<DOC>
<DOCNO> 10405 </DOCNO>
Social organization in the Minority Game model


  We study the role of imitation within the Minority Game model of market. The
players can exchange information locally, which leads to formation of groups
which act as if they were single players. Coherent spatial areas of rich and
poor agents result. We found that the global effectivity is optimized at
certain value of the imitation probability, which decreases with increasing
memory length. The social tensions are suppressed for large imitation
probability, but generally the requirements of high global effectivity and low
social tensions are in conflict.

</DOC>
<DOC>
<DOCNO> 151714 </DOCNO>
Point particle in general background fields and generalized equivalence


  The model of point particle in general external fields is considered and the
generalized equivalence principle is suggested identifying all backgrounds
which give rise to equivalent particle dynamics. The equivalence
transformations for external fields are interpreted as gauge ones. The gauge
group appears to be a semidirect product of all phase space canonical
transformations to an abelian ideal of "hyperWeyl" transformations and includes
U(1) and general coordinate symmetries as a subgroup. The implications of this
gauge symmetry are considered and a connection of general backgrounds to the
infinite collection of Fronsdal gauge fields is studied. Although the result is
negative and no direct connection arises, it is discussed how higher spin
fields could be found among general external fields if one relaxes somehow the
equivalence principle. Besides, the particle action in general backgrounds is
shown to reproduce the De Wit-Freedman point particle -- symmetric tensors
first order interaction suggested many years ago, and generalizes their result
to all orders in interaction.

</DOC>
<DOC>
<DOCNO> 100486 </DOCNO>
3-Manifolds with complexity at most 9


  We describe an algorithm which has enabled us to give a complete list,
without repetitions, of all closed oriented irreducible 3-manifolds of
complexity up to 9. More interestingly, we have actually been able to give a
"name" to each such manifold, by recognizing its canonical decomposition into
Seifert fibred spaces and hyperbolic manifolds.
  The algorithm relies on the extension of Matveev's theory of complexity to
the case of manifolds bounded by suitably marked tori, and on the notion of
assembling of two such manifolds. We show that every manifold is an assembling
of manifolds which cannot be further deassembled, and we prove that there are
surprisingly few such manifolds up to complexity 9.
  Our most interesting experimental discovery is the following: there are 4
hyperbolic manifolds having complexity 9, and they turn out to be precisely the
4 closed hyperbolic manifolds of least known volume. All other manifolds having
complexity at most 9 are graph manifolds.

</DOC>
<DOC>
<DOCNO> 122975 </DOCNO>
Chandra Observations of M31 and their Implications for its ISM


  We have been regularly observing the bulge and inner disk of M31 for nearly 1
year, using both the HRC-I and ACIS-I instruments on the Chandra X-Ray
Observatory. We present results from our program that are of interest to the
study of the ISM in M31. In particular, we find that the unresolved emission
within 3' of the center of M31 has a distinctly softer spectrum than that of
most of the resolved x-ray sources in the region. Preliminary spectral analysis
of bright point sources in the bulge shows no evidence (within the poor
statistics) for soft spectral components, but does reveal significant
extra-galactic x-ray extinction (NH~1E21). We find no new x-ray counterparts to
supernova remnants to date.

</DOC>
<DOC>
<DOCNO> 119133 </DOCNO>
Stochastic Coagulation and the Timescale for Runaway Growth


  We study the stochastic coagulation equation using simplified models and
efficient Monte Carlo simulations. It is known that (i) runaway growth occurs
if the two-body coalescence kernel rises faster than linearly in the mass of
the heavier particle; and (ii) for such kernels, runaway is instantaneous in
the limit that the number of particles tends to infinity at fixed collision
time per particle. Superlinear kernels arise in astrophysical systems where
gravitational focusing is important, such as the coalescence of planetesimals
to form planets or of stars to form supermassive black holes. We find that the
time required for runaway decreases as a power of the logarithm of the the
initial number of particles. Astrophysical implications are briefly discussed.

</DOC>
<DOC>
<DOCNO> 151738 </DOCNO>
On the dimensional reduced theories


  The procedure of the dimensional reduction related to the partition function
of a quantum field living in curved space-time which is the warp product of a
symmetric space is investigated.

</DOC>
<DOC>
<DOCNO> 40250 </DOCNO>
Determination of the CP violating weak phase $\gamma$ from the Decays $B


  We propose a new method to extract the CP violating weak phase $\gamma$ (the
phase of $V_{ub}^*$) in the CKM paradigm of the Standard Model, using $B^-
\rightarrow D^0 \pi^- \rightarrow f \pi^-$ and $B^- \rightarrow \bar D^0 \pi^-
\rightarrow f \pi^-$ decays, where $f$ are final states such as $K^+ \pi^-$,
$K^+ \rho^-$, $K \pi\pi$, {\it etc.} We also study the experimental feasibility
of our new method. With possibility of new phases in the CKM matrix, we
re-examine some of the previously proposed methods to determine $\gamma$, and
find that it would be in principle possible to identify $\gamma$ and a new
phase angle $\theta$ separately.

</DOC>
<DOC>
<DOCNO> 80913 </DOCNO>
QCD Thermodynamics with 2 and 3 Quark Flavors


  We discuss the flavor dependence of the pressure and critical temperature
calculated in QCD with 2, 2+1 and 3 flavors using improved gauge and staggered
fermion actions on lattices with temporal extent Nt=4. For T > 2 Tc we find
that bulk thermodynamics of QCD with 2 light and a heavier strange quark is
well described by 3-flavor QCD while the transition temperature is closer to
that of 2-flavor QCD. Furthermore, we present evidence that the chiral critical
point of 3-flavor QCD, i.e. the second order endpoint of the line of first
order chiral phase transitions, belongs to the universality class of the 3d
Ising model.

</DOC>
<DOC>
<DOCNO> 118385 </DOCNO>
Detection of weak gravitational lensing distortions of distant galaxies


  Most of the matter in the universe is not luminous and can be observed
directly only through its gravitational effect. An emerging technique called
weak gravitational lensing uses background galaxies to reveal the foreground
dark matter distribution on large scales. Light from very distant galaxies
travels to us through many intervening overdensities which gravitationally
distort their apparent shapes. The observed ellipticity pattern of these
distant galaxies thus encodes information about the large-scale structure of
the universe, but attempts to measure this effect have been inconclusive due to
systematic errors. We report the first detection of this ``cosmic shear'' using
145,000 background galaxies to reveal the dark matter distribution on angular
scales up to half a degree in three separate lines of sight. The observed
angular dependence of this effect is consistent with that predicted by two
leading cosmological models, providing new and independent support for these
models.

</DOC>
<DOC>
<DOCNO> 170318 </DOCNO>
Product Bases in Quantum Information Theory


  We review the role of product bases in quantum information theory. We prove
two conjectures which were made in DiVincenzo et al., quant-ph/9908070, namely
the existence of two sets of bipartite unextendible product bases, in arbitrary
dimensions, which are based on a tile construction. We pose some questions
related to complete product bases.

</DOC>
<DOC>
<DOCNO> 12769 </DOCNO>
Synthesis and characterization of the infinite-layer superconductor


  We report the high-pressure synthesis of the electron-doped infinite-layer
superconductor Sr_{0.9}La_{0.1}CuO_{2}. A Rietveld analysis using X-ray powder
diffraction data showed that, within the resolution of the measurement, the
sample was purely an infinite-layer structure without any discernible
impurities. The superconducting volume fraction and the transition width were
greatly improved compared to those in the previous reports. Also the
irreversibility field line was much higher than that of (La,Sr)_{2}CuO_{4}. The
higher value seems to originate from the strong interlayer coupling due to the
reduced average distance between the CuO_{2} planes.

</DOC>
<DOC>
<DOCNO> 120314 </DOCNO>
A comparison of central temperatures of the intracluster gas determined


  A combination of the X-ray imaging and SZ measurements of clusters permits an
indirect determination of the radial temperature profiles of intracluster gas,
which requires no assumption about the dynamical properties and the equation of
state for clusters. A comparison of such a derived gas temperature with that
given by the X-ray spectral analysis constitutes an effective probe of
properties of intracluster gas. Using the available data of 31 clusters in
literature, we have performed the first comparison of the central gas
temperatures provided by the two methods. The good agreement between these two
independent temperature estimates suggests that the distribution of
intracluster gas is essentially consistent with isothermality characterized by
a mean polytropic index of gamma=0.9+-0.1.

</DOC>
<DOC>
<DOCNO> 13421 </DOCNO>
Morphological Symmetry Breaking During Epitaxial Growth at Grazing


  It is shown that, in submonolayer growth at off-normal incidence, even much
less than one percent of transfer from the condensation energy of the deposited
atoms into adatom motion is sufficient to induce a net adatom current from the
illuminated edge of a two-dimensional island to the other edges, thereby
breaking the island symmetry. Such a symmetry breaking phenomenon is most
pronounced for deposition at grazing incidence. Comparison between our
theoretical predictions and existing experimental results confirms the general
validity of the model.

</DOC>
<DOC>
<DOCNO> 100124 </DOCNO>
Log mirror symmetry and local mirror symmetry


  We study Mirror Symmetry of log Calabi-Yau surfaces. On one hand, we consider
the number of ``affine lines'' of each degree in the complement of a smooth
cubic in the projective plane. On the other hand, we consider coefficients of a
certain expansion of a function obtained from the integrals of dxdy/xy over
2-chains whose boundaries lie on B_\phi where {B_\phi} is a family of smooth
cubics. Then, for small degrees, they coincide.
  We discuss the relation between this phenomenon and local mirror symmetry for
projective plane in a Calabi-Yau 3-fold by Chiang-Klemm-Yau-Zaslow.

</DOC>
<DOC>
<DOCNO> 116700 </DOCNO>
Bound states of negatively charged ions induced by a magnetic field


  We analyse the bound states of negatively charged ions which were predicted
to exist because of the presence of a magnetic field by Avron et al. We confirm
that the number of such states is infinite in the approximation of an
infinitely heavy nucleus and provide insight into the underlying physical
picture by means of a combined adiabatic and perturbation theoretical approach.
We also calculate the corresponding binding energies which are qualitatively
different for the states with vanishing and non-vanishing angular momentum. An
outlook on the case of including center of mass effects is presented.

</DOC>
<DOC>
<DOCNO> 116559 </DOCNO>
Metrology and Time


  The algorithm Pi/sinx reveals an elliptic excess which acts as the real
component (Space) inducing the imaginary component (Time). Key words :
metrology, chronogenesis, tropic year, anomalistic year. 
  -----
  L 'algorithme Pi/sinx revele un excedent elliptique constituant la composante
active d ' espace dont la composante reactive exprime la chronogenese tropique
aussi bien qu ' anomalistique.. Mots-cles : metrologie, chronogenese, annee
tropique, annee anomalistique

</DOC>
<DOC>
<DOCNO> 116322 </DOCNO>
"Single-cycle" ionization effects in laser-matter interaction


  We investigate numerically effects related to ``single-cycle'' ionization of
dense matter by an ultra-short laser pulse. The strongly non-adiabatic response
of electrons leads to generation of a megagauss steady magnetic field in
laser-solid interaction. By using two-beam interference, it is possible to
create periodic density structures able to trap light and to generate
relativistic ionization fronts

</DOC>
<DOC>
<DOCNO> 121796 </DOCNO>
A search for L dwarf binary systems


  We present analysis of HST Planetary Camera images of twenty L dwarfs
identified in the course of the Two Micron All-Sky Survey. Four of the targets
have faint, red companions at separations between 0.07 and 0.29 arcseconds (1.6
to 7.6 AU). In three cases, the bolometric magnitudes of the components differ
by less than 0.3 magnitudes. Since the cooling rate for brown dwarfs is a
strong function of mass, similarity in luminosities implies comparable masses.
The faint component in the 2M0850 system, however, is over 1.3 magnitudes
fainter than the primary in the I-band, and ~0.8 magnitudes fainter in M(bol).
Indeed, 2M0850B is ~0.8 magnitudes fainter in I than the lowest luminosity L
dwarf currently known, while the absolute magnitude we deduce at J is almost
identical with M_J for Gl 229B. Theoretical models indicate a mass ratio of
\~0.75. The mean separation of the L dwarf binaries in the current sample is
smaller by a factor of two than amongst M dwarfs. We discuss the implications
of these results for the temperature scale in the L/T transition region and for
the binary frequency amongst L dwarfs.

</DOC>
<DOC>
<DOCNO> 9732 </DOCNO>
Random spread on the family of small-world networks


  We present the analytical and numerical results of a random walk on the
family of small-world graphs. The average access time shows a crossover from
the regular to random behavior with increasing distance from the starting point
of the random walk. We introduce an {\em independent step approximation}, which
enables us to obtain analytic results for the average access time. We observe a
scaling relation for the average access time in the degree of the nodes. The
behavior of average access time as a function of $p$, shows striking similarity
with that of the {\em characteristic length} of the graph. This observation may
have important applications in routing and switching in networks with large
number of nodes.

</DOC>
<DOC>
<DOCNO> 13814 </DOCNO>
Quantum and thermal phase fluctuations in layered superconductors


  I study the effect of quantum and thermal phase fluctuations on the in-plane
and $c$-axis penetration depth of layered d-wave superconductors. First, I show
that quantum phase fluctuations in the superconductor can be damped in the
presence of external screening of Coulomb interactions, and suggest an
experiment to test the importance of these fluctuations, by placing a metal in
close proximity to the superconductor to induce such screening. Second, I show
that a combination of quantum phase fluctuations and the linear temperature
dependence of the in-plane superfluid stiffness leads to a linear temperature
dependence of the c-axis penetration depth, below a temperature scale which is
determined by the magnitude of in-plane dissipation. Such a linear-T behavior
may have been observed in experiments on $BSCCO$ and $YBCO$ materials.

</DOC>
<DOC>
<DOCNO> 101414 </DOCNO>
Cyclic covers of the projective line, their jacobians and endomorphisms


  We study the endomorphism ring $End(J(C))$ of the complex jacobian $J(C)$ of
a curve $y^p=f(x)$ where $p$ is an odd prime and $f(x)$ is a polynomial with
complex coefficiens of degree $n>4$ and without multiple roots. Assume that all
the coefficients of $f$ lie in a (sub)field $K$ and the Galois group of $f$
over $K$ is either the full symmetric group $S_n$ or the alternating group
$A_n$. Then we prove that $End(J(C))$ is the ring of integers in the in the
$p$th cyclotomic field, if $p$ is a Fermat prime (e.g., $p=3,5,17,257$).
  Similar results for $p=2$ (the case of hyperelliptic curves) were obtained by
the author in Math. Res. Lett. 7(2000), 123--132.

</DOC>
<DOC>
<DOCNO> 118081 </DOCNO>
Absorption-Line Probes of Gas and Dust in Galactic Superwinds


  We discuss moderate resolution spectra of the NaD absorption-line in a sample
of 32 far-IR-bright starburst galaxies. In 18 cases, the line is produced
primarily by interstellar gas, and in 12 of these it is blueshifted by over 100
km/s relative to the galaxy systemic velocity. The absorption-line profiles in
these outflow sources span the range from near the galaxy systemic velocity to
a maximum blueshift of 400 to 600 km/s. The outflows occur in galaxies
systematically viewed more nearly face-on than the others. We therefore argue
that the absorbing material consists of ambient interstellar gas accelerated
along the minor axis of the galaxy by a hot starburst-driven superwind. The NaD
lines are optically-thick, but indirect arguments imply total Hydrogen column
densities of N_H = few X 10^{21} cm^{-2}. This implies that the superwind is
expelling matter at a rate comparable to the star-formation rate. This
outflowing material is very dusty: we find a strong correlation between the
depth of the NaD profile and the line-of-sight reddening (E(B-V) = 0.3 to 1
over regions several-to-ten kpc in size). The estimated terminal velocities of
superwinds inferred from these data and extant X-ray data are typically 400 to
800 km/s, are independent of the galaxy rotation speed, and are comparable to
(substantially exceed) the escape velocities for $L_*$ (dwarf) galaxies. The
resulting loss of metals can establish the mass-metallicity relation in
spheroids, produce the observed metallicity in the ICM, and enrich a general
IGM to 10$^{-1}$ solar metallicity. If the outflowing dust grains survive their
journey into the IGM, their effect on observations of cosmologically-distant
objects is significant.

</DOC>
<DOC>
<DOCNO> 11617 </DOCNO>
Local Quasiparticle States around an Anderson Impurity in a d-Wave


  The Kondo effects of an Anderson impurity embedded into a d-wave
superconductor is studied. Within the slave-boson mean-field approach, the
derived Bogoliubov-de Gennes equations are solved via exact diagonalization. We
show that a critical coupling strength, above which the Kondo effect takes
place, exists regardless of whether the band particle-hole symmetry is present
or not. The resonant quasiparticle peaks are found in the local density of
states (LDOS) both directly at the impurity and around its neighbors, which is
in sharp contrast to the case of nonmagnetic unitary impurities, where the LDOS
vanishes on the impurity site.

</DOC>
<DOC>
<DOCNO> 12233 </DOCNO>
Inter- and Intragranular Effects in Superconducting Compacted Platinum


  Compacted platinum powders exhibit a sharp onset of diamagnetic screening at
$T \simeq 1.9$ mK in zero magnetic field in all samples investigated. This
sharp onset is interpreted in terms of the intragranular transition into the
superconducting state. At lower temperatures, the magnetic ac susceptibility
strongly depends on the ac field amplitude and reflects the small intergranular
critical current density $j_{c}$. This critical current density shows a strong
dependence on the packing fraction f of the granular samples. Surprisingly,
$j_{c}$ increases significantly with decreasing f ($j_{c}(B=0, T=0) \simeq
0.07$ A/cm$^{2}$ for f = 0.67 and $j_{c}(B=0, T=0) \simeq 0.8$ A/cm$^{2}$ for f
= 0.50). The temperature dependence of $j_{c}$ shows strong positive curvature
over a wide temperature range for both samples. The phase diagrams of inter-
and intragranular superconductivity for different samples indicate that the
granular structure might play the key role for an understanding of the origin
of superconductivity in the platinum compacts.

</DOC>
<DOC>
<DOCNO> 40264 </DOCNO>
Damping of the HERA effect in DIS?


  The drastic rise of the proton structure function F_2(x,Q^2) when the
Bj\"orken variable x decreases, seen at HERA for a large span of Q^2, negative
values for the 4-momentum transfer, may be damped when Q^2 increases beyond
several hundreds GeV^2. A new data analysis and a comparison with recent models
for the proton structure function is proposed to discuss this phenomenon in
terms of the derivative \partial ln F_2(x,Q^2)/\partial ln(1/x).

</DOC>
<DOC>
<DOCNO> 80676 </DOCNO>
Global obstructions to gauge-invariance in chiral gauge theory on the


  It is shown that certain global obstructions to gauge-invariance in chiral
gauge theory, described in the continuum by Alvarez-Gaume and Ginsparg, are
exactly reproduced on the lattice in the Overlap formulation at small non-zero
lattice spacing (i.e. close to the classical continuum limit). As a
consequence, the continuum anomaly cancellation condition $d_R^{abc}=0$ is seen
to be a necessary (although not necessarily sufficient) condition for anomaly
cancellation on the lattice in the Overlap formulation.

</DOC>
<DOC>
<DOCNO> 9598 </DOCNO>
Photoluminescence Study of Carbon Nanotubes


  ultiwalled carbon nanotubes, prepared by both electric arc discharge and
chemical vapor deposition methods, show a strong visible light emission in
photoluminescence experiments. All the samples employed in the experiments
exhibit nearly same super-linear intensity dependence of the emission bands on
the excitation intensity, and negligible temperature dependence of the central
position and the line shapes of the emission bands. Based upon theoretical
analysis of the electronic band structures and optical transition, it is
suggested that besides the electronic transitions across the fundamental gap,
the transitions between pi and sigma conduction bands are the major source of
the light emissions. A two-step transition mechanism is proposed.

</DOC>
<DOC>
<DOCNO> 174498 </DOCNO>
Discovery of Long-Lived Shape Isomeric States which Decay by Strongly


  The reaction 28Si + 181Ta has been studied at E(Lab) = 125 and 135 MeV.
Coincidences between high energy particles and various X- and gamma-rays from
abnormally long-lived states were observed. e.g. 7.8 - 8.6 MeV alpha-particles
with gamma-rays of a superdeformed band, 5.1 - 5.5 MeV alpha-particles with X-
and gamma-rays of W, Re, and Pt, and 3.88 MeV particles (interpreted as
protons) with 185.8 keV gamma-rays. The data are interpreted in terms of the
production of long-lived (t(1/2) of several months) high spin isomeric states
in the second well of the potential in the parent nuclei, which decay to the
normal states in the daughters, and in the third well of the potential, which
decay to the second well.

</DOC>
<DOC>
<DOCNO> 119989 </DOCNO>
The Harmonic and Sideband Structure of the Kilohertz Quasi-Periodic


  We use data from the Rossi X-ray Timing Explorer to search for harmonics and
sidebands of the two simultaneous kilohertz quasi-periodic oscillations (kHz
QPOs) in Sco X-1. We do not detect any of these harmonics or sidebands, with
95% confidence upper limits to their power between ~ 1% and ~ 10% of the power
of the upper kHz QPO. The oscillations produced at these frequencies may be
attenuated in a scattering corona around the neutron star. We find that upper
limits to the unattenuated power of some of the strongest theoretically
predicted harmonics and sidebands are as low as ~ 2% of the unattenuated power
of the high-frequency QPO in Sco X-1.

</DOC>
<DOC>
<DOCNO> 68236 </DOCNO>
Strange quark polarization of the nucleon: A parameter-independent


  We perform a one-loop calculation of the strange quark polarization ($\Delta
s$) of the nucleon in a SU(3) chiral potential model. We find that if the
intermediate excited quark states are summed over in a proper way, i.e., summed
up to a given energy instead of given radial and orbital quantum numbers,
$\Delta s$ turns out to be almost independent of {\em all} the model
parameters: quark masses, scalar- and vector-potential strengths. The
contribution from the quark-antiquark pair creation and annihilation ``$Z$''
diagrams is found to be significant. Our numerical results agree quite
reasonably with experiments and lattice QCD calculations.

</DOC>
<DOC>
<DOCNO> 152051 </DOCNO>
BFFT formalism applied to the minimal chiral Schwinger model


  The minimal chiral Schwinger model is discussed from the
Batalin-Fradkin-Fradkina-Tyutin point of view. The conversion of second-class
constraints to first-class ones results in an extended gauge-invariant theory
which is equivalent for $a=2$ to the vector Schwinger model at the Lagrangian
level. Here, we present arguments which show that such equivalence does not
exist at the operatorial level.

</DOC>
<DOC>
<DOCNO> 123193 </DOCNO>
Performance of the Light Trigger System in the Liquid Xenon Gamma-Ray


  LXeGRIT is a balloon-borne Compton telescope for MeV gamma-ray astrophysics,
based on a liquid xenon time projection chamber with charge and light readout.
The energy and direction of an incident gamma-ray is reconstructed from the
three-dimensional locations and energy deposits of individual interactions
taking place in the homogeneous detector volume. While the charge signals
provide energy information and X-Y positions, the fast xenon scintillation
light signal is used to trigger the detector. The drift time measurement,
referred to the time of the trigger signal, gives the Z-position with the known
drift velocity. The light is detected by four UV-sensitive photomultiplier
tubes (PMTs). The logical OR of the PMT signals triggers the data acquisition
system with an efficiency which depends on the event energy and location, as
well as on the discriminator thresholds used on the individual PMTs. Results
from experiments with a tagged 22Na source give the spatial distribution of the
light trigger efficiency for 511 keV gamma-rays. When averaged over the whole
sensitive volume amd all PMTs, the trigger efficiency is 47% or 40% for two
discriminator windows used during the LXeGRIT balloon flight of 1999. These
values are strongly affected by the different sensitivity of each PMT. The
corresponding average efficiency at 511 keV for the best of the four PMTs is in
fact 63%, and approaches 100% for interactions taking place in a small volume
right above the PMT.

</DOC>
<DOC>
<DOCNO> 11242 </DOCNO>
Instanton approach to the Langevin motion of a particle in a random


  We develop an instanton approach to the non-equilibrium dynamics in
one-dimensional random environments. The long time behavior is controlled by
rare fluctuations of the disorder potential and, accordingly, by the tail of
the distribution function for the time a particle needs to propagate along the
system (the delay time). The proposed method allows us to find the tail of the
delay time distribution function and delay time moments, providing thus an
exact description of the long-time dynamics. We analyze arbitrary environments
covering different types of glassy dynamics: dynamics in a short-range random
field, creep, and Sinai's motion.

</DOC>
<DOC>
<DOCNO> 102713 </DOCNO>
Geometric quantization of non-relativistic and relativistic Hamiltonian


  We show that non-relativistic and relativistic mechanical systems on a
configuration space Q can be seen as the conservative Dirac constraint systems
with zero Hamiltonians on different subbundles of the same cotangent bundle
T^*Q. The geometric quantization of this cotangent bundle under the vertical
polarization leads to compatible covariant quantizations of non-relativistic
and relativistic Hamiltonian mechanics.

</DOC>
<DOC>
<DOCNO> 102803 </DOCNO>
Extremal properties for dissections of convex 3-polytopes


  A dissection of a convex d-polytope is a partition of the polytope into
d-simplices whose vertices are among the vertices of the polytope.
Triangulations are dissections that have the additional property that the set
of all its simplices forms a simplicial complex. The size of a dissection is
the number of d-simplices it contains. This paper compares triangulations of
maximal size with dissections of maximal size. We also exhibit lower and upper
bounds for the size of dissections of a 3-polytope and analyze extremal size
triangulations for specific non-simplicial polytopes: prisms, antiprisms,
Archimedean solids, and combinatorial d-cubes.

</DOC>
<DOC>
<DOCNO> 67978 </DOCNO>
Regularization and Anomalies in Gauge Theory


  Some of the basic issues related to the regularization and anomalies in gauge
theory are reviewed, with particular emphasis on the recent development in
lattice gauge theory. The generalized Pauli-Villars regularization is discussed
from a view point of the covariant regularization of currents, and the
construction of a regularized effective action in terms of covariant currents
is compared with the lattice formulation of chiral Abelian theory.

</DOC>
<DOC>
<DOCNO> 120984 </DOCNO>
Discovery of a Slow X-Ray Pulsator, AX J1740.1-2847, in the Galactic


  We report the discovery of an X-ray pulsar AX J1740.1-2847 from the Galactic
center region. This source was found as a faint hard X-ray object on 7--8
 September 1998 with the ASCA Galactic center survey observation. Then,
coherent pulsations of P=729 +/- 14 sec period were detected. The
 X-ray spectrum is described by a flat power-law of ~= 0.7 photon index. The
large absorption column of log NH ~= 22.4
 (cm^-2) indicates that AX J1740.1-2847 is a distant source, larger than 2.4
kpc, and possibly near at the Galactic center region. The luminosity in the
2--10 keV band is larger than 2.5 x 10^33 erg/s, or likely to be 3.2 x 10^34
erg/s at the Galactic center distance. Although the slow pulse period does not
discriminate whether AX J1740.1-2847 is a white dwarf or neutron star binary,
the flat power-law and moderate luminosity strongly favor a neutron star
binary.

</DOC>
<DOC>
<DOCNO> 119880 </DOCNO>
Detection limits in space-based transit observations


  From simulations of transit observations, it is found that the detectability
of extrasolar planets depends only on two parameters: The signal-to-noise ratio
during a transit, and the number of data points observed during transits. All
other physical parameters describing transit configurations (planet and star
size, orbital period, orbital half axis, latitude of the transit across star)
can be reduced to these two parameters. In turn, once the dependency between
transit detectability and these two parameters has been determined, predictions
for an instrument's ability to detect transits by any combination of physical
parameters can be derived with ease. These predictions are applied to the
Eddington proposal of a combined Astroseismology/Transit-detection space
mission currently under study by ESA, which is described briefly.

</DOC>
<DOC>
<DOCNO> 8213 </DOCNO>
Renormalization group domains of the scalar Hamiltonian


  Using the local potential approximation of the exact renormalization group
(RG) equation, we show the various domains of values of the parameters of the
O(1)-symmetric scalar Hamiltonian. In three dimensions, in addition to the
usual critical surface $S_{c}$ (attraction domain of the Wilson-Fisher fixed
point), we explicitly show the existence of a first-order phase transition
domain $S_{f}$ separated from $S_{c}$ by the tricritical surface $S_{t}$
(attraction domain of the Gaussian fixed point). $S_{f}$ and $S_{c}$ are two
distinct domains of repulsion for the Gaussian fixed point, but $S_{f}$ is not
the basin of attraction of a fixed point. $S_{f}$ is characterized by an
endless renormalized trajectory lying entirely in the domain of negative values
of the $\phi ^{4}$-coupling. This renormalized trajectory exists also in four
dimensions making the Gaussian fixed point ultra-violet stable (and the
$\phi_{4}^{4}$ renormalized field theory asymptotically free but with a wrong
sign of the perfect action). We also show that very retarded classical-to-Ising
crossover may exist in three dimensions (in fact below four dimensions). This
could be an explanation of the unexpected classical critical behavior observed
in some ionic systems.

</DOC>
<DOC>
<DOCNO> 151506 </DOCNO>
Quantization of fields over de Sitter space by the method of generalized


  A system of generalized coherent states for the de Sitter group obeying the
Klein-Gordon equation and corresponding to the massive spin zero particles over
the de Sitter space is considered. This allows us to construct the quantized
scalar field by the resolution over these coherent states; the corresponding
propagator is computed by the method of analytic continuation to the complex de
Sitter space and coincides with expressions obtained previously by other
methods. Considering the case of spin 1/2 we establish the connection of the
invariant Dirac equation over the de Sitter space with irreducible
representations of the de Sitter group. The set of solutions of this equation
is obtained in the form of the product of two different systems of generalized
coherent states for the de Sitter group. Using these solutions the quantized
Dirac field over de Sitter space is constructed and its propagator is found. It
is a result of action of some de Sitter invariant spinor operator onto the spin
zero propagator with an imaginary shift of a mass. We show that the constructed
propagators possess the de Sitter-invariance and causality properties.

</DOC>
<DOC>
<DOCNO> 71702 </DOCNO>
About the end of the electron spectrum in five-lepton $\mu^+$ decay


  The spectrum of very fast electrons in five-lepton decay $\mu^+\to
e^-e^+e^+\nu\bar\nu,$ that is the main background decay at the study of the
muonium-antimuonium conversion in vacuum, is considered. The essential decrease
of the spectral distribution is demonstrated when the energy of one positron in
this decay is small. Some arguments for such decrease for arbitrary positron
energies are given.

</DOC>
<DOC>
<DOCNO> 119177 </DOCNO>
A self-consistent test of Comptonization models using a long BeppoSAX


  We test accurate models of Comptonization spectra over the high quality data
of the BeppoSAX long look at NGC 5548. The data are well represented by a plane
parallel corona with an inclination angle of 30$^{\circ}$, a soft photon
temperature of 5 eV and a hot plasma temperature and optical depth of $kT_{\rm
e}\simeq$ 360 keV and $\tau\simeq$ 0.1, respectively. If energy balance
applies, such values suggest that a more ``photon-starved'' geometry (e.g. a
hemispheric region) is necessary. The spectral softening detected during a
flare, appears to be associated to a decrease of the heating-to-cooling ratio,
indicating a geometric and/or energetic modification of the disk plus corona
system. The hot plasma temperature derived with the models above is
significantly higher than that obtained fitting the same data with a power law
plus high energy cut off model for the continuum. This is due to the fact that
in anisotropic geometries Comptonization spectra show "intrinsic" curvature
which moves the fitted high energy cut-off to higher energies.

</DOC>
<DOC>
<DOCNO> 8944 </DOCNO>
EXAFS indication of double-well potential for oxygen vibration in


  X-ray absorption spectra of oxide systems Ba_{1-x}K_xBiO_3 and BaPbO_3 above
Bi- and Pb-L3 absorption edges were investigated. It was shown that oxygen ions
move in double-well potential and their oscillations are correlated with charge
carrier movement. Observed breathing-like oxygen vibration in double-well
potential with large amplitude and low frequency causes the strong
electron-phonon coupling and high Tc values in doped BaBiO_3. Based on the
experimental data, the model of relationship of electronic and local crystal
structures is proposed that is in a good agreement with the results of
transport measurements, inelastic neutron and electron scattering, Raman
scattering, and photoemission spectroscopy. In the framework of the model the
possible reasons of superconductivity in perovskite-like oxides are discussed.

</DOC>
<DOC>
<DOCNO> 170159 </DOCNO>
On the Distinguishability of Relativistic Quantum States in Quantum


  Relativistic quantum field theory imposes additional fundamental restrictions
on the distinguishability of quantum states. Because of the unavoidable
delocalization of the quantum field states in the Minkowski space-time, the
reliable (with unit probability) distinguishability of orthogonal states
formally requires infinite time. For the cryptographic protocols which are
finite in time the latter means that the effective ``noise'' is present even in
the ideal communication channel because of the non-localizability of the
quantum field states.

</DOC>
<DOC>
<DOCNO> 8444 </DOCNO>
Bosonic Monocluster Expansion


  We compute connected Green's functions of a Bosonic field theory with cutoffs
by means of a ``minimal'' expansion which in a single move, interpolating a
generalized propagator, performs the usual tasks of the cluster and Mayer
expansion. In this way it allows a direct construction of the infinite volume
or thermodynamic limit and it brings constructive Bosonic expansions closer to
constructive Fermionic expansions and to perturbation theory.

</DOC>
<DOC>
<DOCNO> 7947 </DOCNO>
Coarsening in surface growth models without slope selection


  We study conserved models of crystal growth in one dimension [$\partial_t
z(x,t) =-\partial_x j(x,t)$] which are linearly unstable and develop a mound
structure whose typical size L increases in time ($L = t^n$). If the local
slope ($m =\partial_x z$) increases indefinitely, $n$ depends on the exponent
$\gamma$ characterizing the large $m$ behaviour of the surface current $j$ ($j
= 1/|m|^\gamma$): $n=1/4$ for $1< \gamma <3$ and $n=(1+\gamma)/(1+5\gamma)$ for
$\gamma>3$.

</DOC>
<DOC>
<DOCNO> 13868 </DOCNO>
Continuous families of isospectral Heisenberg spin systems and the


  We investigate classes of quantum Heisenberg spin systems which have
different coupling constants but the same energy spectrum and hence the same
thermodynamical properties. To this end we define various types of
isospectrality and establish conditions for their occurence. The triangle and
the tetrahedron whose vertices are occupied by spins 1/2 are investigated in
some detail. The problem is also of practical interest since isospectrality
presents an obstacle to the experimental determination of the coupling
constants of small interacting spin systems such as magnetic molecules.

</DOC>
<DOC>
<DOCNO> 119630 </DOCNO>
BeppoSAX discovery of a new Seyfert 2 galaxy: 1SAXJ2234.8-2541


  In the present work we report the BeppoSAX serendipitous discovery of the
type 2 AGN 1SAXJ2234.8-2541 in the MECS field of view when pointing at the
Seyfert 2 galaxy NGC7314. The source is optical identified with the bright
(m_B=14.40) galaxy ESO533-G50 at redshift z=0.026. The source is clearly
detected at energies above 4 keV but barely visible below this energy implying
heavy obscuration intrinsic to the source. Spectral analysis indicates a column
density of the order of 2-3 x 10^(23) cm^-2$ and a power law photon index
compatible with values often seen in active galaxies. These X-ray
characteristics suggest a Seyfert 2 classification for 1SAXJ2234.8-2541.
Subsequent spectroscopy of the optical conterpart, ESO533-G50, performed with
the ESO 1.52m telescope at La Silla Observatory, confirms the type 2 nature of
this source and therefore its identification with the X-ray source. We also
report the marginal detection of an iron line centered at 7.29 +/- 0.47 keV and
having an equivalent width of 464 (+636 -398) eV; although marginal, this
result is indicative of the presence of warm material in the source. If instead
the line is associated to cold material, we estimate an upper limit to its
equivalent width of 290 eV. The overall characteristics of 1SAXJ2234.8-2541
strongly suggest that the source is Compton thin.

</DOC>
<DOC>
<DOCNO> 121468 </DOCNO>
An Empirically Based Model for Predicting Infrared Luminosity Functions,


  We predict luminosity functions and number counts for extragalactic infrared
sources at various wavelengths using the framework of our empirically based
model. Comparisons of our galaxy count results with existing data indicate that
either galaxy luminosity evolution is not much stronger than Q=3.1, where L is
proportional to (1+z)^{Q}, or that this evolution does not continue beyond a
redshift of 2. However, a derivation of the far infrared background from
COBE-DIRBE data suggests a stronger evolution for far infrared emission with Q
> 4 in the redshift range beteen 0 and 1. We discuss several interpretations of
these results and also discuss how future observations can reconcile this
apparent conflict. We also make predictions of the redshift distributions of
extragalactic infrared sources at selected flux levels which can be tested by
planned detectors. Finally, we predict the fluxes at which various future
surveys will become confusion limited.

</DOC>
<DOC>
<DOCNO> 117096 </DOCNO>
Shafranov's virial theorem and magnetic plasma confinement


  Shafranov's virial theorem implies that nontrivial magnetohydrodynamical
equilibrium configurations must be supported by externally supplied currents.
Here we extend the virial theorem to field theory, where it relates to
Derrick's scaling argument on soliton stability. We then employ virial
arguments to investigate a realistic field theory model of a two-component
plasma, and conclude that stable localized solitons can exist in the bulk of a
finite density plasma. These solitons entail a nontrivial electric field which
implies that purely magnetohydrodynamical arguments are insufficient for
describing stable, nontrivial structures within the bulk of a plasma.

</DOC>
<DOC>
<DOCNO> 83148 </DOCNO>
A Problem-Specific Fault-Tolerance Mechanism for Asynchronous,


  The idle computers on a local area, campus area, or even wide area network
represent a significant computational resource---one that is, however, also
unreliable, heterogeneous, and opportunistic. This type of resource has been
used effectively for embarrassingly parallel problems but not for more tightly
coupled problems. We describe an algorithm that allows branch-and-bound
problems to be solved in such environments. In designing this algorithm, we
faced two challenges: (1) scalability, to effectively exploit the variably
sized pools of resources available, and (2) fault tolerance, to ensure the
reliability of services. We achieve scalability through a fully decentralized
algorithm, by using a membership protocol for managing dynamically available
resources. However, this fully decentralized design makes achieving reliability
even more challenging. We guarantee fault tolerance in the sense that the loss
of up to all but one resource will not affect the quality of the solution. For
propagating information efficiently, we use epidemic communication for both the
membership protocol and the fault-tolerance mechanism. We have developed a
simulation framework that allows us to evaluate design alternatives. Results
obtained in this framework suggest that our techniques can execute scalably and
reliably.

</DOC>
<DOC>
<DOCNO> 69064 </DOCNO>
Yukawa Unified Supersymmetric SO(10) Model: Cosmology, Rare Decays and


  It has recently been pointed out that viable sparticle mass spectra can be
generated in Yukawa unified SO(10) supersymmetric grand unified models
consistent with radiative breaking of electroweak symmetry. Model solutions are
obtained only if $\tan\beta \sim 50$, $\mu <0$ and positive $D$-term
contributions to scalar masses from SO(10) gauge symmetry breaking are used. In
this paper, we attempt to systematize the parameter space regions where
solutions are obtained. We go on to calculate the relic density of neutralinos
as a function of parameter space. No regions of the parameter space explored
were actually cosmologically excluded, and very reasonable relic densities were
found in much of parameter space. Direct neutralino detection rates could
exceed 1 event/kg/day for a $^{73}$Ge detector, for low values of GUT scale
gaugino mass $m_{1/2}$. We also calculate the branching fraction for $b\to s
\gamma$ decays, and find that it is beyond the 95% CL experimental limits in
much, but not all, of the parameter space regions explored. However, recent
claims have been made that NLO effects can reverse the signs of certain
amplitudes in the $b\to s\gamma$ calculation, leading to agreement between
theory and experiment in Yukawa unified SUSY models. For the Fermilab Tevatron
collider, significant regions of parameter space can be explored via
$b\bar{b}A$ and $b\bar{b}H$ searches. There also exist some limited regions of
parameter space where a trilepton signal can be seen at TeV33. Finally, there
exist significant regions of parameter space where direct detection of bottom
squark pair production can be made, especially for large negative values of the
GUT parameter $A_0$.

</DOC>
<DOC>
<DOCNO> 70464 </DOCNO>
Grand Unification Signal from Ultra High Energy Cosmic Rays?


  The spectrum of ultrahigh energy (above \approx 10^{9} GeV) cosmic rays is
consistent with the decay of GUT scale particles. The predicted mass is
m_X=10^b GeV, where b=14.6_{-1.7}^{+1.6}.

</DOC>
<DOC>
<DOCNO> 99951 </DOCNO>
The canonical transformations of the dynamical multiparameter systems as


  The theory of recurrence relations of linear multi-component and
multi-parameter systems on the basis of the canonical transformations theory of
the dynamical systems' sets is constructed. The parameters of the grating's
knots are defined from the condition of the invariance of the model under
shifts along the grating. The connection with a zero curvature representation
for models on the grating is installed. The examples of two- and
three-parameter systems described by the hypergeometric functions
M(\alpha,\beta,t) and M(\alpha,\beta,\xi,t) are considered in details. The
canonical recurrence relations increasing and decreasing parameters
{\alpha,\beta,\xi} for solutions of the corresponding equations are
constructed.

</DOC>
<DOC>
<DOCNO> 178821 </DOCNO>
Strong and electromagnetic interaction views on deuteron structure


  The purpose of this contribution is to give an outlook of recent results
connected with deuteron physics, with electromagnetic and strong interacting
probes at intermediate energy. Special attention will be devoted to
polarization observables.

</DOC>
<DOC>
<DOCNO> 102543 </DOCNO>
New Proof of the Cobordism Invariance of the Index


  We give a simple proof of the cobordism invariance of the index of an
elliptic operator. The proof is based on a study of a Witten-type deformation
of an extension of the operator to a complete Riemannian manifold. One of the
advantages of our approach is that it allows to treat directly general elliptic
operator which are not of Dirac type.

</DOC>
<DOC>
<DOCNO> 85541 </DOCNO>
Mass neutrino flavor evolution in spacetime with torsion


  In the framework of the spacetime with torsion, we obtain the flavor
evolution equation of the mass neutrino oscillation in vacuum. A comparison
with the result of general relativity case, it shows that the flavor
evolutionary equations in Riemann spacetime and Weitzenb\"ock spacetimes are
equivalent in the spherical symmetric Schwarzschild spacetime, but turns out to
be different in the case of the axial symmetry.

</DOC>
<DOC>
<DOCNO> 102429 </DOCNO>
A note on strong geometric isolation in 3-orbifolds


  Neumann and Reid described in their paper "Rigidity of cusps in deformations
of hyperbolic 3-orbifolds" (Math Ann. 295 (1993) no. 2, 223--237) a 2-cusped
hyperbolic 3-orbifold in which the cusps are geometrically isolated. Based on
numerical evidence provided by Jeff Weeks' snappea program, they conjectured
that the cusps are strongly geometrically isolated, a fact which we establish
here. We also give a parameterization of the Dehn surgery space of this
orbifold which has amusing properties.

</DOC>
<DOC>
<DOCNO> 118518 </DOCNO>
Fundamental properties of the open cluster NGC 2355


  NGC 2355 is an old open cluster in the outer part of the galactic disk (l=203
deg, b=+11 deg) which has been little studied until now. This paper presents
the first astrometric and spectroscopic investigation of this cluster. We have
measured precise absolute proper motions from old Carte du Ciel plates, POSS-I
plates and recent CCD observations obtained with the Bordeaux meridian circle.
The proper motion data reveal 38 highly probable cluster members down to B=15
mag within 7' of the cluster center. We have also obtained ELODIE high
resolution spectra for 24 stars. Seventeen of them are confirmed to be members
of the cluster on the basis of radial velocity. Eight of them are fast rotating
turnoff stars for which the projected rotational velocity has been determined.
The spectroscopic observations have also provided estimates of the physical
parameters Teff, log(g), [Fe/H], Mv of the 24 target stars. Two stragglers have
been identified in the cluster. Combining our astrometric and spectroscopic
results with previous UBV photometry and recent JHKs photometry from the 2MASS
survey we have derived the fundamental properties of the cluster : metallicity,
age, distance, size, spatial velocity and orbit.

</DOC>
<DOC>
<DOCNO> 13335 </DOCNO>
Ab Initio Treatments of the Ising Model in a Transverse Field


  In this article, new results are presented for the zero-temperature
ground-state properties of the spin-half transverse Ising model on various
lattices using three different approximate techniques. These are, respectively,
the coupled cluster method, the correlated basis function method, and the
variational quantum Monte Carlo method. The methods, at different levels of
approximation, are used to study the ground-state properties of these systems,
and the results are found to be in excellent agreement both with each other and
with results of exact calculations for the linear chain and results of exact
cumulant series expansions for lattices of higher spatial dimension. The
different techniques used are compared and contrasted in the light of these
results, and the constructions of the approximate ground-state wave functions
are especially discussed.

</DOC>
<DOC>
<DOCNO> 12937 </DOCNO>
Rapidly Quenched Kosterlitz-Thouless Superfluid Transitions


  Rapidly quenched Kosterlitz-Thouless (KT) superfluid transitions are studied
by solving the Fokker-Planck equation for the vortex-pair dynamics in
conjunction with the KT recursion relations. Power-law decays of the vortex
density at long times are found, and the results are in agreement with a
scaling proposal made by Minnhagen and co-workers for the dynamical critical
exponent. The superfluid density is strongly depressed after a quench, with the
subsequent recovery being logarithmically slow for starting temperatures near
T$_{KT}$. No evidence is found of vortices being ''created'' in a rapid quench,
there is only decay of the existing thermal vortex pairs.

</DOC>
<DOC>
<DOCNO> 69793 </DOCNO>
Self-gravitating bosons at nonzero temperature


  A system of charged bosons at finite temperature and chemical potential is
studied in a general-relativistic framework. We assume that the boson fields
interact only gravitationally. At sufficiently low temperature the system
exists in two phases: the gas and the condensate. By studying the condensation
process numerically we determine the critical temperature $T_c$ at which the
condensate emerges. As the temperature decreases, the system eventually settles
down in the ground state of a cold boson star.

</DOC>
<DOC>
<DOCNO> 80610 </DOCNO>
One-loop renormalization of fermionic currents with the overlap-Dirac


  We compute the one-loop lattice renormalization of the two-quark operators
$\bar{\psi} \Gamma \psi$, where $\Gamma$ denotes the generic Dirac matrix, for
the lattice formulation of QCD using the overlap-Dirac operator.
  We also study the renormalization of quark bilinears which are more extended
and have better chiral properties.
  Finally, we present improved estimates of these renormalization constants,
coming from cactus resummation and from mean field perturbation theory.

</DOC>
<DOC>
<DOCNO> 117392 </DOCNO>
On the peculiar red clump morphology in the open clusters NGC 752 and


  The red clump stars in the open cluster NGC 752 present a peculiar
distribution in the colour-magnitude diagran (CMD): the clump is observed to
present a faint extension, slightly to the blue of the main concentration of
clump stars. We point out that a similar structure is present in the CMD of NGC
7789, and discuss their possible origins. This feature may be understood as the
result of having, at the same time, stars of low-mass which undergo the
helium-flash, and those just massive enough for avoiding it. The ages of both
clusters are compatible with this interpretation. Similar features can be
produced in theoretical models which assume a non-negligible mass spread for
clump stars, of about 0.2 Mo. However, one can probably exclude that the
observed effect is due to the natural mass range of core helium burning stars
found in single isochrones, although present models do not present the level of
detail necessary to completely explore this possibility. Also the possibility
of a large age spread among cluster stars can be refuted on observational
grounds. We then suggest a few alternatives. This spread may be resulting
either from star-to-star variations in the mass-loss rates during the RGB
phase. Alternatively, effects sush as stellar rotation or convective core
overshooting, could be causing a significant spread in the core mass at
He-ignition for star of similar mass. Finally, we point out that similar
effects could also help to understand the distribution of clump stars in the
CMDs of the clusters NGC 2660 and NGC 2204.

</DOC>
<DOC>
<DOCNO> 8683 </DOCNO>
Two dimensional anisotropic non Fermi-liquid phase of coupled Luttinger


  We show using bosonization techniques, that strong forward scattering
interactions between one dimensional spinless Luttinger liquids (LL) can
stabilize a phase where charge-density wave, superconducting and transverse
single particle hopping perturbations are irrelevant. This new phase retains
its LL like properties in the directions of the chains, but with relations
between exponents modified by the transverse interactions, whereas, it is a
perfect insulator in the transverse direction. The mechanism that stabilizes
this phase are strong transverse charge density wave fluctuations at
incommensurate wavevector, which frustrates crystal formation by preventing
lock-in of the in-chain density waves.

</DOC>
<DOC>
<DOCNO> 40448 </DOCNO>
Possible Observation of a Second Kind of Light


  According to classical electrodynamics, sunlight that is passed through an
iron layer can be detected with the naked eye only if the thickness of the
layer is less than 170nm. However, in an old experiment, August Kundt was able
to see the sunlight with the naked eye even when it had passed an iron layer
with thickness greater than 200nm. To explain this observation, we propose a
second kind of light which was introduced in a different context by Abdus
Salam. A tabletop experiment can verify this possibility.

</DOC>
<DOC>
<DOCNO> 121733 </DOCNO>
Blank field submm sources, failed stars, and the dark matter


  I discuss the possibility that a significant fraction (possibly a third) of
the faint SCUBA sources are not in fact high redshift galaxies, but actually
local cold dark dusty gas clouds emitting only in the submm, with a temperature
around 7K. I show that the observational constraints on such a population -
dynamical limits on missing matter, the FIR-mm background, and the absence of
gross high-latitude extinction features - constrains the mass of such objects
to be in the range 0.1 - 10 Jupiter masses. The characteristics deduced are
closely similar to those of the objects proposed by Walker and Wardle (1998) to
explain halo dark matter. However, such objects, if they explain a large
fraction of the SCUBA sources, cannot extend through the halo without greatly
exceeding the FIR-mm background. Instead, I deduce the characteristic distance
of the SCUBA sources to be around 100 pc, consistent with being drawn from a
disk population with a scale height of few hundred parsecs. Regardless of the
dark matter problem, the possible existence of such compact sub-stellar but
non-degenerate objects is intriguing. They may be seen as "failed stars",
representing an alternative end-point to brown dwarfs. It is possible that they
greatly outnumber both stars and brown dwarfs. The nearest such object could be
a fraction of a parsec away. Several relatively simple observations could
critically test this hypothesis.

</DOC>
<DOC>
<DOCNO> 102813 </DOCNO>
Hyperelliptic curves in characteristic 2


  In this paper we prove that there are no hyperelliptic supersingular curves
over F_2bar of genus 2^n-1 for any integer n>1. Let g be a natural number, and
h=floor(log_2(g+1)+1). Let X be a hyperelliptic curve over F_2bar of genus g>2
and 2-rank zero, given by an affine equation y^2-y=c_{2g+1} x^{2g+1} +...+ c_1
x. We prove that the first slope of the Newton polygon of X is bigger than or
equal to 1/h. We also prove that the equality holds if (I) g<2^h-2, c_{2^h-1}
is nonzero; or (II) g=2^h-2, c_{2^h-1} or c_{3(2^{h-1})-1} is nonzero. We prove
that genus-4 hyperelliptic curve over F_2bar are precisely those with equations
y^2 - y = x^9 + a x^5 + b x^3.

</DOC>
<DOC>
<DOCNO> 119633 </DOCNO>
Detection of interstellar CH_3


  Observations with the Short Wavelength Spectrometer (SWS) onboard the {\it
Infrared Space Observatory} (ISO) have led to the first detection of the methyl
radical ${\rm CH_3}$ in the interstellar medium. The $\nu_2$ $Q-$branch at 16.5
$\mu$m and the $R$(0) line at 16.0 $\mu$m have been unambiguously detected
toward the Galactic center SgrA$^*$. The analysis of the measured bands gives a
column density of (8.0$\pm$2.4)$\times10^{14}$ cm$^{-2}$ and an excitation
temperature of $(17\pm 2)$ K. Gaseous ${\rm CO}$ at a similarly low excitation
temperature and ${\rm C_2H_2}$ are detected for the same line of sight. Using
constraints on the ${\rm H_2}$ column density obtained from ${\rm C^{18}O}$ and
visual extinction, the inferred ${\rm CH_3}$ abundance is
$(1.3{{+2.2}\atop{-0.7}}) \times 10^{-8}$. The chemically related ${\rm CH_4}$
molecule is not detected, but the pure rotational lines of ${\rm CH}$ are seen
with the Long Wavelength Spectrometer (LWS). The absolute abundances and the
${\rm CH_3/CH_4}$ and ${\rm CH_3/CH}$ ratios are inconsistent with published
pure gas-phase models of dense clouds. The data require a mix of diffuse and
translucent clouds with different densities and extinctions, and/or the
development of translucent models in which gas-grain chemistry, freeze-out and
reactions of ${\rm H}$ with polycyclic aromatic hydrocarbons and solid
aliphatic material are included.

</DOC>
<DOC>
<DOCNO> 70026 </DOCNO>
Signals of the degenerate BESS model at the LHC


  We discuss the possible signals of the degenerate BESS model at the LHC. This
model describes a strongly interacting scenario responsible of the spontaneous
breaking of the electroweak symmetry. It predicts two triplets of extra gauge
bosons which are almost degenerate in mass. Due to this feature, the model has
the property of decoupling and therefore, at low energies (below or of the
order of $100 GeV$) it is nearly indistinguishable from the Standard Model.
However the new resonances, both neutral and charged, should give quite
spectacular signals at the LHC, where the c.o.m. energy will allow to produce
these gauge bosons directly.

</DOC>
<DOC>
<DOCNO> 9836 </DOCNO>
Similarity transformation in one-dimensional reaction-diffusion systems;


  The exact solution for a system with two-particle annihilation and
decoagulation has been studied. The spectrum of the Hamiltonian of the system
is found. It is shown that the steady state is two-fold degenerate. The average
number density in each cite <n_i(t)> and the equal time two-point functions
<n_i(t), n_j(t)> are calculated. Any equal time correlation functions at large
times,
  $<n_i({\infty}), n_j({\infty}), ...>$, is also calculated. The relaxation
behaviour of the system toward its final state is investigated and it is shown
that generally it is exponential, as it is expected. For the special symmetric
case, the relaxation behaviour of the system is a power law. For the asymmetric
case, it is shown that the profile of deviation from the final values is an
exponential function of the position.

</DOC>
<DOC>
<DOCNO> 101981 </DOCNO>
Singularities and the wave equation on conic spaces


  Let $X$ be a manifold with boundary, endowed with a metric with conic
singularities at the boundary components of $X$. Let $u$ be a solution to the
wave equation on $\mathbb{R} \times X$. When a singularity of $u$ strikes a
cone point of $X$, it undergoes a mixture of diffractive spreading and
geometric propagation.

</DOC>
<DOC>
<DOCNO> 13756 </DOCNO>
Recent Progress in the Computational Many-Body Theory of Metal Surfaces


  In this article we describe recent progress in the computational many-body
theory of metal surfaces, and focus on current techniques beyond the
local-density approximation of density-functional theory. We overview various
applications to ground and excited states. We discuss the exchange-correlation
hole, the surface energy, and the work function of jellium surfaces, as
obtained within the random-phase approximation, a time-dependent
density-functional approach, and quantum Monte Carlo methods. We also present a
survey of recent quasiparticle calculations of unoccupied states at both
jellium and real surfaces.

</DOC>
<DOC>
<DOCNO> 121103 </DOCNO>
Kinematics of the Parsec-Scale Relativistic Jet in Quasar 3C 279: 1991 -


  We present results of long-term high-frequency VLBI monitoring of the
relativistic jet in 3C279, consisting of 18 epochs at 22 GHz from 1991 to 1997
and 10 epochs at 43 GHz from 1995 to 1997. Three major results of this study
are: apparent speeds measured for six superluminal components range from 4.8 to
7.5 c (H_{0}=70 km s^{-1} Mpc^{-1}, q_{0}=0.1), variations in the total radio
flux are due primarily to changes in the VLBI core flux, and the uniform-sphere
brightness temperature of the VLBI core is about 1 x 10^{13} K at 22 GHz after
1995, one of the highest direct estimates of a brightness temperature. If the
variability brightness temperature measured for 3C279 by Lahteenmaki & Valtaoja
is an actual value and not a lower limit, then the rest-frame brightness
temperature of 3C279 is quite high and limited by inverse Compton effects
rather than equipartition. The parsec-scale morphology of 3C279 consists of a
bright, compact VLBI core, a jet component (C4) that moved from about 2 mas to
about 3.5 mas from the core during the course of our monitoring, and an inner
jet that extends from the core to a stationary component, C5, at about 1 mas
from the core. Components in the inner jet are relatively short-lived, and fade
by the time they reach about 1 mas from the core. The components have different
speeds and position angles from each other, but these differences do not match
the differences predicted by the precession model of Abraham & Carrara.
Although VLBI components were born about six months prior to each of the two
observed gamma-ray high states, the sparseness of the gamma-ray data prevents a
statistical analysis of possible correlations.

</DOC>
<DOC>
<DOCNO> 40421 </DOCNO>
Precision measurements of the Lambda_c+ and D0 lifetimes


  We report new precision measurements of the lifetimes of the Lambda_c+ and D0
from SELEX, the charm hadro-production experiment at Fermilab. Based upon 1630
Lambda_c+ and 10210 D0 decays we observe lifetimes of tau[Lambda_c+] = 198.1 +-
7.0 +- 5.6 fs and tau[D0] = 407.9 +- 6.0 +- 4.3 fs

</DOC>
<DOC>
<DOCNO> 120977 </DOCNO>
HST Optical-NIR Colors of Nearby $R^{1/4}$ and Exponential Bulges


  We have analysed $V$, $H$ and $J$ HST images for a sample of early- to
late-type spiral galaxies, and reported elsewhere the statistical frequency of
$R^{1/4}$-law and exponential bulges in our sample as a function of Hubble
type, and the frequency of occurrence and structural properties of the resolved
central nuclei hosted by intermediate- to late-type bulges and disks (see
references in the text). Here we use these data to show that: {\it (i)} The
$V-H$ color distribution of the $R^{1/4}$ bulges peaks around $<V-H> \sim 1.3$,
with a sigma $\Delta (V-H) \sim 0.1$ magnitudes. Assuming a solar metallicity,
these values correspond to stellar ages of $\approx 6 \pm 3$ Gyrs. In contrast,
the $V-H$ color distribution of the exponential bulges peaks at $<V-H> \sim
0.9$ and has a sigma $\Delta (V-H) \sim 0.4$ mags. This likely implies
significantly smaller ages and/or lower metallicities for (a significant
fraction of the stars in) the exponential bulges compared to the $R^{1/4}$-law
spheroids. {\it (ii)} Most of the central nuclei hosted by the exponential
bulges have $V-H$ and $J-H$ colors which are compatible with relatively
unobscured stellar populations. Assuming no or little dust effects, ages $\gta
1$ Gyrs are suggested for these nuclei, which in turn imply masses of about a
few 10$^6$ to a few 10$^7$ M$_\odot$, i.e., sufficient to dissolve progenitor
bars with masses consistent with those inferred for the exponential bulges by
their luminosities. {\it (iii)} While different bulge-nucleus pairs cover a
large range of $V-H$ colors, each bulge-nucleus pair has quite similar $V-H$
colors, and thus possibly similar stellar populations. (abridged)

</DOC>
<DOC>
<DOCNO> 12570 </DOCNO>
Enhanced Bound State Formation in Two Dimensions via Stripe-Like Hopping


  We have investigated two-electron bound state formation in a square
two-dimensional t-J-U model with hopping anisotropies for zero electron
density; these anisotropies are introduced to mimic the hopping energies
similar to those expected in stripe-like arrangements of holes and spins found
in various transition metal oxides. In this report we provide analytical
solutions to this problem, and thus demonstrate that bound-state formation
occurs at a critical exchange coupling, J_c, that decreases to zero in the
limit of extreme hopping anisotropy t_y/t_x -> 0. This result should be
contrasted with J_c/t = 2 for either a one-dimensional chain, or a
two-dimensional plane with isotropic hopping. Most importantly, this behaviour
is found to be qualitatively similar to that of two electrons on the two-leg
ladder problem in the limit of t_interchain/t_intrachain -> 0. Using the latter
result as guidance, we have evaluated the pair correlation function, thus
determining that the bound state corresponds to one electron moving along one
chain, with the second electron moving along the opposite chain, similar to two
electrons confined to move along parallel, neighbouring, metallic stripes. We
emphasize that the above results are not restricted to the zero density limit -
we have completed an exact diagonalization study of two holes in a 12 X 2
two-leg ladder described by the t-J model and have found that the
above-mentioned lowering of the binding energy with hopping anisotropy persists
near half filling.

</DOC>
<DOC>
<DOCNO> 122946 </DOCNO>
A radio and optical study of Molonglo radio sources


  We present multi-wavelength radio observations with the Very Large Array and
narrow- and broad-band optical observations with the 2.5m telescope at the Las
Campanas Observatory, of a well-defined sample of high-luminosity
Fanaroff-Riley class II radio galaxies and quasars, selected from the Molonglo
Reference Catalogue 1-Jy sample. These observations were carried out as part of
a programme to investigate the effects of orientation and environment on some
of the observed properties of these sources. We examine the dependence of the
Liu-Pooley relationship, which shows that radio lobes with flatter radio
spectra are less depolarized, on size, identification and redshift, and show
that it is significantly stronger for smaller sources, with the strength of the
relationship being similar for both radio galaxies and quasars. In addition to
Doppler effects, there appears to be intrinsic differences between the lobes on
opposite sides. We discuss the asymmetry in brightness and location of the
hotspots, and present estimates of the ages and velocities from matched
resolution observations at L- and C-bands. The narrow- and broad-band optical
images of some of these sources were made to study their environments and
correlate with the symmetry parameters. Extended emission-line region is seen
in a quasar and in four of the objects, possible companion galaxies are seen
close to the radio axis.

</DOC>
<DOC>
<DOCNO> 118528 </DOCNO>
Two Large HI Shells in the Outer Galaxy near l=279 degrees


  As part of a survey of HI 21-cm emission in the Southern Milky Way, we have
detected two large shells in the interstellar neutral hydrogen near l=279 deg.
The center velocities are +36 and +59 km/s, which puts the shells at kinematic
distances of 7 and 10 kpc. The larger shell is about 610 pc in diameter and
very empty, with density contrast of at least 15 between the middle and the
shell walls. It has expansion velocity of about 20 km/s and swept up mass of
several million solar masses. The energy indicated by the expansion may be as
high as 2.4 X 10^53 ergs. We estimate its age to be 15 to 20 million years. The
smaller shell has diameter of about 400 pc, expansion velocity about 10 km/s
and swept up mass of about 10^6 solar masses.
  Morphologically both regions appear to be shells, with high density regions
mostly surrounding the voids, although the first appears to have channels of
low density which connect with the halo above and below the HI layer. They lie
on the edge of the Carina arm, which suggests that they may be expanding
horizontally into the interarm region as well as vertically out of the disk. If
this interpretation is correct, this is the first detection of an HI chimney
which has blown out of both sides of the disk.

</DOC>
<DOC>
<DOCNO> 116337 </DOCNO>
Remote Sensing of Geomagnetic Field and Applications to Climate


  Observations show that geomagnetic field lines follow closely the atmospheric
circulation patterns and that geomagnetic field variations are precursors to
climate change . The exact mechanism for the observed close relationship
between global geomagnetic field and the tropospheric weather patterns is not
clear. In this paper a universal theory of atmospheric eddy dynamics is
presented which shows that the global geomagnetic field, atmospheric electric
field and weather systems are manifestations of a semi permanent scale
invariant hierarchical atmospheric eddy continuum. Quantitative equations are
derived to show that the full continuum of atmospheric eddies exist as a
unified whole and originate from buoyant energy supply from frictional
turbulence at the planetary surface . Large eddy growth occurs from turbulence
scale by the universal period doubling route to chaos . The turbulent eddies
are carried upwards on the large eddy envelopes and vertical mixing occurs by
the turbulent eddy fluctuations resulting in downward transport of negative
space charges from higher levels and simultaneous upward transport of positive
space charges from surface levels. The eddy circulations therefore generate a
large-scale vertical aerosol current, which is of the correct sign and
magnitude to generate the horizontal component of the geomagnetic field.
Therefore, atmospheric circulation patterns leave signature on the geomagnetic
field lines whose global variations can be easily monitored by satellite borne
sensors and thus assist in weather and climate prediction.

</DOC>
<DOC>
<DOCNO> 67929 </DOCNO>
Enhanced Structure Function Of The Nucleon From Deep Inelastic


  The proton structure function is re-deduced from the data of deep inelastic
electron-proton scattering after enhanced correction that is made due to the
multiple scattering effect. The Glauber approach is used to account for the
multiple scattering of electron with the quark constituents of the proton. The
results are compared with the prediction of the parton model. Appreciable
deviation is observed only at low values of the Bjorken scaling, which
correspond to the extremely deep inelastic scattering.

</DOC>
<DOC>
<DOCNO> 100077 </DOCNO>
Special Lagrangian submanifolds and Algebraic complexity one Torus


  In the first part of this paper we consider compact algebraic manifolds M^2n
with an algebraic (n-1)-Torus action. We show that there is a T-invariant
meromorphic section $\sigma$ of the canonical bundle of M. Any such $\sigma$
defines a divisor D. On the complement M'=M-D we have a trivialization of the
canonical bundle and a T-action. If the first cohomology of M' vanishes, then
results of [2] imply that there is a Special Lagrangian (SLag) fibration on M'.
We study how the fibers compactify in M and give examples of SLag fibrations on
M', including some cases there the first cohomology of M' doesn't vanish.
  In the second part of the paper we study Calabi-Yau hypersurfaces in M. We
assume that $\sigma$ is an inverse of a holomorphic section $\eta$ of the
anti-canonical bundle of M. We will see that under certain assumptions one can
choose a holomorphic volume form on the smooth part D' of the divisor D s.t.
orbits of the T-action give a SLag fibration on D' with respect to the metric,
induced from M. Transversal sections $\eta_j$ near $\eta$ define smooth
Calabi-Yau hypersurfaces D_j in M. We will show that one can deform the SLag
fibration on D' to SLag fibrations on large parts of D_j. This construction
applies for instance for D_j being quintics in CP^4 or Calabi-Yau hypersurfaces
in the Grassmanian G(2,4).

</DOC>
<DOC>
<DOCNO> 10924 </DOCNO>
Stochastic Stability


  In this talk I will introduce the principle of stochastic stability and
discussing its consequences both at equilibrium and off-equilibrium.

</DOC>
<DOC>
<DOCNO> 169934 </DOCNO>
Teleportation Criteria: Form and Significance


  Our criteria for continuous variable quantum teleportation [T.C.Ralph and
P.K.Lam, Phys.Rev.Lett. {\bf 81}, 5668 (1998)] take the form of sums, rather
than products, of conjugate quadrature measurements of the signal transfer
coefficients and the covariances between the input and output states. We
discuss why they have this form. We also discuss the physical significance of
the covariance inequality.

</DOC>
<DOC>
<DOCNO> 71448 </DOCNO>
Spin-Dependent WIMPs in DAMA?


  We investigate whether the annual modulation observed in the DAMA experiment
can be due to a weakly-interacting massive particle (WIMP) with an axial-vector
(spin-dependent; SD) coupling to nuclei. We evaluate the SD WIMP-proton cross
section under the assumption that such scattering accounts for the DAMA
modulation, and we do the same for a SD WIMP-neutron cross section. We show
that SD WIMP-proton scattering is ruled out in a model-independent fashion by
null searches for energetic neutrinos from WIMP annihilation in the Sun, and
that SD WIMP-neutron scattering is ruled out for WIMP masses > 20 GeV by the
null result with the DAMA Xe detector. A SD WIMP with mass < 20 GeV is still
compatible, but only if the SD WIMP-neutron interaction is four orders of
magnitude greater than the WIMP-proton interaction.

</DOC>
<DOC>
<DOCNO> 69227 </DOCNO>
What we know about the Theoretical Foundation of Duality in Electron


  We consider some of the things that we understand about the theoretical
underpinnings of duality, including items such as why the resonance
peak/background ratio is constant in general, why it falls for the
$\Delta(1232)$, what we might expect for scaling and duality with longitudinal
or spin-dependent structure functions, and what kind of scaling or duality we
might expect for semiexclusive processes.

</DOC>
<DOC>
<DOCNO> 67669 </DOCNO>
A proposal on the search for the hybrid with $I^G(J^{PC})=1^-(1^{-+})$


  The moment expressions for the boson resonances X with spin-parity 0++, 1-+,
1++, and 2++ possibly produced in the process $J/\psi\to\rho X$, $X\to
b_1(1235)\pi$, $b_1\to \omega \pi$ are given in terms of the generalized moment
analysis method. The 1-+ resonance can be distinguished from other resonances
by means of these moments except for some rather special cases. The suggestion
that the search for the 1-+ hybrid can be performed in the above decay channel
at upgraded BEPC/BES is presented.

</DOC>
<DOC>
<DOCNO> 121512 </DOCNO>
Secondary CMB anisotropies from the kinetic SZ effect


  We present an analytic model, based on previous works which tackled the
reionization history of the universe, which allows us to describe the
generation of the secondary CMB anisotropies due to the kinetic SZ effect. We
take into account the "patchy pattern" of reionization (HII bubbles), the
cross-correlations of these ionized regions, the small-scale fluctuations of
the matter density field and the contribution from collapsed objects. For an
open universe, we find that the power-spectrum $l(l+1)C_l/(2\pi)$ exhibits a
plateau of height $10^{-13}$ in the range $10^3 < l < 10^6$. We find that for
large wavenumbers $l > 10^4$ the signal is dominated by the contribution from
collapsed halos while for $l < 10^4$ it is governed by the large-scale
correlations of HII bubbles. This implies that one cannot discriminate
reionization by stars from a quasar-driven scenario since the size of ionized
regions never dominates the behaviour of the anisotropies. Moreover, the
secondary CMB anisotropies arise from a broad range of redshifts (7.5<z<10 for
the IGM and 0<z<7 for galactic halos). The signal expected in our model might
bias the cosmological parameter estimation from CMB experiments such as Planck
and could be detected by future mm-wavelength interferometers (e.g., ALMA).

</DOC>
<DOC>
<DOCNO> 69806 </DOCNO>
Finite temperature corrections to weak rates prior to nucleosynthesis


  We have reexamined the electromagnetic corrections to the weak interaction
rates for the transformation of neutrons to protons, and protons to neutrons,
in the early universe, before freeze-out. We derive compact expressions for
these rates in terms of thermal expectation values of products of fields, and
we give explicit constructions of the terms to order e^2. We disagree in
several respects with results in the literature.

</DOC>
<DOC>
<DOCNO> 12382 </DOCNO>
Exact particle and kinetic energy densities for one-dimensional confined


  We propose a new method for the evaluation of the particle density and
kinetic pressure profiles in inhomogeneous one-dimensional systems of
non-interacting fermions, and apply it to harmonically confined systems of up
to N=1000 fermions. The method invokes a Green's function operator in
coordinate space, which is handled by techniques originally developed for the
calculation of the density of single-particle states from Green's functions in
the energy domain. In contrast to the Thomas-Fermi (local density)
approximation, the exact profiles under harmonic confinement show negative
local pressure in the tails and a prominent shell structure which may become
accessible to observation in magnetically trapped gases of fermionic alkali
atoms.

</DOC>
<DOC>
<DOCNO> 11828 </DOCNO>
Van Hove Singularities in the Quark-Gluon Plasma


  General arguments as well as different approximations for the in-medium quark
propagator in a quark-gluon plasma lead to quark dispersion relations that
exhibit a minimum in one branch (plasmino). This minimum causes Van Hove
singularities in the dilepton production rate and mesonic correlators, which
might have observable consequences.

</DOC>
<DOC>
<DOCNO> 39918 </DOCNO>
Searches for Compositeness at the Tevatron


  Quark-quark and quark-lepton searches for compositenss at the Fermilab
Tevatron are summarized. These are of the contact-interaction variety where
sqrt(s-hat) < the hypothesized mass scales, Lambda. Tevatron experiments limit
a variety of compositeness phenomena in the range from 1.9 to 8.3 TeV. These
limits result from measurements of: the Ht spectrum (D0), dijet mass (D0),
dijet angular distribution (CDF, D0), drell-yan production (CDF, D0), and the
Neutral Current to Charged Current ratio (CCFR/NuTeV).

</DOC>
<DOC>
<DOCNO> 117469 </DOCNO>
chi sup 2_ testing of optimal filters for gravitational wave signals: An


  We have implemented likelihood testing of the performance of an optimal
filter within the online analysis of AURIGA, a sub-Kelvin resonant-bar
gravitational wave detector. We demonstrate the effectiveness of this technique
in discriminating between impulsive mechanical excitations of the resonant-bar
and other spurious excitations. This technique also ensures the accuracy of the
estimated parameters such as the signal-to-noise ratio. The efficiency of the
technique to deal with non-stationary noise and its application to data from a
network of detectors are also discussed.

</DOC>
<DOC>
<DOCNO> 7724 </DOCNO>
SIN and SIS tunneling in cuprates


  We calculate the SIN and SIS tunneling conductances for the spin-fermion
model. We argue that at strong spin-fermion coupling, relevant to cuprates,
both conductances have dip features near the threshold frequencies when a
tunneling electron begin emitting propagating spin excitation. We argue that
the resonance spin frequency measured in neutron scattering can be inferred
from the tunneling data by analyzing the derivatives of SIN and SIS
conductances.

</DOC>
<DOC>
<DOCNO> 84827 </DOCNO>
What can we learn about GW Physics with an elastic spherical antenna?


  A general formalism is set up to analyse the response of an arbitrary solid
elastic body to an arbitrary metric Gravitational Wave perturbation, which
fully displays the details of the interaction antenna-wave. The formalism is
applied to the spherical detector, whose sensitivity parameters are thereby
scrutinised. A multimode transfer function is defined to study the amplitude
sensitivity, and absorption cross sections are calculated for a general metric
theory of GW physics. Their scaling properties are shown to be independent of
the underlying theory, with interesting consequences for future detector
design. The GW incidence direction deconvolution problem is also discussed,
always within the context of a general metric theory of the gravitational
field.

</DOC>
<DOC>
<DOCNO> 11424 </DOCNO>
Finite size scaling in the 2D XY-model and generalized universality


  In recent works (BHP), a generalized universality has been proposed, linking
phenomena as dissimilar as 2D magnetism and turbulence. To test these ideas, we
performed a MC study of the 2D XY-model. We found that the shape of the
probability distribution function for the magnetization M is non Gaussian and
independent of the system size --in the range of the lattice sizes studied--
below the Kosterlitz-Thoules temperature. However, the shape of these
distributions does depend on the temperature, contrarily to the BHP's claim.
This behavior is successfully explained by using an extended finite-size
scaling analysis and the existence of bounds for M.

</DOC>
<DOC>
<DOCNO> 169647 </DOCNO>
Photon-added one-photon and two-photon nonlinear coherent states


  From the photon-added one-photon nonlinear coherent states $a^{\dagger
m}|\alpha,f>$, we introduce a new type of nonlinear coherent states with
negative values of $m.$ The nonlinear coherent states corresponding to the
positive and negative values of $m$ are shown to be the result of nonunitarily
deforming the number states $|m>$ and $|0>$, respectively. As an example, we
study the sub-Poissonian statistics and squeezing effects of the photon-added
geometric states with negative values of $m$ in detail. Finally we investigate
the photon-added two-photon nonlinear coherent states and find that they are
still the two-photon nonlinear coherent states with certain nonlinear
functions.

</DOC>
<DOC>
<DOCNO> 8957 </DOCNO>
Near-field EM wave scattering from random self-affine fractal metal


  By means of rigorous numerical simulation calculations based on the Green's
theorem integral equation formulation, we study the near EM field in the
vicinity of very rough, one-dimensional self-affine fractal surfaces of Ag, Au,
and Cu (for both vacuum and water propagating media) illuminated by a p
polarized field. Strongly localized enhanced optical excitations (hot spots)
are found, with electric field intensity enhancements of close to 4 orders of
magnitude the incident one, and widths below a tenth of the incoming
wavelength. These effects are produced by roughness-induced surface-plasmon
polariton excitation. We study the characteristics of these optical excitations
as well as other properties of the surface electromagnetic field, such as its
statistics (probability density function, average and fluctuations), and their
dependence on the excitation spectrum (in the visible and near infrared). Our
study is relevant to the use of such self-affine fractals as surface-enhanced
Raman scattering substrates, where large local and average field enhancements
are desired.

</DOC>
<DOC>
<DOCNO> 69548 </DOCNO>
Multi-boson effects in Bose-Einstein interferometry and the multiplicity


  Multi-boson symmetrization effects on two-particle Bose-Einstein
interferometry are studied for ensembles with arbitrary multiplicity
distributions. This generalizes the previously studied case of a Poissonian
input multiplicity distribution. In the general case we find interesting
residual correlations which require a modified framework for extracting
information on the source geometry from two-particle correlation measurements.
In sources with high phase-space densities, multi-boson effects modify the
Hanbury Brown-Twiss (HBT) radius parameters and simultaneously generate strong
residual correlations. We clarify their effect on the correlation strength
(intercept parameter) and thus explain a variety of previously reported
puzzling multi-boson symmetrization phenomena. Using a class of analytically
solvable Gaussian source models, with and without space-momentum correlations,
we present a comprehensive overview of multi-boson symmetrization effects on
particle interferometry. For event ensembles of (approximately) fixed
multiplicity, the residual correlations lead to a minimum in the correlation
function at non-zero relative momentum, which can be practically exploited to
search, in a model-independent way, for multi-boson symmetrization effects in
high-energy heavy-ion experiments.

</DOC>
<DOC>
<DOCNO> 11403 </DOCNO>
Polygonization and plastic bending of whiskers induced by pulsed power


  Dynamics of bending of NaCl whisker is studied with use of high speed camera
VFU-1 synchronized with high power electron accelerator GIN-600. The dynamics
of bending turns to be non-monotonous and quite complicated. The figures of
etching of whisker after bombardment by electron beam are analysed, thin
polygonization in samples is found. The time of bending in experiment and time
of forming of dislocation walls computed on the base of theory of plastical
bending are compared.

</DOC>
<DOC>
<DOCNO> 12489 </DOCNO>
Spinon deconfinement above a finite energy gap in 2d Quantum Heisenberg


  The familiar spin-1/2 quantum Heisenberg antiferromanget in a 2d square
lattice is shown, within the non linear sigma model approximations, to be
another novel state of matter that has excitations with fractional quantum
numbers above a finite energy gap. 1-skyrmion with an energy $\approx 2\pi J$
is shown to be made of two `deconfined spinons' or `SU(2) vortices'. The many
skyrmion operator and the wave functions that we have found are strikingly
similar to quantum Hall quasi particle operators and wave functions. We also
predict the presence of finite energy `spin-S spinon' for a general spin-S
Heisenberg antiferromagnets in 2d. Some consequences are briefly discussed.

</DOC>
<DOC>
<DOCNO> 8380 </DOCNO>
High Reproduction Rate versus Sexual Fidelity


  We introduce fidelity into the bit-string Penna model for biological ageing
and study the advantage of this fidelity when it produces a higher survival
probability of the offspring due to paternal care. We attribute a lower
reproduction rate to the faithful males but a higher death probability to the
offspring of non-faithful males that abandon the pups to mate other females.
The fidelity is considered as a genetic trait which is transmitted to the male
offspring (with or without error). We show that nature may prefer a lower
reproduction rate to warrant the survival of the offspring already born.

</DOC>
<DOC>
<DOCNO> 39896 </DOCNO>
TESLA*HERA as Lepton (Photon)-Hadron Collider


  New facilities for particle and nuclear physics research, which will be
available due to constructing the TESLA linear electron-positron collider
tangentially to the HERA proton ring, are discussed.

</DOC>
<DOC>
<DOCNO> 8888 </DOCNO>
How the Replica-Symmetry-Breaking Transition Looks Like in Finite-Size


  Finite-size effects in the mean-field Ising spin glass and the mean-field
three-state Potts glass are investigated by Monte Carlo simulations. In the
thermodynamic limit, each model is known to exhibit a continuous phase
transition into the ordered state with a full and a one-step replica-symmetry
breaking (RSB), respectively. In the Ising case, Binder parameter g calculated
for various finite sizes remains positive at any temperature and crosses at the
transition point, while in the Potts case g develops a negative dip without
showing a crossing in the g>0 region. By contrast, non-self averaging
parameters always remain positive and show a clear crossing at the transition
temperature in both cases. Our finding suggests that care should be taken in
interpreting the numerical data of the Binder parameter, particularly when the
system exhibits a one-step-like RSB.

</DOC>
<DOC>
<DOCNO> 178789 </DOCNO>
Nucleon-nucleon scattering in a chiral constituent quark model


  We study the nucleon-nucleon interaction in a chiral constituent quark model
by using the resonating group method, convenient for treating the interaction
between composite particles. The calculated phase shifts for the 3S1 and 1S0
channels show the presence of a strong repulsive core due to the combined
effect of the quark interchange and the spin-flavour structure of the effective
quark-quark interaction. Such a symmetry structure stems from the pseudoscalar
meson exchange between the quarks and is a consequence of the spontaneous
breaking of the chiral symmetry. We perform single and coupled channel
calculations and show the role of coupling of the $\Delta\Delta$ and hidden
color CC channels on the behaviour of the phase shifts.

</DOC>
<DOC>
<DOCNO> 120337 </DOCNO>
HST infrared imaging polarimetry of Centaurus A: implications for the


  We report results from HST/NICMOS 2 micron imaging polarimetry of the central
region of Centaurus A. In the vicinity of the nucleus we observe a complex
polarization structure which we explain by a combination of scattering of
nuclear light and dichroic polarization associated with the dust lane. The
scattered nuclear radiation is found in an angular region which extends over ~
70 degrees and thus it does not originate from a highly collimated beam, but is
associated with more omni-directional nuclear illumination. These observations
also show the presence of an unresolved, highly polarized (P = 11.1 %) nuclear
source whose polarization angle PA = 148.2 degrees is perpendicular to the jet
axis. We set an upper limit of 0.04'' (~0.8 pc) to its extent. The observed
nuclear polarization is naturally accounted for if we are observing scattered
light from an otherwise obscured nucleus provided that both the scattering
region and the occulting torus are extremely compact, with an outer radius of
less than ~ 1 pc. Alternatively, we might be directly seeing the infrared
counterpart of the radio core, similar to those found in other low luminosity
radio-galaxies observed with HST. We discuss these results in the framework of
the FRI / BL Lac unifying model.

</DOC>
<DOC>
<DOCNO> 11925 </DOCNO>
Kinetics of Coalescence, Annihilation, and the q-State Potts Model in


  The kinetics of the q-state Potts model in the zero temperature limit in one
dimension is analyzed exactly through a generalization of the method of empty
intervals, previously used for the analysis of diffusion-limited coalescence,
A+A->A. In this new approach, the q-state Potts model, coalescence, and
annihilation (A+A->0) all satisfy the same diffusion equation, and differ only
in the imposed initial condition.

</DOC>
<DOC>
<DOCNO> 100613 </DOCNO>
Semi-Riemannian submersions from real and complex pseudo-hyperbolic


  We classify the semi-Riemannian submersions from a pseudo-hyperbolic space
onto a Riemannian manifold under the assumption that the fibres are connected
and totally geodesic. Also we obtain the classification of the semi-Riemannian
submersions from a complex pseudo-hyperbolic space onto a Riemannian manifold
under the assumption that the fibres are complex, connected and totally
geodesic submanifolds.

</DOC>
<DOC>
<DOCNO> 151428 </DOCNO>
On the General Structure of the Non-Abelian Born-Infeld Action


  We discuss the general structure of the non-abelian Born-Infeld action,
together with all of the alpha-prime derivative corrections, in flat
D-dimensional space-time. More specifically, we show how the connection between
open strings propagating in background magnetic fields and gauge theories on
non-commutative spaces can be used to constrain the form of the effective
action for the massless modes of open strings at week coupling. In particular,
we exploit the invariance in form of the effective action under a change of
non-commutativity scale of space-time to derive algebraic equations relating
the various terms in the alpha- prime expansion. Moreover, we explicitly solve
these equations in the simple case D=2, and we show, in particular, how to
construct the minimal invariant derivative extension of the NBI action.

</DOC>
<DOC>
<DOCNO> 117465 </DOCNO>
The Chemical Composition of Carbon Stars II: The J-type stars


  Abundances of Li, heavy elements and carbon isotope ratios have been measured
in 12 J-type galactic carbon stars. The abundance analysis shows that in these
stars the abundances of s-process elements with respect to the metallicity are
nearly normal. Tc is not present in most of them, although upper limits have
been derived for WZ Cas and WX Cyg, perhaps two SC-type rather than J-type
carbon stars. The Rb abundances, obtained from the resonance 7800 {\AA} Rb I
line, are surprisingly low, probably due to strong non-LTE effects in the
formation of this line in cool carbon-rich stars. Lithium and $^{13}$C are
found to be enhanced in all the stars. These results together with the nitrogen
abundances and oxygen isotope ratios measured by Lambert et al. (1986) and
Harris et al. (1987) are used to discuss the origin of J-stars. The luminosity
and variability class of the stars studied would indicate that they are low
mass (M$\leq 2-3$ M$_\odot$), less evolved objects than the normal carbon
stars, although the presence of some luminous (M$_{bol}<-5.5$) J-stars in our
galaxy (WZ Cas may be an example) and in other galaxies, suggests the existence
of at least two types of J-stars, with different formation scenarios depending
upon the initial mass of the parent star. Standard evolutionary AGB models are
difficult to reconcile with all the observed chemical characteristics. In fact,
they suggest the existence of an extra-mixing mechanism which transports
material from the convective envelope down to hotter regions where some nuclear
burning occurs. This mechanism would act preferably on the early-AGB phase in
low-mass stars. Mixing at the He-core flash and the binary system hypothesis
are also discussed as alternatives to the above scenario.

</DOC>
<DOC>
<DOCNO> 150803 </DOCNO>
String Theory and Noncommutative Field Theories at One Loop


  By exploiting the boundary state formalism we obtain the string correlator
between two internal points on the one loop open string world-sheet in the
presence of a constant background $B$-field. From this derivation it is clear
that there is an ambiguity when one tries to restrict the Green function to the
boundary of the surface. We fix this ambiguity by showing that there is a {\em
unique} form for the correlator between two points on the boundary which
reproduces the one loop field theory results of different noncommutative field
theories. In particular, we present the derivation of one loop diagrams for
$\phi^3_6$ and $\phi^4_4$ scalar interactions and for Yang--Mills theory. From
the 2-point function we are able to derive the one loop $\beta$-function for
noncommutative gauge theory.

</DOC>
<DOC>
<DOCNO> 102400 </DOCNO>
The Deligne-Simpson problem for zero index of rigidity


  We consider the {\em Deligne-Simpson problem}:
  {\em Give necessary and sufficient conditions for the choice of the conjugacy
classes $c_j\subset gl(n,{\bf C})$ or $C_j\subset GL(n,{\bf C})$, $j=1,...,
p+1$, so that there exist irreducible $(p+1)$-tuples of matrices $A_j\in c_j$
whose sum is 0 or of matrices $M_j\in C_j$ whose product is $I$.} The matrices
$A_j$ (resp. $M_j$) are interepreted as matrices-residua of Fuchsian linear
systems (resp. as monodromy operators of regular systems) on Riemann's sphere.
We consider the case when the sum of the dimensions of the conjugacy classes
$c_j$ or $C_j$ is $2n^2$ and we prove a theorem of non-existence of such
irreducible $(p+1)$-tuples.

</DOC>
<DOC>
<DOCNO> 40269 </DOCNO>
Width difference in the Bs system from lattice HQET


  We present recent results for the prediction of the Bs lifetime difference
from lattice Heavy Quark Effective Theory simulations. In order to get a
next-to-leading order result we have calculated the matching between QCD and
HQET and the two loop anomalous dimension in the HQET for all the \Delta B=2
operators, in particular for the operators which enter in the width difference.
We obtain for the Bs lifetime difference, (\Delta\Gamma_Bs/\Gamma_Bs)=(5.1+/-
1.9+/- 1.7)10^(-2).

</DOC>
<DOC>
<DOCNO> 11267 </DOCNO>
Evidence of two-electron tunneling interference in Nb/InAs junctions


  The impact of junction transparency in driving phase-coherent charge transfer
across diffusive semiconductor-superconductor junctions is demonstrated. We
present conductivity data for a set of Nb-InAs junctions differing only in
interface transparency. Our experimental findings are analyzed within the
quasi-classical Green-function approach and unambiguously show the physical
processes giving rise to the observed excess zero-bias conductivity.

</DOC>
<DOC>
<DOCNO> 39793 </DOCNO>
Physics at e-e- Colliders


  An overview of the physics motivations for e-e- colliders is presented.

</DOC>
<DOC>
<DOCNO> 116642 </DOCNO>
Golden Bars of Consensus and the Truth Quark


  Scientists are imprisoned by Golden Bars of Consensus, says Burton Richter
(hep-ex/0001012). A case in point is the mass of the Truth Quark. The consensus
analysis of the experimental data indicates that the mass of the Truth Quark is
about 170 GeV. On the other hand, an alternative analysis of the same data
indicates that the mass of the Truth Quark is about 130 GeV. If the design of
future experiments, including trigger, event selection, data analysis
procedures, error analysis, etc., takes into account only the consensus value,
and if the consensus value happens to be incorrect, then results of future
experiments might be compromised.

</DOC>
<DOC>
<DOCNO> 150688 </DOCNO>
On Orientifolds, Discrete Torsion, Branes and M Theory


  We find some lifts to M theory of orientifold and orbifold planes including
the O1, O3 and O5 planes of Type IIB and their transformations under SL(2,Z).
The possible discrete torsion variants (or K theory classes) are explored, and
are interpreted as arising from brane intersections with planes. We find new
variants of the O0 and of an orbifold line (OF1) and determine their tensions
in some cases. A systematic review of orientifolds, M orientifolds, and known M
lifts, with some new clarifications is included together with a discussion of
the role of T duality.

</DOC>
<DOC>
<DOCNO> 68646 </DOCNO>
Quintessential Adjustment of the Cosmological Constant


  We construct a time dependent adjustment mechanism for the cosmological
"constant" which could be at work in a late Friedmann-Robertson-Walker universe
dominated by quintessence and matter. It makes use of a Brans-Dicke field that
couples to the evolving standard-model vacuum energy density. Our explicit
model possesses a stable late-time solution with a fixed ratio of matter and
field energy densities. No fine tuning of model parameters or initial
conditions is required.

</DOC>
<DOC>
<DOCNO> 120169 </DOCNO>
Distribution of dust from Kuiper belt objects


  (Abridged) Using an efficient computational approach, we have reconstructed
the structure of the dust cloud in the Solar system between 0.5 and 100 AU
produced by the Kuiper belt objects. Our simulations offer a 3-D physical model
of the `kuiperoidal' dust cloud based on the distribution of 280 dust particle
trajectories produced by 100 known Kuiper belt objects ; the resulting 3-D grid
consists of $1.9\times 10^6$ cells containing $1.2\times 10^{11}$ particle
positions. The following processes that influence the dust particle dynamics
are taken into account: 1) gravitational scattering on the eight planets
(neglecting Pluto); 2) planetary resonances; 3) radiation pressure; and 4) the
Poynting-Robertson (P-R) and solar wind drags. We find the dust distribution
highly non-uniform: there is a minimum in the kuiperoidal dust between Mars and
Jupiter, after which both the column and number densities of kuiperoidal dust
sharply increase with heliocentric distance between 5 and 10 AU, and then form
a plateau between 10 and 50 AU. Between 25 and 45 AU, there is an appreciable
concentration of kuiperoidal dust in the form of a broad belt of mostly
resonant particles associated with Neptune. In fact, each giant planet
possesses its own circumsolar dust belt consisting of both resonant and
gravitationally scattered particles. As with the cometary belts simulated in
our related papers (Ozernoy, Gorkavyi, & Taidakova 2000a,b), we reveal a
complex resonant structure of the dust belts containing rich families of
resonant peaks and gaps. An important result is that both the column and number
dust density are more or less flat between 10 and 50 AU, which might explain
the surprising data obtained by Pioneers 10 & 11 and Voyager that the dust
number density remains approximately distance-independent in this region.

</DOC>
<DOC>
<DOCNO> 150676 </DOCNO>
Measurability of the non-minimal coupling


  The "measurability" of the non-minimal coupling is discussed in the context
of the effective field theory of gravity. Although there is no obvious motive
for excluding a non-minimal scalar coupling from the theory, we conclude that
for reasonable values of the coupling constant it makes only a very small
correction.

</DOC>
<DOC>
<DOCNO> 80588 </DOCNO>
Instantons and Gribov Copies in the Maximally Abelian Gauge


  We calculate the Faddeev-Popov operator corresponding to the maximally
Abelian gauge for gauge group SU(N). Specializing to SU(2) we look for explicit
zero modes of this operator. Within an illuminating toy model (Yang-Mills
mechanics) the problem can be completely solved and understood. In the field
theory case we are able to find an analytic expression for a normalizable zero
mode in the background of a single `t Hooft instanton. Accordingly, such an
instanton corresponds to a horizon configuration in the maximally Abelian
gauge. Possible physical implications are discussed.

</DOC>
<DOC>
<DOCNO> 120560 </DOCNO>
Three Dimensional Magneto-Hydrodynamical Modeling of Planetary Nebuale ~


  This work presents three dimensional, magneto-hydrodynamical simulations of
the formation and early evolution of a subgroup of planetary nebulae that
exhibit a variety of point-symmetric structures. For bipolar nebulae, the
formation of point-symmetric nebular shapes along the inner borders of their
opposing lobes and/or collimated outflows or jets internal or external to their
cavities, is reproduced by considering a steady misalignment of the magnetic
collimation axis with respect to the symmetry axis of the bipolar wind outflow,
defined perpendicular to the equatorial density enhancement. Elliptical
planetary nebulae with ansae displaced from the symmetry axis in
point-symmetric fashion are reproduced through the same process by reducing the
equatorial density enhancement. This mechanism represents an alternative
explanation to some cases where morphological appearances give the impression
of the action of a symmetric, rotating or precessing jet from the central
source. The computational survey reveals that jet formation is detected only
for dense enough winds with mass loss rates $\gtrsim 10^{-7}$ \Moy. For lower
mass loss rates the jets tend to vanish leaving behind only ansae-like
structures at the tips of the lobes, as observed in some cases. The results are
rather independent of the wind terminal velocity, since magnetized bubbles
behave adiabatically for low wind velocities ($\simeq$ $100 \kms$), which in
the absence of a magnetic field would behave as momentum driven.

</DOC>
<DOC>
<DOCNO> 10394 </DOCNO>
Fine structure of excitons in a quantum well in the presence of a


  The trapping of excitons in a semiconductor quantum well due to a circular
symmetric nonhomogeneous magnetic field is studied. The effect of the spin
state of the exciton on its trapping energy is analyzed, and the importance of
the interaction of the orbital and spin Zeeman effect as compared to the
diamagnetic term in the exciton Hamiltonian is emphasized. Magnetic field
profiles are considered, which can experimentally be created through the
deposition of ferromagnetic disks on top of a semiconductor heterostructure.
This setup gives rise to a magnetic dipole type of profile in the $xy$ plane of
the exciton motion. We find that the spin direction of the exciton influences
its localization by changing the confinement region in the effective potential.
The exciton confinement increases with magnetic field intensity, and this is
more pronounced when the exciton g-factor is different from zero. The numerical
calculations are performed for GaAs/Al$_{x}$Ga$_{1-x}$As quantum wells and we
show that it open up a new realistic path for experiments designed to probe
exciton trapping in semiconductors.

</DOC>
<DOC>
<DOCNO> 71329 </DOCNO>
Infinite symmetries in the Skyrme model


  We show that the Skyrme theory possesses a submodel with an infinite number
of local conserved currents. The constraints leading to the submodel explore a
decomposition of SU(2) with a complex field parametrizing the symmetric space
SU(2)/U(1) and a real field in the direction of U(1). We demonstrate that the
Skyrmions of topological charges $\pm 1$ belong to such integrable sector of
the theory. Our results open ways to the development of exact methods,
compensating for the non-existence of a BPS type sector in the Skyrme theory.

</DOC>
<DOC>
<DOCNO> 39839 </DOCNO>
A study of the eta eta channel produced in central pp interactions at


  The reaction pp -> pf (eta eta) ps has been studied at 450 GeV/c. For the
first time a partial wave analysis of the centrally produced eta eta system has
been performed. Signals for the f0(1500), f0(1710) and f2(2150) are observed
and the decay branching fractions of these states are determined.

</DOC>
<DOC>
<DOCNO> 100676 </DOCNO>
Hidden Virasoro Symmetry of (Soliton Solutions of) the Sine Gordon


  We present a construction of a Virasoro symmetry of the sine-Gordon (SG)
theory. It is a dynamical one and has nothing to do with the space-time
Virasoro symmetry of 2D CFT. Although it is clear how it can be realized
dyrectly in the SG field theory, we are rather concerned here with the
corresponding N-soliton solutions. We present explicit expressions for their
infinithesimal transformations and show that they are local in this case. Some
preliminary stages about the quantization of the classical results presented in
this paper are also given.

</DOC>
<DOC>
<DOCNO> 119337 </DOCNO>
BeppoSAX broad-band observations of low-redshift quasars: Spectral


  We present results from BeppoSAX observations of 10 low redshift quasars. The
quasars are part of the Laor et al. (1997) sample of 23 optically selected PG
quasars with redshift <0.4 and low Galactic absorption along the line of sight.
Significant spectral curvature is detected for the 6 quasars with the highest
signal to noise ratio in their low energy spectra. The average curvature can be
parameterized as a flattening of the underlying power law by Delta_alpha ~ 0.5
above ~1 keV. We find that quasars with a steeper soft X-ray (0.1-2 keV)
spectrum tend to be steeper also at higher (2-10 keV) energies. The
distribution of the best fit 2-10 keV slopes is similar to that found for other
radio-quiet AGN and characterized by a large dispersion around the mean:
alpha_E ~ 1.0+/-0.3. Iron K_alpha lines are detected in 4 quasars. In the
narrow-line quasar PG 1115+407, the rest frame line energy (6.69+/-0.11 keV)
and equivalent width (580+/-280 eV) are consistent with those found in a few
low redshift narrow-line Seyfert 1 galaxies (NLSy1). This, together with the
similarity of the 0.1-10 keV X-ray continuum, suggests that this quasar is the
higher redshift and luminosity analog of a NLSy1. In the broad line quasar PG
0947+396, the rest-frame line energy suggests fluorescence from cold iron. The
line equivalent width (> 400 eV) is however about 2-3 times higher than that
usually found in Seyfert 1 galaxies. The high energy power-law slopes and the
iron line emission properties seem to be unrelated to the X-ray luminosity.

</DOC>
<DOC>
<DOCNO> 121466 </DOCNO>
Accretion disc coronae as magnetic reservoirs


  Most astrophysical sources powered by accretion onto a black hole, either of
stellar mass or supermassive, when observed with hard X-rays show signs of a
hot Comptonizing component in the flow, the so-called corona, with observed
temperatures and optical depths lying in a narrow range (0.1 < \tau < 1 and
1x10^9 K < T < 3x10^9 K). Here we argue that these facts constitute strong
supporting evidence for a magnetically-dominated corona. We show that the
inferred thermal energy content of the corona, in all black hole systems, is
far too low to explain their observed hard X-ray luminosities, unless either
the size of the corona is at least of the order of 10^3 Schwarzschild radii, or
the corona itself is in fact a reservoir, where the energy is mainly stored in
the form of a magnetic field generated by a sheared rotator (probably the
accretion disc). We briefly outline the main reasons why the former possibility
is to be discarded, and the latter preferred.

</DOC>
<DOC>
<DOCNO> 122209 </DOCNO>
The equilibrium of dense plasma in a gravity field


  The equilibrium of dense plasma in a gravity field and problem of a
gravity-induced electric polarization in this matter are discussed. The
calculation for metals performed before shows that both - the gravity-induced
compressive strain and the gravity-induced electric field - are inversely
proportional to their Young moduli. The calculation for high dense plasma,
where Young modulus is equal to zero, shows that there is another effect: each
cell of this plasma inside a celestial body in own gravity field obtains the
small positive electric charge. It happens as heavy ions sag on to light
electron clouds. A celestial body stays electrically neutral as a whole,
because the negative electric charge concentrates on its surface. The
gravity-induced positive volume charge is very small, its order of magnitude
equals to $10^{-18}e$ per atom only. But it is sufficient for the complete
conterbalancing of the gravity force.

</DOC>
<DOC>
<DOCNO> 151099 </DOCNO>
Bound States of a Minimally Interacting Spin-0 and Spin-1/2 Constituent


  Bound-state solutions are obtained numerically in the instantaneous
approximation for a spin-0 and spin-1/2 constituent that interact via minimal
electrodynamics. To solve the integral equations in momentum space, a method is
developed for integrating over the logarithmic singularity in kernels, making
it possible to use basis functions that essentially automatically satisfy the
boundary conditions. For bound-state solutions that decrease rapidly at small
and large values of momentum, accurate solutions are obtained with
significantly fewer basis functions when the solution is expanded in terms of
these more general basis functions. The presence of a derivative coupling in
single-photon exchange complicates the construction of the Bethe-Salpeter
equation in the instantaneous approximation and, in the nonrelativistic limit,
gives rise to an additional electrostatic potential term that is second order
in the coupling constant and decreases as the square of the distance between
constituents.

</DOC>
<DOC>
<DOCNO> 120388 </DOCNO>
The Influence of Central Black Holes on Gravitational Lenses


  Recent observations indicate that many if not all galaxies host massive
central black holes. In this paper we explore the influence of black holes on
the lensing properties. We model the lens as an isothermal ellipsoid with a
finite core radius plus a central black hole. We show that the presence of the
black hole substantially changes the critical curves and caustics. If the black
hole mass is above a critical value, then it will completely suppress the
central images for all source positions. Realistic central black holes likely
have masses below this critical value. Even in such sub-critical cases, the
black hole can suppress the central image when the source is inside a zone of
influence, which depends on the core radius and black hole mass. In the
sub-critical cases, an additional image may be created by the black hole in
some regions, which for some radio lenses may be detectable with
high-resolution and large dynamic-range VLBI maps. The presence of central
black holes should also be taken into account when one constrains the core
radius from the lack of central images in gravitational lenses.

</DOC>
<DOC>
<DOCNO> 8364 </DOCNO>
The Statistical Mechanics of Membranes


  The fluctuations of two-dimensional extended objects membranes is a rich and
exciting field with many solid results and a wide range of open issues. We
review the distinct universality classes of membranes, determined by the local
order, and the associated phase diagrams. After a discussion of several
physical examples of membranes we turn to the physics of crystalline (or
polymerized) membranes in which the individual monomers are rigidly bound. We
discuss the phase diagram with particular attention to the dependence on the
degree of self-avoidance and anisotropy. In each case we review and discuss
analytic, numerical and experimental predictions of critical exponents and
other key observables. Particular emphasis is given to the results obtained
from the renormalization group epsilon-expansion. The resulting renormalization
group flows and fixed points are illustrated graphically. The full technical
details necessary to perform actual calculations are presented in the
Appendices. We then turn to a discussion of the role of topological defects
whose liberation leads to the hexatic and fluid universality classes. We finish
with conclusions and a discussion of promising open directions for the future.

</DOC>
<DOC>
<DOCNO> 119163 </DOCNO>
X-ray observation of radio supernova SN1979C by ASCA


  We report on the X-ray observation of the radio selected supernova SN1979C
carried out with ASCA in December 1997. The supernova of type II$_{L}$ was
first observed in the optical and occurred in the weakly barred, almost face on
spiral galaxy NGC 4321 (M100) which is at a distance of 17.1 Mpc, and contains
at least three other supernovae discovered in this century. No point source was
detected at the radio position of SN1979C in a 3' diameter half power response
circle in a 27.3 ks SIS exposure. The background and galaxy subtracted SN
signal had a 3$\sigma$ upper limit to the count rate of 1.2$\times 10^{-3}$ cps
in the full ASCA SIS band (0.4-10.0 keV). These measurements give the first
ever x-ray flux limit of a Type II$_{L}$ SN in the higher energy band ($\geq$ 2
keV) which is an important diagnostic of the {\it outgoing} shock wave
ploughing through the circumstellar medium.

</DOC>
<DOC>
<DOCNO> 72176 </DOCNO>
Fermion mass effects in e+e- --> 4f and e+e- --> 4f gamma with cuts


  The fermion mass effects in e+ e- --> 4f and in the corresponding
bremsstrahlung reactions in the presence of realistic cuts are studied. It is
shown that, for some four--fermion final states, the mass effects become
sizeable to the extent that they may affect the accuracy of theoretical
predictions which is required to be better than 1%.

</DOC>
<DOC>
<DOCNO> 9941 </DOCNO>
Cellular solid behaviour of liquid crystal colloids. 2. Mechanical


  This paper presents the results of a rheological study of thermotropic
nematic colloids aggregated into cellular structures. Small sterically
stabilised PMMA particles dispersed in a liquid crystal matrix densely pack on
cell interfaces, but reversibly mix with the matrix when the system is heated
above Tni. We obtain a remarkably high elastic modulus, G'~10^5 Pa, which is a
nearly linear function of particle concentration. A characteristic yield stress
is required to disrupt the continuity of cellular structure and liquify the
response. The colloid aggregation in a ``poor nematic'' MBBA has the same
cellular morphology as in the ``good nematic'' 5CB, but the elastic strength is
at least an order of magnitude lower. These findings are supported by
theoretical arguments based on the high surface tension interfaces of a
foam-like cellular system, taking into account the local melting of nematic
liquid and the depletion locking of packed particles on interfaces.

</DOC>
<DOC>
<DOCNO> 100988 </DOCNO>
Efficient fundamental cycles of cusped hyperbolic manifolds


  Let N be a manifold (with boundary) of dimension at least 3, such that its
interior admits a hyperbolic metric of finite volume. We discuss the possible
limits arising from sequences of relative fundamental cycles approximating the
simplicial volume.
  As applications, we extend results of Jungreis and Calegari from closed
hyperbolic to finite-volume hyperbolic manifolds: a) strict subadditivity of
simplicial volume with respect to isometric glueing along geodesic surfaces,
and b) nontriviality of the foliated Gromov norm for "most" foliations with
two-sided branching.

</DOC>
<DOC>
<DOCNO> 99982 </DOCNO>
Mahler measure, links and homology growth


  Let l be a link of d components. For every finite-index lattice in Z^d there
is an associated finite abelian cover of S^3 branched over l. We show that the
order of the torsion subgroup of the first homology of these covers has
exponential growth rate equal to the logarithmic Mahler measure of the
Alexander polynomial of l, provided this polynomial is nonzero. Our proof uses
a theorem of Lind, Schmidt and Ward on the growth rate of connected components
of periodic points for algebraic Z^d-actions.

</DOC>
<DOC>
<DOCNO> 117458 </DOCNO>
Theory and Observations of Type I X-Ray Bursts from Neutron Stars


  I review our understanding of the thermonuclear instabilities on accreting
neutron stars that produce Type I X-Ray bursts. I emphasize those observational
and theoretical aspects that should interest the broad audience of this
meeting. The easily accessible timescales of the bursts (durations of tens of
seconds and recurrence times of hours to days) allow for a very stringent
comparison to theory. The largest discrepancy (which was found with EXOSAT
observations) is the accretion rate dependence of the Type I burst properties.
Bursts become less frequent and energetic as the global accretion rate
increases, just the opposite of what the spherical theory predicts. I present a
resolution of this issue by taking seriously the observed dependence of the
burning area on the global accretion rate, which implies that as the accretion
rate increases, the accretion rate per unit area decreases. This resurrects the
unsolved problem of knowing where the freshly accreted material accumulates on
the star, equally relevant to the likely signs of rotation during the bursts
summarized by Swank at this meeting. I close by highlighting the Type I bursts
from GS 1826-238 that were found with BeppoSAX and RXTE. Their energetics,
recurrence times and temporal profiles clearly indicate that hydrogen is being
burned during these bursts, most likely by the rapid-proton (rp) process.

</DOC>
<DOC>
<DOCNO> 10934 </DOCNO>
Phase diagram of polymer blends in confined geometry


  Within self-consistent field theory we study the phase behavior of a
symmetrical binary AB polymer blend confined into a thin film. The film
surfaces interact with the monomers via short range potentials. One surface
attracts the A component and the corresponding semi-infinite system exhibits a
first order wetting transition. The surface interaction of the opposite surface
is varied as to study the crossover from capillary condensation for symmetric
surface fields to the interface localization/delocalization transition for
antisymmetric surface fields. In the former case the phase diagram has a single
critical point close to the bulk critical point. In the latter case the phase
diagram exhibits two critical points which correspond to the prewetting
critical points of the semi-infinite system. Only below a triple point there is
a single two phase coexistence region. The crossover between these
qualitatively different limiting behaviors occurs gradually, however, the
critical temperature and the critical composition exhibit a non-monotonic
dependence on the surface field. The dependence of the phase behavior for
antisymmetric boundaries is studied as a function of the film thickness and the
strength of the surface interactions. Upon reducing the film thickness or
decreasing the strength of the surface interactions we can change the order of
the interface localization/delocalization transition from first to second. The
role of fluctuations is explored via Monte Carlo simulations of a coarse
grained lattice model. Close to the (prewetting) critical points we observe 2D
Ising critical behavior. At lower temperatures capillary waves of the AB
interface lead to a pronounced dependence of the effective interface potential
on the lateral system size.

</DOC>
<DOC>
<DOCNO> 8053 </DOCNO>
Economy of scales in R&D with block-busters


  Are large scale research programs that include many projects more productive
than smaller ones with fewer projects? This problem of economy of scale is
particularly relevant for understanding recent mergers in particular in the
pharmaceutical industry. We present a quantitative theory based on the
characterization of distributions of discounted sales S resulting from new
products. Assuming that these complementary cumulative distributions have fat
tails with approximate power law structure S^{-a}, we demonstrate that economy
of scales are automatically realized when the exponent a is less than one.
Empirical evidence suggests that the exponent a is approximately equal to 2/3
for the pharmaceutical industry.

</DOC>
<DOC>
<DOCNO> 85025 </DOCNO>
Gravitational Wave Damping of Neutron Star Wobble


  We calculate the effect of gravitational wave (gw) back-reaction on realistic
neutron stars (NS's) undergoing torque-free precession. By `realistic' we mean
that the NS is treated as a mostly-fluid body with an elastic crust, as opposed
to a rigid body. We find that gw's damp NS wobble on a timescale tau_{theta}
approx 2 x 10^5 yr [10^{-7}/(DId/I_0)]^2 (kHz/ nu_s)^4, where nu_s is the spin
frequency and DId is the piece of the NS's inertia tensor that "follows" the
crust's principal axis (as opposed to its spin axis). We give two different
derivations of this result: one based solely on energy and angular momentum
balance, and another obtained by adding the Burke-Thorne radiation reaction
force to the Newtonian equations of motion. This problem was treated long ago
by Bertotti and Anile (1973), but their claimed result is wrong. When we
convert from their notation to ours, we find that their tau_{theta} is too
short by a factor of order 10^5 for typical cases of interest, and even has the
wrong sign for DId negative. We show where their calculation went astray.

</DOC>
<DOC>
<DOCNO> 102721 </DOCNO>
Automorphisms of manifolds


  This is a survey paper on spaces of automorphisms of manifolds and spaces of
manifolds in a fixed homotopy type. It describes the main theorems of
traditional surgery theory, but also the main theorems of pseudoisotopy theory,
alias concordance theory, Waldhausen style. It culminates in (an outline of) a
synthesis of these two theories, producing algebraic models, valid in a stable
range, for spaces of manifolds in a fixed homotopy type. This is inspired by
earlier work of Burghelea-Lashof and Hatcher. The algebraic models are a mix of
algebraic L-theory and algebraic K-theory.

</DOC>
<DOC>
<DOCNO> 117257 </DOCNO>
The Case for 2-D Turbulence in Antarctic Data


  In this paper we examine the data that was collected at Haley Station in
Antarctica on June 22, 1987. Using a test devised by Dewan we interpret the
flow as one which represents two-dimensional turbulence. We also construct a
model to interpret the spectrum of this data which is almost independent of the
wave number for a range of frequencies.

</DOC>
<DOC>
<DOCNO> 9944 </DOCNO>
Bias and temperature dependence of the 0.7 conductance anomaly in


  The 0.7 (2e^2/h) conductance anomaly is studied in strongly confined, etched
GaAs/GaAlAs quantum point contacts, by measuring the differential conductance
as a function of source-drain and gate bias as well as a function of
temperature. We investigate in detail how, for a given gate voltage, the
differential conductance depends on the finite bias voltage and find a
so-called self-gating effect, which we correct for. The 0.7 anomaly at zero
bias is found to evolve smoothly into a conductance plateau at 0.85 (2e^2/h) at
finite bias. Varying the gate voltage the transition between the 1.0 and the
0.85 (2e^2/h) plateaus occurs for definite bias voltages, which defines a gate
voltage dependent energy difference $\Delta$. This energy difference is
compared with the activation temperature T_a extracted from the experimentally
observed activated behavior of the 0.7 anomaly at low bias. We find \Delta =
k_B T_a which lends support to the idea that the conductance anomaly is due to
transmission through two conduction channels, of which the one with its subband
edge \Delta below the chemical potential becomes thermally depopulated as the
temperature is increased.

</DOC>
<DOC>
<DOCNO> 10911 </DOCNO>
Spinless fermions ladders at half filling


  We study a half filled ladder of spinless fermions. We show that contrarily
to a single chain, the ladder becomes a Mott insulator for arbitrarily small
repulsive interactions. We obtain the full phase diagram and physical
quantities such as the charge gap. We show that there is only a single
insulating phase for repulsive interactions, regardless of the stength of the
interchain hopping and single chain Mott gap. There is thus no
confinement-deconfinement transition in this system but a simple crossover. We
show that upon doping the system becomes a Luttinger liquid with a universal
parameter $K=1/2$ different from the one of the single chain ($K=1/4$).

</DOC>
<DOC>
<DOCNO> 151883 </DOCNO>
Tachyon condensation in unstable type I D-brane systems


  Type I string theory provides eight classes of unstable D-brane systems. We
determine the gauge group and tachyon spectrum for each one, and thereby
describe the gauge symmetry breaking pattern in the low-energy world-volume
field theory. The topologies of the resulting coset vacuum manifolds are
related to the real K-theory groups KO^{-n}, extending the known relations
between the Type II classifying spaces BU and U and the complex K-theory groups
K^0 and K^{-1}. We also comment on the role of the background D9-branes.

</DOC>
<DOC>
<DOCNO> 11712 </DOCNO>
Large Predicted Self-Field Critical Current Enhancements In


  A transport current distribution over a wide superconducting sheet is shown
to strongly change in a presence of bulk magnetic screens of a soft magnet with
a high permeability. Depending on the geometry, the effect may drastically
suppress or protect the Meissner state of the sheet through the enhancement or
suppression of the edge barrier critical current. The total transport current
in the magnetically screened Meissner state is expected to compete with the
critical current of the flux-filled sheet only for samples whose critical
current is initially essentially controlled by the edge barrier effect.

</DOC>
<DOC>
<DOCNO> 116532 </DOCNO>
Puzzle of the constancy of fundamental constants


  We discuss experiments and observations aimed at testing the possible
space-time variability of fundamental physical constants, predicted by the
modern theory. Specifically, we consider two of the dimensionless physical
parameters which are important for atomic and molecular physics: the
fine-structure constant and the electron-to-proton mass ratio. We review the
current status of such experiments and critically analyze recent claims of a
detection of the variability of the fine-structure constant on the cosmological
time scale. We stress that such a detection remains to be checked by future
experiments and observations. The tightest of the firmly established upper
limits read that the considered constants could not vary by more than 0.015% on
the scale of 10 Gigayears.

</DOC>
<DOC>
<DOCNO> 10241 </DOCNO>
N\'eel ordered versus quantum disordered behavior in doped spin-Peierls


  I consider a theoretical description of recent experiments on doping the
spin-Peierls compound CuGeO$_3$ and the Haldane gap compounds
PbNi$_2$V$_2$O$_8$ and Y$_2$BaNiO$_5$. The effective theory is the one of
randomly distributed spin-$1/2$ moments interacting with an exchange decaying
exponentially with distance. The model has two phases in the (doping,
interchain coupling) plane: (i) A N\'eel ordered phase at small doping; (ii) A
quantum disordered phase at larger doping and small interchain interactions.
The spin-Peierls compound CuGeO$_3$ and the Haldane gap Nickel oxides
PbNi$_2$V$_2$O$_8$ and Y$_2$BaNiO$_5$ fit well into this phase diagram. At
small temperature, the N\'eel phase is found to be reentrant into the quantum
disordered region. The N\'eel transition relevant for CuGeO$_3$ and
PbNi$_2$V$_2$O$_8$ can be described in terms of a classical disordered model. A
simplified version of this model is introduced, and is solved on a hierarchical
lattice structure, which allows to discuss the renormalization group flow of
the model. It is found that the system looks non disordered at large scale,
which is not against available susceptibility experiments. In the quantum
disordered regime relevant for Y$_2$BaNiO$_5$, the two spin model and the
cluster RG in the 1D regime show a power law susceptibility, in agreement with
recent experiments on Y$_2$BaNiO$_5$. It is found that there is a succession of
two distinct quantum disordered phases as the temperature is decreased. The
classical disordered model of the doped spin-$1$ chain contains already a
physics relevant to the quantum disordered phase.

</DOC>
<DOC>
<DOCNO> 70074 </DOCNO>
Dispersion relation formalism for virtual Compton scattering and the


  A dispersion relation formalism for the virtual Compton scattering (VCS)
reaction on the proton is presented, which for the first time allows a
dispersive evaluation of 4 generalized polarizabilities at a four-momentum
transfer $Q^2 \leq$ 0.5 GeV$^2$. The dispersive integrals are calculated using
a state-of-the-art pion photo- and electroproduction analysis. The dispersion
formalism provides a new tool to analyze VCS experiments above pion threshold,
thus increasing the sensitivity to the generalized polarizabilities of the
nucleon.

</DOC>
<DOC>
<DOCNO> 85212 </DOCNO>
The Friedmann universe of dust by Regge Calculus: study of its ending


  We develop an evolution scheme, based on Sorkin algorithm, to evolve the most
complex regular tridimensional polytope, the 600-cell. This application has
been already studied before and all authors found a stop point for the
evolution of the spatial section. In our opinion a clear and satisfactory
meaning to this behaviour has not been given. In this paper we propose a reason
why the evolution of the 600-cell stops when its volume is still far from 0. We
find that the 600-cell meets a causality-breaking singularity of space-time. We
study the nature of this singularity by embedding the 600-cell into a
five-dimensional Lorentzian manifold. We fit 600-cell's evolution with a
continuos metric and study it as a solution of Einstein equations.

</DOC>
<DOC>
<DOCNO> 68621 </DOCNO>
The tensor reduction and master integrals of the two-loop massless


  The class of the two-loop massless crossed boxes, with light-like external
legs, is the final unresolved issue in the program of computing the scattering
amplitudes of 2 --> 2 massless particles at next-to-next-to-leading order.
  In this paper, we describe an algorithm for the tensor reduction of such
diagrams. After connecting tensor integrals to scalar ones with arbitrary
powers of propagators in higher dimensions, we derive recurrence relations from
integration-by-parts and Lorentz-invariance identities, that allow us to write
the scalar integrals as a combination of two master crossed boxes plus
simpler-topology diagrams.
  We derive the system of differential equations that the two master integrals
satisfy using two different methods, and we use one of these equations to
express the second master integral as a function of the first one, already
known in the literature. We then give the analytic expansion of the second
master integral as a function of epsilon=(4-D)/2, where D is the space-time
dimension, up to order O(epsilon^0).

</DOC>
<DOC>
<DOCNO> 69571 </DOCNO>
Neutrinos from Stellar Collapse: Comparison of the effects of three and


  We study the effect of non-vanishing masses and mixings among neutrino
flavours on the detection of neutrinos from stellar collapse by a water
Cerenkov detector. We consider a frame-work in which there are four neutrino
flavours, including a sterile neutrino, whose mass squared differences and
mixings are constrained by the present understanding of solar, atmospheric and
laboratory neutrino detection. We also include the effects of high density
matter within the supernova core. Unlike in the three flavour scenario, we find
that the number of events due to the dominant process involving
electron-antineutrinos changes dramatically for some allowed mixing parameters.
Furthermore, contributions from charged-current scattering off oxygen nuclei in
the detector can be considerably enhanced due to flavour mixing. We also
present a comparison between the two possible scenarios, namely, when only
three active neutrino flavours are present and when they are accompanied by a
fourth sterile neutrino.

</DOC>
<DOC>
<DOCNO> 120166 </DOCNO>
Lensing Degeneracies Revisited


  This paper shows that the mass-sheet degeneracy and other degeneracies in
lensing have simple geometrical interpretations: they are mostly rescalings of
the arrival-time surface. Different degeneracies appear in Local Group lensing
and in cosmological lensing, because in the former the absolute magnification
is measured but the image structure is not resolved, whereas in the latter the
reverse usually applies. The most dangerous of these is a combination we may
call the `mass-disk degeneracy' in multiply-imaging galaxy lenses, which may
lead to large systematic uncertainties in estimates of cosmological parameters
from these systems.

</DOC>
<DOC>
<DOCNO> 120790 </DOCNO>
High-Redshift Quasars Found in Sloan Digital Sky Survey Commissioning


  This is the fourth paper in a series aimed at finding high-redshift quasars
from five-color imaging data taken along the Celestial Equator by the SDSS.
during its commissioning phase. In this paper, we use the color-selected sample
of 39 luminous high-redshift quasars presented in Paper III to derive the
evolution of the quasar luminosity function over the range of 3.6<z<5.0, and
-27.5<M_1450<-25.5 (Omega=1, H_0=50 km s^-1 Mpc^-1). We use the selection
function derived in Paper III to correct for sample incompleteness. The
luminosity function is estimated using three different methods: (1) the 1/V_a
estimator; (2) a maximum likelihood solution, assuming that the density of
quasars depends exponentially on redshift and as a power law in luminosity and
(3) Lynden-Bell's non-parametric C^- estimator. All three methods give
consistent results. The luminous quasar density decreases by a factor of ~ 6
from z=3.5 to z=5.0, consistent with the decline seen from several previous
optical surveys at z<4.5. The luminosity function follows psi(L) ~ L^{-2.5} for
z~4 at the bright end, significantly flatter than the bright end luminosity
function psi(L) \propto L^{-3.5} found in previous studies for z<3, suggesting
that the shape of the quasar luminosity function evolves with redshift as well,
and that the quasar evolution from z=2 to 5 cannot be described as pure
luminosity evolution. Possible selection biases and the effect of dust
extinction on the redshift evolution of the quasar density are also discussed.

</DOC>
<DOC>
<DOCNO> 8175 </DOCNO>
Commensurate-Incommensurate Phase Transitions for Multichain Quantum


  The behavior in an external magnetic field is studied for a wide class of
multichain quantum spin models. It is shown that the magnetic field together
with the interchain couplings cause commensurate-incommensurate phase
transitions between the gapless phases in the ground state. The conformal limit
of these models is studied and it is shown that the low-lying excitations for
the incommensurate phases are not independent. A scenario for the transition
from one to two space dimensions for the integrable multichain models is
proposed. The similarities in the external field behavior for the quantum
multichain spin models and a wide class of quantum field theories are
discussed. The exponents for the gaps caused by relevant perturbations of the
models are calculated.

</DOC>
<DOC>
<DOCNO> 84882 </DOCNO>
Extended Thermodynamics to Einstein-Cartan Cosmology


  The thermodynamics is extented to spacetimes with spin-torsion
density.Impplications to Einstein-Cartan-de Sitter inflationary phases are
discussed.A relation between the spin-torsion density,entropy and temperature
is presented.A lower limit for the radius of the Universe may be obtained from
the spin-torsion density and the Planck lenght.

</DOC>
<DOC>
<DOCNO> 72000 </DOCNO>
On the massless "just-so" solution to the solar neutrino problem


  We study the effect of the non-resonant, vacuum oscillation-like neutrino
flavor conversion induced by non-standard flavor changing and non-universal
flavor diagonal neutrino interactions with electrons in the sun. We have found
an acceptable fit for the combined analysis for the solar experiments total
rates, the Super-Kamiokande (SK) energy spectrum and zenith angle dependence.
Phenomenological constraints on non-standard flavor changing and non-universal
flavor diagonal neutrino interactions are considered.

</DOC>
<DOC>
<DOCNO> 8496 </DOCNO>
Analysis of soft optical modes in hexagonal BaTiO3: transference of


  We have performed detailed first-principles calculations to determine the
eigenvectors of the zone-center modes of hexagonal BaTiO3 and shown that the
experimentally relevant low-energy modes (including the non-polar instability)
can be represented as suitable combinations of basic local polar distortions
associated with the instability of the cubic perovskite phase. The hexagonal
structure provides a testing ground for the analysis of the influence of the
stacking of TiO6 octahedra: the occurrence of relatively high-energy chains of
dipoles highlights the importance of local effects related to the coherent
hybridization enhancement between Ti and O ions. Our results provide simple
heuristic rules that could be useful for the analysis of related compounds.

</DOC>
<DOC>
<DOCNO> 122120 </DOCNO>
Completely dark galaxies: their existence, properties, and strategies


  There are a number of theoretical and observational hints that large numbers
of low-mass galaxies composed entirely of dark matter exist in the field. The
theoretical considerations follow from the prediction of cold dark matter
theory that there exist many low-mass galaxies for every massive one. The
observational considerations follow from the observed paucity of these low-mass
galaxies in the field but not in dense clusters of galaxies; this suggests that
the lack of small galaxies in the field is due to the inhibition of star
formation in the galaxies as opposed to the fact that their small dark matter
halos do not exist. In this work we outline the likely properties of low-mass
dark galaxies, and describe observational strategies for finding them, and
where in the sky to search. The results are presented as a function of the
global properties of dark matter, in particular the presence or absence of a
substantial baryonic dark matter component. If the dark matter is purely cold
and has a Navarro, Frenk and White density profile, directly detecting dark
galaxies will only be feasible with present technology if the galaxy has a
maximum velocity dispersion in excess of 70 km/s, in which case the dark
galaxies could strongly lens background objects. This is much higher than the
maximum velocity dispersions in most dwarf galaxies. If the dark matter in
galaxy halos has a baryonic component close to the cosmic ratio, the
possibility of directly detecting dark galaxies is much more realistic; the
optimal method of detection will depend on the nature of the dark matter. A
number of more indirect methods are also discussed.

</DOC>
<DOC>
<DOCNO> 99931 </DOCNO>
Spatial Structure in Low Dimensions for Diffusion Limited Two-Particle


  Consider the system of particles on ${\Bbb Z}^d$ where particles are of two
types, $A$ and $B$, and execute simple random walks in continuous time.
Particles do not interact with their own type, but when a type $A$ particle
meets a type $B$ particle, both disappear. Initially, particles are assumed to
be distributed according to homogeneous Poisson random fields, with equal
intensities for the two types. This system serves as a model for the chemical
reaction $A+B\to inert$. In [BrLe91a], the densities of the two types of
particles were shown to decay asymptotically like $1/t^{d/4}$ for $d<4$ and
$1/t$ for $d\geq 4$, as $t\to\infty$. This change in behavior from low to high
dimensions corresponds to a change in spatial structure. In $d<4$, particle
types segregate, with only one type present locally. After suitable rescaling,
the process converges to a limit, with density given by a Gaussian process. In
$d>4$, both particle types are, at large times, present locally in
concentrations not depending on the type, location or realization. In $d=4$,
both particle types are present locally, but with varying concentrations. Here,
we analyze this behavior in $d<4$; the behavior for $d\geq 4$ will be handled
in a future work [BrLe99].

</DOC>
<DOC>
<DOCNO> 69834 </DOCNO>
Unbroken versus broken mirror world: a tale of two vacua


  If the Lagrangian of nature respects parity invariance then there are two
distinct possibilities: either parity is unbroken by the vacuum or it is
spontaneously broken. We examine the two simplest phenomenologically consistent
gauge models which have unbroken and spontaneously broken parity symmetries,
respectively. These two models have a Lagrangian of the same form, but a
different parameter range is chosen in the Higgs potential. They both predict
the existence of dark matter and can explain the MACHO events. However, the
models predict quite different neutrino physics. Although both have light
mirror (effectively sterile) neutrinos, the ordinary-mirror neutrino mixing
angles are unobservably tiny in the broken parity case. The minimal broken
parity model therefore cannot simultaneously explain the solar, atmospheric and
LSND data. By contrast, the unbroken parity version can explain all of the
neutrino anomalies. Furthermore, we argue that the unbroken case provides the
most natural explanation of the neutrino physics anomalies (irrespective of
whether evidence from the LSND experiment is included) because of its
characteristic maximal mixing prediction.

</DOC>
<DOC>
<DOCNO> 85314 </DOCNO>
Multicolour Observations, Inhomogeneity & Evolution


  We propose a method of testing source evolution theories that is independent
of the effects of inhomogeneity, and thus complementary to other studies of
evolution. It is suitable for large scale sky surveys, and the new generation
of large telescopes.
 In an earlier paper it was shown that basic cosmological observations -
luminosity versus redshift, area distance versus redshift and number counts
versus redshift - cannot separate the effects of cosmic inhomogeneity, cosmic
evolution and source evolution. We here investigate multicolour observations,
and show that by comparing luminosity versus redshift in two or more colours,
contraints can be placed on source evolution even if unknown source evolution
is present, providing an important test of evolution theories that is
complementary to present methods. However, number counts in different colours
versus redshift are not useful in separating the effects of source evolution
and inhomogeneity.

</DOC>
<DOC>
<DOCNO> 100333 </DOCNO>
Heat asymptotics with spectral boundary conditions


  Let $P$ be an operator of Dirac type on a compact Riemannian manifold with
smooth boundary. We impose spectral boundary conditions and study the
asymptotics of the heat trace of the associated operator of Laplace type.

</DOC>
<DOC>
<DOCNO> 179022 </DOCNO>
Degeneracies when T=0 Two Body Matrix Elements are Set Equal to Zero and


  The effects of setting all T=0 two body interaction matrix elements equal to
a constant (or zero) in shell model calculations (designated as $<T=0>=0$) are
investigated. Despite the apparent severity of such a procedure, one gets
fairly reasonable spectra. We find that using $<T=0>=0$ in single j shell
calculations degeneracies appear e.g. the $I={1/2} ^{-}$ and ${13/2}^{-}$
states in $^{43}$Sc are at the same excitation energies; likewise the
I=$3_{2}^{+}$,$7_{2}^{+}$,9$^{+}_{1}$ and 10$^{+}_{1}$ states in $^{44}$Ti. The
above degeneracies involve the vanishing of certain 6j and 9j symbols. The
symmetry relations of Regge are used to explain why these vanishings are not
accidental. Thus for these states the actual deviation from degeneracy are good
indicators of the effects of the T=0 matrix elements. A further indicator of
the effects of the T=0 interaction in an even - even nucleus is to compare the
energies of states with odd angular momentum with those that are even.

</DOC>
<DOC>
<DOCNO> 11185 </DOCNO>
The Antiferromagnetic Band Structure of La2CuO4 Revisited


  Using the Becke-3-LYP functional, we have performed band structure
calculations on the high temperature superconductor parent compound, La2CuO4.
Under the restricted spin formalism (rho(alpha) equal to rho(beta)), the
R-B3LYP band structure agrees well with the standard LDA band structure. It is
metallic with a single Cu x2-y2/O p(sigma) band crossing the Fermi level. Under
the unrestricted spin formalism (rho(alpha) not equal to rho(beta)), the UB3LYP
band structure has a spin polarized antiferromagnetic solution with a band gap
of 2.0 eV, agreeing well with experiment. This state is 1.0 eV (per formula
unit) lower than that calculated from the R-B3LYP. The apparent high energy of
the spin restricted state is attributed to an overestimate of on-site Coulomb
repulsion which is corrected in the unrestricted spin calculations. The
stabilization of the total energy with spin polarization arises primarily from
the stabilization of the x2-y2 band, such that the character of the eigenstates
at the top of the valence band in the antiferromagnetic state becomes a strong
mixture of Cu x2-y2/O p(sigma) and Cu z2/O' p(z). Since the Hohenberg-Kohn
theorem requires the spin restricted and spin unrestricted calculations give
exactly the same ground state energy and total density for the exact
functionals, this large disparity in energy reflects the inadequacy of current
functionals for describing the cuprates. This calls into question the use of
band structures based on current restricted spin density functionals (including
LDA) as a basis for single band theories of superconductivity in these
materials.

</DOC>
<DOC>
<DOCNO> 118584 </DOCNO>
Discovery of Spatial and Spectral Structure in the X-Ray Emission from


  The Chandra X-ray Observatory observed the Crab Nebula and Pulsar during
orbital calibration. Zeroth-order images with the High-Energy Transmission
Grating (HETG) read-out by the Advanced CCD Imaging Spectrometer spectroscopy
array (ACIS-S) show a striking richness of x-ray structure, at a resolution
comparable to that of the best ground-based visible-light observations. The
HETG--ACIS-S images reveal, for the first time, an x-ray inner ring within the
x-ray torus, the suggestion of a hollow-tube structure for the torus, and x-ray
knots along the inner ring and (perhaps) along the inward extension of the
x-ray jet. Although complicated by instrumental effects and the brightness of
the Crab Nebula, the spectrometric analysis shows systematic variations of the
x-ray spectrum throughout the Nebula.

</DOC>
<DOC>
<DOCNO> 170097 </DOCNO>
Berry's phase in view of quantum estimation theory, and its intrinsic


  In this paper, it is pointed out that the Berry's phase is a good index of
degree of no-commutativity of the quantum statistical model. Intrinsic
relations between the `complex structure' of the Hilbert space and Berry's
phase is also discussed.

</DOC>
<DOC>
<DOCNO> 11875 </DOCNO>
Inelastic Collisions of Ultracold Polar Molecules


  The collisional stability of ultracold polar molecules in electrostatic traps
is considered. Rate constants for collisions that drive molecules from
weak-field-seeking to strong-field-seeking states are estimated using a simple
model. The rates are found to be quite large, of order 10^{-12} - 10^{-10}
cm^3/sec, and moreover to grow rapidly in an externally applied electric field.
It is argued that these results are generic for polar molecules, and that
therefore polar molecules should be trapped by other than electrostatic means.

</DOC>
<DOC>
<DOCNO> 70053 </DOCNO>
Charge diffusion constant in hot and dense hadronic matter - A


  We evaluate charge diffusion constant of dense and hot hadronic matter based
on the molecular dynamical method by using a hadronic collision generator which
describes nuclear collisions at energies 10 < E < 100 GeV/A and satisfies
detailed balance at low temperatures (T < 200 MeV). For the hot and dense
hadronic matter of the temperature range, 100 < T < 200 MeV and baryon number
density, 0.16 < nB < 0.32 fm^-3, charge diffusion constant D gradually
increases from 0.5 fm c to 2 fm c with temperature and is almost independent of
baryon number density. Based on the obtained diffusion constant we make simple
discussions on the diffusion of charge fluctuation in ultrarelativistic nuclear
collisions.

</DOC>
<DOC>
<DOCNO> 151733 </DOCNO>
On Marginal Deformations in Superstring Field Theory


  We use level truncated superstring field theory to obtain the effective
potential for the Wilson line marginal deformation parameter which corresponds
to the constant vacuum expectation value of the U(1) gauge field on the D-brane
in a particular direction. We present results for both the BPS and the non-BPS
D-brane. In the case of non-BPS D-brane the effective potential has branches
corresponding to the extrema of the tachyon potential. In the branch with
vanishing tachyon vev (M-branch), the effective potential becomes flatter as
the level of the approximation is increased. The branch which corresponds to
the stable vacuum after the tachyon has condensed (V-branch) exists only for a
finite range of values of marginal deformation parameter. We use our results to
find the mass of the gauge field in the stable tachyonic vacuum. We find this
mass to be of a non-zero value which seems to stabilize as the level
approximation is improved.

</DOC>
<DOC>
<DOCNO> 116301 </DOCNO>
Atomic data from the Iron Project.XLIII. Transition probabilities for Fe


  An extensive set of dipole-allowed, intercombination, and forbidden
transition probabilities for Fe V is presented. The Breit-Pauli R-matrix (BPRM)
method is used to calculate 1.46 x 10^6 oscillator strengths for the allowed
and intercombination E1 transitions among 3,865 fine-structure levels dominated
by configuration complexes with n <= 10 and l <= 9. These data are complemented
by an atomic structure configuration interaction (CI) calculation using the
SUPERSTRUCTURE program for 362 relativistic quadrupole (E2) and magnetic dipole
(M1) transitions among 65 low-lying levels dominated by the 3d^4 and 3d^ 4s
configurations. Procedures have been developed for the identification of the
large number of fine-structure levels and transitions obtained through the BPRM
calculations. The target ion Fe VI is represented by an eigenfunction expansion
of 19 fine-structure levels of 3d^3 and a set of correlation configurations. Fe
V bound levels are obtained with angular and spin symmetries SL\pi and J\pi of
the (e + Fe VI) system such that 2S+1 = 5,3,1, L <= 10, J <= 8 of even and odd
parities. The completeness of the calculated dataset is verified in terms of
all possible bound levels belonging to relevant LS terms and transitions in
correspondence with the LS terms. The fine-structure averaged relativistic
values are compared with previous Opacity Project LS coupling data and other
works. The 362 forbidden transition probabilities considerably extend the
available data for the E2 and M1 transtions, and are in good agreement with
those computed by Garstang for the 3d^4 transitions.

</DOC>
<DOC>
<DOCNO> 12709 </DOCNO>
Amino acid classes and the protein folding problem


  We present and implement a distance-based clustering of amino acids within
the framework of a statistically derived interaction matrix and show that the
resulting groups faithfully reproduce, for well-designed sequences,
thermodynamic stability in and kinetic accessibility to the native state. A
simple interpretation of the groups is obtained by eigenanalysis of the
interaction matrix.

</DOC>
<DOC>
<DOCNO> 119731 </DOCNO>
Mid-infrared diagnostics to distinguish AGNs from starbursts


  We present new mid-infrared (MIR) diagnostics to distinguish emission of
active galactic nuclei (AGN) from that originating in starburst regions. Our
method uses empirical spectroscopic criteria based on the fact that MIR
emission from star forming or active galaxies arises mostly from HII regions,
photo-dissociation regions (PDRs) and AGNs. The analysis of the strength of the
6.2micron Unidentified Infrared Band (UIB) and the MIR continuum shows that
UIBs are very faint or absent in regions harboring the intense and hard
radiation fields of AGNs and pure HII regions, where the UIB carriers could be
destroyed. The MIR signature of AGNs is the presence of an important continuum
in the 3-10micron band which originates from very hot dust heated by the
intense AGN radiation field. Using these two distinct spectral properties found
in our MIR templates, we build diagnostic diagrams which provide quantitative
estimates of the AGN, PDR and HII region contribution in a given MIR spectrum.
This new MIR classification can be used to reveal the presence of AGNs highly
obscured by large columns of dust.

</DOC>
<DOC>
<DOCNO> 69504 </DOCNO>
Nucleon resonances in omega photoproduction


  The role of the nucleon resonances ($N^*$) in $\omega$ photoproduction is
investigated by using the resonance parameters predicted by Capstick and
Roberts [Phys. Rev. D {\bf 46}, 2864 (1992); {\bf 49}, 4570 (1994)]. In
contrast with the previous investigations based on the ${SU}(6) \times {O}(3)$
limit of the constituent quark model, the employed $N^* \to \gamma N$ and $N^*
\to \omega N$ amplitudes include the configuration mixing effects due to the
residual quark-quark interactions. The contributions from the nucleon
resonances are found to be significant relative to the non-resonant amplitudes
in changing the differential cross sections at large scattering angles and
various spin observables. In particular, we suggest that a crucial test of our
predictions can be made by measuring the parity asymmetry and beam-target
double asymmetry at forward scattering angles.

</DOC>
<DOC>
<DOCNO> 71690 </DOCNO>
Analytic Methods in Nonperturbative QCD


  Recently developed analytic methods in the framework of the Field Correlator
Method are reviewed in this series of four lectures and results of calculations
are compared to lattice data and experiment. Recent lattice data demonstrating
the Casimir scaling of static quark interaction strongly support the FCM and
leave very little space for all other theoretical models, e.g. instanton
gas/liquid model. Results of calculations for mesons, baryons, quark-gluon
plasma and phase transition temperature demonstrate that new analytic methods
are a powerful tool of nonperturbative QCD along with lattice simulations.

</DOC>
<DOC>
<DOCNO> 7734 </DOCNO>
First and second order transition of frustrated Heisenberg spin systems


  Starting from the hypothesis of a second order transition we have studied
modifications of the original Heisenberg antiferromagnet on a stacked
triangular lattice (STA-model) by the Monte Carlo technique. The change is a
local constraint restricting the spins at the corners of selected triangles to
add up to zero without stopping them from moving freely (STAR-model). We have
studied also the closely related dihedral and trihedral models which can be
classified as Stiefel models. We have found indications of a first order
transition for all three modified models instead of a universal critical
behavior. This is in accordance with the renormalization group investigations
but disagrees with the Monte Carlo simulations of the original STA-model
favoring a new universality class. For the corresponding x-y antiferromagnet
studied before, the second order nature of the transition could also not be
confirmed.

</DOC>
<DOC>
<DOCNO> 118554 </DOCNO>
Accretion disc-stellar magnetosphere interaction: field line inflation


  We calculate the structure of a force-free magnetosphere which is assumed to
corotate with a central star and which interacts with an embedded
differentially rotating accretion disc. The magnetic and rotation axes are
aligned and the stellar field is assumed to be a dipole. We concentrate on the
case when the amount of field line twisting through the disc-magnetosphere
interaction is large and consider different outer boundary conditions. In
general the field line twisting produces field line inflation (eg. Bardou &
Heyvaerts 1996) and in some cases with large twisting many field lines can
become open. We calculate the spin-down torque acting between the star and the
disc and we find that it decreases significantly for cases with large field
line twisting. This suggests that the oscillating torques observed for some
accreting neutron stars could be due to the magnetosphere varying between
states with low and high field line inflation. Calculations of the spin
evolution of T Tauri stars may also have to be revised in light of the
significant effect that field line twisting has on the magnetic torque
resulting from star-disc interactions.

</DOC>
<DOC>
<DOCNO> 119768 </DOCNO>
Could the Unusual Optical Afterglow of GRB 000301c Arise from a


  Recent observations on the GRB 000301c afterglow show that three breaks
appear in the R-band light curve, and in particular the decay slope at late
times is as steep as -3.0. This unusual afterglow is clearly inconsistent with
the standard afterglow shock model. Here we propose a non-standard model for
the unusual R-band afterglow of GRB 000301c. In this model, an
ultra-relativistic shock in a dense medium ("dirty environment")rapidly evolved
to the non-relativistic phase in initial 1 day. During such a phase, the shock
happened to be caught up with by two energetic shells ejected from the central
engine at two different times, and the shock was refreshed, leading to two
flattenings of the light curve. After each interaction between the shock and
shell, the afterglow decayed as $\propto t^{-3.0}$ if the electron distribution
index of the shocked medium, $p\approx 3.4$, derived from the optical spectrum.
Therefore, this model can provide an excellent explanation for the flattening
and steepening features of the GRB 000301c optical afterglow light curve. We
further point out that the energy injection shells ejected from the central
engine at later times may be material shells (e.g., in the massive star
progenitor models related to black holes) or radiation shells (e.g., in the
millisecond pulsar progenitor models).

</DOC>
<DOC>
<DOCNO> 120655 </DOCNO>
Beat-Frequency Models of Kilohertz QPOs


  Kilohertz QPO sources are reasonably well-characterized observationally, but
many questions remain about the theoretical framework for these sources and the
consequent implications of the observations for disk physics, strong gravity,
and dense matter. We contrast the predictions and implications of the most
extensively studied class of kilohertz QPO models, the beat-frequency models,
with those of alternative classes of models. We also discuss the expected
impact of new observations of these sources with satellites such as Chandra,
XMM, and Constellation-X.

</DOC>
<DOC>
<DOCNO> 10192 </DOCNO>
Gap and subgap tunnelling in cuprates


  We describe strongly attractive carriers in cuprates in the framework of a
simple quasi-one dimensional Hamiltonian with a local attraction. In contrast
with the conventional BCS theory there are two energy scales, a temperature
independent incoherent gap $\Delta_p$ and a temperature dependent coherent gap
$\Delta_c (T)$ combining into one temperature dependent global gap
$\Delta=(\Delta_p^2 +\Delta_c^2)^{1/2}$. The temperature dependence of the gap
and single particle (Giaver) tunnelling spectra in cuprates are quantitatively
described. A framework for understanding of two distinct energy scales observed
in Giaver tunnelling and electron-hole reflection experiments is provided.

</DOC>
<DOC>
<DOCNO> 121458 </DOCNO>
Can differences in the nickel abundance in Chandrasekhar mass models


  The use of Type Ia supernovae as distance indicators relies on the
determination of their brightness. This is not constant, but it can be
calibrated using an observed relation between the brightness and the properties
of the optical light curve (decline rate, width, shape), which indicates that
brighter SNe have broader, slower light curves. However, the physical basis for
this relation is not yet fully understood. Among possible causes are different
masses of the progenitor white dwarfs or different opacities in
Chandrasekhar-mass explosions. We parametrise the Chandrasekhar-mass models
presented by Iwamoto et al (1999), which synthesize different amounts of Ni,
and compute bolometric light curves and spectra at various epochs. Since
opacity in SNe Ia is due mostly to spectral lines, it should depend on the mass
of Fe-peak elements synthesized in the explosion, and on the temperature in the
ejecta. Bolometric light curves computed using these prescriptions for the
optical opacity reproduce the relation between brightness and decline rate.
Furthermore, when spectra are calculated, the change in colour between maximum
and two weeks later allows the observed relation between M_B(Max) and
Dm_{15}(B) to be reproduced quite nicely. Spectra computed at various epochs
compare well with corresponding spectra of spectroscopically normal SNeIa
selected to cover a similar range of Dm_{15}(B) values.

</DOC>
<DOC>
<DOCNO> 72302 </DOCNO>
Inelastic diffractive scattering in nonperturbative QCD


  We examine diffractive proton-proton scattering p p -> p X and photo- and
electroproduction of \rho^0 mesons \gamma^(*) p -> \rho^0 X, where X denotes a
proton or a final state, into which the proton can go by diffractive
dissociation. Using a functional integral approach we derive the scattering
amplitudes, which are governed by the expectation values of light-like
Wegner-Wilson loops, which are then evaluated using the model of the stochastic
vacuum. For the proton, we assume a quark-diquark structure. From the
scattering amplitudes we calculate total and differential cross sections for
high centre of mass energy and small momentum transfer and compare with
experiments. Furthermore we calculate isovector form factors for the proton and
the pion within the same model.

</DOC>
<DOC>
<DOCNO> 102518 </DOCNO>
Alignment Correspondences


  We study correspondences of zero-dimensional subschemes of a smooth variety X
"aligned" in the same way in inside the appropriate product of Hilbert schemes.
We show that such correspondences have etale covering by other such
correspondences that are affine bundles over flag bundles on the tangent bundle
of X. Moreover, we show that for many such coverings, the closures of the
correspondences having these coverings vary so much that there is no
compactification of the covering dominating all of these closures.

</DOC>
<DOC>
<DOCNO> 151910 </DOCNO>
Some Issues in Non-commutative Tachyon Condensation


  Techniques of non-commutative field theories have proven to be useful in
describing D-branes as tachyonic solitons in open string theory. However, this
procedure also leads to unwanted degeneracy of solutions not present in the
spectrum of D-branes in string theories. In this paper we explore the
possibility that this apparent multiplicity of solutions is due to the wrong
choice of variables in describing the solutions, and that with the correct
choice of variables the unwanted degeneracy disappears.

</DOC>
<DOC>
<DOCNO> 100897 </DOCNO>
The theta divisor and the Casson-Walker invariant


  We use Heegaard decompositions and the theta divisor on a Riemannian surface
to define a three-manifold invariant for rational homology three-spheres. This
invariant is defined on the set of $Spin^c$ structures $$ {\hat \theta}\colon
Spin^c(Y)\longrightarrow Q. $$ In the first part of the paper, we give the
definition of the invariant (which builds on the theory developed in the
article, "The theta divisor and three-manifold invariants"). In the second
part, we establish a relationship between this invariant and the Casson-Walker
invariant.

</DOC>
<DOC>
<DOCNO> 118300 </DOCNO>
Extended X-ray emission from FRIIs and RL quasars


  We review the evidence that detectable fluxes of X-rays are produced by
inverse Compton scattering of nuclear photons with the relativistic electrons
in the radio lobes of strong FRII radio galaxies within the FRII-RL quasar
unification scheme. We report here on the possible detection of this effect in
two steep spectrum RL quasars. This may have important implications on the
physics and evolution of powerful radio galaxies.

</DOC>
<DOC>
<DOCNO> 120399 </DOCNO>
An Early-Time Infrared and Optical Study of the Type Ia Supernova 1998bu


  We present first-season infrared (IR) and optical photometry and spectroscopy
of the Type Ia Supernova 1998bu in M96. We also report optical polarimetry of
this event. SN1998bu is one of the closest type Ia Supernovae of modern times
and the distance of its host galaxy is well-determined. We find that SN1998bu
is both photometrically and spectroscopically normal. However, the extinction
to this event is unusually high, with Av=1.0 +/-0.11. We find that SN1998bu
peaked at an intrinsic Mv=-19.37 +/-0.23. Adopting a distance modulus of 30.25
(Tanvir et al. 1999) and using Phillips et al.'s (1999) relations for the
Hubble constant we obtain Ho=70.4 +/-4.3 km/s/Mpc. Combination of our IR
photometry with those of Jha et al. (1999) provides one of the most complete
early-phase IR light curves for a SN Ia published so far. In particular, SN
1998bu is the first normal SN Ia for which good pre-maximum (in the B band) IR
coverage has been obtained. It reveals that the J, H and K light curves peak
about 5 days earlier than the flux in the B-band curve.

</DOC>
<DOC>
<DOCNO> 10579 </DOCNO>
A toy model for molecular condensates in Bose gases


  The occurrence of a molecular Bose-Einstein condensate is studied for an
atomic system near a zero energy resonance of the binary scattering process,
with a large and positive scattering length. The interaction potential is
modeled by a pseudo-potential having one bound state. Using a variational
Gaussian ansatz for the $N$-body density operator, we discuss the thermodynamic
properties at low temperature and the relative stability of the system towards
the formation of an atomic Bose-Einstein condensate. We also derive an
approximate Gross-Pitaevskii equation for the molecular condensate leading to
the prediction of a Bogoliubov spectrum.

</DOC>
<DOC>
<DOCNO> 121163 </DOCNO>
Variable Iron K-alpha Lines in Seyfert 1 Galaxies


  We find that variability of the iron K-alpha line is common in Seyfert 1
galaxies. Using data from the ASCA archive for objects that have been observed
more than once during the mission, we study the time-averaged spectra from
individual observations, thereby probing variability on timescales that range
from days to years. Since the statistics of the data do not warrant searches
for line variability in terms of a complex physical model, we use a a simple
Gaussian to model the gross shape of the line, and then use the centroid
energy, intensity and equivalent width as robust indicators of changes in the
line profile. We find that ~70% of Seyfert 1s (ten out of fifteen) show
variability in at least one of these parameters: the centroid energy,
intensity, and equivalent width vary in six, four, and eight sources
respectively. Due to the low S/N, limited sampling and time averaging, we
consider these results to represent lower limits to the rate of incidence of
variability. In most cases changes in the line do not appear to track changes
in the continuum. In particular, we find no evidence for variability of the
line intensity in NGC 4151, suggesting an origin in a region larger than the
putative accretion disk, where most of the iron line has been thought to
originate. Mkn 279 is investigated on short timescales. The time-averaged
effective line energy is 6.5 keV in the galaxy rest frame. As the continuum
flux increases by 20% in a few hours, the Fe K line responds with the effective
line energy increasing by 0.22 keV (~10,500 km s^-1). Problems with the ASCA
and Rosat calibration that affect simultaneous spectral fits are discussed in
an appendix.

</DOC>
<DOC>
<DOCNO> 9995 </DOCNO>
Soft Modes, Resonances and Quantum Transport


  Effects of the propagation of particles, which have a finite life-time and an
according width in their mass spectrum, are discussed in the context of
transport description. First, the importance of coherence effects
(Landau-Pomeranchuk-Migdal effect) on production and absorption of field quanta
in non-equilibrium dense matter is considered. It is shown that classical
diffusion and Langevin results correspond to re-summation of certain
field-theory diagrams formulated in terms of full non-equilibrium Green's
functions. Then the general properties of broad resonances in dense and hot
systems are discussed in the framework of a self-consistent and conserving
Phi-derivable method of Baym at the examples of the rho-meson in hadronic
matter and the pion in dilute nuclear matter. Further we address the problem of
a transport description that properly accounts for the damping width of the
particles. The Phi-derivable method generalized to the real-time contour
provides a self-consistent and conserving kinetic scheme. We derive a
generalized expression for the non-equilibrium kinetic entropy flow, which
includes corrections from fluctuations and mass-width effects. In special cases
an H-theorem is proved. Memory effects in collision terms give contributions to
the kinetic entropy flow that in the Fermi-liquid case recover the famous
bosonic type T^3 ln T correction to the specific heat of liquid Helium-3. At
the example of the pion-condensate phase transition in dense nuclear matter we
demonstrate important part played by the width effects within the quantum
transport.

</DOC>
<DOC>
<DOCNO> 116386 </DOCNO>
Wavelet Cross-Correlation Analysis of Turbulent Mixing from


  The complex interactions existing between turbulence and mixing in a
bluff-body stabilised flame configuration is investigated by means of a wavelet
cross-correlation analysis on Large Eddy Simulations. The combined approach
allows to better point out typical features of unsteady turbulent flows with
mixing through the characterisation of the processes involved both in time and
scales. The wavelet cross-correlation analysis of the time signals of velocity
and mixture fraction fluctuations can be an an effective tool to study the
processes involved in turbulent mixing flows which are of great interest in
combustion problems.

</DOC>
<DOC>
<DOCNO> 99926 </DOCNO>
Mod 2 Seiberg-Witten invariants of homology tori


  We show that the mod 2 Seiberg-Witten invariant can be determined for a spin
manifold X which has the same homology groups as the 4-torus. The value depends
on the structure of the cohomology ring of X, and in particular on the 4-fold
cup product on H^1(X). We also consider some examples of homology tori.

</DOC>
<DOC>
<DOCNO> 9834 </DOCNO>
Escape-Rate Crossover between Quantum and Classical Regimes in Molecular


  We have studied numerically the quantum-classical crossover in the
escape-rate for an uniaxial spin system with an arbitrarily directed field.
Using the simple quantum transition-state theory, we have obtained the boundary
separating the first- and the second-order crossover and the escape-rate in the
presence of the transverse and longitudinal field. The results apply to the
molecular nanomagnet, ${\rm Mn_{12}}$.

</DOC>
<DOC>
<DOCNO> 150473 </DOCNO>
Instantons, Euclidean supersymmetry and Wick rotations


  We discuss the reality properties of the fermionic collective coordinates in
Euclidean space in an instanton background and construct hermitean actions for
N = 4 and N = 2 supersymmetric Euclidean Yang-Mills theories.

</DOC>
<DOC>
<DOCNO> 119355 </DOCNO>
Consequences of parton's saturation and string's percolation on the


  At high gluon or string densities, gluons' saturation or the strong
interaction among strings, either forming colour ropes or giving rise to
string's percolation, induces a strong suppression in the particle
multiplicities produced at high energy. This suppression implies important
modifications on cosmic ray shower development. In particular, it is shown that
it affects the depth of maximum, the elongation rate, and the behaviour of the
number of muons at energies around 10^{17}-10^{18} eV. The existing cosmic ray
data point out in the same direction.

</DOC>
<DOC>
<DOCNO> 7902 </DOCNO>
Supercooled Water: Dynamics, Structure and Thermodynamics


  The anomalous properties of water in the supercooled state are numerous and
well-known. Particularly striking are the strong changes in dynamic properties
that appear to display divergences at temperatures close to -- but beyond --
the lowest temperatures attainable either experimentally or in computer
simulations. Recent work on slow or glassy dynamics in water suggests analogies
with simple liquids not previously appreciated, and at the same time highlights
some aspects that remain peculiar to water. A comparison of the behavior of
water with normal liquids, with respect to its dynamic, thermodynamic and
structural changes in the supercooled regime is made by analyzing, via computer
simulations, the properties of local potential energy minima sampled by water
in supercooled temperatures and pressures.

</DOC>
<DOC>
<DOCNO> 116462 </DOCNO>
The ZEKE-effect in cold Rydberg gases


  Cold, dense Rydberg gases produced in a cold-atom trap are investigated using
spectroscopic methods and time-resolved electron counting. On the discrete
Rydberg resonances we observe large trap losses and long lasting electron
emission from the Rydberg gas (>30ms). Our observations are explained by
quasi-elastic l-mixing collisions between Rydberg atoms and slow electrons that
lead to the population of long-lived high-angular-momentum Rydberg states.
These atoms thermally ionize slowly and with large probabilities, leading to
the observed effects.

</DOC>
<DOC>
<DOCNO> 8223 </DOCNO>
Non-Newtonian shear viscosity in a dense system of hard disks


  In the present work a simple kinetic model based on the Enskog equation is
solved to get the rheological properties of a hard-disk fluid under shear far
from equilibrium, as functions of the density and shear rate. Comparison with
Monte Carlo simulations of the Enskog equation show excellent agreement.

</DOC>
<DOC>
<DOCNO> 40326 </DOCNO>
CLEO Results on Heavy Meson Mixing


  We discuss recent CLEO results on D0-D0bar and B0d-B0dbar mixing. The
principal results are that for the D0 system, allowing for CP violations, the
mixing amplitude x'<2.9% (95% C.L.), and for the B0d system,
chi=0.198+-0.013+-0.014. We make projections for future sensistivity to
D0-D0bar mixing, and to sin(2*beta+gamma).

</DOC>
<DOC>
<DOCNO> 70251 </DOCNO>
Signature neutrinos from ultrahigh-energy photons


  At high red shift, the temperature of cosmic microwave background is
sufficiently high for the ultrahigh-energy photons to pair-produce muons and
pions through interactions with the background photons. At the same time, the
radio background and magnetic fields are too weak to drain energy out of the
electromagnetic cascade before the muons and pions are produced. Decays of the
energetic muons and pions yield neutrinos with some distinctive spectral
properties that can be detected and can indicate the presence of
ultrahigh-energy photons at high red shift. The neutrino signature can help
identify the origin of cosmic rays beyond the Greisen-Zatsepin-Kuzmin cutoff.

</DOC>
<DOC>
<DOCNO> 169782 </DOCNO>
Entangled States of N Identical Particles


  We explore the connection between quantum entanglement and the exchange
symmetry of the states of N identical particles. Each particle has n-levels.
The N particles span the nN dimensional Hilbert space. We shall call the
general state of the particle as a qunit. The direct product of the N qunit
space is given a decomposition in terms of states with definite permutation
symmetry that are found to have a measure of entanglement which is related to
the representation of the permutation group. The maximally entangled states are
generated from the linear combinations of fully correlated but unentangled
states. The states of lower entanglement are generated from the manifold of
partially correlated states. The degree of exchange symmetry is found to be
related to a group theoretical measure of entanglement.
  Email: Jagdish_Rai@hotmail.com, jrai@iitk.ac.in Email: srai56@hotmail.com

</DOC>
<DOC>
<DOCNO> 121699 </DOCNO>
The Morphology of Extremely Red Objects


  We briefly discuss our survey of Extremely Red Objects (EROs) with HST/NICMOS
and deep ground-based images and summarize its results. We use the
high-resolution NICMOS images to sub-divide EROs into morphological classes,
tentatively arguing that about 60 % of EROs (18 out of 30) are early-type
galaxies. About 20 % (6 out of 30 objects) appear to be flattened disk systems.
Another 10 % (3 out of 30) have an irregular morphology. Thus, combining disk
and irregular systems, our data are compatible with 30 % of EROs being dusty
starbursts. A small fraction (3 out of 30) appear point-like even on the HST
images and could therefore be either compact high redshift galaxies or stars in
the Milky Way halo.

</DOC>
<DOC>
<DOCNO> 178566 </DOCNO>
Van der Waals Excluded Volume Model for Lorentz Contracted Rigid Spheres


  Conventional cluster and virial expansions are generalized to momentum
dependent inter-particle potentials. The model with Lorentz contracted hard
core potentials is considered, e.g. as hadron gas model. A Van der Waals-type
model with a temperature dependent excluded volume is derived. Lorentz
contraction effects at given temperature are stronger for light particles and
make their effective excluded volume smaller than that of heavy ones.

</DOC>
<DOC>
<DOCNO> 12736 </DOCNO>
X-Ray Diffuse Scattering Study on Ionic-Pair Displacement Correlations


  Ionic-pair equal-time displacement correlations in relaxor lead magnesium
niobate, $Pb(Mg_{1/3}Nb_{2/3})O_{3}$, have been investigated at room
temperature in terms of an x-ray diffuse scattering technique. Functions of the
distinct correlations have been determined quantitatively. The results show the
significantly strong rhombohedral-polar correlations regarding Pb-O, Mg/Nb-O,
and O-O' pairs. Their spatial distribution forms an ellipse or a sphere with
the radii of 30-80$\AA$. This observation of local structure in the system
proves precursory presence of the polar microregions in the paraelectric state
which leads to the dielectric dispersion.

</DOC>
<DOC>
<DOCNO> 11512 </DOCNO>
Surface tension of the isotropic-nematic interface


  We present the first calculations of the pressure tensor profile in the
vicinity of the planar interface between isotropic liquid and nematic liquid
crystal, using Onsager's density functional theory and computer simulation.
When the liquid crystal director is aligned parallel to the interface, the
situation of lowest free energy, there is a large tension on the nematic side
of the interface and a small compressive region on the isotropic side. By
contrast, for perpendicular alignment, the tension is on the isotropic side.
There is excellent agreement between theory and simulation both in the forms of
the pressure tensor profiles, and the values of the surface tension.

</DOC>
<DOC>
<DOCNO> 170761 </DOCNO>
Continued fraction solution to the Raman interaction of a trapped


  Raman interaction of a trapped ultracold ion with two traveling wave lasers
has been used extensively in the ion trap experiments. We solve this
interaction in the absence of the rotating wave approximation by a continued
fraction, without considering the restriction of the Lamb-Dicke limit and the
weak excitation regime. Some interesting characteristics of the ion-trap
system, particularly for the ion outside the weak excitation regime are found.
Finally, a comparison of our results with the solution under the rotating wave
approximation is made.

</DOC>
<DOC>
<DOCNO> 9410 </DOCNO>
Group projector generalization of dirac-heisenberg model


  The general form of the operators commuting with the ground representation
(appearing in many physical problems within single particle approximation) of
the group is found. With help of the modified group projector technique, this
result is applied to the system of identical particles with spin independent
interaction, to derive the Dirac-Heisenberg hamiltonian and its effective space
for arbitrary orbital occupation numbers and arbitrary spin. This gives
transparent insight into the physical contents of this hamiltonian, showing
that formal generalizations with spin greater than 1/2 involve nontrivial
additional physical assumptions.

</DOC>
<DOC>
<DOCNO> 71270 </DOCNO>
Dark Matter in Supergravity


  We consider neutralino-proton cross sections for halo dark matter neutralinos
within the framework of supergravity models with R-parity invariance for models
with universal soft breaking (mSUGRA) and models with nonuniversal soft
breaking. The analysis includes the necessary corrections to treat the large
tanbeta region (i.e. L-R mixing in the squark and slepton mass matrices, loop
corrections to the b and tau masses,etc) and includes all coannihilation
phenomena. For mSUGRA, dark matter detectors with current sensitivity are seen
to be probing the region where tanbeta>~25, Omega h^2 <0.1, m_{chi_1^0}~<90
GeV, and for the light Higgs, m_h~< 120 GeV. Nonuniversal models can have a
much larger cross section, and current detectors can probe part of the
parameter space where tan>~4. Minimum cross sections are generally greater than
10^{-9} pb to 10^{-10} pb for m_{1/2} <600 GeV (and hence accessible to planned
future detectors), with the exception of a region when mu <0 where for
m_{1/2}>~450 GeV, 4~< tanbeta~<20, the cross section drops to a minimum of
about 1\times10^{-12} pb at m_{1/2}=600 GeV, tan beta=~10. In this region, the
gluino and squarks lie above 1 TeV, but should still be accessible to the LHC.

</DOC>
<DOC>
<DOCNO> 11384 </DOCNO>
Opacity and Entanglement of Polymer Chains


  We argue that the mean crossing number of a random polymer configuration is
simply a measure of opacity, without being closely related to entanglement as
claimed by several authors. We present an easy way of estimating its asymptotic
behaviour numerically. These estimates agree for random walks (theta polymers),
self-avoiding walks, and for compact globules with analytic estimates giving
$\log N, a-b/N^{2\nu-1},$ and $N^{1/3}$, respectively, for the average number
of crossings per monomer in the limit $N\to \infty$. While the result for
compact globules agrees with a rigorous previous estimate, the result for SAWs
disagrees with previous numerical estimates.

</DOC>
<DOC>
<DOCNO> 71139 </DOCNO>
Sterile Neutrino and Accelerating Universe


  If all three neutrino oscillation data were to be confirmed in the near
future, it is probable that one might need a sterile neutrino, in addition to
the three active ones. This sterile neutrino, nu_S, would be very light with
mass m_{nu_S} less than or equal to 1 eV or even with m_{\nu_S} approximately
10^{-3} eV according to some scenarios. Why would it be so light? On another
front, recent cosmological observations and analyses appear to indicate that
the present universe is flat and accelerating, and that the present energy
density is dominated by a ``dark variety'', with rho_V approximately
(10^{-3}eV)^4. Is it a constant? Is there a link between these apparently
unrelated phenomena?

</DOC>
<DOC>
<DOCNO> 39761 </DOCNO>
Search for Charginos with a Small Mass Difference with the Lightest


  A search for charginos nearly mass-degenerate with the lightest
supersymmetric particle is performed using the 176 pb^-1 of data collected at
189 GeV in 1998 with the L3 detector. Mass differences between the chargino and
the lightest supersymmetric particle below 4 GeV are considered. The presence
of a high transverse momentum photon is required to single out the signal from
the photon-photon interaction background. No evidence for charginos is found
and upper limits on the cross section for chargino pair production are set. For
the first time, in the case of heavy scalar leptons, chargino mass limits are
obtained for any \tilde{\chi}^{+-}_1 - \tilde{\chi}^0_1 mass difference.

</DOC>
<DOC>
<DOCNO> 7702 </DOCNO>
Decay on several sorts of heterogeneous centers: Special monodisperse


  The situation of the metastable phase decay on the several types of
heterogeneous centers is considered. The method to spread the monodisperse
approximation on the situation of the strong unsymmetry is presented. The
simple analytical formulas for the main characteristics of the nucleation are
given. Three approximations for the supersaturation behavior are suggested and
the results of their application are analysed. This section is devoted to the
derivation of the general formulas.

</DOC>
<DOC>
<DOCNO> 102914 </DOCNO>
Indecomposable U_q(sl_n) modules for q^h = -1 and BRS intertwiners


  A class of indecomposable representations of U_q(sl_n) is considered for q an
even root of unity (q^h = -1) exhibiting a similar structure as (height h)
indecomposable lowest weight Kac-Moody modules associated with a chiral
conformal field theory. In particular, U_q(sl_n) counterparts of the
Bernard-Felder BRS operators are constructed for n=2,3. For n=2 a pair of dual
d_2(h) = h dimensional U_q(sl_2) modules gives rise to a 2h-dimensional
indecomposable representation including those studied earlier in the context of
tensor product expansions of irreducible representations. For n=3 the interplay
between the Poincare'-Birkhoff-Witt and (Lusztig) canonical bases is exploited
in the study of d_3(h) = h(h+1)(2h+1)/6 dimensional indecomposable modules and
of the corresponding intertwiners.

</DOC>
<DOC>
<DOCNO> 178818 </DOCNO>
The source of elliptic flow and initial conditions for hydrodynamical


  A model for energy, pressure and flow velocity distributions at the beginning
of relativistic heavy ion collisions is presented, which can be used as initial
condition for hydrodynamical calculations. The results show that QGP forms a
tilted disk, such that the direction of the largest pressure gradient stays in
the reaction plane, but deviates from both the beam and the usual transverse
flow directions. Such initial condition may lead to the creation of "antiflow"
or "third flow component".

</DOC>
<DOC>
<DOCNO> 100388 </DOCNO>
The anisotropic averaged Euler equations


  The purpose of this paper is to derive the anisotropic averaged Euler
equations and to study their geometric and analytic properties. These new
equations involve the evolution of a mean velocity field and an advected
symmetric tensor that captures the fluctuation effects. Besides the derivation
of these equations, the new results in the paper are smoothness properties of
the equations in material representation, which gives well-posedness of the
equations, and the derivation of a corrector to the macroscopic velocity field.
The numerical implementation and physical implications of this set of equations
will be explored in other publications.

</DOC>
<DOC>
<DOCNO> 152005 </DOCNO>
Anatomy of Two Holographic Renormalization Group Flows


  We derive and solve a subset of the fluctuation equations about two domain
wall solutions of D=5, N=8 gauged supergravity. One solution is dual to D=4,
N=4 SYM theory perturbed by an N=1, SO(3)-invariant mass term and the other to
a Coulomb branch deformation. In the first case we study all SO(3)-singlet
fields. These are assembled into bulk multiplets dual to the stress tensor
multiplet and to the N=1 chiral multiplets Tr Phi^2 and Tr W^2, the former
playing the role of anomaly multiplet. Each of these three multiplets has a
distinct spectrum of "glueball" states. This behavior is contrasted with the
Coulomb branch flow in which all fluctuations studied have a continuous
spectrum above a common mass gap, and spontaneous breaking of conformal
symmetry is driven by a bulk vector multiplet. R-symmetry is preserved in the
field theory, and correspondingly the bulk vector is dual to a linear anomaly
multiplet. Generic features of the fluctuation equations and solutions are
emphasized. For example, the transverse traceless modes of all fields in the
graviton multiplet can be expressed in terms of an auxiliary massless scalar,
and gauge fields associated with R-symmetry have a universal effective mass.

</DOC>
<DOC>
<DOCNO> 69711 </DOCNO>
Theoretical constraints on interaction amplitudes of light mesons


  We impose unitarity constraints on the S-wave isoscalar pion-pion amplitudes
extracted from the analysis of the pi- p ---> pi+ pi- n data which have been
measured by the CERN-Cracow-Munich collaboration on a transversely polarized
target at 17.2 GeV/c pi- momentum. Two "steep" solutions contain a narrow
S-wave f0(750) resonance under the rho(770) and exhibit a considerable
inelasticity eta which is in disagreement with the four pion production data
below the KKbar threshold. We impose eta= 1 for all data points and examine
four sets of solutions for the S-wave isoscalar phase-shifts. The "down-flat"
and "up-flat" solutions easily pass the eta=1 constraint but the remaining
"down-steep" and "up-steep" are eliminated. We conclude that the 17.2 GeV data
cannot be described by a relatively narrow f0(750).

</DOC>
<DOC>
<DOCNO> 152204 </DOCNO>
Vacuum Structure of Twisted Scalar Field Theories on M^{D-1} \otimes S^1


  We study scalar field theories on M^{D-1} \otimes S^1, which allow to impose
twisted boundary conditions for the S^1 direction, in detail and report several
interesting properties overlooked so far. One of characteristic features is the
appearance of critical radii of the circle S^1. A phase transition can occur at
the classical level or can be caused by quantum effects. Radiative corrections
can restore broken symmetries or can break symmetries for small radius. A
surprising feature is that the translational invariance for the S^1 direction
can spontaneously be broken. A particular class of coordinate-dependent vacuum
configurations is clarified and the O(N) \phi^4 model on M^{D-1}\otimes S^1 is
extensively studied, as an illustrative example.

</DOC>
<DOC>
<DOCNO> 99328 </DOCNO>
Holistic finite differences accurately model the dynamics of the


  We analyse the nonlinear Kuramoto-Sivashinsky equation to develop an accurate
finite difference approximation to its dynamics. The analysis is based upon
centre manifold theory so we are assured that the finite difference model
accurately models the dynamics and may be constructed systematically. The
theory is applied after dividing the physical domain into small elements by
introducing insulating internal boundaries which are later removed. The
Kuramoto-Sivashinsky equation is used as an example to show how holistic finite
differences may be applied to fourth order, nonlinear, spatio-temporal
dynamical systems. This novel centre manifold approach is holistic in the sense
that it treats the dynamical equations as a whole, not just as the sum of
separate terms.

</DOC>
<DOC>
<DOCNO> 102365 </DOCNO>
Some Comparisons for Gaussian Processes


  Extensions and variants are given for the well-known comparison principle for
Gaussian processes based on ordering by pairwise distance.

</DOC>
<DOC>
<DOCNO> 117433 </DOCNO>
Chemical Evolution of Damped Ly alpha galaxies: The [S/Zn] abundance


  Relative elemental abundances, and in particular the alpha/Fe ratio, are an
important diagnostic tool of the chemical evolution of damped Ly alpha systems
(DLAs). The S/Zn ratio is not affected by differential dust depletion and is an
excellent estimator of the alpha/Fe ratio. We report 6 new determinations of
sulphur abundance in DLAs at zabs greater than or equal to 2 with already known
zinc abundances. The combination with extant data from the literature provides
a measure of the S/Zn abundance ratio for a total of 11 high redshift DLA
systems. The observed [S/Zn] ratios do not show the characteristic [alpha/Fe]
enhancement observed in metal-poor stars of the Milky Way at comparable level
of metallicity ([Zn/H] ~ -1). The behaviour of DLAs data is consistent with a
general trend of decreasing [S/Zn] ratio with increasing metallicity [Zn/H].
This would be the first evidence of the expected decrease of the alpha/Fe ratio
in the course of chemical evolution of DLA systems. However, in contrast to
what observed in our Galaxy, the alpha/iron-peak ratio seems to attain solar
values when the metallicity is still low ([Zn/H] < -1) and to decrease below
solar values at higher metallicities. The behaviour of the alpha/Fe ratio
challenges the frequently adopted hypothesis that high redshift DLAs are
progenitors of spiral galaxies and favours instead an origin in galaxies
characterized by low star formation rates, in agreement with the results from
imaging studies of low redshift DLAs, where the candidate DLA galaxies show a
variety of morphological types including dwarfs and LSBs and only a minority of
spirals.

</DOC>
<DOC>
<DOCNO> 117664 </DOCNO>
Evolution of the Magnetic Field in Accreting Neutron Stars


  There has been sufficient observational indication suggesting a causal
connection between the binary history of neutron stars and the evolution of
their magnetic field. In particular, it is believed that the generation of the
low-field millisecond pulsars is a consequence of the processing of normal
high-field neutron stars in binary systems. We try to understand the mechanism
of field evolution in neutron stars that are members of binary systems with an
aim to understand the problem of millisecond pulsar generation. To this end we
have looked at four related problems : i. the effect of diamagnetic screening
on the final field of a neutron star accreting material from its binary
companion; ii. evolution of magnetic flux located in the crust of an accreting
neutron star; iii. application of the above-mentioned model to real systems and
a comparison with observations; iv. an investigation into the consequences of
magnetic flux being initially located in the core of the star and its
observational implications.

</DOC>
<DOC>
<DOCNO> 102688 </DOCNO>
Nonstandard Feynman path integral for the harmonic oscillator


  we will provide a rigorous computation for the harmonic oscillator Feynman
path integral. The computation will be done without having prior knowledge of
the classical path. We will see that properties of classical physics falls out
naturally from a purely quantum mechanical point of view. We will assume that
the reader is familiar with Nonstandard Analysis.

</DOC>
<DOC>
<DOCNO> 8110 </DOCNO>
Spin-1/2 transverse XX chain with a correlated disorder: dynamics of the


  We examine numerically the dynamics of zz correlations in the spin-1/2
isotropic XY chain with random intersite coupling and on-site transverse field
that depends linearly on the neighbouring couplings (correlated off-diagonal
and diagonal disorder). We discuss the changes in the frequency profiles of zz
dynamic structure factor caused by disorder.

</DOC>
<DOC>
<DOCNO> 84293 </DOCNO>
On the experimental foundations of the Maxwell equations


  We begin by reviewing the derivation of generalized Maxwell equations from an
operational definition of the electromagnetic field and the most basic notions
of what constitutes a dynamical field theory. These equations encompass the
familiar Maxwell equations as a special case but, in other cases, can predict
birefringence, charge non-conservation, wave damping and other effects that the
familiar Maxwell equations do not. It follows that observational constraints on
such effects can restrict the dynamics of the electromagnetic field to be very
like the familiar Maxwellian dynamics, thus, providing an empirical foundation
for the Maxwell equations. We discuss some specific observational results that
contribute to that foundation.

</DOC>
<DOC>
<DOCNO> 68448 </DOCNO>
Constraining CP Violating Phases of the MSSM


  Possible CP violation in supersymmetric (SUSY) extensions of the Standard
Model (SM) is discussed. The consequences of CP violating phases in the gaugino
masses, trilinear soft supersymmetry-breaking terms and the `mu' parameter are
explored. Utilizing the constraints on these parameters from electron and
neutron electric dipole moments, possible CP violating effects in B-physics are
shown. A set of measurements from the B-system which would overconstrain the
above CP violating phases is illustrated.

</DOC>
<DOC>
<DOCNO> 121931 </DOCNO>
Performance of the STACEE Atmospheric Cherenkov Telescope


  The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is located
at the National Solar Thermal Test Facility of Sandia National Laboratories in
Albuquerque, New Mexico, USA. The field of solar tracking mirrors (heliostats)
around a central receiver tower is used to direct Cherenkov light from
atmospheric showers onto secondary mirrors on the tower, which in turn image
the light onto cameras of photomultiplier tubes. The STACEE Collaboration has
previously reported a detection of the Crab Nebula with approximately 7
standard deviation significance, using 32 heliostats (STACEE-32). This result
demonstrates both the viability of the technique and the suitability of the
site. We are in the process of completing an upgrade to 48 heliostats
(STACEE-48) en route to an eventual configuration using 64 heliostats
(STACEE-64) in early 2001. In this paper, we summarize the results obtained on
the sensitivity of STACEE-32 and our expectations for STACEE-48 and STACEE-64.

</DOC>
<DOC>
<DOCNO> 14065 </DOCNO>
Fluctuations in galaxy counts: a new test for homogeneity versus


  Fractal properties are usually characterized by means of various statistical
tools which deal with spatial average quantities. Here we focus on the
determination of fluctuations around the average counts and we develop a test
for the study of galaxy distribution both in redshift and magnitude space.
Fluctuations in the counts of galaxies, in a fractal distribution, are of the
same order of the average number at all scales as a function of redshift and
magnitude. We point out that the study of these kind of fluctuations can be a
powerful test to understand the nature of galaxy clustering at very large
scales.

</DOC>
<DOC>
<DOCNO> 178825 </DOCNO>
Pygmy dipole resonances in relativistic random phase approximation


  The isovector dipole response in $^{208}$Pb is described in the framework of
a fully self-consistent relativistic random phase approximation. The NL3
parameter set for the effective mean-field Lagrangian with nonlinear meson
self-interaction terms, used in the present calculations, reproduces ground
state properties as well as the excitation energies of giant resonances in
nuclei. In addition to the isovector dipole resonance in $^{208}$Pb, the
present analysis predicts the occurrence of low-lying E1 peaks in the energy
region between 7 and 11 MeV. In particular, a collective state has been
identified whose dynamics correspond to that of a dipole pygmy resonance: the
vibration of the excess neutrons against the inert core composed of equal
number of protons and neutrons.

</DOC>
<DOC>
<DOCNO> 70565 </DOCNO>
Color-singlet direct J/\psi and \psi' production at Tevatron in the k_t


  Direct $J/\psi$ and $\psi'$ production rates at Tevatron are calculated in
the $k_t$-factorization approach within the color-singlet model. In this
approach, the production rates are enhanced by a factor of 20 compared to the
naive collinear parton model. However, the theoretical predictions are still
below the experimental data by at least one order of magnitude. This means that
to explain charmonium productions at Tevatron, we still need to call for the
contributions from color-octet channels or other production mechanisms.

</DOC>
<DOC>
<DOCNO> 118964 </DOCNO>
Deficiency of `Thin' Stellar Bars in Seyfert Host Galaxies


  Using all available major samples of Seyfert galaxies and their corresponding
control samples of closely matched non-active galaxies, we find that the bar
ellipticities (or axial ratios) in Seyfert galaxies are systematically
different from those in non-active galaxies. Overall, there is a deficiency of
bars with large ellipticities (i.e., `fat' or `weak' bars) in Seyferts,
compared to non-active galaxies. Accompanied with a large dispersion due to
small number statistics, this effect is strictly speaking at the `2sigma'
level. To obtain this result, the active galaxy samples of near-infrared
surface photometry were matched to those of normal galaxies in type, host
galaxy ellipticity, absolute magnitude, and, to some extent, in redshift. We
discuss possible theoretical explanations of this phenomenon within the
framework of galactic evolution, and, in particular, of radial gas
redistribution in barred galaxies. Our conclusions provide further evidence
that Seyfert hosts differ systematically from their non-active counterparts on
scales of a few kpc.

</DOC>
<DOC>
<DOCNO> 151013 </DOCNO>
On the quantum reflection factor for the sinh-Gordon model with general


  The one loop quantum corrections to the classical reflection factor of the
sinh-Gordon model are calculated partially for general boundary conditions. The
model is studied under boundary conditions which are compatible with
integrability, and in the framework of the conventional perturbation theory
generalized to the affine Toda field theory. It is found that the general form
of the related quantum corrections are hypergeometric functions.

</DOC>
<DOC>
<DOCNO> 8469 </DOCNO>
Thermodynamics of the Spin-1/2 Antiferromagnetic Uniform Heisenberg


  We present a new application of the traditional thermodynamic Bethe ansatz to
the spin-1/2 antiferromagnetic uniform Heisenberg chain and derive exact
nonlinear integral equations for just {\em two} functions describing the
elementary excitations. Using this approach the magnetic susceptibility $\chi$
and specific heat C versus temperature T are calculated to high accuracy for
$5\times10^{-25}\leq T/J\leq 5$. The $\chi(T)$ data agree very well at low T
with the asymptotically exact theoretical low-T prediction of S. Lukyanov,
Nucl. Phys. B {\bf 522}, 533 (1998). The unknown coefficients of the second and
third lowest-order logarithmic correction terms in Lukyanov's theory for C(T)
are estimated from the C(T) data.

</DOC>
<DOC>
<DOCNO> 8006 </DOCNO>
Spontaneous Breakdown of Translational Symmetry in Quantum Hall Systems:


  We report on results of systematic numerical studies of two-dimensional
electron gas systems subject to a perpendicular magnetic field, with a high
Landau level partially filled by electrons. Our results are strongly suggestive
of a breakdown of translational symmetry and the presence of crystalline order
in the ground state. This is in sharp contrast with the physics of the lowest
and first excited Landau levels, and in good qualitative agreement with earlier
Hartree-Fock studies. Experimental implications of our results are discussed.

</DOC>
<DOC>
<DOCNO> 8252 </DOCNO>
Propagation of Coulomb-correlated electron-hole pairs in semiconductors


  Local ultrafast optical excitation of electron-hole pairs in disordered
semiconductors provides the possibility to observe experimentally
interaction-assisted propagation of correlated quantum particles in a
disordered environment. In addition to the interaction driven delocalization
known for the conventional single-band TIP-(two-interacting-particles)-problem
the semiconductor model has a richer variety of physical parameters that give
rise to new features in the temporal dynamics. These include different masses,
correlated vs. anticorrelated disorder for the two particles, and dependence on
spectral position of excitation pulse.

</DOC>
<DOC>
<DOCNO> 151042 </DOCNO>
On the existence of the second Dirac operator in Riemannian space


  We describe a Riemannian space class where the second Dirac operator arises
and prove that the operator is always equivalent to a standard Dirac one. The
particle state in this gravitational field is degenerate to some extent and we
introduce an additional value in order to describe a particle state completely.
Some supersymmetry constructions are also discussed. As an example we study all
Riemannian spaces with a five-dimentional motion group and find all metrics for
which the second Dirac operator exists. On the basis of our discussed examples
we hypothesize about the number of second Dirac operators in Riemannian space.

</DOC>
<DOC>
<DOCNO> 84513 </DOCNO>
Gravitational Waves from the Dynamical Bar Instability in a Rapidly


  A rapidly rotating, axisymmetric star can be dynamically unstable to an m=2
"bar" mode that transforms the star from a disk shape to an elongated bar. The
fate of such a bar-shaped star is uncertain. Some previous numerical studies
indicate that the bar is short lived, lasting for only a few bar-rotation
periods, while other studies suggest that the bar is relatively long lived.
This paper contains the results of a numerical simulation of a rapidly rotating
gamma=5/3 fluid star. The simulation shows that the bar shape is long lived:
once the bar is established, the star retains this shape for more than 10
bar-rotation periods, through the end of the simulation. The results are
consistent with the conjecture that a star will retain its bar shape
indefinitely on a dynamical time scale, as long as its rotation rate exceeds
the threshold for secular bar instability. The results are described in terms
of a low density neutron star, but can be scaled to represent, for example, a
burned-out stellar core that is prevented from complete collapse by centrifugal
forces. Estimates for the gravitational-wave signal indicate that a dynamically
unstable neutron star in our galaxy can be detected easily by the first
generation of ground based gravitational-wave detectors. The signal for an
unstable neutron star in the Virgo cluster might be seen by the planned
advanced detectors. The Newtonian/quadrupole approximation is used throughout
this work.

</DOC>
<DOC>
<DOCNO> 83465 </DOCNO>
Algorithms for Rewriting Aggregate Queries Using Views


  Queries involving aggregation are typical in database applications. One of
the main ideas to optimize the execution of an aggregate query is to reuse
results of previously answered queries. This leads to the problem of rewriting
aggregate queries using views. Due to a lack of theory, algorithms for this
problem were rather ad-hoc. They were sound, but were not proven to be
complete.
  Recently we have given syntactic characterizations for the equivalence of
aggregate queries and applied them to decide when there exist rewritings.
However, these decision procedures do not lend themselves immediately to an
implementation. In this paper, we present practical algorithms for rewriting
queries with $\COUNT$ and $\SUM$. Our algorithms are sound. They are also
complete for important cases. Our techniques can be used to improve well-known
procedures for rewriting non-aggregate queries. These procedures can then be
adapted to obtain algorithms for rewriting queries with $\MIN$ and $\MAX$. The
algorithms presented are a basis for realizing optimizers that rewrite queries
using views.

</DOC>
<DOC>
<DOCNO> 11923 </DOCNO>
Orientation field model for chiral branching growth of bacterial


  We present a new reaction-diffusion model for chiral branching growth of
colonies of the bacteria Paenibacillus dendritiformis. In our model the
bacteria are represented by a density field with non-linear diffusion and a
complex scalar field which represents bacterial orientation. The orientation
field introduces anisotropy into the flux of bacteria, representing
self-propulsion along their long axes. The model can also reproduce
tip-splitting growth of other strains (shorter bacteria) of the same species.
The model can capture changes of small number of bacteria, thus it can be used
to study the open question of transitions between tip-splitting and chiral
dendritic growth.

</DOC>
<DOC>
<DOCNO> 150540 </DOCNO>
Recent Results on N=2 Superconformal Algebras


  In the last six years remarkable developments have taken place concerning the
representation theory of N=2 superconformal algebras. Here we present the
highlights of such developments.

</DOC>
<DOC>
<DOCNO> 117461 </DOCNO>
Nearby Optical Galaxies: Selection of the Sample and Identification of


  In this paper we describe the Nearby Optical Galaxy (NOG) sample, which is a
complete, distance-limited ($cz\leq$6000 km/s) and magnitude-limited
(B$\leq$14) sample of $\sim$7000 optical galaxies. The sample covers 2/3 (8.27
sr) of the sky ($|b|>20^{\circ}$) and appears to have a good completeness in
redshift (98%). We select the sample on the basis of homogenized corrected
total blue magnitudes in order to minimize systematic effects in galaxy
sampling.
  We identify the groups in this sample by means of both the hierarchical and
the percolation {\it friends of friends} methods. The resulting catalogs of
loose groups appear to be similar and are among the largest catalogs of groups
presently available. Most of the NOG galaxies ($\sim$60%) are found to be
members of galaxy pairs ($\sim$580 pairs for a total of $\sim$15% of objects)
or groups with at least three members ($\sim$500 groups for a total of
$\sim$45% of objects). About 40% of galaxies are left ungrouped (field
galaxies). We illustrate the main features of the NOG galaxy distribution.
Compared to previous optical and IRAS galaxy samples, the NOG provides a denser
sampling of the galaxy distribution in the nearby universe. Given its large sky
coverage, the identification of groups, and its high-density sampling, the NOG
is suited for the analysis of the galaxy density field of the nearby universe,
especially on small scales.

</DOC>
<DOC>
<DOCNO> 116478 </DOCNO>
Mechanism of Discordant Alternans in Spatially Homogenoeus Tissue


  Discordant alternans,the phenomenon of 2 separate cardiac tissue locations
exhibiting action potential duration (APD) alternans of opposite phase, appears
to be a potential mechanism for electrocardiographic T wave alternans, but its
initiation mechanism is unknown. We studied behavior of one- and two-
dimensional cardiac tissue spatially homogenous in all respects, including APD
restitution and conduction velocity restitution, using the Beeler Reuter ion
channel model. We found that discordant alternans was initiated when spatial
gradients of APD arose dynamically, such as from fixed rate pacing of a cable
end (sinus node scenario), or from fixed rate pacing at one site preceded by a
single excitation wavefront from another site (ectopic focus scenario). In the
sinus node scenario, conduction velocity restitution was necessary to initiate
discordant alternans. Alternating regimes of concordant and discordant
alternans arose along the length of the cable, with regimes delimited by nodes
of fixed APD. The number of observable nodes depended upon pacing rate and
tissue length. Differences in beat to beat conduction velocity values at steady
state were small. In the ectopic focus scenario, variable conduction velocity
was not required for induction of discrodant alternans. In both scenarios,
stability of node position was dependent upon electrotonic coupling. Other
mathematical models produced qualitatively similar results. We conclude that
spatial inhomogeneities of electrical restitution are not requiredd to produce
discordant alternans; rather, discordant alternans can arise dynamicaly from
interaction of APD and conduction veolocity resstitution with single site
pacing, or from APD restitution alone in two site pacing.

</DOC>
<DOC>
<DOCNO> 151801 </DOCNO>
On the Multi-Instanton Measure for Super Yang--Mills Theories


  In this paper we revisit the arguments that have led to the proposal of a
multi-instanton measure for supersymmetric Yang-Mills theories. We then recall
how the moduli space of gauge connections on $\real^4$ can be built from a
hyperk\"ahler quotient construction which we generalize to supermanifolds. The
measure we are looking for is given by the supermetric of the supermoduli space
thus introduced. To elucidate the construction we carry out explicit
computations in the case of N=2 supersymmetric Yang-Mills theories.

</DOC>
<DOC>
<DOCNO> 10879 </DOCNO>
From superconducting fluctuations to the bosonic limit in the response


  We investigate the density, current, and spin response functions above the
critical temperature for a system of three-dimensional fermions interacting via
an attractive short-range potential. In the strong-coupling (bosonic) limit of
this interaction, we identify the dominant diagrammatic contributions for a
``dilute'' system of composite bosons which form as bound-fermion pairs, and
compare them with the usual (Aslamazov-Larkin, Maki-Thompson, and
density-of-states) terms occurring in the theory of superconducting
fluctuations above the critical temperature for a clean system in the
weak-coupling limit. We show that, at the zeroth order in the diluteness
parameter for the composite bosons, the Aslamazov-Larkin term still represents
formally the dominant contribution to the density and current response
functions, while the Maki-Thompson and density-of-states terms are strongly
suppressed. Corrections to the Aslamazov-Larkin term are then considered at the
next order in the diluteness parameter for the composite bosons. The spin
response function is also examined, and it is found to be exponentially
suppressed in the bosonic limit only when appropriate sets of diagrams are
considered simultaneously.

</DOC>
<DOC>
<DOCNO> 83490 </DOCNO>
Random Shuffling to Reduce Disorder in Adaptive Sorting Scheme


  In this paper we present a random shuffling scheme to apply with adaptive
sorting algorithms. Adaptive sorting algorithms utilize the presortedness
present in a given sequence. We have probabilistically increased the amount of
presortedness present in a sequence by using a random shuffling technique that
requires little computation. Theoretical analysis suggests that the proposed
scheme can improve the performance of adaptive sorting. Experimental results
show that it significantly reduces the amount of disorder present in a given
sequence and improves the execution time of adaptive sorting algorithm as well.

</DOC>
<DOC>
<DOCNO> 100103 </DOCNO>
Noncommutative Riemann Surfaces


  We compactify M(atrix) theory on Riemann surfaces Sigma with genus g>1.
Following [1], we construct a projective unitary representation of pi_1(Sigma)
realized on L^2(H), with H the upper half-plane. As a first step we introduce a
suitably gauged sl_2(R) algebra. Then a uniquely determined gauge connection
provides the central extension which is a 2-cocycle of the 2nd Hochschild
cohomology group. Our construction is the double-scaling limit N\to\infty,
k\to-\infty of the representation considered in the Narasimhan-Seshadri
theorem, which represents the higher-genus analog of 't Hooft's clock and shift
matrices of QCD. The concept of a noncommutative Riemann surface Sigma_\theta
is introduced as a certain C^\star-algebra. Finally we investigate the Morita
equivalence.

</DOC>
<DOC>
<DOCNO> 71909 </DOCNO>
Levy Stable Law Description of the Intermittent Behavior in Pb+Pb


  The factorial moments (FM) of multiplicity distributions in one- and
two-dimensions are studied for Pb+Pb collisions at 158 AGeV/c. The results are
compared with FRITIOF, RQMD and VENUS predictions. In the relation between FM
and the number of partitions, $M$, obvious {\it positive} intermittence
exponents, $\phi_q$, are observed. The exponents, $\phi_q$, are compared with
the anomalous dimensions, $d_q$. Then they are expressed in terms of L\'evy
stable indices, $\mu$. Meanwhile the experimental data within the interval,
$2<\eta <6$, fulfills the requirements of the L\'evy stable region ($0 \le \mu
\le 2$), the results from the other intervals are away from this region. All
their corresponding indices have negative values.

</DOC>
<DOC>
<DOCNO> 84173 </DOCNO>
Fourth Order Theories Without Ghosts


  Using the Dirac constraint method we show that the pure fourth-order
Pais-Uhlenbeck oscillator model is free of observable negative norm states.
Even though such ghosts do appear when the fourth order theory is coupled to a
second order one, the limit in which the second order action is switched off is
found to be a highly singular one in which these states move off shell. Given
this result, construction of a fully unitary, renormalizable, gravitational
theory based on a purely fourth order action in 4 dimensions now appears
feasible.

</DOC>
<DOC>
<DOCNO> 119076 </DOCNO>
Spectroscopy and BVI photometry of the young open cluster NGC 6604


  BVI photometry (from South Africa Astron. Obs.), Echelle high resolution
spectroscopy and AFOSC integral field spectroscopy (from Asiago, Italy) of the
young open cluster NGC 6604 are presented. Age, distance, reddening,
membership, radial and rotational velocities are derived and discussed. An age
of 5 million years, a distance of 1.7 kpc and a reddening E(B-V)=1.02 are
found. The cluster radial velocity is in agreement with the Hron (1987) model
for the Galaxy disk rotation. Pre-ZAMS objects are not present down to M_V =
+1.5 mag.

</DOC>
<DOC>
<DOCNO> 72208 </DOCNO>
Exact solutions of Dyson-Schwinger equations for iterated one-loop


  The Hopf algebra of undecorated rooted trees has tamed the combinatorics of
perturbative contributions, to anomalous dimensions in Yukawa theory and scalar
$\phi^3$ theory, from all nestings and chainings of a primitive self-energy
subdivergence. Here we formulate the nonperturbative problems which these
resummations approximate. For Yukawa theory, at spacetime dimension $d=4$, we
obtain an integrodifferential Dyson-Schwinger equation and solve it
parametrically in terms of the complementary error function. For the scalar
theory, at $d=6$, the nonperturbative problem is more severe; we transform it
to a nonlinear fourth-order differential equation. After intensive use of
symbolic computation we find an algorithm that extends both perturbation series
to 500 loops in 7 minutes. Finally, we establish the propagator-coupling
duality underlying these achievements making use of the Hopf structure of
Feynman diagrams.

</DOC>
<DOC>
<DOCNO> 101553 </DOCNO>
ADE-bundles over rational surfaces, configuration of lines and rulings


  To each del Pezzo surface (resp. ruled surface, ruled surface with a
section), we describe a natural Lie algebra bundle of type E_n (resp. D_n, A_n)
over it. Using lines and rulings on any such surface, we describe various
representation bundles corresponding to fundamental representations of the
corresponding Lie algebra.
  When we specify a geometric structure on the surface to reduce the Lie
algebra to a smaller one, then the classical geometry of the configuration of
lines and rulings is encoded beautifully by the branching rules in Lie theory.
We discuss this relationship in details.
  When we degenerate the surface to a non-normal del Pezzo surface, we discover
that the configurations of lines and rulings are also governed by certain
branching rules.

</DOC>
<DOC>
<DOCNO> 169569 </DOCNO>
Generalized intelligent states and SU(1,1) and SU(2) squeezing


  A sufficient condition for a state |\psi> to minimize the
Robertson-Schr\"{o}dinger uncertainty relation for two observables A and B is
obtained which for A with no discrete spectrum is also a necessary one. Such
states, called generalized intelligent states (GIS), exhibit arbitrarily strong
squeezing (after Eberly) of A and B. Systems of GIS for the SU(1,1) and SU(2)
groups are constructed and discussed. It is shown that SU(1,1) GIS contain all
the Perelomov coherent states (CS) and the Barut and Girardello CS while the
Bloch CS are subset of SU(2) GIS.

</DOC>
<DOC>
<DOCNO> 84107 </DOCNO>
The collision and snapping of cosmic strings generating spherical


  The Penrose method for constructing spherical impulsive gravitational waves
is investigated in detail, including alternative spatial sections and an
arbitrary cosmological constant. The resulting waves include those that are
generated by a snapping cosmic string. The method is used to construct an
explicit exact solution of Einstein's equations describing the collision of two
nonaligned cosmic strings in a Minkowski background which snap at their point
of collision.

</DOC>
<DOC>
<DOCNO> 84214 </DOCNO>
Gravitational waves from cosmological compact binaries


  We consider gravitational waves emitted by various populations of compact
binaries at cosmological distances. We use population synthesis models to
characterize the properties of double neutron stars, double black holes and
double white dwarf binaries as well as white dwarf-neutron star, white
dwarf-black hole and black hole-neutron star systems. We use the
observationally determined cosmic star formation history to reconstruct the
redshift distribution of these sources and their merging rate evolution. The
gravitational signals emitted by each source during its early-inspiral phase
add randomly to produce a stochastic background in the low frequency band with
spectral strain amplitude between 10^{-18} Hz^{-1/2} and
 5 10^{-17} Hz^{-1/2} at frequencies in the interval [5 10^{-6}-5 10^{-5}] Hz.
The overall signal which, at frequencies above 10^{-4}Hz, is largely dominated
by double white dwarf systems, might be detectable with LISA in the frequency
range [1-10] mHz and acts like a confusion limited noise component which might
limit the LISA sensitivity at frequencies above 1 mHz.

</DOC>
<DOC>
<DOCNO> 80793 </DOCNO>
Phase diagram of four-dimensional dynamical triangulations with a


  We report on simulations of DT simplicial gravity for manifolds with the
topology of the 4-disk. We find evidence for four phases in a two-dimensional
parameter space. In two of these the boundary plays no dynamical role and the
geometries are equivalent to those observed earlier for the sphere $S^4$. In
another phase the boundary is maximal and the quantum geometry degenerates to a
one dimensional branched polymer. In contrast we provide evidence that the
fourth phase is effectively three-dimensional. We find discontinuous phase
transitions at all the phase boundaries.

</DOC>
<DOC>
<DOCNO> 68066 </DOCNO>
Higgs radiation off quarks in supersymmetric theories at e^+e^-


  Yukawa couplings between Higgs bosons and quarks in supersymmetric theories
can be measured in the processes e^+e^- -> Q Qbar + Higgs. We have determined
the cross sections of these processes in the minimal supersymmetric model
including the complete set of next-to-leading order QCD corrections for all
channels.

</DOC>
<DOC>
<DOCNO> 69642 </DOCNO>
Neutrino Mixing Schemes


  A revolution in our understanding of the neutrino sector is underway, driven
by observations that are interpreted in terms of changes in neutrino flavors as
they propagate. Since neutrino oscillations occur only if neutrinos are
massive, these phenomena indicate physics beyond the Standard Model. With the
present evidence for oscillations from atmospheric, solar and accelerator data,
we are already able to begin to make strong inferences about the mass spectrum
and mixings of neutrinos. Theoretical efforts to achieve a synthesis have
produced a variety of models with differing testable consequences. A
combination of particle physics, nuclear physics and astrophysics is needed for
a full determination of the fundamental properties of neutrinos. This article
reviews what has been achieved thus far and the future prospects for
understanding the nature of neutrino masses and mixing.

</DOC>
<DOC>
<DOCNO> 150948 </DOCNO>
String Scale in Noncommutative Yang-Mills


  We identify the effective string scale of noncommutative Yang-Mills theory
(NCYM) with the noncommutativity scale through its dual supergravity
description. We argue that Newton's force law may be obtained with 4
dimensional NCYM with maximal SUSY. It provides a nonperturbative
compactification mechanism of IIB matrix model. We can associate NCYM with the
von Neumann lattice by the bi-local representation. We argue that it is
superstring theory on the von Neumann lattice. We show that our identification
of its effective string scale is consistent with exact T-duality (Morita
equivalence) of NCYM.

</DOC>
<DOC>
<DOCNO> 13378 </DOCNO>
Upper bounds on the density of states of single Landau levels broadened


  We study a non-relativistic charged particle on the Euclidean plane R^2
subject to a perpendicular constant magnetic field and an R^2-homogeneous
random potential in the approximation that the corresponding random Landau
Hamiltonian on the Hilbert space L^2(R^2) is restricted to the eigenspace of a
single but arbitrary Landau level. For a wide class of Gaussian random
potentials we rigorously prove that the associated restricted integrated
density of states is absolutely continuous with respect to the Lebesgue
measure. We construct explicit upper bounds on the resulting derivative, the
restricted density of states. As a consequence, any given energy is seen to be
almost surely not an eigenvalue of the restricted random Landau Hamiltonian.

</DOC>
<DOC>
<DOCNO> 119879 </DOCNO>
VLBA observations of SiO masers: Arguments in favor of radiative pumping


  We have performed VLBA observations of the SiO v=1 and v=2 J=1-0 masers in
two AGB stars, TX Cam and IRC +10011. We confirm the ring-like spatial
distribution, previously found in several AGB objects, as well as the
tangential polarization pattern, already reported for TX Cam. Both properties,
that seem to be systematic in this kind of objects, are characteristic of
radiatively pumped SiO masers. On the contrary, we do not confirm the previous
report on the spatial coincidence between the J=1-0 v=1 and 2 masers, a result
that would have argued in favor of collisional pumping. We find that both lines
sometimes arise from nearby spots, typically separated by 1-2 mas, but are
rarely coincident. The discrepancy with previous results is explained by the
very high spatial resolution of our observations, ~ 0.5 mas, an order of
magnitude better than in the relevant previously published experiment.

</DOC>
<DOC>
<DOCNO> 120705 </DOCNO>
PMN J1838-3427: A new gravitationally lensed quasar


  We report the discovery of a new double-image quasar that was found during a
search for gravitational lenses in the southern sky. Radio source PMN
J1838-3427 is composed of two flat-spectrum components with separation 1", flux
density ratio 14:1 and matching spectral indices, in VLA and VLBA images.
Ground-based BRI images show the optical counterpart (total I=18.6) is also
double with the same separation and position angle as the radio components. An
HST/WFPC2 image reveals the lens galaxy. The optical flux ratio (27:1) is
higher than the radio value probably due to differential extinction of the
components by the lens galaxy. An optical spectrum of the bright component
contains quasar emission lines at z=2.78 and several absorption features,
including prominent Ly-alpha absorption. The lens galaxy redshift could not be
measured but is estimated to be z=0.36 +/- 0.08. The image configuration is
consistent with the simplest plausible models for the lens potential. The flat
radio spectrum and observed variability of PMN J1838-3427 suggest the time
delay between flux variations of the components is measurable, and could thus
provide an independent measurement of H_0.

</DOC>
<DOC>
<DOCNO> 119408 </DOCNO>
Extreme Type IIp Supernovae as Yardsticks for Cosmology


  Evolutionary effects with redshift of core collapse supernovae and their
application to cosmology have been studied based on an extensive grid of
stellar models between 13 and 25 Mo, and their light curves after the
explosion.
  With decreasing metallicity Z and increasing mass, progenitors tend to
explode as compact Blue Supergiants (BSG) and produce subluminous supernovae
which are about 1.5 mag. dimmer compared to 'normal' SNeII with Red Supergiant
(RSG) progenitors. Progenitors with small masses tend to explode as RSGs even
with low Z. The consequences are obvious for probing the chemical evolution.
  We identify 'extreme SNe IIp' supernovae as a rather homogeneous class which
may allow their use as standard candles for distance determination accurate
within 30 %. Due to their unique light curves, no spectra need to be taken for
their identification, and follow-up observations can be limited to a very small
dynamical range in brightness. This means that distance determination by
'extreme SNe IIp" are possible up to redshifts of about 3 using 8-meter class
telescopes. SIRTIF may push the limit by another magnitude.

</DOC>
<DOC>
<DOCNO> 101713 </DOCNO>
The Gibbs ensemble of a vortex filament


  We introduce a statistical ensemble for a single vortex filament of a three
dimensional incompressible fluid. The core of the vortex is modelled by a quite
generic stochastic process. We prove the existence of the partition function
for both positive and a limited range of negative temperatures.

</DOC>
<DOC>
<DOCNO> 119580 </DOCNO>
ALFA & 3D: integral field spectroscopy with adaptive optics


  One of the most important techniques for astrophysics with adaptive optics is
the ability to do spectroscopy at diffraction limited scales. The extreme
difficulty of positioning a faint target accurately on a very narrow slit can
be avoided by using an integral field unit, which provides the added benefit of
full spatial coverage. During 1998, working with ALFA and the 3D integral field
spectrometer, we demonstrated the validity of this technique by extracting and
distinguishing spectra from binary stars separated by only 0.26". The
combination of ALFA & 3D is also ideally suited to imaging distant galaxies or
the nuclei of nearby ones, as its field of view can be changed between
1.2"x1.2" and 4"x4", depending on the pixel scale chosen. In this contribution
we present new results both on galactic targets, namely young stellar objects,
as well as extra-galactic objects including a Seyfert and a starburst nucleus.

</DOC>
<DOC>
<DOCNO> 120264 </DOCNO>
The Frequency of Polarized Broad Emission Lines in Type 2 Seyfert


  We have discovered polarized broad emission lines in five type 2 Seyfert
galaxies (NGC 424, NGC 591, NGC 2273, NGC 3081, and NGC 4507), establishing
that these objects are type 1 Seyferts obscured by dense circumnuclear
material. The galaxies are part of a distance-limited sample of 31 Seyfert 2s,
for which spectropolarimetric observations are now complete. Combined with
published reports, our results indicate that at least 11 of the galaxies in
this sample, or > 35%, possess hidden broad-line regions. This represents the
first reliable estimate of the frequency of polarized broad emission lines in
type 2 Seyferts, which has important implications for the general applicability
of Seyfert unification models.

</DOC>
<DOC>
<DOCNO> 151606 </DOCNO>
Nonlinear Self-Duality and Supersymmetry


  We review self-duality of nonlinear electrodynamics and its extension to
several Abelian gauge fields coupled to scalars. We then describe self-duality
in supersymmetric models, both N = 1 and N = 2. The self-duality equations,
which have to be satisfied by the action of any self-dual system, are found and
solutions are discussed. One important example is the Born-Infeld action. We
explain why the N = 2 supersymmetric actions proposed so far are not the
correct world-volume actions for D3 branes in d = 6.

</DOC>
<DOC>
<DOCNO> 84538 </DOCNO>
Discrete spacetime: classical causality,prediction, retrodiction and the


  A mathematical definition of classical causality over discrete spacetime
dynamics is formulated. The approach is background free and permits a
definition of causality in a precise way whenever the spacetime dynamics
permits. It gives a natural meaning to the concepts of cosmic time, spacelike
hypersurfaces and timelike or lightlike flows without assuming the notion of a
background metric. The concepts of causal propagators and the speed of
causality are discussed. In this approach the concepts of spacetime and
dynamics are linked in an essential and inseparable whole, with no meaning to
either on its own.

</DOC>
<DOC>
<DOCNO> 8218 </DOCNO>
Intermittent implosion and pattern formation of trapped Bose-Einstein


  The collapsing dynamics of a trapped Bose-Einstein condensate (BEC) with
attractive interaction are revealed to exhibit two previously unknown
phenomena. During the collapse, BEC undergoes a series of rapid implosions that
occur {\it intermittently} within a very small region. When the sign of the
interaction is suddenly switched from repulsive to attractive, e.g., by the
Feshbach resonance, density fluctuations grow to form various patterns such as
a shell structure.

</DOC>
<DOC>
<DOCNO> 100832 </DOCNO>
Regularity of projections revisited


  The concept of regularity in the meta-topological setting of projections in
the double dual of a C*-algebra addresses the interrelations of a projection p
with its closure, for instance in the form that such projections act
identically, in norm, on elements of the C*-algebra. This concept has been
given new actuality with the recent plan of Peligrad and Zsido to find a
meaningful notion of Murray-von Neumann type equivalence among open
projections.
  Although automatic in the commutative case, it has been known since the late
sixties that regularity fails for many projections. The original
investigations, however, did not answer a question such as: "Are all open and
dense projections regular in A, when A is simple?"
  We report here that this and related questions have negative answers. In the
other direction, we supply positive results on regularity of large open
projections.

</DOC>
<DOC>
<DOCNO> 8221 </DOCNO>
Conductance fluctuations in diffusive rings: Berry phase effects and


  We study Berry phase effects on conductance properties of diffusive
mesoscopic conductors, which are caused by an electron spin moving through an
orientationally inhomogeneous magnetic field. Extending previous work, we start
with an exact, i.e. not assuming adiabaticity, calculation of the universal
conductance fluctuations in a diffusive ring within the weak localization
regime, based on a differential equation which we derive for the diffuson in
the presence of Zeeman coupling to a magnetic field texture. We calculate the
field strength required for adiabaticity and show that this strength is reduced
by the diffusive motion. We demonstrate that not only the phases but also the
amplitudes of the h/2e Aharonov-Bohm oscillations are strongly affected by the
Berry phase. In particular, we show that these amplitudes are completely
suppressed at certain magic tilt angles of the external fields, and thereby
provide a useful criterion for experimental searches. We also discuss Berry
phase-like effects resulting from spin-orbit interaction in diffusive
conductors and derive exact formulas for both magnetoconductance and
conductance fluctuations. We discuss the power spectra of the
magnetoconductance and the conductance fluctuations for inhomogeneous magnetic
fields and for spin-orbit interaction.

</DOC>
<DOC>
<DOCNO> 69006 </DOCNO>
Charge asymmetry due to the soft pion at high energy and its effect on


  Using the soft pion theorem in the inclusive reactions, we estimate the soft
pion contribution to the structure functions $F_2$ and $g_1$ in the nucleon,
and show that it is an indispensable part in these structure functions in the
small $x$ region. This contribution is asymmetric for the soft $\pi^+$ and
$\pi^-$ due to pole terms in the soft pion limit, hence it is a remnant of the
spontaneous chiral symmetry breakings. Then we show that the modified strange
sea quark where the soft pion contribution is added to the distribution
determined by the ansatz (strange-sea)=(up-sea + down-sea)/4 satisfies the mean
charge sum rule for the sea quarks.

</DOC>
<DOC>
<DOCNO> 83403 </DOCNO>
Torque Ripple Minimization in a Switched Reluctance Drive by Neuro-Fuzzy


  Simple power electronic drive circuit and fault tolerance of converter are
specific advantages of SRM drives, but excessive torque ripple has limited its
use to special applications. It is well known that controlling the current
shape adequately can minimize the torque ripple. This paper presents a new
method for shaping the motor currents to minimize the torque ripple, using a
neuro-fuzzy compensator. In the proposed method, a compensating signal is added
to the output of a PI controller, in a current-regulated speed control loop.
Numerical results are presented in this paper, with an analysis of the effects
of changing the form of the membership function of the neuro-fuzzy compensator.

</DOC>
<DOC>
<DOCNO> 80608 </DOCNO>
A Quantum Perfect Lattice Action for Monopoles and Strings


  A quantum perfect lattice action in four dimensions can be derived
analytically as a renormalized trajectory when we perform a block spin
transformation of monopole currents in a simple but non-trivial case of
quadratic monopole interactions. The spectrum of the lattice theory is
identical to that of the continuum theory. The perfect monopole action is
transformed exactly into a lattice action of a string model. A perfect operator
evaluating a static potential between electric charges is also derived
explicitly. If the monopole interactions are weak as in the case of infrared
SU(2) QCD, the string interactions become strong. The static potential and the
string tension is estimated analytically by the use of the strong coupling
expansion and the continuum rotational invariance is restored completely.

</DOC>
<DOC>
<DOCNO> 84578 </DOCNO>
Black Holes with Zero Mass


  We consider the spacetimes corresponding to static Global Monopoles with
interior boundaries corresponding to a Black Hole Horizon and analyze the
behavior of the appropriate ADM mass as a function of the horizon radius r_H.
We find that for small enough r_H, this mass is negative as in the case of the
regular global monopoles, but that for large enough r_H the mass becomes
positive encountering an intermediate value for which we have a Black Hole with
zero ADM mass.

</DOC>
<DOC>
<DOCNO> 152205 </DOCNO>
Relativistically covariant formulation of the canonical theory of


  A covariant description of the canonical theory for interacting classical
fields is developed on a space-like hypersurface. An identity invariant under
the canonical transformations is obtained. The identity follows a canonical
equation in which the interaction Hamiltonian density genarates a deformation
of the space-like hypersurface. The equation just corresponds to the
Yang-Feldman equation in the Heisenberg pictures in quantum field theory.

</DOC>
<DOC>
<DOCNO> 101185 </DOCNO>
Morse theory on graphs


  Let $\Gamma$ be a finite d-valent graph and G an n-dimensional torus. An
``action'' of G on $\Gamma$ is defined by a map, $\alpha$, which assigns to
each oriented edge e of $\Gamma$ a one-dimensional representation of G (or,
alternatively, a weight, $\alpha_e$, in the weight lattice of G). For the
assignment, $e \to \alpha_e$, to be a schematic description of a ``G-action'',
these weights have to satisfy certain compatibility conditions: the GKM axioms.
We attach to $(\Gamma, \alpha)$ an equivariant cohomology ring,
$H_G(\Gamma)=H(\Gamma,\alpha)$. By definition this ring contains the
equivariant cohomology ring of a point, $\SS(\fg^*) = H_G(pt)$, as a subring,
and in this paper we will use graphical versions of standard Morse theoretical
techniques to analyze the structure of $H_G(\Gamma)$ as an $\SS(\fg^*)$-module.

</DOC>
<DOC>
<DOCNO> 99938 </DOCNO>
Bochner-Kahler metrics


  A Kahler metric is said to be Bochner-Kahler if its Bochner curvature
vanishes. This is a nontrivial condition when the complex dimension of the
underlying manifold is at least 2. In this article it will be shown that, in a
certain well-defined sense, the space of Bochner-Kahler metrics in complex
dimension n has real dimension n+1 and a recipe for an explicit formula for any
Bochner-Kahler metric will be given.
  It is shown that any Bochner-Kahler metric in complex dimension n has local
(real) cohomogeneity at most n. The Bochner-Kahler metrics that can be
`analytically continued' to a complete metric, free of singularities, are
identified. In particular, it is shown that the only compact Bochner-Kahler
manifolds are the discrete quotients of the known symmetric examples. However,
there are compact Bochner-Kahler orbifolds that are not locally symmetric. In
fact, every weighted projective space carries a Bochner-Kahler metric.
  The fundamental technique is to construct a canonical infinitesimal torus
action on a Bochner-Kahler metric whose associated momentum mapping has the
orbits of its symmetry pseudo-groupoid as fibers.

</DOC>
<DOC>
<DOCNO> 122523 </DOCNO>
Optimising background-limited observing during bright-moon phases and


  For the majority of optical observing programs, the sky brightness provides
the fundamental limit to signal detection such that the scientific feasibility
is largely dictated by the moon phase. Since most observatories do not have the
resources to build expensive high-resolution or infrared instruments, they are
increasingly at a loss as to how to exploit bright time. We show that, with due
consideration of the field and moon position, it is possible to undertake `dark
time' observing programs under `bright time' conditions. Our recommendations
are particularly appropriate to all-sky survey programs.
  In certain instances, there are gains in observing efficiency with the use of
a polariser, which can significantly reduce the moonlight (or twilight)
sky-background flux relative to an extraterrestrial flux. These gains are
possible in background-limited cases because the sky background can be highly
polarised, due to scattering, around ninety degrees away from the moon (or
sun). To take advantage of this, only minor modifications to existing
instruments are needed.

</DOC>
<DOC>
<DOCNO> 70198 </DOCNO>
The `LEP paradox'


  Is there a Higgs? Where is it? Is supersymmetry there? Where is it? By
discussing these questions, we call attention to the `LEP paradox', which is
how we see the naturalness problem of the Fermi scale after a decade of
electroweak precision measurements, mostly done at LEP.

</DOC>
<DOC>
<DOCNO> 84698 </DOCNO>
Generalized Field Theoretical Approach to General Relativity and


  A new prescription to calculate the total energies and angular momenta of
asymptotically $(d+1)$-dimensional anti-de Sitter spacetimes is proposed. The
method is based on an extension of the field theoretical approach to General
Relativity to the case where there is an effective cosmological constant. A
$(d-1)$-form $\Omega$ is exhibited which, when integrated on asymptotic
$(d-1)$-dimensional boundary surfaces, yields the values of those conserved
quantities. The calculations are gauge independent once asymptotic conditions
are not violated . Total energies and angular momenta of some known solutions
in four and five dimensions are calculated agreeing with standard results.

</DOC>
<DOC>
<DOCNO> 170378 </DOCNO>
Infrared generation in low-dimensional semiconductor heterostructures


  A new scheme for infrared generation without population inversion between
subbands in quantum-well and quantum-dot lasers is presented and documented by
detailed calculations. The scheme is based on the simultaneous generation at
three frequencies: optical lasing at the two interband transitions which take
place simultaneously, in the same active region, and serve as the coherent
drive for the IR field. This mechanism for frequency down-conversion does not
rely upon any ad hoc assumptions of long-lived coherences in the semiconductor
active medium. And it should work efficiently at room temperature with
injection current pumping. For optimized waveguide and cavity parameters, the
intrinsic efficiency of the down-conversion process can reach the limiting
quantum value corresponding to one infrared photon per one optical photon. Due
to the parametric nature of IR generation, the proposed inversionless scheme is
especially promising for long-wavelength (far- infrared) operation.

</DOC>
<DOC>
<DOCNO> 69026 </DOCNO>
Superconducting Cosmic Strings


  These relics from the early universe could be the answer to many
astrophysical conundrums.

</DOC>
<DOC>
<DOCNO> 70833 </DOCNO>
Center vortices and colour confinement in lattice QCD


  We review lattice evidence showing that center-vortex condensation is a
serious candidate for the mechanism of colour confinement in quantum
chromodynamics.

</DOC>
<DOC>
<DOCNO> 121939 </DOCNO>
Disks at High Redshift: Interactions, Mergers, and Starbursts


  Do disk galaxies exist at redshifts much greater than unity, and how might
they look different from local disks? How does the morphological mix of
galaxies change with redshift? What can we learn from current observations
about the properties of high redshift galactic disks? I present theoretical
predictions based on semi-analytic hierarchical models, focussing on the role
played by interactions, mergers, and starbursts in determining the observable
properties of disk galaxies at high redshift, and discuss the interpretation of
high redshift observations of possible proto-disks (damped Lyman-$\alpha$
systems and Lyman-break galaxies) in light of these predictions.

</DOC>
<DOC>
<DOCNO> 152506 </DOCNO>
Gauge Invariant Correlators in Non-Commutative Gauge Theory


  Using perturbation theory, we explore the universal high momentum behavior of
correlation functions of gauge invariant operators in planar noncommutative
gauge theories. We find that the correlation functions are strongly enhanced
when pairs of momenta become antiparallel. In particular, there is a transition
from the previously noted exponential suppression of correlation functions at
high momenta to a more field theoretic behavior when the momenta of pairs of
operators antialign within a critical angle. Some of our calculations can be
extrapolated to strong coupling, and in particular we are able to reproduce
precisely the supergravity prediction for the behavior of two point functions,
including the coupling dependence.

</DOC>
<DOC>
<DOCNO> 7791 </DOCNO>
Density Fluctuations in Molten Lithium: Inelastic X-Ray Scattering Study


  New inelastic X-ray scattering experiments have been performed in liquid
lithium at two different temperatures: T=475 K (slightly above the melting
point) and 600 K. Taking advantage of the absence of any kinematical
restriction and incoherent contribution, and pushing the instrumental
resolution up to 1.5 meV, it was possible to perform an accurate investigation
of the dynamic structure factor S(Q,E) in the wavevector range from 1 to 110
nm^-1. For Q smaller than Q_m=25 nm^-1, the position of the main peak of the
static structure factor, a detailed analysis of the lineshapes shows that any
picture of the relaxation mechanisms based on a simple viscoelastic model must
be abandoned. All the spectral features can instead satisfactorily be accounted
for by including both fast and slow relaxation processes. The physical origin
of the slow relaxation is associated to the structural rearrangement, while the
local nature of the fast one is extensively discussed. At larger Q values a
gradual crossover from the strongly correlated to single particle dynamics
occurs, with an important weight provided by quantum effects.

</DOC>
<DOC>
<DOCNO> 120397 </DOCNO>
Looking for High Energy Peaked Blazars


  Blazars can be classified on the basis of their overall Spectral Energy
Distribution (SED). BL Lac objects are usually divided in LBL or HBL (Low or
High energy peaked BL Lacs), according to the peak frequency of the synchrotron
emission, if in the optical or UV-soft-X band respectively. FSRQs instead are
characterized by synchrotron peaks mainly at IR-optical frequencies, similarly
to LBLs. Here we report on recent BeppoSAX observations which are unveiling the
high energy branch of the range of synchrotron peak frequencies. Four new
"extreme" HBLs have been discovered, one of which (1ES 1426+428) peaks near or
above 100 keV, in a quiescent state.

</DOC>
<DOC>
<DOCNO> 119575 </DOCNO>
Discovery of 0.08 Hz QPO in the power spectrum of black hole candidate


  We found a strong QPO feature at 0.085+/-0.002 Hz in the power spectrum of
X-ray transient XTE J1118+480. The QPO was detected in PCA/RXTE data with an
amplitude close to 10% rms, and the width 0.034+/-0.006 Hz. The shape of the
power spectrum is typical for black hole candidates: almost flat at frequencies
lower than 0.03 Hz, roughly power law with slope ~1.2 from 0.03 to 1 Hz, with a
following steepening to ~1.6 at higher frequencies. The hard energy spectrum
detected up to ~150 keV and the absence of significant X-ray variability at the
high frequencies above 100 Hz strongly support the identification of XTE
J1118+480 as black hole transient.

</DOC>
<DOC>
<DOCNO> 101431 </DOCNO>
Stochastic Optimal Prediction with Application to Averaged Euler


  Optimal prediction (OP) methods compensate for a lack of resolution in the
numerical solution of complex problems through the use of an invariant measure
as a prior measure in the Bayesian sense. In first-order OP, unresolved
information is approximated by its conditional expectation with respect to the
invariant measure. In higher-order OP, unresolved information is approximated
by a stochastic estimator, leading to a system of random or stochastic
differential equations.
  We explain the ideas through a simple example, and then apply them to the
solution of Averaged Euler equations in two space dimensions.

</DOC>
<DOC>
<DOCNO> 85040 </DOCNO>
Darboux cosmological fluids in comoving time


  The barotropic indices and the corresponding FRW scale factors of the
so-called Darboux cosmological fluids are presented in the comoving time axis,
which is the natural one for the phenomenology related to the cosmological
data. Some useful comments on the features of the plots are included

</DOC>
<DOC>
<DOCNO> 118823 </DOCNO>
Entropy and equation of state for dense hot quark matter and its effect


  Dey et al. derived an equation of state (EOS) for matter in strange stars
(SS) with quark masses showing chiral symmetry restoration (CSM) and an
interquark potential which (i) has asymptotic freedom built into it, (ii) shows
confinement at zero density ($\rho_B = 0$) and deconfinement at high $\rho_B$.
This EOS gives a stable configuration for chargeless, $\be$-stable quark
matter. The SS derived from this EOS fits into the empirical mass -radius (M-R)
relations of some stars constraining the CSM parameters. In the present paper
we extend the calculation to include high temperatures upto T = 10 MeV \equiv
1.16 \times 10^{11}^oK where the quark gas is still degenerate and find that
the empirical M-R relation, derived from astrophysical data, is still
satisfied. The EOS is tabulated for T = 10 MeV.
  The entropy is calculated and matches onto that calculated from hadronic
models thus supporting the idea that the quark-hadron transition may be
continuous.

</DOC>
<DOC>
<DOCNO> 170184 </DOCNO>
The speed of quantum information and the preferred frame: analysis of


  The results of EPR experiments performed in Geneva are analyzed in the frame
of the cosmic microwave background radiation, generally considered as a good
candidate for playing the role of preferred frame. We set a lower bound for the
speed of quantum information in this frame at 1.5 x 10^4 c.

</DOC>
<DOC>
<DOCNO> 118892 </DOCNO>
Determining the reality of X-ray filaments


  A number of authors have reported filaments connecting bright structures in
high-resolution X-ray images, and in some cases these have been taken as
evidence for a physical connection between the structures, which might be
thought to provide support for a model with non-cosmological redshifts. In this
paper I point out two problems which are inherent in the interpretation of
smoothed photon-limited data of this kind, and develop some simple techniques
for the assessment of the reality of X-ray filaments, which can be applied to
either simply smoothed or adaptively smoothed data. To illustrate the
usefulness of these techniques, I apply them to archival ROSAT observations of
galaxies and quasars previously analysed by others. I show that several
reported filamentary structures connecting X-ray sources are not in fact
significantly detected.

</DOC>
<DOC>
<DOCNO> 101850 </DOCNO>
Tight contact structures with no symplectic fillings


  We exhibit tight contact structures on 3-manifolds that do not admit any
symplectic fillings.

</DOC>
<DOC>
<DOCNO> 178940 </DOCNO>
The Principle of Relativity and Modified Connection between the Mass of


  Following the basic idea expressed in [1], we assume that for any particle or
body with mass M its own time t depends on therelative change \frac{\Delta
M}{M} of that mass. Based on this assumption, one discusses possible existence
of a hypothetical particles and bodies with a velocity V>C

</DOC>
<DOC>
<DOCNO> 69871 </DOCNO>
PHEGAS: a phase-space generator for automatic cross-section computation


  A phase-space generation algorithm, capable to efficiently integrate the
squared amplitude of any scattering process, is presented. The algorithm has
been implemented in a Monte Carlo program, PHEGAS, which, using HELAC, a
helicity amplitude computational package,can be used for automatic
cross-section computation and event generation. Results for several scattering
processes with four, five and six particles in the final state are briefly
presented.

</DOC>
<DOC>
<DOCNO> 83111 </DOCNO>
The lexicographic closure as a revision process


  The connections between nonmonotonic reasoning and belief revision are
well-known. A central problem in the area of nonmonotonic reasoning is the
problem of default entailment, i.e., when should an item of default information
representing "if A is true then, normally, B is true" be said to follow from a
given set of items of such information. Many answers to this question have been
proposed but, surprisingly, virtually none have attempted any explicit
connection to belief revision. The aim of this paper is to give an example of
how such a connection can be made by showing how the lexicographic closure of a
set of defaults may be conceptualised as a process of iterated revision by sets
of sentences. Specifically we use the revision process of Nayak.

</DOC>
<DOC>
<DOCNO> 121411 </DOCNO>
Water and Dust Emission from W Hydrae


  We construct a self-consistent model for the wind around W Hya by solving the
coupled equations describing the hydrodynamics and dust radiative transfer
problems. The model matches simultaneously the observed continuum radiation and
wind velocity profile. The water line emission is calculated next using the
water abundance as the only free parameter, fitted from the ISO observations of
Neufeld et al. (1996) and Barlow et al. (1996). The gas temperature is
determined from a thermal balance calculation that includes water as one of its
main components. Our model successfully fits all the observed water lines,
resolving a major discrepancy between the modeling results of the two observing
teams. The mass loss rate is 2.3 x 10^{-6} M_solar yr^{-1}, the water abundance
is 1.0 x 10^{-4} and the ortho:para ratio is 1:1.3.

</DOC>
<DOC>
<DOCNO> 118319 </DOCNO>
IZ Photometry of L dwarfs and the implications for brown dwarf surevys


  The I-Z colour has been recently shown to be a good temperature indicator for
M dwarfs. We present the first IZ photometry of a small sample of L dwarfs
ranging in spectral type from L0.5V to L6.0V. We find that the I-Z colour is
not a good temperature indicator for objects between L1V and L5V, such objects
having colours that overlap with mid M dwarfs. We attribute this to the
reduction in the strength of the TiO and VO bands in the L dwarfs which are the
dominant opacity source in the I band for late M dwarfs. Beyond L5V, I-Z
appears to be a reasonable indicator. This has important implications for the
planning of optical surveys for cool objects in clusters and the field. For
example I-Z will cease to be a good method of discriminating brown dwarfs in
the Pleiades below around 0.04 Msolar, and at around 0.075 Msolar in the Hyades
and Praesepe.

</DOC>
<DOC>
<DOCNO> 85165 </DOCNO>
Solving the Initial Value Problem of two Black Holes


  We solve the elliptic equations associated with the Hamiltonian and momentum
constraints, corresponding to a system composed of two black holes with
arbitrary linear and angular momentum. These new solutions are based on a
Kerr-Schild spacetime slicing which provides more physically realistic
solutions than the initial data based on conformally flat metric/maximal
slicing methods. The singularity/inner boundary problems are circumvented by a
new technique that allows the use of an elliptic solver on a Cartesian grid
where no points are excised, simplifying enormously the numerical problem.

</DOC>
<DOC>
<DOCNO> 39628 </DOCNO>
Higgs Searches at LEP2 with the ALEPH Detector


  Data collected with the ALEPH detector at centre-of-mass energies between 130
and 189 GeV are used to search for Higgs bosons of the standard model and its
supersymmetric extensions. No evidence for a Higgs particle has been found in
256 pb^-1 of LEP2 data. Mass exclusion limits were set.

</DOC>
<DOC>
<DOCNO> 150653 </DOCNO>
Extended Complex Trigonometry in Relation to Integrable 2D-Quantum Field


  Multicomplex numbers of order n have an associated trigonometry (multisine
functions with (n-1) parameters) leading to a natural extension of the
sine-Gordon model. The parameters are constrained from the requirement of local
current conservation. In two dimensions for n < 6 known integrable models
(deformed Toda and non-linear sigma, pure affine Toda...) with dual
counterparts are obtained in this way from the multicomplex space MC itself and
from the natural embedding $\MC_n \subset \MMC_m, n < m$. For $ n \ge 6$ a
generic constraint on the space of parametersis obtained from current
conservation at first order in the interaction Lagragien.

</DOC>
<DOC>
<DOCNO> 8021 </DOCNO>
Learning structured data from unspecific reinforcement


  We show that a straightforward extension of a simple learning model based on
the Hebb rule, the previously introduced Association-Reinforcement-Hebb-Rule,
can cope with "delayed", unspecific reinforcement also in the case of
structured data and lead to perfect generalization.

</DOC>
<DOC>
<DOCNO> 85638 </DOCNO>
Integrability and Scheme-Independence of Even Dimensional Quantum


  We investigate how the integrability conditions for conformal anomalies
constrain the form of the effective action in even-dimensional quantum
geometry. We show that the effective action of four-dimensional quantum
geometry (4DQG) satisfying integrability has a manifestly diffeomorphism
invariant and regularization scheme-independent form. We then generalize the
arguments to six dimensions and propose a model of 6DQG. A hypothesized form of
the 6DQG effective action is given.

</DOC>
<DOC>
<DOCNO> 10043 </DOCNO>
Comment on: Critical behavior on the spin diluted 2D Ising model: A


  We point out that the "disorder potential" employed in the grand ensemble
approach is ill-defined in considerable generality.

</DOC>
<DOC>
<DOCNO> 118694 </DOCNO>
"Clocked" Bursts From GS 1826-238


  We report on the long term monitoring of the GINGA transient source GS
1826-238 performed with the BeppoSAX Wide Fiels Camera (WFC) instrument, during
four different observing campaigns covering October 1996 - September 1999. WFC
detection of type-I bursting activity from the source ruled out its proposed
black hole candidacy and clearly suggested the compact object related to GS
1826-238 to be a weakly magnetized neutron star. The analysis of the arrival
times of the observed 78 bursts lead to the discovery of a recurrence of ~5.75
hours with a spread of 38 minutes (FWHM) along more than 3 years monitoring
data (Ubertini et al., 1999). We performed a more detailed analysis of the
whole available data, and evidence of shortening of the recurrence time,
together with a drastic narrowing in the spread (down to a few minutes) was
observed on a one year time scale. Possible relation with the source X-ray
persistent emission is discussed.

</DOC>
<DOC>
<DOCNO> 101455 </DOCNO>
Perturbations of Weyl-Heisenberg frames


  We develop a usable perturbation theory for Weyl-Heisenberg frames. In
particular, we prove that if $(E_{mb}T_{na}g)_{m,n\inmathbb Z}$ is a WH-frame
and $h$ is a function which is close to $g$ in the Wiener Amalgam space norm,
then $(E_{mb}T_{na}h)_{m,n\in \mathbb Z}$ is also a WH-frame.

</DOC>
<DOC>
<DOCNO> 151976 </DOCNO>
Superconformal Algebras in Light-cone Gauge Quantization of String


  Motivated by superstring theories on $AdS_3$, we construct spacetime
superconformal algebras (SCAs) living on the $AdS_3$ boundary in terms of the
transversal physical degrees of freedom. The SCAs constructed are N=4 large,
middle algebras, and N=3 algebra, corresponding to superstring theories on
$AdS_3 \times S ^3 \times S^3 \times S ^1$, $AdS_3 \times S ^3 \times T ^4 $
and $AdS_3 \times (S^3\times S^3\times S^1)/Z_2$ backgrounds respectively.

</DOC>
<DOC>
<DOCNO> 123253 </DOCNO>
Global Magnetic Structures in Spiral Galaxies: Evidence for Dynamo


  Observational evidence for dynamo action in spiral galaxies is reviewed, and
the capabilities of various theories in explaining the basic features of
galactic magnetic fields are discussed. Mean-field dynamo models appear to be
unique in providing a coherent explanation of a wide variety of magnetic
features in spiral galaxies.
  Reliable modelling of global magnetic structures, such as the magnetic ring
in M31, requires detailed knowledge of the rotation curve, the magnitude and
radial profile of turbulent and noncircular systematic velocities, the scale
height of the warm ionized layer, the total gas density, the turbulent scale
and their variations with galactocentric radius. More detailed models involving
the effects of the spiral arms on magnetic field require the knowledge of the
arm-interarm contrasts in the above quantities.

</DOC>
<DOC>
<DOCNO> 8016 </DOCNO>
Submonolayer epitaxy with impurities


  The effect of impurities on epitaxial growth in the submonolayer regime is
studied using kinetic Monte Carlo simulations of a two-species solid-on-solid
growth model. Both species are mobile, and attractive interactions among
adatoms and between adatoms and impurities are incorporated. Impurities can be
codeposited with the growing material or predeposited prior to growth. The
activated exchange of impurities and adatoms is identified as the key kinetic
process in the formation of a growth morphology in which the impurities
decorate the island edges. The dependence of the island density on flux and
coverage is studied in detail. The impurities strongly increase the island
density without appreciably changing its power-law dependence on flux, apart
from a saturation of the flux dependence at high fluxes and low coverages. A
simple analytic theory taking into account only the dependence of the adatom
diffusion constant on impurity coverage is shown to provide semi-quantitative
agreement with many features observed in the simulations.

</DOC>
<DOC>
<DOCNO> 178864 </DOCNO>
Limits on the low-energy antinucleon annihilations from the Heisenberg


  Here a short synthesis is presented of the work, developed in the last two
years by the Brescia Collaboration, on the phenomenology of antinucleon-nucleon
and antinucleon-nucleus annihilation at small momenta (below 300 MeV/c in the
laboratory), with special stress on the role of general principles.

</DOC>
<DOC>
<DOCNO> 170566 </DOCNO>
Absolute frequency measurement of the In$^{+}$ clock transition with a


  The absolute frequency of the In$^{+}$ $5s^{2 1}S_{0}$ - $5s5p^{3}P_{0}$
clock transition at 237 nm was measured with an accuracy of 1.8 parts in
$10^{13}$. Using a phase-coherent frequency chain, we compared the $^{1}S_{0}$
- $^{3}P_{0}$ transition with a methane-stabilized He-Ne laser at 3.39 $\mu$m
which was calibrated against an atomic cesium fountain clock. A frequency gap
of 37 THz at the fourth harmonic of the He-Ne standard was bridged by a
frequency comb generated by a mode-locked femtosecond laser. The frequency of
the In$^{+}$ clock transition was found to be $1 267 402 452 899.92 (0.23)$
kHz, the accuracy being limited by the uncertainty of the He-Ne laser
reference. This represents an improvement in accuracy of more than 2 orders of
magnitude on previous measurements of the line and now stands as the most
accurate measurement of an optical transition in a single ion.

</DOC>
<DOC>
<DOCNO> 84401 </DOCNO>
On the strength of the Kerr singularity and cosmic censorship


  It has been suggested by Israel that the Kerr singularity cannot be strong in
the sense of Tipler, for it tends to cause repulsive effects. We show here
that, contrary to that suggestion, nearly all null geodesics reaching this
singularity do in fact terminate in Tipler's strong curvature singularity.
Implications of this result are discussed in the context of an earlier cosmic
censorship theorem which constraints the occurrence of Kerr-like naked
singularities in generic collapse situations.

</DOC>
<DOC>
<DOCNO> 12181 </DOCNO>
Multi-terminal Molecular Wire Systems: A Self-consistent Theory and


  We present a self-consistent method for the evaluation of the electronic
current flowing through a multi-terminal molecular wire. The method is based on
Buttiker- Landauer theory which relates the current to one-electron scattering
probabilities. The scattering problem is solved using a tight-binding form for
Schroedinger's equation that incorporates a self-consistent evaluation of the
electro-static potential in the region of the molecular wire. We apply the
method to a three-terminal molecular wire connected to metallic leads. The
molecular wire is a pi-conjugated carbon chain with thiol end groups,
self-assembled on the cleaved edge of a multilayer of alternating thin metal
and insulating films. The ends of the chain bond to two outer metal layers that
act as source and drain, and the chain bridges a third (inner) metal layer that
acts as a gate. We show that transistor action should occur in this device if
on the surface of the metal gate there are absorbed atoms that acquire charge
as the gate voltage is increased, thereby enhancing the interaction between the
gate and molecule and creating a strong potential barrier that hinders electron
flow along the molecular wire. We find that electronic solitons play an
important role in the response of this system to applied voltages.

</DOC>
<DOC>
<DOCNO> 11661 </DOCNO>
Controlled Transformation of Electrical, Magnetic and Optical Material


  Key circumstance of radical progress for technology of XXI century is the
development of a technique which provides controllable producing
three-dimensional patterns incorporating regions of nanometer sizes and
required physical and chemical properties. Our paper for the first time
proposes the method of purposeful direct transformation of the most important
substance physical properties, such as electrical, magnetic, optical and others
by controllable modification of solid state atomic constitution.
  The basis of the new technology is discovered by us effect of selective atom
removing out of thin di- and polyatomic films by beams of accelerated
particles. Potentials of that technique have been investigated and confirmed by
our numerous experiments. It has been shown, particularly, that selective atom
removing allows to transform in a controllable way insulators into metals,
non-magnetics into magnetics, to change radically optical features and some
other properties of materials.
  The opportunity to remove selectively atoms of a certain sort out of solid
state compounds is, as such, of great interest in creating technology
associated primarily with needs of nanoelectronics as well as many other
"nano-problems" of XXI century.

</DOC>
<DOC>
<DOCNO> 10682 </DOCNO>
Phase coherent transmission through interacting mesoscopic systems


  This is a review of the phase coherent transmission through interacting
mesoscopic conductors. As a paradigm we study the transmission amplitude and
the dephasing rate for electron transport through a quantum dot in the Coulomb
blockade regime. We summarize experimental and theoretical work devoted to the
phase of the transmission amplitude. It is shown that the evolution of the
transmission phase may be dominated by non-universal features in the short-time
dynamics of the quantum dot. The controlled dephasing in Coulomb coupled
conductors is investigated. Examples comprise a single or multiple quantum dots
in close vicinity to a quantum point contact. The current through the quantum
point contact "measures" the state of the dots and causes dephasing. The
dephasing rate is derived using widely different theoretical approaches. The
Coulomb coupling between mesoscopic conductors may prove useful for future work
on electron coherence and quantum computing.

</DOC>
<DOC>
<DOCNO> 69694 </DOCNO>
On impact parameter dependence of low-x structure functions


  We consider impact parameter dependence of the polarized and unpolarized
structure functions. Unitarity does not allow factorization of the structure
functions over the Bjorken x and the impact parameter b variables. On the basis
of the particular geometrical model approach we conclude that spin of
constituent quark may have a significant orbital angular momentum component
which can manifest itself through the peripherality of the spin dependent
structure functions.

</DOC>
<DOC>
<DOCNO> 10005 </DOCNO>
Connectivity of Growing Random Networks


  A solution for the time- and age-dependent connectivity distribution of a
growing random network is presented. The network is built by adding sites which
link to earlier sites with a probability A_k which depends on the number of
pre-existing links k to that site. For homogeneous connection kernels, A_k ~
k^gamma, different behaviors arise for gamma<1, gamma>1, and gamma=1. For
gamma<1, the number of sites with k links, N_k, varies as stretched
exponential. For gamma>1, a single site connects to nearly all other sites. In
the borderline case A_k ~ k, the power law N_k ~k^{-nu} is found, where the
exponent nu can be tuned to any value in the range 2<nu<infinity.

</DOC>
<DOC>
<DOCNO> 14129 </DOCNO>
Re-entrant behavior of relaxation time with viscosity at varying


  In order to understand the long known anomalies in the composition dependence
of diffusion and viscosity of binary mixtures, we introduce here two new models
and carry out extensive molecular dynamic simulations. In these models, the two
molecular species (A and B) have the same diameter and mass. In model I the
inter-species interaction is more attractive than that between the pure
components, while the reverse is true for model II. Simulations and also mode
coupling theory calculations reveal that the models can capture a wide variety
of behavior observed in experiments, most interesting among them are the
non-monotonic variation of diffusion and viscosity with the composition and the
re-entrant viscosity dependence of the relaxation time.

</DOC>
<DOC>
<DOCNO> 84681 </DOCNO>
Exact Solutions to the Motion of Two Charged Particles in Lineal Gravity


  We extend the canonical formalism for the motion of $N$-particles in lineal
gravity to include charges. Under suitable coordinate conditions and boundary
conditions the determining equation of the Hamiltonian (a kind of
transcendental equation) is derived from the matching conditions for the
dilaton field at the particles' position. The canonical equations of motion are
derived from this determining equation.
  For the equal mass case the canonical equations in terms of the proper time
can be exactly solved in terms of hyperbolic and/or trigonometric functions. In
electrodynamics with zero cosmological constant the trajectories for repulsive
charges exhibit not only bounded motion but also a countably infinite series of
unbounded motions for a fixed value of the total energy $H_{0}$, while for
attractive charges the trajectories are simply periodic. When the cosmological
constant $\Lambda$ is introduced, the motion for a given $\Lambda$ and $H_{0}$
is classified in terms of the charge-momentum diagram from which we can predict
what type of the motion is realized for a given charge.
  Since in this theory the charge of each particle appears in the form
$e_{1}e_{2}$ in the determining equation, the static balance condition in 1+1
dimensions turns out to be identical with the condition in Newtonian theory. We
generalize this condition to non-zero momenta, obtaining the first exact
solution to the static balance problem that does not obey the
Majumdar-Papapetrou condition.

</DOC>
<DOC>
<DOCNO> 118340 </DOCNO>
Extended Quintessence: imprints on the cosmic microwave background


  We describe the observable features of the recently proposed Extended
Quintessence scenarios on the Cosmic Microwave Background (CMB) anisotropy
spectra. In this class of models a scalar field $\phi$, assumed to provide most
of the cosmic energy density today, is non-minimally coupled to the Ricci
curvature scalar $R$. We implement the linear theory of cosmological
perturbations in scalar tensor gravitational theories to compute CMB
temperature and polarization spectra. All the interesting spectral features are
affected: on sub-degree angular scales, the acoustic peaks change both in
amplitude and position; on larger scales the low redshift dynamics enhances the
Integrated Sachs Wolfe effect. These results show how the future CMB
experiments could give information on the vacuum energy as well as on the
structure of the gravitational Lagrangian term.

</DOC>
<DOC>
<DOCNO> 152495 </DOCNO>
Consistency of the Hybrid Regularization with Higher Covariant


  We study the regularization and renormalization of the Yang-Mills theory in
the framework of the manifestly invariant formalism, which consists of a higher
covariant derivative with an infinitely many Pauli-Villars fields. Unphysical
logarithmic divergence, which is the problematic point on the Slavnov's method,
does not appear in our scheme, and the well-known vale of the renormalization
group functions are derived. The cancellation mechanism of the quadratic
divergence is also demonstrated by calculating the vacuum polarization tensor
of the order of $\Lambda^0$ and $\Lambda^{-4}$. These results are the evidence
that our method is valid for intrinsically divergent theories and is expected
to be available for the theory which contains the quantity depending on the
space-time dimensions, like supersymmetric gauge theories.

</DOC>
<DOC>
<DOCNO> 151050 </DOCNO>
Quasi exactly solvable matrix Schroedinger operators


  Two families of quasi exactly solvable 2*2 matrix Schroedinger operators are
constructed. The first one is based on a polynomial matrix potential and
depends on three parameters. The second is a one-parameter generalisation of
the scalar Lame equation. The relationship between these operators and QES
Hamiltonians already considered in the literature is pointed out.

</DOC>
<DOC>
<DOCNO> 69505 </DOCNO>
Axial Anomaly Effects in Pion and $Z^0$ Radiative Decays


  We discuss a connection between axial anomaly and polarized radiative
processes. By comparison with the corresponding unpolarized cases, we consider
some physical outputs for the $\pi^+$ and $Z^0$ polarized radiative decays. We
analyse in detail the pattern of mass singularity cancellation.

</DOC>
<DOC>
<DOCNO> 178435 </DOCNO>
Comment on Yuan et al


  The work of Yuan et al. (Phys. Rev. C 60 (1999) 045203) is being represented
as definitive regarding the non-existence of a particular nonstrange,
isoscalar, spin three dibaryon which has been proposed. We comment on this
paper and its relation to our work and that of others.

</DOC>
<DOC>
<DOCNO> 7721 </DOCNO>
"Quasi Universality classes" in 2D frustrated XY spin systems


  Classical XY spins on a two dimensional triangular lattice with
antiferromagnetic interactions are reconsidered. We find that the
Kosterlitz-Thouless transition associated to the U(1) symmetry appears at a
temperature 0.0020(2) below the Ising transition at 0.5122(1) associated to the
Z_2 symmetry. The Ising transition has critical exponents different from the
standard ones. Using extensive Monte Carlo simulations for equilibrium and
dynamical properties we show that the lack of universality observed in previous
studies is due to finite size corrections not taken account. Likewise the
Kosterlitz-Thouless transition has a critical exponent \eta\approx0.36 larger
than the corresponding standard value 0.25. Also the helicity jump at the
critical temperature is smaller than in the ferromagnetic case in disagreement
with theoretical predictions. We try using the concept of an "quasi
Universality class" to reconcile the standard critical behavior observable at
higher temperatures with the different quasi universal one close to the
critical region.

</DOC>
<DOC>
<DOCNO> 120849 </DOCNO>
Visualization of Large Multi-Dimensional Datasets


  Visualization techniques are well developed for many problem domains, but
these systems break down for datasets which are very large or multidimensional.
Techniques for data which is discrete rather than continuous are also less well
studied. Astronomy datasets like the Sloan Digital Sky Survey are very much in
this category. We propose the extension of information visualization techniques
to these very large record-oriented datasets. Specifically, we describe the
possible adaptation of the ``Visage'' information visualization tool to
terabyte astronomy datasets.

</DOC>
<DOC>
<DOCNO> 84627 </DOCNO>
Excitation of Kaluza-Klein modes of U(1) field by parametric resonance


  In this paper, based on the theory of parametric resonance, we propose a
cosmological criterion on ways of compactification: we rule out such a model of
compactification that there exists a Kaluza-Klein mode satisfying
$2m_{KK}=\omega_b$, where $m_{KK}$ is mass of the Kaluza-Klein mode and
$\omega_b$ is the frequency of oscillation of the radius of the compact
manifold on which extra dimensions are compactified. This is a restatement of
the criterion proposed previously [S. Mukohyama, Phys. Rev. {\bf D57}, 6191
(1998)]. As an example, we consider a model of compactification by a sphere and
investigate Kaluza-Klein modes of U(1) field. In this case the parametric
resonance is so mild that the sphere model is not ruled out.

</DOC>
<DOC>
<DOCNO> 122621 </DOCNO>
From the Galaxy to the Edge of the Universe: Plausible Sources of UHECRs


  The lack of a high energy cutoff in the cosmic ray spectrum together with an
apparently isotropic distribution of arrival directions for the highest energy
events have strongly constrained most models proposed for the generation of
these particles. An overview of the theoretical proposals are presented along
with their most general signatures. Future experimental tests of the different
proposals are discussed.

</DOC>
<DOC>
<DOCNO> 100244 </DOCNO>
Schrodinger Operators on Graphs


  This work is the direct continuation of the author's note published in
Russian Math Surveys 52 (1997), no 6. Discrete Schrodinger operators on graphs
and higher dimensional simplicial complexes are considered. A vector-valued
symplectic form on the space of solutions is consructed. This form, "Symplectic
Wronskian", takes value in the group of 1-dimensional cycles. This construction
has important applications for the Scattering Theory on graphs with tails.
Effective diagonalization of the real Fermionic quadratic form is presented in
the Appendix. This construction appeared first time in 1987 in the author's
paper dedicated to an analogue of Morse theory for vector fields (it was
published as an Appendix to the author's joint paper with M.Shubin, Soviet Math
Dokl 34 (1987) no 1).

</DOC>
<DOC>
<DOCNO> 150625 </DOCNO>
Witten-Veneziano Relation for the Schwinger Model


  The Witten-Veneziano relation between the topological susceptibility of pure
gauge theories without fermions and the main contribution of the complete
theory and the corresponding formula of Seiler and Stamatescu with the
so-called contact term are discussed for the Schwinger model on a circle. Using
the (Euclidean) path integral and the canonical (Hamiltonian) approaches at
finite temperatures we demonstrate that both formulae give the same result in
the limit of infinite volume and (or) zero temperature.

</DOC>
<DOC>
<DOCNO> 40051 </DOCNO>
Measurement of Rapidity Distribution for High Mass Drell-Yan ee Pairs at


  We report on the first measurement of the rapidity distribution dsigma/dy
over nearly the entire kinematic region of rapidity for e^+e^- pairs in the
Z-boson region of 66<M_{ee}<116 GeV/c^2 and at higher mass M_{ee}>116 GeV/c^2.
The data sample consists of 108 pb^{-1} of ppbar collisions at \sqrt{s}=1.8 TeV
taken by the Collider Detector at Fermilab during 1992--1995. The total cross
section in the $Z$-boson region is measured to be 252 +- 11 pb. The measured
total cross section and d\sigma/dy are compared with quantum chromodynamics
calculations in leading and higher orders.

</DOC>
<DOC>
<DOCNO> 12802 </DOCNO>
Magnetic field-induced Kondo effects in Coulomb blockade systems


  We review the peculiarities of transport through a quantum dot caused by the
spin transition in its ground state. Such transitions can be induced by a
magnetic field. Tunneling of electrons between the dot and leads mixes the
states belonging to the ground state manifold of the dot. Unlike the
conventional Kondo effect, this mixing, which occurs only at the
singlet-triplet transition point, involves both the orbital and spin degrees of
freedom of the electrons. We present theoretical and experimental results that
demonstrate the enhancement of the conductance through the dot at the
transition point.

</DOC>
<DOC>
<DOCNO> 100485 </DOCNO>
Nonresonance and global existence of prestressed nonlinear elastic waves


  The nonlinear hyperbolic system of pde's governing the evolution of the
deformation of isotropic hyperelastic materials is considered. In the absence
of boundaries and with an additional nonresonance or null condition, the system
has global smooth solutions starting close to a one-parameter family of
homogeneous dilations. The proof combines energy estimates with new decay
estimates for the linear problem.

</DOC>
<DOC>
<DOCNO> 100718 </DOCNO>
Deformation cohomology for Yetter-Drinfel'd modules and Hopf (bi)modules


  If A is a bialgebra over a field k and M, N are either left-right
Yetter-Drinfel'd modules or left-right Hopf modules over A, we construct
deformation cohomologies H^*(M,N) as total cohomologies of certain double
complexes Y(M,N) and C(M,N), respectively. In both cases, H^1(M,N) is
isomorphic to the group of equivalence classes of extensions of M by N in the
corresponding category. In the Yetter-Drinfel'd case, H^*(k,k) is just the
Gerstenhaber-Schack cohomology of the bialgebra A. If M, N are Hopf bimodules
we construct a natural subbicomplex of the above C(M,N), yielding a cohomology
theory for Hopf bimodules, similar to the one recently introduced by R.
Taillefer.

</DOC>
<DOC>
<DOCNO> 120821 </DOCNO>
Dynamical Mass Estimates for the Halo of M31 from Keck Spectroscopy


  The last few months have seen the measurements of the radial velocities of
all of the dwarf spheroidal companions to the Andromeda galaxy (M31) using the
spectrographs (HIRES and LRIS) on the Keck Telescope. This paper summarises the
data on the radial velocities and distances for all the companion galaxies and
presents new dynamical modelling to estimate the mass of extended halo of M31.
The best fit values for the total mass of M31 are between 7 and 10 x 10^{11}
solar masses, depending on the details of the modelling. The mass estimate is
accompanied by considerable uncertainty caused by the smallness of the dataset;
for example, the upper bound on the total mass is roughly 24 x 10^{11} solar
masses, while the lower bound is about 3 x 10^{11} solar masses. These values
are less than the most recent estimates of the most likely mass of the Milky
Way halo. Bearing in mind all the uncertainties, a fair conclusion is that the
M31 halo is roughly as massive as that of the Milky Way halo. There is no
dynamical evidence for the widely held belief that M31 is more massive -- it
may even be less massive.

</DOC>
<DOC>
<DOCNO> 12624 </DOCNO>
Equation of State in Quantum Chromodynamics


  The equation of state for quark-gluon plasma is obtained, being valid for
arbitrary values of the coupling parameter and of temperature. This equation is
constructed from perturbative expansions for free energy and for
renormalization function. Summation of asymptotic perturbative series is
accomplished by means of the self-similar approximation theory.

</DOC>
<DOC>
<DOCNO> 118709 </DOCNO>
16 x 25 Ge:Ga Detector Arrays for FIFI LS


  We are developing two-dimensional 16 x 25 pixel detector arrays of both
unstressed and stressed Ge:Ga photoconductive detectors for far-infrared
astronomy from SOFIA. The arrays, based on earlier 5 x 5 detector arrays used
on the KAO, will be for our new instrument, the Far Infrared Field Imaging Line
Spectrometer (FIFI LS). The unstressed Ge:Ga detector array will cover the
wavelength range from 40 to 120 microns, and the stressed Ge:Ga detector array
from 120 to 210 microns. The detector arrays will be operated with multiplexed
integrating amplifiers with cryogenic readout electronics located close to the
detector arrays. The design of the stressed detector array and results of
current measurements on several prototype 16 pixel linear arrays are reported.
They demonstrate the feasibility of the current concept. ***This paper does not
include Figures due to astro-ph size limitations. Please download entire file
at http://fifi-ls.mpe-garching.mpg.de/spie.det.ps.gz ***

</DOC>
<DOC>
<DOCNO> 170706 </DOCNO>
Supercoherent Quantum Bits


  Real quantum systems couple to their environment and lose their intrinsic
quantum nature through the process known as decoherence. Here we present a
method for minimizing decoherence by making it energetically unfavorable. We
present a Hamiltonian made up solely of two-body interactions between four
two-level systems (qubits) which has a two-fold degenerate ground state. This
degenerate ground state has the property that any decoherence process acting on
an individual physical qubit must supply energy from the bath to the system.
Quantum information can be encoded into the degeneracy of the ground state and
such supercoherent qubits will then be robust to local decoherence at low bath
temperatures. We show that this quantum information can be universally
manipulated using nearest neighbor interactions without destroying the
supercoherence. We demonstrate this approach with an analysis of supercoherence
in the context of a quantum dot proposal for a quantum computer.

</DOC>
<DOC>
<DOCNO> 13488 </DOCNO>
Modeling relaxation and jamming in granular media


  We introduce a stochastic microscopic model to investigate the jamming and
reorganization of grains induced by an object moving through a granular medium.
The model reproduces the experimentally observed periodic sawtooth fluctuations
in the jamming force and predicts the period and the power spectrum in terms of
the controllable physical parameters. It also predicts that the avalanche
sizes, defined as the number of displaced grains during a single advance of the
object, follow a power-law, $P(s)\sim s^{-\tau}$, where the exponent is
independent of the physical parameters.

</DOC>
<DOC>
<DOCNO> 69898 </DOCNO>
Improved Approximations for the Three-Loop Splitting Functions in QCD


  We update our approximate parametrizations of the three-loop splitting
functions for the evolution of unpolarized parton densities in perturbative
QCD. The new information taken into account is given by the additional Mellin
moments recently calculated by Retey and Vermaseren. The inclusion of these
constraints reduces the uncertainties of our approximations considerably and
extends their region of applicability by about one order of magnitude to lower
momentum fractions x .

</DOC>
<DOC>
<DOCNO> 9846 </DOCNO>
Chaotic, memory and cooling rate effects in spin glasses: Is the


  We investigate chaotic, memory and cooling rate effects in the three
dimensional Edwards-Anderson model by doing thermoremanent (TRM) and AC
susceptibility numerical experiments and making a detailed comparison with
laboratory experiments on spin glasses. In contrast to the experiments, the
Edwards-Anderson model does not show any trace of re-initialization processes
in temperature change experiments (TRM or AC). A detailed comparison with AC
relaxation experiments in the presence of DC magnetic field or coupling
distribution perturbations reveals that the absence of chaotic effects in the
Edwards-Anderson model is a consequence of the presence of strong cooling rate
effects. We discuss possible solutions to this discrepancy, in particular the
smallness of the time scales reached in numerical experiments, but we also
question the validity of the Edwards-Anderson model to reproduce the
experimental results.

</DOC>
<DOC>
<DOCNO> 120030 </DOCNO>
Rotation Curve Measurement using Cross-Correlation


  Longslit spectroscopy is entering an era of increased spatial and spectral
resolution and increased sample size. Improved instruments reveal complex
velocity structure that cannot be described with a one-dimensional rotation
curve, yet samples are too numerous to examine each galaxy in detail.
Therefore, one goal of rotation curve measurement techniques is to flag cases
in which the kinematic structure of the galaxy is more complex than a
single-valued curve.
  We examine cross-correlation as a technique that is easily automated and
works for low signal-to-noise spectra. We show that the technique yields
well-defined errors which increase when the simple spectral model (template) is
a poor match to the data, flagging those cases for later inspection.
  We compare the technique to the more traditional, parametric technique of
simultaneous emission line fitting. When the line profile at a single slit
position is non-Gaussian, the techniques disagree. For our model spectra with
two well-separated velocity components, assigned velocities from the two
techniques differ by up to ~52% of the velocity separation of the model
components. However, careful use of the error statistics for either technique
allows one to flag these non-Gaussian spectra.

</DOC>
<DOC>
<DOCNO> 69868 </DOCNO>
Phase transition in linear sigma model and disoriented chiral condensate


  We have investigated the phase transition and disoriented chiral condensate
domain formation in linear sigma model. Solving the equation of motion for the
sigma model fields in contact with a heat bath, we have shown that the fields
undergo phase transition above a certain critical temperature(T_c). It was also
shown that when the fields thermalised at temperature above T_c are cooled down
sufficiently rapidly, disoriented chiral condensate domains are formed quite
late in the evolution.

</DOC>
<DOC>
<DOCNO> 99717 </DOCNO>
Serre-Swan theorem for non-commutative C$^{*}$-algebras


  For a Hilbert C^*-module X over a C^*-algebra A, we construct a vector bundle
E_X associated with X.
 We represent X as a vector space \Gamma_X of some class of holomorphic
sections on E_X with the following properties: \Gamma_X is a Hilbert A-module
and \Gamma_X\cong X,
 E_X has a flat connection which defines the action of A on \Gamma_X,
 E_X has a hermitian metric H which induces the C^*-inner product of \Gamma_X.
  This section representation of modules is a kind of generalization of the
Serre-Swan theorem to non commutative C^*-algebras.
 We show that E_X is isomorphic to an associated bundle of an infinite
dimensional Hopf bundle with the structure group U(1).

</DOC>
<DOC>
<DOCNO> 13877 </DOCNO>
Quasiparticle lifetimes in the charged Bose gas and the cuprates


  The scattering cross section of a Coulomb potential screened by a charged
Bose gas (CBG) is calculated both above and below the Bose-Einstein
condensation temperature, using the variable phase method. In contrast with the
BCS superconductor, the screened scattering potential and quasiparticle
lifetime are found to be very different in the superconducting and normal
states. We apply the result to explain the appearence of a sharp peak in the
ARPES spectra in some cuprates below the superconducting transition.

</DOC>
<DOC>
<DOCNO> 67765 </DOCNO>
Instanton propagator in scalar model: exact expression and contribution


  The propagator in the instanton background in the -lambda phi^4 scalar model
in four dimensions is studied. Leading and sub-leading terms of its asymptotics
for large momenta and its on-shell double residue are calculated. These results
are applied to the analysis of the initial state and initial-final state
corrections and the calculation of the next-to-leading (propagator) correction
to the exponent of the cross section of multiparticle scattering processes.

</DOC>
<DOC>
<DOCNO> 71502 </DOCNO>
Neutrino Masses in SUSY Models


  In this talk we assume the conventional see-saw mechanism, and contruct a
hierarchical pattern of three active neutrinos with bi-maximal mixing. In order
to enforce the hierarchy we use the single right handed neutrino dominance
mechanism which is a very nice way to ensure a neutrino mass hierarchy in the
presence of large mixing angles. We show how this mechanism can be organised in
the framework of a U(1) family symmetry, then discuss a realistic
string-inspired model which includes such a symmetry.

</DOC>
<DOC>
<DOCNO> 117332 </DOCNO>
Superconducting Nb-film LC resonator


  Sputtered Nb thin-film LC resonators for low frequencies at 0.5 MHz have been
fabricated and tested in the temperature range 0.05--1 K in magnetic fields up
to 30 mT. Their Q value increases towards decreasing temperature as sqrt(T) and
reaches 10^3 at 0.05 K. As a function of magnetic field Q is unstable and
displays variations up to 50%, which are reproducible from one field sweep to
the next. These instabilities are attributed to dielectric losses in the plasma
deposited SiO_2 insulation layer, since the thin-film coil alone reaches a Q >
10^5 at 0.05 K.

</DOC>
<DOC>
<DOCNO> 70677 </DOCNO>
The Light-Cone Fock Representation in QCD


  The light-cone Fock-state representation of QCD encodes the properties of a
hadrons in terms of frame-independent wavefunctions, providing a systematic
framework for evaluating structure functions, exclusive hadronic matrix
elements, including time-like heavy hadron decay amplitudes, form factors, and
deeply virtual Compton scattering. A new type of jet production reaction,
"self-resolving diffractive interactions" can provide direct information on the
light-cone wavefunctions of hadrons in terms of their quark and gluon degrees
of freedom as well as the composition of nuclei in terms of their nucleon and
mesonic degrees of freedom. The relation of the intrinsic sea to the light-cone
wavefunctions is discussed. The decomposition of light-cone spin is illustrated
for the quantum fluctuations of an electron.

</DOC>
<DOC>
<DOCNO> 121228 </DOCNO>
The relation between extended radio and line emission for radio-loud


  We explore the relationship between the extended radio and line emission for
a radio-loud quasar sample including both core-dominated and lobe-dominated
quasars. A strong correlation is present between the extended radio and
broad-line emission. The core emission is also correlated with the broad-line
emission for core-dominated quasars in the sample. The statistic behaviour on
the core emission of lobe-dominated quasars is rather different from that of
core-dominated quasars. The extended radio luminosity is a good tracer for jet
power, while the core luminosity can only be a jet power tracer for
core-dominated quasars.

</DOC>
<DOC>
<DOCNO> 119354 </DOCNO>
The Sun's acoustic asphericity and magnetic fields in the solar


  The observed splittings of solar oscillation frequencies can be employed to
separate the effects of internal solar rotation and to estimate the
contribution from a large-scale magnetic field or any latitude-dependent
thermal perturbation inside the Sun. The surface distortion estimated from the
rotation rate in the solar interior is found to be in good agreement with the
observed oblateness at solar surface. After subtracting out the estimated
contribution from rotation, there is some residual signal in the even splitting
coefficients, which may be explained by a magnetic field of approximately 20 kG
strength located at a depth of 30000 km below the surface or an equivalent
aspherical thermal perturbation. An upper limit of 300 kG is derived for a
toroidal field near the base of the convection zone.

</DOC>
<DOC>
<DOCNO> 121721 </DOCNO>
On the Kinematics of GRB980425 and its association with SN1998bw


  In this paper I put forward a model in which GRB980425 is both associated
with SN1998bw and is also a standard canonical (long; ~seconds) gamma-ray
burst. Herein it is argued that if gamma-ray bursts are relativistic jets with
the fastest moving material at the core, then the range of observed jet
inclinations to the line-of-sight produces a range in the observed properties
of GRBs, i.e. the lag-luminosity relationship. In particular, if the jet
inclination is high enough, the observed emitter will move slowly enough to
render relativistic beaming ineffective, thus distinguishing the jet from
apparent isotropic emission. Thus we expect a break in the lag-luminosity
relationship. I propose that GRB980425 defines that break. The position of this
break gives important physical parameters such as the Lorentz factor
(\gamma_max ~ 1000), the jet opening angle (~1 degree), and thus the beaming
fraction (~10^-4). Estimates of burst rates are consistent with observation. If
correct, this model is evidence in favor of the collapsar mode as the
progenitor of cosmological, long gamma-ray bursts.

</DOC>
<DOC>
<DOCNO> 152420 </DOCNO>
Locally Anisotropic Supergravity and Gauge Gravity on Noncommutative


  We outline the the geometry of locally anisotropic (la) superspaces and
la-supergravity. The approach is backgrounded on the method of anholonomic
superframes with associated nonlinear connection structure. Following the
formalism of enveloping algebras and star product calculus we propose a model
of gauge la-gravity on noncommutative spaces. The corresponding Seiberg-Witten
maps are established which allow the definition of dynamics for a finite number
of gravitational gauge field components on noncommutative spaces.

</DOC>
<DOC>
<DOCNO> 11703 </DOCNO>
Magnetic field induced luminescence spectra in a quantum cascade laser


  We report on our study of the luminescence spectra of a quantum cascade laser
in the presence of an external magnetic field tilted from the direction
perpendicular to the electron plane. The effect of the tilted field is to allow
novel optical transitions because of the coupling of intersubband-cyclotron
energies. We find that by tuning the applied field, one can get optical
transitions at different energies that are as sharp as the zero-field
transitions.

</DOC>
<DOC>
<DOCNO> 120630 </DOCNO>
The environments and ages of extragalactic radio sources inferred from


  A 3-dimensional model of the synchrotron emissivity of the cocoons of
powerful extragalactic radio sources of type FRII is constructed. Bulk backflow
and energy losses of the relativistic electrons, radiative and adiabatic, are
self-consistently taken into account. Thus the model is an extension of
spectral aging methods including the underlying source dynamics into the age
estimates. The discrepancies between spectral ages and dynamical ages arising
from earlier methods are resolved. It is also shown that diffusion of
relativistic particles within the cocoon is unlikely to significantly change
the particle spectrum and thus the emitted radio spectrum. Projection along the
line of sight yields 1 or 2-dimensional surface brightness distributions which
can be compared with observations. From the model parameters constraints on the
source age, the density of the source environment and the angle to the line of
sight can be derived. Application of the method to Cygnus A, 3C 219 and 3C 215
show that the method provides robust estimates for the model parameters for
sources with comparatively regularly shaped radio lobes. The resolution of the
radio maps required is only moderate. Within the large uncertainties for the
orientation angle, the three example sources are found to be consistent with
orientation-based unification schemes of radio-loud AGN. In the case of Cygnus
A the gas density of the environment is found to agree with independent X-ray
measurements. For 3C 219 and 3C 215 the densities derived from the model are
apparently too low. It is suggested that these discrepancies are caused by
overestimates of slope and core radius of $\beta$-models for the gas density
distribution from X-ray observations for clusters hosting powerful radio
sources.

</DOC>
<DOC>
<DOCNO> 11842 </DOCNO>
Bose-Einstein condensation in trapped bosons: A Variational Monte Carlo


  Several properties of trapped hard sphere bosons are evaluated using
variational Monte Carlo techniques. A trial wave function composed of a
renormalized single particle Gaussian and a hard sphere Jastrow function for
pair correlations is used to study the sensitivity of condensate and
non-condensate properties to the hard sphere radius and the number of
particles. Special attention is given to diagonalizing the one body density
matrix and obtaining the corresponding single particle natural orbitals and
their occupation numbers for the system. The condensate wave function and
condensate fraction are then obtained from the single particle orbital with
highest occupation. The effect of interaction on other quantities such as the
ground state energy, the mean radial displacement, and the momentum
distribution are calculated as well. Results are compared with Mean Field
theory in the dilute limit.

</DOC>
<DOC>
<DOCNO> 84226 </DOCNO>
Gravitation, the Quantum, and Bohr's Correspondence Principle


  The black hole combines in some sense both the ``hydrogen atom'' and the
``black-body radiation'' problems of quantum gravity. This analogy suggests
that black-hole quantization may be the key to a quantum theory of gravity.
During the last twenty-five years evidence has been mounting that black-hole
surface area is indeed {\it quantized}, with {\it uniformally} spaced area
eigenvalues. There is, however, no general agreement on the {\it spacing} of
the levels. In this essay we use Bohr's correspondence principle to provide
this missing link. We conclude that the fundamental area unit is $4\hbar\ln3$.
This is the unique spacing consistent both with the area-entropy {\it
thermodynamic} relation for black holes, with Boltzmann-Einstein formula in
{\it statistical physics} and with {\it Bohr's correspondence principle}.

</DOC>
<DOC>
<DOCNO> 72195 </DOCNO>
Quantum Violations of the Equivalence Principle in a Modified


  Neutrino flavour oscillations are analyzed in a model in which particles
experience an effective Schwarzschild geometry modified by maximal acceleration
corrections. These imply a quantum violation of the equivalence principle. The
corresponding shifts in the phase of the neutrino mass eigenstates are
calculated and discussed.

</DOC>
<DOC>
<DOCNO> 151645 </DOCNO>
D-dimensional conformal sigma-models and their topological excitations


  A talk presented at International Conference ICMP-2000, London, England

</DOC>
<DOC>
<DOCNO> 116995 </DOCNO>
New Development in RF Pulse Compression


  Several pulse compression systems have been proposed for future linear
collider. Most of these systems require hundreds of kilometers of low-loss
waveguide runs. To reduce the waveguide length and improve the efficiency of
these systems, components for multimoding, active switches and non-reciprocal
elements are being developed. In the multimoded systems a waveguide is utilized
several times by sending different signals over different modes. The multimoded
components needed for these systems have to be able to handle hundreds of
megawatts of rf power at the X-band frequency and above. Consequently, most of
these components are overmoded. We present the development of multimoded
components required for such systems. We also present the development efforts
towards overmoded active component such as switches and overmoded
non-reciprocal components such as circulators and isolators.

</DOC>
<DOC>
<DOCNO> 121933 </DOCNO>
The FUSE Spectrum of PG0804+761: A Study of Atomic and MolecularGas in


  We present an analysis of interstellar and intergalactic absorption lines in
the FUSE spectrum of the low-redshift quasar PG0804+761 (z=0.100) at
intermediate resolution (FWHM=25 km/s) in the direction l=138.3, b=31.0. With a
good signal-to-noise ratio and the presence of several interesting Galactic and
extragalactic absorption components along the sight line, this spectrum
provides a good opportunity to demonstrate the ability of FUSE to do both
interstellar and extragalactic science. Although the spectrum of PG0804+761 is
dominated by strong absorption from local Galactic gas, we concentrate our
study on absorption by molecular hydrogen and neutral neutral and ionized
metals related to an intermediate-velocity cloud in the lower Galactic halo at
-55 km/s, and on absorption from OVI extended to negative velocities. In the
IVC, weak molecular hydrogen absorption is found in 5 lines for rotational
levels 0 and 1, leading to a total H_2 column density of log N = 14.71(+-0.30).
We derive an OI gas-phase abundance for the IVC of 1.03(+0.71-0.42) solar.
Absorption by OVI is found at velocities as negative as -110 km/s, but no
absorption from any species is found at velocities of -180 km/ where absorption
from the nearby high-velocity Complex A would be expected. We suggest that the
extended OVI absorption traces hot gas above the Perseus spiral arm. Finally,
we find intergalactic absorption by an intervening HI Ly betax absorber at
z=0.019 and absorption by HI, CIII and OVI in an associated system at z=0.102.
No intervening OVI absorbers are seen in the spectrum of PG0804+761.

</DOC>
<DOC>
<DOCNO> 84200 </DOCNO>
Quantum Inequalities in Curved Two Dimensional Spacetimes


  In quantum field theory there exist states for which the energy density is
negative. It is important that these negative energy densities satisfy
constraints, such as quantum inequalities, to minimize possible violations of
causality, the second law of thermodynamics, and cosmic censorship. In this
paper I show that conformally invariant scalar and Dirac fields satisfy quantum
inequalities in two dimensional spacetimes with a conformal factor that depends
on $x$ only or on $t$ only. These inequalities are then applied to two
dimensional black hole and cosmological spacetimes. It is shown that the bound
on the negative energies diverges to minus infinity as the event horizon or
initial singularity is approached. Thus, neglecting back reaction, negative
energies become unconstrained near the horizon or initial singularity. The
results of this paper also support the hypothesis that the quantum interest
conjecture applies only to deviations from the vacuum polarization energy, not
to the total energy.

</DOC>
<DOC>
<DOCNO> 100471 </DOCNO>
Quaternionic differential operators


  Motivated by a quaternionic formulation of quantum mechanics, we discuss
quaternionic and complex linear differential equations. We touch only a few
aspects of the mathematical theory, namely the resolution of the second order
differential equations with constant coefficients. We overcome the problems
coming out from the loss of the fundamental theorem of the algebra for
quaternions and propose a practical method to solve quaternionic and complex
linear second order differential equations with constant coefficients. The
resolution of the complex linear Schrodinger equation, in presence of
quaternionic potentials, represents an interesting application of the
mathematical material discussed in this paper.

</DOC>
<DOC>
<DOCNO> 69775 </DOCNO>
A Small Cosmological Constant, Grand Unification and Warped Geometry


  We will show that it is possible to obtain the observed value for the
four-dimensional cosmological constant \Lambda_4 by an exponential suppression
of an initially Planck-sized constant. It is a surprising feature that the
suppression-length corresponds to the GUT-scale. To make the relationship
explicit, we consider a set-up consisting of two positive tension domain-walls,
separated by a distance corresponding to the inverse of the GUT-scale and show
how a small \Lambda_4 is obtained through a warp-factor of the five-dimensional
theory. It is then pointed out, that the embedding of the set-up into IIB
string-theory naturally describes a spontaneously broken SU(6) SUSY GUT with
interesting consequences for the doublet-triplet splitting problem of
GUT-theories. Furthermore, the various hypercharge assignments of the SM fields
arise in a simple way from a consistency argument and composition of two sorts
of ``basic'' open string states.

</DOC>
<DOC>
<DOCNO> 122714 </DOCNO>
Unified Electronic Recombination Of Ne-like Fe XVII: Implications for


  Unified recombination cross sections and rates are computed for (e + Fe
XVIII) --> Fe XVII including non-resonant and resonant (radiative and
di-electronic recombination, RR and DR) processes in an ab initio manner with
relativistic fine structure. The highly resolved theoretical cross sections
exhibit considerably more resonance structures than observed in the heavy-ion
storage ring measurements at Heidelberg, Germany. Nonetheless, the detailed
resonance complexes agree well with experiment, and the unfiied rates agree
with the sum of experimentally derived DR and theoretical RR rates to ~ 20%,
within experimental or theoretical uncertainties. Theoretical results may
provide estimates of field ionization of rydberg levels close to the DR peak,
and non-resonant background contirbutions, particularly close to the RR peak as
E --> 0. More generally, the unified results avoid the physical and practical
problems in astrophysical models inherent in the separation of electronic
recombination into RR and DR on the one hand, and further subdivision into
low-energy Delta n = 0 DR and high-energy Delta n > 0 DR in photoionized and
collisionally ionized X-ray plasmas.

</DOC>
<DOC>
<DOCNO> 120647 </DOCNO>
Modeling the star formation in galaxies using the Chemo - dynamical SPH


  A new Chemo - Dynamical Smoothed Particle Hydrodynamic (CD - SPH) code is
presented. The disk galaxy is described as a multi - fragmented gas and star
system, embedded in a cold dark matter halo. The star formation (SF) process,
SNII, SNIa and PN events as well as chemical enrichment of gas have been
considered within the framework of the standard SPH model. Using this model we
describe the dynamical and chemical evolution of triaxial disk - like galaxies.
It is found that such approach provides a realistic description of the process
of formation, chemical and dynamical evolution of disk galaxies over a
cosmological timescale.

</DOC>
<DOC>
<DOCNO> 13845 </DOCNO>
Multiply charged metal cluster anions


  Formation, stability patterns, and decay channels of silver dianionic and
gold trianionic clusters are investigated with Penning-trap experiments and a
shell-correction method including shape deformations. The theoretical
predictions pertaining to the appearance sizes and electronic shell effects are
in remarkable agreement with the experiments. Decay of the multiply anionic
clusters occurs predominantly by electron tunneling through a Coulomb barrier,
rather than via fission, leading to appearance sizes unrelated to those of
multiply cationic clusters.

</DOC>
<DOC>
<DOCNO> 117908 </DOCNO>
Variable stars in the field of the globular cluster E3


  We present the results of a search for variable stars in the faint sparse
globular cluster E3. We have found two variable stars: an SX Phe variable (V1)
and a W UMa eclipsing binary (V2). We have applied period-luminosity and
period-color-luminosity relations to the variables to obtain their distance
moduli. V1 seems to be a blue straggler belonging to E3, based on its distance
modulus and location on the CMD. V2 is probably located behind the cluster, in
the Milky Way halo. We also present V/B-V and V/V-I color magnitude diagrams of
E3.

</DOC>
<DOC>
<DOCNO> 11107 </DOCNO>
High Reverse Breakdown A-C:H/Si Diodes Manufactured by rf-Pecvd


  Thin films of hydrogenated amorphous carbon (a-C:H) deposited by radio
frequency plasma-enhanced chemical vapour deposition (rf-PECVD) have been
studied for various applications. An interesting property of these films is
their high breakdown strength (107 Vcm-1). This property of a-C:H can be
exploited in high breakdown heterostructure diodes or as passivation layers and
insulator layers in MIS devices. Reports on the applications of a-C:H/Si diodes
exist in the literature. Diodes in which the a-C:H films have been deposited by
rf-PECVD, have been reported only once. In this article the diodes produced
reportedly failed to exhibit reproducible I-V characteristics under high
voltage stress. We have investigated the process dependence of structural and
electrical properties of rf-PECVD a-C:H films deposited at room temperature
from a CH4/Ar gas mixture (at a pressure of 100 mTorr) using a capacitively
coupled rf-PECVD. We observe a clear correlation between the dc-self bias and
the rectification ratio of a-C:H/Si heterojunction diodes. Optimised diodes
show rectification ratios upto 104 and a stable reverse breakdown voltage,
typically around 850 V. I-V and C-V measurements show no evidence of hystersis.
Scanning Electron Microscopy was carried out to determine the quality of the
films deposited. Micro-Raman analysis was used to estimate the ID/IG ratio in
the films deposited under different dc-self bias.

</DOC>
<DOC>
<DOCNO> 102296 </DOCNO>
On the Distribution of Conjugate Points along semi-Riemannian Geodesics


  Helfer in [Pacific J. Math. 164/2 (1994), p. 321--350] was the first to
produce an example of a spacelike Lorentzian geodesic with a continuum of
conjugate points. In this paper we show the following result: given an interval
$[a,b]$ of $IR$ and any closed subset $F$ of $IR$ contained in $]a,b]$, then
there exists a Lorentzian manifold $(M,g)$ and a spacelike geodesic
$\gamma:[a,b]\to M$ such that $\gamma(t)$ is conjugate to $\gamma(a)$ along
$\gamma$ iff $t\in F$.

</DOC>
<DOC>
<DOCNO> 12622 </DOCNO>
A non-perturbative treatment of the generalized Su-Schreiffer-Heeger


  Starting from the Hamiltonian for a dimer which includes all the electronic
and electron-phonon terms consistent with a non-degenerate orbital, by a
sequence of displacement and squeezing transformation we obtain an effective
polaronic Hamiltonian. The renormalized electronic interactions differ from the
results of semiclassical or perturbative treatments. The properties of the
variationally determined ground state of two particles in the orbital are
discussed for variable dimer length in the adiabatic limit.

</DOC>
<DOC>
<DOCNO> 117969 </DOCNO>
Recovering the Topology of the Initial Density Fluctuations Using the


  We apply the reconstruction technique of Nusser & Dekel (1992) to the
recently available Point Source Catalogue Redshift Survey (PSCz) in order to
subtract the phase correlations that are expected to develop in the mild
non-linear regime of gravitational evolution. We study the evolution of
isodensity contours defined using an adaptive smoothing algorithm in order to
minimize the problems derived from the non-comutivity of operators. We study
the genus curves of the fields thus obtained and concentrate on the evolution
of the amplitude drops, a meta-statistic able to quantify the level of
phase-correlation present in the field. In order to test the method and to
quantify the level of statistical uncertainty, we apply the method to a set of
mock PSCz catalogues derived from the N-body simulations of two 'standard' CDM
models, kindly granted to us by the Virgo consortium. We find the method to be
reliable in recovering the right amplitude drops. When applied to PSCz, the
level of phase correlations observed is very low on all scales ranging from
5h-1Mpc to 60 h-1Mpc, providing support to the theory that structure originated
from gaussian initial conditions.

</DOC>
<DOC>
<DOCNO> 117470 </DOCNO>
Looking for GRB progenitors


  Using stellar binary population synthesis code we calculate the production
rates and lifetimes of several types of possible GRB progenitors. We consider
mergers of double neutron stars, black hole neutron stars, black hole white
dwarfs and helium star mergers. We calibrate the results with the measured star
formation rate history. We discuss the viability of each GRB model, and
alternatively assuming that all bursts are connected with one model we
constrain the required collimation of GRBs. We also show the importance of
widely used evolutionary parameters on the merger rates of calculated binary
populations.

</DOC>
<DOC>
<DOCNO> 9694 </DOCNO>
Exact Solution of Return Hysteresis Loops in One Dimensional Random


  Minor hysteresis loops within the main loop are obtained analytically and
exactly in the one-dimensional ferromagnetic random field Ising-model at zero
temperature. Numerical simulations of the model show excellent agreement with
the analytical results.

</DOC>
<DOC>
<DOCNO> 116938 </DOCNO>
Status Report on the 5 Mev Iphi RFQ


  A 5-MeV RFQ designed for a proton current up to 100-mA CW is now under
construction as part of the High Intensity Proton Injector project (IPHI). Its
computed transmission is greater than 99 %. The main goals of the project are
to verify the accuracy of the design codes, to gain the know-how on
fabrication, tuning procedures and operations, to measure the output beam
characteristics in order to optimise the higher energy part of the linac, and
to reach a high availability with minimum beam trips. A cold model has been
built to develop the tuning procedure. The present status of the IPHI RFQ is
presented.

</DOC>
<DOC>
<DOCNO> 151597 </DOCNO>
Fusion Rings Related to Affine Weyl Groups


  The construction of the fusion ring of a quasi-rational CFT based on
$\hat{sl}(3)_k$ at generic level $k\not \in {\Bbb Q}$ is reviewed. It is a
commutative ring generated by formal characters, elements in the group ring
${\Bbb Z}[\tilde{W}]$ of the extended affine Weyl group $\tilde{W}$ of
$\hat{sl}(3)_k$. Some partial results towards the $\hat{sl}(4)_k$
generalisation of this character ring are presented.

</DOC>
<DOC>
<DOCNO> 152097 </DOCNO>
Comment on ``Dimensional and dynamical aspects of the Casimir effect:


  In [hep-th/0009173] Milton has presented a brief review of some interesting
aspects of the theory of the Casimir effect. This comment is aimed at
correcting some imprecise statements in that work with respect to the relevance
of the Casimir effect for explaining the phenomenon of sonoluminescence.

</DOC>
<DOC>
<DOCNO> 40097 </DOCNO>
Experimental evidence for a light and broad scalar resonance in $D^+\to


  From a sample of $1172 \pm 61$ $D^+ \to \pi^- \pi^+ \pi^+$ decay, we find
$\Gamma (D^+ \to \pi^- \pi^+ \pi^+) / \Gamma (D^+ \to K^- \pi^+ \pi^+) =
  0.0311 \pm 0.0018 ^{+0.0016}_{-0.0026}$. Using a coherent amplitude analysis
to fit the Dalitz plot of this decays, we find strong evidence that a scalar
resonance of mass $478^{+24}_{-23} \pm 17$ MeV/$c^2$ and width $324^{+42}_{-40}
\pm 21$ MeV/$c^2$ accounts for approximately half of all decays.

</DOC>
<DOC>
<DOCNO> 69473 </DOCNO>
Random values of the cosmological constant


  One way that an anthropic selection mechanism may be manifest in a physical
theory involves multiple domains in the universe with different values of the
physical parameters. If this mechanism is to be relevant for understanding the
small observed value of the cosmological constant, it may involve a mechanism
by which some contributions to the cosmological constant can be fixed at a
continuous range of values in the different domains. I study the properties of
four possible mechanisms, including the possibility of the Hubble damping of a
scalar field with an extremely flat potential. Another interesting possibility
involves fixed random values of non-dynamical form fields, and a cosmological
mechanism is suggested. This case raises the possibility of anthropic selection
of other parameters in addition. Further requirements needed for a consistent
cosmology are discussed.

</DOC>
<DOC>
<DOCNO> 70225 </DOCNO>
The Fayet-Iliopoulos D-term and its renormalisation in softly-broken


  We consider the renormalisation of the Fayet-Iliopoulos D-term in a
softly-broken abelian supersymmetric theory, and calculate the associated
beta-function through three loops. We show that there exists (at least through
three loops) a renormalisation group invariant trajectory for the coefficient
of the D-term, corresponding to the conformal anomaly solution for the soft
masses and couplings.

</DOC>
<DOC>
<DOCNO> 99800 </DOCNO>
Complemented subspaces of products of Banach spaces


  We show that complemented subspaces of uncountable products of Banach spaces
are products of complemented subspaces of countable subproducts.

</DOC>
<DOC>
<DOCNO> 178572 </DOCNO>
Electromagnetic moments of relativistic higher spin baryons


  We point out a source of ambiguities in the measurements of the
electromagnetic moments of spin-3/2 baryons which rely on relativistic
Lagrangian models. An anambiguous relation between the parameters of the
spin-3/2 electromagnetic Lagrangian and the electromagnetic moments of the
spin-3/2 particle exits in general only for on-shell situation, while the
measurements are done on ``virtual'' baryons.

</DOC>
<DOC>
<DOCNO> 13117 </DOCNO>
Glassy Slowing of Stripe Modulation in (La,Eu,Nd)(2-x)(Sr,Ba)(x)CuO4: A


  We report a comprehensive Cu and La NQR study down to 350mK in the stripe
phase of the hole-doped high temperature superconductors with hole
concentration approximately 1/8. We observe the hyperfine broadened NQR
lineshape only below 8-20K for x=1/8, indicating that the ordered moments
continue to fluctuate slowly even below the temperature range where they appear
static in other measurements. Detailed numerical simulations of the Zeeman
perturbed Cu NQR lineshape establish that widely accepted models of periodic
modulation of spin density waves with maximum moment approxiamtely 0.3mu_B can
not account for the NQR lineshape. These results suggest that significant
disorder exists at NQR time scales. By fitting a single model to several sets
of experimental data, we deduce the spatial distribution of the spin
fluctuation frequency scale and its temperature dependence. Our results
indicate that as soon as charge dynamics slow down, the spin fluctuationsbegin
to slow dramatically with spin stiffness approximately 200K. However, the
motional narrowing feature observed in the Zeeman perturbed NQR measurements
suggest that the slowing of the spin fluctuations levels off at frequencies
somewhat below the NQR frequency. By extending the analysis to other hole
concentrations, we find a qualitative difference above and below x=1/8.

</DOC>
<DOC>
<DOCNO> 101837 </DOCNO>
Counting generic genus-0 curves on Hirzebruch surfaces


  Hirzebruch surfaces provide an excellent example to underline the fact that
in general symplectic manifolds, Gromov-Witten invariants might well count
curves in the boundary components of the moduli space. We use this example to
explain in detail that the counting argument given by Batyrev in "Quantum
cohomology rings of toric manifolds" (Asterisque 218:9-34, 1993) does not work.

</DOC>
<DOC>
<DOCNO> 11814 </DOCNO>
Renormalization group flow with unstable particles


  The renormalization group flow of an integrable two dimensional quantum field
theory which contains unstable particles is investigated. The analysis is
carried out for the Virasoro central charge and the conformal dimensions as a
function of the renormalization group flow parameter. This allows to identify
the corresponding conformal field theories together with their operator content
when the unstable particles vanish from the particle spectrum. The specific
model considered is the $SU(3)_{2}$-homogeneous Sine-Gordon model.

</DOC>
<DOC>
<DOCNO> 100817 </DOCNO>
Construction of Miniversal Deformations of Lie Algebras


  We consider deformations of finite or infinite dimensional Lie algebras over
a field of characteristic 0. There is substantial confusion in the literature
if one tries to describe all the non-equivalent deformations of a given Lie
algebra. It is known that there is in general no "universal" deformation of the
Lie algebra L with a commutative algebra base A with the property that for any
other deformation of L with base B there exists a unique homomorphism f: A -> B
that induces an equivalent deformation. Thus one is led to seek a "miniversal"
deformation. For a miniversal deformation such a homomorphism exists, but is
unique only at the first level. If we consider deformations with base spec A,
where A is a local algebra, then under some minor restrictions there exists a
miniversal element. In this paper we give a construction of a miniversal
deformation.

</DOC>
<DOC>
<DOCNO> 120454 </DOCNO>
Constraints over Cosmological Constant and Quintessence Fields in an


  A brief account of the current cosmological observations is given and their
implications for QCDM and $\Lambda$CDM cosmologies are discussed. The
nucleosynthesis and the galaxy formation constraints have been used to put
limits on $\Omega_\phi$ during cosmic evolution, and develop a realistic
approach to the tracking behaviour of quintessence fields. The astrophysical
constraints are applied to interpolate the value of the tracking parameter
$\epsilon \simeq 0.75$ at the present epoch and also to find the lower and the
upper limits for $\Lambda$ in the accelerating universe. It is shown that the
transition from deceleration to acceleration in the cosmic expansion occurs
earlier in $\Lambda$CDM cosmology compared to QCDM cosmology.

</DOC>
<DOC>
<DOCNO> 102393 </DOCNO>
Random Lattices and Random Sphere Packings: Typical Properties


  We review results about the density of typical lattices in $R^n.$ They state
that such density is of the order of $2^{-n}.$ We then obtain similar results
for random packings in $R^n$: after taking suitably a fraction $\nu$ of a
typical random packing $\sigma$, the resulting packing $\tau$ has density
$C(\nu) 2^{-n},$ with a reasonable $C(\nu).$ We obtain estimates on $C(\nu).$

</DOC>
<DOC>
<DOCNO> 39996 </DOCNO>
GNO Solar Neutrino Observations: Results for GNOI


  We report the first GNO solar neutrino results for the measuring period GNOI,
solar exposure time May 20, 1998 till January 12, 2000. In the present
analysis, counting results for solar runs SR1 - SR19 were used till April 4,
2000. With counting completed for all but the last 3 runs (SR17 - SR19), the
GNO I result is [65.8 +10.2 -9.6 (stat.) +3.4 -3.6 (syst.)]SNU (1sigma) or
[65.8 + 10.7 -10.2 (incl. syst.)]SNU (1sigma) with errors combined. This may be
compared to the result for Gallex(I-IV), which is [77.5 +7.6 -7.8 (incl.
syst.)] SNU (1sigma). A combined result from both GNOI and Gallex(I-IV)
together is [74.1 + 6.7 -6.8 (incl. syst.)] SNU (1sigma).

</DOC>
<DOC>
<DOCNO> 116675 </DOCNO>
Correlation property of length sequences based on global structure of


  This paper considers three kinds of length sequences of the complete genome.
Detrended fluctuation analysis, spectral analysis, and the mean distance
spanned within time $L$ are used to discuss the correlation property of these
sequences. The values of the exponents from these methods of these three kinds
of length sequences of bacteria indicate that the long-range correlations exist
in most of these sequences. The correlation have a rich variety of behaviours
including the presence of anti-correlations. Further more, using the exponent
$\gamma$, it is found that these correlations are all linear ($\gamma=1.0\pm
0.03$). It is also found that these sequences exhibit $1/f$ noise in some
interval of frequency ($f>1$). The length of this interval of frequency depends
on the length of the sequence. The shape of the periodogram in $f>1$ exhibits
some periodicity. The period seems to depend on the length and the complexity
of the length sequence.

</DOC>
<DOC>
<DOCNO> 84879 </DOCNO>
Functional Approach to Quantum Decoherence and the Classical Final


  Decoherence and the approach to the classical final limit are studied in two
similar cases: the Mott and the Cosmological problems.

</DOC>
<DOC>
<DOCNO> 69163 </DOCNO>
SIMP (Strongly Interacting Massive Particle) Search


  We consider laboratory experiments that can detect stable, neutral strongly
interacting massive particles (SIMPs). We explore the SIMP annihilation cross
section from its minimum value (restricted by cosmological bounds) to the barn
range, and vary the mass values from a GeV to a TeV. We also consider the
prospects and problems of detecting such particles at the Tevatron.

</DOC>
<DOC>
<DOCNO> 11078 </DOCNO>
A series representation of the nonlinear equation for axisymmetrical


  Whatever the fluid lipid vesicle is modeled as the spontaneous-curvature,
bilayer-coupling, or the area-difference elasticity, and no matter whether a
pulling axial force applied at the vesicle poles or not, a universal shape
equation presents when the shape has both axisymmetry and up-down symmetry.
This equation is a second order nonlinear ordinary differential equation about
the sine $sin\psi (r)$ of the angle $\psi (r)$ between the tangent of the
contour and the radial axis $r$. However, analytically there is not a generally
applicable method to solve it, while numerically the angle $\psi (0)$ can not
be obtained unless by tricky extrapolation for $r=0$ is a singular point of the
equation. We report an infinite series representation of the equation, in which
the known solutions are some special cases, and a new family of shapes related
to the membrane microtubule formation, in which $sin\psi (0)$ takes values from
0 to $\pi /2$, is given.

</DOC>
<DOC>
<DOCNO> 11347 </DOCNO>
The structure of scientific collaboration networks


  We investigate the structure of scientific collaboration networks. We
consider two scientists to be connected if they have authored a paper together,
and construct explicit networks of such connections using data drawn from a
number of databases, including MEDLINE (biomedical research), the Los Alamos
e-Print Archive (physics), and NCSTRL (computer science). We show that these
collaboration networks form "small worlds" in which randomly chosen pairs of
scientists are typically separated by only a short path of intermediate
acquaintances. We further give results for mean and distribution of numbers of
collaborators of authors, demonstrate the presence of clustering in the
networks, and highlight a number of apparent differences in the patterns of
collaboration between the fields studied.

</DOC>
<DOC>
<DOCNO> 120541 </DOCNO>
The Baryon Content of Groups and Clusters of Galaxies


  We have analyzed the properties of a sample of 33 groups and clusters of
galaxies and examine the baryon content to check for trends over a decade in
temperature down to 1 keV. We examine the relative contribution of galaxies and
ICM to baryons in clusters through the gas-to-stellar mass ratio and find that
the typical stellar contribution to the baryonic mass is between 5 and 20%.
This ratio is found to be roughly independent of temperature. Therefore, we do
not confirm the trend of increasing gas-to-stellar mass ratio with increasing
temperature as previously claimed. We also determine distribution of the baryon
fraction with the density contrast. Virial masses are estimated from two
different mass estimators: one based on the isothermal hydrostatic equation
(IHE), the other based on scaling law models (SLM). Comparing the two methods,
we find that SLM lead to less dispersed baryon fractions over all density
contrasts and that the derived mean absolute valuesare significantly lower than
IHE mean values. We show that this is not due to the uncertainties on the outer
slope $\beta$ of the gas density profile but is rather indicating that IHE
masses are less reliable. Examining the shape of the baryon fraction profiles
we find that cluster baryon fractions estimated from SLM follow a scaling law.
Moreover, we do not find any strong evidence of increasing baryon (gas)
fraction with temperature, neither do we find the slope $\beta$ to increase
with temperature. The absence of clear trends between $f_{b}$ and
$M_{gas}/M_{*}$ with temperature is consistent with the similarity of baryon
fraction profiles and suggests that non-gravitational processes such as galaxy
feedback, do not play a dominant r\^ole in heating the intra-cluster gas on the
virial scale.

</DOC>
<DOC>
<DOCNO> 116884 </DOCNO>
Industrial Fabrication of Medium-Beta SCRF Cavities for a High-Intensity


  During 1999, four 700-MHz, medium-beta (b = 0.64), superconducting radio
frequency (SCRF) cavities for a high-intensity proton linac project at Los
Alamos National Laboratory (LANL) were manufactured by industry. The SCRF
cavities were designed by a LANL team in Los Alamos, New Mexico, USA, and
manufactured at a CERCA plant in Romans, France. The cavities were made of
4-mm-thick, solid niobium sheets with a residual resistivity ratio (RRR)
greater than 250. These niobium sheets were supplied by Wah Chang (USA),
Heraeus AG (Germany), and Tokyo Denkai (Japan). The SCRF cavities were shipped
to LANL for performance testing. This paper describes the experience gained
during the manufacturing process at CERCA.

</DOC>
<DOC>
<DOCNO> 8238 </DOCNO>
Does Giant Magnetoresistance Survive in Presence of Superconducting


  The giant magnetoresistance (GMR) of ferromagnetic bilayers with a
superconducting contact (F1/F2/S) is calculated in ballistic and diffusive
regimes. As in spin-valve, it is assumed that the magnetization in the two
ferromagnetic layers F1 and F2 can be changed from parallel to antiparallel. It
is shown that the GMR defined as the change of conductance between the two
magnetic configurations is an oscillatory function of the thickness of F2 layer
and tends to an asymptotic positive value at large thickness. This is due to
the formation of quantum well states in F2 induced by Andreev reflection at the
F2/S interface and reflection at F1/F2 interface in antiparallel configuration.
In the diffusive regime, if only spin-dependent scattering rates in the
magnetic layers are considered (no difference in Fermi wave-vectors between
spin up and down electrons) then the GMR is supressed due to the mixing of spin
up and down electron-hole channels by Andreev reflection.

</DOC>
<DOC>
<DOCNO> 101910 </DOCNO>
Localization for One Dimensional, Continuum, Bernoulli-Anderson Models


  We use scattering theoretic methods to prove strong dynamical and exponential
localization for one dimensional, continuum, Anderson-type models with singular
distributions; in particular the case of a Bernoulli distribution is covered.
The operators we consider model alloys composed of at least two distinct types
of randomly dispersed atoms. Our main tools are the reflection and transmission
coefficients for compactly supported single site perturbations of a periodic
background which we use to verify the necessary hypotheses of multi-scale
analysis. We show that non-reflectionless single sites lead to a discrete set
of exceptional energies away from which localization occurs.

</DOC>
<DOC>
<DOCNO> 68785 </DOCNO>
Supersymmetric Electroweak Corrections to $W^{\pm}H^{\mp}$ Associated


  The $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew}
m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the cross section
for $W^{\pm}H^{\mp}$ associated production at the LHC are calculated in the
minimal supersymmetric standard model. Those corrections arise from the quantum
effects which are induced by the Yukawa couplings from the Higgs sector and the
genuine supersymmetric electroweak couplings involving supersymmetric
particles, i.e. chargino-top(bottom)-sbottom(stop) couplings,
neutralino-top(bottom)-stop(sbottom) couplings and charged Higgs-stop-sbottom
couplings. The Yukawa corrections can decrease the total cross sections
significantly for low $\tan\beta(<4)$ when $m_{H^+}<300$GeV, which exceed -12%.
For high $\tan\beta$ the Yukawa corrections become negligibly small. The
genuine supersymmetric electroweak corrections can increase or decrease the
total cross sections depending on the supersymmetric parameters, which are at
most a few percent, except the region near the threshold. We also show that the
genuine supersymmetric electroweak corrections depend strongly on the choice of
$\tan\beta$, $A_t$, $M_{\tilde Q}$ and $\mu$. For large values of $A_t$, or
large values of $\mu$ and $\tan\beta$, one can get larger corrections. The
corrections can become very small, in contrast, for larger values of $M_{\tilde
Q}$.

</DOC>
<DOC>
<DOCNO> 99493 </DOCNO>
Simple Divisibility Rules for the 1st 1000 Prime Numbers


  Simple divisibility rules are given for the 1st 1000 prime numbers.

</DOC>
<DOC>
<DOCNO> 84925 </DOCNO>
Non-vacuum twisting type N metrics


  A maximally reduced system of equations corresponding to the twisting type N
Einstein metrics is given. When the cosmological constant $\lambda\to 0$ they
reduce to the standard equations for the vacuum twisting type N's. All the
metrics which are conformally equivalent to the twisting type N metrics and
which admit 3-dimensional conformal group of symmetries are presented. In the
Feferman class of metrics an example is given of a twisting type N metric which
satisfies Bach's equations but is not Einstein.

</DOC>
<DOC>
<DOCNO> 70716 </DOCNO>
Is the $\sigma(600)$ a Glueball? Two photon reactions can tell us


  Minkowski and Ochs have recently argued that the small two photon coupling of
a conjectured $\sigma(600)$ is so small that it is likely to be a glueball. We
ask whether this can be so or whether it is simply gauge invariance that
produces the observed low mass suppression?

</DOC>
<DOC>
<DOCNO> 9513 </DOCNO>
First-principles study of lattice instabilities in Ba_xSr_(1-x)TiO_3


  Using first-principles calculations based on a variational density functional
perturbation theory, we investigate the lattice dynamics of solid solutions of
barium and strontium titanates. Averaging the information available for the
related pure compounds yields results equivalent to those obtained within the
virtual crystal approximation, providing frequencies which are a good
approximation to those computed for a (111) ordered supercell. Using the same
averaging technique we report the evolution of the ferroelectric and
antiferrodistortive instabilities with composition.

</DOC>
<DOC>
<DOCNO> 71166 </DOCNO>
DVCS on the nucleon to the twist-3 accuracy


  The amplitude of the deeply virtual Compton scattering off nucleon is
computed to the twist-3 accuracy in the Wandzura-Wilczek (WW) approximation.
The result is presented in the form which can be easily used for the analysis
of DVCS observables.

</DOC>
<DOC>
<DOCNO> 69646 </DOCNO>
Smoothed Particle Hydrodynamics for Relativistic Heavy Ion Collisions


  The method of smoothed particle hydrodynamics (SPH) is developped
appropriately for the study of relativistic heavy ion collision processes. In
order to describe the flow of a high energy but low baryon number density
fluid, the entropy is taken as the SPH base. We formulate the method in terms
of the variational principle. Several examples show that the method is very
promising for the study of hadronic flow in RHIC physics.

</DOC>
<DOC>
<DOCNO> 150739 </DOCNO>
Three-Loop Four-Point Correlator in N=4 SYM


  We explicitly compute the complete three-loop (O(g^4)) contribution to the
four-point function of chiral primary current-like operators <(q)^2 q^2 (q)^2
q^2> in any finite N=2 SYM theory. The computation uses N=2 harmonic
supergraphs in coordinate space. Dramatic simplifications are achieved by a
double insertion of the N=2 SYM linearized action, and application of
superconformal covariance arguments to the resulting nilpotent six-point
amplitude. The result involves polylogarithms up to fourth order of the
conformal cross ratios. It becomes particularly simple in the N=4 special case.

</DOC>
<DOC>
<DOCNO> 69640 </DOCNO>
Deep Inelastic Scattering Data and the Problem of Saturation in Small-x


  We investigate the role of unitarization effects in virtual photon-proton
(\gamma^*p) interactions at small x. The q\bar{q}-fluctuation of the initial
photon is separated into a small distance and a large distance component and a
model for the unitarization of each component is proposed. The Born
approximation for the small size component is calculated using QCD perturbation
theory. Reggeon diagram technique is used in order to obtain a self-consistent
scheme for both total \gamma^*p cross section and diffractive production. The
model gives a good description of HERA data in the small-x region, with a
single Pomeron of intercept 1.2.

</DOC>
<DOC>
<DOCNO> 119664 </DOCNO>
The Detection Rate of Molecular Gas in Elliptical Galaxies: Constraints


  In order to constrain parameters in galaxy formation theories, especially
those for a star formation process, we investigate cold gas in elliptical
galaxies. We calculate the detection rate of cold gas in them using a
semi-analytic model of galaxy formation and compare it with observations. We
show that the model with a long star formation time-scale (~20 Gyr) is
inconsistent with observations. Thus, some mechanisms of reducing the mass of
interstellar medium, such as the consumption of molecular gas by star formation
and/or reheating from supernovae, are certainly effective in galaxies. Our
model predicts that star formation induced when galaxies in a halo collide each
other reduces the cold gas left until the present. However, we find that the
reduction through random collisions of satellite (non-central) galaxies in mean
free time-scale in a halo is not required to explain the observations. This may
imply that the collisions and mergers between satellite galaxies do not occur
so often in clusters or that they do not stimulate the star formation activity
as much as the simple collision model we adopted. For cD galaxies, the
predicted detection rate of cold gas is consistent with observations as long as
the transformation of hot gas into cold gas is prevented in halos whose
circular velocities are larger than 500 km s^-1. Moreover, we find that the
cold gas brought into cDs through captures of gas-rich galaxies is little. We
also show that the fraction of galaxies with observable cold gas should be
small for cluster ellipticals in comparison with that for field ellipticals.

</DOC>
<DOC>
<DOCNO> 71976 </DOCNO>
Is Anomalous Production of Omega and anti-Omega Evidence for Disoriented


  No conventional picture of nucleus-nucleus collisions has yet been able to
explain the abundance of Omega and anti-Omega hyperons in central collisions
between Pb nuclei at 158 A GeV at the CERN SPS. We argue that this is evidence
that they are produced as topological defects arising from the formation of
disoriented chiral condensates (DCC) with an average domain size of about 2 fm.

</DOC>
<DOC>
<DOCNO> 70676 </DOCNO>
The Light-Cone Fock Expansion in Quantum Chromodynamics


  A fundamental question in QCD is the non-perturbative structure of hadrons at
the amplitude level--not just the single-particle flavor, momentum, and
helicity distributions of the quark constituents, but also the multi-quark,
gluonic, and hidden-color correlations intrinsic to hadronic and nuclear
wavefunctions. The light-cone Fock-state representation of QCD encodes the
properties of a hadrons in terms of frame-independent wavefunctions. A number
of applications are discussed, including semileptonic B decays, deeply virtual
Compton scattering, and dynamical higher twist effects in inclusive reactions.
A new type of jet production reaction, "self-resolving diffractive
interactions" can provide direct information on the light-cone wavefunctions of
hadrons in terms of their quark and gluon degrees of freedom as well as the
composition of nuclei in terms of their nucleon and mesonic degrees of freedom.
The relation of the intrinsic sea to the light-cone wavefunctions is discussed.
The physics of light-cone wavefunctions is illustrated for the quantum
fluctuations of an electron.

</DOC>
<DOC>
<DOCNO> 68650 </DOCNO>
Pair production of neutralinos via gluon-gluon collisions


  The production of a neutralino pair via gluon-gluon fusion is studied in the
minimal supersymmetric model(MSSM) at proton-proton colliders. The numerical
analysis of their production rates are carried out in the mSUGRA scenario. The
results show that this cross section may reach about 80 femto barn for
 $\tilde{\chi}^{0}_{1}\tilde{\chi}^{0}_{2}$ pair production and 23 femto barn
for $\tilde{\chi}^{0}_{2}\tilde{\chi}^{0}_{2}$ pair production with suitable
input parameters at the future LHC collider. It shows that this loop mediated
process can be competitive with the quark-antiquark annihilation process at the
LHC.

</DOC>
<DOC>
<DOCNO> 119922 </DOCNO>
Gauge choice and geodetic deflection in conformal gravity


  Conformal gravity has been proposed as an alternative theory of gravity which
can account for flat galactic rotation curves without recourse to copious
quantities of dark matter. However it was shown that for the usual choice of
the metric, the result is catastrophic for null or highly relativistic
geodesics, the effect is exactly the opposite yielding an effective repulsion
and less deflection in this case. It is the point of this paper, that any
result for massive geodesics depends on the choice of conformal gauge, in
contradistinction to the case of null geodesics. We show how it is possible to
choose the gauge so that the theory is attractive for all geodesics.

</DOC>
<DOC>
<DOCNO> 83399 </DOCNO>
Data Mining in Astronomical Databases


  A Virtual Observatory (VO) will enable transparent and efficient access,
search, retrieval, and visualization of data across multiple data repositories,
which are generally heterogeneous and distributed. Aspects of data mining that
apply to a variety of science user scenarios with a VO are reviewed.

</DOC>
<DOC>
<DOCNO> 40138 </DOCNO>
Signals for Gauge Mediated Supersymmetry Breaking Model at an {${\bf


  We study the pair-production and decay of right handed selectrons within a
Gauge Mediated Supersymmetry Breaking Model in polarised $e^-e^-$ interaction.
Detailed analyses of the possible signals and backgrounds are performed for a
few selected points in the parameter space. A judicious choice for polarisation
of the initial electron beam helps eliminate almost the entire Standard Model
background. We also show that phase space distributions can be used to
distinguish such a supersummetry breaking scheme from the supergravity inspired
models.

</DOC>
<DOC>
<DOCNO> 83140 </DOCNO>
Linear Tabulated Resolution Based on Prolog Control Strategy


  Infinite loops and redundant computations are long recognized open problems
in Prolog. Two ways have been explored to resolve these problems: loop checking
and tabling. Loop checking can cut infinite loops, but it cannot be both sound
and complete even for function-free logic programs. Tabling seems to be an
effective way to resolve infinite loops and redundant computations. However,
existing tabulated resolutions, such as OLDT-resolution, SLG- resolution, and
Tabulated SLS-resolution, are non-linear because they rely on the
solution-lookup mode in formulating tabling. The principal disadvantage of
non-linear resolutions is that they cannot be implemented using a simple
stack-based memory structure like that in Prolog. Moreover, some strictly
sequential operators such as cuts may not be handled as easily as in Prolog.
  In this paper, we propose a hybrid method to resolve infinite loops and
redundant computations. We combine the ideas of loop checking and tabling to
establish a linear tabulated resolution called TP-resolution. TP-resolution has
two distinctive features: (1) It makes linear tabulated derivations in the same
way as Prolog except that infinite loops are broken and redundant computations
are reduced. It handles cuts as effectively as Prolog. (2) It is sound and
complete for positive logic programs with the bounded-term-size property. The
underlying algorithm can be implemented by an extension to any existing Prolog
abstract machines such as WAM or ATOAM.

</DOC>
<DOC>
<DOCNO> 70032 </DOCNO>
Large N_c in chiral perturbation theory


  The construction of the effective Lagrangian relevant for the mesonic sector
of QCD in the large N_c limit meets with a few rather subtle problems. We
thoroughly examine these and show that, if the variables of the effective
theory are chosen suitably, the known large N_c counting rules of QCD can
unambiguously be translated into corresponding counting rules for the effective
coupling constants. As an application, we demonstrate that the Kaplan-Manohar
transformation is in conflict with these rules and is suppressed to all orders
in 1/N_c. The anomalous dimension of the axial singlet current generates an
additional complication: The corresponding external field undergoes
nonmultiplicative renormalization. As a consequence, the Wess-Zumino-Witten
term, which accounts for the U(3)_R x U(3)_L anomalies in the framework of the
effective theory, contains pieces that depend on the running scale of QCD. The
effect only shows up at nonleading order in 1/N_c, but requires specific
unnatural parity contributions in the effective Lagrangian that restore
renormalization group invariance.

</DOC>
<DOC>
<DOCNO> 102079 </DOCNO>
The groups of PL and Lipschitz homeomorphisms of noncompact 2-manifolds


  Suppose M is a noncompact connected PL 2-manifold. In this paper we study the
topological property of the triple (H(M)_0, H^PL(M)_0, H^PL, c(M)_0), where
H(M)_0 is the identity component of the homeomorphism group {\cal H}(M) of M
with the compact-open topology, and H^PL(M)_0 and H^PL, c(M)_0 are the identity
components of the subgroups consisting of PL-homeomorphisms of M and ones with
compact supports. We show that this triple is a
(s^infty,sigma^infty,sigma^infty_f)-manifold and determine its topological
type. We also study the subgroups of Lipschitz homeomorphisms.

</DOC>
<DOC>
<DOCNO> 80809 </DOCNO>
From Monte Carlo Integration to Quantum Chromo Dynamics (an


  In these lectures we provide a short introduction to the Monte Carlo
integration method and its applications. We show how the origin of ultraviolet
divergences if Field Theories is in the undefined formal product of
distributions and how one can define the Path Integral in terms of regularized
distributions in order to cancel these divergences. This technique provides the
only non perturbative regularization procedure of continuum Field Theories and,
at the same time, provides a practical method to compute correlation (Green)
functions (using Monte Carlo integration for the regularized path integrals).
We then apply these tools to formulate QCD on a lattice. Some of the examples
are accompanied by complete computer programs.

</DOC>
<DOC>
<DOCNO> 71889 </DOCNO>
Rotating Super Black Hole as Spinning Particle


  We give a review of the works devoted to the treatment of the Kerr super
black hole solution as a spinning particle. The real, complex and stringy
structures of the Kerr and super-Kerr geometries are discussed, as well as the
recent results on the regular matter source for the Kerr spinning particle. It
is shown that the source has to represent a rotating bag-like bubble having
(A)dS interior and a smooth domain wall boundary. The given by Morris
supersymmetric generalization of the U(I) x U'(I) field model (which was used
by Witten to describe cosmic superconducting strings) is considered, and it is
shown that this model can be adapted for description of superconducting bags
having a long range external electromagnetic field and another gauge field
confined inside the bag.

</DOC>
<DOC>
<DOCNO> 101717 </DOCNO>
A Note on Extensions of Infinitary Logic


  We show that a strong form of the so called Lindstrom's Theorem fails to
generalize to extensions of L_{kappa,omega} and L_{kappa,kappa}: For weakly
compact kappa there is no strongest extension of L_{kappa,omega} with the
(kappa,kappa)-compactness property and the Lowenheim-Skolem theorem down to
kappa. With an additional set-theoretic assumption, there is no strongest
extension of L_{kappa,kappa} with the (kappa,kappa)-compactness property and
the Lowenheim-Skolem theorem down to <kappa.

</DOC>
<DOC>
<DOCNO> 9651 </DOCNO>
Motional dressed states in a Bose condensate: Superfluidity at


  We present an exact analytic solution of a nonlinear Schr\"odinger field
interacting with a moving potential (obstacle) at supersonic speed. We show
that the field forms a stable shape-invariant structure localized around the
obstacle --- a dressing effect that protects the field against excitations by
the obstacle.

</DOC>
<DOC>
<DOCNO> 14037 </DOCNO>
Bose-Einstein condensation of excitons in Cu$_2$O


  We present a parameter-free model which estimates the density of excitons in
Cu$_2$O, related to experiments that have tried to create an excitonic
Bose-Einstein condensate. Our study demonstrates that the triplet-state
excitons move along adiabats and obey classical statistics, while the
singlet-state excitons are a possible candidate for forming a Bose-Einstein
condensate. Finally we show that the results of this study do not change
qualitatively in a two-dimensional exciton gas, which can be realized in a
quantum well.

</DOC>
<DOC>
<DOCNO> 151854 </DOCNO>
D-dimensional massless particle with extended gauge invariance


  We propose the model of $D-$dimensional massless particle whose Lagrangian is
given by the $N-$th extrinsic curvature of world-line. The system has $N+1$
gauge degrees of freedom constituting $W-$like algebra; the classical
trajectories of the model are space-like curves which obey the conditions
$k_{N+a}=k_{N-a}$, $k_{2N}=0$, $a=1,...,N-1$, $N\leq[(D-2)/2]$, while the first
$N$ curvatures $k_i$ remain arbitrary. We show that the model admits consistent
formulation on the anti-De Sitter space. The solutions of the system are the
massless irreducible representations of Poincar\'e group with $N$ nonzero
helicities, which are equal to each other.

</DOC>
<DOC>
<DOCNO> 83282 </DOCNO>
Trainable Methods for Surface Natural Language Generation


  We present three systems for surface natural language generation that are
trainable from annotated corpora. The first two systems, called NLG1 and NLG2,
require a corpus marked only with domain-specific semantic attributes, while
the last system, called NLG3, requires a corpus marked with both semantic
attributes and syntactic dependency information. All systems attempt to produce
a grammatical natural language phrase from a domain-specific semantic
representation. NLG1 serves a baseline system and uses phrase frequencies to
generate a whole phrase in one step, while NLG2 and NLG3 use maximum entropy
probability models to individually generate each word in the phrase. The
systems NLG2 and NLG3 learn to determine both the word choice and the word
order of the phrase. We present experiments in which we generate phrases to
describe flights in the air travel domain.

</DOC>
<DOC>
<DOCNO> 68246 </DOCNO>
Meson Masses in High Density QCD


  The low-energy effective theories for the two- and three-flavor
color-superconductors arising in the high density limit of QCD are discussed.
Using an effective field theory to describe quarks near the fermi surface, we
compute the masses of the pseudo-Goldstone bosons that dominate the
low-momentum dynamics of these systems.

</DOC>
<DOC>
<DOCNO> 121998 </DOCNO>
Cepheid Mass-Luminosity Relations from the Magellanic Clouds


  The OGLE data base is used in conjunction with Kurucz atmosphere models to
generate sets of period, effective temperature and luminosity for fundamental
and overtone Magellanic Cloud Cepheids. The Florida pulsation code (with linear
turbulent convection) is then used to compute masses for these stars, assuming
an average composition of ($X$=0.716, $Z$=0.010) for the LMC and of ($X$=0.726,
$Z$=0.004) for the SMC. The average $M$--$L$ relation for the fundamental
Cepheids matches closely that for the first overtone Cepheids for each
Magellanic Cloud. Neither the SMC nor the LMC average $\Log M$--$\Log L$
relations are straight, but have a noticeable curvature.
  In view of the uncertainties in distance and reddening we have adopted three
different choices for these quantities. The results based on the 'long'
distance scale to the clouds give a better agreement between theory and and
observations than the 'short' one.
  All the current evolutionary tracks predict systematically larger masses for
given luminosities than our observationally derived ones, especially at the
high end. Moreover, our study confirms that the evolutionary tracks of the low
mass stars in SMC are not in agreement with the observations as they do not
extend sufficiently blueward and do not penetrate deep enough into the
instability strip, or not at all.
  The inference of masses directly from the observational database yields a
novel and strong constraint on evolutionary calculations.

</DOC>
<DOC>
<DOCNO> 13379 </DOCNO>
Acetylene on Si(100) from first principles: adsorption geometries,


  Adsorption of acetylene on Si(100) is studied from first principles. We find
that, among a number of possible adsorption configurations, the lowest-energy
structure is a ``bridge'' configuration, where the C$_2$H$_2$ molecule is
bonded to two Si atoms. Instead, ``pedestal'' configurations, recently proposed
as the lowest-energy structures, are found to be much higher in energy and,
therefore, can represent only metastable adsorption sites. We have calculated
the surface formation energies for two different saturation coverages, namely
0.5 and 1 monolayer, both observed in experiments. We find that although, in
general, the full monolayer coverage is favored, a narrow range of temperatures
exists in which the 0.5 monolayer coverage is the most stable one, where the
acetylene molecules are adsorbed in a $2\times 2$ structure. This result
disagrees with the conclusions of a recent study and represents a possible
explanation of apparently controversial experimental findings. The crucial role
played by the use of a gradient-corrected density functional is discussed.
Finally, we study thermal decomposition of acetylene adsorbed on Si(100) by
means of finite-temperature Molecular Dynamics, and we observe an unexpected
behavior of dehydrogenated acetylene molecules.

</DOC>
<DOC>
<DOCNO> 11752 </DOCNO>
Critical Behavior of a Three-State Potts Model on a Voronoi Lattice


  We use the single-histogram technique to study the critical behavior of the
three-state Potts model on a (random) Voronoi-Delaunay lattice with size
ranging from 250 to 8000 sites. We consider the effect of an exponential decay
of the interactions with the distance,$J(r)=J_0\exp(-ar)$, with $a>0$, and
observe that this system seems to have critical exponents $\gamma$ and $\nu$
which are different from the respective exponents of the three-state Potts
model on a regular square lattice. However, the ratio $\gamma/\nu$ remains
essentially the same. We find numerical evidences (although not conclusive, due
to the small range of system size) that the specific heat on this random system
behaves as a power-law for $a=0$ and as a logarithmic divergence for $a=0.5$
and $a=1.0$

</DOC>
<DOC>
<DOCNO> 121445 </DOCNO>
The Old Halo metallicity gradient: the trace of a self-enrichment


  Based on a model of globular cluster self-enrichment published in a previous
paper, we present an explanation for the metallicity gradient observed
throughout the galactic Old Halo. Our self-enrichment model is based on the
ability of globular cluster progenitor clouds to retain the ejecta of a first
generation of Type II Supernovae. The key point is that this ability depends on
the pressure exerted on the progenitor cloud by the surrounding protogalactic
medium and therefore on the location of the cloud in the protoGalaxy. Since
there is no significant (if any) metallicity gradient in the whole halo, we
also present a review in favour of a galactic halo partly build via accretions
and mergers of satellite systems. Some of them bear their own globular clusters
and therefore ``contaminate'' the system of globular clusters formed ``in
situ'', namely within the original potential well of the Galaxy. Therefore, the
comparison between our self-enrichment model and the observational data should
be limited to the genuine galactic globular clusters, the so-called Old Halo
group.

</DOC>
<DOC>
<DOCNO> 119709 </DOCNO>
Models for the interpretation of CaT and the blue Spectral Indices in


  We present a grid of theoretical models where the calculation of absorption
line spectral indices in both the blue and red wavelength ranges is done with
the same evolutionary synthesis code. We have computed some of these indices:
CaT, NaI, MgI in the near infrared and Mgb, Mg2, Fe52, Fe53, NaD and Hbeta, in
the blue-visible range, for Single Stellar Population (SSP) of 6 different
metallicities, (Z=0.0004,0.001, 0.004, 0.008, 0.02 and 0.05), and ages from 4
Myr to 20 Gyr.
  From the comparison of these evolutionary synthesis models with a compilation
of elliptical galaxy data from the literature, we find that the observed CaT
index follows the blue <Fe> index rather than Mg2 as the models predict. If
this implies an over-abundance [Mg/Ca] and we take into account the masses of
stars which produce Mg and Ca, these stars could form in a time scale shorter
than 5 Myr from the beginning of the star formation process. Alternatively, an
IMF biased towards very massive stars (M > 40 Msun) at the early epoch of star
formation in elliptical nuclei has to be assumed. We also suggest to revise the
calculation of the nucleosynthesis yield of Magnesium.
  By using the diagnostic diagram CaT-Hbeta to disentangle age and metallicity
in such populations, we obtain around solar abundances and a sequence of ages
between 4 and 16 Gyr for the galaxy sample.

</DOC>
<DOC>
<DOCNO> 8804 </DOCNO>
Shear-induced vortex decoupling in Bi2Sr2CaCu2O8 crystals


  Simultaneous transport and magnetization studies in Bi2Sr2CaCu2O8 crystals at
elevated currents reveal large discrepancies, including finite resistivity at
temperatures of 40K below the magnetic irreversibility line. This resistivity,
measured at the top surface, is non-monotonic in temperature and extremely
non-linear. The vortex velocity derived from magnetization is six orders of
magnitude lower than the velocity derived from simultaneous transport
measurements. The new findings are ascribed to a shear-induced decoupling, in
which the pancake vortices flow only in the top few CuO2 planes, and are
decoupled from the pinned vortices in the rest of the crystal.

</DOC>
<DOC>
<DOCNO> 120503 </DOCNO>
Effective cosmological "constant " and quintessence


  In this paper we present exactly solved extended quintessence models;
furthermore, through a dynamical effective Q-cosmological "constant", we
recover some of the L decaying cases found in the literature. Finally we
introduce a sort of complementarity between the Q-dominated or L-dominated
expansions of the Universe.

</DOC>
<DOC>
<DOCNO> 121372 </DOCNO>
The Galactic Disk Distribution of Planetary Nebulae With Warm Dust


  We investigate the galactic disk distribution of a sample of planetary
nebulae characterised in terms of their mid-infrared spectral features. The
total number of galactic disk PNe with 8-13mum spectra is brought up to 74 with
the inclusion of 24 new objects, whose spectra we present for the first time.
54 PNe have clearly identified warm dust emission features, and form a sample
which we use to construct the distribution of the C/O chemical balance in
galactic disk PNe. The dust emission features complement the information on the
progenitor masses brought by the gas-phase N/O ratios: PNe with unidentified
infrared emission bands have the highest N/O ratios, while PNe with the
silicate signature have either very high N enrichment or close to none, and SiC
emission features coincide with a range of moderate N-enrichments. We find a
trend for a decreasing proportion of O-rich PNe towards the third and fourth
galactic quadrants. Two independent distance scales confirmed that the
proportion of O-rich PNe decreases from 30+-9% inside the solar circle, to
14+-7% outside. PNe with warm dust are also the youngest. PNe with no warm dust
are uniformly distributed in C/O and N/O ratios, and do not appear to be
confined to C/O~1. They also have higher 6cm fluxes, as expected from more
evolved PNe. We show that the IRAS fluxes are a good representation of the
bolometric flux for warm-dust PNe. The requirement F(12um)>0.5Jy should probe a
good portion of the galactic disk, and the dominant selection effects are
rooted in the PN catalogues.

</DOC>
<DOC>
<DOCNO> 99653 </DOCNO>
On the homotopy theory of arrangements, II


  In "On the homotopy theory of arrangements," published in 1986, the authors
gave a comprehensive survey of the subject. This article updates and continues
the earlier article, noting some key open problems.

</DOC>
<DOC>
<DOCNO> 150686 </DOCNO>
Embedding Branes in Flat Two-time Spaces


  We show how non-near horizon, non-dilatonic $p$-brane theories can be
obtained from two embedding constraints in a flat higher dimensional space with
2 time directions. In particular this includes the construction of D3 branes
from a flat 12-dimensional action, and M2 and M5 branes from 13 dimensions. The
worldvolume actions are found in terms of fields defined in the embedding
space, with the constraints enforced by Lagrange multipliers.

</DOC>
<DOC>
<DOCNO> 71344 </DOCNO>
Reply to the Comment by U. Jentschura and E. Weniger


  It is shown that the criticism (revised version) made in hep-th/0007108 (by
Jentschura and Weniger) on hep-th/0006057 has no valid ground. Furthemore we
emphasize that the concept of the electric-magnetic duality used in the
analysis of QED one-loop effective action in physics/0010038 (by Jentschura)
has first been introduced in hep-th/0006057.

</DOC>
<DOC>
<DOCNO> 10157 </DOCNO>
Chaining in Magnetic Colloids in the Presence of Flow


  We discuss the effect of an homogeneous flow in the aggregation process of
colloidal magnetic particles at moderate concentration. Situations in which the
presence of flow acts in favor of the chaining process: particles assemble into
chains larger than the ones emerging in the absence of flow, under the only
influence of an externnaly imposed field, have been analyzed. The results we
obtain follow from the analysis of the pair correlation function which, owing
to the potencial character of the flow we consider, can be interpreted in terms
of a Boltzmann-like stationary distribution function. To render the influence
of the flow on the resulting structures explicit, we study the particular cases
of axisymmetric and planar elongational flows.

</DOC>
<DOC>
<DOCNO> 119072 </DOCNO>
The Absolute Abundance of Iron in the Solar Corona


  We present a measurement of the abundance of Fe relative to H in the solar
corona using a technique which differs from previous spectroscopic and solar
wind measurements. Our method combines EUV line data from the CDS spectrometer
on SOHO with thermal bremsstrahlung radio data from the VLA. The coronal Fe
abundance is derived by equating the thermal bremsstrahlung radio emission
calculated from the EUV Fe line data to that observed with the VLA, treating
the Fe/H abundance as the sole unknown. We apply this technique to a compact
cool active region and find Fe/H
 = 1.56 x 10^{-4}, or about 4 times its value in the solar photosphere.
Uncertainties in the CDS radiometric calibration, the VLA intensity
measurements, the atomic parameters, and the assumptions made in the spectral
analysis yield net uncertainties of order 20%. This result implies that low
first ionization potential elements such as Fe are enhanced in the solar corona
relative to photospheric values.

</DOC>
<DOC>
<DOCNO> 117627 </DOCNO>
Theory of "Jitter" Radiation from Small-Scale Random Magnetic Fields and


  Abridged.-- We demonstrate that the radiation emitted by ultrarelativistic
electrons in highly nonuniform, small-scale magnetic fields is different from
synchrotron radiation if the electron's transverse deflections in these fields
are much smaller than the beaming angle. A quantitative analytical theory of
this radiation, which we refer to as jitter radiation, is developed. It is
shown that the emergent spectrum is determined by statistical properties of the
magnetic field. As an example,we then use the model of a magnetic field in
internal shocks of GRBs. The spectral power distribution of radiation produced
by the power-law electrons is well described by a sharply broken power-law with
indices 1 and -(p-1)/2 and the jitter break frequency is independent of the
field strength but depends on the electron density in the ejecta. Since
large-scale fields may also be present in the ejecta, we construct a
two-component, jitter+synchrotron spectral model of the prompt $\gamma$-ray
emission. Quite surprisingly, this model seems to be readily capable of
explaining several properties of time-resolved spectra of some GRBs, such as
(i) the violation of the constraint on the low-energy spectral index called the
synchrotron ``line of death'', (ii) the sharp spectral break at the peak
frequency, inconsistent with the broad synchrotron bump, (iii) the evidence for
two spectral sub-components, and (iv) possible existence of emission features
called ``GRB lines''. We believe these facts strongly support both the
existence of small-scale magnetic fields and the proposed radiation mechanism
from GRB shocks. As an example, we use the composite model to analyze GRB
910503 which has two spectral peaks.

</DOC>
<DOC>
<DOCNO> 13965 </DOCNO>
Phonons and Forces: Momentum versus Pseudomomentum in Moving Fluids


  I provide a pedagogical introduction to the notion of pseudomomentum for
waves in a medium, and show how changes in pseudomomentum may sometimes be used
to compute real forces. I then explain how these ideas apply to sound waves in
a fluid. When the background fluid is in motion, the conservation laws for
pseudomomentum and pseudoenergy are most easily obtained by exploiting the
acoustic metric and the formalism of general relativity.

</DOC>
<DOC>
<DOCNO> 121611 </DOCNO>
Profiles and Polarization Properties of Emission Lines from Relativistic


  We examined the profiles and polarization properties of emission lines
originating from the extremely relativistic region of Kepler disks.
 Because the emission region is more localized to the inner part, e.g., a few
times the black hole radius, the profiles, and polarization properties are
remarkably modified. The black hole spin significantly affects the properties
through the inner edge. This observation, in spite of the technical
difficulties, provides an important diagnostic of the relativistic region.

</DOC>
<DOC>
<DOCNO> 13268 </DOCNO>
Comment on ``A Comparison Between Broad Histogram and Multicanonical


  A recent paper by A. R. Lima, P. M. C. de Oliveira, and T. J. P. Penna
[cond-mat/0002176; J. Stat. Phys. 99:691 (2000)], seems to contain at least two
mistakes which deserve comment, one concerning the numerical data, the other
being of a conceptual kind.

</DOC>
<DOC>
<DOCNO> 122008 </DOCNO>
An Imaging and Spectroscopic Study of the z=3.38639 Damped Lyman Alpha


  We present the results of a series of imaging and spectroscopic observations
aimed at identifying and studying the galaxy responsible for the z = 3.38639
damped lya system in the z = 3.61 QSO Q0201+1120. We find that the DLA is part
of a concentration of matter which includes at least four galaxies (probably
many more) over linear comoving dimensions, greater than 5h^-1Mpc. The absorber
may be a 0.7 L* galaxy at an impact parameter of 15 h^-1 kpc, but follow-up
spectroscopy is still required for positive identification. The gas is
turbulent, with many absorption components distributed over approximately 270
km/s and a large spin temperature, T_s greater than 4000K. The metallicity is
relatively high for this redshift, Z(DLA) approximately 1/20 Z(solar). From
consideration of the relative ratios of elements which have different
nucleosynthetic timescales, it would appear that the last major episode of star
formation in this DLA occurred at z greater than 4.3, more than approximately
 500 Myr prior to the time when we observe it.

</DOC>
<DOC>
<DOCNO> 69157 </DOCNO>
Magnetic lensing of extremely high energy cosmic rays in a galactic wind


  We show that in the model of Galactic magnetic wind recently proposed to
explain the extremely high energy (EHE) cosmic rays so far observed as
originating from a single source (M87 in the Virgo cluster), the magnetic field
strongly magnifies the fluxes and produces multiple images of the source. The
apparent position on Earth of the principal image moves, for decreasing
energies, towards the galactic south. It is typically amplified by an order of
magnitude at $E/Z\sim 2\times 10^{20}$ eV, but becomes strongly demagnified
below $10^{20}$ eV. At energies below $E/Z\sim 1.3\times 10^{20}$ eV, all
events in the northern galactic hemisphere are due to secondary images, which
have huge amplifications ($>10^2$). This model would imply strong asymmetries
between the north and south galactic hemispheres, such as a (latitude
dependent) upper cut-off value below $2\times 10^{20}$ eV for CR protons
arriving to the south and lower fluxes in the south than in the north above
$10^{20}$ eV. The large resulting magnifications reduce the power requirements
on the source, but the model needs a significant tunning between the direction
to the source and the symmetry axis of the wind. If more modest magnetic field
strengths were assumed, a scenario in which the observed EHE events are heavier
nuclei whose flux is strongly lensed becomes also plausible and would predict
that a transition from a light composition to a heavier one could take place at
the highest energies.

</DOC>
<DOC>
<DOCNO> 13708 </DOCNO>
Comment on ''Alternating spin and orbital dimerization and spin-gap


  By this Comment we would like to point out [2] that, though such
consideration can be quite sophisticated, the consideration of a
spin-pseudo-spin Hamiltonian has nothing in common with the reality. It means
that such the consideration are useless as far as the properties of real
systems are concerned.

</DOC>
<DOC>
<DOCNO> 102091 </DOCNO>
Lagrangian Matroids associated with Maps on Orientable Surfaces


  The aim of the paper is to clarify the nature of combinatorial structures
associated with maps on closed compact surfaces. We prove that maps give rise
to Lagrangian matroids representable in a setting provided by cohomology of the
surface with punctured points. Our proof is very elementary.
  We further observe that the greedy algorithm has a natural interpretation in
this setting, as a `peeling' procedure which cuts the (connected) surface into
a closed ring-shaped peel, and that this procedure is local.

</DOC>
<DOC>
<DOCNO> 118188 </DOCNO>
The Nature of Associated Absorption and the UV-X-ray Connection in 3C


  We discuss new Hubble Space Telescope spectroscopy of the radio-loud quasar,
3C 288.1. The data cover ~590 A to ~1610 A in the quasar rest frame. They
reveal a wealth of associated absorption lines (AALs) with no accompanying
Lyman-limit absorption. The metallic AALs range in ionization from C III and N
III to Ne VIII and Mg X. We use these data and photoionization models to derive
the following properties of the AAL gas: 1) There are multiple ionization zones
within the AAL region, spanning a factor of at least ~50 in ionization
parameter. 2) The overall ionization is consistent with the ``warm'' X-ray
continuum absorbers measured in Seyfert 1 nuclei and other QSOs. However, 3)
the column densities implied by the AALs in 3C 288.1 are too low to produce
significant bound-free absorption at any UV-X-ray wavelengths. Substantial
X-ray absorption would require yet another zone, having a much higher
ionization or a much lower velocity dispersion than the main AAL region. 4) The
total hydrogen column density in the AAL gas is log N_H (cm-2)= 20.2. 5) The
metallicity is roughly half solar. 6) The AALs have deconvolved widths of ~900
km/s and their centroids are consistent with no shift from the quasar systemic
velocity (conservatively within +/-1000 km/s). 7) There are no direct
indicators of the absorber's location in our data, but the high ionization and
high metallicity both suggest a close physical relationship to the quasar/host
galaxy environment. Finally, the UV continuum shape gives no indication of a
``blue bump'' at higher energies. There is a distinct break of unknown origin
at ~1030 A, and the decline toward higher energies (with spectral index alpha =
-1.73, for f_nu ~ nu^alpha) is even steeper than a single power-law
interpolation from 1030 A to soft X-rays.

</DOC>
<DOC>
<DOCNO> 151175 </DOCNO>
Warping and vacua of $(S)YM_{3+1}$


  We use dielectric branes to find non singular string theory duals of a
perturbed 2+1 dimensional gauge theory living on D2 branes. By adding fermion
masses we obtain theories with reduced supersymmetry. The Higgs vacua of the
perturbed theory correspond to polarization of the D2 branes into D4 branes.
The confining vacua correspond to polarization of the D2 branes into NS5
branes. We consider different mass perturbations. Adding three equal masses
preserves N=2 supersymmetry. In this case there are no confining vacua. By
adding a fourth fermion mass we break all the supersymmetry, and find confining
vacua. We also obtain duals for domain walls, condensates, baryon vertices,
glueballs and flux tubes. We comment on the Kahler potentials for the Higgs and
confining phases. In the course of the calculations we also find a nontrivial
consistency check of the NS5 brane action in a D2 brane background.

</DOC>
<DOC>
<DOCNO> 170120 </DOCNO>
The interference of the nonclassical light pulse with a coherent one and


  Using the theoretical model of the optical beam-splitter, the interference of
the self-phase modulated ultrashort light pulse (SPM-USP) with the coherent one
is investigated. It is found that, the choice of the coefficient of
transmission of the beam-splitter allows one to get the spectra of quadrature
fluctuations with forms of interest to us. It is shown that the choice of the
geometrical phase gives one the control of the position of the ellipse of
squeezing in the quadrature space XY. The extended Mandel parameter is
introduced and the photon statistics is scanned at all frequencies. It is
established that the sub- and super-Poissonian statistics formation can be
determined by the choice of the nonlinear phase addition and initial linear
phase shift between pulses. It is also shown that the self-phase modulation
(SPM) leads to the additional modulation of total photon number at the outputs
of the beam-splitter.

</DOC>
<DOC>
<DOCNO> 100741 </DOCNO>
The theorem of Mather on generic projections for singular varieties


  The theorem of Mather on generic projections of smooth algebraic varieties is
also proved for the singular ones.

</DOC>
<DOC>
<DOCNO> 84453 </DOCNO>
The strong and weak holographic principles


  We review the different proposals which have so far been made for the
holographic principle and the related entropy bounds and classify them into the
strong, null and weak forms. These are analyzed, with the aim of discovering
which may hold at the level of the full quantum theory of gravity. We find that
only the weak forms, which constrain the information available to observers on
boundaries, are implied by arguments using the generalized second law. The
strong forms, which go further and posit a bound on the entropy in spacelike
regions bounded by surfaces, are found to suffer from serious problems, which
give rise to counterexamples already at the semiclassical level. The null form,
proposed by Fischler, Susskind, Bousso and others, in which the bound is on the
entropy of certain null surfaces, appears adequate at the level of a bound on
the entropy of matter in a single background spacetime, but attempts to include
the gravitational degrees of freedom encounter serious difficulties. Only the
weak form seems capable of holding in the full quantum theory.
  The conclusion is that the holographic principle is not a relationship
between two independent sets of concepts: bulk theories and measures of
geometry vrs boundary theories and measures of information. Instead, it is the
assertion that in a fundamental theory the first set of concepts must be
completely reduced to the second.

</DOC>
<DOC>
<DOCNO> 71599 </DOCNO>
Light Hadron Weak Matrix Elements


  I review this year's developments in the study of weak matrix elements of
light hadrons on the lattice, with emphasis on K^0-\bar K^0 mixing and K -> pi
pi decays.

</DOC>
<DOC>
<DOCNO> 119909 </DOCNO>
Origin of the high energy proton component below the geomagnetic cutoff


  The high flux proton component observed by AMS below the geomagnetic cutoff
can be well accounted for by assuming these particles to be secondaries
originating from the interaction of Cosmic Ray protons with the atmosphere.
Simulation results are reported

</DOC>
<DOC>
<DOCNO> 117307 </DOCNO>
Geodesic Lines in the Gravitational Field of Nonlinear Cosmic Strings


  We briefly review the equations of motion and the space-time interval due to
the nonlinear cosmic string that have been derived in ref. [3] for the first
time. The different types of isotropic and nonisotropic geodesic lines in the
gravitational field of nonlinear cosmic string have been analyzed in detail.

</DOC>
<DOC>
<DOCNO> 11039 </DOCNO>
Coexistence and Criticality in Size-Asymmetric Hard-Core Electrolytes


  Liquid-vapor coexistence curves and critical parameters for hard-core 1:1
electrolyte models with diameter ratios lambda = sigma_{-}/\sigma_{+}=1 to 5.7
have been studied by fine-discretization Monte Carlo methods. Normalizing via
the length scale sigma_{+-}=(sigma_{+} + sigma_{-})/2 relevant for the low
densities in question, both Tc* (=kB Tc sigma_{+-}/q^2 and rhoc* (= rhoc sigma
_{+-}^{3}) decrease rapidly (from ~ 0.05 to 0.03 and 0.08 to 0.04,
respectively) as lambda increases. These trends, which unequivocally contradict
current theories, are closely mirrored by results for tightly tethered dipolar
dimers (with Tc* lower by ~ 0-11% and rhoc* greater by 37-12%).

</DOC>
<DOC>
<DOCNO> 116667 </DOCNO>
A General Symbolic Method with Physical Applications


  A solution to the problem of unifying the General Relativistic and Quantum
Theoretical formalisms is given which introduces a new non-axiomatic symbolic
method and an algebraic generalization of the Calculus to non-finite symbolisms
without reference to the concept of a limit.
  An essential feature of the non-axiomatic method is the inadequacy of any
(finite) statements: Identifying this aspect of the theory with the "existence
of an external physical reality" both allows for the consistency of the method
with the results of experiments and avoids the so-called "measurement problem"
of quantum theory.

</DOC>
<DOC>
<DOCNO> 101963 </DOCNO>
Cohomology groups for projection point patterns


  Aperiodic point sets (or tilings) which can be obtained by the method of cut
and projection from higher dimensional periodic sets play an important role for
the description of quasicrystals. Their topological invariants can be computed
using the higher dimensional periodic structure. We report on the results
obtained for the cohomology groups of projection point patterns supplemented by
explicit calculations made by F. Gaehler for many well-known icosahedral
tilings.

</DOC>
<DOC>
<DOCNO> 117224 </DOCNO>
Wake and Impedance


  A systematic exposition of the basic concepts of wakes and impedances is
given for relativistic beams in accelerators.

</DOC>
<DOC>
<DOCNO> 117256 </DOCNO>
Approximate 3-Dimensional Electrical Impedance Imaging


  We discuss a new approach to three-dimensional electrical impedance imaging
based on a reduction of the information to be demanded from a reconstruction
algorithm. Images are obtained from a single measurement by suitably
simplifying the geometry of the measuring chamber and by restricting the nature
of the object to be imaged and the information required from the image. In
particular we seek to establish the existence or non-existence of a single
object (or a small number of objects) in a homogeneous background and the
location of the former in the (x,y)-plane defined by the measuring electrodes.
Given in addition the conductivity of the object rough estimates of its
position along the z-axis may be obtained. The approach may have practical
applications.

</DOC>
<DOC>
<DOCNO> 151219 </DOCNO>
Order 1/N^2 test of the Maldacena conjecture: Cancellation of the


  We test the Maldacena conjecture for type IIB String Theory/ N=4 Yang-Mills
by calculating the one-loop corrections in the bulk theory to the Weyl anomaly
of the boundary CFT when the latter is coupled to a Ricci-flat metric. The
contributions cancel within each supermultiplet, in agreement with the
conjecture.

</DOC>
<DOC>
<DOCNO> 102597 </DOCNO>
Simple algebras of Weyl type


  Over a field $F$ of any characteristic, for a commutative associative algebra
$A$ with an identity element and for the polynomial algebra $F[D]$ of a
commutative derivation subalgebra $D$ of $A$, the associative and the Lie
algebras of Weyl type on the same vector space $A[D]=A\otimes F[D]$ are
defined. It is proved that $A[D]$, as a Lie algebra (modular its center) or as
an associative algebra, is simple if and only if $A$ is $D$-simple and $A[D]$
acts faithfully on $A$. Thus a lot of simple algebras are obtained.

</DOC>
<DOC>
<DOCNO> 68911 </DOCNO>
An Effective Approach to VMD at One Loop Order and the Departures from


  We examine the mechanisms producing departures from ideal mixing for vector
mesons within the context of the Hidden Local Symmetry (HLS) model. We show
that kaon loop transitions between the ideal combinations of the $\omega$ and
$\phi$ mesons necessitate a field transformation in order to get the mass
eigenstates. It is shown that this transformation is close to a rotation for
processes involving, like meson decays, on--shell $\omega$ and $\phi$ mesons.
The HLS model predicts a momentum dependent, slowly varying mixing angle
between the ideal states. We examine numerically the consequences of this for
radiative and leptonic decays of light mesons. The mean $\omega-\phi$ mixing
angle is found smaller than its ideal value; this is exhibited separately in
radiative and in leptonic decays. Effects of nonet symmetry breaking in the
vector sector are compared to those produced by the field rotation implied by
the HLS model.

</DOC>
<DOC>
<DOCNO> 12186 </DOCNO>
Photoemission in the system of linear chains : application to


  Photoemission in the system of linear charged chains has been studied with
the dipole matrix incorporated, from which its dependencies on the
photoelectron momentum (${\bf k}$), photon polarization ($\hat{\bf E}$), and
photon energy ($\omega$) can be explored. The used model is the
three-dimensional array of noninteracting chains, which is so simple as to
allow an analytic approach. Motivations of the study are for the doped CuO$_3$
chain in PrBa$_2$Cu$_3$O$_7$ and the doped static stripe phase in La$_{\rm
2-x-y}$Nd$_{\rm y}$Sr$_{\rm x}$CuO$_4$. The one-dimensional dispersion
exhibiting spin-charge separation and its dependence on the momentum
perpendicular to the chain and its $\hat{\bf E}$-dependency as well are
discussed in PrBa$_2$Cu$_3$O$_7$. For La$_{\rm 2-x-y}$Nd$_{\rm y}$Sr$_{\rm
x}$CuO$_4$, the anomalous spectral distribution formed by two sets of stripes
perpendicular to each other is investigated. The geometric effects led to by
the dipole transition matrix including the interference of photocurrents from
different chains are found to change the simple one-dimensional feature
drastically. We find these changes are consistent with experiment for the chain
system PrBa$_2$Cu$_3$O$_7$, but less satisfactory for the stripe phase in
La$_{\rm 2-x-y}$Nd$_{\rm y}$Sr$_{\rm x}$CuO$_4$. This means that in the stripe
phase much two-dimensional characters still exist unlike the chain system.

</DOC>
<DOC>
<DOCNO> 12910 </DOCNO>
Generalized Thermostatistical Description of Intermittency and


  We describe a simple and accurate framework for modeling the statistical
behavior of both fully developed turbulence and short-term dynamics of
financial markets based on the formalism of Tsallis' generalized non-extensive
thermostatistics. Within this framework, we show that intermittency and
non-extensivity are naturally linked by the entropic parameter q. Our results,
concerning both probability density functions and structure functions exponents
are in very good agreement with experimental data.

</DOC>
<DOC>
<DOCNO> 116920 </DOCNO>
Simulation of Returning Electrons from a Klystron Collector


  Spurious oscillations in klystrons due to returning electrons from the
collector into the drift tube were observed and studied at KEK. Simulations of
returning electrons using EGS4 Monte Carlo method have been performed. And the
oscillation conditions are described in this paper.

</DOC>
<DOC>
<DOCNO> 69128 </DOCNO>
Global Fits to Electroweak Data Using GAPP


  At Run II of the Tevatron it will be possible to measure the W boson mass
with a relative precision of about 2 times 10^-4, which will eventually
represent the best measured observable beyond the input parameters of the SM.
Proper interpretation of such an ultrahigh precision measurement, either within
the SM or beyond, requires the meticulous implementation and control of higher
order radiative corrections. The FORTRAN package GAPP, described here, is
specifically designed to meet this need and to ensure the highest possible
degrees of accuracy, reliability, adaptability, and efficiency.

</DOC>
<DOC>
<DOCNO> 40096 </DOCNO>
Study of the $D^+_s \to \pi^- \pi^+ \pi^+$ decay and measurement of


  From a sample of 848 $\pm$ 44 $D_s^+ \to \pi^- \pi^+ \pi^+$ decays, we find
$\Gamma(D_s^+ \to \pi^- \pi^+ \pi^+) / \Gamma(D_s^+ \to \phi \pi^+) =
  0.245 \pm 0.028^{+0.019}_{-0.012} $. Using a Dalitz plot analysis of this
three body decay, we find significant contributions from the channels
$\rho^0(770)\pi^+$, $\rho^0(1450)\pi^+$, $f_0(980)\pi^+$, $f_2(1270)\pi^+$, and
$f_0(1370)\pi^+$. We present also the values obtained for masses and widths of
the resonances $f_0(980)$ and $f_0(1370)$.

</DOC>
<DOC>
<DOCNO> 99893 </DOCNO>
Relating the Connes-Kreimer and Grossman-Larson Hopf algebras built on


  We find a relation between two Hopf algebras built on rooted trees. The first
is the Connes-Kreimer Hopf algebra H_R which describes a certain type of
renormalization in quantum field theory; the second is the Grossman-Larson Hopf
algebra A introduced ten years ago by some "differential" and combinatorial
reasons. Roughly, the relation is the following: there exists a duality between
these two Hopf algebras. We study then two natural operators on A, inspired by
similar ones introduced by Connes and Kreimer for H_R.

</DOC>
<DOC>
<DOCNO> 119813 </DOCNO>
Iron K line Variability in the Low-Luminosity AGN NGC 4579


  We present results of new ASCA observations of the low-luminosity AGN (LLAGN)
NGC 4579 obtained on 1998 December 18 and 28, and we report on detection of
variability of an iron K emission line. The X-ray luminosities in the 2--10 keV
band for the two observations are nearly identical (LX $\approx$
2$\times10^{41}$ ergs/s), but they are $\sim$35% larger than that measured in
1995 July by Terashima et al. An Fe K emission line is detected at
$6.39\pm0.09$ keV (source rest frame) which is lower than the line energy
$6.73^{+0.13}_{-0.12}$ keV in the 1995 observation. If we fit the Fe lines with
a blend of two Gaussians centered at 6.39 keV and 6.73 keV, the intensity of
the 6.7 keV line decreases, while the intensity of the 6.4 keV line increases,
within an interval of 3.5 yr. This variability rules out thermal plasmas in the
host galaxy as the origin of the ionized Fe line in this LLAGN. The detection
and variability of the 6.4 keV line indicates that cold matter subtends a large
solid angle viewed from the nucleus and that it is located within $\sim1$ pc
from the nucleus. It could be identified with an optically thick standard
accretion disk. If this is the case, a standard accretion disk is present at
the Eddington ratio of $L_{\rm Bol}/L_{\rm Eddington} \sim 2\times10^{-3}$. A
broad disk-line profile is not clearly seen and the structure of the innermost
part of accretion disk remains unclear.

</DOC>
<DOC>
<DOCNO> 118999 </DOCNO>
Kinematic Evidence of Minor Mergers in Normal Sa Galaxies: NGC3626,


  BVRI and H-alpha imaging and long-slit optical spectroscopic data are
presented for four morphologically normal and relatively isolated Sa galaxies,
NGC3626, NGC3900, NGC4772 and NGC5854. VLA HI synthesis imaging is presented
for the first 3 objects. In all 4 galaxies, evidence of kinematic decoupling of
ionized gas components is found; the degree and circumstances of the distinct
kinematics vary from complete counterrotation of all of the gas from all of the
stars (NGC3626) to nuclear gas disks decoupled from the stars (NGC5854) to
anomalous velocity central gas components (NGC3900 and NGC4772). In the 3
objects mapped in HI, the neutral gas extends far beyond the optical radius,
R_HI/R_25 > 2. In general, the HI surface density is very low and the outer HI
is patchy and asymmetric or found in a distinct ring, exterior to the optical
edge. While the overall HI velocity fields are dominated by circular motions,
strong warps are suggested in the outer regions. Optical imaging is also
presented for NGC 4138 previously reported by Jore et al. (1996) to show
counterrotating stellar components. The multiwavelength evidence is interpreted
in terms of the kinematic "memory" of past minor mergers in objects that
otherwise exhibit no morphological signs of interaction.

</DOC>
<DOC>
<DOCNO> 116395 </DOCNO>
A fully {\it ab initio} potential curve of near-spectroscopic quality


  A benchmark study has been carried out on the ground-state potential curve of
the hydroxyl anion, OH^{-}, including detailed calibration of both the
1-particle and n-particle basis sets. The CCSD(T) basis set limit overestimates
$\omega_e$ by about 10 cm^{-1}, which is only remedied by inclusion of
connected quadruple excitations in the coupled cluster expansion --- or,
equivalently, the inclusion of the $2\pi$ orbitals in the active space of a
multireference calculation. Upon inclusion of scalar relativistic effects (-3
cm^{-1} on $\omega_e$), a potential curve of spectroscopic quality (sub-cm^{-1}
accuracy) is obtained. Our best computed EA(OH), 1.828 eV, agrees to three
decimal places with the best available experimental value. Our best computed
dissociation energies, D_0(OH^-)=4.7796 eV and D_0(OH)=4.4124 eV, suggest that
the experimental D_0(OH)=4.392 eV may possibly be about 0.02 eV too low.

</DOC>
<DOC>
<DOCNO> 101823 </DOCNO>
Exceptional groups and del Pezzo surfaces


  Given a del Pezzo surface of degree d between 1 and 6, possibly with rational
double points, we construct a "tautological" holomorphic G-bundle over X, where
G is a reductive group which is an appropriate conformal form of the simply
connected complex linear group whose coroot lattice is isomorphic to the
primitive cohomology of the minimal resolution of X. For example, in case d=3
and X is a smooth cubic surface, the rank 27 vector bundle over X associated to
the G-bundle constructed above and the standard 27-dimensional representation
of E_6 is a direct sum of the line bundles associated to the 27 lines on X. We
also discuss the restriction of the G-bundle to smooth hyperplane sections.

</DOC>
<DOC>
<DOCNO> 8292 </DOCNO>
Coulomb Blockade Oscillations in the Thermopower of Open Quantum Dots


  We consider Coulomb blockade oscillations of thermoelectric coefficients of a
single electron transistor based on a quantum dot strongly coupled to one of
the leads. Analytic expression for the thermopower as a function of temperature
$T$ and the reflection amplitude $r$ in the quantum point contact is obtained.
Two regimes can be identified: $T \ll E_C|r|^2$ and $T \gg E_C |r|^2$, where
$E_C$ is the charging energy of the dot. The former regime is characterized by
weak logarithmic dependence of the thermopower on the reflection coefficient,
in the latter the thermopower is linear in the reflection coefficient $|r|^2$
but depends on temperature only logarithmically.

</DOC>
<DOC>
<DOCNO> 99353 </DOCNO>
Serendipity: Spacetime Invariance and Scale Effect


  A logic of reciprocity between inertial frames in relative uniform motion is
investigated. Relativity allows any reference frame to apply Lorentz
Transformation while reciprocity would require the relative frame to use
Inverse Transformation for the same event, and vice versa. After such
transformations, an inseparability between relativistic measurements and the
covariant scale is examined. Scale conversion has been found to be necessary to
preserve spacetime invariance in Special Relativity. A new derivation of the
Lorentz Factor has been found based on the scale effect. The physical meaning
of the Factor is that it serves as a scale conversion ratio between relative
reference frames. Reciprocity in relativity and causality of covariance in
relative motion are thereby conserved. These logical conclusions harmonize
intrinsic natural invariances vis-a-vis apparent observational covariances.

</DOC>
<DOC>
<DOCNO> 68878 </DOCNO>
A consistent nonperturbative approach to thermal damping-rates


  We propose a nonperturbative scheme for the calculation of thermal
damping-rates using exact renormalization group (RG)-equations. Special
emphasis is put on the thermal RG where first results for the rate were given
in M. Pietroni, Phys. Rev. Lett. 81 (1998), 2424. We point out that in order to
obtain a complete result that also reproduces the known perturbative behaviour
one has to take into account effects that were neglected in the work cited
above. We propose a well-defined way of doing the calculations that reproduces
perturbation theory in lowest order but goes considerably beyond perturbative
results and should be applicable also at second order phase-transitions.

</DOC>
<DOC>
<DOCNO> 10263 </DOCNO>
Prospects for SIMPLE 2000: A large-mass, low-background Superheated


  SIMPLE 2000 (Superheated Instrument for Massive ParticLE searches) will
consist of an array of eight to sixteen large active mass ($\sim15$ g)
Superheated Droplet Detectors(SDDs) to be installed in the new underground
laboratory of Rustrel-Pays d'Apt. Several factors make of SDDs an attractive
approach for the detection of Weakly Interacting Massive Particles (WIMPs),
namely their intrinsic insensitivity to minimum ionizing particles, high
fluorine content, low cost and operation near ambient pressure and temperature.
We comment here on the fabrication, calibration and already-competitive first
limits from SIMPLE prototype SDDs, as well as on the expected immediate
increase in sensitivity of the program, which aims at an exposure of $>$25
kg-day during the year 2000. The ability of modest-mass fluorine-rich detectors
to explore regions of neutralino parameter space beyond the reach of the most
ambitious cryogenic projects is pointed out.

</DOC>
<DOC>
<DOCNO> 8982 </DOCNO>
Supercurrent noise in SNS junctions


  Quasiclassical Green's functions of a short superconductor/normal
metal/superconductor (SNS) junction are calculated for multi-mode junction with
arbitrary electron transmission properties. They provide the basis for
description of all of the junction transport characteristics, and are used to
calculate the equilibrium spectral density of supercurrent fluctuations.

</DOC>
<DOC>
<DOCNO> 69374 </DOCNO>
Soft gluon effects in the extraction of higher twists at large Bjorken x


  Existing data on the (unpolarised) transverse structure function of the
proton are analyzed for large values of the Bjorken variable x. The
leading-twist and a phenomenological higher-twist contributions are
simultaneously determined from a power correction analysis of the Nachtmann
moments for values of the squared four-momentum transfer between ~ 1 and 20
(GeV/c)**2. The results obtained adopting the next-to-leading order
approximation and those including the effects of soft gluon resummation are
compared. The sensitivity of the extraction of large-x higher twists to
high-order radiative corrections as well as to the value of alphas(MZ) is
illustrated.

</DOC>
<DOC>
<DOCNO> 39749 </DOCNO>
Spectroscopy and lifetime of bottom and charm hadrons


  We review recent experimental results on spectroscopy and lifetime of bottom
and charm hadrons.

</DOC>
<DOC>
<DOCNO> 69341 </DOCNO>
A Numerical Analysis to the {$\pi$} and {K} Coupled--Channel Scalar


  A numerical analysis to the scalar form-factor in the $\pi\pi$ and KK
coupled--channel system is made by solving the coupled-channel dispersive
integral equations, using the iteration method. The solutions are found not
unique. Physical application to the $\pi\pi$ central production in the $pp\to
pp\pi\pi$ process is discussed based upon the numerical solutions we found.

</DOC>
<DOC>
<DOCNO> 117680 </DOCNO>
Nanoarcsecond single-dish imaging of the Vela pulsar


  We have measured the properties of the diffractive scintillation toward the
Vela pulsar under the extremely strong scattering conditions encountered at 660
MHz. We obtain a decorrelation bandwidth of $\nu_d = 244 \pm 4$ Hz and
diffractive decorrelation timescale of $t_{\rm diff} = 3.3\pm 0.3$ s. Our
measurement of the modulation indices $m=0.87\pm 0.003\pm 0.05$ and $m=0.93\pm
0.03 \pm 0.05$ (one for each polarization stream), are at variance with the
modulation index of the Vela pulsar obtained at 2.3 GHz by Gwinn et al. (1997)
{\it if} the deviation from a modulation index of unity is ascribed to a source
size effect.

</DOC>
<DOC>
<DOCNO> 100826 </DOCNO>
Implicit Function Theorem for systems of polynomial equations with


  We study the existence problem for a local implicit function determined by a
system of nonlinear algebraic equations in the particular case when the
determinant of its Jacobian matrix vanishes at the point under consideration.
We present a system of sufficient conditions that implies existence of a local
implicit function as well as another system of sufficient conditions that
guarantees absence of a local implicit function. The results obtained are
applied to proving new and classical results on flexibility and rigidity of
polyhedra and frameworks.

</DOC>
<DOC>
<DOCNO> 101881 </DOCNO>
Test Function Space for Wick Power Series


  We derive a criterion that is convenient for applications and exactly
characterizes the test function space on which the operator realization of a
given series of Wick powers of a free field is possible. The suggested
derivation does not use the assumption that the metric of the state space is
positive and can therefore be used in a gauge theory. It is based on the
systematic use of the analytic properties of the Hilbert majorant of the
indefinite metric and on the application of a suitable theorem on the
unconditional convergence of series of boundary values of analytic functions.

</DOC>
<DOC>
<DOCNO> 84343 </DOCNO>
Coupling of Gravitation and Electromagnetism in the Weak Field


  Using the weak field approximation, we can express the theory of general
relativity in a Maxwell-type structure comparable to electromagnetism. We find
that every electromagnetic field is coupled to a gravitoelectric and
gravitomagnetic field. Acknowledging the fact that both fields originate from
the same source, the particle, we can express the magnetic and electric field
through their gravitational respective analogues using the proportionality
coefficient k. This coefficient depends on the ratio of mass and charge and the
ratio between the electromagnetic and gravitic-gravitomagnetic permittivity and
permeability respectively. Although the coefficient is very small, the fact
that electromagnetic fields in material media can be used to generate
gravitational and gravitomagnetic fields and vice versa is not commonly known.
We find that the coupling coefficient can be increased by massive ion currents,
electron and nuclear spin-alignment. Advances in material sciences, cryogenic
technology and high frequency electromagnetic fields in material media may lead
to applications of the derived relationships.

</DOC>
<DOC>
<DOCNO> 69756 </DOCNO>
Stable Q-balls from extra dimensions


  Given a bulk scalar field with sufficient self-interactions in a higher
dimensional spacetime, it is shown that the continuous symmetries in four
dimensions, induced by the topological structure of the compact manifold,
naturally lead to formation of stable nontopological solitons of Q-ball type.
The mass per unit charge inside the soliton is bounded by the size of the extra
dimensions, and it is thus stable with respect to decaying into excited levels
of all bulk fields, irrespective of their bulk masses. A familiar example is
the Standard Model in the bulk, where the Kaluza-Klein levels of the Higgs
boson form a stable Q-ball. These stable solitons are natural candidates for
the dark matter in the Universe.

</DOC>
<DOC>
<DOCNO> 9605 </DOCNO>
Crossover from the chiral to the standard universality classes in the


  The conductance of a quantum wire with off-diagonal disorder that preserves a
sublattice symmetry (the random hopping problem with chiral symmetry) is
considered. Transport at the band center is anomalous relative to the standard
problem of Anderson localization both in the diffusive and localized regimes.
In the diffusive regime, there is no weak-localization correction to the
conductance and universal conductance fluctuations are twice as large as in the
standard cases. Exponential localization occurs only for an even number of
transmission channels in which case the localization length does not depend on
whether time-reversal and spin rotation symmetry are present or not. For an odd
number of channels the conductance decays algebraically. Upon moving away from
the band center transport characteristics undergo a crossover to those of the
standard universality classes of Anderson localization. This crossover is
calculated in the diffusive regime.

</DOC>
<DOC>
<DOCNO> 68511 </DOCNO>
Photons, neutrinos and large compact space dimensions


  We compute the contribution of Kaluza-Klein graviton exchange to the cross
section for photon-neutrino scattering. Unlike the usual situation where the
virtual graviton exchange represents a small correction to a leading order
electroweak or strong amplitude, in this case the graviton contribution is of
the same order as the electroweak amplitude, or somewhat larger. Inclusion of
the graviton contribution is not sufficient to allow high energy neutrinos to
scatter from relic neutrinos in processes such as
$\nu\bar{\nu}\to\gamma\gamma$, but the photon-neutrino decoupling temperature
is substantially reduced.

</DOC>
<DOC>
<DOCNO> 152301 </DOCNO>
Two-dimensional gravitational anomalies, Schwinger terms and dispersion


  We are dealing with two-dimensional gravitational anomalies, specifically
with the Einstein anomaly and the Weyl anomaly, and we show that they are fully
determined by dispersion relations independent of any renormalization procedure
(or ultraviolet regularization). The origin of the anomalies is the existence
of a superconvergence sum rule for the imaginary part of the relevant
formfactor. In the zero mass limit the imaginary part of the formfactor
approaches a $\delta$-function singularity at zero momentum squared, exhibiting
in this way the infrared feature of the gravitational anomalies. We find an
equivalence between the dispersive approach and the dimensional regularization
procedure. The Schwinger terms appearing in the equal time commutators of the
energy momentum tensors can be calculated by the same dispersive method.
Although all computations are performed in two dimensions the method is
expected to work in higher dimensions too.

</DOC>
<DOC>
<DOCNO> 117012 </DOCNO>
Challenges in Affecting U.S. Attitudes Towards Space Science


  Space Science enjoys broad public support in the US. People say they follow
developments with interest, and that the programs are worth their cost. This
attitude seems to arise in part because of the intrinsic accessibility and
appeal of the subject matter. Yet at the same time the public is often
disturbingly ignorant about basic facts. In this article I summarize recent
survey results, including attitudes towards basic research, and also consider
some of the criticisms of the polling methods. I argue that the results imply
vigorous and innovative education and outreach programs can and should be made
even more effective -- but that the consequences of success for Space Science
research itself are not obvious. I outline two popular education programs which
address some of the new challenges facing Space Science outreach.

</DOC>
<DOC>
<DOCNO> 99538 </DOCNO>
On the Weyl tensor of a self-dual complex 4-manifold


  We study complex 4-manifolds with holomorphic self-dual conformal structures,
and we obtain an interpretation of the Weyl tensor of such a manifold as the
projective curvature of a field of cones on the ambitwistor space. In
particular, its vanishing is implied by the existence of some compact,
simply-connected, null-geodesics. We also relate the Cotton-York tensor of an
umbilic hypersurface to the Weyl tensor of the ambient. As a consequence, a
conformal 3-manifold or a self-dual 4-manifold admitting a rational curve as a
null-geodesic is conformally flat. We show that the projective structure of the
beta-surfaces of a self-dual manifold is flat.

</DOC>
<DOC>
<DOCNO> 13653 </DOCNO>
Surface-Directed Spinodal Decomposition in Binary Fluid Mixtures


  We consider the phase separation of binary fluids in contact with a surface
which is preferentially wetted by one of the components of the mixture. We
review the results available for this problem and present new numerical results
obtained using a mesoscopic-level simulation technique for the 3-dimensional
problem.

</DOC>
<DOC>
<DOCNO> 10559 </DOCNO>
Sporadic randomness, Maxwell's Demon and the Poincare' recurrence times


  In the case of fully chaotic systems the distribution of the
Poincare'recurrence times is an exponential whose decay rate is the
Kolmogorov-Sinai(KS) entropy.We address the discussion of the same problem, the
connection between dynamics and thermodynamics,in the case of sporadic
randomness,using the Manneville map as a prototype of this class of processes.
We explore the possibility of relating the distribution of Poincare' recurrence
times to `thermodynamics',in the sense of the KS entropy,also in the case of an
inverse power law. This is the dynamic property that Zaslavsly [Phys.Today(8),
39(1999)] finds to be responsible for a striking deviation from ordinary
statistical mechanics under the form of Maxwell's Demon effect. We show that
this way of estabi- lishing a connection between thermodynamics and dynamics is
valid only in the case of strong chaos. In the case of sporadic randomness,
resulting at long times in the Levy diffusion processes,the sensitivity to
initial conditions is initially an inverse pow erlaw,but it becomes exponential
in the long-time scale, whereas the distribution of Poincare times keeps its
inverse power law forever. We show that a nonextensive thermodynamics would
imply the Maxwell's Demon effect to be determined by memory and thus to be
temporary,in conflict with the dynamic approach to Levy statistics. The
adoption of heuristic arguments indicates that this effect,is possible, as a
form of genuine equilibrium,after completion of the process of memory erasure.

</DOC>
<DOC>
<DOCNO> 99279 </DOCNO>
On the Quasi-Hopf structure of deformed double Yangians


  We construct universal twists connecting the centrally extended double
Yangian DY(sl(2))_c with deformed double Yangians DY_r(sl(2))_c, thereby
establishing the quasi-Hopf structures of the latter.

</DOC>
<DOC>
<DOCNO> 169655 </DOCNO>
Separability and Fourier representations of density matrices


  Using the finite Fourier transform, we introduce a generalization of
Pauli-spin matrices for $d$-dimensional spaces, and the resulting set of
unitary matrices $S(d) $ is a basis for $d\times d$ matrices. If $N=d_{1}\times
d_{2}\times...\times d_{b}$ and $H^{[ N]}=\bigotimes H^{% [ d_{k}]}$, we give a
sufficient condition for separability of a density matrix $\rho $ relative to
the $H^{[ d_{k}]}$ in terms of the $L_{1}$ norm of the spin coefficients of
$\rho >.$ Since the spin representation depends on the form of the tensor
product, the theory applies to both full and partial separability on a given
space $H^{[ N]}$% . It follows from this result that for a prescribed form of
separability, there is always a neighborhood of the normalized identity in
which every density matrix is separable. We also show that for every prime $p$
and $n>1$ the generalized Werner density matrix $W^{[ p^{n}]}(s) $ is fully
separable if and only if $s\leq (1+p^{n-1}) ^{-1}$.

</DOC>
<DOC>
<DOCNO> 170449 </DOCNO>
Spin Distributions for Bipartite Quantum Systems


  We carryout a comparative study of spin distributions defined over the sphere
for bipartite quantum spin assemblies. We analyse Einstein-Podolsky-Rosen-Bohm
(EPRB) spin correlations in a spin-s singlet state using these distributions.
We observe that in the classical limit EPRB spin distributions turn out to be
delta functions, thus reflecting the perfect anticorrelation property of two
spin vectors associated with a spin-s singlet state.

</DOC>
<DOC>
<DOCNO> 170397 </DOCNO>
A puzzle in quantum dynamics


  The textbook treatment in that the wave function of a dynamical system is
expanded in an eigenfunction series is investigated. With help of an elementary
example and some mathematical theorems, it is revealed that in terms of solving
the time-dependent Schr\"odinger equation the treatment involves in divergence
trouble . The root reason behind the trouble is finally analyzed.

</DOC>
<DOC>
<DOCNO> 70442 </DOCNO>
Conformal Brane World and Cosmological Constant


  We consider a recently proposed setup where a codimension one brane is
embedded in the background of a smooth domain wall interpolating between AdS
and Minkowski minima. Since the volume of the transverse dimension is infinite,
bulk supersymmetry is intact even if brane supersymmetry is completely broken.
On the other hand, in this setup unbroken bulk supersymmetry is incompatible
with non-zero brane cosmological constant, so the former appears to protect the
latter. In this paper we point out that, to have a consistent coupling between
matter localized on the brane and bulk gravity, in this setup generically it
appears to be necessary that the brane world-volume theory be conformal. Thus,
unbroken bulk supersymmetry appears to actually protect not only the
cosmological constant but also conformal invariance on the brane.

</DOC>
<DOC>
<DOCNO> 8386 </DOCNO>
Analytic properties of the structure function for the one-dimensional


  The structure function $S(k;\beta)$ for the one-dimensional one-component
log-gas is the Fourier transform of the charge-charge, or equivalently the
density-density, correlation function. We show that for $|k| < {\rm min}
  (2\pi \rho, 2 \pi \rho \beta)$, $S(k;\beta)$ is simply related to an analytic
function $f(k;\beta)$ and this function satisfies the functional equation
$f(k;\beta) = f(-2k/\beta;4/\beta)$. It is conjectured that the coefficient of
$k^j$ in the power series expansion of $f(k;\beta)$ about $k=0$ is of the form
of a polynomial in $\beta/2$ of degree $j$ divided by $(\beta/2)^j$. The bulk
of the paper is concerned with calculating these polynomials explicitly up to
and including those of degree 9. It is remarked that the small $k$ expansion of
$S(k;\beta)$ for the two-dimensional one-component plasma shares some
properties in common with those of the one-dimensional one-component log-gas,
but these break down at order $k^8$.

</DOC>
<DOC>
<DOCNO> 13355 </DOCNO>
Charge transfer electrostatic model of compositional order in perovskite


  We introduce an electrostatic model including charge transfer, which is shown
to account for the observed B-site ordering in Pb-based perovskite alloys. The
model allows charge transfer between A-sites and is a generalization of
Bellaiche and Vanderbilt's purely electrostatic model. The large covalency of
Pb^{2+} compared to Ba^{2+} is modeled by an environment dependent effective
A-site charge. Monte Carlo simulations of this model successfully reproduce the
long range compositional order of both Pb-based and Ba-based complex
A(BB^{'}B^{''})O_3 perovskite alloys. The models are also extended to study
systems with A-site and B-site doping, such as
(Na_{1/2}La_{1/2})(Mg_{1/3}Nb_{2/3})O_3,
(Ba_{1-x}La_{x})(Mg_{(1+x)/3}Nb_{(2-x)/3})O_3 and
(Pb_{1-x}La_{x})(Mg_{(1+x)/3}Ta_{(2-x)/3})O_3. General trends are reproduced by
purely electrostatic interactions, and charge transfer effects indicate that
local structural relaxations can tip the balance between different B-site
orderings in Pb based materials.

</DOC>
<DOC>
<DOCNO> 118473 </DOCNO>
Kinematics of Metal-Poor Stars in the Galaxy. II. Proper Motions for a


  We present a revised catalog of 2106 Galactic stars, selected without
kinematic bias, and with available radial velocities, distance estimates, and
metal abundances in the range 0.0 <= [Fe/H] <= -4.0. This update of the Beers
and Sommer-Larsen (1995) catalog includes newly-derived homogeneous photometric
distance estimates, revised radial velocities for a number of stars with
recently obtained high-resolution spectra, and refined metallicities for stars
originally identified in the HK objective-prism survey (which account for
nearly half of the catalog) based on a recent re-calibration. A subset of 1258
stars in this catalog have available proper motions, based on measurements
obtained with the Hipparcos astrometry satellite, or taken from the updated
Astrographic Catalogue (AC 2000; second epoch positions from either the Hubble
Space Telescope Guide Star Catalog or the Tycho Catalogue), the Yale/San Juan
Southern Proper Motion (SPM) Catalog 2.0, and the Lick Northern Proper Motion
(NPM1) Catalog. Our present catalog includes 388 RR Lyrae variables (182 of
which are newly added), 38 variables of other types, and 1680 non-variables,
with distances in the range 0.1 to 40 kpc.

</DOC>
<DOC>
<DOCNO> 69943 </DOCNO>
New inflation in supergravity with a chaotic initial condition


  We propose a self-consistent scenario of new inflation in supergravity.
Chaotic inflation first takes place around the Planck scale, which solves the
longevity problem, namely, why the universe can live much beyond the Planck
time, and also gives an adequate initial condition for new inflation. Then, new
inflation lasts long enough to generate primordial fluctuations for the large
scale structure, which generally has a tilted spectrum with the spectral index
$n_{s} < 1$. The successive decay of the inflaton leads to the reheating
temperature low enough to avoid the overproduction of gravitinos in a wide
range of the gravitino mass.

</DOC>
<DOC>
<DOCNO> 40433 </DOCNO>
Study of $\tau$ Decays to Six Pions and Neutrino


  The $\tau$ decays to six-pion final states have been studied with the CLEO
detector at the Cornell Electron Storage Ring. The measured branching fractions
are ${\cal B}(\tau^-\to 2\pi^-\pi^+3\pi^0\nu_{\tau})=(2.2 \pm 0.3 \pm
0.4)\times 10^{-4}$ and ${\cal B}(\tau^-\to 3\pi^-2\pi^+\pi^0\nu_{\tau})=(1.7
\pm 0.2 \pm 0.2)\times 10^{-4}$. A search for substructure in these decays
shows that they are saturated by intermediate states with $\eta$ or $\omega$
mesons. We present the first observation of the decay $\tau^-\to
2\pi^-\pi^+\omega\nu_{\tau}$ and the branching fraction is measured to be $(1.2
\pm 0.2 \pm 0.1) \times 10^{-4}$. The measured branching fractions are in good
agreement with the isospin expectations but somewhat below the
Conserved-Vector-Current predictions.

</DOC>
<DOC>
<DOCNO> 69024 </DOCNO>
Neutrinos and Gauge Unification


  The approximate unification of gauge couplings is the best indirect evidence
for low-energy supersymmetry, although it is not perfect in its simplest
realizations. Given the experimental evidence for small non-zero neutrino
masses, it is plausible to extend the MSSM with three right-handed neutrino
chiral multiplets, with large Majorana masses below the unification scale, so
that a see-saw mechanism can be implemented. In this extended MSSM, the
unification prediction for the strong gauge coupling constant at M_Z can be
lowered by up to \sim 5%, bringing it closer to the experimental value at
1\sigma, therefore improving significantly the accuracy of gauge coupling
unification.

</DOC>
<DOC>
<DOCNO> 100915 </DOCNO>
Classification of Left-Covariant Differential Calculi on the Quantum


  For transcendental values of q the quantum tangent spaces of all
left-covariant first order differential calculi of dimension less than four on
the quantum group $\SLq 2$ are given. All such differential calculi $\Gamma $
are determined and investigated for which the left-invariant differential
one-forms $\omega (u^1_2)$, $\omega (u^2_1)$ and $\omega (u^1_1-u^2_2)$
generate $\Gamma $ as a bimodule and the universal higher order differential
calculus has the same dimension as in the classical case. Important properties
(cohomology spaces, *-structures, braidings, generalized Lie brackets) of these
calculi are examined as well.
  Keywords: quantum groups, noncommutative differential calculus, quantum
tangent space

</DOC>
<DOC>
<DOCNO> 169848 </DOCNO>
Generalized Noiseless Quantum Codes utilizing Quantum Enveloping


  A generalization of the results of Rasetti and Zanardi concerning avoiding
errors in quantum computers by using states preserved by evolution is
presented. The concept of the dynamical symmetry is generalized from the level
of classical Lie algebras and groups, to the level of a dynamical symmetry
based on quantum Lie algebras and quantum groups (in the sense of Woronowicz).
An intrinsic dependence of the concept of dynamical symmetry on the
differential calculus (which holds also in the classical case) is stressed. A
natural connection between quantum states invariant under a quantum group
action, and quantum states preserved by the dynamical evolution is discussed.

</DOC>
<DOC>
<DOCNO> 72306 </DOCNO>
Radiative-Recoil Corrections of Order $\alpha(Z\alpha)^5(m/M)m$ to Lamb


  The results and main steps of an analytic calculation of radiative-recoil
corrections of order $\alpha(Z\alpha)^5(m/M)m$ to the Lamb shift in hydrogen
are presented. The calculations are performed in the infrared safe Yennie
gauge. The discrepancy between two previous numerical calculations of these
corrections existing in the literature is resolved. Our new result eliminates
the largest source of the theoretical uncertainty in the magnitude of the
deuterium-hydrogen isotope shift.

</DOC>
<DOC>
<DOCNO> 83236 </DOCNO>
Verifying Termination of General Logic Programs with Concrete Queries


  We introduce a method of verifying termination of logic programs with respect
to concrete queries (instead of abstract query patterns). A necessary and
sufficient condition is established and an algorithm for automatic verification
is developed. In contrast to existing query pattern-based approaches, our
method has the following features: (1) It applies to all general logic programs
with non-floundering queries. (2) It is very easy to automate because it does
not need to search for a level mapping or a model, nor does it need to compute
an interargument relation based on additional mode or type information. (3) It
bridges termination analysis with loop checking, the two problems that have
been studied separately in the past despite their close technical relation with
each other.

</DOC>
<DOC>
<DOCNO> 70533 </DOCNO>
Heavy-to-light form factors: Symmetries at large recoil and calculation


  Recently it has been shown that in the large-recoil limit new symmetries
emerge which impose various relations on form factors that parametrise the
decay of heavy B mesons into light mesons. These symmetry relations are broken
by radiative QCD corrections. We show that these corrections are perturbatively
calculable, and present results to first order in the strong coupling constant
alpha_s.

</DOC>
<DOC>
<DOCNO> 69962 </DOCNO>
What is the Standard Model of Elementary Particles and Why We Have to


  We introduce the standard model of elementary particles and discuss the
reasons why we have to modify it. Emphasis is put on the indications from the
neutrinos and on the role of the Higgs particle; some promising theoretical
ideas, like quark-lepton symmetry, existence of super-heavy ``right-handed''
neutrinos, grand unification and supersymmetry at the weak scale, are
introduced and shortly discussed.

</DOC>
<DOC>
<DOCNO> 102587 </DOCNO>
Examples of Special Lagrangian Fibrations


  We explore a number of examples of special Lagrangian fibrations on
non-compact Calabi-Yau manifolds invariant under torus actions. These include
fibrations on crepant resolutions of canonical toric singularities (already
found by Goldstein), proper versions of these fibrations, and fibrations on
flat deformations of canonical toric singularities. We do this with an eye
towards understanding the global structure and discriminant loci of such
fibrations.
  The paper ends with some speculation, both about local mirror symmetry, and
the connections of this work with the work of W.D. Ruan and D. Joyce. In the
last section, we discuss the philosophy of the Strominger-Yau-Zaslow conjecture
in the light of a number of recent ideas of myself and Wilson, Kontsevich and
Soibelman, and Joyce.

</DOC>
<DOC>
<DOCNO> 12960 </DOCNO>
Probing Pores Using Elementary Quantum Mechanics


  The relaxation of polarized spins in a porous medium has been utilized as a
probe of its structure. We note that the governing diffusion problem has a
close parallel to that of a particle in a box, an elementary Quantum mechanics
toy model. Following the spirits of "free electron" model, we use generic
properties of the eigen spectrum to understand features common to a wide
variety of pore geometry, consistent with large scale numerical simulations and
experimental data.

</DOC>
<DOC>
<DOCNO> 119322 </DOCNO>
ISO detection of a 60micron source near GRB970508


  The Infrared Space Observatory observed the field of the $\gamma$--ray burst
GRB 970508 with the CAM and PHT instruments on May 21 and 24, 1997 and with PHT
in three filters in November 1997. A source at 60 $\mu$m (flux in May of $66\pm
10$ mJy) was detected near the position of the host galaxy of this
$\gamma$--ray burst. The source was detected again in November 1997, at a
marginally lower flux ($43\pm 13$ mJy). A Galactic cirrus origin and a stellar
origin for the emission can be ruled out on the basis of the infrared colours.
The marginal evidence for variability in the 60 $\mu$m flux between May and
November is not sufficient to warrant interpretation of the source as transient
fireball emission. However, the infrared colours are physically reasonable if
attributed to conventional dust emission from a single blackbody source. The
probability of detecting a 60 $\mu$m by chance in a PHT beam down to a
detection limit of 50 mJy is $\sim 5\times 10^{-3}$. If the source is at the
redshift of the host galaxy of the $\gamma$--ray burst the fluxes and upper
limits at wavelengths from 12 $\mu$m to 170 $\mu$m indicate it is an
ultraluminous infrared galaxy (L$_{\rm ir} \sim 2\times 10^{12}$ L$_{\sun}$).
The star formation rate is estimated to be several hundred solar masses per
year, depending significantly on model-dependent parameters. If this source is
associated with the host galaxy of GRB 970508, progenitor models which
associate GRBs with star-forming regions are favoured.

</DOC>
<DOC>
<DOCNO> 12554 </DOCNO>
Kondo Resonance in a Mesoscopic Ring Coupled to a Quantum Dot: Exact


  We study the persistent currents induced by both the Aharonov-Bohm and
Aharonov-Casher effects in a one-dimensional mesoscopic ring coupled to a
side-branch quantum dot at Kondo resonance. For privileged values of the
Aharonov-Bohm-Casher fluxes, the problem can be mapped onto an integrable
model, exactly solvable by a Bethe ansatz. In the case of a pure magnetic
Aharonov-Bohm flux, we find that the presence of the quantum dot has no effect
on the persistent current. In contrast, the Kondo resonance interferes with the
spin-dependent Aharonov-Casher effect to induce a current which, in the
strong-coupling limit, is independent of the number of electrons in the ring.

</DOC>
<DOC>
<DOCNO> 8761 </DOCNO>
Self-Organization in Space and Induced by Fluctuations


  We present a simple discrete model for the non-linear spatial interaction of
different kinds of ``subpopulations'' composed of identical moving entities
like particles, bacteria, individuals, etc. The model allows to mimic a variety
of self-organized agglomeration and segregation phenomena. By relating it to
game-theoretical ideas, it can be applied not only to attractive and repulsive
interactions in physical and chemical systems, but also to the much richer
combinations of positive and negative interactions found in biological and
socio-economic systems. Apart from investigating symmetric interactions related
to a continuous increase of the ``overall success'' within the system
(``self-optimization''), we will focus on cases, where fluctuations further or
induce self-organization, even though the initial conditions and the
interactions are assumed homogeneous in space (translation invariant).

</DOC>
<DOC>
<DOCNO> 71772 </DOCNO>
The Center symmetry and its spontaneous breakdown at high temperatures


  We examine the role of the center Z(N) of the gauge group SU(N) in gauge
theories. In this pedagogical article, we discuss, among other topics, the
center symmetry and confinement and deconfinement in gauge theories and
associated finite-temperature phase transitions. We also look at universal
properties of domain walls separating distinct confined and deconfined bulk
phases, including a description of how QCD color-flux strings can end on
color-neutral domain walls, and unusual finite-volume dependence in which
quarks in deconfined bulk phase seem to be "confined".

</DOC>
<DOC>
<DOCNO> 10292 </DOCNO>
A multifractal random walk


  We introduce a class of multifractal processes, referred to as Multifractal
Random Walks (MRWs). To our knowledge, it is the first multifractal processes
with continuous dilation invariance properties and stationary increments. MRWs
are very attractive alternative processes to classical cascade-like
multifractal models since they do not involve any particular scale ratio. The
MRWs are indexed by few parameters that are shown to control in a very direct
way the multifractal spectrum and the correlation structure of the increments.
We briefly explain how, in the same way, one can build stationary multifractal
processes or positive random measures.

</DOC>
<DOC>
<DOCNO> 8612 </DOCNO>
Collective excitations of a periodic Bose condensate in the Wannier


  We study the dispersion relation of the excitations of a dilute Bose-Einstein
condensate confined in a periodic optical potential and its Bloch oscillations
in an accelerated frame. The problem is reduced to one-dimensionality through a
renormalization of the s-wave scattering length and the solution of the
Bogolubov - de Gennes equations is formulated in terms of the appropriate
Wannier functions. Some exact properties of a periodic one-dimensional
condensate are easily demonstrated: (i) the lowest band at positive energy
refers to phase modulations of the condensate and has a linear dispersion
relation near the Brillouin zone centre; (ii) the higher bands arise from the
superposition of localized excitations with definite phase relationships; and
(iii) the wavenumber-dependent current under a constant force in the
semiclassical transport regime vanishes at the zone boundaries. Early results
by J. C. Slater [Phys. Rev. 87, 807 (1952)] on a soluble problem in electron
energy bands are used to specify the conditions under which the Wannier
functions may be approximated by on-site tight-binding orbitals of harmonic-
oscillator form. In this approximation the connections between the low-lying
excitations in a lattice and those in a harmonic well are easily visualized.
Analytic results are obtained in the tight-binding scheme and are illustrated
with simple numerical calculations for the dispersion relation and
semiclassical transport in the lowest energy band, at values of the system
parameters which are relevant to experiment.

</DOC>
<DOC>
<DOCNO> 116736 </DOCNO>
Classical Radiation Reaction Off-Shell Corrections to the Covariant


  It has been shown by Gupta and Padmanabhan that the radiation reaction force
of the Abraham-Lorentz-Dirac equation can be obtained by a coordinate
transformation from the inertial frame of an accelerating charged particle to
that of the laboratory. We show that the problem may be formulated in a flat
space of five dimensions, with five corresponding gauge fields in the framework
of the classical version of a fully gauge covariant form of the Stueckelberg-
Feynman-Schwinger covariant mechanics (the zero mode fields of the 0,1,2,3
components correspond to the Maxwell fields). Without additional constraints,
the particles and fields are not confined to their mass shells. We show that in
the mass-shell limit, the generalized Lorentz force obtained by means of the
retarded Green's functions for the five-dimensional field equations provides
the classical Abraham-Lorentz-Dirac radiation reaction terms (with renormalized
mass and charge). We also obtain general coupled equations for the orbit and
the off-shell dynamical mass during the evolution. The theory does not admit
radiation if the particle remains identically on-shell. The structure of the
equations implies that the mass-shell deviaiton is bounded when the external
field is removed.

</DOC>
<DOC>
<DOCNO> 69629 </DOCNO>
Nonrelativistic Quark Model Calculation of the S parameter


  A critical review is presented of the attempts to estimate the Strong
Interactions contributions to the parameter $S$ ($L_{10}$ in the QCD Chiral
Version). In particular it is discussed why the estimations done for
Technicolor are unreliable. $S$ is calculated for heavy doublets of
Techniquarks using the Nonrelativistic Quark Model and keeping $v\simeq 0.25$
TeV fixed. It is found that heavy Techniquarks decouple, so it is possible to
obtain values for $S$ in agreement with present experimental data.

</DOC>
<DOC>
<DOCNO> 10015 </DOCNO>
Density fluctuations and single-particle dynamics in liquid lithium


  The single-particle and collective dynamical properties of liquid lithium
have been evaluated at several thermodynamic states near the triple point. This
is performed within the framework of mode-coupling theory, using a
self-consistent scheme which, starting from the known static structure of the
liquid, allows the theoretical calculation of several dynamical properties.
Special attention is devoted to several aspects of the single-particle
dynamics, which are discussed as a function of the thermodynamic state. The
results are compared with those of Molecular Dynamics simulations and other
theoretical approaches.

</DOC>
<DOC>
<DOCNO> 10741 </DOCNO>
On Effect of Equilibrium Fluctuations on Superfluid Density in Layered


  We calculate suppression of inter- and intralayer superconducting currents
due to equilibrium phase fluctuations and find that, in contrast to a recent
prediction, the effect of thermal fluctuations cannot account for linear
temperature dependence of the superfluid density in high-Tc superconductors at
low temperatures. Quantum fluctuations are found to dominate over thermal
fluctuations at low temperatures due to hardening of their spectrum caused by
the Josephson plasma resonance. Near Tc sizeable thermal fluctuations are found
to suppress the critical current in the stack direction stronger, than in the
direction along the layers. Fluctuations of quasiparticle branch imbalance make
the spectral density of voltage fluctuations at small frequencies non zero, in
contrast to what may be expected from a naive interpretation of Nyquist
formula.

</DOC>
<DOC>
<DOCNO> 122706 </DOCNO>
Radio Observations of High Redshift Star Forming Galaxies


  I summarize recent results from radio observations of high redshift star
forming galaxies, discuss radio continuum emission as a measure of star
formation rate, and consider future capabilities at cm to IR wavelengths.

</DOC>
<DOC>
<DOCNO> 122360 </DOCNO>
Seyfert Galaxies with Circumnuclear/Nuclear Starbursts


  In this paper, we present our preliminary results on Seyfert galaxies with
circumnuclear/nuclear starburst(SB) activity. We have searched the recent
available literature and found 76 active galaxies with clear evidence of
nuclear SB activity, among which 16 are Seyfert 1s, 51 Seyfert 2s, and 9
LINERs. After studying the 51 Seyfert 2s, we find that those Seyfert 2s with
hidden Seyfert 1 nuclei, have similar Infrared-Radio properties as Seyfert 1
galaxies, and are different from "real" Seyfert 2s without a hidden Seyfert 1
nucleus. The later are similar to starburst galaxies.

</DOC>
<DOC>
<DOCNO> 151364 </DOCNO>
Fine-tuning and the Wilson renormalization group


  We use the Wilson renormalization group (RG) formulation to solve the
fine-tuning procedure needed in renormalization schemes breaking the gauge
symmetry. To illustrate this method we systematically compute the non-invariant
couplings of the ultraviolet action of the SU(2) pure Yang-Mills theory at
one-loop order.

</DOC>
<DOC>
<DOCNO> 101592 </DOCNO>
t-analogue of the q-characters of finite dimensional representations of


  Frenkel-Reshetikhin introduced $q$-characters of finite dimensional
representations of quantum affine algebras. We give a combinatorial 
algorithm to compute them for all simple modules. Our tool is $t$-analogue 
of the $q$-characters, which is similar to
Kazhdan-Lusztig polynomials, and our algorithm has a resemblance with their
definition.

</DOC>
<DOC>
<DOCNO> 11533 </DOCNO>
Superconducting current-phase relation in Nb/Au/(001)YBa2Cu3Ox


  We probe directly the superconducting current-phase relations (CPR) of
Nb/Au/(001) YBa2Cu3Ox heterojunctions prepared in epitaxial c-axis oriented
YBa2Cu3Ox (YBCO) thin films. The measurements are performed by a
single-junction interference experiment. Atomic Force Microscope observations
and estimations made from I-V characteristics confirm the c-axis current
transport. No deviation of the current-phase relation from a sinusoidal shape
has been found within the experimental accuracy. Possible reasons of the
absence of the second harmonic in the CPR due to a second order tunneling are
discussed.

</DOC>
<DOC>
<DOCNO> 8503 </DOCNO>
Disorder Induced Diffusive Transport In Ratchets


  The effects of quenched disorder on the overdamped motion of a driven
particle on a periodic, asymmetric potential is studied. While for the
unperturbed potential the transport is due to a regular drift, the quenched
disorder induces a significant additional chaotic ``diffusive'' motion. The
spatio-temporal evolution of the statistical ensemble is well described by a
Gaussian distribution, implying a chaotic transport in the presence of quenched
disorder.

</DOC>
<DOC>
<DOCNO> 123073 </DOCNO>
Gamma-Ray Pulsars: Models and Predictions


  Pulsed emission from gamma-ray pulsars originates inside the magnetosphere,
from radiation by charged particles accelerated near the magnetic poles or in
the outer gaps. In polar cap models, the high energy spectrum is cut off by
magnetic pair production above an energy that is dependent on the local
magnetic field strength. While most young pulsars with surface fields in the
range B = 10^{12} - 10^{13} G are expected to have high energy cutoffs around
several GeV, the gamma-ray spectra of old pulsars having lower surface fields
may extend to 50 GeV. Although the gamma-ray emission of older pulsars is
weaker, detecting pulsed emission at high energies from nearby sources would be
an important confirmation of polar cap models. Outer gap models predict more
gradual high-energy turnovers at around 10 GeV, but also predict an inverse
Compton component extending to TeV energies. Detection of pulsed TeV emission,
which would not survive attenuation at the polar caps, is thus an important
test of outer gap models. Next-generation gamma-ray telescopes sensitive to
GeV-TeV emission will provide critical tests of pulsar acceleration and
emission mechanisms.

</DOC>
<DOC>
<DOCNO> 70007 </DOCNO>
Vacuum fluctuations of \bar{q}q and values of low-energy constants


  We discuss the influence of the vacuum fluctuations of \bar{q}q pairs on
low-energy constants and condensates. The analysis of the Goldstone boson
masses and decay constants shows that the three-flavour condensate and some
low-energy constants are very sensitive to the value of L_6, which measures the
Zweig-rule violation in the scalar channel. A chiral sum rule based on
experimental data in this channel is used to constrain L_6, confirming a
significant decrease between the two- and the three-flavor condensates.

</DOC>
<DOC>
<DOCNO> 12823 </DOCNO>
$\kappa-(BEDT-TTF)_2X$ organic crystals: superconducting versus


  A Hubbard model at half-filling on an anisotropic triangular lattice has been
proposed as the minimal model to describe conducting layers of
$\kappa-(BEDT-TTF)_2X$ organic materials. The model interpolates between the
square lattice and decoupled chains. The $\kappa-(BEDT-TTF)_2X$ materials
present many similarities with cuprates, such as the presence of unconventional
metallic properties and the close proximity of superconducting and
antiferromagnetic phases. As in the cuprates, spin fluctuations are expected to
play a crucial role in the onset of superconductivity. We perform a
weak-coupling renormalization-group analysis to show that a superconducting
instability occurs. Frustration in the antiferromagnetic couplings, which
arises from the underlying geometrical arrangement of the lattice, breaks the
perfect nesting of the square lattice at half-filling. The spin-wave
instability is suppressed and a superconducting instability predominates. For
the isotropic triangular lattice, there are again signs of long-range magnetic
order, in agreement with studies at strong-coupling.

</DOC>
<DOC>
<DOCNO> 72222 </DOCNO>
Nuclear effects on the spin-dependent structure functions


  We address the question how the spin-dependent nucleon structure function
g1(x,Q**2) gets modified when the nucleon is bound inside a nucleus. We analyze
the influence of nuclear interactions using the delta-pion model, known to
describe well the unpolarized effect, and the free polarized parton
distributions. The results for the neutron in 3-He and proton in 3-H, 7-Li and
19-F are presented, showing significant changes in the parton spin
distributions and in their moments. Scattering processes off polarized 7-Li are
suggested which could justify these theoretical calculations and shed more
light on both nuclear spin structure and short distance QCD.

</DOC>
<DOC>
<DOCNO> 117104 </DOCNO>
Spin Relaxation Resonances Due to the Spin-Axis Interaction in Dense


  Resonances in the magnetic decoupling curves for the spin relaxation of dense
alkali-metal vapors prove that much of the relaxation is due to the spin-axis
interaction in triplet dimers. Initial estimates of the spin-axis coupling
coefficients for the dimers are 290 MHz for Rb; 2500 MHz for Cs.

</DOC>
<DOC>
<DOCNO> 152294 </DOCNO>
Aspects of Collapsing Cycles


  Much has been learned about string theory over the last few years by studying
properties of cycles and branes in a given background geometry. Here we discuss
three situations (quantum volume, attractor flows/D-brane stability, and
dynamical topology change) in which cycles in a Calabi-Yau background evolve
and/or degenerate in some manner, yielding various insights into aspects of
quantum geometry. Based in part on talk given at Strings 2000.

</DOC>
<DOC>
<DOCNO> 151605 </DOCNO>
Hidden Symmetries in Second Class Constrained Systems - Are New Fields


  For many systems with second class constraints, the question posed in the
title is answered in the negative. We prove this for a range of systems with
two second class constraints. After looking at two examples, we consider a
fairly general proof. It is shown that, to unravel gauge invariances in second
class constrained systems, it is sufficient to work in the original phase space
itself. Extension of the phase space by introducing new variables or fields is
not required.

</DOC>
<DOC>
<DOCNO> 100299 </DOCNO>
Contact systems and corank one involutive subdistributions


  We give necessary and sufficient geometric conditions for a distribution (or
a Pfaffian system) to be locally equivalent to the canonical contact system on
Jn(R,Rm), the space of n-jets of maps from R into Rm. We study the geometry of
that class of systems, in particular, the existence of corank one involutive
subdistributions. We also distinguish regular points, at which the system is
equivalent to the canonical contact system, and singular points, at which we
propose a new normal form that generalizes the canonical contact system on
Jn(R,Rm) in a way analogous to that how Kumpera-Ruiz normal form generalizes
the canonical contact system on Jn(R,R), which is also called Goursat normal
form.

</DOC>
<DOC>
<DOCNO> 69343 </DOCNO>
Higgs Mechanism and Bulk Gauge Boson Masses in the Randall-Sundrum Model


  Assuming the breaking of gauge symmetries by the Higgs mechanism, we consider
the associated bulk gauge boson masses in the Randall-Sundrum background. With
the Higgs field confined on the TeV-brane, the W and Z boson masses can
naturally be an order of magnitude smaller than their Kaluza-Klein excitation
masses. Current electroweak precision data requires the lowest excited state to
lie above about 30 TeV, with fermions on the TeV-brane. This bound is reduced
to about 10 TeV if the fermions reside sufficiently close to the Planck-brane.
Thus, some tuning of parameters is needed. We also discuss the bulk Higgs case,
where the bounds are an order of magnitude smaller.

</DOC>
<DOC>
<DOCNO> 85164 </DOCNO>
Non-dopplerian cosmological redshift parameters in a model of


  Possible effects are considered which would be caused by a hypothetical
superstrong interaction of photons or massive bodies with single gravitons of
the graviton background. If full cosmological redshift magnitudes are caused by
the interaction, then the luminosity distance in a flat non-expanding universe
as a function of redshift is very similar to the specific function which fits
supernova cosmology data by Riess et al. From another side, in this case every
massive body, slowly moving relatively to the background, would experience a
constant acceleration, proportional to the Hubble constant, of the same order
as a small additional acceleration of Pioneer 10, 11.

</DOC>
<DOC>
<DOCNO> 151298 </DOCNO>
Exact thresholds and instanton effects in D=3 string theories


  Three-dimensional string theories with 16 supersymmetries are believed to
possess a non-perturbative U-duality symmetry $SO(8,24,\Zint)$. By
covariantizing the heterotic one-loop amplitude under U-duality, we propose an
exact expression for the $(\partial \phi)^4$ amplitude, that reproduces known
perturbative limits. The weak-coupling expansion in either of the heterotic,
type II or type I descriptions exhibits the well-known instanton effects, plus
new contributions peculiar to three-dimensional theories, including the
Kaluza-Klein 5-brane, for which we extract the summation measure. This letter
is a post-scriptum to hepth/0001083.

</DOC>
<DOC>
<DOCNO> 100793 </DOCNO>
Compilation of relations for the antisymmetric tensors defined by the


  This paper attempts to provide a comprehensive compilation of results, many
new here, involving the invariant totally antisymmetric tensors (Omega tensors)
which define the Lie algebra cohomology cocycles of $su(n)$, and that play an
essential role in the optimal definition of Racah-Casimir operators of $su(n)$.
Since the Omega tensors occur naturally within the algebra of totally
antisymmetrised products of $\lambda$-matrices of $su(n)$, relations within
this algebra are studied in detail, and then employed to provide a powerful
means of deriving important Omega tensor/cocycle identities. The results
include formulas for the squares of all the Omega tensors of $su(n)$. Various
key derivations are given to illustrate the methods employed.

</DOC>
<DOC>
<DOCNO> 152367 </DOCNO>
Locally Localized Gravity


  We study the fluctuation spectrum of linearized gravity around non-fine-tuned
branes. We focus on the case of an AdS4 brane in AdS5. In this case, for small
cosmological constant, the warp factor near the brane is essentially that of a
Minkowski brane. However, far from the brane, the metric differs substantially.
The space includes the AdS5 boundary, so it has infinite volume. Nonetheless,
for sufficiently small AdS4 cosmological constant, there is a bound state
graviton in the theory, and four-dimensional gravity is reproduced. However, it
is a massive bound state that plays the role of the four-dimensional graviton.

</DOC>
<DOC>
<DOCNO> 10709 </DOCNO>
Dynamics of Entangled Polymeric Fluids in Two-roll Mill studied via


  We present an extensive experimental study of birefringence and
velocity-gradient components for a series of high molecular weight, flexible,
entangled polystyrene solutions subjected to transient start-up flows in a
co-rotating two-mill to several Weissenberg numbers. The time-dependent changes
in the polymer microstructure, as measured by a two-color flow birefringence
technique, is shown to be very distinctly coupled with the transient response
of the corresponding velocity-field, measured by a dynamic light scattering
technique. As expected, polymer deformations induce substantial modifications
from the Newtonian flow-field. As a result, measured values of both
velocity-gradient components as well as flow-type parameter reduce, thereby
drastically decreasing the extensional strength or measured Weissenberg number
at the stagnation-point relative to the velocity-field for a Newtonian fluid.
Although the impact of the dynamics of both polymer on flow and flow on polymer
are very complicated, their individual behaviors and the tight coupling between
them are shown to be invariant to the changes in polymer concentration and
molecular weight, provided that the number of entanglements per chain, $N_e$ is
held fixed. The dependence of the transient results on $N_e$ is very similar to
that found in the steady-state experiments on the same polymeric fluids
(Sanyal, Yavich, and Leal, manuscript in preparation, 2000). The results
presented in this paper are in close qualitative agreement with the recent
theoretical predictions (Remmelgas and Leal, J. Non-Newtonian Fluid Mech. {\bf
90}, 187, 2000) using a reptation-based vector model.

</DOC>
<DOC>
<DOCNO> 120702 </DOCNO>
Fun for Two


  We performed populations synthesis calculations of single stars and binaries
and show that binary evolution is extremely important for Galactic astronomy.
We review several binary evolution models and conclude that they give quite
different results. These differences can be understood from the assumptions
related to how mass is transfered in the binary systems. Most important are 1)
the fraction of mass that is accreted by the companion star during mass
transfer, 2) the amount of specific angular momentum which is carried away with
the mass that leaves the binary system.

</DOC>
<DOC>
<DOCNO> 13659 </DOCNO>
Semiclassical trace formulae using coherent states


  We derive semiclassical trace formulae including Gutzwiller's trace formula
using coherent states. This formulation has several advantages over the usual
coordinate-space formulation. Using a coherent-state basis makes it immediately
obvious that classical periodic orbits make separate contributions to the trace
of the quantum-mechanical time evolution operator. In addition, our approach is
manifestly canonically invariant at all stages, and leads to the simplest
possible derivation of Gutzwiller's formula.

</DOC>
<DOC>
<DOCNO> 11930 </DOCNO>
Metal-Insulator Transitions in Interacting Disordered Systems


  A brief review of metal-insulator transitions in three-dimensional doped
semiconductors, with emphasis on the "critical exponent puzzle"; and new
experimental findings that signal the possibility of an unexpected
metal-insulator transition in dilute two-dimensional systems, such as silicon
MOSFETs and GaAs/AlGaAs heterostructures.

</DOC>
<DOC>
<DOCNO> 71185 </DOCNO>
Lifetimes of the b-flavored baryons in the light-front quark model


  The calculation of lifetimes of heavy-flavored baryons in the light-front
quark model approach is briefly reviewed.

</DOC>
<DOC>
<DOCNO> 85614 </DOCNO>
Signature Change on the Brane


  We explore the possibility of having a good description of classical
signature change in the brane scenario.

</DOC>
<DOC>
<DOCNO> 152082 </DOCNO>
World-Volume Potentials on D-branes


  By evaluating string scattering amplitudes, we investigate various low energy
interactions for the massless scalars on a nonabelian Dirichlet brane. We
confirm the existence of couplings of closed string fields to the world-volume
scalars, involving commutators of the latter. Our results are consistent with
the recently proposed nonabelian world-volume actions for Dp-branes.

</DOC>
<DOC>
<DOCNO> 100611 </DOCNO>
Differential calculi on finite groups


  A brief review of bicovariant differential calculi on finite groups is given,
with some new developments on diffeomorphisms and integration. We illustrate
the general theory with the example of the nonabelian finite group S_3.

</DOC>
<DOC>
<DOCNO> 8790 </DOCNO>
Synchronization in populations of globally coupled oscillators with


  A model for synchronization of globally coupled phase oscillators including
``inertial'' effects is analyzed. In such a model, both oscillator frequencies
and phases evolve in time. Stationary solutions include incoherent
(unsynchronized) and synchronized states of the oscillator population. Assuming
a Lorentzian distribution of oscillator natural frequencies, $g(\Omega)$, both
larger inertia or larger frequency spread stabilize the incoherent solution,
thereby making harder to synchronize the population. In the limiting case
$g(\Omega)=\delta(\Omega)$, the critical coupling becomes independent of
inertia. A richer phenomenology is found for bimodal distributions. For
instance, inertial effects may destabilize incoherence, giving rise to
bifurcating synchronized standing wave states. Inertia tends to harden the
bifurcation from incoherence to synchronized states: at zero inertia, this
bifurcation is supercritical (soft), but it tends to become subcritical (hard)
as inertia increases. Nonlinear stability is investigated in the limit of high
natural frequencies.

</DOC>
<DOC>
<DOCNO> 8451 </DOCNO>
Vortex Pinning and Dynamics in Layerd Superconductors with Periodic


  We examine vortex dynamics and pinning in layered superconductors using
three-dimensional molecular dyanmics simulations of magnetically interacting
pancake vortices. Our model treats the magnetic interactions of the pancakes
exactly, with longe-range logarithmic interactions both within and between
planes. At the matching field the vortices are aligned with the pinning array.
As a function of tilt angle for the pinning arrays a series of commensuration
effects occur, seen as peaks in the critical current, due to pancakes finding a
favorable alignment.

</DOC>
<DOC>
<DOCNO> 178512 </DOCNO>
Pion-nucleon interaction in a covariant hadron-exchange model


  We develop a relativistic covariant and unitary description of the
pion-nucleon interaction in a hadron-exchange model. The model is based on the
solution of a dimensionally reduced (quasipotential) Bethe-Salpeter equation
for the partial-wave off-shell $\pi N$ scattering amplitudes with the potential
consisting of the field-theoretical $s$- and $u$-channel nucleon, Roper, Delta,
$D_{13}$, $S_{11}$ exchanges, and the $t$-channel $\rho$ and $\sigma$ meson
exchanges. The contributions of the spin-3/2 Delta and $D_{13}$ resonances are
treated within the Rarita-Schwinger formalism and different forms of the $\pi
N\Delta$ vertex are investigated. The free parameters of the model are fitted
to the $\pi N$ phase-shift data of the KH80 and SM95 partial-wave analyses in
the region up to 600 MeV pion kinetic energy. The resulting on-shell solution
provides a good description of the $\pi N$ scattering lengths, as well as the
energy behavior of the S, P, and D partial waves. The sensitivity of the phase
shifts on various model-dependent effects is examined.

</DOC>
<DOC>
<DOCNO> 9534 </DOCNO>
Entropy-vanishing transition and glassy dynamics in frustrated spins


  In an effort to understand the glass transition, the dynamics of a
non-randomly frustrated spin model has been analyzed. The phenomenology of the
spin model is similar to that of a supercooled liquid undergoing the glass
transition. The slow dynamics can be associated with the presence of extended
string-like structures which demarcate regions of fast spin flips. An
entropy-vanishing transition, with the string density as the order parameter,
is related to the observed glass transition in the spin model.

</DOC>
<DOC>
<DOCNO> 68574 </DOCNO>
Color Superconductivity in High Density Effective Theory


  In this talk, I discuss the recent development in color superconductivity in
terms of effective field theory. By investigating the Cooper pair gap equations
at high density, we see that the effective theory simplifies the gap analysis
very much, especially in finding the ground state, the precise form of the gap,
and the critical temperature. Furthermore, the effective theory enables us to
estimate the critical density for color superconductivity, which is found to be
around $230~{\rm MeV}$ in the hard-dense-loop approximation. Finally, I briefly
mention the low-lying spectra of color superconductor at high density.

</DOC>
<DOC>
<DOCNO> 70901 </DOCNO>
Neutrino Mixing from the CKM matrix in SUSY SO(10) \times U(2)_{F}


  We construct a realistic model based on SUSY SO(10) with U(2) flavor
symmetry. A set of symmetric mass textures give rise to very good predictions;
15 masses and 6 mixing angles are predicted by 11 parameters. Both the vacuum
oscillation and LOW solutions are favored for the solar neutrino problem.

</DOC>
<DOC>
<DOCNO> 152447 </DOCNO>
Topological quantum field theories


  Following my plenary lecture on ICMP2000 I review my results concerning two
closely related topics: topological quantum field theories and the problem of
quantization of gauge theories. I start with old results (first examples of
topological quantum field theories were constructed in my papers in late
seventies) and I come to some new results, that were not published yet.

</DOC>
<DOC>
<DOCNO> 119538 </DOCNO>
WD1953-011 - a magnetic white dwarf with peculiar field structure


  We present H-alpha spectra of the magnetic white dwarf star WD1953-011 which
confirm the presence of the broad Zeeman components corresponding to a field
strength of about 500kG found by Maxted & Marsh (1999). We also find that the
line profile is variable over a timescale of a day or less. The core of the
H-alpha line also shows a narrow Zeeman triplet corresponding to a field
strength of of about 100kG which appears to be almost constant in shape. These
observations suggest that the magnetic field on WD1953-011 has a complex
structure and that the star has a rotational period of hours or days which
causes the observed variability of the spectra. We argue that neither an offset
dipole model nor a double-dipole model are sufficient to explain our
observations. Instead, we propose a two component model consisting of a high
field region of magnetic field strength of about 500kG covering about 10% of
the surface area of the star superimposed on an underlying dipolar field of
mean field strength of about 70kG. Radial velocity measurements of the narrow
Zeeman triplet show that the radial velocity is constant to within a few km/s
so this star is unlikely to be a close binary.

</DOC>
<DOC>
<DOCNO> 9607 </DOCNO>
Charge-density-wave formation by Van Hove nesting in the \alpha-phase of


  We study the role of electron correlations in the formation of the surface
charge-density-wave state in the Sn/Ge(111) interface. The Fermi energy of the
overlayer is treated as a dynamical variable, which undergoes a substantial
renormalization by the interaction. We show that the Fermi level turns out to
be pinned to a Van Hove singularity in the density of states, which explains
the formation of the charge-density-wave, the observation of a very flat band
in photoemission experiments and the reduction of the spectral weight in the
low-temperature phase.

</DOC>
<DOC>
<DOCNO> 99916 </DOCNO>
Is it possible to reconstruct the freeze-out duration of heavy-ion


  We investigate what conditions allow us to extract the relative distribution
of freeze-out space and time points in an arbitrary reference frame using
tomography and source imaging. The source function may be extracted from the
two-particle correlation function measured in heavy-ion collisions using
imaging techniques. This imaged source function is related to the relative
distribution of freeze-out space and time points through a generalization of
the Radon transform found in tomography. Using tomography, the imaged source
function may be converted into the relative freeze-out distribution in the
frame of interest. We describe how the tomography may be performed in practice.

</DOC>
<DOC>
<DOCNO> 101161 </DOCNO>
On the relation of Manin's quantum plane and quantum Clifford algebras


  One particular approach to quantum groups (matrix pseudo groups) provides the
Manin quantum plane. Assuming an appropriate set of non-commuting variables
spanning linearly a representation space one is able to show that the
endomorphisms on that space preserving the non-commutative structure constitute
a quantum group. The non-commutativity of these variables provide an example of
non-commutative geometry.
  In some recent work we have shown that quantum Clifford algebras --i.e.
Clifford algebras of an arbitrary bilinear form-- are closely related to
deformed structures as q-spin groups, Hecke algebras, q-Young operators and
deformed tensor products. The natural question of relating Manin's approach to
quantum Clifford algebras is addressed here. Some peculiarities are outlined
and explicite computations using the Clifford Maple package are exhibited. The
meaning of non-commutative geometry is re-examined and interpreted in Clifford
algebraic terms.

</DOC>
<DOC>
<DOCNO> 101320 </DOCNO>
Recovery of a quarkonium system from experimental data


  For confining potentials of the form q(r)=r+p(r), where p(r) decays rapidly
and is smooth for r>0, it is proved that q(r) can be uniquely recovered from
the data {E_j,s_j}, where E_j are the bound states energies and s_j are the
values of u'_j(0), and u_j(r) are the normalized eigenfunctions of the problem
-u_j" +q(r)u_j=E_ju_j, r>0, u_j(0)=0, ||u_j||=1, where the norm is L^2(0,
\infty) norm. An algorithm is given for recovery of p(r) from few experimental
data.

</DOC>
<DOC>
<DOCNO> 12408 </DOCNO>
Intermediate spin, Schr\"odinger cat states and nano-magnets


  Quantum tunneling of nano-magnets finds a natural description in terms of
intermediate spin. Periodic magnetic effects correspond to a change of flux by
the flux quantum $\Phi_{0}$. Schr\"odinger cat states with different
superpositions of the applied magnetic field occur. The molecular magnet
Fe$_{8}$ is discussed and oscillations are predicted for Mn$_{12}$.

</DOC>
<DOC>
<DOCNO> 121605 </DOCNO>
VLT-detection of two edge-on Circumstellar Disks in the rho Oph dark


  Observations of the rho Ophiuchi star forming region with VLT ANTU and ISAAC
under 0.35" seeing conditions reveal two bipolar reflection nebulosities
intersected by central dust lanes. The sources (OphE-MM3 and CRBR 2422.8-3423)
can be identified as spatially resolved circumstellar disks viewed close to
edge-on, similar to edge-on disk sources discovered previously in the Taurus
and Orion star forming regions. Millimeter continuum fluxes yield disk masses
of the order of 0.01 Mo, i.e. about the mass deemed necessary for the minimum
solar nebula. Follow-up spectroscopic observations with SUBARU and CISCO show
that both disk sources exhibit featureless continua in the K-band. No accretion
or outflow signatures were detected. The slightly less edge-on orientation of
the disk around CRBR 2422.8-3423 compared to HH 30 leads to a dramatic
difference in the flux seen in the ISOCAM 4.5 mu to 12 mu bands. The
observations confirm theoretical predictions on the effect of disk geometry and
inclination angle on the spectral energy distribution of young stellar objects
with circumstellar disks.

</DOC>
<DOC>
<DOCNO> 80725 </DOCNO>
A gauge invariant study of the monopole condensation in non Abelian


  We investigate the Abelian monopole condensation in finite temperature SU(2)
and SU(3) pure lattice gauge theories. To this end we introduce a gauge
invariant disorder parameter built up in terms of the lattice Schr\"odinger
functional. Our numerical results show that the disorder parameter is different
from zero and Abelian monopole condense in the confined phase. On the other
hand our numerical data suggest that the disorder parameter tends to zero, in
the thermodynamic limit, when the gauge coupling constant approaches the
critical deconfinement value. In the case of SU(3) we also compare the
different kinds of Abelian monopoles which can be defined according to the
choice of the Abelian subgroups.

</DOC>
<DOC>
<DOCNO> 9306 </DOCNO>
Dissipative dynamics of vortex arrays in trapped Bose-condensed gases:


  We develop a theory of dissipative dynamics of large vortex arrays in trapped
Bose-condensed gases. We show that in a static trap the interaction of the
vortex array with thermal excitations leads to a non-exponential decay of the
vortex structure, and the characteristic lifetime depends on the initial
density of vortices. Drawing an analogy with physics of pulsar glitches, we
propose an experiment which employs the heating of the thermal cloud in the
course of the decay of the vortex array as a tool for a non-destructive study
of the vortex dynamics.

</DOC>
<DOC>
<DOCNO> 151068 </DOCNO>
Holographic duality, supersymmetry, and Painleve equation


  An example of the holographic correspondence between 2d, N=2 quantum field
theories and classical 4d, N=2 supergravity theories is found. The constraints
on the target space geometry of the 4d, N=2 non-linear sigma-models in N=2
supergravity background are interpreted as the renormalization flow equations
in two dimensions. Our geometrical description of the renormalization flow is
manifestly covariant under reparametrization of the 2d coupling constants. The
proposed holography is described in terms of the (Weyl) anti-self-dual Einstein
metrics, whose exact regular (Tod-Hitchin) solutions are governed by the
Painleve VI equation.

</DOC>
<DOC>
<DOCNO> 11036 </DOCNO>
Hybrid Monte Carlo algorithm for the Double Exchange Model


  The Hybrid Monte Carlo algorithm is adapted to the simulation of a system of
classical degrees of freedom coupled to non self-interacting lattices fermions.
The diagonalization of the Hamiltonian matrix is avoided by introducing a
path-integral formulation of the problem, in $d+1$ Euclidean space-time. A
perfect action formulation allows to work on the continuum euclidean time,
without need for a Trotter-Suzuki extrapolation. To demonstrate the feasibility
of the method we study the Double Exchange Model in three dimensions. The
complexity of the algorithm grows only as the system volume, allowing to
simulate in lattices as large as $16^3$ on a personal computer. We conclude
that the second order paramagnetic-ferromagnetic phase transition of Double
Exchange Materials close to half-filling belongs to the Universality Class of
the three-dimensional classical Heisenberg model.

</DOC>
<DOC>
<DOCNO> 8826 </DOCNO>
Mesoscopic phase separation in La2CuO4.02 - a 139La NQR study


  In crystals of La2CuO4.02 oxygen diffusion can be limited to such small
length scales, that the resulting phase separation is invisible for neutrons.
Decomposition of the 139La NQR spectra shows the existence of three different
regions, of which one orders antiferromagnetically below 17K concomitantly with
the onset of a weak superconductivity in the crystal. These regions are
compared to the macroscopic phases seen previously in the title compound and
the cluster-glass and striped phases reported for the underdoped Sr-doped
cuprates.

</DOC>
<DOC>
<DOCNO> 100956 </DOCNO>
Volume form as volume of infinitesimal simplices


  In the context of Synthetic Differential Geometry, we describe the square
volume of a ``second-infinitesimal simplex'', in terms of square-distance
between its vertices. The square-volume function thus described is symmetric in
the vertices. The square-volume gives rise to a characterization of the volume
form in the top dimension.

</DOC>
<DOC>
<DOCNO> 121268 </DOCNO>
Is it Round? Spectropolarimetry of the Type II-P Supernova 1999em


  We present the first multi-epoch spectropolarimetry of a type II plateau
supernova (SN II-P), with optical observations of SN 1999em on days 7, 40, 49,
159, and 163 after discovery. These data are used to probe the geometry of the
electron-scattering atmosphere before, during, and after the plateau phase,
which ended roughly 90 days after discovery. Weak continuum polarization with
an unchanging polarization angle (theta ~ 160 deg) is detected at all epochs,
with p ~ 0.2% on day 7, p ~ 0.3% on days 40 and 49, and p ~ 0.5% in the final
observations. Distinct polarization modulations across strong line features are
present on days 40, 49, 159, and 163. Uncorrected for interstellar polarization
(which is believed to be quite small), polarization peaks are associated with
strong P Cygni absorption troughs and nearly complete depolarization is seen
across the H-alpha emission profile. The temporal evolution of the continuum
polarization and sharp changes across lines indicate polarization intrinsic to
SN 1999em. When modeled in terms of the oblate, electron-scattering atmospheres
of Hoeflich, the observed polarization implies anasphericity of at least 7%
during the period studied. The temporal polarization increase may indicate
greater asphericity deeper into the ejecta. We discuss the implications of
asphericity on the use of type II-P supernovae as primary extragalactic
distance indicators through the expanding photosphere method (EPM). If
asphericity produces directionally dependant flux and peculiar galaxy motions
are characterized by sigma_v_rec = 300 km/s, it is shown that the agreement
between previous EPM measurements of SNe II and distances to the host galaxies
predicted by a linear Hubble law restrict mean SN II asphericity to values less
than 30% (3-sigma) during the photospheric phase.

</DOC>
<DOC>
<DOCNO> 7681 </DOCNO>
Resonances and Chaos in the Collective Oscillations of a Trapped Bose


  We investigate the collective oscillations of a Bose condensate in an
anisotropic harmonic trap. We analytically calculate the values of the trap
deformation for which the normal modes are in resonance. In presence of
low-order resonances, the amplitude dependence of frequencies is strongly
enhanced. We also study the transition to chaos of the collective modes as a
function of the trap anisotropy.

</DOC>
<DOC>
<DOCNO> 69693 </DOCNO>
Can cosmic strangelets reach the earth?


  The mechanism for the propagation of strangelets with low baryon number
through the atmosphere of the Earth has been explored. It has been shown that
under suitable initial conditions, such strangelets may indeed reach depths
near mountain altitudes with mass numbers and charges close to the observed
values in cosmic ray experiments.

</DOC>
<DOC>
<DOCNO> 100792 </DOCNO>
Equivariant Resolution of Points of Indeterminacy


  We prove an equivariant version of Hironaka's theorem on elimination of
points of indeterminacy. Our arguments rely on canonical resolution of
singularities.

</DOC>
<DOC>
<DOCNO> 8470 </DOCNO>
Andreev reflections and tunneling spectroscopy on underdoped NCCO (x =


  Andreev-reflection and tunneling studies have been carried out on a single
crystal of underdoped Nd1.85Ce0.15CuO4-d (NCCO) by using Ag, Pt-Ir and Nb tips
to clarify the symmetry of its order parameter. Surprisingly, we observed in
the NCCO, on the one hand, the Josephson current (with Nb tip) which indicates
the presence of s-wave order parameter, on the other hand, a zero-bias
conductance peak (with Ag tip) which is a manifestation of d-wave order
parameter. In addition, we find the presence of two distinct energy scales in
the underdoped NCCO: the smallest energy scale is associated with the Andreev
gap and c-axis tunneling gap, and the second scale corresponds to the maximum
in-plane tunneling gap. It seems that the phenomenon of superconductivity in
electron- and hole-doped cuprates can be understood within a common scheme.

</DOC>
<DOC>
<DOCNO> 170011 </DOCNO>
Variational Approach to Hydrogen Atom in Uniform Magnetic Field of


  Extending the Feynman-Kleinert variational approach, we calculate the
temperature-dependent effective classical potential governing the quantum
statistics of a hydrogen atom in a uniform magnetic at all temperatures. The
zero-temperature limit yields the binding energy of the electron which is quite
accurate for all magnetic field strengths and exhibits, in particular, the
correct logarithmic growth at large fields.

</DOC>
<DOC>
<DOCNO> 84557 </DOCNO>
Variational dynamics in open spacetimes


  We study the effect of non-vanishing surface terms at spatial infinity on the
dynamics of a scalar field in an open FLRW spacetime. Starting from the
path-integral formulation of quantum field theory we argue that classical
physics is described by field configurations which extremize the action
functional in the space of field configurations for which the variation of the
action is well defined. Since these field configurations are not required to
vanish outside a bounded domain, there is generally a non-vanishing
contribution of a surface term to the variation of the action. We then
investigate whether this surface term has an effect on the dynamics of the
action-extremizing field configurations. This question appears to be
surprisingly nontrivial in the case of the open FLRW geometry, since surface
terms tend to grow as fast as volume terms in the infinite volume limit. We
find that surface terms can be important for the dynamics of the field at a
classical and at a quantum level, when there are supercurvature perturbations.

</DOC>
<DOC>
<DOCNO> 39729 </DOCNO>
Rare Kaon Decays


  The current status of rare kaon decay experiments is reviewed. New limits in
the search for Lepton Flavor Violation are discussed, as are new measurements
of the CKM matrix.

</DOC>
<DOC>
<DOCNO> 9028 </DOCNO>
Charge on the quantum dot in the presence of tunneling current


  The calculation of the charge present in central region of the double barrier
structure at non-equilibrium conditions is discussed. We propose here a simple
method to calculate non equilibrium Green's functions which allows consistent
calculations of retarded and distribution functions. To illustrate the approach
we calculate the charge on the quantum dot coupled {\it via} tunnel barriers to
two external leads having different chemical potentials $\mu_L$ and $\mu_R$.
The obtained results have been compared with other approaches existing in the
literature. They all agree in the equilibrium situation and the departures grow
with increasing the difference $\mu_L-\mu_R$.

</DOC>
<DOC>
<DOCNO> 100279 </DOCNO>
Invariant subspaces of Voiculescu's circular operator


  We show that Voiculescu's circular operator and, more generally, each
circular free Poisson operator has a continuous family of invariant subspaces
relative to the von Neumann algebra it generates. The proof relies on upper
triangular random matrix models and consequent realizations of these operators
as upper triangular matrices of free random variables.

</DOC>
<DOC>
<DOCNO> 9087 </DOCNO>
Vortex configurations, matching, and domain structure in large arrays of


  High-resolution scanning Hall probe microscopy has been used to image vortex
configurations in very large periodic arrays of artificial pinning sites.
Strong matching effects are seen at fields where either one or two vortices can
sit at a site; with three vortices per site, however, no clear matching is
observed. Matching effects have been also been observed at several fractional
multiples of the matching field, including 1/5, 1/4, 1/3, 1/2, and 3/4. These
fractional values are characterized by striking domain structure and grain
boundaries.

</DOC>
<DOC>
<DOCNO> 151885 </DOCNO>
Topological Charges of Noncommutative Soliton


  The noncommutative soliton is characterized by the use of the projection
operators in non-commutative space. By using the close relation with the
K-theory of $C^*$-algebra, we consider the variations of projection operators
along the commutative directions and identify their topological charges. When
applied to the string theory, it gives the modification of the brane charges
due to tachyon background.

</DOC>
<DOC>
<DOCNO> 69183 </DOCNO>
Gluon Radiation off Hard Quarks in a Nuclear Environment: Opacity


  We study the relation between the Baier-Dokshitzer-Mueller-Peigne-Schiff
(BDMPS) and Zakharov formalisms for medium-induced gluon radiation off hard
quarks, and the radiation off very few scattering centers. Based on the
non-abelian Furry approximation for the motion of hard partons in a spatially
extended colour field, we derive a compact diagrammatic and explicitly colour
trivial expression for the N-th order term of the kt-differential gluon
radiation cross section in an expansion in the opacity of the medium. Resumming
this quantity to all orders in opacity, we obtain Zakharov's path-integral
expression (supplemented with a regularization prescription). This provides a
new proof of the equivalence of the BDMPS and Zakharov formalisms which extends
previous arguments to the kt-differential cross section. We give explicit
analytical results up to third order in opacity for both the gluon radiation
cross section of free incoming and of in-medium produced quarks. The N-th order
term in the opacity expansion of the radiation cross section is found to be a
convolution of the radiation associated to N-fold rescattering and a
readjustment of the probabilities that rescattering occurs with less than N
scattering centers. Both informations can be disentangled by factorizing out of
the radiation cross section a term which depends only on the mean free path of
the projectile. This allows to infer analytical expressions for the totally
coherent and totally incoherent limits of the radiation cross section to
arbitrary orders in opacity.

</DOC>
<DOC>
<DOCNO> 68547 </DOCNO>
Baryogenesis from `electrogenesis' in a scalar field dominated epoch


  Scalar fields can play a dominant role in the dynamics of the Universe until
shortly before nucleosynthesis. Examples are provided by domination by a
kinetic mode of a scalar field, which may be both the inflaton and the late
time `quintessence', and also by more conventional models of reheating. The
resultant modification to the pre-nucleosynthesis expansion rate can allow
solely an asymmetry in right handed electrons to produce a net baryon asymmetry
when reprocessed by the anomalous B+L violating processes of the standard
model. The production of such a source asymmetry - what we term
`electrogenesis' - requires no additional B or L violation beyond that in the
standard model. We consider a specific model for its generation, by a simple
perturbative out of equilibrium decay of Higgs like scalar fields with
CP-violating Yukawa couplings to the standard model leptons. We show that,
because of the much enhanced expansion rate, such a mechanism can easily
produce an adequate asymmetry from scalars with masses as low as 1 TeV. Kinetic
mode domination is strongly favoured because it evades large entropy release
which dilutes the asymmetry. We also discuss briefly the effect of the abelian
hypercharge anomaly.

</DOC>
<DOC>
<DOCNO> 11538 </DOCNO>
Fractionalization, topological order, and cuprate superconductivity


  This paper is concerned with the idea that the electron is fractionalized in
the cuprate high-$T_c$ materials. We show how the notion of topological order
may be used to develop a precise theoretical characterization of a
fractionalized phase in spatial dimension higher than one. Apart from the
fractional particles into which the electron breaks apart, there are
non-trivial gapped topological excitations - dubbed "visons". A cylindrical
sample that is fractionalized exhibits two disconnected topological sectors
depending on whether a vison is trapped in the "hole" or not. Indeed, "vison
expulsion" is to fractionalization what the Meissner effect ("flux expulsion")
is to superconductivity. This understanding enables us to address a number of
conceptual issues that need to be confronted by any theory of the cuprates
based on fractionalization ideas. We argue that whether or not the electron
fractionalizes in the cuprates is a sharp and well-posed question with a
definite answer. We elaborate on our recent proposal for an experiment to
unambiguously settle this issue.

</DOC>
<DOC>
<DOCNO> 123151 </DOCNO>
Mixing, Enhanced Helium and Blue Tails in Globular Clusters


  We investigate the consequences of an increase in the envelope helium
abundance of pre-helium flash red giants in globular clusters. Comparing
predictions with the CM diagrams of a few crucial GC, one finds no evidence for
a substantial increase in the surface helium content of HB members of these
clusters, at least for objects in the RR Lyrae region or close to it. The
possibility that the most peculiar giants belong to the asymptotic giant branch
is discussed. The consequences of a delay in the helium flash are briefly
examined.

</DOC>
<DOC>
<DOCNO> 11652 </DOCNO>
Many-Body Theory of Dilute Bose-Einstein Condensates with Internal


  The Bogoliubov theory of weakly interacting bosons is generalized to
Bose-Einstein condensates with internal degrees of freedom so that a single
effective Hamiltonian produces various many-body ground states or metastable
spin domains and the corresponding collective modes on an equal footing.

</DOC>
<DOC>
<DOCNO> 102436 </DOCNO>
A simple proof of the Fredholm alternative and a characterization of the


  Let $A$ be a linear bounded operator in a Hilbert space $H$, $N(A)$ and
$R(A)$ its null-space and range, and $A^*$ its adjoint. The operator $A$ is
called Fredholm iff $dim N(A)= dim N(A^*):=n<\infty$ and $R(A)$ and $R(A^*)$
are closed subspaces of $H$.
  A simple and short proof is given of the following known result: $A$ is
Fredholm iff $A=B+F$, where $B$ is an isomorphism and $F$ is a finite-rank
operator. The proof consists in reduction to a finite-dimensional linear
algebraic system which is equivalent to the equation $Au=f$ in the case of
Fredholm operators.

</DOC>
<DOC>
<DOCNO> 99458 </DOCNO>
On the Schlafli differential formula


  he celebrated formula of Schlafli relates the variation of the dihedral
angles of a smooth family of polyhedra in a space form and the variation of
volume. We give a smooth analogue of this classical formula -- our result
relates the variation of the volume bounded by a hypersurface moving in a
general Einstein manifold and the integral of the variation of the mean
curvature. The argument is direct, and the classical polyhedral result (as well
as results for Lorenzian space forms) is an easy corollary. We extend it to
variations of the metric in a Riemannian Einstein manifold with boundary. We
apply our results to extend the classical Euclidean inequalities of Aleksandrov
to other 3-dimensional constant curvature spaces. We also obtain rigidity
results for Ricci-flat manifolds with umbilic boundaries and existence results
for foliations of Einstein manifolds by hypersurfaces.

</DOC>
<DOC>
<DOCNO> 84372 </DOCNO>
Can a Kasner Universe with a Viscous Cosmological Fluid be Anisotropic?


  A Bianchi type -I metric of Kasner form is considered, when the space is
filled with a viscous fluid. Whereas an ideal (nonviscous) fluid permits the
Kasner metric to be anisotropic provided that the fluid satisfies the
Zel'dovich equation of state, the viscous fluid does not permit the Kasner
metric to be anisotropic at all. In the latter case, we calculate the Kasner
(isotropic) metric expressed by the fluid's density, pressure, and bulk
viscosity, at some chosen instant $t=t_0$. The equation of state is also
calculated. The present paper is related to a recent Comment of Cataldo and del
Campo [Phys. Rev. D, scheduled to April 15, 2000], on a previous work of the
present authors [Phys. Rev. D {\bf 56}, 3322 (1997)].

</DOC>
<DOC>
<DOCNO> 122952 </DOCNO>
Dynamical variations of the differential rotation in the solar


  Recent analyses of helioseismological observations seem to suggest the
presence of two new phenomena connected with the dynamics of the solar
convective zone. Firstly, there are present torsional oscillations with periods
of about 11 years, which penetrate significantly into the solar convection zone
and secondly, oscillatory regimes exist near the base of the convection which
are markedly different from those observed near the top, having either
significantly reduced periods or being non-periodic.
  Recently spatiotemporal fragmentation/bifurcation has been proposed as a
possible dynamical mechanism to account for such observed multi-mode behaviours
in different parts of the solar convection zone. Evidence for this scenario was
produced in the context of an axisymmetric mean field dynamo model operating in
a spherical shell, with a semi-open outer boundary condition and a zero order
angular velocity obtained by the inversion of the MDI data, in which the only
nonlinearity was the action of the Lorentz force of the dynamo generated
magnetic field on the solar angular velocity.
  Here we make a detailed study of the robustness of this model with respect to
plausible changes to its main ingredients, including changes to the alpha and
eta profiles as well as the inclusion of a nonlinear alpha quenching. We find
that spatiotemporal fragmentation is present in this model for different
choices of the rotation data and as the details of the model are varied. Taken
together, these results give strong support to the idea that spatiotemporal
fragmentation is likely to occur in general dynamo settings.

</DOC>
<DOC>
<DOCNO> 85010 </DOCNO>
On the potentials yielding cosmological scaling solutions


  In the present work we perform a phase-plane analysis of the complete
dynamical system corresponding to a flat FRW cosmological models with a perfect
fluid and a self-interacting scalar field and show that every positive and
monotonous potential which is asymptotically exponential yields a scaling
solution as a global attractor.

</DOC>
<DOC>
<DOCNO> 84081 </DOCNO>
Atom made from charged elementary black hole


  It is believed that there may have been a large number of black holes formed
in the very early universe. These would have quantised masses. A charged
``elementary black hole'' (with the minimum possible mass) can capture
electrons, protons and other charged particles to form a ``black hole atom''.
We find the spectrum of such an object with a view to laboratory and
astronomical observation of them, and estimate the lifetime of the bound
states. There is no limit to the charge of the black hole, which gives us the
possibility of observing Z>137 bound states and transitions at the lower
continuum. Negatively charged black holes can capture protons. For Z>1, the
orbiting protons will coalesce to form a nucleus (after beta-decay of some
protons to neutrons), with a stability curve different to that of free nuclei.
In this system there is also the distinct possibility of single quark capture.
This leads to the formation of a coloured black hole that plays the role of an
extremely heavy quark interacting strongly with the other two quarks. Finally
we consider atoms formed with much larger black holes.

</DOC>
<DOC>
<DOCNO> 122135 </DOCNO>
A jet model for the broadband spectrum of XTE J1118+480: Synchrotron


  Observations have revealed strong evidence for powerful jets in the Low/Hard
states of black hole candidate X-ray binaries. Correlations, both temporal and
spectral, between the radio -- infrared and X-ray bands suggest that jet
synchrotron as well as inverse Compton emission could also be significantly
contributing at higher frequencies. We show here that, for reasonable
assumptions about the jet physical parameters, the broadband spectrum from
radio through X-rays can be almost entirely fit by synchrotron emission. We
explore a relatively simple model for a relativistic, adiabatically expanding
jet combined with a truncated thermal disk conjoined by an ADAF, in the context
of the recently discovered black hole binary XTE J1118+480. In particular, the
X-ray power-law emission can be explained as optically thin synchrotron
emission from a shock acceleration region in the innermost part of the jet,
with a cutoff determined by cooling losses. For synchrotron cooling-limited
particle acceleration, the spectral cutoff is a function only of dimensionless
plasma parameters and thus should be around a ``canonical'' value for sources
with similar plasma properties. It is therefore possible that non-thermal jet
emission is important for XTE J1118+480 and possibly other X-ray binaries in
the Low/Hard state.

</DOC>
<DOC>
<DOCNO> 100003 </DOCNO>
Characteristic Classes for GO(2n,C)


  The complex Lie group GO(2n,C) by definition consists of all complex matrices
A of size 2n, such that A times transpose(A) is a non-zero scalar. In this
paper we determine explicitly the singular cohomology ring of the classifying
space BGO(2n,C) with mod 2 coefficients, in terms of generators and relations.
The method consists of analysing a certain derivation on the cohomology ring of
BO(2n) (which is a polynomial ring in the Stiefel-Whitney classes) via a Koszul
complex, and using this to `solve' the Gysin sequence for the bundle BO(2n)
over BGO(2n,C).

</DOC>
<DOC>
<DOCNO> 116687 </DOCNO>
Electron-hole pairs multiquantum generation mechanizm in the process of


  The luminecsence of ZnSCdS-Cu phosphors of various CdS consentration (0-40%)
is under investigation. The luminescence was exited by hydrogen atoms during
adsorbtion of thermal energy during adsorbtion and impact
recombination-heterogeneous chemiluminenscence(HCL) are discussed. The monotone
lowering of the conductivity zone bottom level with respect to the valence zone
ceiling (from 3,7 eV to 3,2 eV) with increasing CdS concentration (from 0 -
40%). HCL intensity with respect to CdS (from 3,7 eV to 3,2 eV)- concentration
($E_g$)grows rapidly. The dependence of HCL intensity on the forbidden zone
width can be explained by the action of electron - hole pairs multiquontum
generation mechanism.

</DOC>
<DOC>
<DOCNO> 14114 </DOCNO>
Spin Excitations in the Two-leg Ladder Antiferromagnet CaV$_2$O$_5$


  The nuclear spin-lattice relaxation rate (1/T1) at the V sites in CaV2O5 was
measured. The result was compared with the calculation for the two-leg ladder
with the strong-coupling expansion. We found a good agreement on the
temperature and magnetic field dependence but a discrepancy between the
exchange parameters deduced from 1/T1 and the magnetic susceptibility.

</DOC>
<DOC>
<DOCNO> 71552 </DOCNO>
Stationary dark energy: the present universe as a global attractor


  We propose a cosmological model that makes a significant step toward solving
the coincidence problem of the near similarity at the present of the dark
energy and dark matter components. Our cosmology has the following properties:
a) among flat and homogeneous spaces, the present universe is a global
attractor: all the possible initial conditions lead to the observed proportion
of dark energy and dark matter; once reached, it remains fixed forever; b) the
expansion is accelerated at the present, as requested by the supernovae
observations; c) the model is consistent with the large-scale structure and
microwave background data; d) the dark energy and the dark matter densities
always scale similarly after equivalence and are close to within two orders of
magnitude. The model makes use of a non-linear coupling of the dark energy to
the dark matter that switches on after structure formation.

</DOC>
<DOC>
<DOCNO> 83081 </DOCNO>
Multiplicative Nonholonomic/Newton -like Algorithm


  We construct new algorithms from scratch, which use the fourth order cumulant
of stochastic variables for the cost function. The multiplicative updating rule
here constructed is natural from the homogeneous nature of the Lie group and
has numerous merits for the rigorous treatment of the dynamics. As one
consequence, the second order convergence is shown. For the cost function,
functions invariant under the componentwise scaling are choosen. By identifying
points which can be transformed to each other by the scaling, we assume that
the dynamics is in a coset space. In our method, a point can move toward any
direction in this coset. Thus, no prewhitening is required.

</DOC>
<DOC>
<DOCNO> 122761 </DOCNO>
The ATCA/VLA OH 1612 MHz survey. III. Northern Galactic Plane


  We present observations of the region between 5deg < l < 45deg and |b| <
3deg, in the OH 1612 MHz line, taken from 1993 to 1995 with the VLA. These
observations are the last part of a larger survey, covering |l| < 45deg and |b|
< 3deg, with the ATCA and the VLA. The region was systematically observed on a
30'x30' grid in (l,b) and the resulting coverage was 92%, with 965 pointings.
We found 286 OH--masing objects, 161 of which are new detections and 207 have
reliable IRAS point-source identifications. The outflow velocity was determined
for 276 sources. A total of 766 sources were detected in the combined ATCA/VLA
survey, of which 29 were detected in two regions of the survey. The source
tables and spectra may be downloaded from
http://msowww.anu.edu.au/~msevenst/pubs.html In this article we analyse the
data statistically and give identifications with known sources where possible.
The efficiency of this VLA survey is 75% of that of the ATCA Bulge survey. This
efficiency was determined by comparing the detections in the region where the
two surveys overlap. The completeness- and error characteristics are similar,
though less homogeneous, except for the much larger errors in the flux
densities. The relatively large surface number density found in the northern
disk, suggests that we can see the Bar extending to higher longitudes on this
side of the galactic Centre.

</DOC>
<DOC>
<DOCNO> 120512 </DOCNO>
MACHOs and the clouds of uncertainty


  I review proposals for explaining the current gravitational microlensing
results from the EROS and MACHO surveys towards the Magellanic Clouds.
Solutions involving massive compact halo objects (MACHOs), both baryonic and
non-baryonic, as well as solutions that do not require MACHOs, are discussed.
Whilst the existence and nature of MACHOs remains to be established, the
prospects for achieving this over the next few years are good.

</DOC>
<DOC>
<DOCNO> 8841 </DOCNO>
Macroscopic material properties from quasi-static, microscopic


  One of the essential questions in the area of granular matter is, how to
obtain macroscopic tensorial quantities like stress and strain from
``microscopic'' quantities like the contact forces in a granular assembly.
Different averaging strategies are introduced, tested, and used to obtain
volume fractions, coordination numbers, and fabric properties. We derive anew
the non-trivial relation for the stress tensor that allows a straightforward
calculation of the mean stress from discrete element simulations and comment on
the applicability. Furthermore, we derive the ``elastic'' (reversible) mean
displacement gradient, based on a best-fit hypothesis. Finally, different
combinations of the tensorial quantities are used to compute some material
properties.
  The bulk modulus, i.e. the stiffness of the granulate, is a linear function
of the trace of the fabric tensor which itself is proportional to the density
and the coordination number. The fabric, the stress and the strain tensors are
{\em not} co-linear so that a more refined analysis than a classical elasticity
theory is required.

</DOC>
<DOC>
<DOCNO> 70114 </DOCNO>
Further studies on relic neutrino asymmetry generation I: the adiabatic


  We demonstrate that the relic neutrino asymmetry evolution equation derived
from the quantum kinetic equations (QKEs) reduces to the Boltzmann limit that
is dependent only on the instantaneous neutrino number densities, in the
adiabatic limit in conjunction with sufficient damping. An original physical
and/or geometrical interpretation of the adiabatic approximation is given,
which serves as a convenient visual aid to understanding the sharply
contrasting resonance behaviours exhibited by the neutrino ensemble in opposing
collision regimes. We also present a classical analogue for the evolution of
the difference in $\nu_{\alpha}$ and $\nu_s$ number densities which, in the
Boltzmann limit, is akin to the behaviour of the generic reaction $A
\rightleftharpoons B$ with equal forward and reverse reaction rate constants. A
new characteristic quantity, the matter and collision-affected mixing angle of
the neutrino ensemble, is identified here for the first time. The role of
collisions is revealed to be twofold: (i) to wipe out the inherent
oscillations, and (ii) to equilibrate the $\nu_{\alpha}$ and $\nu_s$ number
densities in the long run. Studies on non-adiabatic evolution and its possible
relation to rapid oscillations in lepton number generation also feature, with
the introduction of an adiabaticity parameter for collision-affected
oscillations.

</DOC>
<DOC>
<DOCNO> 150795 </DOCNO>
Two-loop Feynman Diagrams in Yang-Mills Theory from Bosonic String


  We present intermediate results of an ongoing investigation which attempts a
generalization of the well known one-loop Bern Kosower rules of Yang-Mills
theory to higher loop orders. We set up a general procedure to extract the
field theoretical limit of bosonic open string diagrams, based on the sewing
construction of higher loop world sheets. It is tested with one- and two-loop
scalar field theory, as well as one-loop and two-loop vacuum Yang-Mills
diagrams, reproducing earlier results. It is then applied to two-loop two-point
Yang-Mills diagrams in order to extract universal renormalization coefficients
that can be compared to field theory. While developing numerous technical tools
to compute the relevant contributions, we hit upon important conceptual
questions: Do string diagrams reproduce Yang-Mills Feynman diagrams in a
certain preferred gauge? Do they employ a certain preferred renormalization
scheme? Are four gluon vertices related to three gluon vertices? Unfortunately,
our investigations remained inconclusive up to now.

</DOC>
<DOC>
<DOCNO> 101149 </DOCNO>
Approximation of *weak-to-norm continuous mappings


  The purpose of this paper is to study the approximation of vector valued
mappings defined on a subset of a normed space. We investigate Korovkin-type
conditions under which a given sequence of linear operators becomes a so-called
approximation process. First, we give a sufficient condition for this sequence
to approximate the class of bounded, uniformly continuous functions. Then we
present some sufficient and necessary conditions guaranteeing the approximation
within the class of unbounded, *weak-to-norm continuous mappings. We also
derive some estimates of the rate of convergence.

</DOC>
<DOC>
<DOCNO> 9936 </DOCNO>
Spin Properties of Low Density One-Dimensional Wires


  We report conductance measurements of a ballistic one-dimensional (1D) wire
defined in the lower two-dimensional electron gas of a GaAs/AlGaAs double
quantum well. At low temperatures there is an additional structure at
$0.7(2e^2/h)$ in the conductance, which tends to $e^2/h$ as the electron
density is decreased. We find evidence for complete spin polarization in a
weakly disorderd 1D wire at zero magnetic field through the observation of a
conductance plateau at $e^2/h$, which strengthens in an in-plane magnetic field
and disappears with increasing electron density. In all cases studied, with
increasing temperature structure occurs at $0.6(2e^2/h)$. We suggest that the
0.7 structure is a many-body spin state excited out of, either the
spin-polarized electron gas at low densities, or the spin-degenerate electron
gas at high densities.

</DOC>
<DOC>
<DOCNO> 13890 </DOCNO>
Abrupt Transition between Thermally-Activated Relaxation and Quantum


  We report Hall sensor measurements of the magnetic relaxation of Mn$_{12}$
acetate as a function of magnetic field applied along the easy axis of
magnetization. Data taken at a series of closely-spaced temperatures between
0.24 K and 1.4 K provide strong new evidence for an abrupt ``first-order''
transition between thermally-assisted relaxation and magnetic decay via quantum
tunneling.

</DOC>
<DOC>
<DOCNO> 84672 </DOCNO>
Feynman Clocks, Causal Networks, and The Origin of Hierarchical 'Arrows


  A theory of time as 'information' is outlined using new tools such as Feynman
Clocks (FCs), Collective Excitation Networks (CENs), Sequential Excitation
Networks (SENs), and Plateaus of Complexity (POCs). Applications of this
approach range from the Big Bang to the emergence of 'consciousness'.

</DOC>
<DOC>
<DOCNO> 151533 </DOCNO>
Recent Progress in Superstring Theory


  Superstring theory has continued to develop at a rapid clip in the past few
years. Following a quick review of some of the major discoveries prior to 1998,
this talk focuses on a few of the more recent developments. The topics I have
chosen to present are 1) the use of K-theory to classify conserved charges
carried by D-branes; 2) tachyon condensation on unstable D-brane systems; and
3) an introduction to noncommutative field theories and their solitons.

</DOC>
<DOC>
<DOCNO> 100482 </DOCNO>
Grothendieck groups and tilting objects


  Let C be a connected noetherian hereditary abelian Ext-finite category with
Serre functor over an algebraically closed field k, with finite dimensional
homomorphism and extension spaces. Using the classification of such categories
from math.RT/9911242, we prove that if C has some object of infinite length,
then the Grothendieck group of C is finitely generated if and only if C has a
tilting object.

</DOC>
<DOC>
<DOCNO> 99827 </DOCNO>
When is the Fourier transform of an elementary function elementary?


  Let V be a finite dimensional vector space over a local field. Let us say
that a complex function on V is elementary if it is a product of the additive
character of a rational function Q on V and multiplicative characters of
polynomials on V.
  In this paper we study when the Fourier transform of an elementary function
is elementary. If Q has a nonzero Hessian, a necessary condition for this is
that the Legendre transform Q_* of Q is rational. The basic example is a
nondegenerate quadratic form. We study such functions Q, give examples, and
find all of them such that both Q and Q_* are of the form f(x)/t, where f is a
cubic form in many variables (the simplest case after quadratic forms). It
turns out that this classification is closely related to Zak's classification
of Severi varieties.
  The second half of the paper is devoted to finding and classifying elementary
functions with elementary Fourier transforms when Q is a fixed function with
rational Q_*. We consider the simplest case when Q is a monomial, and classify
combinations of multiplicative characters that can arise. The answer (for real
and complex fields) is given in terms of exact covering systems. We also
describe examples related to prehomogeneous vector spaces. Finally, we consider
examples over p-adic fields, and in particular give a local proof of an
integral formula of D.K. that could previously be proved only by a global
method.

</DOC>
<DOC>
<DOCNO> 151764 </DOCNO>
Analogues of Discrete Torsion for the M-Theory Three-Form


  In this article we shall outline a derivation of the analogue of discrete
torsion for the M-theory three-form potential. We find that some of the
differences between orbifold group actions on the C field are classified by
H^3(G, U(1)). We also compute the phases that the low-energy effective action
of a membrane on T^3 would see in the analogue of a twisted sector, and note
that they are invariant under the obvious SL(3,Z) action.

</DOC>
<DOC>
<DOCNO> 68077 </DOCNO>
Primordial Adiabatic Fluctuations from Cosmic Defects


  We point out that in the context of ``two-metric'' theories of gravity there
is the possibility that cosmic defects will produce a spectrum of primordial
adiabatic density perturbations. This will happen when the speed characterising
the defect-producing scalar field is much larger than the speed characterising
gravity and all standard model particles. This model will exactly mimic the
standard predictions of inflationary models, with the exception of a small
non-Gaussian signal which could be detected by future experiments. We briefly
discuss defect evolution in these scenarios and analyze their cosmological
consequences.

</DOC>
<DOC>
<DOCNO> 8320 </DOCNO>
Quantum entanglement using trapped atomic spins


  We propose an implementation for quantum logic and computing using trapped
atomic spins of two different species, interacting via direct magnetic
spin-spin interaction. In this scheme, the spins (electronic or nuclear) of
distantly spaced trapped neutral atoms serve as the qubit arrays for quantum
information processing and storage, and the controlled interaction between two
spins, as required for universal quantum computing, is implemented in a three
step process that involves state swapping with a movable auxiliary spin.

</DOC>
<DOC>
<DOCNO> 70704 </DOCNO>
Next-to-leading Order SUSY-QCD Calculation of Associated Production of


  Results are presented of a next-to-leading order calculation in perturbative
QCD of the production of charginos and neutralinos in association with gluinos
at hadron colliders. Predictions for cross sections are shown at the energies
of the Fermilab Tevatron and CERN Large Hadron Collider for a typical
supergravity (SUGRA) model of the sparticle mass spectrum and for a light
gluino model.

</DOC>
<DOC>
<DOCNO> 71323 </DOCNO>
The Free Energy Of Hot Gauge Theories


  The total perturbative contribution to the free-energy of hot SU(3) gauge
theory is argued to lie significantly higher than the full result obtained by
lattice simulations. This then suggests the existence of large non-perturbative
corrections even at temperatures a few times above the critical temperature.
Some speculations are then made on the nature and origin of the
non-perturbative corrections. The analysis is then carried out for quantum
chromodynamics, $SU(N_c)$ gauge theories, and quantum electrodynamics, leading
to a conjecture and one more speculation.

</DOC>
<DOC>
<DOCNO> 117274 </DOCNO>
Fast and stable method for simulating quantum electron dynamics


  A fast and stable method is formulated to compute the time evolution of a
wavefunction by numerically solving the time-dependent Schr{\"o}dinger
equation. This method is a real space/real time evolution method implemented by
several computational techniques such as Suzuki's exponential product, Cayley's
form, the finite differential method and an operator named adhesive operator.
This method conserves the norm of the wavefunction, manages periodic conditions
and adaptive mesh refinement technique, and is suitable for vector- and
parallel-type supercomputers. Applying this method to some simple electron
dynamics, we confirmed the efficiency and accuracy of the method for simulating
fast time-dependent quantum phenomena.

</DOC>
<DOC>
<DOCNO> 68794 </DOCNO>
Space-time Autocorrelations and Hubble Flow: Probing Small Length Scales


  We extend the usual treatment of two-particle momentum correlations to
include the possibility of non-chaotic or correlated particle emission from the
hadronic freeze-out surface in heavy-ion collisions. We adopt a modified
two-particle emission density which permits the description of nontrivial
differences between pair autocorrelations for different pair types. If
different pair types sample nuclear radial or Hubble flow in different ways we
predict a unique signature in two-particle momentum distributions. Analysis of
such effects may provide detailed information on the small-scale structure of
the freeze-out surface.

</DOC>
<DOC>
<DOCNO> 101904 </DOCNO>
Existence and uniqueness of the integrated density of states for


  The object of the present study is the integrated density of states of a
quantum particle in multi-dimensional Euclidean space which is characterized by
a Schr\"odinger operator with a constant magnetic field and a random potential
which may be unbounded from above and from below. For an ergodic random
potential satisfying a simple moment condition, we give a detailed proof that
the infinite-volume limits of spatial eigenvalue concentrations of
finite-volume operators with different boundary conditions exist almost surely.
Since all these limits are shown to coincide with the expectation of the trace
of the spatially localized spectral family of the infinite-volume operator, the
integrated density of states is almost surely non-random and independent of the
chosen boundary condition. Our proof of the independence of the boundary
condition builds on and generalizes certain results by S. Doi, A. Iwatsuka and
T. Mine [Math. Z. {\bf 237} (2001) 335-371] and S. Nakamura [J. Funct. Anal.
{\bf 173} (2001) 136-152].

</DOC>
<DOC>
<DOCNO> 69358 </DOCNO>
High-dimensional sources for the four-dimensional gravity


  We argue that a certain distribution of matter in higher dimensions can
provide the correct behaviour of gravity in four dimensions. Some explicit
examples illustrating the idea are considered.

</DOC>
<DOC>
<DOCNO> 120462 </DOCNO>
The transition to nonlinearity and new constraints on biasing


  We present two new dynamical tests of the biasing hypothesis. The first is
based on the amplitude and the shape of the galaxy-galaxy correlation function,
$\xi_g(r)$, where $r$ is the separation of the galaxy pair. The second test
uses the mean relative peculiar velocity for galaxy pairs, $\vs(r)$. This
quantity is a measure of the rate of growth of clustering and it is related to
the two-point correlation function for the matter density fluctuations,
$\xi(r)$. Under the assumption that galaxies trace the mass ($\xi_g = \xi$),
the expected relative velocity can be calculated directly from the observed
galaxy clustering. The above assumption can be tested by confronting the
expected $\vs$ with direct measurements from velocity-distance surveys. Both
our methods are checked against N-body experiments and then compared with the
$\xi_g(r)$ and $\vs$ estimated from the {\sc APM} galaxy survey and the Mark
III catalogue, respectively. Our results suggest that cosmological density
parameter is low, $\Omega_m \approx 0.3$, and that the {\sc APM} galaxies trace
the mass at separations $r \ga 5 \Mlu$, where $h$ is the Hubble constant in
units of 100 km s$^{-1}$Mpc. The present results agree with earlier studies,
based on comparing higher order correlations in the {\sc APM} with weakly
non-linear perturbation theory. Both approaches constrain the linear bias
factor to be within 20% of unity. If the existence of the feature we identified
in the {\sc APM} $\xi_g(r)$ -- the inflection point near $\xi_g = 1$ -- is
confirmed by more accurate surveys, we may have discovered gravity's smoking
gun: the long awaited ``shoulder'' in $\xi$, generated by gravitational
dynamics and predicted by Gott and Rees 25 years ago.

</DOC>
<DOC>
<DOCNO> 100125 </DOCNO>
Identically Distributed Pairs of Partition Statistics


  We show that many theorems which assert that two kinds of partitions of the
same integer $n$ are equinumerous are actually special cases of a much stronger
form of equality. We show that in fact there correspond partition statistics
$X$ and $Y$ that have identical distribution functions. The method is an
extension of the principle of sieve-equivalence, and it yields simple criteria
under which we can infer this identity of distribution functions.

</DOC>
<DOC>
<DOCNO> 13770 </DOCNO>
Iterative Perturbation Theory for Strongly Correlated Electron Systems


  A new scheme of the iterative perturbation theory is proposed for the
strongly correlated electron systems with orbital degeneracy. The method is
based on the modified self-energy of Yeyati, et al. which interpolates between
the weak and the strong correlation limits, but a much simpler scheme is
proposed which is useful in the case of the strong correlation with orbital
degeneracy. It will be also useful in the study of the electronic structures
combined with the band calculations.

</DOC>
<DOC>
<DOCNO> 151674 </DOCNO>
Gravity on a Brane in Infinite-Volume Extra Space


  We generalize the mechanism proposed in [hep-th/0005016] and show that a
four-dimensional relativistic tensor theory of gravitation can be obtained on a
delta-function brane in flat infinite-volume extra space. In particular, we
demonstrate that the induced Ricci scalar gives rise to Einstein's gravity on a
delta-function type brane if the number of space-time dimensions is bigger than
five. The bulk space exhibits the phenomenon of infrared transparency. That is
to say, the bulk can be probed by gravitons with vanishing four-dimensional
momentum square, while it is unaccessible to higher modes. This provides an
attractive framework for solving the cosmological constant problem.

</DOC>
<DOC>
<DOCNO> 69355 </DOCNO>
Roy equation analysis of pi pi scattering


  We analyze the Roy equations for the lowest partial waves of elastic pi pi
scattering and demonstrate that the two S-wave scattering lengths a_0^0 and
a_0^2 are the essential parameters in the low energy region: Once these are
known, the available experimental information determines the behaviour near
threshold to within remarkably small uncertainties. An explicit numerical
representation for the energy dependence of the S- and P-waves is given and it
is shown that the threshold parameters of the D- and F-waves are also fixed
very sharply in terms of a_0^0 and a^2_0. In agreement with earlier work, which
is reviewed in some detail, we find that the Roy equations admit physically
acceptable solutions only within a band of the (a_0^0,a_0^2) plane. We show
that the data on the reactions e+e- -> pi pi and tau -> pi pi nu reduce the
width of this band quite significantly. Furthermore, we discuss the relevance
of the decay K -> pi pi e nu in restricting the allowed range of a_0^0,
preparing the grounds for an analysis of the forthcoming precision data on this
decay and on pionic atoms. We expect these to reduce the uncertainties in the
two basic low energy parameters very substantially, so that a meaningful test
of the chiral perturbation theory predictions will become possible.

</DOC>
<DOC>
<DOCNO> 69844 </DOCNO>
The Pomeron intercept in $\lambda\phi^3$ theory in 4 Minkowski + 1


  We calculate the total cross section for two scalar particles scattering at
high energies in $\lambda\phi^3$ theory in five dimensions, four of which are
usual Minkowski ones and the fifth is compact. It is shown that the cross
section is dominated by exchange of Pomeron whose intercept is larger than in
usual four-dimensional case.

</DOC>
<DOC>
<DOCNO> 151956 </DOCNO>
The phase transition in the multiflavour Schwinger model


  A summary is given of a quantization of the multiflavour Schwinger model on a
finite-temperature cylinder with chirality-breaking boundary conditions at its
spatial ends, and it is shown that the analytic expression for the chiral
condensate implies that the theory exhibits a second order phase transition
with $T_c = 0$.

</DOC>
<DOC>
<DOCNO> 170537 </DOCNO>
Entangling ions in arrays of microscopic traps


  We consider a system of particles in an array of microscopic traps, coupled
to each other via electrostatic interaction, and pushed by an external
state-dependent force. We show how to implement a two-qubit quantum gate
between two such particles with a high fidelity.

</DOC>
<DOC>
<DOCNO> 100245 </DOCNO>
On the Dunford-Pettis Property of the Tensor product of C(K) spaces


  We characterize those compact Hausdorff spaces K such that the proyective
tensor product of C(K) by itself has the Dunford-Pettis Property, answering
thus in the negative a question posed by Castillo and Gonzalez.

</DOC>
<DOC>
<DOCNO> 150387 </DOCNO>
On the Equivalence between Noncommutative and Ordinary Gauge Theories


  Recently Seiberg and Witten have proposed that noncommutative gauge theories
realized as effective theories on D-brane are equivalent to some ordinary gauge
theories. This proposal has been proved, however, only for the
Dirac-Born-Infeld action in the approximation of neglecting all derivative
terms. In this paper we explicitly construct general forms of the 2n-derivative
terms which satisfy this equivalence under their assumption in the
approximation of neglecting (2 n+2)-derivative terms. We also prove that the
D-brane action computed in the superstring theory is consistent with the
equivalence neglecting the fourth and higher order derivative terms.

</DOC>
<DOC>
<DOCNO> 123227 </DOCNO>
Self-Similar Evolution of Wind-Blown Bubbles with Mass-loading by


  We present similarity solutions for mass-loaded adiabatic bubbles that are
blown by winds having time dependent mechanical luminosities. We consider
mass-loading through conductive evaporation of clumps. In the limit of little
mass loading a similarity solution found by Dyson (1973) for expansion into a
smooth ambient medium is recovered. We find that the Mach number in the shocked
mass-loaded wind shows a radial dependence that varies qualitatively from
solution to solution. In some cases it is everywhere less than unity in the
frame of the clumps being evaporated, while in others it is everywhere greater
than unity. In some solutions the mass-loaded shocked wind undergoes one or two
sonic transitions in the clump frame. Maximum possible values of the ratio of
evaporated mass to stellar wind mass are found as a consequence of the
evaporation rates dependence on temperature and the lowering of the temperature
by mass-loading. Mass-loading tends to reduce the emissivity in the interior of
the bubble relative to its limb, whilst simultaneously increasing the central
temperature relative to the limb temperature.

</DOC>
<DOC>
<DOCNO> 71956 </DOCNO>
Seesaw neutrino masses and mixing with extended democracy


  In the context of a minimal extension of the Standard Model with three extra
heavy right-handed neutrinos, we propose a model for neutrino masses and mixing
based on the hipothesis of a complete alignment of the lepton mass matrices in
flavour space. Considering a uniform quasi-democratic structure for these
matrices, we show that, in the presence of a highly hierarchical right-handed
neutrino mass spectrum, the effective neutrino mass matrix, obtained through
the seesaw mechanism, can reproduce all the solutions of the solar neutrino
problem.

</DOC>
<DOC>
<DOCNO> 121248 </DOCNO>
Precessing warped accretion discs in X-ray binaries


  We study the radiation-driven warping of accretion discs in the context of
X-ray binaries. The latest evolutionary equations are adopted, which extend the
classical alpha theory to time-dependent thin discs with non-linear warps. We
also develop accurate, analytical expressions for the tidal torque and the
radiation torque, including self-shadowing.
  We investigate the possible non-linear dynamics of the system within the
framework of bifurcation theory. First, we re-examine the stability of an
initially flat disc to the Pringle instability. Then we compute directly the
branches of non-linear solutions representing steadily precessing discs.
Finally, we determine the stability of the non-linear solutions. Each problem
involves only ordinary differential equations, allowing a rapid, accurate and
well resolved solution.
  We find that radiation-driven warping is probably not a common occurrence in
low-mass X-ray binaries. We also find that stable, steadily precessing discs
exist for a narrow range of parameters close to the stability limit. This could
explain why so few systems show clear, repeatable `super-orbital' variations.
The best examples of such systems, Her X-1, SS 433 and LMC X-4, all lie close
to the stability limit for a reasonable choice of parameters. Systems far from
the stability limit, including Cyg X-2, Cen X-3 and SMC X-1, probably
experience quasi-periodic or chaotic variability as first noticed by Wijers &
Pringle. We show that radiation-driven warping provides a coherent and
persuasive framework but that it does not provide a generic explanation for the
long-term variabilities in all X-ray binaries.

</DOC>
<DOC>
<DOCNO> 170157 </DOCNO>
Experimental implementation of a four-level N-type scheme for the


  A nondegenerate four-level N-type scheme was experimentally implemented to
observe electromagnetically induced transparency (EIT) at the $^{87}$Rb D$_{2}$
line. Radiations of two independent external-cavity semiconductor lasers were
used in the experiment, the current of one of them being modulated at a
frequency equal to the hyperfine-splitting frequency of the excited 5P$_{3/2}$
level. In this case, apart from the main EIT dip corresponding to the
two-photon Raman resonance in a three-level $\Lambda$-scheme, additional dips
detuned from the main dip by a frequency equal to the frequency of the HF
generator were observed in the absorption spectrum. These dips were due to an
increase in the medium transparency at frequencies corresponding to the
three-photon Raman resonances in four-level N-type schemes. The resonance
shapes are analyzed as functions of generator frequency and magnetic field.

</DOC>
<DOC>
<DOCNO> 116519 </DOCNO>
The Universe: Finite or Infinite ?


  The universe either originated from absolute nothing or it always existed.
Some form of the latter alternative is usually preferred. It is shown that the
former alternative is the actual case and that the universe is finite in extent
and duration, not infinite.

</DOC>
<DOC>
<DOCNO> 116556 </DOCNO>
M\'etodos Estoc\'asticos em Turbul\^encia Desenvolvida


  In this thesis, we use some methods of theory of stochastic process to
approach turbulence in fluid dynamics. We discuss the Kolmogorov model for
fully developed homogeneous turbulence, some recent analytical results to the
1-D Burgers' equation approach turbulence. Nesta disserta\c c\~ao, utilizamos
m\'etodos da teoria de processos estoc\'asticos para a compreens\~ao da
turbul\^encia em fluidos. Discutimos o modelo de Kolmogorov para turbul\^encia
homog\^enea desenvolvida, resultados anal\'\i ticos recentes para a equa\c
c\~ao de Burgers.

</DOC>
<DOC>
<DOCNO> 122015 </DOCNO>
UVES observations of QSO 0000-2620: Argon and Phosphorus abundances in


  The UV resonance transitions of neutral argon ArI 1066 A, and of singly
ionized phosphorus PII 963 A, originated in the damped Ly_alpha system (DLA) at
zabs = 3.3901 towards QSO 0000--2620 have been detected by means of the UVES
spectrograph at the 8.2m ESO KUEYEN telescope. So far, this is the first
measurement of ArI, and the second of PII, ever performed in damped galaxies
and in high redshift objects. This DLA is well known for having one of the
lowest metal abundances and dust content, and the lowest fractional abundance
of molecular hydrogen H_2. The measured Ar abundance is [Ar/H] = - 1.91 (+/-
0.09) which is equal to the abundances of the other alpha-chain elements (O, S
and Si). The similarity of the Ar abundance with the other alpha-chain elements
implies the absence of significant photoionization by either UV background or
stellar sources along the sightline throughout the damped Ly_alpha system. Both
log(Ar/O) and log(Ar/S) ratios are found close to those measured in the
extragalactic HII regions and in blue compact galaxies where O is more abundant
by at least one order of magnitude. This strengthens the universality of the
Ar/O and Ar/S ratios and lends support to the existence of a universal IMF. The
abundance of the non-refractory element phosphorus [P/H] = - 2.31 (+/- 0.10)
confirms the low amount of chemical evolution in the DLA. This is the
measurement of P in the most metal-poor material and shows a subsolar [P/Fe] =
--0.27 value. The measured ratios [P/Si] = - 0.40 (+/- 0.13) and [P/S] = - 0.33
(+/- 0.13) provide evidence for a mild odd-even effect. Finally, a stringent
upper limit to the population of the 3P_1 level in the ground state of OI is
derived, which provides a lower limit to the physical dimensions of the zabs =
3.3901 system of L > 7 pc.

</DOC>
<DOC>
<DOCNO> 178833 </DOCNO>
The Next Yukawa Phase of QCD at RHIC


  QCD predicts the existence of a new partonic Yukawa phase above a critical
temperature $T_c\sim 150$ MeV. I review some of the key observables which will
be used in heavy ion reactions to search for this new phase at RHIC.
Systematics of collective observables ($N_{ch},E_\perp)$, flow patterns, meson
interferometry, jet quenching, and $J/\psi$ suppression are discussed. This
talk is updated with the first data from RHIC.

</DOC>
<DOC>
<DOCNO> 9528 </DOCNO>
Two-Roton Bound State in the Fractional Quantum Hall Effect


  The true nature of the lowest-energy, long-wavelength neutral excitation of
the fractional quantum Hall effect has been a long outstanding problem. In this
Letter, we establish that it is a two-roton bound state.

</DOC>
<DOC>
<DOCNO> 68099 </DOCNO>
Lepton Flavor Violation: Constraints from exotic muon to electron


  The exotic neutrinoless $\mu^- - e^-$ nuclear conversion is studied within
the conventional extensions of the standard model as well as in the minimal
supersymmetric (SUSY) models with and without R-parity conservation. The
dependence of the $\mu^- - e^-$ conversion rates on the nucleon and nuclear
structure is consistently taken into account. Using our calculated transition
matrix elements and the available experimental data on the branching ratio
$R_{\mu e^-}$ for $^{48}$Ti and $^{208}$Pb as well as the expected experimental
sensitivity for $^{27}$Al employed as a target in the planned at Brookhaven
$\mu^--e^-$ conversion (MECO) experiment, we extract very severe constraints
for the flavor violation parameters. We especially emphasize on the constraints
resulting for SUSY R-parity violating parameters.

</DOC>
<DOC>
<DOCNO> 68052 </DOCNO>
Baryon Diffusion Constant in Hot and Dense Hadronic Matter Based on an


  We generate the statistical ensembles in equilibrium with fixed temperature
and chemical potential by imposing periodic boundary condition to the
simulation of URASiMA(Ultra-Relativistic AA collision Simulator based on
Multiple Scattering Algorithm). By using the generated ensembles, we
investigate the temperature dependence and the chemical potential dependence of
the nucleon diffusion constant of a dense and hot hadronic matter.

</DOC>
<DOC>
<DOCNO> 68715 </DOCNO>
Comment on Casimir energy for spherical boundaries


  It is shown that recent criticism by C. R. Hagen (hep-th/9902057) questioning
the validity of stress tensor treatments of the Casimir energy for space
divided into two parts by a spherical boundary is without foundation.

</DOC>
<DOC>
<DOCNO> 150657 </DOCNO>
Level truncation and the tachyon in open bosonic string field theory


  The tachyonic instability of the open bosonic string is analyzed using the
level truncation approach to string field theory. We have calculated all terms
in the cubic action of the string field theory describing zero-momentum
interactions of up to level 20 between scalars of level 10 or less. These
results are used to study the tachyon effective potential and the
nonperturbative stable vacuum. We find that the energy gap between the unstable
and stable vacua converges much more quickly than the coefficients of the
effective tachyon potential. By including fields up to level 10, 99.91% of the
energy from the bosonic D-brane tension is cancelled in the nonperturbative
stable vacuum. It appears that the perturbative expansion of the effective
tachyon potential around the unstable vacuum has a small but finite radius of
convergence. We find evidence for a critical point in the tachyon effective
potential at a small negative value of the tachyon field corresponding to this
radius of convergence. We study the branch structure of the effective potential
in the vicinity of this point and speculate that the tachyon effective
potential is globally nonnegative.

</DOC>
<DOC>
<DOCNO> 85269 </DOCNO>
Vector-like Einstein's equations for D-dimensional spherical gravity


  We demonstrate how the Einstein's equations for the $D$-dimensional spherical
gravity can be written in the covariant vector-like form. These equations
reveal easily the causal structure of curved spherically symmetric manifolds
and may appear useful in investigation of different models of brane universes.

</DOC>
<DOC>
<DOCNO> 11293 </DOCNO>
High-field limit of the Vlasov-Poisson-Fokker-Planck system: A


  A reduced drift-diffusion (Smoluchowski-Poisson) equation is found for the
electric charge in the high-field limit of the Vlasov-Poisson-Fokker-Planck
system, both in one and three dimensions. The corresponding electric field
satisfies a Burgers equation. Three methods are compared in the one-dimensional
case: Hilbert expansion, Chapman-Enskog procedure and closure of the hierarchy
of equations for the moments of the probability density. Of these methods, only
the Chapman-Enskog method is able to systematically yield reduced equations
containing terms of different order.

</DOC>
<DOC>
<DOCNO> 169825 </DOCNO>
Quantum authentication and key distribution using catalysis


  Starting from Barnum's recent proposal to use entanglement and catalysis for
quantum secure identification [quant-ph/9910072], we describe a protocol for
quantum authentication and authenticated quantum key distribution. We argue
that our scheme is secure even in the presence of an eavesdropper who has
complete control over both classical and quantum channels.

</DOC>
<DOC>
<DOCNO> 122698 </DOCNO>
A Strategy for Identifying the Grid Stars for the Space Interferometry


  We present a strategy to identify several thousand stars that are
astrometrically stable at the micro-arcsecond level for use in the SIM (Space
Interferometry Mission) astrometric grid. The requirements on the grid stars
make this a rather challenging task. Taking a variety of considerations into
account we argue for K giants as the best type of stars for the grid, mainly
because they can be located at much larger distances than any other type of
star due to their intrinsic brightness. We show that it is possible to identify
suitable candidate grid K giants from existing astrometric catalogs. However,
double stars have to be eliminated from these candidate grid samples, since
they generally produce much larger astrometric jitter than tolerable for the
grid. The most efficient way to achieve this is probably by means of a radial
velocity survey. To demonstrate the feasibility of this approach, we repeatedly
measured the radial velocities for a pre-selected sample of 86 nearby Hipparcos
K giants with precisions of 5-8 m/s. The distribution of the intrinsic radial
velocity variations for the bona-fide single K giants shows a maximum around 20
m/s, which is small enough not to severely affect the identification of stellar
companions around other K giants. We use the results of our observations as
input parameters for Monte-Carlo simulations on the possible design of a radial
velocity survey of all grid stars. Our favored scenario would result in a grid
which consists to 68% of true single stars and to 32% of double or multiple
stars with periods mostly larger than 200 years, but only 3.6% of all grid
stars would display astrometric jitter larger than 1 microarcsecond. This
contamination level is probably tolerable.

</DOC>
<DOC>
<DOCNO> 99874 </DOCNO>
Quantum Computation by Geometrical Means


  A geometrical approach to quantum computation is presented, where a
non-abelian connection is introduced in order to rewrite the evolution operator
of an energy degenerate system as a holonomic unitary. For a simple geometrical
model we present an explicit construction of a universal set of gates,
represented by holonomies acting on degenerate states.

</DOC>
<DOC>
<DOCNO> 150811 </DOCNO>
Chapline-Manton interaction vertices and Hamiltonian BRST cohomology


  Consistent interactions between Yang-Mills gauge fields and an abelian 2-form
are investigated by using a Hamiltonian cohomological procedure. It is shown
that the deformation of the BRST charge and the BRST-invariant Hamiltonian of
the uncoupled model generates the Yang-Mills Chern-Simons interaction term. The
resulting interactions deform both the gauge transformations and their algebra,
but not the reducibility relations.

</DOC>
<DOC>
<DOCNO> 120604 </DOCNO>
Attenuation of Beaming Oscillations Near Neutron Stars


  Observations with RXTE have revealed kilohertz quasi-periodic brightness
oscillations (QPOs) from nearly twenty different neutron-star low-mass X-ray
binaries (LMXBs). These frequencies often appear as a pair of kilohertz QPOs in
a given power density spectrum. In many models the higher-frequency of these
QPOs is a beaming oscillation at the frequency of a nearly circular orbit at
some radius near the neutron star. In such models it is expected that there
will also be beaming oscillations at the stellar spin frequency and at
overtones of the orbital frequency, but no strong QPOs have been detected at
these frequencies. We therefore examine the processes that can attenuate
beaming oscillations near neutron stars, and in doing so extend the work on
this subject that was initiated by the discovery of lower-frequency QPOs from
LMXBs. Among our main results are (1)in a spherical scattering cloud, all
overtones of rotationally modulated beaming oscillations are attenuated
strongly, not just the even harmonics, and (2)it is possible to have a
relatively high-amplitude modulation near the star at, e.g., the stellar spin
frequency, even if no peak at that frequency is detectable in a power density
spectrum taken at infinity. We discuss the application of these results to
modeling of kilohertz QPOs.

</DOC>
<DOC>
<DOCNO> 122344 </DOCNO>
Synthetic Doppler maps of gaseous flows in semidetached binaries based


  We present synthetic Doppler maps of gaseous flows in semidetached binaries
based on the results of 3D gas dynamical simulations. Using of gas dynamical
calculations alongside with Doppler tomography technique permits to identify
main features of the flow on the Doppler maps without solution of ill-posed
inverse problem. Comparison of synthetic tomograms with observations makes
possible both to refine the gas dynamical model and to interpret the
observational data.

</DOC>
<DOC>
<DOCNO> 170551 </DOCNO>
Quantum Computation Relative to Oracles


  The study of the power and limitations of quantum computation remains a major
challenge in complexity theory. Key questions revolve around the quantum
complexity classes EQP, BQP, NQP, and their derivatives. This paper presents
new relativized worlds in which (i) co-RP is not a subset of NQE, (ii) P=BQP
and UP=EXP, (iii) P=EQP and RP=EXP, and (iv) EQP is not a subset of the union
of Sigma{p}{2} and Pi{p}{2}. We also show a partial answer to the question of
whether Almost-BQP=BQP.

</DOC>
<DOC>
<DOCNO> 178665 </DOCNO>
Seniority isomerism in proton-rich N=82 isotones and its indication to


  The $10^+$ and $27/2^-$ isomers of the $Z>64$, $N=82$ nuclei are investigated
in the shell model framework. We derive an extended seniority reduction formula
for the relevant $E2$ transition strengths. Based on the extended formula, as
well as on the approximate degeneracy among the $0h_{11/2}$, $2s_{1/2}$ and
$1d_{3/2}$ orbits, we argue that the $B(E2)$ data require the $^{146}$Gd core
excitation. The energy levels of both parities and the $B(E2)$ values are
simultaneously reproduced by a multi-$j$ shell model calculation with the MSDI,
if the excitations from $(0g_{7/2}1d_{5/2})$ to $(0h_{11/2}2s_{1/2}1d_{3/2})$
are taken into account.

</DOC>
<DOC>
<DOCNO> 84598 </DOCNO>
Post-Newtonian Frames of Reference


  A general theory of frames of reference proposed in a preceding publication
is considered here in the framework of the post-Newtonian approximation,
assuming that the frame of reference is centered on a time-like geodesic. The
problem of taking into account the rotation of the frame of reference, which is
usually ignored or incorrectly oversimplified, is here discussed in detail and
solved.

</DOC>
<DOC>
<DOCNO> 116840 </DOCNO>
High-intensity single-bunch electron beam generation with the 38 MeV


  The characteristics of the high-intensity single-bunch electron beam of the
38 MeV L-band electron linac at the Institute of Scientific and Industrial
Research in Osaka University were investigated.

</DOC>
<DOC>
<DOCNO> 83273 </DOCNO>
A Compact Architecture for Dialogue Management Based on Scripts and


  We describe an architecture for spoken dialogue interfaces to semi-autonomous
systems that transforms speech signals through successive representations of
linguistic, dialogue, and domain knowledge. Each step produces an output, and a
meta-output describing the transformation, with an executable program in a
simple scripting language as the final result. The output/meta-output
distinction permits perspicuous treatment of diverse tasks such as resolving
pronouns, correcting user misconceptions, and optimizing scripts.

</DOC>
<DOC>
<DOCNO> 40262 </DOCNO>
The Longitudinal Polarimeter at HERA


  The design, construction and operation of a Compton back-scattering laser
polarimeter at the HERA storage ring at DESY are described. The device measures
the longitudinal polarization of the electron beam between the spin rotators at
the HERMES experiment with a fractional systematic uncertainty of 1.6%. A
measurement of the beam polarization to an absolute statistical precision of
0.01 requires typically one minute when the device is operated in the
multi-photon mode. The polarimeter also measures the polarization of each
individual electron bunch to an absolute statistical precision of 0.06 in
approximately five minutes. It was found that colliding and non-colliding
bunches can have substantially different polarizations. This information is
important to the collider experiments H1 and ZEUS for their future
longitudinally polarized electron program because those experiments use the
colliding bunches only.

</DOC>
<DOC>
<DOCNO> 100070 </DOCNO>
On threefolds covered by lines


  A classification theorem is given of projective threefolds that are covered
by a two-dimensional family of lines, but not by a higher dimensional family.

</DOC>
<DOC>
<DOCNO> 70814 </DOCNO>
Cooling of Hybrid Neutron Stars and Hypothetical Self-bound Objects with


  We study the consequences of superconducting quark cores (with
color-flavor-locked phase as representative example) for evolution of
temperature profiles and the cooling curves in quark-hadron hybrid stars and in
hypothetical self-bounded objects having no a hadron shell (quark core neutron
stars). The quark gaps are varied from 0 to $\Delta_q =50$ MeV. For hybrid
stars we find time scales of $1\div5$, $5\div10$ and $50\div100$ years for the
formation of a quasistationary temperature distribution in the cases $\Delta_q
=0$, 0.1 MeV and $\gsim$ 1 MeV, respectively. These time scales are governed by
the heat transport within quark cores for large diquark gaps ($\Delta \gsim$ 1
MeV) and within the hadron shell for small diquark gaps ($\Delta \lsim 0.1$
MeV). For quark core neutron stars we find a time scale $\simeq 300$ years for
the formation of a quasistationary temperature distribution in the case $\Delta
\gsim$ 10 MeV and a very short one for $\Delta \lsim$ 1 MeV. If hot young
compact objects will be observed they can be interpreted as manifestation of
large gap color superconductivity. Depending on the size of the pairing gaps,
the compact star takes different paths in the ${lg}T_s $ vs. ${lg} t$ diagram
where $T_s$ is the surface temperature. Compared to the corresponding hadronic
model which well fits existing data the model for the hybrid neutron star (with
a large diquark gap) shows too fast cooling. The same conclusion can be drawn
for the corresponding self-bound objects.

</DOC>
<DOC>
<DOCNO> 170307 </DOCNO>
The Time-Asymmetry and the Entropy Gap


  The universe time-asymmetry is essentially produced by its low-entropy
unstable initial state. Using quanlitative arguments, Paul Davies has
demonstrated that the universe expansion may diminish the entropy gap,
therefore explaining its low-entropy state, with respect to the maximal
possible entropy at any time. This idea is implemented in a qualitative
way\thinspace in a simple homogeneous model. Some rough coincidence with
observational data are found

</DOC>
<DOC>
<DOCNO> 84943 </DOCNO>
Covariant and locally Lorentz-invariant varying speed of light theories


  We propose definitions for covariance and local Lorentz invariance applicable
when the speed of light $c$ is allowed to vary. They have the merit of
retaining only those aspects of the usual definitions which are invariant under
unit transformations, and which can therefore legitimately represent the
outcome of an experiment. We then discuss some possibilities for invariant
actions governing the dynamics of such theories. We consider first the
classical action for matter fields and the effects of a changing $c$ upon
quantization. We discover a peculiar form of quantum particle creation due to a
varying $c$. We then study actions governing the dynamics of gravitation and
the speed of light. We find the free, empty-space, no-gravity solution, to be
interpreted as the counterpart of Minkowksi space-time, and highlight its
similarities with Fock-Lorentz space-time. We also find flat-space string-type
solutions, in which near the string core $c$ is much higher. We label them
fast-tracks and compare them with gravitational wormholes. We finally discuss
general features of cosmological and black hole solutions, and digress on the
meaning of singularities in these theories.

</DOC>
<DOC>
<DOCNO> 9291 </DOCNO>
Addendum to ``Multichannel Kondo screening in a one-dimensional


  This is an addendum to our previous work cond-mat/9705048 (published in
Europhysics Letters 41, 213 (1998)), clarifying the construction of the
two-particle scattering matrices used for studying the magnetic impurity
behavior in a multichannel correlated host.

</DOC>
<DOC>
<DOCNO> 151342 </DOCNO>
CPT anomaly in two-dimensional chiral U(1) gauge theories


  The CPT anomaly, which was first seen in perturbation theory for certain
four-dimensional chiral gauge theories, is also present in the exact result for
a class of two-dimensional chiral U(1) gauge theories on the torus.
Specifically, the chiral determinant for periodic fermion fields changes sign
under a CPT transformation of the background gauge field. There is, in fact, an
anomaly of Lorentz invariance, which allows for the CPT theorem to be
circumvented.

</DOC>
<DOC>
<DOCNO> 174532 </DOCNO>
Spectral Measurements of Neutrons from Pb, W, and Na Targets Irradiated


  Preliminary results of neutron spectra measurements from Pb, W, and Na
targets irradiated by 0.8 and 1.6 GeV protons are presented. Measurements have
been carried out using the proton beam extracted from the ITEP synchrotron and
the TOF technique. Neutron registration has been carried out using BICRON
MAB-511 liquid scintillation counters. Spectra measured at angles of 30, 60,
90, 120, and 150 degrees have been compared with results of their simulation
using the LAHET code system and the code CEM2k. The results are of interest
both from data gathering viewpoint and as a benchmark of the up-to-the-date
predictive powers of codes applied to design the hybrid Accelerator Driven
Systems (ADS) using lead or lead-bismuth targets and sodium-cooled targets.

</DOC>
<DOC>
<DOCNO> 68629 </DOCNO>
Leptoquark signal from global analysis


  Data from HERA, LEP and the Tevatron, as well as from low energy experiments
are used to constrain the Yukawa couplings for scalar and vector leptoquarks in
the Buchmuller-Ruckl-Wyler effective model. In the limit of very high
leptoquark masses constraints on the coupling to the mass ratio l/M are derived
using the contact-interaction approximation. For finite masses the coupling
limits are studied as a function of the leptoquark mass. Some leptoquark models
are found to describe the existing experimental data much better than the
Standard Model. Increase in the global probability observed for models
including S_1 or ~V_o leptoquark production/exchange corresponds to more than a
3 sigma effect. Assuming that a real leptoquark signal is observed, calculated
is an allowed region in the l-M plane. The leptoquark signal is mostly
resulting from the new data on the atomic parity violation in cesium, but is
also supported by recent LEP2 measurements, unitarity violation in the CKM
matrix and HERA high-Q^2 results.

</DOC>
<DOC>
<DOCNO> 69727 </DOCNO>
Interference pattern of the Coulomb and the strong Van der Waals forces


  In order to confirm the strong Van der Waals force in the nucleon-nucleon
interaction, it is proposed to measure precisely the angular distribution of
the cross section of the low energy ($T_{lab}=20 \sim 30MeV.$) proton-proton
scattering. By using the spectrum of the long range interaction obtained from
the analysis of the phase shift data of the S-wave of the p-p scattering, a
characteristic interference pattern, which arises from the repulsive Coulomb
and the attractive strong Van der Waals forces, is predicted. The pattern has a
dip at $theta_{c.m.}=14^{\circ}$ with the depth around one per cent.

</DOC>
<DOC>
<DOCNO> 102615 </DOCNO>
Birational Weyl group action arising from a nilpotent Poisson algebra


  We propose a general method to realize an arbitrary Weyl group of Kac-Moody
type as a group of birational canonical transformations, by means of a
nilpotent Poisson algebra. We also give a Lie theoretic interpretation of this
realization in terms of Kac-Moody Lie algebras and Kac-Moody groups.

</DOC>
<DOC>
<DOCNO> 9741 </DOCNO>
Deterministic walks in random media: evidence of generic scale


  Deterministic walks over a random set of points in one and two dimensions
(d=1,2) are considered. Points (``cities'') are randomly scattered in R^d
following a uniform distribution. A walker (a ``tourist''), at each time step,
goes to the nearest neighbor city that has not been visited in the past \tau
steps. Each initial city leads to a trajectory composed of a transient part and
a final p-cycle attractor. The distribution of transient times, p-cycles and
number of cities per attractor are studied. It is shown numerically that
transient times (for d=1,2) follow a Poisson law with a $\tau$ dependent decay
but the density of p-cycles follows a power law D(p) \propto p^{-\alpha(\tau)}
for d=2. For large \tau, the expoent tends to \alpha ~ 5/2. Some analytical
results are given for the d=1 case. Since the power law is robust and does not
depend on free parameters, this system presents ``generic scale invariance''.
Applications to animal exploratory behavior and other local minimization
problems are suggested.

</DOC>
<DOC>
<DOCNO> 100773 </DOCNO>
Absolutely Abnormal Numbers


  Despite the fact that almost all real numbers are absolutely normal---that
is, the digits in their expansions to any base occur in all possible
configurations with the expected frequency---not one specific example of an
absolutely normal number is known. In this note we investigate the opposite
extreme, numbers that are normal to no base whatsoever, and we succeed in
writing down explicitly such a number.

</DOC>
<DOC>
<DOCNO> 118840 </DOCNO>
Extremely Red Objects from the NICMOS/HST Parallel Imaging Survey


  We present a catalog of extremely red objects discovered using the NICMOS/HST
parallel imaging database and ground-based optical follow-up observations.
Within an area of 16 square arc-minutes, we detect 15 objects with $\rm R -
F160W > 5$ and $\rm F160W < 21.5$. We have also obtained K-band photometry for
a subset of the 15 EROs. All of the $\rm R - F160W$ selected EROs imaged at
K-band have $\rm R - K > 6$. Our objects have $\rm F110W - F160W$ colors in the
range of 1.3 - 2.1, redder than the cluster ellipticals at $z \sim 0.8$ and
nearly 1 magnitude redder than the average population selected from the F160W
images at the same depth. In addition, among only 22 NICMOS pointings, we
detected two groups or clusters in two fields, each contains 3 or more EROs,
suggesting that extremely red galaxies may be strongly clustered. At bright
magnitudes with $\rm F160W < 19.5$, the ERO surface density is similar to what
has been measured by other surveys. At the limit of our sample, F160W = 21.5,
our measured surface density is 0.94$\pm 0.24$ arcmin^{-2}. Excluding the two
possible groups/clusters and the one apparently stellar object, reduces the
surface density to 0.38$\pm 0.15$ arcmin^{-2}.

</DOC>
<DOC>
<DOCNO> 80687 </DOCNO>
Chiral Anomaly for a New Class of Lattice Dirac Operators


  A new class of lattice Dirac operators which satisfy the index theorem have
been recently proposed on the basis of the algebraic relation
$\gamma_{5}(\gamma_{5}D) + (\gamma_{5}D)\gamma_{5} =
2a^{2k+1}(\gamma_{5}D)^{2k+2}$. Here $k$ stands for a non-negative integer and
$k=0$ corresponds to the ordinary Ginsparg-Wilson relation. We analyze the
chiral anomaly and index theorem for all these Dirac operators in an explicit
elementary manner. We show that the coefficient of anomaly is independent of a
small variation in the parameters $r$ and $m_{0}$, which characterize these
Dirac operators, and the correct chiral anomaly is obtained in the (naive)
continuum limit $a\to 0$.

</DOC>
<DOC>
<DOCNO> 120850 </DOCNO>
Fast Algorithms and Efficient Statistics: Density Estimation in Large


  In this paper, we outline the use of Mixture Models in density estimation of
large astronomical databases. This method of density estimation has been known
in Statistics for some time but has not been implemented because of the large
computational cost. Herein, we detail an implementation of the Mixture Model
density estimation based on multi-resolutional KD-trees which makes this
statistical technique into a computationally tractable problem. We provide the
theoretical and experimental background for using a mixture model of Gaussians
based on the Expectation Maximization (EM) Algorithm. Applying these analyses
to simulated data sets we show that the EM algorithm - using the AIC penalized
likelihood to score the fit - out-performs the best kernel density estimate of
the distribution while requiring no ``fine--tuning'' of the input algorithm
parameters. We find that EM can accurately recover the underlying density
distribution from point processes thus providing an efficient adaptive
smoothing method for astronomical source catalogs. To demonstrate the general
application of this statistic to astrophysical problems we consider two cases
of density estimation: the clustering of galaxies in redshift space and the
clustering of stars in color space. From these data we show that EM provides an
adaptive smoothing of the distribution of galaxies in redshift space
(describing accurately both the small and large-scale features within the data)
and a means of identifying outliers in multi-dimensional color-color space
(e.g. for the identification of high redshift QSOs). Automated tools such as
those based on the EM algorithm will be needed in the analysis of the next
generation of astronomical catalogs (2MASS, FIRST, PLANCK, SDSS) and ultimately
in in the development of the National Virtual Observatory.

</DOC>
<DOC>
<DOCNO> 151437 </DOCNO>
Landau levels on a torus


  Landau levels have represented a very rich field of research, which has
gained widespread attention after their application to quantum Hall effect. In
a particular gauge, the holomorphic gauge, they give a physical implementation
of Bargmann's Hilbert space of entire functions. They have also been recognized
as a natural bridge between Feynman's path integral and Geometric Quantization.
We discuss here some mathematical subtleties involved in the formulation of the
problem when one tries to study quantum mechanics on a finite strip of sides
L_1, L_2 with a uniform magnetic field and periodic boundary conditions. There
is an apparent paradox here: infinitesimal translations should be associated to
canonical operators [p_x,p_y] \propto i\hslash B, and, at the same time, live
in a Landau level of finite dimension B L_1L_2/(hc/e), which is impossible from
Wintner's theorem. The paper shows the way out of this conundrum.

</DOC>
<DOC>
<DOCNO> 68918 </DOCNO>
On the Applicability of Weak-Coupling Results in High Density QCD


  Quark matter at asymptotically high baryon chemical potential is in a color
superconducting state characterized by a gap Delta. We demonstrate that
although present weak-coupling calculations of Delta are formally correct for
mu -> Infinity, the contributions which have to this point been neglected are
large enough that present results can only be trusted for mu >> mu_c ~ 10^8
MeV. We make this argument by using the gauge dependence of the present
calculation as a diagnostic tool. It is known that the present calculation
yields a gauge invariant result for mu -> Infinity; we show, however, that the
gauge dependence of this result only begins to decrease for mu > mu_c, and
conclude that the result can certainly not be trusted for mu < mu_c. In an
appendix, we set up the calculation of the influence of the Meissner effect on
the magnitude of the gap. This contribution to Delta is, however, much smaller
than the neglected contributions whose absence we detect via the resulting
gauge dependence.

</DOC>
<DOC>
<DOCNO> 8285 </DOCNO>
The Specific Heat of a Trapped Fermi Gas: an Analytical Approach


  We find an analytical expression for the specific heat of a Fermi gas in a
harmonic trap using a semi-classical approximation. Our approximation is valid
for kT>hw and in this range it is shown to be highly accurate. We comment on
the semi-classical approximation, presenting an explanation for this high
accuracy.

</DOC>
<DOC>
<DOCNO> 121698 </DOCNO>
Discovery of an Extended Dust Emission around IRAS 18576+0341 (AFGL


  We report detection of an extended mid-infrared emission from \iras
18576+0341 (AFGL 2298). The object shows a dusty circumstellar shell that has
diameter of $\age 7\arcsec$ at 10.3 and 18.0 $\um$. The dust nebula shows two
emission peaks concentrically elongated and symmetrically oriented on the
opposite sides of the third, central peak, which appears to be the central star
of the system. The observed mid-infrared morphology indicates that the
circumstellar dust shell has an equatorially-enhanced material distribution,
which is a common signature of stellar objects that have experienced mass loss.
Radiative transfer model calculations suggest that the central star is an
extremely bright ($\lstar = 10^{6.4} \lsun$) star at a distance of about 10
kpc: this object is best described as a new luminous blue variable candidate.
The circumstellar dust shell seems to have been generated by an
equatorially-enhanced mass loss process with ${\dot M} \ge 6.8 \times 10^{-6}
\msun$ yr$^{-1}$ and ${\dot M}_{\rm pole}/{\dot M}_{\rm eq} \sim 0.5$.

</DOC>
<DOC>
<DOCNO> 10011 </DOCNO>
Testing the Kibble-Zurek Scenario with Annular Josephson Tunnel


  In parallel with Kibble's description of the onset of phase transitions in
the early universe, Zurek has provided a simple picture for the onset of phase
transitions in condensed matter systems, strongly supported by agreement with
experiments in He3. In this letter we show how experiments with annular
Josephson tunnel Junctions can and do provide further support for this
scenario.

</DOC>
<DOC>
<DOCNO> 8189 </DOCNO>
Random-mass Dirac fermions in an imaginary vector potential:


  One dimensional system of Dirac fermions with a random-varying mass is
studied by the transfer-matrix methods which we developed recently. We
investigate the effects of nonlocal correlation of the spatial-varying Dirac
mass on the delocalization transition. Especially we numerically calculate both
the "typical" and "mean" localization lengths as a function of energy and the
correlation length of the random mass. To this end we introduce an imaginary
vector potential as suggested by Hatano and Nelson and solve the eigenvalue
problem. Numerical calculations are in good agreement with the results of the
analytical calculations.

</DOC>
<DOC>
<DOCNO> 10099 </DOCNO>
Low-temperature specific heat of La0.78Pb0.22MnO3-d manganite


  The specific heat of the perovskite manganite La0.78Pb0.22MnO3-d was measured
from 0.5 to 25 K. The results yield values of the electronic density of states,
the Debye temperature, and the spin-wave stiffness constant of the compound.
The magnetic contribution was found to be consistent with the existence of a
gap in the spin-wave spectrum, and a phonon term in T^5 was needed to fit the
data.

</DOC>
<DOC>
<DOCNO> 10943 </DOCNO>
Comment on ``Critical behavior of a two-species reaction-diffusion


  In a recent paper, de Freitas et al. [Phys. Rev. E 61, 6330 (2000)] presented
simulational results for the critical exponents of the two-species
reaction-diffusion system A + B -> 2B and B -> A in dimension d = 1. In
particular, the correlation length exponent was found as \nu = 2.21(5) in
contradiction to the exact relation \nu = 2/d. In this Comment, the symmetry
arguments leading to exact critical exponents for the universality class of
this reaction-diffusion system are concisely reconsidered.

</DOC>
<DOC>
<DOCNO> 170423 </DOCNO>
Bell's Theorem and Random Variables


  Bell's theorem states that quantum correlation function of two spins can not
be represented as an expectation value of two classical random variables. Spin
is described in Bell's model by a single scalar random variable. We discuss
another classical model of spin in which spin is described by a triple of
classical random variables. It is shown that in this model the quantum
correlation function can be represented as the expectation value of classical
random variables. Implications of this result to the problem of local causality
of quantum mechanics and relations with problems of moments are briefly
mentioned.

</DOC>
<DOC>
<DOCNO> 102586 </DOCNO>
Computing Triangulations of Mapping Tori of Surface Homeomorphisms


  We present the mathematical background of a software package that computes
triangulations of mapping tori of surface homeomorphisms, suitable for Jeff
Weeks's program SnapPea. It consists of two programs. jmt computes
triangulations and prints them in a human-readable format. jsnap converts this
format into SnapPea's triangulation file format and may be of independent
interest because it allows for quick and easy generation of input for SnapPea.
  As an application, we obtain a new solution to the restricted conjugacy
problem in the mapping class group.

</DOC>
<DOC>
<DOCNO> 170228 </DOCNO>
Quantum key distribution in the Holevo limit


  A theorem by Shannon and the Holevo theorem impose that the efficiency of any
protocol for quantum key distribution, $\cal E$, defined as the number of
secret (i.e., allowing eavesdropping detection) bits per transmitted bit plus
qubit, is ${\cal E} \le 1$. The problem addressed here is whether the limit
${\cal E} =1$ can be achieved. It is showed that it can be done by splitting
the secret bits between several qubits and forcing Eve to have only a
sequential access to the qubits, as proposed by Goldenberg and Vaidman. A
protocol with ${\cal E} =1$ based on polarized photons and in which Bob's state
discrimination can be implemented with linear optical elements is presented.

</DOC>
<DOC>
<DOCNO> 120796 </DOCNO>
Disk Formation by AGB Winds in Dipole Magnetic Fields


  We present a simple, robust mechanism by which an isolated star can produce
an equatorial disk. The mechanism requires that the star have a simple dipole
magnetic field on the surface and an isotropic wind acceleration mechanism. The
wind couples to the field, stretching it until the field lines become mostly
radial and oppositely directed above and below the magnetic equator, as occurs
in the solar wind. The interaction between the wind plasma and magnetic field
near the star produces a steady outflow in which magnetic forces direct plasma
toward the equator, constructing a disk. In the context of a slow (10 km/s)
outflow (10^{-5} M_sun/yr) from an AGB star, MHD simulations demonstrate that a
dense equatorial disk will be produced for dipole field strengths of only a few
Gauss on the surface of the star. A disk formed by this model can be
dynamically important for the shaping of Planetary Nebulae.

</DOC>
<DOC>
<DOCNO> 152227 </DOCNO>
Tachyon Condensation in Noncommutative Gauge Theory


  We show that the decay of the D2-\bar{D2} system with large worldvolume
magnetic fields can be described in noncommutative gauge theory. Tachyon
condensation in this system describes the annihilation of D2-\bar{D2} into
$D0$-branes. From the 2+1 dimensional point of view, this is the decay of a
nonabelian magnetic flux into vortices. The semiclassical approximation is
valid over a long period of the decay. Our analysis allows us to clarify
earlier results in the literature related to tachyon condensation and
noncommutative gauge theory.

</DOC>
<DOC>
<DOCNO> 120650 </DOCNO>
The First Hours of a Core Collapse Supernova


  New two-dimensional, high-resolution calculations of a core collapse
supernova in a 15 Msol blue supergiant are presented, which cover the entire
evolution from shock revival until the first few hours of the explosion.
Explosive nucleosynthesis, its dependence upon convective mixing during the
first second of the evolution and the growth of Rayleigh-Taylor instabilities
at the composition interfaces of the progenitor star are all modeled
consistently and allow for a comparison with observational data. We confirm our
earlier findings, that the perturbations induced by neutrino driven convection
are sufficiently strong to seed large-scale Rayleigh-Taylor mixing and to
destroy the onion-shell structure of the stellar He-core. As in our earlier
calculations, the strong deceleration of the nickel clumps in the layers
adjacent to the He/H interface suggests that the high velocities of iron-group
elements observed in SN 1987A cannot be explained on the basis of currently
favored progenitor models. Possible solutions to this dilemma and the
implications of the mixing for type Ib explosions are briefly discussed.

</DOC>
<DOC>
<DOCNO> 70735 </DOCNO>
Confinement and Flavor Symmetry Breaking via Monopole Condensation


  We discuss dynamics of N=2 supersymmetric SU(n_c) gauge theories with n_f
quark hypermultiplets. Upon N=1 perturbation of introducing a finite mass for
the adjoint chiral multiplet, we show that the flavor U(n_f) symmetry is
dynamically broken to U(r) \times U(n_f-r), where r\leq [n_f/2] is an integer.
This flavor symmetry breaking occurs due to the condensates of magnetic degrees
of freedom which acquire flavor quantum numbers due to the quark zero modes. We
briefly comment on the USp(2n_c) gauge theories. This talk is based on works
with Giuseppe Carlino and Ken Konishi, hep-th/0001036 and hep-th/0005076.

</DOC>
<DOC>
<DOCNO> 121231 </DOCNO>
Evolutionary Self-Energy-Loss Effects in Compact Binary Systems:


  The spin-down of a millisecond pulsar in a compact binary system leads to
self-energy losses, that cause the binary's orbital period to increase (the
effect being of first post-Newtonian (1PN) order). If the pulsar's
period-derivative is not exceedingly small, this effect can become measurable
in long-term high-precision timing measurements of the binary's orbital motion.
We use rotating compressible spheroids to obtain an approximate, explicit
expression for the orbital period derivative, due to spin-down, valid to 1PN
order. This expression can be used to observationally constrain the pulsar's
moment of inertia, and, combined with other observations, the high-density
equation of state of compact stars. We apply our expression to representative
models of millisecond pulsars in binary systems and demonstrate the importance
of including higher-order rotational effects as well as the importance of the
choice of equation of state, which both have been neglected, so far, in the
literature. The computed increase in orbital period is larger, by as much as
32%, when the higher-order rotational effects are included, while it can change
by more than a factor of two between different plausible equations of state.

</DOC>
<DOC>
<DOCNO> 119837 </DOCNO>
Cold gas and star formation in a merging galaxy sequence


  We explore the evolution of the cold gas and star-formation activity during
galaxy interactions, using a merging galaxy sequence comprising both pre- and
post-mergers. Data for this study come from the literature but supplemented by
new radio observations presented here. Firstly, we confirm that the
star-formation efficiency (SFE) increases close to nuclear coalescence. At
post-merger stages there is evidence that the SFE declines to values typical of
ellipticals. This trend can be attributed to M(H_2) depletion due to
interaction induced star-formation. However, there is significant scatter,
likely to arise from differences in the interaction details of individual
systems. Secondly, we find that the central molecular hydrogen surface density,
increases close to the final stages of the merging of the two nuclei. Such a
trend is also predicted by numerical simulations. Furthermore, there is
evidence for a decreasing fraction of cold gas mass from early interacting
systems to merger remnants, attributed to gas conversion into other forms. The
evolution of the total-radio to blue-band luminosity ratio, reflecting the
disk+nucleus star-formation activity, is also investigated. Although this ratio
is on average higher than that of isolated spirals, we find a marginal increase
along the merging sequence, attributed to the relative insensitivity of disk
star-formation to interactions. However, a similar result is also obtained for
the nuclear radio emission, although galaxy interactions are believed to
significantly affect the activity in the central galaxy regions. Finally, we
find that the FIR--radio flux ratio distribution of interacting galaxies is
consistent with star-formation being the main energising source.

</DOC>
<DOC>
<DOCNO> 10693 </DOCNO>
Triple approach to determination of the c-axis penetration depth in


  The c-axis penetration depth $\lambda_c$ in
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ (BSCCO) single crystals as a function of
temperature has been determined using three high-frequency techniques, namely:
(i) measurements of the ac-susceptibility at a frequency of 100 kHz for
different sample alignments with respect to the ac magnetic field; (ii)
measurements of the surface impedance in both superconducting and normal states
of BSCCO crystals at 9.4 GHz; (iii) measurements of the surface barrier field
$H_J(T)\propto 1/\lambda_c(T)$ at which Josephson vortices penetrate into the
sample. Careful analysis of these measurements, including both numerical
solution of the electrodynamic problem of the magnetic field distribution in an
anisotropic plate at an arbitrary temperature and influence of defects in the
sample, has allowed us to estimate $\lambda_c(0)\approx 50 \mu$m in BSCCO
crystals overdoped with oxygen ($T_c\approx 84$ K) and $\lambda_c(0)\approx 150
\mu$m at the optimal doping level ($T_c\approx 90$ K). The results obtained by
different techniques are in reasonable agreement.

</DOC>
<DOC>
<DOCNO> 68883 </DOCNO>
Dynamics of superconducting strings with chiral currents


  We rederive, using an elementary formalism, the general solution to the
equations of motion for a superconducting string with a chiral (null) neutral
current, earlier obtained by Carter and Peter. We apply this solution to show
that the motion of such string loops is strictly periodic and analyze cusp-like
behavior and vorton solutions of arbitrary shape. We argue that this solution
can be used to approximately describe the dynamics of superconducting strings
with small non-chiral currents. We use this description to estimate the
electromagnetic radiation power from such strings.

</DOC>
<DOC>
<DOCNO> 170036 </DOCNO>
Bohmian description of a decaying quantum system


  We present a Bohmian description of a decaying quantum system. A particle is
initially confined in a region around the origin which is surrounded by a
repulsive potential barrier. The particle leaks out in time tunneling through
the barrier. We determine Bohm trajectories with which we can visualize various
features of the decaying system.

</DOC>
<DOC>
<DOCNO> 12325 </DOCNO>
A study of trapped Bose gas beyond mean-field theory


  We study the ground-state properties of dilute Bose gas confined to both
isotropic and anisotropic traps to assess the accuracy of Gross-Pitaevskii (GP)
theory. To go beyond GP approximation we use Huang-Yang theory of interatomic
interaction energy for hard-sphere Bose gas and use a variational method to
solve the resulting modified GP equation. We also make an analytic estimate of
the corrections due to higher-order terms in the interatomic interaction
energy. We find that the corrections are of the order of 1 percent. However,
there is a qualitative change in the density profile due to presence of
logarithimic term in the interaction energy for large N (number of atoms)

</DOC>
<DOC>
<DOCNO> 178639 </DOCNO>
Projected shell model study for the yrast-band structure of the


  A systematic study of the yrast-band structure for the proton-rich, even-even
mass-80 nuclei is carried out using projected shell model approach. We describe
the the energy spectra, transition quadrupole moments and gyromagnetic factors.
The observed variations in energy spectra and transition quadrupole moments in
this mass region are discussed in terms of the configuration mixing of the
projected deformed Nilsson states as a function of shell filling.

</DOC>
<DOC>
<DOCNO> 122814 </DOCNO>
The nature of dwarf nova outbursts


  We show that if the dwarf-nova disc instability model includes the effects of
heating by stream impact and tidal torque dissipation in the outer disc, the
calculated properties of dwarf-nova outbursts change considerably, and several
notorious deficiencies of this model are repaired. In particular: (1)
outside-in outbursts occur for mass transfer rates lower than in the standard
model as required by observations; (2) the presence of long (wide) and short
(narrow) outbursts with similar peak luminosities is a natural property of the
model. Mass-transfer fluctuations by factors ~ 2 can explain the occurrence of
both long and short outbursts above the cataclysmic variable period gap,
whereas below 2 hr only short normal outbursts are expected (in addition to
superoutbursts which are not dealt with in this article). With additional
heating by the stream and tidal torques, such fluctuations can also explain the
occurrence of both outside-in and inside-out outbursts in SS Cyg and similar
systems. The occurrence of outside-in outbursts in short orbital-period, low
mass-transfer-rate systems requires the disc to be much smaller than the
tidal-truncation radius. In this case the recurrence time of both inside-out
and outside-in outbursts have a similar dependence on the mass-transfer rate.

</DOC>
<DOC>
<DOCNO> 12556 </DOCNO>
Generalized conductance sum rule in atomic break junctions


  When an atomic-size break junction is mechanically stretched, the total
conductance of the contact remains approximately constant over a wide range of
elongations, although at the same time the transmissions of the individual
channels (valence orbitals of the junction atom) undergo strong variations. We
propose a microscopic explanation of this phenomenon, based on Coulomb
correlation effects between electrons in valence orbitals of the junction atom.
The resulting approximate conductance quantization is closely related to the
Friedel sum rule.

</DOC>
<DOC>
<DOCNO> 69410 </DOCNO>
Higgs and SUSY searches at future colliders


  In this talk, I discuss some aspects of Higgs searches at future colliders,
particularly comparing and contrasting the capabilities of LHC and Next Linear
Collider (NLC), including the aspects of Higgs searches in supersymmetric
theories. After this, I will discuss how the search and study of sparticles
other than the Higgs can give information about the parameters of the Minimal
Supersymmetric Standard Model (MSSM).

</DOC>
<DOC>
<DOCNO> 101419 </DOCNO>
Manifolds of Positive Scalar Curvature and Conformal Cobordism Theory


  We study here compact manifolds with positive scalar curvature metrics. We
use the relative Yamabe invariant from math.DG/0008138 to define the conformal
cobordism relation on the category of such manifolds. We prove that
corresponding conformal cobordism groups $\Pos_n^{\conf}(\gamma)$ are
isomorphic to the cobordism groups $\Pos_n(\gamma)$ defined topologically by S.
Stolz. As a corollary we show that the conformal concordance of positive scalar
curvature metrics coincides with the standard concordance relation. Our main
technical tools came from the analysis and conformal geometry.

</DOC>
<DOC>
<DOCNO> 100221 </DOCNO>
Pseudo-Riemannian metrics with parallel spinor fields and vanishing


  I discuss geometry and normal forms for pseudo-Riemannian metrics with
parallel spinor fields in some interesting dimensions. I also discuss the
interaction of these conditions for parallel spinor fields with the condition
that the Ricci tensor vanish (which, for pseudo-Riemannian manifolds, is not an
automatic consequence of the existence of a nontrivial parallel spinor field).

</DOC>
<DOC>
<DOCNO> 119445 </DOCNO>
Oscillating structure of \gamma-bursts and their possible origin


  As it is well-known that the hydrodinamic collapse of the massive star iron
core should lead to the production of a hot neutron star. The assumption is
made that the thermonuclear burning of the envelope matter, accreting onto the
hot neutron star, can proceed in the oscillatoric regime (analogously to that
happens during heat explosion of the carbon-oxigene cores of stars with smaller
masses). Local density oscillations in the vicinity of the neutron star surface
can generate shock waves, in which the stratification of the electron-positron
plasma from the rest of the matter can happen due to the light preasure. In the
case of the spherically symmetric collapse of the compact star it can lead to
the production of the expanding relativistic fireball shells with
characteristic oscillation time of ~ 10^{-2} s, observed in the cosmological
\gamma-bursts (GRB), can occur. It is pointed out that nonrotating massive
Wolf-Rayet's (WR) stars could be the source for the GRB, whose collapses,
according to a number of observations, can happen without any noticeable
ejection of the envelope.

</DOC>
<DOC>
<DOCNO> 13933 </DOCNO>
Novel Fine-Structure in the Low-Energy Excitation Spectrum of a High-Tc


  Angle-resolved photoemission spectroscopy is performed on single crystals of
the single-layer high-Tc superconductor Bi(2)Sr(2-x)La(x)CuO(6+d) at optimal
doping (x=0.4) in order to study in great detail the Zhang-Rice (ZR) singlet
band at the Fermi level. Besides the high crystal quality the advantages of a
single-layer material are the absence of bilayer effects and the distinct
reduction of thermal broadening. Due to the high energy and angle resolution
and, most important, due to the controlled variation of the polarization vector
of the synchrotron radiation the emission from the ZR singlet band reveals a
distinct fine-structure. It consists of two maxima, the first showing only weak
and the second at EF extremely strong polarization dependence. However, our
observation has enormous consequences for line shape analyses and the
determination of pseudo gaps by photoemission.

</DOC>
<DOC>
<DOCNO> 68320 </DOCNO>
Sigma-term physics


  We consider sigma-terms in $\pi\pi$, $\pi N$ and $K N$ scattering. While the
state of the art in $\pi\pi$ is in principle crystal clear, the kaon-nucleon
case is largely unexplored. The pion-nucleon system is in-between. We propose a
list of topics to be investigated in kaon-nucleon scattering, in order to make
optimal use of the precision data expected from DEAR.

</DOC>
<DOC>
<DOCNO> 12524 </DOCNO>
Solitons in one-dimensional interacting Bose-Einstein system


  A modified Gross-Pitaevskii approximation was introduced recently for bosons
in dimension $d\le2$ by Kolomeisky {\it et al.} (Phys. Rev. Lett. {\bf 85} 1146
(2000)). We use the density functional approach with sixth-degree interaction
energy term in the Bose field to reproduce the stationary-frame results of
Kolomeisky {\it et al.} for a one-dimensional Bose-Einstein system with a
repulsive interaction. We also find a soliton solution for an attractive
interaction, which may be boosted to a finite velocity by a Galilean
transformation. The stability of such a soliton is discussed analytically. We
provide a general treatment of stationary solutions in one dimension which
includes the above solutions as special cases. This treatment leads to a
variety of stationary wave solutions for both attractive and repulsive
interactions.

</DOC>
<DOC>
<DOCNO> 69193 </DOCNO>
Quartic mass corrections to R_had at order \alpha_s^3


  The total cross section for the production of massive quarks in electron
positron annihilation can be predicted in perturbative QCD. After expansion in
m^2/s the quartic terms, i.e. those proportional to m^4/s^2, are calculated up
to order \alpha_s^3 for vector and axial current induced rates. Predictions
relevant for charm, bottom and top quarks production are presented. The
\alpha_s^3 corrections are shown to be comparable to terms of order \alpha_s
and \alpha_s^2. As a consequence, the predictions exhibit a sizeable dependence
on the renormalization scale. The stability of the prediction is improved and,
at the same time, the relative size of the large order terms decreases by
replacing the running mass \bar{m}(\mu) with the scheme independent invariant
one \hat{m}. By combining these results with the prediction for massless case
and the quadratic mass terms the cross section for massive quark production at
electron positron colliders is put under control in order \alpha_s^3 from the
high energy region down to fairly low energies.

</DOC>
<DOC>
<DOCNO> 99831 </DOCNO>
Algebraic structures on quasi-primary states in superconformal algebras


  The algebraic structure on the subspace of the quasi-primary vectors given by
the projection of the (n) products of a conformal superalgebra is formulated.
As an application the complete list of simple physical conformal superalgebras
is given. The list contains a one-parameter family of superconformal algebras
with 4 supercharges that is simple for general values.

</DOC>
<DOC>
<DOCNO> 9884 </DOCNO>
Parametric Quantum Resonances for Bose-Einstein Condensates


  We generalize recent work on parametric resonances for nonlinear
Schr{\"o}dinger (NLS) type equations to the case of three dimensional
Bose-Einstein condensates at zero temperatures. We show the possibility of such
resonances in the three-dimensional case, using a moment method and numerical
simulations.

</DOC>
<DOC>
<DOCNO> 178616 </DOCNO>
Photoproduction of Pseudoscalar Mesons from Nuclei


  The subject of this doctoral study is the pseudoscalar meson photoproduction
from nuclei. Two types of processes are investigated in this regard: coherent
and quasifree processes. In the case of the coherent process, we study it for
the photoproduction of pion and eta mesons. We place special emphasis on the
various sources that put into question earlier
nonrelativistic-impulse-approximation calculations. These include: final-state
interactions, relativistic effects, off-shell ambiguities, and violations to
the impulse approximation. By far the largest uncertainty emerges from the
ambiguity in extending the many on-shell-equivalent representations of the
elementary amplitude off the mass shell. In the case of the quasifree process,
we study it for the photoproduction of the kaon meson. We compute the recoil
polarization of the lambda-hyperon and the photon asymmetry as well as the
differential cross section. By introducing the notion of a ``bound-nucleon
propagator'' we exploit Feynman's trace techniques to develop closed-form,
analytic expressions for all photoproduction observables. Our results indicate
that polarization observables are sensitive only to the fundamental physics,
making them ideal tools for the study of modifications to the elementary
process in the nuclear medium.

</DOC>
<DOC>
<DOCNO> 169754 </DOCNO>
Maximally entangled mixed states in two qubits


  We propose novel mixed states in two qubits, ``maximally entangled mixed
states'', which have a property that the amount of entanglement of these states
cannot be increased further by applying any unitary operations. The property is
proven when the rank of the states is less than 4, and confirmed numerically in
the other general cases. The corresponding entanglement of formation specified
by its eigenvalues gives an upper bound of that for density matrices with same
eigenvalues.

</DOC>
<DOC>
<DOCNO> 40427 </DOCNO>
First Measurement of the Photon Structure Function F_2,c^gamma


  The first measurement of F_2,c^gamma is presented. At low x the measurement
indicates a non-zero hadron-like component to F_2,c^gamma.
 At large x the measurement constitutes a test of perturbative QCD at
next-to-leading order, with only m_c and alpha_s as free parameters, with a
precision of O(40%).

</DOC>
<DOC>
<DOCNO> 9285 </DOCNO>
Triplet Dispersion in CuGeO_3: Perturbative Analysis


  We reconsider the 2d model for CuGeO_3 introduced previously (Phys. Rev.
Lett. 79, 163 (1997)). Using a computer aided perturbation method based on flow
equations we expand the 1-triplet dispersion up to 10th order. The expansion is
provided as a polynom in the model parameters. The latter are fixed by fitting
the theoretical result to experimental data obtained by INS. For a dimerization
delta = 0.08(1) we find an excellent agreement with experiment. This value is
at least 2 to 3 times higher than values deduced previously from 1d chain
approaches. For the intrachain frustration alpha_0 we find a smaller value of
0.25(3). The existence of interchain frustration conjectured previously is
confirmed by the analysis of temperature dependent susceptibility.

</DOC>
<DOC>
<DOCNO> 119123 </DOCNO>
Radiation-Hydrodynamical Collapse of Pregalactic Clouds in the


  To elucidate the effects of the UV background radiation on the collapse of
pregalactic clouds, we implement a radiation-hydrodynamical calculation,
combining one-dimensional spherical hydrodynamics with an accurate treatment of
the radiative transfer of ionizing photons. Both absorption and scattering of
UV photons are explicitly taken into account. It turns out that a gas cloud
contracting within the dark matter potential does not settle into hydrostatic
equilibrium, but undergoes run-away collapse even under the presence of the
external UV field. The cloud center is shown to become self-shielded against
ionizing photons by radiative transfer effects before shrinking to the rotation
barrier. Based on our simulation results, we further discuss the possibility of
H2 cooling and subsequent star formation in a run-away collapsing core. The
present results are closely relevant to the survival of subgalactic Population
III objects as well as to metal injection into intergalactic space.

</DOC>
<DOC>
<DOCNO> 10624 </DOCNO>
Collisional damping of the collective oscillations of a trapped Fermi


  We consider a Fermi gas confined by a harmonic trapping potential and we
highlight the role of the Fermi-Dirac statistics by studying frequency and
damping of collective oscillations of quadrupole type in the framework of the
quantum Boltzmann equation, in which statistical corrections are taken into
account in the collisional integral. We are able to describe the crossover from
the collisionless regime to the hydrodynamic one by introducing a
temperature-dependent relaxation time $\tau_Q$. We show that, in the degenerate
regime, the relaxation rate $1/\tau_Q$ exhibits a temperature dependence
different from the collision rate $\gamma$. We finally compare the collisional
properties of the Fermi gas with the ones of the Bose gas for temperatures
above the Bose-Einstein condensation.

</DOC>
<DOC>
<DOCNO> 9904 </DOCNO>
Mixed population Minority Game with generalized strategies


  We present a quantitative theory, based on crowd effects, for the market
volatility in a Minority Game played by a mixed population. Below a critical
concentration of generalized strategy players, we find that the volatility in
the crowded regime remains above the random coin-toss value regardless of the
"temperature" controlling strategy use. Our theory yields good agreement with
numerical simulations.

</DOC>
<DOC>
<DOCNO> 152034 </DOCNO>
On the Holographic RG-flow and the Low-energy, Strong Coupling, Large N


  From the AdS/CFT correspondence, we learn that the classical evolution of
supergravity in the bulk can be reduced to a RG-flow equation for the dual
low-energy, strongly coupled and large N gauge theory on the boundary. This
result has been used to obtain interesting relations between the various terms
in the gravitational part of the boundary effective action, in particular the
term that affect the cosmological constant. It is found that once the
cosmological constant is cancelled in the UV theory, the RG-flow symmetry of
the boundary effective action automatically implies the existence of zero
cosmological constant solutions that extend all the way into the IR. Given the
standard (and well founded) contradiction between the RG-flow idea and the
observational evidence of a small cosmological constant, this is considered to
be an important progress, albeit incomplete, towards the final solution.
Motivated by this success, it would be interesting to see whether this
RG-stability extends outside the scope of strong 't Hooft coupling and large N
regime that are implicitly assumed in the de Boer-Verlinde-Verlinde
Hamilton-Jacobi formulation of the holographic RG-flow equations of the
boundary theory. In this paper, we address this question. Taking into account
the leading order corrections in the 1/N and $\alpha'/{R^2}$ parameters, we
derive new bulk/boundary relations, from which one can read all the local terms
in the boundary effective action. Next, we use the resulting constraints, to
examine whether the RG-stability of the cosmological constant extends to the
new coupling regime. It would be also interesting to use these constraints to
study the Randall-Sundrum scenario in this case.

</DOC>
<DOC>
<DOCNO> 118364 </DOCNO>
The Globular Cluster Systems in the Coma Ellipticals. III: The Unique


  Using archival \hst WFPC2 data, we derive the metallicity distribution,
luminosity function, and spatial structure of the globular cluster system
around IC 4051, a giant E galaxy on the outskirts of the Coma cluster core. The
metallicity distribution derived from the (V-I) colors has a mean [Fe/H] =
-0.3, a near-complete lack of metal-poor clusters, and only a small metallicity
gradient with radius; it may, however, have two roughly equal metallicity
subcomponents, centered at [Fe/H] ~ 0.0 and -1.0. The luminosity distribution
(GCLF) has the Gaussian-like form observed in all other giant E galaxies, with
a peak (turnover) at V = 27.8, consistent with a Coma distance of 100 Mpc. The
radial profiles of both the GCS and the halo light show an unusually steep
falloff which may indicate that the halo of this galaxy has been tidally
truncated. Lastly, the specific frequency of the GCS is remarkably large: we
find S_N = 11 +- 2, resembling the central cD-type galaxies even though IC 4051
is not a cD or brightest cluster elliptical. A formation model consistent with
most of the observations would be that this galaxy was subjected to removal of
a large fraction of its protogalactic gas shortly after its main phase of
globular cluster formation, probably by its first passage through the Coma
core. Since then, no significant additions due to accretions or mergers have
taken place.

</DOC>
<DOC>
<DOCNO> 70121 </DOCNO>
Examination of direct-photon and pion production in proton-nucleon


  We present a study of inclusive direct-photon and pion production in hadronic
interactions, focusing on a comparison of the ratio of gamma/pi0 yields with
expectations from next-to-leading order perturbative QCD (NLO pQCD). We also
examine the impact of a phenomenological model involving k_T smearing (which
approximates effects of additional soft-gluon emission) on absolute predictions
for photon and pion production and their ratio.

</DOC>
<DOC>
<DOCNO> 102291 </DOCNO>
Isospectral pairs of metrics on balls, spheres, and other manifolds with


  The first isospectral pairs of metrics are constructed on balls and spheres.
This long standing problem, concerning the existence of such pairs, has been
solved by a new method called "Anticommutator Technique." Among the wide range
of such pairs, the most striking examples are provided on (4k-1)-dimensional
spheres, where k > 2. One of these metrics is homogeneous (since it is the
metric on the geodesic sphere of a 2-point homogeneous space), while the other
is locally inhomogeneous. These examples demonstrate the surprising fact that
no information about the isometries is encoded in the spectrum of Laplacian
acting on functions. In other words, "The group of isometries, even the local
homogeneity property, is lost to the "Non-Audible" in the debate of "Audible
versus Non-Audible Geometry"."

</DOC>
<DOC>
<DOCNO> 174567 </DOCNO>
Contemporary presence of dynamical and statistical production of


  The $^{58}Ni+^{58}Ni$ reaction at 30 MeV/nucleon has been experimentally
investigated at the Superconducting Cyclotron of the INFN Laboratori Nazionali
del Sud. In midperipheral collisions the production of massive fragments
(4$\le$Z$\le$12), consistent with the statistical fragmentation of the
projectile-like residue and the dynamical formation of a neck, joining
projectile-like and target-like residues, has been observed. The fragments
coming from these different processes differ both in charge distribution and
isotopic composition. In particular it is shown that these mechanisms leading
to fragment production act contemporarily inside the same event.

</DOC>
<DOC>
<DOCNO> 116342 </DOCNO>
Semiclassical description of multiphoton processes


  We analyze strong field atomic dynamics semiclassically, based on a full
time-dependent description with the Hermann-Kluk propagator. From the
properties of the exact classical trajectories, in particular the accumulation
of action in time, the prominent features of above threshold ionization (ATI)
and higher harmonic generation (HHG) are proven to be interference phenomena.
They are reproduced quantitatively in the semiclassical approximation.
Moreover, the behavior of the action of the classical trajectories supports the
so called strong field approximation which has been devised and postulated for
strong field dynamics.

</DOC>
<DOC>
<DOCNO> 68731 </DOCNO>
Status of the neutrino decay solution to the solar neutrino problem


  We re-examine the neutrino decay solution to the solar neutrino problem in
the light of the SuperKamiokande (SK) data. For the decay solution the SK
spectrum data by its own can provide a fit comparable to the fit obtained from
the MSW solution. However when one combines the results from the total rates of
the $^{37}{Cl}$ and $^{71}{Ga}$ experiments the fit becomes much poorer.

</DOC>
<DOC>
<DOCNO> 40661 </DOCNO>
Impact of bosonic decays on the search for t~_1 and b~_1 squarks


  We perform a detailed study of the decays of the lighter top and bottom
squarks (t~_1 and b~_1) in the Minimal Supersymmetric Standard Model (MSSM). We
show that the decays into Higgs or gauge bosons, i.e. t~_1 -> b~_1 + (H^+ or
W^+) and b~_1 -> t~_1 + (H^- or W^-), can be dominant in a wide range of the
MSSM parameters due to the large Yukawa couplings and mixings of t~ and b~.
Compared to the decays into fermions, such as t~_1 -> t + (neutralino_i or
gluino) and t~_1 -> b + chargino_j, these bosonic decay modes can have
significantly different decay distributions. We also show that the effect of
the supersymmetric QCD running of the quark and squark parameters on the t~_1
and b~_1 decay branching ratios is quite dramatic. These could have an
important impact on the search for t~_1 and b~_1 and the determination of the
MSSM parameters at future colliders.

</DOC>
<DOC>
<DOCNO> 72200 </DOCNO>
QCD-like Theories at Finite Baryon and Isospin Density


  We use 2-color QCD as a model to study the effects of simultaneous presence
of chemical potentials for isospin charge, $\mu_I$, and for baryon number,
$\mu_B$. We determine the phase diagrams for 2 and 4 flavor theories using the
method of effective chiral Lagrangians at low densities and weak coupling
perturbation theory at high densities. We determine the values of various
condensates and densities as well as the spectrum of excitations as functions
of $\mu_I$ and $\mu_B$. A similar analysis of QCD with quarks in the adjoint
representation is also presented. Our results can be of relevance for lattice
simulations of these theories. We predict a phase of inhomogeneous condensation
(Fulde-Ferrel-Larkin-Ovchinnikov phase) in the 2 colour 2 flavor theory, while
we do not expect it the 4 flavor case or in other realizations of QCD with a
positive measure.

</DOC>
<DOC>
<DOCNO> 102001 </DOCNO>
Analysis of a Disease Transmission Model with two Groups of Infectives


  In this paper, we give a complete analysis of an SIS epidemiological model in
a population of varying size with two dissimilar groups of infective
individuals. It is mainly based on the discussion of the existence and
stability of equilibria of the proportions system and the result is in terms of
a threshold parameter which governs the stability of the disease free
equilibrium.

</DOC>
<DOC>
<DOCNO> 10533 </DOCNO>
Temperature dependence of the interlayer magnetoresistance of


  The interlayer magnetoresistance of a quasi-one-dimensional Fermi liquid is
considered for the case of a magnetic field that is rotated within the plane
perpendicular to the most-conducting direction. Within semi-classical transport
theory dips in the magnetoresistance occur at integer amgic angles only when
the electronic dispersion parallel to the chains is nonlinear. If the field
direction is fixed at one of the magic angles and the temperature is varied the
resulting variation of the scattering rate can lead to a non-monotonic
variation of the interlayer magnetoresistance with temperature. Although the
model considered here gives a good description of some of the properties of the
Bechgaard salts, (TMTSF)2PF6 for pressures less than 8kbar and (TMTSF)2ClO4 it
gives a poor description of their properties when the field is parallel to the
layers and of the intralayer transport.

</DOC>
<DOC>
<DOCNO> 170366 </DOCNO>
Dynamics of quantum entanglement


  A model of discrete dynamics of entanglement of bipartite quantum state is
considered. It involves a global unitary dynamics of the system and periodic
actions of local bistochastic or decaying channel. For initially pure states
the decay of entanglement is accompanied with an increase of von Neumann
entropy of the system. We observe and discuss revivals of entanglement due to
unitary interaction of both subsystems. For some mixed states having different
marginal entropies of both subsystems (one of them larger than the global
entropy and the other one one smaller) we find an asymmetry in speed of
entanglement decay. The entanglement of these states decreases faster, if the
depolarizing channel acts on the "classical" subsystem, characterized by
smaller marginal entropy.

</DOC>
<DOC>
<DOCNO> 70567 </DOCNO>
CP violation in neutrino oscillations and L/E flatness of the e-like


  We show that if the presently observed L/E-flatness of the electron-like
event ratio in the Super-Kamiokande atmospheric neutrino data is confirmed then
the indicated ratio must be {\em unity}. Further, it is found that once CP is
violated the exact L/E flatness implies: (a) The CP-violating phase, in the
standard parameterization, is narrowed down to two possibilities pm pi/2, and
(b) The mixing between the second and the third generations must be maximal.
With these results at hand, we argue that a dedicated study of the L/E-flatness
of the electron-like event ratio by Super-Kamiokande can serve as an initial
investigatory probe of CP violation in the neutrino sector. The assumptions
under which these results hold are explicitly stated.

</DOC>
<DOC>
<DOCNO> 123271 </DOCNO>
Rossby Wave Instability of Thin Accretion Disks - III. Nonlinear


  (abridged) We study the nonlinear evolution of the Rossby wave instability in
thin disks using global 2D hydrodynamic simulations. The key questions we are
addressing in this paper are: (1) What happens when the instability becomes
nonlinear? Specifically, does it lead to vortex formation? (2) What is the
detailed behavior of a vortex? (3) Can the instability sustain itself and can
the vortex last a long time? Among various initial equilibria that we have
examined, we generally find that there are three stages of the disk evolution:
(1) The exponential growth of the initial small amplitude perturbations. This
is in excellent agreement with the linear theory; (2) The production of large
scale vortices and their interactions with the background flow, including
shocks. Significant accretion is observed due to these vortices. (3) The
coupling of Rossby waves/vortices with global spiral waves, which facilitates
further accretion throughout the whole disk. Even after more than 20
revolutions at the radius of vortices, we find that the disk maintains a state
that is populated with vortices, shocks, spiral waves/shocks, all of which
transport angular momentum outwards. We elucidate the physics at each stage and
show that there is an efficient outward angular momentum transport in stages
(2) and (3) over most parts of the disk, with an $\alpha$ in the range from
$10^{-4}$ to $10^{-2}$. We show why such vortices prove to be almost ideal
``units'' in transporting angular momentum outwards, namely by positively
correlating the radial and azimuthal velocity components. We find some special
cases in which entropy can remain the same while angular momentum is
transported. We conclude that Rossby wave/vortex instability is an efficient,
purely hydrodynamic mechanism for angular momentum transport in thin disks.

</DOC>
<DOC>
<DOCNO> 11042 </DOCNO>
Extended Kinetic Models with Waiting-Time Distributions: Exact Results


  Inspired by the need for effective stochastic models to describe the complex
behavior of biological motor proteins that move on linear tracks exact results
are derived for the velocity and dispersion of simple linear sequential models
(or one-dimensional random walks) with general waiting-time distributions. The
concept of ``mechanicity'' is introduced in order to conveniently quantify
departures from simple ``chemical,'' kinetic rate processes, and its
significance is briefly indicated. The results are extended to more elaborate
models that have finite side-branches and include death processes (to represent
the detachment of a motor from the track).

</DOC>
<DOC>
<DOCNO> 119698 </DOCNO>
High-Redshift Galaxies in Cold Dark Matter Models


  We use hydrodynamic cosmological simulations to predict the star formation
properties of high-redshift galaxies (z=2-6) in five variants of the
inflationary cold dark matter scenario, paying particular attention to z=3, the
redshift of the largest "Lyman-break galaxy" (LBG) samples. Because we link the
star formation timescale to the local gas density, the rate at which a galaxy
forms stars is governed mainly by the rate at which it accretes cooled gas from
the surrounding medium. At z=3, star formation in most of the simulated
galaxies is steady on 200 Myr timescales, and the instantaneous star formation
rate (SFR) is correlated with total stellar mass. However, there is enough
scatter in this correlation that a sample selected above a given SFR threshold
may contain galaxies with a fairly wide range of masses. The redshift history
and global density of star formation in the simulations depend mainly on the
amplitude of mass fluctuations in the underlying cosmological model. The three
models whose mass fluctuation amplitudes agree with recent analyses of the
Lyman-alpha forest also reproduce the observed luminosity function of LBGs
reasonably well, though the dynamic range of the comparison is small and the
theoretical and observational uncertainties are large. The models with higher
and lower amplitudes appear to predict too much and too little star formation,
respectively, though they are not clearly ruled out. The intermediate amplitude
models predict SFR ~ 30-40 Msun/yr for galaxies with a surface density 1 per
arcmin^2 per unit redshift at z=3. They predict much higher surface densities
at lower SFR, and significant numbers of galaxies with SFR > 10 Msun/yr at z >=
5.

</DOC>
<DOC>
<DOCNO> 150753 </DOCNO>
Quantization of Point-Like Particles and Consistent Relativistic Quantum


  We revise the problem of the quantization of relativistic particle models
(spinless and spinning), presenting a modified consistent canonical scheme. One
of the main point of the modification is related to a principally new
realization of the Hilbert space. It allows one not only to include arbitrary
backgrounds in the consideration but to get in course of the quantization a
consistent relativistic quantum mechanics, which reproduces literally the
behavior of the one-particle sector of the corresponding quantum field. In
particular, in a physical sector of the Hilbert space a complete positive
spectrum of energies of relativistic particles and antiparticles is reproduced,
and all state vectors have only positive norms.

</DOC>
<DOC>
<DOCNO> 151589 </DOCNO>
Domain Walls with Localised Gravity and Domain-Wall/QFT Correspondence


  We review general domain-wall solutions supported by a delta-function source,
together with a single pure exponential scalar potential in supergravity. These
scalar potentials arise from a sphere reduction in M-theory or string theory.
There are several examples of flat (BPS) domain walls that lead to a
localisation of gravity on the brane, and for these we obtain the form of the
corrections to Newtonian gravity. These solutions are lifted back on certain
internal spheres to D=11 and D=10 as M-branes and D-branes. We find that the
domain walls that can trap gravity yield M-branes or Dp-branes that have a
natural decoupling limit, i.e. p\le 5, with the delta-function source providing
an ultra-violet cut-off in a dual quantum field theory. This suggests that the
localisation of gravity can generally be realised within a Domain-wall/QFT
correspondence, with the delta-function domain-wall source providing a cut-off
from the space-time boundary for these domain-wall solutions. We also discuss
the form of the one-loop corrections to the graviton propagator from the
boundary QFT that would reproduce the corrections to the Newtonian gravity on
the domain wall.

</DOC>
<DOC>
<DOCNO> 101835 </DOCNO>
Generators for the cohomology ring of Hilbert schemes of points on


  Using the methods developed in [LQW], math.AG/0009132, we obtain a second set
of generators for the cohomology ring of the Hilbert scheme of points on an
arbitrary smooth projective surface over the field of complex numbers. These
generators have clear and simple geometric as well as algebraic descriptions.

</DOC>
<DOC>
<DOCNO> 119132 </DOCNO>
Analytic Time Delays and H_0 Estimates for Gravitational Lenses


  We study gravitational lens time delays for a general family of lensing
potentials, which includes the popular singular isothermal elliptical potential
and singular isothermal elliptical density distribution but allows general
angular structure. Using a novel approach, we show that the time delay can be
cast in a very simple form, depending only on the observed image positions.
Including an external shear changes the time delay proportional to the shear
strength, and varying the radial profile of the potential changes the time
delay approximately linearly. These analytic results can be used to obtain
simple estimates of the time delay and the Hubble constant in observed
gravitational lenses. The naive estimates for four of five time delay lenses
show surprising agreement with each other and with local measurements of H_0;
the complicated Q 0957+561 system is the only outlier. The agreement suggests
that it is reasonable to use simple isothermal lens models to infer H_0,
although it is still important to check this conclusion by examining detailed
models and by measuring more lensing time delays.

</DOC>
<DOC>
<DOCNO> 9451 </DOCNO>
Coexisting Kondo singlet state with antiferromagnetic long-range order:


  The ground-state phase diagram of a half-filled anisotropic Kondo lattice
model is calculated within a mean-field theory. For small transverse exchange
coupling $J_{\perp}<J_{\perp c1}$, the ground state shows an antiferromagnetic
long-range order with finite staggered magnetizations of both localized spins
and conduction electrons. When $J_{\perp}>J_{\perp c2}$, the long-range order
is destroyed and the system is in a disordered Kondo singlet state with a
hybridization gap. Both ground states can describe the low-temperature phases
of Kondo insulating compounds. Between these two distinct phases, there may be
a coexistent regime as a result of the balance between local Kondo screening
and magnetic interactions.

</DOC>
<DOC>
<DOCNO> 100354 </DOCNO>
Polarized distances between quantum states and observables


  The proposition 1 is incomplete. In some of the examples D(a,b) may not obey
the triangle inequality. The paper is withdrawn for further elaboration.

</DOC>
<DOC>
<DOCNO> 80592 </DOCNO>
Anisotropic Improved Actions


  The studies of the quantum corrections for the anisotropy
parameter,$\eta(=\xi_R/\xi_B)$, for the improved actions, $\beta (C_0
L({Plaq.}) + C_1 L({Rect.}))$, are proceeded in the medium to strong coupling
region on anisotropic lattices. The global features for the $\eta$ parameters
as a function of $\beta$ and the coefficient $C_{1}$ have been clarified. It
has been found by the perturbative analysis that as $C_1$ decreases, the slope
of the $\eta(\beta)$ becomes less steep and for the actions whose $C_{1}$ is
less than -0.160, $\eta$ decreases as $\beta$ decreases, contrary to the case
of the standard action. In the medium to strong coupling region, the $\eta$
parameter begins to increase as $\beta$ decreases for all $C_{1}$. This means
that for the actions with $C_{1} < -0.160$, the one-loop perturbative results
for $\eta$ break down qualitatively and the $\eta$ parameters have a dip. As a
result of this dip structure the $\eta$ for Iwasaki's action remains close to
unity in the wide range of $\beta$.

</DOC>
<DOC>
<DOCNO> 117384 </DOCNO>
On the Interpretation of the Optical Spectra of L-type Dwarfs


  We present synthetic optical spectra in the range 640-930 nm of a sample of
field L dwarfs and the brown dwarf GL229B. Our computations show that Li, Na,
K, Rb, and Cs govern the spectra of these objects, with Na and K contributing
significantly to block the optical emergent radiation. Molecular absorptions of
TiO, VO, CrH, FeH and CaH also dominate in the early L-types showing a strength
that progressively decreases for later types. We find that the densities of
these molecules in the atmospheres are considerably smaller by larger factors
than those predicted by the chemical equilibrium. In order to reproduce the
overall shape of the optical spectra an additional opacity (AdO) is required to
be implemented in the computations. We have modelled it with a simple law [a0
(nu / nu0)^N, N=4], and found that this provides a good fit to the data. This
AdO could be due to molecular/dust absorption or to dust scattering. The EWs
and intensities of the alkali lines are highly affected by this opacity. The Li
line at 670.8 nm, widely used as a substellarity discriminator, is more
affected by the AdO than by the natural depletion of neutral Li. Our
computations display a rather strong feature even at Teffs around 1000 K;
depending on the Teff and on the amount of dust in the atmospheres of very cool
dwarfs, it might be possible to detect Li even at temperatures this cool.
Changes in the physical conditions of dust formation in L-type dwarfs will
cause variability of the alkali lines.

</DOC>
<DOC>
<DOCNO> 71826 </DOCNO>
Feynman-Schwinger technique in field theories


  In these lectures we introduce the Feynman-Schwinger representation method
for solving nonperturbative problems in field theory. As an introduction we
first give a brief overview of integral equations and path integral methods for
solving nonperturbative problems. Then we discuss the Feynman-Schwinger (FSR)
representation method with applications to scalar interactions. The FSR
approach is a continuum path integral integral approach in terms of covariant
trajectories of particles. Using the exact results provided by the FSR approach
we test the reliability of commonly used approximations for nonperturbative
summation of interactions for few body systems.

</DOC>
<DOC>
<DOCNO> 7849 </DOCNO>
On the geometric origin of mechanical properties of granular materials


  Some remarkable generic properties, related to isostaticity and potential
energy minimization, of equilibrium configurations of assemblies of rigid,
frictionless grains are studied. Isostaticity -the uniqueness of the forces,
once the list of contacts is known- is established in a quite general context,
and the important distinction between isostatic problems under given external
loads and isostatic (rigid) structures is presented. Complete rigidity is only
guaranteed, on stability grounds, in the case of spherical cohesionless grains.
Otherwise, the network of contacts might deform elastically in response to load
increments, even though grains are rigid. This sets an uuper bound on the
contact coordination number. The approximation of small displacements (ASD)
allows to draw analogies with other model systems studied in statistical
mechanics, such as minimum paths on a lattice. It also entails the uniqueness
of the equilibrium state (the list of contacts itself is geometrically
determined) for cohesionless grains, and thus the absence of plastic
dissipation. Plasticity and hysteresis are due to the lack of such uniqueness
and may stem, apart from intergranular friction, from small, but finite,
rearrangements, in which the system jumps between two distinct potential energy
minima, or from bounded tensile contact forces. The response to load increments
is discussed. On the basis of past numerical studies, we argue that, if the ASD
is valid, the macroscopic displacement field is the solution to an elliptic
boundary value problem (akin to the Stokes problem).

</DOC>
<DOC>
<DOCNO> 150331 </DOCNO>
Radiative Contributions to the Effective Action of Self-Interacting


  The effect of quantum corrections to a conformally invariant field theory for
a self-interacting scalar field on a curved manifold with boundary is
considered. The analysis is most easily performed in a space of constant
curvature the boundary of which is characterised by constant extrinsic
curvature. An extension of the spherical formulation in the presence of a
boundary is attained through use of the method of images. Contrary to the
consolidated vanishing effect in maximally symmetric space-times the
contribution of the massless "tadpole" diagram no longer vanishes in
dimensional regularisation. As a result, conformal invariance is broken due to
boundary-related vacuum contributions. The evaluation of one-loop contributions
to the two-point function suggests an extension, in the presence of matter
couplings, of the simultaneous volume and boundary renormalisation in the
effective action.

</DOC>
<DOC>
<DOCNO> 119427 </DOCNO>
Search for clusters at high redshift - I. Candidate Lya emitters near


  Radio, optical and X-ray observations of the powerful radio galaxy PKS
1138-262 at z=2.156 have suggested that this galaxy is a massive galaxy in the
center of a forming cluster. We have imaged 1138-262 and the surrounding 38
square arcminute field with the Very Large Telescope in a broad band and a
narrow band encompassing the redshifted Lya emission. We detect 50 objects with
rest equivalent width larger than 20 A and a luminous, highly extended Lya halo
around 1138-262. If the radio galaxy is at the center of a forming cluster,
these objects are candidate Lya emitting cluster galaxies.

</DOC>
<DOC>
<DOCNO> 84298 </DOCNO>
Birth of the Universe as anti-tunnelling from the string perturbative


  The decay of the string perturbative vacuum, if triggered by a suitable,
duality-breaking dilaton potential, can efficiently proceed via the parametric
amplification of the Wheeler-De Witt wave function in superspace, and can
appropriately describe the birth of our Universe as a quantum process of pair
production from the vacuum.

</DOC>
<DOC>
<DOCNO> 71693 </DOCNO>
Chiral perturbation theory and the 1/N_c-expansion


  We briefly review the effective theory that describes the low energy
properties of QCD with three light quarks and a large number of colours, N_c,
and then discuss the mechanisms that forbid the Kaplan-Manohar transformation
in this framework.

</DOC>
<DOC>
<DOCNO> 170621 </DOCNO>
Generalization of the entanglement of formation for multi-party systems


  We present the generalization of the entanglement of formation for
three-party systems in a pure state. For three qubit system we derive out its
explicit and closed expression which is a linear combination of the binary
entropy functions with various arguments, and these arguments are clearly
determined in terms of the components of state vector of three qubits. As a
reasonable measure of entanglement, the main behaviors and elementary
properties of this generalized entanglement of formation are showed through
discussing some important and interesting examples. Moreover, we propose how to
extend our definition to a mixed state in according to the familiar idea. Then,
we suggest the generalization of the entanglement of formation for multi-party
systems which is consistent with the regular definition for two-party systems
and our definition for three-party systems.

</DOC>
<DOC>
<DOCNO> 119929 </DOCNO>
HST-STIS Observations of the Cygnus Loop: Spatial Structure of a


  We present a spatially-resolved ultraviolet spectrum of a non-radiative shock
front in the Cygnus Loop, obtained with the Space Telescope Imaging
Spectrograph (STIS) on board the Hubble Space Telescope (HST). The spectrum
covers the wavelength range 1118 - 1716 angstroms, with an effective spectral
resolution of ~12 angstroms. The 0.1" spatial resolution of these data provides
a huge improvement over earlier ultraviolet spectra, allowing us to study the
spatial distribution of high ionization line emission directly behind the shock
front. We are able to isolate individual shock features in our spectrum by
comparing the STIS spectrum with a WFPC2 H-alpha image of the region. Isolating
the brightest shock tangency, we identify lines of NV, CIV, HeII, OV, OIV] and
SiIV, and NIV] as well as the hydrogen 2-photon continuum. The NV line peaks
about 0.3" behind the CIV and HeII emission and is spatially broader. Also, the
observed line ratios of CIV and HeII to NV are higher in our bright shock
spectrum than in previous observations of the same filament obtained through
much larger apertures, indicating that there must be a more widely distributed
component of the NV emission. We calculate shock models and show that the
observed separation between the CIV and NV emission zones and observed line
intensities constrain the combinations of shock velocity and pre-shock density
that are allowed.

</DOC>
<DOC>
<DOCNO> 151142 </DOCNO>
Abrikosov String in N=2 Supersymmetric QED


  We study the Abrikosov-Nielsen-Olesen string in N=2 supersymmetric QED with
N=2-preserving superpotential, in which case the Abrikosov string is found to
be 1/2-BPS saturated. Adding a quadratic small perturbation in the
superpotential breaks N=2 supersymmetry to N=1 supersymmetry. Then the
Abrikosov string is no longer BPS saturated. The difference between the string
tensions for the non-BPS and BPS saturated situation is found to be negative to
the first order of the perturbation parameter.

</DOC>
<DOC>
<DOCNO> 13027 </DOCNO>
Static Spin Correlation in LTT Phase of


  We have carried out elastic neutron scattering measurements on
La$_{1.875}$Ba$_{0.075}$Sr$_{0.05}$CuO$_4$ single crystal ($T_c\approx$10K).
Incommensurate elastic magnetic peaks were observed in the low-tamperature
tetragonal phase with the propergation vector parallel/perpendicular to
in-plane Cu-O bond direction. The magnetic peak intensity normalized by the
sample volume is approximately six times larger than that of the orthorhombic
La$_{1.88}$Sr$_{0.12}$CuO$_4$ at low temperature.

</DOC>
<DOC>
<DOCNO> 120139 </DOCNO>
Gas flow in barred galaxies


  I briefly review the properties of the gas flow in and around the region of
the bar in a disc galaxy and discuss the corresponding inflow and the loci of
star formation. I then review the flow of gas in barred galaxies which have an
additional secondary bar. Finally I discuss the signatures of bars in edge-on
galaxies.

</DOC>
<DOC>
<DOCNO> 170723 </DOCNO>
Preparation of pseudo-pure states by line-selective pulses in Nuclear


  A new method of preparing the pseudo-pure state of a spin system for quantum
computation in liquid nuclear magnetic resonance (NMR) was put forward and
demonstrated experimentally. Applying appropriately connected line-selective
pulses simultaneously and a field gradient pulse techniques we acquired
straightforwardly all pseudo-pure states for two qubits in a single experiment
much efficiently. The signal intensity with the pseudo-pure state prepared in
this way is the same as that of temporal averaging. Our method is suitable for
the system with arbitrary numbers of qubits. As an example of application, a
highly structured search algorithm----Hogg's algorithm was also performed on
the pseudo-pure state $\mid 00>$ prepared by our method.

</DOC>
<DOC>
<DOCNO> 117516 </DOCNO>
Current Development of the Photo-Ionization Code Cloudy


  This paper describes the most important differences between Cloudy 90 and
Cloudy 94, the most recent upgrade of the code which has now been posted on the
WWW. It also describes the upgrade of the grain model in Cloudy which is
currently underway.

</DOC>
<DOC>
<DOCNO> 118819 </DOCNO>
The Intrinsic Shape Distribution of a Sample of Elliptical Galaxies


  We apply the dynamical modeling approach of Statler (1994b) to 13 elliptical
galaxies from the Davies and Birkinshaw (1988) sample of radio galaxies to
derive constraints on their intrinsic shapes and orientations. We develop an
iterative Bayesian algorithm to combine these results to estimate the parent
shape distribution from which the sample was drawn, under the assumption that
this parent distribution has no preferred orientation. In the process we obtain
improved estimates for the shapes of individual objects. The parent shape
distribution shows a tendency toward bimodality, with peaks at the oblate and
prolate limits. Under minimal assumptions about the galaxies' internal
dynamics, 35% of the objects would be strongly triaxial (0.2 < T < 0.8).
However, the parent distribution is sensitive to the assumed orbit populations
in the galaxies. Dynamical configurations in which all galaxies rotate purely
about either their long or short axes can be ruled out because they would
require the sample to have a strong orientation bias. Configurations in which
the mean motion about the short or long axis is either ``disklike''---dropping
off away from the symmetry planes---or ``spheroidlike''---remaining roughly
constant at a given radius---are equally viable. Spheroidlike rotation in the
long-axis or short-axis tube orbits significantly lowers the abundance of
prolate or oblate galaxies, respectively. If rotation in ellipticals is
generally disklike, then triaxiality is rare; if spheroidlike, triaxiality is
common.

</DOC>
<DOC>
<DOCNO> 151043 </DOCNO>
Consistency of the Born Approximation for the spin-1/2 Aharonov-Bohm


  The relativistic scattering of a spin-1/2 particle from an infinitely long
solenoid is considered in the framework of covariant perturbation theory. The
first order term agrees with the corresponding term in the series expansion of
the exact amplitude, and second order term vanishes, thus proving that Born
approximation is consistent.

</DOC>
<DOC>
<DOCNO> 152279 </DOCNO>
A note on regular type 0 solutions and confining gauge theories


  We discuss some features of the regular supergravity solution for fractional
branes on a deformed conifold, recently found by Klebanov-Strassler, mostly
adapting it to a type 0 non-sypersymmetric context. The non-supersymmetric
gauge theory is SU(M)*SU(M) with two bi-fundamental Weyl fermions. The tachyon
is now stabilized by the RR antisymmetric tensor flux. We briefly discuss the
most general non-supersymmetric theory on electric, magnetic and fractional
type 0 D3-branes on a conifold. This includes the pure SU(N) theory.

</DOC>
<DOC>
<DOCNO> 8799 </DOCNO>
Stability of the Smectic Quantum Hall State: A Quantitative Study


  We present an effective elastic theory which {\em quantitatively} describes
the stripe phase of the two-dimensional electron gas in high Landau levels
($N\geq2$). The dynamical matrix is obtained with remarkably high precision
from the density-density correlation function in the time-dependent
Hartree-Fock approximation. A renormalization group analysis shows that at T=0,
as the partial filling factor $\Delta\nu\equiv\nu-\lfloor\nu\rfloor$ moves away
from 1/2, the anisotropic conducting state may undergo quantum phase
transitions: stripes may get pinned along their conducting direction by
disorder, or may lock into one another to form a two-dimensional crystal. The
model predicts values of $\Delta\nu$ for each transition. The transitions
should be reflected in the temperature dependence of the dissipative
conductivity.

</DOC>
<DOC>
<DOCNO> 13582 </DOCNO>
Development of a tight-binding potential for bcc-Zr. Application to the


  We present a tight-binding potential based on the moment expansion of the
density of states, which includes up to the fifth moment. The potential is
fitted to bcc and hcp Zr and it is applied to the computation of vibrational
properties of bcc-Zr. In particular, we compute the isothermal elastic
constants in the temperature range 1200K < T < 2000K by means of standard Monte
Carlo simulation techniques. The agreement with experimental results is
satisfactory, especially in the case of the stability of the lattice with
respect to the shear associated with C'. However, the temperature decrease of
the Cauchy pressure is not reproduced. The T=0K phonon frequencies of bcc-Zr
are also computed. The potential predicts several instabilities of the bcc
structure, and a crossing of the longitudinal and transverse modes in the (001)
direction. This is in agreement with recent ab initio calculations in Sc, Ti,
Hf, and La.

</DOC>
<DOC>
<DOCNO> 40362 </DOCNO>
Searches for neutral Higgs bosons in e+e- collisions at centre-of-mass


  Searches for neutral Higgs bosons are performed with the 237 pb-1 of data
collected in 1999 by the ALEPH detector at LEP, for centre-of-mass energies
between 191.6 and 201.6 GeV. These searches apply to Higgs bosons within the
context of the Standard Model and its minimal supersymmetric extension (MSSM)
as well as to invisibly decaying Higgs bosons. No evidence of a signal is seen.
A lower limit on the mass of the Standard Model Higgs boson of 107.7 GeV/c2 at
95% confidence level is set. In the MSSM, lower limits of 91.2 and 91.6 GeV/c2
are derived for the masses of the neutral Higgs bosons h and A, respectively.
For a Higgs boson decaying invisibly and produced with the Standard Model cross
section, masses below 106.4 GeV/c2 are excluded.

</DOC>
<DOC>
<DOCNO> 101826 </DOCNO>
Gluing theorems for complete anti-self-dual spaces


  We give new and rather general gluing theorems for anti-self-dual (ASD)
conformal structures, following the method suggested by Floer. The main result
is a gluing theorem for pairs of conformally ASD manifolds `joined' across a
common piece (union of connected components) of their boundaries. This theorem
genuinely operates in the b-category (in the sense of Melrose) and in general
the boundary of the joined manifold can be non-empty. The resulting metric is a
conformally ASD b-metric or, in more traditional language, a complete
conformally ASD metric with cylindrical asymptotics. We also study
hermitian-ASD conformal structures on complex surfaces in relation to
scalar-flat K\"ahler geometry. The general results are illustrated with a
simple application, showing that the blow-up of C^2 at an arbitrary finite set
of points admits scalar-flat K\"ahler metrics that are asymptotic to the
Euclidean metric at infinity. A number of vanishing theorems for the
obstruction space is also included.

</DOC>
<DOC>
<DOCNO> 7892 </DOCNO>
Anomalously large oxygen-ordering contribution to the thermal expansion


  We present high-resolution capacitance dilatometry studies from 5 - 500 K of
untwinned YBa2Cu3Ox (Y123) single crystals for x ~ 6.95 and x = 7.0. Large
contributions to the thermal expansivities due to O-ordering are found for x ~
6.95, which disappear below a kinetic glass-like transition near room
temperature. The kinetics at this glass transition is governed by an energy
barrier of 0.98 +- 0.07 eV, in very good agreement with other O-ordering
studies. Using thermodynamic arguments, we show that O-ordering in the Y123
system is particularly sensitive to uniaxial pressure (stress) along the chain
axis and that the lack of well-ordered chains in Nd123 and La123 is most likely
a consequence of a chemical-pressure effect.

</DOC>
<DOC>
<DOCNO> 170530 </DOCNO>
A Lorentz-invariant look at quantum clock synchronization protocols


  Recent work has raised the possibility that quantum information theory
techniques can be used to synchronize atomic clocks nonlocally. One of the
proposed algorithms for quantum clock synchronization (QCS) requires
distribution of entangled pure singlets to the synchronizing parties. Such
remote entanglement distribution normally creates a relative phase error in the
distributed singlet state which then needs to be purified asynchronously. We
present a fully relativistic analysis of the QCS protocol which shows that
asynchronous entanglement purification is not possible, and, therefore, that
the proposed QCS scheme remains incomplete. We discuss possible directions of
research in quantum information theory which may lead to a complete, working
QCS protocol.

</DOC>
<DOC>
<DOCNO> 117649 </DOCNO>
Non-parametric star formation histories for 5 dwarf spheroidal galaxies


  We use recent HST colour-magnitude diagrams of the resolved stellar
populations of a sample of local dSph galaxies (Carina, LeoI, LeoII, Ursa Minor
and Draco) to infer the star formation histories of these systems, $SFR(t)$.
Applying a new variational calculus maximum likelihood method which includes a
full Bayesian analysis and allows a non-parametric estimate of the function one
is solving for, we infer the star formation histories of the systems studied.
This method has the advantage of yielding an objective answer, as one need not
assume {\it a priori} the form of the function one is trying to recover. The
results are checked independently using Saha's $W$ statistic. The total
luminosities of the systems are used to normalize the results into physical
units and derive SN type II rates. We derive the luminosity weighted mean star
formation history of this sample of galaxies.

</DOC>
<DOC>
<DOCNO> 70866 </DOCNO>
Flavour Dynamics - Central Mysteries of the Standard Model


  After pointing out the amazing success of the CKM description in
accommodating the phenomenology of flavour changing neutral currents I review
the status of theoretical technologies for extracting CKM parameters from data.
I sketch novel directions, namely attempts to deal with quark-hadron duality in
a (semi)quantitative way and to develop a QCD description of two-body modes of
$B$ mesons. After commenting on predictions for $\epsilon ^{\prime}/\epsilon$
and CP asymmetries in B decays I address indirect probes for New Physics in
$D^0$ oscillations and CP violation, in $K_{\mu 3}$ decays and electric dipole
moments. I describe in which way searching for New Physics in B decays provides
an exciting adventure with novel challenges not encountered before.

</DOC>
<DOC>
<DOCNO> 150528 </DOCNO>
k-Gerbes, Line Bundles and Anomalies


  We use sets of trivial line bundles for the realization of gerbes. For
1-gerbes the structure arises naturally for the Weyl fermion vacuum bundle at a
fixed time. The Schwinger term is an obstruction in the triviality of a
1-gerbe.

</DOC>
<DOC>
<DOCNO> 70145 </DOCNO>
Matter effects in the D0-D0bar system


  We discuss the impact of matter effects in the D0-D0bar system. We show that
such effects could, in principle, be measured, but that they cannot be used to
probe the mass difference x_D or the lifetime difference y_D. This occurs
because the mixing effects and the matter effects decouple at short times. We
also comment briefly on the B systems.

</DOC>
<DOC>
<DOCNO> 170280 </DOCNO>
Full mechanical characterization of a cold damped mirror


  We describe an experiment in which we have used a cold damping feedback
mechanism to reduce the thermal noise of a mirror around its mechanical
resonance frequency. The monitoring of the brownian motion of the mirror allows
to apply an additional viscous force without any thermal fluctuations
associated. This scheme has been experimentally implemented with the radiation
pressure of an intensity-modulated laser beam. Large noise reductions, up to 30
dB, have been obtained. We have also checked the mechanical response of the
cold damped mirror, and monitored its transient evolution between the cooled
regime and the room temperature equilibrium. A simple theoretical model allows
to fully explain the experimental results. A possible application to the active
cooling of the violin modes in a gravitational-wave interferometer is
discussed.

</DOC>
<DOC>
<DOCNO> 68767 </DOCNO>
Pattern Formation in the Early Universe


  Systems that exhibit pattern formation are typically driven and dissipative.
In the early universe, parametric resonance can drive explosive particle
production called preheating. The fields that are populated then decay quantum
mechanically if their particles are unstable. Thus, during preheating, a
driven-dissipative system exists. We have shown previously that pattern
formation can occur in two dimensions in a self-coupled inflaton system
undergoing parametric resonance. In this paper, we provide evidence of pattern
formation for more realistic initial conditions in both two and three
dimensions. In the one-field case, we have the novel interpretation that these
patterns can be thought of as a network of domain walls. We also show that the
patterns are spatio-temporal, leading to a distinctive, but probably
low-amplitude peak in the gravitational wave spectrum. In the context of a
two-field model, we discuss putting power from resonance into patterns on
cosmological scales, in particular to explain the observed excess power at 100
h^{-1}Mpc, but why this seems unlikely in the absence of a period of
post-preheating inflation. Finally we note our model is similar to that of the
decay of DCCs and therefore pattern formation may also occur at RHIC and LHC.

</DOC>
<DOC>
<DOCNO> 85232 </DOCNO>
Evolution of perturbations in a domain wall cosmology


  A fluid of domain walls has an effective equation of state $p_w = -
{2/3}\rho_w$. This equation of state is qualitativelly in agreement with the
supernova type Ia observations. We exploit a cosmological model where the
matter content is given by a dust fluid and a domain wall fluid. The process of
formation of galaxies is essentially preserved. On the other hand, the
behaviour of the density contrast in the ordinary fluid is highly altered when
domain walls begin to dominate the matter content of the Universe. This domain
wall phase occurs at relative recent era, and its possible consequences are
discussed, specially concerning the Sachs-Wolfe effect.

</DOC>
<DOC>
<DOCNO> 8747 </DOCNO>
Collective Singlet Excitations and Evolution of Raman Spectral Weights


  We present a Raman light scattering study of the two-dimensional quantum spin
system SrCu2(BO3)2 and show that the magnetic excitation spectrum has a rich
structure, including several well-defined bound state modes at low temperature,
and a scattering continuum and quasielastic light scattering contributions at
high temperature. The key to the understanding of the unique features of
SrCu2(BO3)2 is the presence of strong interactions between well-localized
triplet excitations in the network of orthogonal spin dimers realized in this
compound. Based on our analysis of the Heisenberg model relevant for this
material, we argue that the collective excitations involving two and
three-particle singlet bound states have large binding energies and are
observed as well-defined peaks in the Raman spectrum.

</DOC>
<DOC>
<DOCNO> 116282 </DOCNO>
We can know more in double-slit experiment


  We show that we can know more than the orthodox view does, as one example, we
make a new analysis about double-slit experiment, and demonstrate that we can
measure the objective state of the particles passing through the two slits
while not destroying the interference pattern, the measurement method is to use
protective measurement.

</DOC>
<DOC>
<DOCNO> 120982 </DOCNO>
Why is the Fraction of Four-Image Radio Lens Systems So High?


  We investigate the frequency of two- and four-image gravitational lens
systems in the Jodrell-VLA Astrometric Survey (JVAS) and Cosmic Lens All-Sky
Survey (CLASS), and the possible implications for dark matter halo properties.
A simple lensing statistics model, which describes lens galaxies as singular
isothermal ellipsoids with a projected axis ratio distribution derived from the
surface brightness ellipticities of early-type galaxies in the Coma cluster, is
ruled out at the 98% level since it predicts too few four-image lenses (quads).
We consider a range of factors that may be increasing the frequency of radio
quads, including external shear fields, mass distributions flatter than the
light, shallow lensing mass profiles, finite core radii, satellite galaxies,
and alterations to the luminosity function for faint flat-spectrum radio
sources. We find that none of these mechanisms provide a compelling solution to
the quad problem on their own while remaining consistent with other
observational constraints.

</DOC>
<DOC>
<DOCNO> 11663 </DOCNO>
Nonperturbative study of the two-frequency sine-Gordon model


  The two-frequency sine-Gordon model is examined. The focus is mainly on the
case when the ratio of the frequencies is 1/2, given the recent interest in the
literature. We discuss the model both in a perturbative (form factor
perturbation theory) and a nonperturbative (truncated conformal space approach)
framework, and give particular attention to a phase transition conjectured
earlier by Delfino and Mussardo. We give substantial evidence that the
transition is of second order and that it is in the Ising universality class.
Furthermore, we check the UV-IR operator correspondence and conjecture the
phase diagram of the theory.

</DOC>
<DOC>
<DOCNO> 12859 </DOCNO>
On Hydrophobicity Correlations in Protein Chains


  We study the statistical properties of hydrophobic/polar model sequences with
unique native states on the square lattice. It is shown that this ensemble of
sequences differs from random sequences in significant ways in terms of both
the distribution of hydrophobicity along the chains and total hydrophobicity.
Whenever statistically feasible, the analogous calculations are performed for a
set of real enzymes, too.

</DOC>
<DOC>
<DOCNO> 117387 </DOCNO>
The nature of RXJ0052.1-7319


  The nature of the X-ray source RXJ0052.1-7319 is discussed from observational
data obtained from ROSAT observations performed in 1995 and 1996. An accurate
position is derived from ROSAT HRI observations performed in 1995. The 6" error
circle contains two OGLE microlensing optical variables of which one has
previously been identified with a 14.5 mag Be-type star in the Small Magellanic
Cloud. During the October 1996 observation RXJ0052.1-7319 was found to be
extremely bright (with a count rate of ~1.1+/-0.1 s^-1) and 15.3 second X-ray
pulsations have been discovered during this observation. This indicates for a
high-mass X-ray binary nature of the source. During the 1995 observation the
X-ray source detected at the position of RXJ0052.1-7319 was a factor 200
fainter. The corresponding luminosity has changed from 5.2x10^37 erg s^-1 to
2.6x10^35 erg s^-1 assuming SMC membership of the source. It is unclear whether
the so-far unidentified second optical variable contributes to the X-ray flux
of the source.

</DOC>
<DOC>
<DOCNO> 101093 </DOCNO>
Geometric Aspects of Mirror Symmetry


  The geometric aspects of mirror symmetry are reviewed, with an eye towards
future developments. Given a mirror pair (X,Y) of Calabi-Yau threefolds, the
best-understood mirror statements relate certain small corners of the moduli
spaces of X and of Y. We will indicate how one might go beyond such statements,
and relate the moduli spaces more globally. In fact, in the boldest version of
mirror symmetry (the Strominger-Yau-Zaslow conjecture), the Calabi-Yau
threefolds X and Y should be directly related to each other through a very
geometric construction.

</DOC>
<DOC>
<DOCNO> 10751 </DOCNO>
Fractional Diffusion based on Riemann-Liouville Fractional Derivatives


  A fractional diffusion equation based on Riemann-Liouville fractional
derivatives is solved exactly. The initial values are given as fractional
integrals. The solution is obtained in terms of $H$-functions. It differs from
the known solution of fractional diffusion equations based on fractional
integrals. The solution of fractional diffusion based on a Riemann-Liouville
fractional time derivative does not admit a probabilistic interpretation in
contrast with fractional diffusion based on fractional integrals. While the
fractional initial value problem is well defined and the solution finite at all
times its values for $t\to 0$ are divergent.

</DOC>
<DOC>
<DOCNO> 119572 </DOCNO>
Kinematic Age Estimates for 4 Compact Symmetric Objects from the


  Based on multi-epoch observations at 15 and 43 GHz with the Very Long
Baseline Array (VLBA) we detect significant angular expansions between the two
hot spots of 4 Compact Symmetric Objects (CSOs). From these relative motions we
derive kinematic ages of between 300 and 1200 years for the radio emission.
These ages lend support to the idea that CSOs are produced in a recent phase of
activity. These observations also allow us to study the evolution of the hot
spots dynamically in individual sources. In all 4 sources the hot spots are
separating along the source axis, but in 1031+567 the tip of one hot spot
appears to be moving almost orthogonally to the source axis. Jet components,
seen in 3 of the 4 sources observed, are found to be moving relativistically
outward from the central engines towards the more slowly moving hot spots.

</DOC>
<DOC>
<DOCNO> 117945 </DOCNO>
The Dependence of Tidally-Induced Star Formation on Cluster Density


  A survey of H alpha emission in 320 spiral galaxies in 8 nearby clusters
shows an enhancement of circumnuclear starburst emission with increasingly rich
clusters. These observations provide convincing evidence that spirals have been
transformed into S0s in clusters predominantly by tidal forces, a picture fully
in accord with the most recent numerical simulations of clusters. For the
richest clusters, the enhancement of starburst emission is greater than would
be expected on the basis of increasing galaxy surface density alone, which may
explain the anomalous result for the type-galaxy surface density relation found
for low richness clusters at intermediate redshift.

</DOC>
<DOC>
<DOCNO> 70282 </DOCNO>
Can Neutrinos Probe Extra Dimensions?


  We conjecture that the topological structure of the gauge symmetries required
by the Calabi-Yau vacuum and the dualities in string/D-branes considered in the
world with some additional dimensions can lead to an extension of the main
principles of the Special Theory of Relativity. The link between the
topological structure of the vacuum and the, hierarchy of the gauge symmetries
could be checked by the existence of the ``almost massless'', ''sterile''
particles. These particles could have flying properties different from the
standard predictions of the STR. It is natural to consider this property for
neutrinos, known up to now ``$U(1)_{em}$ sterile'' particles. Here we discuss
two such effects depending on the possible existence of large and/or small
extra dimensions and what is the maximal speed for both cases.
  The effect of large extra dimensions can be directly connected with the
existence of a hidden boost, $c_{hid} >> c_{em}$, excited by new global
dimensions and can lead to the monotonous rise of the neutrino velocity at high
energies, $v_{\nu} > c$.
  The effect of small extra dimensions, universal with respect to all
particles, can be connected with the gravitation recoils of the propagation of
neutrino in the space-time vacuum-foam and it leads to the effect of
diminishing the neutrino velocity at high energies.
  We propose to check these conjectures for neutrinos of different energies and
species. Limits for existing neutrino data and expected sensitivities of
possible experiments for accelerator - produced neutrinos are considered. It is
pointed out that CERN has the unique opportunity of measuring the indicated
effects.

</DOC>
<DOC>
<DOCNO> 101665 </DOCNO>
On elements in algebras having finite number of conjugates


  Let $R$ be a ring with unity and $U(R)$ its group of units. Let $\Delta
U=\{a\in U(R)\mid [U(R):C_{U(R)}(a)]<\infty\}$ be the $FC$-radical of $U(R)$
and let $\nabla(R)=\{a\in R\mid [U(R):C_{U(R)}(a)]<\infty\}$ be the
$FC$-subring of $R$.
  An infinite subgroup $H$ of $U(R)$ is said to be an $\omega$-subgroup if the
left annihilator of each nonzero Lie commmutator $[x,y]$ in $R$ contains only
finite number of elements of the form $1-h$, where $x,y \in R$ and $h\in H$. In
the case when $R$ is an algebra over a field $F$, and $U(R)$ contains an
$\omega$-subgroup, we describe its $FC$-subalgebra and the $FC$-radical. This
paper is an extension of [1].

</DOC>
<DOC>
<DOCNO> 68675 </DOCNO>
Indirect constraints on R-parity violating stop couplings


  It was recently claimed that single stop production at the Tevatron,
occurring via R-parity (and baryon number) violating couplings, could lead to
observable signals. In this talk I present some results of a work in progress,
showing that rare B decays and K0-K0bar mixing strongly constrain such a
possibility.

</DOC>
<DOC>
<DOCNO> 84301 </DOCNO>
Spin foams as Feynman diagrams


  It has been recently shown that a certain non-topological spin foam model can
be obtained from the Feynman expansion of a field theory over a group. The
field theory defines a natural ``sum over triangulations'', which removes the
cut off on the number of degrees of freedom and restores full covariance. The
resulting formulation is completely background independent: spacetime emerges
as a Feynman diagram, as it did in the old two-dimensional matrix models. We
show here that any spin foam model can be obtained from a field theory in this
manner. We give the explicit form of the field theory action for an arbitrary
spin foam model. In this way, any model can be naturally extended to a sum over
triangulations. More precisely, it is extended to a sum over 2-complexes.

</DOC>
<DOC>
<DOCNO> 13182 </DOCNO>
Dynamical Properties of one dimensional Mott Insulators


  At low energies the charge sector of one dimensional Mott insulators can be
described in terms of a quantum Sine-Gordon model. Using exact results derived
from integrability it is possible to determine dynamical properties like the
frequency dependent optical conductivity. We compare the exact results to
perturbation theory and renormalisation group calculations. We also discuss the
application of our results to experiments on quasi-1D organic conductors.

</DOC>
<DOC>
<DOCNO> 121566 </DOCNO>
Do mergers make (normal) ellipticals?


  Under the merger hypothesis, elliptical galaxies are built through mergers of
gas-rich spirals. However, the relative paucity of HI in most normal
ellipticals demands significant processing of atomic gas into other forms if
this process is to be viable. Here I present a few qualitative remarks on how
the properties of merger-spawned ellipticals might depend on the (evolving) gas
content of the progenitor disks, then turn to a more quantitative study of the
constraints provided by the nuclear properties of ellipticals and merger
remnants.

</DOC>
<DOC>
<DOCNO> 122240 </DOCNO>
Astrophysics of the Soft Gamma Repeaters and Anomalous X-Ray Pulsars


  I summarize the recent advances in our understanding of the Soft Gamma
Repeaters: in particular their spin behavior, persistent emission and
hyper-Eddington outbursts. The giant flares on 5 March 1979 and 27 August 1998
provide compelling physical evidence for magnetic fields stronger than 10
B_{QED} = 4.4 x 10^{14} G, consistent with the rapid spindown detected in two
of these sources. The persistent X-ray emission and variable spindown of the
6-12 s Anomalous X-ray Pulsars are compared and contrasted with those of the
SGRs, and the case made for a close connection between the two types of
sources. Their collective properties point to the existence of {\it magnetars}:
neutron stars in which a decaying magnetic field (rather than accretion or
rotation) is the dominant source of energy for radiative and particle
emissions. Observational tests of the magnetar model are outlined, along with
current ideas about the trigger of SGR outbursts, new evidence for the trapped
fireball model, and the influence of QED processes on X-ray spectra and
lightcurves. A critical examination is made of coherent radio emission from
bursting strong-field neutron stars. I conclude with an overview of the genetic
connection between neutron star magnetism and the violent fluid motions in a
collapsing supernova core.

</DOC>
<DOC>
<DOCNO> 151734 </DOCNO>
Finite action, holographic conformal anomaly and quantum brane-worlds in


  We report our recent results concerning d5 gauged supergravity (dilatonic
gravity) considered on AdS background. The finite action on such background as
well as d4 holographic conformal anomaly (via AdS/CFT correspondence) are
found. In such formalism the bulk potential is kept to be arbitrary, dilaton
dependent function. Holographic RG in such theory is briefly discussed. d5 AdS
brane-world Universe induced by quantum effects of brane CFT is constructed.
Such brane is spherical, hyperbolic or flat one. Hence, the possibility of
quantum creation of inflationary brane-world Universe is shown.

</DOC>
<DOC>
<DOCNO> 7953 </DOCNO>
The Ginzburg regime and its effects on topological defect formation


  The Ginzburg temperature has historically been proposed as the energy scale
of formation of topological defects at a second order symmetry breaking phase
transition. More recently alternative proposals which compute the time of
formation of defects from the critical dynamics of the system, have been
gaining both theoretical and experimental support. We investigate, using a
canonical model for string formation, how these two pictures compare. In
particular we show that prolonged exposure of a critical field configuration to
the Ginzburg regime results in no substantial suppression of the final density
of defects formed. These results dismiss the recently proposed role of the
Ginzburg regime in explaining the absence of topological defects in 4He
pressure quench experiments.

</DOC>
<DOC>
<DOCNO> 99357 </DOCNO>
Equivariant Kasparov theory and generalized homomorphisms


  Let G be a locally compact group. We describe elements of KK^G (A,B) by
equivariant homomorphisms, following Cuntz's treatment in the non-equivariant
case. This yields another proof for the universal property of KK^G: It is the
universal split exact stable homotopy functor.
  To describe a Kasparov triple (E, phi, F) by an equivariant homomorphism, we
have to arrange for the Fredholm operator F to be equivariant. This can be done
if A is of the form K(L^2G) otimes A' and more generally if the group action on
A is proper in the sense of Rieffel and Exel.

</DOC>
<DOC>
<DOCNO> 122085 </DOCNO>
Precision Measurements of the 7Be(p,gamma)8B Reaction with Radioactive


  The 7Be(p,gamma)8B reaction is one of the major source of uncertainties in
estimating the 8B solar neutrino flux and is critical for undertsanding the
Solar Neutrino Problem and neutrinos. The main source of uncertainty is the
existence of conflicting data with different absolute normalization. Attempts
to measure this reaction rate with 7Be beams are under way by the UConn-LLN
collaboration, and we discuss a newly emerging method to extract this cross
section from the Coulomb dissociation of the radioactive beam of 8B. We discuss
some of the issues relevant for this study including the question of the E2
contribution to the Coulomb dissociation process which was measured to be
small. The Coulomb dissociation appears to provide a viable alternative method
for measuring the 7Be(p,gamma)8B reaction rate, with a weighted average of the
RIKEN1, RIKEN2 and GSI1 published results of S17(0) = 19.4 +/- 1.3 eV-b.

</DOC>
<DOC>
<DOCNO> 69416 </DOCNO>
Flavour non-conservation in goldstino interactions


  We point out that the interactions of goldstinos with matter supermultiplets
are a potential source of flavour violation, if fermion and sfermion mass
matrices are not aligned and supersymmetry is spontaneously broken at a low
scale. We study the impact of those couplings on low-energy processes such as
\mu \to e \gamma, \mu \to eee, K \to \mu^+ \mu^-, K-\ov{K} transitions and
analogous ones. Moreover, we address the issue of flavour violation in
low-energy processes involving two goldstinos and two matter fermions,
generalizing earlier results obtained in the flavour-conserving case.

</DOC>
<DOC>
<DOCNO> 119963 </DOCNO>
The Properties of the X-Ray-Selected EMSS Sample of BL Lac Objects


  We present updated and complete radio, optical and X-ray data for BL Lacs in
the Einstein Medium Sensitivity Survey (EMSS). The complete "M91" sample first
presented in Morris et al. is updated to include 26 BL Lacs in total and we
define a new, virtually complete sample consisting of 41 EMSS BL Lacs (the
"D40" sample). New high signal-to-noise, arcsecond-resolution VLA observations
are also presented for eleven EMSS BL Lacs, completing VLA observations of the
M91 sample. The addition of four new objects, as well as updated X-ray flux and
redshift information, has increased the v/v_max value for the M91 sample to
0.399\pm0.057; and v/v_max = 0.427\pm0.045 for the newly defined D40 sample. In
conjunction with other studies of X-ray-selected BL Lac (XBL) samples, these
results solidify negative evolution for XBLs, especially for more extreme
high-energy-peaked BL Lacs. The observed v/v_max, spectral and radio properties
of XBLs are completely consistent with being the beamed population of
low-luminosity, FR-1 radio galaxies. However, our VLA observations do confirm
that XBLs are too core-dominated to be consistent with a beamed population of
FR-1s seen at intermediate angles, as suggested by the unified model, if XBLs
have moderate outflow velocities (gamma approx 5).

</DOC>
<DOC>
<DOCNO> 69547 </DOCNO>
Phenomenological aspects of nonstandard supersymmetry breaking terms


  In realistic supersymmetric models, very small hard supersymmetry breaking
terms generally appear. Some of them violate baryon and/or lepton number. We
discuss their possible applications to proton decay and generation of neutrino
masses.

</DOC>
<DOC>
<DOCNO> 101552 </DOCNO>
Translation lengths in Out(F_n)


  We prove that all elements of infinite order in $Out(F_n)$ have positive
translation lengths; moreover, they are bounded away from zero. Consequences
include a new proof that solvable subgroups of $Out(F_n)$ are finitely
generated and virtually abelian and the new result that such subgroups are
quasi-convex.

</DOC>
<DOC>
<DOCNO> 117551 </DOCNO>
Abundances in Very Metal-Poor Stars


  Metal-poor stars provide information on the characteristics and chemical
evolution of the halo population of the Galaxy, the first epoch of star
formation and Galaxy formation (not just locally but with relevance to
high-redshift objects), and big bang nucleosynthesis. This review looks at
recent developments in this subject.

</DOC>
<DOC>
<DOCNO> 70185 </DOCNO>
Study of $B_{s,d}\to l^+l^-\gamma$ Decays


  We study the decays of $B_{s,d} \to l^+ l^- \gamma (l=e, \mu,\tau)$ within
the light-front model. We calculate the tensor type form factors and use these
form factors to evaluate the decay branching ratios. We find that, in the
standard model, the branching ratios of $B_{s(d)} \to \l^+ \l^- \gamma$ ($\l=e,
\mu,\tau$) are $7.1\times 10^{-9}$ ($1.5\times 10^{-10}$), $8.3\times 10^{-9}$
($1.8\times 10^{-10}$), $1.6\times 10^{-8}$ ($6.2\times 10^{-10}$),
respectively.

</DOC>
<DOC>
<DOCNO> 13253 </DOCNO>
Dissipationless Spin Transport in Thin Film Ferromagnets


  Metallic thin film ferromagnets generically possess spiral states that carry
dissipationless spin currents. We relate the critical values of these
supercurrents to micromagnetic material parameters, identify the circumstances
under which the supercurrents will be most robust, and propose experiments
which could reveal this new collective transport behavior.

</DOC>
<DOC>
<DOCNO> 121770 </DOCNO>
Two Highly Polarized QSOs Discovered by 2MASS


  We present optical observations of two remarkable new AGN discovered by the
Two-Micron All Sky Survey. Both are classified as QSOs based on their optical
spectra, near-IR colors, and near-IR and [O III]5007 luminosities, but their
optical polarizations are among the highest seen for non-blazar AGN;
approaching 15% for 2MASSI J151653.2+190048. The polarized light spectrum for
each object exhibits broad Balmer emission lines, but lacks the narrow lines
that are evident in the total light spectrum. This is most pronounced for the
Type-1.5 object 2MASSI J165939.7+183436, where broad lines dominate only in
polarized light. The polarization properties of these AGN suggest that dust
near the nucleus at least partially obscures the AGN and that material probably
intermixed with the narrow line-emitting gas scatters nuclear light into our
line of sight. These QSOs illustrate the variety of highly polarized AGN that
have been missed by traditional optical search techniques, and demonstrate that
such objects are exposed by surveys in the near-IR.

</DOC>
<DOC>
<DOCNO> 12991 </DOCNO>
First principles study of the adsorption of C60 on Si(111)


  The adsorption of C60 on Si(111) has been studied by means of
first-principles density functional calculations.
   A 2x2 adatom surface reconstruction was used to simulate the terraces of the
7x7 reconstruction.
   The structure of several possible adsorption configurations was optimized
using the ab initio atomic forces, finding good candidates for two different
adsorption states observed experimentally.
   While the C60 molecule remains closely spherical, the silicon substrate
appears quite soft, especially the adatoms, which move substantially to form
extra C-Si bonds, at the expense of breaking Si-Si bonds.
   The structural relaxation has a much larger effect on the adsorption
energies, which strongly depend on the adsorption configuration, than on the
charge transfer.

</DOC>
<DOC>
<DOCNO> 119383 </DOCNO>
FUSE Observations of the Low-Redshift Lyman-beta Forest


  We describe a moderate-resolution (20-25 km/s) FUSE study of the low-redshift
intergalactic medium. We report on studies of 7 extragalactic sightlines and 12
Ly-beta absorbers that correspond to Ly-alpha lines detected by HST/GHRS and
STIS. These absorbers appear to contain a significant fraction of the low-z
baryons and were a major discovery of the HST spectrographs. Using FUSE data,
with 40 mA (4-sigma) Lyb detection limits, we have employed the equivalent
width ratio of Lyb/Lya and occasionally higher Lyman lines, to determine the
doppler parameter, b, and accurate column densities, N(HI), for moderately
saturated lines. We detect Lyb absorption corresponding to all Lya lines with
EW > 200 mA. The Lyb/Lya ratios yield a preliminary distribution function of
doppler parameters, with mean <b> = 31.4 +/- 7.4 km/s and median b = 28 km/s,
comparable to values at redshifts z = 2.0-2.5. If thermal, these b-values
correspond to T(HI) ~ 50,000 K, although the inferred doppler parameters are
considerably less than the widths derived from Lya profile fitting,
<b(dopp)/b(width)> = 0.52. The typical increase in column density over that
derived from profile fitting is Delta[log N(HI)] = 0.3, but ranges up to 1.0
dex. Our data suggest that the low-z Lya absorbers contain sizable non-thermal
motions or velocity components in the line profile, perhaps arising from
cosmological expansion and infall.

</DOC>
<DOC>
<DOCNO> 101008 </DOCNO>
Affine surfaces with $AK(S)=\Bbb C.$


  In this paper we give a description of hypersurfaces with trivial ring
$AK(S)$, introduced by the second author as following. Let $X$ be an affine
variety and let $G(X)$ be the group generated by all $\Bbb {C}^+$-actions on
$X$. Then $AK(X)$ is the subring of all regular $G(X)-$ invariant functions on
$X.$ We show that a smooth affine surface $S$ with $AK(S)=\Bbb C$ is
quasihomogeneous and so may be obtained from a smooth rational projective
surface by deleting a divisor of special form, which is called a ``zigzag''. We
denote by $A$ the set of all such surfaces, and by $H$ those which have only
three components in the zigzag. We prove that for a surface $S \in A$ the
following statements are equivalent:
 1. $S$ is isomorphic to a hypersurface;
 2. $S$ is isomorphic to a hypersurface, defined by equation $xy=p(z)$ in $\Bbb
{C}^3 ,$ where $p$ is a polynomial with simple roots only;
 3. $S$ admits a fixed-point free $\Bbb {C}^+$- action;
 4. $S\in H.$ Moreover, if $S_1 $ belongs to $H,$ and $S_2$ does not, then
$S_1\times \Bbb {C}^k\not\cong S_2\times \Bbb {C}^k$ for any $k\in\Bbb N$.

</DOC>
<DOC>
<DOCNO> 101685 </DOCNO>
Remarks on the similarity degree of an operator algebra


  The "similarity" degree of a unital operator algebra $A$ was defined and
studied in two recent papers of ours, where in particular we showed that it
coincides with the "length" of an operator algebra. This paper brings several
complements: we give direct proofs (with slight improvements) of several known
facts on the length which were only known via the degree, and we show that the
length of a type $II_1$ factor with property $\Gamma$ is at most 5, improving
on a previous bound ($\le 44$) due to E. Christensen.

</DOC>
<DOC>
<DOCNO> 118315 </DOCNO>
A Serendipitous Search for High-Redshift Lyman alpha Emission: Two


  In the course of our ongoing search for serendipitous high-redshift Lyman
alpha (LyA) Emissionin deep archival Keck spectra, we discovered two very high
equivalent width (W_{obs} ~ 450A, 2-sigma) LyA emission line candidates at z ~3
in a moderate dispersion (R~1200) spectrogram. Both lines have low velocity
dispersions (sigma_v ~ 60 km/s) and deconvolved radii r ~ 1 kpc (h = 0.5). We
argue that the lines are LyA, and are powered by stellar ionization. The
surface density of robust, high equivalent width LyA candidates is estimated to
be ~3 \pm 2 per arcmin^2 per unit redshift at z ~ 3, consistent with the
estimate of Cowie etal (1998). The LyA emission line source characteristics are
consistent with the galaxies undergoing their first burst of star formation,
ie, with being primeval. Source sizes and velocity dispersions are comparable
to the theoretical primeval galaxy model of Lin and Murray (1992) based on the
inside-out, self-similar collapse of an isothermal sphere. In this model, star
formation among field galaxies is a protracted process. Galaxies are thought to
be able to display high equivalent widths for only the first few x 10 Myr. This
time is short in relation to the difference in look back times between z=3 and
z=4, and implies that a substantial fraction of strong line-emitting galaxies
at z=3 were formed at redshifts z < 4. We discuss the significance of
high-equivalent width LyA-emitting galaxies in terms of the emerging picture of
the environment, and the specific characteristics of primeval galaxy formation
at high redshift.

</DOC>
<DOC>
<DOCNO> 10246 </DOCNO>
The Replica Limit of Unitary Matrix Integrals


  We investigate the replica trick for the microscopic spectral density,
$\rho_s(x)$, of the Euclidean QCD Dirac operator. Our starting point is the
low-energy limit of the QCD partition function for $n$ fermionic flavors (or
replicas) in the sector of topological charge $\nu$. In the domain of the
smallest eigenvalues, this partition function is simply given by a U(n) unitary
matrix integral. We show that the asymptotic behavior of $\rho_s(x)$ for $x \to
\infty$ is obtained from the $n\to 0$ limit of this integral. The smooth
contributions to this series are obtained from an expansion about the replica
symmetric saddle-point, whereas the oscillatory terms follow from an expansion
about a saddle-point that breaks the replica symmetry. For $\nu =0$ we recover
the small-$x$ logarithmic singularity of the resolvent by means of the replica
trick. For half integer $\nu$, when the saddle point expansion of the U(n)
integral terminates, the replica trick reproduces the exact analytical result.
In all other cases only an asymptotic series that does not uniquely determine
the microscopic spectral density is obtained. We argue that bosonic replicas
fail to reproduce the microscopic spectral density. In all cases, the exact
answer is obtained naturally by means of the supersymmetric method.

</DOC>
<DOC>
<DOCNO> 150926 </DOCNO>
Various Modified Solutions of the Randall-Sundrum Model with the


  The Gauss-Bonnet interaction is the only consistent quadratic interaction
below the Planck scale in the Randall-Sundrum compactification. We study
various static and inflationary solutions including this Gauss-Bonnet
interaction.

</DOC>
<DOC>
<DOCNO> 72143 </DOCNO>
Beyond the standard model with B physics


  Extensions of the Standard Model may have significant effects on B physics
observables. Two examples of methods that may find such effects are reviewed:
Resolving discrete ambiguities in CP asymmetries and detecting right handed
currents in radiative B decays.

</DOC>
<DOC>
<DOCNO> 68222 </DOCNO>
Quantifying Baryon Stopping in High Energy Nuclear Collisions


  We propose a numerical definition for baryon stopping in relativistic heavy
ion collisions that is obtainable from final hadron rapidity distributions as
well as from bremsstrahlung measurements. Thus a new channel of communication
is opened between the two methods.

</DOC>
<DOC>
<DOCNO> 84239 </DOCNO>
Radiation flux and spectrum in the Vaidya collapse model


  We consider the quantization of a massless scalar field, using the geometric
optics approximation, in the background spacetime of a collapsing spherical
self-similar Vaidya star, which forms a black hole or a naked singularity. We
show that the outgoing radiation flux of the quantized scalar field diverges on
the Cauchy horizon. The spectrum of the produced scalar partcles is non-thermal
when the background develops a naked singularity. These results are analogous
to those obtained for the scalar quantization on a self-similar dust cloud.

</DOC>
<DOC>
<DOCNO> 7830 </DOCNO>
Critical properties of the double-frequency sine-Gordon model with


  We study the properties of the double-frequency sine--Gordon model in the
vicinity of the Ising quantum phase transition displayed by this model. Using a
mapping onto a generalised lattice quantum Ashkin-Teller model, we obtain
critical and nearly-off-critical correlation functions of various operators. We
discuss applications of the double-sine-Gordon model to one-dimensional
physical systems, like spin chains in a staggered external field and
interacting electrons in a staggered potential.

</DOC>
<DOC>
<DOCNO> 100463 </DOCNO>
On Fourier frames


  We solve the problem of Duffin and Schaeffer (1952) of characterizing those
sequences of real frequencies which generate Fourier frames. Equivalently, we
characterize the sampling sequences for the Paley-Wiener space. The key step is
to connect the problem with de Branges' theory of Hilbert spaces of entire
functions. We show that our description of sampling sequences permits us to
obtain a classical inequality of H. Landau as a consequence of Pavlov's
description of Riesz bases of complex exponentials and the John-Nirenberg
theorem. Finally, we discuss how to transform our description into a working
condition by relating it to an approximation problem for subharmonic functions.
By this approach, we determine the critical growth rate of a non-decreasing
function $\psi$ such that the sequence $\{\lambda_k\}_{k\in\Z}$ defined by
$\lambda_k+\psi(\lambda_k)=k$ is sampling.

</DOC>
<DOC>
<DOCNO> 14070 </DOCNO>
Doping dependence of the superconducting gap in Bi2Sr2CaCu2O{8 + delta}


  Bi2Sr2CaCu2O{8 + \delta} crystals with varying hole concentrations (0.12 < p
< 0.23) were studied to investigate the effects of doping on the symmetry and
magnitude of the superconducting gap. Electronic Raman scattering experiments
that sample regions of the Fermi surface near the diagonal (B_{2g}) and
principal axes (B_{1g}) of the Brillouin Zone have been utilized. The frequency
dependence of the Raman response function at low energies is found to be linear
for B_{2g} and cubic for B_{1g} (T< T_c). The latter observations have led us
to conclude that the doping dependence of the superconducting gap is consistent
with d_{x^2-y^2} symmetry, for slightly underdoped and overdoped crystals.
Studies of the pair-breaking peak found in the B_{1g} spectra demonstrate that
the magnitude of the maximum gap decreases monotonically with increasing hole
doping, for p > 0.12. Based on the magnitude of the B_{1g} renormalization, it
is found that the number of quasiparticles participating in pairing increases
monotonically with increased doping. On the other hand, the B_{2g} spectra show
a weak "pair-breaking peak" that follows a parabolic-like dependence on hole
concentration, for 0.12 < p < 0.23.

</DOC>
<DOC>
<DOCNO> 174540 </DOCNO>
Effect of the intermediate velocity emissions on the quasi-projectile


  The quasi-projectile (QP) properties are investigated in the Ar+Ni collisions
at 95 A.MeV taking into account the intermediate velocity emission. Indeed, in
this reaction, between 52 and 95 A.MeV bombarding energies, the number of
particles emitted in the intermediate velocity region is related to the overlap
volume between projectile and target. Mean transverse energies of these
particles are found particularly high. In this context, the mass of the QP
decreases linearly with the impact parameter from peripheral to central
collisions whereas its excitation energy increases up to 8 A.MeV. These results
are compared to previous analyses assuming a pure binary scenario.

</DOC>
<DOC>
<DOCNO> 69319 </DOCNO>
Renormalizable Abelian-projected effective gauge theory derived from


  We show that an effective Abelian gauge theory can be obtained as a
renormalizable theory from QCD in the maximal Abelian gauge. The derivation
improves in a systematic manner the previous version that was obtained by one
of the authors and was referred to as the Abelian-projected effective gauge
theory. This result supports the view that we can construct an effective
Abelian gauge theory from QCD without losing characteristic features of the
original non-Abelian gauge theory. In fact, it is shown that the effective
coupling constant in the resulting renormalizable theory has a
renormalization-scale dependence governed by the $\beta$-function that is
exactly the same as that of the original Yang-Mills theory, irrespective of the
choice of gauge fixing parameters of the maximal Abelian gauge and the
parameters used for identifying the dual variables. Moreover, we evaluate the
anomalous dimensions of the fields and parameters in the resultant theory. By
choosing the renormalized parameters appropriately, we can switch the theory
into an electric or a magnetic theory.

</DOC>
<DOC>
<DOCNO> 69678 </DOCNO>
Exclusive decays of Xi(QQ') baryons in NRQCD sum rules


  We perform a detailed study of semileptonic form-factors for the doubly heavy
baryons in the framework of three-point NRQCD sum rules. The analyis of spin
symmetry relations as well as numerical results on various exclusive decay
modes of doubly heavy baryons are given.

</DOC>
<DOC>
<DOCNO> 174527 </DOCNO>
Investigation of the Exclusive 3He(e,e'pp)n Reaction


  Cross sections for the 3He(e,e'pp)n reaction were measured over a wide range
of energy and three- momentum transfer. At a momentum transfer q=375 MeV/c,
data were taken at transferred energies omega ranging from 170 to 290 MeV. At
omega=220 MeV, measurements were performed at three q values (305, 375, and 445
MeV/c). The results are presented as a function of the neutron momentum in the
final-state, as a function of the energy and momentum transfer, and as a
function of the relative momentum of the two-proton system. The data at neutron
momenta below 100 MeV/c, obtained for two values of the momentum transfer at
omega=220 MeV, are well described by the results of continuum-Faddeev
calculations. These calculations indicate that the cross section in this domain
is dominated by direct two-proton emission induced by a one-body hadronic
current. Cross section distributions determined as a function of the relative
momentum of the two protons are fairly well reproduced by continuum-Faddeev
calculations based on various realistic nucleon-nucleon potential models. At
higher neutron momentum and at higher energy transfer, deviations between data
and calculations are observed that may be due to contributions of isobar
currents.

</DOC>
<DOC>
<DOCNO> 99491 </DOCNO>
Open sets satisfying systems of congruences


  A famous result of Hausdorff states that a sphere with countably many points
removed can be partitioned into three pieces A,B,C such that A is congruent to
B (i.e., there is an isometry of the sphere which sends A to B), B is congruent
to C, and A is congruent to (B union C); this result was the precursor of the
Banach-Tarski paradox. Later, R. Robinson characterized the systems of
congruences like this which could be realized by partitions of the (entire)
sphere with rotations witnessing the congruences. The pieces involved were
nonmeasurable. In the present paper, we consider the problem of which systems
of congruences can be satisfied using open subsets of the sphere (or related
spaces); of course, these open sets cannot form a partition of the sphere, but
they can be required to cover "most of" the sphere in the sense that their
union is dense. Various versions of the problem arise, depending on whether one
uses all isometries of the sphere or restricts oneself to a free group of
rotations (the latter version generalizes to many other suitable spaces), or
whether one omits the requirement that the open sets have dense union, and so
on. While some cases of these problems are solved by simple geometrical
dissections, others involve complicated iterative constructions and/or results
from the theory of free groups. Many interesting questions remain open.

</DOC>
<DOC>
<DOCNO> 119576 </DOCNO>
A Search for Environmental Effects on Type Ia Supernovae


  We use integrated colors and B and V absolute magnitudes of Type Ia supernova
(SN) host galaxies in order to search for environmental effects on the SN
optical properties. With the new sample of 44 SNe we confirm the conclusion by
Hamuy et al. (1996a) that bright events occur preferentially in young stellar
environments. We find also that the brightest SNe occur in the least luminous
galaxies, a possible indication that metal-poorer neighbourhoods produce the
more luminous events. The interpretation of these results is made difficult,
however, due to the fact that galaxies with younger stellar populations are
also lower in luminosity. In an attempt to remove this ambiguity we use models
for the line strengths in the absorption spectrum of five early-type galaxies,
in order to estimate metallicities and ages of the SN host galaxies. With the
addition of abundance estimates from nebular analysis of the emission spectra
of three spiral galaxies, we find possible further evidence that luminous SNe
are produced in metal-poor neighborhoods. Further spectroscopic observations of
the SN host galaxies will be necessary to test these results and assist in
disentangling the age/metallicity effects on Type Ia SNe.

</DOC>
<DOC>
<DOCNO> 152425 </DOCNO>
Remarks on twisted theories with matter


  We investigate some aspects of N=2 twisted theories with matter
hypermultiplets in the fundamental representation of the gauge group. A
consistent formulation of these theories on a general four-manifold requires
turning on a particular magnetic flux, which we write down explicitly in the
case of SU(2k). We obtain the blowup formula and show that the blowup function
is given by a hyperelliptic sigma-function with singular characteristic. We
compute the contact terms and find, as a corollary, interesting identities
between hyperelliptic Theta functions.

</DOC>
<DOC>
<DOCNO> 40615 </DOCNO>
Physics Case and Challenges for the Vertex Tracker at Future High Energy


  The physics programme of high energy e+e- linear colliders relies on the
accurate identification of fermions in order to study in details the profile of
the Higgs boson, search for new particles and probe the multi-TeV mass region
by means of precise electro-weak measurements and direct searches.

</DOC>
<DOC>
<DOCNO> 13161 </DOCNO>
Jahn-Teller, Charge and Magnetic Ordering in half-doped Manganese Oxides


  The phase diagram of half-doped manganite systems of formula
A_{0.5}A'_{0.5}MnO_3 is investigated within a single-orbital model
incorporating magnetic double-exchange and superexchange, together with
intersite Coulomb and electron-lattice interactions. Strong Jahn-Teller and
breathing mode deformations compete together and result in shear lattice
deformations. The latters stabilize the charge-ordered CE-type phase, which
undergo first-order transitions with temperature or magnetic field to either
Ferromagnetic metallic or Paramagnetic insulating phases. An essential feature
is the self-consistent screening of Coulomb and electron-phonon interactions in
the ferromagnetic phase.

</DOC>
<DOC>
<DOCNO> 10704 </DOCNO>
Liquid-liquid equilibrium for monodisperse spherical particles


  A system of identical particles interacting through an isotropic potential
that allows for two preferred interparticle distances is numerically studied.
When the parameters of the interaction potential are adequately chosen, the
system exhibits coexistence between two different liquid phases (in addition to
the usual liquid-gas coexistence). It is shown that this coexistence can occur
at equilibrium, namely, in the region where the liquid is thermodynamically
stable.

</DOC>
<DOC>
<DOCNO> 99426 </DOCNO>
Symbolic computation of the roots of any polynomial with integer


  The roots of any polynomial of degree m with integer coefficients, can be
computed by manipulation of sequences made from 2m distinct symbols and
counting the different symbols in the sequences. This method requires only
'primitive' operations like replacement of sequences and counting of symbols.
No calculations using 'advanced' operations like multiplication, division,
logarithms etc. are needed. The method can be implemented as a geometric
construction of roots of polynomials to arbitrary accuracy using only a
straight edge, a compass, and pencils of 2m different colors. In particular,
the ancient problem of the "doubling of cube" is soluble asymptotically by the
above-mentioned construction. This method, by which a cube can be doubled,
albeit, in infinite steps, is probably the closest to the original problem of
construction using only a straight edge and compass in a finite number of
steps.
  Moreover, to every polynomial of degree m over the field of rationals, can be
associated an m-term recurrence relation for generating integer sequences. A
set of m such sequences, which together exhibit interesting properties related
to the roots of the polynomial, can be obtained if the m initial terms of each
of these m sequences is chosen in a special way using a matrix associated with
the polynomial. Only two of these integer sequences need to be computed to
obtain the real root having the largest absolute value. Since this method
involves only integers, it is faster than the conventional methods using
floating-point arithmetic.

</DOC>
<DOC>
<DOCNO> 120677 </DOCNO>
Determining the Microlens Mass Function from Quasar Microlensing


  The first investigations of the response of the microlensing magnification
pattern (at an optical depth of order unity) to the mass function of the
microlenses found that the resulting statistics depend only on the mean
microlens mass <m>. In particular the mean microlensing caustic crossing rate
was found to be proportional to the squareroot of <m>. We show that while this
is true in the limit of mass functions with a narrow range of mass, in general
the magnification pattern shows structure that reflects the contribution to the
optical depth of microlenses with different masses. We present a better
approximation, relating the microlens mass function to light-curve statistics.
We show that the variability statistics of quasar microlensing light-curves can
(in principle) be inverted to obtain the mass function of the microlenses in
the mass range over which the mass density remains comparable, ie. p(m)dm~C/m.
A preliminary analysis of the structure function for Q2237+0305 suggests that
there is not a significant contribution to the optical depth from very low mass
objects (0.001 solar mass). However observations of multiple microlensed
quasars for a period of ~20 years may in the future yield a detailed p(m)dm. In
the mass range where the number density is comparable, ie. p(m)dm~const., the
distribution of flux factors could be inverted to find the microlens mass
function. This may be used as a probe of the abundance of planets with orbital
radii >100 AU.

</DOC>
<DOC>
<DOCNO> 122500 </DOCNO>
Astrophysical implications of gravitational microlensing of


  Astrophysical implications of gravitational microlensing of gravitational
waves emitted by rotating neutron stars (NSs) are investigated. In particular,
attention is focused on the following situations: i) NSs in the galactic bulge
lensed by a central black hole of $2.6\times 10^6 M_{\odot}$ or by stars and
MACHOs distributed in the galactic bulge, disk and halo between Earth and the
sources; ii) NSs in globular clusters lensed by a central black hole of $\sim
10^3 M_{\odot}$ or by stars and MACHOs distributed throughout the Galaxy. The
detection of such kind of microlensing events will give a unique opportunity
for the unambiguous mapping of the central region of the Galaxy and of globular
clusters. In addition, the detection of such events will provide a new test of
the General Theory of Relativity. Gravitational microlensing will, moreover,
increase the challenge of detecting gravitational waves from NSs.

</DOC>
<DOC>
<DOCNO> 84747 </DOCNO>
On Adelic Strings


  New approach to p-adic and adelic strings, which takes into account that not
only world sheet but also Minkowski space-time and string momenta can be p-adic
and adelic, is formulated. p-Adic and adelic string amplitudes are considered
within Feynman's path integral formalism. The adelic Veneziano amplitude is
calculated. Some discreteness of string momenta is obtained. Also, adelic
coupling constant is equal to unity.

</DOC>
<DOC>
<DOCNO> 84739 </DOCNO>
A note on topological brane theories


  We consider the theory of closed $p$-branes propagating on
$(p+1)$-dimensional space-time manifolds. This theory has no local degrees of
freedom. Here we study its canonical and BRST structures of the theory. In the
case of locally flat backgrounds one can show that the $p$-brane theory is
related to another known topological field theory. In the general situation
some equivalent actions can also be written for the topological $p$-brane
theory.

</DOC>
<DOC>
<DOCNO> 84263 </DOCNO>
Computing radiation from Kerr black holes: Generalization of the


  As shown by Teukolsky, the master equation governing the propagation of weak
radiation in a black hole spacetime can be separated into four ordinary
differential equations, one for each spacetime coordinate. (``Weak'' means the
radiation's amplitude is small enough that its own gravitation may be
neglected.) Unfortunately, it is difficult to accurately compute solutions to
the separated radial equation (the Teukolsky equation), particularly in a
numerical implementation. The fundamental reason for this is that the Teukolsky
equation's potentials are long ranged. For non-spinning black holes, one can
get around this difficulty by applying transformations which relate the
Teukolsky solution to solutions of the Regge-Wheeler equation, which has a
short-ranged potential. A particularly attractive generalization of this
approach to spinning black holes for gravitational radiation (spin weight s =
-2) was given by Sasaki and Nakamura. In this paper, I generalize Sasaki and
Nakamura's results to encompass radiation fields of arbitrary integer spin
weight, and give results directly applicable to scalar (s = 0) and
electromagnetic (s = -1) radiation. These results may be of interest for
studies of astrophysical radiation processes near black holes, and of programs
to compute radiation reaction forces in curved spacetime.

</DOC>
<DOC>
<DOCNO> 69923 </DOCNO>
Neutrino Masses at v^{3/2}


  Theories in which neutrino masses are generated by a conventional see-saw
mechanism generically yield masses which are O(v^2) in units where M_{Pl}=1,
which is naively too small to explain the results from SuperKamiokande. In
supersymmetric theories with gravity mediated supersymmetry breaking, the
fundamental small parameter is not v/M_{Pl}, but m_I/M_{Pl}, where m_I is the
scale of supersymmetry breaking in the hidden sector. We note that
m_I^3/M_{Pl}^2 is only slightly too large to explain SuperKamiokande, and
present two models that achieve neutrino masses at this order in m_I, one of
which has an additional suppression lambda_tau^2, while the other has
additional suppression arising from a loop factor. The latter model shares a
great deal of phenomenology with a class of models previously explored,
including the possibility of viable sneutrino dark matter.

</DOC>
<DOC>
<DOCNO> 9599 </DOCNO>
Insulator-metal transition in high-T$_c$ superconductors as result of


  The mechanism of -U center formation in high-$T_{c}$ superconductors (HTS)
with doping is considered. It is shown that the transition of HTS from
insulator to metal passes through the particular dopant concentration range
where the local transfer of singlet electron pairs from oxygen ions to pairs of
neighboring cations (-U centers) are allowed while the single-electron
transitions are still forbidden. We believe it is this concentration range that
corresponds to the region of high-Tc superconductivity and the interelectron
attraction results from the interaction of electron pairs with -U centers.
Additional hole carriers are generated as the result of singlet electron pair
transitions from oxygen ions to -U-centers. The orbitals of the arising singlet
hole pairs are localized in the nearest vicinity of -U center. In such a system
the hole conductivity starts up at the dopant concentration exceeding the
classical 2D-percolation threshold for singlet hole pair orbitals. In the
framework of the proposed model the phase diagram Ln-214 HTS compounds is
constructed. The remarkable accord between calculated and experimental phase
diagrams may be considered as the confirmation of the supposed model. The main
features of hole carriers in HTS normal state are found to be the nondegenerate
distribution and the dominant contribution of electron-electron scattering to
the hole carrier relaxation processes. Various experimentally observed
anomalies of HTS properties are shown to be the consequences of the
above-mentioned features. The conclusion is made that HTS compounds are the
special class of solids where the unusual mechanism of superconductivity
different from BCS is realized.

</DOC>
<DOC>
<DOCNO> 71196 </DOCNO>
LSND, SN1987A, and CPT Violation


  We point out that neutrino events observed at Kamiokande and IMB from SN1987A
disfavor the neutrino oscillation parameters preferred by the LSND experiment.
For $\Delta m^2 > 0$ (the light side), the electron neutrinos from the
neutronization burst would be lost, while the first event at Kamiokande is
quite likely to be due to an electron neutrino. For $\Delta m^2 < 0$ (the dark
side), the average energy of the dominantly $\bar{\nu}_e$ events is already
lower than the theoretical expectations, which would get aggravated by a
complete conversion from $\bar{\nu}_\mu$ to $\bar{\nu}_e$. If taken seriously,
the LSND data are disfavored independent of the existence of a sterile
neutrino. A possible remedy is CPT violation, which allows different mass
spectra for neutrinos and anti-neutrinos and hence can accommodate atmospheric,
solar and LSND data without a sterile neutrino. If this is the case, Mini-BooNE
must run in $\bar{\nu}$ rather than the planned $\nu$ mode to test the LSND
signal. We speculate on a possible origin of CPT violation.

</DOC>
<DOC>
<DOCNO> 102890 </DOCNO>
Euler characteristics of theta divisors of Jacobians for spectral curves


  We show how to calculate the Euler characteristic of an affine Jacobi variety
of a spectral curve from its defining equations.

</DOC>
<DOC>
<DOCNO> 178589 </DOCNO>
Cross sections for Coulomb and nuclear breakup of three-body halo nuclei


  All possible dissociation cross sections for the loosely bound three-body
halo nuclei $^6$He (n+n+$\alpha$) and $^{11}$Li (n+n+$^{9}$Li) are computed as
functions of target and beam energy. Both Coulomb and nuclear interactions are
included in the same theoretical framework. The measurements agree with the
calculations for energies above 100 Mev/nucleon. The largest cross sections
correspond to final states with zero or three particles for heavy and with two
neutrons for light targets.

</DOC>
<DOC>
<DOCNO> 116785 </DOCNO>
Measurement of the 21Ne Zeeman frequency shift due to Rb-21Ne collisions


  We compared the frequency shift of the 21Ne Zeeman resonance induced by
polarized Rb vapor to the shift induced in the 3He Zeeman resonance. The 3He/Rb
shift has recently been measured with high precision, permitting the conversion
of our differential measurement to an absolute value for the 21Ne/Rb shift. We
report a value of K = 31.8 +/- 2.8 for the Rb/21Ne enhancement factor at a
temperature of 124.8 +/- 1.9 C. We propose high-precision differential contact
shift measurements, the absolute accuracy of which would be limited by the
error in the 3He contact shift.

</DOC>
<DOC>
<DOCNO> 122070 </DOCNO>
Anatomy of giant spiral galaxies


  We present B and I band photometry, gas and star kinematics and 3D modelling
of 7 giant spiral galaxies. The stellar systems studied have morphological
types spanning from S0/a to Sc and absolute magnitudes from -20.6 to -22.5.
  The spectra have been collected with the spectrographs Boller & Chivens and
EFOSC2 of the 2.2m ESO-MPI telescope. Images have been taken with the same
telescope.
  The models fit simultaneously the photometric and kinematics data using a
disk+bulge tridimensional model. The distribution of luminous matter, coming
from the fit of the photometric data is compared with the distribution of total
matter derived from the velocity dispersion and velocity curves.
  The intrinsic properties of these galaxies, such as the disk/bulge mass
ratio, the total mass and the scale length of the galaxy components are
presented and discussed.

</DOC>
<DOC>
<DOCNO> 99865 </DOCNO>
Irreducible Representations of Braid Groups of corank two


  This paper is the first part of a series of papers aimed at improving the
classification by Formanek of the irreducible representations of Artin braid
groups of small dimension. In this paper we classify all the irreducible
complex representations $\rho$ of Artin braid group $B_n$ with the condition
$rank (\rho (\sigma_i)-1)=2$ where $\sigma_i$ are the standard generators. For
$n \geq 7$ they all belong to some one-parameter family of $n$-dimensional
representations.

</DOC>
<DOC>
<DOCNO> 70544 </DOCNO>
The Delta I=1/2 rule and epsilon'/epsilon


  The $\Delta I=1/2$ rule and direct CP violation $\epsilon'/\epsilon$ in kaon
decays are studied within the framework of the effective Hamiltonian approach
in conjunction with generalized factorization for hadronic matrix elements.

</DOC>
<DOC>
<DOCNO> 118443 </DOCNO>
Effects of Photospheric Temperature Inhomogeneities on Lithium Abundance


  Based on detailed 2D radiation hydrodynamics (RHD) simulations, we have
investigated the effects of photospheric temperature inhomogeneities induced by
convection on spectroscopic determinations of the lithium abundance.
Computations have been performed both for the solar case and for a metal-poor
dwarf. NLTE effects are taken into account, using a five-level atomic model for
LiI. Comparisons are presented with traditional 1D models having the same
effective temperature and gravity. The net result is that, while LTE results
differ dramatically between 1D and 2D models, especially in the metal-poor
case, this does not remain true when NLTE effects are included: 1D/2D
differences in the inferred NLTE Li abundance are always well below 0.1 dex.
The present computations still assume LTE in the continuum. New computations
removing this assumption are planned for the near future.

</DOC>
<DOC>
<DOCNO> 11718 </DOCNO>
Pairing evidence of 8CB molecules adsorbed on MoS2: Influence of 2D


  By combining X-ray diffraction studies under grazing incidence (GIXD) and
Scanning Tunneling Microscopy (STM) measurements, we have precisely determined
the structure of 8CB molecules adsorbed on MoS2, under the thick organic film.
The commensurability of the adsorbed network and the intracell structure have
been determined, revealing a complex structure characterized by a
non-equivalence of adjacent lamellae with pair associations of molecules in one
lamella over two. We have interpreted such a result by a simple model of a
single lamella. This pair association in one lamella over two appears as a
direct evidence of the connection between the commensurabilities in the two
directions. The value of the molecule-substrate potential corrugations is
particularly high, indicating that the dipolar momentum of 8CB molecules could
play a fundamental role in the molecule-substrate interactions

</DOC>
<DOC>
<DOCNO> 70849 </DOCNO>
pi-pi interaction amplitudes with chiral constraints


  The pi-pi interaction amplitudes have been calculated using a three coupled
channel model both with and without constraints imposed by chiral models. Roy's
equations have been used to compare the amplitudes and to study the role played
by chiral constraints in the pi-pi interaction.

</DOC>
<DOC>
<DOCNO> 119018 </DOCNO>
New Neighbors from 2MASS: Activity and Kinematics at the Bottom of the


  We have combined 2MASS and POSS II data in a search for nearby ultracool
(later than M6.5) dwarfs with K_s<12. Spectroscopic follow-up observations
identify 53 M7 to M9.5 dwarfs and seven L dwarfs. The observed space density is
0.0045 +- 0.0008 M8-M9.5 dwarfs per cubic parsec, without accounting for
biases, consistent with a mass function that is smooth across the
stellar/substellar limit. We show the observed frequency of H alpha emission
peaks at ~100% for M7 dwarfs and then decreases for cooler dwarfs. In absolute
terms, however, as measured by the ratio of H alpha to bolometric luminosity,
none of the ultracool M dwarfs can be considered very active compared to
earlier M dwarfs, and we show that the decrease that begins at spectral type M6
continues to the latest L dwarfs. We find that flaring is common among the
coolest M dwarfs and estimate the frequency of flares at 7% or higher. We show
that the kinematics of relatively active (EW_{H alpha}>6 Angstroms) ultracool M
dwarfs are consistent with an ordinary old disk stellar population, while the
kinematics of inactive ultracool M dwarfs are more typical of a 0.5 Gyr old
population. The early L dwarfs in the sample have kinematics consistent with
old ages, suggesting that the hydrogen burning limit is near spectral types
L2-L4. We use the available data on M and L dwarfs to show that chromospheric
activity drops with decreasing mass and temperature, and that at a given (M8 or
later) spectral type, the younger field (brown) dwarfs are less active than
many of the older, more massive field stellar dwarfs. Thus, contrary to the
well-known stellar age-activity relationship, low activity in field ultracool
dwarfs can be an indication of comparative youth and substellar mass.

</DOC>
<DOC>
<DOCNO> 83058 </DOCNO>
Compositionality, Synonymy, and the Systematic Representation of Meaning


  In a recent issue of Linguistics and Philosophy Kasmi and Pelletier (1998)
(K&P), and Westerstahl (1998) criticize Zadrozny's (1994) argument that any
semantics can be represented compositionally. The argument is based upon
Zadrozny's theorem that every meaning function m can be encoded by a function
\mu such that (i) for any expression E of a specified language L, m(E) can be
recovered from \mu(E), and (ii) \mu is a homomorphism from the syntactic
structures of L to interpretations of L.
   In both cases, the primary motivation for the objections brought against
Zadrozny's argument is the view that his encoding of the original meaning
function does not properly reflect the synonymy relations posited for the
language.
   In this paper, we argue that these technical criticisms do not go through.
In particular, we prove that \mu properly encodes synonymy relations, i.e. if
two expressions are synonymous, then their compositional meanings are
identical. This corrects some misconceptions about the function \mu, e.g.
Janssen (1997).
   We suggest that the reason that semanticists have been anxious to preserve
compositionality as a significant constraint on semantic theory is that it has
been mistakenly regarded as a condition that must be satisfied by any theory
that sustains a systematic connection between the meaning of an expression and
the meanings of its parts. Recent developments in formal and computational
semantics show that systematic theories of meanings need not be compositional.

</DOC>
<DOC>
<DOCNO> 13757 </DOCNO>
Colossal Magnetoresistant Materials: The Key Role of Phase Separation


  The study of the manganese oxides, widely known as manganites, that exhibit
the ``Colossal'' Magnetoresistance (CMR) effect is among the main areas of
research within the area of Strongly Correlated Electrons. After considerable
theoretical effort in recent years, mainly guided by computational and
mean-field studies of realistic models, considerable progress has been achieved
in understanding the curious properties of these compounds. These recent
studies suggest that the ground states of manganite models tend to be
intrinsically inhomogeneous due to the presence of strong tendencies toward
phase separation, typically involving ferromagnetic metallic and
antiferromagnetic charge and orbital ordered insulating domains. Calculations
of the resistivity versus temperature using mixed states lead to a good
agreement with experiments. The mixed-phase tendencies have two origins: (i)
electronic phase separation between phases with different densities that lead
to nanometer scale coexisting clusters, and (ii) disorder-induced phase
separation with percolative characteristics between equal-density phases,
driven by disorder near first-order metal-insulator transitions. The coexisting
clusters in the latter can be as large as a micrometer in size. It is argued
that a large variety of experiments reviewed in detail here contain results
compatible with the theoretical predictions. It is concluded that manganites
reveal such a wide variety of interesting physical phenomena that their
detailed study is quite important for progress in the field of Correlated
Electrons.

</DOC>
<DOC>
<DOCNO> 117234 </DOCNO>
Very promising hole in Bell's theorem


  Through the hole in Bell's theorem we can communicate with matter

</DOC>
<DOC>
<DOCNO> 84857 </DOCNO>
Kaluza-Klein Method in Theory of Rotating Quantum Fields


  Quantum fields on a stationary space-time in a rotating Killing reference
frame are considered. Finding solutions of wave equations in this frame is
reduced to a fiducial problem on a static background. The rotation results in a
gauge connection in a way similar to appearance of gauge fields in Kaluza-Klein
models. Such a Kaluza-Klein method in theory of rotating quantum fields enables
one to simplify computations and get a number of new results similar to those
established for static backgrounds. In particular, we find with its help
functional form of free energy at high temperatures. Applications of these
results to quantum fields near rotating black holes are briefly discussed.

</DOC>
<DOC>
<DOCNO> 68417 </DOCNO>
Seesaw model and its Lorentz group formulation


  For two flavors, the seesaw matrix can be identified with a two dimensional
representation of the Lorentz group. This analogy facilitates the computation
of physical neutrino parameters, while giving an intuitive understanding of the
results. It is found that the induced mixing angle exhibits resonance behavior.
For maximal mixing, we derive a precise relation among the right-handed mixing
angle, the Majorana mass ratio, and their phase.

</DOC>
<DOC>
<DOCNO> 69289 </DOCNO>
Twisted Family Structure and Neutrino Large Mixing


  I demonstrate that neutrino large mixing between $\nu_\mu$ and $\nu_\tau$ are
naturally reproduced using a novel mechanism called `E-twisting'in a
supersymmetric $E_6$ grand unification model. This model explains all the
characteristic features of the quark/lepton Dirac masses as well as the
neutrino's Majorana masses despite the fact that all the members in {\bf27} of
each generation are assigned a common family charge. Most remarkably, this
model yields a novel relation which gives the 2-3 lepton mixing angle
$\theta_{\mu\tau}$ in terms of quark masses and CKM mixing:
$\tan\theta_{\mu\tau}=(m_b/m_s)V_{cb}$, which is a kind of SO(10) GUT relation
similar to the celebrated SU(5) bottom-tau mass ratio. This relation is a
result of a common `twisted SO(10)' structure.+

</DOC>
<DOC>
<DOCNO> 84828 </DOCNO>
A first analysis regarding matter-dynamical diffeomorphism coupling


  A first attempt at adding matter degrees of freedom to the two-dimensional
``vacuum'' gravity model presented in gr-qc/9907071 is analyzed in this paper.
Just as in the previous pure gravity case, quantum diffeomorphism operators
(constructed from a Virasoro algebra) possess a dynamical content; their gauge
nature is recovered only after the classical limit. Emphasis is placed on the
new physical modes modelled on a SU(1,1)-Kac-Moody algebra. The non-trivial
coupling to ``gravity'' is a consequence of the natural semi-direct structure
of the entire extended algebra. A representation associated with the discrete
series of the rigid SU(1,1) is revisited in the light of previously neglected
crucial global features which imply the appearance of an SU(1,1)-Kac-Moody
fusion rule, determining the rather entangled quantum structure of the physical
system. In the classical limit, an action which explicitly couples gravity and
matter modes governs the dynamics.

</DOC>
<DOC>
<DOCNO> 11388 </DOCNO>
Random-bond Ising model in two dimensions, the Nishimori line, and


  We consider a classical random-bond Ising model (RBIM) with binary
distribution of $\pm K$ bonds on the square lattice at finite temperature. In
the phase diagram of this model there is the so-called Nishimori line which
intersects the phase boundary at a multicritical point. It is known that the
correlation functions obey many exact identities on this line. We use a
supersymmetry method to treat the disorder. In this approach the transfer
matrices of the model on the Nishimori line have an enhanced supersymmetry
osp($2n+1|2n$), in contrast to the rest of the phase diagram, where the
symmetry is osp($2n|2n$) (where $n$ is an arbitrary positive integer). An
anisotropic limit of the model leads to a one-dimensional quantum Hamiltonian
describing a chain of interacting superspins, which are irreducible
representations of the osp($2n+1|2n$) superalgebra. By generalizing this
superspin chain, we embed it into a wider class of models. These include other
models that have been studied previously in one and two dimensions. We suggest
that the multicritical behavior in two dimensions of a class of these
generalized models (possibly not including the multicritical point in the RBIM
itself) may be governed by a single fixed point, at which the supersymmetry is
enhanced still further to osp($2n+2|2n$). This suggestion is supported by a
calculation of the renormalization-group flows for the corresponding nonlinear
sigma models at weak coupling.

</DOC>
<DOC>
<DOCNO> 150694 </DOCNO>
Lumps and P-branes in Open String Field Theory


  We describe numerical methods for constructing lump solutions in open string
field theory. According to Sen, these lumps represent lower dimensional
Dp-Branes and numerical evaluation of their energy can be compared with the
expected value for the tension. We take particular care of all higher
derivative terms inherent in Witten's version of open string field theory. The
importance of these terms for off shell phenomena is argued in the text.
Detailed numerical calculations done for the case of general $p$ brane show
very good agreement with Sen's conjectured value. This gives credence to the
conjecture itself and establishes further the usefulness of Witten's version of
SFT .

</DOC>
<DOC>
<DOCNO> 85150 </DOCNO>
Time evolution in the presence of gravity


  We present a suggestion on the interpretation of canonical time evolution
when gravitation is present, based on the nonlinear gauge approach to gravity.
Essentially, our proposal consists of an internal-time concept, with the time
variable taken from the dynamical fields characteristic of the nonlinear
realization of the internal time-translational symmetry. Physical time
evolution requires the latter symmetry to be broken. After disregarding other
breaking mechanisms, we appeal to the Jordan-Brans-Dicke action, conveniently
interpreted, to achieve that goal. We show that nontrivial time evolution
follows, the special relativistic limit being recovered in the absence of
gravity.

</DOC>
<DOC>
<DOCNO> 71141 </DOCNO>
Gluon contribution to the structure function g_2(x,Q^2)


  We calculate the one-loop twist-3 gluon contribution to the flavor-singlet
structure function g_2(x,Q^2) in polarized deep-inelastic scattering and find
that it is dominated by the contribution of the three-gluon operator with the
lowest anomalous dimension (for each moment N). The similar property was
observed earlier for the nonsinglet distributions, although the reason is in
our case different. The result is encouraging and suggests a simple evolution
pattern of g_2(x,Q^2) in analogy with the conventional description of twist-2
parton distributions.

</DOC>
<DOC>
<DOCNO> 118394 </DOCNO>
ROSAT HRI monitoring of X-ray variability in the NLS1 galaxy PKS


  We present the results of ROSAT High Resolution Imager (HRI) observations and
the survey data of the radio-loud Narrow-Line Seyfert 1 galaxy (NLS1) PKS
0558--504. We find strong and persistent X-ray variability on both short and
medium time-scales. The most extreme amplitude variations require a radiative
efficiency exceeding the theoretical maximum for a Schwarzschild black hole,
suggesting the presence of a rotating black hole or the influence of
relativistic beaming effects. The spatial analysis rules out the possibility
that the high luminosity and the strong variability are related to a nearby
source.

</DOC>
<DOC>
<DOCNO> 151262 </DOCNO>
Geometry and the Low-Energy Theorem in N=1 Supersymmetric Theories


  We investigate geometrical structures and low-energy theorems of N=1
supersymmetric nonlinear sigma models in four dimensions. When a global
symmetry spontaneously breaks down to its subgroup, the low-energy effective
Lagrangian of massless particles is described by a supersymmetric nonlinear
sigma model whose target manifold is parametrized by Nambu-Goldstone (NG)
bosons and quasi-NG (QNG) bosons. The unbroken symmetry changes at each point
in the target manifold and some QNG bosons change to NG bosons when unbroken
symmetry become smaller. The QNG-NG change and their interpretation is shown in
a simple example, the O(N) model. We investigate low-energy theorems at general
points.

</DOC>
<DOC>
<DOCNO> 80860 </DOCNO>
Quark Loop Effects with an Improved Staggered Action


  We have been studying effects of dynamical quarks on various hadronic
observables, using our recently formulated improvement for staggered fermions.
To illustrate improvement, we show that the light hadron spectrum in the
quenched approximation gives remarkably good scaling. We highlight three new
results: (1) We find no apparent quark loop effects in the Edinburgh plot with
2+1 flavors of dynamical quarks at a = 0.14 fm. (2) We show that dynamical
quarks modify the shape of the heavy quark potential. (3) We present results
hinting at meson decay effects in light hadron spectroscopy.

</DOC>
<DOC>
<DOCNO> 68563 </DOCNO>
Mass bound of the lightest neutral Higgs scalar in the extra U(1) models


  The upper mass bound of the lightest neutral Higgs scalar is studied in the
$\mu$ problem solvable extra U(1) models by using the analysis of the
renormalization group equations. In order to restrict the parameter space we
take account of a condition of the radiative symmetry breaking and some
phenomenological constraints. We compare the bound obtained based on this
restricted parameter space with the one of the next to the minimal
supersymmetric standard model (NMSSM). Features of the scalar potential and
renormalization group equations of the Yukawa couplings among Higgs chiral
supermultiplets are rather different between them. They can reflect in this
bound.

</DOC>
<DOC>
<DOCNO> 152134 </DOCNO>
Generalized Coherent State Approach to Star Products and Applications to


  We construct a star product associated with an arbitrary two dimensional
Poisson structure using generalized coherent states on the complex plane. From
our approach one easily recovers the star product for the fuzzy torus, and also
one for the fuzzy sphere. For the latter we need to define the `fuzzy'
stereographic projection to the plane and the fuzzy sphere integration measure,
which in the commutative limit reduce to the usual formulae for the sphere.

</DOC>
<DOC>
<DOCNO> 170637 </DOCNO>
Optimal phase estimation and square root measurement


  We present an optimal strategy having finite outcomes for estimating a single
parameter of the displacement operator on an arbitrary finite dimensional
system using a finite number of identical samples. Assuming the uniform {\it a
priori} distribution for the displacement parameter, an optimal strategy can be
constructed by making the {\it square root measurement} based on uniformly
distributed sample points. This type of measurement automatically ensures the
global maximality of the figure of merit, that is, the so called average score
or fidelity. Quantum circuit implementations for the optimal strategies are
provided in the case of a two dimensional system.

</DOC>
<DOC>
<DOCNO> 70223 </DOCNO>
Virtual corrections to gg -> H to two loops in the heavy top limit


  The virtual corrections to the production cross section of a Standard Model
Higgs boson are computed up to order \alpha_s^4. Using an effective Lagrangian
for the limit M_t -> \infty, we evaluate the relevant massless two-loop vertex
diagrams by mapping them onto three-loop two-point functions, following a
method recently introduced by Baikov and Smirnov. As a result, we find a
gauge-invariant contribution to the total Higgs production cross section at
NNLO.

</DOC>
<DOC>
<DOCNO> 12228 </DOCNO>
ac Susceptibility in Granular Superconductors: Theory and Experiment


  A phenomenological theory to describe the electromagnetic properties of
granular superconductors, based on known bulk superconductors expressions and
conventional Josephson's junctions tunneling currents, is presented and
succesfully used to fit distinct experimental results for the magnetic
susceptibility as a function of the temperature and the applied magnetic field
of rather different samples.

</DOC>
<DOC>
<DOCNO> 67695 </DOCNO>
Thermal Field Theory in Equilibrium


  In this talk, I review recent developments in equilibrium thermal field
theory. Screened perturbation theory and hard-thermal-loop perturbation theory
are discussed. A self-consistent $\Phi$-derivable approach is also briefly
reviewed.

</DOC>
<DOC>
<DOCNO> 119774 </DOCNO>
Near-infrared adaptive optics observations of galaxy clusters: Abell 262


  We report on high angular resolution near-infrared (NIR) observations of
three galaxy clusters at different redshifts using adaptive optics (AO). In the
case of the barred spiral \object{UGC 1347} in Abell 262 we presented the first
AO results obtained using a laser guide star. The observations have been
carried out with the MPE/MPIA adaptive optics laser guide star system ALFA and
the ESO AO system ADONIS combined with the SHARP II+ camera built at MPE. The
three clusters are well suited for high resolution investigations since bright
field stars for tip-tilt or wavefront sensing are located close to the line of
sight to cluster galaxies. In summary our high angular resolution NIR data
combined with other information clearly indicates star formation activity or
interaction between cluster members at all three redshifts. The results and
implications for future high angular resolution adaptive optics observations
are discussed in the framework of current galaxy and cluster evolution models.

</DOC>
<DOC>
<DOCNO> 101914 </DOCNO>
Discrete approximations to integrals over unparametrized paths


  We discuss measures on spaces of unparametrized paths related to the Wiener
measure. These measures arise naturally in the study of one-dimensional gravity
coupled to scalar fields. Two kinds of discrete approximations are defined, the
piecewise linear and the hypercubic approximations. The convergence of these
approximations in the sense of weak convergence of measures is proven. We
describe a family of sets of unparametrized paths that are analogous to
cylinder sets of parametrized paths. Integrals over some of these sets are
evaluated in terms of Dirichlet propagators in bounded regions.

</DOC>
<DOC>
<DOCNO> 85477 </DOCNO>
Quantum Gravity at the Turn of the Millennium


  A very brief review is given of the current state of research in quantum
gravity. Over the past fifteen years, two approaches have emerged as the most
promising paths to a quantum theory of gravity: string theory and quantum
geometry. I will discuss the main achievements and open problems of each of
these approaches, and compare their strengths and weaknesses.

</DOC>
<DOC>
<DOCNO> 123283 </DOCNO>
Simulations of Incompressible MHD Turbulence


  We simulate incompressible MHD turbulence in the presence of a strong
background magnetic field. Our major conclusions are: 1) MHD turbulence is most
conveniently described in terms of counter propagating shear Alfven and slow
waves. Shear Alfven waves control the cascade dynamics. Slow waves play a
passive role and adopt the spectrum set by the shear Alfven waves, as does a
passive scalar. 2) MHD turbulence is anisotropic with energy cascading more
rapidly along k_perp than along k_parallel, where k_perp and k_parallel refer
to wavevector components perpendicular and parallel to the local magnetic
field. Anisotropy increases with increasing k_perp. 3) MHD turbulence is
generically strong in the sense that the waves which comprise it suffer order
unity distortions on timescales comparable to their periods. Nevertheless,
turbulent fluctuations are small deep inside the inertial range compared to the
background field. 4) Decaying MHD turbulence is unstable to an increase of the
imbalance between the flux of waves propagating in opposite directions along
the magnetic field. 5) Items 1-4 lend support to the model of strong MHD
turbulence by Goldreich & Sridhar (GS). Results from our simulations are also
consistent with the GS prediction gamma=2/3. The sole notable discrepancy is
that 1D power law spectra, E(k_perp) ~ k_perp^{-alpha}, determined from our
simulations exhibit alpha ~ 3/2, whereas the GS model predicts alpha = 5/3.

</DOC>
<DOC>
<DOCNO> 151287 </DOCNO>
Propagators for scalar bound states at finite temperature in a NJL model


  We reexamine physical causal propagators for scalar and pseudoscalar bound
states at finite temperature in a chiral $U_L(1)\times U_R(1)$ NJL model,
defined by four-point amputated functions subtracted through the gap equation,
and prove that they are completely equivalent in the imaginary-time and
real-time formalism by separating carefully the imaginary part of the
zero-temperature loop integral. It is shown that the thermal transformation
matrix of the matrix propagators for these bound states in the real-time
formalism is precisely the one of the matrix propagator for an elementary
scalar particle and this fact shows similarity of thermodynamic property
between a composite and an elementary scalar particle. The retarded and
advanced propagators for these bound states are also given explicitly from the
imaginary-time formalism.

</DOC>
<DOC>
<DOCNO> 8661 </DOCNO>
Ground state of excitons and charged excitons in a quantum well


  A variational calculation of the ground state of a neutral exciton and of
positively and negatively charged excitons (trions) in single quantum well is
presented. We study the dependance of the correlation energy and of the binding
energy on the well width and on the hole mass. Our results are are compared
with previous theoretical results and with avalaible experimental data.

</DOC>
<DOC>
<DOCNO> 121334 </DOCNO>
The Black Hole-Host Galaxy Relation in Active Galactic Nuclei


  The masses of the central black holes of Active Galactic Nuclei estimated by
the reverberation virial technique seem to be significantly smaller than
predicted from the black hole mass-bulge luminosity relation for massive black
holes detected by kinematic methods in less active and normal galaxies. We
reexamine the relation for updated data and suggest a few reasons that may
cause this discrepancy.

</DOC>
<DOC>
<DOCNO> 151540 </DOCNO>
Free Field Realization of D-brane in Group Manifold


  We construct the boundary state for the D-brane in the SU(2) group manifold
directly in terms of the group variables. We propose a matching condition for
the left- and the right-moving sectors including the zero modes that describes
a D-brane of the Neumann-type. The free field realization of the WZW model is
used to obtain the boundary state subject to the matching condition. We show
that the resulting state coincides with Cardy's state. The structure of the
BRST cohomology is realized by imposing the invariance of the state under the
Weyl group of the current algebra.

</DOC>
<DOC>
<DOCNO> 8207 </DOCNO>
Weak Charge Quantization as an Instanton of Interacting sigma-model


  Coulomb blockade in a quantum dot attached to a diffusive conductor is
considered in the framework of the non-linear sigma-model. It is shown that the
weak charge quantization on the dot is associated with instanton configurations
of the Q-field in the conductor. The instantons have a finite action and are
replica non--symmetric. It is argued that such instantons may play a role in
the transition regime to the interacting insulator.

</DOC>
<DOC>
<DOCNO> 121059 </DOCNO>
The X-ray Spectrum and Light Curve of Supernova 1995N


  We report on multi-epoch X-ray observations of the Type IIn (narrow emission
line) supernova SN 1995N with the ROSAT and ASCA satellites. The January 1998
ASCA X-ray spectrum is well fitted by a thermal bremsstrahlung (kT~10 keV,
N_H~6e20 cm^-2) or power-law (alpha~1.7, N_H~1e21 cm^-2) model. The X-ray light
curve shows evidence for significant flux evolution between August 1996 and
January 1998: the count rate from the source decreased by 30% between our
August 1996 and August 1997 ROSAT observations, and the X-ray luminosity most
likely increased by a factor of ~2 between our August 1997 ROSAT and January
1998 ASCA observations, although evolution of the spectral shape over this
interval is not ruled out. The high X-ray luminosity, L_X~1e41 erg/sec, places
SN 1995N in a small group of Type IIn supernovae with strong circumstellar
interaction, and the evolving X-ray luminosity suggests that the circumstellar
medium is distributed inhomogeneously.

</DOC>
<DOC>
<DOCNO> 9413 </DOCNO>
The Kalman-Levy filter


  The Kalman filter combines forecasts and new observations to obtain an
estimation which is optimal in the sense of a minimum average quadratic error.
The Kalman filter has two main restrictions: (i) the dynamical system is
assumed linear and (ii) forecasting errors and observational noises are taken
Gaussian. Here, we offer an important generalization to the case where errors
and noises have heavy tail distributions such as power laws and L\'evy laws.
The main tool needed to solve this ``Kalman-L\'evy'' filter is the
``tail-covariance'' matrix which generalizes the covariance matrix in the case
where it is mathematically ill-defined (i.e. for power law tail exponents $\mu
\leq 2$). We present the general solution and discuss its properties on
pedagogical examples. The standard Kalman-Gaussian filter is recovered for the
case $\mu = 2$. The optimal Kalman-L\'evy filter is found to deviate
substantially fro the standard Kalman-Gaussian filter as $\mu$ deviates from 2.
As $\mu$ decreases, novel observations are assimilated with less and less
weight as a small exponent $\mu$ implies large errors with significant
probabilities. In terms of implementation, the price-to-pay associated with the
presence of heavy tail noise distributions is that the standard linear
formalism valid for the Gaussian case is transformed into a nonlinear matrice
equation for the Kalman-L\'evy filter. Direct numerical experiments in the
univariate case confirms our theoretical predictions.

</DOC>
<DOC>
<DOCNO> 39681 </DOCNO>
CP violation in psi(2S) -> J/psi pi pi processes


  We propose to search for CP-violating effects in the decay
psi(2S)->J/psi+pi+pi. The scheme has the advantage that one does not need to
track two or more CP-conjugate processes. Model independent amplitudes are
derived for this purpose. The fact that leading CP violating terms are O(k)
under low energy expansion and the processes are flavor disconnected make the
measurement of these CP breaking parameters practical. Our results can be
extended to the case of Upsilon(2S)->Upsilon(1S)+pi+pi and
Upsilon(3S)->Upsilon(2S)+pi+pi straightforwardly.

</DOC>
<DOC>
<DOCNO> 12198 </DOCNO>
Empirical properties of the variety of a financial portfolio and the


  We investigate the variety of a portfolio of stocks in normal and extreme
days of market activity. We show that the variety carries information about the
market activity which is not present in the single-index model and we observe
that the variety time evolution is not time reversal around the crash days. We
obtain the theoretical relation between the square variety and the mean return
of the ensemble return distribution predicted by the single-index model. The
single-index model is able to mimic the average behavior of the square variety
but fails in describing quantitatively the relation between the square variety
and the mean return of the ensemble distribution. The difference between
empirical data and theoretical description is more pronounced for large
positive values of the mean return of the ensemble distribution. Other
significant deviations are also observed for extreme negative values of the
mean return.

</DOC>
<DOC>
<DOCNO> 68201 </DOCNO>
CP Violation and Quark Mixing


  Measurements of CP asymmetries in B decays will soon be made at $B$ factories
and hadron machines. In light of this, we review and update the profile of the
CKM unitarity triangle and the resulting CP asymmetries in B decays. This is
done both in the standard model and in several variants of the minimal
supersymmetric standard model (MSSM), which are characterized by a single phase
in the quark flavour mixing matrix. After imposing present constraints on the
parameters of these models, the predicted ranges of $\sin 2 \beta$ in the
standard model and in the MSSM are found to be similar. However, these theories
may be distinguished by future precise measurements of the other two
CP-violating phases $\alpha$ and $\gamma$.

</DOC>
<DOC>
<DOCNO> 150777 </DOCNO>
BRST Invariance and Renormalisability of the SU(2)$\times$U(1)


  Since the SU(n) gauge theory with massive gauge bosons has been proven to be
renormalisable we reinvestigate the renormalisability of the
 SU$_L$(2) $\times$ U$_Y$(1) electroweak theory with massive W Z bosons. We
expound that with the constraint conditions caused by the W Z mass term and the
additional condition chosen by us we can performed the quantization and
construct the ghost action in a way similar to that used for the massive SU(n)
theory. We also show that when the $\delta-$ functions appearing in the path
integral of the Green functions and representing the constraint conditions are
rewritten as Fourier integrals with Lagrange multipliers $\lambda_a$ and
$\lambda_y$, the BRST invariance is kept in the total effective action
consisting of the Lagrange multipliers, ghost fields and the original fields.
Furthermore, by comparing with the massless theory and with the massive SU(n)
theory we find the general form of the divergent part of the generating
functional for the regular vertex functions and prove the renormalisability of
the theory. It is also clarified that the renormalisability of the theory with
the W Z mass term is ensured by that of the massless theory and the massive
SU(n) theory.

</DOC>
<DOC>
<DOCNO> 118339 </DOCNO>
Spatially resolved Spectro-photometry of M81: Age, Metallicity and


  In this paper, we present a multi-color photometric study of the nearby
spiral galaxy M81, using images obtained with the Beijing Astronomical
Observatory 60/90 cm Schmidt Telescope in 13 intermediate-band filters from
3800 to 10000{\AA}. The observations cover the whole area of M81 with a total
integration of 51 hours from February 1995 to February 1997. This provides a
multi-color map of M81 in pixels of $1\arcsec.7 \times 1\arcsec.7$. Using
theoretical stellar population synthesis models, we demonstrate that some BATC
colors and color indices can be used to disentangle the age and metallicity
effect. We compare in detail the observed properties of M81 with the
predictions from population synthesis models and quantify the relative chemical
abundance, age and reddening distributions for different components of M81. We
find that the metallicity of M81 is about $Z=0.03$ with no significant
difference over the whole galaxy. In contrast, an age gradient is found between
stellar populations of the central regions and of the bulge and disk regions of
M81: the stellar population in its central regions is older than 8 Gyr while
the disk stars are considerably younger, $\sim 2$ Gyr. We also give the
reddening distribution in M81. Some dust lanes are found in the galaxy bulge
region and the reddening in the outer disk is higher than that in the central
regions.

</DOC>
<DOC>
<DOCNO> 68998 </DOCNO>
Electromagnetic form factors of nucleons and Delta*


  A relativistic quark model and a new set of wave functions of nucleon and
Delta have been used to study the electromagnetic propertities of (1/2)^+
baryons and photoelectric production of Delta(1236).

</DOC>
<DOC>
<DOCNO> 13512 </DOCNO>
Statistical Mechanics of the Vicinal Surfaces with Adsorption


  We study the vicinal surface with adsorption below the roughening
temperature, using the restricted solid-on-solid model coupled with the Ising
model. By the product-wavefunction renormalization group method, we calculate
the surface gradient $p$ and the adsorption coverage $\Theta$ as a function of
the Andreev field $\eta$ which makes surface tilt. Combining Monte Carlo
calculations, we show that there emerges effective attraction between the
steps. This attractive interaction leads to instability against step bunching.

</DOC>
<DOC>
<DOCNO> 67720 </DOCNO>
Outstanding problems in the phenomenology of hard diffractive scattering


  This paper is a summary of the discussion within the Diffractive and Low-x
Physics Working Group at the 1999 Durham Collider Workshop of the
interpretation of the Tevatron and HERA measurements of inclusive hard
diffraction.

</DOC>
<DOC>
<DOCNO> 119032 </DOCNO>
Strange stars - linear approximation of the EOS and maximum QPO


  The equation of state of strange matter build of the u,d,s quarks in the
framework of the MIT bag model is studied. The scaling relations with bag
constant are discussed and applied to the determination of maximum frequency of
a particle in stable circular orbit around strange star. The highest QPO
frequency of 1.33 kHz observed so far is consistent with the strange stars
models for which the maximum QPO frequency is 1.7-2.4 kHz depending on the
strange quark mass and the QCD coupling constant. The linear approximation of
the equation of state is found and the parameters of this EOS are determined as
a functions of strange quark mass, QCD coupling constant and bag constant. This
approximation reproduces exact results within an error of the order of 1% and
can be used for the complete study of the properties of strange stars including
microscopic stability of strange matter and determination of the total baryon
number of the star.

</DOC>
<DOC>
<DOCNO> 178938 </DOCNO>
Asymmetric nuclear matter in a Hartree-Fock approach to non-linear QHD


  The Equation of State (EOS) for asymmetric nuclear matter is discussed
starting from a phenomenological hadronic field theory of Serot-Walecka type
including exchange terms. In a model with self interactions of the scalar
sigma-meson we show that the Fock terms naturally lead to isospin effects in
the nuclear EOS. These effects are quite large and dominate over the
contribution due to isovector mesons. We obtain a potential symmetry term of
"stiff" type, i.e. increasing with baryon density and an interesting behaviour
of neutron/proton effective masses of relevance for transport properties of
asymmetric dense matter.

</DOC>
<DOC>
<DOCNO> 9583 </DOCNO>
Cooper pair dispersion relation in two dimensions


  The Cooper pair binding energy {\it vs.} center-of-mass-momentum dispersion
relation for Bose-Einstein condensation studies of superconductivity is found
in two dimensions for a renormalized attractive delta interaction. It crosses
over smoothly from a linear to a quadratic form as coupling varies from weak to
strong.

</DOC>
<DOC>
<DOCNO> 101891 </DOCNO>
Bosons in a Trap: Asymptotic Exactness of the Gross-Pitaevskii Ground


  Recent experimental breakthroughs in the treatment of dilute Bose gases have
renewed interest in their quantum mechanical description, respectively in
approximations to it. The ground state properties of dilute Bose gases confined
in external potentials and interacting via repulsive short range forces are
usually described by means of the Gross-Pitaevskii energy functional. In joint
work with Elliott H. Lieb and Jakob Yngvason its status as an approximation for
the quantum mechanical many-body ground state problem has recently been
rigorously clarified. We present a summary of this work, for both the two- and
three-dimensional case.

</DOC>
<DOC>
<DOCNO> 12535 </DOCNO>
Fermi-Liquid Theory for Anisotropic Superconductors


  This article develops a Fermi-liquid theory for superconductors with
anisotropic Fermi surfaces, Fermi-liquid interactions, and energy gaps. For
d-wave superconductors, the Fermi-liquid interaction effects are found to be
classifiable into strong and negligible renormalizaton effects, for symmetric
and antisymmetric combinations of the energies of $k\uparrow$ and
$-k\downarrow$ quasiparticles, respectively. Furthermore, the leading
clean-limit temperature-dependent correction to the superfluid density in a
d-wave superconductor is found to be renormalized by a Fermi velocity (or mass)
renormalization effect. The question is raised of whether or not the
penetration depth in the high temperature superconductor
YBa$_2$Cu$_3$O$_{6+x}a$ can be accounted for with physically acceptable
parameters within the framework of a quasiparticle model. Fermi-liquid
corrections to the spin susceptibility and to the zero-energy
magnetic-field-induced density of states are also evaluated.

</DOC>
<DOC>
<DOCNO> 101983 </DOCNO>
On the uniqueness conjecture for Markoff triples


  This paper has been withdrawn by author due to an error in the proof.

</DOC>
<DOC>
<DOCNO> 11468 </DOCNO>
Correlated hopping of electrons: Effect on the Brinkman-Rice transition


  We study the Hubbard model with bond-charge interaction (`correlated
hopping') in terms of the Gutzwiller wave function. We show how to express the
Gutzwiller expectation value of the bond-charge interaction in terms of the
correlated momentum-space occupation. This relation is valid in all spatial
dimensions. We find that in infinite dimensions, where the Gutzwiller
approximation becomes exact, the bond-charge interaction lowers the critical
Hubbard interaction for the Brinkman-Rice metal-insulator transition. The
bond-charge interaction also favors ferromagnetic transitions, especially if
the density of states is not symmetric and has a large spectral weight below
the Fermi energy.

</DOC>
<DOC>
<DOCNO> 118449 </DOCNO>
Galactic Worm 123.4-1.5: A Mushroom-shaped HI Cloud


  The Dominion Radio Astrophysical Observatory's Synthesis Telescope provides
the highest resolution data (1 arcmin and 0.82 km/s) to date of an HI worm
candidate. Observed as part of the Canadian Galactic Plane Survey,
mushroom-shaped GW 123.4-1.5 extends only a few hundred parsecs, contains ~10^5
solar masses of neutral hydrogen, and appears unrelated to a conventional shell
or chimney structure. Our preliminary Zeus-2d models use a single off-plane
explosion with a modest (~10^{51} ergs) energy input. These generic simulations
generate, interior to an expanding outer blast wave, a buoyant cloud whose
structure resembles the morphology of the observed feature. Unlike typical
model superbubbles, the stem can be narrow because its width is not governed by
the pressure behind the blast wave nor the disk scale height. Using this type
of approach it should be possible to more accurately model the thin stem and
other details of GW 123.4-1.5 in the future.

</DOC>
<DOC>
<DOCNO> 10585 </DOCNO>
Local off-cubic distortion the cause for the low- and high-spin states


  It is pointed out that it is the local symmetry that determines the
realization of the low- and high-spin state of the Co3+ ion. We can rigorously
prove it treating the Co3+ ion as the highly-correlated electron system 3d6,
that fulfiles the Hund's rules with taking into account the spin-orbit
coupling. As the function of the sign of the off-cubic crystal-field distortion
the magnetic or non-magnetic state is realized.

</DOC>
<DOC>
<DOCNO> 71086 </DOCNO>
Experimental status of pionium at CERN


  The DIRAC Collaboration presents a first search for "atomic pi(+) pi(-)
pairs" from ionization of pionium.

</DOC>
<DOC>
<DOCNO> 83336 </DOCNO>
More accurate tests for the statistical significance of result


  Statistical significance testing of differences in values of metrics like
recall, precision and balanced F-score is a necessary part of empirical natural
language processing. Unfortunately, we find in a set of experiments that many
commonly used tests often underestimate the significance and so are less likely
to detect differences that exist between different techniques. This
underestimation comes from an independence assumption that is often violated.
We point out some useful tests that do not make this assumption, including
computationally-intensive randomization tests.

</DOC>
<DOC>
<DOCNO> 99355 </DOCNO>
Logarithmic Jet Bundles and Applications


  We generalize Demailly's construction of projective jet bundles and strictly
negatively curved pseudometrics on them to the logarithmic case. We establish
this logarithmic generalization explicitly via coordinates, just as Noguchi's
generalization of the jets used by Green-Griffiths. As a first application, we
give a metric proof for the logarithmic version of Lang's conjecture concerning
the hyperbolicity of complements of divisors in a semi-abelian variety as well
as for the corresponding big Picard theorem.

</DOC>
<DOC>
<DOCNO> 12446 </DOCNO>
Resonances, instabilities, and structure selection of driven Josephson


  We investigate dynamics of Josephson vortex lattice in layered high T$_{c}$
superconductors at high magnetic fields. It is shown that the average electric
current depends on the lattice structure and is resonantly enhanced when the
Josephson frequency matches the frequency of the plasma mode. We find the
stability regions of moving lattice. It is shown that a specific lattice
structure at given velocity is uniquely selected by the boundary conditions: at
small velocities periodic triangular lattice is stable and looses its stability
at some critical velocity. At even higher velocities a structure close to a
rectangular lattice is restored.

</DOC>
<DOC>
<DOCNO> 151030 </DOCNO>
The M-theory dual of a 3 dimensional theory with reduced supersymmetry


  In a recent paper, Polchinski and Strassler found a string theory dual of a
gauge theory with reduced supersymmetry. Motivated by their approach, we
perturb the $\N=8$ theory living on a set of N M2 branes to $\N=2$, by adding
fermion mass terms. We obtain M-theory duals corresponding to M2 branes
polarized into M5 branes, in $AdS_4 \times S_7$. In the course of doing this we
come across an interesting feature of the M5 brane action, which we comment on.
Depending on the fermion masses we obtain discrete or continuous vacua for our
theories. We also obtain dual descriptions for domain walls, instantons and
condensates.

</DOC>
<DOC>
<DOCNO> 99941 </DOCNO>
Comparison between Geometric Quantisation and Covariant Quantum


  We compare the covariant formulation of Quantum Mechanics on a curved
spacetime fibred on absolute time with the standard Geometric Quantisation.

</DOC>
<DOC>
<DOCNO> 119915 </DOCNO>
Quantifying Morphological Evolution from Low to High Redshifts


  Establishing the morphological history of ordinary galaxies was one of the
original goals for the Hubble Space Telescope, and remarkable progress toward
achieving this this goal has been made. How much of this progress has been at
the expense of the Hubble sequence? As we probe further out in redshift space,
it seems time to re-examine the underlying significance of Hubble's tuning fork
in light of the the spectacular and often bizarre morphological characteristics
of high redshift galaxies. The aim of this review is to build a morphological
bridge between high-redshift and low-redshift galaxy populations, by using
quantitative morphological measures to determine the maximum redshift for which
the Hubble sequence provides a meaningful description of the galaxy population.
I will outline the various techniques used to quantify high-redshift galaxy
morphology, highlight the aspects of the Hubble sequence being probed by these
techniques, and indicate what is getting left behind. I will argue that at
higher redshifts new techniques (and new ideas) that place less emphasis on
classical morphology and more emphasis on the link between morphology and
resolved stellar populations are needed in order to probe the evolutionary
history of high-redshift galaxies.

</DOC>
<DOC>
<DOCNO> 71917 </DOCNO>
Open Charm Enhancement in Pb+Pb Collisions at SPS


  The statistical coalescence model for the production of open and hidden charm
is considered within the canonical ensemble formulation. The data for the
J/\psi multiplicity in Pb+Pb collisions at 158 A GeV are used for the model
prediction of the open charm yield. We find a strong enhancement of the open
charm production, by a factor of about 2--4, over the standard hard-collision
model extrapolation from nucleon-nucleon to nucleus-nucleus collisions. A
possible mechanism of the open charm enhancement in A+A collisions at the SPS
energies is proposed.

</DOC>
<DOC>
<DOCNO> 123069 </DOCNO>
Accretion discs models with the "beta"-viscosity prescription derived


  We examine under which conditions one may apply, to steady state keplerian
accretion discs, the "beta"-viscosity prescription which has been derived from
rotating shear flow experiments (Richard & Zahn 1999). Using a vertically
averaged model, we show that this law may be suitable for all three families of
known systems: in young stellar objects, evolved binary stars and Active
Galactic Nuclei discs (except in their outer gas pressure dominated regions
where turbulence becomes hypersonic). According to the standard criterion for
viscous stability, "beta"-discs are always stable throughout. Using realistic
opacities and equation of state, we demonstrate that these discs are thermally
unstable in the temperature domain where hydrogen recombines, when they are
optically thick, and this could lead to limit cycle behavior. Radiation
pressure dominated regions are thermally stable, in contrast with
"alpha"-discs. This results in a fully stable solution for the innermost parts
of AGN discs.

</DOC>
<DOC>
<DOCNO> 99368 </DOCNO>
Functional self-similarity and renormalization group symmetry in


  The result from developing and applying the notions of functional
self-similarity and the Bogoliubov renormalization group to boundary-value
problems in mathematical physics during the last decade are reviewed. The main
achievement is the regular algorithm for finding renormalization group-type
symmetries using the contemporary theory of Lie groups of transformations.

</DOC>
<DOC>
<DOCNO> 121032 </DOCNO>
On Solar System and Cosmic Rays Nucleosynthesis and Spallation Processes


  A brief survey of nuclide abundances in the solar-system and in cosmic rays
and of the believed mechanisms of their synthesis is given. The role of
spallation processes in nucleosynthesis is discussed. A short review of recent
measurements, compilations, calculations, and evaluations of spallation cross
sections relevant to nuclear astrophysics is given as well. It is shown that in
some past astrophysical simulations, old experimental nuclear data and
theoretical cross sections that are in poor agreement with recent measurements
and calculations were used. New astrophysical simulations using recently
measured and reliably calculated nuclear cross sections, further researches in
obtaining better cross sections, and production of evaluated spallation cross
sections libraries for astrophysics are suggested.

</DOC>
<DOC>
<DOCNO> 39689 </DOCNO>
Search for the Decay B0 -> D*0 gamma


  We report results of a search for the rare radiative decay B0 -> D*0 gamma.
Using 9.7 million BB meson pairs collected with the CLEO detector at the
Cornell Electron Storage Ring, we limit Br(B0->D*0 gamma) < 5.0 * 10^-5 at 90%
CL. This provides evidence that anomalous enhancement is absent in W-exchange
processes and that weak radiative B decays are dominated by the short-distance
b -> s gamma mechanism in the Standard Model.

</DOC>
<DOC>
<DOCNO> 68709 </DOCNO>
A Two Parameter Texture of Nearly Bi-maximal Neutrino Mixing


  We propose a texture of three generation Majorana-type neutrino mass matrix
in terms of only two parameters which gives rise to nearly bi-maximal mixing
angles. We also demonstrate an explicit realization of such type of neutrino
mass-matrix in the context of an $SU(2)_L$$\times$$U(1)_Y$ model due to higher
dimensional mass terms through the inclusion of discrete $Z_3$$\times$$Z_4$
symmetry and two extra singlet Higgs fields.

</DOC>
<DOC>
<DOCNO> 101090 </DOCNO>
Some conjectures about the Hilbert series of generic ideals in the


  We give conjectures on the "asymptotic" behaviour of the Hilbert series of
(quotients by) generic ideals in the exterior algebra, as the number of
variables tend to infinity. Our conjectures are supported by extensive computer
calculations.

</DOC>
<DOC>
<DOCNO> 151101 </DOCNO>
Singular Instantons Made Regular


  The singularity present in cosmological instantons of the Hawking-Turok type
is resolved by a conformal transformation, where the conformal factor has a
linear zero of codimension one. We show that if the underlying regular manifold
is taken to have the topology of $RP^4$, and the conformal factor is taken to
be a twisted field so that the zero is enforced, then one obtains a
one-parameter family of solutions of the classical field equations, where the
minimal action solution has the conformal zero located on a minimal volume
noncontractible $RP^3$ submanifold. For instantons with two singularities, the
corresponding topology is that of a cylinder $S^3\times [0,1]$ with D=4
analogues of `cross-caps' at each of the endpoints.

</DOC>
<DOC>
<DOCNO> 85426 </DOCNO>
3+1 spinfoam model of quantum gravity with spacelike and timelike


  We present a spinfoam formulation of Lorentzian quantum General Relativity.
The theory is based on a simple generalization of an Euclidean model defined in
terms of a field theory over a group. The model is an extension of a recently
introduced Lorentzian model, in which both timelike and spacelike components
are included. The spinfoams in the model, corresponding to quantized
4-geometries, carry a natural non-perturbative local causal structure induced
by the geometry of the algebra of the internal gauge (sl(2,C)). Amplitudes can
be expressed as integrals over the spacelike unit-vectors hyperboloid in
Minkowski space, or the imaginary Lobachevskian space.

</DOC>
<DOC>
<DOCNO> 118803 </DOCNO>
Stochastic Fluctuations in the Spectrophotometric Properties of Star


  Integrated spectrophotometric properties of stellar systems are intrinsically
dispersed due to the stochastic nature of the small numbers of bright stars
they contain. Among clusters, only the most massive ones can be used
individually for comparison with the mean properties predicted by population
synthesis calculations. The appropriate minimal masses depend, among others, on
the waveband or colour index studied and on age. Selected indices (near-IR CO
and H2O, EW(Halpha)) are used to illustrate the asymmetric nature of the
probability distribution of observable properties and their dependence on
cluster mass.

</DOC>
<DOC>
<DOCNO> 152471 </DOCNO>
Some Comments on Branes, G-flux, and K-theory


  This is a summary of a talk at Strings2000 explaining three ways in which
string theory and M-theory are related to the mathematics of K-theory.

</DOC>
<DOC>
<DOCNO> 169607 </DOCNO>
Covariance, correlation and entanglement


  Some new identities for quantum variance and covariance involving commutators
are presented, in which the density matrix and the operators are treated
symmetrically. A measure of entanglement is proposed for bipartite systems,
based on covariance. This works for two- and three-component systems but
produces ambiguities for multicomponent systems of composite dimension. Its
relationship to angular momentum dispersion for symmetric symmetric spin states
is described.

</DOC>
<DOC>
<DOCNO> 70546 </DOCNO>
Single Charged Higgs production as a probe of CP violation at a Muon


  We consider single charged Higgs ($H^{\pm}$) production in association with a
$W^{\pm}$ boson at $\mu^+\mu^-$ colliders, in the context of the general CP
violating Two Higgs Doublet Model (2HDM). We find that large cross-sections for
the processes $\mu^+\mu^-\to H^+W^-,H^-W^+$ are possible, and offer an
attractive way of producing $H^{\pm}$ at $\mu^+\mu^-$ colliders. The difference
in the cross-sections for $H^+W^-$ and $H^-W^+$ may exceed 1000 fb, and this
represents a novel way of probing CP violation in the Higgs sector.

</DOC>
<DOC>
<DOCNO> 71776 </DOCNO>
Allowable Low-Energy E_6 Subgroups from Leptogenesis


  There are only two viable low-energy $E_6$ subgroups: $SU(3)_C \times SU(2)_L
\times U(1)_Y \times U(1)_N$ or $SU(3)_C \times SU(2)_L \times SU(2)'_R \times
U(1)_{Y_L + Y'_R}$, which would not erase any preexisting lepton asymmetry of
the Universe that may have been created by the decay of heavy singlet
(right-handed) neutrinos or any other mechanism. They are also the two most
favored $E_6$ subgroups from a recent analysis of present neutral-current data.
We study details of the leptogenesis, as well as some salient experimental
signatures of the two models.

</DOC>
<DOC>
<DOCNO> 8861 </DOCNO>
Dislocation scattering in a two-dimensional electron gas


  A theory of scattering by charged dislocation lines in a two-dimensional
electron gas (2DEG) is developed. The theory is directed towards understanding
transport in AlGaN/GaN high-electron-mobility transistors (HEMT), which have a
large number of line dislocations piercing through the 2DEG. The scattering
time due to dislocations is derived for a 2DEG in closed form. This work
identifies dislocation scattering as a mobility-limiting scattering mechanism
in 2DEGs with high dislocation densities. The insensitivity of the 2DEG (as
compared to bulk) to dislocation scattering is explained by the theory.

</DOC>
<DOC>
<DOCNO> 40436 </DOCNO>
Double Tag Events in Two-Photon Collisions at LEP


  Double tag events in two photon collisions are studied using the L3 detector
at the LEP center of mass energies $\sqrt{s} \simeq 189-202$ GeV. The
cross-section of $\gamma ^* \gamma ^*$ collisions is measured at an average
photon virtuality $<Q^2 > = 15 \rm{GeV}^2$. The results are in agreement with
Monte Carlo predictions based on perturbative QCD, while the Quark Parton Model
alone is insufficient to describe the data. The measurements are compared to
the LO and the NLO BFKL calculations

</DOC>
<DOC>
<DOCNO> 170462 </DOCNO>
Three-qubit pure-state canonical forms


  In this paper we analyze the canonical forms into which any pure three-qubit
state can be cast. The minimal forms, i.e. the ones with the minimal number of
product states built from local bases, are also presented and lead to a
complete classification of pure three-qubit states. This classification is
related to the values of the polynomial invariants under local unitary
transformations by a one-to-one correspondence.

</DOC>
<DOC>
<DOCNO> 121550 </DOCNO>
Ionized Gas in Damped Lyman Alpha Protogalaxies: II. Comparison Between


  We test semi-analytic models for galaxy formation with accurate kinematic
data of damped Lyman alpha protogalaxies (DLAs) presented in the companion
paper I. The models envisage centrifugally supported exponential disks at the
centers of dark matter halos which are filled with ionized gas undergoing
radial infall to the disks. The halo masses are drawn from cross-section
weighted mass distributions predicted by CDM cosmogonies, or by the null
hypothesis (TF model) that the dark matter mass distribution has not evolved
since z ~ 3. In our models, C IV absorption lines detected in DLAs arise in
infalling ionized clouds while the low-ion absorption lines arise from neutral
gas in the disks. Using Monte Carlo methods we find: (a) The CDM models are
incompatible with the low-ion statistics at more than 99% confidence whereas
some TF models cannot be excluded at more than 88% confidence. (b) Both CDM and
TF models agree with the observed distribution of C IV velocity widths. (c) The
CDM models generate differences between the mean velocities of C IV and low ion
profiles in agreement with the data, while the TF model produces differences in
the means that are too large. (d) Both CDM and TF models produce ratios of C IV
to low-ion velocity widths that are too large. (e) Both CDM and TF models
generate C IV versus low-ion cross-correlation functions incompatible with the
data.
  While it is possible to select model parameters resulting in consistency with
the data, the disk-halo configuration assumed in both cosmogonies still does
not produce significant overlap in velocity space between C IV low-ion velocity
profiles. We conjecture that including angular momentum of the infalling clouds
will increase the overlap between C IV and low-ion profiles.

</DOC>
<DOC>
<DOCNO> 9883 </DOCNO>
A scalar model of inhomogeneous elastic and granular media


  We investigate theoretically how the stress propagation characteristics of
granular materials evolve as they are subjected to increasing pressures,
comparing the results of a two-dimensional scalar lattice model to those of a
molecular dynamics simulation of slightly polydisperse discs.
  We characterize the statistical properties of the forces using the force
histogram and a two-point spatial correlation function of the forces. For the
lattice model, in the granular limit the force histogram has an exponential
tail at large forces, while in the elastic regime the force histogram is much
narrower and has a form that depends on the realization of disorder in the
model. The behavior of the force histogram in the molecular dynamics
simulations as the pressure is increased is very similar to that displayed by
the lattice model. In contrast, the spatial correlations evolve qualitatively
differently in the lattice model and in the molecular dynamics simulations. For
the lattice model, in the granular limit there are no in-plane stress-stress
correlations, whereas in the molecular dynamics simulation significant in-plane
correlations persist to the lowest pressures studied.

</DOC>
<DOC>
<DOCNO> 121951 </DOCNO>
Faint Scattering Around Pulsars: Probing the Interstellar Medium on


  We have made high-resolution, high-sensitivity dynamic spectra of a sample of
strong pulsars at 430 MHz with the Arecibo radiotelescope. For 4 pulsars we
find faint but sharply delineated features in the secondary spectra. These are
examples of the previously observed ``crisscross'' or ``multiple drift slope''
phenomenon presumed to be due to multiple imaging of the pulsar by the
interstellar medium. The unprecedented resolution and dynamic range of our
observations allow a deeper level of analysis. Distances to the dominant
scattering screen along the line of sight are determined and are shown to agree
well with those inferred from other scintillation phenomena. Multiple imaging
of the pulsar by the ISM is required. A compact central image surrounded by a
faint scattering halo, roughly circularly symmetric, is consistent with the
data. Scattering from filaments may also be consistent. The angular extent of
the scattering material parallel to the direction of the pulsar velocity is
roughly 5 mas, corresponding to a linear extent of about 2 AU. Further
observations of these features should allow better discrimination between
models and an identification of the scattering structures.

</DOC>
<DOC>
<DOCNO> 101248 </DOCNO>
Examples of one-parameter automorphism groups of UHF algebras


  Examples of (strongly continuous) one-parameter groups of automorphisms of
UHF C*-algebras are given. One example has the property that the infinitesimal
generator does not have a union of finite-dimensional subalgebras as a core.
(This solves the so-called core problem, raised by S. Sakai, in the negative.)
The other has the property of not being classical or commutative, i.e., the
one-parameter group is not just an inner perturbation of a one-parameter group
which has an increasing sequence of invariant finite-dimensional subalgebras
with dense union. (This was certainly expected but has not been proven
explicitly.)

</DOC>
<DOC>
<DOCNO> 170079 </DOCNO>
Preferred Frame versus Multisimultaneity: meaning and relevance of a


  It is argued that: 1) Quantum Mechanics implies the preferred frame also
because of the collapse delayed at detection, 2) forthcoming experiments with
moving beam-splitters will allow us to decide between Preferred Frame and
Multisimultaneity, and 3) if the Preferred Frame prevails, superluminal
communication is in principle possible.

</DOC>
<DOC>
<DOCNO> 102502 </DOCNO>
Composition of points and Mordell-Weil problem for cubic surfaces


  Let $V$ be a plane smooth cubic curve over a finitely generated field $k.$
The Mordell-Weil theorem for $V$ states that there is a finite subset
$P\subset V(k)$ such that the whole $V(k)$ can be obtained from $P$ by drawing
secants and tangents through pairs of previously constructed points and
consecutively adding their new intersection points with $V.$ Equivalently, the
group of birational transformations of $V$ generated by reflections with
respect to $k$-points is finitely generated. In this paper, elaborating an
idea from [M3], we establish a Mordell-Weil type finite generation result for
some birationally trivial cubic surfaces $W$. To the contrary, we prove that
the birational automorphism group generated by reflections cannot be finitely
generated if $W(k)$ is infinite.

</DOC>
<DOC>
<DOCNO> 84117 </DOCNO>
Boson Stars: Alternatives to primordial black holes?


  The present surge for the astrophysical relevance of boson stars stems from
the speculative possibility that these compact objects could provide a
considerable fraction of the non-baryonic part of dark matter within the halo
of galaxies. For a very light `universal' axion of effective string models,
their total gravitational mass will be in the most likely range of \sim 0.5
M_\odot of MACHOs. According to this framework, gravitational microlensing is
indirectly ``weighing" the axion mass, resulting in \sim 10^{-10} eV/c^2. This
conclusion is not changing much, if we use a dilaton type self-interaction for
the bosons. Moreover, we review their formation, rotation and stability as
likely candidates of astrophysical importance.

</DOC>
<DOC>
<DOCNO> 116605 </DOCNO>
An orbital-free molecular dynamics study of melting in K_20, K_55, K_92,


  The melting-like transition in potasium clusters K_N, with N=20, 55, 92 and
142, is studied by using an orbital-free density-functional constant-energy
molecular dynamics simulation method, and compared to previous theoretical
results on the melting-like transition in sodium clusters of the same sizes.
Melting in potasium and sodium clusters proceeds in a similar way: a surface
melting stage develops upon heating before the homogeneous melting temperature
is reached. Premelting effects are nevertheless more important and more easily
established in potasium clusters, and the transition regions spread over
temperature intervals which are wider than in the case of sodium. For all the
sizes considered, the percentage melting temperature reduction when passing
from Na to K clusters is substantially larger than in the bulk. Once those two
materials have been compared for a number of different cluster sizes, we study
the melting-like transition in Rb_55 and Cs_55 clusters and make a comparison
with the melting behavior of Na_55 and K_55. As the atomic number increases,
the height of the specific heat peaks decreases, their width increases, and the
melting temperature decreases as in bulk melting, but in a more pronounced way.

</DOC>
<DOC>
<DOCNO> 120357 </DOCNO>
Formation of an Infalling Disklike Envelope around a Protostar


  We examined the gravitational contraction of isothermal molecular cloud cores
with slow rotation by means of two-dimensional numerical simulations. Applying
a sink-cell method, we followed the evolution of the cloud cores up to the
stages at which most of the matter accretes onto the central region (i.e., a
protostar and a rotationally-supported circumstellar disk). We show that both
an infalling disklike envelope and a rotationally-supported disk around the
central star are natural outcome of the gravitational contraction of a {\it
prolate} cloud core with slow rotation. The early evolution of the infalling
envelopes resembles sheet models recently proposed by Hartmann and coworkers.
In the infalling disklike envelope, the radial profiles of the density, radial
velocity, and azimuthal velocity can be approximated by $\rho\propto r^{-1.5}$,
$v_r\propto r^{-0.5}$, and $v_\phi\propto r^{-1}$, respectively. The fate of
the infalling envelopes is also discussed.

</DOC>
<DOC>
<DOCNO> 10039 </DOCNO>
The dynamics of the spherical p-spin model: from microscopic to


  We have numerically investigated the mean-field dynamics of the the $p$-spin
interaction spin glass model with p=3 using an efficient method of integrating
the dynamic equations. We find a new time scale associated with the onset of
the breakdown of the fluctuation-dissipation theorem in the intermediate time
regime. We also find that the off-equilibrium relaxation exhibits a sub-aging
behavior in the intermediate times and crosses over to a simple aging in the
asymptotic regime.

</DOC>
<DOC>
<DOCNO> 100758 </DOCNO>
On universal minimal compact G-spaces


  For every topological group G one can define the universal minimal compact
G-space X=M_G characterized by the following properties: (1) X has no proper
closed G-invariant subsets; (2) for every compact G-space Y there exists a
G-map X-->Y. If G is the group of all orientation-preserving homeomorphisms of
the circle S^1, then M_G can be identified with S^1 (V. Pestov). We show that
the circle cannot be replaced by the Hilbert cube or a compact manifold of
dimension >1. This answers a question of V. Pestov. Moreover, we prove that for
every topological group G the action of G on M_G is not 3-transitive.

</DOC>
<DOC>
<DOCNO> 102614 </DOCNO>
Einstein Metrics Adapted to Contact Structures on 3-Manifolds


  The Newman-Penrose-Perjes formalism is applied to smooth contact structures
on riemannian 3-manifolds. In particular it is shown that a contact 3-manifold
admits an adapted riemannian metric if and only if it admits a metric with a
divergence-free, constantly twisting, geodesic congruence. The shear of this
congruence is identified with the torsion of the associated pseudohermitian
structure, while the Tanaka-Webster curvature is identified with certain
derivatives of the spin coefficients. The particular case where the associated
riemannian metric is Einstein is studied in detail. It is found that the
torsion is constant and the field equations are completely solved locally.
Hyperbolic space forms are shown not to have adapted contact structures, even
locally, while contact structures adapted to a flat or elliptic space form are
contact isometric to the standard one.

</DOC>
<DOC>
<DOCNO> 101590 </DOCNO>
Chern characters via connections up to homotopy


  The aim of this note is to point out that Chern characters can be computed
using curvatures o ``super-connections up to homotopy'. We also present an
application to the vanishing theorem for Lie algebroids which is at the origin
of new secondary classes of algebroids (Fernandes), hence, in particular, of
Poisson manifolds.

</DOC>
<DOC>
<DOCNO> 70820 </DOCNO>
Brans-Dicke brane cosmology


  A five dimensional brane cosmology with non-minimally coupled scalar field to
gravity has been considered in a Jordan-Brans-Dicke frame. We derive an
effective four dimensional field equations on a 3+1 dimensional brane where the
fifth dimension has been assumed to have an orbifold symmetry. We have noticed
that the evolution equation for the matter component stuck to the brane is
non-trivially coupled to the scalar field living on the brane and the bulk.
Finally we discuss some cosmological consequences of this set-up.

</DOC>
<DOC>
<DOCNO> 152345 </DOCNO>
The evolution of unstable black holes in anti-de Sitter space


  We examine the thermodynamic stability of large black holes in
four-dimensional anti-de Sitter space, and we demonstrate numerically that
black holes which lack local thermodynamic stability often also lack stability
against small perturbations. This shows that no-hair theorems do not apply in
anti-de Sitter space. A heuristic argument, based on thermodynamics only,
suggests that if there are any violations of Cosmic Censorship in the evolution
of unstable black holes in anti-de Sitter space, they are beyond the reach of a
perturbative analysis.

</DOC>
<DOC>
<DOCNO> 40462 </DOCNO>
CP-violating ZZh Coupling at e+e- Linear Colliders


  We study the general Higgs-weak boson coupling with CP-violation via the
process e+e- -> f \bar f h. We categorize the signal channels by sub-processes
Zh production and ZZ fusion and construct four CP asymmetries by exploiting
polarized e+e- beams. We find complementarity among the sub-processes and the
asymmetries to probe the real and imaginary parts of the CP-violating form
factor. Certain asymmetries with unpolarized beams can retain significant
sensitivity to the coupling. We conclude that at a linear collider with high
luminosity, the CP-odd ZZh coupling may be sensitively probed via measurements
of the asymmetries.

</DOC>
<DOC>
<DOCNO> 151985 </DOCNO>
Hidden symmetries of supersymmetric p-form gauge theories


  Field theories with p-form gauge potentials can possess ``hidden'' symmetries
leaving the field strengths invariant on-shell without being gauge symmetries
on-shell. The relevance of such symmetries to supersymmetric models is
discussed. They provide central charges of supersymmetry algebras, play a
particular role in duality relations, and lead to peculiar interactions. A
multiplet of N=2 supersymmetry in four dimensions with two hidden central
charges is presented.

</DOC>
<DOC>
<DOCNO> 121299 </DOCNO>
Substructure and halo density profiles in a Warm Dark Matter scenario


  High-resolution cosmological N-body simulations were performed in order to
study the substructure of Milky Way-like galactic halos and the density
profiles of halos in a warm dark matter scenario. The results favor this
scenario with respect to the cold dark matter one.

</DOC>
<DOC>
<DOCNO> 69447 </DOCNO>
On the Inclusive Determination of V_{ub} from the Lepton Invariant Mass


  Bauer, Ligeti and Luke have recently proposed a new method for measuring
|V_{ub}| in inclusive semileptonic B decays, using a cut on the lepton
invariant mass to discriminate against b->c transitions. We investigate the
structure of the heavy-quark expansion for this case and show that to all
orders the magnitude of the leading perturbative and nonperturbative
corrections is controlled by a hadronic scale mu_c=O(m_c) depending on the
minimal value of q^2. These corrections can be analyzed using a modified
version of the heavy-quark expansion (``hybrid expansion''). We find that the
theoretical uncertainty in the extraction of |V_{ub}| is a factor 2.5 larger
than previously estimated, which allows for a determination with 10% accuracy.

</DOC>
<DOC>
<DOCNO> 71964 </DOCNO>
Branching ratios and CP-violating asymmetries of $B_s \to h_1 h_2 $


  Based on the low-energy effective Hamiltonian with the generalized
factorization, we calculate the new physics contributions to branching ratios
and CP-violating asymmetries of the charmless hadronic decays $B_s \to h_1 h_2$
in the standard model and the general two-Higgs doublet models (models I, II,
and III). Within the considered paramter space, we find the following. (a) In
models I and II, the new physics corrections are always small in size and will
be masked by other larger known theoretical uncertainties. (b) In model III,
the new physics corrections to the branching ratios of those QCD
penguin-dominated decays $\ov B_s \to K^0\etapp, K^+ K^{-*}, etc.$, are large
in size and insensitive to the variations of $\mhp$ and $\nceff$. For tree- or
electroweak penguin-dominated decay modes, however, the new physics corrections
are very small in size. (c) For $\ov B_s \to K^+ K^{-*}$ and other seven decay
modes, the branching ratios are at the level of $(1-3)\times 10^{-5}$ and will
be measurable at the future hadron colliders with large $b$ production. (d)
Among the studied thirty nine $B_s$ meson decay modes, seven of them can have a
CP-violating asymmetry ${\cal A}_{CP}$ larger than 20% in magnitude. The new
physics corrections are small or moderate in magnitude. (e) Because of its
large and $\nceff$ stable branching ratio and CP violating asymmetry, the decay
$\ov B_s \to K^+ K^{-*}$ seems to be the "best" channel to find CP violation of
$B_s$ system through studies of two-body charmless decays of $B_s$ meson.

</DOC>
<DOC>
<DOCNO> 118564 </DOCNO>
Detection and Mapping of Decoupled Stellar and Ionized Gas Structures in


  Integral field optical spectroscopy with the INTEGRAL fiber-fed system and
HST optical imaging are used to map the complex stellar and warm ionized gas
structure in the ultraluminous infrared galaxy IRAS 12112+0305. Images
reconstructed from wavelength-delimited extractions of the integral field
spectra reveal that the observed ionized gas distribution is decoupled from the
stellar main body of the galaxy, with the dominant continuum and emission-line
regions separated by projected distances of up to 7.5 kpc. The two optical
nuclei are detected as apparently faint emission-line regions, and their
optical properties are consistent with being dust-enshrouded weak-[OI] LINERs.
The brightest emission-line region is associated with a faint (m_{I}= 20.4),
giant HII region of 600 pc diameter, where a young (about 5 Myr) massive
cluster of about 2 $\times$ 10$^7$ $M_{\odot}$ dominates the ionization.
Internal reddening towards the line-emitting regions and the optical nuclei
ranges from 1 to 8 magnitudes, in the visual. Taken the reddening into aacount,
the overall star formation in IRAS 12112+0305 is dominated by starbursts
associated with the two nuclei and corresponding to a star formation rate of 80
$M_{\odot}$ yr$^{-1}$.

</DOC>
<DOC>
<DOCNO> 9524 </DOCNO>
Optical Studies of a Layered Manganite La_{1.2}Sr_{1.8}Mn_2O_7 : Polaron


  Optical conductivity spectra of a cleaved ab-plane of a
La_{1.2}Sr_{1.8}Mn_2O_7 single crystal exhibit a small polaron absorption band
in the mid-infrared region at overall temperatures. With decreasing temperature
(T) to Curie temperature (T_C), the center frequency of the small polaron band
moves to a higher frequency, resulting in a gap-like feature, and that it
collapses to a lower frequency below T_C. Interestingly, with decreasing T, the
stretching phonon mode hardens above T_C and softens below T_C. These
concurring changes of lattice and electronic structure indicate that short
range polaron correlation exist above T_C but disappear with a magnetic
ordering.

</DOC>
<DOC>
<DOCNO> 118485 </DOCNO>
Power law burst and inter-burst interval distributions in the solar


  We calculate for the first time the probability density functions (PDFs) P of
burst energy e, duration T and inter-burst interval tau for a known turbulent
system in nature. Bursts in the earth-sun component of the Poynting flux at 1
AU in the solar wind were measured using the MFI and SWE experiments on the
NASA WIND spacecraft. We find P(e) and P(T) to be power laws, consistent with
self-organised criticality (SOC). We find also a power law form for P(tau) that
distinguishes this turbulent cascade from the exponential P(tau) of ideal SOC,
but not from some other SOC-like sandpile models. We discuss the implications
for the relation between SOC and turbulence.

</DOC>
<DOC>
<DOCNO> 39814 </DOCNO>
Hybrid Meson Structure at COMPASS


  We describe a pion physics program attainable with the CERN COMPASS
spectrometer, involving tracking detectors and an electromagnetic calorimeter.
COMPASS can realize state-of-the-art pion beam hybrid meson and meson radiative
transition studies. We review here the physics motivation for this program. We
describe the beam, detector, trigger requirements, and hardware/software
requirements for this program. The triggers for all this hybrid meson physics
can be implemented for simultaneous data taking.
  We will investigate hybrid meson production via pion-photon Primakoff and
pion-Pomeron diffractive interactions. We will determine new properties of
quark-antiquark-gluon hybrid mesons, using unique production methods, to
improve our understanding of these exotic mesons.
  The CERN COMPASS experiment uses 100-280 GeV beams (muon, pion), and magnetic
spectrometers and calorimeters, to measure the complete kinematics of
pion-photon and pion-Pomeron reactions. The COMPASS experiment is currently
under construction, and scheduled to begin data runs in 2001. We carry out
simulation studies to optimize the beam, detector, trigger, and
hardware/software for achieving high statistics data with low systematic
uncertainties in the hybrid meson component of this program. We will improve
previous Primakoff Hybrid studies by three orders of magnitude. We implement
special detectors and triggers for hybrid meson production reactions. We
propose to prepare for these COMPASS pion beam hybrid studies by setting up
with muon beam tests.

</DOC>
<DOC>
<DOCNO> 101793 </DOCNO>
Idempotent functional analysis: an algebraic approach


  In this paper we consider Idempotent Functional Analysis, an `abstract'
version of Idempotent Analysis developed by V. P. Maslov and his collaborators.
We give a review of the basic ideas of Idempotent Analysis. The correspondence
between concepts and theorems of the traditional Functional Analysis and its
idempotent version is discussed; this correspondence is similar to N. Bohr's
correspondence principle in quantum theory.
  We present an algebraical approach to Idempotent Functional Analysis. Basic
notions and results are formulated in algebraical terms; the essential point is
that the operation of idempotent addition can be defined for arbitrary infinite
sets of summands. We study idempotent analogs of the main theorems of linear
functional analysis and results concerning the general form of a linear
functional and scalar products in idempotent spaces.

</DOC>
<DOC>
<DOCNO> 99683 </DOCNO>
On cotriangular Hopf algebras


  In 1997 we proved that any triangular semisimple Hopf algebra over an
algebraically closed field k of characteristic 0 is obtained from the group
algebra k[G] of a finite group G, by twisting its comultiplication by a twist
in the sense of Drinfeld. In this paper, we generalize this result to not
necessarily finite-dimensional cotriangular Hopf algebras. Namely, our main
result says that a cotriangular Hopf algebra A over k is obtained from a
function algebra of a pro-algebraic group by twisting by a Hopf 2-cocycle, and
possibly changing its R-form by a central grouplike element of A^* of order
<=2, IF AND ONLY IF the trace of squared antipode on any finite-dimensional
subcoalgebra of A is the dimension of this subcoalgebra. This generalization,
like the original theorem, is proved using Deligne's theorem on Tannakian
categories.
  In the second half of the paper, we give examples of twisted function
algebras. In particular, we show that in the infinite- dimensional case, the
squared antipode may not equal the identity. On the other hand, we show that in
all of our examples of twisted function algebras, the squared antipode is
unipotent, and conjecture it to be the case for any twisted function algebra.
We prove this conjecture in a large number of special cases, using the
quantization theory of the first author and D.Kazhdan.

</DOC>
<DOC>
<DOCNO> 69958 </DOCNO>
Out of equilibrium O (N) linear-sigma system - Construction of


  We establish from first principles a perturbative framework that allows us to
compute reaction rates for processes taking place in nonequilibrium $O (N)$
linear-sigma systems in broken phase. The system of our concern is quasiuniform
system near equilibrium or nonequilibrium quasistationary system. We employ the
closed-time-path formalism and use the so-called gradient approximation. No
further approximation is introduced. In the course of construction of the
framework, we obtain the gap equation that determines the effective masses of
$\pi$ and of $\sigma$, and the generalized Boltzmann equation that describes
the evolution of the number-density functions of $\pi$ and of $\sigma$.

</DOC>
<DOC>
<DOCNO> 118516 </DOCNO>
Michelson Interferometry with the Keck I Telescope


  We report the first use of Michelson interferometry on the Keck I telescope
for diffraction-limited imaging in the near infrared JHK and L bands. By using
an aperture mask located close to the f/25 secondary, the 10 m Keck primary
mirror was transformed into a separate-element, multiple aperture
interferometer. This has allowed diffraction-limited imaging of a large number
of bright astrophysical targets, including the geometrically complex dust
envelopes around a number of evolved stars. The successful restoration of these
images, with dynamic ranges in excess of 200:1, highlights the significant
capabilities of sparse aperture imaging as compared with more conventional
filled-pupil speckle imaging for the class of bright targets considered here.
In particular the enhancement of the signal-to-noise ratio of the Fourier data,
precipitated by the reduction in atmospheric noise, allows high fidelity
imaging of complex sources with small numbers of short-exposure images relative
to speckle. Multi-epoch measurements confirm the reliability of this imaging
technique and our whole dataset provides a powerful demonstration of the
capabilities of aperture masking methods when utilized with the current
generation of large-aperture telescopes. The relationship between these new
results and recent advances in interferometry and adaptive optics is briefly
discussed.

</DOC>
<DOC>
<DOCNO> 170051 </DOCNO>
More on Optical Holonomic Quantum Computer


  We in this paper consider a further generalization of the (optical) holonomic
quantum computation proposed by Zanardi and Rasetti (quant-ph/9904011), and
reinforced by Fujii (quant-ph/9910069) and Pachos and Chountasis
(quant-ph/9912093). We construct a quantum computational bundle on some
parameter space, and calculate non-abelian Berry connections and curvatures
explicitly in the special cases. Our main tool is unitary coherent operators
based on Lie algebras su(n+1) and su(n,1), where the case of n = 1 is the
previous one.

</DOC>
<DOC>
<DOCNO> 84761 </DOCNO>
On the concept of mass point in general relativity


  The correct characterization of the concept of mass point in general
relativity is a straightforward consequence of the original form of solution
given by Schwarzschild to the problem of the Einstein field of a material
point.

</DOC>
<DOC>
<DOCNO> 85147 </DOCNO>
Third Quantization of Brans-Dicke Cosmology


  We study the third quantization of a Brans-Dicke toy model, we calculate the
number density of the universes created from nothing and found that it has a
Planckian form. Also, we calculated the uncertainty relation for this model by
means of functional Schr"odinger equation and we found that fluctuations of the
third-quantized universe field tends to a finite limit in the course of cosmic
expansion.

</DOC>
<DOC>
<DOCNO> 101896 </DOCNO>
Semi-classical motion of dressed electrons


  We consider an electron coupled to the quantized radiation field and subject
to a slowly varying electrostatic potential. We establish that over
sufficiently long times radiation effects are negligible and the dressed
electron is governed by an effective one-particle Hamiltonian. In the proof
only a few generic properties of the full Pauli-Fierz Hamiltonian H_PF enter.
Most importantly, H_PF must have an isolated ground state band for |p| < p_c <=
\infty with p the total momentum and p_c indicating that the ground state band
may terminate. This structure demands a local approximation theorem, in the
sense that the one- particle approximation holds until the semi-classical
dynamics violates |p|<p_c. Within this framework we prove an abstract Hilbert
space theorem which uses no additional information on the Hamiltonian away from
the band of interest. Our result is applicable to other time-dependent
semi-classical problems. We discuss semi-classical distributions for the
effective one-particle dynamics and show how they can be translated to the full
dynamics by our results.

</DOC>
<DOC>
<DOCNO> 84108 </DOCNO>
Fock representations from U(1) holonomy algebras


  We revisit the quantization of U(1) holonomy algebras using the abelian C*
algebra based techniques which form the mathematical underpinnings of current
efforts to construct loop quantum gravity. In particular, we clarify the role
of ``smeared loops'' and of Poincare invariance in the construction of Fock
representations of these algebras. This enables us to critically re-examine
early pioneering efforts to construct Fock space representations of linearised
gravity and free Maxwell theory from holonomy algebras through an application
of the (then current) techniques of loop quantum gravity.

</DOC>
<DOC>
<DOCNO> 116822 </DOCNO>
Ienversionless gain in an optically-dense resonant Doppler-broadened


  Resonant nonlinear-optical interference processes in four-level
Doppler-broadened media are studied. Specific features of amplification and
optical switching of short-wavelength radiation in a strongly-absorbing
resonant gas under coherent quantum control with two longer wavelength
radiations, are investigated. The major outcomes are illustrated with virtual
experiments aimed at inversionless short-wavelength amplification, which also
address deficiencies in this regard in recent experiments. With numerical
simulations related to the proposed experiment in optically-dense sodium dimer
vapor, we show optimal condition for optical switching and the expected gain of
the probe radiation, which is above the oscillation threshold.

</DOC>
<DOC>
<DOCNO> 84389 </DOCNO>
Fermat-holonomic congruences


  Fermat-holonomic congruences are proposed as a weaker substitute for the too
restrictive class of Born-rigid motions. The definition is expressed as a set
of differential equations. Integrability conditions and Cauchy data are
studied.

</DOC>
<DOC>
<DOCNO> 9047 </DOCNO>
The Numerical Renormalization Group Method for correlated electrons


  The Numerical Renormalization Group method (NRG) has been developed by Wilson
in the 1970's to investigate the Kondo problem. The NRG allows the
non-perturbative calculation of static and dynamic properties for a variety of
impurity models. In addition, this method has been recently generalized to
lattice models within the Dynamical Mean Field Theory. This paper gives a brief
historical overview of the development of the NRG and discusses its application
to the Hubbard model; in particular the results for the Mott metal-insulator
transition at low temperatures.

</DOC>
<DOC>
<DOCNO> 11579 </DOCNO>
"Lifshitz tails" and extended states in an Imaginary random potential


  Non-Hermitean operators may appear during the calculation of a partition
function in various models of statistical mechanics. The tail eigen-states,
having anomalously small real part of energy $Re(\eps)$, became naturally
important in this case. We consider the distribution of such states and the
form of eigenfunctions for the particle propagating in an imaginary random
potential (the model motivated by the statistics of polymer chains). Unlike it
is in the Hermitean quantum mechanics, our tail states are sufficiently
extended. Such state appear if the values of random potential turns out to be
anomalously close inside the large area. Results of numerical simulations in
the case of strong coupling confirm the analytic estimates.

</DOC>
<DOC>
<DOCNO> 70306 </DOCNO>
Neutrino Oscillation and CP Violation


  We reconsider the meaning of observing CP violation in neutrino oscillation.

</DOC>
<DOC>
<DOCNO> 151790 </DOCNO>
Large N field theories from superstrings


  These are introductory lectures on the correspondence between SU(N) gauge
theories and Superstring Theory in anti-de Sitter geometries (AdS). The subject
combines a number of different topics, including supersymmetric field theory,
classical and quantum physics of black holes, string theory, string dualities,
conformal field theories (CFT), and quantum field theory in anti-de Sitter
spaces. We also discuss applications of this AdS/CFT correspondence to the
large $N$ dynamics of pure QCD.

</DOC>
<DOC>
<DOCNO> 68218 </DOCNO>
Finite width effects and gauge cancellations in W- and Z-boson


  The processes of production and subsequent decay of W- and Z-bosons in $e^+
e^-$ collisions are considered in a recently proposed modified perturbation
theory (PT), based on a direct expansion of probabilities instead of
amplitudes. In such an approach the non-integrable singularities in the phase
space, which are intrinsic in the conventional PT, appear as singularities in
the coupling constant (with subsequent compensation by the decay factors of
unstable particles). In the present paper the systematic investigation of the
modified PT is carried out. The results are compared with the results of the
conventional approach, based on calculation of the amplitude with Dyson
resummation. A solution to the problem of the loss of one-loop PT order in the
resonance region is found. On the basis of this solution the proof of gauge
cancellations in any order of the modified PT is given. A simple generalization
of the fermion-loop scheme is proposed which provides a complete description of
W-pair production in next-to-leading order approximation.

</DOC>
<DOC>
<DOCNO> 69557 </DOCNO>
D-particle Recoil Space Times and "Glueball" Masses


  We discuss the properties of matter in a D-dimensional anti-de-Sitter-type
space time induced dynamically by the recoil of a very heavy
D(irichlet)-particle defect embedded in it. The particular form of the recoil
geometry, which from a world-sheet view point follows from logarithmic
conformal field theory deformations of the pertinent sigma-models, results in
the presence of both infrared and ultraviolet (spatial) cut-offs. These are
crucial in ensuring the presence of mass gaps in scalar matter propagating in
the D-particle recoil space time. The analogy of this problem with the
Liouville-string approach to QCD, suggested earlier by John Ellis and one of
the present authors, prompts us to identify the resulting scalar masses with
those obtained in the supergravity approach based on the Maldacena's
conjecture, but without the imposition of any supersymmetry in our case. Within
reasonable numerical uncertainties, we observe that agreement is obtained
between the two approaches for a particular value of the ratio of the two
cut-offs of the recoil geometry. Notably, our approach does not suffer from the
ambiguities of the supergravity approach as regards the validity of the
comparison of the glueball masses computed there with those obtained in the
continuum limit of lattice gauge theories.

</DOC>
<DOC>
<DOCNO> 69529 </DOCNO>
A unique large thermal source of real and virtual photons in the


  The data of direct single-photon measurements of the WA98 collaboration in
the reaction Pb(158 AGeV) + Pb are analyzed within a thermal model with a
minimum number of parameters adjusted to the dilepton data obtained by the
CERES and NA50 collaborations in the reactions Pb(158 AGeV) + Au, Pb. The
agreement of our model with the WA98 data points to a unique large thermal
source emitting electromagnetic radiation observable in both the real and
virtual photon channels.

</DOC>
<DOC>
<DOCNO> 122624 </DOCNO>
The Dyer-Roeder distance in quintessence cosmology and the estimation of


  We calculate analytically and numerically the Dyer-Roeder distance in perfect
fluid quintessence models and give an accurate fit to the numerical solutions
for all the values of the density parameter and the quintessence equation of
state. Then we apply our solutions to the estimation of $H_{0}$ from multiple
image time delays and find that the inclusion of quintessence modifies sensibly
the likelihood distribution of $H_{0}$, generally reducing the best estimate
with respect to a pure cosmological constant. Marginalizing over the other
parameters ($\Omega_{m}$ and the quintessence equation of state), we obtain
$H_{0}=71\pm 6$ km/sec/Mpc for an empty beam and $H_{0}=64\pm 4$ km/sec/Mpc for
a filled beam. We also discuss the future prospects for distinguishing
quintessence from a cosmological constant with time delays.

</DOC>
<DOC>
<DOCNO> 121937 </DOCNO>
Does the Mass Accretion Rate Depend On the Radius of the Accreting Star?


  In some circumstances, the mass accretion rate M^dot onto a compact star may
depend not only on external boundary conditions, but also on the radius R of
the star. Writing the dependence as a power-law in which M^dot is proportional
to R^p, we estimate the power-law index, p, for transient binary systems in a
quiescent state. We use the observed luminosities $L$ of accreting neutron
stars (R=10^6 cm) in soft X-ray transients and white dwarfs (R=10^9 cm) in
similar cataclysmic variables, and estimate M^dot in each system through the
relation L=(GM/R)*M^dot, where M is the mass of the star. From the available
data we infer that p~0.9+-0.5. This radial dependence is consistent with
radiatively inefficient accretion flows that either are convective or lose mass
via a wind.

</DOC>
<DOC>
<DOCNO> 99548 </DOCNO>
Naturality and Induced Representations


  We show that induction of covariant representations for C*-dynamical systems
is natural in the sense that it gives a natural transformation between certain
crossed-product functors. This involves setting up suitable categories of
C*-algebras and dynamical systems, and extending the usual constructions of
crossed products to define the appropriate functors. From this point of view,
Green's Imprimitivity Theorem identifies the functors for which induction is a
natural equivalence. Various spcecial cases of these results have previously
been obtained on an ad hoc basis.

</DOC>
<DOC>
<DOCNO> 85382 </DOCNO>
Status of Microscopic Modeling of Black Holes by D1-D5 System


  We briefly review the microscopic modeling of black holes as bound states of
branes in the context of the soluble D1-D5 system. We present a discussion of
the low energy brane dynamics and account for black hole thermodynamics and
Hawking radiation rates. These considerations are valid in the regime of
supergravity due to the non-renormalization of the low energy dynamics in this
model. Using Maldacena duality and standard statistical mechanics methods one
can account for black hole thermodynamics and calculate the absorption cross
section and the Hawking radiation rates. Hence, at least in the case of this
model black hole, since we can account for black hole properties within a
unitary theory, there is no information paradox.

</DOC>
<DOC>
<DOCNO> 99957 </DOCNO>
Linearization of analytic and non--analytic germs of diffeomorphisms of


  We study Siegel's center problem on the linearization of germs of
diffeomorphisms in one variable. In addition of the classical problems of
formal and analytic linearization, we give sufficient conditions for the
linearization to belong to some algebras of ultradifferentiable germs closed
under composition and derivation, including Gevrey classes.
  In the analytic case we give a positive answer to a question of J.-C. Yoccoz
on the optimality of the estimates obtained by the classical majorant series
method.
  In the ultradifferentiable case we prove that the Brjuno condition is
sufficient for the linearization to belong to the same class of the germ. If
one allows the linearization to be less regular than the germ one finds new
arithmetical conditions, weaker than the Brjuno condition. We briefly discuss
the optimality of our results.

</DOC>
<DOC>
<DOCNO> 12193 </DOCNO>
Quantized Vorticity in Superfluid 3He-A


  Superfluid 3He-A displays the largest variety in vortex structure among the
presently known coherent quantum systems. The experimentally verified
information comes mostly from NMR measurements on the rotating fluid, from
which the order-parameter texture can often be worked out. The various vortex
structures differ in the topology of their order-parameter field, in energy,
critical velocity, and in their response to temporal variations in the
externally applied flow. They require different experimental conditions for
their creation. When the flow is applied in the superfluid state, the structure
with the lowest critical velocity is formed. In 3He-A this leads to the various
forms of continuous (or singularity-free) vorticity. Which particular structure
is created depends on the externally applied conditions and on the global
order-parameter texture.

</DOC>
<DOC>
<DOCNO> 72224 </DOCNO>
Quark Orbital Angular Momentum in the Baryon


  Analytical and numerical results, for the orbital and spin content carried by
different quark flavors in the baryons, are given in the chiral quark model
with symmetry breaking. The reduction of the quark spin, due to the spin
dilution in the chiral splitting processes, is transferred into the orbital
motion of quarks and antiquarks. The orbital angular momentum for each quark
flavor in the proton as a function of the partition factor $\kappa$ and the
chiral splitting probability $a$ is shown. The cancellation between the spin
and orbital contributions in the spin sum rule and in the baryon magnetic
moments is discussed.

</DOC>
<DOC>
<DOCNO> 9310 </DOCNO>
Micro-canonical Statistical Mechanics of some Non-Extensive Systems


  Non-extensive systems do not allow to go to the thermodynamic limit.
  Therefore we have to reformulate statistical mechanics without invoking the
thermodynamical limit. I.e. we have to go back to Pre-Gibbsian times. We show
that Boltzmann's mechanical definition of entropy S as function of the
conserved ``extensive'' variables energy E, particle number N etc. allows to
describe even the most sophisticated cases of phase transitions unambiguously
for ``small'' systems like nuclei, atomic clusters, and selfgravitating
astrophysical systems: The rich topology of the curvature of S(E,N) shows the
whole ``Zoo'' of transitions: transitions of 1.order including the surface
tension at phase-separation, continuous transitions, critical and
multi-critical points. The transitions are the ``catastrophes'' of the Laplace
transform from the ``extensive'' to the ``intensive'' variables. Moreover, this
classification of phase transitions is much more natural than the Yang-Lee
criterion.

</DOC>
<DOC>
<DOCNO> 116376 </DOCNO>
Auroral field-aligned currents by incoherent scatter plasma line


  The aim of the Swedish-Japanese EISCAT campaign in February 1999 was to
measure the ionospheric parameters inside and outside the auroral arcs. The ion
line radar experiment was optimised to probe the E-region and lower F-region
with as high a speed as possible. Two extra channels were used for the plasma
line measurements covering the same altitudes, giving a total of 3 upshifted
and 3 downshifted frequency bands of 25 kHz each. For most of the time the
shifted channels were tuned to 3 (both), 4 (up), 5.5 (down) and 6.5 (both) MHz.
Weak signals are seen whenever the radar is probing the diffuse aurora,
corresponding to the relatively low plasma frequencies. At times when auroral
arcs pass the radar beam, significant increases in return power are observed.
Many cases with simultaneously up and down shifted plasma lines are recorded.
In spite of the rather active environment, the highly optimised measurements
enable investigation of the properties of the plasma lines. A modified
theoretical incoherent scatter spectrum is used to explain the measurements.
The general trend is an upgoing field-aligned current in the diffuse aurora,
confirmed with a full fit of the combined ion and plasma line spectra. There
are also cases with strong suprathermal currents indicated by large differences
in signal strength between up- and downshifted plasma lines.

</DOC>
<DOC>
<DOCNO> 122873 </DOCNO>
The cepheid-like relationship between variability and luminosity


  I show how an empirical variability - luminosity relationship for prompt
gamma-ray bursts, first proposed by Fenimore and Ramirez-Ruiz, can be
understood as a special-relativistic beaming effect in the ``cannonball model''
of Dar and De R\'ujula. In this scenario the variability is a measure of the
direction of propagation and the Lorentz factor of the cannonball on which in
turn the apparent luminosity of the prompt GRB depends sensitively. The
observed absence of cosmological time dilation in the ``aligned peak test'' -
when using redshifts derived with this relation - is also explained. The most
direct evidence in favour of the cannonball model presented here is its correct
description for the observed relation between narrow-spike width and amplitude
within a given GRB. There seems to be an indication for cosmological time
dilation in the total duration of GRBs, as expected in the cannonball model.
Quantitative predictions for the luminosity function of GRBs and the
``spectral-lag luminosity relation'' are given.

</DOC>
<DOC>
<DOCNO> 117324 </DOCNO>
On the Twin Non-paradox


  It is shown that the "twin paradox" arises from comparing unlike entities,
namely perceived intervals with eigenintervals. When this lacuna is closed, it
is seen that there is no twin paradox and that eigentime can serve as the
independent variable for mechanics in Special Relativity.

</DOC>
<DOC>
<DOCNO> 116511 </DOCNO>
High-harmonic generation from a confined atom


  The order of high harmonics emitted by an atom in an intense laser field is
limited by the so-called cutoff frequency. Solving the time-dependent
Schr\"odinger equation, we show that this frequency can be increased
considerably by a parabolic confining potential, if the confinement parameters
are suitably chosen.
 Furthermore, due to confinement, the radiation intensity remains high
throughout the extended emission range. All features observed can be explained
with classical arguments.

</DOC>
<DOC>
<DOCNO> 70429 </DOCNO>
Distinguishing between MSSM and NMSSM with e\gamma Scattering


  We study the associated production of selectrons and neutralinos with
subsequent leptonic decay of the selectron in e\gamma scattering within the
framework of MSSM and NMSSM. Due to the weak couplings of singlino dominated
neutralinos, associated neutralino production e^+ + e^- -> neutralino_1 +
neutralino_2 at a linear collider can be strongly suppressed in some regions of
the parameter space. Then the process e + gamma -> selectron_{L/R} +
neutralino_{1/2} -> e + neutralino_{1/2} + neutralino_1 can give additional
informations on the underlying theory and the character of neutralino_1 and
neutralino_2.

</DOC>
<DOC>
<DOCNO> 9106 </DOCNO>
XPS as a Probe of Gap Opening in Many Electron Systems


  Core hole photoemission (XPS) provides a powerful indirect probe of the low
energy excitations of a many electron system. We argue that XPS can be used to
study the way in which a gap opens at a metal-superconductor or metal-
insulator transition. We consider the "universal" physics of how the loss of
low energy excitations modifies XPS spectra in the context of several simple
models, considering in particular the case of a two dimensional d-wave
superconductor.

</DOC>
<DOC>
<DOCNO> 85239 </DOCNO>
Colliding Bubble Worlds


  We consider a cosmological model in which our Universe is a spherically
symmetric bubble wall in 5-dimensional anti-de Sitter spacetime. We argue that
the bubble on which we live will undergo collisions with other similar bubbles
and estimate the spectrum of such collisions. The collision rate is found to be
independent of the age of our Universe. Collisions with small bubbles provide
an experimental signature of this scenario, while collisions with larger
bubbles would be catastrophic.

</DOC>
<DOC>
<DOCNO> 83425 </DOCNO>
Extraction of semantic relations from a Basque monolingual dictionary


  This paper deals with the exploitation of dictionaries for the semi-automatic
construction of lexicons and lexical knowledge bases. The final goal of our
research is to enrich the Basque Lexical Database with semantic information
such as senses, definitions, semantic relations, etc., extracted from a Basque
monolingual dictionary. The work here presented focuses on the extraction of
the semantic relations that best characterise the headword, that is, those of
synonymy, antonymy, hypernymy, and other relations marked by specific relators
and derivation. All nominal, verbal and adjectival entries were treated. Basque
uses morphological inflection to mark case, and therefore semantic relations
have to be inferred from suffixes rather than from prepositions. Our approach
combines a morphological analyser and surface syntax parsing (based on
Constraint Grammar), and has proven very successful for highly inflected
languages such as Basque. Both the effort to write the rules and the actual
processing time of the dictionary have been very low. At present we have
extracted 42,533 relations, leaving only 2,943 (9%) definitions without any
extracted relation. The error rate is extremely low, as only 2.2% of the
extracted relations are wrong.

</DOC>
<DOC>
<DOCNO> 152222 </DOCNO>
Normalized Weyl-type $\star$-product on K\"ahler manifolds


  We define a normalized Weyl-type $\star$-product on general K\"{a}hler
manifolds. Expanding this product perturbatively we show that the cumbersome
term, which appears in a Berezin-type product, does not appear at least in the
first order of $\hbar$. This means a normalization factor, which is introduced
by Reshetikhin and Takhtajan for a Berezin-type product, is unnecessary for our
Weyl-type product at that order.

</DOC>
<DOC>
<DOCNO> 122598 </DOCNO>
Analysis of CMB foregrounds using a database for Planck


  Within the scope of the Planck IDIS (Integrated Data Information System)
project we have started to develop the data model for time-ordered data and
full-sky maps. The data model is part of the Data Management Component (DMC), a
software system designed according to a three-tier architecture which allows
complete separation between data storage and processing. The DMC is already
being used for simulation activities and the modeling of some foreground
components. We have ingested several Galactic surveys into the database and
used the science data-access interface to process the data. The data structure
for full-sky maps utilises the HEALPix tessellation of the sphere. We have been
able to obtain consistent measures of the angular power spectrum of the
Galactic radio continuum emission between 408 MHz and 2417 MHz.

</DOC>
<DOC>
<DOCNO> 151085 </DOCNO>
Supersymmetry in Singular Quantum Mechanics


  The breaking of supersymmetry due to singular potentials in supersymmetric
quantum mechanics is critically analyzed. It is shown that, when properly
regularized, these potentials respect supersymmetry, even when the
regularization parameter is removed.

</DOC>
<DOC>
<DOCNO> 68724 </DOCNO>
The QCD Coupling Constant


  This paper presents a summary of the current status of determinations of the
strong coupling constant alpha_s. A detailed description of the definition,
scale dependence and inherent theoretical ambiguities is given. The various
physical processes that can be used to determine alpha_s are reviewed and
attention is given to the uncertainties, both theoretical and experimental.

</DOC>
<DOC>
<DOCNO> 169905 </DOCNO>
Which Kind of Two-Particle States Can Be Teleported through a


  The use of a three-particle quantum channel to teleport entangled states
through a slight modification of the standard teleportation procedure is
studied. It is shown that it is not possible to perform successful
teleportation of an arbitrary and unknown two-particle entangled state,
following our version of the standard teleportation procedure. On the contrary,
it is shown which, and in how many different ways, particular classes of
two-particle states can be teleported.

</DOC>
<DOC>
<DOCNO> 71525 </DOCNO>
N = 2 Supersymmetry in a Hybrid Inflation Model


  The slow roll inflation requires an extremely flat inflaton potential. The
supersymmetry (SUSY) is not only motivated from the gauge hierarchy problem,
but also from stabilizing that flatness of the inflaton potential against
radiative corrections. However, it has been known that the Planck suppressed
higher order terms in the K\"ahler potential receive large radiative
corrections loosing the required flatness in the N = 1 supergravity. We propose
to impose a global N = 2 SUSY on the inflaton sector. What we find is that the
N = 2 SUSY Abelian gauge theory is exactly the same as the desired hybrid
inflation model. The flat potential at the tree level is not our choice of
parameters but a result of the symmetry. We further introduce a cut-off scale
of the theory which is lower than the Planck scale. This lower cut-off scale
suppresses the supergravity loop corrections to the flat inflaton potential.

</DOC>
<DOC>
<DOCNO> 14064 </DOCNO>
Antiferromagnetic Domains and Superconductivity in UPt3


  We explore the response of an unconventional superconductor to spatially
inhomogeneous antiferromagnetism (SIAFM). Symmetry allows the superconducting
order parameter in the E-representation models for UPt3 to couple directly to
the AFM order parameter. The Ginzburg-Landau equations for coupled
superconductivity and SIAFM are solved numerically for two possible SIAFM
configurations: (I) abutting antiferromagnetic domains of uniform size, and
(II) quenched random disorder of `nanodomains' in a uniform AFM background. We
discuss the contributions to the free energy, specific heat, and order
parameter for these models. Neither model provides a satisfactory account of
experiment, but results from the two models differ significantly. Our results
demonstrate that the response of an E_{2u} superconductor to SIAFM is strongly
dependent on the spatial dependence of AFM order; no conclusion can be drawn
regarding the compatibility of E_{2u} superconductivity with UPt3 that is
independent of assumptions on the spatial dependence of AFM

</DOC>
<DOC>
<DOCNO> 116844 </DOCNO>
The Flat Beam Experiment at the FNAL Photoinjector


  A technique for production of an electron beam with a high transverse
emittance ratio. a "flat" beam, has been proposed by Brinkmann, Derbenev, and
Floettmann.[1] The cathode of an RF-laser gun is immersed in a solenoidal
magnetic field; as a result the beam emitted from a round laser spot has a net
angular momentum. Subsequent passage through a quadrupole channel that has a 90
degree difference in phase advance between the transverse degrees of freedom
results in a flat beam. Experimental study is underway at the Fermilab A0
Photoinjector. Thus far, transverse emittance ratios as high as 50 have been
observed, and the results are in substantial agreement with simulation.
  [1] R. Brinkmann, Ya. Derbenev, K. Floettmann, "A Flat Beam Electron Source
for Linear Colliders." TESLA Note 99-09, April 1999.

</DOC>
<DOC>
<DOCNO> 101050 </DOCNO>
The Casson-Walker-Lescop Invariant and Link Invariants


  Formulas previously presented for the Casson-Walker invariant are generalized
to Lescop's extension. These formulas in terms of linking numbers and surgery
coefficients compute the change in Lescop's invariant under crossing changes in
a framed link presenting a 3-manifold. This leads us to revisit an old formula
for a coefficient of the Conway polynomial. Finally we compute Lescop's
invariant of several lens spaces and deduce some values for Dedekind sums.

</DOC>
<DOC>
<DOCNO> 69974 </DOCNO>
Luminosity of Asymmetric e+e- Collider with Coupling Lattices


  A formula of luminosity of asymmetric e+e- collider with coupled lattices is
derived explicitly. The calculation shows how the tilted angle and aspect ratio
of the beams affect the luminosity. Knowing the result of the calculation, we
measure the tilted angle of the luminous region of the collision for PEP-II
using two dimensional transverse scan of the luminosity. The method could be
applied to correct the coupling at the collision point.

</DOC>
<DOC>
<DOCNO> 11310 </DOCNO>
Comment on Dirac spectral sum rules for QCD_3


  Recently Magnea hep-th/9907096 , hep-th/9912207 [Phys.Rev.D61, 056005 (2000);
Phys.Rev.D62, 016005 (2000)] claimed to have computed the first sum rules for
Dirac operators in 3D gauge theories from 0D non-linear sigma models. I point
out that these computations are incorrect, and that they contradict with the
exact results for the spectral densities unambiguously derived from random
matrix theory by Nagao and myself.

</DOC>
<DOC>
<DOCNO> 99759 </DOCNO>
Permutations with restricted patterns and Dyck paths


  We exhibit a bijection between 132-avoiding permutations and Dyck paths.
Using this bijection, it is shown that all the recently discovered results on
generating functions for 132-avoiding permutations with a given number of
occurrences of the pattern $12... k$ follow directly from old results on the
enumeration of Motzkin paths, among which is a continued fraction result due to
Flajolet. As a bonus, we use these observations to derive further results and a
precise asymptotic estimate for the number of 132-avoiding permutations of
$\{1,2,...,n\}$ with exactly $r$ occurrences of the pattern $12... k$. Second,
we exhibit a bijection between 123-avoiding permutations and Dyck paths. When
combined with a result of Roblet and Viennot, this bijection allows us to
express the generating function for 123-avoiding permutations with a given
number of occurrences of the pattern $(k-1)(k-2)... 1k$ in form of a continued
fraction and to derive further results for these permutations.

</DOC>
<DOC>
<DOCNO> 101349 </DOCNO>
Noncommutative algebras associated to complexes and graphs


  This is a first of our papers devoted to "noncommutative topology and graph
theory". Its origin is the paper math.QA/0002238 by I. Gelfand, V. Retakh, and
R.L. Wilson where a new class of noncommutative algebras $Q_n$ was introduced.
The algebra $Q_n$ is closely related to factorizations of a generic polynomial
of degree $n$ over a division algebra into linear factors.

</DOC>
<DOC>
<DOCNO> 119323 </DOCNO>
A Measurement of the Temperature-Density Relation in the Intergalactic


  The evolution of the temperature in the intergalactic medium is related to
the reionization of hydrogen and helium, and has important consequences for our
understanding of the Lya forest and of galaxy formation in gravitational models
of large-scale structure. We measure the temperature-density relation of
intergalactic gas from Lya forest observations of eight quasar spectra with
high resolution and signal-to-noise ratio, using a new line fitting technique
to obtain a lower cutoff of the distribution of line widths from which the
temperature is derived. We carefully test the accuracy of this technique to
recover the gas temperature with a hydrodynamic simulation. The temperature at
redshift z=(3.9, 3.0, 2.4) is best determined at densities slightly above the
mean: T_star=(20200\pm2700, 20200\pm1300, 22600\pm1900)K (statistical error
bars) for gas density (in units of the mean density) Delta_star=(1.42\pm0.08,
1.37\pm0.11, 1.66\pm0.11). The power-law index of the temperature-density
relation, defined by T=T_star(Delta/Delta_star)^{gamma-1}, is gamma-1=
(0.43\pm0.45, 0.29\pm0.30, 0.52\pm0.14) for the same three redshifts. The
temperature at the fixed over-density Delta=1.4 is T_1.4=(20100\pm2800,
20300\pm1400, 20700\pm1900)K. These temperatures are higher than expected for
photoionized gas in ionization equilibrium with a cosmic background, and can be
explained by a gradual additional heating due to on-going HeII reionization.
The measurement of the temperature reduces one source of uncertainty in the
lower limit to the baryon density implied by the observed mean flux decrement.
We find that the temperature cannot be reliably measured for under-dense gas,
because the velocities due to expansion always dominate the widths of the
corresponding weak lines.

</DOC>
<DOC>
<DOCNO> 12015 </DOCNO>
Current Switch by Coherent Trapping of Electrons in Quantum Dots


  We propose a new transport mechanism through tunnel-coupled quantum dots
based on the coherent population trapping effect. Coupling to an excited level
by the coherent radiation of two microwaves can lead to an extremely narrow
current antiresonance. The effect can be used to determine interdot dephasing
rates and is a mechanism for a very sensitive, optically controlled current
switch.

</DOC>
<DOC>
<DOCNO> 122424 </DOCNO>
A Local Void and the Accelerating Universe


  Corresponding to the recent observational claims that we are in a local void
(an underdense region) on scales of 200 - 300 Mpc, the magnitude-redshift
relation in a cosmological model with a local void is investigated. It is
already evident that the accelerating behavior of high-z supernovae can be
explained in this model, because the local void plays a role similar to the
positive cosmological constant. In this paper the dependence of the behavior on
the gaps of cosmological parameters in the inner (low-density) region and the
outer (high-density) region, the radius of the local void, and the clumpiness
parameter is studied and its implication is discussed.

</DOC>
<DOC>
<DOCNO> 10026 </DOCNO>
Entropy, Dynamics and Instantaneous Normal Modes in a Random Energy


  It is shown that the fraction f of imaginary frequency instantaneous normal
modes (INM) may be defined and calculated in a random energy model(REM) of
liquids. The configurational entropy S and the averaged hopping rate among the
states R are also obtained and related to f, with the results R~f and
S=a+b*ln(f). The proportionality between R and f is the basis of existing INM
theories of diffusion, so the REM further confirms their validity. A link to S
opens new avenues for introducing INM into dynamical theories. Liquid 'states'
are usually defined by assigning a configuration to the minimum to which it
will drain, but the REM naturally treats saddle-barriers on the same footing as
minima, which may be a better mapping of the continuum of configurations to
discrete states. Requirements of a detailed REM description of liquids are
discussed.

</DOC>
<DOC>
<DOCNO> 13446 </DOCNO>
Fokker-Planck equations and density of states in disordered quantum


  We propose a general scheme to construct scaling equations for the density of
states in disordered quantum wires for all ten pure Cartan symmetry classes.
The anomalous behavior of the density of states near the Fermi level for the
three chiral and four Bogoliubov-de Gennes universality classes is analysed in
detail by means of a mapping to a scaling equation for the reflection from a
quantum wire in the presence of an imaginary potential.

</DOC>
<DOC>
<DOCNO> 121585 </DOCNO>
2MASS Observations of the Perseus, Orion A, Orion B, and Monoceros R2


  We use the 2MASS Second Incremental Release Point Source Catalog to
investigate the spatial distribution of young stars in the Perseus, Orion A,
Orion B, and MonR2 molecular clouds. After subtracting a semi-empirical model
of the field star contamination from the observed star counts, stellar surface
density maps are used to identify compact clusters and any stellar population
found more uniformly distributed over the molecular cloud. Each cloud contains
between 2 to 7 clusters, with at least half of the cluster population found in
a single, rich cluster. In addition, a distributed stellar population is
inferred in the Orion A and MonR2 molecular clouds within the uncertainties of
the field star subtraction with a surface density between 0.013 - 0.083
arcmin**-2. The fraction of the total stellar population contained in clusters
for the nominal extinction model ranges from ~50-100% if the distributed
population is relatively young (< 10 Myr), to ~25%-70% if it is relatively old
(~100 Myr). The relatively high fraction of stars contained in clusters
regardless of the age of the distributed population, in conjunction with the
young ages generally inferred for embedded clusters in nearby molecular clouds,
indicates that a substantial fraction of the total stellar population in these
regions has formed within the past few million years in dense clusters. This
suggests that either the star formation rate in each these clouds has recently
peaked if one assumes clouds have ages > 10 Myr, or molecular clouds are
younger than typically thought if one assumes that the star formation rate has
been approximately constant in time.

</DOC>
<DOC>
<DOCNO> 9465 </DOCNO>
Griffiths phase manifestation in disordered dielectrics


  We predict the existence of Griffith phase in the dielectrics with
concentrational crossover between dipole glass (electric analog of spin glass)
and ferroelectricity. The peculiar representatives of above substances are
$KTaO_3:Li$, $Nb$, $Na$ or relaxor ferroelectrics like
$Pb_{1-x}La_xZr_{0.65}Ti_{0.35}O_3$. Since this phase exists above
ferroelectric phase transition temperature (but below that temperature for
ordered substance), we call it "para-glass phase". We assert that the
difference between paraelectric and para-glass phase of above substances is the
existence of clusters (inherent to "ordinary" Griffiths phase in Ising magnets)
of correlated dipoles. We show that randomness play a decisive role in
Griffiths (para-glass) phase formation; this phase does not exist in a mean
field approximation.

</DOC>
<DOC>
<DOCNO> 39886 </DOCNO>
Search for Second and Third Generation Leptoquarks Including Production


  We report the results of a search for second and third generation leptoquarks
using 88 ${pb}^{-1}$ of data recorded by the Collider Detector at Fermilab.
Color triplet technipions, which play the role of scalar leptoquarks, are
investigated due to their potential production in decays of strongly coupled
color octet technirhos. Events with a signature of two heavy flavor jets and
missing energy may indicate the decay of a second (third) generation leptoquark
to a charm (bottom) quark and a neutrino. As the data is found to be consistent
with Standard Model expectations, mass limits are determined.

</DOC>
<DOC>
<DOCNO> 178447 </DOCNO>
Ground states of the Wick-Cutkosky model using light-front dynamics


  We consider the ground state in a model with scalar nucleons and a meson
using the formalism of light-front dynamics. Light-front potentials for
two-nucleon bound states are calculated using two approaches. First,
light-front time-ordered perturbation theory is used to calculate one- and
two-meson-exchange potentials. These potentials give results that agree well
with the ladder and ladder plus crossed box Bethe-Salpeter spectra. Secondly,
approximations that incorporate non-perturbative physics are used to calculate
alternative one-meson-exchange potentials. These non-perturbative potentials
give better agreement with the spectra of the full non-perturbative
ground-state calculation than the perturbative potentials. For lightly-bound
states, all of the approaches appear to agree with each other.

</DOC>
<DOC>
<DOCNO> 68989 </DOCNO>
Determination of $\gamma$ from $\bar B^0 \to K^-\pi^+, \pi^-\pi^+$


  Due a mistake in identifying the operators $O_9$ and $O_{10}$ which leads to
errorous expressions in eq. 9. With the correct expressions (exchange c_9 and
c_{10} in eq. 9), the analysis followed are invalide.

</DOC>
<DOC>
<DOCNO> 83205 </DOCNO>
A Simple Approach to Building Ensembles of Naive Bayesian Classifiers


  This paper presents a corpus-based approach to word sense disambiguation that
builds an ensemble of Naive Bayesian classifiers, each of which is based on
lexical features that represent co--occurring words in varying sized windows of
context. Despite the simplicity of this approach, empirical results
disambiguating the widely studied nouns line and interest show that such an
ensemble achieves accuracy rivaling the best previously published results.

</DOC>
<DOC>
<DOCNO> 178539 </DOCNO>
On the $\Lambda$ to $\Sigma^0$ ratio from proton-proton collisions


  We compare the recent COSY data on the total $pp{\to}p\Lambda{K^+}$ and
$pp{\to}p\Sigma^0{K^+}$ cross sections with the predictions from two boson
exchange models that either are based solely on $\pi$ and $K$ exchange or
include $\pi$, $\eta$ and $\rho$ exchange as well as the virtual excitation of
intermediate baryon resonances. Both models are found to reproduce the data
after the inclusion of final state hyperon-nucleon interactions. Thus, within
the experimental uncertainties, both models also roughly reproduce the strong
dependence of the $\Lambda$ to $\Sigma^0$ ratio as a function of the excess
energy near threshold, as well as at higher energies.

</DOC>
<DOC>
<DOCNO> 7729 </DOCNO>
Generalization of k.p theory for periodic perturbations


  We extend standard k.p theory to take into account periodic perturbations
which are rapidly oscillating with a wavelength of a few lattice constants. Our
general formalism allows us to explicitly consider the Bragg reflections due to
the perturbation-induced periodicity. As an example we calculate the effective
masses in the lowest two conduction bands of spontaneously ordered GaInP_2 as a
function of the degree of ordering. Comparison of our results for the lowest
conduction band to available experimental data and to first principle
calculations shows good agreement.

</DOC>
<DOC>
<DOCNO> 100363 </DOCNO>
Collapsing and Dirac-Type Operators


  We analyze the limit of the spectrum of a geometric Dirac-type operator under
a collapse with bounded diameter and bounded sectional curvature. In the case
of a smooth limit space B, we show that the limit of the spectrum is given by
the spectrum of a certain first-order differential operator on B, which can be
constructed using superconnections. In the case of a general limit space X, we
express the limit operator in terms of a transversally elliptic operator on a
G-space Y, with X = Y/G. As an application, we give a characterization of
manifolds which do not admit uniform upper bounds, in terms of diameter and
sectional curvature, on the k-th eigenvalue of the square of a Dirac-type
operator. We also give a formula for the essential spectrum of a Dirac-type
operator on a finite-volume manifold with pinched negative sectional curvature.

</DOC>
<DOC>
<DOCNO> 101120 </DOCNO>
Anyons and the elliptic Calogero-Sutherland model


  We obtain a second quantization of the elliptic Calogero-Sutherland (eCS)
model by constructing a quantum field theory model of anyons on a circle and at
a finite temperature. This yields a remarkable identity involving anyon
correlation functions and providing an algorithm for solving of the eCS model.
The eigenfunctions obtained define an elliptic generalization of the Jack
polynomials.

</DOC>
<DOC>
<DOCNO> 120808 </DOCNO>
What Kind of Obscured AGN Make the Cosmic X-ray Background?


  While it is understood that the origin of the Cosmic X-ray Background (CXRB)
can be explained in terms of a combination of obscured and unobscured AGN, the
identity of these obscured AGN showing up in large numbers at faint fluxes
remains unclear. Deep surveys are showing up increasingly large numbers of AGN
at the faintest fluxes which have broad optical lines but flat X-ray spectra.
It is commonly assumed that there must a new population of sources making a
substantial contribution to the CXRB. We show that we need not look further
than our own backyard to find familiar examples of such sources and there is no
compelling reason to invoke a mysterious, new population.

</DOC>
<DOC>
<DOCNO> 152213 </DOCNO>
M-theory duality and BPS-extended supergravity


  We discuss toroidal compactifications of maximal supergravity coupled to an
extended configuration of BPS states which transform consistently under the
U-duality group. Under certain conditions this leads to theories that live in
more than eleven spacetime dimensions, with maximal supersymmetry but only
partial Lorentz invariance. We demonstrate certain features of this
construction for the case of nine-dimensional N=2 supergravity.

</DOC>
<DOC>
<DOCNO> 69067 </DOCNO>
Neutrinos as Source of Ultra High Energy Cosmic Rays in Extra Dimensions


  If the neutrinos are to be identified with the primary source of ultra-high
energy cosmic rays(UHECR), their interaction on relic neutrinos is of great
importance in understanding their long intergalactic journey. In theories with
large compact dimensions, the exchange of a tower of massive spin-2 gravitons
(Kaluza-Klein excitations) gives extra contribution to $\nu\bar{\nu}
\longrightarrow f\bar{f}$ and $\gamma\gamma$ processes along with the opening
of a new channel for the neutrinos to annihilate with the relic cosmic neutrino
background $\nu\bar{\nu} \longrightarrow G_{kk}$ to produce bulk gravitons in
the extra dimensions. This will affect their attenuation. We compute the
contribution of these Kaluza-Klein excitations to the above processes and find
that for parameters of the theory constrained by supernova cooling, the
contribution does indeed become the dominant contribution above $\sqrt{s}
\simeq 300$ GeV.

</DOC>
<DOC>
<DOCNO> 9020 </DOCNO>
Stretched Exponential Relaxation on the Hypercube and the Glass


  We study random walks on the dilute hypercube using an exact enumeration
Master equation technique, which is much more efficient than Monte Carlo
methods for this problem. For each dilution $p$ the form of the relaxation of
the memory function $q(t)$ can be accurately parametrized by a stretched
exponential $q(t)=\exp(-(t/\tau)^\beta)$ over several orders of magnitude in
$q(t)$. As the critical dilution for percolation $p_c$ is approached, the time
constant $\tau(p)$ tends to diverge and the stretching exponent $\beta(p)$
drops towards 1/3. As the same pattern of relaxation is observed in wide class
of glass formers, the fractal like morphology of the giant cluster in the
dilute hypercube is a good representation of the coarse grained phase space in
these systems. For these glass formers the glass transition can be pictured as
a percolation transition in phase space.

</DOC>
<DOC>
<DOCNO> 85267 </DOCNO>
A New Interpretation of Compensate Effect


  A new interpretation of compensate effect is presented. The Hawking effect in
general space-time can be taken as a compensate effect of the scale
transformation of coordinate time on the horizon in generalized tortoise
coordinates transformation. It is proved that the Hawking temperature is the
pure gauge of compensate field in tortoise coordinates. This interpretation
does not refer to a zero-temperature space-time.

</DOC>
<DOC>
<DOCNO> 116354 </DOCNO>
Sampling Properties of the Spectrum and Coherency of Sequences of Action


  The spectrum and coherency are useful quantities for characterizing the
temporal correlations and functional relations within and between point
processes. This paper begins with a review of these quantities, their
interpretation and how th ey may be estimated. A discussion of how to assess
the statistical significance of features in these measures is included. In
addition, new work is presented which builds on the framework established in
the review section. This work inve stigates how the estimates and their error
bars are modified by finite sample si zes. Finite sample corrections are
derived based on a doubly stochastic inhomog eneous Poisson process model in
which the rate functions are drawn from a low va riance Gaussian process. It is
found that, in contrast to continuous processes, the variance of the estimators
cannot be reduced by smoothing beyond a scale wh ich is set by the number of
point events in the interval. Alternatively, the de grees of freedom of the
estimators can be thought of as bounded from above by th e expected number of
point events in the interval. Further new work describing and illustrating a
method for detecting the presence of a line in a point proces s spectrum is
also presented, corresponding to the detection of a periodic modul ation of the
underlying rate. This work demonstrates that a known statistical t est,
applicable to continuous processes, applies, with little modification, to point
process spectra, and is of utility in studying a point process driven by a
continuous stimulus. While the material discussed is of general applicability
to point processes attention will be confined to sequences of neuronal action
po tentials (spike trains) which were the motivation for this work.

</DOC>
<DOC>
<DOCNO> 70266 </DOCNO>
Deeply Virtual Compton Scattering and Skewed Parton Distribution


  An overview of the current status of and possible future theoretical,
phenomenological and experimental studies of DVCS and SPD's is presented.

</DOC>
<DOC>
<DOCNO> 11834 </DOCNO>
Multiple current reversals in forced inhomogeneous ratchets


  Transport properties of overdamped Brownian paricles in a rocked thermal
ratchet with space dependent friction coefficient is studied. By tuning the
parameters, the direction of current exhibit multiple reversals, both as a
function of the thermal noise strength as well as the amplitude of rocking
force. Current reversals also occur under deterministic conditions and exhibits
intriguing structure. All these features arise due to mutual interplay between
potential asymmetry,noise, driving frequency and inhomogeneous friction.

</DOC>
<DOC>
<DOCNO> 151222 </DOCNO>
Soliton Gauge States and T-duality of Closed Bosonic String Compatified


  We study soliton gauge states in the spectrum of bosonic string compatified
on torus. The enhenced Kac-Moody gauge symmetry, and thus T-duality, is shown
to be related to the existence of these soliton gauge states in some moduli
points.

</DOC>
<DOC>
<DOCNO> 170431 </DOCNO>
Quantum Zeno-like effect and spectra of particles in cascade transition


  Shr\"odinger equation for two-step spontaneous cascade transition in a
three-level quantum system is solved by means of Markovian approximation for
non-Markovian integro-differential evolution equations for amplitudes of
states. It is shown that both decay constant and radiation shift of initial
level are affected by instability of intermediate level of the cascade. These
phenomena are interpreted as the different manifestations of quantum Zeno-like
effect. The spectra of particles emitted during the cascade transition are
calculated in the general case and, in particular, for an unusual situation
when the initial state is lower than the intermediate one. It is shown that the
spectra of particles do not have a peak-like shape in the latter case.

</DOC>
<DOC>
<DOCNO> 174580 </DOCNO>
Thermal and electromagnetic properties of 166-Er and 167-Er


  The primary gamma-ray spectra of 166-Er and 167-Er are deduced from the
(3-He,alpha gamma) and (3-He,3-He' gamma) reaction, respectively, enabling a
simultaneous extraction of the level density and the gamma-ray strength
function. Entropy, temperature and heat capacity are deduced from the level
density within the micro-canonical and the canonical ensemble, displaying
signals of a phase-like transition from the pair-correlated ground state to an
uncorrelated state at Tc=0.5 MeV. The gamma-ray strength function displays a
bump around E-gamma=3 MeV, interpreted as the pygmy resonance.

</DOC>
<DOC>
<DOCNO> 10718 </DOCNO>
Dephasing times in quantum dots due to elastic LO phonon-carrier


  Interpretation of experiments on quantum dot (QD) lasers presents a
challenge: the phonon bottleneck, which should strongly suppress relaxation and
dephasing of the discrete energy states, often seems to be inoperative. We
suggest and develop a theory for an intrinsic mechanism for dephasing in QD's:
second-order elastic interaction between quantum dot charge carriers and
LO-phonons. The calculated dephasing times are of the order of 200 fs at room
temperature, consistent with experiments. The phonon bottleneck thus does not
prevent significant room temperature dephasing.

</DOC>
<DOC>
<DOCNO> 39941 </DOCNO>
Expected Coverage of Bayesian Confidence Intervals for the Mean of a


  Expected coverage and expected length of 90% upper and lower limit and 68.27%
central intervals are plotted as functions of the true signal for various
values of expected background. Results for several objective priors are shown,
and formulas for calculation of confidence intervals are obtained. For
comparison, expected coverage and length of frequentist intervals constructed
with the unified approach of Feldman and Cousins and a simple classical method
are also shown. It is assumed that the expected background is accurately known
prior to performing an experiment. The plots of expected coverage and length
are provided for values of signal and background typical for particle
experiments with small numbers of events.

</DOC>
<DOC>
<DOCNO> 121162 </DOCNO>
Assessing the state of galaxy formation


  We present the results of a survey of nearby, quiescent, non-peculiar,
extremely isolated galaxies to search for the gaseous remnants of galaxy
formation. Such remnants are predicted to persist around galaxies into the
present day by galaxy formation models. We find low-mass HI companions around 7
of 34 galaxies surveyed. In addition we find 5 galaxies with lopsided HI
distributions. The implications for galaxy formation and the nature of high
velocity clouds are discussed.

</DOC>
<DOC>
<DOCNO> 123187 </DOCNO>
Signatures of Galaxy-Cluster Interactions: Spiral Galaxy Rotation Curve


  The environmental dependencies of the characteristics of spiral galaxy
rotation curves are studied in this work. We use our large, homogeneously
collected sample of 510 cluster spiral galaxy rotation curves to test the claim
that the shape of a galaxy's rotation curve strongly depends on its location
within the cluster, and thus presumably on the strength of the local
intracluster medium and on the frequency and strength of tidal interactions
with the cluster and cluster galaxies. Our data do not corroborate such a
scenario, consistent with the fact that Tully-Fisher residuals are independent
of galaxy location within the cluster; while the average late-type spiral
galaxy shows more rise in the outer parts of its rotation curve than does the
typical early-type spiral galaxy, there is no apparent trend for either subset
with cluster environment. We also investigate as a function of cluster
environment rotation curve asymmetry and the radial distribution of H II region
tracers within galactic disks. Mild trends with projected cluster-centric
distance are observed: (i) the (normalized) radial extent of optical line
emission averaged over all spiral galaxy types shows a 4%+/-2% increase per Mpc
of galaxy-cluster core separation, and (ii) rotation curve asymmetry falls by a
factor of two between the inner and outer cluster for early-type spirals (a
negligible decrease is found for late-type spirals). Such trends are consistent
with spiral disk perturbations or even the stripping of the diffuse, outermost
gaseous regions within the disks as galaxies pass through the dense cluster
cores.

</DOC>
<DOC>
<DOCNO> 100253 </DOCNO>
Universal metric spaces according to W. Holsztynski


  We show, following W. Holsztynski, that there exists a continuous metric d on
the set of real numbers R such that any finite metric space is isometrically
embeddable into (R,d).

</DOC>
<DOC>
<DOCNO> 120100 </DOCNO>
X-rays from the barred galaxy NGC 4303


  The late-type galaxy NGC 4303 (M61) is one of the most intensively studied
barred galaxies in the Virgo Cluster. Its prominent enhanced star formation
throughout large areas of the disk can be nicely studied due to its low
inclination of about 27 \degr.
  We present observations of NGC 4303 with the ROSAT PSPC and HRI in the soft
X-ray (0.1-2.4 keV). The bulk of the X-ray emission is located at the nuclear
region. It contributes more than 80% to the total observed soft X-ray flux. The
extension of the central X-ray source and the L_X/L_Halpha ratio point to a low
luminous AGN (LINER) with a circumnuclear star-forming region. Several separate
disk sources can be distinguished with the HRI, coinciding spatially with some
of the most luminous HII regions outside the nucleus of NGC 4303. The total
star formation rate amounts to 1-2 Msun/yr. The X-ray structure follows the
distribution of star formation with enhancement at the bar-typical patterns.
  The best spectral fit consists of a power-law component (AGN and HMXBs) and a
thermal plasma component of hot gas from supernova remnants and superbubbles.
The total 0.1-2.4 keV luminosity of NGC 4303 amounts to 5x10^40 erg/s,
consistent with comparable galaxies, like e.g. NGC 4569.

</DOC>
<DOC>
<DOCNO> 178763 </DOCNO>
The reactions p + n --> d + omega and p + n --> d + phi near threshold


  The reactions p+n-->d+omega and p+n-->d+phi are studied within a relativistic
meson-exchange model of hadronic interactions. Predictions for the total cross
sections and for the angular distributions of the vector mesons are presented.
The resulting cross sections near threshold are around 10 - 30 microb for
p+n-->d+omega$ and 200 - 250 nb for p+n-->d+phi. A moderate deviation of the
cross section ratio sigma_{p+n-->d+phi} / sigma_{p+n-->d+omega} from that of
the Okubo-Zweig-Iizuka rule is predicted.

</DOC>
<DOC>
<DOCNO> 69114 </DOCNO>
Spherically Symmetric Simulation with Boltzmann Neutrino Transport of


  We present a spherically symmetric, Newtonian core-collapse simulation of a
15 solar mass star with a 1.28 solar mass iron core. The time-, energy-, and
angle-dependent transport of electron neutrinos and antineutrinos was treated
with a new code which iteratively solves the Boltzmann equation and the
equations for neutrino number, energy and momentum to order O(v/c) in the
velocity v of the stellar medium. The supernova shock expands to a maximum
radius of 350 km instead of only about 240 km as in a comparable calculation
with multi-group flux-limited diffusion (MGFLD) by Bruenn, Mezzacappa, & Dineva
(1995). This may be explained by stronger neutrino heating due to the more
accurate transport in our model. Nevertheless, after 180 ms of expansion the
shock finally recedes to a radius around 250 km (compared to about 170 km in
the MGFLD run). The effect of an accurate neutrino transport is helpful, but
not large enough to cause an explosion of the considered 15 solar mass star.
Therefore postshock convection and/or an enhancement of the core neutrino
luminosity by convection or reduced neutrino opacities in the neutron star seem
necessary for neutrino-driven explosions of such stars. We find an electron
fraction Y_e > 0.5 in the neutrino-heated matter, which suggests that the
overproduction problem of neutron-rich nuclei with mass numbers around A = 90
in exploding models may be absent when a Boltzmann solver is used for the
electron neutrino and antineutrino transport.

</DOC>
<DOC>
<DOCNO> 70106 </DOCNO>
Supersymmetric Large Extra Dimensions Are Small and/or Numerous


  Recently, a scenario has been proposed in which the gravitational scale could
be as low as the TeV scale, and extra dimensions could be large and detectable
at the electroweak scale. Although supersymmetry is not a requirement of this
scenario, it is nevertheless true that its best-motivated realizations arise in
supersymmetric theories (like M theory). We argue here that supersymmetry can
have robust, and in some instances fatal, implications for the expected
experimental signature for TeV-scale gravity. The signature of the
supersymmetric version of the scenario differs most dramatically from what has
been considered in the literature because mass splittings within the gravity
supermultiplet in these models are extremely small, implying in particular the
existence of a very light spin-one superpartner for the graviton. We compute
the implications of this graviphoton, and show that it can acquire
dimension-four couplings to ordinary matter which can strongly conflict with
supernova bounds.

</DOC>
<DOC>
<DOCNO> 11239 </DOCNO>
Monte Carlo Simulations of Spin Glasses at Low Temperatures


  We report the results of Monte Carlo simulations on several spin glass models
at low temperatures. By using the parallel tempering (Exchange Monte Carlo)
technique we are able to equilibrate down to low temperatures, for moderate
sizes, and hence the data should not be affected by critical fluctuations. Our
results for short range models are consistent with a picture proposed earlier
that there are large scale excitations which cost only a finite energy in the
thermodynamic limit, and these excitations have a surface whose fractal
dimension is less than the space dimension. For the infinite range Viana-Bray
model, our results obtained for a similar number of spins are consistent with
standard replica symmetry breaking.

</DOC>
<DOC>
<DOCNO> 121298 </DOCNO>
Multiphase Gas in Intermediate Redshift Galaxies


  We present 40 quasar absorption line systems at intermediate redshifts (z~1),
with focus on one of the most kinematically complex known, as examples of how
the unique capabilities of space-based and ground-based facilities can be
combined to glean much broader insights into astrophysical systems.

</DOC>
<DOC>
<DOCNO> 151525 </DOCNO>
String Theory: The Early Years


  Lenny Susskind has made many important contributions to theoretical physics
during the past 35 years. In this talk I will discuss the early history of
string theory (1968-72) emphasizing Susskind's contributions.

</DOC>
<DOC>
<DOCNO> 102335 </DOCNO>
Unitary Irreducible Representations of a Lie Algebra for Matrix Chain


  There is a decomposition of a Lie algebra for open matrix chains akin to the
triangular decomposition. We use this decomposition to construct unitary
irreducible representations. All multiple meson states can be retrieved this
way. Moreover, they are the only states with a finite number of non-zero
quantum numbers with respect to a certain set of maximally commuting linearly
independent quantum observables. Any other state is a tensor product of a
multiple meson state and a state coming from a representation of a quotient
algebra that extends and generalizes the Virasoro algebra. We expect the
representation theory of this quotient algebra to describe physical systems at
the thermodynamic limit.

</DOC>
<DOC>
<DOCNO> 85074 </DOCNO>
Black holes: new horizons


  This is a review of current black-hole theory, concentrating on local,
dynamical aspects.

</DOC>
<DOC>
<DOCNO> 151324 </DOCNO>
Non-Abelian Born-Infeld Action and Solitons for Critical Non-BPS Branes


  The non-abelian flat directions in the tachyon potential of stable non-BPS
branes recently found are shown to persist to all orders in alpha' at tree
level in the string coupling. We also obtain the non-abelian Born-Infeld action
including the tachyon potential for a stack of stable non-BPS branes on a
critical orbifold. Finally we discuss stable soliton states on the non-BPS
brane.

</DOC>
<DOC>
<DOCNO> 119530 </DOCNO>
1E 0117.2-2837 and the NLR of Narrow-Line Seyfert 1 galaxies


  Based on photoionization calculations we present a study of the NLR emission
line ratios of Narrow-line Seyfert 1 (NLS1) galaxies. In particular, we
investigate the influence of different EUV - soft-X-ray spectral shapes (a
giant soft excess, a steep X-ray powerlaw, the presence of a warm absorber) and
NLR cloud properties (density, abundances, distance from the continuum source)
on the predicted optical emission-line ratios like [OIII] and [FeXIV].

</DOC>
<DOC>
<DOCNO> 10744 </DOCNO>
Frequency Dependence of Magnetopolarizability of Mesoscopic Grains


  We calculate average magnetopolarizability of an isolated metallic sample at
frequency $\omega$ comparable to the mean level spacing $\Delta$. The frequency
dependence of the magnetopolarizability is described by a universal function of
$\omega/\Delta$.

</DOC>
<DOC>
<DOCNO> 151058 </DOCNO>
Five-Dimensional Gauge Theories and Local Mirror Symmetry


  We study the dynamics of 5-dimensional gauge theory on $M_4\times S^1$ by
compactifying type II/M theory on degenerate Calabi-Yau manifolds. We use the
local mirror symmetry and shall show that the prepotential of the 5-dimensional
SU(2) gauge theory without matter is given exactly by that of the type II
string theory compactified on the local ${\bf F}_2$, i.e. Hirzebruch surface
${\bf F}_2$ lying inside a non-compact Calabi-Yau manifold. It is shown that
our result reproduces the Seiberg-Witten theory at the 4-dimensional limit
$R\to 0$ ($R$ denotes the radius of $S^1$) and also the result of the
uncompactified 5-dimensional theory at $R\to \infty$. We also discuss SU(2)
gauge theory with $1\le N_f\le 4$ matter in vector representations and show
that they are described by the geometry of the local ${\bf F}_2$ blown up at
$N_f$ points.

</DOC>
<DOC>
<DOCNO> 70988 </DOCNO>
Hadron Structure and Modern Spectroscopy


  The colour, flavour, spin and J^PC of glueballs and hybrid mesons and baryons
are constructed in an intuitive manner in both the gluon counting and adiabatic
definitions. Glueball decay, production and mixing and hybrid meson decay
selection rules and production are clarified.

</DOC>
<DOC>
<DOCNO> 119881 </DOCNO>
Properties of the double beta model for intracluster gas


  We present an extensive study of the double beta model for the X-ray surface
brightness profiles of clusters, and derive analytically the gas density and
total masses of clusters under the hydrostatic equilibrium hypothesis. It is
shown that the employment of the double beta model instead of the conventional
single beta model can significantly improve the goodness of fit to the observed
X-ray surface brightness profiles of clusters, which will in turn lead to a
better determination of the gas and total mass distributions in clusters. In
particular, the observationally fitted beta parameter for the extended
component in a double beta model may become larger. This opens a new
possibility of resolving the long-standing beta discrepancy for clusters. Using
an ensemble of 33 ROSAT PSPC observed clusters drawn from the Mohr, Mathiesen &
Evrard (1999) sample, we find that the asymptotic value of beta_{fit} is
(0.83+-0.33) at large radii, consistent with both the average spectroscopic
parameter beta_{spec}=(0.78+-0.37) and the result given by numerical
simulations.

</DOC>
<DOC>
<DOCNO> 100874 </DOCNO>
Holomorphic Principal Bundles Over Elliptic Curves II: The Parabolic


  This paper continues the study of holomorphic semistable principal G-bundles
over an elliptic curve. In this paper, the moduli space of all such bundles is
constructed by considering deformations of a minimally unstable G-bundle. The
set of all such deformations can be described as the C^* quotient of the
cohomology group of a sheaf of unipotent groups, and we show that this quotient
has the structure of a weighted projective space. We identify this weighted
projective space with the moduli space of semistable G-bundles, giving a new
proof of a theorem of Looijenga.

</DOC>
<DOC>
<DOCNO> 102655 </DOCNO>
Cech-De Rham theory for leaf spaces of foliations


  The purpose of this paper is to present a ``Cech-De Rham'' model for the
cohomology of leaf spaces. This model lends itself to the construction of
characteristic classes (in the cohomology of classifying spaces) by explicit
geometrical constructions which are immediate extensions of the standard
constructions for manifolds. In particular we rediscover (and explain) the
Thurston formula and the Bott formulas for cocycles on diffeomorphism groups.
We also use the Cech-De Rham model to explicitly describe the relation between
the cohomology of the classifying space, the basic cohomology, and the foliated
cohomology of foliations.

</DOC>
<DOC>
<DOCNO> 121240 </DOCNO>
Black Holes in Centers of Disk Galaxies - Spectroscopy with a Wide Slit


  Motivated by STIS observations of more than 50 nearby galactic nuclei, we
consider long-slit emission-line spectra when the slit is wider than the
instrumental PSF. The finite width of the slit generates complex patterns in
the spectra that can have considerable diagnostic power if they are modeled
with adequate sophistication. They allowed us to develop a new method for
estimating the BH mass that gives fuller information and higher sensitivity to
BH detection than traditional methods.

</DOC>
<DOC>
<DOCNO> 12870 </DOCNO>
Possible alterations of the gravitational field in a superconductor


  In this paper I calculate the possible alteration of the gravitational field
in a superconductor by using the time-dependent Ginzburg-Landau equations
(TDGL). I compare the behaviour of a high-Tc superconductor (HTCS) like
YBa_2Cu_3O_7 (YBCO) with a classical low-Tc superconductor (LTCS) like Pb.
Finally, I discuss what values of the parameters characterizing a
superconductor can enhance the reduction of gravitational field.

</DOC>
<DOC>
<DOCNO> 151414 </DOCNO>
Non local parity transformations and anomalies


  We present an alternative derivation of the parity anomaly for a massless
Dirac field in 2+1 dimensions coupled to a gauge field. The anomaly functional,
a Chern-Simons action for the gauge field, is obtained from the non-trivial
Jacobian corresponding to a non local symmetry of the Pauli-Villars regularized
action. That Jacobian is well-defined, finite, and yields the standard
Chern-Simons term when the cutoff tends to infinity.

</DOC>
<DOC>
<DOCNO> 13366 </DOCNO>
Non-Markovian quantum kinetics and conservation laws


  A link between memory effects in quantum kinetic equations and nonequilibrium
correlations associated with the energy conservation is investigated. In order
that the energy be conserved by an approximate collision integral, the
one-particle distribution function and the mean interaction energy are treated
as independent nonequilibrium state parameters. The density operator method is
used to derive a kinetic equation in second-order non-Markovian Born
approximation and an evolution equation for the nonequilibrium
quasi-temperature which is thermodynamically conjugated to the mean interaction
energy. The kinetic equation contains a correlation contribution which exactly
cancels the collision term in thermal equilibrium and ensures the energy
conservation in nonequilibrium states. Explicit expressions for the entropy
production in the non-Markovian regime and the time-dependent correlation
energy are obtained.

</DOC>
<DOC>
<DOCNO> 122930 </DOCNO>
Precession of Magnetically Driven Warped Disks and Low-Frequency QPOs in


  An accretion disk around a rotating magnetized star is subjected to magnetic
torques which induce disk warping and precession. These torques arise from
interactions between the stellar field and the induced surface currents on the
disk. Applying these new effects to weakly magnetized ($B\sim 10^7-10^9$G)
neutron stars in low-mass X-ray binaries, we study the global hydrodynamical
warping/precession modes of the disk under the combined influences of
relativistic frame dragging, classical precession due to the oblateness of the
neutron star, and the magnetic torques. Under quite general conditions, the
magnetic warping torque can overcome the ``Bardeen-Petterson'' viscous damping
and makes the modes grow. The modes are confined to the inner region of the
disk, and have frequencies close to the sum of the Lense-Thirring frequency,
the classical precession frequency, and the magnetically driven precession
frequency evaluated at the inner disk radius $r_{in}$. As $\dot M$ increases,
the mode frequency is reduced relative to the total precession frequency at
$r_{in}$ since the mode is less concentrated around $r_{in}$ due to the
increasing viscous stress associated with the large $\dot M$. Because of this,
and because the magnetically driven precession is retrograde and depends
strongly on $\dot M$, the mode frequency can have a non-monotonic dependence on
$\dot M$. This may account for several observed features of low-frequency
(10--60 Hz) quasi-periodic oscillations (LFQPOs) in low-mass X-ray binaries
which are otherwise difficult to explain, such as the flattening/turnover in
the LFQPO frequency--$\dot M$ correlation or in the LFQPO frequency--kHz QPO
frequency correlation (e.g., as seen clearly in GX 17+2).

</DOC>
<DOC>
<DOCNO> 8759 </DOCNO>
Magnetic field dependence of the superconducting fluctuation


  The dependence of the Maki-Thompson (MT) and of the density of states
depletion (DOS) contributions from superconducting fluctuations (SF) to NMR-NQR
relaxation is derived in the framework of the diagrammatic theory, applied to
layered three dimensional (3D) high T_c superconductors. The regularization
procedure devised for the conductivity (Buzdin and Varlamov, Phys. Rev. B, 58,
14195 (1998)) is used in order to avoid the divergence of the DOS term. The
theoretical results are discussed in the light of NMR-NQR measurements in YBCO
and compared with the recent theory (Eschrig et al., Phys. Rev. B 59, 12095
(1999)), based on the assumption of a purely 2D spectrum of fluctuations.

</DOC>
<DOC>
<DOCNO> 117609 </DOCNO>
H2 emission as a diagnostic of physical processes in starforming


  Observations and interpretation of extragalactic rotational and rovibrational
H2 emission are reviewed. Direct observations of H2 lines do not trace bulk H2
mass, but excitation rate. As such, the H2 lines are unique diagnostics, if the
excitation mechanism can be determined, which generally requires high-quality
spectroscopy and suitable additional data. The diagnostic power of the H2 lines
is illustrated by two cases studies: H2 purely rotational line emission from
the disk of the nearby spiral galaxy NGC891 and high resolution imaging and
spectroscopy of H2 vibrational line emision from the luminous merger NGC6240.

</DOC>
<DOC>
<DOCNO> 151855 </DOCNO>
Harmonic Superspaces and Superconformal Fields


  Representations of four-dimensional superconformal groups on harmonic
superfields are discussed. It is argued that any representation can be given as
a superfield on many superflag manifolds. Representations on analytic
superspaces do not require constraints. We discuss short representations and
how to obtain them as explicit products of fundamental fields. We also discuss
superfields that transform under supergroups.

</DOC>
<DOC>
<DOCNO> 12858 </DOCNO>
Surface molecular dynamics simulation with two orthogonal surface steps:


  Due to particle conservation, Canonical Molecular Dynamics (MD) simulations
fail in the description of surface phase transitions involving coverage or
lateral density changes. However, a step on the surface can act effectively as
a source or a sink of atoms, in the simulation as well as in real life. A
single surface step can be introduced by suitably modifying planar Periodic
Boundary Conditions (PBC), to accommodate the generally inequivalent stacking
of two adjacent layers. We discuss here how, through the introduction of two
orthogonal surface steps, particle number conservation may no longer represent
a fatal constraint for the study of these surface transitions. As an example,
we apply the method for estimating temperature-induced lateral density increase
of the reconstructed
 Au (001) surface; the resulting anisotropic cell change is consistent with
experimental observations. Moreover, we implement this kind of scheme in
conjunction with the variable curvature MD method, recently introduced by our
group.

</DOC>
<DOC>
<DOCNO> 102329 </DOCNO>
Finsler Metrics of Constant Positive Curvature on the Lie Group $s^3$


  Guided by the Hopf fibration, we single out a family (indexed by a positive
constant K) of right invariant Riemannian metrics on the Lie group $S^3$. Using
the Yasuda-Shimada theorem as an inspiration, we determine for each K>1 a
privileged right invariant Killing field of constant length. Each such
Riemannian metric pairs with the corresponding Killing field to produce a
y-global and {\it explicit} Randers metric on $S^3$. Using the machinery of
spray curvature and Berwald's formula for it, we prove directly that the said
Randers metric has constant positive flag curvature K, as predicted by the
Yasuda-Shimada theorem. We also explain why this family of Finslerian space
forms is NOT projectively flat.

</DOC>
<DOC>
<DOCNO> 102509 </DOCNO>
Vector Fields, Invariant Varieties and Linear Systems


  We investigate the interplay between invariant varieties of vector fields and
the inflection locus of linear systems with respect to the vector field. Among
the consequences of such investigation we obtain a computational criteria for
the existence of rational first integrals of a given degree, bounds for the
number of first integrals on families of vector fields and a generalization of
Darboux's criteria. We also provide a new proof of Gomez-Mont's result on
foliations with all leaves algebraic.

</DOC>
<DOC>
<DOCNO> 101848 </DOCNO>
Quantum differential operators on the quantum plane


  The universal enveloping algebra U(g) of a Lie algebra g acts on its
representation ring R through D(R), the ring of differential operators on R. A
quantised universal enveloping algebra (or "quantum group") is a deformation of
a universal enveloping algebra and acts not through the differential operators
of its representation ring but through the quantised differential operators of
its representation ring. We present this situation for the quantum group of
sl_2.

</DOC>
<DOC>
<DOCNO> 150442 </DOCNO>
Auxiliary representations of Lie algebras and the BRST constructions


  The method of construction of auxiliary representations for a given Lie
algebra is discussed in the framework of the BRST approach. The corresponding
BRST charge turns out to be non -- hermitian. This problem is solved by the
introduction of the additional kernel operator in the definition of the scalar
product in the Fock space. The existence of the kernel operator is proven for
any Lie algebra.

</DOC>
<DOC>
<DOCNO> 83214 </DOCNO>
Practical Reasoning for Expressive Description Logics


  Description Logics (DLs) are a family of knowledge representation formalisms
mainly characterised by constructors to build complex concepts and roles from
atomic ones. Expressive role constructors are important in many applications,
but can be computationally problematical. We present an algorithm that decides
satisfiability of the DL ALC extended with transitive and inverse roles, role
hierarchies, and qualifying number restrictions. Early experiments indicate
that this algorithm is well-suited for implementation. Additionally, we show
that ALC extended with just transitive and inverse roles is still in PSPACE.
Finally, we investigate the limits of decidability for this family of DLs.

</DOC>
<DOC>
<DOCNO> 7666 </DOCNO>
Nonadiabatic noncyclic geometric phase of a spin-1/2 particle subject to


  We derive a formula of the nonadiabatic noncyclic Pancharatnam phase for a
quantum spin-1/2 particle subject to an arbitrary magnetic field. The formula
is applied to three specific kinds of magneic fields. (i) For an orientated
magnetic field, the Pancharatnam phase is derived exactly. (ii) For a rotating
magnetic field, the evolution equation is solved analytically. The
Aharonov-Anandan phase is obtained exactly and the Pancharatnam phase is
computed numerically. (iii) We propose a kind of topological transition in
one-dimensional mesoscopic ring subject to an in-plane magnetic field, and then
address the nonadiabatic noncyclic effect on this phenomenon.

</DOC>
<DOC>
<DOCNO> 178460 </DOCNO>
Phenomenological aspects of kaon photoproduction on the nucleon


  Using an isobar model which can reproduce the existing experimental data of
kaon photoproduction on the nucleon we investigate some related
phenomenological aspects, i.e. the hadronic form factors, contributions of
kaon-hyperon final states to the anomalous magnetic moment of the nucleon, and
missing nucleon resonances. By reggeizing the appropriate propagators we extend
the model to the higher photon energy regime.

</DOC>
<DOC>
<DOCNO> 119998 </DOCNO>
Gas, Stars and Baryons in Low Surface Brightness Galaxies


  Recent surveys have discovered hundreds of low surface brightness galaxies in
the local (z < 0.1) Universe. Plots of the surface brightness distribution (the
space density of galaxies plotted against central surface brightness) show a
flat distribution from the bright-end cutoff of 21.65 through the current
observational limit of 25.0 B mag arcsec^{-2}. As no trend is seen to indicate
the size or mass of galaxies decreases with decreasing central surface
brightness, it is likely that a significant percentage of the baryon content in
the universe is contained in these diffuse systems. In this paper I briefly
review the known properties of low surface brightness galaxies, and describe
some current theories on the baryonic mass fraction of low surface brightness
systems and their consequences.

</DOC>
<DOC>
<DOCNO> 9922 </DOCNO>
Field behavior of an Ising model with aperiodic interactions


  We derive exact renormalization-group recursion relations for an Ising model,
in the presence of external fields, with ferromagnetic nearest-neighbor
interactions on Migdal-Kadanoff hierarchical lattices. We consider layered
distributions of aperiodic exchange interactions, according to a class of
two-letter substitutional sequences. For irrelevant geometric fluctuations, the
recursion relations in parameter space display a nontrivial uniform fixed point
of hyperbolic character that governs the universal critical behavior. For
relevant fluctuations, in agreement with previous work, this fixed point
becomes fully unstable, and there appears a two-cycle attractor associated with
a new critical universality class.

</DOC>
<DOC>
<DOCNO> 119238 </DOCNO>
FUSE Observations of Interstellar Gas Towards the LMC Star Sk -67 05


  We report on measurements of interstellar O VI, H2, P II, Si II, Ar I, and Fe
II absorption along the line of sight to Sk -67 05, a B0 Ia star in a diffuse H
II region in the western edge of the Large Magellanic Cloud (LMC). We find log
N(O VI) = 14.40 +/- 0.04 in the Milky Way (MW) component and, using the C IV
column density from previous IUE observations, N(C IV) / N(O VI) = 1.00 +/-
0.16, a value similar to other halo measurements made with FUSE. In the LMC
component, log N(O VI) = 13.89 +/- 0.05, and N(C IV) / N(O VI) < 0.4 (3 sigma),
since only an upper limit on N(C IV) is available. Along this sightline the LMC
is rich in molecular hydrogen, log N(H2) = 19.50 +/- 0.08; in the MW log N(H2)
= 14.95 +/- 0.08. A two-component fit for the excitation temperature of the
molecular gas in the LMC gives T_01 = 59 +/- 5 K for J=0,1 and T_ex = 800 +/-
330 K for J=3,4,5. For the MW, T_01 = 99 (+30/-20) K; no excitation temperature
could be determined for the higher rotational states. The MW and LMC gas-phase
[Fe/P] abundances are ~0.6 and ~0.7 dex lower, respectively, than solar system
abundances. These values are similar to [Fe/Zn] measurements for the MW and LMC
towards SN 1987A.

</DOC>
<DOC>
<DOCNO> 169739 </DOCNO>
Space Searches with a Quantum Robot


  Quantum robots are described as mobile quantum computers and ancillary
systems that move in and interact with arbitrary environments. Their dynamics
is given as tasks which consist of sequences of alternating computation and
action phases. A task example is considered in which a quantum robot searches a
space region to find the location of a system. The possibility that the search
can be more efficient than a classical search is examined by considering use of
Grover's Algorithm to process the search results. For reversible searches this
is problematic for two reasons. One is the removal of entanglements generated
by the search process. The other is that even if the entanglement can be
avoided, the search process in 2-D space regions is no more efficient than a
classical search. However, quantum searches of space regions with 3 or more
dimensions are more efficient than classical searches. Reasons why quantum
robots are interesting independent of these results are briefly summarized.

</DOC>
<DOC>
<DOCNO> 152290 </DOCNO>
Graded q-pseudo-differential Operators and Supersymmetric Algebras


  We give a supersymmetric generalization of the sine algebra and the quantum
algebra $U_{t}(sl(2))$. Making use of the $q$-pseudo-differential operators
graded with a fermionic algebra, we obtain a supersymmetric extension of sine
algebra. With this scheme we also get a quantum superalgebra $U_{t}(sl(2/1)$.

</DOC>
<DOC>
<DOCNO> 39931 </DOCNO>
A measurement of the tau mass and the first CPT test with tau leptons


  We measure the mass of the tau lepton to be 1775.1+-1.6(stat)+-1.0(syst.) MeV
using tau pairs from Z0 decays. To test CPT invariance we compare the masses of
the positively and negatively charged tau leptons. The relative mass difference
is found to be smaller than 3.0 10^-3 at the 90% confidence level.

</DOC>
<DOC>
<DOCNO> 40304 </DOCNO>
Measurement of $A_c$ with Charmed Mesons at SLD


  We present a direct measurement of the parity-violation parameter $A_c$ in
the coupling of the $Z^0$ to $c$-quarks with the SLD detector. The measurement
is based on a sample of 530k hadronic $Z^0$ decays, produced with a mean
electron-beam polarization of $|P_e| = 73 %$. The tagging of $c$-quark events
is performed using two methods: the exclusive reconstruction of $D^{\ast+}$,
$D^+$, and $D^0$ mesons, and the soft-pions ($\pi_s$) produced in the decay of
$D^{\ast+}\to D^0 \pi_s^+$. The large background from $D$ mesons produced in
$B$ hadron decays is separated efficiently from the signal using precision
vertex information. The combination of these two methods yields $A_c = 0.688
\pm 0.041.$

</DOC>
<DOC>
<DOCNO> 12066 </DOCNO>
Generalized quasiperiodic Rauzy tilings


  We present a geometrical description of new canonical $d$-dimensional
codimension one quasiperiodic tilings based on generalized Fibonacci sequences.
These tilings are made up of rhombi in $2d$ and rhombohedra in $3d$ as the
usual Penrose and icosahedral tilings. Thanks to a natural indexing of the
sites according to their local environment, we easily write down, for any
approximant, the sites coordinates, the connectivity matrix and we compute the
structure factor.

</DOC>
<DOC>
<DOCNO> 7909 </DOCNO>
Acoustic fluidization for earthquakes?


  Melosh [1996] has suggested that acoustic fluidization could provide an
alternative to theories that are invoked as explanations for why some crustal
faults appear to be weak. We show that there is a subtle but profound
inconsistency in the theory that unfortunately invalidates the results. We
propose possible remedies but must acknowledge that the relevance of acoustic
fluidization remains an open question.

</DOC>
<DOC>
<DOCNO> 174581 </DOCNO>
Measurement of the recoil polarization in the p (\vec e, e' \vec p) pi^0


  The recoil proton polarization has been measured in the p (\vec e,e'\vec p)
pi^0 reaction in parallel kinematics around W = 1232 MeV, Q^2 = 0.121 (GeV/c)^2
and epsilon = 0.718 using the polarized c.w. electron beam of the Mainz
Microtron. Due to the spin precession in a magnetic spectrometer, all three
proton polarization components P_x/P_e = (-11.4 \pm 1.3 \pm 1.4) %, P_y =
(-43.1 \pm 1.3 \pm 2.2) %, and P_z/P_e = (56.2 \pm 1.5 \pm 2.6) % could be
measured simultaneously. The Coulomb quadrupole to magnetic dipole ratio CMR =
(-6.4\pm 0.7_{stat}\pm 0.8_{syst}) % was determined from P_x in the framework
of the Mainz Unitary Isobar Model. The consistency among the reduced
polarizations and the extraction of the ratio of longitudinal to transverse
response is discussed.

</DOC>
<DOC>
<DOCNO> 120756 </DOCNO>
Comparison Between Extrasolar Planets and Low-Mass Secondaries


  This paper compares the statistical features of the sample of discovered
extrasolar planets with those of the secondaries in nearby spectroscopic
binaries, in order to enable us to distinguish between the two populations.
Based on 32 planet candidates discovered until March 2000, we find that their
eccentricity and period distribution are surprisingly similar to those of the
binary population, while their mass distribution is remarkably different. The
mass distributions definitely support the idea of two distinct populations,
suggesting the planet candidates are indeed extrasolar planets. The transition
between the two populations probably occurs at 10--30 Jupiter masses. We point
out a possible negative correlation between the orbital period of the planets
and the metallicity of their parent stars, which holds only for periods less
than about 100 days. These short-period systems are characterized by circular
or almost circular orbits.

</DOC>
<DOC>
<DOCNO> 10661 </DOCNO>
Fluid and plastic flow dynamics of the critical state for a strongly


  We present simulations of the dynamic critical state for a 2D superconductor
with strong pinning centers, corresponding to a matching field twice the
applied magnetic field. The sharp crossover between the plastic regime, at low
current density and temperature, and the fluid flow regime for flux motion is
characterized by the activation energy for flux motion and the transverse
diffusion of the vortices trajectory.

</DOC>
<DOC>
<DOCNO> 68863 </DOCNO>
Inflation After Preheating


  Preheating after inflation may lead to nonthermal phase transitions with
symmetry restoration. These phase transitions may occur even if the total
energy density of fluctuations produced during reheating is relatively small as
compared with the vacuum energy in the state with restored symmetry. As a
result, in some inflationary models one encounters a secondary, nonthermal
stage of inflation due to symmetry restoration after preheating. We review the
theory of nonthermal phase transitions and make a prediction about the
expansion factor during the secondary inflationary stage. We then present the
results of lattice simulations which verify these predictions, and discuss
possible implications of our results for the theory of formation of topological
defects during nonthermal phase transitions.

</DOC>
<DOC>
<DOCNO> 13813 </DOCNO>
Time-Dependent Density-Functional Theory for Superfluids


  A density-functional theory is established for inhomogeneous superfluids at
finite temperature, subject to time-dependent external fields in isothermal
conditions. After outlining parallelisms between a neutral superfluid and a
charged superconductor, Hohenberg-Kohn-Sham-type theorems are proved for
gauge-invariant densities and a set of Bogolubov-Popov equations including
exchange and correlation is set up. Earlier results applying in the linear
response regime are recovered.

</DOC>
<DOC>
<DOCNO> 174524 </DOCNO>
The RHIC Zero Degree Calorimeter


  High Energy collisions of nuclei usually lead to the emission of evaporation
neutrons from both ``beam'' and ``target'' nuclei. At the RHIC heavy ion
collider with 100GeV/u beam energy, evaporation neutrons diverge by less than
$~2$ milliradians from the beam axis Neutral beam fragments can be detected
downstream of RHIC ion collisions (and a large aperture Accelerator dipole
magnet) if $\theta\leq$ 4 mr but charged fragments in the same angular range
are usually too close to the beam trajectory.
  In this 'zero degree' region produced particles and other secondaries deposit
negligible energy when compared with that of beam fragmentation neutrons.
  The purpose of the RHIC zero degree calorimeters (ZDC's) is to detect
neutrons emitted within this cone along both beam directions and measure their
total energy (from which we calculate multiplicity). The ZDC coincidence of the
2 beam directions is a minimal bias selection of heavy ion collisions. This
makes it useful as an event trigger and a luminosity monitor\cite{baltz} and
for this reason we built identical detectors for all 4 RHIC experiments.
  The neutron multiplicity is also known to be correlated with event geometry
\cite{appel} and will be used to measure collision centrality in mutual beam
int eractions.

</DOC>
<DOC>
<DOCNO> 11311 </DOCNO>
Dynamics of evaporative cooling in magnetically trapped atomic hydrogen


  We study the evaporative cooling of magnetically trapped atomic hydrogen on
the basis of the kinetic theory of a Bose gas. The dynamics of trapped atoms is
described by the coupled differential equations, considering both the
evaporation and dipolar spin relaxation processes. The numerical time-evolution
calculations quantitatively agree with the recent experiment of Bose-Einstein
condensation with atomic hydrogen. It is demonstrated that the balance between
evaporative cooling and heating due to dipolar relaxation limits the number of
condensates to 9x10^8 and the corresponding condensate fraction to a small
value of 4% as observed experimentally.

</DOC>
<DOC>
<DOCNO> 9845 </DOCNO>
Magnetoresistance From Quantum Interference Effects in Ferromagnets


  The desire to maximize the sensitivity of read/write heads and thus the
information density of magnetic storage devices has produced an intense
interest in the magnetoresistance (MR) of magnetic materials. Recent
discoveries include "colossal" MR of the manganites1-4 and the enhanced MR of
low carrier density ferromagnets4-6. In the low carrier density systems
investigated to date as well as the manganites, a key feature is that the
electrical conduction is due to a different set of electrons than the localized
electrons responsible for the magnetism. Here we propose a mechanism for
ferromagnetic MR originating from quantum interference effects, rather than
simple scattering. The new mechanism obtains in disordered low carrier density
magnets where the magnetism as well as the electrical conduction are due to the
same electrons. Here the MR is positive and only weakly temperature dependent
below the Curie point. This is very different from the MR seen when conduction
electrons and local moments can be treated separately, in which case the MR is
negative and strongly peaked at the Curie point.

</DOC>
<DOC>
<DOCNO> 8000 </DOCNO>
Universality Class of Thermally Diluted Ising Systems at Criticality


  The universality class of thermally diluted Ising systems, in which the
realization of the disposition of magnetic atoms and vacancies is taken from
the local distribution of spins in the pure original Ising model at
criticality, is investigated by finite size scaling techniques using the Monte
Carlo method. We find that the critical temperature, the critical exponents and
therefore the universality class of these thermally diluted Ising systems
depart markedly from the ones of short range correlated disordered systems. Our
results agree fairly well with theoretical predictions previously made by
Weinrib and Halperin for systems with long range correlated disorder.

</DOC>
<DOC>
<DOCNO> 102023 </DOCNO>
Discrete symmetries as automorphisms of the proper Poincare group


  We present the consistent approach to finding the discrete transformations in
the representation spaces of the proper Poincar\'e group. To this end we use
the possibility to establish a correspondence between involutory automorphisms
of the proper Poincar\'e group and the discrete transformations. As a result,
we derive rules of the discrete transformations for arbitrary spin-tensor
fields without the use of relativistic wave equations. Besides, we construct
explicitly fields carrying representations of the extended Poincar\'e group,
which includes the discrete transformations as well.

</DOC>
<DOC>
<DOCNO> 8073 </DOCNO>
Quasiparticle resonant states as a probe of short-range electronic


  The recently observed properties of quasiparticle resonant states near
impurities on the surface of superconducting BSCCO demonstrate that in-plane
Andreev processes are either absent or phase-incoherent. Analysis of the
spectral and spatial details of the electronic structure near a Zn impurity
also suggest an effective magnetic component of the impurity potential. Further
experiments are proposed to clarify whether the effective moments of nearby
impurities are correlated.

</DOC>
<DOC>
<DOCNO> 12614 </DOCNO>
q-Boson approach to multiparticle correlations


  An approach is proposed enabling to effectively describe, for relativistic
heavy-ion collisions, the observed deviation from unity of the intercept
\lambda (measured value corresponding to zero relative momentum {\bf p} of two
registered identical pions or kaons) of the two-particle correlation function
C(p,K). The approach uses q-deformed oscillators and the related picture of
ideal gas of q-bosons. In effect, the intercept \lambda is connected with
deformation parameter q. For a fixed value of q, the model predicts specific
dependence of \lambda on pair mean momentum {\bf K} so that, when |{\bf
K}|\gsim 500 - 600 MeV/c for pions or when |{\bf K}|\gsim 700 - 800 MeV/c for
kaons, the intercept \lambda tends to a constant which is less than unity and
determined by q. If q is fixed to be the same for pions and kaons, the
intercepts \lambda_\pi and \lambda_K essentially differ at small mean momenta
{\bf K}, but tend to be equal at {\bf K} large enough (|{\bf K}|\gsim 800MeV/c)
where the effect of resonance decays can be neglected. We argue that it is of
basic interest to check in the experiments on heavy ion collisions: (i) the
exact shape of dependence \lambda = \lambda({\bf K}), and (ii) whether for
|{\bf K}| \gsim 800 MeV/c the resulting \lambda_\pi and \lambda_K indeed
coincide.

</DOC>
<DOC>
<DOCNO> 150546 </DOCNO>
Riemann surfaces and Schrodinger potentials of gauged supergravity


  Supersymmetric domain-wall solutions of maximal gauged supergravity are
classified in 4, 5 and 7 dimensions in the presence of non-trivial scalar
fields taking values in the coset SL(N, R)/SO(N) for N=8, 6 and 5 respectively.
We use an algebro-geometric method based on the Christoffel-Schwarz
transformation, which allows for the characterization of the solutions in terms
of Riemann surfaces whose genus depends on the isometry group. The
uniformization of the curves can be carried out explicitly for models of low
genus and results into trigonometric and elliptic solutions for the scalar
fields and the conformal factor of the metric. The Schrodinger potentials for
the quantum fluctuations of the graviton and scalar fields are derived on these
backgrounds and enjoy all properties of supersymmetric quantum mechanics.
Special attention is given to a class of elliptic models whose quantum
fluctuations are commonly described by the generalized Lame potential
\mu(\mu+1)P(z) + \nu(\nu+1)P(z+\omega_1)+ \kappa(\kappa+1)P(z+\omega_2) +
\lambda(\lambda+1)P(z+\omega_1 +\omega_2) for the Weierstrass function P(z) of
the underlying Riemann surfaces with periods 2\omega_1 and 2\omega_2, for
different half-integer values of the coupling constants \mu, \nu, \kappa,
\lambda.

</DOC>
<DOC>
<DOCNO> 121467 </DOCNO>
Measurement of intrinsic alignments in galaxy ellipticities


  We measure the alignment of galaxy ellipticities in the local universe over a
range of scales using digitized photographic data from the SuperCOSMOS Sky
Survey. We find for a magnitude cut of b_J < 20.5, corresponding to a median
galaxy redshift of z = 0.1, and 2x10^6 galaxies, that the galaxy ellipticities
exhibit a non-zero correlation over a range of scales between 1 and 100
arcminutes. In particular, we measure the variance of mean galaxy
ellipticities, sg^2(theta), in square angular cells on the sky as a function of
cell size and find it lies in the range, 2 x 10^{-4} > sg^2(theta) > 1 x
10^{-5} for cell side lengths between 15 < theta < 100 arcminutes. Considering
the low median redshift of the galaxies in the sample and hence the relatively
low effective cross-section for lensing of these galaxies by the large-scale
structure of the Universe, we propose that we have detected an intrinsic
alignment of galaxy ellipticities. We compare our results to recent analytical
and numerical predictions made for the intrinsic galaxy alignment and find good
agreement. We discuss the importance of these results for measuring cosmic
shear from upcoming shallow surveys (e.g. Sloan Digital Sky Survey) and we
outline how these measurements could possibly be used to constrain models of
galaxy formation and/or measure the mass distribution in the local universe.

</DOC>
<DOC>
<DOCNO> 121261 </DOCNO>
Complex Visibilities of Cosmic Microwave Background Anisotropies


  We study the complex visibilities of the cosmic microwave background
anisotropies that are observables in interferometric observations of the cosmic
microwave background, using the multipole expansion methods commonly adopted in
analyzing single-dish experiments. This allows us to recover the properties of
the visibilities that is obscured in the flat-sky approximation. Discussions of
the window function, multipole resolution, instrumental noise, pixelization,
and polarization are given.

</DOC>
<DOC>
<DOCNO> 100662 </DOCNO>
Homology surgery and invariants of 3-manifolds


  We introduce a homology surgery problem in dimension 3 which has the property
that the vanishing of its algebraic obstruction leads to a canonical class of
\pi-algebraically-split links in 3-manifolds with fundamental group \pi . Using
this class of links, we define a theory of finite type invariants of
3-manifolds in such a way that invariants of degree 0 are precisely those of
conventional algebraic topology and surgery theory. When finite type invariants
are reformulated in terms of clovers, we deduce upper bounds for the number of
invariants in terms of \pi-decorated trivalent graphs. We also consider an
associated notion of surgery equivalence of \pi-algebraically split links and
prove a classification theorem using a generalization of Milnor's
\mu-invariants to this class of links.

</DOC>
<DOC>
<DOCNO> 84186 </DOCNO>
Dirac--Maxwell Solitons


  Detailed analysis of the coupled Dirac-Maxwell equations and the structure of
their solutions is presented. Numerical solutions of the field equations in the
case of spherical symmetry with negligible gravitational self-interaction
reveal the existence of families of solitons with electric field dominance that
are completely determined by the observed charge and mass of the underlying
particles. A soliton is found which has the charge and mass of the electron as
well as a charge radius of 10^{-23} m. This is well within the present
experimentally determined upper limit of ~ 10^{-18} m. Properties of these
particles as well as possible extension to the work herein are discussed.

</DOC>
<DOC>
<DOCNO> 118148 </DOCNO>
An X-ray Flare Detected on the M8 Dwarf VB 10


  We have detected an X-ray flare on the very low mass star VB 10 (GL 752 B; M8
V) using the ROSAT High Resolution Imager. VB 10 is the latest type (lowest
mass) main sequence star known to exhibit coronal activity. X-rays were
detected from the star during a single 1.1-ksec segment of an observation which
lasted 22 ksec in total. The energy released by this flare is on the order of
10^27 ergs/sec. This is at least two orders of magnitude greater than the
quiescent X-ray luminosity of VB 10, which has yet to be measured. This X-ray
flare is very similar in nature to the far ultraviolet flare which was observed
by Linsky et al. (1995) using the Goddard High Resolution Spectrograph onboard
Hubble Space Telescope. We discuss reasons for the extreme difference between
the flare and quiescent X-ray luminosities, including the possibility that VB
10 has no quiescent (10^6 K) coronal plasma at all.

</DOC>
<DOC>
<DOCNO> 100603 </DOCNO>
Locally compact quantum groups in the von Neumann algebraic setting


  In this paper we complete in several aspects the picture of locally compact
quantum groups. First of all we give a definition of a locally compact quantum
group in the von Neumann algebraic setting and show how to deduce from it a
C*-algebraic quantum group. Further we prove several results about locally
compact quantum groups which are important for applications, but were not yet
settled in our paper "Locally compact quantum groups". We prove a serious
strengthening of the left invariance of the Haar weight, and we give several
formulas connecting the locally compact quantum group with its dual. Loosely
speaking we show how the antipode of the locally compact quantum group
determines the modular group and modular conjugation of the dual locally
compact quantum group.

</DOC>
<DOC>
<DOCNO> 71728 </DOCNO>
Higher-Fock States and the Covariance of the Light-Front Quark Model


  The light-front quark model has been successful in describing various meson
properties. We apply the model to the meson weak decays and discuss the
covariance of the model. We find that the inclusion of the higher-Fock
state(i.e. nonvalence or so called Z-graph) contributions is necessary to
recover the covariance of the light-front quark model. We present the
possibility of the effective calculation of the higher-Fock state contributions
to restore the covarince in the light-front model.

</DOC>
<DOC>
<DOCNO> 170719 </DOCNO>
Realization of quantum process tomography in NMR


  Quantum process tomography is a procedure by which the unknown dynamical
evolution of an open quantum system can be fully experimentally characterized.
We demonstrate explicitly how this procedure can be implemented with a nuclear
magnetic resonance quantum computer. This allows us to measure the fidelity of
a controlled-not logic gate and to experimentally investigate the error model
for our computer. Based on the latter analysis, we test an important assumption
underlying nearly all models of quantum error correction, the independence of
errors on different qubits.

</DOC>
<DOC>
<DOCNO> 121761 </DOCNO>
BeppoSAX observations of three distant, highly luminous clusters of


  We present an analysis of BeppoSAX observations of three clusters of galaxies
which are amongst the most luminous in the Universe: RXJ1347-1145, Zwicky 3146
and Abell 2390. Using data from both the Low Energy (LECS) and Medium Energy
(MECS) Concentrator Spectrometers, and a joint analysis with the Phoswich
Detection System (PDS) data above 10 keV, we constrain, with a relative
uncertainty of between 7 and 42 per cent (90 per cent confidence level), the
mean gas temperature in the three clusters. These measurements are checked
against any possible non-thermal contribution to the plasma emission and are
shown to be robust. We confirm that RXJ1347-1145 has a gas temperature that
lies in the range between 13.2 and 22.3 keV at the 90 per cent confidence
level, and is larger than 12.1 keV at 3 sigma level. The existence of such a
hot galaxy cluster at redshift of about 0.45 implies an upper limit on the mean
mass density in the Universe, Omega_m, of 0.5. Combining the BeppoSAX estimates
for gas temperature and luminosity of the three clusters presented in this work
with ASCA measurements available in the literature, we obtain a slope of 2.7 in
the L-T relation once the physical properties are corrected from the
contamination from the central cooling flows.

</DOC>
<DOC>
<DOCNO> 12652 </DOCNO>
Fluctuations Of WIG-the index of Warsaw Stock Exchange. Preliminary


  A time series that represents daily values of the WIG index (the main index
of Warsaw Stock Exchange) over last 5 years is examined. Non-Gaussian features
of distributions of fluctuations, namely returns, over a time scale are
considered. Some general properties like exponents of the long range
correlation estimated by averaged volatility and detrended fluctuations
analysis (DFA) as well as exponents describing a decay of tails of the
cumulative distributions are found. Closing, the Zipf analysis for the WIG
index time series translated into three letter text is presented.

</DOC>
<DOC>
<DOCNO> 122473 </DOCNO>
Compton Scattering in Static and Moving Media. II. System-Frame


  I study the formation of Comptonization spectra in spherically symmetric,
fast moving media in a flat spacetime. I analyze the mathematical character of
the moments of the transfer equation in the system-frame and describe a
numerical method that provides fast solutions of the time-independent radiative
transfer problem that are accurate in both the diffusion and free-streaming
regimes. I show that even if the flows are mildly relativistic (V~0.1, where V
is the electron bulk velocity in units of the speed of light), terms that are
second-order in V alter the emerging spectrum both quantitatively and
qualitatively. In particular, terms that are second-order in V produce
power-law spectral tails, which are the dominant feature at high energies, and
therefore cannot be neglected. I further show that photons from a static source
are upscattered by the bulk motion of the medium even if the velocity field
does not converge. Finally, I discuss these results in the context of radial
accretion onto and outflows from compact objects.

</DOC>
<DOC>
<DOCNO> 100679 </DOCNO>
An example concerning Ohtsuki's invariant and the full SO(3) quautum


  Two lens spaces are given to show that Ohtsuki's $\tau$ for rational homology
spheres does not determine Kirby-Melvin's $\{\tau_r^{'}, r odd\geq3\}$

</DOC>
<DOC>
<DOCNO> 72073 </DOCNO>
Classical and Quantum Brane Cosmology


  The first part of this lecture quickly touches upon some important but
infrequently discussed issues in large extra dimension and warped extra
dimension scenarios, with particular reference to effects in the early
universe. The second part discusses a modification and extension of an earlier
proposal by Brown and Teitelboim to relax the effective cosmological term by
nucleation of fundamental membranes.

</DOC>
<DOC>
<DOCNO> 14093 </DOCNO>
Phase transition in the collisionless regime for wave-particle


  Gibbs statistical mechanics is derived for the Hamiltonian system coupling
self-consistently a wave to N particles. This identifies Landau damping with a
regime where a second order phase transition occurs. For nonequilibrium initial
data with warm particles, a critical initial wave intensity is found: above it,
thermodynamics predicts a finite wave amplitude in the limit of infinite N;
below it, the equilibrium amplitude vanishes. Simulations support these
predictions providing new insight on the long-time nonlinear fate of the wave
due to Landau damping in plasmas.

</DOC>
<DOC>
<DOCNO> 101408 </DOCNO>
Quantization of Lie bialgebras and shuffle algebras of Lie algebras


  To any field K of characteristic 0, we associate a set Sha(K). Elements of
Sha(K) are equivalence classes of families of Lie polynomials subject to
associativity relations. We construct an injection and a retraction between
Sha(K) and the set of quantization functors of Lie bialgebras over K. This
construction involves the following steps. 1) To each element \varpi of Sha(K),
we associate a functor g\mapsto Sh(g) from the category of Lie algebras to that
of Hopf algebras; Sh(g) contains Ug. 2) When g and h are Lie algebras, and
r_{gh} \in g\otimes h, we construct an element R(r_{gh}) of Sh(g)\otimes Sh(h)
satisfying quasitriangularity identities; R(r_{gh}) defines a Hopf algebra
morphism from Sh(g)^* to Sh(h). 3) When g = h and r\in g\otimes g is a solution
of CYBE, we construct a series \rho(r) such that R(\rho(r)) is a solution of
QYBE. The expression of \rho(r) in terms of r involves Lie polynomials, and we
show that this expression is unique at a universal level. This step relies on
vanishing statements for cohomologies arising from universal algebras for the
solutions of CYBE. 4) We define the quantization of a Lie bialgebra g as the
image of the morphism defined by R(\rho(r)), where r\in g\otimes g^* is the
canonical element attached to g.

</DOC>
<DOC>
<DOCNO> 84337 </DOCNO>
Kinematics of vector fields


  Different (not only by sign) affine connections are introduced for
contravariant and covariant tensor fields over a differentiable manifold by
means of a non-canonical contraction operator, defining the notion dual bases
and commuting with the covariant and with the Lie-differential operator.
Classification of the linear transports on the basis of the connections between
the connections is given. Notion of relative velocity and relative acceleration
for vector fields are determined. By means of these kinematic characteristics
several other types of notions as shear velocity, shear acceleration, rotation
velocity, rotation acceleration, expansion velocity and expansion acceleration
are introduced and on their basis auto-parallel and non-isotropic (non-null)
vector fields are classified.

</DOC>
<DOC>
<DOCNO> 70311 </DOCNO>
Theory of the nucleon spin-polarizabilities I


  I summarize the theoretical predictions for the spin-dependent nucleon
polarizabilities based on chiral effective field theory approaches.

</DOC>
<DOC>
<DOCNO> 100272 </DOCNO>
Z_3-graded exterior differential calculus and gauge theories of higher


  We present a possible generalization of the exterior differential calculus,
based on the operator d such that d^3=0, but d^2\not=0. The first and second
order differentials generate an associative algebra; we shall suppose that
there are no binary relations between first order differentials, while the
ternary products will satisfy the cyclic relations based on the representation
of cyclic group Z_3 by cubic roots of unity. We shall attribute grade 1 to the
first order differentials and grade 2 to the second order differentials; under
the associative multiplication law the grades add up modulo 3. We show how the
notion of covariant derivation can be generalized with a 1-form A, and we give
the expression in local coordinates of the curvature 3-form. Finally, the
introduction of notions of a scalar product and integration of the Z_3-graded
exterior forms enables us to define variational principle and to derive the
differential equations satisfied by the curvature 3-form. The Lagrangian
obtained in this way contains the invariants of the ordinary gauge field tensor
F_{ik} and its covariant derivatives D_i F_{km}.

</DOC>
<DOC>
<DOCNO> 151911 </DOCNO>
Quantum fields in anti de Sitter spacetime and degrees of freedom in the


  The quantization of a scalar field in anti de Sitter spacetime using
Poincar\'e coordinates is considered. We find a discrete spectrum that is
consistent with a possible mapping between bulk and boundary quantum states.

</DOC>
<DOC>
<DOCNO> 9981 </DOCNO>
Interlayer Tunneling of Quasiparticles and Cooper Pairs in Bi-2212


  The interlayer tunneling has been studied on high quality Bi-2212 stacks of
micron to the submicron lateral size. We found that low temperature and low
voltage tunneling I-V characteristics can be self-consistently described by
Fermi-liquid model for a d-wave superconductor with a significant contribution
from coherent interlayer tunneling. The gap and pseudogap interplay with
variation of temperature and magnetic field has been extracted from the I-V
characteristics. We consider also the role of charging effects for submicron
stacks.

</DOC>
<DOC>
<DOCNO> 9107 </DOCNO>
Signatures of granular microstructure in dense shear flows


  Granular materials react to shear stresses differently than do ordinary
fluids. Rather than deforming uniformly, materials such as dry sand or
cohesionless powders develop shear bands: narrow zones containing large
relative particle motion leaving adjacent regions essentially rigid[1,2,3,4,5].
Since shear bands mark areas of flow, material failure and energy dissipation,
they play a crucial role for many industrial, civil engineering and geophysical
processes[6]. They also appear in related contexts, such as in lubricating
fluids confined to ultra-thin molecular layers[7]. Detailed information on
motion within a shear band in a three-dimensional geometry, including the
degree of particle rotation and inter-particle slip, is lacking. Similarly,
only little is known about how properties of the individual grains - their
microstructure - affect movement in densely packed material[5]. Combining
magnetic resonance imaging, x-ray tomography, and high-speed video particle
tracking, we obtain the local steady-state particle velocity, rotation and
packing density for shear flow in a three-dimensional Couette geometry. We find
that key characteristics of the granular microstructure determine the shape of
the velocity profile.

</DOC>
<DOC>
<DOCNO> 68814 </DOCNO>
Transverse Spin in QCD. I. Canonical Structure


  In this work we initiate a systematic investigation of the spin of a
composite system in an arbitrary reference frame in QCD. After a brief review
of the difficulties one encounters in equal-time quantization, we turn to
light-front quantization. We show that, in spite of the complexities,
light-front field theory offers a unique opportunity to address the issue of
relativistic spin operators in an arbitrary reference frame since boost is
kinematical in this formulation. Utilizing this symmetry, we show how to
introduce transverse spin operators for massless particles in an arbitrary
reference frame in analogy with those for massive particles. Starting from the
manifestly gauge invariant, symmetric energy momentum tensor in QCD, we derive
expressions for the interaction dependent transverse spin operators ${\cal
J}^i$ ($i=1,2$) which are responsible for the helicity flip of the nucleon in
light-front quantization. In order to construct ${\cal J}^i$, first we derive
expressions for the transverse rotation operators $F^i$. In the gauge $A^+=0$,
we eliminate the constrained variables. In the completely gauge fixed sector,
in terms of the dynamical variables, we show that one can decompose ${\cal
J}^i= {\cal J}^i_I + {\cal J}^i_{II} + {\cal J}^i_{III}$ where only ${\cal
J}^i_{I}$ has explicit coordinate ($x^-, x^i$) dependence in its integrand. The
operators ${\cal J}^i_{II}$ and ${\cal J}^i_{III}$ arise from the fermionic and
bosonic parts respectively of the gauge invariant energy momentum tensor. We
discuss the implications of our results.

</DOC>
<DOC>
<DOCNO> 101767 </DOCNO>
A New Convexity Result and the Multiple Access Channel


  We compute the capacity region of the s-sender Multiple Access Adder Channel
in information theory and obtain an explicit description of this region as only
one polyhedron, instead of a convex hull of infinitely many polyhedrons. We
obtain this by proving a conjecture raised by Lindstrom in 1975, which in turn
follows from certain convexity results, both continuous and discrete.

</DOC>
<DOC>
<DOCNO> 151633 </DOCNO>
Holographic principle and field-to-particle transition formalism in


  The paper consists of two parts which seem to be independent of each other
but at first glance only. In the Part one the field-to-particle transition
formalism is applied to the sigma model (string), dilaton gravity and gauged
supergravity 0-brane solutions. In addition to the fact that the
field-to-particle transition is of interest itself it can be regarded also as
the dynamical dimensional reduction which takes into account field fluctuations
as well as one can treat it as the method of the consistent quantization in the
vicinity of the nontrivial vacuum induced by a field solution. It is shown that
in all the cases the end product of the approach is the so-called "non-minimal
point particle". In view of this it is conjectured that point particles are not
only the end product but also the underlying base of modern high-energy theory
even more fundamental than the strings. The Part two is hence devoted to the
formal axiomatics of the string-brane approach - there we deepen the
above-mentioned conjecture. It turns out that a point particle can be regarded
as an extended object from the viewpoint of a macroscopic measurement. The
particle is actually observed as the ``cloud'' consisting of the virtual paths
and nothing prevents their deviations from the classical trajectory. Therefore,
for an observer the real particle can be no more viewed as a point object.
However, it cannot be supposed also as a continuous extended object unless we
average over all the deviations. Then we obtain the metabrane, which is the
composite extended object consisting of the microscopical objects (strings) and
cosmological-size ones (3-brane) where the size of a corresponding embedding is
governed by the weight constants arising along with the decomposition.

</DOC>
<DOC>
<DOCNO> 100635 </DOCNO>
Un theoreme de Cartier-Milnor-Moore-Quillen pour les bigebres


  We define an equivalence of categories, quite similar to the classical
Cartier-Milnor-Moore-Quillen theorem, between the category of connected
dendriform bialgebras and the category of brace algebras. This equivalence is
given by the functors "subspace of primitive elements" and "universal
enveloping dendriform algebra".

</DOC>
<DOC>
<DOCNO> 68399 </DOCNO>
Phi-measure of pions in high energy heavy-ion collisions


  Event-by-Event fluctuations for high energy heavy-ion collisions are
investigated. The $\Phi$-measures are calculated for pions. It is found that
multiparticle symmetrization correlation has great influence on the value of
$\Phi$ if the phase space density is high. Previous derivation of
$\Phi$-measure has neglected multiparticle quantum correlation. So the
explanation of $\Phi$-measure as a measure of dynamical correlation is
reasonable only when multiparticles quantum correlation effects are smaller. We
argue that the $\Phi$-measure might be applicable at the SPS energy where the
pion phase space density is much less than one.

</DOC>
<DOC>
<DOCNO> 119022 </DOCNO>
ROSAT HRI and ASCA Observations of the Spiral Galaxy NGC 6946 and Its


  Analysis of 80 ksec ASCA and 60 ksec ROSAT HRI observations of the face-on
spiral galaxy NGC 6946 are presented. The ASCA image is the first observation
of this galaxy above ~2 keV. Diffuse emission may be present in the inner ~4'
extending to energies above ~2-3 keV. In the HRI data, fourteen point-like
sources are detected, the brightest two being a source very close to the
nucleus and a source to the northeast that corresponds to a luminous complex of
interacting supernova remnants (SNRs). We detect a point source that lies
\~30$''$ west of the SNR complex but with a luminosity ~1/15 of it. None of the
point sources shows evidence of strong variability; weak variability would
escape our detection.
  The ASCA spectrum of the SNR complex shows evidence for an emission line at
\~0.9 keV which could be either Ne IX at ~0.915 keV or a blend of ion stages of
Fe L-shell emission if the continuum is fit with a power law. However, a two
component, Raymond-Smith thermal spectrum with no lines gives an equally valid
continuum fit and may be more physically plausible given the observed spectrum
below 3 keV. Adopting this latter model, we derive a density for the SNR
complex of 10-35 cm^{-3}, consistent with estimates inferred from optical
emission line ratios. The complex's extraordinary X-ray luminosity may be
related more to the high density of the surrounding medium than to a small but
intense interaction region where two of the complex's SNRs are apparently
colliding.

</DOC>
<DOC>
<DOCNO> 100541 </DOCNO>
Automatic closure of invariant linear manifolds for operator algebras


  Kadison's transitivity theorem implies that, for irreducible representations
of C*-algebras, every invariant linear manifold is closed. It is known that CSL
algebras have this propery if, and only if, the lattice is hyperatomic (every
projection is generated by a finite number of atoms). We show several other
conditions are equivalent, including the conditon that every invariant linear
manifold is singly generated.
  We show that two families of norm closed operator algebras have this
property. First, let L be a CSL and suppose A is a norm closed algebra which is
weakly dense in Alg L and is a bimodule over the (not necessarily closed)
algebra generated by the atoms of L. If L is hyperatomic and the compression of
A to each atom of L is a C*-algebra, then every linear manifold invariant under
A is closed. Secondly, if A is the image of a strongly maximal triangular AF
algebra under a multiplicity free nest representation, where the nest has order
type -N, then every linear manifold invariant under A is closed and is singly
generated.

</DOC>
<DOC>
<DOCNO> 69102 </DOCNO>
Non-unitarity of CKM matrix from the vector singlet quark mixing and


  In the standard model (SM) the lowest order contribution to the quark
electric dipole moment (EDM) occurs at the three loop level. We show that the
non-unitarity of the CKM matrix in models with an extended quark sector
typically gives rise to a quark EDM at the two loop level which has no GIM-like
suppression factors except the external quark mass. The induced neutron EDM is
of order 10^{-29} e cm and can be well within the reach of the next
generation of experiments if it is further enhanced by long distance physics as
happens in the SM.

</DOC>
<DOC>
<DOCNO> 119559 </DOCNO>
ISOPHOT observations of 3CR quasars and radio galaxies


  In order to check for consistency with the radio-loud AGN unification scheme,
ISOPHOT data obtained for two small sets of intermediate redshift
steep-spectrum 3CR radio galaxies and quasars are being examined. Supplementary
submillimeter and centimeter radio data for the quasars are also taken into
account, in order to assess the magnitude of any beamed nonthermal radiation.
The fact that we find broad-lined objects to be somewhat more luminous in their
far-infrared output than narrow-lined objects, hints at a contradiction to the
unification scheme. However, as the sample objects are not particularly well
matched, the sample size is small, and the FIR radiation may still be partly
anisotropic, this evidence is, at the moment, weak.

</DOC>
<DOC>
<DOCNO> 9447 </DOCNO>
Particle dynamics in sheared granular matter


  The particle dynamics and shear forces of granular matter in a Couette
geometry are determined experimentally. The normalized tangential velocity
$V(y)$ declines strongly with distance $y$ from the moving wall, independent of
the shear rate and of the shear dynamics. Local RMS velocity fluctuations
$\delta V(y)$ scale with the local velocity gradient to the power $0.4 \pm
0.05$. These results agree with a locally Newtonian, continuum model, where the
granular medium is assumed to behave as a liquid with a local temperature
$\delta V(y)^2$ and density dependent viscosity.

</DOC>
<DOC>
<DOCNO> 84303 </DOCNO>
P-brane black holes for general intersections


  Black hole generalized p-brane solutions for a wide class of intersection
rules are presented. The solutions are defined on a manifold that contains a
product of n - 1 Ricci-flat ``internal'' spaces. They are defined up to moduli
functions H_s = H_s(R) obeying a non-linear differential equations (equivalent
to Toda-type equations) with certain boundary conditions imposed. Using
conjecture on polynomial structure of H_s for intersections related to Lie
algebras, new A_2-dyon solutions are obtained. Two examples of these A_2-dyon
solutions, i.e. dyon in D = 11 supergravity with M2 and M5 branes intersecting
at a point and dyon in Kaluza-Klein theory, are considered.

</DOC>
<DOC>
<DOCNO> 101427 </DOCNO>
Prime Type III Factors


  We show that for each (0<\lambda <1), the free Araki-Woods factor of type
III(_{\lambda}) cannot be written as a tensor product of two diffuse von
Neumann algebras (i.e., is prime), and does not contain a Cartan subalgebra.

</DOC>
<DOC>
<DOCNO> 100030 </DOCNO>
On canonically derived families of surfaces of general type over curves


  Suppose X is a smooth projective 3-fold of general type and |mK_X| is
composed of a pencil of surfaces with m>1. This pencil naturally induces a
fibration f:X->C onto a smooth curve C after the Stein-factorization, which is
the main objects of this article. Based on Koll'ar's earlier works, we improve
on it and try to understand the family in terms of discrete birational
invariants of the total space as well as those of the general fiber and the
base curve. The aim of this note is to build a little bit basic facts.

</DOC>
<DOC>
<DOCNO> 100941 </DOCNO>
Clebsch (String) Parameterization of 3-Vectors and Their Actions


  We discuss some properties of the intrinsically nonlinear Clebsch
decomposition of a vector field into three scalars in d=3. In particular, we
note and account for the incompleteness of this parameterization when
attempting to use it in variational principles involving Maxwell and
Chern-Simons actions. Similarities with string decomposition of metrics and
their actions are also pointed out.

</DOC>
<DOC>
<DOCNO> 80836 </DOCNO>
Numerical evidence for monopoles in 3-dimensional Yang-Mills theory


  Recently Anishetty, Majumdar and Sharatchandra have proposed a way of
characterizing topologically non-trivial configurations for 2+1 dimensional
Yang-Mills theory in a local and manifestly gauge invariant manner. In this
paper paper we develop criteria to locate such objects in lattice gauge theory
and find them in numerical simulations.

</DOC>
<DOC>
<DOCNO> 102108 </DOCNO>
Some new identities for Schur functions


  Some new identities for Schur functions are proved. In particular, we settle
in the affirmative a recent conjecture of Ishikawa-Wakayama and solve a problem
raised by Bressoud.

</DOC>
<DOC>
<DOCNO> 102671 </DOCNO>
The Pin Groups in Physics: C, P, and T


  We review the role in physics of the Pin groups, double covers of the full
Lorentz group. Pin(1,3) is to O(1,3) what Spin(1,3) is to SO(1,3). The
existence of two Pin groups offers a classification of fermions based on their
properties under space or time reversal finer than the classification based on
their properties under orientation preserving Lorentz transformations --
provided one can design experiments that distinguish the two types of fermions.
Many promising experimental setups give, for one reason or another, identical
results for both types of fermions. Two notable positive results show that the
existence of two Pin groups is relevant to physics:
  1) In a neutrinoless double beta decay, the neutrino emitted and reabsorbed
in the course of the interaction can only be described in terms of Pin(3,1).
  2) If a space is topologically nontrivial, the vacuum expectation values of
Fermi currents defined on this space can be totally different when described in
terms of Pin(1,3) and Pin(3,1).
  Possibly more important than the two above predictions, the Pin groups
provide a simple framework for the study of fermions; they make possible clear
definitions of intrinsic parities and time reversal. A section on Pin groups in
arbitrary spacetime dimensions is included.

</DOC>
<DOC>
<DOCNO> 83069 </DOCNO>
Bezier Curves Intersection Using Relief Perspective


  Presented paper describes the method for finding the intersection of class
space rational Bezier curves. The problem curve/curve intersection belongs
among basic geometric problems and the aim of this article is to describe the
new technique to solve the problem using relief perspective and Bezier
clipping.

</DOC>
<DOC>
<DOCNO> 11236 </DOCNO>
Depinning Transition of a Two Dimensional Vortex Lattice in a


  We use Monte Carlo simulations of the 2D one component Coulomb gas on a
triangular lattice, to study the depinning transition of a 2D vortex lattice in
a commensurate periodic potential. A detailed finite size scaling analysis
indicates this transition to be first order. No significant changes in behavior
were found as vortex density was varied over a wide range.

</DOC>
<DOC>
<DOCNO> 39730 </DOCNO>
QCD studies with e+e- annihilation data at 172-189 GeV


  We have studied hadronic events from e+e- annihilation data at centre-of-mass
energies of sqrt{s}=172, 183 and 189 GeV. The total integrated luminosity of
the three samples, measured with the OPAL detector, corresponds to 250 pb^-1.
  We present distributions of event shape variables, charged particle
multiplicity and momentum, measured separately in the three data samples. From
these we extract measurements of the strong coupling alpha_s, the mean charged
particle multiplicity <nch> and the peak position xi_0 in the xi_p=ln(1/x_p)
distribution.
  In general the data are described well by analytic QCD calculations and Monte
Carlo models. Our measured values of alpha_s, <nch> and xi_0 are consistent
with previous determinations at sqrt{s}=MZ.

</DOC>
<DOC>
<DOCNO> 12371 </DOCNO>
Electromagnetic field angular momentum in condensed matter systems


  Various electromagnetic systems can carry an angular momentum in their {\bf
E} and {\bf B} fields. The electromagnetic field angular momentum (EMAM) of
these systems can combine with the spin angular momentum to give composite
fermions or composite bosons. In this paper we examine the possiblity that an
EMAM could provide an explanation of the fractional quantum Hall effect (FQHE)
which is complimentary to the Chern-Simons explanation. We also examine a toy
model of a non-BCS superconductor (e.g. high $T_c$ superconductors) in terms of
an EMAM. The models presented give a common, simple picture of these two
systems in terms of an EMAM. The presence of an EMAM in these systems might be
tested through the observation of the decay modes of a charged, spin zero
unstable particle inside one of these systems.

</DOC>
<DOC>
<DOCNO> 13624 </DOCNO>
Quantum Phase Transitions and the Breakdown of Classical General


  It is proposed that the event horizon of a black hole is a quantum phase
transition of the vacuum of space-time analogous to the liquid-vapor critical
point of a bose fluid. The equations of classical general relativity remain
valid arbitrarily close to the horizon yet fail there through the divergence of
a characteristic coherence length. The integrity of global time, required for
conventional quantum mechanics to be defined, is maintained. The metric inside
the event horizon is different from that predicted by classical general
relativity and may be de Sitter space. The deviations from classical behavior
lead to distinct spectroscopic and bolometric signatures that can, in
principle, be observed at large distances from the black hole.

</DOC>
<DOC>
<DOCNO> 150942 </DOCNO>
A Note On Holographic Ward Identities


  In this note we show how Ward identities may be derived for a quantum field
theory dual of a string theory using the AdS/CFT correspondence. In particular
associated with any gauge symmetry of the bulk supergravity theory there is a
corresponding constraint equation. Writing this constraint in Hamilton-Jacobi
form gives a generating functional for Ward identities in the dual QFT. We
illustrate the method by considering various examples.

</DOC>
<DOC>
<DOCNO> 118075 </DOCNO>
Optical and X-ray analysis of the cluster of galaxies Abell 496


  We present a detailed analysis of the cluster of galaxies \a4. The optical
data include a redshift catalogue of 466 galaxies, out of which 274 belong to
the main cluster and a CCD photometric catalogue in a much smaller region, with
239 and 610 galaxies in the V and R bands respectively. The X-ray analysis is
based on an image obtained with the ROSAT PSPC. Besides Abell 496 itself, the
velocity distribution along the line of sight shows the existence of at least
four structures at different redshifts, one of them seeming to be a poor
cluster at a velocity of 30083 km/s. The other of these structures have a too
large spatial extent to be clusters but may be filaments along the line of
sight or other young structures. Various independent methods show that Abell
496 appears to be a quite relaxed cluster, except perhaps for the distribution
of emission line galaxies. These appear to be distributed in two samples
falling on to the main cluster, one from the back (the ELGs concentrated
towards the west) and one from the front (the high velocity ELGs). The bright
part of the galaxy luminosity function, built from the redshift catalogue,
shows a flattening at R$\sim 16$ (M$_{\rm R}\sim -20.5$), and can be accounted
for by a gaussian distribution of bright galaxies and a power law or Schechter
function for faint galaxies. The deeper galaxy counts derived from CCD imaging
show a dip at R$\sim 19.5$ (M$_{\rm R} \sim -17$) which can be modelled
assuming a cut-off in the luminosity function such as that observed in Coma. We
propose a model for the X-ray gas and derive the galaxy, X-ray gas and total
dynamical masses, as well as the baryon fraction in the cluster. \a4 appears as
a relaxed cluster which can be used as a prototype for further studies.

</DOC>
<DOC>
<DOCNO> 14171 </DOCNO>
Hysteresis and Avalanches in the Random Anisotropy Ising Model


  The behaviour of the Random Anisotropy Ising model at T=0 under local
relaxation dynamics is studied. The model includes a dominant ferromagnetic
interaction and assumes an infinite anisotropy at each site along local
anisotropy axes which are randomly aligned. Two different random distributions
of anisotropy axes have been studied. Both are characterized by a parameter
that allows control of the degree of disorder in the system. By using numerical
simulations we analyze the hysteresis loop properties and characterize the
statistical distribution of avalanches occuring during the metastable evolution
of the system driven by an external field. A disorder-induced critical point is
found in which the hysteresis loop changes from displaying a typical
ferromagnetic magnetization jump to a rather smooth loop exhibiting only tiny
avalanches. The critical point is characterized by a set of critical exponents,
which are consistent with the universal values proposed from the study of other
simpler models.

</DOC>
<DOC>
<DOCNO> 9181 </DOCNO>
Topological defect system in O(n) symmetric time-dependent


  We present a new generalized topological current in terms of the order
parameter field $\vec \phi$ to describe the topological defect system in O(n)
symmetric time-dependent Ginzburg-Landau model. With the aid of the $%
\phi$-mapping method, the structure of the topological defects and the
topological quantization of their topological charges in TDGL model are
obtained under the condition that the Jacobian $% J(\frac \phi v)\neq 0$. We
show that the topological defects are generated from the zero points of the
order parameter field $\vec \phi$, and the topological charges of these
topological defects are topological quantized in terms of the Hopf indices and
Brouwer degrees of $\phi$-mapping under the condition. When $J(\frac \phi
v)=0$, it is shown that there exist the crucial case of branch process. Based
on the implicit function theorem and the Taylor expansion, we detail the
bifurcation of generalized topological current and find different directions of
the bifurcation. The topological defects in TDGL model are found splitting or
merging at the degenerate point of field function $\vec \phi $ but the total
charge of the topological defects is still unchanged.

</DOC>
<DOC>
<DOCNO> 9587 </DOCNO>
The Density Matrix Renormalization Group technique with periodic


  The Density Matrix Renormalization Group (DMRG) method with periodic boundary
conditions is introduced for two dimensional classical spin models. It is shown
that this method is more suitable for derivation of the properties of infinite
2D systems than the DMRG with open boundary conditions despite the latter
describes much better strips of finite width. For calculation at criticality,
phenomenological renormalization at finite strips is used together with a
criterion for optimum strip width for a given order of approximation. For this
width the critical temperature of 2D Ising model is estimated with seven-digit
accuracy for not too large order of approximation. Similar precision is reached
for critical indices. These results exceed the accuracy of similar calculations
for DMRG with open boundary conditions by several orders of magnitude.

</DOC>
<DOC>
<DOCNO> 169712 </DOCNO>
Rules for Integrals over Products of Distributions from Coordinate


  In perturbative calculations of quantum mechanical path integrals in
curvilinear coordinates, Feynman diagrams involve multiple temporal integrals
over products of distributions, which are mathematically undefined. We derive
simple rules for their evaluation from the requirement of coordinate
independence of path integrals.

</DOC>
<DOC>
<DOCNO> 116791 </DOCNO>
Threshold amplitudes for transition to turbulence in a pipe


  Although flow in a circular pipe is stable to infinitesimal perturbations, it
can be excited to turbulence by finite perturbations whose minimal amplitude
shrinks as R goes to infinity (R = Reynolds number). Laboratory experiments
have appeared to disagree with one another and with theoretical predictions
about the dependence of this minimal amplitude on $R$, with published results
ranging approximately from $R^{-1/4}$ to $R^{-3/2}$. Here it is shown that
these discrepancies can be explained by the use of different definitions of
amplitude by different authors. An attempt is made to convert the existing
results to a uniform definition of amplitude, the nondimensionalized $L^2$
definition common in the theoretical literature. Although subtleties in the
physics raise some questions, agreement appears to be reached on a minimal
amplitude that scales as $R^{-3/2 \pm 0.3}$.

</DOC>
<DOC>
<DOCNO> 122248 </DOCNO>
The European Large Area ISO Survey IV: the preliminary 90 micron


  We present the luminosity function of 90um selected galaxies from the
European Large Area ISO Survey (ELAIS), extending to z=0.3. Their luminosities
are in the range 10^9 < h_65^-2 L/Lsun < 10^12, i.e. non-ultraluminous. From
our sample of 37 reliably detected galaxies in the ELAIS S1 region from the
Efstathiou et al. (2000) S_90 >= 100mJy database, we found optical, 15um or
1.4GHz identifications for 24 (65%). We have obtained 2dF and UK Schmidt FLAIR
spectroscopy of 89% of IDs to rigid multivariate flux limits. We construct a
luminosity function assuming (a) our spectroscopic subset is an unbiased sparse
sample, and (b) there are no galaxies which would not be represented in our
spectroscopic sample at {\it any} redshift. We argue that we can be confident
of both assumptions. We find the luminosity function is well-described by the
local 100um luminosity function of Rowan-Robinson, Helou & Walker (1987). {\it
Assuming} this local normalisation, we derive luminosity evolution of
(1+z)^{2.45\pm0.85} (95% confidence). We argue that star formation dominates
the bolometric luminosities of these galaxies and we derive comoving star
formation rates in broad agreement with the Flores et al. (1999) and
Rowan-Robinson et al. (1997) mid-IR-based estimates.

</DOC>
<DOC>
<DOCNO> 152375 </DOCNO>
Randall-Sundrum Brane Tensions


  We show that the singular sources in the energy-momentum tensor for the
Randall-Sundrum brane world, viewed as a solution of type IIB supergravity, are
composed of two elements. One of these is a D3-brane source with tension
opposite in sign to the RS tension in five dimensions; the other arises from
patching two regions of flat ten-dimensional spacetime. This resolves an
apparent discrepancy between supersymmetry and the sign and magnitude of the RS
tension.

</DOC>
<DOC>
<DOCNO> 122571 </DOCNO>
Time dependent cosmic-ray shock acceleration with self-consistent


  One of the key questions to understanding the efficiency of diffusive shock
acceleration of the cosmic rays (CRs) is the injection process from thermal
particles. A self-consistent injection model based on the interactions of the
suprathermal particles with self-generated magneto-hydrodynamic waves has been
developed recently by Malkov (1998, Phys. Rev. E 58, 4911). By adopting this
analytic solution, a numerical treatment of the plasma-physical injection model
at a strong quasi-parallel shock has been devised and incorporated into the
combined gas dynamics and the CR diffusion-convection code. In order to
investigate self-consistently the injection and acceleration efficiencies, we
have applied this code to the CR modified shocks of both high and low Mach
numbers (M=30 and M=2.24) with a Bohm type diffusion model. We find the
injection process is self-regulated in such a way that the injection rate
reaches and stays at a nearly stable value after quick initial adjustment. For
both shocks about 0.1% of the incoming thermal particles are injected into the
CRs. For the weak shock, the shock has reached a steady state within our
integration time and about 10% of the total available shock energy is
transfered into the CR energy density. The strong shock has achieved a higher
acceleration efficiency of about 20% by the end of our simulation, but has not
yet reached a steady-state.

</DOC>
<DOC>
<DOCNO> 69690 </DOCNO>
A note on dynamical stabilization of internal spaces in multidimensional


  The possibility of dynamical stabilization of an internal space is
investigated for a multidimensional cosmological model with minimal coupled
scalar field as inflaton. It is shown that a successful dynamical
compactification crucially depends on the type of interaction between the
geometrical modulus field and the inflaton and its decay products. In the
considered model a stable compactification can be ensured via trapping of the
modulus field by a minimum of the effective potential.

</DOC>
<DOC>
<DOCNO> 8139 </DOCNO>
Depolarisation of spherical-membrane quantum well: Gap renormalisation


  An anomalous large level shift is newly found to correct the one-electron
spectrum of a closed-shell carbon nanocluster, for example, the spectrum which
was described within the model of a thin quantum well rolled into a sphere. As
a result of the interaction with zero-point oscillations of the confined modes
of the electric field, the one-electron energy levels heighten. The
depolarization depends on the electron momentum, why it does not shift the
rotational spectrum as a whole. Surprisingly the shift in a spherical
closed-shell cluster of an arbitrary size is described by an universal law.
The non-equidistant shift of the levels results in an increase of an
one-electron gap by 1.4 times.

</DOC>
<DOC>
<DOCNO> 9405 </DOCNO>
Local functional models of critical correlations in thin-films


  Recent work on local functional theories of critical inhomogeneous fluids and
Ising-like magnets has shown them to be a potentially exact, or near exact,
description of universal finite-size effects associated with the excess
free-energy and scaling of one-point functions in critical thin films. This
approach is extended to predict the two-point correlation function G in
critical thin-films with symmetric surface fields in arbitrary dimension d. In
d=2 we show there is exact agreement with the predictions of conformal
invariance for the complete spectrum of correlation lengths as well as the
detailed position dependence of the asymptotic decay of G. In d=3 and d>=4 we
present new numerical predictions for the universal finite-size correlation
length and scaling functions determining the structure of G across the
thin-film. Highly accurate analytical closed form expressions for these
universal properties are derived in arbitrary dimension.

</DOC>
<DOC>
<DOCNO> 152359 </DOCNO>
The Lax pairs for elliptic C_n and BC_n Ruijsenaars-Schneider models and


  We study the elliptic C_n and BC_n Ruijsenaars-Schneider models which is
elliptic generalization of system given in hep-th/0006004. The Lax pairs for
these models are constructed by Hamiltonian reduction technology. We show that
the spectral curves can be parameterized by the involutive integrals of motion
for these models. Taking nonrelativistic limit and scaling limit, we verify
that they lead to the systems corresponding to Calogero-Moser and Toda types.

</DOC>
<DOC>
<DOCNO> 117884 </DOCNO>
Analytic solutions for coupled linear perturbations


  Analytic solutions for the evolution of cosmological linear density
perturbations in the baryonic gas and collisionless dark matter are derived.
The solutions are expressed in a closed form in terms of elementary functions,
for arbitrary baryonic mass fraction. They are obtained assuming $\Omega=1$ and
a time independent comoving Jeans wavenumber, $k_J$. By working with a time
variable $\tau\equiv \ln(t^{2/3})$, the evolution of the perturbations is
described by linear differential equations with constant coefficients. The new
equations are then solved by means of Laplace transformation assuming that the
gas and dark matter trace the same density field before a sudden heating epoch.
In a dark matter dominated Universe, the ratio of baryonic to dark matter
density perturbation decays with time roughly like $\exp(-5\tau/4)\propto
t^{-5/6}$ to the limiting value $1/[1+(k/k_J)^2]$. For wavenumbers
$k>k_J/\sqrt{24}$, the decay is accompanied with oscillations of a period $
8\pi/\sqrt{24 (k/k_J)^2 -1}$ in $\tau$. In comparison, as $\tau $ increases in
a baryonic matter dominated Universe, the ratio approaches $1-(k/k_J)^2$ for
$k\le k_J$, and zero otherwise.

</DOC>
<DOC>
<DOCNO> 118527 </DOCNO>
Very-high-energy gamma radiation associated with the unshocked wind of


  We show that the relativistic wind in the Crab pulsar, which is commonly
thought to be invisible in the region upstream of the termination shock at R <
0.1 pc, in fact could be directly observed through its inverse Compton gamm-ray
emission. The search for such specific component of radiation in the gamma-ray
spectrum of the Crab can provide unique information about the unshocked pulsar
wind that is not accessible at other wavelengths.

</DOC>
<DOC>
<DOCNO> 170281 </DOCNO>
The Classical Limit of Quantum Mechanics and the Fejer Sum of the


  In quantum mechanics, the expectation value of a quantity on a quantum state,
provided that the state itself gives in the classical limit a motion of a
particle in a definite path, in classical limit goes over to Fourier series
form of the classical quantity. In contrast to this widely accepted point of
view, a rigorous calculation shows that the expectation value on such a state
in classical limit exactly gives the Fej\'{e}r's arithmetic mean of the partial
sums of the Fourier series.

</DOC>
<DOC>
<DOCNO> 14127 </DOCNO>
The polaron confined in one dimension


  The ground-state energy, the effective mass and the number of virtual phonons
of the optical large polaron confined strictly in one dimension have been
estimated by using the generalized Gaussian approximation. The leading-order
terms take care of all Gaussian fluctuations in the system and improve the
conventional variational estimates at finite coupling. Particularly, the lowest
upper bound to the polaron ground-state energy has been obtained. The
non-Gaussian contributions systematically correct the leading-order
approximations. We have obtained exact analytical solutions in the weak- and
strong-coupling limit and reasonable numerical data for intermediate coupling.
Our result for the number of excited phonons limits the validity region of the
few-phonon approximation methods.

</DOC>
<DOC>
<DOCNO> 11280 </DOCNO>
Transition Temperature for Weakly Interacting Homogeneous Bose Gases


  We apply the non-perturbative optimized linear $\delta$ expansion method to
the O(N) scalar field model in three-dimensions to determine the transition
temperature of a dilute homogeneous Bose gas. Our results show that the shift
of the transition temperature, $\Delta T_c/T_c$, of the interacting model,
compared with the ideal gas transition temperature, really behaves as $\gamma a
n^{1/3}$ where $a$ is the s-wave scattering length and $n$ is the number
density. For $N= 2$ our calculations yield the value $\gamma= 3.059$.

</DOC>
<DOC>
<DOCNO> 100177 </DOCNO>
Isoparametric submanifolds and a Chevalley-type restriction theorem


  We define and study isoparametric submanifolds of general ambient spaces and
of arbitrary codimension. In particular we study their behaviour with respect
to Riemannian submersions and their lift into a Hilbert space. These results
are used to prove a Chevalley type restriction theorem which relates by
restriction eigenfunctions of the Laplacian on a compact Riemannian manifold
which contains an isoparametric submanifold with flat sections to
eigenfunctions of the Laplacian of a section. A simple example of such an
isoparametric foliation is given by the conjugacy classes of a compact Lie
group and in that case the restriction theorem is a (well known) fundamental
result in representation theory. As an application of the restriction theorem
we show that isoparametric submanifolds with flat sections in compact symmetric
spaces are level sets of eigenfunctions of the Laplacian and are hence related
to representation theory. In addition we also get the following results.
Isoparametric submanifolds in Hilbert space have globally flat normal bundle,
and a general result about Riemannian submersions which says that focal
distances do not change if a submanifold of the base is lifted to the total
space.

</DOC>
<DOC>
<DOCNO> 152139 </DOCNO>
Supergravity Instantons for N=2 Hypermultiplets


  The dimensional reduction of eleven dimensional supergravity on a Calabi-Yau
manifold gives N=2 supergravity in five dimensions with $h_{1,1}$ vector and
$h_{2,1}+1$ hypermultiplets. In this paper instanton solutions are constructed
which are responsible for nonperturbtative corrections to the hypermultiplet
moduli spaces. These instantons are wrapped Euclidean membranes and fivebranes.
For vanishing fivebrane charge the BPS conditions for these solutions define a
flow in the hypermultiplet moduli space and are isomorphic to the attractor
equations for four dimensional black holes.

</DOC>
<DOC>
<DOCNO> 9612 </DOCNO>
Coherent backscattering effect on wave dynamics in a random medium


  A dynamical effect of coherent backscattering is predicted theoretically and
supported by computer simulations: The distribution of single-mode delay times
of waves reflected by a disordered waveguide depends on whether the incident
and detected modes are the same or not. The change amounts to a rescaling of
the distribution by a factor close to $\sqrt{2}$. This effect appears only if
the length of the waveguide exceeds the localization length; there is no effect
of coherent backscattering on the delay times in the diffusive regime.

</DOC>
<DOC>
<DOCNO> 120032 </DOCNO>
A Relationship Between Nuclear Black Hole Mass and Galaxy Velocity


  We describe a correlation between the mass M_BH of a galaxy's central black
hole and the luminosity-weighted line-of-sight velocity dispersion sigma_e
within the half-light radius. The result is based on a sample of 26 galaxies,
including 13 galaxies with new determinations of black hole masses from Hubble
Space Telescope measurements of stellar kinematics. The best-fit correlation is
M_BH = 1.2 (+-0.2) x 10^8 M_sun (sigma_e/200 km/s)^(3.75 (+-0.3))over almost
three orders of magnitude in M_BH; the scatter in M_BH at fixed sigma_e is only
0.30 dex and most of this is due to observational errors. The M_BH-sigma_e
relation is of interest not only for its strong predictive power but also
because it implies that central black hole mass is constrained by and closely
related to properties of the host galaxy's bulge.

</DOC>
<DOC>
<DOCNO> 170765 </DOCNO>
Bibliographic guide to the foundations of quantum mechanics and quantum


  This is a collection of references (papers, books, preprints, book reviews,
Ph. D. thesis, patents, etc.), sorted alphabetically and (some of them)
classified by subject, on foundations of quantum mechanics and quantum
information. Specifically, it covers hidden variables (``no-go'' theorems,
experiments), interpretations of quantum mechanics, entanglement, quantum
effects (quantum Zeno effect, quantum erasure, ``interaction-free''
measurements, quantum ``non-demolition'' measurements), quantum information
(cryptography, cloning, dense coding, teleportation), and quantum computation.

</DOC>
<DOC>
<DOCNO> 116431 </DOCNO>
Hierarchic Theory Of Condensed Matter: New state equation and


  1. The state equation for real gas 2. New state equation for condensed matter
3.Vapor pressure 4. Surface tension 5. Mesoscopic theory of thermal
conductivity 6. Mesoscopic theory of viscosity for liquids and solids 7.
Brownian diffusion 8. Self-diffusion in liquids and solids 9. Mesoscopic
approach to proton conductivity in water, ice and other systems, containing
hydrogen bonds 10. Regulation of pH and shining of water by electromagnetic and
acoustic fields

</DOC>
<DOC>
<DOCNO> 70986 </DOCNO>
General analysis of lepton polarizations in rare B -> K^* l^+ l^- decay


  The general analysis of lepton polarization asymmetries in rare B -> K^* l^+
l^- decay is investigated. Using the most general, model independent effective
Hamiltonian, the general expressions of the longitudinal, normal and
transversal polarization asymmetries for l^- and l^+ and combinations of them
are presented. The dependence of lepton polarizations and their combinations on
new Wilson coefficients are studied in detail. Our analysis shows that the
lepton polarization asymmetries are very sensitive to the scalar and tensor
type interactions, which will be very useful in looking for new physics beyond
the standard model.

</DOC>
<DOC>
<DOCNO> 8711 </DOCNO>
Three-dimensional vortex dynamics in Bose-Einstein condensates


  We simulate in the mean-field limit the effects of rotationally stirring a
three-dimensional trapped Bose-Einstein condensate with a Gaussian laser beam.
A single vortex cycling regime is found for a range of trap geometries, and is
well described as coherent cycling between the ground and the first excited
vortex states. The critical angular speed of stirring for vortex formation is
quantitatively predicted by a simple model. We report preliminary results for
the collisions of vortex lines, in which sections may be exchanged.

</DOC>
<DOC>
<DOCNO> 70804 </DOCNO>
Puzzling aspects of hot quantum fields


  Over the past decade, Finite Temperature Quantum Field Theories have
benefitted from impressive developments, while an increasing number of
intriguing points were made. Some of them are presented here, recent and older,
in a non exhaustive list.

</DOC>
<DOC>
<DOCNO> 122462 </DOCNO>
The M31 Globular Cluster Luminosity Function


  We combine our compilation of photometry of M31 globular cluster and probable
cluster candidates with new near-infrared photometry for 30 objects. Using
these data we determine the globular cluster luminosity function (GCLF) in
multiple filters for the M31 halo clusters. We find a GCLF peak and dispersion
of V_0^0=16.84 +/-0.11, sigma_t=0.93 +/- 0.13 (Gaussian sigma = 1.20 +/- 0.14),
consistent with previous results. The halo GCLF peak colors (e.g., B^0_0 -
V^0_0) are consistent with the average cluster colors. We also measure V-band
GCLF parameters for several other subsamples of the M31 globular cluster
population. The inner third of the clusters have a GCLF peak significantly
brigher than that of the outer clusters (delta V =~ 0.5mag). Dividing the
sample by both galacticentric distance and metallicity, we find that the GCLF
also varies with metallicity, as the metal-poor clusters are on average 0.36
mag fainter than the metal-rich clusters. Our modeling of the catalog selection
effects suggests that they are not the cause of the measured differences, but a
more complete, less-contaminated M31 cluster catalog is required for
confirmation. Our results imply that dynamical destruction is not the only
factor causing variation in the M31 GCLF: metallicity, age, and cluster initial
mass function may also be important.

</DOC>
<DOC>
<DOCNO> 122717 </DOCNO>
The Butcher-Oemler Effect in 295 Clusters: Strong Redshift Evolution and


  We examine the Butcher-Oemler effect and its cluster richness dependence in
the largest sample studied to date: 295 Abell clusters. We find a strong
correlation between cluster richness and the fraction of blue galaxies, f_B, at
every redshift. The slope of the f_B(z) relation is similar for all richnesses,
but at a given redshift, f_B is systematically higher for poor clusters. This
is the chief cause of scatter in the f_B vs. z diagram: the spread caused by
the richness dependence is comparable to the trend in f_B over a typical
redshift baseline, so that conclusions drawn from smaller samples have varied
widely. The two parameters, z, and a consistently defined projected galaxy
number density, N, together account for all of the observed variation in f_B
within the measurement errors. The redshift evolution of f_B is real, and
occurs at approximately the same rate for clusters of all richness classes.

</DOC>
<DOC>
<DOCNO> 174460 </DOCNO>
Quasi-free Compton Scattering from the Deuteron and Nucleon


  Cross sections for quasi-free Compton scattering from the deuteron were
measured for incident energies of 236--260 MeV at the laboratory angle -135
degrees. The recoil nucleons were detected in a liquid-scintillator array
situated at 20 degrees. The measured differential cross sections were used,
with the calculations of Levchuk et al., to determine the polarizabilities of
the bound nucleons. For the bound proton, the extracted values were consistent
with the accepted value for the free proton. Combining our results for the
bound neutron with those from Rose et al., we obtain one-sigma constraints of
alpha_n = 7.6-14.0 and beta_n = 1.2-7.6.

</DOC>
<DOC>
<DOCNO> 122052 </DOCNO>
Determining gravitational lensing effects on supernovae observations


  In this paper we use a generalized version of a method originally proposed by
Holz and Wald to investigate the effects from gravitational lensing on Type Ia
supernovae measurements. We find that results for different mass distributions
in smooth dark matter halos are very similar, making lensing effects
predictable for a broad range of density profiles. Also, a sample of 100
supernovae at z = 1, should be sufficient to discriminate between the case of
all dark matter in smooth halos and the extreme case of all dark matter in
point-like objects.

</DOC>
<DOC>
<DOCNO> 117266 </DOCNO>
Complex Scaling of the Faddeev Equations


  In this work we compare two different approaches to calculation of the
three-body resonances on the basis of Faddeev differential equations. The first
one is the complex scaling approach. The second method is based on an immediate
calculation of resonances as zeros of the three-body scattering matrix
continued to the physical sheet.

</DOC>
<DOC>
<DOCNO> 119103 </DOCNO>
Non-pulsed emission from the binary system PSR B1259-63


  PSR B1259-63 is the only known binary system with a radio pulsar from which
the non-pulsed radio and X-ray emission was detected. The companion star in
this system is a Be star SS 2883. A rapidly rotating radio pulsar is expected
to produce a wind of relativistic particles. Be stars are known to produce
highly asymmetric mass loss. Due to the interaction of the pulsar wind and the
Be star wind the system of two shocks between the pulsar and the Be star forms.
In this paper we show that the observed non-pulsed radio emission from the
system is a result of the synchrotron emission of the relativistic particles in
the outflow beyond the shock wave and that the non-pulsed X-ray emission is due
to the inverse Compton scattering of the Be star photons on this particles.

</DOC>
<DOC>
<DOCNO> 10438 </DOCNO>
Thermodynamic properties of confined interacting Bose gases - a


  A renormalization group method is developed with which thermodynamic
properties of a weakly interacting, confined Bose gas can be investigated.
Thereby effects originating from a confining potential are taken into account
by periodic boundary conditions and by treating the resulting discrete energy
levels of the confined degrees of freedom properly. The resulting density of
states modifies the flow equations of the renormalization group in momentum
space. It is shown that as soon as the characteristic length of confinement
becomes comparable to the thermal wave length of a weakly interacting and
trapped Bose gas its thermodynamic properties are changed significantly. This
is exemplified by investigating characteristic bunching properties of the
interacting Bose gas which manifest themselves in the second order coherence
factor.

</DOC>
<DOC>
<DOCNO> 10538 </DOCNO>
Interfacial fluctuations near the critical filling transition


  We propose a method to describe the short-distance behavior of an interface
fluctuating in the presence of the wedge-shaped substrate near the critical
filling transition. Two different length scales determined by the average
height of the interface at the wedge center can be identified. On one length
scale the one-dimensional approximation of Parry et al. \cite{Parry} which
allows to find the interfacial critical exponents is extracted from the full
description. On the other scale the short-distance fluctuations are analyzed by
the mean-field theory.

</DOC>
<DOC>
<DOCNO> 122041 </DOCNO>
Chemical Evolution of the Stellar and Gaseous Components of Galaxies in


  We present preliminary results on the effects of mergers on the chemical
properties of galactic objects in hierarchical clustering scenarios. We adopt a
hydrodynamical chemical code that allows to describe the coupled evolution of
dark matter and baryons within a cosmological context. We found that disk-like
and spheroid-like objects have distinctive metallicity patterns that may be the
result of different evolution.

</DOC>
<DOC>
<DOCNO> 70701 </DOCNO>
A Model of the Electroweak Interactions with Invisible Higgs Particle


  We propose a minimal unified model of the electroweak interactions without a
Higgs particle in the final physical spectrum. This is achieved through adding
a nonlinear constraint for the Higgs field in the Lagrangian in which the
field's content is the same as in the Weinberg-Salam (WS) model. In the unitary
gauge the generation of masses of the $W^{\pm}$ and $Z$ bosons, as well as for
the leptons and quarks, reproduces the known pattern in the WS model. The path
integral quantization shows that with the exception of the scalar particles'
all other vertices, known from the WS model in the unitary gauge, remain. A
Ward identity relative to the electromagnetic gauge group is also derived.

</DOC>
<DOC>
<DOCNO> 13803 </DOCNO>
Trimer-Monomer Mixture Problem on (111) $1 \times 1$ Surface of Diamond


  We consider a system of trimers and monomers on the triangular lattice, which
describes the adsorption problem on (111) $1 \times 1$ surface of diamond
structure. We give a mapping to a 3-state vertex model on the square lattice.
We treat the problem by the transfer-matrix method combined with the
density-matrix algorithm, to obtain thermodynamic quantities.

</DOC>
<DOC>
<DOCNO> 8691 </DOCNO>
Analytic Theory of Fractal Growth Patterns in 2 Dimensions


  Diffusion Limited Aggregation (DLA) is a model of fractal growth that was
introduced in 1981 and had since attained a paradigmatic status due to its
simplicity and its underlying role for a variety of pattern forming processes.
Despite tremendous efforts there is no theory to compute the fractal dimension
of DLA from first principles. In this Letter we offer such a theory for fractal
growth patterns in two dimensions, including DLA as a particular case. In this
theory the fractal dimension of the asymptotic cluster manifests iteself as a
renormalization exponent observable already at very early growth stages. Using
early stage dynamics we compute 1.6896<D<1.7135, and explain why traditional
numerical estimates converged so slowly. We discuss similar computations for
other fractal growth processes in 2-dimensions.

</DOC>
<DOC>
<DOCNO> 13105 </DOCNO>
Ladder operator for the one-dimensional Hubbard model


  The one-dimensional Hubbard model is integrable in the sense that it has an
infinite family of conserved currents. We explicitly construct a ladder
operator which can be used to iteratively generate all of the conserved current
operators. This construction is different from that used for Lorentz invariant
systems such as the Heisenberg model. The Hubbard model is not Lorentz
invariant, due to the separation of spin and charge excitations. The ladder
operator is obtained by a very general formalism which is applicable to any
model that can be derived from a solution of the Yang-Baxter equation.

</DOC>
<DOC>
<DOCNO> 71082 </DOCNO>
Generalized Parton Distributions and the Dependence of Parton


  Generalized parton distributions (GPDs) provide a link between form factors,
parton distributions and other observables. I discuss the connection between
GPDs and parton distributions as a function of the impact parameter. Since this
connection involves GPDs in the limit of vanishing skewedness parameter $\xi$,
i.e. when the off-forwardness is purely transverse, I also illustrate how to
relate $\xi\neq 0$ data to $\xi=0$ data, which is important for experimental
measurements of these observables.

</DOC>
<DOC>
<DOCNO> 100274 </DOCNO>
New non-unitary representations in a Dirac hydrogen atom


  New non-unitary representations of the SU(2) algebra are introduced for the
case of the Dirac equation with a Coulomb potential; an extra phase, needed to
close the algebra, is also introduced. The new representations does not require
integer or half integer labels. The set of operators defined are used to span
the complete space of bound state eigenstates of the problem thus solving it in
an essentially algebraic way.

</DOC>
<DOC>
<DOCNO> 80719 </DOCNO>
The Critical Mass of Wilson Fermions: A Comparison of Perturbative and


  We calculate the critical value of the hopping parameter, $\kappa_c$, in
Lattice QCD with Wilson fermions, to two loops in perturbation theory.
   This quantity is an additive renormalization; as such, it is characterized
not only by the standard caveats regarding the asymptotic nature of
perturbative results, but also by a linear divergence in the lattice spacing.
Consequently, our calculation tests rather stringently the limits of
applicability of perturbation theory.
   We compare our results to non perturbative evaluations of $\kappa_c$ coming
from Monte Carlo simulations.
   Finally, we apply a tadpole improvement technique on our results; this
shifts them quite favourably towards the non perturbative values.

</DOC>
<DOC>
<DOCNO> 69295 </DOCNO>
Brane-World Cosmology of Modulus Stabilization with a Bulk Scalar Field


  We point out that the potential of Goldberger and Wise for stabilizing the
distance between two 3-branes, separated from each other along an extra
dimension with a warp factor, has a metastable minimum when the branes are
infinitely separated. The classical evolution of the radion (brane separation)
will place it in this false minimum for generic initial conditions. In
particular, inflation could do this if the expansion rate is sufficiently
large. We present a simplified version of the Goldberger-Wise mechanism in
which the radion potential can be computed exactly, and we calculate the rate
of thermal transitions to the true minimum, showing that model parameters can
be chosen to ensure that the universe reaches the desired final state.
Finiteness of bulk scalar field brane potentials can have an important impact
on the nucleation rate, and it can also significantly increase the predicted
mass of the radion.

</DOC>
<DOC>
<DOCNO> 117783 </DOCNO>
On the absence of winds in ADAFs


  We show that recently published assertions that advection dominated accretion
flows (ADAFs) require the presence of strong winds are unfounded because they
assume that low radiative efficiency in flows accreting at low rates onto black
holes implies vanishing radial energy and angular momentum fluxes through the
flow (which is also formulated in terms of the `Bernoulli function' being
positive). This, however, is a property only of self-similar solutions which
are an inadequate representation of global accretion flows. We recall general
properties of accretion flows onto black holes and show that such, necessarily
transonic, flows may have either positive or negative Bernoulli function
depending on the flow viscosity. Flows with low viscosities (alpha<0.1 in the
alpha-viscosity model) have a negative Bernoulli function. Without exception,
all 2-D and 1-D numerical models of low viscosity flows constructed to date
experience no significant outflows. At high viscosities the presence of
outflows depends on the assumed viscosity, the equation of state and on the
outer boundary condition. The positive sign of the Bernoulli function invoked
in this context is irrelevant to the presence of outflows. As an illustration,
we recall 2-D numerical models with moderate viscosity that have positive
values of the Bernoulli function and experience no outflows. ADAFs, therefore,
do not differ from this point of view from thin Keplerian discs: they may have,
but they do not have to have strong winds.

</DOC>
<DOC>
<DOCNO> 7676 </DOCNO>
The strain energy and Young's Moduli of single-wall Carbon nanotubules


  The strain energies in straight and bent single-walled carbon nanotubes
(SWNTs) are calculated by taking account of the total energy of all the
occupied band electrons. The obtained results are in good agreement with
previous theoretical studies and experimental observations. The Young's modulus
and the effective wall thickness of SWNT are obtained from the bending strain
energies of SWNTs with various cross-sectional radii. The repulsion potential
between ions contributes the main part of the Young's modulus of SWNT.
 The wall thickness of SWNT comes completely from the overlap of electronic
orbits, and is approximately of the extension of
 $\pi$ orbit of carbon atom. Both the Young's modulus and the wall thickness
are independent of the radius and the helicity of SWNT, and insensitive to the
fitting parameters.
 The results show that continuum elasticity theory can serve well to describe
the mechanical properties of SWNTs.

</DOC>
<DOC>
<DOCNO> 12225 </DOCNO>
Microscopic theory of the two-dimensional quantum antiferromagnet in a


  We have developed a consistent theory of the Heisenberg quantum
antiferromagnet in the disordered phase with a short range antiferromagnetic
order on the basis of the path integral for spin coherent states. We have
presented the Lagrangian of the theory in a form which is explicitly invariant
under rotations and found natural variables in terms of which one can construct
a natural perturbation theory. The short wave spin fluctuations are similar to
those in the spin wave theory and they are of the order of the parameter $1/2s$
where $s$ is the spin magnitude. The long wave spin fluctuations are governed
by the nonlinear sigma model and are of the order of the the parameter 1/N,
where $N$ is the number of field components. We also have shown that the short
wave spin fluctuations must be evaluated accurately and the continuum limit in
time of the path integral must be performed after all summation over the
frequencies $\omega$. In the framework of our approach we have obtained the
response function for the spin fluctuations for all region of the frequency
$\omega$ and the wave vector ${\bf k}$ and have calculated the free energy of
the system. We have also reproduced the known results for the spin correlation
length in the lowest order in 1/N.

</DOC>
<DOC>
<DOCNO> 151497 </DOCNO>
Relativistic scalar Aharonov-Bohm scattering


  We discuss the scattering of relativistic spin zero particles by an
infinitely long and arbitrarily thin solenoid. The exact solution of the
first-quantized problem can be obtained as a mimic of the nonrelativistic case,
either in the original Aharonov-Bohm way or by using the Berry's magnetization
scheme. The perturbative treatment is developed in the Feshbach-Villars
two-component formalism for the Klein-Gordon equation and it is shown that it
also requires renormalization as in the Schrodinger counterpart. The results
are compared with those of the field theoretical approach which corresponds to
the two-body sector of the scalar Chern-Simons theory.

</DOC>
<DOC>
<DOCNO> 150539 </DOCNO>
The $\nu \nu \gamma$ Amplitude in an External Homogeneous


  Neutrino-photon interactions in the presence of an external homogeneous
constant electromagnetic field are studied. The $\nu \nu \gamma $ amplitude is
calculated in an electromagnetic field of the general type, when the two field
invariants are nonzero.

</DOC>
<DOC>
<DOCNO> 169784 </DOCNO>
Bell's Theorem and Nonlinear Systems


  For all Einstein-Podolsky-Rosen-type experiments on deterministic systems the
Bell inequality holds, unless non-local interactions exist between certain
parts of the setup. Here we show that in nonlinear systems the Bell inequality
can be violated by non-local effects that are arbitrarily weak. Then we show
that the quantum result of the existing Einstein-Podolsky-Rosen-type
experiments can be reproduced within deterministic models that include
arbitrarily weak non-local effects.

</DOC>
<DOC>
<DOCNO> 102124 </DOCNO>
Star Products on Coadjoint Orbits


  We study properties of a family of algebraic star products defined on
coadjoint orbits of semisimple Lie groups. We connect this description with the
point of view of differentiable deformations and geometric quantization.

</DOC>
<DOC>
<DOCNO> 170015 </DOCNO>
Minimal Irreversible Quantum Mechanics: An Axiomatic Formalism


  An axiomatic formalism for a minimal irreversible quantum mechanics is
introduced. It is shown that a quantum equilibrium and the decoherence
phenomenon are consequences of the axioms and that Lyapunov variables,
exponential survival probabilities, and a classisal conditional
never-decreasing entropy can be defined.

</DOC>
<DOC>
<DOCNO> 8867 </DOCNO>
Toy model for the mean-field theory of hard-sphere liquids


  We investigate a toy model of liquid, based on simplified HNC equations in
very large spatial dimension D. The model does not exhibit a phase transition,
but several regimes of the behavior when D\to\infty can be observed in
different intervals of the density.

</DOC>
<DOC>
<DOCNO> 12604 </DOCNO>
Glass transition and layering effects in confined water: a computer


  Single particle dynamics of water confined in a nanopore is studied through
Computer Molecular Dynamics. The pore is modeled to represent the average
properties of a pore of Vycor glass. Dynamics is analyzed at different
hydration levels and upon supercooling. At all hydration levels and all
temperatures investigated a layering effect is observed due to the strong
hydrophilicity of the substrate. The time density correlators show, already at
ambient temperature, strong deviations from the Debye and the stretched
exponential behavior. Both on decreasing hydration level and upon supercooling
we find features that can be related to the cage effect typical of a
supercooled liquid undergoing a kinetic glass transition. Nonetheless the
behavior predicted by Mode Coupling Theory can be observed only by carrying out
a proper shell analysis of the density correlators. Water molecules within the
first two layers from the substrate are in a glassy state already at ambient
temperature (bound water). The remaining subset of molecules (free water)
undergoes a kinetic glass transition; the relaxation of the density correlators
agree with the main predictions of the theory. From our data we can predict the
temperature of structural arrest of free water.

</DOC>
<DOC>
<DOCNO> 150379 </DOCNO>
Possible instability of the vacuum in a strong magnetic field


  The possibility that a static magnetic field may decay through production of
electron positron pairs is studied. The conclusion is that this decay cannot
happen through production of single pairs, as in the electric case, but only
through the production of a many-body state, since the mutual magnetic
interactions of the created pairs play a relevant role. The investigation is
made in view of the proposed existence of huge magnetic field strengths around
some kind of neutron stars.

</DOC>
<DOC>
<DOCNO> 70964 </DOCNO>
Improved SUSY QCD corrections to Higgs boson decays into quarks and


  The O(alpha_s) SUSY QCD corrections to the decays of the MSSM Higgs bosons
into bottom quarks and squarks can be very large for large tan beta in the
on--shell renormalization scheme. We improve the calculation by a careful
choice of the tree-level Higgs boson couplings in terms of running parameters
of quarks and squarks.

</DOC>
<DOC>
<DOCNO> 120182 </DOCNO>
Further Adventures: Oxygen Burning in a Convective Shell


  Two dimensional hydrodynamical simulations of convective oxygen burning shell
in the presupernova evolution of a 20 solar-mass star are extended to later
times. We used the VULCAN code to simulate longer evolution times than
previously possible. Our results confirm the previous work of Bazan and Arnett
(98) over their time span of 400s. However, at 1200s, we could identify a new
steady state that is significantly different than the original one dimensional
model. There is considerable overshooting at both the top and bottom boundaries
of convection zone. Beyond the boundaries, the convective velocity falls off
exponentially, with excitation of internal modes. The resulting mixing greatly
affect the evolution of the simulations. Connections with other works of
simulation of convection, in which such behavior is found in a different
context, are discussed.

</DOC>
<DOC>
<DOCNO> 120562 </DOCNO>
Cyclotron Line Features from Near-Critical Fields II: on the Effect of


  We assess the impact of radiation anisotropy on the line shapes that result
from relativistic magnetic Compton scattering in the low-density/high-field
regime. A Monte Carlo implementation of radiation transport allows for spatial
diffusion of photons in arbitrary geometries and accounts for relativistic
angular redistribution. The cross section includes natural line widths and
photon "spawning" from up to fourth harmonic photons. In our first paper we
noted that even if the photon injection is isotropic a strongly anisotropic
radiation field rapidly ensues. We now investigate the angular distribution of
cyclotron spectra emerging from an internally irradiated magnetized plasma with
a prescribed global geometry (either cylindrical or plane parallel) and the
effects of anisotropic photon injection on the line shapes. Varying the input
angular distribution permits a better understanding of the line formation
process in more realistic scenarios where the radiative mechanisms are
influenced by the intrinsic anisotropy of the field and by moderate
relativistic beaming. In general, the line features are most pronounced along
the directions of the anisotropic continuum injection and tend to be weakened
in other directions, relative to the line features resulting from an isotropic
continuum injection. We find that the enhancements at the line wings of the
fundamental, which appear prominantly in the case of isotropic continuum
injection, are strongly suppressed along the direction of anisotropy in the
case of beamed continuum injection, regardless of geometry or beaming pattern.

</DOC>
<DOC>
<DOCNO> 71349 </DOCNO>
Dispersion Laws for In-medium Fermions and Gluons in the CFL Phase of


  We evaluate several quantities appearing in the effective lagrangian for the
color-flavor locked phase of high density QCD using a formalism which exploits
the approximate decoupling of fermions with energy negative with respect to the
Fermi energy. The effective theory is essentially two-dimensional and exhibits
a Fermi velocity superselection rule, similar to the one found in the Heavy
Quark Effective Theory. Within the formalism we reproduce, using gradient
expansion, the results for the effective parameters of the Nambu-Goldstone
bosons. We also determine the dispersion laws for the gluons. By coupling the
theory to fermions and integrating over the two-dimensional degrees of freedom
we obtain the effective description of in-medium fermions.

</DOC>
<DOC>
<DOCNO> 152573 </DOCNO>
Derivative expansion for the effective action of chiral gauge fermions.


  Explicit exact formulas are presented, up to fourth order in a strict chiral
covariant derivative expansion, for the normal parity component of the
Euclidean effective action of even-dimensional Dirac fermions. The bosonic
background fields considered are scalar, pseudo-scalar, vector and axial
vector. No assumptions are made on the internal symmetry group and, in
particular, the scalar and pseudo-scalar fields need not be on the chiral
circle.

</DOC>
<DOC>
<DOCNO> 84707 </DOCNO>
Asymptotic freedom of general relativity and its possible consequences


  The formation of singularities in certain situations, such as the collapse of
massive stars, is one of the unresolved issues in classical general relativity.
Although no complete theory of quantum gravity exists it is often suggested
that quantum gravity effects may prevent the formation of these singularities.
In this article we will present arguments that a quantized theory of gravity
might exhibit asymptotic freedom. Considering the similarites between
non-Abelian gauge theories and general relativity it is conjectured that a
quantized theory of gravity may have a coupling strength which decreases with
increasing energy scale. Such a scale dependent coupling strength, could
provide a concrete mechanism for preventing the formation of singularities.

</DOC>
<DOC>
<DOCNO> 100898 </DOCNO>
On the Cauchy- and periodic boundary value problem for a certain class


  The Cauchy- and periodic boundary value problem for the nonlinear
Schroedinger equations in $n$ space dimensions [u_t - i\Delta u = (\nabla
\bar{u})^{\beta}, |\beta|=m \ge 2, u(0)=u_0 \in H^{s+1}_x] is shown to be
locally well posed for $s > s_c := \frac{n}{2} - \frac{1}{m-1}$, $s \ge 0$. In
the special case of space dimension $n=1$ a global $L^2$-result is obtained for
NLS with the nonlinearity $N(u)= \partial_x (\bar{u} ^2)$.
  The proof uses the Fourier restriction norm method.

</DOC>
<DOC>
<DOCNO> 122366 </DOCNO>
On the thermal conduction in tangled magnetic fields in clusters of


  Thermal conduction in tangled magnetic fields is reduced because heat
conducting electrons must travel along the field lines longer distances between
hot and cold regions of space than if there were no fields. We consider the
case when the tangled magnetic field has a weak homogeneous component. We
examine two simple models for temperature in clusters of galaxies: a
time-independent model and a time-dependent one. We find that the actual value
of the effective thermal conductivity in tangled magnetic fields depends on how
it is defined for a particular astrophysical problem. Our final conclusion is
that the heat conduction never totally suppressed but is usually important in
the central regions of galaxy clusters, and therefore, it should not be
neglected.

</DOC>
<DOC>
<DOCNO> 70688 </DOCNO>
Asymptotic Space-Time Behavior of HTL Gauge Propagator


  The asymptotic behavior as t\to\infty and r\to\infty of the hard-thermal-loop
propagator D^{\mu\nu}(t,r) is computed in the Coulomb gauge. The asymptotic
falloff is always a power law though generally different in the deep time-like
and space-like regions. The contributions of quasiparticle poles and Landau
branch cuts are computed. The most difficult calculation is the contribution of
the branch cut in the transverse propagator D^{ij}(t,r). For QED this produces
a leading behavior of order T/r in both the time-like and space-like regions.
The inclusion of a magnetic mass so as to describe QCD makes the leading
behavior 1/(Tr^{3}), thus improving the infrared convergence. The asymptotic
space-like behavior of all contributions (longitudinal and transverse, poles
and cuts) is confirmed by also computing in the Euclidean formalism and
analytically continuing. The results are compared will those for free gauge
bosons at finite temperature.

</DOC>
<DOC>
<DOCNO> 122733 </DOCNO>
Millimetric Ground Based Observation of CMBR Anisotropy at $\delta


  Results from the third campaign of a ground-based multi-band observation of
the millimeter emission of the sky from Tenerife (Canary Islands) are
presented. The instrument consists of a 0.45 meter diameter off-axis telescope
equipped with a 4-band multi-mode $^3He$ cooled photometer working at 1.1, 1.3,
2.1 and 3.1{\notetoeditor{These are effective wavelengths}} mm wavelengths. The
beam is well approximated by a Gaussian with 1$% ^{o}$.35 Full Width Half
Maximum (FWHM) at all wavelengths. The wide wavelength coverage of our
instrument allows us to characterize and reduce both the atmospheric and
galactic contamination in our data. The CMBR data is analyzed in 6 multipole
bands whose centers span the range $\ell=39$ to $\ell =134$ at the two longest
wavelengths (2.1 and 3.1 mm). A likelihood analysis indicates that we have
detected fluctuations in all bands at the two wavelengths. We have evidence of
a rise in the angular power spectrum from low $\ell $ to high $\ell $. Our
measured spectrum is consistent with current popular theories of large scale
structure formation, COBE, and other recent balloon-borne experiments with
similar wavelength coverage.

</DOC>
<DOC>
<DOCNO> 169620 </DOCNO>
Local symmetry properties of pure 3-qubit states


  Entanglement types of pure states of 3 qubits are classified by means of
their stabilisers in the group of local unitary operations. It is shown that
the stabiliser is generically discrete, and that a larger stabiliser indicates
a stationary value for some local invariant. We describe all the exceptional
states with enlarged stabilisers.

</DOC>
<DOC>
<DOCNO> 179043 </DOCNO>
Shell model study of the isobaric chains A=50, A=51 and A=52


  Shell model calculations in the full pf-shell are carried out for the A=50,
51 and 52 isobars. The most frequently used effective interactions for the
pf-shell, KB3 and FPD6 are revisited and their behaviour at the N=28 and Z=28
closures examined. Cures to their -relatively minor- defaults are proposed, and
a new mass dependent version called KB3G is released. Energy spectra,
electromagnetic transitions and moments as well as beta decay properties are
computed and compared with the experiment and with the results of the earlier
interactions. A high quality description is achieved. Other miscellaneous
topics are addressed; the Coulomb energy differences of the yrast states of the
mirror pair 51Mn-51Fe and the systematics of the magnetic moments of the N=28
isotones.

</DOC>
<DOC>
<DOCNO> 83079 </DOCNO>
Stochastic Model Checking for Multimedia


  Modern distributed systems include a class of applications in which
non-functional requirements are important. In particular, these applications
include multimedia facilities where real time constraints are crucial to their
correct functioning. In order to specify such systems it is necessary to
describe that events occur at times given by probability distributions and
stochastic automata have emerged as a useful technique by which such systems
can be specified and verified.
  However, stochastic descriptions are very general, in particular they allow
the use of general probability distribution functions, and therefore their
verification can be complex. In the last few years, model checking has emerged
as a useful verification tool for large systems.
  In this paper we describe two model checking algorithms for stochastic
automata. These algorithms consider how properties written in a simple
probabilistic real-time logic can be checked against a given stochastic
automaton.

</DOC>
<DOC>
<DOCNO> 69274 </DOCNO>
The effect of many sources on the genuine multiparticle correlations


  We report on a study aimed to explore the dependence of the genuine
multiparticle correlations on the number of sources when the influence of other
possible factors during multihadron production are avoided. The analysis
utilised the normalised cumulants calculated in three-dimensional phase space
of the reaction ee -> Z -> hadrons using a large Monte Carlo sample.
 The multi-sources events were simulated by overlaying a few independent single
ee annihilation events.
 It was found that as the number of sources increases, the cumulants do not
change significantly their structure, but those of an order higher than two
decrease fast in their magnitude.
 This reduction and its amount can be understood in terms of combinatorial
considerations of source mixing which dilutes the correlations.
 The diminishing of the genuine correlations is consistent with recent cumulant
measurements in hadron and nucleus induced reactions and should also be
relevant to other dynamical correlations like the Bose-Einstein one, in ee ->
WW -> hadrons and in nucleus-nucleus reactions.

</DOC>
<DOC>
<DOCNO> 117331 </DOCNO>
A measurement of Lorentz Angle of radiation-hard Pixel Sensors


  Silicon pixel detectors developed to meet LHC requirements were tested in a
beam at CERN in the framework of the ATLAS collaboration. The experimental
behaviour of irradiated and not-irradiated sensors in a magnetic field is
discussed. The measurement of the Lorentz angle for these sensors at different
operating conditions is presented. A simple model of the charge drift in
silicon before and after irradiation is presented. The good agreement between
the model predictions and the experimental results is shown.

</DOC>
<DOC>
<DOCNO> 170370 </DOCNO>
Self-Consistency of Thermal Jump Trajectories


  It is problematic to interpret the quantum jumps of an atom interacting with
thermal light in terms of counts at detectors monitoring the atom's inputs and
outputs. As an alternative, we develop an interpretation based on a
self-consistency argument. We include one mode of the thermal field in the
system Hamiltonian and describe its interaction with the atom by an entangled
quantum state while assuming that the other modes induce quantum jumps in the
usual fashion. In the weak-coupling limit, the photon number expectation of the
selected mode is also seen to execute quantum jumps, although more generally,
for stronger coupling, Rabi oscillations are observed; the equilibrium photon
number distribution is a Bose-Einstein distribution. Each mode may be viewed in
isolation in a similar fashion, and summing over their weak-coupling jump rates
returns the net jump rates for the atom assumed at the outset.

</DOC>
<DOC>
<DOCNO> 67854 </DOCNO>
Baryon magnetic moments in the QCD string approach


  Magnetic moments of baryons composed of light and strange quarks are computed
for the first time through the only parameter of the model -- string tension
$\sigma$. Resulting theoretical values differ from the experimental ones
typically by about
 10%.

</DOC>
<DOC>
<DOCNO> 13326 </DOCNO>
Magnetization Plateau of an S=1 Frustrated Spin Ladder


  We study the magnetization plateau at 1/4 of the saturation magnetization of
the S=1 antiferromagnetic spin ladder both analytically and numerically, with
the aim of explaining recent experimental results on BIP-TENO by Goto et al. We
propose two mechanisms for the plateau formation and clarify the plateau phase
diagram on the plane of the coupling constants between spins.

</DOC>
<DOC>
<DOCNO> 8617 </DOCNO>
Quantum Protectorates in the Cuprate Superconductors


  Following the identification of the pairing state, the major challenge in
understanding the cuprate superconductors has been determining the evolution
with doping and temperature of their anomalous normal state behavior. Key to
this understanding is the experimentally determined magnetic phase diagram for
the cuprates, which provides information on the protected magnetic properties
of the normal state, generic behavior that is reliably the same one system to
the next, regardless of details. I discuss the constraints this places on
candidate quantum protectorates, and the status of microscopic model
calculations for a protectorate consistent with these constraints, the nearly
antiferromagnetic Fermi liquid.

</DOC>
<DOC>
<DOCNO> 117137 </DOCNO>
Computer simulation approach to reliability and accuracy in EXAFS


  The frequency distribution of different parameters of an EXAFS spectrum can
be directly sampled by analysing a population of simulated spectra produced by
adding computer-generated noise to a reference pattern. The procedure gives
statistical estimators of the parameter obtained with different data processing
strategies to test the performance of a strategy, to evaluate the bias
introduced by random noise, and to clarify the amount of information actually
contained in an experimental spectrum. Examples are given for the two simple
local structures of an Ag atom sorrounded by two oxygens or by six iodines.

</DOC>
<DOC>
<DOCNO> 12388 </DOCNO>
The harmony, reflection and other principles of complex systems


  A set of general physical principles is proposed as the structural basis for
the theory of complex systems. First the concept of harmony is analyzed and its
different aspects are uncovered. Then the concept of reflection is defined and
illustrated by suggestive examples. Later we propose the principle of (random)
projection of symmetrically expanded prereality as the main description method
of complex systems.

</DOC>
<DOC>
<DOCNO> 10735 </DOCNO>
An Effective Field Model to High Temperature Superconductors: Fitting of


  We use an effective field model (transverse Ising model) to describe the
dependence on the temperature of the energy gap of some two-dimensional $(2-D)$
superconducting systems. The order parameter of this model is put in a direct
correspondence with that of the Ising model. Then, we use the exact relations
for the spontaneous magnetization of the Ising model in some $2-D$ lattices as
a means to fit the experimental results of $Bi_2Sr_2CaCu_2O_8 $ films obtained
through reflectivity measurements by Brunel et al [Phys. Rev. Lett. 66, 1346
(1991)] and the argon-annealed $Bi_2Sr_2CaCu_2O_8$ samples investigated by
Staufer et al [Phys. Rev. Lett. 68, 1069 (1992)] through Raman scattering. The
zero temperature energy gap $E_g(0)$ relations were evaluated in various $2-D$
lattices and also in the $(3-D)$ simple cubic lattice, for comparison. In the
square lattice case we obtained $E_g(0)=3.52kT_c$, coincidentally the same
number as the BCS result, and in the triangular lattice case we get
$E_g(0)=3.30kT_c$ in agreement with the experimental findings of Brunel et al.

</DOC>
<DOC>
<DOCNO> 121501 </DOCNO>
Photometric Properties of Low-Redshift Galaxy Clusters (LOCOS)


  A comprehensive multicolor survey was undertaken to investigate global
optical properties of Abell clusters of galaxies. This survey was christened
the "Low-Redshift Cluster Optical Survey" (LOCOS). LOCOS was devised to search
for patterns of galaxy evolution induced by the environment. The generated data
base contains accurate deep CCD photometric measurements (Kron-Cousins R,,B and
I) for a sample of 46 low-redshift (0.04 <= z <= 0.18) Abell clusters. This is
one of the few large surveys that included the contribution due to dwarf
galaxies (about 5.5 mag deeper than the R characteristic magnitude (M*); Ho=50
km/s/Mpc, qo=0). Due to space restrictions only the main results concerning the
variations at the bright-end of the luminosity function (LF) are presented
here. Other results are presented elsewhere (Lopez-Cruz & Yee 2000a,b). We have
detected clear variations at both the bright end and the faint end of the LF.
The nature of the variations at the bright end revealed that poor cD clusters
have dimmer M*. We can explain these variations as a result of dynamical
friction. On the other hand, non-cD clusters seem to have unaffected LFs. A
third class termed as binary clusters seems to be a transition class that might
have resulted from cluster-cluster mergers.

</DOC>
<DOC>
<DOCNO> 119071 </DOCNO>
Numerical Simulations of Convective Accretion Flows in Three Dimensions


  Advection-dominated accretion flows (ADAFs) are known to be convectively
unstable for low values of the viscosity parameter alpha. Two-dimensional
axisymmetric hydrodynamic simulations of such flows reveal a radial density
profile which is significantly flatter than the rho~r^{-3/2} expected for a
canonical ADAF. The modified density profile is the result of inward transport
of angular momentum by axisymmetric convective eddies. We present
three-dimensional hydrodynamic simulations of convective ADAFs which are free
of the assumption of axisymmetry. We find that the results are qualitatively
and quantitatively similar to those obtained with two-dimensional simulations.
In particular, the convective eddies are nearly axisymmetric and transport
angular momentum inward.

</DOC>
<DOC>
<DOCNO> 70647 </DOCNO>
Completing the Square to Find the Supersymmetric Matter Effective Action


  We consider generic N=1 supersymmetric matter coupled to linearized N=1
supergravity through the multiplet of currents. By completing the square, we
find the effective action giving the leading supergravity induced correction to
the matter dynamics, expressed explicitly as a quadratic form in the components
of the current multiplet. The effective action is supersymmetry invariant
through an interplay of the local terms arising from the auxiliary field
couplings, and the nonlocal terms arising from graviton and gravitino exchange,
neither of which is separately invariant. Having an explicit form for the
supergravity induced effective action is a first step in studying whether
supergravity corrections can lead to dynamical supersymmetry breaking in
supersymmetric matter dynamics. In Appendices we give explicit expressions for
the currents, in our notational conventions, in the Wess-Zumino and
supersymmetric Yang Mills models.

</DOC>
<DOC>
<DOCNO> 101707 </DOCNO>
Multipliers of the Hardy space H^1 and power bounded operators


  We study the space of functions $\phi\colon \NN\to \CC$ such that there is a
Hilbert space $H$, a power bounded operator $T$ in $B(H)$ and vectors
$\xi,\eta$ in $H$ such that $$\phi(n) = < T^n\xi,\eta>.$$ This implies that the
matrix $(\phi(i+j))_{i,j\ge 0}$ is a Schur multiplier of $B(\ell_2)$ or
equivalently is in the space $(\ell_1 \buildrel {\vee}\over {\otimes}
\ell_1)^*$. We show that the converse does not hold, which answers a question
raised by Peller [Pe]. Our approach makes use of a new class of Fourier
multipliers of $H^1$ which we call ``shift-bounded''. We show that there is a
$\phi$ which is a ``completely bounded'' multiplier of $H^1$, or equivalently
for which $(\phi(i+j))_{i,j\ge 0}$ is a bounded Schur multiplier of
$B(\ell_2)$, but which is not ``shift-bounded'' on $H^1$. We also give a
characterization of ``completely shift-bounded'' multipliers on $H^1$.

</DOC>
<DOC>
<DOCNO> 12011 </DOCNO>
Long Range Order at Low Temperature in Dipolar Spin Ice


  Recently it has been suggested that long range magnetic dipolar interactions
are responsible for spin ice behavior in the Ising pyrochlore magnets ${\rm
Dy_{2}Ti_{2}O_{7}}$ and ${\rm Ho_{2}Ti_{2}O_{7}}$. We report here numerical
results on the low temperature properties of the dipolar spin ice model,
obtained via a new loop algorithm which greatly improves the dynamics at low
temperature. We recover the previously reported missing entropy in this model,
and find a first order transition to a long range ordered phase with zero total
magnetization at very low temperature. We discuss the relevance of these
results to ${\rm Dy_{2}Ti_{2}O_{7}}$ and ${\rm Ho_{2}Ti_{2}O_{7}}$.

</DOC>
<DOC>
<DOCNO> 121239 </DOCNO>
Rotation and H-alpha Emission Above and Below the Substellar Boundary


  I present the results of a multiyear survey of very low mass stars and brown
dwarfs, at high spectral resolution. The spectra were gathered with the HIRES
echelle at the Keck Observatory. Some of these objects are stellar and others
are substellar (or ambiguous). Early indications that such objects can be
rapidly rotating but display little H-alpha emission turn out to be commonly
true. This is the opposite of the relation between rotation and activity in
solar-type stars. The H-alpha surface flux drops precipitously at the bottom of
the main sequence, and seems to be related to the luminosity or temperature of
the objects. There is a general trend to higher rotation velocities as one
looks at objects of lower luminosity. I discuss several possible explanations
for these results. The dynamos for these objects are probably fully turbulent,
driven by convection, and thus more directly related to the object's
luminosity. They may be quenched when the rotational velocities become too fast
in comparison to the convective velocities
 (supersaturation). Another possibility is that the atmospheres of the cooler
objects are becoming sufficiently neutral to decouple atmospheric motions from
the field. Either of these could explain why young brown dwarfs can be
magnetically active while older brown dwarfs are not. A final possibility is
that instead of being quenched, the field configuration in rapid rotators
changes to a less conducive form for dissipative heating. This could explain
why flares are occasionally seen on generally inactive objects.

</DOC>
<DOC>
<DOCNO> 11278 </DOCNO>
Nonlinear lattice model of viscoelastic Mode III fracture


  We study the effect of general nonlinear force laws in viscoelastic lattice
models of fracture, focusing on the existence and stability of steady-state
Mode III cracks. We show that the hysteretic behavior at small driving is very
sensitive to the smoothness of the force law. At large driving, we find a Hopf
bifurcation to a straight crack whose velocity is periodic in time. The
frequency of the unstable bifurcating mode depends on the smoothness of the
potential, but is very close to an exact period-doubling instability. Slightly
above the onset of the instability, the system settles into a exactly
period-doubled state, presumably connected to the aforementioned bifurcation
structure. We explicitly solve for this new state and map out its
velocity-driving relation.

</DOC>
<DOC>
<DOCNO> 99721 </DOCNO>
Segre varieties, CR geometry and Lie symmetries of second order PDE


  We show that biholomorphic automorphisms of a real analytic CR manifold can
be considered as (pointwise) Lie symmetries of a holomorphic second order PDE
system defining its Segre family. This allows to use general methods of the
geometric PDE theory in order to study the CR geometry of real analytic
manifolds.

</DOC>
<DOC>
<DOCNO> 70102 </DOCNO>
Brane Networks in AdS Space


  We present static solutions to Einstein's equations corresponding to the most
general network of $N$ orthogonal families of $(2+N)$-branes in
$(4+N)$-dimensional $AdS$ spacetimes. The bulk cosmological constant can take a
different value in each cell enclosed by intersecting branes and the extra
dimensions can be compact or noncompact. In each family of branes the
inter-brane spacing is arbitrary. The extra dimensions may be any or all of the
manifolds, $R^1$, $R^1/Z_2$, $S^1$ and $S^1/Z_2$. Only when the extra
dimensions are $R^1$ or/and $R^1/Z_2$, can networks consisting solely of
positive tension branes be constructed. Such configurations may find
application in models with localized gravity and symmetry breaking by shining.

</DOC>
<DOC>
<DOCNO> 151662 </DOCNO>
Chiral Symmetry {\it Breaking} in the Light-Cone Representation


  In this paper I shall discuss the way in which vacuum structure and
condensates occur in the light-cone representation. I shall particularly
emphasize the mechanism by which the mass squared of a composite such as the
pion comes to depend linearly on the bare mass of its Fermion constituents. I
shall give details in two dimensions then discuss the case of four dimensions
more speculatively.

</DOC>
<DOC>
<DOCNO> 12236 </DOCNO>
A Numerical Study on the Evolution of Portfolio Rules: Is CAPM Fit for


  In this paper we test computationally the performance of CAPM in an
evolutionary setting. In particular we study the stability of wealth
distribution in a financial market where some traders invest as prescribed by
CAPM and others behave according to different portfolio rules. Our study is
motivated by recent analytical results that show that, whenever a logarithmic
utility maximiser enters the market, traders who either ``believe'' in CAPM and
use it as a rule of thumb for their portfolio decisions, or are endowed with
genuine mean-variance preferences, vanish in the long run. Our analysis
provides further insights and extends these results. We simulate a sequence of
trades in a financial market and: first, we address the issue of how long is
the long run in different parametric settings; second, we study the effect of
heterogeneous savings behaviour on asymptotic wealth shares. We find that CAPM
is particularly ``unfit'' for highly risky environments.

</DOC>
<DOC>
<DOCNO> 39806 </DOCNO>
New experimental test of Bell inequalities by the use of a non-maximally


  We report on the first realisation of a test of Bell inequalities using
non-maximally entangled states. It is based on the superposition of type I
parametric down conversion produced in two different non-linear crystals pumped
by the same laser, but with different polarisations. We discuss the advantages
and the possible developments of this configuration.

</DOC>
<DOC>
<DOCNO> 68823 </DOCNO>
Observational constraints upon quintessence models arising from moduli


  We study observational constraints on cosmological models with a quintessence
arising from moduli fields. The scalar field potential is given by a double
exponential potential V=V_0 exp(-A e^{sqrt{2} kappa phi}). After reviewing the
properties of the solutions, from a dynamical systems phase space analysis, we
consider the constraints on parameter values imposed by luminosity distances
from the 60 Type IA supernovae published by Perlmutter et al., and also from
gravitational lensing statistics of distant quasars. We also update the
constraints on models with a single exponential potential V=V_0 e^{-lambda
kappa phi}.

</DOC>
<DOC>
<DOCNO> 13235 </DOCNO>
Dynamical Susceptibility in KH2PO4-type Crystals above and below Tc


  The time dependent cluster approximation called the path probability method
(PPM) is applied to a pseudo-spin Ising Hamiltonian of the Slater-Takagi model
for KH2PO4-type hydrogen-bonded ferroelectrics in order to calculate the
homogeneous dynamical susceptibility above and below the ferroelectric
transition temperature. Above the transition temperature all the calculations
are carried out analytically in the cactus approximation of the PPM. Below the
transition temperature the dynamical susceptibility is also calculated
accurately since the analytical solution of spontaneous polarization in the
ferroelectric phase can be utilized. When the temperature is approached from
both sides of the transition temperature, only one of relaxation times shows a
critical slowing down and makes a main contribution to the dynamical
susceptibility. The discrepancy from Slater model (ice-rule limit) is discussed
in comparison with some experimental data.

</DOC>
<DOC>
<DOCNO> 84476 </DOCNO>
Pulsed pump in optical displacement transducer for experiments with


  The sensitivity of the displacement transducer pumped with a train of
high-intensity laser pulses is estimated. Due to the multicomponent character
of the pump a consideration of transformations of the signal and the noises
between optical modes plays an important role in estimation of the potential
sensitivity. An expression for the minimal detectable external classical force
resembles those for the continuous wave pumping with substitution of the laser
power by a time averaged power of pulsed laser. Possible scheme for back action
noise compensation for such transducers is considered. For full suppression of
back action noise the field of local oscillator has to be pulsed with the same
time dependence as the pump field.

</DOC>
<DOC>
<DOCNO> 116906 </DOCNO>
Design of the SNS Normal Conducting Linac RF Control System


  The Spallation Neutron Source (SNS) is being designed for operation in 2004.
The SNS is a 1 GeV machine consisting of a combination normal-conducting and
super-conducting linac as well as a ring and target area. The linac front end
is a 402.5 MHz RFQ being developed by Lawrence Berkeley Lab. The DTL (at 402.5
MHz) and the CCL (at 805 MHz) stages are being developed by Los Alamos National
Laboratory. The expected output energy of the DTL is 87 MeV and that of the CCL
is 185 MeV. The RF control system under development for the linac is based on
the Low Energy Demonstration Accelerator (LEDA) control system with some new
features. This paper will discuss the new design approach and its benefits.
Block diagrams and circuit specifics will be addressed. The normal conducting
RF control system will be described in detail with references to the
super-conducting control system where appropriate.

</DOC>
<DOC>
<DOCNO> 170216 </DOCNO>
Conditional quantum state engineering in repeated 2-photon down


  The U(1,1) and U(2) transformations realized by three-mode interaction in the
respective parametric approximations are studied in conditional measurement,
and the corresponding non-unitary transformation operators are derived. As an
application, the preparation of single-mode quantum states using an optical
feedback loop is discussed, with special emphasis of Fock state preparation.
For that example, the influence of non-perfect detection and feedback is also
considered.

</DOC>
<DOC>
<DOCNO> 11086 </DOCNO>
Supersymmetric Hubbard Operators


  We develop a supersymmetric representation of the Hubbard operator which
unifies the slave boson and slave fermion representations into a single $U
(1)\times SU (1| 1)$ gauge theory, a group with larger symmetry than the
product of two $U (1)$ gauge groups. These representations of the Hubbard
operator can be used to incorporate strong Hund's interactions in
multi-electron atoms as a constraint. We show how this method can be combined
with the $SP (N)$ group to yield a locally supersymmetric large-N formulation
of the $t-J$ model.

</DOC>
<DOC>
<DOCNO> 101581 </DOCNO>
Homotopy type of Symplectomorphism Groups of S^2\times S^2


  Let $M$ be $S^2 \times S^2$. $M$ carries a family of symplectic forms
$\omega_{\lambda}$, where $\lambda \geq 0$ determines the cohomology class
$[\omega_{\lambda}]$. This paper calculates the homotopy type of the group
$G_{\lambda}$ of symplectomorphisms of $(M,\omega_{\lambda})$ when $0 < \lambda
\leq 1$. We show that if $\lambda$ is in this range $G_{\lambda}$ contains two
finite dimensional Lie groups that generate its homotopy. A key step in this
work is to calculate the mod 2 homology of $G_{\lambda}$. Although this
homotopy has a finite number of generators with respect to the Pontryagin
product, it is unexpected large because it contains a free noncommutative ring
with 3 generators. Our arguments involve a study of the space of
$\omega_{\lambda}$-compatible almost complex structures on $M$.

</DOC>
<DOC>
<DOCNO> 9509 </DOCNO>
Magnetic relaxation and magnetization field dependence measurements in


  We reported a systematic change in the average magnetic relaxation rate,
after the application and removal of a 5 T magnetic field, in a polycrystalline
sample of La0.5Ca0.5MnO3. Magnetic relaxation measurements and magnetization
versus field curves were taken from 10 K to 160 K. The long time behavior of
the relaxation curves was approximately logarithmic in all cases. Keywords:
Charge Ordering, Relaxation, Magnetic measurements

</DOC>
<DOC>
<DOCNO> 80828 </DOCNO>
On the Triviality of Textbook Quantum Electrodynamics


  By adding a small, irrelevant four fermi interaction to the action of lattice
Quantum Electrodynamics (QED), the theory can be simulated with massless quarks
in a vacuum free of lattice monopoles. This allows an ab initio high precision,
controlled study of the existence of "textbook" Quantum Electrodynamics with
several species of fermions. The lattice theory possesses a second order chiral
phase transition which we show is logarithmically trivial. The logarithms of
triviality, which modify mean field scaling laws, are pinpointed in several
observables. The result supports Landau's contention that perturbative QED
suffers from complete screening and would have a vanishing fine structure
constant in the absence of a cutoff.

</DOC>
<DOC>
<DOCNO> 119042 </DOCNO>
Boomerang returns unexpectedly


  Experimental study of the anisotropy in the cosmic microwave background (CMB)
is gathering momentum. The eagerly awaited Boomerang results have lived up to
expectations. They provide convincing evidence in favor of the standard
paradigm: the Universe is close to flat and with primordial fluctuations which
are redolent of inflation. Further scrutiny reveals something even more
exciting however -- two hints that there may be some unforeseen physical
effects. Firstly the primary acoustic peak appears at slightly larger scales
than expected. Although this may be explicable through a combination of mundane
effects, we suggest it is also prudent to consider the possibility that the
Universe might be marginally closed. The other hint is provided by a second
peak which appears less prominent than expected. This may indicate one of a
number of possibilities, including increased damping length or tilted initial
conditions, but also breaking of coherence or features in the initial power
spectrum. Further data should test whether the current concordance model needs
only to be tweaked, or to be enhanced in some fundamental way.

</DOC>
<DOC>
<DOCNO> 70383 </DOCNO>
Bremsstrahlung from a Microscopic Model of Relativistic Heavy Ion


  We compute bremsstrahlung arising from the acceleration of individual charged
baryons and mesons during the time evolution of high-energy Au+Au collisions at
the Relativistic Heavy Ion Collider using a microscopic transport model. We
elucidate the connection between bremsstrahlung and charge stopping by
colliding artificial pure proton on pure neutron nuclei. From the intensity of
low energy bremsstrahlung, the time scale and the degree of stopping could be
accurately extracted without measuring any hadronic observables.

</DOC>
<DOC>
<DOCNO> 70541 </DOCNO>
Beta-functions in Yang-Mills Theory from Non-critical String


  The renormalization group equations of the Yang-Mills theory are examined in
the non-critical string theory according to the framework of the holography.
Under a simple ansatz for the tachyon, we could find several interesting
solutions which are classified by the value of the tachyon potential at the
vacuum. We show two typical, asymptotic-free solutions which are different in
their infrared behaviors. For both types of solutions, we could obtain
quark-confinement potential from the Wilson-loop. The stability of the tachyon
and the ZigZag symmetry are also discussed for these solutions.

</DOC>
<DOC>
<DOCNO> 39736 </DOCNO>
Solar Neutrinos: What Next?


  I summarize the current state of solar neutrino research and then give my
answer to the question: What should we do next?

</DOC>
<DOC>
<DOCNO> 84774 </DOCNO>
Static Cosmological Solutions of the Einstein-Yang-Mills-Higgs Equations


  Numerical evidence is presented for the existence of a new family of static,
globally regular `cosmological' solutions of the spherically symmetric
Einstein-Yang-Mills-Higgs equations. These solutions are characterized by two
natural numbers ($m\geq 1$, $n\geq 0$), the number of nodes of the Yang-Mills
and Higgs field respectively. The corresponding spacetimes are static with
spatially compact sections with 3-sphere topology.

</DOC>
<DOC>
<DOCNO> 150405 </DOCNO>
Closed constraint algebras and path integrals for loop group actions


  In this note we study systems with a closed algebra of second class
constraints. We describe a construction of the reduced theory that resembles
the conventional treatment of first class constraints. It suggests, in
particular, to compute the symplectic form on the reduced space by a fiber
integral of the symplectic form on the original space. This approach is then
applied to a class of systems with loop group symmetry. The chiral anomaly of
the loop group action spoils the first class character of the constraints but
not their closure. Proceeding along the general lines described above, we
obtain a 2-form from a fiber (path)integral. This form is not closed as a
relict of the anomaly. Examples of such reduced spaces are provided by D-branes
on group manifolds with WZW action.

</DOC>
<DOC>
<DOCNO> 120439 </DOCNO>
Self-Similar Hot Accretion Flow onto a Neutron Star


  We consider hot, two-temperature, viscous accretion onto a rotating,
unmagnetized neutron star. We assume Coulomb coupling betweenthe protons and
electrons, and free-free cooling from the electrons. We show that the accretion
flow has an extended settling region which can be described by means of two
analytical self-similar solutions: a two-temperature solution which is valid in
an inner zone, r<10^{2.5}, where r is the radius in Schwarzchild units; and a
one-temperature solution which is valid in an outer zone, r>10^{2.5}. In both
zones the density varies as \rho ~ r^{-2} and the angular velocity as \Omega ~
r^{-3/2}. We solve the flow equations numerically and confirm that the
analytical solutions are accurate. The settling flow radiates the energy
dissipated by viscosity; so it is not advection-dominated. Except for the
radial velocity, all other gas properties - density, angular velocity,
temperature, luminosity, angular momentum flux - are independent of the mass
accretion rate; these quantities do depend sensitively on the spin of the
neutron star. The angular momentum flux is outward under most conditions;
therefore, the central star is nearly always spun-down. The luminosity of the
settling zone arises from the rotational energy that is released as the star is
braked by viscosity, and the contribution from gravity is small; hence the
radiative efficiency can be arbitrarily large at low $\mdot$. For reasonable
values of the gas adiabatic index, the Bernoulli parameter is negative;
therefore, a strong outflow or wind is not expected. The flow is convectively
stable, but may be thermally unstable. The described solution is not
advection-dominated; however, when the spin of the star is small enough, it
transforms smoothly to an advection-dominated branch of solution.

</DOC>
<DOC>
<DOCNO> 13004 </DOCNO>
Time evolution of Grover's algorithm with imperfections


  We study imperfection effects on time evolution of Grover's algorithm on
quantum computer. We introduce an effective two-level model with dissipation
and stochasty, which is based upon the idea that ideal Grover's algorithm
operates in 2 dimensional Hilbert space. The simulation results of both are
compared and it is found that they are in good agreement for appropriately
tuned parameters. It turns out that the main features of Grover's algorithm
with imperfections can be understood in terms of two basic mechanisms, i.e., a
diffusion of probability density into full Hilbert space and a stochastic
rotation within the original 2 dimensional Hilbert space.

</DOC>
<DOC>
<DOCNO> 70143 </DOCNO>
Disentangling the Imaginary-Time Formalism at Finite Temperature


  We rewrite the imaginary-time formalism of finite temperature field theory in
a form that all graphs used in calculating physical processes do not have any
loops. Any production of a particle from a heat bath which is itself not
thermalized or the decay and absorption of a similar particle in the bath is
expressed entirely in terms of the sum of particle interaction processes. These
are themselves very general in meaning. They can be straight forward
interactions or the more subtle and less well-known purely interference
processes that do not have a counter part in the vacuum.

</DOC>
<DOC>
<DOCNO> 152320 </DOCNO>
D-branes on a Noncompact Singular Calabi-Yau Manifold


  We investigate D-branes on a noncompact singular Calabi-Yau manifold by using
the boundary CFT description, and calculate the open string Witten indices
between the boundary states. The B-type D-branes turn out to be characterized
by the properties of a compact positively curved manifold. We give geometric
interpretations to these boundary states in terms of coherent sheaves of the
manifold.

</DOC>
<DOC>
<DOCNO> 12734 </DOCNO>
Phase behavior of rod-like virus and polymer mixture


  We have prepared a homologous series of filamentous viruses with varying
contour length using molecular cloning techniques. These viruses are
monodisperse enough to form a stable smectic phase. Two systems are studied.
The first system consists of viruses to which polymers are covalently attached
to the virus surface. Through studies of the isotropic - cholesteric phase
transition we demonstrate that covalently attached polymers alter the effective
diameter of the virus. Additionally, we have produced mixtures of viruses whose
ratio of effective diameters varies by a factor of five. The second system is
composed of mixtures of rod-like viruses and non-absorbing polymers. With this
system we study the kinetics of the isotropic - smectic phase transition and
describe observations of a number of novel metastable structures of unexpected
complexity.

</DOC>
<DOC>
<DOCNO> 72260 </DOCNO>
Covariant Level-Classification Scheme and Chiral Symmetry


  Starting from the bi-local Klein-Gordon Equation with spin-independent
squared-mass operator, we give a covariant quark representation of general
composite meson systems with definite Lorentz transformation properties. For
benefit of this representation we are able to deduce automatically the
transformation rules of composite mesons for general symmetry operations from
those of constituent (exciton) quarks. Applying this we investigate especially
physical implication of chiral symmetry for the meson systems, and present a
covariant level-classification scheme, leading to a possible existence of new
meson multiplets of "chiralons."

</DOC>
<DOC>
<DOCNO> 12847 </DOCNO>
Electron energy relaxation in the presence of magnetic impurities


  We study inelastic electron-electron scattering mediated by the exchange
interaction of electrons with magnetic impurities, and find the kernel of the
corresponding two-particle collision integral. In a wide region of parameters,
the kernel K is proportional to the inverse square of the transferred energy,
$K\propto J^4/E^2$. The exchange constant J is renormalized due to the Kondo
effect, yielding an additional weak dependence of K on the energies of the
colliding electrons. At small energy transfers, the $1/E^2$ divergence is cut
off; the cut-off energy is determined by the dynamics of the impurity spins.
The obtained results may provide a quantitative explanation of the experiments
of Pothier et al. [Phys. Rev. Lett. 79, 3490 (1997)] on anomalously strong
energy relaxation in short metallic wires.

</DOC>
<DOC>
<DOCNO> 152057 </DOCNO>
3-branes on resolved conifold


  The type IIB supergravity solution describing a collection of regular and
fractional D3 branes on the conifold (hep-th/0002159) was recently generalized
to the case of the deformed conifold (hep-th/0007191). Here we present another
generalization -- when the conifold is replaced by the resolved conifold. This
solution can be found in two different ways: (i) by first explicitly
constructing the Ricci-flat Kahler metric on resolved conifold and then solving
the supergravity equations for the D3-brane ansatz with constant dilaton and
(self-dual) 3-form fluxes; (ii) by generalizing the ``conifold'' ansatz of
hep-th/0002159 in a natural ``asymmetric'' way so that the 1-d action
describing radial evolution still admits a superpotential and then solving the
resulting 1-st order system. The superpotentials for the ``resolved'' and
``deformed'' conifold cases turn out to have essentially the same simple
structure. The solution in the resolved conifold case has the same asymptotic
UV behaviour as in the conifold case, but unlike the deformed conifold case is
still singular in the IR. The naked singularity is of repulson type and may
have a brane resolution.

</DOC>
<DOC>
<DOCNO> 152369 </DOCNO>
A power law for the lowest eigenvalue in localized massive gravity


  This short note contains a detailed analysis to find the right power law the
lowest eigenvalue of a localized massive graviton bound state in a four
dimensional AdS background has to satisfy. In contrast to a linear dependence
of the cosmological constant we find a quadratic one [hep-th/0011156].

</DOC>
<DOC>
<DOCNO> 151110 </DOCNO>
Stringy Fuzziness as the Custodian of Time-Space Noncommutativity


  We study aspects of obtaining field theories with noncommuting time-space
coordinates as limits of open-string theories in constant electric-field
backgrounds. We find that, within the standard closed-string backgrounds, there
is an obstruction to decoupling the time-space noncommutativity scale from that
of the string fuzziness scale. We speculate that this censorship may be
string-theory's way of protecting the causality and unitarity structure. We
study the moduli space of the obstruction in terms of the open- and
closed-string backgrounds. Cases of both zero and infinite brane tensions as
well as zero string couplings are obtained. A decoupling can be achieved
formally by considering complex values of the dilaton and inverting the role of
space and time in the light cone. This is reminiscent of a black-hole horizon.
We study the corresponding supergravity solution in the large-N limit and find
that the geometry has a naked singularity at the physical scale of
noncommutativity.

</DOC>
<DOC>
<DOCNO> 10952 </DOCNO>
Energetics and geometry of excitations in random systems


  Methods for studying droplets in models with quenched disorder are critically
examined. Low energy excitations in two dimensional models are investigated by
finding minimal energy interior excitations and by computing the effect of bulk
perturbations. The numerical data support the assumptions of compact droplets
and a single exponent for droplet energy scaling. Analytic calculations show
how strong corrections to power laws can result when samples and droplets are
averaged over. Such corrections can explain apparent discrepancies in several
previous numerical results for spin glasses.

</DOC>
<DOC>
<DOCNO> 71438 </DOCNO>
Techniques for the Top Squark Search at the Fermilab Tevatron


  This dissertation addresses the question of how to detect light top squarks
at the upgraded Fermilab Tevatron collider. After a brief introduction to
supersymmetry, the basic phenomenology of the light stop is reviewed and the
current experimental situation is surveyed. The analysis presented here is
based on collider event simulations. The main decay modes accessible to the
Tevatron are studied, feasible discovery channels are identified, and recipes
for experimental analysis are proposed. It is found that stops with masses up
to the top quark mass are liable to detection under these schemes with the data
from a few years' running at the upgraded Tevatron. With such an extended run,
significant portions of parameter space may be probed.

</DOC>
<DOC>
<DOCNO> 39613 </DOCNO>
Recent Low x and Diffractive Collider Data


  Selected recent data from collider experiments pertaining to the
understanding of QCD at low Bjorken-x are reviewed. The status of QCD and Regge
factorisation in hard diffractive interactions is discussed in terms of data
from HERA and the Tevatron. The possibility of anomalous behaviour in the
$\gamma \gamma$ total cross section is confronted with the most recent
measurements from LEP. Data from all three colliders that are sensitive to
possible BFKL effects are presented and different interpretations are
discussed.

</DOC>
<DOC>
<DOCNO> 71579 </DOCNO>
The Cleo III Rich Detector


  CLEO III upgrade was completed with the integration of Ring Imaging
CHerenkov(RICH) detector for charged particle identification. The design of
this cylindrical detector consists of LiF crystal radiators and multi-wire
proportional chamber photon detectors coupled through a N2 filled expansion
gap. Early performance on K/pion separation is presented.

</DOC>
<DOC>
<DOCNO> 68829 </DOCNO>
Black hole constraints on the running-mass inflation model


  The running-mass inflation model, which has strong motivation from particle
physics, predicts density perturbations whose spectral index is strongly
scale-dependent. For a large part of parameter space the spectrum rises sharply
to short scales. In this paper we compute the production of primordial black
holes, using both analytic and numerical calculation of the density
perturbation spectra. Observational constraints from black hole production are
shown to exclude a large region of otherwise permissible parameter space.

</DOC>
<DOC>
<DOCNO> 152111 </DOCNO>
Light-like (2,0) Noncommutativity and Light-Cone Rigid Open Membrane


  The six-dimensional (2,0) field theory admits a generalized
``noncommutative'' deformation associated with turning on a large null 3-form
field strength. This theory is studied using its discrete light-cone
formulation as quantum mechanics on a blow-up of the ADHM moduli space. We show
how to interpret the ADHM manifold as configurations of open membranes, and
check our results against basic space-time considerations.

</DOC>
<DOC>
<DOCNO> 100969 </DOCNO>
Some examples of rigid representations


  Consider the Deligne-Simpson problem: {\em give necessary and sufficient
conditions for the choice of the conjugacy classes $C_j\subset GL(n,{\bf C})$
(resp. $c_j\subset gl(n,{\bf C})$) so that there exist irreducible
$(p+1)$-tuples of matrices $M_j\in C_j$ (resp. $A_j\in c_j$) satisfying the
equality $M_1... M_{p+1}=I$ (resp. $A_1+... +A_{p+1}=0$)}. The matrices $M_j$
and $A_j$ are interpreted as monodromy operators and as matrices-residua of
fuchsian systems on Riemann's sphere.
  We give new examples of existence of such $(p+1)$-tuples of matrices $M_j$
(resp. $A_j$) which are {\em rigid}, i.e. unique up to conjugacy once the
classes $C_j$ (resp. $c_j$) are fixed. For rigid representations the sum of the
dimensions of the classes $C_j$ (resp. $c_j$) equals $2n^2-2$.

</DOC>
<DOC>
<DOCNO> 72184 </DOCNO>
Collider Implications of Kaluza-Klein Excitations of the Gluons


  We consider an asymmetric string compactification scenario in which the SM
gauge bosons can propagate into one TeV$^{-1}$-size extra compact dimension.
These gauge bosons have associated KK excitations that present additional
contributions to the SM processes. We calculate the effects that the KK
excitations of the gluons, $g^{\star}$'s, have on multijet final state
production in proton-proton collisions at the Large Hadron Collider energy. In
the case of dijet final states with very high $p_{{}_T}$, the KK signal due to
the exchanges of the $g^{\star}$'s is several factors greater than the SM
background for compactification scales as high as about 7 TeV. The
high-$p_{{}_T}$ effect is not as dramatic for the direct production of a single
on-shell $g^{\star}$, which subsequently decays into $q$-$\bar{q}$ pairs, where
the KK signal significantly exceeds the SM three-jet background for
compactification scales up to about 3 TeV. We also present our results for the
four-jet final state signal from the direct production of two on-shell
$g^{\star}$'s.

</DOC>
<DOC>
<DOCNO> 68972 </DOCNO>
A mass relation for neutrinos


  A generalization of the well-known Georgi-Jarlskog relation m_{\mu}/m_{\tau}
= 3 (m_s/m_b) to neutrinos is found in the context of SO(10). This new relation
is m_{\nu_\mu}/m_{\nu_\tau} = 16 (m_c/m_t), which is consistent with present
data, assuming the small-angle MSW solution to the solar neutrino problem.

</DOC>
<DOC>
<DOCNO> 12673 </DOCNO>
Optimal shapes of compact strings


  Optimal geometrical arrangements, such as the stacking of atoms, are of
relevance in diverse disciplines. A classic problem is the determination of the
optimal arrangement of spheres in three dimensions in order to achieve the
highest packing fraction; only recently has it been proved that the answer for
infinite systems is a face-centred-cubic lattice. This simply stated problem
has had a profound impact in many areas, ranging from the crystallization and
melting of atomic systems, to optimal packing of objects and subdivision of
space. Here we study an analogous problem--that of determining the optimal
shapes of closely packed compact strings. This problem is a mathematical
idealization of situations commonly encountered in biology, chemistry and
physics, involving the optimal structure of folded polymeric chains. We find
that, in cases where boundary effects are not dominant, helices with a
particular pitch-radius ratio are selected. Interestingly, the same geometry is
observed in helices in naturally-occurring proteins.

</DOC>
<DOC>
<DOCNO> 122805 </DOCNO>
Probing the First Stars with Hydrogen and Helium Recombination Emission


  Unusual patterns of recombination emission from gas ionized by metal-free
stars may distinguish early star-forming galaxies from their present-day
counterparts. This pattern arises from the harder ionizing spectrum expected
from metal-free stars, which strongly enhances the strength of He II
recombination lines. Our calculations indicate that line fluxes of He II 1640
and 4686 are sufficiently large to be detected by narrowband and spectroscopic
searches for high-redshift emission-line sources at redshift z ~ 5 using
current instruments. An unknown fraction of Lya emitters may harbor
low-metallicity or metal-free stars. As the predicted He II 1640 flux is
comparable to and may exceed hydrogen Lya, searches for high-redshift galaxies
should consider He II recombination lines as possible identifications for
single emission lines in observed spectra. Spectra of metal-free stars may show
both H I and He II emission lines, improving the constraints on their redshift
and identification. We assess the considerable uncertainties that affect our
expectations for the detection and identification of true first-generation
stars with present search techniques, including the role of stellar mass loss
in spectral evolution and the confusion of ionization by primordial stellar
sources and AGN in the early universe.

</DOC>
<DOC>
<DOCNO> 102175 </DOCNO>
A proof of the Tsygan formality conjecture for chains


  We extend the Kontsevich formality $L_\infty$-morphism $\U\colon
T^\ndot_\poly(\R^d)\to\D^\ndot_\poly(\R^d)$ to an $L_\infty$-morphism of an
$L_\infty$-modules over $T^\ndot_\poly(\R^d)$, $\hat \U\colon
C_\ndot(A,A)\to\Omega^\ndot(\R^d)$, $A=C^\infty(\R^d)$. The construction of the
map $\hat \U$ is given in Kontsevich-type integrals. The conjecture that such
an $L_\infty$-morphism exists is due to Boris Tsygan \cite{Ts}. As an
application, we obtain an explicit formula for isomorphism $A_*/[A_*,A_*]\simto
A/\{A,A\}$ ($A_*$ is the Kontsevich deformation quantization of the algebra $A$
by a Poisson bivector field, and $\{{,}\}$ is the Poisson bracket). We also
formulate a conjecture extending the Kontsevich theorem on the cup-products to
this context. The conjecture implies a generalization of the Duflo formula, and
many other things.

</DOC>
<DOC>
<DOCNO> 9279 </DOCNO>
Scaling near Quantum Chaos Border in Interacting Fermi Systems


  The emergence of quantum chaos for interacting Fermi systems is investigated
by numerical calculation of the level spacing distribution $P(s)$ as function
of interaction strength $U$ and the excitation energy $\epsilon$ above the
Fermi level. As $U$ increases, $P(s)$ undergoes a transition from Poissonian
(nonchaotic) to Wigner-Dyson (chaotic) statistics and the transition is
described by a single scaling parameter given by $Z = (U \epsilon^{\alpha}-u_0)
\epsilon^{1/2\nu}$, where $u_0$ is a constant. While the exponent $\alpha$,
which determines the global change of the chaos border, is indecisive within a
broad range of $0.9 \sim 2.0$, finite value of $\nu$, which comes from the
increase of the Fock space size with $\epsilon$, suggests that the transition
becomes sharp as $\epsilon$ increases.

</DOC>
<DOC>
<DOCNO> 68449 </DOCNO>
How Valuable is Polarization at a Muon Collider? A Test Case:


  We study the use of polarization asymmetries at a muon collider to determine
the CP-even and CP-odd couplings of a Higgs boson to $\mu^+mu^-$. We determine
achievable accuracy as a function of beam polarization and luminosity. The
appropriate techniques for dealing with the polarization precession are
outlined. Strategies especially appropriate for a two-Higgs-doublet model
(including the MSSM) are given. Our general conclusion is that polarization
will be very useful, especially if the proton source is such that full
luminosity in the storage ring can be retained even after imposing cuts on the
originally accepted muons necessary for $P\gsim 0.4$ for each beam.

</DOC>
<DOC>
<DOCNO> 117821 </DOCNO>
A Young Globular Cluster in the Galaxy NGC 6946


  A globular cluster ~15 My old that contains 5x10^5 Msun of stars inside an 11
pc radius has been found in the nearby spiral galaxy NGC 6946, surrounded by
clouds of dust and smaller young clusters inside a giant circular bubble 300 pc
in radius. At the edge of the bubble is an arc of regularly-spaced clusters
that could have been triggered during the bubble's formation. The region is at
the end of a spiral arm, suggesting an origin by the asymmetric collapse of
spiral arm gas. The globular is one of the nearest examples of a cluster that
is similar to the massive old globulars in the Milky Way. We consider the
energetics of the bubble and possible formation mechanisms for the globular
cluster, including the coalescence of smaller clusters.

</DOC>
<DOC>
<DOCNO> 118989 </DOCNO>
A Self-Occulting Accretion Disk in the SW Sex Star DW UMa


  We present the ultraviolet spectrum of the SW Sex star and nova-like variable
DW UMa in an optical low state, as observed with the Space Telescope Imaging
Spectrograph on board the Hubble Space Telescope (HST). The data are well
described by a synthetic white dwarf (WD) spectrum with T_eff = 46,000 +/- 1000
K, log g = 7.60 +/- 0.15, v*sin(i) = 370 +/- 100 km/s and Z/Z_solar = 0.47 +/-
0.15. For this combination of T_eff and log g, WD models predict M_WD = 0.48
+/- 0.06 M_solar and R_WD = (1.27 +/- 0.18) * 10^9 cm. Combining the radius
estimate with the normalization of the spectral fit, we obtain a distance
estimate of d = 830 +/-150 pc.
  During our observations, DW UMa was approximately 3 magnitudes fainter in V
than in the high state. A comparison of our low-state HST spectrum to a
high-state spectrum obtained with the International Ultraviolet Explorer shows
that the former is much bluer and has a higher continuum level shortward of
1450 A. Since DW UMa is an eclipsing system, this suggests that an optically
thick accretion disk rim blocks our view of the WD primary in the high state.
If self-occulting accretion disks are common among the SW Sex stars, we can
account for (i) the preference for high-inclination systems within the class
and (ii) their V-shaped continuum eclipses. Moreover, even though the emission
lines produced by a self-obscured disk are generally still double-peaked, they
are weaker and narrower than those produced by an unobscured disk. This may
allow a secondary line emission mechanism to dominate and produce the
single-peaked, optical lines that are a distinguishing characteristic of the SW
Sex stars.

</DOC>
<DOC>
<DOCNO> 68440 </DOCNO>
Left-right asymmetries and exotic vector-boson discovery in


  By considering left-right (L-R) asymmetries we study the capabilities of
lepton colliders in searching for new exotic vector bosons. Specifically we
study the effect of a doubly charged bilepton boson and an extra neutral vector
boson appearing in a 3-3-1 model on the L-R asymmetries for the processes
$e^-e^-\to e^-e^-$, $\mu^-\mu^-\to\mu^-\mu^-$ and $e^-\mu^-\to e^-\mu^-$ and
show that these asymmetries are very sensitive to these new contributions and
that they are in fact powerful tools for discovery this sort of vector bosons.

</DOC>
<DOC>
<DOCNO> 12853 </DOCNO>
Ca0.85Sm0.15MnO3: A mixed antiferromagnet with unusual properties


  We investigated electrical and magnetic properties of the electron-doped
manganites Ca1-xSmxMnO3 (0<x<0.2). Our results indicate the possibility of
phase separation in electron doped manganites. The compounds with x = 0.13-0.15
show unusual difference between zero-field cooled and field-cooled
resistivities which are not observed in lower compositions. Our results suggest
that electronic phase separation alone is insufficient to understand the origin
of the resistivity irreversibilities.

</DOC>
<DOC>
<DOCNO> 117758 </DOCNO>
Frequency resolved spectroscopy of Cyg X-1: fast variability of the


  Using the RXTE/PCA data we study the fast variability of the reflected
emission in the soft spectral state of Cyg X-1 by means of Fourier frequency
resolved spectroscopy. We find that the rms amplitude of variations of the
reflected emission has the same frequency dependence as the primary radiation
down to time scales of <30-50 msec. This might indicate that the reflected flux
reproduces, with nearly flat response, variations of the primary emission. Such
behavior differs notably from the hard spectral state, in which variations of
the reflected flux are significantly suppressed in comparison with the primary
emission, on time scales shorter than ~0.5-1 sec. If related to the finite
light crossing time of the reflector, these results suggest that the
characteristic size of the reflector -- presumably an optically thick accretion
disk, in the hard spectral state is larger by a factor of >5-10 than in the
soft spectral state. Modeling the transfer function of the disk, we estimate
the inner radius of the accretion disk R_in~100R_g in the hard and R_in<10R_g
in the soft state for a 10M_sun black hole.

</DOC>
<DOC>
<DOCNO> 9213 </DOCNO>
Optimal coloured perceptrons


  Ashkin-Teller type perceptron models are introduced. Their maximal capacity
per number of couplings is calculated within a first-step
replica-symmetry-breaking Gardner approach. The results are compared with
extensive numerical simulations using several algorithms.

</DOC>
<DOC>
<DOCNO> 10295 </DOCNO>
Non-extensive statistical mechanics approach to fully developed


  We apply non-extensive methods to the statistical analysis of fully developed
turbulent flows. Probability density functions of velocity differences at
distance r obtained by extremizing the Tsallis entropies coincide well with
what is measured in turbulence experiments. We derive a set of relations
between the hyperflatness factors F_m and the non-extensitivity parameter q,
which can be used to directly extract the function q(r) from experimentally
measured structure functions. We comment on various non-extensive methods to
calculate the moment scaling exponents zeta_m.

</DOC>
<DOC>
<DOCNO> 117348 </DOCNO>
Studies of Low-Mass Star Formation with ALMA


  ALMA will revolutionize the study of star formation by providing a
combination of angular resolution and sensitivity that far exceeds that of
present instruments. I will focus on studies of relatively isolated cores that
are forming low-mass stars. There is a general paradigm for the formation of
such stars, and there are detailed theoretical predictions for the evolution of
the density and velocity fields for different assumptions about the initial
conditions. Because the theory is well developed, observational tests are
particularly revealing. The primary probes of physical conditions in these
regions are discussed and the sensitivity of ALMA to these probes is shown and
compared to the current state of the art. The consequences for the ALMA
requirements are discussed.

</DOC>
<DOC>
<DOCNO> 69349 </DOCNO>
Time Dependent Analysis of Decays $\Lambda_b\to \Lambda +D^0$ and


  The time-dependent analysis of the decays $\Lambda_b\to \Lambda +D^0(t)$ and
$\Lambda_b\to \Lambda +\bar{D}^0(t)$ is discussed. The effect of particle
mixing due to time evolution of $D^0$ and $\bar{D}^0$ on the observables for
these decays viz the branching ratio of decay widths and the asymmetry
parameters $\alpha ,\beta$ and $\gamma$ are analysed. It is shown that it is
possible to extract information about $(\Delta m/\Gamma)\sin \hat{\gamma}$ from
the experimental data for these observables. Here $\Delta
m=m_{D_1^0}-m_{D_2^0},\Gamma$ is the decay widths for $D^{\prime}s$ and
$\hat{\gamma}$ is the weak phase.

</DOC>
<DOC>
<DOCNO> 118665 </DOCNO>
Semi-Analytic Models for Dark Matter Halos


  Various analytic expressions have been proposed for the density profile of
dark matter halos. We consider six of these expressions for which the density
profile has a power-law fall-off rho proportional to r^{-3} at large radii and
a power-law cusp rho proportional to r^{-gamma} (gamma=0, 1/2, 1, 3/2) at small
radii. The phase-space distribution function for these models is calculated
assuming spherical symmetry and either an isotropic velocity dispersion tensor
or an anisotropic dispersion tensor of the type proposed by Osipkov and
Merritt. The differential energy distribution for these models is also derived.
Several applications are discussed including the analysis of dark matter search
experiments and the study of halo formation in a cosmological setting. Analytic
fitting formulae for some of the models are provided.

</DOC>
<DOC>
<DOCNO> 40232 </DOCNO>
$h\to \mu\tau$ at Hadron Colliders


  We study the observability for a lepton flavor-changing decay of a Higgs
boson $h\to \mu\tau$ at hadron colliders. Flavor-changing couplings of a Higgs
boson exist at tree level in models with multiple Higgs doublets. The
$h\mu\tau$ coupling is particularly motivated by the favorable intepretation of
$\nu_\mu-\nu_\tau$ oscillation. We find that at the Tevatron Run II the unique
$\mu\tau$ signature could serve as the Higgs discovery channel, surpassing
expectations for Higgs boson searches in the SM and in a large parameter region
of the MSSM. The sensitivity will be greatly improved at the LHC, beyond the
coverage at a muon collider Higgs factory.

</DOC>
<DOC>
<DOCNO> 9262 </DOCNO>
Magnetic Coherence in Cuprate Superconductors


  Recent inelastic neutron scattering (INS) experiments on
La$_{2-x}$Sr$_x$CuO$_4$ observed a {\it magnetic coherence effect}, i.e.,
strong frequency and momentum dependent changes of the spin susceptibility,
$\chi''$, in the superconducting phase. We show that this effect is a direct
consequence of changes in the damping of incommensurate antiferromagnetic spin
fluctuations due to the appearance of a d-wave gap in the fermionic spectrum.
Our theoretical results provide a quantitative explanation for the weak
momentum dependence of the observed spin-gap. Moreover, we predict {\bf (a)} a
Fermi surface in La$_{2-x}$Sr$_x$CuO$_4$ which is closed around $(\pi,\pi)$ up
to optimal doping, and {\bf (b)} similar changes in $\chi''$ for all cuprates
with an incommensurate magnetic response.

</DOC>
<DOC>
<DOCNO> 178626 </DOCNO>
Antiproton-deuteron annihilation at low energies


  Recent experimental studies of the antiproton-deuteron system at low energies
have shown that the imaginary part of the antiproton-deuteron scattering length
is smaller than the antiproton-proton one. Two- and three-body systems with
strong annihilation are investigated and a mechanism explaining this unexpected
relation between the imaginary parts of the scattering lengths is proposed.

</DOC>
<DOC>
<DOCNO> 39817 </DOCNO>
Measurement of Di-jet Cross-Sections in Photoproduction and Photon


  The production of hard di-jet events in photoproduction at HERA is dominated
by resolved photon processes in which a parton in the photon with momentum
fraction x_gamma is scattered from a parton in the proton. These processes are
sensitive to the quark and gluon content of the photon. The differential di-jet
cross-section dsigma/dlog(x_gamma) is presented here, measured in tagged
photoproduction at HERA using data taken with the H1 detector, corresponding to
an integrated luminosity of 7.2 pb^(-1). Using a restricted data sample at high
transverse jet energy, E_(T,jet)>6 GeV, the effective parton density
f_gamma,eff(x_gamma) = [q(x_gamma) + bar(q)(x_gamma) +9/4g(x_gamma)] in the
photon in leading order QCD is measured down to x_gamma=0.05 from which the
gluon density in the photon is derived.

</DOC>
<DOC>
<DOCNO> 71578 </DOCNO>
Local Realistic Theories and Quantum Mechanics for the two-neutral-kaon


  The predictions of local realistic theories for the observables concerning
the evolution of a $K^0\bar{K}^0$ quantum entangled pair (created in the decay
of the $\phi$-meson) are discussed. It is shown, in agreement with Bell's
theorem, that the most general local hidden-variable model fails in reproducing
the whole set of quantum-mechanical joint probabilities. We achieve these
conclusion by employing two different approaches. In a first one the local
realistic observables are deduced from the most general premises concerning
locality and realism, and Bell-like inequalities are not employed. The other
approach makes use of Bell's inequalities. Within the former scheme, under
particular conditions for the detection times, the discrepancy between quantum
mechanics and local realism for the time-dependent asymmetry turns out to be
not less than 20%. The same incompatibility can be made evident by means of a
Bell-type test by employing both Wigner's and (once properly normalized
probabilities are used) Clauser-Holt-Shimony-Holt's inequalities. Because of
the relatively low experimental accuracy, the data obtained by the CPLEAR
collaboration for the asymmetry parameter do not allow for a decisive test of
local realism. Such a test, both with and without the use of Bell's
inequalities, should be feasible in the future at the Frascati $\Phi$-factory.

</DOC>
<DOC>
<DOCNO> 11696 </DOCNO>
Conductance of the Single Electron Transistor for Arbitrary Tunneling


  We study the temperature and gate voltage dependence of the conductance of
the single electron transistor focusing on highly conducting devices. Electron
tunneling is treated nonperturbatively by means of path integral Monte Carlo
techniques and the conductance is determined from the Kubo formula. A
regularized singular value decomposition scheme is employed to calculate the
conductance from imaginary time simulation data. Our findings are shown to
bridge between available analytical results in the semiclassical and
perturbative limits and are found to explain recent experimental results in a
regime not accessible by earlier methods.

</DOC>
<DOC>
<DOCNO> 10921 </DOCNO>
Fate stochastic management and policy benchmark in 421, a popular game


  Using game and probability theories, I study the French popular game 421, a
perfect information stochastic stage game. The problem is to find strategies
maximizing the probability of some expected utility. I only solve a player's
round against providence, a problem of fate stochastic management: beyond the
backward induction solution, bounded complexity motivates heuristic policies.
For a unique goal utility, a simple optimal policy, ratchet, is obtained. Its
result probabilities are compiled and used, for arbitrary utilities, as the
logic of goal identification policies. Various policies appear, close to human
behavior, and are exactly evaluated by solving the Kolmogorov equation.

</DOC>
<DOC>
<DOCNO> 7688 </DOCNO>
Breaking a one-dimensional chain: fracture in 1 + 1 dimensions


  The breaking rate of an atomic chain stretched at zero temperature by a
constant force can be calculated in a quasiclassical approximation by finding
the localized solutions ("bounces") of the equations of classical dynamics in
imaginary time. We show that this theory is related to the critical cracks of
stressed solids, because the world lines of the atoms in the chain form a
two-dimensional crystal, and the bounce is a crack configuration in (unstable)
mechanical equilibrium. Thus the tunneling time, Action, and breaking rate in
the limit of small forces are determined by the classical results of Griffith.
For the limit of large forces we give an exact bounce solution that describes
the quantum fracture and classical crack close to the limit of mechanical
stability. This limit can be viewed as a critical phenomenon for which we
establish a Levanyuk-Ginzburg criterion of weakness of fluctuations, and
propose a scaling argument for the critical regime. The post-tunneling dynamics
is understood by the analytic continuation of the bounce solutions to real
time.

</DOC>
<DOC>
<DOCNO> 12767 </DOCNO>
Extensive eigenvalues in spin-spin correlations: a tool for counting


  We study the nature of the broken ergodicity in the low temperature phase of
Ising spin glass systems, using as a diagnostic tool the spectrum of
eigenvalues of the spin-spin correlation function. We show that multiple
extensive eigenvalues of the correlation matrix $C_{ij}\equiv< S_i S_j>$ occur
if and only if there is replica symmetry breaking. We support our arguments
with Exchange Monte-Carlo results for the infinite-range problem. Here we find
multiple extensive eigenvalues in the RSB phase for $N \agt 200$, but only a
single extensive eigenvalue for phases with long-range order but no RSB.
Numerical results for the short range model in four spatial dimensions, for
$N\le 1296$, are consistent with the presence of a single extensive eigenvalue,
with the subdominant eigenvalue behaving in agreement with expectations derived
from the droplet model. Because of the small system sizes we cannot exclude the
possibility of replica symmetry breaking with finite size corrections in this
regime.

</DOC>
<DOC>
<DOCNO> 118252 </DOCNO>
An eigenfunction method for particle acceleration at ultra-relativistic


  We adapt and modify the eigenfunction method of computing the power-law
spectrum of particles accelerated at a relativistic shock front via the
first-order Fermi process (Kirk, J.G., Schneider, P., Astrophysical Journal
315, 425 (1987)) to apply to shocks of arbitrarily high Lorentz factor. The
power-law index of accelerated particles undergoing isotropic small-angle
scattering at an ultrarelativistic, unmagnetized shock is found to be s=4.23
+/- 0.2 (where s=d\ln f/ d\ln p, with f the Lorentz-invariant phase-space
density and p the momentum), in agreement with the results of Monte-Carlo
simulations. We present results for shocks in plasmas with different equations
of state and for Lorentz factors ranging from 5 to infinity.

</DOC>
<DOC>
<DOCNO> 10270 </DOCNO>
Coarsened Lattice Model for Random Granular Systems


  In random systems consisting of grains with size distributions the transport
properties are difficult to explore by network models. However, the
concentration dependence of effective conductivity and its critical properties
can be considered within coarsened lattice model proposed that takes into
account information from experimentally known size histograms. For certain
classes of size distributions the specific local arrangements of grains can
induce either symmetrical or unsymmetrical critical behaviour at two threshold
concentrations. Using histogram related parameters the non-monotonic behaviour
of the conductor-insulator and conductor-superconductor threshold is
demonstrated.

</DOC>
<DOC>
<DOCNO> 120231 </DOCNO>
One Hundred Years of Observations of the Be Star HDE 245770 (the X-ray


  UBV observations of the X-ray binary system A0535+26/V725 Tau at the Crimean
Station of the Sternberg Astronomical Institute in 1980-1998 are presented.
Based on our and published data, we analyze the photometric history of the star
from 1898.

</DOC>
<DOC>
<DOCNO> 13638 </DOCNO>
Magneto infra-red absorption in high electronic density GaAs quantum


  Magneto infra-red absorption measurements have been performed in a highly
doped GaAs quantum well which has been lifted off and bonded to a silicon
substrate, in order to study the resonant polaron interaction. It is found that
the pinning of the cyclotron energy occurs at an energy close to that of the
transverse optical phonon of GaAs. This unexpected result is explained by a
model taking into account the full dielectric constant of the quantum well.

</DOC>
<DOC>
<DOCNO> 119921 </DOCNO>
Lyman alpha Transfer in a thick, dusty, and static medium


  We developed a Monte Carlo code that describes the resonant Lyman alpha line
transfer in an optically thick, dusty, and static medium. The code was tested
against the analytic formula derived by Neufeld (1990). We explain the line
transfer mechanism for a wide range of line center optical depths by tracing
histories of photons in the medium. We find that photons escape from the medium
by a series of wing scatterings, during which polarization may develop. We
applied our code to examine the amount of dust extinction around the Lyman
alpha in primeval galaxies. Brief discussions on the astrophysical application
of our work are presented.

</DOC>
<DOC>
<DOCNO> 11563 </DOCNO>
Thermodynamics of C incorporation on Si(100) from ab initio calculations


  We study the thermodynamics of C incorporation on Si(100), a system where
strain and chemical effects are both important. Our analysis is based on
first-principles atomistic calculations to obtain the important lowest energy
structures, and a classical effective Hamiltonian which is employed to
represent the long-range strain effects and incorporate the thermodynamic
aspects. We determine the equilibrium phase diagram in temperature and C
chemical potential, which allows us to predict the mesoscopic structure of the
system that should be observed under experimentally relevant conditions.

</DOC>
<DOC>
<DOCNO> 178542 </DOCNO>
Statistical Model Description of $K^+$ and $K^-$ Production between 1 -


  The excitation functions of $K^+$ and $K^-$ mesons in heavy ion collisions
are studied within a statistical model assuming chemical and thermal
equilibrium with exact strangeness conservation. At low incident energies the
associate production of kaons, i.e. the production of a K+ together with a
hyperon and the production of a K- together with a K+, implies specific
features: different threshold energies and different dependences of K+ and K-
yields on baryon number density. It is shown that the experimentally observed
equality of the $K^+$ and $K^-$ rates at energies $\sqrt{s} - \sqrt{s_{th}}
\leq 0$ is due to a crossing of the two excitation functions. Furthermore, the
independence of the $K^+$ to $K^-$ ratio on the number of participating
nucleons observed at 1 and 10 $A\cdot$GeV is consistent with this model.

</DOC>
<DOC>
<DOCNO> 178895 </DOCNO>
Production of isoscalar pion pairs in the pd -> 3He pi pi reaction near


  The production near threshold of isoscalar pion pairs in the pd -> 3He(pi
pi)^0 reaction is estimated in a two-step model which successfully describes
the production of eta, omega and eta' mesons. A virtual pion beam, generated
through an NN -> d pi reaction on one of the nucleons in the deuteron, produces
a second pion via a pi N -> pi pi N reaction on the other nucleon. Using the
same scale factor as for heavy meson production, the model reproduces the total
pi^0 pi^0 production rate determined at an excess energy of 37 MeV. There are
some indications in the data for a suppression of events with low pi pi masses,
as in the pi^- p -> pi^0 pi^0 n reaction, and this is confirmed within the
model. The model suggests that a significant fraction of the charged pion
production in the p d -> 3He pi^+ pi^- reaction at Q=70 MeV might be associated
with isoscalar pion pairs, though this does not explain the strong dependence
observed on the pi^+ pi^- relative momentum angle.

</DOC>
<DOC>
<DOCNO> 122671 </DOCNO>
Factor analysis of Galactic globular clusters on structural parameters


  Principal component method is used to study galactic globular clusters in 7-
and 8-axis space of structural parameters. It is shown that the manifold
properties of clusters with this set of parameters is determined mainly by two
independent factors. This result may be useful for the theory of formation and
evolution of clusters.

</DOC>
<DOC>
<DOCNO> 69664 </DOCNO>
The Effective Pressure of a Saturated Gluon Plasma


  The evolution of the gluon plasma produced with saturation initial conditions
is calculated via transport theory for nuclear collisions with 0.1 <sqrt(s) <10
A TeV. The effective longitudinal pressure is found to remain significantly
below the lattice QCD pressure with these initial conditions until the plasma
cools to near the confinement scale. The absolute value of the transverse
energy per unit of rapidity and its dependence on beam energy is shown to
provide a sensitive test of gluon saturation models since the fractional
transverse energy loss due to final state interactions is predicted to be much
smaller and exhibit a weaker energy dependence than nondissipative
hydrodynamics applied throughout the evolution.

</DOC>
<DOC>
<DOCNO> 70209 </DOCNO>
Screening corrections in DIS at low Q^2 and x


  In this investigation we present a detailed study of $\partial F_2/\partial
\ln Q^2$ which is supported by a coupled analysis of $J/\Psi$ photo and DIS
production. Both channels are directly proportional to $xG(x,Q^2)$, and as such
serve as excellent discriminators between different approaches and models.
 We then show that taking GRV98NLO as input and correcting it for SC, we can
reproduce the recent HERA data well. The calculation depends on one parameter
$R^2=8.5GeV^{-2}$ which is directly determined from the $J/\Psi$
photoproduction forward differential slope. With this input we obtain an
excellent fit to the $J/\Psi$ photo and DIS production data. Our calculations
made in the LLA of pQCD take into account the corrections implied by the real
part of the production amplitude, off diagonal (skewed) gluon distributions and
the Fermi motion of the charm quarks within the bound Charmonium system.

</DOC>
<DOC>
<DOCNO> 9273 </DOCNO>
A Personal List of Unsolved Problems Concerning Lattice Gases and


  I review recent results and unsolved problems concerning the hard-core
lattice gas and the q-coloring model (antiferromagnetic Potts model at zero
temperature). For each model, I consider its equilibrium properties
(uniqueness/nonuniqueness of the infinite-volume Gibbs measure, complex zeros
of the partition function) and the dynamics of local and nonlocal Monte Carlo
algorithms (ergodicity, rapid mixing, mixing at complex fugacity). These
problems touch on mathematical physics, probability, combinatorics and
theoretical computer science.

</DOC>
<DOC>
<DOCNO> 118409 </DOCNO>
CMB B-polarization to map the Large-scale Structures of the Universe


  We explore the possibility of using the B-type polarization of the CMB to map
the large-scale structures of the Universe taking advantage of the lens effects
on the CMB polarization. The functional relation between the B component with
the primordial CMB polarization and the line-of-sight mass distribution is
explicited. Noting that a sizeable fraction (at least 40%) of the dark halo
population which is responsible of this effect can also be detected in galaxy
weak lensing survey, we present statistical quantities that should exhibit a
strong sensitivity to this overlapping. We stress that it would be a sound test
of the gravitational instability picture, independent on many systematic
effects that may hamper lensing detection in CMB or galaxy survey alone.
Moreover we estimate the intrinsic cosmic variance of the amplitude of this
effect to be less than 8% for a 100, deg^2 survey with a 10' CMB beam. Its
measurement would then provide us with an original mean for constraining the
cosmological parameters, more particularly, as it turns out, the cosmological
constant Lambda.

</DOC>
<DOC>
<DOCNO> 40654 </DOCNO>
Rare K+ Decays from Experiment E787


  This paper presents the latest results from experiment E787, at Brookhaven
National Laboratory, on K+ -> pi nu/nubar and radiative K+ decays. The result
for K+ -> pi nu/nubar uses data collected in runs taken during 1995, 1996 and
1997. In addition, we discuss plans for future measurements of K+ -> pi
nu/nubar.

</DOC>
<DOC>
<DOCNO> 11945 </DOCNO>
Many-body diagrammatic expansion in a Kohn-Sham basis: implications for


  We formulate diagrammatic rules for many-body perturbation theory which uses
Kohn-Sham (KS) Green's functions as basic propagators. The diagram technique
allows to study the properties of the dynamic nonlocal exchange-correlation
(xc) kernel $f_{xc}$. We show that the spatial non-locality of $f_{xc}$ is
strongly frequency-dependent. In particular, in extended systems the
non-locality range diverges at the excitation energies. This divergency is
related to the discontinuity of the xc potential.

</DOC>
<DOC>
<DOCNO> 71322 </DOCNO>
The gluon content of the photon from di-jet production at the


  A study of di-jet measurements at a future photon collider is reported. The
sensitivity to extract the gluon distribution is discussed. The results are
compared with calculations for a linear e+e- collider.

</DOC>
<DOC>
<DOCNO> 178507 </DOCNO>
On dipole compression modes in nuclei


  Isoscalar dipole strength distributions in spherical medium- and heavy-mass
nuclei are calculated within random phase approximation (RPA) or quasiparticle
RPA. Different Skyrme-type interactions corresponding to incompressibilities in
the range 200 - 250 MeV are used. The results are discussed in comparison with
existing data on isoscalar giant dipole resonances. Two main issues are raised,
firstly the calculated giant resonance energies are somewhat higher than the
observed ones, and secondly a sizable fraction of strength is predicted below
20 MeV which needs to be experimentally confirmed.

</DOC>
<DOC>
<DOCNO> 152410 </DOCNO>
The geometry of W3 algebra: a twofold way for the rebirth of a symmetry


  The purpose of this note is to show that W3 algebras originate from an
unusual interplay between the breakings of the reparametrization invariance
under the diffemorphism action on the cotangent bundle of a Riemann surface. It
is recalled how a set of smooth changes of local complex coordinates on the
base space are collectively related to a background within a symplectic
framework. The power of the method allows to calculate explicitly some primary
fields whose OPEs generate the algebra as explicit functions in the
coordinates: this is achieved only if well defined conditions are satisfied,
and new symmetries emerge from the construction. Moreoverer, when primary
flelds are introduced outside of a coordinate description the W3 symmetry
byproducts acquire a good geometrical definition with respect to holomorphic
changes of charts.

</DOC>
<DOC>
<DOCNO> 12310 </DOCNO>
Intra-molecular origin of the fast relaxations observed in the Brillouin


  The Brillouin light scattering spectra of the o-terphenyl single crystal are
compared with those of the liquid and the glass phases. This shows: i) the
direct evidence of a fast relaxation at 5 GHz in both the single crystal and
the glass; ii) a similar temperature dependence for the attenuation of the
longitudinal sound waves in the single crystal and the glass; and iii) the
absence of coupling between the fast relaxation and the transverse acoustic
waves. These results allow us to assign such a relaxation to the coupling
between the longitudinal acoustic waves and intra-molecular vibrations, and
therefore to exclude any relationship between it and the glass transition.

</DOC>
<DOC>
<DOCNO> 84850 </DOCNO>
Some Comments on Wheeler De Witt Equation for Gravitational Collapse and


  We write the Hamiltonian for a gravitational spherically symmetric scalar
field collapse with massive scalar field source, and we discuss the application
of Wheeler De Witt equation as well as the appearence of time in this context.
Using an Ansatz for Wheeler De Witt equation, solutions are discussed including
the appearence of time evolution.

</DOC>
<DOC>
<DOCNO> 7657 </DOCNO>
Time Dependent Effects and Transport Evidence for Phase Separation in


  The ground state of La_{1-x}Ca_{x}MnO_{3} changes from a ferromagnetic
metallic to an antiferromagnetic charge-ordered state as a function of Ca
concentration at x ~ 0.50. We present evidence from transport measurements on a
sample with x = 0.50 that the two phases can coexist, in agreement with other
observations of phase separation in these materials. We also observe that, by
applying and then removing a magnetic field to the mainly charge-ordered state
at some temperatures, we can "magnetically anneal" the charge order, resulting
in a higher zero-field resistivity. We also observe logarithmic time dependence
in both resistivity and magnetization after a field sweep at low temperatures.

</DOC>
<DOC>
<DOCNO> 121892 </DOCNO>
Model Spectra of Rotation Powered Pulsars in the INTEGRAL Range


  The energy range of IBIS is a promising ground for testing mutual relations
of distinct components expected in the spectra of high-energy radiation from
rotation powered pulsars. According to some polar-cap models two such
components - due to curvature and synchrotron emission - may contribute
comparable amounts of power between 15 keV and 10 MeV (Rudak & Dyks 1999).
Zhang & Harding (2000) argued recently for the inclusion of a third possible
component, due to inverse Compton scattering (ICS) of soft thermal photons on
secondary $\epm$-pairs. Here we present the results of Monte Carlo calculations
of all three spectral components within a polar-cap model which allows for
interactions of relativistic particles with the soft photons coming from the
pulsar surface. For teragauss pulsars with the surface temperature of a few
times 10^5 K the ICS component dominates the spectrum in the energy range below
10 MeV, and thus its presence increases the ratio of X-ray to gamma-ray
luminosity (in comparison to the models ignoring the ICS on secondary
$\epm$-pairs) to a level observed in the Vela pulsar.

</DOC>
<DOC>
<DOCNO> 71374 </DOCNO>
A Variable Flavour Number Scheme for Charged Current Heavy Flavour


  The Thorne-Roberts variable flavour number scheme (VFNS) for heavy quarks is
presented in detail for the specific case of charged current DIS. As in neutral
current DIS this provides a smooth extrapolation from the fixed flavour number
scheme (FFNS) appropriate at low $Q^2$ to the zero-mass variable flavour number
scheme (ZM-VFNS) appropriate as $Q^2 \to \infty$, and differs from alternative
versions of a VFNS by the definition of the coefficient functions at each
order, and the strict ordering of the expansion in $\alpha_S$. However, there
are subtle differences from the neutral current case which are addressed here.
We discuss both the LO and NLO expressions, the latter unfortunately requiring
some (minimal) modelling due to the current lack of some necessary ${\cal
O}(\alpha^2_S)$ FFNS coefficient functions.

</DOC>
<DOC>
<DOCNO> 68163 </DOCNO>
Neutrino decay and long base-line oscillation experiments


  Considering neutrinos as time-like leptons one may estimate the three-body
decay probability of muon neutrinos in long base-line accelerator experiments.
In the extreme assumption of time-space symmetry the absolute value of the
transcendent mass of a muon neutrino is equal to the rest mass of its bradyon
partner which is, however, strongly suppressed in measurements using the weak
interaction. This decay, neglecting small oscillations or other effects, leads
to a strong dependence of the effect on the base-line distance. As a result,
few hundred kilometre long baseline experiments might hardly see muon-like
events. Total rates of electron-like events from three-body decay are
calculated for K2K, MINOS and ICARUS. Shorter base-line experiments able to see
clearly the effect of muon neutrino decay are very promissing component of long
base-line projects.

</DOC>
<DOC>
<DOCNO> 120492 </DOCNO>
The BeppoSAX HELLAS survey: on the nature of faint hard X-ray selected


  The BeppoSAX 4.5-10 keV High Energy Large Area Survey has covered about 80
square degrees of sky down to a flux of F(5-10keV)~5E-14 cgs. Optical
spectroscopic identification of about half of the sources in the sample (62)
shows that many (~50%) are highly obscured AGN, in line with the predictions of
AGN synthesis models for the hard X-ray background (XRB, see e.g. Comastri et
al. 1995). The X-ray data, complemented by optical, near-IR and radio
follow-up, indicate that the majority of these AGN are ``intermediate''
objects, i.e. type 1.8-1.9 AGN,`red' quasars, and even a few broad line, blue
continuum quasars, obscured in X-rays by columns of the order of
logNH=22.5-23.5 cm-2, but showing a wide dispersion in optical extinction. The
optical and near-IR photometry of the obscured objects are dominated by galaxy
starlight, indicating that a sizeable fraction of the accretion power in the
Universe may actually have been missed in optical color surveys. This also
implies that multicolor photometry techniques may be efficiently used to assess
the redshift of the hard X-ray selected sources.

</DOC>
<DOC>
<DOCNO> 178654 </DOCNO>
Near threshold Lambda and Sigma production in pp collisions


  A model calculation for the reactions $pp\to p\Lambda K^+$ and $pp\to N\Sigma
K$ near their thresholds is presented. It is argued that the experimentally
observed strong suppression of $\Sigma^0$ production compared to $\Lambda$
production at the same excess energy could be due to a destructive interference
between the $\pi$ and $K$ exchange contributions in the reaction $pp\to
p\Sigma^0 K^+$. Predictions for $pp\to p\Sigma^+ K^0$ and $pp\to n\Sigma^+ K^+$
are given.

</DOC>
<DOC>
<DOCNO> 102324 </DOCNO>
Computing the rational torsion of an elliptic curve using Tate normal


  It is a classical result (apparently due to Tate) that all elliptic curves
with a torsion point of order n ($4 \leq n \leq 10$, or n = 12) lie in a
one-parameter family. However, this fact does not appear to have been used ever
for computing the torsion of an elliptic curve. We present here a extremely
down-to-earth algorithm using the existence of such a family.

</DOC>
<DOC>
<DOCNO> 101696 </DOCNO>
On our paper `Almost Free Splitter', a correction


  Let R be a subring of Q and recall from math.LO/9910161 that an R-module G is
a splitter if Ext_R(G,G)=0. We correct the statement of Main Theorem 1.5 in
math.LO/9910161. Assuming CH any aleph_1$-free splitter of cardinality aleph_1
is free over its nucleus as shown in math.LO/9910161. Generally these modules
are very close to being free as explained below. This change follows from
math.LO/9910161 and is due to an incomplete proof (noticed thanks to Paul
Eklof) in the first section of math.LO/9910161. Assuming the negation of CH, in
Shelah [Sh:F417] (work in progress) it will be shown that under Martin's axiom
these splitters are free indeed. However there are models of set theory having
non-free aleph_1-free splitter of cardinality aleph_1.

</DOC>
<DOC>
<DOCNO> 8996 </DOCNO>
Burst dynamics during drainage displacements in porous media:


  We investigate the burst dynamics during drainage going from low to high
injection rate at various fluid viscosities. The bursts are identified as
pressure drops in the pressure signal across the system. We find that the
statistical distribution of pressure drops scales according to other systems
exhibiting self-organized criticality. The pressure signal was calculated by a
network model that properly simulates drainage displacements. We compare our
results with corresponding experiments.

</DOC>
<DOC>
<DOCNO> 12883 </DOCNO>
Anisotropic conductivity in superconducting NCCO


  The low temperature behaviour of the in-plane and c-axis conductivity of
electron-doped cuprates like NCCO is examined; it is shown to be consistent
with an isotropic quasiparticle scattering rate and an anisotropic interlayer
hopping parameter which is non-zero for planar momenta along the direction of
the d$_{x^2-y^2}$ order parameter nodes. Based on these hypotheses we find that
both, the in-plane and the c-axis conductivity, vary linearly with temperature,
in agreement with experimental data at millimiter-wave frequencies.

</DOC>
<DOC>
<DOCNO> 120680 </DOCNO>
The detection of oxygen in the low-density intergalactic medium


  The abundances of metals in the intergalactic medium (IGM) can be used to
constrain the amount of star formation at high redshift and the spectral shape
of the ionizing background radiation. For both purposes it is essential to
measure the abundances in regions of low density, away from local sources of
metals and ionizing photons. Here we report the first detection of OVI in the
low-density IGM at high redshift. We perform a pixel-by-pixel search for OVI
absorption in eight high quality quasar spectra spanning the redshift range z =
2.0-4.5. At 2 ~< z ~< 3, we clearly detect OVI in the form of a positive
correlation between the HI Ly-alpha optical depth and the optical depth in the
corresponding OVI pixel, down to an HI optical depth of 0.1. This is an order
of magnitude lower in HI optical depth than the best CIV measurements can probe
and constitutes the first clear detection of metals in underdense gas. The
non-detection of OVI at z > 3 is consistent with the enhanced photoionization
from a hardening of the UV background below z ~ 3 but could also be caused by
the high level of contamination from Ly series lines.

</DOC>
<DOC>
<DOCNO> 39966 </DOCNO>
D0-anti-D0 Mixing and Rare Decays


  Current status of charm mixing search, lifetime difference measurement and
rare decay search are reported. The best upper limit at 95% CL for mixing is
reported from the CLEO collaboration. E791 has reported lifetime difference
measurement and results of rare decay searches. Rare decay searches of the
FOCUS collaboration are in progress and their sensitivities to branching ratios
are at the level of a few x 10^{-6}.

</DOC>
<DOC>
<DOCNO> 117948 </DOCNO>
Predictions on the number of variable stars for the GAIA space mission


  Future space and ground-based survey programmes will produce an impressive
amount of photometric data. The GAIA space mission will map the complete sky
down to mag V=20 and produce time series for about 1 billion stars. Survey
instruments as the International Liquid Mirror Telescope will observe slices of
the sky down to magnitude V=23. In both experiments, the opportunity exists to
discover a huge amount of variable stars. A prediction of the expected total
number of variable stars and the number of variables in specific subgroups is
given.

</DOC>
<DOC>
<DOCNO> 11605 </DOCNO>
Magnetization of Mn_12 Ac in a slowly varying magnetic field: an ab


  Beginning with a Heisenberg spin Hamiltonian for the manganese ions in the
Mn_12 Ac molecule, we find a number of low-energy states of the system. We use
these states to solve the time-dependent Schrodinger equation and find the
magnetization of the molecule in the presence of a slowly varying magnetic
field. We study the effects of the field sweep rate, fourth order anisotropic
spin interactions and a transverse field on the weights of the different states
as well as the magnetization steps which are known to occur in the hysteresis
plots in this system. We find that the fourth order term and a slow field sweep
rate are crucial for obtaining prominent steps in magnetization in the
hysteresis plots.

</DOC>
<DOC>
<DOCNO> 170266 </DOCNO>
Numerical Experiments on The Capacity of Quantum Channel with Entangled


  The capacity of quantum channel with product input states was formulated by
the quantum coding theorem. However, whether entangled input states can enhance
the quantum channel is still open. It turns out that this problem is reduced to
aspecial case of the more general problem whether the capacity of product
quantum channel exhibits additivity. In the present study, we apply one of the
quantum Arimoto-Blahut type algorithms to the latter problem. The results
suggest that the additivity of product quantum channel capacity always holds
and that entangled input states cannot enhance the quantum channel capacity.

</DOC>
<DOC>
<DOCNO> 69079 </DOCNO>
The role of the input in Roy's equations for pion-pion scattering


  The Roy equations determine the S- and P-wave pion-pion phase shifts on a low
energy interval. They allow the derivation of threshold parameters from
experimental data. We examine the solutions of these equations that are in the
neighborhood of a given solution by means of a linearization procedure. An
updated survey of known results on the dimension of the manifold of solutions
is presented. The solution is unique for a low energy interval with upper end
at 800 MeV. We determine its response to small variations of the input: S-wave
scattering lengths and absorptive parts above 800 MeV. We confirm the existence
of a universal curve of solutions in the plane of the S-wave scattering lengths
and provide a control of the decrease of the influence of the input absorptive
parts with increasing energy. A general result on the suppression of unphysical
singularities at the upper end of the low energy interval is established and
its practical implications are discussed.

</DOC>
<DOC>
<DOCNO> 84556 </DOCNO>
Fuchsian analysis of singularities in Gowdy spacetimes beyond


  Fuchsian equations provide a way of constructing large classes of spacetimes
whose singularities can be described in detail. In some of the applications of
this technique only the analytic case could be handled up to now. This paper
develops a method of removing the undesirable hypothesis of analyticity. This
is applied to the specific case of the Gowdy spacetimes in order to show that
analogues of the results known in the analytic case hold in the smooth case. As
far as possible the likely strengths and weaknesses of the method as applied to
more general problems are displayed.

</DOC>
<DOC>
<DOCNO> 119160 </DOCNO>
ISO-SWS observations of pure rotational water absorption lines toward


  First detections of thermal water vapor absorption lines have been made
toward Orion IRc2 using the Short Wavelength Spectrometer (SWS) on board the
Infrared Space Observatory (ISO). Grating spectra covering wavelengths 25-45
micron yield 19 pure rotational lines, originating from energy levels 200-750 K
above ground. Fabry-Perot spectra of 5 transitions resolve the line profiles
and reveal the water gas kinematics. The fact that all lines are seen in
absorption is in striking contrast with data from the ISO Long Wavelength
Spectrometer (LWS), where the water lines appear in emission. At least one line
displays a P-Cygni type profile, which suggests that the water is located in an
expanding shell centered on or near IRc2. The expansion velocity is 18 km per
second, in agreement with the value inferred from water maser observations by
Genzel et al. (1981). Because the continuum is intense and likely formed in or
near the water-containing gas, the excitation of the observed transitions is
dominated by radiative processes. A simple, generalised curve-of-growth method
is presented and used to analyze the data. A mean excitation temperature of 72
K and a total water column density of 1.5e18 molecules per cm squared are
inferred, each with an estimated maximum uncertainty of 20%. Combined with the
molecular hydrogen column density derived from ISO observations of the pure
rotational lines, and an assumed temperature of 200-350 K, the inferred water
abundance is 2e-4 to 5e-4 in the warm shocked gas. This abundance is similar to
that found recently by Harwit et al. (1998) toward Orion using data from the
LWS, but higher than that found for most other shocked regions by, for example,
Liseau et al. (1996).

</DOC>
<DOC>
<DOCNO> 119438 </DOCNO>
An Interpretation of the Evidence for TeV Emission from Gamma-Ray Burst


  The Milagrito collaboration recently reported evidence for emission of very
high energy gamma-rays in the TeV range from one of the BATSE GRBs, GRB
970417a. Here I discuss possible interpretations of this result. Taking into
account the intergalactic absorption of TeV gamma-rays by the cosmic infrared
background, I found that the detection rate (one per 54 GRBs observed by the
Milagrito) and energy fluence can be consistently explained with the redshift
of this GRB at z \sim 0.7 and the isotropic total energy in the TeV range,
E_{TeV, iso} >~ 10^{54} erg. This energy scale is not unreasonably large, but
interestingly similar to the maximum total GRB energy observed to date, in the
sub-MeV range for GRB 990123. On the other hand, the energy emitted in the
ordinary sub-MeV range becomes E_{MeV, iso} \sim 10^{51} erg for the GRB
970417a, which is much smaller than the total energy in the TeV range by a
factor of about 10^3. I show that the proton-synchrotron model of GRBs provides
a possible explanation for these observational results. I also discuss some
observational signatures expected in the future experiments from this model.

</DOC>
<DOC>
<DOCNO> 100349 </DOCNO>
A Characterization of Completely-Positive Trace-Preserving Maps on 2x2


  This paper has been superseded by quant-ph/0101003.

</DOC>
<DOC>
<DOCNO> 70016 </DOCNO>
Meson-Meson Scattering in the Quark Model: Spin Dependence and Exotic


  We apply a quark interchange model to spin-dependent and exotic meson-meson
scattering. The model includes the complete set of standard quark model forces,
including OGE spin-orbit and tensor and scalar confinement spin-orbit.
Scattering amplitudes derived assuming SHO and Coulomb plus linear plus
hyperfine meson wavefunctions are compared. In I=2 pi pi we find approximate
agreement with the S-wave phase shift from threshold to 1.5 GeV, where we
predict an extremum that is supported by the data. Near threshold we find rapid
energy dependence that may reconcile theoretical estimates of small scattering
lengths with experimental indications of larger ones based on extrapolation of
measurements at moderate kpi^2. In PsV scattering we find that the quark-quark
L*S and T forces map into L*S and T meson-meson interactions, and the P-wave
L*S force is large. Finally we consider scattering in J^PC-exotic channels, and
note that some of the Deck effect mechanisms suggested as possible nonresonant
origins of the pi_1(1400) signal are not viable in this model.

</DOC>
<DOC>
<DOCNO> 120711 </DOCNO>
Measurement of air shower cores to study the cosmic ray composition in


  Since 1996, a hybrid experiment consisting of an emulsion chamber and a burst
detector array and the Tibet-II air shower array has been operated at
Yangbajing (4300 m above sea level) in Tibet. This experiment can detect
air-shower cores, called burst events, accompanied by air showers in excess of
about 100 TeV. Using the burst event data observed by this experiment, we
discuss the primary cosmic ray composition around the knee in comparison with
the Monte Carlo simulations. In this paper, we show that all the features of
burst events are wholly compatible with the heavy enriched composition in the
knee energy region.

</DOC>
<DOC>
<DOCNO> 84810 </DOCNO>
Quasi-circular Orbits for Spinning Binary Black Holes


  Using an effective potential method we examine binary black holes where the
individual holes carry spin. We trace out sequences of quasi-circular orbits
and locate the innermost stable circular orbit as a function of spin. At large
separations, the sequences of quasi-circular orbits match well with
post-Newtonian expansions, although a clear signature of the simplifying
assumption of conformal flatness is seen. The position of the ISCO is found to
be strongly dependent on the magnitude of the spin on each black hole. At close
separations of the holes, the effective potential method breaks down. In all
cases where an ISCO could be determined, we found that an apparent horizon
encompassing both holes forms for separations well inside the ISCO.
Nevertheless, we argue that the formation of a common horizon is still
associated with the breakdown of the effective potential method.

</DOC>
<DOC>
<DOCNO> 151407 </DOCNO>
Tachyon potentials, star products and universality


  We develop an efficient recursive method to evaluate the tachyon potential
using the relevant universal subalgebra of the open string star algebra. This
method, using off-shell versions of Virasoro Ward identities, avoids explicit
computation of conformal transformations of operators and does not require a
choice of background. We illustrate the procedure with a pedagogic computation
of the level six tachyon potential in an arbitrary gauge, and the evaluation of
a few simple star products. We give a background independent construction of
the so-called identity of the star algebra, and show how it fits into family of
string fields generating a commutative subalgebra.

</DOC>
<DOC>
<DOCNO> 69084 </DOCNO>
Thermal Equilibrium and Non-uniform Longitudinal Flow in Relativistic


  A model with non-uniform flow in the longitudinal direction is proposed for
the relativistic heavy-ion collisions and compared with the 14.6 A GeV/c Si-Al
and 10.8 A GeV/c Au-Au collision data. The stronger influence of transparency
on the distribution of heavier produced particles and the larger stopping in
the heavier collision system are accounted for by using a new geometrical
parameterization picture. The central dips in the proton and deuteron rapidity
distributions for Si-Al collision are reproduced.

</DOC>
<DOC>
<DOCNO> 12196 </DOCNO>
Rates of convergence of nonextensive statistical distributions to Levy


  The Levy-type distributions are derived using the principle of maximum
Tsallis nonextensive entropy both in the full and half spaces. The rates of
convergence to the exact Levy stable distributions are determined by taking the
N-fold convolutions of these distributions. The marked difference between the
problems in the full and half spaces is elucidated analytically. It is found
that the rates of convergence depend on the ranges of the Levy indices. An
important result emerging from the present analysis is deduced if interpreted
in terms of random walks, implying the dependence of the asymptotic long-time
behaviors of the walks on the ranges of the Levy indices if N is identified
with the total time of the walks.

</DOC>
<DOC>
<DOCNO> 178814 </DOCNO>
Low-Spin Spectroscopy of 50Mn


  The data on low spin states in the odd-odd nucleus 50Mn investigated with the
50Cr(p,ngamma)50Mn fusion evaporation reaction at the FN-TANDEM accelerator in
Cologne are reported. Shell model and collective rotational model
interpretations of the data are given.

</DOC>
<DOC>
<DOCNO> 169893 </DOCNO>
Fast quantum gates for neutral atoms


  We propose several schemes for implementing a fast two-qubit quantum gate for
neutral atoms with the gate operation time much faster than the time scales
associated with the external motion of the atoms in the trapping potential. In
our example, the large interaction energy required to perform fast gate
operations is provided by the dipole-dipole interaction of atoms excited to
low-lying Rydberg states in constant electric fields. A detailed analysis of
imperfections of the gate operation is given.

</DOC>
<DOC>
<DOCNO> 80593 </DOCNO>
Perturbative Renormalization Factors of Baryon Number Violating


  We calculate one-loop renormalization factors of three-quark operators, which
appear in the low energy effective Lagrangian of the nucleon decay, for
$O(a)$-improved quark action and gauge action including six-link loops. This
calculation is required to predict the hadronic nucleon decay matrix elements
in the continuum regularization scheme using lattice QCD. We present detailed
numerical results of the one-loop coefficients for general values of the clover
coefficients employing the several improved gauge actions in the Symanzik
approach and in the Wilson's renormalization group approach. The magnitudes of
the one-loop coefficients for the improved gauge actions show sizable reduction
compared to those for the plaquette action.

</DOC>
<DOC>
<DOCNO> 118535 </DOCNO>
The vertical extent and kinematics of the HI in NGC 2403


  The neutral hydrogen line profiles along the major axis of the nearby spiral
galaxy NGC 2403 show a wing towards the sytemic velocity. This asymmetry can be
explained with the presence of an abnormally thick HI disk (FWHM ~ 5 kpc) or
with a two-component structure: a thin disk and a slowly rotating, thicker (1-3
kpc) HI layer. The latter model gives a better representation of the
observations. These results throw a new light on the disk-halo connection. In
particular, the decrease of rotational velocity with height above the plane may
be the result of a galactic fountain flow. A vertically extended, slowly
rotating HI layer may be common among spiral galaxies with high levels of star
formation.

</DOC>
<DOC>
<DOCNO> 101608 </DOCNO>
A new parabolic flow in Kaehler manifolds


  In this paper, we introduce a new parabolic equation on K\"ahler manifolds.
The static point of this flow is related to the existence of a lower bound of
the Mabuchi energy. In this paper, we prove the flow always exists for all
times for any initial smooth data. Further more, if the initial metric has
non-negative bisectional curvature, we prove the flow converges to a static
metric eventually.

</DOC>
<DOC>
<DOCNO> 118816 </DOCNO>
First Results from the Large Area Lyman Alpha Survey


  We report on a new survey for z=4.5 Lyman alpha sources, the Large Area Lyman
Alpha (LALA) survey. Our survey achieves an unprecedented combination of volume
and sensitivity by using narrow-band filters on the new 8192x8192 pixel CCD
Mosaic Camera at the 4 meter Mayall telescope of Kitt Peak National
Observatory.
  Well-detected sources with flux and equivalent width matching known high
redshift Lyman alpha galaxies (i.e., observed equivalent width above 80
Angstroms and line+continuum flux between 2.6e-17 and 5.2e-17 erg/cm^2/sec in
an 80 Angstrom filter) have an observed surface density corresponding to 11000
+- 700 per square degree per unit redshift at z=4.5. Spatial variation in this
surface density is apparent on comparison between counts in 6561 and 6730
Angstrom filters.
  Early spectroscopic followup results from the Keck telescope included three
sources meeting our criteria for good Lyman alpha candidates. Of these, one is
confirmed as a z=4.52 source, while another remains consistent with either
z=4.55 or z=0.81. We infer that 30 to 50% of our good candidates are bona fide
Lyman alpha emitters, implying a net density of about 4000 Lyman alpha galaxies
per square degree per unit redshift.

</DOC>
<DOC>
<DOCNO> 99281 </DOCNO>
Lu Qi-Keng's Problem


  This expository article, intended to be accessible to students, surveys
results about the presence or absence of zeroes of the Bergman kernel function
of a bounded domain in C^n. Six open problems are stated.
  The article is based on a lecture at the third Korean several complex
variables symposium held at the Global Analysis Research Center at Seoul
National University in December 1998.

</DOC>
<DOC>
<DOCNO> 178516 </DOCNO>
Quark Condensate in the Deuteron


  We study the changes produced by the deuteron on the QCD quark condensate by
means the Feynman-Hellmann theorem and find that the pion mass dependence of
the pion-nucleon coupling could play an important role. We also discuss the
relation between the many body effect of the condensate and the meson exchange
currents, as seen by photons and pions. For pion probes, the many-body term in
the physical amplitude differs significantly from that of soft pions, the one
linked to the condensate. Thus no information about the many-body term of the
condensate can be extracted from the pion-deuteron scattering length. On the
other hand, in the Compton amplitude, the relationship with the condensate is a
more direct one.

</DOC>
<DOC>
<DOCNO> 121916 </DOCNO>
Chaotic Mixing in Galactic Dynamics


  This talk summarises what is currently understood about the phenomenon that
has come to be known as {\it chaotic mixing}. The first part presents a concise
statement as to what chaotic mixing actually is, and then explains why it
should be important in galactic dynamics. The second discusses in detail what
is currently known, describing the manifestations of chaotic mixing both for
flows in time-independent Hamiltonian systems and for systems subjected to
comparatively weak time-dependent perturbations. The third part discusses what
one might expect if one were to allow for a strongly time-dependent potential,
including possible implications for violent relaxation.

</DOC>
<DOC>
<DOCNO> 85322 </DOCNO>
Perturbations of brane worlds


  We consider cosmological models where the universe, governed by Einstein's
equations, is a piece of a five dimensional double-sided anti-de Sitter
spacetime (that is, a "$Z_2$-symmetric bulk") with matter confined to its four
dimensional Robertson-Walker boundary or "brane". We study the perturbations of
such models. We use conformally minkowskian coordinates to disentangle the
contributions of the bulk gravitons and of the motion of the brane. We find the
restrictions put on the bulk gravitons when matter on the brane is taken to be
a scalar field and we solve in that case the brane perturbation equations.

</DOC>
<DOC>
<DOCNO> 80826 </DOCNO>
Comparative Benchmarks of full QCD Algorithms


  We report performance benchmarks for several algorithms that we have used to
simulate the Schr"odinger functional with two flavors of dynamical quarks. They
include hybrid and polynomial hybrid Monte Carlo with preconditioning. An
appendix describes a method to deal with autocorrelations for nonlinear
functions of primary observables as they are met here due to reweighting.

</DOC>
<DOC>
<DOCNO> 118369 </DOCNO>
A Sample of 669 Ultra Steep Spectrum Radio Sources to Find High Redshift


  Since radio sources with Ultra Steep Spectra (USS; alpha <~ -1.30;
S~nu^alpha) are efficient tracers of high redshift radio galaxies (HzRGs), we
have defined three samples of such USS sources using the recently completed
WENSS, TEXAS, MRC, NVSS and PMN radio-surveys. Our combined sample contains 669
sources with S_1400 > 10 mJy and covers virtually the entire sky outside the
Galactic plane (|b|>15). For our 2 largest samples, covering declination > -35,
we selected only sources with angular sizes Theta < 1'. For 410 sources, we
present radio-maps with 0.3" to ~5" resolution from VLA and ATCA observations
or from the FIRST survey, which allows the optical identification of these
radio sources. We find that the spectral index distribution of 143,000 sources
from the WENSS and NVSS consists of a steep spectrum galaxy and a flat spectrum
quasar population, with the relative contribution of flat spectrum sources
doubling from S_1400 >0.1 Jy to S_1400 >2.5 Jy. The identification fraction of
our USS sources on the POSS (R <~ 20) is as low as 15%, independent of spectral
index alpha < -1.30. We further show that 85% of the USS sources that can be
identified with an X-ray source are probably contained in galaxy clusters, and
that alpha < -1.6 sources are excellent Galactic pulsar candidates, because the
percentage of these sources is four times higher in the Galactic plane. Our
sample has been constructed to start an intensive campaign to obtain a large
sample of high redshift objects (z>3) that is selected in a way that does not
suffer from dust extinction or any other optical bias [abridged].

</DOC>
<DOC>
<DOCNO> 40278 </DOCNO>
Hadronic Structure Functions


  Experimental results on hadronic structures are discussed in view of our
physics understanding. Achievements and challenges are noted.

</DOC>
<DOC>
<DOCNO> 84091 </DOCNO>
Analytic treatment of black-hole gravitational waves at the


  We study the Regge-Wheeler and Zerilli equations (RWE and ZE) at the
`algebraically special frequency' $\Omega$, where these equations admit an
exact solution (elaborated here), generating the SUSY relationship between
them. The physical significance of the SUSY generator and of the solutions at
$\Omega$ in general is elucidated as follows. The RWE has no (quasinormal or
total-transmission) modes at all; however, $\Omega$ is nonetheless `special' in
that (a) for the outgoing wave into the horizon one has a `miraculous'
cancellation of a divergence expected due to the exponential potential tail,
and (b) the branch-cut discontinuity at $\omega=\Omega$ vanishes in the
outgoing wave to infinity. Moreover, (a) and (b) are related. For the ZE, its
only mode is the-inverse-SUSY generator, which is at the same time a
quasinormal mode_and_ a total-transmission mode propagating to infinity. The
subtlety of these findings (of general relevance for future study of the
equations on or near the negative imaginary $\omega$-axis) may help explain why
the situation has sometimes been controversial. For finite black-hole rotation,
the algebraically special modes are shown to be totally transmitting, and the
implied singular nature of the Schwarzschild limit is clarified. The analysis
draws on a recent detailed investigation of SUSY in open systems
[math-ph/9909030].

</DOC>
<DOC>
<DOCNO> 117397 </DOCNO>
Distribution functions for evolved stars in the inner galactic Plane


  We present dynamical distribution functions for evolved stars in the inner
galactic plane. We use an axisymmetric, two-component Stackel potential that
satisfies recent constraints on the galactic potential, amongst others a
slightly declining local rotation curve. We show that this potential is
adequate to model stellar-kinematic samples with radial extent ranging from
\~100 pc to ~5 kpc in the Galaxy. The two-integral model that gives the best fit
to the first three projected moments provides a very good global representation
of the data but fails to reproduce the central dispersion, the central apparent
scaleheight and the cylindrical rotation at intermediate longitudes. All these
features are fitted well by a three--integral model. We discuss various
properties of the 2I- and 3I models and the implications for galactic
structure. A somewhat thicker disk component is needed to explain the
distribution of older AGB stars in the plane; this component also fits the
kinematics at higher latitudes better. We find that the Disk and the Bulge, as
traced by AGB stars, are very similar dynamically and could well be one and the
same component. There is a dynamically distinct component in the inner 100 pc
of the Bulge, however.

</DOC>
<DOC>
<DOCNO> 101926 </DOCNO>
Neutrosophy


  Neutrosophy is a new branch of philosophy which studies the origin, nature,
and scope of neutralities, as well as their interactions with different
ideational spectra.

</DOC>
<DOC>
<DOCNO> 71202 </DOCNO>
Combined recoil and threshold resummation for hard scattering cross


  We discuss the simultaneous resummation of threshold and recoil enhancements
to partonic cross sections due to soft radiation. Our method is based on a
refactorization of the parton cross section near its partonic threshold. It
avoids double counting, conserves the flow of partonic energy, and reproduces
either threshold or recoil resummation when the other enhancements are
neglected.

</DOC>
<DOC>
<DOCNO> 120561 </DOCNO>
Hubble Space Telescope Observations of the Planetary Nebula K648 in the


  We have obtained observations of the planetary nebula K648 in the Galactic
globular cluster M15 with the Hubble Space Telescope's WFPC2 camera, covering
an interval of 7 days. The frames provide both time-sampled broad-band
photometry of the central star and high-resolution images of the nebula in the
light of H-alpha, [OIII], and [NII]. In the deep narrow-band images, K648 is a
fairly typical double-shelled elliptical, but with a bright arc at one end of
the major axis that is especially prominent in [NII]; this feature is probably
a collection of FLIERs. The nebula is surrounded by a faint, smooth elliptical
halo, which appears undisturbed by any interaction with the interstellar
medium. Adopting Teff = 40,000 +- 3,000 K based upon published spectral-line
analyses, and employing our new broad-band optical flux data along with the
known cluster distance, we find log L/L_sun = 3.78 +- 0.08 for the K648 central
star. Theoretical post-asymptotic-giant-branch evolutionary tracks imply a mass
of 0.60 +- 0.02 M_sun for this luminosity, which is significantly higher than
the mean mass of white dwarfs in globular clusters and the halo field (0.50 +-
0.02). The K648 central star exhibits no significant photometric variability in
our data; thus we find no direct evidence of a close binary companion. We
suggest that the progenitor of K648 experienced mass augmentation in a
close-binary merger, allowing it to evolve to a remnant of higher mass than
those of the single stars in the cluster.

</DOC>
<DOC>
<DOCNO> 83456 </DOCNO>
A Decomposition Theorem for Maximum Weight Bipartite Matchings


  Let G be a bipartite graph with positive integer weights on the edges and
without isolated nodes. Let n, N and W be the node count, the largest edge
weight and the total weight of G. Let k(x,y) be log(x)/log(x^2/y). We present a
new decomposition theorem for maximum weight bipartite matchings and use it to
design an O(sqrt(n)W/k(n,W/N))-time algorithm for computing a maximum weight
matching of G. This algorithm bridges a long-standing gap between the best
known time complexity of computing a maximum weight matching and that of
computing a maximum cardinality matching. Given G and a maximum weight matching
of G, we can further compute the weight of a maximum weight matching of G-{u}
for all nodes u in O(W) time.

</DOC>
<DOC>
<DOCNO> 170629 </DOCNO>
Fejer average and the short term behaviors of a wave packet in infinite


  The first two period behaviors of a quantum wave packet in an infinite square
well potential is studied. First, the short term behavior of expectation value
of a quantity on an equally weighted wave packet (EWWP) is in classical limit
proved to reproduce the Fej'{e}r average of the Fourier series decomposition of
the corresponding classical quantity. Second, in order to best mimic the
classical behavior, a nice relation between number $N$ of stationary states in
the EWWP with the average quantum number $n$ as $N\thickapprox \sqrt{n}$ is
revealed. Third, since the Fej\'{e}r average can only approximate the classical
quantity, it carries an uncertainty which in large quantum number case is
almost the same as the quantum uncertainty.

</DOC>
<DOC>
<DOCNO> 7692 </DOCNO>
A mixed mean-field/BCS phase with an energy gap at high $T_c$


  We construct a pair potential which in a scaling limit leads to a Hamiltonian
that generates co-existing mean-field and superconducting phases. Depending on
the relative values of the coupling constants, the superconducting phase may
exist at arbitrarily high temperatures.

</DOC>
<DOC>
<DOCNO> 101855 </DOCNO>
The modularity of the Barth-Nieto quintic and its relatives


  The moduli space of (1,3)-polarized abelian surfaces with full level-2
structure is birational to a double cover of the Barth-Nieto quintic. Barth and
Nieto have shown that these varieties have Calabi-Yau models Z and Y,
respectively. In this paper we apply the Weil conjectures to show that Y and Z
are rigid and we prove that the L-function of their common third \'etale
cohomology group is modular, as predicted by a conjecture of Fontaine and
Mazur. The corresponding modular form is the unique normalized cusp form of
weight 4 for the group \Gamma_1(6). By Tate's conjecture, this should imply
that Y, the fibred square of the universal elliptic curve S_1(6), and Verrill's
rigid Calabi-Yau Z_{A_3}, which all have the same L-function, are in
correspondence over Q. We show that this is indeed the case by giving explicit
maps.

</DOC>
<DOC>
<DOCNO> 102107 </DOCNO>
Local quivers and stable representations


  In this paper we introduce and study the local quiver as a tool to
investigate the etale local structure of moduli spaces of theta-stable
representations of quivers. As an application we determine the dimension
vectors associated to irreducible representations of torus knot groups.

</DOC>
<DOC>
<DOCNO> 121739 </DOCNO>
The Evolution of Population Gradients in Galaxy Clusters: the


  We present photometric and spectroscopic measurements of the galaxy
populations in clusters from the CNOC1 sample of rich, X-ray luminous clusters
at $0.18 < z < 0.55$. A classical measure of the galaxy blue fraction for
spectroscopically confirmed cluster members shows a significant Butcher-Oemler
effect for the sample, but only when radii larger than 0.5$r_{200}$ are
considered. We perform a principal component analysis of galaxy spectra to
divide the total cluster light into contributions from stellar populations of
different ages. Composite radial distributions of different stellar populations
show strong gradients as a function of cluster-centric radius. The composite
population is dominated by evolved populations in the core, and gradually
changes at radii greater than the virial radius to one which is similar to
coeval field galaxies. We do not see evidence at any radius within the clusters
for an excess of star formation over that seen in the coeval field. Within this
redshift range, significant evolution in the fractional population gradient is
seen. Both low and high redshift clusters have similar populations in the
cluster cores, but higher redshift clusters have steeper gradients and more
star forming galaxies at radii outside of the core region~-- in effect, a
restatement of the Butcher-Oemler effect. Luminosity density profiles are
consistent with a scenario where this phenomenon is due to a decline over time
in the infall rate of field galaxies into clusters. Depending on how long
galaxies reside in clusters before their star formation rates are diminished,
this suggests a decrease in the infall into clusters of a factor of $\sim 3$
between $z > 0.8$ and $z \sim 0.5$. We also discuss alternative scenarios for
the evolution of cluster populations.

</DOC>
<DOC>
<DOCNO> 68184 </DOCNO>
Non-accelerator neutrino mass searches


  The current status of non-accelerator based searches for effects of a
non-vanishing neutrino mass is reviewed. Beside the direct kinematical methods
this includes searches for magnetic moments and a discussion of the solar
neutrino problem. Double beta decay is not included.

</DOC>
<DOC>
<DOCNO> 69321 </DOCNO>
Super-Kamiokande 0.07 eV Neutrinos in Cosmology: Hot Dark Matter and the


  Relic neutrinos with mass in the range indicated by Super-Kamiokande results
if neutrino masses are hierarchial (about 0.07 eV) are many times deemed too
light to be cosmologically relevant. Here we remark that these neutrinos may
significantly contribute to the dark matter of the Universe (with a large
lepton asymmetry $L$) and that their existence might be revealed by the
spectrum of ultra high energy cosmic rays (maybe even in the absence of a large
$L$).

</DOC>
<DOC>
<DOCNO> 121081 </DOCNO>
The Age of the Inner Halo Globular Cluster NGC 6652


  HST (V,I) photometry has been obtained for the inner halo globular cluster
NGC 6652. The photometry reaches approximately 4 mag below the turn-off and
includes a well populated horizontal branch. This cluster is located close to
the Galactic center at a galactocentric distance of approximately 2.0 kpc with
a reddening of E(V-I) = 0.15 +/- 0.02 and has a metallicity of [Fe/H]
approximately -0.85. Based upon Delta(V) between the point on the sub-giant
branch which is 0.05 mag redder than the turn-off and the horizontal branch,
NGC 6652 is 11.7 +/- 1.6 Gyr old. Using this same Delta(V), precise
differential ages for 47 Tuc (a thick disk globular), M107 and NGC 1851 (both
halo clusters) were obtained. NGC 6652 appears to be the same age as 47 Tuc and
NGC 1851 (within +/- 1.2 Gyr), while there is a slight suggestion that M107 is
older than NGC 6652 by 2.3 +/- 1.5 Gyr. As this is a less than 2-sigma result,
this issue needs to be investigated further before a definitive statement
regarding the relative age of M107 and NGC 6652 may be made.

</DOC>
<DOC>
<DOCNO> 70722 </DOCNO>
Fixing the conformal window in QCD


  A physical characterization of Landau singularities is emphasized, which
should trace the lower boundary N_f^* of the conformal window in QCD and
supersymmetric QCD. A natural way to disentangle ``perturbative'' from
``non-perturbative'' contributions to amplitudes below N_f^* is suggested.
Assuming an infrared fixed point persists in the perturbative part of the QCD
coupling even below N_f^* leads to the condition \gamma(N_f^*)=1, where \gamma
is the critical exponent. Using the Banks-Zaks expansion, one gets 4<N_f^*<6.
This result is incompatible with the existence of an analogue of Seiberg
duality in QCD. The presence of a negative ultraviolet fixed point is required
both in QCD and in supersymmetric QCD to preserve causality within the
conformal window. Evidence for the existence of such a fixed point in QCD is
provided.

</DOC>
<DOC>
<DOCNO> 84560 </DOCNO>
The Innermost Stable Circular Orbit of Binary Black Holes


  We introduce a new method to construct solutions to the constraint equations
of general relativity describing binary black holes in quasicircular orbit.
Black hole pairs with arbitrary momenta can be constructed with a simple method
recently suggested by Brandt and Bruegmann, and quasicircular orbits can then
be found by locating a minimum in the binding energy along sequences of
constant horizon area. This approach produces binary black holes in a
"three-sheeted" manifold structure, as opposed to the "two-sheeted" structure
in the conformal-imaging approach adopted earlier by Cook. We focus on locating
the innermost stable circular orbit and compare with earlier calculations. Our
results confirm those of Cook and imply that the underlying manifold structure
has a very small effect on the location of the innermost stable circular orbit.

</DOC>
<DOC>
<DOCNO> 169564 </DOCNO>
Removed


 REMOVED by arXiv administration due to meta-abuse and duplicate submission

</DOC>
<DOC>
<DOCNO> 67957 </DOCNO>
Searching the Footprint of WIMPZILLAs


  We constrain mass, lifetime and contribution of a very slowly decaying Ultra
Heavy Dark Matter (UHDM) by simulating the cosmological evolution of its
remnants. Most of interactions which participate in energy dissipation are
included in the numerical solution of the Boltzmann equation. Cross-sections
are calculated either analytically or by using PYTHIA Monte Carlo program. This
paper describes in detail our simulation. To show the importance of the
distribution of matter in constraining WIMPZILLA characteristics, we consider
two extreme cases: a homogeneous universe, and a local halo with uniform
distribution. We show that in a homogeneous universe, the decay of UHDM with a
mass \sim 10^15 GeV and a lifetime \sim a few times \tau_0 the age of the
Universe, can not explain the flux of observed Ultra High Energy Cosmic Rays
(UHECRs). This shows the importance of nearby sources, notably galactic halo.
In a uniform clump with an over-density of \sim 200 extended to 100 kpc or
more, the lifetime must be \sim 10 - 100 \tau_0 or the contribution in the DM
must be proportionally smaller. We also compare our calculation with observed
gamma-rays at E \sim 10^11 eV by EGRET and CASA-MIA limit at E \sim 10^15 eV.
They are compatible with a UHDM with relatively short lifetime.

</DOC>
<DOC>
<DOCNO> 151990 </DOCNO>
Remarks on Liouville theory with boundary


  The bootstrap for Liouville theory with conformally invariant boundary
conditions will be discussed. After reviewing some results on one- and boundary
two-point functions we discuss some analogue of the Cardy condition linking
these data. This allows to determine the spectrum of the theory on the strip,
and illustrates in what respects the bootstrap for noncompact conformal field
theories with boundary is richer than in RCFT. We briefly indicate some
connections with $U_q(sl(2,R))$ that should help completing the bootstrap.

</DOC>
<DOC>
<DOCNO> 85146 </DOCNO>
Quantum Birth of a Hot Universe


  We consider quantum birth of a hot Universe in the framework of quantum
qeometrodynamics in the minisuperspace model. The energy spectrum of the
Universe in the pre-de-Sitter domain naturally explains the cosmic microwave
background (CMB) anisotropy. The false vacuum where the Universe tunnels from
the pre-de-Sitter domain is assumed to be of a Grand Unification Theory (GUT)
scale. The probability of the birth of a hot Universe from a quantum level
proves to be about $10^{-10^{14}}$. In the presence of matter with a negative
pressure (quintessence) it is possible for open and flat universes to be born
as well as closed ones.

</DOC>
<DOC>
<DOCNO> 12048 </DOCNO>
A multivariate multifractal model for return fluctuations


  In this paper we briefly review the recently inrtroduced Multifractal Random
Walk (MRW) that is able to reproduce most of recent empirical findings
concerning financial time-series : no correlation between price variations,
long-range volatility correlations and multifractal statistics. We then focus
on its extension to a multivariate context in order to model portfolio
behavior. Empirical estimations on real data suggest that this approach can be
pertinent to account for the nature of both linear and non-linear correlation
between stock returns at all time scales.

</DOC>
<DOC>
<DOCNO> 71861 </DOCNO>
Bootstrap quark model and spectra masses, electromagnetic properties of


  The paper is devoted to the construction of low-energy quark scattering
amplitudes. Bootstrap quark model allows to describe the light and heavy hadron
spectroscopy based on three principles: unitarity, analicity and crossing
symmetry. The resulting quark interaction appeared to be effectively
short-range. This interaction is determined mainly by the exchange in the gluon
channel: the constituent-gluon mass appeared to not be small. Our calculation
indicates an important role of an interaction which is induced by instantons.
Such an interaction is necessary for deriving both the pion mass and
$\eta$-$\eta'$ mass splitting. However, due to the rules of $1/N_c$-expansion
this interaction influences slightly the other channels while in the
$\eta$-$\eta'$ channel it provides the correct values of masses and gives the
angle of $\eta_1-\eta_8$ mixture close to that of the quark model. We discuss
the possibility of constructing the amplitudes which take into account the
quark confinement.

</DOC>
<DOC>
<DOCNO> 71290 </DOCNO>
On the Character of Leading Asymmetry in the Hadroproduction of Charmed


  The character of asymmetry between the spectra of Lambda_c and antiLambda_c
in the E781 experiment (FNAL) is discussed on the basis of the Quark Gluon
String Model(QGSM). As it was shown in the description of the asymmetry between
the spectra of leading and nonleading charmed mesons measured in Sigma^--A
interactions at p_L= 340 GeV/c in the WA89 experiment in previous studies, the
asymmetries between D^- and D^+ meson spectra and between D_s^- and D^+_s meson
spectra can be fitted by QGSM curves with the same parameter of string
fragmentation, a_1=10, as well as the asymmetry between the D-meson spectra in
pion-nuclear collisions in the E791 experiment. The forms of
Lambda_c/antiLambda_c asymmetry dependences measured in Sigma^-A and p-A
collisions at p_L= 600 GeV/c in the E781 experiment are different . It is shown
in the framework of QGSM that they depend on whether the diquarks of beam and
target particles took part in charmed baryon formation or not. The QGSM results
are compared with the calculations carried out by the other authors.

</DOC>
<DOC>
<DOCNO> 71432 </DOCNO>
Production of Charginos, Neutralinos, and Third Generation Sfermions at


  We discuss the production of charginos, neutralinos, and third generation
sfermions in $e^+e^-$ annihilation in the energy range $\sqrt{s} = 0.2-1$ TeV.
We present numerical predictions within the Minimal Supersymmetric Standard
Model for the cross sections and study the importance of beam polarization for
the determination of the underlying SUSY parameters.

</DOC>
<DOC>
<DOCNO> 67860 </DOCNO>
A Cosmological Mechanism for Stabilizing Moduli


  In this paper, we show how the generic coupling of moduli to the kinetic
energy of ordinary matter fields results in a cosmological mechanism that
influences the evolution and stability of moduli. As an example, we reconsider
the problem of stabilizing the dilaton in a non-perturbative potential induced
by gaugino condensates. A well-known difficulty is that the potential is so
steep that the dilaton field tends to overrun the correct minimum and to evolve
to an observationally unacceptable vacuum. We show that the dilaton coupling to
the thermal energy of matter fields produces a natural mechanism for gently
relaxing the dilaton field into the correct minimum of the potential without
fine-tuning of initial conditions. The same mechanism is potentially relevant
for stabilizing other moduli fields.

</DOC>
<DOC>
<DOCNO> 67641 </DOCNO>
CP Violation and Rare Decays


  After a brief essay on the current state of particle physics and possible
approaches to the opportunities before us, I summarize the contributions to the
Third Workshop on Physics and Detectors for DAFNE that deal with CP Violation
and Rare Decays.

</DOC>
<DOC>
<DOCNO> 80907 </DOCNO>
Confining Configurations in QCD and Relation to Rigid Strings


  The gauge field configurations of QCD gauge fields in the infrared regime are
obtained by magnetic symmetry condition. The effective dual action exhibits
dual Meissner effect with quarks included. A string representation of this
action corresponds to rigid string.

</DOC>
<DOC>
<DOCNO> 100500 </DOCNO>
From Special Lagrangian to Hermitian-Yang-Mills via Fourier-Mukai


  We exhibit a transformation taking special Lagrangian submanifolds of a
Calabi-Yau together with local systems to vector bundles over the mirror
manifold with connections obeying deformed Hermitian-Yang-Mills equations. That
is, the transformation relates supersymmetric A- and B-cycles. In this paper,
we assume that the mirror pair are dual torus fibrations with flat tori and
that the A-cycle is a section.
  We also show that this transformation preserves the (holomorphic)
Chern-Simons functional for all connections. Furthermore, on corresponding
moduli spaces of supersymmetric cycles it identifies the graded tangent spaces
and the holomorphic m-forms. In particular, we verify Vafa's mirror conjecture
with bundles in this special case.

</DOC>
<DOC>
<DOCNO> 11079 </DOCNO>
Polyhedral units and network connectivity in calcium aluminosilicate


  Structure factors for Cax/2AlxSi1-xO2 glasses (x=0,0.25,0.5,0.67) extended to
a wave vector of magnitude Q= 40 1/A have been obtained by high-energy x-ray
diffraction. For the first time, it is possible to resolve the contributions of
Si-O, Al-O and Ca-O coordination polyhedra to the experimental atomic pair
distribution functions (PDF). It has been found that both Si and Al are
four-fold coordinated and so participate in a continuous tetrahedral network at
low values of x. The number of network breaking defects in the form of
non-bridging oxygens (NBO's) increases slowly with x until x=0.5 (NBO's ~ 10%
at x=0.5). By x=0.67 the network breaking defects become significant as
evidenced by the significant drop in the average coordination number of Si. By
contrast, Al-O tetrahedra remain free of NBO's and fully integrated in the
Al/Si-O network for all values of x. Calcium maintains a rather uniform
coordination sphere of approximately 5 oxygen atoms for all values of x. The
results suggest that not only Si/Al-O tetrahedra but Ca-O polyhedra, too, play
a role in determining the glassy structure.

</DOC>
<DOC>
<DOCNO> 100799 </DOCNO>
Infinitesimally weak coupling, infinitely strong singularity of the


  In scattering by singular potentials $g^2U(s;r)$, the coupling constant $g^2$
is continuously decreased to zero while the stage $s$ of singularity raised
simultaneously beyond all limits by some functional relation $F(g^2;s)=0$. In
the extreme situation of this double limit, even the mere existence of a
nontrivial physical scattering problem is questionable. By iterating a pair of
integral equations, the relevant solution is developed here in terms of wave
functions into a pair of convergent series, each of which reduces in the double
limit $\{g^2\to 0;s\to\infty\}$ to a single term calculable by quadrature.

</DOC>
<DOC>
<DOCNO> 121357 </DOCNO>
UHECR Production and Curvature TeV Emission in Nearby, Dormant AGNs


  The possibility that rapidly rotating supermassive black holes associated
with quasar remnants may provide sites for the acceleration of ultra-high
energy cosmic rays (UHECRs) is considered. It is shown that prodigious TeV
emission through curvature losses is an important consequence of this
mechanism. Given the measured UHECR flux, it is expected that nearby dormant
AGNs will be detectable by current Tev experiments. The implications for the
Sgr A* source are also briefly considered.

</DOC>
<DOC>
<DOCNO> 151087 </DOCNO>
New N=2 Supersymmetric Vector-Tensor Interaction


  An N=2 supersymmetric self-interaction of the vector-tensor multiplet is
presented, in which the vector provides the gauge field for local central
charge transformations. The dual description in terms of a vector multiplet and
an N=1 superspace formulation are given.

</DOC>
<DOC>
<DOCNO> 8431 </DOCNO>
One-dimensional spin-1/2 Heisenberg antiferromagnet in a weak external


  The one dimensional spin-1/2 Heisenberg antiferromagnet in a weak magnetic
field h is studied using the bosonization method. We derive a set of
renormalization group equations. The fixed point is reached when the field is
scaled to the value at which the system is quarter-filled. As the magnetic
field varies, a continuum line of fixed points is formed. We compute the
uniform longitudinal susceptibility $\chi_z(h)$. The singular behavior of
$\chi_z(h)$ as $h\to 0$ is found to be contained in $1/\ln(h_o/h)$ with $h_o$ a
non-universal constant. The spin-spin correlations in the magnetic field are
calculated.

</DOC>
<DOC>
<DOCNO> 169829 </DOCNO>
Transverse Isotropy in Identical Particle Scattering


  It is pointed out that the cross section for the scattering of identical
charged bosons is isotropic over a broad angular range around 90 degrees when
the Sommerfeld parameter has a critical value, which depends exclusively on the
spin of the particle. A discussion of systems where this phenomenon can be
observed is presented.

</DOC>
<DOC>
<DOCNO> 85373 </DOCNO>
Space-time as strongly bent plate


  Futher development is made of a consept of space-time as multidimensional
elastic plate, proposed earlier in [20,21]. General equilibrium equations,
including 4-dimensional tangent stress tensor - energy-momentum tensor of
matter - are derived. Comparative analysis of multidimensional elasticity
theory (MET) and GR is given. Variational principle, boundary conditions,
energy-momentum tensor, matter and space-time signature are reviewed within the
context of MET.

</DOC>
<DOC>
<DOCNO> 8150 </DOCNO>
From naive to sophisticated behavior in multiagents based financial


  We discuss the behavior of two magnitudes, physical complexity and mutual
information function of the outcome of a model of heterogeneous, inductive
rational agents inspired in the El Farol Bar problem and the Minority Game. The
first is a measure rooted in Kolmogorov-Chaitin theory and the second one a
measure related with information entropy of Shannon.
  We make extensive computer simulations, as result of which, we propose an
ansatz for physical complexity and establish the dependence of exponent of that
ansatz from the parameters of the model. We discuss the accuracy of our results
and the relationship with the behavior of mutual information function as a
measure of time correlations of agents choice.

</DOC>
<DOC>
<DOCNO> 11992 </DOCNO>
Statistical mechanical derivation of the second law of thermodynamics


  In a macroscopic (quantum or classical) Hamiltonian system, we prove the
second law of thermodynamics in the forms of the minimum work principle and the
law of entropy increase, under the assumption that the initial state is
described by a general equilibrium distribution. Therefore the second law is a
logical necessity once we accept equilibrium statistical mechanics.

</DOC>
<DOC>
<DOCNO> 100188 </DOCNO>
An explicit formula for the determinant of the Abelian integral matrix


  We consider a polynomial h(x,y) in two complex variables of degree n+1>1 with
a generic higher homogeneous part. The rank of the first homology group of its
nonsingular level curve h(x,y)=t is n*n. To each 1- form in the variable space
and a generator of the homology group one associates the (Abelian) integral of
the form along the generator. The Abelian integral is a multivalued function in
t. For a fixed canonic tuple of n*n monomial 1- forms we consider the
multivalued square matrix function in t whose elements are the Abelian
integrals of the forms along the generators. Its determinant does not depend on
the choice of the generators in the homology group (up to change of sign, which
corresponds to change of generator system that reverses orientation).
  In 1999 Yu.S.Ilyashenko proved that the determinant of the Abelian integral
matrix is a polynomial in t of degree n*n whose zeroes are the critical values
of h. We give an explicit formula for the determinant.

</DOC>
<DOC>
<DOCNO> 121554 </DOCNO>
The Maximum Effect of Thermal Instability on Galactic Outflows


  We have investigated steady, radial gas outflows (or winds) from galaxies and
the development of thermal instability in the hot gas. In order to see the
maximum influence of the instability on the global structure of the galactic
outflows, we study inhomogeneous comoving flows and the non-linear fate of the
fluctuations in the flows. We compare the results with solutions for
homogeneous flows. In the case of supersonic flows, the global structure of
inhomogeneous flows is not much different from that of homogeneous flows.
However, detailed investigation shows that the average density of inhomogeneous
flows decreases faster than that of homogeneous flows, because local thermal
instability removes overdense regions in the inhomogeneous flows and reduces
the mass flux. We also find that when the gravity of a galaxy is strong, the
cold clouds formed from the removed gas are distributed in the galactic halo.
In the case of subsonic flows, the form of inhomogeneous flows is different
from that of homogeneous flows near the regions where the flows terminate. The
density rise appearing near the regions where the homogeneous flows terminate
is not seen in the inhomogeneous flows because the local thermal instability
decreases the mass flux. The cold clouds formed through thermal instability in
the inhomogeneous flow almost all coast to the same maximum radius.

</DOC>
<DOC>
<DOCNO> 8049 </DOCNO>
Pairing in Inhomogeneous Superconductors


  Starting from a t-J model, we introduce inhomogeneous terms to mimic stripes.
We find that if the inhomogeneous terms break the SU(2) spin symmetry the
binding between holes is tremendously enhanced in the thermodynamic limit. In
any other model (including homogeneous models) the binding in the thermodynamic
limit is small or neglible. By including these inhomogeneous terms we can
reproduce experimental neutron scattering data. We also discuss the connection
of the resulting inhomogeneity-induced superconductivity to recent experimental
evidence for a linear relation between magnetic incommensurability and the
superconducting transition temperature, as a function of doping.

</DOC>
<DOC>
<DOCNO> 71636 </DOCNO>
Non-invariant two-loop counterterms for the three-gauge-boson vertices


  Some practical applications of algebraic renormalization are discussed. In
particular we consider the two-loop QCD corrections to the three-gauge-boson
vertices involving photons, Z and W bosons. For this purpose also the
corresponding two-point functions have to be discussed. A recently developed
procedure is used to analyze the breaking terms of the functional identities
and explicit formulae for the universal counterterms are provided. Special
attention is devoted to the treatment of infra-red divergences.

</DOC>
<DOC>
<DOCNO> 12528 </DOCNO>
The Structure and a Bond-Valence-Sum Study of the 1-2-3 Superconductors


  We present a study of the crystal structure of the 1-2-3 superconductor
[Ca(x)La(1-x)][Ba$(1.75-x)La(0.25+x)]Cu(3)O(y) (``CLBLCO''). Because of the
presence of both La and Ba ions in the ``Ba'' layer, the local symmetry of
YBa(2)Cu(3)O(y) (``YBCO'') is lost. One can no longer assume that an ``apical''
oxygen atom always lies strictly on the line joining CuI and CuII ions, and a
Pauling bond-valence calculation is very useful as an adjunct to the Rietveld
refinement of the positions of the La and Ba ions. When a Rietveld analysis is
performed allowing for the possibility that the apical oxygen atoms may be
slightly displaced along the a or b direction, the bond valence sums for both
La and Ba are close to the natural oxidation states of these ions.
  We have also used the bond-valence-sum method to study the mean oxidation
states of the CuI and CuII ions in both CLBLCO and YBCO. Our results for YBCO
differ from some previously published results. Our main conclusion is that,
while the method may be useful in finding the charge concentration on the CuII
plane, it definitely does not yield the concentration of mobile holes, nor the
concentration of superconducting charge carriers.

</DOC>
<DOC>
<DOCNO> 122987 </DOCNO>
Supercomputer Simulations of Disk Galaxies


  The time evolution of models for an isolated disk of highly flattened
galaxies of stars is investigated by direct integration of the Newtonian
equations of motion of N=30,000 identical stars over a time span of many
galactic rotations. Certain astronomical implications of the simulations to
actual disk-shaped (i.e. rapidly rotating) galaxies are explored as well.

</DOC>
<DOC>
<DOCNO> 72316 </DOCNO>
Origin of a classical space in guantum cosmologies


  The influence of vector fields on the origin of a classical space in quantum
cosmologies and on the possible compactification process in multidimensional
gravity is investigated. It is shown that all general features of the
transition between classical and quantum regimes of the evolution can be
obtained within the simplest Bianchi-I model for arbitrary number of
dimensions. It is shown that the classical space appears when the horizon size
reaches the smallest of characteristic scales (the characteristic scale of
inhomogeneity or a scale associated with vector fields). In multidimensional
case the presence of vector fields completely removes the initial stage of the
compactification process which takes place in the case of vacuum models.

</DOC>
<DOC>
<DOCNO> 70436 </DOCNO>
Coarse graining and renormalization


  Formulating the QFT's as coarse grained 'low' energy sectors of a postulated
complete quantum theory of everything with the 'high' energy modes integrated
out or 'clustering' into 'low' energy objects, we can evaluate the Feynman
amplitudes by solving a series of natural differential equations which
automatically dissolves the necessity of infinity subtraction and the
associated subtleties. This new strategy has direct implications to the scheme
dependence problem.

</DOC>
<DOC>
<DOCNO> 117967 </DOCNO>
ISO far-infrared observations of rich galaxy clusters II. Sersic 159-03


  The far-infrared emission from rich galaxy clusters is investigated. Maps
have been obtained by ISO at 60, 100, 135, and 200 microns using the PHT-C
camera. Ground based imaging and spectroscopy were also acquired. Here we
present the results for the cooling flow cluster Sersic 159-03. An infrared
source coincident with the dominant cD galaxy is found. Some off-center sources
are also present, but without any obvious counterparts.

</DOC>
<DOC>
<DOCNO> 67726 </DOCNO>
The Solar Neutrino Problem in the Light of a Violation of the


  We have found that long-wavelength neutrino oscillations induced by a tiny
breakdown of the weak equivalence principle of general relativity can provide a
viable solution to the solar neutrino problem.

</DOC>
<DOC>
<DOCNO> 13991 </DOCNO>
Significance of the direct relaxation process in the low-energy spin


  In response to recent nuclear-magnetic-resonance measurements on a
ferrimagnetic chain compound NiCu(C_7H_6N_2O_6)(H_2O)_3 2H_2O [Solid State
Commun. {\bf 113} (2000) 433], we calculate the nuclear spin-lattice relaxation
rate 1/T_1 in terms of a modified spin-wave theory. Emphasizing that the
dominant relaxation mechanism arises from the direct (single-magnon) process
rather than the Raman (two-magnon) one, we explain the observed temperature and
applied-field dependences of 1/T_1. Ferrimagnetic relaxation phenomena are
generally discussed and novel ferrimagnets with extremely slow dynamics are
predicted.

</DOC>
<DOC>
<DOCNO> 117017 </DOCNO>
The birth of special relativity. "One more essay on the subject"


  Special relativity was discovered at the eve of the century, but finds its
roots in the 19th century efforts to understand the optics and electromagnetism
of moving bodies. These roots are reviewed in Parts 1 and 2, the latter being
specially devoted to the works of Lorentz and of Poincare up to 1904. Part 3
contains a detailed comparison of the works of Einstein and of Poincare in
1905. It is shown that both authors succeeded in constructing a coherent and
fully relativistic theory, although their ideas about the ether were radically
different. In Part 4, the question of the respective merits of the three
potential fathers of special relativity (i.e. Lorentz, Poincare, Einstein) is
discussed again, at the light of the preceding analysis and of the "post-1905"
developments of the theory.

</DOC>
<DOC>
<DOCNO> 152155 </DOCNO>
D-branes on Calabi-Yau manifolds and helices


  We investigate further on the correspondence between branes on a Calabi-Yau
in the large volume limit and in the orbifold limit. We conjecture a new
procedure which improves computationally the McKay correspondence and prove it
in a non trivial example. We point out the relevance of helices and try to draw
some general conclusions about Beilinson theorem and McKay correspondence.

</DOC>
<DOC>
<DOCNO> 99733 </DOCNO>
Generic coverings of plane with A-D-E-singularities


  We generalize results of the paper math.AG/9803144, in which Chisini's
conjecture on the unique reconstruction of f by the curve B is investigated.
For this fibre products of generic coverings are studied. The main inequality
bounding the degree of a covering in the case of existence of two nonequivalent
coverings with the branch curve B is obtained. This inequality is used for the
proof of the Chisini conjecture for m-canonical coverings of surfaces of
general type for $m\ge 5$.

</DOC>
<DOC>
<DOCNO> 13026 </DOCNO>
Manyparticle interactions and local structure of the metallic hydrogen


  On the basis of the perturbation expansion for electron gas energy in the
third order to the electron-ion potential the pair and irreducible three-ion
interaction potentials in metallic hydrogen are calculated. The irreducible
potential of three-ion interaction has attractive nature at short interionic
separation and oscillates at large ones. The anisotropic character of the
three-ion interaction is shown. The potential relief of the pair ions relative
to the third ion is constructed. This relief has some potential wells and
valleys which connect them. The important role of the irreducible three-ion
interaction in formation of the local order in three- and four-ion clusters is
shown. The potential relief of an equiangular ion triplet relative to the
fourth ion is calculated. This relief has deep potential well for fourth ion at
interionic separation corresponding interproton separation in molecule $H_{2}$.
The quasiclassical probability of ion transition into this well is evaluated.
The life time of metallic phase of hydrogen relative to the tunneling
nucleation of the $H_{2}$ molecules is estimated.

</DOC>
<DOC>
<DOCNO> 120227 </DOCNO>
Recent results by the MOA group on gravitational microlensing


  Recent work by the MOA gravitational microlensing group is briefly described,
including (i) the current observing strategy, (ii) use of a high-speed parallel
computer for analysis of results by inverse ray shooting, (iii) analysis of the
light curve of event OGLE-2000-BUL12 in terms of extra-solar planets, and (iv)
the MOA alert system using difference imaging.

</DOC>
<DOC>
<DOCNO> 83145 </DOCNO>
Local Diagnosis


  In an earlier work, we have presented operations of belief change which only
affect the relevant part of a belief base. In this paper, we propose the
application of the same strategy to the problem of model-based diangosis. We
first isolate the subset of the system description which is relevant for a
given observation and then solve the diagnosis problem for this subset.

</DOC>
<DOC>
<DOCNO> 122731 </DOCNO>
Star Formation from Turbulent Fragmentation


  Star formation is intimately linked to the dynamical evolution of molecular
clouds. Turbulent fragmentation determines where and when protostellar cores
form, and how they contract and grow in mass via accretion from the surrounding
cloud material. Efficiency, spatial distribution and timescale of star
formation in turbulent clouds are estimated by comparing numerical models of
self-gravitating isothermal gas where turbulence is assumed to have decayed or
is driven at supersonic speed on various wavelengths. Turbulence that is not
continuously replenished or that is driven on large scales leads to a rapid
formation of stars in a clustered mode, whereas interstellar turbulence that
carries most energy on small scales results in isolated star formation with low
efficiency. Protostellar accretion rates strongly vary in time and peak at a
few 10^-5 M_sun/year. The clump mass spectrum for models of pure hydrodynamic
turbulence is steeper than the observed one, but becomes comparable when
including gravity. The mass spectrum of dense cores, on the other hand, is
log-normal for decaying and large-wavelength turbulence, similar to the IMF,
but is to flat in the case of small-scale turbulence.

</DOC>
<DOC>
<DOCNO> 80933 </DOCNO>
Lattice QCD at finite temperature


  Recent developments in finite-temperature QCD with dynamical quarks are
reviewed focusing on the topics of critical temperature, the equation of state,
and critical behaviors around the chiral phase transition.

</DOC>
<DOC>
<DOCNO> 13373 </DOCNO>
c-Axis Phase Coherence and Spin Fluctuations in Cuprates


  There is a consensus that superconductivity (SC) in cuprates is
two-dimensional. It is widely believed that the long-range phase coherence
appears at T_{c} due to the Josephson coupling between SC CuO_{2} (bi-, tri-,
>...)layers. Recent T_{c} and resistivity measurements in Tl2212 as a function
of applied pressure (Salvetat J.-P. et al., Europhys. Lett., 52 (2000) 584)
show that the interlayer Josephson-coupling mechanism does not fit the data.
Here we analyze data obtained in Andreev reflection, neutron scattering,
microwave, muon spin relaxation, tunneling and resistivity measurements
performed on different cuprates, mainly, on YBCO, Bi2212 and LSCO. The analysis
of the data shows that the long-range phase coherence in the cuprates
intimately relates to antiferromagnetic interactions along the c axis. At the
same time, it seems that the in-plane mechanism of the SC has no or little
relations to the magnetic interactions along the c axis.

</DOC>
<DOC>
<DOCNO> 120035 </DOCNO>
A High Intrinsic Peculiarity Rate Among Type Ia Supernovae


  We have compiled a sample of 45 Type Ia supernovae (SNe Ia) discovered by the
Lick Observatory Supernova Search (LOSS) and the Beijing Astronomical
Observatory Supernova Survey (BAOSS), and determined the rate of
spectroscopically peculiar SNe Ia (i.e., SN 1986G-like, SN 1991bg-like, and SN
1991T-like objects) and the luminosity function of SNe Ia. Because of the
nature of the two surveys (distance-limited with small baselines and deep
limiting magnitudes), nearly all SNe Ia have been discovered in the sample
galaxies of LOSS and BAOSS; thus, the observed peculiarity rate and luminosity
function of SNe Ia are intrinsic. We find that 36$\pm$9% of nearby SNe Ia are
peculiar; specifically, the luminosity function of SNe Ia consists of 20% SN
1991T-like, 64% normal, and 16% SN 1991bg-like objects. We have compared our
results to those found by earlier studies, and to those found at high redshift.
The apparent dearth of SN 1991T-like objects at high redshift may be due to
extinction, and especially to the difficulty of recognizing them from spectra
obtained past maximum brightness or from spectra with low signal-to-noise
ratios. Implications of the high peculiarity rate for the progenitor systems of
SNe Ia are also briefly discussed.

</DOC>
<DOC>
<DOCNO> 121004 </DOCNO>
EUV/X-ray Emission and the Thermal and Ionization Structure of B Star


  We discuss the EUV and X-ray properties of B stars, focusing on $\epsilon$
CMa (B2 II) which is the only star with both emission lines and a photospheric
continuum detected with EUVE. We explore the modest effects of the photospheric
EUV continua on the wind, as well as the much stronger effects of the
short-wavelength EUV and soft X-ray emission lines. Attenuation of the EUV and
soft X-ray emission by the wind plays an important role, and leads to the
reprocessing of X-rays via He$^+$ ionization and the Bowen mechanism in the
wind. Finally, we explore some of the new diagnostics that will shortly become
available with the next generation of high spectral resolution X-ray
telescopes. All of this analysis is presented in the context of a two component
stellar wind--a dense component (clumps) that contains most of the mass but
fills a negligible fraction of the volume, and a rarefied component that fills
most of the volume but accounts for only a small fraction of the mass.

</DOC>
<DOC>
<DOCNO> 40579 </DOCNO>
Differential cross section measurement of eta photoproduction on the


  The differential cross section for the reaction p(gamma, eta p) has been
measured from threshold to 1100 MeV photon laboratory energy. For the first
time, the region of the S11(1535) resonance is fully covered in a
photoproduction experiment and allows a precise extraction of its parameters at
the photon point. Above 1000 MeV, S-wave dominance vanishes while a P-wave
contribution is observed whose nature will have to be clarified. These high
precision data together with the already measured beam asymmetry data will
provide stringent constraints on the extraction of new couplings of baryon
resonances to the eta meson.

</DOC>
<DOC>
<DOCNO> 13724 </DOCNO>
A macroscopically frustrated Ising model


  A disordered spin glass model where both static and dynamical properties
depend on macroscopic magnetizations is presented. These magnetizations
interact via random couplings and, therefore, the typical quenched realization
of the system exhibit a macroscopic frustration. The model is solved by using a
revisited replica approach, and the broken symmetry solution turns out to
coincide with the symmetric solution. Some dynamical aspects of the model are
also discussed, showing how it could be a useful tool for describing some
properties of real systems as, for example, natural ecosystems or human social
systems.

</DOC>
<DOC>
<DOCNO> 67689 </DOCNO>
A D-Brane Alternative to the MSSM


  The success of SU(5)-like gauge coupling unification boundary conditions
$g_3^2=g_2^2=5/3 g_1^2$ has biased most attempts to embed the SM interactions
into a unified structure. After discussing the limitations of the orthodox
approach, we propose an alternative that appears to be quite naturally implied
by recent developments based on D-brane physics. In this new alternative: 1)
The gauge group, above a scale of order 1 TeV, is the minimal left-right
symmetric extension $SU(3)\times SU(2)_L\times SU(2)_R\times U(1)_{B-L}$ of the
SM; 2) Quarks, leptons and Higgs fields come in three generations; 3) Couplings
unify at an intermediate string scale $M_s= 9\times 10^{11}$ GeV with boundary
conditions $g_3^2=g_L^2=g_R^2=32/3 g_{B-L}^2$. This corresponds to the natural
embedding of gauge interactions into D-branes and is different from the
standard SO(10) embedding which corresponds to $k_{B-L}=8/3$. Unification only
works in the case of three generations;
  4) Proton stability is automatic due to the presence of $Z_2$ discrete
R-parity and lepton parities. A specific Type IIB string orientifold model with
the above characteristics is constructed. The existence of three generations is
directly related to the existence of three complex extra dimensions.
  In this model the string scale can be identified with the intermediate scale
and SUSY is broken also at that scale due to the presence of anti-branes in the
vacuum.
  We discuss a number of phenomenological issues in this model including Yukawa
couplings and a built-in axion solution to the strong-CP problem. The present
framework could be tested by future accelerators by finding the left-right
symmetric extension of the SM at a scale of order 1 TeV.

</DOC>
<DOC>
<DOCNO> 122448 </DOCNO>
Lower Limits on Lorentz Factors in Gamma Ray Bursts


  As is well-known, the requirement that gamma ray bursts (GRB's) be optically
thin to high energy photons yields a lower limit on the Lorentz factor (\gamma)
of the expansion. In this paper, we provide a simple derivation of the lower
limit on \gamma due to the annihilation of photon pairs, and correct the errors
in some of the previous calculations of this limit. We also derive a second
limit on \gamma due to scattering of photons by pair-created electrons and
positrons. For some bursts, this limit is the more stringent. In addition, we
show that a third limit on \gamma, which is obtained by considering the
scattering of photons by electrons which accompany baryons, is nearly always
less important than the second limit. Finally, we evaluate these limits for a
number of bursts.

</DOC>
<DOC>
<DOCNO> 8701 </DOCNO>
Two-subband electron transport in nonideal quantum wells


  Electron transport in nonideal quantum wells (QW) with large-scale variations
of energy levels is studied when two subbands are occupied. Although the mean
fluctuations of these two levels are screened by the in-plane redistribution of
electrons, the energies of both levels remain nonuniform over the plane. The
effect of random inhomogeneities on the classical transport is studied within
the framework of a local response approach for weak disorder. Both short-range
and small-angle scattering mechanisms are considered. Magnetotransport
characteristics and the modulation of the effective conductivity by transverse
voltage are evaluated for different kinds of confinement potentials (hard wall
QW, parabolic QW, and stepped QW).

</DOC>
<DOC>
<DOCNO> 151585 </DOCNO>
Dynamics of Strings in Noncommutative Gauge Theory


  We continue our study of solitons in noncommutative gauge theories and
present an extremely simple BPS solution of N=4 U(1) noncommutative gauge
theory in 4 dimensions, which describes N infinite D1 strings that pierce a D3
brane at various points, in the presence of a background B-field in the
Seiberg-Witten limit. We call this solution the N-fluxon. For N=1 we calculate
the complete spectrum of small fluctuations about the fluxon and find three
kinds of modes: the fluctuations of the superstring in 10 dimensions arising
from fundamental strings attached to the D1strings, the ordinary particles of
the gauge theory in 4 dimensions and a set of states with discrete spectrum,
localized at the intersection point--- corresponding to fundamental strings
stretched between the D1string and the D3 brane. We discuss the fluctuations
about theN-fluxon as well and derive explicit expressions for the amplitudes of
interactions between these various modes. We show that translations in
noncommutative gauge theories are equivalent to gauge transformations (plus a
constant shift of the gauge field) and discuss the implications for the
translational zeromodes of our solitons. We also find the dyonic versions of
N-fluxon, as well as of our previous string-monopole solution.

</DOC>
<DOC>
<DOCNO> 152571 </DOCNO>
Branes on Group Manifolds, Gluon Condensates, and twisted K-theory


  In this work we study the dynamics of branes on group manifolds G deep in the
stringy regime. After giving a brief overview of the various branes that can be
constructed within the boundary conformal field theory approach, we analyze in
detail the condensation processes that occur on stacks of such branes. At large
volume our discussion is based on certain effective gauge theories on
non-commutative `fuzzy' spaces. Using the `absorption of the boundary
spin'-principle which was formulated by Affleck and Ludwig in their work on the
Kondo model, we extrapolate the brane dynamics into the stringy regime. For
supersymmetric theories, the resulting condensation processes turn out to be
consistent with the existence of certain conserved charges taking values in
some non-trivial discrete abelian groups. We obtain strong constraints on these
charge groups for G = SU(N). The results may be compared with a recent proposal
of Bouwknegt and Mathai according to which charge groups on curved spaces X
(with a non-vanishing NSNS 3-form field strength H) are given by the twisted
K-groups K*_H(X).

</DOC>
<DOC>
<DOCNO> 13141 </DOCNO>
An Exact Solution for the Lattice Gas Model in One Dimension


  A simple method to obtain a canonical partition function for one dimensional
lattice gas model is presented. The simplification is based upon rewriting a
sum over all possible configurations to a sum over numbers of clusters in the
system.

</DOC>
<DOC>
<DOCNO> 151487 </DOCNO>
Extended Self-Dual Configurations as Stable Exact Solutions in


  A class of exact solutions to the Born-Infeld field equations, over manifolds
of any even dimension, is constructed. They are an extension of the self-dual
configurations. They are local minima of the action for riemannian base
manifolds and local minima of the Hamiltonian for pseudo-riemannian ones. A
general explicit expression for the Born-Infeld determinant is obtained, for
any dimension of space-time.

</DOC>
<DOC>
<DOCNO> 67937 </DOCNO>
A Small Cosmological Constant from a Large Extra Dimension


  We propose a new approach to the Cosmological Constant Problem which makes
essential use of an extra dimension. A model is presented in which the Standard
Model vacuum energy ``warps'' the higher-dimensional spacetime while preserving
4D flatness. We argue that the strong curvature region of our solutions may
effectively cut off the size of the extra dimension, thereby giving rise to
macroscopic 4D gravity without a cosmological constant. In our model, the
higher-dimensional gravity dynamics is treated classically with carefully
chosen couplings. Our treatment of the Standard Model is however fully quantum
field-theoretic, and the 4D flatness of our solutions is robust against
Standard Model quantum loops and changes to Standard Model couplings.

</DOC>
<DOC>
<DOCNO> 100159 </DOCNO>
Ramsey-Milman phenomenon, Urysohn metric spaces, and extremely amenable


  In this paper we further study links between concentration of measure in
topological transformation groups, existence of fixed points, and Ramsey-type
theorems for metric spaces. We prove that whenever the group $\Iso(\U)$ of
isometries of Urysohn's universal complete separable metric space $\mathbb U$,
equipped with the compact-open topology, acts upon an arbitrary compact space,
it has a fixed point. The same is true if $\U$ is replaced with any generalized
Urysohn metric space $U$ that is sufficiently homogeneous. Modulo a recent
theorem by Uspenskij that every topological group embeds into a topological
group of the form $\Iso(U)$, our result implies that every topological group
embeds into an extremely amenable group (one admitting an invariant
multiplicative mean on bounded right uniformly continuous functions). By way of
the proof, we show that every topological group is approximated by finite
groups in a certain weak sense. Our technique also results in a new proof of
the extreme amenability (fixed point on compacta property) for infinite
orthogonal groups. Going in the opposite direction, we deduce some Ramsey-type
theorems for metric subspaces of Hilbert spaces and for spherical metric spaces
from existing results on extreme amenability of infinite unitary groups and
groups of isometries of Hilbert spaces.

</DOC>
<DOC>
<DOCNO> 150347 </DOCNO>
The operator form of the effective potential governing the time


  This paper presents the operator form of the effective potential V governing
the time evolution in 2 and 3 and n dimensional subspace of states. The general
formula for the n dimensional case is considered the starting point for the
calculation of the explicit formulae for 2 and 3 dimensional degenerate and
non-degenerate cases. We relate the 2 and 3 dimensional cases to some physical
systems which are currently investigated.

</DOC>
<DOC>
<DOCNO> 40307 </DOCNO>
Mini-Review on Extra Dimensions


  One of the most stimulating recent ideas in particle physics involves a
possibility that our universe has additional compactified spatial dimensions,
perhaps as large as 1 mm. In this mini-review, we discuss the results of recent
experimental searches for such large extra dimensions.

</DOC>
<DOC>
<DOCNO> 8473 </DOCNO>
Hamiltonian dynamics and geometry of phase transitions in classical XY


  The Hamiltonian dynamics associated to classical, planar, Heisenberg XY
models is investigated for two- and three-dimensional lattices. Besides the
conventional signatures of phase transitions, here obtained through time
averages of thermodynamical observables in place of ensemble averages,
qualitatively new information is derived from the temperature dependence of
Lyapunov exponents. A Riemannian geometrization of newtonian dynamics suggests
to consider other observables of geometric meaning tightly related with the
largest Lyapunov exponent. The numerical computation of these observables -
unusual in the study of phase transitions - sheds a new light on the
microscopic dynamical counterpart of thermodynamics also pointing to the
existence of some major change in the geometry of the mechanical manifolds at
the thermodynamical transition. Through the microcanonical definition of the
entropy, a relationship between thermodynamics and the extrinsic geometry of
the constant energy surfaces $\Sigma_E$ of phase space can be naturally
established. In this framework, an approximate formula is worked out,
determining a highly non-trivial relationship between temperature and topology
of the $\Sigma_E$. Whence it can be understood that the appearance of a phase
transition must be tightly related to a suitable major topology change of the
$\Sigma_E$. This contributes to the understanding of the origin of phase
transitions in the microcanonical ensemble.

</DOC>
<DOC>
<DOCNO> 118127 </DOCNO>
Cosmic Ray Rejection by Linear Filtering of Single Images


  We present a convolution-based algorithm for finding cosmic rays in single
well-sampled astronomical images. The spatial filter used is the point spread
function (approximated by a Gaussian) minus a scaled delta function, and cosmic
rays are identified by thresholding the filtered image. This filter searches
for features with significant power at spatial frequencies too high for
legitimate objects. Noise properties of the filtered image are readily
calculated, which allows us to compute the probability of rejecting a pixel not
contaminated by a cosmic ray (the false alarm probability). We demonstrate that
the false alarm probability for a pixel containing object flux will never
exceed the corresponding probability for a blank sky pixel, provided we choose
the convolution kernel appropriately. This allows confident rejection of cosmic
rays superposed on real objects. Identification of multiple-pixel cosmic ray
hits can be enhanced by running the algorithm iteratively, replacing flagged
pixels with the background level at each iteration.

</DOC>
<DOC>
<DOCNO> 12175 </DOCNO>
Some Aspects regarding Renormalisation Theory of Critical Phenomena


  Concerning renormalisation group theory applied to phase transitions, we
examine the value of positive numerical and analytical evidence, the divergent
short-wavelength behaviour of classical free fields and the absence of
UV-divergences in quantum field theories with proper mathematical handling. We
conclude as to the inadequacy of the conceptual and mathematical framework of
renormalisation theory of critical phenomena.

</DOC>
<DOC>
<DOCNO> 68382 </DOCNO>
Renormalization Scheme and Higher Loop Stability in Hadronic $\tau$


  We apply an analytic description to the inclusive decay of the $\tau$ lepton.
We argue that this method gives not only a self-consistent description of the
process both in the timelike region by using the initial expression for
$R_\tau$ and in the spacelike domain by using the analytic properties of the
hadronic correlator, but also leads to the fact that theoretical uncertainties
associated with unknown higher-loop contributions and renormalization scheme
dependence can be reduced dramatically.

</DOC>
<DOC>
<DOCNO> 10566 </DOCNO>
Mean-field theory of learning: from dynamics to statics


  Using the cavity method and diagrammatic methods, we model the dynamics of
batch learning of restricted sets of examples. Simulations of the Green's
function and the cavity activation distributions support the theory well. The
learning dynamics approaches a steady state in agreement with the static
version of the cavity method. The picture of the rough energy landscape is
reviewed.

</DOC>
<DOC>
<DOCNO> 169869 </DOCNO>
Reversible combination of inequivalent kinds of multipartite


  We present a family of tri-partite entangled states that, in an asymptotical
sense, can be reversibly converted into EPR states shared by only two of
parties (say B and C), and tripartite GHZ states. Thus we show that bipartite
and genuine tripartite entanglement can be reversibly combined in several
copies of a single tripartite state. For such states the corresponding
fractions of GHZ and of EPR states represent a complete quantification of their
(asymptotical) entanglement resources. More generally, we show that the three
different kinds of bipartite entanglement (AB, AC and BC EPR states) and
tripartite GHZ entanglement can be reversibly combined in a single state of
three parties. Finally, we generalize this result to any number of parties.

</DOC>
<DOC>
<DOCNO> 69330 </DOCNO>
Primordial Black Holes from Non-Equilibrium Second Order Phase


  The collapse of sufficiently large closed domain wall produced during second
order phase transition in the vacuum state of a scalar field can lead to the
formation of black hole. The origin of domain walls with appropriate size and
energy density could be a result of evolution of an effectively massless scalar
field at the inflational epoch. We demonstrate that in this case the situation
is valued when there are compact domains of less favorable vacuum surrounded by
a sea of another vacuum. Each domain has a surface composed of vacuum wall that
stores a significant amount of energy, and can collapse into the black hole.
This offers the way of massive primordial black holes formation in the early
Universe.

</DOC>
<DOC>
<DOCNO> 11822 </DOCNO>
Disordering Transitions in Vortex Matter: Peak Effect and Phase Diagram


  Using numerical simulations of magnetically interacting vortices in
disordered layered superconductors we obtain the static vortex phase diagram as
a function of magnetic field and temperature. For increasing field or
temperature, we find a transition from ordered straight vortices to disordered
decoupled vortices. This transition is associated with a peak effect in the
critical current. For samples with increasing disorder strength the field at
which the decoupling occurs decreases. Long range, nonlinear interactions in
the c-axis are required to observe the effect.

</DOC>
<DOC>
<DOCNO> 10922 </DOCNO>
Effect of \gamma-irradiation on superconductivity in polycrystalline


  A bulk polycrystalline sample of YBa_{2}Cu_{3}O_{7-\delta} (\delta \approx
0.1) has been irradiated by \gamma-rays with ^{60}Co source. Non-monotonic
behavior of T_c (defined as the temperature at which normal resistance is
halved) with increasing irradiation dose \Phi (up to about 220 MR) is observed:
T_c decreases at low doses (\Phi \leq 50 MR) from initial value (\approx 93 K)
by about 2 K and then rises, forming minimum. At highest doses (\Phi \geq 120
MR) T_c goes down again. The temperature width, \delta T_c, of resistive
transition increases rather sharp with dose below 75 MR and somewhat drops at
higher dose. We believe that this effect is revealed for the first time at
\gamma-irradiation of high-T_c superconductor. The cross section for the
displacement of lattice atoms in YBCO by \gamma-rays due to the Compton process
were calculated, and possible dpa values were estimated. The results obtained
are discussed taking into account that the sample is granular superconductor
and, hence, the observed variations of superconducting properties should be
connected primarily with the influence of \gamma-rays on intergrain Josephson
coupling.

</DOC>
<DOC>
<DOCNO> 170616 </DOCNO>
Entanglement and Extreme Spin Squeezing


  For any mean value of a cartesian component of a spin vector we identify the
smallest possible uncertainty in any of the orthogonal components. The
corresponding states are optimal for spectroscopy and atomic clocks. We show
that the results for different spin J can be used to identify entanglement and
to quantity the depth of entanglement in systems with many particles. With the
procedure developed in this letter, collective spin measurements on an ensemble
of particles can be used as an experimental proof of multi-particle
entanglement

</DOC>
<DOC>
<DOCNO> 101250 </DOCNO>
Addition Formulae for Non-Abelian Theta Functions


  This paper aims at generalizing various formulae valid for theta functions of
Jacobian varieties for theta functions of moduli spaces of vector bundles of
rank $r> 1$, i.e. non-abelian theta functions. The addition formula and the
variations of the values of theta functions under cyclic coverings are given.

</DOC>
<DOC>
<DOCNO> 13743 </DOCNO>
Existence of the upper critical dimension of the Kardar-Parisi-Zhang


  The controversy whether or not he Kardar-Parisi-Zhang (KPZ) equation has an
upper critical dimension (UCD) is going on for quite a long time. Some
approximate integral equations for the two-point function served as an
indication for the existence of a UCD, by obtaining a dimension, above which
the equation does not have a strong coupling solution. A surprising aspect of
these studies, however, is that variuos authors that considered the same
equation produced large variations in the UCD. This caused some doubts
concerning the existence of a UCD. Here we revisit these calculations, describe
the reason for such large variations in the results of identical calculations,
show by a large-d expansion that indeed there exist a UCD and then obtain it
numerically by properly defining the integrals involved.

</DOC>
<DOC>
<DOCNO> 69235 </DOCNO>
New exact solutions for inflationary cosmological perturbations


  From a general ansatz for the effective potential of cosmological
perturbations we find new, exact solutions in single-scalar-field inflation: a
three parameter family of exact inflationary solutions that encompasses all
exact solutions that have been known previously (power-law inflation, Easther's
model, and a generalised version of Starobinsky's solution). The main feature
of this new family is that the spectral indices are scale dependent.

</DOC>
<DOC>
<DOCNO> 119996 </DOCNO>
Testing Dispersion Relations of Quantum $\kappa$-Poincar\'e Algebra on


  Following the procedure proposed recently by Martin and Brandenberger we
investigate the spectrum of the cosmological perturbations in the case when the
``trans-Plackian'' dispersion relations are motivated by the quantum
$\kappa$-Poincar\'e algebra. We find that depending on the choice of initial
conditions of the perturbations, the spectrum either differs from the flat one
for for instantaneous Minkowski vacuum or, in the case of initial conditions
minimizing energy density, leads to the observed scale-invariant
Harrison-Zel'dovich spectrum in the Friedmann epoch.

</DOC>
<DOC>
<DOCNO> 84198 </DOCNO>
Is the cosmological singularity really unavoidable in general


  The initial singularity problem in standard general relativity is treated on
the light of a viewpoint asserting that this formulation of Einstein's theory
and its conformal formulations are physically equivalent. We show that flat
Friedmann-Robertson-Walker universes and open dust-filled and radiation-filled
universes are singularity free when described in terms of the formulation of
general relativity conformal to the canonical one.

</DOC>
<DOC>
<DOCNO> 67858 </DOCNO>
TeV Gravitons and Kaluza-Klein Excitations in $e^+e^-$ and $e^-e^-$


  We review the capability of $e^+e^-$ and $e^-e^-$ colliders to detect the
virtual exchange of Kaluza-Klein towers of gravitons within the large extra
dimension scenario of Arkani-Hamed, Dimopoulos and Dvali and in the localized
gravity model of Randall and Sundrum with non-factorizable geometry.

</DOC>
<DOC>
<DOCNO> 120959 </DOCNO>
A New Look at Simple Inhomogeneous Chemical Evolution


  A rudimentary, one-zone, closed-box model for inhomogeneous chemical
evolution is offered as an alternative reference than the Simple model in the
limit of no mixing. The metallicity distribution functions (MDFs) of Galactic
halo and bulge stars can be matched by varying a single evolutionary parameter,
nQ. Q is the filling factor of contaminating regions and n is the number of
star-forming generations. Therefore, Q and n have equivalent roles, and
combinations of n and Q yield systems with different metallicities at any given
age. The model also revises interpretation of observed MDFs. Unevolved systems
probe the parent distribution of metal production f(z), for example, the
high-metallicity tail of the halo distribution agrees with a power-law f(z).

</DOC>
<DOC>
<DOCNO> 178778 </DOCNO>
Algebraic model of baryon structure


  We discuss properties of baryon resonances belonging to the Nucleon, Delta,
Sigma, Lambda, Xi and Omega families in a collective string-like model for the
nucleon, in which the radial excitations are interpreted as rotations and
vibrations of the string configuration. We find good overall agreement with the
available data. The main discrepancies are found for low lying S-wave states,
in particular N(1535), N(1650), Sigma(1750), Lambda*(1405), Lambda(1670) and
Lambda(1800).

</DOC>
<DOC>
<DOCNO> 99798 </DOCNO>
On the convergence of formal mappings


  Let f : (M,p)\to (M',p') be a formal (holomorphic) nondegenerate map, i.e.
with formal holomorphic Jacobian J_f not identically vanishing, between two
germs of real analytic generic submanifolds in \C^n, p'=f(p). Assuming the
target manifold to be real algebraic, and the source manifold to be minimal at
p\in M in the sense of Tumanov, we prove the convergence of the so-called
reflection mapping associated to f. From this, we deduce the convergence of
such mappings from minimal real analytic generic submanifolds onto real
algebraic holomorphically nondegenerate ones, as well as related results on
partial convergence of such maps. For the proofs, we establish a principle of
analyticity for formal CR power series. This principle can be used to reobtain
the convergence of formal mappings between real analytic CR manifolds under a
standard nondegeneracy condition.

</DOC>
<DOC>
<DOCNO> 80701 </DOCNO>
Sea Quark Effects on Quarkonia


  We study the effects of two dynamical sea quarks on the spectrum of heavy
quarkonia. Within the non-relativistic approach to Lattice QCD we found
sizeable changes to the hyperfine splitting, but we could not observe any
changes for the fine structure. We also investigated the scaling behaviour of
our results for several different lattice spacings.

</DOC>
<DOC>
<DOCNO> 80678 </DOCNO>
A Lattice Study of the Glueball Spectrum


  Glueball spectrum is studied using an improved gluonic action on asymmetric
lattices in the pure SU(3) gauge theory. The smallest spatial lattice spacing
is about $0.08fm$ which makes the extrapolation to the continuum limit more
reliable. In particular, attention is paid to the scalar glueball mass which is
known to have problems in the extrapolation. Converting our lattice results to
physical units using the scale set by the static quark potential, we obtain the
following results for the glueball masses: $M_G(0^{++})=1730(90)MeV$ for the
scalar glueball mass and $M_G(2^{++})=2400(95)MeV$ for the tensor glueball.

</DOC>
<DOC>
<DOCNO> 69722 </DOCNO>
Dynamical Higher-Twist and High x Phenomena: A Window to Quark-Quark


  Measurements of the power-law corrections to Bjorken scaling and the behavior
of structure functions in the highly stressed $x_{bj} \to 1$ regime of
electroproduction can lead to new information on the quark-quark correlations
controlling the nucleon wavefunction at far-off-shell kinematics.
Electroproduction on nuclei at $ A > x_{bj} > 1$ is sensitive to hidden-color
components of the nuclear wavefunction. A distinctive dynamical higher-twist
${\cal O}(1/Q^2)$ correction, which is dynamically enhanced at high $x_{bj}$,
can arise from the interference of amplitudes where the lepton scatters from
two different valence quarks of the target. Measurements of the
parity-violating left-right asymmetry $A_{LR}$ in elastic and inelastic
polarized electron scattering at large $x_{bj}$ can confirm the structure of
the quark-quark correlations and other QCD physics at the amplitude level.

</DOC>
<DOC>
<DOCNO> 68166 </DOCNO>
B_c Decays and Lifetime in QCD Sum Rules


  In the framework of three-point QCD sum rules, the form factors for the
semileptonic decays of B_c --> B_s(B_s^*) l \nu are calculated with account for
the Coulomb-like alpha_s/v-corrections in the heavy quarkonium. The generalized
relations due to the spin symmetry of HQET/NRQCD for the form factors are
derived at the recoil momentum close to zero. The nonleptonic decays are
studied using the assumption on the factorization. The B_c meson lifetime is
estimated by summing up the dominating exclusive modes in the c --> s
transition combining the current calculations with the previous analysis of b
--> c decays in the sum rules of QCD and NRQCD.

</DOC>
<DOC>
<DOCNO> 9407 </DOCNO>
X-ray scattering study of two length scales in the critical fluctuations


  The critical fluctuations of CuGeO$_3$ have been measured by synchrotron
x-ray scattering, and two length scales are clearly observed. The ratio between
the two length scales is found to be significantly different along the $a$
axis, with the $a$ axis along the surface normal direction. We believe that
such a directional preference is a clear sign that surface random strains,
especially those caused by dislocations, are the origin of the long length
scale fluctuations.

</DOC>
<DOC>
<DOCNO> 71478 </DOCNO>
On the polarization properties of the charmed baryon Lambda^+_c in the


  The polarization properties of the charmed Lambda^+_c baryon are investigated
in weak non-leptonic four-body Lambda^+_c -> p + K^- + pi^+ + pi^0 decay. The
probability of this decay and the angular distribution of the probability are
calculated in the effective quark model with chiral U(3)XU(3) symmetry
incorporating Heavy Quark Effective theory (HQET) and the extended
Nambu-Jona-Lasinio model with a linear realization of chiral U(3)XU(3)
symmetry. The theoretical value of the probability of the decay Lambda^+_c -> p
+ K^- + pi^+ + pi^0 relative to the probability of the decay Lambda^+_c -> p +
K^- + pi^+ does not contain free parameters and fits well experimental data.
The application of the obtained results to the analysis of the polarization of
the Lambda^+_c produced in the processes of photo and hadroproduction is
discussed.

</DOC>
<DOC>
<DOCNO> 101975 </DOCNO>
On the Definition of Word Hyperbolic Groups


  Formal languages based on the multiplication tables of finitely generated
groups are investigated and used to give a linguistic characterization of word
hyperbolic groups.

</DOC>
<DOC>
<DOCNO> 40429 </DOCNO>
Black Hole Formation in Core-Collapse Supernovae and Time-of-Flight


  Early black hole formation in core-collapse supernovae may be triggered by
mass accretion or a change in the high-density equation of state. We consider
the possibility that black hole formation happens when the flux of neutrinos is
still measurably high. If this occurs, then the neutrino signal from the
supernova will be terminated abruptly (the transition takes $\lesssim 0.5$ ms).
The properties and duration of the signal before the cutoff are important
measures of both the physics and astrophysics of the cooling proto-neutron
star. For the event rates expected in present and proposed detectors, the
cutoff will generally appear sharp, thus allowing model-independent
time-of-flight mass tests for the neutrinos after the cutoff. If black hole
formation occurs relatively early, within a few ($\sim 1$) seconds after core
collapse, then the expected luminosities are of order $L_{BH} = 10^{52}$ erg/s
per flavor. In this case, the neutrino mass sensitivity can be extraordinary.
For a supernova at a distance $D = 10$ kpc, SuperKamiokande can detect a
$\bar{\nu}_e$ mass down to 1.8 eV by comparing the arrival times of the
high-energy and low-energy neutrinos in $\bar{\nu}_e + p \to e^+ + n$. This
test will also measure the cutoff time, and will thus allow a mass test of
$\nu_\mu$ and $\nu_\tau$ relative to $\bar{\nu}_e$. Assuming that $\nu_\mu$ and
$\nu_\tau$ are nearly degenerate, as suggested by the atmospheric neutrino
results, masses down to about 6 eV can be probed with a proposed lead detector
of mass $M_D = 4$ kton (OMNIS). Remarkably, the neutrino mass sensitivity
scales as $(D/L_{BH} M_D)^{1/2}$. Therefore, {\it direct} sensitivity to all
three neutrino masses in the interesting few-eV range is realistically
possible; {\it there are no other known techniques that have this capability}.

</DOC>
<DOC>
<DOCNO> 12976 </DOCNO>
Comment on "Analytical Structure of One Dimensional Localization Theory:


  In Phys. Rev. Lett. 84, 1760 (2000) A.O.Gogolin has challenged the
established point of view that Mott's law for the dynamical conductivity of a 1
dimensional insulator is correct. We present the result of a numerical solution
of Berezinskii's recursion relations that demonstrate unambigously that the
earlier solutions are indeed valid in contrast to Gogolin's claim.

</DOC>
<DOC>
<DOCNO> 11856 </DOCNO>
Bulk and Lattice Properties for Rigid Carbon Nanotubes Materials


  We use an atom-atom potential between carbon atoms to obtain an interaction
potential between nanotubes (assumed rigid), thereby calculating the cohesive
energy of a bunch of nanotubes in hexagonal two dimensional packing. The model
proposed is quite similar to our earlier work on fullerenes and organic
molecular crystals. The results for inter-nanotube distances, energy per unit
length, bulk modulus and phonons for inter-nanotube vibrations are obtained and
compared with available data from measurements and other available
calculations. We also model formation of multi-wall nanotubes. We find the
results for various calculated quantities agreeing very well with measured
structural parameters and other calculations. The reversible energy stored on
compression of the bunch of nanotubes on application of pressure up to 30 Kbar
calculated in this rigid molecule model is overestimated by about 30% when
compared with measured results, signifying the appreciable flexibility of tubes
at high pressures. The model is considered very suitable for incorporating
flexible nanotubes in bunches of single and multi-wall nanotube materials of
various types.

</DOC>
<DOC>
<DOCNO> 39971 </DOCNO>
QCD


  We discuss issues of QCD at the LHC including parton distributions, Monte
Carlo event generators, the available next-to-leading order calculations,
resummation, photon production, small x physics, double parton scattering, and
backgrounds to Higgs production.

</DOC>
<DOC>
<DOCNO> 151665 </DOCNO>
Dimensional regularization of nonlinear sigma models on a finite time


  We extend dimensional regularization to the case of compact spaces. Contrary
to previous regularization schemes employed for nonlinear sigma models on a
finite time interval (``quantum mechanical path integrals in curved space'')
dimensional regularization requires only a covariant finite two-loop
counterterm. This counterterm is nonvanishing and given by R/8.

</DOC>
<DOC>
<DOCNO> 170073 </DOCNO>
Quantum disentanglers


  It is not possible to disentangle a qubit in an unknown state $|\psi>$ from a
set of (N-1) ancilla qubits prepared in a specific reference state $|0>$. That
is, it is not possible to {\em perfectly} perform the transformation
$(|\psi,0...,0\r +|0,\psi,...,0\r +...+ |0,0,...\psi\r) \to |0,...,0>\otimes
|\psi>$. The question is then how well we can do? We consider a number of
different methods of extracting an unknown state from an entangled state formed
from that qubit and a set of ancilla qubits in an known state. Measuring the
whole system is, as expected, the least effective method. We present various
quantum ``devices'' which disentangle the unknown qubit from the set of ancilla
qubits. In particular, we present the optimal universal disentangler which
disentangles the unknown qubit with the fidelity which does not depend on the
state of the qubit, and a probabilistic disentangler which performs the perfect
disentangling transformation, but with a probability less than one.

</DOC>
<DOC>
<DOCNO> 100376 </DOCNO>
R\'esolutions de Demazure affines et formule de Casselman-Shalika


  We prove a conjecture of Frenkel, Gaitsgory, Kazhdan and Vilonen, related to
Fourier coefficients of spherical perverse sheaves on the affine Grassmannian
associated to a a split reductive group. Our proof is an extension of the proof
given by the first author in the case of GL(n) (see math/9801109); it relies on
the study of certain resolutions of Schubert varieties in the affine
Grassmannian, built from the so-called minuscule or quasi-minuscule cases.

</DOC>
<DOC>
<DOCNO> 151387 </DOCNO>
Topological Solitons in Discrete Space-Time as the Model of Fermions


  In the present paper we discuss arguments, favouring the view that massive
fermions represent dislocations (i.e. topological solitons) in discrete
space-time with Burgers vectors, parallel to an axis of time. If to put
symmetrical parts of tensors of distortions (i.e. derivatives of atomic
displacements on coordinates) and mechanical stresses equal zero, the equations
of the field theory of dislocations get the form of the Maxwell equations. If
to consider these tensors as symmetrical, we shall receive the equations of the
theory of gravitation, and it turns out that the sum of tensor of distortions
and pseudo-Euclidean metrical tensor is the analogue of metrical tensor. It is
shown that we can also get Dirac equation with four-fermion interaction in the
framework of the field theory of dislocations. This model explains quantization
of electrical charge: it is proportional to the topological charge of
dislocation, and this charge accepts quantized values because of discrete
structure of the 4-dimensional lattice.

</DOC>
<DOC>
<DOCNO> 12545 </DOCNO>
Invariance of Charge of Laughlin Quasiparticles


  A Quantum Antidot electrometer has been used in the first direct observation
of the fractionally quantized electric charge. In this paper we report
experiments performed on the integer i = 1, 2 and fractional f = 1/3 quantum
Hall plateaus extending over a filling factor range of at least 27%. We find
the charge of the Laughlin quasiparticles to be invariantly e/3, with standard
deviation of 1.2% and absolute accuracy of 4%, independent of filling,
tunneling current, and temperature.

</DOC>
<DOC>
<DOCNO> 116821 </DOCNO>
IHEP Experience on Creation and Operation of RFQS


  The new 1.8 MeV proton RFQ was completed and started operation in the IHEP in
1997. It was built according to the plan of modernization of the injection
system to the booster of the IHEP proton synchrotron.

</DOC>
<DOC>
<DOCNO> 151968 </DOCNO>
No consistent cross-interactions for a collection of massless spin-2


  We report a no-go theorem excluding consistent cross-couplings for a
collection of massless, spin-2 fields described, in the free limit, by the sum
of Pauli-Fierz actions (one for each field). We show that, in spacetime
dimensions >2, there is no consistent coupling, with at most two derivatives of
the fields, that can mix the various "gravitons". The only possible
deformations are given by the sum of individual Einstein-Hilbert actions (one
for each field) with cosmological terms. Our approach is based on the
BRST-based deformation point of view.

</DOC>
<DOC>
<DOCNO> 69062 </DOCNO>
Physics Impact of GigaZ


  By running the prospective high-energy e^+ e^- collider TESLA in the GigaZ
mode on the Z resonance, experiments can be performed on the basis of more than
10^9 Z events. They will allow the measurement of the effective electroweak
mixing angle to an accuracy of approximately +- 10^-5. Likewise the W boson
mass is expected to be measurable with an error of about 6 MeV near the W^+ W^-
threshold. In this note, we study the accuracy with which the Higgs boson mass
can be determined from loop corrections to these observables in the Standard
Model. The comparison with a directly observed Higgs boson may be used to
constrain new physics scales affecting the virtual loops. We also study
constraints on the heavy Higgs particles predicted in the Minimal
Supersymmetric Standard Model, which are very difficult to observe directly for
large masses. Similarly, it is possible to constrain the mass of the heavy
scalar top particle.

</DOC>
<DOC>
<DOCNO> 83346 </DOCNO>
Temiar Reduplication in One-Level Prosodic Morphology


  Temiar reduplication is a difficult piece of prosodic morphology. This paper
presents the first computational analysis of Temiar reduplication, using the
novel finite-state approach of One-Level Prosodic Morphology originally
developed by Walther (1999b, 2000). After reviewing both the data and the basic
tenets of One-level Prosodic Morphology, the analysis is laid out in some
detail, using the notation of the FSA Utilities finite-state toolkit (van Noord
1997). One important discovery is that in this approach one can easily define a
regular expression operator which ambiguously scans a string in the left- or
rightward direction for a certain prosodic property. This yields an elegant
account of base-length-dependent triggering of reduplication as found in
Temiar.

</DOC>
<DOC>
<DOCNO> 169778 </DOCNO>
Berry's Phase in the Presence of a Dissipative Medium


  We consider the spin 1/2 model coupled to a slowly varying magnetic field in
the presence of a weak damping represented by a Lindblad-form operators. We
show that Berry's geometrical phase remains unaltered by the two dissipation
mechanism considered. Dissipation effects are twofold: a shrinking in the
modulus of the Bloch's vector, which characterizes coherence loss and a time
dependent (dissipation related) precession angle. We show that the line
broadening of the Fourier transformation of the components of magnetization is
only due to the presence of dissipation.

</DOC>
<DOC>
<DOCNO> 152521 </DOCNO>
New topological field theories in two dimensions


  It is shown that two$(1 + 1)$-dimensional (2D) free Abelian- and
self-interacting non-Abelian gauge theories (without any interaction with
matter fields) belong to a new class of topological field theories. These new
theories capture together some of the key features of Witten- and Schwarz type
of topological field theories because they are endowed with symmetries that are
reminiscent of the Schwarz type theories but their Lagrangian density has the
appearance of the Witten type theories. The topological invariants for these
theories are computed on a 2D compact manifold and their recursion relations
are obtained. These new theories are shown to provide a class of tractable
field theoretical models for the Hodge theory in two dimensions of flat
(Minkowski) spacetime where there are no propagating degrees of freedom
associated with the 2D gauge boson.

</DOC>
<DOC>
<DOCNO> 116731 </DOCNO>
Effective ATI Channels in High Harmonic Generation


  Harmonic generation by an atom in a laser field is described by the
three-step mechanism as proceeding via above-threshold ionization (ATI)
followed by the electron propagation in the laser-dressed continuum and the
subsequent laser assisted recombination (LAR). An amplitude of harmonic
production is given by the coherent sum of contributions from different
intermediate ATI channels labeled by the number m of absorbed laser photons.
The range of m-values that gives substantial contribution is explored and found
to be rather broad for high harmonic generation. The coherence effects are of
crucial importance being responsible for the characteristic pattern of harmonic
intensities with a plateau domain followed by a cutoff region. Due to
multiphoton nature of the process, an efficient summation of m-contributions
can be carried out in the framework of the saddle point method. The saddle
points correspond to some complex-valued labels m=m_c associated with the
intermediate effective ATI channels in the three-step harmonic generation
process. The advantage of this approach stems from the fact that summation over
large number of conventional ATI m-channels is replaced by summation over small
number of effective m_c-channels. The equation governing m_c has a transparent
physical meaning: the electron ejected from the atom on the first (ATI) stage
should return to the core to make LAR possible. The calculated rates are in
good agreement with the results obtained by other approaches.

</DOC>
<DOC>
<DOCNO> 11651 </DOCNO>
Measuring Fractional Charge in Carbon Nanotubes


  The Luttinger model of the one-dimensional Fermi gas is the cornerstone of
modern understanding of interacting electrons in one dimension. In fact, the
enormous class of systems whose universal behavior is adiabatically connected
to it are now deemed Luttinger liquids. Recently, it has been shown that
metallic single-walled carbon nanotubes are almost perfectly described by the
Luttinger Hamiltonian. Indeed, strongly non-Fermi liquid behavior has been
observed in a variety of DC transport experiments, in very good agreement with
theoretical predictions. Here, we describe how fractional quasiparticle charge,
a fundamental property of Luttinger liquids, can be observed in
impurity-induced shot noise.

</DOC>
<DOC>
<DOCNO> 68786 </DOCNO>
Answering the Sphinx's Questions on Neutrinos


  In answering the difficult questions on neutrinos asked by Sphinx I argue
that search for proton decay is the most important experiment in coming 5-10
years. I also emphasize the crucial importance of the neutrinoless double beta
decay with sensitivity of <m_{\nu e}> \sim 0.01 eV level as the unique feasible
way of directly detecting neutrinos of atmospheric mass scale in laboratories.
I point out that, if observed at this level, it means not only that neutrinos
are Majorana particle but also that they must obey an inverted mass hierarchy.

</DOC>
<DOC>
<DOCNO> 116372 </DOCNO>
Physical model of Hadrons : Barions and mesons. Physical essence of


  The physical model (PhsMdl) of the hadrons is offered by means of the obvious
analogy with the transparent surveyed PhsMdls of the vacuum and leptons in our
recent works. It is assumed that the vacuum is consistent by dynamides,
streamlined in junctions of some tight crystalline lattice. Every dynamide
contains a neutral pair of massless contrary point-like (PntLk) elementary
electric charges (ElmElc Chrgs): electrino $(-)$ and positrino $(+)$. By means
of the existent fundamental analogy between their properties and behaviour we
can understand the similarity and difference between them and assume that the
quark parameter aroma is determined by the value of its size of its circular
two-dimensional motion, while the quark parameter colour is determined by
orientation of the flat of the same circular two-dimensional motion in the
space. The colorless of the barions is explained by distribution of the same
circular two-dimensional motion of its elementary electric charge within three
mutually perpendicular flats. Then the exchange of the colors between two
quarks with different colors within some hadron can be interpretated as some
twisting of same hadron in the space. We give a new obvious physical
interpretation of the charge values of quarks, which gives some explanation of
angles of Cabibo and Weynberg. By some physical supposition about the structure
of charged intermediate vector bozon $W$ and uncharged intermediate vector
bozon $Z$ we have possibility to explain as the physical essence of the strong,
weak and electromagnetic interactions, so the outline of all births,
transformations and decays of the ElmPrts.

</DOC>
<DOC>
<DOCNO> 83482 </DOCNO>
Do All Fragments Count?


  We aim at finding the minimal set of fragments which achieves maximal parse
accuracy in Data Oriented Parsing. Experiments with the Penn Wall Street
Journal treebank show that counts of almost arbitrary fragments within parse
trees are important, leading to improved parse accuracy over previous models
tested on this treebank. We isolate a number of dependency relations which
previous models neglect but which contribute to higher parse accuracy.

</DOC>
<DOC>
<DOCNO> 117296 </DOCNO>
Space-Time Exchange Invariance: Special Relativity as a Symmetry


  Special relativity is reformulated as a symmetry property of space-time:
Space-Time Exchange Invariance. The additional hypothesis of spatial
homogeneity is then sufficient to derive the Lorentz transformation without
reference to the traditional form of the Principle of Special Relativity. The
kinematical version of the latter is shown to be a consequence of the Lorentz
transformation. As a dynamical application, the laws of electrodynamics and
magnetodynamics are derived from those of electrostatics and magnetostatics
respectively. The 4-vector nature of the electromagnetic potential plays a
crucial role in the last two derivations.

</DOC>
<DOC>
<DOCNO> 119822 </DOCNO>
Fine phase resolved spectroscopy of the X-ray emission of the Crab


  The Crab Nebula and the Pulsar have been pointed several times by the
BeppoSAX satellite. We analysed all these observations, summed together, to
study the main spectral properties with a good phase resolution. A new accurate
estimate of the hydrogen column density in the Crab direction N_H=3.23 x
10^(21) cm^(-2) is given as derived from the analysis of the off-pulse emission
at low energies. We studied the changes of the spectral index with the pulse
phase and showed that in the interpeak region it is systematically harder than
in the main peaks of about 0.4. We observed also a significant spectral
steepening of the pulsed emission and showed that this distribution can be
represented by a unique law with a linear variable log slope and apply it to
the spectrum of the first peak. A two component model is proposed to explain
the phase evolution of the spectrum. One component has the same profile
observed in the optical while the other presents a maximum at the phase 0.4
with essentially the spectrum of the interpeak region. Two possible
interpretations for the origin of the latter component are discussed.

</DOC>
<DOC>
<DOCNO> 10698 </DOCNO>
Critical point for the strong field magnetoresistance of a normal


  A recently developed self-consistent effective medium approximation, for
composites with a columnar microstructure, is applied to such a
three-constituent mixture of isotropic normal conductor, perfect insulator, and
perfect conductor, where a strong magnetic field {\bf B} is present in the
plane perpendicular to the columnar axis. When the insulating and perfectly
conducting constituents do not percolate in that plane, the
microstructure-induced in-plane magnetoresistance is found to saturate for
large {\bf B}, if the volume fraction of the perfect conductor $p_S$ is greater
than that of the perfect insulator $p_I$. By contrast, if $p_S<p_I$, that
magnetoresistance keeps increasing as ${\bf B}^2$ without ever saturating. This
abrupt change in the macroscopic response, which occurs when $p_S=p_I$, is a
critical point, with the associated critical exponents and scaling behavior
that are characteristic of such points. The physical reasons for the singular
behavior of the macroscopic response are discussed. A new type of percolation
process is apparently involved in this phenomenon.

</DOC>
<DOC>
<DOCNO> 84232 </DOCNO>
Adaptive filtering techniques for interferometric data preparation:


  We propose an adaptive denoising scheme for poorly modeled non-Gaussian
features in the gravitational wave interferometric data. Preliminary tests on
real data show encouraging results.

</DOC>
<DOC>
<DOCNO> 71071 </DOCNO>
The Standard Model prediction for eps'/eps


  We review fundamental aspects of a new Standard Model analysis of eps'/eps
which takes into account the strong enhancement induced by final state
interactions.

</DOC>
<DOC>
<DOCNO> 8160 </DOCNO>
Phase-sensitive Evidence for d-wave Pairing Symmetry in Electron-doped


  We present phase-sensitive evidence that the electron-doped cuprates
Nd1.85Ce0.15CuO4-y (NCCO) and Pr1.85Ce0.15CuO4-y (PCCO) have d-wave pairing
symmetry. This evidence was obtained by observing the half-flux quantum effect,
using a scanning SQUID microscope, in c-axis oriented films of NCCO or PCCO
epitaxially grown on tricrystal [100] SrTiO3 substrates designed to be
frustrated for a d(x2-y2) order parameter. Samples with two other
configurations, designed to b unfrustrated for a d-wave superconductor, do not
show the half-flux quantum effect.

</DOC>
<DOC>
<DOCNO> 69560 </DOCNO>
Supersymmetric Nonlinear Sigma Models


  Supersymmetric nonlinear sigma models are formulated as gauge theories.
Auxiliary chiral superfields are introduced to impose supersymmetric
constraints of F-type. Target manifolds defined by F-type constraints are
always non-compact. In order to obtain nonlinear sigma models on compact
manifolds, we have to introduce gauge symmetry to eliminate the degrees of
freedom in non-compact directions. All supersymmetric nonlinear sigma models
defined on the hermitian symmetric spaces are successfully formulated as gauge
theories.

</DOC>
<DOC>
<DOCNO> 70625 </DOCNO>
Cosmological Constant or Cosmological Potential


  In the framework of a model of minimal of dilatonic gravity (MDG) with
cosmological potential we consider: the relations of MDG with nonlinear gravity
and string theory; natural cosmological units, defined by cosmological
constant; the properties of cosmological factor, derived from solar system and
Earth-surface gravitational experiments; universal anty-gravitational
interactions, induced by positive cosmological constant and by Nordtved effect;
a new formulation of cosmological constant problem using the ratio of
introduced cosmological action and Planck constant $\sim 10 ^{122}$;qualitative
analysis of this huge number based on classical action of effective Bohr
hydrogen atoms; inverse cosmological problem: to find cosmological potential
which yields given evolution of the RW Universe; and comment other general
properties of MDG.

</DOC>
<DOC>
<DOCNO> 101265 </DOCNO>
The Lattice of integer partitions and its infinite extension


  In this paper, we use a simple discrete dynamical system to study the
integers partitions and their lattice. The set of the reachable configurations
equiped with the order induced by the transitions of the system is exactly the
lattice of integer partitions equiped with the dominance ordering. We first
explain how this lattice can be constructed, by showing its strong
self-similarity property. Then, we define a natural extension of the system to
infinity. Using a self-similar tree, we obtain an efficient coding of the
obtained lattice. This approach gives an interesting recursive formula for the
number of partitions of an integer, where no closed formula have ever been
found. It also gives informations on special sets of partitions, such as length
bounded partitions.

</DOC>
<DOC>
<DOCNO> 69658 </DOCNO>
Suppressing Flavor Anarchy


  We present a new mechanism, which does not require any flavor symmetry, to
explain the small Yukawa couplings and CKM mixing angles. The Yukawa matrices
are assumed to be random at short distances and the hierarchical structure is
generated in the infrared by renormalization group flow. The generic
qualitative predictions of this mechanism are in good agreement with
observation. We give several simple examples in supersymmetric theories. We
show that our mechanism can also ameliorate the supersymmetric flavor problem,
and make predictions for the superpartner mass spectrum. The mechanism is fully
consistent with grand unification, and in SU(5)-based models of neutrino mass,
predicts a large mixing angle for muon neutrino to tau neutrino oscillations.

</DOC>
<DOC>
<DOCNO> 67782 </DOCNO>
Minimal Gaugino Mediation


  We propose Minimal Gaugino Mediation as the simplest known solution to the
supersymmetric flavor and CP problems. The framework predicts a very minimal
structure for the soft parameters at ultra-high energies: gaugino masses are
unified and non-vanishing whereas all other soft supersymmetry breaking
parameters vanish. We show that this boundary condition naturally arises from a
small extra dimension and present a complete model which includes a new
extra-dimensional solution to the mu problem. We briefly discuss the predicted
superpartner spectrum as a function of the two parameters of the model. The
commonly ignored renormalization group evolution above the GUT scale is crucial
to the viability of Minimal Gaugino Mediation but does not introduce new model
dependence.

</DOC>
<DOC>
<DOCNO> 13087 </DOCNO>
Scaling approach to order-parameter fluctuations in disordered


  We present a constructive approach to obtain information about the
compactness and shape of large-scale lowest excitations in disordered systems
by studying order-parameter fluctuations (OPF) at low temperatures. We show
that the parameter $G$ which measures OPF is 1/3 at T=0 provided the ground
state is unique and the probability distribution for the lowest excitations is
gapless and with finite weight at zero-excitation energy. We then apply
zero-temperature scaling to describe the energy and volume spectra of the
lowest large-scale excitations which scale with the system size and have a
weight at ze ro energy $\hat{P}_v(0)\sim l^{-\theta'}$ with $v=l^d$. A
low-temperature expansion reveals that, OPF vanish like $L^{-\theta}$, if
$\theta> 0$ and remain finite for space filling lowest excitations with
$\theta=0$. The method can be extended to extract information about the shape
and fractal surface of the large-scale lowest excitations.

</DOC>
<DOC>
<DOCNO> 117439 </DOCNO>
Advection-dominated Inflow/Outflows from Evaporating Accretion Disks


  In this Letter we investigate the properties of advection-dominated accretion
flows (ADAFs) fed by the evaporation of a Shakura-Sunyaev accretion disk (SSD).
In our picture the ADAF fills the central cavity evacuated by the SSD and
extends beyond the transition radius into a coronal region. We find that,
because of global angular momentum conservation, a significant fraction of the
hot gas flows away from the black hole forming a transsonic wind, unless the
injection rate depends only weakly on radius (if $r^2\dot\sigma\propto
r^{-\xi}$, $\xi< 1/2$). The Bernoulli number of the inflowing gas is negative
if the transition radius is $\lesssim 100$ Schwarzschild radii, so matter
falling into the hole is gravitationally bound. The ratio of inflowing to
outflowing mass is $\approx 1/2$, so in these solutions the accretion rate is
of the same order as in standard ADAFs and much larger than in
advection-dominated inflow/outflow models (ADIOS). The possible relevance of
evaporation-fed solutions to accretion flows in black hole X-ray binaries is
briefly discussed.

</DOC>
<DOC>
<DOCNO> 39858 </DOCNO>
Determining the Flavour Content of the Low-Energy Solar Neutrino Flux


  We study the sensitivity of the HELLAZ and Borexino solar neutrino
experiments on discriminating the neutrino species nu_e, anti-nu_e,
nu_{mu,tau}, anti-nu_{mu,tau}, and nu_{sterile} using the difference in the
recoil electron kinetic energy spectra in elastic neutrino-electron scattering.
We find that one can observe a non-vanishing nu_{mu,tau} component in the solar
neutrino flux, especially when the nu_e survival probability is low. Also, if
the data turn out to be consistent with nu_e <-> nu_{mu,tau} oscillations, an
anti-nu_e component can be excluded effectively.

</DOC>
<DOC>
<DOCNO> 70291 </DOCNO>
Affleck-Dine Leptogenesis with an Ultralight Neutrino


  We perform a detailed analysis on Affleck-Dine leptogenesis taking into
account the thermal effects on the dynamics of the flat direction field $\phi$.
We find that an extremely small mass for the lightest neutrino $\nu_1$,
${m_\nu}_1\lsim 10^{-8}$ eV, is required to produce enough lepton-number
asymmetry to explain the baryon asymmetry in the present universe. We impose
here the reheating temperature after inflation $T_R$ to be $T_R\lsim 10^8$ GeV
to solve the cosmological gravitino problem. The required value of neutrino
mass seems to be very unlikely the case since the recent Superkamiokande
experiments suggest the masses of heavier two neutrinos $\nu_2$ and $\nu_3$ to
be in a range of $10^{-1}$--$10^{-3}$ eV. We also propose a model to avoid this
difficulty based on the Peccei-Quinn symmetry, where the required neutrino mass
can be as large as ${m_\nu}_1\simeq 10^{-4}$ eV.

</DOC>
<DOC>
<DOCNO> 123239 </DOCNO>
The Second APM UKST Colour Survey for z>4 Quasars


  We present the spectra, positions, and finding charts for 31 bright (R<19.3)
colour-selected quasars covering the redshift range z=3.85-4.78, with 4 having
redshifts z>4.5. The majority are in the southern sky (dec<-25 deg). The quasar
candidates were selected for their red (B-R > 2.5) colours from UK or POSSII
Schmidt Plates scanned at the Automated Plate Measuring facility in Cambridge.
Low resolution (~> 10A) spectra were obtained to identify the quasars,
primarily at the Las Campanas Observatory. The highest redshift quasar in our
survey is at z ~ 4.8 (R = 18.7) and its spectrum shows a damped Lyman-alpha
absorption system at z = 4.46. This is currently the highest redshift damped
Lyman-alpha absorber detected. Five of these quasars exhibit intrinsic broad
absorption line features. Combined with the previously published results from
the first part of the APM UKST survey we have now surveyed a total of ~8000 squ
deg of sky i.e. 40% of the high galactic latitude (|b|>30 deg) sky, resulting
in 59 optically selected quasars in the redshift range 3.85 to 4.78; 49 of
which have z>=4.00.

</DOC>
<DOC>
<DOCNO> 83121 </DOCNO>
SLDNFA-system


  The SLDNFA-system results from the LP+ project at the K.U.Leuven, which
investigates logics and proof procedures for these logics for declarative
knowledge representation. Within this project inductive definition logic
(ID-logic) is used as representation logic. Different solvers are being
developed for this logic and one of these is SLDNFA. A prototype of the system
is available and used for investigating how to solve efficiently problems
represented in ID-logic.

</DOC>
<DOC>
<DOCNO> 10647 </DOCNO>
Quasiparticle relaxation dynamics in cuprates and lifetimes of


  We show that low-energy spectral features in the cuprates can be separated
into different components by the measurement of the recombination dynamics of
different low-energy excitations in real-time using femtosecond laser
spectroscopy. Quasiparticle (QP) recombination across the gap and intra-gap
localized state relaxation processes exhibit qualitatively different time- and
temperature-dependences. The relaxation measurements also show the existence of
two distinct coexisting energy gaps near optimum doping and in the overdoped
region, one more or less temperature independent (which exists above and below
Tc) and one which closes at Tc in a mean-field like fashion. Thus systematic
studies of QP recombination as a function of doping and temperature suggest
that the ground state of the cuprates is a mixed Boson-Fermion system with
localised states present over the entire region of the phase diagram.

</DOC>
<DOC>
<DOCNO> 13535 </DOCNO>
Static hole in a critical antiferromagnet: field-theoretic


  We consider the quantum field theory of a single, immobile, spin S hole
coupled to a two-dimensional antiferromagnet at a bulk quantum critical point
between phases with and without magnetic long-range order. We present an
alternative derivation of its two-loop beta function; the results agree
completely with earlier work (M. Vojta et al, cond-mat/9912020), and also
determine a new anomalous dimension of the hole creation operator.

</DOC>
<DOC>
<DOCNO> 170235 </DOCNO>
Quantum codes on high-genus surfaces


  An economy of scale is found when storing many qubits in one highly entangled
block of a topological quantum code. The code is defined by construction of a
topologically convoluted 2-d surface and does not work by compressing
redundancy in the encoded information.

</DOC>
<DOC>
<DOCNO> 100975 </DOCNO>
Local cohomology of generalized Okamoto-Painlev\'e pairs and Painlev\'e


  In the theory of deformation of Okamoto-Painlev\'e pair (S,Y), a local
cohomology group $H^1_D(\Theta_S(-\log D))$ plays an important role. In this
paper, we estimate the local cohomology group of pair (S,Y) for several types,
and obtain the following results. For a pair (S,Y) corresponding to the space
of initial conditions of the Painlev\'e equations, we show that the local
cohomology group $H^1_D(\Theta_S(-\log D))$ is at least 1 dimensional. This
fact is the key to understand Painlev\'e equation related to (S,Y). Moreover we
show that, for the pairs (S,Y) of type $\tilde{A_8}$, the local cohomology
group $H^1_D(\Theta_S(-\log D))$ vanish. Therefore in this case, there is no
differential equation on S-Y in the sense of the theory.

</DOC>
<DOC>
<DOCNO> 123165 </DOCNO>
Photometric evolution of dusty starburst mergers:On the nature of


  By performing N-body simulations of chemodynamical evolution of galaxies with
dusty starbursts, we investigate photometric evolution of gas-rich major
mergers in order to explore the nature of ultraluminous infrared galaxies
(ULIRGs) with the total infrared luminosity ($L_{\rm IR}$ for $8\sim 1000$
$\mu$m) of $\sim$ $10^{12}$ $L_{\odot}$. Main results are the following three.
(1) Global colors and absolute magnitudes the during dusty starburst of a major
merger do not change with time significantly, because interstellar dust heavily
obscures young starburst populations that could cause rapid evolution of
photometric properties of the merger. (2) Dust extinction of stellar
populations in a galaxy merger with large infrared luminosity ($L_{\rm IR}$ $>$
$10^{11}$ $L_{\odot}$) is selective in the sense that younger stellar
populations are preferentially obscured by dust than old ones. This is because
younger populations are located in the central region where a larger amount of
dusty interstellar gas can be transferred from the outer gas-rich regions of
the merger. (3) Both $L_{\rm IR}$ and the ratio of $L_{\rm IR}$ to $B$ band
luminosity $(L_{\rm B}$) increases as the star formation rate increase during
the starburst of the present merger model, resulting in the positive
correlation between $L_{\rm IR}$ and $L_{\rm IR}/L_{\rm B}$.

</DOC>
<DOC>
<DOCNO> 69340 </DOCNO>
Calculational techniques (not only) for single top production


  A next-to-leading order calculation for single top production including
spin-dependent observables requires efficient techniques for the calculation of
the relevant loop amplitudes. We discuss the adaption of dimensional
regularization, the spinor helicity method and of tensor integral reduction
algorithms to these needs.

</DOC>
<DOC>
<DOCNO> 80747 </DOCNO>
Anomalous Chiral Behavior in Quenched Lattice QCD


  A study of the chiral behavior of pseudoscalar masses and decay constants is
carried out in quenched lattice QCD with Wilson fermions. Using the modified
quenched approximation (MQA) to cure the exceptional configuration problem,
accurate results are obtained for pion masses as low as $\approx$ 200 MeV. The
anomalous chiral log effect associated with quenched $\eta'$ loops is studied
in both the relation between $m_{\pi}^2$ vs. $m_q$ and in the light-mass
behavior of the pseudoscalar and axial vector matrix elements. The size of
these effects agrees quantitatively with a direct measurement of the $\eta'$
hairpin graph, as well as with a measurement of the topological susceptibility,
thus providing several independent and quantitatively consistent determinations
of the quenched chiral log parameter $\delta$. For $\beta=5.7$ with
clover-improved fermions $(C_{sw} =1.57)$ all results are consistent with
$\delta=0.065\pm 0.013$ .

</DOC>
<DOC>
<DOCNO> 99695 </DOCNO>
On quadratic and higher normality of small codimension projective


  Ran proved that smooth codimension 2 varieties in ${\bf P}^{m+2}$ are
$j$-normal if $(j+1)(3j-1)\le m-1$, in this paper we extend this result to
small codimension projective varieties. Let $X$ be a r codimension subvariety
of $\pro$, we prove that if the set $\Sigma_{(j+1)}$ of $(j+1)$-secants to $X$
through a generic external point is not empty, $2(r+1)j\leq m-r$ and
$(j+1)((r+1)j-1)\leq m-1$ then $X$ is $j$-normal. If $X$ is given by the zero
locus of a section of a rank $r$ vector bundle $E$ on $\pro$, we prove that
$\textrm{deg} \Sigma_{j+1}=\frac{1}{(j+1)!}\prod_{i=0}^{j}c_{r}(E(-i))$.
Moreover we get a new simple proof of Zak's theorem on linear normality if
$m\ge 3r$. Finally we prove that if $c_{r}(N(-2))\neq 0$ and $6r\le m-4$ then
$X$ is 2-normal.

</DOC>
<DOC>
<DOCNO> 68235 </DOCNO>
Casimir Effect Between World-Branes in Heterotic M-Theory


  We study a non-supersymmetric $E_8\times\bar E_8$ compactification of
M-theory on $S^1/Z_2$, related to the supersymmetric $E_8\times E_8$ theory by
a chirality flip at one of the boundaries. This system represents an M-theory
analog of the D-brane anti-D-brane systems of string theory. Alternatively,
this compactification can be viewed as a model of supersymmetry breaking in the
``brane-world'' approach to phenomenology. We calculate the Casimir energy of
the system at large separations, and show that there is an attractive Casimir
force between the $E_8$ and $\bar E_8$ boundary. We predict that a tachyonic
instability develops at separations of order the Planck scale, and discuss the
possibility that the M-theory fivebrane might appear as a topological defect
supported by the $E_8\times\bar E_8$ system. Finally, we analyze the eventual
fate of the configuration, in the semiclassical approximation at large
separations: the two ends of the world annihilate by nucleating wormholes
between the two boundaries.

</DOC>
<DOC>
<DOCNO> 39616 </DOCNO>
The Search for Fractional Charge Elementary Particles and Very Massive


  We describe our ongoing work on, and future plans for, searches in bulk
matter for fractional charge elementary particles and very massive elementary
particles. Our primary interest is in searching for such particles that may
have been produced in the early universe and may be found in the more primeval
matter available in the solar system: meteorites, material from the moon's
surface, and certain types of ancient terrestrial rocks. In the future we are
interested in examining material brought back by sample return probes from
asteroids. We will describe our experimental methods that are based on new
modifications of the Millikan liquid drop technique and modern technology:
micromachining, CCD cameras, and desktop computers. Extensions of our
experimental methods and technology allow searches for very massive charged
particles in primeval matter; particles with masses greater than 10**13 GeV. In
the first such searches carried out on earth there will be uncertainties in the
mass search range. Therefore we will also discuss the advantages of eventually
carrying out such searches directly on an asteroid.

</DOC>
<DOC>
<DOCNO> 170487 </DOCNO>
Unitary transformations for testing Bell inequalities


  It is shown that optical experimental tests of Bell inequality violations can
be described by SU(1,1) transformations of the vacuum state, followed by photon
coincidence detections. The set of all possible tests are described by various
SU(1,1) subgroups of Sp(8,$\Bbb R$). In addition to establishing a common
formalism for physically distinct Bell inequality tests, the similarities and
differences of post--selected tests of Bell inequality violations are also made
clear. A consequence of this analysis is that Bell inequality tests are
performed on a very general version of SU(1,1) coherent states, and the
theoretical violation of the Bell inequality by coincidence detection is
calculated and discussed. This group theoretical approach to Bell states is
relevant to Bell state measurements, which are performed, for example, in
quantum teleportation.

</DOC>
<DOC>
<DOCNO> 101129 </DOCNO>
Mapping Integer Order Neumann Functions To Real Orders


  In a recent paper we unified Bessel functions of different orders .Here we
extend the unification to other linairely independant solutions to Bessel
equation, Neumann's and Hankel's functions

</DOC>
<DOC>
<DOCNO> 121544 </DOCNO>
Black Hole Demographics from the M(BH)-sigma Relation


  We analyze a sample of 32 galaxies for which a dynamical estimate of the mass
of the hot stellar component, M_bulge, is available. For each of these
galaxies, we calculate the mass of the central black hole, M_BH, using the
tight empirical correlation between M_BH and the bulge stellar velocity
dispersion. The frequency function N(log M_BH/M_bulge) is reasonably well
described as a Gaussian with <log M_BH/M_bulge> ~ -2.90 and standard deviation
0.45; the implied mean ratio of black hole to bulge mass is a factor 5 smaller
than generally quoted in the literature. We present marginal evidence for a
lower, average black-hole mass fraction in more massive galaxies. The total
mass density in black holes in the local Universe is estimated to be 5 x 10^5
solar masses per cubic megaparsec, consistent with that inferred from high
redshift (z ~ 2) AGNs.

</DOC>
<DOC>
<DOCNO> 121736 </DOCNO>
Complex Phase Lag Behaviors of the 0.5 - 10 Hz QPOs in GRS 1915+105


  Through studying the hard lags between the soft (3.3 - 5.8 keV) and hard
(13.0 - 41.0 keV) photons of the 0.5 - 10 Hz QPOs in GRS 1915+105, we have
classified them into three types: 0.5 - 2.0 Hz QPOs, 2.0 - 4.5 Hz QPOs, and 4.5
- 10 Hz QPOs. They are closely related to different temporal and spectral
states. The first type of QPOs (0.5 - 2 Hz) have positive hard lags at both the
QPO fundamental and first harmonic frequencies. These QPOs were observed in the
quiescent soft state. The second type of QPOs (2 - 4.5 Hz), which were also
detected in the quiescent soft state, have opposite signs of hard lags at the
QPO fundamental and first harmonic frequencies. The third type (4.5 - 10 Hz),
which showed up in medium soft quiescent/out-burst states, do not have
significant higher harmonic peaks. There is a smooth transition between these
three types of QPO behaviors. We did not detect 0.5 - 10 Hz QPOs in the very
soft state. We discuss some of the implications of these results.

</DOC>
<DOC>
<DOCNO> 11047 </DOCNO>
Stochastic reconstruction of sandstones


  A simulated annealing algorithm is employed to generate a stochastic model
for a Berea and a Fontainebleau sandstone with prescribed two-point probability
function, lineal path function, and ``pore size'' distribution function,
respectively. We find that the temperature decrease of the annealing has to be
rather quick to yield isotropic and percolating configurations. A comparison of
simple morphological quantities indicates good agreement between the
reconstructions and the original sandstones. Also, the mean survival time of a
random walker in the pore space is reproduced with good accuracy. However, a
more detailed investigation by means of local porosity theory shows that there
may be significant differences of the geometrical connectivity between the
reconstructed and the experimental samples.

</DOC>
<DOC>
<DOCNO> 116381 </DOCNO>
From the Neutrino to the Edge of the Universe


  Two recent findings necessitate a closer look at the existing standard models
of Particle Physics and Cosmology. These are the discovery of Neutrino
oscillation, and hence a non zero mass on the one hand and, on the other,
observations of distant supernovae which indicate that contrary to popular
belief, the universe would continue to expand for ever, possibly accelerating
in the process. In this paper it is pointed out that relatively recent studies
which indicate a stochastic, quantum vacuum underpinning and a fractal
structure for space time, reconcile both of the recent observations,
harmoniously.

</DOC>
<DOC>
<DOCNO> 85221 </DOCNO>
Thermoelastic effects at low temperatures and quantum limits in


  The displacement fluctuations of mirrors in optomechanical devices, induced
via thermal expansion by temperature fluctuations due either to thermodynamic
fluctuations or to fluctuations in the photon absorption, can be made smaller
than quantum fluctuations, at the low temperatures, high reflectivities and
high light powers needed to readout displacements at the standard quantum
limit. The result is relevant for the design of quantum limited
gravitational-wave detectors, both "interferometers" and "bars", and for
experiments to study directly mechanical motion in the quantum regime.

</DOC>
<DOC>
<DOCNO> 80671 </DOCNO>
Non-perturbative beta-function in SU(2) lattice gauge fields


  The new method of nonperturbative calculation of the beta function in the
lattice gauge theory is proposed. The method is based on the finite size
scaling hypothesis.

</DOC>
<DOC>
<DOCNO> 83423 </DOCNO>
Oracle Complexity and Nontransitivity in Pattern Recognition


  Different mathematical models of recognition processes are known. In the
present paper we consider a pattern recognition algorithm as an oracle
computation on a Turing machine. Such point of view seems to be useful in
pattern recognition as well as in recursion theory. Use of recursion theory in
pattern recognition shows connection between a recognition algorithm comparison
problem and complexity problems of oracle computation. That is because in many
cases we can take into account only the number of sign computations or in other
words volume of oracle information needed. Therefore, the problem of
recognition algorithm preference can be formulated as a complexity optimization
problem of oracle computation. Furthermore, introducing a certain "natural"
preference relation on a set of recognizing algorithms, we discover it to be
nontransitive. This relates to the well known nontransitivity paradox in
probability theory.
  Keywords: Pattern Recognition, Recursion Theory, Nontransitivity, Preference
Relation

</DOC>
<DOC>
<DOCNO> 84345 </DOCNO>
Asymptotic singular behavior of Gowdy spacetimes in string theory


  We study $T^{3}$ Gowdy spacetimes in the Einstein-Maxwell-dilaton-axion
system and show by the Fuchsian algorithm that they have in general
asymptotically velocity-term dominated singularities. The families of the
corresponding solutions depend on the maximum number of arbitrary functions.
Although coupling of the dilaton field with the Maxwell and/or the axion fields
corresponds to the ``potential'' which appears in the Hamiltonian of vacuum
Bianchi IX spacetimes, our result means that the spacetimes do not become
Mixmaster necessarily.

</DOC>
<DOC>
<DOCNO> 150346 </DOCNO>
D0-D4 system and QCD_{3+1}


  We consider a $(3+1)$-dimensional QCD model using a dual supergravity
description with a non-extremal $D0$-$D4$ brane background. We calculate the
spectrum of glueball masses and Wilson loops in the background. The mass
spectrum is shown to coincide with one in non-extremal $D4$-brane systems, and
an area low of spatial Wilson loops is established. We show that there is a
region that Kaluza-Klein modes of the Euclidean time direction are decoupled
without decoupling glueball masses.

</DOC>
<DOC>
<DOCNO> 170770 </DOCNO>
Proposal of an experimental scheme for realising a translucent


  Purpose of this paper is to suggest a scheme, which can be realised with
today's technology and could be used for entangling a probe to a photon qubit
based on polarisation. Using this probe a translucent or a coherent
eavesdropping can be performed.

</DOC>
<DOC>
<DOCNO> 99501 </DOCNO>
On [L]-homotopy groups


  Some properties of [L]-homotopy group for finite complex L are investigated.
It is proved that for complex L whose extension type lying between Sn and Sn+1
n-th [L]-homotopy group of Sn is isomorphic to Z.

</DOC>
<DOC>
<DOCNO> 11795 </DOCNO>
Fluctuation-Driven 1st-Order Isotropic-to-Tetrahedratic Phase Transition


  Motivated in part by recent experiments on liquid crystals with bent-core
molecules, which are observed to display a spontaneous chiral symmetry
breaking, we introduce a field theory of a 3rd-rank tensor order parameter
T^{ijk} to describe the isotropic-to-tetrahedratic phase transition that we
predict to take place in these materials. We study the critical properties of
the corresponding phase transition and find that this transition, continuous at
the mean-field level, is generically driven 1st-order by thermal fluctuations.

</DOC>
<DOC>
<DOCNO> 118929 </DOCNO>
The distance to the nearest star-forming clouds: MBM12 and MBM20


  We present high-resolution spectra (R ~ 49,000) of stars that have parallax
measurements from the Hipparcos satellite and are projected along the line of
sight to the two nearest known star forming clouds to the Sun: MBM12 and MBM20.
The spectra were obtained with the FOCES Echelle Spectrograph at the 2.2 meter
telescope in Calar Alto, Spain and the wavelength range was chosen to include
the interstellar NaI D lines at 5889.950 Angstroms and 5895.924 Angstroms.
Since the stars are at a range of distances, we use their spectra along with
their parallaxes from Hipparcos to determine the distance to the molecular gas.
The stars in front of the cloud do not show interstellar NaI D absorption
features while the stars behind the cloud do show interstellar absorption
features. We find that both clouds are somewhat more distant than previously
estimated. The revised distance to MBM12 is 58+-5 pc < d < 90+-12 pc and the
distance to MBM20 is 112+-15 pc < d < 161+-21 pc.

</DOC>
<DOC>
<DOCNO> 169804 </DOCNO>
The f-conditioned Phase Transform


  We present a quantum algorithm for the f-conditioned phase transform which
does not require any initialization of ancillary register. We also develop a
quantum algorithm that can solve the generalized Deutsch-Jozsa problem by a
single evaluation of a function.

</DOC>
<DOC>
<DOCNO> 119158 </DOCNO>
Formation of the Galactic stellar halo. Origin of the


  Motivated by the recently improved knowledge on the kinematic and chemical
properties of the Galactic metal-poor stars, we present the numerical
simulation for the formation of the Galactic stellar halo to interpret the
observational results. As a model for the Galaxy contraction, we adopt the
currently standard theory of galaxy formation based on the hierarchical
assembly of the cold dark matter fluctuations. We find, for the simulated stars
with [Fe/H]$\le-1.0$, that there is no strong correlation between metal
abundances and orbital eccentricities, in good agreement with the observations.
Moreover, the observed fraction of the low eccentricity stars is reproduced
correctly for [Fe/H]$\le-1.6$ and approximately for the intermediate abundance
range of $-1.6<$[Fe/H]$\le-1.0$. We show that this successful reproduction of
the kinematics of the Galactic halo is a natural consequence of the
hierarchical evolution of the subgalactic clumps seeded from the cold dark
matter density fluctuations.

</DOC>
<DOC>
<DOCNO> 100921 </DOCNO>
$\Uh$ invariant Quantization of Coadjoint Orbits and Vector Bundles over


  Let M be a coadjoint semisimple orbit of a simple Lie group G. Let $U_h(\g)$
be a quantum group corresponding to G. We construct a universal family of
$U_h(\g)$ invariant quantizations of the sheaf of functions on M and describe
all such quantizations. We also describe all two parameter $U_h(\g)$ invariant
quantizations on M, which can be considered as $U_h(\g)$ invariant
quantizations of the Kirillov-Kostant-Souriau (KKS) Poisson bracket on M. We
also consider how those quantizations relate to the natural polarizations of M
with respect to the KKS bracket. Using polarizations, we quantize the sheaves
of sections of vector bundles on M as one- and two-sided $U_h(\g)$ invariant
modules over a quantized function sheaf.

</DOC>
<DOC>
<DOCNO> 100165 </DOCNO>
On the valuation of Paris options: foundational results


  This paper adresses the valuation of the Paris barrier options proposed by
Yor, Jeanblanc-Picque, and Chesnay (Advances in Applied Probability, 29(1997),
165-184) using the Laplace transform approach. Based on suggestions by Pliska
the notion of Paris options is extended such that their valuation is possible
at any point during their lifespan. The Laplace transforms derived by Yor et
al. are modified when necessary, and their basic analytic properties are
discussed.

</DOC>
<DOC>
<DOCNO> 178796 </DOCNO>
Classification of the Nuclear Multifragmentation Phase Transition


  Using a recently proposed classification scheme for phase transitions in
finite systems [Phys.Rev.Lett.{\bf 84},3511 (2000)] we show that within the
statistical standard model of nuclear multifragmentation the predicted phase
transition is of first order.

</DOC>
<DOC>
<DOCNO> 9454 </DOCNO>
Physics of Fashion Fluctuations


  We consider a market where many agents trade many different types of products
with each other. We model development of collective modes in this market, and
quantify these by fluctuations that scale with time with a Hurst exponent of
about 0.7. We demonstrate that individual products in the model occationally
become globally accepted means of exchange, and simultaneously become very
actively traded. Thus collective features similar to money spontaneously
emerge, without any a priori reason.

</DOC>
<DOC>
<DOCNO> 13175 </DOCNO>
Transverse thermal depinning and nonlinear sliding friction of an


  We study the response of an adsorbed monolayer under a driving force as a
model of sliding friction phenomena between two crystalline surfaces with a
boundary lubrication layer. Using Langevin-dynamics simulation, we determine
the nonlinear response in the direction transverse to a high symmetry direction
along which the layer is already sliding. We find that below a finite
transition temperature, there exist a critical depinning force and hysteresis
effects in the transverse response in the dynamical state when the adlayer is
sliding smoothly along the longitudinal direction.

</DOC>
<DOC>
<DOCNO> 122795 </DOCNO>
Tree structure of the percolating Universe


  We present a numerical study of topological descriptors of initially Gaussian
and scale-free density perturbations evolving via gravitational instability in
an expanding universe. We carefully evaluate and avoid numerical contamination
in making accurate measurements on simulated fields on a grid in a finite box.
Independent of extent of non linearity, the measured Euler number of the
excursion set at the percolation threshold, $\delta_c$, is positive and nearly
equal to the number of isolated components, suggesting that these structures
are trees. Our study of critical point counts reconciles the clumpy appearance
of the density field at $\delta_c$ with measured filamentary local curvature.
In the Gaussian limit, we measure $|\delta_c|> \sigma$ in contrast to widely
held belief that $|\delta_c| \sim \sigma$, where $\sigma^2$ is the variance of
the density field.

</DOC>
<DOC>
<DOCNO> 8789 </DOCNO>
X-ray Anomalous Scattering Study of a Charge-Ordered State in NaV2O5


  Charge ordering of V4+ and V5+ in NaV2O5 has been studied by an X-ray
diffraction technique using anomalous scattering near a vanadium K-absorption
edge to critically enhance a contrast between the two ions. A dramatic energy
dependence of the superlattice intensities is observed below Tc=35 K.
Consequently, the charge ordering pattern is the zigzag-type ladders with the
unit cell 2a*2b*4c, but not the chain-type originally proposed for the
spin-Peierls state. Charge disproportionation suggested in our model as the
average valence V^{4.5+-delta_c/2} is observed below T_C, showing continuous
variation of delta_c as a function of temperature.

</DOC>
<DOC>
<DOCNO> 170322 </DOCNO>
The histories interpretation: stability instead of consistency?


  Using a reformulation of conventional results in decoherence theory, a
condition is proposed for singling out a distinguished class of histories which
includes those which use the ``pointer basis'' of Zurek.

</DOC>
<DOC>
<DOCNO> 10365 </DOCNO>
Nonperiodic Flux to Voltage Conversion of an Arithmetic Series Array of


  A theoretical study on the voltage response function <V> of a series array of
dc SQUIDs is presented in which the elementary dc SQUID loops vary in size and,
possibly, in orientation. Such series arrays of two-junction SQUIDs possess
voltage response functions vs. external magnetic field B that differ
substantially from those of corresponding regular series arrays with identical
loop-areas, while maintaining a large voltage swing as well as a low noise
level. Applications include the design of current amplifiers and quantum
interference filters.

</DOC>
<DOC>
<DOCNO> 101645 </DOCNO>
Symplectic geometry on moduli spaces of holomorphic bundles over complex


  We give a comparative description of the Poisson structures on the moduli
spaces of flat connections on real surfaces and holomorphic Poisson structures
on the moduli spaces of holomorphic bundles on complex surfaces. The symplectic
leaves of the latter are classified by restrictions of the bundles to certain
divisors. This can be regarded as fixing a "complex analogue of the holonomy"
of a connection along a "complex analogue of the boundary" in analogy with the
real case.

</DOC>
<DOC>
<DOCNO> 69453 </DOCNO>
Vibrating the QCD string


  The large distance behaviour of the adiabatic hybrid potentials is studied in
the framework of the QCD string model. The calculated spectra are shown to be
the result of interplay between potential-type longitudinal and string-type
transverse vibrations.

</DOC>
<DOC>
<DOCNO> 71899 </DOCNO>
The Vacuum Polarization: Power Corrections beyond OPE ?


  We compute the vacuum polarization on the lattice using non-perturbatively
O(a) improved Wilson fermions. The result is compared with the operator product
expansion (OPE).

</DOC>
<DOC>
<DOCNO> 67964 </DOCNO>
On the numerical analysis of triplet pair production cross-sections and


  The double and single differential cross-sections with respect to positron
and electron energies as well as the total cross-section of triplet production
in the laboratory frame are calculated numerically in order to develop a Monte
Carlo code for modelling electron-photon cascades in a soft photon field. To
avoid numerical integration irregularities of the integrands, which are
inherent to problems of this type, we have used suitable substitutions in
combination with a modern powerful program code Mathematica allowing one to
achieve reliable higher-precission results. The results obtained for the total
cross-section closely agree with others estimated analytically or by a
different numerical approach. The results for the double and single
differential cross-sections turn out to be somewhat different from some
reported recently. The mean energy of the produced particles, as a function of
the characteristic collisional parameter (the electron rest frame photon
energy), is calculated and approximated by an analytical expression that
revises other known approximations over a wide range of values of the argument.
The primary-electron energy loss rate due to triplet pair production is shown
to prevail over the inverse Compton scattering loss rate at several ($\sim$2)
orders of magnitude higher interaction energy than that predicted formerly.

</DOC>
<DOC>
<DOCNO> 11309 </DOCNO>
Comment on "First Observation for a Cuprate Superconductor of


  The aim of the present comment is to provoke the performance of simple
additional measurements at Tc which, after a professional experimental data
processing, will reveal an important quantitative information concerning the GL
parameters and applicability of the GL theory for high-Tc superconductors in
general. Confirmation of this would be crucial for the further studies of the
fluctuation phenomena in superconductors.

</DOC>
<DOC>
<DOCNO> 152016 </DOCNO>
Superstring Vertex Operators in an AdS_5 x S^5 Background


  A quantizable action has recently been proposed for the superstring in an
AdS_5 x S^5 background with Ramond-Ramond flux. In this paper, we construct
physical vertex operators corresponding to on-shell fluctuations around the
AdS_5 x S^5 background. The structure of these AdS_5 x S^5 vertex operators
closely resembles the structure of the massless vertex operators in a flat
background.

</DOC>
<DOC>
<DOCNO> 116340 </DOCNO>
Dielectronic recombination of lithium-like Ni25+ ions - high resolution


  Absolute dielectronic recombination (DR) rates for lithium-like
Ni$^{25+}$($1s^2 2s$) ions were measured at high-energy resolution at the
Heidelberg heavy-ion storage ring TSR. We studied the center-of-mass energy
range 0--130 eV which covers all $\Delta n$=0 core excitations. The influence
of external crossed electric (0--300 V/cm) and magnetic (41.8--80.1 mT) fields
was investigated. For the measurement at near-zero electric field resonance
energies and strengths are given for Rydberg levels up to n$=$32; also
Maxwellian plasma rate coefficients for the $\Delta n$=0 DR at electron
temperatures between 0.5 and 200 eV are provided. For increasing electric field
strength we find that for both the $2p_{1/2}$ and the $2p_{3/2}$ series of
Ni$^{24+}$($1s^2 2p_j n\ell$) Rydberg resonances with n>30 the DR rate
coefficient increases approximately linearly by up to a factor of 1.5. The
relative increase due to the applied electric field for Ni$^{25+}$ is
remarkably lower than that found in previous measurements with lighter
isoelectronic Si$^{11+}$, Cl$^{14+}$ and also Ti$^{19+}$ ions, [T. Bartsch et
al, Phys. Rev. Lett. {\bf 79}, 2233 (1997); {\bf 82}, 3779 (1999) and to be
published] and in contrast to the results for lighter ions no clear dependence
of the electric field enhancement on the magnetic field strength is found. The
Maxwellian plasma rate coefficients for $\Delta n$=0 DR of Ni$^{25+}$ are
enhanced by at most 11% in the presence of the strongest experimentally applied
fields.

</DOC>
<DOC>
<DOCNO> 169803 </DOCNO>
Subnormal operators regarded as generalized observables and


  In this paper, subnormal operators, not necessarily bounded, are discussed as
generalized observables. In order to describe not only the information about
the probability distribution of the output data of their measurement but also a
framework of their implementations, we introduce a new concept
compound-system-type normal extension, and we derive the compound-system-type
normal extension of a subnormal operator, which is defined from an irreducible
unitary representation of the algebra su(1,1). The squeezed states are
characterized as the eigenvectors of an operator from this viewpoint, and the
squeezed states in multi-particle systems are shown to be the eigenvectors of
the adjoints of these subnormal operators under a representation. The affine
coherent states are discussed in the same context, as well.

</DOC>
<DOC>
<DOCNO> 118432 </DOCNO>
A correlation between the SiO and the Fe 6.4 keV line emission from the


  In this letter we present a map of the GC in the 1-0 line of SiO covering the
same region than the ASCA observations of the Fe 6.4 keV line. The SiO emission
is restricted to molecular clouds with radial velocity between 10 and 60 km/s
in the Sgr A and Sgr B complexes. We find a correlation between the SiO
morphology and the spatial distribution of the Fe 6.4 keV line, on the large
scale and also within Sgr A and Sgr B. The SiO abundance increases by a factor
of 20 in the regions with strong Fe 6.4 keV line. This indicates that the Fe
6.4 keV line mainly arises from molecular clouds with large gas phase abundance
of refractory elements. We discuss the implications of the correlation on the
origin of the hard X-rays, and the heating and the chemistry of the molecular
clouds in the GC

</DOC>
<DOC>
<DOCNO> 13781 </DOCNO>
Influence of nano-mechanical properties on single electron tunneling: A


  We describe single electron tunneling through molecular structures under the
influence of nano-mechanical excitations. We develop a full quantum mechanical
model, which includes charging effects and dissipation, and apply it to the
vibrating C$_{60}$ single electron transistor experiment by Park {\em et al.}
{[Nature {\bf 407}, 57 (2000)].} We find good agreement and argue vibrations to
be essential to molecular electronic systems. We propose a mechanism to realize
negative differential conductance using local bosonic excitations.

</DOC>
<DOC>
<DOCNO> 8872 </DOCNO>
One-Dimensional Textures and Critical Velocity in Superfluid 3He-A


  We study theoretically the stability of flow in superfluid 3He-A. The
calculations are done using a one-dimensional model where the order parameter
depends only on the coordinate in the direction of the superfluid velocity v_s.
We concentrate on the case that the external magnetic field H is perpendicular
to v_s, where only few results are available analytically. We calculate the
critical velocity v_c at which the superflow becomes unstable against the
formation of continuous vortices. The detailed dependence of v_c on the
temperature and on the form of the underlying orbital texture l(r) is
investigated. Both uniform and helical textures and two types of domain-wall
structures are studied. The results are partially in agreement with experiments
made in a rotating cylinder.

</DOC>
<DOC>
<DOCNO> 8394 </DOCNO>
Dielectric response of charge induced correlated state in the


  Conductivity and permittivity of the quasi-one-dimensionsional organic
transfer salt (TMTTF)2PF6 have been measured at low frequencies (10^3-10^7 Hz)
between room temperature down to below the temperature of transition into the
spin-Peierls state. We interpret the huge real part of the dielectric
permittivity (up to 10^6) in the localized state as the realization in this
compound of a charge ordered state of Wigner crystal type due to long range
Coulomb interaction.

</DOC>
<DOC>
<DOCNO> 117840 </DOCNO>
Chandra Observations of the Crab-like Supernova Remnant G21.5-0.9


  Chandra observations of the Crab-like supernova remnant G21.5-0.9 reveal a
compact central core and spectral variations indicative of synchrotron burn-off
of higher energy electrons in the inner nebula. The central core is slightly
extended, perhaps indicating the presence of an inner wind-shock nebula
surrounding the pulsar. No pulsations are observed from the central region,
yielding an upper limit of ~40% for the pulsed fraction. A faint outer shell
may be the first evidence of the expanding ejecta and blast wave formed in the
initial explosion, indicating a composite nature for G21.5-0.9.

</DOC>
<DOC>
<DOCNO> 68478 </DOCNO>
Effective Lagrangians in bound state calculations


  In order to investigate specific aspects of bound state calculations in a
non-relativistic framework, we consider the energy-levels of a massive scalar
particle, which moves in an external field and interacts in addition with a
massless scalar particle. The discussion includes the following topics:
dimensionally regularized bound-state calculations, ultraviolet finiteness of
bound-state observables and their independence of the off-mass-shell behavior
of Green functions, non-renormalizable interactions, structure of the
non-relativistic two-point function, power counting and matching.

</DOC>
<DOC>
<DOCNO> 118165 </DOCNO>
X-Ray Spectral and Timing Evolution During the Decay of the 1998


  We report on the X-ray spectral and timing behavior of the recurrent X-ray
transient 4U 1630-47 for 51 RXTE observations made during the decay of its 1998
outburst. The observations began when the source was still relatively bright,
and, during one of the early observations, a QPO with a non-Lorentzian profile
occurred near 6 Hz. As the source decayed, the X-ray flux dropped exponentially
with an e-folding time of 14.4 d. The exponential decay was interrupted by an
increase in the X-ray flux, and a secondary maximum occurred 89 d after the
onset of the outburst. A transition marked by significant changes in the timing
and spectral properties of the source occurred 104 d after the start of the
outburst. The transition is similar to soft-to-hard state transitions observed
in other black hole candidate X-ray binaries. Most of the changes associated
with the transition occurred in less than 2 d. The timing changes include an
increase in the continuum noise level from less than 4% RMS to greater than 10%
RMS and the appearance of a quasi-periodic oscillation (QPO) at 3.4 Hz with an
RMS amplitude of 7.3% in the 2-21 keV energy band. At the transition, the
energy spectrum also changed with an abrupt drop in the soft component flux in
the RXTE band pass. A change in the power-law photon index from 2.3 to 1.8,
also associated with the transition, occurred over a time period of 8 d. After
the transition, the source flux continued to decrease, and the QPO frequency
decayed gradually from 3.4 Hz to about 0.2 Hz.

</DOC>
<DOC>
<DOCNO> 178889 </DOCNO>
Few-body resonances in light nuclei


  We have localized several few-body resonances in light nuclei, using methods
which can properly handle two- or three-body resonant states. Among other
results, we predict the existence of a three-neutron resonance, small
spin-orbit splittings between the low-lying states in He-5 and Li-5, the
nonexistence of the soft dipole resonance in He-6, new 1+ states in Li-8 and
B-8, and the presence of a nonlinear amplification phenomenon in the 0+_2 state
of C-12.

</DOC>
<DOC>
<DOCNO> 99397 </DOCNO>
Homogeneous Hypersurfaces with Isotropy in Affine Four-space


  We classify the non-degenerate homogeneous hypersurfaces in real and complex
affine four-space whose symmetry group is at least four-dimensional.

</DOC>
<DOC>
<DOCNO> 67842 </DOCNO>
Bremsstrahlung from an Equilibrating Quark-Gluon Plasma


  The photon production rate from a chemically equilibrating quark-gluon plasma
likely to be produced at RHIC (BNL) and LHC (CERN) energies is estimated taking
into account bremsstrahlung. The plasma is assumed to be in local thermal
equilibrium, but with a phase space distribution that deviates from the Fermi
or Bose distribution by space-time dependent factors (fugacities). The photon
spectrum is obtained by integrating the photon rate over the space-time history
of the plasma, adopting a boost invariant cylindrically symmetric transverse
expansion of the system with different nuclear profile functions. Initial
conditions obtained from a self-screened parton cascade calculation and, for
comparison, from the HIJING model are used. Compared to an equilibrated plasma
at the same initial energy density, taken from the self-screened parton
cascade, a moderate suppression of the photon yield by a factor of one to five
depending on the collision energy and the photon momentum is observed. The
individual contributions to the photon production, however, are completely
different in the both scenarios.

</DOC>
<DOC>
<DOCNO> 85077 </DOCNO>
Gravitational Radiation Theory and Light Propagation


  The paper gives an introduction to the gravitational radiation theory of
isolated sources and to the propagation properties of light rays in radiative
gravitational fields. It presents a theoretical study of the generation,
propagation, back-reaction, and detection of gravitational waves from
astrophysical sources. After reviewing the various quadrupole-moment laws for
gravitational radiation in the Newtonian approximation, we show how to
incorporate post-Newtonian corrections into the source multipole moments, the
radiative multipole moments at infinity, and the back-reaction potentials. We
further treat the light propagation in the linearized gravitational field
outside a gravitational wave emitting source. The effects of time delay,
bending of light, and moving source frequency shift are presented in terms of
the gravitational lens potential. Time delay results are applied in the
description of the procedure of the detection of gravitational waves.

</DOC>
<DOC>
<DOCNO> 151507 </DOCNO>
Quantum gauge symmetry from finite field dependent BRST transformations


  Using the technique of finite field dependent BRST transformations we show
that the classical massive Yang-Mills theory and the pure Yang-Mills theory
whose gauge symmetry is broken by a gauge fixing term are identical from the
view point of quantum gauge symmetry. The explicit infinitesimal
transformations which leave the massive Yang-Mills theory BRST invariant are
given.

</DOC>
<DOC>
<DOCNO> 84727 </DOCNO>
Diffusion of the electromagnetic energy due to the backscattering off


  Electromagnetic waves propagate in the Schwarzschild spacetime like in a
nonuniform medium with a varying refraction index. A fraction of the radiation
scatters off the curvature of the geometry. The energy of the backscattered
part of an initially outgoing pulse of electromagnetic radiation can be
estimated, in the case of dipole radiation, by a compact formula depending on
the initial energy, the Schwarzschild radius and the pulse location. The
magnitude of the backscattered energy depends on the frequency spectrum of the
initial configuration. This effect becomes negligible in the short wave limit,
but it can be significant in the long wave regime. Similar results hold for the
massless scalar fields and are expected to hold also for weak gravitational
waves.

</DOC>
<DOC>
<DOCNO> 122541 </DOCNO>
Primordial Isocurvature Perturbations: Testing the Adiabaticity of the


  Prospects for testing the adiabaticity of the primordial cosmological
perturbations using MAP and PLANCK are evaluated. The most general cosmological
perturbation in a universe with just baryons, photons, neutrinos, and a cold
dark matter (CDM) component is described. In addition to the familiar adiabatic
mode, there are four nonsingular isocurvature modes: a baryon isocurvature
mode, a CDM isocurvature mode, a neutrino density isocurvature mode, and a
neutrino velocity isocurvature mode. The most general perturbation is described
by a 5x5, positive-definite, symmetric, matrix-valued function of wave number
whose off-diagonal elements represent the correlations between the above
mentioned modes. We found that when three modes and their correlations are
admitted, the fractional uncertainties in the cosmological parameters and
amplitudes of the isocurvature modes and their correlations become of order
unity. These degeneracies, however, can be broken with the polarization
information provided by PLANCK, reducing the uncertainties to below the ten
percent level. Polarization is thus crucial to testing the adiabaticity of the
primordial fluctuations.

</DOC>
<DOC>
<DOCNO> 80575 </DOCNO>
Adjoint "quarks" on coarse anisotropic lattices: Implications for string


  A detailed study is made of four dimensional SU(2) gauge theory with static
adjoint ``quarks'' in the context of string breaking. A tadpole-improved action
is used to do simulations on lattices with coarse spatial spacings $a_s$,
allowing the static potential to be probed at large separations at a
dramatically reduced computational cost. Highly anisotropic lattices are used,
with fine temporal spacings $a_t$, in order to assess the behavior of the
time-dependent effective potentials. The lattice spacings are determined from
the potentials for quarks in the fundamental representation. Simulations of the
Wilson loop in the adjoint representation are done, and the energies of
magnetic and electric ``gluelumps'' (adjoint quark-gluon bound states) are
calculated, which set the energy scale for string breaking. Correlators of
gauge-fixed static quark propagators, without a connecting string of spatial
links, are analyzed. Correlation functions of gluelump pairs are also
considered; similar correlators have recently been proposed for observing
string breaking in full QCD and other models. A thorough discussion of the
relevance of Wilson loops over other operators for studies of string breaking
is presented, using the simulation results presented here to support a number
of new arguments.

</DOC>
<DOC>
<DOCNO> 118592 </DOCNO>
The evolution of the stellar populations in low surface brightness


  We investigate the star formation history and chemical evolution of low
surface brightness (LSB) disk galaxies by modelling their observed
spectro-photometric and chemical properties using a galactic chemical and
photometric evolution model incorporating a detailed metallicity depen dent set
of stellar input data. For a large fraction of the LSB galaxies in our sample,
observed properties are best explained by models incorporating an exponentially
decreasing global star formation rate (SFR) ending at a present-day gas
fraction (M_{gas}/(M_{gas}+M_{stars}) = 0.5 for a galaxy age of 14 Gyr. For
some galaxies small amplitude star formation bursts are required to explain the
contribution of the young (5-50 Myr old) stellar population to the galaxy
integrated luminosity. This suggests that star formation has proceeded in a
stochastic manner.
  The presence of an old stellar population in many late-type LSB galaxies
suggests that LSB galaxies roughly follow the same evolutionary history as HSB
galaxies, except at a much lower rate. In particular, our results imply that
LSB galaxies do not form late, nor have a delayed onset of star formation, but
simply evolve slowly.

</DOC>
<DOC>
<DOCNO> 11844 </DOCNO>
Unexpected behavior in 3He films and the theory of fermions in two


  It is shown that the recently observed and unexplained behavior for the spin
diffusion in 3He films can be understood in terms of the Fermi liquid theory,
provided nonperturbative effects characteristic of the two dimensions are taken
into account. It is conjectured that such a behavior suggests the onset of a
regime in which spin-current is conserved.

</DOC>
<DOC>
<DOCNO> 151169 </DOCNO>
Dirichlet Branes on a Calabi-Yau Three-fold Orbifold


  The D-brane spectrum of a $\Zop_2\times\Zop_2$ Calabi-Yau three-fold orbifold
of toroidally compactified Type IIA and Type IIB string theory is analysed
systematically. The corresponding K-theory groups are determined and complete
agreement is found. New kinds of stable non-BPS D-branes are found, whose
stability regions are far more complicated than the previously discussed
non-BPS D-branes. The decay channels of non-BPS D-branes beyond their stability
regions are identified. Finally the T-dual orbifold is analysed and a suitable
K-theory is found.

</DOC>
<DOC>
<DOCNO> 84237 </DOCNO>
Lanczos potentials and curvature-free connections aligned to a geodesic


  By the method of rho-integration we obtain all Lanczos potentials L_{ABCA'}
of the Weyl spinor that, in a certain sense, are aligned to a geodesic
shear-free expanding null congruence. We also obtain all spinors
H_{ABA'B'}=Q_{AB}o_{A'}o_{B'}, Q_{AB}=Q_{(AB)} satisfying
nabla_{(A}{}^{B'}H_{BC)A'B'}=L_{ABCA'}. We go on to prove that H_{ABA'B'} can
be chosen so that Gamma_{ABCA'}=nabla_{(A}{}^{B'} H_{B)CA'B'} defines a metric
asymmetric curvature-free connection such that L_{ABCA'}=Gamma_{(ABC)A'} is a
Lanczos potential that is aligned to the geodesic shear-free expanding
congruence. These results are a generalization to a large class of
algebraically special spacetimes (including all vacuum ones for which the
principal null direction is expanding) of the curvature-free connection of the
Kerr spacetime found by Bergqvist and Ludvigsen, which was used in a
construction of quasi-local momentum.

</DOC>
<DOC>
<DOCNO> 150752 </DOCNO>
On relevant boundary perturbations of unitary minimal models


  We consider unitary Virasoro minimal models on the disk with Cardy boundary
conditions and discuss deformations by certain relevant boundary operators,
analogous to tachyon condensation in string theory. Concentrating on the least
relevant boundary field, we can perform a perturbative analysis of
renormalization group fixed points. We find that the systems always flow
towards stable fixed points which admit no further (non-trivial) relevant
perturbations. The new conformal boundary conditions are in general given by
superpositions of 'pure' Cardy boundary conditions.

</DOC>
<DOC>
<DOCNO> 120921 </DOCNO>
Distance Constraints for High Velocity Clouds from Optical Emission


  We report results from a survey of high velocity clouds and the Magellanic
Stream for faint, diffuse optical recombination emission lines. We detect
H-alpha emission with surface brightness from 41 to 1680 milli-Rayleighs (mR)
from HVCs, and from <40 to 1360 mR in the MS. A simple model for the
photoionizing radiation emergent from the Galaxy, normalized to the HVCs A and
M with known distances, predicts distances from a few to 40 kpc, placing the
faintest HVCs in the Galactic halo, too far away for a Galactic fountain. This
model cannot explain the bright and spatially varying H-alpha in the Magellanic
Stream, which requires another source of ionization. However, we do not find
any HVCs super-faint in H-alpha; even with another ionization source, we
conclude that the detected HVCs are not more than 2--4 times the distance of
the MS (100-200 kpc).

</DOC>
<DOC>
<DOCNO> 170773 </DOCNO>
Dynamical Stability of an Ion in a Linear Trap as a Solid-State Problem


  When an ion confined in a linear ion trap interacts with a coherent laser
field, the internal degrees of freedom, related to the electron transitions,
couple to the vibrational degree of freedom of the ion. As a result of this
interaction, quantum dynamics of the vibrational degree of freedom becomes
complicated, and in some ranges of parameters even chaotic. We analyze the
vibrational ion dynamics using a formal analogy with the solid-state problem of
electron localization. In particular, we show how the resonant approximation
used in analysis of the ion dynamics, leads to a transition from a
two-dimensional (2D) to a one-dimensional problem (1D) of electron
localization. The localization length in the solid-state problem is estimated
in cases of weak and strong interaction between the cites of the 2D cell by
using the methods of resonance perturbation theory, common in analysis of 1D
time-dependent dynamical systems.

</DOC>
<DOC>
<DOCNO> 69849 </DOCNO>
Wandzura-Wilczek approximation for the twist-3 DVCS amplitude


  We present a derivation of Wandzura-Wilczek (WW) like relations for skewed
parton distributions. It is demonstrated for photon-pion scattering that the
skewed twist-3 parton distributions contributing to the DVCS amplitude have
discontinuities at the points $x=\pm\xi$ in the WW approximation. This may lead
to a violation of factorisation for the twist-3 DVCS amplitude with transverse
polarization of the virtual photon. We show, however, that the contribution of
the divergencies to the scattering of a transversely polarized virtual photon
affects DVCS observables only at order $1/Q^2$ and can be neglected at twist-3
accuracy. For the scattering of a longitudinally polarized photon the twist-3
amplitude is free of such divergencies.

</DOC>
<DOC>
<DOCNO> 99500 </DOCNO>
Path-wise solutions of SDE's driven by Levy processes


  In this paper we show that a path-wise solution to the following integral
equation $$ Y_t = \int_0^t f(Y_t) dX_t \qquad Y_0=a \in \R^d $$ exists under
the assumption that X_t is a L\'evy process of finite p-variation for some $p
\geq1$ and that f is an $\alpha$-Lipschitz function for some alpha>p. There are
two types of solution, determined by the solution's behaviour at jump times of
the process X, one we call geometric the other forward. The geometric solution
is obtained by adding fictitious time and solving an associated integral
equation. The forward solution is derived from the geometric solution by
correcting the solution's jump behaviour. L\'evy processes, generally, have
unbounded variation. So we must use a pathwise integral different from the
Lebesgue-Stieltjes integral. When X has finite p-variation almost surely for
p<2 we use Young's integral. This is defined whenever f and g have finite p and
q-variation for 1/p+1/q>1 (and they have no common discontinuities). When p>2
we use the integral of Lyons. In order to use this integral we construct the
L\'evy area of the L\'evy process and show that it has finite (p/2)-variation
almost surely.

</DOC>
<DOC>
<DOCNO> 116398 </DOCNO>
Photoionization and Recombination


  Theoretically self-consistent calculations for photoionization and (e + ion)
recombination are described. An identical eigenfunction expansion for the ion
is employed in coupled channel calculations for both processes, thus ensuring
consistently accurate cross sections and rates in an ab initio manner. The
theoretical treatment of (e + ion) recombination subsumes both the non-resonant
recombination ('radiative recombination'), and the resonant recombination
('di-electronic recombination') processes in a unified scheme. In addition to
the total, unified recombination rates, level-specific recombination rates and
photoionization cross sections are obtained for a large number of atomic
levels. Both relativistic Breit-Pauli, and non-relativistic LS coupling,
calculations are carried out in the close coupling approximation using the
R-matrix method. Although the calculations are computationally intensive, they
yield nearly all photoionization and recombination parameters needed for
astrophysical photoionization models with higher precision than hitherto
possible, estimated at about 10-20 % from comparison with experimentally
available data (including 'experimentally derived DR rates'). Results are
electronically available for over 40 atoms and ions. Photoionization and
recombination of He-, and Li-like C and Fe are described for X-ray modeling.
The unified method yields total and complete (e+ion) recombination rate
coeffcients, that can not otherwise be obtained theoretically or
experimentally. "temp" 23 lines, 1524 characters

</DOC>
<DOC>
<DOCNO> 69542 </DOCNO>
Estimating sigma-meson couplings from D \to 3\pi decays


  Using recent experimental evidence from E791 on the sigma meson in D \to 3\pi
decays, we study the relevant couplings in D \to \sigma \pi and \sigma \to \pi\
pi within the accepted theoretical framework for non leptonic D decays. We also
review the linear sigma model, finding that it gives a description which is
consistent with the experimental data.

</DOC>
<DOC>
<DOCNO> 152552 </DOCNO>
Generalized WDVV equations for F4 pure N=2 Super-Yang-Mills theory


  An associative algebra of holomorphic differential forms is constructed
associated with pure N=2 Super-Yang-Mills theory for the Lie algebra F4.
Existence and associativity of this algebra, combined with the general
arguments in the work of Marshakov, Mironov and Morozov, proves that the
prepotential of this theory satisfies the generalized WDVV system.

</DOC>
<DOC>
<DOCNO> 13833 </DOCNO>
Analysis of the computational complexity of solving random


  The computational complexity of solving random 3-Satisfiability (3-SAT)
problems is investigated. 3-SAT is a representative example of hard
computational tasks; it consists in knowing whether a set of alpha N randomly
drawn logical constraints involving N Boolean variables can be satisfied
altogether or not. Widely used solving procedures, as the
Davis-Putnam-Loveland-Logeman (DPLL) algorithm, perform a systematic search for
a solution, through a sequence of trials and errors represented by a search
tree. In the present study, we identify, using theory and numerical
experiments, easy (size of the search tree scaling polynomially with N) and
hard (exponential scaling) regimes as a function of the ratio alpha of
constraints per variable. The typical complexity is explicitly calculated in
the different regimes, in very good agreement with numerical simulations. Our
theoretical approach is based on the analysis of the growth of the branches in
the search tree under the operation of DPLL. On each branch, the initial 3-SAT
problem is dynamically turned into a more generic 2+p-SAT problem, where p and
1-p are the fractions of constraints involving three and two variables
respectively. The growth of each branch is monitored by the dynamical evolution
of alpha and p and is represented by a trajectory in the static phase diagram
of the random 2+p-SAT problem. Depending on whether or not the trajectories
cross the boundary between phases, single branches or full trees are generated
by DPLL, resulting in easy or hard resolutions.

</DOC>
<DOC>
<DOCNO> 12713 </DOCNO>
Effects of confinement on self-assembling systems


  Systems in which particles can self-assemble into mono- or bilayers can form
variety of stable and metastable structures on a nanometer length scale. For
this reason confinement has a particularly strong effect on such systems. We
discuss in some detail effects of confinement on lamellar and cubic phases with
double-diamond structure. Structural deformations in slit geometry are
described for large and small unit cells of the structure (in units of the
thickness of the monolayer) and for various strengths of interactions with the
confining surfaces. We show how the structural changes of the confined fluid
are reflected in the measurable solvation force between the confining walls.

</DOC>
<DOC>
<DOCNO> 118077 </DOCNO>
Distances to Cepheid Open Clusters Via Optical and K-Band Imaging


  We investigate the reddening and Main Sequence fitted distances to eleven
young, Galactic open clusters that contain Cepheids. Each cluster contains or
is associated with at least one Cepheid variable star. Reddening to the
clusters is estimated using the U-B:B-V colours of the OB stars and the
distance modulus to the cluster is estimated via B-V:V and V-K:V
colour-magnitude diagrams. By main-sequence fitting we proceed to calibrate the
Cepheid P-L relation and find M_V=-2.81xlogP-1.33 +/-0.32 and
M_K=-3.44xlogP-2.20 +/-0.29 and a distance modulus to the LMC of 18.55+/-0.32
in the V-band and 18.47+/-0.29 in the K-band giving an overall distance modulus
to the LMC of 18.51+/-0.3.
  In the case of two important clusters we find that the U-B:B-V diagram in
these clusters is not well fitted by the standard Main Sequence line. In one
case, NGC7790, we find that the F stars show a UV excess which if caused by
metallicity would imply Fe/H ~ -1.5; this is anomalously low compared to what
is expected for young open clusters. In a second case, NGC6664, the U-B:B-V
diagram shows too red U-B colours for the F stars which in this case would
imply a higher than solar metallicity. If these effects are due to metallicity
then it would imply that the Cepheid PL(V) and PL(K) zeropoints depend on
metallicity according to delta(M)/delta(Fe/H) ~0.66 in the sense that lower
metallicity Cepheids are intrinsically fainter. Medium-high resolution
spectroscopy for the main-sequence F stars in these two clusters is needed to
determine if metallicity really is the cause or whether some other explanation
applies.

</DOC>
<DOC>
<DOCNO> 100634 </DOCNO>
Groups quasi-isometric to H^2 x R


  This paper is a more succinct version of the author's 1993 UCLA mathematics
thesis. It proves that any group quasi-isometric to the product of the
hyperbolic plane with the real line is a finite extension of a cocompact
lattice in either the isometry group of the product of the hyperbolic plane
with the real line or the isometry group of the universal cover of SL(2,R).

</DOC>
<DOC>
<DOCNO> 101271 </DOCNO>
The uniformizing differential equation of the complex hyperbolic


  The relation between the uniformizing equation of the complex hyperbolic
structure on the moduli space of marked cubic surfaces and an Appell-Lauricella
hypergeometric system in nine variables is clarified.

</DOC>
<DOC>
<DOCNO> 152274 </DOCNO>
Sigma model approach to string theory effective actions with tachyons


  Motivated by recent discussions of actions for tachyon and vector fields
related to tachyon condensation in open string theory we review and clarify
some aspects of their derivation within sigma model approach. In particular, we
demonstrate that the renormalized partition function $Z(T,A)$ of boundary sigma
model gives the effective action for massless vectors which is consistent with
string S-matrix and beta function, resolving an old problem with this
suggestion in bosonic string case at the level of the leading $F^2 (dF)^2$
derivative corrections to Born-Infeld action. We give manifestly gauge
invariant definition of $Z(T,A)$ in non-abelian NSR open string theory and
check that its derivative reproduces the tachyon beta function in a particular
scheme. We also discuss derivation of similar actions for tachyon and massless
modes in closed bosonic and NSR (type 0) string theories.

</DOC>
<DOC>
<DOCNO> 152347 </DOCNO>
Static Solution in Source-Free SU(2) Yang-Mills Theory


  We show that a non-trivial topological effect breaks the conformal invariance
of pure Yang-Mills theory. Thus it is possible that classic particle-like
solutions exists in pure non-Abelian Yang-Mills theory. We find a static,
non-singular solution in source-free SU(2) Yang-Mills theory in
four-dimensional Minkowski space. This solution is a stable soliton
characterized by non-trivial topology and imaginary $A_0^a$, i.e.,
$A_0^aA_0^a<0$. It yields hermitian Hamilton, and finite, positive energy.

</DOC>
<DOC>
<DOCNO> 70857 </DOCNO>
Optical activity of a neutrino sea in the Standard Model


  We present the Standard Model calculation of the optical activity of a
neutrino sea

</DOC>
<DOC>
<DOCNO> 11963 </DOCNO>
Electronic coherence in mixed-valence systems: Spectral analysis


  The electron transfer kinetics of mixed-valence systems is studied via
solving the eigen-structure of the two-state non-adiabatic diffusion operator
for a wide range of electronic coupling constants and energy bias constants.
The calculated spectral structure consists of three branches in the
eigen-diagram, a real branch corresponding to exponential or multi-exponential
decay and two symmetric branches corresponding to population oscillations
between donor and acceptor states. The observed electronic coherence is shown
as a result of underdamped Rabi oscillations in an overdamped solvent
environment. The time-evolution of electron population is calculated by
applying the propagator constructed from the eigen-solution to the
non-equilibrium initial preparation, and it agrees perfectly with the result of
a direct numerical propagation of the density matrix. The resulting population
dynamics confirms that increasing the energy bias destroys electronic
coherence.

</DOC>
<DOC>
<DOCNO> 68205 </DOCNO>
Determination of the CKM unitarity triangle parameters by end 1999


  Within the Standard Model, a review of the current determination of the CKM
unitarity triangle parameters is presented, using experimental constraints from
the measurements of |epsilon_K|, V_ub/V_cb, Delta m_d and from the limit on
Delta m_s, available by end 1999.

</DOC>
<DOC>
<DOCNO> 40186 </DOCNO>
Unexplained Structure in (mu,pi) Invariant Mass Distributions


  Structures in invariant mass distributions from (mu,pi) combinations in the
range 0.380<mupi<0.470 GeV from neutrino and kaon experiments are presented in
comparable formats. No artifacts have been found to account for any part of the
structure. Hypotheses that the similarities are due to recurrent statistical
fluctuations are beyond credibility. My conclusion is that the similarities are
overwhelming evidence that the structure is of an unexplained physical origin.
It includes an enhancement which would accord with the decay of a narrow
(mu,pi) state of mass 0.429 GeV. The purpose of this report is to request and
enable every experimenter with precise mupi distributions to investigate their
degree of correspondence with these analyses.

</DOC>
<DOC>
<DOCNO> 174502 </DOCNO>
Incipient magnetic rotation? A magnetic dipole band in 104Cd


  High spin states of the nucleus 104Cd have been studied using the Gammapshere
array. The level scheme for 104Cd has been revised and evidence for a structure
consisting of magnetic dipole transitions is presented. Shell model
calculations, published previously, are invoked to support an interpretation of
this structure as an incpient case of magnetic rotation where the transversal
magnetic dipole moment is not strong enough to break the signature symmetry.

</DOC>
<DOC>
<DOCNO> 10925 </DOCNO>
Charge instabilities near a Van Hove singularity


  The charge instabilities of electron systems in the square lattice are
analyzed near the Van Hove singularity by means of a wilsonian renormalization
group approach. We show that the method preserves the spin rotational
invariance at all scales, allowing a rigorous determination of spin and charge
instabilities of the $t-t'$ Hubbard model. For $t'$ above $\approx 0.276 t$,
repulsive interactions fall into two different universality classes. One of
them has nonsingular response functions in the charge sector, while the other
is characterized by the splitting of the Van Hove singularity. At the level of
marginal perturbations, the Hubbard model turns out to be at the boundary
between the two universality classes, while extended models with
nearest-neighbor repulsive interactions belong to the latter class. In the case
of open systems allowed to exchange particles with a reservoir, we show the
existence of a range of fillings forbidden above and below the Van Hove
singularity. This has the property of attracting the Fermi level in the
mentioned range, as the system reaches its lowest energy when the Fermi energy
is at the singularity.

</DOC>
<DOC>
<DOCNO> 7854 </DOCNO>
Hydrodynamic theory for granular gases


  A granular gas subjected to a permanent injection of energy is described by
means of hydrodynamic equations derived from a moment expansion method. The
method uses as reference function not a Maxwellian distribution $f_{\sf M}$ but
a distribution $f_0 = \Phi f_{\sf M}$, such that $\Phi$ adds a fourth cumulant
$\kappa$ to the velocity distribution. The formalism is applied to a stationary
conductive case showing that the theory fits extraordinarily well the results
coming from our molecular dynamic simulations once we determine $\kappa$ as a
function of the inelasticity of the particle-particle collisions. The shape of
$\kappa$ is independent of the size $N$ of the system.

</DOC>
<DOC>
<DOCNO> 13242 </DOCNO>
Magnon dispersion and thermodynamics in CsNiF_3


  We present an accurate transfer matrix renormalization group calculation of
the thermodynamics in a quantum spin-1 planar ferromagnetic chain. We also
calculate the field dependence of the magnon gap and confirm the accuracy of
the magnon dispersion derived earlier through an 1/n expansion. We are thus
able to examine the validity of a number of previous calculations and further
analyze a wide range of experiments on CsNiF_3 concerning the magnon
dispersion, magnetization, susceptibility, and specific heat. Although it is
not possible to account for all data with a single set of parameters, the
overall qualitative agreement is good and the remaining discrepancies may
reflect departure from ideal quasi-one-dimensional model behavior. Finally, we
present some indirect evidence to the effect that the popular interpretation of
the excess specific heat in terms of sine-Gordon solitons may not be
appropriate.

</DOC>
<DOC>
<DOCNO> 70348 </DOCNO>
Maximal $\nu_\mu - \nu_\tau$ oscillations, the see-saw mechanism and the


  We examine one simple mechanism which leads to approximate maximal $\nu_\mu -
\nu_\tau$ oscillations in the standard see-saw model. In particular, we show
that this scheme could be implemented in the Exact Parity Model (also known as
the mirror matter model). Within this framework the solar neutrino problem is
solved by maximal $\nu_e \to \nu'_e$ oscillations (with $\nu'_e$ is the
essentially sterile mirror partner of $\nu_e$) and the LSND evidence for $\nu_e
\to \nu_\mu$ oscillations can also be explained.

</DOC>
<DOC>
<DOCNO> 123181 </DOCNO>
Dynamical family properties and dark halo scaling relations of giant


  Based on a uniform dynamical analysis of line-profile shapes for 21 luminous
round elliptical galaxies, we have investigated the dynamical family relations
of ellipticals: (i) The circular velocity curves (CVCs) of elliptical galaxies
are flat to within ~10% for R>~0.2R_e. (ii) Most ellipticals are moderately
radially anisotropic; their dynamical structure is surprisingly uniform. (iii)
Elliptical galaxies follow a Tully-Fisher (TF) relation, with v_c^max=300 km/s
for an L_B^* galaxy. At given v_c^max, they are ~1 mag fainter in B and appear
to have slightly lower baryonic mass than spirals even for maximum M/L_B. (iv)
The luminosity dependence of M/L_B is confirmed. The tilt of the Fundamental
Plane is not caused by dynamical non-homology, nor only by an increasing dark
matter fraction with L. It is, however, consistent with stellar population
models based on published metallicities and ages. The main driver is therefore
probably metallicity, and a secondary population effect is needed to explain
the K-band tilt. (v) These results make it likely that elliptical galaxies have
nearly maximal M/L_B (minimal halos). (vi) Despite the uniformly flat CVCs,
there is a spread in cumulative M/L_B(r). Some galaxies have no indication for
dark matter within 2R_e, whereas others have local M/L_Bs of 20-30 at 2R_e.
(vii) In models with maximum stellar mass, the dark matter contributes ~10-40%
of the mass within R_e. (viii) The corresponding halo core densities and
phase-space densities are at least ~25 times larger and the halo core radii ~4
times smaller than in spiral galaxies of the same v_c^max. The increase in M/L
sets in at ~10 times larger acceleration than in spirals. This could imply that
elliptical galaxy halos collapsed at high redshift or that some of the dark
matter in ellipticals might be baryonic. (abridged)

</DOC>
<DOC>
<DOCNO> 11528 </DOCNO>
Simulations on Infinite Size Lattices


  We introduce a Monte Carlo method, as a modification of existing cluster
algorithms, which allows simulations directly on systems of infinite size, and
for quantum models also at beta=infinity. All two-point functions can be
obtained, including dynamical information. When the number of iterations is
increased, correlation functions at larger distances become available. Limits q
-> 0 and omega -> 0 can be approached directly. As examples we calculate
spectra for the d=2 Ising model and for Heisenberg quantum spin ladders with 2
and 4 legs.

</DOC>
<DOC>
<DOCNO> 68139 </DOCNO>
Z-peak subtracted representation of Bhabha scattering and search for new


  We extend to the special case of Bhabha scattering the "Z-peak subtracted"
representation previously applied to e+e- to f f(bar) (f different from e).
This allows us to analyze the process at any energy while imposing in an
automatic way the constraints set by high precision measurements at the Z peak.
The procedure turns out to be particularly convenient for the search of a
certain class of new physics effects at variable energy. A few examples are
considered and the information thus obtained is combined with the corresponding
one that can be derived from the other e+e- annihilation processes, both at
present (LEP2) and at future colliders. This shows that the role of Bhabha
scattering in this respect can be quite relevant.

</DOC>
<DOC>
<DOCNO> 12658 </DOCNO>
Incommensurate magnetic structure of CeRhIn5


  The magnetic structure of the heavy fermion antiferromagnet CeRhIn5 is
determined using neutron diffraction. We find a magnetic wave vector
q_M=(1/2,1/2,0.297), which is temperature independent up to T_N=3.8K. A
staggered moment of 0.374(5) Bohr magneton at 1.4K, residing on the Ce ion,
spirals transversely along the c axis. The nearest neighbor moments on the
tetragonal basal plane are aligned antiferromagnetically.

</DOC>
<DOC>
<DOCNO> 123013 </DOCNO>
New method of extracting non-Gaussian signals


  We propose a new general method of extracting non-Gaussian features in a
given field. It sets the mean of the field to zero and renormalizes its Fourier
(or multipole) power to white noise, while keeping the phase information
unchanged. Using simulated cosmic microwave background (CMB) as an example, we
demonstrate the power of this method under many challenging circumstances. In
particular, we show its capability of detecting cosmic strings in the CMB.

</DOC>
<DOC>
<DOCNO> 13790 </DOCNO>
Coherent Umklapp Scattering of Light from Disordered Photonic Crystals


  A theoretical study of the coherent light scattering from disordered photonic
crystal is presented. In addition to the conventional enhancement of the
reflected light intensity into the backscattering direction, the so called
coherent backscattering (CBS), the periodic modulation of the dielectric
function in photonic crystals gives rise to a qualitatively new effect:
enhancement of the reflected light intensity in directions different from the
backscattering direction. These additional coherent scattering processes,
dubbed here {\em umklapp scattering} (CUS), result in peaks, which are most
pronounced when the incident light beam enters the sample at an angle close to
the the Bragg angle. Assuming that the dielectric function modulation is weak,
we study the shape of the CUS peaks for different relative lengths of the
modulation-induced Bragg attenuation compared to disorder-induced mean free
path. We show that when the Bragg length increases, then the CBS peak assumes
its conventional shape, whereas the CUS peak rapidly diminishes in amplitude.
We also study the suppression of the CUS peak upon the departure of the
incident beam from Bragg resonance: we found that the diminishing of the CUS
intensity is accompanied by substantial broadening. In addition, the peak
becomes asymmetric.

</DOC>
<DOC>
<DOCNO> 120405 </DOCNO>
The anomalous Galactic globular cluster NGC 2808


  We present UBVI photometry for about 60,000 stars in a region of 44'x33'
centered on the Galactic globular cluster (GGC) NGC 2808. The central region
has been mapped with the HST WFPC2 camera. We cover a field which extends from
the center to about 1.7 tidal radii. We confirm the anomalously elongated HB
with gaps along it, and we show that the gaps are statistically significant. We
find that: 1) the extended blue tail of HB (EBT) is present beyond
400''(=9r_h), and extends to V=21.2 also in these external regions; 2) also the
gaps on the EBT are present at least out to 400'' from the cluster center, and
possibly beyond that. The location of the gaps in the HB seems to be the same
all over the cluster. 3) there are no significant radial gradients in the
distribution of the stars in the HB. The observational facts presented in this
paper seem to exclude the possibility that the EBTs originate from tidal
stripping of the envelope of the RGB stars due to close encounters in high
density environments or to mass transfer in close binaries. Also, it is not
clear whether the presence of EBTs and gaps on them are the manifestation of
the same physical phenomenon. We have also shown that the jump recently
identified in the HB using Str"omgren-u photometry is clearly visible also in
the U, U-B plane, at T_e~11,600K. Finally, we present the luminosity function
(LF) of the RGB. The LF clearly shows the presence of the usual RGB bump, but
also a second feature, 1.4 magnitudes brighter in V, that we have named RGB
heap. The RGB heap, visible also in other GGCs, is a new feature that, because
of its position on the RGB, we have tentatively associated with the recently
discovered K giant variables.

</DOC>
<DOC>
<DOCNO> 170640 </DOCNO>
The spinor equation for the electromagnetic field


  We develop a spinor equation of the electromagnetic field, which is
equivalent to the Maxwell equation and has a similar form as the Dirac
equation. The spinor is the very conjugate momentum of the vector potential in
the Lagrangian mechanics. In this framework the electromagnetic field described
by the spinor exhibits the SU(2) internal symmetry. The quantization and the
problem of longinal and scalar photons are disscussed.

</DOC>
<DOC>
<DOCNO> 170208 </DOCNO>
Experimental realization of a highly structured search algorithm


  The highly structured search algorithm proposed by Hogg[Phys.Rev.Lett.
80,2473(1998)] is implemented experimentally for the 1-SAT problem in a single
search step by using nuclear magnetic resonance technique with two-qubit
sample. It is the first demonstration of the Hogg's algorithm, and can be
readily extended to solving 1-SAT problem for more qubits in one step if the
appropriate samples possessing more qubits are experimentally feasible.

</DOC>
<DOC>
<DOCNO> 122102 </DOCNO>
Formation and structure of halos in a warm dark matter cosmology


  (Abridged) Using high-resolution cosmological N-body simulations, we study
how the density profiles of dark matter halos are affected by the filtering of
the density power spectrum below a given scale length and by the introduction
of a thermal velocity dispersion. In the warm dark matter (WDM) scenario, both
the free-streaming scale, R_f, and the velocity dispersion, v_w, are determined
by the mass m_w of the WDM particle. We find that v_w is too small to affect
the density profiles of WDM halos. Down to the resolution attained in our
simulations, there is not any significant difference in the density profiles
and concentrations of halos obtained in simulations with and without the
inclusion of v_w. The density profiles of halos with masses down to ~0.01 the
filtering mass M_f can be described by the NFW shape; significant soft cores
are not formed. Nevertheless, the concentrations of these halos are lower than
those of the CDM counterparts and are approximately independent of mass. The
lower concentrations of WDM halos with respect to their CDM counterparts can be
accounted for their late formation epoch. Overall, our results point to a
series of advantages of a WDM model over the CDM one. In addition to solving
the substructure problem, a WDM model with R_f~0.16 Mpc (m_w~0.75 kev; flat
cosmology with Omega_L=h=0.7) also predicts concentrations, a Tully-Fisher
relation, and formation epochs for small halos which seems to be in better
agreement with observations, relative to CDM predictions.

</DOC>
<DOC>
<DOCNO> 178513 </DOCNO>
Antisymmetry in Strangeness -1 and -2 Three-Baryon Systems


  Using the generalized Pauli principle by adding particle labels to the usual
space and spin labels a symmetric Hamiltonian and a corresponding antisymmetric
wavefunction is constructed for systems of three baryons in the strangeness
sectors $S=-1$ and -2. Applications are the $\Xi NN-\Lambda\Lambda N$ and
$NN\Lambda -NN\Sigma$ systems.
  Minimal sets of generalized coupled Faddeev equations for breakup and
rearrangement operators as well as (possible) bound states are derived which
have the ordinary Pauli principle among identical particles built in. The
equations found confirm our previous sets of coupled Faddeev equations for
those systems whose derivation was carried through for distinguishable
particles and not using the generalized Pauli principle.

</DOC>
<DOC>
<DOCNO> 152486 </DOCNO>
Linear Dilaton Background and Fully Localized Intersecting Five-branes


  We investigate a near-horizon geometry of NS5-branes wrapping on a Riemann
surface, which asymptotically approaches to linear dilaton backgrounds. We
concretely find a fully localized solution of the near-horizon geometry of
intersecting NS5-branes. We also discuss a relation to a description of
Landau-Ginzburg theories.

</DOC>
<DOC>
<DOCNO> 40133 </DOCNO>
A new method to measure the CP violating angle gamma using B^\pm ->


  A new and simple procedure to measure the angle $\gamma$ from $B^{\pm} \to
\pi^{\pm}\pi^+\pi^-$ and $B^{\pm} \to K^{\pm}\pi^+\pi^-$ decays using SU(3)
symmetry is presented. It is based on a full Dalitz plot analysis of these
decays. All diagrams, including strong and electroweak penguins, are considered
in the procedure. The method is also free from final state interaction
problems. The theoretical error in the extraction of $\gamma$ within the method
should be of the order of $10^{\rm o}$ or even less. Taking into account the
B-meson production in the first generation of B factories and recent
measurements from CLEO, this method could bring the best measurement of
$\gamma$ in the next years.

</DOC>
<DOC>
<DOCNO> 7962 </DOCNO>
Heisenberg frustrated magnets: a nonperturbative approach


  Frustrated magnets are a notorious example where the usual perturbative
methods are in conflict. Using a nonperturbative Wilson-like approach, we get a
coherent picture of the physics of Heisenberg frustrated magnets everywhere
between $d=2$ and $d=4$. We recover all known perturbative results in a single
framework and find the transition to be weakly first order in $d=3$. We compute
effective exponents in good agreement with numerical and experimental data.

</DOC>
<DOC>
<DOCNO> 84555 </DOCNO>
Hypergravity and Categorical Feynmanology


  We propose a new line of attack to create a finite quantum theory which
includes general relativity and (perhaps) the standard model in its low energy
limit. The theory would emerge from the categorical approach. A structure is
observed on the category of unitary representations of the lorentz group which
we call hypergravity. This, combined with a study of the relationship between
Feynman diagrams and words in tensor categories, leads to the proposal.

</DOC>
<DOC>
<DOCNO> 68793 </DOCNO>
Inclusive weak decay rates of heavy hadrons


  A compact review of the theory, including some recent developments, of
inclusive weak decay rates of charmed and b hadrons with an emphasis on
predictions that can be tested in the forthcoming experiments.

</DOC>
<DOC>
<DOCNO> 119473 </DOCNO>
The Intergalactic Medium


  About half a million years after the Big Bang, the ever-fading cosmic
blackbody radiation cooled below 3000 K and shifted first into the infrared and
then into the radio, and the smooth baryonic plasma that filled the Universe
became neutral. The Universe then entered a ``dark age'' which persisted until
the first cosmic structures collapsed into gravitationally-bound systems, and
evolved into stars, galaxies, and black holes that lit up the Universe again.
Some time between redshift of 7 and 15, stars within protogalaxies created the
first heavy elements; these systems, together perhaps with an early population
of quasars, generated the ultraviolet radiation that reheated and reionized the
cosmos. The history of the Universe during and soon after these crucial
formative stages is recorded in the all-pervading intergalactic medium (IGM),
which is believed to contain most of the ordinary baryonic material left over
from the Big Bang. Throughout the epoch of structure formation, the IGM becomes
clumpy and acquires peculiar motions under the influence of gravity, and acts
as a source for the gas that gets accreted, cools, and forms stars within
galaxies, and as a sink for the metal enriched material, energy, and radiation
which they eject. Observations of absorption lines in quasar spectra at
redshifts up to 5 provide invaluable insight into the chemical composition of
the IGM and primordial density fluctuation spectrum of some of the earliest
formed cosmological structures, as well as of the ultraviolet background
radiation that ionizes them.

</DOC>
<DOC>
<DOCNO> 101098 </DOCNO>
Approximating Jones coefficients and other link invariants by Vassiliev


  We find approximations by Vassiliev invariants for the coefficients of the
Jones polynomial and all specializations of the HOMFLY and Kauffman
polynomials. Consequently, we obtain approximations of some other link
invariants arising from the homology of branched covers of links.

</DOC>
<DOC>
<DOCNO> 151831 </DOCNO>
D-Branes from N non-BPS D0-Branes


  In this paper we would like to show that from N non-BPS D0-branes in type IIB
theory we can obtain all BPS and non-BPS D-branes through the tachyon
condensation in the large N limit.

</DOC>
<DOC>
<DOCNO> 10248 </DOCNO>
Tricritical Points in the Sherrington-Kirkpatrick Model in the Presence


  The infinite-range-interaction Ising spin glass is considered in the presence
of an external random magnetic field following a trimodal (three-peak)
distribution. The model is studied through the replica method and phase
diagrams are obtained within the replica-symmetry approximation. It is shown
that the border of the ferromagnetic phase may present first-order phase
transitions, as well as tricritical points at finite temperatures. Analogous to
what happens for the Ising ferromagnet under a trimodal random field, it is
verified that the first-order phase transitions are directly related to the
dilution in the fields (represented by $p_{0}$). The ferromagnetic boundary at
zero temperature also exhibits an interesting behavior: for $0<p_{0}<p_{0}^{*}
\approx 0.30856$, a single tricritical point occurs, whereas if
$p_{0}>p_{0}^{*}$ the critical frontier is completely continuous; however, for
$p_{0}=p_{0}^{*}$, a fourth-order critical point appears. The stability
analysis of the replica-symmetric solution is performed and the regions of
validity of such a solution are identified; in particular, the Almeida-Thouless
line in the plane field versus temperature is shown to depend on the weight
$p_{0}$.

</DOC>
<DOC>
<DOCNO> 13647 </DOCNO>
Spin-wave theory for finite classical magnets and superparamagnetic


  Analytical calculations based on finite-size spin-wave theory and Monte Carlo
(MC) simulations are performed to investigate the validity of the well-known
relation m(H,T)=M(H,T)B_D[M(H,T)NH/T] between the induced magnetization m of
the magnetic particle and its intrinsic magnetization M for the Ising and
isotropic classical models [B_D(x) is the Langevin function, D is the number of
spin components, N is the number of atoms in the particle]. It follows from
general arguments and from our analytical results for the Heisenberg model at T
<< T_c that this relation is not exact for any finite D and nonzero
temperature. Nevertheless, corrections to this formula remain very small
practically in the whole range T<T_c if N >> 1, as confirmed by our Monte Carlo
calculations. At T <~ T_c/4 there is a good agreement between the
 MC and finite-size spin-wave calculations for the field dependence of m and M
for the Heisenberg model with free boundary conditions.

</DOC>
<DOC>
<DOCNO> 40478 </DOCNO>
CKM Phases from CP Asymmetries


  Measuring phases in the Cabibbo-Kobayashi-Maskawa matrix through CP
asymmetries in B decays is a major goal of current and future experiments.
Methods based on charge-conjugation and isospin symmetries involve very little
theoretical uncertainties, while schemes based on flavor SU(3) involve
uncertainties due to SU(3) breaking. Resolving these uncertainties requires
further studies involving a dialogue between theory and experiments.

</DOC>
<DOC>
<DOCNO> 68325 </DOCNO>
Radiative corrections to the decay $H^+ \to W^+ A^0$


  Full one-loop electroweak corrections to the on-shell decay $H^+ \to W^+A^0$
are computed in the framework of models with two Higgs doublets (THDM). Such a
decay may be dominant for $H^{\pm}$ over a wide range of parameter space
relevant at present and future colliders. We show that the corrections may
approach 40% and in particular are sensitive to $\lambda_5$, which parametrizes
the discrete symmetry breaking term. We suggest that a measurement of the
branching ratio of $H^+ \to W^+A^0$ may offer a possibility of measuring the
magnitude of $\lambda_5$.

</DOC>
<DOC>
<DOCNO> 119000 </DOCNO>
Non-Gaussianity vs. non-linearity of cosmological perturbations


  Following the discovery of the CMB, the hot big-bang model has become the
standard cosmological model. In this theory, small primordial fluctuations are
subsequently amplified by gravity to form the large-scale structure seen today.
Different theories for unified models of particle physics, lead to different
predictions for the statistical properties of the primordial fluctuations, that
can be divided in two classes: gaussian and non-gaussian. Convincing evidence
against or for gaussian initial conditions would rule out many scenarios and
point us towards a physical theory for the origin of structures. The
statistical distribution of cosmological perturbations, as we observe them, can
deviate from the gaussian distribution in several different ways. Even if
perturbations start off gaussian, non-linear gravitational evolution can
introduce non-gaussian features. Additionally, our knowledge of the Universe
comes principally from the study of luminous material such as galaxies, but
these might not be faithful tracers of the underlying mass distribution. The
relationship between fluctuations in the mass and in the galaxies distribution
(bias), is often assumed to be local, but could well be non-linear. Moreover,
galaxy catalogues use the redshift as third spatial coordinate: the resulting
redshift-space map is non-linearly distorted by peculiar velocities. Non-linear
gravitational evolution, biasing, and redshift-space distortion introduce
non-gaussianity, even in an initially gaussian fluctuation field. I will
investigate the statistical tools that allow us, in principle, to disentangle
the above different effects, and the observational datasets we require to do so
in practice.

</DOC>
<DOC>
<DOCNO> 12496 </DOCNO>
Observation of Umklapp processes in non-crystalline materials


  Umklapp processes are known to exist in cristalline materials, where they
control important properties such as thermal conductivity, heat capacity and
electrical conductivity. In this work we report the provocative observation of
Umklapp processes in a non-periodical system, namely liquid Lithium. The lack
of a well defined periodicity seems then not to prevent the existence of these
scattering processes mechanisms provided that the local order of the systems
i.e. the maxima of the static structure factor supply the equivalent of a
reciprocal lattice vector in the case of cristalline materials.

</DOC>
<DOC>
<DOCNO> 69976 </DOCNO>
Automatic Computation of Cross Sections in HEP


  For the study of reactions in High Energy Physics (HEP) automatic computation
systems have been developed and are widely used nowadays. GRACE is one of such
systems and it has achieved much success in analyzing experimental data. Since
we deal with the cross section whose value can be given by calculating hundreds
of Feynman diagrams, we manage the large scale calculation, so that effective
symbolic manipulation, the treat of singularity in the numerical integration
are required. The talk will describe the software design of GRACE system and
computational techniques in the GRACE.

</DOC>
<DOC>
<DOCNO> 83181 </DOCNO>
A Theory of Universal Artificial Intelligence based on Algorithmic


  Decision theory formally solves the problem of rational agents in uncertain
worlds if the true environmental prior probability distribution is known.
Solomonoff's theory of universal induction formally solves the problem of
sequence prediction for unknown prior distribution. We combine both ideas and
get a parameterless theory of universal Artificial Intelligence. We give strong
arguments that the resulting AIXI model is the most intelligent unbiased agent
possible. We outline for a number of problem classes, including sequence
prediction, strategic games, function minimization, reinforcement and
supervised learning, how the AIXI model can formally solve them. The major
drawback of the AIXI model is that it is uncomputable. To overcome this
problem, we construct a modified algorithm AIXI-tl, which is still effectively
more intelligent than any other time t and space l bounded agent. The
computation time of AIXI-tl is of the order tx2^l. Other discussed topics are
formal definitions of intelligence order relations, the horizon problem and
relations of the AIXI theory to other AI approaches.

</DOC>
<DOC>
<DOCNO> 10306 </DOCNO>
Anomalous dimensions and phase transitions in superconductors


  The anomalous scaling in the Ginzburg-Landau model for the superconducting
phase transition is studied. It is argued that the negative sign of the $\eta$
exponent is a consequence of a special singular behavior in momentum space. The
negative sign of $\eta$ comes from the divergence of the critical correlation
function at finite distances. This behavior implies the existence of a Lifshitz
point in the phase diagram. The anomalous scaling of the vector potential is
also discussed. It is shown that the anomalous dimension of the vector
potential $\eta_A=4-d$ has important consequences for the critical dynamics in
superconductors. The frequency-dependent conductivity is shown to obey the
scaling $\sigma(\omega)\sim\xi^{z-2}$. The prediction $z\approx 3.7$ is
obtained from existing Monte Carlo data.

</DOC>
<DOC>
<DOCNO> 68391 </DOCNO>
Generating functionals method of N.N.Bogolyubov and multiple production


  The generating functionals (GF) method in Bogolyubov's formulation and its
application for particle physics is considered. Effectiveness of the method is
illustrated by two examples. So, GF method can be used as the technical trick
solving the infinite sequence of algebraic equations. We will consider the
example, where GF allows express the multiplicity distributions (topological
cross sections) through the particles correlation functions (inclusive cross
sections) to `predict' so called the Koba-Nielsen-Olesen scaling. We will use
the GF to define validity of the thermal description of the multiple production
phenomena also. It will be seen that this will lead to the `correlations
relaxation condition' of N.N.Bogolyubov. This will allow to offer the
experimentally measurable criteria of applicability of thermodynamical
description of multiple production processes. In results we will find the
closed form of perturbation theory applicable for kinetic phase of
nonequilibrium processes. It is shown a way as the approach may be adapted to
the definite external conditions.

</DOC>
<DOC>
<DOCNO> 178581 </DOCNO>
Rotational Structure of T=0 and T=1 bands in the N=Z Nucleus 62Ga


  The rotational behaviour of T=0 and T=1 bands in the odd-odd N=Z nucleus 62Ga
is studied theoretically using the spherical shell model (laboratory frame) and
the cranked Nilsson-Strutinsky model (intrinsic frame). Both models give a good
description of available experimental data. The role of isoscalar and isovector
pairing in the T=0 and T=1 bands as functions of angular momentum is studied in
the shell model. The observed backbending in the T=0 band is interpreted as an
unpaired band-crossing between two configurations with different deformation.
The two configurations differ by 2p-2h and are found to terminate the
rotational properties at I\pi=9+ and I\pi=17+, respectively. E2-decay matrix
elements and spectroscopic quadrupole moments are calculated. From the CNS
calculation, supported by shell model results, it is suggested that the low
spin parts of the bands with T=0 and T=1 correspond to triaxially deformed
states with the rotation taking place around the shortest axis (positive
\gamma) and intermediate axis (negative \gamma), respectively. At lower spins
the configuration space pf_{5/2}g_{9/2}, used in the shell model calculation,
is found sufficient while also f_{7/2} becomes important above the backbending.

</DOC>
<DOC>
<DOCNO> 150875 </DOCNO>
Duffin-Kemmer-Petiau and Klein-Gordon-Fock Equations for


  Starting from Generating functional for Green Function (GF), constracted from
Lagrangian action in Duffin-Kemmer-Petiau (DKP) theory (L-approach) we strictly
prove that the physical matrix elements of S-matrix in DKP and
Klein-Gordon-Fock (KGF) theories coincide in cases of interaction spin O
particles with external and quantized Maxwell and Yang-Mills fields and in case
of external gravitational field (without or with torsion). For the proof we use
reduction formulas of Lehmann Symanzik, Zimmermann (LSZ). We prove that many
photons and Yang-Mills particles GF coincide in the both theories, too.

</DOC>
<DOC>
<DOCNO> 11896 </DOCNO>
Inevitable irreversibility in a quantum system consisting of many


  We review the recent result of Sato, Sekimoto, Hondou, and Takagi
(cond-mat/0008393) on the irreversibility inevitably observed in systems
consisting of many non-interacting ``small'' pieces. We focus on quantum
models, and supply an explicit lower bound for the work required to complete a
cyclic process.

</DOC>
<DOC>
<DOCNO> 120161 </DOCNO>
On Physical Interpretation of the Poynting-Robertson Effect


  Comments to the statements of Srikanth (1999) are presented. As for the
standard definition of the Poynting-Robertson drag, the results of Srikanth
(1999) are incorrect. Srikanth's statements about the isothermality condition
and ``red-shift'' are also discussed. Srikanth's results are generalized for
the most general case of the equation of motion when momentum loss per unit
time is proportional to -v/c (higher orders are neglected), where v is
(heliocentric) velocity of the particle, c is the speed of light.

</DOC>
<DOC>
<DOCNO> 117361 </DOCNO>
On Luminosity and morphology segregation in the Southern Sky Redshift


  The results are still valid, however this letter is superceeded by a
significantly extended version which is available at astro-ph/0003358 and is
scheduled for publication in the ApJ Dec. 10, 2000. We have withdrawn this
letter to avoid confusion.

</DOC>
<DOC>
<DOCNO> 120990 </DOCNO>
Cosmological Relativity: A General-Relativistic Theory for the


  Recent observations of distant supernovae imply, in defiance of expectations,
that the universe growth is accelerating, contrary to what has always been
assumed that the expansion is slowing down due to gravity. In this paper a
general-relativistic cosmological theory that gives a direct relationship
between distances and redshifts in an expanding universe is presented. The
theory is actually a generalization of Hubble's law taking gravity into account
by means of Einstein's theory of general relativity. The theory predicts that
the universe can have three phases of expansion, decelerating, constant and
accelerating, but it is shown that at present the first two cases are excluded,
although in the past it had experienced them. Our theory shows that the
universe now is definitely in the stage of accelerating expansion, confirming
the recent experimental results.

</DOC>
<DOC>
<DOCNO> 101107 </DOCNO>
Density preserving functions


  The property that a one to one function from the natural numbers to itself
preserves the density of sub-sets is shown to be equivalent to a condition on
the covering of intervals in the range of the function by images of intervals
in the domain of the function.

</DOC>
<DOC>
<DOCNO> 116764 </DOCNO>
Explanation of Faraday's Experiment by the Time-Space Model of Wave


  It is shown by the means of Time-Space Model of Wave Propagation the
underlying phenomena of the alternating current's origin in famous Faraday's
experiment.

</DOC>
<DOC>
<DOCNO> 123146 </DOCNO>
Neutralino Gamma-ray Signals from Accreting Halo Dark Matter


  There is mounting evidence that a self-consistent model for particle cold
dark matter has to take into consideration spatial inhomogeneities on
sub-galactic scales seen, for instance, in high-resolution N-body simulations
of structure formation. Also in more idealized, analytic models, there appear
density enhancements in certain regions of the halo. We use the results from a
recent N-body simulation of the Milky Way halo and investigate the gamma-ray
flux which would be produced when a specific dark matter candidate, the
neutralino, annihilates in regions of enhanced density. The clumpiness found on
all scales in the simulation results in very strong gamma-ray signals which
seem to already rule out some regions of the supersymmetric parameter space,
and would be further probed by upcoming experiments, such as the GLAST
gamma-ray satellite. As an orthogonal model of structure formation, we also
consider Sikivie's simple infall model of dark matter which predicts that there
should exist continuous regions of enhanced density, caustic rings, in the dark
matter halo of the Milky Way. We find, however, that the gamma-ray signal from
caustic rings is generally too small to be detectable.

</DOC>
<DOC>
<DOCNO> 100318 </DOCNO>
General Spinor Structures on Quantum Spaces


  A general theory of quantum spinor structures on quantum spaces is presented,
within the conceptual framework of the formalism of quantum principal bundles.
Quantum analogs of all basic objects of the classical theory are constructed
and analyzed. This includes Laplace and Dirac operators, quantum versions of
Clifford and spinor bundles, a Hodge *-operator, appropriate integration
operators, and mutual relations of these objects. We also present a
self-contained formalism of braided Clifford algebras. Quantum phenomena
appearing in the theory are discussed, including a very interesting example of
the Dirac operator associated to a quantum Hopf fibration.

</DOC>
<DOC>
<DOCNO> 69265 </DOCNO>
Relating m_Higgs to m_SUSY by a loop factor


  We assume that the scale of the soft supersymmetry breaking masses, m_SUSY,
sliding at tree level, is fixed by the minimization of the potential, but
without a significant contribution of the cosmological term. Under these
assumptions the electroweak breaking scale gets related to m_SUSY by a loop
factor. Applied to specific models of supersymmetry breaking, this mechanism
naturally gives sparticles slightly above all present accelerator bounds.

</DOC>
<DOC>
<DOCNO> 40603 </DOCNO>
Light mesons and charm decays: New results from E791


  We will discuss how the decays of charm mesons can be used to study light
mesons spectroscopy, by presenting recent results of Dalitz plot analyses using
data from Fermilab experiment E791. Emphasis will be on scalar mesons, which
are found to have large contribution to the $D$ decays studied. In addition to
the usual extraction of decay fractions and relative phases of the intermediate
amplitudes, the Dalitz plot technique is used to measure masses and widths of
scalar resonances. From the $D_s$ decay, we obtain masses and widths of
$f_0(980)$ and $f_0(1370)$. We find evidence for a light and broad scalar
resonance, the $\sigma$ meson, in $D^+\to\pi^-\pi^+\pi^+$ decay. Preliminary
studies also show evidence for a light and broad resonance, the $\kappa$ meson,
in $D^+\to K^-\pi^+\pi^+$ decay. These results illustrate the potential of
charm decays as a laboratory for the study of light mesons.

</DOC>
<DOC>
<DOCNO> 102318 </DOCNO>
Oriented Lagrangian Orthogonal Matroid Representations


  In this paper we extend the theory of oriented matroids to Lagrangian
orthogonal matroids and their representations, and give a completely natural
transformation from a representation of a classical oriented matroid to a
representation of the same oriented matroid considered as a Lagrangian
orthogonal matroid. Classical concepts of orientation and this extension may
both be thought of as stratifications of thin Schubert cells into unions of
connected components.

</DOC>
<DOC>
<DOCNO> 10299 </DOCNO>
An anomalous alloy: Y_x Si_{1-x}


  We study via density functional-based molecular dynamics the structural and
dynamical properties of the rare earth silicon amorphous alloy Y_xSi_{1-x} for
x=0.093 and x=0.156. The Si network forms cavities in which a Y^{3+} cation is
entrapped. Its electrons are transferred to the Si network and are located in
the dangling bonds of the Si atoms that line the Y cavities. This leads to the
presence of low coordinated Si atoms that can be described as monovalent or
divalent anions. For x=0.156, the cavities touch each other and share Si atoms
that have two dangling bonds. The vibrational spectrum is similar to that of
amorphous Si. However, doping induces a shoulder at 70 cm^{-1} and a pronounced
peak at 180 cm^{-1} due to low coordinated Si.

</DOC>
<DOC>
<DOCNO> 39875 </DOCNO>
On the Drell-Levy-Yan Relation to $O(\alpha_s^2)$


  We study the validity of a relation by Drell, Levy and Yan (DLY) connecting
the deep inelastic structure (DIS) functions and the single-particle
fragmentation functions in e^+e^- annihilation which are defined in the
spacelike (q^2<0) and timelike (q^2>0) regions respectively. Here q denotes the
momentum of the virtual photon exchanged in the deep inelastic scattering
process or the annihilation process. An extension of the DLY-relation, which
originally was only derived in the scaling parton model, to all orders in QCD
leads to a connection between the two evolution kernels determining the
q^2-dependence of the DIS structure functions and the fragmentation functions
respectively. In relation to this we derive the transformation relations
between the space-and time-like splitting functions up to next-to-leading order
(NLO) and the coefficient functions up to NNLO both for unpolarized and
polarized scattering. It is shown that the evolution kernels describing the
combined singlet evolution for the structure functions F_2(x,Q^2), F_L(x,Q^2)
where Q^2=|q^2| or $F_2(x,Q^2), \partial F_2(x,Q^2)/\partial \ln(Q^2)$ and the
corresponding fragmentation functions satisfy the DLY relation up to
next-to-leading order. We also comment on a relation proposed by Gribov and
Lipatov.

</DOC>
<DOC>
<DOCNO> 40480 </DOCNO>
Studies of hadronic decays of Z0 bosons at SLD


  The latest SLD results on light-quark fragmentation and tests of
hadronisation models are presented

</DOC>
<DOC>
<DOCNO> 152440 </DOCNO>
Note on Four Dp-Branes at Angles


  In this note we analyse the dynamical potential of a system of four
$Dp$-branes at arbitrary angles. The equilibrium configurations for various
values of the relative angles and distances among branes are discussed. The
known configurations of parallel branes and brane-antibranes are obtained at
extrema of the dynamical potential.

</DOC>
<DOC>
<DOCNO> 69811 </DOCNO>
Higgs or dijet production in double rapidity gap events


  We quantify the rate of double diffractive Higgs/dijet production at $pp$ (or
$p\bar{p}$) colliders. The suppression due to QCD bremsstrahlung is calculated
perturbatively up to single $\log$ accuracy. The survival probability of the
rapidity gaps is discussed. A first comparison with experiment is made.

</DOC>
<DOC>
<DOCNO> 69808 </DOCNO>
Postdoctoral Working Report: Researches on Higgs and FCNC Physics


  In this report, instead to give comprehensive review on two important
research fields during my first term postdoctoral working period: Higgs and
FCNC physics, I will collect part of my recently works on it. Charged Higgs is
the distinguished signature of new physics, in this report, I review my two
works on charged Higgs associated production with top quark and $W$ boson at
hardron colliders. Our researches show that these two charged Higgs production
mechanisms are important channel not only in finding charged Higgs, but also in
studying the quantum structure of new physics. Flavor Changing Neutral Current
(FCNC) processes are forbidden at tree level in the Standard Model (SM), so
they act as the ground to test quantum structure of the SM and also very
important channel in finding new physics beyond the SM. In this report, I focus
on the studies on FCNC processes on linear colliders and in B-factories.

</DOC>
<DOC>
<DOCNO> 11848 </DOCNO>
Generalized Jordan-Wigner Transformations


  We introduce a new spin-fermion mapping, for arbitrary spin $S$ generating
the SU(2) group algebra, that constitutes a natural generalization of the
Jordan-Wigner transformation for $S=1/2$. The mapping, valid for regular
lattices in any spatial dimension $d$, serves to unravel hidden symmetries in
one representation that are manifest in the other. We illustrate the power of
the transformation by finding exact solutions to lattice models previously
unsolved by standard techniques. We also present a proof of the existence of
the Haldane gap in $S=$1 bilinear nearest-neighbors Heisenberg spin chains and
discuss the relevance of the mapping to models of strongly correlated
electrons. Moreover, we present a general spin-anyon mapping for the case $d
\leq 2$.

</DOC>
<DOC>
<DOCNO> 67973 </DOCNO>
Domain wall fermions in vector theories


  Applications of Domain Wall fermions to various vector-like lattice theories
are reviewed with an emphasis on QCD thermodynamics. Methods for improving
their chiral properties at strong coupling are discussed and results from
implementing them are presented.

</DOC>
<DOC>
<DOCNO> 10581 </DOCNO>
Magnetic resonance peak and nonmagnetic impurities


  Nonmagnetic Zn impurities are known to strongly suppress superconductivity.
We review their effects on the spin excitation spectrum in $\rm
YBa_2Cu_3O_{7}$, as investigated by inelastic neutron scattering measurements.

</DOC>
<DOC>
<DOCNO> 68351 </DOCNO>
Cold and Fuzzy Dark Matter


  Cold dark matter (CDM) models predict small-scale structure in excess of
observations of the cores and abundance of dwarf galaxies. These problems might
be solved, and the virtues of CDM models retained, even without postulating
{\it ad hoc} dark matter particle or field interactions, if the dark matter is
composed of ultra-light scalar particles (m ~ 10^{-22}eV), initially in a
(cold) Bose-Einstein condensate, similar to axion dark matter models. The wave
properties of the dark matter stabilize gravitational collapse providing halo
cores and sharply suppressing small-scale linear power.

</DOC>
<DOC>
<DOCNO> 84192 </DOCNO>
From time inversion to nonlinear QED


  In Minkowski flat space-time, it is perceived that time inversion is unitary
rather than antiunitary, with energy being a time vector changing sign under
time inversion. The Dirac equation, in the case of electromagnetic interaction,
is not invariant under unitary time inversion, giving rise to a ``Klein
paradox''. To render unitary time inversion invariance, a nonlinear wave
equation is constructed, in which the ``Klein paradox'' disappears. In the case
of Coulomb interaction, the revised nonlinear equation can be linearized to
give energy solutions for Hydrogen-like ions without singularity when nuclear
number $Z>137$, showing a reversed energy order pending for experimental tests
such as Zeeman effects. In non-relativistic limit, this nonlinear equation
reduces to nonlinear schr\"odinger equation with soliton-like solutions.
Moreover, particle conjugation and electron-proton scattering with a
nonsingular current-potential interaction are discussed. Finally the explicit
form of gauge function is found, the uniqueness of Lorentz gauge is proven and
the Lagrangian density of quantum electrodynamics (QED) is revised as well. The
implementation of unitary time inversion leads to the ultimate derivation of
nonlinear QED.

</DOC>
<DOC>
<DOCNO> 170509 </DOCNO>
Entanglement of Quantum Evolutions


  The notion of entanglement can be naturally extended from quantum-states to
the level of general quantum evolutions. This is achieved by considering
multi-partite unitary transformations as elements of a multi-partite Hilbert
space and then extended to general quantum operations. We show some connection
between this entanglement and the entangling capabilities of the quantum
evolution.

</DOC>
<DOC>
<DOCNO> 118781 </DOCNO>
The Equilibrium Structure of Cosmological Halos: From Dwarf Galaxies to


  A new model for the postcollapse equilibrium structure of virialized objects
which condense out of the cosmological background universe is described and
compared with observations and simulations of cosmological halos from dwarf
galaxies to X-ray clusters. The model is based upon the assumption that
virialized halos are isothermal, which leads to a prediction of a unique
nonsingular isothermal sphere for the equilibrium structure, with a core radius
which is approximately 1/30 times the size and a core density which is
proportional to the mean background density at the epoch of collapse. These
predicted nonsingular isothermal spheres are in good agreement with the
observations of the internal structure of dark-matter-dominated halos from
dwarf galaxies to X-ray clusters.

</DOC>
<DOC>
<DOCNO> 151926 </DOCNO>
Dilatonic quantum multi-brane-worlds


  d5 dilatonic gravity action with surface counterterms motivated by AdS/CFT
correspondence and with contributions of brane quantum CFTs is considered
around AdS-like bulk. The effective equations of motion are constructed. They
admit two (outer and inner) or multi-brane solutions where brane CFTs may be
different. The role of quantum brane CFT is in inducing of complicated brane
dilatonic gravity. For exponential bulk potentials the number of AdS-like bulk
spaces is found in analytical form.The correspondent flat or curved (de Sitter
or hyperbolic) dilatonic two branes are created, as a rule, thanks to quantum
effects. The observable early Universe may correspond to inflationary brane.
The found dilatonic quantum two brane-worlds usually contain the naked
singularity but in couple explicit examples the curvature is finite and horizon
(corresponding to wormhole-like space) appears.

</DOC>
<DOC>
<DOCNO> 84179 </DOCNO>
On electrodynamics of rapidly moving sources


  Rapidly moving sources create pairs in the vacuum and lose energy. In
consequence of this, the velocity of a charged body cannot approach the speed
of light closer than a certain limit which depends only on the coupling
constant. The vacuum back-reaction secures the observance of the conservation
laws. A source can lose up to 50% of energy and charge because of the vacuum
instability.

</DOC>
<DOC>
<DOCNO> 9328 </DOCNO>
In search for the vortex charge and the Cooper pair mass


  A novel experiment for determination of the charge related to vortices in
thin superconducting film is proposed and a number of related experimental
set-ups are also theoretically considered. The methods are based on the
Torricelli-Bernoulli effect in superconductors and the phenomenology of the
effect is briefly discussed. The vortex charge is expressed via the effective
mass of the Cooper pairs, thus both parameters, inaccessible by now, could be
simultaneously determined. The experiment would require layered
metal-insulator-superconductor structures and standard electronics employed in
kinetic measurements. The quality of the insulator-superconductor interface
should be high enough as to allow for observation of electric field effects
similar to those investigated in superconducting field-effect transistors. The
development of layer-by-layer growth technology of oxide superconductors
provides unique possibility for investigation of new fundamental effects in
these materials. In particular, the structures necessary for determination of
the vortex charge could be used to study the superconducting surface Hall
effect, Bernoulli effect, the superfluid density, etc.. In conclusion, the
systematic investigation of new effects in oxide superconductors is envisaged
as an important part of the material science underlying the oxide electronics.

</DOC>
<DOC>
<DOCNO> 178803 </DOCNO>
Thermodynamical description of heavy ion collisions


  We analyze the thermodynamical state of nuclear matter in transport
descriptions of heavy ion reactions. We determine thermodynamical variables
from an analysis of local momentum space distributions and compare to blast
model parameters from an analysis of fragment energy spectra. These
descriptions are applied to spectator and fireball matter in semi-central and
central Au+Au collisions at SIS-energies, respectively.

</DOC>
<DOC>
<DOCNO> 39968 </DOCNO>
Feasibility of a Next Generation Underground Water Cherenkov Detector:


  The feasibility of a next generation underground water Cherenkov detector is
examined and a conceptual design (UNO) is presented. The design has a linear
detector configuration with a total volume of 650 kton which is 13 times the
total volume of the Super-Kamiokande detector. It corresponds to a 20 times
increase in fiducial volume for physics analyses. The physics goals of UNO are
to increase the sensitivity of the searches for nucleon decays about a factor
of ten and to make precision measurements of the solar and atmospheric neutrino
properties. In addition, the detection sensitivity for Supernova neutrinos will
reach as far as the Andromeda galaxy.

</DOC>
<DOC>
<DOCNO> 85277 </DOCNO>
Late time acceleration in Brans Dicke Cosmology


  In this work we have investigated the possibility of having a late time
accelerated phase of the universe, suggested by recent supernova observation,
in the context of Brans Dicke (BD) theory with a symmetry breaking potential
and a matter field. We find that a perfect fluid matter field (pressureless and
with pressure) cannot support this acceleration but a fluid with dissipative
pressure can drive this late time acceleration. We have also calculated some
cosmological parameters in our model to match with observations.

</DOC>
<DOC>
<DOCNO> 69662 </DOCNO>
Analytic resummation for the quark form factor in QCD


  The quark form factor is known to exponentiate within the framework of
dimensionally regularized perturbative QCD. The logarithm of the form factor is
expressed in terms of integrals over the scale of the running coupling. I show
that these integrals can be evaluated explicitly and expressed in terms of
renormalization group invariant analytic functions of the coupling and of the
space--time dimension, to any order in renormalized perturbation theory.
Explicit expressions are given up two loops. To this order, all the infrared
and collinear singularities in the logarithm of the form factor resum to a
single pole in epsilon, whose residue is determined at one loop, plus powers of
logarithms of epsilon. This behavior is conjectured to extend to all loops.

</DOC>
<DOC>
<DOCNO> 100303 </DOCNO>
Toda equations for Hurwitz numbers


  We consider ramified coverings of P^1 with arbitrary ramification type over 0
and infinity and simple ramifications elsewhere and prove that the generating
function for the numbers of such coverings is a tau-function for the Toda
lattice hierarchy of Ueno and Takasaki.

</DOC>
<DOC>
<DOCNO> 122944 </DOCNO>
Chandra Grating Spectroscopy of the Seyfert Galaxy Ton S180


  This paper presents results from spectral observations of Ton S180 using
Chandra and ASCA. The data confirm the presence of the soft excess but the
Chandra LETG spectrum reveals it to be broad and smooth, rather than resolved
into individual emission lines. This excess may represent either a primary or
reprocessed continuum component or a blend of broad lines from an ionized
accretion disk. The occurrence of a similar feature in five other NLSy1s leads
us to conclude that this soft X-ray component may be a characteristic of
sources accreting at a very high rate. The X-ray spectrum shows no evidence for
absorption lines, indicating that if gas exists in the line-of-sight then it is
in a very high ionization-state or has an extremely broad velocity
distribution. The new ASCA data confirm that the narrow component of the Fe
Kalpha line peaks close to a rest-energy of 7 keV, indicating the presence of a
significant amount of highly-ionized material in the nuclear environs.

</DOC>
<DOC>
<DOCNO> 11035 </DOCNO>
Ohta-Jasnow-Kawasaki Approximation for Nonconserved Coarsening under


  We analytically study coarsening dynamics in a system with nonconserved
scalar order parameter, when a uniform time-independent shear flow is present.
We use an anisotropic version of the Ohta-Jasnow-Kawasaki approximation to
calculate the growth exponents in two and three dimensions: for d=3 the
exponents we find are the same as expected on the basis of simple scaling
arguments, that is 3/2 in the flow direction and 1/2 in all the other
directions, while for d=2 we find an unusual behavior, in that the domains
experience an unlimited narrowing for very large times and a nontrivial
dynamical scaling appears. In addition, we consider the case where an
oscillatory shear is applied to a two-dimensional system, finding in this case
a standard t^1/2 growth, modulated by periodic oscillations. We support our
two-dimensional results by means of numerical simulations and we propose to
test our predictions by experiments on twisted nematic liquid crystals.

</DOC>
<DOC>
<DOCNO> 70355 </DOCNO>
O(alpha^3 ln alpha) corrections to positronium decay rates


  We compute O(alpha^3 ln alpha) corrections to the decay rates of para- and
orthopositronium into two and three photons, respectively. For this calculation
we employ the nonrelativistic QED regularized dimensionally and we explain how
in this framework the logarithms of the fine structure constant can be
extracted.

</DOC>
<DOC>
<DOCNO> 122474 </DOCNO>
On the Nature of AX J2049.6+2939 and AX J2050.0+2914


  AX J2049.6+2939 is a compact X-ray source in the vicinity of the southern
blow-up region of the Cygnus Loop supernova remnant (Miyata et al. 1998a). This
source was the brightest X-ray source inside the
 Cygnus Loop observed during the ASCA survey project. The X-ray spectrum was
well fitted by a power-law function with a photon index of $-2.1
 \pm 0.1$. Short-term timing analysis was performed and no coherent pulsation
was found. Follow-up observations with ASCA have revealed a large variation in
X-ray intensity by a factor of $\simeq$ 50, whereas the spectral shape did not
change within the statistical uncertainties. In the second ASCA observation, we
found another X-ray source, AX J2050.0+2941, at the north east of AX
 J2049.6+2939. During the three ASCA observations, the X-ray intensity of AX
J2050.0+2941 varied by a factor of $\simeq$4. No coherent pulsations could be
found for AX J2050.0+2941.
 We have performed optical photometric and spectroscopic observations in the
vicinity of AX J2049.6+2939 at the Kitt Peak National Observatory
 (KPNO). As a result, all objects brighter than $B$-band magnitude of 22 in the
error box can be identified with normal stars. Combined with the
 X-ray results and the fact that there are no radio counterparts, AX
 J2049.6+2939 is not likely to be either an ordinary rotation-powered pulsar or
an AGN. The nature of AX J2049.6+2939 is still unclear and further observations
over a wide energy band are strongly required.
 As to AX J2050.0+2941, the long-term X-ray variability and the radio
counterpart suggests that it is an AGN.

</DOC>
<DOC>
<DOCNO> 102652 </DOCNO>
Tsygan formality and Duflo formula


  We prove the 0-(co)homology part of the conjecture on the cup-products on
tangent cohomology in the Tsygan formality [Sh2]. We discuss its applications
to the Duflo formula.

</DOC>
<DOC>
<DOCNO> 122576 </DOCNO>
Freely precessing neutron stars: Model and observations


  We present a model of a freely precessing neutron star which is then compared
against pulsar observations. The aim is to draw conclusions regarding the
structure of the star, and test theoretical ideas of crust-core coupling and
superfluidity. We argue that, on theoretical grounds, it is likely that the
core neutron superfluid does not participate in the free precession of the
crust. We apply our model to the handful of proposed observations of free
precession that have appeared in the literature. Assuming crust-only
precession, we find that all but one of the observations are consistent with
there not being any pinned crustal superfluid at all; the maximum amount of
pinned superfluid consistent with the observations is about 10^-10 of the total
stellar moment of inertia. However, the observations do not rule out the
possibility that the crust and neutron superfluid core precess as a single
unit. In this case the maximum amount of pinned superfluid consistent with the
observations is about 10^-8 of the total stellar moment of inertia. Both of
these values are many orders of magnitude less than the 10^-2 value predicted
by many theories of pulsar glitches. We conclude that superfluid pinning, at
least as it affects free precession, needs to be reconsidered.

</DOC>
<DOC>
<DOCNO> 119161 </DOCNO>
StarFinder: an IDL GUI based code to analyze crowded fields with


  StarFinder is a new code for the deep analysis of stellar fields, designed
for well-sampled images with high and low Strehl ratio. It is organized in the
form of a self-contained IDL widget-based application, with a 'user-friendly'
graphic interface. We give here a general description of the code along with
some applications to real data with space-invariant Point Spread Function
(PSF). We present also some methods to handle anisoplanatic effects in
wide-field Adaptive Optics (AO)observations.

</DOC>
<DOC>
<DOCNO> 99624 </DOCNO>
Generalized Nambu system on S^3 and spinors


  It is shown that the manifold S^3 can be equipped with a natural Nambu
structure arising out of a cross product on the tangent space. Further, the
group action of SU(2) on S^3 is shown to be Nambu action. Moreover, we compare
the action of SU(2) on spinors with that of a Nambu system.

</DOC>
<DOC>
<DOCNO> 13341 </DOCNO>
Shell Effects and Phase Separation in a Trapped Multi-Component Fermi


  Shell effects in the coordinate space can be seen with degenerate Fermi
vapors in non-uniform trapping potentials. In particular, below the Fermi
temperature, the density profile of a Fermi gas in a confining harmonic
potential is characterized by several local maxima. This effect is enhanced for
"magic numbers" of particles and in quasi-1D (cigar-shaped) configurations. In
the case of a multi-component Fermi vapor, the separation of Fermi components
in different spatial shells (phase-separation) depends on temperature, number
of particles and scattering length. We derive analytical formulas, based on
bifurcation theory, for the critical density of Fermions and the critical
chemical potential, which give rise to the phase-separation.

</DOC>
<DOC>
<DOCNO> 152278 </DOCNO>
Conformal Four Point Functions and the Operator Product Expansion


  Various aspects of the four point function for scalar fields in conformally
invariant theories are analysed. This depends on an arbitrary function of two
conformal invariants u,v. A recurrence relation for the function corresponding
to the contribution of an arbitrary spin field in the operator product
expansion to the four point function is derived. This is solved explicitly in
two and four dimensions in terms of ordinary hypergeometric functions of
variables z,x which are simply related to u,v. The operator product expansion
analysis is applied to the explicit expressions for the four point function
found for free scalar, fermion and vector field theories in four dimensions.
The results for four point functions obtained by using the AdS/CFT
correspondence are also analysed in terms of functions related to those
appearing in the operator product discussion.

</DOC>
<DOC>
<DOCNO> 11439 </DOCNO>
Time evolution of thermodynamic entropy for conservative and dissipative


  We consider several low--dimensional chaotic maps started in
far-from-equilibrium initial conditions and we study the process of relaxation
to equilibrium. In the case of conservative maps the Boltzmann-Gibbs entropy
S(t) increases linearly in time with a slope equal to the Kolmogorov-Sinai
entropy rate. The same result is obtained also for a simple case of dissipative
system, the logistic map, when considered in the chaotic regime. A very
interesting results is found at the chaos threshold. In this case, the usual
Boltzmann-Gibbs is not appropriate and in order to have a linear increase, as
for the chaotic case, we need to use the generalized q-dependent Tsallis
entropy $S_q(t)$ with a particular value of a q different from 1 (when q=1 the
generalized entropy reduces to the Boltzmann-Gibbs). The entropic index q
appears to be characteristic of the dynamical system.

</DOC>
<DOC>
<DOCNO> 71063 </DOCNO>
Neutrino Properties


  The experimental discovery that neutrinos almost certainly have masses and
mix raises a number of fundamental questions about the neutrinos. We discuss
what is presently known about the answers to these questions, and how we can
learn more.

</DOC>
<DOC>
<DOCNO> 170343 </DOCNO>
Curve crossing in linear potential grids: the quasidegeneracy


  The quasidegeneracy approximation [V. A. Yurovsky, A. Ben-Reuven, P. S.
Julienne, and Y. B. Band, J. Phys. B {\bf 32}, 1845 (1999)] is used here to
evaluate transition amplitudes for the problem of curve crossing in linear
potential grids involving two sets of parallel potentials. The approximation
describes phenomena, such as counterintuitive transitions and saturation
(incomplete population transfer), not predictable by the assumption of
independent crossings. Also, a new kind of oscillations due to quantum
interference (different from the well-known St\"uckelberg oscillations) is
disclosed, and its nature discussed. The approximation can find applications in
many fields of physics, where multistate curve crossing problems occur.

</DOC>
<DOC>
<DOCNO> 121882 </DOCNO>
Study of the Long-Term X-Ray Variability of a Possible Quasar RX


  Long-term variability and spectral properties of a possible quasar, RX
J0957.9+6903, were studied, utilizing 16 ASCA observations spanning 5.5 years.
The average 0.7--10 keV spectrum of RX J0957.9+6903 is well represented by a
power-law continuum of photon index 1.58 $\pm$ 0.03, and an absorption column
of $\sim$ 1$\times{\rm 10}^{21}$ ${\rm cm}^{-2}$. The 2--10 keV flux of RX
J0957.9+6903 varied by a factor of four over the period of six years, around a
mean of $\sim$ 8.8$\times {\rm 10}^{-12}$ erg ${\rm s}^{-1}$ ${\rm cm}^{-2}$.
Peak to peak variability within each observation was less than 25% on $\sim$ 1
day time scale. These properties support the classification of RX J0957.9+6903
as a quasar. The power spectrum density (PSD) was estimated in a "forward"
manner, over a frequency range of $10^{-8.2}$--$10^{-4.3}$ Hz, by utilizing the
structure function method and Monte-Carlo simulation assuming a broken
power-law type PSD. Then, the break frequency $f_{\rm b}$ of the PSD of RX
J0957.9+6903 has been constrained as 1/$f_{\rm b}$ = $1600^{+\infty}_{-1100}$
days, and the logarithmic slope of the high-frequency region of the PSD as
$\alpha$ = $-$1.55 $\pm$ 0.2. A comparison of the estimated PSDs is made
between RX J0957.9+6903 and the M81 nucleus, observed in the same field of
view.

</DOC>
<DOC>
<DOCNO> 121406 </DOCNO>
A Broad Fe-Kalpha Emission Line in the X-Ray Spectrum of the Quasar 3C


  The Fe-K line, an important physical diagnostic in the X-ray spectra of AGN,
has been notoriously difficult to measure in the high-luminosity, radio-loud
quasar 3C 273 (z=0.158). On the few occasions that it has been detected its
intrinsic width has been thought to be narrow (FWHM < 10,000 km/s) with an
equivalent width (EW) of a few tens of eV.This was consistent with the general
trend that as one goes from low to high luminosity AGNs the Fe-K line goes from
being strong (EW ~200-300 eV) and broad (FWHM ~ 100,000 km/s) to being weak and
narrow, or absent altogether. Here we present the results of new ASCA and RXTE
observations, together with archival ASCA data, and show for the first time
that the Fe-K line in 3C 273 is as broad as that seen in Seyfert 1. The line is
resolved in two of the observations, with a mean Gaussian width of 0.8 +/- 0.3
keV, or FWHM of 0.3 +/- 0.1c. The smallest and largest EW measured is 43 +/- 34
eV, and 133 (+52,-53) eV respectively (quasar frame). The Compton-reflection
continuum is less than 10% of that expected from a centrally illuminated
semi-infinite, face-on, Compton-thick disk, confirming previous studies that
Compton reflection is negligible in 3C 273. The largest values of the Fe-K line
EW are under-predicted if the line originates in the disk, unless a time lag
longer than several days between line and continuum and/or an over-abundance of
Fe is invoked. We cannot unambiguously constrain the disk inclination angle.
About 60 deg is preferred for a cold disk, while a face-on disk is allowed if
the ionization state of Fe is H-like.

</DOC>
<DOC>
<DOCNO> 150642 </DOCNO>
On the boundary Ising model with disorder operators


  We extend the well-known method of calculating bulk correlation functions of
the conformal Ising model via bosonisation to situations with boundaries.
Oshikawa and Affleck have found the boundary states of two decoupled Ising
models in terms of the orbifold of a single free boson compactified on a circle
of radius r=1; we adapt their results to include disorder operators. Using
these boundary states we calculate the expectation value of a single disorder
field on a cylinder with free boundary conditions and show that in the
appropriate limits we recover the standard and frustrated partition functions.
We also show how to calculate Ising correlation functions on the upper half
plane.

</DOC>
<DOC>
<DOCNO> 12087 </DOCNO>
Magnetic properties of a spin-1/2 quadrumer chain


  We study a novel S=1/2 cluster chain Hamiltonian which has recently been
proposed in the context of the charge ordered low-temperature phase of
alpha'-NaV2O5. We perform a detailed investigation of this model within a large
range of parameters using perturbation theory and Lanczos diagonalization.
Using model-specific local conservation laws and parameter-dependent mappings
to various effective low-energy Hamiltonians we uncover a rich phase diagram
and several regimes of gapful spin-excitations. We find that the overall
features of recent neutron scattering data on alpha'-NaV2O5 can be fitted
within this model, however using a set of parameters which seems unlikely.

</DOC>
<DOC>
<DOCNO> 68375 </DOCNO>
On the $\eta$ and f$_1$(1420) Couplings to the Nucleon


  We consider neutral pseudoscalar, $\eta $, and axial vector, $f_1(1420)$,
mesons in the OZI-rule-respecting flavor basis, $\lbrace (\bar s s), {1\over
\sqrt{2}}(\bar u u + \bar d d)\rbrace$, and suggest a scenario for their
coupling to the nucleon. Within this framework, the non--strange parts of the
$\eta N$ and f$_1 N$ couplings are modeled by means of triangular $a_0\pi N$,
and $K K^* (\Lambda /\Sigma)$ vertices, while the strange ones partly proceed
via Goldberger-Treiman relations, which have been concluded solely on the
grounds of current universality. The suggested model explains the observed
suppression of the $\eta N$ coupling with respect to the constituent quark
model expectations, and predicts the coupling of $f_1$ to the nucleon.

</DOC>
<DOC>
<DOCNO> 8117 </DOCNO>
Microwave Electrodynamics of Electron-Doped Cuprate Superconductors


  We report microwave cavity perturbation measurements of the temperature
dependence of the penetration depth, lambda(T), and conductivity, sigma(T) of
Pr_{2-x}Ce_{x}CuO_{4-delta} (PCCO) crystals, as well as parallel-plate
resonator measurements of lambda(T) in PCCO thin films. Penetration depth
measurements are also presented for a Nd_{2-x}Ce_{x}CuO_{4-delta} (NCCO)
crystal. We find that delta-lambda(T) has a power-law behavior for T<T_c/3, and
conclude that the electron-doped cuprate superconductors have nodes in the
superconducting gap. Furthermore, using the surface impedance, we have derived
the real part of the conductivity, sigma_1(T), below T_c and found a behavior
similar to that observed in hole-doped cuprates.

</DOC>
<DOC>
<DOCNO> 71441 </DOCNO>
Theoretical description of the total gamma*gamma* cross-section and its


  We perform a detailed analysis of the total inelastic cross-section for
gamma*gamma* collisions. Different contributions coming from the quark box
diagram, reggeons, the soft and hard pomeron are included. The QCD pomeron
contribution contains a dominant part of subleading effects which reduces its
intercept and delays the onset of the asymptotic pomeron to high energies.
Estimates of the cross-section for doubly-tagged (e+e- to e+e- hadrons) events
are presented and compared with the existing LEP data. Good agreement between
the theoretical results and the experimental data is found. We also comment on
the extraction of the BFKL pomeron intercept from the available LEP
measurements.

</DOC>
<DOC>
<DOCNO> 122697 </DOCNO>
Intracluster Supernova as a Possible Extra Energy Source of Clusters


  The observed luminosity -- temperature relation of clusters is considerably
steeper than that expected from a simple scaling relation. Although extra
energy input is a likely solution, its source has not been identified. We
propose intracluster supernova as a possible source, and also predict the
supernova rate in intracluster space as a critical test.

</DOC>
<DOC>
<DOCNO> 85275 </DOCNO>
The Behavior of Kasner Cosmologies with Induced Matter


  We extend the induced matter model, previously applied to a variety of
isotropic cases, to a generalization of Bianchi type-I anisotropic cosmologies.
The induced matter model is a 5D Kaluza-Klein approach in which assumptions of
compactness are relaxed for the fifth coordinate, leading to extra geometric
terms. One interpretation of these extra terms is to identify them as an
``induced matter'' contribution to the stress-energy tensor. In similar spirit,
we construct a five dimensional metric in which the spatial slices possess
Bianchi type-I geometry. We find a set of solutions for the five dimensional
Einstein equations, and determine the pressure and density of induced matter.
We comment on the long-term dynamics of the model, showing that the assumption
of positive density leads to the contraction over time of the fifth scale
factor.

</DOC>
<DOC>
<DOCNO> 151459 </DOCNO>
Higgs mechanism in the Randall-Sundrum model


  We consider the dimensional reduction of a bulk scalar field in the
Randall-Sundrum model. By allowing the scalar field to be non-minimally coupled
to the spacetime curvature we show that it is possible to generate spontaneous
symmetry breaking on the brane.

</DOC>
<DOC>
<DOCNO> 71315 </DOCNO>
Monopole-Particle Duality at Strong Electric Coupling


  This has been withdrawn by the author. A rewrite of some of the material is
currently in progress.

</DOC>
<DOC>
<DOCNO> 70420 </DOCNO>
Discovery and Identification of W' Bosons in e gamma to nu q +X


  We examine the sensitivity of the process e gamma to nu q +X to W' bosons
which arise in various extensions of the standard model. We consider photon
spectra from both the Weizsacker Williams process and from a backscattered
laser. The process is found to be sensitive to W' masses up to several TeV,
depending on the model, the center of mass energy, the integrated luminosity,
and assumptions regarding systematic errors. If extra gauge bosons were
discovered first in other experiments, the process could also be used to
measure W' couplings. This measurement would provide information that could be
used to unravel the underlying theory, complementary to measurements at the
Large Hadron Collider.

</DOC>
<DOC>
<DOCNO> 83187 </DOCNO>
Deciding first-order properties of locally tree-decomposable structures


  We introduce the concept of a class of graphs, or more generally, relational
structures, being locally tree-decomposable. There are numerous examples of
locally tree-decomposable classes, among them the class of planar graphs and
all classes of bounded valence or of bounded tree-width. We also consider a
slightly more general concept of a class of structures having bounded local
tree-width.
  We show that for each property P of structures that is definable in
first-order logic and for each locally tree-decomposable class C of graphs,
there is a linear time algorithm deciding whether a given structure A in C has
property P. For classes C of bounded local tree-width, we show that for every
k\ge 1 there is an algorithm that solves the same problem in time
O(n^{1+(1/k)}) (where n is the cardinality of the input structure).

</DOC>
<DOC>
<DOCNO> 8998 </DOCNO>
Anomalous temperature dependence of magnetic quantum oscillations in


  Shubnikov--de Haas (SdH) and Hall-effect measurements of CeBiPt and LaBiPt
reveal the presence of simple and very small Fermi surfaces with hole-like
charge carriers for both semimetals. In the magnetic material, CeBiPt, we
observe a strong temperature dependence of the SdH frequency. This highly
unusual effect might be connected with an internal exchange field within the
material and a strongly spin-dependent scattering of the charge carriers.

</DOC>
<DOC>
<DOCNO> 117262 </DOCNO>
Explicitly correlated trial wave functions in Quantum Monte Carlo


  We present a new form of explicitly correlated wave function whose parameters
are mainly linear, to circumvent the problem of the optimization of a large
number of non-linear parameters usually encountered with basis sets of
explicitly correlated wave functions. With this trial wave function we
succeeded in minimizing the energy instead of the variance of the local energy,
as is more common in quantum Monte Carlo methods. We applied this wave function
to the calculation of the energies of Be 3P (1s22p2) and Be- 4So (1s22p3) by
variational and diffusion Monte Carlo methods. The results compare favorably
with those obtained by different types of explicitly correlated trial wave
functions already described in the literature. The energies obtained are
improved with respect to the best variational ones found in literature, and
within one standard deviation from the estimated non-relativistic limits

</DOC>
<DOC>
<DOCNO> 12290 </DOCNO>
Decoherence, Correlation, and Entanglement in a Pair of Coupled Quantum


  A pair of coupled quantum dissipative oscillators, serving as a model for a
nanosystem, is here described by the Lindblad equation. Its dynamic evolution
is shown to exhibit the features of decoherence (spatial extent of quantum
behavior), correlation (spatial scale over which the system localizes to its
physical dimensions), and entanglement (a special quantum feature making its
appearance first in such bipartite systems) as a function of the coupling
constants of the Lindblad equation. One interesting feature emerging out of
this calculation is that the entanglement may exhibit revivals in time. An
initially entangled state need not remain so for all time and may exhibit
regions of nonentanglement. Interpreting the parameters of the Lindblad theory
as environmental features in certain experimental situations, this model
calculation gives us clues to possible control of decoherence, correlation, and
entanglement. We indicate possible interpretation of the Lindblad parameters as
control parameters in more general contexts of some recent experiments.

</DOC>
<DOC>
<DOCNO> 169947 </DOCNO>
Toward scalable quantum computation with cavity QED systems


  We propose a scheme for quantum computing using high-Q cavities in which the
qubits are represented by single cavity modes restricted in the space spanned
by the two lowest Fock states. We show that single qubit operations and
universal multiple qubit gates can be implemented using atoms sequentially
crossing the cavities.

</DOC>
<DOC>
<DOCNO> 119153 </DOCNO>
A New Method For Galaxy Cluster Detection I: The Algorithm


  Numerous methods for finding clusters at moderate to high redshifts have been
proposed in recent years, at wavelengths ranging from radio to X-rays. In this
paper we describe a new method for detecting clusters in two-band
optical/near-IR imaging data. The method relies upon the observation that all
rich clusters, at all redshifts observed so far, appear to have a red sequence
of early-type galaxies. The emerging picture is that all rich clusters contain
a core population of passively evolving elliptical galaxies which are coeval
and formed at high redshifts. The proposed search method exploits this strong
empirical fact by using the red sequence as a direct indicator of overdensity.
The fundamental advantage of this approach is that with appropriate filters,
cluster elliptical galaxies at a given redshift are redder than all normal
galaxies at lower redshifts. A simple color cut thus virtually eliminates all
foreground contamination, even at significant redshifts. In this paper, one of
a series of two, we describe the underlying assumptions and basic techniques of
the method in detail, and contrast the method with those used by other authors.
We provide a brief demonstration of the effectiveness of the technique using
real redshift data, and from this conclude that the method offers a powerful
yet simple way of identify galaxy clusters. We find that the method can
reliably detect structures to masses as small as groups with velocity
dispersions of only ~300 km/sec, with redshifts for all detected structures
estimated to an accuracy of ~10%.

</DOC>
<DOC>
<DOCNO> 40623 </DOCNO>
First Measurement of the Ratio B(t-->Wb)/B(t-->Wq) and Associated Limit


  We present the first measurement of the ratio of branching fraction R=
B(t-->wb)/B(t-->Wq) from ppbar collisions at sqrt(s)=1.8 TeV. The data set
corresponds to 109 pb-1 of data recorded by the Collider Detector at Fermilab
during the 1992-1995 Tevatron run. We measure R=0.94+.31-.24 (stat+syst) or
R>0.61 (0.56) at 90 (95) %C.L., in agreement with the standard model
predictions. This measurement yields a limit of the Cabibbo-Kobayashi-Maskawa
quark mixing matrix element Vtb under the assumption of three generation
unitarity.

</DOC>
<DOC>
<DOCNO> 150384 </DOCNO>
Randall-Sundrum Gauge in the Brane World


  We discuss the Randall-Sundrum (RS) choice for $h_{MN}$ in the brane-world.
We begin with the de Donder gauge (transverse-tracefree) including
scalar($h_{55}$), vector($h_{5\mu}$) and tensor($h_{\mu\nu}$) in five
dimensions for comparison. One finds that $h_{55}=0$ and $h_{5\mu}=0$. This
leads to the RS choice. It appears that the RS choice is so restrictive for the
five massless states, whereas it is unique for describing the massive states.
Furthermore, one can establish the stability of the RS solution with the RS
choice only.

</DOC>
<DOC>
<DOCNO> 121255 </DOCNO>
GLAST, the Gamma-ray Large Area Space Telescope


  GLAST, a detector for cosmic gamma rays in the range from 20 MeV to 300 GeV,
will be launched in space in 2005. Breakthroughs are expected in particular in
the study of particle acceleration mechanisms in space and of gamma ray bursts,
and maybe on the search for cold dark matter; but of course the most exciting
discoveries could come from the unexpected.

</DOC>
<DOC>
<DOCNO> 69178 </DOCNO>
Geophysical constraints on mirror matter within the Earth


  We have performed a detailed investigation of geophysical constraints on the
possible admixture of mirror matter inside the Earth. On the basis of the
Preliminary Reference Earth Model (PREM) -- the `Standard Model' of the Earth's
interior -- we have developed a method which allows one to compute changes in
various quantities characterising the Earth (mass, moment of inertia, normal
mode frequencies etc.)due to the presence of mirror matter. As a result we have
been able to obtain for the first time the direct upper bounds on the possible
concentration of the mirror matter in the Earth. In terms of the ratio of the
mirror mass to the Earth mass a conservative upper bound is $3.8\times
10^{-3}$. We then analysed possible mechanisms (such as lunar and solar tidal
forces, meteorite impacts and earthquakes) of exciting mirror matter
oscillations around the Earth centre. Such oscillations could manifest
themselves through global variations of the gravitational acceleration at the
Earth's surface. We conclude that such variations are too small to be observed.
Our results are valid for other types of hypothetical matter coupled to
ordinary matter by gravitation only (e.g. the shadow matter of superstring
theories).

</DOC>
<DOC>
<DOCNO> 12531 </DOCNO>
On the dephasing time of the chiral metal


  In the low-dimensional disordered systems the dephasing time and the
inelastic scattering (out-scattering) time are in general different. We show
that in the case of the two-dimensional chiral metal which is formed at the
surface of a layered three dimensional system, which is exhibiting the integer
quantum Hall effect these two quantities are essentially the same and their
temperature-dependence is T^(-3/2). In particular we show that the results
obtained using the diagramatic technique and the phase uncertainty approach
introduced by A. Stern et al. (Phys. Rev. A 41, 3436 (1990)) for the
out-scattering and the dephasing time respectively, coincide. We furthermore
consider these quantities in the case of the three-dimensional chiral metal,
where similar conclusions are reached.

</DOC>
<DOC>
<DOCNO> 169611 </DOCNO>
Probabilistic quantum cloning via Greenberger-Horne-Zeilinger states


  We propose a probabilistic quantum cloning scheme using
Greenberger-Horne-Zeilinger states, Bell basis measurements, single-qubit
unitary operations and generalized measurements, all of which are within the
reach of current technology. Compared to another possible scheme via Tele-CNOT
gate [D. Gottesman and I. L. Chuang, Nature 402, 390 (1999)], the present
scheme may be used in experiment to clone the states of one particle to those
of two different particles with higher probability and less GHZ resources.

</DOC>
<DOC>
<DOCNO> 120929 </DOCNO>
Validation of Up-the-Ramp Sampling with Cosmic Ray Rejection on IR


  We examine cosmic ray rejection methodology on data collected from InSb and
Si:As detectors. The application of an Up-the-Ramp sampling technique with
cosmic ray identification and mitigation is the focus of this study. This
technique is valuable for space-based observatories which are exposed to
high-radiation environments. We validate the Up-the-Ramp approach on
radiation-test data sets with InSb and Si:As detectors which were generated for
SIRTF. The Up-the-Ramp sampling method studied in this paper is over 99.9%
effective at removing cosmic rays and preserves the structure and photometric
quality of the image to well within the measurement error.

</DOC>
<DOC>
<DOCNO> 9380 </DOCNO>
Bipolaron Binding in Quantum Wires


  A theory of bipolaron states in quantum wires with a parabolic potential well
is developed applying the Feynman variational principle. The basic parameters
of the bipolaron ground state (the binding energy, the number of phonons in the
bipolaron cloud, the effective mass, and the bipolaron radius) are studied as a
function of sizes of the potential well. Two cases are considered in detail: a
cylindrical quantum wire and a planar quantum wire. Analytical expressions for
the bipolaron parameters are obtained at large and small sizes of the quantum
well. It is shown that at $R\gg 1$ [where $R$ means the radius (halfwidth) of a
cylindrical (planar) quantum wire, expressed in Feynman units], the influence
of confinement on the bipolaron binding energy is described by the function
$\sim 1/R^{2}$ for both cases, while at small sizes this influence is different
in each case. In quantum wires, the bipolaron binding energy $W(R) $ increases
logarithmically with decreasing radius. The shapes and the sizes of a
nanostructure, which are favorable for observation of stable bipolaron states,
are determined.

</DOC>
<DOC>
<DOCNO> 10763 </DOCNO>
Doped two orbital chains with strong Hund's rule couplings -


  Different models for doping of two-orbital chains with mobile $S=1/2$
fermions and strong, ferromagnetic (FM) Hund's rule couplings stabilizing the
S=1 spins are investigated by density matrix renormalization group (DMRG)
methods. The competition between antiferromagnetic (AF) and FM order leads to a
rich phase diagram with a narrow FM region for weak AF couplings and strongly
enhanced triplet pairing correlations. Without a level difference between the
orbitals, the spin gap persists upon doping, whereas gapless spin excitations
are generated by interactions among itinerant polarons in the presence of a
level difference. In the charge sector we find dominant singlet pairing
correlations without a level difference, whereas upon the inclusion of a
Coulomb repulsion between the orbitals or with a level difference, charge
density wave (CDW) correlations decay slowest. The string correlation functions
remain finite upon doping for all models.

</DOC>
<DOC>
<DOCNO> 12770 </DOCNO>
Dynamical stripe structure in La$_{2-x}$Sr$_x$CuO$_4$ observed by Raman


  The dynamical stripe structure relating to the "1/8 problem" was investigated
in La$_{2-x}$Sr$_x$CuO$_4$ utilizing the high frequency response of Raman
scattering. The split of the two-magnon peak due to the formation of the stripe
structure was observed at whole Sr concentration region from $x=0.035$ to 0.25
at low temperatures. Especially clear split was observed at low carrier
concentration region $x=0.035 - 0.06$ and at $x \sim 1/8$. The onset
temperatures of these stripe structures are as high as 300-350 K, which are
much higher than the temperatures measured by slow response probes.

</DOC>
<DOC>
<DOCNO> 118939 </DOCNO>
Turmoil on the accretion disk of GRO J1655-40


  During the 1996/1997 outburst of the X-ray transient GRO J1655-40 the Wide
Field Cameras onboard BeppoSAX observed the system with nearly continuous
coverage during some stages of this outburst. On two occasions we find clear
evidence for frequent dipping behaviour, characterized by several absorption
dips occurring within one binary orbit. However, during preceding and following
binary orbits there is no sign of such dips at the same range of orbital
phases. We also collected light curves of absorption dips as seen with other
X-ray instruments. Although the 65 dips that were collected occur preferably
between orbital phases 0.68 and 0.92, there is evidence that the morphology of
the material causing the dips is changing over just one binary orbit. The short
duration (~minutes) and phasing of the dips are discussed in the framework of
models where the stream from the companion star encounters a hot outer rim on
the accretion disk.

</DOC>
<DOC>
<DOCNO> 118324 </DOCNO>
Ionizing Radiation in Smoothed Particle Hydrodynamics


  A new method for the inclusion of ionizing radiation from uniform radiation
fields into 3D Smoothed Particle Hydrodynamics (SPHI) simulations is presented.
We calculate the optical depth for the Lyman continuum radiation from the
source towards the SPHI particles by ray-tracing integration. The
time-dependent ionization rate equation is then solved locally for the
particles within the ionizing radiation field. Using test calculations, we
explore the numerical behaviour of the code with respect to the implementation
of the time-dependent ionization rate equation. We also test the coupling of
the heating caused by the ionization to the hydrodynamical part of the SPHI
code.

</DOC>
<DOC>
<DOCNO> 170788 </DOCNO>
Quantum Entanglement and Quantum Computational Algorithms


  The existence of entangled quantum states gives extra power to quantum
computers over their classical counterparts. Quantum entanglement shows up
qualitatively at the level of two qubits. We show that if no entanglement is
envolved then whatever one can do with qubits can also be done with classical
optical systems. We demonstrate that the one- and the two-bit Deutsch-Jozsa
algorithm does not require entanglement and can be mapped onto a classical
optical scheme. It is only for three and more input bits that the DJ algorithm
requires the implementation of entangling transformations and in these cases it
is impossible to implement this algorithm classically.

</DOC>
<DOC>
<DOCNO> 123004 </DOCNO>
CMB anisotropy from spatial correlations of clusters of galaxies


  The SZ effect from clusters of galaxies is a dominant source of secondary CMB
anisotropy in the low-redshift universe. We present analytic predictions for
the CMB power spectrum from massive halos arising from the SZ effect. Since
halos are discrete, the power spectrum consists of a Poisson and a correlation
term. The latter is always smaller than the former, which is dominated by
nearby bright rich clusters. In practice however, those bright clusters are
easy to indentify and can thus be subtracted from the map. After this
subtraction, the correlation term dominates degree-scale fluctuations over the
Poisson term, as the main contribution to the correlation term comes from
distant clusters. We find that the correlation term is detectable by Planck
experiment. Since the degree scale spectrum is quite insensitive to the highly
uncertain core structures of halos, our predictions are robust on these scales.
Measuring the correlation term on degree scales thus cleanly probes the
clustering of distant halos. This has not been measured yet, mainly because
optical and X-ray surveys are not sufficiently sensitive to include such
distant clusters and groups. Our analytic predictions are also compared to
adiabatic hydrodynamic simulations. The agreement is remarkably good, down to
ten arcminutes scales, indicating that our predictions are robust for the
Planck experiment. Below ten arcminute scales, where the details of the core
structure dominates the power spectrum, our analytic and simulated predictions
might fail. In the near future, interferometer and bolometer array experiments
will measure the SZ power spectrum down to arcminutes scales, and yield new
insight into the physics of the intrahalo medium.

</DOC>
<DOC>
<DOCNO> 71855 </DOCNO>
Mapping the proton unintegrated gluon distribution in dijets


  We discuss how the dijet azimuthal correlations in DIS and real
photoproduction at HERA probe the differential (unintegrated) gluon
distribution in the proton. We find a strong dependence of the azimuthal
correlation pattern on Bjorken-$x$, photon virtuality and the cut on the jet
transverse momenta. A rise of the azimuthal decorrelations is observed with
decreasing Bjorken-x due to the interplay of perturbative and nonperturbative
effects. We predict a strong rise of the same-side jet rate with photon energy
for real photoproduction. We discuss conditions for the correlation function to
be dominated by hard perturbative gluons and ways of constraining the size of
the nonperturbative soft component. We make some predictions for the THERA
energy range. The analysis of the energy dependence of the isolated jet and
two-jet cross sections in photoproduction would be a new way to study the not
yet well constrained unintegrated gluon distributions and to explore the onset
of the pQCD regime.

</DOC>
<DOC>
<DOCNO> 150722 </DOCNO>
Regular and black-hole solutions of the Einstein-Yang-Mills-Higgs


  Regular and black-hole solutions of the spontaneously broken
Einstein-Yang-Mills-Higgs theory with nonminimal coupling to gravity are shown
to exist. The main characteristics of the solutions are presented and
differences with respect to the minimally coupled case are studied. Since
negative energy densities are found to be possible, traversable wormhole
solutions might exist. We prove that they are absent.

</DOC>
<DOC>
<DOCNO> 100616 </DOCNO>
Occupation Time Fluctuations in Branching Systems


  We consider particle systems in locally compact Abelian groups with particles
moving according to a process with symmetric stationary independent increments
and undergoing one and two levels of critical branching. We obtain long time
fluctuation limits for the occupation time process of the one-and two-level
systems. We give complete results for the case of finite variance branching,
where the fluctuation limits are Gaussian random fields, and partial results
for an example of infinite variance branching, where the fluctuation limits are
stable random fields. The asymptotics of the occupation time fluctuations are
determined by the Green potential operator G of the individual particle motion
and its powers $G^2, G^3$, and by the growth as $t\to\infty$ of the operator
$G_t=\int^t_0T_sds$ and its powers, where $T_t$ is the semigroup of the motion.
The results are illustrated with two examples of motions: the symmetric
$\alpha$-stable L\'evy process in $\erre^d$ $(0<\alpha\leq2)$,and the so called
c-hierarchical random walk in the hierarchical group of order N (0<c<N). We
show that the two motions have analogous asymptotics of $G_t$ and its powers
that depend on an order parameter $\gamma$ for their transience /recurrence
behavior. This parameter is $\gamma=d/\alpha-1$ for the $\alpha$-stable motion,
and $\gamma=\log c/\log (N/c)$ for the c-hierarchical random walk. As a
consequence of these analogies, the asymptotics of the occupation time
fluctuations of the corresponding branching particle systems are also
analogous. In the case of the c-hierarchical random walk, however, the growth
of $G_t$ and its powers is modulated by oscillations on a logarithmic time
scale.

</DOC>
<DOC>
<DOCNO> 120096 </DOCNO>
Cosmic Microwave Background Radiation anisotropy with primordial


  Galactic magnetic fields are observed of order $\sim 10^{-6}G$, but their
origin is not definitely known yet. In this paper we consider the primordial
magnetic fields generated in the early universe and analyse their effects on
the density perturbations and the CMBR anisotropy. We assume that the random
magnetic fields have the power law spectrum and satisfy the force-free field
condition.
 The peak heights of the CMBR anisotropy are shown to be shifted upward
depending on the magnetic field strengths relative to the no-magnetic field
case.

</DOC>
<DOC>
<DOCNO> 40164 </DOCNO>
Three-Pion Interferometry Results from Central Pb+Pb Collisions at 158 A


  Three-particle correlations have been measured for identified negative pions
from central 158 A GeV Pb+Pb collisions by the WA98 experiment at CERN. A
substantial contribution of the genuine three-body correlation has been found
as expected for a mainly chaotic and symmetric source.

</DOC>
<DOC>
<DOCNO> 68081 </DOCNO>
Constraints on Extra Gauge Bosons in e gamma Collisions


  We investigate the sensitivity of e- gamma ---> nu_e nu_mu(bar) mu- to extra
charged gauge bosons. The sensitivity is much below that of e-e+ ---> nu
nu(bar) gamma. We conclude that e- gamma ---> d u(bar) nu_e and e- gamma ---> f
f(bar) e- are also inferior to e+e- collisions in setting bounds on extra
charged and neutral gauge bosons and on four fermion contact interactions.

</DOC>
<DOC>
<DOCNO> 152285 </DOCNO>
The volume element of space-time and scale invariance


  Scale invariance is considered in the context of gravitational theories where
the action, in the first order formalism, is of the form $S = \int L_{1} \Phi
d^4x$ + $\int L_{2}\sqrt{-g}d^4x$ where the volume element $\Phi d^4x$ is
independent of the metric. For global scale invariance, a "dilaton" $\phi$ has
to be introduced, with non-trivial potentials $V(\phi)$ = $f_{1}e^{\alpha\phi}$
in $L_1$ and $U(\phi)$ = $f_{2}e^{2\alpha\phi}$ in $L_2$. This leads to
non-trivial mass generation and a potential for $\phi$ which is interesting for
inflation. Interpolating models for natural transition from inflation to a
slowly accelerated universe at late times appear naturally. This is also
achieved for "Quintessential models", which are scale invariant but formulated
with the use of volume element $\Phi d^4x$ alone. For closed strings and branes
(including the supersymmetric cases), the modified measure formulation is
possible and does not require the introduction of a particular scale (the
string or brane tension) from the begining but rather these appear as
integration constants.

</DOC>
<DOC>
<DOCNO> 178767 </DOCNO>
Spatially inhomogeneous condensate in asymmetric nuclear matter


  We study the isospin singlet pairing in asymmetric nuclear matter with
nonzero total momentum of the condensate Cooper pairs. The quasiparticle
excitation spectrum is fourfold split compared to the usual BCS spectrum of the
symmetric, homogeneous matter. A twofold splitting of the spectrum into
separate branches is due to the finite momentum of the condensate, the isospin
asymmetry, or the finite quasiparticle lifetime. The coupling of the isospin
singlet and triplet paired states leads to further twofold splitting of each of
these branches. We solve the gap equation numerically in the isospin singlet
channel in the case where the pairing in the isospin triplet channel is
neglected and find nontrivial solutions with finite total momentum of the
pairs. The corresponding phase assumes a periodic spatial structure which
carries a isospin density wave at constant total number of particles. The phase
transition from the BCS to the inhomogeneous superconducting phase is found to
be first order and occurs when the density asymmetry is increased above 0.25.
The transition from the inhomogeneous superconducting to the unpaired normal
state is second order. The maximal values of the critical total momentum (in
units of the Fermi momentum) and the critical density asymmetry at which
condensate disappears are $P_c/p_F = 0.3$ and $\alpha_c = 0.41$. The possible
spatial forms of the ground state of the inhomogeneous superconducting phase
are briefly discussed.

</DOC>
<DOC>
<DOCNO> 13564 </DOCNO>
Theory of Strongly Correlated Electron Systems. III. Including


  In previous papers we showed that a division of the f-shell into two
subsystems gives a better understanding of cohesive properties as well the
general behavior of lanthanide systems. In this paper we present numerical
computations using the suggested method. We show that the picture is consistent
with most experimental data, e.g. the equilibrium volume and electronic
structure in general. Compared to standard energy band calculations, or to
calculations based on the self interaction correction and LDA+U, in the present
approach f-(non-f)-mixing interaction is decreased by spectral weights of the
many-body states of the f-ion are involved.

</DOC>
<DOC>
<DOCNO> 85022 </DOCNO>
On the Numerical Stability of the Einstein Equations


  We perform a von Neumann stability analysis on a common discretization of the
Einstein equations. The analysis is performed on two formulations of the
Einstein equations, namely, the standard ADM formulation and the
conformal-traceless (CT) formulation. The eigenvalues of the amplification
matrix are computed for flat space as well as for a highly nonlinear plane wave
exact solution. We find that for the flat space initial data, the condition for
stability is simply $\frac {\Delta t}{\Delta z} \leq 1$. However, a von Neumann
analysis for highly nonlinear plane wave initial data shows that the standard
ADM formulation is unconditionally unstable, while the conformal-traceless (CT)
formulation is stable for $0.25 \leq \frac {\Delta t}{\Delta z} < 1$.

</DOC>
<DOC>
<DOCNO> 101761 </DOCNO>
Quantum Groups and Von Neumann Theorem


  We discuss the $q$ deformation of Weyl-Heisenberg algebra in connection with
the von Neumann theorem in Quantum Mechanics. We show that the $q$-deformation
parameter labels the Weyl systems in Quantum Mechanics and the unitarily
inequivalent representations of the canonical commutation relations in Quantum
Field Theory.

</DOC>
<DOC>
<DOCNO> 13103 </DOCNO>
The superfluid phases of quark matter: Ginzburg-Landau theory and color


  We apply Ginzburg-Landau theory to determine BCS pairing in a
strongly-coupled uniform superfluid of three-flavor massless quarks in flavor
equilibrium. We elucidate the phase diagram near the critical temperature in
the space of the parameters characterizing the thermodynamic potential terms of
fourth order in the pairing gap. Within the color and flavor antisymmetric
channel with zero total angular momentum, the phase diagram contains an
isoscalar (IS) color-antitriplet phase and a color-flavor-locked (CFL) phase,
reached by a second order transition from the normal state, as well as states
reached by a first order transition. We complement the general Ginzburg-Landau
approach by deriving the high-density asymptotic form of the Ginzburg-Landau
free energy from the weak-coupling gap equation. The dynamically-screened,
long-range color magnetic interactions are taken into account in solving the
gap equation. We find that in the limit of weak coupling, the IS phase is less
favorable near the transition temperature than the CFL phase. In view of the
fact that deconfined quark matter must be color charge neutral, we incorporate
the constraint of overall color neutrality into the Ginzburg-Landau theory and
the gap equation. This constraint yields a disparity in the chemical potential
between colors and reduces the size of the gap, in the presence of the
anisotropy of the order parameters in color space. In comparison with the case
in which there are no chemical potential differences between colors and hence
the superfluid generally has nonzero net color charge, we find that while the
constraint of color neutrality has only negligible effects on the gap in the
weak coupling regime, it appreciably destabilizes the IS phase in the strong
coupling regime without affecting the CFL phase.

</DOC>
<DOC>
<DOCNO> 150897 </DOCNO>
Conformal Supergravity from the AdS/CFT Correspondence


  Construction of a five dimensional conformal supergravity (D=5 CSG) is
attempted by applying the AdS/CFT correspondence to the F(4) AdS supergravity
in six dimensions. As a first step, local transformation laws of D=5 CSG have
been established, from which the Weyl weights of the various fields in D=5 can
be predicted.

</DOC>
<DOC>
<DOCNO> 123054 </DOCNO>
Turbulent Velocity Structure in Molecular Clouds


  We compare velocity structure observed in the Polaris Flare molecular cloud
at scales ranging from 0.015 pc to 20 pc to the velocity structure of a suite
of simulations of supersonic hydrodynamic and MHD turbulence computed with the
ZEUS MHD code. We examine different methods of characterising the structure,
including a scanning-beam size-linewidth relation, structure functions,
velocity and velocity difference probability distribution functions (PDFs), and
the Delta-variance wavelet transform, and use them to compare models and
observations.
  The Delta-variance is most sensitive in detecting characteristic scales and
varying scaling laws, but is limited in the observational application by its
lack of intensity weighting. We compare the true velocity PDF in our models to
simulated observations of velocity centroids and average line profiles in
optically thin lines, and find that the line profiles reflect the true PDF
better.
  The observed velocity structure is consistent with supersonic turbulence
showing a complete spectrum from a driving scale larger than 10 pc, through an
inertial range, to a dissipation scale under 0.05 pc. Ambipolar diffusion could
explain this dissipation scale. Strong enough magnetic fields impose a clear
anisotropy on the velocity field, reducing the velocity variance in directions
perpendicular to the field.

</DOC>
<DOC>
<DOCNO> 117472 </DOCNO>
The Lake Baikal neutrino experiment: selected results


  We review the present status of the lake Baikal Neutrino Experiment and
present selected physical results gained with the consequetive stages of the
stepwise increasing detector: from NT-36 to NT-96. Results cover atmospheric
muons, neutrino events, very high energy neutrinos, search for neutrino events
from WIMP annihilation, search for magnetic monopoles and environmental
studies. We also describe an air Cherenkov array developed for the study of
angular resolution of NT-200.

</DOC>
<DOC>
<DOCNO> 122534 </DOCNO>
First Light Measurements with the XMM-Newton Reflection Grating


  The RS CVn binary system HR 1099 was extensively observed by the XMM-Newton
observatory in February 2000 as its first-light target. A total of 570 ks of
exposure time was accumulated with the Reflection Grating Spectrometers (RGS).
The integrated X-ray spectrum between 5-35 Angstrom is of unprecedented quality
and shows numerous features attributed to transitions of the elements C, N, O,
Ne, Mg, Si, S, Fe, and Ni. We perform an in-depth study of the elemental
composition of the average corona of this system, and find that the elemental
abundances strongly depend on the first ionisation potential (FIP) of the
elements. But different from the solar coronal case, we find an inverse FIP
effect, i.e., the abundances (relative to oxygen) increase with increasing FIP.
Possible scenarios, e.g., selective enrichment due to Ne-rich flare-like
events, are discussed.

</DOC>
<DOC>
<DOCNO> 117794 </DOCNO>
Detection of Stellar Spots from the Observations of Caustic-Crossing


  Recently, Heyrovsk\'y & Sasselov (1999) investigated the sensitivity of {\it
single-lens} gravitational microlensing event light curves to small spots and
found that during source transit events spots can cause deviations in
amplification larger than 2%, and thus be detectable. In this paper, we explore
the feasibility of spot detection from the observations of {\it
caustic-crossing binary-lens} microlensing events instead of single-lens
events. For this we investigate the sensitivity of binary-lens event light
curves to spots and compare it to that of single-lens events. From this
investigation, we find that during caustic crossings the fractional
amplification deviations of microlensing light curves from those of spotless
source events are equivalent to the deviations of single-lens events, implying
that spots can also be detected with a similar photometric precision to that
required for spot detection by observing single-lens events. We discuss the
relative advantages of observing caustic-crossing binary-lens events over the
observations of single-lens events in detecting stellar spots.

</DOC>
<DOC>
<DOCNO> 170176 </DOCNO>
Greenberger-Horne-Zeilinger nonlocality in phase space


  We show that the continuous-variable analogues to the multipartite entangled
Greenberger-Horne-Zeilinger states of qubits violate Bell-type inequalities
imposed by local realistic theories. Our results suggest that the degree of
nonlocality of these nonmaximally entangled continuous-variable states,
represented by the maximum violation, grows with increasing number of parties.
This growth does not appear to be exponentially large as for the maximally
entangled qubit states, but rather decreases for larger numbers of parties.

</DOC>
<DOC>
<DOCNO> 11202 </DOCNO>
Static and Dynamic Monte Carlo Simulations of Br Electrodeposition on


  We study the static and dynamic properties of bromine electrosorption onto
single-crystal silver (100) electrodes by Monte Carlo simulation. At room
temperature the system displays a second-order phase transition between a
low-coverage disordered phase at more negative electrode potentials and a
c(2x2) ordered phase with bromine coverage 1/2 at more positive potentials. We
explore the phase diagram and demonstrate that the broad shoulder observed in
room-temperature cyclic voltammograms is due to local fluctuations resembling
ordered phases with coverage 1/4 which exist in the model at much lower
temperatures. We construct a dynamic Monte Carlo algorithm using a thermally
activated stochastic barrier-hopping model for the microscopic dynamics. We use
this algorithm to study the phase ordering and disordering processes following
sudden potential steps between the disordered phase and the c(2x2) phase and to
study the sweep-rate dependence in simulated cyclic-voltammetry experiments.

</DOC>
<DOC>
<DOCNO> 101068 </DOCNO>
The dynamics around stable and unstable Hamiltonian relative equilibria


  For a symmetric Hamiltonian system on a symplectic manifold, lower bounds for
the number of relative equilibria surrounding stable and formally unstable
relative equilibria on nearby energy levels are given. Lower bounds for
previous merely existential results of Lerman and Tokieda on relative periodic
orbits are obtained as corollaries of the presented techniques, as well as an
improvement of a previous result of Montaldi, Roberts, and Stewart, on the
existence of periodic orbits around a symmetric Hamiltonian equilibrium,
already obtained by Bartsch.

</DOC>
<DOC>
<DOCNO> 151353 </DOCNO>
The Godbillon-Vey class, invariants of manifolds and linearised M-Theory


  We apply the Godbillon-Vey class to compute the transition amplitudes between
some non-commutative solitons in M-Theory; our context is that of
Connes-Douglas-Schwarz where they considered compactifications of matrix models
on noncommutative tori. Two important consequences follow: we describe a new
normalisation for the Abelian Chern-Simons theory using symplectic 4-manifolds
as providing cobordisms for tight contact 3-manifolds and we construct a new(?)
invariant for 3-manifolds. Moreover we modify the topological Lagrangian
density suggested for M-Theory in a previous article to a \textsl{quadratic}
one using the fact that the \emph{functor of immersions is a linearisation (or
``the differential'') of the functor of embeddings}

</DOC>
<DOC>
<DOCNO> 101749 </DOCNO>
Translational and Rotational Properties of Antisymmetric Tensor Fields


  Recently, several discussions on the possible observability of 4-vector
potential have been published in literature. Furthermore, several authors
recently claimed existence of the helicity=0 electromagnetic field. We
re-examine the theory of antisymmetric tensor field and 4-vector potentials. We
study the massless limits too. In fact, a theoretical motivation for this
venture is old papers of Ogievetskii and Polubarinov, Hayashi, and Kalb and
Ramond, which are widely accepted by physics community. This paper is based on
two poster presentations ``About the Longitudinal Nature of the Antisymmetric
Tensor Field after Quantization" and ``Normalization and m->0 Limit of the
Proca Theory" at the Workshop "Lorentz Group, CPT and Neutrinos" (Zacatecas,
Mexico, June 23-26, 1999).

</DOC>
<DOC>
<DOCNO> 100610 </DOCNO>
On the Quantum Quarter Plane and the Real Quantum Plane


  Suppose q is a complex number of modulus one and different from 1,-1. Let
O(R^2_q) be the *-algebra with two hermitean generators x and y satisfying the
relation xy=qyx. Using operator representations of the *-algebra O(R^2_q) on
Hilbert space and the Weyl calculus of pseudodifferential operators we
construct *-algebras of ``functions'' on the quantum quarter plane R^{++}_q and
on the real quantum plane R^2_q which are left module *-algebras for the Hopf
*-algebra U_q(gl_2(R)). We define a family h_k, k\in Z^2, of covariant positive
linear functionals on these *-algebras and study the actions of the *-algebras
O(R^2_q) and U_q(gl_2(R)) on the associated Hilbert spaces. Quantum analogs of
the partial Fourier transforms and the Fourier transform are found. A
differential calculus on the ``function'' *-algebras is also developed and
investigated.

</DOC>
<DOC>
<DOCNO> 99477 </DOCNO>
Quantum Diffusions and Appell Systems


  Within the algebraic framework of Hopf algebras, random walks and associated
diffusion equations (master equations) are constructed and studied for two
basic operator algebras of Quantum Mechanics i.e the Heisenberg-Weyl algebra
(hw) and its q-deformed version hw_q. This is done by means of functionals
determined by the associated coherent state density operators. The ensuing
master equations admit solutions given by hw and hw_q-valued Appell systems.

</DOC>
<DOC>
<DOCNO> 170376 </DOCNO>
Quantum reference systems: reconciling locality with quantum mechanics


  The status of locality in quantum mechanics is analyzed from a nonstandard
point of view. It is assumed that quantum states are relative, they depend on
and are defined with respect to some bigger physical system which contains the
former system as a subsystem. Hence, the bigger system acts as a reference
system. It is shown that quantum mechanics can be reformulated in accordance
with this new physical assumption. There is an important consequence of this
dependence: states may not be comparable, i.e., they cannot be checked by
suitable measurements simultaneously. This special circumstance is fully
reflected mathematically by the theory. Especially, it is shown that certain
joint probabilities (or the corresponding combined events) which play a vital
role in any proof of Bell's theorem do not exist. The conclusion is that the
principle of locality is fully valid in quantum mechanics, and one has to give
up instead of locality an intuitively natural-looking feature of realism,
namely, the comparability of existing states.

</DOC>
<DOC>
<DOCNO> 120152 </DOCNO>
A spiral structure in the disk of EX Draconis on the rise to outburst


  We report on the R-band eclipse mapping analysis of high-speed photometry of
the dwarf nova EX Dra on the rise to the maximum of the November 1995 outburst.
The eclipse map shows a one-armed spiral structure of ~180 degrees in azimuth,
extending in radius from R ~0.2 to 0.43 R_{L1} (where R_{L1} is the distance
from the disk center to the inner Lagrangian point), that contributes about 22
per cent of the total flux of the eclipse map. The spiral structure is
stationary in a reference frame co-rotating with the binary and is stable for a
timescale of at least 5 binary orbits. The comparison of the eclipse maps on
the rise and in quiescence suggests that the outbursts of EX Dra may be driven
by episodes of enhanced mass-transfer from the secondary star. Possible
explanations for the nature of the spiral structure are discussed.

</DOC>
<DOC>
<DOCNO> 123094 </DOCNO>
Gamma Rays from Molecular Clouds


  I discuss the spectral features of pi-0 decay gamma-radiation from
clouds/targets located in proximity of relatively young proton accelerators,
and speculate that such ``accelerator+target'' systems in our Galaxy can be
responsible for a subset of unidentified EGRET sources. Also, I argue that the
recent observations of high energy gamma-rays from the Orion complex contain
evidence that the level of the ``sea'' of galactic cosmic rays may differ
significantly from the flux and the spectrum of local (directly detected)
particles.

</DOC>
<DOC>
<DOCNO> 39650 </DOCNO>
Structure Functions in Deep Inelastic Lepton-Nucleon Scattering


  Latest results on structure functions, as available at the Lepton-Photon
Symposium 1999, are presented. This report focusses on three experimental
areas: new structure function measurements, in particular from HERA at low x
and high Q2; results on light and heavy flavour densities; determinations of
the gluon distribution and of alpha_s. As the talk was delivered at a historic
moment and place, a few remarks were added recalling the exciting past and
looking into the promising future of deep inelastic scattering.

</DOC>
<DOC>
<DOCNO> 8111 </DOCNO>
Spin-Peierls instability in the spin-1/2 transverse XX chain with


  We calculate exactly the density of magnon states of the regularly
alternating spin-1/2 XX chain with Dzyaloshinskii-Moriya interaction. The
obtained results permit us to examine the stability of the chain with respect
to spin-Peierls dimerization. We found that depending on the dependences of
Dzyaloshinskii-Moriya interaction on distortion amplitude it may act either in
favour of the dimerization or against the dimerization.

</DOC>
<DOC>
<DOCNO> 121547 </DOCNO>
Constraints on the Inner Mass Profiles of Lensing Galaxies from Missing


  Most gravitational lens systems consist of two or four observable images. The
absence of detectable odd images allows us to place a lower limit on the
power-law slope of the inner mass profile of lensing galaxies. Using a sample
of six two-image radio-loud lens systems and assuming a singular power-law
surface density (Sigma proportional to r^{-beta}) for the inner several kpc of
the mass distribution, we find that there is less than a 10% probability that
the data are consistent with profile slopes beta < 0.80. Furthermore,
individual mass modeling yields beta > 0.85 for B0739+366 and beta > 0.91 for
B1030+074. Modeling central black holes as additional point masses changes the
constraints in these systems to beta > 0.84 and beta > 0.83, respectively. The
inner mass profiles of lensing galaxies are therefore not much shallower than
isothermal.

</DOC>
<DOC>
<DOCNO> 122835 </DOCNO>
Singular Isothermal Disks and the Formation of Multiple Stars


  A crucial missing ingredient in previous theoretical studies of fragmentation
is the inclusion of dynamically important levels of magnetic fields. As a
minimal model for a candidate presursor to the formation of binary and multiple
stars, we therefore consider the equilibrium configuration of isopedically
magnetized, scale-free, singular isothermal disks, without the assumption of
axial symmetry. We find that lopsided (M=1) configurations exist at any
dimensionless rotation rate, including zero. Multiple-lobed (M = 2, 3, 4, ...)
configurations bifurcate from an underlying axisymmetric sequence at
progressively higher dimensionless rates of rotation, but such nonaxisymmetric
sequences always terminate in shockwaves before they have a chance to fission
into separate bodies. We advance the hypothesis that binary and multiple
star-formation from smooth (i.e., not highly turbulent) starting states that
are supercritical but in unstable mechanical balance requires the rapid (i.e.,
dynamical) loss of magnetic flux at some stage of the ensuing gravitational
collapse.

</DOC>
<DOC>
<DOCNO> 101238 </DOCNO>
A logical description for perfect measurements


  We reconsider the description for property transitions due to perfect
measurements, viewing them as a special case of general transitions that are
due to an externally imposed change. We propose a corresponding syntax
involving operational quantum logic and a fragment of non-commutative linear
logic.

</DOC>
<DOC>
<DOCNO> 83107 </DOCNO>
A flexible framework for defeasible logics


  Logics for knowledge representation suffer from over-specialization: while
each logic may provide an ideal representation formalism for some problems, it
is less than optimal for others. A solution to this problem is to choose from
several logics and, when necessary, combine the representations. In general,
such an approach results in a very difficult problem of combination. However,
if we can choose the logics from a uniform framework then the problem of
combining them is greatly simplified. In this paper, we develop such a
framework for defeasible logics. It supports all defeasible logics that satisfy
a strong negation principle. We use logic meta-programs as the basis for the
framework.

</DOC>
<DOC>
<DOCNO> 11356 </DOCNO>
Dynamic Scaling in One-Dimensional Cluster-Cluster Aggregation


  We study the dynamic scaling properties of an aggregation model in which
particles obey both diffusive and driven ballistic dynamics. The diffusion
constant and the velocity of a cluster of size $s$ follow $D(s) \sim s^\gamma$
and $v(s) \sim s^\delta$, respectively. We determine the dynamic exponent and
the phase diagram for the asymptotic aggregation behavior in one dimension in
the presence of mixed dynamics. The asymptotic dynamics is dominated by the
process that has the largest dynamic exponent with a crossover that is located
at $\delta = \gamma - 1$. The cluster size distributions scale similarly in all
cases but the scaling function depends continuously on $\gamma$ and $\delta$.
For the purely diffusive case the scaling function has a transition from
exponential to algebraic behavior at small argument values as $\gamma$ changes
sign whereas in the drift dominated case the scaling function decays always
exponentially.

</DOC>
<DOC>
<DOCNO> 70952 </DOCNO>
Bridging the mass gaps at A=5 and A=8 in nucleosynthesis


  In nucleosynthesis three possible paths are known to bridge the mass gaps at
A=5 and A=8. The primary path producing the bulk of the carbon in our Universe
proceeds via the triple-alpha process He4(2alpha,gamma)C12. This process takes
place in helium-burning of red giant stars. We show that outside a narrow
window of about 0.5% of the strength or range of the strong force, the stellar
production of carbon or oxygen through the triple-alpha process is reduced by
factors of 30 to 1000. Outside this small window the creation of carbon or
oxygen and therefore also carbon-based life in the universe is strongly
disfavored. The anthropically allowed strengths of the strong force also give
severe constraints for the sum of the light quark masses as well as the Higgs
vacuum expectation value and mass parameter at the 1% level.

</DOC>
<DOC>
<DOCNO> 68777 </DOCNO>
Warped Compactifications in M and F Theory


  We study M and F theory compactifications on Calabi-Yau four-folds in the
presence of non-trivial background flux. The geometry is warped and belongs to
the class of p-brane metrics. We solve for the explicit warp factor in the
orbifold limit of these compactifications, compare our results to some of the
more familiar recently studied warped scenarios, and discuss the effects on the
low-energy theory. As the warp factor is generated solely by backreaction, we
may use topological arguments to determine the massless spectrum. We perform
the computation for the case where the four-fold equals K3 \times K3.

</DOC>
<DOC>
<DOCNO> 122312 </DOCNO>
Long-Term RXTE Monitoring of the Anomalous X-ray Pulsar 1E 1048.1-5937


  We report on long-term monitoring of the anomalous X-ray pulsar (AXP) 1E
1048.1-5937 using the Rossi X-ray Timing Explorer (RXTE). The timing behavior
of this pulsar is different from that of other AXPs being monitored with RXTE.
In particular, we show that the pulsar shows significant deviations from simple
spin-down such that phase-coherent timing has not been possible over time spans
longer than a few months. We find that the deviations from simple spin down are
not consistent with single "glitch" type events, nor are they consistent with
radiative precession. We show that in spite of the rotational irregularities,
the pulsar exhibits neither pulse profile changes nor large pulsed flux
variations. We discuss the implications of our results for AXP models. In the
context of the magnetar model, we suggest that 1E 1048.1-5937 may be a
transition object between the soft gamma-ray repeater and AXP populations, and
the AXP most likely to one day undergo an outburst.

</DOC>
<DOC>
<DOCNO> 101796 </DOCNO>
Symmetric groups and the cup product on the cohomology of Hilbert


  The integral cohomology ring of the Hilbert scheme of n-tuples on the affine
plane is shown to be isomorphic to the graded ring associated to a filtration
of the ring of integral class functions on the symmetric group.

</DOC>
<DOC>
<DOCNO> 101783 </DOCNO>
Finding topology in a factory: configuration spaces


  This expository article describes applications of topological configuration
spaces to the control of robotic systems. In particular, we review recent work
by the authors on configuration spaces of graphs. These are lovely spaces: we
show for example that the configuration space of two points on the complete
graph of five vertices is a closed orientable surface of genus six.

</DOC>
<DOC>
<DOCNO> 119831 </DOCNO>
X-ray spectral features from GRBs: Predictions of progenitor models


  We investigate the potentially observable prompt or delayed X-ray spectral
features from the currently popular gamma-ray burst (GRB) models. During the
evolution of many GRB progenitors, a disk around the central GRB source is
produced. Shock heating as the GRB ejecta collide with the disk may produce
observable X-ray features. We first summarize predictions deduced from previous
calculations which invoke photoionization and relativistic blast waves. We then
calculate the quasi-thermal X-ray line features produced assuming the ejecta
are nonrelativistic (which is more likely for the disk interactions of many GRB
models). In the framework of the Hypernova/Collapsar model, delayed (a few days
- several months after the GRB) bursts of line-dominated, thermal X-ray
emission may be expected. The He-merger scenario predicts similar X-ray
emission line bursts <~ a few days after the GRB. These X-ray signatures should
be observable with Chandra and XMM-Newton out to at least z ~ 1. Weak emission
line features <~ a few days after the GRB may also result from the supranova
GRB scenario. In all three cases, significant X-ray absorption features, in
particular during the prompt GRB phase, are expected. No significant X-ray
spectral features might result from compact-object binary mergers.

</DOC>
<DOC>
<DOCNO> 118853 </DOCNO>
GI2T/REGAIN spectro-interferometry with a new infrared beam combiner


  We have built an infrared beam combiner for the GI2T/REGAIN interferometer of
the Observatoire de la Cote d'Azur. The beam combiner allows us to record
spectrally dispersed Michelson interference fringes in the near-infrared J-, H-
or K-bands. The beam combiner has the advantage that Michelson interferograms
can simultaneously be recorded in about 128 different spectral channels. The
tilt of the spectrally dispersed fringes is a measure of the instantaneous
optical path difference. We present the optical design of the beam combiner and
GI2T/REGAIN observations of the Mira star R Cas with this beam combiner in the
spectral range of 2.00 micron - 2.18 micron (observations on 22 and 25 August
1999; variability phase 0.08; V-magnitude approx. 6; seven baselines between
12m and 24m; reference stars Vega and Beta Peg). The spectrograph of the beam
combiner consists of an anamorphotic cylindrical lens system, an image plane
slit, and a grism. A system of digital signal processors calculates the
ensemble average power spectrum of the spectrally dispersed Michelson
interferograms and the instantaneous optical path difference error in real
time. From the observed R Cas visibilities at baselines 12.0m, 13.8m and 13.9m,
a 2.1 micron uniform-disk diameter of 25.3mas +/-3.3mas was derived. The
unusually high visibility values at baselines >16m show that the stellar
surface of R Cas is more complex than previously assumed. The visibility values
at baselines >16m can be explained by high-contrast surface structure on the
stellar surface of R Cas or other types of unexpected center-to-limb
variations. The R Cas observations were compared with theoretical Mira star
models yielding a linear Rosseland radius of 276Rsun +/-66Rsun and an effective
temperature of 2685K+/-238K for R Cas at phase 0.08.

</DOC>
<DOC>
<DOCNO> 70333 </DOCNO>
Looking for a varying $\alpha$ in the Cosmic Microwave Background


  We perform a likelihood analysis of the recently released BOOMERanG and
MAXIMA data, allowing for the possibility of a time-varying fine-structure
constant. We find that in general this data prefers a value of $\alpha$ that
was smaller in the past (which is in agreement with measurements of $\alpha$
from quasar observations). However, there are some interesting degeneracies in
the problem which imply that strong statements about $\alpha$ can not be made
using this method until independent accurate determinations of $\Omega_b h^2$
and $H_0$ are available.
  We also show that a preferred lower value of $\alpha$ comes mainly from the
data points around the first Doppler peak, whereas the main effect of the
high-$\ell$ data points is to increase the preferred value for $\Omega_b h^2$
(while also tightening the constraints on $\Omega_0$ and $H_0$). We comment on
some implications of our results.

</DOC>
<DOC>
<DOCNO> 71921 </DOCNO>
Non-Oscillation Searches of Neutrino Mass in the Age of Oscillations


  We focus on the implications of the oscillations for the shape of nuclear
beta-spectrum (=direct search for nu mass). This is of interest because of the
existing bound, m_(nu_e)<2.2 eV, that could improve by one order of magnitude
with future experiments. We stress important connections with the results of
Liquid Scintillator Neutrino Detector, nu_e disappearance experiments,
supernova neutrinos and neutrinoless double beta decay.

</DOC>
<DOC>
<DOCNO> 100842 </DOCNO>
On representations of integers by indefinite ternary quadratic forms


  Let $f$ be an indefinite ternary quadratic form, and let $q$ be an integer
such that $-q det(f)$ is not a square. Let $N(T,f,q)$ denote the number of
integral solutions of the equation $f(x)=q$ where $x$ lies in the ball of
radius $T$ centered at the origin. We are interested in the asymptotic behavior
of $N(T,f,q)$ as $T$ tends to infinity.
  We deduce from the results of our joint paper with Z. Rudnick that $N(T,f,q)$
grows like cE(T,f,q)$ as $T$ tends to infinity, where $E(T,f,q)$ is the
Hardy-Littlewood expectation (the product of local densities) and $0 \le c \le
2$. We give examples of $f$ and $q$ such that $c$ takes the values 0, 1, 2.

</DOC>
<DOC>
<DOCNO> 71431 </DOCNO>
High-Energy-Physics Event Generation with PYTHIA 6.1


  PYTHIA version 6 represents a merger of the PYTHIA 5, JETSET 7 and SPYTHIA
programs, with many improvements. It can be used to generate
high-energy-physics `events', i.e. sets of outgoing particles produced in the
interactions between two incoming particles. The objective is to provide as
accurate as possible a representation of event properties in a wide range of
reactions. The underlying physics is not understood well enough to give an
exact description; the programs therefore contain a combination of analytical
results and various models. The emphasis in this article is on new aspects, but
a few words of general introduction are included. Further documentation is
available on the web.

</DOC>
<DOC>
<DOCNO> 80615 </DOCNO>
Recursive sampling simulations of 3D gravity coupled to scalar fermions


  We study numerically the phase structure of a model of 3D gravity interacting
with scalar fermions. We measure the 3D counterpart of the "string"
susceptibility exponent as a function of the inverse Newton coupling $\alpha$.
We show that there are two phases separated by a critical point around
$\alpha_c \simeq 2$. The numerical results support the hypothesis that the
phase structures of 3D and 2D simplicial gravity are qualitatively similar, the
inverse Newton coupling in 3D playing the role of the central charge of matter
in 2D.

</DOC>
<DOC>
<DOCNO> 84190 </DOCNO>
Gravitational waves from inspiralling compact binaries with magnetic


  We investigate the effects of the magnetic dipole-dipole coupling and the
electromagnetic radiation on the frequency evolution of gravitational waves
from inspiralling binary neutron stars with magnetic dipole moments. This study
is motivated by the discovery of the superstrongly magnetized neutron stars,
i.e., magnetar. We derive the contributions of the magnetic fields to the
accumulated cycles in gravitational waves as $N_{mag} \sim 6 \times 10^{-3}
(H/10^{16}{\rm G})^{2}$, where $H$ denotes the strength of the polar magnetic
fields of each neutron star in the binary system. It is found that the effects
of the magnetic fields will be negligible for the detection and the parameter
estimation of gravitational waves, if the upper limit for magnetic fields of
neutron stars are less than $\sim 10^{16}$G, which is the maximum magnetic
field observed in the soft gamma repeaters and the anomalous X-ray pulsars up
to date. We also discuss the implications of electromagnetic radiation from the
inspiralling binary neutron stars for the precursory X-ray emission prior to
the gamma ray burst observed by the Ginga satellite.

</DOC>
<DOC>
<DOCNO> 101988 </DOCNO>
Another Set of Sequences, Sub-Sequences, and Sequences of Sequences


  In this paper 101 new integer sequences, sub-sequences, and sequences of
sequences, together with related unsolved problems and conjectures, are
presented. Also, definitions, examples, solved or open questions, and
references for each sequence are given.

</DOC>
<DOC>
<DOCNO> 150438 </DOCNO>
Actions for Biconformal Matter


  We extend 2n-dim biconformal gauge theory by including Lorentz-scalar matter
fields of arbitrary conformal weight. For a massless scalar field of conformal
weight zero in a torsion-free biconformal geometry, the solution is determined
by the Einstein equation on an n-dim submanifold, with the stress-energy tensor
of the scalar field as source. The matter field satisfies the n-dim
Klein-Gordon equation.

</DOC>
<DOC>
<DOCNO> 11423 </DOCNO>
Crystallization of hard spheres under gravity


  We present a simple argument to account for crystallization of hard spheres
under the action of a gravitational field. The paper attempts to bridge the gap
between two communities of scientists, one working on granular materials and
the other on inhomogeneous liquid state theory.

</DOC>
<DOC>
<DOCNO> 102670 </DOCNO>
Rational curves on Grassmannians: systems theory, reality, and


  We discuss a particular problem of enumerating rational curves on a
Grassmannian from several perspectives, including systems theory, real
enumerative geometry, and symbolic computation. We also present a new
transversality result, showing this problem is enumerative in all
characteristics.
  While it is well-known how this enumerative problem arose in mathematical
physics and also its importance to the development of quantum cohomology, it is
less known how it arose independently in mathematical systems theory. We
describe this second story.

</DOC>
<DOC>
<DOCNO> 118765 </DOCNO>
The artificial night sky brightness mapped from DMSP Operational


  We present a method to map the artificial sky brightness across large
territories in astronomical photometric bands with a resolution of
approximately 1 km. This is useful to quantify the situation of night sky
pollution, to recognize potential astronomical sites and to allow future
monitoring of trends. The artificial sky brightness present in the chosen
direction at a given position on the Earth's surface is obtained by the
integration of the contributions produced by every surface area in the
surrounding. Each contribution is computed based on detailed models for the
propagation in the atmosphere of the upward light flux emitted by the area. The
light flux is measured with top of atmosphere radiometric observations made by
the Defense Meteorological Satellite Program (DMSP) Operational Linescan
System.
  We applied the described method to Europe obtaining the maps of artificial
sky brightness in V and B bands.

</DOC>
<DOC>
<DOCNO> 13389 </DOCNO>
Image charges revisited: a closed form solution


  We demonstrate that the corrections to the classical Kelvin image theory due
to finite electron screening length $\lambda$, recently discussed by Roulet and
Saint Jean, Am. J. Phys. 68(4) 319, is amenable to an exact closed form
solution in terms of an integral involving Bessel functions. An improper choice
of boundary conditions is rectified as well, enabling also a complete solution
for all potentials - both inside and outside the metal surface.

</DOC>
<DOC>
<DOCNO> 174582 </DOCNO>
Evidence for a Soft Nuclear Equation-of-State from Kaon Production in


  The production of pions and kaons has been measured in Au+Au collisions at
beam energies from 0.6 to 1.5 AGeV with the Kaon Spectrometer at SIS/GSI. The
K+ meson multiplicity per nucleon is enhanced in Au+Au collisions by factors up
to 6 relative to C+C reactions whereas the corresponding pion ratio is reduced.
The ratio of the K+ meson excitation functions for Au+Au and C+C collisions
increases with decreasing beam energy. This behavior is expected for a soft
nuclear equation-of-state.

</DOC>
<DOC>
<DOCNO> 7810 </DOCNO>
On the electronic structure of CaCuO2 and SrCuO2


  Recent electronic structure calculations for the prototypical lowdimensional
cuprate compounds CaCuO2 ans SrCuO2 performed by Wu et. al. (J. Phys.: Condens.
Matter v. 11 p.4637 (1999))are critically reconsidered, applying high precision
full-potential bandstructure methods. It is shown that the bandstructure
calculations presented by the authors contain several important
inconsistencies, which make their main conclusions highly questionable.

</DOC>
<DOC>
<DOCNO> 102332 </DOCNO>
Induced representations of affine Hecke algebras and canonical bases of


  A criterion of irreducibility for induction products of evaluation modules of
type A affine Hecke algebras is given. It is derived from multiplicative
properties of the canonical basis of a quantum deformation of the
Bernstein-Zelevinsky ring.

</DOC>
<DOC>
<DOCNO> 100673 </DOCNO>
Homotopy field theory in dimension 3 and crossed group-categories


  A 3-dimensional homotopy quantum field theory (HQFT) can be described as a
TQFT for surfaces and 3-cobordisms endowed with homotopy classes of maps into a
given space. For a group $\pi$, we introduce a notion of a modular crossed
$\pi$-category and show that such a category gives rise to a 3-dimensional HQFT
with target space $K(\pi,1)$. This includes numerical invariants of
3-dimensional $\pi$-manifolds and a 2-dimensional homotopy modular functor. We
also introduce and discuss a parallel notion of a quasitriangular crossed Hopf
$\pi$-coalgebra.

</DOC>
<DOC>
<DOCNO> 122842 </DOCNO>
Cosmological Parameters: do we already know the final answer ?


  Some of the arguments which support the strong concensus for an $\Omega_o$ =
0.3, $\lambda_o$ = 0.7 model are reexamined. Corrections for Malmquist bias,
local flow and metallicity suggest a revised value for $H_o$ of 63 $\pm$ 6
km/s/Mpc, improving the age problems for an $\Omega_o$ = 1 universe. The latest
CMB results may require a high baryon density and hence new physics, for
example a strong lepton asymmetry. Difficulties for the $\Omega_o$ = 1 model
with cluster evolution, the baryon content of clusters, and the evidence from
Type Ia supernovae favouring low $\Omega_o$, $\Lambda > 0$ models, are
discussed critically.

</DOC>
<DOC>
<DOCNO> 121768 </DOCNO>
Formation and evolution of a 0.242 Msun helium white dwarf in presence


  A 0.242 Msun object that finally becomes a helium white dwarf is evolved from
Roche lobe detachment down to very low luminosities. In doing so, we employ our
stellar code to which we have added a set of routines that compute the effects
due to gravitational settling, and chemical and thermal diffusion. Initial
model is constructed by abstracting mass to a 1 Msun red giant branch model up
to the moment at which the model begins to evolve bluewards. We find that
element diffusion introduces noticeable changes in the internal structure of
the star. In particular, models undergo three thermonuclear flashes instead of
one flash as we found with the standard treatment. This fact has a large impact
on the total mass fraction of hydrogen left in the star at entering the final
cooling track. As a result, at late stages of evolution models with diffusion
are characterized by a much smaller nuclear energy release, and they evolve
significantly faster compared to those found with the standard treatment.
  We find that models in which diffusion is considered predict evolutionary
ages for the white dwarf companion to the millisecond pulsar PSR B1855+09 in
good agreement with the spin-down age of the pulsar.

</DOC>
<DOC>
<DOCNO> 69137 </DOCNO>
Renormalisation effects of neutrino masses and interactions


  1. Data and implications. 2. Neutrino threshold effects. 3. Renormalisation
of the neutrino mass operator and stability properties of neutrino textures. 4.
Neutrino thresholds effects and Yukawa unification. 5. Renormalisation-induced
lepton-flavour-violating processes from non-zero neutrino masses. 6. Summary.

</DOC>
<DOC>
<DOCNO> 11215 </DOCNO>
X-ray magnetic circular dichroism spectra on the superparamagnetic


  The first X-ray magnetic circular dichroism (XMCD) spectra on the title
compounds are presented. In Mn12 the Mn(III) and Mn(IV) contributions are
clearly apparent and evidence the opposite spin arrangement of the two ions.
For Fe8 the typical two peak structure of Fe(III) compounds is found.
Quantitative analysis yielded for both compounds a negligible <Lz>. This is the
first direct experimental evidence of the quenching of the angular momentum in
these systems. For Fe8 we found <Sz>=1.14 in mB units per Fe atom, in
reasonable agreement with the S=10 ground state assumed for in this system.

</DOC>
<DOC>
<DOCNO> 102010 </DOCNO>
The Based Ring of Two-Sided Cells of Affine Weyl Groups of Type $\tilde


  In this paper we prove Lusztig's conjecture on based ring for an affine Weyl
group of type $\tilde A_{n-1}$.

</DOC>
<DOC>
<DOCNO> 152379 </DOCNO>
Quantum mechanics on the noncommutative plane and sphere


  We consider the quantum mechanics of a particle on a noncommutative plane.
The case of a charged particle in a magnetic field (the Landau problem) with a
harmonic oscillator potential is solved. There is a critical point, where the
density of states becomes infinite, for the value of the magnetic field equal
to the inverse of the noncommutativity parameter. The Landau problem on the
noncommutative two-sphere is also solved and compared to the plane problem.

</DOC>
<DOC>
<DOCNO> 13982 </DOCNO>
Polytetrahedral Clusters


  By studying the structures of clusters bound by a model potential that
favours polytetrahedral order, we find a previously unknown series of `magic
numbers' (i.e. sizes of special stability) whose polytetrahedral structures are
characterized by disclination networks that are analogous to hydrocarbons.

</DOC>
<DOC>
<DOCNO> 116527 </DOCNO>
Test Results on the Silicon Pixel Detector for the TTF-FEL Beam


  Test measurements on the silicon pixel detector for the beam trajectory
monitor at the free electron laser of the TESLA test facility are presented. To
determine the electronic noise of detector and read-out and to calibrate the
signal amplitude of different pixels the 6 keV photons of the manganese K line
are used. Two different methods determine the spatial accuracy of the detector:
In one setup a laser beam is focused to a straight line and moved across the
pixel structure. In the other the detector is scanned using a low-intensity
electron beam of an electron microscope. Both methods show that the symmetry
axis of the detector defines a straight line within 0.4 microns. The
sensitivity of the detector to low energy X-rays is measured using a vacuum
ultraviolet beam at the synchrotron light source HASYLAB. Additionally, the
electron microscope is used to study the radiation hardness of the detector.

</DOC>
<DOC>
<DOCNO> 150736 </DOCNO>
Canonical transformations and soldering


  We show that the recently developed soldering formalism in the Lagrangian
approach and canonical transformations in the Hamiltonian approach are
complementary. The examples of gauged chiral bosons in two dimensions and
self-dual models in three dimensions are discussed in details.

</DOC>
<DOC>
<DOCNO> 11123 </DOCNO>
Shubnikov-de Haas oscillations near the metal-insulator transition in a


  We have studied Shubnikov-de Haas oscillations in a two-dimensional electron
system in silicon at low electron densities. Near the metal-insulator
transition, only "spin" minima of the resistance at Landau-level filling
factors 2, 6, 10, and 14 are seen, while the "cyclotron" minima at filling
factors 4, 8, and 12 disappear. A simple explanation of the observed behavior
requires a giant enhancement of the spin splitting near the metal-insulator
transition.

</DOC>
<DOC>
<DOCNO> 151818 </DOCNO>
Weak binding limit and non zero angular momentum states in Light-Front


  We show some results concerning the weak binding limit for J=0 states --
which turn out to strongly differ from the non relativistic case -- together
with the construction of non zero angular momentum states. The calculation of
such states in the Light-Front Dynamics (LFD) framework has some peculiarities
which are absent in other approaches. They are related to the fact that the
rotation generators contain interaction. We present here the construction of
non zero angular momentum states in LFD and show how it leads to a restoration
of rotational invariance. For this purpose, the use of Light-Front Dynamics in
its explicitly covariant formulation is of crucial importance since the
dependence of the wave function on the light-front plane is explicitly
parametrized.

</DOC>
<DOC>
<DOCNO> 151255 </DOCNO>
Alternative approaches to the Casalbuoni-Brink-Schwarz Superparticle


  Wigner's method of induced representations is applied to the N=1
super-Poincare group, and by using a state corresponding to the basic vector of
the little group as a Clifford vacuum we show that the spin operator of a
supersymmetric point particle obeys Wigner's constraints. As dynamical
variables for the particle we use canonical coordinates on the symmetry group
manifold. The physical phase space is then constructed using a vielbein
formalism. We find that the Casalbuoni-Brink-Schwarz superparticle appears as a
special case of our general construction. Finally, the theory is reformulated
as a gauge theory where the gauge freedom corresponds to the choice of spin
constraints or, equivalently, the free choice of relativistic center of mass.
In a special case the gauge symmetry reduces to the well known kappa-symmetry.

</DOC>
<DOC>
<DOCNO> 101157 </DOCNO>
Some Results on the Janowski's Starlike Functions of Complex Order


  The purpose of this paper is to give exact value of the radius of
starlikeness and distortion theorem, Koebe domain for the class of Janowski's
starlike functions of complex order. We note that the class of Janowski's
starlike functions of complex order contain many interesting subclasses of
univalent functions.

</DOC>
<DOC>
<DOCNO> 99822 </DOCNO>
Poisson bracket, deformed bracket and gauge group actions in Kontsevich


  We express the difference between Poisson bracket and deformed bracket for
Kontsevich deformation quantization on any Poisson manifold by means of second
derivative of the formality quasi-isomorphism. The counterpart on star products
of the action of formal diffeomorphisms on Poisson formal bivector fields is
also investigated.

</DOC>
<DOC>
<DOCNO> 120046 </DOCNO>
Primordial Gaussian Fluctuations from Cosmic Defects


  We extend our recent work on ``two-metric'' theories of gravity by showing
how in such models cosmic defects can produce a spectrum of primordial Gaussian
density perturbations. This will happen when the speed characterising the decay
products of the defect network is much larger than the speed characterising
gravity and all standard model particles. This model will exactly mimic all the
standard predictions of inflationary models, and the only way of distinguishing
the two will be via the detection of the decay products of the network.

</DOC>
<DOC>
<DOCNO> 85043 </DOCNO>
Loop Quantum Gravity and Asymptotically Flat Spaces


  After motivating why the study of asymptotically flat spaces is important in
loop quantum gravity, we review the extension of the standard framework of this
theory to the asymptotically flat sector based on the GNS construction. In
particular, we provide a general procedure for constructing new Hilbert spaces
for loop quantum gravity on non-compact spatial manifolds. States in these
Hilbert spaces can be interpreted as describing fluctuations around fiducial
fixed backgrounds. When the backgrounds are chosen to approximate classical
asymptotically flat 3-geometries this gives a natural framework in which to
discuss physical applications of loop quantum gravity, especially its
semi-classical limit. We present three general proposals for the construction
of suitable backgrounds, including one approach that can lead to quantum
gravity on anti-DeSitter space as described by the Chern-Simons state.

</DOC>
<DOC>
<DOCNO> 12192 </DOCNO>
Extremal driving as a mechanism for generating long-term memory


  It is argued that systems whose elements are renewed according to an extremal
criterion can generally be expected to exhibit long-term memory. This is
verified for the minimal extremally driven model, which is first defined and
then solved for all system sizes N\geq2 and times t\geq0, yielding exact
expressions for the persistence R(t)=[1+t/(N-1)]^{-1} and the two-time
correlation function C(t_{\rm w}+t,t_{\rm w})=(1-1/N)(N+t_{\rm w})/(N+t_{\rm
w}+t-1). The existence of long-term memory is inferred from the scaling of
C(t_{\rm w}+t,t_{\rm w})\sim f(t/t_{\rm w}), denoting {\em aging}. Finally, we
suggest ways of investigating the robustness of this mechanism when competing
processes are present.

</DOC>
<DOC>
<DOCNO> 13382 </DOCNO>
Intermixture of extended edge and localized bulk energy levels in


  We study the spectrum of a random Schroedinger operator for an electron
submitted to a magnetic field in a finite but macroscopic two dimensional
system of linear dimensions equal to L. The y direction is periodic and in the
x direction the electron is confined by two smooth increasing boundary
potentials. The eigenvalues of the Hamiltonian are classified according to
their associated quantum mechanical current in the y direction. Here we look at
an interval of energies inside the first Landau band of the random operator for
the infinite plane. In this energy interval, with large probability, there
exist O(L) eigenvalues with positive or negative currents of O(1). Between each
of these there exist O(L^2) eigenvalues with infinitesimal current
O(exp(-cB(log L)^2)). We explain what is the relevance of this analysis to the
integer quantum Hall effect.

</DOC>
<DOC>
<DOCNO> 118037 </DOCNO>
Dependence of Spiral Galaxy Distribution on Viewing Angle in RC3


  The normalized inclination distributions are presented for the spiral
galaxies in RC3. The results show that, except for the bin of
$81^{\circ}$-$90^{\circ}$, in which the apparent minor isophotal diameters that
are used to obtain the inclinations, are affected by the central bulges, the
distributions for Sa, Sab, Scd and Sd are well consistent with the Monte-Carlo
simulation of random inclinations within 3-$\sigma$, and Sb and Sbc almost, but
Sc is different. One reason for the difference between the real distribution
and the Monte-Carlo simulation of Sc may be that some quite inclined spirals,
the arms of which are inherently loosely wound on the galactic plane and should
be classified to Sc galaxies, have been incorrectly classified to the earlier
ones, because the tightness of spiral arms which is one of the criteria of the
Hubble classification in RC3 is different between on the galactic plane and on
the tangent plane of the celestial sphere. Our result also implies that there
might exist biases in the luminosity functions of individual Hubble types if
spiral galaxies are only classified visually.

</DOC>
<DOC>
<DOCNO> 69909 </DOCNO>
Cosmological Parameters 2000


  The cosmological parameters that I emphasize are the age of the universe
$t_0$, the Hubble parameter $H_0 \equiv 100 h$ km s$^{-1}$ Mpc$^{-1}$, the
average matter density $\Omega_m$, the baryonic matter density $\Omega_b$, the
neutrino density $\Omega_\nu$, and the cosmological constant $\Omega_\Lambda$.
The evidence currently favors $t_0 \approx 13$ Gyr, $h \approx 0.65$, $\Omega_m
\approx 0.4\pm0.1$, $\Omega_b = 0.02h^{-2}$, $0.001 < \Omega_\nu < 0.1$, and
$\Omega_\Lambda \approx 0.7$.

</DOC>
<DOC>
<DOCNO> 12303 </DOCNO>
Partial survival and inelastic collapse for a randomly accelerated


  We present an exact derivation of the survival probability of a randomly
accelerated particle subject to partial absorption at the origin. We determine
the persistence exponent and the amplitude associated to the decay of the
survival probability at large times. For the problem of inelastic reflection at
the origin, with coefficient of restitution $r$, we give a new derivation of
the condition for inelastic collapse, $r<r_c=e^{-\pi/\sqrt{3}}$, and determine
the persistence exponent exactly.

</DOC>
<DOC>
<DOCNO> 80859 </DOCNO>
Fermionic Loops in Numerical Stochastic Perturbation Theory


  We discuss the inclusion of fermionic loops contributions in Numerical
Stochastic Perturbation Theory for Lattice Gauge Theories. We show how the
algorithm implementation is in principle straightforward and report on the
status of the project.

</DOC>
<DOC>
<DOCNO> 99516 </DOCNO>
Geometrical Tools for Quantum Euclidean Spaces


  We apply one of the formalisms of noncommutative geometry to $R^N_q$, the
quantum space covariant under the quantum group $SO_q(N)$. Over $R^N_q$ there
are two $SO_q(N)$-covariant differential calculi. For each we find a frame, a
metric and two torsion-free covariant derivatives which are metric compatible
up to a conformal factor and which have a vanishing linear curvature. This
generalizes results found in a previous article for the case of $R^3_q$. As in
the case N=3, one has to slightly enlarge the algebra $R^N_q$; for N odd one
needs only one new generator whereas for N even one needs two. As in the
particular case N=3 there is a conformal ambiguity in the natural metrics on
the differential calculi over $R^N_q$. While in our previous article the frame
was found `by hand', here we disclose the crucial role of the quantum group
covariance and exploit it in the construction. As an intermediate step, we find
a homomorphism from the cross product of $R^N_q$ with $U_qso(N)$ into $R^N_q$,
an interesting result in itself.

</DOC>
<DOC>
<DOCNO> 119150 </DOCNO>
A kinematic and morphological investigation of the asymmetric nebula


  WRA 751 is an evolved massive star in our Galaxy closely resembling Luminous
Blue Variable stars (LBVs). It is surrounded by a nitrogen enriched nebula of
ab out 23" diameter. A comparative study of the nebula's morphology and
kinematics is presented, it supports - together with spectroscopical evidence -
the classification of WRA 751 as a LBV. Images show that the nebula consists of
a nearly spherical shell as well as a bipolar-like structure north and south of
its main body, the Northern and Southern Caps. In contrast to the almost
spherical appearance of the main body of the nebula, the kinematics shows a
deviation even of this part from a classical spherical expansion pattern. From
the present data it can be concluded that the main body expands asymmetrically
(central expansion velocity ~26 km/s), with a thicker shell at the back side. A
bump-like structure can be found to the west of the central star. In addition
to the main body, bipolar kinematic components can be identified with the
morphologically classified Caps. These results put WRA 751 into the class of
LBVs which are surrounded by a nebula with bipolar components, albeit
considerably less pronounced than, for instance, in the classical bipolar LBVs
Eta Car and HR Car.

</DOC>
<DOC>
<DOCNO> 10845 </DOCNO>
Equation of state and Goldstone-mode effects of the three-dimensional


  We investigate numerically the three-dimensional O(2) model on 8^3-160^3
lattices as a function of the magnetic field H. In the low-temperature phase we
verify the H-dependence of the magnetization M induced by Goldstone modes and
determine M in the thermodynamic limit both by extrapolation and by chiral
perturbation theory. This enables us to calculate the corresponding critical
amplitude. At T_c the critical scaling behaviour of the magnetization as a
function of H is used to determine another critical amplitude. In both cases we
find negative corrections-to-scaling. Our low-temperature results are well
described by the perturbative form of the model's magnetic equation of state,
with coefficients determined nonperturbatively from our data. The O(2) scaling
function for the magnetization is found to have a smaller slope than the one
for the O(4) model.

</DOC>
<DOC>
<DOCNO> 70219 </DOCNO>
The 2+1 Dimensional NJL Model at Finite Temperature


  We decribe properties of 2+1-dimensional Nambu-Jona-Lasinio (NJL) models at
finite-temperature, beginning with the model with a discrete chiral symmetry.
We then consider the model with a continuous $U(1) \times U(1)$ chiral
symmetry, describing the restoration of the symmetry at finite temperature. In
each case, we compute the free energy and comment on a recently proposed
constraint based upon it. We conclude with a brief discussion of NJL models
with larger chiral symmetries.

</DOC>
<DOC>
<DOCNO> 101699 </DOCNO>
Gravitational Descendants and the Moduli Space of Higher Spin Curves


  The purpose of this note is introduce a new axiom (called the Descent Axiom)
in the theory of $r$-spin cohomological field theories. This axiom explains the
origin of gravitational descendants in this theory. Furthermore, the Descent
Axiom immediately implies the Vanishing Axiom, explicating the latter (which
has no a priori analog in the theory of Gromov-Witten invariants), in terms of
the multiplicativity of the virtual class. We prove that the Descent Axiom
holds in the convex case, and consequently in genus zero.

</DOC>
<DOC>
<DOCNO> 9619 </DOCNO>
Intrasubband and Intersubband Electron Relaxation in Semiconductor


  We calculate the intersubband and intrasubband many-body inelastic Coulomb
scattering rates due to electron-electron interaction in two-subband
semiconductor quantum wire structures. We analyze our relaxation rates in terms
of contributions from inter- and intrasubband charge-density excitations
separately. We show that the intersubband (intrasubband) charge-density
excitations are primarily responsible for intersubband (intrasubband) inelastic
scattering. We identify the contributions to the inelastic scattering rate
coming from the emission of the single-particle and the collective excitations
individually. We obtain the lifetime of hot electrons injected in each subband
as a function of the total charge density in the wire.

</DOC>
<DOC>
<DOCNO> 84326 </DOCNO>
Monopoles, Dyons and Black Holes in the Four-Dimensional


  A continuum of monopole, dyon and black hole solutions exist in the
Einstein-Yang-Mills theory in asymptotically anti-de Sitter space. Their
structure is studied in detail. The solutions are classified by non-Abelian
electric and magnetic charges and the ADM mass. The stability of the solutions
which have no node in non-Abelian magnetic fields is established. There exist
critical spacetime solutions which terminate at a finite radius, and have
universal behavior. The moduli space of the solutions exhibits a fractal
structure as the cosmological constant approaches zero.

</DOC>
<DOC>
<DOCNO> 179028 </DOCNO>
Density dependence of in-medium nucleon-nucleon cross sections


  The lowest-order correction of the density dependence of in-medium
nucleon-nucleon cross sections is obtained from geometrical considerations of
Pauli-blocking effects. As a by-product, it is shown that the medium
corrections imply an 1/E energy dependence of the density-dependent term.

</DOC>
<DOC>
<DOCNO> 11458 </DOCNO>
Weak-localization type description of conduction in the "anomalous"


  This paper is devoted to the temperature dependence of the resistivity in Si-
MOS samples over the wide range of densities in the ``metallic phase'' (n>n_c)
but not too close to the critical density n_c. Three domains of different
behavior in \rho(T) are identified. These are: [i] quantum domain of
`low-temperatures', where a logarithmic T-dependence of \rho (with
$d\rho/dT<0$) dominates; [ii] semi-classical domain of `high-temperatures', in
which Drude resistivity strongly varies with T (with d\rho/dT>0); and [ii]
crossover between the former two, where a linear T-dependence dominates (with
d\rho/dT>0). In the crossover regime and at higher densities
(n>20x10^{11}/cm^2), \rho(T) goes through a minimum at temperature T_{min}.
Both the absolute value of T_{min} and its dependence on density are found to
be in an agreement with the conventional weak-localization theory. For n
smaller than \sim 20x10^{11}/cm^2, the theoretical estimate for T_{min} falls
outside the experimentally accessible temperature range. This explains the
absence of the minimum at these densities in the data. In total, over the two
decades in the temperature (domains [ii] and [iii]), the two semiclassical
effects mimic the metallic like transport properties. Our analysis shows that
the behaviour of \rho(T) in the region of \rho << h/e^2 can be described
phenomenologically in terms of the conventional weak-localization theory.

</DOC>
<DOC>
<DOCNO> 12677 </DOCNO>
Influence of Capillary Condensation on the Near-Critical Solvation Force


  We argue that in a fluid, or magnet, confined by adsorbing walls which favour
liquid, or (+) phase, the solvation (Casimir) force in the vicinity of the
critical point is strongly influenced by capillary condensation which occurs
below the bulk critical temperature T_c. At T slightly below and above T_c, a
small bulk field h<0, which favours gas, or (-) phase, leads to residual
condensation and a solvation force which is much more attractive (at the same
large wall separation) than that found exactly at the critical point. Our
predictions are supported by results obtained from density-matrix
renormalization-group calculations in a two-dimensional Ising strip subject to
identical surface fields.

</DOC>
<DOC>
<DOCNO> 100113 </DOCNO>
Dual Banach spaces which contain an isometric copy of $L_1$


  A Banach space contains asymptotically isometric copies of $\ell_1$ if and
only if its dual space contains an isometric copy of $L_1$.

</DOC>
<DOC>
<DOCNO> 84619 </DOCNO>
On the extension of the concept of Thin Shells to The Einstein-Cartan


  This paper develops a theory of thin shells within the context of the
Einstein-Cartan theory by extending the known formalism of general relativity.
In order to perform such an extension, we require the general non symmetric
stress-energy tensor to be conserved leading, as Cartan pointed out himself, to
a strong constraint relating curvature and torsion of spacetime. When we
restrict ourselves to the class of space-times satisfying this constraint, we
are able to properly describe thin shells and derive the general expression of
surface stress-energy tensor both in its four-dimensional and in its
three-dimensional intrinsic form. We finally derive a general family of static
solutions of the Einstein-Cartan theory exhibiting a natural family of null
hypersurfaces and use it to apply our formalism to the construction of a null
shell of matter.

</DOC>
<DOC>
<DOCNO> 13602 </DOCNO>
Anomalous dynamic response in the two-dimensional lattice Coulomb gas


  It is demonstrated through Monte Carlo simulations that the one component
lattice Coulomb gas model in two dimensions under certain conditions display
features of an anomalous dynamic response. We suggest that pinning, which can
either be due to the underlying discrete lattice or induced by disorder, is an
essential ingredient behind this anomalous behavior. The results are discussed
in relation to other situations where this response type appears, in particular
the two components neutral Coulomb gas below the Kosterlitz-Thouless
transition, as well as in relation to other findings from theory, simulations,
and experiments on superconductors.

</DOC>
<DOC>
<DOCNO> 83250 </DOCNO>
Security Policy Consistency


  With the advent of wide security platforms able to express simultaneously all
the policies comprising an organization's global security policy, the problem
of inconsistencies within security policies become harder and more relevant.
  We have defined a tool based on the CHR language which is able to detect
several types of inconsistencies within and between security policies and other
specifications, namely workflow specifications.
  Although the problem of security conflicts has been addressed by several
authors, to our knowledge none has addressed the general problem of security
inconsistencies, on its several definitions and target specifications.

</DOC>
<DOC>
<DOCNO> 117065 </DOCNO>
Stable, Strongly Attractive, Two-State Mixture of Lithium Fermions in an


  We use an all-optical trap to confine a strongly attractive two-state mixture
of lithium fermions. By measuring the rate of evaporation from the trap, we
determine the effective elastic scattering cross section (4 PI a^2) to show
that the magnitude of the scattering length |a| is very large, in agreement
with predictions. We show that the mixture is stable against inelastic decay
provided that a small bias magnetic field is applied. For this system, the
s-wave interaction is widely tunable at low magnetic field, and can be turned
on and off rapidly via a Raman PI pulse. Hence, this mixture is well suited for
fundamental studies of an interacting Fermi gas.

</DOC>
<DOC>
<DOCNO> 121672 </DOCNO>
Discovery of a 270 Hz X-Ray Burst Oscillation in the X-Ray Dipper 4U


  We report the discovery of a highly coherent oscillation in a type-I X-ray
burst observed from 4U 1916-053 by the Rossi X-ray Timing Explorer (RXTE). The
oscillation was most strongly detected approx. 1 s after the burst onset at a
frequency of 269.3 Hz, and it increased in frequency over the following 4
seconds of the burst decay to a maximum of around 272 Hz. The total measured
drift of 3.58 +/- 0.41 Hz (1 sigma) represents the largest fractional change in
frequency (1.32 +/- 0.15 %) yet observed in any burst oscillation. If the
asymptotic frequency of the oscillation is interpreted in terms of a decoupled
surface burning layer, the implied neutron star spin period is around 3.7 ms.
However, the expansion of the burning layer required to explain frequency drift
during the burst is around 80 m, substantially larger than expected
theoretically (assuming rigid rotation). The oscillation was not present in the
persistent emission before the burst, nor in the initial rise. When detected
its amplitude was 6-12% (RMS) with a roughly sinusoidal profile. The burst
containing the oscillation showed no evidence for photospheric radius
expansion, while at least 5 of the other 9 bursts observed from the source by
RXTE during 1996 and 1998 did. No comparable oscillations were detected in the
other bursts. A pair of kilohertz quasi-periodic oscillations (QPOs) has been
previously reported from this source with a mean separation of 348 +/- 12 Hz.
4U 1916-053 is the first example of a source where the burst oscillation
frequency is significantly smaller than the frequency separation of the kHz
QPOs.

</DOC>
<DOC>
<DOCNO> 70911 </DOCNO>
Cooper-Mesons in the Color-Flavor-Locked Superconducting Phase of Dense


  QCD superconductors in the color-flavor-locked (CFL) phase sustain
excitations (``Cooper'' mesons) that can be described as pairs of particles or
holes around a gapped Fermi surface. In weak coupling and to leading logarithm
accuracy the masses, decay constants and form factors of the scalar,
pseudoscalar, vector and axial-vector excitations, which explicitly are of
finite size, can be calculated exactly. Furthermore, the constraints of this
microscopic calculation on the effective-lagrangian description and the
computation of the generalized triangle anomaly are discussed.

</DOC>
<DOC>
<DOCNO> 118748 </DOCNO>
A search for Jovian-mass planets around CM Draconis using eclipse minima


  For the eclipsing binary system CM Draconis, eclipse minimum times have been
monitored with high precision between 1994 and 1999. Periodic deviations of
minimum times from a linear ephemeris may indicate the presence of an orbiting
third body. Individual measurements of 41 eclipse minimum times result in a
standard deviation from linear ephemeris of 5.74 seconds. A power spectral
analysis of the residuals reveals only one periodicity with more then 2 seconds
amplitude. This feature, with a periodicity between 750 and 1050 days has an
amplitude of 2.8+-0.5 seconds, and is also present with similar phases if the
power spectral analysis is performed independently for primary and secondary
eclipses. It would be compatible with a planet of 1.5-3 Jupiter masses at an
orbital distance of 1.1-1.45 AU to the binary barycenter. The assignation of a
planet to the CM Dra system can however only be upheld if this periodicity can
be followed in future observations for several years. For low-mass eclipsing
binary stars, the method of eclipse minimum timing allows one to reach mass
limits for the detection of third bodies well below that feasible by radial
velocity measurements.

</DOC>
<DOC>
<DOCNO> 7860 </DOCNO>
The Baxter Revolution


  I review the revolutionary impact Rodney Baxter has had on statistical
mechanics beginning with his solution of the 8 vertex model in 1971 and the
invention of corner transfer matrices in 1976 to the creation of the RSOS
models in 1984 and his continuing current work on the chiral Potts model.

</DOC>
<DOC>
<DOCNO> 99845 </DOCNO>
Proper forcing and $L({\mathbb R})$


  We present two ways in which the model $L({\mathbb R})$ is canonical assuming
the existence of large cardinals. We show that the theory of this model, with
{\em ordinal} parameters, cannot be changed by small forcing; we show further
that a set of ordinals in $V$ cannot be added to $L({\mathbb R})$ by small
forcing. The large cardinal needed corresponds to the consistency strength of
$AD^{L({\mathbb R})}$; roughly $\omega$ Woodin cardinals.

</DOC>
<DOC>
<DOCNO> 169668 </DOCNO>
Time of arrival in the presence of interactions


  We introduce a formalism for the calculation of the time of arrival t at a
space point for particles traveling through interacting media. We develop a
general formulation that employs quantum canonical transformations from the
free to the interacting cases to construct t in the context of the Positive
Operator Valued Measures. We then compute the probability distribution in the
times of arrival at a point for particles that have undergone reflection,
transmission or tunneling off finite potential barriers. For narrow Gaussian
initial wave packets we obtain multimodal time distributions of the reflected
packets and a combination of the Hartman effect with unexpected retardation in
tunneling. We also employ explicitly our formalism to deal with arrivals in the
interaction region for the step and linear potentials.

</DOC>
<DOC>
<DOCNO> 11606 </DOCNO>
On the structure and stability of germanium nanoparticles


  In order to control and tailor the properties of nanodots, it is essential to
separate the effects of quantum confinement from those due to the surface, and
to gain insight into the influence of preparation conditions on the dot
physical properties. We address these issues for the case of small Ge clusters
(1-3 nm), using a combination of empirical and first-principles molecular
dynamics techniques. Our results show that over a wide temperature range the
diamond structure is more stable than tetragonal, ST12-like structures for
clusters containing more than 50 atoms; however, the magnitude of the energy
difference between the two geometries is strongly dependent on the surface
properties. Based on our structural data, we propose a mechanism which may be
responsible for the formation of metastable ST12 clusters in vapor deposition
experiments, by cold quenching of amorphous nanoparticles with unsaturated,
reconstructed surfaces.

</DOC>
<DOC>
<DOCNO> 152253 </DOCNO>
The Enhancon, Multimonopoles and Fuzzy Geometry


  The presentation at Strings 2000 was intended to be in two main parts, but
there was only time for part one. However both parts appeared on the online
proceedings, and are also included in this document. The first part concerns an
exploration of the connection between the physics of the `enhancon' geometry
arising from wrapping N D6-branes on the K3 manifold in Type IIA string theory
and that of a charge N BPS multi-monopole. This also relates to the physics of
2+1 dimensional SU(N) gauge theory with eight supercharges. The main results
uncovered by this exploration are: a) better insight into the non-perturbative
geometry of the enhancon; b) the structure of the moduli space geometry, and
its characterisation in terms of generalisations of an Atiyah-Hitchin-like
manifold; c) the use of Nahm data to describe aspects of the geometry, showing
that the enhancon locus itself has a description as a fuzzy sphere. Part two
discusses the addition of extra D2-branes into the geometry. Two probe
computations show the difference between the geometry as seen by D2-branes and
that seen by wrapped D6-branes, and the accompanying gauge theory
interpretations are discussed.

</DOC>
<DOC>
<DOCNO> 151436 </DOCNO>
Calibration of Local Chiralities and Time-Arrows Based on Quantum


  Unlike classical physics, quantum mechnanics is sensitive to mistaken choice
of chiralities or time-arrows of local reference systems. Quantum correlations
between distant electron spins, for instance, would reveal a mistaken local
chirality. Local polarization measurements and classical communication enable
the distant partners to compare their local chiralities. Local time-arrows can
be calibrated in a similar way.

</DOC>
<DOC>
<DOCNO> 102418 </DOCNO>
Floer homology and its continuity for non-compact Lagrangian


  We give a construction of the Floer homology of the pair of {\it non-compact}
Lagrangian submanifolds, which satisfies natural continuity property under the
Hamiltonian isotopy which moves the infinity but leaves the intersection set of
the pair compact. This construction uses the concept of Lagrangian cobordism
and certain singular Lagrangian submanifolds. We apply this construction to
conormal bundles (or varieties) in the cotangent bundle, and relate it to a
conjecture made by MacPherson on the intersection theory of the characteristic
Lagrangian cycles associated to the perverse sheaves constructible to a complex
stratification on the complex algebraic manifold.

</DOC>
<DOC>
<DOCNO> 69659 </DOCNO>
Higher-twist contributions to F_L and F_2 from instantons


  We study the twist-4 contribution to the unpolarized nucleon structure
functions, F_L and F_2, in an approach where the vacuum structure of QCD is
described by a dilute medium of instantons ($\bar\rho / \bar R \ll 1$). The
dominant power corrections come from the twist-4 quark-gluon operators and are
of the order $1/(\bar\rho^2 Q^2)$. The contributions from four-quark operators
are suppressed. The approach predicts large 1/Q^2-corrections to F_L, in
agreement with the results of QCD fits to the data.

</DOC>
<DOC>
<DOCNO> 121136 </DOCNO>
What Is The BBN Prediction for the Baryon Density and How Reliable Is


  Together, the standard theory of big-bang nucleosynthesis (BBN) and the
primeval deuterium abundance now very precisely peg the baryon density. Based
upon our analysis of the deuterium data and the theoretical uncertainties
associated with the BBN predictions, we determine Omega_B h^2 = 0.020\pm 0.002
(95% C.L.), with the uncertainty from the measured deuterium abundance about
twice that from the predicted abundance. We discuss critically the reliability
of the BBN baryon density, and in light of possible systematic uncertainties
also derive a very conservative range. We conclude that within the standard
cosmology and standard theory of BBN a baryon density Omega_B h^2=0.032 (the
central value implied by recent CMB anisotropy measurements) simply cannot be
accommodated.

</DOC>
<DOC>
<DOCNO> 69077 </DOCNO>
Quintessence and CMB


  A particular kind of quintessence is considered, with equation of motion
$p_Q/\rho_Q = -1$, corresponding to a cosmological term with time-dependence
$\Lambda(t) = \Lambda(t_0) (R(t_0)/R(t))^{P}$ which we examine initially for $0
\leq P < 3$. Energy conservation is imposed, as is consistency with big-bang
nucleosynthesis, and the range of allowed $P$ is thereby much restricted to $0
\leq P < 0.2$. The position of the first Doppler peak is computed analytically
and the result combined with analysis of high-Z supernovae to find how values
of $\Omega_m$ and $\Omega_{\Lambda}$ depend on $P$.

</DOC>
<DOC>
<DOCNO> 151303 </DOCNO>
Gravitational Couplings for Gop-Planes and y-Op-Planes


  The Wess-Zumino actions for generalized orientifold planes (GOp-planes) and
y-deformed orientifold planes (yOp-planes) are presented and two series power
expantions are realized from whiches processes that involves
GOp-planes,yOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally
non-standard GOp-planes and y-Op-planes are showed.

</DOC>
<DOC>
<DOCNO> 116375 </DOCNO>
Ultra-refraction phenomena in Bragg mirrors


  We show numerically for the first time that ultra-refractive phenomena do
exist in one-dimensional photonic crystals: we exhibit the main features of
ultra-refraction, that is the enlargement and the splitting of an incident
beam. We give a very simple explanation of these phenomena in terms of the
photonic band structure of these media.

</DOC>
<DOC>
<DOCNO> 150815 </DOCNO>
Consistent interactions in the Hamiltonian BRST formalism


  A Hamiltonian BRST deformation procedure for obtaining consistent
interactions among fields with gauge freedom is proposed. The general theory is
exemplified on the three-dimensional Chern-Simons model.

</DOC>
<DOC>
<DOCNO> 71526 </DOCNO>
Phenomenology of single transverse spin asymmetries


  A unified and consistent phenomenological approach to single transverse spin
asymmetries in the framework of perturbative QCD, with the inclusion of a new
class of spin and k_T dependent distribution and fragmentation functions, is
presented. As an example, results on A_N(p(pol) p --> pion X) and P_Lambda(p p
-->Lambda(pol) X) are shown.

</DOC>
<DOC>
<DOCNO> 152117 </DOCNO>
Introducing Quarks in Confining Strings via the Fermionic Wilson Loop


  In the world line representation of the fermionic effective action for QCD
the interaction between Fermions and the gauge field is contained in the
fermionic Wilson loop, namely the Wilson loop for a spin-half particle. It is
argued that a string representation of the fermionic Wilson loop can provide a
link connecting QCD with a dual description of a meson as a quark and an
antiquark connected by a string. This is illustrated by obtaining such a
representation in compact U(1) gauge theories. The resulting description
contains information about the interaction of the spin of the quark with the
world sheet degrees of freedom. Such interactions may be of importance in the
realization of chiral symmetry in the string picture of QCD, and for
delineating the possible presence of a world sheet supersymmetry in QCD
strings.

</DOC>
<DOC>
<DOCNO> 122641 </DOCNO>
Star Formation History in the Solar Vicinity


  The star formation history in the solar neighbourhood is inferred comparing a
sample of field stars from the Hipparcos Catalog with synthetic CMDs. We
considered separately the main sequence and the red giant region of the HR
diagram. The criteria for our best solutions are based on the $\chi^{2}$
minimization of star distributions in selected zones of the HR diagram. Our
analysis suggests that: a) the solutions are compatible with a Salpeter IMF and
with {\sl a star formation rate increasing, in a broad sense, from the
beginning to the present time}; b) the deduced volume mass densities and the
corresponding absolute scale of the SFR solutions are strongly influenced by
the initial mass function slope of low mass stars (below 0.5 Mo); c) the
stellar evolutionary models are not completely adequate: in fact {\sl the
theoretical ratio between the He-burning and MS star numbers is always a factor
1.5 greater than the observational value}. This fact could indicate the need of
a more efficient overshoot in the evolutionary models, or a different mixing
theory.

</DOC>
<DOC>
<DOCNO> 102793 </DOCNO>
Invitation to higher local fields, Part II, section 9: Local reciprocity


  This is an introduction to noncommutative local reciprocity maps for totally
ramified Galois extensions with arithmetically profinite group. These maps in
general are not homomorphisms but Galois cycles; a description of their image
and kernel is included.

</DOC>
<DOC>
<DOCNO> 70507 </DOCNO>
The Neutron EDM in the SM : A Review


  We review the status of the electric dipole moment (EDM) of neutron in the
Standard Model (SM). The contributions of the strong and electroweak
interactions are discussed seperately. In each case the structure of the
Lagrangian and the sources of CP violation are specified, and calculational
details are given subsequently. These two contributions to the neutron EDM
exist in any extension of the SM including supersymmetry, two--doublet models
as well as models with more than three generations of fermions. We do not
discuss the EDM in such extensions; however, we briefly summarize their
predictions with a detailed account of the related literature.

</DOC>
<DOC>
<DOCNO> 84234 </DOCNO>
Principia Physica


  A comprehensive physical theory explains all aspects of the physical
universe, including quantum aspects, classical aspects, relativistic aspects,
their relationships, and unification. The central nonlocality principle leads
to a nonlocal geometry that explains entire quantum phenomenology, including
two-slit experiment, Aspect-type experiments, quantum randomness, tunneling,
etc. The infinitesimal aspect of this geometry is a usual (differential)
geometry, various aspects of which are energy-momentum, spin-helicity,
electric, color and flavor charges. Their interactions are governed by a
mathematically automatic field equation - also a grand conservation principle.
New predictions: a new particle property; bending-of-light estimates refined
over relativity's; shape of the universe; a no-gravitational-singularity
theorem, etc. Nonlocal physics is formulated using a nonlocal calculus and
nonlocal differential equations, replacing inadequate local concepts of
Newton's calculus and partial differential equations. Usual quantum formalisms
follow from our theory - the latter doesn't rest on the former.

</DOC>
<DOC>
<DOCNO> 100023 </DOCNO>
Universal Similarity Factorization Equalities over Complex Clifford


  A set of valuable universal similarity factorization equalities are
established over complex Clifford algebras $\Cn.$ Through them matrix
representations of complex Clifford algebras $\Cn$ can directly be derived, and
their properties can easily be determined.

</DOC>
<DOC>
<DOCNO> 101118 </DOCNO>
Integrable Schr\"odinger operators with magnetic fields: factorisation


  The factorisation method for Schr\"odinger operators with magnetic fields on
a two-dimensional surface $M^2$ with non-trivial metric is investigated. This
leads to the new integrable examples of such operators and brings a new look at
some classical problems such as Dirac magnetic monopole and Landau problem. The
global geometric aspects and related spectral properties of the operators from
the factorisation chains are discussed in details. We also consider the Laplace
transformations on a curved surface and extend the class of Schr\"odinger
operators with two integrable levels introduced in the flat case by S.P.Novikov
and one of the authors.

</DOC>
<DOC>
<DOCNO> 10596 </DOCNO>
Dislocation theory as a 3-dimensional translation gauge theory


  We consider the static elastoplastic theory of dislocations in an
elastoplastic material. We use a Yang-Mills type Lagrangian (the teleparallel
equivalent of Hilbert-Einstein Lagrangian) and some Lagrangians with
anisotropic constitutive laws. The translational part of the generalized affine
connection is utilized to describe the theory of elastoplasticity in the
framework of a translation gauge theory. We obtain a system of Yang-Mills field
equations which express the balance of force and moment.

</DOC>
<DOC>
<DOCNO> 85389 </DOCNO>
Energy Release on the Surface of a Rapidly Rotating Neutron Star during


  The total energy E of a star as a function of its angular momentum J and mass
M in the Newtonian theory: E = E(J, M) [in general relativity, the
gravitational mass M of a star as a function of its angular momentum J and rest
mass m, M = M(J, m)], is used to determine the remaining parameters (angular
velocity, equatorial radius, chemical potential, etc.) in the case of rigid
rotation. Expressions are derived for the energy release during accretion onto
a cool (with constant entropy), rapidly rotating neutron star (NS) in the
Newtonian theory and in general relativity. A separate analysis is performed
for the cases where the NS equatorial radius is larger and smaller than the
radius of the marginally stable orbit in the disk plane. An approximate formula
is proposed for the NS equatorial radius for an arbitrary equation of state,
which matches the exact one at J = 0.

</DOC>
<DOC>
<DOCNO> 10643 </DOCNO>
Vibration-induced "thermally activated" jamming transition in granular


  The quasi-static frequency response of a granular medium is measured by a
forced torsion oscillator method, with forcing frequency $f_{p}$ in the range
$10^{-4}$ Hz to 5 Hz, while weak vibrations at high-frequency $f_{s}$, in the
range 50 Hz to 200 Hz, are generated by an external shaker. The intensity of
vibration, $\Gamma $, is below the fluidization limit. A loss factor peak is
observed in the oscillator response as a function of $\Gamma $ or $f_{p}$. In a
plot of $\ln f_{p}$ against $1/\Gamma $, the position of the peak follows an
Arrhenius-like behaviour over four orders of magnitude in $f_{p}$. The data can
be described as a stochastic hopping process involving a probability factor
$\exp(-\Gamma_{j}/\Gamma)$ with $\Gamma_{j}$ a $f_{s}$-dependent characteristic
vibration intensity. A $f_{s}$-independent description is given by
$\exp(-\tau_{j}/\tau)$, with $\tau_{j}$ an intrinsic characteristic time, and
$\tau =\Gamma ^{n}/2\pi f_{s}$, n=0.5-0.6, an empirical control parameter with
unit of time. $\tau$ is seen as the effective average time during which the
perturbed grains can undergo structural rearrangement. The loss factor peak
appears as a crossover in the dynamic behaviour of the vibrated granular
system, which, at the time-scale $ 1/f_{p}$, is solid-like at low $\Gamma$, and
the oscillator is jammed into the granular material, and is fluid-like at high
$\Gamma$, where the oscillator can slide viscously.

</DOC>
<DOC>
<DOCNO> 116750 </DOCNO>
Topological Constraints on Long-Distance Neutrino Mixtures


  A new internal description of fundamental fermions (quarks and leptons),
based on a matrix-generalization (F) of the scalar fermion-number f, predicts
that only three families of quarks and leptons, and their associated neutrinos
(nu_e, nu_mu and nu_tau), exist. Moreover, this description places important
topological constraints on neutrino mixing. For example, with respect to F, the
topology of the nu_e (nu_mu or nu_tau) is that of a cylinder (Mobius strip).
Assuming that a change in topology dudring neutrino-neutrino transitions is
suppressed (e.g., one cannot continuously deform a donut into a sphere), while
neutrino-neutrino transitions without topology-change are (relatively)
enhanced, one may have an explanation for recent short-distance experimental
observations of (nearly) maximal nu_mu-nu_tau mixing at the Super Kamiokande.
To test this idea, I was able to use simple topological arguments to deduce a
matrix describing long-distance neutrino mixtures, which is identical to that
proposed by Georgi and Glashow on different grounds. Experimental confirmation
of this prediction would strongly support the new description of fundamental
fermions, which requires, among other things, that the nu_e and (nu_mu or
nu_tau) neutrinos start life as topoligically-distinct quantum objects.

</DOC>
<DOC>
<DOCNO> 101479 </DOCNO>
Moduli spaces of framed sheaves on certain ruled surfaces over elliptic


  Fix a ruled surface S obtained as the projective completion of a line bundle
L on a complex elliptic curve; we study the moduli problem of parametrizing
certain pairs consisting of a sheaf E on S and a map of E to a fixed reference
sheaf on S. We prove that the full moduli stack for this problem is
representable by a scheme in some cases. Moreover, the moduli stack admits an
action by the group ${\mathbf C}^*$, and we determine its fixed-point set,
which leads in some special cases to explicit formulas for the rational
homology of the moduli space.

</DOC>
<DOC>
<DOCNO> 39670 </DOCNO>
Featuring the structure functions geometry


  We consider geometrical properties of the polarized and unpolarized structure
functions and provide definition for the $b$--dependent structure functions. It
is shown that unitarity does not allow factorized form of the structure
functions over the $x$ and $b$ variables. We conclude that the spin of
constituent quark has a significant orbital angular momentum component.

</DOC>
<DOC>
<DOCNO> 70174 </DOCNO>
Comment on "A Convergent Series for the QED Effective Action" by Y. M.


  Complete results were obtained by us in [Can. J. Phys. 71, 389 (1993)] for
convergent series representations of both the real and the imaginary part of
the QED effective action; these derivations were based on correct intermediate
steps. In this comment, we argue that the physical significance of the
"logarithmic correction term" found by Cho and Pak in [Phys. Rev. Lett. 86,
1947 (2001)] in comparison to the usual expression for the QED effective action
remains to be demonstrated.

</DOC>
<DOC>
<DOCNO> 117302 </DOCNO>
Fourth Order Gradient Symplectic Integrator Methods for Solving the


  We show that the method of splitting the operator ${\rm e}^{\epsilon(T+V)}$
to fourth order with purely positive coefficients produces excellent algorithms
for solving the time-dependent Schr\"odinger equation. These algorithms require
knowing the potential and the gradient of the potential. One 4th order
algorithm only requires four Fast Fourier Transformations per iteration. In a
one dimensional scattering problem, the 4th order error coefficients of these
new algorithms are roughly 500 times smaller than fourth order algorithms with
negative coefficient, such as those based on the traditional Ruth-Forest
symplectic integrator. These algorithms can produce converged results of
conventional second or fourth order algorithms using time steps 5 to 10 times
as large. Iterating these positive coefficient algorithms to 6th order also
produced better converged algorithms than iterating the Ruth-Forest algorithm
to 6th order or using Yoshida's 6th order algorithm A directly.

</DOC>
<DOC>
<DOCNO> 69363 </DOCNO>
Electroweak Physics in Six-Fermion Processes at Future Colliders


  Recent developments in the field of complete electroweak tree-level
calculations for six-fermion final states in e+ e- collisions are briefly
reviewed. Particular attention is given to top-quark and Higgs boson physics,
which are items of primary importance at the Next Linear Collider. The
relevance of electroweak backgrounds and finite-width effects is discussed,
showing the importance of complete calculations for precision studies at the
colliders operating in the TeV energy range.

</DOC>
<DOC>
<DOCNO> 84985 </DOCNO>
Self interacting Brans Dicke cosmology and Quintessence


  Recent cosmological observations reveal that we are living in a flat
accelerated expanding universe. In this work we have investigated the nature of
the potential compatible with the power law expansion of the universe in a self
interacting Brans Dicke cosmology with a perfect fluid background and have
analyzed whether this potential supports the accelerated expansion. It is found
that positive power law potential is relevant in this scenario and can drive
accelerated expansion for negative Brans Dicke coupling parameter $\omega$. The
evolution of the density perturbation is also analyzed in this scenerio and is
seen that the model allows growing modes for negative $\omega$.

</DOC>
<DOC>
<DOCNO> 122510 </DOCNO>
Stellar Coronae with \textit{XMM-Newton} RGS. II. X-ray Variability


  First results from high-resolution coronal spectroscopy of flares with the
Reflection Grating Spectrometers on board the \textit{XMM-Newton} satellite are
reviewed. Rotational modulation in the X-ray light curve of HR 1099 is
discussed. Results from time-dependent spectroscopy of flares in the active
stars HR 1099, AB Dor, YY Gem are also presented. Variations in the shape of
the emission measure distributions, in the abundances and in the average
density of the cool plasma are discussed.

</DOC>
<DOC>
<DOCNO> 11315 </DOCNO>
Nonequilibrium theory of scanning tunneling spectroscopy via adsorbate


  We report on a fully nonequilibrium theory of the scanning tunneling
microscopy (STM) through resonances induced by impurity atoms adsorbed on metal
surfaces. The theory takes into account the effect of the tunneling current and
finite bias on the system and is valid for arbitrary intra-adsorbate electron
correlation strength. It is thus applicable to the recent STM experiments on
Kondo impurities.

</DOC>
<DOC>
<DOCNO> 40657 </DOCNO>
Pion Polarizabilities and Hybrid Meson Structure at CERN COMPASS


  CERN COMPASS can investigate pion-photon interactions, to achieve a unique
Primakoff Coulomb physics program, centered on pion polarizability and hybrid
meson structure studies. COMPASS uses 100-280 GeV beams (muon, pion) and a
virtual photon target, and magnetic spectrometers and calorimeters to measure
the complete kinematics of pion-photon reactions. The COMPASS experiment is
scheduled to begin data runs in 2001. Pion polarizabilities and hybrid mesons
can be studied via the Primakoff reactions pion + gamma ---> pion + gamma and
pion + gamma ---> Hybrid. The electric (alpha) and magnetic (beta) pion and
Kaon polarizabilities characterize their deformation in an electromagnetic
field, as occurs during gamma-pion Compton scattering. They depend on the
rigidity of their internal structures as composite particles, and are therefore
important quantities to test the validity of theoretical models. The
polarizability measurement will provide an important new test of QCD chiral
dynamics. The studies of quark-antiquark-gluon hybrid mesons would improve our
understanding of these exotic mesons. COMPASS may improve previous Primakoff
polarizability and Hybrid studies by two to three orders of magnitude.
  Appendixes A (Pion and Kaon Polarizabilities at COMPASS) and B (Hybrid Meson
Structure at COMPASS) of this contribution include evaluations submitted to the
APS DNP Town Meeting White Paper Committee. These summarize (1) the fundamental
scientific issues addressed, (2) major achievements since the last DNP long
range plan, (3) the short and long term U.S. outlook, (4) comparison of U.S.
and global effort, (5) other issues.

</DOC>
<DOC>
<DOCNO> 7834 </DOCNO>
Stripe ordering and two-gap model for underdoped cuprates


  The evidence of edge-gaps around the M-points in the metallic state of
underdoped cuprates has triggered a very active debate on their origin. We
first consider the possibility that this spectroscopic feature results from a
quasi-static charge ordering taking place in the underdoped regime. It comes
out that to explain the coexistence of gaps and arcs on the Fermi surface the
charge modulation should be in an eggbox form. In the lack of evidences for
that, we then investigate the local pairing induced by charge-stripe
fluctuations. A proper description of the strong anisotropy of both the
interactions and the Fermi velocities requires a two-gap model for pairing. We
find that a gap due to incoherent pairing forms near the M-points, while
coherence is established by the stiffness of the pairing near the nodal points.
The model allows for a continuos evolution from a pure BCS pairing (over- and
optimally doped regime) to a mixed boson-fermion model (heavily underdoped
regime).

</DOC>
<DOC>
<DOCNO> 40254 </DOCNO>
Roles of Chiral Symmetry and the Sigma Meson in Hadron and Nuclear


  We first review the recent accumulating evidences of the existence of a
scalar-isoscalar meson with the mass 500 to 800 MeV which may be identified
with the sigma meson as the quantum fluctuation of the amplitude of the chiral
order parameter. We indicate that phase shift analyses which respect chiral
symmetry (ChS), analyticity and crossing symmetry of the scattering amplitude
show the sigma meson pole in the $s$-channel as well as the $\rho$ meson pole
in the $t$-channel in the pi-pi scattering in the $I=J=0$ channel. We emphasize
that the existence of the $\sigma$ resonance does not contradict with the
success of the chiral perturbation theory; phenomenological difficulties with
the renormalizable linear sigma model do not necessarily deny the validity of
the linear representation of ChS of QCD as given by the NJL-like models which
not only admit the $\sigma$ resonance but also reproduce the coupling constants
$L_i$ and $H_i$ appearing the nonlinear chiral lagrangian. We give some
examples of the hadronic phenomena which are naturally accounted for with the
$\sigma$ meson. We show that the the $\sigma$ meson as the amplitude
fluctuation of the chiral order parameter may be more clearly identified than
in free space in hot and/or dense matter, even in finite nuclei where partial
restoration of ChS may be realized.

</DOC>
<DOC>
<DOCNO> 11921 </DOCNO>
Coupled Ising models with disorder


  In this paper we study the phase diagram of two Ising planes coupled by a
standard spin-spin interaction with bond randomness in each plane. The whole
phase diagram is analyzed by help of Monte Carlo simulations and field theory
arguments.

</DOC>
<DOC>
<DOCNO> 71713 </DOCNO>
Theoretical Chiral Dynamics


  The reasons why a considerable effort is made to resolve the low energy
structure of QCD are discussed. The effective field theory used for this
purpose is illustrated with the recent progress made in the predictions for
pipi scattering and in understanding the low energy properties of the theory in
the large Nc limit.

</DOC>
<DOC>
<DOCNO> 99946 </DOCNO>
A Crossed Module giving the Godbillon-Vey Cocycle


  We find crossed modules, i.e. certain 4 term exact sequences, associated to
the Godbillon-Vey class for W_1, Vect(S^1), Vect_{1,0}(\Sigma) and
Hol(\Sigma_r), i.e. for the Lie algebras of formal vector fields in 1 variable,
vector fields on the circle, differentiable vector fields of holomorphic type
on a Riemann surface and holomorphic vector fields on an open Riemann surface.

</DOC>
<DOC>
<DOCNO> 84561 </DOCNO>
Noether Currents of Charged Spherical Black Holes


  We calculate the Noether currents and charges for Einstein-Maxwell theory
using a version of the Wald approach. In spherical symmetry, the choice of time
can be taken as the Kodama vector. For the static case, the resulting combined
Einstein-Maxwell charge is just the mass of the black hole. Using either a
classically defined entropy or the Iyer-Wald selection rules, the entropy is
found to be just a quarter of the area of the trapping horizon. We propose
identifying the combined Noether charge as an energy associated with the Kodama
time. For the extremal black hole case, we discuss the problem of Wald's
rescaling of the surface gravity to define the entropy.

</DOC>
<DOC>
<DOCNO> 100711 </DOCNO>
Some Ricci Flat (pseudo-) Riemannian Geometries


  We define a class of two dimensional surfaces conformally related to minimal
surfaces in flat three dimensional geometries. By the utility of the metrics of
such surfaces we give a construction of the metrics of $2 N$ dimensional Ricci
flat (pseudo-) Riemannian geometries.

</DOC>
<DOC>
<DOCNO> 11466 </DOCNO>
Cluster update and recognition


  We present a fast and robust cluster update algorithm that is especially
efficient in implementing the task of image segmentation using the method of
superparamagnetic clustering. We apply it to a Potts model with spin
interactions that are are defined by gray-scale differences within the image.
Motivated by biological systems, we introduce the concept of neural inhibition
to the Potts model realization of the segmentation problem. Including the
inhibition term in the Hamiltonian results in enhanced contrast and thereby
significantly improves segmentation quality. As a second benefit we can - after
equilibration - directly identify the image segments as the clusters formed by
the clustering algorithm. To construct a new spin configuration the algorithm
performs the standard steps of (1) forming clusters and of (2) updating the
spins in a cluster simultaneously. As opposed to standard algorithms, however,
we share the interaction energy between the two steps. Thus the update
probabilities are not independent of the interaction energies. As a
consequence, we observe an acceleration of the relaxation by a factor of 10
compared to the Swendson and Wang procedure.

</DOC>
<DOC>
<DOCNO> 169932 </DOCNO>
An intuitive Hamiltonian for quantum search


  We present new intuition behind Grover's quantum search algorithm by means of
a Hamiltonian. Given a black-box Boolean function f mapping strings of length n
into {0,1} such that f(w) = 1 for exactly one string w, L. K. Grover describes
a quantum algorithm that finds w in O(2^{n/2}) time. Farhi & Gutmann show that
w can also be found in the same amount time by letting the quantum system
evolve according to a simple Hamiltonian depending only on f. Their system
evolves along a path far from that taken by Grover's original algorithm,
however. The current paper presents an equally simple Hamiltonian matching
Grover's algorithm step for step. The new Hamiltonian is similar in appearance
from that of Farhi & Gutmann, but has some important differences, and provides
new intuition for Grover's algorithm itself. This intuition both contrasts with
and supplements other explanations of Grover's algorithm as a rotation in two
dimensions, and suggests that the Hamiltonian-based approach to quantum
algorithms can provide a useful heuristic for discovering new quantum
algorithms.

</DOC>
<DOC>
<DOCNO> 67879 </DOCNO>
B to D(*) pi- beyond naive factorization in the heavy quark limit


  Nonleptonic decays B to D pi- or B to D* pi- are dominated by factorizable
contributions. In the heavy quark limit, nonfactorizable contribution arises
from strong radiative correction and power corrections in 1/m_b. I calculate
the decay rates for B to D(*) pi- at next-to-leading order in strong
interaction, including nonfactorizable corrections. The result is expressed in
terms of a convolution of the hard scattering amplitude and the pion wave
function. The decay amplitudes in this method are independent of the gauge, the
renormalization scale, and the renormalization scheme. The effects of the
nonfactorizable contribution are discussed and numerical estimates are
presented.

</DOC>
<DOC>
<DOCNO> 122150 </DOCNO>
Supernova Studies at ORLaND


  A new facility to measure neutrino mass differences and mixing angles and
neutrino-nucleus cross sections, such as the proposed ORLaND facility at Oak
Ridge, would contribute to the experimental determination of vacuum mixing
parameters and would provide an experimental foundation for the many
neutrino-nucleus weak interaction rates needed in supernova models. This would
enable more realistic supernova models and a far greater ability to cull
fundamental physics from these models by comparing them with detailed
observations. Charged- and neutral-current neutrino interactions on nuclei in
the stellar core play a central role in supernova dynamics, nucleosynthesis,
and neutrino detection. Measurements of these reactions on select, judiciously
chosen targets would provide an invaluable test of the complex theoretical
models used to compute the neutrino-nucleus cross sections.

</DOC>
<DOC>
<DOCNO> 67739 </DOCNO>
Neutrino Masses and Mixing one Decade from Now


  We review the status of neutrino masses and mixings in the light of the solar
and atmospheric neutrino data. The result from the LSND experiment is also
considered. We discuss the present knowledge and the expected sensitivity to
the neutrino mixing parameters in the simplest schemes proposed to reconcile
these data some of which include a light sterile neutrino in addition to the
three standard ones.

</DOC>
<DOC>
<DOCNO> 69590 </DOCNO>
Relativistic quark-antiquark potential and heavy quarkonium mass spectra


  A general approach to accounting for retardation effects in the long-range
(confining) part of the quark-antiquark potential is presented. The charmonium
and bottomonium mass spectra are calculated with the systematic account of
relativistic and retardation effects and the one-loop radiative corrections. A
good fit to available experimental data on the mass spectra is obtained.

</DOC>
<DOC>
<DOCNO> 121148 </DOCNO>
Hierarchical clustering and formation of power-law correlation in


  The process of formation of fractal structure in one-dimensional
self-gravitating system is examined numerically. It is clarified that
structures created in small spatial scale grow up to larger scale through
clustering of clusters, and form power-law correlation.

</DOC>
<DOC>
<DOCNO> 178465 </DOCNO>
A hybrid version of the tilted axis cranking model and its application


  A hybrid version the deformed nuclear potential is suggested, which combines
a spherical Woods Saxon potential with a deformed Nilsson potential. It removes
the problems of the conventional Nilsson potential in the mass 130 region.
Based on the hybrid potential, tilted axis cranking calculations are carried
out for the magnetic dipole band in ^{128}Ba.

</DOC>
<DOC>
<DOCNO> 9438 </DOCNO>
Phase-Sensitive Tetracrystal Pairing-Symmetry Measurements and Broken


  A detailed analysis of the symmetric tetracrystal geometry used in
phase-sensitive pairing symmetry experiments on high Tc superconductors is
carried out for both bulk and surface time-reversal symmetry-breaking states,
such as the d+id' and d+is states. The results depend critically on the
substrate geometry. In the general case, for the bulk d+id' (or d+is) state,
the measured flux quantization should in general not be too different from that
obtained in the pure d-wave case, provided |d'| << |d| (or |s| << |d|).
However, in one particular high symmetry geometry, the d+id' state gives
results that allow it to be distinguished from the pure d and the d + is
states. Results are also given for the cases where surface d+is or d+id' states
occur at a [110] surface of a bulk d-wave superconductor. Remarkably, in the
highest symmetry geometry, a number of the broken time-reversal symmetry states
discussed above give flux quantization conditions usually associated with
states not having broken time- reversal symmetry.

</DOC>
<DOC>
<DOCNO> 9173 </DOCNO>
Spin Dynamics of Cavity Polaritons


  We have studied polariton spin dynamics in a GaAs/AlGaAs microcavity by means
of polarization- and time-resolved photoluminescence spectroscopy as a function
of excitation density and normal mode splitting. The experiments reveal a novel
behavior of the degree of polarization of the emission, namely the existence of
a finite delay to reach its maximum value. We have also found that the
stimulated emission of the lower polariton branch has a strong influence on
spin dynamics: in an interval of $\sim$150 ps the polarization changes from
+100% to negative values as high as -60%. This strong modulation of the
polarization and its high speed may open new possibilities for spin-based
devices.

</DOC>
<DOC>
<DOCNO> 169638 </DOCNO>
Noether Theorem and the quantum mechanical operators


  We show that the quantum mechanical momentum and angular momentum operators
are fixed by the Noether theorem for the classical Hamiltonian field theory we
proposed.

</DOC>
<DOC>
<DOCNO> 80705 </DOCNO>
The masses of the mesons and baryons. Part III. The size of the


  The size of the stable elementary particles is investigated with the standing
wave model. The particle size follows from the magnitude of the radiation
pressure. It is shown that the outward directed radiation pressure is balanced
by the inward directed elastic force per unit area in the cubic nuclear
lattice, provided that the sidelength of the lattice is 10^(-13) cm, which
agrees with the measured radius of the proton r = 0.8 \times 10^(-13) cm,
within the uncertainty of the parameters.

</DOC>
<DOC>
<DOCNO> 68613 </DOCNO>
Black Holes Radiate Mainly on the Brane


  We examine the evaporation of a small black hole on a brane in a world with
large extra dimensions. Since the masses of many Kaluza-Klein modes are much
smaller than the Hawking temperature of the black hole, it has been claimed
that most of the energy is radiated into these modes. We show that this is
incorrect. Most of the energy goes into the modes on the brane. This raises the
possibility of observing Hawking radiation in future high energy colliders if
there are large extra dimensions.

</DOC>
<DOC>
<DOCNO> 14139 </DOCNO>
Stability of Pareto-Zipf Law in Non-Stationary Economies


  Generalized Lotka-Volterra (GLV) models extending the (70 year old) logistic
equation to stochastic systems consisting of a multitude of competing
auto-catalytic components lead to power distribution laws of the (100 year old)
Pareto-Zipf type. In particular, when applied to economic systems, GLV leads to
power laws in the relative individual wealth distribution and in the market
returns. These power laws and their exponent alpha are invariant to arbitrary
variations in the total wealth of the system and to other endogenous and
exogenous factors. The measured value of the exponent alpha = 1.4 is related to
built-in human social and biological constraints.

</DOC>
<DOC>
<DOCNO> 121941 </DOCNO>
Power Spectra Estimation for Weak Lensing


  We develop a method for estimating the shear power spectra from weak lensing
observations and test it on simulated data. Our method describes the shear
field in terms of angular power spectra and cross correlation of the two shear
modes which differ under parity transformations. Two of the three power spectra
can be used to monitor unknown sources of noise in the data. The power spectra
are decomposed in a model independent manner in terms of ``band-powers'' which
are then extracted from the data using a quadratic estimator to find the
maximum of the likelihood and its local curvature (for error estimates). We
test the method against simulated data from Gaussian realizations and
cosmological N-body simulations. In the Gaussian case, the mean bandpowers and
their covariance are well recovered even for irregular (or sparsely) sampled
fields. The mild non-Gaussianity of the N-body realizations causes a slight
underestimation of the errors that becomes negligible for scales much larger
than several arcminutes and does not bias the recovered band powers.

</DOC>
<DOC>
<DOCNO> 69663 </DOCNO>
Gravitational Origin of Quark Masses and Mixings in an Extra-Dimensional


  Using the resolution of the gauge hierarchy problem recently proposed by
Randall and Sundrum, we find a natural explanation for the observed fermion
masses and mixings of the three Standard Model (SM) generations. Localizing
massless SM matter generations on neighboring 3-branes in an extra dimensional
world leads to effective four dimensional masses and mixings from the coupling
of the fermions with the background metric. We find that the positions of the
3-branes required to solve the gauge hierachy problem simultaneously reproduces
phenomenologically acceptable fermion masses and mixings.

</DOC>
<DOC>
<DOCNO> 116390 </DOCNO>
Bond breaking in vibrationally excited methane on transition metal


  The role of vibrational excitation of a single mode in the scattering of
methane is studied by wave packet simulations of oriented CH4 and CD4 molecules
from a flat surface. All nine internal vibrations are included. In the
translational energy range from 32 up to 128 kJ/mol we find that initial
vibrational excitations enhance the transfer of translational energy towards
vibrational energy and increase the accessibility of the entrance channel for
dissociation. Our simulations predict that initial vibrational excitations of
the asymmetrical stretch (nu_3) and especially the symmetrical stretch (nu_1)
modes will give the highest enhancement of the dissociation probability of
methane.

</DOC>
<DOC>
<DOCNO> 83267 </DOCNO>
An evaluation of Naive Bayesian anti-spam filtering


  It has recently been argued that a Naive Bayesian classifier can be used to
filter unsolicited bulk e-mail ("spam"). We conduct a thorough evaluation of
this proposal on a corpus that we make publicly available, contributing towards
standard benchmarks. At the same time we investigate the effect of
attribute-set size, training-corpus size, lemmatization, and stop-lists on the
filter's performance, issues that had not been previously explored. After
introducing appropriate cost-sensitive evaluation measures, we reach the
conclusion that additional safety nets are needed for the Naive Bayesian
anti-spam filter to be viable in practice.

</DOC>
<DOC>
<DOCNO> 10072 </DOCNO>
Temperature and Angular Dependence of the Magnetoresistance in Low


  Detailed studies of the magnetoresistance of alpha-(ET)2KHg(SCN)4 and
alpha-(ET)2TlHg(SCN)4 as a function of temperature, magnetic field strength,
and field orientation are reported. Below 15 K, the temperature dependence of
the magnetoresistance is metallic (dR/dT > 0) for magnetic field orientation
corresponding to an angular dependent magnetoresistance oscillation (AMRO)
minimum and nonmetallic (dR/dT < 0) at all other field orientations. We find
that this behavior can be explained in terms of semiclassical models without
the use of a non-Fermi liquid description. The alternating temperature
dependence (metallic/nonmetallic)with respect to field orientation is common to
any system with either quasi-one or two-dimensional AMRO. Furthermore, we
report a new metallic property of the high field and low temperature regime of
alpha-(ET)2MHg(SCN)4 (where M = K, Rb, or Tl) compounds.

</DOC>
<DOC>
<DOCNO> 121006 </DOCNO>
Topology of the Galaxy Distribution in the Hubble Deep Fields


  We have studied topology of the distribution of the high redshift galaxies
identified in the Hubble Deep Field (HDF) North and South. The two-dimensional
genus is measured from the projected distributions of the HDF galaxies at
angular scales from $3.8''$ to $ 6.1''$. We have also divided the samples into
three redshift slices with roughly equal number of galaxies using photometric
redshifts to see possible evolutionary effects on the topology.
  The genus curve of the HDF North clearly indicates clustering of galaxies
over the Poisson distribution while the clustering is somewhat weaker in the
HDF South. This clustering is mainly due to the nearer galaxies in the samples.
We have also found that the genus curve of galaxies in the HDF is consistent
with the Gaussian random phase distribution with no significant redshift
dependence.

</DOC>
<DOC>
<DOCNO> 12871 </DOCNO>
Large-n Limit of N=2 Supersymmetric Q^n Model in Two Dimensions


  We investigate non-perturbative structures of the two-dimensional N=2
supersymmetric nonlinear sigma model on the quadric surface Q^{n-2}(C) =
SO(n)/SO(n-2)xU(1), which is a Hermitian symmetric space, and therefore Kahler,
by using the auxiliary field and large-n methods. This model contains two kinds
of non-perturbatively stable vacua; one of them is the same vacuum as that of
supersymmetric CP^{n-1} model, and the other is a new kind of vacuum, which has
not yet been known to exist in two-dimensional nonlinear sigma models, the
Higgs phase. We show that both of these vacua are asymptotically free. Although
symmetries are broken in these vacua, there appear no massless Nambu-Goldstone
bosons, in agreement with Coleman's theorem, due to the existence of two
different mechanisms in these vacua, the Schwinger and the Higgs mechanisms.

</DOC>
<DOC>
<DOCNO> 14136 </DOCNO>
Symmetry of the remanent state flux distribution in superconducting thin


  The critical-state in a thin strip of YBaCuO is studied by magneto-optical
imaging. The distribution of magnetic flux density is shown to have a specific
symmetry in the remanent state after a large applied field. The symmetry was
predicted [PRL 82, 2947 (1999)] for any Jc(B), and is therefore suggested as a
simple tool to verify the applicability of the critical-state model. At large
temperatures we find deviations from this symmetry, which demonstrates
departure from the critical-state behavior. The observed deviations can be
attributed to an explicit coordinate dependence of $j_c$ since both a surface
barrier, and flux creep would break the symmetry in a different way.

</DOC>
<DOC>
<DOCNO> 69951 </DOCNO>
Reply to ``Is $U_{e3}$ really related to the solar neutrino solutions?''


  In a recent paper [1] we showed that, assuming no fine tuning between certain
elements of the neutrino mass matrix, one can link the element U_{e3} of the
lepton mixing matrix to solar and atmospheric neutrino oscillation parameters.
This result has been recently criticized by Haba and Suzuki [2]. In the present
note we show that their criticism is not valid and just reflects their failure
to understand the content of our paper.

</DOC>
<DOC>
<DOCNO> 68096 </DOCNO>
Can Four-fermion Contact Interactions at One-loop Explain the New Atomic


  We investigate the possibility that four-fermion contact interactions give
rise to the observed deviation from the Standard Model prediction for the weak
charge of Cesium, through one-loop contributions. We show that the presence of
loops involving the third generation quarks can explain such deviation.

</DOC>
<DOC>
<DOCNO> 83259 </DOCNO>
Novelty Detection for Robot Neotaxis


  The ability of a robot to detect and respond to changes in its environment is
potentially very useful, as it draws attention to new and potentially important
features. We describe an algorithm for learning to filter out previously
experienced stimuli to allow further concentration on novel features. The
algorithm uses a model of habituation, a biological process which causes a
decrement in response with repeated presentation. Experiments with a mobile
robot are presented in which the robot detects the most novel stimulus and
turns towards it (`neotaxis').

</DOC>
<DOC>
<DOCNO> 11793 </DOCNO>
Lee-Yang edge singularity in the three-dimensional Gross-Neveu model at


  We discuss the relevance of the Lee-Yang edge singularity to the
finite-temperature Z_2-symmetry restoration transition of the Gross-Neveu model
in three dimensions. We present an explicit result for its large-N free energy
density in terms of Zeta(3) and the absolute maximum of Clausen's function.

</DOC>
<DOC>
<DOCNO> 119647 </DOCNO>
Large Scale Pressure Fluctuations and Sunyaev-Zel'dovich Effect


  The Sunyaev-Zel'dovich (SZ) effect associated with pressure fluctuations of
the large scale structure gas distribution will be probed with current and
upcoming wide-field small angular scale cosmic microwave background
experiments. We study the generation of pressure fluctuations by baryons which
are present in virialized dark matter halos and by baryons present in small
overdensities. For collapsed halos, assuming the gas distribution is in
hydrostatic equilibrium with matter density distribution, we predict the
pressure power spectrum and bispectrum associated with the large scale
structure gas distribution by extending the dark matter halo approach which
describes the density field in terms of correlations between and within halos.
The projected pressure power spectrum allows a determination of the resulting
SZ power spectrum due to virialized structures. The unshocked photoionized
baryons present in smaller overdensities trace the Jeans-scale smoothed dark
matter distribution. They provide a lower limit to the SZ effect due to large
scale structure in the absence of massive collapsed halos. We extend our
calculations to discuss higher order statistics, such as bispectrum and
skewness in SZ data. The SZ-weak lensing cross-correlation is suggested as a
probe of correlations between dark matter and baryon density fields, while the
probability distribution functions of peak statistics of SZ halos in wide field
CMB data can be used as a probe of cosmology and non-Gaussian evolution of
large scale structure pressure fluctuations.

</DOC>
<DOC>
<DOCNO> 102242 </DOCNO>
Integrability, Seiberg-Witten Models and Picard-Fuchs Equations


  Expanded version of the author's contribution to the Concise Encyclopaedia of
Supersymmetry, eds. J. Bagger, S. Duplij and W. Siegel

</DOC>
<DOC>
<DOCNO> 71528 </DOCNO>
Double-diffractive processes in high-resolution missing-mass experiments


  We evaluate, in a model-independent way, the signal-to-background ratio for
Higgs -> b bbar detection in exclusive double-diffractive events at the
Tevatron and the LHC. For the missing-mass approach to be able to identify the
Higgs boson, it will be necessary to use a central jet detector and to tag b
quark jets. The signal is predicted to be very small at the Tevatron, but
observable at the LHC. However we note that the background, that is
double-diffractive dijet production, may serve as a unique gluon factory. We
also give estimates for the double-diffractive production of chi_c and chi_b
mesons at the Tevatron. We emphasize that a high-resolution missing-mass
measurement, on its own, is insufficient to identify rare processes.

</DOC>
<DOC>
<DOCNO> 69170 </DOCNO>
Probing the MSSM Higgs Boson Sector with Explicit CP Violation through


  We perform a systematic study of the production of a third-generation
fermion-pair, $\mu^+\mu^-\to f\bar{f}$ for $f=\tau^-,b$, and t in the minimal
supersymmetric standard model (MSSM) with explicit CP violation, which is
induced radiatively by soft trilinear interactions related to squarks of the
third generation. We classify all the observables for probing the CP property
of the Higgs bosons constructed by the initial muon beam polarization along
with the unpolarized final fermions and with the final-fermion polarization
configuration of equal helicity, respectively. The observables allow for
complete determination of CP property of the neutral Higgs bosons. The
interference between the Higgs boson and gauge boson contributions also could
provide a powerful method for the determination of the CP property of two heavy
Higgs bosons in the top-quark pair production near the energy region of the
Higgs-boson resonances. For the lightest Higgs-boson mass there is no sizable
interference between scalar and vector contributions for the determination of
the CP property of the lightest Higgs boson. We give a detailed numerical
analysis to show how the radiatively-induced CP violation in the Higgs sector
of the MSSM can be measured.

</DOC>
<DOC>
<DOCNO> 152067 </DOCNO>
Superstrings on AdS_5 x S^5 supertwistor space


  We derive the Green-Schwarz action on AdS_5 x S^5 using an alternate version
of the coset superspace construction. By Wick rotations and Lie algebra
identifications we bring the coset to GL(4|4)/(Sp(4) x GL(1))^2, which allows
us to represent the conformal transformations on unconstrained matrices. The
derivation is more streamlined even for the bosonic sector, and conformal
symmetry is manifest at every step. Kappa-symmetry gauge fixing is more
transparent.

</DOC>
<DOC>
<DOCNO> 117836 </DOCNO>
Magnetic Confinement, MHD Waves, and Smooth Line Profiles in AGN


  In this paper, we show that if the broad line region clouds are in
approximate energy equipartition between the magnetic field and gravity, as
hypothesized by Rees, there will be a significant effect on the shape and
smoothness of broad emission line profiles in active galactic nuclei. Line
widths of contributing clouds or flow elements are much wider than their
thermal widths, due to the presence of non-dissipative MHD waves, and their
collective contribution produce emission line profiles broader and smoother
than would be expected if a magnetic field were not present. As an
illustration, a simple model of isotropically emitting clouds, normally
distributed in velocity, is used to show that smoothness can be achieved for
less than 80,000 clouds and may even be as low as a few hundred. We conclude
that magnetic confinement has far reaching consequences for observing and
modeling active galactic nuclei.

</DOC>
<DOC>
<DOCNO> 14170 </DOCNO>
Exact velocity of dispersive flow in the asymmetric avalanche process


  Using the Bethe ansatz we obtain the exact solution for the one-dimensional
asymmetric avalanche process. We evaluate the velocity of dispersive flow as a
function of driving force and the density of particles. The obtained solution
shows a dynamical transition from intermittent to continuous flow.

</DOC>
<DOC>
<DOCNO> 71666 </DOCNO>
Three fermionic generations on a topological defect in extra dimensions


  We suggest a mechanism explaining the origin of three generations of the
Standard Model fermions from one generation in a higher-dimensional theory.
Four-dimensional fermions appear as zero modes trapped in the core of a
topological defect with topological number three. We discuss hierarchical
pattern of masses and mixings which arises in these models.

</DOC>
<DOC>
<DOCNO> 121023 </DOCNO>
The mass function of NGC288


  We present NICMOS NIC3 observations of the Galactic globular cluster NGC 288,
taken South - East at 2.4 times the cluster's half-light radius in the J and H
bands. We have detected the cluster main sequence down to J~25 and H~24. The
corresponding luminosity function covers the range 3<M_H<9 and peaks at
M_H~6.8. The theoretical tracks of Baraffe et al. (1997) at [Fe/H]=-1.3 give a
mass function which is best fitted by a log-normal distribution with
characteristic mass m_c=0.42 Msolar and a standard deviation sigma=0.35. This
result is fully consistent with the global mass function derived by Paresce &
De Marchi (2000) for a sample of 12 globular clusters with very different
dynamical histories, thus confirming that near the cluster's half-light radius
the mass function appears ``undistorted'' by evaporation or tidal interactions
with the Galaxy and should then reflect the initial mass function.

</DOC>
<DOC>
<DOCNO> 169674 </DOCNO>
Stochastic quantization of the dynamics of interacting qubit systems


  The dynamics of all states of a qubit system with arbitrary, even time
dependent, one qubit Hamiltonians and two qubit interactions is realized as one
and the same diffusion process for systems with time dependent statistical
weight in a space whose dimension grows only linearly with the number of
qubits. The ensuing Fokker-Planck equation for the corresponding nonpositive
probability density is equivalent to the von Neumann equation for the quantum
state. Presumably the effectiveness of the stochastic process as a numerical
quantization method decreases as the number of qubits grows.

</DOC>
<DOC>
<DOCNO> 71047 </DOCNO>
Heavy ion physics : theory


  Lattice quantum chromodynamics (QCD) predicts a new state of matter, called
quark-gluon plasma (QGP), at sufficiently high temperatures or equivalently
large energy densities. Relativistic heavy ion collisions are expected to
produce such energy densities, thereby providing us a chance to test the above
prediction. After a brief introduction of the necessary theoretical concepts, I
present some critical comments on the experimental results with an aim to
examine whether QGP has already been observed experimentally.

</DOC>
<DOC>
<DOCNO> 10856 </DOCNO>
Charge noise analysis of an AlGaAs/GaAs quantum dot using


  Radio-frequency (rf)- operated single-electron transistors (SETs) are
high-sensitivity, fast-response electrometers, which are valuable for
developing new insights into single-charge dynamics. We investigate
high-frequency (up to 1 MHz) charge noise in an AlGaAs/GaAs quantum dot using a
transmission-type rf-SET technique. The electron capture and emission kinetics
on a trap in the vicinity of the quantum dot are dominated by a Poisson
process. The maximum bandwidth for measuring single trapping events is about 1
MHz, which is the same as that required for observing single-electron tunneling
oscillations in a measurable current (~0.1pA).

</DOC>
<DOC>
<DOCNO> 121970 </DOCNO>
Dehydrogenation of polycyclic aromatic hydrocarbons in the diffuse


  We present a model for the hydrogenation states of Polycyclic Aromatic
Hydrocarbons (PAHs) in the diffuse interstellar medium. First, we study the
abundance of hydrogenation and charge states of PAHs due to photo-ionization,
photo-dissociation in the interstellar UV field, electron recombination and
chemical reactions between PAH cations and H or H_2. For PAH cations, we find
that the dehydrogenation effects are dominant. The hydrogenation state of PAHs
depends strongly on the H density, the size of the molecule and UV field. In
diffuse clouds with low H density and normal UV radiation, PAHs containing less
than 40 C are completely or strongly dehydrogenated whereas at high H density,
they are normally hydrogenated. The partially dehydrogenated species dominate
in intermediate density clouds. PAHs above 40 C are quite stable and are fully
hydrogenated, which would favor their spectroscopic search in near IR surveys
of Diffuse Interstellar Bands (DIBs).

</DOC>
<DOC>
<DOCNO> 72077 </DOCNO>
Resummation of Yukawa enhanced and subleading Sudakov logarithms in


  Future colliders will probe the electroweak theory at energies much larger
than the gauge boson masses. Large double (DL) and single (SL) logarithmic
virtual electroweak Sudakov corrections lead to significant effects for
observable cross sections. Recently, leading and subleading universal
corrections for external fermions and transverse gauge boson lines were
resummed by employing the infrared evolution equation method. The results were
confirmed at the DL level by explicit two loop calculations with the physical
Standard Model (SM) fields. Also for longitudinal degrees of freedom the
approach was utilized for DL-corrections via the Goldstone boson equivalence
theorem. In all cases, the electroweak Sudakov logarithms exponentiate. In this
paper we extend the same approach to both Yukawa enhanced as well as subleading
Sudakov corrections to longitudinal gauge boson and Higgs production. We use
virtual contributions to splitting functions of the appropriate Goldstone
bosons in the high energy regime and find that all universal subleading terms
exponentiate. The approach is verified by employing a non-Abelian version of
Gribov's factorization theorem and by explicit comparison with existing one
loop calculations. As a side result, we obtain also all top-Yukawa enhanced
subleading logarithms for chiral fermion production at high energies to all
orders. In all cases, the size of the subleading contributions at the two loop
level is non-negligible in the context of precision measurements at future
linear colliders.

</DOC>
<DOC>
<DOCNO> 120008 </DOCNO>
Detailed Analysis of Early to Late-Time Spectra of Supernova 1993J


  We present a detailed study of line structure in early to late-time spectra
of Supernova (SN) 1993J. Spectra during the nebular phase, but within the first
two years after explosion, exhibit small-scale structure in the emission lines
of some species, notably oxygen and magnesium, showing that the ejecta of SN
1993J are clumpy. On the other hand, a lack of structure in emission lines of
calcium implies that the source of calcium emission is uniformly distributed
throughout the ejecta. These results are interpreted as evidence that oxygen
emission originates in clumpy, newly synthesized material, while calcium
emission arises from material pre-existing in the atmosphere of the progenitor.
Spectra spanning the range 433-2454 days after the explosion show box-like
profiles for the emission lines, clearly indicating circumstellar interaction
in a roughly spherical shell. This is interpreted within the Chevalier &
Fransson (1994) model for SNe interacting with mass lost during prior stellar
winds. At very late times, the emission lines have a two-horned profile,
implying the formation of a somewhat flattened or disk-like structure that is a
significant source of emission. The very high signal-to-noise ratio spectra are
used to demonstrate the potential significance of misinterpretation of telluric
absorption lines in the spectra of bright SNe.

</DOC>
<DOC>
<DOCNO> 119744 </DOCNO>
Relativistic Corrections to the Sunyaev-Zel'dovich Effect for Clusters


  We extend the formalism for the calculation of the relativistic corrections
to the Sunyaev-Zel'dovich effect for clusters of galaxies and include the
multiple scattering effects. We present a systematic method for the inclusion
of the multiple scattering effects. The multiple scattering contribution is
found to be very small compared with the single scattering contribution. For
high-temperature galaxy clusters of k_{B}T_{e} = 15keV, the ratio of the both
contributions is -0.3% in the Wien region. In the Rayleigh--Jeans region the
ratio is -0.03%. Therefore the multiple scattering contribution is safely
neglected for the observed galaxy clusters.

</DOC>
<DOC>
<DOCNO> 84297 </DOCNO>
Gravitational Waves from Relativistic Stars


  Stellar pulsations in rotating relativistic stars are reviewed. Slow rotation
approximation is applied to solving the Einstein equations. The rotational
effects on the non-axisymmetric oscillations are explicitly shown in the polar
and axial modes.

</DOC>
<DOC>
<DOCNO> 150323 </DOCNO>
Tree Amplitudes and Linearized SUSY Invariants in D=11 Supergravity


  We exploit the tree level bosonic 4-particle scattering amplitudes in D=11
supergravity to construct the bosonic part of a linearized supersymmetry-,
coordinate- and gauge-invariant. By differentiation, this invariant can be
promoted to be the natural lowest (two-loop) order counterterm. Its existence
implies that the perturbative supersymmetry does not protect this ultimate
supergravity from infinities, given also the recently demonstrated divergence
of its 4-graviton amplitude.

</DOC>
<DOC>
<DOCNO> 71187 </DOCNO>
Searching for SUSY Dark Matter- The Directional Rate and the Modulation


  The detection of dark matter is central to particle physics and cosmology.
Current fashionable supersymmetric models provide a dark matter candidate, the
lightest supersymmetric particle (LSP). When combined with fairly well
understood physics (quark structure of the nucleon and some nuclear structure,
they yield direct event rates. The obtained rates are, however, very low. So we
exploit characteristic signatures, like the modulation effect, i.e. the
dependence of the rate on the earth's annual motion, and the directional rate,
i.e its dependence on the direction of the recoiling nucleus, employing various
velocity distributions, isothermal (symmetric and axially asymmetric) and non
isothermal (due to to caustic rings).

</DOC>
<DOC>
<DOCNO> 13854 </DOCNO>
Landau diamagnetism and magnetization of interacting diffusive


  We show how the orbital magnetization of an interacting disordered diffusive
electron gas can be simply related to the magnetization of the non-interacting
system having the same geometry. This result is applied to the persistent
current of a mesoscopic ring and to the relation between Landau diamagnetism
and the interaction correction to the magnetization of diffusive systems. The
field dependence of this interaction contribution can be deduced directly from
the de Haas-van Alphen oscillations of the free electron gas. Known results for
the free orbital magnetism of finite systems can be used to derive the
interaction contribution in the diffusive regime in various geometries.

</DOC>
<DOC>
<DOCNO> 70060 </DOCNO>
Physics of Dense and Superdense Matter


  I discuss a few aspects of dense hadronic matter and superdense QCD matter
that are considered to be relevant to the physics of compact astrophysical
systems. The connection between a "bottom-up approach" and a "top-down
approach" is made with the help of an effective field theory strategy. Topics
treated are meson condensation going up from low density and color
superconductivity going down from asymptotic density with the approach to the
chiral phase transition made in terms of Brown-Rho scaling.

</DOC>
<DOC>
<DOCNO> 116402 </DOCNO>
Electron-Ion Recombination Rate Coefficients and Photoionization Cross


  The first complete set of unified cross sections and rate coefficients are
calculated for photoionization and recombination of He- and Li-like ions using
the relativistic Breit-Pauli R-matrix method. We present total, unified (e +
ion) recombination rate coefficients for (e + C VI ---> C V) and (e + C V
\longrightarrow C IV) including fine structure. Level-specific recombination
rate coefficients up to the n = 10 levels are also obtained for the first time;
these differ considerably from the approximate rates currently available.
Applications to recombination-cascade coefficients in X-ray spectral models of
K-alpha emission from the important He-like ions is pointed out. The overall
uncertainty in the total recombination rates should not exceed 10-20%.
Ionization fractions for Carbon are recomputed in the coronal approximation
using the new rates.
 The present (e + ion) recombination rate coefficients are compared with
several sets of available data, including previous LS coupling results, and
`experimentally derived' rate coefficients. The role of relativistic fine
structure, resolution of resonances, radiation damping, and interference
effects is discussed. Two general features of recombination rates are noted:
(i) the non-resonant (radiative recombination) peak as E,T ---> 0, and the (ii)
the high-T resonant (di-electronic recombination) peak.

</DOC>
<DOC>
<DOCNO> 71946 </DOCNO>
Coordinate Space Distributions of Antiquark Flavor Asymmetries in the


  We examine the space-time properties of the distribution (dbar - ubar) and
dbar/ubar in the proton. The difference of the antiquark distributions shows
the expected peak at the approximate pion Compton wavelength and is
supportative of the thesis that the meson cloud of the nucleon is at the origin
of the asymmetry of (dbar - ubar), with the pion cloud playing a dominant role.

</DOC>
<DOC>
<DOCNO> 102478 </DOCNO>
The Eigenvectors of the Right-Justified Pascal Triangle: A Shorter Proof


  Instead of dealing with cumbersome binomial identities, we prove Callan's
result using generating functions.

</DOC>
<DOC>
<DOCNO> 84904 </DOCNO>
Charge conservation and time-varying speed of light


  It has been recently claimed that cosmologies with time dependent speed of
light might solve some of the problems of the standard cosmological scenario,
as well as inflationary scenarios. In this letter we show that most of these
models, when analyzed in a consistent way, lead to large violations of charge
conservation. Thus, they are severly constrained by experiment, including those
where $c$ is a power of the scale factor and those whose source term is the
trace of the energy-momentum tensor. In addition, early Universe scenarios with
a sudden change of $c$ related to baryogenesis are discarded.

</DOC>
<DOC>
<DOCNO> 122850 </DOCNO>
The Seyfert-Starburst Connection in X-rays. I. The Data


  We analyze X-ray spectra and images of a sample of Seyfert 2 galaxies that
unambiguously contain starbursts, based on their optical and UV
characteristics. Although all sample members contain active galactic nuclei
(AGNs), supermassive black holes or other related processes at the galactic
centers alone cannot account for the total X-ray emission in all instances.
Eleven of the twelve observed galaxies are significantly resolved with the
ROSAT HRI, while six of the eight sources observed with the lower-resolution
PSPC also appear extended on larger scales. The X-ray emission is extended on
physical scales of 10 kpc and greater, which we attribute to starburst-driven
outflows and supernova-heating of the interstellar medium. Spectrally, a
physically-motivated composite model of the X-ray emission that includes a
heavily absorbed (N_H > 10^{23} cm^{-2}) nuclear component (the AGN), power-law
like scattered AGN flux, and a thermal starburst describes this sample well.
Half the sample exhibit iron K alpha lines, which are typical of AGNs.

</DOC>
<DOC>
<DOCNO> 70029 </DOCNO>
Influence of nucleonic motion in Relativistic Fermi Gas inclusive


  Impulsive hadronic descriptions of electroweak processes in nuclei involve
two distinctly different elements: one stems from the nuclear many-body physics
--- the medium --- which is rather similar for the various inclusive response
functions, and the other embodies the responses of the hadrons themselves to
the electroweak probe and varies with the channel selected. In this letter we
investigate within the context of the relativistic Fermi gas in both the
quasi-elastic and $N\to\Delta$ regimes the interplay between these two
elements. Specifically, we focus on expansions in the one small parameter in
the problem, namely, the momentum of a nucleon in the initial wave function
compared with the hadronic scale, the nucleon mass. Both parity-conserving and
-violating inclusive responses are studied and the interplay between
longitudinal ($L$) and transverse ($T$ and $T'$) contributions is highlighted.

</DOC>
<DOC>
<DOCNO> 100981 </DOCNO>
The complex Sine-Gordon equation as a symmetry flow of the AKNS


  It is shown how the complex sine-Gordon equation arises as a symmetry flow of
the AKNS hierarchy. The AKNS hierarchy is extended by the ``negative'' symmetry
flows forming the Borel loop algebra. The complex sine-Gordon and the vector
Nonlinear Schrodinger equations appear as lowest negative and second positive
flows within the extended hierarchy. This is fully analogous to the well-known
connection between the sine-Gordon and mKdV equations within the extended mKdV
hierarchy.
  A general formalism for a Toda-like symmetry occupying the ``negative''
sector of sl(N) constrained KP hierarchy and giving rise to the negative Borel
sl(N) loop algebra is indicated.

</DOC>
<DOC>
<DOCNO> 117078 </DOCNO>
Charged-Surface Instability Development in Liquid Helium; Exact


  The nonlinear dynamics of charged-surface instability development was
investigated for liquid helium far above the critical point. It is found that,
if the surface charge completely screens the field above the surface, the
equations of three-dimensional (3D) potential motion of a fluid are reduced to
the well-known equations describing the 3D Laplacian growth process. The
integrability of these equations in 2D geometry allows the analytic description
of the free-surface evolution up to the formation of cuspidal singularities at
the surface.

</DOC>
<DOC>
<DOCNO> 8506 </DOCNO>
A comparison between broad histogram and multicanonical methods


  We discuss the conceptual differences between the Broad Histogram (BHM) and
reweighting methods in general, and particularly the so-called Multicanonical
(MUCA) approaches. The main difference is that BHM is based on microcanonical,
fixed-energy averages which depends only on the good statistics taken {\bf
inside} each energy level. The detailed distribution of visits among different
energy levels, determined by the particular dynamic rule one adopts, is
irrelevant. Contrary to MUCA, where the results are extracted from the dynamic
rule itself, within BHM any microcanonical dynamics could be adopted. As a
numerical test, we have used both BHM and MUCA in order to obtain the spectral
energy degeneracy of the Ising model in $4 \times 4 \times 4$ and $32 \times
32$ lattices, for which exact results are known. We discuss why BHM gives more
accurate results than MUCA, even using {\bf the same} Markovian sequence of
states. In addition, such advantage increases for larger systems.

</DOC>
<DOC>
<DOCNO> 120286 </DOCNO>
Phase Dependent Spectroscopy of Mira Variable Stars


  Spectroscopic measurements of Mira variable stars, as a function of phase,
probe the stellar atmospheres and underlying pulsation mechanisms. For example,
measuring variations in TiO, VO, and ZrO with phase can be used to help
determine whether these molecular species are produced in an extended region
above the layers where Balmer line emission occurs or below this shocked
region. Using the same methods, the Balmer-line increment, where the strongest
Balmer line at phase zero is H-delta and not H-alpha can be measured and
explanations tested, along with another peculiarity, the absence of the
H-epsilon line in the spectra of Miras when other Balmer lines are strong. We
present new spectra covering the spectral range from 6200 Angstroms to 9000
Angstroms of 20 Mira variables. A relationship between variations in the CaII
IR triplet and H-alpha as a function of phase support the hypothesis that
H-epsilon's observational characteristics result from an interaction of
H-epsilon photons with the CaII H line. New periods and epochs of variability
are also presented for each star.

</DOC>
<DOC>
<DOCNO> 68869 </DOCNO>
How to Integrate Divergent Integrals: a Pure Numerical Approach to


  Loop calculations involve the evaluation of divergent integrals.
  Usually [1] one computes them in a number of dimensions different than four
where the integral is convergent and then one performs the analytical
continuation and considers the Laurent expansion in powers of epsilon =n-4. In
this paper we discuss a method to extract directly all coefficients of this
expansion by means of concrete and well defined integrals in a five dimensional
space. We by-pass the formal and symbolic procedure of analytic continuation;
instead we can numerically compute the integrals to extract directly both the
coefficient of the pole 1/epsilon and the finite part.

</DOC>
<DOC>
<DOCNO> 178942 </DOCNO>
Chiral approach to the rho meson in nuclear matter


  In this work, the properties of the $\rho$ meson at rest in cold symmetric
nuclear matter are studied. We make use of a chiral unitary approach to
pion-pion scattering in the vector-isovector channel, calculated from the
lowest order Chiral Perturbation Theory ($\chi PT$) lagrangian including
explicit resonance fields. Low energy chiral constraints are considered by
matching our expressions to those of one loop $\chi PT$. To account for the
medium corrections, the $\rho$ couples to $\pi\pi$ pairs which are properly
renormalized in the nuclear medium, accounting for both $p-h$ and $\Delta -h$
excitations. The terms where the $\rho$ couples directly to the hadrons in the
$p-h$ or $\Delta -h$ excitations are also accounted for. In addition, the
$\rho$ is also allowed to couple to $N^{*}(1520)-h$ components.

</DOC>
<DOC>
<DOCNO> 13895 </DOCNO>
Comb-like polymers inside nanoscale pores


  A new method of polymer characterization, based on permeation studies using
nanoscale pores, was recently proposed by Brochard and de Gennes. In the
present paper, we study how this method, initially developped for star polymers
can be extended to comb-like polymers.

</DOC>
<DOC>
<DOCNO> 72119 </DOCNO>
On the chaoticity of active-sterile neutrino oscillations in the early


  We have investigated the evolution of the neutrino asymmetry in
active-sterile neutrino oscillations in the early universe. We find that there
are large regions of parameter space where the asymmetry is extremely sensitive
to variations in the initial asymmetry as well as the external parameters (the
mass difference and the mixing angle). In these regions the system undergoes
chaotic transitions; however, the system is never truly chaotic in the sense
that all information about initial conditions is lost. In some cases though,
enough information is lost that the final sign of the neutrino asymmetry is
stochastic. We discuss the implications of our findings for Big Bang
nucleosynthesis (BBN) and the cosmic microwave background (CMB).

</DOC>
<DOC>
<DOCNO> 13586 </DOCNO>
Phase Diagram of the Hubbard Model: Beyond the Dynamical Mean Field


  The Dynamical Cluster Approximation (DCA) is used to study non-local
corrections to the dynamical mean field phase diagram of the two-dimensional
Hubbard model. Regions of antiferromagnetic, d-wave superconducting,
pseudo-gapped non-Fermi liquid, and Fermi liquid behaviors are found, in rough
agreement with the generic phase diagram of the cuprates. The non-local
fluctuations beyond the mean field both suppress the antiferromagnetism and
mediate the superconductivity.

</DOC>
<DOC>
<DOCNO> 116709 </DOCNO>
Plasma Oscillations and Expansion of an Ultracold Neutral Plasma


  We report the observation of plasma oscillations in an ultracold neutral
plasma. With this collective mode we probe the electron density distribution
and study the expansion of the plasma as a function of time. For classical
plasma conditions, i.e. weak Coulomb coupling, the expansion is dominated by
the pressure of the electron gas and is described by a hydrodynamic model.
Discrepancies between the model and observations at low temperature and high
density may be due to strong coupling of the electrons.

</DOC>
<DOC>
<DOCNO> 119098 </DOCNO>
Current status of cosmological MDM model


  An analysis of cosmological models in spatially flat Friedmann Universe with
cosmic gravitational wave background and zero $\Lambda$-term is presented. The
number of free parameters is equal to 5, they are $\sigma_8$, $n$,
$\Omega_\nu$, $\Omega_b$, and $h$. The normalization of the spectrum of density
perturbations on galaxy cluster abundance ($\sigma_8 = 0.52\pm 0.04$) has been
used to calculate numerically the value of the large scale CMB anisotropy
($\ell\simeq 10$) and the relative contribution of cosmological gravitational
waves T/S. Increasing $\Omega_\nu$ weaken the requirements to the value of T/S,
however even for $\Omega_\nu\le 0.4$ the models with $h+n\ge 1.5$ suggest
considerable abundance of gravitational waves: T/S${}^>_\sim 0.3$. In models
with $\Omega_\nu\le 0.4$ and scale-invariant spectrum of density perturbations
($n=1$): T/S${}^>_\sim 10(h-0.47)$. Minimization of the value T/S is possible
only in the range of the red spectra ($n<1$) and small $h$ ($<0.6$). It is
shown that the models with T/S$\in [0, 3]$ admit both moderate red and blue
spectra of density perturbations, $n\in[0.9,1.2]$, with rather high abundance
hot dark matter, $\Omega_\nu\in [0.2,0.4]$. Any condition, $n<0.9$ or
$\Omega_\nu<0.2$, decreases the relative amplitude of the first acoustic peak
for more than 30% in comparison with its hight in the standard CDM normalized
by COBE data.

</DOC>
<DOC>
<DOCNO> 9052 </DOCNO>
Conductance modulation by spin precession in non-collinear


  We study diffusive transport through ferromagnet - normal metal - ferromagnet
(F-N-F) systems, with arbitrary but fixed magnetization directions of the
ferromagnetic reservoirs and orientations of a magnetic field applied to the
normal metal. For non-collinear configurations, the complex mixing conductance
describes the transport of spins non-collinear to the magnetizations of the
ferromagnetic reservoirs. When the imaginary part of the mixing conductance is
different from zero, the total conductance of the system in the presence of a
magnetic field can be asymmetric with respect to time reversal. The total
conductance changes non-monotonically with the magnetic field strength for
different magnetic configurations. This modulation of the conductance is due to
the precession of the spin accumulation in the normal metal. The difference
between the conductance of the parallel and antiparallel configurations can be
either positive or negative as a function of the applied magnetic field. This
effect should be best observable on Al single crystals attached to
ferromagnetic electrodes by means of tunnel junctions or metallic contacts.

</DOC>
<DOC>
<DOCNO> 68112 </DOCNO>
Toward Chiral Theory of NN interactions in nuclear matter


  The effective chiral theory of the in-medium NN interactions is considered.
 The shallow bound states, which complicate the effective field theory analysis
in vacuum do not exist in matter. We show that the next-to-leading order terms
in the chiral expansion of the effective Lagrangian can be interpreted as
corrections so that the expansion is systematic. The Low Energy Effective
Constants of this Lagrangian are found to satisfy the concept of naturalness.
The potential energy per particle is calculated. The problems and challenges in
constructing the chiral theory of nuclear matter are outlined.

</DOC>
<DOC>
<DOCNO> 151020 </DOCNO>
String from Large N Gauge Fields via Graph Summation on a P+ - x+


  I describe renewed efforts to establish a string description of large N_c QCD
by summing large ``fishnet'' diagrams. Earlier work on fishnets indicated that
the usual relativistic (zero thickness) string theory can arise at strong 't
Hooft coupling, at best yielding a highly idealized description, which fails to
incorporate such salient features of continuum QCD as asymptotic freedom and
point-like constituents. The recently conjectured AdS/CFT correspondence is
compatible with such limitations because it also gives a simple picture of
large N_c gauge theory only at strong coupling. In order to better understand
how string theory could emerge from large N_c QCD at strong coupling, Klaus
Bering, Joel Rozowsky, and I have developed an improved implementation of my
effort of the late seventies to digitize the planar diagrams of large N_c
light-cone quantized QCD by discretizing both P+ and x+. This discretization
allows a strong coupling limit of the sum of planar diagrams to be defined and
studied. It also provides a natural framework to explore the possible dual
relationship between QCD in light-cone gauge and string theory quantized on the
light-cone.

</DOC>
<DOC>
<DOCNO> 120925 </DOCNO>
The Extreme Scattering Event Toward 1741-038: H I Absorption


  We report multi-epoch VLA H I absorption observations of the source 1741-038
(OT-068) before and during an extreme scattering event (ESE). Observations at
four epochs, three during the ESE, were obtained. We find no changes in the
equivalent width, maximum optical depth, or velocity of maximum optical depth
during the ESE, but we do find a secular trend of decreasing maximum optical
depth between our observations and ones by other observers a decade prior. The
resulting limit on the H I column density change during the ESE for a structure
with a spin temperature T_s is 6.4 x 10^{17} cm^{-2} (T_s/10 K). Tiny-scale
atomic structures (TSAS), with a column density N_H ~ 3 x 10^{18} cm^{-2}, are
ruled out marginally by this limit, though geometric arguments may allow this
limit to be relaxed. Galactic halo molecular clouds, that are opaque in the H I
line, cannot be excluded because the observed velocity range covers only 25% of
their allowed velocity range.

</DOC>
<DOC>
<DOCNO> 122185 </DOCNO>
Introductory Remarks on The Extragalactic Infrared Background and its


  I review the assumptions and observations that motivate the concept of the
extragalactic cosmic background radiation, and the issues of energy accounts
and star formation history as a function of galaxy morphological type that
figure in the interpretation of the measurements of the extragalactic infrared
background.

</DOC>
<DOC>
<DOCNO> 69088 </DOCNO>
Resonant decay of parity odd bubbles in hot hadronic matter


  We investigate the decay of metastable states with broken CP-symmetry which
have recently been proposed by Kharzeev, Pisarski and Tytgat to form in hot
hadronic matter. We consider the efficiency of the amplification of the
$\eta'$-field via parametric resonance, taking the backreaction into account.
For times of the order $t\approx 10 fm$, we find a particle density of about
$0.7/fm^3$ and a correlation length of $\xi_{max}\approx 2.5 fm$. The
corresponding momentum spectra show a non-thermal behaviour.

</DOC>
<DOC>
<DOCNO> 69063 </DOCNO>
$D^*D\pi$ and $B^*B\pi$ form factors from QCD Sum Rules


  The $H^*H\pi$ form factor for H = B and D mesons is evaluated in a QCD sum
rule calculation. We study the Borel sum rule for the three point function of
two pseudoscalar and one vector meson currents up to order four in the operator
product expansion. The double Borel transform is performed with respect to the
heavy meson momenta. We discuss the momentum dependence of the form factors and
two different approaches to extract the $H^*H\pi$ coupling constant.

</DOC>
<DOC>
<DOCNO> 99849 </DOCNO>
Frobenius-Schur functions: summary of results


  We introduce and study a family of inhomogeneous symmetric functions which we
call the Frobenius-Schur functions. These functions are indexed by partitions
and differ from the conventional Schur functions in lower terms only.
  Our interest in these new functions comes from the fact that they provide an
explicit expression for the dimension of a skew Young diagram in terms of the
Frobenius coordinates. This is important for the asymptotic theory of the
characters of the symmetric groups.
  Our main result is a surprisingly simple determinantal expression of the
Frobenius-Schur functions in terms of the conventional Schur functions. Other
results include certain generating series, the Giambelli formula, vanishing
properties and interpolation, a combinatorial formula (representation in terms
of tableaux), and a Sergeev-Pragacz-type formula.
  Actually, we deal with a wider class of inhomogeneous symmetric functions
which we call multiparameter Schur functions. These functions depend on an
arbitrary doubly infinite sequence of parameters and interpolate between the
Frobenius--Schur functions and the conventional Schur functions.
  This paper contains the statements of the results and the main formulas.
Proofs will be given in an expanded version of the paper which will be posted
in the arXiv.

</DOC>
<DOC>
<DOCNO> 150880 </DOCNO>
A Test of the AdS/CFT Duality on the Coulomb Branch


  We consider the N=4 SU(N) Super Yang Mills theory on the Coulomb branch with
gauge symmetry broken to S(U(N_1) x U(N_2)). By integrating the W particles,
the effective action near the IR SU(N_i) conformal fixed points is seen to be a
deformation of the Super Yang Mills theory by a non-renormalized, irrelevant,
dimension 8 operator. The correction to the two-point function of the dilaton
field dual operator near the IR is related to a three-point function of chiral
primary operators at the conformal fixed points and agrees with the classical
gravity prediction, including the numerical factor.

</DOC>
<DOC>
<DOCNO> 121078 </DOCNO>
Radio identification of decametric sources. I. Catalogue


  We describe a method of plotting continuous spectra for radio sources on the
basis of entries of various source catalogues in comparatively large error
boxes around a given sky position. Sources from the UTR-2 catalogue (Braude et
al., 1978, 1979, 1981, 1985, 1994), observed at decametric wavelengths (10--25
MHz) with an antenna beam of about 40', were cross-identified with entries from
other radio catalogues at higher frequencies. Using the CATS database we
extracted all sources within 40' around UTR positions to find candidate
identifications. The spectrum for each source was fitted with a set of curves
using the least squares method to find the best fit. We preferentially selected
radio counterparts whose radio spectrum extrapolated to low frequencies matched
the UTR decametric flux densities, and whose coordinates were close to the
gravity centre of UTR positions. Among all 1822 sources in the UTR catalogue we
found about 350 sources to be blends of two or more sources. As the most
probable true coordinates of the radio counterparts we used positions from the
FIRST, NVSS, TXS, GB6, or PMN catalogues. Using low-frequency sources (26, 38,
85 MHz) from CATS we checked the reliability of some of our identifications. We
show examples `of the above methods, including raw and ``cleaned'' spectra.
Identifications with objects from optical, X-ray and infrared catalogues, as
well as a subsample of UTR sources with ultra-steep spectrum are presented.

</DOC>
<DOC>
<DOCNO> 151876 </DOCNO>
Partition Sums and Entropy Bounds in Weakly Coupled CFT


  We use the partition functions on S^1 x S^n of various conformal field
theories in four and six dimensions in the limit of vanishing coupling to study
the high temperature thermodynamics. Certain modular properties exhibited by
the partition functions help to determine the finite volume corrections, which
play a role in the discussion of entropy bounds.

</DOC>
<DOC>
<DOCNO> 71088 </DOCNO>
The Spectrum of Diquark Composites in Cold Dense QCD


  The Bethe-Salpeter equations for spin zero diquark composites in the color
superconducting phase of $N_f=2$ and $N_f=3$ cold dense QCD are studied. The
explicit form of the spectrum of the diquarks with the quantum numbers of the
(pseudo-) Nambu-Goldstone bosons is derived.

</DOC>
<DOC>
<DOCNO> 12093 </DOCNO>
Resistance effects due to magnetic guiding orbits


  The Hall and magnetoresistance of a two dimensional electron gas subjected to
a magnetic field barrier parallel to the current direction is studied as
function of the applied perpendicular magnetic field. The recent experimental
results of Nogaret {\em et al.} [Phys. Rev. Lett. {\bf 84}, 2231 (2000)] for
the magneto- and Hall resistance are explained using a semi-classical theory
based on the Landauer-B\"{u}ttiker formula. The observed positive
magnetoresistance peak is explained as due to a competition between a decrease
of the number of conducting channels as a result of the growing magnetic field,
from the fringe field of the ferromagnetic stripe as it becomes magnetized, and
the disappearance of snake orbits and the subsequent appearance of cycloidlike
orbits.

</DOC>
<DOC>
<DOCNO> 121752 </DOCNO>
Galaxy number counts - V. Ultra-deep counts: The Herschel and Hubble


  We present u,b,r & i galaxy number counts and colours both from the North and
South Hubble Space Telescope Deep Fields and from the William Herschel Deep
Field. The latter comprises a 7'x7' area of sky reaching b~28.5 at its deepest.
We show that simple Bruzual & Charlot evolutionary models which assume
exponentially increasing star-formation rates with look-back time and q_0=0.05
continue to give excellent fits to galaxy counts and colours in the deep
imaging data. With q_0=0.5, an extra population of `disappearing dwarf'
galaxies is required to fit the optical counts. When we compare the observed
and predicted galaxy counts for UV dropouts in the range 2<z<3.5 we find
excellent agreement, indicating that the space density of galaxies may not have
changed much since z=0 and identifying the Lyman break galaxies with the bright
end of the evolved spiral luminosity function. Making the same comparison for B
dropout galaxies in the range 3.5<z<4.5 we find that the space density of
intrinsically bright galaxies remains the same but the space density of faint
galaxies drops by a factor of ~5 compared to the models, consistent with the
idea that L* galaxies were already in place at z~4 but that dwarf galaxies may
have formed later at 3<z<4.

</DOC>
<DOC>
<DOCNO> 118120 </DOCNO>
The Detectability of Gamma-Ray Bursts and Their Afterglows at Very High


  There is increasingly strong evidence that gamma-ray bursts (GRBs) are
associated with star-forming galaxies, and occur near or in the star-forming
regions of these galaxies. These associations provide indirect evidence that at
least the long GRBs detected by BeppoSAX are a result of the collapse of
massive stars. The recent evidence that the light curves and the spectra of the
afterglows of GRB 970228 and GRB 980326 appear to contain a supernova
component, in addition to a relativistic shock wave component, provide more
direct clues that this is the case. Here we establish that GRBs and their
afterglows are both detectable out to very high redshifts (z > 5).

</DOC>
<DOC>
<DOCNO> 120328 </DOCNO>
The W4 chimney/superbubble


  A conical void in the Galactic HI within the Perseus arm has been proposed to
be a chimney. However, Halpha data suggest that the structure may be closed at
higher latitudes and therefore is a superbubble rather than a chimney. Recent
observations have extended our view of the HI and the radio continuum emission
to higher latitudes, up to 8 degrees;. The new images show the HI structure to
be open at the top and a small filament suggests recent breakout. The conical
shape of the structure is not easily explained by superbubble models.

</DOC>
<DOC>
<DOCNO> 120625 </DOCNO>
Imaging Performance of the XMM-Newton X-ray telescopes


  The in-orbit imaging performance of the three X-ray telescopes on board of
the X-ray astronomy observatory XMM-Newton is presented and compared with the
performance measured on ground at the MPE PANTER test facility. The comparison
shows an excellent agreement between the on ground and in-orbit performance.

</DOC>
<DOC>
<DOCNO> 8609 </DOCNO>
Geometrical phase effects in biaxial nanomagentic particles


  The oscillation of tunnel splitting are obtained by geometrical analysis of
the topological Wess-Zumino phase on the basis of tunneling paths in biaxial
nanomagnetic particles with magnetic field along the hard anisotropy axis. This
theory not only just yields the previous quantum interference results for the
ground state tunneling, but also gives the excited level splittings, all of
which agree well with the numerical diagonalization. Furthermore, the parity
effect in the asymmetric system which was recently discovered in experiment can
be derived by similar arguments, and is also certified by using the complex
periodic orbit theory. The possibility of improving the discrepancy with the
experiment in the periods of oscillations is discussed.

</DOC>
<DOC>
<DOCNO> 121719 </DOCNO>
Standard Cosmic Ray Energetics and Light Element Production


  The recent observations of Be and B in metal poor stars has led to a
reassessment of the origin of the light elements in the early Galaxy. At low it
is metallicity ([O/H] < -1.75), it is necessary to introduce a production
mechanism which is independent of the interstellar metallicity (primary). At
higher metallicities, existing data might indicate that secondary production is
dominant. In this paper, we focus on the secondary process, related to the
standard Galactic cosmic rays, and we examine the cosmic ray energy
requirements for both present and past epochs. We find the power input to
maintain the present-day Galactic cosmic ray flux is about 1.5e41 erg/s = 5e50
erg/century. This implies that, if supernovae are the sites of cosmic ray
acceleration, the fraction of explosion energy going to accelerated particles
is about 30%, a value which we obtain consistently both from considering the
present cosmic ray flux and confinement and from the present 9Be and 6Li
abundances. Using the abundances of 9Be (and 6Li) in metal-poor halo stars, we
extend the analysis to show the effect of the interstellar gas mass on the
standard galactic cosmic ray energetic constraints on models of Li, Be, and B
evolution. The efficiency of the beryllium production per erg may be enhanced
in the past by a factor of about 10; thus the energetic requirement by itself
cannot be used to rule out a secondary origin of light elements. Only a clear
and undisputable observational determination of the O-Fe relation in the halo
will discriminate between the two processes. (abridged)

</DOC>
<DOC>
<DOCNO> 101429 </DOCNO>
On the spectrum of Dehn twists in quantum Teichmuller theory


  The operator realizing a Dehn twist in quantum Teichmuller theory is
diagonalized and continuous spectrum is obtained. This result is in agreement
with the expected spectrum of conformal weights in quantum Liouville theory at
c>1. The completeness condition of the eigenvectors includes the integration
measure which appeared in the representation theoretic approach to quantum
Liouville theory by Ponsot and Teschner. The underlying quantum group structure
is also revealed.

</DOC>
<DOC>
<DOCNO> 169808 </DOCNO>
Speed of ion trap quantum information processors


  We investigate theoretically the speed limit of quantum gate operations for
ion trap quantum information processors. The proposed methods use laser pulses
for quantum gates which entangle the electronic and vibrational degrees of
freedom of the trapped ions. Two of these methods are studied in detail and for
both of them the speed is limited by a combination of the recoil frequency of
the relevant electronic transition, and the vibrational frequency in the trap.
We have experimentally studied the gate operations below and above this speed
limit. In the latter case, the fidelity is reduced, in agreement with our
theoretical findings. //
  Changes: a) error in equ. 24 and table III repaired b) reference Jonathan et
al, quant-ph/ 0002092, added (proposes fast quantum gates using the AC-Stark
effect)

</DOC>
<DOC>
<DOCNO> 152416 </DOCNO>
Clifford Algebra Based Polydimensional Relativity and Relativistic


  Starting from the geometric calculus based on Clifford algebra, the idea that
physical quantities are Clifford aggregates ("polyvectors") is explored. A
generalized point particle action ("polyvector action") is proposed. It is
shown that the polyvector action, because of the presence of a scalar (more
precisely a pseudoscalar) variable, can be reduced to the well known,
unconstrained, Stueckelberg action which involves an invariant evolution
parameter. It is pointed out that, starting from a different direction, DeWitt
and Rovelli postulated the existence of a clock variable attached to particles
which serve as a reference system for identification of spacetime points. The
action they postulated is equivalent to the polyvector action. Relativistic
dynamics (with an invariant evolution parameter) is thus shown to be based on
even stronger theoretical and conceptual foundations than usually believed.

</DOC>
<DOC>
<DOCNO> 12589 </DOCNO>
Unzipping DNA : A hypothesis on correlation during replication


  Based on the result of an unzipping phase transition by a force in a model of
DNA, we hypothesize that the DnaA-type proteins act as a pulling agent with a
force slightly less than the critical force for unzipping. The dynamic
(space-time) correlation of unzipping then drives the subsequent events of
replication. In such a correlation driven scenario, there is no need of a
replisome as a structural unit and this elusive replisome may not exist at all.

</DOC>
<DOC>
<DOCNO> 170283 </DOCNO>
A simple proof of the unconditional security of relativistic quantum


  A simple proof of the unconditional security of a relativistic quantum
cryptosystem based on orthogonal states is proposed. Restrictions imposed by
special relativity allow to substantially simplify the proof compared with the
non-relativistic cryptosystems involving non-orthogonal states. Important for
the proposed protocol is the spatio-temporal structure of the quantum states
which is actually ignored in the non-relativistic protocols employing only the
structure of the state space of the information carriers. As a consequence, the
simplification arises because of the inefficiency of collective measurements
which constitute the major problem in the non-relativistic case.

</DOC>
<DOC>
<DOCNO> 116698 </DOCNO>
The problem of friction in two-dimensional relative motion


  We analyse a mechanical system in two-dimensional relative motion with
friction. Although the system is simple, the peculiar interplay between two
kinetic friction forces and gravity leads to the wide range of admissible
solutions exceeding most intuitive expectations. In particular, the strong
qualitative dependence between behaviour of the system, boundary conditions and
parameters involved in its description is emphasised. The problem is intended
to be discussed in theoretical framework and might be of interest for physics
and mechanics students as well as for physics teachers.

</DOC>
<DOC>
<DOCNO> 68564 </DOCNO>
Radiative symmetry breaking and Higgs mass bound in the NMSSM


  We study the upper mass bound of the lightest neutral Higgs scalar in the
NMSSM using the RGE analysis. We require the successful occurence of the
electroweak radiative symmetry breaking to restrict the parameter space. As a
result the upper mass bound $m_{h^0}$ is largely restricted compared with the
one estimated without imposing this condition. We point out some features of
$m_{h^0}$ related to the initial value of $h_t$ and discuss why the models with
more extra matters ${\bf 5}+\bar{\bf 5}$ of SU(5) could bring the larger
maximum value of $m_{h^0}$.

</DOC>
<DOC>
<DOCNO> 8334 </DOCNO>
Hysteresis effect due to the exchange Coulomb interaction in


  We calculate the ground-state of a two-dimensional electron gas in a
short-period lateral potential in magnetic field, with the Coulomb
electron-electron interaction included in the Hartree-Fock approximation. For a
sufficiently short period the dominant Coulomb effects are determined by the
exchange interaction. We find numerical solutions of the self-consistent
equations that have hysteresis properties when the magnetic field is tilted and
increased, such that the perpendicular component is always constant. This
behavior is a result of the interplay of the exchange interaction with the
energy dispersion and the spin splitting. We suggest that hysteresis effects of
this type could be observable in magneto-transport and magnetization
experiments on quantum-wire and quantum-dot superlattices.

</DOC>
<DOC>
<DOCNO> 12355 </DOCNO>
The specific heat and optical birefringence of Fe(0.25)Zn(0.75)F2


  The specific heat (Cm) and optical birefringence (\Delta n) for the magnetic
percolation threshold system Fe(0.25)Zn(0.75)F2 are analyzed with the aid of
Monte Carlo (MC) simulations. Both \Delta n and the magnetic energy (Um) are
governed by a linear combination of near-neighbor spin-spin correlations, which
we have determined for \Delta n using MC simulations modeled closely after the
real system. Near a phase transition or when only one interaction dominates,
the temperature derivative of the birefringence [{d(\Delta n)}/{dT}] is
expected to be proportional Cm since all relevant correlations necessarily have
the same temperature dependence. Such a proportionality does not hold for
Fe(0.25)Zn(0.75)F2 at low temperatures, however, indicating that neither
condition above holds. MC results for this percolation system demonstrate that
the shape of the temperature derivative of correlations associated with the
frustrating third-nearest-neighbor interaction differs from that of the
dominant second-nearest-neighbor interaction, accurately explaining the
experimentally observed behavior quantitatively.

</DOC>
<DOC>
<DOCNO> 150336 </DOCNO>
Tachyon condensation and Boundary States in Bosonic String


  We discuss tachyon configuration for the unoriented bosonic string theory
which produces a bosonic string theory with SO(32) gauge symmetry in ten
dimensions. It is closely related to the tachyon condensation scenario proposed
by A. Sen. We also give the boundary state description of the tachyon
condensation process, with some emphasis on the r\^ole of orbifold conformal
field theory.

</DOC>
<DOC>
<DOCNO> 122903 </DOCNO>
Evolution of Cluster Early-Type Galaxies


  The slow evolution of the M/L ratios, colors, and line strengths of cluster
early-type galaxies to z=1 suggests that their stars were formed at very high
redshift. At the same time, morphological studies of distant clusters indicate
significant evolution in the early-type galaxy population. Striking evidence
for strong morphological evolution in clusters is the discovery of a large
number of red merger systems in the cluster MS 1054-03 at z=0.83. The presence
of these mergers is qualitatively consistent with predictions from hierarchical
galaxy formation models, and is direct evidence against an early collapse for
all early-type galaxies. In most of the mergers there is no evidence for strong
star formation. Therefore the mean stellar ages of the merger products will be
much older than the ``assembly age'', and do not violate the constraints on the
star formation epoch of early-type galaxies imposed by the color-magnitude
relation and the Fundamental Plane.

</DOC>
<DOC>
<DOCNO> 99364 </DOCNO>
Random unitaries in non-commutative tori, and an asymptotic model for


  We consider the concept of a q-circular system, which is a deformation of the
circular system from free probability, taking place in the framework of the
so-called 'q-commutation relations'. We show that certain averages of random
unitaries in non-commutative tori behave asymptotically like a q-circular
system.

</DOC>
<DOC>
<DOCNO> 13961 </DOCNO>
Correlation effects in a simple small-world network


  We analyze correlation effects in a simple model of small world networks,
first introduced in \cite{dm}, which is a ring of $N$ sites connected randomly
to a distinguished site at the center. Any two sites connected in this way are
interpreted to be connected by a shortcut. We enter correlations into this
model by taking these random connections from an Ising distribution on the
ring. We will show that correlations tend to decrease the small world effect.

</DOC>
<DOC>
<DOCNO> 12942 </DOCNO>
Variational study of the extended Hubbard-Holstein model on clusters of


  We study the complete extended Hubbard-Holstein Hamiltonian on a four-site
chain with equally spaced sites, with spacing-dependent electronic interaction
parameters evaluated in terms of Wannier functions built from Gaussian atomic
orbitals. By successive application of generalized displacement and squeezing
transformations, an effective polaronic Hamiltonian is obtained, containing a
purely phonon-induced, long-range intersite charge interaction. The phase
diagrams for N=1,2,3,4 electrons have been determined by variational
minimization of the sum of the electronic and the phononic energy, paying
special attention to the effects of the above mentioned phonon-induced
long-range interaction. To characterize the physics of each ground state, we
have evaluated how variations of the site spacing affect the behavior of
several correlation functions of experimental interest, with the aim of
representing lattice deformation effects, either spontaneous or induced by
external pressure.

</DOC>
<DOC>
<DOCNO> 121946 </DOCNO>
The Amount of Dark Matter in Spiral Galaxies


  The `maximum' disk hypothesis of galactic disks imbedded in dark matter halos
is examined. First, decompositions of the rotation curves of NGC 2613, 3198,
6503, and 7184 are analyzed. For these galaxies the radial velocity dispersions
of the stars have been measured. If the parameters of the decompositions are
chosen according to the `maximum' disk hypothesis, the Toomre Q stability
parameter is sytematically less than one, which is a strong argument against
the `maximum' disk hypothesis. Next, density wave theory arguments are used to
describe the morphology of the spiral arms of NGC 3223, 157, and 7083. It is
shown that the `maximum' disk hypothesis is not consistent with the observed
morphologies of the galaxies.

</DOC>
<DOC>
<DOCNO> 121144 </DOCNO>
Warm Absorbing Gas in Cooling Flows


  We summarize the discovery of oxygen absorption and warm (10^5-10^6 K) gas in
cooling flows. Special attention is given to new results for M87 for which we
find the strongest evidence to date for ionized oxygen absorption in these
systems. We briefly discuss implications for observations of cooling flows with
Chandra and XMM.

</DOC>
<DOC>
<DOCNO> 84404 </DOCNO>
A multi-domain spectral method for scalar and vectorial Poisson


  We present a spectral method for solving elliptic equations which arise in
general relativity, namely three-dimensional scalar Poisson equations, as well
as generalized vectorial Poisson equations of the type $\Delta \vec{N} +
\lambda \vec{\nabla}(\vec{\nabla}\cdot \vec{N}) = \vec{S}$ with $\lambda \not=
-1$. The source can extend in all the Euclidean space ${\bf R}^3$, provided it
decays at least as $r^{-3}$. A multi-domain approach is used, along with
spherical coordinates $(r,\theta,\phi)$. In each domain, Chebyshev polynomials
(in $r$ or $1/r$) and spherical harmonics (in $\theta$ and $\phi$) expansions
are used. If the source decays as $r^{-k}$ the error of the numerical solution
is shown to decrease at least as $N^{-2(k-2)}$, where $N$ is the number of
Chebyshev coefficients. The error is even evanescent, i.e. decreases as
$\exp(-N)$, if the source does not contain any spherical harmonics of index
$l\geq k -3$ (scalar case) or $l\geq k-5$ (vectorial case).

</DOC>
<DOC>
<DOCNO> 117309 </DOCNO>
Did 20th century physics have the means to reveal the nature of inertia


  At the beginning of the 20th century the classical electron theory (or,
perhaps more appropriately, the classical electromagnetic mass theory) - the
first physical theory that dared ask the question of what inertia and mass were
- was gaining momentum and there were hopes that physics would be finally able
to explain their origin. It is argued in this paper that if that promising
research path had not been inexplicably abandoned after the advent of
relativity and quantum mechanics, the contemporary physics would have revealed
not only the nature of inertia, mass, and gravitation, but most importantly
would have outlined the ways of their manipulation. Another goal of the paper
is to try to stimulate the search for the mechanism responsible for inertia and
gravitation by outlining a research direction, which demonstrates that the
classical electromagnetic mass theory in conjunction with the principle of
equivalence offers such a mechanism.

</DOC>
<DOC>
<DOCNO> 8926 </DOCNO>
Compositional Inversion Symmetry Breaking in Ferroelectric Perovskites


  Ternary cubic perovskite compounds of the form A_(1/3)A'_(1/3)A''_(1/3)BO_3
and AB_(1/3)B'_(1/3)B''_(1/3)O_3, in which the differentiated cations form an
alternating series of monolayers, are studied using first-principles methods.
Such compounds are representative of a possible new class of materials in which
ferroelectricity is perturbed by compositional breaking of inversion symmetry.
For isovalent substitution on either sublattice, the ferroelectric double-well
potential is found to persist, but becomes sufficiently asymmetric that
minority domains may no longer survive. The strength of the symmetry breaking
is enormously stronger for heterovalent substitution, so that the double-well
behavior is completely destroyed. Possible means of tuning between these
behaviors may allow for the optimization of resulting materials properties.

</DOC>
<DOC>
<DOCNO> 117437 </DOCNO>
The APM Survey for Cool Carbon Stars in the Galactic Halo - II The


  We present proper motion measurements for carbon stars found during the APM
Survey for Cool Carbon Stars in the Galactic Halo (Totten & Irwin, 1998).
Measurements are obtained using a combination of POSSI, POSSII and UKST survey
plates supplemented where necessary by CCD frames taken at the Isaac Newton
Telescope. We find no significant proper motion for any of the new APM
colour-selected carbon stars and so conclude that there are no dwarf carbon
stars present within this sample. We also present proper motion measurements
for three previously known dwarf carbon stars and demonstrate that these
measurements agree favourably with those previously quoted in the literature,
verifying our method of determining proper motions. Results from a
complimentary program of JHK photometry obtained at the South African
Astronomical Observatory are also presented. Dwarf carbon stars are believed to
have anomalous near-infrared colours, and this feature is used for further
investigation of the nature of the APM carbon stars. Our results support the
use of JHK photomtery as a dwarf/giant discriminator and also reinforce the
conclusion that none of the new APM-selected carbon stars are dwarfs. Finally,
proper motion measurements combined with extant JHK photometry are presented
for a sample of previously known Halo carbon stars, suggesting that one of
these stars, CLS29, is likely to be a previously unrecognised dwarf carbon
star.

</DOC>
<DOC>
<DOCNO> 118009 </DOCNO>
Optically dim counterparts of hard X-ray selected AGNs


  We present near-IR photometry and imaging observations of a small sample of
sources identified in the BeppoSAX 5-10 keV survey (HELLAS) which resolves ~
20-30% of the X-ray background at these energies. The near-IR data are combined
with optical spectra and photometry. Only 40% of the sources in our sample have
the blue, power law continuum typical of color-selected QSOs. The remaining 60%
are dominated by a galactic component which, on the basis of the continuum
colors and shape, have ages ranging from 10^9 to 10^10 years. The images show
that the blue QSOs are pointlike at our angular resolution, while all the other
sources are extended, consistent with their spectral appearance and low
redshift. Since down to R=20 only about two thirds of the HELLAS sources have a
counterpart, the preliminary HELLAS census comprises in roughly equal parts: i)
blue QSOs (mostly at high redshifts); ii) optically dim, galaxy-dominated
active nuclei (mostly at modest redshifts); and iii) empty fields (possibly
highly absorbed QSOs at high redshifts).

</DOC>
<DOC>
<DOCNO> 10460 </DOCNO>
Possible f-wave superconductivity in Sr$_2$RuO$_4$?


  Until recently it has been believed that the superconductivity in
Sr$_2$RuO$_4$ is described by p-wave pairing. However, both the recent specific
heat and the magnetic penetration depth measurements on the purest single
crystals of Sr$_2$RuO$_4$ appear to be explained more consistently in terms of
f-wave superconductivity. In order to further this hypothesis, we study
theoretically the thermodynamics and thermal conductivity of f-wave
superconductors in a planar magnetic field. We find the simple expressions for
these quantities when $H \ll H_{c2} $ and $T \ll T_{c}$, which should be
readily accessible experimentally.

</DOC>
<DOC>
<DOCNO> 11029 </DOCNO>
Wannier-function description of the electronic polarization and infrared


  We have constructed maximally-localized Wannier functions for prototype
structures of solid molecular hydrogen under pressure, starting from LDA and
tight-binding Bloch wave functions. Each occupied Wannier function can be
associated with two paired protons, defining a ``Wannier molecule''. The sum of
the dipole moments of these ``molecules'' always gives the correct macroscopic
polarization, even under strong compression, when the overlap between nearby
Wannier functions becomes significant. We find that at megabar pressures the
contributions to the dipoles arising from the overlapping tails of the Wannier
functions is very large. The strong vibron infrared absorption experimentally
observed in phase III, above ~ 150 GPa, is analyzed in terms of the
vibron-induced fluctuations of the Wannier dipoles. We decompose these
fluctuations into ``static'' and ``dynamical'' contributions, and find that at
such high densities the latter term, which increases much more steeply with
pressure, is dominant.

</DOC>
<DOC>
<DOCNO> 40477 </DOCNO>
HERWIG 6: an event generator for Hadron Emission Reactions With


  HERWIG is a general-purpose Monte Carlo event generator, which includes the
simulation of hard lepton-lepton, lepton-hadron and hadron-hadron scattering
and soft hadron-hadron collisions in one package. It uses the parton-shower
approach for initial- and final-state QCD radiation, including colour coherence
effects and azimuthal correlations both within and between jets. This article
updates the description of HERWIG published in 1992, emphasising the new
features incorporated since then. These include, in particular, the matching of
first-order matrix elements with parton showers, a more correct treatment of
heavy quark decays, and a wide range of new processes, including many predicted
by the Minimal Supersymmetric Standard Model, with the option of R-parity
violation. At the same time we offer a brief review of the physics underlying
HERWIG together with details of the input and control parameters and the output
data, to provide a self-contained guide for prospective users of the program.

</DOC>
<DOC>
<DOCNO> 101350 </DOCNO>
Some remarks on A_1^{(1)} soliton cellular automata


  In this short note, we describe the A_1^{(1)} soliton cellular automata as an
evolution of a poset. This allows us to explain the conservation laws for the
A_1^{(1)} soliton cellular automata, one given by Torii, Takahashi and Satsuma,
and the other given by Fukuda, Okado and Yamada, in terms of the stack
permutations of states in a very natural manner. As a biproduct, we can prove a
conjectured formula relating these laws.

</DOC>
<DOC>
<DOCNO> 80927 </DOCNO>
Non-perturbative 3d Lorentzian Quantum Gravity


  We have recently introduced a discrete model of Lorentzian quantum gravity,
given as a regularized non-perturbative state sum over simplicial Lorentzian
space-times, each possessing a unique Wick rotation to Euclidean signature. We
investigate here the phase structure of the Wick-rotated path integral in three
dimensions with the aid of computer simulations. After fine-tuning the
cosmological constant to its critical value, we find a whole range of the
gravitational coupling constant $k_0$ for which the functional integral is
dominated by non-degenerate three-dimensional space-times. We therefore have a
situation in which a well-defined ground state of extended geometry is
generated dynamically from a non-perturbative state sum of fluctuating
geometries. Remarkably, its macroscopic scaling properties resemble those of a
semi-classical spherical universe. Measurements so far indicate that $k_0$
defines an overall scale in this extended phase, without affecting the physics
of the continuum limit. These findings provide further evidence that discrete
{\it Lorentzian} gravity is a promising candidate for a non-trivial theory of
quantum gravity.

</DOC>
<DOC>
<DOCNO> 102166 </DOCNO>
Chains of twists for symplectic Lie algebras


  Serious difficulties arise in the construction of chains of twists for
symplectic Lie algebras. Applying the canonical chains of extended twists to
deform the Hopf algebras U(sp(N)) one is forced to deal only with improper
chains (induced by the U(sl(N)) subalgebras). In the present paper this problem
is solved. For chains of regular injections the sets of maximal extended
jordanian twists F_{E,k} are considered. We prove that there exists for
U(sp(N)) the twist F_{B,k} composed of the factors F_{E,k}. It is demonstrated
that the twisting procedure deforms the space of the primitive subalgebra
sp(N-1). The recursive algorithm for such deformation is found. This
construction generalizes the results obtained for orthogonal classical Lie
algebras and demonstrates the universality of primitivization effect for
regular chains of subalgebras. For the chain of maximal length the twists
F_{B,k,max} become full, their carriers contain the Borel subalgebra B(sp(N)).
Using such twisting procedures one can obtain the explicit quantizations for a
wide class of classical r-matrices. As an example the full chain of extended
twists for U(sp(3)) is considered.

</DOC>
<DOC>
<DOCNO> 12089 </DOCNO>
Non-Fermi Liquid Aspects of Cold and Dense QED and QCD: Equilibrium and


  Infrared divergences from the exchange of dynamically screened magnetic
gluons (photons) lead to the breakdown of the Fermi liquid description of the
{\em normal} state of cold and dense QCD and QED. We implement a resummation of
these divergences via the renormalization group to obtain the spectral density,
dispersion relation, widths and wave function renormalization of single
quasiparticles near the Fermi surface. We find that all feature scaling with
anomalous dimensions:
  $\omega_p({k}) \propto |k-k_F|^{\frac{1}{1-2\lambda}} ~ ; ~ \Gamma(k) \propto
|k-k_F|^{\frac{1}{1-2\lambda}} ~;~ Z_p({k}) \propto
|k-k_F|^{\frac{2\lambda}{1-2\lambda}}$ with $\lambda = \frac{\alpha}{6\pi} ~
{for QED} \vspace{0.5 ex} ~,~ \frac{\alpha_s}{6\pi} \frac{N^2_c-1}{2N_c}
\~~{for QCD with}$. The discontinuity of the distribution function for
quasiparticles near the Fermi surface vanishes. The dynamical renormalization
group is implemented to study the relaxation of quasiparticles in real time.
Quasiparticles with Fermi momentum have vanishing group velocity and relax with
a power law with a coupling dependent anomalous dimension.

</DOC>
<DOC>
<DOCNO> 122782 </DOCNO>
Dissolving star cluster candidates


  We present a list of 34 neglected entries from star cluster catalogues
located at relatively high galactic latitudes ($|b| >$ 15$^{\circ}$) which
appear to be candidate late stages of star cluster dynamical evolution.
Although underpopulated with respect to usual open clusters, they still present
a high number density contrast as compared to the galactic field. This was
verified by means of (i) predicted model counts from different galactic
subsystems in the same direction, and (ii) Guide Star Catalog equal solid angle
counts for the object and surrounding fields. This suggests that the objects
are physical systems, possibly star clusters in the process of disruption or
their fossil remains. The sample will be useful for followup studies in view of
verifying their physi cal nature.

</DOC>
<DOC>
<DOCNO> 101509 </DOCNO>
On the Cohomology of Central Frattini Extensions


  We use topological methods to compute the mod p cohomology of certain
p-groups. More precisely we look at central Frattini extensions of elementary
abelian by elementary abelian groups such that their defining k-invariants span
the entire image of the Bockstein. We show that if p is sufficiently large,
then the mod p cohomology of the extension can be explicitly computed as an
algebra.

</DOC>
<DOC>
<DOCNO> 170615 </DOCNO>
Quantum key distribution via quantum encryption


  A quantum key distribution protocol based on quantum encryption is presented
in this Brief Report. In this protocol, the previously shared
Einstein-Podolsky-Rosen pairs act as the quantum key to encode and decode the
classical cryptography key. The quantum key is reusable and the eavesdropper
cannot elicit any information from the particle Alice sends to Bob. The concept
of quantum encryption is also discussed.

</DOC>
<DOC>
<DOCNO> 9654 </DOCNO>
Magneto-optical control of bright atomic solitons


  In previous work we showed that bright atomic solitons can arise in spinor
Bose-Einstein condensates in the form of gap solitons even for repulsive
many-body interactions. Here we further explore the properties of atomic gap
solitons and show that their internal structure can be used to both excite them
and control their center-of-mass motion using applied laser and magnetic
fields. As an illustration we demonstrate a nonlinear atom-optical Mach-Zehnder
interferometer based on gap solitons.

</DOC>
<DOC>
<DOCNO> 100108 </DOCNO>
Proof of a Symmetrized Trace Conjecture for the Abelian Born-Infeld


  In this paper we prove a conjecture regarding the form of the Born-Infeld
Lagrangian with a U(1)^2n gauge group after the elimination of the auxiliary
fields. We show that the Lagrangian can be written as a symmetrized trace of
Lorentz invariant bilinears in the field strength. More generally we prove a
theorem regarding certain solutions of unilateral matrix equations of arbitrary
order. For solutions which have perturbative expansions in the matrix
coefficients, the solution and all its positive powers are sums of terms which
are symmetrized in all the matrix coefficients and of terms which are
commutators.

</DOC>
<DOC>
<DOCNO> 9402 </DOCNO>
Screened electrostatic interactions between clay platelets


  An effective pair potential for systems of uniformly charged lamellar
colloids in the presence of an electrolytic solution of microscopic co- and
counterions is derived. The charge distribution on the discs is expressed as a
collection of multipole moments, and the tensors which determine the
interactions between these multipoles are derived from a screened Coulomb
potential. Unlike previous studies of such systems, the interaction energy may
now be expressed for discs at arbitrary mutual orientation. The potential is
shown to be exactly equivalent to the use of linearized Poisson-Boltzmann
theory.

</DOC>
<DOC>
<DOCNO> 120088 </DOCNO>
Eigenvalues of the Stewart-Lyth equation for inflation with a blue


  By using the rather stringent nonlinear second order slow-roll approximation,
we reconsider the nonlinear second order Abel equation of Stewart and Lyth. We
determine a new blue eigenvalue spectrum. Some of the discrete values of the
spectral index $n_s$ have consistent fits to the cumulative COBE data as well
as to recent ground-base CMB experiments.

</DOC>
<DOC>
<DOCNO> 71655 </DOCNO>
Logarithmically rising hh and $\gamma h$ cross-sections: some features


  A Regge model of the Pomeron with intercept equal to one, leading to rising
cross-sections is considered. Analysis of the experimental data on hadron and
photon induced interactions is performed within the model. It is shown that the
available pure hadronic data as well as data on DIS are compatible with a high
energy logarithmic behaviour of cross-sections and do not require a Pomeron
intercept above one. The very important r\^ole of the preasymptotic
contributions is especially emphasized.

</DOC>
<DOC>
<DOCNO> 10749 </DOCNO>
Coherence and Partial Coherence in Interacting Electron Systems


  We study coherence of electron transport through interacting quantum dots and
discuss the relation of the coherent part to the flux-sensitive conductance for
three different types of Aharonov-Bohm interferometers. Contributions to
transport in first and second order in the intrinsic line width of the dot
levels are addressed in detail. We predict an asymmetry of the interference
signal around resonance peaks as a consequence of incoherence associated with
spin-flip processes. Furthermore, we show by strict calculation that
first-order contributions can be partially or even fully coherent. This
contrasts with the sequential-tunneling picture which describes first-order
transport as a sequence of incoherent tunneling processes.

</DOC>
<DOC>
<DOCNO> 117701 </DOCNO>
External Shock Model for Gamma-Ray Bursts during the Prompt Phase


  The hard X-ray and gamma-ray phenomenology of gamma-ray bursts (GRBs) can be
explained by an external shock model where a single relativistic blast wave
interacts with the surrounding medium. Besides reproducing the generic spectral
behavior of GRB profiles, the external shock model provides quantitative fits
to the peak flux distribution, the > 1 s t_{50} duration distribution, and the
distribution of the peaks E_pk of the vF_v spectra of GRBs measured with BATSE.
The apparent paradox between a relativistic beaming scenario and the empirical
finding that E_pk values are preferentially measured within the triggering
range of a GRB detector is resolved by this model when blast wave physics and
detector triggering criteria are taken into account. Some surprising
implications follow, namely that the fireball event rate is ~1 per 10^4 years
per Milky Way galaxy for unbeamed sources, and proportionally more if fireball
outflows are collimated. This is ~ 3 orders of magnitude larger than normally
quoted. Most of the clean and dirty fireball transients are undetected due to
telescope sensitivity and design limitations.
  Strongly variable GRB time histories with good radiative efficiencies are
possible because of the strongly enhanced emissions when a blast wave interacts
with density inhomogeneities located nearly along the line-of-sight to the
observer. Arguments against short timescale variability in an external shock
model are answered, and difficulties in an internal shock/colliding shell model
are mentioned.

</DOC>
<DOC>
<DOCNO> 100491 </DOCNO>
Cotangent and tangent modules on quantum orbits


  Let $k(S^2_q)$ be the "coordinate ring" of a quantum sphere. We introduce the
cotangent module on the quantum sphere as a one-sided $k(S^2_q)$-module and
show that there is no Yang-Baxter type operator converting it into a
$k(S^2_q)$-bimodule which would be a flatly deformed object w.r.t. its
classical counterpart. This implies non-flatness of any covariant differential
calculus on the quantum sphere making use of the Leibniz rule. Also, we
introduce the cotangent and tangent modules on generic quantum orbits and
discuss some related problems of "braided geometry".

</DOC>
<DOC>
<DOCNO> 70241 </DOCNO>
Electromagnetic radiation from superconducting string cusps


  Cusps in superconducting cosmic strings produce strongly beamed
electromagnetic radiation. To calculate the energy emitted requires taking into
account the effect of the charge carriers on the string motion, which has
previously been done only heuristically. Here, we use the known exact solution
to the equations of motion for the case where the current is chiral to update
previous calculations for the total energy, spectrum and angular distribution
in that case. We analyze the dependence of the radiated energy on the cusp
parameters, and discuss which types of cusp dominate the total radiation
emitted from an ensemble.

</DOC>
<DOC>
<DOCNO> 150568 </DOCNO>
A Note on Superfields and Noncommutative Geometry


  We consider the supersymmetric field theories on the noncommutative $R^4$
using the superspace formalism on the commutative space. The terms depending on
the parameter of the noncommutativity $\Theta$ are regarded as the
interactions. In this way we construct the N=1 supersymmetric action for the
U(N) vector multiplets and chiral multiplets of the fundamental,
anti-fundamental and adjoint representations of the gauge group. The action for
vector multiplets of the products gauge group and its bi-fundamental matters is
also obtained. We discuss the problem of the derivative terms of the auxiliary
fields.

</DOC>
<DOC>
<DOCNO> 150610 </DOCNO>
Domain Wall Junctions in Supersymmetric Field Theories in D=4


  We study the possible BPS domain wall junction configurations for general
polynomial superpotentials of N=1 supersymmetric Wess-Zumino models in D=4. We
scan the parameter space of the superpotential and find different possible BPS
states for different values of the deformation parameters and present our
results graphically. We comment on the domain walls in F/M/IIA theories
obtained from the Calabi-Yau fourfolds with isolated singularities and a
background flux.

</DOC>
<DOC>
<DOCNO> 68738 </DOCNO>
Spontaneous Scale Symmetry Breaking in 2+1-Dimensional QED at Both Zero


  A complete analysis of dynamical scale symmetry breaking in 2+1-dimensional
QED at both zero and finite temperature is presented by looking at solutions to
the Schwinger-Dyson equation. In different kinetic energy regimes we use
various numerical and analytic techniques (including an expansion in large
flavour number). It is confirmed that, contrary to the case of 3+1 dimensions,
there is no dynamical scale symmetry breaking at zero temperature, despite the
fact that chiral symmetry breaking can occur dynamically. At finite
temperature, such breaking of scale symmetry may take place.

</DOC>
<DOC>
<DOCNO> 13792 </DOCNO>
Fluctuations in $YBa_{2}Cu_{3}O_{6.5}$ single crystal: an evidence for


  Magnetization measurements as a function of temperature are reported for
$YBa_{2}Cu_{3}O_{6.5}$ crystal (T_{c}=45.2 K) for fields between 0.2 to $3.5\
Tesla$. All isochamps for H>1 Tesla intersect at $T_{2D}^{\star}\simeq 42.8\
K$, implying fluctuations contribution to the magnetization. These curves
collapse into a single curve when magnetization and temperature are scaled
according to the predicted ''2D scaling'' in the fluctuation regime.
Surprisingly, the low field curves also intersect, at $T_{3D}^{\star}\simeq
43.4 K$, and they obey a 3D scaling. We provide a theoretical picture of the
magnetization in the fluctuation regime based on the Lawrence-Doniach model.
Within this model we calculate the field and temperature dependence of the
magnetization. The two intersection points and the $2D\to 3D$ crossover are
consistent with the experimental observation.

</DOC>
<DOC>
<DOCNO> 9877 </DOCNO>
New derivation of the cluster cumulant formula


  The cluster cumulant formula of Kubo is derived by appealing only to
elementary properties of subsets and binomial coefficients. It is shown to be a
binomial transform of the grand potential. Extensivity is proven without
introducing cumulants. A combinatorial inversion is used to reformulate the
expansion in the activity to one in occupation probabilities, which explicitly
control the convergence. The classical virial expansion is recovered to third
order as an example.

</DOC>
<DOC>
<DOCNO> 179035 </DOCNO>
The role of Delta(1700) excitation and rho production in double pion


  Recent information on invariant mass distributions of the $\gamma
p\to\pi^+\pi^0 n$ reaction, where previous theoretical models had shown
deficiencies, have made more evident the need for new mechanisms, so far
neglected or inaccurately included. We have updated a previous model to include
new necessary mechanisms. We find that the production of the $\rho$ meson, and
the $\Delta(1700)$ excitation, through interference with the dominant terms,
are important mechanisms that solve the puzzle of the $\gamma p\to\pi^+\pi^0 n$
reaction without spoiling the early agreement with the $\gamma p\to\pi^+\pi^-
p$ and $\gamma p\to\pi^0\pi^0 p$ reactions.

</DOC>
<DOC>
<DOCNO> 100617 </DOCNO>
Algebraic Surfaces Holomorphically Dominable by C2


  An n-dimensional complex manifold M is said to be (holomorphically) 
dominable by $\CC^n$ if there is a map $F:\CC^n \ra M$ which is holomorphic
such that the Jacobian determinant $\det(DF)$ is not identically zero. Such a
map F is called a dominating map. In this paper, we attempt to classify
algebraic surfaces X which are dominable by $\CC^2$ using a combination of
techniques from algebraic topology, complex geometry and analysis. One of the
key tools in the study of algebraic surfaces is the notion of Kodaira dimension
(defined in section 2). By Kodaira's pioneering work and its extensions, an
algebraic surface which is dominable by $\CC^2$ must have Kodaira dimension
less than two. Using the Kodaira dimension and the fundamental group of X, we
succeed in classifying algebraic surfaces which are dominable by $\CC^2$ except
for certain cases in which X is an algebraic surface of Kodaira dimension zero
and the case when X is rational without any logarithmic 1-form. More
specifically, in the case when X is compact (namely projective), we need to
exclude only the case when X is birationally equivalent to a K3 surface (a
simply connected compact complex surface which admits a globally non-vanishing
holomorphic 2-form) that is neither elliptic nor Kummer (see sections 3 and 4
for the definition of these types of surfaces).

</DOC>
<DOC>
<DOCNO> 150396 </DOCNO>
Actions for Curved Branes


  The nondeterminantal forms of the Born-Infeld and related brane actions in
which the gauge fields couple to both an induced metric and an intrinsic metric
are generalised by letting either or both metrics be dynamical. The resulting
actions describe ` brane world' and cosmological scenarios in which the gauge
fields are confined to the brane, while gravity propagates in both the
world-volume and the bulk. In particular, for actions involving a nonsymmetric
` metric', nonsymmetric gravity propagates on the worldvolume. For 3-branes
with a symmetric metric, conformal (Weyl) gravity propagates on the worldvolume
and has conformally invariant couplings to the gauge fields.

</DOC>
<DOC>
<DOCNO> 68872 </DOCNO>
Heavy Quark Impact Factor at Next-to-leading Level


  We further analyze the definition and the calculation of the heavy quark
impact factor at next-to-leading (NL) log(s) level, and we provide its
analytical expression in a previously proposed k-factorization scheme. Our
results indicate that k-factorization holds at NL level with a properly chosen
energy scale, and with the same gluonic Green's function previously found in
the massless probe case.

</DOC>
<DOC>
<DOCNO> 12983 </DOCNO>
Phonons and Solitons in 1D Mott Insulators


  We study the problem of one-dimensional (1D) Luttinger liquids in the
insulating Mott-Hubbard phase in the presence of acoustic phonons in the
semiclassical limit. We show that solitonic excitations can propagate freely in
the system and the energy required to produce a soliton is reduced by a
polaronic effect. We find a critical value of the electron-phonon coupling
constant for which this energy vanishes.

</DOC>
<DOC>
<DOCNO> 71022 </DOCNO>
Violation of the Feynman scaling law as a manifestation of


  We demonstrate that the apparently ad hoc parametrization of the particle
production spectra discussed in the literature and used in description of
cosmic ray data can be derived from the information theory approach to
multiparticle production processes. In particular, the violation of the Feynman
scaling law can be interpreted as a manifestation of nonextensivity of the
production processes.

</DOC>
<DOC>
<DOCNO> 84965 </DOCNO>
Dynamical Properties of Euclidean Solutions in a Multidimensional


  In the framework of the Hartle-Hawking no-boundary proposal, we investigated
quantum creation of the multidimensional universe with a cosmological constant
($\Lambda$) but without matter fields. We have found that the classical
solutions of the Euclidean Einstein equations in this model have
``quasi-attractors'', i.e., most trajectories on the a-b plane, where a and b
are the scale factors of external and internal spaces, go around a point. It is
presumed that the wave function of the universe has a hump near this
quasi-attractor point. In the case that both the curvatures of external and
internal spaces are positive, and $\Lambda>0$, there exist Lorentzian solutions
which start near the quasi-attractor, the internal space remains microscopic,
and the external space evolves into our macroscopic universe.

</DOC>
<DOC>
<DOCNO> 67798 </DOCNO>
Models of Neutrino Mass and Mixing


  There are two basic theoretical approaches to obtaining neutrino mass and
mixing. In the minimalist approach, one adds just enough new stuff to the
Minimal Standard Model to get $m_\nu \neq 0$ and $U_{\alpha i} \neq 1$. In the
holistic approach, one uses a general framework or principle to enlarge the
Minimal Standard Model such that, among other things, $m_\nu \neq 0$ and
$U_{\alpha i} \neq 1$. In both cases, there are important side effects besides
neutrino oscillations. I discuss a number of examples, including the
possibility of leptogenesis from R parity nonconservation in supersymmetry.

</DOC>
<DOC>
<DOCNO> 119083 </DOCNO>
Imaging of the protoelliptical NGC 1700 and its globular cluster system


  An excellent candidate for a young elliptical, or `protoelliptical' galaxy is
NGC 1700. Here we present new B, V and I band imaging using the Keck telescope
and reanalyse existing V and I band images from the Hubble Space Telescope.
After subtracting a model of the galaxy from the Keck images NGC 1700 reveals
two symmetric tidal tail-like structures. If this interpretation is correct, it
suggests a past merger event involving two spiral galaxies. These tails are
largely responsible for the `boxiness' of the galaxy isophotes observed at a
radius of about 13 kpc. We also show that the B-I colour distribution of the
globular cluster system is bimodal. The mean colour of the blue population is
consistent with those of old Galactic globular clusters. Relative to this old,
metal poor population, we find that the red population is younger and more
metal rich. This young population has a similar age and metallicity as that
inferred for the central stars, suggesting that they are both associated with
an episode of star formation triggered by the merger that may have formed the
galaxy. Although possessing large errors, we find that the majority of the age
estimates of NGC 1700 are reasonably consistent and we adopt a `best estimate'
for the age of 3.0 +/-1.0 Gyr. This relatively young age places NGC 1700 within
the age range where there is a notable lack of obvious candidates for
protoellipticals. The total globular cluster specific frequency is rather low
for a typical elliptical, even after taking into account fading of the galaxy
over the next 10 Gyr. We speculate that NGC 1700 will eventually form a
relatively `globular cluster poor' elliptical galaxy.

</DOC>
<DOC>
<DOCNO> 119827 </DOCNO>
First Observations of the Magnetic Field Geometry in Pre-stellar Cores


  We present the first published maps of magnetic fields in pre-stellar cores,
to test theoretical ideas about the way in which the magnetic field geometry
affects the star formation process. The observations are JCMT-SCUBA maps of 850
micron thermal emission from dust. Linear polarizations at typically ten or
more independent positions in each of three objects, L1544, L183 and L43 were
measured, and the geometries of the magnetic fields in the plane of the sky
were mapped from the polarization directions. The observed polarizations in all
three objects appear smooth and fairly uniform. In L1544 and L183 the mean
magnetic fields are at an angle of around 30 degrees to the minor axes of the
cores. The L43 B-field appears to have been influenced in its southern half,
such that it is parallel to the wall of a cavity produced by a CO outflow from
a nearby T Tauri star, whilst in the northern half the field appears less
disturbed and has an angle of 44 degrees to the core minor axis. We briefly
compare our results with published models of magnetized cloud cores and
conclude that no current model can explain these observations simultaneously
with previous ISOCAM data.

</DOC>
<DOC>
<DOCNO> 11265 </DOCNO>
Phase transitions in the one-dimensional spin-S $J_1-J_2$ XY model


  The one-dimensional spin-S $J_1-J_2$ XY model is studied within the
bosonization approach. Around the two limits ($J_2/J_1 \ll 1,J_2/J_1 \gg 1$)
where a field theoretical analysis can be derived, we discuss the phases as
well as the different phase transitions that occur in the model. In particular,
it is found that the chiral critical spin nematic phase, first discovered by
Nersesyan et al. (Phys. Rev. Lett. {\bf 81}, 910 (1998)) for $S=1/2$, exists in
the general spin-S case. The nature of the effective field theory that
describes the transition between this chiral critical phase and a chiral gapped
phase is also determined.

</DOC>
<DOC>
<DOCNO> 121328 </DOCNO>
The Luminosity Function of 80 Abell Clusters from the CRoNaRio


  We present the composite luminosity function (hereafter LF) of galaxies for
80 Abell clusters studied in our survey of the Northern Hemisphere, using DPOSS
data in the framework of the CRoNaRio collaboration. Our determination of the
LF has been computed with very high accuracy thanks to the use of homogeneous
data both for the clusters and the control fields and to a local estimate of
the background, which takes into account the presence of large-scale structures
and of foreground clusters and groups.
  The global composite LF is quite flat down to M^+5 and it has a slope
alpha=-1.0 +/- 0.2 with minor variations from blue to red filters, and M^* =
-21.9,-22.0,-22.3 mag (H_0=50 km s^-1 Mpc^-1) in g, r and i filters,
respectively (errors are detailed in the text).
  We find a significant difference between rich and poor clusters supporting
the existence of an LF's dependence on the environment.

</DOC>
<DOC>
<DOCNO> 151431 </DOCNO>
Extended BRS Symmetry and Gauge Independence in On-Shell Renormalization


  Extended BRS symmetry is used to prove gauge independence of the fermion
renormalization constant $Z_2$ in on-shell QED renormalization schemes. A
necessary condition for gauge independence of $Z_2$ in on-shell QCD
renormalization schemes is formulated. Satisfying this necessary condition
appears to be problematic at the three-loop level in QCD.

</DOC>
<DOC>
<DOCNO> 40204 </DOCNO>
Measurements of charmless three-body and quasi-two-body B decays


  We present preliminary results of a search for several exclusive charmless
hadronic B decays from electron-positron annihilation data collected by the
BABAR detector near the Y(4S) resonance. These include three-body decay modes
with final states h^{+/-}h^{-/+}h^{+/-} and h^{+/-}h^{-/+}pi^0, and
quasi-two-body decay modes with final states X^0 h and X^0 K0S, where h = pi or
K and X^0 = eta^' or omega. We find B(B^0 --> rho^(-/+)pi^(+/-)) =
(49+/-13^{+6}_{-5}) x 10^{-6} and B(B^+ --> eta^' K^+) = (62+/-18+/-8) x
10^{-6} and present upper limits for eight other decays.

</DOC>
<DOC>
<DOCNO> 84083 </DOCNO>
The inverse scattering method for cylindrical gravitational waves


  The initial-value problem for cylindrical gravitational waves is studied
through the development of the inverse scattering method scheme. The inverse
scattering transform in this case can be viewed as a transformation of the
Cauchy data to the data on the symmetry axis. Riemann-Hilbert problem, which
serves as inverse transformation, is formulated in two different ways. We
consider Einstein-Rosen waves to illustrate the method.

</DOC>
<DOC>
<DOCNO> 9351 </DOCNO>
Comment on: Thermal model for Adaptive Competition in a Market


  We show that the dynamical equations describing the collective behavior of
the model introduced by Cavagna et al. i) are not their Eqs. (5,6) but rather
ii) are the same as those of the minority game (MG). As a consequence the
analytic solution of the MG presented in [PRL, 84, 1824 (2000)] holds also for
this model. Finally we show that iii) the the large temperature behavior of the
model is different, due to small simulation times, from that discussed by
Cavagna et al.

</DOC>
<DOC>
<DOCNO> 11523 </DOCNO>
Enhancement and suppression of spontaneous emission and light scattering


  Quantum degeneracy modifies light scattering and spontaneous emission. For
fermions, Pauli blocking leads to a suppression of both processes. In contrast,
in a weakly interacting Bose-Einstein condensate, we find spontaneous emission
to be enhanced, while light scattering is suppressed. This difference is
attributed to many-body effects and quantum interference in a Bose-Einstein
condensate.

</DOC>
<DOC>
<DOCNO> 70933 </DOCNO>
Understanding the linear see-saw neutrino mass relations and large


  We study the effective ways for generating the linear see-saw neutrino mass
relations and large neutrino mixing angles in two classes of grand unified
SO(10) models where the texture of Dirac neutrino mass matrix is related to
either the charged lepton mass matrix (case A) or the up-quark mass matrix
(case B). We also briefly analyse their stability criteria and they are found
to be stable under under radiative corrections at low energies.

</DOC>
<DOC>
<DOCNO> 10681 </DOCNO>
Critical points in two-dimensional replica sigma models


  I survey the kinds of critical behavior believed to be exhibited in
two-dimensional disordered systems. I review the different replica sigma models
used to describe the low-energy physics, and discuss how critical points appear
because of WZW and theta terms.

</DOC>
<DOC>
<DOCNO> 178409 </DOCNO>
Freeze-out in hydrodynamical models in relativistic heavy ion collisions


  Freeze-out of particles across 3-dimensional space-time hypersurface with
space-like normal is discussed in a simple kinetic model. The final momentum
distribution of emitted particles shows a non-exponential transverse momentum
spectrum, which is in quantitative agreement with recently measured SPS pion
and $h^-$ spectra.

</DOC>
<DOC>
<DOCNO> 119883 </DOCNO>
Possible Discrimination between Gamma Rays and Hadrons using Cerenkov


  Atmospheric \v{C}erenkov Technique is an established methodology to study
$TeV$ energy gamma rays. However the challenging problem has always been the
poor signal to noise ratio due to the presence of abundant cosmic rays. Several
ingenious techniques have been employed to alleviate this problem, most of
which are centred around the \v{C}erenkov image characteristics. However there
are not many techniques available for improving the signal to noise ratio of
the data from wavefront sampling observations. One such possible technique is
to use the \v{C}erenkov photon arrival times and identify the species dependent
characteristics in them. Here we carry out systematic monte carlo simulation
studies of the timing information of \v{C}erenkov photons at the observation
level. We have parameterized the shape of the \v{C}erenkov shower front as well
as the pulse shapes in terms of experimentally measurable quantities. We
demonstrate the sensitivity of the curvature of the shower front, pulse shape
parameters as well as the photon arrival time jitter to primary species and
show their efficiency in improving the signal to noise ratio. The effect of
limiting the \v{C}erenkov telescope opening angle by using a circular focal
point mask, onthe efficacy of the parameters has also been studied for each of
the parameters. Radius of the shower front, pulse decay time and photon arrival
time jitter have been found to be the most promising parameters which could be
used to discriminate $\gamma -$ray events from the background. We also find
that the efficiency of the first two parameters increases with zenith angle and
efficiency of pulse decay time decreases with increasing altitude of
observation.

</DOC>
<DOC>
<DOCNO> 99481 </DOCNO>
The Phenomenological Preparation - Registration Arrow of Time and its


  The observed probabilities of quantum mechanics possess a time asymmetry
which is based on the truism that a state must be prepared before an observable
can be measured in it. While Hilbert space quantum theory cannot incorporate
this arrow of time, the Rigged Hilbert Space (RHS) formulation of quantum
mechanics provides a theory of time symmetric as well as time asymmetric
quantum physics.

</DOC>
<DOC>
<DOCNO> 121358 </DOCNO>
Excitation of H_2 and HD in shocks and PDRs


  Photodissociation regions (PDRs) and shocks give rise to conspicuous emission
from rotationally and vibrationally excited molecular hydrogen. This line
emission has now been studied with ISO and from the ground in great detail. A
remarkable discovery has been that toward the Orion outflow and other
shock-excited regions, the H_2 level populations show a very high excitation
component. We suggest that these high-excitation populations may arise from
non-thermal pumping processes, such as H_2 formation and high-velocity
ion-molecule collision in partially dissociative shocks. In PDRs such as NGC
7023 however, formation pumping is always less important than fluorescent
pumping. We furthermore present two HD emission line detections toward Orion
Peak 1. This enables the first comparison of the H_2 and the HD excitation,
which surprisingly turn out to be identical.

</DOC>
<DOC>
<DOCNO> 11291 </DOCNO>
Controlling of exciton condensate by external fields and phonon laser


  The novel method of observation and controlling of Bose-Einstein condensation
in the system of spatially and momentum-space indirect excitons in coupled
quantum wells using in-plane magnetic and normal electric fields is proposed.
Fields are used for exciton dispersion engeneering. In the presence of in-plane
magnetic field ground state of spatially indirect exciton becomes also indirect
in the momentum space. Manipulation of electric field magnitude is used for
tuning to resonance of transition of "dark" long-life spatially and
momentum-space indirect exciton in condensate into spatially and momentum-space
direct exciton in radiative zone, with phonon creation, and with subsequent
recombination of the direct exciton in radiative zone. Recombination rate of
indirect excitons in condensate according to proposed scheme sharply rises at
resonance. As a result besides enhanced spectral narrow photoluminescence
connected with recombination of direct exciton in radiative zone with specific
angular dependence, almost monochromatic and unidirectional beam of phonons
appears. An opportunity of obtaining of "phonon laser" radiation on the basis
of this effect in considered.

</DOC>
<DOC>
<DOCNO> 71377 </DOCNO>
Does the weak coupling limit of the Burden-Tjiang deconstruction of the


  We derive constraints on the non-perturbative 3-point fermion-boson
transverse vertex in massless QED3 from its perturbative calculation to order
$\alpha$. We also check the transversality condition to two loops and evaluate
the fermion propagator to the same order. We compare a conjecture of the
non-perturbative vertex by Burden and Tjiang against our results and comment on
its draw backs. Our calculation calls for the need to construct a
non-perturbative form for the fermion-boson vertex which agrees with its
perturbative limit to ${\cal O}(\alpha)$.

</DOC>
<DOC>
<DOCNO> 101764 </DOCNO>
Extendibility, monodromy and local triviality for topological groupoids


  A groupoid is a small category in which each morphism has an inverse. A
topological groupoid is a groupoid in which both sets of objects and morphisms
have topologies such that all groupoid structure maps are continuous. The
notion of monodromy groupoid of a topological groupoid generalises those of
fundamental groupoid and universal covering. It was earlier proved that the
monodromy of a locally sectionable topological groupoid has a topological
groupoid structure satisfying some properties. In this paper a similar problem
is studied for compatible locally trivial topological groupoids.

</DOC>
<DOC>
<DOCNO> 150869 </DOCNO>
Supersymmetry without hermiticity


  A new model of supersymmetry between bosons and fermions is proposed. Its
representation space is spanned by states with PT symmetry and real energies
but the inter-related partner Hamiltonians themselves remain complex and
non-Hermitian. The formalism admits vanishing Witten index.

</DOC>
<DOC>
<DOCNO> 120116 </DOCNO>
ATLAS: a Cassegrain spectrograph based on volume phase holographic


  We are proposing a new spectrograph (ATLAS) which would revolutionise
intermediate-dispersion observations at the AAT. Based on the new technology of
Volume Phase Holographic gratings, and using transmission optics, ATLAS offers
high throughput and a wide field (24'). It will be ideally suited to extensive
surveys of faint objects. It has been designed with a collimated beam diameter
of 150 mm, giving resolution lambda/delta lambda up to nearly 10,000 with a 1.5
arcsecond slit and good efficiency. It will be a dual-beam instrument, to
maximise observing speed and allow optimised optical coatings to be used. The
project is working towards its Concept Design Review which will occur during
2000.

</DOC>
<DOC>
<DOCNO> 68982 </DOCNO>
Collision-Induced Decay of Metastable Baby Skyrmions


  Many extensions of the standard model predict heavy metastable particles
which may be modeled as solitons (skyrmions of the Higgs field), relating their
particle number to a winding number. Previous work has shown that the
electroweak interactions admit processes in which these solitons decay,
violating standard model baryon number. We motivate the hypothesis that
baryon-number-violating decay is a generic outcome of collisions between these
heavy particles. We do so by exploring a 2+1 dimensional theory which also
possesses metastable skyrmions. We use relaxation techniques to determine the
size, shape and energy of static solitons in their ground state. These solitons
could decay by quantum mechanical tunneling. Classically, they are metastable:
only a finite excitation energy is required to induce their decay. We attempt
to induce soliton decay in a classical simulation by colliding pairs of
solitons. We analyze the collision of solitons with varying inherent
stabilities and varying incident velocities and orientations. Our results
suggest that winding-number violating decay is a generic outcome of collisions.
All that is required is sufficient (not necessarily very large) incident
velocity; no fine-tuning of initial conditions is required.

</DOC>
<DOC>
<DOCNO> 70761 </DOCNO>
Parton distribution functions from nonlocal light-cone operators with


  We introduce the chiral-even and chiral-odd quark distributions as forward
matrix elements of related bilocal quark operators with well-defined
(geometric) twist. Thereby, we achieve a Lorentz invariant classification of
these distributions which differ from the conventional ones by explicitly
taking into account the necessary trace terms. The relations between both kinds
of distribution functions are given and the mismatch between their different
definition of twist is discussed. Wandzura-Wilczek--like relations between the
conventional distributions (based on dynamical twist) are derived by means of
geometric twist distribution functions.

</DOC>
<DOC>
<DOCNO> 9289 </DOCNO>
The Semiclassical Propagator for Spin Coherent States


  We use a continuous-time path integral to obtain the semiclassical propagator
for minimal-spread spin coherent states. We pay particular attention to the
``extra phase'' discovered by Solari and Kochetov, and show that this
correction is related to an anomaly in the fluctuation determinant. We show
that, once this extra factor is included, the semiclassical propagator has the
correct short time behaviour to $O(T^2)$, and demonstrate its consistency under
dissection of the path

</DOC>
<DOC>
<DOCNO> 70401 </DOCNO>
How to understand the lightest scalars


  Based on previous papers I discuss how I understand the lightest scalars
using a general coupled channel model. This model includes all light
two-pseudoscalar thresholds, constraints from Adler zeroes, flavour symmetric
couplings, unitarity and physically acceptable analyticity. One finds that with
a large coupling there can appear two physical resonance poles on the second
sheet although only one bare quark-antiquark state is put in. The f0(980) and
f0(1370) resonance poles are thus in this model two manifestations of the same
strange-antistrange quark state. On the other hand, the isoscalar state
containing u and d quarks becomes (when unitarized and strongly distorted by
hadronic mass shifts) a very broad resonance, with its pole at 470-i250 MeV.
This is the sigma meson required by models for spontaneous breaking of chiral
symmetry.

</DOC>
<DOC>
<DOCNO> 83248 </DOCNO>
Constraint compiling into rules formalism constraint compiling into


  In this paper we present a rule based formalism for filtering variables
domains of constraints. This formalism is well adapted for solving dynamic CSP.
We take diagnosis as an instance problem to illustrate the use of these rules.
A diagnosis problem is seen like finding all the minimal sets of constraints to
be relaxed in the constraint network that models the device to be diagnosed

</DOC>
<DOC>
<DOCNO> 13344 </DOCNO>
The Magnetic Spin Ladder (C_{5}H_{12}N)_{2}CuBr_{4}: High Field


  The magnetization, $M(H \leq 30$ T, 0.7 K $\leq T \leq 300$ K), from single
crystals and powder samples of (C$_{5}$H$_{12}$N)$_{2}$CuBr$_{4}$ has been used
to identify this system as an $S=1/2$ Heisenberg two-leg ladder in the strong
coupling limit, $J_{\perp} = 13.3$ K and $J_{\parallel} = 3.8$ K, with $H_{c1}
= 6.6$ T and $H_{c2} = 14.6$ T. An inflection point in $M(H, T = 0.7$ K) at
half-saturation, $M_{s}/2$, is described by an effective \emph{XXZ} chain. The
data exhibit universal scaling behavior in the vicinity of $H_{c1}$ and
$H_{c2}$, indicating the system is near a quantum critical point.

</DOC>
<DOC>
<DOCNO> 12657 </DOCNO>
Ground states versus low-temperature equilibria in random field Ising


  We discuss with the aid of random walk arguments and exact numerical
computations the magnetization properties of one-dimensional random field
chains. The ground state structure is explained in terms of absorbing and
non-absorbing random walk excursions. At low temperatures, the magnetization
profiles follow those of the ground states except at regions where a local
random field fluctuation makes thermal excitations feasible. This follows also
from the non-absorbing random walks, and implies that the magnetization length
scale is a product of these two scales. It is not simply given by the
Imry-Ma-like ground state domain size nor by the scale of the thermal
excitations.

</DOC>
<DOC>
<DOCNO> 151006 </DOCNO>
The Discrete Bound State Spectrum of the Rotating D0-brane System


  In this note we obtain the discrete spectrum of the rotating ellipsoidal
membrane, the solution to classical equations of motion in the matrix mechanics
of N D0-branes. This solution has the interpretation of a closed D2-brane with
the D0-branes bound to its surface. The semi-classical quantization is
performed on the rotational modes with the result that both radii and energy
are quantized. We also argue that the quantum mechanics of this system is well
defined, with a unique ground state of positive energy in each sector with a
non-zero angular momentum. The scaling of the size and energy of these states
allows us to identify our rotating brane excited states with the previously
conjectured resonances in the scattering of D0-branes.

</DOC>
<DOC>
<DOCNO> 69536 </DOCNO>
Nonexistence of the Longitudinal Polarisation of a Massive Gauge Bosons


  This paper has been withdrawn by the authors due to some errors.

</DOC>
<DOC>
<DOCNO> 8296 </DOCNO>
Nonuniversal mound formation in nonequilibrium surface growth


  We demonstrate, using well-established nonequilibrium limited-mobility
solid-on-solid growth models, that mound formation in the dynamical surface
growth morphology does not necessarily imply the existence of a surface edge
diffusion bias (the Schwoebel barrier). We find mounded morphologies in several
nonequilibrium growth models which incorporate no Schwoebel barrier. Our
numerical results indicate that mounded morphologies in nonequilibrium surface
growth may arise from a number of distinct physical mechanisms, with the
Schwoebel instability being one of them.

</DOC>
<DOC>
<DOCNO> 119302 </DOCNO>
Overview of the Far Ultraviolet Spectroscopic Explorer Mission


  The Far Ultraviolet Spectroscopic Explorer satellite observes light in the
far-ultraviolet spectral region, 905 - 1187 A with high spectral resolution.
The instrument consists of four coaligned prime-focus telescopes and Rowland
spectrographs with microchannel plate detectors. Two of the telescope channels
use Al:LiF coatings for optimum reflectivity from approximately 1000 to 1187 A
and the other two use SiC coatings for optimized throughput between 905 and
1105 A. The gratings are holographically ruled to largely correct for
astigmatism and to minimize scattered light. The microchannel plate detectors
have KBr photocathodes and use photon counting to achieve good quantum
efficiency with low background signal. The sensitivity is sufficient to examine
reddened lines of sight within the Milky Way as well as active galactic nuclei
and QSOs for absorption line studies of both Milky Way and extra-galactic gas
clouds. This spectral region contains a number of key scientific diagnostics,
including O VI, H I, D I and the strong electronic transitions of H2 and HD.

</DOC>
<DOC>
<DOCNO> 12004 </DOCNO>
Discrete breathers in classical spin lattices


  Discrete breathers (nonlinear localised modes) have been shown to exist in
various nonlinear Hamiltonian lattice systems. In the present paper we study
the dynamics of classical spins interacting via Heisenberg exchange on spatial
$d$-dimensional lattices (with and without the presence of single-ion
anisotropy). We show that discrete breathers exist for cases when the continuum
theory does not allow for their presence (easy-axis ferromagnets with
anisotropic exchange and easy-plane ferromagnets). We prove the existence of
localised excitations using the implicit function theorem and obtain necessary
conditions for their existence. The most interesting case is the easy-plane one
which yields excitations with locally tilted magnetisation. There is no
continuum analogue for such a solution and there exists an energy threshold for
it, which we have estimated analytically. We support our analytical results
with numerical high-precision computations, including also a stability analysis
for the excitations.

</DOC>
<DOC>
<DOCNO> 178647 </DOCNO>
Correlations and the Dirac Structure of the Nucleon Self-Energy


  The Dirac structure of the nucleon self-energy in symmetric nuclear matter as
well as neutron matter is derived from a realistic meson exchange model for the
nucleon-nucleon (NN) interaction. It is demonstrated that the effects of
correlations on the effective NN interaction in the nuclear medium can be
parameterized by means of an effective meson exchange. This analysis leads to a
very intuitive interpretation of correlation effects and also provides an
efficient parametrization of an effective interaction to be used in
relativistic structure calculations for finite nuclei.

</DOC>
<DOC>
<DOCNO> 120474 </DOCNO>
Extreme Scattering Events: An Observational Summary


  We review observational constraints on the structures responsible for extreme
scattering events, focussing on a series of observations of the quasar PKS
1741-038. VLA observations were conducted to search for changes in the rotation
measure and H I absorption during the ESE, while VLBI observations sought
ESE-induced changes in the source's image. No RM changes were found implying
B_|| < 12 mG, and no H I opacity changes were found implying N(H I) < 6.4 x
10^{17} cm^{-2}. No multiple imaging was observed, but the diameter of the
source increased by 0.7 mas, contrary to what is predicted by simple refractive
lens modeling of ESEs. We summarize what these limits imply about the structure
responsible for this ESE.

</DOC>
<DOC>
<DOCNO> 100805 </DOCNO>
The second cohomology of small irreducible modules for simple algebraic


  Let G be a simple, simply connected and connected algebraic group over an
algebraically closed field of characteristic p>0, and let V be a rational
G-module such that dim V <= p. According to a result of Jantzen, V is
completely reducible, and H^1(G,V)=0. In this paper we show that H^2(G,V) = 0
unless some composition factor of V is a non-trivial Frobenius twist of the
adjoint representation of G.

</DOC>
<DOC>
<DOCNO> 122037 </DOCNO>
Evolution of O Abundance Relative to Fe


  We present a three-component mixing model for the evolution of O abundance
relative to Fe, taking into account the contributions of the first very massive
(> 100 solar masses) stars formed from Big Bang debris. We show that the
observations of O and Fe abundances in metal-poor stars in the Galaxy by
Israelian et al. and Boesgaard et al. can be well represented both
qualitatively and quantitatively by this model. Under the assumption of an
initial Fe ([Fe/H] = -3) and O inventory due to the prompt production by the
first very massive stars, the data at -3 < [Fe/H] < -1 are interpreted to
result from the addition of O and Fe only from type II supernovae (SNII) to the
prompt inventory. At [Fe/H] = -1, SNII still contribute O while both SNII and
type Ia supernovae contribute Fe. During this later stage, (O/Fe) sharply drops
off to an asymptotic value of 0.8(O/Fe)_sun. The value of (O/Fe) for the prompt
inventory at [Fe/H] = -3 is found to be (O/Fe) = 20(O/Fe)_sun. This result
suggests that protogalaxies with low ``metallicities'' should exhibit high
values of (O/Fe). The C/O ratio produced by the first very massive stars is
expected to be much less than 1 so that all the C should be tied up as CO and
that C dust and hydrocarbon compounds should be quite rare at epochs
corresponding to [Fe/H] < -3.

</DOC>
<DOC>
<DOCNO> 84666 </DOCNO>
Space-times admitting a three-parameter similarity group


  Spacetimes admitting a similarity group are considered. Amongst them, special
attention is given to the 3-parameter ones. A classification of such spacetimes
is given based on the Bianchi type of the similarity group $H_3$, and the
general form of the metric is provided in each case assuming the orbits are
non-null.

</DOC>
<DOC>
<DOCNO> 11635 </DOCNO>
Phenomenological Theory for Phase Turbulence in Rayleigh-B\'{e}nard


  We present a phenomenological theory for phase turbulence (PT) in
Rayleigh-B\'{e}nard convection, based on the generalized Swift-Hohenberg model.
We apply a Hartree-Fock approximation to PT and conjecture a scaling form for
the structure factor $S(k)$ with respect to the correlation length $\xi_2$. We
hence obtain {\it analytical} results for the time-averaged convective current
$J$ and the time-averaged mean square vorticity $\Omega$. We also define
power-law behaviors such as $J \sim \epsilon^\mu$, $\Omega \sim
\epsilon^\lambda$ and $\xi_2 \sim \epsilon^{-\nu}$, where $\epsilon$ is the
control parameter. We find from our theory that $\mu = 1$, $\nu \ge 1/2$ and
$\lambda = 2 \mu + \nu$. These predictions, together with the scaling
conjecture for $S(k)$, are confirmed by our numerical results.

</DOC>
<DOC>
<DOCNO> 84684 </DOCNO>
SO(4,C)-covariant Ashtekar-Barbero gravity and the Immirzi parameter


  An so(4,C)-covariant hamiltonian formulation of a family of generalized
Hilbert-Palatini actions depending on a parameter (the so called Immirzi
parameter) is developed. It encompasses the Ashtekar-Barbero gravity which
serves as a basis of quantum loop gravity. Dirac quantization of this system is
constructed. Next we study dependence of the quantum system on the Immirzi
parameter. The path integral quantization shows no dependence on it. A way to
modify the loop approach in the accordance with the formalism developed here is
briefly outlined.

</DOC>
<DOC>
<DOCNO> 101513 </DOCNO>
Fredholm theory of the linearized ${{\bar \partial}}$-operator and


  In this paper, we established Fredholm theory of the linearized ${{\bar
\partial}}$-operator and studied the additivity of its index.

</DOC>
<DOC>
<DOCNO> 101859 </DOCNO>
An explicit construction of the McKay correspondence for A-Hilb C^3


  For a finite Abelian subgroup A of SL(3,C), Ito and Nakajima established an
isomorphism between the K-theory of Nakamura's A-Hilbert scheme A-Hilb C^3 and
the representation ring of A. This leads to a basis of the rational cohomology
of A-Hilb C^3 in one-to-one correspondence with the irreducible representations
of A. In this paper we construct an explicit basis of the integral cohomology
of A-Hilb C^3 in one-to-one correspondence with the irreducible representations
of A. Our approach is elementary, leading to some lovely pictures of toric fans
decorated with characters of A.

</DOC>
<DOC>
<DOCNO> 10282 </DOCNO>
Bloch Walls and Macroscopic String States in Bethe's solution of the


  We present a calculation of the lowest excited states of the Heisenberg
ferromagnet in 1-d for any wave vector. These turn out to be string solutions
of Bethe's equations with a macroscopic number of particles in them. These are
identified as generalized quantum Bloch wall states, and a simple physical
picture provided for the same.

</DOC>
<DOC>
<DOCNO> 11415 </DOCNO>
On-site magnetization in open antiferromagnetic chains: a classical


  The response of an open spin chain with isotropic antiferromagnetic
interactions to a uniform magnetic field is studied by classical Monte Carlo
simulations. It is observed how the induced on-site magnetization is non
uniform, due to the occurrence of edge staggered terms which decay
exponentially over a distance equal to the zero field correlation length of the
infinite chain. The total magnetic moment associated to each staggered term is
found to be about half of the original single-spin magnitude and to decrease as
the inverse of temperature (i.e. to behave as a Curie-like moment). The
numerical results are compared to recent NMR findings in spinless-doped
Y(2)BaNiO(5); the remarkable agreement found shows that, for temperatures above
the Haldane gap, the classical approach gives a correct picture of the boundary
effects observed in the Heisenberg S=1 chain.

</DOC>
<DOC>
<DOCNO> 121360 </DOCNO>
The Durham/UKST Galaxy Redshift Survey - VII. Redshift-space distortions


  We investigate the effect of redshift-space distortions in the power spectrum
parallel and perpendicular to the observer's line of sight, P(k_par,k_perp),
using the optically selected Durham/UKST Galaxy Redshift Survey. On small,
non-linear scales anisotropy in the power-spectrum is dominated by the galaxy
velocity dispersion; the `Finger of God' effect. On larger, linear scales
coherent peculiar velocities due to the infall of galaxies into overdense
regions are the main cause of anisotropy. According to gravitational
instability theory these distortions depend only on the density and bias
parameters via beta. Geometrical distortions also occur if the wrong cosmology
is assumed, although these would be relatively small given the low redshift of
the survey. To quantify these effects, we assume the real-space power spectrum
of the APM Galaxy Survey, and fit a simple model for the redshift-space and
geometrical distortions. Assuming a flat Omega = 1 universe, we find values for
the one-dimensional pairwise velocity dispersion of sigma_p = 410 +- 170 km/s,
and beta = 0.38 +- 0.17. An open Omega = 0.3, and a flat Omega = 0.3, Lambda =
0.7 universe yield sigma_p = 420 km/s, beta = 0.40, and sigma_p = 440 km/s,
beta = 0.45 respectively, with comparable errors. These results are consistent
with estimates using the two-point galaxy correlation function, xi(sigma,pi),
and favour either a low-density universe with Omega ~ 0.3 if galaxies trace the
underlying mass distribution, or a bias factor of b ~ 2.5 if Omega = 1.

</DOC>
<DOC>
<DOCNO> 169715 </DOCNO>
Nonextensive approach to decoherence in quantum mechanics


  We propose a nonextensive generalization (q parametrized) of the von Neumann
equation for the density operator. Our model naturally leads to the phenomenon
of decoherence, and unitary evolution is recovered in the limit of q -> 1. The
resulting evolution yields a nonexponential decay for quantum coherences, fact
that might be attributed to nonextensivity. We discuss, as an example, the loss
of coherence observed in trapped ions.

</DOC>
<DOC>
<DOCNO> 120500 </DOCNO>
The Infall Region of Abell 576: Independent Mass and Light Profiles


  We describe observations of the nearby cluster of galaxies A576 beyond the
virial radius and into the infall region. Using 1057 redshifts, we use the
infall pattern in redshift space to determine the mass profile of A576 to a
radius of ~4 Mpc/h. This mass estimation technique makes no assumptions about
the equilibrium state of the cluster. Within 1 Mpc/h, the mass profile we
derive exceeds that determined from X-ray observations by a factor of 2.5. At
\~2.5 Mpc/h, however, the mass profile agrees with virial mass estimates. Our
mass profile is consistent with a NFW or Hernquist profile, but it is
inconsistent with an isothermal sphere. R-band images of a $3^\circ x 3^\circ$
region centered on the cluster allow an independent determination of the
cluster light profile. We calculate the integrated mass-to-light ratio as a
function of cluster radius; it decreases smoothly from the core to ~4 Mpc/h.
The differential dM/dL_R profile decreases more steeply; we find M/L_R ~100 h
at ~4 Mpc/h, in good agreement with the mass-to-light ratios of individual
galaxies. This value implies $\Omega_m \lesssim 0.4$ at 95% confidence. For a
Hernquist model, the best-fit mass profiles differ from the observed surface
number density of galaxies; the galaxies have a larger scale radius than the
mass. This result is consistent with the centrally peaked $M/L_R$ profile.
Similarly, the scale radius of the light profile is larger than that of the
mass profile. We discuss some potential systematic effects; none can easily
reconcile our results with a constant mass-to-light ratio. (abstract edited)

</DOC>
<DOC>
<DOCNO> 39760 </DOCNO>
Enhancing the physical significance of Frequentist confidence intervals


  It is shown that all the Frequentist methods are equivalent from a
statistical point of view, but the physical significance of the confidence
intervals depends on the method. The Bayesian Ordering method is presented and
confronted with the Unified Approach in the case of a Poisson process with
background. Some criticisms to both methods are answered. It is also argued
that a general Frequentist method is not needed.

</DOC>
<DOC>
<DOCNO> 119563 </DOCNO>
Gravitational Lensing by Nearby Clusters of Galaxies


  We present an estimation of the expected number of arcs and arclets in a
sample of nearby (z<0.1) clusters of galaxies, that takes into account the
magnitude limit of the objects as well as seeing effects. We show that strong
lensing effects are not common, but also they are not as rare as usually
stated. Indeed, for a given cluster, they present a strong dependence with the
magnitude limit adopted in the analysis and the seeing of the observations. We
also describe the procedures and results of a search for lensing effects in a
sample of 33 clusters spanning the redshift range of 0.014 to 0.076,
representative of the local cluster distribution. This search produced two arc
candidates. The first one is in A3408 (z=0.042), the same arc previously
discovered by Campusano & Hardy (1996), with z=0.073 and associated to the
brightest cluster galaxy. The second candidate is in the cluster A3266
(z=0.059) and is near a bright elliptical outside the cluster center, requiring
the presence of a very massive sub-structure around this galaxy to be produced
by gravitational lensing.

</DOC>
<DOC>
<DOCNO> 151072 </DOCNO>
Dynamics and topology of the gauge-invariant gauge field in two-color


  A nonlinear integral equation that is responsible for the implementation of
the non-Abelian Gauss's law is applied to an investigation of the topological
features of two-color QCD and to a discussion of their relation to QCD
dynamics. We also draw a parallel between the nonuniqueness of the solutions of
the equations that govern the gauge-invariant gauge field and Gribov copies.

</DOC>
<DOC>
<DOCNO> 150806 </DOCNO>
Renormalization Group Flows on D3 branes at an Orbifolded Conifold


  We consider D3-branes at an orbifolded conifold whose horizon ${X_5}$
resolves into a smooth Einstein manifold which joins several copies of ${\bf
T}^{1,1}$. We describe in details the resolution of the singular horizon
${X_5}$ and describe different types of two-cycles appearing in the resolution.
For a large number of D3 branes, the AdS/CFT conjecture becomes a duality
between type IIB string theory on $AdS_5 \times {X_5} $ and the ${\cal N} = 1$
field theory living on the D3 branes. We study the fractional branes as small
perturbations of the string background and we reproduce the logarithmic flow of
field theory couplings by studying fluxes of NS-NS and R-R two forms through
different 2-cycles of the resolved horizon.

</DOC>
<DOC>
<DOCNO> 121457 </DOCNO>
OB Associations, Open Clusters, and the Luminosity Calibration of the


  In the context of the luminosity calibration of the nearer stars I discuss
the Hipparcos results on distances to nearby OB associations and open clusters.
The shortcomings and assumptions in the analyses used to derive these results
are pointed out and for the open clusters a comparison is made with results
obtained from main sequence fitting. I conclude that given the considerable
uncertainties in the latter technique there is no convincing evidence that the
Hipparcos based distances to open clusters beyond the Hyades should not be
trusted.

</DOC>
<DOC>
<DOCNO> 10462 </DOCNO>
Universal distribution of transparencies in highly conductive


  We report the observation of the universal distribution of transparencies,
predicted by Schep and Bauer [Phys. Rev. Lett. {\bf 78}, 3015 (1997)] for dirty
sharp interfaces, in uniform Nb/AlO$_x$/Nb junctions with high specific
conductance ($10^8$ Ohm$^{-1}$cm$^{-2}$). Experiments used the BCS density of
states in superconducting niobium for transparency distribution probing.
Experimental results for both the dc $I-V$ curves at magnetic-field-suppressed
supercurrent and the Josephson critical current in zero magnetic field coincide
remarkably well with calculations based on the multimode theory of multiple
Andreev reflections and the Schep-Bauer distribution.

</DOC>
<DOC>
<DOCNO> 102909 </DOCNO>
Linear functionals on idempotent spaces: an algebraic approach


  In this paper, we present an algebraic approach to idempotent functional
analysis, which is an abstract version of idempotent analysis. The basic
concepts and results are expressed in purely algebraic terms. We consider
idempotent versions of certain basic results of linear functional analysis,
including the theorem on the general form of a linear functional and the
Hahn-Banach and Riesz-Fischer theorems.

</DOC>
<DOC>
<DOCNO> 117997 </DOCNO>
The robust detection of stars on CCD images


  Two parameters are developed to analyze the CCD images from ground-based
and/or space telescopes. The first parameter, deduced from the intensity
profile of the object sharp, is useful to resolve stars and hot pixels. The
second parameter shape distinguishes the stars from the background cosmic-ray
events using geometric characteristics defined by its shapes. The parameters
are applied to a simulated OMC/INTEGRAL image and a HST image.

</DOC>
<DOC>
<DOCNO> 151392 </DOCNO>
BPS Solutions and New Phases of Finite-Temperature Strings


  All high-temperature phases of the known N=4 superstrings in five dimensions
can be described by the universal thermal potential of an effective
four-dimensional supergravity. This theory, in addition to three moduli s, t,
u, contains non-trivial winding modes that become massless in certain regions
of the thermal moduli space, triggering the instabilities at the Hagedorn
temperature. In this context, we look for exact domain wall solutions of first
order BPS equations. These solutions preserve half of the supersymmetries, in
contrast to the usual finite-temperature weak-coupling approximation, and as
such may constitute a new phase of finite-temperature superstrings. We present
exact solutions for the type-IIA and type-IIB theories and for a self-dual
hybrid type-II theory. While for the heterotic case the general solution cannot
be given in closed form, we still present a complete picture and a detailed
analysis of the behaviour around the weak and strong coupling limits and around
certain critical points. In all cases these BPS solutions have no instabilities
at any temperature. Finally, we address the physical meaning of the resulting
geometries within the contexts of supergravity and string theory.

</DOC>
<DOC>
<DOCNO> 11801 </DOCNO>
Filling Control of the Mott Insulator Ca2RuO4


  We have grown single crystals of electron doping system Ca2-xLaxRuO4 (0.00 <=
x <= 0.20) by a floating zone method. The first order metal/non-metal
transition and canted antiferromagnetic ordering occur for 0.00 < x < 0.15,
similar to those in the bandwidth controlled system Ca2-xSrxRuO4 (CSRO).
However, comparing with CSRO, we found a rather different metallic ground state
adjacent to the non-metallic ground state with canted antiferromagnetic order.
Instead of short-range antiferromagnetic correlation found in CSRO (0.20 <= x <
0.50), the metallic ground state of the present system is characterized by
strong ferromagnetic correlation.

</DOC>
<DOC>
<DOCNO> 11634 </DOCNO>
Discussion of a spin-cluster model for the low temperature phase of


  We discuss magnetic excitations of a spin-cluster model which has been
suggested to describe the low temperature phase of alpha'-NaV_2O_5. This model
fulfills all symmetry criteria proposed by recent x-ray investigations. We find
that this model is not able to describe the occurence of two well separated
magnon lines perpendicular to the ladder direction as observed in INS
experiments. We suggest further experimental analysis to generally distinguish
between models with double reflection or inversion symmetry.

</DOC>
<DOC>
<DOCNO> 122617 </DOCNO>
Detectability of the Parallax-induced Deviations in the Astrometric


  The uncertainty of the lens mass can be substantially reduced if it is
determined from the lens proper motion obtained from astrometric measurements
of the source image centroid shifts, $\vdelta\vtheta_c$, by using high
precision interferometers. However, for the complete resolution of the lens
parameter degeneracy it is required to determine the lens parallax by measuring
the parallax-induced deviations in the centroid shifts trajectory, $\vDelta
\vdelta \vtheta_c$. In this paper, we investigate the detectabilities of
$\vdelta\vtheta_c$ and $\vDelta\vdelt\vtheta_c$ by determining the
distributions of the maximum centroid shifts and the average maximum deviations
expected for different types of Galactic microlensing events caused by various
masses. From this investigation, we find that as long as sources are bright
enough for astrometric observations it is expected that $\vdeltavxtheta_c$ for
most events caused by masses greater than 0.1 M_\odot regardless of the event
types can be easily detected from observations by using not only the Space
Interfeormetry Mission (SIM, with a detection threshold ~ 3 \mu-as) but also
the ground-based interferometers (with a threshold ~30 \mu-as). However,
detection of $\vDelta\vdelta\vtheta_c$ from ground-based observations will be
difficult for nearly all Galactic bulge self-lensing events, and will be
restricted only for small fractions of disk-bulge and halo-LMC events, for
which the deviations are relatively large. From observations by using the SIM,
on the other hand, detecting $\vDelta\vdelta\vtheta_c$ will be possible for
majority of disk-bulge and halo-LMC events and even for some fraction of bulge
self-lensing events. For the complete resolution of the lens parameter
degeneracy, therefore, SIM observations (or equivalent) will be essential.

</DOC>
<DOC>
<DOCNO> 10152 </DOCNO>
Third Order Renormalization Group applied to the attractive


  We consider a Callan-Symanzik and a Wilson Renormalization Group approach to
the infrared problem for interacting fermions in one dimension with
backscattering. We compute the third order (two-loop) approximation of the beta
function using both methods and compare it with the well known multiplicative
Gell-Mann Low approach. We point out a previously unnoticed qualitative
dependence of the third order fixed point on an arbitrary dimensionless
parameter, which strongly suggest the spurious nature of the fixed point.

</DOC>
<DOC>
<DOCNO> 123133 </DOCNO>
The COMPTEL instrumental line background


  The instrumental line background of the Compton telescope COMPTEL onboard the
Compton Gamma-Ray Observatory is due to the activation and/or decay of many
isotopes. The major components of this background can be attributed to eight
individual isotopes, namely 2D, 22Na, 24Na, 28Al, 40K, 52Mn, 57Ni, and 208Tl.
The identification of instrumental lines with specific isotopes is based on the
line energies as well as on the variation of the event rate with time,
cosmic-ray intensity, and deposited radiation dose during passages through the
South-Atlantic Anomaly. The characteristic variation of the event rate due to a
specific isotope depends on its life-time, orbital parameters such as the
altitude of the satellite above Earth, and the solar cycle. A detailed
understanding of the background contributions from instrumental lines is
crucial at MeV energies for measuring the cosmic diffuse gamma-ray background
and for observing gamma-ray line emission in the interstellar medium or from
supernovae and their remnants. Procedures to determine the event rate from each
background isotope are described, and their average activity in spacecraft
materials over the first seven years of the mission is estimated.

</DOC>
<DOC>
<DOCNO> 151018 </DOCNO>
Chamseddine, Fr\"ohlich, Grandjean Metric and Localized Higgs Coupling


  We propose a geometrized Higgs mechanism based on the gravitational sector in
the Connes-Lott formulation of the standard model, which has been constructed
by Chamseddine, Fr$\ddot{o}$hlic and Grandjean. The point of our idea is that
Higgs-like couplings depend on the local coordinates of the four-dimensional
continuum,$M_4$. The localized couplings can be calculated by the Wilson loops
of the $U(1)_{EM}$ gauge field and the connection, which is defined on
$Z_2\times{M_4}$.

</DOC>
<DOC>
<DOCNO> 40323 </DOCNO>
mb from ALEPH and comparison with other LEP experiments


  I will review the measurements of the $b$-quark mass performed by ALEPH and
DELPHI. A large set of observables has been used together with detailed studies
on jet algorithms. Very clear effects due to the $b$-quark mass running are
observed. Comparing with the determinations at the $\Upsilon(4S)$ threshold,
the measurements of the running $b$-quark mass at the $Z$ pole are consistent
with the predicted evolution from QCD.

</DOC>
<DOC>
<DOCNO> 117183 </DOCNO>
SLC Final Performance and Lessons


  The Stanford Linear Collider (SLC) was the first prototype of a new type of
accelerator, the electron-positron linear collider. Many years of dedicated
effort were required to understand the physics of this new technology and to
develop the techniques for maximizing performance. Key issues were emittance
dilution, stability, final beam optimization and background control. Precision,
non-invasive diagnostics were required to measure and monitor the beams
throughout the machine. Beam-based feedback systems were needed to stabilize
energy, trajectory, intensity and the final beam size at the interaction point.
A variety of new tuning techniques were developed to correct for residual
optical or alignment errors. The final focus system underwent a series of
refinements in order to deliver sub-micron size beams. It also took many
iterations to understand the sources of backgrounds and develop the methods to
control them. The benefit from this accumulated experience was seen in the
performance of the SLC during its final run in 1997-98. The luminosity
increased by a factor of three to 3*10**30 and the 350,000 Z data sample
delivered was nearly double that from all previous runs combined.

</DOC>
<DOC>
<DOCNO> 11552 </DOCNO>
Magnetic fluctuations in the classical XY model: the origin of an


  We study the probability density function for the fluctuations of the
magnetic order parameter in the low temperature phase of the XY model of finite
size. In two-dimensions this system is critical over the whole of the low
temperature phase. It is shown analytically and without recourse to the scaling
hypothesis that, in this case, the distribution is non-Gaussian and of
universal form, independent of both system size and critical exponent $\eta$.
An exact expression for the generating function of the distribution is
obtained, which is transformed and compared with numerical data from high
resolution molecular dynamics and Monte Carlo simulations. The calculation is
extended to general dimension and an exponential tail is found in all
dimensions less than four, despite the fact that critical fluctuations are
limited to D=2. These results are discussed in the light of similar behaviour
observed in models of interface growth and for dissipative systems driven into
a non-equilibrium steady state.

</DOC>
<DOC>
<DOCNO> 11845 </DOCNO>
Superfluid Hydrodynamics of an Electron Gas in a Superstrong Magnetic


  We derive the equations of hydrodynamics of a fully polarized electron gas
placed in a strong magnetic field. These equations reveal the existence of
solitons - immobile or propagating domain wall-like defects whose plane is
perpendicular to the field direction. The solitons are used to construct weakly
excited states, and novel nonuniform persistent current states of the system.

</DOC>
<DOC>
<DOCNO> 8491 </DOCNO>
The XX-model with boundaries. Part II: Finite size scaling and partition


  We compute the continuum limit of the spectra for the XX-model with arbitrary
complex boundary fields. In the case of hermitian boundary terms one obtains
the partition functions of the free compactified boson field on a cylinder with
Neumann-Neumann, Dirichlet-Neumann or Dirichlet-Dirichlet boundary conditions.
This applies also for certain non-hermitian boundaries. For special cases we
also compute the free surface energy. For certain non-hermitian boundary terms
the results are more complex.Here one obtains logarithmic corrections to the
free surface energy. The asymmetric version of the XX-model with boundaries
(this includes the Dzyaloshinsky-Moriya interaction)is also discussed.

</DOC>
<DOC>
<DOCNO> 69948 </DOCNO>
Future High Q^2 Deep Inelastic Scattering at HERA


  The luminosity of the electron-proton collider, HERA, will be increased by a
factor of five during the long shutdown starting September 2000. At the same
time longitudinal lepton beam polarisation will be provided for the collider
experiments H1 and ZEUS. These far reaching upgrades to the machine will be
matched by upgrades to the detectors. The result will be a unique facility for
the study of the structure of the proton and the nature of the strong and
electroweak interactions. The physics potential of the upgraded accelerator is
discussed here.

</DOC>
<DOC>
<DOCNO> 7805 </DOCNO>
Symmetry Does Not Allow Canting of Spins in La_{1.4}Sr_{1.6}Mn_2O_7


  We analyze the symmetry of all possible magnetic structures of bilayered
manganites La_{2-2x}Sr_{1+2x}Mn_2O_7 with doping 0.3 <= x < 0.5 and formulate a
corresponding Landau theory of the phase transitions involved. It is shown that
canting of spins is not allowed at x=0.3 though is at x=0.4. The observed
magnetic reflections from the sample with x=0.3 may be described as arising
from two spatially distributed phases with close transition temperatures but
different easy axes and ranges of stability. Experimental results are revisited
on the basis of the theoretical findings.

</DOC>
<DOC>
<DOCNO> 69312 </DOCNO>
J/\Psi \to \phi \pi \pi (K \bar{K}) decays, chiral dynamcis and OZI


  We have studied the invariant mass distributions of the \pi\pi and K \bar{K}
systems for invariant masses up to 1.2 GeV from the J/\Psi \to \phi
\pi\pi(K\bar{K}) decays. The approach exploits the connection between these
processes and the \pi\pi and K\bar{K} strange and non-strange scalar form
factors by considering the \phi meson as a spectator. The calculated scalar
form factors are then matched with the ones from next-to-leading order chiral
perturbation theory, including the calculation of the the K\bar{K} scalar form
factors. Final state interactions in the J/\Psi \to \phi \pi\pi (K\bar{K})
processes are taken into account as rescattering effects in the system of the
two pseudoscalar mesons. A very good agreement with the experimental data from
DM2 and MARK-III is achieved. Furthermore, making use of SU(3) symmetry, the
S-wave contribution to the \pi^+\pi^- event distribution in the J/\Psi \to
\omega \pi^+\pi^- reaction is also given and the data up to energies of about
0.7 GeV are reproduced. These decays of the J/\Psi to a vector and a pair of
pseudoscalars turn out to be very sensitive to OZI violating physics which we
parametrize in terms of a direct OZI violation parameter and the chiral
perturbation theory low energy constants L_4^r and L_6^r. These constants all
come out very different from zero, lending further credit to the statement that
the OZI rule is not operative in the scalar 0^{++} channel.

</DOC>
<DOC>
<DOCNO> 80760 </DOCNO>
First order phase transition of the q-state Potts model in two


  We have calculated the large-$q$ series of the energy cumulants, the
magnetization cumulants and the correlation length at the first order phase
transition point both in the ordered and disordered phases for the $q$-state
Potts model in two dimensions. The series enables us to estimate the numerical
values of the quantities more precisely by a factor of $10^2 - 10^4$ than the
Monte Carlo simulations. From the large-$q$ series of the eigenvalues of the
transfer matrix, we also find that the excited states form a continuum spectrum
and there is no particle state at the first order phase transition point.

</DOC>
<DOC>
<DOCNO> 10466 </DOCNO>
The structure of fluid trifluoromethane and methylfluoride


  We present hard X-ray and neutron diffraction measurements on the polar
fluorocarbons HCF3 and H3CF under supercritical conditions and for a range of
molecular densities spanning about a factor of ten. The Levesque-Weiss-Reatto
inversion scheme has been used to deduce the site-site potentials underlying
the measured partial pair distribution functions. The orientational
correlations between adjacent fluorocarbon molecules -- which are characterized
by quite large dipole moments but no tendency to form hydrogen bonds -- are
small compared to a highly polar system like fluid hydrogen chloride. In fact,
the orientational correlations in HCF3 and H3CF are found to be nearly as small
as those of fluid CF4, a fluorocarbon with no dipole moment.

</DOC>
<DOC>
<DOCNO> 122662 </DOCNO>
Type Ia Supernovae and Remnant Neutron Stars


  On the basis of the current observational evidence, we put forward the case
that the merger of two CO white dwarfs produces both a Type Ia supernova
explosion and a stellar remnant, the latter in the form of a magnetar. The
estimated occurrence rates raise the possibility that many, if not most, SNe Ia
might result from white dwarf mergers.

</DOC>
<DOC>
<DOCNO> 67707 </DOCNO>
Particle Multiplicities and Thermalization in High Energy Collisions


  We investigate the conditions under which particle multiplicities in high
energy collisions are Boltzmann distributed, as is the case for hadron
production in e^+e^-, pp, p-pbar and heavy ion collisions. We show that the
apparent "temperature" governing this distribution does not necessarily imply
equilibrium (thermal or chemical) in the usual sense, as we explain. We discuss
an explicit example using tree level amplitudes for N photon production in
which a Boltzmann-like distribution is obtained without any equilibration. We
argue that the failure of statistical techniques based on free particle
ensembles may provide a signal for collective phenomena (such as large shifts
in masses and widths of resonances) related to the QCD phase transition.

</DOC>
<DOC>
<DOCNO> 169937 </DOCNO>
Enhanced Quantum Estimation via Purification


  We analyze the estimation of a finite ensemble of quantum bits which have
been sent through a depolarizing channel. Instead of using the depolarized
qubits directly, we first apply a purification step and show that this improves
the fidelity of subsequent quantum estimation. Even though we lose some qubits
of our finite ensemble the information is concentrated in the remaining
purified ones.

</DOC>
<DOC>
<DOCNO> 83430 </DOCNO>
Reduction of Intermediate Alphabets in Finite-State Transducer Cascades


  This article describes an algorithm for reducing the intermediate alphabets
in cascades of finite-state transducers (FSTs). Although the method modifies
the component FSTs, there is no change in the overall relation described by the
whole cascade. No additional information or special algorithm, that could
decelerate the processing of input, is required at runtime. Two examples from
Natural Language Processing are used to illustrate the effect of the algorithm
on the sizes of the FSTs and their alphabets. With some FSTs the number of arcs
and symbols shrank considerably.

</DOC>
<DOC>
<DOCNO> 71974 </DOCNO>
Pion-Lambda-Sigma Coupling Extracted from Hyperonic Atoms


  The latest measurements of the atomic level width in Sigma-hyperonic Pb atom
offer the most accurate datum in the region of low-energy Sigma-hyperon
physics. Atomic widths are due to the conversion of Sigma-nucleon into
Lambda-nucleon. In high angular momentum states this conversion is dominated by
the one-pion exchange. A joint analysis of the data of the scattering of
negative-Sigma on proton converting into a Lambda and a neutron and of the
atomic widths allows to extract a pseudovector pion-hyperon-Sigma coupling
constant of 0.048 with a statistical error of +-0.005 and a systematic one of
+-0.004. This corresponds to a pseudoscalar coupling constant of 13.3 with a
statistical uncertainty of 1.4 and a systematic one of 1.1.

</DOC>
<DOC>
<DOCNO> 151434 </DOCNO>
Marginal Stability and the Metamorphosis of BPS States


  We discuss the restructuring of the BPS spectrum which occurs on certain
submanifolds of the moduli/parameter space -- the curves of the marginal
stability (CMS) -- using quasiclassical methods. We argue that in general a
`composite' BPS soliton swells in coordinate space as one approaches the CMS
and that, as a bound state of two `primary' solitons, its dynamics in this
region is determined by non-relativistic supersymmetric quantum mechanics. Near
the CMS the bound state has a wave function which is highly spread out.
Precisely on the CMS the bound state level reaches the continuum, the composite
state delocalizes in coordinate space, and restructuring of the spectrum can
occur. We present a detailed analysis of this behavior in a two-dimensional N=2
Wess-Zumino model with two chiral fields, and then discuss how it arises in the
context of `composite' dyons near weak coupling CMS curves in N=2
supersymmetric gauge theories. We also consider cases where some states become
massless on the CMS.

</DOC>
<DOC>
<DOCNO> 40267 </DOCNO>
Neutrinos from SN1987A, Earth matter effects and the LMA solution of the


  We study properties of the oscillation effects in the matter of the Earth on
antineutrino fluxes from supernovae. We show that these effects can provide
explanation of the difference in the energy spectra of the events detected by
Kamiokande-2 and IMB detectors from SN1987A as well as the absence of
high-energy events with $E\gta 40$ MeV. This explanation requires the neutrino
oscillation parameters $\Delta m^2$ and $\sin^2 2\theta $ to be in the region
of the LMA solution of the solar neutrino problem and the normal mass hierarchy
if $|U_{e 3}|^2\gta 10^{-3}$. The hierarchy can be inverted if $|U_{e 3}|^2\ll
10^{-3}$. The solution of the solar neutrino problem based on
$\nu_e$-conversion to a pure sterile state is disfavoured by SN1987A data.

</DOC>
<DOC>
<DOCNO> 70944 </DOCNO>
Searching for Extra Dimensions in the Early Universe


  We examine recent large cosmological $Z_{c} = \Delta \lambda /\lambda$ quasar
spectra for possible evidence of extra spatial dimensions ($D = 3+\epsilon,
\epsilon << 1$) in the early universe. The complete Lyman alpha (Ly$_{\alpha}$)
to Lyman epsilon (Ly$_{\epsilon}$) $\epsilon$-dependent quantum mechanical
wavelength transitions are given. Our methodology is to use Lyman beta
(Ly$_{\beta}$) as the anchor, and identify Lyman gamma (Ly$_{\gamma}$), Lyman
delta (Ly$_{\delta}$) and Ly$_{\epsilon}$, Finally we give an $\epsilon$
corrected value for Ly$_{\alpha}$. By computing the variance of the hydrogen
line population, we use the statistical Z-test to give confidence estimates for
$D = 3 + \epsilon$ in the early universe.

</DOC>
<DOC>
<DOCNO> 102850 </DOCNO>
K-Theory Past and Present


  A brief account of K-theory written in honour of Friedrich Hirzebruch

</DOC>
<DOC>
<DOCNO> 71858 </DOCNO>
A General MSSM Parameter Scan


  The excluded tan(beta) range and Higgs boson mass regions in the framework of
the Minimal Supersymmetric extension of the Standard Model (MSSM) depend on
several parameters. The Higgs boson masses, cross-sections and branching
fractions have been determined including two-loop diagrammatic calculations.
The limits obtained with a more general scan over the parameter space of the
MSSM are compared with those in the so-called benchmark scenario. The
combination of the searches for Higgs particles in the 1999 data collected by
the DELPHI collaboration at center-of-mass energies between 191.6 and 201.7 GeV
allows stringent limits to be set in combination with previous DELPHI results.
In addition, an interpretation in the framework of the general MSSM scan of the
2000 LEP data at the hightest energies between 201.7 and 209.0 GeV is given. We
show that the current data for the HZ and hA production can be comfortably
accommodated in the MSSM.

</DOC>
<DOC>
<DOCNO> 10423 </DOCNO>
Independent freezing of charge and spin dynamics in La1.5Sr0.5CoO4


  We present elastic and quasielastic neutron scattering measurements
characterizing peculiar short-range charge-orbital and spin order in the
layered perovskite material La1.5Sr0.5CoO4. We find that below Tc~750 K holes
introduced by Sr doping lose mobility and enter a statically ordered {\it
charge glass} phase with loosely correlated checkerboard arrangement of empty
and occupied d{3z2-r2} orbitals (Co3+ and Co2+). The dynamics of the resultant
mixed spin system is governed by the anisotropic nature of the crystal-field
Hamiltonian and the peculiar exchange pattern produced by the orbital order. It
undergoes a {\it spin freezing} transition at much a lower temperature, Ts~30
K.

</DOC>
<DOC>
<DOCNO> 10277 </DOCNO>
Systematic study of Ga$_{1-x}$In$_x$As self-assembled quantum wires with


  A systematic theoretical study of the electronic and optical properties of
Ga$_{1-x}$In$_x$As self-assembled quantum-wires (QWR's) made of short-period
superlattices (SPS) with strain-induced lateral ordering is presented. The
theory is based on the effective bond-orbital model (EBOM) combined with a
valence-force field (VFF) model. Valence-band anisotropy, band mixing, and
effects due to local strain distribution at the atomistic level are all taken
into account. Several structure models with varying degrees of alloy mixing for
lateral modulation are considered. A valence force field model is used to find
the equilibrium atomic positions in the QWR structure by minimizing the lattice
energy. The strain tensor at each atomic (In or Ga) site is then obtained and
included in the calculation of electronic states and optical properties. It is
found that different local arrangement of atoms leads to very different strain
distribution, which in turn alters the optical properties. In particular, we
found that in model structures with thick capping layer the electron and hole
are confined in the Ga-rich region and the optical anisotropy can be reversed
due to the variation of lateral alloying mixing, while for model structures
with thin capping layer the electron and hole are confined in the In-rich
region, and the optical anisotropy is much less sensitive to the lateral alloy
mixing.

</DOC>
<DOC>
<DOCNO> 8974 </DOCNO>
Nonequilibrium Thermodynamics of Colloids


  The common rules of classical nonequilibrium thermodynamics do not allow an
Onsager coefficient like the viscosity to depend on the shear rate. Such a
dependence is experimentally well documented, however. In this paper it is
shown, using nonequilibrium thermodynamics alone, how it is possible that the
effective viscosity coefficient of an isotropic colloidal system depends on
both the shear rate and the frequency.

</DOC>
<DOC>
<DOCNO> 101100 </DOCNO>
Convergence of zeta functions of graphs


  The $L^2$-zeta function of an infinite graph Y (defined previously in a ball
around zero) has an analytic extension. For a tower of finite graphs covered by
Y, the normalized zeta functions of the finite graphs converge to the
$L^2$-zeta function of Y.

</DOC>
<DOC>
<DOCNO> 100745 </DOCNO>
Unitary spherical highest weight representations


  In this paper we give a classification of the $H$-spherical unitary highest
weight representations of a hermitian Lie group $G$.

</DOC>
<DOC>
<DOCNO> 40137 </DOCNO>
Final-state Rescattering Effects on B_d-->\pi\pi Decays and CP Violation


  The significance of final-state interactions in B_d-->\pi\pi decays is
phenomenologically demonstrated by taking elastic \pi\pi--\pi\pi and inelastic
\pi\pi--D\bar{D} rescattering effects into consideration. We find that the
present experimental data on B^0_d-->\pi^+\pi^- can well be understood in this
approach without fine-tuning of the input parameters, and large CP-violating
asymmetries are expected to manifest themselves in such charmless rare
processes.

</DOC>
<DOC>
<DOCNO> 8962 </DOCNO>
Spin-triplet superconductivity due to antiferromagnetic spin-fluctuation


  A mechanism leading to the spin-triplet superconductivity is proposed based
on the antiferromagnetic spin fluctuation. The effects of anisotropy in spin
fluctuation on the Cooper pairing and on the direction of d vector are examined
in the one-band Hubbard model with RPA approximation. The gap equations for the
anisotropic case are derived and applied to Sr_2RuO_4. It is found that a
nesting property of the Fermi surface together with the anisotropy leads to the
triplet superconductivity with the d=z(sin{k_x}\pm isin{k_y}), which is
consistent with experiments.

</DOC>
<DOC>
<DOCNO> 72240 </DOCNO>
B-physics constraints on baryon number violating couplings: grand


  We investigate the role that baryon number violating interactions may play in
$B$ phenomenology. Present in various grand unified theories, supersymmetric
theories with R-parity violation and composite models, a diquark state could be
quite light. Using the data on B decays as well as $B - {\bar B}$ mixing, we
find strong constraints on the couplings that such a light diquark state may
have with the Standard Model quarks.

</DOC>
<DOC>
<DOCNO> 117062 </DOCNO>
Experimental Evidence of Near-field Superluminally Propagating


  A simple experiment is presented which indicates that electromagnetic fields
propagate superluminally in the near-field next to an oscillating electric
dipole source. A high frequency 437MHz, 2 watt sinusoidal electrical signal is
transmitted from a dipole antenna to a parallel near-field dipole detecting
antenna. The phase difference between the two antenna signals is monitored with
an oscilloscope as the distance between the antennas is increased. Analysis of
the phase vs distance curve indicates that superluminal transverse electric
field waves (phase and group) are generated approximately one-quarter
wavelength outside the source and propagate toward and away from the source.
Upon creation, the transverse waves travel with infinite speed. The outgoing
transverse waves reduce to the speed of light after they propagate about one
wavelength away from the source. The inward propagating transverse fields
rapidly reduce to the speed of light and then rapidly increase to infinite
speed as they travel into the source. The results are shown to be consistent
with standard electrodynamic theory.

</DOC>
<DOC>
<DOCNO> 83253 </DOCNO>
One-Dimensional Peg Solitaire


  We solve the problem of one-dimensional peg solitaire. In particular, we show
that the set of configurations that can be reduced to a single peg forms a
regular language, and that a linear-time algorithm exists for reducing any
configuration to the minimum number of pegs.

</DOC>
<DOC>
<DOCNO> 71113 </DOCNO>
Hadronic cross-sections in gamma gamma processes and the next linear


  In this note we address the issue of theoretical estimates of the hadronic
cross-sections for \gamgam processes. We compare the predictions of the minijet
model with data as well as other models, highlighting the band of uncertainties
in the theoretical predictions as well as those in the final values of the
$\sigma (\gamgam \go {\rm hadrons})$ extracted from the data. We find that the
rise of $\sigma_{\gamma \gamma}^{\rm tot}$ with energy shown in the latest
\gamgam data is in tune with the faster rise expected in the Eikonal Minijet
Models (EMM). We present an estimate of the accuracy with which this
cross-section needs to be measured, in order to distinguish between the
different theoretical models which try to `explain ' the rise of total
cross-sections with energy. We find that the precision of measurement required
to distinguish the EMM type models from the proton-like models, for $300 <
\sqrt{s}_{\gamgam} < 500$ GeV, is $\lsim 20 %$, whereas to distinguish between
various proton-like models or among the different parametrizations of the EMM,
a precision of $\lsim 8-9 %$ or $\lsim 6-7%$ respectively, is required. We also
comment briefly on the implications of these predictions for hadronic
backgrounds at the next linear collider (NLC) to be run in the \gamgam mode or
\eplem mode.

</DOC>
<DOC>
<DOCNO> 122811 </DOCNO>
Sensitivity of an Imaging Space Infrared Interferometer


  We study the sensitivities of space infrared interferometers. We formulate
the signal-to-noise ratios of infrared images obtained by aperture synthesis in
the presence of source shot noise, background shot noise and detector read
noise. We consider the case in which n beams are pairwise combined at n(n-1)/2
detectors, and the case in which all the n beams are combined at a single
detector. We apply the results to future missions, Terrestrial Planet Finder
and Darwin. We also discuss the potential of a far-infrared interferometer for
a deep galaxy survey.

</DOC>
<DOC>
<DOCNO> 71953 </DOCNO>
Thermal Production of Gravitinos


  We evaluate the gravitino production rate in supersymmetric QCD at high
temperature to leading order in the gauge coupling. The result, which is
obtained by using the resummed gluon propagator, depends logarithmically on the
gluon plasma mass. As a byproduct, a new result for the axion production rate
in a QED plasma is obtained. The implicatons for the cosmological dark matter
problem are briefly discussed, in particular the intriguing possibility that
gravitinos are the dominant part of cold dark matter.

</DOC>
<DOC>
<DOCNO> 40396 </DOCNO>
On the quantum loop weak interaction corrections at high energies


  We perform comparative analyses of quantum loop corrections to some
observationally important two- and three-point Green functions within two
distinct symmetry-breaking mechanisms. It appears that the existing high-energy
data, neutrino experiments and present astrophysical and cosmological
constraints strongly disfavour the Higgs mechanism, while the introduction of
the noncontractible space as a symmetry-breaking mechanism can resolve all
known problems and puzzles of fundamental interactions.

</DOC>
<DOC>
<DOCNO> 8675 </DOCNO>
On the dynamics of coupled S=1/2 antiferromagnetic zig-zag chains


  We investigate the elementary excitations of quasi one-dimensional S=1/2
systems built up from zig-zag chains with general isotropic exchange constants,
using exact (Lanczos) diagonalization for 24 spins and series expansions
starting from the decoupled dimer limit. For the ideal one-dimensional zig-zag
chain we discuss the systematic variation of the basic (magnon) triplet
excitation with general exchange parameters and in particular the presence of
practically flat dispersions in certain regions of phase space. We extend the
dimer expansion in order to include the effects of 3D interactions on the
spectra of weakly interacting zig-zag chains. In an application to KCuCl_3 we
show that this approach allows to determine the exchange interactions between
individual pairs of spins from the spectra as determined in recent neutron
scattering experiments.

</DOC>
<DOC>
<DOCNO> 40046 </DOCNO>
Event Shapes and Power Corrections in e+e- Annihilation


  The effects of the hadronisation of partons on the distribution of event
shape observables are associated with corrections which are suppressed by
reciprocal powers of the energy scale of the process. The correction is
determined by one non-calculable parameter \alpha_0 for which an universal
value of 0.5 +/- 20% is found from the investigation of the distribution of
event shape observables and their mean values measured in e^+e^- annihilation.

</DOC>
<DOC>
<DOCNO> 169866 </DOCNO>
Comment on the temperature dependence of the Casimir force


  Linear in temperature correction to the Casimir force is discussed. The
correction is important for small separations between bodies tested in the
recent experiments and disappears in the case of perfect conductors.

</DOC>
<DOC>
<DOCNO> 169872 </DOCNO>
Elementary Excitations in Trapped BEC and Zero Mode Problem


  We propose a natural expansion of the atomic field operator in studying
elementary excitations in trapped Bose-Einstein Condensation (BEC) system near
T=0K. Based on this expansion, a system of coupled equations for elementary
excitations, which is equivalent to the standard linearized GP equation, is
given to describe the collective excitation of BEC in a natual way.
Applications of the new formalism to the homogeneous case emphasize on the zero
mode and its relevant ground state of BEC.

</DOC>
<DOC>
<DOCNO> 12609 </DOCNO>
Autosolitons in trapped Bose-Einstein condensates with two- and


  In this work, we consider the conditions for the existence of autosolitons,
in trapped Bose-Einstein condensates with attractive atomic interactions.
First, the variational approach is employed to estimate the stationary
solutions for the three-dimensional Gross-Pitaevskii equation with trap
potential, linear atomic feeding from the thermal cloud and two- and three-body
inelastic processes. Next, by using exact numerical calculations, we show that
the variational approach gives reliable analytical results. We also discuss the
possible observation of autosolitons in experiments with Lithium-7.

</DOC>
<DOC>
<DOCNO> 118487 </DOCNO>
Metallicity of Red Giants in the Galactic Bulge from Near-Infrared


  We present K-band spectra of more than 110 M giants in Galactic bulge fields
interior to -4 degrees and as close as 0.2 degrees of the Galactic Center. From
the equivalent widths of three features in these spectra, EW(Na),EW(Ca), and
EW(CO) we calculate [Fe/H] for the stars with a calibration derived from
globular clusters Stephens et al (2000). The mean [Fe/H] for each field is in
good agreement with the results from Frogel et al. (1999) based on the slope of
the giant branch method. We find no evidence for a metallicity gradient along
the minor or major axes of the inner bulge (R < 0.6 kpc). A metallicity
gradient along the minor axis, found earlier, arises when fields located at
larger galactic radius are included. However, these more distant fields are
located outside of the infrared bulge defined by the COBE/DIRBE observations.
We compute the [Fe/H] distribution for the inner bulge and find a mean value of
-0.21 dex with a full width dispersion of 0.30 dex, close to the values found
for Baade's Window (BW) by Sadler et al. (1996) and to a theoretical prediction
for a bulge formed by dissipative collapse Molla et al (2000).

</DOC>
<DOC>
<DOCNO> 12566 </DOCNO>
"Slimming" of power law tails by increasing market returns


  We introduce a simple generalization of rational bubble models which removes
the fundamental problem discovered by [Lux and Sornette, 1999] that the
distribution of returns is a power law with exponent less than 1, in
contradiction with empirical data. The idea is that the price fluctuations
associated with bubbles must on average grow with the mean market return r.
When r is larger than the discount rate r_delta, the distribution of returns of
the observable price, sum of the bubble component and of the fundamental price,
exhibits an intermediate tail with an exponent which can be larger than 1. This
regime r>r_delta corresponds to a generalization of the rational bubble model
in which the fundamental price is no more given by the discounted value of
future dividends. We explain how this is possible. Our model predicts that, the
higher is the market remuneration r above the discount rate, the larger is the
power law exponent and thus the thinner is the tail of the distribution of
price returns.

</DOC>
<DOC>
<DOCNO> 170078 </DOCNO>
Dynamical description of the buildup process in resonant tunneling:


  The buildup process of the probability density inside the quantum well of a
double-barrier resonant structure is studied by considering the analytic
solution of the time dependent Schr\"{o}dinger equation with the initial
condition of a cutoff plane wave. For one level systems at resonance condition
we show that the buildup of the probability density obeys a simple charging up
law, $| \Psi (\tau) / \phi | =1-e^{-\tau /\tau_0},$ where $\phi$ is the
stationary wave function and the transient time constant $\tau_0$ is exactly
two lifetimes. We illustrate that the above formula holds both for symmetrical
and asymmetrical potential profiles with typical parameters, and even for
incidence at different resonance energies. Theoretical evidence of a crossover
to non-exponential buildup is also discussed.

</DOC>
<DOC>
<DOCNO> 69242 </DOCNO>
Rigorous Effective Field Theory Study on Pion Form Factor


  We study $e^+e^-\to\pi^+\pi^-$ cross section and phase shift of $I=l=1$
$\pi-\pi$ scattering below 1GeV in framework of chiral constituent quark model.
The results including all order contribution of the chiral perturbation
expansion and all one-loop effects of pseudoscalar mesons, but without any
adjust parameters. Width of $\rho$ predicted by the model strongly depends on
transition momentum-square $q^2$. We show that the mass pamameter of
$\rho$-meson in its propagator is very different from its physical mass due to
momentum-dependent width of $\rho$. The mass difference between $\rho^0$ and
$\omega$ are predicted successfully. The rigorous theoretical prediction on
$e^+e^-\to\pi^+\pi^-$ cross section and the phase shift in $I=l=1$ $\pi-\pi$
scattering agree with data excellentlly.

</DOC>
<DOC>
<DOCNO> 100740 </DOCNO>
New Ideas for Resolution of Singularities in Arbitrary Characteristic


  This is the manuscript for Proceedings of International Conference and
Workshop on Valuation Theory held at University of Saskachewan, Canada in 1999.
I have succeeded in showing that any two-dimensional hypersurface singularities
of germs of varieties in any characteristic can be resolved by iterated
monoidal transformations with centers in smooth subvarieties. The new proof for
the two-dimensional case depends on new ideas. Ideas are essentially different
from Abhyankar's one in 1956 and Lipman's one in 1978. It seems to be possible
to generalize the new proof into higher dimensional cases, if we add several
ideas further. In this article I try to explain my new ideas rather than
partial result I explained at the conference.

</DOC>
<DOC>
<DOCNO> 122249 </DOCNO>
Photoevaporating flows from the cometary knots in the Helix nebula (NGC


  We explain the Ha emission of the cometary knots in the Helix Nebula (NGC
7293) with an analytical model that describes the emission of the head of the
globules as a photoevaporated flow produced by the incident ionizing radiation
of the central star.We compare these models with the Ha emission obtained from
the HST archival images of the Helix Nebula. From a comparison of the Ha
emission with the predictions of the analytical model we obtain a rate of
ionizing photons from the central star of about 5e45 s^-1, which is consistent
with estimates based on the total Hb flux of the nebula. We also model the
tails of the cometary knots as a photoevaporated wind from a neutral shadow
region produced by the diffuse ionizing photon field of the nebula. A
comparison with the HST images allows us to obtain a direct determination of
the value of the diffuse ionizing flux. We compare the ratio of diffuse to
direct stellar flux as a function of radius inside an HII region with those
obtained from the observational data through the analytical tail and head wind
model. The agreement of this model with the values determined from the
observations of the knots is excellent.

</DOC>
<DOC>
<DOCNO> 102913 </DOCNO>
Model of a quantum particle in spacetime


  Doplicher, Fredenhagen, and Roberts (1994, 1995) proposed a simple model of a
particle in quantum spacetime. We give a new formulation of the model and
propose some small changes and additions which improve the physical
interpretation. In particular, we show that the internal degrees of freedom e
and m of the particle represent external forces acting on the particle. To
obtain this result we follow a constructive approach. The model is formulated
as a covariance system. It has projective representations in which not only the
spacetime coordinates but also the conjugated momenta are two-by-two
noncommuting. These momenta are of the form P_mu-(b/c)A_mu, where b is the
charge of the particle. The electric and magnetic fields obtained from the
vector potential A_mu coincide with the variables e and m postulated by DFR.
Similarly, the spacetime position operators are of the form Q_mu-(al^2/hbar c)
Omega_mu where a is a generalized charge, l a fundamental length, and with
vector potentials Omega_mu which are in some sense dual w.r.t. the A_mu.

</DOC>
<DOC>
<DOCNO> 14021 </DOCNO>
Existence and stability of atomic-molecular Bose-Einstein condensates


  We analyze the model of an atomic Bose-Einstein condensate (BEC)
parametrically coupled to a molecular BEC via a photoassociation process. We
show that an interplay of nonlinear inter- and intra-species interactions leads
to the formation of mutually trapped states of a hybrid condensate, which are
spatially localized even without a trap. The untrapped atomic-molecular
condensates with a large number of atoms in either fraction are shown to be
dynamically stable in the framework of a mean field theory.

</DOC>
<DOC>
<DOCNO> 84875 </DOCNO>
Gauge and Cutoff Function Dependence of the Ultraviolet Fixed Point in


  The exact renormalization group equation for pure quantum gravity is derived
for an arbitrary gauge parameter in the space-time dimension $d=4$. This
equation is given by a non-linear functional differential equation for the
effective average action. An action functional of the effective average action
is approximated by the same functional space of the Einstein-Hilbert action.
  From this approximation, $\beta$-functions for the dimensionless Newton
constant and cosmological constant are derived non-perturbatively. These are
used for an analysis of the phase structure and the ultraviolet non-Gaussian
fixed point of the dimensionless Newton constant. This fixed point strongly
depends on the gauge parameter and the cutoff function. However, this fixed
point exists without these ambiguities, except for some gauges. Hence, it is
possible that pure quantum gravity in $d=4$ is an asymptotically safe theory
and non-perturbatively renormalizable.

</DOC>
<DOC>
<DOCNO> 119601 </DOCNO>
RATAN-600 - VLA - BTA-6m ("BIG TRIO") Project: multicolour studying of


  Powerful radio galaxies belong to the population of massive stellar systems
that can be picked at high redshifts. With measured redshift, morphology and
age determination these objects can help greatly in understanding of the way of
formation and evolution of giant elliptical galaxies with massive Black Holes
in the Early Universe. We presents some recent results of study of the sample
of 105 faint steep spectrum radio sources from RATAN-600 RC catalogue.
  All the objects has been mapped with the VLA and optical identification have
been carried out with the 6m BTA telescope. Using multicolour CCD photometry in
B,V,R_c,I_c bands photometric redshift and age of stellar population are
estimated for a subsample of 50 FRII and CSS radio galaxies. RC J0105+0501 is a
very probable candidate for radio galaxy at z ~ 3.5.
  Distribution of objects on colour-colour and magnitude-redshift diagrams
shows a rough agreement with expectations of theoretical models of SED
evolution for giant elliptical galaxies. On the [m_R - z_{phot}] diagram two
populations of faint (m_R = 22^m-24^m) radio galaxies are possibly revealed.
The first population at z~ 1 consists of mainly old (a half with age >= 5 Gyr)
and large (LAS~20") objects, the second one at z = 1.5 - 3.5 includes both
younger (<= 3 Gyr) and smaller (LAS ~ 5") objects.
  There are 12 more faint or still undetected (m_R >= 24.5^m) sources in the
sample which may presumably be a very distant radio galaxies (z>3.5) or
intermediate redshift old or dusty ones.

</DOC>
<DOC>
<DOCNO> 117958 </DOCNO>
A study of young radio-loud AGN using space-VLBI


  Gigahertz Peaked Spectrum (GPS) sources form a key element in the study of
the onset and evolution of radio-loud AGN, since they are most likely the young
counterparts of extended radio sources. Here we discuss space-VLBI observations
of GPS sources, which enable us to obtain unprecedented angular resolution at
frequencies near their spectral turnovers. Observed peak brightness
temperatures of Log[T]=10.5-11 Kelvin indicate that synchrotron self absorption
is responsible for their spectral turnovers. This is in close agreement with
previous size - spectral turnover statistics for GPS sources. The combination
of these new space-VLBI observations with ground-based VLBI observations taken
at an earlier epoch, confirm the young ages for the most compact GPS galaxies
of several hundred years.

</DOC>
<DOC>
<DOCNO> 151315 </DOCNO>
Renormalizability of the open string sigma model and emergence of


  Rederiving the one-loop divergences for the most general coupling of the open
string sigma model by the heat kernel technique, we distinguish the classical
background field from the mean field of the effective action. The latter is
arbitrary, i.e. does not fulfil the boundary conditions. As a consequence a new
divergent counter term strongly suggests the introduction of another external
one-form field (beside the usual gauge field), coupled to the normal derivative
at the boundary. Actually such a field has been proposed in the literature for
different reasons, but its full impact never seems to have thoroughly
investigated before. The beta function for the resulting renormalizable model
is calculated and the consequences are discussed, including the ones for the
Born-Infeld action. The most exciting property of the new coupling is that it
enters the coefficient in front of the normal derivative in Neumann boundary
conditions. For certain values of the background fields this coefficient
vanishes, leading to Dirichlet boundary conditions. This provides a natural
mechanism for the emergence of D-branes.

</DOC>
<DOC>
<DOCNO> 10288 </DOCNO>
Quantum Calogero-Moser Models: Integrability for all Root Systems


  The issues related to the integrability of quantum Calogero-Moser models
based on any root systems are addressed. For the models with degenerate
potentials, i.e. the rational with/without the harmonic confining force, the
hyperbolic and the trigonometric, we demonstrate the following for all the root
systems: (i) Construction of a complete set of quantum conserved quantities in
terms of a total sum of the Lax matrix (L), i.e. (\sum_{\mu,\nu\in{\cal
R}}(L^n)_{\mu\nu}), in which ({\cal R}) is a representation space of the
Coxeter group. (ii) Proof of Liouville integrability. (iii) Triangularity of
the quantum Hamiltonian and the entire discrete spectrum. Generalised Jack
polynomials are defined for all root systems as unique eigenfunctions of the
Hamiltonian. (iv) Equivalence of the Lax operator and the Dunkl operator. (v)
Algebraic construction of all excited states in terms of creation operators.
These are mainly generalisations of the results known for the models based on
the (A) series, i.e. (su(N)) type, root systems.

</DOC>
<DOC>
<DOCNO> 123282 </DOCNO>
Maximum Particle Energies by Fermi Acceleration and the Origin of Cosmic


  We derive the maximum accelerated particle energy from first-order and
second-order Fermi acceleration at nonrelativistic and relativistic shocks for
explosions taking place in a uniform surrounding medium. Second-order
stochastic processes in relativistic flows are shown to be capable of
accelerating cosmic rays to ultra-high energies. Cosmic rays above the knee of
the cosmic ray spectrum can be accelerated by the second-order Fermi mechanism
in relativistic flows, such as those occuring in gamma-ray bursts and unusual
supernovae like SN 1998bw.

</DOC>
<DOC>
<DOCNO> 11893 </DOCNO>
Ultrafast Coulomb-induced dynamics of 2D magnetoexcitons


  We study theoretically the ultrafast nonlinear optical response of quantum
well excitons in a perpendicular magnetic field. We show that for
magnetoexcitons confined to the lowest Landau levels, the third-order
four-wave-mixing (FWM) polarization is dominated by the exciton-exciton
interaction effects. For repulsive interactions, we identify two regimes in the
time-evolution of the optical polarization characterized by exponential and
{\em power law} decay of the FWM signal. We describe these regimes by deriving
an analytical solution for the memory kernel of the two-exciton wave-function
in strong magnetic field. For strong exciton-exciton interactions, the decay of
the FWM signal is governed by an antibound resonance with an
interaction-dependent decay rate. For weak interactions, the continuum of
exciton-exciton scattering states leads to a long tail of the time-integrated
FWM signal for negative time delays, which is described by the product of a
power law and a logarithmic factor. By combining this analytic solution with
numerical calculations, we study the crossover between the exponential and
non-exponential regimes as a function of magnetic field. For attractive
exciton-exciton interaction, we show that the time-evolution of the FWM signal
is dominated by the biexcitonic effects.

</DOC>
<DOC>
<DOCNO> 67764 </DOCNO>
Instability of Classic Rotational Motion for Three-String Baryon Model


  The dynamics of baryon string model Y (three-string) is considered with using
the approach that implies defining a classical motion of the system on the base
of given initial position and initial velocities of string points. The analysis
resulted, in particular, in the necessity of regarding more wide (than it was
supposed earlier) class of parametrizations of the world surface for the
adequate description of the three-string model. This approach let us to
ascertain that the classic rotational motions (flat uniform rotations) for this
string configuration are unstable. Any small asymmetric disturbances grow and
inevitably result in falling a quark into the junction.

</DOC>
<DOC>
<DOCNO> 120674 </DOCNO>
Infrared Star Count Models and Their Application to the Subaru Deep


  We construct infrared star count models of the Galaxy applicable at faint
magnitudes. In addition to dwarfs and subdwarfs, we also take into account L
dwarfs, T dwarfs, and white dwarfs of both disk and halo. As a test case of the
models, we analyze the infrared imaging data at J and K' obtained during the
Subaru Deep Field Survey to study stellar objects. Infrared star count models
we have obtained predict that the Next Generation Space Telescope will
primarily see T dwarfs, M subdwarfs, and old halo white dwarfs at faint
magnitudes.

</DOC>
<DOC>
<DOCNO> 121665 </DOCNO>
The Globular Cluster System in the Outer Regions of NGC 4472


  We have undertaken a study of the globular cluster (GC) systems of a large
sample of elliptical and spiral galaxies in order to test predictions of galaxy
formation models. Here we present results for the giant Virgo elliptical NGC
4472 (M49). The galaxy was observed in 3 filters (BVR) using the Mosaic Imager
on the Kitt Peak 4-m telescope. Our images roughly double the radial coverage
of previous CCD observations of NGC 4472. We have combined the Mosaic data with
spectroscopic data and HST data in order to fully characterize the level of
contamination in our GC sample. The radial profile of the GC system is fit
fairly well by a de Vaucouleurs law out to 17 arc minutes (~80 kpc), but the
profile falls slightly below the de Vaucouleurs law between 17 and 23 arc
minutes. The bimodal color distribution observed in past studies appears in our
data. We find a small metallicity gradient in the inner 8 arc minutes of the GC
system due to the increasing ratio of blue to red clusters. The gradient
vanishes, however, when the entire radial extent of the data is taken into
account. We estimate a total of 5,900 GCs in NGC 4472 out to 23 arc minutes,
yielding a specific frequency of 3.6+/-0.6 within this radius. This value is
smaller than that found by previous studies of NGC 4472. We examine the
implications of these results with regard to predictions made by four galaxy
formation models, and find that all four models have at least one inconsistency
with the data. [abridged]

</DOC>
<DOC>
<DOCNO> 12560 </DOCNO>
Quasiparticle kinetic equation in a trapped Bose gas at low temperatures


  Recently the authors used the Kadanoff-Baym non-equilibrium Green's function
formalism to derive kinetic equation for the non-condensate atoms, in
conjunction with a consistent generalization of the Gross-Pitaevskii equation
for the Bose condensate wavefunction. This work was limited to high
temperatures, where the excited atoms could be described by a
 Hartree-Fock particle-like spectrum. We present the generalization of this
recent work to low temperatures, where the single-particle spectrum is now
described by the Bogoliubov-Popov approximation. We derive a kinetic equation
for the quasiparticle distribution function with collision integrals describing
scattering between quasiparticles and the condensate atoms. From the general
expression for the collision integral for the scattering between quasiparticle
excitations, we find the quasiparticle distribution function corresponding to
local equilibrium. This expression includes a quasiparticle chemical potential
that controls the non-diffusive equilibrium between condensate atoms and the
quasiparticle excitations. We also derive a generalized Gross-Pitaevskii
equation for the condensate wavefunction that includes the damping effects due
to collisions between atoms in the condensate and the thermally excited
quasiparticles. For a uniform Bose gas, our kinetic equation for the thermally
excited quasiparticles reduces to that found by Eckern as well as Kirkpatrick
and Dorfman.

</DOC>
<DOC>
<DOCNO> 9062 </DOCNO>
Probing superconducting phase fluctuations from the current noise


  We study the current noise spectra of a tunnel junction of a metal with
strong pairing phase fluctuation and a superconductor. It is shown that there
is a characteristic peak in the noise spectrum at the intrinsic Josephson
frequency $\omega_J=2eV$ when $\omega_J$ is smaller than the pairing gap but
larger than the pairing scattering rate. In the presence of an AC voltage, the
tunnelling current noise shows a series of characteristic peaks with increasing
DC voltage. Experimental observation of these peaks will give direct evidence
of the pair fluctuation in the normal state of high-$T_c$ superconductors and
from the half width of the peaks the pair decay rate can be estimated.

</DOC>
<DOC>
<DOCNO> 117738 </DOCNO>
Stellar Dynamics in the Galactic centre: Proper Motions and Anisotropy


  We report a new analysis of stellar dynamics in the Galactic centre, based on
improved sky and LOS velocities for >100 stars within a few arcsec of SgrA*.
Overall the motions do not deviate strongly from isotropy. For 32 stars with
all 3 components determined the absolute, LOS and sky velocities agree well, as
for a spherical cluster. The projected radial and tangential motions of all 104
pm stars are also consistent with overall isotropy. However, the projected
velocities of the young, early type stars have a strong radial dependence. Most
of the bright HeI stars 1-10" from SgrA* are on tangential orbits. This
anisotropy of the HeI stars and most of the brighter IRS16 complex members is
largely caused by a CW and counter-rotating, coherent rotation pattern. The
overall rotation of the young star cluster probably is a remnant of the angular
momentum in the cloud these stars formed from. The fainter, fast stars within
\~1" of SgrA* appear to be largely moving on radial or very elliptical orbits.
We have not detected nonlinear motion for any of them. Most of the SgrA*
cluster members also are on CW orbits. Spectroscopy shows them to be early type
stars. We propose that the SgrA* cluster stars are those members of the early
type cluster with small angular momentum which can plunge to the vicinity of
SgrA*. Our anisotropy-independent estimate of the Sun-GC distance is 7.8-8.2
kpc (+/- 0.9 kpc). We include velocity anisotropy in estimating the central
mass distribution. We confirm previous conclusions that a compact central mass
concentration is present and dominates the potential from 0.01-1 pc. The
central mass ranges from 2.6-3.3E6 M_sun. (abridged)

</DOC>
<DOC>
<DOCNO> 10374 </DOCNO>
Effective interactions between like-charged macromolecules


  We investigate, within a local density functional theory formalism, the
interactions between like-charged polyions immersed in a confined electrolyte.
We obtain a simple condition for a repulsive effective pair potential, that can
be related to the thermodynamic stability criterion of the uncharged
counterpart of microscopic species constituting the electrolyte. Under the same
condition, the phenomenon of charge inversion (over-charging), where the
polyion bare charge is over-screened by its electric double layer, is shown to
be impossible. These results hold beyond standard mean-field theories (such as
Poisson-Boltzmann or Modified Poisson-Boltzmann approaches).

</DOC>
<DOC>
<DOCNO> 120502 </DOCNO>
Optical spectroscopy of galaxies in the direction of the Virgo cluster


  Optical spectroscopy of 76 galaxies, 48 of which are projected in the
direction of the Virgo cluster and 28 onto the Coma-A1367 supercluster, is
reported. Adding these new measurements to those found in the literature, the
redshift completeness in the Virgo region becomes 92% at B_T<=16.0 and 68% at
B_T<=18.0. The one of CGCG galaxies in the direction of the Coma-A1367
supercluster becomes 98%. The Virgo cluster membership estimates obtained on
morphological grounds by Binggeli et al. (1985) are confirmed in all cases.
However, several "possible members" classified as BCD (if in the cluster) are
found instead to be giant emission-line galaxies in the background of the Virgo
cluster

</DOC>
<DOC>
<DOCNO> 11360 </DOCNO>
The dynamics of a hole in a CuO_4 plaquette: electron energy-loss


  We have measured the energy and momentum dependent loss function of Li_2CuO_2
single crystals by means of electron energy-loss spectroscopy in transmission.
Using the same values for the model parameters, the low-energy features of the
spectrum as well as published Cu 2p_(3/2) x-ray photoemission data of Li_2CuO_2
are well described by a cluster model that consists of a single CuO_4 plaquette
only. This demonstrates that charge excitations in Li_2CuO_2 are strongly
localized.

</DOC>
<DOC>
<DOCNO> 101328 </DOCNO>
The Muhly-Renault-Williams theorem for Lie groupoids and its classical


  A theorem of Muhly-Renault-Williams states that if two locally compact
groupoids with Haar system are Morita equivalent, then their associated
convolution C*-algebras are strongly Morita equivalent.
 We give a new proof of this theorem for Lie groupoids. Subsequently, we prove
a counterpart of this theorem in Poisson geometry: If two Morita equivalent Lie
groupoids are s-connected and s-simply connected, then their associated Poisson
manifolds (viz. the dual bundles to their Lie algebroids) are Morita equivalent
in the sense of P. Xu.

</DOC>
<DOC>
<DOCNO> 122296 </DOCNO>
Model Independent Primordial Power Spectrum from Maxima, Boomerang, and


  A model-independent determination of the primordial power spectrum of matter
density fluctuations could uniquely probe physics of the very early universe,
and provide powerful constraints on inflationary models. We parametrize the
primordial power spectrum $A_s^2(k)$ as an arbitrary function, and deduce its
binned amplitude from the cosmic microwave background radiation anisotropy
(CMB) measurements of Maxima, Boomerang, and DASI. We find that for a flat
universe with $A_s^2(k)=1$ (scale-invariant) for scales $k<0.001 $h/Mpc, the
primordial power spectrum is marginally consistent with a scale-invariant
Harrison-Zeldovich spectrum. However, we deduce a rise in power compared to a
scale-invariant power spectrum for $0.001 h/{Mpc} \la k \la 0.01 h/{Mpc}$. Our
results are consistent with large-scale structure data, and seem to suggest
that the current observational data allow for the possibility of unusual
physics in the very early universe.

</DOC>
<DOC>
<DOCNO> 120027 </DOCNO>
The central part of the young open cluster NGC 6383


  The spectral and extinction properties of 14 pre-main sequence candidates in
the central part of the very young open cluster NGC 6383 were investigated.
None of these stars shows evidence for anomalous circumstellar extinction.
However, six out of 14 programme stars do show an infrared excess, indicative
of the presence of circumstellar dust, heated up by the central star. One of
these stars (number 4), also shows Halpha in emission and shows some
indications for the presence of circumstellar gas in its spectrum, and might
therefore be a newly identified Herbig Ae star.

</DOC>
<DOC>
<DOCNO> 119366 </DOCNO>
Complete RXTE Spectral Observations of the Black Hole X-ray Nova XTE


  We report on the X-ray spectral behavior of the exceptionally bright X-ray
nova XTE J1550-564 during its 1998-99 outburst. Our study is based on 209
pointed observations using the PCA and HEXTE instruments onboard the Rossi
X-ray Timing Explorer spanning 250 days and covering the entire double-peaked
eruption that occurred from 1998 September until 1999 May. The spectra are fit
to a model including multicolor blackbody disk and power-law components. The
source is observed in the very high and high/soft outburst states of black hole
X-ray novae. During the very high state, when the power-law component dominated
the spectrum, the inner disk radius is observed to vary by more than an order
of magnitude; the radius decreased by a factor of 16 in one day during a 6.8
Crab flare. If the larger of these observed radii is taken to be the last
stable orbit, then the smaller observed radius would imply that the inner edge
of the disk is inside the event horizon! However, we conclude that the apparent
variations of the inner disk radius observed during periods of increased
power-law emission are probably caused by the failure of the multicolor
disk/power-law model; the actual physical radius of the inner disk may remain
fairly constant. This interpretation is supported by the fact that the observed
inner disk radius remains approximately constant over 120 days in the high
state, when the power-law component is weak, even though the disk flux and
total flux vary by an order of magnitude. The mass of the black hole inferred
by equating the approximately constant inner disk radius observed in the
high/soft state with the last stable orbit for a Schwarzschild black hole is
M_BH = 7.4 M_sun (D/6 kpc) (cos i)^{-1/2}.

</DOC>
<DOC>
<DOCNO> 178436 </DOCNO>
Pion Interferometry From A Relativistic Fluid With A First Order Phase


  We investigate pion source sizes through the Yano-Koonin-Podgoretski\u{\i}
(YKP) parametrization for the Hanbury-Brown Twiss (HBT) effect in the CERN-SPS
158 GeV/A central collisions. We calculate two-particle correlation functions
numerically based on a (3+1)-dimensional relativistic hydrodynamics with a
first order phase transition and analyze the pair momentum dependence of the
HBT radii extracted from the YKP parametrization in detail. We find that even
in the case of a first order phase transition, expansion and the surface
dominant freeze-out make the source in the hydrodynamical model opaque
significantly. Consequently, the interpretation of the temporal radius
parameter as the time duration becomes unavailable for the hydrodynamical
model.

</DOC>
<DOC>
<DOCNO> 102322 </DOCNO>
Two-Parameter Quantum Groups and Drinfel'd Doubles


  We investigate two-parameter quantum groups corresponding to the general
linear and special linear Lie algebras gl_n and sl_n. We show that these
quantum groups can be realized as Drinfel'd doubles of certain Hopf subalgebras
with respect to Hopf pairings. Using the Hopf pairing, we construct a
corresponding R-matrix and a quantum Casimir element. We discuss isomorphisms
among these quantum groups and connections with multiparameter quantum groups.

</DOC>
<DOC>
<DOCNO> 101166 </DOCNO>
An excursion from enumerative goemetry to solving systems of polynomial


  Solving a system of polynomial equations is a ubiquitous problem in the
applications of mathematics. Until recently, it has been hopeless to find
explicit solutions to such systems, and mathematics has instead developed deep
and powerful theories about the solutions to polynomial equations. Enumerative
Geometry is concerned with counting the number of solutions when the
polynomials come from a geometric situation and Intersection Theory gives
methods to accomplish the enumeration.
   We use Macaulay 2 to investigate some problems from enumerative geometry,
illustrating some applications of symbolic computation to this important
problem of solving systems of polynomial equations. Besides enumerating
solutions to the resulting polynomial systems, which include overdetermined,
deficient, and improper systems, we address the important question of real
solutions to these geometric problems.
  The text contains evaluated Macaulay 2 code to illuminate the discussion.
This is a chapter in the forthcoming book "Computations in Algebraic Geometry
with Macaulay 2", edited by D. Eisenbud, D. Grayson, M. Stillman, and B.
Sturmfels. While this chapter is largely expository, the results in the last
section concerning lines tangent to quadrics are new.

</DOC>
<DOC>
<DOCNO> 118785 </DOCNO>
Estimation of steady-state basic parameters of stars


  From a minimum of total energy of celestial bodies, their basic parameters
are obtained. The steady-state values of the mass, radius, and temperature of
stars and white dwarfs, as well as masses of pulsars are calculated. The
luminosity and giromagnetic ratio of celestial bodies are estimated. All the
obtained values are in a satisfactory agreement with observation data.

</DOC>
<DOC>
<DOCNO> 68762 </DOCNO>
Non-extensive statistical mechanics and particle spectra in elementary


  We generalize Hagedorn's statistical theory of momentum spectra of particles
produced in high-energy collisions using Tsallis' formalism of non-extensive
statistical mechanics. Suitable non-extensive grand canonical partition
functions are introduced for both fermions and bosons. Average occupation
numbers and moments of transverse momenta are evaluated in an analytic way. We
analyse the energy dependence of the non-extensitivity parameter q as well as
the q-dependence of the Hagedorn temperature. We also take into account the
multiplicity. As a final result we obtain formulas for differential cross
sections that are in very good agreement with e+e- annihilation experiments.

</DOC>
<DOC>
<DOCNO> 152293 </DOCNO>
SUSY Breaking through CompactificationAuthors:


  We propose a new mechanism of spontaneous supersymmetry breaking. The
existence of extra dimensions with nontrivial topology plays an important role.
We investigate new features resulting from this mechanism. One noteworthy
feature is that there exists a phase in which the translational invariance for
the compactified directions is broken spontaneously. The mechanism we propose
also yields quite different vacuum structures for models with different global
symmetries.

</DOC>
<DOC>
<DOCNO> 8014 </DOCNO>
The role of Zhang-Rice singlet-like excitations in one-dimensional


  We present the first calculation of the electron-energy loss spectrum of
infinite one-dimensional undoped CuO_3 chains within a multi-band Hubbard
model. The results show good agreement with experimental spectra of Sr_2CuO_3.
The main feature in the spectra is found to be due to the formation of
Zhang-Rice singlet-like excitations. The q-dependence of these excitations is a
consequence of the inner structure of the Zhang-Rice singlet. This makes the
inclusion of the oxygen degrees of freedom essential for the description of the
relevant excitations. We observe that no enhanced intersite Coulomb repulsion
is necessary to explain the experimental data.

</DOC>
<DOC>
<DOCNO> 11362 </DOCNO>
Fluid and solid phases of the Gaussian core model


  We study the structural and thermodynamic properties of a model of point
particles interacting by means of a Gaussian pair potential first introduced by
Stillinger [Stillinger F H 1976 J. Chem. Phys. 65, 3968]. By employing integral
equation theories for the fluid state and comparing with Monte Carlo simulation
results, we establish the limits of applicability of various common closures
and examine the dependence of the correlation functions of the liquid on the
density and temperature. We employ a simple, mean-field theory for the high
density domain of the liquid and demonstrate that at infinite density the
mean-field theory is exact and that the system reduces to an `infinite density
ideal gas', where all correlations vanish and where the hypernetted chain (HNC)
closure becomes exact. By employing an Einstein model for the solid phases, we
subsequently calculate quantitatively the phase diagram of the model and find
that the system possesses two solid phases, face centered cubic and body
centered cubic, and also displays reentrant melting into a liquid at high
densities. Moreover, the system remains fluid at all densities when the
temperature exceeds 1% of the strength of the interactions.

</DOC>
<DOC>
<DOCNO> 80635 </DOCNO>
Chiral symmetry restoration and axial vector renormalization for Wilson


  Lattice gauge theories with Wilson fermions break chiral symmetry. In the
U(1) axial vector current this manifests itself in the anomaly. On the other
hand it is generally expected that the axial vector flavour mixing current is
non-anomalous. We give a short, but strict proof of this to all orders of
perturbation theory, and show that chiral symmetry restauration implies a
unique multiplicative renormalization constant for the current. This constant
is determined entirely from an irrelevant operator in the Ward identity. The
basic ingredients going into the proof are the lattice Ward identity, charge
conjugation symmetry and the power counting theorem. We compute the
renormalization constant to one loop order. It is largely independent of the
particular lattice realization of the current.

</DOC>
<DOC>
<DOCNO> 9057 </DOCNO>
Suppression and enhancement of impurity scattering in a Bose-Einstein


  Impurity atoms propagating at variable velocities through a trapped
Bose-Einstein condensate were produced using a stimulated Raman transition. The
redistribution of momentum by collisions between the impurity atoms and the
stationary condensate was observed in a time-of-flight analysis. The
collisional cross section was dramatically reduced when the velocity of the
impurities was reduced below the speed of sound of the condensate, in agreement
with the Landau criterion for superfluidity. For large numbers of impurity
atoms, we observed an enhancement of atomic collisions due to bosonic
stimulation. This enhancement is analogous to optical superradiance.

</DOC>
<DOC>
<DOCNO> 178456 </DOCNO>
Dropping Sigma-Meson Mass and In-Medium Pion-Pion Correlations


  The influence of a dropping sigma-meson mass on previously calculated
in-medium pion-pion correlations in the J=I=0 (sigma-meson) channel is
investigated. It is found that the invariant-mass distribution around the
vacuum threshold experiences a further strong enhancement over and above the
standard many-body effects. The relevance of this result for the theoretical
interpretation of this result for the theoretical interpretation of recent
A(pi-2 pi)X data is pointed out.

</DOC>
<DOC>
<DOCNO> 9649 </DOCNO>
Critical State Behaviour in a Low Dimensional Metal Induced by Strong


  We present the results of magnetotransport and magnetic torque measurements
on the alpha-(BEDT-TTF)2KHg(SCN)4 charge-transfer salt within the high magnetic
field phase, in magnetic fields extending to 33 T and temperatures as low as 27
mK. While the high magnetic field phase (at fields greater than ~ 23 T) is
expected, on theoretical grounds, to be either a modulated charge-density wave
phase or a charge/spin-density wave hybrid, the resistivity undergoes a
dramatic drop below ~ 3 K within the high magnetic field phase, falling in an
approximately exponential fashion at low temperatures, while the magnetic
torque exhibits pronounced hysteresis effects. This hysteresis, which occurs
over a broad range of fields, is both strongly temperature-dependent and has
several of the behavioural characteristics predicted by critical-state models
used to describe the pinning of vortices in type II superconductors in strong
magnetic fields. Thus, rather than exhibiting the usual behaviour expected for
a density wave ground state, both the transport and the magnetic properties of
alpha-(BEDT-TTF)2KHg(SCN)4, at high magnetic fields, closely resembles those of
a type II superconductor.

</DOC>
<DOC>
<DOCNO> 14039 </DOCNO>
Is there something of the MCT in orientationally disordered crystals ?


  Molecular Dynamics simulations have been performed on the orientationally
disordered crystal chloroadamantane: a model system where dynamics are almost
completely controlled by rotations. A critical temperature T_c = 225 K as
predicted by the Mode Coupling Theory can be clearly determined both in the
alpha and beta dynamical regimes. This investigation also shows the existence
of a second remarkable dynamical crossover at the temperature T_x > T_c
consistent with a previous NMR and MD study [1]. This allows us to confirm
clearly the existence of a 'landscape-influenced' regime occurring in the
temperature range [T_c-T_x] as recently proposed [2,3].

</DOC>
<DOC>
<DOCNO> 69208 </DOCNO>
Instanton-induced Effects in QCD High-Energy Scattering


  We evaluate a number of new instanton-induced phenomena in QCD, starting with
static dipole-dipole potentials, and proceeding to quark-quark and
dipole-dipole scattering at high energy. We use a non-perturbative formulation
of the scattering amplitude in terms of a correlator of two Wilson-lines
(quarks) or Wilson-loops (dipoles) and analyze the Euclidean amplitudes with
both perturbative gluons and instantons. The results are analytically continued
to Minkowski geometry, by interpreting the angle between the Wilson lines as
rapidity. We discuss the relevance of our results for the phenomenology of
near-forward hadronic processes at high energy, especially for processes with
multiple color exchanges.

</DOC>
<DOC>
<DOCNO> 71188 </DOCNO>
Parametrizations of Inclusive Cross Sections for Pion Production in


  Accurate knowledge of cross sections for pion production in proton-proton
collisions finds wide application in particle physics, astrophysics, cosmic ray
physics and space radiation problems, especially in situations where an
incident proton is transported through some medium, and one requires knowledge
of the output particle spectrum given the input spectrum. In such cases
accurate parametrizations of the cross sections are desired. In this paper we
review much of the experimental data and compare to a wide variety of different
cross section parametrizations. In so doing, we provide parametrizations of
neutral and charged pion cross sections which provide a very accurate
description of the experimental data. Lorentz invariant differential cross
sections, spectral distributions and total cross section parametrizations are
presented.

</DOC>
<DOC>
<DOCNO> 9752 </DOCNO>
Laplacian growth with separately controlled noise and anisotropy


  Conformal mapping models are used to study competition of noise and
anisotropy in Laplacian growth. For that, a new family of models is introduced
with the noise level and directional anisotropy controlled independently.
Fractalization is observed in both anisotropic growth and the growth with
varying noise. Fractal dimension is determined from cluster size scaling with
its area. For isotropic growth we find d = 1.7, both at high and low noise. For
anisotropic growth with reduced noise the dimension can be as low as d = 1.5
and apparently is not universal. Also, we study fluctuations of particle areas
and observe, in agreement with previous studies, that exceptionally large
particles may appear during the growth, leading to pathologically irregular
clusters. This difficulty is circumvented by using an acceptance window for
particle areas.

</DOC>
<DOC>
<DOCNO> 99559 </DOCNO>
Minimal submanifolds of Kaehler-Einstein manifolds with equal Kaehler


  We consider $F: M \to N$ a minimal oriented compact real 2n-submanifold M,
immersed into a Kaehler-Einstein manifold N of complex dimension 2n, and scalar
curvature R. We assume that $n \geq 2$ and F has equal Kaehler angles. Our main
result is to prove that, if n = 2 and $R \neq 0$, then F is either a complex
submanifold or a Lagrangian submanifold. We also prove that, if $n \geq 3$ and
F has no complex points, then: (A) If R < 0, then F is Lagrangian; (B) If R =
0, the Kaehler angle must be constant. We also study pluriminimal submanifolds
with equal Kaehler angles, and prove that, if they are not complex
submanifolds, N must be Ricci-flat and there is a natural parallel homothetic
isomorphism between TM and the normal bundle.

</DOC>
<DOC>
<DOCNO> 11631 </DOCNO>
On pinning and snapping of elastic strands


  The transient network literature up to now has considered that the connection
probability of a free strand does not depend on the strand extension, in
contrast with the disconnection probability. We argue that, on thermodynamic
grounds, both probabilities must have the same dependence on the strand
extension. We propose a model for the pinning/snapping of elastic strands
reversibly binding to sticky sites, giving explicit expressions for the
connection and disconnection rates.

</DOC>
<DOC>
<DOCNO> 10440 </DOCNO>
Knowing a network by walking on it: emergence of scaling


  A model for growing networks is introduced, having as a main ingredient that
new nodes are attached to the network through one existing node and then
explore the network through the links of the visited nodes. From exact
calculations of two limiting cases and numerical simulations the phase diagram
of the model is obtained. In the stationary limit, large network sizes, a phase
transition from a network with finite average connectivity to a network with a
power law distribution of connectivities, with no finite average, is found.
Results are compared with measurements on real networks.

</DOC>
<DOC>
<DOCNO> 68721 </DOCNO>
The CQM model


  I review a Constituent-Quark-Meson model (CQM) for heavy meson decays,
outlining its characteristics and the calculation techniques developed for it.
The strength of this effective model is that it enables to evaluate heavy meson
decay amplitudes through diagrams where the heavy mesons are attached at the
ends of loops containing heavy and light quark internal lines. The
phenomenological applications are presented in detail, trying to give a
self-contained operative picture of the model.

</DOC>
<DOC>
<DOCNO> 39943 </DOCNO>
Measurements of F2, xF3nu-xF3nub from CCFR neutrino-Fe and


  We report on the extraction of the structure functions F2 and Delta xF3 =
xF3nu-xF3nub from CCFR neutrino-Fe and antineutrino-Fe differential cross
sections. The extraction is performed in a physics model independent (PMI) way.
This first measurement for Delta xF3 which is useful in testing models of heavy
charm production, is higher than current theoretical predictions. The F2 (PMI)
values measured in neutrino and muon scattering are in good agreement with the
predictions of Next to Leading Order PDFs (using massive charm production
schemes), thus resolving the long-standing discrepancy between the two sets of
data.

</DOC>
<DOC>
<DOCNO> 152551 </DOCNO>
Toric Geometry, Enhanced non Simply laced Gauge Symmetries in


  We study the geometric engineering of supersymmetric quantum field theories
(QFT), with non simply laced gauge groups, obtained from superstring and
F-theory compactifications on local Calabi-Yau manifolds. First we review the
main lines of the toric method for ALE spaces with ADE singularities which we
extend to non simply laced ordinary and affine singularities. Then, we develop
two classes of solutions depending on the two possible realisations of the
outer-automorphism group of the toric graph $\Delta$(ADE). In F-theory on
elliptic Calabi-Yau manifolds, we give explicit results for the affine non
simply laced toric data and the corresponding BCFG mirror geometries. The
latters extend known results obtained in litterature for the affine ADE cases.
We also study the geometric engineering of $ N=1$ supersymmetric gauge theory
in eight dimensions. In type II superstring compactifications on local
Calabi-Yau threefolds, we complete the analysis for ordinary ADE singularities
by giving the explict derivation of the lacking non simply ones. Finally we
develop the basis of polyvalent toric geometry. The latter extends bivalent and
trivalent geometries, considered in the geometric engineering method, and use
it to derive a new solution for the affine $\hat D_4$ singularity. Other
features are also discussed.

</DOC>
<DOC>
<DOCNO> 13861 </DOCNO>
Numerical Replica Limit for the Density Correlation of the Random Dirac


  The zero mode wave function of a massless Dirac fermion in the presence of a
random gauge field is studied. The density correlation function is calculated
numerically and found to exhibit power law in the weak randomness with the
disorder dependent exponent. It deviates from the power law and the disorder
dependence becomes frozen in the strong randomness. A classical statistical
system is employed through the replica trick to interpret the results and the
direct evaluation of the replica limit is demonstrated numerically. The
analytic expression of the correlation function and the free energy are also
discussed with the replica symmetry breaking and the Liouville field theory.

</DOC>
<DOC>
<DOCNO> 102464 </DOCNO>
Symmetric Functions and Representations of Quantum Affine Algebras


  We study connections between the ring of symmetric functions and the
characters of irreducible finite-dimensional representations of quantum affine
algebras. We study two families of representations of the symplectic and
orthogonal Lie algebras. One is defined via combinatorial properties and is
easy to calculate; the other is closely related to the $q=1$ limit of the
``minimal affinization'' representations of quantum affine algebras. We
conjecture that the two families are identical, and present supporting evidence
and examples. In the special case of a highest weight that is a multiple of a
fundamental weight, this reduces to a conjecture of Kirillov and Reshetikhin,
recently proved by the first author.

</DOC>
<DOC>
<DOCNO> 118212 </DOCNO>
Models of Disk Evolution: Confrontation with Observations


  We present simple models for disk evolution based on two different
approaches: a forward approach based on predictions generic to hierarchical
models for structure formation (e.g., Mo, Mao, & White 1998) and a backwards
approach based on detailed modeling of the Milky Way galaxy (e.g., Bouwens,
Cayon, & Silk 1997). We normalize these models to local observations and
predict high-redshift luminosities, sizes, circular velocities, and surface
brightnesses. Both approaches yield somewhat similar predictions for size,
surface brightness, and luminosity evolution though they clearly differ in the
amount of number evolution. These predictions seem to be broadly consistent
with the high-redshift observations of Simard et al. (1999), suggesting that
the B-band surface brightness of disks has indeed evolved by ~1.5 mag from z~0
to z~1 similar to the models and is not an artifact of selection effects as
previously claimed. We also find a lack of low surface brightness galaxies in
several high redshift samples relative to model predictions based on local
samples (de Jong & van der Kruit 1994; Mathewson, Ford, & Buchhorn 1992).

</DOC>
<DOC>
<DOCNO> 100233 </DOCNO>
Three weight systems arising from intersection graphs


  We describe three weight systems arising from the intersection graphs of
chord diagrams (also known as circle graphs). These derive from the determinant
and rank of the adjacency matrix of the graph, viewed over ${\bf Z}_2$, and
from the rank of a "marked" adjacency matrix. We show that these weight systems
are exactly those given by the Conway, HOMFLYPT and Kauffman polynomials,
respectively.

</DOC>
<DOC>
<DOCNO> 8785 </DOCNO>
Optimized phonon approach for the diagonalization of electron-phonon


  We propose a new optimized phonon approach for the numerical diagonalization
of interacting electron-phonon systems combining density-matrix and Lanczos
algorithms. We demonstrate the reliablity of this approach by calculating the
phase diagram for bi-polaron formation in the one-dimensional Holstein-Hubbard
model, and the Luttinger parameters for the metallic phase of the half-filled
one-dimensional Holstein model of spinless fermions.

</DOC>
<DOC>
<DOCNO> 84328 </DOCNO>
Linear Inflation in Curvature-Quadratic Gravity


  We continue our study of gravity described by the action density
(-g)^(1/2)(R_ik^2+bR^2); and look for cosmological solutions of gravity coupled
to dust, for the closed isotropic model. There is a solution that at t
approaches zero has for the radius, a(t)=t/3^(1/2); in the absence of dust this
solution holds for all time.

</DOC>
<DOC>
<DOCNO> 8454 </DOCNO>
Structure and Magnetism of well-defined cobalt nanoparticles embedded in


  Our recent studies on Co-clusters embedded in various matrices reveal that
the co-deposition technique (simultaneous deposition of two beams : one for the
pre-formed clusters and one for the matrix atoms) is a powerful tool to prepare
magnetic nanostructures with any couple of materials even though they are
miscible. We study, both sharply related, structure and magnetism of the Co/Nb
system. Because such a heterogeneous system needs to be described at different
scales, we used microscopic and macroscopic techniques but also local selective
absorption ones. We conclude that our clusters are 3 nm diameter f.c.c
truncated octahedrons with a pure cobalt core and a solid solution between Co
and Nb located at the interface which could be responsible for the magnetically
inactive monolayers we found. The use of a very diluted Co/Nb film, further
lithographed, would allow us to achieve a pattern of microsquid devices in view
to study the magnetic dynamics of a single-Co cluster.

</DOC>
<DOC>
<DOCNO> 121546 </DOCNO>
High Spatial Resolution Imaging of NGC 1068 in the Mid Infrared


  Mid-infrared observations of the central source of NGC 1068 have been
obtained with a spatial resolution in the deconvolved image of 0.1" (~ 7pc).
The central source is extended by ~1" in the north-south direction but appears
unresolved in the east-west direction over most of its length. About two-thirds
of its flux can be ascribed to a core structure which is itself elongated
north-south and does not show a distinct unresolved compact source. The source
is strongly asymmetric, extending significantly further to the north than to
the south. The morphology of the mid-infrared emission appears similar to that
of the radio jet, and has features which correlate with the images in [O III].
Its 12.5-24.5 micron color temperature ranges from 215 to 260 K and does not
decrease smoothly with distance from the core. Silicate absorption is strongest
in the core and to the south and is small in the north.
  The core, apparently containing two-thirds of the bolometric luminosity of
the inner 4" diameter area, may be explained by a thick, dusty torus near the
central AGN viewed at an angle of ~65 deg to its plane. There are, however,
detailed difficulties with existing models, especially the narrow east-west
width of the thin extended mid-infrared "tongue" to the north of the core. We
interpret the tongue as re-processed visual and ultraviolet radiation that is
strongly beamed and that originates in the AGN.

</DOC>
<DOC>
<DOCNO> 150800 </DOCNO>
Target Space Duality I: General Theory


  We develop a systematic framework for studying target space duality at the
classical level. We show that target space duality between manifolds M and
Mtilde arises because of the existence of a very special symplectic manifold.
This manifold locally looks like M x Mtilde and admits a double fibration. We
analyze the local geometric requirements necessary for target space duality and
prove that both manifolds must admit flat orthogonal connections. We show how
abelian duality, nonabelian duality and Poisson-Lie duality are all special
cases of a more general framework. As an example we exhibit new (nonlinear)
dualities in the case M = Mtilde = R^n.

</DOC>
<DOC>
<DOCNO> 117508 </DOCNO>
On energy-dependent propagation effects and acceleration sites of


  We consider the effect of energy dependent propagation of relativistic
electrons in a spatially inhomogeneous medium in order to interpret the
broad-band nonthermal radiation of the young supernova remnant (SNR) Cassiopeia
A. A two-zone model is proposed that distinguishes between compact, bright
steep-spectrum radio knots and the bright fragmented radio ring on the one
hand, and the remainder of the shell - the diffuse `plateau' - on the other
hand. In the framework of this model it is possible to explain the basic
features of the spectral and temporal evolution of the synchrotron radiation of
Cas A if one assumes that these compact structures correspond to sites of
efficient electron acceleration producing hard spectra of accelerated particles
with power-law indices ~2.2. The resulting energy distribution of radio
electrons in these compact structures becomes significantly steeper than the
electron production spectrum on timescales of the energy dependent escape of
these electrons into the surrounding diffuse plateau region. We argue that the
steepness, rather than the hardness, of the radio spectra of compact bright
structures in clumpy sources can in general be considered as a typical
signature of sites where strong electron acceleration has built up high
gradients in the spatial distribution of radio electrons. Subsequent diffusive
escape then modifies their energy distribution, leading to spatial variations
of spectral indices within the radio source. Qualitative and quantitative
interpretations of a number of observational data of Cas A are given.
Predictions following from the model are discussed.

</DOC>
<DOC>
<DOCNO> 119911 </DOCNO>
Neutrinos in physics, astrophysics, and cosmology


  A brief review of neutrino anomalies in particle physics and of the role
played by neutrinos in cosmology and astrophysics is presented. The main part
of the talk is dedicated to the impact of neutrinos and in particular of
neutrino oscillations on BBN and to a possible spatial variation of primordial
abundances.

</DOC>
<DOC>
<DOCNO> 13726 </DOCNO>
Interatomic collisions in a tightly confined Bose gas


  We discuss pair interatomic collisions in a Bose gas tightly confined in one
(axial) direction and identify two regimes of scattering. In the quasi2D
regime, where the confinement frequency $\omega_0$ greatly exceeds the gas
temperature $T$, the scattering rates exhibit 2D features of the particle
motion. At temperatures $T\sim\hbar\omega_0$ one has a confinement-dominated 3D
regime, where the confinement can change the momentum dependence of the
scattering amplitudes. We describe the collision-induced energy exchange
between the axial and radial degrees of freedom and analyze recent experiments
on thermalization and spin relaxation rates in a tightly (axially) confined gas
of Cs atoms.

</DOC>
<DOC>
<DOCNO> 169845 </DOCNO>
Disagreement between correlations of quantum mechanics and stochastic


  Intracavity and external third order correlations in the damped nondegenerate
parametric oscillator are calculated for quantum mechanics and stochastic
electrodynamics (SED), a semiclassical theory. The two theories yield greatly
different results, with the correlations of quantum mechanics being cubic in
the system's nonlinear coupling constant and those of SED being linear in the
same constant. In particular, differences between the two theories are present
in at least a mesoscopic regime. They also exist when realistic damping is
included. Such differences illustrate distinctions between quantum mechanics
and a hidden variable theory for continuous variables.

</DOC>
<DOC>
<DOCNO> 83164 </DOCNO>
The (Lazy) Functional Side of Logic Programming


  The possibility of translating logic programs into functional ones has long
been a subject of investigation. Common to the many approaches is that the
original logic program, in order to be translated, needs to be well-moded and
this has led to the common understanding that these programs can be considered
to be the ``functional part'' of logic programs. As a consequence of this it
has become widely accepted that ``complex'' logical variables, the possibility
of a dynamic selection rule, and general properties of non-well-moded programs
are exclusive features of logic programs. This is not quite true, as some of
these features are naturally found in lazy functional languages. We readdress
the old question of what features are exclusive to the logic programming
paradigm by defining a simple translation applicable to a wider range of logic
programs, and demonstrate that the current circumscription is unreasonably
restrictive.

</DOC>
<DOC>
<DOCNO> 121748 </DOCNO>
Properties of Simulated Magnetized Galaxy Clusters


  We study the evolution of magnetized clusters in a cosmological environment
using magneto-hydro dynamical simulations. Large scale flows and merging of
subclumps generate shear flows leading to Kelvin-Helmholtz instabilities,
which, in addition to the compression of the gas where the magnetic field is
frozen in, further amplify the magnetic field during the evolution of the
cluster. Therefore, well-motivated initial magnetic fields of
$<B^2>^{1/2}=10^{-9} {\rm G}$ reach the observed $\sim\mu{\rm G}$ field
strengths in the cluster cores at $z=0$. These magnetized clusters can be used
to study the final magnetic field structure, the dynamical importance of
magnetic fields for the interpretation of observed X-Ray properties, and help
to constrain further processes in galaxy clusters like the population of
relativistic particles giving rise to the observed radio halos or the behavior
of magnetized cooling flows.

</DOC>
<DOC>
<DOCNO> 151740 </DOCNO>
Magnetic Symmetries and Vortices In Chern-Simons Theories


  We study the locality properties of the vortex operators in compact U(1)
Maxwell-Chern-Simons and SU(N) Yang-Mills-Chern-Simons theories in 2+1
dimensions. We find that these theories do admit local vortex operators and
thus in the UV regularized versions should contain stable magnetic vortices. In
the continuum limit however the energy of these vortex excitations generically
is logarithmically UV divergent. Nevertheless the classical analysis shows that
at small values of CS coefficient $\kappa$ the vortices become light. It is
conceivable that they in fact become massless and condense due to quantum
effects below some small $\kappa$. If this happens the magnetic symmetry breaks
spontaneously and the theory is confining.

</DOC>
<DOC>
<DOCNO> 121293 </DOCNO>
The cosmic gamma-ray background in the MeV range


  The $\gamma$-ray background from supernovae is calculated on the basis of the
reconstructed efficiency of supernova explosions from star formation at various
redshifts. The calculations presented here show how Type Ia SN rates compatible
with the results of optical supernova searches give a background emission in
the MeV range that can explain the extragalactic emission measured by COMPTEL
and SMM. Star formation histories reaching maximum values of 0.3-0.4
M$_{\odot}$ yr$^{-1}$ Mpc$^{-3}$ at z$\sim$ 1.5 (and/or possibly keeping that
value to higher z) give a $\gamma$-ray background compatible with observations
while they also predict the observed supernova rates per comoving volume. The
$\gamma$-ray background in the MeV range is mostly sensitive to the star
formation rate at z$\sim$ 1-2, but the activity in forming stars at even higher
z has an influence as well on the absolute level of the cosmic $\gamma$-ray
background: the time elapsed by the SNe Ia progenitors until they explode has a
broad distribution and the rates of SNe Ia at z$\sim$ 1.5-2 depend on the
formation frequencies of their progenitor stars at earlier epochs.
  The mutual consistency of predictions of optical rates and integrated
emission in the $\gamma$-ray domain place in a firm ground the Type Ia
supernova identification as the astrophysical source responsible for this
cosmic background

</DOC>
<DOC>
<DOCNO> 71507 </DOCNO>
Brane Fluctuation and New Counting Rules for Kaluza-Klein Towers


  In models with extra dimensions, branes have been usually treated as solid
bodies though they are prohibited by the relativity. In the previous letter, we
proposed a method of taking account of brane fluctuation by introducing
Nambu-Goldstone bosons, and prove that when a tension of the brane is small,
the interaction between boundary fields and Kaluza-Klein modes is suppressed
exponentially. In this letter, we further investigate this suppression in more
generic configuration, and obtain three counting rules, ``AND'', ``OR'' and
``STACK'' rules, depending on the softness of branes and the character of
fields on the branes four dimensions. The choice determines the number of
Kaluza-Klein towers contributing to renormalization group equations, leading to
a remarkable change in the running behavior of coupling constants.

</DOC>
<DOC>
<DOCNO> 14028 </DOCNO>
Collisionless collective modes of fermions in magnetic traps


  We present a Random-Phase-Approximation formalism for the collective spectrum
of two hyperfine species of dilute 40K atoms, magnetically trapped at zero
temperature and subjected to a repulsive s-wave interaction between atoms with
different spin projections. We examine the density-like and the spin-like
oscillation spectra, as well as the transition density profiles created by
external multipolar fields. The zero sound spectrum is always fragmented and
the density and spin channels become clearly distinguishable if the trapping
potentials acting on the species are identical. Although this distinction is
lost when these confining fields are different, at selected excitation
frequencies the transition densities may display the signature of the channel.

</DOC>
<DOC>
<DOCNO> 120675 </DOCNO>
The Narrow-Line Region of Seyfert Galaxies: Narrow-Line Seyfert 1


  It is known that the spectral energy distribution (SED) of the nuclear
radiation of narrow-line Seyfert 1 galaxies (NLS1s) has different shapes with
respect to that of ordinary broad-line Seyfert 1 galaxies (BLS1s), particularly
in wavelengths of X-ray. This may cause some differences in the ionization
degree and the temperature of gas in narrow-line regions (NLRs) between NLS1s
and BLS1s. This paper aims to examine whether or not there are such differences
in the physical conditions of NLR gas between them. For this purpose, we have
compiled the emission-line ratios of 36 NLS1s and 83 BLS1s from the literature.
Comparing these two samples, we have found that the line ratios of [O {\sc
i}]$\lambda$6300/[O {\sc iii}]$\lambda$5007 and [O {\sc iii}]$\lambda$4363/[O
{\sc iii}]$\lambda$5007, which represent the ionization degree and the gas
temperature respectively, are statistically indistinguishable between NLS1s and
BLS1s. Based on new photoionization model calculations, we show that these
results are not inconsistent with the difference of the SED between them. The
influence of the difference of SEDs on the highly ionized emission lines is
also briefly discussed.

</DOC>
<DOC>
<DOCNO> 8058 </DOCNO>
Metal-Kondo insulating transitions and transport in one dimension


  We study two different metal-insulating transitions possibly occurring in
one-dimensional Kondo lattices. First, we show how doping the pure Kondo
lattice model in the strong-coupling limit, results in a Pokrovsky-Talapov
transition. This produces a conducting state with a charge susceptibility
diverging as the inverse of the doping, that seems in agreement with numerical
datas. Second, in the weak-coupling region, Kondo insulating transitions arise
due to the consequent renormalization of the backward Kondo scattering. Here,
the interplay between Kondo effect and electron-electron interactions gives
rise to significant phenomena in transport, in the high-temperature delocalized
(ballistic) regime. For repulsive interactions, as a perfect signature of Kondo
localization, the conductivity is found to decrease monotonically with
temperature. When interactions become attractive, spin fluctuations in the
electron (Luttinger-type) liquid are suddenly lowered. The latter is less
localized by magnetic impurities than for the repulsive counterpart, and as a
result a large jump in the Drude weight and a maximum in the conductivity arise
in the entrance of the Kondo insulating phase. These can be viewed as remnants
of s-wave superconductivity arising for attractive enough interactions.
Comparisons with transport in the single impurity model are also performed. We
finally discuss the case of randomly distributed magnetic defects, and the
applications on persistent currents of mesoscopic rings.

</DOC>
<DOC>
<DOCNO> 117934 </DOCNO>
Breaking the degeneracy of cosmological parameters in galaxy redshift


  The measurement of cosmological parameters is investigated in a
representation of the least-action method that uses a redshift-space dataset to
simultaneously constrain the real-space fields $\delta$,$\b v$. This method is
robust in recovering the entire evolution of the matter density contrast and
peculiar velocities of galaxies in real space from current galaxy redshift
surveys. The main strength of the method is that it permits us to break the
degeneracy of the parameters $b$ and $\Omegam$ (customarily measured in the
ratio $\beta\equiv \Omegam^{0.6}/b$ from redshift-space distortions), and these
are evaluated in the current context separately. The procedure provides a
simple numerical means to extract as much information as possible from a given
sample, in the simplest linear bias model, before resorting to cosmic
complementarity to resolve the degeneracy in the measurement of $\Omegam$. The
same premise applies to more sophisticated choices of bias models. We construct
a likelihood parameter $\lambda(b,\Omegam)$ to evaluate the relative likelihood
of different values of $b$ and $\Omegam$. The method is applied to the \iras
redshift survey with a low-resolution Gaussian smoothing length of 1200 \km
within a spherical region $x_{\rm max} \sim 15,000$ \km and the reconstructed
velocity field is then compared with POTENT-reconstructed velocities from the
Mark III radial-velocity dataset within a radius $\sim 5000$ \km, which have
been suitably prepared to account for Malmquist bias and other systematic
errors. The analysis yields a likelihood for the parameters that is overall
consistent with $\Omegam\approx 0.3$ and $b\approx 1.1$, thus lending support
to a non-vanishing cosmological constant $\Omega_{\Lambda}\approx 0.7$ in a
flat universe.

</DOC>
<DOC>
<DOCNO> 11558 </DOCNO>
Comment on ``Confinement of slave particles in U(1) gauge theories of


  In a recent Letter, Nayak argued that slave partices are always confined in
gauge theories of strongly-correlated electron systems like the t-J model. The
argument mostly relies on Elitzur's theorem and the fact that the effective
gauge theory under discussion is at infinite coupling. On the other hand, in
the previous papers we studied dynamics of the gauge theory of the t-J model
showing that the slave particles are in the Coulomb phase below certain
critical temperature T{CSS} that depends on hole doping. We comment on the
discrepancy between the results in two papers.

</DOC>
<DOC>
<DOCNO> 152577 </DOCNO>
High Energy Behavior of Wilson Lines


  We investigate the high energy behavior of the correlation functions of the
open Wilson lines in noncommutative gauge theory. We obtain a very simple
physical picture that they are bound to form a group of closed Wilson loops. We
prove our claim in the weak coupling region by perturbative analysis. We
emphasize the importance of respecting the cyclic symmetry of the straight
Wilson lines to compute the correlation functions. The implications for stringy
calculation of the correlators are also discussed.

</DOC>
<DOC>
<DOCNO> 12222 </DOCNO>
Heat kernel regularization of the effective action for stochastic


  The presence of fluctuations and non-linear interactions can lead to scale
dependence in the parameters appearing in stochastic differential equations.
Stochastic dynamics can be formulated in terms of functional integrals. In this
paper we apply the heat kernel method to study the short distance
renormalizability of a stochastic (polynomial) reaction-diffusion equation with
real additive noise. We calculate the one-loop {\emph{effective action}} and
its ultraviolet scale dependent divergences. We show that for white noise a
polynomial reaction-diffusion equation is one-loop {\emph{finite}} in $d=0$ and
$d=1$, and is one-loop renormalizable in $d=2$ and $d=3$ space dimensions. We
obtain the one-loop renormalization group equations and find they run with
scale only in $d=2$.

</DOC>
<DOC>
<DOCNO> 122921 </DOCNO>
Lost and Found: The Damped Lyman Alpha Absorbers in the QSO OI 363


  The galaxy giving rise to the damped Ly$\alpha$ absorbing system in the QSO
OI 363 with z=0.221 has been found. A galaxy which is probably associated with
the second DLA in this same QSO at z=0.0912 has also been found. Neither galaxy
is very luminous, and neither galaxy shows signs of extensive current star
formation, a massive disk or lots of gas. The impact parameters for each of the
two galaxies with respect to the QSO are reasonable. If most DLA absorbers
arise in such low luminosity galaxies, it will be difficult to pick out the
correct galaxy giving rise to DLA systems at high redshift within the large
projected areal density on the sky of faint galaxies around distant QSOs.

</DOC>
<DOC>
<DOCNO> 72212 </DOCNO>
On the group velocity of oscillating neutrino states and the equal


  In a two flavour world, the usual equal $p$, equal $E$, or equal $v$
assumptions used to derive the neutrino oscillation length can be replaced by a
specific definition of the velocity of the oscillating state which, unlike
those assumptions, is compatible with exact production kinematics. This
definition is further vindicated by the analysis of $\pi_{\mu 2}$ decay at
rest.

</DOC>
<DOC>
<DOCNO> 67737 </DOCNO>
Constraints on the Gluon Density from Lepton Pair Production


  The hadroproduction of lepton pairs with mass Q and finite transverse
momentum Q_T is described in perturbative QCD by the same partonic subprocesses
as prompt photon production. We demonstrate that, like prompt photon
production, lepton pair production is dominated by quark-gluon scattering in
the region Q_T>Q/2. This feature leads to sensitivity to the gluon density in
kinematical regimes accessible in collider and fixed target experiments, and it
provides a new independent method for constraining the gluon density.

</DOC>
<DOC>
<DOCNO> 170021 </DOCNO>
Improved Precision Measurement of the Casimir Force Using Gold Surfaces


  We report an improved precision measurement of the Casimir force using
metallic gold surfaces. The force is measured between a large gold coated
sphere and flat plate using an Atomic Force Microscope. The use of gold
surfaces removes some theoretical uncertainties in the interpretation of the
measurement. The forces are also measured at smaller surface separations. The
complete dielectric spectrum of the metal is used in the comparison of theory
to the experiment. The average statistical precision remains at the same 1% of
the forces measured at the closest separation. These results should lead to the
development of stronger constraints on hypothetical forces.

</DOC>
<DOC>
<DOCNO> 69429 </DOCNO>
Chiral Models of Weak Scale Supersymmetry


  I discuss supersymmetric extensions of the Standard Model containing an extra
U(1)' gauge symmetry which provide a solution to the mu-problem and at the same
time protect the proton from decaying via dimension 4 operators. Moreover, all
fields are protected by chirality and supersymmetry from acquiring high scale
masses. The additional requirements of anomaly cancellation and gauge coupling
unification imply the existence of extra matter multiplets and that several
fields participate in U(1)' symmetry breaking simultaneously. While there are
several studies addressing subsets of these requirements, this work uncovers
simultaneous solutions to all of them. It is surprising and encouraging that
extending the Minimal Supersymmetric Standard Model by a simple U(1) factor
solves its major drawbacks with respect to the non-supersymmetric Standard
Model, especially as current precision data seem to offer a hint to the
existence of its corresponding Z' boson. It is also remarkable that there are
many solutions where the U(1)' charges of the known quarks and leptons are
predicted to be identical to those E_6 motivated Z' bosons which give the best
fit to the data. I discuss the solutions to these constraints including some
phenomenological implications.

</DOC>
<DOC>
<DOCNO> 83115 </DOCNO>
Relevance Sensitive Non-Monotonic Inference on Belief Sequences


  We present a method for relevance sensitive non-monotonic inference from
belief sequences which incorporates insights pertaining to prioritized
inference and relevance sensitive, inconsistency tolerant belief revision.
 Our model uses a finite, logically open sequence of propositional formulas as
a representation for beliefs and defines a notion of inference from
maxiconsistent subsets of formulas guided by two orderings: a temporal
sequencing and an ordering based on relevance relations between the conclusion
and formulas in the sequence. The relevance relations are ternary (using
context as a parameter) as opposed to standard binary axiomatizations. The
inference operation thus defined easily handles iterated revision by
maintaining a revision history, blocks the derivation of inconsistent answers
from a possibly inconsistent sequence and maintains the distinction between
explicit and implicit beliefs. In doing so, it provides a finitely presented
formalism and a plausible model of reasoning for automated agents.

</DOC>
<DOC>
<DOCNO> 85053 </DOCNO>
A Note in Cosmology and Loop Quantum Gravity


  One possible description of the very early stages of the evolution of the
universe is provided by Chaotic Inflationary Cosmology. For that model the role
of the inflaton field is played by quantum gravitational effects. We study if
such a picture may arise within the framework of Loop Quantum gravity by
studying a simple model. While we were unable to reach definitive conclusions
we believe the general approach proposed in this paper may prove fruitful in
the future.

</DOC>
<DOC>
<DOCNO> 118787 </DOCNO>
Direct Detection of Nonbaryonic Dark Matter


  Weakly Interacting Massive Particles (WIMPs) are leading candidates for the
dominant part of the mass density of the Universe. Here we will review direct
WIMP detection techniques by giving examples of currently running experiments,
and present the status of the most promising future projects.

</DOC>
<DOC>
<DOCNO> 102278 </DOCNO>
A one-dimensional embedding complex


  We give the first explicit computations of rational homotopy groups of spaces
of "long knots" in Euclidean spaces. We define a spectral sequence which
converges to these rational homotopy groups whose E^1 term is defined in terms
of braid Lie algebras. For odd k we establish a vanishing line for this
spectral sequence, show the Euler characteristic of the rows of this E^1 term
is zero, and make calculations of E^2 in a finite range.

</DOC>
<DOC>
<DOCNO> 7841 </DOCNO>
Octupole Moment as a Hidden Order Parameter in Orbitally Degenerate


  Possibility of a novel pseudo-scalar (octupole) order is studied
theoretically for orbitally degenerate systems with strong spin-orbit coupling
such as Ce$_x$La$_{1-x}$B$_6$. It is discussed that coexistence of an octupole
order parameter and antiferromagnetic fluctuation should lead to drastic
softening of the elastic constant by a mode-mixing effect. Nonlinear coupling
between dipole, quadrupole and octupole fluctuations is taken into account in
terms of a Ginzburg-Landau-type functional which is derived microscopically
through path integral.

</DOC>
<DOC>
<DOCNO> 40270 </DOCNO>
Tau Neutrinos Favored over Sterile Neutrinos in Atmospheric Muon


  The previously published atmospheric neutrino data did not distinguish
whether muon neutrinos were oscillating into tau neutrinos or sterile
neutrinos, as both hypotheses fit the data. Using data recorded in 1100
live-days of the Super-Kamiokande detector, we use three complementary data
samples to study the difference in zenith angle distribution due to neutral
currents and matter effects. We find no evidence favoring sterile neutrinos,
and reject the hypothesis at the 99% confidence level. On the other hand, we
find that oscillation between muon and tau neutrinos suffices to explain all
the results in hand.

</DOC>
<DOC>
<DOCNO> 170395 </DOCNO>
What does an observed quantum system reveal to its observer ?


  The evolution of a quantum system under observation becomes retarded or even
impeded. We review this ``quantum Zeno effect'' in the light of the criticism
that has been raised upon a previous attempt to demonstrate it, of later
reexaminations of both the projection postulate and the significance of the
observations, and of the results of a recent experiment on an individual cold
atom. Here, the micro-state of the quantum system gets unveiled with the
observation, and the effect of measurement is no longer mixed up with dephasing
the object's wave function by the reactive effect of the detection. A procedure
is outlined that promises to provide, by observation, an upper limit for the
delay of even an exponential decay.

</DOC>
<DOC>
<DOCNO> 9753 </DOCNO>
Evidence of Electron Fractionalization from Photoemission Spectra in the


  In the normal state of the high temperature superconductors
Bi_2Sr_2CaCu_2O_{8+delta} and La_{2-x}Sr_{x}CuO_4, and in the related ``stripe
ordered'' material La_1.25Nd_0.6Sr_0.15CuO_4, there is sharp structure in the
measured single hole spectral function A(k,w) considered as a function of k at
fixed small binding energy w. At the same time, as a function of w at fixed k
on much of the putative Fermi surface, any structure in A(k,w), other than the
Fermi cutoff, is very broad. This is characteristic of the situation in which
there are no stable excitations with the quantum numbers of the electron, as is
the case in the one dimensional electron gas.

</DOC>
<DOC>
<DOCNO> 121583 </DOCNO>
Parsec-scale structures of radio galaxies in the 2-Jy sample


  In this paper we present the results of VLBI observations of six radio
galaxies belonging to the 2-Jy sample. The selected objects are 3C17, PKS
0620-52, PKS 0625-35, PKS 1318-43, PKS 1333-33 and 3C317. The first is a high
power radio galaxy and the remainder are low power objects. Our observations
were carried out with a set of different arrays and frequencies, and cover a
range of resolutions from a few mas to a few tens of mas. Parsec-scale images
are presented and discussed in the light of unification for radio loud
galaxies. Estimates for the intrinsic plasma speed in these objects in the
proximity of the parsec-scale core and tehir orientation to the line of sight
are in agreement with the predictions from unified models and their optical and
X-ray properties.

</DOC>
<DOC>
<DOCNO> 99274 </DOCNO>
Some Generalized Kac-Moody Algebras With Known Root Multiplicities


  Starting from Borcherds' fake monster Lie algebra we construct a sequence of
six generalized Kac-Moody algebras whose denominator formulas, root systems and
all root multiplicities can be described explicitly. The root systems decompose
space into convex holes, of finite and affine type, similar to the situation in
the case of the Leech lattice. As a corollary, we obtain strong upper bounds
for the root multiplicities of a number of hyperbolic Lie algebras, including
AE3.

</DOC>
<DOC>
<DOCNO> 12568 </DOCNO>
Fluctuation Effects in High Sheet Resistance Superconducting Films


  As the normal state sheet resistance, $R_n$, of a thin film superconductor
increases, its superconducting properties degrade. For $R_n\simeq h/4e^2$
superconductivity disappears and a transition to a nonsuperconducting state
occurs. We present electron tunneling and transport measurements on ultrathin,
homogeneously disordered superconducting films in the vicinity of this
transition. The data provide strong evidence that fluctuations in the amplitude
of the superconducting order parameter dominate the tunneling density of states
and the resistive transitions in this regime. We briefly discuss possible
sources of these amplitude fluctuation effects. We also describe how the data
suggest a novel picture of the superconductor to nonsuperconductor transition
in homogeneous 2D systems.

</DOC>
<DOC>
<DOCNO> 12723 </DOCNO>
Magnetostriction and magnetoelastic domains in antiferromagnets


  The problem of the observable equilibrium domain structure in pure
antiferromagnets (and other thermoelastics) is investigated with the use of
continuous elasticity theory. It is shown that completely rigid surface
produces the imaginary ``incompatibility elastic charges'' analogous to the
surface magnetic charges in ferromagnets. Corresponding long-range field is
shown to contribute into the ``stray'' energy of the sample that governs an
appearance of the domain structure, the contribution from the ``elastic
charges'' being proportional to the sample volume. Competition between the
elastic ``stray'' field that favors inhomogeneous strain distribution, and
external field that tends to homogenize the sample, provides the reversible
reconstruction of the domain structure under the action of external magnetic
field.

</DOC>
<DOC>
<DOCNO> 102885 </DOCNO>
Classification of (n-5)-filiform Lie algebras


  In this paper we consider the problem of classifying the $(n-5)$-filiform Lie
algebras. This is the first index for which infinite parametrized families
appear, as can be seen in dimension $7.$ Moreover we obtain large families of
characteristic nilpotent Lie algebras with nilpotence index 5 and show that at
least for dimension 10 there is a characteristic nilpotent Lie algebra with
nilpotence index 4 which is the algebra of derivations of a nilpotent Lie
algebra.

</DOC>
<DOC>
<DOCNO> 178704 </DOCNO>
Dynamical calculation of $d^*$ mass and NN decay width in the quark


  The mass estimate of the $d^* (IJ^P=03^+)$ dibaryon is improved by a
dynamical calculation in the quark delocalization, color screening model. The
partial decay width of $d^*$ into an $NN$ D-wave state is also obtained. The
mass obtained is slightly larger than that obtained in adiabatic calculations,
due to the anharmonicity of the effective potential between two $\Delta$'s. The
value of the width obtained due to tensor one-gluon-exchange is about 5 MeV,
comparable in magnitude to earlier results found using pion exchange.

</DOC>
<DOC>
<DOCNO> 70858 </DOCNO>
Top quark total and differential cross sections at NNLO and NNLL


  I present recent NNLO-NNLL results for top quark hadroproduction at the
Tevatron. The total cross section as well as transverse momentum and rapidity
distributions are shown.

</DOC>
<DOC>
<DOCNO> 69534 </DOCNO>
U(1) symmetry and R parity violation


  The patterns of $R$ violation resulting from imposition of a gauged U(1)
horizontal symmetry on the minimal supersymmetric standard model are
systematically analyzed. We concentrate on class of models with integer U(1)
charges chosen to reproduce the quark masses and mixings as well as charged
lepton masses exactly or approximately. The U(1) charges are further restricted
by the requirement that very large bilinear lepton number violating terms
should not be allowed in the superpotential. It is shown that this leads to
severely constrained patterns of trilinear interactions. Specifically, only
choice compatible with phenomenological restrictions is the one in which all
the trilinear $\lambda'_{ijk}$ and all but at most two trilinear
$\lambda_{ijk}$ couplings vanish or are enormously suppressed. The U(1)
symmetry can allow effective generation of bilinear lepton number violating
parameters through terms in the Kahler potential. Resulting models are
identified and structure of neutrino masses in some of these is briefly
discussed.

</DOC>
<DOC>
<DOCNO> 174444 </DOCNO>
Spectroscopy of 13,14B via the one-neutron knockout reaction


  The single-nucleon knockout reactions 9Be(14B, 13B + gamma)X and 197Au(14B,
13B + gamma)X, at an incident energy of 60 MeV per nucleon, have been used to
probe the structure of 14B and of the core fragment 13B. A dominant 2s
configuration is deduced for the neutron in the ground state of 14B. The
longitudinal momentum distribution for this state is consistent with "neutron
halo" structure. Spin assignments for 13B excited states at 3.48 and 3.68 MeV
are proposed based on the observed spectroscopic factors for one-neutron
removal.

</DOC>
<DOC>
<DOCNO> 11474 </DOCNO>
An elastic model for the In-In correlations in In(x)Ga(1-x)As


  Deviations from randomicity in In(x)Ga(1-x) As semiconductor alloys induced
by elastic effects are investigated within the Keating potential. Our model is
based on Monte Carlo simulations on large (4096 atoms) supercells, performed
with two types of boundary conditions: Fully periodic boundary conditions
represent the bulk, while periodic boundary conditions along the x and y
directions and a free surface in the z direction simulate the epitaxial growth
environment. We show that In-In correlations identified in the bulk tend to be
enhanced in the epitaxially grown samples.

</DOC>
<DOC>
<DOCNO> 122117 </DOCNO>
A Young Stellar Cluster in the Nucleus of NGC 4449


  We have obtained 1-2 A resolution optical Echellette spectra of the nuclear
star cluster in the nearby starburst galaxy NGC 4449. The light is clearly
dominated by a very young (6-10 Myr) population of stars. For our age dating,
we have used recent population synthesis models to interpret the observed
equivalent width of stellar absorption features such as the HI Balmer series
and the CaII triplet around 8500 A. We also compare the observed spectrum of
the nuclear cluster to synthesized spectra of simple stellar populations of
varying ages. All these approaches yield a consistent cluster age. Metallicity
estimates based on the relative intensities of various ionization lines yield
no evidence for significant enrichment in the center of this low mass galaxy:
the metallicity of the nuclear cluster is about one fourth of the solar value,
in agreement with independent estimates for the disk material of NGC 4449.

</DOC>
<DOC>
<DOCNO> 118041 </DOCNO>
Precise Measurement of Cosmic-Ray Proton and Helium Spectra with the


  We report cosmic-ray proton and helium spectra in energy ranges of 1 to 120
GeV and 1 to 54 GeV/nucleon, respectively, measured by a balloon flight of the
BESS spectrometer in 1998. The magnetic-rigidity of the cosmic-rays was
reliably determined by highly precise measurement of the circular track in a
uniform solenoidal magnetic field of 1 Tesla. Those spectra were determined
within overall uncertainties of +-5 % for protons and +- 10 % for helium nuclei
including statistical and systematic errors.

</DOC>
<DOC>
<DOCNO> 67684 </DOCNO>
Are Kaluza-Klein modes enhanced by parametric resonance?


  We study parametric amplification of Kaluza-Klein (KK) modes in a higher
$D$-dimensional generalized Kaluza-Klein theory, which was originally
considered by Mukohyama in the narrow resonance case. It was suggested that KK
modes can be enhanced by an oscillation of a scale of compactification by the
$d$-dimensional sphere $S^d~(d=D-4)$ and by the direct product $S^{d_1}\times
S^{d_2}~(d_1+d_2=D-4)$. We extend this past work to the more general case where
initial values of the scale of compactification and the quantum number of the
angular momentum $l$ of KK modes are not small. We perform analytic approaches
based on the Mathieu equation as well as numerical calculations, and find that
the expansion of the universe rapidly makes the KK field deviate from
instability bands. As a result, KK modes are not enhanced sufficiently in an
expanding universe in these two classes of models.

</DOC>
<DOC>
<DOCNO> 169873 </DOCNO>
A genuine reinterpretation of the Heisenberg's ("uncertainty") relations


  In spite \smallskip of their popularity the \QTR{bf}{H}eisenberg's
(``uncertainty'') \QTR{bf}{R}elations (HR) still generate controversies. The
\QTR{bf}{T}raditional \QTR{bf}{I}nterpretation of HR (TIHR) dominate our days
science, although over the years a lot of its defects were signaled. These
facts justify a reinvestigation of the questions connected with the
interpretation / significance of HR. Here it is developped such a
reinvestigation starting with a revaluation of the main elements of TIHR. So
one finds that all the respective elements are troubled by insurmountable
defects. Then it results the indubitable failure of TIHR and the necessity of
its abandonment. Consequently the HR must be deprived of their quality of
crucial physical formulae. Moreover the HR are shown to be nothing but simple
fluctuations formulae with natural analogous in classical (non-quantum)
physics. The description of the maesuring uncertainties (traditionally
associated with HR) is approached from a new informational perspective. The
Planck's constant $\hbar $ (also associated with HR) is revealed to have a
significance of generic indicator for quantum stochasticity, similarly with the
role of Boltzmann's constant k in respect with the thermal stochasticity.

</DOC>
<DOC>
<DOCNO> 120017 </DOCNO>
SNIa data to probe the Cosmological Principle


  Recently collected SNIa data have been used to address the problem of
measuring the cosmological parameters of the universe. Analysed in the
framework of homogeneous models, they have yielded, as a primary result, a
strictly positive cosmological constant. However, a straight reading of the
published measurements, conducted with no a priori idea of which model would
best describe our universe, at least up to redshifts z=1, does not exclude the
possibility of ruling out the Cosmological Principle - and cosmological
constant - hypotheses. It is here shown how the large scale (in)homogeneity of
this part of the universe can be tested on our past light cone, using the
magnitude-redshift relation, provided sufficiently accurate data from sources
at redshifts approaching z=1 would be available.

</DOC>
<DOC>
<DOCNO> 99732 </DOCNO>
N-graphs, modular Sidon and sum-free sets, and partition identities


  Using a new graphical representation for partitions, the author obtains a
family of partition identities associated with partitions into distinct parts
of an arithmetic progression, or, more generally, with partitions into distinct
parts of a set that is a finite union of arithmetic progressions associated
with a modular sum-free Sidon set. Partition identities are also constructed
for sets associated with modular sum-free sets.

</DOC>
<DOC>
<DOCNO> 9489 </DOCNO>
Ising-model description of the SU(2)_1 quantum critical point in a


  A nonperturbative analytical description of the SU(2)_1 quantum critical
point in an explicitly dimerized two-leg spin-1/2 Heisenberg ladder is
presented. It is shown that this criticality essentially coincides with that
emerging in a weakly dimerized spin-1 chain with a small Haldane gap. The
approach is based on the mapping onto an SO(3)-symmetric model of three
strongly coupled quantum Ising chains. This mapping is used to establish the
correspondence between all physical fields of the spin ladder and those
characterizing the SU(2)_1 criticality at the infrared fixed point.

</DOC>
<DOC>
<DOCNO> 12573 </DOCNO>
Poissonian reducibility and thermal scaling within the lattice gas model


  The emission of clusters in the nuclear disassembly is investigated within
the framework of isospin dependent lattice gas model and classical molecular
dynamics model. As observed in the recent experimental data, it is found that
the emission of individual cluster is poissonian and thermal scaling is
observed in the linear Arrhenius plots made from the average multiplicity of
each cluster. The mass, isotope and charge dependent "emission barriers" are
extracted from the slopes of the Arrhenius plots and their possible physical
implications are investigated.

</DOC>
<DOC>
<DOCNO> 100829 </DOCNO>
Rademacher chaos in symmetric spaces


  Necessary and sufficient conditions for the equivalence of the Rademacher
chaos to the canonical basis of l_2 and also for the complementability of the
corresponding generated subspace are derived. In particular, we obtain the
unimprovability of the exponential integrability of functions from this space.

</DOC>
<DOC>
<DOCNO> 84522 </DOCNO>
Scale Invariance, Inflation and the Present Vacuum Energy of the


  The possibility of mass in the context of scale-invariant, generally
covariant theories, is discussed. Scale invariance is considered in the context
of a gravitational theory where the action, in the first order formalism, is of
the form $S = \int L_{1} \Phi d^4x$ + $\int L_{2}\sqrt{-g}d^4x$ where $\Phi$ is
a density built out of degrees of freedom independent of the metric. For global
scale invariance, a "dilaton" $\phi$ has to be introduced, with non-trivial
potentials $V(\phi)$ = $f_{1}e^{\alpha\phi}$ in $L_1$ and $U(\phi)$ =
$f_{2}e^{2\alpha\phi}$ in $L_2$. This leads to non-trivial mass generation and
a potential for $\phi$ which is interesting for inflation. The model after ssb
can be connected to the induced gravity model of Zee, which is a successful
model of inflation. Models of the present universe and a natural transition
from inflation to a slowly accelerated universe at late times are discussed.

</DOC>
<DOC>
<DOCNO> 13953 </DOCNO>
Electronic Mechanism of Superconductivity in the Cuprates, C$_{60}$, and


  On the basis of an analysis of theoretical and numerical studies of model
systems, and of experiments on superconductivity in doped C$_{60}$, polyacenes,
and the cuprate high temperature superconductors, we propose that a purely
electronic mechanism of superconductivity requires structures at an
intermediate or mesoscale. Specifically, we address the crucial question of how
high temperature superconducting pairing on the mesoscale can arise from purely
repulsive electronic interactions.

</DOC>
<DOC>
<DOCNO> 117233 </DOCNO>
The 1st Law of Thermodynamics in Chemical Reactions


  In the previous papers of the author it has been shown that the 1st law of
thermodynamics in chemical reactions is the following one: dU=dQ+PdV+SUM In the
present paper this theory was developed and it has been shown that the 1st law
of thermodynamics in chemical reactions has the following form: dC=-dU+dA and
-dU=dQ where dC is the change in the chemical energy, dU is the change in the
internal energy. Internal energy is the energy of thermal motion of molecules.

</DOC>
<DOC>
<DOCNO> 72098 </DOCNO>
Radiatively Induced Lorentz and CPT Violation in QED at Finite


  In this paper we evaluate the induced Lorentz and CPT violating Chern-Simons
term in the QED action at finite temperature. We do this using the method of
derivative expansion of fermion determinants. Also, we use the imaginary-time
formalism to calculate the temperature dependence of the Chern-Simons term

</DOC>
<DOC>
<DOCNO> 84913 </DOCNO>
Path Integral Quantisation of Finite Noncommutative Geometries


  We present a path integral formalism for quantising the spectral action of
noncommutative geometry, based on the principle of summing over all Dirac
operators. The approach is demonstrated on two simple finite noncommutative
geometries. On the first, the graviton is described by a Higgs field, and on
the second, it is described by a gauge field. We start with the partition
function, and calculate the propagator and Greens functions for the gravitons.
The expectation values for the distances are evaluated, and we discover that
distances can shrink with increasing graviton excitations. We find that adding
fermions reduces the effects of the gravitational field. We also make a
comparison with Rovelli's canonical quantisation approach described in [1], and
briefly discuss the quantisation of a Riemannian manifold.

</DOC>
<DOC>
<DOCNO> 170592 </DOCNO>
Branch points in the complex plane and information loss in quantum


  The mechanism of avoided level crossings in quantum systems is studied. It is
traced back to the existence of branch points in the complex plane which
influence the properties of resonance states as well as of discrete states. An
avoided level crossing of two states causes not only an exchange of the two
wave functions but, above all, correlations between them. The correlations play
an important role at high level density since they cause the loss of
information on the individual properties of the states.

</DOC>
<DOC>
<DOCNO> 169601 </DOCNO>
Quantum Decoherence from Adiabatic Entanglement


  In order to understand quantum decoherence of a quantum system due to its
interaction with a large system behaving classically, we introduce the concept
of adiabatic quantum entanglement based on the Born-Oppenhemeir approximation.
In the adiabatic limit, it is shown that the wave function of the total system
formed by the quantum system plus the large system can be factorized as an
entangled state with correlation between adiabatic quantum states and
quasi-classical motion configurations of the large system. In association with
a novel viewpoint about quantum measurement, which has been directly verified
by most recent experiments [e.g, S. Durr et.al, Nature 33, 359 (1998)], it is
shown that the adiabatic entanglement is indeed responsible for the quantum
decoherence and thus it can be regarded as a "clean" quantum measurement when
the large system behaves as a classical object. The large system being taken
respectively to be a macroscopically distinguishable spatial variable, a high
spin system and a harmonic oscillator with a coherent initial state, three
illustrations are present with their explicit solutions in this paper.

</DOC>
<DOC>
<DOCNO> 120493 </DOCNO>
N-body simulations of self-gravitating gas in stationary fragmented


  The interstellar medium is observed in a hierarchical fractal structure over
several orders of magnitude in scale. Aiming to understand the origin of this
structure, we carry out numerical simulations of molecular cloud fragmentation,
taking into account self-gravity, dissipation and energy input. Self-gravity is
computed through a tree code, with fully or quasi periodic boundary conditions.
Energy dissipation is introduced through cloud-cloud ineslatic collisions.
Several schemes are tested for the energy input. It appears that energy input
from galactic shear allows to achieve a stationary clumped state for the gas,
avoiding final collapse. When a stationary turbulent cascade is established, it
is possible to derive meaningful statistical studies on the data such as the
fractal dimension of the mass distribution.

</DOC>
<DOC>
<DOCNO> 170104 </DOCNO>
Phase noise measurement in a cavity with a movable mirror undergoing


  We study the dynamics of an optical mode in a cavity with a movable mirror
subject to quantum Brownian motion. We study the phase noise power spectrum of
the output light, and we describe the mirror Brownian motion, which is
responsible for the thermal noise contribution, using the quantum Langevin
approach. We show that the standard quantum Langevin equations, supplemented
with the appropriate non-Markovian correlation functions, provide an adequate
description of Brownian motion.

</DOC>
<DOC>
<DOCNO> 118899 </DOCNO>
Electron, Muon, and Hadron Lateral Distributions Measured in Air-Showers


  Measurements of electron, muon, and hadron lateral distributions of extensive
air showers as recorded by the KASCADE experiment are presented. The data cover
the energy range from about 5x10^14 eV up to almost 10^17 eV and extend from
the inner core region to distances of 200 m. The electron and muon
distributions are corrected for mutual contaminations by taking into account
the detector properties in the experiment. All distributions are well described
by NKG-functions. The scale radii describing the electron and hadron data best
are approx. 30 m and 10 m, respectively. We discuss the correlation between
scale radii and `age' parameter as well as their dependence on shower size,
zenith angle, and particle energy threshold.

</DOC>
<DOC>
<DOCNO> 121027 </DOCNO>
Detectability of Gravitational Lensing Effect on the Two-point


  We present quantitative investigations of the weak lensing effect on the
two-point correlation functions of local maxima (hotspots),
  $\xipk(\theta)$, in the cosmic microwave background (CMB) maps. The lensing
effect depends on the projected mass fluctuations between today and the
redshift $z_{\rm rec}\approx1100$. If adopting the Gaussian assumption for the
primordial temperature fluctuations field, the peak statistics can provide an
additional information about the intrinsic distribution of hotspots that those
pairs have some characteristic separation angles. The weak lensing then
redistributes hotspots in the observed CMB maps from the intrinsic distribution
and consequently imprints non-Gaussian signatures onto $\xipk(\theta)$.
Especially, since the intrinsic $\xipk(\theta)$ has a pronounced depression
feature around the angular scale of $\theta\approx 70'$ for a flat universe,
the weak lensing induces a large smoothing at the scale. We show that the
lensing signature therefore has an advantage to effectively probe mass
fluctuations with large wavelength modes around $\lambda\approx 50 h^{-1}{\rm
Mpc}$. To reveal the detectability, we performed numerical experiments with
specifications of {\em MAP} and {\em Planck Surveyor} including the
instrumental effects of beam smoothing and detector noise. It is then found
that our method can successfully provide constraints on amplitude of the mass
fluctuations and cosmological parameters in a flat universe with and without
cosmological constant, provided that we use maps with 65% sky coverage expected
from Planck.

</DOC>
<DOC>
<DOCNO> 119761 </DOCNO>
Turbulence in the Solar Photosphere


  The precise nature of photospheric flows, and of the transport effects they
give rise to, has been the subject of intense debate in the last decade. Here
we attempt to give a brief review of the subject emphasizing interdisciplinary
(solar physics - turbulence theory) aspects, key open questions, and recent
developments.

</DOC>
<DOC>
<DOCNO> 13906 </DOCNO>
Suppression of tunneling into multi-wall carbon nanotubes


  We have studied tunneling of electrons into multi-wall carbon nanotubes.
Nanotube/electrode interfaces with low transparency as well as
nanotube/nanotube junctions created with atomic force microscope manipulation
have been used. The tunneling conductance goes to zero as the temperature and
bias are reduced, and the functional form is consistent with a power law
suppression of tunneling as a function of energy. The exponent depends upon
sample geometry. The relationship between these results and theories for
tunneling into ballistic and disordered metals is discussed.

</DOC>
<DOC>
<DOCNO> 102121 </DOCNO>
On some $\cal D$-modules in dimension 2


  We prove a duality formula for two ${\cal D}$-modules arising from
logarithmic derivations w.r.t. a plane curve. As an application we give a
differential proof of a logarithmic comparison theorem of
Calder\'on-Mond-Narv\'aez-Castro.

</DOC>
<DOC>
<DOCNO> 13349 </DOCNO>
Approximate Ginzburg-Landau solution for the regular flux-line lattice.


  A variational model is proposed to describe the magnetic properties of
type-II superconductors in the entire field range between $H_{c1}$ and $H_{c2}$
for any values of the Ginzburg-Landau parameter $\kappa>1/\sqrt{2}$. The
hexagonal unit cell of the triangular flux-line lattice is replaced by a circle
of the same area, and the periodic solutions to the Ginzburg-Landau equations
within this cell are approximated by rotationally symmetric solutions. The
Ginzburg-Landau equations are solved by a trial function for the order
parameter. The calculated spatial distributions of the order parameter and the
magnetic field are compared with the corresponding distributions obtained by
numerical solution of the Ginzburg-Landau equations. The comparison reveals
good agreement with an accuracy of a few percent for all $\kappa$ values
exceeding $\kappa \approx 1$. The model can be extended to anisotropic
superconductors when the vortices are directed along one of the principal axes.
The reversible magnetization curve is calculated and an analytical formula for
the magnetization is proposed. At low fields, the theory reduces to the London
approach at $\kappa \gg 1$, provided that the exact value of $H_{c1}$ is used.
At high fields, our model reproduces the main features of the well-known
Abrikosov theory. The magnetic field dependences of the reversible
magnetization found numerically and by our variational method practically
coincide. The model also refines the limits of some approximations which have
been widely used. The calculated magnetization curves are in a good agreement
with experimental data on high-T$_c$ superconductors.

</DOC>
<DOC>
<DOCNO> 178748 </DOCNO>
$E1-E2$ interference in the Coulomb dissociation of $^8$B


  We investigate the effects arising out of the $E1 - E2$ interference in the
Coulomb dissociation of $^8$B at beam energies below and around 50 MeV/nucleon.
The theory has been formulated within a first order semiclassical scheme of
Coulomb excitation, in which both the ground state and the continuum state wave
functions of $^8$B enter as inputs. We find that the magnitude of the
interference could be large in some cases. However, there are some specific
observables which are free from the effects of the $E1 - E2$ interference,
which is independent of the models used to describe the structure of $^8$B.
This will be useful for the analysis of the breakup data in relation to the
extraction of the astrophysical factor $S_{17}(0)$.

</DOC>
<DOC>
<DOCNO> 70265 </DOCNO>
Attractive Forces Between Global Monopoles and Domain Walls


  We study the interaction between stable monopoles and domain walls in a
$SO(3) \times Z(2)$ scalar field theory. Numerical simulations reveal that
there is an attractive force between the monopole and the wall, but that after
the monopole and the wall collide, the monopole does not unwind. We present an
analytic explanation for the origin of the attractive force, and conclude that
this is a generic feature of monopole-wall interactions which does not depend
on the detailed structure of the model. The existence of the attractive force
supports the hypothesis of Dvali {\em et al.} (hep-ph/9710301), who proposed
that monopoles can be ``swept up'' by domain walls, thereby alleviating or
solving the monopole problem associated with phase transitions occurring after
or in the absence of inflation.

</DOC>
<DOC>
<DOCNO> 83496 </DOCNO>
A General Framework for Automatic Termination Analysis of Logic Programs


  This paper describes a general framework for automatic termination analysis
of logic programs, where we understand by ``termination'' the finitenes s of
the LD-tree constructed for the program and a given query. A general property
of mappings from a certain subset of the branches of an infinite LD-tree into a
finite set is proved. From this result several termination theorems are
derived, by using different finite sets. The first two are formulated for the
predicate dependency and atom dependency graphs. Then a general result for the
case of the query-mapping pairs relevant to a program is proved (cf.
\cite{Sagiv,Lindenstrauss:Sagiv}). The correctness of the {\em TermiLog} system
described in \cite{Lindenstrauss:Sagiv:Serebrenik} follows from it. In this
system it is not possible to prove termination for programs involving
arithmetic predicates, since the usual order for the integers is not
well-founded. A new method, which can be easily incorporated in {\em TermiLog}
or similar systems, is presented, which makes it possible to prove termination
for programs involving arithmetic predicates. It is based on combining a finite
abstraction of the integers with the technique of the query-mapping pairs, and
is essentially capable of dividing a termination proof into several cases, such
that a simple termination function suffices for each case. Finally several
possible extensions are outlined.

</DOC>
<DOC>
<DOCNO> 169721 </DOCNO>
Cavity Field Reconstruction at Finite Temperature


  We present a scheme to reconstruct the quantum state of a field prepared
inside a lossy cavity at finite temperature. Quantum coherences are normally
destroyed by the interaction with an environment, but we show that it is
possible to recover complete information about the initial state (before
interaction with its environment), making possible to reconstruct any
$s$-parametrized quasiprobability distribution, in particular, the Wigner
function.

</DOC>
<DOC>
<DOCNO> 120545 </DOCNO>
The Mg II and Lyman-alpha Lines of Nearby K Dwarfs: ISM Components and


  We analyze local ISM absorption observed in the Lyman-alpha and Mg II h & k
lines of six nearby K dwarf stars, using UV spectra of these stars obtained
with the Goddard High Resolution Spectrograph on the Hubble Space Telescope.
For four of the six stars, we detect an absorption component with a velocity
and column density consistent with the Local Interstellar Cloud (LIC). For HD
197890, there is no observed component at the expected LIC velocity, or at the
projected velocity of the G cloud, which is a nearby cloud in the general
direction of the Galactic Center. It also seems doubtful that either of the two
components seen toward HD 82558 are LIC or G cloud absorption. The total H I
column density toward HD 82558 (d=18.3 pc) is extremely high (log N(H)=19.05
+/- 0.15), representing the largest average H I density detected for any line
of sight through the nearby LISM (n(H)=0.2 cm^-3). This is particularly
remarkable considering that this star is only 39 degrees from the "interstellar
tunnel" toward Epsilon CMa, where column densities are an order of magnitude
lower than this toward stars which are an order of magnitude farther away.

</DOC>
<DOC>
<DOCNO> 123021 </DOCNO>
The MAP satellite mission to map the CMB anisotropy


  The Microwave Anisotropy Probe (MAP) satellite is scheduled to launch in
mid-2001. MAP's goal is to produce a map of the anisotropy in the cosmic
microwave background of unprecedented accuracy and precision. The guiding
design principle has been the minimization of systematic effects. The
instrument design and mapping strategy work in concert to take advantage of the
unique opportunities afforded by deep space. We give an overview of the mission
and compare the projected MAP error bars to recent measurements.

</DOC>
<DOC>
<DOCNO> 179015 </DOCNO>
Photonic Probes of the Deuteron in Effective Field Theory


  I give a taste of recent progress in using chiral perturbation theory to
understand nucleon and deuteron structure.

</DOC>
<DOC>
<DOCNO> 80856 </DOCNO>
Progress using generalized lattice Dirac operators to parametrize the


  We report on an ongoing project to parametrize the Fixed-Point Dirac operator
for massless quarks, using a very general construction which has arbitrarily
many fermion offsets and gauge paths, the complete Clifford algebra and
satisfies all required symmetries. Optimizing a specific construction with
hypercubic fermion offsets, we present some preliminary results.

</DOC>
<DOC>
<DOCNO> 102168 </DOCNO>
Basics of the b-calculus


  R. B. Melrose's b-calculus provides a framework for dealing with problems of
partial differential equations that arise in singular or degenerate geometric
situations. This article is a somewhat informal short course introducing many
of the basic ideas of this world, assuming little more than a basic analysis
and manifold background. As examples, classical pseudodifferential operators on
manifolds and b-pseudodifferential (also known as totally characteristic)
operators on manifolds with boundary are discussed.

</DOC>
<DOC>
<DOCNO> 120605 </DOCNO>
Low-mass spectroscopic binaries in the Hyades: a candidate brown dwarf


  We have used the HIRES echelle spectrograph in the Keck I telescope to obtain
high-resolution spectroscopy of 51 late-type M dwarfs in the Hyades cluster.
Cross-correlating the calibrated data against spectra of white dwarfs allows us
to determine heliocentric velocities with an accuracy of +/- 0.3 km/s. Twenty
seven stars were observed at two epochs in 1997; two stars, RHy 42 and RHy 403,
are confirmed spectroscopic binaries. RHY 42 is a double-lined, equal-mass
system; RHy 403 is a single-lined, short-period binary, P ~ 1.275 days. RHy
403A has an absolute magnitude of M_I = 10.85, consistent with a mass of 0.15
M(Sun). The systemic mass function has a value of 0.0085, which, combined with
the non-detection of a secondary peak in the cross-correlation function,
implies 0.095 > M_2 > 0.06 M (Sun), and the strong possibility that the
companion is the first Hyades brown dwarf to be identified. Unfortunately, the
maximum expected angular separation in the system is only 0.25 mas. Five other
low-mass Hyads are identified as possible spectroscopic binaries, based either
on repeat observations or comparison between the observed radial velocity and
the value expected for Hyades cluster members. Combined with HST imaging data,
we infer a binary fraction between 23 and 30 . All of the stars are
chromospherically active. RHy 281 was caught in mid-flare and, based on that
detection, we estimate a flaring frequency of 2.5% for low-mass Hyades stars.
Nine stars have rotational velocities, v sin(i), exceeding 20 km/s and most of
the sample have detectable rotation. We examine the H-alpha emission
characteristics of low-mass cluster members and show that there is no evidence
for a correlation with rotation.

</DOC>
<DOC>
<DOCNO> 85420 </DOCNO>
Theory of Relativistic Reference Frames for High-Precision Astrometric


  Recent modern space missions deliver invaluable information about origin of
our universe, physical processes in the vicinity of black holes and other
exotic astrophysical objects, stellar dynamics of our galaxy, etc. On the other
hand, space astrometric missions make it possible to determine with
unparalleled precision distances to stars and cosmological objects as well as
their physical characteristics and positions on the celestial sphere.
Permanently growing accuracy of space astronomical observations and the urgent
need for adequate data processing algorithms require corresponding development
of an adequate theory of reference frames along with unambiguous description of
propagation of light rays from a source of light to observer. Such a theory
must be based on the Einstein's general relativity and account for numerous
relativistic effects both in the solar system and outside of its boundary. The
main features of the relativistic theory of reference frames are presented in
this work. A hierarchy of the frames is described starting from the perturbed
cosmological Friedmann-Robertson-Walker metric and going to the observer's
frame through the intermediate barycentric and geocentric frames in the solar
system. Microarcsecond astrometry and effects of propagation of light rays in
time-dependent gravitational fields are discussed as well.

</DOC>
<DOC>
<DOCNO> 70665 </DOCNO>
A manifestation of a gluon saturation in e-A DIS


  This is a short presentation of our talks given at eRHIC Workshop at the BNL.
We give here a status report of our attempts to understand how gluon saturation
will manifest itself in deep inelastic scattering with nuclei. This summary
reflects our current understanding and shows directions of our research rather
then a final answer to the question. Nevertheless, we are able to share with
our reader our tentative answer to the question:``Why do we need to measure DIS
with nuclei and why these data will be complementary to the information
obtained from proton DIS".

</DOC>
<DOC>
<DOCNO> 68660 </DOCNO>
Day - Night Effect Predictions for the SNO Detector


  Detailed predictions for the day-night (D-N) asymmetry in the
energy-integrated one year signals in the SNO detector in the case of the MSW
$\nu_e \to \nu_{\mu(\tau)}$ and/or $\nu_e \to \nu_s$ transition solutions of
the solar neutrino problem are presented. The asymmetries in the charged
current (CC) and $\nu - e^{-}$ elastic scattering (ES) event rates are
calculated for both MSW solutions; in the case of the $\nu_e \to \nu_s$
transition solution the D-N asymmetry in the neutral current (NC) event rate
are derived as well. The asymmetries are calculated for three night samples of
events which are produced by the solar neutrinos crossing i) the Earth mantle
only (Mantle), ii) the Earth core (Core) and iii) the Earth core and/or the
mantle (Night). The effects of the uncertainties, e.g., in the values of the
cross-sections of the CC and NC neutrino-induced reactions on deuterium on the
corresponding D-N asymmetry predictions are analyzed. It is shown, in
particular, that that due to the strong enhancement of the transitions of the
solar neutrinos crossing the Earth core, at $\sin^22\theta_V \leq 0.01$ the
corresponding one year average D-N asymmetry in the Core sample of CC events in
the case of the $\nu_e \to \nu_{\mu(\tau)}$ solution can be larger by a factor
of up to $\sim 8$ than the asymmetry in the Night sample. Iso - (D-N) asymmetry
contours in the $\Delta m^2 - \sin^22\theta_V$ plane for the SNO detector are
derived in the region $\sin^22\theta_V \gsim 10^{-4}$ for the Core and Night
samples of the CC, ES and NC events.

</DOC>
<DOC>
<DOCNO> 123063 </DOCNO>
On the atmospheric fragmentation of small asteroids


  It is known, from observational data recorded from airbursts, that small
asteroids breakup at dynamical pressures lower than their mechanical strength.
This means that actual theoretical models are inconsistent with observations.
In this paper, we present a detailed discussion about data recorded from
airbursts and about several theoretical models. We extend and improve a theory
previously outlined for the fragmentation of small asteroids in the Earth
atmosphere. The new condition for fragmentation is given by the shock
wave-turbulence interaction, which results in sudden outburst of the dynamical
pressure.

</DOC>
<DOC>
<DOCNO> 10486 </DOCNO>
On the interpretation of spin-polarized electron energy loss spectra


  We study the origin of the structure in the spin-polarized electron energy
loss spectroscopy (SPEELS) spectra of ferromagnetic crystals. Our study is
based on a 3d tight-binding Fe model, with constant onsite Coulomb repulsion U
between electrons of opposite spin. We find it is not the total density of
Stoner states as a function of energy loss which determines the response of the
system in the Stoner region, as usually thought, but the densities of Stoner
states for only a few interband transitions. Which transitions are important
depends ultimately on how strongly umklapp processes couple the corresponding
bands. This allows us to show, in particular, that the Stoner peak in SPEELS
spectra does not necessarily indicate the value of the exchange splitting
energy. Thus, the common assumption that this peak allows us to estimate the
magnetic moment through its correlation with exchange splitting should be
reconsidered, both in bulk and surface studies. Furthermore, we are able to
show that the above mechanism is one of the main causes for the typical
broadness of experimental spectra. Finally, our model predicts that optical
spin waves should be excited in SPEELS experiments.

</DOC>
<DOC>
<DOCNO> 150968 </DOCNO>
A Semi-Infinite Construction of Unitary N=2 Modules


  We show that each unitary representation of the N=2 superVirasoro algebra can
be realized in terms of ``collective excitations'' over a filled Dirac sea of
fermionic operators satisfying a generalized exclusion principle. These are
semi-infinite forms in the modes of one of the fermionic currents. The
constraints imposed on the fermionic operators have a counterpart in the form
of a model one-dimensional lattice system, studying which allows us to prove
the existence of a remarkable monomial basis in the semi-infinite space. This
leads to a Rogers--Ramanujan-like character formula. We construct the N=2
action on the semi-infinite space using a filtration by finite-dimensional
subspaces (the structure of which is related to the supernomial coefficients);
the main technical tool is provided by the dual functional realization. As an
application, we identify the coinvariants with the dual to a space of
meromorphic functions on products of punctured Riemann surfaces with a
prescribed behaviour on multiple diagonals. For products of punctured $CP^1$,
such spaces are related to the unitary N=2 fusion algebra, for which we also
give an independent derivation.

</DOC>
<DOC>
<DOCNO> 39807 </DOCNO>
What is the Usefulness of Frequentist Confidence Intervals?


  The following questions are discussed: ``Why confidence intervals are a hot
topic?''; ``Are confidence intervals objective?''; ``What is the usefulness of
coverage?''; ``How to obtain useful information from experiment?''; ``The
confidence level must be chosen independently from the knowledge of the
data?''.

</DOC>
<DOC>
<DOCNO> 9693 </DOCNO>
A Model to Describe Transport Properties in


  A pseudo-spin model is proposed, as a means to describe some transport
properties (resistivity and Hall mobility) in
$Bi_2Sr_2(Ca_zPr_{1-z})Cu_2O_{8+y}$. Our model is based in a double-well
potential where tunneling in a given site and interaction between different
lattice sites are allowed only through the excited states. Doping of the pure
system by the addition of $Pr$ increases the ratio between the activation
energy and the tunneling constant. The model Hamiltonian displays some features
which are present in the hydrogen-bonded ferroelectrics. Its dynamics is
treated in the random phase approximation and the characteristic frequency
(time) is used in a Drude formula in order to obtain some transport properties
of the system, namely the electric resistivity and the Hall mobility. The
quantities calculated in this work are compared with the experimental data of
B. Beschoten, S. Sadewasser, G. G\"{u}ntherodt and C. Quitmann [Phys. Rev.
Lett.77, 1837(1996)].

</DOC>
<DOC>
<DOCNO> 169824 </DOCNO>
Effectively classical quantum states for open systems


  Notions of robust and "classical" states for an open quantum system are
introduced and discussed in the framework of the isometric-sweeping
decomposition of trace class operators. Using the predictability sieve proposed
by Zurek, ``quasi-classical'' states are defined. A number of examples
illustrating how the ``quasi-classical'' states correspond to classical points
in phase space connected with the measuring apparatus are presented.

</DOC>
<DOC>
<DOCNO> 9077 </DOCNO>
New collective states of 2D electrons in high Landau levels


  A brief summary of the emerging evidence for a new class of collective states
of two-dimensional electrons in partially occupied excited Landau levels is
presented. Among the most dramatic phenomena described are the large
anisotropies of the resistivity observed at very low temperatures near
half-filling of the third and higher Landau levels and the non-linear character
of the re-entrant integer quantized Hall states in the flanks of the same
levels. The degree to which these findings support recent theoretical
predictions of charge density wave ground states is discussed and a preliminary
comparison to recent transport theories is made.

</DOC>
<DOC>
<DOCNO> 67778 </DOCNO>
The Reconstruction of Trilinear Higgs Couplings


  To establish the Higgs mechanism {\it sui generis} experimentally, the Higgs
self-interaction potential must be reconstructed. This task requires the
measurement of the trilinear and quadrilinear self-couplings, as predicted in
the Standard Model or in supersymmetric theories. The couplings can be probed
in multiple Higgs production at high-luminosity e+e- linear colliders. We
present the theoretical analysis for the production of neutral Higgs-boson
pairs in the relevant channels of double Higgs-strahlung and associated
multiple Higgs production.

</DOC>
<DOC>
<DOCNO> 117208 </DOCNO>
Comment on ``Do Zero-energy Solutions of Maxwell Equations Have the


  This is the answer to objections put forth in Proceedings of the Zacatecas
Workshop "Lorentz Group, CPT and Neutrinos" (World Scientific, Singapore,
2000), pp. 335-341.

</DOC>
<DOC>
<DOCNO> 178464 </DOCNO>
Evidence for a New State of Matter: An Assessment of the Results from


  This "position paper" collects the scientific arguments behind the CERN Press
Release of February 10, 2000, which announced evidence for the creation of a
new state of matter in Pb-Pb collisions at the CERN SPS. The data on which this
paper is based were presented in a special seminar at CERN on the same day, a
recording of which can be accessed at
http://www.cern.ch/CERN/Announcements/2000/NewStateMatter/ .

</DOC>
<DOC>
<DOCNO> 101194 </DOCNO>
Indecomposable set-theoretical solutions to the Quantum Yang-Baxter


  In this paper we show that all indecomposable nondegenerate set-theoretical
solutions to the Quantum Yang-Baxter equation on a set of prime order are
affine, which allows us to give a complete and very simple classification of
such solutions. This result is a natural application of the general theory of
set-theoretical solutions to the quantum Yang-Baxter equation. It is also a
generalization of the corresponding statement for involutive set-theoretical
solutions proved in an earlier paper of P.E. and A.S. with T.Schedler.
  In order to prove our main result, we use the classification theory developed
by the third author (based on the ideas of Lu, Yan, and Zhu) to reduce the
problem to a group-theoretical statement: a finite group with trivial center
generated by a conjugacy class of prime order is a subgroup of the affine
group. Unfortunalely, we did not find an elementary proof of this statement,
and our proof relies on the classification of outer automorphisms of finite
simple groups.

</DOC>
<DOC>
<DOCNO> 72333 </DOCNO>
Quantum theory's last challenge


  Quantum mechanics is now 100 years old and still going strong. Combining
general relativity with quantum mechanics is the last hurdle to be overcome in
the "quantum revolution".

</DOC>
<DOC>
<DOCNO> 7627 </DOCNO>
A hydrodynamic approach to the Bose-Glass transition


  Nonlinear hydrodynamics is used to evaluate disorder-induced corrections to
the vortex liquid tilt modulus for finite screening length and arbitrary
disorder geometry. Explicit results for aligned columnar defects yield a
criterion for locating the Bose glass transition line at all fields.

</DOC>
<DOC>
<DOCNO> 123154 </DOCNO>
The Interstellar Medium of Star-forming Irregular Galaxies: The View


  We present mid-infrared imaging and far-infrared (FIR) spectroscopy of 5 IBm
galaxies observed by ISO as part of our larger study of the inter- stellar
medium of galaxies. Most of the irregulars in our sample are very actively
forming stars. The mid-infrared imaging was in a band centered at 6.75 microns
that is dominated by polycyclic aromatic hydrocarbons (PAHs) and in a band
centered at 15 microns that is dominated by small dust grains. The spectroscopy
of 3 of the galaxies includes [CII]158 microns and [OI]63 microns, important
coolants of photodissociation regions (PDRs), and [OIII]88 microns and [NII]122
microns, which come from ionized gas. [OI]145 microns and [OIII]52 microns were
measured in one galaxy as well. These data are combined with PDR and HII region
models to deduce properties of the interstellar medium of these galaxies.

</DOC>
<DOC>
<DOCNO> 120445 </DOCNO>
On the effect of coronal outflow on spectra formation in galactic black


  We present the results of both analytical and numerical calculations of the
amplitude of the reflection component in X-ray spectra of galactic black hole
systems. We take into account the anisotropy of Compton scattering and the
systematic relativistic bulk motion of the hot plasma. In the case of single
scattering approximation the reflection from the disc surface is significantly
enhanced due to the anisotropy of Compton scattering. On the other hand the
calculations of multiple scattering obtained using the Monte Carlo method show
that the anisotropy effect is much weaker in that case. Therefore, the enhanced
backscattered flux may affect the observed spectra only if the disc surface is
highly ionized, which reduces the absorption in the energy band corresponding
to the first Compton scattering.

</DOC>
<DOC>
<DOCNO> 123072 </DOCNO>
Master Equation for Hydrogen Recombination on Grain Surfaces


  Recent experimental results on the formation of molecular hydrogen on
astrophysically relevant surfaces under conditions similar to those encountered
in the interstellar medium provided useful quantitative information about these
processes. Rate equation analysis of experiments on olivine and amorphous
carbon surfaces provided the activation energy barriers for the diffusion and
desorption processes relevant to hydrogen recombination on these surfaces.
However, the suitability of rate equations for the simulation of hydrogen
recombination on interstellar grains, where there might be very few atoms on a
grain at any given time, has been questioned. To resolve this problem, we
introduce a master equation that takes into account both the discrete nature of
the H atoms and the fluctuations in the number of atoms on a grain. The
hydrogen recombination rate on microscopic grains, as a function of grain size
and temperature, is then calculated using the master equation. The results are
compared to those obtained from the rate equations and the conditions under
which the master equation is required are identified.

</DOC>
<DOC>
<DOCNO> 102889 </DOCNO>
Sharp Lipschitz estimates for operator $\bar\partial_M$ on a


  We construct integral homotopy operators on a regular CR manifold and prove
sharp estimates for these operators in a special Lipschitz scale.

</DOC>
<DOC>
<DOCNO> 170523 </DOCNO>
Understanding quantum effects from classical principles


  Dynamics of a particle is formulated from classical principles that are
amended by the uncertainty principle. Two best known quantum effects:
interference and tunneling are discussed from these principles. It is shown
that identical to quantum results are obtained by solving only classical
equations of motion. Within the context of interference Aharonov-Bohm effect is
solved as a local action of magnetic force on the particle. On the example of
tunneling it is demonstrated how uncertainty principle amends traditional
classical mechanics: it allows the momentum of the particle to change without
the force being the cause of it.

</DOC>
<DOC>
<DOCNO> 12179 </DOCNO>
Luttinger revisted-the renormalization group approach


  Luttinger's contributions abound in different parts of many-body physics.
Here I review the ones that appear when one uses the Renormalization Group (RG)
to study the subject: the Luttinger Liquid, Luttinger's Theorem (on the volume
of the Fermi surface) and the Kohn-Luttinger Theorem on the superconducting
instability of all metals as one approaches absolute zero.

</DOC>
<DOC>
<DOCNO> 150588 </DOCNO>
Axial Anomaly in Noncommutative QED on R^4


  The axial anomaly of the noncommutative U(1) gauge theory is calculated by a
number of methods and compared with the commutative one. It is found to be
given by the corresponding Chern class.

</DOC>
<DOC>
<DOCNO> 117915 </DOCNO>
ASCA and BeppoSAX observations of the peculiar X-ray source


  The X-ray source 4U1700+24/HD154791 is one of the few galactic sources whose
counterpart is an evolved M star. In X-rays the source shows extreme erratic
variability and a complex and variable spectrum. While this strongly suggests
accretion onto a compact object, no clear diagnosis of binarity was done up to
now. We report on ASCA and BeppoSAX X-ray broad band observations of this
source and on ground optical observations from the Loiano 1.5 m telescope.

</DOC>
<DOC>
<DOCNO> 68472 </DOCNO>
Kalb-Ramond axion production in anisotropic string cosmologies


  We compute the energy spectra for massless Kalb-Ramond axions in
four-dimensional anisotropic string cosmological models. We show that, when
integrated over directions, the four-dimensional anisotropic model leads to
infra-red divergent spectra similar to the one found in the isotropic case.

</DOC>
<DOC>
<DOCNO> 12588 </DOCNO>
Quantum vortex fluctuations in cuprate superconductors


  We study the effects of quantum vortex fluctuations in two-dimensional
superconductors using a dual theory of vortices, and investigate the relevance
to underdoped cuprates where the superconductor-insulator transition (SIT) is
possibly driven by quantum vortex proliferation. We find that a broad enough
phase fluctuation regime may exist for experimental observation of the quantum
vortex fluctuations near SIT in underdoped cuprates. We propose that this
scenario can be tested via pair-tunneling experiments which measure the
characteristic resonances in the zero-temperature pair-field susceptibility in
the vortex-proliferated insulating phase.

</DOC>
<DOC>
<DOCNO> 122356 </DOCNO>
The Galaxy Environment of a Quasar at z=1.226: A Possible Cluster Merger


  We have conducted ultra-deep optical and deep near-infrared observations of a
field around the z=1.226 radio-quiet quasar 104420.8+055739 from the
Clowes-Campusano LQG of 18 quasars at z~1.3 in search of associated galaxy
clustering. Galaxies at these redshifts are distinguished by their
extremely-red colours, with I-K>3.75, and we find a factor ~11 overdensity of
such galaxies in a 2.25'x2.25' field centred on the quasar. In particular, we
find 15-18 galaxies with colours consistent with being a population of
passively-evolving massive ellipticals at the quasar redshift. They form
`fingers' in the V-K/K, I-K/K colour-magnitude plots at V-K~6.9, I-K~4.3
comparable to the red sequences observed in other z~1.2 clusters. We find
suggestive evidence for substructure among the red sequence galaxies in the K
image, in the form of two compact groups, 40 arcsec to the north, and 60 arcsec
to the south-east of the quasar. An examination of the wider optical images
indicates that this substructure is significant, and that the clustering
extends to form a large-scale structure 2-3 Mpc across. We find evidence for a
high (>50%) fraction of blue galaxies in this system, in the form of 15-20
`red-outlier' galaxies with I-K>3.75 and V-I<2.00, which we suggest are dusty,
star-forming galaxies at the quasar redshift. Within 30 arcsec of the quasar we
find a concentration of blue (V-I<1) galaxies in a band that bisects the two
groups of red sequence galaxies. This band of blue galaxies is presumed to
correspond to a region of enhanced star-formation. We explain this distribution
of galaxies as the early-stages of a cluster merger which has triggered both
the star-formation and the quasar.

</DOC>
<DOC>
<DOCNO> 100949 </DOCNO>
The Born Oppenheimer wave function near level crossing


  The standard Born Oppenheimer theory does not give an accurate description of
the wave function near points of level crossing. We give such a description
near an isotropic conic crossing, for energies close to the crossing energy.
This leads to the study of two coupled second order ordinary differential
equations whose solution is described in terms of the generalized
hypergeometric functions of the kind 0F3(;a,b,c;z). We find that, at low
angular momenta, the mixing due to crossing is surprisingly large, scaling like
\mu^(1/6), where \mu is the electron to nuclear mass ratio.

</DOC>
<DOC>
<DOCNO> 118720 </DOCNO>
Luminosity- and morphology-dependent clustering of galaxies


  How does the clustering of galaxies depend on their inner properties like
morphological type and luminosity? We address this question in the mathematical
framework of marked point processes and clarify the notion of luminosity and
morphological segregation. A number of test quantities such as conditional
mark-weighted two-point correlation functions are introduced. These descriptors
allow for a scale-dependent analysis of luminosity and morphology segregation.
Moreover, they break the degeneracy between an inhomogeneous fractal point set
and actual present luminosity segregation. Using the Southern Sky Redshift
Survey~2 (da Costa et al. 1998, SSRS2) we find both luminosity and
morphological segregation at a high level of significance, confirming claims by
previous works using these data (Benoist et al. 1996, Willmer et al. 1998).
Specifically, the average luminosity and the fluctuations in the luminosity of
pairs of galaxies are enhanced out to separations of 15Mpc/h. On scales smaller
than 3Mpc/h the luminosities on galaxy pairs show a tight correlation. A
comparison with the random-field model indicates that galaxy luminosities
depend on the spatial distribution and galaxy-galaxy interactions. Early-type
galaxies are also more strongly correlated, indicating morphological
segregation. The galaxies in the PSCz catalog (Saunders et al. 2000) do not
show significant luminosity segregation. This again illustrates that mainly
early-type galaxies contribute to luminosity segregation. However, based on
several independent investigations we show that the observed luminosity
segregation can not be explained by the morphology-density relation alone.

</DOC>
<DOC>
<DOCNO> 71827 </DOCNO>
HTL Resummation of the Thermodynamic Potential


  Starting from the Phi-derivable approximation scheme at leading-loop order,
the thermodynamical potential in a hot scalar theory, as well as in QED and
QCD, is expressed in terms of hard thermal loop propagators. This
nonperturbative approach is consistent with the leading-order perturbative
results, ultraviolet finite, and, for gauge theories, explicitly
gauge-invariant. For hot QCD it is argued that the resummed approximation is
applicable in the large-coupling regime, down to almost twice the transition
temperature.

</DOC>
<DOC>
<DOCNO> 117722 </DOCNO>
Search for Astronomical Sites in Developing Countries and their


  The archives of meteorological satellites permit to find around the world dry
sites well adapted to astronomical observations (in the visible, IR, and
millimetric ranges), as a pre-selection of sites. The GSM (Grating Scale
Monitor) technique permits to qualify some of them as astronomical sites for a
future setting-up of astronomical observatories. Such sites are found in new
astronomical countries or in Developing Countries. At the same time, their
preventive protection from light pollution and/or radio interference has to be
viewed. In practice, once the pre-selection is made, the government of these
countries ought to be alerted for example by IAU and/or UN Office for Outer
Space Affairs. The local site testing through GSM should be carried out in
cooperation with astronomers or scientists of these countries under the
umbrella of IAU. This should be an approach to help to introduce astronomy and
astrophysics in Developing Countries.

</DOC>
<DOC>
<DOCNO> 85495 </DOCNO>
Image distortion in non perturbative gravitational lensing


  We introduce the idea of {\it shape parameters} to describe the shape of the
pencil of rays connecting an observer with a source lying on his past
lightcone. On the basis of these shape parameters, we discuss a setting of
image distortion in a generic (exact) spacetime, in the form of three {\it
distortion parameters}. The fundamental tool in our discussion is the use of
geodesic deviation fields along a null geodesic to study how source shapes are
propagated and distorted on the path to an observer. We illustrate this
non-perturbative treatment of image distortion in the case of lensing by a
Schwarzschild black hole. We conclude by showing that there is a
non-perturbative generalization of the use of Fermat's principle in lensing in
the thin-lens approximation.

</DOC>
<DOC>
<DOCNO> 12984 </DOCNO>
Transport of a Luttinger liquid in the presence of a time dependent


  We show that the macroscopic current and charge can be formulated as a
Quantum Mechanical zero mode problem. We find that the current is given by the
velocity operator of a particle restricted to move around a circle. As an
explicit example we investigate a Luttinger liquid of length $L$ which is
perturbed by a time dependent impurity. Using the statistical mechanics of zero
modes we computed the non-equilibrium current. In particular we show that in
the low temperature limit, $L_T/L>1$, the zero mode method introduced here
becomes essential for computing the current.

</DOC>
<DOC>
<DOCNO> 8516 </DOCNO>
Relative energetics and structural properties of zirconia using a


  We describe an empirical, self-consistent, orthogonal tight-binding model for
zirconia, which allows for the polarizability of the anions at dipole and
quadrupole levels and for crystal field splitting of the cation d orbitals.
This is achieved by mixing the orbitals of different symmetry on a site with
coupling coefficients driven by the Coulomb potentials up to octapole level.
The additional forces on atoms due to the self-consistency and polarizabilities
are exactly obtained by straightforward electrostatics, by analogy with the
Hellmann-Feynman theorem as applied in first-principles calculations. The model
correctly orders the zero temperature energies of all zirconia polymorphs. The
Zr-O matrix elements of the Hamiltonian, which measure covalency, make a
greater contribution than the polarizability to the energy differences between
phases. Results for elastic constants of the cubic and tetragonal phases and
phonon frequencies of the cubic phase are also presented and compared with some
experimental data and first-principles calculations. We suggest that the model
will be useful for studying finite temperature effects by means of molecular
dynamics.

</DOC>
<DOC>
<DOCNO> 170145 </DOCNO>
Inequalities for electron-field correlation functions


  I show that there exists a class of inequalities between correlation
functions of different orders of a chaotic electron field. These inequalities
lead to the antibunching effect and are a consequence of the fact that
electrons are fermions -- indistinguishable particles with antisymmetric
states. The derivation of the inequalities is based on the known form of the
correlation functions for the chaotic state and on the properties of matrices
and determinants.

</DOC>
<DOC>
<DOCNO> 70641 </DOCNO>
Jet Asymmetry in High Energy Diffractive Production


  We propose the asymmetry in the fractional energy of charm versus anticharm
jets produced in high energy diffractive photoproduction as a sensitive test of
the interference of the Odderon (C = -) and Pomeron (C = +) exchange amplitudes
in QCD. If measured at HERA, this asymmetry could provide the first
experimental evidence of the Odderon.

</DOC>
<DOC>
<DOCNO> 8064 </DOCNO>
Clustering data by inhomogeneous chaotic map lattices


  A new approach to clustering, based on the physical properties of
inhomogeneous coupled chaotic maps, is presented. A chaotic map is assigned to
each data-point and short range couplings are introduced. The stationary regime
of the system corresponds to a macroscopic attractor independent of the initial
conditions. The mutual information between couples of maps serves to partition
the data set in clusters, without prior assumptions about the structure of the
underlying distribution of the data. Experiments on simulated and real data
sets show the effectiveness of the proposed algorithm.

</DOC>
<DOC>
<DOCNO> 101283 </DOCNO>
The Wess-Zumino term for a harmonic map


  We calculate the Wess-Zumino term $\Gamma(g)$ for a harmonic map $g$ of a
closed surface to a compact, simply connected, simple Lie group $G$ in terms of
the energy and the holonomy of the Chern-Simons line bundle on the moduli space
of flat $G$-connections. In the case of the 2-sphere we deduce that $\Gamma(g)$
is 0 or $\pi$ and for the 2-torus and $G=SU(2)$ we give a formula involving
hyperelliptic integrals.

</DOC>
<DOC>
<DOCNO> 8209 </DOCNO>
Evidence for a Goldstone Mode in a Double Layer Quantum Hall System


  The tunneling conductance between two parallel 2D electron systems has been
measured in a regime of strong interlayer Coulomb correlations. At total Landau
level filling $\nu_T=1$ the tunnel spectrum changes qualitatively when the
boundary separating the compressible phase from the ferromagnetic quantized
Hall state is crossed. A huge resonant enhancement replaces the strongly
suppressed equilibrium tunneling characteristic of weakly coupled layers. The
possible relationship of this enhancement to the Goldstone mode of the broken
symmetry ground state is discussed.

</DOC>
<DOC>
<DOCNO> 72332 </DOCNO>
Electron-Positron Jets from a Critically Magnetized Black Hole


  The curved spacetime surrounding a rotating black hole dramatically alters
the structure of nearby electromagnetic fields. The Wald field which is an
asymptotically uniform magnetic field aligned with the angular momentum of the
hole provides a convenient starting point to analyze the effects of radiative
corrections on electrodynamics in curved spacetime. Since the curvature of the
spacetime is small on the scale of the electron's Compton wavelength, the tools
of quantum field theory in flat spacetime are reliable and show that a rotating
black hole immersed in a magnetic field approaching the quantum critical value
of $B_k=m^2 c^3/(e\hbar) \approx 4.4 \times 10^{13}$~G $\approx
1.3\times10^{-11}$ cm$^{-1}$ is unstable. Specifically, a maximally rotating
three-solar-mass black hole immersed in a magnetic field of $2.3 \times
10^{12}$~G would be a copious producer of electron-positron pairs with a
luminosity of $3 \times 10^{52}$ erg s$^{-1}$.

</DOC>
<DOC>
<DOCNO> 40624 </DOCNO>
Science and Technology of BOREXINO: A Real Time Detector for Low Energy


  BOREXINO, a real-time device for low energy neutrino spectroscopy is nearing
completion of construction in the underground laboratories at Gran Sasso, Italy
(LNGS). The experiment's goal is the direct measurement of the flux of 7Be
solar neutrinos of all flavors via neutrino-electron scattering in an
ultra-pure scintillation liquid. Seeded by a series of innovations which were
brought to fruition by large scale operation of a 4-ton test detector at LNGS,
a new technology has been developed for BOREXINO. It enables sub-MeV solar
neutrino spectroscopy for the first time. This paper describes the design of
BOREXINO, the various facilities essential to its operation, its spectroscopic
and background suppression capabilities and a prognosis of the impact of its
results towards resolving the solar neutrino problem. BOREXINO will also
address several other frontier questions in particle physics, astrophysics and
geophysics.

</DOC>
<DOC>
<DOCNO> 11894 </DOCNO>
Calculation of minor hysteresis loops under metastable to stable


  We present a model in which metastable supercooled phase and stable
equilibrium phase of vortex matter coexist in different regions of a sample.
Minor hysteresis loops are calculated with the simple assumption of the two
phases of vortex matter having field-independent critical current densities. We
use our earlier published ideas that the free energy barrier separating the
metastable and stable phases reduces as the magnetic induction moves farther
from the first order phase transition line, and that metastable to stable
transformations occur in local regions of the sample when the local energy
dissipation exceeds a critical value. Previously reported anomalous features in
minor hysteresis loops are reproduced, and calculated field profiles are
presented.

</DOC>
<DOC>
<DOCNO> 9476 </DOCNO>
Vortex shedding and drag in dilute Bose-Einstein condensates


  Above a critical velocity, the dominant mechanism of energy transfer between
a moving object and a dilute Bose-Einstein condensate is vortex formation. In
this paper, we discuss the critical velocity for vortex formation and the link
between vortex shedding and drag in both homogeneous and inhomogeneous
condensates. We find that at supersonic velocities sound radiation also
contributes significantly to the drag force.

</DOC>
<DOC>
<DOCNO> 102616 </DOCNO>
Permutations Restricted by Two Distinct Patterns of Length Three


  Define $S_n(R;T)$ to be the number of permutations on $n$ letters which avoid
all patterns in the set $R$ and contain each pattern in the multiset $T$
exactly once. In this paper we enumerate $S_n(\{\alpha\};\{\beta\})$ and
$S_n(\emptyset;\{\alpha,\beta\})$ for all $\alpha \neq \beta \in S_3$. The
results for $S_n(\{\alpha\};\{\beta\})$ follow from two papers by Mansour and
Vainshtein.

</DOC>
<DOC>
<DOCNO> 178629 </DOCNO>
The decay $\rho^{0}\to \pi^{0}\pi^{0}\gamma$ and the role of


  We study the radiative decay $\rho^{0}\to\pi^{0}\pi^{0}\gamma$ within the
framework of a phenomenological approach in which the contributions of
$\sigma$-meson and $\omega$-meson intermediate states and of the pion-loops are
considered. We conclude that the $\sigma$-meson amplitude provides the dominant
contribution.

</DOC>
<DOC>
<DOCNO> 116707 </DOCNO>
Pair production and electron capture in relativistic heavy-ion


  Results are presented for simulations of electron-positron pair production in
relativistic heavy-ion collisions leading to electron capture and positron
ejection. We apply a two-center relativistic continuum distorted-wave model to
represent the electron/positron dynamics during the collision process. The
results are compared with experimental cross-section data for ${\rm La}^{57+}$
and ${\rm Au}^{79+}$ impact on Gold, Silver and Copper targets. The theory is
in very good agreement with experiment, verifying the result that the process
increases in importance with both collision energy and target atomic number,
and improves upon previous simulations of this process.

</DOC>
<DOC>
<DOCNO> 9856 </DOCNO>
Tricritical scaling at the N_t=6 chiral phase transition for 2 flavour


  We have simulated lattice QCD directly in the chiral limit of zero quark mass
by adding an additional, irrelevant 4-fermion interaction to the standard
action. Using lattices having temporal extent of six and spatial extents of
twelve and eighteen, we find that the theory with 2 massless staggered quark
flavors has a second order finite temperature phase transition. The critical
exponents $\beta_{mag}$, $\delta$ and $\nu$ are measured and favour tricritical
behaviour over that expected by universality arguments. The pion screening mass
is consistent with zero below the transition, but is degenerate with the
nonzero $\sigma(f_0)$ mass above the transition, indicating the restoration of
chiral symmetry.

</DOC>
<DOC>
<DOCNO> 151343 </DOCNO>
SL_q(3) Fields


  The q-field theories are constructed by substituting quantum groups for the
usual Lie groups. In earlier papers this construction was carried out for the
quantum group SU_q(2). Here the investigation is extended to SL_q(3). The
resulting theory describes two sectors, one sector lying close to the standard
theory and accessible by perturbation theory, while the second sector describes
particles that should be difficult to detect and become invisible in the q=1
limit. In this note we discuss these hypothetical particles: three quark-like
spinor particles coupled to three gluon-like vector particles.

</DOC>
<DOC>
<DOCNO> 8142 </DOCNO>
Computer simulation of uniformly heated granular fluids


  Direct Monte Carlo simulations of the Enskog-Boltzmann equation for a
spatially uniform system of smooth inelastic spheres are performed. In order to
reach a steady state, the particles are assumed to be under the action of an
external driving force which does work to compensate for the collisional loss
of energy. Three different types of external driving are considered: (a) a
stochastic force, (b) a deterministic force proportional to the particle
velocity and (c) a deterministic force parallel to the particle velocity but
constant in magnitude. The Enskog-Boltzmann equation in case (b) is fully
equivalent to that of the homogeneous cooling state (where the thermal velocity
monotonically decreases with time) when expressed in terms of the particle
velocity relative to the thermal velocity. Comparison of the simulation results
for the fourth cumulant and the high energy tail with theoretical predictions
derived in cases (a) and (b) [T. P. C. van Noije and M. H. Ernst, Gran. Matt.
1, 57 (1998)] shows a good agreement. In contrast to these two cases, the
deviation from the Maxwell-Boltzmann distribution is not well represented by
Sonine polynomials in case (c), even for low dissipation. In addition, the high
energy tail exhibits an underpopulation effect in this case.

</DOC>
<DOC>
<DOCNO> 122599 </DOCNO>
Surface photometry of NGC 3077


  We present surface photometry of the irregular galaxy NGC 3077 using two data
sets: photographic plates and CCD images. Isophotal contours, luminosity and
colour distributions as well as position angle and ellipticity curves show that
NGC 3077 is similar to an elliptical galaxy in the outer regions with a
disturbed blue centre. The outer isophotes 22-25 mag/arcsec^2 are approximately
centred on the dynamical centre, the inner ones are disturbed by the dominant
contribution of a reddened young population.

</DOC>
<DOC>
<DOCNO> 122412 </DOCNO>
Foregrounds in the BOOMERANG-LDB data: a preliminary rms analysis


  We present a preliminary analysis of the BOOMERanG LDB maps, focused on
foregrounds. BOOMERanG detects dust emission at moderately low galactic
latitudes ($b > -20^o$) in bands centered at 90, 150, 240, 410 GHz. At higher
Galactic latitudes, we use the BOOMERanG data to set conservative upper limits
on the level of contamination at 90 and 150 GHz. We find that the mean square
signal correlated with the IRAS/DIRBE dust template is less than 3% of the mean
square signal due to CMB anisotropy.

</DOC>
<DOC>
<DOCNO> 174443 </DOCNO>
Near-threshold eta production in the p d -> p d eta reaction


  The total cross section of the p d -> p d eta reaction has been measured at
two energies near threshold by detecting the final proton and deuteron in a
magneti spectrometer. The values are somewhat larger than expected on the basis
of two simple theoretical estimates.

</DOC>
<DOC>
<DOCNO> 7973 </DOCNO>
Numerical Solution of the Two-Dimensional Gross-Pitaevskii Equation for


  We present a numerical scheme for solving the time-independent nonlinear
Gross-Pitaevskii equation in two dimensions describing the Bose-Einstein
condensate of trapped interacting neutral atoms at zero temperature. The trap
potential is taken to be of the harmonic-oscillator type and the interaction
both attractive and repulsive. The Gross-Pitaevskii equation is numerically
integrated consistent with the correct boundary conditions at the origin and in
the asymptotic region. Rapid convergence is obtained in all cases studied. In
the attractive case there is a limit to the maximum number of atoms in the
condensate.

</DOC>
<DOC>
<DOCNO> 151107 </DOCNO>
The Topological Particle and Morse Theory


  Canonical BRST quantization of the topological particle defined by a Morse
function h is described. Stochastic calculus, using Brownian paths which
implement the WKB method in a new way providing rigorous tunnelling results
even in curved space, is used to give an explicit and simple expression for the
matrix elements of the evolution operator for the BRST Hamiltonian. These
matrix elements lead to a representation of the manifold cohomology in terms of
critical points of h along lines developed by Witten.

</DOC>
<DOC>
<DOCNO> 122387 </DOCNO>
Primordial Star Formation under Far-ultraviolet radiation


  Thermal and chemical evolution of primordial gas clouds irradiated with
far-ultraviolet (FUV; < 13.6 eV) radiation is investigated. In clouds
irradiated by intense FUV radiation, sufficient hydrogen molecules to be
important for cooling are never formed. However, even without molecular
hydrogen, if the clouds are massive enough, they start collapsing via atomic
hydrogen line cooling. Such clouds continue to collapse almost isothermally
owing to successive cooling by H^{-} free-bound emission up to the number
density of 10^{16} cm^{-3}. Inside the clouds, the Jeans mass eventually falls
well below a solar mass. This indicates that hydrogen molecules are dispensable
for low-mass primordial star formation, provided fragmentation of the clouds
occurs at sufficiently high density.

</DOC>
<DOC>
<DOCNO> 152468 </DOCNO>
Pointlike Hopf defects in Abelian projections


  We present a new kind of defect in Abelian Projections, stemming from
pointlike zeros of second order. The corresponding topological quantity is the
Hopf invariant pi_3(S^2) (rather than the winding number pi_2(S^2) for magnetic
monopoles). We give a visualisation of this quantity and discuss the simplest
non-trivial example, the Hopf map. Such defects occur in the Laplacian Abelian
gauge in a non-trivial instanton sector. For general Abelian projections we
show how an ensemble of Hopf defects accounts for the instanton number.

</DOC>
<DOC>
<DOCNO> 116497 </DOCNO>
The rf control and detection system for PACO the parametric converter


  In this technical note the rf control and detection system for a detector of
small harmonic displacements based on two coupled microwave cavities (PACO) is
presented. The basic idea underlying this detector is the principle of
parametric power conversion between two resonant modes of the system,
stimulated by the (small) harmonic modulation of one system parameter. In this
experiment we change the cavity length applying an harmonic voltage to a
piezo-electric crystal. The system can achieve a great sensitivity to small
harmonic displacements and can be an interesting candidate for the detection of
small, mechanically coupled, interactions (e.g. high frequency gravitational
waves).

</DOC>
<DOC>
<DOCNO> 80656 </DOCNO>
Spontaneous Breakdown of Lorentz Invariance in IIB Matrix Model


  We study the IIB matrix model, which is conjectured to be a nonperturbative
definition of superstring theory, by introducing an integer deformation
parameter `nu' which couples to the imaginary part of the effective action
induced by fermions. The deformed IIB matrix model continues to be well-defined
for arbitrary `nu', and it preserves gauge invariance, Lorentz invariance, and
the cluster property. We study the model at `nu' = infinity using a
saddle-point analysis, and show that ten-dimensional Lorentz invariance is
spontaneously broken at least down to an eight-dimensional one. We argue that
it is likely that the remaining eight-dimensional Lorentz invariance is further
broken, which can be checked by integrating over the saddle-point
configurations using standard Monte Carlo simulation.

</DOC>
<DOC>
<DOCNO> 151154 </DOCNO>
Anomalous Scale Dimensions from Timelike Braiding


  Using the previously gained insight about the particle/field relation in
conformal quantum field theories which required interactions to be related to
the existence of particle-like states associated with fields of anomalous
scaling dimensions, we set out to construct a classification theory for the
spectra of anomalous dimensions. Starting from the old observations on
conformal superselection sectors related to the anomalous dimensions via the
phases which appear in the spectral decomposition of the center of the
conformal covering group $Z(\widetilde{SO(d,2)}),$ we explore the possibility
of a timelike braiding structure consistent with the timelike ordering which
refines and explains the central decomposition. We regard this as a preparatory
step in a new construction attempt of interacting conformal quantum field
theories in D=4 spacetime dimensions. Other ideas of constructions based on the
$AdS_{5}$-$CQFT_{4}$ or the perturbative SYM approach in their relation to the
present idea are briefly mentioned.

</DOC>
<DOC>
<DOCNO> 178676 </DOCNO>
Spin observables for pion production from pd collisions


  We have calculated the proton analyzing power A_{y0} of the pion-production
reaction from pd collisions for one energy close to threshold and for another
in the region of the $\Delta$-resonance. A fair reproduction of the
experimental data could be obtained in both cases with a model which includes
isoscalar and isovector $\pi N$ rescatterings in s waves, as well as the p-wave
rescattering mechanisms mediated by the $\pi NN$ and $\pi N \Delta$ vertices.
For the analyzing power at threshold we found that the initial-state
interaction (ISI) is also quite important.

</DOC>
<DOC>
<DOCNO> 118392 </DOCNO>
Synchrotron and Compton Components and their Variability in BL Lac


  BL Lacertae objects are extreme extragalactic sources characterized by the
emission of strong and rapidly variable nonthermal radiation over the entire
electromagnetic spectrum. Synchrotron emission followed by inverse Compton
scattering in a relativistic beaming scenario is generally thought to be the
mechanism powering these objects. ...

</DOC>
<DOC>
<DOCNO> 170092 </DOCNO>
A two-qubit algorithm involving quantum entanglement


  The phenomenon of quantum entanglement is fundamental to the implementation
of quantum computation, and requires at least two qubits for its demonstration.
However, both Deutsch algorithm and Grover's search algorithm for two bits do
not use entanglement. We develop a Deutsch-like problem, where we consider all
possible binary functions for two bit inputs and distinguish their even or odd
nature. The quantum algorithm to solve this problem requires entanglement at
the level of two qubits. The final solution suggests that an NMR implementation
of the problem would lead to interesting results.

</DOC>
<DOC>
<DOCNO> 80788 </DOCNO>
Meson Correlators in Finite Temperature Lattice QCD


  We analyze temporal and spatial meson correlators in quenched lattice QCD at
T>0. Below T_c we observe little change in the meson properties as compared
with T=0. Above T_c we observe new features: chiral symmetry restoration and
signals of plasma formation, but also indication of persisting mesonic
(metastable) states and different temporal and spatial masses in the mesonic
channels. This suggests a complex picture of QGP in the region 1 - 1.5 T_c.

</DOC>
<DOC>
<DOCNO> 85050 </DOCNO>
Generalized Second Law of Black Hole Thermodynamics and Quantum


  We propose a quantum version of a gedanken experiment which supports the
generalized second law of black hole thermodynamics. A quantum measurement of
particles in the region outside of the event horizon decreases the entropy of
the outside matter due to the entanglement of the inside and outside particle
states. This decrease is compensated, however, by the increase in the detector
entropy. If the detector is conditionally dropped into the black hole depending
on the experimental outcome, the decrease of the matter entropy is more than
compensated by the increase of the black hole entropy via the increase of the
black hole mass which is ultimately attributed to the work done by the
measurement.

</DOC>
<DOC>
<DOCNO> 72327 </DOCNO>
Quintessence and the Separation of CMB Peaks


  We propose that it should be possible to use the CMB to discriminate between
dark energy models with different equations of state, including distinguishing
a cosmological constant from many models of quintessence. The separation of
peaks in the CMB anisotropies can be parametrised by three quantities: the
amount of quintessence today, the amount at last scattering, and the averaged
equation of state of quintessence. In particular, we show that the CMB peaks
can be used to measure the amount of dark energy present before last
scattering.

</DOC>
<DOC>
<DOCNO> 122999 </DOCNO>
Chandra Discovers a Very High Density X-ray Plasma on the O-Star Zeta


  We report on a Chandra line spectrum observation of the O supergiant, Zeta
Orionis (O9.7 Ib). A 73.4 ks HETGS observation shows a wide range of ionization
stages and line strengths over the wavelength range of 5 to 26 A. The observed
emission lines indicate a range in temperature of 2 to 10 MK which is
consistent with earlier X-ray observations of Zeta Ori. Many lines are
spectrally resolved showing Doppler broadening of 900 +/- 200 km/s. The
observed He-like ions (O VII, Ne IX, Mg XI, and Si XIII) provide information
about the spatial distribution of the X-ray emission. Although the observations
support a wind distribution of X-ray sources, we find three conflicting
results. First, line diagnostics for SIXIII indicate that this line emission
forms very close to the stellar surface, where the density is of order 10^{12}
cm^{-3}, but the velocity there is too small to produce the shock jump required
for the observed ionization level. Second, the strong X-ray line profiles are
symmetric and do not show any evidence of Doppler blue-shifted line centroids
which are expected to accompany an outwardly moving source in a high density
wind. Third, the observed velocity dispersions do not appear to correlate with
the associated X-ray source radii velocities, contrary to expectations of wind
distributed source models. A composite source model involving wind shocks and
some magnetic confinement of turbulent hot plasma in a highly non-symmetric
wind, appears to be needed to explain the line diagnostic anomalies.

</DOC>
<DOC>
<DOCNO> 80641 </DOCNO>
Static potentials and glueball masses from QCD simulations with Wilson


  We calculate glueball and torelon masses as well as the lowest lying hybrid
potential in addition to the static ground state potential in lattice
simulations of QCD with two flavours of dynamical Wilson fermions. The results
are obtained on lattices with $16^3\times 32$ and $24^3\times 40$ sites at
$\beta=5.6$, corresponding to a lattice spacing, $a^{-1}=2.65^{+5}_{-8}$ GeV,
as determined from the Sommer force radius, at physical sea quark mass. The
range spanned in the present study of five different quark masses is reflected
in the ratios, $0.83\geq m_{\pi}/m_{\rho}\geq 0.57$.

</DOC>
<DOC>
<DOCNO> 122063 </DOCNO>
Quasar luminosity and twin effects induced by filamentary and planar


  We consider filamentary and planar large scale structures as possible
refraction channels for electromagnetic radiation coming from cosmological
structures. By this hypothesis, it is possible to explain the quasar luminosity
distribution and, in particular, the presence of "twin" and "brother" objects.
Method and details of simulation are given.

</DOC>
<DOC>
<DOCNO> 121925 </DOCNO>
The morphology of extremely red objects


  We present a quantitative study of the morphology of 41 Extremely Red Objects
(EROs). The analysis is based on deep otical and near-infrared images from the
Hubble Space Telescope public archive, and performed by fitting to each galaxy
image a PSF-convolved bi-dimensional model brightness distribution. Relying
both on the visual inspection of the data and on the results of the fitting
procedure, we are able to determine the fraction of irregular and/or
interacting EROs, and to identify those that more closely resemble local
ellipticals. To the former class, whose members are probably high-redshift
dusty starburst, belongs about 15% of the whole sample, whereas the
elliptical-like objects are between 50 and 80% of the total. A few galaxies,
although characterized by a compact morphology, are best fitted by an
exponential distribution, more typical of local spirals. Our data also suggest
that irregular EROs are found predominantly in the field, and that - on average
- they tend to be characterized by the reddest colors. Finally, we plot the
rest-frame Kormendy Relation ($\mu_e$ vs. $R_e$) for a sample of 6 EROs with
spectroscopic redshifts ($z \sim 1.3$), and estimate its evolution with respect
to the local relation.

</DOC>
<DOC>
<DOCNO> 178426 </DOCNO>
Aspects of thermal and chemical equilibration of hadronic matter


  We study thermal and chemical equilibration in 'infinite' hadron matter as
well as in finite size relativistic nucleus-nucleus collisions using a BUU
cascade transport model that contains resonance and string degrees-of-freedom.
The 'infinite' hadron matter is simulated within a cubic box with periodic
boundary conditions. The various equilibration times depend on baryon density
and energy density and are much shorter for particles consisting of light
quarks then for particles including strangeness. For kaons and antikaons the
chemical equilibration time is found to be larger than $\simeq$ 40 fm/c for all
baryon and energy densities considered. The inclusion of continuum excitations,
i.e. hadron 'strings', leads to a limiting temperature of $T_s\simeq$ 150 MeV.
We, furthermore, study the expansion of a hadronic fireball after
equilibration. The slope parameters of the particles after expansion increase
with their mass; the pions leave the fireball much faster then nucleons and
accelerate subsequently heavier hadrons by rescattering ('pion wind'). If the
system before expansion is close to the limiting temperature $T_s$, the slope
parameters for all particles after expansion practically do not depend on
(initial) energy and baryon density. Finally, the equilibration in relativistic
nucleus-nucleus collision is considered. Since the reaction time here is much
shorter than the equilibration time for strangeness, a chemical equilibrium of
strange particles in heavy-ion collisions is not supported by our transport
calculations. However, the various particle spectra can approximately be
described within the blast model.

</DOC>
<DOC>
<DOCNO> 85090 </DOCNO>
Post-Riemannian Merger of Yang-Mills Interactions with Gravity


  We show that a post-Riemannian spacetime can accommodate an internal symmetry
structure of the Yang-Mills prototype in such a way that the internal symmetry
becomes an integral part of the spacetime itself. The construction encrusts the
internal degrees of freedom in spacetime in a manner that merges the gauging of
these degrees of freedom with the frame geometrical gauges of spacetime. In
particular, we prove that the three spacetime structural identities, which now
become ``contaminated'' by internal degrees of freedom, remain invariant with
respect to internal gauge transformations. In a Weyl Cartan spacetime, the
theory regains the original form of Einstein's equations, in which gauge field
sources on the r.h.s. determine on the l.h.s the geometry of spacetime and the
fields it induces. In the more general case we identify new contributions of
weak magnitude in the interaction between the Yang-Mills field and gravity. The
merger of spacetime with internal degrees of freedom which we propose here is
not constrained by the usual Coleman-Mandula considerations.

</DOC>
<DOC>
<DOCNO> 9154 </DOCNO>
Critical Ruptures


  The fracture of materials is a catastrophic phenomenon of considerable
technological and scientific importance. Here, we analysed experiments designed
for industrial applications in order to test the concept that, in heterogeneous
materials such as fiber composites, rocks, concrete under compression and
materials with large distributed residual stresses, rupture is a genuine
critical point, i.e. the culmination of a self-organization of damage and
cracking characterized by power law signatures. Specifically, we analyse the
acoustic emissions recorded during the pressurisation of spherical tanks of
kevlar or carbon fibers pre-impregnated in a resin matrix wrapped up around a
thin metallic liner (steel or titanium) fabricated and instrumented by
A\'erospatiale-Matra Inc. These experiments are performed as part of a routine
industrial procedure which tests the quality of the tanks prior to shipment and
varies in nature. We find that the seven acoustic emission recordings of seven
pressure tanks which was brought to rupture exhibit clear acceleration in
agreement with a power law ``divergence'' expected from the critical point
theory. In addition, we find strong evidence of log-periodic corrections that
quantify the intermittent succession of accelerating bursts and quiescent
phases of the acoustic emissions on the approach to rupture. An improved model
accounting for the cross-over from the non-critical to the critical region
close to the rupture point exhibits interesting predictive potential.

</DOC>
<DOC>
<DOCNO> 10078 </DOCNO>
Impurity Effects on Quantum Depinning of Commensurate Charge Density


  We investigate quantum depinning of the one-dimensional (1D) commensurate
charge-density wave (CDW) in the presence of one impurity theoretically.
Quantum tunneling rate below but close to the threshold field is calculated at
absolute zero temperature by use of the phase Hamiltonian within the WKB
approximation. We show that the impurity can induce localized fluctuation and
enhance the quantum depinning. The electric field dependence of the tunneling
rate in the presence of the impurity is different from that in its absence.

</DOC>
<DOC>
<DOCNO> 120042 </DOCNO>
Photometric catalog of nearby globular clusters (II)


  In this paper we present the second and final part of a large and
photometrically homogeneous CCD color-magnitude diagram (CMD) data base,
comprising 52 nearby Galactic globular clusters (GGC) imaged in the V and I
bands.
  The catalog has been collected using only two telescopes (one for each
hemisphere). The observed clusters represent 75% of the known Galactic
globulars with (m-M)_v <= 16.15 mag, cover most of the globular cluster
metallicity range (-2.2 <= [Fe/H] <= -0.4), and span Galactocentric distances
from ~1.2 to ~18.5 kpc.
  In particular, here we present the CMDs for the 13 GGCs observed in the
Northern hemisphere. The remaining 39 Southern hemisphere clusters of the
catalog have been presented in a companion paper (Rosenberg et al., 2000, A&AS
144, 5). We present the first CCD color magnitude diagram for NGC6779 (M56).
  All the CMDs extend from at least ~2 magnitudes below the turn-off (i.e.
V_lim ~22) to the tip of the red giant branch. The calibration has been done
using a large number of standard stars, and the absolute calibration is
reliable to a ~0.02 mag level in both filters.
  This catalog, because of its homogeneity, is expected to represent a useful
data base for the measurement of the main absolute and relative parameters
characterizing the CMD of GGCs.

</DOC>
<DOC>
<DOCNO> 13132 </DOCNO>
Electronic Structure of CeRhIn$_{5}$: dHvA and Energy Band Calculations


  The de Haas - van Alphen effect and energy band calculations are used to
study angular dependent extremal areas and effective masses of the Fermi
surface of the highly correlated antiferromagnetic material CeRhIn$_5$. The
agreement between experiment and theory is reasonable for the areas measured
with the field applied along the (100) axis of the tetragonal structure, but
disagree in size for the areas observed for the field applied along the (001)
axis where the antiferromagnetic spin alignment is occurring. Detailed
comparisons between experiment and theory are given.

</DOC>
<DOC>
<DOCNO> 170436 </DOCNO>
Equally-distant partially-entangled alphabet states for quantum channels


  Each Bell state has the property that by performing just local operations on
one qubit, the complete Bell basis can be generated. That is, states generated
by local operations are totally distinguishable. This remarkable property is
due to maximal quantum entanglement between the two particles. We present a set
of local unitary transformations that generate out of partially entangled
two-qubit state a set of four maximally distinguishable states that are
mutually equally distant. We discuss quantum dense coding based on these
alphabet states.

</DOC>
<DOC>
<DOCNO> 7784 </DOCNO>
Effective Surface Impedance of Polycrystals Under Conditions of


  The effective impedance of strongly anisotropic polycrystals has been
investigated under the conditions of extremely anomalous skin effect. We were
interested in finding out how the value of the effective impedance depends on
the geometry of the Fermi surface of a single crystal grain. The previously
obtained nonperturbative solution based on the application of the impedance
(the Leontovich) boundary conditons was used to calculate the effective
impedance of a polycrystalline metal. When the Fermi surface is a surface of
revolution, the expression for the effective impedance is rather simple. Some
model Fermi surfaces were examined. In the vicinity of the electronic
topological transition the singularities of the effective impedance related to
the change of the topology of the Fermi surface were calculated. Our results
show that though a polycrystal is an isotropic medium in average, it is not
sufficient to consider it as a metal with an effective spherical Fermi surface,
since this can lead to the loss of some characteristic features of extremely
anomalous skin effect in polycrystals.

</DOC>
<DOC>
<DOCNO> 12504 </DOCNO>
Surface-state electron dynamics in noble metals


  Theoretical investigations of surface-state electron dynamics in noble metals
are reported. The dynamically screened interaction is computed, within
many-body theory, by going beyond a free-electron description of the metal
surface. Calculations of the inelastic linewidth of Shockley surface-state
electrons and holes in these materials are also presented. While the linewidth
of excited holes at the surface-state band edge (${\bf k}_\parallel=0$) is
dominated by a two-dimensional decay channel, within the surface-state band
itself, our calculations indicate that major contributions to the
electron-electron interaction of surface-state electrons above the Fermi level
come from the underlying bulk electrons.

</DOC>
<DOC>
<DOCNO> 7742 </DOCNO>
Superconducting and Insulating Behavior in One-Dimensional Josephson


  Experiments on one-dimensional small capacitance Josephson Junction arrays
are described. The arrays have a junction capacitance that is much larger than
the stray capacitance of the electrodes, which we argue is important for
observation of Coulomb blockade. The Josephson energy can be tuned in situ and
an evolution from Josephson-like to Coulomb blockade behavior is observed. This
evolution can be described as a superconducting to insulating, quantum phase
transition. In the Coulomb blockade state, hysteretic current-voltage
characteristics are described by a dynamic model which is dual to the
resistively shunted junction model of classical Josephson junctions.

</DOC>
<DOC>
<DOCNO> 11075 </DOCNO>
Effects of a nanoscopic filler on the structure and dynamics of a


  We perform molecular dynamics simulations of an idealized polymer melt
surrounding a nanoscopic filler particle to probe the effects of a filler on
the local melt structure and dynamics. We show that the glass transition
temperature $T_g$ of the melt can be shifted to either higher or lower
temperatures by appropriately tuning the interactions between polymer and
filler. A gradual change of the polymer dynamics approaching the filler surface
causes the change in the glass transition. We also find that while the bulk
structure of the polymers changes little, the polymers close to the surface
tend to be elongated and flattened, independent of the type of interaction we
study. Consequently, the dynamics appear strongly influenced by the
interactions, while the melt structure is only altered by the geometric
constraints imposed by the presence of the filler. Our findings show a strong
similarity to those obtained for ultra-thin polymer films (thickness $\lesssim
100$ nm) suggesting that both ultra-thin films and filled-polymer systems might
be understood in the same context.

</DOC>
<DOC>
<DOCNO> 8659 </DOCNO>
Time discretization of functional integrals


  Numerical evaluation of functional integrals usually involves a finite
(L-slice) discretization of the imaginary-time axis. In the auxiliary-field
method, the L-slice approximant to the density matrix can be evaluated as a
function of inverse temperature at any finite L as
$\rho_L(\beta)=[\rho_1(\beta/L)]^L$, if the density matrix $\rho_1(\beta)$ in
the static approximation is known. We investigate the convergence of the
partition function $Z_L(\beta)=Tr\rho_L(\beta)$, the internal energy and the
density of states $g_L(E)$ (the inverse Laplace transform of $Z_L$), as
$L\to\infty$. For the simple harmonic oscillator, $g_L(E)$ is a normalized
truncated Fourier series for the exact density of states. When the
auxiliary-field approach is applied to spin systems, approximants to the
density of states and heat capacity can be negative. Approximants to the
density matrix for a spin-1/2 dimer are found in closed form for all L by
appending a self-interaction to the divergent Gaussian integral and
analytically continuing to zero self-interaction. Because of this continuation,
the coefficient of the singlet projector in the approximate density matrix can
be negative. For a spin dimer, $Z_L$ is an even function of the coupling
constant for L<3: ferromagnetic and antiferromagnetic coupling can be
distinguished only for $L\ge 3$, where a Berry phase appears in the functional
integral. At any non-zero temperature, the exact partition function is
recovered as $L\to\infty$.

</DOC>
<DOC>
<DOCNO> 120736 </DOCNO>
A spectroscopic survey for strong galaxy-galaxy lenses


  We present a spectroscopic survey for strong galaxy-galaxy lenses. Exploiting
optimal sight-lines to massive, bulge-dominated galaxies at redshifts $z \sim
0.4$ with wide-field, multifibre spectroscopy, we anticipate the detection of
10-20 lensed Lyman-$\alpha$ emitting galaxies at redshifts $z \simgreat 3$ from
a sample of 2000 deflectors. Initial spectroscopic observations are described
and the prospects for constraining the emission-line luminosity function of the
Lyman-$\alpha$ emitting population are outlined.

</DOC>
<DOC>
<DOCNO> 67897 </DOCNO>
Cosmological Expansion in the Randall-Sundrum Warped Compactification


  The cosmology of a brane-universe embedded in a higher dimensional bulk
spacetime presents some peculiarities not seen in ordinary (3+1) dimensional
gravity. I summarize the current understanding, with emphasis on the suggestion
by Randall and Sundrum that the bulk is 5-D anti-deSitter space, leading to a
solution of the weak scale hierarchy problem.

</DOC>
<DOC>
<DOCNO> 100315 </DOCNO>
The Roelcke compactification of groups of homeomorphisms


  Let X be a zero-dimensional compact space such that all non-empty clopen
subsets of X are homeomorphic to each other, and let H(X) be the group of all
self-homeomorphisms of X with the compact-open topology. We prove that the
Roelcke compactification of H(X) can be identified with the semigroup of all
closed relations on X whose domain and range are equal to X. We use this to
prove that the group H(X) is topologically simple and minimal, in the sense
that it does not admit a strictly coarser Hausdorff group topology.

</DOC>
<DOC>
<DOCNO> 120201 </DOCNO>
The Dark and Luminous Matter coupling in the formation of spheroids: a


  Using N-body/hydrodynamical simulations which include prescriptions for Star
Formation, Feed-Back and Chemical Evolution, we explore the interaction between
baryons and Dark Matter at galactic scale. The N-body simulations are performed
using a Tree-SPH code that follows the evolution of individual DM halos inside
which stars form from cooling gas, and evolve delivering in the interstellar
medium mass, metals, and energy. We examine the formation and evolution of a
giant and a dwarf elliptical galaxy of total mass 10^12 and 10^9 solar masses,
respectively. Starting from an initial density profile like the universal
Navarro profile in the inner region, baryons sink towards the center due to
cooling energy losses. At the end of the collapse, the innermost part (1/20 of
the halo size) of the galaxy is baryon-dominated, whereas the outer regions are
DM dominated. The Star Formation proceeds at much faster speed in the giant
galaxy where a spheroid of 8 \times 10^10 solar masses is formed in 2 Gyr, with
respect to the dwarf galaxy where the spheroid of 2 \times 10^7 solar masses is
formed in 4 Gyr. For the two objects the final distribution of stars is well
fitted by a Hernquist profile with effective radii of r_e = 30 kpc, and 2.8
kpc, respectively. The dark-to-luminous tarnsition radius r_IBD occurs roughly
at 1 r_e, as in real ellipticals. The DM halo density evolution is
non-adiabatic and does not lead to a core radius.

</DOC>
<DOC>
<DOCNO> 150570 </DOCNO>
Bounds on curved domain walls in 5d gravity


  We discuss maximally symmetric curved deformations of the flat domain wall
solutions of five-dimensional dilaton gravity that appeared in a recent
approach to the cosmological constant problem. By analyzing the bulk field
configurations and the boundary conditions at a four-dimensional maximally
symmetric curved domain wall, we obtain constraints on such solutions. For a
special dilaton coupling to the brane tension that appeared in recent works, we
find no curved deformations, confirming and extending slightly a result of
Arkani-Hamed et al which was argued using a $Z_2$-symmetry of the solution. For
more general dilaton-dependent brane tension, we find that the curvature is
bounded by the Kaluza-Klein scale in the fifth dimension.

</DOC>
<DOC>
<DOCNO> 170401 </DOCNO>
Quantum-Classical Correspondence of Dynamical Observables, Quantization


  We raise the problem of constructing quantum observables that have classical
counterparts without quantization. Specifically we seek to define and motivate
a solution to the quantum-classical correspondence problem independent from
quantization and discuss the general insufficiency of prescriptive
quantization, particularly the Weyl quantization. We demonstrate our points by
constructing time of arrival operators without quantization and from these
recover their classical counterparts.

</DOC>
<DOC>
<DOCNO> 118149 </DOCNO>
HST Images of Stephan's Quintet: Star Cluster Candidates in a Compact


  We present HST WFPC2 images of Stephan's Quintet which encompass three
interacting galaxies and their associated tidal features. These deep,
three-color (B, V, I) images indicate recent, massive stellar system formation
in various regions within the compact group environment. We have identified
star cluster candidates (SCC) both within the interacting galaxies and in the
tidal debris. We compare the SCC colors with stellar population synthesis
models in order to constrain cluster ages, and compare the pattern of formation
of SCC in different regions to the inferred dynamical history of the group.

</DOC>
<DOC>
<DOCNO> 121226 </DOCNO>
Electric Charge and Magnetic Flux on Rotating Black Holes in a


  The electric charge on rotating black holes is calculated to be ~ BJ in the
force-free configuration of Ghosh (2000), with a horizon flux of ~ BM^2. This
charge is gravitationally weak for B ~ 10^{15} G, so that the Kerr metric
applies. Being similar to the electric charge of a magnetar, both electric
charge and magnetic flux should be, in sign and order of magnitude, continuous
during stellar collapse into a black hole. Extraction of the rotational energy
from newly formed black holes may proceed by interaction with the magnetic
field. Keywords:black hole physics --magnetic fields

</DOC>
<DOC>
<DOCNO> 117526 </DOCNO>
The redshift evolution of bias and baryonic matter distribution


  We study the distribution of baryonic and luminous matter within the
framework of a hierarchical scenario. Using an analytical model for structure
formation which has already been checked against observations for galaxies,
Lyman-$\alpha$ clouds, clusters and reionization processes, we present its
predictions for the bias of these objects. We describe its dependence on the
luminosity (for galaxies or quasars) or the column density (for Lyman-$\alpha$
absorbers) of the considered objects. We also study its redshift evolution,
which can exhibit an intricate behaviour. These astrophysical objects do not
trace the dark matter density field, the Lyman-$\alpha$ forest clouds being
undercorrelated and the bright galaxies overcorrelated, while the intermediate
class of Lyman-limit systems is seen to sample the matter field quite well.
 We also present the distribution of baryonic matter over these various
objects. We show that light does not trace baryonic mass, since bright galaxies
which contain most of the stars only form a small fraction of the mass
associated with virialized and cooled halos. We consider two cosmologies: a
critical density universe and an open universe. In both cases, our results
agree with observations and show that hierarchical scenarios provide a good
model for structure formation and can describe a wide range of objects which
spans at least the seven orders of magnitude in mass for which data exist. More
detailed observations, in particular of the clustering evolution of galaxies,
will constrain the astrophysical models involved.

</DOC>
<DOC>
<DOCNO> 11771 </DOCNO>
Anomalous Features in Surface Impedance of Y-Ba-Cu-O Thin Films:


  Two high-quality Y-Ba-Cu-O thin films on MgO substrates have been
investigated using the coplanar resonator technique at 8 and 16 GHz. Both films
exhibit an anomalous decrease in their surface impedance, Zs as a function of
microwave field, Hrf. In zero dc field, Hrf-dependences of Rs and Xs for both
the samples are uncorrelated, and only one of the quantities, Rs or Xs,
displays anomalous behavior. Here, application of relatively weak (~5 mT) dc
magnetic fields, Hdc can produce a correlated decrease of Rs(Hrf) and Xs(Hrf).
The dependences of Zs on Hdc in both low and high microwave power regimes were
found to be non-monotonic. The frequency dependence of Rs ~ fn, 1.7<n<2.5,
remained the same upon the transition from low to high microwave power ranges.
The consequences of the reported findings for microwave device applications are
briefly discussed

</DOC>
<DOC>
<DOCNO> 151102 </DOCNO>
On The BRST Formulation of Diffeomorphism Invariant 4D Quantum Gravity


  In this note we give some remarks on the BRST formulation of a renormalizable
and diffemorphism invariant 4D quantum gravity recently proposed by the author,
which satisfies the integrability condition by Riegard, Fradkin and Tseytlin at
the 2-loop level. Diffeomorphism invariance requires an addition of the
Wess-Zumino action, from which the Weyl action can be induced by expanding
around a vacuum expectation value of the conformal mode. This fact suggests the
theory has in itself a mechanism to remove extra negative-metric states
dynamically.

</DOC>
<DOC>
<DOCNO> 70594 </DOCNO>
Fermion transmutation - a renormalization effect in gauge theory


  A new category of phenomena is predicted in which fermions of different
flavours can transmute into one another, for example $e \to \mu$ or $e \to
\tau$, as a consequence of the `rotating' mass matrix due to renormalization.
As examples, calculations will be presented for various such processes. Some of
these could be accessible to experiments in the near future.

</DOC>
<DOC>
<DOCNO> 170045 </DOCNO>
Bell Measurements and Observables


  A general matrix approach to study entangled states is presented, based on
operator completeness relations. Bases of unitary operators are considered,
with focus on irreducible representations of groups. Bell measurements for
teleportation are considered, and robustness of teleportation to various kinds
of non idealities is shown.

</DOC>
<DOC>
<DOCNO> 80623 </DOCNO>
The CP-PACS Project and Lattice QCD Results


  The aim of the CP-PACS project was to develop a massively parallel computer
for performing numerical research in computational physics with primary
emphasis on lattice QCD. The CP-PACS computer with a peak speed of 614 GFLOPS
with 2048 processors was completed in September 1996, and has been in full
operation since October 1996. We present an overview of the CP-PACS project and
describe characteristics of the CP-PACS computer. The CP-PACS has been mainly
used for hadron spectroscopy studies in lattice QCD. Main results in lattice
QCD simulations are given.

</DOC>
<DOC>
<DOCNO> 9977 </DOCNO>
Vortex dynamics of Bi2212 studied by the high magnetic transverse field


  This paper has been withdrawn by the authors to correct SERIOUS errors in the
data analysis, also this manuscript needs to be restructured and reorganized.

</DOC>
<DOC>
<DOCNO> 119334 </DOCNO>
ISOPHOT CIRB project: FIR source counts at 90, 150 and 180 um


  Far-infrared maps obtained with ISOPHOT have been searched for point-like
sources. The majority of the 55 sources is believed to be extragalactic and in
most cases no previously known sources can be associated with them. Based on
the far-infrared spectral energy distributions it is likely that
dust-enshrouded, distant galaxies form a significant fraction of the sources.
  We estimate the number densities of extragalactic sources at 90, 150 and 180
um wavelengths and at flux density levels down to 100 mJy. The counts are
compared with models of galaxy evolution. The counts exceed the predictions of
current models, even those with strong evolution, and no-evolution models are
rejected at a high confidence level.
  Comparison with recent results from COBE mission indicates that at 90 um the
detected sources correspond to over 20% of the extragalactic background light.
At longer wavelengths the corresponding fraction is 10%.

</DOC>
<DOC>
<DOCNO> 13122 </DOCNO>
Thermoelectric Effects in S-N-S Weak Links with Heavy Fermions as The


  It is shown that S-N-S weak links with an heavy-fermion metal as the weak
link (N) can be useful thermosensors. This property is due to the large
thermopower of heavy-fermion metals which is of the order 10^(-6) V/K. The
longitudinal sound can also generate voltage oscillation due to the large
Grueneisen parameter, $\Omega_{hf}\sim 10^{2}$, in heavy-fermions. Similar
effects are expected with other Kondo systems as the weak link.

</DOC>
<DOC>
<DOCNO> 69675 </DOCNO>
Hybrid Parallel Computation of Integration in GRACE


  With an integrated software package {\tt GRACE}, it is possible to generate
Feynman diagrams, calculate the total cross section and generate physics events
automatically. We outline the hybrid method of parallel computation of the
multi-dimensional integration of {\tt GRACE}. We used {\tt MPI} (Message
Passing Interface) as the parallel library and, to improve the performance we
embedded the mechanism of the dynamic load balancing. The reduction rate of the
practical execution time was studied.

</DOC>
<DOC>
<DOCNO> 70031 </DOCNO>
Signatures of Quark-Gluon Plasma Phase Transition in High-Energy Nuclear


  In high-energy nuclear collisions, the new phase of the quark-gluon plasma is
indicated by an anomalous increase in pressure, an excess of direct photon
production, an excess of strangeness production, and an anomalous J/psi
suppression. We review these signatures and discuss how recent high-energy
heavy-ion experiments at CERN are consistent with the production of the
quark-gluon plasma in high-energy Pb+Pb collisions.

</DOC>
<DOC>
<DOCNO> 69136 </DOCNO>
Semi-inclusive hadron-hadron transverse spin asymmetries and their


  We discuss a possible explanation of the 25 year old mystery of the large
transverse spin asymmetries found in many semi-inclusive hadron-hadron
reactions. We obtain the first reliable information about the transverse
polarized quark densities Delta_T q(x) and we find surprising implications for
the usual, longitudinal, polarized DIS. The plan of the presentation is as
follows: 1) A brief reminder about the internal structure of the nucleon. 2)
The transverse asymmetries. 3) Why it is so difficult to explain the
asymmetries. 4) Failure and then success using a new soft mechanism. 5)
implications for polarized DIS.

</DOC>
<DOC>
<DOCNO> 10825 </DOCNO>
Local optical spectroscopy of semiconductor nanostructures in the linear


  We present a theoretical approach to calculate the {\it local} absorption
spectrum of excitons confined in a semiconductor nanostructure. Using the
density-matrix formalism, we derive a microscopic expression for the non-local
susceptibility, both in the linear and non-linear regimes, which includes a
three-dimensional description of electronic quantum states and their Coulomb
interaction. The knowledge of the non-local susceptibility allows us to
calculate a properly defined local absorbed power, that depends on the
electro-magnetic field distribution. We report on explicit calculations of the
local linear response of excitons confined in single and coupled T-shaped
quantum wires with realistic geometry and composition. We show that significant
interference effects in the interacting electron-hole wavefunction induce new
features in the space-resolved optical spectra, particularly in coupled
nanostructures. When the spatial extension of the electromagnetic field is
comparable to the exciton Bohr radius, Coulomb effects on the local spectra
must be taken into account for a correct assignment of the observed features.

</DOC>
<DOC>
<DOCNO> 150873 </DOCNO>
Hyperbolic Spaces in String and M-Theory


  We describe string-theory and $d=11$ supergravity solutions involving
symmetric spaces of constant negative curvature. Many examples of
non-supersymmetric string compactifications on hyperbolic spaces $H_r$ of
finite volume are given in terms of suitable cosets of the form $H_r/\Gamma $,
where $\Gamma $ is a discrete group. We describe in some detail the cases of
the non-compact hyperbolic spaces $F_2$ and $F_3$, representing the fundamental
regions of $H_2$ and $H_3$ under $SL(2,Z)$ and the Picard group, respectively.
By writing $AdS$ as a U(1) fibration, we obtain new solutions where
$AdS_{2p+1}$ gets untwisted by T-duality to ${\bf R}\times SU(p,1)/(SU(p)\times
U(1))$. Solutions with time-dependent dilaton field are also constructed by
starting with a solution with NS5-brane flux over $H_3$. A new class of
non-supersymmetric conformal field theories can be defined via holography.

</DOC>
<DOC>
<DOCNO> 84706 </DOCNO>
Rotating Bianchi type V dust models generalizing the k = -1 Friedmann


  The Einstein equations for one of the hypersurface-homogeneous rotating dust
models are investigated. It is a Bianchi type V model in which one of the
Killing fields is spanned on velocity and rotation (case 1.2.2.2 in the
classification scheme of the earlier papers). A first integral of the field
equations is found, and with a special value of this integral coordinate
transformations are used to eliminate two components of the metric. The k = -1
Friedmann model is shown to be contained among the solutions in the limit of
zero rotation. The field equations for the simplified metric are reduced to 3
second-order ordinary differential equations that determine 3 metric components
plus a first integral that algebraically determines the fourth component. First
derivatives of the metric components are subject to a constraint (a
second-degree polynomial with coefficients depending on the functions). It is
shown that the set does not follow from a Lagrangian of the Hilbert type. The
group of Lie point-symmetries of the set is found, it is two-dimensional
noncommutative. Finally, a method of searching for first integrals (for sets of
differential equations) that are polynomials of degree 1 or 2 in the first
derivatives is applied. No such first integrals exist. The method is used to
find a constraint (of degree 1 in first derivatives) that could be imposed on
the metric, but it leads to a vacuum solution, and so is of no interest for
cosmology.

</DOC>
<DOC>
<DOCNO> 13238 </DOCNO>
Edwards' measures: a thermodynamic construction for dense granular media


  We present numerical support for the hypothesis that macroscopic observables
of dense granular media can be evaluated from averages over typical blocked
configurations: we construct the corresponding measure for a class of
finite-dimensional systems and compare its predictions for various observables
with the outcome of the out of equilibrium dynamics at large times. We discuss
in detail the connection with the effective temperatures that appear in out of
equilibrium glass theories, as well as the relation between our computation and
those based on `inherent structure' arguments. A short version of this work has
appeared in Phys. Rev. Lett. 85, 5034 (2000) (cond-mat/0006140).

</DOC>
<DOC>
<DOCNO> 101061 </DOCNO>
On the Gribov Problem for Generalized Connections


  The bundle structure of the space $\Ab$ of Ashtekar's generalized connections
is investigated in the compact case. It is proven that every stratum is a
locally trivial fibre bundle. The only stratum being a principal fibre bundle
is the generic stratum. Its structure group equals the space $\Gb$ of all
generalized gauge transforms modulo the constant center-valued gauge
transforms. For abelian gauge theories the generic stratum is globally trivial
and equals the total space $\Ab$. However, for a certain class of non-abelian
gauge theories -- e.g., all SU(N) theories -- the generic stratum is
nontrivial. This means, there are no global gauge fixings -- the so-called
Gribov problem. Nevertheless, there is a covering of the generic stratum by
trivializations each having total induced Haar measure 1.

</DOC>
<DOC>
<DOCNO> 69533 </DOCNO>
Nucleon Properties in the Covariant Quark-Diquark Model


  In the covariant quark-diquark model the effective Bethe-Salpeter (BS)
equations for the nucleon and the $\Delta$ are solved including scalar {\em and
axialvector} diquark correlations. Their quark substructure is effectively
taken into account in both, the interaction kernel of the BS equations and the
currents employed to calculate nucleon observables. Electromagnetic current
conservation is maintained. The electric form factors of proton and neutron
match the data. Their magnetic moments improve considerably by including
axialvector diquarks and photon induced scalar-axialvector transitions. The
isoscalar magnetic moment can be reproduced, the isovector contribution is
about 15% too small. The ratio $\mu G_E/G_M$ and the axial and strong couplings
$g_A$, $g_{\pi NN}$, provide an upper bound on the relative importance of
axialvector diquarks confirming that scalar diquarks nevertheless describe the
dominant 2-quark correlations inside nucleons.

</DOC>
<DOC>
<DOCNO> 122926 </DOCNO>
Eccentric Nuclear Disks with Self Gravity: Predictions for the Double


  We present a method for constructing models of weakly self-gravitating,
finite dispersion eccentric stellar disks around central black holes. The disk
is stationary in a frame rotating at a constant precession speed. The stars
populate quasiperiodic orbits whose parents are numerically integrated periodic
orbits in the total potential. We approximate the quasiperiodic orbits by
distributions of Kepler orbits dispersed in eccentricity and orientation, using
an approximate phase space distribution function written in terms of the Kepler
integrals of motion. We show an example of a model with properties similar to
those of the double nucleus of M31. The properties of our models are primarily
determined by the behavior of the periodic orbits. Self-gravity in the disk
causes these orbits to assume a characteristic radial eccentricity profile,
which gives rise to distinctive multi-peaked line-of-sight velocity
distributions (LOSVDs) along lines of sight near the black hole. The
multi-peaked features should be observable in M31 at the resolution of STIS.
These features provide the best means of identifying an eccentric nuclear disk
in M31, and can be used to constrain the disk properties and black hole mass.

</DOC>
<DOC>
<DOCNO> 84763 </DOCNO>
The Bianchi IX attractor


  We consider the asymptotic behaviour of spatially homogeneous spacetimes of
Bianchi type IX close to the singularity (we also consider some of the other
Bianchi types, e. g. Bianchi VIII in the stiff fluid case). The matter content
is assumed to be an orthogonal perfect fluid with linear equation of state and
zero cosmological constant. In terms of the variables of Wainwright and Hsu, we
have the following results. In the stiff fluid case, the solution converges to
a point for all the Bianchi class A types. For the other matter models we
consider, the Bianchi IX solutions generically converge to an attractor
consisting of the closure of the vacuum type II orbits. Furthermore, we observe
that for all the Bianchi class A spacetimes, except those of vacuum Taub type,
a curvature invariant is unbounded in the incomplete directions of inextendible
causal geodesics.

</DOC>
<DOC>
<DOCNO> 68078 </DOCNO>
The Massive Thermal Basketball Diagram


  The "basketball diagram" is a three-loop vacuum diagram for a scalar field
theory that cannot be expressed in terms of one-loop diagrams. We calculate
this diagram for a massive scalar field at nonzero temperature, reducing it to
expressions involving three-dimensional integrals that can be easily evaluated
numerically. We use this result to calculate the free energy for a massive
scalar field with a phi^4 interaction to three-loop order.

</DOC>
<DOC>
<DOCNO> 84142 </DOCNO>
How much energy do closed timelike curves in 2+1 spacetimes need?


  By noticing that, in open 2+1 gravity, polarized surfaces cannot converge in
the presence of timelike total energy momentum (except for a rotation of 2 pi),
we give a simple argument which shows that, quite generally, closed timelike
curves cannot exist in the presence of such energy condition.

</DOC>
<DOC>
<DOCNO> 13938 </DOCNO>
Electronic Structure of Novel Cation-Radical Salts in High Magnetic


  Two organic conducting materials, where unusual aspects of their composition
play important roles, are explored: beta''-(BEDT-TTF)2SF5XSO3 which exhibits
superconductivity, or a metal-insulator transition (for X=CH2CF2 or CHF
respectively), and tau-(P-S, S -DMEDT-TTF)2 (AuBr2) (AuBr2)y which exhibits a
large, hysteretic, negative magnetoresistance. Detailed angular dependent
magnetoresistance studies that allow a tomographic view of the electronic
structure of these materials with increasing magnetic fields are presented.

</DOC>
<DOC>
<DOCNO> 39669 </DOCNO>
Predicitions for high-energy real and virtual photon-photon scattering


  High-energy virtual photon-virtual photon scattering can be viewed as
interaction of small size color dipoles from the beam and target photons, which
makes $\gamma^{*}\gamma^{*}, \gamma^{*}\gamma$ scattering at high energies
(LEP, LEP200 & NLC) an indispensable probe of short distance properties of the
QCD pomeron exchange. Based on the color dipole representation, we investigate
consequences for the $\gamma^{*}\gamma^{*},\gamma^{*}\gamma$ scattering of the
incorporation of asymptotic freedom into the BFKL equation which makes the QCD
pomeron a series of isolated poles in the angular momentum plane. The emerging
color dipole BFKL-Regge factorization allows us to relate in a
model-independent way the contributions of each BFKL pole to
$\gamma^{*}\gamma^{*},\gamma^{*} \gamma$ scattering and DIS off protons.
Numerical predictions based on our early works on color dipole BFKL
phenomenology of DIS on protons are in a good agreement with the experimental
data on the photon structure function $F_{2\gamma}$ and most recent data on the
$\gamma^*\gamma^*$ cross section $\sigma^{\gamma^*\gamma^*}(Y)$ from OPAL and
L3 experiments at LEP200.
  We discuss the role of non-perturbative dynamics and predict pronounced
effect of the Regge-factorization breaking due to large unfactorizable
non-perturbative corrections to the perturbative vacuum exchange. We comment on
the salient features of the BFKL-Regge expansion for
$\gamma^{*}\gamma^{*},\gamma^{*}\gamma$ scattering including the issue of
decoupling of subleading BFKL poles and the soft plus rightmost hard BFKL pole
dominance .

</DOC>
<DOC>
<DOCNO> 13113 </DOCNO>
Deviations from Matthiessen's Rule for ${\rm SrRuO_3}$ and ${\rm


  We have measured the change in the resistivity of thin films of ${\rm
SrRuO_3}$ and ${\rm CaRuO_3}$ upon introducing point defects by electron
irradiation at low temperatures, and we find significant deviations from
Matthiessen's rule. For a fixed irradiation dose, the induced change in
resistivity {\it decreases} with increasing temperature. Moreover, for a fixed
temperature, the increase in resistivity with irradiation is found to be {\it
sublinear}. We suggest that the observed behavior is due to the marked
anisotropic scattering of the electrons together with their relatively short
mean free path (both characteristic of many metallic oxides including cuprates)
which amplify effects related to the Pippard ineffectiveness condition.

</DOC>
<DOC>
<DOCNO> 122051 </DOCNO>
Winds and Shocks in Galaxy Clusters: Shock Acceleration on an


  We review the possible roles of large scale shocks as particle accelerators
in clusters of galaxies. Recent observational and theoretical work has
suggested that high energy charged particles may constitute a substantial
pressure component in clusters. If true that would alter the expected dynamical
evolution of clusters and increase the dynamical masses consistent with
hydrostatic equilibrium. Moderately strong shocks are probably common in
clusters, through the actions of several agents. The most obvious of these
agents include winds from galaxies undergoing intense episodes of starbursts,
active galaxies and cosmic inflows, such as accretion and cluster mergers. We
describe our own work derived from simulations of large scale structure
formation, in which we have, for the first time, explicitly included passive
components of high energy particles. We find, indeed that shocks associated
with these large scale flows can lead to nonthermal particle pressures big
enough to influence cluster dynamics. These same simulations allow us also to
compute nonthermal emissions from the clusters. Here we present resulting
predictions of gamma-ray fluxes.

</DOC>
<DOC>
<DOCNO> 8864 </DOCNO>
Persistent currents for Coulomb interacting electrons on 2d disordered


  A Wigner crystal structure of the electronic ground state is induced by
strong Coulomb interactions at low temperature in clean or disordered
two-dimensional (2d) samples. For fermions on a mesoscopic disordered 2d
lattice, being closed to a torus, we study the persistent current in the regime
of strong interaction at zero temperature. We perform a perturbation expansion
starting from the Wigner crystal limit which yields power laws for the
dependence of the persistent current on the interaction strength. The sign of
the persistent current in the strong interaction limit is independent of the
disorder realization and strength. It depends only on the electro-statically
determined configuration of the particles in the Wigner crystal.

</DOC>
<DOC>
<DOCNO> 100655 </DOCNO>
Clones on regular cardinals


  We investigate the structure of the lattice of clones on an infinite set X.
We first observe that ultrafilters naturally induce clones; this yields a
simple proof of Rosenberg's theorem:
 "there are 2^2^kappa many maximal (=precomplete) clones on a set of size
kappa." The clones we construct here do not contain all unary functions.
  We then investigate clones that do contain all unary functions. Using a
strong negative partition theorem we show that for many cardinals kappa there
are 2^2^kappa many such clones on a set of size kappa.
  Finally, we show that on a weakly compact cardinal there are exactly 2
maximal clones which contain all unary functions.

</DOC>
<DOC>
<DOCNO> 40191 </DOCNO>
Study of the KL to PI+PI-GAMMA Direct Emission Vertex


  We have perfomed studies of the KL to PI+PI-GAMMA Direct Emission (DE) and
Inner Bremsstrahlung (IB) vertices, based on data collected by KTeV during the
1996 Fermilab fixed target run. We find a1/a2 = -0.737 +- 0.034 GeV^2 for the
DE form-factor parameter in the rho-propagator parametrization, and report on
fits of the form-factor to linear and quadratic functions as well. We
concurrently measure B.R.(KL to PI+PI-GAMMA, E_gamma >20 MeV)/(KL to PI+PI-) =
(20.8 +- 0.3)*10^-3, and a KL to PI+PI-GAMMA DE/(DE + IB) branching ratio of
0.683 +- 0.011.

</DOC>
<DOC>
<DOCNO> 72264 </DOCNO>
Production and decay of the neutral top-pion in high energy $e^{+}e^{-}$


  We study the production and decay of the neutral top-pion $\pi_{t}^{0}$
predicted by topcolor-assisted technicolor(TC2) theory. Our results show that,
except the dominant decay modes $b\bar{b}$, $\bar{t}c$ and $gg$, the
$\pi_{t}^{0}$ can also decay into $\gamma\gamma$ and $Z \gamma$ modes. It can
be significantly produced at high energy $e^{+}e^{-}$ collider(LC) experiments
via the processes $e^{+}e^{-}\to \pi_{t}^{0}\gamma$ and $e^{+}e^{-}\to
Z\pi_{t}^{0}$. We further calculate the production cross sections of the
processes $e^{+}e^{-}\to\gamma\pi_{t}^{0}\to\gamma\bar{t}c$ and $e^{+}e^{-}\to
Z\pi_{t}^{0}\to Z\bar{t}c$. We find that the signatures of the neutral top-pion
$\pi_{t}^{0}$ can be detected via these processes.

</DOC>
<DOC>
<DOCNO> 80661 </DOCNO>
Quark Confinement and Deconfinement Transition in Large Flavor QCD


  We give a new criterion of quark confinement/deconfinement by deriving a
low-energy effective theory of QCD. The effective theory can explain Abelian
dominance in low-energy physics of QCD, especially, quark confinement. Finally,
we apply the above criterion to the large flavor QCD and discuss its phase
structure. The result suggests the existence of conformal phase.

</DOC>
<DOC>
<DOCNO> 85149 </DOCNO>
Vacuum polarization of a scalar field in wormhole spacetimes


  An analitical approximation of $<\phi^2>$ for a scalar field in a static
spherically symmetric wormhole spacetime is obtained. The scalar field is
assumed to be both massive and massless, with an arbitrary coupling $\xi$ to
the scalar curvature, and in a zero temperature vacuum state.

</DOC>
<DOC>
<DOCNO> 122093 </DOCNO>
The FIRST-APM QSO survey (FAQS) in the SBS Region. Preliminary Results


  The main goal of the FIRST-APM QSO Survey (FAQS) survey is to compile the
most complete sample of Bright QSOs, located in the area covered by the Second
Byurakan Survey (SBS). Here we report the first results of an ongoing study
based on the cross-identification of the FIRST radio catalog and the APM
optical catalog. The overlapping sky area between FIRST and SBS is about 700
deg$^{2}$. The compiled list of sources for this overlapping region contains
$\sim 400$ quasar candidates brighter than $B=18\fm5$. About 90 objects were
already spectroscopically classified. During 1999-2000, we observed
spectroscopically more than 150 FAQS objects with the 2.1m telescope of the
Guillermo Haro Observatory (GHO).We have found 51 new QSOs (4 BAL QSOs), 13
Seyfert Galaxies (5 NLSy1's), 23 emission line galaxies, 3 BL Lac objects and
57 stars.

</DOC>
<DOC>
<DOCNO> 85569 </DOCNO>
On Pauli's invention of non-abelian Kaluza-Klein Theory in 1953


  There are documents which show that Wolfgang Pauli developed in 1953 the
first consistent generalization of the five-dimensional theory of Kaluza,
Klein, Fock and others to a higher dimensional internal space. Because he saw
no way to give masses to the gauge bosons, he refrained from publishing his
results formally.

</DOC>
<DOC>
<DOCNO> 7794 </DOCNO>
An Exact Monte Carlo Method for Continuum Fermion Systems


  We offer a new proposal for the Monte Carlo treatment of many-fermion systems
in continuous space. It is based upon Diffusion Monte Carlo with significant
modifications: correlated pairs of random walkers that carry opposite signs;
different functions ``guide'' walkers of different signs; the Gaussians used
for members of a pair are correlated; walkers can cancel so as to conserve
their expected future contributions. We report results for free-fermion systems
and a fermion fluid with 14 $^3$He atoms, where it proves stable and correct.
Its computational complexity grows with particle number, but slowly enough to
make interesting physics within reach of contemporary computers.

</DOC>
<DOC>
<DOCNO> 12427 </DOCNO>
Replica-exchange multicanonical algorithm and multicanonical


  We propose two efficient algorithms for configurational sampling of systems
with rough energy landscape. The first one is a new method for the
determination of the multicanonical weight factor.
 In this method a short replica-exchange simulation is performed and the
multicanonical weight factor is obtained by the multiple-histogram reweighting
techniques. The second one is a further extension of the first in which a
replica-exchange multicanonical simulation is performed with a small number of
replicas. These new algorithms are particularly useful for studying the protein
folding problem.

</DOC>
<DOC>
<DOCNO> 100783 </DOCNO>
Stability of $L^\infty$ solutions for hyperbolic systems with coinciding


  We consider a hyperbolic system of conservation laws u_t + f(u)_x = 0 and
u(0,\cdot) = u_0, where each characteristic field is either linearly degenerate
or genuinely nonlinear. Under the assumption of coinciding shock and
rarefaction curves and the existence of a set of Riemann coordinates $w$, we
prove that there exists a semigroup of solutions $u(t) = \mathcal{S}_t u_0$,
defined on initial data $u_0 \in L^\infty$. The semigroup $\mathcal{S}$ is
continuous w.r.t. time and the initial data $u_0$ in the $L^1_{\text{loc}}$
topology. Moreover $\mathcal{S}$ is unique and its trajectories are obtained as
limits of wave front tracking approximations.

</DOC>
<DOC>
<DOCNO> 121077 </DOCNO>
An algorithm for cleaning extended interferences in radio astronomical


  An algorithm is described for removing extended interferences, for instance
from a radar, which are shorter than the time of passage of a radio source
across the beam of the radio telescope. The algorithm is developed on the basis
of robust procedures with the application of extreme statistics. A procedure of
removing ``jumps'' in observational records is also described. The results of
performance of the algorithms are illustrated in the figures. The cleaning
procedures are included in the standard data reduction system of RATAN-600.

</DOC>
<DOC>
<DOCNO> 100224 </DOCNO>
Convexity of domains of Riemannian manifolds


  In this paper we analyze the problem of the geodesic connectedness of subsets
of Riemannian manifolds. By using variational methods, the geodesic
connectedness of open domains (whose boundaries can be not differentiable and
not convex) of a smooth Riemannian manifold is proved. In some cases also the
convexity of the domain is obtained. Moreover we present examples of the
applicability and of the independence of the assumptions. Finally we give an
application to the existence of trajectories with fixed energy of dynamical
systems.

</DOC>
<DOC>
<DOCNO> 40037 </DOCNO>
Search for New Physics in e mu X Data at D0 Using Sleuth: A


  We present a quasi-model-independent search for the physics responsible for
electroweak symmetry breaking. We define final states to be studied, and
construct a rule that identifies a set of relevant variables for any particular
final state. A new algorithm ("Sleuth") searches for regions of excess in those
variables and quantifies the significance of any detected excess. After
demonstrating the sensitivity of the method, we apply it to the semi-inclusive
channel e mu X collected in 108 pb^-1 of ppbar collisions at sqrt(s) = 1.8 TeV
at the D0 experiment during 1992-1996 at the Fermilab Tevatron. We find no
evidence of new high p_T physics in this sample.

</DOC>
<DOC>
<DOCNO> 100445 </DOCNO>
Homogeneous Coordinates and Quotient Presentations for Toric Varieties


  Generalizing cones over projective toric varieties, we present arbitrary
toric varieties as quotients of quasiaffine toric varieties. Such quotient
presentations correspond to groups of Weil divisors generating the topology.
Groups comprising Cartier divisors define free quotients, whereas $\QQ$-Cartier
divisors define geometric quotients. Each quotient presentation yields
homogeneous coordinates. Using homogeneous coordinates, we express
quasicoherent sheaves in terms of multigraded modules and describe the set of
morphisms into a toric variety.

</DOC>
<DOC>
<DOCNO> 70033 </DOCNO>
Effective Chiral Meson Lagrangian For The Extended Nambu-Jona-Lasinio


  We present a derivation of the low-energy effective meson Lagrangian of the
extended Nambu -- Jona-Lasinio (ENJL) model. The case with linear realization
of broken $SU(2)\times SU(2)$ chiral symmetry is considered. There are two
crucial points why this revision is needed. Firstly it is the explicit chiral
symmetry breaking effect. On the basis of symmetry arguments we show that
relevant contributions related with the current quark mass terms are absent
from the effective Lagrangians derived so far in the literature. Secondly we
suggest a chiral covariant way to avoid non-diagonal terms responsible for the
pseudoscalar -- axial-vector mixing from the effective meson Lagrangian. In the
framework of the linear approach this diagonalization has not been done
correctly. We discuss as well the $SU(2)\times SU(2)/SU(2)$ coset space
parametrization for the revised Lagrangian (nonlinear ansatz). Our Lagrangian
differs in an essential way from those that have been derived till now on the
basis of both linear and nonlinear realizations of chiral symmetry.

</DOC>
<DOC>
<DOCNO> 68619 </DOCNO>
String/M theory


  This is a brief review of the present status, of some recent developments and
of the open challenges in string/M theory.

</DOC>
<DOC>
<DOCNO> 170093 </DOCNO>
A Suggestion for a Teleological Interpretation of Quantum Mechanics


  We suggest solving the measurement problem by postulating the existence of a
special future final boundary condition for the universe. Although this is an
extension of the way boundary conditions are usually chosen (in terrestrial
laboratories), it is our only deviation from standard quantum mechanics. Using
two state vectors, or the "two-state", to describe completely the state of
systems of interest, we analyze ideal and "weak" measurements, and show the
consistency of our scheme. If the final state of a measuring device is assigned
to be one of the possible outcomes of the measurement, an effective reduction
is observed after an ideal measurement process. For final conditions chosen
with an appropriate distribution, the predictions of standard quantum mechanics
may be reconstructed, thus eliminating probability from the description of any
single measurement. The interpretation attained, the Teleological
Interpretation, is an ontological one; it is local and deterministic. Other
special assumptions in the choice of the final boundary condition may explain
certain unaccounted for phenomena, or even supply a mechanism for essential
free will. In this context we believe that a new conception of time should be
adopted.

</DOC>
<DOC>
<DOCNO> 7680 </DOCNO>
Fluctuations of the inverse participation ratio at the Anderson


  Statistics of the inverse participation ratio (IPR) at the critical point of
the localization transition is studied numerically for the power-law random
banded matrix model. It is shown that the IPR distribution function is
scale-invariant, with a power-law asymptotic ``tail''. This scale invariance
implies that the fractal dimensions $D_q$ are non-fluctuating quantities,
contrary to a recent claim in the literature. A recently proposed relation
between $D_2$ and the spectral compressibility $\chi$ is violated in the regime
of strong multifractality, with $\chi\to 1$ in the limit $D_2\to 0$.

</DOC>
<DOC>
<DOCNO> 13540 </DOCNO>
Non-linear growth of periodic patterns


  We study the growth of a periodic pattern in one dimension for a model of
spinodal decomposition, the Cahn-Hilliard equation. We particularly focus on
the intermediate region, where the non-linearity cannot be negected anymore,
and before the coalescence dominates. The dynamics is captured through the
standard technique of a solubility condition performed over a particular family
of quasi-static solutions. The main result is that the dynamics along this
particular class of solutions can be expressed in terms of a simple ordinary
differential equation. The density profile of the stationary regime found at
the end of the non-linear growth is also well characterized. Numerical
simulations correspond satisfactorily to the analytical results through three
different methods and asymptotic dynamics are well recovered, even far from the
region where the approximations hold.

</DOC>
<DOC>
<DOCNO> 120480 </DOCNO>
The broad band spectrum and variability of Seyfert 1


  Recent results on the X-ray spectrum and variability of Seyfert 1 galaxies
are reviewed. New spectral results from BeppoSAX observations are also
presented and briefly discussed.

</DOC>
<DOC>
<DOCNO> 12899 </DOCNO>
Non-Universal Behavior of the k-Body Embedded Gaussian Unitary Ensemble


  Using a novel approach, we investigate the shape of the average spectrum and
the spectral fluctuations of the $k$-body embedded unitary ensemble in the
limit of large matrix dimension. We identify the transition point between
semicircle and Gaussian shape. The transition also affects the spectral
fluctuations which deviate from Wigner-Dyson form and become Poissonian in the
limit $k << m << l$. Here $m$ is the number of Fermions and $l$ the number of
degenerate single-particle states.

</DOC>
<DOC>
<DOCNO> 71340 </DOCNO>
New Physics and the Landau Pole


  In scalar field theories the Landau pole is an ultraviolet singularity in the
running coupling constant that indicates a mass scale at which the theory
breaks down and new physics must intervene. However, new physics at the pole
will in general affect the running of the low energy coupling constant, which
will in turn affect the location of the pole and the related upper limit
(``triviality'' bound) on the low energy coupling constant. If the new physics
is strongly coupled to the scalar fields these effects can be significant even
though they are power suppressed. We explore the possible range of such effects
by deriving the one loop renormalization group equations for an effective
scalar field theory with a dimension 6 operator representing the low energy
effects of the new physics. As an independent check we also consider a
renormalizable model of the high-scale physics constructed so that its low
energy limit coincides with the effective theory.

</DOC>
<DOC>
<DOCNO> 7954 </DOCNO>
Clogging Time of a Filter


  We study the time until a filter becomes clogged due to the trapping of
suspended particles as they pass through a porous medium. This trapping
progressively impedes and eventually stops the flow of the carrier fluid. We
develop a simple description for the pore geometry and the motion of the
suspended particles which, together with extreme-value statistics, predicts
that the distribution of times until a filter clogs has a power-law long-time
tail, with an infinite mean clogging time. These results and its consequences
are in accord with simulations on a square lattice porous network.

</DOC>
<DOC>
<DOCNO> 152224 </DOCNO>
Integrable Quantum Field Theories with Unstable Particles


  The structure of a new family of factorised $S$-matrix theories with
resonance poles is reviewed. They are conjectured to correspond to the
Homogeneous sine-Gordon theories associated with simply laced compact Lie
groups. Two of their more remarkable properties are, first, that some of the
resonance poles can be traced to the presence of unstable particles in the
spectrum, and, second, that they involve several independent mass scales. The
conjectured relationship with the simply laced HSG theories has been checked by
means of the Thermodynamic Bethe ansatz (TBA) and, more recently, through the
explicit calculation of the Form Factors. The main results of the TBA analysis
are summarized.

</DOC>
<DOC>
<DOCNO> 68167 </DOCNO>
Looking for Z' bosons in Supersymmetric E_6 Models through Electroweak


  We review constraints on additional Z' bosons predicted in supersymmetric
(SUSY) E_6 models from electroweak experiments - Z-pole experiments, mW
measurements and the low-energy neutral current (LENC) experiments. Four
representative models - \chi,\psi, \eta, \nu models - are studied in some
detail. We find that the improved data of parity violation in cesium atom,
which is 2.2-\sigma away from the Standard Model (SM) prediction, could be
explained by the exchange of the heavy mass eigenstate Z_2 in the intermediate
state. The improvement over the SM can be found in \chi, \eta, \nu models,
where the total \chi^2 of the fit to the 26 data points decreases by about five
units, owing to the better fit to the atomic parity violation. Impacts of the
kinetic mixing between the U(1)_Y and U(1)' gauge bosons on the \chi^2-analysis
are studied. We find that the Z' model with (\beta_E, \delta)=(-\pi/4,0.2),
where \beta_E is the mixing angle between Z_\chi and Z_\psi bosons and \delta
denotes the kinetic mixing, shows the most excellent fit to the data: the total
\chi^2 decreases by about seven units as compared to the SM. We introduce the
effective mixing parameter \zeta, a combination of the mass and the kinetic
mixing parameters. The 95% CL lower mass bound of Z_2 can be shown as a
function of \zeta. A theoretical prediction on \zeta and the U(1)'gauge
coupling g_E is studied for the \chi,\psi,\eta and \nu models by assuming the
minimal particle content of the SUSY E_6 models.

</DOC>
<DOC>
<DOCNO> 169710 </DOCNO>
Robust unravelings for resonance fluorescence


  Monitoring the fluorescent radiation of an atom unravels the master equation
evolution by collapsing the atomic state into a pure state which evolves
stochastically. A robust unraveling is one that gives pure states that, on
average, are relatively unaffected by the master equation evolution (which
applies once the monitoring ceases). The ensemble of pure states arising from
the maximally robust unraveling has been suggested to be the most natural way
of representing the system [H.M. Wiseman and J.A. Vaccaro, Phys. Lett. A {\bf
250}, 241 (1998)]. We find that the maximally robust unraveling of a resonantly
driven atom requires an adaptive interferometric measurement proposed by
Wiseman and Toombes [Phys. Rev. A {\bf 60}, 2474 (1999)]. The resultant
ensemble consists of just two pure states which, in the high driving limit, are
close to the eigenstates of the driving Hamiltonian $\Omega\sigma_{x}/2$. This
ensemble is the closest thing to a classical limit for a strongly driven atom.
We also find that it is possible to reasonably approximate this ensemble using
just homodyne detection, an example of a continuous Markovian unraveling. This
has implications for other systems, for which it may be necessary in practice
to consider only continuous Markovian unravelings.

</DOC>
<DOC>
<DOCNO> 11408 </DOCNO>
Structure and thermodynamics of colloid-polymer mixtures: a


  The change of the structure of concentrated colloidal suspensions upon
addition of non-adsorbing polymer is studied within a two-component,
Ornstein-Zernicke based liquid state approach. The polymers' conformational
degrees of freedom are considered and excluded volume is enforced at the
segment level. The polymer correlation hole, depletion layer, and excess
chemical potentials are described in agreement with polymer physics theory in
contrast to models treating the macromolecules as effective spheres. Known
depletion attraction effects are recovered for low particle density, while at
higher densities novel many-body effects emerge which become dominant for large
polymers.

</DOC>
<DOC>
<DOCNO> 40246 </DOCNO>
Prospects for Indirect Detection of Neutralino Dark Matter


  Dark matter candidates arising in models of particle physics incorporating
weak scale supersymmetry may produce detectable signals through their
annihilation into neutrinos, photons, or positrons. A large number of relevant
experiments are planned or underway. The `logically possible' parameter space
is unwieldy. By working in the framework of minimal supergravity, we can survey
the implications of the experiments for each other, as well as for direct
searches, collider searches, low-energy experiments, and naturalness in a
transparent fashion. We find that a wide variety of experiments provide
interesting probes. Particularly promising signals arise in the mixed
gaugino-Higgsino region. This region is favored by low-energy particle physics
constraints and arises naturally from minimal supergravity due to the focus
point mechanism. Indirect dark matter searches and traditional particle
searches are highly complementary. In cosmologically preferred models, if there
are charged superpartners with masses below 250 GeV, then some signature of
supersymmetry must appear before the LHC begins operation.

</DOC>
<DOC>
<DOCNO> 12405 </DOCNO>
Communication through a Diffusive Medium: Coherence and Capacity


  Coherent wave propagation in disordered media gives rise to many fascinating
phenomena as diverse as universal conductance fluctuations in mesoscopic metals
and speckle patterns in light scattering. Here, the theory of electromagnetic
wave propagation in diffusive media is combined with information theory to show
how interference affects the information transmission rate between antenna
arrays. Nontrivial dependencies of the information capacity on the nature of
the antenna arrays are found, such as the dimensionality of the arrays and
their direction with respect to the local scattering medium. This approach
provides a physical picture for understanding the importance of scattering in
the transfer of information through wireless communications.

</DOC>
<DOC>
<DOCNO> 101778 </DOCNO>
Apollonian Circle Packings: Number Theory


  Apollonian circle packings arise by repeatedly filling the interstices
between mutually tangent circles with further tangent circles. It is possible
for every circle in such a packing to have integer radius of curvature, and we
call such a packing an {\em integral Apollonian circle packing.} This paper
studies number-theoretic properties of the set of integer curvatures appearing
in such packings. Each Descartes quadruple of four tangent circles in the
packing gives an integer solution to the {\em Descartes equation}, which
relates the radii of curvature of four mutually tangent circles: $2 (x^2 + y^2
+ z^2 + w^2) - (x + y + z + w)^2 = 0.$ Each integral Apollonian circle packing
is classified by a certain {\em root quadruple} of integers that satisfies the
Descartes equation, and that corresponds to a particular quadruple of circles
appearing in the packing. We determine asymptotics for the number of root
quadruples of size below $T$. We study which integers occur in a given integer
packing, and determine congruence restrictions which sometimes apply. Finally,
we present evidence suggesting that the set of integer radii of curvatures that
appear in an integral Apollonian circle packing has positive density, and in
fact represents all sufficiently large integers not excluded by congruence
conditions. In a series of companion papersr ``Apollonian Circle Packings:
Geometry and Group Theory,'' we investigate a variety of group-theoretic
properties of these configurations, as well as various extensions to higher
dimensions and other spaces, such as hyperbolic space.

</DOC>
<DOC>
<DOCNO> 100372 </DOCNO>
Electron Wavefunctions and Densities for Atoms


  With a special `Ansatz' we analyse the regularity properties of atomic
electron wavefunctions and electron densities. In particular we prove an a
priori estimate, $\sup_{y\in B(x,R)}|\nabla\psi(y)| \leq C(R) \sup_{y\in
B(x,2R)}|\psi(y)|$ and obtain for the spherically averaged electron density,
$\widetilde\rho(r)$, that $\widetilde\rho''(0)$ exists and is non-negative.

</DOC>
<DOC>
<DOCNO> 68514 </DOCNO>
Measuring $F_L(x,Q^2)/F_2(x,Q^2)$ from Azimuthal Asymmetries in Deep


  We demonstrate that the angular distribution of hadrons produced in
semi-inclusive deep inelastic final states is related to the inclusive
longitudinal structure function. This relation could provide a new method of
accessing $F_L(x,Q^2)$ in deep inelastic scattering measurements.

</DOC>
<DOC>
<DOCNO> 101543 </DOCNO>
Finite Affine Groups: Cycle Indices, Hall-Littlewood Polynomials, and


  The asymptotic study of the conjugacy classes of a random element of the
finite affine group leads one to define a probability measure on the set of all
partitions of all positive integers. Four different probabilistic
understandings of this measure are given--three using symmetric function theory
and one using Markov chains. This leads to non-trivial enumerative results.
Cycle index generating functions are derived and are used to compute the large
dimension limiting probabilities that an element of the affine group is
separable, cyclic, or semisimple and to study the convergence to these limits.
This yields the first examples of such computations for a maximal parabolic
subgroup of a finite classical group.

</DOC>
<DOC>
<DOCNO> 71598 </DOCNO>
Yang-Mills vacuum instability due to infrared finite lattice gluon


  Using the effective potential approach for composite operators, we have
analytically evaluated the truly nonperturbative vacuum energy density as
obtained by using a model infrared finite gluon propagator which was suggested
by lattice simulations. The truly nonperturbative vacuum energy density is
defined as the truly nonperturbative part of the full gluon propagator
integrated over the deep infrared region (soft momentum region). With this
definition, it is a manifestly gauge invariant quantity. We have explicitly
shown that the corresponding effective potential has always an imaginary part
which means that the vacuum of this model is unstable. Thus this model cannot
have a true ground state.

</DOC>
<DOC>
<DOCNO> 70230 </DOCNO>
Exotic Mesons, Theory and Experiment


  In this talk I summarize the status of exotic mesons, including both
theoretical expectations and experimental candidates. The current experimental
candidates are ``spin-parity exotics''; since these are most often considered
possible hybrid mesons, the theoretical discussion will be mainly concerned
with hybrids. The exotic meson candidates discussed are the surprisingly light
pi_1(1400) and pi_1(1600).

</DOC>
<DOC>
<DOCNO> 10920 </DOCNO>
Hysteretic transition from laminar to vortex shedding flow in soap films


  There are different ways for fluid flow to become turbulent, but usually many
instabilities take place before that. Among these instabilities the transition
from laminar flow to vortex shedding carries significant practical importance.
Here we study a flow, where at high enough flow rates, vortices are generated
by a fixed obstacle (cylinder), which penetrates a flowing, quasi-two
dimensional soap film.
  We present experimental results that demonstrate that the transition from
laminar flow to a periodic K\'arm\'an vortex street can be hysteretic, i.e.
changing the mean flow rate $\bar V$ vortices can survive at velocities lower
than the velocity needed to generate them. This is an unexpected result since
3D experiments are well described by the Hopf equation, which is incompatible
with hysteresis. Beyond that, our data cannot be satisfactorily fitted by the
generic model of hysteresis, i.e. the 5th order Landau equation. It is found
that a phenomenological model describes our experimental findings very well.
  Evidences are presented that wetting properties of the rod, mechanical
instabilities (i.e. vibrations) of the setup, and the effect of the surrounding
air are not the cause of the hysteresis. To reduce three dimensional effects,
the rod was replaced by a disk having a thickness roughly eight times that of
the film. The replacement of the rod by a disk increases the gap width and the
shedding frequency. Behaviour of the system (for instance the unstable
trajectory) in the hysteretic gap is investigated by means of transient
measurements.

</DOC>
<DOC>
<DOCNO> 11853 </DOCNO>
Modeling the viscoelastoplastic response of amorphous glassy polymers


  Constitutive equations are derived for the viscoelastoplastic response of
amorphous glassy polymers at isothermal loading with small strains. A polymer
is treated as an ensemble of cooperatively relaxing regions (CRR) which
rearrange at random times as they are thermally agitated. Rearrangement of CRRs
reflects the viscoelastic response of the bulk medium. At low stresses, CRRs
are connected with each other, which implies that the macro-strain in a
specimen coincides with micro-strains in individual relaxing regions. When the
average stress exceeds some threshold level, links between CRRs break and
relaxing domains begin to slide one with respect to another. Sliding of
micro-domains is associated with the viscoplastic behavior of polymers. Kinetic
equations are proposed for viscoplastic strains and for the evolution of the
threshold stress. These equations are validated by comparison with experimental
data in tensile relaxation tests and in tests with constant strain rates. Fair
agreement is demonstrated between results of numerical simulation and
observations for a polyurethane resin and poly(methyl methacrylate).

</DOC>
<DOC>
<DOCNO> 116392 </DOCNO>
Will the Population of Humanity in the Future be Stabilized?


  A phenomenological theory of growth of the population of humankind is
proposed. The theory based on the assumption about a multifractal nature of the
set of number of people in temporal axis and contains control parameters. In
particular cases the theory coincide with known Kapitza, Foerster, Hoerner
phenomenological theories.

</DOC>
<DOC>
<DOCNO> 70236 </DOCNO>
Scenario for Ultrarelativistic Nuclear Collisions: IV. Effective quark


  Using the framework of wedge dynamics, we compute the effective transverse
mass of a soft quark mode propagating in the expanding background of hard
quarks and gluons created at the earliest time of the collision. We discover
that the wedge dynamics does not require any external infrared or collinear
cut-off. The effective mass is produced mainly due to the forward quark-quark
scattering mediated by the longitudinal (in sense of Gauss' law) magnetic
fields. Contribution of the radiation field is parametrically suppressed.

</DOC>
<DOC>
<DOCNO> 101074 </DOCNO>
On the structure of some typical singularities for implicit ordinary


  We study the systems of ordinary differential equations which are implicit
with respect to the higher derivatives, appearing in the linear form, and their
solutions near the singular points. The invertibility of the higher derivatives
reduces to the singular surface where the theorem of uniqueness and existence
is violated.A set of the singular solution is obtained for the case requiring
the minimal number of additional conditions. The various types of singularities
correspond to these cases. These ``turning'', ``intersection'' singularities
appear in several physical applications.

</DOC>
<DOC>
<DOCNO> 121424 </DOCNO>
Relativistic Effects on Neutrino Pair Annihilation above a Kerr Black


  Using idealized models of the accretion disk we investigate the relativistic
effects on the energy deposition rate via neutrino pair annihilation near the
rotation axis of a Kerr black hole. Neutrinos are emitted from the accretion
disk. The bending of neutrino trajectories and the redshift due to the disk
rotation and gravitation are taken into consideration. The Kerr parameter, $a$,
affects not only neutrinos' behavior but also the inner radius of the accretion
disk. When the deposition energy is mainly contributed by the neutrinos coming
from the central part, the redshift effect becomes dominant as $a$ becomes
large and the energy deposition rate is reduced compared with that neglecting
the relativistic effects. On the other hand, for small $a$ the bending effect
gets dominant and makes energy increase by factor 2 compared with that
neglecting the relativistic effects. For the disk with temperature gradient,
the energy deposition rate for a small inner radius of the accretion disk is
smaller than that estimated by neglecting the relativistic effects. The
relativistic effects, especially for large $a$, play a negative role in
avoiding the baryon contamination problem in gamma-ray bursts.

</DOC>
<DOC>
<DOCNO> 85308 </DOCNO>
Brane-World charges


  As opposed to usual Einstein gravity in four dimensions, the Brane-World
scenario allows the construction of a local density of gravitational energy
(and also of momentum, of angular momentum, etc...). This is a direct
consequence of the hypothesis that our universe is located at the boundary of a
five-dimensional diffeomorphism invariant manifold. We compute these
Brane-World densities of charge using the Lanczos-Israel boundary conditions.
To proceed, we implement an explicitely covariant generalization of the
Hamiltonian procedure of Regge and Teitelboim given in a previous work. We
finally study two simple Brane-World examples.

</DOC>
<DOC>
<DOCNO> 84638 </DOCNO>
Advance of Mercury Perihelion Explained by Cogravity


  The theory of General Relativity explaines the advance of Mercury perihelion
using space curvature and the Schwartzschild metric. We demonstrate that this
phenomena can also be interpreted due to the cogravitational field produced by
the apparent motion of the Sun around Mercury giving exactly the same estimate
as derived from the Schwartzschild metric in general relativity theory. This is
a surprising result because the estimate from both theoretical approaches match
exactly the measured value. The discussion and implications of this result is
out of the scope of the present work.

</DOC>
<DOC>
<DOCNO> 9044 </DOCNO>
Nonlinear Couette flow in a low density granular gas


  A model kinetic equation is solved exactly for a special stationary state
describing nonlinear Couette flow in a low density system of inelastic spheres.
The hydrodynamic fields, heat and momentum fluxes, and the phase space
distribution function are determined explicitly. The results apply for
conditions such that viscous heating dominates collisional cooling, including
large gradients far from the reference homogeneous cooling state. Explicit
expressions for the generalized transport coefficients (e.g., viscosity and
thermal conductivity) are obtained as nonlinear functions of the coefficient of
normal restitution and the shear rate.These exact results for the model kinetic
equation are also shown to be good approximations to the corresponding state
for the Boltzmann equation via comparison with direct Monte Carlo simulation
for the latter

</DOC>
<DOC>
<DOCNO> 83398 </DOCNO>
From Syntactic Theories to Interpreters: A Specification Language and


  Recent years have seen an increasing need of high-level specification
languages and tools generating code from specifications. In this paper, we
introduce a specification language, {\splname}, which is tailored to the
writing of syntactic theories of language semantics. More specifically, the
language supports specifying primitive notions such as dynamic constraints,
contexts, axioms, and inference rules. We also introduce a system which
generates interpreters from {\splname} specifications. A prototype system is
implemented and has been tested on a number of examples, including a syntactic
theory for Verilog.

</DOC>
<DOC>
<DOCNO> 8360 </DOCNO>
Hole-burning experiments within solvable glassy models


  We reproduce the results of non-resonant spectral hole-burning experiments
with fully-connected (equivalently infinite-dimensional) glassy models that are
generalizations of the mode-coupling approach to nonequilibrium situations. We
show that an ac-field modifies the integrated linear response and the
correlation function in a way that depends on the amplitude and frequency of
the pumping field. We study the effect of the waiting and recovery-times and
the number of oscillations applied. This calculation will help descriminating
which results can and which cannot be attributed to dynamic heterogeneities in
real systems.

</DOC>
<DOC>
<DOCNO> 85197 </DOCNO>
The Bardeen Model as a Nonlinear Magnetic Monopole


  The Bardeen model -- the first regular black hole model in General Relativity
-- is reinterpreted as the gravitational field of a nonlinear magnetic
monopole, i.e., as a magnetic solution to Einstein equations coupled to a
nonlinear electrodynamics.

</DOC>
<DOC>
<DOCNO> 84338 </DOCNO>
Some remarks on the Bel-Robinson Tensor


  In this paper we present our point of view on correct physical interpretation
of the Bel-Robinson tensor within the framework of the standard General
Relativity ({\bf GR}), i.e., within the framework of the {\bf GR} without
supplementary elements like arbitrary vector field, distinguished tetrads field
or second metric. We show that this tensor arises as a consequence of the
Bianchi identities and, in a natural manner, it is linked to the differences of
the canonical gravitational energy-momentum calculated in normal coordinates
{\bf NC(P)}.

</DOC>
<DOC>
<DOCNO> 9912 </DOCNO>
Gravity-driven Dense Granular Flows


  We report and analyze the results of numerical studies of dense granular
flows in two and three dimensions, using both linear damped springs and
Hertzian force laws between particles. Chute flow generically produces a
constant density profile that satisfies scaling relations suggestive of a
Bagnold grain inertia regime. The type of force law has little impact on the
behavior of the system. Bulk and surface flows differ in their failure criteria
and flow rheology, as evidenced by the change in principal stress directions
near the surface. Surface-only flows are not observed in this geometry.

</DOC>
<DOC>
<DOCNO> 85590 </DOCNO>
The Isotropy of Compact Universes


  We discuss the problem of the stability of the isotropy of the universe in
the space of ever-expanding spatially homogeneous universes with a compact
spatial topology. The anisotropic modes which prevent isotropy being
asymptotically stable in Bianchi-type $VII_h$ universes with non-compact
topologies are excluded by topological compactness. Bianchi type $V$ and type
$VII_h$ universes with compact topologies must be exactly isotropic. In the
flat case we calculate the dynamical degrees of freedom of Bianchi-type $I$ and
$VII_0$ universes with compact 3-spaces and show that type $VII_0$ solutions
are more general than type $I$ solutions for systems with perfect fluid,
although the type $I$ models are more general than type $VII_0$ in the vacuum
case. For particular topologies the 4-velocity of any perfect fluid is required
to be non-tilted. Various consequences for the problems of the isotropy,
homogeneity, and flatness of the universe are discussed.

</DOC>
<DOC>
<DOCNO> 69673 </DOCNO>
Initial Scales, Supersymmetric Dark Matter and Variations of


  The neutralino-nucleon cross section in the context of the MSSM with
universal soft supersymmetry-breaking terms is compared with the limits from
dark matter detectors. Our analysis is focussed on the stability of the
corresponding cross sections with respect to variations of the initial scale
for the running of the soft terms, finding that the smaller the scale is, the
larger the cross sections become. For example, by taking $10^{10-12}$ GeV
rather than $M_{GUT}$, which is a more sensible choice, in particular in the
context of some superstring models, we find extensive regions in the parameter
space with cross sections in the range of $10^{-6}$--$10^{-5}$ pb, i.e. where
current dark matter experiments are sensitive. For instance, this can be
obtained for $\tan\beta\gsim 3$.

</DOC>
<DOC>
<DOCNO> 102689 </DOCNO>
The spread and extreme terms of Jones polynomials


  We adapt Thistlethwaite's alternating tangle decomposition of a knot diagram
to identify the potential extreme terms in its bracket polynomial, and give a
simple combinatorial calculation for their coefficients, based on the
intersection graph of certain chord diagrams.

</DOC>
<DOC>
<DOCNO> 39704 </DOCNO>
A study of the f0(1370), f0(1500), f0(2000) and f2(1950) observed in the


  The production and decay properties of the f0(1370), f0(1500), f0(2000) and
f2(1950) have been studied in central pp interactions at 450 GeV/c. The dPT,
phi and |t| distributions of these resonances are presented. For the J = 0
states, the f0(1370) and f0(2000) have similar dPT and phi dependences. These
are different to the dPT and phi dependences of the f0(980), f0(1500) and
f0(1710). For the J = 2 states the f2(1950) has different dependences to the
f2(1270) and f2'(1520). This shows that the dPT and phi dependences are not
just J phenomena.

</DOC>
<DOC>
<DOCNO> 71215 </DOCNO>
Constraints on Natural Inflation from Cosmic Microwave Background


  We study constraints on the natural inflation model from the cosmic microwave
background radiation (CMBR). Inflaton \phi for the natural inflation has a
potential of the form V=\Lambda^4[1-\cos(\phi/\sqrt{2}f_\phi)], which is
parametrized by two parameters f_\phi and \Lambda. Various cosmological
quantities, like the primordial curvature perturbation and the CMBR anisotropy,
are determined as functions of these two parameters. Using recent observations
of the CMBR anisotropy by BOOMERANG and MAXIMA (as well as those from COBE),
constraints on the parameters f_\phi and \Lambda are derived. The model with
f_\phi lower than 8.5\times 10^{18} (5.4\times 10^{18}, 4.5\times 10^{18}) GeV
predicts a power spectrum with index n_{\rm S} smaller than 0.95 (0.9, 0.85)
which suppresses the CMBR anisotropy for smaller angular scale. With such a
small n_{\rm S}, height of the second acoustic peak can become significantly
lower than the case of the scale-invariant Harrison-Zeldovich spectrum.

</DOC>
<DOC>
<DOCNO> 70155 </DOCNO>
Field correlators in QCD. Theory and applications


  This review is aimed to demonstrate the basics and use of formalism of
gauge-invariant nonlocal correlators in nonabelian gauge theories. Many
phenomenologically interesting nonperturbative aspects of gluodynamics and QCD
can be described in terms of correlators of the nonabelian field strength
tensors. It is explained how the properties of correlator ensemble encode the
structure of QCD vacuum and determine different nonperturbative observables. It
is argued that in gluodynamics and QCD the dominant role is played by the
lowest nontrivial two-point correlator (Gaussian dominance). Lattice
measurements of field correlators are discussed. Important for the formalism
theoretical tools, such as nonabelian Stokes theorem, background perturbation
theory, cluster expansion, as well as phenomenological applications to the
heavy quarkonium dynamics and QCD phase transition are reviewed.

</DOC>
<DOC>
<DOCNO> 116611 </DOCNO>
Scaling properties of an inviscid mean-motion fluid model


  An inviscid two-dimensional fluid model with nonlinear dispersion that arises
simultaneously in coarse-grained descriptions of the dynamics of the Euler
equation and in the description of non-Newtonian fluids of second grade is
considered. The scaling of the equilibrium states of this model for conserved
energy and enstrophy retains the corresponding scaling for the Euler equations
on the large scales and at the same time greatly deemphasizes the importance of
small scales. This is the first clear demonstration of the beneficial effect of
nonlinear dispersion in the model, and should highlight its utility as a
subgrid model in more realistic situations.

</DOC>
<DOC>
<DOCNO> 119571 </DOCNO>
High-Resolution Imaging of Molecular Gas and Dust in the Antennae (NGC


  We present new aperture synthesis CO maps of the Antennae (NGC 4038/39)
obtained with the Caltech Millimeter Array. These sensitive images show
molecular emission associated with the two nuclei and a partial ring of star
formation to the west of NGC 4038, as well as revealing the large extent of the
extra-nuclear region of star formation (the ``overlap region''), which
dominates the CO emission from this system. The largest molecular complexes
have masses of 3-6x10^8 M_sun, typically an order of magnitude larger than the
largest structures seen to date in more quiescent galaxy disks. The extremely
red luminous star clusters identified previously with HST are well-correlated
with the CO emission, which supports the conclusion that they are highly
embedded young objects rather than old globular clusters. There is an excellent
correlation between the CO emission and the 15 micron emission seen with ISO,
particularly for the brightest regions. The most massive complexes in the
overlap region have similar [NeIII]/[NeII] ratios, which implies that all these
regions are forming many massive stars. However, only the brightest
mid-infrared peak shows strong, rising continuum emission longward of 10
microns, indicative of very small dust grains heated to high temperatures by
their proximity to nearby luminous stars. Since these grains are expected to be
removed rapidly from the immediate environment of the massive stars, it is
possible that this region contains very young (< 1 Myr) sites of star
formation. Alternatively, fresh dust grains could be driven into the sphere of
influence of the massive stars, perhaps by the bulk motions of two giant
molecular complexes. The kinematics and morphology of the CO emission in this
region provide some support for this second scenario.

</DOC>
<DOC>
<DOCNO> 99990 </DOCNO>
A holistic finite difference approach models linear dynamics


  I prove that a centre manifold approach to creating finite difference models
will consistently model linear dynamics as the grid spacing becomes small.
Using such tools of dynamical systems theory gives new assurances about the
quality of finite difference models under nonlinear and other perturbations on
grids with finite spacing. For example, the advection-diffusion equation is
found to be stably modelled for all advection speeds and all grid spacing. The
theorems establish an extremely good form for the artificial internal boundary
conditions that need to be introduced to apply centre manifold theory. When
numerically solving nonlinear partial differential equations, this approach can
be used to derive systematically finite difference models which automatically
have excellent characteristics. Their good performance for finite grid spacing
implies that fewer grid points may be used and consequently there will be less
difficulties with stiff rapidly decaying modes in continuum problems.

</DOC>
<DOC>
<DOCNO> 100256 </DOCNO>
Broadly-Pluriminimal Submanifolds of Kaehler-Einstein Manifolds


  We define broadly-pluriminimal immersed 2n-submanifold F: M --> N into a
Kaehler-Einstein manifold of complex dimension 2n and scalar curvature R. We
prove that, if M is compact, n \geq 2, and R < 0, then: (i) Either F has
complex or Lagrangian directions; (ii) If n = 2, M is oriented, and F has no
complex directions, then it is a Lagrangian submanifold, generalising the
well-known case n = 1 for minimal surfaces due to Wolfson. We also prove that,
if F has constant Kaehler angles with no complex directions, and is not
Lagrangian, then R = 0 must hold. Our main tool is a formula on the Laplacian
of a symmetric function on the Kaehler angles.

</DOC>
<DOC>
<DOCNO> 121669 </DOCNO>
Neutrino-Driven Jets and Rapid-Process Nucleosynthesis


  We have studied whether the jet in a collapse-driven supernova can be a key
process for the rapid-process (r-process) nucleosynthesis. We have examined the
features of a steady, subsonic, and rigidly rotating jet in which the
centrifugal force is balanced by the magnetic force. As for the models in which
the magnetic field is weak and angular velocity is small, we found that the
r-process does not occur because the final temperature is kept to be too high
and the dynamical timescale becomes too long when the neutrino luminosities are
set to be high. Even if the luminosities of the neutrinos are set to be low,
which results in the low final temperature, we found that the models do not
give a required condition to produce the r-process matter. Furthermore, the
amount of the mass outflow seems to be too little to explain the solar-system
abundance ratio in such low-luminosity models. As for the models in which the
magnetic field is strong and angular velocity is large, we found that the
entropy per baryon becomes too small and the dynamical timescale becomes too
long. This tendency is, of course, a bad one for the production of the
r-process nuclei. As a conclusion, we have to say that it is difficult to cause
a successful r-process nucleosynthesis in the jet models in this study.

</DOC>
<DOC>
<DOCNO> 85571 </DOCNO>
Gauge-invariant and coordinate-independent perturbations of stellar


  In Paper I in this series we constructed evolution equations for the complete
gauge-invariant linear perturbations of a time-dependent spherically symmetric
perfect fluid spacetime. A key application of this formalism is the interior of
a collapsing star. Here we derive boundary conditions at the surface of the
star, matching the interior perturbations to the well-known perturbations of
the vacuum Schwarzschild spacetime outside the star.

</DOC>
<DOC>
<DOCNO> 11352 </DOCNO>
Dynamical Structure Factors of the S=1/2 Bond-Alternating Spin Chain


  The dynamical structure factor of the S=1/2 bond-alternating spin chain with
a next-nearest-neighbor interaction in magnetic field is investigated using the
continued fraction method based on the Lanczos algorithm. When the plateau
exists on the magnetization curve, the longitudinal dynamical structure factor
shows a large intensity with a periodic dispersion relation, while the
transverse one shows a large intensity with an almost dispersionless mode. The
periodicity and the amplitude of the dispersion relation in the longitudinal
dynamical structure factor are sensitive to the coupling constants. The
dynamical structure factor of the S=1/2 two-leg ladder in magnetic field is
also calculated in the strong interchain-coupling regime.
  The dynamical structure factor shows gapless or gapful behavior depending on
the wave vector along the rung.

</DOC>
<DOC>
<DOCNO> 101680 </DOCNO>
A space with only Borel subsets


  Miklos Laczkovich asked if there exists a Haussdorff (or even normal) space
in which every subset is Borel yet it is not meager. The motivation of the last
condition is that under MA_kappa every subspace of the reals of cardinality
kappa has the property that all subsets are F_sigma, however Martin's axiom
also implies that these subsets are meager. Here we answer Laczkovich'
question.

</DOC>
<DOC>
<DOCNO> 118164 </DOCNO>
A submillimetre survey of the star-formation history of radio galaxies


  We present the results of the first major systematic submillimetre survey of
radio galaxies spanning the redshift range 1 < z < 5. The primary aim of this
work is to elucidate the star-formation history of this sub-class of elliptical
galaxies by tracing the cosmological evolution of dust mass. Using SCUBA on the
JCMT we have obtained 850-micron photometry of 47 radio galaxies to a
consistent rms depth of 1 mJy, and have detected dust emission in 14 cases. The
radio galaxy targets have been selected from a series of low-frequency radio
surveys of increasing depth (3CRR, 6CE, etc), in order to allow us to separate
the effects of increasing redshift and increasing radio power on submillimetre
luminosity. Although the dynamic range of our study is inevitably small, we
find clear evidence that the typical submillimetre luminosity (and hence dust
mass) of a powerful radio galaxy is a strongly increasing function of redshift;
the detection rate rises from 15 per cent at z < 2.5 to 75 per cent at z > 2.5,
and the average submillimetre luminosity rises as (1+z)^3 out to z~4. Moreover
our extensive sample allows us to argue that this behaviour is not driven by
underlying correlations with other radio galaxy properties such as radio power,
radio spectral index, or radio source size/age. Although radio selection may
introduce other more subtle biases, the redshift distribution of our detected
objects is in fact consistent with the most recent estimates of the redshift
distribution of comparably bright submillimetre sources discovered in blank
field surveys. The evolution of submillimetre luminosity found here for radio
galaxies may thus be representative of massive ellipticals in general.

</DOC>
<DOC>
<DOCNO> 84661 </DOCNO>
A Consistent Histories approach to the Unruh effect


  Using the HPO approach to consistent histories we re-derive Unruh's result
that an observer constantly accelerating through the Minkowski vacuum appears
to be immersed in a thermal bath. We show that propositions about any symmetry
of the system always form a consistent set and that the probabilities
associated with such propositions are decided by their value in the initial
state. We use this fact to postulate a condition on the decoherence functional
in the HPO set-up. Finally we show that the Unruh effect arises from the fact
that the initial density matrix corresponding to the inertial vacuum can
be written as a thermal density matrix in the Fock basis associated with the
accelerating observer.

</DOC>
<DOC>
<DOCNO> 119579 </DOCNO>
Magnetic fields around black holes


  The electromagnetic field near a rotating black hole is being explored in
educational style here. By employing analytic solutions for electrovacuum
fields, we plot the surfaces of constant flux and we show how the field is
dragged around the black hole by purely geometrical effects of the strong
gravitational field. We visualize the structure of magnetic lines and we also
propose possible astrophysical applications of more realistic situations
involving the presence of plasma: The entangled and twisted field lines result
in reconnection processes which accelerate the particles injected into the
vicinity of the black hole. Such acceleration mechanisms of the electromagnetic
origin are considered as a possible source of high-speed outflows emerging from
numerous nuclei of galaxies where black holes reside.

</DOC>
<DOC>
<DOCNO> 9449 </DOCNO>
Weak ferromagnetism of quasi-one-dimensional S=1/2 antiferromagnet


  Weak ferromagnetism of quasi-one-dimensional S = 1/2 antiferromagnet
BaCu$_2$Ge$_2$O$_7$ is studied by the magnetization measurement. The
spontaneous magnetization appears along the b axis. The local symmetry between
the in-chain nearest neighbor spins allows the presence of
Dzyaloshinskii-Moriya interaction, and the only possible spatial configuration
of the weak ferromagnetic moment per spin determines the sign of the
inter-chain interaction. A weak $a$-axis magnetic field can change the
direction of the magnetization to the $a$-axis direction, which shows that the
spin chain forms a weakly coupled weak-ferromagnetic chain system.

</DOC>
<DOC>
<DOCNO> 120519 </DOCNO>
Molecular Clouds Around a Run-away O Star, zeta Oph


  Molecular clouds around a run-away O star z Oph have been surveyed with
NANTEN telescope and their streaming motion caused by z Oph has been detected.
z Oph is the earliest member of the Sco OB2 association and is a runaway star
rapidly moving with an HII region, S27. We detected 2 major filamentary cloud
complexes; one including L156 (L156 complex) is lying across nearly the center
of S27, and the other one (L204 complex) is located near the eastern edge of
S27. Total masses of them traced by the 12CO are 520 Mo and 1110 Mo,
respectively. Denser cloud cores detected in C18O are locally distributed on
the near side of the L204 complex to z Oph, and lower density gas traced by
12CO spreads toward the opposite side. Both complexes have radial velocity
shifts that are correlated with the gas density. These spatial and velocity
structures can be interpreted as follows; (1) the L156 complex is stuck on the
expanding Stromgrem sphere and has been accelerated, (2) the gas in L204
complex was compressed and has also been accelerated outward by z Oph,
resulting the radial velocity shifts of diffuse low-density gas relative to the
dense cores embedded in the clouds. These density and velocity structures
indicate dynamical interaction between the HII region and the molecular clouds.
The cloud complexes are divided into 7 clouds by intensity distributions. In
order to investigate the acceleration mechanism, we calculated momentum and
kinetic energy for each cloud. They range from 60 to 800 Mo km/s and from 0.9
to 21 times 10^45 erg, respectively. We examined the effects of the stellar
wind and photo evaporation by UV field of z Oph and found that the stellar wind
can hardly input the momentum during the crossing time of the movement of z
Oph. UV radiation seems to be a more likely origin of the streaming gas motion.

</DOC>
<DOC>
<DOCNO> 170248 </DOCNO>
Local-field effect in atom optics of two-component Bose-Einstein


  Starting from the first principles of nonrelativistic QED we have developed
the quantum theory of the interaction of a two-component ultracold atomic
ensemble with the electromagnetic field of vacuum and laser photons. The main
attention has been paid to the consistent consideration of dynamical
dipole-dipole interactions in the radiation field. Taking into account
local-field effects we have derived the system of Maxwell-Bloch equations.
Optical properties of the two-component Bose gas are investigated. It is shown
that the refractive index of the gas is given by the Maxwell-Garnett formula.
All equations which are used up to now for the description of the behavior of
an ultracold atomic ensemble in a radiation field can be obtained from our
general system of equations in the low-density limit. Raman-Nath diffraction of
the two-component atomic beam is investigated on the basis of our general
system of equations.

</DOC>
<DOC>
<DOCNO> 119561 </DOCNO>
Normal Galaxies in the Infrared


  This review addresses what can be learned from infrared observations about
galaxies powered predominantly by star formation. Infrared techniques mostly
probe the interstellar medium of galaxies, yielding physical and chemical
information on the medium out of which stars form, which is in turn affected by
those stars. Methods traditionally used in the study of such normal galaxies at
wavelengths longer than 3 microns are described, and major questions currently
pursued in the field are outlined. The most prominent results from the IRAS
survey are reviewed. Contributions by ISO in the field of broad-band photometry
are then presented, followed by ISO results in spectrospcopy. Normal galaxy
studies not directly concerned with the ISM are quickly reviewed. The outlook
and challenges in pursuing the interpretation of infrared data on the ISM are
discussed.

</DOC>
<DOC>
<DOCNO> 12481 </DOCNO>
The Electrochemical Carbon Nanotube Field-Effect Transistor


  We explore the electric-field effect of carbon nanotubes (NTs) in
electrolytes. Due to the large gate capacitance, Fermi energy shifts of order
+/- 1 V can be induced, enabling to tune NTs from p to n-type. Consequently,
large resistance changes are measured. At zero gate voltage the NTs are hole
doped in air with E_F ? 0.3-0.5 eV, corresponding to a doping level of ?
10^{13} cm^{-2}. Hole-doping increases in the electrolyte. This hole doping
(oxidation) is most likely caused by the adsorption of oxygen in air and
cations in the electrolyte.

</DOC>
<DOC>
<DOCNO> 122636 </DOCNO>
XTE J1118+480: Clues on the Nature of the Accretion Flow from the


  We show how the simultaneous presence of a strong quasi periodic oscillation
(QPO) of period of about 10 seconds in the optical and X-ray lightcurves of the
X-ray transient XTE J1118+480 can be used to obtain information about the
nature of the accretion flow around the source. The unusually high
optical-to-X-ray flux ratio and the QPO observed simultaneously in both energy
bands suggest that a significant fraction of the optical flux might originate
close to the central source, where most of the X-rays are produced and be
indicative of a magnetically dominated corona. We also show how the temporal
evolution of the QPO can provide us with information on both the inner radius
and the viscous properties of the optically thick accretion disc.

</DOC>
<DOC>
<DOCNO> 84503 </DOCNO>
Cosmic Strings Lens Phenomenology: General Properties of Distortion


  We reconsider the general properties of gravitational lensing effects induced
by cosmic string systems, taking into account their equation of state and
motion equations. We explicitly show that the deflection patterns induced by a
string is equivalent to the one of a lineic and static distribution of matter.
We then rigorously show that the convergence part of the deformation field is
always zero, except on the intersection of the string worldsheet and the
observer past light cone, extending previous results obtained in peculiar
cases. Phenomenological consequences of this result on multiple image systems
are investigated.

</DOC>
<DOC>
<DOCNO> 118791 </DOCNO>
X-ray Transients Monitored by the All-Sky Monitor on RXTE: A Tabulation


  We present a tabulation of 46 transient x-ray sources monitored with the
All-Sky Monitor (ASM) on the Rossi X-ray Timing Explorer (RXTE). They fall into
four broad categories: short (~d), intermediate, and long (>500 d) duration of
outbursts, and long period binary systems that flare up at periastron (e.g., Be
systems). The mixture of outburst/quiescent cycles and low-level persistent
emission in a few systems could indicate conditions are near the limit for
stable mass flow in the accretion disk. The two short-time-scale systems, CI
Cam and V4641 Sgr, are within 1 kpc of the sun, and hence many more such
systems may await discovery.

</DOC>
<DOC>
<DOCNO> 69892 </DOCNO>
The Infrared Behavior of QCD Green's Functions - Confinement, Dynamical


  Recent studies of QCD Green's functions and their applications in hadronic
physics are reviewed. We briefly discuss the issues of gauge fixing, BRS
invariance and positivity. Evidence for the violation of positivity by quarks
and transverse gluons in the covariant gauge is collected, and it is argued
that this is one manifestation of confinement.
  We summarise the derivation of the Dyson-Schwinger equations (DSEs) of QED
and QCD. The influence of instantons on DSEs in a 2-dimensional model is
mentioned. Solutions for the Green's functions in QED in 2+1 and 3+1 dimensions
provide tests of various schemes to truncate DSEs. We discuss possible
extensions to QCD and their limitations. Truncation schemes for DSEs of QCD are
discussed in the axial gauge and in the Landau gauge. We review the available
results from a systematic non-perturbative expansion scheme established for
Landau gauge QCD. Comparisons to related lattice results, where available, are
presented.
  The applications of QCD Green's functions to hadron physics are summarized.
Properties of ground state mesons are discussed on the basis of the
Bethe-Salpeter equation for quarks and antiquarks. The Goldstone nature of
pseudoscalar mesons and mechanisms of diquark confinement are reviewed. We
discuss some properties of ground state baryons based on their description as
Bethe-Salpeter/Faddeev bound states of quark-diquark correlations in the
quantum field theory of confined quarks and gluons.

</DOC>
<DOC>
<DOCNO> 122169 </DOCNO>
Are Cluster Radio Relics Revived Fossil Radio Cocoons?


  A new model for the, so called, `cluster radio relics' is presented (Ensslin
& Gopal-Krishna 2000). Fossil radio cocoons, resulting from the former activity
of radio galaxies, should contain a low energy relativistic electron population
and magnetic fields. Electrons with an age of even up to 2 Gyr can be
re-accelerated adiabatically to radio emitting energies, if the fossil radio
plasma gets compressed in an environmental shock wave. Such a wave can be
caused by a merging event of galaxy clusters, or by the accretion onto galaxy
clusters. An implication of this model is the existence of a population of
diffuse, ultra-steep spectrum, very low-frequency radio sources located inside
and possibly outside of clusters of galaxies, tracing the revival of aged
fossil radio plasma by the shock waves associated with large-scale structure
formation.

</DOC>
<DOC>
<DOCNO> 120993 </DOCNO>
Spectroscopy of diffuse ionized gas in halos of selected edge-on


  In order to examine the excitation and ionization mechanism of extraplanar
diffuse ionized gas (DIG) we have obtained optical longslit spectra of seven
edge-on spiral galaxies. In four objects the brightest emission lines can be
traced out to distances of typically 1.5 kpc above the disk. For NGC1963 and
NGC3044 line ratios such as [NII]6583/Ha or [SII]6717/Ha as well as
[OIII]5007/Hb could be measured for the halo DIG. This allows us to discuss the
DIG in the halo of these objects in the framework of diagnostic diagrams. For
these two objects, the line ratios of [OIII]5007/Hb decrease with increasing z,
different from the recently reported trend in NGC891 (Rand 1998). We find that
emission lines from the DIG in the disks are in good agreement with
photoionization models using a dilute radiation field. However, with increasing
z these models fail to predict the measured [OI]6300/Ha and HeI5876/Ha line
ratios for NGC1963. Diagnostic diagrams reveal for NGC1963 the need for a
second ionization mechanism of the halo DIG (besides photoionization). This
additional source could be shock ionization. The same diagrams demonstrate an
intermediate classification for NGC3044. Plots of [SII]/[NII] vs. emission
measure reveal significant changes towards the halo and seem to trace local
small scale density fluctuations of the extraplanar DIG.

</DOC>
<DOC>
<DOCNO> 85624 </DOCNO>
Data analysis of gravitational-wave signals from spinning neutron stars.


  We develop a set of data analysis tools for a realistic all-sky search for
continuous gravitational-wave signals. The methods that we present apply to
data from both the resonant bar detectors that are currently in operation and
the laser interferometric detectors that are in the final stages of
construction and commissioning. We show that with our techniques we shall be
able to perform an all-sky 2-day long coherent search of the narrow-band data
from the resonant bar EXPLORER with no loss of signals with the dimensionless
amplitude greater than $2.8\times10^{-23}$.

</DOC>
<DOC>
<DOCNO> 102698 </DOCNO>
On the PCT--Theorem in the Theory of Local Observables


  We review the PCT-theorem and problems connected with its demonstration. We
add a new proof of the PCT-theorem in the theory of local observables which is
similar to that one of Jost in Wightman quantum field theory. We also look at
consequences in case the PCT-symmetry is given on the algebraic level. At the
end we present some examples which answer general questions and throw some
light on open problems.

</DOC>
<DOC>
<DOCNO> 118131 </DOCNO>
Effects of Massive Star Formation on the ISM of Dwarf Galaxies


  We are studying star formation effects on the properties of the ISM in low
metallicity environments using mid-infrared (MIR) and far-infrared (FIR)
observations of starbursting dwarf galaxies taken with the Infrared Space
Observatory (ISO) and the Kuiper Airborne Observatory (KAO). Effects of the
hard pervasive radiation field on the gas and dust, due to the dust-poor
environments are apparent in both the dust and gas components. From a 158
micron [CII] survey we find enhanced I[CII]/FIR ratios in dwarf galaxies and
I[CII]/I(CO) ratios up to 10 times higher than those for normal metallicity
starburst galaxies. We consider MIR observations in understanding the star
formation properties of dwarf galaxies and constraints on the stellar SED.
Notably, the strong MIR [NeIII]/[NeII] ratios reveal the presence of current
massive stellar populations < 5 My old in NGC1569, NGC1140 and IIZw40. The MIR
unidentified infrared bands (UIBs) are weak, if present at all, as a general
characteristic in low metallicity environments, revealing the destruction of
the smallest carbon particles (e.g. PAHs) over large spatial scales. This is
confirmed with our dust modeling: mass fractions of PAHs are almost negligible
compared to the larger silicate grains emitting in the FIR as well as the small
carbon grains emitting in the MIR, which appear to be the source of the
photoelectric gas heating in these galaxies, in view of the [CII] cooling.

</DOC>
<DOC>
<DOCNO> 11131 </DOCNO>
Distinguishing fractional and white noise in one and two dimensions


  We discuss the link between uncorrelated noise and Hurst exponent for one and
two-dimensional interfaces. We show that long range correlations cannot be
observed using one-dimensional cuts through two-dimensional self-affine
surfaces whose height distributions are characterized by a Hurst exponent lower
than -1/2. In this domain, fractional and white noise are not distinguishable.
A method analysing the correlations in two dimensions is necessary. For Hurst
exponents larger than -1/2, a crossover regime leads to a systematic over
estimate of the Hurst exponent.

</DOC>
<DOC>
<DOCNO> 116722 </DOCNO>
Instantaneous response of the ionosphere to a sudden commencement of the


  We developed a new technology for global detection of atmospheric
disturbances, on the basis of phase measurements of the total electron content
(TEC) using an international GPS networks. Temporal dependencies of TEC are
obtained for a set of spaced receivers of the GPS network simultaneously for
the entire set of visible satellites. These series are subjected to filtering
in the selected range of oscillation periods using known algorithms for
spatio-temporal analysis of signals. An "instantaneous" ionospheric response to
the sudden commencement of a strong magnetic storm of April 6, 2000 was
detected. On the dayside of the Earth the largest value of the net response
amplitude was found to be of order 0.8*10^16 m^-2 (1--2 % of the background TEC
value), and the delay with respect to the SC in mid-latitudes was about 200 s.
In higher latitudes the delay goes as long as 15 min. On the nightside these
values are 0.2*10^16 m^-2 and 30 min, respectively. The velocity of the
traveling disturbance from the middle to high latitudes on the dayside as well
as from the dayside to the nightside was about 10-20 km/s.

</DOC>
<DOC>
<DOCNO> 99954 </DOCNO>
The volume and lengths on a three sphere


  We show that the volume of any Riemannian metric on a three sphere is bounded
below by the length of the shortest closed curve that links its antipodal
image. In particular, the volume is bounded below by the minimum of the length
of the shortest closed geodesic and the minimal distance between antipodal
points.

</DOC>
<DOC>
<DOCNO> 99991 </DOCNO>
Deformations of Galois representations arising from degenerate


  Nigel Boston and Barry Mazur have shown how to determine the natural
subspaces of certain S_3-extensions of the rationals, which they term
"generic". We extend some of their results to another class of extensions,
called "degenerate".

</DOC>
<DOC>
<DOCNO> 170186 </DOCNO>
Space-Time Structure as Hidden Variable


  EPR correlations exist and can be observed independently of any a priori
given frame of reference. We can even construct a frame of reference that is
based on these correlations. This observation-based frame of reference is
equivalent to the customary a priori given frame of reference of the laboratory
when describing real EPR experiments. J.S. Bell has argued that local hidden
parameter theories that reproduce the predictions of Quantum Mechanics cannot
exist, but the counterfactual reasoning leading to Bell's conclusion is
physically meaningless if the frame of reference that is based on
EPR-correlations is accepted as the backdrop for EPR-type experiments. The
refutal of Bell's proof opens up for the construction of a viable hidden
parameter theory. A model of a spin h/2 particle in terms of a non-flat metric
of space-time is shown to be able to reproduce the predictions of quantum
mechanics in the Bohm-Aharonov version of the EPR experiment, without
introducing non-locality.

</DOC>
<DOC>
<DOCNO> 169686 </DOCNO>
Controlling Decoherence in Bose-Einstein Condensation by Light


  It is shown that, through a super-radiant Rayleigh scattering, a strong far
off-resonant pump laser applied to a Bose-Einstein condensates(BEC) can induce
a non-demolition coupling of the many-mode quantized vacuum field to the BEC.
This effective interaction will force the total system of the BEC plus the
light field to evolve from a factorized initial state to an ideal entangled
state and thus result in the quantum decoherence in the BEC. Since the
effective coupling coefficients are mainly determined by the Rabi frequency of
the pump laser, the quantum decoherence process can be controlled by adjusting
the intensity of the pump laser. To study the physical influence of decoherence
on the BEC, we investigate how the coherent tunneling of BEC in a
well-separated tight double wall is suppressed by the effectively-entangled
vacuum modes.

</DOC>
<DOC>
<DOCNO> 152340 </DOCNO>
Classical and quantum aspects of the extended antifield formalism


  Starting from a solution to the classical Batalin-Vilkovisky master
equation,an extended solution to an extended master equation is constructed by
coupling all the observables, the anomaly candidates and the generators of
global symmetries. The construction of the formalism and its applications in
the context of the renormalization of generic and potentially anomalous gauge
theories are reviewed.

</DOC>
<DOC>
<DOCNO> 178857 </DOCNO>
The NN Phase Shifts <3 GeV and Resonance Features


  Solutions SP00, SM00 and FA00 of nucleon-nucleon (NN) phase shift analyzes by
Arndt et al. are used in optical model studies. The partial waves, single
channels J.leq.7 and coupled channels J.leq.6, are scrutinized. The radial
probability distributions and losses of flux are used to identify the known
Delta and N* resonances as well as anticipated other structures. The energy
interval extends to 3 GeV.

</DOC>
<DOC>
<DOCNO> 99867 </DOCNO>
Hydrodynamic profiles for the totally asymmetric exclusion process with


  We study a totally asymmetric simple exclusion process where jumps happen at
rate one, except at the origin where the rate is lower. We prove a hydrodynamic
scaling limit to a macroscopic profile described by a variational formula. The
limit is valid for all values of the slow rate. The only assumption required is
that a law of large numbers holds for the initial particle distribution. This
includes also deterministic initial configurations. The hydrodynamic
description contains as an unknown parameter the macroscopic rate at the
origin, which is strictly larger than the microscopic slow rate. The limit is
proved by the variational coupling method.

</DOC>
<DOC>
<DOCNO> 150870 </DOCNO>
Tachyon Condensation and Brane Descent Relations in p-adic String Theory


  It has been conjectured that an extremum of the tachyon potential of a
bosonic D-brane represents the vacuum without any D-brane, and that various
tachyonic lump solutions represent D-branes of lower dimension. We show that
the tree level effective action of p-adic string theory, the expression for
which is known exactly, provides an explicit realisation of these conjectures.

</DOC>
<DOC>
<DOCNO> 13609 </DOCNO>
Analytical model for a crossover between uncorrelated and fractal


  The thermodynamics of a long self-repulsive chain is studied. In $D<4$
dimensions it shows two distinctly different regimes, corresponding to weak and
strong correlations in the system. A simple microscopic analytical model is
presented which successfully describes both the regimes. The self-consistent
scheme is used, in which the center of mass of a chain is fixed explicitly.
This allows to take correlations into account in an indirect manner.

</DOC>
<DOC>
<DOCNO> 178446 </DOCNO>
A phenomenological analysis of antiproton interactions at low energies


  We present an optical potential analysis of the antiproton-proton
interactions at low energies. Our optical potential is purely phenomenological,
and has been parametrized on data recently obtained by the Obelix Collaboration
at momenta below 180 MeV/c. It reasonably fits annihilation and elastic data
below 600 MeV/c, and allows us for an evaluation of the elastic cross section
and rho-parameter down to zero kinetic energy. Moreover we show that the
mechanism that depresses antiproton-nucleus annihilation cross sections at low
energies is present in antiproton-proton interactions too.

</DOC>
<DOC>
<DOCNO> 178995 </DOCNO>
On Nonlinear Evolution of Axisymmetric Nuclear Surface


  We consider an uniformly charged incompressible nuclear fluid bounded by a
closed surface. It is shown that an evolution of an axisymmetric surface
$\Gamma(\bbox{r},t)\equiv \sigma - \Sigma(z,t) = 0,\quad
\bbox{r}=(\sigma,\phi,z)$ can be approximately reduced to a motion of a curve
in the $(\sigma,z)$-plane. A nonlinear integro-diffrerential equation for the
contour $\Sigma(z,t)$ is derived. It is pointed on a direct correspondence
between $\Sigma(z,t)$ and a local curvature, that gives possibility to use
methods of differential geometry to analyze an evolution of an axisymmetric
nuclear surface.

</DOC>
<DOC>
<DOCNO> 40142 </DOCNO>
Perspectives in High-Energy Physics


  A personal view of current prospectives in particle physics is presented,
inspired by the contributions to this meeting. Particular emphasis is laid in
precision tests of the Standard Model and the search for the Higgs boson, on
probes of CP violation, on speculations about possible physics beyond the
Standard Model, on neutrino masses and oscillations, on the quest for
supersymmetry, on opportunities @ future accelerators, and on the ultimate
phenomenological challenge offered by the quest for a Theory of Everything.

</DOC>
<DOC>
<DOCNO> 151560 </DOCNO>
Fractional Supersymmetry through Generalized Anyonic algebra


  The construction of anyonic operators and algebra is generalized by using
quons operators. Therefore, the particular versionof fractional supersymmetry
is constructed on the two-dimensional lattice by associating two generalized
anyons of different kinds. The fractional supersymmetry Hamiltonian operator is
obtained on the two-dimensional lattice and the quantum algebra $U_{q}(sl_{2})$
is realized.

</DOC>
<DOC>
<DOCNO> 118627 </DOCNO>
A First Look at the Nuclear Region of M31 with Chandra


  We report on the first observation of the nuclear region of M31 with the
Chandra X-ray Observatory. The nuclear source seen with the Einstein and ROSAT
HRIs is resolved into five point sources. One of these sources is within 1'' of
the M31 central super-massive black hole. As compared to the other point
sources in M31, this nuclear source has an unusual x-ray spectrum. Based on the
spatial coincidence we identify this source with the central black hole, and
note that the unusual spectrum is a challenge to current theories. A bright
transient is detected ~26'' to the west of the nucleus, which may be associated
with a stellar mass black hole.

</DOC>
<DOC>
<DOCNO> 122151 </DOCNO>
A Fractal Analysis of the HI Emission from the Large Magellanic Cloud


  A composite map of HI in the LMC using the ATCA interferometer and the Parkes
multibeam telescope was analyzed in several ways in an attempt to characterize
the structure of the neutral gas and to find an origin for it. Fourier
transform power spectra in 1D, 2D, and in the azimuthal direction were found to
be approximate power laws over 2 decades in length. Delta-variance methods also
showed the same power-law structure. Detailed models of these data were made
using line-of-sight integrals over fractals that are analogous to those
generated by simulations of turbulence with and without phase transitions. The
results suggested a way to measure directly for the first time the
line-of-sight thickness of the cool component of the HI disk of a nearly
face-on galaxy. The signature of this thickness was found to be present in all
of the measured power spectra.
  The character of the HI structure in the LMC was also viewed by comparing
positive and negative images of the integrated emission. The geometric
structure of the high-emission regions was found to be filamentary, whereas the
geometric structure of the low-emission (intercloud) regions was found to be
patchy and round. This result suggests that compressive events formed the
high-emission regions, and expansion events, whether from explosions or
turbulence, formed the low-emission regions. The character of the structure was
also investigated as a function of scale using unsharp masks.
  All of these results suggest that most of the ISM in the LMC is fractal,
presumably the result of pervasive turbulence, self-gravity, and self-similar
stirring.

</DOC>
<DOC>
<DOCNO> 8245 </DOCNO>
Paraxial propagation of a quantum charge in a random magnetic field


  The paraxial (parabolic) theory of a near forward scattering of a quantum
charged particle by a static magnetic field is presented. From the paraxial
solution to the Aharonov-Bohm scattering problem the transverse transfered
momentum (the Lorentz force) is found. Multiple magnetic scattering is
considered for two models: (i) Gaussian $\delta$ -correlated random magnetic
field; (ii) a random array of the Aharonov-Bohm magnetic flux line. The
paraxial gauge-invariant two-particle Green function averaged with respect to
the random field is found by an exact evaluation of the Feynman integral. It is
shown that in spite of the anomalous character of the forward scattering, the
transport properties can be described by the Boltzmann equation. The Landau
quantization in the field of the Aharonov-Bohm lines is discussed.

</DOC>
<DOC>
<DOCNO> 8713 </DOCNO>
Modeling of the Magnetic Susceptibilities of the Ambient- and


  The magnetic susceptibilities chi versus temperature T of powders and single
crystals of the ambient-pressure (AP) and high-pressure (HP) phases of
(VO)_{2}P_{2}O_{7} are analyzed using an accurate theoretical prediction of
chi(T, J1, J2) for the spin-1/2 antiferromagnetic alternating-exchange (J1, J2)
Heisenberg chain. The results are consistent with recent models with two
distinct types of alternating-exchange chains in the AP phase and a single type
in the HP phase. The spin gap for each type of chain is derived from the
respective set of two fitted alternating exchange constants and the one-magnon
dispersion relation for each of the two types of chains in the AP phase is
predicted. The influences of interchain coupling on the derived intrachain
exchange constants, spin gaps, and dispersion relations are estimated using a
mean-field approximation for the interchain coupling. The accuracies of the
spin gaps obtained using fits to the low-T chi(T) data by theoretical low-T
approximations are determined. The results of these studies are compared with
previously reported estimates of the exchange couplings and spin gaps in the AP
and HP phases and with the magnon dispersion relations in the AP phase measured
previously using inelastic neutron scattering.

</DOC>
<DOC>
<DOCNO> 100622 </DOCNO>
Expansion of real valued meromorphic functions into Fourier


  In the main part of the paper, on the basis of contour integration of complex
meromorphic functions whose singularities lie onto an integration contour, in
the first step, a concept of improper integrals absolute existence of
meromorphic functions, as more general one with respect to the concept of
improper integrals convergence (existence), is introduced into analysis. In the
second step, in the case when a modulus of complex parameter tends to infinity,
an interval of improper integrals convergence of parametric meromorphic
functions is defined. In accordance with this, it is shown that the class of
real valued meromorphic functions, whose finitely many isolated singularities
lie onto a real axis segment, may be expanded into Fourier trigonometric
series, separately. At all points of the segment, at which the meromorphic
functions are continuous ones, the Fourier trigonometric series is summable and
its sum is equal to the function values at those points. Finally, that all is
illustrated by two representative examples.

</DOC>
<DOC>
<DOCNO> 10772 </DOCNO>
Spreading, shrinking and fingering instability of polymer films in glow


  Spontaneous spreading of a polymer drop on a solid substrate can be forced by
a low pressure gaseous discharge applied between the cathode that supports the
drop and a remote electrode. We prone to think that the driving force for this
plasma driven spreading is the spatial distribution of the electric field at
the cathode. Two distinct effects caused by the gas plasma are observed:
spreading of a thin film and shrinking of the rest liquid into a spherical drop
upon its own film. The last effect, never reported before, can be addressed to
the effect of the electric stresses developed in the ionic double layer formed
at the polymer/plasma interface. The spreading front displays a fingering
instability similar to that observed earlier in various experimental conditions
\cite{troian,melo}. Theoretical analysis shows that the Marangoni stress acts
as the driving force for the finger growth.

</DOC>
<DOC>
<DOCNO> 10281 </DOCNO>
Braggoriton--Excitation in Photonic Crystal Infiltrated with Polarizable


  Light propagation in a photonic crystal infiltrated with polarizable
molecules is considered. We demonstrate that the interplay between the spatial
dispersion caused by Bragg diffraction and polaritonic frequency dispersion
gives rise to novel propagating excitations, or braggoritons, with intragap
frequencies. We derive the braggoriton dispersion relation and show that it is
governed by two parameters, namely, the strength of light-matter interaction
and detuning between the Bragg frequency and that of the infiltrated molecules.
We also study defect-induced states when the photonic band gap is divided into
two subgaps by the braggoritonic branches and find that each defect creates two
intragap localized states inside each subgap.

</DOC>
<DOC>
<DOCNO> 117989 </DOCNO>
Eccentric discs in binaries with intermediate mass ratios: Superhumps in


  We investigate the role of the eccentric disc resonance in systems with mass
ratios q greater than 1/4, and demonstrate the effects that changes in the mass
flux from the secondary star have upon the disc radius and structure. The
addition of material with low specific angular momentum to its outer edge
restricts a disc radially. Should the mass flux from the secondary be reduced,
it is possible for the disc in a system with mass ratio as large as 1/3 to
expand to the 3:1 eccentric inner Lindblad resonance and for superhumps to be
excited.

</DOC>
<DOC>
<DOCNO> 152524 </DOCNO>
Algebraic Aspects of the Background Field Method


  We discuss some algebraic properties of the background field method. We
introduce an extra gauge-fixing term for the background gauge field right at
the beginning in the action in such a way that BRST invariance is preserved.
The background effective action is considered and it is shown to satisfy both
the Slavnov-Taylor identities and the Ward identities. This allows to prove the
background equivalence theorem by means of the standard techniques. We show
that the Legendre transform W_{bg} of the background gauge invariant action
gives the same physical amplitudes as the original one we started with.
Moreover, we point out that W_{bg} cannot in general be derived from a
classical action by the Gell-Mann-Low formula. Finally, we show that the BRST
doublet generated from the background field does not modify the anomaly of the
original underlying gauge theory. The proof is algebraic and makes no use of
arguments based on power-counting.

</DOC>
<DOC>
<DOCNO> 122692 </DOCNO>
Explosive Nucleosynthesis in Hypernovae


  We examine the characteristics of nucleosynthesis in 'hypernovae', i.e.,
supernovae with very large explosion energies ($ \gsim 10^{52} $ ergs). We
carry out detailed nucleosynthesis calculations for these energetic explosions
and compare the yields with those of ordinary core-collapse supernovae. We find
that both complete and incomplete Si-burning takes place over more extended,
lower density regions, so that the alpha-rich freezeout is enhanced and
produces more Ti in comparison with ordinary supernova nucleosynthesis. In
addition, oxygen and carbon burning takes place in more extended, lower density
regions than in ordinary supernovae. Therefore, the fuel elements O, C, Al are
less abundant while a larger amount of Si, S, Ar, and Ca ("Si") are synthesized
by oxygen burning; this leads to larger ratios of "Si"/O in the ejecta.
Enhancement of the mass ratio between complete and incomplete Si-burning
regions in the ejecta may explain the abundance ratios among iron-peak elements
in metal-poor stars. Also the enhanced "Si"/O ratio may explain the abundance
ratios observed in star burst galaxies. We also discuss other implications of
enhanced [Ti/Fe] and [Fe/O] for Galactic chemical evolution and the abundances
of low mass black hole binaries.

</DOC>
<DOC>
<DOCNO> 122553 </DOCNO>
Tessellation Reconstruction Techniques


  The application of Voronoi and Delaunay tessellation based methods for
reconstructing continuous fields from discretely sampled data sets is
discussed. The succesfull operation as ``multidimensional interpolation''
method is corroborated through their ability to reproduce even intricate
statistical aspects of the analytical predictions of perturbation theory of
cosmic velocity field evolution. The newly developed and fully self-adaptive
technique for density field estimation by means of Delaunay tessellations,
basically exploiting their ``minimum triangulation'' quality, is shown to
succesfully reproduce the morphology of the foamlike structure in N-body
simulations of cosmic structure formation. The full hierarchy of structure is
implicitly and directly reproduced at every spatial resolution scale present in
the particle distribution, at the same time automatically and sharply rendering
its characteristic anisotropic filamentary and wall-like features.

</DOC>
<DOC>
<DOCNO> 170762 </DOCNO>
Entangled coherent states: teleportation and decoherence


  When a superposition $(|\alpha>-|-\alpha>)$ of two coherent states with
opposite phase falls upon a 50-50 beamsplitter, the resulting state is
entangled. Remarkably, the amount of entanglement is exactly 1 ebit,
irrespective of $\alpha$, as was recently discovered by O. Hirota and M.
Sasaki. Here we discuss decoherence properties of such states and give a simple
protocol that teleports one qubit encoded in Schr\"odinger cat states

</DOC>
<DOC>
<DOCNO> 68682 </DOCNO>
Neutrino survival probabilities in magnetic fields


  We show that, for Majorana neutrinos propagating in a constant magnetic
field, the flavour survival probabilities for left-handed neutrinos is the same
as for right-handed neutrinos, i.e., $P^M (\nu_{\alpha L}\to\nu_{\alpha L}) =
 P^M (\nu_{\alpha R}\to\nu_{\alpha R})$, where $\alpha = e, \mu, \tau$, whereas
in the Dirac case the corresponding probabilities $P^D (\nu_{\alpha
L}\to\nu_{\alpha L})$ and $P^D (\bar\nu_{\alpha R}\to\bar\nu_{\alpha R})$ are
in general different. This might lead to a novel way to search for the nature
of neutrinos. We also discuss how this relation for Majorana neutrinos gets
modified when the magnetic field is not constant. However, if matter effects
become important the relation does not hold anymore.

</DOC>
<DOC>
<DOCNO> 170081 </DOCNO>
Experimental observation of nonclassical effects on single-photon


  It is often asserted that quantum effects can be observed in coincidence
detection rates or other correlations, but never in the rate of single-photon
detection. We observe nonclassical interference in a singles rate, thanks to
the intrinsic nonlinearity of photon counters. This is due to a dependence of
the effective detection efficiency on the quantum statistics of the light beam.
Such measurements of detector response to photon pairs promise to shed light on
the microscopic aspects of silicon photodetectors, and on general issues of
quantum measurement and decoherence.

</DOC>
<DOC>
<DOCNO> 71722 </DOCNO>
Extra dimensions prefer large $\tan\beta$


  Assuming that the recent result obtained from the Monte Carlo simulations on
the nonperturbative existence of the pure SU(2) Yang-Mills theory in five
dimensions can be applied to a more general class of higher-dimensional gauge
theories, we derive the conditions imposed by the nontriviality requirement on
the theories. We find that the supersymmetric grand unified theories with extra
dimensions prefer a large value ($\gsim 2$) of $\tan\beta$ of the minimal
supersymmetric standard model, in accord with today's possible observation of
the Higgs particle at LEP2.

</DOC>
<DOC>
<DOCNO> 39863 </DOCNO>
Three Remarks on the MSSM


  First of all, "right" sneutrino can be the lightest supersymmetric particle.
Then, the flavor democracy favors large value of the tan^($beta$). Finally, the
huge number of free parameters in the three families MSSM may be considered as
an indication of SUSY at preonic level.

</DOC>
<DOC>
<DOCNO> 70036 </DOCNO>
Maximum entropy method and oscillations in the diffraction cone


  The maximum entropy method has been applied to investigate the oscillating
structure in the pbarp- and pp-elastic scattering differential cross-section at
high energy and small momentum transfer. Oscillations satisfying quite
realistic reliability criteria have been found.

</DOC>
<DOC>
<DOCNO> 100090 </DOCNO>
On the L^2-stability and L^2 controllability of steady flows of an ideal


  The author studies the flows of an ideal incompressible fluid in a
2-dimensional domain, and in particular questions of instability and
controllability.

</DOC>
<DOC>
<DOCNO> 117285 </DOCNO>
Coulomb plasmas in outer envelopes of neutron stars


  Outer envelopes of neutron stars consist mostly of fully ionized, strongly
coupled Coulomb plasmas characterized by typical densities about 10^4-10^{11}
g/cc and temperatures about 10^4-10^9 K. Many neutron stars possess magnetic
fields about 10^{11}-10^{14} G. Here we briefly review recent theoretical
advances which allow one to calculate thermodynamic functions and electron
transport coefficients for such plasmas with an accuracy required for
theoretical interpretation of observations.

</DOC>
<DOC>
<DOCNO> 178892 </DOCNO>
Kinetic equation with exact charge conservation


  We formulate the kinetic master equation describing the production of charged
particles which are created or destroyed only in pairs due to the conservation
of their Abelian charge.Our equation applies to arbitrary particle
multiplicities and reproduces the equilibrium results for both canonical (rare
particles) and grand canonical (abundant particles) systems. For canonical
systems, the equilibrium multiplicity is much lower and the relaxation time is
much shorter than the naive extrapolation from the grand canonical ensemble
results. Implications for particle chemical equilibration in heavy-ion
collisions are discussed.

</DOC>
<DOC>
<DOCNO> 10891 </DOCNO>
Granulated superconductors:from the nonlinear sigma model to the


  We modify a nonlinear sigma model (NLSM) for the description of a granulated
disordered system in the presence of both the Coulomb repulsion and the Cooper
pairing. We show that under certain controlled approximations this model is
reduced to the Bose-Hubbard (or ``dirty-boson'') model with renormalized
coupling constants. We obtain a more general effective action (which is still
simpler than the full NLSM action) which can be applied in the region of
parameters where the reduction to the Bose-Hubbard model is not justified. This
action may lead to a different picture of the superconductor-insulator
transition in 2D systems.

</DOC>
<DOC>
<DOCNO> 174500 </DOCNO>
Abnormal Radioactive Decays out of Long-Lived Super- and Hyper-Deformed


  Long-lived high-spin super- and hyper-deformed isomeric states, which exhibit
themselves by abnormal radioactive decays, have been observed using the 16O +
197Au and 28Si + 181Ta reactions. They make it possible to understand the
production, via secondary reactions, of the long-lived superheavy element with
Z = 112 and of the abnormally low energy and very enhanced alpha-particle
groups seen in various actinide sources. They might also explain some puzzling
phenomena seen in nature.

</DOC>
<DOC>
<DOCNO> 121105 </DOCNO>
Embedded Star Clusters: The ISO View


  We summarize the main results of a mid-IR photometric survey with ISO for a
few nearby embedded clusters. The sensitivity and spatial resolution of ISOCAM
provided a wonderful tool for studies of the youngest stellar clusters, which
are still deeply embedded in their parent molecular clouds. Mid-IR photometry
is found to be extremely efficient in finding all the young stellar objects
(YSOs) with IR excesses, i.e. mainly T Tauri stars surrounded by circumstellar
disks and also some Class I sources. The spatial distribution of these sources
is highly clustered and even sub-clustered, with a tendency of stronger
concentration for the younger regions. The improved samples of IR-excess YSOs
appear complete down to 0.03 L_sun for the most nearby clusters. This gives
constraints on the mass functions well into the brown dwarf domain. The first
results show that the mass functions of these clusters are identical to the
field star IMF derived by Kroupa et al. (1993) with a flattening of the mass
function at M_star ~ 0.5 M_sun.

</DOC>
<DOC>
<DOCNO> 169679 </DOCNO>
A separability criterion for density operators


  We give a necessary and sufficient condition for a mixed quantum mechanical
state to be separable. The criterion is formulated as a boundedness condition
in terms of the greatest cross norm on the tensor product of trace class
operators.

</DOC>
<DOC>
<DOCNO> 8512 </DOCNO>
Conductivity of composite systems: perturbation theory and


  The paper was withdrawn by the authors

</DOC>
<DOC>
<DOCNO> 170494 </DOCNO>
Theory of quantum computation


  Short review article on quantum computation accepted for Supplement III,
Encyclopaedia of Mathematics (publication expected Summer 2001). See also
http://www.wkap.nl/series.htm/ENM

</DOC>
<DOC>
<DOCNO> 151370 </DOCNO>
((F, D1), D3) bound state, S-duality and noncommutative open


  We study decoupling limits and S-dualities for noncommutative open string/
Yang-Mills theory in a gravity setup by considering an $SL(2,Z)$ invariant
supergravity solution of the form ((F, D1), D3) bound state of type IIB string
theory. This configuration can be regarded as D3-branes with both electric and
magnetic fields turned on along one of the spatial directions of the brane and
preserves half of the space-time supersymmetries of the string theory. Our
study indicates that there exists a decoupling limit for which the resulting
theory is an open string theory defined in a geometry with noncommutativity in
both space-time and space-space directions. We study S-duality of this
noncommutative open string (NCOS) and find that the same decoupling limit in
the S-dual description gives rise to a space-space noncommutative Yang-Mills
theory (NCYM). We also discuss independently the decoupling limit for NCYM in
this D3 brane background. Here we find that S-duality of NCYM theory does not
always give a NCOS theory. Instead, it can give an ordinary Yang-Mills with a
singular metric and an infinitely large coupling. We also find that the open
string coupling relation between the two S-duality related theories is modified
such that S-duality of a strongly coupled open-string/Yang-Mills theory does
not necessarily give a weakly coupled theory. The relevant gravity dual
descriptions of NCOS/NCYM are also given.

</DOC>
<DOC>
<DOCNO> 116748 </DOCNO>
A new regime of anomalous penetration of relativistically strong laser


  It is shown that penetration of relativistically intense laser light into an
overdense plasma, accessible by self-induced transparency, occurs over a finite
length only. The penetration length depends crucially on the overdense plasma
parameter and increases with increasing incident intensity after exceeding the
threshold for self-induced transparency. Exact analytical solutions describing
the plasma-field distributions are presented.

</DOC>
<DOC>
<DOCNO> 174604 </DOCNO>
CEM2k - Recent Developments in CEM


  Recent developments of the Cascade-Exciton Model (CEM) of nuclear reactions
are briefly described. These changes are motivated by new data on isotope
production measured recently in "reverse kinematics" at GSI for interactions of
208-Pb and 238-U at 1 GeV/nucleon and 197-Au at 800 MeV/nucleon with liquid
1-H. This study leads us to CEM2k, which is a new version of the CEM code that
is still under development. The increased accuracy and predictive power of the
code CEM2k are shown by several examples. Further necessary work is outlined.

</DOC>
<DOC>
<DOCNO> 117040 </DOCNO>
On the Physical Nature of the Magnetic-Field Freezing-in Effect in


  Attention is drawn to a fundamental difference between the physical
mechanisms responsible for the magnetic field freezing-in effect in spatially
isotropic (collisional) and strongly anisotropic (collisionless) plasmas. (The
first case is characteristic of internal regions of the Sun and other stars;
the second, for the solar corona, interplanetary and interstellar medium,
planetary ionospheres and magnetospheres, cometary tails.) It is shown that
particles of a collisionless plasma remain in the same field line during their
motion because of the properties of electrodynamic drift which stem from the
divergence-free character of the magnetic field and the equipotentiality of the
field lines (but not as a result of the appearance of induction currents,
compensating variations of the external magnetic flux through a closed contour,
as in the case of isotropic conductivity of the plasma).

</DOC>
<DOC>
<DOCNO> 11780 </DOCNO>
Phase transition in a spatial Lotka-Volterra model


  Spatial evolution is investigated in a simulated system of nine competing and
mutating bacterium strains, which mimics the biochemical war among bacteria
capable of producing two different bacteriocins (toxins) at most. Random
sequential dynamics on a square lattice is governed by very symmetrical
transition rules for neighborhood invasion of sensitive strains by killers,
killers by resistants, and resistants by by sensitives. The community of the
nine possible toxicity/resistance types undergoes a critical phase transition
as the uniform transmutation rates between the types decreases below a critical
value $P_c$ above which all the nine types of strain coexist with equal
frequencies. Passing the critical mutation rate from above, the system
collapses into one of the three topologically identical states, each consisting
of three strain types. Of the three final states each accrues with equal
probability and all three maintain themselves in a self-organizing polydomain
structure via cyclic invasions. Our Monte Carlo simulations support that this
symmetry breaking transition belongs to the universality class of the
three-state Potts model.

</DOC>
<DOC>
<DOCNO> 119202 </DOCNO>
Measurements of the Diffuse Ultraviolet Background and the Terrestrial


  Far-UV observations in and near the Hubble Deep Fields demonstrate that the
Space Telescope Imaging Spectrograph (STIS) can potentially obtain unique and
precise measurements of the diffuse far-ultraviolet background. Although STIS
is not the ideal instrument for such measurements, high-resolution images allow
Galactic and extragalactic objects to be masked to very faint magnitudes, thus
ensuring a measurement of the truly diffuse UV signal. The programs we have
analyzed were not designed for this scientific purpose, but would be sufficient
to obtain a very sensitive measurement if it were not for a weak but
larger-than-expected signal from airglow in the STIS 1450-1900 A bandpass. Our
analysis shows that STIS far-UV crystal quartz observations taken near the limb
during orbital day can detect a faint airglow signal, most likely from NI\1493,
that is comparable to the dark rate and inseparable from the far-UV background.
Discarding all but the night data from these datasets gives a diffuse
far-ultraviolet background measurement of 501 +/- 103 ph/cm2/sec/ster/A, along
a line of sight with very low Galactic neutral hydrogen column (N_HI = 1.5E20
cm-2) and extinction (E(B-V)=0.01 mag). This result is in good agreement with
earlier measurements of the far-UV background, and should not include any
significant contribution from airglow. We present our findings as a warning to
other groups who may use the STIS far-UV camera to observe faint extended
targets, and to demonstrate how this measurement may be properly obtained with
STIS.

</DOC>
<DOC>
<DOCNO> 84735 </DOCNO>
Inflation with a Planck-scale frequency cutoff


  The implementation of a Planck-scale high frequency and short wavelength
cutoff in quantum theories on expanding backgrounds may have potentially
nontrivial implications, such as the breaking of local Lorentz invariance and
the existence of a yet unknown mechanism for the creation of vacuum modes. In
scenarios where inflation begins close to the cutoff scale, these effects could
have observable consequences as trans-Planckian modes are redshifted to
cosmological scales. In close analogy with similar studies of Hawking
radiation, a simple theory of a minimally coupled scalar field in de Sitter
space is studied, with a high frequency cutoff imposed by a nonlinear
dispersion relation. Under certain conditions the model predicts deviations
from the standard inflationary scenario. We also comment on the difficulties in
generalizing fluid models of Hawking radiation to cosmological space-times.

</DOC>
<DOC>
<DOCNO> 151569 </DOCNO>
Boundaries, crosscaps and simple currents


  Universal formulas for the boundary and crosscap coefficients are presented,
which are valid for all symmetric simple current modifications of the charge
conjugation invariant of any rational conformal field theory.

</DOC>
<DOC>
<DOCNO> 83491 </DOCNO>
Questions for a Materialist Philosophy Implying the Equivalence of


  Issues related to a materialist philosophy are explored as concerns the
implied equivalence of computers running software and human observers. One
issue explored concerns the measurement process in quantum mechanics. Another
issue explored concerns the nature of experience as revealed by the existence
of dreams. Some difficulties stemming from a materialist philosophy as regards
these issues are pointed out. For example, a gedankenexperiment involving what
has been called "negative" observation is discussed that illustrates the
difficulty with a materialist assumption in quantum mechanics. Based on an
exploration of these difficulties, specifications are outlined briefly that
would provide a means to demonstrate the equivalence of of computers running
software and human experience given a materialist assumption.

</DOC>
<DOC>
<DOCNO> 151026 </DOCNO>
Gauge dependence of effective action and renormalization group functions


  The Caswell-Wilczek analysis on the gauge dependence of the effective action
and the renormalization group functions in Yang-Mills theories is generalized
to generic, possibly power counting non renormalizable gauge theories. It is
shown that the physical coupling constants of the classical theory can be
redefined by gauge parameter dependent contributions of higher orders in
$\hbar$ in such a way that the effective action depends trivially on the gauge
parameters, while suitably defined physical beta functions do not depend on
those parameters.

</DOC>
<DOC>
<DOCNO> 178398 </DOCNO>
Final state interactions in $^{4}$He(e,e$^\prime$p)$^{3}$H at large


  At large proton energy, the final state interactions of the knocked out
nucleon in $\eep$ reactions off nuclear targets can be described within the
eikonal approximation, treating the spectator particles as a collection of
fixed scattering centers. We use a generalization of this approach, suitable to
take into account the possible occurrence of color transparency, to carry out
an accurate calculation of the missing momentum distribution of the process
$^{4}He(e,e^\prime p)^{3}H$. The pattern of final state interaction effect is
analyzed for different kinematical setups in the domain corresponding to $2 \le
Q^2 \le 20$ (GeV/c)$^2$.

</DOC>
<DOC>
<DOCNO> 120869 </DOCNO>
Acceleration of Particles by Oblique Shocks and Cosmic Ray Spectra


  We consider the first order Fermi acceleration on the presumption that the
shock fronts around supernova remnants cross outer magnetic fields with various
angles. These oblique shocks concerned with, accelerate particles more
efficiently than parallel shocks and elevate the achievable maximum energies.
The primary cosmic ray spectrum is strongly dependent upon these energies. When
indices and absolute fluxes at $10^{12}$ eV are given for several nuclear
groups from experimental data, the total primary spectrum shows a smooth knee
behavior at $\sim 10^{15}$ eV and fits the flux data well up to several times
of $10^{17}$ eV. It is also shown that the chemical composition changes
significantly from lighter to heavier nuclei as energies of particles exceed
the knee. It is compared with data, too.

</DOC>
<DOC>
<DOCNO> 84361 </DOCNO>
Gravitational Aharonov-Bohm effect and gravitational lensing


  Considering the spacetime around a rotating massif body it is seen that the
time of flight of a light ray is different whether it travels on one side of
the source or on the other. The difference is proportional to the angular
momentum of the body. In the case that a compact rapidly rotating object is the
source of a gravitational lensing effect, the contribution coming from the
above mentioned gravitational Aharonov-Bohm effect should be added to the other
causes of phase difference between light rays coming from different images of
the same object.

</DOC>
<DOC>
<DOCNO> 101279 </DOCNO>
A special case of sl(n)-fusion coefficients


  We give a combinatorial description of sl(n)-fusion coefficients in the case
where one partition has at most two columns and establih other properties for
this case.

</DOC>
<DOC>
<DOCNO> 11150 </DOCNO>
On the theory of light scattering in molecular liquids


  The theory of light scattering for a system of linear molecules with
anisotropic polarizabilities is considered. As a starting point for our theory,
we express the result of a scattering experiment in VV and VH symmetry as
dynamic correlation functions of tensorial densities $\rho_{lm}(q)$ with $l=0$
and $l=2$. $l$, $m$ denote indices of spherical harmonics. To account for all
observed hydrodynamic singularities, a generalization of the theory of
Schilling and Scheidsteger \cite{schilling97} for these correlation functions
is presented, which is capable to describe the light scattering experiments
from the liquid regime to the glassy state. As a microscopic theory it fulfills
all sum rules contrary to previous {\em phenomenological} theories. We
emphasize the importance of the helicity index $m$ for the microscopic theory
by showing, that only the existence of $m=1$ components lead to the well known
Rytov dip in liquids and to the appearance of transversal sound waves in VH
symmetry in the deeply supercooled liquid and the glass. Exact expressions for
the phenomenological frequency dependent rotation translation coupling
coefficients of previous theories are derived.

</DOC>
<DOC>
<DOCNO> 152143 </DOCNO>
Magnetic Flux in Toroidal Type I Compactification


  We discuss the compactification of type I strings on a torus with additional
background gauge flux on the D9-branes. The solutions to the cancellation of
the RR tadpoles display various phenomenologically attractive features:
supersymmetry breaking, chiral fermions and the opportunity to reduce the rank
of the gauge group as desired. We also point out the equivalence of the concept
of various different background fields and noncommutative deformations of the
geometry on the individual D9-branes by constructing the relevant boundary
states to describe such objects.

</DOC>
<DOC>
<DOCNO> 70763 </DOCNO>
Search Strategies for non-Standard Higgses at e+e- Colliders


  The Higgs search strategies in minimal non-supersymmetric extensions of the
SM are discussed.

</DOC>
<DOC>
<DOCNO> 68655 </DOCNO>
Hara Theorem, GIM model, and Asymmetry in Weak Radiative Hyperon Decays


  It is shown that in the framework of GIM model,the parity-violating (PV)
$\Sigma^{+}(uus) \Rightarrow p(uud) + \gamma $ decay amplitude does not vanish
but just transforms into another PV decay amplitude, namely, of the
$\Omega^{+}_{cc}(ccs)\to \Xi^{+}_{cc}(ccd)+\gamma $ decay. The known result is
used that the relevant part of the CP-invariant effective current$\times$
current Hamiltonian changes sign under simultaneous quark changes
$d\leftrightarrow s$ and $u\leftrightarrow c$. So, asymmetry of $\Sigma^{+}
\Rightarrow p + \gamma $ decay should not vanish in contrast to the Hara result
of the old-fashioned $SU(3)_{f}$ model. At the same time, the zero asymmetry
prediction persists for the $ \Xi^{-} \Rightarrow \Sigma^{-} + \gamma $ decay.

</DOC>
<DOC>
<DOCNO> 71276 </DOCNO>
Non-perturbative effects in a rapidly expanding quark-gluon plasma


  Within first-order phase transitions, we investigate the pre-transitional
effects due to the nonperturbative, large-amplitude thermal fluctuations which
can promote phase mixing before the critical temperature is reached from above.
In contrast with the cosmological quark-hadron transition, we find that the
rapid cooling typical of the RHIC and LHC experiments and the fact that the
quark-gluon plasma is chemically unsaturated suppress the role of
non-perturbative effects at current collider energies. Significant supercooling
is possible in a (nearly) homogeneous state of quark gluon plasma.

</DOC>
<DOC>
<DOCNO> 8865 </DOCNO>
Spatial distribution of persistent sites


  We study the distribution of persistent sites (sites unvisited by particles
$A$) in one dimensional $A+A\to\emptyset$ reaction-diffusion model. We define
the {\it empty intervals} as the separations between adjacent persistent sites,
and study their size distribution $n(k,t)$ as a function of interval length $k$
and time $t$. The decay of persistence is the process of irreversible
coalescence of these empty intervals, which we study analytically under the
Independent Interval Approximation (IIA). Physical considerations suggest that
the asymptotic solution is given by the dynamic scaling form
$n(k,t)=s^{-2}f(k/s)$ with the average interval size $s\sim t^{1/2}$. We show
under the IIA that the scaling function $f(x)\sim x^{-\tau}$ as $x\to 0$ and
decays exponentially at large $x$. The exponent $\tau$ is related to the
persistence exponent $\theta$ through the scaling relation $\tau=2(1-\theta)$.
We compare these predictions with the results of numerical simulations. We
determine the two-point correlation function $C(r,t)$ under the IIA. We find
that for $r\ll s$, $C(r,t)\sim r^{-\alpha}$ where $\alpha=2-\tau$, in agreement
with our earlier numerical results.

</DOC>
<DOC>
<DOCNO> 69034 </DOCNO>
On the Influence of Einstein-Podolsky-Rosen (EPR) Effect on the


  Evading formation of the domain walls in cosmological phase transitions is
one of the key problems to be solved for getting agreement with the observed
large-scale homogeneity of the Universe. The previous attempts to get around
this obstacle led to imposing severe observational constraints on the
parameters of the fields involved. Our aim is to show that yet another way to
overcome the above problem is accounting for EPR effect. Namely, if the scalar
(Higgs) field was presented by a single quantum state at the initial instant of
time, then its reduction during a phase transition at some later instant should
be correlated even at distances exceeding the local cosmological horizon. By
considering a simplest 1D model with Z_2 Higgs field, we demonstrate that EPR
effect really can substantially reduce the probability of spontaneous creation
of the domain walls.

</DOC>
<DOC>
<DOCNO> 85154 </DOCNO>
Principle of equivalence and wave-particle duality in quantum gravity


  This talk presents: (a) A quantum-mechanically induced violation of the
principle of equivalence, and (b) Gravitationally-induced modification to the
wave particle duality. In this context I note that the agreement between the
predictions of general relativity and observations of the energy loss due to
gravitational waves emitted by binary pulsars is just as impressive as the
agreement between prediction of quantum electrodynamics and the measured value
of Lamb shift in atoms. However, general relativity has not yet yielded to a
successful quantised theory. There is a widespread belief that the two thories
are incompatible at some deep level. The question is: where? Here, I show that
the conceptual foundations of the theory of general relativity and quantum
mechanics are so rich that they suggest concrete modifications into each other
in the interface region. Specifically, I consider quantum states that have no
classical counterpart and show that such states must carry an inherent
violation of the principle of equivalence. On the other hand, I show that when
gravitational effects are incorporated into the quantum measurement process one
must induce a gravitationally induced modification to the de Broglie's
wave-particle duality. The reported changes into the foundations of the two
theories are far from in-principle modifications. These are endowed with
serious implications for the understanding of the early universe and, in
certain instances, can be explored in terrestrial laboratories.

</DOC>
<DOC>
<DOCNO> 120495 </DOCNO>
Disk Galaxies as Cosmological Benchmarks: Cold Dark Matter versus


  We discuss a comparison of models for the formation of disk galaxies both in
a Universe dominated by cold dark matter (CDM) and one in which the force law
is given by modified Newtonian dynamics (MOND). Our main aim is to address the
claim made by McGaugh & de Blok that CDM suffers from severe fine-tuning
problems, which are circumvented under MOND. As we show, CDM indeed requires
some amount of tuning of the feedback efficiencies to obtain a Tully-Fisher
relation (TFR) as steep as observed. However, that same model is in excellent
agreement with a wide variety of additional observations. Therefore, the modest
amount of feedback needed should not be regarded a fine-tuning problem.
Instead, its requirement should be considered a generic prediction for CDM,
which might be tested with future observations and with detailed modeling of
feedback processes. We also show that galaxy formation in a MOND universe can
not simultaneously reproduce the TFR and the lack of high surface brightness
dwarf galaxies. We thus conclude that CDM is a more viable theory for the
formation of disk galaxies than MOND.

</DOC>
<DOC>
<DOCNO> 100923 </DOCNO>
Historic forcing for Depth


  We show that, consistently, for some regular cardinals theta<lambda, there
exists a Boolean algebra B such that B=lambda^+ and for every subalgebra B' of
B of size lambda^+ we have Depth(B')=theta.

</DOC>
<DOC>
<DOCNO> 178546 </DOCNO>
Hyperon-hyperon interactions and properties of neutron matter


  We present results from Brueckner-Hartree-Fock calculatons for beta stable
neutron star matter with nucleonic and hyperonic degress degrees of freedom,
employing the most recent parametrizations of the baryon-baryon interaction of
the Nijmegen group. It is found that the only strange baryons emergin in beta
stable matter up to total barionic densities of 1.2 fm^-3 are $\Sigma^-$ and
$\Lambda$. The corresponding equations of state are then used to compute
properties of neutron stars such as masses and radii.

</DOC>
<DOC>
<DOCNO> 117801 </DOCNO>
Modeling Galaxy Lenses


  In order to use a gravitational lens to measure the Hubble constant
accurately, it is necessary to derive a reliable model of the lens surface
potential. If the analysis is restricted to the locations and magnifications of
point images, the derived Hubble constant depends upon the class of mass models
used to fit the data. However, when there is extended emission from an Einstein
ring, it may be possible to derive a potential from the observed surface
brightness in a model-independent manner. This procedure is illustrated with
reference to B1608+656. The multi-band images are de-reddened, de-convolved and
de-contaminated so that the luminous matter and the surface brightness contours
in the Einstein ring are both faithfully mapped. This intensity distribution
can then be used to reconstruct the potential. Progress in implementing this
program is reported.
  The observed incidence of multiple-imaged galaxies on the Hubble Deep Fields
is an order of magnitude smaller than naively predicted on the basis of radio
lens surveys, like CLASS, but consistent with the rate computed using surface
photometry of candidate lens galaxies assuming standard mass to light ratios.
In order to resolve this paradox, it is suggested that most galaxy lenses are
located in compact groups.

</DOC>
<DOC>
<DOCNO> 99929 </DOCNO>
On the cohomology ring of the moduli space of Higgs bundles II:


  The moduli space of stable bundles of rank 2 and degree 1 on a Riemann
surface has rational cohomology generated by the so-called universal classes.
The work of Baranovsky, King-Newstead, Siebert-Tian and Zagier provided a
complete set of relations between these classes, expressed in terms of a
recursion in the genus.
  This paper accomplishes the same thing for the non-compact moduli spaces of
Higgs bundles, in the sense of Hitchin and Simpson. There are many more
independent relations than for stable bundles, but in a sense the answer is
simpler, since the formulas are completely explicit, not recursive. The results
of Kirwan on equivariant cohomology for holomorphic circle actions are of key
importance.
  Together, Parts I and II describe the cohomology rings of spaces of Higgs
bundles at essentially the same level of detail as is known for stable bundles.

</DOC>
<DOC>
<DOCNO> 116529 </DOCNO>
Surface waves at the interface between two viscous fluids


  The Surface Green Function Matching analysis (SGFM) is used to study the
normal modes of the interface oscillations between two non-mixed fluids by
considering the difference in their densities and viscosities. The limiting
case of viscous-inviscid system is used for comparison. The role of the
viscosity and the density ratios on the momentum exchange and on the
polarization of the surface modes is analyzed.

</DOC>
<DOC>
<DOCNO> 101417 </DOCNO>
Sextactic points on a simple closed curve


  We give optimal lower bounds for the number of sextactic points on a simple
closed curve in the real projective plane. Sextactic points are after
inflection points the simplest projectively invariant singularities on such
curves. Our method is axiomatic and can be applied in other situations.

</DOC>
<DOC>
<DOCNO> 102492 </DOCNO>
The splitting number can be smaller than the matrix chaos number


  Let chi be the minimum cardinal of a subset of 2^omega that cannot be made
convergent by multiplication with a single Toeplitz matrix. By an application
of creature forcing we show that s<chi is consistent. We thus answer a question
by Vojtas. We give two kinds of models for the strict inequality. The first is
the combination of an aleph_2-iteration of some proper forcing with adding
aleph_1 random reals. The second kind of models is got by adding delta random
reals to a model of MA_{< kappa} for some delta in [aleph_1,kappa). It was a
conjecture of Blass that s=aleph_1<chi=kappa holds in such a model. For the
analysis of the second model we again use the creature forcing from the first
model.

</DOC>
<DOC>
<DOCNO> 120725 </DOCNO>
Evidence from Type Ia Supernovae for an Accelerating Universe


  We review the use of Type Ia supernovae for cosmological distance
determinations. Low-redshift SNe Ia (z < 0.1) demonstrate that the Hubble
expansion is linear, that H_0 = 65 +/- 2 (statistical) km/s/Mpc, and that the
properties of dust in other galaxies are similar to those of dust in the Milky
Way. We find that the light curves of high-redshift (z = 0.3-1) SNe Ia are
stretched in a manner consistent with the expansion of space; similarly, their
spectra exhibit slower temporal evolution (by a factor of 1 + z) than those of
nearby SNe Ia. The luminosity distances of our first set of 16 high-redshift
SNe Ia are, on average, 10-15% farther than expected in a low mass-density
(Omega_M=0.2) universe without a cosmological constant. Preliminary analysis of
our second set of 9 SNe Ia is consistent with this. Our work supports models
with positive cosmological constant and a current acceleration of the
expansion. We address the main potential sources of systematic error; at
present, none of them appears to reconcile the data with Omega_Lambda=0 and q_0
>= 0. The dynamical age of the Universe is estimated to be 14.2 +/- 1.7 Gyr,
consistent with the ages of globular star clusters.

</DOC>
<DOC>
<DOCNO> 119978 </DOCNO>
Theoretical Models of Young Open Star Clusters: Effects of a Gaseous


  We construct a family of semi-analytic models for young open clusters,
including a gaseous component and varying assumptions about the distribution
function for the stellar component. The parameters of these models are informed
by observed open clusters and general theoretical considerations regarding
cluster formation. We use this framework to estimate the fraction of the
stellar component that remains gravitationally bound after the gaseous
component disperses. The remaining stellar fraction is a smooth function of the
star formation efficiency, and depends on the distribution function of the
stars. We calculate the fraction of stars remaining for this class of open
cluster models and provide fitting formulae for representative cases.

</DOC>
<DOC>
<DOCNO> 40575 </DOCNO>
A First Measurement of Low x Low Q^2 Structure Functions in Neutrino


  A new structure function analysis of CCFR deep inelastic nu-N and nubar-N
scattering data is presented for previously unexplored kinematic regions down
to Bjorken x=0.0045 and Q^2=0.3 GeV^2. Comparisons to charged lepton scattering
data from NMC and E665 experiments are made and the behavior of the structure
function F2_nu is studied in the limit Q^2 -> 0.

</DOC>
<DOC>
<DOCNO> 100590 </DOCNO>
Divisorial contractions in dimension three which contract divisors to


  We deal with a divisorial contraction in dimension 3 which contracts its
exceptional divisor to a smooth point. We prove that any such contraction can
be obtained by a suitable weighted blow-up.

</DOC>
<DOC>
<DOCNO> 118121 </DOCNO>
Gamma-Ray Bursts as a Probe of the Very High Redshift Universe


  We show that, if many GRBs are indeed produced by the collapse of massive
stars, GRBs and their afterglows provide a powerful probe of the very high
redshift (z > 5) universe.

</DOC>
<DOC>
<DOCNO> 100800 </DOCNO>
Compactly supported wavelets and representations of the Cuntz relations,


  We show that compactly supported wavelets in L^2(R) of scale N may be
effectively parameterized with a finite set of spin vectors in C^N, and
conversely that every set of spin vectors corresponds to a wavelet. The
characterization is given in terms of irreducible representations of
orthogonality relations defined from multiresolution wavelet filters.

</DOC>
<DOC>
<DOCNO> 174516 </DOCNO>
Proton-proton collisions at production thresholds


  Recent results obtained by the COSY-11 collaboration concerning the
production of eta and eta' mesons in the pp --> pp Meson reaction are
presented. A comparison of the production amplitude for the pi(0), eta and eta'
mesons at the same phase space volume allows to conclude that the proton-eta'
interaction is in the order of, or smaller than, the proton-pi(0) one. A total
cross section determined in a preliminary analysis of the data of elementary
kaon and antikaon production via the pp-->ppK(+)K(-) reaction measured at
excess energy of Q = 17 MeV is reported.

</DOC>
<DOC>
<DOCNO> 170061 </DOCNO>
Entanglement capabilities of non-local Hamiltonians


  We quantify the capability of creating entanglement for a general physical
interaction acting on two qubits. We give a procedure for optimizing the
generation of entanglement. We also show that a Hamiltonian can create more
entanglement if one uses auxiliary systems.

</DOC>
<DOC>
<DOCNO> 68925 </DOCNO>
Present status of the long range component of the nuclear force


  In order to settle the fundamental question whether the nuclear forces
involve the long range components, the S-wave amplitude of the proton-proton
scattering is analysed in search for the extra singularity at $\nu=0$, which
corresponds to the long range force. To facilitate the search, a function,
which is free from the singularities in the neighborhood of $\nu=0$ when all
the interactions are short range, is constructed. The calculation of such a
function from the phase shift data reveals a sharp cusp at $\nu=0$ in
contradiction to the meson theory of the nuclear force. The type of the extra
singularity at $\nu=0$ is close to what is expected in the case of the strong
van der Waals interaction. Physical meanings of the long range force in the
nuclear force are discussed.
 Low energy p-p experiments to confirm directly the strong long range
interaction are also proposed, in which the characteristic interference patten
of the Coulonb and the Van der Waals forces is predicted.

</DOC>
<DOC>
<DOCNO> 8232 </DOCNO>
Magnetic field dependence of the exciton energy in a quantum disk


  The groundstate energy and binding energy of an exciton, confined in a^M
quantum disk, are calculated as a function of an external magnetic field. The
confinement potential is a hard wall of finite height. The diamagnetic shift is
investigated for magnetic fields up to 40$T$. Our results are applied to
$In_{y}Al_{1-y}As/Al_{x}Ga_{1-x}As$ self-assembled quantum dots and very good
agreement with experiments is obtained. Furthermore, we investigated the
influence of the dot size on the diamagnetic shift by changing the disk radius.
The exciton excited states are found as a function of the magnetic field. The
relative angular momentum is not a quantum number and changes with the magnetic
field strength.

</DOC>
<DOC>
<DOCNO> 119898 </DOCNO>
Evidence of thick obscuring matter revealed in the X-ray spectrum of the


  We report the discovery of an unambiguous, substantial low-energy cutoff in
the broad band X-ray spectrum of the radio quasar RXJ1028.6-0844 at a redshift
of 4.276 obtained with the ASCA satellite, which we preferably explained as
indication of excess X-ray absorption. The equivalent hydrogen column density
of the absorbing matter, depending on the redshift and metallicity, ranges from
2.5x10**21 cm**(-2) for local absorption up to 2.1x10**23 cm**(-2) (solar
metallicity) or 1.6x10**24 cm**(-2) (10% solar metallicity) for absorption at
the quasar redshift. Such a value is among the largest found for high-redshift
radio quasars. The absorption, if interpreted as being produced close to the
quasar, may indicate the presence of a remarkably large amount of obscuring
matter in the quasar environment in the early universe. Implications of the
result for the possible origins of the absorbing matter are discussed,
concerning especially galactic intervening matter, cool intracluster gas, and
ambient medium around the quasar jet. The quasar itself has an enormous
apparent luminosity of at least about 2.6x10**47 erg/s (H0=50, q0=0.5) and a
power law photon index of 1.67(+0.07,-0.04) in the 2-50keV band in the source
rest frame.

</DOC>
<DOC>
<DOCNO> 119468 </DOCNO>
Electromagnetic Radiation and Motion of Dust Particle - A Simple Model


  A simple model for motion of dust particle (meteoroid) under the action of
(solar) electromagnetic radiation is presented. The particle of the form of
plane mirror is taken into account and exact analytical results are presented.
As for long-term orbital evolution, particle may spiral outwards the central
body (Sun); initial conditions are important. As a consequence, motion of real
dust particles may differ from that generally considered.

</DOC>
<DOC>
<DOCNO> 99722 </DOCNO>
A Darboux theorem for Hamiltonian operators in the formal calculus of


  We prove a Darboux theorem for formal deformations of Hamiltonian operators
of hydrodynamic type (Dubrovin-Novikov). Not all deformations are equivalent to
the original operator: there is a moduli 2-stack of normal forms.
  The paper utilizes three main concepts:
  1) dg Lie algebras concentrated in degrees [-1,\infty) such as the Schouten
algebra - these give a convenient language for describing deformation problems;
  2) the Deligne 2-groupoid associated to such a dg Lie algebra, which
represents the moduli of formal deformations;
  3) a refined version of the Schouten bracket in the formal calculus of
variations, due to V. O. Soloviev (hep-th/9305133).

</DOC>
<DOC>
<DOCNO> 8522 </DOCNO>
Josephson coupling and plasma resonance in vortex crystal


  We investigate the magnetic field dependence of the plasma resonance
frequency in vortex crystal state. We find that low magnetic field induces a
small correction to the plasma frequency proportional to the field. The slope
of this linear field dependence is directly related to the average distance
between the pancake vortices in the neighboring layers, the wandering length.
This length is determined by both Josephson and magnetic couplings between
layers. At higher fields the plasma frequency is suppressed collectively and is
determined by elastic energy of the vortex lattice. Analyzing experimental
data, we find that (i) the wandering length becomes comparable with the London
penetration depth near T_{c}, (ii) at small melting fields (< 20G) the
wandering length does not change noticeably at the melting transition
demonstrating existence of the line liquid phase in this field range, and (iii)
the self consistent theory of pancake fluctuations describes very well the
field dependence of the Josephson plasma resonance frequency up to the melting
point.

</DOC>
<DOC>
<DOCNO> 70227 </DOCNO>
Axial U(1) dynamics in eta and eta' photoproduction


  We discuss the sensitivity of eta and eta' photoproduction near threshold to
the gluonic OZI breaking parameters in the U_A(1)-extended effective chiral
Lagrangian for low-energy QCD. Our coupled-channels analysis hints at a strong
correlation between the gluon-induced contributions to the eta' mass and the
low-energy pp -> pp eta' reaction and the near-threshold behaviour of the gamma
p -> eta p cross-section.

</DOC>
<DOC>
<DOCNO> 122924 </DOCNO>
The inverse cascade in turbulent dynamos


  The emergence of a large scale magnetic field from randomly forced isotropic
strongly helical flows is discussed in terms of the inverse cascade of magnetic
helicity and the alpha-effect. In simulations of such flows the maximum field
strength exceeds the equipartition field strength for large scale separation.
However, helicity conservation controls the speed at which this final state is
reached. In the presence of open boundaries magnetic helicity fluxes out of the
domain are possible. This reduces the timescales of the field growth, but it
also tends to reduce the maximum attainable field strength.

</DOC>
<DOC>
<DOCNO> 13966 </DOCNO>
Simulations of liquid crystals in Poiseuille flow


  Lattice Boltzmann simulations are used to explore the behavior of liquid
crystals subject to Poiseuille flow. In the nematic regime at low shear rates
we find two possible steady state configurations of the director field. The
selected state depends on both the shear rate and the history of the sample.
For both director configurations there is clear evidence of shear-thinning, a
decrease in the viscosity with increasing shear rate. Moreover, at very high
shear rates or when the order parameter is large, the system transforms to a
log-rolling state with boundary layers that may exhibit oscillatory behavior.

</DOC>
<DOC>
<DOCNO> 71369 </DOCNO>
Quantum (In)Stability of a Brane-World AdS$\bf_5$ Universe at Nonzero


  We consider the quantum effects of bulk matter (scalars, spinors) in the
Randall-Sundrum AdS$_5$ brane-world at nonzero temperature. The thermodynamic
energy (modulus potential) is evaluated at low and high temperatures. This
potential has an extremum which could be a minimum in some cases (for example,
for a single fermion). That suggests a new dynamical mechanism to stabilize the
thermal AdS$_5$ brane-world. It is shown that the brane separation required to
solve the hierarchy scale problem may occur at a quite low temperature. A
natural generalization in terms of the AdS/CFT correspondence (through the
supergravity thermal contribution) is also possible.

</DOC>
<DOC>
<DOCNO> 152291 </DOCNO>
Logarithmic operators in SL(2, R) WZNW model, Singletons and


  We discuss the role of singletons in SL(2, R) WZNW model and AdS_3/LCFT_2
correspondence.

</DOC>
<DOC>
<DOCNO> 121258 </DOCNO>
Hierarchical Clustering and Active Galaxies


  The growth of Super Massive Black Holes and the parallel development of
activity in galactic nuclei are implemented in an analytic code of hierarchical
clustering. The evolution of the luminosity function of quasars and AGN will be
computed with special attention paid to the connection between quasars and
Seyfert galaxies. One of the major interests of the model is the parallel study
of quasar formation and evolution and the History of Star Formation.

</DOC>
<DOC>
<DOCNO> 123062 </DOCNO>
In search for the oldest star forming regions in Holmberg II


  We present an X-ray study of the irregular dwarf galaxy Holmberg II based on
deep ROSAT PSPC observations. Holmberg II is one of the most famous examples of
an irregular dwarf galaxy with a disrupted interstellar medium (ISM): expanding
HI holes are present across the entire face of the galaxy. Huge HI cavities of
kpc extent are found even outside current starforming regions. We search for
faint X-ray sources (stellar end points as well as hot gas), touching the
limits of the ROSAT PSPC detector and link the newly detected X-ray sources to
features detected in other wavelengths. Using an X-ray hardness ratio
color-color diagram we show that it is possible to differentiate between
thermal plasma and power-law X-ray spectra, which helps to track down the
physical nature of the individual sources.

</DOC>
<DOC>
<DOCNO> 179011 </DOCNO>
Phase Shifts and Mixing Parameters for Elastic Proton-Deuteron


  The eigenphase shifts and mixing parameters for elastic p-d scattering below
the deuteron-breakup threshold are calculated for the AV14 two-body potential
using two different numerical methods. The excellent agreement confirms that it
is possible to perform accurate numerical studies of p-d scattering as well as
n-d scattering for low energies. The numerical results can be considered as
benchmarks for future calculations.

</DOC>
<DOC>
<DOCNO> 151314 </DOCNO>
Matter Coupled F(4) Supergravity and the AdS_6/CFT_5 Correspondence


  F(4) supergravity, the gauge theory of the exceptional six-dimensional
Anti-de Sitter superalgebra, is coupled to an arbitrary number of vector
multiplets whose scalar components parametrize the quaternionic manifold
$SO(4,n)/SO(4)\times SO(n)$. By gauging the compact subgroup $SU(2)_d \otimes
\cG$, where SU(2)_d is the diagonal subgroup of $SO(4)\simeq SU(2)_L\otimes
SU(2)_R$ (the R-symmetry group of six-dimensional Poincar\'e supergravity) and
$\cG$ is a compact group such that $dim\cG = n$, we compute the scalar
potential which, besides the gauge coupling constants, also depends in non
trivial way on the parameter m associated to a massive 2-form $B_{\mu\nu}$ of
the gravitational multiplet. The potential admits an AdS background for g=3m,
as the pure F(4)-supergravity. We compute the scalar squared masses (which are
all negative) and retrieve the results dictated by AdS_6/CFT_5 correspondence
from the conformal dimensions of boundary operators. The boundary F(4)
superconformal fields are realized in terms of a singleton superfield
(hypermultiplet) in harmonic superspace with flag manifold SU(2)/U(1)=S^2. We
analize the spectrum of short representations in terms of superconformal
primaries and predict general features of the K-K specrum of massive type IIA
supergravity compactified on warped $AdS_6\otimes S^4$.

</DOC>
<DOC>
<DOCNO> 13452 </DOCNO>
A nonlinear differential approach to the Saffman-Taylor finger


  Nonlinear time-dependent differential equations for the Hele-Shaw,
Saffman-Taylor problem are derived. The equations are obtained using a
separable ansatz expansion for the stream function of the displaced fluid
obeying a Darcian flow. Suitable boundary conditions on the stream function,
provide a potential term for the nonlinear equation. The limits for the finger
widths derived from the potential and boundary conditions are
$1>\lambda>\frac{1}{\sqrt{5}}$, in units of half the width of the Hele-Shaw
cell, in accordance with observation. Stationary solutions with no free
phenomenological parameters are found numerically. The dependence of asymptotic
finger width on the physical parameters of the cell compares satisfactorily
with experiment. The correct dispersion relation for the instabilities is
obtained from the time dependent equation.

</DOC>
<DOC>
<DOCNO> 80757 </DOCNO>
The Simple Center Projection of SU(2) Gauge Theory


  We consider the SU(2) lattice gauge model. We propose a new gauge invariant
definition of center projection, which we call the Simple Center Projection. We
demonstrate the center dominance, i.e., the coincidence of the projected
potential with the full potential up to the mass renormalization term at low
energies. We also consider the center vortices and the center monopoles ({\em
nexuses}). It turns out that the behavior of such objects qualitatively
coincides with the behavior of the vortices and monopoles in the Maximal Center
gauge. The connection of the condensation of nexuses with the dual
superconductor theory is discussed. Numerically the procedure of extracting the
center vortices proposed in this paper is much simpler than the usual Maximal
Center Projection.

</DOC>
<DOC>
<DOCNO> 40450 </DOCNO>
Can the Lambda pi scattering phase shifts be large?


  Motivated by the presence of nearby thresholds in other baryon-meson channels
with I=1 and S=-1, we investigate whether the Lambda pi scattering phase shifts
at a center-of-mass energy equal to the Xi mass could be larger than suggested
by lowest-order chiral perturbation theory. Within a coupled-channel K-matrix
approach, we find that the S-wave phase shift could be as large as -7 degrees.

</DOC>
<DOC>
<DOCNO> 102663 </DOCNO>
Propagation of infinitely narrow delta-solitons


  We construct a definition of the weak solution to KdV type equations with
small dispersion admitting the zero dispersion limit for soliton-like
solutions. Using this definition, we obtain a system of equations (the limit
problem as the dispersion tends to zero) that describes the soliton dynamics.

</DOC>
<DOC>
<DOCNO> 170589 </DOCNO>
Polynomial procedure of avoiding multiqubit errors arising due to


  Recently proposed implementations of quantum computer suffer from unavoidable
interaction between quantum bits depending upon data being written in them.
Novel procedure of avoiding multiqubit errors arising due to uncontrollable
qubit-qubit interaction by using addititonal intermediate qubits is proposed.
It is shown that the scheme requires only polynomial increase in number of
qubits and algorithmic steps.

</DOC>
<DOC>
<DOCNO> 152304 </DOCNO>
Off-shell tachyon amplitudes: analyticity and projective invariance


  We compute off-shell three- and four-tachyon amplitudes at tree level by
using a prescription based on the requirement of projective invariance. In
particular we show that the off-shell four-tachyon amplitude can be put in the
same form as the corresponding on-shell one, exhibiting therefore the same
analyticity properties. This is shown both for the bosonic and the fermionic
string. The result obtained in the latter case can be extended to the off-shell
four-tachyon amplitude in type 0 theory.

</DOC>
<DOC>
<DOCNO> 11956 </DOCNO>
Toroidal optical dipole traps for atomic Bose-Einstein condensates using


  We theoretically investigate the use of red-detuned Laguerre-Gaussian (LG)
laser beams of varying azimuthal mode index for producing toroidal optical
dipole traps in two-dimensional atomic Bose-Einstein condensates. Higher-order
LG beams provide deeper potential wells and tighter confinement for a fixed
toroid radius and laser power. Numerical simulations of the loading of the
toroidal trap from a variety of initial conditions is also given.

</DOC>
<DOC>
<DOCNO> 170521 </DOCNO>
Complex Calogero model with real energies


  We show that and how PT symmetry (interpreted as a "weakened Hermiticity")
can be extended to the exactly solvable two- and three-particle Calogero model.

</DOC>
<DOC>
<DOCNO> 117784 </DOCNO>
Relations Between Timing Features and Colors in the X-Ray Binary 4U


  We study the correlations between timing and X-ray spectral properties in the
low mass X-ray binary 4U 0614+09 using a large (265-ks) data set obtained with
the Rossi X-ray Timing Explorer. We find strong quasi-periodic oscillations
(QPOs) of the X-ray flux, like the kilohertz QPOs in many other X-ray binaries
with accreting neutron stars, with frequencies ranging from 1329 Hz down to 418
Hz and, perhaps, as low as 153 Hz. We report the highest frequency QPO yet from
any low mass X-ray binary at 1329+-4 Hz, which has implications for neutron
star structure. This QPO has a 3.5-sigma single-trial significance, for an
estimated 40 trials the significance is 2.4-sigma. Besides the kilohertz QPOs,
the Fourier power spectra show four additional components: high frequency noise
(HFN), described by a broken power-law with a break frequency between 0.7 and
45 Hz, very low frequency noise (VLFN), which is fitted as a power-law below 1
Hz, and two broad Lorentzians with centroid frequencies varying from 6 to 38 Hz
and 97 to 158 Hz, respectively. We find strong correlations between the
frequencies of the kilohertz QPOs, the frequency of the 6 to 38 Hz broad
Lorentzian, the break frequency of the HFN, the strength of both the HFN and
the VLFN and the position of the source in the hard X-ray color vs. intensity
diagram. The frequency of the 97 to 158 Hz Lorentzian does not correlate with
these parameters. We also find that the relation between power density and
break frequency of the HFN is similar to that established for black hole
candidates in the low state. We suggest that the changing mass accretion rate
is responsible for the correlated changes in all these parameters.

</DOC>
<DOC>
<DOCNO> 13371 </DOCNO>
Exciton-phonon droplets with Bose-Einstein condensate: transport and


  We discuss the possibility for a moving droplet of excitons and phonons to
form a coherent state inside the packet. We describe such an inhomogeneous
state in terms of Bose-Einstein condensation and prescribe it a macroscopic
wave function. Existence and, thus, coherency of the Bose-core inside the
droplet can be checked experimentally by letting two moving packets to
interact.

</DOC>
<DOC>
<DOCNO> 120465 </DOCNO>
Hard synchrotron BL Lacs: the case of 1ES 1101-232


  The bright X-ray selected BL Lac object 1ES1101--232 shows a flat X-ray
spectrum, making it detectable with high statistics over the wide BeppoSAX
energy range. We have observed it in two different epochs with BeppoSAX, and
found a variation of the flux of about 30% that can be explained by a change in
the spectral index above the synchrotron peak. We present here the data and
infer limits on the strength of the magnetic field based on models of emission
for High-frequency peaked BL Lacs.

</DOC>
<DOC>
<DOCNO> 99377 </DOCNO>
Optimal Prediction of Stiff Oscillatory Mechanics


  We consider many-body problems in classical mechanics where a wide range of
time scales limits what can be computed. We apply the method of optimal
prediction to obtain equations which are easier to solve numerically. We
demonstrate by examples that optimal prediction can reduce the amount of
computation needed to obtain a solution by several orders of magnitude.

</DOC>
<DOC>
<DOCNO> 122524 </DOCNO>
Stars of the Draco Dwarf Spheroidal Galaxy Beyond its Measured Tidal


  We report R- and V-band photometry derived from CCD imaging for objects in
nine fields in and around the Draco dwarf spheroidal galaxy. The most distant
fields are about 1.3 degrees from the center. We use these data to search for
Draco stars outside of its measured tidal boundary. The search involves three
methods: 1) Plotting color-magnitude diagrams for individual fields, for
sections of fields, and for combined fields and sections. A color-magnitude
diagram can reveal a population of Draco stars by the presence of the expected
principal sequences. 2) Measuring field-to-field fluctuations and 3) measuring
intra-field fluctuations in the surface density of objects located near the
Draco principal sequences in the color-magnitude diagram. We find evidence for
the presence of Draco stars immediately beyond the measured tidal boundary of
Draco and place an upper limit on the number of such stars in more distant
fields that lie close to the extension of its major axis. The best evidence is
the presence of the Draco principal sequences in the color-magnitude diagram
for some combined fields and sections of fields. The measurements of the
field-to-field fluctuations in the stellar surface density confirm this result.

</DOC>
<DOC>
<DOCNO> 170584 </DOCNO>
Grover's quantum search algorithm


  This paper is a written version of a one hour lecture given on Lov Grover's
database search algorithm.
  Table Of Contents
  1 ... Problem Definition
  2 ... The quantum mechanical perspective
  3 ... Properties of the inversion I_|psi>
  4 ... The method in Lov's "madness"
  5 ... Summary of Grover's algorithm
  6 ... An example of Grover's algorithm
  References

</DOC>
<DOC>
<DOCNO> 150659 </DOCNO>
Orientifolds, M-Theory, and the ABCD's of the Enhancon


  Supergravity solutions related to large N SU(N) pure gauge theories with
eight supercharges have recently been shown to give rise to an ``enhancon'', a
new type of hypersurface made of D-branes. We show that enhancons also arise in
similar situations pertaining to SO(2N+1), USp(2N) and SO(2N) gauge theories,
using orientifolds. Enhancons therefore appear to come in types A, B, C, and D.
The latter three differ globally from type A by having an extra Z_2
identification, and are distinguished locally by their subleading behaviour in
large N. We focus mainly on 2+1 dimensional gauge theory, where a relation to
M-theory and the Atiyah-Hitchin and Taub-NUT manifolds enables the construction
of the smooth supergravity solution and the study of some of the 1/N
corrections. The role of the enhancon in eleven dimensional supergravity is
also uncovered. There is a close relation to certain multi-monopole moduli
space problems.

</DOC>
<DOC>
<DOCNO> 120229 </DOCNO>
The ISO-LWS map of the Serpens cloud core: I. The SEDs of the IR/SMM


  ISO-LWS mapping observations of the Serpens molecular cloud core are
presented. The spectral range is 50 - 200 micron and the map size is 8' X 8'.
These observations suffer from severe source confusion at FIR wavelengths and
we employ a Maximum Likelihood Method for the spectro-spatial deconvolution.
The strong and fairly isolated source SMM1 FIRS1 presented a test case, whose
modelled spectral energy distribution (SED), within observational errors, is
identical to the observed one. The model results for the other infrared and
submillimetre sources are therefore likely to represent their correct SEDs.
Simulations demonstrating the reliability and potential of the developed method
support this view. For the majority of sources the peak of the SEDs is found
within the spectral range of the LWS and derived temperatures are generally
higher (>30K) than have been found by earlier deconvolution attempts using IRAS
data. SMM sizes are found to be only a few arcsec in diameter. In addition, the
SMMs are generally optically thick even at LWS wavelengths. Self-consistent
radiative transfer calculations indicates that the SMMs are optically thick out
to even longer wavelengths. Models were calculated for five sources, for which
sufficient data were available, viz. SMM 1, 2, 3, 4 and 9. These models are
optically thick out to millimetre wavelengths (wavelength of unit optical depth
900 to 1400 micron). Envelope masses for these SMMs are in the range 2-6 Msun,
which is of course considerably more massive than estimates based on the
optically thin assumption. The luminosities are in the range 10-70 Lsun,
suggesting the formation of low-mass to intermediate mass stars, so that the
existence of such massive envelopes argues for extreme youth of the SMMs in the
Serpens cloud core.

</DOC>
<DOC>
<DOCNO> 119179 </DOCNO>
Pulsar optical observation with the Very Large Telescope


  Optical data in the V-band gathered with the 8.2m ESO Very Large Telescope
(VLT) at the radio interferometric position of PSR 1706-44 are presented. The
pulsar is close to a bright star in projection and was not detected. The pulsar
magnitude limit must be fainter than V=24.5 for a distance of $\leq$ 2\farcs0
from the bright star. In the outer gap model for an aligned rotor the optical
flux should scale with the gamma-ray flux. For pulsars which emit pulsed
gamma-rays but are not detected in the optical bands, the synchrotron cutoff
frequency for the tertiary photons must be well below the optical frequencies
and the magnetic and spin axes may be misaligned.

</DOC>
<DOC>
<DOCNO> 102217 </DOCNO>
The moduli space of rational elliptic surfaces


  We show that the moduli space of rational elliptic surfaces admitting a
section is locally a complex hyperbolic variety of dimension eight. We compare
its Satake-Baily-Borel compactification with a compactification obtained by
means of geometric invariant theory, considered by Miranda.

</DOC>
<DOC>
<DOCNO> 40319 </DOCNO>
Top Physics from Run 1 and Run 2 Prospects at CDF


  We present a summary of top quark physics results from Run 1 at CDF using the
Run 1 data sample of 106 pb$^{-1}$. In addition to the precursory measurements
of the top quark mass and $\ttbar$ cross section, we have performed a number of
other analyses which test the consistency of the $\ttbar$ data sample with the
standard model (SM). Deviations from SM expectations could provide hints for
new physics. We find that the data are consistent with the SM. While the Run 1
data are statistically limited, we have shown that the systematic uncertainties
are under control and thus have layed the groundwork for higher precision tests
of the SM in Run 2. This report describes the Run 1 top quark analyses and
expectations and prospects for top quark measurements in Run 2.

</DOC>
<DOC>
<DOCNO> 99716 </DOCNO>
D-branes, B-fields and twisted K-theory


  In this note we propose that D-brane charges, in the presence of a
topologically non-trivial B-field, are classified by the K-theory of an
infinite dimensional C^*-algebra. In the case of B-fields whose curvature is
pure torsion our description is shown to coincide with that of Witten.

</DOC>
<DOC>
<DOCNO> 178684 </DOCNO>
Photons from Ultra-Relativistic Heavy Ion Collisions


  It is believed that a novel state of matter - Quark Gluon Plasma (QGP) will
be transiently produced if normal hadronic matter is subjected to sufficiently
high temperature and/or density. We have investigated the possibility of QGP
formation in the ultra-relativistic collisions of heavy ions through the
electromagnetic probes - photons and dileptons. The formulation of the real and
virtual photon production rate from strongly interacting matter is studied in
the framework of Thermal Field Theory. Since signals from the QGP will pick up
large backgrounds from hadronic matter we have performed a detailed study of
the changes in the hadronic properties induced by temperature within the ambit
of the Quantum Hadrodynamic model, gauged linear and non-linear sigma models,
hidden local symmetry approach and QCD sum rule approach. The possibility of
observing the direct thermal photons and lepton pairs from quark gluon plasma
has been contrasted with that from hot hadronic matter with and without medium
effects for various mass variation scenarios. The effects of medium induced
modifications have also been incorporated in the evolution dynamics through the
equation of state. We find that the in-medium effects on the hadronic
properties in the framework of the Quantum Hadrodynamic model, Brown-Rho
scaling and Nambu scaling scenarios are conspicuously visible through the low
invariant mass distribution of dileptons and transverse momentum spectra of
photons. We have compared our evaluation of the photon and dilepton spectra
with experimental data obtained by the WA80, WA98 and CERES Collaborations in
the heavy ion experiments performed at the CERN SPS. Predictions of
electromagnetic spectra for RHIC energies have also been made.

</DOC>
<DOC>
<DOCNO> 9296 </DOCNO>
Electronic structure of NiS_{1-x}Se_x


  We investigate the electronic structure of the metallic NiS$_{1-x}$Se$_x$
system using various electron spectroscopic techniques. The band structure
results do not describe the details of the spectral features in the
experimental spectrum, even for this paramagnetic metallic phase. However, a
parameterized many-body multi-band model is found to be successful in
describing the Ni~2$p$ core level and valence band, within the same model. The
asymmetric line shape as well as the weak intensity feature in the Ni~2$p$ core
level spectrum has been ascribed to extrinsic loss processes in the system. The
presence of satellite features in the valence band spectrum shows the existence
of the lower Hubbard band, deep inside the $pd$ metallic regime, consistent
with the predictions of the dynamical mean field theory.

</DOC>
<DOC>
<DOCNO> 119757 </DOCNO>
Removal of the calcium underabundance in cool metal rich Galactic disk


  An apparent Ca underabundance for cool metal rich disk dwarfs was derived by
Feltzing & Gustafsson (1998, A&AS, 129, 237). This was suggested to be a NLTE
effect, following the prediction by Drake (1991, MNRAS, 251, 369). New NLTE
calculations with MARCS atmospheres and opacities (Thor\'en, P., 2000, A&A, in
preparation) show that deviations from LTE are very small and can not explain
the underabundance. It is shown that the underabundance was primarily due to
erroneously calculated atomic line broadening parameters (van der Waals
broadening). Part of the underabundance was also due to the decision not to
change photometrically determined stellar parameters to satisfy the Fe I
excitation balance.

</DOC>
<DOC>
<DOCNO> 116444 </DOCNO>
Comparision of direct and Fourier space techniques in time-dependent


  Several techniques have appeared in the literatuare to solve the equations of
time-dependent density functional theory. We compare the efficiency of
different methods based on mesh representations of the wave function (direct
and Fourier space), taking as a test case the calculation of the surface
plasmon in the cluster Na_8. For smaller systems, the methods have comparable
efficiency. For large systems the direct time method has a decided advantage in
computer storage requirements. It is also more economical on arithmetic
operations, but is not as suited for parallel computing as the methods based on
a frequency representation.

</DOC>
<DOC>
<DOCNO> 169884 </DOCNO>
Quantum Feedback for Protection of Schroedinger-cat states


  We review the use of quantum feedback for combatting the decoherence of
Schroedinger-cat-like states in electromagnetic cavities, with special emphasys
on our recent proposal of an automatic mechanism based on the injection of
appropriately prepared ``probe'' and ``feedback'' Rydberg atoms. In the latter
scheme, the information transmission from the probe to the feedback atom is
directly mediated by a second auxiliary cavity. The detection efficiency for
the probe atom is no longer a critical parameter, and the decoherence time of
the linear superposition state can be significantly increased using presently
available technology.

</DOC>
<DOC>
<DOCNO> 102530 </DOCNO>
Characteristically nilpotent Lie algebras : a survey


  We review the known results about characteristically nilpotent complex Lie
algebras, as well as we comment recent developements in the theory.

</DOC>
<DOC>
<DOCNO> 122547 </DOCNO>
The JVAS/CLASS 6'' to 15'' Lens Search


  We present the strategy and status of a gravitational lens search for
multiple imaging with angular separations between 6'' and 15'' with the
combined JVAS and CLASS data set of ~15,000 flat-spectrum radio sources.
Currently all but one lens candidate have been rejected.

</DOC>
<DOC>
<DOCNO> 69383 </DOCNO>
Strangeness and Hadron Structure


  The nucleon wave function may contain a significant component of ssbar pairs,
according to several measurements including the pi-nucleon sigma term, charm
production and polarization effects in deep-inelastic scattering. In addition,
there are excesses of phi production in LEAR and other experiments, above
predictions based the naive Okubo-Zweig-Iizuka rule, that may be explained if
the nucleon wave function contains a polarized ssbar component. This model also
reproduces qualitatively data on Lambda polarization in deep-inelastic neutrino
scattering. The strange component of the proton is potentially important for
other physics, such as the search for astrophysical dark matter.

</DOC>
<DOC>
<DOCNO> 174558 </DOCNO>
Neutron-Proton Differential Flow as a Probe of Isospin-Dependence of


  The neutron-proton differential flow is shown to be a very useful probe of
the isospin-dependence of the nuclear equation of state (EOS). This novel
approach utilizes constructively both the isospin fractionation and the nuclear
collective flow as well as their sensitivities to the isospin-dependence of the
nuclear EOS. It also avoids effectively uncertainties associated with other
dynamical ingredients of heavy-ion reactions at intermediate energies.

</DOC>
<DOC>
<DOCNO> 101532 </DOCNO>
Spin-Orbital Motion: Symmetry and Dynamics


  We present the applications of variational--wavelet approach to nonlinear
(rational) model for spin-orbital motion: orbital dynamics and Thomas-BMT
equations for classical spin vector. We represent the solution of this
dynamical system in framework of periodical wavelets via variational approach
and multiresolution.

</DOC>
<DOC>
<DOCNO> 152322 </DOCNO>
Seiberg-Witten theory and duality in integrable systems


  These lectures are devoted to the low energy limit of \N2 SUSY gauge
theories, which is described in terms of integrable systems. A special emphasis
is on a duality that naturally acts on these integrable systems. The duality
turns out to be an effective tool in constructing the double elliptic
integrable system which describes the six-dimensional Seiberg-Witten theory. At
the same time, it implies a series of relations between other Seiberg-Witten
systems.

</DOC>
<DOC>
<DOCNO> 11135 </DOCNO>
Force-Induced Melting and Thermal Melting of a Double-Stranded


  As a prototype of systems bearing a localization-delocalization transition,
the strand-separation (melting) process in a double-stranded biopolymer is
studied by a mapping to a quantum-mechanical problem with short-ranged
potentials. Both the bounded and the extensive eigenmodes of the corresponding
Schrodinger equation are considered and exact expressions for the
configurational partition function and free energy are obtained. The
force-induced melting is a first order phase transition process, while the
thermal melting is found to be second order. Some scaling exponents governing
thermal melting are given.

</DOC>
<DOC>
<DOCNO> 72182 </DOCNO>
CP asymmetry in the Higgs decay into the top pair due to the stop mixing


  We investigate a potentially large CP violating asymmetry in the decay of a
neutral scalar or pseudoscalar Higgs boson into the top-anti-top pair. The
source of the CP nonconservation is the complex mixing in the (left-right) stop
sector. One of the interesting consequence is the different rates of the Higgs
boson decays into CP conjugate polarized states.

</DOC>
<DOC>
<DOCNO> 120607 </DOCNO>
Compton-Thick X-ray Absorption in the Seyfert Galaxies Tololo 0109-383


  We present analyses of the ASCA X-ray spectra of two Seyfert galaxies, Tololo
0109-383 and ESO 138-G1. In both cases, spectral fitting reveals two
statistically acceptable continuum models: Compton reflection and partial
covering. Both spectra have strong iron K-alpha lines, with equivalent widths
greater than 1.5 keV. These large equivalent widths are suggestive of heavier
obscuration than that directly indicated by the partial-covering models
(approximately 2 x 10^23 cm^-2), with the actual column densities being
`Compton-thick' (i.e. N_H > 1.5 x 10^24 cm^-2). We use the hard X-ray/[O III]
flux correlation for Seyferts and data from the literature to provide
additional support for this hypothesis. Since Tololo 0109-383 is known to have
optical type 1 characteristics such as broad Balmer line components and Fe II
emission, this result marks it as a notable object.

</DOC>
<DOC>
<DOCNO> 85483 </DOCNO>
Black Hole in Higher Curvature Gravity and AdS/CFT Correspondence


  The classical central charge for the higher curvature gravity in 3-dimensions
is calculated using the Legendre transformation method. The statistical entropy
of BTZ black hole is derived by the Cardy's formula and the result completely
coincides with the Iyer-Wald formula for the geometrical entropy. This
coincidence suggests the generalized AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 102653 </DOCNO>
Lefschetz pencils and the canonical class for symplectic 4-manifolds


  We present a new proof of a result due to Taubes: if X is a closed symplectic
four-manifold with b_+(X) > 1+b_1(X) and with some positive multiple of the
symplectic form a rational class, then the Poincare dual of the canonical class
of X may be represented by an embedded symplectic submanifold. The result
builds on the existence of Lefschetz pencils on symplectic four-manifolds. We
approach the topological problem of constructing submanifolds with locally
positive intersections via almost complex geometry. The crux of the argument is
that a Gromov invariant counting pseudoholomorphic sections of an associated
bundle of symmetric products is non-zero.

</DOC>
<DOC>
<DOCNO> 121344 </DOCNO>
High Energy Gamma Rays


  This article reviews the present status of high energy gamma-ray astronomy at
energies above 30 MeV. Observations in the past decade using both space- and
ground-based experiments have been primarily responsible for giving a
tremendous boost to our knowledge of the high energy Universe. High energy
gamma-rays have been detected from a wide range of Galactic and extragalactic
astrophysical sources, such as gamma-ray bursters, pulsars, and active
galaxies. These observations have established high energy gamma-ray astronomy
as a vital and exciting field, that has a bright future. This review summarizes
the experimental techniques, observations and results obtained with recent
experiments, and concludes with a short description of future prospects.

</DOC>
<DOC>
<DOCNO> 152637 </DOCNO>
Supersymmetry of Green-Schwarz Superstring and Matrix String Theory


  We study the dynamics of Green-Schwarz superstring on the gravitational wave
background corresponding to the Matrix string theory and the supersymmetry
transformation rules of the superstring. The dynamics is obtained in the
light-cone formulation and is shown to agree with that derived from the Matrix
string theory. The supersymmetry structure has the corrections due to the
effect of the background and is identified with that of the low energy one-loop
effective action of Matrix string theory in two superstring background in the
weak string coupling limit.

</DOC>
<DOC>
<DOCNO> 122400 </DOCNO>
XMM-Newton observations of M87 and Its X-Ray Halo


  We report performance verification observations of the giant elliptical
galaxy M87 in the Virgo Cluster with the MOS, pn, and optical monitor
instruments on board of XMM-Newton. With the energy sensitive imaging
instruments MOS and pn we obtain the first spatially constrained X-ray spectra
of the nucleus and the jet of the galaxy. The good photon statistics of the pn
and MOS allow a detailed analysis of the radial temperature and abundance
distribution of 6 elements. The data provide no indication of a
multi-temperature structure for radii less than 2 arcmin. An apparent sharp
metal abundance drop deduced for the regions inside this radius is probably due
to resonant line scattering.

</DOC>
<DOC>
<DOCNO> 151180 </DOCNO>
On string theory in AdS_3 backgrounds


  We discuss the string theory on AdS_3. In the first half of this talk, we
review the SL(2,R) and the SL(2,C)/SU(2) WZW models which describe the strings
on the Lorentzian and Euclidean AdS_3 without RR backgrounds, respectively. An
emphasis is put on the fundamental issues such as the unitarity, the modular
invariance and the closure of the OPE. In the second half, we discuss some
attempts at clarifying such problems. In particular, we discuss the modular
invariance of the SL(2,R) WZW model and the calculation of the correlation
functions of the SL(2,C)/SU(2) WZW model using the path-integral approach.

</DOC>
<DOC>
<DOCNO> 100889 </DOCNO>
Nahm Transform For Periodic Monopoles And N=2 Super Yang-Mills Theory


  We study Bogomolny equations on $R^2\times S^1$. Although they do not admit
nontrivial finite-energy solutions, we show that there are interesting
infinite-energy solutions with Higgs field growing logarithmically at infinity.
We call these solutions periodic monopoles. Using Nahm transform, we show that
periodic monopoles are in one-to-one correspondence with solutions of Hitchin
equations on a cylinder with Higgs field growing exponentially at infinity. The
moduli spaces of periodic monopoles belong to a novel class of hyperk\"ahler
manifolds and have applications to quantum gauge theory and string theory. For
example, we show that the moduli space of $k$ periodic monopoles provides the
exact solution of ${\cal N}=2$ super Yang-Mills theory with gauge group $SU(k)$
compactified on a circle of arbitrary radius.

</DOC>
<DOC>
<DOCNO> 122323 </DOCNO>
The Quintessential CMB, Past & Future


  The past, present and future of cosmic microwave background (CMB) anisotropy
research is discussed, with emphasis on the Boomerang and Maxima balloon
experiments. These data are combined with large scale structure (LSS)
information and high redshift supernova (SN1) observations to explore the
inflation-based cosmic structure formation paradigm. Here we primarily focus on
a simplified inflation parameter set, {omega_b,omega_{cdm},Omega_{tot},
Omega_Q,w_Q, n_s,tau_C, sigma_8}. After marginalizing over the other cosmic and
experimental variables, we find the current CMB+LSS+SN1 data gives
Omega_{tot}=1.04\pm 0.05, consistent with (non-baroque) inflation theory.
Restricting to Omega_{tot}=1, we find a nearly scale invariant spectrum, n_s
=1.03 \pm 0.07. The CDM density, omega_{cdm}=0.17\pm 0.02, is in the expected
range, but the baryon density, omega_b=0.030\pm 0.004, is slightly larger than
the current nucleosynthesis estimate. Substantial dark energy is inferred,
Omega_Q\approx 0.68\pm 0.05, and CMB+LSS Omega_Q values are compatible with the
independent SN1 estimates. The dark energy equation of state, parameterized by
a quintessence-field pressure-to-density ratio w_Q, is not well determined by
CMB+LSS (w_Q<-0.3 at 95%CL), but when combined with SN1 the resulting w_Q<-0.7
limit is quite consistent with the w_Q=-1 cosmological constant case. Though
forecasts of statistical errors on parameters for current and future
experiments are rosy, rooting out systematic errors will define the true
progress.

</DOC>
<DOC>
<DOCNO> 99950 </DOCNO>
Quantum Strata of Coadjoint Orbits


  In this paper we construct quantum analogs of strata of coadjoint orbits and
describe their representations. This kind objects play an important role in
describing quantum groups as repeated extensions of quantum strata.

</DOC>
<DOC>
<DOCNO> 99784 </DOCNO>
Orthogonal Polynomials and Generalized Oscillator Algebras


  For any orthogonal polynomials system on real line we construct an
appropriate oscillator algebra such that the polynomials make up the
eigenfunctions system of the oscillator hamiltonian. The general scheme is
divided into two types: a symmetric scheme and a non-symmetric scheme. The
general approach is illustrated by the examples of the classical orthogonal
polynomials: Hermite, Jacobi and Laguerre polynomials. For these polynomials we
obtain the explicit form of the hamiltonians, the energy levels and the
explicit form of the impulse operators.

</DOC>
<DOC>
<DOCNO> 7640 </DOCNO>
Electron-phonon interaction in C70


  The matrix elements of the deformation potential of C$_{70}$ are calculated
by means of a simple, yet accurate solution of the electron-phonon coupling
problem in fullerenes, based on a parametrization of the ground state
electronic density of the system in terms of $sp^{2+x}$ hybridized orbitals.
The value of the calculated dimensionless total electron-phonon coupling
constant is $\lambda\approx0.1$, an order of magnitude smaller than in
C$_{60}$, consistent with the lack of a superconducting phase transition in
C$_{70}$A$_3$ fullerite, and in overall agreement with measurements of the
broadening of Raman peaks in C$_{70}$K$_4$. We also calculate the photoemission
cross section of C$_{70}^-$, which is found to display less structure than that
associated with C$_{60}^-$, in overall agreement with the experimental
findings.

</DOC>
<DOC>
<DOCNO> 117972 </DOCNO>
Non-LTE Effects in Berylium Abundances


  In this work we analyze the beryllium-iron chemical diagram from the point of
view of non-LTE effects. Be abundances were re-calculated by considering
non-LTE corrections in ionization equilibrium (logg) and Fe abundances
([Fe/H]). These corrections seem do not affect the linear relation between
Be-Fe for metal-poor stars already found in the literature for LTE derived
abundances.

</DOC>
<DOC>
<DOCNO> 101810 </DOCNO>
An L^2-Index Theorem for Dirac Operators on S^1 * R^3


  An expression is found for the $L^2$-index of a Dirac operator coupled to a
connection on a $U_n$ vector bundle over $S^1\times{\mathbb R}^3$. Boundary
conditions for the connection are given which ensure the coupled Dirac operator
is Fredholm. Callias' index theorem is used to calculate the index when the
connection is independent of the coordinate on $S^1$. An excision theorem due
to Gromov, Lawson, and Anghel reduces the index theorem to this special case.
The index formula can be expressed using the adiabatic limit of the
$\eta$-invariant of a Dirac operator canonically associated to the boundary. An
application of the theorem is to count the zero modes of the Dirac operator in
the background of a caloron (periodic instanton).

</DOC>
<DOC>
<DOCNO> 9962 </DOCNO>
Random replicators with high-order interactions


  We use tools of the equilibrium statistical mechanics of disordered systems
to study analytically the statistical properties of an ecosystem composed of N
species interacting via random, Gaussian interactions of order p >= 2, and
deterministic self-interactions u <= 0. We show that for nonzero u the effect
of increasing the order of the interactions is to make the system more
cooperative, in the sense that the fraction of extinct species is greatly
reduced. Furthermore, we find that for p > 2 there is a threshold value which
gives a lower bound to the concentration of the surviving species, preventing
then the existence of rare species and, consequently, increasing the robustness
of the ecosystem to external perturbations.

</DOC>
<DOC>
<DOCNO> 101819 </DOCNO>
Self-bumping of deformation spaces of hyperbolic 3-manifolds


  Let $N$ be a hyperbolic 3-manifold and $B$ a component of the interior of
$AH(\pi_1(N))$, the space of marked hyperbolic 3-manifolds homotopy equivalent
to $N$. We will give topological conditions on $N$ sufficient to give $\rho \in
\bar{B}$ such that for every small neighborhood $V$ of $\rho$, $V \cap B$ is
disconnected. This implies that $\bar{B}$ is not manifold with boundary.

</DOC>
<DOC>
<DOCNO> 102378 </DOCNO>
Generalised Brownian Motion and Second Quantisation


  A new approach to the generalised Brownian motion introduced by M. Bozejko
and R. Speicher is described, based on symmetry rather than deformation. The
symmetrisation principle is provided by Joyal's notions of tensorial and
combinatorial species. Any such species V gives rise to an endofunctor F_V of
the category of Hilbert spaces with contractions. A generalised Brownian motion
is an algebra of creation and annihilation operators acting on F_V(H) for
arbitrary Hilbert spaces H and having a prescription for the calculation of
vacuum expectations in terms of a function t on pair partitions. The positivity
is encoded by a *-semigroup of "broken pair partitions" whose representation
space with respect to t is V. The existence of the second quantisation as
functor Gamma_t from Hilbert spaces to noncommutative probability spaces is
proved to be equivalent to the multiplicative property of the function t. For a
certain one parameter interpolation between the fermionic and the free Brownian
motion it is shown that the ``field algebras'' Gamma(K) are type II_1 factors
when K is infinite dimensional.

</DOC>
<DOC>
<DOCNO> 40311 </DOCNO>
ADC common noise correction and zero suppression in the PIBETA detector


  We describe a simple procedure for reducing ADC common noise in modular
detectors that does not require additional hardware. A method using detector
noise groups should work well for modular particle detectors such as segmented
electromagnetic calorimeters, plastic scintillator hodoscopes, cathode strip
wire chambers, segmented active targets, and the like. We demonstrate a
``second pedestal noise correction'' method by comparing representative ADC
pedestal spectra for various elements of the PIBETA detector before and after
the applied correction.

</DOC>
<DOC>
<DOCNO> 8797 </DOCNO>
Comment on "Phase Diagram of the Random Energy Model with Higher-Order


  In a recent Physics Review Letter, Dorlas and Wedagedera have studied the
random energy model with an additional p-spin ferromagnetic interaction. Here
we note that (i) we have solved the corresponding problem of a spherical spin
system with p-spin glass interactions and r-spin ferromagnetic interactions,
and (ii) a simple mapping yields the results of DW and generalizations.
  Reference: http://arXiv.org/abs/cond-mat/9912201

</DOC>
<DOC>
<DOCNO> 151771 </DOCNO>
A New Expansion of the Heisenberg Equation of Motion with Projection


  We derive a new expansion of the Heisenberg equation of motion based on the
projection operator method proposed by Shibata, Hashitsume and Shing\=u. In
their projection operator method, a certain restriction is imposed on the
initial state. As a result, one cannot prepare arbitrary initial states, for
example a coherent state, to calculate the time development of quantum systems.
In this paper, we generalize the projection operator method by relaxing this
restriction. We explain our method in the case of a Hamiltonian both with and
without explicit time dependence. Furthermore, we apply it to an exactly
solvable model called the damped harmonic oscillator model and confirm the
validity of our method.

</DOC>
<DOC>
<DOCNO> 8767 </DOCNO>
Double-Layer Systems at Zero Magnetic Field


  We investigate theoretically the effects of intralayer and interlayer
exchange in biased double-layer electron and hole systems, in the absence of a
magnetic field. We use a variational Hartree-Fock-like approximation to analyze
the effects of layer separation, layer density, tunneling, and applied gate
voltages on the layer densities and on interlayer phase coherence. In agreement
with earlier work, we find that for very small layer separations and low layer
densities, an interlayer-correlated ground state possessing spontaneous
interlayer coherence (SILC) is obtained, even in the absence of interlayer
tunneling. In contrast to earlier work, we find that as a function of total
density, there exist four, rather than three, distinct noncrystalline phases
for balanced double-layer systems without interlayer tunneling. The newly
identified phase exists for a narrow range of densities and has three
components and slightly unequal layer densities, with one layer being spin
polarized, and the other unpolarized. An additional two-component phase is also
possible in the presence of sufficiently strong bias or tunneling. The
lowest-density SILC phase is the fully spin- and pseudospin-polarized
``one-component'' phase discussed by Zheng {\it et al.} [Phys. Rev. B {\bf 55},
4506 (1997)]. We argue that this phase will produce a finite interlayer Coulomb
drag at zero temperature due to the SILC. We calculate the particle densities
in each layer as a function of the gate voltage and total particle density, and
find that interlayer exchange can reduce or prevent abrupt transfers of charge
between the two layers. We also calculate the effect of interlayer exchange on
the interlayer capacitance.

</DOC>
<DOC>
<DOCNO> 170017 </DOCNO>
On oscillatorlike Hamiltonians and squeezing


  Generalizing a recent proposal leading to one-parameter families of
Hamiltonians and to new sets of squeezed states, we construct larger classes of
physically admissible Hamiltonians permitting new developments in squeezing.
Coherence is also discussed.

</DOC>
<DOC>
<DOCNO> 11850 </DOCNO>
Semi-classical theory of magnetic quantum oscillations in a


  The semi-classical Lifshitz-Kosevich (LK) description of quantum oscillations
is extended to a multiband two-dimensional Fermi liquid with a constant number
of electrons. The amplitudes of novel oscillations with combination
frequencies, recently predicted and observed experimentally, are analytically
derived and compared with the single-band amplitudes. The combination
amplitudes decay with temperature exponentially faster than the standard
harmonics, and this provides a valuable tool for their experimental
identification.

</DOC>
<DOC>
<DOCNO> 68339 </DOCNO>
Vector field mediated models of dynamical light velocity


  A vector-tensor theory of gravity that was introduced in an earlier
publication is analyzed in detail and its consequences for early universe
cosmology are examined. The multiple light cone structure of the theory
generates different speeds of gravitational and matter wave fronts, and the
contraction of these light cones produces acausal, superluminary inflation that
can resolve the initial value problems of cosmology.

</DOC>
<DOC>
<DOCNO> 40387 </DOCNO>
Measuring the SUSY Breaking Scale at the LHC in the Slepton NLSP


  We report a study on the measurement of the SUSY breaking scale sqrt(F) in
the framework of gauge-mediated supersymmetry breaking (GMSB) models at the
LHC. The work is focused on the GMSB scenario where a stau is the
next-to-lightest SUSY particle (NLSP) and decays into a gravitino with lifetime
c*tau_NLSP in the range 0.5 m to 1 km. We study the identification of
long-lived sleptons using the momentum and time of flight measurements in the
muon chambers of the ATLAS experiment. A realistic evaluation of the
statistical and systematic uncertainties on the measurement of the slepton mass
and lifetime is performed, based on a detailed simulation of the detector
response. Accessible range and precision on sqrt(F) achievable with a counting
method are assessed. Many features of our analysis can be extended to the study
of different theoretical frameworks with similar signatures at the LHC.

</DOC>
<DOC>
<DOCNO> 150573 </DOCNO>
Duality and Weyl Symmetry of 7-brane Configurations


  Extending earlier results on the duality symmetries of three-brane probe
theories we define the duality subgroup of SL(2,Z) as the symmetry group of the
background 7-branes configurations. We establish that the action of Weyl
reflections is implemented on junctions by brane transpositions that amount to
exchanging branes that can be connected by open strings. This enables us to
characterize duality groups of brane configurations by a map to the symmetry
group of the Dynkin diagram. We compute the duality groups and their actions
for all localizable 7-brane configurations. Surprisingly, for the case of
affine configurations there are brane transpositions leaving them invariant but
acting nontrivially on the charges of junctions.

</DOC>
<DOC>
<DOCNO> 116803 </DOCNO>
One Hundred Years of Quantum Physics


  On the occasion of the 100th anniversary of the birth of the quantum idea,
the development, achievements, and promises of quantum mechanics are described.

</DOC>
<DOC>
<DOCNO> 39880 </DOCNO>
New QCD estimate of the kaon penguin matrix elements and


  Firstly, we use the recent ALEPH/OPAL data on the V-A spectral functions for
fixing the continuum threshold with which the first and second Weinberg sum
rules should be satisfied in the chiral limit. Then, we predict the values of
the low-energy constants m_{\pi^+}-m_{\pi^0}, {L}_{10}, and test the values of
the electroweak kaon penguin matrix elements <Q^{3/2}_{8,7}>_{2\pi} obtained
from DMO--like sum rules. Secondly, we use the data on the \tau-total hadronic
width R_{\tau,V/A} for extracting <Q_8^{3/2}_{2\pi}>, in the {MS}\bar scheme,
and propose some new sum rules for < Q_7^{3/2}>_{2\pi} in the chiral limit,
where the latter require more accurate data for the spectral functions near the
$\tau$-mass. Thirdly, we analyze the effects to the matrix element
<Q_6^{1/2}>_{2\pi}, of the S_2\equiv(\bar uu+\bar dd) component of the I=0
scalar meson, with its parameters fixed from QCD spectral sum rules. Our
results should stimulate a further attention on the r\^ole of the (expected
large) gluonium component of the I=0 scalar meson and of the associated
operator in the K--->\pi\pi amplitude. Finally, using our previous
determinations, we deduce, in the Standard Model (SM), the conservative upper
bound for the CP-violating ratio: \epsilon'/\epsilon < (22\pm 9) 10^{-4}, which
is in agreement with the present measurements.

</DOC>
<DOC>
<DOCNO> 178611 </DOCNO>
Bose-Einstein correlations in heavy-ion and electron-positron collisions


  We shortly review recent successes in applying Bose-Einstein interferometry
in heavy ion collisions and the proceed to some model calculations for
3-dimensional Bose-Einstein correlation functions in electron-positron
collisions at the Z0 pole.

</DOC>
<DOC>
<DOCNO> 68813 </DOCNO>
Quantum and Classical Gauge Symmetries in a Modified Quantization Scheme


  The use of the mass term as a gauge fixing term has been studied by
Zwanziger, Parrinello and Jona-Lasinio, which is related to the non-linear
gauge $A_{\mu}^{2}=\lambda$ of Dirac and Nambu in the large mass limit. We have
recently shown that this modified quantization scheme is in fact identical to
the conventional {\em local} Faddeev-Popov formula {\em without} taking the
large mass limit, if one takes into account the variation of the gauge field
along the entire gauge orbit and if the Gribov complications can be ignored.
This suggests that the classical massive vector theory, for example, is
interpreted in a more flexible manner either as a gauge invariant theory with a
gauge fixing term added, or as a conventional massive non-gauge theory. As for
massive gauge particles, the Higgs mechanics, where the mass term is gauge
invariant, has a more intrinsic meaning.
 It is suggested to extend the notion of quantum gauge symmetry (BRST symmetry)
not only to classical gauge theory but also to a wider class of theories whose
gauge symmetry is broken by some extra terms in the classical action. We
comment on the implications of this extended notion of quantum gauge symmetry.

</DOC>
<DOC>
<DOCNO> 102526 </DOCNO>
Lefschetz pencils and divisors in moduli space


  We study Lefschetz pencils on symplectic four-manifolds via the associated
spheres in the moduli spaces of curves, and in particular their intersections
with certain natural divisors. An invariant defined from such intersection
numbers can distinguish manifolds with torsion first Chern class. We prove that
pencils of large degree always give spheres which behave `homologically' like
rational curves; contrastingly, we give the first constructive example of a
symplectic non-holomorphic Lefschetz pencil. We also prove that only finitely
many values of signature or Euler characteristic are realised by manifolds
admitting Lefschetz pencils of genus two curves.

</DOC>
<DOC>
<DOCNO> 99453 </DOCNO>
Wavelet filters and infinite-dimensional unitary groups


  In this paper, we study wavelet filters and their dependence on two numbers,
the scale N and the genus g. We show that the wavelet filters, in the
quadrature mirror case, have a harmonic analysis which is based on
representations of the C^*-algebra O_N. A main tool in our analysis is the
infinite-dimensional group of all maps T -> U(N) (where U(N) is the group of
all unitary N-by-N matrices), and we study the extension problem from low-pass
filter to multiresolution filter using this group.

</DOC>
<DOC>
<DOCNO> 120430 </DOCNO>
On a Theoretical Interpretation of the Period Gap in Binary Millisecond


  We reexamine evolutionary channels for the formation of binary millisecond
pulsars in order to understand their observed orbital period distribution. The
available paths provide a natural division into systems characterized by long
orbital periods (> 60 d) and short orbital periods (< 30 d). Systems with
initial periods 1 - 2 d ultimately produce low mass He white dwarfs with short
orbital periods (< 1 d). For longer initial periods (> few days), early massive
Case B evolution produces CO white dwarfs with orbital periods < 20 d. Common
envelope evolution result in short period systems (P < 1 d) from unstable low
mass Case B evolution producing He white dwarfs, and from unstable Case C
evolution leading to CO white dwarfs. On the other hand, the long orbital
period group arises from stable low mass Case B evolution with initial periods
> few days producing low mass He white dwarfs and periods > 30 d, and from
stable Case C evolution producing CO white dwarfs. The lack of observed systems
between 23 and 56 days probably reflects the fact that for comparable initial
orbital periods (< few days) low mass Case B and early massive Case B evolution
lead to very discrepant final periods. We show in particular that the lower
limit (~ 23 d) cannot result from common-envelope evolution.

</DOC>
<DOC>
<DOCNO> 9490 </DOCNO>
Exact Calculation of the Spatio-temporal Correlations in the Takayasu


  We calculate exactly the two point mass-mass correlations in arbitrary
spatial dimensions in the aggregation model of Takayasu. In this model, masses
diffuse on a lattice, coalesce upon contact and adsorb unit mass from outside
at a constant rate. Our exact calculation of the variance of mass at a given
site proves explicitly, without making any assumption of scaling, that the
upper critical dimension of the model is 2. We also extend our method to
calculate the spatio-temporal correlations in a generalized class of models
with aggregation, fragmentation and injection which include, in particular, the
$q$-model of force fluctuations in bead packs. We present explicit expressions
for the spatio-temporal force-force correlation function in the $q$-model.
These can be used to test the applicability of the $q$-model in experiments.

</DOC>
<DOC>
<DOCNO> 151279 </DOCNO>
Entropy and String Black Hole Correspondence


  We make some observations regarding string/black hole correspondence with a
view to understanding the nature of the quantum degrees of freedom of a black
hole in string theory. In particular, we compare entropy change in analogous
string and black hole processes in order to support the interpretation of the
area law entropy as arising from stringy constituents.

</DOC>
<DOC>
<DOCNO> 69236 </DOCNO>
Electromagnetic radiation of baryons containing two heavy quarks


  The two heavy quarks in a baryon which contains two heavy quarks and a light
one, can constitute a scalar or axial vector diquark. We study electromagnetic
radiations of such baryons, (i) \Xi_{(bc)_1} -> \Xi_{(bc)_0}+\gamma, (ii)
\Xi_{(bc)_1}^* -> \Xi_{(bc)_0}+\gamma, (iii) \Xi_{(bc)_0}^{**}(1/2, l=1) ->
\Xi_{(bc)_0}+\gamma, (iv) \Xi_{(bc)_0}^{**}(3/2, l=1) -> \Xi_{(bc)_0}+\gamma
and (v) \Xi_{(bc)_0}^{**}(3/2, l=2) -> \Xi_{(bc)_0}+\gamma, where
\Xi_{(bc)_{0(1)}}, \Xi^*_{(bc)_1} are S-wave bound states of a heavy scalar or
axial vector diquark and a light quark, and \Xi_{(bc)_0}^{**}(l is bigger than
1) are P- or D-wave bound states of a heavy scalar diquark and a light quark.
Analysis indicates that these processes can be attributed into two categories
and the physical mechanisms which are responsible for them are completely
distinct. Measurements can provide a good judgment for the diquark structure
and better understanding of the physical picture.

</DOC>
<DOC>
<DOCNO> 116257 </DOCNO>
Statistical mechanics of neocortical interactions: Canonical momenta


  A series of papers has developed a statistical mechanics of neocortical
interactions (SMNI), deriving aggregate behavior of experimentally observed
columns of neurons from statistical electrical-chemical properties of synaptic
interactions. While not useful to yield insights at the single neuron level,
SMNI has demonstrated its capability in describing large-scale properties of
short-term memory and electroencephalographic (EEG) systematics. The necessity
of including nonlinear and stochastic structures in this development has been
stressed. Sets of EEG and evoked potential data were fit, collected to
investigate genetic predispositions to alcoholism and to extract brain
signatures of short-term memory. Adaptive Simulated Annealing (ASA), a global
optimization algorithm, was used to perform maximum likelihood fits of
Lagrangians defined by path integrals of multivariate conditional
probabilities. Canonical momenta indicators (CMI) are thereby derived for
individual's EEG data. The CMI give better signal recognition than the raw
data, and can be used to advantage as correlates of behavioral states. These
results give strong quantitative support for an accurate intuitive picture,
portraying neocortical interactions as having common algebraic or physics
mechanisms that scale across quite disparate spatial scales and functional or
behavioral phenomena, i.e., describing interactions among neurons, columns of
neurons, and regional masses of neurons.

</DOC>
<DOC>
<DOCNO> 120154 </DOCNO>
Probing the gravitational well: No supernova explosion in spherical


  We report on the stellar core collapse, bounce, and postbounce evolution of a
13 solar mass star in a self-consistent general relativistic spherically
symmetric simulation based on Boltzmann neutrino transport. We conclude that
approximations to exact neutrino transport and omission of general relativistic
effects were not alone responsible for the failure of numerous preceding
attempts to model supernova explosions in spherical symmetry. Compared to
simulations in Newtonian gravity, the general relativistic simulation results
in a smaller shock radius. We however argue that the higher neutrino
luminosities and rms energies in the general relativistic case could lead to a
larger supernova explosion energy.

</DOC>
<DOC>
<DOCNO> 101237 </DOCNO>
Binary Representations of ABCD Matrices


  The ABCD matrix is one of the essential mathematical instruments in optics.
It is the two-by-two representation of the group Sp(2), which is applicable to
many branches of physics, including squeezed states of light, special
relativity and coupled oscillators. It is pointed out that the shear
representation is oriented to binary logic which may be friendly to computer
applications. While this is a future possibility, it is known that para-axial
lens optics is based on the shear representation of the Sp(2) group. It is
pointed out that the most general form of the ABCD matrix can be written in
terms of six shear matrices, which correspond to lens and translation matrices.
The parameter for each shear matrix is computed in terms of the three
independent parameters of the ABCD matrix.

</DOC>
<DOC>
<DOCNO> 11275 </DOCNO>
Replica symmetry breaking in long-range glass models without quenched


  We discuss mean field theory of glasses without quenched disorder focusing on
the justification of the replica approach to thermodynamics. We emphasize the
assumptions implicit in this method and discuss how they can be verified. The
formalism is applied to the long range Ising model with orthogonal coupling
matrix. We find the one step replica-symmetry breaking solution and show that
it is stable in the intermediate temperature range that includes the glass
state but excludes very low temperatures. At very low temperatures this
solution becomes unstable and this approach fails.

</DOC>
<DOC>
<DOCNO> 120546 </DOCNO>
The Evolved Red Stellar Content of M32


  Near-infrared images obtained with the CFHT AOB are used to investigate the
stellar content of the Local Group elliptical galaxy M32. Observations of a
field 2.3 arcmin from the galaxy center reveal a large population of AGB stars,
and comparisons with models indicate that these objects have an age log(t_Gyr)
< 9.3. It is concluded that intermediate age stars account for roughly 25% of
the total K light and 10% +/- 5% of the mass in this field.
  The K LF of bright sources between 20 and 30 arcsec from the nucleus is well
matched by the LF of the outer regions of the galaxy after accounting for
differences in surface brightness and correcting for crowding. It is concluded
that the relative size of the intermediate age component with respect to other
populations does not change with radius over most of the galaxy. However, the
integrated J-K color and 2.3 micron CO index change with radius within a few
tenths of an arcsec of the galaxy center indicating that, contrary to what
might be inferred from observations at visible wavelengths, the integrated
photometric properties of the central regions of M32 differ from those of the
surrounding galaxy.

</DOC>
<DOC>
<DOCNO> 150511 </DOCNO>
Dilatonic Randall-Sundrum Theory and renormalisation group


  We extend Randall-Sundrum dynamics to non-conformal metrics corresponding to
non-constant dilaton. We study the appareance of space-time naked singularities
and the renormalization group evolution of four-dimensional Newton constant.

</DOC>
<DOC>
<DOCNO> 84274 </DOCNO>
Current-Carrying Cosmic Strings in Scalar-Tensor Gravities


  We study the modifications on the metric of an isolated self-gravitating
bosonic superconducting cosmic string in a scalar-tensor gravity in the
weak-field approximation. These modifications are induced by an arbitrary
coupling of a massless scalar field to the usual tensorial field in the
gravitational Lagrangian. The metric is derived by means of a matching at the
string radius with a most general static and cylindrically symmetric solution
of the Einstein-Maxwell-scalar field equations. We show that this metric
depends on five parameters which are related to the string's internal structure
and to the solution of the scalar field. We compare our results with those
obtained in the framework of General Relativity.

</DOC>
<DOC>
<DOCNO> 40038 </DOCNO>
Status of PEP-II and BaBar


  In this report, the status of the PEP-II machine and the BaBar detector are
presented. Performance will be presented as of the Lepton Photon Conference
(August 1999) with subsequent performance levels footnoted as appropriate.

</DOC>
<DOC>
<DOCNO> 120513 </DOCNO>
Properties of PACE-I HgCdTe Detectors in Space - the NICMOS Warm-up


  We summarize the results of a monitoring program which was executed following
the cryogen exhaustion of the Near Infrared Camera and Multi-Object
Spectrometer (NICMOS) onboard the Hubble Space Telescope. During the subsequent
warm-up, detector parameters such as detective quantum efficiency, dark
current, bias offsets, and saturation levels have been measured over the
temperature range 62K to about 100K. The measurements provide a unique database
of the characteristics of PACE-I HgCdTe detector arrays in the space
environment. A surprising result of the analysis is the fact that all three
NICMOS detectors showed an enhanced dark current in the temperature range
between 77K and 85K. However, a subsequent laboratory experiment designed to
replicate the on-orbit warm-up did not reproduce the anomaly, despite the fact
that it employed a flight-spare detector of the same pedigree. The mechanism
behind the on-orbit dark current anomaly is therefore believed to be unique to
the space environment. We discuss possible explanations for these unexpected
observational results, as well as their implications for future NICMOS
operations.

</DOC>
<DOC>
<DOCNO> 13417 </DOCNO>
Quantum critical point in a periodic Anderson model


  We investigate the symmetric Periodic Anderson Model (PAM) on a
three-dimensional cubic lattice with nearest-neighbor hopping and hybridization
matrix elements. Using Gutzwiller's variational method and the Hubbard-III
approximation (which corresponds to the exact solution of an appropriate
Falicov-Kimball model in infinite dimensions) we demonstrate the existence of a
quantum critical point at zero temperature. Below a critical value $V_c$ of the
hybridization (or above a critical interaction $U_c$) the system is an {\em
insulator} in Gutzwiller's and a {\em semi-metal} in Hubbard's approach,
whereas above $V_c$ (below $U_c$) it behaves like a metal in both
approximations. These predictions are compared with the density of states of
the $d$- and $f$-bands calculated from Quantum Monte Carlo and NRG
calculations. Our conclusion is that the half-filled symmetric PAM contains a
{\em metal-semimetal transition}, not a metal-insulator transition as has been
suggested previously.

</DOC>
<DOC>
<DOCNO> 116870 </DOCNO>
Energy focusing inside a dynamical cavity


  We study the exact classical solutions for a real scalar field inside a
cavity with a wall whose motion is self-consistently determined by the pressure
of the field itself. We find that, regardless of the system parameters, the
long-time solution always becomes nonadiabatic and the field's energy
concentrates into narrow peaks, which we explain by means of a simple
mechanical system. We point out implications for the quantized theory.

</DOC>
<DOC>
<DOCNO> 40537 </DOCNO>
QCD measurements in photon-photon collisions at LEP


  An overview of the latest results of the LEP collaborations on QCD
measurements in photon-photon collisions is presented, including measurements
of the total hadronic cross-section, the production of heavy quarks and dijets
and the structure functions of real and virtual photons.

</DOC>
<DOC>
<DOCNO> 71010 </DOCNO>
Epsilon'/Epsilon in the Chiral Limit using Large N_c


  The K to pi pi system is analyzed in the chiral limit and at NLO in 1/N_c.
The Delta I = 1/2 rule is reproduced and we obtain a large value for epsilon' /
epsilon.

</DOC>
<DOC>
<DOCNO> 70095 </DOCNO>
Schwinger's Propagator Is Only A Green's Function


  Schwinger used an analytic continuation of the effective action to correctly
compute the particle production rate per unit volume for QED in a uniform
electric field. However, if one simply evaluates the one loop expectation value
of the current operator using his propagator, the result is zero! We analyze
this curious fact from the context of a canonical formalism of operators and
states. The explanation turns out to be that Schwinger's propagator is not
actually the expectation value of the time-ordered product of field operators
in the presence of a time-independent state, although it is of course a Green's
function. We compute the true propagator in the presence of a state which is
empty at $x_+ = 0$ where $x_+ \equiv (x^0+x^3)/\sqrt{2}$ is the lightcone
evolution parameter. Our result can be generalized to electric fields which
depend arbitrarily on $x_+$.

</DOC>
<DOC>
<DOCNO> 178576 </DOCNO>
Isospin Dependence of Nucleon-Nucleon Elastic Cross Section


  The in-medium neutron-proton, proton-proton(neutron-neutron) scattering cross
sections($\sigma_{np}^{*}$, $\sigma_{pp(nn)}^{*}$) are studied based on QHD-II
type Lagrangian within the framework of the microscopic transport theory. The
results demonstrate that, for free nucleon-nucleon scattering cross sections,
the isospin dependence is dominantly caused by $\rho$ meson field. The medium
correction of nucleon-nucleon scattering cross sections is also isospin
dependent, $\sigma_{np}^{*}$ depends on the baryon density weakly and
$\sigma_{pp(nn)}^{*}$ depends on the baryon density significantly, which is due
to the different effects of the medium correction of nucleon mass and $\rho$
meson mass on $\sigma_{np}$ and $\sigma_{pp(nn)}$, respectively

</DOC>
<DOC>
<DOCNO> 102372 </DOCNO>
Ternary algebraic structures and their applications in physics


  We discuss certain ternary algebraic structures appearing more or less
naturally in various domains of theoretical and mathematical physics. Far from
being exhaustive, this article is intended above all to draw attention to these
algebras, which may find more interesting applications in the years to come.

</DOC>
<DOC>
<DOCNO> 117611 </DOCNO>
Direct Distance Measurements to Superluminal Radio Sources


  We present a new technique for directly measuring the distances to
superluminal radio sources. By comparing the observed proper motions of
components in a parsec scale radio jet to their measured Doppler factors, we
can deduce the distance to the radio source independent of the standard rungs
in the cosmological distance ladder. This technique requires that the jet angle
to the line of sight and the ratio of pattern to flow velocities are
sufficiently constrained. We evaluate a number of possibilities for
constraining these parameters and demonstrate the technique on a well defined
component in the parsec scale jet of the quasar 3C279 (z = 0.536). We find an
angular size distance to 3C279 of greater than 1.8 (+0.5,-0.3) n^{1/8} Gpc,
where n is the ratio of the energy density in the magnetic field to the energy
density in the radiating particles in that jet component. For an Einstein-de
Sitter Universe, this measurement would constrain the Hubble constant to be H <
65 n^{-1/8} km/s/Mpc at the two sigma level. Similar measurements on higher
redshift sources may help discriminate between cosmological models.

</DOC>
<DOC>
<DOCNO> 100867 </DOCNO>
Poisson-Lie structures on Galilei group


  The complete list of Poisson-Lie structures on 4-d Galilei group is
presented.

</DOC>
<DOC>
<DOCNO> 123121 </DOCNO>
Observational Matter Power Spectrum and the Height of the Second


  We show that the amplitude of the second acoustic peak in the newly released
BOOMERANG-98 and MAXIMA-I data is compatible with the standard primordial
nucleosynthesis and with the locally broken-scale-invariant matter power
spectrum suggested by recent measurements of the power spectrum in the range
$20 - 200$ Mpc. If the slope of matter density perturbations on large scales is
$n \approx 1$, the Hubble constant is $0.5< h < 0.75$, and r.m.s. mass
fluctuations at 8 Mpc are $0.65 \le \sigma_8 \le 0.75$, then for a Universe
approximately 14 Gyr old our best fit within the nucleosynthesis bound
$\Omega_Bh^2= 0.019 \pm 0.0024$ requires $0.3 \le \Omega_m \le 0.5$. Cluster
abundances further constraint the matter density to be $\Omega_m \approx 0.3$.
The CMB data alone are not able to determine the detailed form of the matter
power spectrum in the range $0.03<k<0.06$ \hmpc where deviations from the
scale-invariant spectrum are expected to be most significant, but they do not
contradict the existence of the previously claimed peak at $k\sim 0.05$ \hmpc,
and a depression at $k\sim 0.035$ \hmpc.

</DOC>
<DOC>
<DOCNO> 10213 </DOCNO>
Scaling behavior for finite O(n) systems with long-range interaction


  A detailed investigation of the scaling properties of the fully finite ${\cal
O}(n)$ systems with long-range interaction, decaying algebraically with the
interparticle distance $r$ like $r^{-d-\sigma}$, below their upper critical
dimension is presented. The computation of the scaling functions is done to one
loop order in the non-zero modes. The results are obtained in an expansion of
powers of $\sqrt\epsilon$, where $\epsilon=2\sigma-d$ up to ${\cal
O}(\epsilon^{3/2})$. The thermodynamic functions are found to be functions the
scaling variable $z=RL^{2-\eta-\epsilon/2}U^{-1/2}$, where $R$ and $U$ are the
coupling constants of the constructed effective theory, and $L$ is the linear
size of the system. Some simple universal results are obtained.

</DOC>
<DOC>
<DOCNO> 13560 </DOCNO>
Impurity Site NMR Relaxation in Unconventional Superconductors


  Impurity nuclear spin relaxation is studied theoretically. A single impurity
generates a bound state localized around the impurity atom in unconventional
superconductors. With increasing impurity potential, the relaxation rate
$T_1^{-1}$ is reduced by the impurity potential. However, it has a peak at low
temperatures due to the impurity bound state. The peak disappears at
non-impurity sites. The impurity site NMR measurement detecting a local
electronic structure just on the impurity atom is very useful for identifying
the unconventional pairing states.

</DOC>
<DOC>
<DOCNO> 71622 </DOCNO>
A generating function for all-orders skyrmions


  We find the generating functions for the Lagrangians of all-orders summable
SU(2) Skyrmions. We then proceed to construct the explicit form of the
Lagrangian, order by order in the derivatives of the pion field for two classes
of models.

</DOC>
<DOC>
<DOCNO> 116524 </DOCNO>
Real time encoding of motion: Answerable questions and questionable


  In the past decade, a small corner of the fly's visual system has become an
important testing ground for ideas about coding and computation in the nervous
system. A number of results demonstrate that this system operates with a
precision and efficiency near the limits imposed by physics, and more generally
these results point to the reliability and efficiency of the strategies that
nature has selected for representing and processing visual signals. A recent
series of papers by Egelhaaf and coworkers, however, suggests that almost all
these conclusions are incorrect. In this contribution we place these
controversies in a larger context, emphasizing that the arguments are not just
about flies, but rather about how we should quantify the neural response to
complex, naturalistic inputs. As an example, Egelhaaf et al. (and many others)
compute certain correlation functions and use the apparent correlation times as
a measure of temporal precision in the neural response. This analysis neglects
the structure of the correlation function at short times, and we show how to
analyze this structure to reveal a temporal precision 30 times better than
suggested by the correlation time; this precision is confirmed by a much more
detailed information theoretic analysis. In reviewing other aspects of the
controversy, we find that the analysis methods used by Egelhaaf et al. suffer
from some mathematical inconsistencies, and that in some cases we are unable to
reproduce their experimental results. Finally, we present results from new
experiments that probe the neural response to inputs that approach more closely
the natural context for freely flying flies. These new experiments demonstrate
that the fly's visual system is even more precise and efficient under natural
conditions than had been inferred from our earlier work.

</DOC>
<DOC>
<DOCNO> 102729 </DOCNO>
Direct proof for the Scalar Product with Bethe eigenstate in Spin chains


  We present the simple and direct proof of the determinantal formula for the
scalar product of Bethe eigenstate with an arbitrary dual state. We briefly
review the direct calculation of the general scalar product with the help of
the factorizing operator and the construction of the factorizing operator
itself. We also comment on the previous determination of the scalar product of
Bethe eigenstate with an arbitrary dual state.

</DOC>
<DOC>
<DOCNO> 119946 </DOCNO>
The Stability of Disks in Cusped Potentials


  We confirm that a high rate of shear at the center is able to stabilize an
entire stellar disk against bar-forming (m=2) modes, irrespective of the dark
halo density. Our simulations of unstable power-law disks also yield the growth
rate and pattern speed of the dominant lop-sided (m=1) mode in close agreement
with that predicted by linear theory in our cleanest case. The one-armed modes,
which dominate models with extensive disks, can be controlled by tapering the
outer disk. Two-armed instabilities of hard-centered disks are more difficult
to identify because they are easily overwhelmed by particle noise.
Nevertheless, we have detected the predicted m=2 modes in simulations with very
large numbers of particles. Such bisymmetric instabilities in these disks are
provoked only by sharp edges and are therefore easily eliminated.
  We have constructed a cool disk model with an almost flat rotation curve and
a quasi-exponential density profile that is unambiguously stable. The halo in
this stable model has a large core radius, with the disk and bulge providing
almost all the rotational support in the inner parts.

</DOC>
<DOC>
<DOCNO> 121972 </DOCNO>
Maximum-entropy reconstruction of gravitational lenses using shear


  We demonstrate that the maximum-entropy method for gravitational lens
reconstruction presented in Bridle et al. (1998) may be applied even when only
shear \emph{or} magnification information is present. We also demonstrate that
the method can easily handle irregularly shaped observing fields and, because
shear is a non-local function of the lensing mass, reconstructions that use
shear information can successfully bridge small gaps in observations. For our
simulations we use a mass density distribution that is realistic for a z=0.4
cluster of total mass around 10^15 h^-1 M_solar. Using HST-quality shear data
alone, covering the area of four WFPC2 observations, we detect 60 per cent of
the mass of the cluster within the area observed, despite the mass sheet
degeneracy. This is qualitatively because the shear provides information about
the variations in the mass distribution, and our prior includes a positivity
constraint. We investigate the effect of using various sizes of observing field
and find that 50 to 100 per cent of the cluster mass is detected, depending on
the observing strategy and cluster shape. Finally we demonstrate how this
method can cope with strong lensing regions of a mass distribution.

</DOC>
<DOC>
<DOCNO> 13063 </DOCNO>
Three-loop critical exponents, amplitude functions, and amplitude ratios


  We use variational perturbation theory to calculate various universal
amplitude ratios above and below T_c in minimally subtracted phi^4-theory with
N components in three dimensions. In order to best exhibit the method as a
powerful alternative to Borel resummation techniques, we consider only to two-
and three-loops expressions where our results are analytic expressions. For the
critical exponents, we also extend existing analytic expressions for two loops
to three loops.

</DOC>
<DOC>
<DOCNO> 68481 </DOCNO>
Current Issues for Inflation


  Brief review of some current topics, including gravitino creation and large
extra dimensions.

</DOC>
<DOC>
<DOCNO> 12170 </DOCNO>
Effects of disorder and magnetic field in frustrated magnets


  In this work a site diluted antiferromagntic Ising model in the FCC lattice
is studied by Monte Carlo simulation. At low temperatures, we find that as the
external field is increased the transition from the antiferromagnetic phase to
the superantiferromagnetic one occurs through an intermediate phase which is
not present in the undiluted system. This new phase ordering has three distinct
values for the sublattice magnetizations corresponding to one of the phases
found in a recent mean field calculation thus suggesting that in strongly
frustrated systems many novel spins ordering may arises as found
experimentally, for instance, in some pyrochlores.

</DOC>
<DOC>
<DOCNO> 150899 </DOCNO>
The k-folded sine-Gordon model in finite volume


  We consider the k-folded sine-Gordon model, obtained from the usual version
by identifying the scalar field after k periods of the cosine potential. We
examine (1) the ground state energy split, (2) the lowest lying multi-particle
state spectrum and (3) vacuum expectation values of local fields in finite
spatial volume, combining the Truncated Conformal Space Approach, the method of
the Destri-de Vega nonlinear integral equation (NLIE) and semiclassical
instanton calculations. We show that the predictions of all these different
methods are consistent with each other and in particular provide further
support for the NLIE method in the presence of a twist parameter. It turns out
that the model provides an optimal laboratory for examining instanton
contributions beyond the dilute instanton gas approximation. We also provide
evidence for the exact formula for the vacuum expectation values conjectured by
Lukyanov and Zamolodchikov.

</DOC>
<DOC>
<DOCNO> 100038 </DOCNO>
On binary relations without non-identical endomorphisms


  On every set A there is a rigid binary relation, i.e. such a relation R that
there is no homomorphism (A,R)->(A,R) except the identity (Vopenka et al.
[1965]). We state two conjectures which strengthen this theorem. We prove these
conjectures for some cardinalities.

</DOC>
<DOC>
<DOCNO> 116904 </DOCNO>
Operational Aspects of the High Current Upgrade at the Unilac


  With the new GSI High Current Injector, the beam pulse intensity will be
increased by more than two orders of magnitude. The high beam power and the
short stopping range at particle energies below 12 MeV/u can destroy
accelerator components even during a single beam pulse. Therefore, the
operation of the whole accelerator facility has required major changes in
hardware, software and operating strategy. A sophisticated beam diagnostic
system is indispensable for a safe operation. Preferably non-destructive
devices were installed. Destructive elements, e.g. beam stoppers, slits,
apertures, were improved in order to withstand the high beam power. Automatic
damage prevention was realised by beam loss monitors comparing and evaluating
very fast beam current transformer signals. Additionally, the component status
will be controlled permanently. For foil stripping at 11.4 MeV/u, a magnetic
beam sweeping system was installed Thereby, the hit area will be increased
during one 100 micro sec pulse. During operation, manual variation of
parameters has to be reduced. Set-up and automatic beam adjustment procedures
have to exclude uncontrolled beam loss. The versatility of the UNILAC is
enhanced by the possible three-beam operation on a pulse-to-pulse basis. Since
November 1999 the upgraded UNILAC is serving the experiments.

</DOC>
<DOC>
<DOCNO> 68947 </DOCNO>
Proton-Proton Fusion in Effective Field Theory


  The rate for the fusion process $p + p \ra d + e^+ + \nu_e$ is calculated
using non-relativistic effective field theory. Including the four-nucleon
derivative interaction, results are obtained in next-to-leading order in the
momentum expansion. This reproduces the effects of the effective range
parameter. Coulomb interactions between the incoming protons are included
non-perturbatively in a systematic way. The resulting fusion rate is
independent of specific models and wavefunctions for the interacting nucleons.
At this order in the effective Lagrangian there is an unknown counterterm which
limits the numerical accuracy of the calculated rate given by the squared
reduced matrix element $\Lambda^2(0) = 7.37$. Assuming the counterterm to have
a natural magnitude, we estimate the accuracy of this result to be 6\% - 8\%.
This is consistent with previous nuclear physics calculations based on
effective range theory and inclusion of axial two-body weak currents. The true
magnitude of the counterterm can be determined from a precise measurement of
the cross-section for low-energy neutrino scattering on deuterons.

</DOC>
<DOC>
<DOCNO> 68043 </DOCNO>
Weak decay of uniformly accelerated protons and related processes


  We investigate the weak interaction emission of spin-1/2 fermions from
accelerated currents. As particular applications, we analyze the decay of
uniformly accelerated protons and neutrons, and the neutrino-antineutrino
emission from uniformly accelerated electrons. The possible relevance of our
results to astrophysics is also discussed.

</DOC>
<DOC>
<DOCNO> 67944 </DOCNO>
Single spin asymmetries in inclusive high energy hadron-hadron collision


  It has been realized for quite a long time that single-spin experiments, in
which one of the colliding objects is transversely polarized, can be helpful in
studying the properties of strong interaction in general and in testing Quantum
Chromodynamics (QCD) in particular.
  Striking effects have been observed in the past few years which deviate
drastically from the expectation of the perturbative QCD parton model.
  These effects have received much attention.
  New experiments of the similar type are underway and/or planned.
  Different theoretical attempts have been made to understand these effects.
  In this review, the special role played by singly polarized high-energy
hadron-hadron collisions in High Energy Spin Physics is emphasized.
  Characteristics of the available data for inclusive hadron productions are
briefly summarized.
  Different theoretical approaches for such processes are reviewed with special
attention to a non-perturbative model which explicitly takes the orbital motion
of the valence quarks and hadronic surface effects into account.
  The connection between such asymmetries and hyperon polarization in
unpolarized reactions is discussed.
  An example of the possible application of such experimental results in other
processes is given.

</DOC>
<DOC>
<DOCNO> 14095 </DOCNO>
Comment on ''Implementation of the LDA+U method using the full-potential


  By this Comment we would like to point out that the authors of Ref. 1 have
ignored the orbital magnetism that makes the theory irrelevant to the real
systems like NiO.It causes that the calculated result for the magnetic moment
of NiO substantially disagrees with the experimental observation. PACS:
71.70.E, 75.10.D,

</DOC>
<DOC>
<DOCNO> 119889 </DOCNO>
Magnetic flares and the optical variability of the X-ray transient XTE


  The simultaneous presence of a strong quasi periodic oscillation of period of
about 10 seconds in the optical and X-ray lightcurves of the X-ray transient
XTE J1118+480 suggests that a significant fraction of the optical flux
originates from the inner part of the accretion flow, where most of the X-rays
are produced. We present a model of magnetic flares in an accretion disc corona
where thermal cyclo-synchrotron emission contributes significantly to the
optical emission, while the X-rays are produced by inverse Compton scattering
of the soft photons produced by dissipation in the underlying disc and by the
synchrotron process itself. Given the observational constraints, we estimate
the values for the coronal temperature, optical depth and magnetic field
intensity, as well as the accretion rate for the source. Within our model we
predict a correlation between optical and hard X-ray variability and an
anticorrelation between optical and soft X-rays. We also expect optical
variability on flaring timescales (about tens of milliseconds), with a power
density spectrum similar to the one observed in the X-ray band. Finally we use
both the available optical/EUV/X-ray spectral energy distribution and the low
frequency time variability to discuss limits on the inner radius of the
optically thick disc.

</DOC>
<DOC>
<DOCNO> 100646 </DOCNO>
Singular Bohr-Sommerfeld Rules for 2D Integrable Systems


  In this paper, we describe Bohr-Sommerfeld rules for semi-classical
completely integrable systems with 2 degrees of freedom with non degenerate
singularities (Morse-Bott singularities) under the assumption that the energy
level of the first Hamiltonian is non singular. The more singular case of {\it
focus-focus} singularities is studied in [Vu Ngoc San, CPAM 2000] and [Vu Ngoc
San, PhD 1998] The case of 1 degree of freedom has been studied in [Colin de
Verdiere-Parisse, CMP 1999] Our theory is applied to some famous examples: the
geodesics of the ellipsoid, the $1:2$-resonance, and Schroedinger operators on
the sphere $S^2$. A numerical test shows that the semiclassical Bohr-Sommerfeld
rules match very accurately the ``purely quantum'' computations.

</DOC>
<DOC>
<DOCNO> 122265 </DOCNO>
Infrared Emission from Interstellar Dust. I. Stochastic Heating of Small


  We present a method for calculating the infrared emission from a population
of dust grains heated by starlight, including very small grains for which
stochastic heating by starlight photons results in high temperature transients.
Because state-to-state transition rates are generally unavailable for complex
molecules, we consider model PAH, graphitic, and silicate grains with realistic
vibrational mode spectra and realistic radiative properties. The vibrational
density of states is used in a statistical-mechanical description of the
emission process. Unlike previous treatments, our approach fully incorporates
multiphoton heating effects, important for large grains or strong radiation
fields. We discuss how the "temperature" of the grain is related to its
vibrational energy. By comparing with an "exact" statistical calculation of the
emission process, we determine the conditions under which the "thermal" and the
"continuous cooling" approximations can be used to calculate the emission
spectrum.
  We present results for the infrared emission spectra of PAH grains of various
sizes heated by starlight. We show how the relative strengths of the 6.2, 7.7,
and 11.3um features depend on grain size, starlight spectrum and intensity, and
grain charging conditions. We show results for grains in the "cold neutral
medium", "warm ionized medium", and representative conditions in
photodissociation regions. Our model results are compared to observed ratios of
emission features for reflection nebulae and photodissociation regions, the
Milky Way, normal spiral galaxies, and starburst galaxies.

</DOC>
<DOC>
<DOCNO> 7983 </DOCNO>
Pressure Induced Quantum Critical Point and Non-Fermi-Liquid Behavior in


  The phase diagram of BaVS3 is studied under pressure using resistivity
measurements. The temperature of the metal to nonmagnetic Mott insulator
transition decreases under pressure, and vanishes at the quantum critical point
p_cr=20kbar. We find two kinds of anomalous conducting states. The
high-pressure metallic phase is a non-Fermi liquid described by Delta rho = T^n
where n=1.2-1.3 at 1K < T < 60K. At p<p_cr, the transition is preceded by a
wide precursor region with critically increasing resistivity which we ascribe
to the opening of a soft Coulomb gap.

</DOC>
<DOC>
<DOCNO> 174591 </DOCNO>
Production of Charged Pions, Kaons and Antikaons in Relativistic C+C and


  Production cross sections of charged pions, kaons and antikaons have been
measured in C+C and C+Au collisions at beam energies of 1.0 and 1.8 AGeV for
different polar emission angles. The kaon and antikaon energy spectra can be
described by Boltzmann distributions whereas the pion spectra exhibit an
additional enhancement at low energies. The pion multiplicity per participating
nucleon M(pi+)/A_part is a factor of about 3 smaller in C+Au than in C+C
collisions at 1.0 AGeV whereas it differs only little for the C and the Au
target at a beam energy of 1.8 AGeV. The K+ multiplicities per participating
nucleon M(K+)/A_part are independent of the target size at 1 AGeV and at 1.8
AGeV. The K- multiplicity per participating nucleon M(K-)/A_part is reduced by
a factor of about 2 in C+Au as compared to C+C collisions at 1.8 AGeV. This
effect might be caused by the absorption of antikaons in the heavy target
nucleus. Transport model calculations underestimate the K-/K+ ratio for C+C
collisions at 1.8 AGeV by a factor of about 4 if in-medium modifications of K
mesons are neglected.

</DOC>
<DOC>
<DOCNO> 152624 </DOCNO>
One-Dimensional String Theory with Vortices as Upside-Down Matrix


  We study matrix quantum mechanics at a finite temperature equivalent to one
dimensional compactified string theory with vortex (winding) excitations. It is
explicitly demonstrated that the states transforming under non-trivial U(N)
representations describe various configurations vortices and anti-vortices. For
example, for the adjoint representation the Feynman graphs (representing
discretized world-sheets) contain two faces with the boundaries wrapping around
the compactified target space which is equivalent to a vortex-anti-vortex pair.
A technique is developed to calculate partition functions in a given
representation for the standard matrix oscillator. It enables us to obtain the
partition function in the presence of a vortex-anti-vortex pair in the double
scaling limit using an analytical continuation to the upside-down oscillator.
The Berezinski-Kosterlitz-Thouless phase transition occurs in a similar way and
at the same temperature as in the flat 2D space. A possible generalization of
our technique to any dimension of the embedding space is discussed.

</DOC>
<DOC>
<DOCNO> 40100 </DOCNO>
New results on atmospheric neutrinos from Soudan 2


  Neutrino interactions recorded in a 5.1 fiducial kiloton-year exposure of the
Soudan-2 iron tracking calorimeter are analyzed for effects of neutrino
oscillations. Using contained single track and single shower events, we update
our measurement of the atmospheric nu_mu/nu_e ratio-of-ratios and find R = 0.68
\pm 0.11 \pm 0.06. Assuming this anomalously low R-value is the result of nu_mu
flavor disappearance via nu_mu to nu_tau oscillation, we select samples of
charged current events which offer good resolution, event-by-event, for L/Enu
reconstruction. Oscillation-weighted Monte Carlo events are fitted to these
data events using a chisq function summed over bins of log(L/E_nu). The region
allowed in the (sin^2 2\theta, \Delta m^2) plane at 90% CL is obtained using
the Feldman-Cousins procedure: 0.46 < sin^2 2\theta < 1.0 and 2.2x10^-4 <
\Delta m^2 < 2.2x10^-2 ev^2. A small but relatively energetic sample of
partially contained nu_mu events has also been isolated. Their distribution in
log(L/E_vis) relative to null oscillation Monte Carlo is compatible with nu_mu
to nu_tau oscillation scenarios within the parameter region allowed by our
contained events.

</DOC>
<DOC>
<DOCNO> 72279 </DOCNO>
Role of the nonperturbative input in QCD resummed Drell-Yan


  We analyze the role of the nonperturbative input in the Collins, Soper, and
Sterman (CSS)'s $b$-space QCD resummation formalism for Drell-Yan transverse
momentum ($Q_T$) distributions, and investigate the predictive power of the CSS
formalism. We find that the predictive power of the CSS formalism has a strong
dependence on the collision energy $\sqrt{S}$ in addition to its well-known
$Q^2$ dependence, and the $\sqrt{S}$ dependence improves the predictive power
at collider energies. We show that a reliable extrapolation from perturbatively
resummed $b$-space distributions to the nonperturbative large $b$ region is
necessary to ensure the correct $Q_T$ distributions. By adding power
corrections to the renormalization group equations in the CSS formalism, we
derive a new extrapolation formalism. We demonstrate that at collider energies,
the CSS resummation formalism plus our extrapolation has an excellent
predictive power for $W$ and $Z$ production at all transverse momenta $Q_T\le
Q$. We also show that the $b$-space resummed $Q_T$ distributions provide a good
description of Drell-Yan data at fixed target energies.

</DOC>
<DOC>
<DOCNO> 69389 </DOCNO>
First Estimations of Cosmological Parameters From BOOMERANG


  The anisotropy of the cosmic microwave background radiation contains
information about the contents and history of the universe. We report new
limits on cosmological parameters derived from the angular power spectrum
measured in the first Antarctic flight of the BOOMERANG experiment. Within the
framework of inflation-motivated adiabatic cold dark matter models, and using
only weakly restrictive prior probabilites on the age of the universe and the
Hubble expansion parameter $h$, we find that the curvature is consistent with
flat and that the primordial fluctuation spectrum is consistent with scale
invariant, in agreement with the basic inflation paradigm. We find that the
data prefer a baryon density $\Omega_b h^2$ above, though similar to, the
estimates from light element abundances and big bang nucleosynthesis. When
combined with large scale structure observations, the BOOMERANG data provide
clear detections of both dark matter and dark energy contributions to the total
energy density $\Omega_{\rm {tot}}$, independent of data from high redshift
supernovae.

</DOC>
<DOC>
<DOCNO> 102639 </DOCNO>
Output Feedback Invariants


  The paper is concerned with the problem of determining a complete set of
invariants for output feedback. Using tools from geometric invariant theory it
is shown that there exists a quasi-projective variety whose points parameterize
the output feedback orbits in a unique way. If the McMillan degree $n\geq mp$,
the product of number of inputs and number of outputs, then it is shown that in
the closure of every feedback orbit there is exactly one nondegenerate system.

</DOC>
<DOC>
<DOCNO> 119520 </DOCNO>
X-ray reprocessing in Narrow-Line Seyfert 1 Galaxies: Ton S180 and Ark


  We present the results of spectral analysis of the ASCA data for the
Narrow-Line Seyfert 1 galaxy (NLS1) Ton S180 and simultaneous ASCA and RXTE
data modelling for the NLS1 Ark 564. We model both the primary and reflected
continuum as well as the iron K alpha line, the energy of which depends on the
ionization state of the reprocessor. We show that the reprocessing matter is
mildly ionized, and we find the soft to hard luminosity ratio to be about 2.5.
The accretion rate approximately corresponds to the Eddington limit value.

</DOC>
<DOC>
<DOCNO> 8226 </DOCNO>
Rupture of multiple parallel molecular bonds under dynamic loading


  Biological adhesion often involves several pairs of specific receptor-ligand
molecules. Using rate equations, we study theoretically the rupture of such
multiple parallel bonds under dynamic loading assisted by thermal activation.
For a simple generic type of cooperativity, both the rupture time and force
exhibit several different scaling regimes. The dependence of the rupture force
on the number of bonds is predicted to be either linear, like a square root or
logarithmic.

</DOC>
<DOC>
<DOCNO> 67887 </DOCNO>
Muon-proton Colliders: Leptoquarks, Contact Interactions and Extra


  We discuss the physics potential of the $\mu p$ collider; especially,
leptoquarks, leptogluons, R-parity violating squarks, contact interactions, and
large extra dimensions. We calculate the sensitivity reach for these new
physics at $\mu p$ colliders of various energies and luminosities.

</DOC>
<DOC>
<DOCNO> 118105 </DOCNO>
The HST view of the FR I / FR II dichotomy


  In order to explore how the FR I / FR II dichotomy is related to the nuclear
properties of radio galaxies, we studied a complete sample of 26 nearby FR II
radio galaxies using Hubble Space Telescope (HST) images and compared them with
a sample of FR I previously analyzed. FR I nuclei lie in the radio-optical
luminosity plane along a tight linear correlation, which argues for a common
synchrotron origin. FR II show a more complex behavior, which is however
clearly related to their optical spectral classification.
  Broad line FR II radio galaxies (BLRG) are located overall well above the FR
I correlation, suggesting that a contribution from thermal (disc) emission is
present. Three narrow line (NLRG) and one weak line radio galaxy (WLRG), in
which no nuclear source is seen, can be interpreted as the obscured
counter-parts of BLRG, in agreement with the current unification schemes.
  Conversely, in 5 sources of the sample, all of them NLRG or WLRG, optical
cores are located on the same correlation defined by FR I and with similar
radio and optical luminosities. This suggests that, in analogy to FR I, the
emission is dominated by synchrotron radiation and represents the optical
counter-part of the non-thermal radio cores. Interestingly, all these galaxies
are located in clusters, an environment typical of FR I.
  These results imply that, at least at low redshifts, the FR II population is
not homogeneous. Furthermore, the traditional dichotomy between edge darkened
and brightened radio morphology is not univocally connected with the innermost
nuclear structure, as we find FR~II with FR I-like nuclei and this has
interesting bearings from the point of view of the AGN unified models.

</DOC>
<DOC>
<DOCNO> 99821 </DOCNO>
Choix des signes pour la formalite de M. Kontsevich


  The explicit realization of M. Kontsevich's formality on $R^d$ is the main
step of the proof of formality theorem on any manifold. We present here a
coherent choice of orientations and signs in order to write completely M.
Kontsevich's proof for $R^d$, including all the signs appearing in the
formality equation.

</DOC>
<DOC>
<DOCNO> 122856 </DOCNO>
Small-scale structure deduced from X- and gamma-ray timing measurements


  X-ray timing observations of neutron stars and black holes are among the few
available probes of ultrastrong magnetic fields, strong gravity, high
densities, and the propagation of thermonuclear burning. Here we review the
evidence for these effects revealed with data from the Rossi Explorer in the
last five years. We also discuss the exciting prospects for making the first
quantitative tests of strong-gravity general relativistic predictions with a
large-area X-ray timing mission.

</DOC>
<DOC>
<DOCNO> 12952 </DOCNO>
Does EELS haunt your photoemission measurements?


  It has been argued in a recent paper by R. Joynt (R. Joynt, Science 284, p
777 (1999)) that in the case of poorly conducting solids the photoemission
spectrum close to the Fermi Energy may be strongly influenced by extrinsic loss
processes similar to those occurring in High Resolution Electron Energy Loss
Spectroscopy (HR-EELS), thereby obscuring information concerning the density of
states or one electron Green's function sought for. In this paper we present a
number of arguments, both theoretical and experimental, that demonstrate that
energy loss processes occurring once the electron is outside the solid,
contribute only weakly to the spectrum and can in most cases be either
neglected or treated as a weak structureless background.

</DOC>
<DOC>
<DOCNO> 121705 </DOCNO>
Charge densities above pulsar polar caps


  The ability of the neutron star surface to supply all or only part of the
charges filling the pulsar magnetosphere is crucial for the physics prevailing
within it, with direct consequences for the possible formation of pair creation
regions. We evaluate the conditions for $e^-$ emission from pulsar surfaces for
a simple Goldreich-Julian geometry taking both thermal and field emission
processes into account. Using recently published estimates for the equation of
state at the neutron star's surface, we show, that for a large range of $T_{\rm
surf}, B$ and $P$, the liberated charges will fully screen the accelerating
B-parallel electric field ${\rm E_\|}$. For surface temperatures $T_{\rm
surf}<2\cdot 10^5 $K a balance between field emission of electrons and
shielding of the field will occur. Even in the overidealised case of $T_{\rm
surf}=0$ one can expect a prodigious supply of electrons which will weaken the
accelerating ${\rm E_\|}$. We calculated the motion of electrons along selected
polar field lines numerically for the low temperature, field emission scenario
yielding their Lorentz factors as well as the produced radiation densities.
Inverse Compton and later curvature losses are seen to balance the acceleration
by the residual electric fields. We found that the conditions for magnetic pair
production are not met anywhere along the field lines up to a height of 1500
pulsar radii. We did not {\it a priori} assume an "inner gap", and our
calculations did not indicate the formation of one under realistic physical
conditions without the introduction of further assumptions.

</DOC>
<DOC>
<DOCNO> 70169 </DOCNO>
The Angular Momentum and g_1^p Sum Rules for the Proton


  The gauge invariant operator formulation of the angular momentum sum rule
${1\over2} = J_q + J_g$ for the proton is presented and contrasted with the sum
rule for the first moment of the polarised structure function $g_1^p$. The
decoupling of the axial charge $a^0$ from the angular momentum sum rule is
highlighted and the possible QCD field-theoretic basis for an angular momentum
sum rule of the form ${1\over2} = {1\over2}\D q + \D g + L_q + L_g$ is
critically discussed.

</DOC>
<DOC>
<DOCNO> 11804 </DOCNO>
Coarsened Lattice Spatial Disorder in the Thermodynamic Limit


  In this Rapid Research Note the application of recently introduced [Physica A
277 (2000) 157] entropic measure S_Delta of spatial disorder for systems of
finite-sized objects is presented. In the thermodynamic limit the critical
behaviour of coarsened lattice model of random two-phase systems is illustrated
for certain grain size distributions (GSDs) and chosen parameters. Also the
changes of spatial disorder, quantified by S_Delta, between the limit GSDs
clearly show that the topological equivalence of the two phases is broken.

</DOC>
<DOC>
<DOCNO> 169887 </DOCNO>
Quantum Computer as an Inference Engine


  We propose a new family of quantum computing algorithms which generalize the
Deutsch-Jozsa, Simon and Shor ones. The goal of our algorithms is to estimate
conditional probability distributions. Such estimates are useful in
applications of Decision Theory and Artificial Intelligence, where inferences
are made based on uncertain knowledge. The family of algorithms that we propose
is based on a construction method that generalizes a Fredkin-Toffoli (FT)
construction method used in the field of classical reversible computing. FT
showed how, given any binary deterministic circuit, one can construct another
binary deterministic circuit which does the same calculations in a reversible
manner. We show how, given any classical stochastic network (classical Bayesian
net), one can construct a quantum network (quantum Bayesian net) which can
perform the same calculations as the classical one, but in a (piecewise)
reversible manner. Thus, we extend the FT construction method so that it can be
applied to any stochastic circuit, not just binary deterministic ones.

</DOC>
<DOC>
<DOCNO> 68585 </DOCNO>
New Physics Effects From B Meson Decays


  In this talk, we point out some of the present and future possible signatures
of physics beyond the Standard Model from B-meson decays, taking R-parity
conserving and violating supersymmetry as illustrative examples.

</DOC>
<DOC>
<DOCNO> 70869 </DOCNO>
Z penguins and rare B decays


  Rare B decays of the type $b \to s~\ell^+\ell^-(\nu\bar\nu)$ are analyzed in
a generic scenario where New Physics effects enter predominantly via $Z$
penguin contributions. We show that this possibility is both phenomenologically
allowed and well motivated on theoretical grounds. The important role played in
this context by the lepton forward-backward asymmetry in $B\to K^*\ell^+\ell^-$
is emphasized.

</DOC>
<DOC>
<DOCNO> 102786 </DOCNO>
Invitation to higher local fields, Part II, section 2: Adelic


  This work introduces adelic constructions of direct images of differentials
and symbols in the two-dimensional case in the relative situation. In
particular, reciprocity laws for relative residues of differentials and symbols
are stated and applied to a construction of the Gysin map for Chow groups.

</DOC>
<DOC>
<DOCNO> 70650 </DOCNO>
Color Current Induced by Gluon in Background Field Method of QCD


  By using the background field method of QCD in a path integral approach, we
derive the equation of motion for the classical chromofield and for the gluon
in a system containing the gluon and the classical chromofield simultaneously.
This inhomogeneous field equation contains a current term, which is the
expectation value of a composite operator including linear, square and cubic
terms of the gluon field. We also derive identities which the current should
obey from the gauge invariance. We calculate the current at the leading order
where the current induced by the gluon is opposite in sign to that induced by
the quark. This is just the feature of the non-Abelian gauge field theory which
has asymptotic freedom. Physically, the induced current can be treated as the
'displacement' current in the polarized vacuum, and its effect is equivalent to
redefining the field and the coupling constant.

</DOC>
<DOC>
<DOCNO> 116871 </DOCNO>
Annealing of radiation induced defects in silicon in a simplified


  The concentration of primary radiation induced defects has been previously
estimated considering both the explicit mechanisms of the primary interaction
between the incoming particle and the nuclei of the semiconductor lattice, and
the recoil energy partition between ionisation and displacements, in the frame
of the Lindhard theory. The primary displacement defects are vacancies and
interstitials, that are essentially unstable in silicon. They interact via
migration, recombination, annihilation or produce other defects. In the present
work, the time evolution of the concentration of defects induced by pions in
medium and high resistivity silicon for detectors is modelled, after
irradiation. In some approximations, the differential equations representing
the time evolution processes could be decoupled. The theoretical equations so
obtained are solved analytically in some particular cases, with one free
parameter, for a wide range of particle fluences and/or for a wide energy range
of the incident particles, for different temperatures; the corresponding
stationary solutions are also presented.

</DOC>
<DOC>
<DOCNO> 12425 </DOCNO>
Incipient nodal pairing in planar d-wave superconductors


  The possibility of a second pairing transition $d\to d+is$ ($d+id^\prime$) in
planar $d$-wave superconductors which occurs in the absence of external
magnetic field, magnetic impurities or boundaries is established in the
framework of the non-perturbative phenomenon of dynamical chiral symmetry
breaking in the system of $2+1$-dimensional Dirac-like nodal quasiparticles. We
determine the critical exponents and quasiparticle spectral functions that
characterize the corresponding quantum critical behavior and discuss some of
its potentially observable spectral and transport features.

</DOC>
<DOC>
<DOCNO> 11969 </DOCNO>
Intrinsic finite-size effects in the two-dimensional XY model with


  This study investigates in detail the finite-size scaling of the
two-dimensional irrationally frustrated XY model. By means of Monte Carlo
simulations with entropic sampling, we examine the size dependence of the
specific heat, and find remarkable deviation from the conventional finite-size
scaling theory, which reveals novel intrinsic finite-size effects. Relaxation
dynamics of the system is also considered, and correspondingly, finite-size
scaling of the relaxation time is examined, again giving evidence for the
intrinsic finite-size effects and suggesting a zero-temperature glass
transition.

</DOC>
<DOC>
<DOCNO> 68298 </DOCNO>
|V_ub| and |V_cb|, Charm Counting and Lifetime Differences in Inclusive


  Inclusive bottom hadron decays are analyzed based on the heavy quark
effective field theory (HQEFT). Special attentions in this paper are paid to
the b\to u transitions and nonspectator effects. As a consequence, the CKM
quark mixing matrix elements |V_ub| and |V_cb| are reliably extracted from the
inclusive semileptonic decays B\to X_u e \nu and B\to X_c e \nu. Various
observables, such as the semileptonic branch ratio B_SL, the lifetime
differences among B^-, B^0, B_s and \Lambda_b hadrons, the charm counting n_c,
are predicted and found to be consistent with the present experimental data.

</DOC>
<DOC>
<DOCNO> 13207 </DOCNO>
Lyapunov exponents and transport in the Zhang model of Self-Organized


  We discuss the role played by the Lyapunov exponents in the dynamics of
Zhang's model of Self-Organized Criticality. We show that a large part of the
spectrum (slowest modes) is associated with the energy transpor in the lattice.
In particular, we give bounds on the first negative Lyapunov exponent in terms
of the energy flux dissipated at the boundaries per unit of time. We then
establish an explicit formula for the transport modes that appear as diffusion
modes in a landscape where the metric is given by the density of active sites.
We use a finite size scaling ansatz for the Lyapunov spectrum and relate the
scaling exponent to the scaling of quantities like avalanche size, duration,
density of active sites, etc ...

</DOC>
<DOC>
<DOCNO> 69901 </DOCNO>
Lamb Shift of 3P and 4P states and the determination of $\alpha$


  The fine structure interval of P states in hydrogenlike systems can be
determined theoretically with high precision, because the energy levels of P
states are only slightly influenced by the structure of the nucleus. Therefore
a measurement of the fine structure may serve as an excellent test of QED in
bound systems or alternatively as a means of determining the fine structure
constant $\alpha$ with very high precision. In this paper an improved analytic
calculation of higher-order binding corrections to the one-loop self energy of
3P and 4P states in hydrogen-like systems with low nuclear charge number $Z$ is
presented. A comparison of the analytic results to the extrapolated numerical
data for high $Z$ ions serves as an independent test of the analytic
evaluation. New theoretical values for the Lamb shift of the P states and for
the fine structure splittings are given.

</DOC>
<DOC>
<DOCNO> 120573 </DOCNO>
HST/STIS observations of GRB000301C: CCD imaging and NUV MAMA


  We present HST/STIS observations of the optical counterpart (OT) of the
gamma-ray burster GRB 000301C obtained on 2000 March 6, five days after the
burst. CCD clear aperture imaging reveals a R ~ 21.50+/-0.15 source with no
apparent host galaxy. An 8000 s, 1150 < lambda/A < 3300 NUV-MAMA prism spectrum
shows a relatively flat continuum (in f_lambda) between 2800 and 3300 A, with a
mean flux 8.7 (+0.8,-1.6)+/- 2.6 10^(-18) ergs/s/cm^2/A, and a sharp break
centered at 2797+/-25 A. We interpret it as HI Lyman break at z = 2.067+/-0.025
indicating the presence of a cloud with a HI column density log(HI) > 18 on the
line-of-sight to the OT. This value is conservatively a lower limit to the GRB
redshift. However, the facts that large N(HI) system are usually considered as
progenitors of present day galaxies and that other OTs are found associated
with star forming galaxies strongly suggest that it is the GRB redshift. In any
case, this represents the largest direct redshift determination of a gamma-ray
burster to date. Our data are compatible with an OT spectrum represented by a
power-law with an intrinsic index \alpha = 1.2((f_nu \propto nu^-alpha) and no
extinction in the host galaxy or with alpha = 0.5 and extinction by a SMC-like
dust in the OT rest-frame with A_V = 0.15. The large N(HI) and the lack of
detected host is similar to the situation for damped Ly-alpha absorbers at z >
2.

</DOC>
<DOC>
<DOCNO> 123051 </DOCNO>
The Binary Origins of Hot Subdwarfs: New Radial Velocities


  Multiple radial velocity observations have been obtained for a large sample
of local field subdwarf B (sdB) stars over a period of two years. SdB stars
appear to fall into three distinct groups based on their kinematic and
spectroscopic properties. The sdB's in Group I have no detectable spectral
lines from a cool companion, and show only small or insignificant velocity
variations. They represent about 35% of all sdB stars, which defines the upper
limit for the total fraction of non-binary sdB's. Group II sdB's are
single-lined spectroscopic binaries, comprising about 45% of the sample. Their
spectra resemble those in the first group, but they have significant or large
velocity variations and probable orbital periods on the order of a day. The
third group contains the remaining 20% of sdB's, those showing additional
spectral lines from a cool (FGK) main sequence or subgiant companion. All Group
III sdB's have slowly varying or nearly constant velocities, indicating periods
of many months to several years. Group II sdB's are obvious post-common
envelope systems, in strong contrast to the wide binaries of Group III. Current
data are insufficient to rule out the possibility that some sdB's in Group I
might be analogs of Group III binaries, with undetectably faint companions. The
clear division into three groups with such disparate properties suggests very
different evolutionary histories even though the current physical states are
essentially indistinguishable.

</DOC>
<DOC>
<DOCNO> 72128 </DOCNO>
BFKL Physics in Jet Production at e+e- colliders


  Virtual photon scattering in $e^+e^-$ collisions can result in events with
the electron-positron pair at large rapidity separation with hadronic activity
in between. The BFKL equation resums large logarithms that dominate the cross
section for this process. We report here on a Monte Carlo method for solving
the BFKL equation that allows kinematic constraints to be taken into account
and show results for $e^+e^-$ collisions.

</DOC>
<DOC>
<DOCNO> 84104 </DOCNO>
Quiescent cosmological singularities


  The most detailed existing proposal for the structure of spacetime
singularities originates in the work of Belinskii, Khalatnikov and Lifshitz. We
show rigorously the correctness of this proposal in the case of analytic
solutions of the Einstein equations coupled to a scalar field or stiff fluid.
More specifically, we prove the existence of a family of spacetimes depending
on the same number of free functions as the general solution which have the
asymptotics suggested by the Belinskii-Khalatnikov-Lifshitz proposal near their
singularities. In these spacetimes a neighbourhood of the singularity can be
covered by a Gaussian coordinate system in which the singularity is
simultaneous and the evolution at different spatial points decouples.

</DOC>
<DOC>
<DOCNO> 7912 </DOCNO>
Alternative Technique for "Complex" Spectra Analysis


  . The choice of a suitable random matrix model of a complex system is very
sensitive to the nature of its complexity. The statistical spectral analysis of
various complex systems requires, therefore, a thorough probing of a wide range
of random matrix ensembles which is not an easy task. It is highly desirable,
if possible, to identify a common mathematcal structure among all the ensembles
and analyze it to gain information about the ensemble- properties. Our
successful search in this direction leads to Calogero Hamiltonian, a
one-dimensional quantum hamiltonian with inverse-square interaction, as the
common base. This is because both, the eigenvalues of the ensembles, and, a
general state of Calogero Hamiltonian, evolve in an analogous way for arbitrary
initial conditions. The varying nature of the complexity is reflected in the
different form of the evolution parameter in each case. A complete
investigation of Calogero Hamiltonian can then help us in the spectral analysis
of complex systems.

</DOC>
<DOC>
<DOCNO> 120554 </DOCNO>
Bulk Viscosity of Magnetized Neutron Star Matter


  We study the effect of magnetic field on the bulk viscosity of nuclear matter
in neutron stars. We employ the framework of relativistic mean field theory to
observe the dense nuclear matter in neutron stars. The effects are first
studied for the case when the magnetic field does not exceed the critical value
to confine the electrons to the lowest Landau levels. We then consider the case
of intense magnetic field to evaluate viscosity for the URCA processes and show
that the inequality $p_{F}(e)+p_{F}(p)\geq p_{F}(n)$ is no longer required to
be satisfied for the URCA processes to proceed.

</DOC>
<DOC>
<DOCNO> 119734 </DOCNO>
Generation of Cosmic Magnetic Fields at Recombination


  It is shown that the standard cosmological model predicts {\it ab initio}
generation of large-scale but very small-amplitude cosmic magnetic fields at
the epoch of recombination of the primeval plasma. Matter velocities dominated
by coherent flows on a scale $L\approx 50h^{-1}(1+z)^{-1}$ Mpc lead to a dipole
of radiation flux in the frame of the moving matter. Thomson scattering of the
radiation differentially accelerates the electrons and ions, creating
large-scale coherent electric currents and magnetic fields. This process is
analyzed using magnetohydrodynamic equations which include a modification of
Ohm's law describing the effect of Thomson drag on the electrons. The field
strength is estimated to be $B\simeq 10^{-20}$G.

</DOC>
<DOC>
<DOCNO> 102718 </DOCNO>
Reduction of the co-dimension of light-like isotropic sub-manifolds


  We give a sufficient condition for a lightlike isotropic submanifold $M$, of
dimension $n$, which is not totally geodesic in a semi-Riemannian manifold of
constant curvature $c$ and of dimension $n+p (n < p)$, to admit a reduction of
codimension. We show that this condition is a necessary and sufficient
condition on the first transversal space of $M$. There are basic and
non-trivial differences from the Riemannian case, as developed by Dajczer
\textit{et al} in (\cite{dajczer}), due to the degenerate metric on $M$. This
result extends in some sense,the one in \cite{keti} and \cite{dajczer} to
lightlike isotropic submanifolds.

</DOC>
<DOC>
<DOCNO> 121879 </DOCNO>
Two-point correlation functions on the light cone: testing theoretical


  We examine the light-cone effect on the two-point correlation functions using
numerical simulations for the first time. Specifically, we generate several
sets of dark matter particle distributions on the light-cone up to z=0.4 and
z=2 over the field-of-view of \pi degree^2 from cosmological N-body
simulations. Then we apply the selection function to the dark matter
distribution according to the galaxy and QSO luminosity functions. Finally we
compute the two-point correlation functions on the light-cone both in real and
in redshift spaces using the pair-count estimator and compare with the
theoretical predictions. We find that the previous theoretical modeling for
nonlinear gravitational evolution, linear and nonlinear redshift-distortion,
and the light-cone effect including the selection function is in good agreement
with our numerical results, and thus is an accurate and reliable description of
the clustering in the universe on the light-cone.

</DOC>
<DOC>
<DOCNO> 118753 </DOCNO>
Geometric phase in phasing of antenna arrays


  The response of a pair of differently polarized antennas is determined by
their polarization states AND a phase between them which has a geometric part
which becomes discontinuous at singular points in the parameter space. Such
phase singularities have been observed in optical polarization experiments
[R.Bhandari, Physics Reports 281 (1997) 1]. It is pointed out that such a phase
is implicit in an equation for the response derived in the sixties [Morris et
al Ap.J. 139 (1964) 551].
 When a source emitting partially polarized radiation is observed with a
correlation interferometer consisting of two antennas with different
polarizations, curiously, fringes can be made to vanish for an appropriate
choice of the polarization states, in general non orthogonal [V Radhakrishnan,
Current Science 67 (1994) 257]. The result follows by considering the
interference as a superposition of two patterns due to the two orthogonal
polarization components of the radiation, which have a phase difference of
magnitude \pi, a geometric phase.

</DOC>
<DOC>
<DOCNO> 11908 </DOCNO>
Microscopic Theory of Heterogeneity and Non-Exponential Relaxations in


  Recent experiments and computer simulations show that supercooled liquids
around the glass transition temperature are "dynamically heterogeneous" [1].
Such heterogeneity is expected from the random first order transition theory of
the glass transition. Using a microscopic approach based on this theory, we
derive a relation between the departure from Debye relaxation as characterized
by the $\beta$ value of a stretched exponential response function $\phi(t)
=e^{-(t/ \tau_{KWW})^{\beta}}$, and the fragility of the liquid. The $\beta$
value is also predicted to depend on temperature and to vanish as the ideal
glass transition is approached at the Kauzmann temperature.

</DOC>
<DOC>
<DOCNO> 178568 </DOCNO>
Goldberger-Treiman Relation and g_piNN from the Three Quark BS/Faddeev


  A systematic evaluation method of matrix elements of quantum one-body
operators between nucleon states in the three-quark
Bethe-Salpeter(3qBS)/Faddeev approach in the NJL model is reviewed. We do not
confine ourselves to a particular truncation scheme of the 3qBS kernel. One of
our main aims is to derive a general condition to be imposed on a given BS
kernel in order that the PCAC relation is satisfied correctly. We apply this
condition to some particular 3qBS kernels. We numerically calculate g_piNN in
the 3qBS/Faddeev approach to estimate the violation of the
Goldberger-Treiman/PCAC relation due to the UV-regularization scheme. We
finally consider the non-vanishing current quark mass effects on the
Goldberger-Treiman relation.

</DOC>
<DOC>
<DOCNO> 69127 </DOCNO>
Nonperturbative Renormalization and the QCD Vacuum


  We present a self consistent approach to Coulomb gauge Hamiltonian QCD which
allows one to relate single gluon spectral properties to the long range
behavior of the confining interaction. Nonperturbative renormalization is
discussed. The numerical results are in good agreement with phenomenological
and lattice forms of the static potential.

</DOC>
<DOC>
<DOCNO> 9461 </DOCNO>
Mobile Bipolarons in the Adiabatic Holstein-Hubbard Model in 1 and 2


  The bound states of two electrons in the adiabatic Holstein-Hubbard model are
studied numerically in one and two dimensions from the anticontinuous limit.
This model involves a competition between a local electron-phonon coupling
(with a classical lattice) which tends to form pairs of electrons and the
repulsive Hubbard interaction $U \geq 0$ which tends to break them.
  In 1D, the ground-state always consists in a pair of localized polarons in a
singlet state. They are located at the same site for U=0. Increasing U, there
is a first order transition at which the bipolaron becomes a spin singlet pair
of two polarons bounded by a magnetic interaction. The pinning mode of the
bipolaron soften in the vicinity of this transition leading to a higher
mobility of the bipolaron which is tested numerically.
  In 2D, and for any $U$, the electron-phonon coupling needs to be large enough
in order to form small polarons or bipolarons instead of extended electrons. We
calculate the phase diagram of the bipolaron involving first order transitions
lines with a triple point. A pair of polarons can form three types of
bipolarons: a) on a single site at small $U$, b) a spin singlet state on two
nearest neighbor sites for larger $U$ as in 1D and c) a new intermediate state
obtained as the resonant combination of four 2-sites singlet states sharing a
central site, called quadrisinglet.
  The breathing and pinning internal modes of bipolarons in 2D generally only
weakly soften and thus, they are practically not mobile. On the opposite, in
the vicinity of the triple point involving the quadrisinglet, both modes
exhibit a significant softening. However, it was not sufficient for allowing
the existence of a classical mobile bipolaron (at least in that model).

</DOC>
<DOC>
<DOCNO> 121868 </DOCNO>
Irregular Magnetic Fields in Interstellar Clouds and Variations in the


  The strengths of magnetic fields in interstellar gas clouds are obtained
through observations of the circular polarization of spectral line radiation.
Irregularities in this magnetic field may be present due to turbulence, waves
or perhaps other causes, and may play an essential role in the structure and
evolution of the gas clouds. To infer information about these irregularities
from the observational data, we develop statistical relationships between the
rms values of the irregular component of the magnetic field and spatial
variations in the circular polarization of the spectral line radiation. The
irregularities are characterized in analogy with descriptions of
turbulence---by a sum of Fourier waves having a power spectrum with a slope
similar to that of Kolmogorov turbulence. For comparison, we also perform
computations in which turbulent magnetic and velocity fields from
representative MHD simulations by others are utilized. Although the effects of
the variations about the mean value of the magnetic field along the path of a
ray tend to cancel, a significant residual effect in the polarization of the
emergent radiation remains for typical values of the relevant parameters. A map
of observed spectra of the 21 cm line toward Orion A is analyzed and the
results are compared with our calculations in order to infer the strength of
the irregular component of the magnetic field. The rms of the irregular
component is found to be comparable in magnitude to the mean magnetic field
within the cloud. Hence, the turbulent and Alfven velocities should also be
comparable.

</DOC>
<DOC>
<DOCNO> 116757 </DOCNO>
Method of laser-radiation guiding in plasma


  The diffraction broadening of the intense laser radiation restricts its
efficient use in many applications. Proposed in the present work is a method
for laser radiation guiding in a density channel formed in plasma by a
relativistic electron beam. The conditions and parameters of the relativistic
beam ensuring the guiding by means of the proposed method have been examined.

</DOC>
<DOC>
<DOCNO> 100731 </DOCNO>
Coherence in Substructural Categories


  It is proved that MacLane's coherence results for monoidal and symmetric
monoidal categories can be extended to some other categories with
multiplication; namely, to relevant, affine and cartesian categories. All
results are formulated in terms of natural transformations equipped with
``graphs'' (g-natural transformations), and corresponding morphism theorems are
given as consequences. Using these results, some basic relations between the
free categories of these classes are obtained.

</DOC>
<DOC>
<DOCNO> 71800 </DOCNO>
Diffraction 2000: New Scaling Laws in Shadow Dynamics


  New scaling structure for the shadow corrections in elastic scattering from
deuteron at high energies has been presented and discussed. It is shown that
this structure corresponds to the experimental data on
proton(antiproton)-deuteron total cross sections. The effect of weakening for
the inelastic screening at superhigh energies has been theoretically predicted.

</DOC>
<DOC>
<DOCNO> 8465 </DOCNO>
Vortex state in a doped Mott insulator


  We analyze the recent vortex core spectroscopy experiments in cuprate
superconductor and discuss what can be learned from them about the nature of
the ground state in these compounds. We argue that the data are inconsistent
with the assumption of a simple metallic ground state and exhibit
characteristics of a doped Mott insulator. A theory for a vortex core in such a
doped Mott insulator is developed based on the U(1) gauge field slave boson
model and is shown to exhibit properties qualitatively consistent with the
experimental data.

</DOC>
<DOC>
<DOCNO> 40161 </DOCNO>
Measurements of B --> D_s^{(*)+} D^{*(*)} Branching Fractions


  This article describes improved measurements by CLEO of the $B^0 \to D_s^+
D^{*-}$ and $B^0 \to D_s^{*+} D^{*-}$ branching fractions, and first evidence
for the decay $B^+ \to D_s^{(*)+} \bar{D}^{**0}$, where $\bar{D}^{**0}$
represents the sum of the $\bar{D}_1(2420)^0$, $\bar{D}_2^*(2460)^0$, and
$\bar{D}_1(j=1/2)^0$ L=1 charm meson states. Also reported is the first
measurement of the $D_s^{*+}$ polarization in the decay $B^0 \to D_s^{*+}
D^{*-}$. A partial reconstruction technique, employing only the fully
reconstructed $D_s^+$ and slow pion $\pi_s^-$ from the $D^{*-} \to \bar{D}^0
\pi^-_s$ decay, enhances sensitivity. The observed branching fractions are
${\mathcal B} (B^0 \to D_s^+ D^{*-}) =
  (1.10 \pm 0.18 \pm 0.10 \pm 0.28)%$, ${\mathcal B} (B^0 \to D_s^{*+} D^{*-})
=
  (1.82 \pm 0.37 \pm 0.24 \pm 0.46)%$, and ${\mathcal B} (B^+ \to D_s^{(*)+}
\bar{D}^{**0}) =
  (2.73 \pm 0.78 \pm 0.48 \pm 0.68)%$, where the first error is statistical,
the second systematic, and the third is due to the uncertainty in the $D_s^+
\to \phi \pi^+$ branching fraction. The measured $D_s^{*+}$ longitudinal
polarization, $\Gamma_L/\Gamma = (50.6 \pm 13.9 \pm 3.6)%$, is consistent with
the factorization prediction of 54%.

</DOC>
<DOC>
<DOCNO> 84584 </DOCNO>
Quasi-Local Conservation Equations in General Relativity


  A set of exact quasi-local conservation equations is derived from the
Einstein's equations using the first-order Kaluza-Klein formalism of general
relativity in the (2,2)-splitting of 4-dimensional spacetime. These equations
are interpreted as quasi-local energy, momentum, and angular momentum
conservation equations. In the asymptotic region of asymptotically flat
spacetimes, it is shown that the quasi-local energy and energy-flux integral
reduce to the Bondi energy and energy-flux, respectively. In spherically
symmetric spacetimes, the quasi-local energy becomes the Misner-Sharp energy.
Moreover, on the event horizon of a general dynamical black hole, the
quasi-local energy conservation equation coincides with the conservation
equation studied by Thorne {\it et al}. We discuss the remaining quasi-local
conservation equations briefly.

</DOC>
<DOC>
<DOCNO> 120418 </DOCNO>
Simulations of accretion flows crossing the last stable orbit


  We use three dimensional magnetohydrodynamic simulations, in a
pseudo-Newtonian potential, to study geometrically thin accretion disc flows
crossing the marginally stable circular orbit around black holes. We
concentrate on vertically unstratified and isothermal disk models, but also
consider a model that includes stratification. In all cases, we find that the
sonic point lies just inside the last stable orbit, with a modest increase in
the importance of magnetic field energy, relative to the thermal energy,
observed interior to this radius. The time-averaged gradient of the specific
angular momentum of the flow, (dl/dr), is close to zero within the marginally
stable orbit, despite the presence of large fluctuations and continuing
magnetic stress in the plunging region. The result that the specific angular
momentum is constant within the last stable orbit is in general agreement with
traditional disk models computed using a zero-torque boundary condition at the
last stable orbit.

</DOC>
<DOC>
<DOCNO> 117815 </DOCNO>
Influence of the Tachocline on Solar Evolution


  Recently helioseismic observations have revealed the presence of a shear
layer at the base of the convective zone related to the transition from
differential rotation in the convection zone to almost uniform rotation in the
radiative interior, the tachocline. At present, this layer extends only over a
few percent of the solar radius and no definitive explanations have been given
for this thiness. Following Spiegel and Zahn (1992, Astron. Astrophys.), who
invoke anisotropic turbulence to stop the spread of the tachocline deeper in
the radiative zone as the Sun evolves, we give some justifications for their
hypothesis by taking into account recent results on rotating shear instability
(Richard and Zahn 1999, Astron. Astrophys.). We study the impact of the
macroscopic motions present in this layer on the Sun's structure and evolution
by introducing a macroscopic diffusivity $D_T$ in updated solar models. We find
that a time dependent treatment of the tachocline significantly improves the
agreement between computed and observed surface chemical species, such as the
$^7$Li and modify the internal structure of the Sun (Brun, Turck-Chi\`eze and
Zahn, 1999, in Astrophys. J.).

</DOC>
<DOC>
<DOCNO> 69302 </DOCNO>
Two loop matching conditions on $\bar{\rm MS}$ parton densities


  We discuss how the operator product expansion (OPE) can be used to derive
asymptotic expressions for certain integrals. This yields operator matrix
elements (OME's) which determine the matching conditions for $\bar{\rm MS}$
parton densities across heavy flavour thresholds. Then we construct four and
five-flavour densities from a three-flavour set via the AP equation using LO
and NLO splitting functions.

</DOC>
<DOC>
<DOCNO> 151809 </DOCNO>
The exact renormalisation group equation and the perturbed unitary


  The exact renormalisation group equation is studied for a two-dimensional
theory with exponential interaction and a background charge at infinity. The
motivation for studying this interaction is the flow between unitary minimal
models perturbed by Phi_{(1,3)}, and their realisation in terms of a quantum
group restricted sine-Gordon model.

</DOC>
<DOC>
<DOCNO> 120527 </DOCNO>
Constraining (\Omega_m,\Omega_\lambda) from strong lensing


  The knowledge of the redshift of multiple images in cluster-lenses allows to
determine precisely the total projected mass within the Einstein radius. The
observation of various multiple images in a same cluster is opening new
possibilities to constrain the curvature of the universe. Indeed, although the
influence of $\Omega_m$ and $\Omega_\lambda$ on the images formation is of the
second order, observations of many multiple images at different redshifts
formed by a regular cluster-lens should allow to constrain very accurately the
mass distribution of the cluster and to start to be sensitive to the
cosmological parameters entering the diameter angular distances. We present,
analytical expressions and numerical simulations that allow us to compute the
expected error bars on the cosmological parameters provided an HST/WFPC2
resolution image and spectroscopic redshifts for the multiple images. Numerical
tests on simulated data confirm the rather small uncertainties we could obtain
this way for the two popular cosmological world models: $\Omega_m=0.3{\pm
0.24}$, $\Omega_\lambda=0.7{\pm 0.5}$ or $\Omega_m=1.{\pm 0.33}$,
$\Omega_\lambda=0.{\pm 1.2}$.

</DOC>
<DOC>
<DOCNO> 10231 </DOCNO>
Probability distribution of the free energy of a directed polymer in a


  We calculate exactly the first cumulants of the free energy of a directed
polymer in a random medium for the geometry of a cylinder. By using the fact
that the n-th moment <Z^n> of the partition function is given by the ground
state energy of a quantum problem of n interacting particles on a ring of
length L, we write an integral equation allowing to expand these moments in
powers of the strength of the disorder gamma or in powers of n. For n small and
n of order (L gamma)^(-1/2), the moments <Z^n> take a scaling form which allows
to describe all the fluctuations of order 1/L of the free energy per unit
length of the directed polymer. The distribution of these fluctuations is the
same as the one found recently in the asymmetric exclusion process, indicating
that it is characteristic of all the systems described by the
Kardar-Parisi-Zhang equation in 1+1 dimensions.

</DOC>
<DOC>
<DOCNO> 40584 </DOCNO>
Neutrino Oscillation Effects in Indirect Detection of Dark Matter


  If neutrino oscillation plays a role in explaining the atmospheric neutrino
deficit, then the same phenomenon would necessarily affect also the dark matter
indirect-detection signal which consists in a muon-neutrino flux produced by
neutralino annihilation in the Earth core. In this paper we investigate to
which extent the upgoing-muon signal originated by neutralinos captured inside
the Earth would be affected by the presence of nu_mu -> nu_tau oscillation.

</DOC>
<DOC>
<DOCNO> 117679 </DOCNO>
Thermal X-Ray Pulses Resulting From Pulsar Glitches


  The non-spherically symmetric transport equations and exact thermal evolution
model are used to calculate the transient thermal response to pulsars. The
three possible ways of energy release originated from glitches, namely the
`shell', `ring' and `spot' cases are compared. The X-ray light curves resulting
from the thermal response to the glitches are calculated. Only the `spot' case
and the `ring' case are considered because the `shell' case does not produce
significant modulative X-rays. The magnetic field ($\vec B$) effect, the
relativistic light bending effect and the rotational effect on the photons
being emitted in a finite region are considered. Various sets of parameters
result in different evolution patterns of light curves. We find that this
modulated thermal X-ray radiation resulting from glitches may provide some
useful constraints on glitch models.

</DOC>
<DOC>
<DOCNO> 101528 </DOCNO>
No-nonsense Casimir force


  Two thin conducting, electrically neutral, parallel plates forming an
isolated system in vacuum exert attracting force on each other, whose origin is
the quantum electrodynamical interaction. This theoretical hypothesis, known as
Casimir effect, has been also confirmed experimentally. Despite long history of
the subject, no completely convincing theoretical analysis of this effect
appears in the literature. Here we discuss the effect (for the scalar field)
anew, on a revised physical and mathematical basis. Standard, but advanced
methods of relativistic quantum theory are used. No anomalous features of the
conventional approaches appear. The Casimir quantitative prediction for the
force is shown to constitute the leading asymptotic term, for large separation
of the plates, of the full, model-dependent expression.

</DOC>
<DOC>
<DOCNO> 7900 </DOCNO>
Avalanches of popping bubbles in collapsing foams


  We report acoustic experiments on foam systems. We have recorded the sound
emitted by crackling cells during the collapsing of foams. The sound pattern is
then analyzed using classical methods of statistical physics. Fundamental
processes at the surface of the collapsing foam are found. In particular, size
is not a relevant parameter for exploding bubbles.

</DOC>
<DOC>
<DOCNO> 80873 </DOCNO>
Kaon B parameter from quenched domain-wall QCD


  We report on a calculation of $B_K$ with domain wall fermion action in
quenched QCD. Simulations are made with a renormalization group improved gauge
action at $\beta=2.6$ and 2.9 corresponding to $a^{-1}\approx 2$GeV and 3GeV.
Effects due to finite fifth dimensional size $N_5$ and finite spatial size
$N_\sigma$ are examined in detail. Matching to the continuum operator is made
perturbatively at one loop order. We obtain $B_K(\mu = 2 {GeV})= 0.5746(61)$,
where the error is statistical only, as an estimate of the continuum value in
the $\msbar$ scheme with naive dimensional regularization. This value is
smaller but consistent with $B_K(\mu = 2 {GeV})= 0.628(42)$ obtained by the
JLQCD Collaboration using the Kogut-Susskind quark action. Results for strange
quark mass are also reported.

</DOC>
<DOC>
<DOCNO> 7639 </DOCNO>
Extended d_{x^2 - y^2}-wave superconductivity


  Remarkable anisotropic structures have been recently observed in the order
parameter Delta_k of the underdoped superconductor Bi-2212. Such findings are
strongly suggestive of deviations from a simple d_{x^2 - y^2}-wave picture of
high-Tc superconductivity, i.e. Delta_k ~ cos (k_x) - cos (k_y). In particular,
flatter nodes in Delta_k are observed along the k_x = (+/-) k_y directions in
k-space, than within this simple model for a d-wave gap. We argue that
nonlinear corrections in the k-dependence of Delta_k near the nodes introduce
new energy scales, which would lead to deviations in the predicted power-law
asymptotic behaviour of several measurable quantities, at low or intermediate
temperatures. We evaluate such deviations, either analytically or numerically,
within the interlayer pair-tunneling model, and within yet another
phenomenological model for a d-wave order parameter. We find that such
deviations are expected to be of different sign in the two cases. Moreover, the
doping dependence of the flatness of the gap near the nodes is also
attributable to Fermi surface effects, in addition to possible screening
effects modifying the in-plane pairing kernel, as recently proposed.

</DOC>
<DOC>
<DOCNO> 102359 </DOCNO>
Hamilton Variational Principle for Statisticl Ensemble of Deterministic


  Hamilton variational principle for special type of statistical ensemble of
deterministic dynamical systems is derived. Thie form of variational principle
allows one to describe the statistical ensemble in terms of wave functions and
provides a basis for a description of statistical ensemble of stochastic
systems. It is shown that sometimes such a statistical description of
stochastic particle motion appears to coincide with the quantum description in
terms of Schroedinger equation.

</DOC>
<DOC>
<DOCNO> 150426 </DOCNO>
Higher Order Anomaly Consistency Conditions: Renormalization and


  We study the Slavnov-Taylor Identities (STI) breaking terms, up to the second
order in perturbation theory. We investigate which requirements are needed for
the first order Wess-Zumino consistency condition to hold true at the next
order in perturbation theory. We find that: a) If the cohomologically trivial
contributions to the first order ST breaking terms are not removed by a
suitable choice of the first order normalization conditions, the Wess-Zumino
consistency condition is modified at the second order. b) Moreover, if one
fails to recover the cohomologically trivial part of the first order STI
breaking local functional, the second order anomaly actually turns out to be a
non-local functional of the fields and the external sources. By using the
Wess-Zumino consistency condition and the Quantum Action Principle, we show
that the cohomological analysis of the first order STI breaking terms can
actually be performed also in a model (the massive Abelian Higgs-Kibble one)
where the BRST transformations are not nilpotent.

</DOC>
<DOC>
<DOCNO> 117497 </DOCNO>
X-rays and Cosmology


  The role of X-ray observations for cosmological studies and conclusions is
briefly explored. X-rays currently yield cosmologically interesting results on
the abundances, evolution and gas content of clusters of galaxies, on the
clustering and evolution of active galaxies and on the X-ray Background. They
are unlikely in the long term future to give the most precise values of the
cosmological parameters, although in the short term the baryon fraction of
clusters and the Sunyaev-Zeldovich effect will remain important determinants
and checks for some parameters. X-rays will however continue to play an
important role in studying the astrophysics of the formation and growth of
black holes, galaxies, groups and clusters. It is possible that this role will
be crucial, if winds from active galaxies are responsible for breaking the
simple gravitational scaling laws for clusters.

</DOC>
<DOC>
<DOCNO> 67688 </DOCNO>
Propagation of ultrahigh-energy neutrinos through the Earth


  The dispersion relation in matter of ultrahigh-energy neutrinos above the
pole of the $W$ resonance ($E_{\nu} \gsim {\rm 10}^{7} {\rm GeV} $), is
studied. We perform our calculation using the real-time formulation of Thermal
Field Theory in which the massless limit for the $W$ boson is taken. The range
of active-to-sterile neutrino oscillation parameters for which there is
significant mixing enhancement during propagation through the interior of the
Earth, and therefore significant attenuation of neutrino beams in the Earth at
high energies, is estimated. Finally, this range is considered in view of the
cosmological and astrophysical constraints.

</DOC>
<DOC>
<DOCNO> 69783 </DOCNO>
Perturbation Spectra in the Warm Inflationary Scenario


  We investigate the phenomenology of warm inflation and present generic
results about the evolution of the inflaton and radiation fields. The general
conditions required for warm inflation to take place are derived and discussed.
A comprehensive approach is presented for the generation of thermally induced
adiabatic and isocurvature perturbations and the amplitude of their spectra
calculated. In addition we derive the ratio of tensor-to-scalar perturbations
and find the spectral indices for adiabatic, isocurvature and tensor
perturbations formed in the warm inflationary era. These results are presented
in a simplified and compact approach that is generally applicable. Our results
are illustrated by inflation models with polynomial and exponential potentials.
We compare our analytic results against numerical models and find excellent
agreement. Finally, presently available data is used to put constraints on warm
inflation and we discuss how near--future observations may distinguish the warm
inflationary scenario from standard supercooled inflation. The main observable
difference is the different scalar-to- tensor ratio, and that the consistency
relation between this and the slope of tensor perturbations does not hold for
warm inflation.

</DOC>
<DOC>
<DOCNO> 12467 </DOCNO>
Exact Solution of Asymmetric Diffusion With N Classes of Particles of


  The exact solution of the asymmetric exclusion problem with N distinct
classes of particles (c = 1,2,...,N), with hierarchical order is presented.
  In this model the particles (size 1) are located at lattice points, and
diffuse with equal asymmetric rates, but particles in a class c do not
distinguish those in the classes c' >c from holes (empty sites). We generalize
and solve exactly this model by considering the molecules in each distinct
class c =1,2,...,N with sizes s_c (s_c = 0,1,2,...), in units of lattice
spacing. The solution is derived by a Bethe ansatz of nested type.

</DOC>
<DOC>
<DOCNO> 67797 </DOCNO>
Effects of Bose-Einstein Condensation on forces among bodies sitting in


  We explore the consequences of Bose-Einstein condensation on
two-scalar-exchange mediated forces among bodies that sit in a boson gas. We
find that below the condensation temperature the range of the forces becomes
infinite while it is finite at temperatures above condensation.

</DOC>
<DOC>
<DOCNO> 116744 </DOCNO>
Chapman's model for ozone concentration: earth`s slowing rotation effect


  Chapman's model for ozone concentration is studied. In this nonlinear model,
the photodissociation coefficients for $O_{2}$ and $O_{3}$ are time-depending
due to earth-rotation. From the Kapitsa's method, valid in the high frequency
limit, we find the criterion for the existence of equilibrium solutions. These
solutions are depending on the frequency, and require a rotation period $T$
which satisfies $T<T_{1}$ or $T>T_{2}$. Where the critical periods $T_{1}$ and
$T_{2}$, with $T_{2}>T_{1}$, are a function of the parameters of the system
(reaction rates and photodissociation coefficients). Conjectures respect to the
retardation of the earth's rotation, due to friction, suggest that the
criterion was not even verified in the atmospheric past.

</DOC>
<DOC>
<DOCNO> 70800 </DOCNO>
Top quark threshold production in $\gamma\gamma$ collisions: current


  The top quark-antiquark pair threshold production at future High Energy
Photon Colliders is considered in view of the recent advances in the
theoretical description of the nonrelativistic heavy quark dynamics.

</DOC>
<DOC>
<DOCNO> 67955 </DOCNO>
Impeding and Unimpeding Gamma: The Principle of Impedance


  We demonstrate that gamma (from the Lorentz transformation of the Special
Theory of Relativity) acts as an impediment to velocity changes only when it
occurs inside motion energy transfer relationships. We also examine whether or
not gamma unimpeded velocity changes violate either the constancy of light or
elementary causality. We find that no violations occur. We conclude the paper
with the procedure for a simple experiment, and further empirical evidence from
the Hubble Space Telescope and W.M. Keck Observatory, all of which help to
establish the veracity of our "principle of impedance."

</DOC>
<DOC>
<DOCNO> 101587 </DOCNO>
The natural metric in the Horrocks-Mumford bundle is not


  The Horrocks-Mumford bundle $E$ is a famous stable complex vector bundle of
rank 2 on 4-dimensional complex projective space. By construction, $E$ has a
natural Hermitian metric $h_1$. On the other hand, stability implies the
existence of a Hermitian-Einstein metric in $E$ which is unique up to a
positive scalar. Now the obvious question is if $h_1$ is in fact the
Hermitian-Einstein metric. In this note we indicate how to show by computation
that this is not the case.

</DOC>
<DOC>
<DOCNO> 71689 </DOCNO>
Charged particle rapidity distributions at RHIC


  Using a multiphase transport model (AMPT), which includes both initial
partonic and final hadronic interactions, we study the rapidity distributions
of charged particles such as protons, antiprotons, pions, and kaons in heavy
ion collisions at RHIC. The theoretical results for the total charged particle
multiplicity at midrapidity are consistent with those measured by the PHOBOS
collaboration in central Au+Au collisions at $\sqrt s$ = 56 and 130 AGeV. We
find that these hadronic observables are much more sensitive to the hadronic
interactions than the partonic interactions.

</DOC>
<DOC>
<DOCNO> 117983 </DOCNO>
Shellflow. I. The Convergence of the Velocity Field at 6000 km/s


  We present the first results from the Shellflow program, an all-sky
Tully-Fisher (TF) peculiar velocity survey of 276 Sb-Sc galaxies with redshifts
between 4500 and 7000 km/s. Shellflow was designed to minimize systematic
errors between observing runs and between telescopes, thereby removing the
possibility of a spurious bulk flow caused by data inhomogeneity. A fit to the
data yields a bulk flow amplitude V_bulk = 70{+100}{-70} km/s (1 sigma error)
with respect to the Cosmic Microwave Background, i.e., consistent with being at
rest. At the 95% confidence level, the flow amplitude is < 300 km/s. Our
results are insensitive to which Galactic extinction maps we use, and to the
parameterization of the TF relation. The larger bulk motion found in analyses
of the Mark III peculiar velocity catalog are thus likely to be due to
non-uniformities between the subsamples making up Mark III. The absence of bulk
flow is consistent with the study of Giovanelli and collaborators and flow
field predictions from the observed distribution of IRAS galaxies.

</DOC>
<DOC>
<DOCNO> 169642 </DOCNO>
On local invariants of pure three-qubit states


  We study invariants of three-qubit states under local unitary
transformations, i.e. functions on the space of entanglement types, which is
known to have dimension 6. We show that there is no set of six independent
polynomial invariants of degree less than or equal to 6, and find such a set
with maximum degree 8. We describe an intrinsic definition of a canonical state
on each orbit, and discuss the (non-polynomial) invariants associated with it.

</DOC>
<DOC>
<DOCNO> 70618 </DOCNO>
BOOMERanG Data Suggest a Purely Baryonic Universe


  The amplitudes of peaks in the angular power spectrum of anisotropies in the
microwave background radiation depend on the mass content of the universe. The
second peak should be prominent when cold dark matter is dominant, but is
depressed when baryons dominate. Recent microwave background data are
consistent with a purely baryonic universe with Omega(matter) = Omega(baryon) ~
0.03 and Omega(Lambda) ~ 1.

</DOC>
<DOC>
<DOCNO> 122157 </DOCNO>
Accurate masses of very low mass stars: III 16 new or improved masses


  We have obtained adaptive optics images and accurate radial velocities for 7
very low mass systems, in the course of a long term effort to determine
accurate masses for very low mass stars (M<0.6 Solar Mass). We use the new
data, together with measurements from the litterature for some stars, to
determine new or improved orbits for these 7 systems. They provide masses for
16 very low mass stars with accuracies that range between 0.2% and 5%, and in
some cases a very accurate distance as well. This information is used in a
companion paper to discuss the Mass-Luminosity relation for the V, J, H and K
photometric bands.

</DOC>
<DOC>
<DOCNO> 100246 </DOCNO>
Long-time tails in the parabolic Anderson model with bounded potential


  We consider the parabolic Anderson problem $\partial_t u=\kappa\Delta u+\xi
u$ on $(0,\infty)\times \Z^d$ with random i.i.d. potential
$\xi=(\xi(z))_{z\in\Z^d}$ and the initial condition $u(0,\cdot)\equiv1$. Our
main assumption is that $\esssup\xi(0)=0$. Depending on the thickness of the
distribution $\prob(\xi(0)\in\cdot)$ close to its essential supremum, we
identify both the asymptotics of the moments of $u(t,0)$ and the almost-sure
asymptotics of $u(t,0)$ as $t\to\infty$ in terms of variational problems. As a
by-product, we establish Lifshitz tails for the random Schr\"odinger operator
$-\kappa\Delta-\xi$ at the bottom of its spectrum. In our class of $\xi$
distributions, the Lifshitz exponent ranges from $d/2$ to $\infty$; the power
law is typically accompanied by lower-order corrections.

</DOC>
<DOC>
<DOCNO> 118408 </DOCNO>
Detection of CO in the inner part of M31's bulge


  We report the first detection of CO in M31's bulge. The 12CO (1-0) and (2-1)
lines are both detected in the dust complex D395A/393/384, at 1.3" (~0.35 kpc)
from the centre. From these data and from visual extinction data, we derive a
CO-luminosity to reddening ratio (and a CO-luminosity to H_2 column density
ratio) quite similar to that observed in the local Galactic clouds. The (2-1)
to (1-0) line intensity ratio points to a CO rotational temperature and a gas
kinetic temperature > 10 K. The molecular mass of the complex, inside a 25'
(100 pc) region, is 1.5 10^4 Mo.

</DOC>
<DOC>
<DOCNO> 101971 </DOCNO>
Mixed Non-Euclidean Geometries


  The goal of this paper is to experiment new math concepts and theories,
especially if they run counter to the classical ones. To prove that
contradiction is not a catastrophe, and to learn to handle it in an (un)usual
way. To transform the apparently unscientific ideas into scientific ones, and
to develop their study (The Theory of Imperfections). And finally, to
interconnect opposite (and not only) human fields of knowledge into
as-heterogeneous-as-possible other fields.

</DOC>
<DOC>
<DOCNO> 150586 </DOCNO>
Superspace Representations of SU(2,2/N) Superalgebras and Multiplet


  We derive massless and massive representations of all SU(2,2/N) superalgebras
by using superfields defined in "harmonic superspace". This method allows one
to easily construct "short superfields" which are relevant in the analysis of
the AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 83327 </DOCNO>
Computational Geometry Column 39


  The resolution of a decades-old open problem is described: polygonal chains
cannot lock in the plane.

</DOC>
<DOC>
<DOCNO> 69759 </DOCNO>
Relic Neutrino Asymmetries


  I review the topic of relic neutrino asymmetry generation through
active-sterile neutrino and antineutrino oscillations in the early universe.
Applications to (i) the suppression of sterile neutrino production, and (ii)
the primordial Helium abundance are briefly presented.

</DOC>
<DOC>
<DOCNO> 13429 </DOCNO>
1.26 $\mu$m intersubband transitions in In$_{0.3}$Ga$_{0.7}$As/AlAs


  We observed room-temperature intersubband transitions at 1.26 microns in
n-doped type-II In$_{0.3}$Ga$_{0.7}$As/AlAs strained quantum wells. An improved
tight-binding model was used to optimize the structure parameters in order to
obtain the shortest wavelength intersubband transition ever achieved in a
semiconductor system. The corresponding transitions occur between the first
confined electronic levels of the well following mid-infrared optical pumping
of electrons from the barrier X-valley into the well ground state.

</DOC>
<DOC>
<DOCNO> 12852 </DOCNO>
Specific Heat Study of the Field-Induced Magnetic Ordering in the Spin


  Specific heat measurements have been performed in the coupled dimer system
TlCuCl$_3$, which has a singlet ground state with the excitation gap $\Delta
\simeq 7.5$K. The cusplike anomaly indicative of the 3D magnetic ordering was
clearly observed in magnetic fields higher than the critical field $H_c$
corresponding to the gap $\Delta$. The phase boundary determined by the present
specific heat measurements coincides with that determined by previous
magnetization measurements. The phase boundary can be described by the power
law $[ H_{\rm c}(T)-H_{\rm g} ] \propto T^{\phi}$ with $\phi=2.1(1)$. This
result supports the magnon Bose condensation picture for the field-induced
magnetic ordering in TlCuCl$_3$ [Nikuni {\it et al}., Phys. Rev. Lett. {\bf 84}
(2000) 5868].

</DOC>
<DOC>
<DOCNO> 123095 </DOCNO>
Cold H2O and CO ice and gas toward the Galactic Center


  We present observations of CO, 13CO and of H2O in the middle and far-infrared
taken with the ISO-SWS and ISO-LWS spectrometers toward two positions in the
Galactic Center region (Sgr A* and GCS-3). Both ice and gas phase molecules are
detected. The ISO data have been complemented with observations of the J=3-2
and J=7-6 lines of CO carried out at the Caltech Submillimeter Observatory. The
ISO and CSO data indicate that the absorbing gas is extremely cold, T_K ~ 10 K,
suggesting that it is located in the dark clouds of the different spiral arms
that intersect the line of sight towards the Galactic Center. From the analysis
of the CO absorption we derive 13CO gas phase column densities of 1.1 and
0.7E17 cm-2 towards Sgr A* and GCS-3, respectively. The H2O gas column density
in the direction of Sgr A* is ~ 2E16 cm-2. The derived CO/H2O and gas/solid
abundance ratios corresponding to these cold clouds are remarkably similar
along the two lines of sight. We find that nearly all the CO is in the gas
phase, while the H2O is almost entirely frozen onto the surfaces of cold dust
grains. Finally, the N_{gas+ice}(CO)/N_{gas+ice}(H2O) abundance ratio is ~5
implying that H2O formation processes are highly efficient.

</DOC>
<DOC>
<DOCNO> 9090 </DOCNO>
Current and power spectrum in a magnetic tunnel device with an atomic


  Current and its noise in a ferromagnetic double tunnel barrier device with a
small spacer particle were studied in the framework of the sequential tunneling
approach. Analytical formulae were derived for electron tunneling through the
spacer particle containing only a single energy level. It was shown that
Coulomb interactions of electrons with a different spin orientation lead to an
increase of the tunnel magnetoresistance. Interactions can also be responsible
for the negative differential resistance. A current noise study showed, which
relaxation processes can enhance or reduce fluctuations leading either to a
super-Poissonian or a sub-Poissonian shot noise.

</DOC>
<DOC>
<DOCNO> 69149 </DOCNO>
Limits on Neutrino Masses from Large-Scale Structure


  Massive neutrinos have a detectable effect on cosmological structure
formation, in particular on the large-scale distribution of galaxies. Adding
Hot Dark Matter to the now-standard Lambda CDM model leads to a worse fit to
large-scale structure and CMB anisotropy data. This results in a limit on the
mass of the most massive neutrino of 4 eV, assuming a power-law primordial
power spectrum.

</DOC>
<DOC>
<DOCNO> 170562 </DOCNO>
q-deformed dynamics and Josephson junction


  We define a generalized rate equation for an observable in quantum mechanics,
that involves a parameter q and whose limit $q\to 1$ gives the standard
Heisenberg equation. The generalized rate equation is used to study dynamics of
current biased Josephson junction. It is observed that this toy model
incorporates diffraction like effects in the critical current. Physical
interpretation for q is provided which is also shown to be q-deformation
parameter.

</DOC>
<DOC>
<DOCNO> 39702 </DOCNO>
Search for Nucleon Decay with Final States l+ eta, nubar eta, and nubar


  We have searched for nucleon decay into five two-body final states using a
4.4 kiloton-year fiducial exposure of the Soudan 2 iron tracking calorimeter.
For proton decay into the fully visible final states mu+ eta and e+ eta, we
observe zero and one event, respectively, that satisfy our search criteria for
nucleon decay. The lifetime lower limits (tau/B) thus implied are 89 x 10^30
years and 81 x 10^30 years at 90% confidence level. For neutron decay into
nubar eta, we obtain the lifetime lower limit 71 x 10^30 years. Limits are also
reported for neutron decay into nubar pi0, and for proton decay into nubar pi+.

</DOC>
<DOC>
<DOCNO> 120941 </DOCNO>
Lyman Continuum Emission from Galaxies at z~3.4


  We report the detection of significant Lyman continuum flux in the composite
spectrum of 29 Lyman break galaxies (LBGs) with redshifts <z> = 3.40+/-0.09.
After correction for opacity due to intervening absorption using a new
composite QSO spectrum evaluated at the same redshift, the ratio of emergent
flux density at 1500 \AA in the rest frame to that in the Lyman continuum is
L(1500)/L(900) = 4.6 +/- 1.0. If the relative intensity of the inferred
escaping Lyman continuum radiation is typical of LBGs at z ~ 3 (the galaxies in
this sample are drawn from the bluest quartile of LBG spectral energy
distributions due to known selection effects), then observed LBGs produce about
5 times more H-ionizing photons per unit co-moving volume than QSOs at z ~ 3.
The associated contribution to the metagalactic ionizing radiation field is
J_{\nu}(912) = 1.2+/-0.3 x 10^{-21} ergs s^{-1} cm^{-2} Hz^{-1} sr^{-1} at z ~
3, very close to most estimates of the radiation field background based on the
``proximity effect''. A preliminary analysis of the density of faint QSOs in
our Lyman break galaxy survey indicates that the standard extrapolated QSO
luminosity function may slightly over-predict the QSO contribution to
J_{\nu}(912) at z ~ 3. We briefly discuss the implications of a
galaxy-dominated UV background at high redshifts.

</DOC>
<DOC>
<DOCNO> 119511 </DOCNO>
Molecular Gas and Star Formation in the Host Galaxy of I Zw 1


  A recent analysis of high angular resolution NIR imaging and spectroscopic
data in conjunction with Plateau de Bure interferometric mm-line observations
indicate the presence of a circum-nuclear starburst ring of about 1.5 arcsec
(1.5 kpc) diameter in I Zw 1. High angular resolution NIR imaging, using the
MPE SHARP camera at the ESO NTT, HST V-band images, as well as NIR spectroscopy
with MPE 3D provide an improved analysis of the star formation activity in the
disk and nucleus of I Zw 1. We present first results from subarcsecond
interferometric imaging in the 12CO(2-1) line using the Plateau de Bure
Interferometer.

</DOC>
<DOC>
<DOCNO> 170556 </DOCNO>
Observation of Ultraslow Group Velocity of Light in a Solid


  We report ultraslow group velocities of light in a solid. Light speeds as
slow as 45 m/s were observed, corresponding to a group delay of 66 ms in a 3-mm
thick crystal. Reduction of the group velocity is accomplished by using a sharp
spectral feature in absorption and dispersion, produced by a Raman excited spin
coherence in an optically dense Pr doped Y2SiO5 crystal.

</DOC>
<DOC>
<DOCNO> 85011 </DOCNO>
Experimental feasibility of measuring the gravitational redshift of


  This paper describes a new class of experiments that use dispersion in
optical fibers to convert the gravitational frequency shift of light into a
measurable phase shift or time delay. Two conceptual models are explored. In
the first model, long counter-propagating pulses are used in a vertical fiber
optic Sagnac interferometer. The second model uses optical solitons in
vertically separated fiber optic storage rings. We discuss the feasibility of
using such an instrument to make a high precision measurement of the
gravitational frequency shift of light.

</DOC>
<DOC>
<DOCNO> 101630 </DOCNO>
Algorithms for Greechie Diagrams


  We give a new algorithm for generating Greechie diagrams with arbitrary
chosen number of atoms or blocks (with 2,3,4,... atoms) and provide a computer
program for generating the diagrams. The results show that the previous
algorithm does not produce every diagram and that it is at least 100,000 times
slower. We also provide an algorithm and programs for checking of Greechie
diagram passage by equations defining varieties of orthomodular lattices and
give examples from Hilbert lattices. At the end we discuss some additional
characteristics of Greechie diagrams.

</DOC>
<DOC>
<DOCNO> 170326 </DOCNO>
Strictly isospectral potentials from excited quantum states


  The strictly nonrelativistic isospectral scheme based on the general Riccati
solution and Darboux transformation function corresponding to excited states is
presented on the following examples: the harmonic oscillator, the square well,
and the hydrogen atom

</DOC>
<DOC>
<DOCNO> 9684 </DOCNO>
Mean Field Critical Behaviour for a Fully Frustrated


  We present a mean field analysis of a fully frustrated Ising spin model on an
Ising lattice gas. This is equivalent to a degenerate Blume-Emery-Griffiths
model with frustration, which we analyze for different values of the
quadrupolar interaction. This model might be useful in the study of structural
glasses and related systems with disorder.

</DOC>
<DOC>
<DOCNO> 8100 </DOCNO>
Characterization of ferrimagnetic Heisenberg chains according to the


  The low-energy structure and the thermodynamic properties of ferrimagnetic
Heisenberg chains of alternating spins $S$ and $s$ are investigated by the use
of numerical tools as well as the spin-wave theory. The elementary excitations
are calculated through an efficient quantum Monte Carlo technique featuring
imaginary-time correlation functions and are characterized in terms of
interacting spin waves. The thermal behavior is analyzed with particular
emphasis on its ferromagnetic and antiferromagnetic dual aspect. The extensive
numerical and analytic calculations lead to the classification of the
one-dimensional ferrimagnetic behavior according to the constituent spins: the
ferromagnetic ($S>2s$), antiferromagnetic ($S<2s$), and balanced ($S=2s$)
ferrimagnetism.

</DOC>
<DOC>
<DOCNO> 11172 </DOCNO>
Ab initio evaluation of local effective interactions in $\alpha^\prime


  We will present the numerical evaluation of the hopping and magnetic exchange
integrals for a nearest-neighbor $t-J$ model of the quarter-filled
$\alpha^\prime NaV_2O_5$ compound. The effective integrals are obtained from
valence-spectroscopy {\em ab initio} calculations of embedded crystal fragments
(two $VO_5$ pyramids in the different geometries corresponding to the desired
parameters). We are using a large configurations interaction (CI) method, where
the CI space is specifically optimized to obtain accurate energy differences.
We show that the $\alpha^\prime NaV_2O_5$ system can be seen as a
two-dimensional asymmetric triangular Heisenberg lattice where the effective
sites represent delocalized $V-O-V$ rung entities supporting the magnetic
electrons.

</DOC>
<DOC>
<DOCNO> 150785 </DOCNO>
Chiral Random Matrix Model for Critical Statistics


  We propose a random matrix model that interpolates between the chiral random
matrix ensembles and the chiral Poisson ensemble. By mapping this model on a
non-interacting Fermi-gas we show that for energy differences less than a
critical energy $E_c$ the spectral correlations are given by chiral Random
Matrix Theory whereas for energy differences larger than $E_c$ the number
variance shows a linear dependence on the energy difference with a slope that
depends on the parameters of the model. If the parameters are scaled such that
the slope remains fixed in the thermodynamic limit, this model provides a
description of QCD Dirac spectra in the universality class of critical
statistics. In this way a good description of QCD Dirac spectra for gauge field
configurations given by a liquid of instantons is obtained.

</DOC>
<DOC>
<DOCNO> 85379 </DOCNO>
Non-Anticommutative Quantum Gravity


  A calculation of the one loop gravitational self-energy graph in
non-anticommutative quantum gravity reveals that graviton loops are damped by
internal momentum dependent factors in the modified propagator and the vertex
functions. The non-anticommutative quantum gravity perturbation theory is
finite for matter-free gravity and for matter interactions.

</DOC>
<DOC>
<DOCNO> 71292 </DOCNO>
Cosmological thermodynamics and deflationary gas universe


  We establish a general thermodynamic scheme for cosmic fluids with internal
self-interactions and discuss equilibrium and non-equilibrium aspects of such
systems in connection with (generalized) symmetry properties of the
cosmological dynamics. As an example we construct an exactly solvable gas
dynamical model of a ``deflationary'' transition from an initial de Sitter
phase to a subsequent Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) period.
We demonstrate that this dynamics represents a manifestation of a conformal
symmetry of an ``optical'' metric, characterized by a specific effective
refraction index of the cosmic medium.

</DOC>
<DOC>
<DOCNO> 11759 </DOCNO>
Density functional formalism in the canonical ensemble


  Density functional theory, when applied to systems with $T\neq 0$, is based
on the grand canonical extension of the Hohenberg-Kohn-Sham theorem due to
Mermin (HKSM theorem). While a straightforward canonical ensemble
generalization fails, work in nanopore systems could certainly benefit from
such extension. We show that, if the asymptotic behaviour of the canonical
distribution functions is taken into account, the HKSM theorem can be extended
to the canonical ensemble. We generate $N$-modified correlation and
distribution functions hierarchies and prove that, if they are employed, either
a modified external field or the density profiles can be indistinctly used as
independent variables. We also write down the $N$% -modified free energy
functional and prove that its minimum is reached when the equilibrium values of
the new hierarchy are used. This completes the extension of the HKSM theorem.

</DOC>
<DOC>
<DOCNO> 178621 </DOCNO>
Three-Nucleon Forces for the New Millennium


  Most nuclear physics ranges from insensitive to relatively insensitive to
many-nucleon forces. The dominant ingredient in calculations of nuclear
properties is the nucleon-nucleon potential. Three-nucleon forces nevertheless
play an important role in nuclear physics because of the great precision of
modern calculational methods for systems of relatively few nucleons. We explore
the reasons why many-body forces are weak in nuclei by using a classification
scheme for such forces that is based on dimensional power counting, which is
used to organize chiral perturbation theory. An assessment will be made of how
close we are to a ``standard'' three-nucleon force. Recent advances in
determining the significance of three-nucleon forces will also be discussed.

</DOC>
<DOC>
<DOCNO> 80716 </DOCNO>
Exact local fermionic zero modes


  We introduce a simple method to find localized exact fermionic zero modes for
any local fermionic action. The zero modes are attached to specific local gauge
configurations. Examples are provided for staggered and Wilson fermion actions
in 2-6 dimensions, at finite and infinite lattice volumes, and for abelian and
non-abelian gauge groups. One of our concrete results is that a finite density
of almost zero modes must occur in quenched four dimensional lattice gauge
theory simulations that use traditional methods. This density is exponentially
suppressed in the gauge coupling constant.

</DOC>
<DOC>
<DOCNO> 102130 </DOCNO>
Symplectic Structures on Fiber Bundles


  Let $\pi: P\to B$ be a locally trivial fiber bundle over a connected CW
complex $B$ with fiber equal to the closed symplectic manifold $(M,\om)$. Then
$\pi$ is said to be a symplectic fiber bundle if its structural group is the
group of symplectomorphisms $\Symp(M,\om)$, and is called Hamiltonian if this
group may be reduced to the group $\Ham(M,\om)$ of Hamiltonian
symplectomorphisms. In this paper, building on prior work by Seidel and
Lalonde, McDuff and Polterovich, we show that these bundles have interesting
cohomological properties. In particular, for many bases $B$ (for example when
$B$ is a sphere, a coadjoint orbit or a product of complex projective spaces)
the rational cohomology of $P$ is the tensor product of the cohomology of $B$
with that of $M$. As a consequence the natural action of the rational homology
$H_k(\Ham(M))$ on $H_*(M)$ is trivial for all $M$ and all $k > 0$.

</DOC>
<DOC>
<DOCNO> 118678 </DOCNO>
Calculation Methods for Radio Pulses from High Energy Showers


  We present an approximation for the numerical calculation of Cherenkov radio
pulses in the Fraunhofer limit from very high energy showers in dense media. We
compare it to full Montecarlo simulations in ice studying its range of
applicability and show how it can be extended with a simple algorithm. The
approximation reproduces well the angular distribution of the pulse around the
Cherenkov direction. An improved parameterization for the frequency spectrum in
the Cherenkov direction is given for phenomenolgical applications. We extend
the method to study the pulses produced by showers at distances at which the
Fraunhofer limit does not apply, and give the ranges of distances and
frequencies in which Fraunhofer approximation is good enough for interpreting
future experimental data. Our results are relevant for the detection of very
high energy neutrinos with this technique.

</DOC>
<DOC>
<DOCNO> 13301 </DOCNO>
Critical Phenomena: An Introduction from a modern perspective


  Our aim in this set of lectures is to give an introduction to critical
phenomena that emphasizes the emergence of and the role played by diverging
length-scales. It is now accepted that renormalization group gives the basic
understanding of these phenomena and so, instead of following the traditional
historical trail, we try to develop the subject in a way that emphasizes the
length-scale based approach.

</DOC>
<DOC>
<DOCNO> 121484 </DOCNO>
Selection effects in high-redshift submillimeter surveys and pointed


  The results of the first generation of submillimeter-wave surveys have been
published. The opening of this new window on the distant Universe has added
considerably to our understanding of the galaxy formation process, by revealing
a numerous population of very luminous distant galaxies. Most would have been
very difficult to identify using other methods. The potential importance of
selection effects, especially those connected with the spectral energy
distributions of the detected galaxies, for the interpretation of the results
are highlighted.

</DOC>
<DOC>
<DOCNO> 169874 </DOCNO>
RISQ - reduced instruction set quantum computers


  Candidates for quantum computing which offer only restricted control, e.g.,
due to lack of access to individual qubits, are not useful for general purpose
quantum computing. We present concrete proposals for the use of systems with
such limitations as RISQ - reduced instruction set quantum computers and
devices - for simulation of quantum dynamics, for multi-particle entanglement
and squeezing of collective spin variables. These tasks are useful in their own
right, and they also provide experimental probes for the functioning of quantum
gates in pre-mature proto-types of quantum computers.

</DOC>
<DOC>
<DOCNO> 120476 </DOCNO>
A Cyclic Universe without Missing Mass: Implications of R->alpha'/R


  Results from string theory conclude that a spatial dimension R is equivalent
to *'/R. If R is considered as a four-space dimension, several interesting
results emerge. In this paradigm, *'/R exists in a time-reversed, "anti-
parallel" universe. Cosmological distances in our real-time universe are
equivalent to the compact dimensions at the instant of a Big Bang in a time-
inverted universe. This model agrees with standard black hole theory in that
particles become frozen in time when they reach the 'singularity' (of dimension
alpha'). A particle which enters a black hole in real time exits from the Big
Bang or "white hole" in the time-inverted universe, leaving behind a trace of
annihilation radiation. A diagram of this phenomenon is constructed, consistent
with existing knowledge of the early universe. The primordeal black holes
predicted by Hawking are required. A cyclic universe is described by M^2\p,n +
T^2\n = 1. The "missing mass" proscribed by standard closed- universe theories
is not required. This result is useful if experimental evidence in the search
for dark matter continues to leave a significant "missing mass" - and
particularly in light of more recent observations indicating that, in fact,
inflation continues at a much reduced rate.

</DOC>
<DOC>
<DOCNO> 99866 </DOCNO>
Projective generation and smoothness of congruences of order 1


  In this paper we give the projective generation of congruences of order 1 of
r-dimensional projective spaces in P^N from their focal loci. In a natural way,
this construction shows that the corresponding surfaces in the grassmannian are
the Veronese surface, and rational ruled surfaces eventually with
singularities. We characterize when these surfaces are smooth, recovering and
generalizing a Ziv Ran's result.

</DOC>
<DOC>
<DOCNO> 69046 </DOCNO>
Infrared alignment of SUSY flavor structures


  The various experimental bounds on flavor-changing interactions severely
restrict the low-energy flavor structures of soft supersymmetry breaking
parameters. In this work, we show that with a particular assumption of Yukawa
couplings, the fermion mass and sfermion soft mass matrices are simultaneously
diagonalized by common mixing matrices and we then obtain an alignment solution
for the flavor problems. The required condition is generated by renormalization
group evolutions and achieved at low-energy scale independently of high-energy
structures of couplings. In this case, the diagonal entries of the soft scalar
mass matrices are determined by gaugino and Higgs soft masses. We also discuss
possible realizations of this scenario and the characteristic sparticle
spectrum in the models.

</DOC>
<DOC>
<DOCNO> 12786 </DOCNO>
Lattice Boltzmann Simulations of Liquid Crystal Hydrodynamics


  We describe a lattice Boltzmann algorithm to simulate liquid crystal
hydrodynamics. The equations of motion are written in terms of a tensor order
parameter. This allows both the isotropic and the nematic phases to be
considered. Backflow effects and the hydrodynamics of topological defects are
naturally included in the simulations, as are viscoelastic properties such as
shear-thinning and shear-banding.

</DOC>
<DOC>
<DOCNO> 10339 </DOCNO>
Correlation structure of extreme stock returns


  It is commonly believed that the correlations between stock returns increase
in high volatility periods. We investigate how much of these correlations can
be explained within a simple non-Gaussian one-factor description with time
independent correlations. Using surrogate data with the true market return as
the dominant factor, we show that most of these correlations, measured by a
variety of different indicators, can be accounted for. In particular, this
one-factor model can explain the level and asymmetry of empirical exceedance
correlations. However, more subtle effects require an extension of the one
factor model, where the variance and skewness of the residuals also depend on
the market return.

</DOC>
<DOC>
<DOCNO> 68067 </DOCNO>
Measuring Higgs boson couplings at the LHC


  For an intermediate mass Higgs boson with SM-like couplings the LHC allows
observation of a variety of decay channels in production by gluon fusion and
weak boson fusion. Cross section ratios provide measurements of various ratios
of Higgs couplings, with accuracies of order 15% for 100 fb^{-1} of data in
each of the two LHC experiments. For Higgs masses above 120 GeV, minimal
assumptions on the Higgs sector allow for an indirect measurement of the total
Higgs boson width with an accuracy of 10 to 20%, and of the H-->WW partial
width with an accuracy of about 10%.

</DOC>
<DOC>
<DOCNO> 151148 </DOCNO>
N=2 super-Born-Infeld theory revisited


  I discuss the symmetry structure of the N=2 supersymmetric extension of the
Born-Infeld action in four dimensions, and confirm its interpretation as the
Goldstone-Maxwell action associated with partial breaking of N=4 extended
supersymmetry down to N=2, by revealing a hidden invariance of the action with
respect to two non-linearly realized supersymmetries and two spontaneously
broken translations. I also argue about the uniqueness of supersymmetric
extension of the Born-Infeld action, and its possible relation to
noncommutative geometry.

</DOC>
<DOC>
<DOCNO> 102018 </DOCNO>
A Convex decomposition theorem for four-manifolds


  We show that every smooth closed oriented four-manifold admits a
decomposition into two co- dimension zero submanifolds with common boundary.
Each of these submanifolds carries a structure of a symplectic manifold with
pseudo-convex boundary.
  This imply, in particular, that every smooth closed simply-connected
four-manifold is a Stein domain in the the complement of a certain contractible
2-complex.

</DOC>
<DOC>
<DOCNO> 152311 </DOCNO>
Connes' Gauge Theory on Noncommutative Space-Times


  Connes' gauge theory is defined on noncommutative space-times. It is applied
to formulate a noncommutative Glashow-Weinberg-Salam (GWS) model in the
leptonic sector. It is shown that the model has two Higgs doublets and the
gauge bosons sector after the Higgs mechanism contains the massive charged
gauge fields, two massless and two massive neutral gauge fields. It is also
shown that, in the tree level, the neutrino couples to one of two `photons',
the electron interacts with both `photons' and there occurs a nontrivial
$\nu_R$-interaction on noncommutative space-times. Our noncommutative GWS model
is reduced to the GWS theory in the commutative limit. Thus in the neutral
gauge bosons sector there are only one massless photon and only one $Z^0$ in
the commutative limit.

</DOC>
<DOC>
<DOCNO> 118092 </DOCNO>
A Comparison of Ultraviolet, Optical, and X-Ray Imagery of Selected


  During the Astro-1 and Astro-2 Space Shuttle missions in 1990 and 1995, far
ultraviolet (FUV) images of five 40' diameter fields around the rim of the
Cygnus Loop supernova remnant were observed with the Ultraviolet Imaging
Telescope (UIT). These fields sampled a broad range of conditions including
both radiative and nonradiative shocks in various geometries and physical
scales. In these shocks, the UIT B5 band samples predominantly CIV 1550 and the
hydrogen two-photon recombination continuum. Smaller contri- butions are made
by emission lines of HeII 1640 and OIII] 1665. We present these new FUV images
and compare them with optical Halpha and [OIII], and ROSAT HRI X-ray images.
Comparing the UIT images with those from the other bands provides new insights
into the spatial variations and locations of these different types of emission.
By comparing against shock model calculations and published FUV spectroscopy at
select locations, we surmise that resonance scattering in the strong FUV
permitted lines is widespread in the Cygnus Loop, especially in the bright
optical filaments typically selected for observation in most previous studies.

</DOC>
<DOC>
<DOCNO> 10115 </DOCNO>
The spectral properties of non-condensate particles in Bose-condensed


  The strong spin-dipole relaxation, accompanying BEC in a gas of atomic
hydrogen, determines the formation of a quasistationary state with a flux of
particles in energy space to the condensate. This state is characterized by a
significant enhancement of the low-energy distribution of non-condensate
particles resulting in a growth of their spatial density in the trap. This
growth leads to the anomalous reconstruction of the optical spectral properties
of non-condensate particles.

</DOC>
<DOC>
<DOCNO> 71985 </DOCNO>
Nucleon resonances in polarized omega photoproduction


  The role of the nucleon resonances ($N^*$) in $\omega$ photoproduction is
investigated by using the resonance parameters predicted by Capstick and
Roberts. The contributions from the nucleon resonances are found to be
significant in various spin asymmetries. In particular, we found that a crucial
test of our predictions can be made by measuring the parity asymmetry and
beam-target double asymmetry at forward scattering angles.

</DOC>
<DOC>
<DOCNO> 119294 </DOCNO>
The Abundance of Interstellar Boron


  We use new Space Telescope Imaging Spectrograph (STIS) and archival Goddard
High Resolution Spectrograph (GHRS) observations to study interstellar B II
1362 and O I 1355 absorption along seven sightlines. Our new column density
measurements, combined with measurements of four sightlines from the
literature, allow us to study the relative B/O abundances over a wide range of
interstellar environments. We measure sightline-integrated relative gas-phase
abundances in the range [B/O] = -1.00 to -0.17, and our data show the B/O
abundances are anticorrelated with average sightline densities over the range
log <n_H> ~ -1.3 to +0.7. Detailed comparisons of the B II and O I line shapes
show that the B/O ratio is significantly higher in warm interstellar clouds
than in cool clouds. These results are consistent with the incorporation of
boron into dust grains in the diffuse ISM. Since boron is likely incorporated
into grains, we derive a lower limit to the present-day total (gas+dust)
interstellar boron abundance of B/H > (2.5+/-0.9)x10^-10. The effects of dust
depletion and ionization differences from element to element will make it very
difficult to reliably determine 11B/10B along most interstellar sightlines.

</DOC>
<DOC>
<DOCNO> 102153 </DOCNO>
Symplectic geometry and the uniqueness of Grauert tubes


  A compact real analytic Riemannian manifold M admits a canonical
complexification with plurisubharmonic exhaustion function satisfying the
homogeneous complex Monge-Ampere equation, called a Grauert tube. From the
point of view of complex analysis, several authors have considered whether a
given complex manifold can arise in more than one way from this construction.
We show that given a compact M and a finite exhaustion, the underlying
Riemannian structure is unique. The proof uses the technique of holomorphic
disks spanning two exact Lagrangian submanifolds of the cotangent bundle of M,
and Schwarz reflection.

</DOC>
<DOC>
<DOCNO> 71594 </DOCNO>
Strong interactions of light flavours


  After an introduction to chiral perturbation theory, the effective field
theory of the standard model at low energies, a brief overview is given of
applications to light-flavour physics. Three topics in the strong interactions
of pseudoscalar mesons are then discussed in some detail: loops and chiral
logs, pion-pion scattering and isospin violation.

</DOC>
<DOC>
<DOCNO> 122799 </DOCNO>
A search for possible interactions between ejections from GRS 1915+105


  We have observed an extended region surrounding the first discovered galactic
superluminal source GRS 1915+105, seeking evidence of interaction between the
relativistic ejecta of that object and the interstellar medium. We find two
radio sources axisymmetrically aligned along the sub-arcsecond relativistic
ejecta of GRS 1915+105 and roughly 17' distant from it, which coincide with the
luminous IRAS sources 19124+1106 and 19132+1035. We have observed these sources
at centimeter (VLA), millimeter (IRAM 30m), and infrared (ISO, UKIRT, ESO/MPI
2.2m) wavelengths in both line and continuum emission. At centimeter
wavelengths a non-thermal jet-like feature aligned along the outflow axis is
located adjacent to the inner edge of the southern source. Strong density
enhancements are found in the millimeter tracers CO and H13CO+ at the positions
of both sources and some of the morphology is reminiscent of shock-like
interactions; however, linewidths are narrow. At infrared wavelengths strong
hydrogen recombination lines and weak lines of molecular hydrogen are observed
at the southern source. We discuss these results as possible evidence of the
sought-after interaction, both in terms of the regions undergoing ongoing
shock-heating and in terms of them being locations of shock-induced star
formation. The evidence for each of these is inconclusive. Millimeter line
mapping of a portion of W 50 where the relativistic jets of the X-ray binary SS
433 interact with the interstellar medium shows roughly similar morphology as
GRS 1915+105, suggesting that the phenomena observed at the IRAS sources may
not be unusual for such a long distance interaction.

</DOC>
<DOC>
<DOCNO> 68834 </DOCNO>
Fermions obstruct dimensional reduction in hot QCD


  We have studied, for the first time, screening masses obtained from
glueball-like correlators in Quantum Chromodynamics with four light dynamical
flavours of quarks in the temperature range 1.5T_c < T < 3T_c, where T_c is the
temperature at which the chiral transition occurs. We have also studied
pion-like and sigma-like screening masses, and found that they are degenerate
in the entire range of T. These obstruct perturbative dimensional reduction
since the lowest glueball screening mass is heavier than them. Extrapolation of
our results suggests that this obstruction may affect the entire range of
temperature expected to be reached even at the Large Hadron Collider.

</DOC>
<DOC>
<DOCNO> 120226 </DOCNO>
Extreme Galactic-Winds and Starburst in IR Mergers and IR QSOs


  We report -as a part of a long-term study of mergers and IR QSOs- detailed
spectroscopic evidences for outflow (OF) and/or Wolf Rayet features in: (i) low
velocity OF in the ongoing mergers NGC 4038/39 and IRAS 23128-5919; (ii)
extreme velocity OF (EVOF) in the QSOs IRAS 01003-2238 and IRAS 13218+0552;
(iii) OF and EVOF in a complete sample of ultra-luminous IR galaxies/QSOs ("The
IRAS 1 Jy MKO-KPNO Survey", of 118 objects). We found EVOF in IRAS 11119+3257,
14394+5332, 15130+1958 and 15462-0450. The OF components detected in these
objects were mainly associated to starburst processes: i.e., to galactic-winds
generated in multiple type II SN explosions and massive stars. The EVOF were
detected in objects with strong starburst plus obscured IR QSOs; which suggest
that interaction of both processes could generate EVOF. In addition, we analyze
the presence of Wolf Rayet features in the large sample of Bright PG-QSOs
(Boroson and Green 1992), and nearby mergers and galactic-wind galaxies. We
found clear WR features in the Fe II QSOs (type I): PG 1244+026, 1444+407,
1448+273, 1535+547; and in the IR merger Arp 220. HST archive images of IR+BAL
QSOs show in practically all of these objects "arc or shell" features probably
associated to galactic-winds (i.e., to multiple type II SN explosions) and/or
merger processes. Finally, we discuss the presence of extreme starburst and
galactic wind as a possible evolutive link between IR merger and IR QSOs; where
the relation between mergers and extreme starburst (with powerful
galactic-winds) plays in important role, in the evolution of galaxies.

</DOC>
<DOC>
<DOCNO> 121836 </DOCNO>
Gamma-ray burst afterglows from jetted shocks in wind environments


  Gamma-ray bursts with long durations are widely thought to arise from the
collapse of massive stars, where the wind environment is unavoidable. It is
also believed that $\gamma$-ray bursts come from jets. Considering these two
points in this paper, we calculate the evolution of a highly collimated jet
that expands in a stellar wind environment and the expected afterglow from such
a jet. We use a set of refined dynamical equations and a realistic lateral
speed of the jet, and find: (1) There is no observable break at the time when
the Lorentz factor of the jet is equal to the inverse of its initial
half-opening angle. (2) No obvious break appears at the time when the blast
wave transits from the relativistic to the non-relativistic phase. (3) For the
wind case, there is no flattening tendency even up to $10^9$ s. (4) Compared
with the homogeneous medium case, our calculated flux is weaker in the stellar
wind case. Finally, we find that two kinds of GRB models (neutron star mergers
and massive star collapses) may be discriminated in our numerical results.

</DOC>
<DOC>
<DOCNO> 178807 </DOCNO>
Discontinuities in Relativistic Hydrodynamics Across Space-like and


  Discontinuities in relativistic hydrodynamics - shock waves and freeze-out
shocks - are considered across both space-like and time-like hypersurfaces. We
analyze the peculiar features of the freeze-out discontinuities and their
connection to the shock-wave phenomena.

</DOC>
<DOC>
<DOCNO> 68523 </DOCNO>
Vacuum Energy: "If Not Now, Then When?"


  For a flat universe presently dominated by static or dynamic vacuum energy,
cosmological constant (LCDM) or quintessence (QCDM), we calculate the
asymptotic collapsed mass fraction as function of the present ratio of smooth
energy to matter energy $\rat=(1-\omm)/\omm$. Identifying these collapsed
fractions as anthropic probabilities, we find the observed present ratio $\rat
\sim 2$ to be likely in LCDM, but most likely in QCDM.

</DOC>
<DOC>
<DOCNO> 11886 </DOCNO>
Zero-Bias States and the Mechanism of the Surface d->d+is Transition


  We study the physical mechanism of the surface d->d+is transition proposed as
the interpretation of results of tunneling experiments into ab planes. We base
our argument on first-order perturbation theory and show that the zero-bias
states drive the transition. We support the argument by various estimates and
consistency checks.

</DOC>
<DOC>
<DOCNO> 99464 </DOCNO>
The trace formula for transversally elliptic operators on Riemannian


  We prove a Duistermaat-Guillemin trace formula for transversally elliptic
operators on a compact foliated manifold.

</DOC>
<DOC>
<DOCNO> 102227 </DOCNO>
Necklace Lie algebras and noncommutative symplectic geometry


  Recently V. Ginzburg proved that Calogero phase space is a coadjoint orbit
for some infinite dimensional Lie algebra coming from noncommutative symplectic
geometry. In this note we generalize this argument to specific quotient
varieties of representations of (deformed) preprojective algebras. This result
was also obtained independently by V. Ginzburg.

</DOC>
<DOC>
<DOCNO> 102798 </DOCNO>
Bialgebroids, $\times_{A}$-bialgebras and duality


  An equivalence between Lu's bialgebroids, Xu's bialgebroids with an anchor
and Takeuchi's $\times_{A}$-bialgebras is explicitly proven. A new class of
examples of bialgebroids is constructed. A (formal) dual of a bialgebroid,
termed bicoalgebroid, is defined. A weak Hopf algebra is shown to be an example
of such a bicoalgebroid.

</DOC>
<DOC>
<DOCNO> 119527 </DOCNO>
Optical Monitoring of NLS1s at the Wise Observatory


  We report the preliminary results of a spectrophotometric monitoring program
of Narrow-Line Seyfert 1 galaxies conducted at the Wise Observatory in 1999.
The data we collected will be used to evaluate the line-to-continuum time lag
in an attempt to test the idea that the accretion rate in NLS1s is larger than
in other Seyfert 1 galaxies.

</DOC>
<DOC>
<DOCNO> 151427 </DOCNO>
Double-vector multiplet and partially broken N=4, d=3 supersymmetry


  We elaborate on a new N=2, d=3 supermultiplet (double-vector multiplet) with
a non-trivial off-shell realization of the central charge. Its bosonic sector
comprises two abelian gauge vector fields forming an SO(2) vector. We present a
superfield formulation of this multiplet in the central-charge extended N=2,
d=3 superspace and then employ it, in the framework of the nonlinear
realizations approach, as the Goldstone one for the partial breaking N=4 -> N=2
in three dimensions. The covariant equations of motion for the self-interacting
Goldstone superfield arise as a natural generalization of the free ones and are
interpreted as the worldvolume supersymmetric form of the equations of motion
of a N=4 D2-brane. For the vector fields we find a coupled nonlinear system of
Born-Infeld type and demonstrate its dual equivalence to the d=5 membrane. The
double-vector multiplet can be fused with some extra N=2, d=3 multiplet to form
an off-shell N=4, d=3 supermultiplet.

</DOC>
<DOC>
<DOCNO> 12930 </DOCNO>
Muffin Tin Orbitals of Arbitrary Order


  We have derived orbital basis sets from scattering theory. They are expressed
as polynomial approximations to the energy dependence of a set of partial
waves, in quantized form. The corresponding matrices, as well as the
Hamiltonian and overlap matrices, are specified by the values on the energy
mesh of the screened resolvent and its first energy derivative. These orbitals
are a generalization of the 3rd-generation linear MTOs and should be useful for
electronic-structure calculations in general.

</DOC>
<DOC>
<DOCNO> 123337 </DOCNO>
Characteristics of Astronomy-Related Organizations


  Geographical distributions, ages and sizes of astronomy-related organizations
have been investigated from comprehensive and up-to-date samples extracted from
the master files for StarGuides/StarWorlds. Results for professional
institutions, associations, planetariums, and public observatories are
commented, as well as specific distributions for astronomy-related publishers
and commercial-software producers.
  The highly uneven general pattern displayed by geographical distributions is
still very much the same as it was at the beginning of the XXth century, even
if the densities are higher -- another illustration of the well-known
socio-economic effect of self-reinforcement. Other geographical peculiarities
(local concentrations, national cultures and policies, electronic astronomy,
..) are discussed in the paper, as well as the uneasy separation between
amateur and professional astronomers in associations.
  Some events had a clear impact on the rate of foundation of astronomy-related
organizations, such as World Wars I and II, the beginning of space exploration,
the landing of man on the Moon, the end of the Cold War, spectacular comets,
and so on. However, as detailed in the paper, not all of them affected in the
same way Western Europe and North America, nor the various types of
organizations.
  The size of the vast majority of astronomy-related organizations is
relatively small, with again some differences between Western Europe and North
America.

</DOC>
<DOC>
<DOCNO> 8410 </DOCNO>
One-Dimensional Stochastic L\'evy-Lorentz Gas


  We introduce a L\'evy-Lorentz gas in which a light particle is scattered by
static point scatterers arranged on a line. We investigate the case where the
intervals between scatterers $\{\xi_i \}$ are independent random variables
identically distributed according to the probability density function $\mu(\xi
)\sim \xi^{-(1 + \gamma)}$. We show that under certain conditions the mean
square displacement of the particle obeys $<x^2 (t) > \ge C t^{3 - \gamma}$ for
$1 < \gamma < 2$. This behavior is compatible with a renewal L\'evy walk
scheme. We discuss the importance of rare events in the proper characterization
of the diffusion process.

</DOC>
<DOC>
<DOCNO> 70548 </DOCNO>
Radion Dynamics and Electroweak Physics


  The dynamics of a stabilized radion in the Randall-Sundrum model (RS) with
two branes is investigated, and the effects of the radion on electroweak
precision observables are evaluated. The radius is assumed to be stabilized
using a bulk scalar field as suggested by Goldberger and Wise. First the mass
and the wavefunction of the radion is determined including the backreaction of
the bulk stabilization field on the metric, giving a typical radion mass of
order the weak scale. This is demonstrated by a perturbative computation of the
radion wavefunction. A consequence of the background configuration for the
scalar field is that after including the backreaction the Kaluza-Klein (KK)
states of the bulk scalars couple directly to the Standard Model fields on the
TeV brane. Some cosmological implications are discussed, and in particular it
is found that the shift in the radion at late times is in agreement with the
four-dimensional effective theory result. The effect of the radion on the
oblique parameters is evaluated using an effective theory approach. In the
absence of a curvature-scalar Higgs mixing operator, these corrections are
small and give a negative contribution to S. In the presence of such a mixing
operator, however, the corrections can be sizable due to the modified Higgs and
radion couplings.

</DOC>
<DOC>
<DOCNO> 99933 </DOCNO>
Lifschitz tail in a magnetic field: coexistence of classical and quantum


  We establish the exact low-energy asymptotics of the integrated density of
states (Lifschitz tail) in a homogeneous magnetic field and Poissonian
impurities with a repulsive single-site potential of Gaussian decay. It has
been known that the Gaussian potential tail discriminates between the so-called
"classical" and "quantum" regimes, and precise asymptotics are known in these
cases. For the borderline case, the coexistence of the classical and quantum
regimes was conjectured. Here we settle this last remaining open case to
complete the full picture of the magnetic Lifschitz tails.

</DOC>
<DOC>
<DOCNO> 119107 </DOCNO>
Disks and Planets in Binary Systems


  The star formation process in molecular clouds usually leads to the formation
of multiple stellar systems, mostly binaries. Remaining disks around those
stars may be located around individual stars (circumstellar disks) or around
the entire binary system (circumbinary disk). We shall briefly review the
present observational evidence for both types of disks in binary stars, in
particular the properties of circumbinary disks.
  We then present recent results of the theoretical modeling of the collapse
and fragmentation of gravitationally unstable molecular cloud cores and their
implications for binary and disk formation, and discuss the dynamical influence
of the binary companions on disk truncation and gap formation. The presence of
binaries may have profound influence on the process of planet formation as
well. We present results on the stability and evolution of orbits of planets in
disks around binaries.

</DOC>
<DOC>
<DOCNO> 12036 </DOCNO>
Electronic transport in strongly anisotropic disordered systems: model


  We study numerically an electronic transport in strongly anisotropic weakly
disorderd two-dimensional systems. We find that the conductance distribution is
gaussian but the conductance fluctuations increase when anisotropy becomes
stronger. We interpret this result by random matrix theory with non-integer
symmetry parameter beta, in accordance with recent theoretical work of
K.A.Muttalib and J.R.Klauder [Phys.Rev.Lett. 82 (1999) 4272]. Analysis of the
statistics of transport paramateres supports this hypothesis.

</DOC>
<DOC>
<DOCNO> 102481 </DOCNO>
Metrics on the Real Quantum Plane


  Using the frame formalism we consider some possible metrics on the real
quantum plane. We require that the metric be real and symmetric. In practice
this means that we use the freedom of noncommutative geometry to impose a
different `sigma-symmetry', which is chosen so that a complex metric is
`sigma-real' and an un-symmetric metric is `sigma-symmetric'. The notion of
reality and symmetry are changed so that the definition of hermitian does not
change. An analysis is then made of a set of possible metrics.

</DOC>
<DOC>
<DOCNO> 120163 </DOCNO>
Is the Galactic center populated with young star clusters?


  We study the evolution and observability of young and compact star clusters
near the Galactic center, such as the Arches cluster and the Quintuplet. The
star clusters are modeled with a combination of techniques; using direct
N-body, integration to calculate the motions of all stars and detailed stellar
and binary evolution to follow the evolution of the stars. The modeled star
clusters dissolve within 10 to 60 million years in the tidal field of the
Galaxy. The projected stellar density in the modeled clusters drops within 5%
to 70% of the lifetime to a level comparable to the projected background
density towards the Galactic center. And it will be very hard to distinguished
these clusters at later age among the background stars. This effect is more
severe for clusters at larger distance from the Galactic center but in
projection at the same distance. Based on these arguments we conclude that the
Galactic center easily hides 10 to 40 clusters with characteristics similar to
the Arches and the Quintuplet cluster.

</DOC>
<DOC>
<DOCNO> 13836 </DOCNO>
Spin chains from super-models


  We construct and study a class of N particle supersymmetric Hamiltonians with
nearest and next-nearest neighbor inverse-square interaction in one dimension.
We show that inhomogeneous XY models in an external non-uniform magnetic field
can be obtained from these super-Hamiltonians in a particular limit decoupling
the fermionic degrees of freedom from the kinematic ones. We further consider a
suitable deformation of these super-models such that inhomogeneous XXZ
Hamiltonians in an external non-uniform magnetic field are obtained in the same
limit. We show that this deformed Hamiltonian with rational potential is, (i)
mapped to a set of free super-oscillators through a similarity transformation
and (ii) supersymmetric in terms of a new, non-standard realization of the
supercharge. We construct many exact eigenstates of this Hamiltonian and
discuss about the applicability of this technique to other models.

</DOC>
<DOC>
<DOCNO> 39634 </DOCNO>
High Rate Neutrino Detectors for Neutrino Factories


  Three types of high rate neutrino detectors for neutrino interaction physics
at neutrino factories are discussed. High performance general-purpose detectors
might collect event samples on the order of a billion events or more. This
could greatly improve on existing analyses of neutrino interactions and also
lead to new and important analysis topics including, for example, precise
determinations of the CKM matrix elements |Vub| and |Vcb|. The potential of
such general purpose detectors is illustrated with reference to a detector,
presented previously in reference hep-ex/9907033, that is structured around a
novel and compact vertexing and tracking neutrino target comprising a stack of
CCD pixel devices. Design ideas and prospects are also discussed for two types
of specialized detectors: (i) polarized targets filled with polarized solid
protium-deuterium (HD), for unique and powerful studies of the nucleon's spin
structure, and (ii) Fully active liquid tracking targets with masses of several
tonnes for precise determinations of the weak mixing angle, from the total
cross-section for neutrino-electron scattering. All three detector types pose
severe technical challenges but their utilization could add significantly to
the physics motivation for neutrino factories.

</DOC>
<DOC>
<DOCNO> 101138 </DOCNO>
Discrete singular convolution and its application to computational


  A new computational algorithm, the discrete singular convolution (DSC), is
introduced for computational electromagnetics. The basic philosophy behind the
DSC algorithm for the approximation of functions and their derivatives is
studied. Approximations to the delta distribution are constructed as either
bandlimited reproducing kernels or approximate reproducing kernels. A
systematic procedure is proposed to handle a number of boundary conditions
which occur in practical applications. The unified features of the DSC
algorithm for solving differential equations are explored from the point of
view of the method of weighted residuals. It is demonstrated that different
methods of implementation for the present algorithm, such as global, local,
Galerkin, collocation, and finite difference, can be deduced from a single
starting point. Both the computational bandwidth and the accuracy of the DSC
algorithm are shown to be controllable. Three example problems are employed to
illustrate the usefulness, test the accuracy and explore the limitation of the
DSC algorithm. A Galerkin-induced collocation approach is used for a waveguide
analysis in both regular and irregular domains and for electrostatic field
estimation via potential functions. Electromagnetic wave propagation in three
spatial dimensions is integrated by using a generalized finite difference
approach, which becomes a global-finite difference scheme at certain limit of
DSC parameters. Numerical experiments indicate that the proposed algorithm is a
promising approach for solving problems in electromagnetics.

</DOC>
<DOC>
<DOCNO> 13156 </DOCNO>
Stress Relaxation of Near-Critical Gels


  The time-dependent stress relaxation for a Rouse model of a crosslinked
polymer melt is completely determined by the spectrum of eigenvalues of the
connectivity matrix. The latter has been computed analytically for a mean-field
distribution of crosslinks. It shows a Lifshitz tail for small eigenvalues and
all concentrations below the percolation threshold, giving rise to a stretched
exponential decay of the stress relaxation function in the sol phase. At the
critical point the density of states is finite for small eigenvalues, resulting
in a logarithmic divergence of the viscosity and an algebraic decay of the
stress relaxation function. Numerical diagonalization of the connectivity
matrix supports the analytical findings and has furthermore been applied to
cluster statistics corresponding to random bond percolation in two and three
dimensions.

</DOC>
<DOC>
<DOCNO> 80624 </DOCNO>
Chiral gauged fermions on a lattice


  The chiral fermion model with local multifermion interactions proposed in
Nucl. Phys. B486 (1997) 282 and Phys. Rev. D61 (2000) 054502 processes an exact
SU_L(2) chiral gauge symmetry and SU_L(2) by U_R(1) chiral flavour symmetry on
a lattice and a plausible scaling region for the target chiral gauge theory in
the continuum limit. Following the previous analysis of massive and massless
fermion spectra in the scaling region, we compute the coupling vertices between
gauge field and fermions by the strong multifermion coupling expansion and
analytical continuation of these vertex functions in the energy-momentum space.
We show a peculiar scenario that a massless fermion is SU_L(2)-chirally gauged
in the low energy and 15 non-degenerate massive Dirac fermions are
SU_L(2)-vectorially gauged at the lattice scale O(1/a). The Ward identities
associated to the chiral gauge symmetry are realized by both the massless
chiral fermion and massive Dirac fermions. These Ward identities protect the
perturbative calculations in the small gauge coupling from hard gauge-symmetry
breakings and lead to the normal gauge-invariant renormalization prescription.
The vacuum functional is perturbatively computed by a continuum regularization
scheme in 16 edges of Brillouin zones. We achieve the correct form of the gauge
anomaly and U_L(1) fermion-flavour singlet anomaly with the soft chiral
symmetry breaking scale that is much smaller than the lattice scale. The
residual breakings of chiral gauge symmetry after the gauge anomaly
cancellation are eliminated in the normal gauge-invarinant renormalization
prescription. We discuss the consistency of the scenario and the reasons for it
to work for perturbative and non-perturbative gauge field.

</DOC>
<DOC>
<DOCNO> 10529 </DOCNO>
Long-range antiferromagnetic order in the S=1 chain compound LiVGe2O6


  The phase transition in the compound LiVGe2O6 has been proposed as a unique
example of a spin-Peierls transition in an S=1 antiferromagnetic chain. We
report neutron and x-ray diffraction measurements of LiVGe2O6 above and below
the phase transition at T=24 K. No evidence is seen for any structural
distortion associated with the transition. The neutron results indicate that
the low temperature state is antiferromagnetic, driven by ferromagnetic
interchain couplings.

</DOC>
<DOC>
<DOCNO> 99526 </DOCNO>
Verlinde bundles and generalized theta linear series


  In this paper we approach the study of generalized theta linear series on
moduli of vector bundles on curves via vector bundle techniques on abelian
varieties. We study what are called the Verlinde bundles in order to obtain
information about duality between theta functions and effective global and
normal generation on these moduli spaces.

</DOC>
<DOC>
<DOCNO> 12561 </DOCNO>
Static critical behavior of the ferromagnetic transition in LaMnO3.14


  The ferromagnetic phase transition in LaMnO3.14 is investigated by measuring
the dc magnetization as a function of magnetic field and temperature. Modified
Arrott plot and Kouvel Fisher analysis yield estimates for the critical
exponents beta, and gama, with values between that predicted for the Heisenberg
model and mean field theory. At low fields we found an anomalous small value of
beta, indicating that the critical behavior is influenced by the range of
magnetic fields used.

</DOC>
<DOC>
<DOCNO> 120989 </DOCNO>
The impact of chemical evolution on the observable properties of stellar


  The major effects of the chemical evolution of galaxies on the
characteristics of their stellar populations are reviewed. A few examples of
how the observed stellar properties derived from colour--magnitude diagrams can
constrain chemical evolution models are given.

</DOC>
<DOC>
<DOCNO> 11978 </DOCNO>
Electronic Entanglement in the Vicinity of a Superconductor


  A weakly biased normal-metal-superconductor junction is considered as a
potential device injecting entangled pairs of quasi-particles into a
normal-metal lead. The two-particle states arise from Cooper pairs decaying
into the normal lead and are characterized by entangled spin- and orbital
degrees of freedom. The separation of the entangled quasi-particles is achieved
with a fork geometry and normal leads containing spin- or energy-selective
filters. Measuring the current-current cross-correlator between the two normal
leads allows to probe the efficiency of the entanglement.

</DOC>
<DOC>
<DOCNO> 121741 </DOCNO>
A simple algorithm for orbit classification


  We describe a simple algorithm for classifying orbits into orbit families.
This algorithm works by finding patterns in the sign changes of the principal
coordinates. Orbits in the logarithmic potential are studied as an application;
we classify orbits into boxlet families, and examine the influence of the core
radius on the set of stable orbit families.

</DOC>
<DOC>
<DOCNO> 13068 </DOCNO>
Non-uniform ground state for the Bose gas


  We study the ground state, sum a_X |X>, of N hard-core bosons on a finite
lattice in configuration space, X={x_1,...,x_N}. All a_X being positive, the
ratios a_X / sum a_Y can be interpreted as probabilities P_a (X). Let E denote
the energy of the ground state and B_X the number of nearest-neighbor
particle-hole pairs in the configuration X. We prove the concentration of P_a
to X's with B_X in a sqrt(|E|)-neighborhood of |E|, show that the average of
a_X over configurations with B_X=n increases exponentially with n, discuss
fluctuations about this average, derive upper and lower bounds on E and give an
argument for off-diagonal long-range order in the ground state.

</DOC>
<DOC>
<DOCNO> 69313 </DOCNO>
Prompt J/psi Polarization at the Tevatron


  The polarization of prompt J/psi at the Tevatron is calculated within the
nonrelativistic QCD (NRQCD) factorization framework. The contribution from
radiative decays of P-wave charmonium states decreases, but does not eliminate,
the transverse polarization at large transverse momentum. The prediction agrees
with measurements from the CDF collaboration at intermediate values of p_T, but
disagrees at the large values of p_T measured.

</DOC>
<DOC>
<DOCNO> 170192 </DOCNO>
Quantum Algorithms for Element Distinctness


  We present several applications of quantum amplitude amplification to finding
claws and collisions in ordered or unordered functions. Our algorithms
generalize those of Brassard, Hoyer, and Tapp, and imply an O(N^{3/4} log N)
quantum upper bound for the element distinctness problem in the comparison
complexity model (contrasting with Theta(N log N) classical complexity). We
also prove a lower bound of Omega(N^{1/2}) comparisons for this problem and
derive bounds for a number of related problems.

</DOC>
<DOC>
<DOCNO> 40642 </DOCNO>
A Study of the Decay D0->K+pi-


  Using a large sample of photoproduced charm mesons from the FOCUS experiment
at Fermilab (FNAL-E831), we observe the decay $D^0\to K^+\pi^-$ with a signal
yield of $149\pm31$ events compared to a similarly cut sample consisting of
$36760 \pm 195$ $D^0\to K^-\pi^+$ events. We use the observed ratio of $D^0\to
K^+\pi^-$ to $D^0\to K^-\pi^+$ $(0.404\pm 0.085\pm 0.025)%$ to obtain a
relationship between the $D^0$ mixing and doubly Cabibbo suppressed decay
parameters.

</DOC>
<DOC>
<DOCNO> 120358 </DOCNO>
Chandra imaging of the complex X-ray core of the Perseus cluster


  We report subarcsec-resolution X-ray imaging of the core of the Perseus
cluster around the galaxy NGC 1275 with the Chandra X-ray Observatory. The
ROSAT-discovered holes associated with the radio lobes have X-ray bright rims
which are cooler than the surrounding gas and not due to shocks. The holes
themselves may contain some hotter gas. We map strong photoelectric absorption
across the Northern lobe and rim due to a small infalling irregular galaxy,
known as the high velocity system. Two outer holes, one of which was previously
known, are identified with recently found spurs of low-frequency radio
emission. The spiral appearance of the X-ray cooler gas and the outer optical
parts of NGC 1275 may be due to angular momentum in the cooling flow.

</DOC>
<DOC>
<DOCNO> 69070 </DOCNO>
On Realistic Brane Worlds from Type I Strings


  We review recent progress in constructing realistic brane models from type I
string vacua. Explicit models with three families of the standard model gauge
group and its left-right generalizations are presented with supersymmetry
broken at the string scale of order $M_s\sim 10^{10-12}$ GeV, realizing gravity
mediated supersymmetry breaking at low energies. Unification of couplings
occurs at the string scale due to the particular U(1) normalizations of
D-branes, as well as to the existence of a Higgs field per family of quarks and
leptons. The proton is naturally stable due to intrinsic discrete symmetries of
the corresponding string theory. In particular R-parity appears as a natural
stringy symmetry. There are axionic fields with the right couplings as to solve
the strong CP problem. Similar realizations are also presented for a string
scale of 1 TeV, although without solving the gauge unification problem. Open
questions are briefly discussed.

</DOC>
<DOC>
<DOCNO> 72066 </DOCNO>
High $p_T$ Azimuthal Asymmetry in Non-central A+A at RHIC


  The high $p_{\rm T}>3$ GeV azimuthal asymmetry, $v_2(p_{\rm T})$, in
non-central nuclear collisions at RHIC is shown to be a sensitive measure of
the initial parton density distribution of the produced quark-gluon plasma. A
generalization of the Gyulassy-Levai-Vitev (GLV) non-abelian energy loss
formalism including Bjorken 1+1D expansion as well as important kinematic
constraints is used.

</DOC>
<DOC>
<DOCNO> 100489 </DOCNO>
Th\'eor\`eme de Hartogs-Bochner dans $P_2(\mathbb{C})$


The present paper have been replaced by the paper: Hartogs-Bochner type
theorem in Projective Space (math.CV/0011095) in which we prove the following
Hartogs-Bochner type theorem: Let $M$ be a connected $C^2$ hypersurface of
$P_n(\mathbb{C})$ ($n\geq 2$) which divides $P_n(\mathbb{C})$ in two connected
open sets $\Omega_1$ and $\Omega_2$. Then there exists $i \in \{1,2\}$ such
that $C^{1}$ CR functions defined on $M$ extends holomorphically to
$\Omega_i$.

</DOC>
<DOC>
<DOCNO> 170257 </DOCNO>
Unpolarized light in quantum optics


  We present a new derivation of the unpolarized quantum states of light, whose
general form was first derived by Prakash and Chandra [Phys. Rev. A 4, 796
(1971)]. Our derivation makes use of some basic group theory, is
straightforward, and offers some new insights.

</DOC>
<DOC>
<DOCNO> 85321 </DOCNO>
Charged Rotating Black Holes in 5d Einstein-Maxwell-(A)dS Gravity


  We obtain charged rotating black hole solutions to the theory of
Einstein-Maxwell gravity with cosmological constant in five dimensions. Some of
the physical properties of these black holes are discussed.

</DOC>
<DOC>
<DOCNO> 9968 </DOCNO>
Spectral Properties of the k-Body Embedded Gaussian Random Ensembles


  See cond-mat/0010425 and cond-mat/0010426.

</DOC>
<DOC>
<DOCNO> 120050 </DOCNO>
BeppoSAX spectroscopy of the NGC7078 (M15) globular cluster X-ray source


  Results of a 1999 November 16--17 BeppoSAX observation of the low-mass X-ray
binary X2127+119 located in the globular cluster NGC7078 are presented. The
system is believed to be one where the central neutron star is normally
obscured by the accretion disk, and only X-rays scattered into our line of
sight by an extended accretion disk corona (ADC) are observed. The 0.1--10 keV
lightcurve is energy dependent and shows two partial eclipses separated by the
17.1 hr orbital period. The 0.1--100 keV spectrum is unusually complex, but can
be successfully modeled using a partially covered power-law and disk-blackbody
model. Together with a column consistent with the interstellar value to
NGC7078, about 60% of the source is covered by an additional column of 1E22
atom/cm2. The absorbed component may be X-rays that pass through the outer
layers of the accretion disk. The energy dependent intensity variations by a
factor of ~2 may be modeled as due to a changing normalization of the
disk-blackbody. None of the other spectral parameters appear to clearly depend
on luminosity. The same spectral model is also able to fit an archival ASCA
spectrum.

</DOC>
<DOC>
<DOCNO> 121800 </DOCNO>
Evolution and Nucleosynthesis of Very Massive Primordial Stars


  We investigate the evolution, final fate, and nucleosynthetic yields of
rotating and non-rotating very massive stars (VMS) of zero metallicity. First
we address the issue of mass loss during hydrogen burning due to vibrational
instabilities. We find that these objects are much more stable than what was
found in previous studies of VMS of solar composition, and expect only
negligible mass loss driven by the pulsations. As these stars thus reach the
end of their evolution with massive helium cores, they encounter the
pair-creation instability. We find that for helium core masses of ~64...133
solar masses these stars are completely disrupted with explosion energies of up
to ~1E53 erg and eject up to ~60 solar masses of Ni56 Stars with more massive
helium cores collapse into black holes. We present the first calculations that
follow the collapse of such a massive rotating star and predict that X-ray
burst and significant gravitational wave emission could result.

</DOC>
<DOC>
<DOCNO> 10303 </DOCNO>
Small polaron formation in dangling-bond wires on the Si(001) surface


  From electronic structure calculations, we find that carriers injected into
dangling-bond atomic wires on the Si(001) surface will self-trap to form
localised polaron states. The self-trapping distortion takes the form of a
local suppression of the buckling of the dimers in the wire, and is
qualitatively different for the electron and hole polarons. This result points
to the importance of polaronic effects in understanding electronic motion in
such nanostructures.

</DOC>
<DOC>
<DOCNO> 102236 </DOCNO>
Rinehart complexes and Batalin-Vilkovisky algebras


  For a Lie-Rinehart algebra (A,L) such that, as an A-module, L is finitely
generated and projective of finite constant rank, the relationship between
generators of the Gerstenhaber bracket and connections on the highest
A-exterior power of L given in an earlier paper arises from the canonical
pairing between the exterior A-powers of L. Thus, given an exact generator for
the corresponding Gerstenhaber algebra, the chain complex underlying the
resulting Batalin-Vilkovisky algebra coincides with the Rinehart complex
computing the corresponding Lie-Rinehart homology.

</DOC>
<DOC>
<DOCNO> 85181 </DOCNO>
On gyroscopic precession


  The vorticity of a congruence is often considered to be the rate of rotation
for the precession of a gyroscope moving along a world-line belonging to that
congruence. Our aim here was to determine the evolution equation for the
angular momentum of a gyrosocope with respect to an arbitrary time-like
congruence: i.e, a reference congruence not containing the curve described by
the gyroscope. In particular, we show the specific conditions needed to support
the introductory statement about the vorticity. We thus establish a
well-founded theoretical description for the analysis of the precession of
gyroscopes, providing suitable conclusions for possible experiments.

</DOC>
<DOC>
<DOCNO> 70840 </DOCNO>
Exact Chiral Symmetry with a non-perturbative cutoff


  The main ideas behind the new ways to preserve chiral symmetries for lattice
fermions are presented. The discussion is focused on vector-like fermions, the
case relevant for lattice QCD.

</DOC>
<DOC>
<DOCNO> 102462 </DOCNO>
On the asymptotic linking number


  We prove a theorem formulated by V. I. Arnold concerning a relation between
the asymptotic linking number and the Hopf invariant of divergence-free vector
fields. Using a modified definition for the system of short paths, we prove
their existence in the general case.

</DOC>
<DOC>
<DOCNO> 13731 </DOCNO>
Kinetic roughening model with opposite Kardar-Parisi-Zhang


  We introduce a model that simulates a kinetic roughening process with two
kinds of particles: one follows the ballistic deposition (BD) kinetic and, the
other, the restricted solid-on-solid (KK) kinetic. Both of these kinetics are
in the universality class of the nonlinear KPZ equation, but the BD kinetic has
a positive nonlinear constant while the KK kinetic has a negative one. In our
model, called BD-KK model, we assign the probabilities p and (1-p) to the KK
and BD kinetics, respectively. For a specific value of p, the system behaves as
a quasi linear model and the up-down symmetry is recuperated. We show that
nonlinearities of odd-order are relevant in these low nonlinear limit.

</DOC>
<DOC>
<DOCNO> 178815 </DOCNO>
Structure of the exotic nucleus $^{14}$B in the ground state


  We investigate the structure of the neutron rich nucleus $^{14}$B through
studies of its breakup in the Coulomb field of a heavy target. The breakup
amplitude is calculated within an adiabatic as well as finite range DWBA
theories of breakup reactions. Both these formalisms allow the use of realistic
wave functions for the relative motion between the fragments in the ground
state of the projectile. The longitudinal momentum distributions of $^{13}$B
(ground state) following the breakup of $^{14}$B on a heavy target at beam
energy of 60 MeV/nucleon, calculated using two possible ground state
configurations of $^{14}$B, have been compared with the recent data. The data
seem to favour $^{13}$B(${3\over 2}^-)\otimes2s_{1/2}$ as the possible ground
state configuration of $^{14}$B with a spectroscopic factor close to unity. We
give our predictions for the neutron angular distributions and the relative
energy spectra in the one-neutron removal reaction of $^{14}$B.

</DOC>
<DOC>
<DOCNO> 13243 </DOCNO>
Meissner effect in a bosonic ladder


  We investigate the effect of a magnetic field on a bosonic ladder. We show
that such a system leads to the one dimensional equivalent of a vortex lattice
in a superconductor. We investigate the physical properties of the vortex
phase, such as vortex density and vortex correlation functions and show that
magnetization has plateaus for some commensurate values of the mag netic field.
The lowest plateau corresponds to a true Meissner to vortex transition at a
critical field $H_{c1}$ that exists although the system has no long range
superconducting order. Implications for experimental realizations such as
Josephson junction arrays are discussed.

</DOC>
<DOC>
<DOCNO> 11797 </DOCNO>
Simulation of Stochastic Volatility using Path Integration: Smiles and


  We apply path integration techniques to obtain option pricing with stochastic
volatility using a generalized Black-Scholes equation known as the Merton and
Garman equation. We numerically simulate the option prices using the technique
of path integration. Using market data, we determine the parameters of the
model. It is found that the market chooses a special class of models for which
a more efficient algorithm, called the bisection method, is applicable. Using
our simulated data, we generate some implied volatility curves. We also analyze
and study in detail some of the characteristics of the volatility curves within
the model.

</DOC>
<DOC>
<DOCNO> 170550 </DOCNO>
Quantum coherence and control in one- and two-photon optical systems


  We investigate coherence in one- and two-photon optical systems, both
theoretically and experimentally. In the first case, we develop the density
operator representing a single photon state subjected to a non-dissipative
coupling between observed (polarization) and unobserved (frequency) degrees of
freedom. We show that an implementation of ``bang-bang'' quantum control
protects photon polarization information from certain types of decoherence. In
the second case, we investigate the existence of a "decoherence-free" subspace
of the Hilbert space of two-photon polarization states under the action of a
similar coupling. The density operator representation is developed analytically
and solutions are obtained numerically.
  NOTE: This manuscript is taken from the author's undergraduate thesis (A.B.
Dartmouth College, June 2000, advised by Dr. Walter E. Lawrence), under the
supervision of Dr. Paul G. Kwiat.

</DOC>
<DOC>
<DOCNO> 121426 </DOCNO>
Radio continuum emission from M31 and M33


  The radio emission from M31 (like HI, CO, FIR and H\alpha) is concentrated in
the '10 kpc ring', giving an impressive example that cosmic rays are produced
in star-forming regions. M31 and M33 have similar strengths of the total
magnetic field, but very different field structures: The field structure in M31
is exceptionally regular while that in M33 is rather irregular compared with
other spiral galaxies. In M33 the polarized intensity is highest between the
spiral arms, similar to most spiral galaxies, while in M31 total and polarized
emission both emerge from the ring. Star formation in M31 is probably too weak
to tangle the regular field. The high regularity of the field in the M31 ring
allows fast cosmic-ray propagation. As a consequence, there is no equipartition
between the energy densities of cosmic rays and total magnetic fields. Faraday
rotation measures show that the regular field in the ring is uni-directional,
signature of the basic axisymmetric dynamo mode with a pitch angle of only -12
degr. Faraday rotation of polarized background sources shows that the regular
field and thermal gas in M31 extend to at least 25 kpc radius. The regular
field in M33 forms an open spiral, a mixture of axisymmetric and higher modes,
with the largest pitch angle (\simeq 60 degr) observed in any spiral galaxy so
far. Vertical filaments in the NW and SE indicate interaction between the thin
and the thick disk of M31. The total emission in the central region of M31
follows the spiral and radial H\alpha filaments, while the polarized emission
is strongest on the inner edge of the southern spiral filament.

</DOC>
<DOC>
<DOCNO> 101396 </DOCNO>
Invariant differential operators on nonreductive homogeneous spaces


  A systematic exposition is given of the theory of invariant differential
operators on a not necessarily reductive homogeneous space. This exposition is
modelled on Helgason's treatment of the general reductive case and the special
non-reductive case of the space of horocycles. As a final application the
differential operators on (not a priori reductive) isotropic pseudo-Riemannian
spaces are characterized.

</DOC>
<DOC>
<DOCNO> 120406 </DOCNO>
A CCD Study of the Environment of Seyfert Galaxies: III. Host Galaxies


  A technique is described that permits the robust decomposition of the bulge
and disk components of a sample of Seyfert galaxies, as well as a (control)
sample of non-active galaxies matched to the Seyferts in the distributions of
redshift, luminosity and morphological classification. The structural
parameters of the host galaxies in both samples are measured. No statistically
significant differences at greater than the 95% level are found in these
parameters according to a K-S test.
  ``Companion galaxies'' --- defined as any galaxy within a projected
separation of 200 h^{-1} kpc from the center of the host --- are identified and
their basic properties measured. A comparison between the active and control
samples in the distributions of apparent R magnitude, absolute R magnitude
(assuming the ``companions'' are at the distance of the host), projected
separation from the host, position angle relative to the host, magnitude
difference between the companion and host, and strength of the tidal parameter,
show no statistically significant differences.
  Similarly, no statistically significant differences are found between the
control and active sample host galaxies in terms of light asymmetries --- bars,
rings, isophotal twisting, etc. The implications for a model in which
interactions and mergers are responsible for inciting activity in galactic
nuclei are discussed briefly.

</DOC>
<DOC>
<DOCNO> 72090 </DOCNO>
Violation of Equivalence Principle and Solar Neutrinos


  We have updated the analysis for the solution to the solar neutrino problem
by the long-wavelength neutrino oscillations induced by a tiny breakdown of the
weak equivalence principle of general relativity, and obtained a very good fit
to all the solar neutrino data.

</DOC>
<DOC>
<DOCNO> 10453 </DOCNO>
Spectral Statistics of the Two-Body Random Ensemble Revisited


  Using longer spectra we re-analyze spectral properties of the two-body random
ensemble studied thirty years ago. At the center of the spectra the old results
are largely confirmed, and we show that the non-ergodicity is essentially due
to the variance of the lowest moments of the spectra. The longer spectra allow
to test and reach the limits of validity of French's correction for the number
variance. At the edge of the spectra we discuss the problems of unfolding in
more detail. With a Gaussian unfolding of each spectrum the nearest neighbour
spacing distribution between ground state and first exited state is shown to be
stable. Using such an unfolding the distribution tends toward a semi-Poisson
distribution for longer spectra. For comparison with the nuclear table ensemble
we could use such unfolding obtaining similar results as in the early papers,
but an ensemble with realistic splitting gives reasonable results if we just
normalize the spacings in accordance with the procedure used for the data.

</DOC>
<DOC>
<DOCNO> 9734 </DOCNO>
Spin Effects in the Local Density of States of GaAs


  We present spin-resolved measurements of the local density of states in Si
doped GaAs. Both spin components exhibit strong mesoscopic fluctuations. In the
magnetic quantum limit, the main features of the spin-up and spin-down
components of the local density of states are found to be identical apart from
Zeeman splitting. Based on this observation, we introduce a mesoscopic method
to measure the $g$-factor in a material where macroscopic methods are severely
restricted by disorder. Differences between the spin-up and spin-down
components are discussed in terms of spin relaxation due to spin-orbit
coupling.

</DOC>
<DOC>
<DOCNO> 39643 </DOCNO>
ICANOE - Imaging and Calorimetric Neutrino Oscillation Experiment


  The main scientific goal of the ICANOE detector is the one of elucidating in
a comprehensive way the pattern of neutrino masses and mixings, following the
SuperKamiokande results and the observed solar neutrinos deficit. To achieve
these goals, the experimental method is based upon the complementary and
simultaneous detection of CERN beam (CNGS) and cosmic ray (CR) events. For the
currently allowed values of the SuperKamiokande results, both CNGS and cosmic
ray data will give independent measurements and provide a precise determination
of the oscillation parameters.

</DOC>
<DOC>
<DOCNO> 69300 </DOCNO>
The Genesis of Cosmological Tracker Fields


  The role of the quintessence field as a probable candidate for the repulsive
dark energy, the conditions for tracking and the requisites for tracker fields
are examined. The concept of `integrated tracking' is introduced and a new
criterion for the existence of tracker potentials is derived assuming monotonic
increase in the scalar energy density parameter \Omega_\phi with the evolution
of the universe as suggested by the astrophysical constraints. It provides a
technique to investigate generic potentials of the tracker fields. The general
properties of the tracker fields are discussed and their behaviour with respect
to tracking parameter \epsilon is analyzed. It is shown that the tracker fields
around the limiting value \epsilon \simeq \frac 23 give the best fit with the
observational constraints.

</DOC>
<DOC>
<DOCNO> 68313 </DOCNO>
Vacuum Polarisation Tensors in Constant Electromagnetic Fields: Part II


  In the second part of this series we apply the ``string-inspired'' technique
to the calculation of one-loop amplitudes involving both vectors and
axialvectors, as well as a general constant electromagnetic background field.
The vector-axialvector two-point function in a constant field is calculated
explicitly.

</DOC>
<DOC>
<DOCNO> 68224 </DOCNO>
Localised Gravity in the Singular Domain Wall Background?


  We study singular, supersymmetric domain-wall solutions supported by the
massive breathing mode scalars of, for example, sphere reductions in M-theory
or string theory. The space-time on one side of such a wall is asymptotic to
the Cauchy horizon of the anti-de Sitter (AdS) space-time. However, on the
other side there is a naked singularity. The higher-dimensional embedding of
these solutions has the novel interpretation of (sphere compactified) brane
configurations in the domain ``inside the horizon region,'' with the
singularity corresponding to the sphere shrinking to zero volume. The naked
singularity is the source of an infinite attractive gravitational potential for
the fluctuating modes. Nevertheless, the spectrum is bounded from below,
continuous and positive definite, with the wave functions suppressed in the
region close to the singularity. The massless bound state is formally excluded
due to the boundary condition for the fluctuating mode wave functions at the
naked singularity. However, a regularisation of the naked singularity, for
example by effects of the order of the inverse string scale, in turn
regularises the gravitational potential and allows for precisely one (massless)
bound-state spin-2 fluctuating mode. We also contrast spectra in these domain
wall backgrounds with those of the domain walls due to the massless modes of
sphere reductions.

</DOC>
<DOC>
<DOCNO> 151587 </DOCNO>
On Anthropic Solutions of the Cosmological Constant Problem


  Motivated by recent work of Bousso and Polchinski (BP), we study theories
which explain the small value of the cosmological constant using the anthropic
principle. We argue that simultaneous solution of the gauge hierarchy problem
is a strong constraint on any such theory. We exhibit three classes of models
which satisfy these constraints. The first is a version of the BP model with
precisely two large dimensions. The second involves 6-branes and antibranes
wrapped on supersymmetric 3-cycles of Calabi-Yau manifolds, and the third is a
version of the irrational axion model. All of them have possible problems in
explaining the size of microwave background fluctuations. We also find that
most models of this type predict that all constants in the low energy
Lagrangian, as well as the gauge groups and representation content, are chosen
from an ensemble and cannot be uniquely determined from the fundamental theory.
In our opinion, this significantly reduces the appeal of this kind of solution
of the cosmological constant problem. On the other hand, we argue that the
vacuum selection problem of string theory might plausibly have an anthropic,
cosmological solution.

</DOC>
<DOC>
<DOCNO> 101842 </DOCNO>
Symmetries of Gromov-Witten invariants


  The group (Z/nZ)^2 is shown to act on the Gromov-Witten invariants of the
complex flag manifold. We also deduce several corollaries of this result.

</DOC>
<DOC>
<DOCNO> 150904 </DOCNO>
D3-brane Holography


  It has recently been conjectured that the AdS_5/SYM_4 correspondence can be
generalized away from the conformal limit, to a duality between supergravity on
the full asymptotically flat three-brane background and a theory characterized
as N=4 SYM deformed in the IR by a specific dimension-eight operator. Assuming
that this relation is valid, we derive a prescription for computing n-point
correlation functions in the holographic theory, which reduces to the standard
AdS/CFT recipe at low energies. One- and two-point functions are discussed in
detail. The prescription follows from very simple considerations and appears to
be applicable to any asymptotically flat background. We also compute the
quark-antiquark potential and comment on the description of the baryon in the
supergravity picture. We conclude with some comments on the possible relation
between our work and recent results in non-commutative field theories.

</DOC>
<DOC>
<DOCNO> 13442 </DOCNO>
Excitonic emission in the presence of a two dimensional electron gas: a


  The near- and far-field photoluminescence spectra of a gated two-dimensional
electron gas have been measured. Spatial fluctuations in the electron density
are found to be manifested as spatial fluctuations in the emission amplitude of
the negatively charged exciton (X$^{-}$) and in the peak energy of the neutral
exciton (X). Consequently, the far-field X$^{-}$ spectrum is a homogoneously
broadened Lorentzian, while the X lineshape exhibits substantial inhomogenous
broadening. We present a novel and simple technique to extract the electron
density from the X$^{-}$ spectrum. We show that width of the far-field X line
is proportional to the electron density fluctuations; hence it can be used to
characterize the inhomogeneity in the electron density.

</DOC>
<DOC>
<DOCNO> 68251 </DOCNO>
FeynHiggsFast: a program for a fast calculation of masses and mixing


  FeynHiggsFast is a Fortran code for the calculation of the masses and the
mixing angle of the neutral CP-even Higgs bosons in the MSSM up to two-loop
order. It is based on a compact analytical approximation formula of the
complete diagrammatic one-loop and the dominant two-loop contributions. At the
one-loop level a leading logarithmic result is used, taking into account all
sectors of the MSSM. At the two-loop level at O(alpha alpha_s) the leading
logarithmic and non-logarithmic contributions are taken into account. The
approximation formula is valid for arbitrary choices of the parameters in the
Higgs sector of the model. Comparing its quality to the full diagrammatic
result, we find agreement better than 2 GeV for most parts of the MSSM
parameter space.

</DOC>
<DOC>
<DOCNO> 68091 </DOCNO>
Disentangling running coupling and conformal effects in QCD


  We investigate the relation between a postulated skeleton expansion and the
conformal limit of QCD. We begin by developing some consequences of an
Abelian-like skeleton expansion, which allows one to disentangle
running-coupling effects from the remaining skeleton coefficients. The latter
are by construction renormalon-free, and hence hopefully better behaved. We
consider a simple ansatz for the expansion, where an observable is written as a
sum of integrals over the running-coupling. We show that in this framework one
can set a unique Brodsky-Lepage-Mackenzie (BLM) scale-setting procedure as an
approximation to the running-coupling integrals, where the BLM coefficients
coincide with the skeleton ones. Alternatively, the running-coupling integrals
can be approximated using the effective charge method. We discuss the
limitations in disentangling running coupling effects in the absence of a
diagrammatic construction of the skeleton expansion. Independently of the
assumed skeleton structure we show that BLM coefficients coincide with the
conformal coefficients defined in the small $\beta_0$ (Banks-Zaks) limit where
a perturbative infrared fixed-point is present. This interpretation of the BLM
coefficients should explain their previously observed simplicity and smallness.
Numerical examples are critically discussed.

</DOC>
<DOC>
<DOCNO> 69832 </DOCNO>
Parton Distributions in the Virtual Photon Target and Factorization


  We investigate parton distributions in the virtual photon target, both
polarized and unpolarized, up to the next-leading order (NLO) in QCD. Parton
distributions can be predicted completely up to NLO, but they are
factorization-scheme-dependent. We analyze parton distributions in several
factorization schemes and discuss their scheme dependence. Particular
attentions are paid to the axial anomaly effect on the first moments of the
polarized quark parton distributions, and also to the large-$x$ behaviors of
polarized and unpolarized parton distributions.

</DOC>
<DOC>
<DOCNO> 119386 </DOCNO>
FUSE Observations of Diffuse Interstellar Molecular Hydrogen


  We describe a moderate-resolution FUSE mini-survey of H2 in the Milky Way and
Magellanic Clouds, using four hot stars and four AGN as background sources.
FUSE spectra of nearly every stellar and extragalactic source exhibit numerous
absorption lines from the H2 Lyman and Werner bands between 912 and 1120 A. One
extragalactic sightline, PKS 2155-304, with low N(HI) shows no detectable H2
and could be the "Lockman Hole" of molecular gas, of importance for QSO
absorption-line studies. We measure H2 column densities in low rotational
states (J = 0 and 1) to derive rotational and/or kinetic temperatures of
diffuse interstellar gas. The higher-J abundances can constrain models of the
UV radiation fields and gas densities. In three optically thick clouds toward
extragalactic sources, we find n(H) ~ 30-50 cm(-3) and cloud thicknesses of 2-3
pc. The rotational temperatures for H2 at high Galactic latitude, <T_01> = 107
+/- 17 K (seven sightlines) and 120 +/- 13 K (three optically thick clouds),
are higher than those in the Copernicus sample composed primarily of targets in
the disk. We find no evidence for great differences in the abundance or state
of excitation of H2 between sight lines in the Galaxy and those in the SMC and
LMC. In the future, we will probe the distribution and physical parameters of
diffuse molecular gas in the disk and halo and in the lower-metallicity
environs of the LMC and SMC.

</DOC>
<DOC>
<DOCNO> 83092 </DOCNO>
An Usage Measure Based on Psychophysical Relations


  A new word usage measure is proposed. It is based on psychophysical relations
and allows to reveal words by its degree of "importance" for making basic
dictionaries of sublanguages.

</DOC>
<DOC>
<DOCNO> 119405 </DOCNO>
Comparison between Observed and Theoretical Red Giant Branch Luminosity


  V-band luminosity functions have been obtained for the upper main-sequence,
sub-giant branch and red giant branch of 18 galactic globular clusters from HST
data. A comparison with four sets of theoretical models has been performed. In
contrast with what was found in several previous works, a Good general
agreement has been found between the observed and theoretical LF at any
metallicity [M/H]<-0.7. Possible discrepancies at higher metallicity, in the
upper part of the RGB, need to be confirmed with further observational data and
by extending all the models to the most metal rich regime. The SGB shape has
been used to set an upper limit to the cluster age, and consequently a lower
limit on the cluster distance. A discussion on the still open problem of the
mismatch between the observed and theoretical RGB bump location is also
presented.

</DOC>
<DOC>
<DOCNO> 119446 </DOCNO>
Dynamical processes, element mixing and chemodynamical cycles in dwarf


  Since the chemical evolution of galaxies seems to differ between
morphological types and deviates in many details from the standard scenario the
question has to be addressed when, how and to what amount metal-enriched ejecta
from Supernovae and Planetary Nebulae polute their environment. Since recent
observations of dwarf galaxies show no significant metal abundance gradients
throughout the galaxies while enhancement of metals happens in isolated HII
regions, an effective mixing process has to be assumed. Chemodynamical
evolution models can provide a possible explanation by demonstrating that
strong evaporation of gas clouds by hot gas and following condensation leads to
an almost perfect mixing of the gas. We focus on the different phases of
chemodynamical evolution that are experienced by a representative dwarf
irregular galaxy model and present a quantitative analysis of the
chemodynamical gas flow cycles.

</DOC>
<DOC>
<DOCNO> 71913 </DOCNO>
Lensing at cosmological scales: a test of higher dimensional gravity


  Recent developments in gravitational lensing astronomy have paved the way to
genuine mappings of the gravitational potential at cosmological scales. We
stress that comparing these data with traditional large scale structure surveys
will provide us with a test of gravity at such scales. These constraints could
be of great importance in the framework of higher dimensional cosmological
models.

</DOC>
<DOC>
<DOCNO> 68306 </DOCNO>
Axial anomaly, vector meson dominance and $\pi^0 \to \gamma \gamma$ at


  A thermal Finite Energy QCD Sum Rule is used to determine the temperature
behaviour of the $\omega \rho \pi$ strong coupling. This coupling decreases
with increasing $T$ and vanishes at the critical temperature, a likely signal
for quark deconfinement. This is then used in the Vector Meson Dominance (VMD)
expression for the $\pi^0 \to \gamma \gamma$ amplitude, which is also found to
vanish at the critical temperature, as expected. This result supports the
validity of VMD at $T \neq 0$. However, if VMD would not hold at finite
temperature, then there is no prediction for the $\pi^0 \to \gamma \gamma$
amplitude.

</DOC>
<DOC>
<DOCNO> 8359 </DOCNO>
A microscopic approach to phase transitions in quantum systems


  We present a new theoretical approach for the study of the phase diagram of
interacting quantum particles: bosons, fermions or spins. In the neighborhood
of a phase transition, the expected renormalization group structure is
recovered both near the upper and lower critical dimension. Information on the
microscopic hamiltonian is also retained and no mapping to effective field
theories is needed. A simple approximation to our formally exact equations is
studied for the spin-$S$ Heisenberg model in three dimensions where explicit
results for critical exponents, critical temperature and coexistence curve are
obtained.

</DOC>
<DOC>
<DOCNO> 102345 </DOCNO>
A symplectic proof of Seiberg-Witten blow-up formula


  In this paper, we give a symplectic proof for Seiberg-Witten blow-up formula
of four dimensional symplectic manifolds, especially we interpret a strange
phenomenon that the genera of embedding J-holomorphic curves will decrease when
we symplectically blow-up the four dimensional symplectic manifold.

</DOC>
<DOC>
<DOCNO> 120312 </DOCNO>
The X-ray Faint Early-Type Galaxy NGC4697


  We analyze archival ROSAT HRI, ROSAT PSPC, and ASCA data of the X-ray faint
early-type galaxy NGC4697. The joint ROSAT PSPC + ASCA spectrum is fit by a
two-component thermal model, a MEKAL model with kT_{MEKAL}=0.26^{+0.04}_{-0.03}
keV with low metallicity and a bremsstrahlung model with
kT_{BREM}=5.2^{+3.0}_{-1.6} keV. A similar model was found to fit the spectra
of another faint early-type galaxy (NGC4382) and the bulge of M31. We interpret
this soft emission as a combination of emission from a soft component of low
mass X-ray binaries (LMXBs) and from a low temperature interstellar medium,
although the relative contributions of the two components could not be
determined. Twelve point sources were identified within 4' of NGC4697, of which
11 are most likely LMXBs associated with the galaxy. The soft X-ray colors of
four of the LMXBs in NGC4697 support the claim that LMXBs possess a soft
spectral component. Finally, we present a simulation of what we believe the
Chandra data of NGC4697 will look like.

</DOC>
<DOC>
<DOCNO> 13361 </DOCNO>
Spinon Attraction in Spin-1/2 Antiferromagnetic Chains


  We derive the representation of the two-spinon wavefunction for the
Haldane-Shastry model in terms of the spinon coordinates. This result allows us
to rigorously analyze spinon interaction and its physical effects. We show that
spinons attract one another. The attraction gets stronger as the size of the
system is increased and, in the thermodynamic limit, determines the power law
with which the susceptibility diverges.

</DOC>
<DOC>
<DOCNO> 102127 </DOCNO>
Elliptic functions and equations of modular curves


  Let $p\ge 5$ be a prime. We show that the space of weight one Eisenstein
series defines an embedding into $\PP^{(p-3)/2}$ of the modular curve $X_1(p)$
for the congruence group $\Gamma_1(p)$ that is scheme-theoretically cut out by
explicit quadratic equations.

</DOC>
<DOC>
<DOCNO> 84613 </DOCNO>
Exact Inflationary Solutions from a Superpotential


  We propose a novel, potentially useful generating technique for constructing
exact solutions of inflationary scalar field cosmologies with non-trivial
potentials. The generating scheme uses the so-called superpotential and is
inspired by recent studies of similar equations in supergravity. Some exact
solutions are derived, and the physical meaning of the superpotential in these
models is clarified.

</DOC>
<DOC>
<DOCNO> 9482 </DOCNO>
Inquiries into the Nature of Free Energy and Entropy in Respect to


  Free energy and entropy are examined in detail from the standpoint of
classical thermodynamics. The approach is logically based on the fact that
thermodynamic work is mediated by thermal energy through the tendency for
nonthermal energy to convert spontaneously into thermal energy and for thermal
energy to distribute spontaneously and uniformly within the accessible space.
The fact that free energy is a Second-Law, expendable energy that makes it
possible for thermodynamic work to be done at finite rates is emphasized.
Entropy, as originally defined, is pointed out to be the capacity factor for
thermal energy that is hidden with respect to temperature; it serves to
evaluate the practical quality of thermal energy and to account for changes in
the amounts of latent thermal energies in systems maintained at constant
temperature. A major objective was to clarify the means by which free energy is
transferred and conserved in sequences of biological reactions coupled by
freely diffusible intermediates. In achieving this objective it was found
necessary to distinguish between a 'characteristic free energy' possessed by
all First-Law energies in amounts equivalent to the amounts of the energies
themselves and a 'free energy of concentration' that is intrinsically
mechanical and relatively elusive in that it can appear to be free of First-Law
energy. The findings in this regard serve to clarify the fact that the transfer
of chemical potential energy from one repository to another along sequences of
biological reactions of the above sort occurs through transfer of the First-Law
energy as thermal energy and transfer of the Second-Law energy as free energy
of concentration.

</DOC>
<DOC>
<DOCNO> 170724 </DOCNO>
A Neutral Atom and a Charged Wire: From Elastic scattering to Absorption


  We solve the problem of a neutral atom interacting with a charged wire,
giving rise to an attractive 1/r^2 potential in two dimensions. We show how a
suitable average over all possible self-adjoint extensions of the radial
Schroedinger Hamiltonian eventually leads to the classical formula for
absorption of the atom, a formula shown to be in agreement with a recent
experiment.

</DOC>
<DOC>
<DOCNO> 123028 </DOCNO>
Investigating ULIRGs in the Near-Infrared: Imaging & Spectroscopy


  We present imaging and spectroscopic observations of 2 nearby (z<0.1) ULIRGs
from a larger sample, and address the question of whether the JHK continuum
colours and slope might be effective probes of the nuclear region in searches
for AGN. Certainly there is evidence for significant quantities of hot dust
emission at temperatures >1000K; but it may be that rather than pointing to an
AGN, this instead tells us more about the environment and evolution of the star
formation.

</DOC>
<DOC>
<DOCNO> 13661 </DOCNO>
Magnetic Anisotropy of a Single Cobalt Nanoparticle


  Using a new microSQUID set-up, we investigate magnetic anisotropy in a single
1000-atoms cobalt cluster. This system opens new fields in the characterization
and the understanding of the origin of magnetic anisotropy in such
nanoparticles. For this purpose, we report three-dimensional switching field
measurements performed on a 3 nm cobalt cluster embedded in a niobium matrix.
We are able to separate the different magnetic anisotropy contributions and
evidence the dominating role of the cluster surface.

</DOC>
<DOC>
<DOCNO> 67909 </DOCNO>
The four-fermi coupling of the supersymmetric non-linear sigma-model on


  The reducible K\"ahler coset space G/S\otimesU(1)^k is discussed in a
geometrical approach. We derive the formula which expresses the Riemann
curvature of the reducible K\"ahler coset space in terms of its Killing
vectors. The formula manifests the group structure of G. On the basis of this
formula we establish an algebraic method to evaluate the four-fermi coupling of
the supersymmetric non-linear sigma-model on G/S\otimesU(1)^k at the low-energy
limit. As an application we consider the supersymmetric non-linear sigma-model
on E_7/SU(5)\otimesU(1)^3 which contains the three families of {10} + {5^*} +
{1} of SU(5) as the pseudo NG fermions. The four-fermi coupling constants among
diffferent families of the fermions are explicitly given at the low-energy
limit.

</DOC>
<DOC>
<DOCNO> 100196 </DOCNO>
Torsion Elements in the Mapping Class Group of a Surface


  Given a finite set of $r$ points in a closed surface of genus $g$, we
consider the torsion elements in the mapping class group of the surface leaving
the finite set invariant. We show that the torsion elements generate the
mapping class group if and only if $(g, r) \neq (2, 5k+4)$ for some integer
$k$.

</DOC>
<DOC>
<DOCNO> 13595 </DOCNO>
Persistence of a Continuous Stochastic Process with Discrete-Time


  We introduce the concept of `discrete-time persistence', which deals with
zero-crossings of a continuous stochastic process, X(T), measured at discrete
times, T = n \Delta T. For a Gaussian Markov process with relaxation rate \mu,
we show that the persistence (no crossing) probability decays as \rho(a)^n for
large n, where a = \exp(-\mu \Delta T), and we compute \rho(a) to high
precision. We also define the concept of `alternating persistence', which
corresponds to a<0. For a>1, corresponding to motion in an unstable potential
(\mu<0), there is a nonzero probability of having no zero-crossings in infinite
time, and we show how to calculate it.

</DOC>
<DOC>
<DOCNO> 117503 </DOCNO>
X-ray sources as tracers of the large-scale structure in the Universe


  We review the current status of studies of large-scale structure in the X-ray
Universe. After motivating the use X-rays for cosmological purposes, we discuss
the various approaches used on different angular scales including X-ray
background multipoles, cross-correlations of the X-ray background with galaxy
catalogues, clustering of X-ray selected sources and small-scale fluctuations
and anisotropies in the X-ray background. We discuss the implications of the
above studies for the bias parameter of X-ray sources, which is likely to be
moderate for X-ray selected AGN and the X-ray background (~1-2). We finally
outline how all-sky X-ray maps at hard X-rays and medium surveys with large sky
coverage could provide important tests for the cosmological models.

</DOC>
<DOC>
<DOCNO> 7876 </DOCNO>
Fermi surface origin of the interrelationship between magnetocrystalline


  Recently, we outlined a scheme to investigate the effects of compositional
order on the magnetocrystalline anisotropy of alloys from a first-principles
electronic structure point of view \{Phys. Rev. Lett. {\bf 83}, 5369 (1999)\}
and showed that compositional order enhances the magnitude of
magnetocrystalline anisotropy energy (MAE) of Co$_{0.5}$Pt$_{0.5}$ alloy by
some two orders of magnitude as well as affecting the equilibrium magnetization
direction. Here we describe our scheme in detail and present an in-depth study
of the effect by demonstrating its Fermi surface origin. In
Co$_{0.25}$Pt$_{0.75}$ alloy we find that the perfect $ L1_2 $ structure has a
very small MAE whereas imposition of directional order enhances the MAE by two
orders of magnitude. We also present the effect of lattice distortion
(tetragonalization) on the MAE on the same footing and find that in the
Co$_{0.5}$Pt$_{0.5}$ alloy it accounts for only about 20% of the observed MAE,
thus confirming that compositional order is the major player in the enhancement
of MAE. We also examine the directional chemical order that can be produced by
magnetic annealing within the same framework. We extract a Fermi surface
mechanism for the effect in an explicit study of permalloy. Finally, we propose
that the Fermi surface plays a major role in the strong coupling between
magnetocrystalline anisotropy and compositional order in many magnetic alloys.

</DOC>
<DOC>
<DOCNO> 71265 </DOCNO>
Thermalisation of inhomogeneous quantum scalar fields in 1+1D


  Using an improved version of the Hartree approximation, allowing for
ensembles of inhomogeneous configurations, we show in a $\lambda \phi^4$
theory, that initially the system thermalises with a Bose-Einstein
distribution. For later times and larger couplings we see deviations.

</DOC>
<DOC>
<DOCNO> 99451 </DOCNO>
Extremal metrics on graphs I


  We define a number of natural (from geometric and combinatorial points of
view) deformation spaces of valuations on finite graphs, and study functions
over these deformation spaces. These functions include both direct metric
invariants (girth, diameter), and spectral invariants (the determinant of the
Laplace operator, or complexity; bottom non-zero eigenvalue of the Laplace
operator). We show that almost all of these functions are, surprisingly,
convex, and we characterize the valuations extremizing these invariant

</DOC>
<DOC>
<DOCNO> 12791 </DOCNO>
Interface localisation-delocalisation transition in a symmetric polymer


  Using extensive Monte Carlo simulations we study the phase diagram of a
symmetric binary (AB) polymer blend confined into a thin film as a function of
the film thickness D. The monomer-wall interactions are short ranged and
antisymmetric, i.e, the left wall attracts the A-component of the mixture with
the same strength as the right wall the B-component, and give rise to a first
order wetting transition in a semi-infinite geometry. The phase diagram and the
crossover between different critical behaviors is explored. For large film
thicknesses we find a first order interface localisation/delocalisation
transition and the phase diagram comprises two critical points, which are the
finite film width analogies of the prewetting critical point. Using finite size
scaling techniques we locate these critical points and present evidence of 2D
Ising critical behavior. When we reduce the film width the two critical points
approach the symmetry axis $\phi=1/2$ of the phase diagram and for $D \approx 2
R_g$ we encounter a tricritical point. For even smaller film thickness the
interface localisation/delocalisation transition is second order and we find a
single critical point at $\phi=1/2$.
  Measuring the probability distribution of the interface position we determine
the effective interaction between the wall and the interface. This effective
interface potential depends on the lateral system size even away from the
critical points. Its system size dependence stems from the large but finite
correlation length of capillary waves. This finding gives direct evidence for a
renormalization of the interface potential by capillary waves in the framework
of a microscopic model.

</DOC>
<DOC>
<DOCNO> 13710 </DOCNO>
NMR and NQR Fluctuation Effects in Layered Superconductors


  We study the effect of thermal fluctuations of the s-wave order parameter of
a quasi two dimensional superconductor on the nuclear spin relaxation rate near
the transition temperature Tc. We consider both the effects of the amplitude
fluctuations and the Berezinskii-Kosterlitz-Thouless (BKT) phase fluctuations
in weakly coupled layered superconductors. In the treatment of the amplitude
fluctuations we employ the Gaussian approximation and evaluate the longitudinal
relaxation rate 1/T1 for a clean s-wave superconductor, with and without pair
breaking effects, using the static pair fluctuation propagator D. The increase
in 1/T1 due to pair breaking in D is overcompensated by the decrease arising
from the single particle Green's functions. The result is a strong effect on
1/T1 for even a small amount of pair breaking. The phase fluctuations are
described in terms of dynamical BKT excitations in the form of pancake
vortex-antivortex (VA) pairs. We calculate the effect of the magnetic field
fluctuations caused by the translational motion of VA excitations on 1/T1 and
on the transverse relaxation rate 1/T2 on both sides of the BKT transitation
temperature T(BKT)<Tc. The results for the NQR relaxation rates depend strongly
on the diffusion constant that governs the motion of free and bound vortices as
well as the annihilation of VA pairs. We discuss the relaxation rates for real
multilayer systems where the diffusion constant can be small and thus increase
the lifetime of a VA pair, leading to an enhancement of the rates. We also
discuss in some detail the experimental feasibility of observing the effects of
amplitude fluctuations in layered s-wave superconductors such as the
dichalcogenides and the effects of phase fluctuations in s- or d-wave
superconductors such as the layered cuprates.

</DOC>
<DOC>
<DOCNO> 8062 </DOCNO>
Universal c-axis conductivity of high-$T_c$ oxides in the


  The anisotropy in the temperature dependence of the in-plane and c-axis
conductivities of high-T_c cuprates in the superconducting state is shown to be
consistent with a strong in-plane momentum dependence of both the quasiparticle
scattering rate and the interlayer hopping integral. Applying the cold spot
scattering model recently proposed by Ioffe and Millis (Phys. Rev. B {\bf 58},
11631 (1998)) to the superconducting state, we find that the c-axis
conductivity varies approximately as T^3 in an intermediate temperature regime,
in good agreement with the experimental result for optimally doped
YBa_2Cu_3O_{7-x} and Bi_2Sr_2CaCu_2O_{8+x}.

</DOC>
<DOC>
<DOCNO> 67682 </DOCNO>
Geometrodynamics of Variable-Speed-of-Light Cosmologies


  This paper is dedicated to the memory of Dennis Sciama.
  Variable-Speed-of-Light (VSL) cosmologies are currently attracting interest
as an alternative to inflation. We investigate the fundamental geometrodynamic
aspects of VSL cosmologies and provide several implementations which do not
explicitly break Lorentz invariance (no "hard" breaking). These "soft"
implementations of Lorentz symmetry breaking provide particularly clean answers
to the question "VSL with respect to what?". The class of VSL cosmologies we
consider are compatible with both classical Einstein gravity and low-energy
particle physics. These models solve the "kinematic" puzzles of cosmology as
well as inflation does, but cannot by themselves solve the flatness problem,
since in their purest form no violation of the strong energy condition occurs.
We also consider a heterotic model (VSL plus inflation) which provides a number
of observational implications for the low-redshift universe if chi contributes
to the "dark energy" either as CDM or quintessence. These implications include
modified gravitational lensing, birefringence, variation of fundamental
constants and rotation of the plane of polarization of light from distant
sources.

</DOC>
<DOC>
<DOCNO> 71112 </DOCNO>
Covariant nucleon electromagnetic form factors from the


  We present a study of proton and neutron electromagnetic form factors for the
recently proposed Goldstone-boson-exchange constituent quark model. Results for
charge radii, magnetic moments, and electric as well as magnetic form factors
are reported. The calculations are performed in a covariant framework using the
point-form approach to relativistic quantum mechanics. All the predictions by
the Goldstone-boson-exchange constituent quark model are found in remarkably
good agreement with existing experimental data.

</DOC>
<DOC>
<DOCNO> 84628 </DOCNO>
Axiomatic approach to radiation reaction of scalar point particles in


  Several different methods have recently been proposed for calculating the
motion of a point particle coupled to a linearized gravitational field on a
curved background. These proposals are motivated by the hope that the point
particle system will accurately model certain astrophysical systems which are
promising candidates for observation by the new generation of gravitational
wave detectors. Because of its mathematical simplicity, the analogous system
consisting of a point particle coupled to a scalar field provides a useful
context in which to investigate these proposed methods. In this paper, we
generalize the axiomatic approach of Quinn and Wald in order to produce a
general expression for the self force on a point particle coupled to a scalar
field following an arbitrary trajectory on a curved background. Our equation
includes the leading order effects of the particle's own fields, commonly
referred to as ``self force'' or ``radiation reaction'' effects. We then
explore the equations of motion which follow from this expression in the
absence of non-scalar forces.

</DOC>
<DOC>
<DOCNO> 101315 </DOCNO>
A survey of Wall's finiteness obstruction


  Wall's finiteness obstruction is an algebraic K-theory invariant which
decides if a finitely dominated space is homotopy equivalent to a finite CW
complex. The object of this survey is to describe the invariant (which was
first formulated in 1965) and some of its many applications to the surgery
classification of manifolds.

</DOC>
<DOC>
<DOCNO> 69216 </DOCNO>
Proton and neutron charge form factors in soliton model with


  Nucleon electromagnetic form factors are considered in the framework of the
generalized Skyrme model with dilaton-quarkonium field. In our recent
publication we have got big discrepancies between calculated form factors and
dipole approximation formula. Here we have reasonably good accordance between
them in finite impulse region after vector meson dominance have been taken into
account. Omega and Rho -meson have been included into only hadron structure of
the photon.

</DOC>
<DOC>
<DOCNO> 119925 </DOCNO>
Forming Clusters of Galaxies as the Origin of Unidentified GeV Gamma-Ray


  Over half of GeV gamma-ray sources observed by the EGRET experiment have not
yet been identified as known astronomical objects. There is an isotropic
component of such unidentified sources, whose number is about 60 in the whole
sky. Here we calculate the expected number of dynamically forming clusters of
galaxies emitting gamma-rays by high energy electrons accelerated in the shock
wave when they form, in the framework of the standard theory of structure
formation. We find that a few tens of such forming clusters should be
detectable by EGRET and hence a considerable fraction of the isotropic
unidentified sources can be accounted for, if about 5% of the shock energy is
going into electron acceleration. We argue that these clusters are very
difficult to detect in x-ray or optical surveys compared with the conventional
clusters, because of their extended angular size of about 1 degree. Hence they
define a new population of ``gamma-ray clusters''. If this hypothesis is true,
the next generation gamma-ray telescopes such as GLAST will detect more than a
few thousands of gamma-ray clusters. It would provide a new tracer of
dynamically evolving structures in the universe, in contrast to the x-ray
clusters as a tracer of hydrodynamically stabilized systems. We also derive the
strength of magnetic field required for the extragalactic gamma-ray background
by structure formation to extend up to 100 GeV as observed, that is about
10^{-5} of the shock-heated baryon energy density.

</DOC>
<DOC>
<DOCNO> 8988 </DOCNO>
Flexible Linear Polyelectrolytes in Multivalent Salt Solutions:


  Polyelectrolytes such as single and double stranded DNA and many synthetic
polymers undergo two structural transitions upon increasing the concentration
of multivalent salt or molecules. First, the expanded-stretched chains in low
monovalent salt solutions collapse into nearly neutral compact structures when
the density of multivalent salt approaches that of the monomers. With further
addition of multivalent salt the chains redissolve acquiring expanded-coiled
conformations. We study the redissolution transition using a two state model
[F. Solis and M. Olvera de la Cruz, {\it J. Chem. Phys.} {\bf 112} (2000)
2030]. The redissolution occurs when there is a high degree of screening of the
electrostatic interactions between monomers, thus reducing the energy of the
expanded state. The transition is determined by the chemical potential of the
multivalent ions in the solution $\mu$ and the inverse screening length
$\kappa$. The transition point also depends on the charge distribution along
the chain but is almost independent of the molecular weight and degree of
flexibility of the polyelectrolytes. We generate a diagram of $\mu$ versus
$\kappa^2$ where we find two regions of expanded conformations, one with
charged chains and other with overcharged (inverted charge) chains, separated
by a collapsed nearly neutral conformation region. The collapse and
redissolution transitions occur when the trajectory of the properties of the
salt crosses the boundaries between these regions. We find that in most cases
the redissolution occurs within the same expanded branch from which the chain
precipitates.

</DOC>
<DOC>
<DOCNO> 10898 </DOCNO>
Anomalous Behavior of the Contact Process with Aging


  The effect of power-law aging on a contact process is studied by simulation
and using a mean-field approach. We find that the system may approach its
stationary state in a nontrivial, nonmonotonous way. For the particular value
of the aging exponent, $\alpha=1$, we observe a rich set of behaviors:
depending on the process parameters, the relaxation to the stationary state
proceeds as $1/\ln t$ or via a power law with a nonuniversal exponent.
Simulation results suggest that for $0<\alpha<1$, the absorbing-state phase
transition is in the universality class of directed percolation.

</DOC>
<DOC>
<DOCNO> 117178 </DOCNO>
A Plasma Model for RF Breakdown in Accelerator Structures


  A plasma model is presented for the formation of ``cathode spots'' and
subsequent crater development near field emission sites on a copper surface in
the presence of a strong dc electric field. Adding to previously published
models, we propose that the two-stream plasma instability relates the plasma
density to its dimensions. Arguments are presented that suggest that the
formation and dynamics of such plasma spots are essentially the same phenomenon
for both dc and rf fields. A consequence for accelerating structures is that,
when such plasma spots are present, they erode the copper surface at a rate on
the order of 300 micrograms per Coulomb of ion bombardment current. This
erosion rate can have a measurable effect on the rf properties of an
accelerating structure after processing at high gradients for a few hundred
hours.

</DOC>
<DOC>
<DOCNO> 150382 </DOCNO>
T-duality of non-commutative gauge theories


  Via T-duality a theory of open strings on a D1-brane wrapped along a cycle of
slanted torus is described by a U(1) gauge theory on a D2-brane in the B-field
background. It is also known that there is another dual description of the
D1-brane configuration by a non-commutative gauge theory on a D2-brane.
Therefore, these two gauge theories on D2-branes are equivalent. Recently, the
existence of a continuous set of equivalent gauge theories including these two
was suggested. We give a dual D1-brane configuration for each theory in this
set, and show that the relation among parameters for equivalent gauge theories
can be easily reproduced by rotation of the D1-brane configuration. We also
discuss a relation between this duality and Morita equivalence.

</DOC>
<DOC>
<DOCNO> 150631 </DOCNO>
Diverse PBGS Patterns and Superbranes


  This is a brief account of the approach to superbranes based upon the concept
of Partial Breaking of Global Supersymmetry (PBGS).

</DOC>
<DOC>
<DOCNO> 121031 </DOCNO>
Chemical Evolution of Galaxies


  Chemical evolution of galaxies brings together ideas on stellar evolution and
nucleosynthesis with theories of galaxy formation, star formation and galaxy
evolution, with all their associated uncertainties. In a new perspective
brought about by the Hubble Deep Field and follow-up investigations of global
star formation rates, diffuse background etc., it has become necessary to
consider the chemical composition of dark baryonic matter as well as that of
visible matter in galaxies.

</DOC>
<DOC>
<DOCNO> 150755 </DOCNO>
A note on gravity-scalar fluctuations in holographic RG flow geometries


  We study five-dimensional gravity models with non-vanishing background scalar
fields which are dual to non-conformal boundary field theories. We develop a
procedure to decouple the graviton fluctuations from the scalar ones and apply
it to the simplest case of one scalar field. The quadratic action for the
decoupled scalar fluctuations has a very simple form and can be used to compute
two-point functions. We perform this computation for the two examples of
background RG flow recently considered by DeWolfe and Freedman and find
physically reasonable results.

</DOC>
<DOC>
<DOCNO> 118874 </DOCNO>
The Redshift Distribution of FIRST Radio Sources at 1 mJy


  We present spectra for a sample of radio sources from the FIRST survey, and
use them to define the form of the redshift distribution of radio sources at
mJy levels.We targeted 365 sources and obtained 46 redshifts (13 per cent of
the sample). We find that our sample is complete in redshift measurement to R
$\sim 18.6$, corresponding to $z\sim 0.2$. Early-type galaxies represent the
largest subset (45 per cent) of the sample and have redshifts $0.15\la z \la
0.5$ ; late-type galaxies make up 15 per cent of the sample and have redshifts
$0.05\la z \la 0.2$; starbursting galaxies are a small fraction ($\sim 6$ per
cent), and are very nearby ($z\la 0.05$). Some 9 per cent of the population
have Seyfert1/quasar-type spectra, all at $z\ga 0.8$, and there are 4 per cent
are Seyfert2 type galaxies at intermediate redshifts ($z\sim 0.2$). Using our
measurements and data from the Phoenix survey, we obtain an estimate for $N(z)$
at $S_{1.4 \rm {GHz}}\ge 1$ mJy and compare this with model predictions. At
variance with previous conclusions, we find that the population of starbursting
objects makes up $\la 5 $ per cent of the radio population at S $\sim 1$ mJy.

</DOC>
<DOC>
<DOCNO> 9640 </DOCNO>
Ga NMR study of the local susceptibility in SrCr8Ga4O19: pseudogap and


  We present the first Ga(4f) NMR study of the Cr susceptibility in the
archetype of Kagome based frustrated antiferromagnets,
SrCr$_{8}$Ga$_{4}$O$_{19}$. Our major finding is that the susceptibility of the
frustrated lattice goes through a maximum around 50 K. Our data also supports
the existence of paramagnetic ``clusters'' of spins, responsible for the Curie
behavior observed in the macroscopic susceptibility at low T. These results set
novel features for the constantly debated physics of geometrically frustrated
magnets.

</DOC>
<DOC>
<DOCNO> 85564 </DOCNO>
Vacuum Polarization in the Spacetime of a Scalar-Tensor Cosmic String


  We study the vacuum polarization effect in the spacetime generated by a
magnetic flux cosmic string in the framework of a scalar-tensor gravity. The
vacuum expectation values of the energy-momentum tensor of a conformally
coupled scalar field are calculated. The dilaton's contribution to the vacuum
polarization effect is shown explicitly.

</DOC>
<DOC>
<DOCNO> 9232 </DOCNO>
Zero-temperature equation of state of quasi-one dimensional H2


  We have studied molecular hydrogen in a pure 1D geometry and inside a narrow
carbon nanotube by means of the diffusion Monte Carlo method. The
one-dimensionality of H2 in the nanotube is well maintained in a large density
range, this system being closer to an ideal 1D fluid than liquid 4He in the
same setup. H2 shares with 4He the existence of a stable liquid phase and a
quasi-continuous liquid-solid transition at very high linear densities.

</DOC>
<DOC>
<DOCNO> 151894 </DOCNO>
Comments on the Riemann conjecture and index theory on Cantorian fractal


  An heuristic proof of the Riemman conjecture is proposed. It is based on the
old idea of Polya-Hilbert. A discrete/fractal derivative self adjoint operator
whose spectrum may contain the nontrivial zeroes of the zeta function is
presented. To substantiate this heuristic proposal we show using generalized
index-theory arguments, corresponding to the (fractal) spectral dimensions of
fractal branes living in Cantorian-fractal space-time, how the required
$negative$ traces associated with those derivative operators naturally agree
with the zeta function evaluated at the spectral dimensions. The $\zeta (0) = -
1/2$ plays a fundamental role. Final remarks on the recent developments in the
proof of the Riemann conjecture are made.

</DOC>
<DOC>
<DOCNO> 80962 </DOCNO>
High Temperature Limit of the $ N= 2 $ IIA Matrix Model


  The high temperature limit of a system of two D-0 branes is investigated. The
partition function can be expressed as a power series in $\beta$ (inverse
temperature). The leading term in the high temperature expression of the
partition function and effective potential is calculated {\em exactly}.
Physical quantities like the mean square separation can also be exactly
determined in the high temperature limit. We comment on SU(3) IIB matrix model
and the difficulties to study it.

</DOC>
<DOC>
<DOCNO> 9584 </DOCNO>
Thermodynamic Properties of the Two-Dimensional Two-Component Plasma


  The model under consideration is a two-dimensional two-component plasma,
stable against collapse for the dimensionless coupling constant $\beta<2$. The
combination of a technique of renormalized Mayer expansion with the mapping
onto the sine-Gordon theory provides the full thermodynamics of the plasma in
the whole stability range of $\beta$. The explicit forms of the
density-fugacity relationship and of the specific heat (at constant volume) per
particle are presented.

</DOC>
<DOC>
<DOCNO> 150934 </DOCNO>
Two-Black-Hole Bound States


  The quantum mechanics of $N$ slowly-moving BPS black holes in five dimensions
is considered. A divergent continuum of states describing arbitrarily closely
bound black holes with arbitrarily small excitation energies is found. A
superconformal structure appears at low energies and can be used to define an
index counting the weighted number of supersymmetric bound states. It is shown
that the index is determined from the dimensions of certain cohomology classes
on the symmetric product of $N$ copies of $R^4$. An explicit computation for
the case of N=2 with no angular momentum yields a finite nonzero result.

</DOC>
<DOC>
<DOCNO> 85208 </DOCNO>
Slowly Rotating General Relativistic Superfluid Neutron Stars


  We present a general formalism to treat slowly rotating general relativistic
superfluid neutron stars. As a first approximation, their matter content can be
described in terms of a two-fluid model, where one fluid is the neutron
superfluid, which is believed to exist in the core and inner crust of mature
neutron stars, and the other fluid represents a conglomerate of all other
constituents (crust nuclei, protons, electrons, etc.). We obtain a system of
equations, good to second-order in the rotational velocities, that determines
the metric and the matter variables, irrespective of the equation of state for
the two fluids. In particular, allowance is made for the so-called entrainment
effect, whereby the momentum of one constituent (e.g. the neutrons) carries
along part of the mass of the other constituent. As an illustration of the
developed framework, we consider a simplified equation of state for which the
two fluids are described by different polytropes. We determine numerically the
effects of the two fluids on the rotational frame-dragging, the induced changes
in the neutron and proton densities and the inertial mass, as well as the
change in shape of the star. We further discuss issues regarding conservation
of the two baryon numbers, the mass-shedding (Kepler) limit and chemical
equilibrium.

</DOC>
<DOC>
<DOCNO> 85155 </DOCNO>
Scalar-tensor gravity in an accelerating universe


  We consider scalar-tensor theories of gravity in an accelerating universe.
The equations for the background evolution and the perturbations are given in
full generality for any parametrization of the Lagrangian, and we stress that
apparent singularities are sometimes artifacts of a pathological choice of
variables. Adopting a phenomenological viewpoint, i.e., from the observations
back to the theory, we show that the knowledge of the luminosity distance as a
function of redshift up to z ~ (1-2), which is expected in the near future,
severely constrains the viable subclasses of scalar-tensor theories. This is
due to the requirement of positive energy for both the graviton and the scalar
partner. Assuming a particular form for the Hubble diagram, consistent with
present experimental data, we reconstruct the microscopic Lagrangian for
various scalar-tensor models, and find that the most natural ones are obtained
if the universe is (marginally) closed.

</DOC>
<DOC>
<DOCNO> 71711 </DOCNO>
Searching Scalar Resonances with Ultra-high Energy Neutrinos


  We study the prospects of detecting signals of a resonant scattering of
high-energy cosmic neutrinos on electrons in the atmosphere. Such a process is
possible through an s-channel exchange of a isotriplet scalar particle
predicted by some particle physics theories. We estimate the event rates for a
reference detector setup with plausible assumptions on the interaction
strengths and energy resolutions. We find as the most promising process the
resonance production of tau neutrinos whose signature would be a "quiet" (in
contrast with a hadronic "bang") production of the tau lepton followed by a
more noisy decay in downstream.

</DOC>
<DOC>
<DOCNO> 72111 </DOCNO>
Universal Torsion Induced Interaction from Large Extra Dimensions


  We consider a model with extra compact dimensions in which only gravity
exists in the 4+n dimensional bulk. If the gravitational connection is not
assumed to be symmetric, that is, unless torsion is artificially set to zero,
then a universal contact interaction among the fermions on the 4-dimensional
wall is induced. Using a global fit to Z-pole observables, we find the 3 sigma
bound on the scale of quantum gravity to be M_S = 28 TeV for n=2. If Dirac or
light sterile neutrinos are present, the data from SN1987A increase the bound
to \sqrt{n} M_S >= 210 TeV.

</DOC>
<DOC>
<DOCNO> 170137 </DOCNO>
QED in dispersing and absorbing media


  After giving an outline of the quantization scheme based on the microscopic
Hopfield model of a dielectric bulk material, we show how the classical
phenomenological Maxwell equations of the electromagnetic field in the presence
of dielectric matter of given space- and frequency-dependent complex
permittivity can be transferred to quantum theory. Including in the theory the
interaction of the medium-assisted field with atomic systems, we present both
the minimal-coupling Hamiltonian and the multipolar-coupling Hamiltonian in the
Coulomb gauge. To illustrate the concept, we discuss the input--output
relations of radiation and the transformation of radiation-field quantum states
at absorbing four-port devices, and the spontaneous decay of an excited atom
near the surface of an absorbing body and in a spherical micro-cavity with
intrinsic material losses. Finally, we give an extension of the quantization
scheme to other media such as amplifying media, magnetic media, and nonlinear
media.

</DOC>
<DOC>
<DOCNO> 9046 </DOCNO>
Magnetic Properties of HTSC with a Weak Interlayer Coupling


  Magnetic properties of layered high temperature superconductors with a weak
interlayer coupling in the region of the critical fluctuations are investigated
in the framework of the Ginzburg--Landau approach. The sample magnetization is
calculated within a perturbative approach to the second order in the interlayer
coupling constant. The first order correction can be incorporated into the
non-interacting expression for the magnetization with the corresponding shift
of the critical temperature. Only the second order contribution modifies the
thermodynamics, leading to violation of the one-parameter 2D scaling low and to
disappearance of the magnetization crossing point.

</DOC>
<DOC>
<DOCNO> 152310 </DOCNO>
D-branes as Solitons of an N=1, D=10 Non-commutative Gauge Theory


  We consider a Dp brane within a D9 brane in the presence of a B-field whose
polarization is {\em transverse} to the Dp brane. To be definite, we take a
D3-D9 system. It is observed that the system has the same pattern of
supersymmetry breaking as that of a soliton of the six dimensional
non-commutative gauge theory that is obtained by dimensional reduction of an
{\cal N}=1, D=10 gauge theory. These results indicate that the soliton solution
is the low energy realization of a D3 brane in a D9 brane with a transverse
B-field, hence can be viewed as a generalization of the previous results in the
literature where similar observations were made for lower codimensional cases.

</DOC>
<DOC>
<DOCNO> 101928 </DOCNO>
On algebro-geometric Poisson brackets for the Volterra lattice


  A generalization of the theory of algebro-geometric Poisson brackets on the
space of finite-gap Schroedinger operators, developped by S. P. Novikov and A.
P. Veselov, to the case of periodic zero-diagonal difference operators of
second order is proposed. A necessary and sufficient condition for such a
bracket to be compatible with higher Volterra flows is found.

</DOC>
<DOC>
<DOCNO> 8132 </DOCNO>
Steady-state mode III cracks in a viscoelastic lattice model


  We extend the Slepyan solution of the problem of a steady-state crack in an
infinite ideally brittle lattice model to include dissipation in the form of
Kelvin viscosity. As a demonstration of this technique, based on the
Wiener-Hopf method, we apply the method to mode III cracks in a square lattice.
We use this solution to find the critical velocity at which the steady-state
solution becomes inconsistent due to additional bond-breaking; this point
signaling the onset of complex dynamical behavior.

</DOC>
<DOC>
<DOCNO> 71990 </DOCNO>
Supernova Neutrino Detection in Borexino


  We calculated the expected neutrino signal in Borexino from a typical Type II
supernova at a distance of 10 kpc. A burst of around 110 events would appear in
Borexino within a time interval of about 10 s. Most of these events would come
from the reaction channel $\bar{\nu}_e+p\to e^++n$, while about 30 events would
be induced by the interaction of the supernova neutrino flux on $^{12}$C in the
liquid scintillator. Borexino can clearly distinguish between the
neutral-current excitations $^{12}{C}(\nu,\nu')^{12}{C}^*$(15.11 MeV) and the
charged-current reactions $^{12}{C}(\nu_e,e^-)^{12}{N}$ and
$^{12}{C}(\bar{\nu}_e,e^+)^{12}{B}$, via their distinctive event signatures.
The ratio of the charged-current to neutral-current neutrino event rates and
their time profiles with respect to each other can provide a handle on
supernova and non-standard neutrino physics (mass and flavor oscillations).

</DOC>
<DOC>
<DOCNO> 70873 </DOCNO>
Asymmetry of p(->)+p(->)->gamma+jet+X process and problem of Delta G


  The gamma +jet production in p(->)-p(->) collisions at high energies is
studied. Double-spin asymmetry A{LL} of the process is calculated by using
Monte Carlo code SPHINX. The predictions for A{LL} of the gamma +jet production
in the p(->)-p(->) collisions using the spin-dependent gluon distributions with
positive and negative sign of $\Delta G(x,Q^2)$ are made at RHIC energies. A
possibility to extract the spin-dependent gluon distributions Delta G at STAR
experiment and to discriminate between different theoretical scenarios is
discussed.

</DOC>
<DOC>
<DOCNO> 80982 </DOCNO>
A consistency check for Renormalons in Lattice Gauge Theory: beta^(-10)


  We compute the perturbative expansion of the Lattice SU(3) plaquette to
beta^(-10) order. The result is found to be consistent both with the expected
renormalon behaviour and with finite size effects on top of that.

</DOC>
<DOC>
<DOCNO> 150945 </DOCNO>
Three Field Dynamics in (1+1)-dimensions


  In a model of nonlinear system of three scalar fields the problem on dynamics
of a massive particle moving in effective potential provided by two
relativistic fields is solving. The potentials for these fields are chosen in
the form of anti-Higgs and Higgs potentials. It is shown that the effective
potential has the shape of two-hump barrier localized in spacetime. It tends to
constant attractive potential at spacetime infinity. The magnitude of this
constant constituent is determined by the Higgs condensate. It is shown that
nonlinear equation of motion of a particle has the solutions which describe the
capture of a particle by the barrier and the scattering on the barrier.

</DOC>
<DOC>
<DOCNO> 12701 </DOCNO>
The Kohn mode for trapped Bose gases within the dielectric formalism


  The presence of undamped harmonic center of mass oscillations of a weakly
interacting Bose gas in a harmonic trap is demonstrated within the dielectric
formalism for a previously introduced finite temperature approximation
including exchange. The consistency of the approximation with the Kohn theorem
is thereby demonstrated. The Kohn modes are found explicitly, generalizing an
earlier zero-temperature result found in the literature. It is shown how the
Kohn mode disappears from the single-particle spectrum, while remaining in the
density oscillation spectrum, when the temperature increases from below to
above the condensation temperature.

</DOC>
<DOC>
<DOCNO> 14083 </DOCNO>
Modelling background charge rearrangements near single-electron


  Background charge rearrangements in metallic single-electron transistors are
modelled in two-level tunnelling systems as a Poisson process with a scale
parameter as only variable. The model explains the recent observation of
asymmetric Coulomb blockade peak spacing distributions in metallic
single-electron transistors. From the scale parameter we estimate the average
size of the tunnelling systems, their density of states, and the height of
their energy barrier. We conclude that the observed background charge
rearrangements predominantly take place in the substrate of the single-electron
transistor.

</DOC>
<DOC>
<DOCNO> 170471 </DOCNO>
Optimal states and almost optimal adaptive measurements for quantum


  We derive the optimal $N$-photon two-mode input state for obtaining an
estimate $\phi$ of the phase difference between two arms of an interferometer.
For an optimal measurement [B.C. Sanders and G.J. Milburn, Phys. Rev. Lett.
{\bf 75}, 2944 (1995)], it yields a variance $(\Delta \phi)^2 \simeq
\pi^2/N^2$, compared to $O(N^{-1})$ or $O(N^{-1/2})$ for states considered by
previous authors. The optimal measurement cannot be realized by counting
photons in the interferometer outputs. However, we introduce an adaptive
measurement scheme that can be thus realized, and show numerically that it
yields a variance in $\phi$ very close to that from an optimal measurement.

</DOC>
<DOC>
<DOCNO> 9051 </DOCNO>
Specific heat and high-temperature series of lattice models:


  We have developed a new method for evaluating the specific heat of lattice
spin systems. It is based on the knowledge of high-temperature series
expansions, the total entropy of the system and the low-temperature expected
behavior of the specific heat as well as the ground-state energy. By the choice
of an appropriate variable (entropy as a function of energy), a stable
interpolation scheme between low and high temperature is performed. Contrary to
previous methods, the constraint that the total entropy is log(2S+1) for a spin
S on each site is automatically satisfied. We present some applications to
quantum spin models on one- and two- dimensional lattices. Remarkably, in most
cases, a good accuracy is obtained down to zero temperature.

</DOC>
<DOC>
<DOCNO> 9655 </DOCNO>
Growth diversity in one dimensional fluctuating interfaces


  A set of one dimensional interfaces involving attachment and detachment of
$k$-particle neighbors is studied numerically using both large scale
simulations and finite size scaling analysis. A labeling algorithm introduced
by Barma and Dhar in related spin Hamiltonians enables to characterize the
asymptotic behavior of the interface width according to the initial state of
the substrate. For equal deposition--evaporation probability rates it is found
that in most cases the initial conditions induce regimes of saturated width. In
turn, scaling exponents obtained for initially flat interfaces indicate power
law growths which depend on $k$. In contrast, for unequal probability rates the
interface width exhibits a logarithmic growth for all $k > 1$ regardless of the
initial state of the substrate.

</DOC>
<DOC>
<DOCNO> 70215 </DOCNO>
Higher Twist Distribution Amplitudes of the Nucleon in QCD


  We present the first systematic study of higher-twist light-cone distribution
amplitudes of the nucleon in QCD. We find that the valence three-quark state is
described at small transverse separations by eight independent distribution
amplitudes. One of them is leading twist-3, three distributions are twist-4 and
twist-5, respectively, and one is twist-6. A complete set of distribution
amplitudes is constructed, which satisfies equations of motion and constraints
that follow from conformal expansion. Nonperturbative input parameters are
estimated from QCD sum rules.

</DOC>
<DOC>
<DOCNO> 11729 </DOCNO>
Quantum melting of the quasi-two-dimensional vortex lattice in


  We report torque magnetization measurements in regions of the mixed state
phase diagram (${\bf B}\sim\mu_o{\bf H}_{c2}$ and T$_c$/$10^3$) of the organic
superconductor $\kappa-$(ET)$_2$Cu(NCS)$_2$ where quantum fluctuations are
expected to dominate thermal effects. Over most of the field range below the
irreversibility line (${\bf B}_{irr}$), magneto-thermal instabilities are
observed in the form of flux jumps. The abrupt cessation of these instabilities
just below ${\bf B}_{irr}$ indicates a quantum melting transition from a
quasi-two-dimensional vortex lattice phase to a quantum liquid phase.

</DOC>
<DOC>
<DOCNO> 117158 </DOCNO>
Coherent time evolution of highly excited Rydberg states in pulsed


  Coherent time evolution of highly excited Rydberg states in Rb (98 < n < 150)
under pulsed electric field in high slew-rate regime was investigated with the
field ionization detection. The electric field necessary to ionize the Rydberg
states was found to take discrete values successively depending on the slew
rate. Specifically the slew-rate dependence of the ionization field varies with
the quantum defect value of the states, i.e. with the energy position of the
states relative to the adjacent manifold. This discrete transitional behavior
of the ionization field observed for the first time is considered to be a
manifestation of the strong coherence effect in the time evolution of the
Rydberg states in pulsed electric field and opens a new effective way to
stringently select a low-l state from the nearby states by field ionization.

</DOC>
<DOC>
<DOCNO> 151711 </DOCNO>
Codimension two lump solutions in string field theory and tachyonic


  We present some solutions for lumps in two dimensions in level-expanded
string field theory, as well as in two tachyonic theories: pure tachyonic
string field theory and pure $\phi^3$ theory. Much easier to handle, these
theories might be used to help understanding solitonic features of string field
theory. We compare lump solutions between these theories and we discuss some
convergence issues.

</DOC>
<DOC>
<DOCNO> 12296 </DOCNO>
Entangled Rings


  Consider a ring of N qubits in a translationally invariant quantum state. We
ask to what extent each pair of nearest neighbors can be entangled. Under
certain assumptions about the form of the state, we find a formula for the
maximum possible nearest-neighbor entanglement. We then compare this maximum
with the entanglement achieved by the ground state of an antiferromagnetic ring
consisting of an even number of spin-1/2 particles. We find that, though the
antiferromagnetic ground state does not maximize the nearest-neighbor
entanglement relative to all other states, it does so relative to other states
having zero z-component of spin.

</DOC>
<DOC>
<DOCNO> 119159 </DOCNO>
Exploring the Leo II dSph I.: The Variable Star Content


  We present the first comprehensive catalogue of variable stars in the Leo II
dwarf spheroidal galaxy. We have identified 148 RR Lyrae type variables, of
which 140 were amenable to derivation of variability parameters with our data.
We have also confirmed the existence of four anomalous Cepheids as identified
in previous studies.
  The average period of the RR Lyrae ab variables (0.62 days), the fraction of
c variables (0.24) and the minimum period of the RR Lyrae ab variables (0.51
days) all define Leo II as an "Oosterhoff intermediate" galaxy. We have used
the properties of these variables to derive a metallicity for Leo II of
approximately [Fe/H]=-1.9. The presence of longer period, higher amplitude RR
Lyrae variable implies a metallicity distribution that extends to as poor as
[Fe/H]=-2.3.
  Leo II's location on the period-metallicity relation of clusters, like that
of other ``Ootershoff intermediate'' objects, falls between the Oosterhoff
Class I and Oosterhoff Class II clusters. The properties of the variable
populations of these objects are consistent with the idea that the Oosterhoff
"dichotomy" is a continuum. The gap between the classes seems to be explained
by the horizontal branch of Galactic globular clusters shifting away from the
instability strip at at intermediate metallicities. However, Leo II, as well as
other Oosterhoff intermediate objects, has a second parameter effect strong
enough to leave horizontal branch stars in the instability strip.

</DOC>
<DOC>
<DOCNO> 178688 </DOCNO>
Simultaneous Heavy Ion Dissociation at Ultrarelativistic Energies


  We study the simultaneous dissociation of heavy ultrarelativistic nuclei
followed by the forward-backward neutron emission in peripheral collisions at
colliders. The main contribution to this particular heavy-ion dissociation
process, which can be used as a beam luminosity monitor, is expected to be due
to the electromagnetic interaction. The Weizsacker-Williams method is extended
to the case of simultaneous excitation of collision partners which is simulated
by the RELDIS code. A contribution to the dissociation cross section due to
grazing nuclear interactions is estimated within the abrasion model and found
to be relatively small.

</DOC>
<DOC>
<DOCNO> 117417 </DOCNO>
Chemo - Photometric evolution of star forming disk galaxy


  The chemical and photometric evolution of star forming disk galaxies is
investigated. Numerical simulations of the complex gasdynamical flows are based
on our own coding of the Chemo - Dynamical Smoothed Particle Hydrodynamical (CD
- SPH) approach, which incorporates the effects of star formation. As a first
application, the model is used to describe the chemical and photometric
evolution of a disk galaxy like the Milky Way.

</DOC>
<DOC>
<DOCNO> 151545 </DOCNO>
Open Branes in Space-Time Non-Commutative Little String Theory


  We conjecture the existence of two new non-gravitational six-dimensional
string theories, defined as the decoupling limit of NS5-branes in the
background of near-critical electrical two- and three-form RR fields. These
theories are space-time non-commutative Little String Theories with open
branes. The theory with (2,0) supersymmetry has an open membrane in the
spectrum and reduces to OM theory at low energies. The theory with (1,1)
supersymmetry has an open string in the spectrum and reduces to 5+1 dimensional
NCOS theory for weak NCOS coupling and low energies. The theories are shown to
be T-dual with the open membrane being T-dual to the open string. The theories
therefore provide a connection between 5+1 dimensional NCOS theory and OM
theory. We study the supergravity duals of these theories and we consider a
chain of dualities that shows how the T-duality between the two theories is
connected with the S-duality between 4+1 dimensional NCOS theory and OM theory.

</DOC>
<DOC>
<DOCNO> 99905 </DOCNO>
Grobner Basis Techniques for Computing Actions of K-Categories


  This paper involves categories and computer science. The paper is motivated
by a question which arises from two pieces of research.
  Firstly, the work of Brown and Heyworth which extends rewriting techniques to
enable the computation of left Kan extensions over the category of sets. It is
well known that left Kan extensions can be defined over categories other than
Sets.
  Secondly, the `folklore' that rewriting theory is a special case of
noncommutative Groebner basis theory. It is therefore natural to ask whether
Groebner bases can provide a method for computing Kan extensions beyond the
special case of rewriting.
  To answer this question completely, fully exploiting the computational power
of Groebner basis techniques relating to Kan extensions is the ultimate aim.
This paper provides a first step by showing how standard noncommutative
Groebner basis procedures can be used to calculate left Kan extensions of
K-category actions. In the final section of the paper a number of interesting
problems arising from the work are identified.

</DOC>
<DOC>
<DOCNO> 101317 </DOCNO>
Classifications of Simple Novikov Algebras and Their Irreducible Modules


  In this paper, we first present a classification theorem of
infinite-dimensional simple Novikov algebras over an algebraically closed field
with characteristic 0. Then we classify all the irreducible modules of a
certain infinite-dimensional simple Novikov algebras with an idempotent element
whose left action is locally finite.

</DOC>
<DOC>
<DOCNO> 178899 </DOCNO>
RPA quasi-elastic responses in infinite and finite nuclear systems


  Quasi-elastic responses in nuclear matter and in $^{12}$C and $^{40}$Ca
nuclei are calculated in ring approximation to investigate the finite size
effects on the electromagnetic quasi-elastic responses. A method to simulate
these effects in infinite systems calculations is proposed. The sensitivity of
the results to the various terms of the residual interaction is studied. The
results of nuclear matter RPA calculations are compared with those obtained in
ring approximation to evidence the importance of the exchange terms.

</DOC>
<DOC>
<DOCNO> 39967 </DOCNO>
QCD studies in e+e- annihilation from 30GeV to 189GeV


  We present results obtained from a study of the structure of hadronic events
recorded by the L3 detector at various centre-of-mass energies. The
distributions of event shape variables and the energy dependence of their mean
values are measured from 30GeV to 189GeV and compared with various QCD models.
The energy dependence of the moments of event shape variables is used to test a
power law ansatz for the non-perturbative component. We obtain a universal
value of the non-perturbative parameter alpha_0 = 0.537 +/- 0.073. From a
comparison with resummed O(alpha_s^2) QCD calculations, we determine the strong
coupling constant at each of the selected energies. The measurements
demonstrate the running of alpha_s as expected in QCD with a value of
alpha_s(m_Z) = 0.1215 +/- 0.0012 (exp) +/- 0.0061 (th).

</DOC>
<DOC>
<DOCNO> 84256 </DOCNO>
Electromagnetic waves in a wormhole geometry


  We investigate the propagation of electromagnetic waves through a static
wormhole. It is shown that the problem can be reduced to a one-dimensional
Schr\"odinger-like equation with a barrier-type potential. Using numerical
methods, we calculate the transmission coefficient as a function of the energy.
We also discuss the polarization of the outgoing radiation due to this
gravitational scattering.

</DOC>
<DOC>
<DOCNO> 8166 </DOCNO>
An approximate solution to the Boltzmann equation for vibrated granular


  The behaviour of the lower order moments of the velocity distribution
function for a system of inelastic granular disks driven by vertical vibrations
is studied using a kinetic theory. A perturbative kinetic theory for
vibro-fluidised beds was proposed by Kumaran (JFM, v. 364, 163). A scheme to
generalise this theory to higher orders in the moments is presented here. With
such a method it is possible to obtain an analytical solution to the moments of
the distribution function up to third order.

</DOC>
<DOC>
<DOCNO> 122148 </DOCNO>
Relating Galaxy Cluster X-Ray Luminosities to Gravitational Masses in


  It is shown that galaxy cluster surveys selecting clusters by their X-ray
luminosity effectively select by cluster mass. It is shown that a selection
based solely on Abell galaxy richness is less efficient in terms of mass.
Furthermore the empirical X-ray luminosity - gravitational mass relation and
its scatter is quantified and the relation is compared to predicted relations.

</DOC>
<DOC>
<DOCNO> 119546 </DOCNO>
A Pressure Anomaly for HII Regions in Irregular Galaxies


  The pressures of giant HII regions in 6 dwarf Irregular galaxies are a factor
of ~10 larger than the average pressures of the corresponding galaxy disks,
obtained from the stellar and gaseous column densities. Either the visible HII
regions in these dwarfs are all so young that they are still expanding, or
there is an unexpected source of disk self-gravity that increases the
background pressure. We consider the possibility that the additional
self-gravity comes from disk dark matter, but suggest this is unlikely because
the vertical scale heights inferred for Irregular galaxies are consistent with
the luminous matter alone. Some of the HII region overpressure is probably the
result of local peaks in the gravitational field that come from large gas
concentrations, many of which are observed directly. These peaks also explain
the anomalously low average column density thresholds for star formation that
were found earlier for Irregular galaxies, and they permit the existence of a
cool HI phase as the first step toward dense molecular cores. Many of the HII
regions could also be so strongly over-pressured that they will expand for a
long time. In this case, the observed population would be only 7% of the total,
and the aging HII regions, now too faint to see, should occupy nearly the
entire dwarf galaxy volume. Such prolonged HII region expansion would explain
the origin of the giant HI shells that are seen in these galaxies, and account
for the lack of bright central clusters inside these shells.

</DOC>
<DOC>
<DOCNO> 102641 </DOCNO>
The Homflypt skein module of a connected sum of 3-manifolds


  If M is an oriented 3-manifold, let S(M) denote the Homflypt skein module of
M. We show that S(M_1 connect sum M_2) is isomorphic to S(M_1) tensor S(M_2)
modulo torsion. In fact, we show that S(M_1 connect sum M_2) is isomorphic to
S(M_1) tensot S(M_2) if we are working over a certain localized ring. We show
the similar result holds for relative skein modules. If M contains a separating
2-sphere, we give conditions under which certain relative skein modules of M
vanish over specified localized rings.

</DOC>
<DOC>
<DOCNO> 83311 </DOCNO>
Integrating E-Commerce and Data Mining: Architecture and Challenges


  We show that the e-commerce domain can provide all the right ingredients for
successful data mining and claim that it is a killer domain for data mining. We
describe an integrated architecture, based on our expe-rience at Blue Martini
Software, for supporting this integration. The architecture can dramatically
reduce the pre-processing, cleaning, and data understanding effort often
documented to take 80% of the time in knowledge discovery projects. We
emphasize the need for data collection at the application server layer (not the
web server) in order to support logging of data and metadata that is essential
to the discovery process. We describe the data transformation bridges required
from the transaction processing systems and customer event streams (e.g.,
clickstreams) to the data warehouse. We detail the mining workbench, which
needs to provide multiple views of the data through reporting, data mining
algorithms, visualization, and OLAP. We con-clude with a set of challenges.

</DOC>
<DOC>
<DOCNO> 169583 </DOCNO>
Quantum authentication protocol


  In this letter, we proposed a quantum authentication protocol. The
authentication process is implemented by the symmetric cryptographic scheme
with quantum effects.

</DOC>
<DOC>
<DOCNO> 122933 </DOCNO>
The Starburst-AGN Connection


  The issue of a starburst-AGN connection in local and distant galaxies is
relevant for understanding galaxy formation and evolution, the star formation
and metal enrichment history of the universe, the origin of the extragalactic
background at low and high energies, and the origin of nuclear activity in
galaxies. Here I review some of the observational evidence recently brought
forward in favor of a connection between the starburst and AGN phenomena. I
conclude by raising a number of questions concerning the exact nature of this
connection.

</DOC>
<DOC>
<DOCNO> 101689 </DOCNO>
Classification theory for theories with NIP - a modest beginning


  A relevant thesis is that for the family of complete first order theories
with NIP (i.e. without the independence property) there is a substantial
theory, like the family of stable (and the family of simple) first order
theories. We examine some properties.

</DOC>
<DOC>
<DOCNO> 11630 </DOCNO>
Basis-dependent dynamics of trapped Bose-Einstein condensates and


  We present a consistent second order perturbation theory for the lowest-lying
condensed modes of very small, weakly-interacting Bose-Einstein condensates in
terms of bare particle eigenstates in a harmonic trap. After presenting our
general approach, we focus on explicit expressions for a simple three-level
system, mainly in order to discuss the analogy of a single condensate occupying
two modes of a trap with the semi-classical theory for two-mode photon lasers.
A subsequent renormalization of the single-particle energies to include the
dressing imposed by mean fields demonstrates clearly the consistency of our
treatment with other kinetic approaches.

</DOC>
<DOC>
<DOCNO> 8604 </DOCNO>
Revisiting "swings" in the crossover features of Ising thin films near


  "Swing" effects at the onset of crossover towards two dimensional behavior in
thin Ising films are investigated close to Tc(D) by means of Monte Carlo
calculations. We find that the effect is extremely large for the specific heat
effective critical exponent, in comparison with the "swing" already noted by
Capehart and Fisher for the susceptibility. These effects change considerably
the system's evolution with thickness (D) from two-dimensional to
three-dimensional behavior, forcing the effective exponents to pass near
characteristic Tri Critical Point (TCP) values.

</DOC>
<DOC>
<DOCNO> 117689 </DOCNO>
Diffusive Shock Acceleration of Electrons and Radio Emission from Large


  In present study I examine the capability of diffusive shock acceleration
mechanism to explain existing data on radio emission from evolved large
diameter shell-type adiabatic supernova remnants (SNRs). Time-dependent
''onion-shell'' model for the radio emission of SNRs is developed, which is
based on the assumptions: a) acceleration takes place from thermal energies and
test-particle approximation is valid; b) the problem of injection is avoided by
introducing, like Bell (1978), two injection parameters; c) to take into
consideration very late stages of SNR evolution the analytic approximation of
Cox and Andersen (1982) for the shell structure is used; c)no radiative
cooling. Constructed Surface Brightness - Diameter $(\Sigma -D)$ tracks are
compared with the empirical $\Sigma -D$ diagram. The main conclusion of the
study is that the DSA mechanism is capable of explaining all the statistics of
radio SNRs including very large diameter remnants and giant galactic loops.

</DOC>
<DOC>
<DOCNO> 122149 </DOCNO>
Planetary Torques as the Viscosity of Protoplanetary Disks


  We revisit the idea that density-wave wakes of planets drive accretion in
protostellar disks. The effects of many small planets can be represented as a
viscosity if the wakes damp locally, but the viscosity is proportional to the
damping length. Damping occurs mainly by shocks even for earth-mass planets.
The excitation of the wake follows from standard linear theory including the
torque cutoff. We use this as input to an approximate but quantitative
nonlinear theory based on Burger's equation for the subsequent propagation and
shock. Shock damping is indeed local but weakly so. If all metals in a
minimum-mass solar nebula are invested in planets of a few earth masses each,
dimensionless viscosities [alpha] of order dex(-4) to dex(-3) result. We
compare this with observational constraints. Such small planets would have
escaped detection in radial-velocity surveys and could be ubiquitous. If so,
then the similarity of the observed lifetime of T Tauri disks to the
theoretical timescale for assembling a rocky planet may be fate rather than
coincidence.

</DOC>
<DOC>
<DOCNO> 13211 </DOCNO>
Refinement of Bethe ansatz string and its alternative


  The well known string solution to Bethe ansatz equations is shown to be
inconsistent in its widely accepted form. A valid refinement demanding higher
order corrections in subsequent roots is identified. A new alternative string
solution is proposed for finite long chains, consistent with the non-Bethe
strings observed earlier.

</DOC>
<DOC>
<DOCNO> 152404 </DOCNO>
Instantons, Compactification and S-duality in N=4 SUSY Yang-Mills Theory


  We present a semiclassical calculation of instanton effects in N=4
supersymmetric Yang-Mills theory formulated on R^{3}XS^{1} and also in the N=1
theory obtained by introducing chiral multiplet masses. In the N=4 case, these
instanton effects are related to the bulk contribution to the index which
counts BPS dyons in the corresponding four dimensional theory. In both cases,
the calculations provide semiclassical tests of recently proposed exact results
for the lowest non-trivial terms in the derivative expansion of the Wilsonian
effective action.

</DOC>
<DOC>
<DOCNO> 68817 </DOCNO>
Self-tuning in an Outgoing Brane Wave Model


  We introduce a new brane-world model in which the bulk solution consists of
outgoing plane waves. This is an exact solution to string theory with no naked
singularities. The recently discussed self-tuning mechanism to cancel the
cosmological constant on a brane is naturally incorporated. We show that even
if the vacuum energy on the brane changes, e.g. due to a phase transition, the
brane geometry remains insensitive to the local vacuum energy. We also consider
the static self-tuning branes introduced earlier, and find a solution in which
the brane geometry starts to contract when the vacuum energy on the brane
changes.

</DOC>
<DOC>
<DOCNO> 13884 </DOCNO>
Modelling Two-Roton Bound State Formation in Fractional Quantum Hall


  Composite Fermion approach using extensive and parallalized numerical
analysis has recently established a two-roton bound state as the lowest energy
long wavelength neutral excitation of FQHE for finite particle (N~30) system.
By focussing on the "oriented dipole" character of magneto roton, we model the
two roton problem and solve it variationally (analytically) to find a two-roton
bound state with binding energy which is in good agreement with the composite
fermion numerical results.

</DOC>
<DOC>
<DOCNO> 12095 </DOCNO>
Free cooling of particles with rotational degrees of freedom


  Free cooling of granular materials is analyzed on the basis of a
pseudo-Liouville operator. Exchange of translational and rotational energy
requires surface roughness for spherical grains, but occurs for non-spherical
grains, like needles, even if they are perfectly smooth. Based on the
assumption of a homogeneous cooling state, we derive an approximate analytical
theory. It predicts that cooling of both rough spheres and smooth needles
proceeds in two stages: An exponentially fast decay to a state with stationary
ratio of translational and rotational energy and a subsequent algebraic decay
of the total energy. These results are confirmed by simulations for large
systems of moderate density. For higher densities, we observe deviations from
the homogeneous state as well as large-scale structures in the velocity field.
We study non-Gaussian distributions of the momenta perturbatively and observe a
breakdown of the expansion for particular values of surface roughness and
normal restitution.

</DOC>
<DOC>
<DOCNO> 70612 </DOCNO>
Thermal forward scattering amplitudes in temporal gauges


  We employ the thermal forward scattering amplitudes technique in order to
compute the gluon self-energy in a class of temporal gauges. The leading T^2
and the sub-leading ln(T) contributions are obtained for temperatures high
compared with the external momentum. The logarithmic contributions have the
same structure as the ultraviolet pole terms which occur at zero temperature
(we have recently extended this result to the Coulomb gauge). We also show that
the prescription poles, characteristic of temporal gauges, do not modify the
leading and sub-leading high-temperature behavior. The one-loop calculation
shows that the thermal self-energy is transverse. This result has also been
extended to higher orders, using the BRS identities.

</DOC>
<DOC>
<DOCNO> 118580 </DOCNO>
Protostellar Collapse with Various Metallicities


  The thermal and chemical evolution of gravitationally collapsing protostellar
clouds is investigated, focusing attention on their dependence on metallicity.
Calculations are carried out for a range of metallicities spanning the local
interstellar value to zero. During the time when clouds are transparent to
continuous radiation, the temperatures are higher for those with lower
metallicity, reflecting lower radiative ability. However, once the clouds
become opaque, in the course of the adiabatic contraction of the transient
cores, their evolutionary trajectories in the density-temperature plane
converge to a unique curve that is determined by only physical constants. The
trajectories coincide with each other thereafter. Consequently, the size of the
stellar core at the formation is the same regardless of the gas composition of
the parent cloud.

</DOC>
<DOC>
<DOCNO> 118078 </DOCNO>
Determination of cosmological parameters from large scale structure


  The possibility of determining cosmological parameters on the basis of a wide
set of observational data including the Abell-ACO cluster power spectrum and
mass function, peculiar velocities of galaxies, the distribution of Ly-$\alpha$
clouds and CMB temperature fluctuations is analyzed. Using a $\chi^2$
minimization method, assuming $\Omega_{\Lambda}+\Omega_m =1$ and no
contribution from gravity waves, we found that a tilted $\Lambda$MDM model with
one sort of massive neutrinos and the parameters $n\approx 1.12$,
$\Omega_m\approx 0.4$ ($\Omega_{\Lambda}\approx 0.6$), $\Omega_{cdm}\approx
0.3$, $\Omega_{\nu}\approx 0.06$, $\Omega_b\approx 0.04$ and $h\approx 0.7$
matches observational data best. $\Omega_{\nu}$ is higher for more species of
massive neutrinos, $\sim 0.1$ for two and $\sim 0.13$ for three species.
$\Omega_m$ raises by $\sim 0.08$ and $\sim 0.15$ respectively.
  Varying only a subset of parameters and fixing the others shows also that the
observational data set used here rules out pure CDM models with $h\ge 0.5$,
scale invariant primordial power spectrum, zero cosmological constant and
spatial curvature at a very high confidence level, $>99.99%$. The corresponding
class of MDM models are ruled out at $\sim 95%$ C.L.
  It is notable also that this data set determines the amplitude of scalar
fluctuations approximately at the same level as COBE four-year data. It
indicates that a possible tensor component in the COBE data cannot be very
substantial.

</DOC>
<DOC>
<DOCNO> 69409 </DOCNO>
The neutrino star in the bulk Universe


  Motivated by the Kaluza-Klein theory with large extra spacetime dimensions
the neutrino star built from the massive sterile neutrinos core and the
massless brane neutrinos envelope is presented. The six - dimensional
compactification scale ~15 MeV gives the maximal neutrino mass M_max = 2.3 10^4
of the solar mass with the radius R_max = 1.2 10^6 km . The maximal neutrino
star parameters varies with temperature. In the limit of the neutrino ball
approximation the maximal sterile neutrino star is M_max = 1.1 10^6 of the
solar mass.

</DOC>
<DOC>
<DOCNO> 119047 </DOCNO>
Time-series spectroscopy of the rapidly oscillating Ap star HR 3831


  We present time-series spectroscopy of the rapidly oscillating Ap star HR
3831. This star has a dominant pulsation period of 11.7 minutes and a rotation
period of 2.85 days. We have analysed 1400 intermediate-resolution spectra of
the wavelength region 6100--7100 AA obtained over one week, using techniques
similar to those we applied to another roAp star, Alpha Cir.
   We confirm that the H-alpha velocity amplitude of HR 3831 is modulated with
rotation phase. Such a modulation was predicted by the oblique pulsator model,
and rules out the spotted pulsator model. However, further analysis of H-alpha
and other lines reveal rotational modulations that cannot easily be explained
using the oblique pulsator model. In particular, the phase of the pulsation as
measured by the width of the H-alpha line varies with height in the line.
   The variation of the H-alpha bisector shows a very similar pattern to that
observed in Alpha Cir, which we have previously attributed to a radial node in
the stellar atmosphere. However, the striking similarities between the two
stars despite the much shorter period of Alpha Cir (6.8 min) argues against
this interpretation unless the structure of the atmosphere is somewhat
different between the two stars. Alternatively, the bisector variation is a
signature of the degree l of the mode and not the overtone value n.
   High-resolution studies of the metal lines in roAp stars are needed to
understand fully the form of the pulsation in the atmosphere.

</DOC>
<DOC>
<DOCNO> 9537 </DOCNO>
Slow Logarithmic Decay of Magnetization in the Zero Temperature Dynamics


  We study the zero temperature coarsening dynamics in an Ising chain in
presence of a dynamically induced field that favors locally the `-' phase
compared to the `+' phase. At late times, while the `+' domains still
coarsen as $t^{1/2}$, the `-' domains coarsen slightly faster as $t^{1/2}\log
(t)$. As a result, at late times, the magnetization decays slowly as, $m(t)=-1
+{\rm const.}/{\log (t)}$. We establish this behavior both analytically within
an independent interval approximation (IIA) and numerically. In the zero volume
fraction limit of the `+' phase, we argue that the IIA becomes asymptotically
exact. Our model can be alternately viewed as a simple Ising model for granular
compaction. At late times in our model, the system decays into a fully compact
state (where all spins are `-') in a slow logarithmic manner $\sim 1/{\log
(t)}$, a fact that has been observed in recent experiments on granular systems.

</DOC>
<DOC>
<DOCNO> 152396 </DOCNO>
Discrete Torsion, Covering Groups and Quiver Diagrams


  Without recourse to the sophisticated machinery of twisted group algebras,
projective character tables and explicit values of 2-cocycles, we here present
a simple algorithm to study the gauge theory data of D-brane probes on a
generic orbifold G with discrete torsion turned on. We show in particular that
the gauge theory can be obtained with the knowledge of no more than the
ordinary character tables of G and its covering group G*. Subsequently we
present the quiver diagrams of certain illustrative examples of SU(3)-orbifolds
which have non-trivial Schur Multipliers. The paper serves as a companion to
our earlier work (arXiv:hep-th/0010023) and aims to initiate a systematic and
computationally convenient study of discrete torsion.

</DOC>
<DOC>
<DOCNO> 13838 </DOCNO>
Interplay of real space and momentum space topologies in strongly


  We discuss the momentum-space topology of 3+1 and 2+1 strongly correlated
fermionic systems. For the 3+1 systems the important universality class is
determined by the topologically stable Fermi points in momentum space. In the
extreme limit of low energy the condensed matter system of this universality
class acquires all the symmetries, which we know today in high energy physics:
Lorentz invariance, gauge invariance, general covariance, etc. The chiral
fermions as well as gauge bosons and gravity field arise as fermionic and
bosonic collective modes of the system. This introduces the conceptual
similarity between such condensed matter and the quantum vacuum of Standard
Model, which also contains the Fermi point. For the 2+1 fermionic systems the
momentum space topology gives rise to the quantization of different physical
parameters, such as Hall conducivity and spin-Hall conductivity, and to quantum
phase transitions with the abrupt change of the momentum-space topology. The
combined p-space and r-space topology determines in particular the topology of
the energy spectrum of fermion zero modes living within the topological
defects; fermionic charges of the topologically nontrivial extended objects;
axial anomaly; etc.

</DOC>
<DOC>
<DOCNO> 150906 </DOCNO>
Logarithmic Behaviours in the Feigin-Fuchs Construction of the c=-2


  We obtain logarithmic behaviours of a four-point correlation function in the
c=-2 conformal field theory by using the Feigin-Fuchs construction. It becomes
an indeterminate form by a naive evaluation, but is obtained by introducing an
appropriate regularization procedure.

</DOC>
<DOC>
<DOCNO> 170439 </DOCNO>
Molecular-Coherent-States and Molecular-Fundamental-States


  New families of Molecular-Coherent-States are constructed by the Perelomov
group-method. Each family is generated by a Molecular-Fundamental-State that
depends on an arbitrary sequence of complex numbers cj. Two of these families
were already obtained by D.Janssen and by J. A. Morales, E. Deumens and Y.
Ohrn. The properties of these families are investigated and we show that most
of them are independent on the cj.

</DOC>
<DOC>
<DOCNO> 68114 </DOCNO>
How precisely can the difference method determine the pion-nucleon


  The Coulomb-like backward peak of the neutron-proton scattering differential
cross section is due to one-pion exchange. Extrapolation to the pion pole of
precise data should allow to obtain the value of the charged pion-nucleon
coupling constant. This was classically attempted by the use of a smooth
physical function, the Chew function, built from the cross section. To improve
accuracy of such an extrapolation one has introduced a difference method. It
consists of extrapolating the difference between the Chew function based on
experimental data and that built from a model where the pion-nucleon coupling
is exactly known. Here we cross-check to which precision can work this novel
extrapolation method by applying it to differences between models and between
data and models. With good reference models and for the 162 MeV neutron-proton
Uppsala single energy precise data with a normalisation error of 2.3 %, the
value of the charged pion-nucleon coupling constant is obtained with an
accuracy close to 1.8 %.

</DOC>
<DOC>
<DOCNO> 9842 </DOCNO>
The Hubbard Model, Spinless Fermions, and Ising Spins


  The Hubbard model is used to study an electronic system at half filling.
Starting from a functional integral representation the spin-up Grassmann field
is integrated out. It is shown that the resulting spinless fermion theory has
an instantaneous cluster interaction, and that the spinless fermions are
coupled to thermally fluctuating Ising spins. The coupling parameter of the
spinless fermion interaction is a product of the Hubbard interaction and the
hopping rate. As an example the strongly metallic as well as the strongly
insulating regime are investigated in terms of the effective Ising statistics.

</DOC>
<DOC>
<DOCNO> 120634 </DOCNO>
Uncertainties on Clusters of Galaxies Distances


  We investigate in this paper the error on the cluster redshift estimate as a
function of: (1) the number of galaxy structures along the line of sight; (2)
the morphology of the clusters (regular/substructures); (3) the nature of the
observed galaxies (cD/normal galaxies); (4) the number of observed galaxies;
and (5) the distance of the clusters. We find that if we use cD galaxies we
have errors of less than 2% (at the 1-$\sigma$ level) for the cluster distances
except when the clusters are very complex. In those cases when we use five
redshift measurements along the cluster lines of sight to compute the mean
redshift, the mean redshift estimate error is less than 5% for the clusters
closer than z=0.30. The same error of 5% for clusters in z=[0.30;0.60] requires
about 12 redshifts measurements.

</DOC>
<DOC>
<DOCNO> 14096 </DOCNO>
Delocalized quasiparticles throughout the vortex state in s-wave


  Quasiparticle transport in the vortex state of an s-wave superconductor at T
-> 0 was investigated by measuring the thermal conductivity of LuNi_2B_2C down
to 70 mK in a magnetic field perpendicular to the heat current. In zero field,
there is no electronic conduction, as expected for a superconducting gap
without nodes. However, as soon as vortices enter the sample quasiparticles are
seen to conduct remarkably well, even better than they would in a typical
d-wave superconductor. This is in stark conflict with the widely held view that
quasiparticle states in s-wave superconductors just above H_{c1} should be
localized and bound to the vortex core.

</DOC>
<DOC>
<DOCNO> 68483 </DOCNO>
Electroweak Baryogenesis: Concrete in a SUSY Model with a Gauge Singlet


  SUSY models with a gauge singlet easily allow for a strong first order
electroweak phase transition (EWPT) if the vevs of the singlet and Higgs fields
are of comparable size. We discuss the profile of the stationary expanding
bubble wall and CP-violation in the effective potential, in particular
transitional CP-violation inside the bubble wall during the EWPT. The
dispersion relations for charginos contain CP-violating terms in the WKB
approximation. These enter as source terms in the Boltzmann equations for the
(particle--antiparticle) chemical potentials and fuel the creation of a baryon
asymmetry through the weak sphaleron in the hot phase. This is worked out for
concrete parameters.

</DOC>
<DOC>
<DOCNO> 101786 </DOCNO>
The dihedral Lie algebras and Galois symmetries of \pi_1^l(P^1 - 0,


  We study the action of the Galois group on the pro-l-completion of the
fundamental group of P^1 - {0, infinity and N-th roots of unity}. We describe
the Lie algebra of the image of the Galois action and relate with the geometry
of the modular varieties for GL_m for m = 1,2,3,...
  This story is the l-adic side of the motivic theory of multiple
polylogarithms at roots of unity, which generalize the classical cyclotomy
theory.

</DOC>
<DOC>
<DOCNO> 170470 </DOCNO>
Quantum Magic Bullets via Entanglement


  Two particles that are entangled with respect to continuous variables such as
position and momentum exhibit a variety of nonclassical features. First,
measurement of one particle projects the other particle into the state that is
the complex conjugate of the state of the first particle, i.e., measurement of
one particle projects the other particle into the time-reversed state. Second,
continuous-variable entanglement can be used to implement a quantum "magic
bullet": when one particle manages to pass through a scattering potential, then
no matter how low the probability of this event, the second particle will also
pass through a related scattering potential with probability one. This
phenomenon is investigated in terms of the original EPR state, and experimental
realizations are suggested in terms of entangled photon states.

</DOC>
<DOC>
<DOCNO> 9963 </DOCNO>
Exactly Soluble Model for Nuclear Liquid-Gas Phase Transition


  Thermodynamical properties of nuclear matter undergoing multifragmentation
are studied within a simplified version of the statistical model. An exact
analytical solution has been found for the grand canonical ensemble. Excluded
volume effects are taken into account in the thermodynamically self-consistent
way. In thermodynamic limit the model exhibits a first order liquid-gas phase
transition with specific mixed phase properties. An extension of the model
including the Fisher's term is also studied. The possibility of the second
order phase transition at or above the critical point is demonstrated. The
fragment mass distributions in the different regions of the phase diagram are
discussed.

</DOC>
<DOC>
<DOCNO> 151365 </DOCNO>
On covariant $\kappa-$symmetry fixing and the relation betwen the NSR


  By considering the superembedding equation for the Type II superstring we
derive the classical relation between the NSR string and the Type II GS
superstring Grassmannian variables. The connection between the actions of these
two models is also established. Then introducing the proper twistor-like
Lorentz harmonic variables we fix $\kappa-$symmetry of the GS formulation in
the manifestly SO(1,9) Lorentz covariant manner and establish the relation
between the gauge-fixed variables of the NSR and the Type II GS models.

</DOC>
<DOC>
<DOCNO> 150498 </DOCNO>
Non-commutative vs. Commutative Descriptions of D-brane BIons


  The U(1) gauge theory on a D3-brane with non-commutative worldvolume is shown
to admit BIon-like solutions which saturate a BPS bound on the energy. The
mapping of these solutions to ordinary fields is found exactly, namely
non-perturbatively in the non-commutativity parameters. The result is precisely
an ordinary supersymmetric BIon in the presence of a background B-field. We
argue that the result provides evidence in favour of the exact equivalence of
the non-commutative and the ordinary descriptions of D-branes.

</DOC>
<DOC>
<DOCNO> 119040 </DOCNO>
Keck Observations of the Hidden Quasar IRAS P09104+4109


  We present imaging and spectro- polarimetric observations of the
ultraluminous infrared galaxy IRAS P09104+4109 using the Keck 10-m Telescope.
We detect the clear presence of broad Hb, Hg, and MgII 2800 emission lines in
the polarized flux spectra of the nucleus and of an extranuclear emission
region ~ 4" away, confirming the presence of a hidden central quasar. The
polarization of the broad Mg II emission line is high (~ 29%), consistent with
the remarkably high polarization (~ 30%-40%) observed in the extended continuum
emission. The narrow emission lines are polarized in a stratified fashion, with
the high ionization lines being polarized 0.7%-1.7% and [O II] essentially
unpolarized. The line polarizations are positively correlated with critical
density, ionization potential, and velocity width of the emission lines. This
indicates that the NLR may be partially shadowed by the putative torus, with
the higher ionization lines originating closer to the nucleus. One notable
characteristic of the extranuclear knot is that all species of Fe are markedly
absent in its spectrum, while they appear prominently in the nucleus. Our
favored interpretation is that there is a large amount of dust in the
extranuclear regions, allowing gaseous refractory metals to deposit. The
extended emission regions are most likely material shredded from nearby cluster
members and not gas condensed from the cooling flow or expelled from the
obscured quasar. Our data provide strong evidence for matter-bounded clouds in
addition to ionization-bounded clouds in the NLR. Ionization by pure velocity
shocks can be ruled out. Shocks with photoionizing precursors may be present,
but are probably not a dominant contributor to the energy input.

</DOC>
<DOC>
<DOCNO> 69890 </DOCNO>
Time-reversal-violating birefringence of photon in a medium exposed to


  The T-reversal-violating optical gyrotropy is discussed. An expression for
dielectric permittivity describing T-reversal-violating phenomena in a medium
exposed to external electric and magnetic fields is presented. Optical
phenomena of birefringence and polarization plane rotation of photon in a
medium exposed to external electric and magnetic fields are considered.

</DOC>
<DOC>
<DOCNO> 150715 </DOCNO>
Axial current in QED and semi-naive dimensional renormalization


  We renormalize at two loops the axial current and $F \tilde{F}$ in massless
QED, using the recently proposed semi-naive dimensional renormalization scheme.
We show that the results are in agreement with those in the
Breitenlohner-Maison-'t Hooft-Veltman scheme, previously obtained indirectly by
making a three-loop computation.

</DOC>
<DOC>
<DOCNO> 14111 </DOCNO>
Correct extrapolation of overlap distribution in spin glasses


  We study in d=3 dimensions the short range Ising spin glass with Jij=+/-1
couplings at T=0. We show that the overlap distribution is non-trivial in the
limit of large system size.

</DOC>
<DOC>
<DOCNO> 72108 </DOCNO>
Two-Loop Renormalization of Heavy--Light Currents at Order 1/m_Q in the


  We present exact results, at next-to-leading order in renormalization-group
improved perturbation theory, for the Wilson coefficients appearing at order
1/m_Q in the heavy-quark expansion of heavy-light current operators. To this
end, we complete the calculation of the corresponding two-loop anomalous
dimension matrix. Our results are important for determinations of |V_{ub}|
using exclusive and inclusive semileptonic B decays. They are also relevant to
computations of the decay constant f_B based on a heavy-quark expansion.

</DOC>
<DOC>
<DOCNO> 10119 </DOCNO>
Controlled Phase Separation in La_0.5 Ca_0.5 Mn O_3


  A systematic study of phase separation effects in polycrystalline La_0.5
Ca_0.5 Mn O_3 obtained under different thermal treatments is reported. Samples
with average grain size ranging from 200 to 1300 nm were studied. Magnetic and
electrical measurements show quantitative differences among samples in their
low temperature behavior. indicating that the fraction of the ferromagnetic
(FM) phase gradually decreases as the grain size increase. Percolation of the
FM phase in samples with a small fraction of this phase suggests that grain
boundaries play a distinctive role in the spatial distribution of coexisting
phases. The defective structure at the grain surface could explain the local
inhibition of the antiferromagnetic charge ordered phase, an effect that is
gradually removed with increasing grain size. Qualitative agreement of the data
with this description is found. This effect is also found to be highly
dependent on the oxygen content of the samples and its spatial distribution.

</DOC>
<DOC>
<DOCNO> 152321 </DOCNO>
Scale Invariance and the AdS/CFT Correspondence


  Using the AdS/CFT correspondence, we show that the Anti-de Sitter (AdS)
rotating (Kerr) black holes in five and seven dimensions provide us with
examples of non-trivial field theories which are scale, but not conformally
invariant. This is demonstrated by our computation of the actions and the
stress-energy tensors of the four and six dimensional field theories residing
on the boundary of these Kerr-AdS black holes spacetimes.

</DOC>
<DOC>
<DOCNO> 118430 </DOCNO>
A Population of very young Brown Dwarfs and free-floating Planets in


  We describe the results of a very deep imaging survey of the Trapezium
Cluster in the IJH bands, using the UKIRT high resolution camera UFTI.
Approximately 32% of the 515 point sources detected are brown dwarf candidates,
including several free floating objects with masses below the Deuterium burning
(planetary) threshold at 0.013 solar masses, which are detectable because of
their extreme youth. We have confidence that almost all the sources detected
are cluster members, since foreground contamination is minimal in the 33
arcmin^2 area surveyed and the dense backdrop of OMC-1 obscures all background
stars at these wavelengths. Extinction is calculated from the (J-H)colours,
permitting accurate luminosity estimates and temperatures are derived from the
dereddened (I-J) colours. There is some evidence for a cut-off in the
luminosity function below the level corresponding to several Jupiter masses,
which may represent the bottom end of the IMF. Since star formation is complete
in the Trapezium this limit could have wide significance, if confirmed.
However, it could well be an effect of the dispersal of the molecular cloud by
the central O-type stars, a process whose timescale will vary between star
formation regions.

</DOC>
<DOC>
<DOCNO> 71018 </DOCNO>
Do We Understand the Sphaleron Rate?


  I begin by answering a different question, ``Do we know the sphaleron rate?''
and conclude that we do. Then I discuss a crude but purely analytic picture
which provides an estimate of the sphaleron rate within the context of
Bodeker's effective theory. The estimate, which comes surprisingly close to the
numerically determined sphaleron rate, gives a physical picture of baryon
number violation in the hot phase, and provides a conjecture of the Nc
dependence of the sphaleron rate in SU(Nc) gauge theory.

</DOC>
<DOC>
<DOCNO> 39773 </DOCNO>
Confidence limits: what is the problem? Is there the solution?


  This contribution to the debate on confidence limits focuses mostly on the
case of measurements with `open likelihood', in the sense that it is defined in
the text. I will show that, though a prior-free assessment of {\it confidence}
is, in general, not possible, still a search result can be reported in a mostly
unbiased and efficient way, which satisfies some desiderata which I believe are
shared by the people interested in the subject. The simpler case of `closed
likelihood' will also be treated, and I will discuss why a uniform prior on a
sensible quantity is a very reasonable choice for most applications. In both
cases, I think that much clarity will be achieved if we remove from scientific
parlance the misleading expressions `confidence intervals' and `confidence
levels'.

</DOC>
<DOC>
<DOCNO> 151473 </DOCNO>
Superembeddings, Partial Supersymmetry Breaking and Superbranes


  It is advocated that the superembedding approach is a generic covariant
method for the description of superbranes as models of (partial) spontaneous
supersymmetry breaking. As an illustration we construct (in the framework of
superembeddings) an n=1, d=3 worldvolume superfield action for a supermembrane
propagating in N=1, D=4,5,7 and 11-dimensional supergravity backgrounds. We
then show how in the case of an N=1, D=4 target superspace gauge fixing local
worldvolume superdiffeomorphisms in the covariant supermembrane action results
in an effective N=2, d=3 supersymmetric field theory with N=2 supersymmetry
being spontaneously broken down to N=1. The broken part of N=2, d=3
supersymmetry is nonlinearly realized when acting on Goldstone N=1, d=3
superfields, which describe physical degrees of freedom of the model. As an
introduction to the formalism, the procedure of getting effective field
theories with partially broken supersymmetry by gauge fixing covariant
superbrane actions is also demonstrated with a simpler example of a massive
N=2, D=2 superparticle.

</DOC>
<DOC>
<DOCNO> 84097 </DOCNO>
Rotating 5D-Kaluza-Klein Space-Times from Invariant Transformations


  Using invariant transformations of the five-dimensional Kaluza-Klein (KK)
field equations, we find a series of formulae to derive axial symmetric
stationary exact solutions of the KK theory starting from static ones. The
procedure presented in this work allows to derive new exact solutions up to
very simple integrations. Among other results, we find exact rotating solutions
containing magnetic monopoles, dipoles, quadripoles, etc., coupled to scalar
and to gravitational multipole fields.

</DOC>
<DOC>
<DOCNO> 13069 </DOCNO>
Delocalization effects and charge reorganizations induced by repulsive


  We study the delocalization effect of a short-range repulsive interaction on
the ground state of a finite density of spinless fermions in strongly
disordered one dimensional lattices. The density matrix renormalization group
method is used to explore the charge density and the sensitivity of the ground
state energy with respect to the boundary condition (the persistent current)
for a wide range of parameters (carrier density, interaction and disorder).
Analytical approaches are developed and allow to understand some mechanisms and
limiting conditions. For weak interaction strength, one has a Fermi glass of
Anderson localized states, while in the opposite limit of strong interaction,
one has a correlated array of charges (Mott insulator). In the two cases, the
system is strongly insulating and the ground state energy is essentially
invariant under a twist of the boundary conditions. Reducing the interaction
strength from large to intermediate values, the quantum melting of the solid
array gives rise to a more homogeneous distribution of charges, and the ground
state energy changes when the boundary conditions are twisted. In individual
chains, this melting occurs by abrupt steps located at sample-dependent values
of the interaction where an (avoided) level crossing between the ground state
and the first excitation can be observed. Important charge reorganizations take
place at the avoided crossings and the persistent currents are strongly
enhanced around the corresponding interaction value. These large delocalization
effects become smeared and reduced after ensemble averaging. They mainly
characterize half filling and strong disorder, but they persist away of this
optimal condition.

</DOC>
<DOC>
<DOCNO> 84591 </DOCNO>
Hamiltonian formalism with several variables and quantum field theory,


  We discuss in this paper the canonical structure of classical field theory in
finite dimensions within the {\it{pataplectic}} hamiltonian formulation, where
we put forward the role of Legendre correspondance. We define the Poisson
$\mathfrak{p}$-brackets and $\mathfrak{\omega}$-brackets which are the
analogues of the Poisson bracket on forms. We formulate the equations of motion
of forms in terms of $\mathfrak{p}$-brackets and $\mathfrak{\omega}$-brackets
with the $n$-form ${\cal H}\omega $. As illustration of our formalism we
present two examples: the interacting scalar fields and conformal string
theory.

</DOC>
<DOC>
<DOCNO> 40153 </DOCNO>
The Cleo III Ring Imaging Cherenkov Detector


  The CLEO detector has been upgraded to include a state of the art particle
identification system, based on the Ring Imaging Cherenkov Detector (RICH)
technology, in order to take data at the upgraded CESR electron positron
collider. The expected performance is reviewed, as well as the preliminary
results from an engineering run during the first few months of operation of the
CLEO III detector.

</DOC>
<DOC>
<DOCNO> 117757 </DOCNO>
Optical surface photometry of radio galaxies - II. Observations and data


  Optical imaging observations for 50 radio galaxies are presented. For each
object isophotal contours, photometric profiles, structural parameters
(position angle, ellipticity, Fourier coefficients), and total magnitudes are
given. These observations, obtained in the Cousins R band, complement the data
presented in a previous paper and are part of a larger project aimed at
studying the optical properties of low redshift (z<0.12) radio galaxies (Govoni
et al. 1999). Comments for each individual source are reported.

</DOC>
<DOC>
<DOCNO> 80908 </DOCNO>
Dirac and Gor'kov spectra in two color QCD with chemical potential


  We analyze the eigenvalue spectrum of the staggered Dirac matrix in two-color
QCD at nonzero baryon density when the eigenvalues become complex. The
quasi-zero modes and their role for chiral symmetry breaking and the
deconfinement transition are examined. The bulk of the spectrum and its
relation to quantum chaos is considered. A comparison with predictions from
random matrix theory is presented. An analogous analysis is performed for the
spectrum of the Gor'kov representation of the fermionic action.

</DOC>
<DOC>
<DOCNO> 11448 </DOCNO>
Can nonlocal Dirac operators be topologically proper ?


  By examining the analyticity of a sequence of topologically-proper lattice
Dirac operators, we show that they tend to a nonlocal Dirac operator. This
implies that a nonlocal lattice Dirac operator can have exact zero modes
satisfying the Atiyah-Singer index theorem, in gauge backgrounds with nonzero
topological charge.

</DOC>
<DOC>
<DOCNO> 170766 </DOCNO>
Quantum Walks On Graphs


  We initiate the study of the generalization of random walks on finite graphs
to the quantum world. Such quantum walks do not converge to any stationary
distribution, as they are unitary and reversible.
 However, by suitably relaxing the definition, we can obtain a measure of how
fast the quantum walk spreads or how confined the quantum walk stays in a small
neighborhood. We give definitions of mixing time, filling time, dispersion
time. We show that in all these measures, the quantum walk on the cycle is
almost quadratically faster then its classical correspondent. On the other
hand, we give a lower bound on the possible speed up by quantum walks for
general graphs, showing that quantum walks can be at most polynomially faster
than their classical counterparts.

</DOC>
<DOC>
<DOCNO> 80744 </DOCNO>
Meron Pairs and Fermion Zero Modes


  Merons, conjectured as a semiclassical mechanism for color confinement in
QCD, have been described analytically by either infinite action configurations
or an Ansatz with discontinuous action. We construct a smooth, finite action,
stationary lattice solution corresponding to a meron pair. We also derive an
analytical solution for the zero mode of the meron pair Ansatz, show that it
has the qualitative behavior of the exact zero mode of the lattice solution,
and propose the use of zero modes to identify meron gauge field configurations
in stochastic evaluations of the lattice QCD path integral.

</DOC>
<DOC>
<DOCNO> 68181 </DOCNO>
Anomalous quartic couplings in six-fermion processes at the Linear


  The dimension-four genuine anomalous quartic couplings are studied in
processes of six-fermion production via e+e- collisions. Complete tree-level
electroweak calculations are performed including initial-state-radiation and
beamstrahlung. The analysis of final-state distributions can be used to find
kinematical cuts to enhance the effects of anomalous couplings. For the
parameters of the custodial-symmetry-conserving anomalous couplings a
sensitivity in the range between 10^{-3} and 10^{-2} can be expected at 1 TeV.

</DOC>
<DOC>
<DOCNO> 9356 </DOCNO>
Topological Defects in Spin Density Waves


  The rich order parameter of Spin Density Waves allows for unusual object of a
complex topological nature: a half-integer dislocation combined with a
semi-vortex of a staggered magnetization. It becomes energetically preferable
to ordinary dislocation due to enhanced Coulomb interactions in the
semiconducting regime. Generation of these objects changes e.g. the narrow band
noise frequency.

</DOC>
<DOC>
<DOCNO> 120603 </DOCNO>
Interstellar Seeing. II. The Case of the Vela Pulsar: Source Unresolved


  I use a method based on interstellar scintillations for discerning
information about source sizes on scales less than one micro-arc sec. I use a
comprehensive model for a pulsar signal, scintillated amplitude modulated
noise, that includes source fluctuations and noise statistics. The method takes
into account time-frequency averaging in the signal processing as well as
effects due to source structure. The method is applied to interferometric
visibility data on the Vela pulsar which show slightly less scintillation
modulation than expected for a point source in the strong scattering regime.
The decreased scintillation modulation is likely to be due exclusively to
time-frequency averaging rather than from any source size effects. The implied
upper limit on source extent, derived through Bayesian inference, is compared
to predictions that take into account beaming from the relativistic plasma flow
in neutron star magnetospheres. The upper limit for the transverse source size
($\lesssim 400$ km at 95% confidence for a pulsar distance of 0.5 kpc) is
easily consistent with conventional models for radio emission regions in pulsar
magnetospheres that place them well inside the light cylinder at only a few
neutron-star radii from the star's surface.

</DOC>
<DOC>
<DOCNO> 13720 </DOCNO>
Stabilization of ratchet dynamics by weak periodic signals


  We study the influence of weak periodic signals on the transport properties
of underdamped ratchets. We find that the constant current intervals related to
the ratchet, can be significantly enlarged by a weak subharmonic signal which
is in phase with the internal driver. This stabilization phenomenon is found to
exist both in absence and in presence of noise. The dependence of this effect
on the phase of the applied signal is also investigated.

</DOC>
<DOC>
<DOCNO> 120360 </DOCNO>
An Efficient Search for Gravitationally-Lensed Radio Lobes


  We performed an automated comparison of the FIRST radio survey with the APM
optical catalog to find radio lobes with optical counterparts. Based on an
initial survey covering ~3000 square degrees, we selected a sample of 33 lens
candidates for VLA confirmation. VLA and optical observations of these
candidates yielded two lens systems, one a new discovery (J0816+5003), and one
of which was previously known (J1549+3047). Two other candidates have radio
lobes with galaxies superposed, but lack evidence of multiple imaging. One of
our targets (J0958+2947) is a projected close pair of quasars (8'' separation
at redshifts 2.064 and 2.744). Our search method is highly efficient, with >5%
of our observing targets being lensed, compared to the usual success rate of
<1%. Using the whole FIRST survey, we expect to find 5--10 lenses in short
order using this approach, and the sample could increase to hundreds of lensed
lobes in the Northern sky, using deeper optical surveys and planned upgrades to
the VLA. Such a sample would be a powerful probe of galaxy structure and
evolution.

</DOC>
<DOC>
<DOCNO> 9805 </DOCNO>
Effect of spin-orbit impurity scattering in the superconducting state of


  We study the effect of magnetic impurities in the d_{x^2-y^2}-wave
superconducting (SC) state of the two dimensional t-J model.The spin-orbit and
the spin-exchange interactions are examined by treating the impurity as a
classical spin. The Bogoliubov de Gennes equation derived within a slave-boson
mean-field approximation is solved numerically at T = 0. The spin-exchange
scattering induces spin-triplet p-wave SC order parameters near the impurity,
while a SC state with broken time-reversal symmetry and a spontaneous current
appears in the presence of the spin-orbit interaction. When both interactions
coexist, it turns out that a state which carries a spontaneous spin current
occurs.

</DOC>
<DOC>
<DOCNO> 68993 </DOCNO>
Charm in nuclear reactions in sqrt(s)=17 and 19 GeV


  Consequences resulting from the D Dbar excess derived indirectly by the NA50
experiment in S+U and Pb+Pb collisions at sqrt(s)=19, 17 GeV, relevant for the
identification of the QCD phase transition in these collisions, are discussed.
The dependence of open and closed charm yields in Pb+Pb collisions on the
number of participating nucleons (N) indicates non thermal charm production and
J/Psi dissociation, stronger than the absorption seen in any other elementary
hadron. The J/Psi in central Pb+Pb collisions could originate dominantly from c
cbar pair coalescence out of a hadronizing quark and gluon environment.
Furthermore, the J/Psi appears to be suppressed in S+U collisions at sqrt(s)=19
GeV, as opposed to current interpretations. A significant change in the
(J/Psi)/D Dbar ratio as well as in the number density of kaons is observed
above energy density approx. 1 GeV/fm^3, suggesting a change of phase at this
energy density, and underlining the importance of direct open charm
measurements.

</DOC>
<DOC>
<DOCNO> 151901 </DOCNO>
A non-Abelian Chern-Simons term for non-BPS D-branes


  We propose a Chern-Simons term for N coinciding non-BPS D-branes. Demanding
full U(N) invariance and compatibility with T-duality, it is shown that it is
necessary to introduce new interaction terms, through which the non-BPS
D-branes couple to all p-form RR fields.

</DOC>
<DOC>
<DOCNO> 13171 </DOCNO>
Anomalously large critical regions in power-law random matrix ensembles


  We investigate numerically the power-law random matrix ensembles.
Wavefunctions are fractal up to a characteristic length whose logarithm
diverges asymmetrically with different exponents, 1 in the localized phase and
0.5 in the extended phase. The characteristic length is so anomalously large
that for macroscopic samples there exists a finite critical region, in which
this length is larger than the system size. The Green's functions decrease with
distance as a power law with an exponent related to the correlation dimension.

</DOC>
<DOC>
<DOCNO> 119277 </DOCNO>
The Universe behind the Milky Way


  Due to the foreground extinction of the Milky Way, galaxies appear
increasingly fainter the closer they lie to the Galactic Equator, creating a
"zone of avoidance" of about 25% in the distribution of optically visible
galaxies. A "whole-sky" map of galaxies is essential, however, for
understanding the dynamics in our local Universe, in particular the peculiar
velocity of the Local Group with respect to the Cosmic Microwave Background and
velocity flow fields such as in the Great Attractor region. Various dynamically
important structures behind the Milky Way have only recently been made
``visible'' through dedicated deep surveys at various wavelengths. The wide
range of observational searches (optical, near infrared, far infrared, radio
and X-ray) for galaxies in the Zone of Avoidance are reviewed, including a
discussion on the limitations and selection effects of these partly
complementary approaches. The uncovered and suspected large-scale structures
are summarized. Reconstruction methods of the density field in the Zone of
Avoidance are described and the resulting predictions compared with
observational evidence. The comparison between reconstructed density fields and
the observed galaxy distribution allow derivations of the density and biasing
parameters Omega_0 and b.

</DOC>
<DOC>
<DOCNO> 69112 </DOCNO>
MSW effect with flavor changing interactions and the atmospheric


  We consider flavor changing effective neutrino interactions in the context of
massive neutrinos in the issue of atmospheric neutrinos. Assuming as usual that
this is an indication of the oscillation of muon neutrinos into tau neutrinos
we show that there is a set of parameters which is consistent with the MSW
resonance condition for the typical Earth density and atmospheric neutrino
energies. In particular we show that even if the vacuum mixing angle vanishes
it is still possible to have a resonance which is compatible with the
atmospheric neutrino data. We also briefly consider the case of the solar
neutrino problem.

</DOC>
<DOC>
<DOCNO> 120965 </DOCNO>
The M(BH)-Sigma Relation for Supermassive Black Holes


  We investigate the differences in the M(BH)-sigma relation derived recently
by Ferrarese & Merritt (2000) and Gebhardt et al. (2000). The shallower slope
found by the latter authors (3.75 vs. 4.8) is due partly to the use of a
regression algorithm that ignores measurement errors, and partly to the value
of the velocity dispersion adopted for a single galaxy, the Milky Way. A
steeper relation is shown to provide a better fit to black hole masses derived
from reverberation mapping studies. Combining the stellar dynamical, gas
dynamical, and reverberation mapping mass estimates, we derive a best-fit
relation M(BH) = 1.30 (+/- 0.36) X 10^8 (sigma_c/200)^{4.72(+/- 0.36)}, where
M(BH) is in solar masses, and sigma in km/s.

</DOC>
<DOC>
<DOCNO> 117075 </DOCNO>
Relativistic recoil corrections to the atomic energy levels


  The quantum electrodynamic theory of the nuclear recoil effect in atoms to
all orders in \alpha Z and to first order in m/M is considered. The complete
\alpha Z - dependence formulas for the relativistic recoil corrections to the
atomic energy levels are derived in a simple way. The results of numerical
calculations of the recoil effect to all orders in \alpha Z are presented for
hydrogenlike and lithiumlike atoms. These results are compared with analytical
results obtained to lowest orders in \alpha Z. It is shown that even for
hydrogen the numerical calculations to all orders in \alpha Z provide most
precise theoretical predictions for the relativistic recoil correction of first
order in m/M.

</DOC>
<DOC>
<DOCNO> 99271 </DOCNO>
Lattices and Parameter Reduction in Division Algebras


  Let k be an algebraically closed field of characteristic 0 and let D be a
division algebra whose center F contains k. We shall say that D can be reduced
to r parameters if D = D_0 tensor_{F_0} F, where D_0 is a division algebra, the
center F_0 of D_0 contains k and trdeg(F_0/k) = r.
  We show that every division algebra of odd degree n >= 5 can be reduced to at
most (n-1)(n-2)/2 parameters. Moreover, every crossed product division algebra
of degree n >= 4 can be reduced to at most (log_2(n) - 1)n + 1 parameters. Our
proofs of these results rely on lattice-theoretic techniques.

</DOC>
<DOC>
<DOCNO> 72164 </DOCNO>
Scalar Mesons in QCD


  We review the analysis of the quark and gluon substructures of the scalar
mesons from QCD spectral sum rules and some low-energy theorems applied to the
scalar QCD anomaly current. The present data favour equal components of \bar
uu+ \bar dd and of gg in the wave functions of the low-mass (below 1 GeV)
scalar mesons, which make the wide \sigma and the narrow f_0(980) as \eta'-like
particles, which can have strong couplings to meson pairs through OZI
violations. A coherent picture of the other I=0 scalar mesons spectra within
this mixing scheme is shortly discussed. We also expect the a_0(980) to be the
lowest isovector \bar ud state, and the K^*_0(1430) its \bar ds partner.

</DOC>
<DOC>
<DOCNO> 71989 </DOCNO>
Evolution equations for the effective four-quark interactions in QCD


  A nonperturbative renormalization group equation describes how the momentum
dependent four-quark vertex depends on an infrared cutoff. We find a quasilocal
one-particle irreducible piece generated by (anomaly-free) multi-gluon
exchange. It becomes important at a cutoff scale where scalar and pseudoscalar
meson-bound states are expected to play a role. This interaction remains
subleading as compared to the effective one-gluon exchange contribution. The
local instanton induced four-quark interaction becomes dominant at a scale
around 800 MeV. In absence of a gluon mass the strong dependence of the
one-gluon exchange on the transferred momentum indicates that the pointlike
interactions of the Nambu-Jona-Lasinio model cannot give a very accurate
description of QCD. A pointlike effective four-quark interaction becomes more
realistic in case of spontaneous color symmetry breaking.

</DOC>
<DOC>
<DOCNO> 118224 </DOCNO>
On radial gas flows, the Galactic Bar and chemical evolution in the


  We develop a numerical chemical model allowing for radial flows of gas, with
the aim to analyse the possible role of gas flows in the chemical evolution of
the Galactic Disc. The dynamical effects of the Galactic Bar on the radial gas
profile of the Disc are especially addressed.

</DOC>
<DOC>
<DOCNO> 70292 </DOCNO>
Implications of radion-higgs couplings for high energy scattering in the


  In this report we derive the couplings of the Randall-Sundrum radion to the
standard model higgs boson. We then use these couplings to determine the J=0
partial wave amplitude for the process $hh\to h\phi $. We find that at very
high energies (i.e. $s\gg m_h^2, \mp^2$) the s wave partial wave unitarity is
violated if $m_h>m_c\approx \sqrt{16\pi\vphi v}$ where $\vphi$ is the radion
vev. Interestingly this bound is independent of the radion mass to the leading
order. We also consider the high energy behaviour of the transition amplitudes
for some other processes in the RS scenario and compare them with their SM
behaviour.

</DOC>
<DOC>
<DOCNO> 69592 </DOCNO>
Antimatter from supersymmetric dark matter


  We propose low-energy antideuterons in cosmic rays as a new possible
signature for indirect detection of supersymmetric dark matter.
  Since the energy spectrum of the antiproton secondary component is still
spoilt by considerable theoretical uncertainties, looking for low-energy
antideuterons seems a plausible alternative.
  We apply our calculation to the AMS experiment, when mounted on the
International Spatial Station. If a few low-energy antideuterons will be
discovered by AMS, this should be seriously taken as a clue for the existence
of relic, massive neutralinos in the dark halo of our Galaxy.

</DOC>
<DOC>
<DOCNO> 118557 </DOCNO>
Angular size in quintessence cosmology


  We investigate the influence of an exotic fluid component ("quintessence") on
the angular size-redshift relation for distant extragalactic sources.
Particular emphasis is given for the redshif $z_{m}$ at which the angular size
takes its minimal value. We derive an analytical closed form which determines
how $z_m$ depends on the parameter of the equation of state describing the
exotic component. The results for a flat model dominated by a "quintessence"
are compared in detail with the ones for the standard open model dominated by
cold dark matter. Some consequences of systematic evolutionary effects on the
values of $z_{m}$ are also briefly discussed. It is argued that the critical
redshift, for all practical purposes, may completely be removed if such effects
are taken into account.

</DOC>
<DOC>
<DOCNO> 102795 </DOCNO>
Invitation to higher local fields, Part II, section 10: Galois modules


  This is a concise survey of links between Galois module theory and class
field theory (CFT). It explores various uses of CFT in Galois module theory, it
comments on the absence of CFT in contexts where it might be expected to play a
role and indicates some lines of research that might bring CFT to play a more
prominent role in Galois module theory.

</DOC>
<DOC>
<DOCNO> 99547 </DOCNO>
Three Bimodules for Mansfield's Imprimitivity Theorem


  There are at least three imprimitivity bimodules naturally associated to a
maximal coaction of a discrete group G on a C*-algebra and a normal subgroup of
G: Mansfield's bimodule; the bimodule assembled by Ng from Green's
imprimitivity bimodule and Katayama duality; and a bimodule assembled from
Green's bimodule and a crossed-product Mansfield bimodule. We show that all
three of these are isomorphic, so that the corresponding inducing maps on
representations are identical. This can be interpreted as saying that Mansfield
and Green induction are inverses of one another ``modulo Katayama duality''.
These results pass to twisted coactions; dual results starting with an action
are also given.

</DOC>
<DOC>
<DOCNO> 170279 </DOCNO>
Feedback-stabilization of an arbitrary pure state of a two-level atom


  Unit-efficiency homodyne detection of the resonance fluorescence of a
two-level atom collapses the quantum state of the atom to a stochastically
moving point on the Bloch sphere. Recently,Hofmann, Mahler, and Hess [Phys.
Rev. A {\bf 57}, 4877 (1998)] showed that by making part of the coherent
driving proportional to the homodyne photocurrent can stabilize the state to
any point on the bottom half of the sphere. Here we reanalyze their proposal
using the technique of stochastic master equations, allowing their results to
be generalized in two ways. First, we show that any point on the upper or lower
half, but not the equator, of the sphere may be stabilized. Second, we consider
non-unit-efficiency detection, and quantify the effectiveness of the feedback
by calculating the maximal purity obtainable in any particular direction in
Bloch space.

</DOC>
<DOC>
<DOCNO> 99760 </DOCNO>
On the cut and paste property of higher signatures of a closed oriented


  We extend the notion of the symmetric signature $\sigma(\bar{M},r)$ in L^n(R)
for a compact n-dimensional manifold M without boundary, a reference map r from
M to BG and a homomorphism of rings with involutions from ZG to R to the case
with boundary $\partial M$, where $(\bar{M},\bar{\partial M}) \to (M,\partial
M)$ is the G-covering associated to r. We need the assumption that
$C_*(\bar{\partial M}) \otimes_{\zz G} R$ isR-chain homotopy equivalent to a
R-chain complex D_* with trivial m-th differential for n = 2m resp. n = 2m+1.
  Let Z be a closed oriented manifold with reference map BG. Let F be a cutting
codimension one submanifold in Z and let $\bar{F} \to F$ be the associated
$G$-covering. Denote by $\alpha_m(\bar{F})$ the m-th Novikov-Shubin invariant
and by $b_m^{(2)}(\bar{F})$ the m-th L^2-Betti number. We use
$\sigma(\bar{M},r)$ to prove the additivity (or cut and paste property) of the
higher signatures of Z if we have $\alpha_m(\bar{F}) = \infty^+$ in the case n
= 2m and, in the case n = 2m+1, if we have $\alpha_m(\bar{F}) = \infty^+$ and
$b_m^{(2)}(\bar{F}) = 0$. We give examples, where these conditions are not
satisfied and additivity fails. Our work is motivated by the one of
Leichtnam-Lott-Piazza, Lott and Weinberger.

</DOC>
<DOC>
<DOCNO> 10710 </DOCNO>
Characteristic Angles in the Wetting of an Angular Region: Surface Shape


  The shape of a liquid surface bounded by an acute or obtuse planar angular
sector is considered by using classical analysis methods. For acute angular
sectors the two principal curvatures are of the order of the (fixed) mean
curvature. But for obtuse sectors, the principal curvatures both diverge as the
vertex is approached. The power-law divergence becomes stronger with increasing
opening angle. Possible implications of this contrasting behavior are
suggested.

</DOC>
<DOC>
<DOCNO> 84094 </DOCNO>
Towards a Deeper Understanding of General Relativity


  Standard treatments of general relativity accept the gravitational slowing of
clocks as a primary phenomenon, necessitating no further alalysis as to cause.
Rejecting this attitude, it is argued that one or more of the fundamental
"constants" governing the quantum mechanics of atoms must depend upon position
in a gravitational field. A simple relationship governing the possible
dependencies of e, h, c and m is deduced, and arguments in favor of the choice
of the electron rest mass, m, are presented. The reduction of rest mass is thus
taken to be the sole cause of clock slowing. Importantly, this dependency
implies another effect, heretofore unsuspected, namely, the gravitational
elongation of measuring rods. An alternate ("telemetric") system of measurement
is introduced, leading to a metric that is conformally related to the usual
proper metric. In terms of the new system, many otherwise puzzling phenomena
may be simply understood. In particular,the geometry of the Schwarzschild space
as described by the telemetric system differs profoundly from that described by
proper measurments, leading to a very different understanding of the structure
of black holes. The theory is extended to describe the cosmological problem,
leading to a remarkable alternate view of the structure and history of the
universe.

</DOC>
<DOC>
<DOCNO> 151009 </DOCNO>
Symmetry Origin of Infrared Divergence Cancellation in Topologically


  We manifestly verify that the miraculous cancellation of the infrared
divergence of the topologically massive Yang-Mills theory in the Landau gauge
is completely determined by a new vector symmetry existing in its large
topological mass limit, the Chern-Simons theory. Furthermore, we show that the
cancellation theorem proposed by Pisarski and Rao is an inevitable consequence
of this new vector symmetry.

</DOC>
<DOC>
<DOCNO> 84728 </DOCNO>
Dynamics of the formation of an event horizon


  The radial motion of matter in a centrally symmetric gravitational field in a
comoving reference frame is investigated for a realistic equation of state of
matter. The dynamics of the formation of an event horizon are investigated.

</DOC>
<DOC>
<DOCNO> 100478 </DOCNO>
Feynman Equation in Hamiltonian Quantum Field Theory


  Functional Schr\"{o}dinger equations for interacting fields are solved via
rigorous non-perturbative Feynman type integrals.

</DOC>
<DOC>
<DOCNO> 70607 </DOCNO>
Many-Body Coulomb Gauge Exotic and Charmed Hybrids


  Utilizing a QCD Coulomb gauge Hamiltonian with linear confinement specified
by lattice, we report a relativistic many-body calculation for the light exotic
and charmed hybrid mesons. The Hamiltonian successfully describes both quark
and gluon sectors, with vacuum and quasiparticle properties generated by a BCS
transformation and more elaborate TDA and RPA diagonalizations for the meson
($q\bar{q}$) and glueball ($gg$) masses. Hybrids entail a computationally
intense relativistic three quasiparticle ($q\bar{q}g$) calculation with the 9
dimensional Hamiltonian matrix elements evaluated variationally by Monte Carlo
techniques. Our new TDA (RPA) spectrum for the nonexotic $1^{--}$ charmed
($c\bar{c}$ and $c\bar{c}g$) system provides an explanation for the
overpopulation of the observed $J/\psi$ states. For the important $1^{-+}$
light exotic channel we obtain hybrid masses above 2 $GeV$, in broad agreement
with lattice and flux tube models, indicating that the recently observed
resonances at 1.4 and 1.6 $GeV$ are of different, perhaps four quark,
structure.

</DOC>
<DOC>
<DOCNO> 71515 </DOCNO>
Fermions from Bosons in a Theta Vacuum


  This letter is concerned with two monopole effects: the induced charge from a
theta vacuum and the fermions from bosons mechanism. We observe that these
seemingly disparate effects combine together in a natural way at strong
coupling to produce a parity violating spectrum of stable spin-half dyons from
an underlying scalar-gauge theory. The manner in which they do this may have
implications for the dual standard model.

</DOC>
<DOC>
<DOCNO> 12813 </DOCNO>
The universal behavior of one-dimensional, multi-species branching and


  A directed percolation process with two symmetric particle species exhibiting
exclusion in one dimension is investigated numerically. It is shown that if the
species are coupled by branching ($A\to AB$, $B\to BA$) a continuous phase
transition will appear at zero branching rate limit belonging to the same
universality class as that of the dynamical two-offspring (2-BARW2) model. This
class persists even if the branching is biased towards one of the species. If
the two systems are not coupled by branching but hard-core interaction is
allowed only the transition will occur at finite branching rate belonging to
the usual 1+1 dimensional directed percolation class.

</DOC>
<DOC>
<DOCNO> 85233 </DOCNO>
Angular momentum conservation law in Einstein-Cartan space-time


  In the light of the local Lorentz transformations and the general Noether
theorem, a new formulate of the general covariant angular momentum conservation
law in Einstein-Cartan gravitation theory is obtained, which overcomes the
critical difficulty in the other formulates that the conservation law depended
on the coordinative choice.

</DOC>
<DOC>
<DOCNO> 178552 </DOCNO>
Nucleon-nucleon elastic scattering to 3 GeV


  A partial-wave analysis (PWA) of NN elastic scattering data has been
completed. This analysis covers an expanded energy range, from threshold to a
laboratory kinetic energy of 3 GeV, in order to include recent elastic pp
polarized scattering measurements performed at SATURNE II. Results of the
energy-dependent fit are compared with single-energy solutions and Saclay
amplitudes obtained via the direct-reconstruction approach. We also comment on
the status of Eps1 in the low-energy region.

</DOC>
<DOC>
<DOCNO> 8526 </DOCNO>
Geometry, Statistics and Asymptotics of Quantum Pumps


  We give a pedestrian interpretation of a formula of Buttiker et. al. (BPT)
relating the adiabatically pumped current to the S matrix and its (time)
derivatives. We relate the charge in BPT to Berry's phase and the corresponding
Brouwer pumping formula to curvature. As applications we derive explicit
formulas for the joint probability density of pumping and conductance when the
S matrix is uniformly distributed; and derive a new formula that describes hard
pumping when the S matrix is periodic in the driving parameters.

</DOC>
<DOC>
<DOCNO> 10481 </DOCNO>
Metastability and Transient Effects in Vortex Matter Near a Disorder


  We examine metastable and transient effects both above and below the
first-order disorder driven decoupling line in a 3D simulation of magnetically
interacting pancake vortices. We observe pronounced transient and history
effects as well as supercooling and superheating between the ordered and
disordered phases. In the disordered supercooled state as a function of DC
driving, reordering occurs through the formation of growing moving channels of
the ordered phase. We find that hysteresis in V(I) is strongly dependent on the
proximity to the decoupling transition line.

</DOC>
<DOC>
<DOCNO> 13886 </DOCNO>
Twirling Elastica: Kinks, Viscous Drag, and Torsional Stress


  Biological filaments such as DNA or bacterial flagella are typically curved
in their natural states. To elucidate the interplay of viscous drag, twisting,
and bending in the overdamped dynamics of such filaments, we compute the
steady-state torsional stress and shape of a rotating rod with a kink. Drag
deforms the rod, ultimately extending or folding it depending on the kink
angle. For certain kink angles and kink locations, both states are possible at
high rotation rates. The agreement between our macroscopic experiments and the
theory is good, with no adjustable parameters.

</DOC>
<DOC>
<DOCNO> 117383 </DOCNO>
Quantum Astronomy. Part II


  A new method of fundamental quantum data sampling on basis of an optimum
measuring scale has been designed. The method was applied for minimization of
redundant experimental data in different fields of physics. Basing of this
method there has been found the laws of binding electromagnetic, strong and
gravitational interaction. It is shown that the laws of quantizing of physical
quantities are the effect of space fibering. Moreover the said laws have a
general electromagnetic nature as well. They are related to dimensionless
electromagnetic constants - Na =861 and a-1=137,0360547255. These constants
cover both the atomic and the space scales.

</DOC>
<DOC>
<DOCNO> 122741 </DOCNO>
The Merger of a Helium Star and a Black Hole: Gamma-Ray Bursts


  There is growing observational evidence that gamma-ray bursts (GRBs) are
powered by black holes accreting rapidly through a disk. The supernova-like
outburst that accompanies some gamma-ray bursts suggest that some long-duration
GRBs may be driven by the accretion of a rotating stellar core onto a central
black hole. Such a system can be produced when a compact remnant spirals into
the helium core of its binary companion. During the inspiral, orbital angular
momentum is injected into the core. By the time the compact remnant reaches the
center of the helium core, it too has gained angular momentum as well as mass,
producing a rapidly accreting black hole (or neutron star) at the center of a
rotating stellar core. In this paper, we use a 3-dimensional smooth particle
hydrodynamics (SPH) code to follow such a merger process and make quantitative
estimates of the initial mass and spin of the central compact remnant, as well
as the angular momentum in the accreting helium core. From these results, we
estimate GRB explosion energies. In all mergers, magnetically driven jets are
expected to produce GRB explosions with energies above 10^{51} ergs. For
neutrino-annihilation-driven explosions, the GRB energy increases dramatically
with helium star mass: the merger of a 2 M_sun compact remnant with a 4 M_sun
helium star only produces a 10^{47} ergs explosion in \sim 500 s whereas the
merger of a 2 M_sun compact remnant with a 16 M_sun helium star produces a
>10^{52} ergs explosion in \sim 65 s. (Abridged)

</DOC>
<DOC>
<DOCNO> 70428 </DOCNO>
Renormalizaion group equations and infrared quasi fixed point behaviors


  The renormalization group equations(RGEs) of non-universal soft
supersymmetric breaking terms with CP violating phases are analyzed in this
paper. We obtain the analytic solutions of RGEs by directly solving the RGEs
themselves. Compared with the method of spurion expansion our approach proves
to be simple and succinct, and easy to extend to the case of complex
parameters. With the analytical forms of the solutions we obtained the infrared
quasi fixed point behavior of soft terms are analyzed and it turns out to
support the notion in scenarios with CP violating phases.

</DOC>
<DOC>
<DOCNO> 151489 </DOCNO>
Wess Zumino Couplings for Generalized Sigma Orbifold Fixed-points


  The Wess-Zumino couplings for generalized sigma-orbifold fixed-points are
presented and the generalized GS 6-form that encoding the complete
sigma-standard gauge-gravitational-non standard gauge anomaly and its opposite
inflow is derived.

</DOC>
<DOC>
<DOCNO> 120238 </DOCNO>
Parameter Estimation in Astronomy with Poisson-Distributed Data. II. The


  I investigate the use of Pearson's chi-square statistic, the Maximum
Likelihood Ratio statistic for Poisson distributions, and the chi-square-gamma
statistic (Mighell 1999, ApJ, 518, 380) for the determination of the
goodness-of-fit between theoretical models and low-count Poisson-distributed
data. I demonstrate that these statistics should not be used to determine the
goodness-of-fit with data values of 10 or less. I modify the chi-square-gamma
statistic for the purpose of improving its goodness-of-fit performance. I
demonstrate that the modified chi-square-gamma statistic performs (nearly) like
an ideal chi-square statistic for the determination of goodness-of-fit with
low-count data. On average, for correct (true) models, the mean value of
modified chi-square-gamma statistic is equal to the number of degrees of
freedom (nu) and its variance is 2*nu --- like the chi-square distribution for
nu degrees of freedom. Probabilities for modified chi-square-gamma
goodness-of-fit values can be calculated with the incomplete gamma function. I
give a practical demonstration showing how the modified chi-square-gamma
statistic can be used in experimental astrophysics by analyzing simulated X-ray
observations of a weak point source (signal-to-noise ratio of 5.2; 40 photons
spread over 317 pixels) on a noisy background (0.06 photons per pixel).
Accurate estimates (95% confidence intervals/limits) of the location and
intensity of the X-ray point source are determined.

</DOC>
<DOC>
<DOCNO> 8898 </DOCNO>
Do shifting Bragg peaks of cuprate stripes reveal fractionally charged


  The stripe phases found in correlated oxides can be viewed as an ordering of
the solitons associated with doping the Mott-insulating state. Inspired by the
recent observation that the stripes tilt away from the main axis of the crystal
lattice in the regime x = 1/8, we propose that a new type of stripe phase is
realized in the large doping regime. This new phase should be viewed as a doped
version of the microscopically insulating x = 1/8 stripes. The topological
excitations associated with the extra doping are fractionally charged kinks
along the stripes whose motions make the stripe fluctuate. We argue that the
directional degree of freedom of the kinks might order, causing the stripe
phase to tilt. Quantitative predictions follow for the doping dependence of the
tilt angle, which in turn can be used to determine the fundamental charge
quantum associated with the stripe phase.

</DOC>
<DOC>
<DOCNO> 118708 </DOCNO>
Testing the multiple supernovae versus gamma-ray burst scenarios for


  The energy source of the giant HI supershells in nearby galaxies and in our
own is still an unsettled issue. Proposed scenarios for production of
near-complete ringlike supershells are multiple supernovae (SNe) and gamma-ray
bursts (GRBs). In the late phase of evolution it is difficult to tell these
models apart. We show that, if a supershell has been powered by multiple SNe,
peculiar metal abundances should be found in the medium within the bubble. We
present line diagnostics that could detect such unusual abundances, such as
unusually high ratios of [O]/[Fe] and [Ne]/[Fe]. Among ions of the same
element, a higher enhancement is expected in lines from a high-ionization state
than in lines from a low-ionization state. Identification of the energy source
of HI supershells would set strong constraints on the rates and energetics of
GRBs, as well as on their location within a galaxy.

</DOC>
<DOC>
<DOCNO> 169899 </DOCNO>
Teleportation using coupled oscillator states


  We analyse the fidelity of teleportation protocols, as a function of resource
entanglement, for three kinds of two mode oscillator states: states with fixed
total photon number, number states entangled at a beam splitter, and the
two-mode squeezed vacuum state. We define corresponding teleportation protocols
for each case including phase noise to model degraded entanglement of each
resource.

</DOC>
<DOC>
<DOCNO> 120111 </DOCNO>
Essentials of k-essence


  We recently introduced the concept of "k-essence" as a dynamical solution for
explaining naturally why the universe has entered an epoch of accelerated
expansion at a late stage of its evolution. The solution avoids fine-tuning of
parameters and anthropic arguments. Instead, k-essence is based on the idea of
a dynamical attractor solution which causes it to act as a cosmological
constant only at the onset of matter-domination. Consequently, k-essence
overtakes the matter density and induces cosmic acceleration at about the
present epoch. In this paper, we present the basic theory of k-essence and
dynamical attractors based on evolving scalar fields with non-linear kinetic
energy terms in the action. We present guidelines for constructing concrete
examples and show that there are two classes of solutions, one in which cosmic
acceleration continues forever and one in which the acceleration has finite
duration.

</DOC>
<DOC>
<DOCNO> 152180 </DOCNO>
Renormalization Group Analysis of Tachyon Condensation


  Renormalization group analysis of boundary conformal field theory on bosonic
D25-brane is used to study tachyon condensation. Placing the lump on a finite
circle and triggering only the first three tachyon modes, the theory flows to
nearby IR fixed point representing lumps that are extended object with definite
profile. The boundary entropy corresponding to the D24-brane tension is
calculated in the leading order in perturbative analysis which decreases under
RG flow and agrees with the expected result to an accuracy of 8%. Multicritical
behaviour of the IR theory suggests that the end point of the flow represents a
configuration of two D24-branes. Analogy with Kondo physics is discussed.

</DOC>
<DOC>
<DOCNO> 170122 </DOCNO>
Relational Quantum Measurements, Information and State Collapse


  The quantum measurement problem considered for measuring system (MS) consist
of measured state S (particle), detector D and information processing device
(observer) O. It's shown that O states selfreference structure results in
principal nonobservability of MS interference terms which discriminate pure and
mixed S states. Such observables restriction permit to construct for MS states
subjective representation (SR) which describes probabilistic evolution for
measurement events observed by $O$ and his subjective information about S
values. SR is dual and nonequivalent to MS Hilbert space $H$ for external
observer $O'$. Due to it SR evolution is compatible with Schrodinger linear MS
evolution observed by $O'$. It's argued that SR evolution corresponds to S
state collapse for individual events observed by $O$.

</DOC>
<DOC>
<DOCNO> 8597 </DOCNO>
Fluctuations in mixtures of lamellar- and nonlamellar-forming lipids


  We consider the role of nonlamellar-forming lipids in biological membranes by
examining fluctuations, within the random phase approximation, of a model
mixture of two lipids, one of which forms lamellar phases while the other forms
inverted hexagonal phases. To determine the extent to which nonlamellar-forming
lipids facilitiate the formation of nonlamellar structures in lipid mixtures,
we examine the fluctuation modes and various correlation functions in the
lamellar phase of the mixture. To highlight the role fluctuations can play, we
focus on the lamellar phase near its limit of stability. Our results indicate
that in the initial stages of the transition, undulations appear in the
lamellae occupied by the tails, and that the nonlamellar-forming lipid
dominates these undulations. The lamellae occupied by the head groups pinch off
to make the tubes of the hexagonal phase. Examination of different correlations
and susceptibilities makes quantitative the dominant role of the
nonlamellar-forming lipids.

</DOC>
<DOC>
<DOCNO> 69860 </DOCNO>
Detection of weakly interacting light vector bosons by coherent


  We propose a novel experimental method to produce and detect weakly
interacting light vector bosons using coherent processes in refractive media. A
light vector boson would be produced by a laser photon scattered at a plane
interface between two media of different dielectric properties and will be
converted back to photon in the similar scattering process. The effect depends
strongly on the indices of refraction of the two media. If incident and
recovered photons were traveling through extremely high vacuums, limits on the
existence of several light vector bosons could be substantially improved.

</DOC>
<DOC>
<DOCNO> 152150 </DOCNO>
Invariances of regularized QED diagrams


  We consider properties of connected diagrams with fermion-photon interaction
and such fermion and photon propagators and vertex function that the values of
these diagrams are finite. We establish the properties of these propagators and
vertex function that imply that these diagrams are invariant under C, P, T, CP,
CT, PT, or CPT transformations up to some phase factor common to each process.
We introduce eight new transformations related to Hermiticity and establish the
conditions under which they leave the tree transition probabilities invariant.
We determine such general Lorentz form-invariant fermion and photon propagators
and fermion-photon vertex functions that make diagrams Lorentz-invariant.

</DOC>
<DOC>
<DOCNO> 83068 </DOCNO>
Take-home Complexity


  We discuss the use of projects in first-year graduate complexity theory
courses.

</DOC>
<DOC>
<DOCNO> 101249 </DOCNO>
Generalized KP Hierarchy for Several Variables


  Following the techniques of M. Sato (see \cite{Sa}), a generalization of the
KP hierarchy for more than one variable is proposed. An approach to the
classification of solutions and a method to construct algebraic solutions is
also offered.

</DOC>
<DOC>
<DOCNO> 116268 </DOCNO>
Superluminal Near-field Dipole Electromagnetic Fields


  The purpose of this paper is to present mathematical evidence that
electromagnetic near-field waves and wave groups, generated by an oscillating
electric dipole, propagate much faster than the speed of light as they are
generated near the source, and reduce to the speed of light at about one
wavelength from the source. The speed at which wave groups propagate (group
speed) is shown to be the speed at which both modulated wave information and
wave energy density propagate. Because of the similarity of the governing
partial differential equations, two other physical systems (magnetic
oscillating dipole, and gravitational radiating oscillating mass) are noted to
have similar results.

</DOC>
<DOC>
<DOCNO> 67956 </DOCNO>
Calculation of the Electron Self Energy for Low Nuclear Charge


  We present a nonperturbative numerical evaluation of the one-photon electron
self energy for hydrogenlike ions with low nuclear charge numbers Z=1 to 5. Our
calculation for the 1S state has a numerical uncertainty of 0.8 Hz for hydrogen
and 13 Hz for singly-ionized helium. Resummation and convergence acceleration
techniques that reduce the computer time by about three orders of magnitude
were employed in the calculation. The numerical results are compared to results
based on known terms in the expansion of the self energy in powers of (Z
alpha).

</DOC>
<DOC>
<DOCNO> 122187 </DOCNO>
Exploring the Multi-Wavelength, Low Surface Brightness Universe


  Our current understanding of the low surface brightness universe is quite
incomplete, not only in the optical, but also in other wavelength regimes. As a
demonstration of the type of science which is facilitated by a virtual
observatory, we have undertaken a project utilizing both images and catalogs to
explore the multi-wavelength, low surface brightness universe. Here, we present
some initial results of this project. Our techniques are complimentary to
normal data reduction pipeline techniques in that we focus on the diffuse
emission that is ignored or removed by more traditional algorithms. This
requires a spatial filtering which must account for objects of interest, in
addition to observational artifacts (e.g., bright stellar halos). With this
work we are exploring the intersection of the catalog and image domains in
order to maximize the scientific information we can extract from the federation
of large survey data.

</DOC>
<DOC>
<DOCNO> 122302 </DOCNO>
An XMM-Newton study of the sub-structure in M87's halo


  The high signal to noise and good point spread function of XMM have allowed
the first detailed study of the interaction between the thermal and radio
emitting plasma in the central regions of M87. We show that the X-ray emitting
structure, previously seen by ROSAT, is thermal in nature and that the east and
southwest extensions in M87's X-ray halo have a significantly lower temperature
(kT= 1.5 keV) than the surrounding ambient medium (kT= 2.3 keV). There is
little or no evidence for non-thermal emission with an upper limit on the
contribution of a power law component of spectral index flatter than 3 being
less than 1% of the flux in the region of the radio lobes.

</DOC>
<DOC>
<DOCNO> 84101 </DOCNO>
A power filter for the detection of burst sources of gravitational


  We present a filter for detecting gravitational wave signals from burst
sources. This filter requires only minimal advance knowledge of the expected
signal: i.e. the signal's frequency band and time duration. It consists of a
threshold on the total power in the data stream in the specified signal band
during the specified time. This filter is optimal (in the Neyman-Pearson sense)
for signal searches where only this minimal information is available.

</DOC>
<DOC>
<DOCNO> 170689 </DOCNO>
Searching with Quantum Computers


  This article introduces quantum computation by analogy with probabilistic
computation. A basic description of the quantum search algorithm is given by
representing the algorithm as a C program in a novel way.

</DOC>
<DOC>
<DOCNO> 121996 </DOCNO>
Constraining non standard recombination: A worked example


  We fit the BOOMERANG, MAXIMA and COBE/DMR measurements of the cosmic
microwave background anisotropy in spatially flat cosmological models where
departures from standard recombination of the primeval plasma are parametrized
through a change in the fine structure constant $\alpha$ compared to its
present value. In addition to $\alpha$ we vary the baryon and dark matter
densities, the spectral index of scalar fluctuations, and the Hubble constant.
Within the class of models considered, the lack of a prominent second acoustic
peak in the measured spectrum can be accomodated either by a relatively large
baryon density, by a tilt towards the red in the spectrum of density
fluctuations, or by a delay in the time at which neutral hydrogen formed. The
ratio between the second and first peak decreases by around 25% either if the
baryon density $\Omega_bh^2$ is increased or the spectral index $n$ decreased
by a comparable amount, or if neutral hydrogen formed at a redshift $z_*$ about
15% smaller than its standard value. We find that the present data is best
fitted by a delay in recombination, with a lower baryon density than the best
fit if recombination is standard. Our best fit model has $z_*= 900$,
$\Omega_bh^2=0.024$, $\Omega_mh^2=0.14$, $H_0=49$ and $n=1.02$. Compatible with
present data at 95% confidence level $780< z_*<1150$,
$0.018<\Omega_bh^2<0.036$, $0.07< \Omega_m h^2 < 0.3$ and $0.9<n<1.2$.

</DOC>
<DOC>
<DOCNO> 40054 </DOCNO>
Measurement of the Top Quark Mass with the Collider Detector at Fermilab


  This report describes a measurement of the top quark mass in $\ppbar$
collisions at a center of mass energy of 1.8 TeV. The data sample was collected
with the CDF detector during the 1992--95 collider run at the Fermilab
Tevatron, and corresponds to an integrated luminosity of 106 \pb. Candidate
$t\bar{t}$ events in the ``lepton+jets'' decay channel provide our most precise
measurement of the top quark mass. For each event a top mass is determined by
using energy and momentum constraints on the production of the $\ttbar$ pair
and its subsequent decay. A likelihood fit to the distribution of reconstructed
masses in the data sample gives a top mass in the lepton+jets channel of
$176.1\pm 5.1 (stat.)\pm 5.3 (syst.) \gevcc$. Combining this result with
measurements from the ``all-hadronic'' and ``dilepton'' decay topologies yields
a top mass of $176.1\pm 6.6 \gevcc$.

</DOC>
<DOC>
<DOCNO> 40485 </DOCNO>
B lifetime measurements with exclusively reconstructed B decays


  Data collected with the BABAR detector at the PEP-II asymmetric B Factory at
SLAC are used to study the lifetime of the B0 and B+ mesons. The data sample
consists of 7.4 fb-1 collected near the Y(4S) resonance. B0 and B+ mesons are
fully reconstructed in several exclusive hadronic decay modes to charm and
charmonium final states. The B lifetime are determined from the flight length
difference between the two B mesons. The preliminary measurements of the
lifetimes are tau_{B0} = 1.506 +/- 0.052 (stat) +/- 0.029 (syst) ps tau_{B+} =
1.602 +/- 0.049 (stat) +/- 0.035 (syst) ps and of their ratio is
tau_{B+}/tau_{B0} = 1.065 +/- 0.044 (stat) +/- 0.021 (syst).

</DOC>
<DOC>
<DOCNO> 70553 </DOCNO>
U-Spin Symmetry in Charmless B Decays


  We prove a general theorem about equal CP rate differences within pairs of
U-spin related charmless $B$ and $B_s$ decays. Large deviations from equalities
would be evidence for new physics. Six pairs of decays into two pseudoscalar
mesons are identified where such relations hold. Ratios of corresponding rate
differences and certain ratios of rates measure U-spin breaking. These
processes provide useful information on the weak phase $\gamma={\rm Arg}
V^*_{ub}$. Applications of U-spin symmetry to other decays are discussed.

</DOC>
<DOC>
<DOCNO> 122115 </DOCNO>
Properties of post-AGB stars with IRAS colors typical of planetary


  We have investigated the infrared properties of a sample of objects with IRAS
colors typical of planetary nebulae. The selected objects have not yet evolved
to the planetary nebula stage since they have no detectable radio continuum
emission and they are therefore likely post-AGB stars.

</DOC>
<DOC>
<DOCNO> 101489 </DOCNO>
Pathwise description of dynamic pitchfork bifurcations with additive


  The slow drift (with speed $\eps$) of a parameter through a pitchfork
bifurcation point, known as the dynamic pitchfork bifurcation, is characterized
by a significant delay of the transition from the unstable to the stable state.
We describe the effect of an additive noise, of intensity $\sigma$, by giving
precise estimates on the behaviour of the individual paths. We show that until
time $\sqrt\eps$ after the bifurcation, the paths are concentrated in a region
of size $\sigma/\eps^{1/4}$ around the bifurcating equilibrium. With high
probability, they leave a neighbourhood of this equilibrium during a time
interval $[\sqrt\eps, c\sqrt{\eps\abs{\log\sigma}}]$, after which they are
likely to stay close to the corresponding deterministic solution. We derive
exponentially small upper bounds for the probability of the sets of exceptional
paths, with explicit values for the exponents.

</DOC>
<DOC>
<DOCNO> 122047 </DOCNO>
In the Beginning: The First Sources of Light and the Reionization of the


  The formation of the first stars and quasars marks the transformation of the
universe from its smooth initial state to its clumpy current state. In popular
cosmological models, the first sources of light began to form at redshift 30
and reionized most of the hydrogen in the universe by redshift 7. Current
observations are at the threshold of probing the hydrogen reionization epoch.
The study of high-redshift sources is likely to attract major attention in
observational and theoretical cosmology over the next decade.

</DOC>
<DOC>
<DOCNO> 8354 </DOCNO>
Time inhomogeneous Fokker-Plank equation for wave distributions in the


  The time and size distribution of the waves of topplings in the Abelian
sandpile model are expressed as the first arrival at the origin distribution
for a scale invariant, time inhomogeneous Fokker-Planck equation. Assuming a
linear conjecture for the the time inhomogeneity exponent as function of loop
erased random walk (LERW) critical exponent, suggested by numerical results,
this approach allows to estimate the lower critical dimension of the model and
the exact value of the critical exponent for LERW in three dimension. The
avalanche size distribution in two dimensions is found to be the difference
between two closed power laws.

</DOC>
<DOC>
<DOCNO> 122299 </DOCNO>
Current status of Asteroseismology


  Oscillation frequencies are the most accurate properties one can measure for
a star, potentially allowing detailed tests of stellar models and evolution
theories. We briefly review asteroseismology for two classes of stars. In delta
Scuti variables, the main problems are the identification of the observed modes
and the theoretical treatment of rotation. In solar-like stars the main
difficulty is the tiny amplitudes, but credible detections are now being made.
These confirm that stars are oscillating at the approximately the expected
levels, but suggest that amplitudes scale as 1/g rather than L/M. We also
stress the importance of multi-site campaigns. Several space missions will be
launched over the coming years, promising an exciting future for
asteroseismology.

</DOC>
<DOC>
<DOCNO> 117561 </DOCNO>
The Chandrasekhar limit for quark stars


  The Chandrasekhar limit for quark stars is evaluated from simple energy
balance relations, as proposed by Landau for white dwarfs or neutron stars. It
has been found that the limit for quark stars depends on, in addition to the
fundamental constants, the Bag constant.

</DOC>
<DOC>
<DOCNO> 10375 </DOCNO>
On Electric Fields in Low Temperature Superconductors


  The manifestly Lorentz covariant Landau-Ginzburg equations coupled to
Maxwell's equations are considered as a possible framework for the effective
description of the interactions between low temperature superconductors and
magnetic as well as electric fields. A specific experimental set-up, involving
a nanoscopic superconductor and only static applied fields whose geometry is
crucial however, is described, which should allow to confirm or invalidate the
covariant model through the determination of the temperature dependency of the
critical magnetic-electric field phase diagram and the identification of some
distinctive features it should display.

</DOC>
<DOC>
<DOCNO> 8581 </DOCNO>
Folding transitions of the square--diagonal two--dimensional lattice


  The phase diagram of a vertex model introduced by P. Di Francesco (Nucl.
Phys. B 525, 507 1998) representing the configurations of a square lattice
which can fold with different bending energies along the main axes and the
diagonals has been studied by Cluster Variation Method. A very rich structure
with partially and completely folded phases, different disordered phases and a
flat phase is found. The crumpling transition between a disordered and the flat
phase is first-order. The CVM results are confimed by the analysis of the
ground states and of the two limits where the model reduces to an Ising model.

</DOC>
<DOC>
<DOCNO> 67736 </DOCNO>
Cosmological Constraints on the MSSM


  I discuss recent developments in the study of cosmological limits on the
Minimal Supersymmetric Standard Model (MSSM). In particular, I focus on the
effect of neutralino-stau coannihilation on the relic abundance of neutralinos,
and I give examples where the cosmologically derived limits on the
supersymmetric parameters are relaxed, and one example (CP violating phases)
where they are not.

</DOC>
<DOC>
<DOCNO> 70679 </DOCNO>
Enhancement of the Higgs pair production at LHC; the MSSM and extra


  The neutral Higgs pair production at the LHC is studied in the MSSM, the
large extra dimensional (ADD) model and the Randall-Sundrum (RS) model, where
the total cross section can be significantly enhanced compared to that in the
SM. The $p_{_T}$, invariant mass and rapidity distributions of each model have
been shown to be distinctive: The ADD model raises the $p_T$ and invariant mass
distributions at high scales of $p_T$ and invariant mass; in the RS model
resonant peaks appear after the SM contribution dies away; the SM and the MSSM
distributions drop rapidly at those high scales; in the ADD and the RS models
the rapidity distributions congregate more around the center. It is concluded
that various distributions of the Higgs pair production at the LHC with
restrictive kinematic cuts would provide one of the most robust signals for the
extra dimensional effects.

</DOC>
<DOC>
<DOCNO> 8859 </DOCNO>
Cyclotron effective masses in layered metals


  Many layered metals such as quasi-two-dimensional organic molecular crystals
show properties consistent with a Fermi liquid description at low temperatures.
The effective masses extracted from the temperature dependence of the magnetic
oscillations observed in these materials are in the range, m^*_c/m_e \sim 1-7,
suggesting that these systems are strongly correlated. However, the ratio
m^*_c/m_e contains both the renormalization due to the electron-electron
interaction and the periodic potential of the lattice. We show that for any
quasi-two-dimensional band structure, the cyclotron mass is proportional to the
density of states at the Fermi energy. Due to Luttinger's theorem, this result
is also valid in the presence of interactions. We then evaluate m_c for several
model band structures for the \beta, \kappa, and \theta families of
(BEDT-TTF)_2X, where BEDT-TTF is bis-(ethylenedithia-tetrathiafulvalene) and X
is an anion. We find that for \kappa-(BEDT-TTF)_2X, the cyclotron mass of the
\beta-orbit, m^{*\beta}_c, is close to 2 m^{*\alpha}_c, where m^{*\alpha}_c is
the effective mass of the \alpha- orbit. This result is fairly insensitive to
the band structure details. For a wide range of materials we compare values of
the cyclotron mass deduced from band structure calculations to values deduced
from measurements of magnetic oscillations and the specific heat coefficient.

</DOC>
<DOC>
<DOCNO> 117730 </DOCNO>
Screw Instability and Blandford-Znajek Mechanism


  When magnetic field lines thread a rotating black hole's horizon and connect
with remote astrophysical loads, the rotational energy of the black hole can be
extracted through the Blandford-Znajek mechanism. Due to the rotation of the
black hole, the magnetic field lines are twisted and toroidal components are
generated. So poloidal electric currents are induced and the black hole's
rotational energy is transported to the astrophysical loads through Poynting
flux. The Blandford-Znajek mechanism has been considered to be a possible
process for powering extragalactic jets.
  In this paper we show that due to the screw instability of magnetic field,
the toroidal components of the magnetic field, and thus the poloidal currents,
cannot exceed the limits given by the Kruskal-Shafranov criterion. This
significantly lowers the power of the Blandford-Znajek mechanism when the loads
are far from the black hole. So the Blandford-Znajek mechanism can only work
efficiently within the neighborhood of the black hole. The implications of the
results for the scenario of extragalactic jets powered by the Blandford-Znajek
mechanism are discussed.

</DOC>
<DOC>
<DOCNO> 69254 </DOCNO>
CPT-odd Resonances in Neutrino Oscillations


  We consider the consequences for future neutrino factory experiments of small
CPT-odd interactions in neutrino oscillations. The \nu_\mu\to\nu_\mu and
\bar\nu_\mu\to\bar\nu_\mu survival probabilities at a baseline L=732 km can
test for CPT-odd contributions at orders of magnitude better sensitivity than
present limits. Interference between the CPT-violating interaction and CPT-even
mass terms in the Lagrangian can lead to a resonant enhancement of the
oscillation amplitude. For oscillations in matter, a simultaneous enhancement
of both neutrino and antineutrino oscillation amplitudes is possible.

</DOC>
<DOC>
<DOCNO> 119877 </DOCNO>
X-Ray Observation of the L1157 Dark Cloud Region with ASCA


  ASCA observation of a region containing a Class 0 protostar, IRAS 20386+6751
in the L1157 dark cloud, has been carried out. The protostar was not detected,
and the 95% upper limit to the luminosity depends on assumed Nh : Lx(0.5-10
keV) < 1.1e31 erg/s for Nh = 1e23 cm^-2. A Class I protostar in L1152, IRAS
20353+6742, in the same field was also undetected with the upper limit about
three times as much as the L1157 level. Besides these non detections, nine new
X-ray sources were detected and spectral analysis was performed for 4 sources.
One object (AXJ 2038+6801) shows a hard spectrum with a temperature kT = 8 keV
or a power-law photon index = 2.0 and absorbed with Nh = 2e22 cm^-2. Another
fainter one (AXJ 2036+6800) has a soft spectrum with most of the emission
falling below 2 keV. We examine possible nature of these new X-ray sources
based on their spectral properties.

</DOC>
<DOC>
<DOCNO> 120282 </DOCNO>
X-ray emission from the galactic center region Supernova Remnant


  We report the results of a BeppoSAX observation of the composite supernova
remnant G0.9+0.1, located in the Galactic Center region. This new observation,
in which the core of G0.9+0.1 is observed on-axis, confirms our previous
results obtained from a pointing in which the supernova remnant was
serendipitously observed at a large off-axis angle. The better quality of the
new data allows us to confirm the non-thermal nature of the X-ray source
coincident with the central plerion, to significantly improve the estimate of
its spectral parameters, to put more stringent upper limits on the presence of
coherent pulsations (in the range of periods from 4ms to ~ 4\times10^4 s), to
obtain marginal evidence of the possible extended nature of the X-ray plerion
and to put a better upper limit on the 2--10 keV X-ray emission from the 8'
diameter radio shell (L$_{\rm S}<3.4\times 10^{34} {\rm d}_{10}^{2}$ erg
s^{-1}). The X-ray spectrum is best fit with a power-law model with a photon
index \Gamma ~ 2, N_{\rm H} ~ 10^{23} \hcm and a 2-10 keV luminosity of
7.5\times 10^{34} {\rm d}_{10}^{2} erg s^{-1}. The broad band (radio-X-ray)
properties of the composite supernova remnant G0.9+0.1 are indicative of the
likely presence of a young (~ 2,700 yr) neutron star in its central radio core.

</DOC>
<DOC>
<DOCNO> 13787 </DOCNO>
Two-dimensional topological solitons in small exchange-dominated


  A general approach allowing to construct the magnetization distributions of
arbitrary topological charge in small exchange-dominated cylindrical
ferromagnetic particles is presented. The exchange energy functional is
minimized by these distributions exactly. The magnetostatic energy is accounted
partially, so that it facilitates a choice between the topologically equivalent
exchange-only solutions. The resulting magnetization distributions can be
easily generalized to a variety of non-circular cylindrical shapes by means of
a conformal transformation. As an example a magnetic structures of a thin
circular ferromagnetic cylinder both with centered and displaced magnetic
vortex and of a finite Bloch domain wall in an elongated particle is given.

</DOC>
<DOC>
<DOCNO> 117426 </DOCNO>
RR Lyrae Variables in the Globular Cluster M5


  We present V-band CCD photometry of 65 RR Lyr variables from the globular
cluster M5. We have estimated the basic physical parameters for 16 RRc stars
and 26 RRab stars using a Fourier decomposition of the light curves of the
variables. The mean values of mass, luminosity, effective temperature and
relative helium abundance for the RRc stars are measured to be ${\cal
M}=0.54{\cal M}_\odot$, log L = 1.69 T_{eff}=7353 K and Y=0.28, respectively.
For the RRab variables the derived mean values of absolute magnitude,
metallicity and effective temperature are: M_V=0.81, [Fe/H]=-1.23 and
T_{eff}=6465 K. We find that the V amplitude of an RRab star for a given period
is a function of metal abundance rather than Oosterhoff type. We find
significant problems with the calibration of both the zero point and the scale
of the luminosities measured with the Fourier technique. The apparent distance
modulus derived from RRc stars is equal to $14.47\pm0.11$ and it is in good
agreement with recent determinations. On the other hand distance modulus
obtained from the sample of RRab stars (calibrated by the Baade-Wesselink
observations of field RR Lyr variables) is significantly smaller and equal to
$14.27\pm0.04$

</DOC>
<DOC>
<DOCNO> 119558 </DOCNO>
Multi-wavelength visibility measurements of the red giant R Doradus


  We present visibility measurements of the nearby Mira-like star R Doradus
taken over a wide range of wavelengths (650--990 nm). The observations were
made using MAPPIT (Masked APerture-Plane Interference Telescope), an
interferometer operating at the 3.9-m Anglo-Australian Telescope. We used a
slit to mask the telescope aperture and prism to disperse the interference
pattern in wavelength. We observed in R Dor strong decreases in visibility
within the TiO absorption bands. The results are in general agreement with
theory but differ in detail, suggesting that further work is needed to refine
the theoretical models.

</DOC>
<DOC>
<DOCNO> 10445 </DOCNO>
An EPMC study of ZnCl2 melt


  The partial structure factors (PSF) of molten ZnCl2 are known since 1981 due
to the neutron diffraction experiments by Biggin and Enderby. It is shown in
this article that the set of PSF derived from this experiment is not consistent
with new XRD data with much better statistical accuracy. A new set of PSF is
derived which corrects this deficiency. The first diffraction peak is not
dominated by the cation-cation-PSF and the set of PSF shows a remarkable
similarity to the PSF of glassy GeO2 and SiO2 determined recently. The
Levesque, Weis, Reatto potential inversion scheme has been used to interpret
the PSF in terms of three dimensional structures. The thus derived angular
correlations between near neighbor atoms show similarities with CuBr melt,
reflecting the fact that both melts are based on tetrahedral structural units
but also characteristic differences in the +-+ (ZnClZn) angle distribution, the
angle joining adjacent tetrahedra. Further, a plausibility for the enhanced
electrical conductivity of ZnCl2 at higher pressures is given, based on
simulations with the equilibrated potential.

</DOC>
<DOC>
<DOCNO> 118531 </DOCNO>
Star Clusters and the Duration of Starbursts


  The duration of starbursts is important for determining how they are
regulated and the impact they have on their environment. Starbursts contain
numerous prominent star clusters which typically comprise in total ~20% of the
ultraviolet light, embedded in a diffuse glow of recently formed stars
responsible for the dominant ~80%. Hubble Space Telescope images have been
obtained for four starburst galaxies in order to determine their burst duration
from the ages of their star clusters. Preliminary results for NGC3310 are
reported here. The UBI colors of its clusters and diffuse light give consistent
results. The clusters have a broad range of colors, consistent with a
population of instantaneous bursts with ages ranging from 0 to a few 100 Myr.
The diffuse light has a narrow range of color consistent with continuous star
formation over timescales ranging from ~ 10 to 100 Myr. Hence NGC3310's
starburst has lasted ~100 Myr, or about 10 times the crossing time. Other
results noted in the literature also indicate bursts lasting several times
longer than the crossing time. These results suggest that starbursts are not
self-extinguishing flashes. Rather they are sustainable, perhaps
self-regulated.

</DOC>
<DOC>
<DOCNO> 40335 </DOCNO>
Power correction analyses in e+e- annihilation


  The current status of theoretical work and experimental analyses on power
corrections in QCD for e+e- annihilation will be reviewed. Measurements of the
number of active quark flavours n_f and the QCD colour factors C_A and C_F
derived from QCD fits to event shape distributions at lower energies and LEP
energies will be presented. The fits are based on O(alpha_s^2)+NLLA QCD
predictions with power corrections to model hadronisation.

</DOC>
<DOC>
<DOCNO> 70228 </DOCNO>
Some higher moments of deep inelastic structure functions at


  We present the analytic next-to-next-to-leading QCD calculation of some
higher moments of deep inelastic structure functions in the leading twist
approximation. We give results for the moments $N$=1,3,5,7,9,11,13 of the
structure function $F_3$. Similarly we present the moments $N$=10,12 for the
flavour singlet and $N$=12,14 for the non-singlet structure functions $F_2$ and
$F_L$. We have calculated both the three-loop anomalous dimensions of the
corresponding operators and the three-loop coefficient functions of the moments
of these structure functions.

</DOC>
<DOC>
<DOCNO> 40298 </DOCNO>
Improved Measurement of the Positive Muon Anomalous Magnetic Moment


  A new measurement of the positive muon's anomalous magnetic moment has been
made at the Brookhaven Alternating Gradient Synchrotron using the direct
injection of polarized muons into the superferric storage ring. The angular
frequency difference omega_{a} between the angular spin precession frequency
omega_{s} and the angular orbital frequency omega_{c} is measured as well as
the free proton NMR frequency omega_{p}. These determine
  R = omega_{a} / omega_{p} = 3.707~201(19) times 10^{-3}. With mu_{mu} /
mu_{p} = 3.183~345~39(10) this gives a_{mu^+} = 11~659~191(59) times 10^{-10}
(pm 5 ppm), in good agreement with the previous CERN and BNL measurements for
mu^+ and mu^-, and with the standard model prediction.

</DOC>
<DOC>
<DOCNO> 68871 </DOCNO>
Neutrino Oscillations and Cosmology


  Phenomenology of neutrino oscillations in vacuum and in cosmological plasma
is considered. Neutrino oscillations in vacuum are usually described in plane
wave approximation. In this formalism there is an ambiguity if one should
assume $\delta p =0$ and correspondingly $\delta E\neq 0$ or vice versa $\delta
E =0$ and $\delta p \neq 0$, or some other condition. We will use the standard
set of quantum field theory rules and show that the theoretical description is
unambiguous and that the state of oscillating neutrinos is determined by the
conditions of their registration. The wave packet formalism is a natural result
of such an approach. Oscillating neutrinos in cosmological plasma cannot be
described in terms of wave function because of a fast loss of coherence due to
elastic or inelastic scattering, so that one should use the density matrix
formalism. Kinetic equations for the density matrix of oscillating neutrinos
are derived. Numerical and semi-analytical solutions of the equations are
examined. In particular, a possibility of amplification of cosmological lepton
asymmetry in the sector of active neutrinos mixed to sterile ones is critically
discussed.

</DOC>
<DOC>
<DOCNO> 9113 </DOCNO>
Decoherence in Two Bose-Einstein Condensates


  In this paper, decoherence in a system consisting of two Bose-Einstein
condensates is investigated analytically.
 It is indicated that decoherence can be controlled through manipulating the
interaction between the system and environment.
 The influence of the decoherence on quantum coherent atomic tunneling (AT)
between two condensates with arbitrary initial states is studied in detail.
Analytic expressions of the population difference (PD) and the AT current
between two condensates are found. It is shown that the decoherence leads to
the decay of the PD and the suppression of the AT current.

</DOC>
<DOC>
<DOCNO> 121084 </DOCNO>
Clusters AgeS Experiment. Hot subdwarfs and luminous white dwarf


  We present UBV color magnitude diagrams (CMDs) for the M4 globular cluster.
The CMDs show a sequence of four luminous blue stars (V<20, U-V<0.02), which
are good candidates for the cluster hot subdwarfs. These stars could form a
vertical extended horizontal branch (EHB), not reported in previous studies. We
also note the presence of a population of faint blue objects, likely to be hot,
young white dwarfs (WDs) belonging to the cluster. We have selected five
objects above V=22 mag, bright enough for follow-up ground-based spectroscopy
and present their coordinates and finding charts. We show a spectrum for
variable V46 (Kaluzny et al. 1997) which suggests that it is a hot subdwarf,
along with a new light curve obtained with the ISIS image subtraction package
(Alard 2000). Two new variables have been discovered, both lying on the cluster
red giant branch (RGB). We also present a fiducial sequence for the main
sequence, subgiant branch and red giant branch on the V/B-V CMD for a selected
region of M4 with uniform reddening.

</DOC>
<DOC>
<DOCNO> 67889 </DOCNO>
Gravitational Properties of Monopole Spacetimes Near the Black Hole


  Although nonsingular spacetimes and those containing black holes are
qualitatively quite different, there are continuous families of configurations
that connect the two. In this paper we use self-gravitating monopole solutions
as tools for investigating the transition between these two types of
spacetimes. We show how causally distinct regions emerge as the black hole
limit is achieved, even though the measurements made by an external observer
vary continuously. We find that near-critical solutions have a naturally
defined entropy, despite the absence of a true horizon, and that this has a
clear connection with the Hawking-Bekenstein entropy. We find that certain
classes of near-critical solutions display naked black hole behavior, although
they are not truly black holes at all. Finally, we present a numerical
simulation illustrating how an incident pulse of matter can induce the
dynamical collapse of a monopole into an extremal black hole. We discuss the
implications of this process for the third law of black hole thermodynamics.

</DOC>
<DOC>
<DOCNO> 8172 </DOCNO>
Metal induced gap states and Schottky barrier heights at non-reactive


  We present ab-initio local density FLAPW calculations on non-reactive
N-terminated [001] ordered GaN/Ag and GaN/Au interfaces and compare the results
(such as metal induced gap states and Schottky barrier heights) with those
obtained for GaN/Al, in order to understand the dependence of the relevant
electronic properties on the deposited metal. Our results show that the density
of gap states is appreciable only in the first semiconductor layer close to the
interface. The decay length of the gap states in the semiconductor side is
about 2.0 $\pm$ 0.1 \AA $\:$ and is independent of the deposited metal,
therefore being to a good extent a bulk property of GaN. Our calculated values
of the Schottky barrier heights are $\Phi_{B_p}(GaN/Ag)$ = 0.87 eV and
$\Phi_{B_p}(GaN/Au)$ = 1.08 eV; both values are smaller than the GaN/Al value
($\Phi_{B_p}(GaN/Al)$ = 1.51 eV) and this quite large spread of values excludes
the possibility of a Fermi level pinning within the GaN band gap. Because of
the low screening in GaN, the potential barrier at the junction is strongly
affected by the structural arrangement of the first metal layer at the
interface. This leads to quite large variations of the Schottky barrier height
as a function of the metal, in contrast with the behavior of GaAs/metal
interfaces.

</DOC>
<DOC>
<DOCNO> 120396 </DOCNO>
An Open Singularity-Free Cosmological Model with Inflation


  In the light of recent observations which point to an open universe
$\Omega_0<1$, we consider the singularity-free models, originally constructed
for closed universes. Our model starts from a nonsingular state called
prematter, governed by an inflationary equation of state $P=(\gamma_p-1)\rho$,
where $\gamma_p$ is a small positive parameter representing the initial vacuum
dominance of the universe. Unlike the closed models universe cannot be
initially static hence, starts with an initial ecxpansion rate represented by
the initial value of the Hubble constant H(0). Therefore, our model is a
two-parameter universe model ($\gamma_p$, H(0)). During the prematter phase,
due to the unusual characteristic of the equation of state, universe heats up
even though it expands. When the temperature in the universe reaches the Planck
temperature $T_{pl}$ which is taken as the maximum attainable physical
temperature, a first order phase transition carries the universe into the
radiation era. Then the universe starts to behave as predicted in the standard
model. The model proposed in this work predicts a value between 60 and 80
Km/sec/Mpc for the present value of the Hubble constant ($H_{0}$) and the
predicted value of $\Omega_0$ lies between 0.3 and 0.6. Comparing the
predictions of this model for the present properties of the universe with the
recent observational results, we argue that the model constructed in this paper
could be used as a realistic universe model.

</DOC>
<DOC>
<DOCNO> 122445 </DOCNO>
B1359+154: A Six Image Lens Produced by a z=1 Compact Group of Galaxies


  HST V and I-band observations show that the gravitational lens B1359+154
consists of six images of a single z_s=3.235 radio source and its star-forming
host galaxy, produced by a compact group of galaxies at z_l = 1. VLBA
observations at 1.7 GHz strongly support this conclusion, showing six compact
cores with similar low-frequency radio spectra. B1359+154 is the first example
of galaxy-scale gravitational lensing in which more than four images are
observed of the same background source. The configuration is due to the unique
lensing mass distribution: three primary lens galaxies lying on the vertices of
a triangle separated by 0.7 arcsec (4/h kpc), inside the 1.7 arcsec diameter
Einstein ring defined by the radio images. The gravitational potential has
additional extrema within this triangle, creating a pair of central images that
supplement the ``standard'' four-image geometry of the outer components. Simple
mass models consisting of three lens galaxies constrained by HST and VLBA
astrometry naturally reproduce the observed image positions but must be
finely-tuned to fit the flux densities.

</DOC>
<DOC>
<DOCNO> 122770 </DOCNO>
Sharp HI edges at high z: the gas distribution from Damped Lyman-alpha


  We derive the distribution of neutral and ionized gas in high redshift clouds
which are optically thick to hydrogen ionizing radiation, using published data
on Lyman-limit and Damped Lyman-alpha absorption systems in the redshift range
1.75 < z < 3.25. We assume that the distribution of the hydrogen total (HI+HII)
column density in the absorbers follows a power law K N_H^{-alpha}, whereas the
observed HI column density distribution deviates from a pure power law as a
result of ionization from a background radiation field. Comparison of the
models and observations give Maximum Likelihood solutions for the exponent
alpha and for X, the value of log(N_H/N_HI) when the Lyman-limit optical depth
is unity: alpha=2.7^{+1.0}_{-0.7} and X=2.75\pm0.35. X is much lower than what
would be obtained for a gaseous distribution in equilibrium under its own
gravity but the ratio of dark matter to gas density is not well constrained
being log(eta_0)=1.1\pm 0.8. An extrapolation of our derived power law
distribution towards systems of lower column density, the Lyman-alpha forest,
favours models with log(eta_0) < 1.1 and alpha=2.7-3.3. With alpha appreciably
larger than 2, Lyman-limit systems contain more gas than Damped Lyman-alpha
systems and Lyman-alpha forest clouds even more. Estimates of the cosmological
gas and dark matter density due to absorbers of different column density around
z=2.5 are also given.

</DOC>
<DOC>
<DOCNO> 8274 </DOCNO>
Long-range interaction and nonlinear localized modes in photonic crystal


  We develop the theory of nonlinear localised modes (intrinsic localised modes
or discrete breathers) in two-dimensional (2D) photonic crystal waveguides. We
consider different geometries of the waveguides created by an array of
nonlinear dielectric rods in an otherwise perfect linear 2D photonic crystal,
and demonstrate that the effective interaction in such waveguides is nonlocal,
being described by a new type of nonlinear lattice models with long-range
coupling and nonlocal nonlinearity. We reveal the existence of different types
of nonlinear guided modes which are also localised in the waveguide direction,
and describe their unique properties including bistability.

</DOC>
<DOC>
<DOCNO> 118751 </DOCNO>
A New Probe of the Molecular Gas in Galaxies: Application to M101


  Recent studies of nearby spiral galaxies suggest that photodissociation
regions (PDRs) are capable of producing much of the observed HI in galaxy
disks. In that case, measurements of the HI column density and the
far-ultraviolet (FUV) photon flux provide a new probe of the volume density of
the local underlying H_2. We develop the method and apply it to the giant Scd
spiral M101 (NGC 5457). We find that, after correction for the best-estimate
gradient of metallicity in the ISM of M101 and for the extinction of the
ultraviolet emission, molecular gas with a narrow range of density from 30-1000
cm^-3 is found near star- forming regions at all radii in the disk of M101 out
to a distance of 12' (approximately 26 kpc), close to the photometric limit of
R_25 = 13.5'.
  In this picture, the ISM is virtually all molecular in the inner parts of
M101. The strong decrease of the HI column density in the inner disk of the
galaxy at R_G < 10 kpc is a consequence of a strong increase in the dust-to-gas
ratio there, resulting in an increase of the H_2 formation rate on grains and a
corresponding disappearance of hydrogen in its atomic form.

</DOC>
<DOC>
<DOCNO> 70262 </DOCNO>
Az elektrogyenge f\'azis\'atmenet (The electroweak phase transition)


  The electroweak phase transition provides the most attractive framework to
account for the baryon asymmetry of the universe. Comparing results of
perturbative and nonperturbative studies is not straightforward, however, due
to the different coupling constant definitions. The perturbative one stems from
the $\bar{\mathrm{MS}}$ subtraction scheme, while the nonperturbative one uses
the static quark potential. The momentum-space perturbative static potential is
calculated in the SU(2)--Higgs model, and is Fourier transformed into
coordinate space. Based on the connection between the coupling constants,
two-loop perturbative and 4-dimensional lattice simulation results are
contrasted. The thermodynamical parameters of the phase transition indicate
that perturbative results are reliable only for low Higgs masses, far from the
endpoint. The value of the endpoint can be refined to $72.1\pm1.4$ GeV. The
Higgs mass range for which dimensional reduction yields reliable results is
identified. As an extension of the standard model, the MSSM is also studied.
Some useful trends are indicated by a simple one-loop perturbative approach:
baryogenesis requirements are more easily met if the stop is lighter thanthe
top; colour-breaking phase transition may be possible, etc. In order to perform
4D nonperturbative studies the supercomputer PMS was built at E\"otv\"os
University. The results and the techniques of the simulations of the bosonic
sector of the MSSM performed on PMS are presented. A phase diagram is given,
the bubble wall is studied. The cosmologically relevant part of the parameter
space is analysed. The results show that baryogenesis is possible within the
MSSM if $m_h\leq 103\pm 4$ GeV.

</DOC>
<DOC>
<DOCNO> 119793 </DOCNO>
ASCA Observation of the Crab-Like Supernova Remnant 3C58


  We present here the X-ray observation of a Crab-like supernova remnant (SNR)
3C58 with ASCA. We find that the integrated energy spectrum over the nebula is
consistent with previous results, showing a power-law spectrum with the photon
index $\gamma = 2.2-2.4$ modified by interstellar absorption of about
$(3-4)\times 10^{21}{\rm cm^{-2}}$. Inclusion of a blackbody component which is
attributable to the central compact source significantly improves the spectral
fit. Stringent upper limits for any line emitting thin hot plasma are
established. We find for the first time that the nebular spectrum is harder in
the central part of the SNR, becoming softer toward the periphery, while the
absorption column is uniform across the nebula. Correspondingly, the nebular
size decreases with increasing photon energy which is a steeper function of
radius than that of the Crab nebula. The results are compared with synchrotron
energy loss models and the nature of the putative pulsar is discussed. Timing
analysis was performed to search for pulsed X-ray emission from the central
compact source. No significant pulsations are observed, and we present the
upper limit for the pulsed fraction.

</DOC>
<DOC>
<DOCNO> 10890 </DOCNO>
Zipping and collapse of diblock copolymers


  Using exact enumeration methods and Monte Carlo simulations we study the
phase diagram relative to the conformational transitions of a two dimensional
diblock copolymer. The polymer is made of two homogeneous strands of monomers
of different species which are joined to each other at one end. We find that
depending on the values of the energy parameters in the model, there is either
a first order collapse from a swollen to a compact phase of spiral type, or a
continuous transition to an intermediate zipped phase followed by a first order
collapse at lower temperatures. Critical exponents of the zipping transition
are computed and their exact values are conjectured on the basis of a mapping
onto percolation geometry, thanks to recent results on path-crossing
probabilities.

</DOC>
<DOC>
<DOCNO> 100640 </DOCNO>
On Associative Conformal Algebras of Linear Growth


  Lie conformal algebras appear in the theory of vertex algebras. Their
relation is similar to that of Lie algebras and their universal enveloping
algebras. Associative conformal algebras play a role in conformal
representation theory. We introduce the notions of conformal identity and
unital associative conformal algebras and classify finitely generated simple
unital associative conformal algebras of linear growth. These are precisely the
complete algebras of conformal endomorphisms of finite modules.

</DOC>
<DOC>
<DOCNO> 7685 </DOCNO>
Analytical Studies of Strategies for Utilization of Cache Memory in


  We analyze quantitatively several strategies for better utilization of the
{\em cache} or the {\em {fast access}} memory in computers. We define a
performance factor $\alpha$ that denotes the fraction of the cache area
utilized when the main memory is accessed at random. We calculate $\alpha$
exactly for different competing strategies, including the hash-rehash and the
skewed-associative strategies which were earlier analyzed via simulations.

</DOC>
<DOC>
<DOCNO> 8028 </DOCNO>
High-field noise in metallic diffusive conductors


  We analyze high-field current fluctuations in degenerate conductors by
mapping the electronic Fermi-liquid correlations at equilibrium to their
semiclassical non-equilibrium form. Our resulting Boltzmann description is
applicable to diffusive mesoscopic wires. We derive a non-equilibrium
connection between thermal fluctuations of the current and resistive
dissipation. In the weak-field limit this is the canonical fluctuation-
dissipation theorem. Away from equilibrium, the connection enables explicit
calculation of the excess ``hot-electron'' contribution to the thermal
spectrum. We show that excess thermal noise is strongly inhibited by Pauli
exclusion. This behaviour is generic to the semiclassical metallic regime.

</DOC>
<DOC>
<DOCNO> 70537 </DOCNO>
Glueball Masses in Relativistic Potential Model


  The problem of glueball mass spectra using the relativistic Dirac equation is
studied. Also the Breit-Fermi approach used to obtaining hyperfine splitting in
glueballs. Our approach is based on the assumption, that the nature and the
forces between two gluons are the short-range. We were to calculate the
glueball masses with used screened potential.

</DOC>
<DOC>
<DOCNO> 121539 </DOCNO>
Star Formation and the ISM in Dwarf Galaxies


  High spatial and spectral resolution observations of the atomic interstellar
medium in nearby dwarf galaxies reveal evidence for warm and cold neutral gas,
just like the phases in our own Galaxy. The cold or quiescent phase (about 20%
of the HI in the galaxies studied, except for LGS 3) seems to be associated
with star formation activity--- it may mark the regions where the conditions
are right for star formation. These results help to explain the patterns of
star formation activity which are seen in color-magnitude data for the dwarf
irregulars.

</DOC>
<DOC>
<DOCNO> 116708 </DOCNO>
The hydration number of Na+ in liquid water


  An `ab initio' molecular dynamics simulation of a Na+ ion in aqueous solution
is presented and discussed. The calculation treats a Na+ ion and 32 water
molecules with periodic boundary conditions on a cubic volume determined by an
estimate of zero partial molar volume for this solute in water at normal
density and at a temperature of 344+/-24 K. Analysis of the last half of the 12
ps trajectory shows 4.6 water molecules occupying the inner hydration shell of
the Na+ ion on average, with 5 being the most probable occupancy. The
self-diffusion coefficient observed for the Na+ is 1.0 x 10$^{-5}$ cm$^2$/s.
The quasi-chemical theory of solutions provides the framework for two more
calculations. First a complementary calculation, based on electronic structure
results for ion-water clusters and a dielectric continuum model of outer sphere
hydration contributions, predicts an average hydration shell occupancy of 4.0.
This underestimate is attributed to the harmonic approximation for the clusters
in conjunction with the approximate dielectric continuum model treatment of
outer sphere contributions. Finally, a maximum entropy fitting of inner sphere
occupancies that leads to insensitive composite free energy approximations
suggests a value in the neighborhood of -68 kcal/mol for the hydration free
energy of Na+ (aq) under these conditions with no contribution supplied for
packing or van der Waals interactions.

</DOC>
<DOC>
<DOCNO> 68039 </DOCNO>
Effect of anomalous tbW vertex on decay-lepton distributions in e+e- ->


  We obtain analytic expressions for the energy and polar-angle double
differential distributions of a secondary lepton l+ (l-) arising from the decay
of t (tbar) in e+e- -> t tbar with an anomalous tbW decay vertex. We also
obtain analytic expressions for the various differential cross sections with
the lepton energy integrated over. In this case, we find that the angular
distributions of the secondary lepton do not depend on the anomalous coupling
in the decay, regardless of possible anomalous couplings occurring in the
production amplitude for e+e- -> t tbar. Our study includes the effect of
longitudinal e- and e+ beam polarization. We also study the lepton energy and
beam polarization dependence of certain CP-violating lepton angular asymmetries
arising from an anomalous tbW decay vertex and compare them with the
asymmetries arising due to CP violation in the production process due to the
top electric or weak dipole moment.

</DOC>
<DOC>
<DOCNO> 99437 </DOCNO>
On a Problem of Mahler Concerning the Approximation of Exponentials and


  We first propose two conjectural estimates on Diophantine approximation of
logarithms of algebraic numbers. Next we discuss the state of the art and we
give further partial results on this topic.

</DOC>
<DOC>
<DOCNO> 119556 </DOCNO>
Gamma-ray bursts from internal shocks in a relativistic wind: an


  The internal shock model for gamma-ray bursts involves shocks taking place in
a relativistic wind with a very inhomogeneous initial distribution of the
Lorentz factor. We have developed a 1D lagrangian hydrocode to follow the
evolution of such a wind and the results we have obtained are compared to those
of a simpler model presented in a recent paper (Daigne & Mochkovitch 1998)
where all pressure waves are suppressed in the wind so that shells with
different velocities only interact by direct collisions. The detailed
hydrodynamical calculation essentially confirms the conclusion of the simple
model: the main temporal and spectral properties of gamma-ray bursts can be
reproduced by internal shocks in a relativistic wind.

</DOC>
<DOC>
<DOCNO> 8966 </DOCNO>
Broad Histogram: An Overview


  The Broad Histogram is a method allowing the direct calculation of the energy
degeneracy $g(E)$. This quantity is independent of thermodynamic concepts such
as thermal equilibrium. It only depends on the distribution of allowed (micro)
states along the energy axis, but not on the energy changes between the system
and its environment. Once one has obtained $g(E)$, no further effort is needed
in order to consider different environment conditions, for instance, different
temperatures, for the same system.
        The method is based on the exact relation between $g(E)$ and the
microcanonical averages of certain macroscopic quantities $N^{\rm up}$ and
$N^{\rm dn}$. For an application to a particular problem, one needs to choose
an adequate instrument in order to determine the averages $<N^{\rm up}(E)>$ and
$<N^{\rm dn}(E)>$, as functions of energy. Replacing the usual
fixed-temperature canonical by the fixed-energy microcanonical ensemble, new
subtle concepts emerge. The temperature, for instance, is no longer an external
parameter controlled by the user, all canonical averages being functions of
this parameter. Instead, the microcanonical temperature $T_{m}(E)$ is a
function of energy defined from $g(E)$ itself, being thus an {\bf internal}
(environment independent) characteristic of the system. Accordingly, all
microcanonical averages are functions of $E$.
        The present text is an overview of the method. Some features of the
microcanonical ensemble are also discussed, as well as some clues towards the
definition of efficient Monte Carlo microcanonical sampling rules.

</DOC>
<DOC>
<DOCNO> 119286 </DOCNO>
Far infrared extragalactic background radiation: I. Source counts with


  As a part of the ISOPHOT CIRB (Cosmic Infrared Background Radiation) project
we have searched for point-like sources in eight fields mapped at two or three
wavelengths between 90 and 180um. Most sources are previously unknown and based
on the far-infrared (FIR) spectral energy distributions dust-enshrouded,
distant galaxies form a significant fraction of the sources. We present a list
of the new extragalactic FIR-sources and discuss the uncertainties of the
source detection from the ISOPHOT maps. We estimate the source number densities
at 90, 150 and 180um and at flux density levels down to 100mJy to be 10^5, 2
10^5, and 3 10^5 1/sr, respectively. Strong galaxy evolution models are in best
agreement with our results, although the number of detections exceeds most
model predictions. No-evolution models can be rejected at a high confidence
level. Comparison with COBE results indicates that at 90um the detected sources
correspond to some 20% of the extragalactic background light. At longer
wavelengths the corresponding fraction is closer to 10%.

</DOC>
<DOC>
<DOCNO> 151986 </DOCNO>
Beyond Eikonal Scattering in M(atrix)-Theory


  We study the problem of more general kinematics for the finite N
M(atrix)-Model than the simple straight line motion that has been used before.
This is supposed to be related to momentum transferring processes in the dual
super-gravity description. We find a negative result for classical,
perturbative processes and discuss briefly the possibility of instianton like
quantum mechanical tunneling processes.

</DOC>
<DOC>
<DOCNO> 118632 </DOCNO>
Supermassive Black Holes in Active Galactic Nuclei


  This article gives a brief overview of the direct and indirect evidence in
support of the standard paradigm that active galactic nuclei are powered by
supermassive black holes.

</DOC>
<DOC>
<DOCNO> 8497 </DOCNO>
Canonical solution of a system of long-range interacting rotators on a


  The canonical partition function of a system of rotators (classical X-Y
spins) on a lattice, coupled by terms decaying as the inverse of their distance
to the power alpha, is analytically computed. It is also shown how to compute a
rescaling function that allows to reduce the model, for any d-dimensional
lattice and for any alpha<d, to the mean field (alpha=0) model.

</DOC>
<DOC>
<DOCNO> 118724 </DOCNO>
Blobs in Wolf-Rayet Winds: Random Photometric and Polarimetric


  Some isolated Wolf-Rayet stars present random variability in their optical
flux and polarization. We make the assumption that such variability is caused
by the presence of regions of enhanced density, i.e. blobs, in their envelopes.
In order to find the physical characteristics of such regions we have modeled
the stellar emission using a Monte Carlo code to treat the radiative transfer
in an inhomogeneous electron scattering envelope. We are able to treat multiple
scattering in the regions of enhanced density as well as in the envelope
itself. The finite sizes of the source and structures in the wind are also
taken into account. Most of the results presented here are based on a parameter
study of models with a single blob. The effects due to multiple blobs in the
envelope are considered to a more limited extent. Our simulations indicate that
the density enhancements must have a large geometric cross section in order to
produce the observed photopolarimetric variability. The sizes must be of the
order of one stellar radius and the blobs must be located near the base of the
envelope. These sizes are the same inferred from the widths of the sub-peaks in
optical emission lines of Wolf-Rayet stars. Other early-type stars show random
polarimetric fluctuations with characteristics similar to those observed in
Wolf-Rayet stars, which may also be interpreted in terms of a clumpy wind.
Although the origin of such structures is still unclear, the same mechanism may
be working in different types of hot stars envelopes to produce such
inhomogeneities.

</DOC>
<DOC>
<DOCNO> 71929 </DOCNO>
Non Linear Breaking of the Electroweak Symmetry and Large Extra


  We consider the coupling to gravity in 4+delta dimensions of a non linear
electroweak symmetry breaking sector, with delta compactified dimensions, and
derive an effective lagrangian by integrating over the KK excitations of the
graviton and of the dilaton. The effective chiral lagrangian describes the
interactions of the electroweak gauge bosons and the goldstone bosons from the
electroweak breaking.

</DOC>
<DOC>
<DOCNO> 8319 </DOCNO>
Quantum Interleaver: Quantum Error Correction for Burst Error


  The concept of quantum interleaver and a simple method of quantum burst-error
correction is proposed. By using the quantum interleaver, any quantum
burst-errors that have occurred spread over the interleaved code word, so that
we can construct good quantum burst-error correcting codes without increasing
the redundancy of the code. We also discuss the general method of constructing
the quantum circuit for the quantum interleaver and the quantum network.

</DOC>
<DOC>
<DOCNO> 69020 </DOCNO>
Neutrino propagation in matter using the wave packet approach


  We study the oscillations and conversions of relativistic neutrinos
propagating in matter of variable density using the wave packet formalism. We
show how the oscillation and coherence lengths are modified in comparison with
the case of oscillations in vacuum. Secondly, we demonstrate how the equation
of motion for two neutrino flavors can be formally solved for almost arbitrary
density profile. We calculate finally how the use of wave packets alters the
nonadiabatic level crossing probabilities. For the most common physical
environments the corrections due to the width of the wave packet do not lead to
observable effects.

</DOC>
<DOC>
<DOCNO> 69477 </DOCNO>
O(m_d-m_u) Effects in CP-even and CP-odd K-->pi pi Decays


  Strong isospin-breaking (IB) effects in CP-even and CP-odd K-->pi pi decays
are computed to next-to-leading order (NLO) in the chiral expansion. The impact
of these corrections on the magnitude of the Delta I=1/2 Rule and on the size
of the IB correction, Omega_IB, to the gluonic penguin contribution to
epsilon'/epsilon are discussed.

</DOC>
<DOC>
<DOCNO> 9014 </DOCNO>
Enhancement of GMR due to spin-mixing in magnetic multilayers with a


  We study the Giant Magnetoresistance (GMR) ratio in magnetic multiayers with
a single superconducting contact in the presence of spin-mixing processes. It
has been recently shown that the GMR ratio of magnetic multilayers is strongly
suppressed by the presence of a superconducting contact when spin-flipping is
not allowed. In this Letter we demonstrate that the GMR ratio can be
dramatically enhanced by spin-orbit interaction and/or non-collinear magnetic
moments. The system is described using a tight-binding model with either s-p-d
or s-d atomic orbitals per site.

</DOC>
<DOC>
<DOCNO> 102457 </DOCNO>
On modular properties of odd theta-characteristics


  A general canonical curve X determines a finite set T(X) of hyperplanes,
which is in bijective correspondence with the set of odd theta-characteristics
of X. The definition of T(X) can be extended to certain singular curves, in a
way that is compatible with degenerations. If X is a Deligne-Mumford stable
curve (or a cuspidal curve), we describe the enumerative and local geometry of
T(X); this is applied to show that some singular curves are uniquely determined
by T(X). This work generalizes the preliminary steps used in AG/0008239 (with
E. Sernesi) to show that a general curve of genus 3 can be recovered from its
odd theta-characteristics.

</DOC>
<DOC>
<DOCNO> 9636 </DOCNO>
The Functional Form of Angular Forces around Transition Metal Ions in


  A method for generating angular forces around $\sigma$-bonded transition
metal ions is generalized to treat $\pi$-bonded configurations. The theoretical
approach is based on an analysis of a ligand-field Hamiltonian based on the
moments of the electron state distribution. The functional forms that are
obtained involve a modification of the usual expression of the binding energy
as a sum of ligand-ligand interactions, which however requires very little
increased in CPU time. The angular interactions have simple forms involving sin
and cos functions, whose relative weights depend on whether the ligands are
$\sigma$- or $\pi$-bonded. They describe the ligand-field stabilization energy
to an accuracy of about 10%. The resulting force field is used to model the
structure of small clusters, including fragments of the copper blue protein
structure. Large deviations from the typical square copper coordination are
found when $\pi$-bonded ligands are present.

</DOC>
<DOC>
<DOCNO> 11518 </DOCNO>
Exchange Frequencies in the 2d Wigner crystal


  Using Path Integral Monte Carlo we have calculated exchange frequencies as
electrons undergo ring exchanges in a ``clean'' 2d Wigner crystal as a function
of density. The results show agreement with WKB calculations at very low
density, but show a more rapid increase with density near melting. Remarkably,
the exchange Hamiltonian closely resembles the measured exchanges in 2d He.
Using the resulting multi-spin exchange model we find the spin Hamiltonian for
r_s \leq 175 \pm 10 is a frustrated antiferromagnetic; its likely ground state
is a spin liquid. For lower density the ground state will be ferromagnetic.

</DOC>
<DOC>
<DOCNO> 152494 </DOCNO>
Probing Naked Singularities in Non-supersymmetric String Vacua


  We present a detailed analysis of non-supersymmetric spacetime varying string
vacua which can lead to an exponential hierarchy between the electroweak and
the gravitational scales. In particular, we identify a limit in which these
vacua can be interpreted as supersymmetric vacua of F-theory. Furthermore, we
study the properties of these solutions as seen by $D7$-brane probes and
establish a non-supersymmetric analogue of the enhancon mechanism.

</DOC>
<DOC>
<DOCNO> 118762 </DOCNO>
Impulsive and Varying Injection in GRB Afterglows


  The standard model of Gamma-Ray Bursts afterglows is based on synchrotron
radiation from a blast wave produced when the relativistic ejecta encounters
the surrounding medium. We reanalyze the refreshed shock scenario, in which
slower material catches up with the decelerating ejecta and reenergizes it.
This energization can be done either continuously or in discrete episodes. We
show that such scenario has two important implications. First there is an
additional component coming from the reverse shock that goes into the
energizing ejecta. This persists for as long as the re-energization itself,
which could extend for up to days or longer. We find that during this time the
overall spectral peak is found at the characteristic frequency of the reverse
shock. Second, if the injection is continuous, the dynamics will be different
from that in constant energy evolution, and will cause a slower decline of the
observed fluxes. A simple test of the continuously refreshed scenario is that
it predicts a spectral maximum in the far IR or mm range after a few days.

</DOC>
<DOC>
<DOCNO> 118478 </DOCNO>
Accretion and Emission Processes in AGN: the UV-X Connection


  The main characteristics of the average spectrum of radio quiet AGN in the UV
and X-ray range are reviewed, and the emission mechanisms are discussed in the
framework of accretion disk models, in particular the ``irradiated cold
relativistic disk". It is shown that some problems arise in confronting the
predictions of the model to the observations. We propose an alternative model
in terms of a hot disk surrounded by a cold Compton thick medium. Finally we
mention problems with remote regions of the accretion disk.

</DOC>
<DOC>
<DOCNO> 67982 </DOCNO>
The Lifetimes of Heavy Flavour Hadrons - a Case Study in Quark-Hadron


  The status of heavy quark expansions for charm and beauty lifetime ratios is
reviewed. Taking note of the surprising semiquantitative success of this
description for charm hadrons I interprete the new data on $\tau (D_s)$ and
re-iterate the call for more precise measurements of $\tau (\Xi_c^{0,+})$ and
$\tau (\Omega_c)$. A slightly larger $B^-$ than $B_d$ lifetime is starting to
emerge as predicted; the largest lifetime difference in the beauty sector,
namely in $\tau (B_c)$ vs. $\tau (B)$ has correctly been predicted; the problem
posed by the short $\Lambda_b$ lifetime remains. The need for more accurate
data also on $\tau (B_s)$ and $\tau (\Xi_b^{-,0})$ is emphasized. I discuss
quark-hadron duality as the central theoretical issue at stake here.

</DOC>
<DOC>
<DOCNO> 152271 </DOCNO>
Anomaly-Induced Effective Action and Inflation


  In the early Universe matter can be described as a conformal invariant
ultra-relativistic perfect fluid, which does not contribute, on classical
level, to the evolution of the isotropic and homogeneous metric. If we suppose
that there is some desert in the particle spectrum just below the Planck mass,
then the effect of conformal trace anomaly is dominating at the corresponding
energies. With some additional constraints on the particle content of the
underlying gauge model (which favor extended or supersymmetric versions of the
Standard Model rather than the minimal one), one arrives at the stable
inflation. We review the model and report about the calculation of the
gravitational waves on the background of the anomaly-induced inflation. The
result for the perturbation spectrum is close to the one for the conventional
inflaton model, and is in agreement with the existing Cobe data (see also
[hep-th/0009197]).

</DOC>
<DOC>
<DOCNO> 9744 </DOCNO>
Quantum critical effects on transition temperature of magnetically


  We determine the behavior of the critical temperature of magnetically
mediated p-wave superconductivity near a ferromagnetic quantum critical point
in three dimensions, distinguishing universal and non-universal aspects of the
result. We find that the transition temperature is non-zero at the critical
point, raising the possibility of superconductivity in the ferromagnetic phase.

</DOC>
<DOC>
<DOCNO> 72064 </DOCNO>
Light-light and heavy-light mesons spectra from nonperturbative QCD


  Properties of light-light mesons are described by the effective Hamiltonian
with spinless quarks derived from QCD. The spectrum is computed by the WKB
method and shown to reproduce the celebrated linear Regge trajectories even for
the lowest levels. The correct string slope of the trajectories naturally
appears in the present approach as the string dynamics is taken into account
properly.
  Similar method is applied to heavy-light mesons and a set of corrections to
the Hamiltonian is taken into account including spin-spin and Tomas spin-orbit
interactions. The numerical results for the spectrum are compared with the
experimental data and with the results of recent lattice calculations.

</DOC>
<DOC>
<DOCNO> 10042 </DOCNO>
Electron Correlations in Narrow Energy Bands: Ground State Energy and


  The electron correlations in narrow energy bands are examined in framework of
the Hubbard model. The single-particle Green function and energy spectrum are
obtained in paramagnetic state at half-filling by means of new two-pole
approximation. In the ground state analitical expressions for the energy gap,
polar states concentration and energy of the system are found. Metal-insulator
transitions in the model at change of bandwidth or temperature are
investigated. The obtained results are used for interpretation of some
experimental data in narrow-band materials.

</DOC>
<DOC>
<DOCNO> 12052 </DOCNO>
Low temperature transport in AC-driven Quantum Dots in the Kondo regime


  We present a fully nonequilibrium calculation of the low temperature
transport properties of a quantum dot in the Kondo regime when an AC potential
is applied to the gate voltage. We solve a time dependent Anderson model with
finite on-site Coulomb interaction. The interaction self-energy is calculated
up to second order in perturbation theory in the on-site interaction, in the
context of the Keldysh non-equilibrium technique, and the effect of the AC
voltage is taken into account exactly for all ranges of AC frequencies and AC
intensities. The obtained linear conductance and time-averaged density of
states of the quantum dot evolve in a non trivial way as a function of the AC
frequency and AC intensity of the harmonic modulation.

</DOC>
<DOC>
<DOCNO> 120672 </DOCNO>
A Global Photometric Analysis of 2MASS Calibration Data


  We present results from the application of a global photometric calibration
(GPC) procedure to calibration data from the first 2 years of The Two Micron
All Sky Survey (2MASS). The GPC algorithm uses photometry of both primary
standards and moderately bright `tracer' stars in 35 2MASS calibration fields.
During the first two years of the Survey, each standard was observed on
approximately 50 nights, with about 900 individual measurements. Based on the
photometry of primary standard stars and secondary tracer stars and under the
assumption that the nightly zeropoint drift is linear, GPC ties together all
calibration fields and all survey nights simultaneously, producing a globally
optimized solution. Calibration solutions for the Northern and Southern
hemisphere observatories are found separately, and are tested for global
consistency based on common fields near the celestial equator.
  Several results from the GPC are presented, including establishing candidate
secondary standards, monitoring of near-infrared atmospheric extinction
coefficients, and verification of global validity of the standards. The
solution gives long-term averages of the atmospheric extinction coefficients,
A_J=0.096, A_H=0.026, A_{K_s}=0.066 (North) and A_J=0.092, A_H=0.031,
A_{K_s}=0.065 (South), with formal error of 0.001. The residuals show small
seasonal variations, most likely due to changing atmospheric content of water
vapor. Extension of the GPC to approximately 100 field stars in each of the 35
calibration fields yields a catalog of more than two thousand photometric
standards ranging from 10th to 14th magnitude, with photometry that is globally
consistent to $\sim 1%$.

</DOC>
<DOC>
<DOCNO> 69855 </DOCNO>
Kaon vs. Bottom: Where to look for a general MSSM?


  We analyze CP violation and Flavor Changing effects in a general Minimal
Supersymmetric extension of the Standard Model with arbitrary non-universal
soft-breaking terms. We show that, in this conditions, large FCNC effects are
naturally expected in the Kaon system, even in the absence of quark-squark
flavor misalignment. On the other hand, the B system is only sensitive to new
supersymmetric contributions if the non-universality implies, not only
different soft term for the three generations but also the presence of a
quark-squark misalignment much larger that the corresponding CKM mixing. The
only exception to this rule are processes where the chirality changing
contributions proportional to tan beta are leading (for instance b -> s gamma).

</DOC>
<DOC>
<DOCNO> 118181 </DOCNO>
Red Companions to the z=2.15 Radio Loud Quasar 1550-269


  We have conducted observations of the environment around the z=2.15 radio
loud quasar 1550-269 in search of distant galaxies associated either with it or
the z=2.09 CIV absorber along its line of sight. Such objects will be
distinguished by their red colours, R-K > 4.5. We find five such objects in a
1.5 arcmin^2 field around the quasar, with typical K' magnitudes of ~20.4 and
no detected R band emission. We also find a sixth object with K=19.6 +/- 0.3,
and undetected at R, just two arcseconds from the quasar. The nature of all
these objects is currently unclear, and will remain so until we have determined
their redshifts. We suggest that it is likely that they are associated with
either the quasar or the CIV absorber, in which case their properties might be
similar to those of the z=2.38 red Ly-alpha emitting galaxies discovered by
Francis et al. (1997). The small separation between the quasar and the
brightest of our objects suggests that it may be the galaxy responsible for the
CIV metal line absorption system. The closeness to the quasar and the red
colour might have precluded similar objects from being uncovered in previous
searches for emission from CIV and eg. damped absorbers.

</DOC>
<DOC>
<DOCNO> 102606 </DOCNO>
G-dinaturality


  An extension of the notion of dinatural transformation is introduced in order
to give a criterion for preservation of dinaturality under composition. An
example of an application is given by proving that all bicartesian closed
canonical transformations are dinatural. An alternative sequent system for
intuitionistic propositional logic is introduced as a device, and a cut
elimination procedure is established for this system.

</DOC>
<DOC>
<DOCNO> 118888 </DOCNO>
Color Gradients in Early-Type Galaxies in Clusters at the Redshift from


  Color gradients in elliptical galaxies in distant clusters ($z=0.37-0.56$)
are examined by using the archival deep imaging data of Wide Field Planetary
Camera 2 (WFPC2) on-board the Hubble Space Telescope (HST). Obtained color
gradients are compared with the two model gradients to examine the origin of
the color gradients. In one model, a color gradient is assumed to be caused by
a metallicity gradient of stellar populations, while in the other one, it is
caused by an age gradient. Both of these model color gradients reproduce the
average color gradient seen in nearby ellipticals, but predict significantly
different gradients at a redshift larger than $\sim$0.3. Comparison between the
observed gradients and the model gradients reveals that the metallicity
gradient is much more favorable as the primary origin of color gradients in
elliptical galaxies in clusters. The same conclusion has been obtained for
field ellipticals by using those at the redshift from 0.1 to 1.0 in the Hubble
Deep Field-North by Tamura et al. (2000). Thus, it is also suggested that the
primary origin of the color gradients in elliptical galaxies does not depend on
galaxy environment.

</DOC>
<DOC>
<DOCNO> 72241 </DOCNO>
Diffractive vector boson production at the Tevatron


  The diffractive production of vector bosons at the Tevatron is studied. We
take a hard pomeron flux and use the H1 parton density functions extracted from
their measurement of F_2^{D(3)}. To this we add a reggeon exchange
contribution. We find that the ratio of diffractive to non-diffractive W boson
production is in good agreement with the CDF data. We note that the poorly
understood reggeon contribution might be as large as the pomeron contribution
in the kinematic range of the data. We also note that our pomeron exchange
contribution is much smaller than earlier predictions due to our use of a hard
pomeron flux. All our results have been obtained using the lowest order matrix
elements and we have compared to the results obtained using a modified version
of Herwig which is capable of generating a wide variety of diffractive
scattering processes. Gap survival is estimated using Pythia and is found to be
around 60%. We make predictions which could be compared to future measurements
of diffractive Drell-Yan production.

</DOC>
<DOC>
<DOCNO> 120727 </DOCNO>
Cygnus X-1 from RXTE: Monitoring the short term variability


  We present temporal and spectral results from monitoring Cygnus X-1 with the
Rossi X-ray Timing Explorer (RXTE) in 1998 and 1999. We concentrate on the long
term evolution of the hard state timing properties, comparing it to the 1996
soft state evolution. This leads to the following results: 1. the hard and soft
state time lag spectra are very similar, 2. during state transitions, the lags
in the 1-10 Hz range increase by more than an order of magnitude, 3. in the
hard state itself, flaring events can be seen --- the temporal and spectral
evolution during the flare of 1998 July identifies it as a ``failed state
transition''. During (failed) state transitions, the time lag spectra and the
power spectra change predominantly in the 1-10 Hz range. We suggest that this
additional variability is produced in ejected coronal material disrupting the
synchrotron radiation emitting outflows present in the hard state.

</DOC>
<DOC>
<DOCNO> 100381 </DOCNO>
Disjointly strictly singular inclusions of symmetric spaces


  A condition for the presence of a "gap" between symmetric spaces sufficient
for the inclusion of one of these spaces into the other to be disjointly
strictly singular is found. This condition is stated in terms of fundamental
functions of spaces and is exact in a certain sense. In parallel, necessary and
sufficient conditions for an inclusion of Lorentz spaces to be disjointly
strictly singular are obtained.

</DOC>
<DOC>
<DOCNO> 117778 </DOCNO>
Radio-optical identification of very-steep spectrum radio sources from


  We used radio source catalogues accessible from the CATS database
(http://cats.sao.ru) to establish radio continuum spectra for decametric radio
sources in the UTR-2 catalogue (Braude et al., 1978--1994). From these, we
select a sample of 23 sources with ultra steep radio spectra (\alpha<=-1.2, S ~
\nu^{\alpha}) and present accurate positions and sizes from FIRST and NVSS. The
search for optical counterparts from the APM (object) and DSS (image)
databases, as well as infrared and X-ray identifications of these UTR sources
are in progress.

</DOC>
<DOC>
<DOCNO> 7897 </DOCNO>
Chaotic Symmetry Breaking and Dissipative Two-Field Dynamics


  The dynamical symmetry breaking in a two-field model is studied by
numerically solving the coupled effective field equations. These are
dissipative equations of motion that can exhibit strong chaotic dynamics. By
choosing very general model parameters leading to symmetry breaking along one
of the field directions, the symmetry broken vacua make the role of transitory
strange attractors and the field trajectories in phase space are strongly
chaotic. Chaos is quantified by means of the determination of the fractal
dimension, which gives an invariant measure for chaotic behavior. Discussions
concerning chaos and dissipation in the model and possible applications to
related problems are given.

</DOC>
<DOC>
<DOCNO> 121907 </DOCNO>
Hydrodynamic Effects on the QPO Frequencies of Accreting Compact Objects


  The variability properties of accreting compact objects predicted by
dynamical models are characterized by a number of distinct frequencies that are
specific to each model. Because the accretion disks around neutron stars and
black holes are hydrodynamic flows, these modulation frequencies cannot be
strictly equal to test particle frequencies. I discuss several implications of
hydrodynamic corrections to the modulation frequencies predicted by dynamical
models. Finally, I show that the recent detection of yet a third kHz QPO in
three neutron-star systems favors a previously developed model that attributes
the various QPO frequencies to fundamental general relativistic frequencies in
the accretion flow.

</DOC>
<DOC>
<DOCNO> 80803 </DOCNO>
Numerical Study of Gluon Propagator and Confinement Scenario in Minimal


  We present numerical results in SU(2) lattice gauge theory for the
space-space and time-time components of the gluon propagator at equal time in
the minimal Coulomb gauge. It is found that the equal-time would-be physical
3-dimensionally transverse gluon propagator $D^{tr}(\vec{k})$ vanishes at
$\vec{k} = 0$ when extrapolated to infinite lattice volume, whereas the
instantaneous color-Coulomb potential $D_{44}(\vec{k})$ is strongly enhanced at
$\vec{k} = 0$. This has a natural interpretation in a confinement scenario in
which the would-be physical gluons leave the physical spectrum while the
long-range Coulomb force confines color. Gribov's formula $D^{tr}(\vec{k}) =
(|\vec{k}|/2)[(\vec{k}^2)^2 + M^4]^{1/2}$ provides an excellent fit to our data
for the 3-dimensionally transverse equal-time gluon propagator
$D^{tr}(\vec{k})$ for relevant values of $\vec{k}$.

</DOC>
<DOC>
<DOCNO> 170606 </DOCNO>
Multiparticle entanglement and its experimental detection


  We discuss several aspects of multiparticle mixed state entanglement and its
experimental detection. First we consider entanglement between two particles
which is robust against disposals of other particles. To completely detect
these kinds of entanglement, full knowledge of the multiparticle density matrix
(or of all reduced density matrixes) is required. Then we review the relation
of the separability properties of l-partite splittings of a state $\rho$ to its
multipartite entanglement properties. We show that it suffices to determine the
diagonal matrix elements of $\rho$ in a certain basis in order to detect
multiparticle entanglement properties of $\rho$. We apply these observations to
analyze two recent experiments, where multiparticle entangled states of 3 (4)
particles were produced. Finally, we focus on bound entangled states
(non-separable, non-distillable states) and show that they can be activated by
joint actions of the parties. We also provide several examples which show the
activation of bound entanglement with bound entanglement.

</DOC>
<DOC>
<DOCNO> 99583 </DOCNO>
L^2 Cohomology on coverings of a compact K\"ahler manifold


  Andreotti-Vesentini, Ohsawa, Gromov, Koll\'ar, among others, have observed
that Hodge theory could be extended to (non compact) K\"ahler complete
manifolds, within the L^2 framework. Also, many vanishing theorems on
projective or K\"ahler manifolds rely on the Kodaira-Bochner-Nakano identity,
and thus possess natural L^2 versions. Our goal is to define canonical L^2
cohomology groups on any unramified covering of an analytic variety X, with
values in a coherent analytic sheaf on X. This cohomology shares all usual
properties of standard coherent sheaf cohomology (especially, exact sequences,
spectral sequences, vanishing theorems,...). These properties are obtained by
incorporating the information provided by L^2 estimates in the standard proofs,
with suitable adaptations. L^2 cohomology should provide a comfortable and
efficient framework for the study the geometry of coverings, by providing a
relevant fonctorial formalism. When the base variety is compact and the
covering is a Galois covering of group $\Gamma$, there is a $\Gamma$ action on
cohomology groups and a related concept of $\Gamma$-dimension. In that case, we
prove that the $\Gamma$-dimension of cohomology groups is finite, and we extend
Atiyah's L^2 index theorem to the case of arbitrary coherent sheaves. Finally,
if the base manifold is projective, L^2 analogues of the usual vanishing
theorems (Kodaira-Serre, Kawamata-Viehweg,...) are valid. Similar constructions
and results have also been studied by P. Eyssidieux.

</DOC>
<DOC>
<DOCNO> 178736 </DOCNO>
The role of $\sigma$-meson in $\omega\to \pi\pi\gamma$ decays and the


  We study the $\omega\to\pi\pi\gamma$ decays by adding to the amplitude
calculated within the framework of chiral perturbation theory and vector meson
dominance the amplitude of $\sigma$-meson intermediate state. We estimate the
coupling constant $g_{\omega\sigma\gamma}$ utilizing the experimental value of
the $\omega\to\pi^{0}\pi^{0}\gamma$ decay rate.

</DOC>
<DOC>
<DOCNO> 117148 </DOCNO>
Wannier-Stark states of a quantum particle in 2D lattices


  A simple method of calculating the Wannier-Stark resonances in 2D lattices is
suggested. Using this method we calculate the complex Wannier-Stark spectrum
for a non-separable 2D potential realized in optical lattices and analyze its
general structure. The dependence of the lifetime of Wannier-Stark states on
the direction of the static field (relative to the crystallographic axis of the
lattice) is briefly discussed.

</DOC>
<DOC>
<DOCNO> 70994 </DOCNO>
Matter Enhancement of T Violation in Neutrino Oscillation


  We study the matter enhancement of T violation in neutrino oscillation with
three generations. The magnitude of T violation is proportional to Jarlskog
factor J. Recently, the elegant relation,
(\Delta_m)_{12}(\Delta_m)_{23}(\Delta_m)_{31}J_{m} =
\Delta_{12}\Delta_{23}\Delta_{31}J, was derived, where \Delta_{ij}=\Delta
m^2_{ij}/(2E) and subscript m implies the quantities in matter. Using this
relation, we reconsider how J_m changes as a function of the matter potential a
under the approximation |\Delta m^2_{12}| \ll |\Delta m^2_{13}|. We show that
the number of maxima for J_{m} depends on the magnitude of \sin^2 2 \theta_{13}
and there are two maxima considering the constraint on \sin^2 2\theta_{13} from
the CHOOZ experiment. One maximum of $J_{m} at a = O(\Delta_{12}) is given by
J/\sin2\theta_{12}, which leads to the large enhancement of J_m in the case of
the SMA MSW solution. The other maximum at a = O(\Delta_{13}) is
|\Delta_{12}/\Delta_{13}|J/\sin2\theta_{13}, and the enhancement is possible,
if \sin 2 \theta_{13} is small enough. These maximal values are consistent with
the results obtained by other methods.

</DOC>
<DOC>
<DOCNO> 40077 </DOCNO>
TESLA*HERA Based gamma-p and gamma-A Colliders


  Main parameters and physics search potential of gamma-p and gamma-A
colliders, which will be available due to constructing the TESLA linear
electron-positron collider tangentially to the HERA proton ring, are discussed.

</DOC>
<DOC>
<DOCNO> 40374 </DOCNO>
The Experiment Road to the Heavier Quarks and Other Heavy Objects


  After a brief history of heavy quarks, I will discuss charm, bottom, and top
quarks in turn. For each one, I discuss its first observation, and then what we
have learned about production, hadronization, and decays - and what these have
taught us about the underlying physics. I will also point out remaining open
issues. For this series of lectures, the charm quark will be emphasized. It is
the first of the heavy quarks, and its study is where many of the techniques
and issues first appeared. Only very brief mention is made of CP violation in
the bottom-quark system since that topic is the subject of a separate series of
lectures by Gabriel Lopez. As the three quarks are reviewed, a pattern of
techniques and lessons emerges. These are identified, and then briefly
considered in the context of anticipated physics signals of the future; e.g.,
for Higgs and SUSY particles.

</DOC>
<DOC>
<DOCNO> 71534 </DOCNO>
Solutions to the cosmological constant problems


  We critically review several recent approaches to solving the two
cosmological constant problems. The "old" problem is the discrepancy between
the observed value of $\Lambda$ and the large values suggested by particle
physics models. The second problem is the "time coincidence" between the epoch
of galaxy formation $t_G$ and the epoch of $\Lambda$-domination $t_\L$. It is
conceivable that the "old" problem can be resolved by fundamental physics
alone, but we argue that in order to explain the "time coincidence" we must
account for anthropic selection effects. Our main focus here is on the
discrete-$\Lambda$ models in which $\Lambda$ can change through nucleation of
branes. We consider the cosmology of this type of models in the context of
inflation and discuss the observational constraints on the model parameters.
The issue of multiple brane nucleation raised by Feng {\it et. al.} is
discussed in some detail. We also review continuous-$\L$ models in which the
role of the cosmological constant is played by a slowly varying potential of a
scalar field. We find that both continuous and discrete models can in principle
solve both cosmological constant problems, although the required values of the
parameters do not appear very natural. M-theory-motivated brane models, in
which the brane tension is determined by the brane coupling to the four-form
field, do not seem to be viable, except perhaps in a very tight corner of the
parameter space. Finally, we point out that the time coincidence can also be
explained in models where $\Lambda$ is fixed, but the primordial density
contrast $Q=\delta\rho/\rho$ is treated as a random variable.

</DOC>
<DOC>
<DOCNO> 12837 </DOCNO>
Tracer dispersion in two-dimensional rough fractures


  Tracer diffusion and hydrodynamic dispersion in two-dimensional fractures
with self-affine roughness is studied by analytic and numerical methods.
Numerical simulations were performed via the lattice-Boltzmann approach, using
a new boundary condition for tracer particles that improves the accuracy of the
method. The reduction in the diffusive transport, due to the fractal geometry
of the fracture surfaces, is analyzed for different fracture apertures. In the
limit of small aperture fluctuations we derive the correction to the diffusive
coefficient in terms of the tortuosity, which accounts for the irregular
geometry of the fractures. Dispersion is studied when the two fracture surfaces
are simple displaced normally to the mean fracture plane, and when there is a
lateral shift as well. Numerical results are analyzed using the
$\Lambda$-parameter, related to convective transport within the fracture, and
simple arguments based on lubrication approximation. At very low P\'eclet
number, in the case where fracture surfaces are laterally shifted, we show
using several different methods that convective transport reduces dispersion.

</DOC>
<DOC>
<DOCNO> 101072 </DOCNO>
Atoms with bosonic "electrons" in strong magnetic fields


  We study the ground state properties of an atom with nuclear charge $Z$ and
$N$ bosonic ``electrons'' in the presence of a homogeneous magnetic field $B$.
We investigate the mean field limit $N\to\infty$ with $N/Z$ fixed, and identify
three different asymptotic regions, according to $B\ll Z^2$, $B\sim Z^2$, and
$B\gg Z^2$. In Region 1 standard Hartree theory is applicable. Region 3 is
described by a one-dimensional functional, which is identical to the so-called
Hyper-Strong functional introduced by Lieb, Solovej and Yngvason for atoms with
fermionic electrons in the region $B\gg Z^3$; i.e., for very strong magnetic
fields the ground state properties of atoms are independent of statistics. For
Region 2 we introduce a general {\it magnetic Hartree functional}, which is
studied in detail. It is shown that in the special case of an atom it can be
restricted to the subspace of zero angular momentum parallel to the magnetic
field, which simplifies the theory considerably. The functional reproduces the
energy and the one-particle reduced density matrix for the full $N$-particle
ground state to leading order in $N$, and it implies the description of the
other regions as limiting cases.

</DOC>
<DOC>
<DOCNO> 120795 </DOCNO>
High resolution images at 11 and 20 microns of the Active Galactic


  We present diffraction-limited IR images at 11.2 and 20.5 microns of the
central 6''x6'' region in NGC 1068, collected with the CAMIRAS instrument
mounted at the f/36 IR focus of the CFHT/Hawaii 3.6m telescope and at the f/35
IR focus of the ESO/La Silla 3.6m telescope, respectively. After deconvolution,
the achieved resolution (0.6'') reveals a prominent central core emitting about
95 % of the total flux at these wavelengths, as well as extended emission, to
the South-West and to the North-East, broken into patchy components which are
particularly conspicuous at 20.5 microns and can be isolated as individual
clouds. The central core shows an East-West FWHM of 0.6'' (hence unresolved)
and a North-South FWHM of 0.9'' corresponding to a resolved full size extension
of abound 100 pc. Such an elongated shape is in agreement with model
predictions of a dusty/molecular torus surrounding the central engine in NGC
1068, observed under an inclination angle around 65 degrees.

</DOC>
<DOC>
<DOCNO> 72309 </DOCNO>
Factorial correlators: angular scaling within QCD jets


  Factorial correlators measure the amount of dynamical correlation in
multiplicity between two separated phase-space windows. We present the
analytical derivation of factorial correlators for a QCD jet described at the
double logarithmic (DL) accuracy. We obtain a new angular scaling property for
properly normalized correlators between two solid-angle cells or two rings
around the jet axis. Normalized QCD factorial correlators scale with the
angular distance and are independent of the window size. Scaling violations are
expected beyond DL approximation, in particular from the subjet structure.
Experimental tests are feasible, and thus welcome.

</DOC>
<DOC>
<DOCNO> 71080 </DOCNO>
Recoil and Threshold Corrections in Short-distance Cross Sections


  We identify and resum corrections associated with the kinematic recoil of the
hard scattering against soft-gluon emission in single-particle inclusive cross
sections. The method avoids double counting and conserves the flow of partonic
energy. It reproduces threshold resummation for high-p_T single-particle cross
sections, when recoil is neglected, and Q_T-resummation at low Q_T, when
higher-order threshold logarithms are suppressed. We exhibit explicit resummed
cross sections, accurate to next-to-leading logarithm, for electroweak
annihilation and prompt photon inclusive cross sections.

</DOC>
<DOC>
<DOCNO> 116472 </DOCNO>
Lorentz-Covariant Hamiltonian Formalism


  The dynamic of a classical system can be expressed by means of Poisson
brackets. In this paper we generalize the relation between the usual non
covariant Hamiltonian and the Poisson brackets to a covariant Hamiltonian and
new brackets in the frame of the Minkowski space. These brackets can be related
to those used by Feynman in his derivation of Maxwell's equations. The case of
curved space is also considered with the introduction of Christoffel symbols,
covariant derivatives, and curvature tensors.

</DOC>
<DOC>
<DOCNO> 99489 </DOCNO>
Frobenius_infinity invariants of homotopy Gerstenhaber algebras I


  We construct a functor from the derived category of homotopy Gerstenhaber
algebras with finite-dimensional cohomology to the purely geometric category of
so-called $F_{\infty}$-manifolds. The latter contains Frobenius manifolds as a
subcategory (so that a pointed Frobenius manifold is itself a homotopy
Gerstenhaber algebra). If a homotopy Gerstenhaber algebra happens to be formal
as a $L_{\infty}$-algebra, then its $F_{\infty}$-manifold comes equipped with
the Gauss-Manin connection. Mirror Symmetry implications are discussed.

</DOC>
<DOC>
<DOCNO> 11124 </DOCNO>
Low-Lying Excitations from the Yrast Line of Weakly Interacting Trapped


  Through an extensive numerical study, we find that the low-lying,
quasi-degenerate eigenenergies of weakly-interacting trapped N bosons with
total angular momentum L are given in case of small L/N and sufficiently small
L by E = L hbar omega + g[N(N-L/2-1)+1.59 n(n-1)/2], where omega is the
frequency of the trapping potential and g is the strength of the repulsive
contact interaction; the last term arises from the pairwise repulsive
interaction among n octupole excitations and describes the lowest-lying
excitation spectra from the Yrast line. In this case, the quadrupole modes do
not interact with themselves and, together with the octupole modes, exhaust the
low-lying spectra which are separated from others by N-linear energy gaps.

</DOC>
<DOC>
<DOCNO> 85242 </DOCNO>
On the motion of rotating bodies in field gravity theory and general


  On the basis of Lagrangian formalism of relativistic field theory
post-Newtonian equations of motion for a rotating body are derived in the frame
of Feynman's quantum field gravity theory (FGT) and compared with corresponding
geodesic equations in general relativity (GR). It is shown that in FGT the
trajectory of a rotating test body does not depend on a choice of a coordinate
system. The equation of translational motion of a gyroscope is applied to
description of laboratory experiments with free falling rotating bodies and
rotating bodies on a balance scale. Post-Newtonian relativistic effect of
periodical modulation of the orbital motion of a rotating body is discussed for
the case of planets of the solar system and for binary pulsars PSR B1913+16 and
PSR B1259-63. In the case of binary pulsars with known spin orientations this
effect gives a possibility to measure radiuses of neutron stars.

</DOC>
<DOC>
<DOCNO> 12917 </DOCNO>
Frequency-dependent shot noise in long disordered SNS contacts


  The shot noise in long diffusive SNS contacts is calculated using the
semiclassical approach. At low frequencies and for purely elastic scattering,
the voltage dependence of the noise is of the form S_I = (4\Delta + 2eV)/3R.
The electron-electron scattering suppresses the noise at small voltages
resulting in vanishing noise yet infinite dS_I/dV at V = 0. The distribution
function of electrons consists of a series of steps, and the frequency
dependence of noise exhibits peculiarities at \omega = neV, \omega = neV -
2\Delta, and \omega = 2\Delta - neV for integer n.

</DOC>
<DOC>
<DOCNO> 80681 </DOCNO>
Renormalization of the \Delta B=2 four-quark operators in lattice NRQCD


  We calculate perturbative renormalization constants for the \Delta B=2
four-quark operators in lattice NRQCD.
  Continuum operators \bar{b}\gamma_{\mu}(1-\gamma_5)q~
  \bar{b}\gamma_{\mu}(1-\gamma_5)q and
\bar{b}(1-\gamma_5)q~\bar{b}(1-\gamma_5)q, which are necessary in evaluating
the mass and width differences in $B^0_{d(s)}-\bar{B}^0_{d(s)}$ systems, are
matched at one-loop with corresponding lattice operators constructed from the
NRQCD heavy quarks and the ${\cal O}(a)$-improved light quarks. Using these
perturbative coefficients, we also reanalyse our previous simulation results
for the matrix elements of the above operators. Our new results are free from
the systematic error of ${\cal O}(\alpha_s/(aM_b))$ in contrast to the previous
ones with matching coefficients evaluated in the static limit.

</DOC>
<DOC>
<DOCNO> 118988 </DOCNO>
Vacuum Energy: Cosmological Constant or Quintessence?


  For a flat universe presently dominated by smooth energy, either cosmological
constant (LCDM) or quintessence (QCDM), we calculate the asymptotic collapsed
mass fraction as function of the present ratio of smooth energy to matter
energy $\mathcal R_0$. Identifying the normalized collapsed fraction as a
conditional probability for habitable galaxies, we observe that the observed
present ratio $\mathcal R_0 \sim 2$ is likely in LCDM, but more likely in QCDM.
Inverse application of Bayes' Theorem makes the Anthropic Principle a
predictive scientific principle: the data implies that the prior probability
for $\mathcal R_0$ must be essentially flat over the anthropically allowed
range. Interpreting this prior as a distribution over {\em theories} lets us
predict that any future theory of initial conditions must be indifferent to
$\mathcal R_0$. This application of the Anthropic Principle does not demand the
existence of other universes.

</DOC>
<DOC>
<DOCNO> 117610 </DOCNO>
Are HVCs Produced in Galactic Fountains?


  Three-dimensional simulations of the disk-halo interaction show the formation
of a thick HI and HII gas disk with different scale heights. The thick HI disk
prevents the disk gas from expanding freely upwards, unless some highly
energetic event such as chimneys occurs, whereas the thick HII disk acts as a
disk-halo interaction region from where the hot ionized gas flows freely into
the halo.
  The upflowing gas reaches the maximum height at $z\sim 9.3\pm 1$ kpc becoming
thermally unstable due to radiative losses, and condenses into HI clouds.
Because the major fraction of the gas is gravitationally bound to the Galaxy,
the cold gas returns to the disk. The descending clouds will have at some
height high velocities. In a period of 200 Myr of fountain evolution, some 10
percent of the total number of clouds are HVCs.

</DOC>
<DOC>
<DOCNO> 101058 </DOCNO>
Orbifolds and Finite Group Representations


  We present our recent understanding on resolutions of Gorenstein orbifolds,
which involves the finite group representation theory. We shall only concern
the quotient singularities of hypersurface type. The group $A_r(n)$ of the
A-type hypersurface quotient singularity of dimension $n$ is introduced. For
$n=4$, the structure of Hilbert scheme of group orbits and crepant resolutions
of $A_r(4)$-singularity is explained, and the flop procedure of 4-folds is
explicitly constructed through the process.

</DOC>
<DOC>
<DOCNO> 13856 </DOCNO>
Intermediate liquid-solid regime near the quantum melting of a two


  For intermediate values of the Coulomb energy to Fermi energy ratio $r_s$,
the ground state of a few spinless fermions confined on a two dimensional torus
is the quantum superposition of a floppy Wigner molecule with delocalized
vacancies and of a Fermi liquid of intersticial particles. This raises the
question of the existence of an unnoticed liquid-solid phase between the Fermi
liquid and the Wigner crystal for fermionic systems in two dimensions.

</DOC>
<DOC>
<DOCNO> 101043 </DOCNO>
The Space of Kaehler metrics


  Donaldson conjectured \cite{Dona96} that the space of K\"ahler metrics is
geodesic convex by smooth geodesic and that it is a metric space. Following
Donaldson's program, we verify the second part of Donaldson's conjecture
completely and verify his first part partially. We also prove that the constant
scalar curvature metric is unique in {\bf each} K\"{a}hler class if the first
Chern class is either strictly negative or 0. Furthermore, if $C_1 \leq 0,$ the
constant scalar curvature metric realizes the global minimum of Mabuchi energy
functional; thus it provides a new obstruction for the existence of constant
curvature metric: if the infimum of Mabuchi energy (taken over all metrics in a
fixed K\"{a}hler class) isn't bounded from below, then there doesn't exist a
constant curvature metric. This extends the work of Mabuchi and
Bando\cite{Bando87}: they showed that Mabuchi energy bounded from below is a
necessary condition for the existence of K\"{a}hler-Einstein metrics in the
first Chern class.

</DOC>
<DOC>
<DOCNO> 119652 </DOCNO>
Embedded, Self-Gravitating Equilibria in Sheetlike and Filamentary


  Numerical solutions of the isothermal Lane-Emden equation are presented,
corresponding to self-gravitating gaseous cores embedded within a finite
density envelope of overall cylindrical symmetry. These structures may be
members of a fragmentation hierarchy proceeding from sheets, to filaments, to
elongated, prolate clumps. The embedded solutions are the first of their kind,
and as such represent a significant improvement upon the isolated cloud
paradigm used almost exclusively by previous authors. The properties of the
equilibria are in reasonable agreement with observations of dense molecular
cores in star-forming clouds, despite the fact that there is only one free
parameter in the models. We show that this parameter may be identified with the
critical wavelength for instability in the parent filament. The implications of
further fragmentation and the possible influence of magnetic fields are briefly
discussed.

</DOC>
<DOC>
<DOCNO> 71378 </DOCNO>
Numerical simulations of electroweak baryogenesis at preheating


  It has recently been suggested that the baryon washout problem of standard
electroweak baryogenesis could be avoided if inflation ends at a low enough
energy density and a parametric resonance transfers its energy repidly into the
standard model fields. We present preliminary results of numerical simulations
in a SU(2)xU(1) gauge-Higgs model in which this process was studied.

</DOC>
<DOC>
<DOCNO> 8813 </DOCNO>
Hydrodynamic approach to TDDFT; response properties of metal clusters


  Performing electronic structure calculations for large systems, such as
nanoparticles or metal clusters, via orbital based Hartree-Fock or Kohn-Sham
theories is computationaly demanding. To study such systems, therefore, we have
taken recourse to the hydrodynaic approach to time-dependent density functonal
theory. In this paper we develop variation-perturbation method within this
theory in terms of the particle and the current densities of a system. We then
apply this to study the linear and nnlinear resonse properties of alkali metal
clusters within spherical jellium backgrond model.

</DOC>
<DOC>
<DOCNO> 69028 </DOCNO>
Extremely High Energy and Violation of Lorentz Invariance


  Extremely high-energy(EHE) cosmic rays might provide a chance to check a
violation of the Lorentz symmetry of spacetime. Some theoretical consideration
is described about why the Lorentz symmetry might break-down in EHE phenomena
in this universe. Some models which introduce the violation of the Lorentz
symmetry will be discussed.

</DOC>
<DOC>
<DOCNO> 85633 </DOCNO>
Hamiltonian Approach To 2+1 Dimensional Gravity


  It is shown that the reduced particle dynamics of 2+1 dimensional gravity in
the maximally slicing gauge is of hamiltonian nature. We give the exact
diffeomorphism which transforms the expression of the spinning cone geometry in
the Deser, Jackiw, 't Hooft gauge to the maximally slicing gauge. It is
explicitly shown that the boundary term in the action, written in hamiltonian
form gives the Hamiltonian for the reduced particle dynamics. The quantum
mechanical translation of the two particle Hamiltonian is given and the Green
function computed.

</DOC>
<DOC>
<DOCNO> 123053 </DOCNO>
On the Origin of Subdwarf B Stars and Related Metal-Rich Binaries


  Mounting evidence from subdwarf B (sdB) stars in the galactic field and their
recently discovered counterparts in old open clusters indicates that at least
two thirds of local disk sdB stars are binaries. Our recent radial velocity
survey showed that sdB binaries naturally divide into two groups with
contrasting spectroscopic and kinematic properties. Those with detectable
spectral lines from a cooler companion invariably have periods longer than a
year, while very short period sdB's have essentially invisible companions. We
derive typical orbital separations for the components of the composite spectrum
sdB's from their velocities. The current systems must have been produced by
Roche lobe overflow/mass transfer from low mass, metal-rich giants near the
first red giant branch tip, without undergoing common envelope envolution. The
same process should also occur at slightly lower red giant luminosities,
producing a wide binary with a helium white dwarf instead of an sdB star. Most
short period sdB's probably result from a common envelope following Roche lobe
overflow of the initial secondary onto the white dwarf. Rare post-common
envelope sdB + main sequence (MS) binaries also exist, but available data
suggest that most such systems involving lower MS companions end up merging.
The small and nearly identical masses of the two known MS survivors in short
period sdB binaries imply that both components must have lost a large fraction
of their initial mass in the common envelope process.

</DOC>
<DOC>
<DOCNO> 12835 </DOCNO>
Overview: Energy Absorption by Driven Mesoscopic Systems


  There are three regimes in the theory of energy absorption: The adiabatic
regime, the linear-response (Kubo) regime, and the non-perturbative regime. The
mesoscopic Drude formula for electrical conductance, and the wall formula for
friction, can be regarded as special cases of the general formulation of the
dissipation problem. The overview is based on a research report for 1998-2000.

</DOC>
<DOC>
<DOCNO> 119134 </DOCNO>
Unbiased reconstruction of the mass function using microlensing survey


  The large number of microlensing events discovered towards the Galactic Bulge
bears the promise to reconstruct the stellar mass function. The more
interesting issue concerning the mass function is certainly to probe its low
mass end. However due to the source confusion, even if the distribution and the
kinematics of the lenses are known, the estimation of the mass function is
extremely biased at low masses. The blending due to the source confusion biases
the duration of the event, which in turn dramatically biases the estimation of
the mass of the lens. To overcome this problem we propose to use differential
photometry of the microlensing events obtained using the image subtraction
method. Differential photometry is free of any bias due to blending, however
the drawback of differential photometry is that the baseline flux is unknown.
In this paper we will show that even without knowing the baseline flux, purely
differential photometry allow to estimate the mass function without any biases.
The basis of the method is that taking the scalar product of the microlensing
light curves with a given function and taking its sum over all the microlensing
events is equivalent to project the mass function on another function. This
method demonstrates that there is a direct correspondancy between the space of
the observations and the space of the mass function. Concerning the function to
use in order to project the observations, we show that the principal components
of the light curves are an optimal set. To illustrate the method we simulate
sets consistent with the microlensing experiments. By using 1000 of these
simulations, we show that for instance the exponent of the mass function can be
reconstructed without any biases.

</DOC>
<DOC>
<DOCNO> 116804 </DOCNO>
Rectangular Waveguide HOM Couplers for a TESLA Superstructure


  Some modifications of a Rectangular Waveguide HOM couplers for TESLA
superstructure have been investigated. These RWG HOM couplers are to be
installed between the cavities of the superstructure and also at the both ends
of it. We investigated a RWG HOM coupler attached to the beam pipe through the
slots orientated along beam pipe axis (longitudinal slots), perpendicular to it
(azimutal slots) and at some angle to this axis. For dipole modes of both
polarizations damping two RWG in every design were used. This paper presents
the results obtained for scaled-up setup at 3 GHz at room temperature. The
advantages of HOM coupler with longitudinal slots for damping dipole modes and
compact HOM coupler with slots at some angle to the axis are shown. Arrangement
of HOM coupler in cryostat and heating due to HOM and FM losses are presented.
Calculations and design of the feeding RWG coupler for superstructure are also
presented.

</DOC>
<DOC>
<DOCNO> 14167 </DOCNO>
Theory of Multi-gap Superfluidity Based on Fermi-liquid Approach


  Superfluid-to-superfluid phase transitions in a Fermi-liquid leading to the
emergence of two-gap superfluid states have been studied.
  There are considered the systems of fermions of one and two (nuclear matter)
sorts. The self-consistent equations describing new two-gap superfluid states
have been obtained. These equations differ essentially from the equations of
the BCS theory. The solutions of the self-consistent equations corresponding to
one-gap and two-gap superfluid states have been found.

</DOC>
<DOC>
<DOCNO> 169645 </DOCNO>
A four-party unlockable bound-entangled state


  I present a four-party unlockable bound-entangled state, that is, a
four-party quantum state which cannot be written in a separable form and from
which no pure entanglement can be distilled by local quantum operations and
classical communication among the parties, and yet when any two of the parties
come together in the same laboratory they can perform a measurement which
enables the other two parties to create a pure maximally entangled state
between them without coming together. This unlocking ability can be viewed in
two ways, as either a determination of which Bell state is shared in the
mixture, or as a kind of quantum teleportation with cancellation of Pauli
operators.

</DOC>
<DOC>
<DOCNO> 120005 </DOCNO>
Probing the Atmospheres of Planets Orbiting Microlensed Stars via


  We present a new method to identify and probe planetary companions of stars
in the Galactic Bulge and Magellanic Clouds using gravitational microlensing.
While spectroscopic studies of these planets is well beyond current
observational techniques, monitoring polarization fluctuations during high
magnification events induced by binary microlensing events will probe the
composition of the planetary atmospheres, an observation which otherwise is
currently unattainable even for nearby planetary systems.

</DOC>
<DOC>
<DOCNO> 13102 </DOCNO>
A growth model in a random environment


  We consider a model of interface growth in two dimensions, given by a height
function on the sites of the one--dimensional integer lattice. According to the
discrete time update rule, the height above the site $x$ increases to the
height above $x-1$, if the latter height is larger; otherwise the height above
$x$ increases by 1 with probability $p_x$. We assume that $p_x$ are chosen
independently at random with a common distribution $F$, and that the initial
state is such that the origin is far above the other sites. We explicitly
identify the asymptotic shape and prove that, in the pure regime, the
fluctuations about that shape, normalized by the square root of time, are
asymptotically normal. This contrasts with the quenched version: conditioned on
the environment, and normalized by the cube root of time, the fluctuations
almost surely approach a distribution known from random matrix theory.

</DOC>
<DOC>
<DOCNO> 8413 </DOCNO>
Striped quantum Hall phases


  Recent experiments seem to confirm predictions that interactions lead to
charge density wave ground states in higher Landau levels. These new
``correlated'' ground states of the quantum Hall system manifest themselves for
example in a strongly anisotropic resistivity tensor. We give a brief
introduction and overview of this new and emerging field.

</DOC>
<DOC>
<DOCNO> 10621 </DOCNO>
Geometry dependent dephasing in small metallic wires


  Temperature dependent weak localization is measured in metallic nanowires in
a previously unexplored size regime down to width $w=5$ nm. The dephasing time,
$\tau_{\phi}$, shows a low temperature $T$ dependence close to quasi-1D
theoretical expectations ($\tau_{\phi} \sim T^{-2/3}$) in the narrowest wires,
but exhibits a relative saturation as $T \to 0$ for wide samples of the same
material, as observed previously. As only sample geometry is varied to exhibit
both suppression and divergence of $\tau_{\phi}$, this finding provides a new
constraint on models of dephasing phenomena.

</DOC>
<DOC>
<DOCNO> 117553 </DOCNO>
CCD photometry in the region of NGC 6994: the remains of an old open


  We present the results of BV(RI)_KC CCD photometry down to V=21 mag in the
region of NGC 6994. To our knowledge, no photometry has previously been
reported for this object and we find evidences that it is a poor and sparse old
open cluster, with a minimum angular diameter of 9 arcmin, i.e. larger than the
3 arcmin originally assigned to it. We obtain a color excess E(B-V) = 0.07 +/-
0.02 mag by means of the BVI_(C) technique. Based on the theoretical isochrones
from VandenBergh (1985) that are in better agreement with our data, we estimate
for this cluster a distance from the Sun of 620 pc (Vo-Mv = 9 +/- 0.25 mag) and
an age lying within the range of 2 - 3 Gyr, adopting solar metallicity. Thus,
the corresponding cluster's Galactocentric distance is 8.1 kpc and is placed at
about 350 pc below the Galactic plane. According to this results, NGC 6994
belongs to the old open cluster population located in the outer disk and at
large distances from the Galactic plane, and must have suffered significant
individual dynamical evolution, resulting in mass segregation and evaporation
of low mass stars.

</DOC>
<DOC>
<DOCNO> 84146 </DOCNO>
On the gravitational moments of a Dirac particle


  We consider the classical theory of the Dirac massive particle in the
Riemann-Cartan spacetime. We demonstrate that the translational and the Lorentz
gravitational moments, obtained by means of the Gordon type decompositions of
the canonical energy-momentum and spin currents, are consistently coupled to
torsion and curvature, as expected.

</DOC>
<DOC>
<DOCNO> 117493 </DOCNO>
The discovery of photospheric nickel in the hot DO white dwarf


  We present the first evidence for the direct detection of nickel in the
photosphere of the hot DO white dwarf REJ0503$-$289. While this element has
been seen previously in the atmospheres of hot H-rich white dwarfs, this is one
of the first similar discoveries in a He-rich object. Intriguingly, iron, which
is observed to be more abundant than Ni in the hot DA stars, is not detected,
the upper limit to its abundance (Fe/He$=10^{-6}$) implying a Fe/Ni ratio a
factor 10 lower than seen in the H-rich objects (Ni/He$=10^{-5}$ for
REJ0503$-$289). The abundance of nickel and various other elements heavier than
He were determined from GHRS spectra. We used two completely independent sets
of NLTE model atmospheres which both provide the same results. This not only
reduces the possibility of systematic errors in our analysis but is also an
important consistency check for both model atmosphere codes.
  We have also developed a more objective method of determining $T_{\rm eff}$
and log g, from the He lines in the optical spectrum, in the form of a formal
fitting of the line profiles to a grid of model spectra, an analogue of the
standard procedure utilising the Balmer lines in DA white dwarfs. This gives
the assigned uncertainties in $T_{\rm eff}$ and log g a firm statistical basis
and allows us to demonstrate that inclusion of elements heavier than H, He and
C in the spectral calculations, exclusively considered in most published
optical analyses, yields a systematic downward shift in the measured value of
$T_{\rm eff}$.

</DOC>
<DOC>
<DOCNO> 69786 </DOCNO>
Using {\sc top-c} for Commodity Parallel Computing in Cosmic Ray Physics


  {\sc top-c} (Task Oriented Parallel C) is a freely available package for
parallel computing. It is designed to be easy to learn and to have good
tolerance for the high latencies that are common in commodity networks of
computers. It has been successfully used in a wide range of examples, providing
linear speedup with the number of computers. A brief overview of {\sc top-c} is
provided, along with recent experience with cosmic ray physics simulations.

</DOC>
<DOC>
<DOCNO> 9874 </DOCNO>
Spreading and annihilating particles: surprises from mean-field theory


  We study the pairwise annihilation process $A+A\to$ inert of a number of
random walkers, which originally are localized in a small region in space. The
size of the colony and the typical distance between particles increases with
time and, consequently, the reaction rate goes down. In the long time limit the
spatial density profile becomes scale invariant. The mean-field approximation
of this scenario bears some surprises. It predicts an upper critical dimension
$d_c=2$, with logarithmic corrections at the critical dimension and nontrivial
scaling behavior for d<2. Based on an exact solution of the one dimensional
system we conjecture that the mean-field {\it exponents} are in fact correct
even below the upper critical dimension, down to d=1, while the corresponding
scaling function that describes the spatial density profile, changes for d<2
due to the stochastic fluctuations.

</DOC>
<DOC>
<DOCNO> 70375 </DOCNO>
Distinct Hagedorn temperatures from particle spectra: a higher one for


  We analyze experimental particle spectra and show that the Hagedorn
temperature is significantly larger for mesons than for baryons. The effect can
be explained within dual string models: excitations of three strings in the
baryon produce ``faster'' combinatorics than a single string in the meson,
hence lead to a more rapid growth of baryons than mesons. Predictions of other
approaches for the gross features of particle spectra are also discussed.

</DOC>
<DOC>
<DOCNO> 151076 </DOCNO>
D-branes and Strings as Non-commutative Solitons


  The non-commutative geometry of a large auxiliary $B$-field simplifies the
construction of D-branes as solitons in open string field theory. Similarly,
fundamental strings are constructed as localized flux tubes in the string field
theory. Tensions are determined exactly using general properties of non-BPS
branes, and the non-Abelian structure of gauge fields on coincident D-branes is
recovered.

</DOC>
<DOC>
<DOCNO> 102883 </DOCNO>
Triality and Quantization of Singularities in Massive Fermion


  It is proved that fermions can acquire the mass through the additional
non-integrable exponential factor. For this propose the special vector
potential associated with the spinor field was introduced. Such a vector
potential has close relation with the triality property in Dirac spinors and
plays crucial role in the construction of massive term. It is shown that the
change in phase of a wavefunction round any closed curve with the possibility
of there being singularities in our vector potential will lead to the law of
quantization of physical constants including the mass. The triality properties
of Dirac's spinors are studied and it leads to a double covering vector
representation of Dirac spinor field. It is proved that massive Dirac equation
in the bosonic representation is self-dual.

</DOC>
<DOC>
<DOCNO> 13149 </DOCNO>
Exactly Solved Stochastic Directed Self-Organized Critical Models


  This paper has been withdrawn by the author, since one of the key results
duplicates existing work, as pointed out by a reader. I am currently revising
the manuscript.

</DOC>
<DOC>
<DOCNO> 8366 </DOCNO>
Finite Size Effects on Spin Glass Dynamics


  The recent identification of a time and temperature dependent spin glass
correlation length, $\xi({t_w},T)$, has consequences for samples of finite
size. Qualitative arguments are given on this basis for departures from t/{t_w}
scaling for the time decay of the thermoremanent magnetization,
{M_{TRM}}(t,{t_w},T), where t is the measurement time after a ``waiting time''
t_w, and for the imaginary part of the ac susceptibility,
${\chi^{{\prime}{\prime}}}(\omega,t)$. Consistency is obtained for a more rapid
decay of $M_{TRM}(t,{t_w},T)$ with increasing t_w when plotted as a function of
t/{t_w}, for the deviation of the characteristic time for {M_{TRM}}(t,{t_w},T)
from a linear dependence upon H^2 at larger values of H, and for the deviation
of the decay of ${\chi^{{\prime}{\prime}}}(\omega,t)$ from $\omega t$ scaling
upon a change in magnetic field at large values of $\omega t$. These departures
from scaling can, in principle, be used to extract the particle size
distribution for a given spin glass sample.

</DOC>
<DOC>
<DOCNO> 40474 </DOCNO>
News about nu's


  We review new results in neutrino physics, including the latest data of the
Super-Kamiokande, SNO and K2K experiments.

</DOC>
<DOC>
<DOCNO> 68372 </DOCNO>
Transverse Dynamics of Hard Partons in Nuclear Media and the QCD Dipole


  We derive the non-abelian generalization of the Furry approximation which
describes the transverse dynamical evolution of a hard projectile parton inside
a spatially extended colour target field. This provides a unified starting
point for the target rest frame description of the nuclear dependence of a
large class of observables. For the case of the virtual gamma -> q-qbar
photoabsorption cross section, we investigate then in detail under which
conditions the nuclear dependence encoded in the Furry wavefunctions can be
parametrized by a q-qbar QCD dipole cross section. The important condition is
colour triviality, i.e., the property that for arbitrary N-fold rescattering
contributions the only non-vanishing colour trace is N_c C_F^N. We give proofs
for the colour triviality of the inelastic, diffractive and total
photoabsorption cross section measured inclusively or with one jet resolved in
the final state. Also, we list examples for which colour interference effects
remain. Colour triviality allows us to write the gamma -> q qbar contribution
to the DIS nuclear structure function F_2 for small Bjorken x in terms of a
path integral which describes the transverse size evolution of the q-qbar pair
in the nuclear colour field. This expression reduces in an opacity expansion to
the N=1 result of Nikolaev and Zakharov, and in the eikonal approximation to
the Glauber-type rescattering formulas first derived by Mueller. In the
harmonic oscillator approximation of the path integral, we quantify deviations
from the eikonal limit. Their onset is characterized by the scales L/l_f and
E_t L which relate the longitudinal extension L of the nuclear target to the
coherence length l_f and the total transverse energy E_t accumulated by the
q-qbar pair.

</DOC>
<DOC>
<DOCNO> 151509 </DOCNO>
RR charges of D2-branes in the WZW model


  We consider the contribution of the B-field into the RR charge of a spherical
D2-brane. Extending a recent analysis of Taylor, we show that the boundary and
bulk contributions do not cancel in general. Instead, they add up to an integer
as observed by Stanciu. The general formula is applied to compute the RR
charges of spherical D-branes of the SU(2) WZW model at level k and it shows
that these RR charges are only defined modulo k+2. We support this claim by
studying bound state formation of D0-branes using boundary conformal field
theory.

</DOC>
<DOC>
<DOCNO> 117585 </DOCNO>
The MACHO Project: Microlensing Results from 5.7 Years of LMC


  We report on our search for microlensing towards the Large Magellanic Cloud
(LMC). Analysis of 5.7 years of photometry on 11.9 million stars in the LMC
reveals 13 - 17 microlensing events. This is significantly more than the $\sim$
2 to 4 events expected from lensing by known stellar populations. The
timescales ($\that$) of the events range from 34 to 230 days. We estimate the
microlensing optical depth towards the LMC from events with $2 < \that < 400$
days to be 1.2 ^{+0.4}_ {-0.3} \ten{-7}$, with an additional 20% to 30% of
systematic error. The spatial distribution of events is mildly inconsistent
with LMC/LMC disk self-lensing, but is consistent with an extended lens
distribution such as a Milky Way or LMC halo. Interpreted in the context of a
Galactic dark matter halo, consisting partially of compact objects, a maximum
likelihood analysis gives a MACHO halo fraction of 20% for a typical halo model
with a 95% confidence interval of 8% to 50%. A 100% MACHO halo is ruled out at
the 95% C.L. for all except our most extreme halo model. Interpreted as a
Galactic halo population, the most likely MACHO mass is between $ 0.15 \msun$
and $ 0.9 \msun$, depending on the halo model, and the total mass in MACHOs out
to 50 kpc is found to be 9+4-3 10^{10} msun, independent of the halo model.
These results are marginally consistent with our previous results, but are
lower by about a factor of two. Besides a larger data set, this work also
includes an improved efficiency determination, improved likelihood analysis,
and more thorough testing of systematic errors, especially with respect to the
treatment of potential backgrounds to microlensing, such as supernovae in
galaxies behind the LMC. [Abridged]

</DOC>
<DOC>
<DOCNO> 8564 </DOCNO>
The effect of Hund's Coupling on one-dimensional Luttinger Liquids


  Two one-dimensional Luttinger liquid systems coupled by Hund's coupling are
studied by the renormalization group and the non-abelian bosonization methods.
It is found that the Hund's coupling is always relevant irrespective of the
repulsive interaction between electrons within each chain.
 The properties of the resulting strong coupling fixed point are discussed.

</DOC>
<DOC>
<DOCNO> 85402 </DOCNO>
EinS: a Mathematica package for computations with indexed objects


  This preprint contains a description of a package for Mathematica called
EinS. This package allows one to perform various calculations with indexed
objects.

</DOC>
<DOC>
<DOCNO> 169883 </DOCNO>
The finite difference algorithm for higher order supersymmetry


  The higher order supersymmetric partners of the Schroedinger's Hamiltonians
can be explicitly constructed by iterating a simple finite difference equation
corresponding to the Baecklund transformation. The method can completely
replace the Crum determinants. Its limiting, differential case offers some new
operational advantages.

</DOC>
<DOC>
<DOCNO> 121533 </DOCNO>
Dynamical and content evolution of a sample of clusters from z~0 to


  In this paper, we present an analysis of the dynamics and segregation of
galaxies in rich clusters from z~0.32 to z~0.48 taken from the CFHT Optical
PDCS (COP) survey and from the CNOC survey (Carlberg et al. 1997). Our results
from the COP survey are based upon the recent observational work of Adami et
al. (2000) and Holden et al. (2000) and use new spectroscopic and photometric
data on six clusters selected from the Palomar Distant Cluster Survey (PDCS;
Postman et al. 1996). We have compared the COP and CNOC samples to the ESO
Nearby Abell Cluster Survey (ENACS: z~0.07). Our sample shows that the z<0.4
clusters have the same velocity dispersion versus magnitude, morphological type
and radius relationships as nearby Abell clusters. The z~0.48 clusters exhibit,
however, departures from these relations. Furthermore, there appears to be a
higher fraction of late-type (or bluer, e.g. Butcher and Oemler, 1984) galaxies
in the distant clusters compared to the nearby ones. The classical scenario in
which massive galaxies virialize before they evolve from late into early type
explain our observations. In such a scenario, the clusters of our sample began
to form before a redshift of ~0.8 and the late-type galaxy population had a
continuous infall into the clusters.

</DOC>
<DOC>
<DOCNO> 170255 </DOCNO>
Large-Angle, Single-Order, One and Two-Dimensional Atomic Interferometry


  We have shown via explicit analysis as well as numerical simulation the
design of two large angle interferometers employing two-photon pulses. The
first one uses the technique of adiabatic following in a dark state to produce
a large splitting angle atomic interferometer that is capable of producing one
dimensional gratings with spacings as small as 2 nm. Unlike other large angle
interferometers, this technique is not sensitive to errors in optical pulse
area and decoherence from excited state decay. This may lead to a nearly two
orders of magnitude improvement in the sensitivity of devices such as atomic
gyroscopes, which are already as good as the best laser gyroscopes. The second
interferometer uses the technique of Raman pulses to produce a two-dimensional
interferometer, with independent choice of grating spacings in each direction,
each being as small as 2 nm. This scheme may enable one to produce uniform
arrays of quantum dots with dimensions of only a few nm on each side. In
addition, it may be possible to generalize this process to produce arbitrary
patterns with the same type of resolution.

</DOC>
<DOC>
<DOCNO> 13424 </DOCNO>
Semiclassical Concepts in Magnetoelectronics


  Semiclassical theories of electron and spin transport in metallic magnetic
structures are reviewed with emphasis on the role of disorder and electronic
band structures in the current perpendicular to the interface plane (CPP)
transport configuration.

</DOC>
<DOC>
<DOCNO> 151610 </DOCNO>
Tachyon condensation in the D0/D4 system


  The D0/D4 system with a Neveu-Schwarz B-field in the spatial directions of
the D4-brane has a tachyon in the spectrum of the (0,4) strings. The tachyon
signals the instability of the system to form a bound state of the D0-brane
with the D4-brane. We use the Wess-Zumino-Witten like open superstring field
theory formulated by Berkovits to study the tachyon potential for this system.
The tachyon potential lies outside the universality class of the D-brane
anti-D-brane system. It is a function of the B-field. We calculate the tachyon
potential at the zeroth level approximation. The minimum of the tachyon
potential in this case is expected to reproduce the mass defect involved in the
formation of the D0/D4 bound state. We compare the minimum of the tachyon
potential with the mass defect in three cases. For small values of the B-field
we obtain 70% of the expected mass defect. For large values of the B-field with
Pf$(2\pi\alpha' B) >0$ the potential reduces to that of the D-brane
anti-D-brane reproducing 62% of the expected mass defect. For large values of
the B-field with Pf$(2\pi\alpha' B) <0$ the minimum of the tachyon potential
gives 25% of the expected mass defect. At the tachyon condensate we show that
the (0,4) strings decouple from the low energy dynamics.

</DOC>
<DOC>
<DOCNO> 39871 </DOCNO>
Unity of Fundamental Interactions


  The vector representation of the linearized gravitational field (the graviton
field) or the so called quantum gravitodynamics which describes the motion of
masses in a weak gravitational field is employed to understand the unity of the
four known interactions. We propose a gauge group SU(3)xSU(2)xU(1)xU(1) for
such a unified field theory. In this paper we study the SU(2)xU(1)xU(1) sector
of the theory and in analogy to the electroweak mixing angle we define a
gravitoweak mixing angle. The unified gauge field theory predicts the existence
of three massive vector bosons, the Y+/- and the X^0. and two massless vector
bosons, the photon and the graviton (in its vector representation). We
determine the mass spectrum of the Y+/- and the X^0 and predict a modification
to the fine structure constant under unified field conditions. Furthermore, we
briefly discuss the implications of the extended object formulation for the
gauge hierarchy problem.

</DOC>
<DOC>
<DOCNO> 71488 </DOCNO>
Phenomenology of Higgs bosons in the Zee-Model


  To generate small neutrino masses radiatively, the Zee-model introduces two
Higgs doublets and one weak-singlet charged Higgs boson to its Higgs sector.
  From analyzing the renormalization group equations, we determine the
possibile range of the lightest CP-even Higgs boson ($h$) mass and the Higgs
boson self-couplings as a function of the cut-off scale beyond which either
some of the coupling constants are strong enough to invalidate the perturbative
analysis or the stability of the electroweak vacuum is no longer guaranteed.
Using the results obtained from the above analysis, we find that the singlet
charged Higgs boson can significantly modify the partial decay width of $h \to
\gamma \gamma$ via radiative corrections, and its collider phenomenology can
also be drastically different from that of the charged Higgs bosons in the
usual two-Higgs-doublet models.

</DOC>
<DOC>
<DOCNO> 70739 </DOCNO>
Particle Rapidity Density Saturation in Heavy Ion Collisions and the


  We show that the Dual String Model with fusion leads, in heavy ion
collisions, to strict saturation of the particle (pseudo-)rapidity density,
normalised to the number of participant nucleons, as that number increases.
Asymptotically, as the centre-of-mass energy goes to infinity with the number
of participants fixed, this density approaches the nucleon-nucleon density.
  A comparison with recent WA98 data is presented.

</DOC>
<DOC>
<DOCNO> 117564 </DOCNO>
A Unified Scaling Law in Spiral Galaxies


  We investigate the origin of a unified scaling relation in spiral galaxies.
Observed spiral galaxies are spread on a plane in the
three-dimensionallogarithmic space of luminosity L, radius R and rotation
velocity V. The plane is expressed as $L \propto (V R)^{\alpha}$ in I-passband,
where $\alpha$ is a constant. On the plane, observed galaxies are distributed
in an elongated region which looks like the shape of a surfboard. The
well-known scaling relations, L-V (Tully-Fisher relation), V-R (also the
Tully-Fisher relation) and R-L (Freeman's law), can be understood as oblique
projections of the surfboard-like plane into 2-D spaces. This unified
interpretation of the known scaling relations should be a clue to understand
the physical origin of all the relations consistently. Furthermore, this
interpretation can also explain why previous studies could not find any
correlation between TF residuals and radius.
  In order to clarify the origin of this plane, we simulate formation and
evolution of spiral galaxies with the N-body/SPH method, including cooling,
star formation and stellar feedback. Initial conditions are set to isolated 14
spheres with two free parameters, such as mass and angular momentum. The CDM
(h=0.5, $\Omega_0=1$) cosmology is considered as a test case. The simulations
provide the following two conclusions: (a) The slope of the plane is well
reproduced but the zero-point is not. This zero-point discrepancy could be
solved in a low density ($\Omega_0<1$) and high expansion (h>0.5) cosmology.
(b) The surfboard-shaped plane can be explained by the control of galactic mass
and angular momentum.

</DOC>
<DOC>
<DOCNO> 71531 </DOCNO>
Highlights of CP 2000


  Various developing topics in CP violation are reviewed. There are many
theoretical reasons to hope that the CKM paradigm may be incomplete. It is
surely too soon to be claiming new physics in \epsilon^\prime/\epsilon or in
D^0-\bar D^0 mixing, but rare K decays offer interesting places to search for
new physics. It is probably also premature to see a clash between global CKM
fits and current estimates of sin \beta and \gamma, where much more precise
data will soon be available. There are interesting possibilities to look for CP
violation in neutrino oscillations and in Higgs physics. Rapid progress can be
expected now that CP violation is moving to the top of the particle physics
agenda.

</DOC>
<DOC>
<DOCNO> 84743 </DOCNO>
Translational Chern--Simons Action and New Planar Particle Dynamics


  We consider a nonstandard $D=2+1$ gravity described by a translational
Chern--Simons action, and couple it to the nonrelativistic point particles. We
fix the asymptotic coordinate transformations in such a way that the space part
of the metric becomes asymptotically Euclidean. The residual symmetries are
(local in time) translations and rigid rotations. The phase space Hamiltonian
$H$ describing two-body interactions satisfies a nonlinear equation $H={\cal
H}(\vec{x},\vec{p};H)$ what implies, after quantization, a nonstandard form of
the Schr\"{o}dinger equation with energy-dependent fractional angular momentum
eigenvalues. Quantum solutions of the two-body problem are discussed. The bound
states with discrete energy levels correspond to a confined classical motion
(for the planar distance between two particles $r\leq r_0$) and the scattering
states with continuous energy correspond to classical motion for $r>r_0$.

</DOC>
<DOC>
<DOCNO> 120840 </DOCNO>
Afterglows from jetted GRB remnants


  We have found that the conventional generic dynamical model for gamma-ray
bursts (GRBs) cannot reproduce the Sedov solution in the non-relativistic
limit. Based on our refined generic dynamical model, we investigate afterglows
from jetted GRB remnants numerically. Many new results are reached. For
example, we find no obvious break in the optical light curve during the
relativistic phase itself. But an obvious break does exist at the transition
from the relativistic phase to the non-relativistic phase, which typically
occurs at time 10 to 30 days. It is very interesting that the break is affected
by many parameters, such as the electron energy fraction, $\xi_{\rm e}$, the
magnetic energy fraction, $\xi_{\rm B}^2$, the initial opening angle of the
jet,$\theta_0$, and the medium density, $n$. We also find that afterglows from
jetted GRB remnants are uniformly characterized by a quick decay during the
non-relativistic phase, with power law timing index greater than 2.1 .
Afterglows from GRB 970228, 980326, 980519, 990123, 990510 and 991208 can be
satisfactorily fitted if the corresponding GRB ejecta are highly collimated.

</DOC>
<DOC>
<DOCNO> 10337 </DOCNO>
Spin Susceptibility and Specific Heat in the d-p Model


  We analyze the two-dimensional {\it d-p} model, considering both
antiferromagnetic spin fluctuation and $d_{x^2-y^2}$-wave superconducting
fluctuation. We adopt the fluctuation-exchange approximation in order to derive
both normal and anomalous vertices composed only of the renormalized {\it
d}-electron Green function and the on-site repulsive interaction among the {\it
d}-electrons. Using these vertices, we derive a $t$-matrix as a superconducting
fluctuation propagator. Then, we obtain self-consistent solutions in which the
system is close to antiferromagnetic instability. In our solutions, the
superconducting fluctuation couples strongly with the quasiparticle state and
this causes the anomalous behavior in the temperature dependences of spin
susceptibility and specific heat.

</DOC>
<DOC>
<DOCNO> 119897 </DOCNO>
Hubble Space Telescope Imaging of the Circinus Galaxy


  We present an HST imaging study of the nearby (4 Mpc distant) Circinus
galaxy, which contains the nearest type 2 Seyfert nucleus and prominent
circumnuclear star formation. Images have been obtained in the
[OIII]$\lambda$5007, H$\alpha$ and H$_2$ v=1--0 S(1) emission lines, and in the
green (5470 \AA), red (8140 \AA) and near infrared (2.04 and 2.15 $\mu$m)
continua. An image in the [Fe II] $\lambda$1.644 $\mu$m line has been taken
with a ground-based telescope. The [OIII] and H$\alpha$ images reveal the
detailed structure of the complex of streamers and knots of high-excitation
gas, which extends out of the galaxy disk. The morphology some 250 pc from the
nucleus strongly suggests that the high-excitation gas is concentrated on the
surface of a hollow cone with apex close to the nucleus. Such a structure may
result through entrainment of dense gas from a circumnuclear torus in the
galaxy disk by a low density, outflowing wind or jet. Within 40 pc of the
nucleus, the high-excitation gas takes the form of a striking, filled V-shaped
structure extending in the same direction as the larger scale high-excitation
emission. This `V' can be described as an ionization cone, though a
matter-bounded structure is also possible. The implied collimation of the
ionizing photons or gaseous outflow must occur within 2 pc of the apex of the
cone, presumed to be the location of the nucleus. The H$\alpha$ image shows a
complex structure of HII regions, including the well known starburst ring of
radius 150 - 270 pc. In addition, there is a more compact (40 pc radius),
elliptical ring of HII regions around the `ionization cone'. We argue that this
latter ring, which we call the nuclear ring, is intrinsically circular and
located in the plane of the galaxy disk. Abstract truncated.

</DOC>
<DOC>
<DOCNO> 84448 </DOCNO>
Gauge Symmetry and Gravito-Electromagnetism


  A tensor description of perturbative Einsteinian gravity about an arbitrary
background spacetime is developed. By analogy with the covariant laws of
electromagnetism in spacetime, gravito-electromagnetic potentials and fields
are defined to emulate electromagnetic gauge transformations under
substitutions belonging to the gauge symmetry group of perturbative
gravitation. These definitions have the advantage that on a flat background,
with the aid of a covariantly constant timelike vector field, a subset of the
linearised gravitational field equations can be written in a form that is fully
analogous to Maxwell's equations (without awkward factors of 4 and extraneous
tensor fields). It is shown how the remaining equations in the perturbed
gravitational system restrict the time dependence of solutions to these
equations and thereby prohibit the existence of propagating vector fields. The
induced gravito-electromagnetic Lorentz force on a test particle is evaluated
in terms of these fields together with the torque on a small gyroscope. It is
concluded that the analogy of perturbative gravity to Maxwell's description of
electromagnetism can be valuable for (quasi-)stationary gravitational phenomena
but that the analogy has its limitations.

</DOC>
<DOC>
<DOCNO> 120059 </DOCNO>
Afterglow Emission from Naked Gamma-Ray Bursts


  We calculate the {\it afterglow} emission for Gamma-Ray Bursts (GRBs) going
off in an extremely low density medium, referred to as {\it naked bursts}. Our
results also apply to the case where the external medium density falls off
sharply at some distance from the burst. The observed afterglow flux in this
case originates at high latitudes, i.e. where the angle between the fluid
velocity and the observer line of sight is greater than $\Gamma^{-1}$. The
observed peak frequency of the spectrum for naked bursts decreases with
observer time as $t^{-1}$, and the flux at the peak of the spectrum falls off
as $t^{-2}$. The 2--10 keV $X$-ray flux from a naked burst of average fluence
should be observable by the SWIFT satellite for time duration of about $10^3$
longer than the burst variability timescale. The high latitude emission
contributes to the early $X$-ray afterglow flux for any GRB, not just naked
bursts, and can be separated from the shocked inter-stellar medium (ISM)
emission by their different spectral and temporal properties. Measurements of
the high latitude emission could be used to map the angular structure of GRB
producing shells.

</DOC>
<DOC>
<DOCNO> 150750 </DOCNO>
Topological Symmetries


  We introduce the notion of a topological symmetry as a quantum mechanical
symmetry involving a certain topological invariant. We obtain the underlying
algebraic structure of the Z_2-graded uniform topological symmetries of type
(1,1) and (2,1). This leads to a novel derivation of the algebras of
supersymmetry and $p=2$ parasupersummetry.

</DOC>
<DOC>
<DOCNO> 120190 </DOCNO>
Chemical composition of evolved stars in the open cluster M 67


  High-resolution spectra of six core helium-burning `clump' stars and three
giants in the open cluster M 67 have been obtained with the SOFIN spectrograph
on the Nordic Optical Telescope to investigate abundances of up to 25 chemical
elements. Abundances of carbon were studied using the C2 Swan (0,1) band head
at 5635.5 A. The wavelength interval 7980-8130 A with strong CN features was
analysed in order to determine nitrogen abundances and 12C/13C isotope ratios.
The oxygen abundances were determined from the [O I] line at 6300 A.
  The overall metallicity of the cluster stars was found to be close to solar
([Fe/H]=-0.03+-0.03). Compared with the Sun and other dwarf stars of the
Galactic disk, as well as with dwarf stars of M 67 itself, abundances in the
investigated stars suggest that carbon is depleted by about 0.2 dex, nitrogen
is enhanced by about 0.2 dex and oxygen is unaltered. Among other mixing-
sensitive chemical elements an overabundance of sodium may be suspected. The
mean C/N and 12C/13C ratios are lowered to the values of 1.7+-0.2 and 24+-4 in
the giants and to the values of 1.4+-0.2 and 16+-4 in the clump stars. These
results suggest that extra mixing of CN-cycled material to the stellar surface
takes place after the He-core flash. Abundances of heavy chemical elements in
all nine stars were found to be almost identical and close to solar.

</DOC>
<DOC>
<DOCNO> 69463 </DOCNO>
Exclusive Hadronic D Decays to $\eta'$ or $\eta$: Addendum on Resonant


  For hadronic two-body decays of charmed mesons involving $\eta$ or $\eta'$,
resonance-induced final-state interactions (FSI) that mimic the W-exchange or
the W-annihilation topology can play an essential role. In particular, the
decays $D^0\to\bar K^0\eta'$ and $D^+\to\pi^+\eta$, which are largely
suppressed in the absence of FSI, are enhanced dramatically by resonant FSI. It
is stressed that the effect of resonant FSI is negligible for
$\rho^+(\eta,\eta')$ final states because of the mismatch of the G parity of
$\rho^+(\eta,\eta')$ and the J=0, I=1 meson resonance. We argue that a possible
gluon-mediated process in which two gluons couple directly to the gluonic
component of the $\eta'$, e.g. the gluonium, rather than to the flavor-singlet
$\eta_0$, can enhance both modes $D_s^+\to\rho^+\eta'$ and
$D_s^+\to\rho^+\eta$, especially the former; that is, this new mechanism can
account for the unexpectedly large branching ratio of $\rho^+\eta'$ without
suppressing $\rho^+\eta$.

</DOC>
<DOC>
<DOCNO> 84362 </DOCNO>
Making use of geometrical invariants in black hole collisions


  We consider curvature invariants in the context of black hole collision
simulations. In particular, we propose a simple and elegant combination of the
Weyl invariants I and J, the {\sl speciality index} ${\cal S}$. In the context
of black hole perturbations $\cal S$ provides a measure of the size of the
distortions from an ideal Kerr black hole spacetime. Explicit calculations in
well-known examples of axisymmetric black hole collisions demonstrate that this
quantity may serve as a useful tool for predicting in which cases perturbative
dynamics provide an accurate estimate of the radiation waveform and energy.
This makes ${\cal S}$ particularly suited to studying the transition from
nonlinear to linear dynamics and for invariant interpretation of numerical
results.

</DOC>
<DOC>
<DOCNO> 117254 </DOCNO>
Logarithmic two-loop corrections to the Lamb shift in hydrogen


  Higher order $(\alpha/\pi)^2 (Z \alpha)^6$ logarithmic corrections to the
hydrogen Lamb shift are calculated. The results obtained show the two-loop
contribution has a very peculiar behavior, and significantly alter the
theoretical predictions for low lying S-states.

</DOC>
<DOC>
<DOCNO> 10028 </DOCNO>
Aging and Non Linear Glassy Dynamics in a Mean-Field Model


  The mean-field dynamics of a particle in a random, but short range correlated
potential, offers the opportunity of observing both aging and driven stationary
regimes. Using a geometrical approach previously introduced by the author, we
study here the relation between these two situations, in the pure relaxational
limit, i.e. the zero temperature case. In the stationary regime, the
velocity(v) -force(f) characteristics is a power law, while the characteristic
times scale like powers of v, in agreement with an early proposal by Horner.
The cross-over between the aging, linear-response regime and the non linear
stationary regime is smooth, and we propose a parametrisation of the
correlation functions valid in both cases, by means of an "effective time". We
conclude that aging and non linear response are dual manifestations of a single
out-of-equilibrium state, which might be a generic situation.

</DOC>
<DOC>
<DOCNO> 174538 </DOCNO>
Stability and instability of a hot and dilute nuclear droplet


  The diabatic approach to collective nuclear motion is reformulated in the
local-density approximation in order to treat the normal modes of a spherical
nuclear droplet analytically. In a first application the adiabatic isoscalar
modes are studied and results for the eigenvalues of compressional (bulk) and
pure surface modes are presented as function of density and temperature inside
the droplet, as well as for different mass numbers and for soft and stiff
equations of state. We find that the region of bulk instabilities (spinodal
regime) is substantially smaller for nuclear droplets than for infinite nuclear
matter. For small densities below 30% of normal nuclear matter density and for
temperatures below 5 MeV all relevant bulk modes become unstable with the same
growth rates. The surface modes have a larger spinodal region, reaching out to
densities and temperatures way beyond the spinodal line for bulk instabilities.
Essential experimental features of multifragmentation, like fragmentation
temperatures and fragment-mass distributions (in particular the power-law
behavior) are consistent with the instability properties of an expanding
nuclear droplet, and hence with a dynamical fragmentation process within the
spinodal regime of bulk and surface modes (spinodal decomposition).

</DOC>
<DOC>
<DOCNO> 7682 </DOCNO>
Concentration-Pressure phase diagram for rich Zr PZT ceramics


  This work reports on the systematic high pressure Raman studies in the
PbZr$_{1-x}$Ti$_x$O$_3$ ($0.02 \leq x \leq 0.14$) ceramics performed at room
temperature. The pressure dependence of the Raman spectra reveals the stable
phases of the material under pressure variation. The results allowed us to
propose a concentration-pressure phase diagram for rich Zr PZT system up to
pressures of 5.0 GPa.

</DOC>
<DOC>
<DOCNO> 70180 </DOCNO>
Measurements of the $Q^2$-Dependence of the Proton and Neutron Spin


  The structure functions g1p and g1n have been measured over the range 0.014 <
x < 0.9 and 1 < Q2 < 40 GeV2 using deep-inelastic scattering of 48 GeV
longitudinally polarized electrons from polarized protons and deuterons. We
find that the Q2 dependence of g1p (g1n) at fixed x is very similar to that of
the spin-averaged structure function F1p (F1n). From a NLO QCD fit to all
available data we find $\Gamma_1^p - \Gamma_1^n =0.176 \pm 0.003 \pm 0.007$ at
Q2=5 GeV2, in agreement with the Bjorken sum rule prediction of 0.182 \pm
0.005.

</DOC>
<DOC>
<DOCNO> 120004 </DOCNO>
Abundances and Kinematics of Field Halo and Disk Stars I: Observational


  We describe observations and abundance analysis of a high-resolution,
high-S/N survey of 168 stars, most of which are metal-poor dwarfs. We follow a
self-consistent LTE analysis technique to determine the stellar parameters and
abundances, and estimate the effects of random and systematic uncertainties on
the resulting abundances. Element-to-iron ratios are derived for key alpha,
odd, Fe-peak, r- and s-process elements. Effects of Non-LTE on the analysis of
Fe I lines are shown to be very small on the average. Spectroscopically
determined surface gravities are derived that are generally close to those
obtained from Hipparcos parallaxes.

</DOC>
<DOC>
<DOCNO> 170072 </DOCNO>
A counterexample to a conjectured entanglement inequality


  We give an explicit counterexample to an entanglement inequality suggested in
a recent paper [quant-ph/0005126] by Benatti and Narnhofer. The inequality
would have had far-reaching consequences, including the additivity of the
entanglement of formation.

</DOC>
<DOC>
<DOCNO> 83125 </DOCNO>
Optimal Belief Revision


  We propose a new approach to belief revision that provides a way to change
knowledge bases with a minimum of effort. We call this way of revising belief
states optimal belief revision. Our revision method gives special attention to
the fact that most belief revision processes are directed to a specific
informational objective. This approach to belief change is founded on notions
such as optimal context and accessibility. For the sentential model of belief
states we provide both a formal description of contexts as sub-theories
determined by three parameters and a method to construct contexts. Next, we
introduce an accessibility ordering for belief sets, which we then use for
selecting the best (optimal) contexts with respect to the processing effort
involved in the revision. Then, for finitely axiomatizable knowledge bases, we
characterize a finite accessibility ranking from which the accessibility
ordering for the entire base is generated and show how to determine the ranking
of an arbitrary sentence in the language. Finally, we define the adjustment of
the accessibility ranking of a revised base of a belief set.

</DOC>
<DOC>
<DOCNO> 119919 </DOCNO>
Cosmological Parameters from Velocities, CMB and Supernovae


  We compare and combine likelihood functions of the cosmological parameters
Omega_m, h and sigma_8, from peculiar velocities, CMB and type Ia supernovae.
These three data sets directly probe the mass in the Universe, without the need
to relate the galaxy distribution to the underlying mass via a "biasing"
relation. We include the recent results from the CMB experiments BOOMERANG and
MAXIMA-1. Our analysis assumes a flat Lambda CDM cosmology with a
scale-invariant adiabatic initial power spectrum and baryonic fraction as
inferred from big-bang nucleosynthesis. We find that all three data sets agree
well, overlapping significantly at the 2 sigma level. This therefore justifies
a joint analysis, in which we find a joint best fit point and 95 per cent
confidence limits of Omega_m=0.28 (0.17,0.39), h=0.74 (0.64,0.86), and
sigma_8=1.17 (0.98,1.37). In terms of the natural parameter combinations for
these data sigma_8 Omega_m^0.6 = 0.54 (0.40,0.73), Omega_m h = 0.21
(0.16,0.27). Also for the best fit point, Q_rms-ps = 19.7 muK and the age of
the universe is 13.2 Gyr.

</DOC>
<DOC>
<DOCNO> 121479 </DOCNO>
Temperature and Heavy Element Abundance Profiles of Cool Clusters of


  We perform a spatially resolved X-ray spectroscopic study of a set of 18
relaxed clusters of galaxies with gas temperatures below 4 keV. Spectral
analysis was done using ASCA/SIS data coupled with the spatial information
contained in ROSAT/PSPC and Einstein/IPC observations. We derive the
temperature profiles using single-temperature fits and also correct for the
presence of cold gas at the cluster centers. For all of the clusters in the
sample, we derive Si and Fe abundance profiles. For a few of the clusters, we
also derive Ne and S abundance profiles. We present a comparison of the
elemental abundances derived at similar overdensities as well as element
mass-to-light ratios. We conclude that the preferential accretion of low
entropy, low abundance gas into the potentials of groups and cold clusters can
explain most of the observed trends in metallicity. In addition, we discuss the
importance of energy input from SNe II on cluster scaling relations and on the
relation between the observed scatter in the retainment of SN Ia products with
differences between the epoch of cluster formation.

</DOC>
<DOC>
<DOCNO> 12940 </DOCNO>
Eliminating leading corrections to scaling in the 3-dimensional


  We study corrections to scaling in the O(3)- and O(4)-symmetric phi^4 model
on the three-dimensional simple cubic lattice with nearest neighbour
interactions. For this purpose, we use Monte Carlo simulations in connection
with a finite size scaling method. We find that there exists a finite value of
the coupling lambda^*, for both values of N, where leading corrections to
scaling vanish. As a first application, we compute the critical exponents
nu=0.710(2) and eta=0.0380(10) for N=3 and nu=0.749(2) and eta=0.0365(10) for
N=4.

</DOC>
<DOC>
<DOCNO> 99552 </DOCNO>
The toric cobordisms


  A smooth closed 3-manifold $M$ fibered by tori $T^2$ is characterized by an
element $\phi \in GL(2,\mathbb{Z})$. We show that $M$ is the boundary of a
4-manifold fibered by tori over a surface such that the bundle structure on $M$
is the restriction of the bundle structure on the 4-manifold if and only if
$\phi$ is from the commutator subgroup $(GL(2,\mathbb{Z}))'$. The notions of
oriented and unoriented cobordisms in the class of closed 3-manifolds fibered
by tori are introduced. It turns out that in this case the cobordisms form a
group, namely $\mathbb{Z}_{12}$ in the oriented case and
$\mathbb{Z}_{2}\oplus\mathbb{Z}_{2}$ in the unoriented one. When the surface on
the base of oriented cobordism is orientable, it is shown that its minimal
genus can be calculated by Culler's algorithm.

</DOC>
<DOC>
<DOCNO> 10267 </DOCNO>
Optimizing the classical heat engine


  A pair of systems at different temperatures is a classic environment for a
heat engine, which produces work during the relaxation to a common equilibrium.
It is generally believed that a direct interaction between the two systems will
always decrease the amount of the obtainable work, due to inevitable
dissipation. Here a situation is reported where, in some time window, work can
be gained due the direct coupling, while dissipation is relevant only for much
larger times. Thus, the amount of extracted work increases, at the cost of a
change of the final state.

</DOC>
<DOC>
<DOCNO> 8155 </DOCNO>
Trapped Bose-condensate in gravity field


  The 1D and 2D Bose-condensation of trapped atoms in a gravitational field are
considered. The deformation of the finite parabolic potential in this field is
modeling via the combination of two rectangular 1D and 2D traps, for which the
cut-off and the re-definition of spectrum are taken into account. A
Bose-condensation T_c shift by the gravity is calculated. A sign and a
magnitude of it in a deformed trap depends on the order of including the
gravitational field. The special choice of this order may describe three
consistent Bose-condensations with different temperatures. These transitions
may be associated with a transportation of a trap on the cycle (I) Earth-(II)
Space-(III) Earth.

</DOC>
<DOC>
<DOCNO> 12167 </DOCNO>
Microscopic Spectrum of the QCD Dirac Operator in Three Dimensions


  The microscopic spectral correlators of the Dirac operator in
three-dimensional Yang-Mills theory coupled to fundamental fermions and with
three or more colours are derived from the supersymmetric formulation of
partially quenched effective Lagrangians. The flavour supersymmetry breaking
patterns are appropriately identified and used to calculate the corresponding
finite volume partition functions from Itzykson-Zuber type integrals over
supersymmetric cosets. New and simple determinant expressions for the spectral
correlators in the mesoscopic scaling region are thereby found. The microscopic
spectrum derived from the effective finite volume partition function of
three-dimensional QCD agrees with earlier results based on the unitary ensemble
of random matrix theory and extends the corresponding calculations for QCD in
four dimensions.

</DOC>
<DOC>
<DOCNO> 12838 </DOCNO>
Modelling static impurities


  A simple model is presented for the calculation of the quenched average over
impurities which are rendered static by setting their mass equal to infinity.
The path integral formalism of the second quantized theory contains annealed
averages only. The similarity with the Gaussian quenched potential model is
discussed.

</DOC>
<DOC>
<DOCNO> 99673 </DOCNO>
From Dixmier algebras to Star Products


  Let M be a Galois cover of a nilpotent coadjoint orbit of a complex
semisimple Lie group. We define the notion of a PERFECT Dixmier algebra for M
and show how this produces a graded (non-local) equivariant star product on M
with several very nice properties. This is part of a larger program we have
been developing for working out the orbit method for nilpotent orbits.

</DOC>
<DOC>
<DOCNO> 68174 </DOCNO>
CP,T and/or CPT Violations in the K0-K0bar System --Implications of the


  Possible violation of CP, T and/or CPT symmetries in the $\ko$-$\kob$ system
is studied from a phenomenological point of view. For this purpose, we first
introduce parameters which represent violation of these symmetries in mixing
parameters and decay amplitudes in a convenient and well-defined way and,
treating these parameters as small, derive formulas which relate them to the
experimentally measured quantities. We then perform numerical analyses, with
the aid of the Bell-Steinberger relation, to derive constraints to these
symmetry-violating parameters, firstly paying particular attention to the
results reported by KTeV Collaboration and NA48 Collaboration, and then with
the results reported by CPLEAR Collaboration as well taken into account. A case
study, in which either CPT symmetry or T symmetry is assumed, is also carried
out. It is demonstrated that CP and T symmetries are violated definitively at
the level of 10^{-4} in $2\pi$ decays and presumably at the level of 10^{-3} in
the $\ko-\kob$ mixing, and that the Bell-Steinberger relation helps us to
establish CP and T violations being definitively present in the $\ko-\kob$
mixing and to test CPT symmetry to a level of 10^{-4} ~ 10^{-5}.

</DOC>
<DOC>
<DOCNO> 40152 </DOCNO>
Event Shapes and Power Corrections in ep DIS at HERA


  Deep-inelastic ep scattering data, taken with the H1 and ZEUS detectors at
HERA, are used to study the means and distributions of the event shape
variables thrust, jet broadening, jet mass, C-parameter and two kinds of
differential two-jet rate. The data cover a range of the four-momentum transfer
Q, taken to be the relevant energy scale, between 7 GeV and 141 GeV. The Q
dependences are compared with second-order calculations of perturbative QCD.
Power law corrections are applied to account for hadronization effects.

</DOC>
<DOC>
<DOCNO> 122664 </DOCNO>
Starbursts versus Truncated Star Formation in Nearby Clusters of


  We present long-slit spectroscopy, B and R bandpass imaging, and 21 cm
observations of a sample of early-type galaxies in nearby clusters which are
known to be either in a star-forming phase or to have had star formation which
recently terminated. From the long-slit spectra, obtained with the Blanco 4-m
telescope, we find that emission lines in the star-forming cluster galaxies are
significantly more centrally concentrated than in a sample of field galaxies.
The broadband imaging reveals that two currently star-forming early-type
galaxies in the Pegasus I cluster have blue nuclei, again indicating that
recent star formation has been concentrated. In contrast, the two galaxies for
which star formation has already ended show no central color gradient. The
Pegasus I galaxy with the most evident signs of ongoing star formation
(NGC7648), exhibits signatures of a tidal encounter. Neutral hydrogen
observations of that galaxy with the Arecibo radiotelescope reveal the presence
of ~4 x 10^8 solar masses of HI. Arecibo observations of other current or
recent star-forming early-type galaxies in Pegasus I indicate smaller amounts
of gas in one of them, and only upper limits in others.

</DOC>
<DOC>
<DOCNO> 99641 </DOCNO>
Riemannian Manifolds With Uniformly Bounded Eigenfunctions


  The standard eigenfunctions $\phi_{\lambda} = e^{i < \lambda, x >}$ on flat
tori $\R^n / L$ have $L^{\infty}$-norms bounded independently of the
eigenvalue. In the case of irrational flat tori, it follows that
$L^2$-normalized eigenfunctions have uniformly bounded $L^{\infty}$-norms.
Similar bases exist on other flat manifolds. Does this property characterize
flat manifolds? We give an affirmative answer for compact Riemannian manifolds
with completely integrable geodesic flows.

</DOC>
<DOC>
<DOCNO> 123000 </DOCNO>
Confusion of Diffuse Objects in the X-ray Sky


  Most of the baryons in the present-day universe are thought to reside in
intergalactic space at temperatures of 10^5-10^7 K. X-ray emission from these
baryons contributes a modest (~10%) fraction of the ~ 1 keV background whose
prominence within the large-scale cosmic web depends on the amount of
non-gravitational energy injected into intergalactic space by supernovae and
AGNs. Here we show that the virialized regions of groups and clusters cover
over a third of the sky, creating a source-confusion problem that may hinder
X-ray searches for individual intercluster filaments and contaminate
observations of distant groups.

</DOC>
<DOC>
<DOCNO> 11727 </DOCNO>
Meissner-London currents in superconductors with rectangular cross


  Exact analytic solutions are presented for the magnetic moment and screening
currents in the Meissner state of superconductor strips with rectangular cross
section in a perpendicular magnetic field and/or with transport current. The
extension to finite London penetration is achieved by an elegant numerical
method which works also for disks. The surface current in the specimen corners
diverges as l^(-1/3) where l is the distance from the corner. This enhancement
reduces the barrier for vortex penetration and should increase the nonlinear
Meissner effect in d-wave superconductors.

</DOC>
<DOC>
<DOCNO> 9204 </DOCNO>
Kinetic Theory of Collective Excitations and Damping in Bose-Einstein


  We calculate the frequencies and damping rates of the low-lying collective
modes of a Bose-Einstein condensed gas at nonzero temperature. We use a complex
nonlinear Schr\"odinger equation to determine the dynamics of the condensate
atoms, and couple it to a Boltzmann equation for the noncondensate atoms. In
this manner we take into account both collisions between
noncondensate-noncondensate and condensate-noncondensate atoms. We solve the
linear response of these equations, using a time-dependent gaussian trial
function for the condensate wave function and a truncated power expansion for
the deviation function of the thermal cloud. As a result, our calculation turns
out to be characterized by two dimensionless parameters proportional to the
noncondensate-noncondensate and condensate-noncondensate mean collision times.
We find in general quite good agreement with experiment, both for the
frequencies and damping of the collective modes.

</DOC>
<DOC>
<DOCNO> 170132 </DOCNO>
Spin measurement retrodiction revisited


  The retrodiction of spin measurements along a set of different axes is
revisited in detail. The problem is presented in two different pictures, a
geometric and a general algebraic one. Explicit measurement operators that
allow the retrodiction are given for the case of three and four axes. For the
Vaidman-Aharanov-Albert case of three orthogonal axes the quantum network is
constructed for two different initial Bell states.

</DOC>
<DOC>
<DOCNO> 10170 </DOCNO>
Bulk dynamics for interfacial growth models


  We study the influence of the bulk dynamics of a growing cluster of particles
on the properties of its interface. First, we define a {\it general bulk growth
model} by means of a continuum Master equation for the evolution of the bulk
density field. This general model just considers arbitrary addition of
particles (though it can be easily generalized to consider substraction) with
no other physical restriction. The corresponding Langevin equation for this
bulk density field is derived where the influence of the bulk dynamics is
explicitly shown. Finally, when it is assumed a well-defined interface for the
growing cluster, the Langevin equation for the height field of this interface
for some particular bulk dynamics is written. In particular, we obtain the
celebrated Kardar-Parisi-Zhang (KPZ) equation. A Monte Carlo simulation
illustrates the theoretical results.

</DOC>
<DOC>
<DOCNO> 123319 </DOCNO>
State-or-the-art Accretion and Wind Solutions Around Black Holes


  We report all possible basic solutions of an advective disk model and use
them to explain major observations from black hole candidates.

</DOC>
<DOC>
<DOCNO> 99756 </DOCNO>
Segre varieties and Lie symmetries


  Using the classical S.Lie method we obtain a complete description of
infinitesimal symmetries of a holomorphic PDE system defining the Segre family
of a real analytic hypersurface. This gives a new proof of some well known
results of CR geometry.

</DOC>
<DOC>
<DOCNO> 71427 </DOCNO>
QCD Radiation off Heavy Particles


  We study QCD radiation in decay processes involving heavy particles. As
input, the first-order gluon emission rate is calculated in a number of
reactions, and comparisons of the energy flow patterns show a non-negligible
process dependence. To proceed further, the QCD parton shower language offers a
convenient approach to include multi-gluon emission effects, and to describe
exclusive event properties. An existing shower algorithm is extended to take
into account the process-dependent mass, spin and parity effects, as given by
the matrix element calculations. This allows an improved description of
multiple gluon emission effects off b and t quarks, and also off nonstandard
particles like squarks and gluinos. Phenomenological applications are presented
for bottom production at LEP, Higgs particle decay to heavy flavours, top
production and decay at linear colliders, and some simple supersymmetric
processes.

</DOC>
<DOC>
<DOCNO> 12360 </DOCNO>
Condensate Fragmentation in a New Exactly Solvable Model for Confined


  Based on Richardson's exact solution of the pairing model and the Gaudin
model for spin systems we derive a new class of exactly solvable models for
finite boson system. As an example we solve a particular hamiltonian which
displays a transition to a fragmented condensate for repulsive pairing
interactions.

</DOC>
<DOC>
<DOCNO> 13081 </DOCNO>
Time resolved nanosecond vortex dynamics in high Tc superconducting


  We report on the observation of the rearrangement of vortices in the ns time
scale following a fast magnetic field variation due to selective local heating
of a high Tc superconducting film. Detailed simulations describing the measured
photoinduced voltage signals along the film lead to a better understanding of
vortex dynamics in fast regimes, where mean vortex velocities reach 10000 m/s

</DOC>
<DOC>
<DOCNO> 102428 </DOCNO>
The Hopf Rings for KO and KU


  We compute the mod two homology Hopf rings of the spectra KO and KU. The
spaces in these spectra are the infinite classical groups and their coset
spaces, and their homology was first calculated in the Cartan seminars, but the
Hopf ring structure was first determined in the second author's unpublished PhD
thesis. The presentation given here serves as an introduction to the first
author's much more intricate work on the connective spectrum bo. The Hopf ring
viewpoint turns out to be very convenient for understanding the homological
effect of various maps between classical groups and fibrations of their
connective covers.

</DOC>
<DOC>
<DOCNO> 9007 </DOCNO>
Coulomb repulsion versus Hubbard repulsion in a disordered chain


  We study the difference between on site Hubbard and long range Coulomb
repulsions for two interacting particles in a disordered chain. While Hubbard
repulsion can only yield weak critical chaos with intermediate spectral
statistics, Coulomb repulsion can drive the two particle system to quantum
chaos with Wigner-Dyson spectral statistics. For intermediate strengths U of
the two repulsions in one dimension, there is a crossover regime where
delocalization and spectral rigidity are maximum, whereas the limits of weak
and strong U are characterized by a stronger localization and uncorrelated
energy levels.

</DOC>
<DOC>
<DOCNO> 10169 </DOCNO>
Edge and bulk effects in the Terahertz-photoconductivity of an antidot


  We investigate the Terahertz(THz)-response of a square antidot superlattice
by means of photoconductivity measurements using a
Fourier-transform-spectrometer. We detect, spectrally resolved, the cyclotron
resonance and the fundamental magnetoplasmon mode of the periodic superlattice.
In the dissipative transport regime both resonances are observed in the
photoresponse. In the adiabatic transport regime, at integer filling factor
$\nu =2$, only the cyclotron resonance is observed. From this we infer that
different mechanisms contribute to converting the absorption of THz-radiation
into photoconductivity in the cyclotron and in the magnetoplasmon resonances,
respectively.

</DOC>
<DOC>
<DOCNO> 116286 </DOCNO>
A semi-classical over-barrier model for charge exchange between highly


  Absolute total cross sections for electron capture between slow, highly
charged ions and alkali targets have been recently measured. It is found that
these cross sections follow a scaling law with the projectile charge which is
different from the one previously proposed basing on a classical over-barrier
model (OBM) and verified using rare gases and molecules as targets. In this
paper we develop a "semi-classical" (i.e. including some quantal features) OBM
attempting to recover experimental results. The method is then applied to
ion-hydrogen collisions and compared with the result of a sophisticated
quantum-mechanical calculation. In the former case the accordance is very good,
while in the latter one no so satisfactory results are found. A qualitative
explanation for the discrepancies is attempted.

</DOC>
<DOC>
<DOCNO> 122649 </DOCNO>
Keck Diffraction-Limited Imaging of the Young Quadruple Star System HD


  This paper presents diffraction-limited 1-18 micron images of the young
quadruple star system HD 98800 obtained with the W. M. Keck 10-m telescopes
using speckle and adaptive optics imaging at near-IR wavelengths and direct
imaging at mid-IR wavelengths. The two components of the visual binary, A and
B, both themselves spectroscopic binaries, were separable at all wavelengths,
allowing us to determine their stellar and circumstellar properties. Combining
these observations with spectroscopic data from the literature, we derive an
age of 10 Myr, masses of 0.93 and 0.64 M_sun and an inclination angle of 58 deg
for the spectroscopic components of HD 98800 B, and an age of 10 Myr and a mass
of 1.1 M_sun for HD 98800 Aa. Our data confirm that the large mid-IR excess is
entirely associated with HD 98800 B. This excess exhibits a black body
temperature of 150 K and a strong 10 micron silicate emission feature. The
theoretical equilibrium radius of large, perfectly absorbing, 150 K grains
around HD 98800 B is 2.4 AU, suggesting a circum-spectroscopic binary
distribution. Our observations set important upper limits on the size of the
inner dust radius of ~2 AU (mid-IR data) and on the quantity of scattered light
of <10% (H-band data). For an inner radius of 2 AU, the dust distribution must
have a height of at least 1 AU to account for the fractional dust luminosity of
\~20% L_B. Based on the scattered light limit, the dust grains responsible for
the excess emission must have an albedo of <0.33. The presence of the prominent
silicate emission feature at 10 microns implies dust grain radii of >2 microns.
The total mass of the dust, located in a circumbinary disk around the HD 98800
B, is >0.002 M_earth. The orbital dynamics of the A-B pair are likely
responsible for the disk geometry.

</DOC>
<DOC>
<DOCNO> 69205 </DOCNO>
Moving Domain Walls in $AdS_5$ and Graceful Exit from Inflation


  We consider moving-brane-solutions in AdS type back ground. In the first
Randall-Sundrum configuration, there are two branes at fixed points of the
orbifold symmetry. We point out that if one brane is fixed and the other brane
is moving, the configuration is still a solution provided the moving brane has
a specific velocity determined by its tension and bulk cosmological constant.
In the absence of the $\bf Z_2$ symmetry, we can construct multi-brane
configurations by patching AdS-Schwarzshild solutions. In this case, we show
that the 4-dimensional effective cosmological constant on the brane world is
not well defined. We find a condition for a brane to be stationary. Using the
brane scattering, we suggest a scenario of inflation on the brane universe
during a finite time, i.e, a scenario of a graceful exit of inflation.

</DOC>
<DOC>
<DOCNO> 121543 </DOCNO>
Galactic Superwinds at Low and High Redshift


  In this contribution I summarize our current knowledge of the nature and
significance of starburst-driven galactic superwinds. These flows are driven
primarily by the kinetic energy supplied by supernovae. Superwinds are complex,
multiphase phenomena requiring a panchromatic observational approach. They are
ubiquitous in galaxies in which the global star-formation rate per unit area
exceeds roughly 10$^{-1}$ M$_{\odot}$ yr$^{-1}$ kpc$^{-2}$ (a condition
satisfied by local starbursts and high-z Lyman Break galaxies). Data on X-ray
emission, optical line-emission, and optical/UV interstellar absorption-lines
together imply that the mass outflow rates are comparable to the
star-formation-rates and that the conversion of kinetic energy from supernovae
to superwind is quite efficient ($\sim$ 30 to 100%). Measured/inferred outflow
speeds range from a few $\times 10^2$ to 10$^3$ km/s and appear to be
independent of the rotation speed of the ``host'' galaxy. The outflows are
dusty (dust/gas ratios of $\sim$ 1% by mass). These properties imply that
superwinds may have established the mass-metallicity relation in elliptical and
bulges, polluted the inter-galactic medium to a metallicity of $\sim$ 10 to 30%
solar, heated the inter-galactic medium by up to $\sim$1 kev per baryon, and
ejected enough dust into the inter-galactic medium to have potentially
observable consequences.

</DOC>
<DOC>
<DOCNO> 85268 </DOCNO>
The Formation of non-Keplerian Rings of Matter about Compact Stars


  The formation of energetic rings of matter in a Kerr spacetime with an
outward pointing acceleration field does not appear to have previously been
noted as a relativistic effect. In this paper we show that such rings are a
gravimagneto effect with no Newtonian analog, and that they do not occur in the
static limit. The energy efficiency of these rings can, depending of the
strength of the acceleration field, be much greater than that of Keplerian
disks. The rings rotate in a direction opposite to that of compact star about
which they form. The size and energy efficiency of the rings depend on the
fundamental parameters of the spacetime as well as the strength the
acceleration field.

</DOC>
<DOC>
<DOCNO> 69387 </DOCNO>
An Exposition on Inflationary Cosmology


  This paper is intended to offer a pedagogical treatment of cosmological
modeling and inflationary cosmology. In recent years, inflation has become
accepted as a standard scenario making predictions that are testable by
observations of the cosmic background. It is therefore manifest that anyone
wishing to pursue the study of cosmology and large-scale structure should have
this scenario at their disposal. The author hopes this paper will serve to
`bridge the gap' between technical and popular accounts of the subject.

</DOC>
<DOC>
<DOCNO> 12020 </DOCNO>
Very fast relaxation in polycarbonate glass


  Low-frequency Raman and inelastic neutron scattering of amorphous bis-phenol
A polycarbonate is measured at low temperature, and compared. The vibrational
density of states and light-vibration coupling coefficient are determined. The
frequency dependences of these parameters are explained by propagating
vibration modes up to an energy of about 1 meV, and fracton-like modes in more
cohesive domains at higher energies. The vibrational dynamics is in agreement
with a disorder in the glass, which is principally of bonding or of elasticity
instead of density.

</DOC>
<DOC>
<DOCNO> 70750 </DOCNO>
Hedgehogs in higher dimensional gravity with curvature self-interactions


  Static solutions of the higher dimensional Einstein-Hilbert gravity
supplemented by quadratic curvature self-interactions are discussed in the
presence of hedgehog configurations along the transverse dimensions. The
quadratic part of the action is parametrized in terms of the (ghost-free)
Euler-Gauss-Bonnet curvature invariant. Spherically symmetric profiles of the
transverse metric admit exponentially decaying warp factors both for positive
and negative bulk cosmological constants.

</DOC>
<DOC>
<DOCNO> 101202 </DOCNO>
Note on the Curvature and Index of Almost Unitary Contraction Operator


  In the recent preprint (OA/0006224) S. Parrott proved the equality between
the Arveson`s curvature and the Fredholm index of a "pure" contraction with
finite defect numbers. In the present note one derives a similar formula in the
"non-pure" case.

</DOC>
<DOC>
<DOCNO> 119554 </DOCNO>
Three Dimensional Radiative Transfer


  Radiative Transfer (RT) effects play a crucial role in the thermal history of
the intergalactic medium. Here I discuss recent advances in the development of
numerical methods that introduce RT to cosmological hydrodynamics. These
methods can also readily be applied to time dependent problems on interstellar
and galactic scales.

</DOC>
<DOC>
<DOCNO> 102617 </DOCNO>
A telescope comparison lemma for THH


  We extend to the non-connective case a lemma of Bokstedt about the
equivalence of the telescope with a more complicated homotopy colimit of
symmetric spectra used in the construction of THH.

</DOC>
<DOC>
<DOCNO> 152119 </DOCNO>
Hagedorn Behavior of Little String Theories


  We examine the Hagedorn behavior of little string theory using its
conjectured duality with near-horizon NS5-branes. In particular, by studying
the string-corrected NS5-brane supergravity solution, it is shown that
tree-level corrections to the temperature vanish, while the leading one-loop
string correction generates the correct temperature dependence of the entropy
near the Hagedorn temperature. Finally, the Hagedorn behavior of ODp-brane
theories, which are deformed versions of little string theory, is considered
via their supergravity duals.

</DOC>
<DOC>
<DOCNO> 40015 </DOCNO>
Instantons in Deep-Inelastic Scattering


  In view of the new (preliminary) search results for instanton-induced events
at HERA from the H1 collaboration, we present a brief discussion of
(controllable) theoretical uncertainties, both in the event topology and the
calculated rate.

</DOC>
<DOC>
<DOCNO> 40671 </DOCNO>
Four-Neutrino Scenarios


  The main features of four-neutrino 3+1 and 2+2 mixing schemes are reviewed,
after a discussion on the necessity of at least four massive neutrinos if the
solar, atmospheric and LSND anomalies are due to neutrino oscillations.
Complete list of references on four-neutrino mixing at
http://www.to.infn.it/~giunti/neutrino

</DOC>
<DOC>
<DOCNO> 71747 </DOCNO>
Noncommutative and Non-Anticommutative Quantum Field Theory


  A noncommutative and non-anticommutative quantum field theory is formulated
in a superspace, in which the superspace coordinates satisfy noncommutative and
non-anticommutative relations. A perturbative scalar field theory is
investigated in which only the non-anticommutative algebraic structure is kept,
and one loop diagrams are calculated and found to be finite due to the damping
caused by a Gaussian factor in the propagator.

</DOC>
<DOC>
<DOCNO> 117868 </DOCNO>
The Ulysses Supplement to the GRANAT/WATCH Catalog of Cosmic Gamma-Ray


  We present 3rd interplanetary network (IPN) localization data for 56
gamma-ray bursts in the GRANAT/ WATCH catalog which occurred between 1990
November and 1994 September. These localizations are obtained by triangulation
using various combinations of spacecraft in the IPN, which consisted of
Ulysses, BATSE, Pioneer Venus Orbiter (PVO), Mars Observer (MO), WATCH, and
PHEBUS. The intersections of the triangulation annuli with the WATCH error
circles produce error boxes with areas as small as 16 sq. arcmin., reducing the
sizes of the error circles by up to a factor of 800.

</DOC>
<DOC>
<DOCNO> 102290 </DOCNO>
Algebraic construction of Witten's top Chern class


  We give a construction of Witten's "top Chern class" on the compactified
moduli space of curves with higher spin structures and show that it satisfies
most of the axioms proposed in math.AG/9905034.

</DOC>
<DOC>
<DOCNO> 12450 </DOCNO>
Fast Approximation of Centrality


  Social studies researchers use graphs to model group activities in social
networks. An important property in this context is the centrality of a vertex:
the inverse of the average distance to each other vertex. We describe a
randomized approximation algorithm for centrality in weighted graphs. For
graphs exhibiting the small world phenomenon, our method estimates the
centrality of all vertices with high probability within a (1+epsilon) factor in
near-linear time.

</DOC>
<DOC>
<DOCNO> 122368 </DOCNO>
The Abundance and Emission of H2O and O2 in Clumpy Molecular Clouds


  Recent observations with the Submillimeter Wave Astronomy Satellite indicate
abundances of gaseous H2O and O2 in dense molecular clouds which are
significantly lower than found in standard homogeneous chemistry models. We
present here results for the thermal and chemical balance of inhomogeneous
molecular clouds exposed to ultraviolet radiation in which the abundances of
H2O and O2 are computed for various density distributions, radiation field
strengths and geometries. It is found that an inhomogeneous density
distribution lowers the column densities of H2O and O2 compared to the
homogeneous case by more than an order of magnitude at the same A_V. O2 is
particularly sensitive to the penetrating ultraviolet radiation, more so than
H2O. The S140 and rho Oph clouds are studied as relevant test cases of
star-forming and quiescent regions. The SWAS results of S140 can be
accommodated naturally in a clumpy model with mean density of 2x10^3 cm-3 and
enhancement I_UV=140 compared with the average interstellar radiation field, in
agreement with observations of [CI] and 13CO of this cloud. Additional
radiative transfer computations suggest that this diffuse H2O component is
warm, ~60-90 K, and can account for the bulk of the 1_10-1_01 line emission
observed by SWAS. The rho Oph model yields consistent O2 abundances but too
much H2O, even for [C]/[O]=0.94, if I_UV<10 respectively <40 for a mean density
of 10^3 respectively 10^4 cm-3. It is concluded that enhanced photodissociation
in clumpy regions can explain the low H2O and O2 abundances and emissivities
found in the large SWAS beam for extended molecular clouds, but that additional
freeze-out of oxygen onto grains is needed in dense cold cores.

</DOC>
<DOC>
<DOCNO> 169698 </DOCNO>
The thermodynamic cost of reliability and low temperatures: Tightening


  Landauer's principle states that the erasure of one bit of information
requires the free energy kT ln 2. We argue that the reliability of the bit
erasure process is bounded by the accuracy inherent in the statistical state of
the energy source (`the resources') driving the process. We develop a general
framework describing the `thermodynamic worth' of the resources with respect to
reliable bit erasure or good cooling. This worth turns out to be given by the
distinguishability of the resource's state from its equilibrium state in the
sense of a statistical inference problem. Accordingly, Kullback-Leibler
relative information is a decisive quantity for the `worth' of the resource's
state. Due to the asymmetry of relative information, the reliability of the
erasure process is bounded rather by the relative information of the
equilibrium state wit respect to the actual state than by the relative
information of the actual state with respect to the equilibrium state (which is
the free energy up to constants).

</DOC>
<DOC>
<DOCNO> 101998 </DOCNO>
Chains of Frobenius subalgebras of so(M) and the corresponding twists


  Chains of extended jordanian twists are studied for the universal enveloping
algebras U(so(M)). The carrier subalgebra of a canonical chain F cannot cover
the maximal nilpotent subalgebra N(so(M)). We demonstrate that there exist
other types of Frobenius subalgebras in so(M) that can be large enough to
include N(so(M)). The problem is that the canonical chains F do not preserve
the primitivity on these new carrier spaces. We show that this difficulty can
be overcome and the primitivity can be restored if one changes the basis and
passes to the deformed carrier spaces. Finally the twisting elements for the
new Frobenius subalgebras are explicitly constructed. This gives rise to a new
family of universal R-matrices for orthogonal algebras. For a special case of g
= so(5) and its defining representation we present the corresponding matrix
solution of the Yang-Baxter equation.

</DOC>
<DOC>
<DOCNO> 150852 </DOCNO>
Non-Perturbative Mass Renormalization in Quenched QED from the Worldline


  Following Feynman's successful treatment of the polaron problem we apply the
same variational principle to quenched QED in the worldline formulation. New
features arise from the description of fermions by Grassmann trajectories, the
supersymmetry between bosonic and fermionic variables and the much more
singular structure of a renormalizable gauge theory like QED in 3+1 dimensions.
We take as trial action a general retarded quadratic action both for the
bosonic and fermionic degrees of freedom and derive the variational equations
for the corresponding retardation functions. We find a simple analytic,
non-perturbative, solution for the anomalous mass dimension gamma_m(alpha) in
the MS scheme. For small couplings we compare our result with recent four-loop
perturbative calculations while at large couplings we find that gamma_m(alpha)
becomes proportional to (alpha)^(1/2). The anomalous mass dimension shows no
obvious sign of the chiral symmetry breaking observed in calculations based on
the use of Dyson-Schwinger equations, however we find that a perturbative
expansion of gamma_m(alpha) diverges for alpha > 0.7934. Finally, we
investigate the behaviour of gamma_m(alpha) at large orders in perturbation
theory.

</DOC>
<DOC>
<DOCNO> 170163 </DOCNO>
A Refutation of Bell's Theorem


  Bell's Theorem was developed on the basis of considerations involving a
linear combination of spin correlation functions, each of which has a distinct
pair of arguments. The simultaneous presence of these different pairs of
arguments in the same equation can be understood in two radically different
ways: either as `strongly objective,' that is, all correlation functions
pertain to the same set of particle pairs, or as `weakly objective,' that is,
each correlation function pertains to a different set of particle pairs.
  It is demonstrated that once this meaning is determined, no discrepancy
appears between local realistic theories and quantum mechanics: the discrepancy
in Bell's Theorem is due only to a meaningless comparison between a local
realistic inequality written within the strongly objective interpretation (thus
relevant to a single set of particle pairs) and a quantum mechanical prediction
derived from a weakly objective interpretation (thus relevant to several
different sets of particle pairs).

</DOC>
<DOC>
<DOCNO> 67740 </DOCNO>
Evolution of twist-three parton distributions in QCD beyond the large


  We formulate a consistent 1/N_c^2 expansion of the QCD evolution equations
for the twist-three quark distributions g_2(x,Q^2), h_L(x,Q^2) and e(x,Q^2)
based on the interpretation of the evolution as a three-particle
quantum-mechanical problem with hermitian Hamiltonian. Each distribution
amplitude can be decomposed in contributions of partonic components with
DGLAP-type scale dependence. We calculate the 1/N_c^2 corrections to the
evolution of the dominant component with the lowest anomalous dimension - the
only one that survives in the large-N_c limit - and observe a good agreement
with the exact numerical results for N_c=3. The 1/N_c^2 admixture of operators
with higher anomalous dimensions is shown to be concentrated at a few lowest
partonic components and in general is rather weak.

</DOC>
<DOC>
<DOCNO> 68324 </DOCNO>
Loop Corrections to the Neutral Higgs Boson Sector of the MSSM with


  We compute one-loop corrections to the mass matrix of the neutral Higgs
bosons of the Minimal Supersymmetric Standard Model with explicit CP violation.
We use the effective potential method, allowing for arbitrary splitting between
squark masses. We include terms O(g^2 h^2), where g and h stand for electroweak
gauge and Yukawa couplings, respectively. Leading two-loop corrections are
taken into account by means of appropriately defined running quark masses.

</DOC>
<DOC>
<DOCNO> 152605 </DOCNO>
Non-Semisimple Gaugings of D=5 N=8 Supergravity


  The recent construction of the non-semisimple gaugings of maximal D=5
supergravity is reported here. This construction is worked out in the so-called
rheonomic approach, based on Free Differential Algebras and the solution of
their Bianchi identities. In this approach the dualization mechanism between
one-forms and two-forms is more transparent. The lagrangian is unnecessary
since the field equations follow from closure of the supersymmetry algebra.
These theories contain 12-r self-dual two-forms and 15+r gauge vectors, r of
which are abelian and neutral. Such theories, whose existence has been proved
and their supersymmetry algebra constructed, have potentially interesting
properties in relation with domain wall solutions and the trapping of gravity.

</DOC>
<DOC>
<DOCNO> 71763 </DOCNO>
Factorization vs. Flavor SU(3) in Charmless B Decays


  Two types of predictions for charmless B decays are compared. One involves
estimates based on factorization and models for form factors, while the other
involves the use of flavor SU(3), sometimes with assumptions about the
smallness of certain amplitudes. After a comparison of some factorization
predictions with recent data, specific decays of $B$ mesons to two charmless
mesons are discussed.

</DOC>
<DOC>
<DOCNO> 120617 </DOCNO>
Generic Spectrum and Ionization Efficiency of a Heavy Initial Mass


  We calculate the generic spectral signature of an early population of massive
stars at high redshifts. For metal-free stars in the mass range of 100-1000
solar masses, we find that the combined spectral luminosity per unit stellar
mass is almost independent of the mass distribution of these stars. To zeroth
order, the generic spectrum resembles a black-body with an effective
temperature of ~10^5 K, making these stars highly efficient at ionizing
hydrogen and helium. The production rate of ionizing radiation per stellar mass
by stars more massive than 100 solar masses is larger by about an order of
magnitude for hydrogen and He I, and by about two orders of magnitude for He
II, than the emission from a standard initial mass function. This would result
in unusually strong hydrogen and helium recombination lines from the
surrounding interstellar medium. It could also alleviate the current difficulty
of ionizing the intergalactic medium at z>6 with the cosmic star formation rate
inferred at somewhat lower redshifts.

</DOC>
<DOC>
<DOCNO> 120985 </DOCNO>
Comparison of the Two Followup Observation Strategies for Gravitational


  There are two different strategies of followup observations for the detection
of planets by using microlensing. One is detecting the light curve anomalies
affected by the planetary caustic from continuous monitoring of all events
detected by microlensing survey programs (type I strategy) and the other is
detecting anomalies near the peak amplification affected by the central caustic
from intensive monitoring of high amplification events (type II strategy). It
was shown by Griest & Safizadeh that the type II strategy yields high planet
detection efficiency per event. However, it is not known the planet detection
rate by this strategy can make up a substantial fraction of the total rate. In
this paper, we estimate the relative planet detection rates expected under the
two followup observation strategies. From this estimation, we find that the
rate under the type II strategy is substantial and will comprise $\sim 1/4$ --
1/2 of the total rate. We also find that compared to the type I strategy the
type II strategy is more efficient in detecting planets located outside of the
lensing zone. We determine the optimal monitoring frequency of the type II
strategy to be $\sim 20$ times/night, which can be easily achieved by the
current microlensing followup programs even with a single telescope.

</DOC>
<DOC>
<DOCNO> 120197 </DOCNO>
A Survey for Faint Stars of Large Proper Motion Using Extra Poss II


  We have conducted a search for new stars of high proper motion ($\geq$0.4
arcsec yr$^{-1}$) using POSS II fields for which an extra IIIaF (red) plate of
good quality exists, along with useable IIIaJ (blue) and IV-N (infrared) plates
taken at epochs differing by a minimum of 1.5 years. Thirty-five fields at
Galactic latitudes $|b| \geq$ 20$^o$ were measured, covering some 1378 deg$^2$,
or 3.3% of the sky. Searches with three plate combinations as well as all four
plates were also made. Seven new stars were found with $\mu \geq$0.5 arcsec
yr$^{-1}$, which were therefore missed in the Luyten Half Second (LHS) Catalog.
One of these is a common proper motion binary consisting of two subdwarf M
stars; another is a cool white dwarf with probable halo kinematics. As a test
of our completeness -- and of our ability to test that of Luyten -- 216 of 230
catalogued high proper motion stars were recovered by the software, or 94%.
Reasons for incompleteness of the LHS are discussed, such as the simple fact
that POSS II plates have deeper limiting magnitudes and greater overlap than
did POSS I. Nonetheless, our results suggest that the LHS is closer to 90%
complete than recent estimates in the literature (e.g 60%), and we propose a
reason to account for one such lower estimate. The conclusion that the LHS
Catalog is more complete has implications for the nature of the halo dark
matter. In particular it strengthens the constraint on the local density of
halo stars, especially white dwarfs at M$_V\sim$17-18.

</DOC>
<DOC>
<DOCNO> 72298 </DOCNO>
Noncommutativity in Space and Primordial Magnetic Field


  In this paper we show that noncommutativity in spatial coordinates can
generate magnetic field in the early Universe on a horizon scale. The strength
of such a magnetic field depends on the number density of massive charged
particles present at a given moment. This allows us to trace back the
temperature dependence of the noncommutativity scale from the bounds on
primordial magnetic field coming from nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 118784 </DOCNO>
The Central Gas Systems of Early-Type Galaxies Traced by Dust Feature:


  We investigated the central gas systems of E/S0 galaxies by making use of the
WFPC2 images of the Hubble Space Telescope archive. We searched the gas systems
that were traced by the dust with a new method of making color excess images in
F555W - F814W (V-I). Out of 25 sample galaxies, we detected gas system in 14
galaxies. The dust was newly detected in two galaxies that were thought to
contain no dust based on single band, pre-refurbishment data. The full extents
of the gas systems are 0.1 to 3.5 kpc, and the masses of the gas, log M(gas)
[M(solar)], are 4.2 to 7.2. The AGN activity is well correlated with existence
of the gas systems. None of galaxies without the gas systems show the AGN
activity. On the other hand, some galaxies with the gas systems show the AGN
activity; optical AGN activities are shown in 5 out of 11 galaxies of which
AGNs are optically studied, and radio activities are shown in 6 out of 14
galaxies. This shows that the AGN activity is driven with the gas system.

</DOC>
<DOC>
<DOCNO> 71805 </DOCNO>
Looking for Instanton-induced Processes at HERA Using a Multivariate


  We present a method to discriminate instanton-induced processes from standard
DIS background based on Range Searching. This method offers fast and automatic
scanning of a large number of variables for a combination of variables giving
high signal to background ratio and the smallest theoretical and experimental
uncertainties.

</DOC>
<DOC>
<DOCNO> 121913 </DOCNO>
VLT identification of the optical afterglow of the gamma-ray burst GRB


  We report the discovery of the gamma-ray burst GRB 000131 and its optical
afterglow. The optical identification was made with the VLT 84 hours after the
burst following a BATSE detection and an Inter Planetary Network localization.
GRB 000131 was a bright, long-duration GRB, with an apparent precursor signal
62 s prior to trigger. The afterglow was detected in ESO VLT, NTT, and DK1.54m
follow-up observations. Broad-band and spectroscopic observations of the
spectral energy distribution reveals a sharp break at optical wavelengths which
is interpreted as a Ly-alpha absorption edge at 6700 A. This places GRB 000131
at a redshift of 4.500 +/- 0.015. The inferred isotropic energy release in
gamma rays alone was approximately 10^54 erg (depending on the assumed
cosmology). The rapid power-law decay of the afterglow (index alpha=2.25,
similar to bursts with a prior break in the lightcurve), however, indicates
collimated outflow, which relaxes the energy requirements by a factor of < 200.
The afterglow of GRB 000131 is the first to be identified with an 8-m class
telescope.

</DOC>
<DOC>
<DOCNO> 40571 </DOCNO>
Measurement of B0d - B0d-bar mixing rate from the time evolution of


  We report a determination of the B0d - B0d-bar mixing parameter Delta-m_d
based on the time evolution of dilepton yields in Upsilon(4S) decays. The
measurement is based on a 5.9 /fb data sample collected by the Belle detector
at KEKB. The proper-time difference distributions for same-sign and
opposite-sign dilepton events are simultaneously fitted to an expression
containing Delta-m_d as a free parameter. Using both muons and electrons, we
obtain Delta-m_d = 0.463 +- 0.008(stat.) +- 0.016(sys.) ps^{-1} This is the
first determination of Delta-m_d from time evolution measurements at the
Upsilon(4S). We also place limits on possible CPT violations.

</DOC>
<DOC>
<DOCNO> 11961 </DOCNO>
Looking Forward to Pricing Options from Binomial Trees


  We reconsider the valuation of barrier options by means of binomial trees
from a "forward looking" prospective rather than the more conventional
"backward induction" one used by standard approaches. This reformulation allows
us to write closed-form expressions for the value of European and American put
barrier-options on a non-dividend-paying stock.

</DOC>
<DOC>
<DOCNO> 121834 </DOCNO>
The AMS-01 Aerogel Threshold Cherenkov counter


  The Alpha Magnetic Spectrometer in a precursor version (AMS-01), was flown in
June 1998 on a 51.6 degrees orbit and at altitudes ranging between 320 and 390
km, on board of the space shuttle Discovery (flight STS-91). AMS-01 included an
Aerogel Threshold Cherenkov counter (ATC) to separate antiprotons from
electrons and positrons from protons, for momenta below 3.5 GeV/c. This paper
presents a description of the ATC counter and reports on its performances
during the flight STS-91.

</DOC>
<DOC>
<DOCNO> 100856 </DOCNO>
The Gromov-Witten invariants of symplectic manifolds


  We study the fix point components of the big torus action on the moduli space
of stable maps into a smooth projective toric variety, and apply Graber and
Pandharipande's localization formula for the virtual fundamental class to
obtain an explicit formula for the Gromov-Witten invariants of toric varieties.
Using this formula we compute all genus-0 3-point invariants of the Fano
manifold $\P(\O_{\P^2}(2) \oplus 1)$, and we show for the (non-Fano) manifold
$\P(\O_{\P^2}(3) \oplus 1)$ that its quantum cohomology ring does not
correspond to Batyrev's ring defined in \cite{bat93}.

</DOC>
<DOC>
<DOCNO> 102802 </DOCNO>
Universal Teichmuller Space


  We present an outline of the theory of universal Teichmuller space, viewed as
part of the theory of QS, the space of quasisymmetric homeomorphisms of a
circle. Although elements of QS act in one dimension, most results depend on a
two-dimensional proof. QS has a manifold structure modelled on a Banach space,
and after factorization by PSL(2,R} it becomes a complex manifold. This
quotient space contains deformation spaces of many types of dynamical system
and for every hyperbolic Riemann surface, and in this naive sense it is
universal. Here however, we focus on the analytic foundations of the theory
necessary for applications to dynamical systems and rigidity. We divide the
paper into two parts. The first part concerns the real theory of QS and results
that can be stated purely in real terms; the basic properties are given mostly
without proof, except in certain cases when an easy real-variable proof is
available. The second part of the paper brings in the complex analysis and
promotes the view that properties of quasisymmetric maps are most easily
understood by consideration of their possible two-dimensional quasiconformal
extensions.

</DOC>
<DOC>
<DOCNO> 122074 </DOCNO>
Modelling Self-Interacting CDM Haloes with a Cosmological Boltzmann Code


  We investigate the density profiles and evolution of weakly self-interacting
cold dark matter haloes using a numerical code based on the collisional
Boltzmann equation. This approach is alternative to N-body techniques in
following the dynamical evolution of haloes in the cosmological context and
taking into account particle self-interaction. The physical case with a cross
section inversely proportional to the relative velocity of the colliding
particles is modelled with an unprecedented resolution, spanning five orders of
magnitude on the radius for each halo. The modelled haloes cover a mass range
from dwarf galaxies to galaxy clusters. We find that for \sigma v_{100} \approx
10^{-24} cm^2/GeV, where \sigma is the cross section per unit mass and v_{100}
is the collision velocity in units of 100 km/s, soft cores in good agreement
with observations on galactic as well as on galaxy cluster scales are obtained.
Remarkably, the observed nearly invariance of the halo central density with
mass is reproduced.

</DOC>
<DOC>
<DOCNO> 67869 </DOCNO>
Overview of Chiral Perturbation Theory


  I present a quick overview of the current status of Chiral perturbation
theory in the meson sector. To illustrate the successes and some problems in
the description of the phenomenology, I focus on a few selected examples that
are relevant for DAFNE.

</DOC>
<DOC>
<DOCNO> 69818 </DOCNO>
NLO Monte-Carlo approach in 1 or 2 jets Photoproduction


  We present a method for calculating the photoproduction of jets at HERA based
on Next to Leading Logarithm QCD calculations. It is implemented in a
Monte-Carlo generator which allows us to easily compute any infra-red safe
cross sections for 1 or 2 jet observables using various jet reconstruction
algorithms. We focus on the possibility of extracting the gluon contents of the
photon and of the proton from present and future H1 and ZEUS data.

</DOC>
<DOC>
<DOCNO> 102163 </DOCNO>
On positivity of the Kadison constant and noncommutative Bloch theory


  In an earlier paper, we established a natural connection between the
Baum-Connes conjecture and noncommutative Bloch theory, viz. the spectral
theory of projectively periodic elliptic operators on covering spaces. We
elaborate on this connection here and provide significant evidence for a
fundamental conjecture in noncommutative Bloch theory on the non-existence of
Cantor set type spectrum. This is accomplished by establishing an explicit
lower bound for the Kadison constant of twisted group C*-algebras in a large
number of cases, whenever the multiplier is rational.

</DOC>
<DOC>
<DOCNO> 121494 </DOCNO>
Viscosity Mechanisms in Accretion Disks


  The self-sustained turbulence which develops in magnetized accretion disks is
suppressed in the weakly-ionized, quiescent disks of close binary stars.
Because accretion still proceeds during quiescence, another viscosity mechanism
operates in these systems. An anticorrelation of the recurrence times of SU UMa
dwarf novae with their mass ratio supports spiral waves or shock-waves tidally
induced by the companion star as the main process responsible for accretion in
the quiescent disks. Other weakly-ionized gaseous disks in systems lacking a
massive companion have to rely on yet another transport mechanism or they could
be essentially passive.

</DOC>
<DOC>
<DOCNO> 84818 </DOCNO>
Null limits of generalised Bonnor-Swaminarayan solutions


  The Bonnor-Swaminarayan solutions are boost-rotation symmetric space-times
which describe the motion of pairs of accelerating particles which are possibly
connected to strings (struts). In an explicit and unified form we present a
generalised class of such solutions with a few new observations. We then
investigate the possible limits in which the accelerations become unbounded.
The resulting space-times represent spherical impulsive gravitational waves
with snapping or expanding cosmic strings. We also obtain an exact solution for
a snapping string of finite length.

</DOC>
<DOC>
<DOCNO> 80617 </DOCNO>
P-vortices, nexuses and effects of gauge copies


  We perform the careful study of the gauge copies problem for the direct
center projection in SU(2) lattice gauge theory. Our results indicate that this
gauge is not appropriate for the investigation of the center vortices. We also
show that the point-like objects, nexuses, are important for the confinement
dynamics.

</DOC>
<DOC>
<DOCNO> 122124 </DOCNO>
A Theoretical Model for the $M_{\rm bh}-\sigma$ Relation for


  We construct a model for the formation of black holes within galactic bulges.
The initial state is a slowly rotating isothermal sphere, characterized by
effective transport speed $\aeff$ and rotation rate $\Omega$. The black hole
mass is determined when the centrifugal radius of the collapse flow exceeds the
capture radius of the central black hole. This model reproduces the observed
correlation between black hole masses and galactic velocity dispersions, $\mbh
\approx 10^8 M_\odot (\sigma/200 \kms)^4$, where $\sigma = \sqrt{2} \aeff$.
This model also predicts the ratio $\mrat$ of black hole mass to host mass:
$\mrat$ $\approx$ 0.004 $(\sigma/200 \kms)$.

</DOC>
<DOC>
<DOCNO> 152033 </DOCNO>
Notes on the Quantization of the Complex Linear Superfield


  The quantization of the complex linear superfield requires an infinite tower
of ghosts. Using the Batalin-Vilkovisky technique, Grisaru, Van Proeyen, and
Zanon have been able to define a correct procedure to construct a gauge-fixed
action. We generalize their technique by introducing the Lagrange multipliers
into the non-minimal sector and we study the characteristic BRST cohomology. We
show how the physical subspace is singled out. Finally, we quantize the model
in the presence of a background and of a quantum gauge superfield.

</DOC>
<DOC>
<DOCNO> 101785 </DOCNO>
Discrete Nodal Domain Theorems


  We give a detailed proof for two discrete analogues of Courant's Nodal Domain
Theorem.

</DOC>
<DOC>
<DOCNO> 83229 </DOCNO>
Ranking suspected answers to natural language questions using predictive


  In this paper, we describe a system to rank suspected answers to natural
language questions. We process both corpus and query using a new technique,
predictive annotation, which augments phrases in texts with labels anticipating
their being targets of certain kinds of questions. Given a natural language
question, an IR system returns a set of matching passages, which are then
analyzed and ranked according to various criteria described in this paper. We
provide an evaluation of the techniques based on results from the TREC Q&A
evaluation in which our system participated.

</DOC>
<DOC>
<DOCNO> 68826 </DOCNO>
A Note on Brane Inflation


  We demonstrate that there exists an inflationary solution on the positive
tension brane in the Randall-Sundrum scenario. Inflation is driven by a
slow-rolling scalar field on the brane and is achieved within the perturbative
limit of the radion field. We find that inflation on the positive tension brane
results in a slight increase in the separation between the two branes. However,
we show that the slow-roll inflation is not possible on the negative tension
brane.

</DOC>
<DOC>
<DOCNO> 120504 </DOCNO>
Radial velocity measurements of white dwarfs


  We present 594 radial velocity measurements for 71 white dwarfs obtained
during our search for binary white dwarfs and not reported elsewhere. We
identify three excellent candidate binaries, which require further observations
to confirm our preliminary estimates for their orbital periods, and one other
good candidate. We investigate whether our data support the existence of a
population of single, low mass (<~0.5 solar masses) white dwarfs (LMWDs). These
stars are difficult to explain in standard models of stellar evolution. We find
that a model with a mixed single/binary population is at least ~20 times more
likely to explain our data than a pure binary population. This result depends
on assumed period distributions for binary LMWDs, assumed companion masses and
several other factors. Therefore, the evidence in favour of the existence of a
population of single LMWDs is not sufficient, in our opinion, to firmly
establish the existence of such a population, but does suggest that extended
observations of LMWDs to obtain a more convincing result would be worthwhile .

</DOC>
<DOC>
<DOCNO> 13116 </DOCNO>
Comment on "Efficient, multiple-range random walk algorithm to calculate


  Comment an the recent Letter [Phys. Rev. Lett. 86, 2050 (2001)] by F.Wang and
D. P. Landau.

</DOC>
<DOC>
<DOCNO> 101365 </DOCNO>
A Theorem of Sanderson on Link Bordisms in Dimension 4


  The groups of link bordism can be identified with homotopy groups via the
Pontryagin-Thom construction. B.J. Sanderson computed the bordism group of 3
component surface-links using the Hilton-Milnor Theorem, and later gave a
geometric interpretation of the groups in terms of intersections of Seifert
hypersurfaces and their framings. In this paper, we geometrically represent
every element of the bordism group uniquely by a certain standard form of a
surface-link, a generalization of a Hopf link. The standard forms give rise to
an inverse of Sanderson's geometrically defined invariant.

</DOC>
<DOC>
<DOCNO> 68988 </DOCNO>
Models with Inverse Sfermion Mass Hierarchy and Decoupling of the SUSY


  We study the decoupling of the first two squark and slepton families in order
to lower the flavour changing neutral current effects. Models with inverse
sfermion mass hierarchy based upon gauged U(1) flavour symmetries provide a
natural framework where decoupling can be implemented. Decoupling requires a
large gap between the Fermi scale and the supersymmetry breaking scale.
Maintaining the electroweak symmetry breaking at the Fermi scale requires some
fine-tuning that we investigate by solving the two-loop renormalization group
equations. We show that the two-loop effects are governed by the anomaly
compensated by the Green-Schwarz mechanism and can be determined from the quark
and lepton masses. The electroweak breaking constraints lead to a small $\mu$
scenario where the LSP is Higgsino-like.

</DOC>
<DOC>
<DOCNO> 12039 </DOCNO>
Negatively Charged Excitons and Photoluminescence in Asymmetric Quantum


  We study photoluminescence (PL) of charged excitons ($X^-$) in narrow
asymmetric quantum wells in high magnetic fields B. The binding of all $X^-$
states strongly depends on the separation $\delta$ of electron and hole layers.
The most sensitive is the ``bright'' singlet, whose binding energy decreases
quickly with increasing $\delta$ even at relatively small B. As a result, the
value of B at which the singlet--triplet crossing occurs in the $X^-$ spectrum
also depends on $\delta$ and decreases from 35 T in a symmetric 10 nm GaAs well
to 16 T for $\delta=0.5$ nm. Since the critical values of $\delta$ at which
different $X^-$ states unbind are surprisingly small compared to the well
width, the observation of strongly bound $X^-$ states in an experimental PL
spectrum implies virtually no layer displacement in the sample. This casts
doubt on the interpretation of PL spectra of heterojunctions in terms of $X^-$
recombination.

</DOC>
<DOC>
<DOCNO> 117873 </DOCNO>
On dust-correlated Galactic emission in the Tenerife data


  Recently correlation analyses between Galactic dust emission templates and a
number of CMB data sets have led to differing claims on the origin of the
Galactic contamination at low frequencies. de Oliviera-Costa {\em et al} (1999)
have presented work based on Tenerife data supporting the spinning dust
hypothesis. Since the frequency coverage of these data is ideal to discriminate
spectrally between spinning dust and free-free emission, we used the latest
version of the Tenerife data, which have lower systematic uncertainty, to study
the correlation in more detail. We found however that the evidence in favor of
spinning dust originates from a small region at low Galactic latitude where the
significance of the correlation itself is low and is compromised by systematic
effects in the Galactic plane signal. The rest of the region was found to be
uncorrelated. Regions that correlate with higher significance tend to have a
steeper spectrum, as is expected for free-free emission. Averaging over all
correlated regions yields dust-correlation coefficients of $180\pm47$ and
$123\pm16$ $\mu$K /MJy sr$^{-1}$ at 10 and 15 GHz respectively.
  These numbers however have large systematic uncertainties that we have
identified and care should be taken when comparing with results from other
experiments. We do find evidence for synchrotron emission with spectral index
steepening from radio to microwave frequencies, but we cannot make conclusive
claims about the origin of the dust-correlated component based on the spectral
index estimates. Data with higher sensitivity are required to decide about the
significance of the dust-correlation at high Galactic latitudes and other
Galactic templates, in particular H$_\alpha$ maps, will be necessary for
constraining its origin.

</DOC>
<DOC>
<DOCNO> 71536 </DOCNO>
Dilaton Tadpoles, Warped Geometries and Large Extra Dimensions for


  We analyze the backreaction of dilaton tadpoles on the geometry of
non-supersymmetric strings. After finding explicit warped solutions for a
T-dual version of the Sugimoto model, we examine the possibility of realizing
large extra dimension scenarios within the context of non-supersymmetric string
models. Our analysis reveals an appealing mechanism to dynamically reduce the
number of flat, non-compact directions in non-supersymmetric string theories.

</DOC>
<DOC>
<DOCNO> 120497 </DOCNO>
Black Hole Mass Estimates from Reverberation Mapping and from Spatially


  Black hole (BH) masses that have been measured by reverberation mapping in
active galaxies fall significantly below the correlation between bulge
luminosity and BH mass determined from spatially resolved kinematics of nearby
normal galaxies. This discrepancy has created concern that one or both
techniques suffer from systematic errors. We show that BH masses from
reverberation mapping are consistent with the recently discovered relationship
between BH mass and galaxy velocity dispersion. Therefore the bulge
luminosities are the probable source of the disagreement, not problems with
either method of mass measurement. This result underscores the utility of the
BH mass -- velocity dispersion relationship. Reverberation mapping can now be
applied with increased confidence to galaxies whose active nuclei are too
bright or whose distances are too large for BH searches based on spatially
resolved kinematics.

</DOC>
<DOC>
<DOCNO> 116919 </DOCNO>
The RTA Betatron-Node Experiment: Limiting Cumulative BBU Growth In A


  The successful operation of a Two-Beam accelerator based on extended
relativistic klystrons hinges upon decreasing the cumulative dipole BBU growth
from an exponential to a more manageable linear growth rate. We describe the
theoretical scheme to achieve this, and a new experiment to test this concept.
The experiment utilizes a 1-MeV, 600-Amp, 200-ns electron beam and a short
beamline of periodically-spaced rf dipole-mode pillbox cavities and solenoid
magnets for transport. Descriptions of the beamline are presented, followed by
theoretical studies of the beam transport and dipole-mode growth.

</DOC>
<DOC>
<DOCNO> 118312 </DOCNO>
Large-Scale Sunyaev-Zel'dovich Effect: Measuring Statistical Properties


  We study the prospects for extracting detailed statistical properties of the
Sunyaev-Zel'dovich (SZ) effect associated with large scale structure using
upcoming multifrequency CMB experiments. The greatest obstacle to detecting the
large-angle signal is the confusion noise provided by the primary anisotropies
themselves, and to a lesser degree galactic and extragalactic foregrounds. We
employ multifrequency subtraction techniques and the latest foregrounds models
to determine the detection threshold for the Boomerang, MAP (several microK)
and Planck CMB (sub microK) experiments. Calibrating a simplified biased-tracer
model of the gas pressure off recent hydrodynamic simulations, we estimate the
SZ power spectrum, skewness and bispectrum through analytic scalings and N-body
simulations of the dark matter. We show that the Planck satellite should be
able to measure the SZ effect with sufficient precision to determine its power
spectrum and higher order correlations, e.g. the skewness and bispectrum.
Planck should also be able to detect the cross correlation between the SZ and
gravitational lensing effect in the CMB. Detection of these effects will help
determine the properties of the as yet undetected gas, including the manner in
which the gas pressure traces the dark matter.

</DOC>
<DOC>
<DOCNO> 121515 </DOCNO>
Molecular cloud complexes in detail: Interferometric observations of


  We have accumulated 12CO(1-0) and (2-1) data of several GMCs in M31 using the
Plateau de Bure Interferometer. The sample covers a range of 5 to 18 kpc
galactocentric distance and various physical conditions. The spatial resolution
attains values down to 3 pc. All GMCs investigated have been resolved into
several components, also seemingly quiescent clouds and not only the cases
where already the survey positions show obvious multiple-peaked spectra. Such
kinematically disjunct emission is however spatially coincident in the small
volume of the interferometer beam in M31, which strongly favours local effects
as the cause of the velocity splitting. This is well consistent with the
observed absence of strong streaming motions in the survey data. The nature of
the sometimes strong separation in velocity space needs further investigation.
The complete data set (i.e. including the large-scale survey) yields a uniquely
complete view of the molecular gas which allows to investigate the conditions
for star formation in detail and helps to establish guide lines for the
derivation of the properties of molecular gas.

</DOC>
<DOC>
<DOCNO> 101895 </DOCNO>
Sigma Models, Minimal Surfaces and Some Ricci Flat Pseudo Riemannian


  We consider the sigma models where the base metric is proportional to the
metric of the configuration space. We show that the corresponding sigma model
equation admits a Lax pair. We also show that this type of sigma models in two
dimensions are intimately related to the minimal surfaces in a flat pseudo
Riemannian 3-space. We define two dimensional surfaces conformally related to
the minimal surfaces in flat three dimensional geometries which enable us to
give a construction of the metrics of some even dimensional Ricci flat pseudo
Riemannian geometries.

</DOC>
<DOC>
<DOCNO> 85195 </DOCNO>
Classical Scalar Fields and the Generalized Second Law


  It has been shown that classical non-minimally coupled scalar fields can
violate all of the standard energy conditions in general relativity. Violations
of the null and averaged null energy conditions obtainable with such fields
have been suggested as possible exotic matter candidates required for the
maintenance of traversable wormholes. In this paper, we explore the possibility
that if such fields exist, they might be used to produce large negative energy
fluxes and macroscopic violations of the generalized second law (GSL) of
thermodynamics. We find that it appears to be very easy to produce large
magnitude negative energy fluxes in flat spacetime. However we also find,
somewhat surprisingly, that these same types of fluxes injected into a black
hole do {\it not} produce violations of the GSL. This is true even in cases
where the flux results in a decrease in the area of the horizon. We demonstrate
that two effects are responsible for the rescue of the GSL: the acausal
behavior of the horizon and the modification of the usual black hole entropy
formula by an additional term which depends on the scalar field.

</DOC>
<DOC>
<DOCNO> 122111 </DOCNO>
Radio Continuum and Recombination Line Study of UC HII Regions with


  We have carried out 21 cm radio continuum observations of 16 UC HII regions
using the VLA (D-array) in search of associated extended emission. We have also
observed H76$_\alpha$ recombination line towards all the sources and
He76$_\alpha$ line at the positions with strong H76$_\alpha$ line emission. The
UC HII regions have simple morphologies and large (>10) ratios of single-dish
to VLA fluxes. Extended emission was detected towards all the sources. The
extended emission consists of one to several compact components and a diffuse
extended envelope. All the UC HII regions but two are located in the compact
components, where the UC HII regions always correspond to their peaks. The
compact components with UC HII regions are usually smaller and denser than
those without UC HII regions. Our recombination line observations indicate that
the ultracompact, compact, and extended components are physically associated.
The UC HII regions and their associated compact components are likely to be
ionized by the same sources on the basis of the morphological relations
mentioned above. This suggests that almost all of the observed UC HII regions
are not `real' UC HII regions and that their actual ages are much greater than
their dynamical age (<10000 yr). We find that most of simple UC HII regions
previously known have large ratios of single-dish to VLA fluxes, similar to our
sources. Therefore, the `age problem' of UC HII regions does not seem to be as
serious as earlier studies argued. We present a simple model that explains
extended emission around UC HII regions. Some individual sources are discussed.

</DOC>
<DOC>
<DOCNO> 102178 </DOCNO>
Zariski theorems and diagrams for braid groups


  Empirical properties of generating systems for complex reflection groups and
their braid groups have been observed by Orlik-Solomon and
Brou\'e-Malle-Rouquier, using Shephard-Todd classification. We give a general
existence result for presentations of braid groups, which partially explains
and generalizes the known empirical properties. Our approach is
invariant-theoretic and does not use the classification. The two ingredients
are Springer theory of regular elements and a Zariski-like theorem.

</DOC>
<DOC>
<DOCNO> 68018 </DOCNO>
Stellar evolution and large extra dimensions


  We discuss in detail the information on large extra dimensions which can be
derived in the framework of stellar evolution theory and observation. The main
effect of large extra dimensions arises from the production of the Kaluza-Klein
(KK) excitations of the graviton. The KK-graviton and matter interactions are
of gravitational strength, so the KK states never become thermalized and always
freely escape. In this paper we first pay attention to the sun. Production of
KK gravitons is incompatible with helioseismic constraints unless the 4+n
dimensional Planck mass M_s exceeds 300 Gev/c^2. Next we show that stellar
structures in their advanced phase of H burning evolution put much more severe
constraints, M_s > 3-4 TeV/c^2, improving on current laboratory lower limits.

</DOC>
<DOC>
<DOCNO> 152181 </DOCNO>
Light-cone approach to eleven dimensional supergravity


  Manifestly supersymmetric formulation of eleven dimensional supergravity in
the framework of light-cone approach is discussed.

</DOC>
<DOC>
<DOCNO> 10508 </DOCNO>
Can Polymer Coils be modeled as "Soft Colloids"?


  We map dilute or semi-dilute solutions of non-intersecting polymer chains
onto a fluid of ``soft'' particles interacting via a concentration dependent
effective pair potential, by inverting the pair distribution function of the
centers of mass of the initial polymer chains. A similar inversion is used to
derive an effective wall-polymer potential; these potentials are combined to
successfully reproduce the calculated exact depletion interaction induced by
non-intersecting polymers between two walls. The mapping opens up the
possibility of large-scale simulations of polymer solutions in complex
geometries.

</DOC>
<DOC>
<DOCNO> 122213 </DOCNO>
Reconstruction of the Zone of Avoidance


  The uncovering of the large-scale structure that is hidden in the Zone of
Avoidance is essential to our quest for the understanding of the dynamics of
the nearby universe. Dedicated and sophisticated observations of the Zone of
Avoidance have to be matched by equally sophisticated theoretical tools for the
reconstruction of the large-scale structure from sparse, noisy and very
incomplete data. A general approach for the estimation of cosmological
parameters and the reconstruction of the density and velocity fields is
presented here, based on maximum likelihood analysis, Wiener filtering and
constrained realizations. Radial velocity surveys and the IRAS 1.2 Jy redshift
survey are used to reconstruct the Zone of Avoidance.

</DOC>
<DOC>
<DOCNO> 121936 </DOCNO>
Binary Stars in Young Clusters - a Theoretical Perspective


  The preponderance of binary systems in all known stellar populations makes
them exciting dynamical agents for research on topics as varied as star
formation, star-cluster dynamics and the interiors of young and old stars.
Today we know that the Galactic-field binary population is probably a
dynamically evolved version of the Taurus-Auriga pre-main sequence population,
and that the initial distributions of binary-star orbital elements are probably
universal. Furthermore, N-body calculations tentatively suggest that OB stars
form in energetic binaries near cluster cores, and that binaries with
'forbidden' orbital elements that are produced in stellar encounters, may turn
out to be very useful windows into stellar interiors, potentially allowing
tests of pre-main sequence evolution theory as well as of models of
main-sequence stars.

</DOC>
<DOC>
<DOCNO> 116624 </DOCNO>
Screened Coulomb potentials for astrophysical nuclear fusion reactions


  The electron-screening acceleration of laboratory fusion reactions at
astrophysical energies is an unsolved problem of great importance to
astrophysics. That effect is modeled here by considering the fusion of
hydrogen-like atoms whose electron probability density is used in Poisson's
equation in order to derive the corresponding screened Coulomb potential
energy. That way atomic excitations and deformations of the fusing atoms can be
taken into account. Those potentials are then treated semiclassically in order
to obtain the screening (accelerating) factor of the reaction. By means of the
proposed model the effect of a superstrong magnetic field on laboratory
Hydrogen fusion reactions is investigated here for the first time showing that,
despite the considerable increase in the cross section of the $% dd$ reaction,
the $pp$ reaction is still too slow to justify experimentation. The proposed
model is finally applied on the $H^{2}(d,p) H^{3}$ fusion reaction describing
satisfactorily the experimental data although some ambiguity remains regarding
the molecular nature of the deuteron target. Notably, the present method gives
a sufficiently high screening energy for Hydrogen fusion reactions so that the
take-away energy of the spectator nucleus can also be taken into account.

</DOC>
<DOC>
<DOCNO> 123270 </DOCNO>
Cosmic Data Fusion


  We compare and combine likelihood functions of the cosmological parameters
Omega_m, h and sigma_8 from the CMB, type Ia supernovae and from probes of
large scale structure. We include the recent results from the CMB experiments
BOOMERANG and MAXIMA-1. Our analysis assumes a flat LambdaCDM cosmology with a
scale-invariant adiabatic initial power spectrum. First we consider three data
sets that directly probe the mass in the Universe, without the need to relate
the galaxy distribution to the underlying mass via a `biasing' relation:
peculiar velocities, CMB and supernovae. We assume a baryonic fraction as
inferred from Big-Bang Nucleosynthesis and find that all three data sets agree
well, overlapping significantly at the 2-sigma level. This therefore justifies
a joint analysis, in which we find a joint best fit point and 95% confidence
limits of Omega_m=0.28 (0.17,0.39), h=0.74 (0.64,0.86), and sigma_8=1.17
(0.98,1.37). Secondly we extend our earlier work on combining CMB, supernovae,
cluster number counts, IRAS galaxy redshift survey data to include BOOMERANG
and MAXIMA-1 data and to allow a free Omega_b h^2. We find that, given our
assumption of a scale invariant initial power spectrum (n=1), we obtain the
robust result of Omega_b h^2= 0.031 +/- 0.03, which is dominated by the CMB
constraint.

</DOC>
<DOC>
<DOCNO> 10400 </DOCNO>
Superconducting Fluctuations and the Pseudogap in the Slightly-overdoped


  From measurements of the ^{63}Cu Knight shift (K) and the nuclear
spin-lattice relaxation rate (1/T_{1}) under magnetic fields from zero up to 28
T in the slightly overdoped superconductor TlSr_{2}CaCu_{2}O_{6.8} (T_{c}=68
K), we find that the pseudogap behavior, {\em i.e.}, the reductions of 1/T_{1}T
and K above T_{c} from the values expected from the normal state at high T, is
strongly field dependent and follows a scaling relation. We show that this
scaling is consistent with the effects of the Cooper pair density fluctuations.
The present finding contrasts sharply with the pseudogap property reported
previously in the underdoped regime where no field effect was seen up to 23.2
T. The implications are discussed.

</DOC>
<DOC>
<DOCNO> 69436 </DOCNO>
Induced theta-vacuum states in heavy ion collisions: a possible


  It has been suggested recently that an arbitrary induced theta-vacuum state
could be created in heavy ion collisions. If such a state can be created, it
would decay by various mechanisms to the fundamental theta=0 state which is the
true ground state of our world. In the following we will discuss the
possibility of studying this unusual state through the emission of pions,
eta-mesons, and eta'-mesons. We will also present the spectrum of the produced
particles in this non-zero theta background. We use the instantaneous
perturbation theory for our estimates.

</DOC>
<DOC>
<DOCNO> 40328 </DOCNO>
A search for resonance decays to antineutrino-jet in e^+p scattering at


  A study of the antineutrino-jet mass spectrum in e^+p -> antineutrino+X
events at center-of-mass energy 300 GeV has been performed with the ZEUS
detector at HERA using an integrated luminosity of 47.7 pb^-1. The mass
spectrum is in good agreement with that expected from Standard Model processes
over the antineutrino -jet mass range studied. No significant excess
attributable to the decay of a narrow resonance is observed. By using both e^+p
-> e^+ X and e^+p -> antineutrino X data, mass-dependent limits are set on the
s-channel production of scalar and vector resonant states. Couplings to
first-generation quarks are considered and limits are presented as a function
of the e^+q and antineutrino-q branching ratios. These limits are used to
constrain the production of leptoquarks and R-parity violating squarks.

</DOC>
<DOC>
<DOCNO> 170152 </DOCNO>
Probabilistic teleportation of two-particle entangled state


  In this letter, two different probabilistic teleportations of a two-particle
entangled state by pure entangled three-particle state are shown. Their
successful probabilities are different.

</DOC>
<DOC>
<DOCNO> 100364 </DOCNO>
Fermionic form and Betti numbers


  We state a conjectural relationship between the fermionic form (G. Hatayama,
A. Kuniba, M. Okado, T. Takagi, Y. Yamada qa/9812022) and the Betti numbers of
a Grassmannian over a preprojective algebra or, equivalently, of a lagrangian
quiver variety.

</DOC>
<DOC>
<DOCNO> 178606 </DOCNO>
Point-Form Analysis of Elastic Deuteron Form Factors


  Point-form relativistic quantum mechanics is applied to elastic
electron-deuteron scattering. The deuteron is modeled using relativistic
interactions that are scattering-equivalent to the nonrelativistic Argonne
$v_{18}$ and Reid '93 interactions. A point-form spectator approximation (PFSA)
is introduced to define a conserved covariant current in terms of
single-nucleon form factors. The PFSA is shown to provide an accurate
description of data up to momentum transfers of 0.5 ${\rm GeV}^2$, but falls
below the data at higher momentum transfers. Results are sensitive to the
nucleon form factor parameterization chosen, particularly to the neutron
electric form factor.

</DOC>
<DOC>
<DOCNO> 67888 </DOCNO>
On The tau --> a sub 1 h nu sub tau Decays


  The \tau \to (a_1 h)^- \nu_{\tau} decays of the \tau-lepton are studied using
the method of phenomenological chiral Lagrangians. The expression of weak
hadronic currents between pseudoscalar and axial-vector meson states is
obtained. Calculated partial widths for these decays are compared with the
available experimental data.

</DOC>
<DOC>
<DOCNO> 68801 </DOCNO>
The Radiative Leptonic $B_{c}\to \tau\bar{\nu_{\tau}}\gamma$ Decay in


  The radiative leptonic $B_{c}\to\tau\bar{\nu_{\tau}}\gamma$ decay is analysed
in context of 2HDM. It is shown that with large values of $tan\beta$, the
contributions of Model II to the decay rate exceeds considerably the Standard
Model ones, while the contributions of Model I overlap with the Standard Model
predictions.

</DOC>
<DOC>
<DOCNO> 150804 </DOCNO>
Nonlinear realization of superconformal symmetry and Liouville equation


  It is shown that the method of nonlinear realization of local supersymmetry
being applied to the n=(1,1) superconformal symmetry allows one reduce the new
version of the super-Liouville equation to the ordinary one owing to the
relaxation of the auxiliary equation of motion fixing the gauge parameters.

</DOC>
<DOC>
<DOCNO> 10781 </DOCNO>
Fragmentation with a Steady Source


  We investigate fragmentation processes with a steady input of fragments. We
find that the size distribution approaches a stationary form which exhibits a
power law divergence in the small size limit, P(x) ~ x^{-3}. This algebraic
behavior is robust as it is independent of the details of the input as well as
the spatial dimension. The full time dependent behavior is obtained
analytically for arbitrary inputs, and is found to exhibit a universal scaling
behavior.

</DOC>
<DOC>
<DOCNO> 118025 </DOCNO>
A Comparison of the Extra Nuclear X-ray and Radio Features in M87


  ROSAT High Resolution Imager (HRI) data from eight observations have been
co-added to obtain an effective exposure of 230 ksec. We have identified a
number of features and regions with excess X-ray brightness over that from a
circularly symmetric model of the well known hot gas component. A prominent
`spur' extends 4' from the vicinity of knot A towards the south-west. The
brightness to the south and east of this spur is significantly higher than that
to the north and west. Excess brightness is also found to the East of the
nucleus, with a local maximum centered on the eastern radio lobe 3' from the
core.
  There are two well known relationships between radio and x-ray emission for
radio galaxies in clusters: coincidence of emissions because the X-rays come
from inverse Compton or synchrotron processes; and anti-coincidence caused by
exclusion of hot gas from radio entities. We present a radio/X-ray comparison
to determine if either of these relationships can be isolated in M87. The
greatest obstacle we face is the unknown projection which affects both bands.

</DOC>
<DOC>
<DOCNO> 119965 </DOCNO>
WFPC2 Stellar Photometry with HSTphot


  HSTphot, a photometry package designed to handle the undersampled PSFs found
in WFPC2 images, is introduced and described, as well as some of the
considerations that have to be made in order to obtain accurate PSF-fitting
stellar photometry with WFPC2 data. Tests of HSTphot's internal reliability are
made using multiple observations of the same field, and tests of external
reliability are made by comparing with DoPHOT reductions of the same data.

</DOC>
<DOC>
<DOCNO> 116879 </DOCNO>
Energy Stability in a High Intensity Pulsed SC Proton Linac


  Spallation source dedicated for neutron scattering experiments, as well as
multi-purpose facilities serving several applications call for pulsed mode
operation of a high intensity proton linac. There is general agreement on the
superconducting technology for the high-energy part, which offers some
advantages, like higher gradient capabilities or operational costs reduction,
as compared to room-temperatures accelerating structures. This mode of
operation however could spoil the energy stability of the proton beam and needs
thus to be carefully studied. First, transient beam-loading effects, arising
from the large beam phase slippage along a multi-cell cavity and associated
with the finite RF energy propagation, can induce significant energy modulation
with a too small cell-to-cell coupling or a too large number of cells. Second,
due to beam phase slippage effects along the linac, energy spread exhibits a
larger sensitivity to cavity fields fluctuations than relativistic particles. A
computer code, initially developed for electron beams has been extended to
proton beams. It solves the 6xN coupled differential equations, needed to
describe cavity fields and beam-cavity interactions of a high-energy linac
composed of N cavities. Simulation examples on a typical pulsed accelerator are
given with various error sources, like Lorentz forces or microphonics detuning,
beam injection energy offsets, intensity jitters ...

</DOC>
<DOC>
<DOCNO> 116659 </DOCNO>
Monte Carlo study of the scattering error of a quartz reflective


  A Monte Carlo model was used to study the scattering error of an absorption
meter with a divergent light beam and a limited acceptance angle of the
receiver. Reflections at both ends of the tube were taken into account.
Calculations of the effect of varying optical properties of water, as well as
the receiver geometry, were performed. A weighting function showing the
scattering error quantitatively as a function of angle was introduced. Some
cases of the practical interests are discussed.

</DOC>
<DOC>
<DOCNO> 174539 </DOCNO>
Proton Emission Times in Spectator Fragmentation


  Proton-proton correlations from spectator decays following Au + Au collisions
at 1000 AMeV have been measured with an highly efficient detector hodoscope.
The constructed correlation functions indicate a moderate expansion and low
breakup densities similar to assumptions made in statistical multifragmentation
models. In agreement with a volume breakup rather short time scales were
deduced employing directional cuts in proton-proton correlations.

</DOC>
<DOC>
<DOCNO> 70255 </DOCNO>
Implications of the possibility that sin(2 beta) is small


  Recently, the Babar and Belle collaborations have reported their first
measurements of the CP-violating asymmetry in Bd --> psi KS, and more precise
results will follow soon. We discuss what a future evidence for small sin(2
beta) could mean, contrasting the usual possibility of new physics in the Bd
system, with the interesting alternative that the new physics effects are
confined to the kaon system.

</DOC>
<DOC>
<DOCNO> 40443 </DOCNO>
Observation of the $\Omega_{c}^{0}$ Charmed Baryon at CLEO


  The CLEO experiment at the CESR collider has used 13.7 fb$^{-1}$ of data to
search for the production of the $\Omega_c^0$ (css-ground state) in
$e^{+}e^{-}$ collisions at $\sqrt{s} \simeq 10.6$ {\rm GeV}. The modes used to
study the $\Omega_c^0$ are $\Omega^- \pi^+$,
  $\Omega^- \pi^+ \pi^0$, $\Xi^- K^- pi^+ \pi^+$, $\Xi^0 K^- pi^+$, and
$\Omega^- \pi^+ \pi^- \pi^+$. We observe a signal of 40.4$\pm$9.0(stat) events
at a mass of 2694.6$\pm$2.6(stat)$\pm$1.9(syst) {\rm MeV/$c^2$}, for all modes
combined.

</DOC>
<DOC>
<DOCNO> 9058 </DOCNO>
Critical State in Thin Anisotropic Superconductors of Arbitrary Shape


  A thin flat superconductor of arbitrary shape and with arbitrary in-plane and
out-of-plane anisotropy of flux-line pinning is considered, in an external
magnetic field normal to its plane.
 It is shown that the general three-dimensional critical state problem for this
superconductor reduces to the two-dimensional problem of an infinitely thin
sample of the same shape but with a modified induction dependence of the
critical sheet current. The methods of solving the latter problem are well
known. This finding thus enables one to study the critical states in realistic
samples of high-Tc superconductors with various types of anisotropic flux-line
pinning. As examples, we investigate the critical states of long strips and
rectangular platelets of high-Tc superconductors with pinning either by the
ab-planes or by extended defects aligned with the c-axis.

</DOC>
<DOC>
<DOCNO> 68303 </DOCNO>
Calculating three-loop diagrams in Heavy Quark Effective Theory with


  An algorithm for calculation of three-loop propagator diagrams in HQET, based
on integration-by-parts recurrence relations, is constructed and implemented as
a REDUCE package Grinder, and in Axiom.

</DOC>
<DOC>
<DOCNO> 119169 </DOCNO>
Testing Intermittency of the Galactic Star Formation History along with


  We analyze the star formation history (SFH) of the Galactic disk by using an
infall model. Based on the observed SFH of the Galactic disk, we first
determine the timescales of the gas infall into the Galactic disk ($t_{\rm
in}$) and that of the gas consumption to form stars ($t_{\rm sf}$). Since each
of the two timescales does not prove to be determined independently from the
SFH, we first fix $t_{\rm sf}$. Then, $t_{\rm in}$ is determined so that we
minimize $\chi^2$. Consequently, we choose three parameter sets: ($t_{\rm sf}$
[Gyr], $t_{\rm in}$ [Gyr]) = (6.0, 23), (11, 12), and (15, 9.0), where we set
the Galactic age as 15 Gyr. All of the three cases predict almost identical
star formation history. Next, we test the intermittency (or variability) of the
star formation rate (SFR) along with the smooth SFH suggested from the infall
model. The large value of the $\chi^2$ statistic supports the violent
time-variation of the SFH. If we interpret the observed SFH with smooth and
variable components, the amplitude of the variable component is comparable to
the smooth component. Thus, intermittent SFH of the Galactic disk is strongly
suggested. We also examined the metallicity distribution of G-dwarfs. We found
that the true parameter set lies between ($t_{\rm sf}$ [Gyr], $t_{\rm in}$
[Gyr]) = (6, 23) and (11, 12), though we should need a more sophisticated model
including the process of metal enrichment within the Galactic halo.

</DOC>
<DOC>
<DOCNO> 117715 </DOCNO>
ROSAT observations of X-ray emission from planetary nebulae


  We have searched the entire ROSAT archive for useful observations to study
X-ray emission from Galactic planetary nebulae (PNs). The search yields a
sample of 63 PNs, which we call the ROSAT PN sample. About 20-25% of this
sample show X-ray emission; these include 13 definite detections and three
possible detections (at a 2-sigma level). All X-ray sources in these PNs are
concentrated near the central stars. Only A 30, BD+30 3639, and NGC 6543 are
marginally resolved by the ROSAT instruments. Three types of X-ray spectra are
seen in PNs. Type 1 consists of only soft X-ray emission (<0.5 keV), peaks at
0.1-0.2 keV, and can be fitted by blackbody models at temperatures 1-2 10^5 K.
Type 2 consists of harder X-ray emission, peaks at >0.5 keV, and can be fitted
by thin plasma emission models at temperatures of a few 10^6 K. Type 3 is a
composite of a bright Type 1 component and a fainter Type 2 component.
Unresolved soft sources with Type 1 spectra or the soft component of Type 3
spectra are most likely photospheric emission from the hot central stars.
Absorption cross sections are large for these soft-energy photons; therefore,
only large, tenuous, evolved PNs with hot central stars and small absorption
column densities have been detected. The origin of hard X-ray emission from PNs
is uncertain. PNs with Type 2 spectra are small, dense, young nebulae with
relatively cool (<<10^5 K) central stars, while PNs with Type 3 X-ray spectra
are large, tenuous, evolved nebulae with hot central stars. The hard X-ray
luminosities are also different between these two types of PNs, indicating
perhaps different origins of their hard X-ray emission. Future Chandra and XMM
observations with high spatial and spectral resolution will help to understand
the origin of hard X-ray emission from PNs.

</DOC>
<DOC>
<DOCNO> 178553 </DOCNO>
On a Theory of Superfluidity of Asymmetric Nuclear Matter


  Influence of asymmetry on superfluidity of nuclear matter with
triplet-singlet pairing of nucleons (in spin and isospin spaces) is considered
within the framework of a Fermi-liquid theory. Solutions of self-consistent
equations for the critical temperature and the energy gap at T=0 are obtained.
It is shown, that the backward influence of pairing correlations through the
normal distribution functions of nucleons leads to the qualitative change:
instead of two-valued behavior the energy gap has universal one-valued
behavior. At T=0 superfluidity arises as a result of a first order phase
transition in density.

</DOC>
<DOC>
<DOCNO> 101922 </DOCNO>
Some p-adic differential equations


  We investigate various properties of p-adic differential equations which have
as a solution an analytic function of the form $F_k (x) = \sum_{n\geq 0} n! P_k
(n) x^n$, where $P_k (n) = n^k + C_{k-1} n^{k-1} + ...+ C_0$ is a polynomial in
n with $C_i\in Z$ (in a more general case $C_i\in Q$ or $C_i\in C_p$). For some
special classes of $P_k (n)$, as well as for the general case, the existence of
the corresponding linear differential equations of the first- and second-order
for $F_k (x)$, is shown. In some cases such equations are constructed. For the
second-order differential equations there is no other analytic solution of the
form $\sum a_n x^n$. Due to the fact that the corresponding inhomogeneous
first-order differential equation exists one can construct infinitely many
inhomogeneous second-order equations with the same analytic solution. Relation
to some rational sums with the Bernoulli numbers and to $F_k (x)$ for some
$x\in Z$ is considered. Some of these differential equations can be related to
p-adic dynamics and p-adic information theory.

</DOC>
<DOC>
<DOCNO> 13314 </DOCNO>
Protein Unfolding and the Diffusion Collision Model


  In the diffusion-collision model, the unfolding or backward rates are given
by the likelihood of secondary structural cluster dissociation. In this work,
we introduce a backward rate calculation modeled from a Kramers-type thermal
tunneling through a barrier, which represents the free energy potential well
for buried hydrophobic residues. Our results are in good agreement with
currently accepted values and the approach suggests a link between the
diffusion-collision and folding funnel models of protein folding.

</DOC>
<DOC>
<DOCNO> 151189 </DOCNO>
Scalar field theories in a Lorentz-invariant three-dimensional


  We discuss scalar quantum field theories in a Lorentz-invariant
three-dimensional noncommutative space-time. We first analyze the one-loop
diagrams of the two-point functions, and show that the non-planar diagrams are
finite and have infrared singularities from the UV/IR mixing. The scalar
quantum field theories have the problem that the violation of the momentum
conservation from the non-planar diagrams does not vanish even in the
commutative limit. A way to obtain an exact translational symmetry by
introducing an infinite number of tensor fields is proposed. The translational
symmetry transforms local fields into non-local ones in general. We also
discuss an analogue of thermodynamics of free scalar field theory in the
noncommutative space-time.

</DOC>
<DOC>
<DOCNO> 116640 </DOCNO>
Twin paradox and space topology


  If space is compact, then a traveller twin can leave Earth, travel back home
without changing direction and find her sedentary twin older than herself. We
show that the asymmetry between their spacetime trajectories lies in a
topological invariant of their spatial geodesics, namely the homotopy class.
This illustrates how the spacetime symmetry invariance group, although valid
{\it locally}, is broken down {\it globally} as soon as some points of space
are identified. As a consequence, any non--trivial space topology defines
preferred inertial frames along which the proper time is longer than along any
other one.

</DOC>
<DOC>
<DOCNO> 119066 </DOCNO>
EUVE Observations of OY Carinae in Superoutburst


  The Extreme Ultraviolet Explorer (EUVE) satellite was used for three days
beginning on 1997 Mar 26.96 UT to obtain photometric and spectroscopic
observations of the eclipsing SU UMa-type dwarf nova OY Carinae in
superoutburst. Because of the longer time on source (143 ks), the larger number
of eclipses observed (17), and the higher count rate in the detector (0.5-2.2
counts/s), we are able to significantly strengthen previous reports that there
is little or no eclipse by the secondary of the EUV emission region of OY Car
in superoutburst. The mean EUVE spectrum extends from 70 to 190 A and contains
broad (FWHM~1 A) emission lines of N V, O V-O VI, Ne V-Ne VII, Mg IV-Mg VI, Fe
VI-Fe VIII, and possibly Fe XXIII. Good fits of the observed spectrum are
obtained with a model (similar to that of Seyfert 2 galaxies) wherein radiation
from the boundary layer and accretion disk is scattered into the line of sight
by the system's photoionized accretion disk wind. It is possible to trade off
continuum luminosity for wind optical depth, but reasonable models have a
boundary layer temperature T_{bl}=90-130 kK and a boundary layer and accretion
disk luminosity L_{bl}=L_{disk} ~4x10^{34} erg/s ~ 10 Lsun, corresponding to a
mass-accretion rate Mdota~10^{-8} Msun/yr; an absorbing column density
N_H=1.6-3.5x10^{19} cm^{-2}; and a wind mass-loss rate Mdotw~10^{-10} Msun/yr ~
0.01 Mdota. Because radiation pressure alone falls an order of magnitude short
of driving such a wind, magnetic forces must also play a role in driving the
wind of OY Car in superoutburst.

</DOC>
<DOC>
<DOCNO> 121387 </DOCNO>
A 421 d Activity Cycle in the BeX Recurrent Transient A0538-66 from


  We present a ~ 5-yr optical light curve of the recurrent Be/X-ray transient
A0538-66 obtained as a by-product of the MACHO Project. These data reveal both
a long-term modulation at P = 420.8 +/- 0.8 d and a short-term modulation at
16.6510 +/- 0.0022 d which, within errors, confirms the previously found
orbital period. Furthermore, the orbital activity is only seen at certain
phases of the 421 d cycle suggesting that the long-term modulation is related
to variations in the Be star envelope.

</DOC>
<DOC>
<DOCNO> 102305 </DOCNO>
A non-automatic (!) application of Gosper's algorithm evaluates a


  We evaluate the determinant $\det_{1\leq i,j\leq
n}(\binom{x+y+j}{x-i+2j}-\binom{x+y+j}{x+i+2j})$, which gives the number of
lozenge tilings of a hexagon with cut off corners. A particularly interesting
feature of this evaluation is that it requires the proof of a certain
hypergeometric identity which we accomplish by using Gosper's algorithm in a
non-automatic fashion.

</DOC>
<DOC>
<DOCNO> 151832 </DOCNO>
Constrained Quantization of Charged Strings in Background B Field and


  The Dirac quantization is performed for the constrained system of the open
string with different charges located at both ends in the constant background B
field. Noncommutativity reveals to commutators [X, X], [P, P] and also [X,P] at
both ends of the string. We consider a dependence on the change of the
"cyclotron frequency" of the charged string. The g-factor of the charged string
is also calculated in the framework of our formulation.

</DOC>
<DOC>
<DOCNO> 68083 </DOCNO>
Radiative corrections to e+e- --> f+f-


  The past ten years of physics with e+e- colliding experiments at LEP and SLAC
have shown the success of these experiments on not only impressively proving
the theoretical predictions of the Standard Model (SM), but also to help
provide stringent bounds on physics beyond the SM. With this experience in
mind, there appear two equally fascinating opportunities for studying
fermion-pair production processes at a future Linear Collider (LC). On the one
hand, performing high precision measurements to the SM, for example, when
running with high luminosity at the Z boson resonance, could be a quick and
feasible enterprise in order to pin down the symmetry breaking mechanism of the
electroweak sector through indirectly determining the masses of a light SM or
MSSM Higgs boson or supersymmetric particles via virtual corrections. On the
other hand, looking for such particles in direct production or other `New
Physics' effects at energies between, for example, roughly 500 and 800 GeV will
naturally be the main motivation to pursue the challenging endeavor of building
and utilizing such a unique facility. These two scenarios for the LC shall be
sketched here, with particular emphasis on the semi-analytical program ZFITTER
for fermion-pair production in comparison with numerical programs like TOPAZ0,
KK2f, and others.

</DOC>
<DOC>
<DOCNO> 70646 </DOCNO>
Effective Quark Models in QCD at low and intermediate energies


  The effective quark models are employed to describe the hadronization of QCD
in the quark sector. They reveal a different structure depending on how the
spontaneous chiral symmetry breaking (CSB) is implemented. When the generation
of light pseudoscalar mesons is manifestly incorporated one deals with an
extension of the chiral quark model (CQM) with the non-linear realization of
chiral symmetry. If a model is built at the CSB scale by means of perturbation
theory it generalizes the Nambu-Jona-Lasinio (NJL) one with chiral symmetry
broken due to attractive 4-fermion forces in the scalar channel. The matching
to high-energy QCD is realized at CSB scale by means of Chiral Sum Rules. Two
types of models are compared in their fitting of meson physics. In particular,
if the lowest scalar meson is sufficiently heavy approaching the mass of heavy
\pi'(1300) then QCD favours an effective theory which is dominated by the
simplest CQM. On the contrary, the light scalar quarkonium with a mass of order
500MeV, supports the NJL mechanism.

</DOC>
<DOC>
<DOCNO> 122685 </DOCNO>
Gravitational lensing in galaxy redshift surveys


  Gravitationally-lensed quasars should be discovered as a by-product of large
galaxy redshift surveys, being discovered spectroscopically when a low-redshift
galaxy exhibits high-redshift quasar emission lines. The number of lenses
expected is higher than previously estimated, mainly due to the fact that the
presence of the quasar images brings faint deflector galaxies above the survey
limit. Thus the a posteriori likelihood of the discovery of Q 2237+0305 in the
Center for Astrophysics redshift survey is approximately 0.03. In the future,
the 2 degree Field survey should yield at least 10 lensed quasars, and the
Sloan Digitial Sky Survey up to 100.

</DOC>
<DOC>
<DOCNO> 122736 </DOCNO>
Turbulent Fragmentation and the Initial Conditions for Star Formation


  Super-sonic turbulence fragments molecular clouds (MC) into a very complex
density field with density contrasts of several orders of magnitude. A fraction
of the gas is locked into dense and gravitationally bound cores, which collapse
as proto-stars. This process can be studied with numerical simulations of
super-sonic self-gravitating turbulence.
  In this work, we use numerical simulations of magneto-hydrodynamic (MHD),
super-sonic, super-Alfv\'{e}nic and self-gravitating turbulence to compute the
mass distribution of collapsing proto-stellar cores, which are selected as
local density maxima. We find that the mass distribution of collapsing cores is
consistent with the stellar initial mass function (IMF), suggesting that
super-sonic turbulence may be responsible for the generation of the IMF.
  To support this conclusion we also show that the physical properties of the
numerically selected cores are in agreement with the properties of observed
NH$_3$ cores and that their magnetic field strength is consistent with Zeeman
splitting measurements.
  In turbulent MCs, star formation occurs via the gravitational collapse of
super-critical cores, formed by the turbulent flow, sub-critical cores being
irrelevant for the process of star formation.

</DOC>
<DOC>
<DOCNO> 122833 </DOCNO>
Inner Disk Oscillations and QPOs in Relativistic Jet Sources


  Recent results on the inner disk oscillations found in GRS 1915+105 are
reviewed. QPOs during the low state are used as a marker for such oscillations
and the physical picture emerging from a combined X-ray spectral and timing
analysis is examined. The relationship between inner disk oscillations and
synchrotron radio emission is critically evaluated.

</DOC>
<DOC>
<DOCNO> 9478 </DOCNO>
Vertical Melting of a Stack of Membranes


  A stack of tensionless membranes with nonlinear curvature energy and vertical
harmonic interaction is studied. At low temperatures, the system forms a
lamellar phase. At a critical temperature, the stack disorders vertically in a
melting-like transition.

</DOC>
<DOC>
<DOCNO> 119783 </DOCNO>
An Exploration of the Paradigm for the 2-3 Hour Period Gap in


  We critically examine the basic paradigm for the origin of the 2-3 hr period
gap in cataclysmic variables (CVs). We carry out an extensive population
synthesis study of CVs starting from ~ 3 x 10^6 primordial binaries, and
evolving some ~ 2 x 10^4 surviving systems through their CV phase. In
particular we study current-epoch distributions of CVs in the $\dot M-P_{orb}$,
R_{2}-P_{orb}, M_{2}-P_{orb}, q-P_{orb}, T_{eff}-P_{orb}, and L_{2}-P_{orb}
planes, where $\dot M$ is the mass transfer rate, q is the mass ratio M_2/M_1,
and M_2, R_2, T_{eff}, and L_2 are the donor star mass, radius, effective
temperature, and luminosity, respectively. This work presents a new perspective
on theoretical studies of the long-term evolution of CVs. In particular, we
show that if the current paradigm is correct, the secondary masses in CVs just
above the period gap should be as much as ~ 50% lower than would be inferred if
one assumes a main-sequence radius-mass relation for the donor star.

</DOC>
<DOC>
<DOCNO> 10947 </DOCNO>
Exact Expressions for Minor Hysteresis Loops in the Random Field Ising


  Exact expressions for minor hysteresis loops have been obtained for the
random field Ising model on a Bethe lattice of arbitrary coordination number z
at zero temperature by generalizing the earlier result for z=2
(cond-mat/0004125).

</DOC>
<DOC>
<DOCNO> 69782 </DOCNO>
Dark matter phase space densities


  The low velocity part of a kinetic equilibrium dark matter distribution has
higher phase space density and is more easily incorporated in formation of a
low mass galaxy than the high velocity part. For relativistically decoupling
fermions (bosons), this explains one (two) orders of magnitude of the observed
trend, that phase space densities in dark matter halo cores are highest in the
smallest systems, and loosens constraints on particle masses significantly. For
non-relativistic decoupling and/or finite chemical potentials even larger
effects may occur. It is therefore premature to dismiss dissipationless
particle distributions as dark matter on the basis of phase space arguments.

</DOC>
<DOC>
<DOCNO> 101901 </DOCNO>
Connections up to homotopy and characteristic classes


  In this note we clarify the relevance of ``connections up to homotopy'' to
the theory of characteristic classes. We have already remarked \cite{Crai} that
such connections up to homotopy can be used to compute the classical Chern
characters. Here we present a slightly different argument for this, and then
proceed with the discussion of the flat (secondary) characteristic classes. As
an application, we clarify the relation between the two different approaches to
characteristic classes of algebroids (and of Poisson manifolds in particular):
we explain that the intrinsic characteristic classes are precisely the
secondary classes of the adjoint representation.

</DOC>
<DOC>
<DOCNO> 118529 </DOCNO>
TeV Gamma Rays from BL Lac Objects due to Synchrotron Radiation of


  One of remarkable features of the gamma ray blazar Markarian 501 is the
reported shape of the TeV spectrum, which during strong flares of the source
remains essentially stable despite dramatic variations of the absolute
gamma-ray flux. I argue that this (to a large extent unexpected) behavior of
the source could be explained assuming that the TeV gamma-ray emission is a
result of synchrotron radiation of extremely high energy protons in highly
magnetized compact regions of the jet.

</DOC>
<DOC>
<DOCNO> 170319 </DOCNO>
Approximation Errors


  A bound on the error introduced by truncating a quantum addition is given.
This bound shows that only a few controlled rotation gates will be necessary to
get a reliable computation.

</DOC>
<DOC>
<DOCNO> 84491 </DOCNO>
Non-Abelian Einstein-Born-Infeld Black Holes


  We construct regular and black hole solutions in SU(2) Einstein-Born-Infeld
theory. These solutions have many features in common with the corresponding
SU(2) Einstein-Yang-Mills solutions. In particular, sequences of neutral
non-abelian solutions tend to magnetically charged limiting solutions, related
to embedded abelian solutions. Thermodynamic properties of the black hole
solutions are addressed.

</DOC>
<DOC>
<DOCNO> 69466 </DOCNO>
Photon structure at HERA


  The structure of the virtual photon and its contribution to small x processes
in deep inelastic scattering at HERA is discussed.

</DOC>
<DOC>
<DOCNO> 101735 </DOCNO>
On a construction of Friedman


  H. Friedman obtained remarkable results about the longest finite sequence $x$
such that for all $i \not= j$ the word $x[i..2i]$ is not a subsequence of
$x[j..2j]$. In this note we consider what happens when ``subsequence'' is
replaced by ``subword''.

</DOC>
<DOC>
<DOCNO> 122538 </DOCNO>
The Tully-Fisher Relation as a Measure of Luminosity Evolution: A Low


  We use optical rotation curves to investigate the R-band Tully-Fisher
properties of a sample of 90 spiral galaxies in close pairs. The galaxies
follow the Tully-Fisher relation remarkably well, with the exception of eight
distinct 3-sigma outliers. Although most of the outliers show signs of recent
star formation, gasdynamical effects are probably the dominant cause of their
anomalous Tully-Fisher properties. Four outliers with small emission line
widths have very centrally concentrated line emission and truncated rotation
curves; the central emission indicates recent gas infall after a close
galaxy-galaxy pass. These four galaxies may be local counterparts to compact,
blue galaxies at intermediate redshift. The remaining galaxies have a
negligible offset from the reference Tully-Fisher relation, but a shallower
slope (2.6-sigma significance) and a 25% larger scatter. We characterize the
non-outlier sample with measures of distortion and star formation to search for
third parameter dependence in the residuals of the TF relation. Severe
kinematic distortion is the only significant predictor of TF residuals; this
distortion is not, however, responsible for the slope difference from the
reference distribution.
  Because the outliers are easily removed by sigma clipping, we conclude that
even in the presence of some tidal distortion, detection of moderate luminosity
evolution should be possible with high-redshift samples the size of this
90-galaxy study. (Abridged.)

</DOC>
<DOC>
<DOCNO> 85566 </DOCNO>
Properties of the instantaneous Ergo Surface of a Kerr Black Hole


  This paper explores properties of the instantaneous ergo surface of a Kerr
black hole. The surface area is evaluated in closed form. In terms of the mass
($m$) and angular velocity ($a$), to second order in $a$, the area of the ergo
surface is given by $16 \pi m^2 + 4 \pi a^2$ (compared to the familiar $16 \pi
m^2 - 4 \pi a^2$ for the event horizon). Whereas the total curvature of the
instantaneous event horizon is $4 \pi$, on the ergo surface it ranges from $4
\pi$ (for $a=0$) to 0 (for $a=m$) due to conical singularities on the axis
($\theta=0,\pi$) of deficit angle $2 \pi (1-\sqrt{1-(a/m)^2})$. A careful
application of the Gauss-Bonnet theorem shows that the ergo surface remains
topologically spherical. Isometric embeddings of the ergo surface in Euclidean
3-space are defined for $0 \leq a/m \leq 1$ (compared to $0 \leq a/m \leq
\sqrt{3}/2$ for the horizon).

</DOC>
<DOC>
<DOCNO> 70022 </DOCNO>
Linear Collider Physics


  Studies of the physics potential of the Future Linear Collider are
establishing a broad programme which will start in the region of 350 to 500 GeV
C. of M. energy. The main goal is to understand why the standard model works;
by studying the properties of the Higgs sector, if it is within reach, and by
exploring the complex world of Supersymmetry, if it is real. If the Higgs boson
is not found soon, then the Linear Collider can test the standard model with
high precision measurements, both at energies approaching 1 TeV and with high
statistics at the Z0.

</DOC>
<DOC>
<DOCNO> 99310 </DOCNO>
On some Moment Maps and Induced Hopf Bundles in the Quaternionic


  We describe a diagram containing the zero sets of the moment maps associated
to the diagonal U(1) and Sp(1) actions on the quaternionic projective space
HP^n. These sets are related both to focal sets of submanifolds and to
Sasakian-Einstein structures on induced Hopf bundles. As an application, we
construct a complex structure on the Stiefel manifolds V_2 (C^{n+1}) and V_4
(R^{n+1}), the one on the former manifold not being compatible with its known
hypercomplex structure.

</DOC>
<DOC>
<DOCNO> 68149 </DOCNO>
Future prospects for CP violation in hadron machines


  The capabilities of future CP violation experiments in hadron machines are
reviewed. Special emphasis is put on the CDF experiment in the run II of the
Tevatron, due to start taking data in 2001, and on LHCb and BTeV, on a longer
time scale.

</DOC>
<DOC>
<DOCNO> 169598 </DOCNO>
Optical Fock-state synthesizer


  We suggest a tunable optical device to synthesize Fock states and their
superpositions starting from a coherent source. The scheme involves an
avalanche triggering photodetector and a ring cavity coupled to a traveling
wave through a cross-Kerr medium. Low quantum efficiency at the photodetector
improves the synthesizing quality at the expense of reducing the synthesizing
rate.

</DOC>
<DOC>
<DOCNO> 122046 </DOCNO>
The Reionization of the Universe by the First Stars and Quasars


  The first light from stars and quasars ended the ``dark ages'' of the
universe and led to the reionization of hydrogen by redshift 7. Current
observations are at the threshold of probing this epoch. The study of
high-redshift sources is likely to attract major attention in observational and
theoretical cosmology over the next decade.

</DOC>
<DOC>
<DOCNO> 67939 </DOCNO>
Strangeness Form Factors of the Proton in the Chiral Quark Model


  The chiral quark model describes the strangeness components of the light
quarks as fluctuations into strange mesons and quarks. The single strange
pseudoscalar and vector meson loop fluctuations of the constituent $u$- and
$d$-quarks give rise to only very small strangeness form factors for the
proton. This result is in line with recent experimental results, given their
wide uncertainty range.

</DOC>
<DOC>
<DOCNO> 40591 </DOCNO>
Unitarity and geometrical aspects at low x


  On the grounds of extension of the U-matrix unitarization to the off-shell
scattering we consider virtual-photon induced scattering. We discuss behavior
of the structure function F_2(x,Q^2) at low x and the total cross-section of
virtual-photon proton scattering and obtain, in particular, the dependence
sigma^{tot}_{gamma^*p}\sim(W^2)^{lambda(Q^2)}, where exponent lambda(Q^2) is
related to the interaction radius of a virtual constituent quark.

</DOC>
<DOC>
<DOCNO> 101054 </DOCNO>
Combinatorial model categories have presentations


  We show that every combinatorial model category can be obtained, up to
Quillen equivalence, by localizing a model category of diagrams of simplicial
sets. This says that any combinatorial model category can be built up from a
category of `generators' and a set of `relations'---that is, any combinatorial
model category has a presentation.

</DOC>
<DOC>
<DOCNO> 170385 </DOCNO>
Eavesdropper's Optimal Information in Variations of Bennett-Brassard


  We calculate eavesdropper's optimal information on raw bits in
Bennett-Brassard 1984 quantum key distribution (BB84 QKD) and six-state scheme
in coherent attacks, using a formula by Lo and Chau [Science 283 (1999) 2050]
with single photon assumption. We find that eavesdropper's optimal information
in QKD without public announcement of bases [Phys. Lett. A 244 (1998) 489] is
the same as that of a corresponding QKD WITH it in the coherent attack. We
observe a sum-rule concerning each party's information.

</DOC>
<DOC>
<DOCNO> 70954 </DOCNO>
The (gamma^*-q\bar q)-Reggeon Vertex in Next-to-Leading Order QCD


  As a first step towards the computation of the NLO corrections to the photon
impact factor in the $\gamma^*\gamma^* \to \gamma^* \gamma^*$ scattering
process, we calculate the one loop corrections to the coupling of the reggeized
gluon to the $\gamma^*\to q\bar{q}$ vertex. We list the results for the Feynman
diagrams which contribute: all loop integrations are carried out, and the
results are presented in the helicity basis of photon, quark, and antiquark.

</DOC>
<DOC>
<DOCNO> 119224 </DOCNO>
Properties of Cosmic Shock Waves in Large Scale Structure Formation


  We have examined the properties of shock waves in simulations of large scale
structure formation for two cosmological scenarios (a SCDM and a LCDM with
Omega =1). Large-scale shocks result from accretion onto sheets, filaments and
Galaxy Clusters (GCs) on a scale of circa 5 Mpc/h in both cases. Energetic
motions, both residual of past accretion history and due to current asymmetric
inflow along filaments, generate additional, common shocks on a scale of about
1 Mpc/h, which penetrate deep inside GCs. Also collisions between substructures
inside GCs form merger shocks. Consequently, the topology of the shocks is very
complex and highly connected. During cosmic evolution the comoving shock
surface density decreases, reflecting the ongoing structure merger process in
both scenarios. Accretion shocks have very high Mach numbers (10-10^3), when
photo-heating of the pre-shock gas is not included. The typical shock speed is
of order v_{sh}(z) =H(z)lambda_{NL}(z), with lambda_{NL}(z) the wavelength
scale of the nonlinear perturbation at the given epoch. However, the Mach
number for shocks occuring within clusters is usually smaller (3-10), due to
the fact that the intracluster gas is already hot. Statistical fits of shock
speed around GCs as a function of GCs temperature give power-law's in accord
with 1-D predictions. However, a very different result is obtained for fits of
the shock radius, reflecting the very complex shock structures forming in 3-D
simulations. The in-flowing kinetic energy across such shocks, giving the power
available for cosmic-ray acceleration, is comparable to the cluster X-ray
luminosity emitted from a central region of radius 0.5 Mpc/h. Considering their
large size and long lifetimes, those shocks are potentially interesting sites
for cosmic-ray acceleration, if modest magnetic fields exist within them.

</DOC>
<DOC>
<DOCNO> 150999 </DOCNO>
On gauge fields - strings duality as an integrable system


  It was suggested in hep-th/0002106, that semiclassically, a partition
function of a string theory in the 5 dimensional constant negative curvature
space with a boundary condition at the absolute satisfy the loop equation with
respect to varying the boundary condition, and thus the partition function of
the string gives the expectation value of a Wilson loop in the 4 dimensional
QCD. In the paper, we present the geometrical framework, which reveals that the
equations of motion of such string theory are integrable, in the sense that
they can be written via a Lax pair with a spectral parameter. We also show,
that the issue of the loop equation rests solely on the properly posing the
boundary condition.

</DOC>
<DOC>
<DOCNO> 72140 </DOCNO>
(De)Stabilization of an extra dimension due to a Casimir force


  We study the stabilization of one spatial dimension in (p+1+1)-dimensional
spacetime in the presence of $p$-dimensional brane(s), a bulk cosmological
constant and the Casimir force generated by a conformally coupled scalar field.
We find general static solutions to the metric which require the fine-tuning of
the inter-brane distance and the bulk cosmological constant (leaving the two
brane tensions as free parameters) corresponding to a vanishing effective
cosmological constant and a constant radion field. Taking these solutions as a
background configuration, we perform a dimensional reduction and study the
effective theory in the case of one- and two-brane configurations. We show that
the radion field can have a positive mass squared, which corresponds to a
stabilization of the extra dimension, only for a repulsive nature of the
Casimir force. This type of solution requires the presence of a negative
tension brane. The solutions with one or two positive tension branes arising in
this theory turn out to have negative radion mass squared, and therefore are
not stable.

</DOC>
<DOC>
<DOCNO> 122471 </DOCNO>
How to get less helium and more neutrinos from BBN


  We discuss BBN in the presence of a non-minimally coupled quintessence model.
In some of these models, the gravitational constant and cosmic expansion rate
are smaller than standard model predicts. The Helium abundance is then smaller,
possibly resolve the marginal disagreement between theory and observation.
Furthermore, the constraint on neutrino species may also be relaxed.

</DOC>
<DOC>
<DOCNO> 150541 </DOCNO>
N=2 Supersymmetric Kinks and real algebraic curves


  The kinks of the (1+1)-dimensional Wess-Zumino model with polynomic
superpotential are investigated and shown to be related to real algebraic
curves.

</DOC>
<DOC>
<DOCNO> 8676 </DOCNO>
Growth of Monodispersed Colloids by Aggregation of Nucleating Subunits


  Formation of monodispersed colloidal particles is a complex process: nuclei,
produced rapidly in a supersaturated solution, grow to nanosize primary
particles, which then aggregate (coagulate) to form much larger final colloids.
This paper reviews a kinetic model that explains the formation of dispersions
of narrow size distribution in such processes. Numerical simulations of the
kinetic equations, with experimental model parameter values, are reported. The
model was tested for a system involving formation of uniform spherical gold
particles. The calculated average size, the width of the particle size
distribution, and the time scale of the process, agreed semiquantitatively with
the experimental values.

</DOC>
<DOC>
<DOCNO> 152457 </DOCNO>
Supergravity Duals for N=2 Gauge Theories


  We construct supergravity solutions for Dp-branes at orbifold points. The
solutions are written in terms of a single function, which is the solution to a
nonlinear differential equation. The near horizon limits of these solutions are
dual, in the AdS/CFT sense, to super-Yang-Mills theories with 8 supercharges in
various dimensions. In particular, we present a dual to N=2 SU(N) SYM theory in
3+1 dimensions, and analyse some aspects of the duality.

</DOC>
<DOC>
<DOCNO> 151888 </DOCNO>
Gauge-invariant formulation of the d=3 Yang-Mills theory


  We write down the Yang-Mills partition function and the average Wilson loop
in terms of local gauge-invariant variables being the six components of the
metric tensor of dual space. The Wilson loop becomes the trace of the parallel
transporter in curved space, else called the gravitational holonomy. We show
that the external coordinates mapping the 3d curved space into a flat 6d space
play the role of glueball fields, and there is a natural mechanism for the mass
gap generation.

</DOC>
<DOC>
<DOCNO> 71123 </DOCNO>
The Influence of Dimension Eight Operators on Weak Matrix Elements


  I describe recent work with V. Cirigliano and E. Golowich on the effect of
dimension eight operators on weak nonleptonic amplitudes. The basic message is
that there is an inconsistency in the way that many calculations are
traditionally performed. If one calculates matrix elements involving only
physics below some scale \mu, then one needs dimension eight operators
explicitly in the weak OPE. On the other hand if one wants to use dimensional
regularization throughout, then one needs all scales to be included within the
matrix element, and this results in the same net effect. A numerical estimate
indicates that this is important below \mu= 2 GeV, and this calls into question
many of the models that have been used to predict \epsilon'/\epsilon.

</DOC>
<DOC>
<DOCNO> 70172 </DOCNO>
Large CP violation in radiative B decays in supersymmetry without


  We demonstrate that the R-parity breaking interactions within their current
experimental upper bounds can give rise to large mixing-induced CP asymmetry in
exclusive radiative B decays that may be detectable in the upcoming B
factories.

</DOC>
<DOC>
<DOCNO> 170174 </DOCNO>
Bayesian Inverse Quantum Theory


  A Bayesian approach is developed to determine quantum mechanical potentials
from empirical data. Bayesian methods, combining empirical measurements and "a
priori" information, provide flexible tools for such empirical learning
problems. The paper presents the basic theory, concentrating in particular on
measurements of particle coordinates in quantum mechanical systems at finite
temperature. The computational feasibility of the approach is demonstrated by
numerical case studies. Finally, it is shown how the approach can be
generalized to such many-body and few-body systems for which a mean field
description is appropriate. This is done by means of a Bayesian inverse
Hartree-Fock approximation.

</DOC>
<DOC>
<DOCNO> 101965 </DOCNO>
su(N) tensor product multiplicities and virtual Berenstein-Zelevinsky


  Information on su(N) tensor product multiplicities is neatly encoded in
Berenstein-Zelevinsky triangles. Here we study a generalisation of these
triangles by allowing negative as well as non-negative integer entries. For a
fixed triple product of weights, these generalised Berenstein-Zelevinsky
triangles span a lattice in which one may move by adding integer linear
combinations of so-called virtual triangles. Inequalities satisfied by the
coefficients of the virtual triangles describe a polytope. The tensor product
multiplicities may be computed as the number of integer points in this convex
polytope. As our main result, we present an explicit formula for this
discretised volume as a multiple sum. As an application, we also address the
problem of determining when a tensor product multiplicity is non-vanishing. The
solution is represented by a set of inequalities in the Dynkin labels. We also
allude to the question of when a tensor product multiplicity is greater than a
given non-negative integer.

</DOC>
<DOC>
<DOCNO> 178731 </DOCNO>
Diabatic Mean-Field Description of Rotational Bands in Terms of the


  Diabatic description of rotational bands provides a clear-cut picture for
understanding the back-bending phenomena, where the internal structure of the
yrast band changes dramatically as a function of angular momentum. A
microscopic framework to obtain the diabatic bands within the mean-field
approximation is presented by making use of the selfconsistent collective
coordinate method. Applying the framework, both the ground state rotational
bands and the Stockholm bands are studied systematically for the rare-earth
deformed nuclei. An overall agreement has been achieved between the calculated
and observed rotational spectra. It is also shown that the inclusion of the
double-stretched quadrupole-pairing interaction is crucial to obtain an overall
agreement for the even-odd mass differences and the rotational spectra
simultaneously.

</DOC>
<DOC>
<DOCNO> 150529 </DOCNO>
Casimir Energy and Thermodynamic Properties of the Relativistic


  The Casimir energy for the transverse oscillations of a piecewise uniform
closed string is calculated. The great adaptibility of this string model with
respect to various regularization methods is pointed out. We survey several
regularization methods: the cutoff method, the complex contour integration
method, and the zeta-function method. The most powerful method in the present
case is the contour integration method. The Casimir energy turns out to be
negative, and more so the larger is the number of pieces in the string. The
thermodynamic free energy F is calculated for a two-piece string in the limit
when the tension ratio x=T_{I}/T_{II} approaches zero.

</DOC>
<DOC>
<DOCNO> 10139 </DOCNO>
Efficient Monte Carlo algorithm and high-precision results for


  We present a new Monte Carlo algorithm for studying site or bond percolation
on any lattice. The algorithm allows us to calculate quantities such as the
cluster size distribution or spanning probability over the entire range of site
or bond occupation probabilities from zero to one in a single run which takes
an amount of time scaling linearly with the number of sites on the lattice. We
use our algorithm to determine that the percolation transition occurs at
occupation probability 0.59274621(13) for site percolation on the square
lattice and to provide clear numerical confirmation of the conjectured
4/3-power stretched-exponential tails in the spanning probability functions.

</DOC>
<DOC>
<DOCNO> 170012 </DOCNO>
Macroscopic Interference Effects in Resonant Cavities


  We investigate the possibility of interference effects induced by macroscopic
quantum-mechanical superpositions of almost othogonal coherent states - a
Schroedinger cats state - in a resonant microcavity. Despite the fact that a
single atom, used as a probe of the cat state, on the average only change the
mean number of photons by one unit, we show that this single atom can change
the system drastically. Interference between the initial and almost orthogonal
macroscopic quantum states of the radiation field can now take place.
Dissipation under current experimental conditions is taken into account and it
is found that this does not necessarily change the intereference effects
dramatically.

</DOC>
<DOC>
<DOCNO> 70367 </DOCNO>
Gravitational Wave Astronomy: in Anticipation of First Sources to be


  The first generation of long-baseline laser interferometric detectors of
gravitational waves will start collecting data in 2001-2003. We carefully
analyse their planned performance and compare it with the expected strengths of
astrophysical sources. The scientific importance of the anticipated discovery
of various gravitatinal wave signals and the reliability of theoretical
predictions are taken into account in our analysis. We try to be conservative
both in evaluating the theoretical uncertainties about a source and the
prospects of its detection. After having considered many possible sources, we
place our emphasis on (1) inspiraling binaries consisting of stellar mass black
holes and (2) relic gravitational waves. We draw the conclusion that
inspiraling binary black holes are likely to be detected first by the initial
ground-based interferometers. We estimate that the initial interferometers will
see 2-3 events per year from black hole binaries with component masses
10-15M_\odot, with a signal-to-noise ratio of around 2-3, in each of a network
of detectors consisting of GEO, VIRGO and the two LIGOs. It appears that other
possible sources, including coalescing neutron stars, are unlikely to be
detected by the initial instruments. We also argue that relic gravitational
waves may be discovered by the space-based interferometers in the frequency
interval 2x10^{-3}-10^{-2} Hz, at the signal-to-noise ratio level around 3.

</DOC>
<DOC>
<DOCNO> 152634 </DOCNO>
A Bestiary of Higher Dimensional Taub-NUT-AdS Spacetimes


  We present a menagerie of solutions to the vacuum Einstein equations in six,
eight and ten dimensions. These solutions describe spacetimes which are either
locally asymptotically adS or locally asymptotically flat, and which have
non-trivial topology. We discuss the global structure of these solutions, and
their relevance within the context of M-theory.

</DOC>
<DOC>
<DOCNO> 123213 </DOCNO>
Advanced methods for cosmic microwave background data analysis: the big


  In this talk I propose the first fast methods which can analyze CMB data
taking into account correlated noise, arbitrary beam shapes, non-uniform
distribution of integration time on the sky, and partial sky coverage, without
the need for approximations. These ring torus methods work by performing the
analysis in the time ordered domain (TOD) rather than on the sky map of
fluctuations. They take advantage of the simplicity of noise correlations in
the TOD as well as certain properties of the group of rotations SO(3). These
properties single out a family of scanning strategies as favorable, namely
those which scan on rings and have the geometry of an n-torus. This family
includes the strategies due to TOPHAT, MAP and Planck. I first develop the
tools to model the time ordered signal, using Fast Fourier Transform methods
for convolution of two arbitrary functions on the sphere (Wandelt and G\'orski
2000). Then I apply these ideas to show that in the case of a 2-torus one can
reduce the time taken for CMB power spectrum analysis from an unfeasible order
N^3 to order N^2, where N ~ 10^5-10^8 is the number of resolution elements
(Wandelt and Hansen, in preparation).

</DOC>
<DOC>
<DOCNO> 10557 </DOCNO>
Lifetime Effects in Color Superconductivity at Weak Coupling


  Present computations of the gap of color superconductivity in weak coupling
assume that the quarks which participate in the condensation process are
infinitely long-lived. However, the quasiparticles in a plasma are
characterized by having a finite lifetime. In this article we take into account
this fact to evaluate its effect in the computation of the color gap. By first
considering the Schwinger-Dyson equations in weak coupling, when one-loop
self-energy corrections are included, a general gap equation is written in
terms of the spectral densities of the quasiparticles. To evaluate lifetime
effects, we then model the spectral density by a Lorentzian function. We argue
that the decay of the quasiparticles limits their efficiency to condense. The
value of the gap at the Fermi surface is then reduced. To leading order, these
lifetime effects can be taken into account by replacing the coupling constant
of the gap equation by a reduced effective one.

</DOC>
<DOC>
<DOCNO> 71513 </DOCNO>
Phenomenology of Supersymmetric Theories with and without R-Parity


  We review supersymmetry models with and without R-parity. After briefly
describing the Minimal Supersymetric Standard Model and its particle content we
move to models where R-parity is broken, either spontaneously or explicitly. In
this last case we consider the situation where R-parity is broken via bilinear
terms in the superpotential. The radiative breaking of these models is
described in the context of $b$--$\tau$ and $b$--$\tau$--$t$ unification.
Finally we review the phenomenology of these R-parity violating models.

</DOC>
<DOC>
<DOCNO> 70330 </DOCNO>
The see-saw mechanism and heavy Majorana neutrino masses in an SO(10)


  We apply the see-saw mechanism and an SO(10) model to neutrino masses and
mixing in order to estimate the heavy Majorana masses. We discuss shortly the
decay modes of heavy Majorana neutrinos and calculate their contribution to the
lepton number violating processes \mu\to e\gamma, \tau\to\mu\gamma and \tau\to
e\gamma.

</DOC>
<DOC>
<DOCNO> 99535 </DOCNO>
The Digit Principle


  A number of constructions in function field arithmetic involve extensions
from linear objects using digit expansions. This technique is described here as
a method of constructing orthonormal bases in spaces of continuous functions.
We illustrate several examples of orthonormal bases from this viewpoint, and we
also obtain a concrete model for the continuous functions on the integers of a
local field as a quotient of a Tate algebra in countably many variables.

</DOC>
<DOC>
<DOCNO> 85475 </DOCNO>
Teleparallel Gravity: An Overview


  The fundamentals of the teleparallel equivalent of general relativity are
presented, and its main properties described. In particular, the field
equations, the definition of an energy--momentum density for the gravitational
field, the teleparallel version of the equivalence principle, and the dynamical
role played by torsion as compared to the corresponding role played by
curvature in general relativity, are discussed in some details.

</DOC>
<DOC>
<DOCNO> 170215 </DOCNO>
Reconstruction of SU(1,1) States


  We show how group symmetries can be used to reconstruct quantum states. In
our scheme for SU(1,1) states, the input field passes through a non-degenerate
parametric amplifier and one measures the probability of finding the output
state with a certain number (usually zero) of photons in each mode. The density
matrix in the Fock basis is retrieved from the measured data by least squares
method after singular value decomposition of the design matrix. Several
illustrative examples involving the reconstruction of a pair coherent state, a
Perelomov coherent state, and a coherent superposition of pair coherent states
are considered.

</DOC>
<DOC>
<DOCNO> 80589 </DOCNO>
A proposal for analyzing the classical limit of kinematic loop gravity


  We analyze the classical limit of kinematic loop quantum gravity in which the
diffeomorphism and hamiltonian constraints are ignored. We show that there are
no quantum states in which the primary variables of the loop approach, namely
the SU(2) holonomies along {\em all} possible loops, approximate their
classical counterparts. At most a countable number of loops must be specified.
To preserve spatial covariance, we choose this set of loops to be based on
physical lattices specified by the quasi-classical states themselves. We
construct ``macroscopic'' operators based on such lattices and propose that
these operators be used to analyze the classical limit. Thus, our aim is to
approximate classical data using states in which appropriate macroscopic
operators have low quantum fluctuations.
  Although, in principle, the holonomies of `large' loops on these lattices
could be used to analyze the classical limit, we argue that it may be simpler
to base the analysis on an alternate set of ``flux'' based operators. We
explicitly construct candidate quasi-classical states in 2 spatial dimensions
and indicate how these constructions may generalize to 3d. We discuss the less
robust aspects of our proposal with a view towards possible modifications.
Finally, we show that our proposal also applies to the diffeomorphism invariant
Rovelli model which couples a matter reference system to the Hussain Kucha{\v
r} model.

</DOC>
<DOC>
<DOCNO> 152248 </DOCNO>
The action of N=4 Super Yang-Mills from a chiral primary operator


  Using the Vafa-Witten twisted version of N=4 Super Yang-Mills a subset of the
supercharges actually relevant for the nonrenormalization properties of the
theory is identified. In particular, a relationship between the gauge-fixed
action and the chiral primary operator tr(\phi)^2 is worked out. This result
can be understood as an off-shell extension of the reduction formula introduced
by Intriligator.

</DOC>
<DOC>
<DOCNO> 99390 </DOCNO>
Manifolds with boundary and of bounded geometry


  For non-compact manifolds with boundary we prove that bounded geometry
defined by coordinate-free curvature bounds is equivalent to bounded geometry
defined using bounds on the metric tensor in geodesic coordinates.
  We produce a nice atlas with subordinate partition of unity on manifolds with
boundary of bounded geometry, and we study the change of geodesic coordinate
maps.

</DOC>
<DOC>
<DOCNO> 83190 </DOCNO>
Design and Evaluation of Mechanisms for a Multicomputer Object Store


  Multicomputers have traditionally been viewed as powerful compute engines.
It is from this perspective that they have been applied to various problems in
order to achieve significant performance gains. There are many applications for
which this compute intensive approach is only a partial solution. CAD, virtual
reality, simulation, document management and analysis all require timely access
to large amounts of data. This thesis investigates the use of the object store
paradigm to harness the large distributed memories found on multicomputers. The
design, implementation, and evaluation of a distributed object server on the
Fujitsu AP1000 is described. The performance of the distributed object server
under example applications, mainly physical simulation problems, is used to
evaluate solutions to the problems of client space recovery, object migration,
and coherence maintenance.
  The distributed object server follows the client-server model, allows object
replication, and uses binary semaphores as a concurrency control measure.
Instrumentation of the server under these applications supports several
conclusions: client space recovery should be dynamically controlled by the
application, predictively prefetching object replicas yields benefits in
restricted circumstances, object migration by storage unit (segment) is not
generally suitable where there are many objects per storage unit, and binary
semaphores are an expensive concurrency control measure in this environment.

</DOC>
<DOC>
<DOCNO> 170014 </DOCNO>
The Global Nature of the Arrow of Time and the Bohm-Reichenbach diagram


  The importance of the global nature of the arrow of time is shown. Classical
Reichenbach diagram and quantum Bohm-Reichenbach diagram, for the universe are
introduced. They are used to show the increase of entropy in closed systems,
the global nature of the quantum measurement, and the relation among the
different arrows of time.

</DOC>
<DOC>
<DOCNO> 70542 </DOCNO>
KMS conditions for 4-point Green functions at finite temperature


  We study the 4-point function in the Keldysh formalism of the closed time
path formulation of real time finite temperature field theory.
 We derive the KMS conditions for these functions and discuss the number of
4-point functions that are independent. We define a set of `physical' functions
which are linear combinations of the usual Keldysh functions. We show that
these functions satisfy simple KMS conditions. In addition, we consider a set
of integral equations which represent a resummation of ladder graphs. We show
that these integral equations decouple when one uses the physical functions
that we have defined. We discuss the generalization of these results to QED.

</DOC>
<DOC>
<DOCNO> 101301 </DOCNO>
Modular invariants and subfactors


  In this lecture we explain the intimate relationship between modular
invariants in conformal field theory and braided subfactors in operator
algebras. Our analysis is based on an approach to modular invariants using
braided sector induction ("$\alpha$-induction") arising from the treatment of
conformal field theory in the Doplicher-Haag-Roberts framework. Many properties
of modular invariants which have so far been noticed empirically and considered
mysterious can be rigorously derived in a very general setting in the subfactor
context. For example, the connection between modular invariants and graphs (cf.
the A-D-E classification for $SU(2)_k$) finds a natural explanation and
interpretation. We try to give an overview on the current state of affairs
concerning the expected equivalence between the classifications of braided
subfactors and modular invariant two-dimensional conformal field theories.

</DOC>
<DOC>
<DOCNO> 170101 </DOCNO>
On the tritium $\beta$- electrons energy shape


  A series of high presicion atomic experiments was carried out last decade to
get a better estimate for the electron (anti)neutrino mass $m_\nu$. The
reaction to be observed is molecular tritium $\beta$- decay. The $m_\nu$ value
serves as one of the tune parameters to fit $\beta$- electrons spectrum via
reference theoretical one. The unexpected message consists of that parameter
${m^2_\nu}$ has to be fixed at some negative value to get best statistically
reliable fit. Apart of some exotic scenarios suggested the problem remains
open. In this paper we tried to reanalyze ground features of the final states
spectrum (FSS) and its influence on the $\beta$- electrons spectrum. A new
approach has been developed which gives some hints to make proper modifications
to the tabulated FSS in the course of experimental fits.

</DOC>
<DOC>
<DOCNO> 71789 </DOCNO>
Are High Energy Heavy Ion Collisions similar to a Little Bang, or just a


  The talk is a brief overview of what we recently learned about excited
hadronic matter from heavy ion collisions. The central issue is that the
systems produced do exhibit macroscopic behavior, it flows and we start getting
some idea about its effective Equation of State (EoS). More specifically, we
concentrate on elliptic flow, from SPS to RHIC energies, as well as on particle
composition and fluctuations. Note that a pressure and the rate of fluctuation
relaxation (discussed at the end) are ultimately a measure of a collision rate
in the system we would like to understand.

</DOC>
<DOC>
<DOCNO> 121983 </DOCNO>
Ground-state OH observations towards NGC 6334


  We have made observations of the four hyperfine transitions of the 2Pi(3/2),
J=3/2 ground state of OH at 1612, 1665, 1667 and 1720 MHz and the related
1.6-GHz continuum emission, towards NGC 6334 using the Australia Telescope
Compact Array. The observations covered all the major radio continuum
concentrations aligned along the axis of NGC 6334 (V, A to F). We have detected
seven OH masers plus a possible faint eighth maser; two of these masers are
located towards NGC 6334-A. Absorption at 1665 and 1667 MHz was detected
towards almost all the continuum distribution. All transitions showed non-LTE
behaviour. The 1667-/1665-MHz intensity ratios ranged from 1.0 to 1.2,
significantly less than their LTE value of 1.8. The results of the OH `Sum
Rule' suggest that this discrepancy cannot be explained solely by high optical
depths. The 1612- and 1720-MHz line-profiles showed conjugate behaviour whereby
one line was in absorption and the other in emission. In addition, the profiles
commonly showed a flip from absorption to emission and vice versa, which has
been interpreted as a density gradient. The OH line-to-continuum distribution,
optical depth and velocity trends are consistent with a bar-like shape for the
molecular gas which wraps around the continuum emission.

</DOC>
<DOC>
<DOCNO> 9667 </DOCNO>
Transport mean free path for Magneto-Transverse Light Diffusion: an


  This article presents a derivation of the transport mean free path for
magneto-transverse light diffusion, $\ell^*_\perp$, in an arbitrary random
mixture of Faraday-active and non-Faraday active Mie scatterers. This
derivation is based on the standard radiative transfer equation. The expression
of the transport mean free path obtained previously from the Bethe-Salpether
equation, for the case where only Faraday-active scatterers are present,is
recovered. This simpler formulation can include the case of homogeneous
mixtures of Faraday-active and non-Faraday active scatterers.

</DOC>
<DOC>
<DOCNO> 40219 </DOCNO>
Does the KARMEN time anomaly originate from a beam-correlated


  The time anomaly of neutrino events observed in the KARMEN detector at the
ISIS facility is discussed. We show that beam-correlated neutron events are not
completely suppressed by the KARMEN lower energy cut and could cause the
observed deviation of the measured time distribution from an exponential curve
with tau = 2.2 microseconds.

</DOC>
<DOC>
<DOCNO> 68212 </DOCNO>
Radiative magnification of neutrino mixings and a natural explanation of


  We show that the neutrino mixing pattern with the large mixing required for
the atmospheric neutrino problem and the small mixing angle MSW solution for
the solar neutrino problem can be naturally generated through radiative
magnification, even though all the mixing angles at the seesaw scale may be
small. This can account for the neutrino anomalies as well as the CHOOZ
constraints in the context of quark-lepton unified theories, where the quark
and lepton mixing angles are expected to be similar in magnitude at the high
scale. We also indicate the 4$\nu$ mixing scenarios for which this mechanism of
radiative magnification can provide a natural explanation.

</DOC>
<DOC>
<DOCNO> 120734 </DOCNO>
Supernova Remnants in the Sedov Expansion Phase: Thermal X-Ray Emission


  Improved calculations of X-ray spectra for supernova remnants (SNRs) in the
Sedov-Taylor phase are reported, which for the first time include reliable
atomic data for Fe L-shell lines. This new set of Sedov models also allows for
a partial collisionless heating of electrons at the blast wave and for energy
transfer from ions to electrons through Coulomb collisions. X-ray emission
calculations are based on the updated Hamilton-Sarazin spectral model. The
calculated X-ray spectra are succesfully interpreted in terms of three
distribution functions: the electron temperature and ionization timescale
distributions, and the ionization timescale averaged electron temperature
distribution. The comparison of Sedov models with a frequently used single
nonequilibrium ionization (NEI) timescale model reveals that this simple model
is generally not an appropriate approximation to X-ray spectra of SNRs. We find
instead that plane-parallel shocks provide a useful approximation to X-ray
spectra of SNRs, particularly for young SNRs. Sedov X-ray models described
here, together with simpler plane shock and single ionization timescale models,
have been implemented as standard models in the widely used XSPEC v11 spectral
software package.

</DOC>
<DOC>
<DOCNO> 116414 </DOCNO>
Diffraction as a Consequence of Faraday's Law


  We consider a linearly polarized electromagnetic wave incident on an opaque
screen with square aperture of edge a. An application of Faraday's law to a
loop parallel to the screen, on the side away from the source, shows that the
wave must have longitudinal components there. The ratio of the longitudinal to
transverse field is a measure of the diffraction angle.

</DOC>
<DOC>
<DOCNO> 85061 </DOCNO>
Gravitational waves from extreme mass ratio inspirals: Challenges in


  In its final year of inspiral, a stellar mass ($1 - 10 M_\odot$) body orbits
a massive ($10^5 - 10^7 M_\odot$) compact object about $10^5$ times, spiralling
from several Schwarzschild radii to the last stable orbit. These orbits are
deep in the massive object's strong field, so the gravitational waves that they
produce probe the strong field nature of the object's spacetime. Measuring
these waves can, in principle, be used to ``map'' this spacetime, allowing
observers to test whether the object is a black hole or something more exotic.
Such measurements will require a good theoretical understanding of wave
generation during inspiral. In this article, I discuss the major theoretical
challenges standing in the way of building such maps from gravitational-wave
observations, as well as recent progress in producing extreme mass ratio
inspirals and waveforms.

</DOC>
<DOC>
<DOCNO> 152532 </DOCNO>
Instabilities in heterotic M-theory induced by open membrane instantons


  We study the effective low energy supergravity of the strongly coupled
heterotic string compactified on a Calabi-Yau 3-fold with generic E8 x E8 gauge
bundle. We focus on the effective potential for the chiral scalars. The
effective superpotential can be studied using the dual 11-dimensional M-theory
background involving insertions of M5 branes along an interval. In such
backgrounds, in some regions of moduli space, the leading nonperturbative
contributions are due to open membrane instantons. These instantons lead to
both attractive and repulsive forces between the 5-branes and the orientifold
``M9-branes,'' depending on the region of moduli space. The resulting dynamics
on moduli space include a strong coupling dual to the Dine-Seiberg instability,
in which the interval grows. We discuss conditions under which the 5-branes are
attracted to the wall and comment on the relevance of these results to the
study of chirality-changing phase transitions in heterotic M-theory.

</DOC>
<DOC>
<DOCNO> 121591 </DOCNO>
Photon Consumption in Minihalos during Cosmological Reionization


  At the earliest epochs of structure formation in cold dark matter (CDM)
cosmologies, the smallest nonlinear objects are the numerous small halos that
condense with virial temperatures below 10,000 K. Such ``minihalos'' are not
yet resolved in large-scale three-dimensional cosmological simulations. Here we
employ a semi-analytic method, combined with three-dimensional simulations of
individual minihalos, to examine their importance during cosmological
reionization. We show that, depending on when reionization takes place, they
potentially play an important role as sinks of ionizing radiation. If
reionization occurs at sufficiently high redshifts (z_r > 20), the
intergalactic medium is heated to 10,000 K and most minihalos never form. On
the other hand, if z_r < 20, a significant fraction (>10 percent) of all
baryons have already collapsed into minihalos, and are subsequently removed
from the halos by photoevaporation as the ionizing background flux builds up.
We show that this process can require a significant budget of ionizing photons;
exceeding the production by a straightforward extrapolation back in time of
known quasar and galaxy populations by a factor of up to 10 and 3,
respectively.

</DOC>
<DOC>
<DOCNO> 70280 </DOCNO>
A variational study of bound states in the Higgs model


  The possible existence of Higgs-Higgs bound states in the Higgs sector of the
Standard Model is explored using the |hh>+|hhh> variational ansatz of Di Leo
and Darewych. The resulting integral equations can be decoupled exactly,
yielding a one-dimensional integral equation, solved numerically. We thereby
avoid the extra approximations employed by Di Leo and Darewych, and we find a
qualitatively different mass renormalization. Within the conventional scenario,
where a not-too-large cutoff is invoked to avoid "triviality", we find, as
usual, an upperbound on the Higgs mass. Bound-state solutions are only found in
the very strong coupling regime, but at the same time a relatively small
physical mass is required as a consequence of renormalization.

</DOC>
<DOC>
<DOCNO> 68047 </DOCNO>
Hadronic Light-Cone Wavefunctions and the Unification of QCD Bound-State


  The light-cone Fock representation encodes the bound-state quark and gluon
properties of hadrons, including their helicity and flavor correlations, in
terms of universal process-independent and frame-independent wavefunctions. It
also provides a physical factorization scheme for separating hard and soft
contributions in both exclusive and inclusive hard processes. A new type of jet
production reaction, ''self-resolving diffractive interactions'' can provide
direct information on the light-cone wavefunctions of hadrons in terms of their
QCD degrees of freedom as well as the composition of nuclei in terms of their
nucleon and mesonic degrees of freedom.

</DOC>
<DOC>
<DOCNO> 40446 </DOCNO>
Light meson and baryon spectroscopy from charm decays in Fermilab E791


  We present results from Fermilab experiment E791. We extracted the fractions
of resonant components in the $\Lambda_c^+\to p K^- \pi^+$ decays, and found a
significant polarization of the $\Lambda_c^+$ using a fully 5-dimensional
resonant analysis. We also did resonant analyses of $D^+$ and $D^+_s$ decays
into $\pi^+\pi^-\pi^+$. We observed an insignificant asymmetry in the Breit
Wigner describing the $f_0(980)$ and found good evidence for a light and broad
scalar resonance in the $D^+$ decays.

</DOC>
<DOC>
<DOCNO> 152166 </DOCNO>
Nonanalyticity of the beta-function and systematic errors in


  We consider the fixed-dimension perturbative expansion. We discuss the
nonanalyticity of the renormalization-group functions at the fixed point and
its consequences for the numerical determination of critical quantities.

</DOC>
<DOC>
<DOCNO> 123243 </DOCNO>
Early dust evolution in protostellar accretion disks


  We investigate dust dynamics and evolution during the formation of a
protostellar accretion disk around intermediate mass stars via 2D numerical
simulations. Using three different detailed dust models, compact spherical
particles, fractal BPCA grains, and BCCA grains, we find that even during the
early collapse and the first 10,000 yr of dynamical disk evolution, the initial
dust size distribution is strongly modified. Close to the disk's midplane
coagulation produces dust particles of sizes of several 10 micons (for compact
spherical grains) up to several mm (for fluffy BCCA grains), whereas in the
vicinity of the accretion shock front (located several density scale heights
above the disk), large velocity differences inhibit coagulation. Dust particles
larger than about 1 micron segregate from the smaller grains behind the
accretion shock. Due to the combined effects of coagulation and grain
segregation the infrared dust emission is modified. Throughout the accretion
disk a MRN dust distribution provides a poor description of the general dust
properties. Estimates of the consequences of the "freezing out" of molecules in
protostellar disks should consider strongly modified grains. Physical model
parameters such as the limiting sticking strength and the grains' resistivity
against shattering are crucial factors determining the degree of coagulation
reached. In dense regions (e.g. in the mid-plane of the disk) a steady-state is
quickly attained. High above the equatorial plane coagulation equilibrium is
not reached due to the much lower densities. Here, the dust size distribution
is affected primarily by differential advection, rather than coagulation.

</DOC>
<DOC>
<DOCNO> 70871 </DOCNO>
Nonequilibrium Fields: Exact and Truncated Dynamics


  The nonperturbative real-time evolution of quantum fields out of equilibrium
is often solved using a mean-field or Hartree approximation or by applying
effective action methods. In order to investigate the validity of these
truncations, we implement similar methods in classical scalar field theory and
compare the approximate dynamics with the full nonlinear evolution. Numerical
results are shown for the early-time behaviour, the role of approximate fixed
points, and thermalization.

</DOC>
<DOC>
<DOCNO> 118342 </DOCNO>
Systematic effects in the interpretations of Cluster X-ray Temperature


  The formation and evolution of clusters of galaxies are sensitive to the
underlying cosmological model. Constraints on cosmological parameters of cold
dark matter models have been derived from mass, temperature and luminosity
functions of clusters. We study the importance of including cluster formation
history and a correction for collapsed fraction of objects in determining the
cluster X-ray temperature function. We find that both effects are important. We
compare temperature functions obtained by using a power law approximation for
the mass variance normalized to X-ray clusters to those obtained by using a
COBE normalized full CDM treatment. We conclude that the temperature function
could be a powerful test on the average density of the Universe if we could
find the correct way of interpreting the data.

</DOC>
<DOC>
<DOCNO> 116935 </DOCNO>
A High-Intensity H- Linac at CERN Based on LEP-2 Cavities


  In view of a possible evolution of the CERN accelerator complex towards
higher proton intensities, a 2.2 GeV H- linac with 4 MW beam power has been
designed, for use in connection with an accumulator and compressor ring as
proton driver of a muon-based Neutrino Factory. The high-energy part of this
linac can use most of the RF equipment (superconducting cavities and klystrons)
from the LEP collider after its decommissioning at the end of 2000. Recent
results concerning low-beta superconducting cavities are presented, and the
main characteristics of the linac design are described. The complete
linac-based proton driver facility is outlined, and the impact on the linac
design of the requirements specific to a Neutrino Factory is underlined.

</DOC>
<DOC>
<DOCNO> 120395 </DOCNO>
Resolved Spectra of the Narrow-Line Region in NGC 1068. III. Physical


  The physical conditions in the inner narrow line region (NLR) of the Seyfert
2 galaxy NGC 1068 are examined using HST/STIS ultraviolet and optical spectra
and photoionization models. 1) The emission-line gas in the blueshifted
northeast quadrant is photoionized by the hidden central source out to 100 pc,
at which point we find evidence of another source of ionizing radiation, which
may be due to fast (1000 km/s) shocks resulting from the interaction of the
emission-line knots and the interstellar medium. 2) The gas in the redshifted
northeast quadrant is photoionized by continuum radiation that has been heavily
absorbed by gas within 30 pc of the central source. We find no strong evidence
of the effects of shocks in this component. 3) The redshifted emission-line gas
in the southwest quadrant is photoionized by unabsorbed continuum from the
central source, similar to that in the inner 100 pc of the blueshifted
northeast quadrant. Finally, 4) the emission-line spectrum of the blueshifted
southwest quadrant appears to be the superposition of highly ionized, tenuous
component within the ionization cone and gas outside the cone, the latter
photoionized by scattered continuum radiation. There are several implications
of this complicated physical scenario. First, the hidden active nucleus is the
dominant source of ionizing radiation in the inner NLR. The absorption of
continuum radiation along the line-of-sight to the redshifted northeast
quadrant may result from the intersection of the ionization cone and the plane
of the host galaxy. Finally, the evidence for shock-induced continuum radiation
at the point where the emission-line knots begin to decelerate indicates that
the deceleration is due to the interaction of emission-line knots with slower
moving gas.

</DOC>
<DOC>
<DOCNO> 120809 </DOCNO>
A search for clusters at high redshift - II. A proto cluster around a


  VLT spectroscopic observations of Ly alpha--excess objects in the field of
the clumpy radio galaxy 1138-262 at z=2.16 have led to the discovery of 14
galaxies and one QSO at approximately the same distance as the radio galaxy.
All galaxies have redshifts in the range 2.16 \pm 0.02, centered around the
redshift of the radio galaxy, and are within a projected physical distance of
1.5 Mpc from it. The velocity distribution suggests that there are two galaxy
subgroups having velocity dispersions of ~500 km/s and ~300 km/s and a relative
velocity of 1800 km/s. If these are virialized structures, the estimated
dynamical masses for the subgroups are ~9 and ~3x10E13 solar masses
respectively, implying a total mass for the structure of more than 10E14 solar
masses. The new observations, together with previous results, suggest that the
structure of galaxies around 1138-262 is likely to be a forming cluster.

</DOC>
<DOC>
<DOCNO> 117828 </DOCNO>
Steady dynamos in finite domains: an integral equation approach


  The paper deals with the integral equation approach to steady kinematic
dynamo models in finite domains based on Biot-Savart's law. The role of the
electric potential at the boundary is worked out explicitly. As an example, a
modified version of the simple spherical $\alpha$-effect dynamo model proposed
by Krause and Steenbeck is considered in which the $\alpha$-coefficient is no
longer constant but may vary with the radial coordinate. In particular, the
results for the original model are re-derived. Possible applications of this
integral equation approach for numerical simulations of dynamos in arbitrary
geometry and for an ''inverse dynamo theory'' are sketched.

</DOC>
<DOC>
<DOCNO> 7850 </DOCNO>
Effective Low Energy Theories and QCD Dirac Spectra


  We analyze the smallest Dirac eigenvalues by formulating an effective theory
for the QCD Dirac spectrum. We find that in a domain where the kinetic term of
the effective theory can be ignored, the Dirac eigenvalues are distributed
according to a Random Matrix Theory with the global symmetries of the QCD
partition function. The kinetic term provides information on the slope of the
average spectral density of the Dirac operator. In the second half of this
lecture we interpret quenched QCD Dirac spectra at nonzero chemical potential
(with eigenvalues scattered in the complex plane) in terms of an effective low
energy theory.

</DOC>
<DOC>
<DOCNO> 151743 </DOCNO>
Superstrings and Topological Strings at Large N


  We embed the large N Chern-Simons/topological string duality in ordinary
superstrings. This corresponds to a large $N$ duality between generalized gauge
systems with N=1 supersymmetry in 4 dimensions and superstrings propagating on
non-compact Calabi-Yau manifolds with certain fluxes turned on. We also show
that in a particular limit of the N=1 gauge theory system, certain
superpotential terms in the N=1 system (including deformations if spacetime is
non-commutative) are captured to all orders in 1/N by the amplitudes of
non-critical bosonic strings propagating on a circle with self-dual radius. We
also consider D-brane/anti-D-brane system wrapped over vanishing cycles of
compact Calabi-Yau manifolds and argue that at large $N$ they induce a shift in
the background to a topologically distinct Calabi-Yau, which we identify as the
ground state system of the Brane/anti-Brane system.

</DOC>
<DOC>
<DOCNO> 121513 </DOCNO>
Maximum Galactic Disks vs. Hot Dark Halos


  A series of arguments is presented for heavy galaxy disks not only in the
optical regions, but also in the dark matter dominated regions of spirals. We
are testing this possibility with extreme maximum disk N-body models without
any conventional spheroidal dark halo.

</DOC>
<DOC>
<DOCNO> 119421 </DOCNO>
Hubble Space Telescope Imaging of Bipolar Nuclear Shells in the


  We present broadband and narrowband Hubble Space Telescope images of the
central region of the heavily disturbed Virgo cluster galaxy NGC 4438 (Arp120),
whose nucleus has been described as a type 1 LINER or dwarf Seyfert. Narrowband
H-alpha and [NII] HST images reveal striking bipolar shell features, 1 kpc in
projected length from end-to-end, which are likely the result of an outflow
from the nuclear region experiencing a strong interaction with the ISM. While
these outflow shells share similarities with those in some other starburst or
AGN galaxies, these in NGC 4438 are notable because NGC 4438 harbors neither a
luminous circumnuclear starburst nor a luminous AGN. The shells appear to be
closed at their outer ends, suggesting that the outflow in NGC 4438 is
dynamically younger than those in some other galaxies. The radio continuum
emission is strongly enhanced near the outer ends of the shells, suggesting
working surfaces arising from collimated nuclear outflows which have impacted
and shocked the surrounding ISM. The 2 shells are quite different, as the
northwestern (NW) shell is luminous and compact, while the southeastern (SE)
shell is 2.5 times longer and much fainter, in both optical emission lines and
the non-thermal radio continuum. The differences between the 2 shells may be
attributed to a difference in ISM density on the 2 sides of the nuclear disk.
Such an ISM asymmetry exists on larger scales in this heavily disturbed galaxy.
At the base of the outflow is a nuclear source, which is the highest surface
brightness source in the galaxy at optical wavelengths, We discuss whether the
outflow is powered by a low luminosity AGN or a compact nuclear starburst.

</DOC>
<DOC>
<DOCNO> 117550 </DOCNO>
Symbiotic Miras can do it


  Symbiotic Miras give a nice practical demonstration of the formation of
bipolar and highly aspherical nebulae as a consequence of interaction in
detached binaries. We believe that these binary systems are among the most
promising candidates for the progenitors of bipolar planetary nebulae. We
present a list of the optically extended nebulae known to date around symbiotic
Miras, and illustrate their properties using recent HST and ESO-NTT [NII]
images of He 2-104 and He 2-147.

</DOC>
<DOC>
<DOCNO> 9224 </DOCNO>
Can half metallic zincblende MnAs be grown?


  In this paper we investigate theoretically the ground state NiAs-type
structure of MnAs and we compare the magnetic and structural properties with an
hypothetical zincblende structure. A zincblende structure can be obtained, in
principle, from the diluted magnetic semiconductor Ga$_{1-x}$Mn$_x$As in the
limit $x=1$. Using density functional calculations within the local
spin-density approximation (LSDA), we show that the zincblende structure,
although showing half metallic behavior which is very attractive for
spintronics, can not be stabilized at equilibrium. We perform a tight-binding
analysis of the Mn-As bond in the tetrahedral coordination to investigate the
nature of the bonding in diluted magnetic semiconductors.

</DOC>
<DOC>
<DOCNO> 10457 </DOCNO>
Stabilizing an Attractive Bose-Einstein Condensate by Driving a Surface


  Bose-Einstein condensates of $^7$Li have been limited in number due to
attractive interatomic interactions. Beyond this number, the condensate
undergoes collective collapse. We study theoretically the effect of driving
low-lying collective modes of the condensate by a weak asymmetric sinusoidally
time-dependent field. We find that driving the radial breathing mode further
destabilizes the condensate, while excitation of the quadrupolar surface mode
causes the condensate to become more stable by imparting quasi-angular momentum
to it. We show that a significantly larger number of atoms may occupy the
condensate, which can then be sustained almost indefinitely. All effects are
predicted to be clearly visible in experiments and efforts are under way for
their experimental realization.

</DOC>
<DOC>
<DOCNO> 9278 </DOCNO>
Collision-assisted Zeeman cooling of neutral atoms


  We propose a new method to cool gaseous samples of neutral atoms. The gas is
confined in a non dissipative optical trap in the presence of an homogeneous
magnetic field. The method accumulates atoms in the $m_F=0$ Zeeman sub-level.
Cooling occurs via collisions that produce atoms in $m_F\neq 0$ states. Thanks
to the second order Zeeman effect kinetic energy is transformed into internal
energy and recycling of atoms is ensured by optical pumping. This method may
allow quantum degeneracy to be reached by purely optical means.

</DOC>
<DOC>
<DOCNO> 170276 </DOCNO>
Generalization of Grover's Algorithm to Multiobject Search in Quantum


  There are major advantages in a newer version of Grover's quantum algorithm
utilizing a general unitary transformation in the search of a single object in
a large unsorted database. In this paper, we generalize this algorithm to
multiobject search. We show the techniques to achieve the reduction of the
problem to one on an invariant subspace of dimension just equal to two.

</DOC>
<DOC>
<DOCNO> 116639 </DOCNO>
Mathematical investigation of the Boltzmann collisional operator


  With help of direct calculation, it is revealed that an essential concept in
deriving the Boltzmann collisional operator, the scattering cross section in
the laboratory frame, cannot be well defined. Along this line, it is suggested
that the collisional operator, as well as the entire Boltzmann equation, should
be reconsidered.

</DOC>
<DOC>
<DOCNO> 83102 </DOCNO>
Consistency Management of Normal Logic Program by Top-down Abductive


  This paper presents a method of computing a revision of a function-free
normal logic program. If an added rule is inconsistent with a program, that is,
if it leads to a situation such that no stable model exists for a new program,
then deletion and addition of rules are performed to avoid inconsistency. We
specify a revision by translating a normal logic program into an abductive
logic program with abducibles to represent deletion and addition of rules. To
compute such deletion and addition, we propose an adaptation of our top-down
abductive proof procedure to compute a relevant abducibles to an added rule. We
compute a minimally revised program, by choosing a minimal set of abducibles
among all the sets of abducibles computed by a top-down proof procedure.

</DOC>
<DOC>
<DOCNO> 152083 </DOCNO>
Quantum Parafermions in the SL(2,R)/U(1) WZNW Black Hole Model


  Starting with its classical parafermion algebra, we consider the quantisation
of the SL(2,R)/U(1) WZNW black hole model.

</DOC>
<DOC>
<DOCNO> 68353 </DOCNO>
Space-time structure of a bound nucleon


  Distortions of bound nucleon space-time structure, measured in deep inelastic
scattering off nuclei, are discussed from view-point of a theoretical approach
based on the Bethe-Salpeter formalism. It is shown that modification of the
structure function $F_2^{\rm N}$ results from relative time dependence in Green
functions of bound nucleons. The modification plays fundamental role in
analysis of deep inelastic scattering experiments and allows one to obtain new
information about nucleon structure.

</DOC>
<DOC>
<DOCNO> 71330 </DOCNO>
Massive c(\bar c)g-Production in Diffractive DIS


  We calculate the cross section for q(\bar q)g-production in diffractive DIS
with finite fermion masses and zero momentum transfer. The calculation is done
in the leading log(1/x_p) approximation and is valid for the region of high
diffractive masses (small beta). We apply our cross section formula to
diffractive charm production at HERA: in a Monte-Carlo-Simulation of
diffractive D*+- meson production we include both massive q(\bar q)- and
massive q(\bar q)g-production, and we compare with preliminary H1 results.
After adjusting an infrared cutoff parameter of our model which affects the
overall normalization of the cross section we find reasonable agreement with
the data. In particular, the slope of the beta-distribution can be reproduced.

</DOC>
<DOC>
<DOCNO> 9459 </DOCNO>
Superconducting $d_{x^2-y^2} \pm id_{xy}$ phase glass


  We discuss the effects of magnetic impurities on d-wave superconductors. We
calculate the electron mediated RKKY interaction between the impurity spins in
a d-wave superconductor and find that it decays as $r^{-3}$ at large distances.
We argue that this interaction leads to the formation of a spin glass at low
temperature $T \ll T_c$. It was previously shown that a local complex $\Delta^1
\sim d_{xy}$ order parameter is induced around each impurity spin. We consider
the pair tunneling resulting in the Josephson interaction between different
patches of induced $d_{xy}$ order parameter. Due to the local coupling between
impurity spins and the superconducting order parameter the Josephson coupling
favors a ferromagnetic phase at low temperatures. The competition between the
Josephson coupling and the RKKY interaction gives rise to an interesting phase
diagram. At low impurity concentrations we find an unusual supercondcting phase
glass, where the impurity spins $S^z$ and $d_{xy}$ component are disordered and
yet the product of these two develops a true long range order $<S^z \Delta^1>$.
This phase has no analog in purely magnetic spin glasses and arises as a result
of the direct coupling of the impurity spin to the phase of $\Delta^1$. At high
impurity concentrations it is possible that a ferromagnetic phase will form.

</DOC>
<DOC>
<DOCNO> 101802 </DOCNO>
A direct proof of a theorem of Blaschke and Lebesgue


  The Blaschke-Lebesgue Theorem states that among all planar convex domains of
given constant width B the Reuleaux triangle has minimal area. It is the
purpose of the present note to give a direct proof of this theorem by analyzing
the underlying variational problem. The advantages of the proof are that it
shows uniqueness (modulo rigid deformations such as rotation and translation)
and leads analytically to the shape of the area-minimizing domain. Most
previous proofs have relied on foreknowledge of the minimizing domain. Key
parts of the analysis extend to the higher-dimensional situation, where the
convex body of given constant width and minimal volume is unknown.

</DOC>
<DOC>
<DOCNO> 151624 </DOCNO>
BPS States and Automorphisms


  The purpose of the present paper is twofold. In the first part, we provide an
algebraic characterization of several families of $\nu= \frac{1}{2^n}$ $n\leq
5$ BPS states in M theory, at threshold and non-threshold, by an analysis of
the BPS bound derived from the ${\cal N}=1$ D=11 SuperPoincar\'e algebra. We
determine their BPS masses and their supersymmetry projection conditions,
explicitly. In the second part, we develop an algebraic formulation to study
the way BPS states transform under $GL(32,\bR)$ transformations, the group of
automorphisms of the corresponding SuperPoincar\'e algebra. We prove that all
$\nu={1/2}$ non-threshold bound states are SO(32) related with $\nu={1/2}$ BPS
states at threshold having the same mass. We provide further examples of this
phenomena for less supersymmetric $\nu={1/4},{1/8}$ non-threshold bound states.

</DOC>
<DOC>
<DOCNO> 67922 </DOCNO>
Lambda and Lambda-bar polarization in polarized DIS


  We consider the polarization of Lambda + Lambda-bar baryons produced in
polarized Deep Inelastic Scattering at leading order, with various spin
configurations: longitudinally polarized leptons and unpolarized nucleon;
unpolarized leptons and longitudinally or transversely polarized nucleons;
longitudinally polarized leptons and nucleons. We show how the different
results in the different cases are related to different aspects of the
elementary dynamics and to the spin properties of the distribution and
fragmentation functions and show how a combined analysis might give useful
information. We give numerical results according to several sets of polarized
fragmentation functions recently proposed.

</DOC>
<DOC>
<DOCNO> 119830 </DOCNO>
Optical Spectrum of Main-, Inter- and Off-pulse Emission from Crab


  A dedicated stroboscopic device was used to obtain optical spectra of the
Crab main-pulse and inter-pulse as well as the spectrum of the underlying
nebula when the pulsar is turned off. As the nebular emission is very
inhomogeneous, our ability to effectively subtract the nebular background
signal is crucial.
  No spectral lines intrinsic to the pulsar are detected. The main-pulse and
the inter-pulse behave as power laws, both with the same de-reddened index
Alpha = +0.2 +- 0.1. This value was obtained by subtracting the nebular
spectrum at the exact position of the pulsar. The underlying nebula is redder,
Alpha = -0.4 +- 0.1. Its emission lines are split into approaching (sim. -1200
km/s) and receding (sim. +600 km/s) components. The strength of emission line
components and the flux in nebular continuum vary on arcsec scale. The nebular
line and continuum intensities along the N-S slit are given.

</DOC>
<DOC>
<DOCNO> 121098 </DOCNO>
The survival of subhaloes in galaxies and galaxy clusters


  This paper discusses physical and numerical disruption processes acting on
subhaloes in galaxy haloes and in galaxy cluster haloes, and compare the
effects of these processes on the subhalo abundance within both types of
haloes. N-body simulations with a resolution high enough not to suffer from
overmerging (subhalo disruption due to numerical processes) show a high
abundance of subhaloes in both galaxies and in galaxy clusters. However,
observations seem to show a high subhalo abundance in galaxy clusters only.
Thus, it appears that too many subhaloes survive in simulated galaxy haloes.
There are five main causes for this apparent galaxy subhalo problem. The most
radical one is a change to a cosmology in which structure formation is not
hierarchical below the galaxy halo mass scale. If this is unacceptable, four
causes remain, of which the most important one appears to be that dynamical
friction is not properly simulated yet, not even for the highest resolution
simulations to date, resulting in an 'undermerging' problem. The other causes
are (numerical) overmerging, differences in the timing of halo formation and
merging in hierarchical structure formation, and significant differences is
mass-to-light ratios. The net effect of these four causes is that galaxies have
a relatively low abundance of subhaloes, i.e. dwarfs, while at the same time a
large number of field dwarf galaxies can exist which are dark enough to be
missed observationally.

</DOC>
<DOC>
<DOCNO> 120787 </DOCNO>
The Polar Stellar Ring and Dark Halo of NGC 5907


  Numerical simulations of the disruption of a dwarf companion moving in the
polar plane of a massive galaxy are presented. The constructed model is
compared with observational data on the recently discovered
low-surface-brightness stellar ring around galaxy NGC 5907. Constraints on the
ring lifetime (<=1.5 gyr after the first approach of the galaxies), on the
structure of companion -- the ring presecursor, and on mass of dark halo of the
main galaxy in whose gravitational field the companion moves are provided. The
dark halo mass within 50 kpc of NGC 5907 center cannot exceed 3 or 4 "visible"
masses.

</DOC>
<DOC>
<DOCNO> 8205 </DOCNO>
Asymptotic Energy Decay in Inelastic Fluids


  Replacement of cond-mat/0002383. Re-analysis of computer simulations, new
figures and modification of conclusions.

</DOC>
<DOC>
<DOCNO> 8112 </DOCNO>
A Physical Picture of Superconductivity


  A universal mechanism of superconductivity applicable to ``low temperature''
and ``high temperature'' superconductors is proposed in this paper. With this
model of mechanism experimental facts of superconductors can be qualitatively
explained. A function is introduced to describe the average separation distance
between vibrating lattice atoms, which is crucial for the transition from
normal to superconductive state. However, the most attractive and exciting
conclusion that can be derived from this physical picture, is that given atoms
of other element be successfully sandwiched between ferromagnetic atoms one by
one, a superconductor constructed this way is most likely to have a very high
transition temperature.

</DOC>
<DOC>
<DOCNO> 150342 </DOCNO>
Strings in AdS_3 and the SL(2,R) WZW Model. Part 1: The Spectrum


  In this paper we study the spectrum of bosonic string theory on AdS_3. We
study classical solutions of the SL(2,R) WZW model, including solutions for
long strings with non-zero winding number. We show that the model has a
symmetry relating string configurations with different winding numbers. We then
study the Hilbert space of the WZW model, including all states related by the
above symmetry. This leads to a precise description of long strings. We prove a
no-ghost theorem for all the representations that are involved and discuss the
scattering of the long string.

</DOC>
<DOC>
<DOCNO> 68267 </DOCNO>
Magnetic Moments of Delta Baryons in Light Cone QCD Sum Rules


  We calculate the magnetic moments of Delta baryons within the framework of
QCD sum rules. A comparison of our results on the magnetic moments of the Delta
baryons with the predictions of different approaches is presented.

</DOC>
<DOC>
<DOCNO> 102595 </DOCNO>
Geometric quantization and the generalized Segal-Bargmann transform for


  Let K be a connected Lie group of compact type and let T*(K) be its cotangent
bundle. This paper considers geometric quantization of T*(K), first using the
vertical polarization and then using a natural Kahler polarization obtained by
identifying T*(K) with the complexified group K_C. The first main result is
that the Hilbert space obtained by using the Kahler polarization is naturally
identifiable with the generalized Segal-Bargmann space introduced by the author
from a different point of view, namely that of heat kernels. The second main
result is that the pairing map of geometric quantization coincides with the
generalized Segal-Bargmann transform introduced by the author. This means that
in this case the pairing map is a constant multiple of a unitary map. For both
results it is essential that the half-form correction be included when using
the Kahler polarization. Together with results of the author with B. Driver,
these results may be seen as an instance of "quantization commuting with
reduction."

</DOC>
<DOC>
<DOCNO> 9861 </DOCNO>
Anisotropic penetration depth and optical sum rule violation in


  We calculate the doping dependence of the penetration depths and optical sum
rule violation in La_(2-x)Sr_xCuO_4 within the model of hole superconductivity.
In the clean limit the predicted in-plane sum rule violation is larger than the
c-axis one, however in the presence of disorder the latter one becomes very
substantially enhanced.

</DOC>
<DOC>
<DOCNO> 85220 </DOCNO>
Cosmic strings in axionic-dilatonic gravity


  We first consider local cosmic strings in dilaton-axion gravity and show that
they are singular solutions. Then we take a supermassive Higgs limit and
present expressions for the fields at far distances from the core by applying a
Pecci-Quinn and a duality transformation to the dilatonic Melvin's magnetic
universe.

</DOC>
<DOC>
<DOCNO> 101494 </DOCNO>
Complex Structures on some Stiefel Manifolds


  We discuss conditions for the integrability of an almost complex structure
defined on the total space of an induced Hopf S^3-bundle over a Sasakian
manifold . As an application, we obtain an uncountable family of inequivalent
complex structures on the Stiefel manifolds of orthonormal 2-frames in C^{n+1},
non compatible with its standard hypercomplex structure. Similar families of
complex structures are constructed on the Stiefel manifold of oriented
orthonormal 4-frames in R^{n+1}, as well as on some special Stiefel manifolds
related to the groups G_2 and Spin(7).

</DOC>
<DOC>
<DOCNO> 84588 </DOCNO>
Causal relation between regions I and IV of the Kruskal extension


  By extending the exterior Schwarzschild spacetime in two opposite directions
with the Kruskal method, we get an extension which has the same T-X spacetime
diagram as has the conventional Kruskal extension, while allowing its regions I
and IV to correspond to different directions of the original spacetime. We
further extend the exterior Schwarzschild spacetime in all directions and get a
4-dimensional form of the Kruskal extension. The new form of extension includes
the conventional one as a part of itself. From the point of view of the
4-dimensional form, region IV of the conventional extension does not belong to
another universe but is a portion of the same exterior Schwarzschild spacetime
that contains region I. The two regions are causally related: particles can
move from one to the other.

</DOC>
<DOC>
<DOCNO> 10543 </DOCNO>
Tight Binding Molecular Dynamics Studies of Boron Assisted Nanotube


  In this paper we report a theoretical study of the effects of the presence of
boron in growing carbon nanotubes. We employ a well established Tight Binding
model to describe the interactions responsible for the energetics of these
systems, combined with the Molecular Dynamics simulation technique and
Structural Relaxation calculations. We find, in agreement with the previous
theoretical/experimental work of Blase {\em et al.} [{\em Phys. Rev. Lett.}
{\bf 83}, 5078 (1999)], that boron favors (n,0) (zig-zag) tubular structures
over (n,n) (arm-chair) ones by stabilizing the zig-zag edge. Furthermore, it is
shown that boron has the effect of delaying the tube closure process, a fact
which could explain the improved aspect ratio experimentally observed in
nanotubes synthesized in the presence of boron. Our dynamical simulations lead
us to propose a mechanism through which this extension of the closure time can
be explained.

</DOC>
<DOC>
<DOCNO> 68089 </DOCNO>
Fourth generation effects in rare exclusive B -> K^* l^+ l^- decay


  Influence of the fourth generation, if ever exists, on the experimentally
measurable quantities such as invariant dilepton mass distribution, lepton
forward-backward asymmetry, and the ratio (Gamma_L/Gamma_T) of the decay widths
when K* meson is longitudinally and transversally polarized, is studied. Using
the experimental results on the branching ratios for the (B -> X_s) gamma and
semileptonic (B -> X_c l nu) decays, the two possible solutions of the 4x4
Cabibbo-Kobayashi-Maskawa factor (V_{t's} V_{t^'b}) are obtained as a function
of the t'-quark mass. It is observed that the results for the above-mentioned
physical quantities are essentially different from the standard model
predictions only for one solution of the CKM factor. In this case the
above-mentioned physical quantities can serve as efficient tools in search of
the fourth generation. The other solution yields almost identical results with
the SM.

</DOC>
<DOC>
<DOCNO> 12793 </DOCNO>
Charge-ordering and optical transitions of LiV2O5 and NaV2O5


  We present the measurements of the polarized optical spectra of NaV2O5 and
LiV2O5. In an energy range from 0.5 to 5.5 eV we observe similar peaks in the E
parallel a spectra of LiV2O5 and NaV2O5, which suggests similar electronic
structure along the a axis in both materials. On the other hand, we find an
almost complete suppression of the peaks in sigma_b of LiV2O5 around 1 and 5
eV. We attribute this suppression to the charge localization originating from
the existence of double-chain charge-ordering patterin in LiV2O5.

</DOC>
<DOC>
<DOCNO> 8467 </DOCNO>
Fractal Cosmology in an Open Universe


  The clustering of galaxies is well characterized by fractal properties, with
the presence of an eventual cross-over to homogeneity still a matter of
considerable debate. In this letter we discuss the cosmological implications of
a fractal distribution of matter, with a possible cross-over to homogeneity at
an undetermined scale R_{homo}. Contrary to what is generally assumed, we show
that, even when R_{homo} -> \infty, this possibility can be treated
consistently within the framework of the expanding universe solutions of
Friedmann. The fractal is a perturbation to an open cosmology in which the
leading homogeneous component is the cosmic background radiation (CBR). This
cosmology, inspired by the observed galaxy distributions, provides a simple
explanation for the recent data which indicate the absence of deceleration in
the expansion (q_o \approx 0). Correspondingly the `age problem' is also
resolved. Further we show that the model can be extended back from the
curvature dominated arbitrarily deep into the radiation dominated era, and we
discuss qualitatively the modifications to the physics of the anisotropy of the
CBR, nucleosynthesis and structure formation.

</DOC>
<DOC>
<DOCNO> 102756 </DOCNO>
Log-canonical forms and log canonical singularities


  For a normal subvariety $V$ of ${\bf C}^n$ with a good ${\bf C}^*$-action we
give a simple characterization for when it has only log canonical, log terminal
or rational singularities. Moreover we are able to give formulas for the
plurigenera of isolated singular points of such varieties and of the
logarithmic Kodaira dimension of $V\backslash \{0\}$. For this purpose we
introduce sheaves of $m$-canonical and $L^{2,m}$-canonical forms on normal
complex spaces. For the case of affine varieties with good ${\bf C}^*$-action
we give an explicit formula for these sheaves in terms of the grading of the
dualizing sheaf and its tensor powers.

</DOC>
<DOC>
<DOCNO> 13603 </DOCNO>
Phase oscillations in superfluid 3He-B weak links


  Oscillations in quantum phase about a mean value of $\pi$, observed across
micropores connecting two \helium baths, are explained in a Ginzburg-Landau
phenomenology. The dynamics arises from the Josephson phase relation,the
interbath continuity equation, and helium boundary conditions. The pores are
shown to act as Josephson tunnel junctions, and the dynamic variables are the
inter bath phase difference and fractional difference in superfluid density at
micropores. The system maps onto a non-rigid, momentum-shortened pendulum, with
inverted-orientation oscillations about a vertical tilt angle $\phi = \pi$, and
other modes are predicted.

</DOC>
<DOC>
<DOCNO> 118631 </DOCNO>
On Companion-Induced Off-Center Supernova-Like Explosions


  We suggest that a neutron star with a strong magnetic field, spiraling into
the envelope of a companion star, can generate a ``companion induced SN-like
off-center explosion". The strongly magnetized neutron star ("magnetar") is
born in a supernova explosion before entering into an expanding envelope of a
supergiant companion. If the neutron star collapses into a black hole via the
hypercritical accretion during the spiral-in phase, a rapidly rotating black
hole with a strong magnetic field at the horizon results. The Blandford-Znajek
power is sufficient to power a supernova-like event with the center of
explosion displaced from the companion core. The companion core, after
explosion, evolves into a C/O-white dwarf or a neutron star with a second
explosion. The detection of highly eccentric black-hole, C/O-white dwarf
binaries or the double explosion structures in the supernova remnants could be
an evidence of the proposed scenario.

</DOC>
<DOC>
<DOCNO> 100391 </DOCNO>
Approximation by quadrilateral finite elements


  We consider the approximation properties of finite element spaces on
quadrilateral meshes. The finite element spaces are constructed starting with a
given finite dimensional space of functions on a square reference element,
which is then transformed to a space of functions on each convex quadrilateral
element via a bilinear isomorphism of the square onto the element. It is known
that for affine isomorphisms, a necessary and sufficient condition for
approximation of order r+1 in L2 and order r in H1 is that the given space of
functions on the reference element contain all polynomial functions of total
degree at most r. In the case of bilinear isomorphisms, it is known that the
same estimates hold if the function space contains all polynomial functions of
separate degree r. We show, by means of a counterexample, that this latter
condition is also necessary. As applications we demonstrate degradation of the
convergence order on quadrilateral meshes as compared to rectangular meshes for
serendipity finite elements and for various mixed and nonconforming finite
elements.

</DOC>
<DOC>
<DOCNO> 71177 </DOCNO>
Luminosity monitors at the LHC


  We study the theoretical accuracy of various methods that have been proposed
to measure the luminosity of the LHC pp collider, as well as for Run II of the
Tevatron p barp collider. In particular we consider methods based on
  (i) the total and forward elastic data, (ii) lepton-pair production and (iii)
W and Z production.

</DOC>
<DOC>
<DOCNO> 67753 </DOCNO>
Scalable Parallel Implementation of Geant4 Using Commodity Hardware and


  We describe a scalable parallelization of Geant4 using commodity hardware in
a collaborative effort between the College of Computer Science and the
Department of Physics at Northeastern University. The system consists of a
Beowulf cluster of 32 Pentium II processors with 128 MBytes of memory each,
connected via ATM and fast Ethernet. The bulk of the parallelization is done
using TOP-C (Task Oriented Parallel C), software widely used in the
computational algebra community. TOP-C provides a flexible and powerful
framework for parallel algorithm development, is easy to learn, and is
available at no cost. Its task oriented nature allows one to parallelize legacy
code while hiding the details of interprocess communications. Applications
include fast interactive simulation of computationally intensive processes such
as electromagnetic showers. General results motivate wider applications of
TOP-C to other simulation problems as well as to pattern recognition in high
energy physics.

</DOC>
<DOC>
<DOCNO> 68021 </DOCNO>
Relic Gravitational Waves and Their Detection


  The range of expected amplitudes and spectral slopes of relic (squeezed)
gravitational waves, predicted by theory and partially supported by
observations, is within the reach of sensitive gravity-wave detectors. In the
most favorable case, the detection of relic gravitational waves can be achieved
by the cross-correlation of outputs of the initial laser interferometers in
LIGO, VIRGO, GEO600. In the more realistic case, the sensitivity of advanced
ground-based and space-based laser interferometers will be needed. The specific
statistical signature of relic gravitational waves, associated with the
phenomenon of squeezing, is a potential reserve for further improvement of the
signal to noise ratio.

</DOC>
<DOC>
<DOCNO> 14178 </DOCNO>
Corporate Default Behavior: A Simple Stochastic Model


  We compare observed corporate cumulative default probabilities to those
calculated using a stochastic model based on an extension of the work of Black
and Cox and find that corporations default as if via diffusive dynamics. The
model, based on a contingent-claims analysis of corporate capital structure, is
easily calibrated with readily available historical default probabilities and
fits observed default data published by Standard and Poor's. Applying this
model to the Standard and Poor's default data we find that the difference in
default behavior between credit ratings can be explained largely by a single
variable: the "distance to default" at the time the rating is given. The
ability to represent observed default behavior by a single analytic expression
and to differentiate credit-rating-dependent default behavior with a single
variable recommends this model for a variety of risk management applications
including the mapping of bank default experience to public credit ratings.

</DOC>
<DOC>
<DOCNO> 101970 </DOCNO>
A backward Monte-Carlo method for solving parabolic partial differential


  A new Monte-Carlo method for solving linear parabolic partial differential
equations is presented. Since, in this new scheme, the particles are followed
backward in time, it provides great flexibility in choosing critical points in
phase-space at which to concentrate the launching of particles and thereby
minimizing the statistical noise of the sought solution. The trajectory of a
particle, Xi(t), is given by the numerical solution to the stochastic
differential equation naturally associated with the parabolic equation. The
weight of a particle is given by the initial condition of the parabolic
equation at the point Xi(0). Another unique advantage of this new Monte-Carlo
method is that it produces a smooth solution, i.e. without delta-functions, by
summing up the weights according to the Feynman-Kac formula.

</DOC>
<DOC>
<DOCNO> 170433 </DOCNO>
Extended Version of "The Philosophy of the Trajectory Representation of


  The philosophy of the trajectory representation is contrasted with the
Copenhagen and Bohmian philosophies.

</DOC>
<DOC>
<DOCNO> 71707 </DOCNO>
Soft Resummation of Quark Anomalous Dimensions and Coefficient Functions


  The asymptotic behaviour at large N of the MS-bar quark anomalous dimensions
is derived to all orders assuming only MS-bar factorization and standard
results for the exponentiation of soft logarithms in the quark initiated bare
cross sections for deep inelastic scattering and Drell-Yan. The result is then
used to write the MS-bar quark coefficient functions in a form in which all
terms of $O(\ln^m N)$ are resummed.

</DOC>
<DOC>
<DOCNO> 12055 </DOCNO>
Ground-State Phase Diagram for the Three-Dimensional Orthogonal-Dimer


  We investigate quantum phase transitions in the three-dimensional
orthogonal-dimer system of the compound $\rm SrCu_2(BO_3)_2$ by means of the
series expansion technique. We then discuss the phase diagram where the dimer
phase, the Haldane phase, the frustration-induced disordered phase and the
magnetically ordered phase compete with each other. It is found that the
compound $\rm SrCu_2(BO_3)_2$ is located in the dimer phase close to the phase
boundary.

</DOC>
<DOC>
<DOCNO> 122789 </DOCNO>
The global structure of thin, stratified "alpha"-discs and the


  We report the results of a systematic comparison between the vertically
averaged model and the vertically explicit model of steady state, Keplerian,
optically thick "alpha"-discs. The simulations have concerned discs currently
found in three different systems: dwarf novae, young stellar objects and active
galactic nuclei. In each case, we have explored four decades of accretion rates
and almost the whole disc area
 (except the narrow region where the vertically averaged model has degenerate
solutions). We find that the one layer approach gives a remarkably good
estimate of the main physical quantities in the disc, and specially the
temperature at the equatorial plane which is accurate to within 30% for cases
considered. The major deviations (by a factor < 4) are observed on the disc
half-thickness. The sensitivity of the results to the "alpha"-parameter value
has been tested for 0.001 < alpha < 0.1 and appears to be weak. This study
suggests that the ``precision'' of the vertically averaged model which is easy
to implement should be sufficient in practice for many astrophysical
applications.

</DOC>
<DOC>
<DOCNO> 170249 </DOCNO>
Continuously Measured Systems,Path Integrals and Information


  A continuously measured quantum system may be described by restricted path
integrals (RPI) or equivalently by non-Hermitian Hamiltonians. The measured
system is then considered as an open system, the influence of the environment
being taken into account by restricting the path integral or by inclusion of an
imaginary part in the Hamiltonian. This way of description of measurements
naturally follows from the Feynman form of quantum mechanics without any
additional postulates and may be interpreted as an information approach to
continuous quantum measurements. This reveals deep features of quantum physics
concerning relations between quantum world and its classical appearance.

</DOC>
<DOC>
<DOCNO> 100719 </DOCNO>
Topology of billiard problems, I


  Let $T\subset \R^{m+1}$ be a strictly convex domain bounded by a smooth
hypersurface $X=\partial T$. In this paper we find lower bounds on the number
of billiard trajectories in $T$ which have a prescribed intial point $A\in X$,
a prescribed final point $B\in X$ and make a prescribed number $n$ of
reflections at the boundary $X$. We apply a topological approach based on
calculation of cohomology rings of certain configuration spaces.

</DOC>
<DOC>
<DOCNO> 11449 </DOCNO>
Interacting Stochastic Process and Renormalization Theory


  A stochastic process with self-interaction as a model of quantum field theory
is studied. We consider an Ornstein-Uhlenbeck stochastic process x(t) with
interaction of the form x^{(\alpha)}(t)^4, where $\alpha$ indicates the
fractional derivative. Using Bogoliubov's R-operation we investigate
ultraviolet divergencies for the various parameters $\alpha$. Ultraviolet
properties of this one-dimensional model in the case $\alpha=3/4$ are similar
to those in the $\phi^4_4$ theory but there are extra counterterms. It is shown
that the model is two-loops renormalizable. For $5/8\leq \alpha < 3/4$ the
model has a finite number of divergent Feynman diagrams. In the case
$\alpha=2/3$ the model is similar to the $\phi^4_3$ theory. If $0 \leq \alpha <
5/8$ then the model does not have ultraviolet divergencies at all. Finally if
$\alpha > 3/4$ then the model is nonrenormalizable. This model can be used for
a non-perturbative study of ultraviolet divergencies in quantum field theory
and also in theory of phase transitions.

</DOC>
<DOC>
<DOCNO> 13127 </DOCNO>
Order from disorder in the double-exchange model


  The magnetic excitations of the double exchange (DE) model are usually
discussed in terms of an equivalent ferromagnetic Heisenberg model. However
this equivalence is valid only at a quasi--classical level - we show that both
quantum and thermal corrections to the magnetic properties of DE model differ
from an effective Heisenberg model because its spin excitations interact only
indirectly, through the exchange of charge fluctuations. We also find that the
competition between ferromagnetic double exchange and an antiferromagnetic
superexchange provides a new example of an "order from disorder" phenomenon -
an intermediate spin configuration (either a canted or a spiral state) is
selected by quantum and/or thermal fluctuations.

</DOC>
<DOC>
<DOCNO> 11206 </DOCNO>
Analysis of the resonance peak and magnetic coherence seen in inelastic


  Assuming the exchange of antiferromagnetic spin fluctuations as the Cooper
pairing mechanism we calculate the doping dependence of the resonance peak seen
in inelastic neutron scattering and the magnetic coherence effect. Most
importantly, we find that the resonance peak in the magnetic susceptibility,
${Im}\chi({\bf q},\omega)$, appears {\it only} in the superconducting state,
that it scales with $T_c$, and that magnetic coherence is a result of a d-wave
order parameter. We further analyze the structure of ${Im}\chi$ below $T_c$,
the position of the peak at $\omega_{res}$ and the consequences for
photoemission, tunneling spectroscopy and the optical conductivity.

</DOC>
<DOC>
<DOCNO> 11525 </DOCNO>
Multifractal returns and Hierarchical Portfolio Theory


  We extend and test empirically the multifractal model of asset returns based
on a multiplicative cascade of volatilities from large to small time scales.
The multifractal description of asset fluctuations is generalized into a
multivariate framework to account simultaneously for correlations across times
scales and between a basket of assets. The reported empirical results show that
this extension is pertinent for financial modelling. The second part of the
paper applies this theory to portfolio optimisation. Our multi-scale
description allows us to characterize the portfolio return distribution at all
time scales simultaneously. The portfolio composition is predicted to change
with the investment time horizon (i.e., the time scale) in a way that can be
fully determined once an adequate measure of risk is chosen. We discuss the use
of the fourth-order cumulant and of utility functions. While the portfolio
volatility can be optimized in some cases for all time horizons, the kurtosis
and higher normalized cumulants cannot be simultaneously optimized. For a fixed
investment horizon, we study in details the influence of the number of periods,
i.e., of the number of rebalancing of the portfolio. For the large risks
quantified by the cumulants of order larger than two, the number of periods has
a non-trivial influence, in contrast with Tobin's result valid in the
mean-variance framework. This theory provides a fundamental framework for the
conflicting optimization involved in the different time horizons and quantifies
systematically the trade-offs for an optimal inter-temporal portfolio
optimization.

</DOC>
<DOC>
<DOCNO> 174578 </DOCNO>
Search for Strange Quark Matter Produced in Relativistic Heavy Ion


  We present the final results from Experiment 864 of a search for charged and
neutral strange quark matter produced in interactions of 11.5 GeV/c per nucleon
Au beams with Pt or Pb targets. Searches were made for strange quark matter
with A>4. Approximately 30 billion 10% most central collisions were sampled and
no strangelet states with A<100 were observed. We find 90% confidence level
upper limits of approximately 10^{-8} per central collision for both charged
and neutral strangelets. These limits are for strangelets with proper lifetimes
greater than 50 ns. Also limits for H^{0}-d and pineut production are given.
The above limits are compared with the predictions of various models. The
yields of light nuclei from coalescence are measured and a penalty factor for
the addition of one nucleon to the coalescing nucleus is determined. This is
useful in gauging the significance of our upper limits and also in planning
future searches for strange quark matter.

</DOC>
<DOC>
<DOCNO> 102836 </DOCNO>
One more proof of the Borodin-Okounkov formula for Toeplitz determinants


  Recently, Borodin and Okounkov established a remarkable identity for Toeplitz
determinants. Two other proofs of this identity were subsequently found by
Basor and Widom, who also extended the formula to the block case. We here give
one more proof, also for the block case. This proof is based on a formula for
the inverse of a finite block Toeplitz matrix obtained in the late seventies by
Silbermann and the author.

</DOC>
<DOC>
<DOCNO> 99949 </DOCNO>
Combinatorial Identities from the Spectral Theory of Quantum Graphs


  We present a few combinatorial identities which were encountered in our work
on the spectral theory of quantum graphs. They establish a new connection
between the theory of random matrix ensembles and combinatorics.

</DOC>
<DOC>
<DOCNO> 178609 </DOCNO>
Parity Nonconservation in the Deuteron Photodisintegration


  The paper has been withdrawn.

</DOC>
<DOC>
<DOCNO> 72274 </DOCNO>
Scalar partner of $Z^0$-boson with larger mass value than $Z^0$-boson


  The subquark model previously proposed by us showes that the intermediate
$Z^0$-boson is realized as the composite object and its scalar partner has
the mass value larger than $Z^0$-boson mass, which is about 110 GeV.

</DOC>
<DOC>
<DOCNO> 121618 </DOCNO>
The Canada-UK Deep Submillimetre Survey: The Survey of the 14-hour field


  We have used SCUBA to survey an area of 50 square arcmin, detecting 19
sources down to a 3sigma sensitivity limit of 3.5 mJy at 850 microns. We have
used Monte-Carlo simulations to assess the effect of source confusion and noise
on the SCUBA fluxes and positions, finding that the fluxes of sources in the
SCUBA surveys are significantly biased upwards and that the fraction of the 850
micron background that has been resolved by SCUBA has been overestimated. The
radio/submillmetre flux ratios imply that the dust in these galaxies is being
heated by young stars rather than AGN. We have used simple evolution models
based on our parallel SCUBA survey of the local universe to address the major
questions about the SCUBA sources: (1) what fraction of the star formation at
high redshift is hidden by dust? (2) Does the submillimetre luminosity density
reach a maximum at some redshift? (3) If the SCUBA sources are
proto-ellipticals, when exactly did ellipticals form? However, we show that the
observations are not yet good enough for definitive answers to these questions.
There are, for example, acceptable models in which 10 times as much
high-redshift star formation is hidden by dust as is seen at optical
wavelengths, but also acceptable ones in which the amount of hidden star
formation is less than that seen optically. There are acceptable models in
which very little star formation occurred before a redshift of three (as might
be expected in models of hierarchical galaxy formation), but also ones in which
30% of the stars have formed by this redshift. The key to answering these
questions are measurements of the dust temperatures and redshifts of the SCUBA
sources.

</DOC>
<DOC>
<DOCNO> 120372 </DOCNO>
Obscured Active Galactic Nuclei


  The properties of the absorption in type 2, narrow line AGNs are reviewed by
focusing on the X-ray indicators. I discuss the properties of the cold
absorbing medium (the putative torus) and of the reprocessed components, as
well as their implications for the unified model. The relation between optical
classification and X-ray absorption is examined. The case of "fossil" AGNs,
whose type 2 classification is not due to absorption effects, is also
discussed. Although this review is mainly focused on nearby Seyfert 2 galaxies,
I also shortly discuss the effects of absorption at higher luminosities and
higher redshift and the implications for the X-ray background.

</DOC>
<DOC>
<DOCNO> 122899 </DOCNO>
Numerical and Analytical Predictions for the Large-Scale


  The hot gas embedded in the large-scale structures in the Universe produces
secondary fluctuations in the Cosmic Microwave Background (CMB). Because it is
proportional to the gas pressure integrated along the line of sight, this
effect, the thermal Sunyaev-Zel'dovich (SZ) effect, provides a direct measure
of large-scale structure and of cosmological parameters. We study the
statistical properties of this effect using both hydrodynamical simulations and
analytical predictions from an extended halo model. The Adaptive Mesh
Refinement scheme, used in the newly developed code RAMSES, provides a dynamic
range of 4 order of magnitudes, and thus allows us to significantly improve
upon earlier calculations. After accounting for the finite mass resolution and
box size of the simulation, we find that the halo model agrees well with the
simulations. We discuss and quantify the uncertainty in both methods, and thus
derive an accurate prediction for the SZ power spectrum in the 10^2<l<10^5
range of multipole. We show how this combined analytical and numerical approach
is essential for accuracy, and useful for the understanding of the physical
processes and scales which contribute to large-scale SZ anisotropies.

</DOC>
<DOC>
<DOCNO> 9308 </DOCNO>
Excited Coherent Modes of Ultracold Trapped Atoms


  A method of exciting coherent spatial modes of Bose-condensed trapped atoms
is considered. The method is based on the resonance modulation of the trapping
potential. The population dynamics of coherent modes is analysed. The method
makes it possible to create mixtures of different spatial modes in arbitrary
proportions, including the formation of pure excited coherent modes. Novel
critical effects in the population dynamics are found.

</DOC>
<DOC>
<DOCNO> 8399 </DOCNO>
Toward a systematic 1/d expansion: Two particle properties


  We present a procedure to calculate 1/d corrections to the two-particle
properties around the infinite dimensional dynamical mean field limit. Our
method is based on a modified version of the scheme of Ref.
onlinecite{SchillerIngersent}}. To test our method we study the Hubbard model
at half filling within the fluctuation exchange approximation (FLEX), a
selfconsistent generalization of iterative perturbation theory. Apart from the
inherent unstabilities of FLEX, our method is stable and results in causal
solutions. We find that 1/d corrections to the local approximation are
relatively small in the Hubbard model.

</DOC>
<DOC>
<DOCNO> 152620 </DOCNO>
Living Inside the Horizon of the D3-Brane


  We consider a brane world residing in the interior region inside the horizon
of the D3-brane. The horizon size then can be interpreted as the
compactification size. The macroscopically large size of extra dimensions can
be derived from the underlying string theory that has only one physical scale,
{\it i.e.,} the string scale. Then, the hierarchy between the string scale and
the Planck scale is provided by Ramon-Ramon charge of the D3-brane. This
picture also offers a new perspective on various issues associated with the
brane world scenarios including the cosmological constant.

</DOC>
<DOC>
<DOCNO> 69772 </DOCNO>
CP Violation in Exclusive B Decays: Recoil Phase Effect


  In the perturbative QCD approach to exclusive B decays to two light mesons,
the leading twist contribution corresponds to those diagrams in the
Lepage-Brodsky expansion in which the would be spectator quark receives its
recoil momentum via one gluon exchange. We show that the resulting amplitude,
which in the spectator model is real, acquires an imaginary part which may be
comparable in size to its real part. Thus, this source of the strong
interaction phase in the amplitude must be taken into account in general to
discuss, reliably, the expectations for CP violation in B decays at any
B-Factory type scenario.

</DOC>
<DOC>
<DOCNO> 173956 </DOCNO>
Solvable and/or integrable and/or linearizable N-body problems in


  Several N-body problems in ordinary (3-dimensional) space are introduced
which are characterized by Newtonian equations of motion (``acceleration equal
force;'' in most cases, the forces are velocity-dependent) and are amenable to
exact treatment (``solvable'' and/or ``integrable'' and/or ``linearizable'').
These equations of motion are always rotation-invariant, and sometimes
translation-invariant as well. In many cases they are Hamiltonian, but the
discussion of this aspect is postponed to a subsequent paper. We consider
``few-body problems'' (with, say, \textit{N}=1,2,3,4,6,8,12,16,...) as well as
``many-body problems'' (N an arbitrary positive integer). The main focus of
this paper is on various techniques to uncover such N-body problems. We do not
discuss the detailed behavior of the solutions of all these problems, but we
do identify several models whose motions are completely periodic or multiply
periodic, and we exhibit in rather explicit form the solutions in some cases.

</DOC>
<DOC>
<DOCNO> 84161 </DOCNO>
The Angular Scale of Topologically-Induced Flat Spots in the Cosmic


  The notion that the topology of the universe need not be that of the
universal covering space of its geometry has recently received renewed
attention. Generic signatures of cosmological topology have been sought, both
in the distribution of objects in the universe, and especially in the
temperature fluctuations of the cosmic microwave background radiation (CMBR).
One signature identified in the horn topology but hypothesized to be generic is
featureless regions or flat spots in the CMBR sky. We show that typical
observation points within the cusped 3-manifold m003 from the Snappea census
have flat spots with an angular scale of about five degrees for $\Omega_0$=0.3.
We expect that this holds for other small volume cusped manifolds with this
$\Omega_0$ value.

</DOC>
<DOC>
<DOCNO> 101563 </DOCNO>
Hamiltonian stationary Lagrangian surfaces in C^2


  We study Hamiltonian stationary Lagrangian surfaces in C^2, i.e. Lagrangian
surfaces in C^2 which are stationary points of the area functional under smooth
Hamiltonian variations. Using loop groups, we propose a formulation of the
equation as a completely integrable system. We construct a Weierstrass type
representation and produce all tori through either the integrable systems
machinery or more direct arguments.

</DOC>
<DOC>
<DOCNO> 117878 </DOCNO>
On the origin of the color Tully-Fisher and color-magnitude relations of


  We propose and show that the dependence of the internal face-on dust
absorption upon B-band luminosity reported by Wang & Heckman (1996) for a
sample of late-type galaxies may explain the empirical color-magnitude and
color Tully-Fisher relations of disk galaxies. Thus, in order to explain these
relations, it is not necessary to evoke star formation and gas infall
efficiencies dependent on the mass of the galaxy system. After applying the
Wang & Heckman's luminosity-dependent extinction to hierarchical inside-out
galaxy formation and evolution models where the star formation and gas infall
efficiencies do not significantly depend on mass, we succesfully predict the
observed Tully-Fisher relations in the H and B bands as well as the
color-magnitude relation.

</DOC>
<DOC>
<DOCNO> 70030 </DOCNO>
The dynamics of the Goldstone bosons on the brane


  We study, within the recently proposed brane-world scenario, the effective
action for the low-energy brane excitations. These modes are understood as
Goldstone bosons associated to the spontaneous isometry breaking, induced on
the bulk space by the presence of the brane. Starting from the Nambu-Goto
action for the brane, we obtain a non-linear sigma model describing the
low-energy interactions of the Goldstone bosons and extend the calculation up
to O(p^4). We also discuss the Higgs-like mechanism in which the Kaluza-Klein
gauge fields absorb the Goldstone bosons and acquire mass. Finally, we present
the explicit form of the effective action describing the low-energy
interactions between the three-brane Goldstone bosons and the particles present
in the Standard Model.

</DOC>
<DOC>
<DOCNO> 40154 </DOCNO>
Spin Observables in Antilambda-Lambda Production from Antiproton-Proton


  The formalism describing the scattering of two spin-1/2 objects is reviewed
for the case of antilambda-lambda production from antiproton-proton
annihilation. It is shown that an experiment utilizing a transverse target
polarization can, in principle, completely determine the spin structure of the
reaction. Additional measurements, even those using both beam and target
polarizations, would not be sensitive to any additional spin dynamics. Thus,
the transverse target polarization allows access to the complete set of spin
observables, not just the subset upon which the literature has previously
focused. This discussion is especially relevant in light of the data collected
by PS185/3 at LEAR.

</DOC>
<DOC>
<DOCNO> 85118 </DOCNO>
The Formation of Supermassive Black Holes and the Evolution of


  The existence of supermassive black holes is supported by a growing body of
observations. Supermassive black holes and their formation events are likely
candidates for detection by proposed long-wavelength, space-based gravitational
wave interferometers like LISA. However, the nature of the progenitors of
supermassive black holes is rather uncertain. Supermassive black hole formation
scenarios that involve either the stellar dynamical evolution of dense clusters
or the hydrodynamical evolution of supermassive stars have been proposed. Each
of these formation scenarios is reviewed and the evolution of supermassive
stars is then examined in some detail. Supermassive stars that rotate uniformly
during their secular cooling phase will spin up to the mass-shedding limit and
eventually contract to the point of relativistic collapse. Supermassive stars
that rotate differentially as they cool will likely encounter the dynamical bar
mode instability prior to the onset of relativistic collapse. A supermassive
star that undergoes this bar distortion, prior to or during collapse, may be a
strong source of quasiperiodic, long-wavelength gravitational radiation.

</DOC>
<DOC>
<DOCNO> 7946 </DOCNO>
Dynamics of aeolian sand ripples


  We analyze theoretically the dynamics of aeolian sand ripples. In order to
put the study in the context we first review existing models. We argue on the
local character of sand ripple formation. Using a hydrodynamical model we
derive a nonlinear equation for the sand profile. We show how the
hydrodynamical model may be modified to recover the missing terms that are
dictated by symmetries. The symmetry and conservation arguments are powerful in
that the form of the equation is model-independent. We then present an
extensive numerical and analytical analysis of the generic sand ripple
equation. We find that at the initial stage the wavelength of the ripple is
that corresponding to the linearly most dangerous mode. At later stages the
profile undergoes a coarsening process leading to a significant increase of the
wavelength. We find that including the next higher order nonlinear term in the
equation, leads naturally to a saturation of the local slope. We analyze both
analytically and numerically the coarsening stage, in terms of a dynamical
exponent for the mean wavelength increase. We discuss some future lines of
investigations.

</DOC>
<DOC>
<DOCNO> 151310 </DOCNO>
Near-Extremal Correlators and Generalized Consistent Truncation for


  We present conjectures for the space-time form and leading large N dependence
of extremal and near-extremal correlation functions in the \N=8 superconformal
Yang-Mills theory in d=3 as well as in the (0,2) superconformal theory in d=6,
using their gravity duals with M-theory on $AdS_4\times \S^7$ and $AdS_7 \times
\S^4$ respectively. As a key part of the conjectures, we argue that the bulk
couplings associated with extremal and near-extremal field configurations in
the corresponding $AdS_4$ and $AdS_7$ gauged supergravities vanish. The
vanishing of these couplings constitutes a generalization of the property of
consistent truncation of the Kaluza-Klein modes.

</DOC>
<DOC>
<DOCNO> 120131 </DOCNO>
Entropy and holography constraints for inhomogeneous universes


  We calculated the entropy of a class of inhomogeneous dust universes.
Allowing spherical symmetry, we proposed a holographic principle by reflecting
all physical freedoms on the surface of the apparent horizon. In contrast to
flat homogeneous counterparts, the principle may break down in some models,
though these models are not quite realistic. We refined fractal parabolic
solutions to have a reasonable entropy value for the present observable
universe and found that the holographic principle always holds in the realistic
cases.

</DOC>
<DOC>
<DOCNO> 70755 </DOCNO>
External Magnetic Fields in QFT: A Non-Perturbative Approach


  A discussion of the influence of boundaries and scalar field interactions in
the non-perturbative dynamics of fermions in an external magnetic field, along
with their possible applications to condensed matter and cosmology, is briefly
presented. The significance of the results for electroweak baryogenesis in the
presence of an external magnetic field is indicated.

</DOC>
<DOC>
<DOCNO> 84955 </DOCNO>
Axisymmetric Simulations of Rotating Stellar Collapse in Full General


  Motivated by a recent paper by the Potsdam numerical relativity group, we
have constructed a new numerical code for hydrodynamic simulation of
axisymmetric systems in full general relativity. In this code, we solve the
Einstein field equation using Cartesian coordinates with appropriate boundary
conditions. On the other hand, the hydrodynamic equations are solved in
cylindrical coordinates. Using this code, we perform simulations to study
axisymmetric collapse of rotating stars, which thereby become black holes or
new compact stars, in full general relativity. To investigate the effects of
rotation on the criterion for prompt collapse to black holes, we first adopt a
polytropic equation of state, $P=K\rho^{\Gamma}$, where $P$, $\rho$, and $K$
are the pressure, rest mass density, and polytropic constant, with $\Gamma=2$.
In this case, the collapse is adiabatic (i.e., no change in entropy), and we
can focus on the bare effect of rotation. As the initial conditions, we prepare
rigidly and differentially rotating stars in equilibrium and then decrease the
pressure to induce collapse. In this paper, we consider cases in which $q
\equiv J/M_g^2 < 1$, where $J$ and $M_g$ are the angular momentum and the
gravitational mass. It is found that the criterion of black hole formation is
strongly dependent on the angular momentum parameter $q$. For $q < 0.5$, the
criterion is not strongly sensitive to $q$; more precisely, if the rest mass is
slightly larger than the maximum allowed value of spherical stars, a black hole
is formed. However, for $q \alt 1$, it changes significantly: For $q \simeq
0.9$, the maximum allowed rest mass becomes $\sim 70$ - 80% larger than that
for spherical stars.

</DOC>
<DOC>
<DOCNO> 99497 </DOCNO>
The Gervais-Neveu-Felder equation for the Jordanian quasi-Hopf


  Using a contraction procedure, we construct a twist operator that satisfies a
shifted cocycle condition, and leads to the Jordanian quasi-Hopf U_{h;y}(sl(2))
algebra. The corresponding universal ${\cal R}_{h}(y)$ matrix obeys a
Gervais-Neveu-Felder equation associated with the U_{h;y}(sl(2)) algebra. For a
class of representations, the dynamical Yang-Baxter equation may be expressed
as a compatibility condition for the algebra of the Lax operators.

</DOC>
<DOC>
<DOCNO> 120770 </DOCNO>
Updated AGASA event list above 4x10^19eV


  After our Ap.J. publication of the Akeno Giant Air Shower Array (AGASA)
results in 1999 (Takeda et al., 1999), we observed nine events with energies
above 4 $\times$ 10$^{19}$eV until May 2000. This short report lists the
coordinates of these events, and shows the updated energy spectrum and arrival
direction map. The analysis was carried out with the same procedure employed in
the Ap.J. publication.

</DOC>
<DOC>
<DOCNO> 13651 </DOCNO>
Generalized-Ensemble Algorithms for Molecular Simulations of Biopolymers


  In complex systems with many degrees of freedom such as peptides and proteins
there exist a huge number of local-minimum-energy states. Conventional
simulations in the canonical ensemble are of little use, because they tend to
get trapped in states of these energy local minima. A simulation in generalized
ensemble performs a random walk in potential energy space and can overcome this
difficulty. From only one simulation run, one can obtain canonical-ensemble
averages of physical quantities as functions of temperature by the
single-histogram and/or multiple-histogram reweighting techniques. In this
article we review uses of the generalized-ensemble algorithms. Three well-known
methods, multicanonical algorithm, simulated tempering, and replica-exchange
method, are described first. Both Monte Carlo and molecular dynamics versions
of the algorithms are given. We then present three new generalized-ensemble
algorithms which combine the merits of the above methods. The effectiveness of
the methods for molecular simulations in the protein folding problem is tested
with short peptide systems.

</DOC>
<DOC>
<DOCNO> 169749 </DOCNO>
The Modal Interpretation of Algebraic Quantum Field Theory


  In a recent article, Dieks has proposed a way to implement the modal
interpretation of (nonrelativistic) quantum theory in relativistic quantum
field theory. We show that his proposal fails to yield a well-defined
prescription for which observables in a local spacetime region possess definite
values. On the other hand, we demonstrate that there is a well-defined and
unique way of extending the modal interpretation to the local algebras of
relativistic quantum field theory. This extension, however, faces a potentially
serious difficulty in connection with ergodic states of a field.

</DOC>
<DOC>
<DOCNO> 70870 </DOCNO>
Thermalization temperature in Pb+Pb collisions at SpS energy from hadron


  In the frame of 2+1 Bjorken hydrodynamics we describe simultaneously hadron
yields and midrapidity pt distributions of direct photons, unflavored, and
strange hadrons measured in Pb+Pb collisions at SpS. We find, that a reasonably
quantitative description of these data is possible only if we introduce some
radial velocity at the beginning of the one-fluid hydrodynamic stage. We fix
uniquely all parameters of this model, and estimate an initial temperature of
the just thermalized state T_{in}=(200 +40 -20) MeV in the case of EoS with
phase transition to Quark-Gluon Plasma, and T_{in}=(230 +60 -30) MeV in the
pure hadronic scenario. We conclude that SpS data considered in our study can
not distinguish between a production of QGP, and its absence.

</DOC>
<DOC>
<DOCNO> 151978 </DOCNO>
Local Field Theory ON $\kappa$-Minkowski Space, Star Products and


  We consider local field theory on $\kappa$-deformed Minkowski space which is
an example of solvable Lie-algebraic noncommutative structure. Using
integration formula over $\kappa$-Minkowski space and $\kappa$-deformed Fourier
transform we consider for deformed local fields the reality conditions as well
as deformation of action functionals in standard Minkowski space. We present
explicite formulas for two equivalent star products describing CBH quantization
of field theory on $\kappa$-Minkowski space. We express also via star product
technique the noncommutative translations in $\kappa$-Minkowski space by
commutative translations in standard Minkowski space.

</DOC>
<DOC>
<DOCNO> 8113 </DOCNO>
Hysteresis measurement of anomalous microwave surface resistance in


  The anomalous decrease in microwave surface resistance, R_{s}, of
superconducting YBa_{2}Cu_{3}O_{7-d} (YBCO) thin films in the presence of a low
dc magnetic field is studied using a microstrip resonator technique. We have
done a dc field hysteresis measurement of R_{s} to study the effects of vortex
penetration on the anomalous effect. It is shown that the anomaly happens at a
field level far below the low critical field, H_{c1,strip}, of the
superconducting microstrip and vortex (Abrikosov) penetration would eliminate
the anomalous effect observed at low field. This implies that the anomalous
effect is not contributed by vortices.

</DOC>
<DOC>
<DOCNO> 10415 </DOCNO>
Multifractal Structure of the Sea-Bottom Topography in the Korean Sea


  The scaling behavior of the mutifractality for the sea-bottom topography of
the South Sea in Korea is numerically investigated. In particular, we focus on
the behavior of the $q$th-moment depth-depth correlation function of the
sea-bottom topography and its multifractal spectrum. Through the multifractal
analysis, the fractal dimension and the scaling exponents are obtained
numerically, and the relation between the Hurst exponent and the fractal
dimension is also derived.

</DOC>
<DOC>
<DOCNO> 101367 </DOCNO>
Conformal Field Theory and Doplicher-Roberts Reconstruction


  After a brief review of recent rigorous results concerning the representation
theory of rational chiral conformal field theories (RCQFTs) we focus on pairs
(A,F) of conformal field theories, where F has a finite group G of global
symmetries and A is the fixpoint theory. The comparison of the representation
categories of A and F is strongly intertwined with various issues related to
braided tensor categories. We explain that, given the representation category
of A, the representation category of F can be computed (up to equivalence) by a
purely categorical construction. The latter is of considerable independent
interest since it amounts to a Galois theory for braided tensor categories. We
emphasize the characterization of modular categories as braided tensor
categories with trivial center and we state a double commutant theorem for
subcategories of modular categories. The latter implies that a modular category
M which has a replete full modular subcategory M_1 is equivalent to M_1 x M_2
where M_2=M\cap M_1' is another modular subcategory. On the other hand, the
representation category of A is not determined completely by that of F and we
identify the needed additional data in terms of soliton representations. We
comment on `holomorphic orbifold' theories, i.e. the case where F has trivial
representation theory, and close with some open problems. We point out that our
approach permits the proof of many conjectures and heuristic results on `simple
current extensions' and `holomorphic orbifold models' in the physics literature
on conformal field theory.

</DOC>
<DOC>
<DOCNO> 13652 </DOCNO>
Exactly Solvable Three-body SUSY Systems with Internal Degrees of


  The approach of multi-dimensional SUSY Quantum Mechanics is used in an
explicit construction of exactly solvable 3-body (and quasi-exactly-solvable
$N$-body) matrix problems on a line. From intertwining relations with
time-dependent operators, we build exactly solvable non-stationary scalar and
$2\times 2$ matrix 3-body models which are time-dependent extensions of the
Calogero model. Finally, we investigate the invariant operators associated to
these systems.

</DOC>
<DOC>
<DOCNO> 174536 </DOCNO>
Production of $\eta\prime$ Mesons in the $pp \to pp\eta\prime$ Reaction


  The ratio of the total exclusive production cross sections for $\eta\prime$
and $\eta$ mesons has been measured in the $pp$ reaction at $p_{beam}=3.67$
GeV/c. The observed $\eta\prime/\eta$ ratio is
$(0.83\pm{0.11}^{+0.23}_{-0.18})\times 10^{-2}$ from which the exclusive
$\eta\prime$ meson production cross section is determined to be
$(1.12\pm{0.15}^{+0.42}_{-0.31})\mu b$. Differential cross section
distributions have been measured. Their shape is consistent with isotropic
$\eta\prime$ meson production.

</DOC>
<DOC>
<DOCNO> 102483 </DOCNO>
Singularities of special Lagrangian fibrations and the SYZ Conjecture


  The Strominger-Yau-Zaslow Conjecture, or SYZ Conjecture, explains Mirror
Symmetry between mirror Calabi-Yau 3-folds X,X' in terms of special Lagrangian
fibrations f : X --> B and f' : X' --> B over the same base B, whose fibres are
dual 3-tori, except for singular fibres.
  One of the main problems in proving the SYZ Conjecture (or even in finding
the right statement of it) is that the singularities of special Lagrangian
3-folds and fibrations are poorly understood. Most authors have supposed that
special Lagrangian fibrations f : X --> B will be smooth maps. This implies
that the singular fibres will be of codimension 2 in B, and that generic
singular fibres will be singular along a real curve.
  In this paper we study the singularities of special Lagrangian fibrations f :
X --> B when the Calabi-Yau 3-fold X is generic in a suitable sense. We claim
that such fibrations are only piecewise smooth, with singular fibres of
codimension 1 in B, and that all singular fibres are singular at only finitely
many points.
  To justify this claim we construct non-smooth local models in C^3 for various
kinds of singularities of special Lagrangian fibrations f : X --> B. For
codimension 1 singularities our models are entirely explicit, but for
codimension 2 they depend on a conjecture about solutions to a nonlinear
Cauchy-Riemann equation.
  Our conclusions, which depend on conjectures made along the way, contradict
the stronger current forms of the SYZ Conjecture.

</DOC>
<DOC>
<DOCNO> 102063 </DOCNO>
On Validated Numeric of Values of Some Zeta and L-functions, and


  This paper describes some validated numerics aspects of Riemann zeta
function, Dirichlet L-functions, Dedekind zeta functions and Hasse-Weil
L-functions.

</DOC>
<DOC>
<DOCNO> 101526 </DOCNO>
Combinatorial Dehn surgery on cubed and Haken 3-manifolds


  A combinatorial condition is obtained for when immersed or embedded
incompressible surfaces in compact 3-manifolds with tori boundary components
remain incompressible after Dehn surgery. A combinatorial characterisation of
hierarchies is described. A new proof is given of the topological rigidity
theorem of Hass and Scott for 3-manifolds containing immersed incompressible
surfaces, as found in cubings of non-positive curvature.

</DOC>
<DOC>
<DOCNO> 39637 </DOCNO>
The H1 Forward Proton Spectrometer at HERA


  The forward proton spectrometer is part of the H1 detector at the HERA
collider. Protons with energies above 500 GeV and polar angles below 1 mrad can
be detected by this spectrometer. The main detector components are
scintillating fiber detectors read out by position-sensitive photo-multipliers.
These detectors are housed in so-called Roman Pots which allow them to be moved
close to the circulating proton beam. Four Roman Pot stations are located at
distances between 60 m and 90 m from the interaction point.

</DOC>
<DOC>
<DOCNO> 151823 </DOCNO>
Casimir energy for a scalar field with a frequency dependent boundary


  We consider the vacuum energy for a scalar field subject to a frequency
dependent boundary condition. The effect of a frequency cut-off is described in
terms of an {\it incomplete} $\zeta$-function. The use of the Debye asymptotic
expansion for Bessel functions allows to determine the dominant (volume, area,
>...) terms in the Casimir energy. The possible interest of this kind of models
for dielectric media (and its application to sonoluminescence) is also
discussed.

</DOC>
<DOC>
<DOCNO> 119833 </DOCNO>
Impact of Few-Body Reactions on Explosive Nucleosynthesis: The Big-Bang


  We study the few body reactions in explosive nucleosynthesis of
light-to-heavy mass elements in various astrophysical conditions. In
neutrino-driven winds of gravitational core collapse of SNeII, several light
nuclei as well as heavy unstable nuclei paly significant roles in producing
r-process elements. We discuss how the three-body reaction $^4$He$(\alpha n,
\gamma)^9$Be, whose cross section is poorly known, plays very critical role. We
make note that several other reactions in the r-process are relevant to a
Big-Bang nucleosynthesis. We discuss briefly a Galactic chemical evolution.

</DOC>
<DOC>
<DOCNO> 123114 </DOCNO>
Detection of massive tidal tails around the globular cluster Pal 5 with


  We report the discovery of two well-defined tidal tails emerging from the
sparse remote globular cluster Palomar 5. These tails stretch out symmetrically
to both sides of the cluster in the direction of constant Galactic latitude and
subtend an angle of 2.6 degrees on the sky. The tails have been detected in
commissioning data of the Sloan Digital Sky Survey (SDSS), providing deep
five-color photometry in a 2.5 degrees wide band along the equator. The stars
in the tails make up a substantial part (~1/3) of the current total population
of cluster stars in the magnitude interval 19.5 < i* < 22.0. This reveals that
the cluster is subject to heavy mass loss. The orientation of the tails
provides an important key for the determination of the cluster's Galactic
orbit.

</DOC>
<DOC>
<DOCNO> 101424 </DOCNO>
Standard-Model Bundles on Non-Simply Connected Calabi--Yau Threefolds


  We give a proof of the existence of $G=SU(5)$, stable holomorphic vector
bundles on elliptically fibered Calabi--Yau threefolds with fundamental group
$\bbz_2$. The bundles we construct have Euler characteristic 3 and an anomaly
that can be absorbed by M-theory five-branes. Such bundles provide the basis
for constructing the standard model in heterotic M-theory. They are also
applicable to vacua of the weakly coupled heterotic string. We explicitly
present a class of three family models with gauge group $SU(3)_C\times
SU(2)_L\times U(1)_Y$.

</DOC>
<DOC>
<DOCNO> 122772 </DOCNO>
The 2000 outburst of the recurrent nova CI Aquilae: optical spectroscopy


  We present low- and medium resolution spectra of the recurrent nova CI
Aquilae taken at 14 epochs in May and June, 2000. The overall appearance is
similar to other U Sco-type recurrent novae (U Sco, V394 CrA). Medium
resolution (R=7000-10000) hydrogen and iron profiles suggest an early expansion
velocity of 2000-2500 km/s. The H\alpha evolution is followed from Dt = -0.6 d
to +53 d, starting from a nearly Gaussian shape to a double peaked profile
through strong P-Cyg profiles. The interstellar component of the sodium D line
and two diffuse interstellar bands put constraints on the interstellar
reddening which is estimated to be E(B-V)=0.85\pm0.3. The available visual and
CCD-V observations are used to determine t0,t2 and t3. The resulting parameters
are: t0=2451669.5\pm0.1, t2=30\pm1 d, t3=36\pm1 d. The recent lightcurve is
found to be generally similar to that observed in 1917 with departures as large
as 1-2 mag in certain phases. This behaviour is also typical for the U Sco
subclass.

</DOC>
<DOC>
<DOCNO> 178902 </DOCNO>
Ferromagnetism of Nuclear Matter in the Relativistic Approach


  We study the spin-polarization mechanism in the highly dense nuclear matter
with the relativistic mean-field approach. In the relativistic Hartree-Fock
framework we find that there are two kinds of spin-spin interaction channels,
which are the axial-vector and tensor exchange ones. If each interaction is
strong and different sign, the system loses the spherical symmetry and holds
the spin-polarization in the high-density region. When the axial-vector
interaction is negative enough, the system holds ferromagnetism.

</DOC>
<DOC>
<DOCNO> 123045 </DOCNO>
ORFEUS echelle spectra: Molecular hydrogen in disk, IVC, and HVC gas in


  In front of the LMC molecular hydrogen is found in absorption near 0 km/s,
being local disk gas, near +60 km/s in an intermediate velocity cloud, and near
+120 km/s, in a high velocity halo cloud. The nature of the gas is discussed
based on four ORFEUS far UV spectra of LMC stars and including data from the
ground and from the IUE satellite. The local gas is cool and, given a span of
sight lines of only 2.5 deg, rather fluffy. The fractional abundance of H_2
varies from log(f)=-5.4 to -3.3. Metal depletions (up to -1.7 dex for Fe) are
typical for galactic disk gas. In the IV and HV gas an apparent underabundance
of neutral oxygen points to an ionization level of the gas of about 90%. H_2 is
detected in IV and HV gas toward HD 269546. In the IV gas we find an H_2 column
density of log(N)\simeq15.6. The H_2 excitation indicates that the line of
sight samples a cloud at a temperature below 150 K. Column densities are too
small to detect the higher UV pumped excitation levels. The high velocity H_2
(log(N)\simeq15.6) is highly excited and probably exposed to a strong radiation
field. Its excitation temperature exceeds 1000 K. Due to the radial velocity
difference between the halo gas and the Milky Way disk, the unattenuated disk
radiation is available for H_2 excitation in the halo. We do not find evidence
for an intergalactic origin of this gas; a galactic as well as a Magellanic
Cloud origin is possible.

</DOC>
<DOC>
<DOCNO> 71872 </DOCNO>
Physics of the Nucleon Sea Quark Distributions


  Sea quark distributions in the nucleon have naively been expected to be
generated perturbatively by gluon splitting. In this case, there is no reason
for the light quark and anti-quark sea distributions to be different. No
asymmetries in the strange or heavy quark sea distributions are predicted in
the improved parton model. However, recent experiments have called these naive
expectations into question. A violation of the Gottfried sum rule has been
measured in several experiments, suggesting that $\bar u < \bar d$ in the
proton. Additionally, other measurements, while not definitive, show that there
may be an asymmetry in the strange and anti-strange quark sea distributions.
These effects may require nonperturbative explanations. In this review we first
discuss the perturbative aspects of the sea quark distributions. We then
describe the experiments that could point to nonperturbative contributions to
the nucleon sea. Current phenomenological models that could explain some of
these effects are reviewed.

</DOC>
<DOC>
<DOCNO> 117442 </DOCNO>
The PSCz Catalogue


  We present the catalogue, mask, redshift data and selection function for the
PSCz survey of 15411 IRAS galaxies across 84% of the sky. Most of the IRAS data
is taken from the Point Source Catalog, but this has been supplemented and
corrected in various ways to improve the completeness and uniformity. We
quantify the known imperfections in the catalogue, and we assess the overall
uniformity, completeness and data quality. We find that overall the catalogue
is complete and uniform to within a few percent at high latitudes and 10% at
low latitudes. Ancillary information, access details, guidelines and caveats
for using the catalogue are given.

</DOC>
<DOC>
<DOCNO> 119920 </DOCNO>
The Type Ia Supernova Width-Luminosity Relation


  Observations of type Ia supernovae at high redshifts have become an important
tool for studying the geometry of the universe. The relation between the
duration of the peak phase of a type Ia supernova's lightcurve and its
luminosity (broader is brighter) forms the cornerstone of this measurement, yet
it is a purely empirical relation. In this paper we show that the relation is a
natural consequence of the radiation transport in type Ia supernovae and
suggest constraints on the nature of the explosions which arise from our
interpretation of the observed relation. The principle parameter underlying the
relation is the mass of radioactive 56Ni produced in the explosion. The
relation is shown to be relatively insensitive to most other parameters in
Chandrasekhar-mass explosions. Cosmological results are thus unlikely to suffer
from systematic effects stemming from evolution in the explosions' progenitors.

</DOC>
<DOC>
<DOCNO> 119398 </DOCNO>
Age difference between the populations of binary and single F~stars


  We have compared the kinematics and metallicity of the main sequence binary
and single {\it uvby} F stars from the {\it HIPPARCOS} catalog to see if the
populations of these stars originate from the same statistical ensemble. The
velocity dispersions of the known unresolved binary F stars have been found to
be dramatically smaller than those of the single F stars. This suggests that
the population of these binaries is, in fact, younger than that of the single
stars, which is further supported by the difference in metal abundance: the
binaries turn out to be, on average, more metal rich than the single stars. So,
we conclude that the population of these binaries is indeed {\it younger} than
that of the single F stars. Comparison of the single F stars with the C
binaries (binary candidates identified in Suchkov & McMaster 1999) has shown,
on the other hand, that the latter stars are, on average, {\it older} than the
single F stars. We suggest that the age difference between the single F stars,
known unresolved binaries, and C binaries is associated with the fact that
stellar evolution in a binary systems depends on the binary components mass
ratio and separation, with these parameters being statistically very different
for the known binaries and C binaries (e.g., mostly substellar secondaries in C
binaries versus stellar secondaries in known binaries).
  In general we conclude that the populations of known binaries, C binaries,
and single F stars do not belong to the same statistical ensemble. The
implications of the discovered age difference between these populations along
with the corresponding differences in kinematics and metallicity should be
important not only for understanding the evolution of stars but also for the
history of star formation and the evolution of the local galactic disk.

</DOC>
<DOC>
<DOCNO> 70460 </DOCNO>
Hard and soft QCD in charmonium production


  We show that both hard perturbative and soft non-perturbative QCD effects are
important in hadroproduction of charmonium. Observed $x_F$ and $p_\perp$
distributions of J/psi in fixed target experiments can be well described by our
Monte Carlo model based on perturbative QCD and the Color Evaporation Model.

</DOC>
<DOC>
<DOCNO> 121079 </DOCNO>
Conditions for Shock Revival by Neutrino Heating in Core-Collapse


  Energy deposition by neutrinos can rejuvenate the stalled bounce shock and
can provide the energy for the supernova explosion of a massive star. This
neutrino-heating mechanism, however, is not finally accepted or proven as the
trigger of the explosion. Part of the problem is that the complexity of the
hydrodynamic models often hampers a clear and simple interpretation of the
results. This demands a deeper theoretical understanding of the requirements of
a successful shock revival. A toy model is presented here for discussing the
neutrino heating phase analytically by a time-dependent treatment, which allows
one to calculate the radius and velocity of the supernova shock from global
properties of the gain layer as solutions of an initial value problem. A
criterion is derived for the requirements of shock revival. It confirms the
existence of a minimum neutrino luminosity needed for shock expansion, but also
demonstrates the importance of a sufficiently large mass infall rate to the
shock. The possibility of very energetic neutrino-driven explosions seems
excluded because the total specific energy transferred to nucleons is limited
by about 1e52 ergs per solar mass (about 5 MeV per nucleon) and the total mass
in the gain layer is typically only around 0.1 solar masses. Energy transport
by convection from the region of maximum heating to radii closer behind the
shock is found to support the explosion by reducing the energy loss associated
with the inward advection of neutrino-heated matter through the gain radius.
(abridged)

</DOC>
<DOC>
<DOCNO> 85278 </DOCNO>
Energy of a Conformal Scalar Dyon Black Hole


  We obtain the energy of a conformal scalar dyon black hole (CSD) by using the
energy-momentum complexes of Tolman and M{\o}ller. The total gravitational
energy is given by the CSD charge in the both prescriptions.

</DOC>
<DOC>
<DOCNO> 9983 </DOCNO>
Analysis of Dislocation Mechanism for Melting of Elements: Pressure


  In the framework of melting as a dislocation-mediated phase transition we
derive an equation for the pressure dependence of the melting temperatures of
the elements valid up to pressures of order their ambient bulk moduli. Melting
curves are calculated for Al, Mg, Ni, Pb, the iron group (Fe, Ru, Os), the
chromium group (Cr, Mo, W), the copper group (Cu, Ag, Au), noble gases (Ne, Ar,
Kr, Xe, Rn), and six actinides (Am, Cm, Np, Pa, Th, U). These calculated
melting curves are in good agreement with existing data. We also discuss the
apparent equivalence of our melting relation and the Lindemann criterion, and
the lack of the rigorous proof of their equivalence. We show that the would-be
mathematical equivalence of both formulas must manifest itself in a new
relation between the Gr\"{u}neisen constant, bulk and shear moduli, and the
pressure derivative of the shear modulus.

</DOC>
<DOC>
<DOCNO> 178670 </DOCNO>
On the mechanisms of superfluidity in atomic nuclei


  A system of equations is obtained for the Cooper gap in nuclei. The system
takes two mechanisms of superfluidity into account in an approximation
quadratic in the phonon- production amplitude : a Bardeen- Cooper- Schrieffer
(BCS) type mechanism and a quasiparticle- phonon mechanism. These equations are
solved for 120 Sn in a realistic approximation. If the simple procedures
proposed are used to determine the new particle- particle interaction and to
estimate the average effect, then the contribution of the quasiparticle- phonon
mechanism to the observed width of the pairing gap is 26% and the BCS-type
contribution is 74%. This means that at least in semimagic nuclei pairing is of
a mixed nature - it is due to the two indicated mechanisms, the first being
mainly a surface mechanism and the second mainly a volume mechanism.

</DOC>
<DOC>
<DOCNO> 99778 </DOCNO>
Tournament Sequences and Meeussen Sequences


  A "tournament sequence" is an increasing sequence of positive integers
(t_1,t_2,...) such that t_1=1 and t_{i+1} <= 2 t_i. A "Meeussen sequence" is an
increasing sequence of positive integers (m_1,m_2,...) such that m_1=1, every
nonnegative integer is the sum of a subset of the {m_i}, and each integer m_i-1
is the sum of a unique such subset.
  We show that these two properties are isomorphic. That is, we present a
bijection between tournament and Meeussen sequences which respects the natural
tree structure on each set. We also present an efficient technique for counting
the number of tournament sequences of length n, and discuss the asymptotic
growth of this number. The counting technique we introduce is suitable for
application to other well-behaved counting problems of the same sort where a
closed form or generating function cannot be found.

</DOC>
<DOC>
<DOCNO> 11294 </DOCNO>
Optical study of the electronic phase transition of strongly correlated


  Infrared, visible and near-UV reflectivity measurements are used to obtain
conductivity as a function of temperature and frequency in YbInCu_4, which
exhibits an isostructural phase-transition into a mixed-valent phase below
T_v=42 K. In addition to a gradual loss of spectral weight with decreasing
temperature extending up to 1.5 eV, a sharp resonance appears at 0.25 eV in the
mixed-valent phase. This feature can be described in terms of excitations into
the Kondo (Abrikosov-Suhl) resonance, and, like the sudden reduction of
resistivity, provides a direct reflection of the onset of coherence in this
strongly correlated electron system.

</DOC>
<DOC>
<DOCNO> 122280 </DOCNO>
The structure of the Universe on 100 Mpc Scales


  Observational evidence for the presence of a preferred scale around 100 Mpc
in the distribution of high-density regions in the Universe is summarised. Toy
models with various degrees of regularity are analysed to understand better the
observational data. Predictions of models which produce a feature on the
initial power spectrum of matter are analysed and compared with new
observational data on the CMB angular spectrum, cluster mass function, and
galaxy and cluster power spectrum.

</DOC>
<DOC>
<DOCNO> 121850 </DOCNO>
Iron K-alpha Emission from a Decaying Magnetar Model of Gamma-Ray Bursts


  The recent report of X-ray Fe features in the afterglow of the gamma-ray
burst GRB 991216 may provide important clues for identifying the nature of its
progenitor and constraining the burst mechanism. We argue that the strong line
emission can be attributed to the interaction of a continuing (but decaying)
post-burst relativistic outflow from the central engine with the progenitor
stellar envelope at distances less than a light-hour. Only a small mass of Fe
is then required, which could have been readily produced by the star itself.

</DOC>
<DOC>
<DOCNO> 122451 </DOCNO>
Star Formation-Regulated Growth of Black Holes in Protogalactic


  The observed relation between central black hole mass and spheroid velocity
dispersion is interpreted in terms of a self-regulation model that incorporates
a viscous Keplerian accretion disk to feed the black hole, embedded in a
massive, self-gravitating star forming disk that eventually populates the
spheroid. The model leads to a constant ratio between black hole mass and
spheroid mass which is equal to the inverse of the critical Reynolds number for
the onset of turbulence in the accretion disk surrounding the central black
hole. Applying the fundamental plane correlation for spheroids, we find that
the black hole mass has a power-law dependence on the spheroid velocity
dispersion with a slope in the range of 4-5. We explain the larger scatter in
the Magorrian relation with respect to the black hole mass-spheroid velocity
dispersion relationship as a result of secular evolution of the spheroid that
primarily affects its luminosity and to a much lesser extent its velocity
dispersion.

</DOC>
<DOC>
<DOCNO> 100594 </DOCNO>
On the fine structure of stationary measures in systems which


  Suppose $\{f_1,...,f_m\}$ is a set of Lipschitz maps of $\mathbb{R}^d$. We
form the iterated function system (IFS) by independently choosing the maps so
that the map $f_i$ is chosen with probability $p_i$ ($\sum_{i=1}^m p_i=1$). We
assume that the IFS contracts on average. We give an upper bound for the
Hausdorff dimension of the invariant measure induced on $\mathbb{R}^d$ and as a
corollary show that the measure will be singular if the modulus of the entropy
$\sum_i p_i \log p_i$ is less than $d$ times the modulus of the Lyapunov
exponent of the system. Using a version of Shannon's Theorem for random walks
on semigroups we improve this estimate and show that it is actually attainable
for certain cases of affine mappings of $\mathbb{R}$.

</DOC>
<DOC>
<DOCNO> 13193 </DOCNO>
Comparison of structural transformations and superconductivity in


  Density-functional calculations are presented for high-pressure structural
phases of S and Se. The structural phase diagrams, phonon spectra,
electron-phonon coupling, and superconducting properties of the isovalent
elements are compared. We find that with increasing pressure, Se adopts a
sequence of ever more closely packed structures (beta-Po, bcc, fcc), while S
favors more open structures (beta-Po, simple cubic, bcc). These differences are
shown to be attributable to differences in the S and Se core states. All the
compressed phases of S and Se considered are calculated to have weak to
moderate electron-phonon coupling strengths consistent with superconducting
transition temperatures in the range of 1 to 20 K. Our results compare well
with experimental data on the beta-Po --> bcc transition pressure in Se and on
the superconducting transition temperature in beta-Po S. Further experiments
are suggested to search for the other structural phases predicted at higher
pressures and to test theoretical results on the electron-phonon interaction
and superconducting properties.

</DOC>
<DOC>
<DOCNO> 122404 </DOCNO>
The XMM-Newton Serendipitous Survey I. The role of XMM-Newton Survey


  This paper describes the performance of XMM-Newton for serendipitous surveys
and summarises the scope and potential of the XMM-Newton Serendipitous Survey.
The role of the Survey Science Centre (SSC) in the XMM-Newton project is
outlined. The SSC's follow-up and identification programme for the XMM-Newton
serendipitous survey is described together with the presentation of some of the
first results.

</DOC>
<DOC>
<DOCNO> 9681 </DOCNO>
Structures and melting in infinite gold nanowires


  The temperature dependence of structural properties for infinitely long gold
nanowires is studied. The molecular dynamics simulation method and the
embedded-atom potential are used. The wires constructed at T=0 K with a
face-centered cubic structure and oriented along the (111), (110), and (100)
directions are investigated. It was found that multiwalled structures form in
all these nanowires. The coaxial cylindrical shells are the most pronounced and
well-formed for an initial fcc(111) orientation. The shells stabilize with
increasing temperature above 300 K. All nanowires melt at T<1100 K, i.e., well
below the bulk melting temperature.

</DOC>
<DOC>
<DOCNO> 151139 </DOCNO>
On the Trace Anomaly as a Measure of Degrees of Freedom


  Recent conjectures of the c-theorem in four and higher dimensions have
suggested that the coefficient of the Euler characteristic in the trace anomaly
could measure the degrees of freedom in field theory and decrease along the
renormalization-group flow. We compute this quantity for free massless scalar,
fermion and antisymmetric tensor fields in any dimension, and analyse its
dependence on spin and space-time dimension. In the limit of large number of
dimensions, where the theories become semiclassical, we find that this quantity
does not approach the classical number of field components, but is enhanced for
spinful particles. This seemingly strange behaviour is found to be consistent
with known renormalization-group patterns and a specific c-theorem conjecture.

</DOC>
<DOC>
<DOCNO> 102809 </DOCNO>
Sous-groupes paraboliques et representations de groupes branches


  Let G be a branch group (as defined by Grigorchuk) acting on a tree T. A
parabolic subgroup P is the stabiliser of an infinite geodesic ray in T. We
denote by $\rho_{G/P}$ the associated quasi-regular representation.
  If G is discrete, these representations are irreducible, but if G is
profinite, they split as a direct sum of finite-dimensionalrepresentations
$\rho_{G/P_{n+1}}\ominus\rho_{G/P_n}$, where P_n is the stabiliser of a level-n
vertex in T.
  For a few concrete examples, we completely split $\rho_{G/P_n}$ in
irreducible components. $(G,P_n)$ and $(G,P)$ are Gelfand pairs, whence new
occurrences of abelian Hecke algebra.

</DOC>
<DOC>
<DOCNO> 118438 </DOCNO>
Stellar parameters from very low resolution spectra and medium band


  Large scale, deep survey missions such as GAIA will collect enormous amounts
of data on a significant fraction of the stellar content of our Galaxy. These
missions will require a careful optimisation of their observational systems in
order to maximise their scientific return, and will require reliable and
automated techniques for parametrizing the very large number of stars detected.
To address these two problems, I investigate the precision to which the three
principal stellar parameters (Teff, logg, [M/H]) can be determined as a
function of spectral resolution and signal-to-noise (SNR) ratio, using a large
grid of synthetic spectra. The parametrization technique is a neural network,
which is shown to provide an accurate three-dimensional physical
parametrization of stellar spectra across a wide range of parameters. It is
found that even at low resolution (50-100 AA FWHM) and SNR (5-10 per resolution
element), Teff and \met can be determined to 1% and 0.2 dex respectively across
a large range of temperatures (4000-30000 K) and metallicities (-3.0 to +1.0
dex), and that logg is measurable to +/- 0.2 dex for stars earlier than solar.
The accuracy of the results is probably limited by the finite parameter
sampling of the data grid. The ability of medium band filter systems (with
10-15 filters) for determining stellar parameters is also investigated.
Although easier to implement in a unpointed survey, it is found that they are
only competitive at higher SNRs (> 50).

</DOC>
<DOC>
<DOCNO> 69053 </DOCNO>
Eikonal Scattering of Monopoles and Dyons in Dual QED


  The quantum field theory of electron-point magnetic monopole interactions and
dyon-dyon interactions, based on the string-dependent ``nonlocal'' action of
Dirac and Schwinger is developed. We demonstrate that a nonperturbative quantum
field theoretic formulation can be constructed resulting in a string {\em
independent} cross section for monopole-electron and dyon-dyon scattering. Such
calculations can be done only by using nonperturbative approximations such as
the eikonal and not by some mutilation of lowest-order perturbation theory.

</DOC>
<DOC>
<DOCNO> 70046 </DOCNO>
Effective Field Theories, Landau-Migdal Fermi-Liquid Theory and


  We reinterpret Landau-Migdal Fermi-liquid theory of nuclear matter as an
effective chiral field theory with a Fermi surface. The effective field theory
is formulated in terms of a chiral Lagrangian with its {\it mass and coupling
parameters} scaling a la Brown-Rho and with the Landau-Migdal parameters
identified as the fixed points of the field theory. We show how this mapping
works out for response functions to the EM vector current and then using the
same reasoning, make prediction on nuclear axial current, in particular on the
enhanced axial-charge transitions in heavy nuclei. We speculate on how to
extrapolate the resulting theory which appears to be sound both theoretically
and empirically up to normal nuclear matter density $\rho_0$, to hitherto
unexplored higher density regime relevant to relativistic heavy-ion processes
and to cold compact (neutron) stars.

</DOC>
<DOC>
<DOCNO> 178628 </DOCNO>
Coulomb and nuclear breakup of three-body halo nuclei


  We investigate dissociation reactions of loosely bound and spatially extended
three-body systems. We formulate a practical method for simultaneous treatment
of long-range Coulomb and short-range nuclear interactions. We use $^6$He
(n+n+$\alpha$) and $^{11}$Li (n+n+$^{9}$Li) as examples and study the
two-neutron separation cross sections as functions of target and beam energy.
Individual Coulomb and nuclear as well as interference contributions are also
extracted.

</DOC>
<DOC>
<DOCNO> 8913 </DOCNO>
Random magnetic field and quasi-particle transports in the mixed state


  By a singular gauge transformation, the quasi-particle transport in the mixed
state of high T_{c} cuprates is mapped into charge-neutral composite Dirac
fermion moving in short-range correlated random scalar and long-range
correlated vector potential. A fully quantum mechanical approach to
longitudinal and transverse thermal conductivities is presented. The
semi-classical Volovik effect is presented in a quantum mechanical way. The
quasi-particle scattering from the random magnetic field which was completely
missed in all the previous semi-classical approaches is the dominant scattering
mechanism at sufficiant high magnetic field. The implications for experiments
are discussed.

</DOC>
<DOC>
<DOCNO> 12458 </DOCNO>
Pressure dependence of the spin gap in BaVS_3


  We carried out magnetotransport experiments under hydrostatic pressure in
order to study the nature of the metal-insulator transition in BaVS$_3$.
Scaling relations for $\rho(T,H,p)$ are established and the pressure dependence
of the spin gap is determined. Our new results, in conjunction with a
re-analysis of earlier specific heat and susceptibility data, demonstrate that
the transition is weakly second order. The nature of the phase diagram in the
$T$--$p$--$H$ space is discussed.

</DOC>
<DOC>
<DOCNO> 101948 </DOCNO>
Avoided crossings in mesoscopic systems: electron propagation on a


  We consider an electron constrained to move on a surface with revolution
symmetry in the presence of a constant magnetic field $B$ parallel to the
surface axis. Depending on $B$ and the surface geometry the transverse part of
the spectrum typically exhibits many crossings which change to avoided
crossings if a weak symmetry breaking interaction is introduced. We study the
effect of such perturbations on the quantum propagation. This problem admits a
natural reformulation to which tools from molecular dynamics can be applied. In
turn, this leads to the study of a perturbation theory for the time dependent
Born-Oppenheimer approximation.

</DOC>
<DOC>
<DOCNO> 85536 </DOCNO>
Asymptotic power-law tails of massive scalar fields in


  We investigate dominant late-time tail behaviors of massive scalar fields in
nearly extreme Reissner-Nordstr\"{o}m background. It is shown that the
oscillatory tail of the scalar fields has the decay rate of $t^{-5/6}$ at
asymptotically late times. The physical mechanism by which the asymptotic
$t^{-5/6}$ tail yields and the relation between the field mass and the time
scale when the tail begins to dominate, are discussed in terms of resonance
backscattering due to spacetime curvature.

</DOC>
<DOC>
<DOCNO> 119523 </DOCNO>
A New Model for the Width of the Broad Emission Lines in AGN: The Role


  We present a model which relates the Broad Emission Line Regions of AGN to
the accretion mechanism. Based on the Keplerian assumption for the high
velocity clouds of the gas responsible for the production of the Broad Emission
Lines, we identify that gas with an outflowing disk/coronal wind forms a
stabilized Shakura-Sunyaev accretion disk. We show that in the framework of
this picture the observed range of H-beta FWHM from Broad Line to Narrow Line
type 1 AGN, is well reproduced as a function of the accretion rate.

</DOC>
<DOC>
<DOCNO> 12963 </DOCNO>
Patterns of consumption in a discrete choice model with asymmetric


  We study the consumption behaviour of an asymmetric network of heterogeneous
agents in the framework of discrete choice models with stochastic decision
rules. We assume that the interactions among agents are uniquely specified by
their ``social distance'' and consumption is driven by peering, distinction and
aspiration effects. The utility of each agent is positively or negatively
affected by the choices of other agents and consumption is driven by peering,
imitation and distinction effects. The dynamical properties of the model are
explored, by numerical simulations, using three different evolution algorithms
with: parallel, sequential and random-sequential updating rules. We analyze the
long-time behaviour of the system which, given the asymmetric nature of the
interactions, can either converge into a fixed point or a periodic attractor.
We discuss the role of symmetric versus asymmetric contributions to the utility
function and also that of idiosyncratic preferences, costs and memory in the
consumption decision of the agents.

</DOC>
<DOC>
<DOCNO> 152064 </DOCNO>
Self-consistent renormalization group flow


  A self-consistent renormalization group flow equation for the scalar lambda
phi^4 theory is analyzed and compared with the local potential approximation.
The two prescriptions coincide in the sharp cutoff limit but differ with a
smooth cutoff. The dependence of the critical exponent nu on the smoothness
parameter and the field of expansion is explored. An optimization scheme based
on the minimum sensitivity principle is employed to ensure the most rapid
convergence of nu with the level of polynomial truncation.

</DOC>
<DOC>
<DOCNO> 67985 </DOCNO>
Neutrino Masses and Lepton-Quark Symmetries


  The recent discovery by SuperKamiokande of evidence for neutrino masses
requires the addition of at least seven new parameters to the Standard Model.
We discuss the general theoretical schemes which require their inclusion, and
point out how quark-lepton symmetries, either in the framework of Grand
Unification, or of string theories, can be used to determine them

</DOC>
<DOC>
<DOCNO> 169780 </DOCNO>
Single Atoms in an Optical Dipole Trap: Towards a Deterministic Source


  We describe a simple experimental technique which allows us to store a small
and deterministic number of neutral atoms in an optical dipole trap. The
desired atom number is prepared in a magneto-optical trap overlapped with a
single focused Nd:YAG laser beam. Dipole trap loading efficiency of 100 % and
storage times of about one minute have been achieved. We have also prepared
atoms in a certain hyperfine state and demonstrated the feasibility of a
state-selective detection via resonance fluorescence at the level of a few
neutral atoms. A spin relaxation time of the polarized sample of $4.2\pm 0.7$ s
has been measured. Possible applications are briefly discussed.

</DOC>
<DOC>
<DOCNO> 7700 </DOCNO>
Combined He-atom scattering and theoretical study of the low energy


  The surface phonon dispersion curves of commensurate Xe monolayers on Cu(111)
and incommensurate Xe monolayers on Cu(001) surfaces have been measured using
He atom scattering (HAS) time of flight (TOF) spectroscopy. The TOF spectra are
interpreted by combining quantum scattering calculations with the dynamical
matrix description of the surface vibrations. Both a vertically polarized
Einstein-like mode and another, acoustic-like mode of dominantly longitudinal
character, are identified. The latter mode is characterized by the presence and
absence of the zone center frequency gap in the commensurate and incommensurate
adlayers, respectively. The microscopic description of the TOF spectral
intensities is based on the extensive theoretical studies of the interplay of
the phonon dynamics, projectile-surface potentials, multi-quantum interference
and projectile recoil, and their effect on the HAS spectra. Both single and
multi-quantum spectral features observed over a wide range of He atom incident
energies and substrate temperatures are successfully explained by the theory.

</DOC>
<DOC>
<DOCNO> 122371 </DOCNO>
Optical Spectra of Dusty Starbursts


  This contribution presents the optical spectral properties of FIR-luminous
galaxies, whose distinctive feature is often the simultaneous presence in the
spectra of a strong $\rm H\delta$ line in absorption and of emission lines
(e(a) spectra). A discrepancy between the star formation rate estimated from
the FIR luminosity and that derived from the $\rm H\alpha$ luminosity persists
even after having corrected the $\rm H\alpha$ flux for dust according to the
observed Balmer decrement. It is shown that the e(a) spectrum can be reproduced
assuming a current starburst and dust extinction affecting the youngest stellar
populations much more than the older stars.

</DOC>
<DOC>
<DOCNO> 10623 </DOCNO>
Parametrization of Multiple Pathways in Proteins: Fast Folding versus


  Growing experimental evidence shows that proteins follow one or a few
distinct paths when folding. We propose in this paper a procedure to
parametrize these observed pathways, and from this parametrization construct
effective Hamiltonians for the proteins. We furthermore study the
denaturated-native transitions for a wide class of possible effective
Hamiltonians based on this scheme, and find that the sharpness (tightness) of
the transitions typically are close to their theoretical maximum and thus in
quantitative accordance with the sharp folding transition observed for single
domain proteins. Finally we demonstrate that realistic folding times are
typical for the proposed class of Hamiltonians, and we discuss the implication
of the predicted entropy barriers on the temperature dependence of the folding
times.

</DOC>
<DOC>
<DOCNO> 116285 </DOCNO>
The preliminary results of fast neutron flux measurements in the DULB


  One of the main sources of a background in underground physics experiments
(such as the investigation of solar neutrino flux, neutrino oscillations,
neutrinoless double beta decay, and the search for annual and daily Cold Dark
Matter particle flux modulation) are fast neutrons originating from the
surrounding rocks. The measurements of fast neutron flux in the new DULB
Laboratory situated at a depth of 4900 m w.e. in the Baksan Neutrino
Observatory have been performed. The relative neutron shielding properties of
several commonly available natural materials were investigated too. The
preliminary results obtained with a high-sensitive fast neutron spectrometer at
the level of sensitivity of about 10^(-7) neutron/ (cm^2 sec) are presented and
discussed.

</DOC>
<DOC>
<DOCNO> 101507 </DOCNO>
Factorization of the Universal R-matrix for $U_q(\hat{sl}_2)$


  The factorization of the universal R-matrix corresponding to so called
Drinfeld Hopf structure is described on the example of quantum affine algebra
$U_q(\hat{sl}_2)$. As a result of factorization procedure we deduce certain
differential equations on the factors of the universal ${\cal R}$-matrix, which
allow to construct uniquely these factors in the integral form.

</DOC>
<DOC>
<DOCNO> 11453 </DOCNO>
Control of Decoherence and Correlation in Single Quantum Dissipative


  A single quantum dissipative oscillator described by the Lindblad equation
serves as a model for a nanosystem. This model is solved exactly by using the
ambiguity function. The solution shows the features of decoherence (spatial
extent of quantum behavior), correlation (spatial scale over which the system
localizes to its physical dimensions), and mixing (mixed- state spatial
correlation). A new relation between these length scales is obtained here. By
varying the parameters contained in the Lindblad equation, it is shown that
decoherence and correlation can be controlled. We indicate possible
interpretation of the Lindblad parameters in the context of experiments using
engineered reservoirs.

</DOC>
<DOC>
<DOCNO> 11829 </DOCNO>
Nonlinearity of Acoustic Effects and High-Frequency Electrical


  The absorption coefficient for surface acoustic wave $\Gamma$ and variation
in the wave velocity $\Delta V/V$ were measured in GaAs/AlGaAs
heterostructures; the above quantities are related to interaction of the wave
with two-dimensional electron gas and depend nonlinearly on the power of the
wave. Measurements were performed under conditions of the integer quantum Hall
effect (IQHE), in which case the two-dimensional electron gas was localized in
a random fluctuation potential of impurities. The dependences of the components
$\sigma_1(E)$ and $\sigma_2(E)$ of high-frequency conductivity $\sigma=\sigma_1
- i\sigma_2$ on the electric field of the surface wave were determined. In the
range of the conductivity obeying the Arrhenius law ($\sigma_1 \gg \sigma_2$),
the results obtained are interpreted in terms of the Shklovskii theory of
nonlinear percolation-based conductivity, which makes it possible to estimate
the magnitude of the fluctuation potential of impurities. The dependences
$\sigma_1(E)$ and $\sigma_2(E)$ in the range of high-frequency hopping
electrical conductivity, in which case ($\sigma_1 \ll \sigma_2$) and the theory
of nonlinearities has not been yet developed, are reported.

</DOC>
<DOC>
<DOCNO> 85516 </DOCNO>
Ultralocal Fields and their Relevance for Reparametrization Invariant


  Reparametrization invariant theories have a vanishing Hamiltonian and enforce
their dynamics through a constraint. We specifically choose the Dirac procedure
of quantization before the introduction of constraints. Consequently, for field
theories, and prior to the introduction of any constraints, it is argued that
the original field operator representation should be ultralocal in order to
remain totally unbiased toward those field correlations that will be imposed by
the constraints. It is shown that relativistic free and interacting theories
can be completely recovered starting from ultralocal representations followed
by a careful enforcement of the appropriate constraints. In so doing all
unnecessary features of the original ultralocal representation disappear.
  The present discussion is germane to a recent theory of affine quantum
gravity in which ultralocal field representations have been invoked before the
imposition of constraints.

</DOC>
<DOC>
<DOCNO> 69248 </DOCNO>
Low-energy Limits on the Antisymmetric Tensor Field Background on the


  A non-vanishing vacuum expectation value for an antisymmetric tensor field
leads to the violation of Lorentz invariance on the brane. This violation is
controlled by the $\theta_{\mu \nu}$ parameter, which has a dimension of
inverse mass squared. We assume that the zeroth order term in theta-expansion
represents the Standard Model and study the effects induced by linear terms in
theta_{\mu\nu}. Low-energy precision experiments place the limit on the
possible size of this background at the level of $1/\sqrt{\theta} > 5 \times
10^{14}$ GeV. This poses certain difficulty for the TeV-range string scale
models, in which the antisymmetric field has to acquire a relatively large mass
to ensure that $\theta_{\mu \nu}=0$ and avoid cosmological moduli problem.

</DOC>
<DOC>
<DOCNO> 10286 </DOCNO>
CuSiO_3 : a quasi - one - dimensional S=1/2 antiferromagnetic chain


  CuSiO_3, isotypic to the spin - Peierls compound CuGeO_3, was discovered
recently as a metastable decomposition product of the silicate mineral
dioptase, Cu_6Si_6O_{18}\cdot6H_2O. We investigated the physical properties of
CuSiO_3 using susceptibility, magnetization and specific heat measurements on
powder samples. The magnetic susceptibility \chi(T) is reproduced very well
above T = 8 K by theoretical calculations for an S=1/2 antiferromagnetic
Heisenberg linear chain without frustration (\alpha = 0) and a nearest -
neighbor exchange coupling constant of J/k_{B} = 21 K, much weaker than in
CuGeO_3. Below 8 K the susceptibility exhibits a substantial drop. This feature
is identified as a second - order phase transition at T_{0} = 7.9 K by specific
heat measurements. The influence of magnetic fields on T_{0} is weak, and ac -
magnetization measurements give strong evidence for a spin - flop - phase at
\mu_0H_{SF} ~ 3 T. The origin of the magnetic phase transition at T_{0} = 7.9 K
is discussed in the context of long - range antiferromagnetic order (AF) versus
spin - Peierls(SP)order. Susceptibility and specific heat results support the
AF ordered ground state. Additional temperature dependent ^{63,65}Cu nuclear
quadrupole resonance experiments have been carried out to probe the Cu^{2+}
electronic state and the spin dynamics in CuSiO_3.

</DOC>
<DOC>
<DOCNO> 118871 </DOCNO>
Large scale star formation in galaxies. I. The spirals NGC 7217, NGC


  We present multiband photometric observations of three spiral galaxies
selected in a sample suited for the study of young stellar groupings and their
relationship with the parent galaxy and the galactic environment. Star forming
regions have been identified using an objective technique based on a
multivariate statistical analysis. Maps of young star groupings are given for
each galaxy. The luminosity functions of the young star group populations show
a remarkable similarity with a slope in the range -1.52 to -1.33 range. The
size distributions peak around the classical 100pc value of the Local Group
associations for two out of the three galaxies. NGC 1058 shows smaller
associations (peak at about 50pc). The total number of young groups per unit B
absolute luminosity of the galaxy is significantly greater in UGC 12732. The
activity of star formation is in all three galaxies clearly stronger in the
central regions.

</DOC>
<DOC>
<DOCNO> 151692 </DOCNO>
The phases of 2D NCOS


  We study the phases of the 1+1 dimensional Non-Commutative Open String theory
on a circle. We find that the length scale of non-commutativity increases at
strong coupling, the coupling in turn being dressed by a power of D-string
charge. The system is stringy at around this length scale, with dynamics
involving an interplay between the open and wrapped closed strings sectors.
Above this energy scale and at strong coupling, and below it at weak coupling,
the system acquires a less stringy character. The near horizon geometry of the
configuration exhibits several intriguing features, such as a flip in the
dilaton field and the curvature scale, reflecting UV-IR mixing in
non-commutative dynamics. Two special points in the parameter measuring the
size of the circle are also identified.

</DOC>
<DOC>
<DOCNO> 8530 </DOCNO>
The plasma-insulator transition of spin-polarized Hydrogen


  A mixed classical-quantum density functional theory is used to calculate pair
correlations and the free energy of a spin-polarized Hydrogen plasma. A
transition to an atomic insulator phase is estimated to occur around r_s=2.5 at
T=10^4K, and a pressure $P\approx0.5Mbar$. Spin polarization is imposed to
prevent the formation of H_2 molecules.

</DOC>
<DOC>
<DOCNO> 123166 </DOCNO>
Formation and evolution of E+A galaxies in dusty starburst galaxies


  The formation and evolution of the ``E+A'' (also named ``k+a'' and ``a+k''
types by Dressler et al. 1999) galaxies found in significant numbers in the
cores of intermediate redshift clusters has been extensively discussed by many
authors. In this paper, we model the spectral, dynamical and morphological
evolution of a prime candidate for producing this spectral signature: a dusty
starburst associated with a major galaxy merger. We show that as this system
evolves dynamically, its spectral type changes from and ``e(a)'' type
(exhibiting strong H$\delta$ absorption and modest [OII] emission -- the
identifying features of local dusty starburst galaxies) to a k+a type and then
finally to a passive ``k'' type. This result shows that galaxies with an e(a)
spectral type can be precursors to the k+a systems and that dynamical evolution
greatly controls the spectral evolution in these merger cases. Our simulations
also show that a merger with very high infrared luminosity ($L_{\rm IR}$ $>$
$10^{11}$ $L_{\odot}$) is more likely to show an e(a) spectrum, which implies
that spectral types can be correlated with infrared fluxes in dusty starburst
galaxies. Based on these results, we discuss the origin of the evolution of
k+a/a+k galaxies in distant clusters and the role merging is likely to have.

</DOC>
<DOC>
<DOCNO> 84311 </DOCNO>
Pad\'e approximants for truncated post-Newtonian neutron star models


  Pad\'e approximants to truncated post-Newtonian neutron star models are
constructed. The Pad\'e models converge faster to the general relativistic (GR)
solution than the truncated post-Newtonian ones. The evolution of initial data
using the Pad\'e models approximates better the evolution of full GR initial
data than the truncated Taylor models. In the absence of full GR initial data
(e.g., for neutron star binaries or black hole binary systems), Pad\'e initial
data could be a better option than the straightforward truncated post-Newtonian
(Taylor) initial data.

</DOC>
<DOC>
<DOCNO> 122027 </DOCNO>
FUSE Observations of the hottest DA white dwarfs


  We report early FUSE observations of the very hot DA white dwarfs PG1342+444
and REJ0558-371. Detection of photospheric absorption lines allows us to
estimate the abundances of C, O, Si, P, S and Fe, the first measurements
reported for DA stars at such high temperatures. Values of Teff and log g
determined for PG1342+444 from the Lyman line series disagree with the results
of the standard Balmer line analysis, an issue that requires further
investigation.

</DOC>
<DOC>
<DOCNO> 118634 </DOCNO>
A Cluster of Black Holes at the Galactic Center


  If the stellar population of the bulge contains black holes formed in the
final core collapse of ordinary stars with M \ga 30 M_{\odot}, then about
25,000 stellar mass black holes should have migrated by dynamical friction into
the central parsec of the Milky Way, forming a black hole cluster around the
central supermassive black hole. These black holes can be captured by the
central black hole when they randomly reach a highly eccentric orbit due to
relaxation, either by direct capture (when their Newtonian peribothron is less
than 4 Schwarzschild radii), or after losing orbital energy through
gravitational waves. The overall depletion timescale is ~ 30 Gyr, so most of
the 25,000 black holes remain in the central cluster today. The presence of
this black hole cluster would have several observable consequences. First, the
low-mass, old stellar population should have been expelled from the region
occupied by the black hole cluster due to relaxation, implying a core in the
profile of solar-mass red giants with a radius of ~ 2 pc (i.e., 1'). The
observed central density cusp (which has a core radius of only a few arc
seconds) should be composed primarily of young (\la 1 Gyr) stars. Second,
flares from stars being captured by supermassive black holes in other galaxies
should be rarer than usually expected because the older stars will have been
expelled from the central regions by the black hole clusters of those galaxies.
Third, the young (\la 2 Gyr) stars found at distances ~ 3 - 10 pc from the
Galactic center should be preferentially on highly eccentric orbits. Fourth, if
future high-resolution $K$-band images reveal sources microlensed by the Milky
Way's central black hole, then the cluster black holes could give rise to
secondary (``planet-like'') perturbations on the main event.

</DOC>
<DOC>
<DOCNO> 170037 </DOCNO>
The One, the Many, and the Quantum


  The problem of understanding quantum mechanics is in large measure the
problem of finding appropriate ways of thinking about the spatial and temporal
aspects of the physical world. The standard, substantival, set-theoretic
conception of space is inconsistent with quantum mechanics, and so is the
doctrine of local realism, the principle of local causality, and the
mathematical physicist's golden calf, determinism. The said problem is made
intractable by our obtruding onto the physical world a theoretical framework
that is more detailed than the physical world. This framework portraits space
and time as infinitely and intrinsically differentiated, whereas the physical
world is only finitely differentiated spacewise and timewise, namely to the
extent that spatiotemporal relations and distinctions are warranted by facts.
This has the following consequences: (i) The contingent properties of the
physical world, including the times at which they are possessed, are indefinite
and extrinsic. (ii) We cannot think of reality as being built "from the bottom
up", out of locally instantiated physical properties. Instead we must conceive
of the physical world as being built "from the top down": By entering into a
multitude of spatial relations with itself, "existence itself" takes on both
the aspect of a spatially differentiated world and the aspect of a multiplicity
of formless relata, the fundamental particles. At the root of our
interpretational difficulties is the "cookie cutter paradigm", according to
which the world's synchronic multiplicity is founded on the introduction of
surfaces that carve up space in the manner of three-dimensional cookie cutters.
The neurophysiological underpinnings of this insidious notion are discussed.

</DOC>
<DOC>
<DOCNO> 68111 </DOCNO>
Precision Mass Determination of the Higgs Boson at Photon-Photon


  We demonstrate a measurement of the Higgs boson mass by the method of energy
scanning at photon-photon colliders, using the high energy edge of the photon
spectrum. With an integrated luminosity of 50 $\rm{fb^{-1}}$ it is possible to
measure the standard model Higgs mass to within 110 MeV in photon-photon
collisions for m_h=100 GeV. As for the total width of the Higgs boson, the
statistical error $\Delta\Gamma_h/\Gamma_{h \rm{SM}}=0.06$ is expected for
m_h=100 GeV, if both $\Gamma(h\to\gamma\gamma)$ and $\Gamma(h\to b\bar{b})$ are
fixed at the predicted standard model value.

</DOC>
<DOC>
<DOCNO> 9934 </DOCNO>
Impurity Scattering from $\delta$-layers in Giant Magnetoresistance


  The properties of the archetypal Co/Cu giant magnetoresistance (GMR)
spin-valve structure have been modified by the insertion of very thin
(sub-monolayer) $\delta$-layers of various elements at different points within
the Co layers, and at the Co/Cu interface. Different effects are observed
depending on the nature of the impurity, its position within the periodic
table, and its location within the spin-valve. The GMR can be strongly enhanced
or suppressed for various specific combinations of these parameters, giving
insight into the microscopic mechanisms giving rise to the GMR.

</DOC>
<DOC>
<DOCNO> 8786 </DOCNO>
Quantum Phase Transitions of a Square-Lattice Heisenberg Antiferromagnet


  We study the zero-temperature phase diagram and the low-lying excitations of
a square-lattice spin-half Heisenberg antiferromagnet with two types of
regularly distributed nearest-neighbour exchange bonds (J>0 (antiferromagnetic)
and J'>0, J'<0) using the coupled cluster method (CCM) for high orders of
approximation (up to LSUB8). We use a Neel model state as well as a helical
model state as a starting point for the CCM calculations. We find a
second-order transition from a phase with Neel order to a finite-gap quantum
disordered phase for sufficiently large antiferromagnetic exchange constants
J'>0. For frustrating ferromagnetic couplings J'<0 we find indications that
quantum fluctuations favour a first-order phase transition from the Neel order
to a quantum helical state, by contrast with the corresponding second-order
transition in the corresponding classical model. The results are compared to
those of exact diagonalizations of finite systems (up to 32 sites) and those of
spin-wave and variational calculations. The CCM results agree well with the
exact diagonalization data over the whole range of the parameters. The special
case of J'=0, which is equivalent to the honeycomb lattice, is treated more
closely.

</DOC>
<DOC>
<DOCNO> 99589 </DOCNO>
Differential 3-knots in 5-space with and without self intersections


  Regular homotopy classes of immersions of a 3-sphere in 5-space constitute an
infinite cyclic group. The classes containing embeddings form a subgroup of
index 24. The obstruction for a generic immersion to be regularly homotopic to
an embedding is described in terms of geometric invariants of its self
intersection. Geometric properties of self intersections are used to construct
two invariants J and St of generic immersions which are analogous to Arnold's
invariants of plane curves. We prove that J and St are independent first order
invariants and that any first order invariant is a linear combination of these.
  As by-products, some invariants of immersions of 3-spheres in 4-space are
obtained. Using them, we find restrictions on the topology of self
intersections.

</DOC>
<DOC>
<DOCNO> 116647 </DOCNO>
Bessel Beams


  Scalar Bessel beams are derived both via the wave equation and via
diffraction theory. While such beams have a group velocity that exceeds the
speed of light, this is a manifestation of the "scissors paradox" of special
relativty. The signal velocity of a modulated Bessel beam is less than the
speed of light. Forms of Bessel beams that satisfy Maxwell's equations are also
given.

</DOC>
<DOC>
<DOCNO> 170726 </DOCNO>
A continuum local hidden variable model for the EPR experiment


  The paper is withdrawn by the author, due to the fact that in Larsson's
Phys.Lett. A256 (1999) 245-252 (quant-ph/9901074) a similar model was published
with even higher efficiency.

</DOC>
<DOC>
<DOCNO> 85577 </DOCNO>
Families of exact solutions of a 2D gravity model minimally coupled to


  Three families of exact solutions for 2-dimensional gravity minimally coupled
to electrodynamics are obtained in the context of ${\cal R}=T$ theory. It is
shown, by supersymmetric formalism of quantum mechanics, that the quantum
dynamics of a neutral bosonic particle on static backgrounds with both varying
curvature and electric field is exactly solvable.

</DOC>
<DOC>
<DOCNO> 9163 </DOCNO>
Resistance Jumps and Hysteresis in Ferromagnetic Wires


  A phenomenological approach based on the principle of minimum heat generation
is proposed for understanding experiments for metallic wires with a
ferromagnetic domain wall controlled by a magnetic field. This approach
elucidates the origin of negative jump and of hysteresis in the
magnetoresistance experiments. To justify our approach, we computed the
transmission probability of a single electron through a wire. Under certain
conditions, the presence of a domain wall enhances the transmission through an
impurity potential. Combining this result with the principle of minimum heat
generation explains the counterintuitive negative resistance jump.

</DOC>
<DOC>
<DOCNO> 13986 </DOCNO>
New Origin For Spin Current And Current-Induced Spin Precession In


  In metallic ferromagnets, an electric current is accompanied by a flux of
angula r momentum, also called spin current. In multilayers, spatial variations
of the spin current correspond to drive torques exerted on a magnetic layer.
These torq ues result in spin precession above a certain current threshold. The
usual kind of spin current is associated with translation of the spin-up and
spin-down Ferm i surfaces in momentum space. We discuss a different kind of
spin current, assoc iated with expansion and contraction of the Fermi surfaces.
It is more nonlocal in nature, and may exist even in locations where the
electrical current density is zero. It is larger than the usual spin current,
in a ratio of 10 or 100, and is dominant in most cases. The new spin current is
proportional to the differenc e Delta-mu = 0.001 eV between spin-up and
spin-down Fermi levels, averaged over the entire Fermi surface. Conduction
processes, spin relaxation, and spin-wave emission in the multilayer can be
described by an equivalent electrical circuit resembling an unbalanced dc
Wheatstone bridge. And Delta-mu corresponds to the output voltage of the
bridge.

</DOC>
<DOC>
<DOCNO> 11240 </DOCNO>
Library Design in Combinatorial Chemistry by Monte Carlo Methods


  Strategies for searching the space of variables in combinatorial chemistry
experiments are presented, and a random energy model of combinatorial chemistry
experiments is introduced. The search strategies, derived by analogy with the
computer modeling technique of Monte Carlo, effectively search the variable
space even in combinatorial chemistry experiments of modest size. Efficient
implementations of the library design and redesign strategies are feasible with
current experimental capabilities.

</DOC>
<DOC>
<DOCNO> 84974 </DOCNO>
Some Higher Dimensional Vacuum Solutions


  We study an even dimensional manifold with a pseudo-Riemannian metric with
arbitrary signature and arbitrary dimensions. We consider the Ricci flat
equations and present a procedure to construct solutions to some higher (even)
dimensional Ricci flat field equations from the four diemnsional Ricci flat
metrics. When the four dimensional Ricci flat geometry correponds to a
colliding gravitational vacuum spacetime our approach provides an exact
solution to the vacuum Einstein field equations for colliding graviational
plane waves in an (arbitrary) even dimensional spacetime. We give explicitly
higher dimensional Szekeres metrics and study their singularity behaviors.

</DOC>
<DOC>
<DOCNO> 119536 </DOCNO>
Properties of Warm absorbers in Narrow-Line Seyfert 1 galaxies


  We present a study of the X-ray properties of several NLS1 galaxies, focusing
on their warm absorbers. In the first part, we discuss properties of dusty and
dust-free warm absorbers in NLS1s, and study their potential contribution to
high-ionization optical iron lines. In the second part, we summarize our work
on the exceptional spectral variability of the NLS1 galaxy RX J0134.3-4258
(from Gamma about -4.4 in the ROSAT all-sky survey observation, to about -2.2
in our subsequent pointed observation).

</DOC>
<DOC>
<DOCNO> 68463 </DOCNO>
Non-Minimal and Non-Universal Supersymmetry


  I motivate and discuss non-minimal and non-universal models of supersymmetry
and supergravity consistent with string unification at $10^{16}$ GeV.

</DOC>
<DOC>
<DOCNO> 11724 </DOCNO>
Implications of SU(2) symmetry on the dynamics of population difference


  We present an exact many body solution for the dynamics of the population
difference $N_2-N_1$ induced by an rf-field in the two-component atomic cloud
characterized by equal scattering lengths. This situation is very close to the
actual JILA experiments with the two-component $^{87}$Rb vapor. We show that no
intrinsic decoherence exists for $N_2-N_1$, provided the exact SU(2) symmetry
holds. This contrasts with finite dissipation of the normal modes even in the
presence of the SU(2) symmetry. The intrinsic decoherence for \$N_2-N_1$ may
occur as long as deviations from the exact SU(2) symmetry are taken into
account. Such decoherence, however, should be characterized by very long times
governed by the smallness of the deviations from the symmetry. We suggest
testing the evolution of $N_2-N_1$ by conducting echo-type experiments.

</DOC>
<DOC>
<DOCNO> 85501 </DOCNO>
Chaos in FRW cosmology with various types of a scalar field potential


  The results on chaos in FRW cosmology with a massive scalar field are
extended to another scalar field potential. It is shown that for sufficiently
steep potentials the chaos disappears. A simple and rather accurate analytical
criterion for the chaos to disappear is given. On the contrary, for gently
sloping potentials the transition to a strong chaotic regime can occur. Two
examples, concerning asymptotically flat and Damour-Mukhanov potentials are
given.

</DOC>
<DOC>
<DOCNO> 11130 </DOCNO>
Quenching and Annealing in the Minority Game


  We report the occurrence of quenching and annealing in a version of the
Minority Game (MG) in which the winning option is to join a given fraction of
the population that is a free, external parameter. We compare this to the
different dynamics of the Bar Attendance Model (BAM) where the updating of the
attendance strategy makes use of all available information about the system and
quenching does not occur. We provide an annealing schedule by which the
quenched configuration of the MG reaches equilibrium and coincides with the one
obtained with the BAM

</DOC>
<DOC>
<DOCNO> 99681 </DOCNO>
Secondary Characteristic Classes and Cyclic Cohomology of Hopf Algebras


  We give a construction of cyclic cocycles representing the equivariant
characteristic classes of equivariant bundles.
 Our formulas generalize Connes' Godbillon-Vey cyclic cocycle. An essential
tool of our construction is Connes-Moscovici's theory of cyclic cohomology of
Hopf algebras.

</DOC>
<DOC>
<DOCNO> 169702 </DOCNO>
Towards the elusive Efimov state of the ^4He_3 molecule through a new


  Excited states and excitation energies of weakly bound systems, e.g. atomic
few-body systems and clusters, are difficult to study experimentally. For this
purpose we propose a new and very general atom-optical method which is based on
inelastic diffraction from transmission gratings. The technique is applicable
to the recently found helium trimer molecule ^4He_3, allowing for the first
time an investigation of the possible existence of an excited trimer state and
determination of its excitation energy. This would be of fundamental importance
for the famous Efimov effect.

</DOC>
<DOC>
<DOCNO> 70653 </DOCNO>
A critical look at catastrophe risk assessments


  Recent papers by Busza et al. (BJSW) and Dar et al. (DDH) argue that
astrophysical data can be used to establish bounds on the risk of a catastrophe
in forthcoming collider experiments. The safety case set out by BJSW does not
rely on these bounds, but on theoretical arguments, which BJSW find
sufficiently compelling. However, DDH and other commentators (initially
including BJSW) have suggested that the astrophysical bounds alone do give
sufficient reassurance. This seems unsupportable when the bounds are expressed
in terms of expected cost. For example, DDH's main bound, p_catastrophe < 2
\times 10^{-8}, implies only that the expectation value of the number of deaths
is bounded by 120. We thus reappraise the DDH and BJSW risk bounds by comparing
risk policy in other areas. We find that requiring a catastrophe risk of no
higher than 10^{-15} per year is necessary to be consistent with established
policy for risk optimisation from radiation hazards, even if highly risk
tolerant assumptions are made. A respectable case can be made for requiring a
bound many orders of magnitude smaller. We conclude that the costs of small
risks of catastrophe have generally been significantly underestimated in the
physics literature. This conclusion does not affect the theoretical arguments
against the possibility of catastrophe in the experiments considered. It does,
however, suggest more careful consideration of the degree of confidence that
can reasonably be placed in those arguments.

</DOC>
<DOC>
<DOCNO> 12506 </DOCNO>
Spin Injection from Ferromagnetic Metals into Gallium Nitride


  The injection of spin polarized electrons from ferromagnetic metals (Fe and
Co) into gallium nitride (GaN) via scanning tunneling microscopy (STM) is
demonstrated. Electrons from STM tips are injected into the semiconductor. Net
circular polarization of the emitted light is observed, which changes sign on
reversal of the magnetization of the tip. The polarization is found to be in
qualitative agreement with that expected from considerations based on the
splitting of the valence bands due to spin-orbit coupling and the crystal field
splitting corresponding to the wurtzite structure, and the magnitude of the
spin polarization from the ferromagnetic metal. We find a lower bound for the
spin injection efficiency of 25%, corresponding to a net spin polarization in
the semiconductor of 10%. This is the largest reported value for a room
temperature measurement of spin injection into semiconductors in air.

</DOC>
<DOC>
<DOCNO> 117181 </DOCNO>
Relativistic angle-changes and frequency-changes


  We generate a set of "relativistic" predictions for the relationship between
viewing angle and apparent frequency, for each of three different
non-transverse shift equations. We find that a detector aimed transversely (in
the lab frame) at a moving object should report a redshift effect with two out
of the three equations.

</DOC>
<DOC>
<DOCNO> 40041 </DOCNO>
Optical production and detection of dark matter candidates


  The PVLAS collaboration is at present running, at the Laboratori Nazionali di
Legnaro of I.N.F.N., Padova, Italy, a very sensitive optical ellipsometer
capable of measuring the small rotations or ellipticities which can be acquired
by a linearly polarized laser beam propagating in vacuum through a transverse
magnetic feld (vacuum magnetic birefringence). The apparatus will also be able
to set new limits on mass and coupling constant of light scalar/pseudoscalar
particles coupling to two photons by both producing and detecting the
hypothetical particles. The axion, introduced to explain parity conservation in
strong interactions, is an example of this class of particles, all of which are
considered possible dark matter candidates. The PVLAS apparatus consists of a
very high finesse (> 140000), 6.4 m long, Fabry-Perot cavity immersed in an
intense dipolar magnetic field (~6.5 T). A linearly polarized laser beam is
frequency locked to the cavity and analysed, using a heterodyne technique, for
rotation and/or ellipticity acquired within the magnetic field.

</DOC>
<DOC>
<DOCNO> 101076 </DOCNO>
Mathematical Formalism for Isothermal Linear Irreversibility


  We prove the equivalence among symmetricity, time reversibility, and zero
entropy production of the stationary solutions of linear stochastic
differential equations. A sufficient and necessary reversibility condition
expressed in terms of the coefficients of the equations is given. The existence
of a linear stationary irreversible process is established. Concerning
reversibility, we show that there is a contradistinction between any
1-dimensional stationary Gaussian process and stationary Gaussian process of
dimension $n>1$. A concrete criterion for differentiating stationarity and
sweeping behavior is also obtained. The mathematical result is a natural
generalization of Einstein's fluctuation-dissipation relation, and provides a
rigorous basis for the isothermal irreversibility in a linear regime which is
the basis for applying Onsager's theory to macromolecules in aqueous solution.

</DOC>
<DOC>
<DOCNO> 72323 </DOCNO>
Type I Superconductivity upon Monopole Condensation in Seiberg-Witten


  We study the confinement scenario in N=2 supersymmetric SU(2) gauge theory
near the monopole point upon breaking of N=2 supersymmetry by the adjoint
matter mass term. We confirm claims made previously that the
Abrikosov-Nielsen-Olesen string near the monopole point fails to be a BPS state
once next-to-leading corrections in the adjoint mass parameter taken into
account. Our results shows that type I superconductivity arises upon monopole
condensation. This conclusion allows us to make qualitative predictions on the
structure of the hadron mass spectrum near the monopole point.

</DOC>
<DOC>
<DOCNO> 8535 </DOCNO>
Continuous weak measurement of quantum coherent oscillations


  We consider the problem of continuous quantum measurement of coherent
oscillations between two quantum states of an individual two-state system. It
is shown that the interplay between the information acquisition and the
backaction dephasing of the oscillations by the detector imposes a fundamental
limit, equal to 4, on the signal-to-noise ratio of the measurement. The limit
is universal, e.g., independent of the coupling strength between the detector
and system, and results from the tendency of quantum measurement to localize
the system in one of the measured eigenstates.

</DOC>
<DOC>
<DOCNO> 102607 </DOCNO>
Fredholm Properties of Elliptic Operators on $\R^n$


  We study the Fredholm properties of a general class of elliptic differential
operators on $\R^n$. These results are expressed in terms of a class of
weighted function spaces, which can be locally modeled on a wide variety of
standard function spaces, and a related spectral pencil problem on the sphere,
which is defined in terms of the asymptotic behaviour of the coefficients of
the original operator.

</DOC>
<DOC>
<DOCNO> 67723 </DOCNO>
Relic neutralinos: update on neutralino-nucleon scalar cross-section


  We discuss the effect induced on the neutralino-nucleon scalar cross-section
by the present uncertainties in the values of the quark masses and of the quark
scalar densities in the nucleon. We examine the implications of this aspect on
the determination of the neutralino cosmological properties, as derived from
measurements of WIMP direct detection. We show that, within current theoretical
uncertainties, the DAMA annual modulation data are compatible with a neutralino
as a major dark matter component, to an extent which is even larger than the
one previously derived.

</DOC>
<DOC>
<DOCNO> 85597 </DOCNO>
Nonconformal Scalar Field in a Homogeneous Isotropic Space and the


  The diagonalization of the metrical Hamiltonian of a scalar field with an
arbitrary coupling with a curvature in N-dimensional homogeneous isotropic
space is performed. The energy spectrum of the corresponding quasiparticles is
obtained. The energies of the quasiparticles corresponding to the diagonal form
of the canonical Hamiltonian are calculated. The modified energy-momentum
tensor with the following properties is constructed. It coincides with the
metrical energy-momentum tensor for conformal scalar field. Under its
diagonalization the energies of relevant particles of a nonconformal field
coincide to the oscillator frequencies and the density of such particles
created in a nonstationary metric is finite. It is shown that the Hamiltonian
calculated with the modified energy-momentum tensor can be constructed as a
canonical Hamiltonian under the special choice of variables.

</DOC>
<DOC>
<DOCNO> 9913 </DOCNO>
Soundwave Anomalies in SrCu_{2}(BO_{3})_{2}


  The temperature and high magnetic field dependence of the longitudinal
soundwave mode c_{11} in the two dimensional dimer system SrCu_{2}(BO_{3})_{2}
is presented. c_{11}(T) shows anomalies due to strong interdimer spin-strain
coupling. We can quantitatively interpret the temperature dependence of
c_{11}(T) together with the magnetic susceptibility $\chi_{m}(T)$ with a
molecular field approximation of coupled dimer triplets. The sound velocity up
to 50T shows very sharp softening between the magnetization plateaus at low
temperature. We argue that these pronounced effects arise from a resonant
interaction between the phonons and the magnetic excitations which show
softening between the plateaus.

</DOC>
<DOC>
<DOCNO> 69133 </DOCNO>
D^0 - D^0-bar Oscillations as a Probe of Quark-Hadron Duality


  It is usually argued that the Standard Model predicts slow D^0-\bar D^0
oscillations with \Delta M_D, \Delta \Gamma_D < 10^{-3}*\Gamma_D$ and that New
Physics can reveal itself through \Delta M_D exceeding 10^{-3}*\Gamma_D. It is
believed that the bulk of the effect is due to long distance dynamics that
cannot be described at the quark level. We point out that in general the OPE
yields soft GIM suppression scaling only like (m_s/\mu_{hadr})^2 and even like
m_s/\mu_{hadr} rather than m_s^4/m_c^4 of the simple quark box diagram. Such
contributions can actually yield \Delta M_D, \Delta \Gamma_D \sim
O(10^{-3})*\Gamma_D without invoking additional long distance effects. They are
reasonably suppressed as long as the OPE and local duality are qualitatively
applicable in the 1/m_c expansion. We stress the importance of improving the
sensitivity on \Delta \Gamma_D as well as \Delta M_D in a dedicated fashion as
a laboratory for analyzing the onset of quark-hadron duality and comment on the
recent preliminary study on \Delta \Gamma_D by the FOCUS group.

</DOC>
<DOC>
<DOCNO> 12911 </DOCNO>
Flux tubes, visons, and vortices in spin-charge separated


  The idea of spin-charge separation in cuprate superconductors has been
recently energized by Senthil and Fisher who formulated a Z_2 gauge theory and,
within its context, proposed a ``vison detection'' experiment as a test for
topological order in a sample with multiply connected geometry. Here we show
that the same experiment can be performed to test for the spin-charge
separation in U(1) [but not in SU(2)] theory and argue that vortex core
spectroscopy can in fact distinguish between the different symmetries of the
fictitious gauge field.

</DOC>
<DOC>
<DOCNO> 151091 </DOCNO>
Supergravity flows and D-brane stability


  We investigate the correspondence between existence/stability of BPS states
in type II string theory compactified on a Calabi-Yau manifold and BPS
solutions of four dimensional N=2 supergravity. Some paradoxes emerge, and we
propose a resolution by considering composite configurations. This in turn
gives a smooth effective field theory description of decay at marginal
stability. We also discuss the connection with 3-pronged strings, the Joyce
transition of special Lagrangian submanifolds, and Pi-stability.

</DOC>
<DOC>
<DOCNO> 100239 </DOCNO>
Groupoids and the integration of Lie algebroids


  We show that a Lie algebroid on a stratified manifold is integrable if, and
only if, its restriction to each strata is integrable. These results allow us
to construct a large class of algebras of pseudodifferential operators.

</DOC>
<DOC>
<DOCNO> 118464 </DOCNO>
Simultaneous optical polarimetry and X-ray data of the near synchronous


  We present simultaneous optical polarimetry and X-ray data of the near
synchronous polar RX J2115-5840. We model the polarisation data using the
Stokes imaging technique of Potter et al. We find that the data are best
modelled using a relatively high binary inclination and a small angle between
the magnetic and spin axes. We find that for all spin-orbit beat phases, a
significant proportion of the accretion flow is directed onto the lower
hemisphere of the white dwarf, producing negative circular polarisation. Only
for a small fraction of the beat cycle is a proportion of the flow directed
onto the upper hemisphere. However, the accretion flow never occurs near the
upper magnetic pole, whatever the orientation of the magnetic poles. This
indicates the presence of a non-dipole field with the field strength at the
upper pole significantly higher. We find that the brightest parts of the hard
X-ray emitting region and the cyclotron region are closely coincident.

</DOC>
<DOC>
<DOCNO> 71836 </DOCNO>
Hybrid Inflation and Supergravity


  Hybrid inflation is a natural scenario in the absence of supersymmetry. In
the context of supergravity, however, it has to face the naturalness problems
of the initial conditions and of the adequate suppression of the inflaton mass.
Both can be successfully addressed in a class of models involving Kaehler
potentials associated with products of SU(1,1)/U(1) Kaehler manifolds and
"decoupled" fields acquiring large vacuum expectation values through D-terms.

</DOC>
<DOC>
<DOCNO> 84746 </DOCNO>
A critical-density closed Universe in Brans-Dicke theory


  In a Brans-Dicke (BD) cosmological model, the energy density associated with
some scalar field decreases as $\displaystyle a^{{-2}(\frac{\omega_{o}+
{\frac12}%}{\omega_{o}+1})} $ with the scale factor $a(t)$ of the Universe,
giving a matter with an Equation of state $\displaystyle
p=-{1/3}(\frac{2+\omega_{o}}{1+\omega_{o}}) \rho $. In this model, the Universe
could be closed but still have a nonrelativistic-matter density corresponding
to its critical value, $\Omega_{o}=1$. Different cosmological expressions, such
as, luminosity distance, angular diameter, number count and ratio of the
redshift tickness-angular size, are determined in terms of the redshift for
this model.

</DOC>
<DOC>
<DOCNO> 150878 </DOCNO>
Field Redefinition Invariance in Quantum Field Theory


  The issue of field redefinition invariance of path integrals in quantum field
theory is reexamined. A ``paradox'' is presented involving the reduction to an
effective quantum-mechanical theory of a $(d+1)$-dimensional free scalar field
in a Minkowskian spacetime with compactified spatial coordinates. The
implementation of field redefinitions both before and after the reduction
suggests that operator-ordering issues in quantum field theory should not be
ignored.

</DOC>
<DOC>
<DOCNO> 102632 </DOCNO>
On the Geometry of Sasakian-Einstein 5-Manifolds


  On simply connected five manifolds Sasakian-Einstein metrics coincide with
Riemannian metrics admitting real Killing spinors which are of great interest
as models of near horizon geometry for three-brane solutions in superstring
theory [KW]. We expand on the recent work of Demailly and Koll\'ar [DK] and
Johnson and Koll\'ar [JK1] who give methods for constructing K\"ahler-Einstein
metrics on log del Pezzo surfaces. By [BG1] circle V-bundles over log del Pezzo
surfaces with K\"ahler-Einstein metrics have Sasakian-Einstein metrics on the
total space of the bundle. Here these simply connected 5-manifolds arise as
links of isolated hypersurface singularities which by the well known work of
Smale [Sm] together with [BG3] must be diffeomorphic to
$\scriptstyle{S^5#l(S^2\times S^3)}.$ More precisely, using methods from Mori
theory in algebraic geometry we prove the existence of 14 inequivalent
Sasakian-Einstein structures on $\scriptstyle{S^2\times S^3}$ and infinite
families of such structures on $\scriptstyle{#l(S^2\times S^3)}$ with
$\scriptstyle{2\leq l\leq7}$. We also discuss the moduli problem for these
Sasakian-Einstein structures.

</DOC>
<DOC>
<DOCNO> 100686 </DOCNO>
Homoclinic tangencies and hyperbolicity for surface diffeomorphisms


  We prove here that in the complement of the closure of the hyperbolic
surface diffeomorphisms, the ones exhibiting a homoclinic tangency are C^1
dense. This represents a step towards the global understanding of dynamics of
surface diffeomorphisms.

</DOC>
<DOC>
<DOCNO> 83358 </DOCNO>
Measuring efficiency in high-accuracy, broad-coverage statistical


  Very little attention has been paid to the comparison of efficiency between
high accuracy statistical parsers. This paper proposes one machine-independent
metric that is general enough to allow comparisons across very different
parsing architectures. This metric, which we call ``events considered'',
measures the number of ``events'', however they are defined for a particular
parser, for which a probability must be calculated, in order to find the parse.
It is applicable to single-pass or multi-stage parsers. We discuss the
advantages of the metric, and demonstrate its usefulness by using it to compare
two parsers which differ in several fundamental ways.

</DOC>
<DOC>
<DOCNO> 10103 </DOCNO>
Structural Properties of Potts Model Partition Functions and Chromatic


  partial abstract: The $q$-state Potts model partition function (equivalent to
the Tutte polynomial) for a lattice strip of fixed width $L_y$ and arbitrary
length $L_x$ has the form
$Z(G,q,v)=\sum_{j=1}^{N_{Z,G,\lambda}}c_{Z,G,j}(\lambda_{Z,G,j})^{L_x}$, where
$v$ is a temperature-dependent variable. The special case of the
zero-temperature antiferromagnet ($v=-1$) is the chromatic polynomial $P(G,q)$.
Using coloring and transfer matrix methods, we give general formulas for
$C_{X,G}=\sum_{j=1}^{N_{X,G,\lambda}}c_{X,G,j}$ for $X=Z,P$ on cyclic and
M\"obius strip graphs of the square and triangular lattice. Combining these
with a general expression for the (unique) coefficient $c_{Z,G,j}$ of degree
$d$ in $q$: $c^{(d)}=U_{2d}(\frac{\sqrt{q}}{2})$, where $U_n(x)$ is the
Chebyshev polynomial of the second kind, we determine the number of
$\lambda_{Z,G,j}$'s with coefficient $c^{(d)}$ in $Z(G,q,v)$ for these cyclic
strips of width $L_y$ to be $n_Z(L_y,d)=(2d+1)(L_y+d+1)^{-1} {2L_y \choose
L_y-d}$ for $0 \le d \le L_y$ and zero otherwise. For both cyclic and M\"obius
strips of these lattices, the total number of distinct eigenvalues
$\lambda_{Z,G,j}$ is calculated to be $N_{Z,L_y,\lambda}={2L_y \choose L_y}$.
We point out that $N_{Z,L_y,\lambda}=2N_{DA,tri,L_y}$ and
$N_{P,L_y,\lambda}=2N_{DA,sq,L_y}$, where $N_{DA,\Lambda,n}$ denotes the number
of directed lattice animals on the lattice $\Lambda$.

</DOC>
<DOC>
<DOCNO> 69864 </DOCNO>
CP violation in B_d \to \phi K_S in SUSY GUT with right-handed neutrinos


  CP violation in the B_d system is discussed in the supersymmetric grand
unified theory (GUT) with the right-handed neutrinos. Above the GUT scale, the
right-handed down-type squarks couple to the right-handed neutrinos. Due to the
renormalization group effect, flavor violations in the lepton sector may be
transfered to the right-handed down-type squark mass matrix, which affects the
CP violation in the B decay. Taking into account this effect, we compare the CP
violation in B_d \to \psi K_S and B_d \to \phi K_S processes. We will find that
a significant difference is possible between the CP violating phases in two
decay processes.

</DOC>
<DOC>
<DOCNO> 117100 </DOCNO>
Nonlinear Effects in CW Mode-Locked Solid-State Lasers with


  The influence of nonlinear properties of semiconductor saturable absorbers on
ultrashort pulse generation was investigated. It was shown, that linewidth
enhancement, quadratic and linear ac Stark effect contribute essentially to the
mode locking in cw solid-state lasers, that can increase the pulse stability,
decrease pulse duration and reduce the mode locking threshold

</DOC>
<DOC>
<DOCNO> 101857 </DOCNO>
Admissible vectors for the regular representation


  It is well known that for irreducible, square-integrable representations of a
locally compact group, there exist so-called admissible vectors which allow the
construction of generalized continuous wavelet transforms.
 In this paper we discuss when the irreducibility requirement can be dropped,
using a connection between generalized wavelet transforms and Plancherel
theory. For unimodular groups with type I regular representation, the existence
of admissible vectors is equivalent to a finite measure condition. The main
result of this paper states that this restriction disappears in the
nonunimodular case: Given a nondiscrete, second countable group $G$ with type I
regular representation $\lambda_G$, we show that $\lambda_G$ itself
 (and hence every subrepresentation thereof) has an admissible vector in the
sense of wavelet theory iff $G$ is nonunimodular.

</DOC>
<DOC>
<DOCNO> 100814 </DOCNO>
Modular invariants from subfactors


  In these lectures we explain the intimate relationship between modular
invariants in conformal field theory and braided subfactors in operator
algebras. A subfactor with a braiding determines a matrix $Z$ which is obtained
as a coupling matrix comparing two kinds of braided sector induction
("alpha-induction"). It has non-negative integer entries, is normalized and
commutes with the S- and T-matrices arising from the braiding. Thus it is a
physical modular invariant in the usual sense of rational conformal field
theory. The algebraic treatment of conformal field theory models, e.g.
$SU(n)_k$ models, produces subfactors which realize their known modular
invariants. Several properties of modular invariants have so far been noticed
empirically and considered mysterious such as their intimate relationship to
graphs, as for example the A-D-E classification for $SU(2)_k$. In the subfactor
context these properties can be rigorously derived in a very general setting.
Moreover the fusion rule isomorphism for maximally extended chiral algebras due
to Moore-Seiberg, Dijkgraaf-Verlinde finds a clear and very general proof and
interpretation through intermediate subfactors, not even referring to
modularity of $S$ and $T$. Finally we give an overview on the current state of
affairs concerning the relations between the classifications of braided
subfactors and two-dimensional conformal field theories. We demonstrate in
particular how to realize twisted (type II) descendant modular invariants of
conformal inclusions from subfactors and illustrate the method by new examples.

</DOC>
<DOC>
<DOCNO> 150582 </DOCNO>
Precise determination of critical exponents and equation of state by


  Renormalization group, and in particular its Quantum Field Theory
implementation has provided us with essential tools for the description of the
phase transitions and critical phenomena beyond mean field theory. We therefore
review the methods, based on renormalized phi^4_3 quantum field theory and
renormalization group, which have led to a precise determination of critical
exponents of the N-vector model (R. Guida and J. Zinn-Justin, J. Phys. A31
(1998) 8103. cond-mat/9803240). and of the equation of state of the 3D Ising
model (R. Guida and J. Zinn-Justin, Nucl. Phys. B489 [FS] (1997) 626,
hep-th/9610223.). These results are among the most precise available probing
field theory in a non-perturbative regime.

</DOC>
<DOC>
<DOCNO> 12846 </DOCNO>
Electron spectral function and algebraic spin liquid for the normal


  We propose to describe the spin fluctuations in the normal state of
underdoped high $T_{c}$ superconductors as a manifestation of an algebraic spin
liquid. We have performed calculations within the slave-boson model to support
our proposal. Under the spin-charge separation picture, the normal state (the
spin-pseudogap phase) is described by massless Dirac fermions, charged bosons,
and a gauge field. We find that the gauge interaction is a marginal
perturbation and drives the mean-field free-spinon fixed point to a more
complicated spin-quantum-fixed-point -- the algebraic spin liquid, where
gapless excitations interact at low energies. The electron spectral function in
the normal state was found to have a Luttinger-liquid-like line shape as
observed in experiments. The spectral function obtained in the superconducting
state shows how a coherent quasiparticle peak appears from the incoherent
background as spin and charge recombine.

</DOC>
<DOC>
<DOCNO> 13722 </DOCNO>
Strong enhancement of superconductivity in a nanosized Pb bridge


  In recent experiments with a superconducting nanosized Pb bridge formed
between a scanning tunneling microscope tip and a substrate, superconductivity
has been detected at magnetic fields, which are few times larger than the third
(surface) critical field. We describe the observed phenomenon on the basis of a
numerical solution of the Ginzburg-Landau equations in a model structure
consisting of six conoids. The spatial distribution of the superconducting
phase is shown to be strongly inhomogeneous, with concentration of the
superconducting phase near the narrowest part (the ``neck'') of the bridge. We
show that suppression of superconductivity in the bridge by applied magnetic
field or by temperature first occurs near the bases and then in the neck
region, what leads to a continuous superconducting-to-normal resistive
transition. A position of the transition midpoint depends on temperature and,
typically, is by one order of magnitude higher than the second critical field
H_c2. We find that the vortex states can be realized in the bridge at low
temperatures T/T_c < 0.6. The vortex states lead to a fine structure of the
superconducting-to-normal resistive transition. We also analyze vortex states
in the bridge, which are characterized by a varying vorticity as a function of
the bridge's height.

</DOC>
<DOC>
<DOCNO> 120013 </DOCNO>
Statistical Perturbation Theory of Cosmic Fields I: Basic Formalism and


  We formulate a general method for perturbative evaluations of statistics of
smoothed cosmic fields, which we call as ``Statistical Perturbation Theory''.
The formalism is an extensive generalization of the method used by Matsubara
(1994) who derived a weakly nonlinear formula of the genus statistic in a 3D
density field. After describing the general method, we apply the formalism
especially to analyses of more general genus statistics, level-crossing
statistics, Minkowski functionals, and a density extrema statistic, regardless
of the dimensions in which each statistic is defined. The relation between the
Minkowski functionals and other geometrical statistics is clearly described.
These examples are applied to some cosmic fields, including 3D density field,
3D velocity field, 2D projected density field, and 2D weak lensing field. The
results are detailed for second order theory of the formalism. The reason why
the genus curves etc. in CDM-like models exhibit smaller deviations from
Gaussian predictions when they are plotted against the volume-fraction
threshold is clarified in the framework of the second order theory. The effect
of the bias is also discussed.

</DOC>
<DOC>
<DOCNO> 12370 </DOCNO>
Competing Quantum Orderings in Cuprate Superconductors: A Minimal Model


  We present a minimal model for cuprate superconductors. At the unrestricted
mean-field level, the model produces homogeneous superconductivity at large
doping, striped superconductivity in the underdoped regime and various
antiferromagnetic phases at low doping and for high temperatures. On the
underdoped side, the superconductor is intrinsically inhomogeneous and global
phase coherence is achieved through Josephson-like coupling of the
superconducting stripes. The model is applied to calculate experimentally
measurable ARPES spectra.

</DOC>
<DOC>
<DOCNO> 102240 </DOCNO>
Dirac Charge Quantization and Generalized Differential Cohomology


  The main new result here is the cancellation of global anomalies in the Type
I superstring, with and without D-branes. Our argument here depends on a
precise interpretation of the 2-form abelian gauge field using KO-theory; then
the anomaly cancellation follows from a geometric form of the full
Atiyah-Singer index theorem for families of Dirac operators. This is a refined
version of the Green-Schwarz mechanism. It seems that a geometric
interpretation of this mechanism-the cancellation of local and global fermion
anomalies against local and global anomalies in the electric coupling of an
abelian gauge field-always proceeds in a similar manner. For example, a
previous paper with M. Hopkins (hep-th/0002027) explains the cancellation of
anomalies in Type II with D-branes in these terms. The focal point of this
paper is a general discussion about abelian gauge fields and Dirac charge
quantization. Namely, we argue that quantization of charge is implemented in
the functional integral by interpreting abelian gauge fields as cochains in a
generalized differential cohomology theory. Our exposition includes elementary
examples as well as examples from superstring theory. The mathematical
underpinnings of differential cohomology are currently under development; we
only give a sketch here. The anomaly cancellation in Type I depends on
properties of a certain quadratic form in KO-theory, which we analyze in an
appendix written jointly with M. Hopkins. In particular, the usual equation
``Tr R^2 = Tr F^2'' is refined to an equation in the KO-theory of spacetime.

</DOC>
<DOC>
<DOCNO> 13357 </DOCNO>
Coupled dynamics of fast spins and slow exchange interactions in the XY


  We investigate an XY spin-glass model in which both spins and interactions
(or couplings) evolve in time, but with widely separated time-scales. For large
times this model can be solved using replica theory, requiring two levels of
replicas, one level for the spins and one for the couplings. We define the
relevant order parameters, and derive a phase diagram in the replica-symmetric
approximation, which exhibits two distinct spin-glass phases. The first phase
is characterized by freezing of the spins only, whereas in the second phase
both spins and couplings are frozen. A detailed stability analysis leads also
to two distinct corresponding de Almeida-Thouless lines, each marking
continuous replica-symmetry breaking. Numerical simulations support our
theoretical study.

</DOC>
<DOC>
<DOCNO> 39995 </DOCNO>
Optics: general-purpose scintillator light response simulation code


  We present the program optics that simulates the light response of an
arbitrarily shaped scintillation particle detector. Predicted light responses
of pure CsI polygonal detectors, plastic scintillator staves, cylindrical
plastic target scintillators and a Plexiglas light-distribution plate are
illustrated. We demonstrate how different bulk and surface optical properties
of a scintillator lead to specific volume and temporal light collection
probability distributions. High-statistics optics simulations are calibrated
against the detector responses measured in a custom-made cosmic muon tomography
apparatus. The presented code can also be used to track particles intersecting
complex geometrical objects.

</DOC>
<DOC>
<DOCNO> 13821 </DOCNO>
Determination of the (3x3)-Sn/Ge(111) structure by photoelectron


  At a coverage of about 1/3 monolayer, Sn deposited on Ge(111) below 550 forms
a metastable (sqrt3 x sqrt3)R30 phase. This phase continuously and reversibly
transforms into a (3x3) one, upon cooling below 200 K. The photoemission
spectra of the Sn 4d electrons from the (3x3)-Sn/Ge(111) surface present two
components which are attributed to inequivalent Sn atoms in T4 bonding sites.
This structure has been explored by photoelectron diffraction experiments
performed at the ALOISA beamline of the Elettra storage ring in Trieste
(Italy). The modulation of the intensities of the two Sn components, caused by
the backscattering of the underneath Ge atoms, has been measured as a function
of the emission angle at fixed kinetic energies and viceversa. The bond angle
between Sn and its nearest neighbour atoms in the first Ge layer (Sn-Ge1) has
been measured by taking polar scans along the main symmetry directions and it
was found almost equivalent for the two components. The corresponding bond
lengths are also quite similar, as obtained by studying the dependence on the
photoelectron kinetic energy, while keeping the photon polarization and the
collection direction parallel to the Sn-Ge1 bond orientation (bond emission). A
clear difference between the two bonding sites is observed when studying the
energy dependence at normal emission, where the sensitivity to the Sn height
above the Ge atom in the second layer is enhanced. This vertical distance is
found to be 0.3 Angstroms larger for one Sn atom out of the three contained in
the lattice unit cell. The (3x3)-Sn/Ge(111) is thus characterized by a
structure where the Sn atom and its three nearest neighbour Ge atoms form a
rather rigid unit that presents a strong vertical distortion with respect to
the underneath atom of the second Ge layer.

</DOC>
<DOC>
<DOCNO> 119220 </DOCNO>
Cosmic Ray Acceleration in Superbubbles and the Composition of Cosmic


  We review the evidence for cosmic ray acceleration in the superbubble/hot
phase of the interstellar medium, and discuss the implications for the
composition of cosmic rays and the structure and evolution of the interstellar
medium. We show that the bulk of the galactic supernovae, their expanding
remnants, together with their metal-rich grain and gas ejecta, and their cosmic
ray accelerating shocks, are all confined within the interiors of superbubbles,
generated by the multiple supernova explosions of massive stars formed in giant
OB associations. This superbubble/hot phase of the ISM provides throughout the
age of the Galaxy a cosmic ray source of essentially constant metallicity for
acceleration by the shocks of many supernovae over time scales of a few Myr,
consistent with both the Be/Fe evolution and ACE observations of Ni-59/Co-59.
We also show that if the refractory cosmic ray metals come from the sputtering
of fast refractory grains then the accompanying scattering of ambient gas by
these fast grains can also account for the relative abundance of cosmic ray
volatiles.

</DOC>
<DOC>
<DOCNO> 152436 </DOCNO>
Comments on Noncommutative Gauge Theories


  We study the gauge theories on noncommutative space. We employ the idea of
the covariant position to understand the linear and angular momenta, the center
of mass position, and to express all gauge invariant observables including the
Wilson line. In addition, we utilize the universality of the U(1) gauge theory,
which originates from the underlying matrix theory, to analyze various solitons
on U(N) theories, like the unstable static vortex solutions in two dimensions
and BPS dyonic fluxon solutions.

</DOC>
<DOC>
<DOCNO> 72089 </DOCNO>
New Scaling at High Energy DIS


  We develop a new approach for solving the non-linear evolution equation in
the low $x_B$ region and show that the remarkable "geometric" scaling of its
solution holds not only in the saturation region, but in much wider kinematical
region. This is in a full agreement with experimental data (Golec-Biernat,
Kwiecinski and Stasto).

</DOC>
<DOC>
<DOCNO> 102720 </DOCNO>
On the Critical Capacity of the Hopfield Model


  We estimate the critical capacity of the zero-temperature Hopfield model by
using a novel and rigorous method. The probability of having a stable fixed
point is one when $\alpha\le 0.113$ for a large number of neurons. This result
is an advance on all rigorous results in the literature and the relationship
between the capacity $\alpha$ and retrieval errors obtained here for small
$\alpha$ coincides with replica calculation results.

</DOC>
<DOC>
<DOCNO> 9817 </DOCNO>
The metallic state in disordered quasi-one-dimensional conductors


  The unusual metallic state in conjugated polymers and single-walled carbon
nanotubes is studied by dielectric spectroscopy (8--600 GHz). We have found an
intriguing correlation between scattering time and plasma frequency. This
relation excludes percolation models of the metallic state. Instead, the
carrier dynamics can be understood in terms of the low density of delocalized
states around the Fermi level, which arises from the competion between
disorder-induced localization and interchain-interactions-induced
delocalization.

</DOC>
<DOC>
<DOCNO> 10183 </DOCNO>
Polyelectrolyte Titration: Theory and Experiment


  Titration of methacrylic acid / ethyl-acrylate copolymers is studied
experimentally and theoretically. At low salt concentrations, this polyacid
exhibits a plateau in the titration curve below the neutralization point. The
plateau has been often attributed to a first-order phase transition associated
with polymer conformational changes. We argue that the specific shape of
titration curves of hydrophobic polyelectrolytes is due to electrostatics and
does not necessarily require a conformation change of the polyelectrolyte
chains. We calculate the free energy at the mean-field level and its
first-order (one loop) correction using a loop expansion. The latter is
dominated by Debye-Huckel--like charge-charge correlations as well as by
correlations between dissociation sites along the polymer chain. We show that
the one-loop corrections to the free energy lead to titration curves that agree
with experiments. In particular, the model explains the decrease of the pH at
the plateau when the polymer concentration is increased or when salt is added
to the solution.

</DOC>
<DOC>
<DOCNO> 84490 </DOCNO>
Einstein-Weyl geometry, the dKP equation and twistor theory


  It is shown that Einstein-Weyl (EW) equations in 2+1 dimensions contain the
dispersionless Kadomtsev-Petviashvili (dKP) equation as a special case: If an
EW structure admits a constant weighted vector then it is locally given by $h=d
y^2-4d xd t-4ud t^2, \nu=-4u_xd t$, where $u=u(x, y, t)$ satisfies the dKP
equation $(u_t-uu_x)_x=u_{yy}$.
  Linearised solutions to the dKP equation are shown to give rise to
four-dimensional anti-self-dual conformal structures with symmetries. All
four-dimensional hyper-K\"ahler metrics in signature $(++--)$ for which the
self-dual part of the derivative of a Killing vector is null arise by this
construction. Two new classes of examples of EW metrics which depend on one
arbitrary function of one variable are given, and characterised.
  A Lax representation of the EW condition is found and used to show that all
EW spaces arise as symmetry reductions of hyper-Hermitian metrics in four
dimensions. The EW equations are reformulated in terms of a simple and closed
two-form on the $\CP^1$-bundle over a Weyl space.
  It is proved that complex solutions to the dKP equations, modulo a certain
coordinate freedom, are in a one-to-one correspondence with minitwistor spaces
(two-dimensional complex manifolds ${\cal Z}$ containing a rational curve with
normal bundle $\O(2)$) that admit a section of $\kappa^{-1/4}$, where $\kappa$
is the canonical bundle of ${\cal Z}$. Real solutions are obtained if the
minitwistor space also admits an anti-holomorphic involution with fixed points
together with a rational curve and section of $\kappa^{-1/4}$ that are
invariant under the involution.

</DOC>
<DOC>
<DOCNO> 170666 </DOCNO>
Schr\"{o}dinger cat state of trapped ions in harmonic and anharmonic


  We examine the time evolution of a two level ion interacting with a light
field in harmonic oscillator trap and in a trap with anharmonicities. The
anharmonicities of the trap are quantified in terms of the deformation
parameter $\tau $ characterizing the q-analog of the harmonic oscillator trap.
Initially the ion is prepared in a Schr\"{o}dinger cat state. The entanglement
of the center of mass motional states and the internal degrees of freedom of
the ion results in characteristic collapse and revival pattern. We calculate
numerically the population inversion I(t), quasi-probabilities $Q(t),$ and
partial mutual quantum entropy S(P), for the system as a function of time.
Interestingly, small deformations of the trap enhance the contrast between
population inversion collapse and revival peaks as compared to the zero
deformation case. For \beta =3 and $4,(% \beta $ determines the average number
of trap quanta linked to center of mass motion) the best collapse and revival
sequence is obtained for \tau =0.0047 and \tau =0.004 respectively. For large
values of \tau decoherence sets in accompanied by loss of amplitude of
population inversion and for \tau \sim 0.1 the collapse and revival phenomenon
disappear. Each collapse or revival of population inversion is characterized by
a peak in S(P) versus t plot. During the transition from collapse to revival
and vice-versa we have minimum mutual entropy value that is S(P)=0. Successive
revival peaks show a lowering of the local maximum point indicating a
dissipative irreversible change in the ionic state. Improved definition of
collapse and revival pattern as the anharminicity of the trapping potential
increases is also reflected in the Quasi- probability versus t plots.

</DOC>
<DOC>
<DOCNO> 178847 </DOCNO>
Rotations in isospace: a doorway to the understanding of neutron-proton


  The $T$=2 excitations in even-even $N$=$Z$ nuclei are calculated within the
isospin cranked mean-field approach. The response of pairing correlations to
rotation in isospace is investigated. It is shown that whereas the isovector
pairing rather modestly modifies the single-particle moment of inertia in
isospace, the isoscalar pairing strongly reduces its value. This reduction of
the moments of inertia in isospace with respect to its rigid body value is a
strong indicator of collective isoscalar pairing correlations. Beautiful
analogies between the role of isovector pairing for the case of spatial
rotations and the role of isoscalar pairing for the case of iso-rotations are
underlined.

</DOC>
<DOC>
<DOCNO> 117227 </DOCNO>
Microwave gyroscope-novel rotation sensor


  High performance microwave gyroscope (MG) is theoretically developed for the
first time to our knowledge. MG is based on Sagnac effect in microwave ring
resonator (RR), where a specially taylored phase shifter (PS) on the basis of
surface acoustic waves is inserted. Due to that beat frequency becomes
proportional to square (or cubic) root upon rotation rate and therefore hugely
increases. In the result MG has few order higher sensitivity and dynamic range
than state-of-the-art laser gyros, so it can serve as an advanced rotation
sensor in navigation and fundamental sciences.

</DOC>
<DOC>
<DOCNO> 10100 </DOCNO>
Reflection of light and heavy holes from a linear potential barrier


  In this paper we study reflection of holes in direct-band semiconductors from
the linear potential barrier. It is shown that light-heavy hole transformation
matrix is universal. It depends only on a dimensionless product of the light
hole longitudinal momentum and the characteristic length determined by the
slope of the potential and doesn't depend on the ratio of light and heavy hole
masses, provided this ratio is small. It is shown that the transformation
coefficient goes to zero both in the limit of small and large longitudinal
momenta, however the phase of a reflected hole is different in these limits. An
approximate analytical expression for the light-heavy hole transformation
coefficient is found.

</DOC>
<DOC>
<DOCNO> 118420 </DOCNO>
Systematic uncertainties in gravitational lensing models: a


  While the Hubble constant can be derived from observable time delays between
images of lensed quasars, the result is often highly sensitive to assumptions
and systematic uncertainties in the lensing model. Unlike most previous authors
we explore a broad class of models with non-parametric lens radial profile and
allow for non-elliptical lens potentials. The axis ratio and position angle of
the lens can be determined from the image positions of quadruple gravitational
lensed systems by solving the lens equation semi-analytically, independent of
the radial profile. We give simple equations for estimating the power-law slope
of the lens density directly from the image positions and for estimating the
time delay ratios. Our method greatly simplifies the numerics for fitting
observations and is fast in exploring the model parameter space. As an
illustration we apply the model to PG1115+080. We show that the measured image
positions and time delays do not uniquely determine the Hubble constant. The
mass-to-light ratio of the lens galaxy increases with radius, higher at image C
than at image B.

</DOC>
<DOC>
<DOCNO> 122481 </DOCNO>
Variable X-ray Absorption in the Seyfert 2 Galaxy Mrk 348


  We present RXTE monitoring observations of the Seyfert 2 galaxy Mrk 348
spanning a 6 month period. The time-averaged spectrum in the 3-20 keV band
shows many features characteristic of a Compton-thin Seyfert 2 galaxy, namely a
hard underlying power-law continuum (photon index = 1.8) with heavy soft X-ray
absorption (N_h ~ 10^23 cm^-2) plus measureable iron line emission (equivalent
width ~ 100 eV) and, at high energy, evidence for a reflection component (R <
1). During the first half of the monitoring period the X-ray continuum flux
from Mrk 348 remained relatively steady. However this was followed by a
significant brightening of the source (by roughly a factor of 4) with the
fastest change corresponding to a doubling of its X-ray flux on a timescale of
about 20 days. The flux increase was accompanied by a marked softening of X-ray
spectrum most likely attributable to a factor 3 decline in the intrinsic
line-of-sight column density. In contrast the iron line and the reflection
components showed no evidence of variability. These observations suggest a
scenario in which the central X-ray source is surrounded by a patchy
distribution of absorbing material located within about a light-week of the
nucleus of Mrk 348. The random movement of individual clouds within the
absorbing screen, across our line of sight, produces substantial temporal
variations in the measured column density on timescales of weeks to months and
gives rise to the observed X-ray spectral variability. However, as viewed from
the nucleus the global coverage and typical thickness of the cloud layer
remains relatively constant.

</DOC>
<DOC>
<DOCNO> 9788 </DOCNO>
Effect of order-parameter fluctuations on the Halperin-Lubensky-Ma


  We show that order-parameter fluctuations in a good type-I superconductor or
a liquid crystal always increase the size of the first-order transition. This
behavior is eventually changed when the system crosses over to inverted-XY
critical behavior, with the size of the first-order transition vanishing as a
power law with a crossover exponent. We find a good agreement between our
theory and a recent experiment on the nematic-smectic-A first-order transition
in 8CB-10CB mixtures of liquid crystals.

</DOC>
<DOC>
<DOCNO> 99607 </DOCNO>
Global Stability for Holomorphic Foliations in Kaehler Manifolds


  We prove the following theorem for Holomorphic Foliations in compact complex
kaehler manifolds: if there is a compact leaf with finite holonomy, then every
leaf is compact with finite holonomy. As corollary we reobtain stability
theorems for compact foliations in Kaehler manifolds of
Edwards-Millett-Sullivan and Hollman.

</DOC>
<DOC>
<DOCNO> 11738 </DOCNO>
Conductance anomalies in quantum wires


  We study the conductance threshold of clean nearly straight quantum wires in
the magnetic field. As a quantitative example we solve exactly the scattering
problem for two-electrons in a wire with planar geometry and a weak bulge. From
the scattering matrix we determine conductance via the Landauer-Buettiker
formalism. The conductance anomalies found near 0.25(2e^2/h) and 0.75(2e^2/h)
are related to a singlet resonance and a triplet resonance, respectively, and
survive to temperatures of a few degrees. With increasing in-plane magnetic
field the conductance exhibits a plateau at e^2/h, consistent with recent
experiments.

</DOC>
<DOC>
<DOCNO> 178595 </DOCNO>
A New Coupling Potential for the Scattering of Deformed Light Heavy-Ions


  This letter introduces a new coupling potential to explain the experimental
data over wide energy ranges for a number of systems. Within the
coupled-channels formalism, this letter first shows the limitations of the
standard coupled-channels theory in the case where one of the nuclei in the
reaction is strongly deformed and then, demonstrates that a global solution to
the problems of light heavy-ion reactions such as $^{12}$C+$^{12}$C,
$^{16}$O+$^{28}$Si and $^{12}$C+$^{24}$Mg can be found using a new
second-derivative coupling potential in the coupled-channels formalism. This
new approach consistently improves the agreement with the experimental data for
the elastic and inelastic scattering data as well as for their excitation
functions using constant or slightly energy-dependent parameters.

</DOC>
<DOC>
<DOCNO> 11950 </DOCNO>
Phase diagram of the extended Hubbard chain with charge-dipole


  We consider a modified extended Hubbard model (EHM) which, in addition to the
on-site repulsion U and nearest-neighbor repulsion V, includes polarization
effects in second-order perturbation theory. The model is equivalent to an EHM
with renormalized U plus a next-nearest-neighbor repulsion term. Using a method
based on topological quantum numbers (charge and spin Berry phases), we
generalize to finite hopping t the quantum phase diagram in one dimension
constructed by van den Brink et al. (Phys. Rev. Lett. 75, 4658 (1995)). At
hopping t=0 there are two charge density-wave phases, one spin density-wave
phase and one intermediate phase with charge and spin ordering, depending on
the parameter values. At t \neq 0 the nature of each phase is confirmed by
studying correlation functions. However, in addition to the strong-coupling
phases, a small region with bond ordering appears. The region occupied by the
intermediate phase first increases and then decreases with increasing t, until
it finally disappears for t of the order but larger than U. For small t, the
topological transitions agree with the results of second order perturbation
theory.

</DOC>
<DOC>
<DOCNO> 9072 </DOCNO>
Magnetic-field-induced singularities in spin dependent tunneling through


  Current steps attributed to resonant tunneling through individual InAs
quantum dots embedded in a GaAs-AlAs-GaAs tunneling device are investigated
experimentally in magnetic fields up to 28 T. The steps evolve into strongly
enhanced current peaks in high fields. This can be understood as a
field-induced Fermi-edge singularity due to the Coulomb interaction between the
tunneling electron on the quantum dot and the partly spin polarized Fermi sea
in the Landau quantized three-dimensional emitter.

</DOC>
<DOC>
<DOCNO> 13889 </DOCNO>
Depinning with dynamic stress overshoots: Mean field theory


  An infinite-range model of an elastic manifold pulled through a random
potential by an applied force $F$ is analyzed focusing on inertial effects.
When the inertial parameter, $M$, is small, there is a continuous depinning
transition from a small-$F$ static phase to a large-$F$ moving phase. When $M$
is increased to $M_c$, a novel tricritical point occurs. For $M\!>\!M_c$, the
depinning transition becomes discontinuous with hysteresis. Yet, the
distribution of discrete ``avalanche''-like events as the force is increased in
the static phase for $M\!>\!M_c$ has an unusual mixture of first-order-like and
critical features.

</DOC>
<DOC>
<DOCNO> 12232 </DOCNO>
Pairing, Charge, and Spin Correlations in the Three-Band Hubbard Model


  Using the Constrained Path Monte Carlo (CPMC) method, we simulated the
two-dimensional, three-band Hubbard model to study pairing, charge, and spin
correlations as a function of electron and hole doping and the Coulomb
repulsion $V_{pd}$ between charges on neighboring Cu and O lattice sites. As a
function of distance, both the $d_{x^2 - y^2}$-wave and extended s-wave pairing
correlations decayed quickly. In the charge-transfer regime, increasing
$V_{pd}$ decreased the long-range part of the correlation functions in both
channels, while in the mixed-valent regime, it increased the long-range part of
the s-wave behavior but decreased that of the d-wave behavior. Still the d-wave
behavior dominated. At a given doping, increasing $V_{pd}$ increased the
spin-spin correlations in the charge-transfer regime but decreased them in the
mixed-valent regime. Also increasing $V_{pd}$ suppressed the charge-charge
correlations between neighboring Cu and O sites. Electron and hole doping away
from half-filling was accompanied by a rapid suppression of anti-ferromagnetic
correlations.

</DOC>
<DOC>
<DOCNO> 100288 </DOCNO>
Bijective proofs for Schur function identities which imply Dodgson's


  We present a ``method'' for bijective proofs for determinant identities,
which is based on translating determinants to Schur functions by the
Jacobi--Trudi identity. We illustrate this ``method'' by generalizing a
bijective construction (which was first used by Goulden) to a class of Schur
function identities, from which we shall obtain bijective proofs for Dodgson's
condensation formula, Pl\"ucker relations and a recent identity of the second
author.

</DOC>
<DOC>
<DOCNO> 40589 </DOCNO>
Pion and Kaon Vector Form Factors


  We develop a unitarity approach to consider the final state interaction
corrections to the tree level graphs calculated from Chiral Perturbation Theory
($\chi PT$) allowing the inclusion of explicit resonance fields. The method is
discussed considering the coupled channel pion and kaon vector form factors.
These form factors are then matched with the one loop $\chi PT$ results. A very
good description of experimental data is accomplished for the vector form
factors and for the $\pi\pi$ P-wave phase shifts up to $\sqrt{s}\lesssim 1.2$
GeV, beyond which multiparticle states play a non negligible role. In
particular the low and resonance energy regions are discussed in detail and for
the former a comparison with one and two loop $\chi PT$ is made showing a
remarkable coincidence with the two loop $\chi PT$ results.

</DOC>
<DOC>
<DOCNO> 7967 </DOCNO>
Phase interference of spin tunneling in an arbitrarily directed magnetic


  We present an exact analytic study on the topological phase interference
effect in resonant quantum tunneling of the magnetization between degenerate
excited levels for biaxial ferromagnets in an arbitrarily directed magnetic
field. We show that the topological phase interference effect depends on the
orientation of the field distinctly. The transition from classical to quantum
behavior is also discussed.

</DOC>
<DOC>
<DOCNO> 7648 </DOCNO>
The Excess Wing in the Dielectric Loss of Glass-Formers: A


  Dielectric loss spectra of glass-forming propylene carbonate and glycerol at
temperatures above and below T_g are presented. By performing aging experiments
lasting up to five weeks, equilibrium spectra below T_g have been obtained.
During aging, the excess wing, showing up as a second power law at high
frequencies, develops into a shoulder. The results strongly suggest that the
excess wing, observed in a variety of glass formers, is the high-frequency
flank of a beta-relaxation.

</DOC>
<DOC>
<DOCNO> 120467 </DOCNO>
Evaporation: The change from accretion via a thin disk to a coronal flow


  We present a model for a corona above a geometrically thin standard disk
around a black hole. This corona is fed by matter from the thin disk which
evaporates from the cool layers underneath. An equilibrium establishes between
the cool accretion stream and the hot flow. In the inner region evaporation
becomes so efficient that at low accretion rates all matter flows via the
corona and proceeds towards the black hole as an advection-dominated accretion
flow (ADAF). We investigate this transition for accretion disks around stellar
black holes. We derive a set of four ordinary differential equations which
describe the relevant processes and solve them numerically. The evaporation
efficiency has a maximum value where the advection-dominated structure of the
corona (at large distances from the black hole) changes to a
radiation-dominated structure (at small distances). This maximum can be related
to the observed spectral transitions in black hole X-ray binaries. Our
solutions of coronal structure are valid for both, accretion in galactic X-ray
transients and in AGN.

</DOC>
<DOC>
<DOCNO> 39632 </DOCNO>
On the possibility of radar echo detection of ultra-high energy cosmic


  We revisit and extend the analysis supporting a 60 year-old suggestion that
cosmic rays air showers resulting from primary particles with energies above
10^{18} eV should be straightforward to detect with radar ranging techniques,
where the radar echoes are produced by scattering from the column of ionized
air produced by the shower. The idea has remained curiously untested since it
was proposed, but if our analysis is correct, such techniques could provide a
significant alternative approach to air shower detection in a standalone array
with high duty cycle, and might provide highly complementary measurements of
air showers detected in existing and planned ground arrays such as the Fly's
Eye or the Auger Project. The method should be particularly sensitive to
showers that are transverse to and relatively distant from the detector, and is
thus effective in characterizing penetrating horizontal showers such as those
that might be induced by ultra-high energy neutrino primaries.

</DOC>
<DOC>
<DOCNO> 118675 </DOCNO>
Resonance Paramagnetic Relaxation and Alignment of Small Grains


  We show that the energy-level splitting arising from grain rotation ensures
that paramagnetic dissipation acts at its maximum rate, i.e., the conditions
for paramagnetic resonance are automatically fulfilled. We refer to this
process as ``resonance relaxation''. The differences between the predictions of
classical Davis-Greenstein relaxation and resonance relaxation are most
pronounced for grains rotating faster than 1 GHz, i.e., in the domain where
classical paramagnetic relaxation is suppressed. This mechanism can partially
align even very small grains, resulting in linearly polarized microwave
emission which could interfere with efforts to measure the polarization of the
cosmic microwave background.

</DOC>
<DOC>
<DOCNO> 7949 </DOCNO>
Unusual T_c variation with hole concentration in


  We have investigated the $T_c$ variation with the hole concentration $p$ in
the La-doped Bi 2201 system, Bi$_2$Sr$_{2-x}$La$_x$CuO$_{6+\delta}$. It is
found that the Bi 2201 system does not follow the systematics in $T_c$ and $p$
observed in other high-$T_c$ cuprate superconductors (HTSC's). The $T_c$ vs $p$
characteristics are quite similar to what observed in Zn-doped HTSC's. An
exceptionally large residual resistivity component in the inplane resistivity
indicates that strong potential scatterers of charge carriers reside in CuO$_2$
planes and are responsible for the unusual $T_c$ variation with $p$, as in the
Zn-doped systems. However, contrary to the Zn-doped HTSC's, the strong scatter
in the Bi 2201 system is possibly a vacancy in the Cu site.

</DOC>
<DOC>
<DOCNO> 13239 </DOCNO>
Macroscopic Manifestation of Microscopic Entropy Production:


  We study a spatial diffusion process generated by velocity fluctuations of
intermittent nature. We note that intermittence reduces the entropy production
rate while enhancing the diffusion strength. We study a case of space-dependent
intermittence and prove it to result in a deviation from uniform distribution.
This macroscopic effect can be used to measure the relative value of the
trajectory entropy.

</DOC>
<DOC>
<DOCNO> 69386 </DOCNO>
A general reduction method for one-loop N-point integrals


  In order to calculate cross sections with a large number of particles/jets in
the final state at next-to-leading order, one has to reduce the occurring
scalar and tensor one-loop integrals to a small set of known integrals. In
massless theories, this reduction procedure is complicated by the presence of
infrared divergences. Working in n=4-2*epsilon dimensions, it will be outlined
how to achieve such a reduction for diagrams with an arbitrary number of
external legs. As a result, any integral with more than four propagators and
generic 4-dimensional external momenta can be reduced to box integrals.

</DOC>
<DOC>
<DOCNO> 83447 </DOCNO>
Execution replay and debugging


  As most parallel and distributed programs are internally non-deterministic --
consecutive runs with the same input might result in a different program flow
-- vanilla cyclic debugging techniques as such are useless. In order to use
cyclic debugging tools, we need a tool that records information about an
execution so that it can be replayed for debugging. Because recording
information interferes with the execution, we must limit the amount of
information and keep the processing of the information fast. This paper
contains a survey of existing execution replay techniques and tools.

</DOC>
<DOC>
<DOCNO> 68745 </DOCNO>
Anatomy of the differential gluon structure function of the proton from


  The use of the differential gluon structure function of the proton ${\cal
F}(x,Q^{2})$ introduced by Fadin, Kuraev and Lipatov in 1975 is called upon in
many applications of small-x QCD. We report here the first determination of
${\cal F}(x,Q^{2})$ from the experimental data on the small-x proton structure
function $F_{2p}(x,Q^{2})$. We give convenient parameterizations for ${\cal
F}(x,Q^{2})$ based partly on the available DGLAP evolution fits (GRV, CTEQ &
MRS) to parton distribution functions and on realistic extrapolations into soft
region. We discuss an impact of soft gluons on various observables. The
x-dependence of the so-determined ${\cal F}(x,Q^{2})$ varies strongly with Q^2
and does not exhibit simple Regge properties. None the less the hard-to-soft
diffusion is found to give rise to a viable approximation of the proton
structure function F_{2p}(x,Q^2) by the soft and hard Regge components with
intercepts \Delta_{soft}=0 and \Delta_{hard}\sim 0.4.

</DOC>
<DOC>
<DOCNO> 118076 </DOCNO>
CMB Anisotropies: A Decadal Survey


  We review the theoretical implications of the past decade of CMB anisotropy
measurements, which culminated in the recent detection of the first feature in
the power spectrum, and discuss the tests available to the next decade of
experiments. The current data already suggest that density perturbations
originated in an inflationary epoch, the universe is spatially flat, and
baryonic dark matter is required. We discuss the underlying assumptions of
these claims and outline the tests required to ensure they are robust. The most
critical test - the presence of a second feature at the predicted location -
should soon be available. Further in the future, secondary anisotropies and
polarization should open new windows to the early and low(er) redshift
universe.

</DOC>
<DOC>
<DOCNO> 123291 </DOCNO>
Starburst Clusters in Galactic Nuclei


  Galactic nuclei often harbor a disproportionately large amount of star
formation activity with respect to their surrounding disks. Not coincidentally,
the density of molecular material in galactic nuclei is often also much greater
than that in disks (Table 1 in Kennicutt 1998). The interplay between rich
populations of young stars and dense molecular environments is evident in our
own Galactic center, which hosts over 10% of Galactic star formation activity
within only $<$0.1% of the volume of the Galactic disk. Data obtained with the
VLA and HST reveal a variety of star forming sites in the Galactic Center,
including a substantial population of stars that are formed in very dense and
massive clusters, while other stars are formed in somewhat sparsely populated
associations of massive stars. Indeed, three of the stellar clusters are the
most massive and densest in the Galaxy. In this paper, we discuss the Galactic
center environment and its compact young star clusters, and compare them to
their counterparts in star forming galactic nuclei, concluding that dense
molecular environments and large velocity dispersions combine to alter star
formation activity in both cases, particularly as regards massive young
clusters.

</DOC>
<DOC>
<DOCNO> 13330 </DOCNO>
Lattice animals on a staircase and Fibonacci numbers


  We study the statistics of column-convex lattice animals resulting from the
stacking of squares on a single or double staircase. We obtain exact
expressions for the number of animals with a given length and area, their mean
length and their mean height. These objects are closely related to Fibonacci
numbers. On a single staircase, the total number of animals with area k is
given by the Fibonacci number F_k.

</DOC>
<DOC>
<DOCNO> 117098 </DOCNO>
Investigation of the Kerr-lens Mode Locking Ability of Cr:ZnSe


  The theoretical calculation for nonlinear refractive index in Cr: ZnSe -
active medium predicts the strong defocusing cascaded second-order nonlinearity
within 2000 - 3000 nm spectral range. On the basis of this result the optimal
cavity configuration for Kerr-lens mode locking is proposed that allows to
achieve a sub-100 fs pulse duration. The numerical simulations testify about
strong destabilizing processes in the laser resulting from a strong self-phase
modulation. The stabilization of the ultrashort pulse generation is possible
due to spectral filtering that increases the pulse duration up to 300 fs.

</DOC>
<DOC>
<DOCNO> 178891 </DOCNO>
Few-Body Problems in Hadron Spectroscopy


  Some rigorous results can be derived using a very simple approach to hadron
spectroscopy, in which a static potential is associated with non-relativistic
kinematics. Several regularities of the experimental spectrum are explained by
such models. It is underlined that certain methods developed for hadronic
physics have found applications in other fields, in particular atomic physics.
A few results can be extended to cases involving spin-dependent forces or
relativistic kinematics.

</DOC>
<DOC>
<DOCNO> 85328 </DOCNO>
Maple procedures in teaching the canonical formalism of general


  We present some Maple procedures using the GrTensorII package for teaching
purposes in the study of the canonical version of the general relativity based
on the ADM formalism

</DOC>
<DOC>
<DOCNO> 122707 </DOCNO>
Interstellar Turbulence: I. Retrieval of Velocity Field Statistics


  We demonstrate the capability of Principal Component Analysis (PCA) as
applied by Heyer & Schloerb (1997) to extract the statistics of turbulent
interstellar velocity fields as measured by the energy spectrum, E(k)= k^-beta.
Turbulent velocity and density fields with known statistics are generated from
fBm simulations. These fields are translated to the observational domain,
T(x,y,v), considering the excitation of molecular rotational energy levels and
radiative transfer. Using PCA and the characterization of velocity and spatial
scales from the eigenvectors and eigenimages respectively, a relationship is
identified which describes the magnitude of line profile differences, deltav,
and the scale, L, over which these differences occur, deltav=L^alpha. From a
series of models with varying values of beta, we find, alpha = 0.33beta - 0.05
for 1 < beta < 3. This provides the basic calibration between the intrinsic
velocity field statistics to observational measures and a diagnostic for
turbulent flows in the interstellar medium. We also investigate the effects of
noise, line opacity, and finite resolution on these results.

</DOC>
<DOC>
<DOCNO> 9268 </DOCNO>
Renormalization Group, hidden symmetries and approximate Ward identities


  Using renormalization group methods, we study the Heisenberg-Ising XYZ chain
in an external magnetic field directed as the z axis, in the case of small
coupling J_3 in the z direction. We study the asymptotic behaviour of the spin
space-time correlation function in the direction of the magnetic field and the
singularities of its Fourier transform.
  The work is organized in two parts. In the present paper an expansion for the
ground state energy and the effective potential is derived, which is convergent
if the running coupling constants are small enough. In the subsequent paper, by
using hidden symmetries of the model, we show that this condition is indeed
verified, if J_3 is small enough, and we derive an expansion for the spin
correlation function. We also prove, by means of an approximate Ward identity,
that a critical index, related with the asymptotic behaviour of the correlation
function, is exactly vanishing.

</DOC>
<DOC>
<DOCNO> 122428 </DOCNO>
Electrodynamic Structure of an Outer-Gap Accelerator: Gamma-Ray Emission


  We investigate a stationary pair production cascade in the outer
magnetosphere of a spinning neutron star. The charge depletion due to a global
current, causes a large electric field along the magnetic field lines.
Migratory electrons and/or positrons are accelerated by this field to radiate
curvature gamma-rays, some of which collide with the X-rays to materialize as
pairs in the gap. The replenished charges partially screen the electric field,
which is self-consistently solved together with the distribution functions of
particles and gamma-rays. If no current is injected at neither of the
boundaries of the accelerator, the gap is located around the so-called null
surface, where the local Goldreich-Julian charge density vanishes. However, we
first find that the gap position shifts outwards (or inwards) when particles
are injected at the inner (or outer) boundary. Applying the theory to the Crab
pulsar, we demonstrate that the pulsed TeV flux does not exceed the
observational upper limit for moderate infrared photon density and that the gap
should be located near to or outside of the null surface so that the observed
spectrum of pulsed GeV fluxes may be emitted via curvature process.

</DOC>
<DOC>
<DOCNO> 117139 </DOCNO>
A Physical Origin for Mass and Charge


  This article proposes a concept called Condensed Electromagnetic Radiation
(CER) as the electromagnetic origin of mass particles. An overwhelming amount
of experimental evidence is consistent with the CER concept as a fundamental
explanation for the physical properties of mass particles. Among many others
cited, two well-established physical phenomena offer especially compelling
evidence: parametric down conversion of photons, and generation of leptons and
quarks.

</DOC>
<DOC>
<DOCNO> 118589 </DOCNO>
The reality of old moving groups - the case of HR 1614


  We prove the existence of the old and metal-rich moving group HR1614. This is
done using the new Hipparcos parallaxes in combination with metallicities
derived from Stromgren photometry, supported by dynamical simulations of the
evolution of old moving groups in the galactic potential. A new selection
criterion for this moving group is presented as well as a new, extended sample
of probable member stars. In particular we find that the HR 1614 moving group
has an age of about 2 Gyr (using Bertelli et al. 1994 isochrones) and a [Fe/H]
= 0.19 +/- 0.06 dex. We also revisit and apply our new selection criterion to
the samples in Eggen (1992) and Eggen (1998). It is found that, when binaries
and stars with too low metallicity have been removed, 15 of his stars fulfill
our criteria.

</DOC>
<DOC>
<DOCNO> 85192 </DOCNO>
Ultracompact stars with multiple necks


  We discuss ultracompact stellar objects which have multiple necks in their
optical geometry. There are in fact physically reasonable equations of state
for which the number of necks can be arbitrarily large. The proofs of these
statements rely on a recent regularized formulation of the field equations for
static spherically symmetric models due to Nilsson and Uggla. We discuss in
particular the equation of state p=\rho-\rho_s which plays a central role in
this context.

</DOC>
<DOC>
<DOCNO> 118194 </DOCNO>
Radio Emission Properties of Millisecond Pulsars


  We report the most recent progress in understanding the emission properties
of millisecond pulsars.

</DOC>
<DOC>
<DOCNO> 122681 </DOCNO>
Large Scale Structure and Cosmic Rays revisited


  We investigate the possibility that ultra high energy cosmic rays (E > 10^19
eV) are related to the distribution of matter on large scales. The large scale
structure (LSS) data stems from the recent IRAS PSCz redshift survey. We
present preliminary predictions drawn from an anisotropic distribution of
sources which follows the galaxy distribution.

</DOC>
<DOC>
<DOCNO> 121838 </DOCNO>
Modeling Observational Signatures of Disk-Driven Outflows


  We present a self-consistent, semi-analytical dynamical model of disk driven
outflows in AGNs that are accelerated by a combination of magnetic stresses and
radiation pressure. This model will make it possible to examine scenarios in
which the wind is homogeneous as well as cases where it consists of dense
clouds embedded in a more tenuous, magnetized medium. The various ingredients
of this model will be tested through quantitative predictions from both
multiwavelength spectral observations and reverberation mapping of AGNs.

</DOC>
<DOC>
<DOCNO> 119952 </DOCNO>
Source depth for solar p-modes


  Theoretically calculated power spectra are compares with observed solar
p-mode velocity power spectra over a range of mode degree and frequency. The
depth for the sources responsible for exciting p-modes of frequency 2.0 mHz is
determined from the asymmetry of their power spectra and found to be about 800
km below the photosphere for quadrupole sources and 150 km if sources are
dipole. The source depth for high frequency oscillations of frequency greater
than about 6 mHz is 180 (50) km for quadrupole (dipole) sources.

</DOC>
<DOC>
<DOCNO> 117150 </DOCNO>
Stability and production of positron-diatomic molecule complexes


  The energies at geometries close to the equilibrium for the e$^+$BeO and
e$^+$LiF ground states were computed by means of diffusion Monte Carlo
simulations. These results allow us to predict the equilibrium geometries and
the vibrational frequencies for these exotic systems,and to discuss their
stability with respect to the various dissociation channels. Since the
adiabatic positron affinities were found to be smaller than the dissociation
energies for both complexes, we propose these two molecules as possible
candidates in the challenge to produce and detect stable positron-molecule
systems.

</DOC>
<DOC>
<DOCNO> 7759 </DOCNO>
Some new exact critical-point amplitudes


  The scaling properties of the free energy and some of universal amplitudes of
a group of models belonging to the universality class of the quantum nonlinear
sigma model and the O(n) quantum $\phi^4$ model in the limit $n\to \infty$ as
well as the quantum spherical model, with nearest-neighbor and long-range
interactions (decreasing at long distances $r$ as $1/r^{d+\sigma}$) is
presented.

</DOC>
<DOC>
<DOCNO> 39815 </DOCNO>
Central Pb+Pb Collisions at 158 A GeV/c Studied by Pion-Pion


  Two-particle correlations have been measured for identified negative pions
from central 158 AGeV Pb+Pb collisions and fitted radii of about 7 fm in all
dimensions have been obtained. A multi-dimensional study of the radii as a
function of kT is presented, including a full correction for the resolution
effects of the apparatus. The cross term Rout-long of the standard fit in the
Longitudinally CoMoving System (LCMS) and the vl parameter of the generalised
Yano-Koonin fit are compatible with 0, suggesting that the source undergoes a
boost invariant expansion. The shapes of the correlation functions in Qinv and
Qspace have been analyzed in detail. They are not Gaussian but better
represented by exponentials. As a consequence, fitting Gaussians to these
correlation functions may produce different radii depending on the acceptance
of the experimental setup used for the measurement.

</DOC>
<DOC>
<DOCNO> 119953 </DOCNO>
Monte Carlo Simulations of Globular Cluster Dynamics


  We have developed a new parallel supercomputer code based on Henon's Monte
Carlo method for simulating the dynamical evolution of globular clusters. This
new code allows us to calculate the evolution of a cluster containing a
realistic number of stars (N ~ 10^5 - 10^6) in about a day of computing time.
The discrete, star-by-star representation of the cluster in the simulation
allows us to treat naturally a number of important processes, including single
and binary star evolution, all dynamical interactions of single stars and
primordial binaries, and tidal interactions with the Galaxy.

</DOC>
<DOC>
<DOCNO> 71509 </DOCNO>
TASI Lectures on The Strong CP Problem


  These lectures discuss the $\theta$ parameter of QCD. After an introduction
to anomalies in four and two dimensions, the parameter is introduced. That such
topological parameters can have physical effects is illustrated with two
dimensional models, and then explained in QCD using instantons and current
algebra. Possible solutions including axions, a massless up quark, and
spontaneous CP violation are discussed.

</DOC>
<DOC>
<DOCNO> 12482 </DOCNO>
Experimental study of a granular gas fluidized by vibrations


  We report experimental results on the behavior of an ensemble of
inelastically colliding particles, excited by a vibrated piston in a vertical
cylinder. When the particle number is increased, we observe a transition from a
regime where the particles have erratic motions (granular "gas") to a
collective behavior where all the particles bounce like a nearly solid body. In
the gaslike regime, we measure the pressure at constant volume, and the bed
expansion at constant external pressure, as a function of the number N of
particles. We also measure the density of particles as a function of the
altitude, and find that the "atmosphere" is exponential far enough from the
piston. From these three independent measurements, we determine a "state
equation" between pressure, volume, particle number and the vibration amplitude
and frequency.

</DOC>
<DOC>
<DOCNO> 100690 </DOCNO>
Nonexistence of smooth Levi-flat hypersurfaces in complex projective


  In this paper we prove the following theorem.
  Main Theorem. Let n >= 3 and m >= 3n/2 +7. Then there exists no C^m
Levi-flat real hypersurface M in P_n.
  The condition that M is Levi-flat means that when M is locally defined by
the vanishing of a C^m real-valued function f, at every point of M the
restriction of d d-bar f to the complex tangent space of M is identically
zero.
  The case of the nonexistence of C^\infty Levi-flat real hypersurface in P_2
is motivated by problems in dynamical systems in P_2.

</DOC>
<DOC>
<DOCNO> 71410 </DOCNO>
Obstructions to dimensional reduction in hot QCD


  I describe results on screening masses in hot gauge theories. Wilsonian
effective long distance theories called dimensionally reduced (DR) theories
describe very well the longest screening length in pure gauge theories. In the
presence of fermions, meson-like screening lengths dominate the long-distance
physics for 3T_c/2 < T < 3 T_c, and thus obstruct perturbative DR.
Extrapolation of our results indicates that a form of this obstruction may
remain till temperatures of 10 T_c or higher, and therefore affect the entire
range of temperature expected to be reached even at the Large Hadron Collider.

</DOC>
<DOC>
<DOCNO> 13979 </DOCNO>
Spectral Decompositions for Evolution Opertors of Mixing Dynamical


  Spectral decompositions for the evolution operator on an energy shell in
phase space are constructed for the free motion on compact 2D surfaces of
constant negative curvature. Applications to quantum chaos and in particular to
the recently proposed ballistic sigma-model are briefly discussed.

</DOC>
<DOC>
<DOCNO> 11673 </DOCNO>
Comment on ``Solution of Classical Stochastic One-Dimensional Many-Body


  In a recent Letter, Bares and Mobilia proposed the method to find solutions
of the stochastic evolution operator $H=H_0 + {\gamma\over L} H_1$ with a
non-trivial quartic term $H_1$. They claim, ``Because of the conservation of
probability, an analog of the Wick theorem applies and all multipoint
correlation functions can be computed.'' Using the Wick theorem, they expressed
the density correlation functions as solutions of a closed set of
integro-differential equations.
  In this Comment, however, we show that applicability of Wick theorem is
restricted to the case $\gamma = 0$ only.

</DOC>
<DOC>
<DOCNO> 39993 </DOCNO>
Status Report on the double-\beta decay experiment NEMO-3


  The NEMO collaboration is presently mounting the NEMO-3 detector in the
Fr\'ejus Underground Laboratory. This detector, which will be completed by the
end of the year 2000, is devoted to the search of neutrinoless double beta
decay with various isotopes. Much attention has been focused on ^{100}Mo and
^{82}Se with their large Q_{\beta\beta}-values. The detector is based on the
direct detection of the two electrons by a tracking device and on the
measurement of their energies by a calorimeter. The aim of the experiment is to
have a sensitivity for the effective neutrino mass on the order of 0.1 eV. The
status and the expected performance of the NEMO-3 detector for both internal
and external background rejections and for signal detection are presented.

</DOC>
<DOC>
<DOCNO> 84461 </DOCNO>
Kaluza-Klein Induced Gravity Inflation


  A D-dimensional induced gravity theory is studied carefully in a $4 + (D-4)$
dimensional Friedmann-Robertson-Walker space-time. We try to extract
information of the symmetry breaking potential in search of an inflationary
solution with non-expanding internal-space. We find that the induced gravity
model imposes strong constraints on the form of symmetry breaking potential in
order to generate an acceptable inflationary universe. These constraints are
analyzed carefully in this paper.

</DOC>
<DOC>
<DOCNO> 8468 </DOCNO>
Fluctuating spin g-tensor in small metal grains


  In the presence of spin-orbit scattering, the splitting of an energy level in
a generic small metal grain due to the Zeeman coupling to a magnetic field B
depends on the direction of B, as a result of mesoscopic fluctuations. The
anisotropy is described by the eigenvalues g_j^2 (j=1,2,3) of a tensor G,
corresponding to the (squares of) g-factors along three principal axes. We
consider the statistical distribution of G and find that the anisotropy is
enhanced by eigenvalue repulsion between the g_j.

</DOC>
<DOC>
<DOCNO> 40408 </DOCNO>
Recent structure function results from neutrino scattering at Fermilab


  We report on the extraction of the structure functions F_2 and Delta xF_3 =
xF_3(nu)-xF_3(nubar) from CCFR nu_mu-Fe and nubar_mu-Fe different ial cross
sections. The extraction is performed in a physics model independent (PMI) way.
This first measurement of Delta xF_3, which is useful in testing models of
heavy charm production, is higher than current theoretical predictios. The
ratio of the F_2 (PMI) values measured in nu_mu and mu scattering is in
agreement (within 5%) with the NLO predictions using massive charm production
schemes, thus resolving the long-standing discrepancy between the two sets of
data. In addition, measurements of F_L (or, equivalently, R) and 2xF_1 are
reported in the kinematic region where anomalous nuclear effects in R are
observed at HERMES.

</DOC>
<DOC>
<DOCNO> 7998 </DOCNO>
Matter Correlations in Branched Polymers


  We analyze correlation functions in a toy model of a random geometry
interacting with matter. We show that in general the connected correlator will
contain a long--range scaling part. This result supports the previously
conjectured general form of correlation functions on random geometries. We
discuss the interplay between matter and geometry and the role of the symmetry
in the matter sector.

</DOC>
<DOC>
<DOCNO> 69655 </DOCNO>
On Geometric Engineering of Supersymmetric Gauge Theories


  We present the basic ideas of geometric engineering of the supersymmetric
quantum field theories viewed as a low energy limit of type II strings and
F-theory on singular Calabi Yau manifolds. We first give the main lines of
toric geometry as it is a powerful technique to deal compact complex manifolds.
Then we introduce mirror symmetry which plays a crucial role in the study of
superstring dualities and finally we give elements on Calabi Yau singularities.
After that we study the geometric engineering of N=2 supersymmetric gauge
theories in six and four dimensions. Finally we make comments regarding $ N=1$
SYM in four dimensions.

</DOC>
<DOC>
<DOCNO> 71839 </DOCNO>
Hyperons, Charm and Beauty Hadrons: Conclusion and Outlook


  In this concluding talk, the advances in the Flavour Problem studies are
discussed, following the structure of the presentations in the Conference. The
subjects touched are organized as follows: Baryons, K-physics, Charm and Beauty
production, Charm and Beauty decays, B-Mixing and CP-Violation, Heavy
Quarkonium.

</DOC>
<DOC>
<DOCNO> 83062 </DOCNO>
A Real World Implementation of Answer Extraction


  In this paper we describe ExtrAns, an answer extraction system. Answer
extraction (AE) aims at retrieving those exact passages of a document that
directly answer a given user question. AE is more ambitious than information
retrieval and information extraction in that the retrieval results are phrases,
not entire documents, and in that the queries may be arbitrarily specific. It
is less ambitious than full-fledged question answering in that the answers are
not generated from a knowledge base but looked up in the text of documents. The
current version of ExtrAns is able to parse unedited Unix "man pages", and
derive the logical form of their sentences. User queries are also translated
into logical forms. A theorem prover then retrieves the relevant phrases, which
are presented through selective highlighting in their context.

</DOC>
<DOC>
<DOCNO> 178790 </DOCNO>
SU(3) symmetry breaking in lower fp-shell nuclei


  Results of shell-model calculations for lower fp-shell nuclei show that SU(3)
symmetry breaking in this region is driven by the single-particle spin-orbit
splitting. However, even though states of the yrast band exhibit SU(3) symmetry
breaking, the results also show that the yrast band B(E2) values are
insensitive to this fragmentation of the SU(3) symmetry; specifically, the
quadrupole collectivity as measured by B(E2) transition strengths between low
lying members of the yrast band remain high even though SU(3) appears to be
broken. Results for $^{44,46,48}Ti$ and $^{48}Cr$ using the Kuo-Brown-3
two-body interaction are given to illustrate these observations.

</DOC>
<DOC>
<DOCNO> 174491 </DOCNO>
A Measurement of Gamow-Teller Strength for 176Yb -> 176Lu and the


  We report a 0-degree 176Yb(p,n)176Lu measurement at IUCF where we used 120
and 160 MeV protons and the energy dependence method to determine GT matrix
elements relative to the Fermi matrix element which can be calculated model
independently. The data show that there is an isolated concentration of GT
strength in the low lying 1+ states making the proposed Low Energy Neutrino
Spectroscopy (LENS) detector (based on neutrino captures on 176Yb) sensitive to
7Be and pp neutrinos and a promising detector to resolve the solar neutrino
problem.

</DOC>
<DOC>
<DOCNO> 8462 </DOCNO>
Nature of the Spin Glass State


  The nature of the spin glass state is investigated by studying changes to the
ground state when a weak perturbation is applied to the bulk of the system. We
consider short range models in three and four dimensions and the infinite range
Sherrington-Kirkpatrick (SK) and Viana-Bray models. Our results for the SK and
Viana-Bray models agree with the replica symmetry breaking picture. The data
for the short range models fit naturally a picture in which there are large
scale excitations which cost a finite energy but whose surface has a fractal
dimension, $d_s$, less than the space dimension $d$. We also discuss a possible
crossover to other behavior at larger length scales than the sizes studied.

</DOC>
<DOC>
<DOCNO> 179052 </DOCNO>
Charge-Exchange Reaction pD->n(pp) in the Bethe-Salpeter Approach


  The deuteron charge - exchange reaction pD->n(pp) for the low values of
momentum transfer and small excitation energies of final pp - pair is
considered in the framework of Bethe - Salpeter approach. The method of
calculation of the observables is developed for the case, when the pp - pair is
in $^1S_0$ - state. The methodical numerical calculations of the differetial
cross sections and tensor analysing powers are presented. The reaction under
consideration is predicted to be a solid base for construction of the deuteron
tensor polarimeter at high energies, and also to obtain some additional
information about elementary nucleon - nucleon charge - exchange amplitude.

</DOC>
<DOC>
<DOCNO> 101504 </DOCNO>
Gel'fand-Dorfman Bialgebras


  This is a survey talk on the study of Gel'fand-Dorfman bialgebras.

</DOC>
<DOC>
<DOCNO> 40052 </DOCNO>
Measurements of the Mass, total Width and Two-Photon Partila Width of


  Using 13.4 $fb^{-1}$ of data collected with the CLEO detector at the Cornell
Electron Storage Ring, we have observed 300 events for the two-photon
production of ground-state pseudo-scalar charmonium in the decay $\eta_c$ ->
$K_S K^{\mp} \pi^{\pm}$. We have measured the $\eta_c$ mass to be (2980.4 +-
2.3 (stat) +- 0.6 (sys)) MeV and its full width as (27.0 +- 5.8 (stat) +- 1.4
(sys)) MeV. We have determined the two-photon partial width of the $\eta_c$
meson to be (7.6 +- 0.8 (stat) +- 0.4 (sys) +- 2.3 (br)) keV, with the last
uncertainty associated with the decay branching fraction.

</DOC>
<DOC>
<DOCNO> 174559 </DOCNO>
Superdeformed Band in ^{36}Ar Described by Projected Shell Model


  The projected shell model implements shell model configuration mixing in the
projected deformed basis. Our analysis on the recently observed superdeformed
band in $^{36}$Ar suggests that the neutron and proton 2-quasiparticle and the
4-quasiparticle bands cross the superdeformed ground band at the same angular
momentum. This constitutes a picture of band disturbance in which the first and
the second band-crossing, commonly seen at separate rotation frequencies in
heavy nuclei, occur simultaneously. We also attempt to understand the
assumptions of two previous theoretical calculations which interpreted this
band. Electromagnetic properties of the band are predicted.

</DOC>
<DOC>
<DOCNO> 84364 </DOCNO>
Locally U(1)*U(1) Symmetric Cosmological Models: Topology and Dynamics


  We show examples which reveal influences of spatial topologies to dynamics,
using a class of spatially {\it closed} inhomogeneous cosmological models. The
models, called the {\it locally U(1)$\times$U(1) symmetric models} (or the {\it
generalized Gowdy models}), are characterized by the existence of two commuting
spatial {\it local} Killing vectors. For systematic investigations we first
present a classification of possible spatial topologies in this class. We
stress the significance of the locally homogeneous limits (i.e., the Bianchi
types or the `geometric structures') of the models. In particular, we show a
method of reduction to the natural reduced manifold, and analyze the
equivalences at the reduced level of the models as dynamical models. Based on
these fundamentals, we examine the influence of spatial topologies on dynamics
by obtaining translation and reflection operators which commute with the
dynamical flow in the phase space.

</DOC>
<DOC>
<DOCNO> 100370 </DOCNO>
On some aspects of the Deligne-Simpson problem


  The Deligne-Simpson problem in the multiplicative version is formulated like
this: {\em give necessary and sufficient conditions for the choice of the
conjugacy classes $C_j\in SL(n,{\bf C})$ so that there exist irreducible
$(p+1)$-tuples of matrices $M_j\in C_j$ satisfying the equality $M_1...
M_{p+1}=I$}. We solve the problem for generic eigenvalues in the case when all
the numbers $\Sigma_{j,m}(\sigma)$ of Jordan blocks of a given matrix $M_j$,
with a given eigenvalue $\sigma$ and of a given size $m$ (taken over all $j$,
$\sigma$, $m$) are divisible by $d>1$. Generic eigenvalues are defined by
explicit algebraic inequalities of the form $a\neq 0$. For such eigenvalues
there exist no reducible $(p+1)$-tuples. The matrices $M_j$ are interpreted as
monodromy operators of regular linear systems on Riemann's sphere.

</DOC>
<DOC>
<DOCNO> 70562 </DOCNO>
Lectures on perturbative HQET 1


  Extended version of lectures given at the University of Karlsruhe and at
Calc-2000 school in Dubna. Properties of HQET as a field theory, methods of
calculation of HQET diagrams and some simple applications are explained in
detail. These lectures can be used as an additional chapter with any modern QCD
textbook.

</DOC>
<DOC>
<DOCNO> 119522 </DOCNO>
Coronal lines and the warm X-ray absorber in Seyfert 1 Galaxies


  The connection between the coronal lines and the warm absorber is examined
systematically. In an earlier work it was found that the coronal line emitting
plasma and the warm absorber gas share the same density and temperature. If
there is a connection between the warm absorber gas and the forbidden
high-ionization line (FHIL) plasma, one can use the profiles of coronal lines
to derive the kinematics and dynamics of the warm absorber due to the high
spectral resolution available in the optical range. Further support for a
connection is a correlation between the equivalent width of [Fe X] 6375 and the
ROSAT spectral index found for an optically selected sample. For X-ray selected
objects with absorption edges observed by ASCA, we looked for a correlation
between the coronal lines and the warm absorber gas. A direct correlation
cannot be confirmed.

</DOC>
<DOC>
<DOCNO> 170816 </DOCNO>
Coherent Control of Quantum Chaotic Diffusion


  Extensive coherent control over quantum chaotic diffusion using the kicked
rotor model is demonstrated and its origin in deviations from random matrix
theory is identified. Further, the extent of control in the presence of
external decoherence is established. The results are relevant to both areas of
quantum chaos and coherent control.

</DOC>
<DOC>
<DOCNO> 12419 </DOCNO>
Clapping modes in unconventional superconductors


  We consider a superconducting state with a mixed symmetry order parameter
components, e.g. $d+is$ or $d+id'$ with $d'= d_{xy}$. We argue for the
existence of the new orbital magnetization mode which corresponds to the
oscillations of relative phase $\phi$ between two components around an
equilibrium value of $\phi = \frac{\pi}{2}$. It is similar to the so called
``clapping'' mode in superfluid $^3He-A$. We estimate the frequency of this
mode $\omega_0(B,T)$ depending on the field and temperature for the specific
case of magnetic field induced $d'$ state. We find that this mode is {\em
tunable} with an applied magnetic field with $\omega_0(B,T) \propto B \0$,
where $\0$ is the magnitude of the d-wave order parameter. We argue also that
similar filed induced clapping mode should be present in an organic p-wave
superconductors.

</DOC>
<DOC>
<DOCNO> 71736 </DOCNO>
Improved approach to the heavy-to-light form factors in the light-cone


  A systematic analysis shows that the main uncertainties in the form factors
are due to the twist-3 wave functions of the light mesons in the light-cone QCD
sum rules. We propose an improved approach, in which the twist-3 wave functions
doesn't make any contribution and therefore the possible pollution by them can
be avoided, to re-examine $B \to \pi$ semileptonic form factors. Also, a
comparison between the previous and our results from the light-cone QCD sum
rules is made. Our method will be beneficial to the precise extracting of
$\mid{V_{ub}}\mid$ from the experimental data on the processes $B \to \pi \ell
\widetilde{\nu_\ell}$.

</DOC>
<DOC>
<DOCNO> 151799 </DOCNO>
Vacuum energies for the relativistic Landau problem


  We study, through zeta-function techniques, the vacuum energies for Dirac
fields in a constant magnetic background. We consider the combined effect of
the background and twisted boundary conditions. The required charge
renormalization is discussed in each case.

</DOC>
<DOC>
<DOCNO> 7801 </DOCNO>
Algebraic Linearization of Dynamics of Calogero Type for any Coxeter


  Calogero-Moser systems can be generalized for any root system (including the
non-crystallographic cases). The algebraic linearization of the generalized
Calogero-Moser systems and of their quadratic (resp. quartic) perturbations are
discussed.

</DOC>
<DOC>
<DOCNO> 71895 </DOCNO>
Quark Masses on the Lattice: Light and Heavy


  I review the current status of lattice calculations of light and heavy quark
masses. Significant progresses, in these studies, have been allowed by the
introduction of improved actions and non-perturbative renormalization
techniques. Current determinations of light quark masses are accurate at the
level of 20%, where the main source of uncertainty is represented by the
quenching error. The determination of the bottom quark mass is accurate at the
impressive level of 2%. As final averages of lattice results, I quote mud(2
GeV) = (4.5 +- 1.0) MeV, ms(2 GeV) = (110 +- 25) MeV and mb(mb) = (4.26 +-
0.09) GeV.

</DOC>
<DOC>
<DOCNO> 151927 </DOCNO>
Singular Phases of Seiberg-Witten Integrable Systems: Weak and Strong


  We consider the singular phases of the smooth finite-gap integrable systems
arising in the context of Seiberg-Witten theory. These degenerate limits
correspond to the weak and strong coupling regimes of SUSY gauge theories. The
spectral curves in such limits acquire simpler forms: in most cases they become
rational, and the corresponding expressions for coupling constants and
superpotentials can be computed explicitly. We verify that in accordance with
the computations from quantum field theory, the weak-coupling limit gives rise
to precisely the "trigonometric" family of Calogero-Moser and open Toda models,
while the strong-coupling limit corresponds to the solitonic degenerations of
the finite-gap solutions. The formulae arising provide some new insights into
the corresponding phenomena in SUSY gauge theories. Some open conjectures have
been proven.

</DOC>
<DOC>
<DOCNO> 10077 </DOCNO>
Calculation of photoemission spectra of the doped Mott insulator


  The spectral properties of La$_{1-x}$Sr$_{x}$TiO$_{3}$, a doped Mott
insulator with strong Coulomb correlations, are calculated with the ab initio
computational scheme LDA+DMFT(QMC). It starts from the non-interacting
electronic band structure as calculated by the local density approximation
(LDA), and introduces the missing correlations by the dynamical mean-field
theory (DMFT), using numerically exact quantum Monte-Carlo (QMC) techniques to
solve the resulting self-consistent multi-band single-impurity problem. The
results of the LDA+DMFT(QMC) approach for the photoemission spectra of
La$_{1-x}$Sr$_{x}$TiO$_{3}$ are in good agreement with experiment and represent
a considerable qualitative and quantitative improvement on standard LDA
calculations.

</DOC>
<DOC>
<DOCNO> 8499 </DOCNO>
Exact Renormalization Group Equations. An Introductory Review


  We critically review the use of the exact renormalization group equations
(ERGE) in the framework of the scalar theory. We lay emphasis on the existence
of different versions of the ERGE and on an approximation method to solve it:
the derivative expansion. The leading order of this expansion appears as an
excellent textbook example to underline the nonperturbative features of the
Wilson renormalization group theory. We limit ourselves to the consideration of
the scalar field (this is why it is an introductory review) but the reader will
find (at the end of the review) a set of references to existing studies on more
complex systems.

</DOC>
<DOC>
<DOCNO> 7670 </DOCNO>
Quantum Theory of the Smectic Metal State in Stripe Phases


  We present a theory of the electron smectic fixed point of the stripe phases
of doped layered Mott insulators. We show that in the presence of a spin gap
three phases generally arise: (a) a smectic superconductor, (b) an insulating
stripe crystal and (c) a smectic metal. The latter phase is a stable
two-dimensional anisotropic non-Fermi liquid. In the abscence of a spin gap
there is also a more conventional Fermi-liquid-like phase. The smectic
superconductor and smectic metal phases may have already been seen in Nd-doped
LSCO.

</DOC>
<DOC>
<DOCNO> 170480 </DOCNO>
On a Physical Metatheory of Consciousness


  We show that the modern quantum mechanics, and particularly the theory of
decoherence, allows for formulating a sort of a physical metatheory of
consciousness. Particularly, the analysis of the necessary conditions for the
occurrence of decoherence, along with the hypothesis that consciousness bears
(more-or-less) well definable physical origin, leads to a wider physical
picture naturally involving consciousness. This can be considered as a sort of
a psycho-physical parallelism, but on rather wide scales bearing some
cosmological relevance.

</DOC>
<DOC>
<DOCNO> 119079 </DOCNO>
ROSAT Observations of the Vela Pulsar


  The ROSAT HRI was used to monitor X-ray emission from the Vela Pulsar. Six
observations span 2-1/2 years and 3 glitches. The summed data yield a
determination of the pulse shape, and X-ray emission from the pulsar is found
to be 12 % pulsed with one broad and two narrow peaks. One observation occurred
15 days after a large glitch. No change in pulse structure was observed and any
change in X-ray luminosity, if present, was less than 3 %. Implications for
neutron star structure are discussed.

</DOC>
<DOC>
<DOCNO> 12653 </DOCNO>
A Statistical Mechanics Approach to the Inherent States of Granular


  We consider a Statistical Mechanics approach to granular systems by following
the original ideas developed by Edwards. We use the concept of ``inherent
states'', defined as the stable configurations in the potential energy
landscape, introduced in the context of glasses. Under simplifying assumptions,
the equilibrium inherent states can be characterised by a configurational
temperature, $1/\beta$. We link $\beta$ to Edwards' compactivity and address
the problem of its experimental measure. We also discuss the possibility to
describe the time dependent distribution probability in the inherent states
with an appropriate master equation.

</DOC>
<DOC>
<DOCNO> 71324 </DOCNO>
DVCS amplitude at tree level: Transversality, twist-3, and factorization


  We study the virtual Compton amplitude in the generalized Bjorken region (q^2
-> Infinity, t small) in QCD by means of a light-cone expansion of the product
of e.m. currents in string operators in coordinate space. Electromagnetic gauge
invariance (transversality) is maintained by including in addition to the
twist-2 operators 'kinematical' twist-3 operators which appear as total
derivatives of twist-2 operators. The non-forward matrix elements of the
elementary twist-2 operators are parametrized in terms of two-variable spectral
functions (double distributions), from which twist-2 and 3 skewed distributions
are obtained through reduction formulas. Our approach is equivalent to a
Wandzura-Wilczek type approximation for the twist-3 skewed distributions. The
resulting Compton amplitude is manifestly transverse up to terms of order
t/q^2. We find that in this approximation the tensor amplitude for longitudinal
polarization of the virtual photon is finite, while the one for transverse
polarization contains a divergence already at tree level. However, this
divergence has zero projection on the polarization vector of the final photon,
so that the physical helicity amplitudes are finite.

</DOC>
<DOC>
<DOCNO> 13642 </DOCNO>
Hydrogen induced nonmonotonic relaxation in binary mixtures similar to


  We have proposed a qualitative model for the structure of binary systems
similar to Pd-Er alloys, which explains their nonmonotonic relaxation after the
hydrogen saturation. It is based on the assumption that such a solid solution
involves two kind heterogeneities. The former are caused by spinodal
decomposition of the initially homogeneous state of the solid solution into the
phases enriched and depleted of Er atoms. The latter are crystalline defects
that trap an additional amount of Er atoms, which leads also to their local
accumulation, changing the defect properties. Hydrogen atoms penetrating into
the solid disturb the equilibrium of both the phase separation and the defect
saturation with Er atoms, causing redistribution of Er atoms. The diffusion
fluxes give rise to the motion of the interface between the two phases that is
responsible for time variations, for example, in the relative volume of the
enriched phase observed experimentally. We have found the conditions when the
interface motion can change the direction during the system relaxation to a new
equilibrium state. The latter effect is, from our point of view, the essence of
the hydrogen induced nonmonotonic relaxation observed in such systems. The
numerical simulation confirms the basic assumptions.

</DOC>
<DOC>
<DOCNO> 174501 </DOCNO>
Heavy Meson Production at COSY - 11


  The COSY-11 collaboration has measured the total cross section for the pp -->
pp eta-prime and pp --> pp eta reactions in the excess energy range from
 Q = 1.5 MeV to Q = 23.6 MeV and from Q = 0.5 MeV to Q = 5.4 MeV, respectively.
 Measurements have been performed with the total luminosity of 73 nb^(-1) for
the pp --> pp eta reaction and 1360 nb^(-1) for the pp --> pp eta-prime one.
Recent results are presented and discussed.

</DOC>
<DOC>
<DOCNO> 71740 </DOCNO>
Weyl symmetric representation of hadronic flux tubes in the dual


  Hadronic flux-tube solutions describing the mesonic and the baryonic states
within the dual Ginzburg-Landau (DGL) theory are investigated by using the dual
lattice formulation in the Weyl-symmetric approach. The shape of the flux tubes
is determined by placement of the color-electric Dirac-string singularity
treated as a connected stack of quantized plaquettes in the dual lattice
formulation. The Weyl symmetric profiles of the hadronic flux tubes are
obtained by using the manifestly Weyl invariant representation of the dual
gauge field.

</DOC>
<DOC>
<DOCNO> 84703 </DOCNO>
Optical geometry for gravitational collapse and Hawking radiation


  The notion of optical geometry, introduced more than twenty years ago as a
formal tool in quantum field theory on a static background, has recently found
several applications to the study of physical processes around compact objects.
In this paper we define optical geometry for spherically symmetric
gravitational collapse, with the purpose of extending the current formalism to
physically interesting spacetimes which are not conformally static. The
treatment is fully general but, as an example, we also discuss the special case
of the Oppenheimer-Snyder model. The analysis of the late time behaviour shows
a close correspondence between the structure of optical spacetime for
gravitational collapse and that of flat spacetime with an accelerating
boundary. Thus, optical geometry provides a natural physical interpretation for
derivations of the Hawking effect based on the ``moving mirror analogy.''
Finally, we briefly discuss the issue of back-reaction in black hole
evaporation and the information paradox from the perspective of optical
geometry.

</DOC>
<DOC>
<DOCNO> 178967 </DOCNO>
Quark model approach to the $\eta$ meson electroproduction on the proton


  A recently developed quark model approach to pseudoscalar meson
photoproduction is extended to electroproduction process for the $\eta$ meson
in the kinematics of momentum transfer $Q^2 \leq$ 4 (GeV/c)$^2$ and total
center of mass energy $W \leq$ 1.6 GeV. Existing data are well reproduced and
the roles of the $S_{11}(1535)$ and $D_{13}(1520)$ resonances are closely
investigated. In the study of the longitudinal excitation of the $S_{11}(1535)$
resonance, a reliable constraint on the $S_{11}(1535)$ properties is obtained
by cleanly removing the electromagnetic transition from the $\gamma_{(v)} p \to
S_{11}(1535) \to \eta p$ amplitude. Thus, the fitted quantities can be
determined with an uncertainty of about 15%. This could be the first direct
constraint on the $S_{11}(1535)$ properties in theory.

</DOC>
<DOC>
<DOCNO> 118494 </DOCNO>
N$_2^+$ and CO$^+$ in Comets 122P/1995 S1 (deVico) and C/1995 O1


  We observed comets 122P/1995\,S1 (deVico) and C/1995\,O1 (Hale-Bopp) with
high spectral resolving power in order to determine the ratio of N$_2^+$/CO$^+$
in their comae. While we clearly detected the CO$^+$ in both of these comets,
no N$_2^+$ was detected in either comet. From these spectra, we derive
sensitive upper limits for N$_2^+$/CO$^+$. These upper limits are substantially
below other reported detections of N$_2^+$/CO$^+$ in other comets. We discuss
the prior N$_2^+$ detections and compare them with our observations. The
abundance of N$_2$ in comets is important to our understanding of the
condensation of ices in the solar nebula. In addition, N$_2$ is a tracer of Ar
so study of N$_2$ allows an understanding of the role of comets for delivering
volatiles to the terrestrial planets. It appears that many, if not most, comets
are depleted in N$_2$ and it will be necessary to search for a mechanism for
depleting this molecule in order to be consistent with current models of the
solar nebula.

</DOC>
<DOC>
<DOCNO> 8355 </DOCNO>
Electron-phonon scattering in quantum wires exposed to a normal magnetic


  A theory for the relaxation rates of a test electron and electron temperature
in quantum wires due to deformation, piezoelectric acoustical and polar optical
phonon scattering is presented. We represent intra- and inter-subband
relaxation rates as an average of rate kernels weighted by electron wave
functions across a wire. We exploit these expressions to calculate phonon
emission power for electron intra- and inter-subband transitions in quantum
wires formed by a parabolic confining potential. In a magnetic field free case
we have calculated the emission power of acoustical (deformation and
piezoelectric interaction) and polar optical phonons as a function of the
electron initial energy for different values of the confining potential
strength. In quantum wires exposed to the quantizing magnetic field normal to
the wire axis, we have calculated the polar optical phonon emission power as a
function of the electron initial energy and of the magnetic field.

</DOC>
<DOC>
<DOCNO> 12684 </DOCNO>
Polarized far-infrared and Raman spectra of SrCuO2 single crystals


  We measured polarized far-infrared reflectivity and Raman scattering spectra
of SrCuO$_2$ single crystals. The frequencies for infrared-active modes were
determined using an oscillator-fitting procedure of reflectivity data. The
Raman spectra were measured at different temperatures using several laser
energies $\omega_L$. In addition to eight of twelve Raman active modes,
predicted by factor-group analysis, we observed a complex structure in the
Raman spectra for polarization parallel to the {\bf c}-axis, which consists of
Raman-allowed A$_g$ symmetry modes, and B$_{1u}$ LO infrared-active
(Raman-forbidden) modes of the first and higher order as well as their
combinations. The Raman-forbidden modes have a stronger intensity at higher
$\omega_L$ than the Raman-allowed ones. In order to explain this resonance
effect, we measured the dielectric function and optical reflection spectra of
SrCuO$_2$ in the visible range. We show that the Raman-allowed A$_g$ symmetry
modes are resonantly enhanced when a laser energy is close to $E_0$, while
Raman-forbidden (IR-active) modes resonate strongly for laser line energies
close to the electronic transition of higher energy gaps.

</DOC>
<DOC>
<DOCNO> 71296 </DOCNO>
Neutrino Oscillation Scenarios and GUT Model Predictions


  The present experimental situation regarding neutrino oscillations is first
summarized, followed by an overview of selected grand unified models which have
been proposed to explain the various scenarios with three active neutrinos and
their right-handed counterparts. Special attention is given to the general
features of the models and their ability to favor some scenarios over others.

</DOC>
<DOC>
<DOCNO> 8404 </DOCNO>
Axial Anomaly in Quasi-1D Chiral Superfluids


  The axial anomaly in a quasi-one-dimensional (quasi-1D) chiral p-wave
superfluid model, which has a epsilon_{x} p_{x}+i epsilon_{y} p_{y}-wave gap in
2D is studied. The anomaly causes an accumulation of the quasiparticle and a
quantized chiral current density in an inhomogeneous magnetic field. These
effects are related to the winding number of the gap. By varying the parameters
epsilon_{x} and epsilon_{y}, the model could be applicable to Sr2RuO4 near the
second superconducting transition point, some quasi-1D organic superconductors
and the fractional quantum Hall state at nu = 5 / 2 Landau level filling
factor.

</DOC>
<DOC>
<DOCNO> 12795 </DOCNO>
Persistent Currents and Dissipation in Narrow Bilayer Quantum Hall Bars


  Bilayer quantum Hall states support a flow of nearly dissipationless
staggered current which can only decay through collective channels. We study
the dominant finite-temperature dissipation mechanism which in narrow bars is
driven by thermal nucleation of pseudospin solitons. We find the
finite-temperature resistivity, predict the resulting staggered current-voltage
characteristics, and calculate the associated zero-temperature critical
staggered current and gate voltage.

</DOC>
<DOC>
<DOCNO> 122019 </DOCNO>
The Red Stellar Contents of Three Selected Fields of The Local Group


  We present a moderately-deep JK photometry for three selected areas of the
dwarf irregular galaxy IC1613. The color-magnitude diagrams contain a mixture
of red supergiants, asymptotic giant branch stars and the brightest red giant
stars. The red supergiants are massive (20 - 25 M_\odot) and young -with ages
between 8 and 25 Myr. The most important result is the evidence of the
decreasing density of the intermediate age AGB population in the vicinity of
the HII regions in the galaxy. We also find age differences between AGB stars
in the main body of the galaxy and those near the HII regions in the
North-East. The former span a range in ages between 1 and 10 Gyr, while the
latter are younger than 1 Gyr. Using the period-luminosity relation derived by
Madore & Freedman (1991) and JK magnitudes of the Cepheid variable V20, we
calculated (m-M)_K = 24.37+-0.2. The recently discovered Nova (King et al.
1999) was identified in Field III. Its presence of our images and its
brightness questioned its classification as a nova.

</DOC>
<DOC>
<DOCNO> 69243 </DOCNO>
Massive Ghosts in Softly Broken SUSY Gauge Theories


  It is shown that, due to soft supersymmetry breaking in gauge theories within
the superfield formalism, there appears the mass for auxiliary gauge fields. It
enters into the RG equations for soft masses of physical scalar particles and
can be eliminated by solving its own RG equation. Explicit solutions up to the
three-loop order in the general case and in the MSSM are given. The
arbitrariness in choosing the initial condition is discussed.

</DOC>
<DOC>
<DOCNO> 119573 </DOCNO>
Annihilating Cold Dark Matter


  Structure formation with cold dark matter (CDM) predicts halos with a central
density cusp, which are observationally disfavored. If CDM particles have an
annihilation cross section sigma*v ~ 10**(-29) (m/GeV) cm**2, then
annihilations will soften the cusps. We discuss plausible scenarios for
avoiding the early Universe annihilation catastrophe that could result from
such a large cross section. The predicted scaling of core density with halo
mass depends upon the velocity dependence of sigma*v, and s-wave annihilation
leads to a core density nearly independent of halo mass, which seems consistent
with observations.

</DOC>
<DOC>
<DOCNO> 178786 </DOCNO>
Quantum Monte Carlo Methods for Nuclei at Finite Temperature


  We discuss finite temperature quantum Monte Carlo methods in the framework of
the interacting nuclear shell model. The methods are based on a representation
of the imaginary-time many-body propagator as a superposition of one-body
propagators describing non-interacting fermions moving in fluctuating auxiliary
fields. Fermionic Monte Carlo calculations have been limited by a ``sign''
problem. A practical solution in the nuclear case enables realistic
calculations in much larger configuration spaces than can be solved by
conventional methods. Good-sign interactions can be constructed for realistic
estimates of certain nuclear properties. We present various applications of the
methods for calculating collective properties and level densities.

</DOC>
<DOC>
<DOCNO> 10034 </DOCNO>
Cluster Analysis of the Ising Model and Universal Finite-Size Scaling


  The recent progress in the study of finite-size scaling (FSS) properties of
the Ising model is briefly reviewed. We calculate the universal FSS functions
for the Binder parameter $g$ and the magnetization distribution function $p(m)$
for the Ising model on $L_1 \times L_2$ two-dimensional lattices with tilted
boundary conditions. We show that the FSS functions are universal for fixed
sets of the aspect ratio $L_1/L_2$ and the tilt parameter. We also study the
percolating properties of the Ising model, giving attention to the effects of
the aspect ratio of finite systems. We elucidate the origin of the complex
structure of $p(m)$ for the system with large aspect ratio by the
multiple-percolating-cluster argument.

</DOC>
<DOC>
<DOCNO> 84959 </DOCNO>
Studies on a New Cosmological Model Based on Complex Metric


  In this thesis, the implications of a new cosmological model are studied,
which has features similar to that of decaying vacuum cosmologies. Decaying
vacuum (or cosmological constant \Lambda) models are the results of attempts to
resolve the problems that plague the standard hot big bang model - the problems
which elude a satisfactory solution even after the two decades of of
inflationary models, the first and much publicised cure to them. We arrive at
the present model by a radically new route, which extends the idea of a
signature change in the metric, a widely discussed speculation in the current
literature. An alternative approach uses some dimensional considerations in
line with quantum cosmology and gives an almost identical model. Both
derivations involve some fundamental issues in general theory of relativity.
The model has a coasting evolution (i.e., a \propto t). It claims the absence
of all the aforementioned puzzles in the standard model and has very good
predictions. In the first two chapters of the thesis, we review the general
theory of relativity, the standard model in cosmology, its successes, the
problems in it and also the most successful of those attempts to solve them,
namely, the inflationary and decaying vacuum models. In the third chapter, we
present and discuss the new cosmological model in detail. The fourth chapter is
concerned with quantum cosmology. We briefly review the canonical quantisation
programme of solving the Wheeler-DeWitt equation, then apply the procedure to
our model and show that it satisfies many of the much sought-after ideals of
this formalism. The last chapter of the thesis compares the new model with
other ones. It also discusses the appearance of a Casimir type negative energy
density in it and the prospects and challenges ahead for the model.

</DOC>
<DOC>
<DOCNO> 9141 </DOCNO>
Effect of Exclusion of Double Occupancies in t-J Model: Extension of


  A new type of analytic estimation of the effect of strong correlation is
developed for the two-dimensional t-J model. It is based on the Gutzwiller
approximation which gives the renormalization of parameters, t and J, due to
the Gutzwiller's projection operator excluding the double occupancies. The
finite-range correlations are taken into account compared with the conventional
Gutzwiller approximation where only the on-site expectation values are
considered. It is shown that the essential point of the renormalization is its
nonlinear dependence on the expectation values of Cooper pairs and
antiferromagnetic moment. In particular the renormalization factor of J becomes
anisotropic in the presence of antiferromagnetic moment, i.e., that for the
z-component is enhanced compared with that for the xy-component. The physical
origin of this enhancement is identified as the surrounding antiferromagnetic
correlations of a bond. The self-consistency equations for the uniform
variational wave functions are derived and solved numerically. Our result gives
a reasonable estimate of antiferromagnetic order parameters near half filling,
in contrast to the conventional slave-boson mean-field theory and the original
Gutzwiller approximation. It is also found that, at half filling, the
renormalization of J represents some of the quantum fluctuations of the
Heisenberg spin system in a different manner from the spin-wave theory. For
finite doping, our results have some similarity to SO(5) symmetric theory.
Applications to the inhomogeneous systems such as the vortex state, around
nonmagnetic impurities, and stripe state are discussed.

</DOC>
<DOC>
<DOCNO> 102574 </DOCNO>
Analytic properties of zeta functions and subgroup growth


  In this paper we introduce some new methods to understand the analytic
behaviour of the zeta function of a group. We can then combine this knowledge
with suitable Tauberian theorems to deduce results about the growth of
subgroups in a nilpotent group. In order to state our results we introduce the
following notation. For \alpha a real number and N a nonnegative integer,
define
  s_N^\alpha(G) = sum_{n=1}^N a_n(G)/n^\alpha.
  Main Theorem: Let G be a finitely generated nilpotent infinite group.
  (1) The abscissa of convergence \alpha(G) of \zeta_G(s) is a rational number
and \zeta_G(s) can be meromorphically continued to Re(s)>\alpha(G)-\delta for
some \delta >0. The continued function is holomorphic on the line \Re(s) =
(\alpha)G except for a pole at s=\alpha(G).
  (2) There exist a nonnegative integer b(G) and some real numbers c,c' such
that
  s_{N}(G) ~ c N^{\alpha(G)}(\log N)^{b(G)}
  s_{N}^{\alpha(G)}(G) ~ c' (\log N)^{b(G)+1}
  for N\rightarrow \infty .

</DOC>
<DOC>
<DOCNO> 68696 </DOCNO>
Gravitational instantons and internal dimensions


  We Study instanton solutions in general relativity with a scalar field. The
metric ansatz we use is composed of a particular warp product of general
Einstein metrics, such as those found in a number of cosmological settings,
including string cosmology, supergravity compactifications and general Kaluza
Klein reductions. Using the Hartle-Hawking prescription the instantons we
obtain determine whether metrics involving extra compact dimensions of this
type are favoured as initial conditions for the universe. Specifically, we find
that these product metric instantons, viewed as constrained instantons, do have
a local minima in the action. These minima are then compared with the higher
dimensional version of the Hawking-Turok instantons, and we argue that the
latter always have lower action than those associated with these product
metrics.

</DOC>
<DOC>
<DOCNO> 121043 </DOCNO>
A Monte Carlo Study of the 6.4 keV Emission at the Galactic Center


  Strong fluorescent Fe line emission at 6.4 keV has been observed from the Sgr
B2 giant molecular cloud located in the Galactic Center region. The large
equivalent width of this line and the lack of an apparent illuminating nearby
object indicate that a time-dependent source, currently in a low-activity
state, is causing the fluorescent emission. It has been suggested that this
illuminator is the massive black hole candidate, Sgr A*, whose X-ray luminosity
has declined by an unprecedented six orders of magnitude over the past 300
years. We here report the results of our Monte Carlo simulations for producing
this line under a variety of source configurations and characteristics. These
indicate that the source may in fact be embedded within Sgr B2, although
external sources give a slightly better fit to the data. The weakened
distinction between the internal and external illuminators is due in part to
the instrument response function, which accounts for an enhanced equivalent
width of the line by folding some of the continuum radiation in with the
intrinsic line intensity. We also point out that although the spectrum may be
largely produced by K$\alpha$ emission in cold gas, there is some evidence in
the data to suggest the presence of warm (~10^5 K) emitting material near the
cold cloud.

</DOC>
<DOC>
<DOCNO> 120732 </DOCNO>
A Structure for Quasars


  This paper proposes a simple, empirically derived, unifying structure for the
inner regions of quasars. This structure is constructed to explain the broad
absorption line (BAL) regions, the narrow `associated' ultraviolet and X-ray
warm absorbers (NALs); and is also found to explain the broad emission line
regions (BELR), and several scattering features, including a substantial
fraction of the broad X-ray Iron-K emission line, and the bi-conical extended
narrow emission line region (ENLR) structures seen on large kiloparsec scales
in Seyfert images. Small extensions of the model to allow luminosity dependent
changes in the structure may explain the UV and X-ray Baldwin effects and the
greater prevalence of obscuration in low luminosity AGN.

</DOC>
<DOC>
<DOCNO> 169658 </DOCNO>
Some conceptual issues involving probability in quantum mechanics


  We discuss some issues about probability in quantum mechanics, with
particular emphasis on the GHZ theorem. We propose the usage of nonmonotonic
upper probabilities as a tool to derive consistent joint upper probabilities
for systems where only contextual hidden variables are possible.

</DOC>
<DOC>
<DOCNO> 178625 </DOCNO>
Reply to the comment on 'Validity of certain soft photon amplitudes'


  We respond to the accompanying Comment on our paper, 'Validity of certain
soft photon amplitudes'. While we hope the discussion here clarifies the
issues, we have found nothing which leads to a change in the original
conclusions of our paper.

</DOC>
<DOC>
<DOCNO> 11679 </DOCNO>
Short wavelength spectrum and Hamiltonian stability of vortex rings


  We compare dynamical and energetical stability criteria for vortex rings. It
is argued that vortex rings will be intrinsically unstable against
perturbations with short wavelengths below a critical wavelength, because the
canonical vortex Hamiltonian is unbounded from below for these modes. To
explicitly demonstrate this behaviour, we derive the oscillation spectrum of
vortex rings in incompressible, inviscid fluids, within a geometrical cutoff
procedure for the core. The spectrum develops an anomalous branch of negative
group velocity, and approaches the zero of energy for wavelengths which are
about six times the core diameter. We show the consequences of this dispersion
relation for the thermodynamics of vortex rings in superfluid $^4$He at low
temperatures.

</DOC>
<DOC>
<DOCNO> 80834 </DOCNO>
Real Representation in Chiral Gauge Theories on the Lattice


  The Weyl fermion belonging to the real representation of the gauge group
provides a simple illustrative example for L\"uscher's gauge-invariant lattice
formulation of chiral gauge theories. We can explicitly construct the fermion
integration measure globally over the gauge-field configuration space in the
arbitrary topological sector; there is no global obstruction corresponding to
the Witten anomaly. It is shown that this Weyl formulation is equivalent to a
lattice formulation based on the Majorana (left--right-symmetric) fermion, in
which the fermion partition function is given by the Pfaffian with a definite
sign, up to physically irrelevant contact terms. This observation suggests a
natural relative normalization of the fermion measure in different topological
sectors for the Weyl fermion belonging to the complex representation.

</DOC>
<DOC>
<DOCNO> 9885 </DOCNO>
Eliminating the mean-field shift in multicomponent Bose-Einstein


  We demonstrate that the nonlinear mean-field shift in a multi-component
Bose-Einstein condensate may be eliminated by controlling the two-body
interaction coefficients. This modification is achieved by, e.g., suitably
engineering the environment of the condensate. We consider as an example the
case of a two-component condensate in a tightly confining atom waveguide.
Modification of the atom-atom interactions is then achieved by varying
independently the transverse wave function of the two components. Eliminating
the density dependent phase shift in a high-density atomic beam has important
applications in atom interferometry and precision measurement.

</DOC>
<DOC>
<DOCNO> 151998 </DOCNO>
M-brane interpolations and (2,0) Renormalization Group flow


  We obtain the M5-M2-MW bound state solutions of 11-dimensional supergravity
corresponding to the 1/2 supersymmetric vacua of the M5-brane equations with
constant background fields. In the `near-horizon' case the solution
interpolates between the $adS_7\times S^4$ Kaluza-Klein vacuum and D=11
Minkowski spacetime via a Domain Wall spacetime. We discuss implications for
renormalization group flow of (2,0) D=6 field theories.

</DOC>
<DOC>
<DOCNO> 150652 </DOCNO>
Scheme Dependence of the Wilsonian Effective Action and Sharp Cutoff


  The cutoff scheme dependence in the several formulations of the Exact
Renormalization Group (ERG) is investigated. It is shown that the cutoff scheme
dependence of the Wilsonian effective action is regarded as a certain
coordinate transformation on the theory space. From this observation the
Wilsonian effective actions are found to suffer from strong dependence on the
schemes even in the infra-red asymptotic region for massive theories. However
there is no such scheme dependence in the one particle irreducible parts of
them, which is called the effective average actions. We also derive the
explicit form of the Polchinski RG equation in the sharp cutoff limit. Finally
this equation is shown to be identical with the Wegner-Houghton RG equation.

</DOC>
<DOC>
<DOCNO> 69155 </DOCNO>
Footprints of a Broad $\sigma$(600) in Weak-Interaction Processes


  We explore how chiral-symmetry constraints on weak-interaction matrix
elements suggest the existence of an intermediate state sigma in several
different weak-interaction processes. Particular attention is directed toward
recent evidence for a sigma within three-body nonleptonic weak decays.

</DOC>
<DOC>
<DOCNO> 69050 </DOCNO>
CP Asymmetries in Radiative B Decays with R-parity Violation


  We analyze the effect of R-parity violation in the minimal supersymmetric
standard model on the CP asymmetries in $b\to s \gamma$ decay. The direct and
mixing-induced CP asymmetries arising from the lepton number violating
couplings are strongly constrained by the current experimental limits on the
corresponding couplings. Allowing a heavy neutrino ($m_{\nu_\tau}\sim10$ keV)
and a moderate mass splitting of sfermions, the direct CP asymmetry around 15 %
and the nearly maximal mixing-induced CP asymmetry ($\sim 100 %$) can be
realized, depending on the R-parity conserving contributions to the radiative
$b$ decay. With the baryon number violating couplings, only the mixing-induced
CP asymmetry arises and it can be maximal provided there is a the similar
sfermion mass splitting.

</DOC>
<DOC>
<DOCNO> 9680 </DOCNO>
Two-Triplet-Dimer Excitation Spectra in the Shastry-Sutherland Model for


  By using the perturbation expansion up to the fifth order, we study the
two-triplet-dimer excitation spectra in the Shastry-Sutherland model, where the
localized nature of a triplet-dimer, the propagation of a triplet-dimer pair by
the correlated hopping and the long-range interactions between triplet-dimers
play an essential role. It is found that the dispersion relations for
first-neighbor triplet-dimer pair excitations with S=1 and p-type symmetry
qualitatively explain the second-lowest branch observed in the neutron
inelastic scattering experiment. It is also predicted that the second-lowest
branch consists of two components, p_x- and p_y-states, with slightly different
excitation energies. The origin of the singlet mode at 3.7meV observed in the
Raman scattering experiment is also discussed.

</DOC>
<DOC>
<DOCNO> 8855 </DOCNO>
Long range correlations in the non-equilibrium quantum relaxation of a


  We consider the non-stationary quantum relaxation of the Ising spin chain in
a transverse field of strength h. Starting from a homogeneously magnetized
initial state the system approaches a stationary state by a process possessing
quasi long range correlations in time and space, independent of the value of
$h$. In particular the system exhibits aging (or lack of time translational
invariance on intermediate time scales) although no indications of coarsening
are present.

</DOC>
<DOC>
<DOCNO> 14062 </DOCNO>
Charged Brown Particle: The More Retardation is - the Lower is the


  The Brownian motion of a charged particle with finite size (described by
Sommerfeld model) is considered. It is found out that due to radiation
reaction: (1) the effective temperature of such particle is lower, and (2) the
acceleration of the average velocity is smaller, than that for classical Brown
particle without electric charge.

</DOC>
<DOC>
<DOCNO> 178651 </DOCNO>
Influence of the Coulomb Interaction on the Chemical Equilibrium of


  The importance of a Coulomb correction to the formalism proposed by Albergo
et al. for determining the temperatures of nuclear systems at break-up and the
ensities of free nucleon gases is discussed. While the proposed correction has
no effect on the temperatures extracted based on double isotope ratios, it
becomes non-negligible when such temperatures or densities of free nucleon
gases are extracted based on multiplicities of heavier fragments of different
atomic numbers.

</DOC>
<DOC>
<DOCNO> 10142 </DOCNO>
Magnetic fluctuations in 2D metals close to the Stoner instability


  We consider the effect of potential disorder on magnetic properties of a
two-dimensional metallic system (with conductance $g\gg 1$) when interaction in
the triplet channel is so strong that the system is close to the threshold of
the Stoner instability. We show, that under these conditions there is an
exponentially small probability for the system to form local spin droplets
which are local regions with non zero spin density. Using a non-local version
of the optimal fluctuation method we find analytically the probability
distribution and the typical spin of a local spin droplet (LSD). In particular,
we show that both the probability to form a LSD and its typical spin are
independent of the size of the droplet (within the exponential accuracy). The
LSDs manifest themselves in temperature dependence of observable quantities. We
show, that below certain cross-over temperature the paramagnetic susceptibility
acquires the Curie-like temperature dependence, while the dephasing time
(extracted from magneto-resistance measurements) saturates.

</DOC>
<DOC>
<DOCNO> 39653 </DOCNO>
Forward Jets, Dijets, and Subjets at the Tevatron


  Recent new results on the determination of the rapidity dependence of the
differential inclusive jet cross section, $<d^{2}\sigma/d\et d\eta >$, as a
function of jet $E_{T}$ in \ppbar collisions at $\sqrt{s}=1800$ GeV, measured
by the D0 detector at the Tevatron, are presented along with the comparisons to
theoretical next-to-leading order (NLO) perturbative QCD predictions. Triple
differential dijet cross sections, $<d^{3}\sigma/d\et d\eta_{1} d\eta_{2}>$, at
$\sqrt{s}=1800$ GeV, as well as the new results on jet structure at
$\sqrt{s}=1800$ and 630 GeV, as measured by the CDF and D0 detectors, are also
discussed.

</DOC>
<DOC>
<DOCNO> 152441 </DOCNO>
One-loop effective potential for scalar and vector fields on higher


  The effective potentials for massless scalar and vector quantum field
theories on D dimensional manifolds with p compact noncommutative extra
dimensions are evaluated by means of dimensional regularization implemented by
zeta function techniques. It is found that the zeta function associated with
the one-loop operator may not be regular at the origin. Thus, the related
heat-kernel trace has a logarithmic term in the short t asymptotics expansion.
Consequences of this fact are briefly discussed.

</DOC>
<DOC>
<DOCNO> 70683 </DOCNO>
Proton decay in SO(10) SUSY GUTs


  We calculate the proton lifetime in an SO(10) supersymmetric grand unified
theory [SUSY GUT] with U(2) family symmetry. This model fits the low energy
data, including the recent data for neutrino oscillations. We discuss the
predictions of this model for the proton lifetime in light of recent
SuperKamiokande results which significantly constrain the SUSY parameter space
of the model.

</DOC>
<DOC>
<DOCNO> 13053 </DOCNO>
Spin correlations in the two-leg antiferromagnetic ladder in a magnetic


  We study the ground-state spin correlations in the gapless incommensurate
regime of a S=1/2 XXZ chain and a two-leg antiferromagnetic ladder under a
magnetic field, in which the gapless excitations form a Tomonaga-Luttinger (TL)
liquid. We calculate numerically the two-spin correlation functions and the
local magnetization in the two models using the density-matrix
renormalization-group method. By fitting the numerical results for an open XXZ
chain of 100 spins to correlation functions of a Gaussian model, we determine
the TL-liquid parameter K and the amplitudes of the correlation functions. The
value of K estimated from the fits is in excellent agreement with the exact
value obtained from the Bethe ansatz. We apply the same method to the open
ladder consisting of 200 spins and determine the dependence of K on the
magnetization M. The K-M relation changes drastically depending on the ratio of
the coupling constants in the leg and rung directions. We also discuss
implications of these results to experiments on the nuclear spin relaxation
rate 1/T_1 and dynamical spin structure factors.

</DOC>
<DOC>
<DOCNO> 70748 </DOCNO>
Analytical QCD and multiparticle production


  We review the perturbative approach to multiparticle production in hard
collision processes. It is investigated to what extent parton level analytical
calculations at low momentum cut-off can reproduce experimental data on the
hadronic final state. Systematic results are available for various observables
with the next-to-leading logarithmic accuracy (the so-called modified leading
logarithmic approximation - MLLA). We introduce the analytical formalism and
then discuss recent applications concerning multiplicities, inclusive spectra,
correlations and angular flows in multi-jet events. In various cases the
perturbative picture is surprisingly successful, even for very soft particle
production.

</DOC>
<DOC>
<DOCNO> 69199 </DOCNO>
The decays $\bar{B}\to \bar{K}D$ and $\bar{B}\to \bar{K}\bar{D}$ and


  The decays $\bar{B}\to \bar{K}D$ and $\bar{B}\to \bar{K}\bar{D}$ taking into
account final state interactions are discussed. These decays are described by
four strong phases $\delta_0, \delta_1, \tilde{\delta}_0, \tilde{\delta}_1$
(subscript 0 and 1 refer to I=0 and I=1 isospin final states), one weak phase
$\gamma $ and four real amplitudes. Isospin constraints are taken into account.
It is argued that strong interaction dynamics gives $\delta_1\approx
\tilde{\delta}_1$. The four real amplitudes are estimated. Some observable
consequences are discussed.

</DOC>
<DOC>
<DOCNO> 119174 </DOCNO>
Population and Size Distribution of Small Jovian Trojan Asteroids


  We present a study of Jovian Trojan objects detected serendipitously during
the course of a sky survey conducted at the University of Hawaii 2.2-meter
telescope. We used a 8192 x 8192 pixel charge-coupled device (CCD) mosaic to
observe 20 deg^2 at locations spread over the L4 Lagrangian swarm and reached a
limiting magnitude V = 22.5 mag (50% of maximum detection efficiency).
Ninety-three Jovian Trojans were detected with radii 2 - 20 km (assumed albedo
0.04). Their differential magnitude distribution has a slope of 0.40 +/- 0.05
corresponding to a power law size distribution index 3.0 +/- 0.3 (1-sigma). The
total number of L4 Trojans with radii > 1 km is of order 1.6 x 10^5 and their
combined mass (dominated by the largest objects) is ~ 10^{-4} M_{Earth}. The
bias-corrected mean inclination is 13.7 +/- 0.5 deg. We also discuss the size
and spatial distribution of the L4 swarm.

</DOC>
<DOC>
<DOCNO> 39919 </DOCNO>
Electromagnetic production of vector mesons at low energies


  We have investigated exclusive photoproduction of light vector mesons
($\omega$, $\rho$ and $\phi$) on the nucleon at low energies. In order to
explore the questions concerning the so-called missing nucleon resonances, we
first establish the predictions from a model based on the Pomeron and meson
exchange mechanisms. We have also explored the contributions due to the
mechanisms involving $s$- and $u$-channel intermediate nucleon state. Some
discrepancies found at the energies near threshold and large scattering angles
suggest a possibility of using this reaction to identify the nucleon
resonances.

</DOC>
<DOC>
<DOCNO> 121111 </DOCNO>
Stars and Planetary Nebulae in the Galactic Bulge


  We compare the populations of Red Giant stars and Planetary Nebulae in the
Galactic Bulge, in the light of recent determinations of their abundances
patterns. We find both populations to be compatible. From the planetary
nebulae, we find evidences that the Bulge did not form stars recently. The
whole abundances pattern remains however puzzling, some elements favoring a
quick evolution of the Galactic Bulge (Mg and Ti), and others a much slower one
(He, O, Si, S, Ar and Ca).

</DOC>
<DOC>
<DOCNO> 174465 </DOCNO>
Baryon Rapidity Loss in Relativistic Au+Au Collisions


  An excitation function of proton rapidity distributions for different
centralities is reported from AGS Experiment E917 for Au+Au collisions at 6, 8,
and 10.8 GeV/nucleon. The rapidity distributions from peripheral collisions
have a valley at midrapidity which smoothly change to distributions that peak
at midrapidity for central collisions. The mean rapidity loss increases with
increasing beam energy, whereas the fraction of protons consistent with
isotropic emission from a thermal source at midrapidity decreases with
increasing beam energy.

</DOC>
<DOC>
<DOCNO> 101383 </DOCNO>
Rigorous semiclassical results for the magnetic response of an electron


  Consider a free electron gas in a confining potential and a magnetic field in
arbitrary dimensions. If this gas is in thermal equilibrium with a reservoir at
temperature $T >0$, one can study its orbital magnetic response (omitting the
spin). One defines a conveniently ``smeared out'' magnetization $M$, and the
corresponding magnetic susceptibility $\chi$, which will be analyzed from a
semiclassical point of view, namely when $\hbar$ (the Planck constant) is small
compared to classical actions characterizing the system. Then various regimes
of temperature $T$ are studied where $M$ and $\chi$ can be obtained in the form
of suitable asymptotic $\hbar$-expansions. In particular when $T$ is of the
order of $\hbar$, oscillations ``\`a la de Haas-van Alphen'' appear, that can
be linked to the classical periodic orbits of the electronic motion.

</DOC>
<DOC>
<DOCNO> 72283 </DOCNO>
Space-Time Foam Effects on Particle Interactions and the GZK Cutoff


  Modelling space-time foam using a non-critical Liouville-string model for the
quantum fluctuations of D branes with recoil, we discuss the issues of momentum
and energy conservation in particle propagation and interactions. We argue that
momentum should be conserved exactly during propagation and on the average
during interactions, but that energy is conserved only on the average during
propagation and is in general not conserved during particle interactions,
because of changes in the background metric. We discuss the possible
modification of the GZK cutoff on high-energy cosmic rays, in the light of this
energy non-conservation as well as the possible modification of the usual
relativistic momentum-energy relation.

</DOC>
<DOC>
<DOCNO> 13180 </DOCNO>
Combined potential and spin impurity scattering in cuprates


  We present a theory of combined nonmagnetic and magnetic impurity scattering
in anisotropic superconductors accounting for the momentum-dependent impurity
potential. Applying the model to the d-wave superconducting state, we obtain a
quantitative agreement with the initial suppression of the critical temperature
due to Zn and Ni substitutions as well as electron irradiation defects in the
cuprates. We suggest, that the unequal pair-breaking effect of Zn and Ni may be
related to a different nature of the magnetic moments induced by these
impurities.

</DOC>
<DOC>
<DOCNO> 85628 </DOCNO>
Conformal Cosmology and Supernova Data


  We define the cosmological parameters $H_{c,0}$, $\Omega_{m,c}$ and
$\Omega_{\Lambda, c}$ within the Conformal Cosmology as obtained by the
homogeneous approximation to the conformal-invariant generalization of
Einstein's General Relativity theory. We present the definitions of the age of
the universe and of the luminosity distance in the context of this approach. A
possible explanation of the recent data from distant supernovae Ia without a
cosmological constant is presented.

</DOC>
<DOC>
<DOCNO> 170099 </DOCNO>
A possible experimental test to decide if quantum mechanical randomness


  A simple experiment using radioactive decay is proposed to test the
possibility of a determinsistic, but chaotic, origin of quantum mechanical
randomness.

</DOC>
<DOC>
<DOCNO> 117956 </DOCNO>
A New Dark Matter Model for Galaxies


  In this paper a new theory of Dark Matter is proposed. Experimental analysis
of several Galaxies show how the non-gravitational contribution to galactic
Velocity Rotation Curves can be interpreted as that due to the Cosmological
Constant $\Lambda$. The experimentally determined values for $\Lambda$ are
found to be consistent with those expected from Cosmological Constraints. The
Cosmological Constant is interpreted as leading to a constant energy density
which in turn can be used to partly address the energy deficit problem (Dark
Energy) of the Universe. The work presented here leads to the conclusion that
the Cosmological Constant is negative and that the universe is de-accelerating.
This is in clear contradiction to the Type Ia Supernovae results which support
an accelerating universe.

</DOC>
<DOC>
<DOCNO> 151580 </DOCNO>
Black Hole Entropy, Special Geometry and Strings


  We review work done over the last years on the macroscopic and microscopic
entropy of supersymmetric black holes in fourdimensional N=2 supergravity and
in N=2 compactifications of string theory and M-theory. Particular emphasis is
put on the crucial role of higher curvature terms and of modifications of the
area law in obtaining agreement between the macroscopic entropy, which is a
geometric property of black hole solutions and the microscopic entropy, which
is computed by state counting in Calabi-Yau compactifications of string or
M-theory. We also discuss invariance properties of the entropy under stringy
T-duality and S-duality transformations in N=2,4 compactifications in presence
of higher curvature terms.
  In order to make the paper self-contained we review the laws of black hole
mechanics in higher derivative gravity, the definition of entropy as a surface
charge, the superconformal off-shell description of N=2 supergravity, special
geometry, and N=2 compactifications of heterotic and type II string theory and
of M-theory.

</DOC>
<DOC>
<DOCNO> 118596 </DOCNO>
How Stochastic is the Relative Bias Between Galaxy Types?


  Examining the nature of the relative clustering of different galaxy types can
help tell us how galaxies formed. To measure this relative clustering, I
perform a joint counts-in-cells analysis of galaxies of different spectral
types in the Las Campanas Redshift Survey (LCRS). I develop a
maximum-likelihood technique to fit for the relationship between the density
fields of early- and late-type galaxies. This technique can directly measure
nonlinearity and stochasticity in the biasing relation. At high significance, a
small amount of stochasticity is measured, corresponding to a correlation
coefficient of about 0.87 on scales corresponding to 15 Mpc/h spheres. A large
proportion of this signal appears to derive from errors in the selection
function, and a more realistic estimate finds a correlation coefficient of
about 0.95. These selection function errors probably account for the large
stochasticity measured by Tegmark & Bromley (1999), and may have affected
measurements of very large-scale structure in the LCRS. Analysis of the data
and of mock catalogs shows that the peculiar geometry, variable flux limits,
and central surface-brightness selection effects of the LCRS do not seem to
cause the effect.

</DOC>
<DOC>
<DOCNO> 116490 </DOCNO>
An Extended Transformation to Reach Continuous Gauge Invariance for


  The paper provides an extended local gauge transformation. By means of it,
the Lagrangian of gauge fields with masses can keep unchanged in the continuous
transformations. In this way, the Higgs mechanism becomes unnecessary and we do
not need to suppose the existence of the Higgs particles.

</DOC>
<DOC>
<DOCNO> 122089 </DOCNO>
Shape and geometry of galaxy clusters and the SZ effect


  We discuss the influence of the finite extension and the geometry of clusters
of galaxies, as well as of the polytropic temperature profile, on the
determination of the Hubble constant.

</DOC>
<DOC>
<DOCNO> 169840 </DOCNO>
Nonlinear Decoherence in Quantum State Preparation of a Trapped Ion


  We present a nonlinear decoherence model which models decoherence effect
caused by various decohereing sources in a quantum system through a nonlinear
coupling between the system and its environment, and apply it to investigating
decoherence in nonclassical motional states of a single trapped ion. We obtain
an exactly analytic solution of the model and find very good agreement with
experimental results for the population decay rate of a single trapped ion
observed in the NIST experiments by Meekhof and coworkers (D. M. Meekhof, {\it
et al.}, Phys. Rev. Lett. {\bf 76}, 1796 (1996)).

</DOC>
<DOC>
<DOCNO> 85531 </DOCNO>
HBO and Periastron Precession around the X-ray Neutron Star


  Based on the periastron precession model to account for kHz QPO of the binary
X-ray neutron star, proposed by Stella and Vietri, we ascribe the 15-60 Hz
Quasi Periodic Oscillation (QPO) to the periastron precession frequency of the
orbiting accreted matter at the boundary of magnetosphere-disk of X-ray neutron
star (NS). The obtained conclusions include: all QPO frequencies increase with
increasing the accretion rate. The theoretical relations between 15-60 Hz QPO
(HBO) frequency and the twin kHz QPOs are similar to the measured empirical
formula. Further, the better fitted NS mass by the proposed model is about 1.9
solar masses for the detected LMXBs.

</DOC>
<DOC>
<DOCNO> 170134 </DOCNO>
Universality of Decoherence


  We consider environment induced decoherence of quantum superpositions to
mixtures in the limit in which that process is much faster than any competing
one generated by the Hamiltonian $H_{\rm sys}$ of the isolated system. While
the golden rule then does not apply we can discard $H_{\rm sys}$. By allowing
for simultaneous couplings to different reservoirs, we reveal decoherence as a
universal short-time phenomenon independent of the character of the system as
well as the bath and of the basis the superimposed states are taken from. We
discuss consequences for the classical behavior of the macroworld and quantum
measurement: For the decoherence of superpositions of macroscopically distinct
states the system Hamiltonian is always negligible.

</DOC>
<DOC>
<DOCNO> 13780 </DOCNO>
Effects of surfaces on resistor percolation


  We study the effects of surfaces on resistor percolation at the instance of a
semi-infinite geometry. Particularly we are interested in the average
resistance between two connected ports located on the surface. Based on general
grounds as symmetries and relevance we introduce a field theoretic Hamiltonian
for semi-infinite random resistor networks. We show that the surface
contributes to the average resistance only in terms of corrections to scaling.
These corrections are governed by surface resistance exponents. We carry out
renormalization group improved perturbation calculations for the special and
the ordinary transition. We calculate the surface resistance exponents
$\phi_{\mathcal S \mathnormal}$ and $\phi_{\mathcal S \mathnormal}^\infty$ for
the special and the ordinary transition, respectively, to one-loop order.

</DOC>
<DOC>
<DOCNO> 8715 </DOCNO>
Energy landscapes in random systems, driven interfaces and wetting


  We discuss the zero-temperature susceptibility of elastic manifolds with
quenched randomness. It diverges with system size due to low-lying local
minima. The distribution of energy gaps is deduced to be constant in the limit
of vanishing gaps by comparing numerics with a probabilistic argument. The
typical manifold response arises from a level-crossing phenomenon and implies
that wetting in random systems begins with a discrete transition. The
associated ``jump field'' scales as $<h > \sim L^{-5/3}$ and $L^{-2.2}$ for
(1+1) and (2+1) dimensional manifolds with random bond disorder.

</DOC>
<DOC>
<DOCNO> 68485 </DOCNO>
Relativistic Corrections for Plarized J/\Psi-Production in b-quark decay


  We analyse the structure of relativistic corrections in the inclusive
production of polarized $J/\Psi$ from b-quark decay. The analysis is performed
not only for the production channel in which the $c\bar c$ pair is a color
sinlet, but also for the channels in which the $c\bar c$ is a color octet. We
find that the correction in the color-singlet channel at the tree-level is
completely determined by the decay constant of $J/\Psi$, while in the
color-octet channels the corrections are characterized by three matrix elements
defined in NRQCD, whose numerical values are unknown. We discuss the impact of
these corrections on the polarized $J/\Psi$% -production, and the impact is so
significant that the predictions based on the analysis for the considered
process may be unreliable. Finally, we propose an integrated spin observable to
measure the polarization of $J/\Psi$%

</DOC>
<DOC>
<DOCNO> 100386 </DOCNO>
Kick stability in groups and dynamical systems


  We consider a general construction of ``kicked systems''. Let G be a group of
measure preserving transformations of a probability space. Given its
one-parameter/cyclic subgroup (the flow), and any sequence of elements (the
kicks) we define the kicked dynamics on the space by alternately flowing with
given period, then applying a kick. Our main finding is the following stability
phenomenon: the kicked system often inherits recurrence properties of the
original flow. We present three main examples. 1) G is the torus. We show that
for generic linear flows, and any sequence of kicks, the trajectories of the
kicked system are uniformly distributed for almost all periods. 2) G is a
discrete subgroup of PSL(2,R) acting on the unit tangent bundle of a Riemann
surface. The flow is generated by a single element of G, and we take any
bounded sequence of elements of G as our kicks. We prove that the kicked system
is mixing for all sufficiently large periods if and only if the generator is of
infinite order and is not conjugate to its inverse in G. 3) G is the group of
Hamiltonian diffeomorphisms of a closed symplectic manifold. We assume that the
flow is rapidly growing in the sense of Hofer's norm, and the kicks are
bounded. We prove that for a positive proportion of the periods the kicked
system inherits a kind of energy conservation law and is thus superrecurrent.
We use tools of geometric group theory and symplectic topology.

</DOC>
<DOC>
<DOCNO> 169924 </DOCNO>
Vibrational Superposition States Without Rotating Wave Approximation


  We propose a scheme to generate superpositions of coherent states for the
vibrational motion of a laser cooled trapped-ion. It is based on the
interaction with a standing wave making use of the counter-rotating terms, i.e.
not applying the rotating wave approximation. We also show that the same scheme
can be exploited for quantum state measurement, i.e. with the same scheme
non-classical states may be reconstructed

</DOC>
<DOC>
<DOCNO> 102031 </DOCNO>
Multidimensional (n+1)-Webs with Reduct Reducible Subwebs


  We find three characterizations for a multidimensional (n+1)-web W possessing
a reduct reducible subweb: its closed form equations, the integrability of an
invariant distribution associated with W, and the relations between the
components of its torsion tensor. In the case of codimension one, the latter
criterion establishes a relation with solutions of a system of nonlinear
second-order PDEs. Some particular cases of this system were considered by
Goursat in 1899.

</DOC>
<DOC>
<DOCNO> 40158 </DOCNO>
Rare Kaon Decay Experiments


  The status of rare kaon decay experiments is reviewed. With the current
generation of experiments now finishing, several exciting new results are
available. New limits in the search for Lepton Flavor Violation (LFV) will be
discussed, as will new limits and measurements of the CKM matrix parameters.
The next generation of rare kaon decay experiments and their contribution to
determination of CKM parameters will also be discussed.

</DOC>
<DOC>
<DOCNO> 9608 </DOCNO>
Valence bond ground states in quantum antiferromagnets and quadratic


  The wave functions corresponding to the zero energy eigenvalue of a
one-dimensional quantum chain Hamiltonian can be written in a simple way using
quadratic algebras. Hamiltonians describing stochastic processes have
stationary states given by such wave functions and various quadratic algebras
were found and applied to several diffusions processes. We show that similar
methods can also be applied for equilibrium processes. As an example, for a
class of q-deformed O(N) symmetric antiferromagnetic quantum chains, we give
the zero energy wave functions for periodic boundary conditions corresponding
to momenta zero and $\pi$. We also consider free and various non-diagonal
boundary conditions and give the corresponding wave functions. All correlation
lengths are derived.

</DOC>
<DOC>
<DOCNO> 8472 </DOCNO>
Extremal-point Densities of Interface Fluctuations


  We introduce and investigate the stochastic dynamics of the density of local
extrema (minima and maxima) of non-equilibrium surface fluctuations. We give a
number of exact, analytic results for interface fluctuations described by
linear Langevin equations, and for on-lattice, solid-on-solid surface growth
models. We show that in spite of the non-universal character of the quantities
studied, their behavior against the variation of the microscopic length scales
can present generic features, characteristic to the macroscopic observables of
the system. The quantities investigated here present us with tools that give an
entirely un-orthodox approach to the dynamics of surface morphologies: a
statistical analysis from the short wavelength end of the Fourier decomposition
spectrum. In addition to surface growth applications, our results can be used
to solve the asymptotic scalability problem of massively parallel algorithms
for discrete event simulations, which are extensively used in Monte-Carlo type
simulations on parallel architectures.

</DOC>
<DOC>
<DOCNO> 8168 </DOCNO>
Effective Actions and Phase Fluctuations in d-wave Superconductors


  We study effective actions for order parameter fluctuations at low
temperature in layered d-wave superconductors such as the cuprates. The order
parameter lives on the bonds of a square lattice and has two amplitude and two
phase modes associated with it. The low frequency spectral weights for
amplitude and relative phase fluctuations is determined and found to be
subdominant to quasiparticle contributions. The Goldstone phase mode and its
coupling to density fluctuations in charged systems is treated in a
gauge-invariant manner. The Gaussian phase action is used to study both the
$c$-axis Josephson plasmon and the more conventional in-plane plasmon in the
cuprates. We go beyond the Gaussian theory by deriving a coarse-grained quantum
XY model, which incorporates important cutoff effects overlooked in previous
studies. A variational analysis of this effective model shows that in the
cuprates, quantum effects of phase fluctuations are important in reducing the
zero temperature superfluid stiffness, but thermal effects are small for $T <<
T_c$.

</DOC>
<DOC>
<DOCNO> 12601 </DOCNO>
Josephson effects in a superconductor-normal metal mesoscopic structure


  We studied a mesoscopic cross-like normal metal structure connected to two
superconducting (S) and two normal (N) reservoirs. We observed the Josephson
effect under unusual conditions when there is no current through one of the two
S/N interfaces. The potential difference between the S reservoirs was zero
unless the voltage applied between S and N reservoirs exceeded a critical value
although the electric potential in the N wire connecting the superconductors
varied in a nonmonotonic way. The observed effects are discussed theoretically.

</DOC>
<DOC>
<DOCNO> 70552 </DOCNO>
Next-to-leading order QCD corrections to parity-violating 3-jet


  In this work we provide all the missing ingredients for calculating
parity-violating 3-jet observables in e^+e^- collisions at next-to-leading
order (NLO) including the full quark mass dependence. In particular we give
explicit results for the one-loop corrections and for the singular
contributions from real emission processes. Our formulae allow for the
computation of the NLO 3-jet contributions to the forward-backward asymmetry
for heavy flavours, which is -- and will be -- an important observable for
electroweak physics at present and future e^+e^- colliders.

</DOC>
<DOC>
<DOCNO> 13058 </DOCNO>
Exchange Effects in the Invar Hardening: $Fe_{0.65}Ni_{0.35}$ as a test


  An increase of the critical resolved shear stress of Invar alloys (Invar
hardening) with a lowering temperature is explained. The effect is caused by a
growth of the exchange interaction between dangling $d$-electron states of
dislocation cores and paramagnetic obstacles (e.g., Ni atoms in FeNi alloys)
which occurs below the Curie temperature. The spins of the two electrons align
along the magnetization due to the exchange interaction with the surrounding
atoms of the ferromagnetic. The exchange interaction between the dislocations
and obstacles is enhanced in Invars due to a strong growth of the magnetic
moments of atoms under the action of elastic strains near the dislocation
cores. Parameters characterizing the exchange interaction are determined for
the case of the Fe$_{0.65}$Ni$_{0.35}$ Invar. The influence of the internal
magnetic field on the dislocation detachment from the obstacles is taken into
account. The obtained temperature dependence of the critical resolved shear
stress in the Fe$_{0.65}$Ni$_{0.35}$ Invar agrees well with the available
experimental data. Experiments facilitating a further check of the theoretical
model are suggested.

</DOC>
<DOC>
<DOCNO> 151939 </DOCNO>
Localization of Various Bulk Fields on a Brane


  We report the issues of localization of various bulk fields on a brane in a
curved background from a local field-theoretic viewpoint where a special
attention is paid to a warp geometry in a general space-time dimension. We
point out that spin 0 scalar field and spin 2 graviton are naturally localized
on a brane with the exponentially decreasing warp factor, while spin 1/2 and
3/2 fermionic fields can be localized on the brane by introducing a bulk mass
term with a 'kink' profile. {}For the localization of spin 1 vector field on
the brane with the exponentially decreasing warp factor, it is shown that there
are essentially two ways. One way is to appeal to the Dvali-Shifman method
which is based on a peculiar feature of the non-abelian gauge dynamics such as
bulk confinement, whereas the other way is to look for a solution of Einstein
equations in such a way that the geometry has a property of confining the
vector field to the brane by a gravitational interaction as in six dimensions.
We point out that the latter way is more universal.

</DOC>
<DOC>
<DOCNO> 11572 </DOCNO>
Quantum Dot and Hole Formation in Sputter Erosion


  Recently it was experimentally demonstrated that sputtering under normal
incidence leads to the formation of spatially ordered uniform nanoscale islands
or holes. Here we show that these nanostructures have inherently nonlinear
origin, first appearing when the nonlinear terms start to dominate the surface
dynamics. Depending on the sign of the nonlinear terms, determined by the shape
of the collision cascade, the surface can develop regular islands or holes with
identical dynamical features, and while the size of these nanostructures is
independent of flux and temperature, it can be modified by tuning the ion
energy.

</DOC>
<DOC>
<DOCNO> 67728 </DOCNO>
Soft Modes, Quantum Transport and Kinetic Entropy


  The effects of the propagation of particles which have a finite life-time and
an according width in their mass spectrum are discussed in the context of
transport descriptions. In the first part the coupling of soft photon modes to
a source of charged particles is studied in a classical model which can be
solved completely in analytical terms. The solution corresponds to a
re-summation of certain field theory diagrams. The general properties of broad
resonances in dense finite temperature systems are discussed at the example of
the $\rho$-meson in hadronic matter. The second part addresses the problem of
transport descriptions which also account for the damping width of the
particles. The Kadanoff--Baym equation after gradient approximation together
with the $\Phi$-derivable method of Baym provides a self-consistent and
conserving scheme. Memory effects appearing in collision term diagrams of
higher order are discussed. We derive a generalized expression for the
nonequilibrium kinetic entropy flow, which includes corrections from
fluctuations and mass-width effects. In special cases an $H$-theorem is proved.
Memory effects in collision terms provide contributions to the kinetic entropy
flow that in the Fermi-liquid case recover the famous bosonic type $T^3 \ln T$
correction to the specific heat of liquid Helium-3.

</DOC>
<DOC>
<DOCNO> 121464 </DOCNO>
HST/NICMOS2 coronagraphic observations of the circumstellar environment


  The close environment of four old Pre-Main Sequence stars has been observed
thanks to the coronagraphic mode of the HST/NICMOS2 camera at lambda=1.6
micron. In the course of this program, the detection of a circumstellar annulus
around HD 141569 has already been presented in Augereau et al.(1999b). In this
paper, we report the detection of an elliptical structure around the Herbig Be
star HD 100546 extending from the very close edge of the coronagraphic mask
(~50 AU) to 350-380 AU (3.5-3.8 arcsec) from the star. The axis ratio gives a
disk inclination of 51+/-3 degrees to the line-of-sight and a position angle of
161+/-5 degrees, measured east of north. At 50 AU, the disk has a surface
brightness between 10.5 and 11 mag/arcsec^2, then follows a -2.92+/-0.04 radial
power law up to 250-270 AU and finally falls as r^{-5.5+/-0.2}. The inferred
optical thickness suggests that the disk is at least marginally optically thick
inside 80 AU and optically thin further out. Combined with anisotropic
scattering properties, this could explain the shape of a brightness asymmetry
observed along the minor axis of the disk. This asymmetry needs to be
confirmed. The circumstellar disks around SAO 206462 and MWC 480 are not
resolved, leading to constraints on the dust distribution. A tight binary
system separated by only 0.32+/-0.04 arcsec is nevertheless detected in the
close vicinity of SAO 206462.

</DOC>
<DOC>
<DOCNO> 8532 </DOCNO>
Thermodynamic properties of extremely diluted symmetric Q-Ising neural


  Using the replica-symmetric mean-field theory approach the thermodynamic and
retrieval properties of extremely diluted {\it symmetric} $Q$-Ising neural
networks are studied. In particular, capacity-gain parameter and
capacity-temperature phase diagrams are derived for $Q=3, 4$ and $Q=\infty$.
The zero-temperature results are compared with those obtained from a study of
the dynamics of the model. Furthermore, the de Almeida-Thouless line is
determined. Where appropriate, the difference with other $Q$-Ising
architectures is outlined.

</DOC>
<DOC>
<DOCNO> 151858 </DOCNO>
Schwinger terms in two-dimensional gravitation and Kallen's method


  We evaluate the gravitational Schwinger terms for the specific
two-dimensional model of Weyl fermions in a gravitational background field
using a technique introduced by Kallen and find a relation which connects the
Schwinger terms with the linearized gravitational anomalies.

</DOC>
<DOC>
<DOCNO> 70416 </DOCNO>
The GZK Bound and Strong Neutrino-Nucleon Interactions above 10^19eV: a


  Cosmic ray events above 10^19 eV have posed a fundamental problem for more
than thirty years. Recent measurements indicate that these events do not show
the features predicted by the GZK bound. The events may, in addition, display
angular correlations with point sources. If these observations are confirmed
for point sources further than 50 - 100 Mpc, then strong interactions for the
neutrino are indicated. Recent work on extra spatial dimensions provides a
context for massive spin-2 exchanges capable of generating cross sections in
the 1 - 100 mb range, as indicated by data. Applications of extra-dimension
physics are controversial, and we comment on several contentious issues.

</DOC>
<DOC>
<DOCNO> 119802 </DOCNO>
Surveys for z > 3 Damped Lyman-alpha Absorption Systems


  We have completed spectroscopic observations using LRIS on the Keck 1
telescope of 30 very high redshift quasars, 11 selected for the presence of
damped Ly-alpha absorption systems and 19 with redshifts z > 3.5 not previously
surveyed for absorption systems. We have surveyed an additional 10 QSOs with
the Lick 120'' and the Anglo-Australian Telescope. We have combined these with
previous data resulting in a statistical sample of 646 QSOs and 85 damped
Ly-alpha absorbers with column densities N(HI) >= 2 x 10^20 atoms/cm^2 covering
the redshift range 0.008 <= z <= 4.694. To make the data in our statistical
sample more readily available for comparison with scenarios from various
cosmological models, we provide tables that includes all 646 QSOs from our new
survey and previously published surveys. They list the minimum and maximum
redshift defining the redshift path along each line of sight, the QSO emission
redshift, and when an absorber is detected, the absorption redshift and
measured HI column density. [see the paper for the complete abstract]

</DOC>
<DOC>
<DOCNO> 14072 </DOCNO>
Dynamics in a supercooled molecular liquid: Theory and Simulations


  We report extensive simulations of liquid supercooled states for a simple
three-sites molecular model, introduced by Lewis and Wahnstr"om [L. J. Lewis
and G. Wahnstr"om, Phys. Rev. E 50, 3865 (1994)] to mimic the behavior of
ortho-terphenyl. The large system size and the long simulation length allow to
calculate very precisely --- in a large q-vector range --- self and collective
correlation functions, providing a clean and simple reference model for
theoretical descriptions of molecular liquids in supercooled states. The time
and wavevector dependence of the site-site correlation functions are compared
with detailed predictions based on ideal mode-coupling theory, neglecting the
molecular constraints. Except for the wavevector region where the dynamics is
controlled by the center of mass (around 9 nm-1), the theoretical predictions
compare very well with the simulation data. ~

</DOC>
<DOC>
<DOCNO> 8460 </DOCNO>
Long-time-tail Effects on Lyapunov Exponents of a Random,


  We study the Lyapunov exponents for a moving, charged particle in a
two-dimensional Lorentz gas with randomly placed, non-overlapping hard disk
scatterers placed in a thermostatted electric field, $\vec{E}$. The low density
values of the Lyapunov exponents have been calculated with the use of an
extended Lorentz-Boltzmann equation. In this paper we develop a method to
extend these results to higher density, using the BBGKY hierarchy equations and
extending them to include the additional variables needed for calculation of
Lyapunov exponents. We then consider the effects of correlated collision
sequences, due to the so-called ring events, on the Lyapunov exponents. For
small values of the applied electric field, the ring terms lead to
non-analytic, field dependent, contributions to both the positive and negative
Lyapunov exponents which are of the form ${\tilde{\epsilon}}^{2}
\ln\tilde{\epsilon}$, where $\tilde{\epsilon}$ is a dimensionless parameter
proportional to the strength of the applied field. We show that these
non-analytic terms can be understood as resulting from the change in the
collision frequency from its equilibrium value, due to the presence of the
thermostatted field, and that the collision frequency also contains such
non-analytic terms.

</DOC>
<DOC>
<DOCNO> 101959 </DOCNO>
Periodic vortex lattices for the Lawrence-Doniach model of layered


  We consider the Lawrence-Doniach model for layered superconductors, in which
stacks of parallel superconducting planes are coupled via the Josephson effect.
We assume that the superconductor is placed in an external magnetic field
oriented parallel to the superconducting planes and study periodic lattice
configurations in the limit as the Josephson coupling parameter r tends to
zero. This limit leads to the "transparent state" discussed in the physics
literature, which is observed in very anisotropic high-temperature
superconductors at sufficiently high applied fields and below a critical
temperature. We use a Lyapunov-Schmidt reduction to prove that energy
minimization uniquely determines the geometry of the optimal vortex lattice: a
period-2 (in the layers) array proposed by Bulaevskii & Clem. Finally, we
discuss the apparent conflict with previous results for finite-width samples,
in which the minimizer in the small coupling regime takes the form of "vortex
planes" (introduced by Theodorakis and Kuplevakhsky.)

</DOC>
<DOC>
<DOCNO> 13805 </DOCNO>
Critical Phenomena and Renormalization-Group Theory


  We review results concerning the critical behavior of spin systems at
equilibrium. We consider the Ising and the general O($N$)-symmetric
universality class. For each of them, we review the estimates of the critical
exponents, of the equation of state, of several amplitude ratios, and of the
two-point function of the order parameter. We report results in three and two
dimensions. We discuss the crossover phenomena that are observed in this class
of systems. In particular, we review the field-theoretical and numerical
studies of systems with medium-range interactions. Moreover, we consider
several examples of magnetic and structural phase transitions, which are
described by more complex Landau-Ginzburg-Wilson Hamiltonians, such as
$N$-component systems with cubic anisotropy, O($N$)-symmetric systems in the
presence of quenched disorder, frustrated spin systems with noncollinear or
canted order, and finally, a class of systems described by the tetragonal
Landau-Ginzburg-Wilson Hamiltonian with three quartic couplings. The results
for the tetragonal Hamiltonian are original, in particular we present the
six-loop perturbative series for the $\beta$-functions and the critical
exponents.

</DOC>
<DOC>
<DOCNO> 121919 </DOCNO>
An XMM-Newton detection of the z=5.80 X-ray weak quasar SDSSp


  We report on an XMM-Newton observation of the most distant known quasar,
SDSSp J104433.04-012502.2, at z=5.80. We have detected this quasar with high
significance in the rest-frame 3.4-13.6 keV band, making it the most distant
cosmic object detected in X-rays; 32 +/- 9 counts were collected. SDSSp
J104433.04-012502.2 is notably X-ray weak relative to other luminous, optically
selected quasars, with alpha_ox=-1.91 +/- 0.05 and a 3.4-13.6 keV luminosity of
about 1.8 x 10^{44} erg/s. The most likely reason for its X-ray weakness is
heavy absorption with N_H greater than about 10^{24} 1/cm^2, as is seen in some
Broad Absorption Line quasars and related objects; we discuss this and other
possibilities. High-quality spectroscopy from 0.95-1.10 microns to search for
blueshifted C IV absorption may elucidate the origin of the X-ray weakness.

</DOC>
<DOC>
<DOCNO> 9633 </DOCNO>
Simple stochastic models showing strong anomalous diffusion


  We show that {\it strong} anomalous diffusion, i.e. $\mean{|x(t)|^q} \sim
t^{q \nu(q)}$ where $q \nu(q)$ is a nonlinear function of $q$, is a generic
phenomenon within a class of generalized continuous-time random walks. For such
class of systems it is possible to compute analytically nu(2n) where n is an
integer number. The presence of strong anomalous diffusion implies that the
data collapse of the probability density function P(x,t)=t^{-nu}F(x/t^nu)
cannot hold, a part (sometimes) in the limit of very small x/t^\nu, now
nu=lim_{q to 0} nu(q). Moreover the comparison with previous numerical results
shows that the shape of F(x/t^nu) is not universal, i.e., one can have systems
with the same nu but different F.

</DOC>
<DOC>
<DOCNO> 102805 </DOCNO>
On ultraproducts of Boolean Algebras and irr


  We prove the consistency of irr(prod limits_{i<kappa}B_i/D)< prod
limits_{i<kappa}irr(B_i)/D, where D is an ultrafilter on kappa and each B_i is
a Boolean Algebra. This solves the last problem of this form from the Monk's
list of problems, that is number 35. The solution applies to many other
properties, e.g., Souslinity. Next, we get similar results with kappa = aleph_1
(easily we cannot have it for kappa=aleph_0) and Boolean Algebras B_i (i<
kappa) of cardinality < beth_{omega_1}.

</DOC>
<DOC>
<DOCNO> 10220 </DOCNO>
Direct Evidence for the Localized Single-Triplet Excitations and the


  We performed inelastic neutron scattering on the 2D Shastry-Sutherland system
SrCu2(11BO3)2 with an exact dimer ground state. Three energy levels at around
3, 5 and 9 meV were observed at 1.7 K. The lowest excitation at 3.0 meV is
almost dispersionless with a bandwidth of 0.2 meV at most, showing a
significant constraint on a single-triplet hopping owing to the orthogonality
of the neighboring dimers. In contrast, the correlated two-triplets excitations
at 5 meV exhibit a more dispersive behavior.

</DOC>
<DOC>
<DOCNO> 67941 </DOCNO>
Loop-after-loop contribution to the second-order Lamb shift in


  We present a numerical evaluation of the loop-after-loop contribution to the
second-order self-energy for the ground state of hydrogenlike atoms with low
nuclear charge numbers Z. The calculation is carried out in the Fried-Yennie
gauge and without an expansion in Z \alpha. Our calculation confirms the
results of Mallampalli and Sapirstein and disagrees with the calculation by
Goidenko and coworkers. A discrepancy between different calculations is
investigated. An accurate fitting of the numerical results provides a detailed
comparison with analytic calculations based on an expansion in the parameter Z
\alpha. We confirm the analytic results of order \alpha^2 (Z\alpha)^5 but
disagree with Karshenboim's calculation of the \alpha^2 (Z \alpha)^6 \ln^3(Z
\alpha)^{-2} contribution.

</DOC>
<DOC>
<DOCNO> 85214 </DOCNO>
Effects of Pair Creation on Charged Gravitational Collapse


  We investigate the effects of pair creation on the internal geometry of a
black hole, which forms during the gravitational collapse of a charged massless
scalar field. Classically, strong central Schwarzschild-like singularity forms,
and a null, weak, mass-inflation singularity arises along the Cauchy horizon,
in such a collapse. We consider here the discharge, due to pair creation, below
the event horizon and its influence on the {\it dynamical formation} of the
Cauchy horizon. Within the framework of a simple model we are able to trace
numerically the collapse. We find that a part of the Cauchy horizon is replaced
by the strong space-like central singularity. This fraction depends on the
value of the critical electric field, $E_{\rm cr}$, for the pair creation.

</DOC>
<DOC>
<DOCNO> 120200 </DOCNO>
Magnetic collimation of the solar and stellar winds


  We resolve the paradox that although magnetic collimation of an isotropic
solar wind results in an enhancement of its proton flux along the polar
directions, several observations indicate a wind proton flux peaked at the
equator. To that goal, we solve the full set of the time-dependent MHD
equations describing the axisymmetric outflow of plasma from the magnetized and
rotating Sun, either in its present form of the solar wind, or, in its earlier
form of a protosolar wind. Special attention is directed towards the
collimation properties of the solar outflow at large heliocentric distances.
For the present day solar wind it is found that the poloidal streamlines and
fieldlines are only slightly focused toward the solar poles. However, even such
a modest compression of the flow by the azimuthal magnetic field would lead to
an increase of the mass flux at the polar axis by about 20% at 1 AU, relatively
to its value at the equator, for an initially isotropic at the base wind,
contrary to older and recent (Prognoz, Ulysses, SOHO) observations. For the
anisotropic in heliolatitude wind with parameters at the base inferred from in
situ observations by ULYSSES/SWOOPS and SOHO/CDS the effect of collimation is
almost totally compensated by the initial velocity and density anisotropy of
the wind. This effect should be taken into account in the interpretation of the
recent SOHO observations by the SWAN instrument. Similar simulations have been
performed for a five- and ten-fold increase of the solar angular velocity
corresponding presumably to the wind of an earlier phase of our Sun. For such
conditions it is found that for initially radial streamlines, the azimuthal
magnetic field created by the fast rotation focus them toward the rotation axis
and forms a tightly collimated jet.

</DOC>
<DOC>
<DOCNO> 122672 </DOCNO>
Two Boehm-Vitense gaps in the main sequence of the Hyades


  Hipparcos proper motions and trigonometric parallaxes allow the derivation of
secular parallaxes which fix the distances to individual stars in the Hyades
cluster to an accuracy of \sim 2 percent. The resulting color-absolute
magnitude diagram for 92 high-fidelity single members of the cluster displays a
very narrow main sequence, with two turn-offs and associated gaps. These occur
at the locations where the onset of surface convection affects the B-V colors,
as predicted by Boehm-Vitense thirty years ago. The new distances provide
stringent constraints on the transformations of colors and absolute magnitudes
to effective temperatures and luminosities, and on models of stellar interiors.

</DOC>
<DOC>
<DOCNO> 80800 </DOCNO>
Vortex dominance of the 0+ and 2+ glueball mass in SU(2) lattice gauge


  The c-vortex ensembles are constructed by means of the recently proposed
cooling method which gradually removes the SU(2)/Z_2 coset fields from the
SU(2) lattice configurations and which thus reveals the Z_2 vortex vacuum
texture. Using Teper's blocking method, the screening masses of the 0+ and the
2+ glueball is calculated from these vortex ensembles and compared with the
masses obtained from full configurations. The masses of either case agree
within the achieved numerical accuracy of 10%. As a byproduct, we find that the
overlaps of the Teper operators with the glueball wavefunctions are
significantly larger in the case of the c-vortex ensembles.

</DOC>
<DOC>
<DOCNO> 150445 </DOCNO>
D-branes in AdS_3xS^3xS^3xS^1


  We analyse the possible D-brane configurations in an AdS_3xS^3xS^3xS^1
background with a NS-NS B field, by using the boundary state formalism. We
study their geometry and we determine the fraction of spacetime supersymmetry
preserved by these solutions.

</DOC>
<DOC>
<DOCNO> 68841 </DOCNO>
Spectators effect in inclusive beauty decays


  I review the role of the spectator quarks effect in the inclusive beauty
decays. The evaluation of the expectation values of four-quark operators
between hadronic states and its consequences are discussed.

</DOC>
<DOC>
<DOCNO> 100214 </DOCNO>
Generalized toric varieties for simple non-rational convex polytopes


  We call complex quasifold of dimension k a space that is locally isomorphic
to the quotient of an open subset of the space C^k by the holomorphic action of
a discrete group; the analogue of a complex torus in this setting is called a
complex quasitorus. We associate to each simple polytope, rational or not, a
family of complex quasifolds having same dimension as the polytope, each
containing a dense open orbit for the action of a suitable complex quasitorus.
We show that each of these spaces M is diffeomorphic to one of the symplectic
quasifolds defined in http://arXiv.org/abs/math:SG/9904179, and that the
induced symplectic structure is compatible with the complex one, thus defining
on M the structure of a Kaehler quasifold. These spaces may be viewed as a
generalization of the toric varieties that are usually associated to those
simple convex polytopes that are rational.

</DOC>
<DOC>
<DOCNO> 71843 </DOCNO>
CKM matrix: the `over-consistent' picture of the unitarity triangle


  In presenting an up-to-date account of the experimental knowledge of the CKM
matrix, special emphasis is placed on the exceptional degree of consistency
shown by the current Standard Model determination of the unitarity triangle;
some implications in the question of how the theoretical nature of the dominant
uncertainties affects the Standard Model predictions are discussed. Recent
experimental results include improved determinations of |V_{cb}| by OPAL and
CLEO, the confirmation of rare (charmless hadronic and electromagnetic penguin)
B decays and preliminary sin(2 beta) measurements by BaBar and Belle (new world
average: sin(2 beta) = 0.48 +0.22 -0.24). The updated constraints lead to the
Standard Model predictions sin(2 beta) = 0.68 +/- 0.03(exp) +/- 0.04(th), sin(2
alpha) = -0.43 +/- 0.15(exp) +/- 0.20(th), gamma = 56 +/- 5(exp)(+5 -6)(th)
deg, Delta m_{Bs} = 16.2 (+2.7 -0.3)(exp)(+1.5 -1.0)(th) ps^{-1}.

</DOC>
<DOC>
<DOCNO> 119697 </DOCNO>
Regimes Of Helium Burning


  The burning regimes encountered by laminar deflagrations and ZND detonations
propagating through helium-rich compositions in the presence of buoyancy-driven
turbulence are analyzed. Particular attention is given to models of X-ray
bursts which start with a thermonuclear runaway on the surface of a neutron
star, and the thin shell helium instability of intermediate-mass stars. In the
X-ray burst case, turbulent deflagrations propagating in the lateral or radial
directions encounter a transition from the distributed regime to the flamlet
regime at a density of 10^8 g cm^{-3}. In the radial direction, the purely
laminar deflagration width is larger than the pressure scale height for
densities smaller than 10^6 g cm^{-3}. Self-sustained laminar deflagrations
travelling in the radial direction cannot exist below this density. Similarily,
the planar ZND detonation width becomes larger than the pressure scale height
at 10^7 g cm^{-3}, suggesting that a steady-state, self-sustained detonations
cannot come into existance in the radial direction. In the thin helium shell
case, turbulent deflagrations travelling in the lateral or radial directions
encounter the distributed regime at densities below 10^7 g cm^{-3}, and the
flamelet regime at larger densities. In the radial direction, the purely
laminar deflagration width is larger than the pressure scale height for
densities smaller than 10^4 g cm^{-3}, indicating that steady-state laminar
deflagrations cannot form below this density. The planar ZND detonation width
becomes larger than the pressure scale height at 5 10^4 g cm^{-3}, suggesting
that steady-state, self-sustained detonations cannot come into existance in the
radial direction.

</DOC>
<DOC>
<DOCNO> 121977 </DOCNO>
The Distribution of Water Emission in M17SW


  We present a 17-point map of the M17SW cloud core in the 1_{10}-1_{01}
transition of ortho-water at 557 GHz obtained with the Submillimeter Wave
Astronomy Satellite. Water emission was detected in 11 of the 17 observed
positions. The line widths of the water emission vary between 4 and 9 km
s^{-1}, and are similar to other emission lines that arise in the M17SW core. A
direct comparison is made between the spatial extent of the water emission and
the ^{13}CO J = 5\to4 emission; the good agreement suggests that the water
emission arises in the same warm, dense gas as the ^{13}CO emission. A spectrum
of the H_2^{18}O line was also obtained at the center position of the cloud
core, but no emission was detected. We estimate that the average abundance of
ortho-water relative to H_2 within the M17 dense core is approximately
1x10^{-9}, 30 times smaller than the average for the Orion core. Toward the H
II region/molecular cloud interface in M17SW the ortho-water abundance may be
about 5 times larger than in the dense core.

</DOC>
<DOC>
<DOCNO> 170158 </DOCNO>
Pauli Exchange and Quantum Error Correction


  In many physically realistic models of quantum computation, Pauli exchange
interactions cause a special type of two-qubit errors, called exchange errors,
to occur as a first order effect of couplings within the computer. We discuss
the physical mechanisms behind exchange errors and codes designed to explicitly
deal with them.

</DOC>
<DOC>
<DOCNO> 12946 </DOCNO>
Theory of Tunneling Spectroscopy in Ferromagnetic Nanoparticles


  We present a theory of the low-energy excitations of a ferromagnetic metal
nanoparticle. In addition to the particle-hole excitations, which occur in a
paramagnetic metal nanoparticle, we predict a branch of excitations involving
the magnetization-orientation collective coordinate. Tunneling matrix elements
are in general sizable for several different collective states associated with
the same band configuration. We point out that the average change in ground
state spin per added electron differs from non-interacting quasiparticle
expectations, and that the change in the spin-polarization, due to Zeeman
coupling, is strongly influenced by Coulomb blockade physics.

</DOC>
<DOC>
<DOCNO> 9719 </DOCNO>
Critical behaviour of the 1d annihilation fission process 2A->0, 2A->3A


  Numerical simulations and cluster mean-field approximations with coherent
anomaly extrapolation show that the critical line of the 1d annihilation
fission process is separated into two regions. In both the small and high
diffusion cases the critical behavior is different from the well known
universality classes of non-equilibrium phase transitions to absorbing states.
The high diffusion region seems to be well described by the cyclically coupled
directed percolation and annihilating random walk. Spreading exponents show
non-universal behavior.

</DOC>
<DOC>
<DOCNO> 121534 </DOCNO>
Optical photometry of the PSR B0656+14 and its neighborhood


  We present the results of the broad-band photometry of the nearby middle-aged
radio pulsar PSR B0656+14 and its neighborhood obtained with the 6-meter
telescope of the SAO RAS and with the Hubble Space Telescope. The broad-band
spectral flux $F_\nu$ of the pulsar decreases with increasing frequency in the
near-IR range and increases with frequency in the near-UV range. The increase
towards UV can be naturally interpreted as the Rayleigh-Jeans tail of the soft
thermal component of the X-ray spectrum emitted from the surface of the cooling
neutron star. Continuation of the power-law component, which dominates in the
high-energy tail of the X-ray spectrum, to the IR-optical-UV frequencies is
consistent with the observed fluxes. This suggests that the non-thermal pulsar
radiation may be of the same origin in a broad frequency range from IR to hard
X-rays. We also studied 4 objects detected in the pulsar's 5" neighborhood.

</DOC>
<DOC>
<DOCNO> 169951 </DOCNO>
Introduction to Quantum Algorithms


  These notes discuss the quantum algorithms we know of that can solve problems
significantly faster than the corresponding classical algorithms. So far, we
have only discovered a few techniques which can produce speed up versus
classical algorithms. It is not clear yet whether the reason for this is that
we do not have enough intuition to discover more techniques, or that there are
only a few problems for which quantum computers can significantly speed up the
solution.

</DOC>
<DOC>
<DOCNO> 12304 </DOCNO>
Dual Nature of the Electronic Structure of the Stripe Phase


  High resolution angle-resolved photoemission measurements have been carried
out on (La_1.4-xNd_0.6Sr_x)CuO_4, a model system with static stripes, and
(La_1.85Sr_0.15)CuO_4, a high temperature superconductor (T_c=40K) with dynamic
stripes. In addition to the straight segments near (pi, 0) and (0, pi)
antinodal regions, we have identified the existence of nodal spectral weight
and its associated Fermi surface in the electronic structure of both systems.
The ARPES spectra in the nodal region show well-defined Fermi cut-off,
indicating a metallic character of this charge-ordered state. This observation
of nodal spectral weight, together with the straight segments near antinodal
regions, reveals dual nature of the electronic structure of the stripes due to
the competition of order and disorder.

</DOC>
<DOC>
<DOCNO> 121135 </DOCNO>
How young are early-type cluster galaxies ? Quantifying the young


  We present a new method of quantifying the mass fraction of young stars in
galaxies by analyzing near-ultraviolet (NUV)-optical colors. We focus our
attention on early-type cluster galaxies, whose star formation history is at
present undetermined. Rest-frame NUV (F300W) and optical (F702W) images of
cluster Abell 851 (z=0.41) using HST/WFPC2 allow us to determine a NUV-optical
color-magnitude relation, whose slope is incompatible with a monolithic
scenario for star formation at high redshift. A degeneracy between a young
stellar component and its fractional mass contribution to the galaxy is found,
and a photometric analysis comparing the data with the predictions for a simple
two-stage star formation history is presented. The analysis shows that some of
the early-type galaxies may have fractions higher than 10% of the total mass
content in stars formed at z~0.5. An increased scatter is found in the
color-magnitude relation at the faint end, resulting in a significant fraction
of faint blue early-type systems. This would imply that less massive galaxies
undergo more recent episodes of star formation, and this can be explained in
terms of a positive correlation between star formation efficiency and
luminosity.

</DOC>
<DOC>
<DOCNO> 85454 </DOCNO>
Energy Distribution of a Charged Regular Black Hole


  We calculate the energy distribution of a charged regular black hole by using
the energy-momentum complexes of Einstein and M{\o}ller.

</DOC>
<DOC>
<DOCNO> 117949 </DOCNO>
Quasar Clustering and the Lifetime of Quasars


  Although the population of luminous quasars rises and falls over a period of
10^9 years, the typical lifetime of individual quasars is uncertain by several
orders of magnitude. We show that quasar clustering measurements can
substantially narrow the range of possible lifetimes with the assumption that
luminous quasars reside in the most massive host halos. If quasars are
long-lived, then they are rare phenomena that are highly biased with respect to
the underlying dark matter, while if they are short-lived they reside in more
typical halos that are less strongly clustered. For a given quasar lifetime, we
calculate the minimum host halo mass by matching the observed space density of
quasars, using the Press-Schechter approximation. We use the results of Mo &
White to calculate the clustering of these halos, and hence of the quasars they
contain, as a function of quasar lifetime. A lifetime of t_Q = 4 x 10^7 years,
the e-folding timescale of an Eddington luminosity black hole with accretion
efficiency eps=0.1, corresponds to a quasar correlation length r_0 ~ 10 Mpc/h
in low-density cosmological models at z=2-3; this value is consistent with
current clustering measurements, but these have large uncertainties.
High-precision clustering measurements from the 2dF and Sloan quasar surveys
will test our key assumption of a tight correlation between quasar luminosity
and host halo mass, and if this assumption holds then they should determine t_Q
to a factor of three or better. An accurate determination of the quasar
lifetime will show whether supermassive black holes acquire most of their mass
during high-luminosity accretion, and it will show whether the black holes in
the nuclei of typical nearby galaxies were once the central engines of
high-luminosity quasars.

</DOC>
<DOC>
<DOCNO> 69501 </DOCNO>
Effects of the Fourth Generation on $\Delta M_{B_{d,s}}$ in $B^0-\bar


  We investigate the mass differences $\Delta M_{B_{d,s}}$ in the mixing
$B^0_{d,s}-\bar B^0_{d,s}$ with a new up-like quark $t^{\prime}$ in the
sequential fourth generation model. We give the basic formulae for $\Delta
M_{B_{d,s}}$ in this model and obtain two kinds of numerical results of $\Delta
M_{B_{s}}$ which is the function of $m_{t^{\prime}}$. We find that one of our
results can satisfy the present experimental low bound of $\Delta M_{B_s}$. We
also get the constraints of the fourth generation CKM factor
$V^{*}_{t^{'}b}V_{t^{'}d}$, which is the function of $t^{'}$, from the
experimental measurements of $\Delta M_{B_d}$. Thus, $\Delta M_{B_{d,s}}$
provide a possible test of the fourth generation and give a signal of the new
physics.

</DOC>
<DOC>
<DOCNO> 170516 </DOCNO>
Beyond Stabilizer Codes I: Nice Error Bases


  Nice error bases have been introduced by Knill as a generalization of the
Pauli basis. These bases are shown to be projective representations of finite
groups. We classify all nice error bases of small degree, and all nice error
bases with abelian index groups. We show that in general an index group of a
nice error basis is necessarily solvable.

</DOC>
<DOC>
<DOCNO> 84686 </DOCNO>
On the existence and convergence of polyhomogeneous expansions of


  The convergence of polyhomogeneous expansions of zero-rest-mass fields in
asymptotically flat spacetimes is discussed. An existence proof for the
asymptotic characteristic initial value problem for a zero-rest-mass field with
polyhomogeneous initial data is given. It is shown how this non-regular problem
can be properly recast as a set of regular initial value problems for some
auxiliary fields. The standard techniques of symmetric hyperbolic systems can
be applied to these new auxiliary problems, thus yielding a positive answer to
the question of existence in the original problem.

</DOC>
<DOC>
<DOCNO> 100118 </DOCNO>
Eisenstein series twisted by modular symbols for the group SL(n)


  We define Eisenstein series twisted by modular symbols on the group SL(n),
generalizing a construction of the first author. We show that, in the case of
series attached to the minimal parabolic subgroup, our series converges for all
points in a suitable cone. We conclude with examples for SL(2) and SL(3).

</DOC>
<DOC>
<DOCNO> 100539 </DOCNO>
A four parameter generalization of Gollnitz's (BIG) partition theorem


  We announce a new four parameter partition theorem from which the (big)
theorem of Gollnitz follows by setting any one of the parameters equal to 0.
This settles a problem of Andrews who asked whether there exists a result that
goes beyond the partition theorem of Gollnitz. We state a four parameter
q-series identity (key identity) which is the generating function form of this
theorem. In a subsequent paper, the proof of the new four parameter key
identity will be given.

</DOC>
<DOC>
<DOCNO> 68439 </DOCNO>
Predictive Grand Unified Textures for Quark and Neutrino Masses and


  We propose new textures for the fermion Yukawa matrices which are
generalizations of the so-called Stech ansatz. We discuss how these textures
can be realized in supersymmetric grand unified models with horizontal symmetry
SU(3)_H among the fermion generations. In this framework the mass and mixing
hierarchy of fermions (including neutrinos) can emerge in a natural way. We
emphasize the central role played by the SU(3)_H adjoint Higgs field which
reduces SU(3)_H to U(2)_H at the GUT scale. A complete SO(10)\times SU(3)_H
model is presented in which the desired Yukawa textures can be obtained by
symmetry reasons. The phenomenological implications of these textures are
thoroughly investigated. Among various realistic possibilities for the Clebsch
factors between the quark and lepton entries, we find three different solutions
which provide excellent fits of the quark masses and CKM mixing angles.
Interestingly, all these solutions predict the correct amount of CP violation
via the CKM mechanism, and, in addition, lead to an appealing pattern of the
neutrino masses and mixing angles. In particular, they all predict nearly
maximal 23 mixing and small 12 mixing in the lepton sector, respectively in the
range needed for the explanation of the atmospheric and solar neutrino anomaly.

</DOC>
<DOC>
<DOCNO> 122353 </DOCNO>
A New Radio Continuum Survey of the Sky at 1465 MHz between declinations


  We have mapped the total sky brightness at 1465 MHz in two adjacent 60-degree
declination bands with the portable 5.5-m parabolic reflector of the Galactic
Emission Mapping (GEM) project, an on-going international collaboration to
survey the radio continuum of the sky in decimeter and centimeter wavelengths.
The observations were conducted from two locations, one in the USA and the
other in Brazil, using a novel instrumental approach to overcome the well-known
shortcomings of survey experiments. Our strategy consists of a 1-rpm rotating
dish to circularly scan the sky at 30 degrees from zenith. The dish uses a
rim-halo to re-direct the spillover sidelobes of its backfire helical feed
toward the sky and the entire assembly has been enclosed inside a wire mesh
ground shield in order to minimize and level out the contamination from the
ground. The diffraction characteristics of this set-up have been succesfully
modelled and undesired systematic striping across the observed bands has been
carefully removed by a baseline propagation method which exploits the
time-forward and time-backward intersections of the circular scans. The map
displays nearly 300 hours of our best quality data taken with a HPBW of 5.4
degrees at a sensitivity of 20 mK.

</DOC>
<DOC>
<DOCNO> 116565 </DOCNO>
Time symmetric action-at-a-distance electrodynamics and the structure of


  This paper begins with a critical analysis of the concept of 'material point
particle'. We argue that this concept is incompatible with the force laws of
action-at-a-distance electrodynamics, and we suggest that the trajectory of a
particle (the world-line) should be looked upon as a string in static
equilibrium. By complementing our model with a time symmetric interaction law,
we are led to a straightforward derivation of the principles underlying the
electromagnetic interaction between two uniformly moving charged particles. An
extension of our theory to the case of particles in arbitrary motion shows that
we have to modify Maxwell's equations of the microscopic electromagnetic field,
in order to accommodate a field-strength tensor which is no longer
antisymmetric. It is further argued that the radiation reaction force gives
another example of a 4-force which is not orthogonal to the 4-velocity, thus
leading to a variable rest mass. The variation of the rest mass is then
discussed from the point of view of the equivalence principle of general
relativity, and we end up with a theoretical derivation of the homogenous
Maxwell's equations.

</DOC>
<DOC>
<DOCNO> 70405 </DOCNO>
Electroweak baryogenesis in the standard model with strong hypermagnetic


  We show that in the presence of large scale primordial hypermagnetic fields,
it is possible to generate a large amount of CP violation to explain the baryon
to entropy ratio during the electroweak phase transition within the standard
model. The mechanism responsible for the existence of a CP violating asymmetry
is the chiral nature of the fermion coupling to the background field in the
symmetric phase which can be used to construct two-fermion interference
processes in analogy to the Bohm-Aharanov effect. We estimate that for strong
hypermagnetic fields B_Y=(0.3-0.5)T^2 the baryon to entropy ratio can be
rho_B/s=(3 - 6)X10^-11 for slowly expanding bubble walls.

</DOC>
<DOC>
<DOCNO> 83372 </DOCNO>
Automatic Extraction of Subcategorization Frames for Czech


  We present some novel machine learning techniques for the identification of
subcategorization information for verbs in Czech. We compare three different
statistical techniques applied to this problem. We show how the learning
algorithm can be used to discover previously unknown subcategorization frames
from the Czech Prague Dependency Treebank. The algorithm can then be used to
label dependents of a verb in the Czech treebank as either arguments or
adjuncts. Using our techniques, we ar able to achieve 88% precision on unseen
parsed text.

</DOC>
<DOC>
<DOCNO> 11410 </DOCNO>
The relationship between extremum statistics and universal fluctuations


  The normalized probability density function (PDF) of global measures of a
large class of highly correlated systems has previously been demonstrated to
fall on a single non-Gaussian "universal" curve. We derive the functional form
of the "global" PDF in terms of the "source" PDF of the individual events in
the system. A single parameter distinguishes the global PDF and is related to
the exponent of the source PDF. When normalized, the global PDF is shown to be
insensitive to this parameter and importantly we obtain the previously
demonstrated "universality" from an uncorrelated Gaussian source PDF. The
second and third moments of the global PDF are more sensitive, providing a
powerful tool to probe the degree of complexity of physical systems.

</DOC>
<DOC>
<DOCNO> 120078 </DOCNO>
The iron abundance in hot central stars of planetary nebulae derived


  We present the first attempt to determine the iron abundance in hot central
stars of planetary nebulae. We perform an analysis with fully metal-line
blanketed NLTE model atmospheres for a sample of ten stars (T_eff >= 70.000 K)
for which high-resolution UV spectra are available from the IUE archive. In all
cases lines of Fe VI or Fe VII can be identified. As a general trend, the iron
abundance appears to be subsolar by 0.5-1 dex, however, the S/N of the IUE
spectra is not sufficient to exclude a solar abundance in any specific case.
Improved spectroscopy by either FUSE or HST is necessary to verify the
possibility of a general iron deficiency in central stars. The suspected
deficiency may be the result of gravitational settling in the case of three
high-gravity objects. For the other stars with low gravity and high luminosity
dust fractionation during the previous AGB phase is a conceivable origin.

</DOC>
<DOC>
<DOCNO> 170415 </DOCNO>
Optimal dense coding with mixed state entanglement


  I investigate dense coding with a general mixed state on the Hilbert space
$C^{d}\otimes C^{d}$ shared between a sender and receiver. The following result
is proved. When the sender prepares the signal states by mutually orthogonal
unitary transformations with equal {\it a priori} probabilities, the capacity
of dense coding is maximized. It is also proved that the optimal capacity of
dense coding $\chi ^{*}$ satisfies $E_{R}(\rho)\leq \chi ^{*}\leq E_{R}(\rho
)+\log_{2}d$, where $E_{R}(\rho)$ is the relative entropy of entanglement of
the shared entangled state.

</DOC>
<DOC>
<DOCNO> 119719 </DOCNO>
Transient Low-Mass X-Ray Binaries in Quiescence


  We summarize the quiescent X-ray observations of transient low-mass X-ray
binaries. These observations show that, in quiescence, binaries containing
black holes are fainter than those containing neutron stars. This has triggered
a number of theoretical ideas about what causes the quiescent X-ray emission.
For black hole binaries, the options are accretion onto the black hole or
coronal emission from the rapidly rotating stellar companion. There are more
possibilities for the neutron stars: accretion, thermal emission from the
surface or non-thermal emission from a ``turned-on'' radio pulsar. We review
recent theoretical work on these mechanisms and note where current observations
can distinguish between them. We highlight the re-analysis of the quiescent
neutron star emission by Rutledge and collaborators that showed thermal
emission to be a predominant contributor in many of these systems. Our
knowledge of these binaries is bound to dramatically improve now that the
Chandra and XMM satellites are operating successfully,

</DOC>
<DOC>
<DOCNO> 118294 </DOCNO>
Changes in the long term intensity variations in Cyg X-2 and LMC X-3


  We report the detection of changes in the long-term intensity variations in
two X-ray binaries, Cyg X-2 and LMC X-3. In this work, we have used the
long-term light curves obtained with the All-Sky Monitors (ASMs) of the Rossi
X-Ray Timing Explorer (RXTE), Ginga, Ariel 5, and Vela 5B and the scanning
modulation collimator of HEAO 1. It is found that in the light curves of both
the sources, obtained with these instruments at various times over the last 30
years, more than one periodic or quasi-periodic component is always present.
The multiple prominent peaks in the periodograms have frequencies unrelated to
each other. In Cyg X-2, RXTE-ASM data show strong peaks at 40.4 and 68.8 days,
and Ginga-ASM data show strong peaks at 53.7 and 61.3 days. Multiple peaks are
also observed in LMC X-3. The various strong peaks in the periodograms of LMC
X-3 appear at 104, 169, and 216 days (observed with RXTE-ASM) and 105, 214, and
328 days (observed with Ginga-ASM). The present results, when compared with the
earlier observations of periodicities in these two systems, demonstrate the
absence of any stable long period. The 78 day periodicity detected earlier in
Cyg X-2 was probably due to the short time base in the RXTE data that were
used, and the periodicity of 198 days in LMC X-3 was due to a relatively short
duration of observation with HEAO 1.

</DOC>
<DOC>
<DOCNO> 71617 </DOCNO>
Solving the BFKL Equation with Running Coupling


  We describe a formalism for solving the BFKL equation with a coupling that
runs for momenta above a certain infrared cutoff. By suitably choosing matching
conditions proper account is taken of the fact that the BFKL diffusion implies
that the solution in the infrared (fixed coupling) regime depends upon the
solution in the ultraviolet (running coupling) regime and vice versa. Expanding
the BFKL kernel to a given order in the ratio of the transverse momenta allows
arbitrary accuracy to be achieved.

</DOC>
<DOC>
<DOCNO> 151953 </DOCNO>
Uniqueness of Tachyonic Solitons


  It has been conjectured that condensation of tachyons on a bosonic D-brane
gives rise to vacuum / soliton solutions which are independent of the initial
magnetic field on the D-brane. We present evidence for this conjecture using
results from two dimensional conformal field theory. In particular we identify
a continuous path in the configuration space of open string fields which
interpolates between D-brane configurations with two different quantized
magnetic flux.

</DOC>
<DOC>
<DOCNO> 121276 </DOCNO>
Environmental Effects on Gas and Galaxy Evolution in Clusters


  The cluster environment is the site of important transformations in galaxies
at a relatively recent cosmological epoch: the galactic morphological types and
star formation activity have evolved significantly during the last few Gyrs.
How is this related to the galactic gas content? The first part of this paper
briefly presents the optical observations of galaxies in distant clusters,
while the second part focuses on the link between the HI content and the star
formation activity, presenting the results of a multiwavelength study of the
cluster A2670 (z=0.08) where 42 galaxies have been detected in HI. We show the
star formation properties of the HI-normal and HI-deficient galaxies and
discuss their dependence on the location within the cluster. Finally, we
compare A2670 with clusters at intermediate redshift and with the Coma cluster.

</DOC>
<DOC>
<DOCNO> 12534 </DOCNO>
Thermodynamics of Crossover from Weak- to Strong-Coupling


  In this paper we study an evolution of low-temperature thermodynamical
quantities for an electron gas with a $ \delta $-function attraction as the
system crosses over from weak-coupling (BCS-type) to strong-coupling
(Bose-type) superconductivity in three and two dimensions.

</DOC>
<DOC>
<DOCNO> 119411 </DOCNO>
Radial velocities of pulsating subdwarf B stars: KPD 2109+4401 and PB


  High-speed spectroscopy of two pulsating subdwarf B stars, KPD 2109+4401 and
PB 8783, is presented. Radial motions are detected with the same frequencies as
reported from photometric observations and with amplitudes of ~2 km/sec in two
or more independent modes. These represent the first direct observations of
surface motion due to multimode non-radial oscillations in subdwarf B stars. In
the case of the sdB+F binary PB 8783, the velocities of both components are
resolved; high-frequency oscillations are found only in the sdB star and not
the F star. There also appears to be evidence for mutual motion of the binary
components. If confirmed, it implies that the F-type companion is >~1.2 times
more massive than the sdB star, while the amplitude of the F star acceleration
over 4 hours would constrain the orbital period to lie between 0.5 and 3.2d.

</DOC>
<DOC>
<DOCNO> 120718 </DOCNO>
Detection of X-ray Emission from Gravitationally Lensed Submillimeter


  We report the detection by Chandra of SMM J02399-0134 and SMM J02399-0136,
two distant (z=1.06 and z=2.81, respectively) submillimeter sources
gravitationally magnified by the galaxy cluster Abell 370. These are
high-significance (> 7-sigma) X-ray detections of the high-redshift
submillimeter source population. The X-ray positions are coincident with the
optical positions to within one arcsecond. The X-ray spectra, while of low
signal-to-noise ratio, are quite hard. Absorbed power law models with fixed
photon indices of $\Gamma=2.0$ imply local absorbing columns $>2 \times
10^{23}$ cm$^{-2}$ and unabsorbed luminosities $>10^{44}$ erg s$^{-1}$ in both
sources. These results imply that nuclear activity is responsible for the bulk
of the luminosity in SMM J02399-0134, and for at least 20% of the luminosity of
SMM J02399-0136, consistent with previous optical observations. We also place
an upper limit on the X-ray flux of a third submillimeter source, SMM
J02400-0134. Considered together with previously published Chandra upper limits
on X-ray flux from submillimeter sources, our results imply that
$20^{+30}_{-16}$ % of submillimeter sources exhibit X-ray emission from AGN
(90% confidence), consistent with expectations of their contribution to the
diffuse X-ray background.

</DOC>
<DOC>
<DOCNO> 70037 </DOCNO>
The initial gluon multiplicity in heavy ion collisions


  The initial gluon multiplicity per unit area per unit rapidity, dN/L^2/d\eta,
in high energy nuclear collisions, is equal to f_N (g^2\mu L) (g^2\mu)^2/g^2,
with \mu^2 proportional to the gluon density per unit area of the colliding
nuclei. For an SU(2) gauge theory, we compute f_N (g^2\mu L)=0.14\pm 0.01 for a
wide range in g^2\mu L. Extrapolating to SU(3), we predict dN/L^2/d\eta for
values of g^2\mu L in the range relevant to the Relativistic Heavy Ion Collider
and the Large Hadron Collider. We compute the initial gluon transverse momentum
distribution, dN/L^2/d^2 k_\perp, and show it to be well behaved at low
k_\perp.

</DOC>
<DOC>
<DOCNO> 151751 </DOCNO>
D-Branes and Scheme Theory


  In this highly speculative note we conjecture that it may be possible to
understand features of coincident D-branes, such as the appearance of enhanced
non-abelian gauge symmetry, in a purely geometric fashion, using a form of
geometry known as scheme theory. We give a very brief introduction to some
relevant ideas from scheme theory, and point out how these ideas work in
special cases.

</DOC>
<DOC>
<DOCNO> 101913 </DOCNO>
The Geometry of Autonomous Metrical Multi-Time Lagrange Space of


  The paper contains a geometrization of the autonomous multi-time Lagrangian
function of electrodynamics. We point out that this multi-time Lagrangian
function comes from electrodynamics and the theory of bosonic strings.

</DOC>
<DOC>
<DOCNO> 151385 </DOCNO>
Non-linear Vacuum Phenomena in Non-commutative QED


  We show that the classic results of Schwinger on the exact propagation of
particles in the background of constant field-strengths and plane waves can be
readily extended to the case of non-commutative QED. It is shown that
non-perturbative effects on constant backgrounds are the same as their
commutative counterparts, provided the on-shell gauge invariant dynamics is
referred to a non-perturbatively related space-time frame. For the case of the
plane wave background, we find evidence of the effective extended nature of
non-commutative particles, producing retarded and advanced effects in
scattering. Besides the known `dipolar' character of non-commutative neutral
particles, we find that charged particles are also effectively extended, but
they behave instead as `half-dipoles'.

</DOC>
<DOC>
<DOCNO> 99352 </DOCNO>
Continued fractions and Catalan problems


  We find a generating function expressed as a continued fraction that
enumerates ordered trees by the number of vertices at different levels. Several
Catalan problems are mapped to an ordered-tree problem and their generating
functions also expressed as a continued fraction. Among these problems is the
enumeration of (132)-pattern avoiding permutations that have a given number of
increasing patterns of length k. This extends and illuminates a result of
Robertson, Wilf and Zeilberger for the case k=3.

</DOC>
<DOC>
<DOCNO> 101293 </DOCNO>
Higher order intersection numbers of 2-spheres in 4-manifolds


  This is the beginning of an obstruction theory for deciding whether a map
f:S^2 --> X^4 is homotopic to a topologically flat embedding, in the presence
of fundamental group and in the absence of dual spheres. The first obstruction
is Wall's self-intersection number mu(f) which tells the whole story in higher
dimensions. Our second order obstruction tau(f) is defined if mu(f) vanishes
and has formally very similar properties, except that it lies in a quotient of
the group ring of two copies of pi_1(X) modulo S_3-symmetry (rather then just
one copy modulo S_3-symmetry). It generalizes to the non-simply connected
setting the Kervaire-Milnor invariant which corresponds to the Arf-invariant of
knots in 3-space.
  We also give necessary and sufficient conditions for moving three maps
f_1,f_2,f_3:S^2 --> X^4 to a position in which they have disjoint images. Again
the obstruction lambda(f_1,f_2,f_3) generalizes Wall's intersection number
lambda(f_1,f_2) which answers the same question for two spheres but is not
sufficient (in dimension 4) for three spheres. In the same way as intersection
numbers correspond to linking numbers in dimension 3, our new invariant
corresponds to the Milnor invariant mu(1,2,3), generalizing the Matsumoto
triple to the non simply-connected setting.

</DOC>
<DOC>
<DOCNO> 152212 </DOCNO>
Spin-statistics transmutation in relativistic quantum field theories of


  We analyse spin and statistics of quantum dyon fields, i.e. fields carrying
both electric and magnetic charge, in 3+1 space-time dimensions. It has been
shown long time ago that, at the quantum mechanical level, a composite dyon
made out of a magnetic pole of charge g and a particle of electric charge e
possesses half-integral spin and fermionic statistics, if the constituents are
bosons and the Dirac quantization condition $eg=2\pi n$ holds, with n odd. This
phenomenon is called spin-statistics transmutation. We show that the same
phenomenon occurs at the quantum field theory level for an elementary dyon.
This analysis requires the construction of gauge invariant charged dyon fields.
Dirac's proposal for such fields, relying on a Coulomb-like photon cloud, leads
to quantum correlators exhibiting an unphysical dependence on the Dirac-string.
Recently Froehlich and Marchetti proposed a recipe for charged dyon fields,
based on a sum over Mandelstam-strings, which overcomes this problem. Using
this recipe we derive explicit expressions for the quantum field theory
correlators and we provide a proof of the occurrence of spin-statistics
transmutation. The proof reduces to a computation of the self-linking numbers
of dyon worldlines and Mandelstam strings, projected on a fixed time
three-space. Dyon composites are also analysed. The transmutation discussed in
this paper bares some analogy with the appearance of anomalous spin and
statistics for particles or vortices in Chern-Simons theories in 2+1
dimensions. However, peculiar features appear in 3+1 dimensions e.g. in the
spin addition rule.

</DOC>
<DOC>
<DOCNO> 70321 </DOCNO>
Bekenstein model and the time variation of the strong coupling constant


  We propose to generalize Bekenstein model for the time variation of the fine
structure "constant" $\alpha_{em}$ to QCD strong coupling constant $\alpha_S$.
We find that, except for a ``fine tuned'' choice of the free parameters, the
extension can not be performed trivially without being in conflict with
experimental constraints and this rules out $\alpha_S$ variability. This is due
largely to the huge numerical value of the QCD vacuum gluon condensate when
compared to the matter density of the universe.

</DOC>
<DOC>
<DOCNO> 150900 </DOCNO>
Topological Mass Generation as an Interference Phenomenon


  It is proposed a new mechanism for the phenomenon of topological mass
generation in three spacetime dimensions as the result of the interference of
two opposite massless chiral modes. This mechanism, already used to produce the
massive vectorial mode of the 2D Schwinger model, is here exploited to produce
the gauge invariant massive mode of the Maxwell-Chern-Simons theory. Moreover
the procedure is clearly dimensionally independent: a new chiral boson action
is proposed for odd and even dimensional space-times to be used as the basic
building blocks of the interference schemes. This is a new result that extends
the two-dimensional Floreanini-Jackiw action to higher dimensional spaces and
is in clear contrast with the twice odd dimensional chiral form extensions.

</DOC>
<DOC>
<DOCNO> 69488 </DOCNO>
The d' dibaryon in the quark-delocalization, color-screening model


  We study the questions of the existence and mass of the proposed $d'
(IJ^P=00^-)$ dibaryon in the quark-delocalization, color-screening model
(QDCSM). The transformation between physical and symmetry bases has been
extended to the cases beyond the SU(2) orbital symmetry. Using parameters fixed
by baryon properties and $NN$ scattering, we find a mild attraction in the
$IJ^P=00^-$ channel, but it is not strong enough to form a deeply bound state
as proposed for the $d'$ state. Nor does the (isospin) I=2 N$\Delta$
configuration have a deeply bound state. These results show that if a narrow
dibaryon $d'$ state does exist, it must have a more complicated structure.

</DOC>
<DOC>
<DOCNO> 116560 </DOCNO>
Rotating Band Pion Production Targets for Muon Colliders and Neutrino


  An update is presented on a conceptual design for a pion production target
station using a rotating cupronickel band and that was originally proposed for
use at a muon collider facility with a 4 MW pulsed proton beam. After reviewing
the salient design features and motivations for this target, ongoing studies
are described that are attempting to benchmark the thermal stresses and
radiation damage on the target band using data from the Fermilab antiproton
source and other operating targets. Possible parameter optimizations and
alternative technologies for the rotating band are surveyed, including
discussion on the the various proton beam parameters that might be encountered
for rotating band targets at either muon colliders or neutrino factories.
Finally, an outline is proposed for a possible R&D path towards capability for
the actual construction of rotating band pion production targets.

</DOC>
<DOC>
<DOCNO> 120423 </DOCNO>
The Cosmological Angular Momentum Problem of Low-Mass Disk Galaxies


  The rotational properties of the visible and dark components of low-mass disk
galaxies (vrot<=100 km/s) are investigated using the Swaters sample. The
rotational parameter lambda'=lambda_DM*(j_d/m_d) is determined, where lambda_DM
is the dark halo spin parameter and j_d/m_d is the ratio between the specific
angular momentum of the disk and that of the dark halo. The distribution of
lambda' is in excellent agreement with cosmological predictions of hierarchical
clustering if j_d/m_d=1, that is if the protogalactic gas did not loose a
significant amount of specific angular momentum due to dynamical friction. This
result is in disagreement with current cosmological Nbody/SPH simulations where
the baryonic component looses 90% of its specific angular momentum while
settling into the equatorial plane. The Swaters sample also shows a
surprisingly strong correlation between lambda' and the baryonic mass fraction
m_d: lambda'=0.4 m_d**0.6. This correlation can be explained if the total
amount of gas in protogalaxies is a universal fraction of their dark matter
mass, of order 10%, and if the variation in m_d is a result of the fact that
only the inner parts of the primordial gas distribution managed to form a
visible disk component. In this case the specific angular momentum of the gas
out of which the disk formed is a factor of 2.75 larger than that of the dark
halo, which would require a yet unknown spin-up process for the visible
baryonic component.

</DOC>
<DOC>
<DOCNO> 71333 </DOCNO>
How Hard Are the Form Factors in Hadronic Vertices with Heavy Mesons?


  The $ND\Lambda_c$ and $ND^*\Lambda_c$ form factors are evaluated in a full
QCD sum rule calculation. We study the double Borel sum rule for the three
point function of one meson one nucleon and one $\Lambda_c$ current up to order
six in the operator product expansion. The double Borel transform is performed
with respect to the nucleon and $\Lambda_c$ momenta, and the form factor is
evaluated as a function of the momentum $Q^2$ of the heavy meson. These form
factors are relevant to evaluate the charmonium absorption cross section by
hadrons. Our results are compatible with constant form factors in these
vertices.

</DOC>
<DOC>
<DOCNO> 39920 </DOCNO>
5-10 GeV Neutrinos from Gamma-Ray Burst Fireballs


  A gamma-ray burst fireball is likely to contain an admixture of neutrons, in
addition to protons, in essentially all progenitor scenarios. Inelastic
collisions between differentially streaming protons and neutrons in the
fireball produce muon neutrinos (antineutrinos) of ~ 10 GeV as well as electron
neutrinos (antineutrinos) of ~ 5 GeV, which could produce ~ 7 events/year in
kilometer cube detectors, if the neutron abundance is comparable to that of
protons. Photons of ~ 10 GeV from pi-zero decay and ~ 100 MeV electron
antineutrinos from neutron decay are also produced, but will be difficult to
detect. Photons with energies < 1 MeV from shocks following neutron decay
produce a characteristic signal which may be distinguishable from the
proton-related MeV photons.

</DOC>
<DOC>
<DOCNO> 123212 </DOCNO>
Substructure and dynamics of the Fornax Cluster


  We present the first dynamical analysis of a galaxy cluster to include a
large fraction of dwarf galaxies. Our sample of 108 Fornax Cluster members
measured with the UK Schmidt Telescope FLAIR-II spectrograph contains 55 dwarf
galaxies (15.5>bj>18.0 or -16>Mb>-13.5). Halpha emission shows that 36+/-8 per
cent of the dwarfs are star-forming, twice the fraction implied by
morphological classifications. The total sample has a mean velocity of
1493+/-36 km/s and a velocity dispersion of 374+/-26 km/s. The dwarf galaxies
form a distinct population: their velocity dispersion (429+/-41 km/s) is larger
than that of the giants (308+/-30 km/s) at the 98 per cent confidence level.
This suggests that the dwarf population is dominated by infalling objects
whereas the giants are virialized.
  The Fornax system has two components; the main Fornax Cluster centered on NGC
1399 with mean velocity 1478 km/s and velocity dispersion 370 km/s, and a
subcluster centered 3 degrees to the south-west including NGC 1316 with mean
velocity 1583 km/s and velocity dispersion 377 km/s. This partition is
preferred over a single cluster at the 99 per cent confidence level. The
subcluster, a site of intense star formation, is bound to Fornax and probably
infalling towards the cluster core for the first time. We discuss the
implications of this substructure for distance estimates of the Fornax Cluster.

</DOC>
<DOC>
<DOCNO> 12643 </DOCNO>
Gauge factor enhancement driven by heterogeneity in thick-film resistors


  We present a simple picture of the gauge factor (GF) enhancement in highly
heterogeneous materials such as thick-film resistors. We show that when the
conducting phase is stiffer than the insulating one, the local strains within
this latter are enhanced with respect to the averaged macroscopic strain.
Within a simple model of electron tunneling processes, we show that the
enhanced local strain leads to values of GF higher than those expected for a
homogeneous system. Moreover we provide formulas relating the enhancement of GF
to the elastic and microstructural characteristics of TFRs.

</DOC>
<DOC>
<DOCNO> 100647 </DOCNO>
Induced corepresentations of locally compact quantum groups


  We introduce the construction of induced corepresentations in the setting of
locally compact quantum groups and prove that the resulting induced
corepresentations are unitary under some mild integrability condition. We also
establish a quantum analogue of the classical bijective correspondence between
quasi-invariant measures and certain measures on the larger locally compact
group.

</DOC>
<DOC>
<DOCNO> 8762 </DOCNO>
Diagonalization of a bosonic quadratic form using CCM: Application on a


  While the diagonalization of a quadratic bosonic form can always be done
using a Bogoliubov transformation, the practical implementation for systems
with a large number of different bosons is a tedious analytical task. Here we
use the coupled cluster method (CCM) to exactly diagonalise such complicated
quadratic forms. This yields to a straightforward algorithm which can easily be
implemented using computer algebra even for a large number of different bosons.
We apply this method on a Heisenberg system with two interpenetrating square
lattice antiferromagnets, which is a model for the quasi 2D antiferromagnet
Ba_2Cu_3O_4Cl_2. Using a four-magnon spin wave approximation we get a
complicated Hamiltonian with four different bosons, which is treated with CCM.
Results are presented for magnetic ground state correlations.

</DOC>
<DOC>
<DOCNO> 67870 </DOCNO>
Supersymmetry in Particle Physics: The Renormalization Group Viewpoint


  An attempt is made to present modern hopes to find manifestation of
supersymmetry, a new symmetry that relates bosons and fermions, in particle
physics from the point of view of renormalization group flow. The Standard
Model of particle interactions is briefly reviewed, the main notions of
supersymmetry are introduced. In more detail the RG flow in the Minimal
Supersymmetric Standard Model is considered. Predictions of particle spectrum
are obtained based on the RG fixed points.

</DOC>
<DOC>
<DOCNO> 99361 </DOCNO>
An Algebraic Duality Theory for Multiplicative Unitaries


  Multiplicative Unitaries are described in terms of a pair of commuting shifts
of relative depth two. They can be generated from ambidextrous Hilbert spaces
in a tensor C*-category. The algebraic analogue of the Takesaki-Tatsuuma
Duality Theorem characterizes abstractly C*-algebras acted on by unital
endomorphisms that are intrinsically related to the regular representation of a
multiplicative unitary. The relevant C*-algebras turn out to be simple and
indeed separable if the corresponding multiplicative unitaries act on a
separable Hilbert space. A categorical analogue provides internal
characterizations of minimal representation categories of a multiplicative
unitary. Endomorphisms of the Cuntz algebra related algebraically to the
grading are discussed as is the notion of braided symmetry in a tensor
C*-category.

</DOC>
<DOC>
<DOCNO> 151971 </DOCNO>
Brane-Antibrane Systems on Calabi-Yau Spaces


  We propose a correspondence between brane-antibrane systems and stable
triples (E_1,E_2,T), where E_1,E_2 are holomorphic vector bundles and the
tachyon T is a map between them. We demonstrate that, under the assumption of
holomorphicity, the brane-antibrane field equations reduce to a set of vortex
equations, which are equivalent to the mathematical notion of stability of the
triple. We discuss some examples and show that the theory of stable triples
suggests a new notion of BPS bound states and stability, and curious relations
between brane-antibrane configurations and wrapped branes in higher dimensions.

</DOC>
<DOC>
<DOCNO> 100602 </DOCNO>
The Yang-Mills Measure in the Kauffman Bracket Skein Module


  For each closed, orientable surface F, we construct a local, diffeomorphism
invariant trace on the Kauffman bracket skein module K_t(F x [0,1]). The trace
is defined when |t| is neither 0 nor 1, and at certain roots of unity. At t = -
1, the trace is integration against the symplectic measure on the SU(2)
character variety of the fundamental group of F.

</DOC>
<DOC>
<DOCNO> 120737 </DOCNO>
Binary quasars


  Quasar pairs are either physically distinct binary quasars or the result of
gravitational lensing. The majority of known pairs are in fact lenses, with a
few confirmed as binaries, leaving a population of objects that have not yet
been successfully classified. Building on the arguments of Kochanek, Falco &
Munoz (1999), it is shown that there are no objective reasons to reject the
binary interpretation for most of these. In particular, the similarity of the
spectra of the quasar pairs appears to be an artifact of the generic nature of
quasar spectra. The two ambiguous pairs discovered as part of the Large Bright
Quasar Survey (Q 1429-053 and Q 2153-0256) are analysed using principle
components analysis, which shows that their spectral similarities are not
greater than expected for a randomly chosen pair of quasars from the survey.
The assumption of the binary hypothesis allows the dynamics, time-scales and
separation distribution of binary quasars to be investigated and constrained.
The most plausible model is that the quasars' activity is triggered by tidal
interactions in a galatic merger, but that the (re-)activation of the galactic
nuclei occurs quite late in the interaction, when the nuclei are within 80+/-30
kpc of each other. A simple dynamical friction model for the decaying orbits
reproduces the observed distribution of projected separations, but the decay
time inferred is comparable to a Hubble time. Hence it is predicted that binary
quasars are only observable as such in the early stages of galactic collisions,
after which the quiescent super-massive black holes orbit in the merger remnant
for some time.

</DOC>
<DOC>
<DOCNO> 170067 </DOCNO>
Quantum Revivals in a Periodically Driven Gravitational Cavity


  Quantum revivals are investigated for the dynamics of an atom in a driven
gravitational cavity. It is demonstrated that the external driving field
influences the revival time significantly. Analytical expressions are presented
which are based on second order perturbation theory and semiclassical secular
theory. These analytical results explain the dependence of the revival time on
the characteristic parameters of the problem quantitatively in a simple way.
They are in excellent agreement with numerical results.

</DOC>
<DOC>
<DOCNO> 13454 </DOCNO>
The influence of the extent of excluded volume interactions on the


  The Rouse model has recently been modified to take into account the excluded
volume interactions that exist between various parts of a polymer chain by
incorporating a narrow Gaussian repulsive potential between pairs of beads on
the Rouse chain (cond-mat/0002448). The narrow Gaussian potential is
characterized by two parameters: z* - which accounts for the strength of the
interaction, and d* - which accounts for the extent of the interaction. In the
limit of d* going to zero, the narrow Gaussian potential tends to the more
commonly used delta-function repulsive potential. The influence of the
parameter d*, in the limit of infinite chain length, on equilibrium and linear
viscoelastic properties, and on universal ratios involving these properties, is
examined here. A renormalization group calculation of the end-to-end vector
suggests that the value chosen for the variable d* will not affect critical
exponents, or universal ratios. A similar trend is also observed for results
obtained with an approximate solution, which is based on the assumption that
the non-equilibrium configurational distribution function is Gaussian.

</DOC>
<DOC>
<DOCNO> 150496 </DOCNO>
Effects of Magnetic Fields on String Pair Creation


  The rate of pair production of open strings in general uniform
electromagnetic fields is calculated in various space-time dimensions. The
corrections with respect to the case of pure electric backgrounds are
displayed. In particular, a contribution in the form of a Born-Infeld action is
derived and its role in the present context emphasized

</DOC>
<DOC>
<DOCNO> 117947 </DOCNO>
Eclipse studies of the dwarf-nova Ex Draconis


  We report on high speed photometry of EX Dra in quiescence and in outburst.
The analysis of the lightcurves indicates that the outbursts do not start in
the outer disc regions. The disc expands during rise to maximum and shrinks
during decline and along the quiescent period. At the end of two outbursts the
system was seen to go through a phase of lower brightness, characterized by an
out-of-eclipse level ~15 per cent lower than the typical quiescent level and by
the fairly symmetric eclipse of a compact source at disc centre with little
evidence of a bright spot at disc rim. New eclipse timings were measured and a
revised ephemeris was derived. The residuals with respect to the linear
ephemeris are well described by a sinusoid of amplitude 1.2 minutes and period
\~4 years and are possibly related to a solar-like magnetic activity cycle in
the secondary star. Eclipse phases of the compact central source and of the
bright spot were used to derive the geometry of the binary. By constraining the
gas stream trajectory to pass through the observed position of the bright spot
we find q=0.72+/-0.06 and i= 85 +3/-2 degrees. The binary parameters were
estimated by combining the measured mass ratio with the assumption that the
secondary star obeys an empirical main sequence mass-radius relation. We find
M_1= 0.75+/-0.15 M_sun and M_2= 0.54+/-0.10 M_sun. The white dwarf at disc
centre is surrounded by an extended and variable atmosphere or boundary layer
of at least 3 times its radius and a temperature of T ~28000 K. The fluxes at
mid-eclipse yield an upper limit to the contribution of the secondary star and
lead to a lower limit photometric parallax distance of D= 290+/-80 pc. The
fluxes of the secondary star are well matched by those of a M0+/-2 main
sequence star.

</DOC>
<DOC>
<DOCNO> 84725 </DOCNO>
New Developments in the Search for the Topology of the Universe


  Multi-connected Universe models with space idenfication scales smaller than
the size of the observable universe produce topological images in the catalogs
of cosmic sources. In this review, we present the recent developments for the
search of the topology of the universe focusing on three dimensional methods.
We present the crystallographic method, we give a new lower bound on the size
of locally Euclidean multi-connected universe model of $3000 h^{-1} \hbox{Mpc}$
based on this method and a quasar catalog, we discuss its successes and
failures, and the attemps to generalise it. We finally introduce a new
statistical method based on a collecting correlated pair (CCP) technique.

</DOC>
<DOC>
<DOCNO> 150499 </DOCNO>
Interactions of Massive Integer-Spin Fields


  We review the interactions of massive fields of arbitrary integer spins with
the constant electromagnetic field and symmetrical Einstein space in the gauge
invariant framework. The problem of obtaining the gauge-invariant Lagrangians
of integer spin fields in an external field is reduced to purely algebraic
problem of finding a set of operators with certain features using the
representation of the higher-spin fields in the form of vectors in a
pseudo-Hilbert space. Such a construction is considered up to the second order
for the electromagnetic field and at linear approximation for symmetrical
Einstein space. The results obtained are valid for space-time of arbitrary
dimensionality.

</DOC>
<DOC>
<DOCNO> 9712 </DOCNO>
Elastic moduli renormalization in self interacting stretchable


  We study the effect of intersegment interactions on the effective bending and
stretching moduli of a semiflexible polymer chain with a finite stretching
modulus. For an interaction potential of a screened Debye-H\" uckel type
renormalization of the stretching modulus is derived on the same level of
approximation as the celebrated Odijk-Skolnick-Fixman result for the bending
modulus. The presence of mesoscopic intersegment interaction potentials couples
the bending and stretching moduli in a manner different from that predicted by
the macroscopic elasticity theory. We advocate a fundamental change in the
perspective regarding the dependence of elastic moduli of a flexible
polyelectrolyte on the ionic conditions: stretchability. Not only are the
persistence length as well as the stretching modulus dependent on the salt
conditions in the solution, they are fundamentally coupled via the mesoscopic
intersegment interaction potential. The theory presented here compares
favorably with recent experiments on DNA bending and stretching.

</DOC>
<DOC>
<DOCNO> 120207 </DOCNO>
The density of extremely red objects around high-z radio-loud AGN


  We present the results of a K-band imaging survey of 40 arcmin^{2} in fields
around 14 radio-loud AGN (6 radio galaxies and 8 quasars) with z>1.5. The
survey, 80% complete to K<19.2 and complemented by R-band imaging, aimed at
investigating whether extremely red objects (EROs) are present in excess around
high-z AGN, and to study the environment of z>1.5 radio galaxies and radio-loud
quasars. At $18<K<19$ the differential galaxy counts in our fields suggest a
systematic excess over the general field counts. At K<19.2, we find an excess
of galaxies with R-K>6 compared to the general field. Consistently, we also
find that the R-K colour distribution of all the galaxies in the AGN fields are
significantly redder than the colour distribution of the field galaxies. On the
other hand, the distribution of the R-K colours is undistinguishable from that
of galaxies taken from literature fields around radio-loud quasars at 1<z<2. We
discuss the main implications of our findings and we compare the possible
scenarios which could explain our results.

</DOC>
<DOC>
<DOCNO> 85306 </DOCNO>
Acceleration of the Universe as a consequence of gravitation properties


  The analysis of the data from the distant supernovae (A.Riess et al,
Astron.J. {\bf 116}, 1009, (1988)) for acceleration of the expending Universe
from the viewpoint of the gravitation equations proposed by one of the authors
(Phys.Lett. {\bf 156}, 404 (1991)) is given. It is shown that the result from
the above data that the deceleration parameter $q_{0}$ is negative is a natural
consequence of the property of the gravitation force which follows from the
above gravitation equations . It is an alternative explanation to general
relativity where a nonzero cosmological constant is used to explain the data.

</DOC>
<DOC>
<DOCNO> 12428 </DOCNO>
Multidimensional replica-exchange method for free-energy calculations


  We have developed a new simulation algorithm for free-energy calculations.
The method is a multidimensional extension of the replica-exchange method.
While pairs of replicas with different temperatures are exchanged during the
simulation in the original replica-exchange method, pairs of replicas with
different temperatures and/or different parameters of the potential energy are
exchanged in the new algorithm. This greatly enhances the sampling of the
conformational space and allows accurate calculations of free energy in a wide
temperature range from a single simulation run, using the weighted histogram
analysis method.

</DOC>
<DOC>
<DOCNO> 80644 </DOCNO>
Wave functions for Hamiltonian Lattice Gauge Theory


  We study four dimensional SU(2) lattice gauge theory in the Hamiltonian
formalism by Green's Function Monte Carlo methods. A trial ground state wave
function is introduced to improve the configuration sampling and we discuss the
interplay between its complexity and the simulation systematic errors. As a
case study, we compare the leading strong coupling approximation and an
improved 4 parameters wave function with 1X1 and 1X2 plaquette terms. Our
numerical results favors the second option.

</DOC>
<DOC>
<DOCNO> 119638 </DOCNO>
An alpha theory of time-dependent warped accretion discs


  The non-linear fluid dynamics of a warped accretion disc was investigated in
an earlier paper by developing a theory of fully non-linear bending waves in a
thin, viscous disc. That analysis is here extended to take proper account of
thermal and radiative effects by solving an energy equation that includes
viscous dissipation and radiative transport. The problem is reduced to simple
one-dimensional evolutionary equations for mass and angular momentum, expressed
in physical units and suitable for direct application. This result constitutes
a logical generalization of the alpha theory of Shakura & Sunyaev to the case
of a time-dependent warped accretion disc. The local thermal-viscous stability
of such a disc is also investigated.

</DOC>
<DOC>
<DOCNO> 12807 </DOCNO>
First order metamagnetic transition in CeFe$_2$ based pseudobinary


  We present results of dc magnetisation study showing that the low temperature
antiferromagnetic state in various CeFe$_2$-based pseudobinary alloys can be
transformed into ferromagnetic state through a magnetic field induced phase
transition. We highlight the presence of hysteresis and phase coexistence
across this metamagnetic transition and argue that the observed phase
transition is of first order in nature.

</DOC>
<DOC>
<DOCNO> 121015 </DOCNO>
ISO impact on stellar models and vice versa


  We present a detailed spectroscopic study of a sample of bright, mostly cool,
stars observed with the Short-Wavelength Spectrometer (SWS) on board the
Infrared Space Observatory (ISO), which enables the accurate determination of
the stellar parameters of the cool giants, but also serves as a critical review
of the ISO-SWS calibration.

</DOC>
<DOC>
<DOCNO> 10245 </DOCNO>
Microscopic models of traveling wave equations


  Reaction-diffusion problems are often described at a macroscopic scale by
partial derivative equations of the type of the Fisher or
Kolmogorov-Petrovsky-Piscounov equation. These equations have a continuous
family of front solutions, each of them corresponding to a different velocity
of the front. By simulating systems of size up to N=10^(16) particles at the
microscopic scale, where particles react and diffuse according to some
stochastic rules, we show that a single velocity is selected for the front.
This velocity converges logarithmically to the solution of the F-KPP equation
with minimal velocity when the number N of particles increases. A simple
calculation of the effect introduced by the cutoff due to the microscopic scale
allows one to understand the origin of the logarithmic correction.

</DOC>
<DOC>
<DOCNO> 150955 </DOCNO>
Irreducible Hamiltonian BRST symmetry for reducible first-class systems


  An irreducible Hamiltonian BRST quantization method for reducible first-class
systems is proposed. The general theory is illustrated on a two-stage reducible
model, the link with the standard reducible BRST treatment being also
emphasized.

</DOC>
<DOC>
<DOCNO> 151886 </DOCNO>
QED_2+1: the Compton effect


  The Compton effect in a two-dimensional world is compared with the same
process in ordinary three-dimensional space.

</DOC>
<DOC>
<DOCNO> 101799 </DOCNO>
Geometry and arithmetic on a quintic threefold


  The paper investigates some aspects of the geometry and the arithmetic of a
non-rigid Calabi-Yau threefold. Particular emphasis is given to the study of
its L-function L(H^3,s) and the Galois representation.

</DOC>
<DOC>
<DOCNO> 70435 </DOCNO>
Testing Left-Right Symmetric Gauge Theories at e^+e^- Colliders


  If the Standard Model is embedded in a left-right symmetric gauge theory at
the TeV scale, the pair production of light W-bosons in e^+e^- collisions,
e^+e^- -> W^+W^-, will be affected by mixings in the gauge and neutrino
sectors, and by the t-channel exchange of a heavy right-handed neutrino. The
modification of the cross section by these new effects is studied for
high--energy e^+e^- colliders.

</DOC>
<DOC>
<DOCNO> 69628 </DOCNO>
Evidence for the absence of regularization corrections to the


  The equivalence of the covariant renormalization and the partial-wave
renormaliz ation (PWR) approach is proven explicitly for the one-loop
self-energy correction (SE) of a bound electron state in the presence of
external perturbation potentials. No spurious correctio n terms to the
noncovariant PWR scheme are generated for Coulomb-type screening potentia ls
and for external magnetic fields. It is shown that in numerical calculations of
the SE with Coulombic perturbation potential spurious terms result from an
improper treatment of the unphysical high-energy contribution. A method for
performing the PWR utilizing the relativistic B-spline approach for the
construction of the Dirac spectrum in external magnetic fields is proposed.
This method is applied for calculating QED corrections to the bound-electron
$g$-factor in H-like ions. Within the level of accuracy of about 0.1% no
spurious terms are generated in numerical calculations of the SE in magnetic
fields.

</DOC>
<DOC>
<DOCNO> 13282 </DOCNO>
Topological Phases in Graphitic Cones


  The electronic structure of graphitic cones exhibits distinctive topological
features associated with the apical disclinations. Aharonov-Bohm
magnetoconductance oscillations (period Phi_0) are completely absent in rings
fabricated from cones with a single pentagonal disclination. Close to the apex,
the local density of states changes qualitatively, either developing a cusp
which drops to zero at the Fermi energy, or forming a region of nonzero density
across the Fermi energy, a local metalization of graphene.

</DOC>
<DOC>
<DOCNO> 120216 </DOCNO>
What is the Cosmic-Ray luminosity of our Galaxy?


  The total cosmic-ray luminosity of the Galaxy is an important constraint on
models of cosmic-ray generation. The diffuse high energy $\gamma$-ray and
radio-synchrotron emissions of the Milky Way are used to derive this
luminosity. The result is almost two orders of magnitude larger than the
standard estimate, based on the observed isotopic abundances of cosmic ray
nuclides. We discuss the plausible interpretation of this discrepancy and the
possible origin of such a relatively large luminosity.

</DOC>
<DOC>
<DOCNO> 14060 </DOCNO>
A Self-organising Model of Market with Single Commodity


  We have studied here the self-organising features of the dynamics of a model
market, where the agents `trade' for a single commodity with their money. The
model market consists of fixed numbers of economic agents, money supply and
commodity. We demonstrate that the model, apart from showing a self-organising
behaviour, indicates a crucial role for the money supply in the market and also
its self-organising behaviour is seen to be significantly affected when the
money supply becomes less than the optimum. We also observed that this optimal
money supply level of the market depends on the amount of `frustration' or
scarcity in the commodity market.

</DOC>
<DOC>
<DOCNO> 116566 </DOCNO>
Inversionless amplification and laser-induced transparency at the


  The effects of coherence of quantum transitions and the interference of
resonant nonlinear optical processes on the spectra of absorption,
amplification, and nonlinear-optical generation are considered. The most
favorable conditions are discussed for the inversionless amplification,
resonant refraction in the absence of absorption and for resonant enhancement
of nonlinear-optical generation at the discrete transitions and the transitions
to continuum.

</DOC>
<DOC>
<DOCNO> 67808 </DOCNO>
Azimuthal Spin Asymmetries in Semi-Inclusive Production from


  The recent measurements of azimuthal single spin asymmetries by the HERMES
collaboration at DESY may shed some light on presently unknown fragmentation
and distribution functions. We present a study of such functions and give some
estimates of weighted integrals directly related to those measurements.

</DOC>
<DOC>
<DOCNO> 117484 </DOCNO>
Correlated X-ray Spectral and Timing Behavior of the Black Hole


  We present an analysis of RXTE data of the X-ray transient XTE J1550-564. The
source went through several states, which were divided into spectrally soft and
hard states. These states showed up as distinct branches in the color-color
diagram, forming a structure with a comb-like topology; the soft state branch
forming the spine and the hard state branches forming the teeth. Variability
was strongly correlated with the position on the branches. The broad band noise
became stronger, and changed from power law like to band limited, as the
spectrum became harder. Three types of QPOs were found: 1-18 Hz and 102-284 Hz
QPOs on the hard branches, and 16-18 Hz QPOs on and near the soft branch. The
frequencies of the high and low frequency QPOs on the hard branches were
correlated with each other, and anti-correlated with spectral hardness. The
changes in QPO frequency suggest that the inner disc radius only increases by a
factor of 3-4 as the source changes from a soft to a hard state. Our results on
XTE J1550-564 strongly favor a 2-dimensional description of black hole
behavior, where the regions near the spine of the comb in the color-color
diagram can be identified with the high state, and the teeth with transitions
from the high state, via the intermediate state (which includes the very high
state) to the low state, and back. The two physical parameters underlying this
behavior vary to a large extent independently and could for example be the mass
accretion rate through the disk and the size of a Comptonizing region.

</DOC>
<DOC>
<DOCNO> 9863 </DOCNO>
Drift without flux: Brownian walker with a space dependent diffusion


  Space dependent diffusion of micrometer sized particles has been directly
observed using digital video microscopy. The particles were trapped between two
nearly parallel walls making their confinement position dependent.
Consequently, not only did we measure a diffusion coefficient which depended on
the particles' position, but also report and explain a new effect: a drift of
the particles' individual positions in the direction of the diffusion
coefficient gradient, in the absence of any external force or concentration
gradient.

</DOC>
<DOC>
<DOCNO> 120841 </DOCNO>
Cosmic Shear with the CFHT


  We present results of our cosmic shear survey in progress at the Canada-
France-Hawaii Telescope (CFHT). We analysed 1.7 sq. degrees of data, out of
which we measured a significant correlation of galaxy shape-orientation over
several arcmin scale. We present measurements of the variance of the shear
$<\gamma^2>$ and of the correlation functions $<e_r(\theta)e_r(0)>$,
$<e_t(\theta)e_t(0)>$. The signal is consistent with gravitational lensing by
large scale structures predictions. The level of residual systematics after PSF
correction is small compared to our measured signal. We outline several
evolutions of our work by using additional data covering 9 sq. degrees.

</DOC>
<DOC>
<DOCNO> 8056 </DOCNO>
Ferromagnetism below the Stoner limit in La-doped SrB_6


  Spin-polarized band calculations for LaSr_7B_{48} show a weak ferro-magnetic
state. This is despite a low density-of-states (DOS) and a low Stoner factor.
The reason for the magnetic state is found to be associated with a gain in
potential energy in addition to the exchange energy, as a spin-splitting is
imposed. An impurity like La DOS is essential for this effect. It makes a
correction to the Stoner factor, and provides an explanation of the recently
observed weak ferro-magnetism in doped hexaborides.

</DOC>
<DOC>
<DOCNO> 39973 </DOCNO>
Signatures of massive sgoldstinos at hadron colliders


  In supersymmetric extensions of the Standard Model with a very light
gravitino, the effective theory at the weak scale should contain not only the
goldstino, but also its supersymmetric partners, the sgoldstinos. In the
simplest case, the goldstino is a gauge-singlet and its superpartners are two
neutral spin-0 particles, S and P. We study possible signals of massive
sgoldstinos at hadron colliders, focusing on those that are most relevant for
the Tevatron. We show that inclusive production of sgoldstinos, followed by
their decay into two photons, can lead to observable signals or to stringent
combined bounds on the gravitino and sgoldstino masses. Sgoldstino decays into
two gluon jets may provide a useful complementary signature.

</DOC>
<DOC>
<DOCNO> 120485 </DOCNO>
H-alpha Photometry of Abell 2390


  We present the results of a search for strong H-alpha emission line galaxies
(rest frame equivalent widths greater than 50 A) in the z=0.23 cluster Abell
2390. The survey contains 1189 galaxies over 270 square arcminutes, and is 50%
complete at M_r=-17.5+5 log h. The fraction of galaxies in which H-alpha is
detected at the 2sigma level rises from 0.0 in the central regions (excluding
the cD galaxy) to 12.5+/-8% at R200. For 165 of the galaxies in our catalogue,
we compare the H-alpha equivalent widths with their [OII] equivalent widths,
from the CNOC1 spectra. The fraction of strong H-alpha emission line galaxies
is consistent with the fraction of strong [OII] emission galaxies in the CNOC1
sample: only 2+/-1% have no detectable [OII] emission and yet significant
(>2sigma) H-alpha equivalent widths. Dust obscuration, non-thermal ionization,
and aperture effects are all likely to contribute to this non-correspondence of
emission lines. We identify six spectroscopically 'secure' k+a galaxies
(W(OII)<5 A and W(Hdelta)>5 A); at least two of these show strong signs in
H-alpha of star formation in regions that are covered by the slit from which
the spectra were obtained. Thus, some fraction of galaxies classified k+a based
on spectra shortward of 6000 A are likely to be undergoing significant star
formation. These results are consistent with a 'strangulation' model for
cluster galaxy evolution, in which star formation in cluster galaxies is
gradually decreased, and is neither enhanced nor abruptly terminated by the
cluster environment.

</DOC>
<DOC>
<DOCNO> 120775 </DOCNO>
Effects of Neutrino Trapping on Thermodynamic Properties of Nuclear


  Geometrical structure of matter at subnuclear densities is investigated in
the presence of a degenerate gas of neutrinos as encountered in stellar
collapse. The crystalline phases with spherical, cylindrical and planar nuclei
as well as with spherical and cylindrical nuclear bubbles are considered by
using a compressible liquid-drop model. This model allows for uncertainties in
the lepton fraction $Y_{\rm L}$ in addition to those in the nuclear surface
tension $E_{\rm surf}$ and in the proton chemical potential in bulk neutron
matter $\mu_{\rm p}^{(0)}$. The phase diagrams obtained at zero temperature
show that only the phases with rod-like and slab-like nuclei occur at typical
values of $Y_{\rm L}$, $E_{\rm surf}$ and $\mu_{\rm p}^{(0)}$, whereas the
bubble phases, especially with spherical bubbles, are at best expected at
hypothetically low values of $Y_{\rm L}$ and/or $E_{\rm surf}$. For the
rod-like and slab-like nuclei, thermally induced displacements are calculated
from their respective elastic constants. It is found that at temperatures
appropriate to supernova cores, thermal fluctuations would destroy the layered
lattice of slab-like nuclei almost independently of the nuclear models and of
the degree of the neutrino degeneracy.

</DOC>
<DOC>
<DOCNO> 119252 </DOCNO>
Evidence for tidal interaction and a supergiant HI shell in the Local


  We present a wide-field, high spatial and velocity resolution map of the
entire extended HI distribution of the Local Group dwarf galaxy NGC 6822. The
observations were obtained with the Australia Telescope Compact Array in
mosaicing mode. The interstellar medium of NGC 6822 is shaped by the presence
of numerous H{\sc i} holes and shells, including a supergiant shell, and the
effects of tidal interaction, in the form of a tidal arm and an infalling or
interacting HI complex. The HI shell is situated outside the optical galaxy and
occupies roughly a quarter of the area of the main HI disk. It measures 2.0
times 1.4 kpc, making it one of the largest supergiant HI shells ever found.
The giant hole shows no signs of expansion and no obvious creation mechanism is
evident from our data. If star formation was the cause, an energy equivalent of
\~100 supernovae (10^53 erg) is needed to create the hole. We derive an upper
limit for the age of order 100 Myr. The presence of a possible tidal arm
indicates that NGC 6822 may recently have undergone some interaction. An HI
complex located in the north-west of the galaxy may be the interaction partner.
We argue that it is likely that these features were created about 100 Myr ago
in an event that also enhanced the star formation rate

</DOC>
<DOC>
<DOCNO> 151425 </DOCNO>
Effective String Tension and Renormalizability: String Theory in a


  We show that the one loop amplitudes of open and closed string theory in a
constant background two-form tensor field are characterized by an effective
string tension larger than the fundamental string tension, and by the
appearance of antisymmetric and symmetric noncommutativity parameters. We
derive the form of the phase functions normalizing planar and nonplanar tachyon
scattering amplitudes in this background, verifying the decoupling of the
closed string sector in the regime of infinite momentum transfer. We show that
the functional dependence of the phase functions on the antisymmetric star
product of external momenta permits interpretation as a finite wavefunction
renormalization of vertex operators in the open string sector. Using
world-sheet duality we clarify the regimes of finite and zero momentum transfer
between boundaries, demonstrating the existence of poles in the nonplanar
amplitude when the momentum transfer equals the mass of an on-shell closed
string state. Neither noncommutativity parameter has any impact on the
renormalizability of open and closed string theory in the Wilsonian sense. We
comment on the relationship to noncommutative scalar field theory and the UV-IR
correspondence.

</DOC>
<DOC>
<DOCNO> 101160 </DOCNO>
Edge Effects on Local Statistics in Lattice Dimers: A Study of the Aztec


  We compute the probability of any local pattern at an arbitrary position in a
random dimer configuration in a square grid with an Aztec-diamond boundary.

</DOC>
<DOC>
<DOCNO> 121640 </DOCNO>
Dust Formation in Primordial Type II Supernovae


  We have investigated the formation of dust in the ejecta of Type II
supernovae (SNe), mostly of primordial composition, to answer the question of
where are the first solid particles formed in the universe. However, we have
also considered non-zero progenitor's metallicity values up to Z=Zsun. The
calculations are based on standard nucleation theory and the scheme has been
first tested on the well studied case of SN1987A, yielding results that are in
agreement with the available data. We find that: i) the first dust grains are
predominantly made of silicates, amorphous carbon (AC), magnetite, and
corundum; ii) the largest grains are the AC ones, with sizes around 300 A,
whereas other grain types have smaller radii, around 10-20 A. The grain size
distribution depends somewhat on the thermodynamics of the ejecta expansion and
variations in the results by a factor ~ 2 might occur within reasonable
estimates of the relevant parameters. Also, and for the same reason, the grain
size distribution, is essentially unaffected by metallicity changes. The
predictions on the amount of dust formed are very robust: for Z=0, we find that
SNe with masses in the range (12-35) Msun produce about 0.08 Msun < M_dust <
0.3 Msun of dust/SN. The above range increases by roughly 3 times as the
metallicity is increased to solar values. We discuss the implications and the
cosmological consequences of the results.

</DOC>
<DOC>
<DOCNO> 11536 </DOCNO>
Magnetoresistance induced by low-field control of phase separation in


  The effect of low magnetic fields on the transport properties of a manganite
compound with magnetic phase separation is studied. The different behavior
obtained in samples of La0.5Ca0.5MnO3 related to the way in which the low field
is applied is consistent with a picture of changes in the metallic fraction
induced by the magnetic field in a field-cooled cycle. Using a simple model of
conduction through a binary mixture, the interrelation between
magnetoresistance, metallic fraction and percolation temperature is accounted
for. A new physical coefficient relating magnetic field and metallic fraction
emerges as the relevant parameter in the description of phase separated
manganites.

</DOC>
<DOC>
<DOCNO> 101123 </DOCNO>
Output Feedback Control of Jet Engine Stall and Surge Using Pressure


  The problem of controlling surge and stall in jet engine compressors is of
fundamental importance in preventing damage and lengthening the life of these
components. In this paper, we use the Moore-Greitzer mathematical model to
develop an output feedback controller for these two instabilities (only one of
the three states is measurable). This problem is particularly challenging since
the system is not completely observable and, hence, none of the output feedback
control techniques found in the literature can be applied to recover the
performance of a full state feedback controller. However, we show how to
successfully solve it by using a novel output feedback approach for the
stabilization of general stabilizable and incompletely observable systems.

</DOC>
<DOC>
<DOCNO> 121767 </DOCNO>
WFPC2 Observations of Massive and Compact Young Star Clusters in M31


  We present color magnitude diagrams of four blue massive and compact star
clusters in M31: G38, G44, G94, and G293. The diagrams of the four clusters
reveal a well-populated upper main sequence and various numbers of supergiants.
The U-B and B-V colors of the upper main sequence stars are used to determine
reddening estimates of the different lines of sight in the M31 disk. Reddening
values range from E(B-V) = 0.20 +/- 0.10 to 0.31 +/- 0.11. We statistically
remove field stars on the basis of completeness, magnitude and color. Isochrone
fits to the field-subtracted, reddening-corrected diagrams yield age estimates
ranging from 63 +/- 15 Myr to 160 +/- 60 Myr. Implications for the recent
evolution of the disk near NGC 206 are discussed.

</DOC>
<DOC>
<DOCNO> 99324 </DOCNO>
Irreducible degenerations of primary Kodaira surfaces


  We classify irreducible d-semistable degenerations of primary Kodaira
surfaces. As an application we construct a canonical completion for the moduli
space of primary Kodaira surfaces.

</DOC>
<DOC>
<DOCNO> 99369 </DOCNO>
A generalization of Jaynes' principle: an information-theoretic


  By considering the "kinetic-energy" term of the minimum principle for the
Schr\"{o}dinger equation as a measure of information, that minimum principle is
viewed as a statistical estimation procedure, analogous to the manner in which
Jaynes ({\it Phys. Rev.},{\bf 106}, 620, 1957) interpreted statistical
mechanics. It is shown that the entropy formula of Boltzmann and Jaynes obey a
property in common with the quantum-mechanical kinetic energy, in which both
quantities are interpreted as measures of correlation. It is shown that this
property is shared by the key terms in the minimum principles of relativistic
quantum mechanics and General Relativity. It is shown how this principle may be
extended to non-Riemannian nonEuclidean spaces, which leads to novel field
equations for the torsion.

</DOC>
<DOC>
<DOCNO> 8978 </DOCNO>
Coulomb gap in a model with finite charge transfer energy


  The Coulomb gap in a donor-acceptor model with finite charge transfer energy
$\Delta$ describing the electronic system on the dielectric side of the
metal-insulator transition is investigated by means of computer simulations on
two- and three-dimensional finite samples with a random distribution of equal
amounts of donor and acceptor sites. Rigorous relations reflecting the symmetry
of the model presented with respect to the exchange of donors and acceptors are
derived. In the immediate neighborhood of the Fermi energy $\mu$ the the
density of one-electron excitations $g(\epsilon)$ is determined solely by
finite size effects and $g(\epsilon)$ further away from $\mu$ is described by
an asymmetric power law with a non-universal exponent, depending on the
parameter $\Delta$.

</DOC>
<DOC>
<DOCNO> 117667 </DOCNO>
Pulse shape and spectrum of PSR J0218+4232 observed with BeppoSAX


  We present the results of a BeppoSAX observation of PSR J0218+4232 which, for
the first time, provides detailed information on the pulsar's temporal and
spectral emission properties in the broad band 1-10 keV. We detected X-ray
pulses with a pulsed fraction of 73 +/- 12 %. The pulse profile is
characterized by two peaks phase separated by 0.47 +/-0.05. The pulsed spectrum
is best described by a power-law of photon index 0.61 +/- 0.32 with an
unabsorbed (2-10 keV) X-ray flux of 4.1E-13 erg/cm^2/s implying a luminosity of
Lx = 1.3E32 Theta (d/5.7 kpc})^2 erg/s and an X-ray efficiency of 4.8E-4 Theta
(d/5.7 kpc})^2 where Theta is the solid angle spanned by the emission beam.

</DOC>
<DOC>
<DOCNO> 121430 </DOCNO>
Numerical study of the cosmic shear


  We study cosmic shear statistics using the ray-tracing simulation combined
with a set of large $N$-body simulations. In this contribution, we first
describe our method. Then we show some selected results especially focusing on
effects of the deflection of light rays and the lens-lens coupling which are
neglected in making the theoretical predictions of the cosmic shear statistics.

</DOC>
<DOC>
<DOCNO> 71782 </DOCNO>
The Higgs sector in the minimal 3-3-1 model with the most general


  The Higgs sector of the minimal 3 - 3 - 1 model with three triplets and one
sextet is investigated in detail under the most general lepton--number
conserving potential. The mass spectra and multiplet decompostion structure are
explicitly given in a systematic order and a transparent way allowing they to
be easily checked and used in further investigations. A previously arising
problem of inconsistent signs of f_{2} is also automatically solved.

</DOC>
<DOC>
<DOCNO> 8687 </DOCNO>
Breakdown of the Onsager reaction field theory in two dimensions


  It is shown that for the spin 1/2 anisotropic Heisenberg model the result for
the transition temperature is completely insensitive to the anisotropy within
the Onsager reaction field theory, which yields a vanishing T_c in two
dimensions, in total conflict with the expected finite T_c, increasing with
anisotropy. This establishes that the breakdown of the Onsager reaction field
theory in two dimensions is not limited to the Ising model, but actually
extends over the whole range of anisotropy. Therefore, for the isotropic case,
the results of vanishing T_c and exponential dependence of spin correlation
length should be seen as mere coincidence.

</DOC>
<DOC>
<DOCNO> 170263 </DOCNO>
Generalization of the Peres criterion for local realism through


  A bipartite spin-1/2 system having the probabilities $\frac{1+3x}{4}$ of
being in the Einstein-Podolsky-Rosen entangled state $|\Psi^-$$> \equiv
\frac{1}{\sqrt
2}(|$$\uparrow>_A|$$\downarrow>_B$$-|$$\downarrow>_A|$$\uparrow>_B)$ and
$\frac{3(1-x)}{4}$ of being orthogonal, is known to admit a local realistic
description if and only if $x<1/3$ (Peres criterion). We consider here a more
general case where the probabilities of being in the entangled states
$|\Phi^{\pm}$$> \equiv \frac{1}{\sqrt 2}(|$$\uparrow>_A|$$\uparrow>_B \pm
|$$\downarrow>_A|$$\downarrow>_B)$ and $|\Psi^{\pm}$$> \equiv \frac{1}{\sqrt
2}(|$$\uparrow>_A|$$\downarrow>_B \pm |$$\downarrow>_A|$$\uparrow>_B)$ (Bell
basis) are given respectively by $\frac{1-x}{4}$, $\frac{1-y}{4}$,
$\frac{1-z}{4}$ and $\frac{1+x+y+z}{4}$. Following Abe and Rajagopal, we use
the nonextensive entropic form $S_q \equiv \frac{1- Tr \rho^q}{q-1} (q \in
\cal{R}; $$S_1$$= -$ $Tr$ $ \rho \ln \rho)$ which has enabled a current
generalization of Boltzmann-Gibbs statistical mechanics, and determine the
entire region in the $(x,y,z)$ space where local realism is admissible. For
instance, in the vicinity of the EPR state, classical realism is possible if
and only if $x+y+z<1$, which recovers Peres' criterion when $x=y=z$. In the
vicinity of the other three states of the Bell basis, the situation is
identical. A critical-phenomenon-like scenario emerges. These results
illustrate the computational power of this new nonextensive-quantum-information
procedure.

</DOC>
<DOC>
<DOCNO> 9333 </DOCNO>
Spectroscopy of Matter Near Criticality


  We propose that the finite-frequency susceptibility of matter near a class of
zero-temperature phase transition exhibits distinctive excitonic structure
similar to meson resonances. The specific case of a Landau level undergoing a
transition to antiferromagnetism is considered as a prototype. A physical
analogy is drawn between the behavior calculated for such systems by
epsilon-expansion techniques and the behavior of 1-dimensional spin chains
calculated by exact diagonalization. It is proposed that the correct low-energy
description of such critical points is a relativistic gauge theory in
spin-fractionalized coordinates, and conversely that the application of gauge
theories to solids amounts to perturbation theory about critical points.

</DOC>
<DOC>
<DOCNO> 11807 </DOCNO>
Beauty and Distance in the Stable Marriage Problem


  The stable marriage problem has been introduced in order to describe a
complex system where individuals attempt to optimise their own satisfaction,
subject to mutually conflicting constraints. Due to the potential large
applicability of such model to describe all the situation where different
objects has to be matched pairwise, the statistical properties of this model
have been extensively studied. In this paper we present a generalization of
this model, introduced in order to take into account the presence of
correlations in the lists and the effects of distance when the player are
supposed to be represented by a position in space.

</DOC>
<DOC>
<DOCNO> 68061 </DOCNO>
A new Method for computing One-Loop Integrals


  We present a new program package for calculating one-loop Feynman integrals,
based on a new method avoiding Feynman parametrization and the contraction due
to Passarino and Veltman. The package is calculating one-, two- and three-point
functions both algebraically and numerically to all tensor cases. This program
is written as a package for Maple.

</DOC>
<DOC>
<DOCNO> 8417 </DOCNO>
BCS-type mean-field theory for t-J model in su(2|1) superalgebra


  A simple version of the Bardeen-Cooper-Schrieffer (BCS)-type mean-field
theory for the t-J model is developed. The present approach rigorously treats
the constraint of no doubly occupied states and invokes two local order
parameters to implement spontaneous breaking of the global U(1)\times U(1)
symmetry. This is achieved by identifying the Hubbard operators with generators
of the su(2|1) superalgebra in the fundamental representation and employing the
CP^{1|1} parameterization for dynamical variables. As a result, an improved
phase diagram T_c(\delta) in the paramagnetic phase is obtained.

</DOC>
<DOC>
<DOCNO> 122336 </DOCNO>
Spectra of thermally unstable slim discs


  Thermal instability driven by radiation pressure might be relevant for
intrinsically bright accreting sources. The most promising candidate where this
instability seems to be at work is one of the two known galactic superluminal
sources, GRS 1915+105 (Belloni et al. 1997). In spite of being of relevance,
this scenario has not yet been confirmed by proper time-dependent modelling.
Non-linear time-dependent calculations performed by Szuszkiewicz and Miller
(1998) show that thermally unstable discs undergo limit-cycle behaviour with
successive evacuation and refilling of the central parts of the disc. This
evolution is very similar to the one proposed by Belloni et al. (1997) in their
phenomenological model. Further investigations are needed to confirm the
thermal instability being operational in this source. First of all the spectra
emitted from the disc during its evolution should be calculated and compared
with observations. Here such spectra are computed assuming local blackbody
emission from the best studied transonic disc model.

</DOC>
<DOC>
<DOCNO> 84835 </DOCNO>
Hamiltonian structure and gauge symmetries of Poincare gauge theory


  This is a review of the constrained dynamical structure of Poincare gauge
theory which concentrates on the basic canonical and gauge properties of the
theory, including the identification of constraints, gauge symmetries and
conservation laws. As an interesting example of the general approach we discuss
the teleparallel formulation of general relativity.

</DOC>
<DOC>
<DOCNO> 121797 </DOCNO>
Beyond M: Ultracool dwarfs in the Solar Neighbourhood


  I review the optical and near-infrared spectral characteristics of the
extremely cool dwarfs grouped under the new classification of type L. These
include both very low-mass stars and brown dwarfs, and we discuss the likely
temperature range. Finally, we consider the frequency of binaries amongst very
low-mass dwarfs, and the implications for formation mechanisms.

</DOC>
<DOC>
<DOCNO> 118172 </DOCNO>
Fragmentation Instability of Molecular Clouds: Numerical Simulations


  We simulate fragmentation and gravitational collapse of cold, magnetized
molecular clouds. We explore the nonlinear development of an instability
mediated by ambipolar diffusion, in which the collapse rate is intermediate to
fast gravitational collapse and slow quasistatic collapse. Initially uniform
stable clouds fragment into elongated clumps with masses largely determined by
the cloud temperature, but substantially larger than the thermal Jeans mass.
The clumps are asymmetric, with significant rotation and vorticity, and lose
magnetic flux as they collapse. The clump shapes, intermediate collapse rates,
and infall profiles may help explain observations not easily fit by
contemporary slow or rapid collapse models.

</DOC>
<DOC>
<DOCNO> 120450 </DOCNO>
Magnetic Reconnection: Sweet-Parker Versus Petschek


  The two theories for magnetic reconnection, one of Sweet and Parker, and the
other of Petschek, are reconciled by exhibiting an extra condition in that of
Petschek which reduces his theory to that of Sweet and Parker, provided that
the resistivity is constant in space. On the other hand, if the resistivity is
enhanced by instabilities, then the reconnection rate of both theories is
increased substantially, but Petschek's rate can be faster. A different formula
from the usual one is presented for enhanced Petschek reconnection.

</DOC>
<DOC>
<DOCNO> 117534 </DOCNO>
A New Model for the Spiral Structure of the Galaxy. Superposition of


  We investigate the possibility of describing the spiral pattern of the Milky
Way in terms of a model of superposition 2- and 4-armed wave harmonics (the
simplest description, besides pure modes). Two complementary methods are used:
a study of stellar kinematics, and direct tracing of positions of spiral arms.
In the first method, the parameters of the galactic rotation curve and the free
parameters of the spiral density waves were obtained from Cepheid kinematics,
under different assumptions. To turn visible the structure corresponding to
these models, we computed the evolution of an ensemble of N-particles,
simulating the ISM clouds, in the perturbed galactic gravitational field. In
the second method, we present a new analysis of the longitude-velocity (l-v)
diagram of the sample of galactic HII regions, converting positions of spiral
arms in the galactic plane into locii of these arms in the l-v diagram. Both
methods indicate that the ``self-sustained'' model, in which the 2-armed and
4-armed mode have different pitch angles (6 arcdeg and 12 arcdeg, respectively)
is a good description of the disk structure. An important conclusion is that
the Sun happens to be practically at the corotation circle. As an additional
result of our study, we propose an independent test for localization of the
corotation circle in a spiral galaxy: a gap in the radial distribution of
interstellar gas has to be observed in the corotation region.

</DOC>
<DOC>
<DOCNO> 120135 </DOCNO>
Spectroscopy of Blue Stragglers and Turnoff Stars in M67 (NGC 2682)


  We have analyzed high-resolution spectra of relatively cool blue stragglers
and main sequence turnoff stars in the old open cluster M67 (NGC 2682). We
attempt to identify blue stragglers whose spectra are least contaminated by
binary effects (contamination by a binary companion or absorption by
circumstellar material). These ``best'' stragglers have metallicities ([Fe/H] =
-0.05) and abundance ratios of the blue stragglers are not significantly
different from those of the turnoff stars. Based on arguments from
hydrodynamical models of stellar collisions, we assert that the current upper
limits for the lithium abundances of all blue stragglers observed in M67 (by us
and others) are consistent with no mixing during the formation process,
assuming pre-main sequence and main sequence depletion patterns observed for
M67 main sequence stars. We discuss composition signatures that could more
definitively distinguish between blue straggler formation mechanisms in open
cluster stars.
  We confirm the spectroscopic detection of a binary companion to the straggler
S 1082. From our spectra, we measure a projected rotational speed of 90+/-20
km/sec for the secondary, and find that its radial velocity varies with a
peak-to-peak amplitude of ~ 25 km/sec. Because the radial velocities do not
vary with a period corresponding to the partial eclipses in the system, we
believe this system is currently undergoing mass transfer. In addition we
present evidence that S 984 is a true blue straggler (and not an unresolved
pair). If this can be proven, our detection of lithium may indicate a
collisional origin.

</DOC>
<DOC>
<DOCNO> 117501 </DOCNO>
Simulating Supernovae Remnants in Gas Clouds


  The Hydra $N$-body hydrodynamics code has been modified to model, from the
end of the Sedov phase, the effects of supernovae on the surrounding medium.
The motivation is to investigate the feedback of energy into the
interstellar/intergalactic medium. We compare our results for supernova
remnants (SNRs) in a uniform medium to previous detailed work on the late
evolution of SNRs. The code is found to reproduce the bulk characteristics of
SNRs well. Results on the effects of a single central SNR on Plummer clouds are
presented. The feedback of kinetic energy and the percentage mass loss can be
parameterised in terms of the cloud mass and characteristic radius in a simple
way. The kinetic energy fraction returned to the ISM from a SNR is $<3$ per
cent. The removal of gas from the cold, dense phase and the addition of energy
due to the lowering of the potential energy of a cloud is at least as
significant, if not much more so, than the kinetic energy leaving a cloud.

</DOC>
<DOC>
<DOCNO> 13644 </DOCNO>
Option pricing and perfect hedging on correlated stocks


  We develop a theory for option pricing with perfect hedging in an inefficient
market model where the underlying price variations are autocorrelated over a
time tau. This is accomplished by assuming that the underlying noise in the
system is derived by an Ornstein-Uhlenbeck, rather than from a Wiener process.
With a modified portfolio consisting in calls, secondary calls and bonds we
achieve a riskless strategy which results in a closed expression for the
European call price which is always lower than Black-Scholes price. We also
obtain a partial differential equation for the option price and study the
sensitivity to several parameters and the risk of the dynamics of the call
price.

</DOC>
<DOC>
<DOCNO> 68102 </DOCNO>
Nuclear Enhanced Higher-Twist Effects in the Drell-Yan Process


  We calculate the Drell-Yan cross section, resolving the full kinematics of
the lepton pair, at high transverse momentum for hadron nucleus collisions. We
use the general framework of Luo, Qiu and Sterman to calculate double
scattering contributions that are of twist-4 and demonstrate their nuclear
enhancement. By comparing single and double scattering at RHIC energies we find
that double scattering gives contributions of comparable size. We also show
that the angular dependence of the Drell-Yan pair discriminates between the
various double scattering contributions.

</DOC>
<DOC>
<DOCNO> 178966 </DOCNO>
A Possible Boson Realization of Generalized Lipkin Model for


  On the basis of the formalism proposed by three of the present authors (A.K.,
J.P.and M.Y.), generalized Lipkin model consisting of (M+1) single-particle
levels is investigated. This model is essentially a kind of the
su(M+1)-algebraic model and, in contrast to the conventional treatment, the
case, where fermions are partially occupied in each level, is discussed. The
scheme for obtaining the orthogonal set for the irreducible representation is
presented.

</DOC>
<DOC>
<DOCNO> 9431 </DOCNO>
Twin wall of cubic-tetragonal ferroelastics


  We derive solutions for the twin wall linking two tetragonal variants of the
cubic-tetragonal ferroelastic transformation, including for the first time the
dilatational and shear energies and strains. Our solutions satisfy the
compatibility relations exactly and are obtained at all temperatures. They
require four non-vanishing strains except at the Barsch-Krumhansl temperature
TBK (where only the two deviatoric strains are needed). Between the critical
temperature and TBK, material in the wall region is dilated, while below TBK it
is compressed. In agreement with experiment and more general theory, the twin
wall lies in a cubic 110-type plane. We obtain the wall energy numerically as a
function of temperature and we derive a simple estimate which agrees well with
these values.

</DOC>
<DOC>
<DOCNO> 70995 </DOCNO>
Brane Universes, AdS/CFT, Hamiltonian Formalism and the Renormalization


  The AdS/CFT correspondence is developed from classical solutions on AdS_5
with two boundaries. The corresponding limits and the reduction of degrees of
freedom are discussed, as well as the required renormalization on the field
theory side. The Hamiltonian first-order approach towards the solution of
coupled gravitational/matter equations of motion is introduced, and the RG
interpretation is exposed. Finally we discuss a recent approach towards a
naturally vanishing cosmological constant which is based on the AdS/RG
correspondence.

</DOC>
<DOC>
<DOCNO> 12613 </DOCNO>
A central role for the exchange-correlation hole in the 2D


  The 2D metal-insulator transition can be induced either by decreasing the
carrier density or by increasing the spin polarization by applying a magnetic
field parallel to the plane. Using experimental results for the shift in
critical carrier density in an applied field, we show that the two-electron
pair correlation function at short distance ($k_Fr\alt2$) has a universal form
along the transition line in the magnetic field-carrier density plane. This
result provides direct evidence of the central role of Coulomb repulsion and
the exchange-correlation hole in driving the metal-insulator transition.

</DOC>
<DOC>
<DOCNO> 102877 </DOCNO>
Lefschetz fibrations on compact Stein surfaces


  The existence of a positive allowable Lefschetz fibration on a compact Stein
surface with boundary was established by Loi and Piergallini by using branched
covering techniques. Here we give an alternative simple proof of this fact and
construct explicitly the vanishing cycles of the Lefschetz fibration, obtaining
a direct identification of the set of compact Stein manifolds with positive
allowable Lefschetz fibrations over a 2-disk. In the process we associate to
every compact Stein manifold infinitely many nonequivalent such Lefschetz
fibrations.

</DOC>
<DOC>
<DOCNO> 121956 </DOCNO>
First XMM-Newton observations of a Cataclysmic Variable I: Timing


  We present XMM-Newton observations of the eclipsing, disc accreting,
cataclysmic variable OY Car which were obtained as part of the performance
verification phase of the mission. The star was observed 4 days after an
outburst and then again 5 weeks later when it was in a quiescent state. There
is a quasi-stable modulation of the X-rays at ~2240 sec, which is most
prominent at the lowest energies. We speculate that this may be related to the
spin period of the white dwarf. The duration of the eclipse ingress and egress
in X-rays is 20--30 sec. This indicates that the bulk of the X-ray emission
originates from the boundary layer which has a negligible height above the
surface of the white dwarf. The eclipse profile implies a white dwarf of mass
M_{1}=0.9-1.1Msun and a secondary star of M_{2}=0.08-0.11Msun.

</DOC>
<DOC>
<DOCNO> 118876 </DOCNO>
Studies of binary star cluster candidates in the bar of the LMC. II


  Binary clusters account for more than 10 % of the cluster population in the
Magellanic Clouds. Statistically fewer than 50 % of the found pairs are
expected to be chance superpositions. We estimated the cluster encounter rate
and suggest that tidal capture is an unlikely formation scenario for the
formation of binary clusters. Thus, most true binary clusters can be expected
to have formed together. Here we present a study of three binary cluster
candidates which are located in the bar of the LMC. NGC 1971 & NGC 1972 are
situated in the association LH 59 in the eastern part of the bar. A third star
cluster, NGC 1969, is close enough to this pair that all three objects may
constitute a triple system. We present the first age determination that is
based on CMDs for these star clusters. Our findings suggest that all three
clusters are young (40-70 Myr) and may have been formed in the same GMC. It
cannot clearly decided whether the clusters are physically interacting or not.
NGC 1894 & SL 341 are located at the south-western rim of the LMC bar. This
pair is studied in detail for the first time: The isopleths of both clusters
reveal an elliptical shape. Whether this might be interpreted as a sign of
interaction or is a peculiarity which is shared with a large amount of LMC star
clusters which show higher ellipticities than their counterparts in the Milky
Way remains unclear. From our age determination we find that both clusters are
coeval with an age of 55+/-5 Myr. This makes a formation from the same GMC a
likely scenario. SL 385 & SL 387 are a close pair in the western part of the
LMC bar. We derived ages of 170+/-30 Myr for SL 385 and >=250 Myr for SL 387.
The large age difference makes it unlikely that these two clusters formed in
the same GMC.

</DOC>
<DOC>
<DOCNO> 71351 </DOCNO>
Bounds On The Sum Of A Divergent Series


  Given a truncated perturbation expansion of a physical quantity, one can,
under certain circumstances, obtain lower or upper bounds (or both) to the sum
of the full perturbation series by using the Borel transform and a variational
conformal map. The method is illustrated by applying it to various mathematical
toy-models for which exact results are known. One of these models is used to
exemplify how non-perturbative contributions supplement the sum of a
Borel-nonsummable series to give the final exact and unambiguous result.
Finally, the method is applied to some physical problems. In particular, some
speculations are made on the phase of quantum electrodynamics at super-high
temperatures from a study of its perturbative free-energy density.

</DOC>
<DOC>
<DOCNO> 150910 </DOCNO>
Thompson's Method applied to Quantum Electrodynamics (QED)


  In this work we apply Thompson's method (of the dimensions) to study the
quantum electrodynamics (QED). This method can be considered as a simple and
alternative way to the renormalisation group (R.G) approach and when applied to
QED lagrangian is able to obtain the running coupling constant behavior $\alpha
(\mu)$, namely the dependence of $\alpha$ on the energy scale. We also obtain
the dependence of the mass on the energy scale. The calculations are evaluated
just at $d_c=4$, where $d_c$ is the upper critical dimension of the problem, so
that we obtain logarithmic behavior both for the coupling $\alpha$ and the mass
$m$ on the energy scale $\mu$.

</DOC>
<DOC>
<DOCNO> 70821 </DOCNO>
Testing A (Stringy) Model of Quantum Gravity


  I discuss a specific model of space-time foam, inspired by the modern
non-perturbative approach to string theory (D-branes). The model views our
world as a three brane, intersecting with D-particles that represent stringy
quantum gravity effects, which can be real or virtual. In this picture, matter
is represented generically by (closed or open) strings on the D3 brane
propagating in such a background. Scattering of the (matter) strings off the
D-particles causes recoil of the latter, which in turn results in a distortion
of the surrounding space-time fluid and the formation of (microscopic, i.e.
Planckian size) horizons around the defects. As a mean-field result, the
dispersion relation of the various particle excitations is modified, leading to
non-trivial optical properties of the space time, for instance a non-trivial
refractive index for the case of photons or other massless probes. Such models
make falsifiable predictions, that may be tested experimentally in the
foreseeable future. I describe a few such tests, ranging from observations of
light from distant gamma-ray-bursters and ultra high energy cosmic rays, to
tests using gravity-wave interferometric devices and terrestrial particle
physics experients involving, for instance, neutral kaons.

</DOC>
<DOC>
<DOCNO> 10120 </DOCNO>
Multi-plateau magnetization curves of one-dimensional Heisenberg


  Ground-state magnetization curves of ferrimagnetic Heisenberg chains of
alternating spins $S$ and $s$ are numerically investigated. Calculating several
cases of $(S,s)$, we conclude that the spin-$(S,s)$ chain generally exhibits
$2s$ magnetization plateaux even at the most symmetric point. In the double- or
more-plateau structure, the initial plateau is generated on a classical basis,
whereas the higher ones are based on a quantum mechanism.

</DOC>
<DOC>
<DOCNO> 69878 </DOCNO>
Physics of High-Mass Dimuon Production at the 50-GeV Proton Synchrotron


  We discuss the physics interest and the experimental feasibility for
detecting high-mass dimuon pairs using the planned 50-GeV Proton Synchrotron
(PS) at the KEK/JHF and JAERI/NSP joint accelerator project. The Drell-Yan
measurement of $p+d$ versus $p+p$ at 50 GeV will provide unique information on
the flavor asymmetry of proton's up and down sea-quark distributions in the
large-$x$ region. A study of the nuclear dependences of Drell-Yan cross
sections can reveal the modification of antiquark distributions in nuclei.
Furthermore, the effect of energy loss for fast partons traversing nuclear
medium could also be sensitively measured. If polarized proton beam becomes
available at the 50-GeV PS, unique information on the sea-quark polarization
could be obtained. Study of heavy quarkonium production at the 50-GeV PS can
set important constraints on the mechanism of vector meson productions. Using a
prototype dimuon spectrometer, we have simulated the sensitivities for a
variety of measurements.

</DOC>
<DOC>
<DOCNO> 102351 </DOCNO>
Solitons and Almost-Intertwining Matrices


  We define the set of almost-intertwining matrices to be all triples(X,Y,Z) of
n x n matrices for which XZ=YX+T for some rank one matrix T. A surprisingly
simple formula is given for tau-functions of the KP hierarchy in terms of such
triples. The tau-functions produced in this way include the soliton and
vanishing rational solutions. The induced dynamics of the eigenvalues of the
matrix X are considered, leading in special cases to the Ruijsenaars-Schneider
particle system.

</DOC>
<DOC>
<DOCNO> 71924 </DOCNO>
On Contributions of Two-Particle Correlation Functions to the


  The factorial moments (FM) of the multiplicity distributions in one- and
two-dimensions are studied in Pb+Pb collisions at 158 AGeV. Obvious
intermittency slopes are observed in the relation between FM and the partition
number M. The Bose-Einstein correlations (BEC) are investigated in the
emulsion data sample. The influences of the two-particle correlation functions
(TPCF) on the scaling behavior of FM are also investigated. The dependence of
TPCF on the invariant relative momentum Q as well as on the pseudo-rapidity
$\delta\eta$ are calculated. It is found that TPCF fulfill the requirements of
a power-law scaling comparable with the scaling rule of FM. The expected
contributions of TPCD to FM are quantitatively estimated.

</DOC>
<DOC>
<DOCNO> 83063 </DOCNO>
Agents of Choice: Tools that Facilitate Notice and Choice about Web Site


  A variety of tools have been introduced recently that are designed to help
people protect their privacy on the Internet. These tools perform many
different functions in-cluding encrypting and/or anonymizing communications,
preventing the use of persistent identifiers such as cookies, automatically
fetching and analyzing web site privacy policies, and displaying
privacy-related information to users. This paper discusses the set of privacy
tools that aim specifically at facilitating notice and choice about Web site
data practices. While these tools may also have components that perform other
functions such as encryption, or they may be able to work in conjunction with
other privacy tools, the primary pur-pose of these tools is to help make users
aware of web site privacy practices and to make it easier for users to make
informed choices about when to provide data to web sites. Examples of such
tools include the Platform for Privacy Preferences (P3P) and various
infomediary services.

</DOC>
<DOC>
<DOCNO> 71098 </DOCNO>
Multiplicity of different hadrons in e+e-, pp, and AA collisions


  Employing the recently developed neXus model, we compare the yields of
different hadrons in ultra-relativistic collisions: electron-positron
annihilation at 91 GeV, proton-proton scattering at 17 GeV and nucleus-nucleus
collisions at 17 GeV (SPS) and 200 GeV (RHIC). Plotting the yields as a
function of the hadron masses, we find very surprising results: we observe that
the spectra are practically identical for e+e- at 91 GeV and central
nucleus-nucleus reactions at SPS and RHIC energies, whereas the spectrum for
proton-proton scattering is somewhat steeper. All have the form one expects if
the particles were emitted by a canonical system which is characterized by a
temperature and chemical potentials. These identical forms have, however,
different origins: in e+e- and pp the exponential shape it is due to the
statistical behavior of string fragmentation, which has absolutely nothing to
do with thermalization, in AA it is caused by phase space. The fact that e+e-
and nuclear results agree is pure coincidence. Surprisingly the results for pp
and e+e- differ, although here the production mechanism is identical. In pp
collisions we see directly that the string energy is very limited and hence the
high mass baryons are suppressed. We conclude that it is practically impossible
to draw conclusions from hadronic yields about the reaction mechanism.

</DOC>
<DOC>
<DOCNO> 71683 </DOCNO>
Comment on "Complete One-Loop Analysis of the Nucleon's Spin


  We comment on the paper of Gellas et al, nucl-th/0002027, in which heavy
baryon chiral perturbation theory results for the spin polarisabilities of the
nucleon are given. That paper uses a definition which is different from the one
used in papers by us, hep-ph/9908526, hep-ph/9909442 and hep-ph/0002133. In
this comment we show that it is the latter definition, and not that of Gellas
et al, that should be compared with the values of the polarisabilities
extracted from dispersion relation analyses.

</DOC>
<DOC>
<DOCNO> 169648 </DOCNO>
The Role of the Environment in Molecular Systems


  The work is devoted to the investigation of the influence of a heat bath on
the physical processes in a quantum system. We use the density matrix theory as
one of the most powerfool tool for investigation of quantum relaxation. In the
beginning of the work (chapter 2) we mention and recall the most important
steps of derivation of the equation of motion for the reduced density matrix
(master equation) for an arbitrary quantum system in diabatic representation
interacting with the environment modeled by a set of independent harmonic
oscillators. Chapter 3 deals with the question of the border between classical
and quantum effects and reports on a study of the environmental influence on
the time evolution of a coherent state or the superposition of two coherent
states of a harmonic oscillator as a simple system displaying the peculiarities
of the transition from quantum to classical regime. Chapters 4 and 5 concern
the electron transfer (ET) problem, namely the mathematical description of the
ET in molecular zinc-porphyrin-quinone complexes modeling artificial
photosynthesis (chapter 4) and photoinduced processes in the porphyrin triad
(chapter 5). Each chapter starts with an introduction and ends with a brief
summary. The main achievements of the present work are summarized in the
Conclusions.

</DOC>
<DOC>
<DOCNO> 122436 </DOCNO>
Cosmological thermal decoupling and primordial molecules


  Primordial chemistry began, at the recombination epoch, when the adiabatic
expansion caused the temperature of the radiation to fall below 4000K. The
chemistry of the early Universe involves the elements hydrogen, its isotope
deuterium, helium with its isotopic forms and lithium. In this contribution I
will discuss the influence of the primordial molecules on the cosmological
decoupling. In the framework of the gravitational instability theory, each
protostructure started as a tiny local overdensity. As long as these
inhomogeneities are small, their evolution can be studied by the classical
linear perturbation theory. Once the deviations become large, the linear theory
is no more valid. we present the role played by these molecules on the
transition between the linear regime and the non-linear regime, and show that
the molecules can lead to a thermal change at the turn-around point between
these two regimes.

</DOC>
<DOC>
<DOCNO> 170172 </DOCNO>
Interaction of the quantized electromagnetic field with atoms in the


  A general theory of the interaction of the quantized electromagnetic field
with atoms in the presence of dispersing and absorbing dielectric bodies of
given Kramers--Kronig consistent permittivities is developed. It is based on a
source-quantity representation of the electromagnetic field, in which the
electromagnetic-field operators are expressed in terms of a continuous set of
fundamental bosonic fields via the Green tensor of the classical problem.
Introducing scalar and vector potentials, the formalism is extended in order to
include in the theory the interaction of the quantized electromagnetic field
with additional atoms. Both the minimal-coupling scheme and the
multipolar-coupling scheme are considered. The theory replaces the standard
concept of mode decomposition which fails for complex permittivities. It
enables us to treat the effects of dispersion and absorption in a consistent
way and to give a unified approach to the atom-field interaction, without any
restriction to a particular interaction regime in a particular frequency range.
All relevant information about the dielectric bodies such as form and intrinsic
dispersion and absorption is contained in the Green tensor. The application of
the theory to the spontaneous decay of an excited atom in the presence of
dispersing and absorbing bodies is addressed.

</DOC>
<DOC>
<DOCNO> 151095 </DOCNO>
Bogolubov's Recursion and Integrability of Effective Actions


  The Hopf algebra of Feynman diagrams, analyzed by A.Connes and D.Kreimer, is
considered from the perspective of the theory of effective actions and
generalized $\tau$-functions, which describes the action of diffeomorphism and
shift groups in the moduli space of coupling constants. These considerations
provide additional evidence of the hidden group (integrable) structure behind
the standard formalism of quantum field theory.

</DOC>
<DOC>
<DOCNO> 119096 </DOCNO>
On the oxygen abundance determination in HII regions: the problem of the


  The problem of the line intensities -- oxygen abundance calibration has been
considered. We confirm the idea of McGaugh (1991) that the strong oxygen lines
([OII] 3727, 3729 and [OIII] 4959, 5007) contain the necessary information for
determination of accurate abundances in low-metallicity (and may be also in
high-metallicity) HII regions. It has been found that the excitation parameters
p3 or p2 (which are defined here as contributions of the radiation in [OIII]
4959, 5007 lines and in [OII] 3727, 3729 lines to the "total" oxygen radiation
respectively) allow to take into account the variations in R23 values among HII
regions with a given oxygen abundance. Based on this fact a new way of the
oxygen abundance determination in HII regions has been constructed and
corresponding relations between line intensities and the oxygen abundance have
been derived empirically using the available oxygen abundances determined via
measurement of temperature-sensitive line ratios.
   In parallel a new R23 calibration has been derived on the base of recent
data and compared to previous calibrations. For oxygen-rich HII regions the
present R23 calibration is close to that of Edmunds and Pagel (1984): their
calibration has the same slope but is shifted towards higher oxygen abundances
by around 0.07 dex as compared to the present calibration.

</DOC>
<DOC>
<DOCNO> 120544 </DOCNO>
Hydrogen Lyman-alpha Absorption Predictions by Boltzmann Models of the


  We use self-consistent kinetic/hydrodynamic models of the heliosphere to
predict H I Lyman-alpha absorption profiles for various lines of sight through
the heliosphere. These results are compared with Lyman-alpha absorption lines
of six nearby stars observed by the Hubble Space Telescope. The directions of
these lines of sight range from nearly upwind (36 Oph) to nearly downwind
(Epsilon Eri). Only three of the Lyman-alpha spectra (36 Oph, Alpha Cen, and
Sirius) actually show evidence for the presence of heliospheric absorption,
which is blended with the ubiquitous interstellar absorption, but the other
three spectra still provide useful upper limits for the amount of heliospheric
absorption for those lines of sight. Most of our models use a Boltzmann
particle code for the neutrals, allowing us to estimate neutral velocity
distributions throughout the heliosphere, from which we compute model
Lyman-alpha absorption profiles. In comparing these models with the data, we
find they predict too much absorption in sidewind and downwind directions,
especially when higher Mach numbers are assumed for the interstellar wind.
Models created assuming different values of the interstellar temperature and
proton density fail to improve the agreement. Somewhat surprisingly, a model
that uses a multi-fluid treatment of the neutrals rather than the Boltzmann
particle code is more consistent with the data, and we speculate as to why this
may be the case.

</DOC>
<DOC>
<DOCNO> 40345 </DOCNO>
Centrality dependence of K+ produced in Pb+Pb collisions at 158 GeV per


  The NA52 collaboration searches for a discontinuous behaviour of charged
kaons produced in Pb+Pb collisions at 158 A GeV as a function of the impact
parameter, which could reveal a hadron to quark-gluon plasma (QGP) phase
transition. The K+ yield is found to grow proportional to the number of
participating ('wounded') nucleons N, above N=100. Previous NA52 data agree
with the above finding and show a discontinuous behaviour in the kaon
centrality dependence near N=100, marking the onset of strangeness enhancement
-over e.g. p+A data at the same \sqrt{s}- in a chemically equilibrated phase.

</DOC>
<DOC>
<DOCNO> 71672 </DOCNO>
Decays of b hadrons and a possible new four-quark interaction


  A possibility is considered of explaining the low experimental value of the
ratio of the lifetimes tau(Lambda_b)/tau(B_d) by a new `centiweak' four-quark
interaction, i.e with a strength on the order of 10^{-2}G_F. It is noted that
the considered interaction can also improve agreement with the data on low
semileptonic branching ratio B_{sl}(B) in B meson decays with a simultaneous
slight decrease in the prediction for the average charm yield in those decays.
The proposed new interaction modifies within the present experimental limits
the predictions for differences of lifetimes among B mesons, and can thus be
probed by more precise data on these differences. A sample model is briefly
discussed, where the new interaction arises through a weak SU(2) singlet scalar
field with quantum numbers of a diquark.

</DOC>
<DOC>
<DOCNO> 101267 </DOCNO>
Generalized Integer Partitions, Tilings of Zonotopes and Lattices


  In this paper, we study two kinds of combinatorial objects, generalized
integer partitions and tilings of two dimensional zonotopes, using dynamical
systems and order theory. We show that the sets of partitions ordered with a
simple dynamics, have the distributive lattice structure. Likewise, we show
that the set of tilings of zonotopes, ordered with a simple and classical
dynamics, is the disjoint union of distributive lattices which we describe. We
also discuss the special case of linear integer partitions, for which other
dynamical systems exist. These results give a better understanding of the
behaviour of tilings of zonotopes with flips and dynamical systems involving
partitions.

</DOC>
<DOC>
<DOCNO> 178469 </DOCNO>
The BCS theory of q-deformed nucleon pairs - qBCS


  We construct a coherent state of q-deformed zero coupled nucleon pairs
distributed in several single-particle orbits. Using a variational approach,
the set of equations of qBCS theory, to be solved self consistently for
occupation probabilities, gap parameter Delta, and the chemical potential
lambda, is obtained. Results for valence nucleons in nuclear degenerate sdg
major shell show that the strongly coupled zero angular momentum nucleon pairs
can be substituted by weakly coupled q-deformed zero angular momentum nucleon
pairs. A study of Sn isotopes reveals a well defined universe of (G, q) values,
for which qBCS converges. While the qBCS and BCS show similar results for Gap
parameter Delta in Sn isotopes, the ground state energies are lower in qBCS.
The pairing correlations in N nucleon system, increase with increasing q (for q
real).

</DOC>
<DOC>
<DOCNO> 70904 </DOCNO>
Gravitational Experiment Below 1 Millimeter and Comment on Shielded


  We present the status of an experimental test for gravitational strength
forces below 1 mm. Our experiment uses small 1 kilohertz oscillators as test
masses, with a stiff counducting shield between them to suppress backgrounds.
At the present sensitivity of approximately 1000 times gravitational strength,
we see no evidence for new forces with interaction ranges between 75 microns
and 1 mm. While the Casimir background is not expected to be significant at
this range, an extension of the shielding technique we employ may be useful for
reducing this background in experiments below a few microns. We describe a
possible implementation.

</DOC>
<DOC>
<DOCNO> 13881 </DOCNO>
Phase-coherence transition in granular superconductors with $\pi$


  We study the three-dimensional XY-spin glass as a model for the resistive
behavior of granular superconductors containing a random distribution of $\pi$
junctions, as in high-$T_c$ superconducting materials with d-wave symmetry. The
$\pi$ junctions leads to quenched in circulating currents (chiralities) and to
a chiral-glass state at low temperatures, even in the absence of an external
magnetic field. Dynamical simulations in the phase representation are used to
determine the nonlinear current-voltage characteristics as a function of
temperature. Based on dynamic scaling analysis, we find a phase-coherence
transition at finite temperature below which the linear resistivity should
vanish and determine the corresponding critical exponents. The results suggest
that the phase and chiralities may order simultaneously for decreasing
temperatures into a superconducting chiral-glass state.

</DOC>
<DOC>
<DOCNO> 68064 </DOCNO>
Reconstructing the Chargino System at $e^+e^-$ Linear Colliders


  In most supersymmetric theories charginos, $\tilde{\chi}^\pm_{1,2}$, belong
to the class of the lightest supersymmetric particles. The chargino system can
be reconstructed completely in $e^+e^-$ collider experiments:
$e^+e^-\to\tilde{\chi}_i^+ \tilde{\chi}_j^- [i,j=1,2]$. By measuring the total
cross sections and the asymmetries with polarized beams, the chargino masses
and the gaugino-higgsino mixing angles of these states can be determined
accurately. If only the lightest charginos $\tilde{\chi}_1^\pm$ are
kinematically accessible in a first phase of the machine, transverse beam
polarization or the measurement of chargino polarization in the final state is
needed to determine the mixing angles. From these observables the fundamental
SUSY parameters can be derived: the SU(2) gaugino mass $M_2$, the modulus and
the cosine of the CP-violating phase of the higgsino mass parameter $\mu$, and
$\tan\beta = v_2/v_1$, the ratio of the vacuum expectation values of the two
neutral Higgs doublet fields. The remaining two-fold ambiguity of the phase can
be resolved by measuring the normal polarization of the charginos. Sum rules of
the cross sections can be exploited to investigate the closure of the
two-chargino system.

</DOC>
<DOC>
<DOCNO> 122108 </DOCNO>
BVRI Surface Photometry of (S+S) Binary Galaxies


  We report the first results of our multicolour broad-band BVRI photometry for
a statistically well defined sample of interacting pairs, drawn from the
Catalogue of Isolated Pairs of Galaxies in the Northern Hemisphere Karachentsev
(1972). At present, the details of photometric structure of disk-disk (S+S)
galaxies are just beginning to be studied because of their intrinsic
difficulties. We take advantage of the statistical properties of this well
defined sample of interacting galaxies to try to isolate the main structural
components of galaxies. Due to their environmental simplicity (compared to
groups and clusters), the sample provides an unique opportunity to peform a
photometric study of galaxies and their structural components in a
non-equilibrium configuration. In this contribution, the first results of a
deep multicolour (BVRI) photometric study of a sample of 45 (S+S) isolated
pairs of galaxies is presented. Our attention is focused on the morphology and
the global photometric properties (integrated magnitudes, colours and mean
surface brightness profiles).

</DOC>
<DOC>
<DOCNO> 102905 </DOCNO>
Koszul duality and equivalences of categories


  Let A and A! be dual Koszul algebras and Kom(A) and Kom(A!) the categories of
complexes of graded left A and A!-modules. In Koszul duality one studies a
certain pair of adjoint functors F_A and G_A! between these categories. We
establish that this adjunction is basically a tensor-Hom adjunction, thereby
connecting Koszul duality with tilting theory. We extend results of Beilinson,
Ginzburg and Soergel and show that there are certain triangulated quotient
categories D^R(A) of Kom(A) and D^L(A!) of Kom(A!) such that the functors F_A
and G_A! descend to give an equivalence of triangulated categories. Also, under
certain conditions on A, the category D^R(A) is equivalent to the homotopy
category of all unbounded complexes of certain injective A-modules, thereby
making it an excellent category for doing homological algeba for left exact
functors. Analogous results hold also for D^L(A!).
  We also make further developments motivated be applications in the paper
math.AG/0012263. This is concerned with the BGG-correspondence between coherent
sheaves on a projective space P(V) and complexes of free graded modules over
the exterior algebra on V^*.

</DOC>
<DOC>
<DOCNO> 69419 </DOCNO>
N*, Lambda*, Sigma* and Xi* Resonances from J/Psi and Psi' Decays


  Vector charmonium states $J/\Psi$ and $\Psi'$ are copiously produced by
$e^+e^-$ annihilations at the Beijing Electron Positron Collider (BEPC). Their
decays provide an excellent place for studying excited nucleons and hyperons --
$N^*$, $\Lambda^*$, $\Sigma^*$ and $\Xi^*$ resonances. The systematic study of
these excited nucleons and hyperons can provide us with critical insights into
the internal quark structure of baryons.

</DOC>
<DOC>
<DOCNO> 101629 </DOCNO>
Equations, States, and Lattices of Infinite-Dimensional Hilbert Spaces


  We provide several new results on quantum state space, on lattice of
subspaces of an infinite dimensional Hilbert space, and on infinite dimensional
Hilbert space equations as well as on connections between them. In particular
we obtain an n-variable generalized orthoarguesian equation which holds in any
infinite dimensional Hilbert space. Then we strengthen Godowski's result by
showing that in an ortholattice on which strong states are defined Godowski's
equations as well as the orthomodularity hold. We also prove that all 6- and
4-variable orthoarguesian equations presented in the literature can be reduced
to new 4- and 3-variable ones, respectively and that Mayet's examples follow
from Godowski's equations. To make a breakthrough in testing these massive
equations we designed several novel algorithms for generating Greechie diagrams
with an arbitrary number of blocks and atoms (currently testing with up to 50)
and for automated checking of equations on them. A way of obtaining complex
infinite dimensional Hilbert space from the Hilbert lattice equipped with
several additional conditions and without invoking the notion of state is
presented. Possible repercussions of the results to quantum computing problems
are discussed.

</DOC>
<DOC>
<DOCNO> 70583 </DOCNO>
Domain Walls in QCD


  QCD was shown to have a nontrivial vacuum structure due to the topology of
the theta = theta+2*pi*n parameter. As a result of this nontrivial topology, in
the large N_c limit, quasi-stable QCD domain walls appear, characterized by a
transition in the singlet eta' field. We discuss the physics of these QCD
domain walls as well as related axion domain walls and we present a new type of
axion wall which also contains an eta' transition. We argue that these domain
walls are topologically stable in the limit N_c->infinity and classically
stable for large but finite N_c, however, they can decay through a tunneling
process. We argue that the qualitative features of these QCD domain walls --
namely their classical stability -- persist to the realistic case of N_c=3 and
that it is at least possible that their lifetime could be macroscopically
large. If it is, then QCD domain walls could play an important role in the
evolution of early universe and may be detectable in energetic collisions such
as those at the Relativistic Heavy Ion Collider (RHIC).

</DOC>
<DOC>
<DOCNO> 71718 </DOCNO>
Large top mixing from extra dimensions


  Fermion mixing is conveniently described using the effective Lagrangian
formalism. We apply this approach to study top mixing in models with an
infinite tower of Kaluza-Klein fermion excitations. In the Randall-Sundrum
background with a boundary Higgs and phenomenologically viable values of the
model parameters, the only effect eventually observable is the loss of
universality of the top couplings. Their deviation from the SM predictions can
be up to 4 % if the five-dimensional Yukawa couplings times the AdS_5 curvature
scale are < 10.

</DOC>
<DOC>
<DOCNO> 9037 </DOCNO>
Three-Dimensional Ising Model and Transfer Matrices


  The use of a transfer matrix method to solve the 3D Ising model is
straightforwardly generalized from the 2D case. We follow B.Kaufman's approach.
No approximation is made, however the largest eigenvalue cannot be identified.
This problem comes from the fact that we follow the choice of directions of
2-dimensional rotations in the direct product space of the 2D Ising model such
that all eigenvalue equations reduce miraculously to only one equation. Other
choices of directions of 2-dimensional rotations for finding the largest
eigenvalue may lose this fascinating feature. Comparing the series expansion of
internal energy per site at the high temperature limit with the series obtained
from the computer graphic method, we find these two series have very similar
structures. A possible correct via a factor \Phi(x) is suggested to fit the
result of the graphic method.

</DOC>
<DOC>
<DOCNO> 116697 </DOCNO>
Multielectron ionization of atoms in strong fields: Classical analysis


  We consider the final stage of multiple ionization of atoms in a strong
linearly polarized laser field within a classical model. We propose that
non-sequential multiple ionization is dominated by symmetric escape from a
highly excited intermediate complex. For a configuration of N electrons with
C_Nv symmetry in a plane perpendicular to the electric field we analyze the
classical motion in phase space and discuss the final momentum distribution
parallel and perpendicular to the polarization axis. The results are in good
agreement with recent experiment of multiple ionization in Ne.

</DOC>
<DOC>
<DOCNO> 118672 </DOCNO>
Photometry and Photometric Redshifts of Faint Galaxies in the Hubble


  We present a catalog of photometry and photometric redshifts of 335 faint
objects in the HDF-S NICMOS field. The analysis is based on (1) infrared images
obtained with the Hubble Space Telescope (HST) using the Near Infrared Camera
and Multi-Object Spectrograph (NICMOS) with the F110W, F160W, and F222M
filters, (2) an optical image obtained with HST using the Space Telescope
Imaging Spectrograph (STIS) with no filter, and (3) optical images obtained
with the European Southern Observatory (ESO) Very Large Telescope (VLT) with U,
B, V, R, and I filters. The primary utility of the catalog of photometric
redshifts is as a survey of faint galaxies detected in the NICMOS F160W and
F222M images. The sensitivity of the survey varies significantly with position,
reaching a limiting depth of AB(16,000) ~ 28.7 and covering 1.01 arcmin^2 to
AB(16,000) = 27 and 1.05 arcmin^2 to AB(16,000) = 26.5. The catalog of
photometric redshifts identifies 21 galaxies (or 6% of the total) of redshift z
> 5, 8 galaxies (or 2% of the total) of redshift z > 10, and 11 galaxies (or 3%
of the total) of best-fit spectral type E/S0, of which 5 galaxies (or 1% of the
total) are of redshift z > 1.

</DOC>
<DOC>
<DOCNO> 11561 </DOCNO>
Optical mode crossings and the low temperature anomalies of SrTiO3


  Optical mode crossing is not a plausible explanation for the new broad
Brillouin doublet nor for the strong acoustic anomalies observed at low
temperatures in SrTiO3. Data presented to support that explanation are also
inconclusive.

</DOC>
<DOC>
<DOCNO> 100209 </DOCNO>
Convexity of multi-valued momentum map


  We extend the famous convexity theorem of Atiyah, Guillemin and Sternberg to
the case of non-Hamiltonian actions. We show that the image of a generalized
momentum map is a bounded polytope times a vector space. We prove that this
picture is stable for small perturbations of the symplectic form. We also
observe that an n-dimensional torus symplectic action on a 2n-dimensional
symplectic manifold, with fixed point, is Hamiltonian. We finally prove that an
extension of Kirwan's convexity theorem (for compact group actions) is also
true.

</DOC>
<DOC>
<DOCNO> 71078 </DOCNO>
Quark degrees of freedom in hadronic systems


  Quantum Chromodynamics (QCD) is the theory of the strong interactions. We
review descriptions of hadronic systems motivated by QCD, analyzing the recent
controversy between gluonic and bosonic degrees of freedom under the prism of
the Cheshire Cat Principle. Our analysis leads to an optimal scheme to study
hadronic properties. We proceed to extend this low energy descriptions to the
deep inelastic regime.

</DOC>
<DOC>
<DOCNO> 151837 </DOCNO>
Noncommutative perturbation in superspace


  We consider noncommutative {\cal N}=4 supersymmetric U(N) Yang-Mills theory.
Using the {\cal N}=1 superfield formalism and the background field method we
compute one-loop four point contributions to the effective action and compare
the result with the field theory limit from open string amplitudes in the
presence of a constant B-field.

</DOC>
<DOC>
<DOCNO> 118094 </DOCNO>
The Cosmological Quark-Hadron Transition and Massive Compact Halo


  One of the abiding mysteries in the so-called standard cosmological model is
the nature of the dark matter. It is universally accepted that there is an
abundance of matter in the universe which is non-luminous, due to their very
weak interaction, if at all, with the other forms of matter, excepting of
course the gravitational attraction. Speculations as to the nature of dark
matter are numerous, often bordering on exotics, and searches for such exotic
matter is a very active field of astroparticle physics at the dawn of the new
century. Nevertheless, in recent years, there has been experimental evidence
for at least one form of dark matter - the massive compact halo objects
detected through gravitational microlensing effects proposed by Paczynski some
years ago. To date, no clear consensus as to what these objects, referred to in
the literature as well as in the following by the acronym MACHO, are made of;
for a brief discussion of some of the suggestions, see below. In this work, we
show that they find a natural explanation as leftover relics from the putative
first order cosmic quark - hadron phase transition that is predicted by the
standard model of particle interactions to have occurred during the microsecond
epoch of the early universe.

</DOC>
<DOC>
<DOCNO> 9467 </DOCNO>
Carrier Scattering in Quantum Nanosystems


  Carrier interaction with phonons, photons, impurities, and electrons have
been addressed in semiconductor nanoscale systems with carrier confinement in
one and two dimensions subjected to a quantizing magnetic field and without it.

</DOC>
<DOC>
<DOCNO> 10620 </DOCNO>
Models of Superconductivity in Sr_2RuO_4


  Recent experimental data on purest Sr_2RuO_4 single crystals clearly indicate
the presence of nodes in the superconducting order parameter. Here, we consider
one special p-wave order parameter symmetry and two two-dimensional f-wave
order parameter symmetries having nodes within the RuO_2 plane. These states
reasonably describe both specific heat and penetration depth data. We calculate
the thermal conductivity tensor for these three states and compare the results
with recent thermal conductivity data. This allows us to single out one of
these states being consistent with both thermodynamic and thermal conductivity
data: the planar f-wave state having B_{1g} x E_u symmetry.

</DOC>
<DOC>
<DOCNO> 120039 </DOCNO>
NGC 4672: a new case of an early-type disk galaxy with an orthogonally


  We report the case of the early-type disk galaxy NGC 4672 as a new example of
a galaxy characterized by the orthogonal geometrical decoupling between bulge
and disk. The morphological features of this galaxy are discussed as well as
the velocity curves and velocity dispersion profiles of stars and ionized gas
along both its major and minor axis. We conclude that NGC 4672 has structural
(i.e., a bulge elongated perpendicularly to the disk) and kinematical (i.e., a
stellar core rotating perpendicularly to the disk) properties similar to those
of the Sa NGC 4698. The presence of the isolated core suggests that the disk
component is the end result of the acquisition of external material in polar
orbits around a pre-existing oblate spheroid as in the case of the ring
component of AM 2020-504, the prototype of polar ring ellipticals.

</DOC>
<DOC>
<DOCNO> 116924 </DOCNO>
Beam Dynamics Simulation for the CTF3 Drive-Beam Accelerator


  A new CLIC Test Facility (CTF3) at CERN will serve to study the drive beam
generation for the Compact Linear Collider (CLIC). CTF3 has to accelerate a 3.5
A electron beam in almost fully-loaded structures. The pulse contains more than
2000 bunches, one in every second RF bucket, and has a length of more than one
microsecond. Different options for the lattice of the drive-beam accelerator
are presented, based on FODO-cells and triplets as well as solenoids. The
transverse stability is simulated, including the effects of beam jitter,
alignment and beam-based correction.

</DOC>
<DOC>
<DOCNO> 178716 </DOCNO>
Relativistic Quark Spin Coupling Effects in the Correlations Between


  We investigate the effect of different relativistic spin couplings of
constituent quarks on nucleon electroweak properties. Within each quark spin
coupling scheme the correlations between static electroweak observables are
found to be independent of the particular shape of the momentum part of the
nucleon light-front wave function. The neutron charge form factor is very
sensitive to different choices of spin coupling schemes once the magnetic
moment is fitted to the experimental value. However, it is found rather
insensitive to the details of the momentum part of the three-quark wave
function model.

</DOC>
<DOC>
<DOCNO> 170016 </DOCNO>
Spatiotemporal Chaos of Soliton in a Generalized Skyrme Model with the


  The chiral symmetry-breaking term of the Skyrme model with massive pion is
modified to obtain the hedgehog profile function which is in best coincidence
with the kink-like profile function. For the modified Lagrangian, the minimum
of the energy of the B=2 twisty skyrmion configuration is lower than the values
for both the cases of the Skyrme Lagrangian with and without the non-modified
symmetry-breaking term. The equations of motion for the time-dependent hedgehog
of this model and for a generalizated Skyrme model including sixth-order
stabilizing term are derived and integrated nummerically. The time evolution of
soliton is obtained. We have observed the seft-exitation of soliton because of
the fast developement of fluctuation.

</DOC>
<DOC>
<DOCNO> 83351 </DOCNO>
Explaining away ambiguity: Learning verb selectional preference with


  This paper presents a Bayesian model for unsupervised learning of verb
selectional preferences. For each verb the model creates a Bayesian network
whose architecture is determined by the lexical hierarchy of Wordnet and whose
parameters are estimated from a list of verb-object pairs found from a corpus.
``Explaining away'', a well-known property of Bayesian networks, helps the
model deal in a natural fashion with word sense ambiguity in the training data.
On a word sense disambiguation test our model performed better than other state
of the art systems for unsupervised learning of selectional preferences.
Computational complexity problems, ways of improving this approach and methods
for implementing ``explaining away'' in other graphical frameworks are
discussed.

</DOC>
<DOC>
<DOCNO> 68700 </DOCNO>
Mass hierarchy and localization of gravity in extra time


  We consider Randall-Sundrum model with localized gravity, replacing the extra
compact space-like dimension by a time-like one. In this way the solution to
the hierarchy problem can be reconciled with a correct cosmological expansion
of the visible universe, just as a trivial result of the sign flip of
cosmological constants in the bulk and on the 3-branes relative to the case of
extra space-like dimension. Some phenomenological aspects of the proposed
scenario related to the tachyonic nature of Kaluza-Klein states of graviton are
also discussed.

</DOC>
<DOC>
<DOCNO> 174463 </DOCNO>
Fragment Kinetic Energies and Modes of Fragment Formation


  Kinetic energies of light fragments A <= 10 from the decay of target
spectators in 197Au 197Au collisions at 1000 MeV per nucleon have been measured
with high-resolution telescopes at backward angles. Except for protons and
apart from the observed evaporation components, the kinetic-energy spectra
exhibit slope temperatures of about 17 MeV, independent of the particle
species, but not corresponding to the thermal or chemical degrees of freedom at
breakup. It is suggested that these slope temperatures may reflect the
intrinsic Fermi motion and thus the bulk density of the spectator system at the
instant of becoming unstable.
  PACS numbers: 25.70.Pq, 21.65.+f, 25.70.Mn

</DOC>
<DOC>
<DOCNO> 100678 </DOCNO>
Analyticity of intersection exponents for planar Brownian motion


  We show that the intersection exponents for planar Brownian motions are
analytic. More precisely, let $B$ and $B'$ be independent planar Brownian
motions started from distinct points, and define the exponent $\xi (1,
\lambda)$ by $$ E[P[B[0,t] \cap B'[0,t] = \emptyset | B[0,t]]^\lambda] \approx
t^{-\xi(1, \lambda)/2}, t \to \infty. $$ Then the mapping $\lambda \mapsto \xi
(1, \lambda)$ is real analytic in $(0,\infty)$. The same result is proved for
the exponents $\xi (k, \lambda)$ where $k$ is a positive integer. In
combination with the determination of $\xi (k, \lambda)$ for integer $k \ge 1$
and real $\lambda \ge 1$ in our previous papers, this gives the value of $\xi
(k, \lambda)$ also for $\lambda \in (0,1)$ and the disconnection exponents
$\lim_{\lambda \searrow 0} \xi (k, \lambda)$. In particular, it shows that
$\lim_{\lambda \searrow 0} \xi(2, \lambda) = 2/3$ and concludes the proof of
the following result that had been conjectured by Mandelbrot: the Hausdorff
dimension of the outer boundary of $B[0,1]$ is 4/3 almost surely.

</DOC>
<DOC>
<DOCNO> 102867 </DOCNO>
Toric varieties whose blow-up at a point is Fano


  We classify smooth toric Fano varieties of dimension $n\geq 3$ containing a
toric divisor isomorphic to $\PP^{n-1}$. As a consequence of this
classification, we show that any smooth complete toric variety $X$ of dimension
$n\geq 3$ with a $T$-fixed point $x\in X$ such that the blow-up $B_x(X)$ of $X$
at $x$ is Fano is isomorphic either to $\PP^n$ or to the blow-up of $\PP^n$
along a $\PP^{n-2}$. As expected, such results are proved using toric Mori
theory due to Reid.

</DOC>
<DOC>
<DOCNO> 9969 </DOCNO>
Theoretical Model Upper Limit on The Lattice Parameter of Doped C60


  The results on the lattice instability, invoked by applying a negative
pressure on pure C60 solid, are described. The results of such a calculation
are used to correlate the experimentally achieved results on the
superconducting transition temperature Tc by doping C60 with alkali metals. A
simple model had been used already to interpret the bulk, structure and
thermodynamic properties Of C60 solids. As a result of this calculation an
upper limit on the lattice parameter results which is around 14.5A and is a
suggestion of an upper limit of Tc as well in doped C60.

</DOC>
<DOC>
<DOCNO> 8124 </DOCNO>
Analysis of stability of macromolecular clusters in dilute heteropolymer


  We study the formation of clusters consisting of several chains in dilute
solutions of amphiphilic heteropolymers. By means of the Gaussian variational
theory we show that in a region of the phase diagram within the conventional
two-phase coexistence region mesoglobules of equal size possess the lowest free
energy. Monte Carlo simulation confirms that the mesoglobules are stabilised
due to micro-phase separation, which introduces a preferred length scale. The
very existence of such mesoscopic structures is related to a delicate balance
of the energetic and entropic terms under the connectivity constraints. The
issue of size monodispersity and fluctuations for mesoglobules is investigated.

</DOC>
<DOC>
<DOCNO> 100582 </DOCNO>
Moment-angle complexes and combinatorics of simplicial manifolds


  Let $\rho:(D^2)^m\to I^m$ be the orbit map for the diagonal action of the
torus $T^m$ on the unit poly-disk $(D^2)^m$, $I^m=[0,1]^m$ is the unit cube.
Let $C$ be a cubical subcomplex in $I^m$. The moment-angle complex $\ma(C)$ is
a $T^m$-invariant bigraded cellular decomposition of the subset
$\rho^{-1}(C)\subset(D^2)^m$ with cells corresponding to the faces of $C$.
Different combinatorial problems concerning cubical complexes and related
combinatorial objects can be treated by studying the equivariant topology of
corresponding moment-angle complexes. Here we consider moment-angle complexes
defined by canonical cubical subdivisions of simplicial complexes. We describe
relations between the combinatorics of simplicial complexes and the bigraded
cohomology of corresponding moment-angle complexes. In the case when the
simplicial complex is a simplicial manifold the corresponding moment-angle
complex has an orbit consisting of singular points. The complement of an
invariant neighbourhood of this orbit is a manifold with boundary. The relative
Poincare duality for this manifold implies the generalized Dehn-Sommerville
equations for the number of faces of simplicial manifolds.

</DOC>
<DOC>
<DOCNO> 40110 </DOCNO>
First Observation of the $\Sigma_{c}^{*+}$ Baryon and a New Measurement


  Using data recorded with the CLEO II and CLEO II.V detector configurations at
the Cornell Electron Storage Rings, we report the first observation and mass
measurement of the $\Sigma_c^{*+}$ charmed baryon, and an updated measurement
of the mass of the $\Sigma_c^+$ baryon. We find
$M(\Sigma_c^{*+})-M(\Lambda_c^+)$= 231.0 +- 1.1 +- 2.0 MeV, and
$M(\Sigma_c^{+})-M(\Lambda_c^+)$= 166.4 +- 0.2 +- 0.3 MeV, where the errors are
statistical and systematic respectively.

</DOC>
<DOC>
<DOCNO> 39900 </DOCNO>
Direct Measurement of the W Boson Width in ppbar Collisions at roots =


  This Letter describes a direct measurement of the $W$ boson total decay
width, $\gw$, using the Collider Detector at Fermilab. The measurement uses an
integrated luminosity of $90\invpb$, collected during the 1994--1995 run of the
Fermilab Tevatron $p\pbar$ collider. The width is determined by normalizing
predicted signal and background distributions to 49844 $\wenu$ candidates and
21806 $\wmunu$ candidates in the transverse-mass region $M_T<200\gev$ and then
fitting the predicted shape to the 438 electron events and 196 muon events in
the high-$M_T$ region, $100<M_T<200\gev$. The result is
$\Gamma_W=2.04\pm0.11$(stat)$\pm0.09$(syst)GeV.

</DOC>
<DOC>
<DOCNO> 68038 </DOCNO>
Understanding Fields Using Strings: A Review for Particle Physicists


  In addition to being a prime candidate for a fundamental unified theory of
all interactions in nature, string theory provides a natural setting to
understand gauge field theories. This is linked to the concept of "D-branes":
extended, solitonic excitations of string theory which can be studied using
techniques of string theory and which support gauge fields localized along
their world-volumes. It follows that the techniques of string theory can be
very useful even for those particle physicists who are not specifically
interested in unification and/or quantum gravity. In this talk I attempt to
review how strings help us to understand fields. The discussion is restricted
to 3+1 spacetime dimensions.

</DOC>
<DOC>
<DOCNO> 119266 </DOCNO>
Discovery of Recurring Soft to Hard State Transitions in LMC X-3


  We present the analysis of an RXTE monitoring campaign of the canonical soft
state black hole candidates LMC X-1 and LMC X-3. In contrast to LMC X-1, which
does not exhibit any periodic spectral changes, we find that LMC X-3 exhibits
stron spectral variability on time scales of days to weeks. For typical RXTE
ASM count rates, the luminosity variations of LMC X-3 are due to changes of the
phenomenological disk blackbody temperature. During episodes of especially low
luminosity (ASM count rates < 0.6 counts/sec), kT strongly decreases and the
power law significantly hardens to a photon index of ~1.8. These changes are
consistent with state changes of LMC X-3 from the soft state to the canonical
hard state of galactic black hole candidates. We argue that the long term
variability of LMC X-3 might be due to a wind-driven limit cycle such as
discussed by Shields et al. (1986)

</DOC>
<DOC>
<DOCNO> 84536 </DOCNO>
Lax Tensors, Killing Tensors and Geometric Duality


  The solution of the Lax tensor equations in the case
$L_{\alpha\beta\gamma}=-L_{\beta\alpha\gamma}$ was analyzed. The Lax tensors on
the dual metrics were investigated. We classified all two dimensional metrics
having the symmetric Lax tensor $L_{\alpha\beta\gamma}$. The Lax tensors of the
flat space, Rindler system and its dual were found.

</DOC>
<DOC>
<DOCNO> 39914 </DOCNO>
A Search for the Electric Dipole Moment of the Tau-Lepton


  Using the ARGUS detector at the e+e- storage ring DORIS II, we have searched
for the real and imaginary part of the electric dipole formfactor d_tau of the
tau lepton in the production of tau pairs at q^2=100 GeV^2. This is the first
direct measurement of this CP violating formfactor. We applied the method of
optimised observables which takes into account all available information on the
observed tau decay products. No evidence for CP violation was found, and we
derive the following results: Re(d_tau)=(1.6+-.9)*10^(-16) ecm and
Im(d_tau)=(-0.2+-0.8)*10^(-16) ecm, where statistical and systematic errors
have been combined.

</DOC>
<DOC>
<DOCNO> 72127 </DOCNO>
Top Production and Decay at Linear Colliders: QCD Corrections


  We present the results of an exact calculation of gluon radiation in top
production and decay at high energy electron-positron colliders. We include all
spin correlations and interferences, the bottom quark mass, and finite top
width effects in the matrix element calculation. We study properties of the
radiated gluons and implications for top mass measurement. We also discuss
virtual corrections to the process.

</DOC>
<DOC>
<DOCNO> 119432 </DOCNO>
What hides at the center of the Sun ?


  The Standard Solar Model (SSM) and its basic assumption of an equation of
state of perfect gases for the plasmas of its interior is analyzed within the
new theoretical framework of QED coherent states. We find that for
$\frac{r}{r_{\odot}}\leq 0.3$ the SSM solution is unstable against collapse to
a dense, {\it cold} coherent core and as a result a large suppression of
$B^{8}$-neutrinos is obtained, apparently solving the long standing solar
neutrino problem.

</DOC>
<DOC>
<DOCNO> 67666 </DOCNO>
Lattice simulations of the strange quark mass and Fritzsch texture


  A number of numerical simulations of lattice gauge theory have indicated a
low mass of strange quark in 100 MeV range at the scale of $\mu=2$ GeV. In the
unquenched case, which is improved over the simulation in the quenched
approximation by the inclusion of $u$ and $d$ sea quark effects, one sees a
further downward trend. Here the fermion mass spectrum of the Fritzsch texture
is recalculated. In a single step supersymmetric GUT with $M_X \sim 10^{16}$
GeV such values of the strange quark mass can be obtained for low values of
$\tan \beta$. Experimental numbers $m^{pole}_t = 173 \pm 6$ GeV and $4.1 <
m_b(m_b) < 4.4$ GeV are used in this study. Since the scenario is
supersymmetric, gaugino loop diagrams contribute to the masses in addition to
usual tree level Yukawa contributions. Upper bound of the mixing parameter
$V_{cb}$ is taken at 0.045

</DOC>
<DOC>
<DOCNO> 170535 </DOCNO>
Localization of Macroscopic Object Induced by the Factorization of


  To account for the phenomenon of quantum decoherence of a macroscopic object,
such as the localization and disappearance of interference, we invoke the
adiabatic quantum entanglement between its collective states(such as that of
the center-of-mass (C.M)) and its inner states based on our recent
investigation. Under the adiabatic limit that motion of C.M dose not excite the
transition of inner states, it is shown that the wave function of the
macroscopic object can be written as an entangled state with correlation
between adiabatic inner states and quasi-classical motion configurations of the
C.M. Since the adiabatic inner states are factorized with respect to each parts
composing the macroscopic object, this adiabatic separation can induce the
quantum decoherence. This observation thus provides us with a possible solution
to the Schroedinger cat paradox

</DOC>
<DOC>
<DOCNO> 14141 </DOCNO>
Spontaneous Breaking of Translational Invariance and Spatial


  We further study the stochastic model discussed in Ref.[2] in which positive
and negative particles diffuse in an asymmetric, CP invariant way on a ring.
The positive particles hop clockwise, the negative counter-clockwise and
oppositely-charged adjacent particles may swap positions. We extend the
analysis of this model to the case when the densities of the charged particles
are not the same. The mean-field equations describing the model are coupled
nonlinear differential equations that we call the two-component Burgers
equations. We find roundabout weak solutions of these equations. These
solutions are used to describe the properties of the stationary states of the
stochastic model. The values of the currents and of various two-point
correlation functions obtained from Monte-Carlo simulations are compared with
the mean-field results. Like in the case of equal densities, one finds a pure
phase, a mixed phase and a disordered phase.

</DOC>
<DOC>
<DOCNO> 101949 </DOCNO>
Instantons on cylindrical manifolds and stable bundles


  Let Sigma be a smooth complex curve, and let S be the product ruled surface
Sigma \times CP^1. We prove a correspondence conjectured by Donaldson between
finite energy U(2)-instantons over the cylinder Sigma \times S^1 \times R, and
rank 2 holomorphic bundles over S whose restrictions to the divisors at
infinity are stable.

</DOC>
<DOC>
<DOCNO> 100545 </DOCNO>
Dequantization of real algebraic geometry on logarithmic paper


  On logarithmic paper some real algebraic curves look like smoothed broken
lines. Moreover, the broken lines can be obtained as limits of those curves.
The corresponding deformation can be viewed as a quantization, in which the
broken line is a classical object and the curves are quantum. This generalizes
to a new connection between algebraic geometry and the geometry of polyhedra,
which is more straight-forward than the other known connections and gives a new
insight into constructions used in the topology of real algebraic varieties.

</DOC>
<DOC>
<DOCNO> 118957 </DOCNO>
Starburst in the Ultra-luminous Galaxy Arp 220 - Constraints from


  We present observations of radio recombination lines from the starburst
galaxy Arp 220 at 1.4, 8.1, 84, 96 and 207 GHz (sensitive upper limit for the
1.4 GHz line and firm detections at the other frequencies), and the radio
continuum spectrum between 330 MHz and 207 GHz.
  We show that a model with three components of ionized gas with different
densities and area covering factors can consistently explain both RRL and
continuum data. The total mass of ionized gas in the three components is 3 x
10^7 M_sun requiring 3 x 10^5 O5 stars with a total Lyman continuum production
rate (NLyc) of 1.3 x 10^{55} photons /s. These values imply a dust extinction
A_V ~ 45 magnitudes and an SFR of ~240 M_sun/yr. The NLyc of ~3% associated
with the high density HII regions implies similar SFR at recent epochs. The
data is also consistent with multiple starbursts of very high SFR and short
durations. The derived value of 24 for the IR-excess favours a starburst rather
than an AGN as the origin of the observed FIR luminosity.
  (the abstract has been abridged)

</DOC>
<DOC>
<DOCNO> 120090 </DOCNO>
Nucleosynthesis in Massive Stars - Including All Stable Isotopes


  We present the first calculations to follow the evolution of all stable
isotopes (and their abundant radioactive progenitors) in a finely zoned stellar
model computed from the onset of central hydrogen burning through explosion as
a Type II supernova. The calculations were performed for a 15 solar mass Pop I
star using the most recently available set of experimental and theoretical
nuclear data, revised opacity tables, and taking into account mass loss due to
stellar winds. We find the approximately solar production of proton-rich
isotopes above a mass number of A=120 due to the gamma-process. We also find a
weak s-process, which along with the gamma-process and explosive helium and
carbon burning, produces nearly solar abundances of almost all nuclei from A=60
to 85. A few modifications of the abundances of heavy nuclei above mass 90 by
the s-process are also noted and discussed. New weak rates lead to significant
alteration of the properties of the presupernova core.

</DOC>
<DOC>
<DOCNO> 12922 </DOCNO>
Optimization of ground and excited state wavefunctions and van der Waals


  A quantum Monte Carlo method is introduced to optimize excited state trial
wavefunctions. The method is applied in a correlation function Monte Carlo
calculation to compute ground and excited state energies of bosonic van der
Waals clusters of upto seven particles. The calculations are performed using
trial wavefunctions with general three-body correlations.

</DOC>
<DOC>
<DOCNO> 10779 </DOCNO>
Fractional calculus and continuous-time finance II: the waiting-time


  We complement the theory of tick-by-tick dynamics of financial markets based
on a Continuous-Time Random Walk (CTRW) model recently proposed by Scalas et
al., and we point out its consistency with the behaviour observed in the
waiting-time distribution for BUND future prices traded at LIFFE, London.

</DOC>
<DOC>
<DOCNO> 99868 </DOCNO>
Associative triples and Yang-Baxter equation


  We introduce triples of associative algebras as a tool for building solutions
to the Yang-Baxter equation. It turns out that the class of R-matrices thus
obtained is related to a Hecke-like condition, which is formulated for
associative algebras with symmetric cyclic inner product. R-matrices for a
subclass of the $A_n$-type Belavin-Drinfel'd triples are derived in this way.

</DOC>
<DOC>
<DOCNO> 99503 </DOCNO>
Constructing Classical and Quantum Superconformal Algebras on the


  Motivated by recent progress on the correspondence between string theory on
anti-de Sitter space and conformal field theory, we address the question of
constructing space-time N extended superconformal algebras on the boundary of
AdS_3. Based on a free field realization of an affine SL(2|N/2) current
superalgebra residing on the world sheet, we construct explicitly the Virasoro
generators and the N supercurrents. N is even. The resulting superconformal
algebra has an affine SL(N/2) \otimes U(1) current algebra as an internal
subalgebra. Though we do not complete the general superalgebra, we outline the
underlying construction and present supporting evidence for its validity.
Particular attention is paid to its BRST invariance. In the classical limit
where the free field realization may be substituted by a differential operator
realization, we discuss further classes of generators needed in the closure of
the algebra. We find sets of half-integer spin fields, and for N>4 these
include generators of negative weights. An interesting property of the
construction is that for N>2 it treats the supercurrents in an asymmetric way.
Thus, we are witnessing a new class of superconformal algebras not obtainable
by conventional Hamiltonian reduction. The complete classical algebra is
provided in the case N=4 and is of a new and asymmetric form.

</DOC>
<DOC>
<DOCNO> 99622 </DOCNO>
Parallel connections and bundles of arrangements


  Let \A be a complex hyperplane arrangement, and let $X$ be a modular element
of arbitrary rank in the intersection lattice of \A. We show that projection
along $X$ restricts to a fiber bundle projection of the complement of \A to the
complement of the localization $\A_X$ of \A at $X$. The fiber is the decone of
a realization of the complete principal truncation of the underlying matroid of
\A along the flat corresponding to $X$. This result gives a topological
realization of results of Stanley, Brylawsky, and Terao on modular
factorization. We show that (generalized) parallel connection of matroids
corresponds to pullback of fiber bundles, clarifying the notion that all
examples of diffeomorphisms of complements of inequivalent arrangements result
from the triviality of the restriction of the Hopf bundle to the complement of
a hyperplane. The modular fibration result also yields a new method for
identifying $K(\pi,1)$ arrangements of rank greater than three. We identify a
new families of $K(\pi,1)$ arrangements, providing more evidence for the
conjecture that factored arrangements of arbitrary rank are $K(\pi,1)$.

</DOC>
<DOC>
<DOCNO> 120910 </DOCNO>
The Properties of Spiral Galaxies in Semi-Analytic Galaxy Formation


  We examine the present-day galaxy disk colors and star formation rates (SFRs)
in the semi-analytic model of Cole et al. (2000). We find that the fiducial
model is a good match to Kennicutt's (1998) observed global star formation law,
the color-based metallicity-magnitude correlation and the colors of
low-luminosity galaxies. The main limitation of the model, from the point of
view of present-day spirals, is that the optical colors of the disks of very
luminous spiral galaxies are too blue, even after accounting for the effects of
dust.

</DOC>
<DOC>
<DOCNO> 83343 </DOCNO>
Applying System Combination to Base Noun Phrase Identification


  We use seven machine learning algorithms for one task: identifying base noun
phrases. The results have been processed by different system combination
methods and all of these outperformed the best individual result. We have
applied the seven learners with the best combinator, a majority vote of the top
five systems, to a standard data set and managed to improve the best published
result for this data set.

</DOC>
<DOC>
<DOCNO> 151313 </DOCNO>
Connes-Kreimer-Epstein-Glaser Renormalization


  Causal perturbative renormalization within the recursive Epstein-Glaser
scheme involves extending, at each order, time-ordered operator-valued
distributions to coinciding points. This is achieved by a generalized Taylor
subtraction on test functions, which is transposed to distributions. We show
how the Epstein-Glaser recursive construction can, by means of a slight
modification of the Hopf algebra of Feynman graphs, be recast in terms of the
new Connes-Kreimer algebraic setup for renormalization. This is illustrated for
$\phi^4_4$-theory.

</DOC>
<DOC>
<DOCNO> 102633 </DOCNO>
Uniqueness of symplectic canonical class, surface cone and symplectic


  Let M be a closed oriented smooth 4-manifold admitting symplectic structures.
If M is minimal and has b^+=1, we prove that there is a unique symplectic
canonical class up to sign, and any real second cohomology class of positive
square is represented by symplectic forms. Similar results hold when M is not
minimal.

</DOC>
<DOC>
<DOCNO> 12508 </DOCNO>
d-Wave bipolaronic stripes and two energy scales in cuprates


  There is strong experimental evidence for pairing of polaronic carriers in
the normal state, two distinct energy scales, d-wave superconducting order
parameter,and charge segregation in the form of stripes in several cuprates.All
these remarkable phenomena might be unified in the framework of the bipolaron
theory as a result of the formation of mobile bipolarons in the normal state
and their Bose-Einstein condensation. Extending the BCS theory towards an
intermediate and strong-coupling regime we show that there are two energy
scales in this regime, a temperature independent incoherent gap and a
temperature dependent coherent gap combining into one temperature dependent
global gap. The temperature dependence of the gap and single particle (Giaver)
tunnelling spectra in cuprates are quantitatively described. A framework for
understanding of two distinct energy scales observed in Giaver tunnelling and
Andreev reflection experiments is provided. We suggest that both d-wave
superconducting order parameter and striped charge distribution result from the
bipolaron (center-of-mass) energy band dispersion rather than from any
particular interaction.

</DOC>
<DOC>
<DOCNO> 100494 </DOCNO>
Embeddings of relatively free groups into finitely presented groups


  We construct easy embeddings of relatively free groups (say the free Burnside
group, the free solvable group) into finitely presented groups. We introduce a
concept of verbal isoperimetric function of a group variety. We prove that if
the verbal Dehn function of a relatively free group is bounded by a polynomial
then the group can be embedded quasi-isometrically into a finitely presented
group with polynomial isoperimetric function. We also construct an easy
embedding of any Baumslag-Solitar solvable group into a finitely presented
group with polynomial Dehn function.

</DOC>
<DOC>
<DOCNO> 151846 </DOCNO>
Brane tunneling and the Brane World scenario


  Fate of branes in external fields is reviewed. Spontaneous creation of the
Brane World in $AdS_{5}$ with external field is described. The resulting Brane
World consists of a flat 4d spatially finite expanding Universe and curved
expanding "regulator" branes. All branes have a positive tension.

</DOC>
<DOC>
<DOCNO> 85166 </DOCNO>
Bianchi I Quantum cosmology in the Bergmann-Wagoner theory


  The Wheeler-DeWitt equation is considered in the context of generalized
scalar-tensor theories of gravitation for Bianchi type I cosmology. Exact
solutions are found for two selfinteracting potentials and arbitary coupling
function. The WKB wavefunctions are obtained and a family of solutions
satisfying the Hawking-Page regularity conditions of wormholes are found.

</DOC>
<DOC>
<DOCNO> 8097 </DOCNO>
Statistical thermodynamics of membrane bending mediated protein-protein


  Integral membrane proteins deform the surrounding bilayer creating
long-ranged forces that influence distant proteins. These forces can be
attractive or repulsive, depending on the proteins' shape, height, contact
angle with the bilayer, as well as the local membrane curvature. Although
interaction energies are not pairwise additive, for sufficiently low protein
density, thermodynamic properties depend only upon pair interactions. Here, we
compute pair interaction potentials and entropic contributions to the
two-dimensional osmotic pressure of a collection of noncircular proteins. In
contrast to direct short-ranged interactions such as van der Waal's,
hydrophobic, or electrostatic interactions, both local membrane Gaussian
curvature and protein ellipticity can induce attractions between two proteins
at distances of up to ten times their typical radii. For flat membranes,
bending rigidities of $\sim 30k_{B}T$, and moderate ellipticities, we find
thermally averaged attractive interactions of order $\sim 2k_{B}T$. These
interactions may play an important role in the intermediate stages of protein
aggregation.

</DOC>
<DOC>
<DOCNO> 102472 </DOCNO>
Forcing Isomorphism II


  If T has only countably many complete types, yet has a type of infinite
multiplicity then there is a ccc forcing notion Q such that, in any Q --generic
extension of the universe, there are non-isomorphic models M_1 and M_2 of T
that can be forced isomorphic by a ccc forcing. We give examples showing that
the hypothesis on the number of complete types is necessary and what happens if
`ccc' is replaced other cardinal-preserving adjectives. We also give an example
showing that membership in a pseudo-elementary class can be altered by very
simple cardinal-preserving forcings.

</DOC>
<DOC>
<DOCNO> 67660 </DOCNO>
Power Corrections to Event Shape Variables measured in ep Deep-Inelastic


  Deep-inelastic ep scattering data, taken with the H1 detector at HERA, are
used to study event shape variables over a large range of "relevant energy" Q
between 7 GeV and 100 GeV. Previously published analysis on thrust, jet
broadening, jet mass and C parameter are substantially refined and updated;
differential two-jet rates treated as event shapes are presented for the first
time.
  The Q dependence of the mean values is fit to second order calculations of
perturbative QCD applying power law corrections proportional to 1/Q^p to
account for hadronization effects. The concept of these power corrections is
tested by a systematic investigation in terms of a non-perturbative parameter
\bar{alpha}_{p-1} and the strong coupling constant.

</DOC>
<DOC>
<DOCNO> 7719 </DOCNO>
Fractional calculus and continuous-time finance


  In this paper we present a rather general phenomenological theory of
tick-by-tick dynamics in financial markets. Many well-known aspects, such as
the L\'evy scaling form, follow as particular cases of the theory. The theory
fully takes into account the non-Markovian and non-local character of financial
time series. Predictions on the long-time behaviour of the waiting-time
probability density are presented. Finally, a general scaling form is given,
based on the solution of the fractional diffusion equation.

</DOC>
<DOC>
<DOCNO> 116905 </DOCNO>
Design and Performance Simulations of the Bunch Compressor for the APS


  A magnetic bunch compressor has been designed and is being commissioned for
the APS linac to provide higher peak current for the LEUTL FEL. Of primary
concern is control of emittance growth due to coherent synchrotron radiation
(CSR). In addition, tolerances must be carefully evaluated in order to choose
the most stable operating conditions and ensure that the system can meet
operational goals. The computer code ELEGANT was used to design the bunch
compressor, set tolerances, and simulate likely performance. This 6-D code
includes a fast, simple simulation of CSR effects as well as longitudinal and
transverse wakefields. It also is believed to be unique in allowing
optimization of actual tracking results, such as bunch length, energy spread,
and emittance. Automated setup and analysis of matching and tolerance
simulations allowed consideration of numerous configurations without excessive
effort. This permitted choosing configurations that reduce sensitivity to
errors. Simulations indicate that emittance growth should be tolerable for up
to 600 A peak current, for which the normalized emittance will increase from 5
to about 6.8 pi-um. The simulations also provide predictions of emittance
variation with chicance parameters, which we hope to verify experimentally. *
Work supported by the U.S. Department of Energy, Office of Basic
 Energy Sciences, under Contract No. W-31-109-ENG-38.

</DOC>
<DOC>
<DOCNO> 8167 </DOCNO>
Charge and Spin Order in La2-xSrxNiO4 (x=0.275 and 1/3)


  We report polarized and unpolarized neutron diffraction measurements on
La2-xSrxNiO4 (x=0.275 and 1/3). The data for the spin ordered states are
consistent with a collinear spin model in which spins with S=1 are in the NiO2
plane and are uniformly rotated from the charge and spin stripe direction. The
deviation angle is larger for x=1/3 than for x=0.275. Furthermore, for x=1/3,
the ordered spins reorient below 50 K, which suggests a further lock-in of the
doped holes and their magnetic interactions with the S=1 spins.

</DOC>
<DOC>
<DOCNO> 151089 </DOCNO>
Near Hagedorn Dynamics of NS Fivebranes, or A New Universality Class of


  We analyze the thermodynamics of NS 5-branes as the temperature approaches
the NS 5-branes' Hagedorn temperature, and conclude that the dynamics of
``Little String Theory'' is a new universality class of interacting strings.
First we point out how to vary the temperature of the near extremal solution by
taking into account $g_s$ corrections. The Hagedorn temperature is shown to be
a limiting temperature for the theory. We then compare the thermodynamics to
that of a toy model made of free strings and find basic discrepancies. This
suggests a need for a new class of string interactions. We suggest that this
new universality class is characterized by a strong attractive
self-intersection interaction, which causes strings to be coiled. This model
might also explain why ``Little String Theories'' exist in at most 5+1
dimensions.

</DOC>
<DOC>
<DOCNO> 119597 </DOCNO>
The All Sky Automated Survey. A Catalog of almost 3900 variable stars


  Results of the first two years of observations using the All Sky Automated
Survey prototype camera are presented. More than 140 000 stars in 50 Selected
Fields covering 300 sq. degrees were monitored each clear night in the I-band
resulting in the ASAS Photometric I-band Catalog containing over 50 x 10^6
individual measurements. Nightly monitoring over 100 standard stars confirms
that most of our data remains within sigma_I=0.03 of the standard I system.
Search for the stars varying on the time scales longer than a few days revealed
almost 4000 variables (mostly irregular, pulsating and binaries) brighter than
13 mag. Only 155 of them are known variables included in GCVS, 56 were observed
by Hipparcos satellite (46 were marked as variable). Among the stars brighter
than I ~ 7.5 (which are saturated on our frames) we have found about 50
variables (12 are in GCVS, 6 other in Hipparcos (Perryman etal 1997) catalog).
Because of the large volume of the data we present here only selected tables
and light-curves, but the complete ASAS Catalog of Variable Stars (currently
divided into Periodic and Miscellaneous sections) and all photometric data are
available on the Internet http://www.astrouw.edu.pl/~gp/asas/asas.html or
http://archive.princeton.edu/~asas/

</DOC>
<DOC>
<DOCNO> 99542 </DOCNO>
Cascade Connections of Linear Systems and Factorizations of Holomorphic


  We show that the factorization problem $\theta (z)=\theta_2(z)\theta_1(z)$ is
solvable in the class of Hilbert space operator-valued functions holomorphic on
some neighbourhood of $z=0$ in $\nspace{C}{N}$ and having a zero at $z=0$ (here
$\theta (z)$ has a multiple zero at $z=0$). Such a factorization problem
becomes more complicated if we demand for $\theta (z), \theta_1(z)$ and
$\theta_2(z)$ to be Agler--Schur-class functions on the polydisk
$\nspace{D}{N}$ and for the factorization identity to hold in $\nspace{D}{N}$.
In this case we reduce it to the problem on the existence of a cascade
decomposition for certain multiparametric linear system $\alpha $--a
conservative realization of $\theta (z)$, and give the criterion for its
solvability in terms of common invariant subspaces for the $N$-tuple of main
operators of $\alpha $.

</DOC>
<DOC>
<DOCNO> 83254 </DOCNO>
Algorithmic Statistics


  While Kolmogorov complexity is the accepted absolute measure of information
content of an individual finite object, a similarly absolute notion is needed
for the relation between an individual data sample and an individual model
summarizing the information in the data, for example, a finite set (or
probability distribution) where the data sample typically came from. The
statistical theory based on such relations between individual objects can be
called algorithmic statistics, in contrast to classical statistical theory that
deals with relations between probabilistic ensembles. We develop the
algorithmic theory of statistic, sufficient statistic, and minimal sufficient
statistic. This theory is based on two-part codes consisting of the code for
the statistic (the model summarizing the regularity, the meaningful
information, in the data) and the model-to-data code. In contrast to the
situation in probabilistic statistical theory, the algorithmic relation of
(minimal) sufficiency is an absolute relation between the individual model and
the individual data sample. We distinguish implicit and explicit descriptions
of the models. We give characterizations of algorithmic (Kolmogorov) minimal
sufficient statistic for all data samples for both description modes--in the
explicit mode under some constraints. We also strengthen and elaborate earlier
results on the ``Kolmogorov structure function'' and ``absolutely
non-stochastic objects''--those rare objects for which the simplest models that
summarize their relevant information (minimal sufficient statistics) are at
least as complex as the objects themselves. We demonstrate a close relation
between the probabilistic notions and the algorithmic ones.

</DOC>
<DOC>
<DOCNO> 178403 </DOCNO>
Dissipative dynamics of fission in the framework of asymptotic expansion


  The dynamics of fission has been formulated by generalising the asymptotic
expansion of the Fokker-Planck equation in terms of the strength of the
fluctuations where the diffusion coefficients depend on the stochastic
variables explicitly. The prescission neutron multiplicities and the mean
kinetic energies of the evaporated neutrons have been calculated and compared
with the respective experimental data over a wide range of excitation energy
and compound nuclear mass. The mean and variance of the total kinetic energies
of the fission fragments have been calculated and compared with the
experimental values.

</DOC>
<DOC>
<DOCNO> 13106 </DOCNO>
The Folding Thermodynamics and Kinetics of Crambin Using an All-Atom


  We present a novel Monte Carlo simulation of protein folding, in which all
heavy atoms are represented as interacting hard spheres. This model includes
all degrees of freedom relevant to folding - all sidechain and backbone
torsions - and uses a Go potential. In this study, we focus on the 46 residue
alpha-beta protein crambin and two of its structural components, the helix and
helix hairpin. For a wide range of temperatures, we have recorded multiple
folding events of these three structures from random coils to native
conformations that differ by less than 1 A dRMS from their crystal structure
coordinates. The thermodynamics and kinetic mechanism of the helix-coil
transition obtained from our simulation shows excellent agreement with
currently available experimental and molecular dynamics data. Based on insights
obtained from folding its smaller structural components, a possible folding
mechanism for crambin is proposed. We observe that the folding occurs via a
cooperative, first order-like process, and that many folding pathways to the
native state exist. One particular sequence of events constitutes a
``fast-folding'' pathway where kinetic traps are avoided. At very low
temperatures, a kinetic trap arising from the incorrect packing of sidechains
was observed. These results demonstrate that folding to the native state can be
observed in a reasonable amount of time on desktop computers even when an
all-atom representation is used, provided the energetics sufficiently stabilize
the native state.

</DOC>
<DOC>
<DOCNO> 68730 </DOCNO>
The Role of the QCD Vacuum in the Heavy-Quark Bound State Dynamics


  The effective field theory approach allows a rigorous disentangling of high
and low energy effects in the heavy quarkonium dynamics. Focusing in particular
on the spectrum, we describe the nature of the non-perturbative effects and
discuss our present knowledge of them.

</DOC>
<DOC>
<DOCNO> 100496 </DOCNO>
On subgroups of R.Thompson's group F and other diagram groups


  In this paper, we continue our study of the class of diagram groups. Simply
speaking, a diagram is a labelled plane graph bounded by a pair of paths (the
top path and the bottom path). To multiply two diagrams, one simply identifies
the top path of one diagram with the bottom path of the other diagram, and
removes pairs of "reducible" cells. Each diagram group is determined by an
alphabet $X$, containing all possible labels of edges, a set of relations
${\cal R}=\{u_i=v_i\mid i=1,2,... \}$, containing all possible labels of cells,
and a word $w$ over $X$ -- the label of the top and bottom paths of diagrams.
Diagrams can be considered as 2-dimensional words, and diagram groups can be
considered as 2-dimensional analogue of free groups. In our previous paper, we
showed that the class of diagram groups contains many interesting groups
including the famous R. Thompson group $F$ (it corresponds to the simplest set
of relations $\{x=x^2 \}$), closed under direct and free products and some
other constructions. In this paper we study mainly subgroups of diagram groups.
We show that not every subgroup of a diagram group is itself a diagram group
(this answers a question from the previous paper). We prove that every
nilpotent subgroup of a diagram group is abelian, every abelian subgroup is
free, but even the Thompson group contains solvable subgroups of any degree. We
also study distortion of subgroups in diagram groups, including the Thompson
group. It turnes out that centralizers of elements and abelian subgroups are
always undistorted, but the Thompson group contains distorted soluble
subgroups.

</DOC>
<DOC>
<DOCNO> 116854 </DOCNO>
Theoretical study of the absorption spectra of the sodium dimer


  Absorption of radiation from the sodium dimer molecular states correlating to
Na(3s)-Na(3s) is investigated theoretically. Vibrational bound and continuum
transitions from the singlet X Sigma-g+ state to the first excited singlet A
Sigma-u+ and singlet B Pi-u states and from the triplet a Sigma-u+ state to the
first excited triplet b Sigma-g+ and triplet c Pi-g states are studied
quantum-mechanically. Theoretical and experimental data are used to
characterize the molecular properties taking advantage of knowledge recently
obtained from ab initio calculations, spectroscopy, and ultra-cold atom
collision studies. The quantum-mechanical calculations are carried out for
temperatures in the range from 500 to 3000 K and are compared with previous
calculations and measurements where available.

</DOC>
<DOC>
<DOCNO> 122934 </DOCNO>
Neutrino Emission from Neutron Stars


  We review the main neutrino emission mechanisms in neutron star crusts and
cores. Among them are the well-known reactions such as the electron-positron
annihilation, plasmon decay, neutrino bremsstrahlung of electrons colliding
with atomic nuclei in the crust, as well as the Urca processes and neutrino
bremsstrahlung in nucleon-nucleon collisions in the core. We emphasize recent
theoretical achievements, for instance, band structure effects in neutrino
emission due to scattering of electrons in Coulomb crystals of atomic nuclei.
We consider the standard composition of matter (neutrons, protons, electrons,
muons, hyperons) in the core, and also the case of exotic constituents such as
the pion or kaon condensates and quark matter. We discuss the reduction of the
neutrino emissivities by nucleon superfluidity, as well as the specific
neutrino emission produced by Cooper pairing of the superfluid particles. We
also analyze the effects of strong magnetic fields on some reactions, such as
the direct Urca process and the neutrino synchrotron emission of electrons. The
results are presented in the form convenient for practical use. We illustrate
the effects of various neutrino reactions on the cooling of neutron stars. In
particular, the neutrino emission in the crust is critical in setting the
initial thermal relaxation between the core and the crust. Finally, we discuss
the prospects of exploring the properties of supernuclear matter by confronting
cooling simulations with observations of the thermal radiation from isolated
neutron stars.

</DOC>
<DOC>
<DOCNO> 123012 </DOCNO>
Cosmological matter perturbations


  We investigate matter density perturbations in models of structure formation
with or without causal/acausal source. Under the fluid approximation in the
linear theory, we first derive full perturbation equations in flat space with a
cosmological constant $\Lambda$. We then use Green-function technique to obtain
analytic solutions for matter perturbations in a flat $\Lambda=0$ model. Some
incorrect solutions in the literature are corrected here. A simple yet accurate
extrapolation scheme is then proposed to obtain solutions in curved or
$\Lambda\neq 0$ cosmologies. Some general features of these solutions are
revealed. In particular, we analytically prove that the resulting matter
density perturbations are independent of the way the causal source was
compensated into the background contents of the universe when it was first
formed. We also use our Green-function solutions to investigate the
compensation mechanism for perturbations with causal seeds, and yield a
mathematically and physically explicit formin interpreting it. We found that
the compensation scale depends not only on the dynamics of the universe, but
also on the properties of the seeds near the horizon scale. It can be
accurately located by employing our Green functions.

</DOC>
<DOC>
<DOCNO> 11341 </DOCNO>
Extension of the Fluctuation-Dissipation theorem to the physical aging


  We present evidence in favor of the possibility of treating an
out-of-equilibrium supercooled simple liquid as a system in quasi-equilibrium.
Two different temperatures, one controlled by the external bath and one
internally selected by the system characterize the quasi-equilibrium state. The
value of the internal temperature is explicitly calculated within the inherent
structure thermodynamic formalism. We find that the internal temperature
controls the relation between the response to an external perturbation and the
long-time decay of fluctuations in the liquid.

</DOC>
<DOC>
<DOCNO> 122219 </DOCNO>
A Neutron-Star Identification for the High-Energy Gamma-ray Source 3EG


  In the error box of 3EG J1835+5918, the brightest as-yet unidentified EGRET
source at intermediate Galactic latitude, we find a weak, ultrasoft X-ray
source at energies E < 0.3 keV in the ROSAT All-Sky Survey. Deep optical
imaging at the location of this source, as pinpointed by an observation with
the ROSAT HRI, reveals a blank field to a limit of V > 25.2. The corresponding
lower limit on f_X/f_V is 300, which signifies that the X-ray source is
probably a thermally emitting neutron star. Considering our previous complete
multiwavelength survey of the 3EG J1835+5918 region which failed to find any
other notable candidate for identification with 3EG J1835+5918, we propose that
this X-ray source, RX J1836.2+5925, is a rotation-powered gamma-ray pulsar
which is either older or more distant than the prototype Geminga. We see
marginal evidence for variability between two ROSAT HRI observations. If real,
this would indicate that the X-ray emission has an external origin, perhaps due
to intermittent heating of the polar caps by a variable particle accelerator.
RX J1836.2+5925 could even be an old, recycled pulsar, which may nevertheless
have a high gamma-ray efficiency.

</DOC>
<DOC>
<DOCNO> 40215 </DOCNO>
Low-x Physics


  Low-x physics is reviewed, with particular emphasis on searches for
deviations from GLAP evolution of the parton densities. Although there are
several intriguing indications, both in HERA and Tevatron data, as yet there is
no unambiguous evidence for other than standard next-to-leading-order GLAP
evolution. The framework of dipole models and saturation of parton densities is
examined and confronted with the data. Although such models give a good
qualitative description of the data, so do other, more conventional,
explanations.

</DOC>
<DOC>
<DOCNO> 11084 </DOCNO>
Condensation of Hard Spheres Under Gravity: Exact Results in One


  We present exact results for the density profile of the one dimensional array
of N hard spheres of diameter D and mass m under gravity g. For a strictly one
dimensional system, the liquid-solid transition occurs at zero temperature,
because the close-pakced density, $\phi_c$, is one. However, if we relax this
condition slightly such that $phi_c=1-\delta$, we find a series of critical
temperatures T_c^i=mgD(N+1-i)/\mu_o with \mu_o=const, at which the i-th
particle undergoes the liquid-solid transition. The functional form of the
onset temperature, T_c^1=mgDN/\mu_o, is consistent with the previous result
[Physica A 271, 192 (1999)] obtained by the Enskog equation. We also show that
the increase in the center of mass is linear in T before the transition, but it
becomes quadratic in T after the transition because of the formation of solid
near the bottom.

</DOC>
<DOC>
<DOCNO> 100779 </DOCNO>
A tensor interpretation of the 2D Dirac equation


  We consider the Dirac equation in flat Minkowski 3-space and rewrite it as
the Maxwell equation in Minkowski 4-space with torsion. The torsion tensor is
defined as the dual of the electromagnetic vector potential. Our model clearly
distinguishes the electron and the positron without resorting to "negative
frequencies": we produce a real scalar invariant (charge) which indicates
whether we are looking at an electron or a positron. Another interesting
feature of our model is that the free electron and positron are identified with
gradient type solutions of the standard (torsion free) Maxwell equation; such
solutions have traditionally been disregarded on the grounds of gauge
invariance.

</DOC>
<DOC>
<DOCNO> 10801 </DOCNO>
Conserving and gapless model of the weakly interacting Bose gas


  The dielectric formalism is used to set up an approximate description of a
spatially homogeneous weakly interacting Bose gas in the collision-less regime,
which is both conserving and gap-less, and has coinciding poles of the
single-particle Green's function and the density autocorrelation function in
the Bose-condensed regime. The approximation takes into account the direct and
the exchange interaction in a consistent way.
 The fulfillment of the generalized Ward identities related to the conservation
of particle-number and the breaking of the gauge-symmetry is demonstrated. The
dynamics at long wavelengths is considered in detail below and above the
phase-transition, numerically and in certain limits also in analytical
approximations. The explicit form of the density autocorrelation function and
the Green's function is exhibited and discussed.

</DOC>
<DOC>
<DOCNO> 85352 </DOCNO>
The static cylinder, gyroscopes, the C metric, and all that


  The physical meaning of the Levi-Civita spacetime for some "critical" values
of the parameter sigma, is discussed in the light of gedanken experiments
performed with gyroscopes circumventing the axis of symmetry. The fact that
sigma=1/2 corresponds to flat space described from the point of view of an
accelerated frame of reference, led us to incorporate the C metric into
discussion. The interpretation of phi as an angle variable for any value of
sigma, appears to be at the origen of difficulties.

</DOC>
<DOC>
<DOCNO> 121623 </DOCNO>
Spectral analysis of multi mode pulsating sdB stars II. Feige 48, KPD


  Three members of the new class of pulsating sdB stars (sdBV or EC 14026
stars) are analysed from Keck HIRES spectra using line blanketed NLTE and LTE
model atmospheres. Atmospheric parameters (Teff, log g, He/H), metal abundances
and rotational velocities are determined. As is typical for sdB stars, all
programme stars are found to be helium deficient, with a He abundance ranging
from 1/80 solar for Feige 48 to 1/3 solar for PG 1219+534, probably due to
diffusion. Most metals are also depleted. The abundances of C, O, Ne, Mg, Al
and Si in the high gravity programme stars KPD 2109+4401 and PG 1219+534 are
considerably lower than in the lower gravity stars Feige 48 and PG 1605+072
which could be explained by an equilibrium between gravitational settling and
radiative levitation. Surprisingly iron is solar to within error limits in all
programme stars irrespective of their gravity, confirming predictions from
diffusion calculations. The metal lines are very sharp and allow the
microturbulent velocity to be constrained to be lower than 5km/s (KPD2109+4401,
PG 1219+534). Also the projected rotational velocities have to be very low
(vrot sini<10km/s). For Feige 48 the limits are even tighter (vmicro<=3km/s,
vrot sini<=5km/s).

</DOC>
<DOC>
<DOCNO> 84310 </DOCNO>
The Velocity of Gravitational Waves


  We examine the propagation of gravitational waves in the new field theory of
gravitation recently proposed by Novello-De Lorenci-Luciane (NDL). This
examination is done on a solvable case corresponding to a spherically symmetric
static configuration. We show that in NDL theory the velocity of gravitational
waves is lower than light velocity. We point out some consequences of this
result and suggest a possible scenario for its verification.

</DOC>
<DOC>
<DOCNO> 120556 </DOCNO>
The 2-point angular correlation function of 20,000 galaxies to V<23.5


  The UH8K wide field camera of the CFHT was used to image 0.68 deg^2 of sky.
  From these images, ~20,000 galaxies were detected to completeness magnitudes
V<23.5 and I<22.5. The angular correlation function of these galaxies is well
represented by the parameterization omega(theta) = A_W*theta^-delta. The slope
delta=-0.8 shows no significant variation over the range of magnitude. The
amplitude A_W decreases with increasing magnitude in a way that is most
compatible with a Lambda-CDM model (Omega_0 = 0.2, Lambda=0.8) with a
hierarchical clustering evolution parameter epsilon>0. We infer a best-fit
spatial correlation length of r_00= 5.85+/-0.5 h^-1 Mpc at z=0. The peak
redshift of the survey (I<22.5) is estimated to be z_peak~0.58, using the
blue-evolving luminosity function from the CFRS and the flat Lambda cosmology,
and r_0(z_peak)=3.5+/-0.5 h^-1 Mpc. We also detect a significant difference in
clustering amplitude for the red and blue galaxies, quantitatively measured by
correlation lengths of r_00=5.3+/-0.5 h^-1 Mpc and r_00=1.9+/-0.9 h^-1 Mpc
respectively, at z=0.

</DOC>
<DOC>
<DOCNO> 150893 </DOCNO>
Berry Connections and Induced Gauge Fields in Quantum Mechanics on


  Quantum mechanics on sphere $S^{n}$ is studied from the viewpoint that the
Berry's connection has to appear as a topological term in the effective action.
Furthermore we show that this term is the Chern-Simons term of gauge variables
that correspond to the extra degrees of freedom of the enlarged space.

</DOC>
<DOC>
<DOCNO> 12295 </DOCNO>
Boundary conditions and the entropy bound


  The entropy-to-energy bound is examined for a quantum scalar field confined
to a cavity and satisfying Robin condition on the boundary of the cavity. It is
found that near certain points in the space of the parameter defining the
boundary condition the lowest eigenfrequency (while non-zero) becomes
arbitrarily small. Estimating, according to Bekenstein and Schiffer, the ratio
$S/E$ by the $\zeta$-function, $(24\zeta (4))^{1/4}$, we compute $\zeta (4)$
explicitly and find that it is not bounded near those points that signals
violation of the bound. We interpret our results as imposing certain
constraints on the value of the boundary interaction and estimate the forbidden
region in the parameter space of the boundary conditions.

</DOC>
<DOC>
<DOCNO> 178431 </DOCNO>
A Calculation of Baryon Diffusion Constant in Hot and Dense Hadronic


  We evaluate thermodynamical quantities and transport coefficients of a dense
and hot hadronic matter based on an event generator URASiMA (Ultra-Relativistic
AA collision Simulator based on Multiple Scattering Algorithm). The statistical
ensembles in equilibrium with fixed temperature and chemical potential are
generated by imposing periodic boundary condition to the simulation of URASiMA,
where energy density and baryon number density is conserved. Achievement of the
thermal equilibrium and the chemical equilibrium are confirmed by the common
value of slope parameter in the energy distributions and the saturation of the
numbers of contained particles, respectively. By using the generated ensembles,
we investigate the temperature dependence and the chemical potential dependence
of the baryon diffusion constant of a dense and hot hadronic matter.

</DOC>
<DOC>
<DOCNO> 9455 </DOCNO>
Calculations of single particle spectra in density functional theory


  In the context of the density functional theory we consider the single
particle excitation spectra of electron systems. As a result, we have related
the single particle excitations with the eigenvalues of the corresponding
Kohn-Sham equations. In a case when the exchange correlation functional is
approximated by the exchange functional the coupling equations are very simple,
while the single particle spectra do not coincide neither with the eigenvalues
of the Kohn-Sham equations nor with the ones of the Hartree-Fock equations.

</DOC>
<DOC>
<DOCNO> 123333 </DOCNO>
Diffusion and the occurrence of hydrogen shell flashes in helium white


  We investigate the effects of element diffusion on the structure and
evolution of low-mass helium white dwarfs (WD). Attention is focused on the
occurrence of hydrogen shell flashes induced by diffusion processes during
cooling phases. Initial models from 0.406 to 0.161 solar masses are constructed
by applying mass loss rates at different stages of the RGB evolution of a solar
model. The multicomponent flow equations describing gravitational settling, and
chemical and thermal diffusion are solved and the diffusion calculations are
coupled to an evolutionary code. In addition, the same sequences are computed
but neglecting diffusion. We find that element diffusion strongly affects the
structure and cooling history of helium WD. In particular, diffusion induces
the occurrence of hydrogen shell flashes in models with masses ranging from
0.18 to 0.41 solar masses, which is in sharp contrast from the situation when
diffusion is neglected. In connection with the further evolution, these
diffusion-induced flashes lead to much thinner hydrogen envelopes, preventing
stable nuclear burning from being an appreciable energy source at advanced
stages of evolution. This implies much shorter cooling ages than in the case
when diffusion is neglected. These new WD models are discussed in light of
recent observational data of some millisecond pulsar systems with WD
companions. We find that age discrepancies between the predictions of standard
evolutionary models and such observations appear to be the result of ignoring
element diffusion in such models. Indeed, such discrepancies vanish when
account is made of diffusion.

</DOC>
<DOC>
<DOCNO> 11334 </DOCNO>
Quasi-periodic vs. irreversible dynamics of an optically confined


  We consider the evolution of a dilute Bose-Einstein condensate in an optical
trap formed by a doughnut laser mode. By solving a one dimensional
Gross-Pitaevskii equation and looking at the variance and the statistical
entropy associated with the position of the system we can study the dynamical
behavior of the system. It is shown that for small condensates nonlinear
revivals of the macroscopic wave function are expected. For sufficiently large
and dense condensates irreversible dynamics takes place for which revivals of
regular dynamics appear as predicted in [9]. These results are confirmed by a
two dimensional simulation in which the scales of energy associated with the
two different directions mimic the experimental situation.

</DOC>
<DOC>
<DOCNO> 123208 </DOCNO>
The emission regions in X-ray binaries: dipping as a diagnostic


  X-ray dipping in the black hole binary Cygnus X-1, the Galactic jet source
GRO J1655-40 and in low mass X-ray binaries is discussed. It is shown that
spectral analysis strongly constrains emission models. Measurement of dip
ingress/egress times allows the sizes of extended emission regions to be
determined, notably for the Accretion Disk Corona which is responsible for
Comptonization in X-ray binaries. In LMXB, the radius of the ADC is shown to be
between ~ 10^9 and ~ 5x10^10 cm, an appreciable fraction of the accretion disk
radius. This is inconsistent with Comptonization models requiring a localized
Comptonizing region, for example, in the immediate neighbourhood of the neutron
star. Results from a survey of LMXB using ASCA and BeppoSAX reveal an
approximate equality between the height of the blackbody emission region on the
neutron star and the height of the inner radiatively-supported disk, suggesting
either that there is a direct causal link, such as a radial accretion flow
between the inner disk edge and the star, or an indirect link, as in the case
of accretion flow creep on the surface of the neutron star as suggested by
Inogamov & Sunyaev. Finally, the survey shows that the blackbody cannot
originate on the accretion disk as the required inner radii in many sources are
substantially less than the neutron star radius.

</DOC>
<DOC>
<DOCNO> 9755 </DOCNO>
Metal-to-Insulator Crossover in the Low-Temperature Normal State of


  We measure the normal-state in-plane resistivity of La-doped Bi-2201 single
crystals at low temperatures by suppressing superconductivity with 60-T pulsed
magnetic fields. With decreasing hole doping, we observe a crossover from a
metallic to insulating behavior in the low-temperature normal state. This
crossover is estimated to occur near 1/8 doping, well inside the underdoped
regime, and not at optimum doping as reported for other cuprates. The
insulating regime is marked by a logarithmic temperature dependence of the
resistivity over two decades of temperature, suggesting that a peculiar charge
localization is common to the cuprates.

</DOC>
<DOC>
<DOCNO> 85138 </DOCNO>
Phase space path integral in curved space


  Phase space path integral is worked out in a riemannian geometry, by
employing a prescription for the infinitesimal propagator that takes riemannian
normal coordinates and momenta on an equal footing. The operator ordering
induced by this prescription leads to the DeWitt curvature coupling in the
Schrodinger equation.

</DOC>
<DOC>
<DOCNO> 118144 </DOCNO>
LASCO and EIT Observations of Coronal Mass Ejections


  We present a brief overview of LASCO and EIT observations of CMEs. We discuss
CME energetics, the relation of CMEs to streamers and conclude with some
insights into the source regions of CMEs.

</DOC>
<DOC>
<DOCNO> 9435 </DOCNO>
Non-collapsing solution bellow r_c for randomly forced particle


  We show that a non collapsing solution bellow $r_c$ can be constructed for
the dynamics of randomly forced particle interacting with a dissipative
boundary. The scaling analysis predicts a divergent collision rate at the
boundary for the non-collapsing solution. This prediction is tested
numerically.

</DOC>
<DOC>
<DOCNO> 13536 </DOCNO>
Odd-Frequency Density Waves: Non-Fermi-Liquid Metals with an Order


  We consider states with a charge- or spin-density wave order parameter which
is odd in frequency, so that the order parameter vanishes at zero frequency and
there is a conventional Fermi surface. Such states break translational symmetry
and, therefore, are not conventional Fermi liquids. In the odd-frequency
spin-density wave case, there are Goldstone bosons and the low-energy spectrum
is manifestly different from that of a Fermi liquid. We discuss a simple model
which gives rise to such ordered states. The frequency-dependence of the gap
leads to an unusual temperature dependence for various thermodynamic and
transport properties, notably the resistivity.

</DOC>
<DOC>
<DOCNO> 68006 </DOCNO>
QED out of matter


  The Wilsonian renormalization group implies that an arbitrary four
dimensional field theory with an ultraviolet cutoff is equivalent to a theory
which is renormalizable by power counting at energy scales much below the
cutoff. This applies to any theory including those with non-renormalizable
interactions as long as we fine-tune the mass parameters. We analyze two simple
models with current-current interactions but without elementary gauge fields
from this viewpoint. We show how to tune the parameters of the models so that
they become equivalent to QED at energies much below the cutoff.

</DOC>
<DOC>
<DOCNO> 85513 </DOCNO>
Renormalized black hole entropy in anti-de Sitter space via the "brick


  We consider the entropy of a quantum scalar field on a background black hole
geometry in asymptotically anti-de Sitter space-time, using the ``brick wall''
approach. In anti-de Sitter space, the theory has no infra-red divergences, and
all ultra-violet divergences can be absorbed into a renormalization of the
coupling constants in the one-loop effective gravitational Lagrangian. We then
calculate the finite renormalized entropy for the Schwarzschild-anti-de Sitter
and extremal Reissner-Nordstrom-anti-de Sitter black holes, and show that, at
least for large black holes, the entropy is entirely accounted for by the
one-loop Lagrangian, apart possibly from terms proportional to the logarithm of
the event horizon radius. For small black holes, there are indications that
non-perturbative quantum gravity effects become important.

</DOC>
<DOC>
<DOCNO> 70710 </DOCNO>
Anomalous Quartic Gauge Boson Couplings at Hadron Colliders


  We analyze the potential of the Fermilab Tevatron and CERN Large Hadron
Collider (LHC) to study anomalous quartic vector--boson interactions (photon
photon Z Z) and (photon photon W+ W-). Working in the framework of SU(2)_L X
U(1)_Y chiral Lagrangians, we study the production of photons pairs accompanied
by (e+e-), (e nu), and jet pairs to impose bounds on these new couplings,
taking into account the unitarity constraints. We compare our findings with the
indirect limits coming from precision electroweak measurements as well as with
presently available direct searches at LEPII. We show that the Tevatron Run II
can provide limits on these quartic limits which are of the same order of
magnitude as the existing bounds from LEPII searches. LHC will be able to
tighten considerably the direct constraints on these possible new interactions,
leading to more stringent limits than the presently available indirect ones.

</DOC>
<DOC>
<DOCNO> 40559 </DOCNO>
A QCD Survey: 0 < Q**2 < 10**5 Gev**2


  Selected, recent results, primarily from collider experiments but including
some fixed target experiments, are presented as a survey of Quantum
Chromodynamics (QCD). The concepts of leading order and next-to-leading order
QCD are introduced. Inclusive proton-antiproton jet and dijet production and
deep inelastic electron-proton scattering at very large momentum transfer are
shown to be in good agreement with perturbative QCD (pQCD). Dijet, three-jet
and multi-jet results from proton-antiproton, electron-proton, and
electron-electron colliders at moderate Q**2 are also compared to pQCD. BFKL
searches from all three colliders are discussed. Recent measurements of
structure functions and contributions to the parton distribution functions are
presented. New measurements of the strong coupling constant are summarized, the
world average is 0.1184 with an uncertainty of 0.0031.

</DOC>
<DOC>
<DOCNO> 85559 </DOCNO>
Braking--Radiation: An Energy Source for a Relativistic Fireball


  If the Schwarzschild black-hole is moving rectilinearly with uniform
3-velocity and suddenly stops, according to a distant observer, then we
demonstrate that this observer will see a spherical light--like shell or
"relativistic fireball" radiate outwards with energy equal to the original
kinetic energy of the black-hole.

</DOC>
<DOC>
<DOCNO> 72275 </DOCNO>
Evaluation of Self-Intersecting Wilson Loop in the Stochastic Vacuum


  A Wilson loop is evaluated within the stochastic vacuum model for the case
when the respective contour is self-intersecting and its size does not exceed
the correlation length of the vacuum. The result has the form of a certain
functional of the tensor area. It is similar to that for the
non-self-intersecting loop only when the contour is a plane one. Even for such
a contour, the obtained expression depends on the ratio of two functions
parametrizing the bilocal field strength correlator taken at the origin, which
is not so for the case of non-self-intersecting contour.

</DOC>
<DOC>
<DOCNO> 151286 </DOCNO>
D-branes, Cyclic Symmetry and Noncommutative Geometry


  We investigate the open string modes, describing the world-volume of a D
p-brane, for its cyclic symmetry in presence of a magnetic field. It is argued
that the constant coordinate modes receive non-perturbative correction. We show
that they introduce the notion of noncommutativity on the D p-brane
world-volume and make it UV-renormalizable. An analogy between cyclic symmetry
($\a'$-corrections) and the noncommutative geometry ($\Theta_A$-corrections) is
presented to explain some of the unusual IR phenomena often noticed in a
noncommutative theory.

</DOC>
<DOC>
<DOCNO> 100990 </DOCNO>
"Classical" flag varieties for quantum groups: the standard quantum


  We suggest a possible programme to associate geometric "flag-like" data to an
arbitrary simple quantum group, in the spirit of the noncommutative algebraic
geometry developed by Artin, Tate, and Van den Bergh. We then carry out this
programme for the standard quantum SL(n) of Drinfel'd and Jimbo, where the
varieties involved are certain T-stable subvarieties of the (ordinary) flag
variety.

</DOC>
<DOC>
<DOCNO> 71654 </DOCNO>
Chiral Perturbation Theory, Non-leptonic Kaon Decays, and the Lattice


  In this talk, I first motivate the use of Chiral Perturbation Theory in the
context of Lattice QCD. In particular, I explain how partially quenched QCD,
which has, in general, unequal valence- and sea-quark masses, can be used to
obtain real-world (i.e. unquenched) results for low-energy constants. In the
second part, I review how Chiral Perturbation Theory may be used to overcome
theoretical difficulties which afflict the computation of non-leptonic kaon
decay rates from Lattice QCD. I argue that it should be possible to determine
at least the O(p^2) weak low-energy constants reliably from numerical
computations of the K to pi and K to vacuum matrix elements of the
corresponding weak operators.

</DOC>
<DOC>
<DOCNO> 119090 </DOCNO>
The CNOC2 Field Galaxy Redshift Survey I: The Survey and the Catalog for


  The Canadian Network for Observational Cosmology (CNOC2) Field Galaxy
Redshift Survey is a spectroscopic/photometric survey of faint galaxies over
1.5 square degrees of sky with a nominal spectroscopic limit of R_c=21.5 mag.
The primary goals of the survey are to investigate the evolution of galaxy
clustering and galaxy populations over the redshift range of approximately 0.1
to 0.6. The survey area contains four widely separated patches on the sky with
a total spectroscopic sample of over 6000 redshifts and a photometric sample of
over 40,000 galaxies with 5-color photometry. We describe the survey and
observational strategies, multi-object spectroscopy mask design procedure, and
data reduction techniques for creating the spectroscopic-photometric catalogs.
We also discuss the derivations of various statistical weights for the redshift
sample which allow it to be used as a complete sample. As the initial release
of the survey data, we present the data set and some statistics for the Patch
CNOC0223+00.

</DOC>
<DOC>
<DOCNO> 151462 </DOCNO>
Holography in an Early Universe with Asymmetric Inflation


  We discuss the validity of the holographic principle in a $(4+n)$ dimensional
universe in an asymmetric inflationary phase.

</DOC>
<DOC>
<DOCNO> 7865 </DOCNO>
Higher Order Effects in the Dielectric Constant of Percolative


  The dielectric constant of a conductor-insulator mixture shows a pronounced
maximum above the critical volume concentration. Further experimental evidence
is presented as well as a theoretical consideration based on a phenomenological
equation. Explicit expressions are given for the position of the maximum in
terms of scaling parameters and the (complex) conductances of the conductor and
insulator. In order to fit some of the data, a volume fraction dependent
expression for the conductivity of the more highly conductive component is
introduced.

</DOC>
<DOC>
<DOCNO> 121215 </DOCNO>
Ultra-high angular resolution by gravitational microlensing


  The problem of restoration of the source brightness distribution from an
analysis of the stellar and AGNs microlensing light curves is investigated. In
case of microlensing of stars by a point-mass lens as well as for caustic
crossing events for binary lens the problem can be reduced to solution of the
Fredholm integral equation of the 1st kind. Concrete form of the kernel of this
equation depends on a type of the microlensing event. Assuming the circular
symmetry of the stellar disk the search for radial brightness distribution can
be carried out in the special compact sets of functions which correspond to the
physics of the problem. These sets include the non-negative functions that are
not increasing with increasing distance from the center of stellar disk and the
upwards convex non-negative functions. The brightness distribution for the AGNs
accretion disks is also circularly symmetric, but only in the locally co-moving
frame. Therefore, the kernel of integral equation that determined the AGN
microlensing light curve must take into account equally with the projection
effect on picture plane the influence of relativistic effects. The search for
solution of this equation can be carried out in the set of non-negative down
convex functions. The results of analysis of microlensing light curves for the
red giant MACHO Alert 95-30 and the A6 star MACHO 98-SMC-1 as well as the
results of numerical simulations for the AGN microlensing observations are
given.

</DOC>
<DOC>
<DOCNO> 12067 </DOCNO>
A Simple Model for Plastic Dynamics of a Disordered Flux Line Lattice


  We use a coarse-grained model of superconducting vortices driven through a
random pinning potential to study the nonlinear current-voltage (IV)
characteristics of flux flow in type II superconductors with pinning. In
experiments, the IV relation measures flux flow down a flux density gradient.
The work presented here treats this key feature explicitly. As the vortex
repulsion weakens, the vortex pile maintains a globally steeper slope,
corresponding to a larger critical current, for the same pinning potential. In
addition, the magnitude of the peak in the differential resistance falls as the
resistance peak shifts to higher currents. The model also exhibits so-called
"IV fingerprints", and crossover to Ohmic (linear) behavior at high currents.
Thus, many of the varieties of plastic behavior observed experimentally for
soft flux line systems in the ``peak regime'' are reproduced in numerical
simulations of the zero temperature model. The nonlinear transport behaviors
are related to the self-organized, large scale morphologies of the vortex river
flow down the slope of the vortex pile. These morphologies include isolated
filamentary channels, braided rivers, and flooded rivers. We propose that these
self-organized morphologies of flux flow down a flux gradient govern the
various plastic flow behaviors, including nonlinear IV characteristics,
observed in type II superconductors.

</DOC>
<DOC>
<DOCNO> 121649 </DOCNO>
The McKee/Ostriker Model: Paradigm?


  We summarize the current observational status of the interstellar medium in
terms of the McKee/Ostriker model. We find both agreement and
disagreement---hence the title of the paper. Some of the newest observations
differ from older ones, which underscores the need for both more and better
data

</DOC>
<DOC>
<DOCNO> 84978 </DOCNO>
Gravitational Goldstone fields from affine gauge theory


  In order to facilitate the application of standard renormalization
techniques, gravitation should be decribed, if possible, in pure connection
formalism, as a Yang-Mills theory of a certain spacetime group, say the
Poincare or the affine group. This embodies the translational as well as the
linear connection. However, the coframe is not the standard Yang-Mills type
gauge field of the translations, since it lacks the inhomogeneous gradient term
in the gauge transformations. By explicitly restoring the "hidden" piece
responsible for this behavior within the framework of nonlinear realizations,
the usual geometrical interpretation of the dynamical theory becomes possible,
and in addition one can avoid the metric or coframe degeneracy which would
otherwise interfere with the integrations within the path integral. We claim
that nonlinear realizations provide a general mathematical scheme clarifying
the foundations of gauge theories of spacetime symmetries. When applied to
construct the Yang-Mills theory of the affine group, tetrads become identified
with nonlinear translational connections; the anholonomic metric does not
constitute any more an independent gravitational potential, since its degrees
of freedom reveal to correspond to eliminable Goldstone bosons. This may be an
important advantage for quantization.

</DOC>
<DOC>
<DOCNO> 121415 </DOCNO>
Establishing The GZK Cutoff With Ultra High Energy Tau Neutrinos


  The cosmic ray spectrum has been shown to extend well beyond 10^20 eV. With
nearly 20 events observed in the last 40 years, it is now established that
particles are accelerated or produced in the universe with energy near 10^21
eV. In all production models neutrinos and photons are part of the cosmic ray
flux. In acceleration models (bottom-up models), they are produced as
secondaries of the possible interactions of the accelerated charged particle,
in direct production models (top-down models) they are a dominant fraction of
the decay chain. In addition, hadrons above the GZK threshold energy will also
produce, along their path in the Universe, neutrinos and photons as secondaries
of the pion photo-production processes. Therefore, photons and in particular
neutrinos, are very distinctive signatures of the nature and distribution of
the potential sources of ultra high energy cosmic rays. In the following we
expose the identification capabilities of the Auger observatories. In the
hypothesis of nu_mu-->nu_tau oscillations with full mixing, special emphasis is
placed on the observation of tau neutrinos, with which Auger is able to
establish the GZK cutoff as well as to provide a strong and model independant
constraint on the top-down sources of ultra high energy cosmic rays.

</DOC>
<DOC>
<DOCNO> 8458 </DOCNO>
The influence of critical behavior on the spin glass phase


  We have argued in recent papers that Monte Carlo results for the equilibrium
properties of the Edwards-Anderson spin glass in three dimensions, which had
been interpreted earlier as providing evidence for replica symmetry breaking,
can be explained quite simply within the droplet model once finite size effects
and proximity to the critical point are taken into account. In this paper, we
show that similar considerations are sufficient to explain the Monte Carlo data
in four dimensions. In particular, we study the Parisi overlap and the link
overlap for the four-dimensional Ising spin glass in the Migdal-Kadanoff
approximation. Similar to what is seen in three dimensions, we find that
temperatures well below those studied in Monte Carlo simulations have to be
reached before the droplet model predictions become apparent. We also show that
the double-peak structure of the link overlap distribution function is related
to the difference between domain-wall excitations that cross the entire system
and droplet excitations that are confined to a smaller region.

</DOC>
<DOC>
<DOCNO> 85636 </DOCNO>
Large-scale cosmological perturbations on the brane


  In brane-world cosmologies of Randall-Sundrum type, we show that evolution of
large-scale curvature perturbations may be determined on the brane, without
solving the bulk perturbation equations. The influence of the bulk
gravitational field on the brane is felt through a projected Weyl tensor which
behaves effectively like an imperfect radiation fluid with anisotropic stress.
We define curvature perturbations on uniform density surfaces for both the
matter and Weyl fluids, and show that their evolution on large scales follows
directly from the energy conservation equations for each fluid. The total
curvature perturbation is not necessarily constant for adiabatic matter
perturbations, but can change due to the Weyl entropy perturbation. To relate
this curvature perturbation to the longitudinal gauge metric potentials
requires knowledge of the Weyl anisotropic stress which is not determined by
the equations on the brane. We discuss the implications for large-angle
anisotropies on the cosmic microwave background sky.

</DOC>
<DOC>
<DOCNO> 85497 </DOCNO>
Calculating Gravitational Radiation from Collisions


  The development of both ground- and space-based gravitational wave detectors
provides new opportunities to observe the radiation from binaries containing
neutron stars and black holes. Numerical simulations in 3-D are essential for
calculating the coalescence waveforms, and comprise some of the most
challenging problems in astrophysics today. This article briefly reviews the
current status of efforts to calculate black hole and neutron star
coalescences, and highlights challenges for the future.

</DOC>
<DOC>
<DOCNO> 7613 </DOCNO>
Non-linear Transport in Quantum-Hall Smectics


  Recent transport experiments have established that two-dimensional electron
systems with high-index partial Landau level filling, $\nu^{*} =\nu - \lbrack
\nu \rbrack$, have ground states with broken orientational symmetry. In a
mean-field theory, the broken symmetry state consists of electron stripes with
local filling factor $\lbrack \nu \rbrack + 1 $, separated by hole stripes with
filling factor $\lbrack \nu \rbrack$. We have recently developed a theory of
these states in which the electron stripes are treated as one-dimensional
electron systems coupled by interactions and described by using a Luttinger
liquid model. Among other things, this theory predicts non-linearities of
opposite sign in easy and hard direction resistivities. In this article we
briefly review our theory, focusing on its predictions for the dependence of
non-linear transport exponents on the separation $d$ between the
two-dimensional electron system and a co-planar screening layer.

</DOC>
<DOC>
<DOCNO> 151275 </DOCNO>
The Non-Abelian Born-Infeld Action and Noncommutative gauge theory


  In this paper we explicitly show the equivalence between the non-Abelian
Born-Infeld action, which was proposed by Tseytlin as an effective action on
several D-branes, and its noncommutative counterpart for slowly varying fields.
This confirms the equivalence between the two descriptions of the D-branes
using an ordinary gauge theory with a constant B field background and a
noncommutative gauge theory, claimed by Seiberg and Witten. We also construct
the general forms of the 2 n-derivative terms for non-Abelian gauge fields
which are consistent with the equivalence in the approximation of neglecting (2
n+2)-derivative terms.

</DOC>
<DOC>
<DOCNO> 118979 </DOCNO>
2MASS Extended Source Catalog: Overview and Algorithms


  The 2 Micron All-Sky Survey (2MASS) will observe over one-million galaxies
and extended Galactic sources covering the entire sky at wavelengths between 1
and 2 microns. The survey catalog will have both high completeness and
reliability down to J = 15.0 and Ks = 13.5 mag, equivalent to 1.6 mJy and 2.9
mJy, respectively. This paper describes the basic algorithms used to detect and
characterize extended sources in the 2MASS database and catalog. Critical
procedures include tracking the point spread function, image background
removal, artifact removal, photometry and basic parameterization, star-galaxy
discrimination and object classification using a decision tree technique.
Examples of extended sources encountered in 2MASS are given.

</DOC>
<DOC>
<DOCNO> 39639 </DOCNO>
Decay phi->pi+pi-


  The process e+e- ->pi+pi- has been studied with the SND detector at VEPP-2M
e+e- collider in the vicinity of phi(1020) resonance. From the analysis of the
energy dependence of measured cross section the branching ratio
B(phi->pi+pi-)=(7.1+-1.1+-0.9)*10^{-5} and the phase psi_pi=-(34+-4+-3)degrees
of interference with the non-resonant pi+pi- production amplitude were
obtained.

</DOC>
<DOC>
<DOCNO> 9530 </DOCNO>
Microscopic description of d-wave superconductivity by Van Hove nesting


  We devise a computational approach to the Hubbard model that captures the
strong coupling dynamics arising when the Fermi level is at a Van Hove
singularity in the density of states. We rely on an approximate degeneracy
among the many-body states accounting for the main instabilities of the system
(antiferromagnetism, d-wave superconductivity). The Fermi line turns out to be
deformed in a manner consistent with the pinning of the Fermi level to the Van
Hove singularity. For a doping rate $\delta \sim 0.2$, the ground state is
characterized by d-wave symmetry, quasiparticles gapped only at the
saddle-points of the band, and a large peak at zero momentum in the d-wave
pairing correlations.

</DOC>
<DOC>
<DOCNO> 39675 </DOCNO>
Particle Interferometry from 40 MeV to 40 TeV


  We review particle interferometry before 2000, including: basics and
formalism of quantum-statistical correlations; model-independent analysis of
short-range correlations; Coulomb wave-function corrections and the core/halo
picture for $n$-particle Bose-Einstein correlations; graph rules to calculate
these correlations even with partial coherence in the core; particle
interferometry in $e^+e^-$ collisions including the Andersson-Hofmann model;
invariant Buda-Lund particle interferometry; Buda-Lund, Bertsch-Pratt and
Yano-Koonin-Podgoretskii parameterizations; Buda-Lund hydro model and its
applications to (\pi/K)+p and Pb+Pb collisions at CERN SPS, as well as to low
energy heavy ion collisions; binary source formalism and the related
oscillations in the two-particle Bose-Einstein and Fermi-Dirac correlation
functions; experimental signs of expanding rings of fire and shells of fire in
particle and heavy ion physics and their similarity to planetary nebulae in
stellar astronomy; signal of partial restoration of the U_A(1) symmetry
restoration in the two-pion correlation function; back-to-back correlations of
bosons with in-medium mass modifications; and the analytic solution of the
pion-laser model.

</DOC>
<DOC>
<DOCNO> 152480 </DOCNO>
Evaporation of charged black holes near extremality


  The AdS_2\timesS^2 geometry of near-extremal Reissner-Nordstrom black holes
can be described by an effective solvable model which allows to follow
analytically the evaporation process including the backreaction. We find that
an infinite amount of time is required for the black hole to decay to
extremality.

</DOC>
<DOC>
<DOCNO> 151736 </DOCNO>
Localization of Gravitino on a Brane


  We show how the spin 3/2 gravitino field can be localized on a brane in a
general framework of supergravity theory. Provided that a scalar field coupled
to the Rarita-Schwinger field develops an vacuum expectation value (VEV) whose
phase depends on the 'radial' coordinate in extra internal space, the gravitino
is localized on a brane with the exponentially decreasing warp factor by
selecting an appropriate value of the VEV.

</DOC>
<DOC>
<DOCNO> 84259 </DOCNO>
Warm inflation with coupled thermal quantum fluctuations: a new


  I consider a new semiclassical expansion for the inflaton field in the
framework of warm inflation scenario. The fluctuations of the matter field are
considered as thermally coupled with the particles of the thermal bath. This
coupling parameter depends on the temperature of the bath. The power spectrum
remains invariant under this new semiclassical expansion for the inflaton.
However, I find that the thermal component of the amplitude for the primordial
field fluctuations should be very small at the end of inflation.

</DOC>
<DOC>
<DOCNO> 12144 </DOCNO>
Commutation Relations in Mesoscopic Electric Circuits


  In the talk, I briefly demonstrate the quantum theory for mesoscopic electric
circuits and its applications. In the theory, the importance of the charge
discreteness in a mesoscopic electric circuit is addressed. As a result, a new
kind of commutation relation for electric charge and current occurred
inevitably. The charge representation, canonical current representation and
pseudo-current representation are discussed extensively. It not only provides a
concrete realization of mathematical models which discuss the space
quantization in high energy physics and quantum gravity but also presents a
sequence of applications in condensed matter physics from a different point of
view. A possible generalization to coupled circuits is also proposed.

</DOC>
<DOC>
<DOCNO> 68578 </DOCNO>
Mass Matrices in E6 Unification


  We study a supersymmetric E6 grand unified model in which the SU(5) 5^*
components are twisted in the third generation 27. Supplementing the adjoint
Higgs field to a model analyzed previously, we calculate the mass matrices for
the up and down quarks and charged leptons. Although the number of free
parameters is less than that of observables, an overall fitting to the observed
masses and mixing angles is shown to be possible. Most notably, we find two
novel, parameter-independent relations between the lepton 2-3 mixing angle and
the quark masses and CKM mixing angles that are in good agreement with the
large lepton mixing recently observed.

</DOC>
<DOC>
<DOCNO> 119733 </DOCNO>
The Rapidly Fading Afterglow from the Gamma-Ray Burst of 1999 May 6


  We report on the discovery of the radio afterglow from the gamma-ray burst
(GRB) of 1999 May 6 (GRB 990506) using the Very Large Array (VLA). The radio
afterglow was detected at early times (1.5 days), but began to fade rapidly
sometime between 1 and 5 days after the burst. If we attribute the radio
emission to the forward shock from an expanding fireball, then this rapid onset
of the decay in the radio predicts that the corresponding optical transient
began to decay between 1 and 5 minutes after the burst. This could explain why
no optical transient for GRB 990506 was detected in spite of numerous searches.
The cause of the unusually rapid onset of the decay for the afterglow is
probably the result of an isotropically energetic fireball expanding into a low
density circumburst environment. At the location of the radio afterglow we find
a faint (R ~ 24 mag) host galaxy with a double morphology.

</DOC>
<DOC>
<DOCNO> 12969 </DOCNO>
Electron-Hole Systems in Narrow Quantum Wells: Excitonic Complexes and


  The energy and photoluminescence (PL) spectra of a two-dimensional electron
gas (2DEG) interacting with a valence-band hole are studied in the
high-magnetic-field limit as a function of the filling factor nu and the
separation $d$ between the electron and hole layers. For d smaller than the
magnetic length lambda, the hole binds one or more electrons to form neutral
(X) or charged (X-) excitons, and PL probes the lifetime and binding energies
of these complexes rather than the original correlations of the 2DEG. The
low-lying states can be understood in terms of Laughlin-type correlations among
the constituent negatively charged Fermions (electrons and X-'s). For d large
compared to lambda, the electron--hole interaction is not strong enough to bind
a full electron, and fractionally charged excitons (bound states of the hole
and one or more Laughlin quasielectrons) hQEn are formed. The PL selection rule
associated with rotational invariance (conservation of L) is only weakly
violated in the interacting plasma, and the position and oscillator strengths
of PL lines can be predicted and compared with numerical calculations.

</DOC>
<DOC>
<DOCNO> 150482 </DOCNO>
Space-Time Quantization and Nonlocal Field Theory -Relativistic Second


  We propose relativistic second quantization of matrix model of D particles in
a general framework of nonlocal field theory based on Snyder-Yang's quantized
space-time. Second-quantized nonlocal field is in general noncommutative with
quantized space-time, but conjectured to become commutative with light cone
time $X^+$. This conjecture enables us to find second-quantized Hamiltonian of
D particle system and Heisenberg's equation of motion of second-quantized {\bf
D} field in close contact with Hamiltonian given in matrix model. We propose
Hamilton's principle of Lorentz-invariant action of {\bf D} field and
investigate what conditions or approximations are needed to reproduce the above
Heisenberg's equation given in light cone time. Both noncommutativities
appearing in position coordinates of D particles in matrix model and in
quantized space-time will be eventually unified through second quantization of
matrix model.

</DOC>
<DOC>
<DOCNO> 13179 </DOCNO>
Evidence for novel polaronic Fermi-liquid in doped oxides


  The modern multi-polaron theory predicts a polaronic Fermi-liquid state, but
such a state has not been unambigously confirmed by experiment so far. Here we
report theoretical and experimental studies of the isotope effects on the low
temperature kinetic properties of the doped ferromagnetic manganites. Our
results provide clear evidence for a novel polaronic Fermi-liquid state in
doped oxides.

</DOC>
<DOC>
<DOCNO> 69712 </DOCNO>
When is it possible to use perturbation technique in field theory ?


  The vector pion form factor is used as an example to analyze this question.
Given the experimental radius of the pion, the crucial question is whether
perturbative methods could be used for the effective chiral lagrangian to
calculate the pion form factor. Our analysis shows that the pion rms radius is
far too large (or the related rho resonance mass is too low) for the
perturbation theory to be valid.

</DOC>
<DOC>
<DOCNO> 10599 </DOCNO>
Multi-band Gutzwiller wave functions for itinerant ferromagnetism


  Multi-band Gutzwiller-correlated wave functions reconcile the contrasting
concepts of itinerant band electrons versus electrons localized in partially
filled atomic shells. The approximate evaluation of these variational ground
states becomes exact in the limit of large coordination number. The result
allows the identification of quasi-particle band structures for correlated
electron systems. As a first application, we summarize a study of itinerant
ferromagnetism in a two-band model, thereby elucidating the co-operation of the
Coulomb repulsion and the Hund's-rule exchange. Then, we present results of
calculations for ferromagnetic nickel, using a realistic 18 spin-orbital basis
of 4s, 4p and 3d valence electrons. Good agreement with the experimental
ground-state properties of nickel is obtained. In particular, the
quasi-particle energy bands agree much better with the photo-emission and Fermi
surface data than the band structure obtained from spin-density functional
theory. Finally, we present results for the variational spinwave dispersion for
our two-band model.

</DOC>
<DOC>
<DOCNO> 13949 </DOCNO>
Two-particle self-consistent approximation, pseudogap and


  In this thesis, I present a non-perturbative approach to the single-band
attractive Hubard model which is an extension of previous work by Vilk and
Tremblay on the repulsive model. Exact results are derived in the general
context of functional derivative approaches to many-body theories. The first
step of the approximation is based on a local field type ansatz. All physical
quantities can be expressed as a function of double-occupancy (in addition to
temperature and filling). Double-occupancy is determined without adjustable
parameter by imposing the Pauli principle and a crucial sum-rule, making the
first step of the approximation Two-Particle Self-Consistent. The final
expression for the self-energy is obtained by calculating the low-frequency
part of the exact expression with the two-particle correlation, Green function
and renormalized vertex obtained in the first step of the approximation. The
Mermin-Wagner theorem in two dimensions is automatically satisfied. Application
of this non-perturbative many-body approach to the intermediate coupling regime
shows quantitative agreement with quantum Monte Carlo calculations. Both
approaches predict the existence of a pseudogap in the single-particle spectral
weight. I present some physical properties, such as correlation lengths,
superfluid density, and characteristic pair fluctuation energy, to highlight
the origin of the pseudogap in the weak to intermediate coupling regime. These
results suggest that two-dimensional systems that are described by a symmetry
group larger than SO(2) could have a larger region of pseudogap behavior.
High-temperature superconductors may belong to that category of systems.

</DOC>
<DOC>
<DOCNO> 84519 </DOCNO>
Hadamard Regularization


  Motivated by the problem of the dynamics of point-particles in high
post-Newtonian (e.g. 3PN) approximations of general relativity, we consider a
certain class of functions which are smooth except at some isolated points
around which they admit a power-like singular expansion. We review the concepts
of (i) Hadamard ``partie finie'' of such functions at the location of singular
points, (ii) the partie finie of their divergent integral. We present and
investigate different expressions, useful in applications, for the latter
partie finie. To each singular function, we associate a partie-finie (Pf)
pseudo-function. The multiplication of pseudo-functions is defined by the
ordinary (pointwise) product. We construct a delta-pseudo-function on the class
of singular functions, which reduces to the usual notion of Dirac distribution
when applied on smooth functions with compact support. We introduce and analyse
a new derivative operator acting on pseudo-functions, and generalizing, in this
context, the Schwartz distributional derivative. This operator is uniquely
defined up to an arbitrary numerical constant. Time derivatives and partial
derivatives with respect to the singular points are also investigated. In the
course of the paper, all the formulas needed in the application to the physical
problem are derived.

</DOC>
<DOC>
<DOCNO> 40167 </DOCNO>
Cross Section for b Jet Production in pbar-p Collisions at sqrt(s) = 1.8


  Bottom quark production in pbar-p collisions at sqrt(s)=1.8 TeV is studied
with 5 inverse picobarns of data collected in 1995 by the DO detector at the
Fermilab Tevatron Collider. The differential production cross section for b
jets in the central rapidity region (|y(b)| < 1) as a function of jet
transverse energy is extracted from a muon-tagged jet sample. Within
experimental and theoretical uncertainties, DO results are found to be higher
than, but compatible with, next-to-leading-order QCD predictions.

</DOC>
<DOC>
<DOCNO> 101640 </DOCNO>
On a filtered multiplicative basis of group algebras


  Let $K$ be a field of characteristic $p$ and $G$ a nonabelian metacyclic
finite $p$-group. We give an explicit list of all metacyclic $p$-groups $G$,
such that the group algebra $KG$ over a field of characteristic $p$ has a
filtered multiplicative $K$-basis. We also present an example of a
non-metacyclic 2-group $G$, such that the group algebra $KG$ over any field of
characteristic 2 has a filtered multiplicative $K$-basis.

</DOC>
<DOC>
<DOCNO> 11216 </DOCNO>
Multispecies reaction-diffusion systems


  Multispecies reaction-diffusion systems, for which the time evolution
equation of correlation functions become a closed set, are considered. A formal
solution for the average densities is found. Some special interactions and the
exact time dependence of the average densities in these cases are also studied.
For the general case, the large time behaviour of the average densities has
also been obtained.

</DOC>
<DOC>
<DOCNO> 8710 </DOCNO>
Recent Theoretical Results for Nonequilibrium Deposition of Submicron


  Selected theoretical developments in modeling of deposition of submicrometer
size (submicron) particles on solid surfaces, with and without surface
diffusion, of interest in colloid, polymer, and certain biological systems, are
surveyed. We review deposition processes involving extended objects, with
jamming and its interplay with in-surface diffusion yielding interesting
dynamics of approach to the large-time state. Mean-field and low-density
approximation schemes can be used in many instances for short and intermediate
times, in large enough dimensions, and for particle sizes larger than few
lattice units. Random sequential adsorption models are appropriate for higher
particle densities (larger times). Added diffusion allows formation of denser
deposits and leads to power-law large-time behavior which, in one dimension
(linear substrate, such as DNA), was related to diffusion-limited reactions,
while in two dimensions (planar substrate), was associated with evolution of
the domain-wall and defect network, reminiscent of equilibrium ordering
processes.

</DOC>
<DOC>
<DOCNO> 99511 </DOCNO>
On finiteness of the number of boundary slopes of immersed surfaces in


  For any hyperbolic 3-manifold $M$ with totally geodesic boundary, there are
finitely many boundary slopes for essential immersed surfaces of a given genus.
There is a uniform bound for the number of such boundary slopes if the genus of
$\partial M$ or the volume of $M$ is bounded above. When the volume is bounded
above, then area of $\partial M$ is bounded above and the length of closed
geodesic on $\partial M$ is bounded below.

</DOC>
<DOC>
<DOCNO> 100015 </DOCNO>
A remark on quiver varieties andweyl groups


  In this paper we define an action of the Weyl group on the quiver varieties
$M_{m,\grl}(d,v)$ with generic $(m,\grl)$. To do it we describe a set of
generators of the projective ring of a quiver variety. We also prove
connectness for the smooth quiver variety $M(d,v)$ and normality for $M_0(d,v)$
in the case of a quiver of finite type and $d-v$ a regular weight.

</DOC>
<DOC>
<DOCNO> 119324 </DOCNO>
Implications of the cosmic infrared background for light production and


  The Cosmic Background due to the integrated radiation from galaxies over the
whole life of the Universe is reviewed. We find that this background is well
constrained by measurements. The total power in the background is in the range
60-93 nW/m2/sr. The data show the existence of a minimum separating the direct
stellar radiation from the infrared part due to radiation reemitted by dust.
This reemitted dust radiation is about 1-2.6 time the background power in the
optical/near-IR thus much larger than the same ratio measured locally (30%).
The far-infrared and submillimeter background is likely to be dominated by
redshifted infrared galaxies. The long wavelength spectrum of the background
being significantly flatter than the spectrum of these galaxies it strongly
constrains the far-infrared radiation production rate history which must
increase by a factor larger than 10 between the present time and a redshift 1
and then stays rather constant at higher redshift, contrary to the ultraviolet
radiation production rate which decreases rapidly.
  Several models of galaxy evolution have been proposed to explain the
submillimeter background. In this paper we do not propose a new model; we
systematically explore the allowed range of evolution histories allowed by the
data. If infrared galaxies are mostly powered by starbursts as indicated by
recent observations, this infrared production history reflects the history of
starbursts in the Universe.

</DOC>
<DOC>
<DOCNO> 85178 </DOCNO>
A Rotating Vacuum and the Quantum Mach's Principle


  In this work we consider a quantum analog of Newton's bucket experiment in a
flat spacetime: we take an Unruh-DeWitt detector in interaction with a real
massless scalar field. We calculate the detector's excitation rate when it is
uniformly rotating around some fixed point and the field is prepared in the
Minkowski vacuum and also when the detector is inertial and the field is in the
Trocheries-Takeno vacuum state. These results are compared and the relations
with a quantum analog of Mach's principle are discussed.

</DOC>
<DOC>
<DOCNO> 67902 </DOCNO>
The use of early data on B --> rho pi decays


  This paper reviews the Dalitz plot analysis for the decays $B^0(\bar B^0) \to
\rho \pi \to \pi^+ \pi^- \pi^0$. We discuss what can be learned about the ten
parameters in this analysis from untagged and from tagged time-integrated data.
We find that, with the important exception of the interesting CP violating
quantity $\alpha$, the parameters can be determined from this data sample --
and, hence, they can be measured at CLEO as well as at the asymmetric $B$
factories. This suggests that the extraction of $\alpha$ from the
time-dependent data sample can be accomplished with a smaller data sample (and,
therefore, sooner) than would be required if all ten parameters were to be
obtained from that time-dependent data sample alone. We also explore bounds on
the shift of the true angle $\alpha$ from the angle measured from charged
$\rho$ final states alone. These may be obtained prior to measurements of the
parameters describing the neutral $\rho$ channel, which are expected to be
small.

</DOC>
<DOC>
<DOCNO> 118513 </DOCNO>
Radiatively inefficient accretion disks


  Radiatively inefficient (or advection dominated) disks are discussed at an
introductory level. Ion supported and radiation supported flows are discussed,
the different consequences of advection dominated flows onto black holes vs.
solid surfaces (neutron stars, white dwarfs), hydrodynamics, the role of the
ratio of specific heats, and the possible connection between ADAFs and
outflows.

</DOC>
<DOC>
<DOCNO> 118738 </DOCNO>
Detection of polarized mm and submm emission from SgrA*


  We report the detection of linear polarization from SgrA* at 750, 850, 1350
and 2000 microns which confirms the contribution of synchrotron radiation. From
the lack of polarization at longer wavelengths it appears to arise in the
millimetre/sub-millimetre excess. There are large position angle changes
between the millimetre and sub-millimetre results and these are discussed in
terms of a polarized dust contribution in the sub-millimetre and various
synchrotron models. In the model which best explains the data the synchrotron
radiation from the excess is self-absorbed in the millimetre region and becomes
optically thin in the sub-millimetre. This implies that the excess arises in an
extremely compact source to the order of 2 Schwarzschild radii.

</DOC>
<DOC>
<DOCNO> 174526 </DOCNO>
Transition from in-plane to out-of-plane azimuthal enhancement in Au+Au


  The incident energy at which the azimuthal distributions in semi-central
heavy ion collisions change from in-plane to out-of-plane enhancement, E_tran,
is studied as a function of mass of emitted particles, their transverse
momentum and centrality for Au+Au collisions. The analysis is performed in a
reference frame rotated with the sidewards flow angle, Theta_flow, relative to
the beam axis. A systematic decrease of E_tran as function of mass of the
reaction products, their transverse momentum and collision centrality is
evidenced. The predictions of a microscopic transport model (IQMD) are compared
with the experimental results.

</DOC>
<DOC>
<DOCNO> 119625 </DOCNO>
On the Kinematic Origin of the Luminosity-Pulse Lag Relationship in


  This paper presents an interpretation based on gamma-ray burst source
kinematics for the relationship found by Norris et al. between peak luminosity
and energy-dependent pulse lag. I argue that the correlation should instead be
between "number" luminosity and pulse lag. This interpretation improves the
least-squares fit of this correlation for the known bursts by 25 percent or
more. It also suggests a distance estimation scheme. I propose that this
relationship is due to the variation in line-of-sight velocity among bursts.
This interpretation allows one to speculate on the range of gamma-ray burst
expansion velocities or the size of their jet opening angles.

</DOC>
<DOC>
<DOCNO> 10860 </DOCNO>
Social Percolation on Inhomogeneous Spanning Network


  The Social Percolation model recently proposed by Solomon et al. is studied
on the Ising correlated inhomogeneous network. The dynamics in this is studied
so as to understand the role of correlations in the social structure. Thus the
possible role of the structural social connectivity is examined.

</DOC>
<DOC>
<DOCNO> 8749 </DOCNO>
High-frequency hopping conductivity in the quantum Hall effect regime:


  The high-frequency conductivity of Si delta-doped GaAs/AlGaAs
heterostructures is studied in the integer quantum Hall effect (QHE) regime,
using acoustic methods. Both the real and the imaginary parts of the complex
conductivity are determined from the experimentally observed magnetic field and
temperature dependences of the velocity and the attenuation of a surface
acoustic wave. It is demonstrated that in the structures studied the mechanism
of low-temperature conductance near the QHE plateau centers is hopping. It is
also shown that at magnetic fields corresponding to filling factors 2 and 4,
the doped Si delta- layer efficiently shunts the conductance in the
two-dimensional electron gas (2DEG) channel. A method to separate the two
contributions to the real part of the conductivity is developed, and the
localization length in the 2DEG channel is estimated.

</DOC>
<DOC>
<DOCNO> 10145 </DOCNO>
Numerical study of disorder effects on the three-dimensional Hubbard


  Combined effects of interactions and disorder are investigated using a finite
temperature quantum Monte Carlo technique for the three-dimensional Hubbard
model with random potentials of a finite range. Temperature dependence of the
charge compressibility shows that the Mott gap collapses beyond a finite
disorder strength. This is a quantum phase transition from an incompressible
phase to a compressible phase driven by disorder. We calculate the
antiferromagnetic structure factor in the presence of disorder as well. Strong
antiferromagnetic correlation, which is characteristic of the Mott insulator,
is destroyed by a finite amount of disorder.

</DOC>
<DOC>
<DOCNO> 116435 </DOCNO>
Deformed Lorentz Symmetry and High-Energy Astrophysics (I)


  An updated discussion of Lorentz symmetry violation in particle physics at
very high energy is presented, focusing on applications of models of deformed
Lorentz symmetry to high-energy astrophysics.

</DOC>
<DOC>
<DOCNO> 170327 </DOCNO>
Hybrid classical-quantum dynamics


  A hybrid formalism is proposed for interacting classical and quantum sytems.
This formalism is mathematically consistent and reduces to standard classical
and quantum mechanics in the case of no interaction. However, in the presence
of interaction, the correspondence principle is violated.

</DOC>
<DOC>
<DOCNO> 120085 </DOCNO>
Metal Enrichment of the Intergalactic Medium at z=3 by Galactic Winds


  Studies of quasar absorption lines reveal that the low density intergalactic
medium at z ~ 3 is enriched to 0.001-0.01 solar metallicity. This enrichment
may have occurred in an early generation of Population III stars at redshift z
>~ 10, by protogalaxies at 6 <~ z <~ 10, or by larger galaxies at 3 <~ z <~ 6.
This paper addresses the third possibility by calculating the enrichment of the
IGM at z >~ 3 by galaxies of baryonic mass >~ 10^8.5 solar masses. We use
already completed cosmological simulations to which we add a prescription for
chemical evolution and metal ejection by winds, assuming that the winds have
properties similar to those observed in local starbursts and Lyman-break
galaxies. Results are given for a number of representative models, and we also
examine the properties of the galaxies responsible for the enrichment as well
as the physical effects responsible for wind escape and propagation. We find
that winds of velocity >~ 200-300 km/s are capable of enriching the IGM to the
mean level observed, though many low-density regions would remain metal free.
Calibrated by observations of Lyman-break galaxies, our calculations suggest
that most galaxies at z >~ 3 should drive winds that can escape and propagate
to large radii. The primary effect limiting the enrichment of low-density IG
gas in our scenario is then the travel time from high- to low-density regions,
implying that the metallicity of low-density gas is a strong function of
redshift.

</DOC>
<DOC>
<DOCNO> 100373 </DOCNO>
Cohomology of Hopf Bimodules and Cup-product


  Given a Hopf algebra A, there exist various cohomology theories for the
category of Hopf bimodules over A, introduced by M. Gerstenhaber and S.D.
Schack, and by C. Ospel. We prove, when A is finite dimensional, that they are
equal to the Ext functor on the module category of an associative algebra
associated to A, described by C. Cibils and M. Rosso. We also give an
expression for a cup-product in the cohomology defined by C. Ospel, and prove
that it corresponds to the Yoneda product of extensions.

</DOC>
<DOC>
<DOCNO> 68405 </DOCNO>
Kaon Photoproduction of the Deuteron and the P-matrix Approach to the YN


  Strangeness photoproduction of the deuteron is investigated theoretically
making use of the covariant reaction formalism and the P-matrix approach the
final state hyperon-nucleon interaction. Remarkably simple analytical
expression for the amplitude is obtained. Pronounced effects due to final state
interaction are predicted.

</DOC>
<DOC>
<DOCNO> 119004 </DOCNO>
Cluster Populations in A115 and A2283


  This paper presents four color narrow-band photometry of clusters A115
($z=0.191$) and A2283 ($z=0.182$) in order to follow the star formation history
of various galaxy types. Although located at similar redshifts, the two
clusters display very different fractions of blue galaxies (i.e. the
Butcher-Oemler effect, $f_B = 0.13$ for A115, $f_B = 0.30$ for A2283). A system
of photometric classification is applied to the cluster members that divides
the cluster population into four classes based on their recent levels of star
formation. It is shown that the blue population of each cluster is primarily
composed of normal starforming (SFR $< 1 M_{\sun}$ yrs$^{-1}$) galaxies at the
high luminosity end, but with an increasing contribution from a dwarf starburst
population below $M_{5500}= -20$. This dwarf starburst population appears to be
the same population of low mass galaxies identified in recent HST imaging (Koo
et al 1997), possible progenitors to present-day cluster dwarf ellipticals,
irregulars and BCD's. Deviations in the color-magnitude relationship for the
red galaxies in each cluster suggest that a population of blue S0's is evolving
into present-day S0 colors at this epoch. The radial distribution of the blue
population supports the prediction of galaxy harassment mechanisms for tidally
induced star formation operating on an infalling set of gas-rich galaxies.

</DOC>
<DOC>
<DOCNO> 69650 </DOCNO>
High Energy Scattering from the $AdS/CFT$ Correspondence


  We apply the AdS/CFT correspondence to derive expressions for the scattering
amplitudes at high energy for gauge theories at strong coupling. A method is
proposed based on the computation of correlators of Wilson loop operators by
their stringy duals in AdS spaces using either the supergravity (weak field) or
classical (minimal surface) approximations.

</DOC>
<DOC>
<DOCNO> 102748 </DOCNO>
Bounded cohomology of subgroups of mapping class groups


  We show that every subgroup of the mapping class group MCG(S) of a compact
surface S is either virtually abelian or it has infinite dimensional second
bounded cohomology. As an application, we give another proof of the
Farb-Kaimanovich-Masur rigidity theorem that states that MCG(S) does not
contain a higher rank lattice as a subgroup.

</DOC>
<DOC>
<DOCNO> 8078 </DOCNO>
Comment to "Emergence of Scaling in Random Networks" (cond-mat/9910332)


  A recent paper "Emergence of scaling in random networks" (cond-mat/9910332)
by Barabasi and Albert proposes a growth mechanism to produce a stationary
scale free distribution of the number of edges per node in large networks such
as the Web. The Barabasi-Albert model predicts that older vertices acquire new
edges at the expense of younger ones, giving a strong correlation between the
time a vertex is introduced and the number of edges it has. We present data
from the Web showing that there is no such correlation and point to an
alternative growth model which produces the correct relationship between the
age of a site and the number of links it has.

</DOC>
<DOC>
<DOCNO> 170421 </DOCNO>
Consistent Histories and the Bohm Approach


  In a recent paper Griffiths claims that the consistent histories
interpretation of quantum mechanics gives rise to results that contradict those
obtained from the Bohm interpretation. This is in spite of the fact that both
claim to provide a realist interpretation of the formalism without the need to
add any new mathematical content and both always produce exactly the same
probability predictions of the outcome of experiments. In constrasting the
differences Griffiths argues that the consistent histories interpretation
provides a more physically reasonable account of quantum phenomena. We examine
this claim and show that the consistent histories approach is not without its
difficulties.

</DOC>
<DOC>
<DOCNO> 68624 </DOCNO>
Time Dependence of Chemical Freeze-out in Relativistic Heavy Ion


  We investigate chemical and thermal freeze-out time dependencies for strange
particle production for CERN SPS heavy ion collisions in the framework of a
dynamical hadronic transport code. We show that the Lambda yield changes
considerably after hadronization in the case of Pb+Pb collisions, whereas for
smaller system sizes (e.g. S+S) the direct particle production dominates over
production from inelastic rescattering. Chemical freeze-out times for strange
baryons in Pb+Pb are smaller than for non-strange baryons, but they are still
sufficiently long for hadronic rescattering to contribute significantly to the
final Lambda yield. Based on inelastic and elastic cross section estimates we
expect the trend of shorter freeze-out times (chemical and kinetic), and thus
less particle production after hadronization, to continue for multi-strange
baryons.

</DOC>
<DOC>
<DOCNO> 9618 </DOCNO>
Zero-temperature d-wave superconducting phase transition


  The Ginzburg-Landau-Wilson theory that describes the disordered Fermi liquid
- d-wave superconductor phase transition at zero temperature is derived at weak
coupling. The theory represents an interacting dissipative system of bosonic
Cooper pairs in an effective random potential. I show that there exists a wide
crossover regime in the theory controlled by a line of Gaussian fixed points,
each of which in two dimensions is characterized by a different universal value
of the dc critical conductivity. Relation to experiments on overdoped and
underdoped cuprates is discussed.

</DOC>
<DOC>
<DOCNO> 9426 </DOCNO>
Comment on ``Local dimer-adatom stacking fault structures from 3x3 to


  Zhao et al. [Phys.Rev.B 58, 13824 (1998)] depicted several atomic structures
of domain boundaries on a Si(111) surface and criticized the article by the
present author and the co-workers. I will point out that their criticism is
incorrect and their structure models have no consistency.

</DOC>
<DOC>
<DOCNO> 39708 </DOCNO>
On the Size of the Dark Side of the Solar Neutrino Parameter Space


  We present an analysis of the MSW neutrino oscillation solutions of the solar
neutrino problem in the framework of two-neutrino mixing in the enlarged
parameter space $(\Delta m^2, \tan^2\theta)$ with $\theta \in
(0,\frac{\pi}{2})$. Recently, it was pointed out that the allowed region of
parameters from a fit to the measured total rates can extend to values $\theta
\geq \frac{\pi}{4}$ (the so called ``dark side'') when higher confidence levels
are allowed. The purpose of this letter is to reanalize the problem including
all the solar neutrino data available, to discuss the dependence on the
statistical criteria in the determination of the CL of the ``dark side'' and to
extract the corresponding limits on the largest mixing allowed by the data. Our
results show that when the Super-Kamiokande data on the zenith angle
distribution of events and the spectrum information is included, the regions
extend more into the dark side.

</DOC>
<DOC>
<DOCNO> 70150 </DOCNO>
Critical exponents of the Gross-Neveu model from the effective average


  The phase transition of the Gross-Neveu model with N fermions is investigated
by means of a non-perturbative evolution equation for the scale dependence of
the effective average action. The critical exponents and scaling amplitudes are
calculated for various values of N in d=3. It is also explicitely verified that
the Neveu-Yukawa model belongs to the same universality class as the
Gross-Neveu model.

</DOC>
<DOC>
<DOCNO> 120143 </DOCNO>
Correlation Function of Galaxy Groups


  We use the Updated Zwicky Catalog of galaxies (Falco et al. 1999) to generate
a catalog of groups, by means of a friend-of-friend algorithm. The correlation
length of the total sample is well fitted with a power law $
\xi(r)=(r/r_0)^\gamma $ with parameters $r_0=9.0 \pm 0.4 h^{-1}Mpc$ and $\gamma
= -1.67 \pm 0.09$ for values of $r<70 h^{-1} Mpc$. Three subsamples defined by
the range of group virial masses ${\cal M}$ were used to have their clustering
properties examined throughout the autocorrelation function. We find an
increase of the amplitude of the correlation function according to the group
masses which extends the results of the $ r_0-d_c$ relation for galaxy systems
at small $d_c$. For completeness we have also analyzed a sample of groups
obtained from the Southern Sky Redshift Survey (da Costa et al.1998) in the
range of virial masses $5\times10^{12}M_{\odot}<{\cal
M}<4\times10^{14}M_{\odot} $ to compare the results with those obtained from
GUZC.

</DOC>
<DOC>
<DOCNO> 123075 </DOCNO>
The Merging History of the Milky Way Disk


  The stellar populations of the stellar halo and of the thick disk of the
Milky Way reveal much about the merging history that our Galaxy, a typical
large disk galaxy, has experienced. Our current understanding, described here,
implies a rather quiet evolution for the disk, back to redshifts of order 2.

</DOC>
<DOC>
<DOCNO> 71483 </DOCNO>
Valence quark distributions in mesons in generalized QCD sum rules


  The method for calculation of valence quark distributions at intermediate $x$
is presented. The imaginary part of the virtual photon forward scattering
amplitude on the quark current with meson quantum number is considered. Initial
and final virtualities $p^2_1$ and $p^2_2$ of the currents are assumed to be
large, negative and different, $p^2_1 \not= p^2_2$. The operator product
expansion (OPE) in $p^2_1, p^2_2$ up to dimension 6 operators is performed.
Double dispersion representations in $p^2_1, p^2_2$ of the amplitude in terms
of physical states contributions are used. Equalling them to those calculated
in QCD by OPE the desired sum rules for quark distributions in mesons are
found. The double Borel transformations are applied to the sum rules, killing
non-diagonal transition terms, which deteriorated the accuracy in the previous
calculations of quark distributions in nucleon. Leading order perturbative
corrections are accounted. Valence quark distributions in pion, longitudinally
and transversally polarized $\rho$-mesons are calculated at intermediate $x$,
$0.2 \la x \la 0.7$ and normalization points $Q^2 = 2-4 GeV^2$ with no fitting
parameters. The use of the Regge behaviour at small $x$ and quark counting
rules at large $x$ allows one to find the first and the second moments of
valence quark distributions. The obtained quark distributions may be used as an
input for evolution equations. In the case of pion the quark distribution is in
agreement with those found from the data on the Drell-Yan process.

</DOC>
<DOC>
<DOCNO> 101366 </DOCNO>
Model selection for inverse problems: Best choice of basis function and


  A complete solution for an inverse problem needs five main steps: choice of
basis functions for discretization, determination of the order of the model,
estimation of the hyperparameters, estimation of the solution, and finally,
caracterisation of the proposed solution. Many works have been done for the
three last steps. The two first have been neglected for a while, in part due to
the complexity of the problem. However, in many inverse problems, particularly
when the number of data is very low, a good choice of the basis functions and a
good selection of the order become primordial. In this paper, we first propose
a complete solution whithin a Bayesian framework. Then, we apply the proposed
method to an inverse elastic electron scattering problem.

</DOC>
<DOC>
<DOCNO> 119360 </DOCNO>
Hard component of ultra-high energy cosmic rays and vortons


  Observed events of ultra-high energy cosmic rays may indicate a hard
component for the energy spectrum of their flux, which might have origin in the
decay of long-lived vortons presumably condensed in the galactic halo. To be
consistent with the needed present density, vortons may have been formed during
the breaking of an abelian symmetry contained in a large GUT group like E6 and
a part of them could have survived the destabilization caused by the
electroweak transition.

</DOC>
<DOC>
<DOCNO> 178488 </DOCNO>
From meson-nucleon scattering to vector mesons in nuclear matter


  We employ meson-nucleon scattering data to deduce the properties of the
low-mass vector mesons in nuclear matter, and present results for the $\rho$
and $\omega$ in-medium spectral functions. The corresponding thermal emission
rate for lepton pairs is also discussed.

</DOC>
<DOC>
<DOCNO> 100171 </DOCNO>
Local formula for the index of a Fourier Integral Operator


  We show that the index of an elliptic Fourier integral operator associated to
a contact diffeomorphism $\phi$ of cosphere bundles of two Riemannian manifolds
X and Y is given by $\int_{B^*X}\hat{A}(T^*X)\exp{\theta} -
\int_{B^*Y}\hat{A}(T^*Y)\exp{\theta}$. Here $B^*$ stands for the unit coball
bundle and $\theta$ is a certain characteristic class depending on the
principal symbol of the Fourier integral operator. In the special case when X=Y
we obtain a different proof of the theorem of Epstein and Melrose.

</DOC>
<DOC>
<DOCNO> 71639 </DOCNO>
Directed Flow of Baryons in Heavy-Ion Collisions


  The collective motion of nucleons from high-energy heavy-ion collisions is
analyzed within a relativistic two-fluid model for different equations of state
(EoS). As function of beam energy the theoretical slope parameter F_y of the
differential directed flow is in good agreement with experimental data, when
calculated for the QCD-consistent EoS described by the statistical mixed-phase
model. Within this model, which takes the deconfinement phase transition into
account, the excitation function of the directed flow <P_x> turns out to be a
smooth function in the whole range from SIS till SPS energies. This function is
close to that for pure hadronic EoS and exhibits no minimum predicted earlier
for a two-phase bag-model EoS. Attention is also called to a possible formation
of nucleon antiflow (F_y < 0) at energies of the order of 100 A GeV.

</DOC>
<DOC>
<DOCNO> 116443 </DOCNO>
Resistive axisymmetric equilibria with arbitrary flow


  An analysis of axisymmetric equilibria with arbitrary incompressible flow and
finite resistivity is presented. It is shown that with large aspect ratio
approximation or vanishing poloidal current, a uniform conductivity profile is
consistent with equilibrium flows. Also a comment made on coexistence of both
toroidal and poloidal flows in an axisymmetric field-reversed configuration.

</DOC>
<DOC>
<DOCNO> 39851 </DOCNO>
Solar Neutrino Rates, Spectrum, and its Moments : an MSW Analysis in the


  We re-examine MSW solutions of the solar neutrino problem in a two flavor
scenario taking (a) the results on total rates and the electron energy spectrum
from the 1117-day SuperKamiokande (SK) data and (b) those on total rates from
the Chlorine and Gallium experiments. We find that the SMA solution gives the
best fit to the total rates data from the different experiments. One new
feature of our analysis is the use of the moments of the SK electron spectrum
in a $\chi^2$ analysis. The best-fit to the moments is broadly in agreement
with that obtained from a direct fit to the spectrum data and prefers a $\Delta
m^2$ comparable to the SMA fit to the rates but the required mixing angle is
larger. In the combined rate and spectrum analysis, apart from varying the
normalization of the $^8$B flux as a free parameter and determining its
best-fit value we also obtain the best-fit parameters when correlations between
the rates and the spectrum data are included and the normalization of the $^8$B
flux held fixed at its SSM value. We observe that the correlations between the
rates and spectrum data are important and the goodness of fit worsens when
these are included. In either case, the best-fit lies in the LMA region.

</DOC>
<DOC>
<DOCNO> 178632 </DOCNO>
Enhanced Event-by-Event Fluctuations in Pion Multiplicity as a Signal of


  The factorial moments of the pion multiplicity distributions are calculated
with HIJING and UrQMD and found to be independent of the pT range included, in
contrast to recent simulations with the linear sigma model which leads to large
enhancements for pions with transverse kinetic energies below 200 MeV. This
supports the use of the ratio of the factorial moments of low and high pT pions
as a signal of ``new'' physics at low momentum scales, such as the formation of
disoriented chiral condensates.

</DOC>
<DOC>
<DOCNO> 99438 </DOCNO>
New Solutions of the Einstein-Dirac Equation in Dimension n=3


  The aim of this short note is to announce the existence of a one-parameter
family of left-invariant metrics on $S^3$ admitting WK-spinors. This family
contains the two non-Einstein Sasakian metrics with WK-spinors on $S^3$, but
does not contain the standard sphere $S^3$ with Killing spinors. Moreover, any
simply-connected, complete Riemannian manifold $X^3 \not= S^3$ with WK-spinors
such that the eigenvalues of the Ricci tensor are constant is isometric to a
space of this one-parameter family.

</DOC>
<DOC>
<DOCNO> 84163 </DOCNO>
Comment on "Metric Fluctuations in Brane Worlds"


  Recently, Ivanov and Volovich (hep-th/9912242) claimed that the perturbation
of $h_{\mu\nu}$ with nonvanishing transverse components $h_{5\mu}$ is not
localized on the brane because $h_{\mu\nu}$ depends on the fifth coordinate $z$
linearly. Consequently, it may indicate that the effective theory is unstable.
However, we point out that such linear dependence on $z$ can be {\it gauged
away}. Hence the solution does not belong to the physical one. Therefore, even
if one includes $h_{5\mu}$, Randall and Sundrum's argument for the localized
gravity on the brane remains correct.

</DOC>
<DOC>
<DOCNO> 122214 </DOCNO>
XMM-Newton observations of the BL Lac MS 0737+7441


  We report on the XMM-Newton observations of the BL Lac object MS 0737.9+7441
during the performance verification phase. A simple power-law fit provides an
adequate description of the integrated spectrum in the 0.2-10 keV energy band.
The photon index is slightly steeper in the EPIC pn data with 2.38+-0.01
compared to the EPIC MOS data (2.28+-0.01). The difference is most probably due
to the present uncertainties in the calibration of the EPIC MOS and EPIC pn
data sets. We report evidence for intrinsic absorption in the distant BL Lac
above the Galactic column N_H,Gal=3.2*10^20 cm^-2 which is N_H,fit(z=0.315)=
(2.70+-0.20)*10^20cm^-2 in the EPIC pn data and N_H,fit(z=0.315)=
(3.25+-0.25)*10^20cm^-2 in the EPIC MOS data assuming neutral gas and solar
abundances. The flux variations are found to be of the order of 10 %.

</DOC>
<DOC>
<DOCNO> 69996 </DOCNO>
Reach of the CERN LHC for the Minimal Anomaly-Mediated SUSY Breaking


  We examine the reach of the CERN LHC pp collider for supersymmetric models
where the dominant contribution to soft SUSY breaking parameters arises from
the superconformal anomaly. In the simplest viable anomaly mediated SUSY
breaking (AMSB) model, tachyonic slepton squared masses are made positive by
adding a universal contribution m_0^2 to all scalars. We use the event
generator ISAJET to generate AMSB signal events as a function of model
parameter space. Assuming an integrated luminosity of 10 fb-1, the LHC can
reach to values of $m_{\tg}\sim 2.3$ TeV for low values of $m_0$, where the
dilepton plus jets plus E_T(missing) channel offers the best reach. For large
$m_0$, the best signature is typically 0 or 1 isolated lepton plus jets plus
E_T(missing); in this case the reach is typically diminished to values of
$m_{\tg}\sim 1.3$ TeV. The presence of terminating tracks in a subset of signal
events could serve to verify the presence of a long lived lightest chargino
which is generic in the minimal AMSB model.

</DOC>
<DOC>
<DOCNO> 10748 </DOCNO>
Bosons and Environment


  The role of background in bosonic quantum statistics is discussed in the
frame of a new approach in terms of coherent states. Bosons are indeed detected
in different physical situations where they exhibit different and apparently
unconnected properties. Besides Bose gas we consider bosons in particle physics
and bosons in harmonic traps. In particle physics bosons are dealt with in a
context where the number of observed particles is finite: here the relevant
features are the canonical commutation relations, which we shall show to be
related to a Boltzmann-like distribution. A further case is Bose condensate in
harmonic traps, where discrete spectrum leads us to predict, below T_c, a new
critical temperature. The unified approach proposed shows that all defferences
can be ascribed to the environment.

</DOC>
<DOC>
<DOCNO> 68151 </DOCNO>
Orbital Angular Momentum Parton Distributions in Light-Front Dynamics


  We study the quark angular momentum distribution in the nucleon within a
light-front covariant quark model. Special emphasis is put into the orbital
angular momentum: a quantity which is very sensitive to the relativistic
treatment of the spin in a light-front dynamical approach. Discrepancies with
the predictions of the low-energy traditional quark models where relativistic
spin effects are neglected, are visible also after perturbative evolution to
higher momentum scales. Orbital angular momentum distributions and their
contribution to the spin sum rule are calculated for different phenomenological
mass operators and compared with the results of the MIT bag model.

</DOC>
<DOC>
<DOCNO> 122579 </DOCNO>
The nature of the bright submillimeter galaxy population: a radio


  Deep submillimetre surveys have successfully detected distant, star-forming
galaxies, enshrouded in vast quantities of dust and which emit most of their
energy at far infrared wavelengths. These luminous galaxies are an important
constituent of the Universal star-formation history, and any complete model of
galaxy evolution must account for their existence. Although these sources have
been tentatively identified with very faint and sometimes very red optical
counterparts, their poorly constrained redshift distribution has made their
interpretation unclear. In particular, it was not understood if these galaxies
had been missed in previous surveys, or if they constituted a truly new class
of objects, undetectable at other wavelengths. By utilizing a radio selection
technique, we have isolated a sample of 20 sub-mm objects representative of the
850 micron population brighter than 5 mJy with z<~3. We show that these
galaxies are so heavily dust obscured that they remain essentially 'invisible'
to ultraviolet selection. Furthermore, relying on the radio-submillimeter flux
density ratio, we estimate their redshift distribution, finding a median of
two. While not a substitute for the thorough followup of blank field sub-mm
surveys, our results do shed light on a substantial portion of the luminous
sub-mm population with z<~3.

</DOC>
<DOC>
<DOCNO> 152324 </DOCNO>
Trieste lectures on solitons in noncommutative gauge theories


  We present a pedagogical introduction into noncommutative gauge theories,
their stringy origin, and non-perturbative effects, including monopole and
instanton solutions

</DOC>
<DOC>
<DOCNO> 121985 </DOCNO>
The Relative Star Formation Histories of Spiral Bulges and Elliptical


  Hierarchical galaxy formation models make specific predictions concerning the
relative assembly rates and star formation histories of spiral bulges and field
ellipticals. Independently of the cosmological model and initial power spectrum
of fluctuations, at all epochs the stellar populations in spiral bulges should
be older and redder than those in typical ellipticals selected at the same
redshift. To test this simple prediction, we analyze the internal optical
colors of a complete sample of I<24 mag early-type and spiral galaxies from the
Northern and Southern Hubble Deep Fields (HDF). The subset of galaxies in the
Northern HDF are also investigated in the near-infrared using NICMOS
photometry. We compare the central (inner 5% radius) colors of those spirals
with clearly visible bulges with the integrated colors of ellipticals in our
sample. Comparisons are possible to a redshift z~1 at which point well-defined
bulges become difficult to locate. While spiral bulges are systematically
redder in their optical colors than their associated disks at all redshifts, we
find that the majority are significantly bluer than the red locus occupied by
most field ellipticals at similar redshifts. In the near-infrared, similar
trends are found at redshifts z<0.6, but at higher redshifts some bulges as red
as the reddest ellipticals are found. We conclude that a significant
rejuvenation may have occurred in the inner stellar populations of many spiral
galaxies at intermediate redshifts.

</DOC>
<DOC>
<DOCNO> 123034 </DOCNO>
The Cannonball Model of Gamma Ray Bursts: Spectral and Temporal


  Recent observations suggest that gamma ray bursts (GRBs) and their afterglows
are produced by highly relativistic jets emitted in supernova explosions. We
have proposed that the result of the event is not just a compact object plus
the ejecta: within days, a fraction of the parent star falls back to produce a
thick accretion disk. The subsequent accretion generates jets and constitutes
the GRB ``engine'', as in the observed ejection of relativistic ``cannonballs''
of plasma by microquasars and active galactic nuclei. Here we investigate the
production of a GRB as the jetted cannonballs exit the supernova shell reheated
by their collision with it, emitting highly forward-collimated radiation. Each
cannonball corresponds to an individual pulse in a GRB. We cannot predict the
timing sequence of these pulses, but the Cannonball Model fares very well in
describing the total energy, energy spectrum, and time-dependence of the
individual pulses.

</DOC>
<DOC>
<DOCNO> 70801 </DOCNO>
Has the QCD RG-Improved Parton Content of Virtual Photons been Observed?


  It is demonstrated that present $e^+e^-$ and DIS ep data on the structure of
the virtual photon can be understood entirely in terms of the standard `naive'
quark--parton model box approach. Thus the QCD renormalization group (RG)
improved parton distributions of virtual photons, in particular their gluonic
component, have not yet been observed. The appropriate kinematical regions for
their future observation are pointed out as well as suitable measurements which
may demonstrate their relevance.

</DOC>
<DOC>
<DOCNO> 13660 </DOCNO>
Fractionalized Phase in an XY-Z_2 Gauge Model


  We study a model with fractional quantum numbers using Monte Carlo
techniques. The model is composed of bosons interacting though a $Z_2$ gauge
field. We find that the system has three phases: a phase in which the bosons
are confined, a fractionalized phase in which the bosons are deconfined, and a
phase in which the bosons are condensed. The deconfined phase has a
``topological'' order due to the degeneracy in the ground state of the gauge
field. We discuss an experimental test proposed by Senthil and Fisher that uses
the topological order to determine the existence of a deconfined,
fractionalized phase.

</DOC>
<DOC>
<DOCNO> 13672 </DOCNO>
Weak localization in disordered systems at the ballistic limit


  The weak localization (WL) contribution to the two-level correlation function
is calculated for two-dimensional disordered conductors. Our analysis extends
to the nondiffusive (ballistic) regime, where the elastic mean path is of order
of the size of the system. In this regime the structure factor (the Fourier
transform of the two-point correlator) exhibits a singular behavior consisting
of dips superimposed on a smooth positive background. The strongest dips appear
at periods of the periodic orbits of the underlying clean system. Somewhat
weaker singularities appear at times which are sums of periods of two such
orbits. The results elucidate various aspects of the weak localization physics
of ballistic chaotic systems.

</DOC>
<DOC>
<DOCNO> 69732 </DOCNO>
DVCS amplitude in the parton model


  We compute amplitude of deeply virtual Compton scattering in the parton
model. We found that the amplitude up to the accuracy O(1/Q) depends on new
skewed parton distributions (SPD's). These additional contributions make the
DVCS amplitude explicitly transverse.

</DOC>
<DOC>
<DOCNO> 85661 </DOCNO>
A New Formation Channel for Double Neutron Stars Without Recycling:


  We report on a new evolutionary path leading to the formation of close double
neutron stars (NS), with the unique characteristic that none of the two NS ever
had the chance to be recycled by accretion. The existence of this channel stems
from the evolution of helium-rich stars (cores of massive NS progenitors),
which has been neglected in most previous studies of double compact object
formation. We find that these non-recycled NS-NS binaries are formed from bare
carbon-oxygen cores in tight orbits, with formation rates comparable to or
maybe even higher than those of recycled NS-NS binaries. On the other hand,
their detection probability as binary pulsars is greatly reduced (by about
1000) relative to recycled pulsars, because of their short lifetimes. We
conclude that, in the context of gravitational-wave detection of NS-NS inspiral
events, this new type of binaries calls for an increase of the rate estimates
derived from the observed NS-NS with recycled pulsars, typically by factors of
1.5-3 or even higher.

</DOC>
<DOC>
<DOCNO> 119171 </DOCNO>
Departures From Axisymmetric Morphology and Dynamics in Spiral Galaxies


  New HI synthesis data have been obtained for six face-on galaxies with the
Very Large Array. These data and reanalyses of three additional data sets make
up a sample of nine face-on galaxies analyzed for deviations from axisymmetry
in morphology and dynamics. This sample represents a subsample of galaxies
already analyzed for morphological symmetry properties in the R-band. Four
quantitative measures of dynamical nonaxisymmetry are compared to one another
and to the quantitative measures of morphological asymmetry in HI and R-band to
investigate the relationships between nonaxisymmetric morphology and dynamics.
We find no significant relationship between asymmetric morphology and most of
the dynamical measures in our sample. A possible relationship is found,
however, between morphology and dynamical position angle differences between
approaching and receding sides of the galaxy.

</DOC>
<DOC>
<DOCNO> 68118 </DOCNO>
Hyperfine effects in charmed baryons


  Hadron masses are calculated in quenched lattice QCD with a fermion action of
the D234 type on an anisotropic lattice. Hyperfine splittings for singly
charmed baryons are found to be in agreement with expectations from the quark
model and with a magnitude slightly larger than experimental values. Masses of
doubly charmed baryons are also calculated and compared to a variety of model
calculations. Hyperfine splittings in doubly charmed baryons are found to be
slightly smaller than in singly charmed states.

</DOC>
<DOC>
<DOCNO> 68759 </DOCNO>
N* Resonances in e+e- Collisions at Bepc


  $J/\Psi$ particles are abundantly produced at the Beijing Electron Positron
Collider (BEPC). The $J/\Psi$ decays provide an excellent place for studying
$N^*$ resonances. For $J/\Psi\to\bar NN\pi$ and $\bar NN\pi\pi$, the $\pi N$
and $\pi\pi N$ systems are limited to be pure isospin 1/2 due to isospin
conservation. This is a big advantage in studying $N^*$ resonances from
$J/\Psi$ decays, compared with $\pi N$ and $\gamma N$ experiments which suffer
difficulty on the isospin decomposition of 1/2 and 3/2. All other $N^*$ decay
channels which are presently under investigation at CEBAF(JLab, USA),
ELSA(Bonn,Germany) and GRAAL(Grenoble, France) with real photon or space-like
virtual photon can also be studied at BEPC complementally with the time-like
virtual photon. The process $J/\Psi\to\bar NN^*$ or $N\bar N^*$ provides a new
way to probe the internal structure of the $N^*$ resonances. The recent results
and outlook of our new $N^*$ program at BEPC are presented.

</DOC>
<DOC>
<DOCNO> 122540 </DOCNO>
A young stellar group associated with HD 199143 (d = 48 pc)


  We present new optical and ultraviolet spectroscopy of the anomalous EUV
emitter HD 199143 (F8V). High resolution spectra in the Halpha and Na I D
wavelength regions show evidence for very rapid (a few hundred km/s) rotation
of the stellar photosphere. Using archive IRAS data we also show that the star
has excess emission above photospheric levels at 12 micron. IUE data of
HD199143 reveal the presence of emission lines of Mg II, C I, C II, C III, C
IV, Si IV, He II and N V and show a large variability, both in the continuum
and line fluxes. We propose that all available data of HD 199143 can be
explained by assuming that is has been spun up by accretion of material from a
close T Tauri like companion, responsible for the emission lines, the
ultraviolet variability and the excess infrared emission. The bursting or
flaring nature of this object, mostly in high energies, could be explained as
episodic mass transfer between the star and its close companion. We show that
HD 199143 and the Li-rich late-type dwarf BD-17 6128 form a physical pair and
suggest that both may be part of a new nearby (48 pc) young (approx. 10^7 yr)
stellar association in Capricornius.

</DOC>
<DOC>
<DOCNO> 68093 </DOCNO>
Fermion Generations from the Higgs Sector


  The generation structure in the quark and lepton spectrum is explained as
originating from the excitation spectrum S_n of SU(2)_W doublet scalar fields,
whose ground state S_1 is the Standard Model Higgs field. There is only one
basic family of SU(2)_W doublet left-handed fermions, nu_L, e_L, u_L, d_L,
whose bound states with S_n manifest themselves as the generations of
left-handed quarks and leptons. Likewise, there is only one basic family of the
right-handed fermions, nu_R, e_R, u_R, d_R, which combine with the gauge
invariant scalar fields G_n to produce the right-handed quarks and leptons of
the second and higher generations. There are only four Yukawa coupling
constants, G_nu, G_e, G_u, and G_d, and all quark and lepton masses are
proportional to them. Suppression of flavor changing neutral currents (GIM
mechanism) is automatic. nu_mu and nu_tau are expected to be massive.

</DOC>
<DOC>
<DOCNO> 121511 </DOCNO>
Southern Hemisphere Observations of a $10^{18}$eV Cosmic Ray Source Near


  We report on an analysis of data from the southern hemisphere SUGAR cosmic
ray detector. We confirm the existence of an excess of $10^{18}$eV cosmic rays
from a direction close to the Galactic Centre, first reported by the AGASA
group. We find that the signal is consistent with that from a point source, and
we find no evidence for an excess of cosmic rays coming from the direction of
the Galactic Centre itself.

</DOC>
<DOC>
<DOCNO> 10408 </DOCNO>
Thermodynamics of a pseudospin-electron model without correlations


  Thermodynamics of a pseudospin-electron model without correlations is
investigated. The correlation functions, the mean values of pseudospin and
particle number, as well as the thermodynamic potential are calculated. The
calculation is performed by a diagrammatic method in the mean field
approximation. Single-particle Green functions are taken in the Hubbard-I
approximation. The numerical research shows that an interaction between the
electron and pseudospin subsystems leads in the $\mu={}$const regime to the
possibility of the first order phase transition at the temperature change with
the jump of the pseudospin mean value $<S^z>$ and reconstruction of the
electron spectrum. In the regime $n={}$const, an instability with respect to
phase separation in the electron subsystem can take place for certain values of
the model parameters.

</DOC>
<DOC>
<DOCNO> 14173 </DOCNO>
Phonon anomalies and electron-phonon interaction in RuSr_2GdCu_2O_8


  Critical behavior of the infrared reflectivity of RuSr_2GdCu_2O_8 ceramics is
observed near the superconducting T_{SC} = 45 K and magnetic T_M = 133 K
transition temperatures. The optical conductivity reveals the typical features
of the c-axis optical conductivity of strongly underdoped multilayer
superconducting cuprates. The transformation of the Cu-O bending mode at 288
cm^{-1} to a broad absorption peak at the temperatures between T^* = 90 K and
T_{SC} is clearly observed, and is accompanied by the suppression of spectral
weight at low frequencies. The correlated shifts to lower frequencies of the
Ru-related phonon mode at 190 cm^{-1} and the mid-IR band at 4800 cm^{-1} on
decreasing temperature below T_M are observed. It provides experimental
evidence in favor of strong electron-phonon coupling of the charge carriers in
the Ru-O layers which critically depends on the Ru core spin alignment. The
underdoped character of the superconductor is explained by strong hole
depletion of the CuO_2 planes caused by the charge carrier self-trapping at the
Ru moments.

</DOC>
<DOC>
<DOCNO> 116843 </DOCNO>
High-Brightness Beams from a Light Source Injector: The Advanced Photon


  The use of existing linacs, and in particular light source injectors, for
free-electron laser (FEL) experiments is becoming more common due to the desire
to test FELs at ever shorter wavelengths. The high-brightness, high-current
beams required by high-gain FELs impose technical specifications that most
existing linacs were not designed to meet. Moreover, the need for specialized
diagnostics, especially shot-to-shot data acquisition, demands substantial
modification and upgrade of conventional linacs. Improvements have been made to
the Advanced Photon Source (APS) injector linac in order to produce and
characterize high-brightness beams. Specifically, effort has been directed at
generating beams suitable for use in the low-energy undulator test line (LEUTL)
FEL in support of fourth-generation light source research. The enhancements to
the linac technical and diagnostic capabilities that allowed for self-amplified
spontaneous emission (SASE) operation of the FEL at 530 nm are described.
Recent results, including details on technical systems improvements and
electron beam measurement techniques, will be discussed. The linac is capable
of accelerating beams to over 650 MeV. The nominal FEL beam parameters used are
as follows: 217 MeV energy; 0.1-0.2% rms energy spread; 4-8 um normalized rms
emittance; 80-120 A peak current from a 0.2-0.7 nC charge at a 2-7 ps FWHM
bunch.

</DOC>
<DOC>
<DOCNO> 85594 </DOCNO>
The 3D Grazing Collision of Two Black Holes


  We present results for two colliding black holes (BHs), with angular
momentum, spin, and unequal mass. For the first time gravitational waveforms
are computed for a grazing collision from a full 3D numerical evolution. The
collision can be followed through the merger to form a single BH, and through
part of the ringdown period of the final BH. The apparent horizon is tracked
and studied, and physical parameters, such as the mass of the final BH, are
computed. The total energy radiated in gravitational waves is shown to be
consistent with the total mass of the spacetime and the final BH mass. The
implication of these simulations for gravitational wave astronomy is discussed.

</DOC>
<DOC>
<DOCNO> 69423 </DOCNO>
Helicity in diffractive vector-meson production


  We study the helicity amplitudes describing the quasielastic production of
vector mesons in deep inelastic scattering within the context of the model
which we previously introduced to describe the ratio of longitudinal to
transverse cross sections. We calculate here a full set of spin flip (and
non-flip) amplitudes and naturally find a significant violation of s-channel
helicity conservation. We present predictions for the 15 spin-density matrix
elements which completely define the angular distributions and the helicity
properties of the produced meson.

</DOC>
<DOC>
<DOCNO> 13625 </DOCNO>
Teleportation of general finite dimensional quantum systems


  Teleportation of finite dimensional quantum states by a non-local entangled
state is studied. For a generally given entangled state, an explicit equation
that governs the teleportation is presented. Detailed examples and the roles
played by the dimensions of the Hilbert spaces related to the sender, receiver
and the auxiliary space are discussed.

</DOC>
<DOC>
<DOCNO> 118648 </DOCNO>
Magellanic-Cloud-Type Interstellar Dust Along Low Density Sightlines in


  We have studied the UV extinction properties along 30 Galactic sightlines
using data from the International Ultraviolet Explorer (IUE) archive that have
never been previously examined. These distant (d > 1 kpc) sightlines were
selected to investigate the distribution and physical conditions of gas located
in low density regions of the Galactic disk and halo. The average densities
along these sightlines are extremely low. It is likely that they are dominated
by the warm intercloud medium and have little contribution from the cold cloud
medium. We find that a subsample of these sightlines has extinction curves with
weak bumps and very steep far-UV extinction reminiscent of the Magellanic
clouds. These sightlines all lie in the region bounded by 325 < l < 0 and -5 >
b > -11. The gas along these sightlines shows forbidden velocities which may
indicate that the dust has been subject to shocks. This type of low density
sightline may mimic the environments found in the Magellanic Clouds. Large
values of N(Ca II)/N(Na I) indicating low depletion are associated with steep
far-UV extinction. A possible correlation exists between decreasing bump
strength and increasing far-UV steepness for extinction curves in the Galaxy
and the Magellanic Clouds.

</DOC>
<DOC>
<DOCNO> 70148 </DOCNO>
Anomalous magnetic moment of a bound electron


  We study binding corrections to the gyromagnetic factor g_e of an electron in
hydrogen-like ions. We argue that the leading order binding effects in
radiative corrections Delta g_rad are universal to all orders in alpha/pi and
the complete result reads Delta g_rad = (g_free - 2) [1+(Z alpha)^2/6] +
O[alpha/pi (Zalpha)^4]. The theoretical uncertainty in the prediction for the
experimentally interesting carbon ion is decreased by a factor of about 3.

</DOC>
<DOC>
<DOCNO> 83085 </DOCNO>
Biologically Motivated Distributed Designs for Adaptive Knowledge


  We discuss how distributed designs that draw from biological network
metaphors can largely improve the current state of information retrieval and
knowledge management of distributed information systems. In particular, two
adaptive recommendation systems named TalkMine and @ApWeb are discussed in more
detail. TalkMine operates at the semantic level of keywords. It leads different
databases to learn new and adapt existing keywords to the categories recognized
by its communities of users using distributed algorithms. @ApWeb operates at
the structural level of information resources, namely citation or hyperlink
structure. It relies on collective behavior to adapt such structure to the
expectations of users. TalkMine and @ApWeb are currently being implemented for
the research library of the Los Alamos National Laboratory under the Active
Recommendation Project. Together they define a biologically motivated
information retrieval system, recommending simultaneously at the level of user
knowledge categories expressed in keywords, and at the level of individual
documents and their associations to other documents. Rather than passive
information retrieval, with this system, users obtain an active, evolving
interaction with information resources.

</DOC>
<DOC>
<DOCNO> 117431 </DOCNO>
The variability of the Seyfert galaxy NGC 2992: the case for a revived


  We report the transition to an active state of the nucleus in the Seyfert 1.9
galaxy NGC 2992, discovered by means of new hard X-ray data. While the 2-10 keV
flux declined by a factor of ~ 20 from 1978 to 1994, two recent BeppoSAX
observations in 1997 and in 1998 caught the nuclear emission raising back to
the same level of activity observed in 1978.
  In both BeppoSAX observations the X-ray spectrum of the source is well
represented by a power law with spectral index Gamma ~ 1.7, absorbed by a
column density of N_H ~ 10^{22} cm^{-2} and characterized by a prominent iron
K\alpha line. While in the second BeppoSAX data set the line properties appear
to be consistent with those expected from accretion disc models, in the first
BeppoSAX data set the iron feature is rather peculiar. The broadening is not
significant and the line energy is E_{K\alpha}=6.62 +/- 0.07 keV, indicating
emission from highly ionized iron. The line has too high equivalent width (~
700 eV) to be produced by a hot scattering medium. By comparing these data with
data previously in the literature, we interpret the spectral and flux changes
in terms of different phases of rebuilding an accretion disc. The timescale for
the disc rebuilding is estimated to range between 1 and 5 years.
  The X-ray data are complemented with optical and near-infrared followup
spectra taken 1.5 months after the discovery of the X-ray burst. The spectra
are characterized by prominent broad emission lines. There is also evidence for
hot dust emission in the H and K bands that, however, is probably still in the
process of increasing.

</DOC>
<DOC>
<DOCNO> 122233 </DOCNO>
Dust in active nuclei. I. Evidence for "anomalous" properties


  We present observational evidences that dust in the circumnuclear region of
AGNs has different properties than in the Galactic diffuse interstellar medium.
By comparing the reddening of optical and infrared broad lines and the X-ray
absorbing column density we find that the E(B-V)/N_H ratio is nearly always
lower than Galactic by a factor ranging from ~3 up to ~100. Other observational
results indicate that the Av/N_H ratio is significantly lower than Galactic in
various classes of AGNs including intermediate type 1.8-1.9 Seyferts, hard
X-ray selected and radio selected quasars, broad absorption line QSOs and grism
selected QSOs. The lack of prominent absorption features at 9.7um (silicates)
and at 2175A (carbon dip) in the spectra of Seyfert 2s and of reddened Seyfert
1s, respectively, add further evidence for dust in the circumnuclear region of
AGNs being different from Galactic.
  These observational results indicate that the dust composition in the
circumnuclear region of AGNs could be dominated by large grains, which make the
extinction curve flatter, featureless and are responsible for the reduction of
the E(B-V)/N_H and Av/N_H ratios.
  Regardless of the physical origin of these phenomena, the reduced dust
absorption with respect to what expected from the gaseous column density should
warn about a mismatch between the optical and the X-ray classification of the
active galactic nuclei in terms of their obscuration.

</DOC>
<DOC>
<DOCNO> 68649 </DOCNO>
Gluino Condensation in an Interacting Instanton Ensemble


  We perform a semi-classical study of chiral symmetry breaking and of the
spectrum of the Dirac operator in QCD with adjoint fermions. For this purpose
we calculate matrix elements of the adjoint Dirac operator between instanton
zero modes and study their symmetry properties. We present simulations of the
instanton ensemble for different numbers of Majorana fermions in the adjoint
representation. These simulations provide evidence that instantons lead to
gluino condensation in supersymmetric gluodynamics.

</DOC>
<DOC>
<DOCNO> 13918 </DOCNO>
Effective temperature of an aging powder


  The aging dynamics and the fluctuation-dissipation relation between the
spontaneous diffusion induced by a random noise and the drift motion induced by
a small stirring force are numerically investigated in a 3D schematic model of
compacting powder: a gravity-driven lattice-gas with kinetic constraints. The
compaction dynamics is characterized by a super-aging behaviour and, in analogy
with glasses, exhibits a purely dynamical time-scale dependent effective
temperature. A simple experiment to measure this quantity is suggested.

</DOC>
<DOC>
<DOCNO> 84532 </DOCNO>
Quantum creation of an Inhomogeneous universe


  In this paper we study a class of inhomogeneous cosmological models which is
a modified version of what is usually called the Lema\^itre-Tolman model. We
assume that we have a space with 2-dimensional locally homogeneous spacelike
surfaces. In addition we assume they are compact. Classically we investigate
both homogeneous and inhomogeneous spacetimes which this model describe. For
instance one is a quotient of the AdS$_4$ space which resembles the BTZ black
hole in AdS$_3$.
  Due to the complexity of the model we indicate a simpler model which can be
quantized easily. This model still has the feature that it is in general
inhomogeneous. How this model could describe a spontaneous creation of a
universe through a tunneling event is emphasized.

</DOC>
<DOC>
<DOCNO> 83409 </DOCNO>
An Approach to the Implementation of Overlapping Rules in Standard ML


  We describe an approach to programming rule-based systems in Standard ML,
with a focus on so-called overlapping rules, that is rules that can still be
active when other rules are fired. Such rules are useful when implementing
rule-based reactive systems, and to that effect we show a simple implementation
of Loyall's Active Behavior Trees, used to control goal-directed agents in the
Oz virtual environment. We discuss an implementation of our framework using a
reactive library geared towards implementing those kind of systems.

</DOC>
<DOC>
<DOCNO> 178485 </DOCNO>
Cluster states in nuclei as representations of a U(n+1) group


  We propose a description of cluster states in nuclei in terms of
representations of unitary algebras U(n+1), where n is the number of space
degrees of freedom. Within this framework, a variety of situations including
both vibrational and rotational spectra, soft and rigid configurations,
identical and non-identical constituents can be described. As an example, we
show how the method can be used to study alpha-clustering configurations in 12C
with point group symmetry D(3h).

</DOC>
<DOC>
<DOCNO> 102112 </DOCNO>
Averaging Principle for Quasi-Geostrophic Motions under Rapidly


  In this paper, the averaging principle for quasi-geostrophic motions with
rapidly oscillating forcing is proved, both on finite but large time intervals
and on the entire time axis. This includes comparison estimate, stability
estimate, and convergence result between quasi-geostrophic motions and its
averaged motions. Furthermore, the existence of almost periodic
quasi-geostrophic motions and attractor convergence are also investigated.

</DOC>
<DOC>
<DOCNO> 12966 </DOCNO>
The Exact Solution of 1-D SU(n) Hubbard model


  In this paper we derive out the exact solution of the SU(n) Hubbard model
through the coordinate and the algebraic Bethe ansatz methods. The energy
spectrum and the Bethe ansatz equations are obtained. Furthermore, we analysis
the ground state and give out the exact analytic solution of the model.

</DOC>
<DOC>
<DOCNO> 170126 </DOCNO>
Error-free optical quantum communication


  An optical scheme for the reliable transfer of quantum information through a
noisy quantum channel is proposed. The scheme is inspired by quantum
error-correction protocols, but it avoids the currently infeasible requirement
for a controlled-NOT operation between single photons. The quantum
communication scheme presented here rejects single bit-flip errors instead of
correcting them and combines quantum-measurement properties of three-particle
entangled (GHZ) states with properties of quantum teleportation.

</DOC>
<DOC>
<DOCNO> 99494 </DOCNO>
A modular functor which is universal for quantum computation


  We show that the topological modular functor from Witten-Chern-Simons theory
is universal for quantum computation in the sense a quantum circuit computation
can be efficiently approximated by an intertwining action of a braid on the
functor's state space. A computational model based on Chern-Simons theory at a
fifth root of unity is defined and shown to be polynomially equivalent to the
quantum circuit model. The chief technical advance: the density of the
irreducible sectors of the Jones representation, have topological implications
which will be considered elsewhere.

</DOC>
<DOC>
<DOCNO> 13517 </DOCNO>
Spin Fluctuation and Persistent Current in a Mesoscopic Ring Coupled to


  We investigate the persistent current influenced by the spin fluctuations in
a mesoscopic ring weakly coupled to a quantum dot. It is shown that the Kondo
effect gives rise to some unusual features of the persistent current in the
limit where the charge transfer between two subsystems is suppressed. Various
aspects of the crossover from a delocalized to a localized dot limit are
discussed in relation with the effect of the coherent response of the Kondo
cloud to the Aharonov-Bohm flux.

</DOC>
<DOC>
<DOCNO> 152312 </DOCNO>
Asymptotic expansion coefficients of the heat kernel in Riemann-Cartan


  By applying the covariant Taylor expansion method, the fifth lower
coefficients the asymptotic expansion of the heat kernel associated with a
fermion of spin 1/2 in Riemann-Cartan space are manifestly given. These
coefficients in Riemann-Cartan space is derived from those obtained in
Riemannian space by simple replacements.

</DOC>
<DOC>
<DOCNO> 119312 </DOCNO>
Searches for Quasars at z > 5


  Quasars continue to be the most luminous objects known in the universe but
are now rivaled by galaxies for having the largest redshifts. I review current
techniques for finding quasars at z > 5 and the status of current optical
surveys. I compare the spectra of known quasars with z \approx 5 with the
spectra of some recently discovered galaxies with z > 5 to see what we may
expect in the future from surveys for high redshift quasars and galaxies. The
prominent emission lines of quasars should make them easier to detect and
confirm spectroscopically than the z > 5 galaxies discovered so far. An update
section to May, 2000 discusses new discoveries made after the meeting.

</DOC>
<DOC>
<DOCNO> 170261 </DOCNO>
Exactly solvable models of quantum mechanics including fluctuations in


  The problem of quantum harmonic oscillator with "regular+random" square
frequency, subjected to "regular+random external force, is considered in
framework of representation of the wave function by complex-valued random
process. Average transition probabilities are calculated. Stochastic density
matrix method is developed, which is used for investigation of thermodinamical
characteristics of the system, such as entropy and average energy.

</DOC>
<DOC>
<DOCNO> 116778 </DOCNO>
Asymmetric Collision of Concepts: Why Eigenstates Alone are Not Enough


  The symmetry of the problem of the apparent deficit in upward-going
atmospheric muon neutrinos reveals two possible, nonexclusive kinds of
solution: Nonlinearity in distance or nonlinearity in angle of observation.
 Nonlinearity in distance leads to the most popular theory for the atmospheric
problem, neutrino flavor oscillations. If the observed deficit is caused by
oscillations and not, say, flavor-changing or other weak-force scattering,
neutrinos must be massive. But, if flavor oscillations occur in vacuum, all
oscillating neutrinos must have exactly equal mass. Theories of oscillation in
matter such as the Mikheyev-Smirnov-Wolfenstein (MSW) effect do not work in
vacuum. This is the conceptual conflict of kinematics versus vacuum
oscillations. Flavor-changing oscillations like those of the
Cabibbo-Kobayashi-Maskawa (CKM) quark theory become possible in vacuum if
freely propagating neutrinos may be associated with local substructure.
 Nonlinearity in angle of observation leads to a simple prediction of an excess
of horizontal muon flavor. This and other angle-based effects should be
observable at Super-Kamiokande or other instruments which can measure
atmospheric flux by flavor.

</DOC>
<DOC>
<DOCNO> 69632 </DOCNO>
The interplay between Weak and Strong Phases and Direct CP Violation


  We present a general analysis on charmless B-meson decays $B\to \pi\pi$ and
$\pi K$. It is noticed that the final state interactions and inelastic
rescattering effects must be significant in order to understand the consistency
of the current data. By using general isospin decompositions, the isospin
amplitudes and the corresponding strong phases could be extracted from a global
$\chi^2$ fit of the experimental data. We emphasize that in general there are
two, rather than one, relative strong phases in the decomposition. In the
assumption of two equalstrong phases as considered in the literature, the
current data, especially the ones concerning $B\to \pi^0 K^{0(\pm)}$decays,
will imply a large isospin amplitude $|a^c_{3/2}| > 40 $, which is larger by a
factor of five than the one from the naive factorization estimation. When two
different strong phases are considered, all the isospin amplitudes can become,
within the $1\sigma$-level, comparable with the theoretical values. We also
show that the difference between the two strong phases cannot be too large and
will be restricted by the most recent upper bound of $B\to \pi^0\pi^0$ decay.
In any case, the strong phases are found to be large and the branching ratio of
$B\to \pi^0\pi^0$ is likely to be enhanced by an order of magnitude in
comparison with the one obtained from the naive factorization approach. Direct
CP violations in all decay modes are also calculated and found to be close to
the sensitivity of the present experiments.

</DOC>
<DOC>
<DOCNO> 151948 </DOCNO>
Discrete Symmetries of Functional Determinants


  We study discrete (duality) symmetries of functional determinants. An exact
transformation of the effective action under the inversion of background fields
$\beta (x) \to \beta^{-1}(x)$ is found. We show that in many cases this
inversion does not change functional determinants. Explicitly studied models
include a matrix theory in two dimensions, the dilaton-Maxwell theory in four
dimensions on manifolds without a boundary, and a two-dimensional dilaton
theory on manifolds with boundaries. Our results provide an exact relation
between strong and weak coupling regimes with possible applications to string
theory, black hole physics and dimensionally reduced models.

</DOC>
<DOC>
<DOCNO> 99504 </DOCNO>
Noncommutative Instantons and Twistor Transform


  Recently N.Nekrasov and A.Schwarz proposed a modification of the ADHM
construction of instantons which produces instantons on a noncommutative
deformation of the 4-dimensional real affine space. In this paper we study the
relation between their construction and algebraic bundles on noncommutative
projective spaces. We exhibit one-to-one correspondences between three classes
of objects: framed bundles on a noncommutative projective plane, certain
complexes of sheaves on a noncommutative 3-dimensional projective space, and
the modified ADHM data. The modified ADHM construction itself is interpreted in
terms of a noncommutative version of the twistor transform. We also prove that
the moduli space of framed bundles on the noncommutative projective plane has a
natural hyperkahler metric and is isomorphic as a hyperkahler manifold to the
moduli space of framed torsion free sheaves on the commutative projective
plane. The natural complex structures on the two moduli spaces do not coincide
but are related by an SO(3) rotation. Finally, we propose a construction of
instantons on a more general noncommutative R^4 than the one considered by
Nekrasov and Schwarz (a q-deformed R^4).

</DOC>
<DOC>
<DOCNO> 68575 </DOCNO>
Lepton pair production by high-energy neutrino in an external


  The process of the lepton pair production by a neutrino propagating in an
external electromagnetic field is investigated in the framework of the Standard
Model. Relatively simple exact expression for the probability as the single
integral is obtained, which is suitable for a quantitative analysis.

</DOC>
<DOC>
<DOCNO> 119692 </DOCNO>
Observational Implications of Precessing Protostellar Discs and Jets


  We consider the dynamics of a protostellar disc in a binary system where the
disc is misaligned with the orbital plane of the binary, with the aim of
determining the observational consequences for such systems. The disc wobbles
with a period approximately equal to half the binary's orbital period and
precesses on a longer timescale. We determine the characteristic timescale for
realignment of the disc with the orbital plane due to dissipation. If the
dissipation is determined by a simple isotropic viscosity then we find, in line
with previous studies, that the alignment timescale is of order the viscous
evolution timescale. However, for typical protostellar disc parameters, if the
disc tilt exceeds the opening angle of the disc, then tidally induced shearing
within the disc is transonic. In general, hydrodynamic instabilities associated
with the internally driven shear result in extra dissipation which is expected
to drastically reduce the alignment timescale. For large disc tilts the
alignment timescale is then comparable to the precession timescale, while for
smaller tilt angles $\delta$, the alignment timescale varies as $(\sin
\delta)^{-1}$. We discuss the consequences of the wobbling, precession and
rapid realignment for observations of protostellar jets and the implications
for binary star formation mechanisms.

</DOC>
<DOC>
<DOCNO> 117249 </DOCNO>
How Much Energy Have Real Fields Time and Space in Multifractal


  On the base of multifractal theory of time and space (see
\cite{kob1}-\cite{kob16}) in this paper shown presence in every space and time
volumes of real space and time fields a huge supply of energy . In the
multifractal Universe every space volume or time interval possesses by huge
amount of energy($\sim10^{60}cm^{3}$) and we discuss the problem is it possible
this new for mankind sorts of energy to extract. 
  Contents: 1. Introduction 2. What are Energy Densities of Real Space and Time
Fields in Multifractal Universe? 3. How Much Energy Space and Time Continually
Lose?

</DOC>
<DOC>
<DOCNO> 99266 </DOCNO>
Modular symbols and Hecke operators


  We survey techniques to compute the action of the Hecke operators on the
cohomology of arithmetic groups. These techniques can be seen as
generalizations in different directions of the classical modular symbol
algorithm, due to Manin and Ash-Rudolph. Most of the work is contained in
papers of the author and the author with Mark McConnell. Some results are
unpublished work of Mark McConnell and Robert MacPherson.

</DOC>
<DOC>
<DOCNO> 151278 </DOCNO>
OM Theory in Diverse Dimensions


  Open string theories can be decoupled from closed strings and gravity by
scaling to the critical electric field. We propose dual descriptions for the
strong coupling limit of these NCOS (Non-Commutative Open String) theories in
six or fewer spacetime dimensions. In particular, we conjecture that the
five-dimensionsal NCOS theory at strong coupling, is a theory of light Open
Membranes (OM), decoupled from gravity, on an M5-brane with a near-critical
three-form field strength. The relation of OM theory to NCOS theories resembles
that of M theory to Type II closed string theories. In two dimensions we
conjecture that supersymmetric U($n$) gauge theory with a unit of electric flux
is dual to the NCOS theory with string coupling $1 \over n$. A construction
based on NS5-branes leads to new theories in six dimensions generalising the
little string theory. A web of dualities relates all the above theories when
they are compactified on tori.

</DOC>
<DOC>
<DOCNO> 70584 </DOCNO>
Direct J/Psi hadroproduction in k_\perp-factorization and the color


  The hadroproduction of direct J/Psi in the framework of the
k_\perp-factorization approach is studied. The color-singlet contribution is
essentially larger than in the collinear approach but is still an order of
magnitude below the data. The deficit may be well described by the color octet
contribution with the value of the matrix element <0|O^{J/\Psi}_8(^3S_1)|0>
substantially decreased in comparison with the fits in the collinear
factorization. This should lead to a reduction of the large transverse
polarization, predicted in the collinear approach.

</DOC>
<DOC>
<DOCNO> 68162 </DOCNO>
Dispersion Laws for Goldstone Bosons in a Color Superconductor


  The effective action for Goldstone bosons in the color-flavor locking phase
of dense QCD is analyzed. Interaction terms and higher derivatives in the
effective action appear to be controlled by different scales. At energies of
order of the superconducting gap, the derivative expansion breaks down, while
interactions still remain suppressed. The effective action valid at energies
and momenta comparable to the gap is derived. Dispersion laws following from
this action are such that the energy of Goldstone bosons is always smaller than
the gap in the quasiparticle spectrum, and Goldstone bosons always propagate
without damping.

</DOC>
<DOC>
<DOCNO> 119213 </DOCNO>
Smoothed Particle Hydrodynamics Simulations of Apsidal and Nodal


  In recent years a handful of systems have been observed to show "negative"
(nodal) superhumps, with periods slightly shorter than the orbital period. It
has been suggested that these modes are a consequence of the slow retrograde
precession of the line of nodes in a disk tilted with respect to the orbital
plane. Our simulations confirm and refine this model: they suggest a roughly
axisymmetric, retrogradely-precessing, tilted disk that is driven at a period
slightly less than half the orbital period as the tidal field of the orbiting
secondary encounters in turn the two halves of the disk above and below the
midplane. Each of these passings leads to viscous dissipation on one face of an
optically-thick disk -- observers on opposite sides of the disk would each
observe one brightening per orbit, but 180 degrees out of phase with each
other.

</DOC>
<DOC>
<DOCNO> 101444 </DOCNO>
Ribbon Operators and Hall-Littlewood Symmetric Functions


  Given a partition $\la = (\la_1, \la_2, ... \la_k)$, let $\la^{rc} =
(\la_2-1, \la_3-1, ... \la_k-1)$. It is easily seen that the diagram $\la\slash
\la^{rc}$ is connected and has no $2 \times 2$ subdiagrams which we shall refer
to as a ribbon. To each ribbon $R$, we associate a symmetric function operator
$S^R$. We may define the major index of a ribbon $maj(R)$ to be the major index
of any permutation that fits the ribbon. This paper is concerned with the
operator $H_{1^k}^q = \sum_R q^{maj(R)} S^R$ where the sum is over all
$2^{k-1}$ ribbons of size $k$. We show here that $H_{1^k}^q$ has truly
remarkable properties, in particular that it is a Rodriguez operator that adds
a column to the Hall-Littlewood symmetric functions. We believe that some of
the tools we introduce here to prove our results should also be of independent
interest and may be useful to establish further symmetric function identities.

</DOC>
<DOC>
<DOCNO> 123268 </DOCNO>
Cosmological Parameters and Hyper-Parameters: The Hubble Constant from


  We generalise the procedure for joint estimation of cosmological parameters
to allow freedom in the relative weights of various probes. This is done by
including in the joint Likelihood function a set of 'Hyper-Parameters', which
are dealt with using Bayesian considerations. The resulting algorithm is simple
to implement. We illustrate the method by estimating the Hubble constant H_0
from the recent Cosmic Microwave Background experiments Boomerang and Maxima.
For an assumed flat Lambda-CDM model with fixed parameters (n=1, Omega_m =
1-lambda = 0.3, Omega_b h^2 = 0.03, Qrms = 18 mu K) we solve for a single
parameter, H_0= 79 +- 4 km/sec/Mpc (95 % CL, random errors only), slightly
higher but still consistent with recent results from Cepheids. We discuss how
the 'Hyper-Parameters' approach can be generalised for a combination of cosmic
probes, and for other priors on the Hyper-Parameters.

</DOC>
<DOC>
<DOCNO> 170335 </DOCNO>
Phase diffusion as a model for coherent suppression of tunneling in the


  We study the stabilization of coherent suppression of tunneling in a driven
double-well system subject to random periodic $\delta-$function ``kicks''. We
model dissipation due to this stochastic process as a phase diffusion process
for an effective two-level system and derive a corresponding set of Bloch
equations with phase damping terms that agree with the periodically kicked
system at discrete times. We demonstrate that the ability of noise to localize
the system on either side of the double-well potenital arises from overdamping
of the phase of oscillation and not from any cooperative effect between the
noise and the driving field. The model is investigated with a square wave
drive, which has qualitatively similar features to the widely studied
cosinusoidal drive, but has the additional advantage of allowing one to derive
exact analytic expressions.

</DOC>
<DOC>
<DOCNO> 83195 </DOCNO>
Looking at discourse in a corpus: The role of lexical cohesion


  This paper is aimed at reporting on the development and application of a
computer model for discourse analysis through segmentation. Segmentation refers
to the principled division of texts into contiguous constituents. Other studies
have looked at the application of a number of models to the analysis of
discourse by computer. The segmentation procedure developed for the present
investigation is called LSM ('Link Set Median'). It was applied to three corpus
of 300 texts from three different genres. The results obtained by application
of the LSM procedure on the corpus were then compared to segmentation carried
out at random. Statistical analyses suggested that LSM significantly
outperformed random segmentation, thus indicating that the segmentation was
meaningful.

</DOC>
<DOC>
<DOCNO> 170510 </DOCNO>
Beyond Stabilizer Codes II: Clifford Codes


  Knill introduced a generalization of stabilizer codes, in this note called
Clifford codes. It remained unclear whether or not Clifford codes can be
superior to stabilizer codes. We show that Clifford codes are stabilizer codes
provided that the abstract error group has an abelian index group. In
particular, if the errors are modelled by tensor products of Pauli matrices,
then the associated Clifford codes are necessarily stabilizer codes.

</DOC>
<DOC>
<DOCNO> 101078 </DOCNO>
Some applications of localization to enumerative problems


  A simple corollary of the localization theorem (due to the author and,
independently, to Lian-Liu-Yau) is applied to several problems in enumerative
geometry. New formulas for Schubert calculus on flag manifolds, due to Kong,
and a new reconstruction theorem for genus-zero Gromov-Witten invariants, due
to Bertram-Kley, are discussed, as well as some simple functorial properties of
Givental's J-function. This paper will appear in the issue of the Michigan
Mathematical Journal dedicated to Bill Fulton.

</DOC>
<DOC>
<DOCNO> 10516 </DOCNO>
Thermal operators and cluster topology in q-state Potts Model


  We discuss a new class of identities between correlation functions which
arise from a local Z_2 invariance of the partition function of the q-state
Potts model on general graphs or lattices. Their common feature is to relate
the thermal operators of the Potts model to some topological properties of the
Fortuin-Kasteleyn clusters. In particular it turns out that any even
correlation function can be expressed in terms of observables which probe the
linking properties of these clusters. This generalises a class of analogous
relations recently found in the Ising model.

</DOC>
<DOC>
<DOCNO> 170461 </DOCNO>
Coherent Phenomena in Photonic Crystals


  We study the spontaneous emission, the absorption and dispersion properties
of a ${\bf \Lambda}$-type atom where one transition interacts near resonantly
with a double-band photonic crystal. Assuming an isotropic dispersion relation
near the band edges, we show that two distinct coherent phenomena can occur.
First, the spontaneous emission spectrum of the adjacent free space transition
obtains `dark lines' (zeroes in the spectrum). Second, the atom can become
transparent to a probe laser field coupling to the adjacent free space
transition.

</DOC>
<DOC>
<DOCNO> 122257 </DOCNO>
A Massive Dark Object in the S0 galaxy NGC 4350


  We present a new detection of a Massive Dark Object in the S0 Galaxy NGC
4350, obtained applying a new dynamical model on ground-based photometric and
kinematic data already present in literature.

</DOC>
<DOC>
<DOCNO> 84586 </DOCNO>
Misner-brane cosmology


  A brane universe derived from the Randall-Sundrum models is considered in
which an additional Misner-like periodicity is introduced in the extra
direction. This model solves the ambiguity in the choice of the brane world by
identifying the branes with opposite tensions, in such a way that if one enters
the brane with positive tension, one finds oneself emerging from the brane with
negative tension, without having experienced any tension. We show that the
cosmological evolution resulting from this model matches that of the standard
Friedmann scenario, at least in the radiation dominated era, and that there
exist closed timelike curves only in the bulk, but not in the branes which are
chronologically protected from causality violations by quantum-mechanically
stable chronology horizons.

</DOC>
<DOC>
<DOCNO> 119452 </DOCNO>
The redshift space power spectrum in the halo model


  Recently there has been a lot of attention focussed on a virialized
halo-based approach to understanding the properties of the matter and galaxy
power spectrum. We show that this model allows a natural treatment of the large
and small scale redshift space distortions, which we develop here, which
extends the pedagogical value of the approach.

</DOC>
<DOC>
<DOCNO> 150710 </DOCNO>
Modular Invariant Critical Superstrings on Four-dimensional Minkowski


  Extending the seminal work of Bilal and Gervais, we construct a tachyon-free,
modular invariant partition function for critical superstrings on
four-dimensional Minkowski x two-dimensional black hole. This model may be
thought of as an SL(2,R)/U(1) version of Gepner models and corresponds to a
conifold point on the moduli space of Calabi-Yau compactifications. We directly
deal with N=2, c=9 unitary superconformal characters. Modular invariance is
achieved by requiring the string to have a momentum along an extra noncompact
direction, in agreement with the picture of singular CFTs advocated by Witten.
The four-dimensional massless spectrum coincides with that of the tensionless
strings, suggesting a possible dual description of type II strings on a
conifold in terms of two intersecting NS5-branes. An interesting relation to
D=6, N=4 gauged supergravity is also discussed.

</DOC>
<DOC>
<DOCNO> 101403 </DOCNO>
Complex numbers in 6 dimensions


  Two distinct systems of commutative complex numbers in 6 dimensions of the
polar and planar types of the form u=x_0+h_1x_1+h_2x_2+h_3x_3+h_4x_4+h_5x_5 are
described in this work, where the variables x_0, x_1, x_2, x_3, x_4, x_5 are
real numbers. The polar 6-complex numbers introduced in this paper can be
specified by the modulus d, the amplitude \rho, and the polar angles \theta_+,
\theta_-, the planar angle \psi_1, and the azimuthal angles \phi_1, \phi_2. The
planar 6-complex numbers introduced in this paper can be specified by the
modulus d, the amplitude \rho, the planar angles \psi_1, \psi_2, and the
azimuthal angles \phi_1, \phi_2, \phi_3. Exponential and trigonometric forms
are given for the 6-complex numbers. The 6-complex functions defined by series
of powers are analytic, and the partial derivatives of the components of the
6-complex functions are closely related. The integrals of polar 6-complex
functions are independent of path in regions where the functions are regular.
The fact that the exponential form of ther 6-complex numbers depends on cyclic
variables leads to the concept of pole and residue for integrals on closed
paths. The polynomials of polar 6-complex variables can be written as products
of linear or quadratic factors, the polynomials of planar 6-complex variables
can always be written as products of linear factors, although the factorization
is not unique.

</DOC>
<DOC>
<DOCNO> 120237 </DOCNO>
Probing Dense Matter in the cores of AGN: Observations with RXTE and


  Preliminary results from an X-ray spectral study of Seyfert 1 galaxies with
ASCA and RXTE are presented. From an analysis of X-ray reprocessing features of
Compton reflection and Fe K-alpha fluorescence, it is found that iron line
strength is not necessarily a good predictor of the amount of reflection. The
variability properties of Fe K-alpha and reflection do not necessarily scale
together and substantial decoupling of the behavior of the reprocessed flux
with respect to continuum variability is common. Such trends suggest the
presence of multiple and/or complex regions of dense matter in AGN cores and
that standard accretion disk models drastically oversimplify reality.

</DOC>
<DOC>
<DOCNO> 9976 </DOCNO>
Strong correlations in low dimensional conductors. What are they, and


  This paper is written as a brief introduction for beginning graduate
students. The picture of electron waves moving in a cristalline potential and
interacting weakly with each other and with cristalline vibrations suffices to
explain the properties of technologically important materials such as
semiconductors and also simple metals that become superconductors. In magnetic
materials, the relevant picture is that of electrons that are completely
localized, spin being left as the only relevant degree of freedom. A number of
recently discovered materials with unusual properties do not fit in any of
these two limiting cases. These challenging materials are generally very
anisotropic, either quasi one-dimensional or quasi two-dimensional, and in
addition their electrons interact strongly but not enough to be completely
localized. High temperature superconductors and certain organic conductors fall
in the latter category. This paper discusses how the effect of low dimension
leads to new paradigms in the one-dimensional case (Luttinger liquids,
spin-charge separation), and indicates some of the attempts that are being
undertaken to develop, concurrently, new methodology and new concepts for the
quasi-two-dimensional case, especially relevant to high-temperature
superconductors.

</DOC>
<DOC>
<DOCNO> 123182 </DOCNO>
Big Bang nucleosynthesis and the baryonic content of the universe


  A review of the latest measurements of the primordial abundances of the light
nuclei D, 3He, 4He and 7Li is given. We discuss in particular the primordial
abundance Yp of 4He as measured in blue compact dwarf galaxies. We argue that
the best measurements now give a ``high'' value of Yp along with a ``low''
value of D/H, and that the two independent measurements are consistent within
the framework of standard Big Bang nucleosynthesis with a number of light
neutrino species Nnu = 3.0+/-0.3 (2sigma).

</DOC>
<DOC>
<DOCNO> 169650 </DOCNO>
Comment on "Quantum Phase Shift Caused by Spatial Confinement", by B.E.


  The analysis of phase shifts in executed and proposed interferometry
experiments on photons and neutrons neglected forces exerted at the boundaries
of spatial constrictions. When those forces are included it is seen that the
observed phenomena are not in fact geometric in nature. A new proposal to be
published by Allman et al. avoids that pitfall.

</DOC>
<DOC>
<DOCNO> 151220 </DOCNO>
Supergravity couplings: a geometric formulation


  This report provides a pedagogical introduction to the description of the
general Poincare supergravity/matter/Yang-Mills couplings using methods of
Kahler superspace geometry. At a more advanced level this approach is
generalized to include tensor field and Chern-Simons couplings in supersymmetry
and supergravity, relevant in the context of weakly and strongly coupled string
theories.

</DOC>
<DOC>
<DOCNO> 122801 </DOCNO>
The LMC eclipsing binary HV 2274 revisited


  We reanalyse the UV/optical spectrum and optical broad-band data of the
eclipsing binary HV 2274 in the LMC, and derive its distance following the
method given by Guinan et al. (1998a,b) of fitting theoretical spectra to the
stars' UV/optical spectrum plus optical photometry. We describe the method in
detail, pointing out the various assumptions that have to be made; moreover, we
discuss the systematic effects of using different sets of model atmospheres and
different sets of optical photometric data. It turns out that different
selections of the photometric data, the set of model atmospheres and the
constraints on the value of the ratio of selective to total extinction in the
$V$-band, result in a 25% range in distances (although some of these models
have a large ${\chi}^2$). For our best choice of these quantities the derived
value for the reddening to HV 2274 is E(B-V) = 0.103 $\pm$ 0.007, and the
de-reddened distance modulus is DM = 18.46 $\pm$ 0.06; the DM to the center of
the LMC is found to be 18.42 $\pm$ 0.07. This is significantly larger than the
DM of 18.30 $\pm$ 0.07 derived by Guinan et al. (1998a).

</DOC>
<DOC>
<DOCNO> 120779 </DOCNO>
CO in Stephan's Quintet: First Evidence of Molecular Gas in the


  We present the first interferometric evidence of CO(1-0) emission in the
intragroup starburst (IGS) region of HCG~92 (Stephan's Quintet). BIMA's large
primary beam covers fully both the IGS region and the dominant group member
galaxy Seyfert NGC 7319, as well as partially the intruder galaxy NGC 7318B. CO
emission of $\approxgt 4\sigma$ is detected in all of them. The detection of
the CO emission associated with the IGS is further supported by comparisons
with observations in other wavebands (e.g., HI, mid-IR, \ha). Assuming the
standard conversion factor, 3.6--8.0$\times 10^8~\Msun$ molecular gas is found
to be associated with the IGS. Confining to the region of the CO emission peak,
a relatively high star-formation efficiency of 8.6$\Lsun/\Msun$ is derived for
the IGS, which is nearly comparable to that of local starburst galaxies (e.g.,
M82).

</DOC>
<DOC>
<DOCNO> 68679 </DOCNO>
The hadronic off-shell width of meson resonances


  Within the resonance chiral effective theory we study the dressed propagators
of the spin-1 fields, as arise from a Dyson-Schwinger resummation
perturbatively constructed from loop diagrams with absorptive contributions in
the s-channel. We apply the procedure to the vector pion form factor and the
elastic pion-pion scattering to obtain the off-shell width of the rho_0 meson.
We adopt a definition of the off-shell width of spin-1 meson resonances that
satisfies the requirements of analyticity, unitarity, chiral symmetry and
asymptotic behaviour ruled by QCD. To fulfil these constraints the resummation
procedure cannot consist only of self-energy diagrams. Our width definition is
shown to be independent of the formulation used to describe the spin-1 meson
resonances.

</DOC>
<DOC>
<DOCNO> 11233 </DOCNO>
Langevin equation of collective modes of Bose-Einstein condensates in


  A quantum Langevin equation for the amplitudes of the collective modes in
Bose-Einstein condensate is derived. The collective modes are coupled to a
thermal reservoir of quasi-particles, whose elimination leads to the quantum
Langevin equation. The dissipation rates are determined via the correlation
function of the fluctuating force and are evaluated in the local-density
approximation for the spectrum of quasi-particles and the Thomas-Fermi
approximation for the condensate. I take great pleasure in dedicating this
paper to Gregoire Nicolis on the occasion of his sixtieth birthday.

</DOC>
<DOC>
<DOCNO> 117752 </DOCNO>
Possible solar cycle variations in the convection zone


  Using data from the Global Oscillations Network Group (GONG) that covers the
period from 1995 to 1998 we study the change in frequencies of solar
oscillations with solar activity. From these frequencies we attempt to
determine any possible variation in solar structure with solar activity. We do
not find any evidence of a change in the convection zone depth or extent of
overshoot below the convection zone during the solar cycle.

</DOC>
<DOC>
<DOCNO> 100633 </DOCNO>
The domain algebra of a CP semigroup


  A CP semigroup is a semigroup of normal unit-preserving completely positive
maps acting on the algebra B(H) of all operators on a separable Hilbert space
H. Such a semigroup has a natural generator L; since the individual maps of the
semigroup need not be multiplicative, the domain Dom(L) of L is typically an
operator system, but not an algebra.
  However, we show that the set of all operators A in Dom(L), with the property
that both A*A and AA* belong to Dom(L), is a *-algebra, called the domain
algebra of the CP semigroup. Using this algebra, it is possible to draw a very
close parallel with the Laplacian of a Riemannian manifold. We discuss
properties of the "symbol" of L as the noncommutative counterpart of a
(semidefinite) Riemannian metric, and give examples for which the domain
algebra is, and is not, strongly dense in B(H).

</DOC>
<DOC>
<DOCNO> 178757 </DOCNO>
Application of the density dependent hadron field theory to neutron star


  The density dependent hadron field (DDRH) theory, previously applied to
isospin nuclei and hypernuclei is used to describe $\beta$-stable matter and
neutron stars under consideration of the complete baryon octet. The
meson-hyperon vertices are derived from Dirac-Brueckner calculations of nuclear
matter and extended to hyperons. We examine properties of density dependent
interactions derived from the Bonn A and from the Groningen NN potential as
well as phenomenological interactions. The consistent treatment of the density
dependence introduces rearrangement terms in the expression for the baryon
chemical potential. This leads to a more complex condition for the
$\beta$-equilibrium compared to standard relativistic mean field (RMF)
approaches. We find a strong dependence of the equation of state and the
particle distribution on the choice of the vertex density dependence. Results
for neutron star masses and radii are presented. We find a good agreement with
other models for the maximum mass. Radii are smaller compared to RMF models and
indicate a closer agreement with results of non-relativistic Brueckner
calculations.

</DOC>
<DOC>
<DOCNO> 8095 </DOCNO>
Large-q expansion for the second moment correlation length in the


  We calculate the large-q expansion of the second moment correlation length at
the first order phase transition point of the q-state Potts model in two
dimensions both in the ordered and disordered phases to order 21 in
$1/\sqrt{q}$. They coincide with each other to the third term of the series but
differ a little in higher orders. Numerically the ratio of the second moment
correlation length in the two phases is not far from unity in all region of
q>4. The ratio of the second moment correlation length to the standard
correlation length in the disordered phase is far from unity, which suggests
that the second largest and smaller eigenvalues of the transfer matrix form a
continuum spectrum not only in the large-q region but also in all the region of
q>4.

</DOC>
<DOC>
<DOCNO> 102209 </DOCNO>
Quantized Dirac Operators


  We determine what should correspond to the Dirac operator on certain
quantized hermitian symmetric spaces and what its properties are. A new insight
into the quantized wave operator is obtained.

</DOC>
<DOC>
<DOCNO> 151550 </DOCNO>
Large Marginal Deformations in String Field Theory


  We use the level truncation scheme to obtain accurate descriptions of open
bosonic string field configurations corresponding to large marginal
deformations such as background Wilson lines. To do so, we solve for all fields
as functions of the massless string field, and confirm that the effective
potential of the massless field becomes increasingly flat as the level of
approximation is increased. Surprisingly, as a result of the merging of two
branches of the solution - one originating at zero tachyon vev and the other
originating at the tachyonic vacuum - this effective potential exists only for
a finite range of values of the massless field. We use the D1 to D0 brane
marginal transition on a circle to explore the possibility that this finite
range corresponds to the infinite range of the conformal field theory parameter
describing marginal deformations, but are unable to arrive at a definitive
conclusion.

</DOC>
<DOC>
<DOCNO> 102594 </DOCNO>
Resolvents and Martin boundaries of product spaces


  In this paper we examine the Laplacian on the product of two asymptotically
hyperbolic (or conformally compact, as they are often called) spaces from the
point of view of geometric scattering theory. In particular, we describe the
asymptotic behavior of the resolvent applied to Schwartz functions and that of
the resolvent kernel itself. We use these results to find the Martin boundary
of the product space. This behaves (nearly) as expected when the factors have
no $L^2$ eigenvalues, but it experiences a substantial collapse in the presence
of such eigenvalues.

</DOC>
<DOC>
<DOCNO> 170707 </DOCNO>
Control of a Coupled Two Spin System Without Hard Pulses


  Constructive methods for controlling a coupled, two spin system via bounded
amplitude, piecewise sinusoidal fields are provided. The fields are incident at
the alrmor frequencies and take one of two phase values

</DOC>
<DOC>
<DOCNO> 80957 </DOCNO>
Matrix model formulation of four dimensional gravity


  The attempt of extending to higher dimensions the matrix model formulation of
two-dimensional quantum gravity leads to the consideration of higher rank
tensor models. We discuss how these models relate to four dimensional quantum
gravity and the precise conditions allowing to associate a four-dimensional
simplicial manifold to Feynman diagrams of a rank-four tensor model.

</DOC>
<DOC>
<DOCNO> 12979 </DOCNO>
Pumping at resonant transmission and transferred charge quantization


  We consider pumping through a small quantum dot separated from the leads by
two point contacts, whose conductances, $G_{1}$ and $G_{2}$, serve as pumping
parameters. When the dot is pincched, we find that there is a "resonance line"
in the parameter plane $\{G_{1}, G_{2}\}$ along which the Fermi energy in the
leads aligns with the energy of the quasi-bound state in the quantum dot. When
$G_{1}$ and $G_{2}$ are modulated periodically and adiabatically such that the
pumping contour defined by $G_{1}=G_{1}(t)$ and $ G_{2}=G_{2}(t)$ encircles the
resonance line, the current is quantized: the charge pumped through the dot
during each period of the modulation is close to a single electronic charge.

</DOC>
<DOC>
<DOCNO> 151229 </DOCNO>
Supergravity Description of Non-BPS Branes


  We construct supergravity solutions that correspond to N Dp-branes coinciding
with \bar{N} \bar{Dp}-branes. We study the physical properties of the solutions
and analyse the supergravity description of tachyon condensation. We construct
an interpolation between the brane-antibrane solution and the Schwarzschild
solution and discuss its possible application to the study of
non-supersymmetric black holes.

</DOC>
<DOC>
<DOCNO> 13729 </DOCNO>
Yang-Lee zeros and the helix-coil transition in a continuum model of


  We calculate the Yang-Lee zeros for characteristic temperatures of the
helix-coil transition in a continuum model of polyalanine. The distribution of
these zeros differs from predictions of the Zimm-Bragg theory and supports
recent claims that polyalanine exhibits a true phase transition. New estimates
for critical exponents are presented and the relation of our results to the
Lee-Yang theorem is discussed.

</DOC>
<DOC>
<DOCNO> 40309 </DOCNO>
First Observation of the Sigma_c^{*+} Charmed Baryon, and New


  Using ~13.7 fb^{-1} of e^+e^- collision data recorded at near the Upsilon(4S)
resonance by the CLEO II and CLEO II.V detector configurations on the Cornell
Electron Storage Ring, we present the world's most precise measurements of the
Sigma_c^0, Sigma_c^+, and Sigma_c^{++} charmed-baryon masses as well as the
first measurements of the intrinsic widths of the Sigma_c^0 and Sigma_c^{++}
baryons. We also report on the first observation and mass measurement of the
Sigma_c^{*+} charmed baryon, M(Sigma_c^{*+}) - M(Lambda_c^+) = (231.0 +-
1.1[stat] +- 2.0[syst]) MeV/c^2, and the first CLEO observation of the
Omega_c^0 baryon, for which we measure a mass M(Omega_c^0) = (2694.6 +-
2.6[stat] +- 1.9[syst]) MeV/c^2 from a sample of (40.4 +- 9.0[stat]) candidate
events. All new results are preliminary.

</DOC>
<DOC>
<DOCNO> 102584 </DOCNO>
A Scaling Law for the Energy Levels of a Nonlinear Schrodinger Equation


  It is shown that the energy levels of the one-dimensional nonlinear
Schrodinger, or Gross-Pitaevskii, equation with the homogeneous trap potential
$x^{2p}$, $p\geq 1$, obey an approximate scaling law and as a consequence the
energy increases approximately linearly with the quantum number. Moreover, for
a quadratic trap, $p=1$, the rate of increase of energy with the quantum number
is independent of the nonlinearity: this prediction is confirmed with numerical
calculations. It is also shown that the energy levels computed using a
variational approximation do not satisfy this scaling law.

</DOC>
<DOC>
<DOCNO> 151820 </DOCNO>
The M2-brane Soliton on the M5-brane with Constant 3-Form


  We obtain a BPS soliton of the effective theory of the M5-brane worldvolume
with constant 3-form representing M2-branes ending on the M5-brane. The
dimensional reduction of this solution agrees with the known results on
D-branes.

</DOC>
<DOC>
<DOCNO> 13682 </DOCNO>
Multi-component structure of nonlinear excitations in systems with


  We investigate the properties of nonlinear excitations in different types of
soliton bearing systems with long-range dispersive interaction. We show that
length-scale competition in such systems universally results in a
multi-component structure of nonlinear excitations and can lead to a new type
of multistability: coexistence of different nonlinear excitations at the same
value of the spectral parameter (i.e., velocity in the case of anharmonic
lattices or frequency in nonlinear Schroedinger models).

</DOC>
<DOC>
<DOCNO> 117872 </DOCNO>
The frequency content of Delta Sct stars as determined by photometry


  The results obtained by means of the photometric approach to the study of
Delta Sct stars are extensively discussed. The different frequency contents of
the three best candidates for asteroseismological studies (FG Vir, 4 CVn and XX
Pyx) are presented and compared; the importance of the amplitude variations and
of the combination terms is emphasized. The analysis of other multiperiodic
variables shows how a large variety of nonradial modes are excited; in some
cases, modifications of the power spectrum can be observed over a few years and
new modes can be seen to grow. Among monoperiodic pulsators, constant as well
as variable amplitudes can be observed. The difficulty of identifying an
oscillation yielding quantum numbers is emphasized; the possibilities offered
by $\delta$ Sct stars belonging to binary systems and open clusters are
discussed. In this respect, combining the photometric and the spectroscopic
approaches could lead to a solution. A comparison is also made between low- and
high-amplitude pulsators, finding similarities. The use of a reliable
Period-Luminosity-Colour relationships toward the shortest periods can greatly
help mode identification in the galactic stars; moreover, it could provide an
independent verification of extragalactic distances.

</DOC>
<DOC>
<DOCNO> 121185 </DOCNO>
From Globular Clusters to Tidal Dwarfs: Structure Formation in Tidal


  Star clusters can be found in galaxy mergers, not only in central regions,
but also in the tidal debris. In both the Eastern and Western tidal tails of
NGC 3256 there are dozens of young star clusters, confirmed by their blue
colors and larger concentration index as compared to sources off of the tail.
Tidal tails of other galaxy pairs do not have such widespread cluster
formation, indicating environmental influences on the process of star formation
or the packaging of the stars.

</DOC>
<DOC>
<DOCNO> 119770 </DOCNO>
Galactic Observations at 31, 42 and 144~GHz with the Mobile Anisotropy


  We present multi-frequency maps of a portion of the Galactic Plane centered
on a declination of -60 degrees with resolutions ranging from 0.2 to 0.9
degrees. The maps are optimized to detect unresolved source emission and are
cross-calibrated against the planet Jupiter. We discuss six millimeter-bright
regions, three of which are visible in all bands, and list measured flux
densities. Variability is limited to less than 3.8% for all sources seen at 31
and 42 GHz and less than 10% at 144 GHz. Fractional polarization limits smaller
than 0.08 are measured for all sources seen at 31 and 42 GHz. No fractional
polarization limits are reported at 144 GHz.

</DOC>
<DOC>
<DOCNO> 102873 </DOCNO>
Stabilisation, bordism and embedded spheres in 4-manifolds


  It is one of the most interesting facts in 4-dimensional topology that even
in simply connected 4-manifolds, not every homology class of degree 2 can be
represented by an embedded sphere. In 1978, M. Freedman and R. Kirby showed
that many of the obstructions against constructing such a sphere vanish if one
modifies the ambient 4-manifold by adding copies of products of spheres, a
process which is usually called stabilisation. In this paper, we extend this
result to non-simply connected 4-manifolds and show how it is related to the
Spin-c bordism groups of Eilenberg-McLane spaces.

</DOC>
<DOC>
<DOCNO> 120369 </DOCNO>
Search for interactions between ejections of GRS 1915+105 and its


  To unravel the effect of likely interactions between the energetic ejections
of the galactic superluminal source GRS 1915+105 and its surrounding
interstellar medium, we observed its environment. Two IRAS sources are
symmetrically placed with respect to GRS 1915+105, and are aligned with the
sub-arcsec ejections of this source.
 We analyzed these two sources IRAS 19124+1106 and IRAS 19132+1035 through
near-infrared, millimeter and centimeter wavelengths. The evidence for these
regions being interaction zones seems inconclusive.

</DOC>
<DOC>
<DOCNO> 101447 </DOCNO>
Infinite Order Amphicheiral Knots


  In answer to a question of Long, Flapan constructed an example of a prime
strongly positive amphicheiral knot that is not slice. Long had proved that all
such knots are algebraically slice. Here we show that the concordance group of
algebraically slice knots contains an infinitely generated free subgroup that
is generated by prime strongly positive amphicheiral knots. A simple corollary
of this result is the existence of positive amphicheiral knots that are not of
order two in concordance.

</DOC>
<DOC>
<DOCNO> 102566 </DOCNO>
The Simple Group of Order 168 and K3 Surfaces


  The aim of this note is to characterize a K3 surface of Klein-Mukai type in
terms of its symmetry.

</DOC>
<DOC>
<DOCNO> 119476 </DOCNO>
Introducing ZEUS-MP: A 3D, Parallel, Multiphysics Code for Astrophysical


  We describe ZEUS-MP: a Multi-Physics, Massively-Parallel, Message-Passing
code for astrophysical fluid dynamics simulations in 3 dimensions. ZEUS-MP is a
follow-on to the sequential ZEUS-2D and ZEUS-3D codes developed and
disseminated by the Laboratory for Computational Astrophysics
(lca.ncsa.uiuc.edu) at NCSA. V1.0 released 1/1/2000 includes the following
physics modules: ideal hydrodynamics, ideal MHD, and self-gravity. Future
releases will include flux-limited radiation diffusion, thermal heat
conduction, two-temperature plasma, and heating and cooling functions. The
covariant equations are cast on a moving Eulerian grid with Cartesian,
cylindrical, and spherical polar coordinates currently supported.
Parallelization is done by domain decomposition and implemented in F77 and MPI.
The code is portable across a wide range of platforms from networks of
workstations to massively parallel processors. Some parallel performance
results are presented as well as an application to turbulent star formation.

</DOC>
<DOC>
<DOCNO> 12674 </DOCNO>
On the nature of the stock market: Simulations and experiments


  In this dissertation two simple models of stock exchange are developed and
simulated numerically. The first is characterized by centralized trading with a
market maker. Unfortunately, this model is unable to generate realistic market
dynamics.
  The second model discards the requirement of centralized trading. Under
variation of the control parameter the model exhibits two phase transitions:
both a first- and a second-order (critical).
  The decentralized model is able to capture many of the interesting properties
observed in empirical markets. Significantly, these properties only emerge when
the parameters are tuned such that the model spans the critical point. This
suggests that real markets may operate at or near a critical point, but is
unable to explain why this should be.
  One of the main points of the thesis is that these empirical phenomena are
not present in the stochastic driving force, but emerge endogenously from
interactions between agents.

</DOC>
<DOC>
<DOCNO> 10252 </DOCNO>
Doping dependent evolution of the electronic structure of La2-xSrxCuO4


  The electronic structure of the La$_{2-x}$Sr$_x$CuO$_4$ (LSCO) system has
been studied by angle-resolved photoemission spectroscopy (ARPES). We report on
the evolution of the Fermi surface, the superconducting gap and the band
dispersion around the extended saddle point $k=(\pi,0)$ with hole doping in the
superconducting and metallic phases. As hole concentration $x$ decreases, the
flat band at $(\pi,0)$ moves from above the Fermi level ($E_F$) for $x>0.2$ to
below $E_F$ for $x<0.2$, and is further lowered down to $x=0.05$. From the
leading-edge shift of ARPES spectra, the magnitude of the superconducting gap
around $(\pi,0)$ is found to monotonically increase as $x$ decreases from
$x=0.30$ down to $x=0.05$ even though $T_c$ decreases in the underdoped region,
and the superconducting gap appears to smoothly evolve into the normal-state
gap at $x=0.05$. It is shown that the energy scales characterizing these
low-energy structures have similar doping dependences. For the heavily
overdoped sample ($x=0.30$), the band dispersion and the ARPES spectral
lineshape are analyzed using a simple phenomenological self-energy form, and
the electronic effective mass enhancement factor $m^*/m_b \simeq 2$ has been
found. As the hole concentration decreases, an incoherent component that cannot
be described within the simple self-energy analysis grows intense in the
high-energy tail of the ARPES peak. Some unusual features of the electronic
structure observed for the underdoped region ($x \lesssim 0.10$) are consistent
with the numerical works on the stripe model.

</DOC>
<DOC>
<DOCNO> 11492 </DOCNO>
Possible ground states of D-wave condensates in isotropic space


  A complete and rigorous determination of the possible ground states for
D-wave pairing Bose condensates is presented. Using an orbit space approach to
the problem, we find 15 allowed phases (besides the unbroken one), with
different symmetries, that we thoroughly determine, specifying the
group-subgroup relations between bordering phases.

</DOC>
<DOC>
<DOCNO> 120003 </DOCNO>
The location of the dense and ionized gas in the NGC 2023 PDR


  The VLA and the BIMA array were used to obtain high resolution (10-20")
observations of C+, traced by the C91a recombination line at 8.6 GHz, and the
dense molecular gas, traced by HCN and HCO+(1-0), of the photon dominated
region (PDR) associated with the reflection nebula NGC 2023. Using the VLA,
continuum emission is detected at 8.6 GHz from a faint HII region associated
with HD 37903. The C91a emission originates from a 0.4 pc long filament,
extending from the east to the south of the exciting star HD 37903. Within the
filament three C91a clumps can be distinguished, each associated with
filamentary vibrationally excited H2 emission in the direction toward HD 37903.
The HCO+ emission has a clumpy appearance superimposed on a more extended
component. C91a is, in general, closer to the exciting star than HCO+ emission
as expected from PDR models. The morphologies of HCO+ and HCN are quite
similar. Based on the C91a linewidth towards one of the clumps a limit of 170 K
on the kinetic temperature in the ionized carbon layer can be derived. This
value is consistent with PDR models with H2 densities of about 10^5/cm^3.
However, this result suggests surprisingly low limits on the turbulence in the
PDR. We detected a compact 3 mm continuum source in the PDR, which appears to
be a cold "core" of density 10^7/cm^3, 0.03 parsec diameter, and 6 solar
masses. We conclude that it may have formed within the PDR. In an appendix,
observations of the C91a recombination line toward five additional PDRs using
the Effelsberg 100m telescope are described.

</DOC>
<DOC>
<DOCNO> 174522 </DOCNO>
The Transverse Asymmetry $\bf A_{\bf T'}$ from Quasi-elastic $^3\vec{\rm


  We have measured the transverse asymmetry from inclusive scattering of
longitudinally polarized electrons from polarized 3He nuclei at quasi-elastic
kinematics in Hall A at Jefferson Lab with high statistical and systematic
precision. The neutron magnetic form factor was extracted based on Faddeev
calculations with an experimental uncertainty of less than 2 %.

</DOC>
<DOC>
<DOCNO> 11539 </DOCNO>
Evolution of coherent islands during strained-layer Volmer-Weber growth


  This paper withdrawn by the authors due to errors in the TEM measurements of
the densities and sizes of small islands.

</DOC>
<DOC>
<DOCNO> 118707 </DOCNO>
Two-dimensional galaxy-galaxy lensing: a direct measure of the


  We propose a new technique to directly measure the shapes of dark matter
halos of galaxies using weak gravitational lensing. Extending the standard
galaxy-galaxy lensing method, we show that the shape parameters of the mass
distribution of foreground galaxies can be measured from the two-dimensional
shear field derived from background galaxies. This enables the comparison of
the ellipticity of the mass distribution with that of the light in galaxies, as
well as an estimate of the degree of alignment between the stellar component
and dark matter. We choose the specific case of an elliptical, isothermal
profile and estimate the feasibility and significance of the detection of this
signal. The prospects for applying this technique are excellent with large
on-going surveys like the Sloan Digital Sky Survey. The expected signal is
smaller, but comparable in significance to that of the mass in standard
galaxy-galaxy lensing analyses. Since shapes of halos depend on the degree of
dissipation and the transfer of angular momentum during galaxy assembly,
constraints obtained from our analysis will provide an important input to
models of galaxy formation.

</DOC>
<DOC>
<DOCNO> 71268 </DOCNO>
Addendum to "A Phenomenological Description of pi- Delta++


  We acknowledge a paper on the same subject by other authors, that we didn't
have the chance to cite in our work. A few comments on the content of the two
papers are made.

</DOC>
<DOC>
<DOCNO> 12356 </DOCNO>
Korringa ratio of ferromagnetically correlated impure metals


  The Korringa ratio, $\cal K$, obtained by taking an appropriate combination
of the Knight shift and nuclear spin-lattice relaxation time, is calculated at
finite temperature, $T$, in the three-dimensional electron gas model, including
the electron-electron interaction, $U$, and non-magnetic impurity scatterings.
$\cal K$ varies in a simple way with respect to $U$ and $T$; it decreases as
$U$ is increased but increases as $T$ is raised. However, $\cal K$ varies in a
slightly more complicated way with respect to the impurity scatterings; as the
scattering rate is increased, $\cal K$ increases for small $U$ and low $T$, but
decreases for large $U$ or high $T$ regime. This calls for a more careful
analysis when one attempts to estimate the Stoner factor from $\cal K$.

</DOC>
<DOC>
<DOCNO> 100458 </DOCNO>
Global Bounds for the Lyapunov Exponent and the Integrated Density of


  In this article we prove an upper bound for the Lyapunov exponent $\gamma(E)$
and a two-sided bound for the integrated density of states $N(E)$ at an
arbitrary energy $E>0$ of random Schr\"odinger operators in one dimension.
These Schr\"odinger operators are given by potentials of identical shape
centered at every lattice site but with non-overlapping supports and with
randomly varying coupling constants. Both types of bounds only involve
scattering data for the single-site potential. They show in particular that
both $\gamma(E)$ and $N(E)-\sqrt{E}/\pi$ decay at infinity at least like
$1/\sqrt{E}$. As an example we consider the random Kronig-Penney model.

</DOC>
<DOC>
<DOCNO> 68758 </DOCNO>
Parametrizing the mixing matrix : A unified approach


  A unified approach to parametrization of the mixing matrix for $N$
generations is developed. This approach not only has a clear geometrical
underpinning but also has the advantage of being economical and recursive and
leads in a natural way to the known phenomenologically useful parametrizations
of the mixing matrix.

</DOC>
<DOC>
<DOCNO> 68827 </DOCNO>
Gravitational wave bursts from cosmic strings


  Cusps of cosmic strings emit strong beams of high-frequency gravitational
waves (GW). As a consequence of these beams, the stochastic ensemble of
gravitational waves generated by a cosmological network of oscillating loops is
strongly non Gaussian, and includes occasional sharp bursts that stand above
the rms GW background. These bursts might be detectable by the planned GW
detectors LIGO/VIRGO and LISA for string tensions as small as $G \mu \sim
10^{-13}$. The GW bursts discussed here might be accompanied by Gamma Ray
Bursts.

</DOC>
<DOC>
<DOCNO> 117448 </DOCNO>
On the Internal Absorption of Galaxy Clusters


  A study of the cores of galaxy clusters with the Einstein SSS indicated the
presence of absorbing material corresponding to 1E+12 Msun of cold cluster gas,
possibly resulting from cooling flows. Since this amount of cold gas is not
confirmed by observations at other wavelengths, we examined whether this excess
absorption is present in the ROSAT PSPC observations of 20 bright galaxy
clusters. For 3/4 of the clusters, successful spectral fits were obtained with
absorption due only to the Galaxy, and therefore no extra absorption is needed
within the clusters, in disagreement with the results from the Einstein SSS
data for some of the same clusters. For 1/4 of the clusters, none of our
spectral fits was acceptable, suggesting a more complicated cluster medium than
the two-temperature and cooling flow models considered here. However, even for
these clusters, substantial excess absorption is not indicated.

</DOC>
<DOC>
<DOCNO> 40276 </DOCNO>
Observation of Anomalous Dimuon Events in the NuTeV Decay Detector


  A search for long-lived neutral particles (N^0) which decay into at least one
muon has been performed using an instrumented decay channel at the E815 (NuTeV)
experiment at Fermilab. The decay channel was composed of helium bags
interspersed with drift chambers, and was used in conjunction with the NuTeV
neutrino detector to search for N^0 decays. The data were examined for
particles decaying into the muonic final states mu mu, mu e, and mu pi. Three
mu mu events were observed over an expected background of 0.040 +/- 0.009
events; no events were observed in the other modes. Although the observed
events share some characteristics with neutrino interactions, the observed rate
is a factor of 75 greater than expected. No Standard Model process appears to
be consistent with this observation.

</DOC>
<DOC>
<DOCNO> 117115 </DOCNO>
Quantized Fractal Space Time and Stochastic Holism


  The space time that is used in relativistic Quantum Mechanics and Quantum
Field Theory is the Minkowski space time. Yet, as pointed out by several
scholars this classical space time is incompatible with the Heisenberg
Uncertainity Principle: We cannot go down to arbitrarily small space time
intervals, let alone space time points. Infact this classical space time is at
best an approximation, and this has been criticised by several scholars. We
investigate, what exactly this approximation entails.

</DOC>
<DOC>
<DOCNO> 170205 </DOCNO>
Quantum versus Classical Learnability


  We consider quantum versions of two well-studied classical learning models:
Angluin's model of exact learning from membership queries and Valiant's
Probably Approximately Correct (PAC) model of learning from random examples. We
give positive and negative results for quantum versus classical learnability.
For each of the two learning models described above, we show that any concept
class is information-theoretically learnable from polynomially many quantum
examples if and only if it is information-theoretically learnable from
polynomially many classical examples. In contrast to this information-theoretic
equivalence betwen quantum and classical learnability, though, we observe that
a separation does exist between efficient quantum and classical learnability.
For both the model of exact learning from membership queries and the PAC model,
we show that under a widely held computational hardness assumption for
classical computation (the intractability of factoring), there is a concept
class which is polynomial-time learnable in the quantum version but not in the
classical version of the model.

</DOC>
<DOC>
<DOCNO> 9462 </DOCNO>
Small Bipolarons in the 2-dimensional Holstein-Hubbard Model. I The


  The spatially localized bound states of two electrons in the adiabatic
two-dimensional Holstein-Hubbard model on a square lattice are investigated
both numerically and analytically. The interplay between the electron-phonon
coupling g, which tends to form bipolarons and the repulsive Hubbard
interaction $\upsilon \geq 0$, which tends to break them, generates many
different ground-states. There are four domains in the $g,\upsilon$ phase
diagram delimited by first order transition lines. Except for the domain at
weak electron-phonon coupling (small g) where the electrons remain free, the
electrons form bipolarons which can 1) be mostly located on a single site
(small $\upsilon$, large g); 2) be an anisotropic pair of polarons lying on two
neighboring sites in the magnetic singlet state (large $\upsilon$, large g); or
3) be a "quadrisinglet state" which is the superposition of 4 electronic
singlets with a common central site. This quadrisinglet bipolaron is the most
stable in a small central domain in between the three other phases. The pinning
modes and the Peierls-Nabarro barrier of each of these bipolarons are
calculated and the barrier is found to be strongly depressed in the region of
stability of the quadrisinglet bipolaron.

</DOC>
<DOC>
<DOCNO> 117231 </DOCNO>
Life in Silico - Simulation of Complex Systems by Enzymatic Computation


  We describe software and a language for quasibiological computations. Its
theoretical basis is a unified theory of complex (adaptive) systems where all
laws are regularities of relations between things or agents, and dynamics is
made from ``atomic constituents'' called enzymes.The notion is abstracted from
biochemistry. The software can be used to simulate physical systems as well as
basic life processes. Systems can be constructed and manipulated by mouse click
and there is an automatic translation of all operations into a LISP-like
scripting language, so that one may compose code by mouse click.

</DOC>
<DOC>
<DOCNO> 71562 </DOCNO>
Global fit to the charged leptons DIS data: \boldmath{$\alpha_{\rm s}$,}


  We perform the NLO QCD analysis of the world data on inclusive deep inelastic
scattering cross sections of charged leptons off the proton and the deuterium
targets. The parton distributions, the value of strong coupling constant
$\alpha_{\rm s}$, and the twist 4 contributions to the structure functions
$F_2$ and $F_{\rm L}$ are extracted with the complete account for the
correlations of data points due to the systematic errors. Sensitivity of the
$\alpha_{\rm s}$ value and the high twist contribution to the procedures of
accounting for the systematic errors is studied. The impact of theoretical
uncertainties on the value of $\alpha_{\rm s}$ and on the parton distributions
is analysed. The obtained value of strong coupling constant with the account of
these uncertainties is $\alpha_{\rm s}(M_{\rm Z})=0.1165\pm0.0017({\rm
stat+syst}) \pm^{0.0026}_{0.0034}({\rm theor})$. The uncertainties of
parton-parton luminosities for the FNAL and LHC colliders are estimated.

</DOC>
<DOC>
<DOCNO> 117408 </DOCNO>
Observation of Microlensing towards the Galactic Spiral Arms. EROS II 3


  We present an analysis of the light curves of 9.1 million stars observed
during three seasons by EROS (Experience de Recherche d'Objets Sombres), in the
Galactic plane away from the bulge. Seven stars exhibit luminosity variations
compatible with gravitational microlensing effects due to unseen objects. The
corresponding optical depth, averaged over four directions, is tau = 0.45 +0.24
-0.11 x 10^-6. While this value is compatible with expectations from simple
galactic models under reasonable assumptions on the target distances, we find
an excess of events with short timescale towards the direction closest to the
Galactic Centre.

</DOC>
<DOC>
<DOCNO> 12820 </DOCNO>
Charge renormalization and phase separation in colloidal suspensions


  We explore the effects of counterion condensation on fluid-fluid phase
separation in charged colloidal suspensions. It is found that formation of
double layers around the colloidal particles stabilizes suspensions against
phase separation. Addition of salt, however, produces an instability which, in
principle, can lead to a fluid-fluid separation. The instability, however, is
so weak that it should be impossible to observe a fully equilibrated
coexistence experimentally.

</DOC>
<DOC>
<DOCNO> 8884 </DOCNO>
The Structure of a Vortex in the t-J Model


  We study the single-vortex solution of the t-J model within
resonating-valence-bond (RVB) mean-field theory. We find two types of vortex
cores, insulating and metallic, depending on the parameters of the model. The
pairing order parameter near both cores have $d_{x^2 -y^2}+i\eta d_{xy}$
symmetry. For some range of $t/J$ the calculated tunneling spectrum of the
metallic vortex core agrees qualitatively with the STM tunneling data for
BSCCO.

</DOC>
<DOC>
<DOCNO> 85169 </DOCNO>
Does the third law of black hole thermodynamics really have a serious


  The almost perfect correspondence between certain laws of classical black
hole mechanics and the ordinary laws of thermodynamics is spoiled by the
failure of the conventional back hole analogue of the third law. Our aim here
is to contribute to the associated discussion by flashing light on some simple
facts of black hole physics. However, no attempt is made to lay to rest the
corresponding long lasting debate. Instead, merely some evidence is provided to
make it clear that although the borderline between extremal and non-extremal
black holes is very thin they are essentially different. Hopefully, a careful
investigation of the related issues will end up with an appropriate form of the
third law and hence with an unblemished setting of black hole thermodynamics.

</DOC>
<DOC>
<DOCNO> 150810 </DOCNO>
Quantum Groups and Field Theory


  When the symmetry of a physical theory describing a finite system is deformed
by replacing its Lie group by the corresponding quantum group, the operators
and state function will lie in a new algebra describing new degrees of freedom.
If the symmetry of a field theory is deformed in this way, the enlarged state
space will again describe additional degrees of freedom, and the energy levels
will acquire fine structure. The massive particles will have a stringlike
spectrum lifting the degeneracy of the point-particle theory, and the resulting
theory will have a non-local description. Theories of this kind naturally
contain two sectors with one sector lying close to the standard theory while
the second sector describes particles that should be more difficult to observe.

</DOC>
<DOC>
<DOCNO> 83067 </DOCNO>
Multi-Agent Only Knowing


  Levesque introduced a notion of ``only knowing'', with the goal of capturing
certain types of nonmonotonic reasoning. Levesque's logic dealt with only the
case of a single agent. Recently, both Halpern and Lakemeyer independently
attempted to extend Levesque's logic to the multi-agent case. Although there
are a number of similarities in their approaches, there are some significant
differences. In this paper, we reexamine the notion of only knowing, going back
to first principles. In the process, we simplify Levesque's completeness proof,
and point out some problems with the earlier definitions. This leads us to
reconsider what the properties of only knowing ought to be. We provide an axiom
system that captures our desiderata, and show that it has a semantics that
corresponds to it. The axiom system has an added feature of interest: it
includes a modal operator for satisfiability, and thus provides a complete
axiomatization for satisfiability in the logic K45.

</DOC>
<DOC>
<DOCNO> 71758 </DOCNO>
Massless QCD_2 From Current Constituents


  We discuss the spectra of multi-flavor massless QCD_2. An approximation in
which the Hilbert space is truncated to two currents states is used. We write
down a 't Hooft like equation for the wave function of the two currents states.
We solve this equation for the lowest massive state and find an excellent
agreement with the DLCQ results. In addition, the 't Hooft model and the large
N_f limit spectra are re-derived by using a description in terms of currents.

</DOC>
<DOC>
<DOCNO> 117932 </DOCNO>
5cm OH masers as diagnostics of physical conditions in star-forming


  We demonstrate that the observed characteristics of the 5 cm OH masers in
star-forming regions can be explained with the same model and the same
parameters as the 18 cm and the 6 cm OH masers. In our already published study
of the 18 cm and the 6 cm OH masers in star-forming regions we had examined the
pumping of the 5 cm masers, but did not report the results we had found because
of some missing collision rate coefficients, which in principle could be
important. The recently published observations on the 5 cm masers of OH
encourage us to report our old calculations along with some new ones that we
have performed. These calculations, in agreement with the observations, reveal
the main lines at 5 cm as strong masers, the 6049 MHz satellite line as a weak
maser, and the 6017 MHz satellite line as never inverted for reasonable values
of the parameters

</DOC>
<DOC>
<DOCNO> 120075 </DOCNO>
The transient X-ray source SAX J2239.3+6116 and its optical counterpart


  We have discovered with the Wide Field Cameras on board BeppoSAX the weak
transient X-ray source SAXJ2239.3+6116 whose position coincides with that of
4U2238+60/3A2237+608 and is close to that of the fast transient AT2238+60 and
the unidentified EGRET source 3EG2227+6122. The data suggest that the source
exhibits outbursts that last for a few weeks and peak to a flux of 4E-10
erg/s/cm2 (2-10 keV) at maximum. During the peak the X-ray spectrum is hard
with a photon index of -1.1+/-0.1. Follow-up observations with the Narrow-Field
Instruments on the same platform revealed a quiescent emission level that is
1E+3 times less. Searches through the data archive of the All-Sky Monitor on
RXTE result in the recognition of five outbursts in total from this source
during 1996-1999, with a regular interval time of 262 days. Optical
observations with the KPNO 2.1 m telescope provide a likely optical
counterpart. It is a B0 V to B2 III star with broadened emission lines at an
approximate distance of 4.4 kpc. The distance implies a 2-10 keV luminosity in
the range from 1E+33 to 1E+36 erg/s. The evidence suggests that SAXJ2239.3+6116
is a Be X-ray binary with an orbital period of 262 days.

</DOC>
<DOC>
<DOCNO> 85080 </DOCNO>
On Lame's equation of a particular kind


  It is shown that the Lame's equation ${d^{2}\over d z^{2}}X+\kappa^{2}
cn^{2}(z, {1\over \sqrt 2})X=0$ can be reduced to the hyper-geometric equation.
The characteristic exponents of this equation are expressed in terms of
elementary functions of the parameter $\kappa$. An analytical condition for
parametric amplification is obtained.

</DOC>
<DOC>
<DOCNO> 9078 </DOCNO>
Photoemission and the Origin of High Temperature Superconductivity


  The condensation energy can be shown to be a moment of the change in the
occupied part of the spectral function when going from the normal to the
superconducting state. As a consequence, there is a one to one correspondence
between the energy gain associated with forming the superconducting ground
state, and the dramatic changes seen in angle resolved photoemission spectra.
Some implications this observation has are offered.

</DOC>
<DOC>
<DOCNO> 11375 </DOCNO>
Coherence in a coupled network: Implication for brain function


  In many body systems, constituents interact with each other, forming a
recursive pattern of mutual interaction and giving rise to many interesting
phenomena. Based upon concepts of the modern many body theory, a model for a
generic many body system is developed. A novel approach is used to investigate
the general features in such a system. An interesting phase transition in the
system is found. Possible link to brain dynamics is discussed. It is shown how
some of the basic brain processes, such as learning and memory, find therein a
natural explanation.

</DOC>
<DOC>
<DOCNO> 71053 </DOCNO>
Propagation et oscillations en theorie des champs


  After a review of the problems associated with the conventional treatment of
particle oscillations, an oscillation formula is derived within the framework
of quantum field theory. The oscillating particle is represented by its
propagator and the initial and final states by wave packets. It is obviously
relativistic from the start and moreover applies both to stable (neutrinos) and
unstable particles (K and B mesons, unstable neutrinos). CPLEAR and DAFNE
experiments are studied as examples, with special attention directed to CP
violation. The problems resulting from equal energies/momentum/velocities
prescriptions are analyzed and solved. Oscillations of associated particles are
found to be nonexistent. The relativistic generalization of the
Wigner-Weisskopf equation is also derived.

</DOC>
<DOC>
<DOCNO> 13773 </DOCNO>
Pressure, Resistance, and Current Activation of Anisotropic Compressible


  Thermodynamic and electric properties of anisotropic compressible Hall states
at higher Landau levels are studied using a mean field theory on the von
Neumann lattice basis. It is shown that resistances agree with the recent
experiments of anisotropic compressible states and the states have negative
pressure. As implications, the collapse phenomena of the integer quantum Hall
effect are discussed.

</DOC>
<DOC>
<DOCNO> 117708 </DOCNO>
Gamma-Ray Bursts via Pair Plasma Fireballs from Heated Neutron Stars


  In this paper we model the emission from a relativistically expanding
electron-positron pair plasma fireball originating near the surface of a heated
neutron star. This pair fireball is deposited via the annihilation of neutrino
pairs emanating from the surface of the hot neutron star. The heating of
neutron stars may occur in close neutron star binary systems near their last
stable orbit. We model the relativistic expansion and subsequent emission of
the plasma and find 10^51 to 10^52 ergs in gamma-rays are produced with
spectral and temporal properties consistent with observed gamma-ray bursts.

</DOC>
<DOC>
<DOCNO> 151902 </DOCNO>
Gravitational Interaction of Higher Spin Massive Fields and String


  We discuss the problem of consistent description of higher spin massive
fields coupled to external gravity. As an example we consider massive field of
spin 2 in arbitrary gravitational field. Consistency requires the theory to
have the same number of degrees of freedom as in flat spacetime and to describe
causal propagation. By careful analysis of lagrangian structure of the theory
and its constraints we show that there exist at least two possibilities of
achieving consistency. The first possibility is provided by a lagrangian on
specific manifolds such as static or Einstein spacetimes. The second
possibility is realized in arbitrary curved spacetime by a lagrangian
representing an infinite series in curvature. In the framework of string theory
we derive equations of motion for background massive spin 2 field coupled to
gravity from the requirement of quantum Weyl invariance. These equations appear
to be a particular case of the general consistent equations obtained from the
field theory point of view.

</DOC>
<DOC>
<DOCNO> 80867 </DOCNO>
Monte Carlo Study of Two-Color QCD with Finite Chemical Potential -


  Using Wilson fermions, we study SU(2) lattice QCD with the chemical potential
at $\beta=1.6$. The ratio of fermion determinants is evaluated at each
Metropolis link update step. We calculate the baryon number density, the
Polyakov loops and the pseudoscalar and vector masses on $4^4$ and $4^3\times
8$ lattices. Preliminary data show the pseudoscalar meson becomes massive
around $\mu=0.4$, which indicates the chiral symmetry restoration. The
calculation is broken down when approaching to the transition region. We
analyze the behavior of the fermion determinant and eigen value distributions
of the determinant, which shows a peculiar ``Shell-and-Bean'' pattern near the
transition.

</DOC>
<DOC>
<DOCNO> 83429 </DOCNO>
Using Modes to Ensure Subject Reduction for Typed Logic Programs with


  We consider a general prescriptive type system with parametric polymorphism
and subtyping for logic programs. The property of subject reduction expresses
the consistency of the type system w.r.t. the execution model: if a program is
"well-typed", then all derivations starting in a "well-typed" goal are again
"well-typed". It is well-established that without subtyping, this property is
readily obtained for logic programs w.r.t. their standard (untyped) execution
model. Here we give syntactic conditions that ensure subject reduction also in
the presence of general subtyping relations between type constructors. The idea
is to consider logic programs with a fixed dataflow, given by modes.

</DOC>
<DOC>
<DOCNO> 99588 </DOCNO>
On the complete ionization of a periodically perturbed quantum system


  We analyze the time evolution of a one-dimensional quantum system with zero
range potential under time periodic parametric perturbation of arbitrary
strength and frequency. We show that the projection of the wave function on the
bound state vanishes, i.e. the system gets fully ionized, as time grows
indefinitely.

</DOC>
<DOC>
<DOCNO> 151232 </DOCNO>
D-Branes And Mirror Symmetry


  We study (2,2) supersymmetric field theories on two-dimensional worldsheet
with boundaries. We determine D-branes (boundary conditions and boundary
interactions) that preserve half of the bulk supercharges in non-linear sigma
models, gauged linear sigma models, and Landau-Ginzburg models. We identify a
mechanism for brane creation in LG theories and provide a new derivation of a
link between soliton numbers of the massive theories and R-charges of vacua at
the UV fixed point. Moreover we identify Lagrangian submanifolds that arise as
the mirror of certain D-branes wrapped around holomorphic cycles of K\"ahler
manifolds. In the case of Fano varieties this leads to the explanation of Helix
structure of the collection of exceptional bundles and soliton numbers, through
Picard-Lefshetz theory applied to the mirror LG theory. Furthermore using the
LG realization of minimal models we find a purely geometric realization of
Verlinde Algebra for SU(2) level k as intersection numbers of D-branes. This
also leads to a direct computation of modular transformation matrix and
provides a geometric interpretation for its role in diagonalizing the Fusion
algebra.

</DOC>
<DOC>
<DOCNO> 8377 </DOCNO>
Bunching of fluxons by the Cherenkov radiation in Josephson multilayers


  A single magnetic fluxon moving at a high velocity in a Josephson multilayer
(e.g., high-temperature superconductor such as BSCCO) can emit electromagnetic
waves (Cherenkov radiation), which leads to formation of novel stable dynamic
states consisting of several bunched fluxons. We find such bunched states in
numerical simulation in the simplest cases of two and three coupled junctions.
At a given driving current, several different bunched states are stable and
move at velocities that are higher than corresponding single-fluxon velocity.
These and some of the more complex higher-order bunched states and transitions
between them are investigated in detail.

</DOC>
<DOC>
<DOCNO> 117039 </DOCNO>
Experimental test of local realism using non-maximally entangled states


  In this paper we describe a test of Bell inequalities using a non- maximally
entangled state, which represents an important step in the direction of
eliminating the detection loophole. The experiment is based on the creation of
a polarisation entangled state via the superposition, by use of an appropriate
optics, of the spontaneous fluorescence emitted by two non-linear crystals
driven by the same pumping laser.

</DOC>
<DOC>
<DOCNO> 100252 </DOCNO>
How to Uncross Some Modular Metrics


  Let $\mu$ be a metric on a set T, and let c be a nonnegative function on the
unordered pairs of elements of a superset $V\supseteq T$. We consider the
problem of minimizing the inner product $c\cdot m$ over all semimetrics m on V
such that m coincides with $\mu$ within T and each element of V is at zero
distance from T (a variant of the {\em multifacility location problem}). In
particular, this generalizes the well-known multiterminal multiway) cut
problem. Two cases of metrics $\mu$ have been known for which the problem can
be solved in polynomial time: (a) $\mu$ is a modular metric whose underlying
graph $H(\mu)$ is hereditary modular and orientable (in a certain sense); and
(b) $\mu$ is a median metric. In the latter case an optimal solution can be
found by use of a cut uncrossing method. \Xcomment{We give a common
generalization for both cases by proving that the problem is in P for any
modular metric $\mu$ whose all orbit graphs are hereditary modular and
orientable. To this aim, we show the existence of a retraction of the Cartesian
product of the orbit graphs to $H(\mu)$, which enables us to elaborate an
analog of the cut uncrossing method for such metrics $\mu$.} In this paper we
generalize the idea of cut uncrossing to show the polynomial solvability for a
wider class of metrics $\mu$, which includes the median metrics as a special
case. The metric uncrossing method that we develop relies on the existence of
retractions of certain modular graphs. On the negative side, we prove that for
$\mu$ fixed, the problem is NP-hard if $\mu$ is non-modular or $H(\mu)$ is
non-orientable.

</DOC>
<DOC>
<DOCNO> 118325 </DOCNO>
Very High-Energy Gamma-Ray Observations of PSR B1509-58 with the


  The gamma-ray pulsar PSR B1509-58 and its surrounding nebulae have been
observed with the CANGAROO 3.8m imaging atmospheric Cherenkov telescope. The
observations were performed from 1996 to 1998 in Woomera, South Australia,
under different instrumental conditions with estimated threshold energies of
4.5 TeV (1996), 1.9 TeV (1997) and 2.5 TeV (1998) at zenith angles of ~30 deg.
Although no strong evidence of the gamma-ray emission was found, the lowest
energy threshold data of 1997 showed a marginal excess of gamma-ray--like
events at the 4.1 sigma significance level. The corresponding gamma-ray flux is
calculated to be (2.9 +/- 0.7) * 10^{-12}cm^{-2}s^{-1} above 1.9 TeV. The
observations of 1996 and 1998 yielded only upper limits (99.5% confidence
level) of 1.9 * 10^{-12}cm^{-2}s^{-1} above 4.5 TeV and 2.0 *
10^{-12}cm^{-2}s^{-1} above 2.5 TeV, respectively. Assuming that the 1997
excess is due to Very High-Energy (VHE) gamma-ray emission from the pulsar
nebula, our result, when combined with the X-ray observations, leads to a value
of the magnetic field strength ~5 micro G. This is consistent with the
equipartition value previously estimated in the X-ray nebula surrounding the
pulsar. No significant periodicity at the 150ms pulsar period has been found in
any of the three years' data. The flux upper limits set from our observations
are one order of magnitude below previously reported detections of pulsed TeV
emission.

</DOC>
<DOC>
<DOCNO> 70158 </DOCNO>
Large Dimensions and String Physics in Future Colliders


  We review the status of low-scale string theories and large extra-dimensions.
After an overview on different string realizations, we discuss some of the main
important problems and we summarize present bounds on the size of possible
extra-dimensions from collider experiments.

</DOC>
<DOC>
<DOCNO> 150742 </DOCNO>
Two-Time Physics in Field Theory


  A field theory formulation of two-time physics in d+2 dimensions is obtained
from the covariant quantization of the constraint system associated with the
OSp(n|2) worldline gauge symmetries of two-time physics. Interactions among
fields can then be included consistently with the underlying gauge symmetries.
Through this process a relation between Dirac's work in 1936 on conformal
symmetry in field theory and the more recent worldline formulation of two-time
physics is established while providing a worldline gauge symmetry basis for the
field equations in d+2 dimensions. It is shown that the field theory formalism
goes well beyond Dirac's goal of linearizing conformal symmetry. In accord with
recent results in the worldline approach of two-time physics, the d+2 field
theory can be brought down to diverse d dimensional field theories by solving
the subset of field equations that correspond to the ``kinematic'' constraints.
This process embeds the one ``time'' in d-dimensions in different ways inside
the d+2 dimensional spacetime. Thus, the two-time d+2 field theory appears as a
more fundamental theory from which many one-time d dimensional field theories
are derived. It is suggested that the hidden symmetries and relations among
computed quantities in certain d-dimensional interacting field theories can be
taken as the evidence for the presence of a higher unifying structure in a d+2
dimensional spacetime. These phenomena have similarities with ideas such as
dualities, AdS-CFT correspondence and holography.

</DOC>
<DOC>
<DOCNO> 119221 </DOCNO>
Transient Gamma Ray Spectrometer Measurements of Gamma-Ray Lines from


  The good energy resolution (3--4 keV FWHM) of the Transient Gamma Ray
Spectrometer (TGRS) on board the WIND spacecraft makes it sensitive to
Doppler-shifted outbursts of 511 keV electron-positron annihilation radiation,
the reason being that the Doppler shift causes the cosmic line to be slightly
offset from a strong instrumental background 511 keV line at rest, which is
ubiquitous in space environments. Such a cosmic line (blueshifted) is predicted
to arise in classical novae due to the annihilation of positrons from
$\beta$-decay on a timescale of a few hours in an expanding envelope. A further
advantage of TGRS - its broad field of view, containing the entire southern
ecliptic hemisphere - has enabled us to make a virtually complete and unbiased
3-year search for classical novae at distances up to ~1 kpc. We present
negative results of this search, and estimate its implications for the
highly-uncertain Galactic classical nova rate and for future space missions.

</DOC>
<DOC>
<DOCNO> 10310 </DOCNO>
Nonlinear evolution of step meander during growth of a vicinal surface


  Step meandering due to a deterministic morphological instability on vicinal
surfaces during growth is studied. We investigate nonlinear dynamics of a step
model with asymmetric step kinetics, terrace and line diffusion, by means of a
multiscale analysis. We give the detailed derivation of the highly nonlinear
evolution equation on which a brief account has been given [Pierre-Louis et.al.
PRL(98)]. Decomposing the model into driving and relaxational contributions, we
give a profound explanation to the origin of the unusual divergent scaling of
step meander ~ 1/F^{1/2} (where F is the incoming atom flux). A careful
numerical analysis indicates that a cellular structure arises where plateaus
form, as opposed to spike-like structures reported erroneously in Ref.
[Pierre-Louis et.al. PRL(98)]. As a robust feature, the amplitude of these
cells scales as t^{1/2}, regardless of the strength of the Ehrlich-Schwoebel
effect, or the presence of line diffusion. A simple ansatz allows to describe
analytically the asymptotic regime quantitatively. We show also how
sub-dominant terms from multiscale analysis account for the loss of up-down
symmetry of the cellular structure.

</DOC>
<DOC>
<DOCNO> 100637 </DOCNO>
Fuchsian affine actions of surface groups


  We define a fuchsian affine action of a surface group to be such that the
linear part factors through a representation of $SL(2,{\mathbb R})$. We prove a
fuchsian affine action of a surface group is never proper.

</DOC>
<DOC>
<DOCNO> 85034 </DOCNO>
Quantum theory without Hilbert spaces


  Quantum theory does not only predict probabilities, but also relative phases
for any experiment, that involves measurements of an ensemble of systems at
different moments of time. We argue, that any operational formulation of
quantum theory needs an algebra of observables and an object that incorporates
the information about relative phases and probabilities. The latter is the
(de)coherence functional, introduced by the consistent histories approach to
quantum theory. The acceptance of relative phases as a primitive ingredient of
any quantum theory, liberates us from the need to use a Hilbert space and
non-commutative observables. It is shown, that quantum phenomena are adequately
described by a theory of relative phases and non-additive probabilities on the
classical phase space. The only difference lies on the type of observables that
correspond to sharp measurements. This class of theories does not suffer from
the consequences of Bell's theorem (it is not a theory of Kolmogorov
probabilities) and Kochen- Specker's theorem (it has distributive "logic"). We
discuss its predictability properties, the meaning of the classical limit and
attempt to see if it can be experimentally distinguished from standard quantum
theory. Our construction is operational and statistical, in the spirit of
Kopenhagen, but makes plausible the existence of a realist, geometric theory
for individual quantum systems.

</DOC>
<DOC>
<DOCNO> 72278 </DOCNO>
Markov-Yukawa Transversality Principle And 3D-4D Interlinkage Of


  This article is designed to focus attention on the Markov-Yukawa
Transversality Principle (MYTP) as a novel paradigm for an exact 3D-4D
interlinkage between the corresponding BSE amplitudes, with a closely parallel
treatment of $q{\bar q}$ and $qqq$ systems, stemming from a common 4-fermion
Lagrangian mediated by gluon (vector)-like exchange. This unique feature of
MYTP owes its origin to a Lorentz- covariant 3D support to the BS kernel, which
acts as a sort of `gauge principle' and distinguishes it from most other 3D
approaches to strong interaction dynamics. Some of the principal approaches in
the latter category are briefly reviewed so as to set the (less familiar) MYTP
in their context. Two specific types of MYTP which provide 3D support to the
BSE kernel, are considered: a) Covariant Instantaneity Ansatz (CIA); b)
Covariant LF/NP ansatz (Cov.LF). Both lead to formaly identical 3D BSE
reductions but produce sharply different 4D structures: Under CIA, the 4D loop
integrals suffer from Lorentz mismatch of the vertex functions, leading to
ill-defined time-like momentum integrals, but Cov LF is free from this disease.
This is illustrated by the pion form factor under Cov LF. The reconstruction of
the 4D $qqq$ wave function is achieved by Green's function techniques. PACS:
11.10 st ; 12.38 Lg ; 13.40.Fn. Keywords: Tamm-Dancoff, Bethe-Salpeter,
Quasi-potentials, Light-front (LF), Markov-Yukawa, 3D-4D Interlinkage, CIA,
Cov-LF, Spectroscopy.

</DOC>
<DOC>
<DOCNO> 7872 </DOCNO>
Collective Modes and Electronic Raman Scattering in the Cuprates


  While the low frequency electronic Raman response in the superconducting
state of the cuprates can be largely understood in terms of a d-wave energy
gap, a long standing problem has been an explanation for the spectra observed
in A_{1g} polarization orientations. We present calculations which suggest that
the peak position of the observed A_{1g} spectra is due to a collective spin
fluctuation mode.

</DOC>
<DOC>
<DOCNO> 119207 </DOCNO>
Measurements with the Chandra X-Ray Observatory's flight contamination


  NASA's Chandra X-ray Observatory includes a Flight Contamination Monitor
(FCM), a system of 16 radioactive calibration sources mounted to the inside of
the Observatory's forward contamination cover. The purpose of the FCM is to
verify the ground-to-orbit transfer of the Chandra flux scale, through
comparison of data acquired during the ground calibration with those obtained
in orbit, immediately prior to opening the Observatory's sun-shade door. Here
we report results of these measurements, which place limits on the change in
mirror--detector system response and, hence, on any accumulation of molecular
contamination on the mirrors' iridium-coated surfaces.

</DOC>
<DOC>
<DOCNO> 116915 </DOCNO>
RF System Upgrades to the Advanced Photon Source Linear Accelerator in


  The S-band linear accelerator, which was built to be the source of particles
and the front end of the Advanced Photon Source injector, is now also being
used to support a low-energy undulator test line (LEUTL) and to drive a
free-electron laser (FEL). The more severe rf stability requirements of the FEL
have resulted in an effort to identify sources of phase and amplitude
instability and implement corresponding upgrades to the rf generation chain and
the measurement system. Test data and improvements implemented and planned are
described

</DOC>
<DOC>
<DOCNO> 117682 </DOCNO>
A Third Star in the T Tauri System


  New speckle-holographic images of the T Tauri Infrared Companion (T Tauri
IRC; T Tauri S) reveal it to be a double system with a sky-projected separation
of 0".05, corresponding to a linear distance of 7 AU. The presence of this
third star may account for the relative paucity of dust surrounding the IRC.

</DOC>
<DOC>
<DOCNO> 69846 </DOCNO>
epsilon'/epsilon and Rare K and B Decays in the MSSM


  We analyze the CP violating ratio epsilon'/epsilon and rare K and B decays in
the MSSM with minimal flavour and CP violation, including NLO QCD corrections
and imposing constraints on the supersymmetric parameters coming from epsilon,
B_{d,s}^0-\bar B_{d,s}^0 mixings, B to X_s gamma, Delta rho in the electroweak
precision studies and from the lower bound on the neutral Higgs mass. We
provide a compendium of phenomenologically relevant formulae in the MSSM.
Denoting by T(Q) the MSSM prediction for a given quantity normalized to the
Standard Model result we find the ranges: 0.53 < T(epsilon'/epsilon) < 1.07,
0.65 < T(K^+ to pi^+ nu nubar) < 1.02, 0.41 < T(K_L to pi^0 nu nubar) < 1.03,
0.48 < T(K_L to pi^0 e^+ e^-) < 1.10, 0.73 < T(B to X_s nu nubar) < 1.34 and
0.68 < T(B_s to mu^+ mu^-) < 1.53. We point out that these ranges will be
considerably reduced when the lower bounds on the neutral Higgs mass and tan
beta improve. Some contour plots illustrate the dependences of the quantities
above on the relevant supersymmetric parameters. As a byproduct of this work we
update our previous analysis of epsilon'/epsilon in the SM and find in NDR
epsilon'/epsilon = (9.2^{+6.8}_{-4.0}), a value 15 % higher than in our 1999
analysis.

</DOC>
<DOC>
<DOCNO> 120819 </DOCNO>
Gas/Star Offsets in Tidal Tails


  We use numerical simulations to study the development of gas/star offsets in
the tidal tails of merging galaxies. These offsets are shown to be a natural
consequence of the radially extended HI spatial distribution in disk galaxies,
coupled with internal dissipation in the gaseous component driven by the
interaction. This mechanism explains the observed gas/star offsets in
interacting galaxies without invoking interactions with a hot (unseen) gaseous
component.

</DOC>
<DOC>
<DOCNO> 12471 </DOCNO>
Ferromagnetism in Insulating, Doped Diluted Magnetic Semiconductors


  We report results of a Monte Carlo study of doped, diluted magnetic
semiconductors in the low carrier density (insulating) regime. We find that the
system undergoes a transition from a paramagnet at high temperatures to a
ferromagnet at low temperatures. However, in strong contrast to uniform
systems, disorder effects dominate the entire collective behavior, leading to
very unconventional properties such as (1) magnetization curves that cannot be
described by theories based on critical fluctuations, or on spin wave analysis
over any significant fraction of the phase diagram; (2) a large peak in
susceptibilty well below the ordering temperature; and (3) specific heat curves
that point out the inadequacy of a classical Heisenberg model for spin-5/2 Mn
ions. A picture of percolating magnetic polarons appears to describe the data
well, and leads to a prescription for correcting the unphysical results of the
classical continuous spin model in terms of a discrete vector model.

</DOC>
<DOC>
<DOCNO> 8885 </DOCNO>
Haldane-gap excitations in the low-H_c 1-dimensional quantum


  Inelastic neutron scattering on deuterated single-crystal samples is used to
study Haldane-gap excitations in the new S=1 one-dimensional quantum
antiferromagnet NDMAP, that was recently recognized as an ideal model system
for high-field studies. The Haldane gap energies $\Delta_x=0.42$ meV,
$\Delta_y=0.52$ meV and $\Delta_z=1.86$ meV, for excitations polarized along
the a, b, and c crystallographic axes, respectively, are directly measured. The
dispersion perpendicular to the chain axis c is studied, and extremely weak
inter-chain coupling constants $J_y=1.8\cdot 10^{-3}$ meV and $J_x=3.5\cdot
10^{-4}$ meV, along the a and b axes, respectively, are determined. The results
are discussed in the context of future experiments in high magnetic fields.

</DOC>
<DOC>
<DOCNO> 99374 </DOCNO>
Goldstone Boson Normal Coordinates


  The phenomenon of spontaneous symmetry breaking is well known. It is known to
be accompanied with the appearance of the `Goldstone boson'. In this paper we
construct the canonical coordinates of the Goldstone boson, for quantum spin
systems with short range as well as long range interactions.

</DOC>
<DOC>
<DOCNO> 117073 </DOCNO>
Exotic Ion-Beams, Targets and Sources


  Exotic beams of short-lived radioisotopes are produced in nuclear reactions
such as thermal neutron induced fission, target or projectile fragmentation and
fusion reactions. For a given radioactive ion beam (RIB), different production
modes are in competition. For each of them the cross section, the intensity of
the projectile beam and the target thickness define an upper production rate.
The final yield relies on the optimisation of the ion-source, which should be
fast and highly efficient in view of the limited production cross section, and
on obtaining a minimum diffusion time out of the target matrix or fragment
catcher to reduce decay losses. Eventually, either chemical or isobaric
selectivity is needed to confine unwanted elements near to the production site.
These considerations are discussed for pulsed or dc-driven RIB facilities and
the solutions to some of the technical challenges will be illustrated by
examples of currently produced near-drip-line elements.

</DOC>
<DOC>
<DOCNO> 101582 </DOCNO>
A note on idempotents in finite AW*-factors


  We prove that the value of the quasi-trace on an idempotent element in a
AW*-factor of type II_1 is the same as the dimension of its left (or right)
support.

</DOC>
<DOC>
<DOCNO> 150836 </DOCNO>
Vacuum Energy and Casimir Force in a Presence of Skin-depth Dependent


  The vacuum energy-momentum tensor (EMT) and the vacuum energy corresponding
to massive scalar field on $\Re_{t}\times [0,l] \times \Re^{D-2}$ space-time
with boundary condition involving a dimensional parameter ($\delta$) are found.
The dependent on the cavity size $l$ Casimir energy $\wt E_{C}$ is a uniquely
determinable function of mass $m$, size $l$ and "skin-depth" $\delta$. This
energy includes the "bulk" and the surface (potential energy) contributions.
The latter dominates when $l \sim \delta$. Taking the surface potential energy
into account is crucial for the coincidence between the derivative $-\d \wt
E_{C}/\d l$ and the $ll$-component of the vacuum EMT. Casimir energy $\wt E_C$
and the bulk contribution to it are interconnected through Legendre
transformation, in which the quantity $\delta^{-1}$ is conjugate to the vacuum
surface energy multiplied by $\delta$. The surface singularities of the vacuum
EMT do not depend on $l$ and, for even $D$, $\delta =0$ or $\infty$, possess
finite interpretation. The corresponding vacuum energy is finite and retains
known analytical dependence on the dimension $D$.

</DOC>
<DOC>
<DOCNO> 67694 </DOCNO>
Analyzing epsilon'/epsilon in the 1/N_c Expansion


  We present a recent analysis of epsilon'/epsilon in the 1/N_c expansion. We
show that the 1/N_c corrections to the matrix element of Q_6 are large and
positive, indicating a Delta I=1/2 enhancement similar to the one of Q_1 and
Q_2 which dominate the CP conserving amplitude. This enhances the CP ratio and
can bring the standard model prediction close to the measured value for central
values of the parameters.

</DOC>
<DOC>
<DOCNO> 10180 </DOCNO>
Imaging the phase of an evolving Bose-Einstein condensate wavefunction


  We demonstrate a spatially resolved autocorrelation measurement with a
Bose-Einstein condensate (BEC) and measure the evolution of the spatial profile
of its quantum mechanical phase. Upon release of the BEC from the magnetic
trap, its phase develops a form that we measure to be quadratic in the spatial
coordinate. Our experiments also reveal the effects of the repulsive
interaction between two overlapping BEC wavepackets and we measure the small
momentum they impart to each other.

</DOC>
<DOC>
<DOCNO> 83174 </DOCNO>
Some Remarks on Boolean Constraint Propagation


  We study here the well-known propagation rules for Boolean constraints. First
we propose a simple notion of completeness for sets of such rules and establish
a completeness result. Then we show an equivalence in an appropriate sense
between Boolean constraint propagation and unit propagation, a form of
resolution for propositional logic.
  Subsequently we characterize one set of such rules by means of the notion of
hyper-arc consistency introduced in (Mohr and Masini 1988). Also, we clarify
the status of a similar, though different, set of rules introduced in (Simonis
1989a) and more fully in (Codognet and Diaz 1996).

</DOC>
<DOC>
<DOCNO> 101990 </DOCNO>
Finite von Neumann algebra factors with property Gamma


  Techniques introduced by G. Pisier in his proof that finite von Neumann
factors with property gamma have length at most 5 are modified to prove that
the length is 3. It is proved that if such a factor is a complemented subspace
of some larger C*-algebra then there exists a projection of norm one from the
larger onto the smaller algebra. A new proof of the fact that the second
continuous Hochschild cohomology group of such an algebra with coefficients in
the algebra vanishes, is also included.

</DOC>
<DOC>
<DOCNO> 169958 </DOCNO>
Collapse-revivals and population trapping in the m-photon mazer


  We present a study of collapse-revival patterns that appear in the changes of
atomic populations induced by the interaction of ultracold two-level atoms with
electromagnetic cavities in resonance with an $m$-photon transition of the
atoms ($m$-photon mazer). In particular, sech$^2$ and gaussian cavity mode
profiles are considered and differences in the collapse-revival patterns are
reported. The quantum theory of the $m$-photon mazer is written in the
framework of the dressed-state coordinate formalism. Simple expressions for the
atomic populations, the cavity photon statistics, and the reflection and
transmission probabilities are given for any initial state of the atom-field
system. Evidence for the population trapping phenomenon which suppress the
collapse-revivals in the $m$-photon mazer is given.

</DOC>
<DOC>
<DOCNO> 70204 </DOCNO>
Magnetic monopoles, alive


  We review recent developments in understanding the physics of the magnetic
monopoles in unbroken non-Abelian gauge theories. Since numerical data on the
monopoles are accumulated in lattice simulations, the continuum theory is
understood as the limiting case of the lattice formulation. In this review,
written for a memorial volume dedicated to the memory of Academician A.B.
Migdal, we emphasize physical effects related to the monopoles. In particular,
we discuss the monopole-antimonopole potential at short and larger distances as
well as a dual formulation of the gluodynamics, relevant to the physics of the
confinement.

</DOC>
<DOC>
<DOCNO> 117236 </DOCNO>
Threshold fragmentation under dipole forces


  The threshold law for N-body fragmentation under dipole forces is formulated.
It emerges from the energy dependence of the normalization of the correlated
continuum wave function for N fragments. It is shown that the dipole threshold
law plays a key role in understanding all threshold fragmentation phenomena
since it links the classical threshold law for long-range Coulomb interactions
to the statistical law for short-range interactions. Furthermore, a tunnelling
mechanism is identified as the common feature which occurs for all three
classes of interactions, short-range, dipole and Coulomb.

</DOC>
<DOC>
<DOCNO> 117424 </DOCNO>
Spectral Energy Distributions for Disk and Halo M--Dwarfs


  We have obtained infrared (1 to 2.5 micron) spectroscopy for 42 halo and disk
dwarfs with spectral type M1 to M6.5. These data are compared to synthetic
spectra generated by the latest model atmospheres of Allard & Hauschildt.
Photospheric parameters metallicity, effective temperature and radius are
determined for the sample. We find good agreement between observation and
theory except for known problems due to incomplete molecular data for metal
hydrides and water. The metal-poor M subdwarfs are well matched by the models
as oxide opacity sources are less important in this case. The derived effective
temperatures for the sample range from 3600K to 2600K; at these temperatures
grain formation and extinction are not significant in the photosphere. The
derived metallicities range from solar to one-tenth solar. The radii and
effective temperatures derived agree well with recent models of low mass stars.

</DOC>
<DOC>
<DOCNO> 122086 </DOCNO>
On the soft X-ray spectrum of cooling flows


  Strong evidence for cooling flows has been found in low resolution X-ray
imaging and spectra of many clusters of galaxies. However high resolution X-ray
spectra of several clusters from the Reflection Grating Spectrometer (RGS) on
XMM-Newton now show a soft X-ray spectrum inconsistent with a simple cooling
flow. The main problem is a lack of the emission lines expected from gas
cooling below 1--2 keV. Lines from gas at about 2--3 keV are observed, even in
a high temperature cluster such as A 1835, indicating that gas is cooling down
to about 2--3 keV, but is not found at lower temperatures. Here we discuss
several solutions to the problem; heating, mixing, differential absorption and
inhomogeneous metallicity. Continuous or sporadic heating creates further
problems, including the targetting of the heat at the cooler gas and also the
high total energy required. So far there is no clear observational evidence for
widespread heating, or shocks, in cluster cores, except in radio lobes which
occupy only part of the volume. The implied ages of cooling flows are short, at
about 1 Gyr. Mixing. or absorption, of the cooling gas are other possibilities.
Alternatively, if the metals in the intracluster medium are not uniformly
spread but are clumped, then little line emission is expected from the gas
cooling below 1 keV. The low metallicity part cools without line emission
whereas the strengths of the soft X-ray lines from the metal-rich gas depend on
the mass fraction of that gas and not on the abundance, since soft X-ray line
emission dominates the cooling function below 2 keV.

</DOC>
<DOC>
<DOCNO> 70021 </DOCNO>
Saturation of low-energy antiproton annihilation on nuclei


  Recent measurements of very low-energy ($p_{L}<100$ MeV/c) $\bar p$
annihilation on light nuclei reveal apparent suppression of annihilation upon
increasing the atomic charge $Z$ and mass number $A$. Using $\bar p$-nucleus
optical potentials $V_{{\rm opt}}$, fitted to $\bar p$-atom energy-shifts and
-widths, we resolve this suppression as due to the strong effective repulsion
produced by the very absorptive $V_{{\rm opt}}$. The low-energy $\bar
p$-nucleus wavefunction is kept substantially outside the nuclear surface and
the resulting reaction cross section saturates as function of the strength of
Im $V_{{\rm opt}}$. This feature, for $E >0$, parallels the recent prediction,
for $E < 0$, that the level widths of $\bar p$ atoms saturate and, hence, that
$\bar p$ deeply bound atomic states are relatively narrow. Antiproton
annihilation cross sections are calculated at $p_{L}=57$ MeV/c across the
periodic table, and their dependence on $Z$ and $A$ is classified and discussed
with respect to the Coulomb focussing effect at very low energies.

</DOC>
<DOC>
<DOCNO> 70161 </DOCNO>
Signatures of the Light Down-Squark Scenario at the Upgraded Tevatron


  In scenarios with relatively light down squarks, motivated, e.g., by SO(10) D
terms, jets + missing $E_T$ signals can be observed at the luminosity upgraded
Tevatron even if the squarks are much heavier than the gluinos and the common
gaugino mass ($M_{{1/2}}$) at $M_G$ lies above the LEP allowed lower bound. In
the conventional mSUGRA model with heavy squarks practically no signal is
expected in this channel. The possiblity of distinguishing between various
SUGRA motivated scenarios by exploiting the missing $E_T$ and jet $p_T$
distributions, opposite sign dileptons + jets + missing $E_T$ events and clean
trilepton signals have been discussed.

</DOC>
<DOC>
<DOCNO> 13213 </DOCNO>
Two models of quantum bridges connected with semiconductors or metals


  It is proposed two models describing transport and absorbtion processes that
occur in nanoscale fragments of electrical circuits, pulled adsorbed molecules,
atomic or molecular chains connecting electrodes. Discrete chain model of a
molecular bridge between metallic electrodes considers quantum jumps between
atoms containing the chain. The potential approach is represented by
three-dimensional Kronig-Penney model. The conductivity theory is developed in
a supposition that the main contribution into the electron transfer belongs to
non-equilibrium affinity populated states of the bridge. The current-voltage
and thermodynamical characteristics are calculated for different cases.
Explanations for experimentally obtained step-like dependencies in I-V
characteristics and its asymmetry are made. The charging effect and Coulomb
blockade effect are discussed. It is shown the essential role of transitions
between different bridge's charge states.

</DOC>
<DOC>
<DOCNO> 102476 </DOCNO>
Algebraic and Differential Star Products on Regular Orbits of Compact


  In this paper we study a family of algebraic deformations of regular
coadjoint orbits of compact semisimple Lie groups with the Kirillov Poisson
bracket. The deformations are restrictions of deformations on the dual of the
Lie algebra. We prove that there are non isomorphic deformations in the family.
The star products are not differential, unlike the star products considered in
other approaches. We make a comparison with the differential star product
canonically defined by Kontsevich's map.

</DOC>
<DOC>
<DOCNO> 7744 </DOCNO>
Quantum Dot Self-assembly in Growth of Strained-Layer Thin Films: a


  We use Monte-Carlo simulations to study island formation in the growth of
thin semiconducting films deposited on lattice-mismatched substrates. It is
known that islands nucleate with critical nuclei of about one atom and grow two
dimensionally until they reach a critical size s$_c$, when it is favorable for
the islands to become three dimensional.
  We investigate the mechanism for this transition from two-dimensional(2D) to
three-dimensional(3D) growth. Atoms at the edge of 2D islands with the critical
size s$_{c}$ become mobile as a result of strain and are promoted to the next
level. Edge atoms of the resulting island remain highly strained and are
promoted to the higher layers in quick succession. This process of depletion is
rapid and occurs at a sharply defined island size. We discuss why this leads to
the uniformity seen in self-assembled quantum dots in highly mismatched
heteroepitaxy

</DOC>
<DOC>
<DOCNO> 83266 </DOCNO>
Exploiting Diversity for Natural Language Parsing


  The popularity of applying machine learning methods to computational
linguistics problems has produced a large supply of trainable natural language
processing systems. Most problems of interest have an array of off-the-shelf
products or downloadable code implementing solutions using various techniques.
Where these solutions are developed independently, it is observed that their
errors tend to be independently distributed. This thesis is concerned with
approaches for capitalizing on this situation in a sample problem domain, Penn
Treebank-style parsing.
  The machine learning community provides techniques for combining outputs of
classifiers, but parser output is more structured and interdependent than
classifications. To address this discrepancy, two novel strategies for
combining parsers are used: learning to control a switch between parsers and
constructing a hybrid parse from multiple parsers' outputs.
  Off-the-shelf parsers are not developed with an intention to perform well in
a collaborative ensemble. Two techniques are presented for producing an
ensemble of parsers that collaborate. All of the ensemble members are created
using the same underlying parser induction algorithm, and the method for
producing complementary parsers is only loosely constrained by that chosen
algorithm.

</DOC>
<DOC>
<DOCNO> 120664 </DOCNO>
The Low-Mass Stars in Starburst Clusters


  If star formation depends strongly on the global properties of the
environment in which they form, the slope of the IMF as well as the upper and
lower mass cut-offs would be expected to vary significantly between violent
starbursts and more quiescent star forming regions. To test this hypothesis we
observed the stellar content of the two closest massive star forming regions,
30Doradus and NGC3603 with HST/NICMOS and VLT/ISAAC. Our observations are the
most sensitive observations made to date of dense starburst cores, allowing us
to investigate its low-mass stellar population with unprecedented quality. The
NIR luminosity function of 30Doradus shows no evidence for a truncation down to
at least 1 M_o, its stellar core R136 is populated in low-mass stars to at
least 2 M_o and NGC3603, which is very similar to R136, down to 0.1 M_o. Our
observations clearly show that low-mass stars do form in massive starbursts.

</DOC>
<DOC>
<DOCNO> 116829 </DOCNO>
Finite resolution measurement of the non-classical polarization


  By limiting the resolution of quantum measurements, the measurement induced
changes of the quantum state can be reduced, permitting subsequent measurements
of variables that do not commute with the initially measured property. It is
then possible to experimentally determine correlations between non-commuting
variables. The application of this method to the polarization statistics of
entangled photon pairs reveals that negative conditional probabilities between
non-orthogonal polarization components are responsible for the violation of
Bell's inequalities. Such negative probabilities can also be observed in finite
resolution measurements of the polarization of a single photon. The violation
of Bell's inequalities therefore originates from local properties of the
quantum statistics of single photon polarization.

</DOC>
<DOC>
<DOCNO> 174564 </DOCNO>
Observing Non-Gaussian Sources in Heavy-Ion Reactions


  We examine the possibility of extracting non-Gaussian sources from
two-particle correlations in heavy-ion reactions. Non-Gaussian sources have
been predicted in a variety of model calculations and may have been seen in
various like-meson pair correlations. As a tool for this investigation, we have
developed an improved imaging method that relies on a Basis spline expansion of
the source functions with an improved implementation of constraints. We examine
under what conditions this improved method can distinguish between Gaussian and
non-Gaussian sources. Finally, we investigate pion, kaon, and proton sources
from the p-Pb reaction at 450 GeV/nucleon and from the S-Pb reaction at 200
GeV/nucleon studied by the NA44 experiment. Both the pion and kaon sources from
the S-Pb correlations seem to exhibit a Gaussian core with an extended,
non-Gaussian halo. We also find evidence for a scaling of the source widths
with particle mass in the sources from the p-Pb reaction.

</DOC>
<DOC>
<DOCNO> 71710 </DOCNO>
Some exact solutions of the Dirac equation


  Exact analytic solutions are found to the Dirac equation for a combination of
Lorentz scalar and vector Coulombic potentials with additional non-Coulombic
parts. An appropriate linear combination of Lorentz scalar and vector
non-Coulombic potentials, with the scalar part dominating, can be chosen to
give exact analytic Dirac wave functions.

</DOC>
<DOC>
<DOCNO> 14101 </DOCNO>
Granular fingers in Hele-Shaw experiments


  Granular materials constitute an intermediate state of matter between fluids
and solids. Here we investigate the pattern formation when a grain is displaced
by another type of grain in a radial Hele-Shaw cell. We show that several
morphologies can occur, ranging from rounded to fingered patterns,
interconnected by a continuous crossover. Fourier analyses shows that, in
contrast to the rounded patterns, the fingered shapes present mode selection.

</DOC>
<DOC>
<DOCNO> 170684 </DOCNO>
Continuous loading of a magnetic trap


  We have realized a scheme for continuous loading of a magnetic trap (MT).
^{52}Cr atoms are continuously captured and cooled in a magneto-optical trap
(MOT). Optical pumping to a metastable state decouples atoms from the cooling
light. Due to their high magnetic moment (6 Bohr magnetons), low-field seeking
metastable atoms are trapped in the magnetic quadrupole field provided by the
MOT. Limited by inelastic collisions between atoms in the MOT and in the MT, we
load 10^8 metastable atoms at a rate of 10^8 atoms/s below 100 microkelvin into
the MT. After loading we can perform optical repumping to realize a MT of
ground state chromium atoms.

</DOC>
<DOC>
<DOCNO> 118740 </DOCNO>
An outline of radiatively-driven cosmology


  A Big Bang universe consisting, before recombination, of H, D, 3He, 4He, 6Li,
and 7Li ions, electrons, photons, and massless neutrinos, at closure density,
with a galaxy-size perturbation spectrum but no large-scale structure, will
evolve into the universe as we now observe it. Evolution during the first
billion years is controlled by radiation. Globular clusters are formed by
radiatively-driven implosions, galaxies are formed by radiatively triggered
gravitational collapse of systems of globular clusters, and voids are formed by
radiatively-driven expansion. After this period the strong radiation sources
are exhausted and the universe has expanded to the point where further
evolution is determined by gravity and universal expansion.

</DOC>
<DOC>
<DOCNO> 10725 </DOCNO>
\eta-superconductivity in the Hubbard chain with pair hopping


  The ground state phase diagram of the 1D Hubbard chain with pair-hopping
interaction is studied. The analysis of the model is performed using the
continuum-limit field theory approach and exact diagonalization studies. At
half-filling the phase diagram is shown to consist of two superconducting
states with Cooper pair center-of-mass momentum Q=0 (BCS-\eta_0 phase) and
Q=\pi (\eta_\pi-phase) and four insulating phases corresponding to the Mott
antiferromagnet, the Peierls dimerized phase, the charge-density-wave (CDW)
insulator as well as an unconventional insulating phase characterized by the
coexistence of a CDW and a bond-located staggered magnetization. Away from
half-filling the phase diagram consists of the superconducting BCS-\eta_0 and
\eta_\pi phases and the metallic Luttinger-liquid phase. The BCS-\eta_0 phase
exhibits smooth crossover from a weak-coupling BCS type to a strong coupling
local-pair regime. The \eta_\pi phase shows properties of the doublon (zero
size Cooper pair) superconductor with Cooper pair center-of-mass momentum
Q=\pi. The transition into the \eta_\pi- paired state corresponds to an abrupt
change in the groundstate structure. After the transition the conduction band
is completely destroyed and a new \eta_\pi-pair band corresponding to the
strongly correlated doublon motion is created.

</DOC>
<DOC>
<DOCNO> 8037 </DOCNO>
Vortex phases in condensed matter and cosmology


  Placing a high-Tc superconductor in an increasing external magnetic field,
the flux first penetrates the sample through an Abrikosov vortex lattice, and
then a first order transition is observed by which the system goes to the
normal phase. We discuss the cosmological motivation for considering the
electroweak phase transition in the presence of an external magnetic field, the
analogies this system might have with the superconductor behaviour described
above, and in particular whether at large physical Higgs masses, corresponding
to the high-Tc regime, an analogue of the vortex phase and an associated first
order phase transition could be generated.

</DOC>
<DOC>
<DOCNO> 11330 </DOCNO>
An associative memory of Hodgkin-Huxley neuron networks with


  An associative memory has been discussed of neural networks consisting of
spiking N (=100) Hodgkin-Huxley (HH) neurons with time-delayed couplings, which
memorize P patterns in their synaptic weights. In addition to excitatory
synapses whose strengths are modified after the Willshaw-type learning rule
with the 0/1 code for quiescent/active states, the network includes uniform
inhibitory synapses which are introduced to reduce cross-talk noises. Our
simulations of the HH neuron network for the noise-free state have shown to
yield a fairly good performance with the storage capacity of $\alpha_c = P_{\rm
max}/N \sim 0.4 - 2.4$ for the low neuron activity of $f \sim 0.04-0.10$. This
storage capacity of our temporal-code network is comparable to that of the
rate-code model with the Willshaw-type synapses. Our HH neuron network is
realized not to be vulnerable to the distribution of time delays in couplings.
The variability of interspace interval (ISI) of output spike trains in the
process of retrieving stored patterns is also discussed.

</DOC>
<DOC>
<DOCNO> 12815 </DOCNO>
Coherent Branched Flow in a Two-Dimensional Electron Gas


  Semiconductor nanostructures based on two dimensional electron gases (2DEGs)
have the potential to provide new approaches to sensing, information
processing, and quantum computation. Much is known about electron transport in
2DEG nanostructures and many remarkable phenomena have been discovered (e.g.
weak localization, quantum chaos, universal conductance fluctuations)1,2 - yet
a fundamental aspect of these devices, namely how electrons move through them,
has never been clarified. Important details about the actual pattern of
electron flow are not specified by statistical measures such as the mean free
path. Scanned probe microscope (SPM) measurements allow spatial investigations
of nanostructures, and it has recently become possible to directly image
electron flow through 2DEG devices using newly developed SPM techniques3-13.
Here we present SPM images of electron flow from a quantum point contact (QPC)
which show unexpected dynamical channeling - the electron flow forms
persistent, narrow, branching channels rather than smoothly spreading fans.
Theoretical study of this flow, including electron scattering by impurities and
donor atoms, shows that the channels are not due to deep valleys in the
potential, but rather are caused by the indirect cumulative effect of small
angle scattering. Surprisingly, the channels are decorated by interference
fringes well beyond where the simplest thermal averaging arguments suggest they
should be found. These findings may have important implications for 2DEG
physics and for the design of future nanostructure devices.

</DOC>
<DOC>
<DOCNO> 70774 </DOCNO>
Precision of electro--weak couplings of scalar leptoquarks at TESLA


  We investigate the potential to measure the electro-weak couplings of scalar
leptoquarks $\Phi_s$ at TESLA for energies in the range of $\sqrt{s} \simeq 1
\TeV$ using the pair production process $e^+e^- \to \Phi_s \bar{\Phi}_s$.

</DOC>
<DOC>
<DOCNO> 67762 </DOCNO>
Strategy for discovering a low-mass Higgs boson at the Fermilab Tevatron


  We have studied the potential of the CDF and DZero experiments to discover a
low-mass Standard Model Higgs boson, during Run II, via the processes
$p\bar{p}$ -> WH -> $\ell\nu b\bar{b}$, $p\bar{p}$ -> ZH ->
$\ell^{+}\ell^{-}b\bar{b}$ and $p\bar{p}$ -> ZH ->$\nu \bar{\nu} b\bar{b}$. We
show that a multivariate analysis using neural networks, that exploits all the
information contained within a set of event variables, leads to a significant
reduction, with respect to {\em any} equivalent conventional analysis, in the
integrated luminosity required to find a Standard Model Higgs boson in the mass
range 90 GeV/c**2 < M_H < 130 GeV/c**2. The luminosity reduction is sufficient
to bring the discovery of the Higgs boson within reach of the Tevatron
experiments, given the anticipated integrated luminosities of Run II, whose
scope has recently been expanded.

</DOC>
<DOC>
<DOCNO> 84781 </DOCNO>
Suspensions Thermal Noise in the LIGO Gravitational Wave Detector


  We present a calculation of the maximum sensitivity achievable by the LIGO
Gravitational wave detector in construction, due to limiting thermal noise of
its suspensions. We present a method to calculate thermal noise that allows the
prediction of the suspension thermal noise in all its 6 degrees of freedom,
from the energy dissipation due to the elasticity of the suspension wires. We
show how this approach encompasses and explains previous ways to approximate
the thermal noise limit in gravitational waver detectors. We show how this
approach can be extended to more complicated suspensions to be used in future
LIGO detectors.

</DOC>
<DOC>
<DOCNO> 151311 </DOCNO>
Non-Abelian Stokes Theorem and Computation of Wilson Loop


  It is shown that the application of the non-Abelian Stokes theorem to the
computation of the operators constructed with Wilson loop will lead to
ambiguity, if the gauge field under consideration is a non-trivial one. This
point is illustrated by the specific examples of the computation of a non-local
operator.

</DOC>
<DOC>
<DOCNO> 116275 </DOCNO>
Non equilibrium in statistical and fluid mechanics. Ensembles and their


  We present a review of the chaotic hypothesis and discuss its applications to
intermittency in statistical mechanics and fluid mechanics proposing a
quantitative definition. Entropy creation rate is interpreted in terms of
certain intermittency phenomena. An attempt to a theory of the experiment of
Ciliberto-Laroche on the fluctuation law is presented.

</DOC>
<DOC>
<DOCNO> 39692 </DOCNO>
Observation of the Decay $K_L\to \mu^+\mu^- \gamma \gamma$


  We have observed the decay $K_L\to \mu^+\mu^- \gamma \gamma$ at the KTeV
experiment at Fermilab. This decay presents a formidable background to the
search for new physics in $K_L\to\pi^0\mu^+\mu^-$. The 1997 data yielded a
sample of 4 signal events, with an expected background of 0.155 $\pm$ 0.081
events. The branching ratio is ${\mathcal B}(K_L\to \mu^+\mu^- \gamma \gamma$)
$ = (10.4^{+7.5}_{-5.9} {\rm (stat)} \pm 0.7 {\rm (sys)})\times 10^{-9}$ with
$m_{\gamma\gamma} \geq 1 {\rm MeV/c}^2$, consistent with a QED calculation
which predicts $(9.1\pm 0.8)\times 10^{-9}$.

</DOC>
<DOC>
<DOCNO> 152596 </DOCNO>
N=1 M5-brane geometries


  We describe how to construct solutions to 11-dimensional supergravity
corresponding to M5-branes wrapped on holomorphic 2-cycles embedded in C^3.
These solutions preserve N=1 supersymmetry in four dimensions. In the
near-horizon limit they are expected to be dual to N=1 large N gauge theories
in four dimensions by Maldacena's duality.

</DOC>
<DOC>
<DOCNO> 123102 </DOCNO>
Local clouds: ionization, temperatures, electron densities and


  The composition and physical properties of several local clouds, including
the Local Interstellar Cloud (LIC) in which the Sun is embedded, are derived
from absorption features in the UV spectrum of the star epsilon CMa.
  We derive temperatures and densities for three components by combining our
interpretations of the ionization balance of magnesium and the relative
population of C II in an excited fine-structure level. We find that for the LIC
n(e) = 0.12 +/-0.05 cm-3 and T = 7000 +/-1200 K.
  We derive the ionization fractions of hydrogen and discuss the ionizing
processes. In particular the hydrogen and helium ionizations in the LIC are
compatible with photoionization by the local EUV radiation fields from the hot
stars and the cloud interface with the hot gas.
  We confirm the detection of high ionization species : Si III is detected in
all clouds and C IV in two of them, including the LIC, suggesting the presence
of ionized interfaces around the local clouds.

</DOC>
<DOC>
<DOCNO> 69697 </DOCNO>
Mass dependence of HBT correlations in e^+e^- annihilation


  Mass dependence of the effective source radii, observed in hadronic $Z^0$
decays by several LEP I experiments, is analyzed in a model which assumes
proportionality between four-momentum of a produced particle and the
four-vector describing its space-time position at the freeze-out. It is shown
that this relation (commonly accepted in description of high-energy collisions)
can explain the data, provided all particles are emitted from a "tube" of $\sim
1$ fm in diameter at a constant proper time $\sim 1.5$ fm.

</DOC>
<DOC>
<DOCNO> 101128 </DOCNO>
Mirror Principle IV


  This is a continuation of "Mirror Principle III"(math.AG/9912038).

</DOC>
<DOC>
<DOCNO> 81009 </DOCNO>
A nonlocal discretization of fields


  A nonlocal method to obtain discrete classical fields is presented. This
technique relies on well-behaved matrix representations of the derivatives
constructed on a non--equispaced lattice. The drawbacks of lattice theory like
the fermion doubling or the breaking of chiral symmetry for the massless case,
are absent in this method.

</DOC>
<DOC>
<DOCNO> 12068 </DOCNO>
Bethe's equation is incomplete for the XXZ model at roots of unity


  We demonstrate for the six vertex and XXZ model parameterized by
$\Delta=-(q+q^{-1})/2\neq \pm 1$ that when q^{2N}=1 for integer $N\geq 2$ the
Bethe's ansatz equations determine only the eigenvectors which are the highest
weights of the infinite dimensional sl_2 loop algebra symmetry group of the
model. Therefore in this case the Bethe's ansatz equations are incomplete and
further conditions need to be imposed in order to completely specify the wave
function. We discuss how the evaluation parameters of the finite dimensional
representations of the sl_2 loop algebra can be used to complete this
specification.

</DOC>
<DOC>
<DOCNO> 122003 </DOCNO>
Ho from Type Ia Supernovae


  The Hubble diagrams in B, V, and I of a complete sample of 35 SNeIa with
(B-V) < 0.06 and 1200 < v < 30000 kms^{-1} have a scatter of only 0.1 mag,
after small corrections are applied for differences in decline rate Delta
m_{15} and color (B-V). The tightness of the Hubble diagrams proves blue SNeIa
to be the best ``standard candles'' known. Their absolute magnitudes M_{B,V,I}
are calibrated by eight SNeIa with Cepheid distances from HST. Combining this
calibration with the appropriate Hubble diagrams yields a large-scale value of
H_0 = 58.5+/-6.3 at the 90-percent confidence level.
   The Hubble diagram of SNeIa has so small scatter that it seems feasable to
determine Lambda ``locally'', i.e. within z<0.12, once 100-200 SNeIa with good
photometry will be available. Such a local determination would minimize
evolutionary effects and K-term corrections.

</DOC>
<DOC>
<DOCNO> 7663 </DOCNO>
Nonequilibrium Critical Phenomena and Phase Transitions into Absorbing


  This review addresses recent developments in nonequilibrium statistical
physics. Focusing on phase transitions from fluctuating phases into absorbing
states, the universality class of directed percolation is investigated in
detail. The survey gives a general introduction to various lattice models of
directed percolation and studies their scaling properties, field-theoretic
aspects, numerical techniques, as well as possible experimental realizations.
In addition, several examples of absorbing-state transitions which do not
belong to the directed percolation universality class will be discussed. As a
closely related technique, we investigate the concept of damage spreading. It
is shown that this technique is ambiguous to some extent, making it impossible
to define chaotic and regular phases in stochastic nonequilibrium systems.
Finally, we discuss various classes of depinning transitions in models for
interface growth which are related to phase transitions into absorbing states.

</DOC>
<DOC>
<DOCNO> 12326 </DOCNO>
Exact Ampitude Ratio and Finite-Size Corrections for the M x N Square


  Let f, U and C represent, respectively, the free energy, the internal energy
and the specific heat of the critical Ising model on the square M x N lattice
with periodic boundary conditions. We find that N f and U are well-defined odd
function of 1/N. We also find that ratios of subdominant (N^(-2 i - 1))
finite-size corrections amplitudes for the internal energy and the specific
heat are constant. The free energy and the internal energy at the critical
point are calculated asymtotically up to N^(-5) order, and the specific heat up
to N^(-3) order.

</DOC>
<DOC>
<DOCNO> 119593 </DOCNO>
Are There Three Peaks in the Power Spectra of GX 339-4 and Cyg X-1?


  Among the variability behaviour exhibited by neutron star systems are the
so-called ``horizontal branch oscillations'' (HBO, with frequencies ~50 Hz),
the ``lower-frequency kHz quasi-periodic oscillation'' (QPO) and the
``upper-frequency kHz QPO'', with the latter two features being separated in
frequency by an amount comparable to, but varying slightly from, the suspected
spin-frequency of the neutron star. Recently, Psaltis, Belloni, & van der Klis
(1999) have suggested that there exists a correlation between these three
frequencies that, when certain identifications of variability features are
made, even encompasses black hole sources. We consider this hypothesis by
reanalyzing a set of GX 339-4 observations. The power spectral density (PSD)
constructed from a composite of 7 separate, but very similar, observations
shows evidence for three broad peaks in the PSD. If the peak frequencies of
these features are identified with ``QPO'', then their frequencies
approximately fit the correlations suggested by Psaltis, Belloni, & van der
Klis (1999). We also reanalyze a Cyg X-1 observation and show that the
suggested QPO correlation may also hold, but that complications arise when the
``QPOs'' (which, in reality, are fairly broad features) are considered as a
function of energy band. These fits suggest the existence of at least three
separate, independent physical processes in the accretion flow, a hypothesis
that is also supported by consideration of the Fourier frequency-dependent time
lags and coherence function between variability in different energy bands.

</DOC>
<DOC>
<DOCNO> 8509 </DOCNO>
Anomalous Diffusion in Quasi One Dimensional Systems


  In order to perform quantum Hamiltonian dynamics minimizing localization
effects, we introduce a quasi-one dimensional tight-binding model whose mean
free path is smaller than the size of the sample. This one, in turn, is smaller
than the localization length. We study the return probability to the starting
layer of the system by means of direct diagonalization of the Hamiltonian. We
create a one dimensional excitation and observe sub-diffusive behavior for
times larger than the Debye time but shorter than the Heisenberg time. The
exponent corresponds to the fractal dimension $d^{*} \sim 0.72$ which is
compared to that calculated from the eigenstates by means of the inverse
participation number.

</DOC>
<DOC>
<DOCNO> 70687 </DOCNO>
Completion of standard-like embeddings


  Inequivalent standard-like observable sector embeddings in $Z_3$ orbifolds
with two discrete Wilson lines, as determined by Casas, Mondragon and Mu\~noz,
are completed by examining all possible ways of embedding the hidden sector.
The hidden sector embeddings are relevant to twisted matter in nontrivial
representations of the Standard Model and to scenarios where supersymmetry
breaking is generated in a hidden sector. We find a set of 175 models which
have a hidden sector gauge group which is viable for dynamical supersymmetry
breaking. Only four different hidden sector gauge groups are possible in these
models.

</DOC>
<DOC>
<DOCNO> 71936 </DOCNO>
The color dipole picture of the Drell-Yan process


  At high energies, Drell-Yan (DY) dilepton production viewed in the target
rest frame should be interpreted as bremsstrahlung and can be expressed in
terms of the same color dipole cross section as DIS. We compute DY cross
sections on a nucleon target with the realistic parameterization for the dipole
cross section saturated at large separations. The results are compared to
experimental data and predictions for RHIC are presented. The transverse
momentum distribution of the DY process is calculated and energy growth is
expected to be steeper at large than at small transverse momenta. We also
calculate the DY angular distribution and investigate deviations from the
1+cos^2(\theta) shape.

</DOC>
<DOC>
<DOCNO> 69699 </DOCNO>
QCD predictions for spin dependent photonic structure function


  Spin dependent structure function $g_1^{\gamma}(x,Q^2)$ of the polarised
photon is analysed within the formalism based upon the unintegrated spin
dependent parton distributions incorporating the LO Altarelli-Parisi evolution
and the double $ln^2(1/x)$ resummation at low values of Bjorken parameter x. We
analyse the effects of the double $ln^2(1/x)$ resummation on the behaviour of
$g_1^{\gamma}(x,Q^2)$ in the low x region which may be accessible in future
linear $e^+e^-$ and $e\gamma$ colliders. Sensitivity of the predictions on the
possible nonperturbative gluon content of the polarised photons is analysed.
Predictions for spin dependent gluon distribution $\Delta g^{\gamma} (x,Q^2)$
are also given.

</DOC>
<DOC>
<DOCNO> 117790 </DOCNO>
Search for Binary Protostars


  In an effort to shed more light on the formation process of binary stars, we
have started a program to study multiplicity among nearby low- and
intermediate-mass protostars using the OVRO Millimeter Array. Here, we describe
the project and present the first results on the protostellar core in the Bok
globule CB230 (L1177). At 10 arcsec resolution, the molecular core is resolved
into two components separated by 5000 AU. The morphology and kinematics of the
double core suggest that it formed from a single cloud core due to rotational
fragmentation.

</DOC>
<DOC>
<DOCNO> 13502 </DOCNO>
Griffiths effects and quantum critical points in dirty superconductors


  We introduce a strong-disorder renormalization group (RG) approach suitable
for investigating the quasiparticle excitations of disordered superconductors
in which the quasiparticle spin is not conserved. We analyze one-dimensional
models with this RG and with elementary transfer matrix methods. We find that
such models with broken spin rotation invariance {\it generically} lie in one
of two topologically distinct localized phases. Close enough to the critical
point separating the two phases, the system has a power-law divergent
low-energy density of states (with a non-universal continuously varying
power-law) in either phase, due to quantum Griffiths singularities. This
critical point belongs to the same infinite-disorder universality class as the
one dimensional particle-hole symmetric Anderson localization problem, while
the Griffiths phases in the vicinity of the transition are controlled by lines
of strong (but not infinite) disorder fixed points terminating in the critical
point.

</DOC>
<DOC>
<DOCNO> 68948 </DOCNO>
Baryonic contributions to the dilepton spectra in relativistic heavy ion


  We investigate the baryonic contributions to the dilepton yield in high
energy heavy ion collisions within the context of a transport model. The
relative contribution of the baryonic and mesonic sources are examined. It is
observed that most dominant among the baryonic channels is the decay of
N*(1520) and mostly confined in the region below the rho peak. In a transport
theory implementation we find the baryonic contribution to the lepton pair
yield to be small.

</DOC>
<DOC>
<DOCNO> 152003 </DOCNO>
Dual description of U(1) charged fields in (2+1) dimensions


  We show that the functional bosonization procedure can be generalized in such
a way that, to any field theory with a conserved Abelian charge in (2+1)
dimensions, there corresponds a dual Abelian gauge field theory. The properties
of this mapping and of the dual theory are discussed in detail, presenting
different explicit examples. In particular, the meaning and effect of the
coefficient of the Chern-Simons term in the dual action is interpreted in terms
of the spin and statistics connection.

</DOC>
<DOC>
<DOCNO> 80882 </DOCNO>
Gauge independence of Abelian and monopole dominance


  We formulate a stochastic gauge fixing method to study the gauge dependence
of Abelian projection. In this method, one can change the gauge from the
maximally Abelian one to no gauge fixing continuously. We have found that the
linear part of the heavy quark potential from Abelian contribution depends
little on the gauge parameter. Similar results have been obtained for the
monopole contribution part.We also investigate the gauge dependence of the
length of monopole loop, which is known to be important for the confinement,
and monopole density. These results suggest that the picture that monopole
plays an important role for the confinement of QCD dose not depend on choice of
the gauge.

</DOC>
<DOC>
<DOCNO> 118365 </DOCNO>
On the Role of Dust Particles in Decoupling of Plasma from Magnetic


  The objective of this paper is to apply the recent achievements in
understanding of the non-MHD effects in plasma (acquired both in laboratory
experiments, as well as in theory), to the interstellar phenomena. Applied to
the space plasma, these effects can significantly change the picture of plasma
dynamics. Charged dust particles are always present in the interstellar medium
and can easily remain not magnetized, even when the plasma electrons and ions
are strongly magnetized. In such a medium, the magnetic field can propagate
with the super-Alfven velocity. This breaks the local "frozen-in" law for the
magnetic field, which can significantly affect the gravitational collapse
phenomena, the space plasma turbulence spectrum, magnetic dynamo and the rate
of the Fermi acceleration of cosmic rays.

</DOC>
<DOC>
<DOCNO> 40409 </DOCNO>
Search for Rare and Forbidden Charm Meson Decays at Fermilab E791


  We report the results of a blind search for flavor-changing neutral current,
lepton-flavor violating, and lepton-number violating decays of D+, D(s)+, and
D0 mesons (and their antiparticles) into modes containing muons and electrons.
Using data from Fermilab charm hadroproduction experiment E791, we examine the
pi l l and K l l decay modes of D+ and D(s)+ and the l+ l- decay modes of D0.
No evidence for any of these decays is found. Therefore, we present
branching-fraction upper limits at 90% confidence level for the 24 decay modes
examined. Eight of these modes have no previously reported limits, and fourteen
are reported with significant improvements over previously published results.

</DOC>
<DOC>
<DOCNO> 151955 </DOCNO>
Symmetries of fluid dynamics with polytropic exponent


  The symmetries of the general Euler equations of fluid dynamics with
polytropic exponent are determined using the Kaluza-Klein type framework of
Duval et $\it{al}$. In the standard polytropic case the recent results of
O'Raifeartaigh and Sreedhar are confirmed and generalized. Similar results are
proved for polytropic exponent $\gamma=-1$, which corresponds to the
dimensional reduction of $d$-branes. The relation between the duality
transformation used in describing supernova explosion and Cosmology is
explained.

</DOC>
<DOC>
<DOCNO> 151965 </DOCNO>
BRST Invariance of the Non-Perturbative Vacuum in Bosonic Open String


  Tachyon condensation on a bosonic D-brane was recently demonstrated
numerically in Witten's open string field theory with level truncation
approximation. This non-perturbative vacuum, which is obtained by solving the
equation of motion, has to satisfy furthermore the requirement of BRST
invariance. This is indispensable in order for the theory around the
non-perturbative vacuum to be consistent. We carry out the numerical analysis
of the BRST invariance of the solution and find that it holds to a good
accuracy. We also mention the zero-norm property of the solution. The
observations in this paper are expected to give clues to the analytic
expression of the vacuum solution.

</DOC>
<DOC>
<DOCNO> 11399 </DOCNO>
The Evolution of Quasiparticle Charge in the Fractional Quantum Hall


  The charge of quasiparticles in a fractional quantum Hall (FQH) liquid,
tunneling through a partly reflecting constriction with transmission t, was
determined via shot noise measurements. In the nu=1/3 FQH state, a charge
smoothly evolving from e*=e/3 for t=1 to e*=e for t<<1 was determined, agreeing
with chiral Luttinger liquid theory. In the nu=2/5 FQH state the quasiparticle
charge evolves smoothly from e*=e/5 at t=1 to a maximum charge less than e*=e/3
at t<<1. Thus it appears that quasiparticles with an approximate charge e/5
pass a barrier they see as almost opaque.

</DOC>
<DOC>
<DOCNO> 10649 </DOCNO>
Transition from Abelian to non-Abelian FQHE states


  We study the transition from the Abelian multi-component (3,3,1) quantum Hall
state to the non-Abelian one component Pfaffian state in bilayer two
dimensional electron systems. We show that tunneling between layers can induce
this transition. At the transition points part of the degrees of freedom that
describe the (3,3,1) state disappear from the spectrum, and the system is
correctly described by the Pfaffian state, with quasi-particles that satisfy
non-Abelian statistics. The mechanism described in this work provides for a
physical Hamiltonian interpretation of the algebraic projection from the
(3,3,1) to the Pfaffian state that has been discussed in the literature.

</DOC>
<DOC>
<DOCNO> 100835 </DOCNO>
Lagrangian subvarieties of abelian fourfolds


  We construct examples of algebraic surfaces with interesting fundamental
groups.

</DOC>
<DOC>
<DOCNO> 8264 </DOCNO>
Thermal convection in fluidized granular systems


  Thermal convection is observed in molecular dynamic simulation of a fluidized
granular system of nearly elastic hard disks moving under gravity, inside a
rectangular box. Boundaries introduce no shearing or time dependence, but the
energy injection comes from a slip (shear-free) thermalizing base. The top wall
is perfectly elastic and lateral boundaries are either elastic or periodic. The
observed convection comes from the effect of gravity and the spontaneous
granular temperature gradient that the system dynamically develops.

</DOC>
<DOC>
<DOCNO> 80894 </DOCNO>
Heavy-light meson spectrum with and without NRQCD


  Results for the spectrum of S and P-wave charmed mesons are obtained in the
quenched approximation from a tadpole-improved anisotropic gauge field action
and a D234 quark action. This is compared to the spectrum obtained from an
NRQCD charm quark and a D234 light antiquark. NRQCD results for bottom mesons
are also discussed.

</DOC>
<DOC>
<DOCNO> 121044 </DOCNO>
Quasar-galaxy associations revisited


  Gravitational lensing predicts an enhancement of the density of bright,
distant QSOs around foreground galaxies. We measure this QSO-galaxy correlation
w_qg for two complete samples of radio-loud quasars, the southern 1Jy and
Half-Jansky samples. The existence of a positive correlation between z~1
quasars and z~0.15 galaxies is confirmed at a p=99.0% significance level
(>99.9%) if previous measurements on the northern hemisphere are included). A
comparison with the results obtained for incomplete quasar catalogs (e.g. the
Veron-Cetty and Veron compilation) suggests the existence of an `identification
bias', which spuriously increases the estimated amplitude of the quasar-galaxy
correlation for incomplete samples. This effect may explain many of the
surprisingly strong quasar-galaxy associations found in the literature.
Nevertheless, the value of w_qg that we measure in our complete catalogs is
still considerably higher than the predictions from weak lensing. We consider
two effects which could help to explain this discrepancy: galactic dust
extinction and strong lensing.

</DOC>
<DOC>
<DOCNO> 178660 </DOCNO>
A netron halo in 8He


  The structure of $^8$He is investigated within a three-cluster microscopic
model. The three-cluster configuration $\alpha+^2n+^2n$ was used to describe
the properties of the ground state of the nucleus. The obtained results
evidently indicate the existence of a neutron halo in $^8$He.

</DOC>
<DOC>
<DOCNO> 80646 </DOCNO>
Measuring the aspect ratio renormalization of anisotropic-lattice gluons


  Using tadpole inproved actions we investigate the consistency between
different methods of measuring the aspect ratio renormalization of
anisotropic-lattice gluons for bare aspect ratios \chi_0=4,6,10 and inverse
lattice spacing in the range a_s^{-1}=660-840 MeV. The tadpole corrections to
the action, which are established self-consistently, are defined for two cases,
mean link tadpoles in Landau gauge and gauge invariant mean plaquette tadpoles.
Parameters in the latter case exhibited no dependence on the spatial lattice
size, L, while in the former, parameters showed only a weak dependence on L
easily extrapolated to L=\infty.
  The renormalized anisotropy \chi_R was measured using both the torelon
dispersion relation and the sideways potential method. We found good agreement
between these different approaches. Any discrepancy was at worst 3-4% which is
consistent with the effect of lattice artifacts that for the torelon we
estimate as O(\a_Sa_s^2/R^2) where R is the flux-tube radius.
  We also present some new data that suggests that rotational invariance is
established more accurately for the mean-link action than the plaquette action.

</DOC>
<DOC>
<DOCNO> 8668 </DOCNO>
Depression of quasiparticle density of states at zero energy in


  We have measured low-temperature specific heat C(T, H) of
La1.9Sr0.1Cu1-xZnxO4 (x=0, 0.01, and 0.02) both in zero and applied magnetic
fields. A pronounced dip of C/T below 2 K was first observed in Zn-doped
samples, which is absent in the nominally clean one. If the origin of the dip
in C/T is electronic, the quasiparticle density of states N(E) in Zn-doped
samples may be depressed below a small energy scale E0. The present data can be
well described by the model N(E)=N(0)+alphaE^1/2, with a non-zero N(0) and
positive alpha. Magnetic fields depress N(0) and lead to an increase in E0,
while leaving the energy dependence of N(E) unchanged. This novel depression of
N(E) below E0 in impurity-doped cuprates can not be reconciled with the
semi-classical self-consistent approximation model. Discussions in the
framework based on the non-linear sigma model field theory and other possible
explanations are presented in this Letter.

</DOC>
<DOC>
<DOCNO> 13333 </DOCNO>
Temperature Evolution of the Quantum Gap in CsNiCl3


  Neutron scattering measurements on the one-dimensional gapped S=1
antiferromagnet, CsNiCl3, have shown that the excitation corresponding to the
Haldane mass gap Delta at low temperatures persists as a resonant feature to
high temperatures. We find that the strong upward renormalisation of the gap
excitation, by a factor of three between 5 and 70K, is more than enough to
overcome its decreasing lifetime. We find that the gap lifetime is
substantially shorter than that predicted by the scaling theory of Damle and
Sachdev in its low temperature range of validity. The upward gap
renormalisation agrees with the non-linear sigma model at low temperatures and
even up to T of order 2Delta provided an upper mass cutoff is included.

</DOC>
<DOC>
<DOCNO> 100422 </DOCNO>
Uniform ergodic theorems on subshifts over a finite alphabet


  We investigate uniform ergodic type theorems for additive and subadditive
functions on a subshift over a finite alphabet. We show that every strictly
ergodic subshift admits a uniform ergodic theorem for Banach-space-valued
additive functions. We then give a necessary and sufficient condition on a
minimal subshift to allow for a uniform subadditive ergodic theorem. This
provides in particular a sufficient condition for unique ergodicity.

</DOC>
<DOC>
<DOCNO> 118400 </DOCNO>
A correction to the pp reaction


  These descriptive comments are made to encourage detailed three-body,
relativistic, quantum collision calculations for the pp reaction. In stars,
coulomb barrier tunneling, as in the pp reaction, is not a two-body process.
Tunneling is mediated by an energetic electron that interacts with the
colliding particles. The presence of such an electron lowers the potential
barrier and increases the probability of tunneling by orders of magnitude. The
solar luminosity can be maintained with a central temperature near 10 million K
where the neutrino production rates correspond to the observed rates. Current
stellar interior and evolutionary models need substantial revision.

</DOC>
<DOC>
<DOCNO> 119747 </DOCNO>
Pair Plasma Dominance in the Parsec-Scale Relativistic Jet of 3C345


  We investigate whether a pc-scale jet of 3C345 is dominated by a normal
plasma or an electron-positron plasma. We present a general condition that a
jet component becomes optically thick for synchrotron self-absorption, by
extending the method originally developed by Reynolds et al. The general
condition gives a lower limit of the electron number density, with the aid of
the surface brightness condition, which enables us to compute the magnetic
field density. Comparing the lower limit with another independent constraint
for the electron density that is deduced from the kinetic luminosity, we can
distinguish the matter content. We apply the procedure to the five components
of 3C345 (C2, C3, C4, C5, and C7) of which angular diameters and radio fluxes
at the peak frequencies were obtainable from literature. Evaluating the
representative values of Doppler beaming factors by their equipartition values,
we find that all the five components are likely dominated by an
electron-positron plasma. The conclusion does not depend on the lower cutoff
energy of the power-law distribution of radiating particles.

</DOC>
<DOC>
<DOCNO> 68928 </DOCNO>
Cosmic Tau Neutrinos


  The collisions between accelerated protons and the photons present in cosmos
can be a main source of high-energy neutrinos (E \geq 10^6 GeV) of all flavors
above the atmospheric neutrino background. I discuss here the possibility of
photohadronic production of high-energy cosmic tau neutrinos in an
astrophysical site and study some of the effects of vacuum neutrino flavor
mixing on their subsequent propagation. I also discuss the prospects for
observations of these high-energy cosmic tau neutrinos in new large neutrino
telescopes

</DOC>
<DOC>
<DOCNO> 83365 </DOCNO>
Lexicalized Stochastic Modeling of Constraint-Based Grammars using


  We present a new approach to stochastic modeling of constraint-based grammars
that is based on log-linear models and uses EM for estimation from unannotated
data. The techniques are applied to an LFG grammar for German. Evaluation on an
exact match task yields 86% precision for an ambiguity rate of 5.4, and 90%
precision on a subcat frame match for an ambiguity rate of 25. Experimental
comparison to training from a parsebank shows a 10% gain from EM training.
Also, a new class-based grammar lexicalization is presented, showing a 10% gain
over unlexicalized models.

</DOC>
<DOC>
<DOCNO> 122712 </DOCNO>
XMM-Newton EPIC and RGS observations of LMC X-3


  We report the results of preliminary analysis of the XMM_Newton EPIC and RGS
observations of the candidate black-hole binary LMC X-3 between February and
June 2000. The observations covered both the soft and the hard X-ray spectral
states. The hard-state spectra were dominated by a power-law component with a
photon index Gamma = 1.9 +/- 0.1. The soft-state spectra consisted of a thermal
component with a multi-colour disk temperature T_in = 0.9 keV and a power-law
tail with Gamma ~ 2.5--2.7. The model in which the X-rays from LMC X-3 in the
high-soft state are powered by a strong stellar wind from a massive companion
is not supported by the small line-of-sight absorption (n_H <~ 10^{21} cm^{-2})
deduced from the RGS data. The transition from the soft to the hard state
appears to be a continuous process associated with the changes in the
mass-transfer rate.

</DOC>
<DOC>
<DOCNO> 151432 </DOCNO>
Supergravity and Space-Time Non-Commutative Open String Theory


  We study the non-critical space-time non-commutative open string (NCOS)
theory using a dual supergravity description in terms of a certain near-horizon
limit of the F1-Dp bound state. We find the thermodynamics of NCOS theory from
supergravity. The thermodynamics is equivalent to Yang-Mills theory on a
commutative space-time. We argue that this fact does not have to be in
contradiction with the expected Hagedorn behaviour of NCOS theory. To support
this we consider string corrections to the thermodynamics. We also discuss the
relation to Little String Theory in 6 dimensions.

</DOC>
<DOC>
<DOCNO> 80748 </DOCNO>
Percolation and Deconfinement in SU(2) Gauge Theory


  The deconfinement transition in SU(2) gauge theory and the magnetization
transition in the Ising model belong to the same universality class. The
critical behaviour of the Ising model can be characterized either as
spontaneous breaking of the $Z_2$ symmetry of spin states or as percolation of
appropriately defined spin clusters. We show that deconfinement in SU(2) gauge
theory can be specified as percolation of Polyakov loop clusters with
Fortuin-Kasteleyn bond weights, leading to the same critical exponents as the
conventional order-disorder description based on the Polykov loop expectation
value.

</DOC>
<DOC>
<DOCNO> 9729 </DOCNO>
Confinement Effects in Antiferromagnets


  Phase equilibrium in confined Ising antiferromagnets was studied as a
function of the coupling (v) and a magnetic field (h) at the surfaces, in the
presence of an external field H. The ground state properties were calculated
exactly for symmetric boundary conditions and nearest-neighbor interactions,
and a full zero-temperature phase diagram in the plane v-h was obtained for
films with symmetry-preserving surface orientations. The ground-state analysis
was extended to the H-T plane using a cluster-variation free energy. The study
of the finite-T properties (as a function of v and h) reveals the close
interdependence between the surface and finite-size effects and, together with
the ground-state phase diagram, provides an integral picture of the confinement
in anisotropic antiferromagnets with surfaces that preserve the symmetry of the
order parameter.

</DOC>
<DOC>
<DOCNO> 10461 </DOCNO>
Stability of the monoclinic phase in the ferroelectric perovskite


  Recent structural studies of ferroelectric PbZr(1-x)TixO3 (PZT) with x= 0.48,
have revealed a new monoclinic phase in the vicinity of the morphotropic phase
boundary (MPB), previously regarded as the the boundary separating the
rhombohedral and tetragonal regions of the PZT phase diagram. In the present
paper, the stability region of all three phases has been established from high
resolution synchrotron x-ray powder diffraction measurements on a series of
highly homogeneous samples with 0.42 <=x<= 0.52. At 20K the monoclinic phase is
stable in the range 0.46 <=x<= 0.51, and this range narrows as the temperature
is increased. A first-order phase transition from tetragonal to rhombohedral
symmetry is observed only for x= 0.45. The MPB, therefore, corresponds not to
the tetragonal-rhombohedral phase boundary, but instead to the boundary between
the tetragonal and monoclinic phases for 0.46 <=x<= 0.51. This result provides
important insight into the close relationship between the monoclinic phase and
the striking piezoelectric properties of PZT; in particular, investigations of
poled samples have shown that the monoclinic distortion is the origin of the
unusually high piezoelectric response of PZT.

</DOC>
<DOC>
<DOCNO> 170507 </DOCNO>
Approximate quantum cloning and the impossibility of superluminal


  We show that nonlocality of quantum mechanics cannot lead to superluminal
transmission of information, even if most general local operations are allowed,
as long as they are linear and trace preserving. In particular, any quantum
mechanical approximate cloning transformation does not allow signalling. On the
other hand, the no-signalling constraint on its own is not sufficient to
prevent a transformation from surpassing the known cloning bounds. We
illustrate these concepts on the basis of some examples.

</DOC>
<DOC>
<DOCNO> 179049 </DOCNO>
p-Shell Nuclei and Two-Frequency Shell Model with a Realistic Effective


  We have studied p-shell nuclei using a two-frequency shell-model approach
with an effective interaction derived from the Bonn-A nucleon-nucleon potential
by means of a G-matrix folded-diagram method. First, we briefly describe our
derivation of the effective interaction in a model space composed of harmonic
hoscillator wave functions with two different length parameters, b_in and
b_out, for the core and the valence orbits, respectively. Then we present some
selected results of our calculations. We show that a good agreement with
experiment is obtained, which is definitely better than that provided by a
standard one-frequency calculation. A comparison with results obtained from
large-basis shell-model calculations is also made.

</DOC>
<DOC>
<DOCNO> 101334 </DOCNO>
The Appell hypergeometric functions and classical separable mechanical


  A relationship between two old mathematical subjects is observed: the theory
of hypergeometric functions and the separability in classical mechanics.
Separable potential perturbations of the integrable billiard systems and the
Jacobi problem for geodesics on an ellipsoid are expressed through the Appell
hypergeometric functions $F_4$ of two variables. Even when the number of
degrees of freedom increases, if an ellipsoid is symmetric, the number of
variables in the hypergeometric functions does not. Wider classes of separable
potentials are given by the obtained new formulae automaticaly.

</DOC>
<DOC>
<DOCNO> 116536 </DOCNO>
Elementary Nonrelativistic Quantum Mechanics


  This is a graduate course on elementary quantum mechanics written for the
benefit of undergraduate and graduate students. It is the English version of
physics/0003106, which I did at the suggestion of several students from
different countries. The topics included refer to the postulates of quantum
mechanics, one-dimensional barriers and wells, angular momentum and spin, WKB
method, harmonic oscillator, hydrogen atom, quantum scattering, and partial
waves

</DOC>
<DOC>
<DOCNO> 101933 </DOCNO>
An Efficient Modified "Walk On Spheres" Algorithm for the Linearized


  A discrete random walk method on grids was proposed and used to solve the
linearized Poisson-Boltzmann equation (LPBE) \cite{Rammile}. Here, we present a
new and efficient grid-free random walk method. Based on a modified `` Walk On
Spheres" (WOS) algorithm \cite{Elepov-Mihailov1973} for the LPBE, this Monte
Carlo algorithm uses a survival probability distribution function for the
random walker in a continuous and free diffusion region. The new simulation
method is illustrated by computing four analytically solvable problems. In all
cases, excellent agreement is observed.

</DOC>
<DOC>
<DOCNO> 40669 </DOCNO>
SUSY Long-Lived Massive Particles: Detection and Physics at the LHC


  We draw a possible scenario for the observation of massive long-lived charged
particles at the LHC detector ATLAS. The required flexibility of the detector
triggers and of the identification and reconstruction systems are discussed. As
an example, we focus on the measurement of the mass and lifetime of long-lived
charged sleptons predicted in the framework of supersymmetric models with
gauge-mediated supersymmetry (SUSY) breaking. In this case, the
next-to-lightest SUSY particle can be the light scalar partner of the tau
lepton, possibly decaying slowly into a gravitino. A wide region of the SUSY
parameters space was explored. The accessible range and precision on the
measurement of the SUSY breaking scale parameter sqrt(F) achievable with a
counting method are assessed.

</DOC>
<DOC>
<DOCNO> 101306 </DOCNO>
Maximal Unipotent Monodromy for Complete Intersection CY Manifolds


  The computations that are suggested by String Theory in the B model requires
the existence of degenerations of CY manifolds with maximum unipotent
monodromy. In String Theory such a point in the moduli space is called a large
radius limit (or large complex structure limit). In this paper we are going to
construct one parameter families of $n$ dimensional Calabi-Yau manifolds, which
are complete intersections in toric varieties and which have a monodromy
operator $T$ such that (T$^{N}-id)^{n+1}=0$ but (T$^{N}-id)^{n}\neq0,$ i.e the
monodromy operator is maximal unipotent.

</DOC>
<DOC>
<DOCNO> 100258 </DOCNO>
A New Geometric Probability Technique for an N-dimensional Sphere and


  A new formalism is presented for analytically obtaining the probability
density function, \( P_{n}(s) \), for the distance between two random points in
an \( n \)-dimensional sphere of radius \( R \). Our formalism allows \(
P_{n}(s) \) to be calculated for a sphere having an arbitrary density
distribution, and reproduces the well-known results for the case of a sphere
with uniform density. The results find applications in stochastic geometry,
probability distribution theory, astrophysics, nuclear physics, and elementary
particle physics.

</DOC>
<DOC>
<DOCNO> 118993 </DOCNO>
Linear Redshift Distortions and Power in the PSCz Survey


  We present a state-of-the-art linear redshift distortion analysis of the
recently published IRAS Point Source Catalog Redshift Survey (PSCz). The
procedure involves linear compression into 4096 Karhunen-Loeve modes culled
from a potential pool of about 3 x 10^5 modes, followed by quadratic
compression into three separate power spectra, the galaxy-galaxy,
galaxy-velocity, and velocity-velocity power spectra. Least squares fitting to
the decorrelated power spectra yields a linear redshift distortion parameter
beta = Omega_m^0.6/b = 0.41(+0.13,-0.12).

</DOC>
<DOC>
<DOCNO> 80749 </DOCNO>
Large N limit of the IKKT matrix model


  Using the dynamical triangulation approach we perform a numerical study of a
supersymmetric random surface model that corresponds to the large N limit of
the four-dimensional version of the IKKT matrix model. We show that the
addition of fermionic degrees of freedom suppresses the spiky world-sheet
configurations that are responsible for the pathological behaviour of the
purely bosonic model. We observe that the distribution of the gyration radius
has a power-like tail p(R) ~ R^{-2.4}. We check numerically that when the
number of fermionic degrees of freedom is not susy-balanced, p(R) grows with
$R$ and the model is not well-defined. Numerical sampling of the configurations
in the tail of the distribution shows that the bosonic degrees of freedom
collapse to a one-dimensional tube with small transverse fluctuations. Assuming
that the vertex positions can fluctuate independently within the tube, we give
a theoretical argument which essentially explains the behaviour of p(R) in the
different cases, in particular predicting p(R) ~ R^{-3} in the supersymmetric
case. Extending the argument to six and ten dimensions, we predict p(R) ~
R^{-7} and p(R) ~ R^{-15}, respectively.

</DOC>
<DOC>
<DOCNO> 178649 </DOCNO>
Analysis of the low-energy $\eta$NN-dynamics within a three-body


  The interaction of an $\eta$-meson with two nucleons is studied within a
three-body approach. The major features of the $\eta NN$-system in the
low-energy region are accounted for by using a s-wave separable ansatz for the
two-body $\eta N$- and $NN$-amplitudes. The calculation is confined to the
$(J^\pi;T)=(0^-;1)$ and $(1^-;0)$ configurations which are assumed to be the
most promising candidates for virtual or resonant $\eta NN$-states. The
eigenvalue three-body equation is continued analytically into the nonphysical
sheets by contour deformation. The position of the poles of the three-body
scattering matrix as a function of the $\eta N$-interaction strength is
investigated. The corresponding trajectory, starting on the physical sheet,
moves around the $\eta NN$ three-body threshold and continues away from the
physical area giving rise to virtual $\eta NN$-states. The search for poles on
the nonphysical sheets adjacent directly to the upper rim of the real energy
axis gives a negative result. Thus no low-lying s-wave $\eta NN$-resonances
were found. The possible influence of virtual poles on the low-energy $\eta
NN$-scattering is discussed.

</DOC>
<DOC>
<DOCNO> 152604 </DOCNO>
Radion Stabilization by Brane Matter


  We find a static solution to Einstein's field equations on a five-dimensional
orbifold with a compact S_1/Z_2 fifth direction and Poincare invariant 3+1
sections. The solution describes a theory with bulk cosmological constant and
3-branes at the orbifold fixed points which carry matter density and pressure
in addition to tension. The radius of the fifth dimension is determined by the
matter content of the branes. The ratio of the space and time components of the
metric depends on the fifth coordinate. Thus, the speed of propagation of
massless fields is path dependent. For example, bulk and brane fields propagate
with different speeds.

</DOC>
<DOC>
<DOCNO> 116445 </DOCNO>
A waveguide atom beamsplitter for laser-cooled neutral atoms


  A laser-cooled neutral-atom beam from a low-velocity intense source is split
into two beams while guided by a magnetic-field potential. We generate our
multimode-beamsplitter potential with two current-carrying wires on a glass
substrate combined with an external transverse bias field. The atoms bend
around several curves over a $10$-cm distance. A maximum integrated flux of
$1.5\cdot10^{5} \mathrm{atoms/s}$ is achieved with a current density of
$5\cdot10^{4} \mathrm{Ampere/cm^{2}}$ in the 100-$\mathrm{\mu m}$ diameter
wires. The initial beam can be split into two beams with a 50/50 splitting
ratio.

</DOC>
<DOC>
<DOCNO> 72266 </DOCNO>
Excitations of Rotational States in String Model of Meson and in


  For the relativistic string with massive ends, the three-string baryon model
and other string models of the baryon the small disturbances of well known
rotational motions are considered. For the string meson model the two types of
these disturbances (quasirotational motions) are obtained. They are oscillatory
motions in the form of stationary waves in the rotational plane and in the
orthogonal direction. These solutions may be used for describing more wide
spectrum of hadron excitations and for the quantization of this nonlinear
system. For three-string baryon model or Y configuration these quasirotational
motions are more complicated and contain the branch with growing amplitudes.
This consideration proves that for the three-string model with both massless
and massive ends the rotational motions are unstable on the classical level.

</DOC>
<DOC>
<DOCNO> 119549 </DOCNO>
Early Starbursts and Magnetic Field Generation in Galaxy Clusters


  We propose a mechanism for the early generation of the mean Intracluster
magnetic field in terms of magnetized galactic winds. These winds are the
result of starburst phases of the cluster galaxies, assumed to produce the
predominant population of early type galaxies in mergers of gas-rich
progenitors. After further cluster contraction typical field strengths are
$10^{-7}$ Gauss. This estimate may increase to the level of $10^{-6}$ Gauss if
more extreme galactic parameters, and subsequent shear amplification of the
field are considered. The topology of the field is one of almost unconnected
Wind Bubbles with Parker-type spiral field configurations over scales of the
distance between galaxies. Further cluster accretion, that continues
chaotically in space and time up to the present, will perturb these
"large-scale" mean fields on smaller or at best comparable spatial scales. The
small scale fields in the resulting turbulent fluctuation spectrum should be
able to confine relativistic particles over times longer than the age of the
Universe. The nonthermal particle content of galaxy clusters should therefore
also have a "cosmological" hadronic component generated during the early
starburst phase of the member galaxies. Already by itself it implies a
nonthermal energy fraction of about 10 percent for the Intracluster gas which
should then be detectable by future gamma-ray telescopes.

</DOC>
<DOC>
<DOCNO> 12014 </DOCNO>
Monte Carlo Simulations of the Random-Field Ising Model


  Ising Monte Carlo simulations of the random-field Ising system
Fe(0.80)Zn(0.20)F2 are presented for H=10T. The specific heat critical behavior
is consistent with alpha approximately 0 and the staggered magnetization with
beta approximately 0.25 +- 0.03.

</DOC>
<DOC>
<DOCNO> 118259 </DOCNO>
Extragalactic Results from the Infrared Space Observatory


  More than a decade ago the IRAS satellite opened the realm of external
galaxies for studies in the 10 to 100 micron band and discovered emission from
tens of thousands of normal and active galaxies. With the 1995-1998 mission of
the Infrared Space Observatory the next major steps in extragalactic infrared
astronomy became possible: detailed imaging, spectroscopy and
spectro-photometry of many galaxies detected by IRAS, as well as deep surveys
in the mid- and far- IR. The spectroscopic data reveal a wealth of detail about
the nature of the energy source(s) and about the physical conditions in
galaxies. ISO's surveys for the first time explore the infrared emission of
distant, high-redshift galaxies. ISO's main theme in extragalactic astronomy is
the role of star formation in the activity and evolution of galaxies.

</DOC>
<DOC>
<DOCNO> 14030 </DOCNO>
Magneto-Elastic Coupling in the Layered Manganite


  We have studied the magneto-elastic coupling in the double layered Mn
perovskite La$_{1.2}$Sr$_{1.8}$Mn$_2$O$_7$ with an ultrasonic velocity
technique. The temperature profile of both the in-plane and out-of-plane
longitudinal velocities showed a large stiffening anomaly below the insulating
paramagnetic to metallic ferromagnetic transition. Magnetic fluctuations
effects consistent with the layered structure are evidenced as a frequency
dependent velocity softening above the transition. The magneto-elastic coupling
has been studied in magnetic field values up to 8 Tesla: the observations are
consistent with a substantial magnetic anisotropy and a ferromagnetic order
parameter with moments lying in the layers.

</DOC>
<DOC>
<DOCNO> 11043 </DOCNO>
Optimization of Trading Physics Models of Markets


  We describe an end-to-end real-time S&P futures trading system. Inner-shell
stochastic nonlinear dynamic models are developed, and Canonical Momenta
Indicators (CMI) are derived from a fitted Lagrangian used by outer-shell
trading models dependent on these indicators. Recursive and adaptive
optimization using Adaptive Simulated Annealing (ASA) is used for fitting
parameters shared across these shells of dynamic and trading models.

</DOC>
<DOC>
<DOCNO> 70080 </DOCNO>
Entropy in hadron-hadron collisions


  We analyse the entropy properties in the proton-proton 1800 GeV events from
the PYTHIA/JETSET Monte Carlo generator following a recent proposal concerning
the measurement of entropy in multiparticle systems. The dependence on the
number of bins and on the size of the phase-space region is investigated. Our
results may serve as a reference sample for experimental data from
hadron-hadron and heavy ion collisions.

</DOC>
<DOC>
<DOCNO> 120639 </DOCNO>
Mapping the star formation history of Mrk86: II. Stellar populations and


  In this paper, continuation of Gil de Paz et al. (Paper I), we derive the
main properties of the stellar populations in the Blue Compact Dwarf galaxy
Mrk86. Ages, stellar masses, metallicites and burst strengths have been
obtained using the combination of Monte Carlo simulations, a maximum likelihood
estimator and Cluster and Principal Component Analysis. The three stellar
populations detected show well defined properties. We have studied the
underlying stellar population, which shows an age between 5-13 Gyr and no
significant color gradients. The intermediate aged (30 Myr old) central
starburst show a very low dust extinction with high burst strength and high
stellar mass content (9 10^6 M_sun). Finally, the properties of 46
low-metallicity star-forming regions were also studied. The properties derived
suggest that the most recent star-forming activity in Mrk86 was triggered by
the evolution of a superbubble originated at the central starburst by the
energy deposition of stellar winds and supernova explosions. Finally, different
mechanisms for the star formation triggering in this massive central starburst
are studied, including the merging with a low mass companion and the
interaction with UGC4278.

</DOC>
<DOC>
<DOCNO> 7932 </DOCNO>
Statistics of Turbulence from Spectral-Line Data Cubes


  Emission in spectral lines can provide unique information on interstellar
turbulence. Doppler shifts due to supersonic motions contain information on
turbulent velocity field which is otherwise difficult to measure. However, the
problem of separation of velocity and density fluctuations is far from being
trivial. Using atomic hydrogen (HI) as a test case, I review techniques
applicable to emission line studies with the emphasis on those that can provide
information on the underlying power spectra of velocity and density. I show
that recently developed mathematical machinery is promising for the purpose.
Its application to HI shows that in cold neutral hydrogen the velocity
fluctuations dominate the small scale structures observed in spectral-line data
cubes and this result is very important for the interpretation of observational
data, including the identification of clouds. Velocity fluctuations are shown
to dominate the formation of small scale structures that can be erroneously
identified as diffuse clouds. One may argue that the HI data is consistent with
the Goldreich-Shridhar picture of magnetohydrodynamic turbulence, but the
cascade from the scales of several kpc that this interpretation involves does
not fit well in the current paradigm of energy injection. The issue whether
magnetic field does make the turbulence anisotropic is still open, but if this
is the case, I show that studies of emission lines can provide a reliable way
of determining magnetic field direction. I discuss various techniques for
studying interstellar turbulence using emission lines, e.g. spectral
correlation functions, genus statistics and principal component analysis.

</DOC>
<DOC>
<DOCNO> 152071 </DOCNO>
Relative Topological Integrals and Relative Cheeger-Simons Differential


  Topological integrals appear frequently in Lagrangian field theories. On
manifolds without boundary, they can be treated in the framework of ordinary
(co)homology using the formalism of Cheeger-Simons differential characters.
String and D-brane theory involve field theoretic models on worldvolumes with
border. On manifolds with boundary, the proper treatment of topological
integrals requires a generalization of the usual differential topological set
up and leads naturally to relative (co)homology and relative Cheeger-Simons
differential characters. In this paper, we present a construction of relative
Cheeger-Simons differential characters which is computable in principle and
which contains the ordinary Cheeger-Simons differential characters as a
particular case.

</DOC>
<DOC>
<DOCNO> 120080 </DOCNO>
What do the UV Spectra of Narrow-line Seyfert 1 Galaxies tell us about


  We study the UV spectra of narrow-line Seyfert~1 (NLSy1) galaxies and compare
them with ``normal'' AGN. Similar to their optical lines, the NLSy1s show
narrower UV lines. They are also characterized by weaker CIV 1549, CIII] 1909,
and stronger AlIII 1857 emission. These UV line properties add to the optical
and X-ray properties known to be part of the Boroson and Green eigenvector 1.
We show that the steep soft-X-rays, which characterize the NLSy1s SEDs, change
the equilibrium of the two phase cloud-intercloud medium resulting in somewhat
higher BLR cloud densities, lower ionization parameter and larger BLR radii.
These modified conditions can explain the unusual emission line properties we
find in NLSy1.
  Using a specific model of an accretion disk with corona presented by Witt,
Czerny and Zycki (1997), we also show that the steep soft and hard-X-ray
continua can be explained if the $L/L_{Edd}$ ratios are larger than in
``normal'' Seyfert1/QSO strengthening earlier suggestions that the $L/L_{Edd}$
is the physical parameter driving this eigenvector.

</DOC>
<DOC>
<DOCNO> 99952 </DOCNO>
Motivic torsors


  The torsor P_s=Hom(H_{\DR},H_s) under the motivic Galois group G_s=Aut H_s of
the Tannakian category M_k generated by one-motives related by absolute Hodge
cycles over a field k with an embedding s into the complex numbers is shown to
be determined by its global projection [P_s\to (P_s)/(G_s)^0] to a Gal(\ov
k/k)-torsor, and by its localizations (P_s) x_k (k_\xi) at a dense subset of
orderings \xi of the field k, provided k has virtual cohomological dimension
(vcd) one. This result is an application of a recent local-global principle for
connected linear algebraic groups over a field k of vcd=1.

</DOC>
<DOC>
<DOCNO> 67915 </DOCNO>
On Electroweak Baryogenesis in Gauge Mediated Models with


  We consider feasibility of electroweak baryogenesis in gauge mediated
supersymmetry breaking models with messenger-matter mixing. We present a class
of models where electroweak baryogenesis produces sufficient amount of baryon
asymmetry. The main features of these models are ({\it i}) large mixing between
messengers and right stop and ({\it ii}) fairly narrow region of viable
$\tan\beta$.

</DOC>
<DOC>
<DOCNO> 67781 </DOCNO>
Dynamics of Supersymmetric SU(n_c) and USp(2n_c) Gauge Theories


  We study dynamical flavor symmetry breaking in the context of a class of N=1
supersymmetric SU(n_c) and USp(2 n_c) gauge theories, constructed from the
exactly solvable N=2 theories by perturbing them with small adjoint and generic
bare hypermultiplet (quark) masses. We find that the flavor U(n_{f}) symmetry
in SU(n_{c}) theories is dynamically broken to $U(r)\times U(n_{f}-r)$ groups
for $n_f \leq n_c$. In the r=1 case the dynamical symmetry breaking is caused
by the condensation of monopoles in the $\underline{n_{f}}$ representation. For
general r, however, the monopoles in the $\underline{{}_{n_{f}}C_{r}}$
representation, whose condensation could explain the flavor symmetry breaking
but would produce too-many Nambu--Goldstone multiplets, actually ``break up''
into ``magnetic quarks'' which condense and induce confinement and the symmetry
breaking. In USp(2n_c) theories with $n_f \leq n_c + 1$, the flavor SO(2n_f)
symmetry is dynamically broken to U(n_f), but with no description in terms of a
weakly coupled local field theory. In both SU(n_c) and USp(2 n_c) theories,
with larger numbers of quark flavors, besides the vacua with these properties,
there exist also vacua with no flavor symmetry breaking.

</DOC>
<DOC>
<DOCNO> 8549 </DOCNO>
Ferroelectricity and structure of BaTiO3 grown on YBa2Cu3O7-d thin films


  We have investigated the crystal structure and the ferroelectric properties
of BaTiO3 thin films with YBa2Cu3O7-d as the bottom and Au as the top
electrode. Epitaxial heterostructures of YBa2Cu3O7-d and BaTiO3 were prepared
by dc and rf sputtering, respectively. The crystal structure of the films was
characterised by x-ray diffraction. The ferroelectric behaviour of the BaTiO3
films was confirmed by hysteresis loop measurements using a Sawyer Tower
circuit. We obtain a coercive field of 30 kV/cm and a remanent polarisation of
1.25 \muC/cm. At sub-switching fields the capacitance of the films obeys a
relation analogous to the Rayleigh law. This behaviour indicates an interaction
of domain walls with randomly distributed pinning centres. At a field of 5 MV/m
we calculate 3% contribution of irreversible domain wall motion to the total
dielectric constant.

</DOC>
<DOC>
<DOCNO> 71144 </DOCNO>
Comment on New Results for the Charged Pion Electromagnetic Form Factor


  In the paper nucl-ex/0010009 by The Jefferson Lab F_pi Collaboration the new
results for the charged pion electromagnetic form factor are presented. The
approach given in our paper hep-ph/9811318, "On a possible estimation of the
constituent--quark parameters from Jefferson Lab experiments on the pion form
factor" makes it possible to estimate the mass of constituent quark from such
kind of experiment. Now this estimation gives M=0.21 GeV.

</DOC>
<DOC>
<DOCNO> 122414 </DOCNO>
The Metallicity Evolution of Damped Lyman-alpha Systems


  According to Pei, Fall & Hauser (1999), the global metallicity evolution of
the Universe can be represented by the ratio of the total metal content to the
total gas content measured in Damped Lyman-alpha (DLA) systems (the ``column
density weighted metallicity'' `a la Pettini). To minimize dust obscuration
effects, a DLA sample with negligible dust content is considered, namely, 50
DLAs with log N(HI) < 20.8. The global metallicity found shows clear evidence
of redshift evolution that goes from \sim1/30 solar at z\sim4.1 to solar at z
\sim 0.4. More generally, DLAs with measured heavy elements probe the ISM of
high redshift galaxies. The whole sample collected from the literature contains
75 DLAs. The metallicity is calculated adopting for the dust correction the
most general method used so far, based on models of the ISM dust depletions in
the Galaxy. The intrinsic metallicity evolution of DLA galaxies is dlog
Z(DLA)/dz \propto -0.33 +/- 0.06.

</DOC>
<DOC>
<DOCNO> 84710 </DOCNO>
Constant Crunch Coordinates for Black Hole Simulations


  We reinvestigate the utility of time-independent constant mean curvature
foliations for the numerical simulation of a single spherically-symmetric black
hole. Each spacelike hypersurface of such a foliation is endowed with the same
constant value of the trace of the extrinsic curvature tensor, $K$. Of the
three families of $K$-constant surfaces possible (classified according to their
asymptotic behaviors), we single out a sub-family of singularity-avoiding
surfaces that may be particularly useful, and provide an analytic expression
for the closest approach such surfaces make to the singularity. We then utilize
a non-zero shift to yield families of $K$-constant surfaces which (1) avoid the
black hole singularity, and thus the need to excise the singularity, (2) are
asymptotically null, aiding in gravity wave extraction, (3) cover the
physically relevant part of the spacetime, (4) are well behaved (regular)
across the horizon, and (5) are static under evolution, and therefore have no
``grid stretching/sucking'' pathologies. Preliminary numerical runs demonstrate
that we can stably evolve a single spherically-symmetric static black hole
using this foliation. We wish to emphasize that this coordinatization produces
$K$-constant surfaces for a single black hole spacetime that are regular,
static and stable throughout their evolution.

</DOC>
<DOC>
<DOCNO> 169632 </DOCNO>
Pulse propagation in three-level medium


  We investigate propagation of a pulse pair in a three-level medium under the
adiabatic following condition for the general case of unequal oscillator
strengths. Exact analytical solutions to the propagation equations have been
obtained. It is shown that propagation dynamics strongly depends on the
relationship between oscillator strengths. The adiabaticity criterion for the
interaction of pulses with three-level media has been derived and analyzed in
detail.

</DOC>
<DOC>
<DOCNO> 85546 </DOCNO>
Naked singularities in Tolman-Bondi-de Sitter collapse


  We study the formation of central naked singularities in spherical dust
collapse with a cosmological constant. We find that the central curvature
singularity is locally naked, Tipler strong, and generic, in the sense that it
forms from a non-zero-measure set of regular initial data. We also find that
the Weyl and Ricci curvature scalars diverge at the singularity, with the
former dominating over the latter, thereby signaling the non-local origin of
the singularity.

</DOC>
<DOC>
<DOCNO> 117286 </DOCNO>
Analysis of Density Matrix reconstruction in NMR Quantum Computing


  Reconstruction of density matrices is important in NMR quantum computing. An
analysis is made for a 2-qubit system by using the error matrix method. It is
found that the state tomography method determines well the parameters that are
necessary for reconstructing the density matrix in NMR quantum computations.
Analysis is also made for a simplified state tomography procedure that uses
fewer read-outs. The result of this analysis with the error matrix method
demonstrates that a satisfactory accuracy in density matrix reconstruction can
be achieved even in a measurement with the number of read-outs being largely
reduced.

</DOC>
<DOC>
<DOCNO> 121313 </DOCNO>
A New Quadruple Gravitational Lens System: CLASS B0128+437


  High resolution MERLIN observations of a newly-discovered four-image
gravitational lens system, B0128+437, are presented. The system was found after
a careful re-analysis of the entire CLASS dataset. The MERLIN observations
resolve four components in a characteristic quadruple-image configuration; the
maximum image separation is 542 mas and the total flux density is 48 mJy at 5
GHz. A best-fit lens model with a singular isothermal ellipsoid results in
large errors in the image positions. A significantly improved fit is obtained
after the addition of a shear component, suggesting that the lensing system is
more complex and may consist of multiple deflectors. The integrated radio
spectrum of the background source indicates that it is a GigaHertz-Peaked
Spectrum (GPS) source. It may therefore be possible to resolve structure within
the radio images with deep VLBI observations and thus better constrain the
lensing mass distribution.

</DOC>
<DOC>
<DOCNO> 99848 </DOCNO>
On zeros of solutions of linear differential systems


  An approach is proposed for bounding the number of zeros that solutions of
linear differential systems with polynomial coefficients may have. A bound is
obtained in a special case which improves upon currently existing.

</DOC>
<DOC>
<DOCNO> 118053 </DOCNO>
The stellar content of brightest cluster galaxies


  We present near-infrared K-band spectroscopy of 21 elliptical or cD Brightest
Cluster Galaxies (BCGs), for which we have measured the strength of the 2.293
micron CO stellar absorption feature. We find that the strength of this feature
is remarkably uniform among these galaxies, with a smaller scatter in
equivalent width than for the normal elliptical population in the field or
clusters. The scatter for BCGs is 0.156 nm, compared with 0.240 nm for Coma
cluster ellipticals, 0.337 nm for ellipticals from a variety of other clusters,
and 0.422 nm for field ellipticals. We interpret this homogeneity as being due
to a greater age, or more uniform history, of star formation in BCGs than in
other ellipticals; only a small fraction of the scatter can be due to
metallicity variations, even in the BCGs. Notwithstanding the small scatter,
correlations are found between CO strength and various galaxy properties,
including R-band absolute magnitude, which could improve the precision of these
galaxies as distance indicators in measurements of cosmological parameters and
velocity flows.

</DOC>
<DOC>
<DOCNO> 122663 </DOCNO>
Advection dominated flows around black holes in two dimensions


  We show the results of two-dimensional, azimuthally symmetric simulations of
advection dominated fluid flows around black holes. We use the SPH method, and
the alpha-prescription for the viscosity, including all terms in the stress
tensor. We have performed calculations with 0.001 < alpha < 0.2 and find strong
circulation patterns in the flow, on spatial scales that depend on the
magnitude of the viscosity.

</DOC>
<DOC>
<DOCNO> 123276 </DOCNO>
The Origin of the Magnetic Fields of the Universe: The Plasma


  (abridged) The interpretation of Faraday rotation measure maps of AGNs within
galaxy clusters has revealed regions, $\sim 50-100$ kpc, that are populated
with large, $\sim 30 \mu$ G magnetic fields. The magnetic energy of these
coherent regions is $\sim 10^{59-60}$ ergs, and the total magnetic energy over
the whole cluster ($\sim 1$ Mpc across) is expected to be even larger. A
sequence of physical processes that are responsible for the production,
redistribution and dissipation of these magnetic fields is proposed. These
fields are associated with single AGNs within the cluster and therefore with
all galaxies during their AGN phase, simply because only the central
supermassive black holes ($\sim 10^8 M_{\odot}$) have an accessible energy,
$\sim 10^{61}$ ergs. We propose an $\alpha-\Omega$ dynamo process in an
accretion disk. The disk rotation naturally provides a large winding number,
$\sim 10^{11}$ turns, sufficient to make both large gain and large flux. The
helicity of the dynamo can be generated by the differential plume rotation
derived from star-disk collisions. This helicity generation process has been
demonstrated in the laboratory and the dynamo gain was simulated numerically. A
liquid sodium analog of the dynamo is being built. Speculations are that the
back reaction of the saturated dynamo will lead to the formation of a
force-free magnetic helix, which will carry the energy and flux of the dynamo
away from the accretion disk and redistribute the field within the clusters and
galaxy walls. The magnetic reconnection of a small fraction of this energy
logically is the source of the AGN luminosity, and the remainder of the field
energy should then dominate the free energy of the present-day universe.

</DOC>
<DOC>
<DOCNO> 84989 </DOCNO>
Warm inflation and scalar perturbations of the metric


  A second-order expansion for the quantum fluctuations of the matter field was
considered in the framework of the warm inflation scenario. The friction and
Hubble parameters were expended by means of a semiclassical approach. The
fluctuations of the Hubble parameter generates fluctuations of the metric.
These metric fluctuations produce an effective term of curvature. The power
spectrum for the metric fluctuations can be calculated on the infrared sector.

</DOC>
<DOC>
<DOCNO> 67894 </DOCNO>
Effective Field Theory and $\chi$pt


  A brief introduction to the subject of chiral perturbation theory ($\chi$pt)
is given, including a discussion of effective field theory and application to
the upcoming Bates virtual Compton scattering measurement.

</DOC>
<DOC>
<DOCNO> 174466 </DOCNO>
Multiple Scales in the Fine Structure of the Isoscalar Giant Quadrupole


  The fine structure of the isoscalar giant quadrupole resonance in ^{208}Pb,
observed in high-resolution (p,p') and (e,e') experiments, is studied using the
entropy index method. In a novel way, it enables to determine the number of
scales present in the spectra and their magnitude. We find intermediate scales
of fluctuations around 1.1 MeV, 460 keV and 125 keV for an excitation energy
region 0 - 12 MeV. A comparison with scales extracted from second RPA
calculations, which are in good agreement with experiment, shows that they
arise from the internal mixing of collective motion with two particle-two hole
components of the nuclear wavefunction.

</DOC>
<DOC>
<DOCNO> 121816 </DOCNO>
Interaction rates of dark-matter halos and subhalos


  [Abridged] The interaction rates of dark-matter halos and subhalos, are
computed using high-resolution cosmological N-body simulations of the
Lambda-CDM model. Although the number fraction of subhalos of mass
$>2x10^{11}\hsolmass$ is only ~10%, we find that the interaction rate of such
subhalos is relatively high because they reside in high density environments.
At low redshift, the subhalo collisions dominate the total collision rate, and
even at z=3 they are involved in more than 30% of all collisions. About 40% of
the "major" mergers are between subhalos. Therefore subhalo interactions must
be incorporated in models of structure formation. We find that the collision
rate between halos in physical density units, is $\propto (1+z)^\delta $, with
$\delta = 3-4$, in agreement with earlier simulations and most observational
data. We test previous analytic estimates of the interaction rates of subhalos
based on statistical models, which could be very inaccurate because of the
small number of subhalos and the variation of conditions within small host
halos. We find that, while such statistical estimates may severely overestimate
the rate within hosts $< 10^{13} \hsolmass$, typical of high redshifts, they
are valid for larger hosts regardless of the number of subhalos in them. We
find the Makino & Hut (1997) estimate of the subhalo merger rate to be valid
for hosts $ > 6x10^{11}\hsolmass$ at all redshifts. The collision rate between
subhalos and the central object of their host halo is approximated relatively
well using the timescale for dynamical friction in circular orbits. This
approximation fails in ~40% of the cases, partly because of deviations from the
assumption of circular orbits and partly because of the invalidity of the
assumption that the subhalo mass is negligible.

</DOC>
<DOC>
<DOCNO> 12305 </DOCNO>
Evidence for the singlet-dimer ground state in an S = 1 antiferromag


  Susceptibility, ESR and magnetization measurements have been performed on si
ngle crystals of an S=1 bond alternating chain compound: [Ni(333-tet)(\mu-NO
_2)](ClO_4) (333-tet = N,N'-bis(3-aminopropyl)propane-1,3-diamine) and the c
ompound doped with a small amount of Zn. We observed an anomalous angular de
pendence in the Zn-doped sample. These behaviors are well explained by the m
odel based on the VBS picture for the singlet-dimer phase. The picture impli es
that the free spins of S=1 with a positive single-ion anisotropy are indu ced
at the edges of the chains without forming the singlet-dimer.

</DOC>
<DOC>
<DOCNO> 120271 </DOCNO>
Self-Consistent Response of a Galactic Disk to an Elliptical


  We calculate the self-consistent response of an axisymmetric galactic disk
perturbed by an elliptical halo potential of harmonic number m = 2, and obtain
the net disk ellipticity. Such a potential is commonly expected to arise due to
a galactic tidal encounter and also during the galaxy formation process. The
self-gravitational potential corresponding to the self-consistent,
non-axisymmetric density response of the disk is obtained by inversion of
Poisson equation for a thin disk. This response potential is shown to oppose
the perturbation potential, because physically the disk self-gravity resists
the imposed potential. This results in a reduction in the net ellipticity of
the perturbation halo potential in the disk plane. The reduction factor
denoting this decrease is independent of the strength of the perturbation
potential, and has a typical minimum value of 0.75 - 0.9 for a wide range of
galaxy parameters. The reduction is negligible at all radii for higher
harmonics (m > or = 3) of the halo potential. (abridged).

</DOC>
<DOC>
<DOCNO> 11060 </DOCNO>
Critical dynamics of two-replica cluster algorithms


  The dynamic critical behavior of the two-replica cluster algorithm is
studied. Several versions of the algorithm are applied to the two-dimensional,
square lattice Ising model with a staggered field. The dynamic exponent for the
full algorithm is found to be less than 0.4. It is found that odd translations
of one replica with respect to the other together with global flips are
essential for obtaining a small value of the dynamic exponent.

</DOC>
<DOC>
<DOCNO> 69230 </DOCNO>
Spin structure and longitudinal polarization of hyperon in e+e-


  Longitudinal polarizations of different kinds of hyperons produced in e+e-
annihilation at LEP I and LEP II energies in different event samples are
calculated using two different pictures for the spin structure of hyperon: that
drawn from polarized deep inelastic lepton-nucleon scattering data or that
using SU(6) symmetric wave functions. The result shows that measurements of
such polarizations should provide useful information to the question of which
picture is more suitable in describing the spin effects in the fragmentation
processes.

</DOC>
<DOC>
<DOCNO> 119057 </DOCNO>
Konus catalog of SGR activity to 2000


  Observational data on the bursting activity of all five known Soft Gamma
Repeaters are presented. This information was obtained with Konus gamma-ray
burst experiments on board Venera 11-14, Wind, and Kosmos-2326 spacecraft in
the period from 1978 to 2000. These data on appearance rates, time histories,
and energy spectra of repeated soft bursts obtained with similar instruments
and collected together in a comparable form should be useful for further
studies of SGRs. (available at http://www.ioffe.rssi.ru/LEA/SGR/Catalog/).

</DOC>
<DOC>
<DOCNO> 39654 </DOCNO>
Inclusive Jet Cross Sections in $\bar{p}p$ Collisions at $\sqrt{s}$= 630


  We have made a precise measurement of the inclusive jet cross section at
$\sqrt{s}$=1800 GeV. The result is based on an integrated luminosity of 92
pb^{-1} collected at the Fermilab Tevatron $\bar{p}p$ Collider with the D\O
detector. The measurement is reported as a function of jet transverse energy
(60 GeV <= E_{T} < 550 GeV), and in the pseudorapidity intervals |\eta| <= 0.5
and 0.1 <= |\eta| <= 0.7. A preliminary measurement of the pseudorapidity
dependence of inclusive jet production (|\eta| <= 1.5) is also discussed. The
results are in good agreement with predictions from next-to-leading order (NLO)
quantum chromodynamics (QCD). D\O has also determined the ratio of jet cross
sections at $\sqrt{s}$=630 GeV and $\sqrt{s}$=1800 GeV (|\eta| <= 0.5). This
preliminary measurement differs from NLO QCD predictions.

</DOC>
<DOC>
<DOCNO> 8663 </DOCNO>
Fermi Surface Topology of Bi_{2}Sr_{2}CaCu_{2}O_{8+d} at h\nu=33eV: hole


  We present new results from Angle-Resolved Photoemission experiments (ARPES)
on overdoped Bi_{2}Sr_{2}CaCu_{2}O_{8+d} (BSCCO) crystals. With greatly
improved energy and momentum resolution, we clearly identify the existence of
electron-like portions of the Fermi Surface (FS) near \bar{M} at h\nu=33eV.
This is consistent with previously reported data and is robust against various
FS crossing criteria. It is not due to an artifact induced from
\vec{k}-dependent matrix element effects. We also present evidence for a
breakage in the FS pointing to the possible existence of two types of
electronic components.

</DOC>
<DOC>
<DOCNO> 12040 </DOCNO>
Sympatric speciation: compliance with phenotype diversification from a


  A novel mechanism for sympatric speciation that takes into account complex
bio-processes within each individual organism is proposed. According to
dynamical systems theory, organisms with identical genotypes can possess
differentiated physiological states and may coexist `symbiotically' through
appropriate mutual interaction. With mutations, the phenotypically
differentiated organisms gradually come to possess distinct genotypes, while
maintaining their symbiotic relationship. This symbiotic speciation is robust
against sexual recombination, because offspring of mixed parentage, with
intermediate genotypes, are less fit than their parents. This leads to
sterility of the hybrid. Accordingly, a basis for mating preference also
arises.

</DOC>
<DOC>
<DOCNO> 70044 </DOCNO>
Phenomenology and Cosmology of Supersymmetric Grand Unified Theories


  The cosmological relic density of a Bino-like Lightest Supersymmetric
Particle is calculated in the framework of the Minimal Supersymmetric Standard
Model. We include annihilation and coannihilation effects of the Bino with the
lightest stau and with the other sleptons, which happen to have comparable
masses with it. Coannihilation turns out to be crucial for reducing the Bino
relic density to an acceptable level. Phenomenological constraints, also,
results from the inclusion of the supersymmetric corrections to the CP-even
Higgs boson and b-quark masses and the branching ratio of b -->s gamma. We
impose these constraints on two versions of the Minimal Supersymmetric Standard
Model, employing radiative electroweak breaking with universal boundary
conditions and gauge coupling unification. In the first version of the model we
assume Yukawa coupling unification and boundary conditions from
gravity-mediated supersymmetry breaking. In the second version of the model we
assume boundary conditions from the Horava-Witten theory and we restrict the
parameter space by simultaneously imposing the phenomenological and
cosmological constraints.

</DOC>
<DOC>
<DOCNO> 70000 </DOCNO>
Analysis of the Superkamiokande atmospheric neutrino data in the


  Superkamiokande atmospheric neutrino data for 990 days are analyzed in the
framework of four neutrinos without imposing constraints of Big Bang
Nucleosynthesis. It is shown that the wide range of the oscillation parameters
is allowed at 90% confidence level ($0.1\lsim |U_{s1}|^2+|U_{s2}|^2\le 1$).

</DOC>
<DOC>
<DOCNO> 150521 </DOCNO>
Consistency of Kaluza-Klein Sphere Reductions of Symmetric Potentials


  In a recent paper, the complete (non-linear) Kaluza-Klein Ansatz for the
consistent embedding of certain scalar plus gravity subsectors of gauged
maximal supergravity in D=4, 5 and 7 was presented, in terms of sphere
reductions from D=11 or type IIB supergravity. The scalar fields included in
the truncations were the diagonal fields in the SL(N,R)/SO(N) scalar
submanifolds of the full scalar sectors of the corresponding maximal
supergravities, with N=8, 6 and 5. The embeddings were used for obtaining an
interpretation of extremal D=4, 5 or 7 AdS domain walls in terms of distributed
M-branes or D-branes in the higher dimensions. Although strong supporting
evidence for the correctness of the embedding Ansatze was presented, a full
proof of the consistency was not given. Here, we complete the proof, by showing
explicitly that the full set of higher-dimensional equations of motion are
satisfied if and only if the lower-dimensional fields satisfy the relevant
scalar plus gravity equations.

</DOC>
<DOC>
<DOCNO> 119720 </DOCNO>
Big Bang Leftovers in the Microwave: Cosmology with the Cosmic Microwave


  We combine detections of anisotropy in the Cosmic Microwave Background
radiation with observations of inhomogeneity in the large-scale distribution of
galaxies to test the predictions of models of cosmological structure formation.
This combination probes spatial scales varying by three orders of magnitude,
including a significant region where the two types of data overlap. We examine
Cold Dark Matter models with adiabatic density perturbations, isocurvature
models, and a topological defects model. We set upper limits on the neutrino
mass and find the primordial power spectrum needed to reconcile an apparent
disagreement between structure formation observations and direct observations
of cosmological parameters.
  Present and future observations of Cosmic Microwave Background anisotropy
suffer from foreground contamination. We develop detailed predictions for
microwave emission from radio and infrared-bright galaxies and the
Sunyaev-Zeldovich effect from clusters. We present realistic simulations of the
microwave sky, produced as part of the `WOMBAT Challenge' exercise, and
introduce a pixel-space method for subtracting foreground contamination which
can be tested on these simulations.

</DOC>
<DOC>
<DOCNO> 71348 </DOCNO>
Tagged-photon events in polarized DIS process


  Deep-inelastic events for the scattering of the longitudinally polarized
electron by polarized proton with tagged collinear photon radiated from
initial-state electron are considered. The corresponding cross-section is
derived in the Born approximation. The model-independent radiative corrections
to the Born cross-section are also calculated. Obtained result is applied to
the case of elastic scattering.

</DOC>
<DOC>
<DOCNO> 170623 </DOCNO>
Hiding bits in Bell states


  We present a scheme for hiding bits in Bell states that is secure even when
the sharers Alice and Bob are allowed to carry out local quantum operations and
classical communication. We prove that the information that Alice and Bob can
gain about a hidden bit is exponentially small in $n$, the number of qubits in
each share, and can be made arbitrarily small for hiding multiple bits. We
indicate an alternative efficient low-entanglement method for preparing the
shared quantum states. We discuss how our scheme can be implemented using
present-day quantum optics.

</DOC>
<DOC>
<DOCNO> 80923 </DOCNO>
Discrete Lorentzian Quantum Gravity


  Just as for non-abelian gauge theories at strong coupling, discrete lattice
methods are a natural tool in the study of non-perturbative quantum gravity.
They have to reflect the fact that the geometric degrees of freedom are
dynamical, and that therefore also the lattice theory must be formulated in a
background-independent way. After summarizing the status quo of discrete
covariant lattice models for four-dimensional quantum gravity, I describe a new
class of discrete gravity models whose starting point is a path integral over
Lorentzian (rather than Euclidean) space-time geometries. A number of
interesting and unexpected results that have been obtained for these
dynamically triangulated models in two and three dimensions make discrete
Lorentzian gravity a promising candidate for a non-trivial theory of quantum
gravity.

</DOC>
<DOC>
<DOCNO> 11305 </DOCNO>
Bose-Einstein condensates in standing waves: The cubic nonlinear


  We present a new family of stationary solutions to the cubic nonlinear
Schroedinger equation with a Jacobian elliptic function potential. In the limit
of a sinusoidal potential our solutions model a dilute gas Bose-Einstein
condensate trapped in a standing light wave. Provided the ratio of the height
of the variations of the condensate to its DC offset is small enough, both
trivial phase and nontrivial phase solutions are shown to be stable. Numerical
simulations suggest such stationary states are experimentally observable.

</DOC>
<DOC>
<DOCNO> 120060 </DOCNO>
The Active Nucleus in the Ultraluminous Infrared Galaxy IRAS 08311-2459


  Near-infrared spectroscopy using the new Palomar Integral Field Spectrograph
indicates the presence of an AGN (active galactic nucleus) in the ultraluminous
infrared galaxy IRAS 08311-2459. The high-velocity wings of the Paschen-alpha
hydrogen recombination line are seen to be spatially unresolved, and with no
positional offset between red and blue high velocity emission. The [Si VI]
coronal line, with a 167 eV excitation potential, is also spatially unresolved
with a velocity width comparable to that of the broad component of the Pa-alpha
emission. The low velocity component of the Pa-alpha emission is seen to be
rotating, and is extended over about 2 kpc. Molecular hydrogen is also
extended, and elongated along the maximum velocity gradient, sharing the same
rotation profile as the narrow Pa-alpha emission. The simple picture in
agreement with the observations is that of an AGN surrounded by a rotating disk
of star formation. These observations lend strength to the usage of [Si VI] as
a diagnostic of AGN activity in ultraluminous infrared galaxies, and also
highlight the utility of integral field spectroscopy in elucidating subtle
morphological differences in line emitting regions.

</DOC>
<DOC>
<DOCNO> 83393 </DOCNO>
Parsing with the Shortest Derivation


  Common wisdom has it that the bias of stochastic grammars in favor of shorter
derivations of a sentence is harmful and should be redressed. We show that the
common wisdom is wrong for stochastic grammars that use elementary trees
instead of context-free rules, such as Stochastic Tree-Substitution Grammars
used by Data-Oriented Parsing models. For such grammars a non-probabilistic
metric based on the shortest derivation outperforms a probabilistic metric on
the ATIS and OVIS corpora, while it obtains very competitive results on the
Wall Street Journal corpus. This paper also contains the first published
experiments with DOP on the Wall Street Journal.

</DOC>
<DOC>
<DOCNO> 68960 </DOCNO>
Hybrid Baryon Signatures


  We discuss whether a low-lying hybrid baryon should be defined as a three
quark - gluon bound state or as three quarks moving on an excited adiabatic
potential. We show that the latter definition becomes exact, not only for very
heavy quarks, but also for specific dynamics. We review the literature on the
signatures of hybrid baryons, with specific reference to strong hadronic
decays, electromagnetic couplings, diffractive production and production in psi
decay.

</DOC>
<DOC>
<DOCNO> 119789 </DOCNO>
Implications of the X-Ray Properties of Pulsar Nebulae


  A plausible model for the Crab Nebula is one in which a particle dominated,
highly relativistic wind from the pulsar passes through a shock front in which
the particles attain a power law energy distribution. The electrons and
positrons lose energy radiating synchrotron emission. Here, a one zone version
of the model is developed and applied to observations of X-ray pulsar nebulae.
Efficient conversion of pulsar spin-down power to X-ray luminosity is expected
if the observed electrons are in the synchrotron cooling regime and their
energy spectrum is similar to that in the Crab Nebula. In this case, the
relation between X-ray luminosity and pulsar spin-down power depends only
weakly on the model parameters. The dependence is stronger for a steeper
particle spectrum, as appears to be present in N157B, and the efficiency of
X-ray production can be lower. If the electrons are not in the cooling regime,
the X-ray luminosity can be low, as appears to be the case for the compact
nebula around the Vela pulsar. Slow cooling is likely to be caused by a
sub-equipartition magnetic field in the radiating region. Observations can
place constraints on the uncertain physics of relativistic MHD shocks. The
model is related to those developed for gamma-ray burst afterglows.

</DOC>
<DOC>
<DOCNO> 99365 </DOCNO>
Continuation of Direct Products of Distributions


  If, in some problems, one has to deal with the ``product'' of distributions
$\rm f_i$ (also called generalized functions) $\rm\bar T = \Pi^m_{i=1} f_i$,
this product has a priori no definite meaning as a functional $(\rm \bar T,
\phi) $ for $\rm\phi \in S$. But if $\rm x^{\kappa +1} \Pi^m_{i=1} f_i$ exists,
whatever the associativity is between some powers $\rm r_i$ of $\rm x$ ($\rm
r_i \in \Bbb N, \sum_i r_i\leq \kappa +1, r_i \geq 0$) and the various $\rm
f_i$, then a continuation of the linear functional $\rm \bar T$ from $\rm M$
onto $\rm S^{(N)}$ for some $\rm N$ is shown to exist in such a way that $\rm
x^{\kappa +1} \bar T$ is defined unambiguously, and $\rm (\bar T, \phi), \phi
\in S$, significant, though not unique.

</DOC>
<DOC>
<DOCNO> 9377 </DOCNO>
From GM Law to A Powerful Mean Field Scheme


  A new and powerful mean field scheme is presented. It maps to a
one-dimensional finite closed chain in an external field. The chain size
accounts for lattice topologies. Moreover lattice connectivity is rescaled
according to the GM law recently obtained in percolation theory. The associated
self-consistent mean-field equation of state yields critical temperatures which
are within a few percent of exact estimates. Results are obtained for a large
variety of lattices and dimensions. The Ising lower critical dimension for the
onset of phase transitions is $d_l=1+\frac{2}{q}$. For the Ising hypercube it
becomes the Golden number $d_l=\frac{1+\sqrt 5}{2}$. The scheme recovers the
exact result of no long range order for non-zero temperature Ising triangular
antiferromagnets.

</DOC>
<DOC>
<DOCNO> 117248 </DOCNO>
Contribution of the screened self-energy to the Lamb shift of


  Expressions for the effective Quantum Electrodynamics (QED) Hamiltonian due
to self-energy screening (self-energy correction to the electron-electron
interaction) are presented. We use the method of the two-time Green's function,
which handles quasidegenerate atomic states. From these expression one can
evaluate energy corrections to, e.g., 1s2p 3P1 and 1s2p 1P1 levels in helium
and two-electron ions, to all orders in Z\alpha

</DOC>
<DOC>
<DOCNO> 102816 </DOCNO>
Stability of travelling-wave solutions for reaction-diffusion-convection


  We are concerned with the asymptotic behaviour of classical solutions of
systems of the form u_t = Au_xx + f(u, u_x), x in R, t>0, u(x,t) a vector in
RN, with u(x,0)= U(x), where A is a positive-definite diagonal matrix and f is
a 'bistable' nonlinearity satisfying conditions which guarantee the existence
of a comparison principle. Suppose that there is a travelling-front solution w
with velocity c, that connects two stable equilibria of f. We show that if U is
bounded, uniformly continuously differentiable and such that w(x) - U(x) is
small when the modulus of x is large, then there exists y in R such that u(.,
t) converges to w(.+y-ct) in the C1 norm at an exponential rate as t tends to
infinity. Our approach extends an idea developed by Roquejoffre, Terman and
Volpert in the convectionless case, where f is independent of u_x.

</DOC>
<DOC>
<DOCNO> 118829 </DOCNO>
Evolutionary Timescale of the DAV G117-B15A: The Most Stable Optical


  We observe G117-B15A, the most precise optical clock known, to measure the
rate of change of the main pulsation period of this blue-edge DAV white dwarf.
Even though the obtained value is only within 1 sigma, Pdot = (2.3 +/- 1.4) x
10^{-15} s/s, it is already constraining the evolutionary timescale of this
cooling white dwarf star.

</DOC>
<DOC>
<DOCNO> 8185 </DOCNO>
Three-body recombination in Bose gases with large scattering length


  An effective field theory for the three-body system with large scattering
length is applied to three-body recombination to a weakly-bound s-wave state in
a Bose gas. Our model independent analysis demonstrates that the three-body
recombination constant alpha is not universal, but can take any value between
zero and 67.9 \hbar a^4/m, where a is the scattering length. Other low-energy
three-body observables can be predicted in terms of a and alpha. Near a
Feshbach resonance, alpha should oscillate between those limits as the magnetic
field B approaches the point where a -> infinity. In any interval of B over
which a increases by a factor of 22.7, alpha should have a zero.

</DOC>
<DOC>
<DOCNO> 9383 </DOCNO>
Hall state quantization in a rotating frame


  We derive electromagnetomotive force fields for charged particles moving in a
rotating Hall sample, satisfying a twofold U(1) gauge invariance principle. It
is then argued that the phase coherence property of quantization of the line
integral of total collective particle momentum into multiples of Planck's
quantum of action is solely responsible for quantization in the Hall state. As
a consequence, the height of the Hall quantization steps should remain
invariant in a rapidly rotating Hall probe. Quantum Hall particle
conductivities do not depend on charge and mass of the electron, and are
quantized in units of the inverse of Planck's action quantum.

</DOC>
<DOC>
<DOCNO> 102471 </DOCNO>
Geometry of the trilogarithm and the motivic Lie algebra of a field


  We express the Aomoto trilogarithm explicitely via classical trilogarithm and
investigate the algebraic-geometric structures behind this: different
realuzations of the weight three motivic complexes.
  Using this results we give an explicit motivic construction of the
Grassmannian 4-logarithm and Borel regulator map for K_7(C).

</DOC>
<DOC>
<DOCNO> 122927 </DOCNO>
A Search for CO in the Local Group Dwarf Irregular Galaxy WLM


  We present 12CO J = 1-0 and J = 2-1 observations of the low metallicity (12 +
log(O/H) = 7.74) Local Group dwarf irregular galaxy WLM made with the 15 m SEST
and 14 m FCRAO telescopes. Despite the presence a number of HII regions, we
find no CO emission. We obtain low upper limits on the integrated intensity
(I(CO) >= 0.18 K km/s for CO (1-0)). The non-detection is consistent with the
result of Taylor, Kobulnicky and Skillman (1998), that dwarf galaxies below a
metallicity of ~ 7.9 are not detected in CO emission. WLM shows that this trend
continues for low metallicity galaxies even as their metallicities approach
7.9. These results are consistent with the models of the metal poor ISM by
Norman and Spaans (1997). By comparing our CO data with observations of star
formation in WLM, we find evidence for a high CO to H$_2$ conversion factor.

</DOC>
<DOC>
<DOCNO> 178502 </DOCNO>
Statistical analysis of light fragment production from medium energy


  The light fragment production reactions for 10 MeV to 3 GeV protons incident
on O-16, Al-27, Fe, Nb-93, and Ag are analyzed by a combination of an
intranuclear cascade model and a generalized evaporation model which includes
light nuclei up to Mg as ejectiles. It is concluded that evaporation is the
dominant process by which particles lighter than or equal to Be are produced
from targets heavier than O.

</DOC>
<DOC>
<DOCNO> 150668 </DOCNO>
Conformal nature of the Hawking radiation


  String theory usually represents quantum black holes as systems whose
statistical mechanics reproduces Hawking's thermodynamics in a very
satisfactory way. Complicated brane theoretical models are worked out, as
quantum versions of Supergravity solutions. These models are then assumed to be
in thermal equilibrium: this is a little cheating, because one is looking for
an explanation of the seeming thermodynamical nature of black holes, so they
cannot be {\it assumed} to be finite temperature systems! In the model
presented here, the black body spectrum arises with no statistical hypothesis
as an approximation of the unitary evolution of microscopic black holes, which
are always described by a 1+1 conformal field theory, characterized by some
Virasoro algebra. At the end, one can state that {\it the
Hawking-thermodynamics of the system is a by-product of the algebraic
Virasoro-symmetric nature of the event horizon}. This is {\it the central
result} of the present work.

</DOC>
<DOC>
<DOCNO> 70707 </DOCNO>
The gamma -> 3 pi form factor as a constraint on Schwinger-Dyson


  The form factor for gamma pi^+ -> pi^+ pi^0 was calculated in a simple-minded
constituent model with a constant quark mass parameter, as well as in the
Schwinger-Dyson approach. The comparative discussion of these and various other
theoretical results on this anomalous process, as well as the scarce already
available data (hopefully to be supplemented by more accurate CEBAF data soon),
seem to favor Schwinger-Dyson modeling which would yield relatively small
low-momentum values of the constituent (dynamically dressed) quark mass
function.

</DOC>
<DOC>
<DOCNO> 121865 </DOCNO>
Rotation and lithium in single giant stars


  In the present work, we study the link between rotation and lithium abundance
in giant stars of luminosity class III, on the basis of a large sample of
single stars of spectral type F, G and K. We shows that giant stars presenting
the highest lithium contents, typically stars earlier than G0III, are those
with the highest rotation rates, pointing for a dependence of lithium content
on rotation, as observed for other luminosity classes. Giant stars later than
G0III present, as a rule, the lowest rotation rates and lithium contents. A
large spread of about five magnitudes in lithium abundance is observed for the
slow rotators. Finally, single giant stars with masses 1.5 < M/Msun <= 2.5 show
a clearest trend for a correlation between rotational velocity and lithium
abundance.

</DOC>
<DOC>
<DOCNO> 116502 </DOCNO>
Interstellar Hydrogen and Cosmic Background Radiation


  It is shown that a collection of photons with nearly the same frequency
exhibits a "condensation" type of phenomenon corresponding to a peak intensity.
The observed cosmic background radiation can be explained from this standpoint
in terms of the radiation due to fluctuations in interstellar Hydrogen.

</DOC>
<DOC>
<DOCNO> 101905 </DOCNO>
Amoebas of maximal area


  To any algebraic curve A in a complex 2-torus $(\C^*)^2$ one may associate a
closed infinite region in a real plane called the amoeba of A. The amoebas of
different curves of the same degree come in different shapes and sizes. All
amoebas in have finite area and, furthermore, there is an upper bound on the
area in terms of the degree of the curve.
  The subject of this paper is the curves in a complex 2-torus whose amoebas
are of the maximal area. We show that up to multiplication by a constant such
curves are defined over real numbers and, furthermore, that their real loci are
isotopic to so-called Harnack curves.

</DOC>
<DOC>
<DOCNO> 152132 </DOCNO>
The periodic and open Toda lattice


  We develop algebro-geometrical approach for the open Toda lattice. For a
finite Jacobi matrix we introduce a singular reducible Riemann surface and
associated Baker-Akhiezer functions. We provide new explicit solution of
inverse spectral problem for a finite Jacoby matrix. For the Toda lattice
equations we obtain the explicit form of the equations of motion, the
symplectic structure and Darboux coordinates. We develop similar approach for
2D open Toda. Explaining some the machinery we also make contact with the
periodic case.

</DOC>
<DOC>
<DOCNO> 118264 </DOCNO>
Spatially-resolved spectra of the accretion disc of the novalike UU


  Time-resolved spectroscopy of the novalike variable UU Aquarii is analyzed
with eclipse mapping techniques to produce spatially resolved spectra of its
accretion disc and gas stream as a function of distance from disc centre in the
range 3600-6900 \AA. The spatially-resolved spectra show that the continuum
emission becomes progressively fainter and redder for increasing disc radius --
reflecting the radial temperature gradient -- and reveal that the HI and HeI
lines appear as deep, narrow absorption features in the inner disc regions
transitioning to emission with P Cygni profiles for intermediate and large disc
radii. The spectrum of the uneclipsed component has strong HI and HeI emission
lines plus a Balmer jump in emission and is explained as optically thin
emission from a vertically extended disc chromosphere + wind. Most of the line
emission probably arises from the wind. The spatially-resolved spectra also
suggest the existence of gas stream ``disk-skimming'' overflow in UU Aqr, which
can be seen down to R \simeq 0.2 R_{L1}. The comparison of our eclipse maps
with those of Baptista, Steiner & Horne (1996) suggests that the asymmetric
structure in the outer disc previously identified as the bright spot may be the
signature of an elliptical disc similar to those possibly present in SU UMa
stars during superoutbursts.

</DOC>
<DOC>
<DOCNO> 83215 </DOCNO>
Noun Phrase Recognition by System Combination


  The performance of machine learning algorithms can be improved by combining
the output of different systems. In this paper we apply this idea to the
recognition of noun phrases.We generate different classifiers by using
different representations of the data. By combining the results with voting
techniques described in (Van Halteren et.al. 1998) we manage to improve the
best reported performances on standard data sets for base noun phrases and
arbitrary noun phrases.

</DOC>
<DOC>
<DOCNO> 39929 </DOCNO>
Mighty MURINEs: Neutrino Physics at Very High Energy Muon Colliders


  An overview is given of the potential for neutrino physics studies through
parasitic use of the intense high energy neutrino beams that would be produced
at future many-TeV muon colliders. Neutrino experiments clearly cannot compete
with the collider physics. Except at the very highest energy muon colliders,
the main thrust of the neutrino physics program would be to improve on the
measurements from preceding neutrino experiments at lower energy muon
colliders, particularly in the fields of B physics, quark mixing and CP
violation. Muon colliders at the 10 TeV energy scale might already produce of
order 10^8 B hadrons per year in a favorable and unique enough experimental
environment to have some analytical capabilities beyond any of the currently
operating or proposed B factories. The most important of the quark mixing
measurements at these energies might well be the improved measurements of the
important CKM matrix elements |V_ub| and |V_cb| and, possibly, the first
measurements of |V_td| in the process of flavor changing neutral current
interactions involving a top quark loop. Muon colliders at the highest
center-of-mass energies that have been conjectured, 100--1000 TeV, would
produce neutrino beams for neutrino-nucleon interaction experiments with
maximum center-of-mass energies from 300--1000 GeV. Such energies are
comparable to the 314 GeV center-of-mass energy for electron-proton scattering
at the HERA collider, but the luminosity would would be several orders of
magnitude larger. This would potentially open up the possibility for high
statistics studies of any exotic particles, such as leptoquarks, that might
have been previously discovered at these energy scales.

</DOC>
<DOC>
<DOCNO> 119741 </DOCNO>
X-ray Line Diagnostics of Hot Accretion Flows around Black Holes


  We compute X-ray emission lines from thermal plasma in hot accretion flows.
We show that line profiles are strong probes of the gas dynamics, and we
present line-ratio diagnostics which are sensitive to the distribution of mass
with temperature in the flow. We show how these can be used to constrain the
run of density with radius, and the size of the hot region. We also present
diagnostics which are primarily sensitive to the importance of recombination
versus collisional ionization, and which could help discriminate ADAFs from
photoionization-dominated accretion disk coronae. We apply our results to the
Galactic center source Sagittarius A* and to the nucleus of M87. We find that
the brightest predicted lines are within the detection capability of current
$X$-ray instruments.

</DOC>
<DOC>
<DOCNO> 101466 </DOCNO>
Action of the mapping class group on a complex of curves and a


  S. Gervais gave a finite presentation for the mapping class group of a
surface (math.GT/9811162). We show this presentation without using Wajnryb's
simple presentation. We use a complex of curves defined by Harvey, in place of
Hatcher and Thurston's complex.

</DOC>
<DOC>
<DOCNO> 39771 </DOCNO>
New constraints on WIMPs from the Canfranc IGEX dark matter search


  The IGEX Collaboration enriched 76Ge double-beta decay detectors are
currently operating in the Canfranc Underground Laboratory with an overburden
of 2450 m.w.e. A recent upgrade has made it possible to use them in a search
for WIMPs. A new exclusion plot has been derived for WIMP-nucleon
spin-independent interaction. To obtain this result, 30 days of data from one
IGEX detector, which has an energy threshold of ~4 keV, have been considered.
These data improve the exclusion limits derived from other germanium diode
experiments in the ~50 GeV DAMA region, and show that with a moderate
improvement of the background below 10 keV, the DAMA region may be tested with
an additional 1 kg-year of exposure.

</DOC>
<DOC>
<DOCNO> 80898 </DOCNO>
Flavour singlet pseudoscalar masses in N_f = 2 QCD


  We perform a lattice mass analysis in the flavour singlet pseudoscalar
channel on the SESAM and TXL full QCD vacuum configurations, with 2 active
flavours of dynamical Wilson fermions at beta = 5.6. At our inverse lattice
spacing, a^-1 = 2.3 GeV, we retrieve by a chiral extrapolation to the physical
light quark masses the value m_eta' = 3.7(+8)(-4) m_pi. A crude extrapolation
from (N_f = 3) phenomenology would suggest m_eta' \approx 5.1 m_pi for N_f = 2
QCD. we verify that the mass gap between the singlet state eta' and the pi
flavour triplt state is due to gauge configurations with non-trivial topology.

</DOC>
<DOC>
<DOCNO> 99735 </DOCNO>
The structure of smooth algebras in Kapranov's framework for


  In Kapranov, M. {\it Noncommutative geometry based on commutator expansions,}
J. reine angew. Math {\bf 505} (1998) 73-118, a theory of noncommutative
algebraic varieties was proposed. Here we prove a structure theorem for the
noncommutative coordinate rings of affine open subsets of such of those
varieties which are smooth (Theorem 3.4). The theorem describes the local ring
of a point as a truncation of a quantization of the enveloping Poisson algebra
of a smooth commutative local algebra. An explicit descripition of this
quantization is given in Theorem 2.5. A description of the $A$- module
structure of the Poisson envelope of a smooth commutative algebra $A$ was given
in loc. cit., Theorem 4.1.3. However the proof given in loc. cit. has a gap. We
fix this gap for $A$ local (Theorem 1.4) and prove a weaker global result
(Theorem 1.6).

</DOC>
<DOC>
<DOCNO> 69835 </DOCNO>
Elastic neutrino - electron scattering and potential effects of magnetic


  We consider elastic neutrino - electron scattering of solar neutrinos with
magnetic moments and electric dipole moments, where the solar neutrino state at
the scattering site is determined by the evolution in matter and solar magnetic
fields of the initial electron neutrino state. We present the general cross
section for an arbitrary superposition of active and sterile neutrino types
with positive and negative helicities, with particular emphasis on the effect
of transverse polarization, which gives rise to an azimuthal asymmetry as a
function of the recoil electron momentum. Within our physically motivated
approximation, we perform a general CP analysis and show that in the 1-Dirac
and 2-Majorana neutrino cases no CP-violating effects are present, which means
that it is not possible to distinguish between magnetic and electric dipole
moments in these cases. We also study the consequences of neutrino energy
averaging on the cross section and stress that in the 2-Majorana neutrino case
this averaging leads to a suppression of the transverse neutrino polarization
effects.

</DOC>
<DOC>
<DOCNO> 117263 </DOCNO>
Proposal for an Experimental Test of the Role of Confining Potentials in


  We propose an experiment using a three-gate quantum Hall device to probe the
dependence of the integral quantum Hall effect (IQHE) on the shape of the
lateral confining potential in edge regions. This shape can, in a certain
configuration determine whether or not the IQHE occurs.

</DOC>
<DOC>
<DOCNO> 40644 </DOCNO>
ElectroOptical measurements of ultrashort 45 MeV electron beam bunch


  We have made an observation of 45 MeV electron beam bunches using the
nondestructive electro-optical (EO) technique. The amplitude of the EO
modulation was found to increase linearly with electron beam charge and
decrease inversely with the optical beam path distance from the electron beam.
The risetime of the signal was bandwidth limited by our detection system to
\~70ps. An EO signal due to ionization caused by the electrons traversing the
EO crystal was also observed. The EO technique may be ideal for the measurement
of bunch structure with femtosecond resolution of relativistic charged particle
beam bunches.

</DOC>
<DOC>
<DOCNO> 71250 </DOCNO>
Preheating and phase transitions in gauge theories


  It has recently been suggested that the baryon washout problem of the
standard electroweak baryogenesis scenario could be avoided if inflation ends
with a period of parametric resonance at a low enough energy density. I present
results of numerical simulations in which this process was studied in the
Abelian Higgs model. Our results show that because of the masslessness of the
gauge field, the parametric resonance takes place naturally, and that the
system reaches a quasi-equilibrium state in which the long-wavelength part of
the spectrum has a high effective temperature. This enhances baryon number
violation and makes baryogenesis more efficient.

</DOC>
<DOC>
<DOCNO> 174517 </DOCNO>
Multifragmentation of a very heavy nuclear system (I): Selection of


  A sample of `single-source' events, compatible with the multifragmentation of
very heavy fused systems, are isolated among well-measured 155Gd+natU 36AMeV
reactions by examining the evolution of the kinematics of fragments with Z>=5
as a function of the dissipated energy and loss of memory of the entrance
channel. Single-source events are found to be the result of very central
collisions. Such central collisions may also lead to multiple fragment emission
due to the decay of excited projectile- and target-like nuclei and so-called
`neck' emission, and for this reason the isolation of single-source events is
very difficult. Event-selection criteria based on centrality of collisions, or
on the isotropy of the emitted fragments in each event, are found to be
inefficient to separate the two mechanisms, unless they take into account the
redistribution of fragments' kinetic energies into directions perpendicular to
the beam axis. The selected events are good candidates to look for bulk effects
in the multifragmentation process.

</DOC>
<DOC>
<DOCNO> 99462 </DOCNO>
A Simple Topological Characterization of Regions of Bounded Type


  We prove that there is a one-to-one, bounded, holomorphic function on a
region $\Omega$ iff $S^{2} - \Omega$ is not totally disconnected.
  This paper has been withdrawn by the author since Theorem 3 is incorrect.

</DOC>
<DOC>
<DOCNO> 70178 </DOCNO>
Simple predictions from ALCOR_c for rehadronisation of charmed quark


  We study the production of charmed hadrons with the help of ALCOR_c, the
algebraic coalescence model for rehadronisation of charmed quark matter.
Mesonic ratios are introduced as factors connecting various antibaryon to
baryon ratios. The resulting simple relations could serve as tests of quark
matter formation and coalescence type rehadronization in heavy ion collisions.

</DOC>
<DOC>
<DOCNO> 102022 </DOCNO>
q-Bessel-Macdonald functions


  The modified q-Bessel functions and the q-Bessel-Macdonald functions of the
first and second kind are introduced. Their definition is based on
representations as power series. Recurrence relations, the q-Wronskians,
asymptotic decompositions and q-integral representations are received. In
addition, the q-Bessel-Macdonald function of kind 3 is determined by its
q-integral representation.

</DOC>
<DOC>
<DOCNO> 174479 </DOCNO>
Tables of internal conversion coefficients for superheavy elements


  The internal conversion coefficients for the elements 104 <= Z <= 126 are
presented.

</DOC>
<DOC>
<DOCNO> 7922 </DOCNO>
Spectra of massive and massless QCD Dirac operators: A novel link


  We show that integrable structure of chiral random matrix models
incorporating global symmetries of QCD Dirac operators (labeled by the Dyson
index beta=1,2, and 4) leads to emergence of a connection relation between the
spectral statistics of massive and massless Dirac operators. This novel link
established for beta-fold degenerate massive fermions is used to explicitly
derive (and prove the random matrix universality of) statistics of low--lying
eigenvalues of QCD Dirac operators in the presence of SU(2) massive fermions in
the fundamental representation (beta=1) and SU(N_c >= 2) massive adjoint
fermions (beta=4). Comparison with available lattice data for SU(2) dynamical
staggered fermions reveals a good agreement.

</DOC>
<DOC>
<DOCNO> 152344 </DOCNO>
*-Trek II: *_n Operations, Open Wilson Lines and the Seiberg-Witten Map


  Generalizations of the *-product (e.g. n-ary *_n operations) appear in
various places in the discussion of noncommutative gauge theories. These
include the one-loop effective action of noncommutative gauge theories, the
couplings between massless closed and open string modes, and the Seiberg-Witten
map between the ordinary and noncommutative Yang-Mills fields. We propose that
the natural way to understand the *_n operations is through the expansion of an
open Wilson line. We establish the connection between an open Wilson line and
the *_n operations and use it to: (I) write down a gauge invariant effective
action for the one-loop F^4 terms in the noncommutative N=4 SYM theory; (II)
find the gauge invariant couplings between the noncommutative SYM modes and the
massless closed string modes in flat space; (III) propose a closed form for the
Seiberg-Witten map in the U(1) case.

</DOC>
<DOC>
<DOCNO> 116289 </DOCNO>
From quantum motion to classical motion - seeking the lost reality


  We show that the natural motion of particles in continuous space-time (CSTM)
is not classical continuous motion (CCM), but one kind of essentially
discontinuous motion, the wave function in quantum mechanics is the very
mathematical complex describing this kind of motion, and Schrodinger equation
is just its simplest nonrelativistic motion equation, we call such motion
quantum discontinuous motion or quantum motion; furthermore, we show that, when
considering gravity the space-time will be essentially discrete, and the motion
in discrete space-time (DSTM) will naturally result in the collapse process of
the wave function, this finally brings about the appearance of classical
continuous motion (CCM) in macroscopic world.

</DOC>
<DOC>
<DOCNO> 152185 </DOCNO>
A Field-Theoretic Approach to Connes' Gauge Theory on $M_4\times Z_2$


  Connes' gauge theory on $M_4\times Z_2$ is reformulated in the Lagrangian
level. It is pointed out that the field strength in Connes' gauge theory is not
unique. We explicitly construct a field strength different from Connes' one and
prove that our definition leads to the generation-number independent Higgs
potential. It is also shown that the nonuniqueness is related to the assumption
that two different extensions of the differential geometry are possible when
the extra one-form basis $\chi$ is introduced to define the differential
geometry on $M_4\times Z_2$. Our reformulation is applied to the standard model
based on Connes' color-flavor algebra. A connection between the unimodularity
condition and the electric charge quantization is then discussed in the
presence or absence of $\nu_R$.

</DOC>
<DOC>
<DOCNO> 8951 </DOCNO>
Absorbing-state phase transitions in fixed-energy sandpiles


  We study sandpile models as closed systems, with conserved energy density
$\zeta$ playing the role of an external parameter. The critical energy density,
$\zeta_c$, marks a nonequilibrium phase transition between active and absorbing
states. Several fixed-energy sandpiles are studied in extensive simulations of
stationary and transient properties, as well as the dynamics of roughening in
an interface-height representation. Our primary goal is to identify the
universality classes of such models, in hopes of assessing the validity of two
recently proposed approaches to sandpiles: a phenomenological continuum
Langevin description with absorbing states, and a mapping to driven interface
dynamics in random media. Our results strongly suggest that there are at least
three distinct universality classes for sandpiles.

</DOC>
<DOC>
<DOCNO> 169941 </DOCNO>
Effects of Local Fields on Spontaneous Emission in Dielectric Media


  The local-field renormalization of the spontaneous emission rate in a
dielectric is explicitly obtained from a fully microscopic
quantum-electrodynamical, many-body derivation of Langevin-Bloch operator
equations for two-level atoms embedded in an absorptive and dispersive, linear
dielectric host. We find that the dielectric local-field enhancement of the
spontaneous emission rate is smaller than indicated by previous studies.

</DOC>
<DOC>
<DOCNO> 178963 </DOCNO>
Dibaryons as canonically quantized biskyrmions


  The characteristic feature of the ground state configuration of the Skyrme
model description of nuclei is the absence of recognizable individual nucleons.
The ground state of the skyrmion with baryon number 2 is axially symmetric, and
is well approximated by a simple rational map, which represents a direct
generalization of Skyrme's hedgehog ansatz for the nucleon. If the Lagrangian
density is canonically quantized this configuration may support excitations
that lie close and possible below the threshold for pion decay, and therefore
describe dibaryons. The quantum corrections stabilize these solutions, the mass
density of which have the correct exponential fall off at large distances.

</DOC>
<DOC>
<DOCNO> 152430 </DOCNO>
(NS5,Dp) and (NS5,D(p+2),Dp) bound states of type IIB and type IIA


  Starting from the (q,p) 5-brane solution of type IIB string theory, we here
construct the low energy configuration corresponding to (NS5,Dp)-brane bound
states (for $0\leq p\leq 4$) using the T-duality map between type IIB and type
IIA string theories. We use the SL(2,Z) symmetry on the type IIB bound state
(NS5,D3) to construct (NS5,D5,D3) bound state. We then apply T-duality
transformation again on this state to construct the bound states of the form
(NS5,D(p+2),Dp) (for $0\leq p\leq 2$) of both type IIB and type IIA string
theories. We give the tension formula for these states and show that they form
non-threshold bound states. All these states preserve half of the space-time
supersymmetries of string theories. We also briefly discuss the ODp-limits
corresponding to (NS5,Dp) bound state solutions.

</DOC>
<DOC>
<DOCNO> 8689 </DOCNO>
Ordered phase in the two-dimensional randomly coupled ferromagnet


  True ground states are evaluated for a 2d Ising model with random near
neighbor interactions and ferromagnetic second neighbor interactions (the
Randomly Coupled Ferromagnet). The spin glass stiffness exponent is positive
when the absolute value of the random interaction is weaker than the
ferromagnetic interaction. This result demonstrates that in this parameter
domain the spin glass like ordering temperature is non-zero for these systems,
in strong contrast to the 2d Edwards-Anderson spin glass.

</DOC>
<DOC>
<DOCNO> 121641 </DOCNO>
Analysis of isoplanatic high resolution stellar fields by Starfinder


  We describe a new code for the deep analysis of stellar fields, designed for
Adaptive Optics Nyquist-sampled images with high and low Strehl ratio. The
Point Spread Function is extracted directly from the image frame, to take into
account the actual structure of the instrumental response and the atmospheric
effects. The code is written in IDL language and organized in the form of a
self-contained widget-based application, provided with a series of tools for
data visualization and analysis. A description of the method and some
applications to AO data are presented.

</DOC>
<DOC>
<DOCNO> 170489 </DOCNO>
Quantum Dynamics of Three Coupled Atomic Bose-Einstein Condensates


  The simplest model of three coupled Bose-Einstein Condensates (BEC) is
investigated using a group theoretical method. The stationary solutions are
determined using the SU(3) group under the mean field approximation. This
semiclassical analysis using the system symmetries shows a transition in the
dynamics of the system from self trapping to delocalization at a critical value
for the coupling between the condensates. The global dynamics are investigated
by examination of the stable points and our analysis shows the structure of the
stable points depends on the ratio of the condensate coupling to the
particle-particle interaction, undergoes bifurcations as this ratio is varied.
This semiclassical model is compared to a full quantum treatment, which also
displays the dynamical transition. The quantum case has collapse and revival
sequences superposed on the semiclassical dynamics reflecting the underlying
discreteness of the spectrum. Non-zero circular current states are also
demonstrated as one of the higher dimensional effects displayed in this system.

</DOC>
<DOC>
<DOCNO> 101490 </DOCNO>
Enumeration of chord diagrams


  We determine the number of nonequivalent chord diagrams of order $n$ under
the action of two groups, $C_{2n}$, a cyclic group of order $2n$, and $D_{2n}$,
a dihedral group of order $4n$. Asymptotic formulas are also established.

</DOC>
<DOC>
<DOCNO> 70077 </DOCNO>
Flow equations in the light-front QCD


  Flow equations method of continuous unitary transformations is used to
eliminate the minimal quark-gluon interaction in the light-front quantized QCD
Hamiltonian. The coupled differential equations in the two lowest Fock sectors
correspond to the renormalization of the light-front gluon mass and the
generation of effective quark-antiquark interaction. The influence of the
renormalization of the gluon effective mass on the elimination of the
quark-gluon coupling and the induced quark-antiquark interaction is taken into
account. Namely, the original gauge field coupling can be completely
eliminated, even when the states connected by this interaction are degenerate.
Furthermore, even in the case where effective interaction, obtained within
perturbative schemes (bound state perturbation theory or perturbative
similarity approach), is not defined, we obtain more singular behavior $1/q^4$
at small gluon momenta. This is due to asymptotic behavior of the effective
gluon mass at small cutoffs. By discussing the consequences of this asymptotic
behavior, it seems that our approach is superior to perturbation theory and to
perturbative similarity approach.

</DOC>
<DOC>
<DOCNO> 117899 </DOCNO>
Probing black hole X-ray binaries with the Keck telescopes


  The advent of the large effective apertures of the Keck telescopes has
resulted in the determination with unprecedented accuracy of the mass functions
and mass ratios of faint (R ~ 21 mag) X-ray transients (GS 2000+25, GRO
J0422+32, Nova Oph 1977, Nova Vel 1993), as well as constraining the
main-sequence companion star parameters and producing images of the accretion
disks around the black holes.

</DOC>
<DOC>
<DOCNO> 102583 </DOCNO>
General Forms of a N-fold Supersymmetric Family


  We report general forms of one family of the N-fold supersymmetry in
one-dimensional quantum mechanics. The N-fold supersymmetry is characterized by
the supercharges which are N-th order in differential operators. The family
reported here is defined as a particular form of the supercharges and is
referred to as ``type A''. We show that a quartic and a periodic potentials,
which were previously found to be N-fold supersymmetric by the authors, are
realized as special cases of this type A family.

</DOC>
<DOC>
<DOCNO> 117494 </DOCNO>
Large-scale shocks in the starburst galaxy NGC253. Interferometer


  This paper presents the first high-resolution SiO map made in an external
galaxy. The nucleus of the nearby barred spiral NGC253 has been observed
simultaneously in the v=0, J=2-1 line of SiO and in the J=1-0 line of H13CO+
with the IRAM interferometer, with a resolution of 7.5"x2.6". Emission from SiO
and H13CO+ is extended in the nucleus of NGC253. The bulk of the SiO/H13CO+
emission arises from a 600pcx250pc circumnuclear disk (CND) with a double
ringed structure. The inner ring, of radius r=60pc, viewed edge-on along
PA=51deg, hosts the nuclear starburst; the outer pseudo-ring opens out as a
spiral-like arc up to r=300pc. The kinematics of the gaseous disk,
characterized by strong non-circular motions, is interpreted in terms of the
resonant response of the gas to the barred potential. The inner ring would
correspond to the inner Inner Lindblad Resonance(iILR), whereas the outer
region is linked to the onset of a trailing spiral wave across the outer ILR
(oILR). Most notably, we report the detection of a molecular gas counterpart of
the giant outflow of hot gas, previously seen in X-ray and optical lines, and
tentatively identified as a dust chimney in the the 450mu continuum band.The
SiO shows a high average fractional abundance in the CND of X(SiO)=1.5x10E-10.
This is more than an order of magnitude above the predicted value of a PDR.
Moreover, X(SiO) varies at least by an order of magnitude between the inner
starburst region, which dominates the global emission, where we derive
X(SiO)=1--2x10E-10, and the outer region, where X(SiO) reaches a few 10E-9. SiO
abundance is also significantly enhanced in the outflow (X(SiO)=3--5x10E-10).
Different mechanisms are explored to explain the unlike chemical processing of
molecular gas within the nucleus.

</DOC>
<DOC>
<DOCNO> 102014 </DOCNO>
Surfaces with triple points


  In this paper we compute upper bounds for the number of ordinary triple
points on a hypersurface in $P^3$ and give a complete classification for degree
six (degree four or less is trivial, and five is elementary). But the real
purpose is to point out the intricate geometry of examples with many triple
points, and how it fits with the general classification of surfaces.

</DOC>
<DOC>
<DOCNO> 12800 </DOCNO>
Self-consistent approach for thermodynamics of a simplified


  We present the method of the self-consistent calculation of thermodynamical
and correlation functions. This approach is based on the GRPA (generalized
random phase approximation) scheme with the inclusion of the mean field
corrections.
 Investigation of a pseudospin-electron model (PEM) within the framework of the
presented method shows that interaction between the electron and pseudospin
subsystems leads to the possibility of either first or second order phase
transitions between different uniform phases (bistability) as well as between
the uniform and the chess-board ones.
 In the regime n=const, an instability with respect to phase separation in the
electron and pseudospin subsystems can take place.

</DOC>
<DOC>
<DOCNO> 10240 </DOCNO>
Real-time nonequilibrium dynamics in hot QED plasmas: dynamical


  We study the real-time nonequilibrium dynamics in hot QED plasmas
implementing a dynamical renormalization group and using the hard thermal loop
(HTL) approximation. The focus is on the study of the relaxation of gauge and
fermionic mean fields and on the quantum kinetics of the photon and fermion
distribution functions. For semihard photons of momentum eT << k << T we find
to leading order in the HTL that the gauge mean field relaxes in time with a
power law as a result of infrared enhancement of the spectral density near the
Landau damping threshold. The dynamical renormalization group reveals the
emergence of detailed balance for microscopic time scales larger than 1/k while
the rates are still varying with time. The quantum kinetic equation for the
photon distribution function allows us to study photon production from a
thermalized quark-gluon plasma (QGP) by off-shell effects. We find that for a
QGP at temperature T ~ 200 MeV and of lifetime 10 < t < 50 fm/c the hard (k ~
T) photon production from off-shell bremsstrahlung (q -> q \gamma and \bar{q}
-> \bar{q}\gamma) at O(\alpha) grows logarithmically in time and is comparable
to that produced from on-shell Compton scattering and pair annihilation at
O(\alpha \alpha_s). Fermion mean fields relax as e^{-\alpha T t ln(\omega_P t)}
with \omega_P=eT/3 the plasma frequency, as a consequence of the emission and
absorption of soft magnetic photons. A quantum kinetic equation for hard
fermions is obtained directly in real time from a field theoretical approach
improved by the dynamical renormalization group. The collision kernel is
time-dependent and infrared finite.

</DOC>
<DOC>
<DOCNO> 84139 </DOCNO>
Exact U(1) symmetric cosmologies with local Mixmaster dynamics


  By applying a standard solution generating technique, we transform an
arbitrary vacuum Mixmaster solution on $S^3 \times {\bf R}$ to a new solution
which is spatially inhomogeneous. We thereby obtain a family of exact,
spatially inhomogeneous, vacuum spacetimes which exhibit Belinskii,
Khalatnikov, and Lifshitz (BKL) oscillatory behavior. The solutions are
constructed explicitly by performing the transformations on numerically
generated, homogeneous Mixmaster solutions. Their behavior is found to be
qualitatively like that seen in previous numerical simulations of generic U(1)
symmetric cosmological spacetimes on $T^3 \times {\bf R}$.

</DOC>
<DOC>
<DOCNO> 122004 </DOCNO>
XMM-Newton observations of the cluster of galaxies Sersic 159-03


  The cluster of galaxies Sersic 159-03 was observed with the XMM-Newton X-ray
observatory as part of the Guaranteed Time program. X-ray spectra taken with
the EPIC and RGS instruments show no evidence for the strong cooling flow
derived from previous X-ray observations. There is a significant lack of cool
gas below 1.5 keV as compared to standard isobaric cooling flow models. While
the oxygen is distributed more or less uniformly over the cluster, iron shows a
strong concentration in the center of the cluster, slightly offset from the
brightness center but within the central cD galaxy. This points to enhanced
type Ia supernova activity in the center of the cluster. There is also an
elongated iron-rich structure extending to the east of the cluster, showing the
inhomogeneity of the iron distribution. Finally, the temperature drops rapidly
beyond 4 arcmin from the cluster center.

</DOC>
<DOC>
<DOCNO> 39908 </DOCNO>
Measurements of spin rotation parameter A in pion-proton elastic


  The ITEP-PNPI collaboration presents the results of the measurements of the
spin rotation parameter A in the elastic scattering of positive and negative
pions on protons at P_beam = 1.62 GeV/c. The setup included a
longitudinally-polarized proton target with superconductive magnet, multiwire
spark chambers and a carbon polarimeter with thick filter. Results are compared
to the predictions of partial wave analyses. The experiment was performed at
the ITEP proton synchrotron, Moscow.

</DOC>
<DOC>
<DOCNO> 122511 </DOCNO>
The DIRTY Model. I. Monte Carlo Radiative Transfer Through Dust


  We present the DIRTY radiative transfer model in this paper and a companion
paper. This model computes the polarized radiative transfer of photons from
arbitrary distributions of stars through arbitrary distributions of dust using
Monte Carlo techniques. The dust re-emission is done self-consistently with the
dust absorption and scattering and includes all three important emission paths:
equilibrium thermal emission, non-equilibrium thermal emission, and the
aromatic features emission. The algorithm used for the radiative transfer
allows for the efficient computation of the appearance of a model system as
seen from any viewing direction. We present a simple method for computing an
upper limit on the output quantity uncertainties for Monte Carlo radiative
transfer models which use the weighted photon approach.

</DOC>
<DOC>
<DOCNO> 101407 </DOCNO>
Topological Entropy of Free Product Automorphisms


  Using free probability constructions involving Cuntz-Pimsner C*-algebras we
show that the topological entropy of the free product of two automorphisms is
equal to the maximum of the individual entropies. As applications we show that
general free shifts have entropy zero. We show that any nuclear C*-dynamical
system admits an entropy preserving covariant embedding into the Cuntz algebra
on infinitely many generators. It follows that any simple nuclear purely
infinite C*-algebra admits an automorphism with any given value of entropy. As
a final application we show that if two automorphisms satisfy a CNT-variational
principle then so does their free product.

</DOC>
<DOC>
<DOCNO> 117855 </DOCNO>
On the Clustering of GRBs on the Sky


  The two-point correlation of the 4th (current) BATSE catalog (2494 objects)
is calculated. It is shown to be consistent with zero at nearly all angular
scales of interest. Assuming that GRBs trace the large scale structure in the
universe we calculate the angular correlation function for the standard CDM
(sCDM) model. It is shown to be $\le 10^{-4}$ at $\theta \simeq 5^\circ$ if the
BATSE catalog is assumed to be a volume-limited sample up to $z \simeq 1$.
Combined with the error analysis on the BATSE catalog this suggests that nearly
$10^5$ GRBs will be needed to make a positive detection of the two-point
angular correlation function at this angular scale.

</DOC>
<DOC>
<DOCNO> 169816 </DOCNO>
Coordinate Independence of of Quantum-Mechanical Path Integrals


  We develop simple rules for performing integrals over products of
distributions in coordinate space. Such products occur in perturbation
expansions of path integrals in curvilinear coordinates, where the interactions
contain terms of the form dot q^2 q^n, which give rise to highly singular
Feynman integrals. The new rules ensure the invariance of perturbatively
defined path integrals under coordinate transformations.

</DOC>
<DOC>
<DOCNO> 11731 </DOCNO>
Atomic four-wave mixing: fermions versus bosons


  We compare the efficiency of four-wave mixing in quantum degenerate gases of
bosonic and fermionic atoms. It is shown that matter-wave gratings formed from
either bosonic or fermionic atoms can in principle exhibit nearly identical
Bragg-scattering, i.e. four-wave mixing, properties. This implies that effects
such as coherent matter-wave amplification and superradiance can occur in
degenerate fermi gases. While in the boson case the Bragg resonance is clearly
due to `Bose enhancement', in the case of fermions the resonance is due to
constructive many-particle quantum interference.

</DOC>
<DOC>
<DOCNO> 121433 </DOCNO>
Using the COBE/DMR data as a test-bed for normality assessments


  A very important property of a statistical distribution is to know whether it
obeys Gaussian statistics or not. On the one hand, it is of paramount
importance in the context of CMB anisotropy studies, since deviations from a
Gaussian distribution could indicate the presence of uncorrected measurement
systematics, of remaining fluctuations contributed by foregrounds, of
deviations from the simplest models of inflation or of topological defects. On
the other hand, looking for a non-Gaussian signal is a very ill-defined task
and performances of various assessment methods may differ widely when applied
in different contexts.
  In previous studies, we introduced a sensitive wavelet-based method which we
apply here to the COBE/DMR data set, already extensively studied, using
different approaches. This provides an objective way to compare methods. It
turns out that our multi-scale wavelet decomposition is a sensitive method. Yet
we show that the results are rather sensitive to the choice of both the
decomposition scheme and the wavelet basis. We find that the detection of the
non-Gaussian signature is ``marginal'' with a probability of at most 99%.

</DOC>
<DOC>
<DOCNO> 116971 </DOCNO>
Development of a DTL Quadrupole Magnet with a New Electroformed Hollow


  Quadrupole electromagnets have been developed with a hollow coil produced
using an improved periodic reverse electroforming. These will be installed in
each of the drift tubes of the DTL (324 MHz) as part of the JAERI/KEK Joint
Project at the high-intensity proton accelerator facility. Measurements of the
magnets' properties were found to be consistent with computer-calculated
estimated. The details of the design, the fabrication process, and the
measurement results for the quadrupole magnet are described.

</DOC>
<DOC>
<DOCNO> 152538 </DOCNO>
Superspace interpretation of mass-dependent BRST symmetries in general


  A superspace formulation is proposed for the osp(1,2)-covariant Lagrangian
quantization of general massive gauge theories. Thereby, osp(1,2) is considered
as subalgebra of the superalgebra sl(1,2) which is interpreted as conformal
algebra acting on two anticommuting coordinates. The mass-dependent (anti)BRST
symmetries of the quantum action in the osp(1,2) superfield formalism are
realized as translations associated by mass-dependent special conformal
transformations.

</DOC>
<DOC>
<DOCNO> 99876 </DOCNO>
On $\alpha ^{++}$-Stable Graphs


  The stability number of a graph G, denoted by alpha(G), is the cardinality of
a stable set of maximum size in G. A graph is well-covered if every maximal
stable set has the same size. G is a Koenig-Egervary graph if its order equals
alpha(G) + mu(G), where mu(G) is the cardinality of a maximum matching in G. In
this paper we characterize $\alpha ^{++}$-stable graphs, namely, the graphs
whose stability numbers are invariant to adding any two edges from their
complements. We show that a K\"{o}nig-Egerv\'{a}ry graph is $\alpha
^{++}$-stable if and only if it has a perfect matching consisting of pendant
edges and no four vertices of the graph span a cycle. As a corollary it gives
necessary and sufficient conditions for $\alpha ^{++}$-stability of bipartite
graphs and trees. For instance, we prove that a bipartite graph is $\alpha
^{++}$-stable if and only if it is well-covered and C4-free.

</DOC>
<DOC>
<DOCNO> 178947 </DOCNO>
Hartree-Fock-Bogoliubov Calculations of the Rotational Band of the Very


  We report on Hartree-Fock-Bogoliubov (HFB) calculations of the ground-state
rotationnal band of the heavy nucleus $^{254}$No recently observed
experimentally. The calculated quadrupole deformation is consistent with the
experimental value of $\beta=0.27$ and is almost constant over the whole band.
We also reproduce fairly well the excitation spectra and moments of inertia of
this isotope up to the maximal experimentally observed state of spin 20. The
rather high stability of this nucleus against fission is illustrated by the
deformation energy curve providing very high fission barriers at zero spin
within the HFB and HFB plus Lipkin-Nogami formalisms. The variation of these
barriers with increased angular velocities is also studied.

</DOC>
<DOC>
<DOCNO> 10059 </DOCNO>
Far-infrared c-axis conductivity of flux-grown


  The far-infrared c-axis conductivity of flux-grown
Y$_{1-x}$Pr$_{x}$Ba$_{2}$Cu$_{3}$O$_{7}$ single crystals with 0.2$\leq $x$\leq
$0.5 has been studied by sepectral ellipsometry. We find that the c-axis
response exhibits spectral features similar to deoxygenated underdoped
YBa$_{2}$Cu$_{3}$O$_{7-\delta}$, i.e., a pseudogap develops in the normal
state, the phonon mode at 320 cm$^{-1}$ exhibits an anomalous T-dependence and
an additional absorption peak forms at T. This suggests that the T$_{c}$
suppression in flux grown Pr-substituted crystals is caused by a decrease of
the hole content and/or by carrier localization rather than by pair breaking.

</DOC>
<DOC>
<DOCNO> 40464 </DOCNO>
Contact interactions in D-brane models


  We compute the tree-level four-point scattering amplitudes in string models
where matter fields live on D-brane intersections. Extracting the contribution
of massless modes, we are left with dimension-six four-fermion operators which
in general receive contributions from three different sources: exchange of
massive Kaluza--Klein excitations, winding modes and string oscillator states.
We compute their coefficients and extract new bounds on the string scale in the
brane-world scenario. This is contrasted with the situation where matter fields
arise from open strings with both ends confined on the same collection of
D-branes, in which case the exchange of massive string modes leads to
dimension-eight operators that have been studied in the past. When matter
fields live on brane intersections, the presence of dimension-six operators
increases the lower bound on the string scale to 2--3 TeV, independently of the
number of large extra dimensions.

</DOC>
<DOC>
<DOCNO> 70836 </DOCNO>
Light quark masses from quenched lattice QCD simulations with domain


  Values for the strange quark mass and average up/down mass have been obtained
from quenched lattice QCD simulations using the domain wall fermion action.
This discretization preserves the properties of flavor and chiral symmetry at
nonzero lattice spacing. Results are shown for two values of the lattice
spacing. The mass renormalization constant is computed nonperturbatively.

</DOC>
<DOC>
<DOCNO> 101201 </DOCNO>
Transitive and Co-Transitive Caps


  A cap in PG(r,q) is a set of points, no three of which are collinear. A cap
is said to be transitive if its automorphism group in PGammaL(r+1,q) acts
transtively on the cap, and co-transitive if the automorphism group acts
transtively on the cap's complement in PG(r,q). Transitive, co-transitive caps
are characterized as being one of: an elliptic quadric in PG(3,q); a
Suzuki-Tits ovoid in PG(3,q); a hyperoval in PG(2,4); a cap of size 11 in
PG(4,3); the complement of a hyperplane in PG(r,2); or a union of Singer orbits
in PG(r,q) whose automorphism group comes from a subgroup of GammaL(1,q^{r+1}).

</DOC>
<DOC>
<DOCNO> 100297 </DOCNO>
Kahler geometry of toric manifolds in symplectic coordinates


  A theorem of Delzant states that any symplectic manifold $(M,\om)$ of
dimension $2n$, equipped with an effective Hamiltonian action of the standard
$n$-torus $\T^n = \R^{n}/2\pi\Z^n$, is a smooth projective toric variety
completely determined (as a Hamiltonian $\T^n$-space) by the image of the
moment map $\phi:M\to\R^n$, a convex polytope $P=\phi(M)\subset\R^n$. In this
paper we show, using symplectic (action-angle) coordinates on $P\times \T^n$,
how all $\om$-compatible toric complex structures on $M$ can be effectively
parametrized by smooth functions on $P$. We also discuss some topics suited for
application of this symplectic coordinates approach to K\"ahler toric geometry,
namely: explicit construction of extremal K\"ahler metrics, spectral properties
of toric manifolds and combinatorics of polytopes.

</DOC>
<DOC>
<DOCNO> 170515 </DOCNO>
Theory of the Quantum Speed Up


  Insofar as quantum computation is faster than classical, it appears to be
irreversible. In all quantum algorithms found so far the speed-up depends on
the extra-dynamical irreversible projection representing quantum measurement.
Quantum measurement performs a computation that dynamical computation cannot
accomplish as efficiently.

</DOC>
<DOC>
<DOCNO> 152546 </DOCNO>
Goldstone-Soliton Interactions and Brane World Neutrinos


  We discuss the interactions of Goldstone particles with solitonic states. We
observe that, contrary to the familiar situation in the vacuum sector, the
Goldstone particles can have non-derivative interactions with the solitons.
This result is applied to brane physics and in particular leads to the
possibility that neutrinos in brane world scenarios are Goldstone particles for
broken supersymmetry.

</DOC>
<DOC>
<DOCNO> 118089 </DOCNO>
Point source models for the gravitational lens B1608+656: Indeterminacy


  We apply elliptical isothermal mass models to reproduce the point source
properties, i.e. image positions, flux density ratios and time delay ratios, of
the quadruple lens B1608+656. A wide set of suitable solutions is found,
showing that models that only fit the properties of point sources are
under-constrained and can lead to a large uncertainty in the prediction of Ho.
We present two examples of models predicting Ho=100 km/(s Mpc) (chi^2=4) and
Ho=69 km/(s Mpc) (chi^2=24).

</DOC>
<DOC>
<DOCNO> 116384 </DOCNO>
Magnetic Field Dependence of Ultracold Inelastic Collisions near a


  Inelastic collision rates for ultracold $^{85}$Rb atoms in the F=2 m$_{f}$=-2
state have been measured as a function of magnetic field. Dramatic change in
the vicinity of a Feshbach resonance at 155 G was observed. Similar to the
elastic rate, the inelastic rates show a high peak and a deep trough. Both two-
and three-body processes are important, and individual contributions have been
determined and compared with theory. This work has made it possible to create
an $^{85}$Rb Bose-Einstein condensate with a highly adjustable scattering
length.

</DOC>
<DOC>
<DOCNO> 40063 </DOCNO>
Limit on Lorentz and CPT Violation of the Neutron Using a Two-Species


  A search for sidereal variations in the frequency difference between
co-located 129-Xe and 3-He Zeeman masers sets the most stringent limit to date
on leading-order Lorentz and CPT violation involving the neutron, consistent
with no effect at the level of 10^{-31} GeV.

</DOC>
<DOC>
<DOCNO> 151811 </DOCNO>
Homogeneous Modes of Cosmological Instantons


  We discuss the O(4) invariant perturbation modes of cosmological instantons.
These modes are spatially homogeneous in Lorentzian spacetime and thus not
relevant to density perturbations. But their properties are important in
establishing the meaning of the Euclidean path integral. If negative modes are
present, the Euclidean path integral is not well defined, but may nevertheless
be useful in an approximate description of the decay of an unstable state. When
gravitational dynamics is included, counting negative modes requires a careful
treatment of the conformal factor problem. We demonstrate that for an
appropriate choice of coordinate on phase space, the second order Euclidean
action is bounded below for normalized perturbations and has a finite number of
negative modes. We prove that there is a negative mode for many gravitational
instantons of the Hawking-Moss or Coleman-De Luccia type, and discuss the
associated spectral flow. We also investigate Hawking-Turok constrained
instantons, which occur in a generic inflationary model. Implementing the
regularization and constraint proposed by Kirklin, Turok and Wiseman, we find
that those instantons leading to substantial inflation do not possess negative
modes. Using an alternate regularization and constraint motivated by reduction
from five dimensions, we find a negative mode is present. These investigations
shed new light on the suitability of Euclidean quantum gravity as a potential
description of our universe.

</DOC>
<DOC>
<DOCNO> 178871 </DOCNO>
Nonexistence of a $\eta NN$ quasibound state


  We have solved the Faddeev equations for $\eta d$ elastic scattering using
realistic separable interactions for the $NN$ and coupled $\eta N$-$\pi N$
subsystems. We found that including explicitly the pion channel in the integral
equations drastically reduces the attraction that is present in the system. As
a consequence, the existence of a $\eta NN$ quasibound state is excluded by the
modern $\eta N$ amplitude analysis.

</DOC>
<DOC>
<DOCNO> 40237 </DOCNO>
Light Axion within the Next-to-Minimal Supersymmetric Standard Model


  We analyze the Higgs sector in the Next-to-Minimal Supersymmetric Standard
Model, emphasizing the possibility of a light CP-odd scalar (axion) in the
spectrum. We compute the coupling of the Standard-Model-like Higgs boson to a
pair of axions, and show that it can be large enough to modify the Higgs
branching fractions, with a significant impact on the Higgs searches. We
delineate the range of parameters relevant for this scenario, and also derive
analytic expressions for the scalar masses and couplings in two special cases -
a decoupling limit where all scalars other than the axion are heavier than the
Standard-Model-like Higgs boson, and the large tan beta limit.

</DOC>
<DOC>
<DOCNO> 100338 </DOCNO>
Full asymptotic expansion of the heat trace for non-self-adjoint


  The operator $e^{-tA}$ and its trace are investigated in the case when $A$ is
a non-self-adjoint elliptic differential operator on a manifold with conical
singularities. Under a certain spectral condition (parameter-ellipticity) we
obtain a full asymptotic expansion in $t$ of the heat trace as $t\to 0^+$. As
in the smooth compact case, the problem is reduced to the investigation of the
resolvent $(A-\lambda)^{-1}$. The main step will consist in approximating this
operator family by a parametrix to $A-\lambda$ using a suitable
parameter-dependent calculus.

</DOC>
<DOC>
<DOCNO> 116912 </DOCNO>
Physics Design of the ETA-II/Snowtron Double Pulse Target Experiment


  We have modified the single pulse target experimental facility[ ] on the
Experimental Test Accelerator II (ETA-II) to perform the double pulse target
experiments to validate the DARHT-II[, ] multi-pulse target concept. The 1.15
MeV, 2 kA Snowtron injector will provide the first electron pulse. The 6 MeV, 2
kA ETA-II beam will be used as the probe beam. Our modeling indicates that the
ETA-II/Snowtron experiment is a reasonable scaling experiment.

</DOC>
<DOC>
<DOCNO> 68966 </DOCNO>
The $\eta_c\gamma \gamma ^*$ transition form factor in the decay


  The Dalitz distribution and the effective mass spectrum of the lepton pair
produced in the decay $\eta_c\to \gamma \ell^+ \ell^-$, as well as the
differential cross sections for the crossed channels $\gamma e^-\to \eta_c e^-
$ and $e^+ e^-\to \eta_c \gamma$, are calculated in terms of the sole
electromagnetic transition form factor for the vertex $\eta_c\to\gamma
\gamma^*$, where $\gamma^*$ is a virtual photon with a space-like (for $\gamma
e^- \to \eta_c e^- $) or a time-like (for $e^+ e^-\to \eta_c \gamma$ and
$\eta_c\to\gamma \ell^+\ell^-$) four-momentum. Explicit parametrisations of the
transition form factor are found in two different approaches, namely in Vector
Dominance Model and in a QCD-inspired consideration on the basis of the process
$c \bar{c}\to \gamma \ell^+ \ell^-$, with zero relative three-momentum of the
annihilating quarks.

</DOC>
<DOC>
<DOCNO> 72173 </DOCNO>
Polarization of Upsilon(nS) at the Tevatron


  The polarization of inclusive Upsilon(nS) at the Fermilab Tevatron is
calculated within the nonrelativistic QCD factorization framework. We use a
recent determination of the NRQCD matrix elements from fitting the CDF data on
bottomonium production from Run IB of the Tevatron. The result for the
polarization of Upsilon(1S) integrated over the transverse momentum bin 8 < p_T
< 20 GeV is consistent with a recent measurement by the CDF Collaboration. The
transverse polarization of Upsilon(1S) is predicted to increase steadily for
p_T greater than about 10 GeV. The Upsilon(2S) and Upsilon(3S) are predicted to
have significantly larger transverse polarizations than Upsilon(1S).

</DOC>
<DOC>
<DOCNO> 102167 </DOCNO>
Explicit constructions in discrete valuations


  In this paper we give an explicit construction of a system of parametric
equations describing a discrete valuation over $k((X_1,...,X_n))$. This amounts
to finding a parameter and a field of coefficients. We devote section 1 to
finding an element of value 1, that is, the parameter. The field of
coefficients is the residue field of the valuation, and it is explicitly
constructed in section 2. As a consequence of this constrution, at the end of
this section, we prove that $k((X_1,...,X_n))$ can be embedded into a field
$L((X_1,...,X_n))$, where the "extended valuation" is as close as posible to
the usual order function.

</DOC>
<DOC>
<DOCNO> 40308 </DOCNO>
Bose-Einstein Correlations in W-pair evets at LEP


  An overview of measurements of Bose-Einstein correlations in W-pair events at
LEP is given. The results presented are based on data collected at
centre-of-mass energies between 172 and 202GeV. The review concentrates on the
search for Bose-Einstein correlations between pions from different W's in e+e-
-> W+W- -> qqbarqqbar events. No agreement is reached in the results of the
four experiments.

</DOC>
<DOC>
<DOCNO> 83252 </DOCNO>
Geometric Morphology of Granular Materials


  We present a new method to transform the spectral pixel information of a
micrograph into an affine geometric description, which allows us to analyze the
morphology of granular materials. We use spectral and pulse-coupled neural
network based segmentation techniques to generate blobs, and a newly developed
algorithm to extract dilated contours. A constrained Delaunay tesselation of
the contour points results in a triangular mesh. This mesh is the basic
ingredient of the Chodal Axis Transform, which provides a morphological
decomposition of shapes. Such decomposition allows for grain separation and the
efficient computation of the statistical features of granular materials.

</DOC>
<DOC>
<DOCNO> 122604 </DOCNO>
What May We Learn from Multi-wavelength Observations of Active Galactic


  We discuss how several of the questions that remain unclear on the physics of
Active Galactic Nuclei may find elements of answers when using in the coming
years the extraordinary set of instruments that will be flying simultaneously
to observe in all bands of the electromagnetic spectrum.
 The choice of questions mentioned here is personal and not exhaustive.

</DOC>
<DOC>
<DOCNO> 122784 </DOCNO>
Timescales of Disk Evolution and Planet Formation


  It has been suggested that circumstellar disks evolve from dense, actively
accreting structures to low-mass, replenished remnants. During this transition,
grains may assemble into planetesimals, or the disk may be cleared by newborn
planets. Recently identified nearby groups of young stars provide valuable
laboratories for probing disk evolution. I discuss the properties of dust disks
in the TW Hydrae Association and the MBM 12 cloud, and compare the results to
other studies of disk evolution and planet formation timescales.

</DOC>
<DOC>
<DOCNO> 116265 </DOCNO>
Path-integral evolution of multivariate systems with moderate noise


  A non Monte Carlo path-integral algorithm that is particularly adept at
handling nonlinear Lagrangians is extended to multivariate systems. This
algorithm is particularly accurate for systems with moderate noise.

</DOC>
<DOC>
<DOCNO> 11888 </DOCNO>
Long-range order and low-energy spectrum of diluted 2D quantum AF


  The problem of diluted two-dimensional (2D) quantum antiferromagnet (AF) on a
square lattice is studied using spin-wave theory. The influence of impurities
on static and dynamic properties is investigated and a good agreement with
experiments and Monte Carlo (MC) data is found. The hydrodynamic description of
spin-waves breaks down at characteristic wavelengths
$\Lambda\agt\exp(\frac{const}{x})$, $x$ being an impurity concentration, while
the order parameter is free from anomalies. We argue that this dichotomy
originates from strong scattering of the low-energy excitations in 2D.

</DOC>
<DOC>
<DOCNO> 118305 </DOCNO>
Formation of Disk Galaxies: On the Angular Momentum Problem, the


  Two ways of possibly solving the angular momentum problem plaguing cold dark
matter (CDM) ab initio simulations of disk galaxy formation are discussed: 1)
Stellar feedback processes and 2) Warm dark matter (WDM) rather than CDM.
  In relation to the chemical evolution of disk galaxies our simulations
indicate that in case 1) the first generation of disk stars formed in disk
galaxies like the Milky Way should have an abundance about two dex below solar,
in fairly good agreement with the lowest observed abundance of the metal-weak
tail of the Galactic thick disk. For the second case no such statements can be
made without further assumptions about the star-formation history of the
galaxies.
  We find that the I-band Tully-Fisher relation can be matched by WDM disk
galaxy formation simulations provided (M/L_I) is about 0.8 for disk galaxies,
which Sommer-Larsen & Dolgov (1999) argue is a reasonable value.
  Finally it is discussed how the magnetic field strengths observed in galactic
disks can be obtained through disk galaxy formation, as an alternative to the
conventional dynamo hypothesis.

</DOC>
<DOC>
<DOCNO> 10334 </DOCNO>
Algorithmic Complexity of Real Financial Markets


  A new approach to the understanding of the complex behavior of financial
markets index using tools from thermodynamics and statistical physics is
developed. Physical complexity, a magnitude rooted in the Kolmogorov-Chaitin
theory is applied to binary sequences built up from real time series of
financial markets indices. The study is based on NASDAQ and Mexican IPC data.
Different behaviors of this magnitude are shown when applied to the intervals
of series placed before crashes and in intervals when no financial turbulence
is observed. The connection between our results and The Efficient Market
Hypothesis is discussed.

</DOC>
<DOC>
<DOCNO> 9367 </DOCNO>
Modified BCS mechanism of Cooper pair formation in narrow energy bands


  In part I of this paper a modified BCS mechanism of Cooper pair formation of
electrons was proposed. This mechanism is connected with the existence of a
narrow, roughly half-filled "superconducting energy band" of given symmetry.
The special symmetry of the superconducting band was interpreted within a
nonadiabatic extension of the Heisenberg model of magnetism. Within this
nonadiabatic Heisenberg model, the electrons of the superconducting band are
constrained to form Cooper pairs at zero temperature because in any normal
conducting state the conservation of crystal-spin angular momentum would be
violated. Except for this participation of the angular momentum, the pair
formation is mediated in the familiar way by phonons. Superconducting bands can
be identified even within a free-electron band structure. Therefore, in this
paper the band structures of the bcc and hcp solid solution alloys composed of
transition elements are approximated by appropriate free-electron band
structures with s-d symmetry. From the free-electron bands, the number n of
valence electrons per atom related to the maxima of the superconducting
transition temperature Tc in these solid solutions is calculated within the
nonadiabatic Heisenberg model. The observed two maxima of Tc are reproduced
without any adjustable parameter at valence numbers n approximately equal to
4.9 and 6.5 in bcc and 4.7 and 6.7 in hcp solid solutions. This result is in
good aggreement with the measured values of 4.7 and 6.4 of Hulm and Blaugher.
The upper maximum is predicted not to exist in bcc transition elements but to
occur in several ordered structures of bcc solid solution alloys.

</DOC>
<DOC>
<DOCNO> 117120 </DOCNO>
Measuring and Controlling the Energy Spread in CEBAF


  As compared to electron storage rings, one advantage of recirculating linear
accelerators is that the beam properties at target are no longer dominated by
the equilibrium between quantum radiative diffusion and radiation damping
because new beam is continually injected into the accelerator. This allows the
energy spread from a CEBAF-type machine to be relatively small; the measured
energy spread from CEBAF at 4 GeV is less than 100 parts per million
accumulated over times of order several days. In this paper, the various
subsystems contributing to the energy spread of a CEBAF-type accelerator are
reviewed, as well as the machine diagnostics and controls that are used in
CEBAF to ensure that a small energy spread is provided during routine running.
Examples of relevant developments are (1) stable short bunches emerging from
the injector, (2) precision timing and phasing of the linacs with respect to
the centroid of the beam bunches on all passes, (3) implementing 2 kHz sampling
rate feedback systems for final energy stabilization, and (4) continuous beam
energy spread monitoring with optical transition radiation devices. We present
measurement results showing that small energy spreads are achieved over
extended periods.

</DOC>
<DOC>
<DOCNO> 151659 </DOCNO>
Mass generation from tachyon condensation for vector fields on D-branes


  The level truncation approach to string field theory is used to study the
zero-momentum action for vector excitations on a bosonic D-brane which has been
annihilated by tachyon condensation. It is shown that in the true vacuum the
translation zero modes associated with transverse scalars on the D-brane are
lifted by spontaneous generation of mass terms. Similarly, the U(1) gauge field
on the brane develops a nonzero mass term.

</DOC>
<DOC>
<DOCNO> 102223 </DOCNO>
Realizable monotonicity and inverse probability transform


  A system (P_a: a in A) of probability measures on a common state space S
indexed by another index set A can be ``realized'' by a system (X_a: a in A) of
S-valued random variables on some probability space in such a way that each X_a
is distributed as P_a. Assuming that A and S are both partially ordered, we may
ask when the system (P_a: a in A) can be realized by a system (X_a: a in A)
with the monotonicity property that X_a <= X_b almost surely whenever a <= b.
When such a realization is possible, we call the system (P_a: a in A)
``realizably monotone.'' Such a system necessarily is stochastically monotone,
that is, satisfies P_a <= P_b in stochastic ordering whenever a <= b. In
general, stochastic monotonicity is not sufficient for realizable monotonicity.
However, for some particular choices of partial orderings in a finite state
setting, these two notions of monotonicity are equivalent. We develop an
inverse probability transform for a certain broad class of posets S, and use it
to explicitly construct a system (X_a: a in A) realizing the monotonicity of a
stochastically monotone system when the two notions of monotonicity are
equivalent.

</DOC>
<DOC>
<DOCNO> 68033 </DOCNO>
Solving the Coincidence Problem: Tracking Oscillating Energy


  Recent cosmological observations strongly suggest that the universe is
dominated by an unknown form of energy with negative pressure. Why is this dark
energy density of order the critical density today? We propose that the dark
energy has periodically dominated in the past so that its preponderance today
is natural. We illustrate this paradigm with a model potential and show that
its predictions are consistent with all observations.

</DOC>
<DOC>
<DOCNO> 8634 </DOCNO>
Effective interactions between electric double-layers


  The present review summarizes and assesses recent theoretical and
experimental advances, with special emphasis on the effective interaction
between charge-stabilized colloids, in the bulk or in confined geometries, and
on the ambiguities of defining an effective charge of the colloidal particles.
Some consideration is given to the often neglected discrete solvent effects.

</DOC>
<DOC>
<DOCNO> 72251 </DOCNO>
Supersymmetric structure of spacetime and matter -superon-graviton


  A unified description of spacetime and matter is proposed by using a single
irreducible representation of SO(10) Super-Poincare algebra(SO(10)SPA). All
(observed) elementary particles except the graviton are the (massless)
eigenstates of SO10)SPA composed of fundamental Nambu-Goldstone fermions with
spin 1/2, superons, associating with the spontaneous breakdown of the
supertranslation of the spacetime. The systematic investigations of the
standard model(SM) and SU(5)GUT by using superon diagrams may reveal the
generation structure, the stability of the proton, K-, B-, D- mixings,
CP-violation, the atmospheric and solar neutrino deficits and the absence of
the electroweak lepton-flavor-mixing. The fundamental action of the
superon-graviton model(SGM) for spacetime and matter is proposed, which is
invariant under a new supersymmetry.

</DOC>
<DOC>
<DOCNO> 11682 </DOCNO>
Fragile-strong transitions and polyamorphism in glass former fluids


  A simple model of a glass former fluid, consisting of a bidisperse mixture of
penetrable spheres is studied. The model shows a transition from fragile to
strong behavior as temperature is reduced. This transition is driven by the
competition between the two mechanisms that contribute to diffusivity in the
model: collective rearrangement of particles (responsible for the fragile
behavior), and individual particle motion (which gives rise to the strong
behavior at low temperature). We also observe a maximum of diffusivity as a
function of pressure that can be interpreted within the same framework. The
connection between this behavior and polyamorphism is addressed.

</DOC>
<DOC>
<DOCNO> 116645 </DOCNO>
Quantum Entanglement and Quantum Chromodynamics


  Non-locality or entanglement is an experimentally well established property
of quantum mechanics. Here we study the role of quantum entanglement for higher
symmetry group like $ SU(3_c) $, the gauge group of quantum chromodynamics
(QCD). We show that the hitherto unexplained property of confinement in QCD
arises as a fundamental feature of quantum entanglement in $ SU(3_c) $.

</DOC>
<DOC>
<DOCNO> 118128 </DOCNO>
The Variation of Gas Mass Distribution in Galaxy Clusters: Effects of


  We investigate the origin of the variation of the gas mass fraction in the
core of galaxy clusters, which was indicated by our work on the X-ray
fundamental plane. The adopted model supposes that the gas distribution
characterized by the slope parameter is related to the preheated temperature.
Comparison with observations of relatively hot (~> 3 keV) and low redshift
clusters suggests that the preheated temperature is about 0.5-2 keV, which is
higher than expected from the conventional galactic wind model and possibly
suggests the need for additional heating such as quasars or gravitational
heating on the largest scales at high redshift. The dispersion of the preheated
temperature may be attributed to the gravitational heating in subclusters. We
calculate the central gas fraction of a cluster from the gas distribution,
assuming that the global gas mass fraction is constant within a virial radius
at the time of the cluster collapse. We find that the central gas density thus
calculated is in good agreement with the observed one, which suggests that the
variation of gas mass fraction in cluster cores appears to be explained by
breaking the self-similarity in clusters due to preheated gas. We also find
that this model does not change major conclusions on the fundamental plane and
its cosmological implications obtained in previous papers, which strongly
suggests that not only for the dark halo but also for the intracluster gas the
core structure preserves information about the cluster formation.

</DOC>
<DOC>
<DOCNO> 13150 </DOCNO>
The problem of Coulomb interactions in the theory of the quantum Hall


  We summarize the main ingredients of a unifying theory for abelian quantum
Hall states. This theory combines the Finkelstein approach to localization and
interaction effects with the topological concept of an instanton vacuum as well
as Chern-Simons gauge theory. We elaborate on the meaning of a new symmetry
($\cal F$ invariance) for systems with an infinitely ranged interaction
potential. We address the renormalization of the theory and present the main
results in terms of a scaling diagram of the conductances.

</DOC>
<DOC>
<DOCNO> 68253 </DOCNO>
Ratio of Quark Masses in Duality Theories


  We consider N=2 SU(2) Seiberg-Witten duality theory for models with N_f=2 and
N_f=3 quark flavors. We find that it is possible to have arbitrary large bare
mass ratios between the two or three quarks.

</DOC>
<DOC>
<DOCNO> 102403 </DOCNO>
Index theorem for equivariant Dirac operators on non-compact manifolds


  Let $D$ be a (generalized) Dirac operator on a non-compact complete
Riemannian manifold $M$ acted on by a compact Lie group $G$. Let $v:M -->
Lie(G)$ be an equivariant map, such that the corresponding vector field on $M$
does not vanish outside of a compact subset. These data define an element of
$K$-theory of the transversal cotangent bundle to $M$. Hence a topological
index of the pair $(D,v)$ is defined as an element of the completed ring of
characters of $G$.
   We define an analytic index of $(D,v)$ as an index space of certain
deformation of $D$ and we prove that the analytic and topological indexes
coincide.
  As a main step of the proof, we show that index is an invariant of a certain
class of cobordisms, similar to the one considered by Ginzburg, Guillemin and
Karshon. In particular, this means that the topological index of Atiyah is also
invariant under this class of non-compact cobordisms.
 As an application we extend the Atiyah-Segal-Singer equivariant index theorem
to our non-compact setting. In particular, we obtain a new proof of this
theorem for compact manifolds.

</DOC>
<DOC>
<DOCNO> 100997 </DOCNO>
Necessary and sufficient conditions for differentiability of a function


  The necessary and sufficient conditions for differentiability of a function
of several real variables stated and proved and its ramifications discussed.

</DOC>
<DOC>
<DOCNO> 99354 </DOCNO>
The Orbit Method for Finite Groups of Nilpotency Class Two of Odd Order


  First, I construct an isomorphism between the categories of (topological)
groups of nilpotency class 2 with 2-divisible center and (topological) Lie
rings of nilpotency class 2 with 2-divisible center. That isomorphism allows us
to construct adjoint and coadjoint representations as usual. For a finite group
G of nilpotency class 2 of odd order, I construct a basis in its group algebra
C[G], parameterized by elements of g* so that the elements of coadjoint orbits
form bases of simple two-side ideals of C[G]. That construction gives us a
one-to-one correspondence between G-orbits in g* and classes of equivalence of
irreducible unitary representations of G, implying a very simple character
formula. The properties of that correspondence are similar to the properties of
the analogous correspondence given by Kirillov's orbit method for nilpotent
connected and simply connected Lie groups. The diagram method introduced in my
article 'Diagrams of Representations, math.RT/9803079 (1998)' and my thesis 'A
Combinatorial Approach to Representations of Lie Groups and Algebras,
University of Pennsylvania (1998)' gives us a convenient way to study normal
forms on the orbits and corresponding representations.

</DOC>
<DOC>
<DOCNO> 122319 </DOCNO>
Not enough stellar mass Machos in the Galactic halo


  We present an update of results from the search for microlensing towards the
Large Magellanic Cloud (LMC) by EROS (Experience de Recherche d'Objets
Sombres). We have now monitored 25 million stars over three years. Because of
the small number of observed microlensing candidates (four), our results are
best presented as upper limits on the amount of dark compact objects in the
halo of our Galaxy. We discuss critically the candidates and the possible
location of the lenses, halo or LMC . We compare our results to those of the
MACHO group. Finally, we combine these new results with those from our search
towards the Small Magellanic Cloud as well as earlier ones from the EROS1 phase
of our survey. The combined data is sensitive to compact objects in the broad
mass range $ 10^{-7} - 10 $ solar masses. The derived upper limit on the
abundance of stellar mass MACHOs rules out such objects as the dominant
component of the Galactic halo if their mass is smaller than 2 solar masses.

</DOC>
<DOC>
<DOCNO> 120522 </DOCNO>
Infrared Spectroscopy of Molecular Supernova Remnants


  We present Infrared Space Observatory spectroscopy of sites in the supernova
remnants W28, W44, and 3C391, where blast waves are impacting molecular clouds.
Atomic fine-structure lines were detected from C, N, O, Si, P, and Fe. The S(3)
and S(9) lines of H2 were detected for all three remnants. The observations
require both shocks into gas with moderate (~ 100 /cm3) and high (~10,000 /cm3)
pre-shock densities, with the moderate density shocks producing the ionic lines
and the high density shock producing the molecular lines. No single shock model
can account for all of the observed lines, even at the order of magnitude
level. We find that the principal coolants of radiative supernova shocks in
moderate-density gas are the far-infrared continuum from dust grains surviving
the shock, followed by collisionally-excited [O I] 63.2 and [Si II] 34.8 micron
lines. The principal coolant of the high-density shocks is
collisionally-excited H2 rotational and ro-vibrational line emission. We
systematically examine the ground-state fine structure of all cosmically
abundant elements, to explain the presence or lack of all atomic fine lines in
our spectra in terms of the atomic structure, interstellar abundances, and a
moderate-density, partially-ionized plasma. The [P II] line at 60.6 microns is
the first known astronomical detection. There is one bright unidentified line
in our spectra, at 74.26 microns. The presence of bright [Si II] and [Fe II]
lines requires partial destruction of the dust. The required gas-phase
abundance of Fe suggests 15-30% of the Fe-bearing grains were destroyed. The
infrared continuum brightness requires ~1 Msun of dust survives the shock,
suggesting about 1/3 of the dust mass was destroyed, in agreement with the
depletion estimate and with theoretical models for dust destruction.

</DOC>
<DOC>
<DOCNO> 102386 </DOCNO>
Asymptotic Dynamics of Nonlinear Schrodinger Equations: Resonance


  We consider a linear Schr\"odinger equation with a small nonlinear
perturbation in $R^3$. Assume that the linear Hamiltonian has exactly two bound
states and its eigenvalues satisfy some resonance condition. We prove that if
the initial data is near a nonlinear ground state, then the solution approaches
to certain nonlinear ground state as the time tends to infinity. Furthermore,
the difference between the wave function solving the nonlinear Schr\"odinger
equation and its asymptotic profile can have two different types of decay: 1.
The resonance dominated solutions decay as $t^{-1/2}$. 2. The radiation
dominated solutions decay at least like $t^{-3/2}$.

</DOC>
<DOC>
<DOCNO> 7650 </DOCNO>
Calculated temperature-dependent resistance in low density 2D hole gases


  We calculate the low temperature resistivity in low density 2D hole gases in
GaAs heterostructures by including screened charged impurity and phonon
scattering in the theory. Our calculated resistance, which shows striking
temperature dependent non-monotonicity arising from the competition among
screening, nondegeneracy, and phonon effects, is in excellent agreement with
recent experimental data.

</DOC>
<DOC>
<DOCNO> 119025 </DOCNO>
Discovery of a very luminous megamaser during a radio flare in the


  We report the detection of a new H_2O megamaser in the Seyfert 2 galaxy Mrk
348 with the MPIfR 100 m telescope in Effelsberg. With an apparent isotropic
luminosity of L_H2O ~ 420 L_sun the maser is the third most luminous maser
discovered so far. The detected line is unusually broad (Delta v ~ 130 km/s),
is redshifted by ~130 km/s from the systemic velocity, and is asymmetric with a
pronounced blue wing. While evidence for obscuring material towards the nucleus
of this galaxy was found earlier, this detection is the first direct
observation of molecular material in the vicinity of the AGN. We also searched
for absorption from ammonia (NH_3) and cyclopropenylidene (C_3H_2) against the
bright radio nucleus. The H_2O line was only marginally detected in archival
data indicating that the maser flared recently in conjunction with a huge radio
continuum flare. Continuum and line flux density increased by a factor of
three, suggesting an unsaturated maser. The radio continuum flare has made Mrk
348 the most radio luminous megamaser galaxy known. It is pointed out that
megamaser galaxies contain a rather large fraction of galaxies with prominent
radio cores and it is speculated that the flare in the maser emission in Mrk
348 is related to the flare in the nuclear jet.

</DOC>
<DOC>
<DOCNO> 152386 </DOCNO>
Covariant relativistic quantum theory


  Covariant classical particle dynamics is described, and the associated
covariant relativistic particle quantum mechanics is derived. The invariant
symmetric bracket is defined on the space of quantum amplitudes, and its
relation to a generalized Hamiltonian dynamics and to a covariant Schr\"odinger
type equation is shown. Examples for relativistic potential problems are
solved. Mathematically and physically acceptable probability densities for the
Klein-Gordon equation and for the Dirac equation are derived, and a new
continuity equation for each case is given. The quantum distribution for mass
is discussed, and unambiguous representations of four-velocity and
four-acceleration operators are given.

</DOC>
<DOC>
<DOCNO> 118372 </DOCNO>
The Baryonic Tully-Fisher Relation


  We explore the Tully-Fisher relation over five decades in stellar mass in
galaxies with circular velocities ranging over 30 < Vc < 300 km/s. We find a
clear break in the optical Tully-Fisher relation: field galaxies with Vc < 90
km/s fall below the relation defined by brighter galaxies. These faint galaxies
are however very gas rich; adding in the gas mass and plotting baryonic disk
mass Md = M* + Mg in place of luminosity restores a single linear relation. The
Tully-Fisher relation thus appears fundamentally to be a relation between
rotation velocity and total baryonic mass of the form Md = A Vc^4.

</DOC>
<DOC>
<DOCNO> 122284 </DOCNO>
On the hypothesis of an advection-dominated flow in the core of NGC


  We report the results of a broadband (0.1-100 keV) X-ray observation of the
nearby elliptical galaxy NGC1052, performed with the BeppoSAX observatory. We
confirm the presence of a bright (2-10 keV luminosity ~ 4 x 10^{42} erg/s) and
strongly absorbed (NH ~ 2 x 10^{23} atoms/cm/cm) X-ray source. The flatness of
the X-ray spectrum (photon index ~1.4), the estimated low accretion rate (m-dot
\~ 10^{-4}) and the radio-to-X-ray spectral energy distribution suggest that
this observation may represent the first direct measurement above 10 keV of an
accretion-dominated flow in an elliptical galaxy.

</DOC>
<DOC>
<DOCNO> 9624 </DOCNO>
Ratchet effect in dc SQUIDs


  We analyzed voltage rectification for dc SQUIDs biased with ac current with
zero mean value. We demonstrate that the reflection symmetry in the
2-dimensional SQUID potential is broken by an applied flux and with appropriate
asymmetries in the dc SQUID. Depending on the type of asymmetry, we obtain a
rocking or a simultaneously rocking and flashing ratchet, the latter showing
multiple sign reversals in the mean voltage with increasing amplitude of the ac
current. Our experimental results are in agreement with numerical solutions of
the Langevin equations for the asymmetric dc SQUID.

</DOC>
<DOC>
<DOCNO> 121860 </DOCNO>
Monte-Carlo simulations of thermal/nonthermal radiation from a


  We discuss the space-and-time-dependent Monte Carlo code we have developed to
simulate the relativistic radiation output from compact astrophysical objects,
coupled to a Fokker-Planck code to determine the self-consistent lepton
populations. We have applied this code to model the emission from a magnetized
neutron star accretion shell near the Alfven radius, reprocessing the radiation
from the neutron sar surface. We explore the parameter space defined by the
accretion rate, stellar surface field and the level of wave turbulence in the
shell. Our results are relevant to the emission from atoll sources, soft-X-ray
transient X-ray binaries containing weakly magnetized neutron stars, and to
recently suggested models of accretion-powered emission from anomalous X-ray
pulsars.

</DOC>
<DOC>
<DOCNO> 11234 </DOCNO>
Electromigration of Single-Layer Clusters


  Single-layer atom or vacancy clusters in the presence of electromigration are
studied theoretically assuming an isotropic medium. A variety of distinctive
behaviors distinguish the response in the three standard limiting cases of
periphery diffusion (PD), terrace diffusion (TD), and evaporation-condensation
(EC). A general model provides power laws describing the size dependence of the
drift velocity in these limits, consistent with established results in the case
of PD. The validity of the widely used quasistatic limit is calculated. Atom
and vacancy clusters drift in opposite directions in the PD limit but in the
same direction otherwise. In absence of PD, linear stability analysis reveals a
new type of morphological instability, not leading to island break-down. For
strong electromigration, Monte Carlo simulations show that clusters then
destabilize into slits, in contrast to splitting in the PD limit.
Electromigration affects the diffusion coefficient of the cluster and
morphological fluctuations, the latter diverging at the instability threshold.
An instrinsic attachment-detachment bias displays the same scaling signature as
PD in the drift velocity.

</DOC>
<DOC>
<DOCNO> 123299 </DOCNO>
Are Silicon Nanoparticles an Interstellar Dust Component?


  Silicon nanoparticles (SNPs) have been proposed as the source of the observed
"extended red emission" (ERE) from interstellar dust. We calculate the thermal
emission expected from such particles in a reflection nebula such as NGC 2023,
and in the diffuse interstellar medium (ISM). Pure neutral Si SNPs would emit
at 16.4 micron (um), while Si/SiO2 SNPs (both neutral and charged) produce a
feature at 20 um. Observational upper limits on the 16.4 um and 20 um features
in NGC 2023 impose upper limits of < 1.5 ppm in pure Si SNPs, and or < 0.2 ppm
in Si/SiO2 SNPs. The observed ERE intensity from NGC 2023 then gives a lower
bound on the required photoluminescence efficiency eta. For foreground
extinction A(0.68um) = 1.2, we find eta > 5% for Si SNPs, or eta > 24% for
Si/SiO2 SNPs in NGC 2023. Measurement of the R band extinction toward the
ERE-emitting region could strengthen these lower limits. The ERE emissivity of
the diffuse ISM appears to require > 42% (> 33%) of solar Si abundance in
Si/SiO2 (Si) SNPs. We predict IR emission spectra and show that DIRBE
photometry appears to rule out such high abundances of free-flying SNPs in the
diffuse ISM. If the ERE is due to SNPs, they must be either in clusters or
attached to larger grains. Future observations by SIRTF will be even more
sensitive to the presence of free-flying SNPs.

</DOC>
<DOC>
<DOCNO> 121314 </DOCNO>
The Massive Stellar Population in a Nearby Massive Low Surface


  We have observed the closest known large, low surface brightness (LSB)
galaxy, UGC 2302, with HST using WFPC2 and the F555W and F814W filters. UGC
2302 is a typical large LSB galaxy, and thus represents a good choice for
detailed stellar population studies. Large LSBs represent an extreme star
formation environment, both locally within their disks, and on a larger scale,
often residing in underdense regions of the universe. Resolving the underlying
stellar component of such a galaxy can provide critical information on how
stars form and evolve in low metallicity, yet gas-rich environments. We resolve
for the first time the massive stars and tip of the red giant branch in such a
system.

</DOC>
<DOC>
<DOCNO> 83324 </DOCNO>
Ordering-based Representations of Rational Inference


  Rational inference relations were introduced by Lehmann and Magidor as the
ideal systems for drawing conclusions from a conditional base. However, there
has been no simple characterization of these relations, other than its original
representation by preferential models. In this paper, we shall characterize
them with a class of total preorders of formulas by improving and extending
Gardenfors and Makinson's results for expectation inference relations. A second
representation is application-oriented and is obtained by considering a class
of consequence operators that grade sets of defaults according to our reliance
on them. The finitary fragment of this class of consequence operators has been
employed by recent default logic formalisms based on maxiconsistency.

</DOC>
<DOC>
<DOCNO> 40003 </DOCNO>
Neutron Structure Function and A=3 Mirror Nuclei


  We investigate deep inelastic scattering from He-3 and H-3 within a
conventional convolution treatment of binding and Fermi motion effects. Using
realistic Faddeev wave functions together with a nucleon spectral function, we
demonstrate that the free neutron structure function can be extracted in
deep-inelastic scattering from A=3 mirror nuclei, with nuclear effects
canceling to within 2% for x < 0.85.

</DOC>
<DOC>
<DOCNO> 80947 </DOCNO>
Two-loop Perturbative Quark Mass Renormalization from Large Beta Monte


  We present the calculation of heavy Wilson quark mass renormalization
constants from large beta Monte Carlo simulations. Simulations were performed
at various beta larger than 9, each on several spatial lattice sizes to allow
for an infinite volume extrapolation. We use twisted boundary conditions to
suppress tunneling and work in Coulomb gauge with appropriate adjustments for
the temporal links. The one-loop coefficient obtained from this method is in
agreement with the analytical result and a preliminary result for the second
order coefficient is reported.

</DOC>
<DOC>
<DOCNO> 9766 </DOCNO>
Schr\"odinger cat state of a Bose-Einstein condensate in a double-well


  We consider a weakly interacting coherently coupled Bose-Einstein condensate
in a double-well potential. We show by means of stochastic simulations that the
system could possibly be driven to an entangled macroscopic superposition state
or a Schr\"odinger cat state by means of a continuous quantum measurement
process.

</DOC>
<DOC>
<DOCNO> 178683 </DOCNO>
Calculating the Fierz Transformation for Higher Orders


  We consider the higher-order Fierz transformation, which corresponds to
expanding a product of $\bar\psi\Gamma\psi$ terms into a sum of products of
Dirac densities and currents. It is shown that the Fierz transformation can be
obtained by solving a large system of linear equations with fractional complex
coefficients, which is practical at least up to fourth power.

</DOC>
<DOC>
<DOCNO> 117342 </DOCNO>
The electromagnetic interaction of ultrarelativistic heavy ions


  The validity of a delta-function approximation for the electromagnetic
interaction of relativistic heavy ions is investigated. The production of e+e-
pairs, with electron capture, is used as a test of the approximation.

</DOC>
<DOC>
<DOCNO> 9388 </DOCNO>
Modified group projectors: tight binding method


  Modified group projector technique for induced representations is a powerful
tool for calculation and symmetry quantum numbers assignation of a tight
binding Hamiltonian energy bands of crystals. Namely, the induced type
structure of such a Hamiltonian enables efficient application of the procedure:
only the interior representations of the orbit stabilizers are to be
considered. Then the generalized Bloch eigen functions are obtained naturally
by the expansion to the whole state space. The method is applied to the
electronic pi-bands of the single wall carbon nanotubes: together with
dispersion relations, their complete symmetry assignation by the full symmetry
(line) groups and the corresponding symmetry-adapted eigen function are found.

</DOC>
<DOC>
<DOCNO> 150997 </DOCNO>
Extremal and next-to-extremal n-point correlators in four-dimensional


  It is shown that certain extremal and next-to-extremal n-point correlators in
four-dimensional N=2 superconformal field theories are free. These results hold
for any gauge group.

</DOC>
<DOC>
<DOCNO> 118379 </DOCNO>
Detection of Weak Gravitational Lensing by Large-scale Structure


  We report a detection of the coherent distortion of faint galaxies arising
from gravitational lensing by foreground structures. This ``cosmic shear'' is
potentially the most direct measure of the mass power spectrum, as it is
unaffected by poorly-justified assumptions made concerning the biasing of the
distribution. Our detection is based on an initial imaging study of 14
separated 8' x 16' fields observed in good, homogeneous conditions with the
prime focus EEV CCD camera of the 4.2m William Herschel Telescope. We detect an
rms shear of 1.6% in 8' x 8' cells, with a significance of 3.4 sigma. We
carefully justify this detection by quantifying various systematic effects and
carrying out extensive simulations of the recovery of the shear signal from
artificial images defined according to measured instrument characteristics. We
also verify our detection by computing the cross-correlation between the shear
in adjacent cells. Including (gaussian) cosmic variance, we measure the shear
variance to be (0.016)^2 plus/minus (0.012)^2 plus/minus (0.006)^2, where these
1 sigma errors correspond to statistical and systematic uncertainties,
respectively. Our measurements are consistent with the predictions of
cluster-normalised CDM models (within 1 sigma) but a COBE-normalised SCDM model
is ruled out at the 3.0 sigma level. For the currently-favoured Lambda-CDM
model (with Omega_m = 0.3), our measurement provides a normalisation of the
mass power spectrum of sigma_8 = 1.5 plus/minus 0.5, fully consistent with that
derived from cluster abundances. Our result demonstrates that ground-based
telescopes can, with adequate care, be used to constrain the mass power
spectrum on various scales. The present results are limited mainly by cosmic
variance, which can be overcome in the near future with more observations.

</DOC>
<DOC>
<DOCNO> 122837 </DOCNO>
Why is the Hubble flow so quiet?


  The cosmological vacuum, which is perfectly uniform, dominates by density
over all the forms of cosmic matter. It makes the Universe be actually more
uniform than it could be seen from the visible picture of the highly
non-uniform matter distribution, especially inside the observed cell of
uniformity (100-150 Mpc). This uniformity reveals itself in the structure of
the Hubble matter flow which extends over a giant range of cosmic space scales
-- from few Mpc to a thousand Mpc, -- preserving its kinematical identity.
According to Sandage (1999), this flow is mysteriously regular and quiet even
deep inside the cell of uniformity. An answer we propose to the question in the
title above is as follows: This is most probably because the flow is
dynamically controlled by the cosmological vacuum. An additional conjecture of
cosmological intermittency, that addresses a complex statistical structure of
initial chaotic perturbations, is also suggested in this context.

</DOC>
<DOC>
<DOCNO> 117201 </DOCNO>
A macroscopic approach to creating exotic matter


  Herein the Casimir effect is used to present a simple macroscopic view on
creating exotic matter. The energy arising between two nearly perfectly
conducting parallel plates is shown to become increasingly negative as the
plate separation is reduced. It is proposed that the Casimir energy appears
increasingly negative simply because the vacuum electromagnetic zero-point
field performs positive work in pushing the plates together, transforming field
energy into kinetic energy of the plates. Next, the inertial properties of
exotic matter are considered. The parallel plates of the Casimir system are
replaced with an enclosed cavity of identical dimensions that is subjected to
an external force. It is found that zero-point radiation exerts an inertial
force on the cavity in opposition to the external force. This ultimately leads
to the conclusion that the inertial properties of exotic matter are identical
to the inertial properties of ordinary matter.

</DOC>
<DOC>
<DOCNO> 80655 </DOCNO>
Large N Dynamics of Dimensionally Reduced 4D SU(N) Super Yang-Mills


  We perform Monte Carlo simulations of a supersymmetric matrix model, which is
obtained by dimensional reduction of 4D SU(N) super Yang-Mills theory. The
model can be considered as a four-dimensional counterpart of the IIB matrix
model. We extract the space-time structure represented by the eigenvalues of
bosonic matrices. In particular we compare the large N behavior of the
space-time extent with the result obtained from a low energy effective theory.
We measure various Wilson loop correlators which represent string amplitudes
and we observe a nontrivial universal scaling in N. We also observe that the
Eguchi-Kawai equivalence to ordinary gauge theory does hold at least within a
finite range of scale. Comparison with the results for the bosonic case
clarifies the role of supersymmetry in the large N dynamics. It does affect the
multi-point correlators qualitatively, but the Eguchi-Kawai equivalence is
observed even in the bosonic case.

</DOC>
<DOC>
<DOCNO> 84731 </DOCNO>
External symmetry in general relativity


  We propose a generalization of the isometry transformations to the geometric
context of the field theories with spin where the local frames are explicitly
involved. We define the external symmetry transformations as isometries
combined with suitable tetrad gauge transformations and we show that these form
a group which is locally isomorphic with the isometry one. We point out that
the symmetry transformations that leave invariant the equations of the fields
with spin have generators with specific spin terms which represent new physical
observables. The examples we present are the generators of the central symmetry
and those of the maximal symmetries of the de Sitter and anti-de Sitter
spacetimes derived in different tetrad gauge fixings.
  Pacs: 04.20.Cv, 04.62.+v, 11.30.-j

</DOC>
<DOC>
<DOCNO> 116339 </DOCNO>
The Emergence of the Planck Scale


  In this paper we first observe some interesting parallels between Planck
scale considerations and elementary particle Compton wavelength scale
considerations, particularly in the context of Wheeler's space time foam and a
space time arising out of a stochastic random heap of elementary particles
discussed in previous papers. These parallels lead to a semi qualitative
picture which shows how the short lived Planck scale arises from the Compton
wavelength considerations.

</DOC>
<DOC>
<DOCNO> 117495 </DOCNO>
Origin of Color Gradients in Elliptical Galaxies


  The origin of color gradients in elliptical galaxies is examined by comparing
model gradients with those observed in the Hubble Deep Field. The models are
constructed so as to reproduce color gradients in local elliptical galaxies
either by a metallicity gradient or by an age gradient. By looking back a
sequence of color gradient as a function of redshift, the age - metallicity
degeneracy is solved. The observed color gradients in elliptical galaxies at
$z=0.1-1.0$ agree excellently with those predicted by the metallicity gradient,
while they deviates significantly from those predicted by the age gradient even
at $z \sim 0.3$ and the deviation is getting larger with increasing redshift.
This result does not depend on cosmological parameters and parameters for an
evolutionary model of galaxy within a reasonable range. Thus our results
clearly indicate that the origin of color gradients is not the age but the
stellar metallicity.

</DOC>
<DOC>
<DOCNO> 151989 </DOCNO>
Null Vectors in Logarithmic Conformal Field Theory


  The representation theory of the Virasoro algebra in the case of a
logarithmic conformal field theory is considered. Here, indecomposable
representations have to be taken into account, which has many interesting
consequences. We study the generalization of null vectors towards the case of
indecomposable representation modules and, in particular, how such logarithmic
null vectors can be used to derive differential equations for correlation
functions. We show that differential equations for correlation functions with
logarithmic fields become inhomogeneous.

</DOC>
<DOC>
<DOCNO> 83458 </DOCNO>
Automatic Debugging Support for UML Designs


  Design of large software systems requires rigorous application of software
engineering methods covering all phases of the software process. Debugging
during the early design phases is extremely important, because late bug-fixes
are expensive.
  In this paper, we describe an approach which facilitates debugging of UML
requirements and designs. The Unified Modeling Language (UML) is a set of
notations for object-orient design of a software system. We have developed an
algorithm which translates requirement specifications in the form of annotated
sequence diagrams into structured statecharts. This algorithm detects conflicts
between sequence diagrams and inconsistencies in the domain knowledge. After
synthesizing statecharts from sequence diagrams, these statecharts usually are
subject to manual modification and refinement. By using the ``backward''
direction of our synthesis algorithm, we are able to map modifications made to
the statechart back into the requirements (sequence diagrams) and check for
conflicts there. Fed back to the user conflicts detected by our algorithm are
the basis for deductive-based debugging of requirements and domain theory in
very early development stages. Our approach allows to generate explanations on
why there is a conflict and which parts of the specifications are affected.

</DOC>
<DOC>
<DOCNO> 99826 </DOCNO>
On the degrees of irreducible representations of Hopf algebras


  Let H denote a semisimple Hopf algebra over an algebraically closed field k
of characteristic 0. We show that the degree of any irreducible representation
of H whose character belongs to the center of H^* must divide the dimension of
H .

</DOC>
<DOC>
<DOCNO> 101304 </DOCNO>
Canonical Bases and Piecewise-linear Combinatorics


  Let U be the quantum group associated to a Lie algebra g of rank n. The
negative part U^- of U has a canonical basis B with favourable properties,
introduced by Kashiwara and Lusztig. The approaches of Kashiwara and Lusztig
lead to a set of alternative parametrizations of the canonical basis, one for
each reduced expression for the longest word in the Weyl group of g. We
describe the authors' recent work establishing close relationships between the
Lusztig cones, canonical basis elements and the regions of linearity of
reparametrization functions arising from the above parametrizations in type A_4
and give some speculations for type A_n.
  Keywords: Quantum group, Lie algebra, Canonical basis, Tight monomials, Weyl
group, Piecewise-linear functions.

</DOC>
<DOC>
<DOCNO> 121270 </DOCNO>
A Deep Multicolor Survey. VII. Extremely Red Objects and Galaxy


  Extremely Red Objects (EROs) offer a window to the universe at z~1 analogous
to that provided by the Lyman Break galaxies at z=3. Passive evolution and
hierarchical galaxy formation models make very distinct predictions for the K
(2.2um) surface density of galaxies at z~1 and EROs are a powerful constraint
on these theories. I present a study of nine resolved EROs with R-K>5.3 and
K<18 mag found in the 185 arcmin^2 of the Deep Multicolor Survey with
near-infrared imaging. Photometric redshifts for these galaxies shows they all
lie at z=0.8-1.3. The relatively blue J-K colors of these galaxies suggest that
most are old ellipticals, rather than dusty starbursts. The surface density of
EROs in this survey (>0.05 arcmin^-2), which is a lower limit to the total z~1
galaxy surface density, is an order of magnitude below the prediction of
passive galaxy evolution, yet over a factor of two higher than the hierarchical
galaxy formation prediction for a flat, matter-dominated universe. A flat,
Lambda-dominated universe may bring the hierarchical galaxy formation model
into agreement with the observed ERO surface density.

</DOC>
<DOC>
<DOCNO> 118658 </DOCNO>
Radio continuum emission from the central stars of M20 and the detection


  The Trifid nebula (M20) is a well-known prominent optical HII region
trisected by obscuring dust lanes. Radio continuum VLA observations of this
Nebula show free-free emission at lambda 3.6 and 6cm from three stellar sources
lying close to the O7V star at the center of the nebula. We argue that neutral
material associated with these stars are photoionized externally by the UV
radiation from the hot central star. We also report the discovery of a
barrel-shaped SNR G7.06--0.12 at the northwest rim of the nebula and two
shell-like features G6.67--0.42 and G6.83--0.21 adjacent to W28 and M20. We
discuss the nature of these features and their possible relationship to the
pulsar PSR 1801-2306 and W28 OH (1720 MHz) masers.

</DOC>
<DOC>
<DOCNO> 69296 </DOCNO>
Universal Torsion-Induced Interaction from Large Extra Dimensions


  We consider the Kaluza-Klein (KK) scenario in which only gravity exists in
the bulk. Without the assumption of symmetric connection, the presence of brane
fermions induces torsion. The result is a universal axial contact interaction
that dominates those induced by KK gravitons. This enhancement arises from a
large spin density on the brane. Using a global fit to Z-pole observables, we
find the 3 sigma bound on the scale of quantum gravity to be 28 TeV for n=2. If
Dirac or light sterile neutrinos are present, the data from SN1987A increase
the bound to \sqrt{n}M_S >= 210 TeV.

</DOC>
<DOC>
<DOCNO> 11820 </DOCNO>
Transverse and in-plane modification of superconductivity and electronic


  We have employed uniaxial stress along the principal axes of the quasi-two
dimensional organic superconductor $\kappa $--(BEDT-TTF)$_{2}$Cu(SCN)$_{2}$.
The lattice anisotropy is thereby altered, with corresponding changes in the
intermolecular transfer energies. The effect of uniaxial stress on the
superconducting transition temperature $T_{c}$ and critical field $B_{c2}$ is
found to be anisotropic.There is an indication of an increase in $T_{c}$ and
$B_{c2}$ for in-plane stress, but both parameters decrease rapidly for
transverse (inter-plane) stress. Magnetotransport studies reveal stress-induced
changes in the Fermi surface through the observation of the Shubnikov de Haas
oscillations. The stress dependence of a resistive anomaly in the
magnetoresistance, which is associated with the critical field $B_{c2}$, is
also investigated. We discuss the experimental findings in the context of
recent phenomenological and theoretical treatments of quasi-two dimensional
systems where the anisotropic triangular lattice Hubbard model has been used to
treat two-dimensional superconductors.

</DOC>
<DOC>
<DOCNO> 119185 </DOCNO>
Identification of A-colored Stars and Structure in the Halo of the Milky


  A sample of 4208 objects with magnitude 15 < g* < 22 and colors of main
sequence A stars has been selected from 370 square degrees of Sloan Digital Sky
Survey (SDSS) commissioning observations. The data is from two long, narrow
stripes, each with an opening angle of greater than 60 deg, at Galactic
latitudes 36 < abs(b) < 63 on the celestial equator. An examination of the
sample's distribution shows that these stars trace considerable substructure in
the halo. Large overdensities of A-colored stars in the North at (l,b,R) =
(350, 50, 46 kpc) and in the South at (157, -58, 33 kpc) and extending over
tens of degrees are present in the halo of the Milky Way. Using photometry to
separate the stars by surface gravity, both structures are shown to contain a
sequence of low surface gravity stars consistent with identification as a blue
horizontal branch (BHB). Both structures also contain a population of high
surface gravity stars two magnitudes fainter than the BHB stars, consistent
with their identification as blue stragglers (BSs). From the numbers of
detected BHB stars, lower limits to the implied mass of the structures are
6x10^6 M_sun and 2x10^6 M_sun. The fact that two such large clumps have been
detected in a survey of only 1% of the sky indicates that such structures are
not uncommon in the halo. Simple spheroidal parameters are fit to a complete
sample of the remaining unclumped BHB stars and yield (at r < 40 kpc) a fit to
a halo distribution with flattening (c/a = 0.65+/-0.2) and a density falloff
exponent of alpha = -3.2+/-0.3.

</DOC>
<DOC>
<DOCNO> 11905 </DOCNO>
Integrable boundary impurities in the t-J model with different gradings


  We investigate the generalized supersymmetric $t-J$ model with boundary
impurities in different gradings. All three different gradings: fermion,
fermion, boson (FFB), boson, fermion, fermion (BFF) and fermion, boson, fermion
(FBF), are studied for the generalized supersymmetric $t-J$ model. Boundary
K-matrix operators are found for the different gradings. By using the graded
algebraic Bethe ansatz method, we obtain the eigenvalues and the corresponding
Bethe ansatz equations for the transfer matrix.

</DOC>
<DOC>
<DOCNO> 152400 </DOCNO>
Integrable Many-Body Systems and Gauge Theories


  The review studies connections between integrable many-body systems and gauge
theories. It is shown how the degrees of freedom in integrable systems are
related with topological degrees of freedom in gauge theories. The relations
between families of integrable systems and N=2 supersymmetric gauge theories
are described. It is explained that the degrees of freedom in the many-body
systems can be identified with collective coordinates of D-branes, solitons in
string theory.

</DOC>
<DOC>
<DOCNO> 101158 </DOCNO>
Topological Insights from the Chinese Rings


  L. Kauffman conjectured that a particular solution of the Chinese Rings
puzzle is the simplest possible. We prove his conjecture by using
low-dimensional topology and group theory. We notice also a surprising
connection between the Chinese Rings and Habiro moves (related to Vassiliev
invariants).

</DOC>
<DOC>
<DOCNO> 102556 </DOCNO>
Topological classification of Z_{p}^{m} actions on surfaces


  Let $\widetilde{S}$ be a closed (compact without boundary) oriented surface
with genus $g$, and $G$ be a group isomorphic to $% \mathbf{Z}_{p}^{m}$, where
$p$ is a prime integer. An action of $G$ on $S$ is a pair $(\widetilde{S},f)$,
where $f$ is a representation of $G$ in the group of orientation preserving
autohomeomorphisms of $\widetilde{S}$. Two actions $(\widetilde{S},f)$ and
$(\widetilde{S^{\prime}},f^{\prime})$ are called strongly (resp. weakly)
equivalent if there is a homeomorphism$,$ $% \widetilde{\psi}:\widetilde{S}\to
\widetilde{S}^{\prime},$ sending the orientation of $\widetilde{S}$ to the
orientation of $\widetilde{S}% ^{\prime},$ such that
$f^{\prime}(h)=\widetilde{\psi}\circ f(h)\circ \widetilde{\psi}^{-1},$ (resp.
there is an automorphism $\alpha \in Aut(G)$ such that $f^{\prime}\circ \alpha
(h)=\widetilde{\psi}\circ f(h)\circ \widetilde{\psi}^{-1}$) for all $h\in G.$
We give the full description of strong and weak equivalence classes. The main
idea of our work is the fact that a fixed point free action of
$\mathbf{Z}_{p}^{m}$ on a surface provides a bilinear antisymmetric form on
$\mathbf{Z}_{p}^{m}.$ For instance, we prove that the weakly equivalence
classes of actions of $G$ on surfaces with orbit space of genus $g$ are in one
to one correspondence with the set of pairs which consist in a positive integer
number $k$, $k\leq m-n,$ $k=(m-n)% \func{mod}2,$ $g\geq {1/2}(m-n+k),$ and an
orbit of the action of $% Aut(G)$ on the set of unordered $r$-tuples
$[C_{1},...,C_{r}]$ of non-trivial elements generating a subgroup isomorphic to
$\mathbf{Z}_{p}^{n}$ and such that $\sum_{1}^{r}C_{i}=0$. We use this result in
describing the moduli space of complex algebraic curves admitting a group of
automorphisms isomorphic to $\mathbf{Z}_{p}^{m}.$

</DOC>
<DOC>
<DOCNO> 7761 </DOCNO>
Incommensurate and Commensurate Antiferromagnetic Spin Fluctuations in


  A scheme for making ab-initio calculations of the dynamic paramagnetic spin
susceptibilities of solids at finite temperatures is described. It is based on
Time-Dependent Density Functional Theory and employs an electronic multiple
scattering formalism. Incommensurate and commensurate anti-ferromagnetic spin
fluctuations in paramagnetic Cr and compositionally disordered Cr95V5 and
Cr95Re5 alloys are studied together with the connection with the nesting of
their Fermi surfaces. We find that the spin fluctuations can be described
rather simply in terms of an overdamped oscillator model. Good agreement with
inelastic neutron scattering data is obtained.

</DOC>
<DOC>
<DOCNO> 117916 </DOCNO>
Mode identification from line-profile variations


  We review the current status of different mode-identification techniques
based on observed line-profile variations. Three basic methods are currently
available to identify the non-radial pulsation modes. These three methods are
described, together with their different variants. We further present
applications to real data, focusing especially on delta Scuti stars. After
having discussed all the methods and their applications, we present an
inventory in which we compare the properties of the different methods. Finally,
we end with future prospects, both on the theoretical and observational side.

</DOC>
<DOC>
<DOCNO> 119521 </DOCNO>
BLR velocities in optically and X-ray selected AGN samples


  We have analyzed optical spectra of 473 X-ray and 235 optically selected
AGNs, to study their emission line properties. We present results of an
analysis of the H-beta linewidths. We find that the linewidth distribution of
quasars is shifted towards higher velocities (<v>=4300 km s-1) compared to the
distribution of Sy 1s (<v>=3000 km s-1). There are no Narrow Line Quasars, i.e.
there are no AGNs with quasar luminosities and FWHM(H-beta) < 2000 km s-1.
NLSy1s comprise 20-30 per cent of the AGN population at faint absolute
magnitudes (MB>-22), irrespective of the selection method. In the RASS sample
we find Gamma [0.1-2.4 keV] < 3.3. The Gamma vs. FWHM(H-beta) distribution for
Sy 1 galaxies is consistent with previous work. For QSOs the spectral index
also flattens with increasing FWHM(H-beta), but they have larger linewidths
than Seyfert 1s.

</DOC>
<DOC>
<DOCNO> 101728 </DOCNO>
On triangleleft^*-maximality


  This paper investigates a connection between the ordering triangleleft^ast
among theories in model theory and the (N)SOP_n hierarchy of Shelah. It
introduces two properties which are natural extensions of this hierarchy,
called SOP_2 and SOP_1, and gives a strong connection between SOP_1 and the
maximality in Keisler ordering. Together with the known results about the
connection between the (N)SOP_n hierarchy and the existence of universal models
in the absence of GCH, the paper provides a step toward the classification of
unstable theories without the strict order property.

</DOC>
<DOC>
<DOCNO> 117596 </DOCNO>
Induction of supernova-like explosions by gamma-ray bursts in close


  We propose that a gamma-ray burst in one member of a binary may induce a
supernova-like explosion of a close, white-dwarf companion. Such an explosion
might be brought about in rather light companions, which cannot undergo the
standard accretion-induced explosion. This would give some GRB-associated
supernova an appearance rather unlike that of the typical Type I. GRB 980425,
if indeed associated with SN 1998bw, is too weak to have produced it through
our proposed mechanism.

</DOC>
<DOC>
<DOCNO> 169565 </DOCNO>
Modification of relative entropy of Entanglement


  We present the modified relative entropy of entanglement (MRE) in order to
both improve the computability for the relative entropy of entanglement and
avoid the problem that the entanglement of formation seems to be greater than
entanglement of distillation. For two qubit system we derive out an explicit
and "weak" closed expression of MRE that depends on the pure state
decompositions in the case of mixed states. For more qubit system, we obtain an
algorithm to calculate MRE in principle. MRE significantly improves the
computability of relative entropy of entanglement and decreases the dependence
and sensitivity on the pure state decompositions. Moreover it is able to
inherit most of the important physical features of the relative entropy of
entanglement. In addition, a kind of states, as an extension of Werner's
states, is discussed constructively.

</DOC>
<DOC>
<DOCNO> 9283 </DOCNO>
The "topological" charge for the finite XX quantum chain


  It is shown that an operator (in general non-local) commutes with the
Hamiltonian describing the finite XX quantum chain with certain non-diagonal
boundary terms. In the infinite volume limit this operator gives the
"topological" charge.

</DOC>
<DOC>
<DOCNO> 121055 </DOCNO>
A Near-Infrared Photometric Survey of Metal-Poor Inner Spheroid Globular


  Images recorded through J, H, K, 2.2 micron continuum and CO filters have
been obtained of a sample of metal-poor ([Fe/H] < -1.3) globular clusters in
the inner spheroid of the Galaxy. The shape and color of the upper giant branch
on the (K, J-K) CMD, combined with the K brightness of the RGB-tip, are used to
estimate the metallicity, reddening, and distance of each cluster. CO indices
are used to identify bulge stars, which will bias metallicity and distance
estimates if not removed from the data. Bulge fields were also observed near
each cluster. The slope of the bulge giant branch luminosity function does not
vary between most fields, although the LFs in Baade's Window and near NGC 6273
are significantly shallower than average. The data also suggest that the HB
content may not be uniform throughout the bulge, in the sense that a larger
than average number of red HB stars may occur in fields closest to the Galactic
Center.

</DOC>
<DOC>
<DOCNO> 122190 </DOCNO>
The Universe Traced by Clusters


  I critically review a methodology of using clusters of galaxies as
cosmological probes. The understanding of the abundances and spatial
correlations of dark matter halos has been significantly advanced especially
for a last few years. Nevertheless such dark matter halos are not necessarily
identical to clusters of galaxies in the universe. This is a quite obvious
fact, but it seems that the resulting systematic errors, on the cosmological
parameter estimates for instance, are often neglected in the literature.

</DOC>
<DOC>
<DOCNO> 117981 </DOCNO>
The Optical Gravitational Lensing Experiment. Catalog of Microlensing


  We present the Catalog of microlensing events detected toward the Galactic
bulge in three observing seasons, 1997--1999, during the OGLE-II microlensing
survey. The search for microlensing events was performed using a database of
about 4*10^9 photometric measurements of about 20.5 million stars from the
Galactic bulge. The Catalog comprises 214 cases of microlensing events found in
the fields covering about 11 square degrees on the sky and distributed in
different parts of the Galactic bulge. The sample includes 20 binary
microlensing events, 14 of them are caustic crossing. In one case a double star
is likely lensed.
  We present distribution of the basic parameters of microlensing events and
show preliminary rate of microlensing in different regions of the Galactic
bulge. The latter reveals clear dependence on the Galactic coordinates. The
dependence on 'l' indicates that the majority of lenses toward the Galactic
bulge are located in the Galactic bar. Models of the Galactic bar seem to
reasonably predict the observed spatial distribution of microlensing events in
the Galactic bulge.
  All data presented in the Catalog and photometry of all events are available
from the OGLE Internet archive.

</DOC>
<DOC>
<DOCNO> 150420 </DOCNO>
Double Elliptic Systems: Problems and Perspectives


  This talk presents a list of problems related to the double-elliptic (Dell)
integrable systems with elliptic dependence on both momenta and coordinates. As
expected, in the framework of Seiberg-Witten theory the recently discovered
explicit self-dual family of 2-particle Dell Hamiltonians provides a
perturbative period matrix which is a logarithm of the ratio of the
(momentum-space) theta-functions.

</DOC>
<DOC>
<DOCNO> 122465 </DOCNO>
High Energy Neutrino Astronomy - the cosmic-ray connection


  Several of the models for origin of the highest energy cosmic rays also
predict significant neutrino fluxes. A common factor of the models is that they
must provide sufficient power to supply the observed energy in the
extragalactic component of the cosmic radiation. The assumption that a
comparable amount of energy goes into high-energy neutrinos allows a
model-independent estimate of the neutrino signal that may be expected.

</DOC>
<DOC>
<DOCNO> 9735 </DOCNO>
Landau Model for Commensurate-Commensurate Phase Transitions in Uniaxial


  We propose the Landau model for lock-in phase transitions in uniaxially
modulated improper ferroelectric incommensurate-commensurate systems of class
I. It includes Umklapp terms of third and fourth order and secondary order
parameter representing the local polarization. The corresponding phase diagram
has the structure of harmless staircase, with the allowed wave numbers obeying
the Farey tree algorithm. Among the stable commensurate phases only those with
periods equal to odd number of lattice constants have finite macroscopic
polarizations. These results are in excellent agreement with experimental
findings in some A2BX4 compounds.

</DOC>
<DOC>
<DOCNO> 119200 </DOCNO>
Strong Balmer lines in old stellar populations: No need for young ages


  Comparing models of Simple Stellar Populations (SSP) with observed line
strengths generally provides a tool to break the age-metallicity degeneracy in
elliptical galaxies. Due to the wide range of Balmer line strengths observed,
ellipticals have been interpreted to exhibit an appreciable scatter in age. In
this paper, we analyze Composite Stellar Population models with a simple mix of
an old metal-rich and an old metal-poor component. We show that these models
simultaneously produce strong Balmer lines and strong metallic lines without
invoking a young population. The key to this result is that our models are
based on SSPs that better match the steep increase of Hbeta in metal-poor
globular clusters than models in the literature. Hence, the scatter of Hbeta
observed in cluster and luminous field elliptical galaxies can be explained by
a spread in the metallicity of old stellar populations. We check our model with
respect to the so-called G-dwarf problem in ellipticals. For a galaxy subsample
covering a large range in UV-V colors we demonstrate that the addition of an
old metal-poor subcomponent does not invalidate other observational constraints
like colors and the flux in the mid-UV.

</DOC>
<DOC>
<DOCNO> 85093 </DOCNO>
No-interaction theorem without Hamiltonian and Lagrangian formalism:


  In a previous paper (G.Yoneda, Proc.R.Soc.London, A445,(1994),221), we proved
the no-interaction theorem for four particles with the assumption that the
(linear and angular) momentum on space-like planes is invariant. In this paper,
we assume that the momentum on null cones is invariant and prove that there is
no interaction for four particles.

</DOC>
<DOC>
<DOCNO> 70379 </DOCNO>
Couplings of a Light Dilaton and Violations of the Equivalence Principle


  Experimental discovery of the dilaton would provide strong evidence for
string theory. A light dilaton could show up in current tests of the inverse
square law for gravity at sub-millimeter distances. In the large extra
dimension scenario, Kaluza-Klein excitations of the dilaton can also contribute
to the cooling of supernovae. In order to quantify these effects we compute the
couplings of a low energy dilaton to matter. These predominantly arise from the
fundamental dilaton coupling to the gluon field strength, which receives a
sizable enhancement from QCD scaling. We show that detection of the dilaton
will give a direct measurement of the QCD coupling constant at the string
scale. Particular attention is paid to the size of equivalence principle
violating dilaton couplings.

</DOC>
<DOC>
<DOCNO> 12863 </DOCNO>
Statistical Analysis of Native Contact Formation in the Folding of


  The time evolution of the formation probability of native bonds has been
studied for designed sequences which fold fast into the native conformation.
  From this analysis a clear hierarchy of bonds emerge a) local, fast forming
highly stable native bonds built by some of the most strongly interacting amino
acids of the protein, b) non-local bonds formed late in the folding process, in
coincidence with the folding nucleus, and involving essentially the same
strongly interacting amino acids already participating in the fast bonds, c)
the rest of the native bonds whose behaviour is subordinated, to a large
extent, to that of the local- and non-local native contacts.

</DOC>
<DOC>
<DOCNO> 11600 </DOCNO>
Absence of Replica Symmetry Breaking in a Region of the Phase Diagram of


  We prove that the distribution functions of magnetization and spin glass
order parameter coincide on the Nishimori line in the phase diagram of the $\pm
J$ Ising model in any dimension. This implies absence of replica symmetry
breaking because the distribution function of magnetization consists only of
two delta functions, suggesting the same simple structure for the distribution
of spin glass order parameter. It then follows that the mixed (glassy) phase,
where the ferromagnetic order coexists with complex phase space, should lie, if
any, below the Nishimori line. We also argue that the AT line to mark the onset
of RSB with a continous distribution of the spin glass order parameter, if any
again, would start with an infinite slope from the multicritical point where
paramagnetic, ferromagnetic and spin glass phases merge.

</DOC>
<DOC>
<DOCNO> 12886 </DOCNO>
Invalidation of the Kelvin Force in Ferrofluids


  Direct and unambiguous experimental evidence for the magnetic force density
being of the form $M\nabla B$ in a certain geometry - rather than being the
Kelvin force $M\nabla H$ - is provided for the first time. (M is the
magnetization, H the field, and B the flux density.)

</DOC>
<DOC>
<DOCNO> 40626 </DOCNO>
Electrooptical Measurements of Ultrashort 45 MeV Electron Beam Bunches


  We have measured the temporal duration of 45 MeV picosecond electron beam
bunches using a noninvasive electro-optical (EO) technique. The amplitude of
the EO modulation was found to increase linearly with electron beam charge and
decrease inversely with distance from the electron beam. The risetime of the
temporal signal was limited by our detection system to ~70ps. The EO signal due
to ionization caused by the electrons traversing the EO crystal was also
observed. It has a distinctively long decay time constant and signal polarity
opposite to that due to the field induced by the electron beam. The
electro-optical technique may be ideal for the measurement of bunch length of
femtosecond, relativistic, high energy, charged, particle beams.

</DOC>
<DOC>
<DOCNO> 121259 </DOCNO>
Interpreting the kinematics of the extended gas in distant radiogalaxies


  The nature of the extreme kinematics in the extended gas of distant radio
galaxies (z>0.7) is still an open question. With the advent of the 8-10 m
telescope generation and the development of NIR arrays we are in the position
for the first time to develop a more detailed study by using lines other than
Lya and [OII]3727 depending on redshift. In this paper we review the main
sources of uncertainty in the interpretation of the emission line kinematics:
the presence of several kinematic components, Lya absorption by neutral
gas/dust and the contribution of scattered light to some of the lines. As an
example, several kinematic components can produce apparent, false rotation
curves. We propose methods to solve these uncertainties. We propose to extend
the methods applied to low redshift radio galaxies to investigate the nature of
the kinematics in distant radio galaxies: by means of the spectral
decomposition of the strong optical emission lines (redshifted into the NIR) we
can isolate the different kinematic components and study the emission line
ratios for the individual components. If shocks are responsible for the extreme
kinematics, we should be able to isolate a kinematic component (the shocked
gas) with large FWHM (>900 km/s), low ionization level [OIII]5007/Hb~2-4 and
weak HeII4686/Hb<0.07, together with a narrow component (~few hundred km/s)
with higher ionization level and strong HeII emission (HeII/Hb~0.5)

</DOC>
<DOC>
<DOCNO> 122881 </DOCNO>
X-ray transients in quiescence


  Transient X-ray binaries remain in their quiescent state for a long time
(months to hundred years) and then bright up as the most powerful sources of
the X-ray sky. While it is clear that, when in outbursts, transient binaries
are powered by accretion, the origin of the low luminosity X-ray emission that
has been detected in the quiescent state has different interpretations and
provides the unique opportunity for testing different accretion regimes. In
this paper we concentrate on the various aspects of the accretion physics at
low rates onto compact objects. We describe the observational panorama of
quiescent emission for the three classes of X-ray transients and try to
interpret these data in light of the different regimes accessible at such low
mass inflow rates.

</DOC>
<DOC>
<DOCNO> 123131 </DOCNO>
Scaling of N-body calculations


  We report results of collisional N-body simulations aimed to study the
N-dependance of the dynamical evolution of star clusters. Our clusters consist
of equal-mass stars and are in virial equilibrium. Clusters moving in external
tidal fields and clusters limited by a cut-off radius are simulated. Our main
focus is to study the dependence of the lifetimes of the clusters on the number
of cluster stars and the chosen escape condition.
  We find that star clusters in external tidal fields exhibit a scaling problem
in the sense that their lifetimes do not scale with the relaxation time.
Isolated clusters show a similar problem if stars are removed only after their
distance to the cluster centre exceeds a certain cut-off radius. If stars are
removed immediately after their energy exceeds the energy necessary for escape,
the scaling problem disappears.
  We show that some stars which gain the energy necessary for escape are
scattered to lower energies before they can leave the cluster. Since the
efficiency of this process decreases with increasing particle number, it causes
the lifetimes not to scale with the relaxation time. Analytic formulae are
derived for the scaling of the lifetimes in the different cases.

</DOC>
<DOC>
<DOCNO> 7989 </DOCNO>
On the importance of grain boundaries in high-Tc films: simulation


  The importance of the distribution and ``weakness'' of grain boundary
junctions in the magnetic field dependence of the transport critical current in
HTc films is assessed through simulations. The system is studied with the
applied field either parallel or perpendicular to the c axis of the sample. For
realistic sample parameters, it is demonstrated that the presence of ``high''
misorientation angles between grains depresses the zero - field critical
current density in both orientations, and provokes a transition from
pinning-mediated to Fraunhoffer-like field dependencies of the critical current
density. Our results also suggest that there is a threshold misorientation
angle above which the critical current density remains constant.

</DOC>
<DOC>
<DOCNO> 69412 </DOCNO>
CP Violation in Top Physics


  CP violation in top physics is reviewed. The Standard Model has negligible
effects, consequently CP violation searches involving the top quark may
constitute the best way to look for physics beyond the Standard Model.
Non-standard sources of CP violation due to an extended Higgs sector with and
without natural flavor conservation and supersymmetric theories are discussed.
Experimental feasibility of detecting CP violation effects in top quark
production and decays in high energy e+ e-, gamma-gamma, mu+ mu-, pp and p-bar
p colliders are surveyed. Searches for the electric, electro-weak and the
chromo-electric dipole moments of the top quark in e+ e- -> t-bar t and in p p
-> t-bar t X are descibed. In addition, other mechanisms that appear promising
for experiments, e.g., tree-level CP violation in e+ e- -> t-bar t h, t-bar t
Z, t-bar t nu_e-bar nu_e and in the top decay t -> b tau nu_tau and CP
violation driven by s-channel Higgs exchanges in p p, gamma gamma, mu+ mu- ->
t-bar t etc., are also discussed.

</DOC>
<DOC>
<DOCNO> 150617 </DOCNO>
A review of the D1/D5 system and five dimensional black hole from


  We review some aspects of the D1/D5 system of type IIB string theory and the
associated five dimensional black hole. We include a pedagogical discussion of
the construction of relevant classical solutions in supergravity. We discuss
the gauge theory and the conformal field theory relevant to D-brane description
of these systems. In order to discuss Hawking radiation we are automatically
led to a discussion of near-horizon geometries and their relation to gauge
theories and conformal field theories. We show how inputs from AdS/CFT
correspondence resolve some earlier puzzles regarding Hawking radiation.
Besides the D1/D5 system, we include a brief discussion of some
nonsupersymmetric systems which show unexpected agreement between supergravity
and perturbative brane/string computations. We also comment briefly on possible
implications of the AdS/CFT relation for the correspondence principle and for
the principle of black hole complementarity.

</DOC>
<DOC>
<DOCNO> 10123 </DOCNO>
The Role of Spin-Dependent Interface Scattering in Generating


  We present a calculation of current-induced torques in metallic magnetic
multilayers derived from the spin-dependent transmission and reflection
properties of the magnetic layers. A scattering formalism is employed to
calculate the torques in a magnetic-nonmagnetic-magnetic trilayer, for currents
perpendicular to the layers, in both the ballistic and diffusive regimes.

</DOC>
<DOC>
<DOCNO> 120549 </DOCNO>
Pair-Instability Supernovae, Gravity Waves, and Gamma-Ray Transients


  Growing theoretical evidence suggests that the first generation of stars may
have been quite massive (~100-300 solar masses). If they retain their high mass
until death, such stars will, after about 3Myr, make pair-instability
supernovae. We consider the complete evolution of two zero-metallicity stars of
250 and 300 solar masses. Explosive oxygen and silicon burning cause the 130
solar mass helium core to explode, but explosive burning is unable to drive an
explosion in the 300 solar mass star and it collapses to a black hole. For this
star, the calculated angular momentum in the presupernova model is sufficient
to delay black hole formation and the star initially forms a 50 solar mass,
1000km core within which neutrinos are trapped. Although the star does not
become dynamically unstable, the calculated growth time of secular rotational
instabilities is shorter than the black hole formation time, and such
instabilities may develop. We estimate the energy and amplitude of the
gravitational waves emitted during this collapse. After the black hole forms,
accretion continues through a disk. Although the disk is far too large and cool
to transport energy efficiently to the rotational axis by neutrino
annihilation, it has ample potential energy to produce a 1e54erg jet driven by
magnetic fields. The interaction of this jet with surrounding circumstellar gas
may produce an energetic gamma-ray transient, but given the redshift and time
scale, this is probably not a model for typical gamma-ray bursts.

</DOC>
<DOC>
<DOCNO> 11943 </DOCNO>
Life in the Stockmarket - a Realistic Model for Trading


  We propose a frustrated and disordered many-body model of a stockmarket in
which independent adaptive traders can trade a stock subject to the economic
law of supply and demand. We show that the typical scaling properties and the
correlated volatility arise as a consequence of the collective behavior of
agents: With their interaction they determine a price which in turn affects
their future way of investing. We introduce only one type of investors, since
they all share the same hope: They simply want to maximize the profit
minimizing the risk. The best utilization of resources occurs at a critical
point characterized by the transition between the excess-demand and the
excess-supply phases.

</DOC>
<DOC>
<DOCNO> 121245 </DOCNO>
Starburst or Seyfert? Adding a radio and far-infrared perspective to the


  It was once common to regard Seyfert and starburst galaxies as completely
different types of object, but there is growing recognition that these
classifications refer to the extremes of a continuous spectrum of galaxy types.
In a previous study we investigated a sample of galaxies with ambiguous optical
emission-line ratios and concluded from near-infrared spectroscopic
observations that the sample consisted of composite galaxies, containing both a
starburst and an active galactic nucleus (AGN). We now extend our study using
radio synthesis and long-baseline interferometer observations made with the
Australia Telescope, together with far-infrared IRAS observations, to discuss
the relative contribution of starburst and AGN components to the overall
luminosity of the composite galaxies. We find that only a small fraction of the
radio emission (<10%) can be attributed to an AGN, and that the majority of the
far-infrared emission (>90%) is probably due to the starburst component. We
also show that an AGN contribution to the optical emission of as little as 10%
is sufficient to account for the ambiguous line-ratio diagnostics.

</DOC>
<DOC>
<DOCNO> 152160 </DOCNO>
On the correspondence between D-branes and stationary supergravity


  In this talk, I review how four dimensional stationary supergravity solutions
that are more general than spherically symmetric black holes emerge naturally
in the low energy description of BPS states in type II Calabi-Yau
compactifications. An explicit construction of multicenter solutions using
single center attractor flows as building blocks is presented, and some
interesting properties of these solutions are examined. We end with a brief
remark on non-BPS configurations.

</DOC>
<DOC>
<DOCNO> 85307 </DOCNO>
Bogoliubov Coefficients of 2D Charged Black Holes


  We exactly calculate the thermal distribution and temperature of Hawking
radiation for a two-dimensional charged dilatonic black hole after it has
settled down to an "equilibrium" state. The calculation is carried out using
the Bogoliubov coefficients. The background of the process is furnished by a
preexisting black hole and not by collapsing matter as considered by Giddings
and Nelson for the case of a Schwarzschild black hole. Furthermore, the
vanishing of the temperature and/or the Hawking radiation in the extremal case
is obtained as a regular limit of the general case.

</DOC>
<DOC>
<DOCNO> 101457 </DOCNO>
A geometric interpretation and a new proof of a relation by Cornalba and


  In the 80's M. Cornalba and J. Harris discovered a relation among the Hodge
class and the boundary classes in the Picard group with rational coefficients
of the moduli space of stable, hyperelliptic curves. They proved the relation
by computing degrees of the classes involved for suitable one-parameter
families. In the present article we show that their relation can be obtained as
the class of an appropriate, geometrically meaningful empty set, thus
conforming with C. Faber's general philosophy to finding relations among
tautological classes in the Chow ring of the moduli space of curves. The empty
set we consider is the closure of the locus of smooth, hyperelliptic curves
having a special ramification point.

</DOC>
<DOC>
<DOCNO> 12061 </DOCNO>
Sensitivity of a micromechanical displacement detector based on the


  We investigate the tunneling shot noise limits on the sensitivity of a
micromechanical displacement detector based on a metal junction,
radio-frequency single-electron transistor (rf-SET). In contrast with the
charge sensitivity of the rf-SET electrometer, the displacement sensitivity
improves with increasing gate voltage bias and, with a suitably optimized
rf-SET, displacement sensitivities of $10^{-6} {\rm\AA}/\sqrt{\rm Hz}$ may be
possible.

</DOC>
<DOC>
<DOCNO> 8384 </DOCNO>
A Mean Atom Trajectory Model for Monatomic Liquids


  A recent description of the motion of atoms in a classical monatomic system
in liquid and supercooled liquid states divides the motion into two parts:
oscillations within a given many-particle potential valley, and transit motion
which carries the system from one many-particle valley to another. Building on
this picture, we construct a model for the trajectory of an average atom in the
system. The trajectory consists of oscillations at the normal-mode distribution
of frequencies, representing motion within a fluctuating single-particle well,
interspersed with position- and velocity-conserving transits to similar
adjacent wells. For the supercooled liquid in nondiffusing states, the model
gives velocity and displacement autocorrelation functions which exactly match
those found in the many-particle harmonic approximation, and which are known to
agree almost precisely with molecular dynamics (MD) simulations of liquid Na.
At higher temperatures, by allowing transits to proceed at a
temperature-dependent rate, the model gives velocity autocorrelation functions
which are also in remarkably good agreement with MD simulations of Na at up to
three times its melting temperature. Two independent processes in the model
relax velocity autocorrelations: (a) dephasing due to the presence of many
frequency components, which operates at all temperatures but which produces
zero diffusion, and (b) the transit process, which increases with increasing
temperature and which produces diffusion.

</DOC>
<DOC>
<DOCNO> 178531 </DOCNO>
Studying the $\omega$ properties in pA collisions via the


  Within transport calculations we study the production and decay of
$\omega$-mesons in $pA$ reactions at COSY energies including elastic and
inelastic ${\omega}N$ rescattering, the $\omega{\to}\pi^0\gamma$ Dalitz decay
as well as $\pi^0 N$ rescattering. The resulting invariant $\pi^0 \gamma$ mass
distributions indicate that in-medium modifications of the $\omega$-meson may
be observed experimentally.

</DOC>
<DOC>
<DOCNO> 116901 </DOCNO>
Studies of Coupled Cavity Linac (CCL) Accelerating Structures with 3-D


  The cw CCL being designed for the Accelerator Production of Tritium (APT)
project accelerates protons from 96MeV to 211MeV. It consists of 99 segments
each containing up to seven accelerating cavities. Segments are coupled by
intersegment coupling cavities and grouped into supermodules. The design method
needs to address not only basic cavity sizing for a given coupling and pi/2
mode frequency, but also the effects of high power densities on the cavity
frequency, mechanical stresses, and the structure's stop band during operation.
On the APT project, 3-D RF (Ansoft Corp.'s HFSS) and coupled RF/structural
(Ansys Inc.'s ANSYS) codes are being used to develop tools to address the above
issues and guide cooling channel design. The code's predictions are being
checked against available low power Aluminum models. Stop band behavior under
power will be checked once the tools are extended to CCDTL structures that have
been tested at high power. A summary of calculations made to date and agreement
with measured results will be presented.

</DOC>
<DOC>
<DOCNO> 10322 </DOCNO>
Solid like friction of a polymer chain


  We propose a simple friction model for isolated polymer chains on a solid
substrate. The chains are pulled at constant velocity by one end, the other end
can be trapped on the solid substrate on localised sites. We focus on the
energy dissipation due to the traps. This simple model leads to non trivial
friction laws, depending on the velocity and the distance between traps. Some
refinements of the model such as the effect of thermal fluctuation are also
reported.

</DOC>
<DOC>
<DOCNO> 9611 </DOCNO>
Boundary induced phase transitions in driven lattice gases with


  We study boundary induced phase transitions in a driven lattice gas
exhibiting metastability. The phase diagram for open systems, parameterized by
the input and output rates, consists of two regions corresponding to the free
flow and jammed phase. Both have been entirely characterized. The microscopic
states in the high density phase are shown to have an interesting striped
structure, which survives in the thermodynamic limit.

</DOC>
<DOC>
<DOCNO> 118082 </DOCNO>
Prompt and afterglow emission from the X-ray rich GRB981226 observed


  We discuss observations of the prompt X and gamma-ray emission and X-ray
afterglow from GRB981226. This event has the weakest gamma-ray peak flux
detected with the Gamma-Ray Burst Monitor. It shows an isolated X-ray precursor
and the highest X-ray to gamma-ray fluence ratio measured thus far with the
Wide Field Cameras. The event was followed up with the Narrow Field
Instruments, and the X-ray afterglow was detected up to 10 keV. The afterglow
flux is observed to rise from a level below the sensitivity of the MECS/LECS
telescopes up to a peak flux of (5 +/-1) * 10^(-13) erg cm-2 s-1, in the 2-10
keV energy band. This rise is followed by a decline according to a power law
with index of 1.31 (+0.44,-0.39). We discuss these results in the light of the
current GRB models.

</DOC>
<DOC>
<DOCNO> 102050 </DOCNO>
On the Hilbert transform and lacunary directions in the plane


  Let $H_k$ be the one dimensional Hilbert transform computed in the direction
$(1,2^k)$ in the plane. We show that the maximal operator $\sup_k |H_kf|$ maps
$L^p$ of the plane into itself for $1<p<\infty$.
  The same result with the Hilbert transform replaced by the one dimensional
maximal function was proved by Nagel, Stein and Wainger in 1978.

</DOC>
<DOC>
<DOCNO> 71919 </DOCNO>
Exploring Neutrino Oscillations with Superbeams


  We consider the medium- and long-baseline oscillation physics capabilities of
intense muon-neutrino and muon-antineutrino beams produced using future
upgraded megawatt-scale high-energy proton beams. In particular we consider the
potential of these conventional neutrino ``superbeams'' for observing
\nu_\mu\to\nu_e oscillations, determining the hierarchy of neutrino mass
eigenstates, and measuring CP-violation in the lepton sector. The physics
capabilities of superbeams are explored as a function of the beam energy,
baseline, and the detector parameters. The trade-offs between very large
detectors with poor background rejection and smaller detectors with excellent
background rejection are illustrated. We find that it may be possible to
observe \nu_\mu\to\nu_e oscillations with a superbeam provided that the
amplitude parameter \sin^2 2\theta_{13} is larger than a few \times 10^{-3}. If
\sin^2 2\theta_{13} is of order 10^{-2} or larger, then the neutrino mass
hierarchy can be determined in long-baseline experiments, and if in addition
the large mixing angle MSW solution describes the solar neutrino deficit then
there is a small region of parameter space within which maximal CP-violation in
the lepton sector would be observable in a low-energy medium-baseline
experiment. We explicitly consider massive water Cherenkov and liquid argon
detectors at superbeams with neutrino energies ranging from 1 GeV to 15 GeV,
and baselines from 295 km to 9300 km. Finally, we compare the oscillation
physics prospects at superbeams with the corresponding prospects at neutrino
factories. The sensitivity at a neutrino factory to CP violation and the
neutrino mass hierarchy extends to values of the amplitude parameter \sin^2
2\theta_{13} that are one to two orders of magnitude lower than at a superbeam.

</DOC>
<DOC>
<DOCNO> 9292 </DOCNO>
Thermodynamic limit of the Six-Vertex Model with Domain Wall Boundary


  We address the question of the dependence of the bulk free energy on boundary
conditions for the six vertex model. Here we compare the bulk free energy for
periodic and domain wall boundary conditions. Using a determinant
representation for the partition function with domain wall boundary conditions,
we derive Toda differential equations and solve them asymptotically in order to
extract the bulk free energy. We find that it is different and bears no simple
relation with the free energy for periodic boundary conditions. The six vertex
model with domain wall boundary conditions is closely related to algebraic
combinatorics (alternating sign matrices). This implies new results for the
weighted counting for large size alternating sign matrices. Finally we comment
on the interpretation of our results, in particular in connection with domino
tilings (dimers on a square lattice).

</DOC>
<DOC>
<DOCNO> 150591 </DOCNO>
A New Class of Supersymmetric Orientifolds with D-Branes at Angles


  We describe a new class of supersymmetric orientifolds which combine the
world-sheet parity transformation with a complex conjugation in the compact
directions. As an example, we investigate in detail the orientifold of the Z_3
toroidal orbifold in six and four dimensions. We demonstrate how the solution
to the tadpole cancellation conditions, the resulting gauge groups and the
massless spectra depend on the choice of the complex structures on the tori,
giving rise to a variety of inequivalent models. We also summarize the results
for the orientifolds of the Z_4, Z_6 and Z_6' orbifolds in four and six
dimensions.

</DOC>
<DOC>
<DOCNO> 150603 </DOCNO>
Vector supersymmetry in topological field theories


  We present a simple derivation of vector supersymmetry transformations for
topological field theories of Schwarz- and Witten-type. Our method is similar
to the derivation of BRST-transformations from the so-called horizontality
conditions or Russian formulae. We show that this procedure reproduces in a
concise way the known vector supersymmetry transformations of various
topological models and we use it to obtain some new transformations of this
type for 4d topological YM-theories in different gauges.

</DOC>
<DOC>
<DOCNO> 118706 </DOCNO>
Deriving the Nonlinear Cosmological Power Spectrum and Bispectrum from


  We present an analytic model for the fully nonlinear power spectrum P and
bispectrum Q of the cosmological mass density field. The model is based on
physical properties of dark matter halos, with the three main model inputs
being analytic halo density profiles, halo mass functions, and halo-halo
spatial correlations, each of which has been well studied in the literature. We
demonstrate that this new model can reproduce the power spectrum and bispectrum
computed from cosmological simulations of both an n=-2 scale-free model and a
low-density cold dark matter model. To enhance the dynamic range of these large
simulations, we use the synthetic halo replacement technique of Ma & Fry
(2000a), where the original halos with numerically softened cores are replaced
by synthetic halos of realistic density profiles. At high wavenumbers, our
model predicts a slope for the nonlinear power spectrum different from the
often-used fitting formulas in the literature based on the stable clustering
assumption. Our model also predicts a three-point amplitude Q that is scale
dependent, in contrast to the popular hierarchical clustering assumption. This
model provides a rapid way to compute the mass power spectrum and bispectrum
over all length scales where the input halo properties are valid. It also
provides a physical interpretation of the clustering properties of matter in
the universe.

</DOC>
<DOC>
<DOCNO> 101614 </DOCNO>
Projective varieties invariant by one-dimensional foliations


  This work concerns the problem of relating characteristic numbers of
one-dimensional holomorphic foliations of P^n to those of algebraic varieties
invariant by them. More precisely: if M is a connected complex manifold, a
one-dimensional holomorphic foliation F of M is a morphism \Phi:L -> TM where
L is a holomorphic line bundle on M. The singular set of F is the analytic
subvariety sing(F) = {p : \Phi(p)=0} and the leaves of F are the leaves of the
nonsingular foliation induced by F on M-sing(F). If M is P^n then, since line
bundles over P^n are classified by the Chern class c_1(L) in H^2(P^n,Z) = Z,
one-dimensional holomorphic foliations F of P^n are given by morphisms
Phi:O(1-d) -> TP^n with d >= 0, d in Z, which we call the degree of F. We will
use the notation F^d for such a foliation. Suppose now i:V -> P^n is an
irreducible algebraic variety invariant by F^d in such a way that the
pull-back i^*(F^d) of F^d to V has a finite set of points as the singular set.
The problem we address is the relation between d and the degree of V.

</DOC>
<DOC>
<DOCNO> 8007 </DOCNO>
Numerical Study on Aging Dynamics in Ising Spin-Glass Models:


  By means of Monte Carlo simulations on the three-dimensional Ising spin-glass
model, we have studied aging phenomena with various temperature($T$)-change
protocols. Particularly, a $T$-shift protocol, in which a system is first
quenched to and aged for a period $t_{\rm w1}$ at a temperature $T_1$, and
subsequently aged at a new temperature $T_2$ is closely investigated. Most
importantly, the mean size of domains, which is extracted from the
replica-overlap function, was found to grow monotonically without any
appreciable decrease by the $T$-change. We also found the relaxation of energy
density and spin auto-correlation function during the $T$-shift process can be
explained within the following picture: the dynamics finally crossovers to an
isothermal aging of $T_2$ at around $t_2 \simeq t_{\rm w1}^{\rm (eff)}$ after
the $T$-change, where $t_{\rm w1}^{\rm (eff)}$ is an effective waiting time
related with $t_{\rm w1}$, but in the transient regime $t_2 \lt t_{\rm w1}^{\rm
(eff)}$, adjustment of the population of thermally active droplets from that at
$T_1$ to $T_2$ takes place very slowly. Implications of the results on aging
phenomena in other $T$-change protocols such as $T$-cycling and continuous
$T$-change with an intermittent stop observed by simulations as well as
experiments are discussed.

</DOC>
<DOC>
<DOCNO> 69189 </DOCNO>
Neutrino oscillations in high energy cosmic neutrino flux


  I discuss the effects of neutrino oscillations on high energy cosmic
neutrinos which come from cosmologically distant astrophysical sources. I
incorporate all the up-to-date constraints from the solar, atmospheric,
reactor, accelerator data and give the possible pattern for the ratio of the
high energy cosmic neutrinos in the cases of three and four neutrino schemes.

</DOC>
<DOC>
<DOCNO> 99726 </DOCNO>
Monodromy of elliptic surfaces


  We study monodromy groups of elliptic fibrations over the projective line.

</DOC>
<DOC>
<DOCNO> 122744 </DOCNO>
The Gravitational Lens Candidate FBQ 1633+3134


  We present our ground-based optical imaging, spectral analysis, and high
resolution radio mapping of the gravitational lens candidate FBQ 1633+3134.
This z=1.52, B=17.7 quasar appears double on CCD images with an image
separation of 0.66 arcseconds and a flux ratio of ~3:1 across BVRI filters. A
single 0.27 mJy radio source is detected at 8.46 GHz, coincident to within an
arcsecond of both optical components, but no companion at radio wavelengths is
detected down to a flux level of 0.1 mJy (3 sigma). Spectral observations
reveal a rich metal-line absorption system consisting of a strong Mg II doublet
and associated Fe I and Fe II absorption features, all at an intervening
redshift of z=0.684, suggestive of a lensing galaxy. Point spread function
subtraction however shows no obvious signs of a third object between the two
quasar images, and places a detection limit of I > 23.0 if such an object
exists. Although the possibility that FBQ 1633+3134 is a binary quasar cannot
be ruled out, the evidence is consistent with it being a single quasar lensed
by a faint, metal-rich galaxy.

</DOC>
<DOC>
<DOCNO> 7908 </DOCNO>
Decoherence in Bose-Einstein Condensates: towards Bigger and Better


  We consider a quantum superposition of Bose-Einstein condensates in two
immiscible internal states. A decoherence rate for the resulting Schroedinger
cat is calculated and shown to be a significant threat to this macroscopic
quantum superposition of BEC's. An experimental scenario is outlined where the
decoherence rate due to the thermal cloud is dramatically reduced thanks to
trap engineering and "symmetrization" of the environment which allow for the
Schroedinger cat to be an approximate pointer states.

</DOC>
<DOC>
<DOCNO> 121281 </DOCNO>
HI Imaging of the Large Magellanic Cloud


  We present results from the combined Australia Telescope Compact Array (ATCA)
aperture synthesis mosaic survey of HI emission in the Large Magellanic Cloud
with 64m Parkes single dish telescope observations.

</DOC>
<DOC>
<DOCNO> 151531 </DOCNO>
Non-BPS D-branes and enhanced symmetry in an asymmetric orbifold


  In this paper properties of D branes in a nine dimensional asymmetric
orbifold are discussed, using a $(-1)^{F_L}\sigma_{1/2}$ projection, where
$F_L$ is the leftmoving space-time fermion number and $\sigma_{1/2}$ is a
freely acting shift of order two. There are two types of non BPS D branes,
which are stable at $R>2$ and $R<2$ respectively. At R=2 there is a
perturbative enhancement of gauge symmetry and the two types of branes are
related by a global bulk symmetry transformation. At this point in the moduli
space the associated boundary states are constructed using a free fermion
representation of the theory. Some aspects of the enhancement of gauge symmetry
in the S-dual type $\tilde I$ theory are discussed.

</DOC>
<DOC>
<DOCNO> 10154 </DOCNO>
Coherent phenomena in mesoscopic systems


  A mesoscopic system of cylindrical geometry made of a metal or a
semiconductor is shown to exhibit features of a quantum coherent state. It is
shown that magnetostatic interaction can play an important role in mesoscopic
systems leading to an ordered ground state. The temperature $T^{*}$ below the
system exhibits long-range order is determined. The self-consistent mean field
approximation of the magnetostatic interaction is performed giving the
effective Hamiltonian from which the self-sustaining currents can be obtained.
  The relation of quantum coherent state in mesoscopic cylinders to other
coherent systems like superconductors is discussed.

</DOC>
<DOC>
<DOCNO> 40598 </DOCNO>
Recent Results on Charm and Hyperon Physics from SELEX


  The SELEX experiment (Fermilab E781) is a 3-stage magnetic spectrometer for
the study of charm hadroproduction at large x_F using 600GeV/c Sigma-, pi-, and
p beams. New precise measurements of the Lambda_c, D0, and Ds lifetimes are
presented. Results on Lambda_c and D_s production for x_F>0.2 are reported as
well. The spectrometer was also used for hyperon physics, where we will show
measurements of the Sigma- charge radius, the polarization of inclusive
produced Lambda's, and the polarization of beam Sigma+.

</DOC>
<DOC>
<DOCNO> 117182 </DOCNO>
Modeling of an Inductive Adder Kicker Pulser for Darht-II


  An all solid-state kicker pulser for a high current induction accelerator
(the Dual-Axis Radiographic Hydrodynamic Test facility DARHT-2) has been
designed and fabricated. This kicker pulser uses multiple solid state
modulators stacked in an inductive-adder configuration. Each modulator is
comprised of multiple metal-oxide-semiconductor field-effect transistors
(MOSFETs) which quickly switch the energy storage capacitors across a magnetic
induction core. Metglas is used as the core material to minimize loss. Voltage
from each modulator is inductively added by a voltage summing stalk and
delivered to a 50 ohm output cable. A lumped element circuit model of the
inductive adder has been developed to optimize the performance of the pulser.
Results for several stalk geometries will be compared with experimental data.

</DOC>
<DOC>
<DOCNO> 152507 </DOCNO>
Finiteness of PST self-dual models


  The Pasti-Sorokin-Tonin model for describing chiral forms is considered at
the quantum level. We study the ultraviolet and infrared behaviour of the model
in two, four and six dimensions in the framework of algebraic renormalization.
The absence of anomalies, as well as the finiteness, up to non-physical
renormalizations, are shown in all dimensions analyzed.

</DOC>
<DOC>
<DOCNO> 80916 </DOCNO>
$K \to \pi \pi$ Decays with Domain Wall Fermions: Towards Physical


  We are using domain wall fermions to study $K \to \pi \pi$ matrix elements by
measuring $K \to \pi$ and $K \to 0$ matrix elements on the lattice and
employing chiral perturbation theory to relate these to the desired physical
result. The residual chiral symmetry breaking of domain wall fermions with a
finite extent in the fifth dimension impacts these measurements. Using the
Ward-Takahashi identities, we investigate residual chiral symmetry breaking
effects for divergent quantities and study pathologies of the quenched
approximation for small quark mass. We then discuss the $\Delta S = 1$ operator
$O_2$, where chiral symmetry is vital for the subtraction of unphysical
effects.

</DOC>
<DOC>
<DOCNO> 71476 </DOCNO>
Spin effects in diffractive hadron photoproduction


  We study spin asymmetries in diffractive $Q \bar Q$ and vector meson
production which are sensitive to the spin-dependent part of the
two-gluon-nucleon coupling. It is found that the $A_{ll}$ and $A_{lT}$
asymmetry in diffractive reactions can be used to study polarized gluon
distributions of the proton.

</DOC>
<DOC>
<DOCNO> 71346 </DOCNO>
A study of semileptonic B decays


  Perturbative and nonperturbative QCD corrections to semileptonic B decay
rates are calculated and given in analytical and numerical forms. We present
the analytic expression for the double distribution in hadronic mass and
electron energy in B to X(u) e nu_e decays through one loop order of QCD. We
then study the leading twist corrections to that quantity within the formalism
of HQET and employ it in a proposed method of measuring V_ub with an accuracy
of 10%. Our other point of interest is the polarisation of the tau lepton in B
to X(c) tau nu_tau processes. Analytic formulae are given for the one-loop QCD
correction to the longitudinal polarisation. The resulting moments of
distributions are discussed, incorporating the HQET corrections found by Falk
et al. The polarisation receives only a very small perturbative correction. It
can be used in extracting the quark masses. Experimental considerations led us
to the calculation of corrections to the polarisation of tau with respect to
the momentum of the virtual $W$ boson. Analytical results for the O(1/m_b^2)
terms have been combined with numerically evaluated perturbative contributions
to give the corrected polarisation.

</DOC>
<DOC>
<DOCNO> 72185 </DOCNO>
Generating Feynman Diagrams and Amplitudes with FeynArts 3


  This paper describes the Mathematica package FeynArts used for the generation
and visualization of Feynman diagrams and amplitudes. The main features of
version 3 are: generation of diagrams at three levels, user-definable model
files, support for supersymmetric models, and publication-quality Feynman
diagrams in PostScript or LaTeX.

</DOC>
<DOC>
<DOCNO> 120196 </DOCNO>
UV Background-Induced Bifurcation of the Galactic Morphology


  Based upon a novel paradigm of the galaxy formation under UV background, the
evolutionary bifurcation of pregalactic clouds is confronted with observations
on elliptical and spiral galaxies. The theory predicts that the dichotomy
between the dissipational and dissipationless galaxy formation stems from the
degree of self-shielding from the UV background radiation. This is demonstrated
on a bifurcation diagram of collapse epochs versus masses of pregalactic
clouds. Using the observed properties, the collapse epochs are assessed for
each type of galaxies with attentive mass estimation. By the direct comparison
of the theory with the observations, it turns out that the theoretical
bifurcation branch successfully discriminates between elliptical and spiral
galaxies. This suggests that the UV background radiation could play a profound
role for the differentiation of the galactic morphology into the Hubble
sequence.

</DOC>
<DOC>
<DOCNO> 122702 </DOCNO>
Broadband X-ray Spectroscopy of GRS 1915+105


  We analyzed RXTE data of GRS 1915+105 of X-ray low states between 1996 and
1998. The X-ray spectrum is dominated by the power law component. We found (i)
that the power law is pivoting at 10-30 keV, (ii) that the power law slope
correlates with radio flux, (iii) three different groups of 3-10 keV residuals,
(iv) that one of these residual groups correlates with the power law slope.

</DOC>
<DOC>
<DOCNO> 84462 </DOCNO>
No Ghost State in the Brane World


  We discuss the role of the trace part of metric fluctuations $h_{MN}$ in the
Randall-Sundrum scenario of gravity. Without the matter, this field
($h=\eta^{MN}h_{MN}$) is a gauge-dependent term, and thus it can be gauged
away. But, including the uniform source $\tilde{T}_{MN}$, this field satisfies
the linearized equation $\Box_4 h =16\pi G_5 T^{\mu}_{\mu}$. This may
correspond to the scalar $\xi^5$ in the bending of the brane due to the
localized source. Considering the case of longitudinal perturbations ($h_{5\mu}
=h_{55}=0$), one finds the source relation
$\tilde{T}^{\mu}_{\mu}=2\tilde{T}_{55}$, which leads to the ghost states in the
massive modes. In addition, if one requires $T_{44}=2(T_{22}+T_{33})$, it is
found that in the limit of $m^2_h \to 0$ we have the massless spin-2
propagation without the ghost state. This exactly corresponds to the same
situation as in the intermediate scales of Gregory-Rubakov-Sibiryakov (GRS)
model.

</DOC>
<DOC>
<DOCNO> 68566 </DOCNO>
Phenomenological Survey of a Minimal Superstring Standard Model


  We discuss a heterotic-string solution in which the observable sector
effective field theory just below the string scale reduces to that of the MSSM,
with the standard observable gauge group being just SU(3)_C x SU(2)_L x U(1)_Y
and the SU(3)_C x SU(2)_L x U(1)_Y-charged spectrum of the observable sector
consisting solely of the MSSM spectrum. Associated with this model is a set of
distinct flat directions of vacuum expectation values (VEVs) of fields that all
produce solely the MSSM spectrum. Some of these directions only involve VEVs of
non-Abelian singlet fields while others also contain VEVs of non-Abelian
charged fields.

</DOC>
<DOC>
<DOCNO> 69596 </DOCNO>
Radial Excitations of low-lying Baryons and the Structure of the Z^+


  Within the collective quantization scheme for chiral solitons we discuss
states in higher dimensional representations of flavor SU(3) and their relation
to radially excited states in the octet. We also consider states which do not
have counterparts of the same quantum numbers in the octet or decuplet and
cannot be built from three quarks. We focus on the Z^+ penta-quark, presumably
the lightest such state, by estimating its mass and decay width.

</DOC>
<DOC>
<DOCNO> 121167 </DOCNO>
Discovery of nearly coherent oscillations with a frequency of ~567 Hz


  We report the discovery of nearly coherent oscillations with a frequency of
567 Hz during type-I X-ray bursts from the X-ray transient and eclipsing binary
X 1658-298. If these oscillations are directly related to the neutron star
rotation then the spin period of the neutron star in X 1658-298 is 1.8 ms. The
oscillations can be present during the rise or decay phase of the bursts.
Oscillations during the decay phase of the bursts show an increase in the
frequency of 0.5 to 1 Hz. However, in one particular burst the oscillations
reappear at the end of the decay phase at about 571.5 Hz. This represents an
increase in oscillation frequency of about 5 Hz which is the largest frequency
change seen so far in a burst oscillation. It is unclear if such a large change
can be accommodated by present models used to explain the frequency evolution
of the oscillations. The oscillations at 571.5 Hz are unusually soft compared
to the oscillations found at 567 Hz. We also observed several bursts during
which the oscillations are detected at much lower significance or not at all.
Most of these bursts happen during periods of X-ray dipping behavior,
suggesting that the X-ray dipping might decrease the amplitude of the
oscillations (although several complications exist with this simple picture).
We discuss our discovery in the framework of the neutron star spin
interpretation.

</DOC>
<DOC>
<DOCNO> 67733 </DOCNO>
Color, Spin, and Flavor-Dependent Forces in Quantum Chromodynamics


  A simple generalization of the Breit Interaction explains many qualitative
features of the spectrum of hadrons.

</DOC>
<DOC>
<DOCNO> 85002 </DOCNO>
Recovery of the Schwarzschild Metric in Theories with Localized Gravity


  We solve the Einstein equations in the Randall-Sundrum framework with a
static, spherically symmetric matter distribution on the {\it physical brane}
and obtain an approximate expression for the gravitational field outside the
source to second order in the gravitational coupling. This expression when
confined on the {\it physical brane} coincides with the standard form of the
Schwarzschild metric. Therefore, the Randall-Sundrum scenario is consistent
with the Mercury precession test of General Relativity.

</DOC>
<DOC>
<DOCNO> 123016 </DOCNO>
Superfluidity in Neutron Star Matter


  Superfluidity of nuclear matter relevant for neutron star physics is
reviewed.

</DOC>
<DOC>
<DOCNO> 118969 </DOCNO>
Resolving the radio nebula around beta Lyrae


  In this paper we present high spatial resolution radio images of the puzzling
binary system beta Lyrae obtained with MERLIN at 5 GHz. We find a nebula
surrounding the binary with a brightness temperature of 11000+-700K
approximately 40AU across. This definitively confirms the thermal origin of the
radio emission, which is consistent with emission from the wind of the B6-8II
component (mass loss of order of 10^-7 Msun per year), ionized by the radiation
field of the hotter companion. This nebula, surrounding the binary, is the
proof that beta Layrae evolved in a non-conservative way, i. e. not all the
mass lost by the primary is accretted by the secondary, and present
measurements indicate that almost 0.015Msun had been lost from the system since
the onset of the Roche lobe overflow phase. Moreover, the nebula is aligned
with the jet-like structures inferred from recent optical measurements,
indicating a possible connection among them.

</DOC>
<DOC>
<DOCNO> 72025 </DOCNO>
Baryon stopping in high energy collisions in the DPMJET-III model


  A new striking feature of hadron production in nuclear collisions is the
large stopping of the participating nucleons in hadron-nucleus and
nucleus-nucleus collisions. This enhanced baryon stopping can be understood
introducing new diquark breaking mechanisms in multistring models of hadron
production. Here we discuss the implementation of these diagrams into the
DPMJET-III hadronic Monte Carlo model.

</DOC>
<DOC>
<DOCNO> 116720 </DOCNO>
Comment on ``Air bubbles in water: A strongly multiple scattering medium


  We comment on a recent Letter in Phys. Rev. Lett. (M. Kafesaki, R. S. Penciu,
and E. N. Economou, Phys. Rev. Lett. {\bf 84}, 6050 (2000))

</DOC>
<DOC>
<DOCNO> 119146 </DOCNO>
Magnetic Flux Expulsion in the Powerful Superbubble Explosions and the


  The possibility of the magnetic flux expulsion from the Galaxy in the
superbubble (SB) explosions, important for the Alpha-Omega dynamo, is
considered. Special emphasis is put on the investigation of the downsliding of
the matter from the top of the shell formed by the SB explosion which is able
to influence the kinematics of the shell. It is shown that either Galactic
gravity or the development of the Rayleigh-Taylor instabilities in the shell
limit the SB expansion, thus, making impossible magnetic flux expulsion. The
effect of the cosmic rays in the shell on the sliding is considered and it is
shown that it is negligible compared to Galactic gravity. Thus, the question of
possible mechanism of flux expulsion in the Alpha-Omega dynamo remains open.

</DOC>
<DOC>
<DOCNO> 123111 </DOCNO>
Gas fueling and nuclear disk formation in merging between a central


  We numerically investigate dynamical evolution of a merger between a central
massive black hole (MBH) and a gas clump with the mass of $10^6$ $-$ $10^7$
$M_{\odot}$ in the central tens pc of a galactic bulge. We found that strong
tidal gravitational field of the MBH transforms the initial spherical clump
into a moderately thick gaseous disk (or torus) around the MBH. The developed
disk is also found to show rotation, essentially because the tidal field
changes efficiently the orbital angular momentum of the clump into intrinsic
angular momentum of the disk. Furthermore about a few percent of gas mass
(corresponding to a few $10^5$ $M_{\odot}$) in the clump is found to be
transferred to the central sub-parsec region around the MBH within an order of
$10^6$ yr. We thus suggest that successive merging of gas clumps onto a MBH can
not only be associated closely with the formation of nuclear disk around the
MBH but also can provide gas fuel for the MBH.

</DOC>
<DOC>
<DOCNO> 84145 </DOCNO>
A Symplectic Hamiltonian Derivation of Quasilocal Energy-Momentum for GR


  The various roles of boundary terms in the gravitational Lagrangian and
Hamiltonian are explored. A symplectic Hamiltonian-boundary-term approach is
ideally suited for a large class of quasilocal energy-momentum expressions for
general relativity. This approach provides a physical interpretation for many
of the well-known gravitational energy-momentum expressions including all of
the pseudotensors, associating each with unique boundary conditions. From this
perspective we find that the pseudotensors of Einstein and M{\o}ller (which is
closely related to Komar's superpotential) are especially natural, but the
latter has certain shortcomings. Among the infinite possibilities, we found
that there are really only two Hamiltonian-boundary-term quasilocal expressions
which correspond to {\em covariant} boundary conditions; they are respectively
of the Dirichlet or Neumann type. Our Dirichlet expression coincides with the
expression recently obtained by Katz and coworkers using Noether arguments and
a fixed background. A modification of their argument yields our Neumann
expression.

</DOC>
<DOC>
<DOCNO> 68672 </DOCNO>
Renormalization in quantum field theory and the Riemann-Hilbert problem


  We showed in part I (hep-th/9912092) that the Hopf algebra ${\cal H}$ of
Feynman graphs in a given QFT is the algebra of coordinates on a complex
infinite dimensional Lie group $G$ and that the renormalized theory is obtained
from the unrenormalized one by evaluating at $\ve=0$ the holomorphic part
$\gamma_+(\ve)$ of the Riemann-Hilbert decomposition
$\gamma_-(\ve)^{-1}\gamma_+(\ve)$ of the loop $\gamma(\ve)\in G$ provided by
dimensional regularization. We show in this paper that the group $G$ acts
naturally on the complex space $X$ of dimensionless coupling constants of the
theory. More precisely, the formula $g_0=gZ_1Z_3^{-3/2}$ for the effective
coupling constant, when viewed as a formal power series, does define a Hopf
algebra homomorphism between the Hopf algebra of coordinates on the group of
formal diffeomorphisms to the Hopf algebra ${\cal H}$. This allows first of all
to read off directly, without using the group $G$, the bare coupling constant
and the renormalized one from the Riemann-Hilbert decomposition of the
unrenormalized effective coupling constant viewed as a loop of formal
diffeomorphisms. This shows that renormalization is intimately related with the
theory of non-linear complex bundles on the Riemann sphere of the dimensional
regularization parameter $\ve$. It also allows to lift both the renormalization
group and the $\beta$-function as the asymptotic scaling in the group $G$. This
exploits the full power of the Riemann-Hilbert decomposition together with the
invariance of $\gamma_-(\ve)$ under a change of unit of mass. This not only
gives a conceptual proof of the existence of the renormalization group but also
delivers a scattering formula in the group $G$ for the full higher pole
structure of minimal subtracted counterterms in terms of the residue.

</DOC>
<DOC>
<DOCNO> 68488 </DOCNO>
Comment on "A New Dark Matter Candidate: Non-thermal Sterile Neutrinos"


  I point out that the sterile neutrinos suggested as candidates of "cool" Dark
Matter will decay through their mixing with light neutrinos. This leads to an
upper bound of about 200 keV on the mass of the sterile neutrinos, but might
facilitate their detection.

</DOC>
<DOC>
<DOCNO> 68028 </DOCNO>
The Pressure in 2, 2+1 and 3 Flavour QCD


  We calculate the pressure in QCD with two and three light quarks on a lattice
of size 16^3x4 using tree level improved gauge and fermion actions. We argue
that for temperatures T > 2T_c systematic effects due to the finite lattice
cut-off and non-vanishing quark masses are below 15% in this calculation and
give an estimate for the continuum extrapolated pressure in QCD with massless
quarks. We find that the flavour dependence of the pressure is dominated by
that of the Stefan-Boltzmann constant. Furthermore we perform a calculation of
the pressure using 2 light (m_u,d/T=0.4) and one heavier quark (m_s/T = 1). In
this case the pressure is reduced relative to that of three flavour QCD. This
effect is stronger than expected from the mass dependence of an ideal Fermi
gas.

</DOC>
<DOC>
<DOCNO> 8936 </DOCNO>
Creation of Skyrmions in a Spinor Bose-Einstein Condensate


  We propose a scheme for the creation of skyrmions (coreless vortices) in a
Bose-Einstein condensate with hyperfine spin F=1. In this scheme, four
traveling-wave laser beams, with Gaussian or Laguerre-Gaussian transverse
profiles, induce Raman transitions with an anomalous dependence on the laser
polarization, thereby generating the optical potential required for producing
skyrmions.

</DOC>
<DOC>
<DOCNO> 122758 </DOCNO>
An investigation into the prominence of spiral galaxy bulges


  From a diameter-limited sample of 86 `face-on' spiral galaxies, the
bulge-to-disk size and luminosity ratios, and other quantitative measurements
for the prominence of the bulge are derived. The bulge and disk parameters have
been estimated using a seeing convolved Sersic r^(1/n) bulge and a seeing
convolved exponential disk. In general, early-type spiral galaxy bulges have
Sersic values of n>1, and late-type spiral galaxy bulges have values of n<1. In
the B-band, only 8 galaxies have a bulge shape parameter n consistent with the
exponential value of 1, and only 5 galaxies do in the K-band. Application of
the r^(1/n) bulge models results in a larger mean r_e/h ratio for the
early-type spiral galaxies than the late-type spiral galaxies. Although, this
result is shown not to be statistically significant. The mean B/D luminosity
ratio is, however, significantly larger (> 3-sigma) for the early-type spirals
than the late-type spirals. This apparent contradiction with the r_e/h values
can be explained with an iceberg-like scenario, in which the bulges in
late-type spiral galaxies are relatively submerged in their disk. This can be
achieved by varying the relative bulge/disk stellar density while maintaining
the same effective bulge-to-disk size ratio.
 The absolute bulge magnitude - log(n) diagram is used as a diagnostic tool for
comparative studies with dwarf elliptical and ordinary elliptical galaxies. At
least in the B-band, these objects occupy distinctly different regions of this
parameter space. While the dwarf ellipticals appear to be the faint extension
to the brighter elliptical galaxies, the bulges of spiral galaxies are not.

</DOC>
<DOC>
<DOCNO> 118824 </DOCNO>
Pulsational M_V versus [Fe/H] relation(s) for globular cluster RR Lyrae


  We use the results from recent computations of updated non-linear convective
pulsating models to constrain the distance modulus of Galactic globular
clusters through the observed periods of first overtone RRc pulsators. The
resulting relation between the mean absolute magnitude of RR Lyrae stars
<M_V(RR)> and the heavy element content [Fe/H] appears well in the range of
several previous empirical calibrations, but with a non linear dependence on
[Fe/H] so that the slope of the relation increases when moving towards larger
metallicities. On this ground, our results suggest that metal-poor
([Fe/H]<-1.5) and metal-rich ([Fe/H]>-1.5) variables follow two different
linear <M_V(RR)>-[Fe/H] relations. Application to RR Lyrae stars in the
metal-poor globular clusters of the Large Magellanic Cloud provides a LMC
distance modulus of the order of 18.6 mag, thus supporting the "long" distance
scale. The comparison with recent predictions based on updated stellar
evolution theory is shortly presented and discussed.

</DOC>
<DOC>
<DOCNO> 170271 </DOCNO>
Universal trend of the information entropy of a fermion in a mean field


  We calculate the information entropy of single-particle states in
position-space $S_{r}$ and momentum-space $S_{k}$ for a nucleon in a nucleus, a
$\Lambda$ particle in a hypernucleus and an electron in an atomic cluster. It
is seen that $S_{r}$ and $S_{k}$ obey the same approximate functional form as
functions of the number of particles, $S_{r}$ ({\rm or} $S_{k}) = a+bN^{1/3}$
in all of the above many-body systems in position- and momentum- space
separately. The net information content $S_{r}+S_{k}$ is a slowly varying
function of $N$ of the same form as above. The entropy sum $S_{r}+S_{k}$ is
invariant to uniform scaling of coordinates and a characteristic of the
single-particle states of a specific system. The order of single-particle
states according to $S_r +S_k$ is the same as their classification according to
energy keeping the quantum number $n$ constant. The spin-orbit splitting is
reproduced correctly. It is also seen that $S_{r}+S_{k}$ enhances with
excitation of a fermion in a quantum-mechanical system. Finally, we establish a
relationship of $S_r +S_k$ with the energy of the corresponding single-particle
state i.e. $S_r +S_k = k \ln (\mu E +\nu)$. This relation holds for all the
systems under consideration.

</DOC>
<DOC>
<DOCNO> 120061 </DOCNO>
How Many Galaxies Fit in a Halo? Constraints on Galaxy Formation


  We study galaxy clustering using halo models, where gravitational clustering
is described in terms of dark matter halos. At small scales, clustering
statistics are dominated by halo density profiles, whereas at large scales,
correlations are the result of combining non-linear perturbation theory with
halo biasing. Galaxies are assumed to follow the dark matter profiles, and
galaxy formation efficiency is given by the number of galaxies as a function of
halo mass. This approach leads to generic predictions: the galaxy power
spectrum shows a power-law behavior even though the dark matter does not, and
the galaxy higher-order correlations show smaller amplitudes at small scales
than their dark matter counterparts, as observed in galaxy catalogs. We find
that requiring to fit both the second and third order moments of the APM
galaxies provides a strong constraint on galaxy formation models. The data at
large scales require that galaxy formation be relatively efficient at small
masses, m =10^10 Msun/h, whereas data at smaller scales require that the number
of galaxies in a halo scale as the mass to the 0.8th power in the high-mass
limit. These constraints are independent of those derived from the luminosity
function or Tully-Fisher relation. We also predict the power spectrum,
bispectrum, and higher-order moments of the mass density field. Although halo
models agree well with measurements of the mass power spectrum and the higher
order Sp parameters in N-body simulations, the model assumption that halos are
spherical leads to disagreement in the configuration dependence of the
bispectrum at small scales. We stress the importance of finite volume effects
in higher-order statistics and show how they can be estimated in this approach.

</DOC>
<DOC>
<DOCNO> 151501 </DOCNO>
Conformal Sigma Models for a Class of $T^{p,q}$ Spaces


  We consider a 2-d conformal theory based on (G x G')/ H coset sigma model
introduced by Guadagnini, Martellini and Mintchev. It is shown that in the case
of {SU(2) x SU(2)}/ U(1) the metric of the corresponding background is of
T^{p,q} coset space form (but is not an Einstein one). Similar interpretation
is possible for the Lorentzian coset space W_{4,2}= {SL(2,R) x SL(2,R)}/U(1).
The resulting 10-d homogeneous space metric on W_{4,2} x T^{p,q} supplemented
with 2-form field gives a critical NS-NS superstring background with conformal
sigma model interpretation.

</DOC>
<DOC>
<DOCNO> 119497 </DOCNO>
Slim Disk Model for Narrow-Line Seyfert 1 Galaxies


  We argue that both the extreme soft X-ray excess and the large-amplitude
variability of Narrow-Line Seyfert 1 galaxies (NLS1s) can be explained in the
framework of the slim disk model. When the disk luminosity approaches the
Eddington luminosity, the disk becomes a slim disk, exhibiting a multi-color
blackbody spectrum with a maximum temperature, T(bb), of about 0.2 (M/1e5 solar
masses)e(-1/4) keV, and size of the X-ray emitting region, r(bb), of about R(S)
(the Schwarzschild radius). Furthermore, magnetic energy can be amplified up to
a level exceeding radiation energy emitted from the disk, causing substantial
variability in X-rays by consecutive magnetic flares.

</DOC>
<DOC>
<DOCNO> 70630 </DOCNO>
Tracing Tau-Neutrinos from WIMP-Annihilation


  Accumulation and annihilation of weakly interacting massive particles (WIMPs)
in the earth and the sun may be observed by the resulting neutrino signal. We
demonstrate that, for certain parts of the SUSY parameter space, present and
future neutrino telescopes can expect a higher rate of events due to
tau-neutrinos than of events due to muon-neutrinos. We show how
$\nu_{\tau}\leftrightarrow\nu_{\mu}$ oscillations, and in the case of the sun
also scattering, absorption and regeneration, modify the signal expectation. We
find that most currently proposed neutralino models predict equal or increased
muon fluxes if $\nu_{\tau}\leftrightarrow\nu_{\mu}$ oscillations are included.

</DOC>
<DOC>
<DOCNO> 102528 </DOCNO>
Hypersurface complements, Milnor fibers and minimality of arrangements


  We describe a new relation between the topology of hypersurface complements,
  Milnor fibers and degree of gradient mappings. The main tools are polar
curves and the affine Lefschetz theory developped by H. Hamm and A. N\'emethi.
  In the special case of the hyperplane arrangements, we strengthen some
results due to Orlik and Terao (see Math. Ann.
  301(1995)) and obtain an independant proof for the minimality of hyperplane
arrangements (see Randell math.AT/0011101 for another proof of this result).

</DOC>
<DOC>
<DOCNO> 84862 </DOCNO>
Equations of motion for the mass centers in a scalar theory of


  A scalar theory of gravitation with a preferred reference frame (PRF) is
considered, that accounts for special relativity and reduces to it if the
gravitational field cancels. The gravitating system consists of a finite number
of perfect-fluid bodies. An " asymptotic " post-Newtonian (PN) approximation
scheme is used, allowing an explicit weak-field limit with all fields expanded.
Exact mass centers are defined and their exact equations of motion are derived.
The PN expansion of these equations is obtained: the zero-order equations are
those of Newtonian gravity (NG), and the equations for the first-order (PN)
corrections depend linearly on the PN fields. For PN corrections to the motion
of the mass centers, especially in the solar system, one may assume "
very-well-separated " rigidly moving bodies with spherical self-fields of the
zero-order approximation. The PN corrections reduce then to a time integration
and include spin effects, which might be significant. It is shown that the
Newtonian masses are not correct zero-order masses for the PN calculations. An
algorithm is proposed, in order to minimize the residual and to assess the
velocity in the PRF.

</DOC>
<DOC>
<DOCNO> 117933 </DOCNO>
Quasar variability: correlations with amplitude


  The relation between quasar variability and parameters such as luminosity and
redshift has been a matter of hot debate over the last few years with many
papers on the subject. Any correlations which can be established will have a
profound effect on models of quasar structure and evolution. The sample of
quasars in ESO/SERC field 287 contains over 600 quasars in the range 0 < z <
3.5 and is now large enough to bin in luminosity and redshift, and give
definitive measures of the correlations. We find no significant correlation
between amplitude and redshift, except perhaps at very low redshift, but an
inverse correlation between amplitude and luminosity. This is examined in the
context of various models for quasar variability.

</DOC>
<DOC>
<DOCNO> 152358 </DOCNO>
Domain walls, stabilities, and the mass hierarchy of the Randall-Sundrum


  Randall-Sundrum model, which has a scalar field, is used to investigate the
domain structure of the extra dimension and to obtain a possible solution of
the mass hierarchy problem. It is found that when the domain wall size is
comparable to that of domains, domains become unstable. To construct a reliable
theory, a region of physical parameter space, where domains are stable, is
identified. Analytic forms of field configurations are obtained by perturbative
expansions in term of a small parameter that is approximately equal to the
relative size of domain wall with respect to domains. By placing a single
3-brane in one of the domain, one can solve the mass hierarchy problem.

</DOC>
<DOC>
<DOCNO> 83227 </DOCNO>
A Bayesian Reflection on Surfaces


  The topic of this paper is a novel Bayesian continuous-basis field
representation and inference framework. Within this paper several problems are
solved: The maximally informative inference of continuous-basis fields, that is
where the basis for the field is itself a continuous object and not
representable in a finite manner; the tradeoff between accuracy of
representation in terms of information learned, and memory or storage capacity
in bits; the approximation of probability distributions so that a maximal
amount of information about the object being inferred is preserved; an
information theoretic justification for multigrid methodology. The maximally
informative field inference framework is described in full generality and
denoted the Generalized Kalman Filter. The Generalized Kalman Filter allows the
update of field knowledge from previous knowledge at any scale, and new data,
to new knowledge at any other scale. An application example instance, the
inference of continuous surfaces from measurements (for example, camera image
data), is presented.

</DOC>
<DOC>
<DOCNO> 178443 </DOCNO>
Proton recoil polarization in exclusive (e,e'pp) reactions


  The general formalism of nucleon recoil polarization in the (${\vec
e},e'{\vec N}N$) reaction is given. Numerical predictions are presented for the
components of the outgoing proton polarization and of the polarization transfer
coefficient in the specific case of the exclusive $^{16}$O(${\vec e},e'{\vec
p}p$)$^{14}$C knockout reaction leading to discrete states in the residual
nucleus. Reaction calculations are performed in a direct knockout framework
where final-state interactions and one-body and two-body currents are included.
The two-nucleon overlap integrals are obtained from a calculation of the
two-proton spectral function of $^{16}$O where long-range and short-range
correlations are consistently included. The comparison of results obtained in
different kinematics confirms that resolution of different final states in the
$^{16}$O(${\vec e},e'{\vec p}p$)$^{14}$C reaction may act as a filter to
disentangle and separately investigate the reaction processes due to
short-range correlations and two-body currents and indicates that measurements
of the components of the outgoing proton polarization may offer good
opportunities to study short-range correlations.

</DOC>
<DOC>
<DOCNO> 102590 </DOCNO>
A new look at Hecke's indefinite theta series


  We describe a family of $q$-series generating the space of weight 1 modular
forms coming from indefinite binary quadratic forms and study linear relations
between these series.

</DOC>
<DOC>
<DOCNO> 83268 </DOCNO>
Solaris System Resource Manager: All I Ever Wanted Was My Unfair


  Traditional UNIX time-share schedulers attempt to be fair to all users by
employing a round-robin style algorithm for allocating CPU time. Unfortunately,
a loophole exists whereby the scheduler can be biased in favor of a greedy user
running many short CPU-time processes. This loophole is not a defect but an
intrinsic property of the round-robin scheduler that ensures responsiveness to
the short CPU demands associated with multiple interactive users. A new
generation of UNIX system resource management software constrains the scheduler
to be equitable to all users regardless of the number of processes each may be
running. This "fair-share" scheduling draws on the concept of pro rating
resource "shares" across users and groups and then dynamically adjusting CPU
usage to meet those share proportions. The simple notion of statically
allocating these shares, however, belies the potential consequences for
performance as measured by user response time and service level targets. We
demonstrate this point by modeling several simple share allocation scenarios
and analyzing the corresponding performance effects. A brief comparison of
commercial system resource management implementations from HP, IBM, and SUN is
also given.

</DOC>
<DOC>
<DOCNO> 8300 </DOCNO>
Non-equilibrium Surface Growth and Scalability of Parallel Algorithms


  The scalability of massively parallel algorithms is a fundamental question in
computer science. We study the scalability and the efficiency of a conservative
massively parallel algorithm for discrete-event simulations where the discrete
events are Poisson arrivals. The parallel algorithm is applicable to a wide
range of problems, including dynamic Monte Carlo simulations for large
asynchronous systems with short-range interactions. The evolution of the
simulated time horizon is analogous to a growing and fluctuating surface, and
the efficiency of the algorithm corresponds to the density of local minima of
this surface. In one dimension we find that the steady state of the macroscopic
landscape is governed by the Edwards-Wilkinson Hamiltonian, which implies that
the algorithm is scalable. Preliminary results for higher-dimensional logical
topologies are discussed.

</DOC>
<DOC>
<DOCNO> 12197 </DOCNO>
Macroscopic thermodynamics of equilibrium characterized by power-law


  Macroscopic thermodynamics of equilibrium is constructed for systems obeying
power-law canonical distributions. With this, the connection between
macroscopic thermodynamics and microscopic statistical thermodynamics is
generalized. This is complementary to the Gibbs theorem for the celebrated
exponential canonical distributions of systems in contact with a heat bath.
Thereby, a thermodynamic basis is provided for power-law phenomena ubiquitous
in nature.

</DOC>
<DOC>
<DOCNO> 40525 </DOCNO>
Results on Charmed Meson Spectroscopy from Focus


  We report the preliminary measurement by the FOCUS Collaboration (E831 at
Fermilab) of masses and widths of the L=1 charm mesons D_2^{*0} and D_2^{*+}.

</DOC>
<DOC>
<DOCNO> 11813 </DOCNO>
Observation of a Hard Correlation Gap in Quench-Condensed Ultrathin


  We report on the tunneling density of states (DOS) in ultrathin and strongly
disordered Be films quench-condensed at 20 K. Above 5 K, the DOS shows the
well-known logarithmic anomaly at the Fermi level. Only in a narrow temperature
range near 2 K is the DOS linearly dependent on energy, as predicted by Efros
and Shklovskii. However, both the zero-bias conductance and the slope of the
linear DOS are found to decrease drastically with decreasing temperature.
Tunneling measurements at mK temperatures have revealed conclusively that a
hard correlation gap opens up in the DOS.

</DOC>
<DOC>
<DOCNO> 83298 </DOCNO>
Applying Constraint Handling Rules to HPSG


  Constraint Handling Rules (CHR) have provided a realistic solution to an
over-arching problem in many fields that deal with constraint logic
programming: how to combine recursive functions or relations with constraints
while avoiding non-termination problems. This paper focuses on some other
benefits that CHR, specifically their implementation in SICStus Prolog, have
provided to computational linguists working on grammar design tools. CHR rules
are applied by means of a subsumption check and this check is made only when
their variables are instantiated or bound. The former functionality is at best
difficult to simulate using more primitive coroutining statements such as
SICStus when/2, and the latter simply did not exist in any form before CHR.
  For the sake of providing a case study in how these can be applied to grammar
development, we consider the Attribute Logic Engine (ALE), a Prolog
preprocessor for logic programming with typed feature structures, and its
extension to a complete grammar development system for Head-driven Phrase
Structure Grammar (HPSG), a popular constraint-based linguistic theory that
uses typed feature structures. In this context, CHR can be used not only to
extend the constraint language of feature structure descriptions to include
relations in a declarative way, but also to provide support for constraints
with complex antecedents and constraints on the co-occurrence of feature values
that are necessary to interpret the type system of HPSG properly.

</DOC>
<DOC>
<DOCNO> 119364 </DOCNO>
Accretion disk models and their X-ray reflection signatures. I. Local


  X-ray illumination of accretion disks is an invaluable diagnostic of the
structure of these disks because of the associated iron K$\alpha$ emission.
Here we point out that the resulting reflected spectra depend very sensitively
on the geometry of the X-ray source, and that this fact can be efficiently used
to test these models observationally. In particular, we discuss three different
accretion disk geometries: the ``lamppost model'', accretion disks with
magnetic flares, and the model with a full corona overlying a cold thin disk.
We show that in the case of the lamppost model, unless the X-ray luminosity of
the central source is larger than that of the cold disk by a factor of 10 or
more, a significant fraction of iron in the ionized skin of the disk is in the
hydrogen and helium-like ions. Because these ions have large fluorescence
yields, the resulting reflected spectra look strongly ionized, with Equivalent
Width (EW) of the line {\em increasing} with X-ray luminosity $L_x$ up to the
maximum of $\sim 500$ eV. This situation contrasts to the magnetic flare model,
where the large X-ray flux near flares completely ionizes the skin of the disk
and thus the resulting spectra appear to be that from a neutral material. The
line EW in this model {\em anti-correlates} with X-ray luminosity, and becomes
arbitrarily small when $L_x$ is a good fraction of the Eddington luminosity.
Finally, in the full corona case, due to the additional pressure and weight of
the corona, the gas pressure (and its density) below the corona is always large
enough to make the gas very cool and effectively neutral. No highly ionized
skin forms in such a model. If the corona is Thomson thin, then EW of the line
does not depend on the accretion disk or corona luminosities for the full
corona model.

</DOC>
<DOC>
<DOCNO> 14049 </DOCNO>
Ferromagnetism and large negative magnetoresistance in Pb doped


  Ferromagnetism and accompanying large negative magnetoresistance in
Pb-substituted Bi-Sr-Co-O misfit-layer compound are investigated in detail.
Recent structural analysis of (Bi,Pb)${}_2$Sr${}_{3}$Co${}_2$O${}_9$, which has
been believed to be a Co analogue of
Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+\delta}$, revealed that it has a more complex
structure including a CoO${}_2$ hexagonal layer [T. Yamamoto {\it et al.}, Jpn.
J. Appl. Phys. {\bf 39} (2000) L747]. Pb substitution for Bi not only
introduces holes into the conducting CoO${}_2$ layers but also creates a
certain amount of localized spins. Ferromagnetic transition appears at $T$ =
3.2 K with small spontaneous magnetization along the $c$ axis, and around the
transition temperature large and anisotropic negative magnetoresistance was
observed. This compound is the first example which shows ferromagnetic
long-range order in a two-dimensional metallic hexagnonal CoO${}_2$ layer.

</DOC>
<DOC>
<DOCNO> 119060 </DOCNO>
Tidal dwarf candidates in a sample of interacting galaxies


  We present deep optical B, V, R images of a sample of 10 interacting systems
which were selected for their resemblance to disturbed galaxies at high
redshift. Photometry is performed on knots in the tidal features of the
galaxies. We calculate a grid of evolutionary synthesis models with two
metallicities and various burst strengths for systems consisting of some
fraction of the stellar population of a progenitor spiral plus starburst. By
comparison with two-color diagrams we interpret the photometric data, select
from a total of about 100 condensations 36 star-forming objects that are
located in the tidal features and predict their further evolution. Being more
luminous by 4 mag than normal HII regions we argue that these objects could be
tidal dwarf galaxies or their progenitors, although they differ in number and
mean luminosity from the already known tidal dwarf galaxies typically located
at the end of tidal tails in nearby giant interacting systems. From comparison
with our models we note that all objects show young burst ages. The young
stellar component formed in these tidal dwarf candidates contributes up to 18%
to the total stellar mass at the end of the starburst and dominates the optical
luminosity. This may result in fading by up to 2.5 mag in B during the next 200
Myrs after the burst.

</DOC>
<DOC>
<DOCNO> 69580 </DOCNO>
The glueball spectrum


  Mass ratios of glueballs predicted by the latest Lattice QCD calculations in
the quenched approximation agree well with four prime experimental candidates.

</DOC>
<DOC>
<DOCNO> 71454 </DOCNO>
Semi-Inclusive B\to K(K^*) X Decays with Initial Bound State Effects


  The effects of initial $b$ quark bound state for the semi-inclusive decays
$B\to K(K^*) X$ are studied using light cone expansion and heavy quark
effective theory methods. We find that the initial bound state effects on the
branching ratios and CP asymmetries are small. In the light cone expansion
approach, the CP-averaged branching ratios are increased by about 2% with
respect to the free $b$-quark decay. For $\bar B^0 \to K^- (K^{*-}) X$, the
CP-averaged branching ratios are sensitive to the phase $\gamma$ and the CP
asymmetry can be as large as 7% (14%), whereas for $B^-\to \bar K^0 (\bar
K^{*0})X$ the CP-averaged branching ratios are not sensitive to $\gamma$ and
the CP asymmetries are small ($< 1%$). The CP-averaged branching ratios are
predicted to be in the ranges $(0.53 \sim 1.5)\times 10^{-4}$ [$(0.25 \sim
2.0)\times 10^{-4}$] for $\bar B^0 \to K^- (K^{*-})X$ and $(0.77 \sim
0.84)\times 10^{-4}$ [$(0.67 \sim 0.74)\times 10^{-4}$] for $B^-\to \bar K^0
(\bar K^{*0}) X$, depending on the value of the CP violating phase $\gamma$. In
the heavy quark effective theory approach, we find that the branching ratios
are decreased by about 10% and the CP asymmetries are not affected. These
predictions can be tested in the near future.

</DOC>
<DOC>
<DOCNO> 10311 </DOCNO>
Localization Transition in Multilayered Disordered Systems


  The Anderson delocalization-localization transition is studied in
multilayered systems with randomly placed interlayer bonds of density $p$ and
strength $t$. In the absence of diagonal disorder (W=0), following an
appropriate perturbation expansion, we estimate the mean free paths in the main
directions and verify by scaling of the conductance that the states remain
extended for any finite $p$, despite the interlayer disorder. In the presence
of additional diagonal disorder ($W > 0$) we obtain an Anderson transition with
critical disorder $W_c$ and localization length exponent $\nu$ independently of
the direction. The critical conductance distribution $P_{c}(g)$ varies,
however, for the parallel and the perpendicular directions. The results are
discussed in connection to disordered anisotropic materials.

</DOC>
<DOC>
<DOCNO> 70914 </DOCNO>
Glue in the light-front pion


  It may be possible to approximate the full pion wave function in light-front
QCD using only $q \qbar$ and $q \qbar g$ Fock space components. Removing zero
modes and using invariant-mass cutoffs that make a constituent approximation
possible leads to non-canonical terms in the QCD hamiltonian, and forces us to
work in the broken symmetry phase of QCD in which chiral symmetry breaking
operators must appear directly in the hamiltonian because the vacuum is
trivial. Assuming any candidate interactions are local in the transverse
direction, I argue that they are probably relevant operators so that
perturbation theory is not modified at high energies. Since light-front chiral
symmetry corresponds to quark helicity conservation, we can readily identify
candidate chiral symmetry breaking interactions. The only candidate relevant
operator is the quark-gluon emission/absorption operator with a quark spin
flip. I argue that this operator can only produce the physical $\pi-\rho$ mass
splitting if the $q \qbar g$ component of the pion is significant.

</DOC>
<DOC>
<DOCNO> 12759 </DOCNO>
Nonextensive distribution and factorization of the joint probability


  The problem of factorization of a nonextensive probability distribution is
discussed. It is shown that, in general, the correlation energy between the
correlated subsystems in the canonical composite system can not be neglected
even in the thermodynamic limit. In consequence, the factorization
approximation should be employed carefully according to different systems. It
is also shown that the zeroth law of thermodynamics can be established in the
framework of the Incomplete Statistical Mechanics (ISM).

</DOC>
<DOC>
<DOCNO> 12366 </DOCNO>
BAs and boride III-V alloys


  Boron arsenide, the typically-ignored member of the III-V arsenide series
BAs-AlAs-GaAs-InAs is found to resemble silicon electronically: its Gamma
conduction band minimum is p-like (Gamma_15), not s-like (Gamma_1c), it has an
X_1c-like indirect band gap, and its bond charge is distributed almost equally
on the two atoms in the unit cell, exhibiting nearly perfect covalency. The
reasons for these are tracked down to the anomalously low atomic p orbital
energy in the boron and to the unusually strong s-s repulsion in BAs relative
to most other III-V compounds. We find unexpected valence band offsets of BAs
with respect to GaAs and AlAs. The valence band maximum (VBM) of BAs is
significantly higher than that of AlAs, despite the much smaller bond length of
BAs, and the VBM of GaAs is only slightly higher than in BAs. These effects
result from the unusually strong mixing of the cation and anion states at the
VBM. For the BAs-GaAs alloys, we find (i) a relatively small (~3.5 eV) and
composition-independent band gap bowing. This means that while addition of
small amounts of nitrogen to GaAs lowers the gap, addition of small amounts of
boron to GaAs raises the gap (ii) boron ``semi-localized'' states in the
conduction band (similar to those in GaN-GaAs alloys), and (iii) bulk mixing
enthalpies which are smaller than in GaN-GaAs alloys. The unique features of
boride III-V alloys offer new opportunities in band gap engineering.

</DOC>
<DOC>
<DOCNO> 9344 </DOCNO>
Tumbling Motion of Elliptical Particles in Viscous Two-Dimensional Flow


  The settling dynamics of spherical and elliptical particles in a viscous
Newtonian fluid are investigated numerically using a finite difference
technique. The terminal velocity for spherical particles is calculated for
different system sizes and the extrapolated value for an infinite system size
is compared to the Oseen approximation. Special attention is given to the
settling and tumbling motion of elliptical particles where their terminal
velocity is compared with the one of the surface equivalent spherical particle.

</DOC>
<DOC>
<DOCNO> 151725 </DOCNO>
Wess-Zumino-Witten and fermion models in noncommutative space


  We analyze the connection between Wess-Zumino-Witten and free fermion models
in two-dimensional noncommutative space. Starting from the computation of the
determinant of the Dirac operator in a gauge field background, we derive the
corresponding bosonization recipe studying, as an example, bosonization of the
U(N) Thirring model. Concerning the properties of the noncommutative
Wess-Zumino-Witten model, we construct an orbit-preserving transformation that
maps the standard commutative WZW action into the noncommutative one.

</DOC>
<DOC>
<DOCNO> 119619 </DOCNO>
Time-Dependence of the Mass Accretion Rate in Cluster Cooling Flows


  We analyze two time-dependent cluster cooling flow models in spherical
symmetry. The first assumes that the intracluster gas resides in a static
external potential, and includes the effects of optically thin radiative
cooling and mass deposition. This corresponds to previous steady-state cooling
flow models calculated by White & Sarazin (1987). Detailed agreement is found
between steady-state models and time-dependent models at fixed times in the
simulations. The mass accretion rate is found either to increase or remain
nearly constant once flows reach a steady state. The time rate of change of the
accretion rate is strongly sensitive to the value of the mass deposition
parameter q, but only mildly sensitive to the ratio beta of gravitational
binding energy to gas temperature. We show that previous scaling arguments
presented by Bertschinger (1988) and White (1988) are valid only for mature
cooling flows with weak mass deposition (q ~< 1). The second set of models
includes the effects of a secularly deepening cluster potential and secondary
infall of gas from the Hubble flow. We find that such heating effects do not
prevent the flows from reaching a steady state within an initial central
cooling time.

</DOC>
<DOC>
<DOCNO> 11560 </DOCNO>
Phase fluctuations, dissipation and superfluid stiffness in d-wave


  We study the effect of dissipation on quantum phase fluctuations in d-wave
superconductors. Dissipation, arising from a nonzero low frequency optical
conductivity which has been measured in experiments below $T_c$, has two
effects: (1) a reduction of zero point phase fluctuations, and (2) a reduction
of the temperature at which one crosses over to classical thermal fluctuations.
For parameter values relevant to the cuprates, we show that the crossover
temperature is still too large for classical phase fluctuations to play a
significant role at low temperature. Quasiparticles are thus crucial in
determining the linear temperature dependence of the in-plane superfluid
stiffness. Thermal phase fluctuations become important at higher temperatures
and play a role near $T_c$.

</DOC>
<DOC>
<DOCNO> 119056 </DOCNO>
Double-Peaked Broad Emission Lines in NGC 4450 and Other LINERs


  Spectra taken with HST reveal that NGC 4450 emits Balmer emission lines with
displaced double peaks and extremely high-velocity wings. This characteristic
line profile, previously seen in a few nearby LINERs and in a small fraction of
broad-line radio galaxies, can be interpreted as a kinematic signature of a
relativistic accretion disk. We can reproduce the observed profile with a model
for a disk with a radial range of 1000-2000 gravitational radii and inclined by
27 degrees along the line of sight. The small-aperture HST data also allow us
to detect, for the first time, the featureless continuum at optical wavelengths
in NGC 4450; the nonstellar nucleus is intrinsically very faint, with M_B =
-11.2 mag for D = 16.8 Mpc. We have examined the multiwavelength properties of
NGC 4450 collectively with those of other low-luminosity active nuclei which
possess double-peaked broad lines and find a number of common features. These
objects are all classified spectroscopically as "type 1" LINERs or closely
related objects. The nuclear luminosities are low, both in absolute terms and
relative to the Eddington rates. All of them have compact radio cores, whose
strength relative to the optical nuclear emission places them in the league of
radio-loud active nuclei. The broad-band spectral energy distributions of these
sources are most notable for their deficit of ultraviolet emission compared to
those observed in luminous Seyfert 1 nuclei and quasars. The double-peaked
broad-line radio galaxies Arp 102B and Pictor A have very similar attributes.
We discuss how these characteristics can be understood in the context of
advection-dominated accretion onto massive black holes.

</DOC>
<DOC>
<DOCNO> 120951 </DOCNO>
Spectroscopy of the candidate luminous blue variable at the center of


  We report optical and near-infrared spectra of the central star of the radio
source G79.29+0.46, a candidate luminous blue variable. The spectra contain
numerous narrow (FWHM < 100 km/s emission lines of which the low-lying hydrogen
lines are the strongest, and resemble spectra of other LBVc's and B[e]
supergiants. A few prominent infrared lines are unidentified. The terminal wind
speed is determined from H alpha to be 110 km/s. The strength of H alpha
implies the presence of a very dense wind. Extended emission from H alpha and
[N II] was detected but appears to be associated with the Cygnus X region
rather than the radio source. Both diffuse interstellar bands and interstellar
absorption lines are present in the optical spectrum of the central star,
suggesting that there are both diffuse and molecular cloud components to the
extinction and implying a minimum distance of 1 kpc and minimum luminosity of
\~10^5 L(sun) for the star. The new spectra and their analysis indicate a low
excitation, dense, and slowly expanding wind and support the LBVc
classification.

</DOC>
<DOC>
<DOCNO> 169704 </DOCNO>
An Unentangled Gleason's Theorem


  The purpose of this note is to give a generalization of Gleason's theorem
inspired by recent work in quantum information theory on "nonlocality without
entanglement." For multipartite quantum systems, each of dimension three or
greater, the only nonnegative frame functions over the set of unentangled
states are those given by the standard Born probability rule. However, if one
system is of dimension 2 this is not necessarily the case.

</DOC>
<DOC>
<DOCNO> 10729 </DOCNO>
Computer simulation of the microstructure and rheology of semi-solid


  The rheological behavior of metallic alloys containing both solid and liquid
phases is investigated in the low solid fraction range (<50%). This behavior
depends on both the solid fraction and the shear rate. The concept of Effective
Volume Fraction (EVF) is used to decorrelate the influence of these two
parameters. At high shear rate the slurry behaves like a suspension of hard
spheres, whereas at lower shear rate, particles tend to aggregate in clusters,
entrapping liquid and thus, increasing the EVF and the viscosity. A lattice
model is introduced to simulate the aggregation / break-up processes within a
slurry under shear. When the steady state is reached, the entrapped liquid
fraction is calculated, leading to a viscosity estimation. Simulation results
for the viscosity and 3D cluster structure are in good agreement with
experimental results.

</DOC>
<DOC>
<DOCNO> 100645 </DOCNO>
The Distance Approach to Approximate Combinatorial Counting


  We develop general methods to obtain fast (polynomial time) estimates of the
cardinality of a combinatorially defined set via solving some randomly
generated optimization problems on the set. Geometrically, we estimate the
cardinality of a subset of the Boolean cube via the average distance from a
point in the cube to the subset. As an application, we present a new randomized
polynomial time algorithm which approximates the permanent of a 0-1 matrix by
solving a small number of Assignment problems.

</DOC>
<DOC>
<DOCNO> 99558 </DOCNO>
L^2-Riemann-Roch Inequalities for Covering Manifolds


  We study the existence of $L^2$ holomorphic sections of invariant line
bundles over Galois coverings of Zariski open sets in Moishezon manilolds. We
show that the von Neuman dimension of the space of $L^2$ holomorphic sections
is bounded below under reasonable curvature conditions. We also give criteria
for a a compact complex space with isolated singularities and some related
strongly pseudoconcave manifolds to be Moishezon. Their coverings are then
studied with the same methods. As applications we give weak Lefschetz theorems
using the Napier--Ramachandran proof of the Nori theorem.

</DOC>
<DOC>
<DOCNO> 118614 </DOCNO>
The MONS Star Trackers


  The MONS satellite will have two Star Trackers to sense the spacecraft
attitude, and we plan to use them as scientific instruments to perform
high-precision photometry of thousands of stars. We briefly describe the
current plans for the Star Trackers and their expected capabilities.

</DOC>
<DOC>
<DOCNO> 85453 </DOCNO>
Solutions with negative mass for the SU(2) Einstein-Yang-Mills equations


  The aim of this note is to clarify the structure of nontrivial global
solutions with nonpositive ADM mass for the static, spherically symmetric
Einstein-Yang-Mills equations with SU(2) gauge group. The presented numerical
results demonstrate that these solutions have zero number of nodes of the gauge
field function. This is a feature that is present neither for particlelike nor
for black hole solutions.

</DOC>
<DOC>
<DOCNO> 14082 </DOCNO>
Signatures of Spin Degrees of Freedom in Charge Dynamics of


  Charge carrier-spin excitation spectral densities constructed from optical
data and varying with temperature are used to calculate various properties of
the charge carrier dynamics. Temperature (T) variations of such properties are
sensitive to the changes in the spectral density brought about by the growth in
the 41 meV spin resonance as T is lowered. The microwave conductivity and the
thermal conductivity are stressed and comparison with experiment is given. The
imaginary part of the conductivity as a function of frequency \omega is also
featured.

</DOC>
<DOC>
<DOCNO> 99769 </DOCNO>
Computation of Cohomology of Lie Superalgebras of Vector Fields


  The cohomology of Lie (super)algebras has many important applications in
mathematics and physics. It carries most fundamental ("topological")
information about algebra under consideration. At present, because of the need
for very tedious algebraic computation, the explicitly computed cohomology for
different classes of Lie (super)algebras is known only in a few cases. That is
why application of computer algebra methods is important for this problem. We
describe here an algorithm and its C implementation for computing the
cohomology of Lie algebras and superalgebras. The program can proceed
finite-dimensional algebras and infinite-dimensional graded algebras with
finite-dimensional homogeneous components. Among the last algebras Lie algebras
and superalgebras of formal vector fields are most important. We present some
results of computation of cohomology for Lie superalgebras of Buttin vector
fields and related algebras. These algebras being super-analogs of Poisson and
Hamiltonian algebras have found many applications to modern supersymmetric
models of theoretical and mathematical physics.

</DOC>
<DOC>
<DOCNO> 80842 </DOCNO>
A nonperturbative determination of cA


  We describe a non-perturbative determination of $c_A$ using correlators
containing the axial-vector and pseudoscalar currents at zero and non-zero
momentum. We apply the method of Bhattacharya et al to extract $c_A$ from the
requirement that the ratio of appropriate correlators for the PCAC relation
becomes independent of time in the excited state region. We find that the
result depends strongly on the order of the derivatives used in the PCAC
relation. We also find that, using the lowest order derivatives, we cannot get
a consistent value of $c_A$ between zero and non-zero momentum cases. The $c_A$
values that we obtain as we improve the derivatives are consistent and decrease
in magnitude heading towards the perturbative result.

</DOC>
<DOC>
<DOCNO> 178449 </DOCNO>
The $\eta NN$ coupling constant


  We derive the light cone QCD sum rule for the $\eta NN$ coupling constant
$g_{\eta NN} $. The contribution from the excited states and the continuum is
subtracted cleanly through the double Borel transform with respect to the two
external momenta, $p_1^2$, $p_2^2=(p-q)^2$. Our result is $\alpha_{\eta
NN}=(0.3\pm 0.15)$, which favors small values used in literatures.

</DOC>
<DOC>
<DOCNO> 122949 </DOCNO>
Systematic Errors in the Estimation of Black Hole Masses by


  The mass of the central black hole in many active galactic nuclei has been
estimated on the basis of the assumption that the dynamics of the broad
emission line gas are dominated by the gravity of the black hole. The most
commonly-employed method is to estimate a characteristic size-scale $r_*$ from
reverberation mapping experiments and combine it with a characteristic velocity
$v_*$ taken from the line profiles; the inferred mass is then estimated by $r_*
v_*^2/G$. We critically discuss the evidence supporting the assumption of
gravitational dynamics and find that the arguments are still inconclusive. We
then explore the range of possible systematic error if the assumption of
gravitational dynamics is granted. Inclination relative to a flattened system
may cause a systematic underestimate of the central mass by a factor $\sim
(h/r)^2$, where $h/r$ is the aspect ratio of the flattening. The coupled
effects of a broad radial emissivity distribution, an unknown angular radiation
pattern of line emission, and sub-optimal sampling in the reverberation
experiment can cause additional systematic errors as large as a factor of 3 or
more in either direction.

</DOC>
<DOC>
<DOCNO> 117720 </DOCNO>
Evolution of D and 3He in the Galaxy


  The predictions of Galactic chemical evolution models for D and $^3$He are
described in connection with those on the other Galactic quantities for which
observational constraints are available.
  Models in agreement with the largest set of data predict deuterium depletions
from the Big Bang to the present epoch smaller than a factor of 3 and do not
allow for D/H primordial abundances larger than $\sim4\times10^{-5}$. Models
predicting higher D consumption do not reproduce other observed features of our
Galaxy.
  If both the primordial D and $^3$He are low, models assuming that 90% of
low-mass stars experience an extra-mixing during the red giant phase reproduce
all the $^3$He observed abundances. The same percentage allows to fit also the
observed carbon isotopic ratios, thus supporting the self-consistency of the
extra-mixing mechanism.

</DOC>
<DOC>
<DOCNO> 118288 </DOCNO>
The Formation of the Hubble Sequence of Disk Galaxies: The Effects of


  We investigate a model of disk galaxies whereby viscous evolution of the
gaseous disk drives material inwards to form a proto-bulge. We start from the
standard picture of disk formation through the settling of gas into a dark halo
potential well, with the disk initially coming into centrifugal equilibrium
with detailed conservation of angular momentum. We derive generic analytic
solutions for the disk-halo system after adiabatic compression of the dark
halo, with free choice of the input virialized dark halo density profile and of
the specific angular momentum distribution. We derive limits on the final
density profile of the halo in the central regions. Subsequent viscous
evolution of the disk is modelled by a variation of the specific angular
momentum distribution of the disk, providing analytic solutions to the final
disk structure. The assumption that the viscous evolution timescale and star
formation timescale are similar leads to predictions of the properties of the
stellar components. Focusing on small `exponential' bulges, ones that may be
formed through a disk instability, we investigate the relationship between the
assumed initial conditions, such as halo `formation', or assembly, redshift
$z_f$, spin parameter $\lambda$, baryonic fraction $F$, and final disk
properties such as global star formation timescale, gas fraction, and
bulge-to-disk ratio. We find that the present properties of disks, such as the
scale length, are compatible with a higher initial formation redshift if the
re-distribution by viscous evolution is included than if it is ignored. We also
quantify the dependence of final disk properties on the ratio $F/\lambda$, thus
including the possibility that the baryonic fraction varies from galaxy to
galaxy, as perhaps may be inferred from the observations.

</DOC>
<DOC>
<DOCNO> 71900 </DOCNO>
Lattice simulations of QCD-like theories at non-zero density


  One way of avoiding the complex action problem in lattice QCD at non-zero
density is to simulate QCD-like theories with a real action, such as two-colour
QCD. The symmetries of two-colour QCD with quarks in the fundamental and in the
adjoint representation are described, and the status of lattice simulations is
reviewed, with particular emphasis on comparison with predictions from chiral
perturbation theory. Finally, we discuss how the lessons from two-colour QCD
may be carried over to physical QCD.

</DOC>
<DOC>
<DOCNO> 10177 </DOCNO>
Field Theory of N Entangled Polymers


  We formulate a field theory capable of describing the entanglement in a
canonical ensemble of N polymers in terms of Feynman diagrams.

</DOC>
<DOC>
<DOCNO> 8696 </DOCNO>
On the kernel of tree incidence matrices


  We study the height of the delta peak at 0 in the spectrum of random tree
incidence matrices. We show that the average fraction of the spectrum occupied
by the eigenvalue 0 in a large random tree is asymptotic to 2x-1 =
0.1342865808195677459999... where x is the unique real root of x = exp(-x). For
finite trees, we give a closed form, a generating function, and an asymptotic
estimate for the sequence 1,0,3,8,135,1164,21035,.... of the total multiplicity
of the eigenvalue 0 in the set of n^{n-2} tree incidence matrices of size n>0.

</DOC>
<DOC>
<DOCNO> 116759 </DOCNO>
Loading a vapor cell magneto-optic trap using light-induced atom


  Low intensity white light was used to increase the loading rate of $^{87}$Rb
atoms into a vapor cell magneto-optic trap by inducing non-thermal desorption
of Rb atoms from the stainless steel walls of the vapor cell. An increased Rb
partial pressure reached a new equilibrium value in less than 10 seconds after
switching on the broadband light source. After the source was turned off, the
partial pressure returned to its previous value in $1/e$ times as short as 10
seconds.

</DOC>
<DOC>
<DOCNO> 150809 </DOCNO>
Brane Dynamics in Background Fluxes and Non-commutative Geometry


  Branes in non-trivial backgrounds are expected to exhibit interesting
dynamical properties. We use the boundary conformal field theory approach to
study branes in a curved background with non-vanishing Neveu-Schwarz 3-form
field strength. For branes on an $S^3$, the low-energy effective action is
computed to leading order in the string tension. It turns out to be a field
theory on a non-commutative `fuzzy 2-sphere' which consists of a Yang-Mills and
a Chern-Simons term. We find a certain set of classical solutions that have no
analogue for flat branes in Euclidean space. These solutions show, in
particular, how a spherical brane can arise as bound state from a stack of
D0-branes.

</DOC>
<DOC>
<DOCNO> 100770 </DOCNO>
Rigged Hilbert Spaces associated with Misra-Prigogine-Courbage Theory of


  It is proved that, in the Misra-Prigogine-Courbage Theory of Irreversibility
using the Internal Time superoperator, fixing its associated non-unitary
transformation $\Lambda$, amounts to rigging the corresponding
Hilbert-Liouville space. More precisely, it is demonstrated that any $\Lambda $
determinates three canonical riggings of the Liouville space $\QTR{cal}{L}$: a
first one with a Hilbert space with a norm greater than the relative one from
$\QTR{cal}{L}$; a second one with a $\sigma $-Hilbertian space, which is a
K\"{o}the space if $\Lambda$ is compact and is a nuclear space if $\Lambda$ has
certain nuclear properties; and finally a third one with a smaller $\sigma
$-Hilbertian space with a still stronger topology which is nuclear if $\Lambda
^{n}$ is Hilbert-Schmidt, for some positive integer n. Viceversa: any rigging
of this type, originated in a dynamical system having an Internal Time
superoperator, defines a $\Lambda$ in a canonical way.

</DOC>
<DOC>
<DOCNO> 121129 </DOCNO>
Multiwaveband studies of the hard ROSAT SMC transient 1WGA J0053.8-7226:


  We report on two optical candidates for the counterpart to an X-ray source in
the SMC, 1WGA J0053.8-7226, identified as a serendipitous X-ray source from the
ROSAT PSPC archive, and also observed by the Einstein IPC. Its X-ray
properties, namely the hard X-ray spectrum, flux variability and column density
indicate a hard, transient source, with a luminosity of 3.8 x 10E35 ergs/sec.
XTE and ASCA observations have confirmed the source to be an X-ray pulsar, with
a 46 s spin period. Our optical observations reveal two possible candidates
within the error circle. Both exhibit strong H alpha and weaker H beta
emission. The optical colours indicate that both objects are Be-type stars. The
Be nature of the stars implies that the counterpart is most likely a Be/X-ray
binary system. Subsequent IR photometry JHK of one of the objects shows the
source varies by at least 0.5 mag, while the (J-K) measured nearly
simultaneously with the UBVRI and spectroscopic observations indicate an
IR-excess of approximately 0.3 magnitudes.

</DOC>
<DOC>
<DOCNO> 39928 </DOCNO>
Neutrino Radiation Challenges and Proposed Solutions for Many-TeV Muon


  Neutrino radiation is expected to impose major design and siting constraints
on many-TeV muon colliders. Previous predictions for radiation doses at TeV
energy scales are briefly reviewed and then modified for extension to the
many-TeV energy regime. The energy-cubed dependence of lower energy colliders
is found to soften to an increase of slightly less than quadratic when averaged
over the plane of the collider ring and slightly less than linear for the
radiation hot spots downstream from straight sections in the collider ring.
Despite this, the numerical values are judged to be sufficiently high that any
many-TeV muon colliders will likely be constructed on large isolated sites
specifically chosen to minimize or eliminate human exposure to the neutrino
radiation. It is pointed out that such sites would be of an appropriate size
scale to also house future proton-proton and electron-positron colliders at the
high energy frontier, which naturally leads to conjecture on the possibilities
for a new world laboratory for high energy physics. Radiation dose predictions
are also presented for the speculative possibility of linear muon colliders.
These have greatly reduced radiation constraints relative to circular muon
colliders because radiation is only emitted in two pencil beams directed along
the axes of the opposing linacs.

</DOC>
<DOC>
<DOCNO> 9329 </DOCNO>
Dynamics of the Bose-Einstein condensate: quasi-one-dimension and beyond


  It is shown that the quasi-one-dimensional Bose-Einstein condensate is
experimentally accessible and rich in intriguing phenomena. We demonstrate
numerically and analytically the existence, stability, and perturbation-induced
dynamics of all types of stationary states of the quasi-one-dimensional
nonlinear Schrodinger equation for both repulsive and attractive cases. Among
our results are: the connection between stationary states and solitons;
creation of vortices from such states; manipulation of such states with simple
phase profiles; demonstration of the fragility of the condensate phase in
response to shock; and a robust stabilization of the attractive Bose-Einstein
condensate.

</DOC>
<DOC>
<DOCNO> 11091 </DOCNO>
Gauge Invariant Bosonization of Quantum Hall Systems and Skyrmions :


  We develop a systematic semiclassical approximation scheme for quantum Hall
skyrmions near filling factors $\nu = {1 \over 2n+1}$, which is exact in the
long wavelength limit. We construct a coherent state basis for the Hilbert
space of Chern-Simons gauge fields and composite bosons with spin. These states
are projected to the physical gauge invariant subspace and their wavefunctions
explicitly evaluated. The lowest Landau level (LLL) condition is shown to be
equivalent to an analyticity condition on the parameters.
  The matrix elements of physical observables between these states are shown to
be calculable in the limit of small amplitude long wavelength density
fluctuations. The electric charge density is shown to be proportional to the
toplological charge density if and only if the LLL condition is satisfied.
  We then show that these states themselves form a generalised coherent state
basis, parameterised by the values of physical observables. The theory can
therefore be written in terms of these gauge invariant bosonic fields in the
long wavelength regime. The off diagonal matrix elements of observables in
these coherent states are computed and shown to vanish in the long wavelength
limit. Thus we are able to prove that the classical description of the skyrmion
is exact in the limit of large skyrmions.

</DOC>
<DOC>
<DOCNO> 12158 </DOCNO>
Parafermion Hall states from coset projections of abelian conformal


  The Z_k-parafermion Hall state is an incompressible fluid of k-electron
clusters generalizing the Pfaffian state of paired electrons. Extending our
earlier analysis of the Pfaffian, we introduce two ``parent'' abelian Hall
states which reduce to the parafermion state by projecting out some neutral
degrees of freedom. The first abelian state is a generalized (331) state which
describes clustering of k distinguishable electrons and reproduces the
parafermion state upon symmetrization over the electron coordinates. This
description yields simple expressions for the quasi-particle wave functions of
the parafermion state. The second abelian state is realized by a conformal
theory with a (2k-1)-dimensional chiral charge lattice and it reduces to the
Z_k-parafermion state via the coset construction su(k)_1+su(k)_1/su(k)_2. The
detailed study of this construction provides us a complete account of the
excitations of the parafermion Hall state, including the field identifications,
the Z_k symmetry and the partition function.

</DOC>
<DOC>
<DOCNO> 121504 </DOCNO>
Scaling properties of the redshift power spectrum: theoretical models


  We report the results of an analysis of the redshift power spectrum
$P^S(k,\mu)$ in three typical Cold Dark Matter (CDM) cosmological models, where
$\mu$ is the cosine of the angle between the wave vector and the line-of-sight.
Two distinct biased tracers derived from the primordial density peaks of
Bardeen et al. and the cluster-underweight model of Jing, Mo, & B\"orner are
considered in addition to the pure dark matter models. Based on a large set of
high resolution simulations, we have measured the redshift power spectrum for
the three tracers from the linear to the nonlinear regime. We investigate the
validity of the relation - guessed from linear theory - in the nonlinear regime
$$ P^S(k,\mu)=P^R(k)[1+\beta\mu^2]^2D(k,\mu,\sigma_{12}(k)), $$ where $P^R(k)$
is the real space power spectrum, and $\beta$ equals $\Omega_0^{0.6}/b_l$. The
damping function $D$ which should generally depend on $k$, $\mu$, and
$\sigma_{12}(k)$, is found to be a function of only one variable
$k\mu\sigma_{12}(k)$. This scaling behavior extends into the nonlinear regime,
while $D$ can be accurately expressed as a Lorentz function - well known from
linear theory - for values $D > 0.1$. The difference between $\sigma_{12}(k)$
and the pairwise velocity dispersion defined by the 3-D peculiar velocity of
the simulations (taking $r=1/k$) is about 15%. Therefore $\sigma_{12}(k)$ is a
good indicator of the pairwise velocity dispersion. The exact functional form
of $D$ depends on the cosmological model and on the bias scheme. We have given
an accurate fitting formula for the functional form of $D$ for the models
studied.

</DOC>
<DOC>
<DOCNO> 178829 </DOCNO>
Continuum QCD and light mesons


  The ladder-rainbow truncation of the set of Dyson-Schwinger equations is used
to study light mesons. The parameters in the effective interaction are
constrained by the chiral condensate and f_\pi; the current quark masses are
fitted to m_\pi and m_K. The dressed quark propagators are in qualitative
agreement with recent lattice-QCD results at low q^2 while having the correct
perturbative behavior at large q^2. The resulting vector meson masses are
within 5% of the experimental values. The obtained electromagnetic form factors
and strong and electroweak coupling constants are also in good agreement with
the data. At finite temperature, this truncation leads to a mean-field chiral
phase transition. The spatial pion mass is almost constant below this
transition, but rises with T close to and above T_c. The mass of its chiral
partner, an idealized sigma meson, decreases with T until T_c, where it becomes
degenerate with the pion.

</DOC>
<DOC>
<DOCNO> 122817 </DOCNO>
Microquasars: Open Questions and Future Perspectives


  The discovery and subsequent study of microquasars lead to major progress in
our understanding of: 1) the nature of relativistic jets seen elsewhere in the
universe, and 2) the connection between the accretion onto compact objects and
the formation of collimated jets. A detailed account of the major progress
accomplished until present was published in Annual Review of Astronomy &
Astrophysics (Mirabel & Rodr\'\i guez, 1999). Here I review the questions that
remain unanswered, as well as the future perspectives that this new field of
research is opening.

</DOC>
<DOC>
<DOCNO> 70415 </DOCNO>
Next-to-next-to-leading logarithmic corrections at small transverse


  We study the region of small transverse momenta in qqbar- and gg-initiated
processes with no colored particle detected in the final state. We present the
universal expression of the O(alpha_s^2) logarithmically enhanced contributions
up to next-to-next-to-leading logarithmic accuracy. From there we extract the
coefficients that allow the resummation of the large logarithmic contributions.
We find that the coefficient known in the literature as B^{(2)} is process
dependent, since it receives a hard contamination from the one loop correction
to the leading order subprocess. We present the general result of B^{(2)} for
both quark and gluon channels. In particular, in the case of Higgs production,
this result will be relevant to improve the matching between resummed
predictions and fixed order calculations.

</DOC>
<DOC>
<DOCNO> 71466 </DOCNO>
FCNC in SUSY models with non-universal A-terms


  We study the inclusive branching ratio for B-> X_s gamma in a class of
string-inspired SUSY models with non-universal soft-breaking A-terms. We show
that b->s gamma do not severely constrain the non-universality of these models
and the parameter regions which are important for generating sizeable
contribution to epsilon'/epsilon, of order 2 x10^(-3), are not excluded. We
also show that the CP asymmetry of this decay is predicted to be much larger
than the standard model prediction in a wide region of the parameter space. In
particular, it can be of order 10-15% which can be accessible at B factories.

</DOC>
<DOC>
<DOCNO> 150638 </DOCNO>
Reflection Amplitudes in Non-Simply Laced Toda Theories and


  We study the ultraviolet asymptotics in non-simply laced affine Toda theories
considering them as perturbed non-affine Toda theories, which possess the
extended conformal symmetry. We calculate the reflection amplitudes, in
non-affine Toda theories and use them to derive the quantization condition for
the vacuum wave function, describing zero-mode dynamics. The solution of this
quantization conditions for the ground state energy determines the UV
asymptotics of the effective central charge. These asymptotics are in a good
agreement with Thermodynamic Bethe Ansatz(TBA) results. To make the comparison
with TBA possible, we give the exact relations between parameters of the action
and masses of particles as well as the bulk free energies for non-simply laced
affine Toda theories.

</DOC>
<DOC>
<DOCNO> 71574 </DOCNO>
Meson Effects on Chiral Condensate at Finite Density


  Meson corrections on chiral condensate up to next-to-leading order in $1/N_c$
expansion at finite density are investigated in NJL model with chiral symmetry
explicitly breaking. Compared with the mean-field results, the chiral phase
transition is still of first order, while the properties at the critical
density of chiral phase transition are found to change significantly.

</DOC>
<DOC>
<DOCNO> 170624 </DOCNO>
Reply to the comment on `` Manipulating the frequency-entangled states


  In the paper [1], authors claim that the scheme for entanglement swapping
using an acoustic-optical modulator [2] is flaw. In this reply, we show there
is a trivial mistake in the scheme [2], but the main conclusion is still
correct, that is, the acoustic-optical modulator can be used to manipulate the
frequency-entangled state.

</DOC>
<DOC>
<DOCNO> 122935 </DOCNO>
Jet directions in Seyfert galaxies: Radio continuum imaging data


  We present the results of VLA A-array 8.46 GHz continuum imaging of 55
Seyfert galaxies (19 Seyfert 1's and 36 Seyfert 2's). These galaxies are part
of a larger sample of 88 Seyfert galaxies, selected from mostly isotropic
properties, the flux at 60 mum and warm infrared 25 mum to 60 mum colors. These
images are used to study the structure of the radio continuum emission of these
galaxies and their position angles, in the case of extended sources. These
data, combined with information from broad-band B and I observations, have been
used to study the orientation of radio jets relative to the plane of their host
galaxies (Kinney et al. 2000).

</DOC>
<DOC>
<DOCNO> 169978 </DOCNO>
Berry phase for a potential well transported in a homogeneous magnetic


  We consider a two-dimensional particle of charge $e$ interacting with a
homogeneous magnetic field perpendicular to the plane and a potential well
which is transported along a closed loop in the plane. We show that a bound
state corresponding to a simple isolated eigenvalue acquires at that Berry's
phase equal to $2\pi {\rm sgn} e$ times the number of flux quanta through the
oriented area encircled by the loop. We also argue that this is a purely
quantum effect since the corresponding Hannay angle is zero.

</DOC>
<DOC>
<DOCNO> 10753 </DOCNO>
Mesoscopic Tunneling Magnetoresistance


  We study spin-dependent transport through
ferromagnet/normal-metal/ferromagnet double tunnel junctions in the mesoscopic
Coulomb blockade regime. A general transport equation allows us to calculate
the conductance in the absence or presence of spin-orbit interaction and for
arbitrary orientation of the lead magnetizations. The tunneling
magnetoresistance (TMR), defined at the Coulomb blockade conductance peaks, is
calculated and its probability distribution presented. We show that mesoscopic
fluctuations can lead to the optimal value of the TMR.

</DOC>
<DOC>
<DOCNO> 152547 </DOCNO>
Target-space anomalies and elliptic indices in heterotic orbifolds


  We present a complete string theory analysis of all mixed gauge,
gravitational and target-space anomalies potentially arising in the simplest
heterotic Z_N orbifold models, with N odd and standard embedding. These
anomalies turn out to be encoded in an elliptic index, which can be easily
computed; they are found to cancel through a universal GS mechanism induced by
the dilaton multiplet. The target-space symmetry is then shown to have a nice
geometric interpretation in terms of torsion, and the target-space dependence
of the four-dimensional GS couplings can be alternatively rederived from the
implicit torsion dependence of the standard ten-dimensional GS couplings. The
result is universal and consists essentially of a Bianchi identity for the NSNS
B field depending on all the curvatures, and in particular on the target-space
curvature.

</DOC>
<DOC>
<DOCNO> 11203 </DOCNO>
Absence of Bose-Einstein condensation with a uniform field and contact


  The behavior of a Bose-Einstein ideal gas of particles in a three dimensional
space in the presence of a uniform field, such as gravity, and of contact
interaction, describing the presence of one impurity, is investigated. It is
shown that Bose-Einstein condensation can not occur.

</DOC>
<DOC>
<DOCNO> 117712 </DOCNO>
Power Density Spectra of GRBs


  Power density spectra (PDSs) of long gamma-ray bursts (GRBs) provide useful
information on GRBs, indicating their self-similar temporal structure. The best
power-law PDSs are displayed by the longest bursts (T_90>100 s) in which the
range of self-similar time scales covers more than 2 decades. Shorter bursts
have apparent PDS slopes more strongly affected by statistical fluctuations.
The underlying power law can then be reproduced with high accuracy by averaging
the PDSs for a large sample of bursts. This power law has a slope approximately
equal to -5/3 and a sharp break at about 1 Hz.
  The power-law PDS provides a new sensitive tool for studies of GRBs. In
particular, we calculate the PDSs of bright bursts in separate energy channels.
The PDS flattens in the hard channel (h\nu>300 keV) and steepens in the soft
channel (h\nu<50 keV), while the PDS of bolometric light curves approximately
follows the -5/3 law.
  We then study dim bursts and compare them to the bright ones. We find a
strong correlation between the burst brightness and the PDS slope. This
correlation shows that the bursts are far from being standard candles and dim
bursts should be intrinsically weak. The time dilation of dim bursts is
probably related to physical processes occurring in the burst rather than to a
cosmological redshift.

</DOC>
<DOC>
<DOCNO> 70186 </DOCNO>
R-mediation of Dynamical Supersymmetry Breaking


  We propose a simple scenario of the dynamical supersymmetry breaking in four
dimensional supergravity theories. The supersymmetry breaking sector is assumed
to be completely separated as a sequestered sector from the visible sector,
except for the communication by the gravity and U(1)_R gauge interactions, and
the supersymmetry breaking is mediated by the superconformal anomaly and U(1)_R
gauge interaction. Supersymmetry is dynamically broken by the interplay between
the non-perturbative effect of the gauge interaction and Fayet-Iliopoulos
D-term of U(1)_R which necessarily exists in supergravity theories with gauged
U(1)_R symmetry. We construct an explicit model which gives phenomenologically
acceptable mass spectrum of superpartners with vanishing (or very small)
cosmological constant.

</DOC>
<DOC>
<DOCNO> 12822 </DOCNO>
Linked Cluster Series Expansions for Two-Particle Bound States


  We develop strong-coupling series expansion methods to study two-particle
spectra of quantum lattice models. At the heart of the method lies the
calculation of an effective Hamiltonian in the two-particle subspace. We
explicitly consider an orthogonality transformation to generate this block
diagonalization, and find that maintaining orthogonality is crucial for systems
where the ground state and the two-particle subspace are characterized by
identical quantum numbers. We discuss the solution of the two-particle
Schr\"odinger equation by using a finite lattice approach in coordinate space
or by an integral equation in momentum space. These methods allow us to
precisely determine the low-lying excitation spectra of the models at hand,
including all two-particle bound/antibound states. Further, we discuss how to
generate series expansions for the dispersions of the bound/antibound states.
These allow us to employ series extrapolation techniques, whereby binding
energies can be determined even when the expansion parameters are not small. We
apply the method to the (1+1)D transverse Ising model and the two-leg
spin-$\case 1/2$ Heisenberg ladder. For the latter model, we also calculate the
coherence lengths and determine the critical properties where bound states
merge with the two-particle continuum.

</DOC>
<DOC>
<DOCNO> 99812 </DOCNO>
Polarizations on abelian varieties


  The results in this paper imply that for every number field F and positive
integer r, there exists an F-isogeny class of abelian varieties such that r
divides the degree of every F-polarization on every abelian variety in the
isogeny class.

</DOC>
<DOC>
<DOCNO> 11556 </DOCNO>
Boundary Conditions in Diffusional Growth and Sedimentation


  In many applications, transport of particles can be described by the
diffusion equation, or its convective-diffusion generalizations, in part of
three-dimensional space. In particular, in surface deposition or in growth of
aggregates or sediments, particles in the suspension outside the surface or
aggregate boundary can be considered as diffusing under the influence of
applied forces, such as the double-layer interactions or gravity. However, the
diffusion equation cannot be used at the substrate or inside the aggregate. One
convenient and widely used approach has been to impose boundary conditions at
the surface, to supplement and completely define the diffusion problem outside
it. This short survey describes some theoretical results on the use of such
boundary conditions and their physical interpretation.

</DOC>
<DOC>
<DOCNO> 101729 </DOCNO>
Bound - states for truncated Coulomb potentials


  The pseudoperturbative shifted - $l$ expansion technique PSLET is generalized
for states with arbitrary number of nodal zeros. Bound- states energy
eigenvalues for two truncated coulombic potentials are calculated using PSLET.
In contrast with shifted large-N expansion technique, PSLET results compare
excellently with those from direct numerical integration.

</DOC>
<DOC>
<DOCNO> 71593 </DOCNO>
Recent developments in chiral perturbation theory


  I briefly review the current status of chiral perturbation theory in the
meson sector. Emphasis is given on the quest for higher precision. I discuss
two examples: one where it is difficult to make a good prediction (K_L -> pi^0
gamma gamma), and where CHPT, even when pushed to higher orders, cannot yield
an increase in accuracy. The second one is pi pi scattering where a very sharp
prediction can be made by combining CHPT at the two-loop level with dispersion
relations

</DOC>
<DOC>
<DOCNO> 178903 </DOCNO>
Reaction and break-up cross sections of 11Li at 0.8 and 0.28 GeV/u


  In this paper we calculate reaction and breakup cross sections for the two-
neutron halo nucleus of $^{11}$Li using the optical limit of Glauber theory.
Calculations are presented and compared to experimental data at 0.8 and 0.28
GeV/u on a series of targets. The $^{11}$Li nucleus is described as a
three-body system, a core plus two neutrons, with a phenomenological
neutron-core potential and a density dependent neutron-neutron interaction of
zero range. Three different wave functions are constructed which have different
$(2s_{1/2})^2$ and $(1p_{1/2})^2$ two-neutron components but correspond to the
same binding energy close to the experimental value. We show that the agreement
with all the experimental observables is achieved only if the 11Li wave
function contains about 30% of $(2s_{1/2})^2$ configuration.

</DOC>
<DOC>
<DOCNO> 100791 </DOCNO>
Smooth spectral transition from Coulomb to oscillator


  Non-relativistic potential models are considered of the pure power V(r) =
sgn(q) r^q and logarithmic V(r) = ln(r) types. Envelope representations and
kinetic potentials are employed to show that these potentials are actually in a
single family. The log spectra can be obtained from the power spectra by the
limit q --> 0 taken in a smooth representation P_{n\ell}(q) for the eigenvalues
E_{n\ell}(q). A simple approximation formula is developed which yields the
first thirty eigenvalues with error < 0.04%. Extensions to potentials with
linear combinations of terms such as -a/r + br and applications to
spatially-symmetric few-body problems are discussed.

</DOC>
<DOC>
<DOCNO> 12189 </DOCNO>
Comment on ``Anomalous crossover between thermal and shot noise in


  Shot noise is not normally evident in bulk solid-state conductors, since it
is strongly attenuated by inelastic collisions. The ``anomalous'' emergence of
macroscopic shot noise is discussed in G. Gomila and L. Reggiani, Phys. Rev. B
62, 8068 (2000). We remark on the consistency of this linear diffusive model at
the large voltages and currents needed to see the effect.

</DOC>
<DOC>
<DOCNO> 11946 </DOCNO>
Charge Pumping and Photovoltaic effect in Open Quantum Dots


  We propose a random matrix theory to describe the influence of a
time-dependent external field on electron transport through open quantum dots.
We describe the generation of the current by an oscillating field for the dot,
connected to two leads with equal chemical potentials. For low frequency fields
our results correspond to adiabatic charge pumping. Finite current can be
produced if the system goes along a closed loop in parameter space, which
covers a finite area. At high frequency finite current is produced even if the
loop is a line in parameter space. This result can be explained in the same way
as adiabatic pumping but considering the evolution of the system in phase space
rather than in parametric space.

</DOC>
<DOC>
<DOCNO> 85485 </DOCNO>
Radiation from a uniformly accelerated charge in the outskirts of a


  Using traversable wormholes as theoretical background, we revisit a deep
question of general relativity: Does a uniformly accelerated charged particle
radiate? We particularize to the recently proposed gravitational \v{C}erenkov
radiation, that happens when the spatial part of the Ricci tensor is negative.
If $^{^{(3+1)}}R^i_{\phantom{i}i}< 0$, the matter threading the gravitational
field violates the weak energy condition. In this case, the effective
refractive index for light is bigger than 1, i.e. particles propagates, in that
medium, faster than photons. This leads to a violation of the equivalence
principle.

</DOC>
<DOC>
<DOCNO> 170288 </DOCNO>
On the Problem of Programming Quantum Computers


  We study effects of the physical realization of quantum computers on their
logical operation. Through simulation of physical models of quantum computer
hardware, we analyse the difficulties that are encountered in programming
physical implementations of quantum computers. We discuss the origin of the
instabilities of quantum algorithms and explore physical mechanisms to enlarge
the region(s) of stable operation.

</DOC>
<DOC>
<DOCNO> 151168 </DOCNO>
Path Integral Approach to String Theory on AdS_3


  Using the path integral approach, we discuss the correlation functions of the
$SL(2,\bfC)/SU(2)$ WZW model, which corresponds to the string theory on the
Euclidean $AdS_3$. We obtain the two- and three-point functions for generic
primary fields in closed forms. By an appropriate change of the normalization
of the primary fields, our results coincide with those by Teschner, which were
obtained by using the bootstrap approach. The supergravity results are also
obtained in the semi-classical limit.

</DOC>
<DOC>
<DOCNO> 72303 </DOCNO>
de Sitter Brane Gravity: from Close-Up to Panorama


  We find explicitly the induced graviton propagator on de Sitter branes
embedded in various five-dimensional spacetimes; de Sitter branes in AdS and
Minkowski space are particular cases. By studying the structure of the
momentum-space propagator, we are able to extract interesting physics, much of
which is qualitatively different from that of flat branes. We find that 1)
there can be a set of graviton-like particles which mediate brane gravity at
different scales; 2) localized gravity can exist even on de Sitter branes in
Minkowski space; 3) Kaluza-Klein modes also contribute to conventional 4-D
gravity for de Sitter branes in AdS; and 4) Newton's constant can vary
considerably with scale. We comment on the implications for the effective
cosmological constant.

</DOC>
<DOC>
<DOCNO> 69721 </DOCNO>
A Brane World Model with Intersecting Branes


  A brane world model is investigated, in which there are many branes that may
intersect and self intersect. One of the branes, being a 3-brane, represents
our spacetime, while the other branes, if they intersect our brane world,
manifest themselves as matter in our 3-brane. It is shown that such a matter
encompasses dust of point particles and higher dimensional p-branes, and all
those objects follow "geodesics" in the world volume swept by our 3-brane. We
also point point out that such a model can be formulated in a background
independent way, and that the kinetic term for gravity arises from quantum
fluctuation of the brane.

</DOC>
<DOC>
<DOCNO> 100732 </DOCNO>
A new classification of links and some calculations using it


  A new classification theorem for links by the authors and Roger Fenn leads to
computable link invariants. As an illustration we distinguish the left and
right trefoils and recover the result of Carter et al that the 2-twist-spun
trefoil is not isotopic to its orientation reverse. We sketch the proof the
classification theorem. Full details will appear elsewhere

</DOC>
<DOC>
<DOCNO> 69449 </DOCNO>
Weak proton capture on 3He


  The astrophysical S-factor for the proton weak capture on 3He is calculated
with correlated-hyperspherical-harmonics bound and continuum wave functions
corresponding to realistic Hamiltonians consisting of the Argonne v14 or
Argonne v18 two-nucleon and Urbana-VIII or Urbana-IX three-nucleon
interactions. The nuclear weak charge and current operators have vector and
axial-vector components, that include one- and many-body terms. All possible
multipole transitions connecting any of the p 3He S- and P-wave channels to the
4He bound state are considered. The S-factor at a p 3He center-of-mass energy
of 10 keV, close to the Gamow-peak energy, is predicted to be 10.1 10^{-20} keV
b with the AV18/UIX Hamiltonian, a factor of about 4.5 larger than the value
adopted in the standard solar model. The P-wave transitions are found to be
important, contributing about 40 % of the calculated S-factor. The energy
dependence is rather weak: the AV18/UIX zero-energy S-factor is 9.64 10^{-20}
keV b, only 5 % smaller than the 10 keV result quoted above. The model
dependence is also found to be weak: the zero-energy S-factor is calculated to
be 10.2 10^{-20} keV b with the older AV14/UVIII model, only 6 % larger than
the AV18/UIX result. Our best estimate for the S-factor at 10 keV is therefore
(10.1 \pm 0.6) 10^{-20} keV b, when the theoretical uncertainty due to the
model dependence is included. This value for the calculated S-factor is not as
large as determined in fits to the Super-Kamiokande data in which the hep flux
normalization is free. However, the precise calculation of the S-factor and the
consequent absolute prediction for the hep neutrino flux will allow much
greater discrimination among proposed solar neutrino oscillation solutions.

</DOC>
<DOC>
<DOCNO> 68933 </DOCNO>
Renormalon Cancellation in Heavy Quarkonia and Determination of m_b, m_t


  This is an elementary introduction to the recent significant theoretical
progress in the field of heavy quarkonium physics. We show how renormalon
cancellation takes place in the heavy quarkonium system, such as bottomonium
and (remnant of) toponium resonance, and how this notion is useful in
extracting the MSbar masses of the bottom and top quarks.

</DOC>
<DOC>
<DOCNO> 99385 </DOCNO>
Algebra of differential forms with exterior differential $d^3=0$ in


  In this work, we construct the algebra of differential forms with the cube of
exterior differential equal to zero on one-dimensional space. We prove that
this algebra is a graded q-differential algebra where q is a cubic root of
unity. Since the square of differential is not equal to zero the algebra of
differential forms is generated not only by the first order differential but
also by the second order differential of a coordinate. We study the bimodule
generated by this second order differential, and show that its structure is
similar to the structure of bimodule generated by the first order differential
in the case of anyonic line.

</DOC>
<DOC>
<DOCNO> 13915 </DOCNO>
Interacting Fermi liquid in three dimensions at finite temperature: Part


  In this paper we complete the first step, namely the uniform bound on
completely convergent contributions, towards proving that a three dimensional
interacting system of Fermions is a Fermi liquid in the sense of Salmhofer. The
analysis relies on a direct space decomposition of the propagator, on a bosonic
multiscale cluster expansion and on the Hadamard inequality, rather than on a
Fermionic expansion and an angular analysis in momentum space, as was used in
the recent proof by two of us of Salmhofer's criterion in two dimensions.

</DOC>
<DOC>
<DOCNO> 40538 </DOCNO>
Kernel Estimation in High-Energy Physics


  Kernel Estimation provides an unbinned and non-parametric estimate of the
probability density function from which a set of data is drawn. In the first
section, after a brief discussion on parametric and non-parametric methods, the
theory of Kernel Estimation is developed for univariate and multivariate
settings. The second section discusses some of the applications of Kernel
Estimation to high-energy physics. The third section provides an overview of
the available univariate and multivariate packages. This paper concludes with a
discussion of the inherent advantages of kernel estimation techniques and
systematic errors associated with the estimation of parent distributions.

</DOC>
<DOC>
<DOCNO> 122227 </DOCNO>
Dynamical friction of bodies orbiting in a gaseous sphere


  The dynamical friction experienced by a body moving in a gaseous medium is
different from the friction in the case of a collisionless stellar system. Here
we consider the orbital evolution of a gravitational perturber inside a gaseous
sphere using three-dimensional simulations, ignoring however self-gravity. The
results are analysed in terms of a `local' formula with the associated Coulomb
logarithm taken as a free parameter. For forced circular orbits, the asymptotic
value of the component of the drag force in the direction of the velocity is a
slowly varying function of the Mach number in the range 1.0-1.6. The dynamical
friction timescale for free decay orbits is typically only half as long as in
the case of a collisionless background, which is in agreement with E.C.
Ostriker's recent analytic result. The orbital decay rate is rather insensitive
to the past history of the perturber. It is shown that, similar to the case of
stellar systems, orbits are not subject to any significant circularization.
However, the dynamical friction timescales are found to increase with
increasing orbital eccentricity for the Plummer model, whilst no strong
dependence on the initial eccentricity is found for the isothermal sphere.

</DOC>
<DOC>
<DOCNO> 119960 </DOCNO>
Kelvin-Helmholtz instability in three dimensional radiative jets


  The analysis of the stability properties of astrophysical jets against
Kelvin-Helmholtz (or shear-layer) instabilities plays a basic role in the
understanding the origin and physical characteristics of these objects.
Numerical simulations by Bodo et al. (1998) have shown that the
three-dimensional non-linear evolution of KH instabilities in supersonic jets
is substantially faster than in the two-dimensional case, leading to a cascade
of modes towards smaller scales and a very effective mixing and momentum
transfer to the ambient medium. On the other hand, Rossi et al. (1997) and
Micono et al. (1998) found, in two dimensions, that radiative losses tend to
reduce and delay mixing effects and momentum transfer to the ambient medium. In
this paper, as a logical next step, we investigate the effects of radiative
losses on the stability of 3D supersonic jets, assuming that the internal jet
density is initially lower, equal and higher than the ambient medium,
respectively. We find that light and equal-density radiative jets evolve in a
qualitatively similar fashion with respect to the corresponding adiabatic ones.
Conversely, we note substantial differences in the evolution of heavy jets:
they remain more collimated and do not spread out, while the momentum gained by
the ambient medium stays within ~ 5 jet radii.

</DOC>
<DOC>
<DOCNO> 101566 </DOCNO>
Random k-Surfaces


  The main result is the construction of ergodic transversal measures of full
support on the space of all k-surfaces of a compact hyperbolic 3-manifold. This
space is a laminated space, each of its leaf being identified with a "complete"
k-surface, i.e. a surface of constant (extrinsic) curvature k, where k belongs
to ]0,1[. Elsewhere, this space has been shown to have chaotic properties
mimicking those of the geodesic flow. This construction is achieved through a
coding of the space.

</DOC>
<DOC>
<DOCNO> 69767 </DOCNO>
Current Issues in Prompt Photon Production


  We give a brief account of recent theoretical developments in prompt photon
production.

</DOC>
<DOC>
<DOCNO> 70963 </DOCNO>
Effective Field Theory with Two and Three Nucleons


  Progress in the Effective Field Theory of two and three nucleon systems is
sketched, concentrating on the low energy version in which pions are integrated
out as explicit degrees of freedom. Examples given are calculations of deuteron
Compton scattering, three body forces and the triton, and nd partial waves.

</DOC>
<DOC>
<DOCNO> 11303 </DOCNO>
Experimental realization of a 2D fractional quantum spin liquid


  The ground-state ordering and dynamics of the two-dimensional (2D) S=1/2
frustrated Heisenberg antiferromagnet Cs_2CuCl_4 is explored using neutron
scattering in high magnetic fields. We find that the dynamic correlations show
a highly dispersive continuum of excited states, characteristic of the RVB
state, arising from pairs of S=1/2 spinons. Quantum renormalization factors for
the excitation energies (1.65) and incommensuration (0.56) are large.

</DOC>
<DOC>
<DOCNO> 118610 </DOCNO>
HI Bright Galaxies in the Southern Zone of Avoidance


  A blind survey for HI bright galaxies in the southern Zone of Avoidance, (212
deg < l < 36 deg; |b| < 5 deg), has been made with the 21 cm multibeam receiver
on the Parkes 64 m radiotelescope. The survey, sensitive to normal spiral
galaxies to a distance of about 40 Mpc and more nearby dwarfs, detected 110
galaxies. Of these, 67 have no counterparts in the NASA/IPAC Extragalactic
Database. In general, the uncataloged galaxies lie behind thicker obscuration
than do the cataloged objects. All of the newly-discovered galaxies have HI
flux integrals more than an order of magnitude lower than the Circinus galaxy.
The survey recovers the Puppis cluster and foreground group (Kraan-Korteweg &
Huchtmeier 1992), and the Local Void remains empty. The HI mass function
derived for the sample is satisfactorily fit by a Schechter function with
parameters alpha = 1.51 +- 0.12, Phi* = 0.006 +- 0.003, and log M* = 9.7 +-
0.10.

</DOC>
<DOC>
<DOCNO> 151592 </DOCNO>
Flux, Supersymmetry and M theory on 7-manifolds


  Various aspects of low energy M theory compactified to four dimensions are
considered. If the supersymmetry parameter is parallel in the unwarped metric,
then supersymmetry requires that the warp factor is trivial, the background
four-form field strength is zero and that the internal 7-manifold has $G_2$
holonomy (we assume the absence of boundaries and other impurities). A proposal
of Gukov - extended here to include M2-brane domain walls - for the
superpotential of the compactified theory is shown to yield the same result.
Finally, we make some speculative remarks concerning higher derivative
corrections and supersymmetry breaking.

</DOC>
<DOC>
<DOCNO> 178988 </DOCNO>
Chiral symmetry and meson exchange approach to hypernuclear decay


  We take an approach to the $\Lambda$ nonmesonic weak decay in nuclei based on
the exchange of mesons under the guidelines of chiral Lagrangians. The one pion
and one kaon exchange are considered, together with the exchange of two pions,
either correlated, leading to an important scalar-isoscalar exchange
($\sigma$-like exchange), or uncorrelated (box diagrams). A drastic reduction
of the OPE results for the $\Gamma_n/\Gamma_p$ ratio is obtained and the new
results are compatible with all present experiments within errors. The absolute
rates obtained for different nuclei are also in fair agreement with experiment.

</DOC>
<DOC>
<DOCNO> 71993 </DOCNO>
Hypernuclear potentials and the pseudoscalar meson exchange contribution


  The pieces of the hypernuclear strangeness violating potential due to the
pseudoscalar meson exchanges are derived using methods which were successfully
applied to hyperon nonleptonic decays. The estimates are tested by comparison
with measured hyperon nonleptonic decay amplitudes. All isospin changes $\Delta
I=1/2$ and $\Delta I=3/2$ are included in the derived potential. All
calculational methods used are reviewed and described in detail.

</DOC>
<DOC>
<DOCNO> 118138 </DOCNO>
Black hole X-ray binaries: A new view on soft-hard spectral transitions


  The theory of coronal evaporation predicts the formation of an inner hole in
the cool thin accretion disk for mass accretion rates below a certain value
(~ 1/50 of the Eddington mass accretion rate) and the sudden
disappearance of this hole when the mass accretion rate rises above that value.
The inner edge of the standard thin disk then suddenly shifts inward from about
a few hundred Schwarzschild radii to the last stable orbit. This appears to
quantitatively account for the observed transitions between hard and soft
spectral states at critical luminosities. Due to the evaporation process the
matter accreting in the geometrically thin disk changes to a hot coronal flow
which proceeds towards the black hole as an advection-dominated accretion flow
(ADAF; for a review see Narayan et al. 1998).

</DOC>
<DOC>
<DOCNO> 10836 </DOCNO>
Notes on Infinite Layer Quantum Hall Systems


  We study the fractional quantum Hall effect in three dimensional systems
consisting of infinitely many stacked two dimensional electron gases placed in
transverse magnetic fields. This limit introduces new features into the bulk
physics such as quasiparticles with non-trivial internal structure, irrational
braiding phases, and the necessity of a boundary hierarchy construction for
interlayer correlated states. The bulk states host a family of surface phases
obtained by hybridizing the edge states in each layer. We analyze the surface
conduction in these phases by means of sum rule and renormalization group
arguments and by explicit computations at weak tunneling in the presence of
disorder. We find that in cases where the interlayer electron tunneling is not
relevant in the clean limit, the surface phases are chiral semi-metals that
conduct only in the presence of disorder or at finite temperature. We show that
this class of problems which are naturally formulated as interacting bosonic
theories can be fermionized by a general technique that could prove useful in
the solution of such ``one and a half'' dimensional problems.

</DOC>
<DOC>
<DOCNO> 101303 </DOCNO>
The Donald-Flanigan problem for finite reflection groups


  The Donald--Flanigan problem for a finite group H and coefficient ring k asks
for a deformation of the group algebra kH to a separable algebra. It is solved
here for dihedral groups and for the classical Weyl groups (whose rational
group algebras are also computed), leaving but six finite reflection groups
with solutions unknown. We determine the structure of a wreath product of a
group with a sum of central separable algebras and show that if there is a
solution for H over k which is a sum of central separable algebras then there
is also a solution for the wreath product of H with any symmetric group,
abelian group, or dihedral group. The theorems suggested by the Donald-Flanigan
conjecture and subsequently proven follow, we also show, from a geometric
conjecture which although weaker for groups applies to a broader class of
algebras than group algebras.

</DOC>
<DOC>
<DOCNO> 9695 </DOCNO>
Structure determinations for random-tiling quasicrystals


  How, in principle, could one solve the atomic structure of a quasicrystal,
modeled as a random tiling decorated by atoms, and what techniques are
available to do it? One path is to solve the phase problem first, obtaining the
density in a higher dimensional space which yields the_averaged_ scattering
density in 3-dimensional space by the usual construction of an incommensurate
cut. A novel direct method for this is summarized and applied to an i(AlPdMn)
data set. This averaged density falls short of a true structure determination
(which would reveal the typical_unaveraged_ atomic patterns.) We discuss the
problematic validity of inferring an ideal structure by simply factoring out a
``perp-space'' Debye-Waller factor, and we test this using simulations of
rhombohedral tilings. A second, ``unified'' path is to relate the measured and
modeled intensities directly, by adjusting parameters in a simulation to
optimize the fit. This approach is well suited for unifying structural
information from diffraction and from minimizing total energies derived
ultimately from ab-initio calculations. Finally, we discuss the special
pitfalls of fitting random-tiling decagonal phases.

</DOC>
<DOC>
<DOCNO> 10430 </DOCNO>
Evolutionary minority game with heterogeneous strategy distribution


  We present detailed numerical results for a modified form of the so-called
Minority Game, which provides a simplified model of a competitive market. Each
agent has a limited set of strategies, and competes to be in a minority. An
evolutionary rule for strategy modification is included to mimic simple
learning. The results can be understood by considering crowd formation within
the population.

</DOC>
<DOC>
<DOCNO> 80677 </DOCNO>
Nonperturbative Gauge Fixing and Perturbation Theory


  We compare the gauge-fixing approach proposed by Jona-Lasinio and Parrinello,
and by Zwanziger (JPLZ) with the standard Fadeev-Popov procedure, and
demonstrate perturbative equality of gauge-invariant quantities, up to
irrelevant terms induced by the cutoff. We also show how a set of local,
renormalizable Feynman rules can be constructed for the JPLZ procedure.

</DOC>
<DOC>
<DOCNO> 67777 </DOCNO>
Spinodal Instabilities and the Dark Energy Problem


  The accelerated expansion of the Universe measured by high redshift Type Ia
Supernovae observations is explained using the non-equilibrium dynamics of
naturally soft boson fields. Spinodal instabilities inevitably present in such
systems yield a very attractive mechanism for arriving at the required equation
of state at late times, while satisfying all the known constraints on models of
quintessence.

</DOC>
<DOC>
<DOCNO> 178955 </DOCNO>
Hyperon effects on the properties of $\beta$-stable neutron star matter


  We present results from Brueckner-Hartree-Fock calculations for
$\beta$-stable neutron star matter with nucleonic and hyperonic degrees of
freedom employing the most recent parametrizations of the baryon-baryon
interaction of the Nijmegen group. Only $\Sigma^-$ and $\Lambda$ are present up
to densities $\sim 7\rho_0$. The corresponding equations of state are then used
to compute properties of neutron stars such as masses and radii.

</DOC>
<DOC>
<DOCNO> 69331 </DOCNO>
Quantum Field Theory at Finite Temperature: An Introduction


  In these notes we review some properties of Statistical Quantum Field Theory
at equilibrium, i.e Quantum Field Theory at finite temperature. We explain the
relation between finite temperature quantum field theory in (d,1) dimensions
and statistical classical field theory in d+1 dimensions. This identification
allows to analyze the finite temperature QFT in terms of the renormalization
group and the theory of finite size effects of the classical theory. We discuss
in particular the limit of high temperature (HT) or the situation of finite
temperature phase transitions. There the concept of dimensional reduction plays
an essential role. Dimensional reduction in some sense reflects the known
property that quantum effects are not important at high temperature. We
illustrate these ideas with several standard examples, phi^4 field theory, the
non-linear sigma model and the Gross-Neveu model, gauge theories. We construct
the corresponding effective reduced theories at one-loop order, using the
technique of mode expansion of fields in the imaginary time variable. In models
where the field is a vector with N components, the large N expansion provides
another specially convenient tool to study dimensional reduction.

</DOC>
<DOC>
<DOCNO> 8610 </DOCNO>
Effect of Magnetic field on the Pseudogap Phenomena in High-Tc Cuprates


  We theoretically investigate the effect of magnetic field on the pseudogap
phenomena in High-Tc cuprates.
 The obtained results well explain the experimental results including their
doping dependences.
 In our previous paper (J. Phys. Soc. Jpn. 68 (1999) 2999.), we have shown that
the pseudogap phenomena observed in High-Tc cuprates are naturally understood
as a precursor of the strong coupling superconductivity. On the other hand,
there is an interpretation for the recent high field NMR measurements to be an
evidence denying the pairing scenarios for the pseudogap. In this paper, we
investigate the magnetic field dependence of NMR $1/T_{1}T$ on the basis of our
formalism and show the interpretation to be inappropriate.
 The results indicate that the value of the characteristic magnetic field
$B_{{\rm ch}}$ is remarkably large in case of the strong coupling
superconductivity, especially near the pseudogap onset temperature $T^{*}$.
Therefore, the magnetic field dependences can not be observed and $T^{*}$ does
not vary when the strong pseudogap anomaly is observed. On the other hand,
$B_{{\rm ch}}$ is small in the comparatively weak coupling case and $T^{*}$
varies when the weak pseudogap phenomena are observed.
 These results properly explain the high magnetic field NMR experiments
continuously from under-doped to over-doped cuprates.
 Moreover, we discuss the transport phenomena in the pseudogap phase. The
behaviors of the in-plane resistivity, the Hall coefficient and the c-axis
resistivity in the pseudogap phase are naturally understood by considering the
d-wave pseudogap.

</DOC>
<DOC>
<DOCNO> 14071 </DOCNO>
Uniform semiclassical approximation in quantum statistical mechanics


  We present a simple method to deal with caustics in the semiclassical
approximation to the partition function of a one-dimensional quantum system.
The procedure, which makes use of complex trajectories, is applied to the
quartic double-well potential.

</DOC>
<DOC>
<DOCNO> 151836 </DOCNO>
Gauging of Geometric Actions and Integrable Hierarchies of KP Type


  This work consist of two interrelated parts. First, we derive massive
gauge-invariant generalizations of geometric actions on coadjoint orbits of
arbitrary (infinite-dimensional) groups $G$ with central extensions, with gauge
group $H$ being certain (infinite-dimensional) subgroup of $G$. We show that
there exist generalized ``zero-curvature'' representation of the pertinent
equations of motion on the coadjoint orbit. Second, in the special case of $G$
being Kac-Moody group the equations of motion of the underlying gauged WZNW
geometric action are identified as additional-symmetry flows of generalized
Drinfeld-Sokolov integrable hierarchies based on the loop algebra ${\hat \cG}$.
For ${\hat \cG} = {\hat {SL}}(M+R)$ the latter hiearchies are equivalent to a
class of constrained (reduced) KP hierarchies called ${\sl cKP}_{R,M}$, which
contain as special cases a series of well-known integrable systems (mKdV, AKNS,
Fordy-Kulish, Yajima-Oikawa etc.). We describe in some detail the loop algebras
of additional (non-isospectral) symmetries of ${\sl cKP}_{R,M}$ hierarchies.
Apart from gauged WZNW models, certain higher-dimensional nonlinear systems
such as Davey-Stewartson and $N$-wave resonant systems are also identified as
additional symmetry flows of ${\sl cKP}_{R,M}$ hierarchies. Along the way we
exhibit explicitly the interrelation between the Sato pseudo-differential
operator formulation and the algebraic (generalized) Drinfeld-Sokolov
formulation of ${\sl cKP}_{R,M}$ hierarchies. Also we present the explicit
derivation of the general Darboux-B\"acklund solutions of ${\sl cKP}_{R,M}$
preserving their additional (non-isospectral) symmetries, which for R=1 contain
among themselves solutions to the gauged $SL(M+1)/U(1)\times SL(M)$ WZNW field
equations.

</DOC>
<DOC>
<DOCNO> 99456 </DOCNO>
Roots of any Polynomial with Complex Integer Coefficients using


  The roots of any polynomial of degree m with complex integer coefficients can
be computed by manipulation of sequences made from distinct symbols and
counting the different symbols in the sequences. This method requires only
primitive operations like replacement of sequences and counting of symbols. No
calculations using advanced operations like multiplication, division,
logarithms etc. are needed. The method can be implemented as a geometric
construction using only a ruler and a compass.

</DOC>
<DOC>
<DOCNO> 117366 </DOCNO>
Evidence for a low-density Universe from the relative velocities of


  The motions of galaxies can be used to constrain the cosmological density
parameter Omega and the clustering amplitude of matter on large scales. The
mean relative velocity of galaxy pairs, estimated from the Mark III survey,
indicates that Omega = 0.35 +0.35/-0.25. If the clustering of galaxies is
unbiased on large scales, Omega = 0.35 +/- 0.15, so that an unbiased
Einstein-de Sitter model (Omega = 1) is inconsistent with the data.

</DOC>
<DOC>
<DOCNO> 40379 </DOCNO>
Measurements of Diffractive Vector-Meson Photoproduction at High


  We discuss recent preliminary results on the diffractive photoproduction of
{\rhoz}, $\phi$, and {\jpsi} mesons at high momentum transfer reported by the
ZEUS collaboration at HERA. A special-purpose calorimeter served to tag the
quasi-real photons ($\qsq<0.01 \gevsq$) in the process $\gamma + p \to {\rm
VM}+ Y$, where $Y$ represents a dissociated state of the proton. The resulting
range in photon-proton center-of-mass energy extends from 80 to 120 \gev. The
differential cross sections $\frac{\D\sigma}{\D t}$ were obtained in the region
${\abst}>1.2 \gevsq$, where $t$ denotes the squared momentum transfer to the
proton. The measurements provide good sensitivity to the observed power-law
dependence $\frac{\D\sigma}{\D t} \propto {(-t)}^{-n}$. Over the region in
momentum transfer covered by the data, the power is found to be approximately
$n\simeq 3$ for {\rhoz} and $\phi$ photoproduction, and approximately $n\simeq
2$ for {\jpsi} photoproduction.

</DOC>
<DOC>
<DOCNO> 101381 </DOCNO>
Fredholm Indices and the Phase Diagram of Quantum Hall Systems


  The quantized Hall conductance in a plateau is related to the index of a
Fredholm operator. In this paper we describe the generic ``phase diagram'' of
Fredholm indices associated with bounded and Toeplitz operators. We discuss the
possible relevance of our results to the phase diagram of disordered integer
quantum Hall systems.

</DOC>
<DOC>
<DOCNO> 40134 </DOCNO>
Reconstructing Supersymmetric Theories at High Energy Scales


  We have studied the reconstruction of supersymmetric theories at high scales
by evolving the fundamental parameters from the electroweak scale upwards.
Universal minimal supergravity and gauge mediated supersymmetry breaking have
been taken as representative alternatives. Pseudo-fixed point structures
require the low-energy boundary values to be measured with high precision.

</DOC>
<DOC>
<DOCNO> 100930 </DOCNO>
Spin Geometry on Quantum Groups via Covariant Differential Calculi


  Let A be a cosemisimple Hopf *-algebra with antipode S and let $\Gamma$ be a
left-covariant first order differential *-calculus over A such that $\Gamma$ is
self-dual and invariant under the Hopf algebra automorphism S^2. A quantum
Clifford algebra $\Cl(\Gamma,\sigma,g)$ is introduced which acts on Woronowicz'
external algebra $\Gamma^\wedge$. A minimal left ideal of
$\Cl(\Gamma,\sigma,g)$ which is an A-bimodule is called a spinor module.
Metrics on spinor modules are investigated. The usual notion of a linear left
connection on $\Gamma$ is extended to quantum Clifford algebras and also to
spinor modules. The corresponding Dirac operator and connection Laplacian are
defined. For the quantum group SL_q(2) and its bicovariant $4D_\pm$-calculi
these concepts are studied in detail. A generalization of Bochner's theorem is
given. All invariant differential operators over a given spinor module are
determined. The eigenvalues of the Dirac operator are computed.
 Keywords: quantum groups, covariant differential calculus, spin geometry

</DOC>
<DOC>
<DOCNO> 69792 </DOCNO>
Preliminary results and perspectives in the Archeops experiment


  Observations of the Cosmic Microwave Background (CMB) temperature
fluctuations are a powerful tool for testing theories of the early Universe and
for measuring cosmological parameters. We present basics of CMB physics, review
some of the most recent results and discuss their implications for cosmology.
The Archeops balloon-borne experiment is designed to map the CMB with an
angular resolution of 10 arcminutes and a precision of 30 $\mu\mathrm{K}$ per
pixel. This will allow the measurement of the CMB fluctuation power spectrum
from large to small angular scales. We describe preliminary results from the
test flight which took place in July 1999 and present perspectives for upcoming
scientific flights (January 2001).

</DOC>
<DOC>
<DOCNO> 102263 </DOCNO>
The classification of exceptional Dehn surgeries on 2-bridge knots


  We will classify all exceptional Dehn surgeries on 2-bridge knots according
to whether they produce reducible, toroidal, or small Seifert fibered
manifolds.

</DOC>
<DOC>
<DOCNO> 72304 </DOCNO>
Q-ball Evolution, B-ball Baryogenesis and the f_{B} Problem


  We consider some of the issues surrounding the formation and evolution of
Q-balls in the MSSM and its extensions. The ratio of the baryon number packed
into Q-balls to that outside, f_{B}, plays a fundamental role in determining
the relationship of dark matter to the baryon number in the Universe at
present. The final value of f_{B} will depend upon the details of the formation
of Q-balls from the collapse of the Affleck-Dine condensate and upon the
subsequent evolution of the ensemble of Q-balls. We discuss the implications
for neutralino dark matter in the gravity-mediated scenario and show that a
light neutralino is necessary in most cases to account for the baryon to dark
matter ratio, with an NMSSM singlino LSP of mass m_{\chi} \lae 20 \GeV being a
favoured candidate.

</DOC>
<DOC>
<DOCNO> 121346 </DOCNO>
Parsec-Scale Imaging of HI Absorption in 1946+708


  In the last several years, a number of compact extragalactic radio sources
have been found to exhibit neutral hydrogen absorption at or near the systemic
velocities of their host galaxies. Models proposed to explain this phenomenon
involve a circumnuclear torus of gas and dust. The orientation of this
structure determines whether or not the central engine appears obscured.
Understanding the spatial distribution and kinematics of the HI detected toward
the central parsecs of these sources provides an important test of this model
and of unified schemes for AGN.
  We present results of Global VLBI Network observations of the redshifted 21
cm HI line toward the Compact Symmetric Object 1946+708 (z=0.101). This source
is of particular interest because it exhibits bi-directional motion measurable
on timescales of a few years. The resulting unique information about the
geometry of the continuum source greatly assists in the interpretation of the
HI distribution. We find significant structure in the gas on parsec scales. The
peak column density of the HI occurs near the center of activity of the source,
as does the highest velocity dispersion (FWHM ~ 350 to 400 km/s). The
distribution of gas in 1946+708 is strongly suggestive of a circumnuclear torus
of atomic material with one or more additional compact clumps of gas along the
line of sight to the approaching jet.

</DOC>
<DOC>
<DOCNO> 102810 </DOCNO>
On twisted representations of vertex algebras


  In this paper we develop a formalism for working with twisted realizations of
vertex and conformal algebras. As an example, we study realizations of
conformal algebras by twisted formal power series. The main application of our
technique is the construction of a very large family of representations for the
vertex superalgebra $\goth V_\Lambda$ corresponding to an integer lattice
$\Lambda$. For an automorphism $\^\sigma:\goth V_\Lambda\to\goth V_\Lambda$
coming from a finite order automorphism $\sigma:\Lambda \to \Lambda$ we define
a category $\cal O_{\^\sigma}$ of twisted representations of $\goth V_\Lambda$
and show that this category is semisimple with finitely many isomorphism
classes of simple objects.

</DOC>
<DOC>
<DOCNO> 151493 </DOCNO>
Two-dimensional fractional supersymmetric conformal- and logarithmic


  A general two-dimensional fractional supersymmetric conformal field theory is
investigated. The structure of the symmetries of the theory is studied.
Applying the generators of the closed subalgebra generated by
$(L_{-1},L_{0},G_{-1/(F+1)})$ and
$(\bar{L}_{-1},\bar{L}_{0},\bar{G}_{-1/(F+1)})$, the two point functions of the
component-fields of supermultiplets are calculated. Then the logarithmic
superconformal field theories are investigated and the chiral and full
two-point functions are obtained.

</DOC>
<DOC>
<DOCNO> 11773 </DOCNO>
Crossover phenomenon in self-organized critical sandpile models


  We consider a stochastic sandpile where the sand-grains of unstable sites are
randomly distributed to the nearest neighbors. Increasing the value of the
threshold condition the stochastic character of the distribution is lost and a
crossover to the scaling behavior of a different sandpile model takes place
where the sand-grains are equally transferred to the nearest neighbors. The
crossover behavior is numerically analyzed in detail, especially we consider
the exponents which determine the scaling behavior.

</DOC>
<DOC>
<DOCNO> 69779 </DOCNO>
Living Inside a Hedgehog: Higher-dimensional Solutions that Localize


  We consider spherically symmetric higher-dimensional solutions of Einstein's
equations with a bulk cosmological constant and n transverse dimensions. In
contrast to the case of one or two extra dimensions we find no solutions that
localize gravity when $n\geq 3$, for strictly local topological defects. We
discuss global topological defects that lead to the localization of gravity and
estimate the corrections to Newton's law. We show that the introduction of a
bulk ``hedgehog'' magnetic field leads to a regular geometry and localizes
gravity on the 3-brane with either a positive, zero or negative bulk
cosmological constant. The corrections to Newton's law on the 3-brane are
parametrically the same as for the case of one transverse dimension.

</DOC>
<DOC>
<DOCNO> 102328 </DOCNO>
On The Geometric Monodromy Of The Milnor Fibre


  In this paper we show that the geometric monodromy $\phi$ of the Milnor
fibre, has finite order q if and only if the operator $\phi^q_*$ acts trivially
on the homology. The proof is based on the classical methods of surgery.

</DOC>
<DOC>
<DOCNO> 8920 </DOCNO>
Wavefronts may move upstream in doped semiconductor superlattices


  In weakly coupled, current biased, doped semiconductor superlattices, domain
walls may move upstream against the flow of electrons. For appropriate doping
values, a domain wall separating two electric field domains moves downstream
below a first critical current, it remains stationary between this value and a
second critical current, and it moves upstream above. These conclusions are
reached by using a comparison principle to analyze a discrete drift-diffusion
model, and validated by numerical simulations. Possible experimental
realizations are suggested.

</DOC>
<DOC>
<DOCNO> 67677 </DOCNO>
Effects of CP-Violation in Neutralino Scattering and Annihilation


  We summarize our paper hep-ph/9908390, where we find that in some regions of
supersymmetric parameter space, CP violating effects that mix the CP-even and
CP-odd Higgs bosons can enhance the neutralino annihilation rate by factors of
10^6, and reduce the neutralino scattering rate off nucleons by factors of
10^{-7}.

</DOC>
<DOC>
<DOCNO> 119455 </DOCNO>
Redshifts of 10 quasar candidates in the field of the rich absorption


  We have obtained low resolution (~20 Angstrom FWHM) slit spectra of 10 quasar
candidates located within one degree of the z = 2.181 quasar Q0122-380 with the
objective of searching for signs of large scale structure matching the
intervening rich absorption complexes seen over the redshift range 1.81<z<1.97
toward this object. Of the 8 confirmed quasars, 4 turn out to have redshifts z
< 1.8, placing them well in front of the redshift range of interest. Two of the
three confirmed quasars at redshift z > 1.8 show no obvious absorption matching
that of Q0122-380 at our spectral resolution and signal-to-noise ratio. The
third object at a redshift of z = 1.868 displays strong z_{abs} \sim z_{em}
absorption systems at z = 1.84 and z = 1.86 and a possibly BAL-like trough at z
= 1.76. If not intrinsic in nature, the former two systems could potentially be
related to the absorption seen in Q0122-380, albeit over a distance of 50.2
arcmin (D_\perp \simeq 15 h^{-1} Mpc at z = 1.9).

</DOC>
<DOC>
<DOCNO> 178455 </DOCNO>
Modeling J/psi Properties at Finite Temperature


  We model J/psi using an effective lagrangian approach and calculate its
spectral function in a gas of light mesons at finite temperature. We explore
the hadronic landscape estimating cross sections for elastic and inelastic
channels. Effects of form factors are tested in a general, but consistently
gauge invariant manner. Relevance to heavy ion experiments is discussed.

</DOC>
<DOC>
<DOCNO> 151145 </DOCNO>
On the nature of fermion-monopole supersymmetry


  It is shown that the generator of the nonstandard fermion-monopole
supersymmetry uncovered by De Jonghe, Macfarlane, Peeters and van Holten, and
the generator of its standard N=1/2 supersymmetry have to be supplemented by
their product operator to be treated as independent supercharge. As a result,
the fermion-monopole system possesses the nonlinear N=3/2 supersymmetry having
the nature of the 3D spin-1/2 free particle's supersymmetry generated by the
supercharges represented in a scalar form. Analyzing the supercharges'
structure, we trace how under reduction of the fermion-monopole system to the
spherical geometry the nonlinear N=3/2 superalgebra comprising the Hamiltonian
and the total angular momentum as even generators is transformed into the
standard linear N=1 superalgebra with the Hamiltonian to be the unique even
generator.

</DOC>
<DOC>
<DOCNO> 119717 </DOCNO>
On the Thermal Instability in a Contracting Gas Cloud and Formation of a


  We perform linear analysis of thermal instability in a contracting large
cloud filled with warm HI gas and investigate the effect of metallicity and
radiation flux. When the cloud reaches critical density n_f, the cloud
fragments into cool, dense condensations because of thermal instability. For a
lower metallicity gas cloud, the value of n_f is high. Collision between
condensations will produce self-gravitating clumps and stars thereafter. From
the result of calculation, we suggest that high star formation efficiency and
bound cluster formation are realized in low-metallicity and/or strong-radiation
environments.

</DOC>
<DOC>
<DOCNO> 120128 </DOCNO>
Pair Creation at Shocks: Application to Agns


  We investigate the effect of pair creation on a shock structure. Actually,
particles accelerated by a shock can be sufficiently energetic to boost, via
Inverse Compton process for example, surrounding soft photons above the rest
mass electron energy and thus to trigger the pair creation process. The
increase of the associated pair pressure is thus able to disrupt the plasma
flow and possibly, for too high pressure, to smooth it completely. Reversely,
significant changes of the flow velocity profile may modify the distribution
function of the accelerated particles in such a way that the number of
particles enable to trigger the pair creation process may change, modifying
consequently the pair creation rate. We propose here, using simplifying
assumptions, to study the global behavior of a shock structure in an
environment dominated by pairs.

</DOC>
<DOC>
<DOCNO> 118102 </DOCNO>
An extended multi-zone model for the MCG-6-30-15 warm absorber


  The variable warm absorber seen with {\em ASCA} in the X-ray spectrum of
MCG$-$6-30-15 shows complex time behaviour in which the optical depth of OVIII
anticorrelates with the flux whereas that of OVII is unchanging. The
explanation in terms of a two zone absorber has since been challenged by {\em
BeppoSAX} observations. These present a more complicated behaviour for the
OVIII edge. We demonstrate here that the presence of a third, intermediate,
zone can explain all the observations. In practice, warm absorbers are likely
to be extended, multi-zone regions of which only part causes directly
observable absorption edges at any given time.

</DOC>
<DOC>
<DOCNO> 14126 </DOCNO>
Theory of 2D metal-insulator transition I: Zero Magnetic field


  We propose a scaling theory of 2D metal insulator transition discovered by
Kravchenko and coworkers. In this theory conductance/resistance duality is an
exact relation. The exponent of the stretched exponential in $\sigma(T)$ is
determined by the temperature dependence of the coherence length. The
quantum-chaotic nature of the transition is manifested in the square form of
the phenomenological scaling function.

</DOC>
<DOC>
<DOCNO> 121002 </DOCNO>
Interstellar X-ray Absorption Spectroscopy of Oxygen, Neon, and Iron


  We find resolved interstellar O K, Ne K, and Fe L absorption spectra in the
Chandra Low Energy Transmission Grating Spectrometer spectrum of the low mass
X-ray binary X0614+091. We measure the column densities in O and Ne, and find
direct spectroscopic constraints on the chemical state of the interstellar O.
These measurements probably probe a low-density line of sight through the
Galaxy and we discuss the results in the context of our knowledge of the
properties of interstellar matter in regions between the spiral arms.

</DOC>
<DOC>
<DOCNO> 10359 </DOCNO>
Spin bath-mediated decoherence in superconductors


  We consider a SQUID tunneling between 2 nearly degenerate flux states.
Decoherence caused by paramagnetic and nuclear spins in the low-$T$ limit is
shown to be much stronger than that from electronic excitations. The
decoherence time $\tau_{\phi}$ is determined by the linewidth $E_o$ of spin
bath states, which can be reduced by a correct choice of ring geometry and
isotopic purification. $E_o$ can be measured in either field sweep or microwave
absorption experiments, allowing both a test of the theory and design control.

</DOC>
<DOC>
<DOCNO> 170697 </DOCNO>
Entangled Quantum Clocks for Measuring Proper-Time Difference


  We report that entangled pairs of quantum clocks (non-degenerate quantum
bits) can be used as a specialized detector for precisely measuring difference
of proper-times that each constituent quantum clock experiences. We describe
why the proposed scheme would be more precise in the measurement of proper-time
difference than a scheme of two-separate-quantum-clocks. We consider
possibilities that the proposed scheme can be used in precision test of the
relativity theory.

</DOC>
<DOC>
<DOCNO> 102702 </DOCNO>
Nonequivalent Statistical Equilibrium Ensembles and Refined Stability


  Statistical equilibrium models of coherent structures in two-dimensional and
barotropic quasi-geostrophic turbulence are formulated using canonical and
microcanonical ensembles, and the equivalence or nonequivalence of ensembles is
investigated for these models. The main results show that models in which the
global invariants are treated microcanonically give richer families of
equilibria than models in which they are treated canonically. Such global
invariants are those conserved quantities for ideal dynamics which depend on
the large scales of the motion; they include the total energy and circulation.
For each model a variational principle that characterizes its equilibrium
states is derived by invoking large deviations techniques to evaluate the
continuum limit of the probabilistic lattice model. An analysis of the two
different variational principles resulting from the canonical and
microcanonical ensembles reveals that their equilibrium states coincide only
when the microcanonical entropy function is concave. These variational
principles also furnish Lyapunov functionals from which the nonlinear stability
of the mean flows can be deduced. While in the canonical model the well-known
Arnold stability theorems are reproduced, in the microcanonical model more
refined theorems are obtained which extend known stability criteria when the
microcanonical and canonical ensembles are not equivalent. A numerical example
pertaining to geostrophic turbulence over topography in a zonal channel is
included to illustrate the general results.

</DOC>
<DOC>
<DOCNO> 40253 </DOCNO>
On the Quark and Gluon Substructure of the Sigma and other Scalar Mesons


  Within the increasing experimental evidence of the existence of the I=0
scalar low mass and wide \sigma meson, we review the {\it first} analysis of
its quark and gluon substructure from QCD spectral sum rules and some
low-energy theorems. The present data favour equal components of \bar uu+ \bar
dd and of gg in its wave function, which make the wide sigma and the narrow
f_0(980) as \eta'-like particles. A coherent picture of the other I=0 scalar
mesons spectra within this mixing scheme is shortly discussed. We also expect
the a_0(980) to be the lowest isovector \bar ud state, and the K^*_0(1430) its
\bar ds partner.

</DOC>
<DOC>
<DOCNO> 12046 </DOCNO>
Cluster Property and Robustness of Ground States of Interacting Many


  We study spatial correlation functions of local operators of interacting many
bosons confined in a box of a large, but volume V, for various `ground states'
whose energy densities are almost degenerate. The ground states include the
coherent state of interacting bosons (CSIB), the number state of interacting
bosons (NSIB), and the number-phase squeezed state of interacting bosons, which
interpolates between the CSIB and NSIB. It was shown previously that only the
CSIB is robust (i.e., does not decohere for a macroscopically long time)
against the leakage of bosons into an environment. We show that for the CSIB
the spatial correlation of any local operators A(r) and B(r') (which are
localized around r and r', respectively) vanishes as |r - r' | \sim V^{1/3} \to
\infty, i.e., the CSIB has the `cluster property.' In contrast, the other
ground states do not possess the cluster property. Therefore, we have
successfully shown that the robust state has the cluster property. This ensures
the consistency of the field theory of bosons with macroscopic theories.

</DOC>
<DOC>
<DOCNO> 80973 </DOCNO>
The unquenched Upsilon spectrum


  We describe the bottomonium spectrum obtained on the UKQCD dynamical
ensembles and its comparison to quenched results. We include a determination of
alpha_s and m_b from the dynmaical results.

</DOC>
<DOC>
<DOCNO> 151195 </DOCNO>
Hurwitz theorem and parallelizable spheres from tensor analysis


  By using tensor analysis, we find a connection between normed algebras and
the parallelizability of the spheres S$^1$, S$^3$ and S$^7.$ In this process,
we discovered the analogue of Hurwitz theorem for curved spaces and a
geometrical unified formalism for the metric and the torsion. In order to
achieve these goals we first develope a proof of Hurwitz theorem based in
tensor analysis. It turns out that in contrast to the doubling procedure and
Clifford algebra mechanism, our proof is entirely based in tensor algebra
applied to the normed algebra condition. From the tersor analysis point of view
our proof is straightforward and short. We also discuss a possible connection
between our formalism and the Cayley-Dickson algebras and Hopf maps.

</DOC>
<DOC>
<DOCNO> 84222 </DOCNO>
Rotational modes of non-isentropic stars and the gravitational radiation


  We investigate the properties of r-mode and inertial mode of slowly rotating,
non-isentropic, Newtonian stars, by taking account of the effects of the
Coriolis force and the centrifugal force. For the non-isentropic models we
consider only two cases, that is, the models with the stable fluid
stratification in the whole interior and the models that are fully convective.
For simplicity we call these two kinds of models "radiative" and "convective"
models in this paper. For both cases, we assume the deviation of the models
from isentropic structure is small. Examining the dissipation timescales due to
the gravitational radiation and several viscous processes for the polytropic
neutron star models, we find that the gravitational radiation driven
instability of the r-modes remains strong even in the non-isentropic models.
Calculating the rotational modes of the radiative models as functions of the
angular rotation frequency $\Omega$, we find that the inertial modes are
strongly modified by the buoyant force at small $\Omega$, where the buoyant
force as a dominant restoring force becomes comparable with or stronger than
the Coriolis force. Because of this property we obtain the mode sequences in
which the inertial modes at large $\Omega$ are identified as g-modes or the
r-modes with l=|m| at small $\Omega$. We also note that as $\Omega$ increases
from $\Omega=0$ the retrograde g-modes become retrograde inertial modes, which
are unstable against the gravitational radiation reaction.

</DOC>
<DOC>
<DOCNO> 169751 </DOCNO>
Parallel and Anti-Parallel Spins: More Differences


  The authors have withdrawn this paper.

</DOC>
<DOC>
<DOCNO> 67954 </DOCNO>
Role of negative-energy states and Breit interaction in calculation of


  It is demonstrated that Breit and negative-energy state contributions reduce
the 2.5 sigma deviation [S.C. Bennett and C.E. Wieman, Phys. Rev. Lett. 82,
2484 (1999)] in the value of the weak charge of 133Cs from the Standard Model
prediction to 1.7sigma. The corrections are obtained in the relativistic
many-body perturbation theory by combining all-order Coulomb and second-order
Breit contributions. The corrections to parity-nonconserving amplitudes amount
to 0.6% in 133Cs and 1.1% in 223Fr. The relevant magnetic-dipole hyperfine
structure constants are modified at the level of 0.3% in Cs, and 0.6% in Fr.
Electric-dipole matrix elements are affected at 0.1% level in Cs and a few 0.1%
in Fr.

</DOC>
<DOC>
<DOCNO> 116899 </DOCNO>
Beam Dynamics Studies for a High Current Ion Injector


  Recent ion source developments resulted in the generation of high brilliance,
high current beams of protons and light ions. After extraction and transport
the beams with large internal space charge forces have to be captured, bunched
and preaccelerated for the injection into the following driver part of a new
generation of high intensity beam facilities for neutron sources, energy
production, transmutation e.g. A combination of RFQ and DTL is considered to be
a good solution for such a high current ion injector. Some preliminary beam
dynamics layouts have been investigated by multiparticle simulations. Basic
parameters like frequency, ion energy and sparking have been varied for the
International Fusion Material Irradiation Facility (IFMIF) scenario as an
example. The main interest was directed to high transmission, low losses and
emittance conservation. The beam matching to the RFQ is shortly discussed as
well as the matching between RFQ and DTL.

</DOC>
<DOC>
<DOCNO> 151930 </DOCNO>
Dynamical Localization of Gravity


  We show that the thin wall limit of the thick domain wall associated with a
sine-Gordon soliton in a single non-compactified patch of 5-dimensional
spacetime explicitly yields the Randall-Sundrum localized gravity two patch
brane, with its discrete $Z_2$ symmetry arising from the discrete symmetry of
the potential, and with the thin Minkowski brane
$\Lambda_5+\kappa^2_5\Lambda^2_b/6=0$ relation between bulk and brane
cosmological constants arising naturally without any need for fine tuning.
Additionally we show that for an embedded thin de Sitter brane, localization of
gravity is again possible provided the 5-space is compactified, with the now
non-zero net cosmological constant $\Lambda_5+\kappa^2_5\Lambda^2_b/6$ on the
brane being found to vary inversely with the compactification radius.

</DOC>
<DOC>
<DOCNO> 83411 </DOCNO>
If P \neq NP then Some Strongly Noninvertible Functions are Invertible


  Rabi, Rivest, and Sherman alter the standard notion of noninvertibility to a
new notion they call strong noninvertibility, and show -- via explicit
cryptographic protocols for secret-key agreement ([RS93,RS97] attribute this to
Rivest and Sherman) and digital signatures [RS93,RS97] -- that strongly
noninvertible functions would be very useful components in protocol design.
Their definition of strong noninvertibility has a small twist (``respecting the
argument given'') that is needed to ensure cryptographic usefulness. In this
paper, we show that this small twist has a large, unexpected consequence:
Unless P=NP, some strongly noninvertible functions are invertible.

</DOC>
<DOC>
<DOCNO> 70438 </DOCNO>
The many sources effect on the genuine multihadron correlations


  Here we report on a study aimed to explore the dependence of the genuine
multiparticle correlations on the number of sources while the influence of
other possible factors affecting the multihadron production is avoided. The
analysis utilised the normalised cumulants, calculated in three-dimensional
phase space, of the reaction e+e- -> Z -> hadrons using a large Monte Carlo
event sample. The multi-sources reactions were simulated by overlaying a few
independent single e+e- annihilation events. It was found that as the number of
sources S increases, the cumulants do not change significantly their structure,
but those of an order q>2 (i.e. more than 2 pions) decrease fast in their
magnitude. This reduction can be understood in termsof combinatorial
considerations of source mixing which dilutes the correlations by a factor of
about 1/S^{q-1} which can also serve as a method to estimated the number of
sources. This expected suppression is well reproduced by recent cumulant
measurements in hadron and nucleus induced reactions both in one (rapidity) and
two (rapidity vs. azimuthal angle) dimensions. The diminishing genuine
correlations effect should also appear in other dynamical correlations like the
Bose-Einstein in e+e- -> W+W- -> hadrons and in nucleus-nucleus reactions.

</DOC>
<DOC>
<DOCNO> 178505 </DOCNO>
Projectile structure effects in the Coulomb breakup of one-neutron halo


  We investigate the Coulomb breakup of neutron rich nuclei 11Be and
(19,17,15)C within a theory developed in the framework of Distorted Wave Born
Approximation. Finite range effects are included by a local momentum
approximation, which allows incorporation of realistic wave functions for these
nuclei in our calculations. Energy and angular as well as parallel momentum
distributions of the fragments emitted in the breakup of these nuclei on heavy
targets have been calculated using several structure models for their ground
state. Comparison with the available experimental data shows that the results
are selective about the ground state wave function of the projectile. Our
investigations confirm that the nuclei 11Be, 19C and 15C have a one-neutron
halo structure in their ground states. However, for 17C such a structure
appears to be less likely. Calculations performed within our method have also
been compared with those from an adiabatic model and the results are discussed.

</DOC>
<DOC>
<DOCNO> 151280 </DOCNO>
Non-Abelian (2,0)-Super-Yang-Mills Coupled to Nonlinear Sigma-Models


  Following a previous work on Abelian (2,0)-gauge theories, one reassesses
here the task of coupling (2,0) relaxed Yang-Mills super-potentials to a
(2,0)-nonlinear Sigma-model, by gauging the isotropy or the isometry group of
the latter. One pays special attention to the extra "chiral-like"
component-field gauge potential that comes out from the relaxation of
constraints.

</DOC>
<DOC>
<DOCNO> 122872 </DOCNO>
Terapixel Surveys for Cosmic Shear


  The recent detections of cosmic shear signal announced by several groups have
demonstrated the feasibility of this challenging program and convinced astro-
nomers of its potential for cosmology. Cosmic shear analysis demands to handle
Gigabytes of data in order to probe several square degrees in subarcsecond deep
imaging mode. The success of these surveys is sensitive to the designs of the
observation strategy, the organization of the data reduction pipelines and the
links of the data base with surveys like X-ray or spectroscopic follow up. We
describe the cosmic shear surveys we have carried out at the VLT and at CFHT
and the way we handle this huge data set in a more general context including
the VIRMOS and the XMM-LSS surveys, and the future CMB surveys.

</DOC>
<DOC>
<DOCNO> 13409 </DOCNO>
Noise in refrigerating tunnel junctions and in microbolometers


  Microrefrigerators based on normal metal-insulator-superconductor (NIS)
junctions represent a very attractive alternative to cool the microbolometers
and calorimeters for astrophysical observations in space-borne experiments. The
performance in such measurements requires a good knowledge of the noise sources
in the detectors. In this paper we present detailed calculations of the thermal
fluctuations and of the noise equivalent power due to the heat transfer through
the NIS junctions or due to the thermal contact between different subsystems of
the detector. The influence of the background radiation will also be evaluated.
Analytical approximations, valid at low temperatures, are given.

</DOC>
<DOC>
<DOCNO> 101924 </DOCNO>
Two-dimensional algebro-geometric difference operators


  A generalized inverse problem for a two-dimensional difference operator is
introduced. A new construction of the algebro-geometric difference operators of
two types first considered by I.M.Krichever and S.P.Novikov is proposed

</DOC>
<DOC>
<DOCNO> 8190 </DOCNO>
The exotic Galilei group and the "Peierls substitution"


  Taking advantage of the two-parameter central extension of the planar Galilei
group, we construct a non relativistic particle model in the plane. Owing to
the extra structure, the coordinates do not commute. Our model can be viewed as
the non-relativistic counterpart of the relativistic anyon considered before by
Jackiw and Nair. For a particle moving in a magnetic field perpendicular to the
plane, the two parameters combine with the magnetic field to provide an
effective mass. For vanishing effective mass the phase space admits a
two-dimensional reduction, which represents the condensation to collective
``Hall'' motions and justifies the rule called ``Peierls substitution''.
Quantization yields the wave functions proposed by Laughlin to describe the
Fractional Quantum Hall Effect.

</DOC>
<DOC>
<DOCNO> 80778 </DOCNO>
QCD with a theta-vacuum term: a complex system with a simple complex


  We reanalyze in the first part of this paper the old question of P and CT
realization in QCD. The second part is devoted to establish general results on
the phase structure of this model in the presence of a $\theta$-vacuum term.

</DOC>
<DOC>
<DOCNO> 10176 </DOCNO>
Wigner crystallization in the two electron quantum dot


  Wigner crystallization can be induced in a quantum dot by increasing the
effective electron-electron interaction through a decrease of the electron
density or by the application of a strong magnetic field. We show that the
ground state in both cases is very similar but the energy scales are very
different and therefore also the dynamics.

</DOC>
<DOC>
<DOCNO> 69014 </DOCNO>
Phenomenology of Neutrino Oscillations


  The phenomenology of solar, atmospheric, supernova and laboratory neutrino
oscillations is described. Analytical formulae for matter effects are reviewed.
The results from oscillations are confronted with neutrinoless double beta
decay.

</DOC>
<DOC>
<DOCNO> 11128 </DOCNO>
Charge and spin addition energies of one dimensional quantumn dot


  We derive the effective action for a one dimensional electron island formed
between a double barrier in a single channel quantum wire including the
electron spin. Current and energy addition terms corresponding to charge and
spin are identified. The influence of the range and the strength of the
electron interaction and other system parameters on the charge and spin
addition energies, and on the excitation spectra of the modes confined within
the island is studied. We find by comparison with experiment that spin
excitations in addition to non-zero range of the interaction and inhomogeneity
effects are important for understanding the electron transport through one
dimensional quantum islands in cleaved-edge-overgrowth systems.

</DOC>
<DOC>
<DOCNO> 69804 </DOCNO>
On the Determination of Nonleptonic Kaon Decays from $K\to\pi$ Matrix


  The coupling constants of the order $p^2$ low-energy weak effective
lagrangian can be determined from the $K\to\pi$ and $K\to 0$ weak matrix
elements, choosing degenerate quark masses for the first of these. However, for
typical values of quark masses in Lattice QCD computations, next-to-leading
$O(p^4)$ corrections are too large to be ignored, and will need to be included
in future analyses. Here we provide the complete $O(p^4)$ expressions for these
matrix elements obtained from Chiral Perturbation Theory, valid for partially
quenched QCD with $N$ degenerate sea quarks. Quenched QCD corresponds to the
special case N=0. We also discuss the role of the $\eta'$ meson in some detail,
and we give numerical examples of the size of chiral logarithms.

</DOC>
<DOC>
<DOCNO> 169639 </DOCNO>
Actual computational time-cost of the Quantum Fourier Transform in a


  We found that the actual computational time-cost of the QFT is O(n 2^n) for
large n in a quantum computer using nuclear spins. The computational cost of a
quantum algorithm has usually been estimated as the sum of the universal gates
required in such ideal mathematical models as the Quantum Turing Machine(QTM)
and the quantum circuit. This cost is proportional to an actual time-cost in
the physical implementation where all quantum operations can be achieved in the
same time. However, if the implementation takes a different time for each
quantum gate, there is a possibility that the actual time-cost will have a
different behavior from the ideal cost. So we estimated the actual time-cost of
the QFT in these implementations by considering the gating time. The actual
time-cost is drastically different from O(n^2) estimated by complexity
analysis.

</DOC>
<DOC>
<DOCNO> 9773 </DOCNO>
Phase field under stress


  A phase-field approach describing the dynamics of a strained solid in contact
with its melt is developed. By rigorous asymptotic analysis we show that the
sharp-interface limit of this model recovers the continuum model equations for
the Grinfeld instability. Moreover, we use our approach to derive hitherto
unknown sharp-interface equations for a situation including a field of body
forces. The numerical utility of the phase-field approach is demonstrated by
comparison with a sharp-interface simulation. We then investigate the dynamics
of extended systems within the phase-field model which contains an inherent
lower length cutoff, thus avoiding cusp singularities. It is found that a
periodic array of grooves generically evolves into a superstructure which
arises from a series of imperfect period doublings. For wavenumbers close to
the fastest-growing mode of the linear instability, the first period doubling
can be obtained analytically. Both the dynamics of an initially periodic array
and a random initial structure can be described as a coarsening process with
winning grooves temporarily accelerating whereas losing ones decelerate and
even reverse their direction of motion.

</DOC>
<DOC>
<DOCNO> 120940 </DOCNO>
The MACHO Project Hubble Space Telescope Follow-Up: Preliminary Results


  We attempt to determine whether the MACHO microlensing source stars are drawn
from the average population of the LMC or from a population behind the LMC by
examining the HST color-magnitude diagram (CMD) of microlensing source stars.
We present WFPC2 HST photometry of eight MACHO microlensing source stars and
the surrounding fields in the LMC. The microlensing source stars are identified
by deriving accurate centroids in the ground-based MACHO images using
difference image analysis (DIA) and then transforming the DIA coordinates to
the HST frame. We consider in detail a model for the background population of
source stars based on that presented by Zhao, Graff & Guhathakurta. In this
model, the source stars have an additional reddening <E(B-V)> = 0.13 mag and a
slightly larger distance modulus <Delta mu> ~ 0.3 mag than the average LMC
population. We also investigate a series of source star models, varying the
relative fraction of source stars drawn from the average and background
populations and the displacement of the background population from the LMC. Due
to the small number of analyzed events the distribution of probabilities of
different models is rather flat. A shallow maximum occurs at a fraction s_LMC ~
0.8 of the source stars in the LMC. This is consistent with the interpretation
that a significant fraction of observed microlensing events are due to lenses
in the Milky Way halo, but does not definitively exclude other models.

</DOC>
<DOC>
<DOCNO> 102664 </DOCNO>
Induction of Hamiltonian Poisson actions


  We propose a Poisson-Lie analog of the symplectic induction procedure, using
an appropriate Poisson generalization of the reduction of symplectic manifolds
with symmetry. Having as basic tools the equivariant momentum maps of Poisson
actions, the double group of a Poisson-Lie group and the reduction of Poisson
manifolds with symmetry, we show how one can induce a Poisson action admitting
an equivariant momentum map. We prove that, under certain conditions, the
dressing orbits of a Poisson-Lie group can be obtained by Poisson induction
from the dressing orbits of a Poisson-Lie subgroup.

</DOC>
<DOC>
<DOCNO> 13826 </DOCNO>
Disorder Driven Melting of the Vortex Line Lattice


  We use Monte Carlo simulations of the 3D uniformly frustrated XY model, with
uncorrelated quenched randomness in the in-plane couplings, to model the effect
of random point pins on the vortex line phases of a type II superconductor. We
map out the phase diagram as a function of temperature T and randomness
strength p for fixed applied magnetic field. We find that, as p increases to a
critical value p_c, the first order vortex lattice melting line turns parallel
to the T axis, and continues smoothly down to low temperature, rather than
ending at a critical point. The entropy jump across this line at p_c vanishes,
but the transition remains first order. Above this disorder driven transition
line, we find that the helicity modulus parallel to the applied field vanishes,
and so no true phase coherent vortex glass exists.

</DOC>
<DOC>
<DOCNO> 71162 </DOCNO>
Masses and widths of the rho(770)


  Isospin violation in the $\rho(770)$ mass and width is considered within the
$S$ matrix approach using combined fits to the $e^+e^- \to\pi^+\pi^-$ and
$\tau^- \to \nu_{\tau}\pi^-\pi^0$ data performed by the ALEPH collaboration. We
show that the pole position following from the parameters obtained from the
ALEPH fits are not sensitive to the details of the parametrization. In this
context, we have found that the pole mass difference and the pole width
difference between the charged and neutral $\rho$ are consistent with zero. We
show that a one loop calculation including vector, axial vector and
pseudo-scalar mesons can satisfactorily describe the observed isospin breaking.
We also give an estimate for the mass difference between the neutral and
charged states of the $a_1(1260)$.

</DOC>
<DOC>
<DOCNO> 8895 </DOCNO>
Electronic structure of polychiral carbon nanotubes


  Most of the works devoted so far to the electronic band structure of
multiwall nanotubes have been restricted to the case where the individual
layers have the same helicity. By comparison, much less is known on the
electronic properties of multiwall nanotubes that mix different helicities.
These are interesting systems, however, since they can be composed of both
metallic and semiconducting layers. For the present work, tight-binding
calculations were undertaken for polychiral two-layer nanotubes such as
(9,6)@(15,10), (6,6)@(18,2), and others. The recursion technique was used to
investigate how the densities of states of the individual layers are affected
by the intertube coupling. Constant-current STM images were also calculated for
these systems. The result obtained is that the image of a two-wall nanotube is
pretty much the same as the one of the isolated external layer. It is only in
the case of monochiral, commensurate structures like (5,5)@(10,10) that
interlayer effects can be seen on the STM topography.

</DOC>
<DOC>
<DOCNO> 169892 </DOCNO>
Collective versus local measurements on two parallel or antiparallel


  We give a complete analysis of covariant measurements on two spins. We
consider the cases of two parallel and two antiparallel spins, and we consider
both collective measurements on the two spins, and measurements which require
only Local Quantum Operations and Classical Communication (LOCC). In all cases
we obtain the optimal measurements for arbitrary fidelities. In particular we
show that if the aim is determine as well as possible the direction in which
the spins are pointing, it is best to carry out measurements on antiparallel
spins (as already shown by Gisin and Popescu), second best to carry out
measurements on parallel spins and worst to be restricted to LOCC measurements.
If the the aim is to determine as well as possible a direction orthogonal to
that in which the spins are pointing, it is best to carry out measurements on
parallel spins, whereas measurements on antiparallel spins and LOCC
measurements are both less good but equivalent.

</DOC>
<DOC>
<DOCNO> 121217 </DOCNO>
Do clusters contain a large population of dwarf galaxies?


  We analyze systematic effects in the determination of the galaxy luminosity
function in clusters using a deep mock catalogue constructed from a numerical
simulation of a hierarchical universe. The results indicate a strong tendency
to derive a rising faint end ($\alpha \lsim -1.5$) in clusters selected in two
dimensions, using a galaxy catalogue constructed with a universal flat
luminosity function with $\alpha \simeq -1.0$. This is due to the projection
effects inherent in catalogues of clusters constructed using 2 dimensional
data. Many of the clusters found in 2d have no significant 3d counterparts, and
most suffer from massive background contamination that cannot be corrected for
by subtracting random offset fields. The luminosity function of high surface
brightness galaxies in the field and within small groups follows a Schechter
function with a fairly flat faint end slope, $n(L)\propto L^{\alpha}$ with
$\alpha = -0.9$ to -1.2. On the contrary, observational studies of clusters
constructed using Abell, EDCC and APM catalogues are systematically found to
have steeper luminosity functions with $\alpha = -1.4$ to -2.0. This may be
attributed to projection effects rather than a dominant population of high
surface brightness dwarf galaxies ($M\gsim M^*+2$) in clusters. It should be
straighforward to confirm our results by measuring redshifts of these faint
cluster galaxies.

</DOC>
<DOC>
<DOCNO> 151966 </DOCNO>
Partial non-renormalisation of the stress-tensor four-point function in


  We show that, although the correlator of four stress-tensor multiplets in N=4
SYM is known to have radiative corrections, certain linear combinations of its
components are protected from perturbative renormalisation and remain at their
free-field values. This result is valid for weak as well as for strong coupling
and for any gauge group. Our argument uses Intriligator's insertion formula,
and includes a proof that the possible contact term contributions cannot change
the form of the amplitudes. Combining this new non-renormalisation theorem with
Maldacena's conjecture allows us to make a prediction for the structure of the
corresponding correlator in AdS supergravity. This is verified by first
considerably simplifying the strong coupling expression obtained by recent
supergravity calculations, and then showing that it does indeed exhibit the
expected structure.

</DOC>
<DOC>
<DOCNO> 11721 </DOCNO>
Structure of binary Bose-Einstein condensates


  We identify all possible classes of solutions for two-component Bose-Einstein
condensates (BECs) within the Thomas-Fermi (TF) approximation, and check these
results against numerical simulations of the coupled Gross-Pitaevskii equations
(GPEs). We find that they can be divided into two general categories. The first
class contains solutions with a region of overlap between the components. The
other class consists of non-overlapping wavefunctions, and contains also
solutions that do not possess the symmetry of the trap. The chemical potential
and average energy can be found for both classes within the TF approximation by
solving a set of coupled algebraic equations representing the normalization
conditions for each component. A ground state minimizing the energy (within
both classes of the states) is found for a given set of parameters
characterizing the scattering length and confining potential. In the TF
approximation, the ground state always shares the symmetry of the trap.
However, a full numerical solution of the coupled GPEs, incorporating the
kinetic energy of the BEC atoms, can sometimes select a broken-symmetry state
as the ground state of the system. We also investigate effects of finite-range
interactions on the structure of the ground state.

</DOC>
<DOC>
<DOCNO> 84469 </DOCNO>
Non-associative geometry and discrete structure of spacetime


  A new mathematical theory, non-associative geometry, providing a unified
algebraic description of continuous and discrete spacetime, is introduced.

</DOC>
<DOC>
<DOCNO> 119416 </DOCNO>
A Candidate Substellar Companion to HR 7329


  We present the discovery of a candidate substellar companion from a survey of
nearby, young stars with the NICMOS coronagraph on the Hubble Space Telescope.
The H ~ 12 mag object was discovered approximately 4" from the young A0V star
HR 7329. Using follow-up spectroscopy from STIS, we derive a spectral type
between M7V and M8V with an effective temperature of ~ 2600 K. We estimate that
the probability of a chance alignment with a foreground dwarf star of this
nature is ~ 10^(-8) and therefore suggest the object (HR 7329B) is physically
associated with HR 7329 with a projected separation of 200 AU. Current brown
dwarf cooling models indicate a mass of less than 50 Jupiter masses for HR
7329B based on age estimates of < 30 Myr for HR7329A.

</DOC>
<DOC>
<DOCNO> 8706 </DOCNO>
Observation of Individual Josephson Vortices in YBCO Bicrystal


  The response of YBCO bicrystal grain-boundary junctions to small dc magnetic
fields (0 - 10 Oe) has been probed with a low-power microwave (rf) signal of
4.4 GHz in a microwave-resonator setup. Peaks in the microwave loss at certain
dc magnetic fields are observed that result from individual Josephson vortices
penetrating into the grain-boundary junctions under study. The system is
modeled as a long Josephson junction described by the sine-Gordon equation with
the appropriate boundary conditions. Excellent quantitative agreement between
the experimental data and the model has been obtained. Hysteresis effect of dc
magnetic field is also studied and the results of measurement and calculation
are compared.

</DOC>
<DOC>
<DOCNO> 122608 </DOCNO>
Stellar population synthesis models at low and high redshift


  The basic assumptions behind Population Synthesis and Spectral Evolution
models are reviewed. The numerical problems encountered by the standard
population synthesis technique when applied to models with truncated star
formation rates are described. The Isochrone Synthesis algorithm is introduced
as a means to circumvent these problems. A summary of results from the
application of this algorithm to model galaxy spectra by Bruzual and Charlot
(1993, 2000) follows. I present a comparison of these population synthesis
model predictions with observed spectra and color magnitude diagrams for
stellar systems of various ages and metallicities. It is argued that models
built using different ingredients differ in the resulting values of some basic
quantities (e.g. $M/L_V$), without need to invoking violations of physical
principles. The range of allowed colors in the observer frame is explored for
several galaxy redshifts.

</DOC>
<DOC>
<DOCNO> 83484 </DOCNO>
Order-consistent programs are cautiously monotonic


  Some normal logic programs under the answer set (stable model) semantics lack
the appealing property of "cautious monotonicity." That is, augmenting a
program with one of its consequences may cause it to lose another of its
consequences. The syntactic condition of "order-consistency" was shown by Fages
to guarantee existence of an answer set. This note establishes that
order-consistent programs are not only consistent, but cautiously monotonic.
  From this it follows that they are also "cumulative." That is, augmenting an
order-consistent with some of its consequences does not alter its consequences.
In fact, as we show, its answer sets remain unchanged.

</DOC>
<DOC>
<DOCNO> 120165 </DOCNO>
EISily looking for distant clusters of galaxies - - a new algorithm and


  We present a new algorithm to search for distant clusters of galaxies on
catalogues deriving from imaging data, as those of the ESO Imaging Survey. Our
algorithm is a matched filter one, similar to that adopted by Postman et al.
(1996), aiming at identifying cluster candidates by using positional and
photometric data simultaneously. The main novelty of our approach is that
spatial and luminosity filter are run separately on the catalogue and no
assumption is made on the typical size nor on the typical M* for clusters, as
these parameters intervene in our algorithm as typical angular scale (sigma)
and typical apparent magnitude m*. Moreover we estimate the background locally
for each candidate, allowing us to overcome the hazards of inhomogeneous
datasets. As a consequence our algorithm has a lower contamination rate -
without loss of completeness - in comparison to other techniques, as tested
through extensive simulations. We provide catalogues of galaxy cluster
candidates as the result of applying our algorithm to the I-band data of the
EIS-wide patches A and B.

</DOC>
<DOC>
<DOCNO> 170053 </DOCNO>
Common misrepresentation of the Einstein-Podolsky-Rosen argument


  A frequently given version of the argument of Einstein, Podolsky and Rosen
against the completeness of the quantum mechanical description is criticized as
a misrepresentation that lacks the cogency of the original EPR argument.

</DOC>
<DOC>
<DOCNO> 12666 </DOCNO>
Current noise in long diffusive SNS junctions in the incoherent MAR


  Spectral density of current fluctuations at zero frequency is calculated for
a long diffusive SNS junction with low-resistive interfaces. At low
temperature, T << Delta, the subgap shot noise approaches linear voltage
dependence, S=(2/ 3R)(eV + 2Delta), which is the sum of the shot noise of the
normal conductor and voltage independent excess noise. This result can also be
interpreted as the 1/3-suppressed Poisson noise for the effective charge q =
e(1+2Delta/eV) transferred by incoherent multiple Andreev reflections (MAR). At
higher temperatures, anomalies of the current noise develop at the gap
subharmonics, eV = 2Delta/n. The crossover to the hot electron regime from the
MAR regime is analyzed in the limit of small applied voltages.

</DOC>
<DOC>
<DOCNO> 178841 </DOCNO>
Caloric Curves for small systems in the Nuclear Lattice Gas Model


  For pedagogical reasons we compute the caloric curve for 11 particles in a
$3^3$ lattice. Monte-Carlo simulation can be avoided and exact results are
obtained. There is no back-bending in the caloric curve and negative specific
heat does not appear. We point out that the introduction of kinetic energy in
the nuclear Lattice Gas Model modifies the results of the standard Lattice Gas
Model in a profound way.

</DOC>
<DOC>
<DOCNO> 151803 </DOCNO>
A Solvable Toy Model for Tachyon Condensation in String Field Theory


  The lump solution of \phi^3 field theory provides a toy model for unstable
D-branes of bosonic string theory. The field theory living on this lump is
itself a cubic field theory involving a tachyon, two additional scalar fields,
and a scalar field continuum. Its action can be written explicitly because the
fluctuation spectrum of the lump turns out to be governed by a solvable
Schroedinger equation; the \ell=3 case of a series of reflectionless
potentials. We study the multiscalar tachyon potential both exactly and in the
level expansion, obtaining insight into issues of convergence, branches of the
solution space, and the mechanism for removal of states after condensation. In
particular we find an interpretation for the puzzling finite domain of
definition of string field marginal parameters.

</DOC>
<DOC>
<DOCNO> 13744 </DOCNO>
Quantum Tunneling of the Order Parameter in Superconducting Nanowires


  Quantum tunneling of the superconducting order parameter gives rise to the
phase slippage process which controls the resistance of ultra-thin
superconducting wires at sufficiently low temperatures. If the quantum phase
slip rate is high, superconductivity is completely destroyed by quantum
fluctuations and the wire resistance never decreases below its normal state
value. We present a detailed microscopic theory of quantum phase slips in
homogeneous superconducting nanowires. Focusing our attention on relatively
short wires we evaluate the quantum tunneling rate for phase slips, both the
quasiclassical exponent and the pre-exponential factor. In very thin and dirty
metallic wires the effect is shown to be clearly observable even at $T \to 0$.
Our results are fully consistent with recent experimental findings [A.
Bezryadin, C.N. Lau, and M. Tinkham, Nature {\bf 404}, 971 (2000)] which
provide direct evidence for the effect of quantum phase slips.

</DOC>
<DOC>
<DOCNO> 8195 </DOCNO>
Wealth condensation in a simple model of economy


  We introduce a simple model of economy, where the time evolution is described
by an equation capturing both exchange between individuals and random
speculative trading, in such a way that the fundamental symmetry of the economy
under an arbitrary change of monetary units is insured. We investigate a
mean-field limit of this equation and show that the distribution of wealth is
of the Pareto (power-law) type. The Pareto behaviour of the tails of this
distribution appears to be robust for finite range models, as shown using both
a mapping to the random `directed polymer' problem, as well as numerical
simulations. In this context, a transition between an economy dominated by a
few individuals from a situation where the wealth is more evenly spread out, is
found. An interesting outcome is that the distribution of wealth tends to be
very broadly distributed when exchanges are limited, either in amplitude or
topologically. Favoring exchanges (and, less surprisingly, increasing taxes)
seems to be an efficient way to reduce inequalities.

</DOC>
<DOC>
<DOCNO> 151706 </DOCNO>
Abelian Decomposition of SO(2N) Yang-Mills Theory


  Faddeev and Niemi have proposed a decomposition of SU(N) Yang-Mills theory in
terms of new variables, appropriate for describing the theory in the infrared
limit. We extend this method to SO(2N) Yang-Mills theory. We find that the
SO(2N) connection decomposes according to irreducible representations of SO(N).
The low energy limit of the decomposed theory is expected to describe
soliton-like configurations with nontrivial topological numbers. How the method
of decomposition generalizes for $SO(2N+1)$ Yang-Mills theory is also
discussed.

</DOC>
<DOC>
<DOCNO> 120794 </DOCNO>
Neutralinos and the Origin of Radio Halos in Clusters of Galaxies


  We assume that the supersymmetric lightest neutralino is a good candidate for
the CDM and explore the possibility to produce diffuse radio emission from
high-energy electrons arising from the neutralino annihilation in galaxy
clusters whose intracluster medium is filled with a large-scale magnetic field.
We show that these electrons fit the population of seed relativistic electrons
postulated in many models for the origin of cluster radio halos. For magnetic
fields with central values $3 \div 30$ $\mu$G (depending on the DM profile),
the population of seed relativistic electrons from neutralino annihilation can
fit the radio halo spectra of Coma and 1E0657-56. The shape and the frequency
extension of the radio halo spectra are connected with the mass and physical
composition of the neutralino. A pure-gaugino neutralino with mass $M_{\chi}
\geq 80$ GeV can reasonably fit the spectra of both Coma and 1E0657-56. This
model provides a number of extra predictions that make it definitely testable.
On the one hand, it agrees with the observations that {\it (i)} the radio halo
is centered on the cluster dynamical center, usually coincident with the X-ray
center, {\it (ii)} the radio halo surface brightness is similar to the X-ray
one, and {\it (iii)} the monochromatic radio luminosity at 1.4 GHz correlates
strongly with the IC gas temperature. On the other hand, the model predicts
that radio halos should be present in every cluster, which is not actually
observed, although the predicted radio halo luminosities can change by a large
amount ($\sim 10^2 \div 10^6$), depending on the amplitude and the structure of
the IC magnetic field. Also, neutral pions arising from neutralino annihilation
should give rise to substantial gamma-ray emission that could be tested by the
next generation gamma-ray experiments.

</DOC>
<DOC>
<DOCNO> 71544 </DOCNO>
Effects of Strong Magnetic Fields on Neutron Star Structure


  We study static neutron stars with poloidal magnetic fields and a simple
class of electric current distributions consistent with the requirement of
stationarity. For this class of electric current distributions, we find that
magnetic fields are too large for static configurations to exist when the
magnetic force pushes a sufficient amount of mass off-center that the
gravitational force points outward near the origin in the equatorial plane. (In
our coordinates an outward gravitational force corresponds to $\partial\ln
g_{tt}/\partial r>0$, where $t$ and $r$ are respectively time and radial
coordinates and $g_{tt}$ is coefficient of $dt^2$ in the line element.) For the
equations of state (EOSs) employed in previous work, we obtain configurations
of higher mass than had been reported; we also present results with more recent
EOSs. For all EOSs studied, we find that the maximum mass among these static
configurations with magnetic fields is noticeably larger than the maximum mass
attainable by uniform rotation, and that for fixed values of baryon number the
maximum mass configurations are all characterized by an off-center density
maximum.

</DOC>
<DOC>
<DOCNO> 170501 </DOCNO>
Quantum Jumps on a Circle


  It is demonstrated that in contrast to the well-known case with a quantum
particle moving freely in a real line, the wave packets corresponding to the
coherent states for a free quantum particle on a circle do not spread but
develop periodically in time. The discontinuous changes during the course of
time in the phase representing the position of a particle can be interpreted as
the quantum jumps on a circle.

</DOC>
<DOC>
<DOCNO> 99291 </DOCNO>
Nonuniformizable skew cylinders. A counterexample to the simultaneous


  At the end of 1960-ths Yu.S.Ilyashenko stated the problem: is it true that
for any one-dimensional holomorphic foliation with singularities on a Stein
manifold leaves intersecting a transversal disc can be uniformized so that the
uniformization function would depend holomorphically on the transversal
parameter? In the present paper we construct a two-dimensional counterexample.
This together with the previous result of Yu.S.Ilyashenko (Lemma 1) implies
existence of a counterexample given by a foliation on affine (projective)
algebraic surface by level curves of a rational function with singularities
deleted. This implies also that Bers' simultaneous uniformization theorem for
topologically trivial holomorphic foliations by compact Riemann surfaces does
not extend to the general fibrations by compact Riemann surfaces with
singularities.

</DOC>
<DOC>
<DOCNO> 11269 </DOCNO>
Time Arrow in Wave-Packet Evolution


  Availability of short, femtosecond laser pulses has recently made feasible
the probing of phases in an atomic or molecular wave-packet (superposition of
energy eigenstates). With short duration excitations the initial form of the
wave-packet is an essentially real "doorway state", and this develops phases
for each of its component amplitudes as it evolves. It is suggested that these
phases are hallmarks of a time arrow and irreversibility that are inherent in
the quantum mechanical processes of preparation and evolution. To display the
non-triviality of the result, we show under what conditions it would not hold;
to discuss its truth, we consider some apparent contradictions. We propose that
(in time-reversal invariant systems) the preparation of "initially" complex
wave-packets needs finite times to complete, i.e., is not instantaneous.

</DOC>
<DOC>
<DOCNO> 40592 </DOCNO>
Matter effects in oscillations of neutrinos traveling short distances in


  It is well known that when the distance $t$ traveled by neutrinos in matter
is short, matter effects in oscillations of neutrino flavour are small and
decrease with decreasing $t$ more rapidly than the oscillations effects
themselves. We discuss the reason for this and demonstrate that under certain
circumstances this statement is no longer correct. In particular, we show that
if neutrinos propagate significant distances in vacuum before entering matter
(or after exiting it), matter effects in short-$t$ neutrino oscillations can be
significantly enhanced. Implications for oscillations of solar and atmospheric
neutrinos with nearly horizontal trajectories inside the earth and for
accelerator experiments are considered. We also comment on neutrino
oscillations in matter due to flavour changing neutral currents.

</DOC>
<DOC>
<DOCNO> 69903 </DOCNO>
Multi-GeV Neutrinos from Internal Dissipation in GRB Fireballs


  Sub-photospheric internal shocks and transverse differences of the bulk
Lorentz factor in relativistic fireball models of GRB lead to neutron diffusion
relative to protons, resulting in inelastic nuclear collisions. This produces
significant fluxes of ~3 GeV muon neutrinos (antineutrinos) and ~2 GeV electron
neutrinos (antineutrinos), scaling with the Lorentz factor eta < 400. This
extends significantly the parameter space for which neutrinos from inelastic
collision are expected, which in the absence of the above effects requires eta
> 400. A model with sideways diffusion of neutrons from a slower wind into a
fast jet can lead to production of muon and electron neutrinos (antineutrinos)
in the 2-25 GeV or higher range, depending on the value of eta. The emission
from either of these mechanisms at z~1 may be detectable in suitably densely
spaced detectors.

</DOC>
<DOC>
<DOCNO> 12130 </DOCNO>
Dynamics of the frustrated Ising lattice gas


  The dynamical properties of a three dimensional model glass, the frustrated
Ising lattice gas (FILG) are studied by Monte Carlo simulations. We present
results of compression experiments, where the chemical potential is either
slowly or abruptly changed, as well as simulations at constant density. One
time quantities like density and two time ones like correlations, responses and
mean square displacements are measured, and the departure from equilibrium
clearly characterized. The aging scenario, particularly in the case of density
autocorrelations is reminiscent of spin glass phenomenology with violations of
the Fluctuation-dissipation theorem, typical of systems with one replica
symmetry breaking. The FILG, as a valid on-lattice model of structural glasses
can be described with tools developed in spin glass theory and, being a finite
dimensional model, can open the way for a systematic study of activated
processes in glasses.

</DOC>
<DOC>
<DOCNO> 119622 </DOCNO>
Using the acoustic peak to measure cosmological parameters


  Recent measurements of the cosmic microwave background radiation by the
Boomerang experiment indicate that the universe is spatially flat. Here some
simple back-of-the-envelope calculations are used to explain their result. The
main result is a simple formula for the angular scale of the acoustic peak in
terms of the standard cosmological parameters:
l=193*[1+3(1-Omega_0)/5+(1-h)/5+Omega_Lambda/35].

</DOC>
<DOC>
<DOCNO> 170297 </DOCNO>
Coherent control using adaptive learning algorithms


  We have constructed an automated learning apparatus to control quantum
systems. By directing intense shaped ultrafast laser pulses into a variety of
samples and using a measurement of the system as a feedback signal, we are able
to reshape the laser pulses to direct the system into a desired state. The
feedback signal is the input to an adaptive learning algorithm. This algorithm
programs a computer-controlled, acousto-optic modulator pulse shaper. The
learning algorithm generates new shaped laser pulses based on the success of
previous pulses in achieving a predetermined goal.

</DOC>
<DOC>
<DOCNO> 100998 </DOCNO>
Entire functions and compact operators with $S_p$-imaginary component


  We study operators of the form X+Y where Y has a finite p-th Schatten norm
(p<2), and X is self-adjoint and of Hilbert-Schmidt class. Our study is based
on new theorems on zero distribution of entire functions of finite order.

</DOC>
<DOC>
<DOCNO> 40674 </DOCNO>
The Naked Truth about Hadronic Regge Trajectories


  We have reconstructed Regge trajectories (RT), using all existing data on
masses and spin-parities of all currently known hadrons. In this resonance
energy region meson and baryon RT are grossly nonlinear, and only 12% of all RT
could be classified as a linear, with $\sigma=0$, $\alpha'\simeq 0.9$
GeV${}^{-2}$.

</DOC>
<DOC>
<DOCNO> 40200 </DOCNO>
Measurement of the time dependence of B^0-anti-B^0 oscillations using


  A preliminary study of time dependence of B^0-anti-B^0 oscillations using
dilepton events is presented. The flavor of the B meson is determined by the
charge sign of the lepton. To separate signal leptons from cascade and fake
leptons we have used a method which combines several discriminating variables
in a neural network. The time evolution of the oscillations is studied by
reconstructing the time difference between the decays of the B mesons produced
by the Y(4S) decay. With an integrated luminosity of 7.7 fb-1 collected on
resonance by BABAR at the PEP-II asymmetric B Factory, we measure the
difference in mass of the neutral B eigenstates, Delta_mB0, to be
(0.507+/-0.015+/-0.022) x 10^{12} hbar-s^{-1}.

</DOC>
<DOC>
<DOCNO> 13008 </DOCNO>
Hysteretic depinning and dynamical melting for magnetically interacting


  We examine the depinning transitions and the temperature versus driving force
phase diagram for magnetically interacting pancake vortices in layered
superconductors. For strong disorder the initial depinning is plastic followed
by a sharp hysteretic transition to a 3D ordered state for increasing driving
force. Our results are in good agreement with theoretical predictions for
driven anisotropic charge density wave systems. We also show that a temperature
induced peak effect in the critical current occurs due to the onset of
plasticity between the layers.

</DOC>
<DOC>
<DOCNO> 10668 </DOCNO>
Classical Phase Fluctuations in Incommensurate Peierls Chains


  In the pseudogap regime of one-dimensional incommensurate Peierls systems,
fluctuations of the phase of the order parameter prohibit the emergence of
long-range order and generate a finite correlation length. For classical phase
fluctuations, we present exact results for the average electronic density of
states, the mean localization length, the electronic specific heat and the spin
susceptibility at low temperatures. Our results for the susceptibility give a
good fit to experimental data.

</DOC>
<DOC>
<DOCNO> 100082 </DOCNO>
Fusion rings for degenerate minimal models


  We study fusion rings for degenerate minimal models ($p=q$ case) for N=0 and
N=1 (super)conformal algebras. We consider a distinguished family of modules at
the level $c=1$ and $c=3/2$ and show that the corresponding fusion rings are
isomorphic to the representation rings for ${\mathfrak sl}(2, {\bf C})$ and
${\mathfrak osp}(1|2)$ respectively.

</DOC>
<DOC>
<DOCNO> 70376 </DOCNO>
Primordial black hole production due to preheating


  During the preheating process at the end of inflation the amplification of
field fluctuations can lead to the amplification of curvature perturbations. If
the curvature perturbations on small scales are sufficiently large, primordial
black holes (PBHs) will be overproduced. In this paper we study PBH production
in the two-field preheating model with quadratic inflaton potential. We show
that for many values of the inflaton mass m, and coupling g, small scale
perturbations will be amplified sufficiently, before backreaction can shut off
preheating, so that PBHs will be overproduced during the subsequent radiation
dominated era.

</DOC>
<DOC>
<DOCNO> 84765 </DOCNO>
Equivalence principle and radiation by a uniformly accelerated charged


  We address the old question of whether or not a uniformly accelerated charged
particle radiates, and consequently, if weak equivalence principle is violated
by electrodynamics. We show that radiation has different meanings; some
absolute, some relative. Detecting photons or electromagnetic waves is NOT
absolute, it depends both on the electromagnetic field and on the state of
motion of the antenna. An antenna used by a Rindler observer does not detect
any radiation from a uniformly accelerated co-moving charged particle.
Therefore, a Rindler observer cannot decide whether or not he is in an
accelerated lab or in a gravitational field. We also discuss the general case.

</DOC>
<DOC>
<DOCNO> 117191 </DOCNO>
Phase-coherent frequency measurement of the Ca intercombination line at


  The frequency of the Calcium ^3P_1--^1S_0 intercombination line at 657 nm is
phase-coherently measured in terms of the output of a primary cesium frequency
standard using an optical frequency comb generator comprising a sub-10 fs
Kerr-lens mode-locked Ti:Sapphire laser and an external microstructure fiber
for self-phase-modulation. The measured frequency of \nu_Ca = 455 986 240 494
276 Hz agrees within its relative uncertainty of 4 10^-13 with the values
previously measured with a conceptually different harmonic frequency chain and
with the value recommended for the realization of the SI unit of length.

</DOC>
<DOC>
<DOCNO> 71551 </DOCNO>
Self-intersections and gravitational properties of chiral cosmic strings


  Chiral cosmic strings are naturally produced at the end of D-term inflation
and they may have interesting cosmological consequences. As was first proved by
Carter and Peter, the equations of motion for chiral cosmic strings in
Minkowski space are integrable (just as for Nambu-Goto strings). Their
solutions are labeled by a function $k(\sigma - t)$ where $t$ is time and
$\sigma$ is the invariant length along the string, and the constraints on $k$,
which determines the charge on the string, are that $0 \leq k^2 \leq 1$. We
review the origin of this parameter and also discuss some general properties of
such strings which can be deduced from the equations of motion. The metric
around infinite chiral strings is then constructed in the weak field limit, and
studied as a function of $k$. We also consider the angular momentum of circular
chiral loops, and extend previous work to consider the evolution and
self-intersection properties of a more general family of chiral cosmic string
loops for which $k^2(\sigma-t)$ is not constant.

</DOC>
<DOC>
<DOCNO> 100834 </DOCNO>
An example of an asymptotically Hilbertian space which fails the


  Following Davie's example of a Banach space failing the approximation
property [D], we show how to construct a Banach space E which is asymptotically
Hilbertian and fails the approximation property. Moreover, the space E is shown
to be a subspace of a space with an unconditional basis which is ``almost'' a
weak Hilbert space and which can be written as the direct sum of two subspaces
all of whose subspaces have the approximation property.

</DOC>
<DOC>
<DOCNO> 71109 </DOCNO>
When can long-range charge fluctuations serve as a QGP signal?


  We critically discuss recent suggestion to use long-range modes of charge
(electric or baryon) fluctuations as a signal for the presence of Quark-Gluon
Plasma at the early stages of a heavy ion collision. We evaluate the rate of
diffusion in rapidity for different secondaries, and argue that for conditions
of the SPS experiments, it is strong enough to relax the magnitude of those
fluctuations almost to its equilibrium values, given by hadronic ``resonance
gas''. We further argue that experimental data from SPS agree with this
conclusion. We evaluate the detector acceptance needed to measure such
``primordial'' long-range fluctuations at RHIC conditions. We conclude with an
application of the charge fluctuation analysis to the search for the QCD
critical point.

</DOC>
<DOC>
<DOCNO> 121911 </DOCNO>
Prompt High Energy $\gamma$-Ray Emission From the Synchrotron


  In the standard scenario of the fireball model of gamma-ray bursts(GRBs), the
huge initial energy release produces a relativistic blast wave expanding into
the external medium and a reverse shock moving into and heating the fireball
ejecta. We calculate the high energy gamma-ray emission due to inverse Compton
scattering of the synchrotron photons from relativistic electrons in the
reverse shock. Under the favorable values of the physical parameters of the
GRBs and the interstellar medium, our result shows that during the prompt
phase, this emission dominates over the component from the forward shock at
high energy gamma-ray bands. This mechanism can excellently account for the
observations of the prompt high energy gamma-rays detected by EGRET, such as
from GRB930131.

</DOC>
<DOC>
<DOCNO> 80633 </DOCNO>
On the eta-invariant in the 4D chiral U(1) theory


  In contrast to its counterpart in a vector theory, the effective action of a
chiral gauge theory may have a non-vanishing imaginary part. It consists of the
so-called Chern-Simons form, which encodes the anomaly and a gauge invariant
piece related to the eta-invariant of some extended Dirac operator. We
investigate the imaginary part of the effective action in the 4D chiral U(1)
theory within the continuum fermion approach. Perturbative analysis indicates
in general a non-vanishing imaginary part of the effective action. However,
after anomaly cancellation we find only a small value of the imaginary part for
the investigated configurations.

</DOC>
<DOC>
<DOCNO> 11285 </DOCNO>
Aharonov-Bohm Effect for Quasiparticles around a Vortex Line in a D-wave


  On the basis of the Bogolubov-de Gennes theory we develop an analytical
description of low-energy extended quasiparticle states around an isolated flux
line in a superconductor with gap nodes. The wavefunctions of these excitations
and the corresponding density of states are shown to be strongly influenced by
the interaction with a pure gauge potential due to the Aharonov-Bohm scenario.

</DOC>
<DOC>
<DOCNO> 116824 </DOCNO>
RFQ Parameter Choice by Multi-Parameter Optimization


  Experts in different accelerator laboratories accumulated wide experience in
RFQ designing. Nevertheless new tasks on high-power, high-energy CW linac
designing (for example, for ADT applications) were appeared recently. Such
accelerators must be practically free of beam losses. This main condition
placed more stringent requirements upon beam quality at the input of each linac
part. Because RFQ is used as beginning part in above accelerators beam
high-quality requirements is related to RFQ primarily. It means that existing
experience in RFQ designing must be enriching by new approaches and new
methodology

</DOC>
<DOC>
<DOCNO> 151028 </DOCNO>
Indispensability of Ghost Fields and Extended Hamiltonian Formalism in


  It is shown that ghost fields are indispensable in deriving well-defined
antiderivatives in pure space-like axial gauge quantizations of gauge fields.
To avoid inessential complications we confine ourselves to noninteracting
abelian fields and incorporate their quantizations as a continuous deformation
of those in light-cone gauge. We attain this by constructing an axial gauge
formulation in auxiliary coordinates $x^{\mu}= (x^+,x^-,x^1,x^2)$, where
$x^+=x^0{\rm sin}{\theta}+x^3{\rm cos}{\theta}, x^-=x^0{\rm
cos}{\theta}-x^3{\rm sin}{\theta}$ and $x^+$ and $A_-=A^0{\rm cos}
{\theta}+A^3{\rm sin}{\theta}=0$ are taken as the evolution parameter and the
gauge fixing condition, respectively. We introduce $x^-$-independent residual
gauge fields as ghost fields and accomodate them to the Hamiltonian formalism
by applying McCartor and Robertson's method. As a result, we obtain conserved
translational generators $P_{\mu}$, which retain ghost degrees of freedom
integrated over the hyperplane $x^-=$ constant. They enable us to determine
quantization conditions for the ghost fields in such a way that commutation
relations with $P_{\mu}$ give rise to the correct Heisenberg equations. We show
that regularizing singularities arising from the inversion of a hyperbolic
Laplace operator as principal values, enables us to cancel linear divergences
resulting from $({\partial}_-)^{-2}$ so that the Mandelstam- Leibbrandt form of
gauge field propagator can be derived. It is also shown that the pure
space-like axial gauge formulation in ordinary coordinates can be derived in
the limit ${\theta}\to\frac{\pi}{2}-0$ and that the light-cone axial gauge
formulation turns out to be the case of ${\theta}=\frac{\pi}{4}$.

</DOC>
<DOC>
<DOCNO> 102573 </DOCNO>
Getting rid of the negative Schwarzian derivative condition


  In this paper we will show that the assumption on the negative Schwarzian
derivative is redundant in the case of C^3 unimodal maps with a nonflat
critical point. The following theorem will be proved: For any C^3 unimodal map
of an interval with a nonflat critical point there exists an interval around
the critical value such that the first entry map to this interval has negative
Schwarzian derivative. Another theorem proved in the paper provides useful
cross-ratio estimates. Thus, all theorems proved only for unimodal maps with
negative Schwarzian derivative can be easily generalized.

</DOC>
<DOC>
<DOCNO> 70532 </DOCNO>
QCD corrections to top quark spin correlations at hadron colliders


  Future hadron collider experiments will allow for a detailed investigation of
$t\bar{t}$ spin correlation effects. In this talk, recent progress in the
theoretical description of these effects is reported. In particular,
next-to-leading order results for the $t\bar t$ spin correlations in
$q\bar{q}\to t\bar{t}X$ are presented, using various spin quantization axes.

</DOC>
<DOC>
<DOCNO> 84167 </DOCNO>
The Principle of the Fermionic Projector, Introduction and Continuum


  Combining a local gauge principle, the Pauli Exclusion Principle, and the
principles of General Relativity in a particular way, we obtain the
mathematical framework for the formulation of a new type of variational
principle in space-time. The postulate that physics can be formulated within
this framework is called the "principle of the fermionic projector."
  The principle of the fermionic projector is introduced and discussed. We
describe a limiting process with which our variational principles can be
analyzed in the setting of relativistic quantum mechanics and classical field
theory.

</DOC>
<DOC>
<DOCNO> 68707 </DOCNO>
Supersymmetric Dark Matter in the Light of LEP and the Tevatron Collider


  We analyze the accelerator constraints on the parameter space of the Minimal
Supersymmetric extension of the Standard Model, comparing those now available
from LEP II and anticipating the likely sensitivity of Tevatron Run II. The
most important limits are those from searches for charginos, neutralinos and
Higgs bosons at LEP, and searches for stop squarks, charginos and neutralinos
at the Tevatron Collider. We also incorporate the constraints derived from b
--> s + gamma decay, and discuss the relevance of charge- and colour-breaking
minima in the effective potential. We combine and compare the different
constraints on the Higgs-mixing parameter mu, the gaugino-mass parameter
m_{1/2} and the scalar-mass parameter m0, incorporating radiative corrections
to the physical particle masses. We focus on the resulting limitations on
supersymmetric dark matter, assumed to be the lightest neutralino,
incorporating coannihilation effects in the calculation of the relic abundance.
We find that m_chi > 51 GeV and tan(beta) > 2.2 if all soft
supersymmetry-breaking scalar masses are universal, including those of the
Higgs bosons, and that these limits weaken to m_chi > 46 GeV and tan(beta) >
1.9 if non-universal scalar masses are allowed. Light neutralino dark matter
cannot be primarily Higgsino in composition.

</DOC>
<DOC>
<DOCNO> 116239 </DOCNO>
Innovators and Interpreters: The Historic Role of Women in Science


  Until this century, the number of working female scientists has been
indeterminate. Prevailing wisdom indicates that women, historically, have not
excelled in the mathematics and sciences, for various reasons. These range from
societal pressures to marry and bear children, to a lack of systematic
scientific education for females, to the lack of opportunity in institutions
and industry. Women, until comparatively recently, were not in control of their
own financial lives, and were therefore dependent upon the goodwill of a
husband, father or brother, should they attempt to enter academic life. Many
times, their accomplishments, and the accomplishments of these collaborating
relatives, become so merged as to become indistinguishable. Nevertheless, with
all these factors working against them, history records an occasional bright
star. Their diaries, memoirs and correspondence detail both the similarities
and the differences between their roles and the roles of modern female
scientists, in their own minds, and in the estimation of those closest to them.
There exists, in science, a dichotomy between the desire to understand one's
universe, and the desire to change the understanding of others. These two
fundamental desires lead future scientists to the discipline. Historically, the
role of women has largely been interpretive, rather than innovative, by their
own estimation. But is interpretation the "natural" role of women scientists?

</DOC>
<DOC>
<DOCNO> 69045 </DOCNO>
The Effect of a Small Mixing Angle in the Atmospheric Neutrinos


  The effect of matter enhanced neutrino oscillations on atmosheric neutrinos
is investigated systematically in the framework of one mass dominant model of
three neutrinos. The resonance conditions of neutrino crossing the earth are
determined by the three parameters, namely, the zenith angle, ${\Delta m^2/E}$,
and the mixing angle ${\theta_3}$ of the electron neutrinos with tau neutrinos.
The values of the triplet under the resonance is found numerically.

</DOC>
<DOC>
<DOCNO> 81016 </DOCNO>
Fit to Gluon Propagator and Gribov Formula


  We report a numerical study of SU(2) lattice gauge theory in the minimal
Coulomb gauge at beta = 2.2 and 9 different volumes. After extrapolation to
infinite volume, our fit agrees with a lattice discretization of Gribov's
formula for the transverse equal-time would-be physical gluon propagator, that
vanishes like |k| at k = 0, whereas the free equal-time propagator (2|k|)^{-1}
diverges. Our fit lends reality to a confinement scenario in which the would-be
physical gluons leave the physical spectrum while the long-range Coulomb force
confines color.

</DOC>
<DOC>
<DOCNO> 150895 </DOCNO>
Chiral Schwinger models without gauge anomalies


  We find a large class of quantum gauge models with massless fermions where
the coupling to the gauge fields is not chirally symmetric and which
nevertheless do not suffer from gauge anomalies. To be specific we study two
dimensional Abelian models in the Hamiltonian framework which can be
constructed and solved by standard techniques. The general model describes
$\Np$ photon fields and $\Nf$ flavors of Dirac fermions with $2\Nf\Np$
different coupling constants i.e. the chiral component of each fermion can be
coupled to the gauge fields differently. We construct these models and find
conditions so that no gauge anomaly appears. If these conditions hold it is
possible to construct and solve the model explicitly, so that gauge- and
Lorentz invariance are manifest.

</DOC>
<DOC>
<DOCNO> 71744 </DOCNO>
Neutrino Oscillations in Extended Anti-GUT Model


  What we call the Anti-GUT model is extended a bit to include also
right-handed neutrinos and thus make use of the see-saw mechanism for neutrino
masses. This model consists in assigning gauge quantum numbers to the known
Weyl fermions and the three see-saw right-handed neutrinos. Each family
(generation) is given its own Standard Model gauge fields and a gauge field
coupled to the $B-L$ quantum number for that family alone. Further we assign a
rather limited number of Higgs fields, so as to break these gauge groups down
to the Standard Model gauge group and to fit, w.r.t. order of magnitude, the
spectra and mixing angles of the quarks and leptons. We find a rather good fit,
which for neutrino oscillations favours the small mixing angle MSW solution,
although the mixing angle predicted is closest to the upper side of the
uncertainty range for the measured solar neutrino mixing angle. An idea for
making a ``finetuning''-principle to ``explain'' the large ratios found
empirically in physics, and answer such questions as ``why is the weak scale
low compared to the Planck scale?'', is proposed. A further very speculative
extension is supposed to ``explain'' why we have three families.

</DOC>
<DOC>
<DOCNO> 83151 </DOCNO>
XNMR: A tool for knowledge bases exploration


  XNMR is a system designed to explore the results of combining the
well-founded semantics system XSB with the stable-models evaluator SMODELS. Its
main goal is to work as a tool for fast and interactive exploration of
knowledge bases.

</DOC>
<DOC>
<DOCNO> 101393 </DOCNO>
Almost continuous extension for taut foliations


  A taut foliation of a hyperbolic 3-manifold has the continuous extension
property for leaves in almost every direction; that is, for each leaf of the
universal cover of the foliation and almost every geodesic ray in the leaf, the
limit of the ray in the universal cover of the 3-manifold is a well-defined
point in the ideal boundary.

</DOC>
<DOC>
<DOCNO> 9297 </DOCNO>
Perturbation theory methods applied to critical phenomena


  Different perturbation theory treatments of the Ginzburg-Landau phase
transition model are discussed. This includes a criticism of the perturbative
renormalization group (RG) approach and a proposal of a novel method providing
critical exponents consistent with the known exact solutions in two dimensions.
The new values of critical exponents are discussed and compared to the results
of numerical simulations and experiments.

</DOC>
<DOC>
<DOCNO> 40673 </DOCNO>
Statistical Analysis of Solar Neutrino Data


  We calculate with Monte Carlo the goodness of fit and the confidence level of
the standard allowed regions for the neutrino oscillation parameters obtained
from the fit of the total rates measured in solar neutrino experiments. We show
that they are significantly overestimated in the standard method. We also
calculate exact allowed regions with correct frequentist coverage. We show that
the exact VO, LMA and LOW regions are much larger than the standard ones and
merge together giving an allowed band at large mixing angles for all Delta m^2
> 10^{-10} eV^2.

</DOC>
<DOC>
<DOCNO> 169765 </DOCNO>
Resonant cancellation of off-resonant effects in a multilevel qubit


  Off-resonant effects are a significant source of error in quantum
computation. This paper presents a group theoretic proof that off-resonant
transitions to the higher levels of a multilevel qubit can be completely
prevented in principle. This result can be generalized to prevent unwanted
transitions due to qubit-qubit interactions. A simple scheme exploiting dynamic
pulse control techniques is presented that can cancel transitions to higher
states to arbitrary accuracy.

</DOC>
<DOC>
<DOCNO> 9031 </DOCNO>
NMR evidence for a "generalized spin-Peierls transition" in the high


  The magnetic field-induced 3D ordered phase of the two-leg spin-ladder
Cu2(C5N2H12)2Cl4 has been probed through measurements of 1H NMR spectra and
1/T1 in the temperature range 70~mK - 1.2 K. The second order transition line
Tc(H) has been determined between Hc1 = 7.52 T and Hc2 = 13 T and varies as
(H-Hc1)^(2/3) close to Hc1. From the observation of anomalous shifts and a
crossover in 1/T1 above Tc, the mechanism of the 3D transition is argued to be
magnetoelastic, involving a displacement of the protons along the longitudinal
exchange (J//) path.

</DOC>
<DOC>
<DOCNO> 70768 </DOCNO>
Can CP entanglement with the environment mask CP violation?


  We consider departures from hamiltonian dynamics in the evolution of neutral
kaons due to their interactions with the environment that generate entanglement
among them.

</DOC>
<DOC>
<DOCNO> 13185 </DOCNO>
Hysteresis effect in \nu=1 quantum Hall system under periodic


  The effect of a one-dimensional periodic electrostatic modulation on quantum
Hall systems with filling factor \nu=1 is studied. We propose that, either when
the amplitude of the modulation potential or the tilt angle of the magnetic
field is varied, the system can undergo a first-order phase transition from a
fully spin-polarized homogeneous state to a partially spin-polarized
charge-density-wave state, and show hysteresis behavior of the spin
polarization. This is confirmed by our self-consistent numerical calculations
within the Hartree-Fock approximation. Finally we suggest that the \nu=1/3
fractional quantum Hall state may also show similar hysteresis behavior in the
presence of a periodic potential modulation.

</DOC>
<DOC>
<DOCNO> 85073 </DOCNO>
Holonomy in the Schwarzschild-Droste Geometry


  Parallel transport of vectors in curved spacetimes generally results in a
deficit angle between the directions of the initial and final vectors. We
examine such holonomy in the Schwarzschild-Droste geometry and find a number of
interesting features that are not widely known. For example, parallel transport
around circular orbits results in a quantized band structure of holonomy
invariance. We also examine radial holonomy and extend the analysis to spinors
and to the Reissner-Nordstr\"om metric, where we find qualitatively different
behavior for the extremal ($Q = M$) case. Our calculations provide a toolbox
that will hopefully be useful in the investigation of quantum parallel
transport in Hilbert-fibered spacetimes.

</DOC>
<DOC>
<DOCNO> 7679 </DOCNO>
Kinetics of spin coherence of electrons in an undoped semiconductor


  We study the kinetics of spin coherence of optically excited electrons in an
undoped insulating ZnSe/Zn$_{1-x}$Cd$_x$Se quantum well under moderate magnetic
fields in the Voigt configuration. After clarifying the optical coherence and
the spin coherence, we build the kinetic Bloch equations and calculate
dephasing and relaxation kinetics of laser pulse excited plasma due to
statically screened Coulomb scattering and electron hole spin exchange. We find
that the Coulomb scattering can not cause the spin dephasing, and that the
electron-hole spin exchange is the main mechanism of the spin decoherence.
Moreover the beat frequency in the Faraday rotation angle is determined mainly
by the Zeeman splitting, red shifted by the Coulomb scattering and the electron
hole spin exchange. Our numerical results are in agreement with experiment
findings. A possible scenario for the contribution of electron-hole spin
exchange to the spin dephasing of the $n$-doped material is also proposed.

</DOC>
<DOC>
<DOCNO> 40174 </DOCNO>
Inclusive Hadron Production and Dijets at HERA


  This article summarizes a talk given at the International Symposium on
Multiparticle Dynamics 1999 in Providence/USA. It provides an overview on the
variety of measurements of the hadronic final state in jet production for
deep-inelastic scattering and photoproduction at HERA.

</DOC>
<DOC>
<DOCNO> 102512 </DOCNO>
Periodic Monopoles With Singularities And N=2 Super-QCD


  We study solutions of the Bogomolny equation on R^2\times S^1$ with
prescribed singularities. We show that Nahm transform establishes a one-to-one
correspondence between such solutions and solutions of the Hitchin equations on
a punctured cylinder with the eigenvalues of the Higgs field growing at
infinity in a particular manner. The moduli spaces of solutions have natural
hyperkahler metrics of a novel kind. We show that these metrics describe the
quantum Coulomb branch of certain N=2 d=4 supersymmetric gauge theories on
R^3\times S^1. The Coulomb branches of the corresponding uncompactified
theories have been previously determined by E. Witten using the M-theory
fivebrane. We show that the Seiberg-Witten curves of these theories are
identical to the spectral curves associated to solutions of the Bogomolny
equation on R^2\times S^1. In particular, this allows us to rederive Witten's
results without recourse to the M-theory fivebrane.

</DOC>
<DOC>
<DOCNO> 10634 </DOCNO>
On the existence of internal modes of sine-Gordon kinks


  We study whether or not sine-Gordon kinks exhibit internal modes or
``quasimodes.'' By considering the response of the kinks to ac forces and
initial distortions, we show that neither intrinsic internal modes nor
``quasimodes'' exist in contrast to previous reports. However, we do identify a
different kind of internal mode bifurcating from the bottom edge of the phonon
band which arises from the discretization of the system in the numerical
simulations, thus confirming recent predictions.

</DOC>
<DOC>
<DOCNO> 69510 </DOCNO>
Regge Analysis of Diffractive and Leading Baryon Structure Functions


  In this paper we present a combined analysis of the H1 data on leading baryon
and diffractive structure functions from DIS, which are handled as two
components of the same semi-inclusive process. The available structure function
data are analyzed in a series of fits in which three main exchanges are taking
into account: pomeron, reggeon and pion. For each of these contributions, Regge
factorization of the correspondent structure function is assumed. By this
procedure, we extract information about the interface between the diffractive,
pomeron-dominated, region and the leading proton spectrum, which is mostly
ruled by secondary exchanges. One of the main results is that the relative
reggeon contribution to the semi-inclusive structure function is much smaller
than the one obtained from a analysis of the diffractive structure function
alone.

</DOC>
<DOC>
<DOCNO> 71069 </DOCNO>
Exact analytic two-loop expressions for some QCD observables in the


  The author of this work have got explicit expressions for the timelike region
at Next-to-Leading-Order (NLO) as for the coupling function so for QCD
observables. These expressions were compared with approximate ones obtained in
terms of "double logarithms". Next-Next-to-Leading-Order (NNLO) Pade
approximation was also discussed. In this paper some particular role of NLO was
emphasised. It is related with the possibility to express any multi-loop
expressions in terms of the two-loop ones. Thus we can use NLO functions as a
basis of some functional expansion, where higher loop terms incorporation
affects the expansion coefficients only.

</DOC>
<DOC>
<DOCNO> 12108 </DOCNO>
Suppression of matching field effects by splay and pinning energy


  We report measurements of the irreversible magnetization M_i of a large
number of YBa_2Cu_3O_7 single crystals with columnar defects (CD). Some of them
exhibit a maximum in M_i when the density of vortices equals the density of
tracks, at temperatures above 40K. We show that the observation of these
matching field effects is constrained to those crystals where the orientational
and pinning energy dispersion of the CD system lies below a certain threshold.
The amount of such dispersion is determined by the mass and energy of the
irradiation ions, and by the crystal thickness. Time relaxation measurements
show that the matching effects are associated with a reduction of the creep
rate, and occur deep into the collective pinning regime.

</DOC>
<DOC>
<DOCNO> 151119 </DOCNO>
New N=2 supersymmetric gauge theories: The double tensor multiplet and


  The double tensor multiplet of D=4, N=2 supersymmetry, relevant to type IIB
superstring vacua, is derived and its gauge invariant and N=2 supersymmetric
interactions are analysed, both self-interactions and interactions with vector
multiplets and hypermultiplets. Using deformation theory, it is shown that the
lowest dimensional nontrivial interaction vertices of this type have dimension
5 and all dimension 5 vertices are determined. They give rise to new N=2
supersymmetric gauge theories of the `exotic' type which are local but
nonpolynomial in some of the fields and coupling constants. Explicit examples
of such models are constructed.

</DOC>
<DOC>
<DOCNO> 170121 </DOCNO>
Implementation of a Deutsch-like quantum algorithm utilizing


  We describe the experimental implementation of a recently proposed quantum
algorithm involving quantum entanglement at the level of two qubits using NMR.
The algorithm solves a generalisation of the Deutsch problem and distinguishes
between even and odd functions using fewer function calls than is possible
classically. The manipulation of entangled states of the two qubits is
essential here, unlike the Deutsch-Jozsa algorithm and the Grover's search
algorithm for two bits.

</DOC>
<DOC>
<DOCNO> 10983 </DOCNO>
Indication of the ferromagnetic instability in a dilute two-dimensional


  The magnetic field B_c, in which the electrons become fully spin-polarized,
is found to be proportional to the deviation of the electron density from the
zero-field metal-insulator transition in a two-dimensional electron system in
silicon. The tendency of B_c to vanish at a finite electron density suggests a
ferromagnetic instability in this strongly correlated electron system.

</DOC>
<DOC>
<DOCNO> 178932 </DOCNO>
Hypernuclear Physics with Photons


  We review the opportunities and challenges in the field of hypernuclear
physics with electromagnetic probes. An overview is presented regarding our
current understanding of the elementary production process on the nucleon. This
amplitude is then used in the nuclear environment to study the hyperon-nucleon
(YN) interaction. We discuss two scenarios: hypernuclear excitation that allows
the investigation of hypernuclear structure and the bound Lambda in the
nucleus, and quasifree kaon production on the deuteron and on nuclei, which
permits a more direct access to the YN force. Specific examples are given for
few-body systems and shell-model nuclei.

</DOC>
<DOC>
<DOCNO> 100331 </DOCNO>
Noncommutative trigonometry and the A-polynomial of the trefoil knot


  The paper shows the computation of the noncommutative generalization of the
A-polynomial of the trefoil knot. The classical A-polynomial was introduced by
Cooper, Culler, Gillet, Long and Shalen, and was generalized to the context of
Kauffman bracket skein modules by the author in joint work with Frohman and
Lofaro. A major step in determining the noncommutative version of the
A-polynomial of the trefoil is the description of the action of the Kauffman
bracket skein algebra of the torus on the skein module of the knot complement.
As such, the computation reduces to operations with noncommutative
trigonometric functions.

</DOC>
<DOC>
<DOCNO> 69438 </DOCNO>
Anomaly Matching in Gauge Theories at Finite Matter Density


  We investigate the application of 't Hooft's anomaly matching conditions to
gauge theories at finite matter density. We show that the matching conditions
constrain the low-energy quasiparticle spectrum associated with possible
realizations of global symmetries.

</DOC>
<DOC>
<DOCNO> 84210 </DOCNO>
The world is not enough


  We show that the 5-dimensional model introduced by Randall and Sundrum is
(half of) a wormhole, and that this is a general result in models of the RS
type. We also discuss the gravitational trapping of a scalar particle in 5-d
spacetimes. Finally, we present a simple model of brane-world cosmology in
which the background is a static anti-de Sitter manifold, and the location of
the two 3-branes is determined by the technique of ``surgical grafting''.

</DOC>
<DOC>
<DOCNO> 152297 </DOCNO>
Conformal Invariance and Wave-Particle Duality


  We present a conformally invariant generalized form of the free particle
action by connecting the wave and particle aspects through gravity. Conformal
invariance breaking is introduced by choosing a particular configurat$ of
dynamical variables. This leads to the geometrization of the quantum aspects of
matter.

</DOC>
<DOC>
<DOCNO> 169919 </DOCNO>
Defect Mass in Gravitational Field and Red Shift of Atomic and Nuclear


  It is shown, that radiation spectrum of atoms (or nuclei) in the
gravitational field has a red shift since the effective mass of radiating
electrons (or nucleons) changes in this field. This red shift is equal to the
red shift of radiation spectrum in the gravitational field measured in
existence experiments. The same shift must arise when the photon (or $ \gamma $
quantum) is passing through the gravitational field if it participates in
gravitational interactions (photon has no rest mass). The absence of the double
effect in the experiments, probably, means that photons (or $ \gamma $ quanta)
are passing through the gravitational field without interactions.

</DOC>
<DOC>
<DOCNO> 68929 </DOCNO>
A simple interpolation formula for the spectra of power-law and log


  Non-relativistic potential models are considered of the pure power
V(r)=sgn(q) r^q and logarithmic V(r)=ln(r) types. It is shown that, from the
spectral viewpoint, these potentials are actually in a single family. The log
spectra can be obtained from the power spectra by the limit q --> 0 taken in a
smooth representation P(n,l,q) for the eigenvalues E(n,l,q). A simple
approximation formula is developed which yields the first thirty eigenvalues
with error < 0.04%.

</DOC>
<DOC>
<DOCNO> 67664 </DOCNO>
Weak decays Xi_Q -> Lambda_Q pi


  The weak decays Xi_b -> Lambda_b pi and Xi_c -> Lambda_c pi, in which the
heavy quark is not destroyed, are discussed. The branching fractions for these
decays, corresponding to an absolute rate of order 0.01 ps^{-1}, should be at a
one percent level for the b hyperons and at a (few) per mill level for Xi_c,
possibly making feasible their experimental study in future. It is shown,
through an application of the heavy quark limit, the flavor SU(3) symmetry, and
PCAC, that the Delta I = 1/2 rule should hold very well in these decays, and
also that the Xi_b decays are purely S wave in the symmetry limit, while the
difference between the $S$ wave amplitudes of the Xi_c decays and those for the
Xi_b is related, in terms of the heavy quark expansion, to the difference of
the total decay rates within the (Xi_c, Lambda_c) triplet of charmed hyperons.
We also comment on the amplitudes of the semileptonic transitions Xi_Q ->
Lambda_Q l nu and on the weak radiative decays Xi_Q -> Lambda_Q gamma.

</DOC>
<DOC>
<DOCNO> 151081 </DOCNO>
The Paradox of Virtual Dipoles in the Einstein Action


  The functional integral of pure Einstein 4D quantum gravity admits abnormally
large and long-lasting "dipolar fluctuations", generated by virtual sources
with the property Int d^4x Sqrt{g(x)} Tr T(x) = 0. These fluctuations would
exist also at macroscopic scales, with paradoxical consequences. We set out
their general features and give numerical estimates of possible suppression
processes.

</DOC>
<DOC>
<DOCNO> 83170 </DOCNO>
Constraint Programming viewed as Rule-based Programming


  We study here a natural situation when constraint programming can be entirely
reduced to rule-based programming. To this end we explain first how one can
compute on constraint satisfaction problems using rules represented by simple
first-order formulas. Then we consider constraint satisfaction problems that
are based on predefined, explicitly given constraints. To solve them we first
derive rules from these explicitly given constraints and limit the computation
process to a repeated application of these rules, combined with labeling.We
consider here two types of rules. The first type, that we call equality rules,
leads to a new notion of local consistency, called {\em rule consistency} that
turns out to be weaker than arc consistency for constraints of arbitrary arity
(called hyper-arc consistency in \cite{MS98b}). For Boolean constraints rule
consistency coincides with the closure under the well-known propagation rules
for Boolean constraints. The second type of rules, that we call membership
rules, yields a rule-based characterization of arc consistency. To show
feasibility of this rule-based approach to constraint programming we show how
both types of rules can be automatically generated, as {\tt CHR} rules of
\cite{fruhwirth-constraint-95}. This yields an implementation of this approach
to programming by means of constraint logic programming. We illustrate the
usefulness of this approach to constraint programming by discussing various
examples, including Boolean constraints, two typical examples of many valued
logics, constraints dealing with Waltz's language for describing polyhedral
scenes, and Allen's qualitative approach to temporal logic.

</DOC>
<DOC>
<DOCNO> 119373 </DOCNO>
Interpolation of Discretely-Sampled Density Fields


  We present a new technique for the interpolation of discretely-sampled
non-negat ive scalar fields across regions of missing data. Any set of basis
functions can be used, though the method is fastest when they are close to
orthogonal. We sho w how the technique may be efficiently applied when the
discrete sampling rate v aries across the field. Regularisation is desirable to
avoid over-fitting noisy data, and is necessary when the regions of missing
data are larger than the requ ired resolution. We present and investigate
methods for such regularisation.

</DOC>
<DOC>
<DOCNO> 11011 </DOCNO>
Entropy-based analysis of the number partitioning problem


  In this paper we apply the multicanonical method of statistical physics on
the number-partitioning problem (NPP). This problem is a basic NP-hard problem
from computer science, and can be formulated as a spin-glass problem. We
compute the spectral degeneracy, which gives us information about the number of
solutions for a given cost $E$ and cardinality $m$. We also study an extension
of this problem for $Q$ partitions. We show that a fundamental difference on
the spectral degeneracy of the generalized ($Q>2$) NPP exists, which could
explain why it is so difficult to find good solutions for this case. The
information obtained with the multicanonical method can be very useful on the
construction of new algorithms.

</DOC>
<DOC>
<DOCNO> 12243 </DOCNO>
A minimum principle in mRNA editing ?


  mRNA editing of sequences of many species is analyzed. The nature of the
inserted nucleotides and the position of the insertion sites, once fixed the
edited peptide chain, are explained by introducing a minimum principle in the
framework of the crystal basis model of the genetic code introduced by the
authors.

</DOC>
<DOC>
<DOCNO> 116369 </DOCNO>
A non-linear optimal estimation inverse method for radio occultation


  An optimal estimation inverse method is presented which can be used to
retrieve simultaneously vertical profiles of temperature and specific humidity,
in addition to surface pressure, from satellite-to-satellite radio occultation
observations of the Earth's atmosphere. The method is a non-linear, maximum
{\it a posteriori} technique which can accommodate most aspects of the real
radio occultation problem and is found to be stable and to converge rapidly in
most cases. The optimal estimation inverse method has two distinct advantages
over the analytic inverse method in that it accounts for some of the effects of
horizontal gradients and is able to retrieve optimally temperature and humidity
simultaneously from the observations. It is also able to account for
observation noise and other sources of error. Combined, these advantages ensure
a realistic retrieval of atmospheric quantities.
  A complete error analysis emerges naturally from the optimal estimation
theory, allowing a full characterisation of the solution. Using this analysis a
quality control scheme is implemented which allows anomalous retrieval
conditions to be recognised and removed, thus preventing gross retrieval
errors.
  The inverse method presented in this paper has been implemented for bending
angle measurements derived from GPS/MET radio occultation observations of the
Earth. Preliminary results from simulated data suggest that these observations
have the potential to improve NWP model analyses significantly throughout their
vertical range.

</DOC>
<DOC>
<DOCNO> 152493 </DOCNO>
On group averaging for non-compact groups


  We review some aspects of the use of a technique known as group averaging,
which provides a tool for the study of constrained systems. We focus our
attention on the case where the gauge group is non-compact, and a
`renormalized' group averaging method must be introduced. We discuss the
connection between superselection sectors and the rate of divergence of the
group averaging integral.

</DOC>
<DOC>
<DOCNO> 69013 </DOCNO>
On Unitarity Based Relations Between Various Lepton Family Violating


  Simple "unitarity inspired" relations between two- and three-body lepton
flavor violating decays are noted and discussed. In the absence of
cancellations, the existing strong bounds on $\mu \to 3e$ and $ \mu\to
e\gamma\gamma$ severly constrain two-body lepton flavor violating decays.

</DOC>
<DOC>
<DOCNO> 101077 </DOCNO>
New recursions for genus-zero Gromov-Witten invariants


  New relations among the genus-zero Gromov-Witten invariants of a complex
projective manifold $X$ are exhibited. When the cohomology of $X$ is generated
by divisor classes and classes ``with vanishing one-point invariants,'' the
relations determine many-point invariants in terms of one-point invariants.

</DOC>
<DOC>
<DOCNO> 102147 </DOCNO>
On Level Zero Representations of Quantized Affine Algebras


  We study the properties of level zero modules over quantized affine algebras.
The proof of the conjecture on the cyclicity of tensor products by Akasaka and
the present author is given. Several properties of modules generated by
extremal vectors are proved. The weights of a module generated by an extremal
vector are contained in the convex hull of the Weyl group orbit of the
extremalweight. The universal extremal weight module with level zero
fundamental weight as an extremal weight is irreducible, and isomorphic to the
affinization of an irreducible finite-dimensional module.

</DOC>
<DOC>
<DOCNO> 152446 </DOCNO>
Mode regularization of the susy sphaleron and kink: zero modes and


  To obtain the one-loop corrections to the mass of a kink by mode
regularization, one may take one-half the result for the mass of a widely
separated kink-antikink (or sphaleron) system, where the two bosonic zero modes
count as two degrees of freedom, but the two fermionic zero modes as only one
degree of freedom in the sums over modes. For a single kink, there is one
bosonic zero mode degree of freedom, but it is necessary to average over four
sets of fermionic boundary conditions in order (i) to preserve the fermionic
Z$_2$ gauge invariance $\psi \to -\psi$, (ii) to satisfy the basic principle of
mode regularization that the boundary conditions in the trivial and the kink
sector should be the same, (iii) in order that the energy stored at the
boundaries cancels and (iv) to avoid obtaining a finite, uniformly distributed
energy which would violate cluster decomposition. The average number of
fermionic zero-energy degrees of freedom in the presence of the kink is then
indeed 1/2. For boundary conditions leading to only one fermionic zero-energy
solution, the Z$_2$ gauge invariance identifies two seemingly distinct `vacua'
as the same physical ground state, and the single fermionic zero-energy
solution does not correspond to a degree of freedom. Other boundary conditions
lead to two spatially separated $\omega \sim 0 $ solutions, corresponding to
one (spatially delocalized) degree of freedom. This nonlocality is consistent
with the principle of cluster decomposition for correlators of observables.

</DOC>
<DOC>
<DOCNO> 69893 </DOCNO>
Diagonalization of the strongly coupled lattice QCD Hamiltonian


  We construct a solution to the equation of motion of Hamiltonian lattice QCD
in the strong coupling limit using Wilson fermions which exactly diagonalizes
the Hamiltonian to second order in the field operators. This solution obeys the
free lattice Dirac equation with a dynamical mass which is identified with the
gap. The equation determining this gap is derived and it is found that the
dynamical quark mass is a constant to lowest order in N_c but becomes momentum
dependent once 1/N_c corrections are taken into account. We interpret our
solution within the framework of the N-quantum approach to quantum field theory
and discuss how our formalism may be systematically extended to study bound
states at finite temperature and chemical potential.

</DOC>
<DOC>
<DOCNO> 80811 </DOCNO>
Lattice QCD with the Overlap-Dirac Operator: Its $\Lambda$ Parameter,


  We compute the ratio between the scale $\Lambda_L$ associated with a lattice
formulation of QCD using the overlap-Dirac operator, and $\Lambda_{MS-bar}$. To
this end, the one-loop relation between the lattice coupling $g_0$ and the
coupling renormalized in the MS-bar scheme is calculated, using the lattice
background field technique.
   We also compute the one-loop renormalization $Z_\Gamma$ of the two-quark
operators $\bar{\psi} \Gamma \psi$, where $\Gamma$ denotes a generic Dirac
matrix. Furthermore, we study the renormalization of quark bilinears which are
more extended and have better chiral properties.
   Finally, we present improved estimates of $Z_\Gamma$, coming from cactus
resummation and from mean field perturbation theory.

</DOC>
<DOC>
<DOCNO> 80851 </DOCNO>
Perturbative renormalization of the $\Delta B=2$ four-quark operators in


  We present a perturbative calculation of the renormalization constants for
the $\Delta B=2$ four-quark operators, which is needed to evaluate the bag
parameters $B_B$ and $B_S$ in lattice QCD. The one-loop coefficients are
calculated for the $O(1/M)$ NRQCD heavy quark action and the $O(a)$-improved
Wilson action for light quark. Using these coefficients, which remove
$O(\alpha_s/aM)$ error, we reanalyze our previous calculation of the bag
parameters.

</DOC>
<DOC>
<DOCNO> 84250 </DOCNO>
Evolution of the Quantum Friedmann Universe Featuring Radiation


  The classical and quantum models of the Friedmann universe originally filled
with a scalar field and radiation have been studied. The radiation has been
used to specify a reference frame that makes it possible to remove ambiguities
in choosing the time coordinate. Solutions to the Einstein and Schroedinger
equations have been studied under the assumption that the rate of scalar-field
variation is much less than the rate of universe expansion (contraction). It
has been shown that, under certain conditions, the quantum universe can be in
quasistationary states. The probability that the universe goes over to states
with large quantum numbers owing to the interaction of the scalar and
gravitational fields is nonzero. It has been shown that, in the lowest state,
the scale factor is on order of the Planck length. The matter- and
radiation-energy densities in the Planck era have been computed. The possible
scenarios of Universe evolution are discussed.

</DOC>
<DOC>
<DOCNO> 8286 </DOCNO>
Molecular dynamics study of the glass transition in confined water


  A molecular dynamics simulation of SPC/E water confined in a Silica pore is
presented. The pore has been constructed to reproduce the average properties of
a pore of Vycor glass. Due to the confinement and to the presence of a strong
hydrophilic surface, the dynamic behaviour of the liquid appears to be strongly
dependent on the hydration level. The approach to the glass transition of
confined water is investigated on lowering hydration and on supercooling in the
framework of Mode Coupling Theories. At higher hydrations two quite distinct
subsets of water molecules are detectable. Those belonging to the first layer
close to the substrate suffer a severe slowing down, while the remaining ones
display a scenario typical of supercooled liquids approaching the kinetic glass
transition.

</DOC>
<DOC>
<DOCNO> 120733 </DOCNO>
The European Large Area ISO Survey III: 90micron extragalactic source


  We present results and source counts at 90micron extracted from the
Preliminary Analysis of the European Large Area ISO Survey (ELAIS). The survey
covered about 11.6 square degrees of the sky in four main areas and was carried
out with the PHOT instrument onboard the Infrared Space Observatory (ISO). The
survey is at least an order of magnitude deeper than the IRAS 100micron survey
and is expected to provide constraints on the formation and evolution of
galaxies. The majority of the detected sources are associated with galaxies on
optical images. In some cases the optical associations are interacting pairs or
small groups of galaxies suggesting the sample may include a significant
fraction of luminous infrared galaxies. The source counts extracted from a
reliable subset of the detected sources are in agreement with strongly evolving
models of the starburst galaxy population.

</DOC>
<DOC>
<DOCNO> 121243 </DOCNO>
The X-Ray Photoionized Wind in Cen X-3/V779 Cen


  We analyze the ASCA spectrum of the Cen X-3 X-ray binary system in eclipse
using atomic models appropriate to recombination-dominated level population
kinetics in an overionized plasma. In order to estimate the wind
characteristics, we first fit the eclipse spectrum to a single-zone
photoionized plasma model. We then fit spectra from a range of orbital phases
using global models of photoionized winds from the companion star and the
accretion disk that account for the continuous distribution of density and
ionization state. We find that the spectrum can be reproduced by a density
distribution of the form derived by Castor, Abbot, & Klein (1975) for
radiation-driven winds with with the value of the mass-loss rate divided by the
terminal velocity consistent with values for isolated stars of the same stellar
type. This is surprising because the neutron star is very luminous (~10^38
erg/s) and the X-rays from the neutron star should ionize the wind and destroy
the ions that provide the opacity for the radiation-driven wind. Using the same
functional form for the density profile, we also fit the spectrum to a
spherically symmetric wind centered on the neutron star, a configuration chosen
to represent a disk wind. We argue that the relatively modest orbital variation
of the discrete spectrum rules out a disk wind hypothesis.

</DOC>
<DOC>
<DOCNO> 40001 </DOCNO>
Novel DAQ and Trigger Methods for the KLOE experiment


  KLOE, a new state of the art detector recently commissioned for physics
operation at DAFNE, has many innovative interesting features, especially in the
DAQ and Trigger areas. Custom electronics assert a trigger in a 2 microseconds
decision time and distributes it to the FEE with a 50 ps time resolution. Data
are read out using 10 front-end data acquisition chains and sent to a farm of
online servers through a FDDI Gigaswitch. This design of the KLOE DAQ system
allows us to manage an input data rate as high as 50 Mbyte/s, and is completely
scalable by extending the number of computers connected to the switch.

</DOC>
<DOC>
<DOCNO> 40012 </DOCNO>
Technicolor Signatures---Ieri, Oggi e Domani


  We briefly review the basic structure of modern--day technicolor theories. We
then discuss the signatures for technicolor as they were in its early days, the
searches that have been recently performed at the Tevatron and LEP colliders,
and the prospects for testing technicolor in Tevatron Run II and at the LHC.

</DOC>
<DOC>
<DOCNO> 174599 </DOCNO>
Observation of the scissors mode in the quasicontinuum


  The experimental resonance parameters of the pygmy resonance in rare earth
nuclei are compared to global parameters of the scissors-mode states. It is
argued that the pygmy resonance in rare earth nuclei can be described in terms
of orbital M1 strength observed in (gamma,gamma') experiments. The pygmy
resonance is therefore interpreted as the scissors mode in the quasicontinuum.

</DOC>
<DOC>
<DOCNO> 116658 </DOCNO>
Remote sensing of bubble clouds in seawater


  We report on the influence of submerged bubble clouds on the remote sensing
properties of water. We show that the optical effect of bubbles on radiative
transfer and on the estimate of the ocean color is significant. We present a
global map of the volume fraction of air in water derived from daily wind speed
data. This map, together with the parameterization of the microphysical
properties, shows the possible significance of bubble clouds on the albedo of
incoming solar energy

</DOC>
<DOC>
<DOCNO> 102493 </DOCNO>
Chisini's conjecture for curves with singularities of type $x^n=y^m$


  This paper is devoted to a very classical problem that can be summarized as
follows: let S be a non singular compact complex surface, f:S --> P^2 a finite
morphism having simple branching, B the branch curve: to what extent does B
determine f? The problem was first studied by Chisini who proved that B
determines S and f, assuming B to have only nodes and cusps as singularities,
the degree d of f to be greater than 5, and a very strong hypothesis on the
possible degenerations of B, and posed the question if the first or the third
hypothesis could be weakened. Recently Kulikov and Nemirovski proved the result
for d >= 12, and B having only nodes and cusps as singularities. In this paper
we weaken the hypothesis about the singularities of B: we generalize the
theorem of Kulikov and Nemirovski for B having only singularities of type
{x^n=y^m}, in the additional hypothesis of smoothness for the ramification
divisor. Moreover we exhibit a family of counterexamples showing that our
additional hypothesis is necessary.

</DOC>
<DOC>
<DOCNO> 71229 </DOCNO>
Probing the supersymmetric parameter space by WIMP direct detection


  We discuss to which extent the present experiments of direct search for
WIMPs, when interpreted in terms of relic neutralinos, probe interesting
regions of the supersymmetric parameter space, which are also being
progressively explored at accelerators. Our analysis is performed in a number
of different supersymmetric schemes. We derive the relevant neutralino
cosmological properties, locally and on the average in the universe. We prove
that part of the susy configurations probed by current WIMP experiments entail
relic neutralinos of cosmological interest. The main astrophysical and particle
physics uncertainties, relevant for a proper comparison between theory and
experimental data, are stressed and taken into account.

</DOC>
<DOC>
<DOCNO> 7673 </DOCNO>
Bose condensates in a harmonic trap near the critical temperature


  The mean-field properties of finite-temperature Bose-Einstein gases confined
in spherically symmetric harmonic traps are surveyed numerically. The solutions
of the Gross-Pitaevskii (GP) and Hartree-Fock-Bogoliubov (HFB) equations for
the condensate and low-lying quasiparticle excitations are calculated
self-consistently using the discrete variable representation, while the most
high-lying states are obtained with a local density approximation. Consistency
of the theory for temperatures through the Bose condensation point requires
that the thermodynamic chemical potential differ from the eigenvalue of the GP
equation; the appropriate modifications lead to results that are continuous as
a function of the particle interactions. The HFB equations are made gapless
either by invoking the Popov approximation or by renormalizing the particle
interactions. The latter approach effectively reduces the strength of the
effective scattering length, increases the number of condensate atoms at each
temperature, and raises the value of the transition temperature relative to the
Popov approximation. The renormalization effect increases approximately with
the log of the atom number, and is most pronounced at temperatures near the
transition. Comparisons with the results of quantum Monte Carlo calculations
and various local density approximations are presented, and experimental
consequences are discussed.

</DOC>
<DOC>
<DOCNO> 8260 </DOCNO>
Scaling in dynamical Turing pattern formation: density of defects frozen


  We estimate density of defects frozen into a biological Turing pattern which
was turned on at a finite rate. A self-locking of gene expression in individual
cells, which makes the Turing transition discontinuous, stabilizes the pattern
together with its defects. A defect-free pattern can be obtained by spatially
inhomogeneous activation of the genes.

</DOC>
<DOC>
<DOCNO> 117246 </DOCNO>
Mystery of the "Magic Number" 137: Wave Genesis, Theoretical


  That mystery already exists more that 80 years. Many of great theoreticans -
founders of modern physics - Sommerfeld, Ed- dington, Born, Pauli, Dirac, Weyl,
Heisenberg, Feynman, etc. deeply feel its true price, provocative, defiant
character in connection with the fundamental basis of the theoretical phisics.
Is the Fine Structure Constant (FSC) the really fundamental constant or may be
it varies with the time? If that is the really fixed quantity, then - what is
its true, theoretically based value? Fundamental ideas of the Wave Universe
concept open new possibilities to answer that and another incidentally arising
questions

</DOC>
<DOC>
<DOCNO> 69619 </DOCNO>
Polarized Structure Functions g_2 (x) in the Chiral Quark Soliton Model


  The spin-dependent structure functions g_2 (x, Q^2) are investigated within
the framework of the chiral quark soliton model. It turns out that the twist-3
part of g_2 (x, Q^2) gives nonnegligible contributions to the total
distributions at the energy scale of Q^2 = 5 {GeV}^2 but mainly in the smaller
x region only, so that the corresponding third moments \int_0^1 x^2 \bar{g}_2
(x, Q^2) dx are pretty small for both of the proton and neutron in conformity
with the recent E155 data.

</DOC>
<DOC>
<DOCNO> 121438 </DOCNO>
Cosmic Rays above $10^{14}$ eV


  We briefly review the status of cosmic ray studies between $10^{14}$ eV and
the highest observed energies, namely a few times $10^{20}$ eV. Because of the
rather low incident fluxes in this energy range, the studies mostly rely on
ground based, large aperture detectors reconstructing the cosmic ray's
properties through the detection of the air-showers they generate by
interacting with the atmosphere. We stress the fact that many issues such as
the chemical composition of the cosmic rays, their acceleration mechanisms, the
structures displayed in their energy spectrum are mostly open questions which
may be answered by the next generation of experiments.

</DOC>
<DOC>
<DOCNO> 13291 </DOCNO>
Phase diagram of an impurity in the spin-1/2 chain: two channel Kondo


  We consider a magnetic s=1/2 impurity in the antiferromagnetic spin chain as
a function of two coupling parameters: the symmetric coupling of the impurity
to two sites in the chain $J_1$ and the coupling between the two sites $J_2$.
By using field theory arguments and numerical calculations we can identify all
possible fixed points and classify the renormalization flow between them, which
leads to a non-trivial phase diagram. Depending on the detailed choice of the
two (frustrating) coupling strengths, the stable phases correspond either to a
decoupled spin with Curie law behavior or to a non-Fermi liquid fixed point
with a logarithmically diverging impurity susceptibility as in the two channel
Kondo effect. Our results resolve a controversy about the renormalization flow.

</DOC>
<DOC>
<DOCNO> 119808 </DOCNO>
Magnetic field measurements in white dwarfs. Magnetic field, rotation


  This paper describes results of magnetic field measurements of white dwarfs
carried out on the 6-m telescope for the last years. A magnetic field of about
Be ~ 28 kG has been discovered in the degenerate star WD 1953-011.
  A rotational period of WD 0009+501, 1.83 hours, has been discovered, the
average magnetic field of the star is <Be> = -42.3 +/- 5.4 kG and its
semi-amplitude of the rotational variability is 32.0 +/- 6.8 kG. The variable
magnetic field of the bright normal (non-magnetic) degenerate star 40 Eridani B
was confirmed in January 1999 by Zeeman time-resolved spectroscopy. Both the
Halpha and the Hbeta lines give about the same results, we have selected two
best periods in the magnetic field variability, 2h25m and 5h17m. The
semi-amplitude of the rotational variations B_ max ~ 4000-5000 G and the
average field is about zero +/- 500 G. If the magnetic field of 40 Eridani B is
a central dipole, then the rotational axis inclination to the line of sight is
i ~ 90 DEG, and the magnetic axis inclination to the rotational axis is about
the same, beta ~ 90 DEG. For the first time an ultra-high signal-to-noise
spectrum of the white dwarf has been obtained (S/N > 1000). We have found in
this hydrogen-rich DA white dwarf 40 Eridani B (16500 K) that helium abundance
is low (N(He)/N(H) < 10^{-7}), but the spectrum is rich in ultra-weak
absorption lines of metals in low ionization states. It was proposed that these
lines were produced in both circumstellar and interstellar gas.

</DOC>
<DOC>
<DOCNO> 9802 </DOCNO>
A new method for a local study of nonlinear microwave properties of


  We report a set of experimental data on local third-harmonic generation at
microwave frequencies (0.5 GHz) in $YBa_2Cu_3O_7$ and Nb films. For local
investigations of the nonlinear response a probe with inductive coupling was
elaborated. The map of the nonlinear microwave response of a $YBa_2Cu_3O_7$
thin film is plotted below $T_c$ with high resolution. The third-harmonic power
is measured as a function of temperature, input power and dc magnetic field at
some areas of the film. The correlation between the depinning current density
${J_p}$ and the nonlinear microwave response is also demonstrated.

</DOC>
<DOC>
<DOCNO> 10564 </DOCNO>
Quantum shock waves in the Heisenberg XY model


  We show the existence of quantum states of the Heisenberg XY chain which
closely follow the motion of the corresponding semi-classical ones, and whose
evolution resemble the propagation of a shock wave in a fluid. These states are
exact solutions of the Schroedinger equation of the XY model and their
classical counterpart are simply domain walls or soliton-like solutions.

</DOC>
<DOC>
<DOCNO> 151713 </DOCNO>
Superfield Covariant Quantization with BRST Symmetry


  We generalize the method of superfield Lagrangian BRST quantization in the
part of the gauge-fixing procedure and obtain a quantization method that can be
considered as an alternative to the Batalin - Vilkovisky formalism.

</DOC>
<DOC>
<DOCNO> 118620 </DOCNO>
Surface trapping and leakage of low-frequency g-modes in rotating


  A qualitative study of the surface trapping of low-frequency non-radial
g-modes in rotating early-type stars is undertaken within the Cowling,
adiabatic and traditional approximations. It is demonstrated that, at
frequencies below a cut-off, waves cannot be fully trapped within the star, and
will leak through the surface. Expressions for the cut-off frequency are
derived in both the non-rotating and rotating cases; it is found from these
expressions that the cut-off frequency increases with the rotation rate for all
but prograde sectoral modes.
  The results are of possible relevance to the 53 Per and SPB classes of
variable star, which exhibit pulsation frequencies of the same order of
magnitude as the cut-off frequencies found for the stellar model. It is
suggested that observations either of an upper limit on variability periods
(corresponding to the cut-off), or of line-profile variations due to leaking
modes, may permit asteroseismological studies of the outer layers of these
systems.

</DOC>
<DOC>
<DOCNO> 117395 </DOCNO>
Discovery of a Low Surface Brightness Object near Seyfert's Sextet


  We report the discovery of a low surface brightness (LSB) object
serendipitously found during deep CCD imaging of a compact group of galaxies,
Seyfert's Sextet, in VR and I bands. The LSB object is located 2.3 arcmin
southwest from the group center. Its surface brightness within the angular
effective radii of r_e(VR)=4.8 arcsec and r_e(I)=4.8 arcsec is very low ---
mu_e(VR)=25.28 mag arcsec-2 and mu_e(I)=24.47 mag arcsec-2, respectively. The
apparent magnitudes are m_AB(VR)=19.87 mag and m(I)=19.06 mag. The object is
most likely a LSB dwarf galaxy, but other possibilities are also discussed.

</DOC>
<DOC>
<DOCNO> 121072 </DOCNO>
On the Absorption of X-rays in the Interstellar Medium


  We present an improved model for the absorption of X-rays in the ISM intended
for use with data from future X-ray missions with larger effective areas and
increased energy resolution such as Chandra and XMM, in the energy range above
100eV. Compared to previous work, our formalism includes recent updates to the
photoionization cross section and revised abundances of the interstellar
medium, as well as a treatment of interstellar grains and the H2molecule. We
review the theoretical and observational motivations behind these updates and
provide a subroutine for the X-ray spectral analysis program XSPEC that
incorporates our model.

</DOC>
<DOC>
<DOCNO> 120125 </DOCNO>
The HST Survey of BL Lacertae Objects: Morphological Properties of Low


  We report on the optical properties of a sample of 30 BL Lac host galaxies in
the redshift range $0.03<z<0.2$, as derived from HST observations. All galaxies
are fully resolved in the WFPC2 (F702W filter) images, allowing a quantitative
analysis in two dimensions. Most and possibly all these galaxies have
characteristics very similar to those of ``normal'' giant ellipticals. The
luminosity, ellipticity, isophote twisting and amount of disky or boxy
isophotes are consistent with those found in non-active ellipticals and in
radio galaxies. In all cases the BL Lac nucleus is well centered in the main
body of its host galaxy, a result that argues strongly against the microlensing
hypothesis for any significant fraction of the population. A search for faint
sub-structures in the host galaxies has not revealed notable signatures of
tidal distortions or sub-components (faint disks, bars, X features, etc.), and
with only one exception, there are no prominent dusty features in the central
regions. Instead, the BL Lac host galaxies are smooth and unperturbed,
suggesting that strong external gravitational interactions are not important to
ongoing activity. A careful examination of the environment around the nucleus,
however, shows a high incidence of close companion objects, whose nature
remains unclear pending spectroscopic observations.

</DOC>
<DOC>
<DOCNO> 68075 </DOCNO>
Higher Twist Contributions To R-Hadron Phenomenology In The Light Gluino


  The open light gluino window allows non-trivial higher twist gluino
contributions to the proton wave function. Using a two-component model
originally developed for charm hadroproduction, higher twist intrinsic gluino
contributions to final state R-hadron formation are shown to enhance leading
twist production in the forward $x_{F}$ region. We calculate R-hadron
production at $p_{\rm{lab}}=800$ GeV in pp, pBe, and pCu interactions with
light gluino masses of 1.2, 1.5, 3.5, and 5.0 GeV.

</DOC>
<DOC>
<DOCNO> 99601 </DOCNO>
Deformation of singular lagrangian subvarieties


  We investigate deformations of lagrangian manifolds with singularities. We
introduce a complex similar to the de Rham-complex whose cohomology calculates
deformation spaces. Examples of singular lagrangian varieties are presented and
deformations are calculated explicitly.

</DOC>
<DOC>
<DOCNO> 151041 </DOCNO>
Open Superstring and Noncommutative Geometry


  We perform canonical quantization of the open Neveu-Schwarz-Ramond (NSR)
superstrings in the background of a D-brane with the NS B-field. If we choose
the mixed boundary condition as a primary constraint, it generates a set of
secondary constraints. These constraints are easily solved and as a result, the
noncommutative geometry in the bosonic string theory is extended to the
superspace. Solving the constraint conditions we also find that the Hamiltonian
for the superstring is equivalent to a free superstring Hamiltonian on the
target space with the effective open string metric G.

</DOC>
<DOC>
<DOCNO> 150602 </DOCNO>
Kaluza-Klein Black Holes in String Theory


  Non-supersymmetric black holes carrying both electric and magnetic charge
with respect to a single Kaluza-Klein gauge field have much in common with
supersymmetric black holes. Angular momentum conservation and other general
physics principles underlies some of their basic features. Kaluza-Klein black
holes are interpreted in string theory as bound states of D6-branes and
D0-branes. The microscopic theory reproduces the full nonlinear mass formula of
the extremal black holes.

</DOC>
<DOC>
<DOCNO> 69399 </DOCNO>
Spin and Dualization of SU(5) Dyons


  Motivated by the dual standard model, we study the angular momentum spectrum
of stable SU(5) dyons that can be transformed into purely electric states by a
suitable duality rotation i.e. are dualizable. The problem reduces to solving a
Diophantine equation for the holomorphic charges in each topological sector,
but the solutions also have to satisfy certain constraints. We show that these
equations can be solved and sets of dualizable, half-integer spin SU(5) dyons
can be found, each of which corresponds to a single family of the standard
model fermions. We then find two predictions of the dual standard model. First,
the family of half-integer spin, dualizable dyons is accompanied by a set of
dualizable, integer-spin partner states. Secondly, the dyon corresponding to
the electron must necessarily contain non-trivial color internal structure. In
addition, we provide other general results regarding the spectrum of dualizable
dyons and their novel properties, and extend the stability analysis of SU(5)
monopoles used in the dual standard model so far to discuss the stability of
the half-integer spin dyons.

</DOC>
<DOC>
<DOCNO> 11190 </DOCNO>
Signatures of a staggered-flux phase in the t-J model with two holes on


  We study the relevance of the staggered-flux phase in the t-J model using a
system with two holes on a 32-site lattice with periodic boundary conditions.
We find a staggered-flux pattern in the current-current correlation in the
lowest energy d-wave state where there is mutual attraction between the holes.
This staggered correlation decays faster with distance when the hole binding
becomes stronger. This is in complete agreement with a recent study by Ivanov,
Lee and Wen (Phys. Rev. Lett. 84, 3958, (2000)) based on the SU(2) theory, and
strongly suggests that the staggered-flux phase is a key ingredient in the t-J
model. We further show that this staggered-flux pattern does not exist in a
state where the holes repel each other. Correlations of the chirality operator
S_1.(S_2xS_3) show that the staggered pattern of the chirality is closely tied
to the holes.

</DOC>
<DOC>
<DOCNO> 69209 </DOCNO>
Isospin Breaking in the Extraction of Isovector and Isoscalar Spectral


  A finite energy sum rule (FESR) analysis of the isospin-breaking vector
current correlator <0|T(V^3_\mu V^8_\nu)|0> is used to determine the
isospin-breaking electromagnetic (EM) decay constants of the low-lying vector
mesons. These results are used to evaluate the corrections required to extract
the flavor diagonal 33 and 88 resonance contributions from the full resonance
EM contributions to the EM spectral function. A large (~15%) correction is
found in the case of the omega contribution to the isoscalar spectral function.
The implications of these results for sum rules based on the
isovector-isoscalar spectral difference are considered.

</DOC>
<DOC>
<DOCNO> 120589 </DOCNO>
The cluster environments of powerful radio-loud and radio-quiet AGN


  The spatial clustering amplitude (B_{gq}) is determined for a sample of 44
powerful AGN at z~0.2. No significant difference is detected in the richness of
the cluster environments of the radio-loud and radio-quiet sub-samples, both of
which typically inhabit environments as rich as Abell Class ~0. Comparison with
radio luminosity-matched samples from Hill & Lilly (1991) and Wold et al.
(2000a) suggests that there is no epoch-dependent change in environment
richness out to at least z>=0.5 for either radio galaxies or radio quasars.
Comparison with the APM cluster survey shows that, contrary to current
folklore, powerful AGN do not avoid rich clusters, but rather display a spread
in cluster environment which is perfectly consistent with being drawn at random
from the massive elliptical population. Finally, we argue that virtually all
Abell class ~0 clusters contained an active galaxy during the epoch of peak
quasar activity at z~2.5.

</DOC>
<DOC>
<DOCNO> 69297 </DOCNO>
Is There a Third Companion of Lambda and Sigma0?


  The comparison of magnetic moments of neutron and proton reveals three
possible states of a nucleon each composed of quark plus diquark. In this
scheme for the quark content uds there should be three baryons with a different
structure: ud+s, us+d, ds+u. So one can expect the existence of a third
companion to the known baryons Lambda and Sigma0.

</DOC>
<DOC>
<DOCNO> 151938 </DOCNO>
On the correspondence between the classical and quantum gravity


  The relationship between the classical and quantum theories of gravity is
reexamined. The value of the gravitational potential defined with the help of
the two-particle scattering amplitudes is shown to be in disagreement with the
classical result of General Relativity given by the Schwarzschild solution. It
is shown also that the potential so defined fails to describe whatever
non-Newtonian interactions of macroscopic bodies. An alternative interpretation
of the $\hbar^0$-order part of the loop corrections is given directly in terms
of the effective action. Gauge independence of that part of the one-loop
radiative corrections to the gravitational form factors of the scalar particle
is proved, justifying the interpretation proposed.

</DOC>
<DOC>
<DOCNO> 71664 </DOCNO>
Dynamical interpretation of chemical freeze-out in heavy ion collisions


  It is demonstrated that there exists a direct correlation between chemical
freeze-out point and the softest point of the equation of state where the
pressure divided by the energy density, $p(\epsilon)/\epsilon$, has a minimum.
A dynamical model is given as an example where the passage of the softest point
coincides with the condition for chemical freeze-out, namely an average energy
per hadron $\approx$ 1 GeV. The sensitivity of the result to the equation of
state used is discussed.

</DOC>
<DOC>
<DOCNO> 120663 </DOCNO>
On the origin of the Trojan asteroids: Effects of Jupiter's mass


  We present analytic and numerical results which illustrate the effects of
Jupiter's accretion of nebular gas and the planet's radial migration on its
Trojan companions. Initially, we approximate the system by the planar circular
restricted three-body problem and assume small Trojan libration amplitudes.
Employing an adiabatic invariant calculation, we show that Jupiter's
thirty-fold growth from a $10 M_\oplus$ core to its present mass causes the
libration amplitudes of Trojan asteroids to shrink by a factor of about 2.5 to
$\sim 40%$ of their original size. The calculation also shows that Jupiter's
radial migration has comparatively little effect on the Trojans; inward
migration from 6.2 to 5.2 AU causes an increase in Trojan libration amplitudes
of $\sim4%$. In each case, the area enclosed by small tadpole orbits, if made
dimensionless by using Jupiter's semimajor axis, is approximately conserved.
Similar adiabatic invariant calculations for inclined and eccentric Trojans
show that Jupiter's mass growth leaves the asteroid's eccentricities and
inclinations essentially unchanged, while one AU of inward migration causes an
increase in both of these quantities by $\sim 4%$. Numerical integrations
confirm and extend these analytic results. We demonstrate that our predictions
remain valid for Trojans with small libration amplitudes even when the
asteroids have low, but

</DOC>
<DOC>
<DOCNO> 101505 </DOCNO>
Simple Conformal Algebras Generated by Jordan Algebras


  In this article, we first give a short introduction to conformal algebras.
Then we present three families of simple conformal algebras finite growth
generated by simple Jordan algebras of types A, B, C.

</DOC>
<DOC>
<DOCNO> 118797 </DOCNO>
New Developments in Cosmology


  A brief review is given of the present observational data in cosmology. A
review of a new bimetric gravity theory with multiple light cones is presented.
The physical consequences of this gravity theory for the early universe are
analyzed.

</DOC>
<DOC>
<DOCNO> 40407 </DOCNO>
Solar Models: current epoch and time dependences, neutrinos, and


  We calculate accurate solar models and report the detailed time dependences
of important solar quantities. We use helioseismology to constrain the
luminosity evolution of the sun and report the discovery of semi-convection in
evolved solar models that include diffusion. In addition, we compare the
computed sound speeds with the results of p-mode observations by BiSON, GOLF,
GONG, LOWL, and MDI instruments. We contrast the neutrino predictions from a
set of eight standard-like solar models and four deviant (or deficient) solar
models with the results of solar neutrino experiments. For solar neutrino and
for helioseismological applications, we present present-epoch numerical
tabulations of characteristics of the standard solar model as a function of
solar radius, including the principal physical and composition variables, sound
speeds, neutrino fluxes, and functions needed for calculating solar neutrino
oscillations.

</DOC>
<DOC>
<DOCNO> 151925 </DOCNO>
Noether's Theorems and Gauge Symmetries


  Consideration of the Noether variational problem for any theory whose action
is invariant under global and/or local gauge transformations leads to three
distinct theorems. These include the familiar Noether theorem, but also two
equally important but much less well-known results. We present, in a general
form, all the main results relating to the Noether variational problem for
gauge theories, and we show the relationships between them. These results hold
for both Abelian and non-Abelian gauge theories.

</DOC>
<DOC>
<DOCNO> 12113 </DOCNO>
Phase transition in an asymmetric generalization of the zero-temperature


  An asymmetric generalization of the zero-temperature Glauber model on a
lattice is introduced. The dynamics of the particle-density and specially the
large-time behavior of the system is studied. It is shown that the system
exhibits two kinds of phase transition, a static one and a dynamic one.

</DOC>
<DOC>
<DOCNO> 122958 </DOCNO>
Observations of YSO Circumstellar Discs


  We present the results of short baseline interferometry observations at
submillimetre wavelengths, using a two-element interferometer comprising the
JCMT and CSO, of circumstellar discs around young YSOs. We model data for the
Class 0 protostar IRAS03282 and the Class I protostar L1709B with discs and
compare them with previously published results. We find evidence for the ratio
of the disc mass to envelope mass to increase as the objects evolve.

</DOC>
<DOC>
<DOCNO> 7937 </DOCNO>
Charged Excitons in a Dilute 2D Electron Gas in a High Magnetic Field


  A theory of charged excitons X- in a dilute 2D electron gas in a high
magnetic field is presented. In contrast to previous calculations, three bound
X- states (one singlet and two triplets) are found in a narrow and symmetric
GaAs quantum well. The singlet and a "bright" triplet are the two optically
active states observed in experiments. The bright triplet has the binding
energy of about 1 meV, smaller than the singlet and a "dark" triplet. The
interaction of bound X-'s with a dilute 2D electron gas is investigated using
exact diagonalization techniques. It is found that the short-range character of
the e:X- interactions effectively isolates bound X- states from a dilute e-h
plasma. This results in the insensitivity of the photoluminescence spectrum to
the filling factor nu, and an exponential decrease of the oscillator strength
of the dark triplet X- as a function of 1/nu$.

</DOC>
<DOC>
<DOCNO> 101254 </DOCNO>
The Intersection of All Maximum Stable Sets of a Tree and its Pendant


  A stable set in a graph G is a set of mutually non-adjacent vertices,
alpha(G) is the size of a maximum stable set of G, and core(G) is the
intersection of all its maximum stable sets. In this paper we demonstrate that
in a tree T, of order n greater than 1, any stable set of size greater or equal
to n/2 contains at least one pendant vertex. Hence, we deduce that any maximum
stable set in a tree contains at least one pendant vertex. Our main finding is
the theorem claiming that if T does not own a perfect matching, then at least
two pendant vertices an even distance apart belong to core(T). While it is
proved by Levit and Mandrescu that if G is a connected bipartite graph of order
at least 2, then the size of core(G) is different from 1, our new statement
reveals an additional structure of the intersection of all maximum stable sets
of a tree. The above assertions give refining of one result of Hammer, Hansen
and Simeone, stating that if a graph G is of order less than 2*alpha(G), then
core(G) is non-empty, and also of a result of Jamison, Gunter, Hartnel and
Rall, and Zito, saying that for a tree T of order at least two, the size of
core(G) is different from 1.

</DOC>
<DOC>
<DOCNO> 101530 </DOCNO>
Multiresolution Representation for Orbital Dynamics in Multipolar Fields


  We present the applications of variation -- wavelet analysis to
polynomial/rational approximations for orbital motion in transverse plane for a
single particle in a circular magnetic lattice in case when we take into
account multipolar expansion up to an arbitrary finite number and additional
kick terms. We reduce initial dynamical problem to the finite number (equal to
the number of n-poles) of standard algebraical problems. We have the solution
as a multiresolution (multiscales) expansion in the base of compactly supported
wavelet basis.

</DOC>
<DOC>
<DOCNO> 122956 </DOCNO>
Difference Image Analysis of the OGLE-II Bulge Data. I. The Method


  I present an implementation of the difference image photometry based on the
Alard & Lupton optimal PSF matching algorithm. The most important feature
distinguishing this method from the ones using Fourier divisions is that
equations are solved in real space and the knowledge of each PSF is not
required for determination of the convolution kernel. I evaluate the method and
software on 380 GB of OGLE-II bulge microlensing data obtained in 1997--1999
observing seasons. The error distribution is Gaussian to better than 99% with
the amplitude only 17% above the photon noise limit for faint stars. Over the
entire range of the observed magnitudes the resulting scatter is improved by a
factor of 2--3 compared to DoPhot photometry, currently a standard tool in
microlensing searches. For testing purposes the photometry of ~4600 candidate
variable stars and sample difference image data are provided for BUL_SC1 field.
In the candidate selection process, very few assumptions have been made about
the specific types of flux variations, which makes this data set well suited
for general variability studies, including the development of the
classification schemes.

</DOC>
<DOC>
<DOCNO> 101496 </DOCNO>
The geometry of surface-by-free groups


  We show that every word hyperbolic, surface-by-(noncyclic) free group Gamma
is as rigid as possible: the quasi-isometry group of Gamma equals the abstract
commensurator group Comm(Gamma), which in turn contains Gamma as a finite index
subgroup. As a corollary, two such groups are quasi-isometric if and only if
they are commensurable, and any finitely generated group quasi-isometric to
Gamma must be weakly commensurable with Gamma. We use quasi-isometries to
compute Comm(Gamma) explicitly, an example of how quasi-isometries can actually
detect finite index information. The proofs of these theorems involve ideas
from coarse topology, Teichmuller geometry, pseudo-Anosov dynamics, and
singular solv-geometry.

</DOC>
<DOC>
<DOCNO> 116845 </DOCNO>
DFQ--Double Frequency RFQ


  RFQ with a harmonic higher order quadrupole mode is studied. Assuming that we
superpose a higher order mode with twice the frequency of the fundamental mode,
a sawtooth waveform is approximated. In such a case, the bunching function is
enhanced while the transverse stability is modified. Second order longitudinal
harmonic component is also required to enable the effect.

</DOC>
<DOC>
<DOCNO> 121082 </DOCNO>
HST observations of star clusters in NGC 1023: Evidence for three


  Using HST images we have carried out a study of cluster populations in the
nearby S0 galaxy NGC 1023. In two WFPC2 pointings we have identified 221
cluster candidates. The small distance (~9 Mpc) combined with deep F555W and
F814W images allows us to reach about two magnitudes below the expected
turn-over of the globular cluster luminosity function. NGC 1023 appears to
contain at least three identifiable cluster populations: the brighter clusters
show a clearly bimodal color distribution with peaks at V-I = 0.92 and at V-I =
1.15 and in addition there are a number of fainter, more extended objects with
predominantly red colors. Among the brighter clusters, we find that the blue
clusters have somewhat larger sizes than the red ones with mean effective radii
of R(eff) ~ 2 and R(eff) ~ 1.7 pc, respectively. These clusters have luminosity
functions (LFs) and sizes consistent with what is observed for globular
clusters in other galaxies. Fitting Gaussians to the LFs of the blue and red
compact clusters we find turn-over magnitudes of M(TO,blue)=-7.58 and
M(TO,red)=-7.37 in V and dispersions of sigma(V,blue)=1.12 and
sigma(V,red)=0.97. The fainter, more extended clusters have effective radii up
to R(eff) ~ 10-15 pc and their LF appears to rise at least down to M(V) ~ -6,
few of them being brighter than M(V) = -7. We suggest that these fainter
objects may have a formation history distinct from that of the brighter GCs.

</DOC>
<DOC>
<DOCNO> 13130 </DOCNO>
Orbits in Large Aluminum Clusters: Five-Pointed Stars


  The distinctions in the mass spectra of large sodium (Na_N) and aluminum
(Al_N) clusters are discussed. A semiclassical method is used to describe the
shell effects within a spherical jellium model. It allows one to analyze the
relative role of different classical trajectories in the formation of
electronic supershells in clusters of various sizes at zero and finite
temperatures. A criterion for the hardness of the self-consistent potential is
formulated. The conjecture that the five-point-star trajectories make the main
contribution to the spectral oscillations for large soft-potential Al_N
(250<N<900) clusters is substantiated. The computational results are in
agreement with the mass spectra of the Al_N clusters at T ~ 300 K.

</DOC>
<DOC>
<DOCNO> 152298 </DOCNO>
Vacuum-Structure and a Relativistic Pilot Wave


  We study a model for analyzing the effect of a principal violation of the
Lorentz-invariance on the structure of vacuum. The model is based on the
divergence theory developed by Salehi (1997). It is shown that the divergence
theory can be used to model an ensemble of particles. The ensemble is
characterized by the condition that its members are basically at rest in the
rest frame of a preferred inertial observer in vacuum. In this way we find a
direct dynamical interplay between a particle and its associated ensemble. We
show that this effect can be understood in terms of the interaction of a
particle with a relativistic pilot wave through an associated quantum
potential.

</DOC>
<DOC>
<DOCNO> 69107 </DOCNO>
Quark Coalescence and Hadronic Equilibrium


  In a simplified model we study how close can the result of a fast,
non-equilibrium hadronization of quark matter in an expanding fireball come to
hadronic composition in equilibrium. We present a chemical approach to the
simple A+B --> C quark fusion, showing ideal equilibrium constrained by
conservation laws, the fugacity parametrization, as well as linear and
non-linear quark coalescence models as different approximations to this
chemistry. It is shown that color confinement requires a quark density
dependent hadronization cross section.

</DOC>
<DOC>
<DOCNO> 70382 </DOCNO>
Neutrinos and the Supernova Origin of the Elements


  Intense fluxes of neutrinos are emitted by the hot neutron star produced in a
supernova. The electron neutrino and antineutrino capture reactions on neutrons
and protons, respectively, provide heating to drive a wind from the hot neutron
star. The same reactions also determine the neutron-richness of the wind
material. Nucleosynthesis via rapid neutron capture, the r-process, may occur
in the wind material as it expands away from the neutron star. The
neutron-richness of the wind material, and hence, the r-process nucleosynthesis
therein, are sensitive to mixing between the muon (or tauon)
neutrino/antineutrino and the electron (or sterile) neutrino/antineutrino.
Indirect arguments and direct tests for the supernova origin of the r-process
elements are discussed with a goal to establish supernova r-process
nucleosynthesis as an important probe for neutrino mixing.

</DOC>
<DOC>
<DOCNO> 122787 </DOCNO>
Young Clusters in the Magellanic Clouds II


  We present the results of a quantitative study of the degree of extension to
the boundary of the classical convective core within intermediate mass stars.
The basis of our empirical study is the stellar population of four young
populous clusters in the Magellanic Clouds which has been detailed in Keller,
Bessell & Da Costa (2000). The sample affords a meaningful comparison with
theoretical scenarios with varying degrees of convective core overshoot and
binary star fraction. Two critical properties of the population, the
main-sequence luminosity function and the number of evolved stars, form the
basis of our comparison between the observed data set and that simulated from
the stellar evolutionary models. On the basis of this comparison we conclude
that the case of no convective core overshoot is excluded at a 2 sigma level.

</DOC>
<DOC>
<DOCNO> 68674 </DOCNO>
Bounds on "charginos nearly degenerate with the lightest neutralino"


  Though LEP II direct searches still cannot exclude a chargino nearly
degenerate with the lightest neutralino if its mass is only slightly above half
of the Z boson mass and the sneutrino is light, it can be excluded indirectly
analyzing precision data. In this particular limit simple analytical formulas
for oblique electroweak radiative corrections are presented.

</DOC>
<DOC>
<DOCNO> 72135 </DOCNO>
Revisiting Charmless Two-Body B Decays involving $\eta^{\prime}$ and


  We have studied charmless two-body B decays involving $\eta$ and $\eta'$ in
the framework of QCD improved factorization appraoch. The spectator hard
scattering mechanism for $\eta'$ production have been re-examined and extended,
which contributions are incorporated consistently into the factorizable leading
contributions. It is found that the conventional mechanism would give $Br(B\to
\eta' K)\sim 30\times 10^{-6}$ which agrees with predictions based on naive
factorization approaches. With the incorporation of spectator hard scattering
mechanism contributions, theoretical predictions are improved much and the bulk
of $Br(B\to \eta' K)$ are accommodated in the reasonable parameter space. We
have also presented calculations of $g^{\ast}g^{\ast}-\eta^{(\prime)}$
transition form factors within the standard hard scattering approach. It is
shown that the new contributions in the modes such as $B\to \eta' +vector$ and
$B\to \eta+ \pi, \rho, K^{(\ast)}$ are small. Direct CP-violation in those
decay modes are predicted. It is shown that the prospects for measuring direct
CP-violation effects in $B^{\pm} \to$ $\eta' K^{\pm}$, $\eta' \pi^{\pm}$, $\eta
\pi^{\pm}$, and $\eta K^{\pm}$ are promising at B factories in the near future.

</DOC>
<DOC>
<DOCNO> 99995 </DOCNO>
The Dirac Operator and Conformal Compactification


  We give results about the L^2 kernel and the spectrum of the Dirac operator
on a complete Riemannian manifold which is conformally equivalent to the
interior of a Riemannian manifold with nonempty boundary.

</DOC>
<DOC>
<DOCNO> 8406 </DOCNO>
Double-dot charge transport in Si single electron/hole transistors


  We studied transport through ultra-small Si quantum dot transistors
fabricated from silicon-on-insulator wafers. At high temperatures, 4K<T<100K,
the devices show single-electron or single-hole transport through the
lithographically defined dot. At T<4K, current through the devices is
characterized by multidot transport. From the analysis of the transport in
samples with double-dot characteristics, we conclude that extra dots are formed
inside the thermally grown gate oxide which surrounds the lithographically
defined dot.

</DOC>
<DOC>
<DOCNO> 118235 </DOCNO>
Structure of the Sagittarius dwarf galaxy at low Galactic latitudes


  We report the detection of $\sim$ 1500 RR Lyrae of Bailey type ab located in
the Sagittarius dwarf galaxy (Sgr). These variables have been detected on two
ESO Schmidt fields centred on (l,b)=(3.1 deg,-7.1 deg) and (6.6 deg, -10.8
deg), covering an area of $\sim$50 square degree. We present a surface density
map of Sgr based on the spatial distribution of these RRab, allowing us to
trace its structure in a region that was still almost unexplored between b=-14
deg and b=-4 deg. We present the results of the fit of different models to the
density profile of Sgr. The best fit to the core of Sgr is an exponential with
a scale length of 4.1 deg along the major axis. When we look at the extension
of Sgr we find a break (significant at the $\sim2\sigma$ level) in the slope of
the surface density along the main axis of Sgr. The nearly flat (or at least
very slowly decreasing) profile in the outer region of Sgr shows that this
dwarf galaxy is probably extending even further out our fields.

</DOC>
<DOC>
<DOCNO> 102699 </DOCNO>
Operators Extending (Pseudo-)Metrics


  We introduce a general method of extending (pseudo-)metrics from X to FX,
where F is a normal functor on the category of metrizable compacta. For many
concrete instances of F, our method specializes to the known constructions.

</DOC>
<DOC>
<DOCNO> 68198 </DOCNO>
Central rapidity densities of charged particles at RHIC and LHC


  Predictions on central rapidity densities of charged particles at energies of
the Relativistic Heavy Ion Collider and the Large Hadron Collider, for central
collisions between the largest nuclei that will be available at these
accelerators, are reviewed. Differences among the results of the existing
models are discussed in relation with their underlying physical basis and with
the possibilities to discriminate them.

</DOC>
<DOC>
<DOCNO> 150741 </DOCNO>
Decomposing Quantum Fields on Branes


  We provide a method to decompose the two-point function of a quantum field on
a warped manifold in terms of fields living on a lower-dimensional manifold. We
discuss explicit applications to Minkowski, de Sitter and anti-de Sitter
quantum field theories. This decomposition presents a remarkable analogy with
the holography principle, in the sense that physics in d+1 dimensions may be
encoded into the physics in one dimension less. Moreover in a context a la
Randall--Sundrum, the method outlined here allows a mechanism of generation of
mass-spectra in the 3-brane (or more generally a d-1-brane).

</DOC>
<DOC>
<DOCNO> 13126 </DOCNO>
Statistical thermodynamics of quantum Brownian motion: Birth of


  The Brownian motion of a quantum particle in a harmonic confining potential
and coupled to a harmonic quantum thermal bath is exactly solvable. It is shown
that at low enough temperatures the stationary state is non-Gibbsian due to an
entanglement with the bath. In physical terms, this happens when the cloud of
bath modes around the particle starts to play a non-trivial role. Indeed,
equilibrium thermodynamics of the total system, particle plus bath, does not
imply standard equilibrium thermodynamics for the particle itself at low $T$.
Various formulations of the second law are found to be invalid at low $T$.
First, the Clausius inequality can be violated, because heat can be extracted
from the zero point energy of the cloud of bath modes. Second, when the width
of the confining potential is suddenly changed, there occurs a relaxation to
equilibrium during which the entropy production is partly negative. Third, for
non-adiabatic changes of system parameters the rate of energy dissipation can
be negative, and, out of equilibrium, cyclic processes are possible which
extract work from the bath. Conditions are put forward under which perpetuum
mobile of the second kind, having one or several work extraction cycles, enter
the realm of condensed matter physics. Fourth, it follows that the equivalence
between different formulations of the second law (e.g. those by Clausius and
Thomson) can be violated at low temperatures. These effects are the consequence
of quantum entanglement in the presence of the slightly off-equilibrium nature
of the thermal bath, and become important when the characteristic quantum time
scale $\hbar/k_BT$ is larger than or comparable to other timescale of the
system. They show that there is no general consensus between standard
thermodynamics and quantum mechanics.

</DOC>
<DOC>
<DOCNO> 174568 </DOCNO>
Sturcture of the Goldstone Bosons


  The feasibility of measuring the pion and kaon structure functions has been
investigated. A high luminosity electron-proton collider would make these
measurements feasible. Also, it appears feasible to measure these structure
functions in a nuclear medium. Simulations using the RAPGAP Monte Carlo of a
possible pion structure function measurement are presented.

</DOC>
<DOC>
<DOCNO> 122651 </DOCNO>
Incidence and survival of remnant disks around main-sequence stars


  We present photometric ISO 60 and 170um measurements, complemented by some
IRAS data at 60um, of a sample of 84 nearby main-sequence stars of spectral
class A, F, G and K in order to determine the incidence of dust disks around
such main-sequence stars. Of the stars younger than 400 Myr one in two has a
disk; for the older stars this is true for only one in ten. We conclude that
most stars arrive on the main sequence surrounded by a disk; this disk then
decays in about 400 Myr. Because (i) the dust particles disappear and must be
replenished on a much shorter time scale and (ii) the collision of
planetesimals is a good source of new dust, we suggest that the rapid decay of
the disks is caused by the destruction and escape of planetesimals. We suggest
that the dissipation of the disk is related to the heavy bombardment phase in
our Solar System. Whether all stars arrive on the main sequence surrounded by a
disk cannot be established: some very young stars do not have a disk. And not
all stars destroy their disk in a similar way: some stars as old as the Sun
still have significant disks.

</DOC>
<DOC>
<DOCNO> 102635 </DOCNO>
O-minimal cohomology and definably compact definable groups


  Let N be an o-minimal expansion of a real closed field. We develop cohomology
theory for the category of N-definable manifolds and N-definable maps, and use
this to solve the Peterzil-Steinhorn problem on the existence of torsion points
on N-definably compact N-definable abelian groups. We compute the cohomology
rings of N-definably compact N-definable groups, and we prove an o-minimal
analog of the Poincare duality theorem, the Alexander dualti theorem, the
Lefschetz duality theorem and the Lefschetz fixed point theorem.

</DOC>
<DOC>
<DOCNO> 121712 </DOCNO>
The use of the NEXTGEN model atmospheres for cool giants in a light


  We have written a light curve synthesis code that makes direct use of model
atmosphere specific intensities, in particular the NEXTGEN model atmosphere
grid for cool giants (T_eff <= 6800 K and log(g) <= 3.5, Hauschildt et al.
1999). We point out that these models (computed using spherical geometry)
predict a limb darkening behaviour that deviates significantly from a simple
linear or two-parameter law (there is less intensity at the limb of the star).
The presence of a significantly nonlinear limb darkening law has two main
consequences. First, the ellipsoidal light curve computed for a tidally
distorted giant using the NEXTGEN intensities is in general different from the
light curve computed using the same geometry but with the black body
approximation and a one- or two-parameter limb darkening law. In most cases the
light curves computed with the NEXTGEN intensities have deeper minima than
their black body counterparts. Thus the light curve solutions for binaries with
a giant component obtained with models with near linear limb darkening (either
black body or plane-parallel model atmosphere intensities) are biased.
Observations over a wide wavelength range (i.e. both the optical and infrared)
are particularly useful in discriminating between models with nearly linear
limb darkening and the NEXTGEN models. Second, we show that rotational
broadening kernels for Roche lobe filling (or nearly filling) giants can be
significantly different from analytic kernels due to a combination of the
nonspherical shape of the star and the radical departure from a simple limb
darkening law. As a result, geometrical information inferred from V_rot*sin(i)
measurements of cool giants in binary systems are likewise biased.

</DOC>
<DOC>
<DOCNO> 118057 </DOCNO>
Reconstructing the Star Formation History of the Galaxy


  The evolution of the star formation rate in the Galaxy is one of the key
ingredients quantifying the formation and determining the chemical and
luminosity evolution of galaxies. Many complementary methods exist to infer the
star formation history of the components of the Galaxy, from indirect methods
for analysis of low-precision data, to new exact analytic methods for analysis
of sufficiently high quality data. We summarise available general constraints
on star formation histories, showing that derived star formation rates are in
general comparable to those seen today. We then show how colour-magnitude
diagrams of volume- and absolute magnitude-limited samples of the solar
neighbourhood observed by Hipparcos may be analysed, using variational calculus
techniques, to reconstruct the local star formation history. The remarkable
accuracy of the data coupled to our maximum-likelihood variational method
allows objective quantification of the local star formation history with a time
resolution of ~ 50 Myr. Over the past 3Gyr, the solar neighbourhood star
formation rate has varied by a factor of ~ 4, with characteristic timescale
about 0.5Gyr, possibly triggered by interactions with spiral arms.

</DOC>
<DOC>
<DOCNO> 13042 </DOCNO>
Quantum spin ladder systems associated with su(2|2)


  Two integrable quantum spin ladder systems will be introduced associated with
the fundamental su(2|2) solution of the Yang-Baxter equation. The first model
is a generalized quantum Ising system with Ising rung interactions. In the
second model the addition of extra interactions allows us to impose Heisenberg
rung interactions without violating integrability. The existence of a Bethe
ansatz solution for both models allows us to investigate the elementary
excitations for antiferromagnetic rung couplings. We find that the first model
does not show a gap whilst in the second case there is a gap for all positive
values of the rung coupling.

</DOC>
<DOC>
<DOCNO> 151266 </DOCNO>
Noncritical Strings, RG Flows and Holography


  We derive an RG flow equation that is satisfied by the regularized partition
function for noncritical strings in background fields. The flow refers to
change in the position of a ``boundary'' in the liouville direction. The
boundary is required to regularize the ultraviolet divergences in the partition
function coming from integration over world-sheets of arbitrarily small area.
  From the point of view of the target space effective gravitational action
that the partition function evaluates on-shell, the boundary regularizes {\it
infrared} divergences coming from the infinite volume of the liouville
direction. The RG flow equation that we obtain looks very much like the
Hamilton-Jacobi constraint equation that an on-shell gauge-fixed gravitational
action must satisfy.

</DOC>
<DOC>
<DOCNO> 72125 </DOCNO>
Do precision electroweak constraints guarantee $\epem$ collider


  The manner in which the parameters of a two-Higgs-doublet model can be chosen
so that no Higgs boson is discovered at a $\sqrt{s}\leq 800\gev$ $\epem$
collider, while maintaining consistency with current precision electroweak
measurements, is described. The importance of a Giga-$Z$ factory and higher
collider energies for such a scenario is emphasized.

</DOC>
<DOC>
<DOCNO> 120351 </DOCNO>
The Onset of Methane in L Dwarfs


  We have detected weak absorption features produced by the strong nu(3)
methane band at 3.3 microns in two L dwarfs, 2MASSW J1507476-162738 and 2MASSI
J0825196+211552, classified by Kirkpatrick et al. (2000) as spectral types L5
and L7.5 respectively. These absorptions occur in objects warmer than any in
which methane previously has been detected, and mark the first appearance of
methane in the ultracool star-to-brown dwarf spectral sequence.

</DOC>
<DOC>
<DOCNO> 123267 </DOCNO>
Deep BVR photometry of the Chandra Deep Field South from the COMBO-17


  We report on deep multi-color imaging (R_5-sigma = 26) of the Chandra Deep
Field South, obtained with the Wide Field Imager (WFI) at the MPG/ESO 2.2 m
telescope on La Silla as part of the COMBO-17 survey. As a result we present a
catalog of 63501 objects in a field measuring 31.5' x 30' with astrometry and
BVR photometry. A sample of 37 variable objects is selected from two-epoch
photometry. We try to give interpretations based on color and variation
amplitude.

</DOC>
<DOC>
<DOCNO> 8461 </DOCNO>
Wetting-induced effective interaction potential between spherical


  Using a density functional based interface displacement model we determine
the effective interaction potential between two spherical particles which are
immersed in a homogeneous fluid such as the vapor phase of a one-component
substance or the A-rich liquid phase of a binary liquid mixture composed of A
and B particles. If this solvent is thermodynamically close to a first-order
fluid-fluid phase transition, the spheres are covered with wetting films of the
incipient bulk phase, i.e., the liquid phase or the B-rich liquid,
respectively. Below a critical distance between the spheres their wetting films
snap to a bridgelike configuration. We determine phase diagrams for this
morphological transition and analyze its repercussions on the effective
interaction potential. Our results are accessible to force microscopy and may
be relevant to flocculation in colloidal suspensions.

</DOC>
<DOC>
<DOCNO> 116276 </DOCNO>
Monodisperse approximation in the metastable phase decay


  A new simple method for the first order phase transition kinetics is
suggested. The metastable phase consumption can be imagined in frames of the
modisperse approximation for the distribution of the droplets sizes. In all
situations of the metastable phase decay this approximation leads to negligible
errors in the total number of droplets appeared in the system. An evident
advantage of the presented method is the possibility to investigate the
situation of the metastable phase decay on several sorts of heterogeneous
centers.

</DOC>
<DOC>
<DOCNO> 69104 </DOCNO>
A calculation of the transport coefficients of hot and dense hadronic


  We evaluate thermodynamical quantities and the transport coefficients of a
dense and hot hadronic matter based on the event generator URASiMA
(Ultra-Relativistic AA collision Simulator based on Multiple Scattering
Algorithm) with periodic boundary conditions. As the simplest example of the
transport coefficients we investigate the temperature dependence and the
chemical potential dependence of the baryon diffusion constant of a dense and
hot hadronic matter.

</DOC>
<DOC>
<DOCNO> 68110 </DOCNO>
HELAC: a package to compute electroweak helicity amplitudes


  HELAC is a FORTRAN based package that is able to compute efficiently helicity
amplitudes for arbitrary scattering processes within the standard electroweak
theory. The algorithm exploits the virtues of the Dyson-Schwinger equations as
compared to the traditional Feynman graph approach. All electroweak vertices
are included in both the unitary and Feynman gauges, and computations including
all mass effects are available. A version performing multi-precision
computations with arbitrary - user defined - accuracy is also included,
allowing access to any phase space point for arbitrary high energies.

</DOC>
<DOC>
<DOCNO> 116535 </DOCNO>
Harmonically dancing space-time nodes: quantitatively deriving


  The microscopic structure of space and time is investigated. It is proposed
that space and time of an inertial observer $\Sigma$ are most conveniently
described as a crystal array $\Lambda$, with nodes representing measurement
`tickmarks' and connected by independent quantized harmonic oscillators which
vibrate more severely the faster $\Sigma$ moves with respect to the object
being measured (due to the Uncertainty Principle). The Lorentz transformation
of Special Relativity is derived. Further, mass is understood as a localized
region $\Delta \Lambda$ having higher vibration temperature than that of the
ambient lattice. The effect of relativistic mass increase may then be
calculated without appealing to energy-momentum conservation. The origin of
gravitation is shown to be simply a transport of energy from the boundary of
$\Delta \Lambda$ outwards by lattice phonon conduction, as the system tends
towards equilibrium. Application to a single point mass leads readily to the
Schwarzschild metric, while a new solution is available for two point masses -
a situation where General Relativity is too complicated to work with. The
important consequence is that inertial observers who move at relative speeds
too close to $c$ are no longer linked by the Lorentz transformation, because
the lattice of the `moving' observer has already disintegrated into a liquid
state.

</DOC>
<DOC>
<DOCNO> 10335 </DOCNO>
Squeezed Condensates


  We analyse the atomic state obtained by photo-dissociation of a molecular
Bose-Einstein-condensate. This process is equivalent to down-conversion in
quantum optics where it is responsible for squeezing of the field amplitudes.
Monte Carlo simulations derived from the Positive P description of the system,
and approximate equations for second moments of the atomic field operators are
introduced to describe the early stages of the process -- not amenable to the
usual mean-field description.

</DOC>
<DOC>
<DOCNO> 117909 </DOCNO>
The discovery of a low mass, pre-main-sequence stellar association


  We report the serendipitous discovery of a population of low mass, pre-main
sequence stars (PMS) in the direction of the Wolf-Rayet/O-star binary system
gamma^{2} Vel and the Vela OB2 association. We argue that gamma^{2} Vel and the
low mass stars are truly associated, are approximately coeval and that both are
at distances between 360-490 pc, disagreeing at the 2 sigma level with the
recent Hipparcos parallax of gamma^{2} Vel, but consistent with older distance
estimates. Our results clearly have implications for the physical parameters of
the gamma^{2} Vel system, but also offer an exciting opportunity to investigate
the influence of high mass stars on the mass function and circumstellar disc
lifetimes of their lower mass PMS siblings.

</DOC>
<DOC>
<DOCNO> 120366 </DOCNO>
Radio - Optical Correlations in High-z Radio Galaxies and Quasars


  The narrow emission line luminosities of radio-loud AGN are well-correlated
with their low-frequency radio luminosities. This correlation is linear and
extends over at least four orders of magnitude. The correlation is discussed in
terms of a linear relationship between the power in the radio-emitting jets and
the photoionizing (i.e. accretion) luminosity. Support for this theory comes
from a direct correlation between the optical continuum and radio luminosities
of steep-spectrum quasars. We discuss the dependence of the observed
luminosities of AGN on their black hole masses and how close to the Eddington
limit they are accreting.

</DOC>
<DOC>
<DOCNO> 101649 </DOCNO>
On the Albanese map for smooth quasi-projective varieties


  Let k be an algebraically closed field and X a smooth projective k-variety. A
famous theorem of A. A. Roitman states that the canonical map from the degree
zero part of the Chow group of zero cycles on X to the group of k-points of its
Albanese variety induces an isomorphism on torsion prime to the characteristic
of k. In the present paper we prove a generalisation to quasi-projective
varieties admitting a smooth compactification. As was first observed by
Ramachandran, for such a generalisation one should replace the Chow group of
zero cycles by Suslin's 0-th algebraic singular homology group and the Albanese
variety by the generalised Albanese of Serre. The method of proof is new even
in the projective case and makes the motivic nature of the Albanese
transparent. We also prove that the generalised Albanese map is an isomorphism
if k is the algebraic closure of a finite field.

</DOC>
<DOC>
<DOCNO> 13902 </DOCNO>
Analytical approximation for reaction-diffusion processes in rough pores


  The concept of an active zone in Laplacian transport is used to obtain an
analytical approximation for the reactive effectiveness of a pore with an
arbitrary rough geometry. We show that this approximation is in very good
agreement with direct numerical simulations performed over a wide range of
diffusion-reaction conditions (i.e., with or without screening effects). In
particular, we find that in most practical situations, the effect of roughness
is to increase the intrinsic reaction rate by a geometrical factor, namely, the
ratio between the real and the apparent surface area. We show that this simple
geometrical information is sufficient to characterize the reactive
effectiveness of a pore, in spite of the complex morphological features it
might possess.

</DOC>
<DOC>
<DOCNO> 150481 </DOCNO>
Solitons in Brane Worlds II


  We study the solution describing a non-extreme dilatonic (p+1)-brane
intersecting a D-dimensional extreme dilatonic domain wall, where one of its
longitudinal directions is along the direction transverse to the domain wall,
in relation to the Randall-Sundrum type model. The dynamics of the probe
(p+1)-brane in such source background reproduces that of the probe p-brane in
the background of the (D-1)-dimensional source p-brane. However, as for a probe
test particle, the dynamics in one lower dimensions is reproduced, only when
the source (p+1)-brane is uncharged.

</DOC>
<DOC>
<DOCNO> 101631 </DOCNO>
On the Implementation of Constraints through Projection Operators


  Quantum constraints of the type Q \psi = 0 can be straightforwardly
implemented in cases where Q is a self-adjoint operator for which zero is an
eigenvalue. In that case, the physical Hilbert space is obtained by projecting
onto the kernel of Q, i.e. H_phys = ker(Q) = ker(Q*). It is, however,
nontrivial to identify and project onto H_phys when zero is not in the point
spectrum but instead is in the continuous spectrum of Q, because in this case
the kernel of Q is empty.
  Here, we observe that the topology of the underlying Hilbert space can be
harmlessly modified in the direction perpendicular to the constraint surface in
such a way that Q becomes non-self-adjoint. This procedure then allows us to
conveniently obtain H_phys as the proper Hilbert subspace H_phys = ker(Q*), on
which one can project as usual. In the simplest case, the necessary change of
topology amounts to passing from an L^2 Hilbert space to a Sobolev space.

</DOC>
<DOC>
<DOCNO> 100309 </DOCNO>
Topological properties of real algebraic varieties: du c\^ot\'e de chez


  The survey gives an overview of the achievements in topology of real
algebraic varieties in the direction initiated in the early 70th by V.I.Arnold
and V.A.Rokhlin. We make an attempt to systematize the principal results in the
subject. After an exposition of general tools and results, special attention is
paid to surfaces and curves on surfaces.

</DOC>
<DOC>
<DOCNO> 119356 </DOCNO>
Clusters AgeS Experiment. RR Lyr Variables in the Globular Cluster NGC


  We present V and B-band CCD photometry of 35 RR Lyr stars in the southern
hemisphere globular cluster NGC 6362. Fourier decomposition of the light curves
was used to estimate the basic properties of these variables. From the analysis
of the RRc stars we obtain a mean mass of M=0.531+/-0.014 $M_\odot$, luminosity
log L=1.656+/-0.006, effective temperature Teff=7429+/-20, and helium abundance
Y=0.292+/-0.002. The mean values of the absolute magnitude, metallicity (on
Jurcsik's scale) and effective temperature for 14 RRab stars with "regular"
light curves are: M_V=0.86+/-0.01, [Fe/H]=-0.93+/-0.04 and Teff=6555+/-25,
respectively. From the B-V colors, periods and metallicities of the RRab stars
we estimate the color excess for NGC 6362 to be equal to E(B-V)=0.08+/-0.01.
Using this value we derive the colors of the blue and red edges of the
instability strip in NGC 6362 to be $(B-V)^{BE}_0=0.17$ and
$(B-V)^{RE}_0=0.43$. From the relations between the Fourier coefficients of
RRab and RRc stars and their absolute magnitudes we estimate the apparent
distance modulus to NGC 6362 to be (m-M)_V=14.46+/-0.10. From the mean value of
log L of the RRc stars we obtain 14.59+/-0.03. The V-band light curves of three
of the RRc stars exhibit changes in amplitude of over 0.1 mag on the time scale
of around one week. Near the radial 1st overtone frequency we find one or two
peaks, which strongly suggests that these variables belong to the newly
identified group of non-radial pulsating RR Lyr stars.

</DOC>
<DOC>
<DOCNO> 10488 </DOCNO>
Self-organization in populations of competing agents


  A population of heterogenous agents compeeting through a minority rule is
investigated. Agents which frequently loose are selected for evolution by
changing their strategies. The stationary composition of the population
resulting for this self-organization process is computed analytically. Results
are compared with numerical simulations of two different minority games and
other analytical treatments available in the literature.

</DOC>
<DOC>
<DOCNO> 12849 </DOCNO>
Relaxation of non-order parameter field in directed Ising systems


  We investigate the effect of initial conditions on the dynamic exponents of
the interacting monomer-monomer model with infinitely many absorbing states in
one dimension. This model exhibits a directed Ising (DI) type transition from
an active phase into an absorbing phase. In case of the directed percolation
universality class, it has been reported that the non-order parameter as well
as the order parameter exhibits critical fluctuations, relaxing algebraically
to its natural value with the same scaling exponents. We numerically confirm
that this is also valid for the DI universality class. We also observe
continuously varying dynamic exponents with a linear dependence on the
non-order parameter initial density.

</DOC>
<DOC>
<DOCNO> 117505 </DOCNO>
Testing for substructure in optical and X-ray clusters


  We present a detailed study of the morphological features of 22 rich galaxy
clusters. We systematically compare cluster images and morphological parameters
in an attempt to reliably identify possible substructure in both optical and
X-ray images. To this end, we compute moments of the surface-brightness
distribution to estimate ellipticities, center-of-mass shifts and orientations.
We find important correlations between the optical and X-ray morphological
shape parameters. Most of our clusters (17) have a good 1-to-1 correspondence
between the optical and the X-ray images and at least 9 appear to have strong
indications of substructure. This corresponds to a percentage of about 40% in
good accordance with other similar analyses. Finally, 4 out of 22 systems seem
to have distinct subclumps in the optical which are not verified in the X-ray
images, and thus are suspect of being due to optical projection effects. We
assess the significance of results using Monte Carlo simulations.

</DOC>
<DOC>
<DOCNO> 120807 </DOCNO>
Detection of a broad iron emission line and sub-millisecond


  We report results from simultaneous RossiXTE and BeppoSAX observations of the
neutron-star x-ray binary and type I X-ray burster 4U1728-34. The source was
found in a high luminosity state, L_X near 0.1 L_Edd, and quasiperiodic
oscillations were detected at 1284 +/- 6 Hz, the highest frequency ever
observed from this source. The x-ray spectrum shows a broad, FWHM = 0.8 keV,
iron K-alpha fluorescence line. We discuss interpretations of the broad line
and the quasiperiodic oscillations and how future simultaneous spectral and
timing observations can be used to test these interpretations and, potentially,
to estimate the mass of the compact object.

</DOC>
<DOC>
<DOCNO> 80620 </DOCNO>
Infrared Behavior of the Gluon Propagator on a Large Volume Lattice


  The first calculation of the gluon propagator using an order a^2 improved
action with the corresponding order a^2 improved Landau gauge fixing condition
is presented. The gluon propagator obtained from the improved action and
improved Landau gauge condition is compared with earlier unimproved results on
similar physical lattice volumes of 3.2^3 \times 6.4 fm^4. We find agreement
between the improved propagator calculated on a coarse lattice with lattice
spacing a = 0.35 fm and the unimproved propagator calculated on a fine lattice
with spacing a = 0.10 fm. This motivates us to calculate the gluon propagator
on a coarse large-volume lattice 5.6^3 \times 11.2 fm^4. The infrared behavior
of previous studies is confirmed in this work. The gluon propagator is enhanced
at intermediate momenta and suppressed at infrared momenta. Therefore the
observed infrared suppression of the Landau gauge gluon propagator is not a
finite volume effect.

</DOC>
<DOC>
<DOCNO> 9665 </DOCNO>
Peculiarities of structural changes in Pd and Pd-alloys


  It has been discovered that kinetics of structural changes in Pd and
Pd-alloys under the influence of dissolved hydrogen seems to be non-trivial. As
a rule, structural changes in these systems include correlation changes of
co-existing phases concentration and the defect structure character. These
changes have the stage character. Basic stages are: incubation period, quick
degassing, temporal stabilization and post-stabilization period. The structural
changes and phase transformation in Pd-M-H kinetics happens to be
non-monotonous (oscillating or stochastic). Such time dependence can be
observed during tens thousand hours. The hypothesis based on the ideas of
non-equilibrium dynamics and specific attributes of hydrogen interaction with
matrix defect and atoms in Pd-systems has been offered in order to explain
discovered phenomena.

</DOC>
<DOC>
<DOCNO> 71883 </DOCNO>
Fermionic current-carrying cosmic strings: zero-temperature limit and


  The equation of state for a superconducting cosmic string whose current is
due to fermionic zero modes is derived analytically in the case where the
back-reaction of the fermions to the background is neglected. It is first shown
that the zero mode fermions follow a zero temperature distribution because of
their interactions (or lack thereof) with the string-forming Higgs and gauge
fields. It is then found that the energy per unit length U and the tension T
are related to the background string mass m through the simple relation
U+T=2m*m. Cosmological consequences are briefly discussed.

</DOC>
<DOC>
<DOCNO> 9374 </DOCNO>
Transfer Matrices and Partition-Function Zeros for Antiferromagnetic


  We study the chromatic polynomials (= zero-temperature antiferromagnetic
Potts-model partition functions) P_G(q) for m \times n rectangular subsets of
the square lattice, with m \le 8 (free or periodic transverse boundary
conditions) and n arbitrary (free longitudinal boundary conditions), using a
transfer matrix in the Fortuin-Kasteleyn representation. In particular, we
extract the limiting curves of partition-function zeros when n \to\infty, which
arise from the crossing in modulus of dominant eigenvalues (Beraha-Kahane-Weiss
theorem). We also provide evidence that the Beraha numbers B_2,B_3,B_4,B_5 are
limiting points of partition-function zeros as n \to\infty whenever the strip
width m is \ge 7 (periodic transverse b.c.) or \ge 8 (free transverse b.c.).
Along the way, we prove that a noninteger Beraha number (except perhaps B_{10})
cannot be a chromatic root of any graph.

</DOC>
<DOC>
<DOCNO> 116929 </DOCNO>
Commissioning of Ih-RFQ and Ih-DTL for the Gsi High Current Linac


  The new 1.4 MeV/u front end HSI (HochStromInjektor) of the Unilac accelerates
ions with A/q ratios of up to 65 and with beam intensities in emA of up to 0.25
A/q. The maximum beam pulse power is up to 1300 kW. During the stepwise linac
commissioning from April to Septem-ber 1999 the beam behind of each cavity was
analysed within two weeks. A very stable Ar1+ beam out of a vol-ume plasma
source MUCIS was used mainly. The meas-ured norm. 80 % emittance areas around
0.45 pi mm mrad are close to the results from beam simulations. Up to 80 % of
the design intensity at the linac exit were achieved. In February 2000 an U4+
beam from the MEVVA source was accelerated for the first time.

</DOC>
<DOC>
<DOCNO> 151760 </DOCNO>
String propagation near Kaluza-Klein black holes: an analytical and


  This paper presents a detailed investigation of the motion of a string near a
Kaluza-Klein black hole, using the null string expansion. The zeroth-order
string equations of motion are set up separately for electrically and
magnetically charged black hole backgrounds. The case of a string falling
head-on into the black hole is considered in detail. The equations reduce to
quadratures for a magnetically charged hole, while they are amenable to
numerical solution for an electrically charged black hole. The Kaluza-Klein
radius seen by the string as it approaches the black hole decreases in the
magnetic case and increases in the electric case. For magnetic backgrounds,
analytical solutions can be obtained in terms of elliptical integrals. These
reduce to elementary functions in special cases, including that of the
well-known Pollard-Gross-Perry-Sorkin monopole. Here the string exhibits
decelerated descent into the black hole. The results in the authors' earlier
papers are substantiated here by presenting a detailed analysis. A preliminary
analysis of first-order perturbations is also presented, and it is shown that
the invariant string length receives a nonzero contribution in the first order.

</DOC>
<DOC>
<DOCNO> 70147 </DOCNO>
Filter for strangeness in J^{PC} exotic four-quark states


  Symmetrization selection rules for the decay of four-quark states to two J=0
mesons are analysed in a non - field theoretic context with isospin symmetry.
The OZI allowed decay of an isoscalar J^PC = (1,3,...)^{-+} exotic state to
eta' eta or f_0' f_0 is only allowed for four-quark components of the state
containing one s sbar pair, providing a filter for strangeness content in these
states. Decays of four-quark a_0 states are narrower than otherwise expected.
If the experimentally observed 1^{-+} enhancement in eta pi is resonant, it is
qualitatively in agreement with being a four-quark state.

</DOC>
<DOC>
<DOCNO> 13557 </DOCNO>
Unified thoery of strongly correlated electron systems


  In framework of eigen-functional bosonization method, we introduce an
imaginary phase field to uniquely represent electron correlation, and
demonstrate that the Landau Fermi liquid theory and the Tomonaga-Luttinger
liquid theory can be unified. It is very clear in this framework that the
Tomonaga-Luttinger liquid behavior of one-dimensional interacting electron
gases originates from their Fermi structure, and the non-Landau-Fermi liquid
behavior of 2D interacting electron gases is induced by the long-range electron
interaction, while 3D interacting electron gases generally show the Landau
Fermi liquid behavior.

</DOC>
<DOC>
<DOCNO> 9832 </DOCNO>
Exact solution of stochastic directed sandpile model


  We introduce and analytically solve a directed sandpile model with stochastic
toppling rules. The model clearly belongs to a different universality class
from its counterpart with deterministic toppling rules, previously solved by
Dhar and Ramaswamy. The critical exponents are D_||=7/4, \tau=10/7 in two
dimensions and D_||=3/2, \tau=4/3 in one dimension. The upper critical
dimension of the model is three, at which the exponents apart from logarithmic
corrections reach their mean-field values D_||=2, \tau=3/2.

</DOC>
<DOC>
<DOCNO> 170682 </DOCNO>
Local filtering operations on two qubits


  We consider one single copy of a mixed state of two qubits and investigate
how its entanglement changes under local quantum operations and classical
communications (LQCC) of the type $\rho'\sim (A\otimes B)\rho(A\otimes
B)^{\dagger}$. We consider a real matrix parameterization of the set of density
matrices and show that these LQCC operations correspond to left and right
multiplication by a Lorentz matrix, followed by normalization. A constructive
way of bringing this matrix into a normal form is derived. This allows us to
calculate explicitly the optimal local filterin operations for concentrating
entanglement. Furthermore we give a complete characterization of the mixed
states that can be purified arbitrary close to a Bell state. Finally we obtain
a new way of calculating the entanglement of formation.

</DOC>
<DOC>
<DOCNO> 121089 </DOCNO>
Third-dredge-up oxygen in planetary nebulae


  The planetary nebulae He 2-436 and Wray 16-423 in the Sagittarius dwarf
galaxy appear to result from nearly twin stars, except that third-dredge-up
carbon is more abundant in He 2-436. A thorough photoionization-model analysis
implies that ratios Ne/O, S/O and Ar/O are significantly smaller in He 2-436,
indicative of third-dredge-up oxygen enrichment. The enrichment of oxygen with
respect to carbon is (7 +/- 4)%. Excess nitrogen in Wray 16-423 suggests third
dredge-up of late CN-cycle products even in these low-mass,
intermediate-metallicity stars.

</DOC>
<DOC>
<DOCNO> 178396 </DOCNO>
Collective modes in asymmetric nuclei


  The collective motion of a finite nuclear system is investigated by numerical
simulation and by linear response theory. Using a pseudo-particle simulation
technique we analyze the giant resonances with a multipole decomposition
scheme. We examine the energy and the damping of different giant collective
modes and obtain the dependence of these quantities on the proton-neutron
ratio. ...(abbreviated) Alternatively the giant collective modes in asymmetric
nuclear matter are investigated within linear response theory including the
collisional correlations via a dynamic relaxation time approximation. For a
multicomponent system we derive a coupled dispersion relation and show that two
sources of coupling appear: (i) a coupling of isoscalar and isovector modes due
to the action of different mean-fields and (ii) an explicit new coupling in
asymmetric matter due to collisional interaction. We show that the latter is
responsible for a new mode arising besides isovector and isoscalar
modes...(abbreviated) Collective motion beyond the linear regime is
demonstrated for the example of large-amplitude isoscalar giant octupole
excitations in finite nuclear systems. Depending on the initial conditions we
observe either clear octupole modes or over-damped octupole modes which decay
immediately into quadrupole ones. This dependence on initial correlations
represents a behaviour beyond linear response.

</DOC>
<DOC>
<DOCNO> 151842 </DOCNO>
Quantum dilatonic gravity in d = 2,4 and 5 dimensions


  We review (mainly) quantum effects in the theories where gravity sector is
described by metric and dilaton. The one-loop effective action for dilatonic
gravity in two and four dimensions is evaluated. Renormalization group
equations are constructed. The conformal anomaly and induced effective action
for 2d and 4d dilaton coupled theories are found. It is applied to study of
quantum aspects of black hole thermodynamics, like calculation of Hawking
radiation and quantum corrections to black hole parameters and investigation of
quantum instability for such objects with multiple horizons. The use of above
effective action in the construction of non-singular cosmological models in
Einstein or Brans-Dicke (super)gravity and investigation of induced wormholes
in supersymmetric Yang-Mills theory are given.
  5d dilatonic gravity (bosonic sector of compactified IIB supergravity) is
discussed in connection with bulk/boundary (or AdS/CFT) correspondence. Running
gauge coupling and quark-antiquark potential for boundary gauge theory at zero
or non-zero temperature are calculated from d=5 dilatonic Anti-de Sitter-like
background solution which represents Anti-de Sitter black hole for periodic
time.

</DOC>
<DOC>
<DOCNO> 84360 </DOCNO>
A New Way to Make Waves


  I describe a new algorithm for solving nonlinear wave equations. In this
approach, evolution takes place on characteristic hypersurfaces. The algorithm
is directly applicable to electromagnetic, Yang-Mills and gravitational fields
and other systems described by second differential order hyperbolic equations.
The basic ideas should also be applicable to hydrodynamics. It is an especially
accurate and efficient way for simulating waves in regions where the
characteristics are well behaved. A prime application of the algorithm is to
Cauchy-characteristic matching, in which this new approach is matched to a
standard Cauchy evolution to obtain a global solution. In a model problem of a
nonlinear wave, this proves to be more accurate and efficient than any other
present method of assigning Cauchy outer boundary conditions. The approach was
developed to compute the gravitational wave signal produced by collisions of
two black holes. An application to colliding black holes is presented.

</DOC>
<DOC>
<DOCNO> 69397 </DOCNO>
Brane Gases in the Early Universe


  Over the past decade it has become clear that fundamental strings are not the
only fundamental degrees of freedom in string theory. D-branes are also part of
the spectrum of fundamental states. In this paper we explore some possible
effects of D-branes on early Universe string cosmology, starting with two key
assumptions: firstly that the initial state of the Universe corresponded to a
dense, hot gas in which all degrees of freedom were in thermal equilibrium, and
secondly that the topology of the background space admits one-cycles. We argue
by t-duality that in this context the cosmological singularities are not
present. We derive the equation of state of the brane gases and apply the
results to suggest that, in an expanding background, the winding modes of
fundamental strings will play the most important role at late times. In
particular, we argue that the string winding modes will only allow four
space-time dimensions to become large. The presence of brane winding modes with
$p > 1$ may lead to a hierarchy in the sizes of the extra dimensions.

</DOC>
<DOC>
<DOCNO> 116578 </DOCNO>
Interference at quantum transitions: lasing without inversion and


  An influence of nonlinear interference processes at quantum transitions under
strong resonance electromagnetic fields on absorption, amplification and
refractive indices as well as on four-wave mixing processes is investigated.
Doppler broadening of the coupled transitions, incoherent excitation,
relaxation processes, as well as power saturation processes associated with the
coupled levels are taken into account. Both closed (ground state is involved)
and open (only excited states are involved) energy level configurations are
considered. Common expressions are obtained which allow one to analyze the
optical characteristics (including gain without inversion and enhanced
refractive index at vanishing absorption) for various V, Lambda and H
configurations of interfering transitions by a simple substitution of
parameters. Similar expressions for resonant four-wave mixing in Raman
configurations are derived too. Crucial role of Doppler broadening is shown.
The theory is applied to numerical analysis of some recent and potential
experiments.

</DOC>
<DOC>
<DOCNO> 119866 </DOCNO>
The Importance of Einstein Rings


  We develop a theory of Einstein rings and demonstrate it using the infrared
Einstein ring images of the quasar host galaxies observed in PG1115+080,
B1608+656 and B1938+666. The shape of an Einstein ring accurately and
independently determines the shape of the lens potential and the shape of the
lensed host galaxy. We find that the host galaxies of PG1115+080, B1608+656 and
B1938+666 have axis ratios of 0.58+/-0.02, 0.69+/-0.02 and 0.62+/-0.15
including the uncertainties in the lens models. The Einstein rings break the
degeneracies in the mass distributions or Hubble constants inferred from
observations of gravitational lenses. In particular, the Einstein ring in
PG1115+080 rules out the centrally concentrated mass distributions that lead to
a high Hubble constant (H_0>60 km/s Mpc) given the measured time delays. Deep,
detailed observations of Einstein rings will be revolutionary for constraining
mass models and determining the Hubble constant from time delay measurements.

</DOC>
<DOC>
<DOCNO> 122796 </DOCNO>
Escape in Hill's Problem


  This didactic paper is motivated by the problem of understanding how stars
escape from globular star clusters. One formulation of this problem is known,
in dynamical astronomy, as Hill's problem. Originally intended as a model for
the motion of the moon around the earth with perturbations by the sun, with
simple modifications it also serves as a model for the motion of a star in a
star cluster with perturbations by the galaxy.
  The paper includes introductory sections on the derivation of the equations
of motion of Hill's problem, their elementary properties, and extensions to
deal with non-point masses and non-circular orbits. We then show how the rate
of escape may be calculated numerically and estimated theoretically, and
discuss how this simple picture is modified if the stars in a cluster are also
undergoing two-body relaxation. Finally we introduce some established ideas for
obtaining the distribution of escape times.

</DOC>
<DOC>
<DOCNO> 9730 </DOCNO>
Ground State Entropy of the Potts Antiferromagnet on Strips of the


  We present exact solutions for the zero-temperature partition function
(chromatic polynomial $P$) and the ground state degeneracy per site $W$ (=
exponent of the ground-state entropy) for the $q$-state Potts antiferromagnet
on strips of the square lattice of width $L_y$ vertices and arbitrarily great
length $L_x$ vertices. The specific solutions are for (a) $L_y=4$,
$(FBC_y,PBC_x)$ (cyclic); (b) $L_y=4$, $(FBC_y,TPBC_x)$ (M\"obius); (c)
$L_y=5,6$, $(PBC_y,FBC_x)$ (cylindrical); and (d) $L_y=5$, $(FBC_y,FBC_x)$
(open), where $FBC$, $PBC$, and $TPBC$ denote free, periodic, and twisted
periodic boundary conditions, respectively. In the $L_x \to \infty$ limit of
each strip we discuss the analytic structure of $W$ in the complex $q$ plane.
The respective $W$ functions are evaluated numerically for various values of
$q$. Several inferences are presented for the chromatic polynomials and
analytic structure of $W$ for lattice strips with arbitrarily great $L_y$. The
absence of a nonpathological $L_x \to \infty$ limit for real nonintegral $q$ in
the interval $0 < q < 3$ ($0 < q < 4$) for strips of the square (triangular)
lattice is discussed.

</DOC>
<DOC>
<DOCNO> 71249 </DOCNO>
Strange quark matter within the Nambu-Jona-Lasinio model


  Equation of state of baryon rich quark matter is studied within the SU(3)
Nambu-Jona-Lasinio model with flavour mixing interaction. Possible bound states
(strangelets) and chiral phase transitions in this matter are investigated at
various values of strangeness fraction S/3B. The model predictions are very
sensitive to the ratio of vector (Gv) and scalar (Gs) coupling constants. At
Gv/Gs=0.5 and zero temperature the maximum binding energy (about 15 MeV per
baryon) takes place when strangeness fraction is about 0.4. Such strangelets
are negatively charged and have typical life times of the order of 100 ns.
Calculations are carried out also at finite temperatures. They show that bound
states exist up to temperatures of about 15 MeV. The model predicts a first
order chiral phase transition at finite baryon densities. The parameters of
this phase transition are calculated as function of strangeness fraction.

</DOC>
<DOC>
<DOCNO> 101876 </DOCNO>
Measured creatures


  Using forcing with measured creatures we build a universe of set theory in
which:
  (a) every sup-measurable function f:RxR-->R is measurable, and
  (b) every function f:R-->R is continuous on a non-measurable set.
  This answers a question of Balcerzak, Ciesielski and Kharazishvili and von
Weizsacker's problem (see Fremlin's list of problems).

</DOC>
<DOC>
<DOCNO> 81002 </DOCNO>
Brane Vacuum as Chain of Rotators


  We analyse the noncommutative U(1) sigma model, which arises from the vacuum
dynamics of the noncommutative charged tachyonic field. The sector of
``spherically symmetric'' excitations of the model is equivalent to a chain of
rotators. Classical solutions for this model are found, which are static and
``spherically symmetric'' in noncommutative spatial dimensions. The limit of
small noncommutativity reveals the presence of Polyakov vortices in the model.
A generalisation of the model to q-deformed space, which may serve as a
regularisation of the non-deformed model is also considered.

</DOC>
<DOC>
<DOCNO> 70588 </DOCNO>
Estimate of the Three-Loop MS bar Contribution to sigma(W_L^+ W_L^- -->


  The three-loop contribution to the MS bar single-Higgs-doublet standard-model
cross-section $\sigma(W_L^+ W_L^- \to Z_L Z_L)$ at s = (5M_H)^2 is estimated
via least-squares matching of the asymptotic Pade-approximant prediction of the
next order term, a procedure that has been previously applied to QCD
corrections to correlation functions and decay amplitudes. In contrast to these
prior applications, the expansion parameter for the W_L^+ W_L^- \to Z_L Z_L
process is the non-asymptotically-free quartic scalar-field coupling of the
standard model, suggesting that the least-squares matching be performed over
the "infrared" mu^2 <= s region of the scale parameter. All three coefficients
of logarithms within the three-loop term obtained by such matching are found to
be within 6.6% relative error of their true values, as determined via
renormalization-group methods. Surprisingly, almost identical results are
obtained by performing the least squares matching over the mu^2 >= s region.

</DOC>
<DOC>
<DOCNO> 99446 </DOCNO>
Bernstein-Gelfand-Gelfand sequences


  This paper is devoted to the study of geometric structures modeled on
homogeneous spaces G/P, where G is a real or complex semisimple Lie group and
$P\subset G$ is a parabolic subgroup. We use methods from differential geometry
and very elementary finite-dimensional representation theory to construct
sequences of invariant differential operators for such geometries, both in the
smooth and the holomorphic category. For G simple, these sequences specialize
on the homogeneous model G/P to the celebrated (generalized)
Bernstein-Gelfand-Gelfand resolutions in the holomorphic category, while in the
smooth category we get smooth analogs of these resolutions. In the case of
geometries locally isomorphic to the homogeneous model, we still get
resolutions, whose cohomology is explicitly related to a twisted de Rham
cohomology. In the general (curved) case we get distinguished curved analogs of
all the invariant differential operators occurring in Bernstein-Gelfand-Gelfand
resolutions (and their smooth analogs).
  On the way to these results, a significant part of the general theory of
geometrical structures of the type described above is presented here for the
first time.

</DOC>
<DOC>
<DOCNO> 120301 </DOCNO>
Detection and Measurement of Parsec-Scale Circular Polarization in Four


  We present five epochs of 15 GHz VLBA observations of 13 AGN. These
observations were specially calibrated to detect parsec scale circular
polarization and our calibration techniques are discussed and analyzed in
detail. We obtained reliable detections of parsec scale circular polarization
in the radio jets of 4 AGN: 3C84, PKS 0528+134, 3C273, and 3C279. For each of
these objects our detections are at the level of ~ 0.3-1% local fractional
circular polarization. Our observations are consistent across multiple epochs
(and different calibration techniques) in the sign and magnitude of the
circular polarization observed. 3C273 and 3C279 both undergo core outbursts
during our observations and changes in the circular polarization of both
sources are correlated with these outbursts. In general, we observe the
circular polarization to be nearly coincident with the strong VLBI cores of
these objects; however, in 3C84 the circular polarization is located a full
milli-arcsecond south of the source peak, and in the 1996.73 epoch of 3C273 the
circular polarization is predominately associated with the newly emerging jet
component. Circular polarization may be produced as an intrinsic component of
synchrotron radiation or by the Faraday conversion of linear to circular
polarization. Our single frequency observations do not easily distinguish
between these possible mechanisms, but independent of mechanism, the remarkable
consistency across epoch of the sign of the observed circular polarization
suggests the existence of a long term, stable, uni-directional magnetic field.
Single dish observations of 3C273 and 3C279 at 8 GHz by Hodge and Aller suggest
that this stability may persist for decades in our frame of observation.

</DOC>
<DOC>
<DOCNO> 152383 </DOCNO>
The Emergence of Localized Gravity


  We explore physics on the boundary of a Randall-Sundrum type model when the
brane tension is slightly sub-critical. We calculate the masses of the
Kaluza-Klein decomposition of the graviton and use a toy model to show how
localized gravity emerges as the brane tension becomes critical. Finally, we
discuss some aspects of the boundary conformal field theory and the AdS/CFT
correspondence.

</DOC>
<DOC>
<DOCNO> 68004 </DOCNO>
Top Spin and Experimental Tests


  We examine pair mass dependence near threshold as a means to measure the spin
of the top quark in hadron collisions, and we discuss the possibility that a
top squark signal could be hidden among the top events.

</DOC>
<DOC>
<DOCNO> 71066 </DOCNO>
The Relativistic N-body Problem in a Separable Two-Body Basis


  We use Dirac's constraint dynamics to obtain a Hamiltonian formulation of the
relativistic N-body problem in a separable two-body basis in which the
particles interact pair-wise through scalar and vector interactions. The
resultant N-body Hamiltonian is relativistically covariant. It can be easily
separated in terms of the center-of-mass and the relative motion of any
two-body subsystem. It can also be separated into an unperturbed Hamiltonian
with a residual interaction. In a system of two-body composite particles, the
solutions of the unperturbed Hamiltonian are relativistic two-body internal
states, each of which can be obtained by solving a relativistic
Schr\"odinger-like equation. The resultant two-body wave functions can be used
as basis states to evaluate reaction matrix elements in the general N-body
problem. We prove a relativistic version of the post-prior equivalence which
guarantees a unique evaluation of the reaction matrix element, independent of
the ways of separating the Hamiltonian into unperturbed and residual
interactions. Since an arbitrary reaction matrix element involves composite
particles in motion, we show explicitly how such matrix elements can be
evaluated in terms of the wave functions of the composite particles and the
relevant Lorentz transformations.

</DOC>
<DOC>
<DOCNO> 117576 </DOCNO>
Warm Absorbers in Active Galactic Nuclei


  We first provide a review of the properties of warm absorbers concentrating
on what we have learned from ROSAT and ASCA. This includes dusty and dust-free
warm absorbers, non-X-ray emission and absorption features of warm absorbers,
and the possible warm absorber interpretation of the peculiar 1.1 keV features.
  We then discuss facets of warm absorbers by a more detailed investigation of
individual objects: In a first part, we discuss several candidates for dusty
warm absorbers. In a second part, we review and extend our earlier study of a
possible relation between warm absorber and CLR in NGC 4051, and confirm that
both components are of different origin (the observed coronal lines are
underpredicted by the models, the warm absorber is too highly ionized). We then
suggest that a potential overprediction of these lines in more lowly ionized
absorbers can be avoided if these warm absorbers are dusty. In a third part, we
present first results of an analysis of a deep ROSAT PSPC observation of the
quasar MR2251-178, the first one discovered to host a warm absorber. Finally,
we summarize our scrutiny under which conditions a warm absorber could account
for the dramatic spectral variability of the Narrow-line Seyfert 1 galaxy
RXJ0134-4258.

</DOC>
<DOC>
<DOCNO> 10485 </DOCNO>
Theory of Decoupling in the Mixed Phase of Extremely Type-II Layered


  The mixed phase of extremely type-II layered superconductors in perpendicular
magnetic field is studied theoretically via the layered XY model with uniform
frustration. A partial duality analysis is carried out in the weak-coupling
limit. It consistently accounts for both intra-layer (pancake) and inter-layer
(Josephson) vortex excitations. The main conclusion reached is that
dislocations of the two-dimensional (2D) vortex lattices within layers drive a
unique second-order melting transition at high perpendicular fields between a
low-temperature superconducting phase that displays a Josephson effect and a
high-temperature ``normal'' phase that displays no Josephson effect. The former
state is best described by weakly coupled 2D vortex lattices, while the latter
state is best characterized by a decoupled vortex liquid. It is further argued
on the basis of the duality analysis that the second-order melting transition
converts itself into a first-order one as the perpendicular field is lowered
and approaches the dimensional cross-over scale. The resulting critical
endpoint potentially accounts for the same phenomenon that is observed in the
mixed phase of clean high-temperature superconductors.

</DOC>
<DOC>
<DOCNO> 169796 </DOCNO>
Communication Capacity of Quantum Computation


  By considering quantum computation as a communication process, we relate its
efficiency to a communication capacity. This formalism allows us to rederive
lower bounds on the complexity of search algorithms. It also enables us to link
the mixedness of a quantum computer to its efficiency. We discuss the
implications of our results for quantum measurement.

</DOC>
<DOC>
<DOCNO> 116363 </DOCNO>
Gauge symmetry, left-right asymmetry and atom-antiatom systems:


  We show that Coulomb's law is a universal molecular function. Charge
inversion in one atom (handedness or chirality) generates a switch from
atom-atom to atom-antiatom systems. this switch reduces the 10 term Hamiltonian
for 4-particle systems to only 1 or 2 terms. This reduced parity adapted
Hamiltonian accounts for observed PECs for atom-atom systems (results for 9
bonds are given). Hydrogen-antihydrogen reactions, feasible in the near future,
will produce a normal H(2) molecule, which would solve the problem about the
existence of anti-matter.

</DOC>
<DOC>
<DOCNO> 68897 </DOCNO>
Hadron Structure Functions within a Chiral Quark Model


  We outline a consistent regularization procedure to compute hadron structure
functions within bosonized chiral quark models. We impose the Pauli--Villars
scheme, which reproduces the chiral anomaly, to regularize the bosonized
action. We derive the Compton amplitude from this action and utilize the
Bjorken limit to extract structure functions that are consistent with the
scaling laws and sum rules of deep inelastic scattering.

</DOC>
<DOC>
<DOCNO> 83366 </DOCNO>
Using a Probabilistic Class-Based Lexicon for Lexical Ambiguity


  This paper presents the use of probabilistic class-based lexica for
disambiguation in target-word selection. Our method employs minimal but precise
contextual information for disambiguation. That is, only information provided
by the target-verb, enriched by the condensed information of a probabilistic
class-based lexicon, is used. Induction of classes and fine-tuning to verbal
arguments is done in an unsupervised manner by EM-based clustering techniques.
The method shows promising results in an evaluation on real-world translations.

</DOC>
<DOC>
<DOCNO> 102619 </DOCNO>
Multipliers and dual operator algebras


  In a previous paper we showed how the main theorems characterizing operator
algebras and operator modules, fit neatly into the framework of the
`noncommutative Shilov boundary', and more particularly via the left multiplier
operator algebra of an operator space. As well as giving new characterization
theorems, the approach of that paper allowed many of the hypotheses of the
earlier theorems to be eliminated. Recent progress of the author with Effros
and Zarikian now enables weak*-versions of these characterization theorems. For
example, we prove a result analogous to Sakai's famous characterization of von
Neumann algebras as the C*-algebras with predual, namely, that the
$\sigma$-weakly closed unital (not-necessarily-selfadjoint) subalgebras of
$B(H)$ for a Hilbert space $H$, are exactly the unital operator algebras which
possess an operator space predual. This removes one of the hypotheses from an
earlier characterization due to Le Merdy. We also show that the multiplier
operator algebras of dual operator spaces are dual operator algebras. Using
this we refine several known results characterizing dual operator modules.

</DOC>
<DOC>
<DOCNO> 119389 </DOCNO>
2MASS Extended Sources in the Zone of Avoidance


  The Two Micron All Sky Survey (2MASS) is now underway and will provide a
complete census of galaxies as faint as 13.5 mag (3 mJy) at 2.2 microns for
most of the sky, and ~12.1 mag (10 mJy) for regions veiled by the Milky Way.
This census has already discovered nearby galaxies previously hidden behind our
Galaxy, and will allow delineation of large-scale structures in the
distribution of galaxies across the whole sky. Here we report the detection and
discovery of new extended sources from this survey for fields incorporating the
Galactic plane at longitudes between 40 and 70 deg. The area-normalized
detection rate is ~1-2 galaxies per deg^2 brighter than 12.1 mag (10 mJy),
roughly constant with Galactic latitude throughout the "Zone of Avoidance", of
which 85-95% are newly discovered sources. In conjunction with the deep HI
surveys, 2MASS will greatly increase the current census of galaxies hidden
behind the Milky Way.

</DOC>
<DOC>
<DOCNO> 71467 </DOCNO>
QED in the Worldline Formalism


  A survey is given of applications of the ``string-inspired'' worldline
formalism to the computation of amplitudes and effective actions in QED.

</DOC>
<DOC>
<DOCNO> 11604 </DOCNO>
About common physical nature of divergence and interference


  The difference of actions between nearly lying unstable ``8'' and ``0'' like
trajectories in two dimensions is computed by methods of chaotic dynamics. We
found it to be equal to $pY\Theta/2$, where $\Theta$ is angle between paths at
cross, $Y$ is distance between paths, and $p$ is momentum. This kind of
periodic trajectories contributes $\tau^2$ (interference) term to spectral
form-factor.

</DOC>
<DOC>
<DOCNO> 84313 </DOCNO>
Spacetime as a Feynman diagram: the connection formulation


  Spin foam models are the path integral counterparts to loop quantized
canonical theories. In the last few years several spin foam models of gravity
have been proposed, most of which live on finite simplicial lattice spacetime.
The lattice truncates the presumably infinite set of gravitational degrees of
freedom down to a finite set. Models that can accomodate an infinite set of
degrees of freedom and that are independent of any background simplicial
structure, or indeed any a priori spacetime topology, can be obtained from the
lattice models by summing them over all lattice spacetimes. Here we show that
this sum can be realized as the sum over Feynman diagrams of a quantum field
theory living on a suitable group manifold, with each Feynman diagram defining
a particular lattice spacetime. We give an explicit formula for the action of
the field theory corresponding to any given spin foam model in a wide class
which includes several gravity models. Such a field theory was recently found
for a particular gravity model [De Pietri et al, hep-th/9907154]. Our work
generalizes this result as well as Boulatov's and Ooguri's models of three and
four dimensional topological field theories, and ultimately the old matrix
models of two dimensional systems with dynamical topology. A first version of
our result has appeared in a companion paper [gr-qc\0002083]: here we present a
new and more detailed derivation based on the connection formulation of the
spin foam models.

</DOC>
<DOC>
<DOCNO> 121666 </DOCNO>
Dust in active nuclei. II. Powder or gravel?


  In a companion paper, Maiolino et al. (2000) presented various observational
evidences for "anomalous" dust properties in the circumnuclear region of AGNs
and, in particular, the reduced E(B-V)/N_H and Av/N_H ratios, the absence of
the silicate absorption feature in mid-IR spectra of Sy2s and the absence of
the carbon dip in UV spectra of reddened Sy1s. In this paper we discuss various
explanations for these facts.
  The observational constraints favor a scenario where coagulation, catalyzed
by the high densities in the circumnuclear region, yields to the formation of
large grains. The resulting extinction curve is featureless, flatter than
Galactic and the E(B-V)/N_H and Av/N_H ratios are significantly reduced. These
results should warn about an unappropriate use of the standard Galactic
extinction curve and Av/N_H ratio when dealing with the extreme gas conditions
typical of the circumnuclear clouds of AGNs.
  We also investigated alternative scenarios for the observed anomalous
properties of dust in AGNs. Some of these scenarios might explain some of the
observed properties for a few objects, but they generally fail to account for
all of the observational constraints obtained for the large sample of AGNs
studied in these works.

</DOC>
<DOC>
<DOCNO> 152075 </DOCNO>
Hamiltonian Solution of the Schwinger Model with Compact U(1)


  The complete exact solution of the Schwinger model with compact gauge group
U(1), in the Hamiltonian approach, is presented . The compactification is
imposed by demanding that the only surviving true electromagnetic degree of
freedom has angular character. Not surprinsingly, this topological condition
defines a version of the Schwinger model which is different from the standard
one, where $c$ takes values on the line . The main consequences are: the
spectra of the zero modes is not degenerated and does not correspond to the
equally spaced harmonic oscillator, both the electric charge and a modified
gauge invariant chiral charge are conserved (nevertheless, the axial-current
anomaly is still present) and, finally, there is no need to introduce a
$\theta$-vacuum. A comparison with the results of the standard Schwinger model
is pointed out along the text.

</DOC>
<DOC>
<DOCNO> 178699 </DOCNO>
Critical Review Of Quark Gluon Plasma Signals


  Compelling evidence for a new form of matter has been claimed to be formed in
Pb+Pb collisions at SPS. We critically review two suggested signatures for this
new state of matter: First the suppression of the J/$\Psi$, which should be
strongly suppressed in the QGP by two different mechanisms, the color-screening
and the QCD-photoeffect. Secondly the measured particle, in particular strange
hadronic, ratios might signal the freeze-out from a quark-gluon phase.

</DOC>
<DOC>
<DOCNO> 68789 </DOCNO>
The PSI np data and their effect on the charge Pi-N-N coupling constant


  Differential cross sections of elastic neutron-proton scattering have been
measured for the energy range from 200 MeV to 580 MeV. The angular interval for
the detection of the recoiling proton ranges up to 48 degree in the laboratory
system. This corresponds to an interval of the scattering angle from 80 degree
to 180 degree in the centre-of-mass system. For absolute normalization the
simultaneously measured np --> d Pi^o reaction was used above 280 MeV. The
charged Pi-NN coupling constant has been determined to f^2_{Pi-n-p} =
0.076+-0.001.

</DOC>
<DOC>
<DOCNO> 71195 </DOCNO>
Transport coefficients in high temperature gauge theories: (I)


  Leading-log results are derived for the shear viscosity, electrical
conductivity, and flavor diffusion constants in both Abelian and non-Abelian
high temperature gauge theories with various matter field content.

</DOC>
<DOC>
<DOCNO> 9136 </DOCNO>
How native state topology affects the folding of Dihydrofolate Reductase


  The overall structure of the transition state and intermediate ensembles
experimentally observed for Dihydrofolate Reductase and Interleukin-1beta can
be obtained utilizing simplified models which have almost no energetic
frustration. The predictive power of these models suggest that, even for these
very large proteins with completely different folding mechanisms and functions,
real protein sequences are sufficiently well designed and much of the
structural heterogeneity observed in the intermediates and the transition state
ensembles is determined by topological effects.

</DOC>
<DOC>
<DOCNO> 85395 </DOCNO>
Uniqueness of the asymptotic AdS3 geometry


  We explicitly show that in (2+1) dimensions the general solution of the
Einstein equations with negative cosmological constant on a neigbourhood of
timelike spatial infinity can be obtained from BTZ metrics by coordinate
transformations corresponding geometrically to deformations of their spatial
infinity surface. Thus, whatever the topology and geometry of the bulk, the
metric on the timelike extremities is BTZ.

</DOC>
<DOC>
<DOCNO> 117406 </DOCNO>
The Dark Matter Distribution in Disk Galaxies


  We use high-quality optical rotation curves of 9 low-luminosity disk galaxies
to obtain the velocity profile of the surrounding dark matter halos. We find
that they increase linearly with radius at least out to the stellar disk edge,
implying that, over the entire region where the stars reside, the density of
the dark halo is constant. The properties of the halo mass structure found are
similar to that claimed for a number of dwarf and low surface brightness
galaxies, but provide a more substantial evidence of the discrepancy between
the halo mass distribution predicted in standard cold dark matter scenario and
those actually detected around galaxies. We find that the density profile
proposed by Burkert (1995) reproduces the halo rotation curves, with halo
central densities and core radii scaling as $\rho_0 \propto r_0^{-2/3}$.

</DOC>
<DOC>
<DOCNO> 69850 </DOCNO>
Observable contributions of new exotic quarks to quark mixing


  Models with new vector-like quarks can produce observable quark mixing
effects which are forbidden in the Standard Model. We classify all such models
and write down the effective Lagrangian that results from integrating out the
new quarks. We study the relations between neutral and charged currents and
discuss how to distinguish among the different possibilities.

</DOC>
<DOC>
<DOCNO> 116676 </DOCNO>
A time series model of CDS sequences in complete genome


  A time series model of CDS sequences in complete genome is proposed.
  A map of DNA sequence to integer sequence is given. The correlation
dimensions and Hurst exponents of CDS sequences in complete genome of bacteria
are calculated. Using the average of correlation dimensions, some interesting
results are obtained.

</DOC>
<DOC>
<DOCNO> 85021 </DOCNO>
Trans-Planckian Modes, Back-Reaction, and the Hawking Process


  Hawking's prediction of black-hole evaporation depends on the application of
known physics to fantastically high energies -- well beyond the Planck scale.
Here, I show that before these extreme regimes are reached, another physical
effect will intervene: the quantum backreaction on the collapsing matter and
its effect on the geometry through which the quantum fields propagate. These
effects are estimated by a simple thought experiment. When this is done, it
appears that there are no matrix elements allowing the emission of Hawking
quanta: black holes do not radiate.

</DOC>
<DOC>
<DOCNO> 71930 </DOCNO>
GRAPE-Dilepton (version1.1), A Generator for Dilepton Production in ep


  GRAPE-Dilepton is a Monte Carlo event generator for dilepton production in ep
collisions. The cross-section calculation is based on the exact matrix elements
in the electroweak theory at tree level. The dilepton productions via $\gamma
\gamma$, $\gamma Z^0$, $Z^0 Z^0$ collisions and via photon internal conversion
are taken into account. In addition, the effects of the $Z^0$ on/off-shell
production are also included. The relevant Feynman amplitudes are generated by
the automatic calculation system GRACE. The calculation of the proton vertex
covers the whole kinematical region. This generator has an interface to PYTHIA
and SOPHIA to obtain complete hadronic final states.

</DOC>
<DOC>
<DOCNO> 84481 </DOCNO>
Ekman layers and the damping of inertial r-modes in a spherical shell:


  Recently, eigenmodes of rotating fluids, namely inertial modes, have received
much attention in relation to their destabilization when coupled to
gravitational radiation within neutron stars. However, these modes have been
known for a long time by fluid dynamicists. We give a short account of their
history and review our present understanding of their properties. Considering
the case of a spherical container, we then give the exact solution of the
boundary (Ekman) layer flow associated with inertial r-modes and show that
previous estimations all underestimated the dissipation by these layers. We
also show that the presence of an inner core has little influence on this
dissipation. As a conclusion, we compute the window of instability in the
Temperature/rotation plane for a crusted neutron star when it is modeled by an
incompressible fluid.

</DOC>
<DOC>
<DOCNO> 11018 </DOCNO>
Condensates beyond mean field theory: quantum backreaction as


  We propose an experiment to measure the slow log(N) convergence to mean-field
theory (MFT) around a dynamical instability. Using a density matrix formalism,
we derive equations of motion which go beyond MFT and provide accurate
predictions for the quantum break-time. The leading quantum corrections appear
as decoherence of the reduced single-particle quantum state.

</DOC>
<DOC>
<DOCNO> 68697 </DOCNO>
Features of Nucleosynthesis and Neutrino Emission from Collapsars


  In this study we present two indicators that will reflect the difference
between collapsars and normal collapse-driven supernovae. They are products of
explosive nucleosynthesis and neutrino emission. In the collapsar model, it is
natural to consider that the product of explosive nucleosynthesis depends on
the zenith angle because the system becomes highly asymmetric in order to
generate a fire ball. We also consider the detectability of the HNRs which is
located nearby our Galaxy. As a result, the number of the HNRs is estimated to
be 5 $\times$ ($10^2$ -- $10^{-3}$), whose chemical composition can be
spatially resolved. Using the optimistic estimate, more HNRs will be found and
it will be possible to discuss on the chemical composition statistically. As
for the energy spectrums of neutrinos, they are not thermalized in a collapsar
because the density of the accretion disk is much lower than that of a neutron
star. The energy spectrums of (anti-)electron neutrinos from hypernovae will be
mainly determined by the process of electron (positron) capture on free proton
(neutron). It is also noted that high energy tail is not dumped in the case of
hypernovae because the density of emitting region is low. Total energy of
neutrino from hypernovae will depend on a lot of physical parameters such as
total accreting mass and mass accretion rate, which are quite contrary to the
situation of the normal collapse-driven supernovae. Therefore there will be a
large variety of total neutrino's energies among collapsars. In the case of SN
1998bw, we think that the matter around the equatorial plane might be ejected
from the system, which resulted in the formation of relatively weak jets and
faint GRB 980425.

</DOC>
<DOC>
<DOCNO> 69418 </DOCNO>
A Poincare-Covariant Parton Cascade Model for Ultrarelativistic


  We present a new cascade-type microscopic simulation of nucleus-nucleus
collisions at RHIC energies. The basic elements are partons (quarks and gluons)
moving in 8N-dimensional phase space according to Poincare-covariant dynamics.
The parton-parton scattering cross sections used in the model are computed
within perturbative QCD in the tree-level approximation. The Q^2 dependence of
the structure functions is included by an implementation of the DGLAP mechanism
suitable for a cascade, so that the number of partons is not static, but varies
in space and time as the collision of two nuclei evolves. The resulting parton
distributions are presented, and meaningful comparisons with experimental data
are discussed.

</DOC>
<DOC>
<DOCNO> 121808 </DOCNO>
The Physics of Blazar Optical Emission Regions I: Alignment of Optical


  We collected optical and near IR linear polarization data obtained over
20--30 years for a sample of 51 blazars. For each object, we calculated the
probability that the distribution of position angles was isotropic. The
distribution of these probabilities was sharply peaked, with 27 blazars showing
a probability < 15% of an isotropic distribution of position angles.
  For these 27 objects we defined a preferred position angle. For those 17 out
of 27 blazars showing a well-defined radio structure angle (jet position angle)
on VLBI scales (1--3mas), we looked at the distribution of angle differences --
the optical polarization relative to the radio position angles. This
distribution is sharply peaked, especially for the BL Lac objects, with
alignment better than 15 degrees for half the sample. Those blazars with
preferred optical position angles were much less likely to have bent jets on
1--20mas scales. These results support a shock-in-jet hypothesis for the jet
optical emission regions.

</DOC>
<DOC>
<DOCNO> 122967 </DOCNO>
The black hole mass vs bulge mass relationship in spiral galaxies


  We describe an on-going HST program aimed at determining the relationship
between the nuclear black hole mass and bulge mass in spiral galaxies. We have
selected a volume limited sample of 54 nearby spiral galaxies for which we
already have ground based emission line rotation curves, CCD surface photometry
and radio maps. We are now obtaining HST/STIS longslit observations of each of
the galaxies in the sample in order to determine the nuclear Halpha rotation
curve at high (~0.1") spatial resolution. We will use these data to measure the
unresolved dark mass concentration at the nucleus of each object. Here we show
the first results from observations of objects in the sample.

</DOC>
<DOC>
<DOCNO> 12007 </DOCNO>
A Model for Bone Strength and Osteoporotic Fractures


  Inner porous regions play a critical role in the load bearing capability of
large bones.We show that an extension of disordered elastic networks [Chung et.
al., Phys. Rev. B, {\bf 54}, 15094 (1996)] exhibits analogs of several known
mechanical features of bone. The "stress-backbones" and histograms of stress
distributions for healthy and weak networks are shown to be qualitatively
different. A hereto untested relationship between bone density and bone
strength is presented.

</DOC>
<DOC>
<DOCNO> 70432 </DOCNO>
MESON2000 Conference Summary


  This short contribution is a {\it lite} MESON2000 conference summary. As
appropriate for the 600th anniversary of the Jagellonian University, it begins
with a brief summary of the last 600 years of European history and its place in
hadron physics. Next a ``physicist chirality'' order parameter PC is
introduced. When applied to MESON2000 plenary speakers this order parameter
illustrates the separation of hadron physicists into disjoint communities. The
individual plenary talks in MESON2000 are next sorted according to the
subconference associated with each of the 36 plenary speakers. Finally, I
conclude with a previously unreported Feynman story regarding the use of models
in hadron physics.

</DOC>
<DOC>
<DOCNO> 122012 </DOCNO>
Status of VHE Astronomy c.2000


  The status of VHE Astronomy is reviewed

</DOC>
<DOC>
<DOCNO> 85112 </DOCNO>
AdS_2 Gravity as Conformally Invariant Mechanical System


  We show that two-dimensional (2D) AdS gravity induces on the spacetime
boundary a conformally invariant dynamics that can be described in terms of a
de Alfaro-Fubini-Furlan model coupled to an external source with conformal
dimension two. The external source encodes the information about the gauge
symmetries of the 2D gravity system. Alternatively, there exists a description
in terms of a mechanical system with anholonomic constraints. The considered
systems are invariant under the action of the conformal group generated by a
Virasoro algebra, which occurs also as asymptotic symmetry algebra of
two-dimensional anti-de Sitter space. We calculate the central charge of the
algebra and find perfect agreement between statistical and thermodynamical
entropy of AdS_2 black holes.

</DOC>
<DOC>
<DOCNO> 152533 </DOCNO>
Domain Wall World(s)


  Gravitational properties of domain walls in fundamental theory and their
implications for the trapping of gravity are reviewed. In particular, the
difficulties to embed gravity trapping configurations within gauged
supergravity is reviewed and the status of the domain walls obtained via the
breathing mode of sphere reduced Type IIB supergravity is presented.

</DOC>
<DOC>
<DOCNO> 100059 </DOCNO>
Products of harmonic forms and rational curves


  In general, the product of harmonic forms is not harmonic. We study the top
exterior power of harmonic two-forms on compact Kaehler manifolds. Often, it is
not harmonic. This phenomenon is related to the geometry of the manifold and to
the existence of rational curves in particular. K3 surfaces and hyperkaehler
manifolds are discussed in detail.

</DOC>
<DOC>
<DOCNO> 9615 </DOCNO>
Interplay of superconductivity with structural phases in a generalized


  The phase diagram of the t-J-V model is discussed using a 1/N expansion in
terms of X operators. It is shown that a flux phase of d-wave symmetry is
stabilized by the Coulomb interaction V at intermediate dopings and competes
with d-wave superconductivity. Since the flux wave instability is stronger than
the superconducting one optimal doping is essentially determined by the onset
of the flux phase. Below optimal doping the flux phase coexists with
superconductivity at low and exists as a pseudo gap phase at higher
temperatures. It is also found that the flux phase boundary is much less
sensitive to impurity scattering than the boundary for superconductivity in
agreement with experiments in Zn doped La-214 and (Y,Ca)-123.

</DOC>
<DOC>
<DOCNO> 169783 </DOCNO>
Derivation of Standard Treatment of Spin Addition From Probability


  In a recent paper, we introduced a new way of treating systems of compounded
angular momentum. We obtained the probability amplitudes for measurements on
the systems and used these to derive the matrix treatment of compounded spin.
However, the matrix forms are in 3- and 4- dimensional space and are therefore
entirely different from the standard forms. This raises the question of the
connection between these forms and the standard forms. In this paper, we answer
this question. We not only derive the standard matrix treatment of spin
addition - we discover a more generalized form of the theory. We apply the new
generalized theory to the singlet and triplet states arising from the addition
of the spins of two systems of spin 1/2 each. We obtain new generalized forms
of the vectors and operators for these cases, and show that they reduce to the
standard forms in the appropriate limit.

</DOC>
<DOC>
<DOCNO> 118774 </DOCNO>
Reversing type II migration: resonance trapping of a lighter giant


  We present a mechanism related to the migration of giant protoplanets
embedded in a protoplanetary disc whereby a giant protoplanet is caught up,
before having migrated all the way to the central star, by a lighter outer
giant protoplanet. This outer protoplanet may get captured into the 2:3
resonance with the more massive one, in which case the gaps that the two
planets open in the disc overlap. Two effects arise, namely a squared mass
weighted torque imbalance and an increased mass flow through the overlapping
gaps from the outer disc to the inner disc, which both play in favour of an
outwards migration. Indeed under the conditions presented here, which describe
the evolution of a pair of protoplanets respectively Jupiter and Saturn sized,
the migration is reversed, while the planets semi-major axis ratio is constant
and the eccentricities are confined to small values by the disc material. The
long-term behaviour of the system is briefly discussed, and could account for
the high eccentricities observed for the extrasolar planets with semi-major
axis a>0.2 AU.

</DOC>
<DOC>
<DOCNO> 70118 </DOCNO>
Impact of the W boson decay width on photon bremsstrahlung accompanying


  The bremsstrahlung spectrum of photons accompanying $W$ pair production
depends on the decay width of the unstable $W$ bosons. The dependence arises
from the interference between emission at different stages of the production
and decay process. We present a quantitative discussion of this effect, and
consider the implications for measurements at LEP2 and LC energies.

</DOC>
<DOC>
<DOCNO> 9572 </DOCNO>
Energy Storage in a Hamiltonian System in Partial Contact with a Heat


  To understand the mechanism allowing for the long-term storage of excess
energy in proteins, we study a Hamiltonian system consisting of several coupled
pendula in partial contact with a heat bath. It is found that energy storage is
possible when the motion of each pendulum switches between oscillatory
(vibrational) and rotational (phase-slip) modes. The storage time increases
almost exponentially to the square root of the injected energy. The relevance
of our mechanism to protein motors is discussed.

</DOC>
<DOC>
<DOCNO> 116585 </DOCNO>
The modifications of customary filtrational equation


  The usable limits of the customary and relaxational filtrational theories are
considered. The questions of applicable the locality and local thermodynamical
equilibrium principles to depict the nonstationary flows are discussed. The
experimental procedures are proposed to determine the filtrational flows
relaxation times.

</DOC>
<DOC>
<DOCNO> 121991 </DOCNO>
From Messier to Abell: 200 years of science with galaxy clusters


  I review the history of scientific research on galaxy clusters, from 1784,
the year of publication of Messier's catalogue, to 1983, the year of George O.
Abell's premature death.
  My review covers four main topics:
  1) the distribution of clusters,
  2) the cluster components,
  3) the cluster structure,
  4) the evolution of clusters.
  I consider both theoretical and observational aspects, but not technical
aspects, such as the development of new telescopes and instruments.
  In total, 529 papers are cited in this review.

</DOC>
<DOC>
<DOCNO> 152209 </DOCNO>
Boundary Effects in One-Loop Supergravity


  A brief review is presented of motivations and results in one-loop
supergravity on manifolds with boundary, whose consideration is suggested by
quantum cosmology.

</DOC>
<DOC>
<DOCNO> 10571 </DOCNO>
Thermodynamics of the low-temperature structural transition in


  The Sr concentration dependence of the structural transition from the
orthorhombic into the tetragonal low-temperature phase in rare-earth-doped (R =
Nd, Eu) La_{2-x-y}Sr_xR_yCuO_4 has been studied in detail. Independently of the
rare earth concentration the transition temperature is strongly reduced at x ~
0.05. We give a qualitative argument that the effect can be attributed to the
Coulomb repulsion between doped carriers. We find the enthalpy jump at the
low-temperature transition to scale transition temperature between the
high-temperature tetragonal and the orthorhombic phase. This effect can be
understood in terms of a Landau expansion.

</DOC>
<DOC>
<DOCNO> 150671 </DOCNO>
Confinement and screening of the Schwinger model on the Poincare half


  We discuss the confining features of the Schwinger model on the Poincare half
plane. We show that despite the fact that the expectation value of the large
Wilson loop of massless Schwinger model displays the perimeter behavior, the
system can be in confining phase due to the singularity of the metric at
horizontal axis. It is also shown that in the quenched Schwinger model, the
area dependence of the Wilson loop, in contrast to the flat case, is a not a
sign of confinement and the model has a finite energy even for large external
charges separation. The presence of dynamical fermions can not modify the
screening or the confining behavior of the system. Finally we show that in the
massive Schwinger model, the system is again in screening phase. The zero
curvature limit of the solutions is also discussed.

</DOC>
<DOC>
<DOCNO> 84103 </DOCNO>
Critical phenomena in gravitational collapse - Living Reviews


  As first discovered by Choptuik, the black hole threshold in the space of
initial data for general relativity shows both surprising structure and
surprising simplicity. Universality, power-law scaling of the black hole mass,
and scale echoing have given rise to the term ``critical phenomena''. They are
explained by the existence of exact solutions which are attractors within the
black hole threshold, that is, attractors of codimension one in phase space,
and which are typically self-similar. This review gives an introduction to the
phenomena, tries to summarize the essential features of what is happening, and
then presents extensions and applications of this basic scenario. Critical
phenomena are of interest particularly for creating surprising structure from
simple equations, and for the light they throw on cosmic censorship and the
generic dynamics of general relativity.

</DOC>
<DOC>
<DOCNO> 178850 </DOCNO>
Long- and medium-range components of the nuclear force in quark-model


  Quark-model descriptions of the nucleon-nucleon interaction contain two main
ingredients, a quark-exchange mechanism for the short-range repulsion and
meson-exchanges for the medium- and long-range parts of the interaction. We
point out the special role played by higher partial waves, and in particular
the 1F3, as a very sensitive probe for the meson-exchange part employed in
these interaction models. In particular, we show that the presently available
models fail to provide a reasonable description of higher partial waves and
indicate the reasons for this shortcoming.

</DOC>
<DOC>
<DOCNO> 9616 </DOCNO>
On the Bragg, Leibfried, and Modified Leibfried Numbers


  The Bragg, Leibfried, and modified Leibfried numbers are defined in the
context of a theory of dislocation-mediated melting, and their values are
determined from the properties of the dislocation ensemble at the melting
temperature. The approximate numerical coincidence of the Bragg and modified
Leibfried numbers is explained. The parameter K in the definition of the
modified Leibfried number is shown to be the natural logarithm of the effective
coordination number. Our analysis reveals that the Bragg number can be
considered an elemental constant, in contrast to the Leibfried and modified
Leibfried numbers.

</DOC>
<DOC>
<DOCNO> 121183 </DOCNO>
An Atlas of Burst Oscillations and Spectral Properties in 4U 1728-34


  We study correlations between the burst properties and the position in the
color-color diagram of the low mass X-ray binary 4U 1728-34 using 21 bursts
found in two data sets obtained with the Rossi X-ray Timing Explorer. Using
spectral fits we analyze the spectral evolution during the bursts and determine
the burst peak flux, temperature, rise time and fluence. Using dynamical power
spectra we study the properties of the ~363 Hz burst oscillations. We find
correlations between fluence, peak flux, the occurrence of radius expansion and
the presence of burst oscillations, and the position of the source in the
color-color diagram. The radius expansion bursts with and without burst
oscillations differ both with respect to where they occur in the color-color
diagram and in how the radius expansion takes place. We compare our results
with those of a similar study by Muno et al. (2000) for KS 1731-26. Both KS
1731-260 and 4U 1728-34 show more or less the same behavior with respect to the
dependence of the presence/absence of the burst oscillations on the position of
the source in the color-color diagram, but the dependence of most of the
spectral burst parameters on the position in the color-color diagram is clearly
different. We find that the systematic absence in 4U 1728-34 of burst
oscillations in the ``island'' state of the color-color diagram is not
explained by the bursts involving mixed H-He burning, as may be the case in KS
1731--260 (Cumming & Bildsten 2000).

</DOC>
<DOC>
<DOCNO> 85316 </DOCNO>
Non-Linear Evolution of the r-Modes in Neutron Stars


  The evolution of a neutron-star r-mode driven unstable by gravitational
radiation (GR) is studied here using numerical solutions of the full non-linear
fluid equations. The amplitude of the mode grows to order unity before strong
shocks develop which quickly damp the mode. In this simulation the star loses
about 40% of its initial angular momentum and 50% of its rotational kinetic
energy before the mode is damped. The non-linear evolution causes the fluid to
develop strong differential rotation which is concentrated near the surface and
especially near the poles of the star.

</DOC>
<DOC>
<DOCNO> 71553 </DOCNO>
Super-Hubble Nonlinear Perturbations During Inflation


  We show that the non-linear evolution of long wavelength perturbations may be
important in a wide class of inflationary scenarios. We develop a solution for
the evolution of such nonlinear perturbations which is exact to first order in
a gradient expansion. As a first application, we demonstrate that in single
field models of inflation there can be no parametric amplification of
super-Hubble modes during reheating. We consider the implications of the
solution for recent discussions of the back-reaction effect of long wavelength
perturbations on the background geometry, give a new derivation of the equation
of motion of stochastic inflation, and demonstrate that if the (generalized)
slow-rolling condition is not satisfied, then inevitably long wavelength vector
modes for gravitational fluctuations will be generated.

</DOC>
<DOC>
<DOCNO> 120899 </DOCNO>
On the 21Na(p,gamma)22Mg thermonuclear rate for 22Na production in novae


  Classical novae are potential sources of gamma-rays, like the 1.275 MeV gamma
emission following 22Na beta decay, that could be detected by appropriate
instruments on board of future satellites like INTEGRAL. It has been shown that
the production of 22Na by novae is affected by the uncertainty on the
21Na(p,gamma)22Mg rate and in particular by the unknown partial widths of the
Ex = 5.714 MeV, J^pi = 2^+, 22Mg level. To reduce these uncertainties, we
performed shell model calculations with the OXBASH code, compared the results
with available spectroscopic data and calculated the missing partial widths.
Finally, we discuss the influence of these results on the 21Na(p,gamma)22Mg
reaction rate and 22Na synthesis.

</DOC>
<DOC>
<DOCNO> 39974 </DOCNO>
Experimental Bounds on Masses and Fluxes of Nontopological Solitons


  We have re-analyzed the results of various experiments which were not
originally interested as searches for the Q-ball or the Fermi-ball. Based on
these analyses, in addition to the available data on Q-balls, we obtained
rather stringent bounds on flux, mass and typical energy scale of Q-balls as
well as Fermi-balls. In case these nontopological solitons are the main
component of the dark matter of the Galaxy, we found that only such solitons
with very large quantum numbers are allowed. We also estimate how sensitive
future experiments will be in the search for Q-balls and Fermi-balls.

</DOC>
<DOC>
<DOCNO> 119143 </DOCNO>
Shell model description of 16O(p,gamma)17F and 16O(p,p)16O reactions


  We present shell model calculations of both the structure of 17F and the
reactions 16O(p,gamma)17F, 16O(p,p)16O. We use the ZBM interaction which
provides a good description of the properties of 16O and neighbouring nuclei
and, in particular it takes account for the complicated correlations in
coexisting low-lying states of 16O.

</DOC>
<DOC>
<DOCNO> 102746 </DOCNO>
A generalised Hopf algebra for solitons


  This paper considers a generalisation of the idea of a Hopf algebra in which
a commutative ring replaces the field in the unit and counit. It is motivated
by an example from the inverse scattering formalism for solitons. We begin with
the corresponding idea for groups, where the concept of the identity is
altered.

</DOC>
<DOC>
<DOCNO> 70261 </DOCNO>
Neutrino masses and mixing with seesaw mechanism and universal breaking


  In the framework of a minimal extension of the SM, where the only additional
fields are three right-handed neutrinos, we suggest that the charged lepton,
the Dirac neutrino and the right-handed Majorana neutrino mass matrices are
all, to leading approximation, proportional to the democratic matrix. With the
further assumption that the breaking of this extended democracy is universal
for all leptonic mass matrices, a large mixing in the 2-3 sector can be
obtained and is linked to the seesaw mechanism, together with the existence of
a strong hierarchy in the masses of right-handed neutrinos. The structure of
the resulting effective mass matrix of light neutrinos is stable against the
RGE evolution, and a good fit to all solar and atmospheric neutrino data is
obtained.

</DOC>
<DOC>
<DOCNO> 150788 </DOCNO>
Raiders of the Lost AdS


  We demonstrate that under certain conditions a theory of conformal quantum
mechanics will exhibit the symmetries of two half-Virasoro algebras. We further
demonstrate the conditions under which these algebras combine to form a single
Virasoro algebra, and comment on the connection between this result and the
AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 40554 </DOCNO>
A Measurement of the Decay Asymmetry Parameters in $\Xi_{c}^{0}\to


  Using the CLEO II detector at the Cornell Electron Storage Ring we have
measured the $\Xi_c^{0}$ decay asymmetry parameter in the decay $\Xi_c^{0} \to
\Xi^{-} \pi^+$. We find $\alpha_{\Xi_c^{0}} \alpha_{\Xi} = 0.26 \pm
0.18{(stat)}^{+0.05}_{-0.04}{(syst)}$, using the world average value of
$\alpha_{\Xi} = -0.456 \pm 0.014$ we obtain $\alpha_{\Xi_c^{0}} = -0.56 \pm
0.39{(stat)}^{+0.10}_{-0.09}{(syst)}$. The physically allowed range of a decay
asymmetry parameter is $-1<\alpha<+1$. Our result prefers a negative value:
$\alpha_{\Xi_c^{0}}$ is $<0.1$ at the 90% CL. The central value occupies the
middle of the theoretically expected range but is not yet precise enough to
choose between models.

</DOC>
<DOC>
<DOCNO> 85241 </DOCNO>
An Introduction to Black Hole Evaporation


  Classical black holes are defined by the property that things can go in, but
don't come out. However, Stephen Hawking calculated that black holes actually
radiate quantum mechanical particles. The two important ingredients that result
in back hole evaporation are (1) the spacetime geometry, in particular the
black hole horizon, and (2) the fact that the notion of a "particle" is not an
invariant concept in quantum field theory. These notes contain a step-by-step
presentation of Hawking's calculation. We review portions of quantum field
theory in curved spacetime and basic results about static black hole
geometries, so that the discussion is self-contained. Calculations are
presented for quantum particle production for an accelerated observer in flat
spacetime, a black hole which forms from gravitational collapse, an eternal
Schwarzschild black hole, and charged black holes in asymptotically deSitter
spacetimes. The presentation highlights the similarities in all these
calculations. Hawking radiation from black holes also points to a profound
connection between black hole dynamics and classical thermodynamics. A theory
of quantum gravity must predicting and explain black hole thermodynamics. We
briefly discuss these issues and point out a connection between black hole
evaportaion and the positive mass theorems in general relativity.

</DOC>
<DOC>
<DOCNO> 84092 </DOCNO>
Birth of the Brane World


  Birth of the brane world is studied using the Hamiltonian approach. It is
shown that an inflating brane world can be created from nothing. The wave
function of the universe obtained from the Wheeler de-Witt equation and the
time-dependent Schr$\ddot{o}$dinger equation for quantized scalar fields on the
brane are the same as in the conventional 4-dimensional quantum cosmology if
the bulk is exactly the Anti-de Sitter spacetime. The effect of the massive
objects in the bulk is also discussed. This analysis tells us the presence of
the extra dimension imprints a nontrivial effect on the quantum cosmology of
the brane world. This fact is important for the analysis of the quantum
fluctuations in the inflationary scenario of the brane world.

</DOC>
<DOC>
<DOCNO> 67968 </DOCNO>
Do the precise measurements of the Casimir force agree with the


  An upper limit on the Casimir force is found using the dielectric functions
of perfect crystalline materials which depend only on well defined material
constants. The force measured with the atomic force microscope is larger than
this limit at small separations between bodies and the discrepancy is
significant. The simplest modification of the experiment is proposed allowing
to make its results more reliable and answer the question if the discrepancy
has any relation with the existence of a new force.

</DOC>
<DOC>
<DOCNO> 10826 </DOCNO>
Shot-noise suppression by Fermi and Coulomb correlations in ballistic


  We investigate the injection of degenerate Fermi-Dirac electrons into a
multimode ballistic conductor under the space-charge limited regime. The
nonequilibrium current fluctuations were found to be suppressed by both Coulomb
and Fermi correlations. We show that the Fermi shot-noise suppression factor is
limited below by the value 2kT/epsilon_F, where T is the temperature and
epsilon_F the Fermi energy of the injected electrons. The Coulomb noise
suppression factor may attain much lower values epsilon_F/2qU, because of its
dependence on the applied bias U >> kT/q. The asymptotic behaviour of the
overall shot-noise suppression factor in a high degenerate limit was found to
be kT/qU, independently of the material parameters.

</DOC>
<DOC>
<DOCNO> 101226 </DOCNO>
Local Mirror Symmetry and Type IIA Monodromy of Calabi-Yau manifolds


  We propose a monodromy invariant pairing $K_{hol}(X) \otimes H_3(X^\vee,\ZZ)
\to \IQ$ for a mirror pair of Calabi-Yau manifolds, $(X,X^\vee)$. This pairing
is utilized implicitly in the previous calculations of the prepotentials for
Gromov-Witten invariants. After identifying the pairing explicitly we interpret
some hypergeometric series from the viewpoint of homological mirror symmetry
due to Kontsevich. Also we consider the local mirror symmetry limit to del
Pezzo surfaces in Calabi-Yau 3-folds.

</DOC>
<DOC>
<DOCNO> 101087 </DOCNO>
Ground States in Non-relativistic Quantum Electrodynamics


  The excited states of a charged particle interacting with the quantized
electromagnetic field and an external potential all decay, but such a particle
should have a true ground state--one that minimizes the energy and satisfies
the Schr\"odinger equation. We prove quite generally that this state exists for
{\it all values} of the fine-structure constant and ultraviolet cutoff. We also
show the same thing for a many-particle system under physically natural
conditions.

</DOC>
<DOC>
<DOCNO> 120514 </DOCNO>
The evolution of AGB stars with convective overshoot


  The influence of extended convective mixing (overshoot) on asymptotic giant
branch stellar evolution is investigated in detail. The extended mixing is
treated time-dependently, and the efficiency declines exponentially with the
geometric distance from the convective boundary. It has been considered at all
convective boundaries, including the He-flash convection zone in the intershell
region which forms during the thermal pulses. Both the structural and the
chemical evolution are affected by the inclusion of overshoot. The main results
include a very efficient third dredge-up which leads to the formation of carbon
stars of low mass and luminosity. A C13 pocket which may serve as a neutron
source for the s-process can form after the third dredge-up has reached into
the C12 rich intershell. Overshoot applied to the pulse-driven convective zone
during the He-flash leads to a deeper penetration of the bottom of this
convective zone into the C/O core below the He-burning shell. This in turn
causes He4 to be less abundant in the intershell while C12 and O16 are more
abundant compared to calculations without overshoot. We show that overshoot at
the He-flash convection zone as well as at the base of the envelope convection
enhance the efficiency of the third dredge-up. Characteristic properties of the
structural and chemical evolution of AGB stars are presented.

</DOC>
<DOC>
<DOCNO> 11984 </DOCNO>
Transport Properties and Density of States of Quantum Wires with


  We review recent work on the random hopping problem in a
quasi-one-dimensional geometry of N coupled chains (quantum wire with
off-diagonal disorder). Both density of states and conductance show a
remarkable dependence on the parity of N. The theory is compared to numerical
simulations.

</DOC>
<DOC>
<DOCNO> 100641 </DOCNO>
Anti-holomorphic twistor and Symplectic structure


  It is well known that the twisters, section of twister space, classify the
almost complex structure on even dimensional Riemannian manifold $X$.
 In this paper, it will be proved that a harmonic and anti-holomorphic twister
is equivalent ti a symplectic structure on $X$.

</DOC>
<DOC>
<DOCNO> 101291 </DOCNO>
Representations of $U_{\epsilon}^{res}(sl_2)$ via Restricted q-Fock


  Two restricted $C[q,q^{-1}]-$forms of the well known q-boson algebra are
introduced and the corresponding restricted q-Fock spaces defined. All of the
irreducible highest weight representations, including the infinite dimensional
ones, of $U_\epsilon ^{res}(sl_2)$ of type 1 are constructed through the
restricted q-Fock spaces.

</DOC>
<DOC>
<DOCNO> 13584 </DOCNO>
The thermodynamics of portfolios


  We propose a new method of valuation of portfolios and their respective
investing strategies. To this end we define a canonical ensemble of portfolios
that allows to use the formalism thermodynamics.

</DOC>
<DOC>
<DOCNO> 12558 </DOCNO>
Andreev reflection in layered structures: implications for high T_c


  Andreev reflection is investigated in layered anisotropic normal metal /
superconductor (N/S) systems in the case of an energy gap \Delta in S not
negligible with respect to the Fermi energy E_F, as it probably occurs with
high critical temperature superconductors (HTS). We find that in these limits
retro-reflectivity, which is a fundamental feature of Andreev reflection, is
broken modifying sensitively transport across S/N interfaces. We discuss the
consequences for supercurrents in HTS Josephson junctions and for the midgap
states in S-N contacts

</DOC>
<DOC>
<DOCNO> 101345 </DOCNO>
A Sharp Bound for the Ratio of the First Two Dirichlet Eigenvalues of a


  For a domain $\Omega$ contained in a hemisphere of the $n$-dimensional
sphere $\SS^n$ we prove the optimal result $\lambda_2/\lambda_1(\Omega) \le
\lambda_2/\lambda_1(\Omega^{\star})$ for the ratio of its first two Dirichlet
eigenvalues where $\Omega^{\star}$, the symmetric rearrangement of $\Omega$ in
$\SS^n$, is a geodesic ball in $\SS^n$ having the same $n$-volume as $\Omega$.
We also show that $\lambda_2/\lambda_1$ for geodesic balls of geodesic radius
$\theta_1$ less than or equal to $\pi/2$ is an increasing function of
$\theta_1$ which runs between the value $(j_{n/2,1}/j_{n/2-1,1})^2$ for
$\theta_1=0$ (this is the Euclidean value) and $2(n+1)/n$ for $\theta_1=\pi/2$.
Here $j_{\nu,k}$ denotes the $k^{th}$ positive zero of the Bessel function
$J_{\nu}(t)$. This result generalizes the Payne-P\'{o}lya-Weinberger
conjecture, which applies to bounded domains in Euclidean space and which we
had proved earlier. Our method makes use of symmetric rearrangement of
functions and various technical properties of special functions. We also prove
that among all domains contained in a hemisphere of $\SS^n$ and having a fixed
value of $\lambda_1$ the one with the maximal value of $\lambda_2$ is the
geodesic ball of the appropriate radius. This is a stronger, but slightly less
accessible, isoperimetric result than that for $\lambda_2/\lambda_1$. Various
other results for $\lambda_1$ and $\lambda_2$ of geodesic balls in $\SS^n$ are
proved in the course of our work.

</DOC>
<DOC>
<DOCNO> 117699 </DOCNO>
Interferometric Astrometry of the Detached White Dwarf - M Dwarf Binary


  With HST FGS 3 we have determined a parallax for the white dwarf - M dwarf
interacting binary, Feige 24. The white dwarf (DA) component has an effective
temperature, T_eff of approximately 56,000 K degrees. A weighted average with
past parallax determinations (pi_abs = 14.6 +- 0.4 milliseconds of arc) narrows
the range of possible radius values, compared to past estimates. We obtain R_DA
= 0.0185 +- 0.0008 R_solar with uncertainty in the temperature and bolometric
correction the dominant contributors to the error. FGS photometry provides a
light curve entirely consistent with reflection effects. A recently refined
model Mass-Luminosity Relation (Baraffe et al. 1998) for low mass stars
provides a mass estimate for the M dwarf companion, M_dM = 0.37 +- 0.20
M_solar, where the mass range is due to metallicity and age uncertainties.
Radial velocities from Vennes and Thorstensen (1994) provide a mass ratio from
which we obtain M_DA = 0.49+0.19-0.05 ~ M_solar. Independently, our radius and
recent log_g determinations yield 0.44 < M_DA < 0.47 M_solar. In each case the
minimum DA mass is that derived by Vennes & Thorstensen from their radial
velocities and Keplerian circular orbits with inclination <= 90 degrees.
Locating Feige 24 on an M - R plane suggests a carbon core. Our radius and
these mass estimates yield a gamma_grav inconsistent with that derived by
Vennes & Thorstensen. We speculate on the nature of a third component whose
existence would resolve the discrepancy.

</DOC>
<DOC>
<DOCNO> 101635 </DOCNO>
Higher fundamental functors for simplicial sets


  This is a sequel to a previous paper, developing an intrinsic, combinatorial
homotopy theory for simplicial complexes; the latter form the cartesian closed
subcategory of 'simple presheaves' in !Smp, the topos of symmetric simplicial
sets, or presheaves on the category of finite, positive cardinals.
   We show here how this homotopy theory can be extended to the topos itself,
!Smp. As a crucial advantage, the fundamental groupoid functor !Smp --> Gpd is
left adjoint to a natural functor Gpd --> !Smp, the symmetric nerve of a
groupoid, and preserves all colimits - a strong van Kampen property. Similar
results hold in all higher dimensions. Analogously, a notion of
(non-reversible) directed homotopy can be developed in the ordinary simplicial
topos Smp, with applications to image analysis as in the previous paper. We
have now a 'homotopy n-category functor' Smp --> n-Cat, left adjoint to a nerve
functor.
   This construction can be applied to various presheaf categories; the basic
requirements seem to be: finite products of representables are finitely
presentable and there is a representable 'standard interval'.

</DOC>
<DOC>
<DOCNO> 117300 </DOCNO>
The Arrow of Time


  It is shown that (special) relativistically dilated time is the vector sum of
rest time and time induced by movement in three dimensional space exeeding the
rest time component and that the first vector is orthogonally directed relative
to our three dimensional space. This again implies that its origin lies in the
movement of three dimensional space relative to a four dimensional manifold.
The theory predicts asymmetrical time dilation.

</DOC>
<DOC>
<DOCNO> 102297 </DOCNO>
Index Growth of hypersurfaces with constant mean curvature


  In this paper we give the precise index growth for the embedded hypersurfaces
of revolution with constant mean curvature (cmc) 1 in $\R^{n}$ (Delaunay
unduloids). When $n=3$, using the asymptotics result of Korevaar, Kusner and
Solomon, we derive an explicit asymptotic index growth rate for finite topology
cmc 1 surfaces with properly embedded ends. Similar results are obtained for
hypersurfaces with cmc bigger than 1 in hyperbolic space.

</DOC>
<DOC>
<DOCNO> 85455 </DOCNO>
On fine differentiability properties of horizons and applications to


  We study fine differentiability properties of horizons. We show that the set
of end points of generators of a n-dimensional horizon H (which is included in
a (n+1)-dimensional space-time M) has vanishing n-dimensional Hausdorff
measure. This is proved by showing that the set of end points of generators at
which the horizon is differentiable has the same property. For 1\le k\le n+1 we
show (using deep results of Alberti) that the set of points where the convex
hull of the set of generators leaving the horizon has dimension k is ``almost a
C^2 manifold of dimension n+1-k'': it can be covered, up to a set of vanishing
(n+1-k)-dimensional Hausdorff measure, by a countable number of C^2 manifolds.
We use our Lorentzian geometry results to derive information about the fine
differentiability properties of the distance function and the structure of cut
loci in Riemannian geometry.

</DOC>
<DOC>
<DOCNO> 122845 </DOCNO>
Steady-state structure of relativistic collisionless shocks


  We explore analytically the structure of relativistic shock and solitary wave
solutions in collisionless plasmas. In the wave frame of reference, a cold
plasma is flowing from one end and impacting on a low velocity plasma. First we
show that under astrophysical conditions, a cold electron-positron plasma is
unstable with respect to a two-stream instability in the interface between
these regions. The instability heats the inflowing cold plasma rapidly, on a
timescale comparable to the inverse of its plasma frequency. We then derive
time-independent equations to describe the resulting hot state of the pair
plasma, and describe the conditions under which the spatially uniform solution
is the unique stable solution for the post shock conditions. We also examine
plasmas composed of cold protons and hot electrons, and show that the spatially
uniform solution is the unique stable solution there as well. We state the
shock jump conditions which connect a cold, electron-proton plasma to a hot
electron-proton plasma. The generic feature evident in all of these models is
that the plasma's initial, directed kinetic energy gets almost completely
converted into heat. The magnetic field plays the role of catalyst which can
induce the plasma instability, but our solutions indicate that the macroscopic
field only gets amplified by a factor of approximately three in the frame of
the shock.

</DOC>
<DOC>
<DOCNO> 178487 </DOCNO>
Spin-Orbit Splitting in Non-Relativistic and Relativistic


  The splitting of single-particle energies between spin-orbit partners in
nuclei is examined in the framework of different self-consistent approachs,
non-relativistic as well as relativistic. Analytical expressions of spin-orbit
potentials are given for various cases. Proton spin-orbit splittings are
calculated along some isotopic chains (O, Ca, Sn) and they are compared with
existing data. It is found that the isotopic dependence of the relativistic
mean field predictions is similar to that of some Skyrme forces while the
relativistic Hartree-Fock approach leads to a very different dependence due to
the strong non-locality.

</DOC>
<DOC>
<DOCNO> 152520 </DOCNO>
On the path integral representation for Wilson loops and the non-Abelian


  This paper is a revised version of our recent publication Faber et al., Phys.
Rev. D62 (2000) 025019, hep-th/9907048. The main revision concerns the
expansion into group characters that we have used for the evaluation of path
integrals over gauge degrees of freedom. In the present paper we apply the
expansion recommended by Diakonov and Petrov in hep-lat/0008004. Our former
expansion was approximate and in the region of the particular values of
parameters violated the completeness condition by 1.4%. We show that by using
the expansion into characters recommended by Diakonov and Petrov in
hep-lat/0008004 our previous results are retained and the path integral over
gauge degrees of freedom for Wilson loops derived by Diakonov and Petrov (Phys.
Lett. B224 (1989) 131 and hep-lat/0008004) by using a special regularization is
erroneous and predicts zero value for the Wilson loop. We give comments on the
paper hep-lat/0008004.

</DOC>
<DOC>
<DOCNO> 12788 </DOCNO>
Feedback effects and the self-consistent Thouless criterion of the


  We propose a fully microscopic theory of the anomalous normal state of the
attractive Hubbard model in the low-density limit that accounts for propagator
renormalization. Our analytical conclusions, which focus on the thermodynamic
instabilities contained in the self-consistent equations associated with our
formulation, have been verified by our comprehensive numerical study of the
same equations. The resulting theory is found to contain no transitions at
non-zero temperatures for all finite lattices, and we have confirmed, using our
numerical studies, that this behaviour persists in the thermodynamic limit for
low-dimensional systems.

</DOC>
<DOC>
<DOCNO> 101481 </DOCNO>
From moment graphs to intersection cohomology


  We describe a method of computing equivariant and ordinary intersection
cohomology of certain varieties with actions of algebraic tori, in terms of
structure of the zero- and one-dimensional orbits. The class of varieties to
which our formula applies includes Schubert varieties in flag varieties and
affine flag varieties. We also prove a monotonicity result on local
intersection cohomology stalks.

</DOC>
<DOC>
<DOCNO> 9414 </DOCNO>
Quasi-Particle Spectrum around a Single Vortex in Superconductors -


  Making use of the Bogoliubov-de Gennes equation, we study the quasi-particle
spectrum and the vortex core structure of a single vortex in quasi 2D s-wave
superconductors for small p_F xi_0, where p_F is the Fermi momentum and
xi_0=v_F/Delta_0 is the coherence length (hbar=1). During our numerical
calculation the particle number is conserved for each p_F xi_0. In particular,
we find that there are only 1 or 2 bound states for p_F xi_0=1. Also, for p_F
xi_0=1, the Kramer-Pesch effect ceases to exist at around T/T_c= 0.3.

</DOC>
<DOC>
<DOCNO> 84388 </DOCNO>
Cosmological Time in (2+1) - Gravity


  We consider maximal globally hyperbolic flat (2+1) spacetimes with compact
space S of genus g>1. For any spacetime M of this type, the length of time that
the events have been in existence is M defines a global time, called the
cosmological time CT of M, which reveals deep intrinsic properties of
spacetime. In particular, the past/future asymptotic states of the cosmological
time recover and decouple the linear and the translational parts of the
ISO(2,1)-valued holonomy of the flat spacetime. The initial singularity can be
interpreted as an isometric action of the fundamental group of S on a suitable
real tree. The initial singularity faithfully manifests itself as a lack of
smoothness of the embedding of the CT level surfaces into the spacetime M. The
cosmological time determines a real analytic curve in the Teichmuller space of
Riemann surfaces of genus g, which connects an interior point (associated to
the linear part of the holonomy) with a point on Thurston's natural boundary
(associated to the initial singularity).

</DOC>
<DOC>
<DOCNO> 100685 </DOCNO>
Nonarithmetic superrigid groups: Counterexamples to Platonov's


  Margulis showed that "most" arithmetic groups are superrigid. Platonov
conjectured, conversely, that finitely generated linear groups which are
superrigid must be of "arithmetic type." We construct counterexamples to
Platonov's Conjecture.

</DOC>
<DOC>
<DOCNO> 70237 </DOCNO>
General brane cosmologies and their global spacetime structure


  Starting from a completely general standpoint, we find the most general
brane-Universe solutions for a three-brane in a five dimensional spacetime. The
brane can border regions of spacetime with or without a cosmological constant.
Making no assumptions other than the usual cosmological symmetries of the
metric, we prove that the equations of motion form an integrable system, and
find the exact solution. The cosmology is indeed a boundary of a (class II)
Schwarzschild-AdS spacetime, or a Minkowski (class I) spacetime. We analyse the
various cosmological trajectories focusing particularly on those bordering
vacuum spacetimes. We find, not surprisingly, that not all cosmologies are
compatible with an asymptotically flat spacetime branch. We comment on the role
of the radion in this picture.

</DOC>
<DOC>
<DOCNO> 10347 </DOCNO>
Dynamics of Lennard-Jones clusters: A characterization of the


  The potential energy surface (PES) of Lennard-Jones clusters is investigated
using the activation-relaxation technique (ART). This method defines events in
the configurational energy landscape as a two-step process: (a) a configuration
is first activated from a local minimum to a nearby saddle-point and (b) is
then relaxed to a new minimum. Although ART has been applied with success to a
wide range of materials such as a-Si, a-SiO2 and binary Lennard-Jones glasses,
questions remain regarding the biases of the technique. We address some of
these questions in a detailed study of ART-generated events in Lennard-Jones
(LJ) clusters, a system for which much is already known. In particular, we
study the distribution of saddle-points, the pathways between configurations,
and the reversibility of paths. We find that ART can identify all trajectories
with a first-order saddle point leaving a given minimum, is fully reversible,
and samples events following the Boltzmann weight at the saddle point.

</DOC>
<DOC>
<DOCNO> 70325 </DOCNO>
Applications of QCD Factorization in Hadronic B Decays


  We review recent advances in the theory of strong-interaction effects and
final-state interactions in hadronic weak decays of heavy mesons. In the
heavy-quark limit, the amplitudes for most nonleptonic, two-body B decays can
be calculated from first principles and expressed in terms of semileptonic form
factors and light-cone distribution amplitudes. We summarize the main features
of this novel QCD factorization and discuss its phenomenological applications
to B -> D^(*) L decays (with L a light meson), and to the rare charmless decays
B -> pi K and B -> pi pi.

</DOC>
<DOC>
<DOCNO> 80723 </DOCNO>
Three-Quark Potential in SU(3) Lattice QCD


  The static three-quark (3Q) potential is measured in the SU(3) lattice QCD
with $12^3 \times 24$ and $\beta=5.7$ at the quenched level. From the 3Q Wilson
loop, the 3Q ground-state potential $V_{\rm 3Q}$ is extracted using the
smearing technique for the ground-state enhancement. With accuracy better than
a few %, $V_{\rm 3Q}$ is well described by a sum of a constant, the two-body
Coulomb term and the three-body linear confinement term $\sigma_{\rm 3Q} L_{\rm
min}$, where $L_{\rm min}$ denotes the minimal length of the color flux tube
linking the three quarks. By comparing with the Q-$\bar {\rm Q}$ potential, we
find a universal feature of the string tension, $\sigma_{\rm 3Q} \simeq
\sigma_{\rm Q \bar Q}$, as well as the one-gluon-exchange result for the
Coulomb coefficient, $A_{\rm 3Q} \simeq \frac12 A_{\rm Q \bar Q}$.

</DOC>
<DOC>
<DOCNO> 117805 </DOCNO>
The Host Galaxy of the Lensed Quasar Q 0957+561


  Infrared images of the Q 0957+561 gravitational lens obtained with the Hubble
Space Telescope show two large (\sim 5 arcsec) lensed images of the z_s=1.41
quasar host galaxy. Parts of the host galaxy are doubly-imaged like the quasar,
while other parts are quadruply-imaged. The distortions of the host galaxy
offer the best probe yet of the global structure of the lensing potential,
which is essential for determining the Hubble constant from the measured time
delay. The distortions are inconsistent with the predictions of previously
published lens models, which invalidates those models and their implications
for H_0. New models show that the distortions finally break the long-standing
degeneracy between the shape of the lens galaxy and the tidal shear contributed
by the cluster containing the lens galaxy. The shape of the lens galaxy's mass
distribution must be remarkably similar to the shape of its luminosity
distribution, and most models that produce reasonable values for the Hubble
constant roughly match the observed ellipticity gradient and isophote twist of
the lens galaxy. Also, the cluster must be non-spherical and produce a
relatively small tidal shear. Although there are still degeneracies in the lens
models that lead to a 25% uncertainty in the derived value of the Hubble
constant, there are also strong prospects for new observations to further
improve the constraints and reduce the uncertainties.

</DOC>
<DOC>
<DOCNO> 101531 </DOCNO>
Nonlinear Beam Dynamics and Effects of Wigglers


  We present the applications of variational--wavelet approach for the
analytical/numerical treatment of the effects of insertion devices on beam
dynamics. We investigate the dynamical models which have polynomial
nonlinearities and variable coefficients. We construct the corresponding
wavelet representation for wigglers and undulator magnets.

</DOC>
<DOC>
<DOCNO> 117603 </DOCNO>
Combined color indexes and photometric structure of galaxies NGC 834 and


  We present the results of BVRI photometry of two galaxies with active star
formation: NGC 834 and NGC 1134. Combined color index Q_{BVI} was used to
investigate the photometrical structure of the galaxies. Index Q_{BVI} is not
affected by internal extinction and is sensitive to the presence of blue stars.
  Ring-like region with active star formation at 15" from the center reveals
itself in the Q_{BVI} map of NGC 834. Three-arm spiral structure is well-seen
on the Q_{BVI} map of NGC 1134.
  We propose to use the combined indexes Q_{BVI} and similarly defined indices
as a tracers of Star Formation activity and structure of dusty galaxies.

</DOC>
<DOC>
<DOCNO> 117489 </DOCNO>
Clues to the origin of parsec to kilo-parsec jet misalignments in EGRET


  The apparent position angle difference $\Delta$PA between parsec and
kilo-parsec jets in blazars can be related to the bending properties of the
jets. We present correlations between the misalignment $\Delta$PA and the ratio
of radio to broad-line emission for a sample of $\gamma$-ray blazars. The
present study is limited to EGRET sources due to uniform data for the radio and
optical properties of these sources being easily available. The broad-line
emission is known to be a good indicator of the accretion power for both steep
and flat-spectrum quasars. We find significant correlations between $\Delta$PA
and the ratio of radio flux (total and radio core flux respectively) to
broad-line flux, which is consistent with the beaming scenario. A weak
correlation between $\Delta$PA and the ratio of extended radio to broad-line
flux might imply that the intrinsic bend of the jet is related with the ratio
of jet mechanical power to accretion power.

</DOC>
<DOC>
<DOCNO> 178936 </DOCNO>
Low energy scattering and photoproduction of $\eta$-mesons on deuterons


  Photo-production of $\eta$-mesons and their collisions with light nuclei are
studied within the Alt-Grassberger-Sandhas (AGS) formalism for different
parameters of $\eta N$ interaction. A three-body resonance or a quasi-bound
state is found close to the $\eta d$ threshold. Expected manifestation of this
resonant behavior of $\eta d$ elastic scattering in various processes involving
$\eta d$-system in their final states was found in calculations of the $\gamma
d \to \eta d$ reaction in the framework of modified AGS equations. These
calculations revealed peaks in the energy dependence of the total cross-section
almost at the same energies as in the elastic $\eta d$ scattering. Meanwhile,
such peaks did not appear in the impulse approximation (i.e. when $\eta d$
resonance was not taken into account). This sheds some light on the nature of
the enhancement of $\eta$ photo-production on deuteron observed recently in the
low energy experiments.

</DOC>
<DOC>
<DOCNO> 122234 </DOCNO>
Observations of a Series of Six Recent Glitches in the Crab Pulsar


  From 1995 to 1999, daily monitoring of the radio emission from the Crab
pulsar at the Green Bank and Jodrell Bank observatories revealed a series of
six sudden rotational spinups or glitches, doubling the number of glitches
observed for this pulsar since 1969. With these observations, the range of time
intervals between significant Crab glitches has widened considerably,
indicating that the occurrence of Crab glitches may be more random than
previously thought. The new glitch amplitudes ($\Delta\nu/\nu$) span an order
of magnitude from 2e-9 to 3e-8. Except in one case, which we suggest may
represent an ``aftershock'' event, the frequency jumps display an exponential
recovery with a timescale of $\sim$3 days for the smaller glitches and $\sim$10
days for the largest (1996) glitch. In the largest event, a portion of the
spinup was resolved in time, as was previously reported for the 1989 glitch. A
pronounced change in frequency derivative also occurs after each glitch and is
correlated with the size of the initial frequency jump, although for some of
the smaller glitches this appears to be a temporary effect. We discuss the
properties of the ensemble of observed Crab glitches and compare them with the
properties of Vela glitches, highlighting those differences which must be
explained by evolutionary models.

</DOC>
<DOC>
<DOCNO> 102326 </DOCNO>
Lattice polytopes with distinct pair-sums


  Let P be a lattice polytope in R^n, and let P \cap Z^n = {v_1,...,v_N}. If
the N + \binom N2 points 2v_1,...,2v_N; v_1+v_2,...v_{N-1}+v_N are distinct, we
say that P is a "distinct pair-sum" or "dps" polytope. We show that, if P is a
dsp polytope in R^n, then N \le 2^n, and, for every n, we construct dps
polytopes in R^n which contain 2^n lattice points. We also discuss the relation
between dps polytopes and the study of sums of squares of real polynomials.

</DOC>
<DOC>
<DOCNO> 122687 </DOCNO>
Gamma Ray Burst progenitors - a case for helium star mergers


  Recently much work in Gamma-Ray Burst (GRB) studies was devoted to revealing
the nature of outburst mechanism and to looking for GRB progenitors. Several
types of progenitors were proposed for GRBs. Most promising objects are
collapsars, compact object binaries, Helium star mergers and recently discussed
supernovae. In this paper we consider four proposed binary star progenitors of
GRBs: double neutron star (NS-NS), black hole neutron star (BH-NS), black hole
white dwarf (BH-WD) mergers and Helium star mergers (He-BH). Helium star
mergers are a possible outcome of common envelope evolution of a compact object
entering the envelope of a giant with a helium core.
  Using population synthesis we calculate number of the binary progenitors and
show that BH-WD and Helium star mergers dominate population of the proposed
binary progenitors. Comparison of distribution of different binary mergers
around galaxies they are born in, with localization of GRB afterglows in their
host galaxies shows that only Helium mergers may be responsible for GRBs with
observed afterglows while it excludes NS-NS, BH-NS and BH-WD systems as GRB
progenitors. Assuming that all GRBs come from Helium star mergers and comparing
numbers of Helium star mergers with observed BATSE GRB rate let us derive upper
limit on GRB collimation to be 4 degrees.

</DOC>
<DOC>
<DOCNO> 68625 </DOCNO>
Flavor Violation as a Probe of the MSSM Higgs Sector


  At moderate to large tan(beta), it is no longer possible to simultaneously
diagonalize the masses of quarks and their couplings to the neutral Higgs
bosons. The resulting flavor violations of the form (\bar b_R d_L H) and (\bar
b_R s_L H) do not generate large meson-anti-meson mixing amplitudes but do
generate large contributes to rare decays such as B_s -> mu mu. Run II of the
Tevatron willl probe a large region of interesting MSSM parameter space through
this decay channel. This talk is based on results obtained with K.S. Babu and
presented in hep-ph/9909476.

</DOC>
<DOC>
<DOCNO> 72273 </DOCNO>
Can Subquark Model explain CP violation ?


  We study CP violation phenomena with the subquark model which is previously
proposed by us. Our subquark model claims that ``direct'' and ``indirect'' CP
violation originate from different sources, which are both belonging to
subquark dynamics. We discuss KTeV experiment and CP-asymmetry of
$(B_{d}\to{J/{\psi}K_{s}})$-and $(B_{d}\to{\pi}{\pi})$-decay.
 This model predicts : the phases of indirect CP violation :
 ${\theta}_K={\theta}_D={\theta}_{B_s}={\theta}_{T_c}\simeq(1/2){\theta}_{B_d}
 \simeq (1/2){\theta}_{T_u}$.

</DOC>
<DOC>
<DOCNO> 119864 </DOCNO>
Azimuthally symmetric MHD and two-fluid equilibria with arbitrary flows


  Magnetohydrodynamic (MHD) and two-fluid quasi-neutral equilibria with
azimuthal symmetry, gravity and arbitrary ratios of (nonrelativistic) flow
speed to acoustic and Alfven speeds are investigated. In the two-fluid case,
the mass ratio of the two species is arbitrary, and the analysis is therefore
applicable to electron-positron plasmas. The methods of derivation can be
extended in an obvious manner to several charged species. Generalized
Grad-Shafranov equations, describing the equilibrium magnetic field, are
derived. Flux function equations and Bernoulli relations for each species,
together with Poisson's equation for the gravitational potential, complete the
set of equations required to determine the equilibrium. These are
straightforward to solve numerically. The two-fluid system, unlike the MHD
system, is shown to be free of singularities. It is demonstrated analytically
that there exists a class of incompressible MHD equilibria with magnetic
field-aligned flow. A special sub--class first identified by S. Chandrasekhar,
in which the flow speed is everywhere equal to the local Alfven speed, is
compatible with virtually any azimuthally symmetric magnetic configuration.
Potential applications of this analysis include extragalactic and stellar jets,
and accretion disks.

</DOC>
<DOC>
<DOCNO> 117973 </DOCNO>
The structure and evolution of weakly self-interacting cold dark matter


  The evolution of halos consisting of weakly self-interacting dark matter
particles is investigated using a new numerical Monte-Carlo N-body method. The
halos initially contain kinematically cold, dense 1/r-power-law cores. For
interaction cross sections (sigma/mp) >= 10-100 cm**2/g weak self-interaction
leads to the formation of isothermal, constant density cores within a Hubble
time as a result of heat transfer into the cold inner regions. This core
structure is in good agreement with the observations of dark matter rotation
curves in dwarf galaxies. The isothermal core radii and core densities are a
function of the halo scale radii and scale masses which depend on the
cosmological model. Adopting the currently popular LCDM model, the predicted
core radii and core densities are on good agreement with the observations. For
large interaction cross sections, massive dark halos with scale radii rs >=
14000 cm**2/g/(sigma/mp) kpc could experience core collapse during their
lifetime, leading to cores with singular isothermal density profiles.

</DOC>
<DOC>
<DOCNO> 11629 </DOCNO>
Thermal properties of ferrimagnetic systems


  The heat capacity of some ferrimagnets has additional structures like a
shoulder in the Schottky-like peak, or emergence of a second peak when an
external magnetic field is applied. It is shown here that as long as spin
wave-spin wave interactions are ignored in a ferrimagnet, the ferromagnetic and
antiferromagnetic elementary excitation spectra give rise to two independent
heat capacity peaks, one enveloped by the other, which add up to give the peak
for the total system. Taking this into account helps understand the additional
structures in the peaks. Moreover, the classification of ferrimagnets into
predominantly antiferromagnetic, ferromagnetic, or a mixture of the two is
shown to be validated by studying them under additional influences like
dimerization and frustration. Because these two are shown to influence the
ferromagnetic and antiferromagnetic dispersion relations - and hence the
quantities like heat capacity and magnetic susceptibility - by different
amounts, the characterisation of ferrimagnetic systems ($1,1/2$), ($3/2,1$) and
($3/2,1/2$) is brought out more clearly. Both these influences enhance
antiferromagnetic character.

</DOC>
<DOC>
<DOCNO> 122897 </DOCNO>
EUV and soft X-rays from clusters of galaxies - the `cluster


  Clusters of galaxies are strong emitters of EUV and soft X-rays substantially
in excess of the contribution from the hot intra-cluster medium at X-ray
temperatures. After the initial discovery of EUV excess emission in the Virgo
cluster, the phenomenon was reported also for the Coma, A1795 and A2199
clusters. Recent reobservations confirmed the finding, and further searches on
a large sample of nearby galaxy clusters are clearly revealing the cosmological
impact of the discovery.

</DOC>
<DOC>
<DOCNO> 71130 </DOCNO>
Remarks on models with singlet neutrino in large extra dimensions


  Small Dirac masses for neutrinos are natural in models with singlet fermions
in large extra dimensions with quantum gravity scale M_{\ast} \sim 1- 100 TeV.
We study two modifications of the minimal model in order to obtain the mass
scale relevant for atmospheric neutrino oscillations with at most O(1)
higher-dimensional Yukawa couplings and with M_{\ast} \sim a few TeV. 1) In
models with singlet fermions in smaller number of extra dimensions than
gravity, we find that the effects on BR (\mu \to e \gamma) and on
charged-current universality in \pi^- \to e \bar{\nu}, \mu \bar{\nu} decays are
suppressed as compared to that in the minimal model with neutrino and gravity
in the same space. 2) If small Dirac masses for the singlets are added along
with lepton number violating couplings, then the mass scales and mixing angles
for neutrino oscillations can be different from those relevant for \mu \to e
\gamma and \pi^- \to e \bar{\nu}, \mu \bar{\nu}. Thus, in both modified models
the constraints on M_{\ast} from BR (\mu \to e \gamma) and \pi^- \to e
\bar{\nu}, \mu \bar{\nu} decays can be significantly relaxed. Furthermore,
constraints from supernova 1987a strongly disfavor oscillations of active
neutrinos to sterile neutrinos in both the minimal and the modified models.

</DOC>
<DOC>
<DOCNO> 69906 </DOCNO>
The Nobel Prize in Physics 1999


  The last Nobel Prize of the Millenium in Physics has been awarded jointly to
Professor Gerardus 't Hooft of the University of Utrecht in Holland and his
thesis advisor Professor Emeritus Martinus J.G. Veltman of Holland. According
to the Academy's citation, the Nobel Prize has been awarded for 'elucidating
the quantum structure of electroweak interaction in Physics'. It further goes
on to say that they have placed particle physics theory on a firmer
mathematical foundation. In this short note, we will try to understand both
these aspects of the award. The work for which they have been awarded the Nobel
Prize was done in 1971. However, the precise predictions of properties of
particles that were made possible as a result of their work, were tested to a
very high degree of accuracy only in this last decade. This was done in a
series of measurements in the experiments in the accelerator laboratories at
CERN (Geneva) and Fermilab. To understand the full significance of this Nobel
Prize, we will have to summarise briefly the developement of our current
theoretical framework about the basic constituents of matter and the forces
which hold them together. In fact the path can be partially traced in a chain
of Nobel prizes starting from one in 1965 to S. Tomonaga, J. Schwinger and R.
Feynman, to the one to S.L. Glashow, A. Salam and S. Weinberg in 1979, and then
to C. Rubia and Simon van der Meer in 1984 ending with the current one.

</DOC>
<DOC>
<DOCNO> 85432 </DOCNO>
Diffeomorphism on Horizon as an Asymptotic Isometry of Schwarzschild


  It is argued that the diffeomorphism on the horizontal sphere can be regarded
as a nontrivial asymptotic isometry of the Schwarzschild black hole. We propose
a new boundary condition of asymptotic metrics near the horizon and show that
the condition admits the local time-shift and diffeomorphism on the horizon as
the asymptotic symmetry.

</DOC>
<DOC>
<DOCNO> 119958 </DOCNO>
The Observation of Lunar Impacts


  The intense activity of cratering on the Moon and in the inner regions of the
solar system was accomplished during the first 10^9 years [1]. Occasionally,
some impact events occur even nowadays. In Section 1, we treat, from a
historical point of view, the Earth-based observation of lunar impacts. In
Section 2, we consider the visibility conditions of such events evaluating the
luminosity of the background upon which an impact shines. In Section~3, the
luminosity of an impact is discussed. The occurrence of lunar impact events
outside of meteor shower periods is calculated using the hourly rate of the
sporadic meteors and their population index. The evidence of a larger rate of
impacts of meteoroids in the past under these hypotheses is presentend in the
last section.

</DOC>
<DOC>
<DOCNO> 83249 </DOCNO>
Finite-State Non-Concatenative Morphotactics


  Finite-state morphology in the general tradition of the Two-Level and Xerox
implementations has proved very successful in the production of robust
morphological analyzer-generators, including many large-scale commercial
systems. However, it has long been recognized that these implementations have
serious limitations in handling non-concatenative phenomena. We describe a new
technique for constructing finite-state transducers that involves reapplying
the regular-expression compiler to its own output. Implemented in an algorithm
called compile-replace, this technique has proved useful for handling
non-concatenative phenomena; and we demonstrate it on Malay full-stem
reduplication and Arabic stem interdigitation.

</DOC>
<DOC>
<DOCNO> 11182 </DOCNO>
Effect of magnetic fluctuations on the normal state properties of


  We investigate the normal state transport properties of Sr$_2$RuO$_4 $ and we
show that a consistent explanation of the experimental results can be obtained
assuming that the system is near a quantum phase transition. Within the
framework of a self-consistent spin fluctuation theory, we calculate the
temperature variation of some relevant physical quantities and we discuss a
possible microscopic origin of the quantum phase transition.

</DOC>
<DOC>
<DOCNO> 13369 </DOCNO>
Semiclassical Solution of the Quantum Hydrodynamic Equation for Trapped


  In this paper the quantum hydrodynamic equation describing the collective,
low energy excitations of a dilute atomic Bose gas in a given trapping
potential is investigated with the JWKB semiclassical method. In the case of
spherically symmetric harmonic confining potential a good agreement is shown
between the semiclassical and the exact energy eigenvalues as well as wave
functions. It is also demonstrated that for larger quantum numbers the
calculation of the semiclassical wave function is numerically more stable than
the exact polynomial with large alternating coefficients.

</DOC>
<DOC>
<DOCNO> 152496 </DOCNO>
D-branes in group manifolds and flux stabilization


  We consider D-branes in group manifolds, from the point of view of open
strings and using the Born-Infeld action on the brane worldvolume. D-branes
correspond to certain integral (twined) conjugacy classes. We explain the
integrality condition on the conjugacy classes in both approaches. In the
Born-Infeld description, the D-brane worldvolume is stabilized against
shrinking by a subtle interplay of quantized U(1) fluxes and the non-triviality
of the B-field.

</DOC>
<DOC>
<DOCNO> 70977 </DOCNO>
Spectroscopy "windows" of quark-antiquark mesons and glueballs with


  Regge trajectories of quark-antiquark mesons can be well approximated for
phenomenology purposes by a specific nonlinear form, reflecting that the flux
tubes cannot be arbitrarily large, but break due to the effect of
pair-production. If confirmed, this would imply that there is only a finite
number of bound states on each trajectory, and consequently, an existence of
``spectroscopy windows'' for each flavor. Here we present our results for these
windows.

</DOC>
<DOC>
<DOCNO> 13212 </DOCNO>
Quantum carpet interferometry for trapped atomic Bose-Einstein


  We propose an ``interferometric'' scheme for Bose-Einstein condensates using
near-field diffraction. The scheme is based on the phenomenon of intermode
traces or quantum carpets; we show how it may be used in the detection of weak
forces.

</DOC>
<DOC>
<DOCNO> 170321 </DOCNO>
Quantum Distribution of Gaussian Keys with Squeezed States


  A continuous key distribution scheme is proposed that relies on a pair of
canonically conjugate quantum variables. It allows two remote parties to share
a secret Gaussian key by encoding it into one of the two quadrature components
of a single-mode electromagnetic field. The resulting quantum cryptographic
information vs disturbance tradeoff is investigated for an individual attack
based on the optimal continuous cloning machine. It is shown that the
information gained by the eavesdropper then simply equals the information lost
by the receiver.

</DOC>
<DOC>
<DOCNO> 69060 </DOCNO>
Are neutral Goldstone bosons initiating very energetic air showers and


  We consider two recently accentuated, unusual empirical results concerning
cosmic-ray events at high energies. We show that the possibility for a
correlated explanation is provided by new dynamics which arises from collisions
of a neutral Goldstone boson as a component of the highest-energy cosmic rays.

</DOC>
<DOC>
<DOCNO> 170693 </DOCNO>
Teleportation of entangled states and dense coding using a multiparticle


  A set of protocols for teleportation and dense coding tasks with the use of a
N particle quantum channel, presented by entangled states of the GHZ class, is
introduced, when N>2. Using a found representation for the multiparticle
entangled states of the GHZ class, it has shown, that for dense coding schemes
enhancement of the classical capacity of the channel due from entanglement is
N/N-1. If N>2 there is no one - to -one correspondence between teleportation
and dense coding schemes in comparison with the EPR channel is exploited. A set
of schemes, for which two additional operations as entanglement and
disentanglement are permitted, is considered.

</DOC>
<DOC>
<DOCNO> 99280 </DOCNO>
Knuth-Bendix for groups with infinitely many rules


  It is shown how to use a small finite state automaton in two variables in
order to carry out the Knuth-Bendix process for rewriting words in a group in
shortlex order. The two-variable automaton can be used to store an infinite set
of rules and to carry out fast reduction of arbitrary words using this infinite
set. We introduce a new operation, which we call welding, which applies to an
arbitrary finite state automaton. We show how to improve on the standard subset
construction to determinize a non-deterministic automaton under special
conditions which hold in our situation.

</DOC>
<DOC>
<DOCNO> 40064 </DOCNO>
Technicolor 2000


  This review is based on lectures on technicolor and extended technicolor
presented at the Frascati Spring School in May 2000. I summarize the motivation
and structure of this theory of dynamical breaking of electroweak and flavor
symmetries. Particular attention is paid to the main phenomenological obstacles
to this picture-flavor-changing neutral currents, precision electroweak
measurements, and the large top-quark mass-and their proposed
resolutions-walking technicolor and topcolor-assisted technicolor. I then
discuss the signatures for technicolor and the existing and upcoming searches
for them at LEP, the Tevatron Collider, and the Large Hadron Collider. The
final section lists some outstanding theoretical questions.

</DOC>
<DOC>
<DOCNO> 40625 </DOCNO>
A Measurement of the Branching Ratio and Asymmetry of the Decay


  We have studied the rare weak radiative hyperon decay Cascade0-->Sigma0/gamma
in the KTeV experiment at Fermilab. We have identified 4045 signal events over
a background of 804 events. The dominant Cascade0-->Lambda/pi0 decay, which was
used for normalization, is the only important background source. An analysis of
the acceptance of both modes yields a branching ratio of
BR(Cascade0-->Sigma0/gamma)=(3.34 +/- 0.05 +/- 0.09) x 10^(-3). By analyzing
the final state decay distributions, we have also determined that the Sigma0
emission asymmetry parameter for this decay is alpha = -0.63 +/- 0.09.

</DOC>
<DOC>
<DOCNO> 102469 </DOCNO>
Martin's Axiom is Consistent with the Existence of Nowhere Trivial


  Martin's Axiom does not imply that all automorphisms of P(N)/[N]^{<aleph_0}
are somewhere trivial.

</DOC>
<DOC>
<DOCNO> 69572 </DOCNO>
Gauge and Topological Symmetries in the Bulk Quantization of Gauge


  A gauge theory with 4 physical dimensions can be consistently expressed as a
renormalizable topological quantum field theory in 5 dimensions. We extend the
symmetries in the 5-dimensional framework to include not only a topological
BRST operator S that encodes the invisibility of the "bulk" (the fifth
dimension), but also a gauge BRST operator W that encodes gauge-invariance and
selects observables. These symmetries provide a rich structure of Ward
identities which assure the renormalizability of the theory, including
non-renormalization theorems. The 5-dimensional approach considerably
simplifies conceptual questions such as for instance the Gribov phenomenon and
fermion doubling. A confinement scenario in the 5-dimensional framework is
sketched. We detail the five-dimensional mechanism of anomalies, and we exhibit
a natural lattice discretization that is free of fermion doubling.

</DOC>
<DOC>
<DOCNO> 174528 </DOCNO>
MEVSIM: A Monte Carlo Event Generator for STAR


  A fast, simple to use Monte Carlo based event generator is presented which is
intended to facilitate simulation studies and the development of analysis
software for the Solenoidal Tracker at RHIC (Relativistic Heavy Ion Collider)
(STAR) experiment at the Brookhaven National Laboratory (BNL). This new event
generator provides a fast, convenient means for producing large numbers of
uncorrelated A+A collision events which can be used for a variety of
applications in STAR, including quality assurance evaluation of event
reconstruction software, determination of detector acceptances and tracking
efficiencies, physics analysis of event-by-event global variables, studies of
strange, rare and exotic particle reconstruction, and so on. The user may
select the number of events, the particle types, the multiplicities, the
one-body momentum space distributions and the detector acceptance ranges. The
various algorithms used in the code and its capabilities are explained.
Additional user information is also discussed. The computer code implementation
is called MEVSIM.

</DOC>
<DOC>
<DOCNO> 119217 </DOCNO>
Fine Structure in the Energy Spectrum of Cosmic Ray Protons at 50 GeV ?


  The recently published precise spectrum of cosmic ray protons from the Alpha
Magnetic Spectrometer has been examined in some detail from the standpoint of a
search for deviations from a smooth, simple, power law. We find a significant
excess ($\simeq$ 10% over $\sim$ 0.3 interval in logE) centered on 50 GeV in
the published data. It is possible that the 'unfolding technique' adopted by
the experimenters causes an overestimate of the excess but it is difficult to
reduce it much below about (5 $\pm$ 3)%.
  We have examined other recent data, too. There is also evidence here, for an
excess in the same energy region, although of only (1.6 $\pm$ 0.9)%. A value of
(3 $\pm$ 1.5)% would be consistent with all the data. There are hints of
similar excesses for heavier nuclei and electrons.
  Possible explanations are put forward for an excess, should it prove to be
genuine.

</DOC>
<DOC>
<DOCNO> 170358 </DOCNO>
Two-state system driven by imperfect pi pulses: an estimate of the error


  The evolution of a two-state system driven by a sequence of imperfect pi
pulses (with random phase or amplitude errors) is calculated. The resulting
decreased fidelity is used to derive a plausible limit on the performance of
"bang-bang" control methods for the suppression of decoherence.

</DOC>
<DOC>
<DOCNO> 8115 </DOCNO>
Advantages and Disadvantages of Layer Growth Model in Which Particles


  In this paper we would like give a short review of our recent works and
current investigation in modeling of solid film surfaces growth based on
computer Monte
 Carlo simulations. We also discuss effect of some simplification in growth
rules on speed-up of computations, and the time evolution of surface morphology
(for example its roughness or anisotropy). We obtained qualitative agreement of
computer simulation with experimental results for homoepitaxially grown simple
metal films.

</DOC>
<DOC>
<DOCNO> 80832 </DOCNO>
Fermion Condensates in Two Colours Finite Density QCD at Strong Coupling


  We study unquenched lattice SU(2) at nonzero chemical potential at strong
coupling and with eight flavours of Kogut-Susskind fermions. Introducing a
diquark source term we analyze the behaviour of different types of fermion
condensates. Using a non standard approach we can obtain results at zero
external source without extrapolations. We find strong evidences for a (high
density) second order phase transition where a diquark condensate appears. The
corresponding critical chemical potential is in good agreement with half the
pion mass.

</DOC>
<DOC>
<DOCNO> 100536 </DOCNO>
Asymptotic behaviour and the moduli space of doubly-periodic instantons


  We study doubly-periodic instantons, i.e. instantons on the product of a
1-dimensional complex torus T with a complex line C, with quadratic curvature
decay. We determine the asymptotic behaviour of these instantons, constructing
new asymptotic invariants. We show that the underlying holomorphic bundle
extends to TxP1. The converse statement is also true, namely a holomorphic
bundle on TxP1 which is flat on the torus at infinity, and satisfies a
stability condition, comes from a doubly-periodic instanton. Finally, we study
the hyperkahler geometry of the moduli space of doubly-periodic instantons, and
prove that the Nahm transform previously defined by the second author is a
hyperkahler isometry with the moduli space of certain meromorphic Higgs bundles
on the dual torus.

</DOC>
<DOC>
<DOCNO> 40346 </DOCNO>
Event shape studies at HERA


  Recent progress on the study of power corrections applied to event shape
variables in deep inelastic ep scattering is discussed.

</DOC>
<DOC>
<DOCNO> 117558 </DOCNO>
A WIMP Detector with Two-Phase Liquid Xenon


  We describe the liquid-xenon dark-matter detector program of the UCLA-Torino
team. A two-phase detector, ZEPLIN II, for the Boulby Mine is a good match for
the current search for WIMP dark matter.

</DOC>
<DOC>
<DOCNO> 39976 </DOCNO>
Collider signals from slow decays in supersymmetric models with an


  The problem of the origin of the mu parameter in the Minimal Supersymmetric
Standard Model can be solved by introducing singlet supermultiplets with
non-renormalizable couplings to the ordinary Higgs supermultiplets. The
Peccei-Quinn symmetry is broken at a scale which is the geometric mean between
the weak scale and the Planck scale, yielding a mu term of the right order of
magnitude and an invisible axion. These models also predict one or more singlet
fermions which have electroweak-scale masses and suppressed couplings to MSSM
states. I consider the case that such a singlet fermion, containing the axino
as an admixture, is the lightest supersymmetric particle. I work out the
relevant couplings in several of the simplest models of this type, and compute
the partial decay widths of the next-to-lightest supersymmetric particle
involving leptons or jets. Although these decays will have an average proper
decay length which is most likely much larger than a typical collider detector,
they can occasionally occur within the detector, providing a striking signal.
With a large sample of supersymmetric events, there will be an opportunity to
observe these decays, and so gain direct information about physics at very high
energy scales.

</DOC>
<DOC>
<DOCNO> 101519 </DOCNO>
On the Hitchin morphism in positive characteristic


  Let X be a smooth projective curve over a field of characteristic p>0. We
show that the Hitchin morphism, which associates to a Higgs bundle its
characteristic polynomial, has a non-trivial deformation over the affine line.
This deformation is constructed by considering the moduli stack of
t-connections on vector bundles on X and an analogue of the p-curvature, and by
observing that the associated characteristic polynomial is, in a suitable
sense, a p-th power.

</DOC>
<DOC>
<DOCNO> 178444 </DOCNO>
Transport Theoretical Approach to the Nucleon Spectral Function in


  The nucleon spectral function in infinite nuclear matter is calculated in a
quantum transport theoretical approach. Exploiting the known relation between
collision rates and correlation functions the spectral function is derived
self-consistently. By re-inserting the spectral functions into the collision
integrals the description of hard processes from the high-momentum components
of wave functions and interactions is improved iteratively until convergence is
achieved. The momentum and energy distributions and the nuclear matter
occupation probabilities are in very good agreement with the results obtained
from many-body theory.

</DOC>
<DOC>
<DOCNO> 83176 </DOCNO>
Representation results for defeasible logic


  The importance of transformations and normal forms in logic programming, and
generally in computer science, is well documented. This paper investigates
transformations and normal forms in the context of Defeasible Logic, a simple
but efficient formalism for nonmonotonic reasoning based on rules and
priorities. The transformations described in this paper have two main benefits:
on one hand they can be used as a theoretical tool that leads to a deeper
understanding of the formalism, and on the other hand they have been used in
the development of an efficient implementation of defeasible logic.

</DOC>
<DOC>
<DOCNO> 121292 </DOCNO>
Variability in LINERs


  A small number of LINERs have been seen to display variable H-alpha emission
with a very broad, double-peaked profile. Recent observations with the Hubble
Space Telescope indicate that such emission may be a common attribute of
LINERs. The double-peaked or double-shouldered line profiles resemble those
found in a subset of broad-line radio galaxies. Several lines of argument
suggest that such features trace an outer thin accretion disk irradiated by an
inner ion torus, in accord with advection-dominated accretion flow (ADAF)
models. Variability monitoring of this broad H-alpha component thus may provide
a means of testing accretion physics on small scales within these sources.

</DOC>
<DOC>
<DOCNO> 10919 </DOCNO>
Super-Calogero-Moser-Sutherland systems and free super-oscillators : a


  We show that the supersymmetric rational Calogero-Moser-Sutherland (CMS)
model of A_{N+1}-type is equivalent to a set of free super-oscillators, through
a similarity transformation. We prescribe methods to construct the complete
eigen-spectrum and the associated eigen-functions, both in supersymmetry
preserving as well as supersymmetry breaking phases, from the free
super-oscillator basis. Further we show that a wide class of super-Hamiltonians
realizing dynamical OSp(2|2) supersymmetry, which also includes all types of
rational super-CMS as a small subset, are equivalent to free super-oscillators.
We study BC_{N+1}-type super-CMS model in some detail to understand the
subtleties involved in this method.

</DOC>
<DOC>
<DOCNO> 80824 </DOCNO>
Odd-flavor Simulations by the Hybrid Monte Carlo


  The standard hybrid Monte Carlo algorithm is known to simulate even flavors
QCD only. Simulations of odd flavors QCD, however, can be also performed in the
framework of the hybrid Monte Carlo algorithm where the inverse of the fermion
matrix is approximated by a polynomial. In this exploratory study we perform
three flavors QCD simulations. We make a comparison of the hybrid Monte Carlo
algorithm and the R-algorithm which also simulates odd flavors systems but has
step-size errors. We find that results from our hybrid Monte Carlo algorithm
are in agreement with those from the R-algorithm obtained at very small
step-size.

</DOC>
<DOC>
<DOCNO> 120678 </DOCNO>
Gravitational Microlensing of Gamma Ray Bursts at Medium Optical Depth


  Gravitational lensing of a gamma ray burst (GRB) by a single point mass will
produce a second, delayed signal. Several authors have discussed using
microlensed GRBs to probe a possible cosmological population of compact
objects. We analyse a closely related phenomenon; the effect of microlensing by
low to medium optical depth in compact objects on the averaged observed
light-curve of a sample of GRBs. We discuss the cumulative measured flux as a
function of time resulting from delays due to microlensing by cosmological
compact objects. The time-scale and curvature of this function describe unique
values for the compact object mass and optical depth. For GRBs with durations
larger than the detector resolution, limits could be placed on the mass and
optical depth of cosmological compact objects. The method does not rely on the
separation of lensed bursts from those which are spatially coincident.

</DOC>
<DOC>
<DOCNO> 8029 </DOCNO>
Decay channels and appearance sizes of doubly anionic gold and silver


  Second electron affinities of Au_N and Ag_N clusters and the dissociation
energies for fission of the Au_N^{2-} and Ag_N^{2-} dianions are calculated
using the finite-temperature shell-correction method and allowing for triaxial
deformations. Dianionic clusters with N > 2 are found to be energetically
stable against fission, leaving electron autodetachment as the dominant decay
process. The second electron affinities exhibit pronounced shell effects in
excellent agreement with measured abundance spectra for Au_N^{2-} (N < 30),
with appearance sizes N=12 for gold dianionic clusters and N=24 for silver
dianionic clusters.

</DOC>
<DOC>
<DOCNO> 83488 </DOCNO>
Available Stabilizing Heaps


  This paper describes a heap construction that supports insert and delete
operations in arbitrary (possibly illegitimate) states. After any sequence of
at most O(m) heap operations, the heap state is guarantee to be legitimate,
where m is the initial number of items in the heap. The response from each
operation is consistent with its effect on the data structure, even for
illegitimate states. The time complexity of each operation is O(lg K) where K
is the capacity of the data structure; when the heap's state is legitimate the
time complexity is O(lg n) for n equal to the number items in the heap.

</DOC>
<DOC>
<DOCNO> 116416 </DOCNO>
Classical "Dressing" of a Free Electron in a Plane Electromagnetic Wave


  The energy and momentum densities of the fields of a free electron in a plane
electromagnetic wave include interference terms that are the classical version
of the ``dressing'' of the electron the arises in a quantum analysis. The
transverse mechanical momentum of the oscillating electron is balanced by the
field momentum resulting from the interference between the driving wave and the
static part of the electron's field. The interference between the wave and the
oscillating part of the electron's field leads to a longitudinal field momentum
and a negative field energy that compensate for the longitudinal momentum and
kinetic energy of the electron. The interference terms are dominated by the
near zone, so that as the wave passes the electron by the latter reverts to its
energy and momentum prior to the arrival of the wave.

</DOC>
<DOC>
<DOCNO> 70104 </DOCNO>
Neutrino masses and the baryon asymmetry


  Due to sphaleron processes in the high-temperature symmetric phase of the
standard model the cosmological baryon asymmetry is related to neutrino
properties. For hierarchical neutrino masses, with $B-L$ broken at the
unification scale $\Lambda_{GUT}\sim 10^{16} $GeV, the observed baryon
asymmetry $n_B/s \sim 10^{-10}$ can be naturally explained by the decay of
heavy Majorana neutrinos. We illustrate this mechanism with two models of
neutrino masses, consistent with the solar and atmospheric neutrino anomalies,
which are based on the two symmetry groups $SU(5)\times U(1)_F$ and
$SU(3)_c\times SU(3)_L\times SU(3)_R\times U(1)_F$.
  We also review related cosmological bounds on Majorana neutrino masses and
the use of Boltzmann equations.

</DOC>
<DOC>
<DOCNO> 84459 </DOCNO>
The Rest-Frame Instant Form of Relativistic Perfect Fluids and of


  For perfect fluids with equation of state $\rho = \rho (n,s)$, Brown gave an
action principle depending only on their Lagrange coordinates $\alpha^i(x)$
without Clebsch potentials. After a reformulation on arbitrary spacelike
hypersurfaces in Minkowski spacetime, the Wigner-covariant rest-frame instant
form of these perfect fluids is given. Their Hamiltonian invariant mass can be
given in closed form for the dust and the photon gas. The action for the
coupling to tetrad gravity is given. Dixon's multipoles for the perfect fluids
are studied on the rest-frame Wigner hyperplane. It is also shown that the same
formalism can be applied to non-dissipative relativistic elastic materials
described in terms of Lagrangian coordinates.

</DOC>
<DOC>
<DOCNO> 117642 </DOCNO>
ROSAT Evidence for Intrinsic Oxygen Absorption in Cooling Flow Galaxies


  Using spatially resolved, deprojected ROSAT PSPC spectra of 10 of the
brightest cooling flow galaxies and groups with low Galactic column densities
we have detected intrinsic absorption over energies ~0.4-0.8 keV in half of the
sample. Since no intrinsic absorption is indicated for energies below ~0.4 keV,
the most reasonable model for the absorber is collisionally ionized gas at
temperatures T=10^{5-6} K with most of the absorption arising from ionized
states of oxygen but with a significant contribution from carbon and nitrogen.
The soft X-ray emission of this warm gas can explain the sub-Galactic column
densities of cold gas inferred within the central regions of most of the
systems. Attributing the absorption to ionized gas reconciles the large columns
of cold H and He inferred from EINSTEIN and ASCA with the lack of such columns
inferred from ROSAT. Within the central ~10-20 kpc, where the constraints are
most secure, the estimated mass of the ionized absorber is consistent with most
(perhaps all) of the matter deposited by a cooling flow over the lifetime of
the flow. Since the warm absorber produces no significant H or He absorption
the large absorber masses are consistent with the negligible atomic and
molecular H inferred from HI and CO observations of cooling flows. It is also
found that if T > ~2x10^5 K then the optical and UV emission implied by the
warm gas does not violate published constraints. Finally, we discuss how the
prediction of warm ionized gas as the product of mass drop-out in these and
other cooling flows can be verified with new CHANDRA and XMM observations.
(Abridged)

</DOC>
<DOC>
<DOCNO> 116601 </DOCNO>
Geometry of River Networks I: Scaling, Fluctuations, and Deviations


  This article is the first in a series of three papers investigating the
detailed geometry of river networks. Large-scale river networks mark an
important class of two-dimensional branching networks, being not only of
intrinsic interest but also a pervasive natural phenomenon. In the description
of river network structure, scaling laws are uniformly observed. Reported
values of scaling exponents vary suggesting that no unique set of scaling
exponents exists. To improve this current understanding of scaling in river
networks and to provide a fuller description of branching network structure, we
report here a theoretical and empirical study of fluctuations about and
deviations from scaling. We examine data for continent-scale river networks
such as the Mississippi and the Amazon and draw inspiration from a simple model
of directed, random networks. We center our investigations on the scaling of
the length of sub-basin's dominant stream with its area, a characterization of
basin shape known as Hack's law. We generalize this relationship to a joint
probability density and show that fluctuations about scaling are substantial.
We find strong deviations from scaling at small scales which can be explained
by the existence of linear network structure. At intermediate scales, we find
slow drifts in exponent values indicating that scaling is only approximately
obeyed and that universality remains indeterminate. At large scales, we observe
a breakdown in scaling due to decreasing sample space and correlations with
overall basin shape. The extent of approximate scaling is significantly
restricted by these deviations and will not be improved by increases in network
resolution.

</DOC>
<DOC>
<DOCNO> 71118 </DOCNO>
Enhancement of $\epsilon'/\epsilon$ in the SU(2)$_L \timesSU(2)_R


  We explore the possible enhancement of direct CP violating parameter $\epe$
in the general left-right model based on the SU(2)$_L \timesSU(2)_R \times$U(1)
gauge group. The mixing matrix of right-handed quarks, $V_{CKM}^R$ is
observable in the left-right model, and provides new source of CP violating
phase. We calculate the parameter $\epe$ in the left-right model and show that
the new phases from $V_{CKM}^R$ can yield the sizable contribution to the
direct CP violation enough to satisfy the recent measurements of Re$(\epe)$
from Fermilab KTeV and CERN NA48 experiments.

</DOC>
<DOC>
<DOCNO> 119009 </DOCNO>
Is a Simple Collisionless Relic Dark Matter Particle Ruled Out?


  The central densities of dark matter (DM) halos are much lower than predicted
in cold DM models of structure formation. Confirmation that they have cores
with a finite central density would allow us to rule out many popular types of
collisionless particle as candidates for DM. Any model that leads to cusped
halos (such as cold DM) is already facing serious difficulties on small scales
and hot DM models have been excluded. Here I show that fermionic warm DM is
inconsistent with the wide range of phase space densities in the DM halos of
well-observed nearby galaxies.

</DOC>
<DOC>
<DOCNO> 116592 </DOCNO>
Off-Diagonal Hyperfine Interaction and Parity Non-conservation in Cesium


  We have performed relativistic many-body calculations of the hyperfine
interaction in the $6s$ and $7s$ states of Cs, including the off-diagonal
matrix element. The calculations were used to determine the accuracy of the
semi-empirical formula for the electromagnetic transition amplitude
$<6s|M1|7s>$ induced by the hyperfine interaction. We have found that even
though the contribution of the many-body effects into the matrix elements is
very large, the square root formula $<6s|H_{hfs}|7s > = \sqrt{< 6s|H_{hfs}|6s >
< 7s|H_{hfs}|7s >}$ remains valid to the accuracy of a fraction of $10^{-3}$.
The result for the M1-amplitude is used in the interpretation of the
parity-violation measurement in the $6s-7s$ transition in Cs which claims a
possible deviation from the Standard model.

</DOC>
<DOC>
<DOCNO> 101082 </DOCNO>
The join of algebraic curves


  Let X,Y be algebraic curves in P^n over C. We give an effective description
of the join J(X,Y)\in P^n of X and Y in terms of local parametrizations of X
and Y.

</DOC>
<DOC>
<DOCNO> 69398 </DOCNO>
Localized (Super)Gravity and Cosmological Constant


  We consider localization of gravity in domain wall solutions of Einstein's
gravity coupled to a scalar field with a generic potential. We discuss
conditions on the scalar potential such that domain wall solutions are
non-singular. Such solutions even exist for appropriate potentials which have
no minima at all and are unbounded below. Domain walls of this type have
infinite tension, while usual kink type of solutions interpolating between two
AdS minima have finite tension. Non-singular domain walls with infinite tension
might a priori avoid recent ``no-go'' theorems indicating impossibility of
supersymmetric embedding of kink type of domain walls in gauged supergravity.
We argue that (non-singular) domain walls are stable even if they have infinite
tension. This is essentially due to the fact that localization of gravity in
smooth domain walls is a Higgs mechanism corresponding to a spontaneous
breakdown of translational invariance. We point out that if the scalar
potential has no minima and approaches finite negative values at infinity, then
higher derivative terms are under control, and do not affect the cosmological
constant on the brane which is vanishing for such backgrounds. Nonetheless, we
also point out that higher curvature terms generically delocalize gravity, so
that the desired lower dimensional Newton's law is no longer reproduced.

</DOC>
<DOC>
<DOCNO> 69986 </DOCNO>
Quantum effects for the neutrino mixing matrix in the democratic-type


  We investigate the quantum effects for the democratic-type neutrino mass
matrix given at the right-handed neutrino mass scale $m_R$ in order to see (i)
whether $\theta_{23}=-\pi/4$ predicted by the model is stable to explain the
atmospheric neutrino anomaly, (ii) how $\theta_{12}$ and $\theta_{13}$ behave,
and (iii) whether the predicted Dirac CP phase $\delta$ keeps maximal size, at
the weak scale $m_Z$. We find that, for the (inversely) hierarchical mass
spectrum with $m_1\sim m_2$, $\theta_{23}$ and $\theta_{13}$ are stable, while
$\theta_{12}$ is not so, which leads to the possibility that the solar neutrino
mixing angle can become large at $m_Z$ even if it is taken small at $m_R$. We
also show that $\delta$ keeps almost maximal for the above mass spectrum, and
our model can give the large CP violation effect in the future neutrino
oscillation experiments if the solar neutrino puzzle is explained by the large
mixing angle MSW solution.

</DOC>
<DOC>
<DOCNO> 72006 </DOCNO>
W-Pair Production with YFSWW/KoralW


  A theoretical description of W-pair production in terms of two complementary
Monte Carlo event generators YFSWWand KoralW is presented. The way to combine
the results of these two programs in order to get precise predictions for WW
physics at LEP2 and LC energies is discussed.

</DOC>
<DOC>
<DOCNO> 170793 </DOCNO>
Superluminal Motion in The interacting System of Electrons, Positrons


  The coupled system of Boltzman equations for the interacting system of
electrons, positrons and photons in high external electric, E, and arbitrary
magnetic, H, fields is solved. The consideration is made under the conditions
of arbitrary heating and the mutual drag of carriers and photons. The
non-stationary and non-uniform distribution function of photons for the all
considered cases is obtained. It is shown that the distribution function of
photons has the stationary limit for the drift velocities $(\vec{u}\vec{q}/
\hbar \omega_q) <1 $ and grows exponentially with time for the drift velocities
$(\vec{u}\vec{q}/ \hbar \omega_q) \geq 1$. As a result of the analyses of the
phenomena of coupling of the mutual drag system of carriers with the photons,
we obtained some fundamental results: {\bf a)} the finiteness of the mass of
photon (i.e. the rest mass of the photons is not zero); {\bf b)} reality of
tachyons as a quasi-particles with a real mass in amplifying system (or
regime); {\bf c)} the mechanism of the theory of relativity and that of the
Doppler effect which coincides with the renormalization of frequency or mass as
a result of the mutual drag of carriers and photons at external field (force)
are the same. These conclusions were obtained as a result of the fact that the
relativistic factor enters the expressions of the distribution function of
photons and other physical expressions in the first order in the form
$[1-(u^2/c^2) ]^{-1}$, but not in the form $[1-(u^2/c^2) ]^{-1/2}$ as in
Einstein's theory. Also it is shown that the velocity of light is an average
velocity of photons in the ground state.

</DOC>
<DOC>
<DOCNO> 69333 </DOCNO>
Reconciliation of the Measurement of Parity-Nonconservation in Cs with


  Contributions from the Breit interaction in atomic-structure calculations
account for 1.3sigma of the previously reported 2.5sigma deviation from the
Standard Model in the 133Cs weak charge [S.C. Bennett and C.E. Wieman, Phys.
Rev. Lett. 82, 2484 (1999)]. The updated corrections for the neutron
distribution reduce the discrepancy further to 1.0sigma. The updated value of
the weak charge is Q_W(133Cs) = -72.65(28)_{expt}(34)_{theor}.
  The present analysis is a higher-order extension of previous calculation [A.
Derevianko, E-print physics/0001046].

</DOC>
<DOC>
<DOCNO> 85358 </DOCNO>
2d quantum gravity with torsion, dilaton theory and black hole formation


  Starting from the work of the author in 1990 with different collaborators,
essential progress in 2d gravity theories has been made. Now all such theories
(and not only certain special models) can be treated at the classical as well
as at the quantum level. New physical insights have been obtained, as e.g. the
``virtual black hole''. The formalism developed in this context recently also
finds increasing interest in mathematical physics.

</DOC>
<DOC>
<DOCNO> 67693 </DOCNO>
Electroweak Phase Transition in the MSSM: 4-Dimensional Lattice


  Recent lattice results have shown that there is no Standard Model (SM)
electroweak phase transition (EWPT) for Higgs boson masses above \approx 72
GeV, which is below the present experimental limit. According to perturbation
theory and 3-dimensional (3d) lattice simulations there could be an EWPT in the
Minimal Supersymmetric Standard Model (MSSM) that is strong enough for
baryogenesis up to m_h \approx 105 GeV. In this letter we present the results
of our large scale 4-dimensional (4d) lattice simulations for the MSSM EWPT. We
carried out infinite volume and continuum limits and found a transition whose
strength agrees well with perturbation theory, allowing MSSM electroweak
baryogenesis at least up to m_h = 103 \pm 4 GeV. We determined the properties
of the bubble wall that are important for a successful baryogenesis.

</DOC>
<DOC>
<DOCNO> 101230 </DOCNO>
Algebraic estimates, stability of local zeta functions, and uniform


  A method of ``algebraic estimates'' is developed, and used to study the
stability properties of integrals of the form \int_B|f(z)|^{-\d}dV, under
small deformations of the function f. The estimates are described in terms of
a stratification of the space of functions \{R(z)=|P(z)|^{\e}/|Q(z)|^{\d}\} by
algebraic varieties, on each of which the size of the integral of R(z) is
given by an explicit algebraic expression. The method gives an independent
proof of a result on stability of Tian in 2 dimensions, as well as a partial
extension of this result to 3 dimensions. In arbitrary dimensions, combined
with a key lemma of Siu, it establishes the continuity of the mapping c\ra
\int_B|f(z,c)|^{-\d}dV_1\cdots dV_n when f(z,c) is a holomorphic function of
(z,c). In particular the leading pole is semicontinuous in f, strengthening
also an earlier result of Lichtin.

</DOC>
<DOC>
<DOCNO> 11188 </DOCNO>
Density fluctuations and multifragmentation of nuclear matter


  The density fluctuations of nuclear matter are studied within a mean-field
model in wich fluctuations are generated by an external stochastic field. The
constraints imposed on the random force by the fluctuation-dissipation theorem
are analyzed. It is shown that in the proximity of the borders of the spinodal
region the assumption of a white-noise stochastic field can be reliably used.
The domain distribution of the liquid phase in the spinodal decomposition of
nuclear matter is derived. The related distribution of fragment sizes compares
favourably with the experimental fragment distribution observed in heavy ion
collisions.

</DOC>
<DOC>
<DOCNO> 151735 </DOCNO>
Induced Field Theory on the Brane World - Gravity, Extrinsic Curvature,


  We show how the gravity, extrinsic curvature, and gauge field theories are
induced on dynamically localized brane world. They should obey the
Gauss-Codazzi-Ricci equation in addition to their own equations of motion. As
an example, we derive the solitonic solution for curved domain wall in five
dimensions in terms of gravity and extrinsic curvature fields of the brane, and
then derive the effective action for their field theory on the brane.

</DOC>
<DOC>
<DOCNO> 68661 </DOCNO>
Deriving effective transport equations for non-Abelian plasmas


  Within classical transport theory, an approach is presented to derive
systematically effective collision terms and noise sources for effective
kinetic equations of non-Abelian plasmas. This procedure amounts to the
`integrating-out' of fluctuations, and is applicable for in- and
out-of-equilibrium situations. When applied to a hot non-Abelian plasma close
to equilibrium we recover the collision integral and the noise source first
obtained by B\"odeker. It is also shown that our approach, and hence
B\"odeker's effective theory, is consistent with the fluctuation-dissipation
theorem.

</DOC>
<DOC>
<DOCNO> 9579 </DOCNO>
Excitation spectrum of three dressed Bose-Einstein condensates


  We study quantum dynamics of three dressed Bose-Einstein condensates in a
high-Q cavity. The quasiparticle excitation spectrum of this system is found
numerically.
  The stability of the quasiparticle excitation is analyzed. It is shown that
there exist instabilities in the excitation spectrum.

</DOC>
<DOC>
<DOCNO> 13725 </DOCNO>
Self-Consistent Calculation of Total Energies of the Electron Gas Using


  The performance of many-body perturbation theory for calculating ground-state
properties is investigated. We present fully numerical results for the electron
gas in three and two dimensions in the framework of the GW approximation. The
overall agreement with very accurate Monte Carlo data is excellent, even for
those ranges of densities for which the GW approach is often supposed to be
unsuitable. The latter seems to be due to the fulfilment of general
conservation rules. These results open further prospects for accurate
calculations of ground-state properties circumventing the limitations of
standard density functional theory.

</DOC>
<DOC>
<DOCNO> 68468 </DOCNO>
Is the polarized light flavor sea-quark asymmetric?


  Simple formulas on $\Delta\bar d(x)-\Delta\bar u(x)$ are proposed for
extracting their values from polarized deep-inelastic semi-inclusive data. The
present SMC and HERMES data suggest that $\Delta\bar d(x)-\Delta\bar u(x)$ is
slightly negative, though the precision of the data is not enough for
confirming it.

</DOC>
<DOC>
<DOCNO> 101222 </DOCNO>
Isocategorical groups


  It is well known that if two finite groups have the same symmetric tensor
categories of representations over C, then they are isomorphic. We study the
following question: when do two finite groups G1,G2 have the same tensor
categories of representations over C (without regard for the commutativity
constraint). We call two groups with such property isocategorical. We give an
example of two groups which are isocategorical but not isomorphic: the affine
symplectic group of a vector space over the field of two elements, and an
appropriate "affine pseudosymplectic group" introduced by R.Griess (containing
the "pseudosymplectic group" of A.Weil). On the other hand, we give a
classification of groups isocategorical to a given group. In particular, we
show that if G has no nontrivial normal subgroups of order 2^{2m} then any
group isocategorical to G must actually be isomorphic to G. The proofs use the
theory of triangular Hopf algebras. We also apply the notion of isocategorical
groups to studying the question: when are two triangular semisimple Hopf
algebras isomorphic as Hopf algebras?

</DOC>
<DOC>
<DOCNO> 68204 </DOCNO>
Bound on the tau neutrino magnetic moment from the TRISTAN experiments


  We set limits on the magnetic moment and charge radius of the tau neutrino by
examining an extra contribution to the electroweak process $e^+ e^- \to \nu
\bar{\nu}\gamma$ using VENUS, TOPAZ and AMY results. We find that
$\kappa(\nu_{\tau}) < 9.1\times{10}^{-6}$
  (i.e. $\mu(\nu_{\tau}) < 9.1\times{10}^{-6}\mu_B, \mu_B = e/2m_e$) and $<r^2
> < 3.1\times{10}^{-31}$cm$^2$ with Poisson statistics by combining their
results. Whereas, similar to this method, with the Unified Approach we find
that $\kappa(\nu_{\tau}) < 8.0\times{10}^{-6}$ and $<r^2 > <
2.7\times{10}^{-31}$cm$^2$.

</DOC>
<DOC>
<DOCNO> 117780 </DOCNO>
Investigations of the Local Supercluster Velocity Field III. Tracing the


  We have extended the discussion of Paper II (Ekholm et al. 1999) to cover
also the backside of the Local Supercluster (LSC) by using 96 galaxies within
Theta<30 deg from the adopted centre of LSC and with distance moduli from the
direct B-band Tully-Fisher relation. In order to minimize the influence of the
Malmquist bias we required log V_max>2.1 and sigma_{B_T}<0.2 mag.
  We found out that if R_Virgo<20 Mpc this sample fails to follow the expected
dynamical pattern from the Tolman-Bondi (TB) model. When we compared our
results with the Virgo core galaxies given by Federspiel et al. (1998) we were
able to constrain the distance to Virgo: R_Virgo=20-24 Mpc.
  When analyzing the TB-behaviour of the sample as seen from the origin of the
metric as well as that with distances from the extragalactic Cepheid
PL-relation we found additional support to the estimate R_Virgo=21 Mpc given in
Paper II. Using a two-component mass-model we found a Virgo mass estimate
M_Virgo= (1.5-2)M_virial, where M_virial=9.375.10^14M_sun for R_Virgo=21 Mpc.
This estimate agrees with the conclusion in Paper I (Teerikorpi et al. 1992).
  Our results indicate that the density distribution of luminous matter is
shallower than that of the total gravitating matter when q_0<=0.5. The
preferred exponent in the density power law, alpha\approx2.5, agrees with
recent theoretical work on the universal density profile of dark matter
clustering in an Einstein-deSitter universe (Tittley & Couchman 1999).

</DOC>
<DOC>
<DOCNO> 8876 </DOCNO>
Crystal Structure and Physical Properties of U3T3Sn4 (T = Ni, Cu)


  Heat capacity experiments, crystal structure determination and transmission
electron microscopy have been carried out on U3Cu3Sn4 single-crystals. U3Cu3Sn4
was confirmed to be a heavy-fermion antiferromagnet (TN=13(1) K) with a low
temperature electronic heat capacity coefficient gamma=390 mJ/molUK2. Low
temperature heat capacity experiments on a U3Ni3Sn4 single-crystal indicate
that below 0.4 K there is a crossover between the previously observed non-Fermi
liquid behavior and a Fermi liquid state.

</DOC>
<DOC>
<DOCNO> 11783 </DOCNO>
Longitudinal Field Influence on the Phase Transition and Physical


  We verify whether the previously developed model of a KD2PO4 crystal, with
the shear strain eps6 taken into account, is able to describe the longitudinal
electric field E3 influence on the KH2PO4 family ferroelectrics. Major effects
of the strain eps6 are splitting of the Slater energies of the short-range
correlations and the effective field created by piezoelectric coupling.
Calculated TC-E3 phase diagrams, field dependences of polarization,
susceptibility, and elastic constant of deuterated KD2PO4 and pure KH2PO4 well
accord with the available experimental data. For a consistent description of
all dielectric and piezoelectric characteristics of the crystals, phonon
degrees of freedom must be taken into account.

</DOC>
<DOC>
<DOCNO> 9093 </DOCNO>
Numerical simulations of directed sandpile models


  Directed sandpile models with different toppling rules are studied by means
of numerical simulations in two dimensions, with the purpose of determining the
different universality classes. It is concluded that the random-threshold
directed model is in the same universality of the Manna directed model where
multiple toppling events plays a determinant role. The BTW model with uniform
and noisy driving are found to display the same critical behavior. Moreover it
is observed that the Zhang model does not satisfy simple finite size scaling.

</DOC>
<DOC>
<DOCNO> 118327 </DOCNO>
Decay of proton into Planck neutrino in the theory of gravity


  It is considered gravitational interaction within the framework of the Newton
theory and the quantum field theory. It is introduced the Planck neutrino
$\nu_{Pl}$. Gravitational interaction of the fields $\psi\psi$ includes
short-range interaction $\psi\nu_{Pl}$ and long-range interaction
$\nu_{Pl}\nu_{Pl}$. Gravitational radiation can be identified with the Planck
neutrino. The theory predicts the decay of proton into Planck neutrino. It is
assumed that the Planck mass built from three fundamental constants $\hbar$,
$c$ and $G$ is fixed in all the inertial frames. This leads to that the
lifetime of proton relative to the decay into Planck neutrino decreases with
the Lorentz factor as $\sim \gamma^{-5}$. Such a dependence of the lifetime of
proton on the Lorentz factor yields a cut-off in the EHECRs spectrum. It is
shown that the first "knee" in the EHECRs spectrum $E\sim 3\times 10^{15}$ eV
corresponds to the lifetime of proton equal to the lifetime of the universe,
the second "knee" $E\sim 10^{17}-10^{18}$ eV corresponds to the lifetime of
proton equal to the thickness of our galactic disc. The EHECRs with the
energies $E>3 \times 10^{18}$ eV can be identified with the Planck neutrinos.

</DOC>
<DOC>
<DOCNO> 116315 </DOCNO>
The singular points of Einstein's Universe


  Short note by Marcel Brillouin on the representation of the mass point in
general relativity.

</DOC>
<DOC>
<DOCNO> 123138 </DOCNO>
The Power Spectrum Dependence of Dark Matter Halo Concentrations


  High-resolution N-body simulations are used to examine the power spectrum
dependence of the concentration of galaxy-sized dark matter halos. It is found
that dark halo concentrations depend on the amplitude of mass fluctuations as
well as on the ratio of power between small and virial mass scales. This
finding is consistent with the original results of Navarro, Frenk & White
(NFW), and allows their model to be extended to include power spectra
substantially different from Cold Dark Matter (CDM). In particular, the
single-parameter model presented here fits the concentration dependence on halo
mass for truncated power spectra, such as those expected in the warm dark
matter scenario, and predicts a stronger redshift dependence for the
concentration of CDM halos than proposed by NFW. The latter conclusion confirms
recent suggestions by Bullock et al., although this new modeling differs from
theirs in detail. These findings imply that observational limits on the
concentration, such as those provided by estimates of the dark matter content
within individual galaxies, may be used to constrain the amplitude of mass
fluctuations on galactic and subgalactic scales. The constraints on
$\Lambda$CDM models posed by the dark mass within the solar circle in the Milky
Way and by the zero-point of the Tully-Fisher relation are revisited, with the
result that neither dataset is clearly incompatible with the `concordance'
($\Omega_0=0.3$, $\Lambda_0=0.7$, $\sigma_8=0.9$) $\Lambda$CDM cosmogony. This
conclusion differs from that reached recently by Navarro & Steinmetz, a
disagreement that can be traced to inconsistencies in the normalization of the
$\Lambda$CDM power spectrum used in that work.

</DOC>
<DOC>
<DOCNO> 10981 </DOCNO>
Renormalization Group Analysis of a Quivering String Model of Posture


  Scaling concepts and renormalization group (RG) methods are applied to a
simple linear model of human posture control consisting of a trembling or
quivering string subject to damping and restoring forces. The string is driven
by uncorrelated white Gaussian noise intended to model the corrections of the
physiological control system. We find that adding a weak quadratic nonlinearity
to the posture control model opens up a rich and complicated phase space
(representing the dynamics) with various non-trivial fixed points and basins of
attraction. The transition from diffusive to saturated regimes of the linear
model is understood as a crossover phenomenon, and the robustness of the linear
model with respect to weak non-linearities is confirmed. Correlations in
posture fluctuations are obtained in both the time and space domain. There is
an attractive fixed point identified with falling. The scaling of the
correlations in the front-back displacement, which can be measured in the
laboratory, is predicted for both the large-separation (along the string) and
long-time regimes of posture control.

</DOC>
<DOC>
<DOCNO> 151040 </DOCNO>
BFT embedding of noncommutative D-brane system


  We study noncommutative geometry in the framework of the
Batalin-Fradkin-Tyutin(BFT) scheme, which converts second class constraint
system into first class one. In an open string theory noncommutative geometry
appears due to the mixed boundary conditions having second class constraints,
which arise in string theory with $D$-branes under a constant Neveu-Schwarz
$B$-field. Introduction of a new coordinate $y$ on $D$-brane through BFT
analysis allows us to obtain the commutative geometry with the help of the
first class constraints, and the resulting action corresponding to the first
class Hamiltonian in the BFT Hamiltonian formalism has a new local symmetry.

</DOC>
<DOC>
<DOCNO> 69661 </DOCNO>
Resumming the large-N approximation for time evolving quantum systems


  In this paper we discuss two methods of resumming the leading and next to
leading order in 1/N diagrams for the quartic O(N) model. These two approaches
have the property that they preserve both boundedness and positivity for
expectation values of operators in our numerical simulations. These
approximations can be understood either in terms of a truncation to the
infinitely coupled Schwinger-Dyson hierarchy of equations, or by choosing a
particular two-particle irreducible vacuum energy graph in the effective action
of the Cornwall-Jackiw-Tomboulis formalism. We confine our discussion to the
case of quantum mechanics where the Lagrangian is $L(x,\dot{x}) = (1/2)
\sum_{i=1}^{N} \dot{x}_i^2 - (g/8N) [ \sum_{i=1}^{N} x_i^2 - r_0^2 ]^{2}$. The
key to these approximations is to treat both the $x$ propagator and the $x^2$
propagator on similar footing which leads to a theory whose graphs have the
same topology as QED with the $x^2$ propagator playing the role of the photon.
The bare vertex approximation is obtained by replacing the exact vertex
function by the bare one in the exact Schwinger-Dyson equations for the one and
two point functions. The second approximation, which we call the dynamic Debye
screening approximation, makes the further approximation of replacing the exact
$x^2$ propagator by its value at leading order in the 1/N expansion. These two
approximations are compared with exact numerical simulations for the quantum
roll problem. The bare vertex approximation captures the physics at large and
modest $N$ better than the dynamic Debye screening approximation.

</DOC>
<DOC>
<DOCNO> 116476 </DOCNO>
Coupled Two-Way Clustering Analysis of Gene Microarray Data


  We present a novel coupled two-way clustering approach to gene microarray
data analysis. The main idea is to identify subsets of the genes and samples,
such that when one of these is used to cluster the other, stable and
significant partitions emerge. The search for such subsets is a computationally
complex task: we present an algorithm, based on iterative clustering, which
performs such a search. This analysis is especially suitable for gene
microarray data, where the contributions of a variety of biological mechanisms
to the gene expression levels are entangled in a large body of experimental
data. The method was applied to two gene microarray data sets, on colon cancer
and leukemia. By identifying relevant subsets of the data and focusing on them
we were able to discover partitions and correlations that were masked and
hidden when the full dataset was used in the analysis. Some of these partitions
have clear biological interpretation; others can serve to identify possible
directions for future research.

</DOC>
<DOC>
<DOCNO> 99466 </DOCNO>
Differential Equations Compatible with KZ Equations


  We define a system of "dynamical" differential equations compatible with the
KZ differential equations. The KZ differential equations are associated to a
complex simple Lie algebra $\mathbf{g}$. These are equations on a function of
$n$ complex variables $z_i$ taking values in the tensor product of $n$ finite
dimensional $\mathbf{g}$-modules. The KZ equations depend on the "dual"
variable in the Cartan subalgebra of $\mathbf{g}$. The dynamical differential
equations are differential equations with respect to the dual variable. We
prove that the standard hypergeometric solutions of the KZ equations also
satisfy the dynamical equations. As an application we give a new determinant
formula for the coordinates of a basis of hypergeometric solutions.

</DOC>
<DOC>
<DOCNO> 71650 </DOCNO>
Lorentz Invariant Baryon CHPT


  Using the example of the elastic $\pi N$-amplitude, we discuss the low energy
expansion of QCD amplitudes in the sector with baryon number one. We show that
the chiral expansion of these amplitudes breaks down in certain regions of
phase space and present a framework which leads to a coherent description
throughout the low energy region, while keeping Lorentz and chiral invariance
manifest at every stage of the calculation. We explain how to construct a
representation of the pion nucleon scattering amplitude in terms of functions
of a single variable, which is valid to $O(q^4)$ and properly accounts for the
$\pi\pi$- and $\pi N$-cuts required by unitarity.

</DOC>
<DOC>
<DOCNO> 100305 </DOCNO>
Some results of regularity for Severi varieties of projective surfaces


  For a linear system $|C|$ on a smooth projective surface $S$, whose general
element is a smooth, irreducible curve, the Severi variety $V_{|C|, \delta}$ is
the locally closed subscheme of $|C|$ which parametrizes irreducible curves
with only $\delta$ nodes as singularities. In this paper we give numerical
conditions on the class of divisors and upper-bounds on $\delta$ ensuring that
the corresponding Severi variety is everywhere smooth of codimension $\delta$
in $|C|$ (regular, for short). In particular, we focus on surfaces of general
type, since for such surfaces less is known than what is proven for other
cases. Our result generalizes some results of Chiantini-Sernesi (1997) and of
Greuel-Lossen-Shustin (1997 - in the case of nodes) as it is shown by some
examples of Severi varieties on blown-up surfaces or surfaces in $\P^3$ which
are elements of a component of the Noether-Lefschetz locus. We also consider
examples of regular Severi varieties on surfaces in $\P^3$ of general type
which contain a line.

</DOC>
<DOC>
<DOCNO> 83274 </DOCNO>
A Comparison of the XTAG and CLE Grammars for English


  When people develop something intended as a large broad-coverage grammar,
they usually have a more specific goal in mind. Sometimes this goal is covering
a corpus; sometimes the developers have theoretical ideas they wish to
investigate; most often, work is driven by a combination of these two main
types of goal. What tends to happen after a while is that the community of
people working with the grammar starts thinking of some phenomena as
``central'', and makes serious efforts to deal with them; other phenomena are
labelled ``marginal'', and ignored. Before long, the distinction between
``central'' and ``marginal'' becomes so ingrained that it is automatic, and
people virtually stop thinking about the ``marginal'' phenomena. In practice,
the only way to bring the marginal things back into focus is to look at what
other people are doing and compare it with one's own work. In this paper, we
will take two large grammars, XTAG and the CLE, and examine each of them from
the other's point of view. We will find in both cases not only that important
things are missing, but that the perspective offered by the other grammar
suggests simple and practical ways of filling in the holes. It turns out that
there is a pleasing symmetry to the picture. XTAG has a very good treatment of
complement structure, which the CLE to some extent lacks; conversely, the CLE
offers a powerful and general account of adjuncts, which the XTAG grammar does
not fully duplicate. If we examine the way in which each grammar does the thing
it is good at, we find that the relevant methods are quite easy to port to the
other framework, and in fact only involve generalization and systematization of
existing mechanisms.

</DOC>
<DOC>
<DOCNO> 68748 </DOCNO>
Chern-Simons Reduction and non-Abelian Fluid Mechanics


  We propose a non-Abelian generalization of the Clebsch parameterization for a
vector in three dimensions. The construction is based on a group-theoretical
reduction of the Chern-Simons form on a symmetric space. The formalism is then
used to give a canonical (symplectic) discussion of non-Abelian fluid
mechanics, analogous to the way the Abelian Clebsch parameterization allows a
canonical description of conventional fluid mechanics.

</DOC>
<DOC>
<DOCNO> 100076 </DOCNO>
Cohomology of congruence subgroups of SL(4,Z)


  Let $N>1$ be an integer, and let $\Gamma = \Gamma_0 (N) \subset \SL_4 (\Z)$
be the subgroup of matrices with bottom row congruent to $(0,0,0,*)\mod N$. We
compute $H^5 (\Gamma; \C) $ for a range of $N$, and compute the action of some
Hecke operators on many of these groups. We relate the classes we find to
classes coming from the boundary of the Borel-Serre compactification, to
Eisenstein series, and to classical holomorphic modular forms of weights 2 and
4.

</DOC>
<DOC>
<DOCNO> 121862 </DOCNO>
Probing the End of the Dark Ages


  In currently popular cosmological scenarios -- all variants of the cold dark
matter (CDM) cosmogony -- some time beyond a redshift of 15, stars within the
numerous small halos that condense with virial temperatures ~1e4 K created the
first heavy elements; these protogalactic systems, together perhaps with an
early population of mini-quasars, generated the ultraviolet radiation and
mechanical energy that reheated and reionized the cosmos. The history of the
Universe during and soon after these crucial formative stages is recorded in
the thermal, ionization, and chemical state of the all-pervading intergalactic
medium (IGM), which contains most of the ordinary baryonic material left over
from the big bang. Throughout the epoch of structure formation, the IGM becomes
clumpy under the influence of gravity, and acts as a source for the gas that
gets accreted, cools, and forms stars within subgalactic fragments, and as a
sink for the metal enriched material, energy, and radiation which they eject.

</DOC>
<DOC>
<DOCNO> 100513 </DOCNO>
Regular coverings in filter and ideal lattices


  The Dedekind-Birkhoff theorem for finite-height modular lattices has
previously been generalized to complete modular lattices using the theory of
regular coverings. In this paper, we investigate regular coverings in lattices
of filters and lattices of ideals, and the regularization strategy--embedding
the lattice into its lattice of filters or lattice of ideals, thereby possibly
converting a covering which is not regular into a covering which is regular.
One application of the theory is a generalization of the notion of chief
factors, and of the Jordan-Holder Theorem, to cases where the modular lattice
in question is of infinite height. Another application is a formalization of
the notion of the steps in the proof of a theorem.

</DOC>
<DOC>
<DOCNO> 150504 </DOCNO>
D1 and D5-Brane Actions in AdS_m x S^n


  The kappa-invariant and supersymmetric actions of D1 and D5-branes in AdS_3 x
S^3 are investigated, as well as the action of a D5-brane in an AdS_5 x S^5
background. The action of a D5-brane lying totally in an AdS_3 x S^3 background
is found. Some progress was made towards finding the action for the D5-brane
free to move in the whole AdS_3 x S^3 x T^4 space, however the supersymmetric
action found here is not kappa-invariant and the reasons the method used did
not find a kappa-invariant solution are discussed.

</DOC>
<DOC>
<DOCNO> 70579 </DOCNO>
Effective Lagrangian for the pseudoscalars interacting with photons in


  We attempt to evaluate the effective Lagrangian for a classical background
field interacting with the vacuum of two quantum fields. The integration of one
of the quantum fields in general leads to a non-local term in the effective
Lagrangian and thus becomes intractable during the integration of the other
quantum field. We show that $\phi F \tilde{K}$ interaction is an exception. We
present the complete calculation for the evaluation of the effective Lagrangian
for a pseudoscalar field interacting with photons in the presence of a
background electromagnetic field. Expression for the probability of the vacuum
breaking down into a pseudoscalar-photon pair is evaluated. We conclude that
the gradient of an electric field beyond a certain threshold can give rise to
pseudoscalar-photon pair production.

</DOC>
<DOC>
<DOCNO> 10376 </DOCNO>
Why do stripes form in doped antiferromagnets and what is their


  Experiments show evidence for stripe formation in the underdoped cuprates.
Here we discuss recent numerical calculations on the t-J model which tell us
about the mechanism responsible for stripe formation and the relationship
between stripes and superconductivity.

</DOC>
<DOC>
<DOCNO> 69115 </DOCNO>
A Dynamical Model for the Resonant Multipoles and the $\Delta$ Structure


  We show that recent experiment data for the ratios $E_{1^+}/M_{1^+}$ and
$S_{1^+}/M_{1^+}$ can be explained in a dynamical model for electromagnetic
production of pions, together with a simple scaling assumption for the bare
$\gamma^* N \Delta$ form factors. Within our model we find that the bare
$\Delta$ is almost spherical and the electric E2 and Coulomb C2 quadrupole
excitations of the physical $\Delta$ are nearly saturated by pion cloud
contribution in $Q^2 \le 4.0 GeV^2$.

</DOC>
<DOC>
<DOCNO> 40083 </DOCNO>
Searches for prompt light gravitino signatures in e+e- Collisions at


  Searches for final states expected in models with light gravitinos have been
performed, including experimental topologies with multi-leptons with missing
energy, leptons and photons with missing energy, and jets and photons with
missing energy. No excess over the expectations from the Standard Model has
been observed. Limits are placed on production cross-sections in the different
experimental topologies. Additionally, combining with searches for the
anomalous production of lepton and photon pairs with missing energy, results
are interpreted in the context of minimal models of gauge mediated SUSY
breaking. Exclusion limits are established at the 95% confidence level on the
supersymmetric particle masses; m-slepton > 83 GeV and m-neutralino > 85 GeV
for tan(beta)=2, m-stau > 69 GeV, m-selectron,-smu > 88 GeV and m-neutralino >
76 GeV for tan(beta)=20.

</DOC>
<DOC>
<DOCNO> 119074 </DOCNO>
Age and metallicity for six LMC clusters and their surrounding field


  We investigate, on the basis of CCD Stroemgren photometry, the ages and
metallicities of six LMC clusters together with their surrounding field
population. The clusters and metallicities are: NGC1651 (in the range
[Fe/H]=-0.65 dex to -0.41 dex), NGC1711 (-0.57+/-0.17 dex), NGC 1806
(-0.71+/-0.23 dex), NGC2031 (-0.52+/-0.21 dex) and NGC2136/37 (-0.55+/-0.23
dex) and NGC2257 (-1.63+/-0.21 dex). In the cluster surroundings, we found
about 650 field stars that were suitable to be used for a determination of an
age-metallicity relation (AMR). Our method is to estimate ages for individual
stars on the basis of Stroemgren isochrones with individually measured
metallicities. With this method we are able to sample the AMR of the field
population up to 8 Gyr. Our metallicity data are incompatible with models
predicting many metal-poor stars (G-dwarf problem). The metallicity of the
field population increased by a factor of six, starting around 2 Gyr ago. The
proposed AMR is consistent with the AMR of the LMC cluster system (including
ESO 121 SC03 and three clusters with an age of 4 Gyr).

</DOC>
<DOC>
<DOCNO> 151134 </DOCNO>
D-brane annihilation, renormalization-group flow and non-linear


  In this note $D9$- and anti-$D9$-brane annihilation in type I string theory
is probed by a $D1$-brane. We consider the covariant Green-Schwarz or twistor
formulation of the probe theory. We expect the theory to be $\kappa$-invariant
after the annihilation is completed. Conditions of the $\kappa$-invariance of
the theory impose constraints on the background tachyon field. Solutions to the
constraints define tachyon values which correspond to type I $D5$-branes as
remnants of the annihilation. As a byproduct we get a theory which lies in the
same universality class as the non-linear $\sigma$-model for the
Atiyah-Drinfeld-Hitchin-Manin construction.

</DOC>
<DOC>
<DOCNO> 8745 </DOCNO>
Models of fragmentation with power law log-normal distributions


  Two models of binary fragmentation are introduced in which a time dependent
transition size produces two regions of fragment sizes above and below the
transition size. In the models we consider a fixed rate of fragmentation for
the largest fragment and two different rates of fragmentation for the two
regions of sizes above and below the transition size. The models are solved
exactly in the long time limit to reveal stable time-invariant solutions for
the fragment size distributions. A rate of fragmentation proportional to the
inverse of fragment size in the smaller size region produces a power law
distribution in that region. A rate of fragmentation combined of two terms, one
proportional to the inverse of the fragment size and the other proportional to
a logarithmic function of the fragment size, in the larger size region produces
a log-normal distribution in that region. Special cases of the models with no
fragmentation for the smaller fragments are also considered. The similarities
between the stable distributions in our models and power law log-normal
distributions from experimental work on shock fragmentation of long thin glass
rods and rupture of mercury droplets are investigated.

</DOC>
<DOC>
<DOCNO> 11138 </DOCNO>
Effects of field modulation on Aharonov-Bohm cages in a two-dimensional


  We study the effects of field modulation on the energy spectrum of an
electron in a two-dimensional bipartite periodic lattice subject to a magnetic
field. Dependence of the energy spectrum on both the period and the strength of
field modulation is discussed in detail. Our main finding is that introducing
field modulation drastically changes the energy spectrum and the localization
properties of the system appearing in the absence of field modulation; the
degeneracies induced by a uniform magnetic field are broken and the resultant
energy spectrum shows a dispersive band structure, indicating that most of
Aharonov-Bohm cages become unbounded. The effects of field modulation on the
superconducting transition temperature and the critical current in a wire
network with the same geometry are also discussed.

</DOC>
<DOC>
<DOCNO> 116982 </DOCNO>
Analysis and Simulation on the Enhancement of the CSR Effects


  Recent measurements of the coherent synchrotron radiation (CSR) effects
indicated that the observed beam emittance growth and energy modulation are
often bigger than previous predictions based on Gaussian longitudinal charge
distributions. In this paper, by performing a model study, we show both
analytically and numerically that when the longitudinal bunch charge
distribution involves concentration of charges in a small fraction of the bunch
length, enhancement of the CSR self-interaction beyond the Gaussian prediction
may occur. The level of this enhancement is sensitive to the level of the local
charge concentration.

</DOC>
<DOC>
<DOCNO> 11088 </DOCNO>
Levy flights from a continuous-time process


  The Levy-flight dynamics can stem from simple random walks in a system whose
operational time (number of steps n) typically grows superlinearly with
physical time t. Thus, this processes is a kind of continuous-time random walks
(CTRW), dual to usual Scher-Montroll model, in which $n$ grows sublinearly with
t. The models in which Levy-flights emerge due to a temporal subordination let
easily discuss the response of a random walker to a weak outer force, which is
shown to be nonlinear. On the other hand, the relaxation of en ensemble of such
walkers in a harmonic potential follows a simple exponential pattern and leads
to a normal Boltzmann distribution. The mixed models, describing normal CTRW in
superlinear operational time and Levy-flights under the operational time of
subdiffusive CTRW lead to paradoxical diffusive behavior, similar to the one
found in transport on polymer chains. The relaxation to the Boltzmann
distribution in such models is slow and asymptotically follows a power-law.

</DOC>
<DOC>
<DOCNO> 117787 </DOCNO>
The role of Star Formation in the evolution of spiral galaxies


  Spiral galaxies offer a unique opportunity to study the role of star
formation in galaxy evolution and to test various theoretical star formation
schemes. I review some recent relevant work on the evolution of spiral
galaxies. Detailed models are used for the chemical and spectrophotometric
evolution, with metallicity dependent stellar yields, tracks and spectra. The
models are ``calibrated'' on the Milky Way disk and generalised to other
spirals with some simple scaling relations, obtained in the framework of Cold
Dark Matter models for galaxy formation. The results compare favourably to the
main observables of present day spirals, provided a crucial assumption is made:
massive disks form their stars earlier than low mass ones. It is not clear
whether this picture is compatible with currently popular hierarchical models
of galaxy evolution. The resulting abundance gradients are found to be
anticorrelated to the disk scalelength, support radially dependent star
formation efficiencies and point to a kind of ``homologuous evolution'' for
spirals.

</DOC>
<DOC>
<DOCNO> 102636 </DOCNO>
An introduction to o-minimal structures


  The first papers on o-minimal structures appeared in the mid 1980s, since
then the subject has grown into a wide ranging generalisation of semialgebraic,
subanalytic and subpfaffian geometry. In these notes we try to show that this
is in fact the case by presenting several examples of o-minimal structures and
by listing some geometric properties of sets and maps definable in o-minimal
structures. We omit here any reference to the pure model theory of o-minimal
structures and to the theory of groups and rings definable in o-minimal
structures.

</DOC>
<DOC>
<DOCNO> 120460 </DOCNO>
MID-IR Surveys - The Next Generations


  Using new cosmological models for galaxy evolution, predictions for the next
generation of deep mid-IR surveys are presented for both the ASTRO-F space
telescope (due for launch 2003) and the proposed HII/L2 mission (2010).
Although ASTRO-F will be able to detect between 20,000-40,000 sources in the
mid-IR, deep surveys will be severely constrained by confusion due to faint
sources (due to the relatively small aperture of all IR space telescopes to
date). However, HII/L2 with its larger 3.5m mirror will be able to observe to
fluxes 10-100 times deeper below the present confusion limits.

</DOC>
<DOC>
<DOCNO> 116530 </DOCNO>
A transferable nonorthogonal tight-binding model of germanium:


  We have developed a transferable nonorthogonal tight-binding total energy
model for germanium and use it to study small clusters. The cohesive energy,
bulk modulus, elastic constants of bulk germanium can be described by this
model to considerably good extent. The calculated bulk phase diagram for
germanium agrees well with LDA results. The geometries and binding energies
found for small Ge$_n$ clusters with $n=3-10$ are very close to previous {\em
ab initio} calculations and experiments. All these results suggest that this
model can be further applied to the simulation of germanium cluster of larger
size or with longer time scale, for which {\em ab initio} methods is much more
computational expensive.

</DOC>
<DOC>
<DOCNO> 151881 </DOCNO>
The scaling supersymmetric Yang-Lee model with boundary


  We define the scaling supersymmetric Yang-Lee model with boundary as the
(1,3) perturbation of the superconformal minimal model SM(2/8) (or
equivalently, the (1,5) perturbation of the conformal minimal model M(3/8))
with a certain conformal boundary condition. We propose the corresponding
boundary S matrix, which is not diagonal for general values of the boundary
parameter. We argue that the model has an integral of motion corresponding to
an unbroken supersymmetry, and that the proposed S matrix commutes with a
similar quantity. We also show by means of a boundary TBA analysis that the
proposed boundary S matrix is consistent with massless flow away from the
ultraviolet conformal boundary condition.

</DOC>
<DOC>
<DOCNO> 150472 </DOCNO>
N=0 Supersymmetry and the Non-Relativistic Monopole


  We study some of the algebraic properties of the non-relativistic monopole.
We find that we can construct theories that possess an exotic conserved
fermionic charge that squares to the Casimir of the rotation group, yet do not
possess an ordinary supersymmetry. This is in contrast to previous known
examples with such exotic fermionic charges. We proceed to show that the
presence of the exotic fermionic charge in the non-supersymmetric theory can
nonetheless be understood using supersymmetric techniques, providing yet
another example of the usefulness of supersymmetry in understanding
non-supersymmetric theories.

</DOC>
<DOC>
<DOCNO> 117706 </DOCNO>
Radio Properties of z>4 Optically-Selected Quasars


  We report on two programs to address differential evolution between the
radio-loud and radio-quiet quasar populations at high (z>4) redshift. Both
programs entail studying the radio properties of optically-selected quasars.
First, we have observed 32 optically-selected, high-redshift (z>4) quasars with
the VLA at 6 cm (5 GHz). These sources comprise a statistically complete and
well-understood sample. We detect four quasars above our 3-sigma limit of ~0.15
mJy, which is sufficiently sensitive to detect all radio-loud quasars at the
probed redshift range. Second, we have correlated 134 z>4 quasars, comprising
all such sources that we are aware of as of mid-1999, with FIRST and NVSS.
These two recent 1.4 GHz VLA sky surveys reach 3-sigma limits of approximately
0.6 mJy and 1.4 mJy respectively. We identify a total of 15 z>4 quasars, of
which six were not previously known to be radio-loud. The depth of these
surveys does not reach the radio-loud/radio-quiet demarcation luminosity
density (L(1.4 GHz) = 10^32.5 h(50)^(-2) ergs/s/Hz) at the redshift range
considered; this correlation therefore only provides a lower limit to the
radio-loud fraction of quasars at high-redshift. The two programs together
identify eight new radio-loud quasars at z>4, a significant increase over the
seven currently in the published literature. We find no evidence for radio-loud
fraction depending on optical luminosity for -25 > M_B > -28 at z~2, or for
-26>M_B>-28 at z>4. Our results also show no evolution in the radio-loud
fraction between z~2 and z>4 (-26>M_B>-28).

</DOC>
<DOC>
<DOCNO> 13107 </DOCNO>
Exact density profiles for fully asymmetric exclusion process with


  Exact density profiles in the steady state of the one-dimensional fully
asymmetric simple exclusion process on semi-infinite chains are obtained in the
case of forward-ordered sequential dynamics by taking the thermodynamic limit
in our recent exact results for a finite chain with open boundaries. The
corresponding results for sublattice parallel dynamics follow from the
relationship obtained by Rajewsky and Schreckenberg [Physica A 245, 139 (1997)]
and for parallel dynamics from the mapping found by Evans, Rajewsky and Speer
[J. Stat. Phys. 95, 45 (1999)]. By comparing the asymptotic results appropriate
for parallel update with those published in the latter paper, we correct some
technical errors in the final results given there.

</DOC>
<DOC>
<DOCNO> 39732 </DOCNO>
The Cleo III Upgrade


  The CLEO detector at the Cornell Electron Storage Ring (CESR) is completing a
major upgrade that significantly extends its physics reach in the study of
heavy quarks and leptons. The major elements of this detector upgrade are the
installation of a ``fast'' ring imaging Cherenkov detector, a new central drift
chamber and a new barrel-style silicon strip vertex detector. Trigger and data
acquisition systems are also upgraded. We summarize the status of these
detector subsystems as well as the parallel CESR upgrade.

</DOC>
<DOC>
<DOCNO> 100580 </DOCNO>
Cyclic operads and algebra of chord diagrams


  We prove that the algebra $\cal{A}$ of chord diagrams, the dual to the
associated graded algebra of Vassiliev knot invariants, is isomorphic to the
universal enveloping algebra of a Casimir Lie algebra in a certain tensor
category (the PROP for Casimir Lie algebras). This puts on a firm ground a
known statement that the algebra $\cal{A}$ ``looks and behaves like a universal
enveloping algebra''. An immediate corollary of our result is the conjecture of
Bar-Natan, Garoufalidis, Rozansky, and Thurston on the Kirillov-Duflo
isomorphism for algebras of chord diagrams.
  Our main tool is a general construction of a functor from the category
$\mathtt{CycOp}$ of cyclic operads to the category $\mathtt{ModOp}$ of modular
operads which is left adjoint to the ``tree part'' functor $\mathtt{ModOp} \to
\mathtt{CycOp}$. The algebra of chord diagrams arises when this construction is
applied to the operad for Lie algebras. Another example of this construction is
Kontsevich's graph complex that corresponds to the operad for homotopy Lie
algebras.

</DOC>
<DOC>
<DOCNO> 150726 </DOCNO>
On the Effective N=1 Supergravity of M-Theory


  In the low-energy limit, M-theory compactified on S1/Z2 is formulated in
terms of Bianchi identities with sources localized at orbifold singularities
and anomaly-cancelling counterterms to the Wilson effective Lagrangian.
Compactifying to four dimensions on a Calabi-Yau space leads to N=1 local
supersymmetry. We derive a formulation of the effective supergravity which
explicitly relates four-dimensional supergravity multiplets and field equations
with these fundamental M-theory aspects. This formulation proves convenient for
the introduction in the effective supergravity of non-perturbative M-theory
contributions. It also applies to the universal sector of generic
compactifications with N=1 supersymmetry.

</DOC>
<DOC>
<DOCNO> 11903 </DOCNO>
Effects of interladder couplings in the trellis lattice


  Strongly correlated models on coupled ladders in the presence of frustration,
in particular the trellis lattice, are studied by numerical techniques. For the
undoped case, the possibility of incommensurate peaks in the magnetic structure
factor at low temperatures is suggested. In the doped case, our main conclusion
for the trellis lattice is that by increasing the interladder coupling, the
balance between the magnetic energy in the ladders and the kinetic energy in
the zig-zag chains is altered leading eventually to the destruction of the hole
pairs initially formed and localized in the ladders.

</DOC>
<DOC>
<DOCNO> 99740 </DOCNO>
Combinatorial Intersection Cohomology for Fans


  We continue the approach toward a purely combinatorial "virtual" intersection
cohomology for possibly non-rational fans, based on our investigation of
equivariant intersection cohomology for toric varieties (see math.AG/9904159).
Fundamental objects of study are "minimal extension sheaves" on "fan spaces".
These are flabby sheaves of graded modules over a sheaf of polynomial rings,
satisfying three relatively simple axioms that characterize the properties of
the equivariant intersection cohomology sheaf on a toric variety, endowed with
the finite topology given by open invariant subsets. These sheaves are models
for the "pure" objects of a "perverse category"; a "Decomposition Theorem" is
shown to hold. -- Formalizing those fans that define "equivariantly formal"
toric varieties (where equivariant and non-equivariant intersection cohomology
determine each other by Kunneth type formulae), we study "quasi-convex" fans
(including fans with convex or with "co-convex" support). For these, there is a
meaningful "virtual intersection cohomology". We characterize quasi-convex fans
by a topological condition on the support of their boundary fan and prove a
generalization of Stanley's "Local-Global" formula realizing the intersection
Poincare polynomial of a complete toric variety in terms of local data. Virtual
intersection cohomology of quasi-convex fans is shown to satify Poincare
duality. To describe the local data in terms of virtual intersection cohomology
of lower-dimensional complete polytopal fans, one needs a "Hard Lefschetz" type
theorem. It requires a vanishing condition that is known to hold for rational
cones, but yet remains to be proven in the general case.

</DOC>
<DOC>
<DOCNO> 99897 </DOCNO>
Indefinite theta series of signature (1,1) from the point of view of


  We apply the homological mirror symmetry for elliptic curves to the study of
indefinite theta series. We prove that every such series corresponding to a
quadratic form of signature (1,1) can be expressed in terms of theta series
associated with split quadratic forms and the usual theta series. We also show
that indefinite theta series corresponding to univalued Massey products between
line bundles on elliptic curve are modular.

</DOC>
<DOC>
<DOCNO> 68113 </DOCNO>
Time invariance violation in photon-atom and photon-molecule


  A direct experimental proof of very strong T-invariance violation in
interactions of the photons with atoms and molecules exists in the molecular
physics.

</DOC>
<DOC>
<DOCNO> 121364 </DOCNO>
Magnetic Fields are not ignorable in the dynamics of disks


  Magnetic fields are considered to be dominant when
$\epsilon_{B}\geq\epsilon_{K}$, being $\epsilon_{B}=B^{2}/8\pi$ the magnetic
energy density and $\epsilon_{K}=1/2 \rho\theta^{2}$ the rotation energy
density, for a conventional moderate B= 1 $\mu$G. They are considered to be
negligible when $\epsilon_{B}<\epsilon_{K}$ for $B\sim 10 \mu$G. With no
assumption and no theoretical calculation, we show that magnetic fields cannot
be ignored in the outer parts of a galaxy like the Milky Way and in the whole
disk of a dwarf galaxy.

</DOC>
<DOC>
<DOCNO> 84431 </DOCNO>
Adaptive filtering techniques for gravitational wave interferometric


  It is known by the experience gained from the gravitational wave detector
proto-types that the interferometric output signal will be corrupted by a
significant amount of non-Gaussian noise, large part of it being essentially
composed of long-term sinusoids with slowly varying envelope (such as violin
resonances in the suspensions, or main power harmonics) and short-term ringdown
noise (which may emanate from servo control systems, electronics in a
non-linear state, etc.). Since non-Gaussian noise components make the detection
and estimation of the gravitational wave signature more difficult, a denoising
algorithm based on adaptive filtering techniques (LMS methods) is proposed to
separate and extract them from the stationary and Gaussian background noise.
The strength of the method is that it does not require any precise model on the
observed data: the signals are distinguished on the basis of their
autocorrelation time. We believe that the robustness and simplicity of this
method make it useful for data preparation and for the understanding of the
first interferometric data. We present the detailed structure of the algorithm
and its application to both simulated data and real data from the LIGO 40meter
proto-type.

</DOC>
<DOC>
<DOCNO> 11033 </DOCNO>
Electron Cotunneling in a Semiconductor Quantum Dot


  We report transport measurements on a semiconductor quantum dot with a small
number of confined electrons. In the Coulomb blockade regime, conduction is
dominated by cotunneling processes. These can be either elastic or inelastic,
depending on whether they leave the dot in its ground state or drive it into an
excited state, respectively. We are able to discriminate between these two
contributions and show that inelastic events can occur only if the applied bias
exceeds the lowest excitation energy. Implications to energy-level spectroscopy
are discussed.

</DOC>
<DOC>
<DOCNO> 151521 </DOCNO>
Triality of Four Dimensional Strings and Networks


  We apply the string-triality\cite{duffetal} to argue the existence of the
string-networks of solitonic T and U-strings in the heterotic theory on T^6, S
and T-strings in IIB on K3 x T^2 and, S and U-strings in IIA on K3 x T^2. We
then show the existence of the above heterotic string networks by analyzing the
supersymmetry property of the supergravity solutions. The consistency of these
networks with supersymmetry in the case of IIA and IIB theories is also argued.
Our results therefore give further evidence in favor of the string-triality in
four dimensions.

</DOC>
<DOC>
<DOCNO> 118877 </DOCNO>
The saturation of disk heating in the solar neighborhood and evidence


  We re-examine the age-velocity dispersion relation in the solar neighborhood
using improved stellar age estimates that are based on Hipparcos parallaxes and
recent stellar evolution calculations. The resulting relation shows that the
Milky Way stellar disk was relatively quiescent, suffering little heating or
dispersion increase between 3 and 9 Gyrs. However, at an age of 9 Gyrs there is
an abrupt increase in the stellar velocity dispersions. To explain the abrupt
increase (by almost a factor of 2) in dispersions we propose that the Milky Way
suffered a minor merger 9 Gyrs ago that created the thick disk. The quiescent
phase is consistent with inefficient heating caused by scattering from tightly
wound transient spiral structure. It is possible that many galaxy disks have
radial velocity dispersions at the point where heating from spiral structure
becomes inefficient. Surface brightness profiles and dispersion measurements
can be used to predict spiral arm winding numbers at this saturation point. A
comparison between the observed and predicted winding numbers could test this
hypothesis and also search for evidence of merger induced disk heating in
nearby galaxies.

</DOC>
<DOC>
<DOCNO> 123192 </DOCNO>
Spin and magnetism in old neutron stars


  The thermal, spin and magnetic evolution of neutron stars in the old low mass
binaries is first explored. Recycled to very short periods via accretion
torques, the neutron stars lose their magnetism progressively. If accretion
proceeds undisturbed for 100 Myrs these stars can rotate close to break up with
periods far below the minimum observed of 1.558 ms. We investigate their
histories using population synthesis models to show that a tail should exist in
the period distribution below 1.558 ms. The search of these ultrafastly
spinning neutron stars as pulsars can help discriminating among the various
equations of state for nuclear matter, and can shed light into the physics of
binary evolution.
  The evolution of isolated neutron stars in the Galaxy is explored beyond the
pulsar phase. Moving through the tenuous interstellar medium, these old
solitary neutron stars lose their rotational energy. Whether also their
magnetism fades is still a mystery. A population synthesis model has revealed
that only a tiny fraction of them is able to accrete from the interstellar
medium, shining in the X-rays. There is the hope that these solitary stars will
eventually appear as faint sources in the Chandra sky survey. This might give
insight on the long term evolution of the magnetic field in isolated objects.

</DOC>
<DOC>
<DOCNO> 100328 </DOCNO>
A functional expression for the curvature of hyper-dimensional


  Analogously to the concept of a curvature of curve and surface, in the
differential geometry, in the main part of this paper the concept of the
curvature of the hyper-dimensional vector spaces of Riemannian metric is
generally defined. The defined concept of the curvature of Riemannian spaces of
higher dimensions M: M>1, in the further text of the paper, is functional
related to the fundamental parameters of an internal geometry of space, more
exactly, to components of Riemann-Christoffel's tensor of curvature. At the
end, analogously to the concept of lines of curvature in the differential
geometry, the concept of sub-spaces of curvature of Riemannian
hyper-dimensional vector spaces is also generally defined.

</DOC>
<DOC>
<DOCNO> 101488 </DOCNO>
The transcendental part of the regulator map for K_1 on a mirror family


  We compute the transcendental part of the normal function corresponding to
the Deligne class of a cycle in K_1 of a mirror family of quartic K3 surfaces.
The resulting multivalued function does not satisfy the hypergeometric
differential equation of the periods and we conclude that the cycle is
indecomposable for most points in the mirror family. The occurring inhomogenous
Picard-Fuchs equation are related to Painlev\'e VI type differential equations.

</DOC>
<DOC>
<DOCNO> 9234 </DOCNO>
Growth enhanced surface diffusion and elastic instability on amorphous


  A continuum model for growth of solids is developed, considering adatom
deposition, surface diffusion, and configuration dependent incorporation rate.
For amorphous solids it is related to surface energy densities. The high adatom
density leads to growth enhanced dynamics of (a) Mullins' classical equation
[J. Appl. Phys. {\bf 28}, 333 (1957)] without, and (b) of the
Asaro-Tiller-Grinfeld-Srolovitz instability with lateral stress in the growing
film. The latter mechanism is attributed to morphologies found in recent
experiments.

</DOC>
<DOC>
<DOCNO> 150469 </DOCNO>
Domain Walls and Massive Gauged Supergravity Potentials


  We point out that massive gauged supergravity potentials, for example those
arising due to the massive breathing mode of sphere reductions in M-theory or
string theory, allow for supersymmetric (static) domain wall solutions which
are a hybrid of a Randall-Sundrum domain wall on one side, and a dilatonic
domain wall with a run-away dilaton on the other side. On the anti-de Sitter
(AdS) side, these walls have a repulsive gravity with an asymptotic region
corresponding to the Cauchy horizon, while on the other side the runaway
dilaton approaches the weak coupling regime and a non-singular attractive
gravity, with the asymptotic region corresponding to the boundary of spacetime.
We contrast these results with the situation for gauged supergravity potentials
for massless scalar modes, whose supersymmetric AdS extrema are generically
maxima, and there the asymptotic regime transverse to the wall corresponds to
the boundary of the AdS spacetime. We also comment on the possibility that the
massive breathing mode may, in the case of fundamental domain-wall sources,
stabilize such walls via a Goldberger-Wise mechanism.

</DOC>
<DOC>
<DOCNO> 100816 </DOCNO>
Virtual Fundamental Classes of Zero Loci


  Let V be a convex vector bundle over a smooth projective manifold X, and let
Y be the subset of X which is the zero locus of a regular section of V. This
mostly expository paper discusses a conjecture which relates the virtual
fundamental classes of X and Y. Using an argument due to Gathmann, we prove a
special case of the conjecture. The paper concludes with a discussion of how
our conjecture relates to the mirror theorems in the literature.

</DOC>
<DOC>
<DOCNO> 8009 </DOCNO>
Stability of trions in strongly spin-polarized two-dimensional electron


  Low-temperature magneto-photoluminescence studies of negatively charged
excitons (X- trions) are reported for n-type modulation-doped ZnSe/Zn(Cd,Mn)Se
quantum wells over a wide range of Fermi energy and spin-splitting. The
magnetic composition is chosen such that these magnetic two-dimensional
electron gases (2DEGs) are highly spin-polarized even at low magnetic fields,
throughout the entire range of electron densities studied (5e10 to 6.5e11
cm^-2). This spin polarization has a pronounced effect on the formation and
energy of X-, with the striking result that the trion ionization energy (the
energy separating X- from the neutral exciton) follows the temperature- and
magnetic field-tunable Fermi energy. The large Zeeman energy destabilizes X- at
the nu=1 quantum limit, beyond which a new PL peak appears and persists to 60
Tesla, suggesting the formation of spin-triplet charged excitons.

</DOC>
<DOC>
<DOCNO> 121199 </DOCNO>
Bondi-Hoyle-Lyttleton Accretion Model for Low-luminosity X-ray Sources


  We present a new model for low-luminosity X-ray sources in globular clusters,
with L_x < 10^34 erg/s. The model we propose is that of a single neutron star
accreting from cluster gas that has accumulated as a natural product of stellar
evolution. An analytic luminosity function is derived under the assumption that
the speed distribution of neutron stars in the central region of a cluster is
described by a Maxwellian, and that the density and temperature of the gas are
uniform. Predictions of the model and implications for the gas content of
globular clusters are discussed.

</DOC>
<DOC>
<DOCNO> 122193 </DOCNO>
Estimating jet power in proton blazar models


  We discuss the various contributions to the jet luminosity in proton blazar
models of active galactic nuclei and describe a method of estimating the jet
luminosity from the observed spectral energy distribution (SED) and the fitted
model parameters. We apply this to a synchrotron proton blazar (SPB) model for
Markarian 501.

</DOC>
<DOC>
<DOCNO> 117984 </DOCNO>
The Composition and Distribution of Dust Along the Line of Sight Towards


  We discuss the composition of dust and ice along the line of sight to the
Galactic Center (GC) based on analysis of mid-infrared spectra (2.4-13 micron)
from the Short Wavelength Spectrometer on the Infrared Space Observatory (ISO).
We have analyzed dust absorption features arising in the molecular cloud
material and the diffuse interstellar medium along the lines of sight toward
Sagittarius A* and the Quintuplet sources, GCS3 and GCS4. It is evident from
the depth of the 3.0 micron H2O and the 4.27 micron CO2 ice features that there
is more molecular cloud material along the line of sight toward Sgr A* than
GCS3 and 4. In fact, Sgr A* has a rich infrared ice spectrum with evidence for
the presence of solid CH4, NH3, and possibly HCOOH.
    Hydrocarbon dust in the diffuse interstellar medium along the line of sight
to the GC is characterized by absorption features centered at 3.4, 6.85, and
7.25 micron. Ground-based studies have identified the 3.4 micron feature with
aliphatic hydrocarbons, and ISO has given us the first meaningful observations
of the corresponding modes at longer wavelengths. The integrated strengths of
these three features suggest that hydrogenated amorphous carbon is their
carrier. We attribute an absorption feature centered at 3.28 micron in the GCS3
spectrum to the C-H stretch in aromatic hydrocarbons. This feature is not
detected, and its C-C stretch counterpart appears to be weaker, in the SgrA*
spectrum. One of the key questions which now arises is whether aromatics are a
widespread component of the diffuse interstellar medium, analogous to aliphatic
hydrocarbons.

</DOC>
<DOC>
<DOCNO> 179004 </DOCNO>
Solution of the Dyson equation for nucleons in the superfluid phase


  We investigate the role the interweaving of surface vibrations and nucleon
motion has on Cooper pair formation in spherical superfluid nuclei. A
quantitative calculation of the state-dependent pairing gap requires to go
beyond the quasiparticle approximation, treating in detail the breaking of the
single-particle strength and of the associated poles. This is done solving
self-consistently the Dyson equation, including both a bare nucleon-nucleon
interaction (which for simplicity we choose as a monopole-pairing force of
constant matrix elements g) and an induced interaction arizing from the
exchange of vibrations (calculated microscopically in QRPA) between pairs of
nucleons moving in time reversal states. Both the normal and anomalous density
Green functions are included, thus treating self-energy and pairing processes
on equal footing. We apply the formalism to the superfluid nucleus 120Sn.
Adjusting the value of g so as to reproduce, for levels close to the Fermi
level, the empirical odd-even mass difference (Delta approx 1.4 MeV), it is
found that the pairing gap receives about equal contributions from the
monopole-pairing force and from the induced interaction. [More sentences
continue. See the main body.]

</DOC>
<DOC>
<DOCNO> 122440 </DOCNO>
Adaptive binning of X-ray galaxy cluster images


  We present a simple method for adaptively binning the pixels in an image. The
algorithm groups pixels into bins of size such that the fractional error on the
photon count in a bin is less than or equal to a threshold value, and the size
of the bin is as small as possible. The process is particularly useful for
generating surface brightness and colour maps, with clearly defined error maps,
from images with a large dynamic range of counts, for example X-ray images of
galaxy clusters. We demonstrate the method in application to data from Chandra
ACIS-S and ACIS-I observations of the Perseus cluster of galaxies. We use the
algorithm to create intensity maps, and colour images which show the relative
X-ray intensities in different bands. The colour maps can later be converted,
through spectral models, into maps of physical parameters, such as temperature,
column density, etc. The adaptive binning algorithm is applicable to a wide
range of data, from observations or numerical simulations, and is not limited
to two-dimensional data.

</DOC>
<DOC>
<DOCNO> 7816 </DOCNO>
Non-rigid shell model and novel correlational effects in atomic and


  Direct analytical and numerical calculation show that two-electron atomic
configuration can be unstable with respect to a static or dynamic shift of the
electron shells. This enables to develop a so called non-rigid shell model for
a partial account of the electron correlations within atomic clusters in
solids. In a framework of this model a correlated state of two-electron
molecular configuration is described by a set of symmetrized shell shifts
q^\gamma similarly to the well known shell model developed for a description of
the lattice dynamics. A set of q^\gamma-shifts are found after minimization of
the energy functional. We present a number of the novel unconventional effects
including: i) a correlational mechanism of the local pairing; ii) a
correlational (pseudo) Jahn-Teller effect provided by a joint account of the
electron shell shifts and conventional nuclear displacements; iii) an
appearance of the chiral correlational states. The model allows an introduction
of the pseudo-spin formalism and effective "spin-Hamiltonian" for a description
of the short- and long-range ordering of non-rigid atomic backgrounds in
crystals. Finally, the model can be readily built in the conventional band
schemes.

</DOC>
<DOC>
<DOCNO> 102066 </DOCNO>
Unknotting tunnels and Seifert surfaces


  Let $K$ be a knot with an unknotting tunnel $\gamma$ and suppose that $K$ is
not a 2-bridge knot. There is an invariant $\rho = p/q \in \mathbb{Q}/2
\mathbb{Z}$, $p$ odd, defined for the pair $(K, \gamma)$.
  The invariant $\rho$ has interesting geometric properties: It is often
straightforward to calculate; e. g. for $K$ a torus knot and $\gamma$ an
annulus-spanning arc, $\rho(K, \gamma) = 1$. Although $\rho$ is defined
abstractly, it is naturally revealed when $K \cup \gamma$ is put in thin
position. If $\rho \neq 1$ then there is a minimal genus Seifert surface $F$
for $K$ such that the tunnel $\gamma$ can be slid and isotoped to lie on $F$.
One consequence: if $\rho(K, \gamma) \neq 1$ then $genus(K) > 1$. This confirms
a conjecture of Goda and Teragaito for pairs $(K, \gamma)$ with $\rho(K,
\gamma) \neq 1$.

</DOC>
<DOC>
<DOCNO> 102390 </DOCNO>
Analytic aspects of the Toda system: I. A Moser-Trudinger inequality


  We analyze solutions of the Toda system and establish an optimal
Moser-Trudinger inequality

</DOC>
<DOC>
<DOCNO> 40189 </DOCNO>
Final States in Diffraction at HERA


  Recent experimental results on diffractive high $E_T$ jet production and
diffractive open charm production, obtained by the H1 and ZEUS experiments at
HERA, are presented. Various theoretical models for diffractive hard scattering
are discussed and confronted with the experimental data.

</DOC>
<DOC>
<DOCNO> 121855 </DOCNO>
UBVRI photometry of Southern Sky BL Lacs


  Seventeen southern sky BL Lacs were observed in UBVRI using the CCD Camera on
the 1.0m telescope at the South African Astronomical Observatory (SAAO) in Aug
and Nov 1999. The analyses of all the seventeen sources are now complete, and
are available via anonymous ftp (ftp pukrs1.puk.ac.za/pub/Blazars). A few
examples of our results are however given in this paper. Whereas PKS 2005-489
and PKS 2155-304 apear to have been in a high state, PKS 0048-097 and PKS
0521-365 showed evidence of variability on a time-scale of a few days, with the
amplitude of variability increasing towards short wavelengths. This is
consistent with observations of gamma-ray BL Lacs, which show similar behaviour
in optical and X-rays.

</DOC>
<DOC>
<DOCNO> 117665 </DOCNO>
On the Viewing Angle Dependence of Blazar Variability


  Internal shocks propagating through an ambient radiation field, are subject
to a radiative drag that, under certain conditions, can significantly affect
their dynamics and, consequently, the evolution of the beaming cone of emission
produced behind the shocks. The resultant change of the Doppler factor combined
with opacity effects leads to a strong dependence of the variability pattern
produced by such systems, specifically, the shape of the light curves and the
characteristics of correlated emission, on viewing angle. One implication is
that objects oriented at relatively large viewing angles to the observer should
exhibit a higher level of activity at high synchrotron frequencies (above the
self-absorption frequency) and at gamma-ray energies below the threshold energy
to pair production, than at lower (radio/millimeter) frequencies.

</DOC>
<DOC>
<DOCNO> 122121 </DOCNO>
XMM-Newton Optical Monitor observations of LMC X-3


  We study the optical counterpart of the black-hole X-ray binary LMC X-3, by
using XMM-Newton/OM observations carried out during a low-hard X-ray state. We
derive a better constraint for the temperature, mass and radius of the
companion star, and we show that the star is likely to be a ~ B5 subgiant
filling its Roche lobe. Taking into account the effect of X-ray irradiation, we
suggest a value f_M = (1.5 +/- 0.3) M_sun for the mass function in this system,
lower than previously thought; we provide a more accurate lower limit to the
mass of the compact object.

</DOC>
<DOC>
<DOCNO> 9925 </DOCNO>
Current driven switching of magnetic layers


  The switching of magnetic layers is studied under the action of a spin
current in a ferromagnetic metal/non-magnetic metal/ferromagnetic metal spin
valve. We find that the main contribution to the switching comes from the
non-equilibrium exchange interaction between the ferromagnetic layers. This
interaction defines the magnetic configuration of the layers with minimum
energy and establishes the threshold for a critical switching current.
Depending on the direction of the critical current, the interaction changes
sign and a given magnetic configuration becomes unstable. To model the time
dependence of the switching process, we derive a set of coupled Landau-Lifshitz
equations for the ferromagnetic layers. Higher order terms in the
non-equilibrium exchange coupling allow the system to evolve to its
steady-state configuration.

</DOC>
<DOC>
<DOCNO> 11876 </DOCNO>
Anomalous aging phenomena caused by drift velocities


  We demonstrate via several examples that a uniform drift velocity gives rise
to anomalous aging, characterized by a specific form for the two-time
correlation functions, in a variety of statistical-mechanical systems far from
equilibrium. Our first example concerns the oscillatory phase observed recently
in a model of competitive learning. Further examples, where the proposed theory
is exact, include the voter model and the Ohta-Jasnow-Kawasaki theory for
domain growth in any dimension, and a theory for the smoothing of sandpile
surfaces.

</DOC>
<DOC>
<DOCNO> 120861 </DOCNO>
Deep Halpha imagery of the Eridanus shells


  A deep \ha image of interlocking filamentary arcs of nebulosity has been
obtained with a wide-field ($\approx$ 30\degree diameter) narrow-band filter
camera combined with a CCD as a detector. The resultant mosaic of images,
extending to a galactic latitude of 65$^{o}$, has been corrected for field
distortions and had galactic coordinates superimposed on it to permit accurate
correlations with the most recent H{\sc i} (21 cm), X-ray (0.75 kev) and FIR
(IRAS 100 $\mu$m) maps.
  Furthermore, an upper limit of 0.13 arcsec/yr to the expansion proper motion
of the primary 25\degree long nebulous arc has been obtained by comparing a
recent \ha image obtained with the San Pedro Martir telescope of its
filamentary edge with that on a POSS E plate obtained in 1951.
  It is concluded that these filamentary arcs are the superimposed images of
separate shells (driven by supernova explosions and/or stellar winds) rather
than the edges of a single `superbubble' stretching from Barnard's Arc (and the
Orion Nebula) to these high galactic latitudes. The proper motion measurement
argues against the primary \ha emitting arc being associated with the giant
radio loop (Loop 2) except in extraordinary circumstances.

</DOC>
<DOC>
<DOCNO> 122461 </DOCNO>
Peculiarities of anisotropy and polarization as an indicator of noises


  We discuss some new problems of the modern cosmology which arose after the
BOOMERANG and MAXIMA-1 successful missions. Statistics of high peaks of the CMB
anisotropy is analyzed and we discuss possible inner structure of such peaks in
the observational data of future MAP and PLANCK missions. We have investigated
geometrical and statistical properties of the CMB polarization around such high
isolated peaks of anisotropy in the presence of a polarized pixel noise and
point sources. The structure of polarization fields in the vicinity of singular
points with zero polarization is very sensitive to the level of pixel noises
and point sources in the CMB maps.

</DOC>
<DOC>
<DOCNO> 7901 </DOCNO>
Asymmetric exclusion process with next-nearest-neighbor interaction:


  We study the steady-state behavior of a driven non-equilibrium lattice gas of
hard-core particles with next-nearest-neighbor interaction. We calculate the
exact stationary distribution of the periodic system and for a particular line
in the phase diagram of the system with open boundaries where particles can
enter and leave the system. For repulsive interactions the dynamics can be
interpreted as a two-speed model for traffic flow. The exact stationary
distribution of the periodic continuous-time system turns out to coincide with
that of the asymmetric exclusion process (ASEP) with discrete-time parallel
update. However, unlike in the (single-speed) ASEP, the exact flow diagram for
the two-speed model resembles in some important features the flow diagram of
real traffic. The stationary phase diagram of the open system obtained from
Monte Carlo simulations can be understood in terms of a shock moving through
the system and an overfeeding effect at the boundaries, thus confirming
theoretical predictions of a recently developed general theory of
boundary-induced phase transitions. In the case of attractive interaction we
observe an unexpected reentrance transition due to boundary effects.

</DOC>
<DOC>
<DOCNO> 118854 </DOCNO>
Cooling neutron stars with localized protons


  We analyze cooling of neutron stars, assuming the presence of localized
protons in the densest region of their cores. Choosing a single threshold
density for proton localization and adjusting neutron star mass, we reproduce
the observational data on effective surface temperatures of Vela and PSR
0656+14, with or without an accreted hydrogen envelope. However, the presence
of a tiny hydrogen envelope is mandatory, in this model, for reproducing the
Geminga data.

</DOC>
<DOC>
<DOCNO> 67716 </DOCNO>
On the Mixing of the Scalar Mesons $f_0(1370)$, $f_0(1500)$ and


  Based on a $3\times3$ mass matrix describing the mixing of the scalar states
$f_0(1370)$, $f_0(1500)$ and $f_0(1710)$, the hadronic decays of the three
states are investigated. Taking into account the two possible assumptions
concerning the mass level order of the bare states
$|N>=|u\bar{u}+d\bar{d}>/\sqrt{2}$, $|S>=|s\bar{s}>$ and $|G>=|gg>$ in the
scalar sector, $M_G > M_S > M_N$ and $M_G > M_N > M_S$, we obtain the
glueball-quarkonia content of the three states by solving the unlinear
equations. Some predictions about the decays of the three states in two cases
are presented, which can provide a stringent consistency check of the two
assumptions.

</DOC>
<DOC>
<DOCNO> 118453 </DOCNO>
The Sunyaev-Zel'dovich Effect in Abell 370


  We present interferometric measurements of the Sunyaev-Zel'dovich (SZ) effect
towards the galaxy cluster Abell 370. These measurements, which directly probe
the pressure of the cluster's gas, show the gas distribution to be strongly
aspherical, as do the x-ray and gravitational lensing observations. We
calculate the cluster's gas mass fraction in two ways. We first compare the gas
mass derived from the SZ measurements to the lensing-derived gravitational mass
near the critical lensing radius. We also calculate the gas mass fraction from
the SZ data by deprojecting the three-dimensional gas density distribution and
deriving the total mass under the assumption that the gas is in hydrostatic
equilibrium (HSE). We test the assumptions in the HSE method by comparing the
total cluster mass implied by the two methods and find that they agree within
the errors of the measurement. We discuss the possible systematic errors in the
gas mass fraction measurement and the constraints it places on the matter
density parameter, OmegaM.

</DOC>
<DOC>
<DOCNO> 116281 </DOCNO>
Capillary-gravity wave transport over spatially random drift


  We derive transport equations for the propagation of water wave action in the
presence of a static, spatially random surface drift. Using the Wigner
distribution $\W(\x,\k,t)$ to represent the envelope of the wave amplitude at
position $\x$ contained in waves with wavevector $\k$, we describe surface wave
transport over static flows consisting of two length scales; one varying
smoothly on the wavelength scale, the other varying on a scale comparable to
the wavelength. The spatially rapidly varying but weak surface flows augment
the characteristic equations with scattering terms that are explicit functions
of the correlations of the random surface currents. These scattering terms
depend parametrically on the magnitudes and directions of the smoothly varying
drift and are shown to give rise to a Doppler coupled scattering mechanism. The
Doppler interaction in the presence of slowly varying drift modifies the
scattering processes and provides a mechanism for coupling long wavelengths
with short wavelengths. Conservation of wave action (CWA), typically derived
for slowly varying drift, is extended to systems with rapidly varying flow. At
yet larger propagation distances, we derive from the transport equations, an
equation for wave energy diffusion. The associated diffusion constant is also
expressed in terms of the surface flow correlations. Our results provide a
formal set of equations to analyse transport of surface wave action, intensity,
energy, and wave scattering as a function of the slowly varying drifts and the
correlation functions of the random, highly oscillatory surface flows.

</DOC>
<DOC>
<DOCNO> 122030 </DOCNO>
Chandra Observation of M84, Radio Lobe Elliptical in Virgo cluster


  We analyzed a deep Chandra observation of M84, a bright elliptical galaxy in
the core of the Virgo cluster. We find that the spatial distribution of the
soft X-ray emission is defined by the radio structure of the galaxy. In
particular we find two low density regions associated with the radio lobes and
surrounded by higher density X-ray filaments. In addition to a central AGN and
a population of galactic sources, we find a diffuse hard source filling the
central 10 kpc region. Since the morphology of the hard source appears round
and is different from that seen in the radio or in soft X-rays, we propose that
it is hot gas heated by the central AGN. Finally, we find that the central
elemental abundance in the X-ray gas is comparable to that measured optically.

</DOC>
<DOC>
<DOCNO> 84216 </DOCNO>
Moduli Spaces for Four- and Five- Dimensional Black Holes


  We propose a universal expression for the moduli metric of a class of four-
and five-dimensional black holes which preserve at least four supersymmetries.
These include the black holes that are associated with various intersecting
branes in ten and eleven dimensions, the electrically charged black holes of
N=2 D=5 and N=2 D=4 supergravities with any number of vector multiplets, and
dyonic black holes of N=2 D=4 supergravity. The moduli metric of electrically
charged N=2 D=4 black holes coupled to any number of vector multiplets is
explicitly computed. We also investigate the superconformal symmetries of the
black hole moduli spaces for small black hole separations.

</DOC>
<DOC>
<DOCNO> 99490 </DOCNO>
Solutions to congruences using sets with the property of Baire


  Hausdorff's paradoxical decomposition of a sphere with countably many points
removed (the main precursor of the Banach-Tarski paradox) actually produced a
partition of this set into three pieces A,B,C such that A is congruent to B
(i.e., there is an isometry of the set which sends A to B), B is congruent to
C, and A is congruent to (B union C). While refining the Banach-Tarski paradox,
R. Robinson characterized the systems of congruences like this which could be
realized by partitions of the sphere with rotations witnessing the congruences.
The purpose of the present paper is to characterize those systems of
congruences which can be satisfied by partitions of the sphere or related
spaces (any complete metric space acted on in a sufficiently free way by a free
group of homeomorphisms) into sets with the property of Baire. Dougherty and
Foreman proved that the Banach-Tarski paradox can be achieved using such sets,
and gave versions of this result using open sets and related results about
partitions of spaces into congruent sets. The same methods are used here. We
also characterize the systems solvable on the sphere using sets with the
property of Baire but allowing all isometries (instead of just rotations).

</DOC>
<DOC>
<DOCNO> 151361 </DOCNO>
Exact BRS Symmetry realized on the Renormalization Group Flow


  Using the average action defined with a continuum analog of the block spin
transformation, we show the presence of gauge symmetry along the Wilsonian
renormalization group flow. As a reflection of the gauge symmetry, the average
action satisfies the quantum master equation(QME). We show that the quantum
part of the master equation is naturally understood once the measure
contribution under the BRS transformation is taken into account. Furthermore an
effective BRS transformation acting on macroscopic fields may be defined from
the QME. The average action is explicitly evaluated in terms of the saddle
point approximation up to one-loop order. It is confirmed that the action
satisfies the QME and the flow equation.

</DOC>
<DOC>
<DOCNO> 14057 </DOCNO>
Ground state energy of metallic ferromagnet in a generalized Hubbard


  In the present work ferromagnetic ordering in the Hubbard model generalized
by taking into account the inter-atomic exchange interaction and correlated
hopping in partially filled narrow band is considered. In the case of weak
electron-electron interaction the ground state energy and condition of
ferromagnetic state realization are found using the Green function technique.
The obtained results indicate the important role of correlated hopping.

</DOC>
<DOC>
<DOCNO> 71568 </DOCNO>
Proton Stability and Superstring Z'


  Recently it was argued that proton lifetime limits impose that the scale of
quantum gravity must be above 10^{16} GeV. By studying the proton stability in
the context of realistic heterotic-string models, I propose that proton
longevity necessitates the existence of an additional U(1)_{Z'} symmetry, which
is of non-GUT origin and remains unbroken down to intermediate, or low,
energies. It is shown that the realistic string models frequently give rise to
U(1) symmetries, which suppress the proton decay mediating operators, with, or
without, the possibility of R-parity violation. By studying the F- and D-flat
directions, I examine whether the required symmetries remain unbroken in the
supersymmetric vacuum and show that in some examples they can, whereas in
others they cannot. The proton decay rate is proportional to the U(1)_{Z'}
symmetry breaking scale. Imposing the proton lifetime limits I estimate the
U(1)_{Z'} breaking scale and show that if substantial R-parity violation is
present the associated Z' is within reach of forthcoming collider experiments

</DOC>
<DOC>
<DOCNO> 9740 </DOCNO>
Macroscopic quantum tunneling and resonances in coupled Bose-Einstein


  We study the macroscopic quantum tunneling, self-trapping phenomena in two
weakly coupled Bose-Einstein condensates with periodically time-varying atomic
scattering length.
  The resonances in the oscillations of the atomic populations are
investigated. We consider oscillations in the cases of macroscopic quantum
tunneling and the self-trapping regimes. The existence of chaotic oscillations
in the relative atomic population due to overlaps between nonlinear resonances
is showed. We derive the whisker-type map for the problem and obtain the
estimate for the critical amplitude of modulations leading to chaos. The
diffusion coefficient for motion in the stochastic layer near separatrix is
calculated. The analysis of the oscillations in the rapidly varying case shows
the possibilty of stabilization of the unstable Pi-mode regime.

</DOC>
<DOC>
<DOCNO> 117759 </DOCNO>
Superwind-Driven Intense H_2 Emission in NGC 6240


  We have performed a long-slit K band spectroscopic observation of the
luminous infrared galaxy NGC 6240. The peak position of the H_2 v=1-0 S(1)
emission in the slit is located ~0.3" - 0.4" north of the southern nucleus. It
is almost the midpoint between the southern nucleus and the peak position of
the ^12CO J=1-0 emission. Based on the line-ratio analyses, we suggest the
excitation mechanism of H_2 is pure thermal at most positions. In the southern
region we find the following three velocity components in the H_2 emission: the
blueshifted shell component (~-250 km s^-1 with respect to V_sys) which is
recognized as a distinct C-shape distortion in the velocity field around the
southern nucleus, the high-velocity blueshifted ``wing'' component (~-1000 km
s^-1 with respect to V_sys), and the component indicating possible line
splitting of ~500 km s^-1. The latter two components are extended to the south
from the southern nucleus. We show that the kinematic properties of these three
components can be reproduced by expanding motion of a shell-like structure
around the southern nucleus. The offset peak position of the H_2 emission can
be understood if we assume that the shell expanding to the north interacts with
the extragalactic molecular gas. At the interface between the shell and the
molecular gas concentration the cloud-crushing mechanism proposed by Cowie et
al. (1981) may work efficiently, and the intense H_2 emission is thus expected
there. All these findings lead us to propose a model that the most H_2 emission
is attributed to the shock excitation driven by the superwind activity of the
southern nucleus.

</DOC>
<DOC>
<DOCNO> 11857 </DOCNO>
Optimal basis set for electronic structure calculations in periodic


  An efficient method for calculating the electronic structure of systems that
need a very fine sampling of the Brillouin zone is presented. The method is
based on the variational optimization of a "single" (i.e. common to all points
in the Brillouin zone) basis set for the expansion of the electronic orbitals.
Considerations from k.p-approximation theory help to understand the efficiency
of the method. The accuracy and the convergence properties of the method as a
function of the optimal basis set size are analysed for a test calculation on a
16-atom Na supercell.

</DOC>
<DOC>
<DOCNO> 121030 </DOCNO>
High redshift radio galaxies: Beacons to biased hierarchical galaxy


  We summarize observations of the properties of powerful radio galaxies and
their environments from z = 0 to 5. These data show that some high redshift
radio galaxies inhabit regions of gas and galaxy over-densities indicative of
proto-cluster environments.

</DOC>
<DOC>
<DOCNO> 169722 </DOCNO>
Unitary transformation approach for the trapped ion dynamics


  We present a way of treating the problem of the interaction of a single
trapped ion with laser beams based on successive aplications of unitary
transformations onto the Hamiltonian. This allows the diagonalization of the
Hamiltonian, by means of recursive relations, without performing the Lamb-Dicke
approximation.

</DOC>
<DOC>
<DOCNO> 8534 </DOCNO>
Liouvillian Approach to the Integer Quantum Hall Effect Transition


  We present a novel approach to the localization-delocalization transition in
the integer quantum Hall effect. The Hamiltonian projected onto the lowest
Landau level can be written in terms of the projected density operators alone.
This and the closed set of commutation relations between the projected
densities leads to simple equations for the time evolution of the density
operators. These equations can be used to map the problem of calculating the
disorder averaged and energetically unconstrained density-density correlation
function to the problem of calculating the one-particle density of states of a
dynamical system with a novel action. At the self-consistent mean-field level,
this approach yields normal diffusion and a finite longitudinal conductivity.
While we have not been able to go beyond the saddle point approximation
analytically, we show numerically that the critical localization exponent can
be extracted from the energetically integrated correlation function yielding
$\nu=2.33 \pm 0.05$ in excellent agreement with previous finite-size scaling
studies.

</DOC>
<DOC>
<DOCNO> 11535 </DOCNO>
Local structure study of In_xGa_(1-x)As semiconductor alloys using High


  Nearest and higher neighbor distances as well as bond length distributions
(static and thermal) of the In_xGa_(1-x)As (0<x<1) semiconductor alloys have
been obtained from high real-space resolution atomic pair distribution
functions (PDFs). Using this structural information, we modeled the local
atomic displacements in In_xGa_(1-x)As alloys. From a supercell model based on
the Kirkwood potential, we obtained 3-D As and (In,Ga) ensemble averaged
probability distributions. This clearly shows that As atom displacements are
highly directional and can be represented as a combination of <100> and <111>
displacements. Examination of the Kirkwood model indicates that the standard
deviation (sigma) of the static disorder on the (In,Ga) sublattice is around
60% of the value on the As sublattice and the (In,Ga) atomic displacements are
much more isotropic than those on the As sublattice. The single crystal diffuse
scattering calculated from the Kirkwood model shows that atomic displacements
are most strongly correlated along <110> directions.

</DOC>
<DOC>
<DOCNO> 150829 </DOCNO>
Level Four Approximation to the Tachyon Potential in Superstring Field


  We compute the tachyon potential to level 4 in NS superstring field theory.
We obtain 89% of the conjectured vacuum energy.

</DOC>
<DOC>
<DOCNO> 121587 </DOCNO>
High-Redshift Galaxies: The Far-Infrared and Sub-Millimeter View


  Observations at long wavelengths, in the wide interval from a few to 1000
micron, are essential to study diffuse media in galaxies, including all kinds
of atomic, ionic and molecular gases and dust grains. Hence they are
particularly suited to investigate the early phases in galaxy evolution, when a
very rich ISM is present in the forming systems.
  During the last few years a variety of observational campaigns in the
far-IR/sub-mm, exploiting both ground-based and space instrumentation, have
started to provide results of relevant cosmological impact. Most crucial among
these have been the discovery of an intense diffuse background in the
far-IR/sub-mm of extragalactic origin, and the deep explorations from space in
the far-IR and with large millimetric telescopes on ground. These results
challenge those obtained from optical-UV observations, by revealing luminous to
very luminous phases in galaxy evolution at substantial redshifts, likely
corresponding to violent events of star-formation in massive systems. This is
bringing to significant refinements of the present schemes of galaxy formation,
as far as the history of baryon transformations is concerned.

</DOC>
<DOC>
<DOCNO> 122998 </DOCNO>
The DEEP2 Redshift Survey


  The DEIMOS spectrograph is nearing completion in the UC Lick shops and will
be delivered to the Keck Observatory in 2001. Once it is operational, a team of
astronomers will initiate DEEP2, a major redshift survey of galaxies that will
consume approximately 120 nights at the Keck Observatory over a three year
period. Our goal is to gather high-quality spectra of ~60,000 galaxies with
Z>0.7 in order to study the properties and large scale clustering of galaxies
at $Z \approx 1$. The survey will be done at high spectral resolution,
R=\lambda/\Delta \lambda ~3500, allowing us to work between the bright OH sky
emission lines and to infer linewidths for many of the target galaxies. The
linewidth data will facilitate the execution of the classical redshift-volume
cosmological test, which can provide a precision measurement of the equation of
state of the Universe.

</DOC>
<DOC>
<DOCNO> 102596 </DOCNO>
A smooth regularity theorem for nondegenerate CR-mappings


  We prove the following regularity result: If M and M' are smooth generic
submanifolds of C^N and C^N' respectively, where N and N' are not necessarily
equal, and if M is minimal, then every C^k-CR-map from M into M^\prime which is
k-nondegenerate is smooth. As an application, every CR diffeomorphism of
k-nondegenerate minimal submanifolds in C^N of class C^k is smooth.

</DOC>
<DOC>
<DOCNO> 13493 </DOCNO>
Comment on "High Field Quasiparticle Tunneling in


  We show that the negative c-axis magnetoresistance in cuprates is the normal
state feature.

</DOC>
<DOC>
<DOCNO> 117322 </DOCNO>
Positronium atom scattering by H_2 in a coupled-channel framework


  The scattering of ortho positronium (Ps) by H$_2$ has been investigated using
a three-Ps-state [Ps(1s,2s,2p)H$_2($X $^1\Sigma_g^+$)] coupled-channel model
and using Born approximation for higher excitations and ionization of Ps and B
$^1\Sigma_u^+$ and b $^3\Sigma_u^+$ excitations of H$_2$. We employ a recently
proposed time-reversal-symmetric nonlocal electron-exchange model potential. We
present a calculational scheme for solving the body-frame fixed-nuclei
coupled-channel scattering equations for Ps-H$_2$, which simplifies the
numerical solution technique considerably. Ps ionization is found to have the
leading contribution to target-elastic and all target-inelastic processes. The
total cross sections at low and medium energies are in good agreement with
experiment.

</DOC>
<DOC>
<DOCNO> 119436 </DOCNO>
Wide Field Imaging of the Hubble Deep Field-South Region I: Quasar


  We present candidate quasars from a multi-color (uBVRI + narrow-band) imaging
survey of 1/2 square degree around the Hubble Deep Field - South. We identify
154 candidate quasars with B < 23 using color selection, consistent with
previously measured QSO number counts if we assume a 60% selection efficiency.
The narrow-band filter (NB) was centered at 3958 A to detect Ly-alpha at the
redshift of J2233-6033, the HDF-S QSO. We confirm the presence of Ly-alpha
nebulosity extending ~12'' around the HDF-S QSO, reported by Bergeron et al.
(1999). We detect 10 point-like objects in emission through the NB filter. Of
these, 7 satisfy our QSO color selection criteria. One of emission-line objects
is a B~20 radio-quiet quasar at z=1.56, 6.7' from the line of sight to the
HDF-S QSO and ~12'' from the western edge of the WFPC2 deep field.

</DOC>
<DOC>
<DOCNO> 13621 </DOCNO>
Magneto-electronic Properties of a Ferrimagnetic Semiconductor: The


  The mixed manganite-cuprate CaCu3Mn4O12 is found, using density functional
methods, to be a narrow gap (90 meV calculated) ferrimagnetic semiconductor. Cu
(formally S=1/2) antialigns with Mn (formally S=3/2), and the net spin moment
is 9 \mu_B consistent with the formal spins. Holes have Cu d_{xy}-O p_{\sigma}
(i.e. antibonding dp\sigma) character with spins aligned antiparallel to the
net magnetization; electrons have the opposite spin and have mixed Cu d_{xy} -
Mn e_g character. Thermally excited electrons and holes will each be fully spin
polarized, but in opposite directions. The properties of this material are
strongly tied to the distorted quadruple perovskite structure, which is closely
related to the skutterudite structure. The observed resistivity,
magnetoresistance, and magnetization are discussed in terms of our results.

</DOC>
<DOC>
<DOCNO> 120843 </DOCNO>
A Numerical Study of Cosmic Shear Statistics


  We explore the stability of the variance and skewness of the cosmic
gravitational convergence field, using two different approaches: first we
simulate a whole MEGACAM survey (100 sq. degrees). The reconstructed mass map,
obtained from a shear map, shows that the state-of-the-art data analysis
methods can measure weak-lensing statistics at angular scales ranging from 2.5'
to 25'. We looked also at the influence of a varying signal-to-noise ratio over
the shear map (due to local variations of source density) on the mass
reconstruction, by means of Monte-Carlo simulation. The effect at small scales
can easily be corrected-for in most of the relevant cases. These results
enhance the confidence in the capability of future large surveys to measure
accurately cosmologically interesting quantities.

</DOC>
<DOC>
<DOCNO> 40658 </DOCNO>
Semi-hadronic Tau Decays at CLEO


  This contribution reviews several new or updated results on substructure in
semi-hadronic tau decays, recently published by the CLEO Collaboration. These
results are all based on data collected with the CLEO detector at Cornell's
CESR collider, in the reaction $e^+e^-\to \tau^+\tau^-$ at $\sqrt{s} \simeq
10.6$ GeV. Most of these results are based on $\approx 4.3\times 10^6$
$\tau^+\tau^-$ pairs collected with the CLEO II detector between 1990 --- 1995.
Some (where noted) also use $\approx 8.0\times 10^6$ $\tau^+\tau^-$ pairs
collected with the CLEO II.V detector (which includes a silicon vertex detector
and better drift chamber tracking) between 1995 --- 1999.

</DOC>
<DOC>
<DOCNO> 40306 </DOCNO>
Search for Direct CP Violation in $\Xi$ Hyperon Decay


  Using data collected with the CLEO II detector we have performed a search for
direct CP violation in the $\Xi$ hyperon system. CP violation gives rise to an
asymmetry, A, between the parity-violating angular distributions of the decay
chains $\Xi^- \To \Lambda pi^-$, $\Lambda \To p \pi^-$ and $\bar{\Xi}^+ \To
\bar{\Lambda} \pi^+$, $\bar{\Lambda} \To \bar{p} \pi^+$. In the Standard Model,
A is expected to be in the range $10^{-4}$ to $10^{-5}$. If CP violation were
found at a higher level it could indicate the presence of new physics. We find
no evidence for CP violation: A = -0.057 +- 0.064 +- 0.039. We also obtain
$A_{\Xi} = -0.070 +- 0.064 +- 0.045$ and $\alpha_{\bar{\Xi}}=
0.49^{+0.06}_{-0.05} +- 0.10$.

</DOC>
<DOC>
<DOCNO> 99742 </DOCNO>
Invariant Measures and Orbit Closures on Homogeneous Spaces for Actions


  The theorems of M. Ratner, describing the finite ergodic invariant measures
and the orbit closures for unipotent flows on homogeneous spaces of Lie groups,
are extended for actions of subgroups generated by unipotent elements. More
precisely: Let G be a Lie group (not necessarily connected) and Gamma a closed
subgroup of G. Let W be a subgroup of G such that Ad(W) is contained in the
Zariski closure (in the group of automorphisms of the Lie algebra of G) of the
subgroup generated by the unipotent elements of Ad(W). Then any finite ergodic
invariant measure for the action of W on G/Gamma is a homogeneous measure
(i.e., it is supported on a closed orbit of a subgroup preserving the measure).
Moreover, if G/Gamma has finite volume (i.e., has a finite G-invariant
measure), then the closure of any orbit of W on G/Gamma is a homogeneous set
(i.e., a finite volume closed orbit of a subgroup containing W). Both the above
results hold if W is replaced by any subgroup Lambda of W such that W/Lambda
has finite volume.

</DOC>
<DOC>
<DOCNO> 119307 </DOCNO>
On the Formation of Massive Stars by Accretion


  (Abriged) At present, there are two scenarios for the formation of massive
stars: 1) The accretion scenario and 2) The coalescence scenario, which implies
the merging of intermediate mass stars. We examine here some properties of the
first one. We calculate three different sets of birthlines, i.e. tracks
followed by a continuously accreting star. First, three models with a constant
accretion rate ($\dot{M}_{\rm{accr}}$ = $10^{-6}$, $10^{-5}$, $10^{-4}$
M$_{\odot}$ yr$^{-1}$). Then several birthlines following the accretion models
of Bernasconi and Maeder (\cite{BM96}), which have $\dot{M}_{\rm{accr}}$
increasing only slightly with mass. Finally we calculate several birthlines for
which $\dot{M}_{accr} = \dot{M}_{\mathrm{ref}} ({\frac{M}{M_{\odot}}})
^{\phi}$, with values of $\phi$ equal to 0.5, 1.0 and 1.5 and also for
different values of $\dot{M}_{\mathrm{ref}}$. The best fit to the observations
of PMS stars in the HR diagram is achieved for $\phi$ between 1.0 or 1.5 and
for $\dot{M}_{\mathrm{ref}} \simeq 10^{-5}$ M$_{\odot}$ yr$^{-1}$.
Considerations on the lifetimes favour values of $\phi$ equal to 1.5. These
accretion rates do well correspond to those derived from radio and IR
observations of mass outflows. We emphasize the importance of the accretion
scenario for shaping the IMF, and in particular for determining the upper mass
limit of stars. In the accretion scenario, this upper mass limit will be given
by the mass for which the accretion rate is such that the accretion induced
shock luminosity is of the order of the Eddington luminosity.

</DOC>
<DOC>
<DOCNO> 101355 </DOCNO>
Combinatorial formula for Macdonald polynomials, Bethe Ansatz, and


  We give a direct proof of the combinatorial formula for interpolation
Macdonald polynomials by introducing certain polynomials, which we call generic
Macdonald polynomials, which depend on $d$ additional parameters and specialize
to all Macdonald polynomials of degree $d$. The form of these generic
polynomials is that of a Bethe eigenfunction and they imitate, on a more
elementary level, the $R$-matrix construction of quantum immanants.

</DOC>
<DOC>
<DOCNO> 123218 </DOCNO>
Gravitational Lensing - A brief review


  Gravitational lensing has established itself as a valuable tool in many
astrophysical fields in the roughly 20 years of its existence as an
observational science. In this brief review, first the basics of lensing are
introduced. Then it is shown that the two propagation effects, gravitational
lensing and interstellar scintillation, have a number of properties in common.
Finally, various lensing phenomena are discussed with emphasis on recent
observations.

</DOC>
<DOC>
<DOCNO> 100875 </DOCNO>
Shifting Homomorphisms in Quandle Cohomology and Skeins of Cocycle Knot


  Homomorphisms on quandle cohomology groups that raise the dimensions by one
are studied in relation to the cocycle state-sum invariants of knots and
knotted surfaces. Skein relations are also studied.

</DOC>
<DOC>
<DOCNO> 40373 </DOCNO>
Latest Results on Weak Semi-Leptonic Hyperon Decays in KTeV


  The KTeV experiment at Fermilab has finished its $\Xi^0$ semi-leptonic decay
analysis from the 1997 run and presented here are the final numbers for the
branching ratio and form factors. A new run with three times the statistics was
taken in 1999 and a first look at the data shows the quality and consistency of
the results, predicting a similar improvement in these measurements.

</DOC>
<DOC>
<DOCNO> 83433 </DOCNO>
A Formal Framework for Linguistic Annotation (revised version)


  `Linguistic annotation' covers any descriptive or analytic notations applied
to raw language data. The basic data may be in the form of time functions -
audio, video and/or physiological recordings - or it may be textual. The added
notations may include transcriptions of all sorts (from phonetic features to
discourse structures), part-of-speech and sense tagging, syntactic analysis,
`named entity' identification, co-reference annotation, and so on. While there
are several ongoing efforts to provide formats and tools for such annotations
and to publish annotated linguistic databases, the lack of widely accepted
standards is becoming a critical problem. Proposed standards, to the extent
they exist, have focused on file formats. This paper focuses instead on the
logical structure of linguistic annotations. We survey a wide variety of
existing annotation formats and demonstrate a common conceptual core, the
annotation graph. This provides a formal framework for constructing,
maintaining and searching linguistic annotations, while remaining consistent
with many alternative data structures and file formats.

</DOC>
<DOC>
<DOCNO> 100052 </DOCNO>
Random matrix theory over finite fields: a survey


  First we survey generating function methods for obtaining useful probability
estimates about random matrices in the finite classical groups. Then we
describe a probabilistic picture of conjugacy classes which is coherent and
beautiful. Connections are made with symmetric function theory, Markov chains,
potential theory, Rogers-Ramanujan type identities, quivers, and various
measures on partitions.

</DOC>
<DOC>
<DOCNO> 72227 </DOCNO>
Preheating, Thermalization and Supergravity


  This contribution to the proceedings collects new recent results on
preheating after inflation. We discuss tachyonic preheating in the SUSY
motivated hybrid inflation; development of equilibrium after preheating; theory
of fermionic preheating and the problem of gravitino overproduction from
preheating.

</DOC>
<DOC>
<DOCNO> 68695 </DOCNO>
Mu and Tau Neutrino Thermalization and Production in Supernovae:


  We investigate the rates of production and thermalization of $\nu_\mu$ and
$\nu_\tau$ neutrinos at temperatures and densities relevant to core-collapse
supernovae and protoneutron stars. Included are contributions from electron
scattering, electron-positron annihilation, nucleon-nucleon bremsstrahlung, and
nucleon scattering. For the scattering processes, in order to incorporate the
full scattering kinematics at arbitrary degeneracy, the structure function
formalism developed by Reddy et al. (1998) and Burrows and Sawyer (1998) is
employed. Furthermore, we derive formulae for the total and differential rates
of nucleon-nucleon bremsstrahlung for arbitrary nucleon degeneracy in
asymmetric matter. We find that electron scattering dominates nucleon
scattering as a thermalization process at low neutrino energies
($\epsilon_\nu\lesssim 10$ MeV), but that nucleon scattering is always faster
than or comparable to electron scattering above $\epsilon_\nu\simeq10$ MeV. In
addition, for $\rho\gtrsim 10^{13}$ g cm$^{-3}$, $T\lesssim14$ MeV, and
neutrino energies $\lesssim60$ MeV, nucleon-nucleon bremsstrahlung always
dominates electron-positron annihilation as a production mechanism for
$\nu_\mu$ and $\nu_\tau$ neutrinos.

</DOC>
<DOC>
<DOCNO> 119631 </DOCNO>
Stellar indices and kinematics in Seyfert 1 nuclei


  We present spectra of 6 type 1 Seyfert galaxies, 2 Seyfert 2, a starburst
galaxy and a compact narrow line radiogalaxy, taken in two spectral ranges
centered around the near--IR CaII triplet (CaT) (at ~8600 Angstroms), and the
Mgb stellar feature at 5180 Angstroms. We measured the equivalent width (EWs)
of these features and the Fe52 and Fe53 spectral indices. We found that the
strength of the CaT in type 1 Seyfert galaxies with prominent central point
sources, is larger than what would be expected from the observed strength of
the blue indices. This could be explained by the presence of red supergiants in
the nuclei of Seyfert 1 galaxies. On the other hand, the blue indices of these
galaxies could also be diluted by the strong FeII multiplets that can be seen
in their spectra.
  We have also measured the stellar and gas velocity dispersions of the
galaxies in the sample. The stellar velocity dispersions were measured using
both, the Mgb and CaT stellar features. The velocity dispersion of the gas in
the narrow line region (NLR) was measured using the strong emission lines
[OIII] 5007, 4959 and [SIII] 9069. We compare the gas and star velocity
dispersions and find that both magnitudes are correlated in Seyfert galaxies.
Most of the Seyfert 1 we observe have stellar velocity dispersion somehow
greater than that of the gas in the NLR.

</DOC>
<DOC>
<DOCNO> 13225 </DOCNO>
Acoustic radiation in randomly-layered structures


  Radiation from acoustic sources located inside randomly-layered structures is
studied using the transfer matrix method. It is shown that in contrast to the
periodically layered cases where the radiation can be either enhanced or
inhibited depending on the frequency, and the characteristics and the material
composition of the structures, in the random structures the radiation is always
inhibited. The degree of inhibition depends on the acoustic frequency, number
of random layers, and the randomness and acoustic parameters of the structures.
Both spherically and cylindrically random structures are considered. The
results point to the possibility of designing sonic waveguide devices which
will not suffer from the energy loss caused by radiation, thus allowing
effective energy confinement or long-range energy propagation.

</DOC>
<DOC>
<DOCNO> 102762 </DOCNO>
Subtriviality of continuous fields of nuclear C*--algebras


  We extend in this paper the characterisation of a separable nuclear
\cst-algebra given by Kirchberg proving that given a unital separable
continuous field of nuclear C*-algebras A over a compact metrizable space X,
the C(X)-algebra A is isomorphic to a unital C(X)-subalgebra of the trivial
continuous field C(X;O_2), image of C(X;O_2) by a norm one projection.

</DOC>
<DOC>
<DOCNO> 179032 </DOCNO>
Liquid-gas phase transition in nuclei in the relativistic Thomas-Fermi


  The equation of state (EOS) of finite nuclei is constructed in the
relativistic Thomas-Fermi theory using the non-linear $\sigma-\omega -\rho$
model. The caloric curves are calculated by confining the nuclei in the
freeze-out volume taken to be a sphere of size about 4 to 8 times the normal
nuclear volume. The results obtained from the relativistic theory are not
significantly different from those obtained earlier in a non-relativistic
framework. The nature of the EOS and the peaked structure of the specific heat
$C_v$ obtained from the caloric curves show clear signals of a liquid-gas phase
transition in finite nuclei. The temperature evolution of the Gibbs potential
and the entropy at constant pressure indicate that the characteristics of the
transition are not too different from the first-order one.

</DOC>
<DOC>
<DOCNO> 170754 </DOCNO>
Quantum Vernam Cipher


  We discuss aspects of secure quantum communication by proposing and analyzing
a quantum analog of the Vernam cipher (one-time-pad). The quantum Vernam cipher
uses entanglement as the key to encrypt quantum information sent through an
insecure quantum channel. First, in sharp contrast with the classical Vernam
cipher, the quantum key can be recycled securely. We show that key recycling is
intrinsic to the quantum cipher-text, rather than using entanglement as the
key. Second, the scheme detects and corrects for arbitrary transmission errors,
and it does so using only local operations and classical communication (LOCC)
between the sender and the receiver. The application to quantum message
authentication is discussed. Quantum secret sharing schemes with similar
properties are characterized. We also discuss two general issues, the relation
between secret communication and secret sharing, the classification of secure
communication protocols.

</DOC>
<DOC>
<DOCNO> 11895 </DOCNO>
Vortex Structure in Underdoped Cuprates


  In underdoped cuprates the normal state is highly anomalous and is
characterized as a pseudogap phase. The question of how to describe the
``normal'' core of a superconducting vortex is an outstanding open problem. We
show that the SU(2) formulation of the t-J model provides a description of the
normal state as well as the vortex core. Interestingly, the pseudogap persists
inside the core. We also found that it is likely that the core consists of a
state which breaks translational symmetry due to the existence of staggered
current which generate staggered magnetic field with very slow dynamics. This
staggered flux state is likely to be the ground state for magnetic fields
higher than $H_{c2}$. Experiments to test this picture are proposed.

</DOC>
<DOC>
<DOCNO> 151761 </DOCNO>
Low-Energy Effective Action of N=2 Gauge Multiplet Induced by


  We study one-loop effective action of hypermultiplet theory coupled to
external N=2 vector multiplet. We formulate this theory in N=1 superspace and
develop a general approach to constructing derivative expansion of the
effective action based on an operator symbol technique adopted to N=1
supersymmetric field models. The approach under consideration allows to
investigate on a unique ground a general structure of effective action and
obtain both N=2 superconformal invariant (non-holomorphic) corrections and
anomaly (holomorphic) corrections. The leading low-energy contributions to
effective action are found in explicit form.

</DOC>
<DOC>
<DOCNO> 13033 </DOCNO>
Long-range effects in granular avalanching


  We introduce a model for granular flow in a one-dimensional rice pile that
incorporates rolling effects through a long-range rolling probability for the
individual rice grains proportional to $r^{-\rho}$, $r$ being the distance
traveled by a grain in a single topling event. The exponent $\rho$ controls the
average rolling distance. We have shown that the crossover from power law to
stretched exponential behaviors observed experimentally in the granular
dynamics of rice piles can be well described as a long-range effect resulting
from a change in the transport properties of individual grains. We showed that
stretched exponential avalanche distributions can be associated with a
long-range regime for $1<\rho<2$ where the average rolling distance grows as a
power law with the system size, while power law distributions are associated
with a short range regime for $\rho>2$, where the average rolling distance is
independent of the system size.

</DOC>
<DOC>
<DOCNO> 12670 </DOCNO>
Self-Consistent Theory of Rupture by Progressive Diffuse Damage


  We analyze a self-consistent theory of crack growth controlled by a
cumulative damage variable d(t) dependent on stress history. As a function of
the damage exponent $m$, which controls the rate of damage dd/dt \propto
sigma^m as a function of local stress $\sigma$, we find two regimes. For 0 < m
< 2, the model predicts a finite-time singularity. This retrieves previous
results by Zobnin for m=1 and by Bradley and Wu for 0 < m < 2. To improve on
this self-consistent theory which neglects the dependence of stress on damage,
we apply the functional renormalization method of Yukalov and Gluzman and find
that divergences are replaced by singularities with exponents in agreement with
those found in acoustic emission experiments. For m =2 and m > 2, the rupture
dynamics is not defined without the introduction of a regularizing scheme. We
investigate three regularization schemes involving respectively a saturation of
damage, a minimum distance of approach to the crack tip and a fixed stress
maximum. In the first and third schemes, the finite-time singularity is
replaced by a crack dynamics defined for all times but which is controlled by
either the existence of a microscopic scale at which the stress is regularized
or by the maximum sustainable stress. In the second scheme, a finite-time
singularity is again found. In the first two schemes within this regime m > 2,
the theory has no continuous limit.

</DOC>
<DOC>
<DOCNO> 11252 </DOCNO>
How to measure the Bogoliubov quasiparticle amplitudes in a trapped


  We propose an experiment, based on two consecutive Bragg pulses, to measure
the momentum distribution of quasiparticle excitations in a trapped Bose gas at
low temperature. With the first pulse one generates a bunch of excitations
carrying momentum $q$, whose Doppler line is measured by the second pulse. We
show that this experiment can provide direct access to the amplitudes $u_{q}$
and $v_{q}$ characterizing the Bogoliubov transformations from particles to
quasiparticles. We simulate the behavior of the nonuniform gas by numerically
solving the time dependent Gross-Pitaevskii equation.

</DOC>
<DOC>
<DOCNO> 119154 </DOCNO>
The Effect of Hydrostatic Weighting on the Vertical Temperature


  We investigate the effect of hydrostatic scale heights ${\lambda}(T)$ in
coronal loops on the determination of the vertical temperature structure $T(h)$
of the solar corona. Every method that determines an average temperature at a
particular line-of-sight from optically thin emission (e.g. in EUV or soft
X-ray wavelengths) of a mutli-temperature plasma, is subject to the emission
measure-weighted contributions $dEM(T)/dT$ from different temperatures. Because
most of the coronal structures (along open or closed field lines) are close to
hydrostatic equilibrium, the hydrostatic temperature scale height introduces a
height-dependent weighting function that causes a systematic bias in the
determination of the temperature structure $T(h)$ as function of altitude $h$.
The net effect is that the averaged temperature seems to increase with
altitude, $dT(h)/dh > 0$, even if every coronal loop (of a multi-temperature
ensemble) is isothermal in itself. We simulate this effect with differential
emission measure distributions observed by {\sl SERTS} for an instrument with a
broadband temperature filter such as {\sl Yohkoh/SXT} and find that the
apparent temperature increase due to hydrostatic weighting is of order $\Delta
T \approx T_0 \times h/r_{\sun}$. We suggest that this effect largely explains
the systematic temperature increase in the upper corona reported in recent
studies (e.g. by Sturrock et al., Wheatland et al., or Priest et al.), rather
than being an intrinsic signature of a coronal heating mechanism.

</DOC>
<DOC>
<DOCNO> 13761 </DOCNO>
Classical long-range interacting N-particle configurations and its


  We consider classical N-particle system with arbitrary central pair
potential. Mechanical equilibrium condition in spherically-symmetric case leads
to a nonlinear integro-differential equation for concentration n(r). For
special state equation $p=an^{\gamma}(1+bn)$, original integro-differential
equation transforms into purely integral one. Its solution (under b=0) is
written through a row over interaction parameter. Physical conditions for its
convergency is discussed. For power-like potential kernal of integral operator
is calculated in apparent kind. The cases of Coulomb and harmonic potentials
are considered separately up to a third order. General scheme of application of
the theory for some astrophysical and cosmological problems is presented. Model
system with spherical potential pits is considered. By perturbation theory
first virial correction $\delta n$ is calculated.

</DOC>
<DOC>
<DOCNO> 68334 </DOCNO>
Quasi-Localization of Gravity by Resonant Modes


  We examine the behaviour of gravity in brane theories with extra dimensions
in a non-factorizable geometry. We find that for metrics which are
asymptotically flat far from the brane there is a resonant graviton mode at
zero energy. The presence of this resonance ensures quasi-localization of
gravity, whereby at intermediate scales the gravitational laws on the brane are
approximately four dimensional. However, for scales larger than the lifetime of
the graviton resonance the five dimensional laws of gravity will be reproduced
due to the decay of the four dimensional graviton. We also present a simple
classification of the possible types of effective gravity theories on the brane
that can appear for general non-factorizable background theories.

</DOC>
<DOC>
<DOCNO> 7762 </DOCNO>
Multiple scaling regimes in simple aging models


  We investigate aging in glassy systems based on a simple model, where a point
in configuration space performs thermally activated jumps between the minima of
a random energy landscape. The model allows us to show explicitly a subaging
behavior and multiple scaling regimes for the correlation function. Both the
exponents characterizing the scaling of the different relaxation times with the
waiting time and those characterizing the asymptotic decay of the scaling
functions are obtained analytically by invoking a `partial equilibrium'
concept.

</DOC>
<DOC>
<DOCNO> 12619 </DOCNO>
Blackbody radiation in a nonextensive scenario


  An exact analysis of the N-dimensional blackbody radiation process in a
nonextensive \`a la Tsallis scenario is performed for values of the
nonextensive's index in the range ($0<q<1$). The recently advanced ``Optimal
Lagrange Multipliers" (OLM) technique has been employed. The results are
consistent with those of the extensive, $q=1$ case. The generalization of the
celebrated laws of Planck, Stefan-Boltzmann, and Wien are investigated.
  PACS: 05.30.-d, 95.35.+d, 05.70.Ce, 75.10.-b Keywords: Tsallis
Thermostatistics, Blackbody radiation.

</DOC>
<DOC>
<DOCNO> 12971 </DOCNO>
Thermal Fluctuations of Elastic Ring


  We study the effects of thermal fluctuations on a small elastic ring. We
derive analytical expressions for the correlation functions of the Euler
angles, for the real space two--point correlation functions and for the
probability distribution of writhe, as a function of the persistence lengths
that determine the rigidity with respect to bending and twist. Fluctuation
amplitudes diverge in the limit of vanishing twist rigidity. There is crossover
from a small scale regime in which twist and writhe modes are uncoupled, to a
large scale regime in which twist affects the spatial configurations of the
ring.

</DOC>
<DOC>
<DOCNO> 85489 </DOCNO>
Znajek-Damour Horizon Boundary Conditions with Born-Infeld


  In this work, the interaction of electromagnetic fields with a rotating
(Kerr) black hole is explored in the context of Born-Infeld (BI) theory of
electromagnetism instead of standard Maxwell theory and particularly BI theory
versions of the four horizon boundary conditions of Znajek and Damour are
derived. Naturally, an issue to be addressed is then whether they would change
from the ones given in Maxwell theory context and if they would, how.
Interestingly enough, as long as one employs the same local null tetrad frame
as the one adopted in the works by Damour and by Znajek to read out physical
values of electromagnetic fields and fictitious surface charge and currents on
the horizon, it turns out that one ends up with exactly the same four horizon
boundary conditions despite the shift of the electrodynamics theory from a
linear Maxwell one to a highly non-linear BI one. Close inspection reveals that
this curious and unexpected result can be attributed to the fact that the
concrete structure of BI equations happens to be such that it is
indistinguishable at the horizon to a local observer, say, in Damour's local
tetrad frame from that of standard Maxwell theory.

</DOC>
<DOC>
<DOCNO> 117436 </DOCNO>
A Sociological Study of the Optically Emitting Isolated Neutron Stars


  Although less than 1% of all radio pulsars are detected at optical
wavelengths, their optical emission can yield a wealth of information that is
either very difficult or plainly impossible to obtain at other wavelengths.

</DOC>
<DOC>
<DOCNO> 169587 </DOCNO>
Positive Maps Which Are Not Completely Positive


  The concept of the {\em half density matrix} is proposed. It unifies the
quantum states which are described by density matrices and physical processes
which are described by completely positive maps. With the help of the
half-density-matrix representation of Hermitian linear map, we show that every
positive map which is not completely positive is a {\em difference} of two
completely positive maps. A necessary and sufficient condition for a positive
map which is not completely positive is also presented, which is illustrated by
some examples.

</DOC>
<DOC>
<DOCNO> 120334 </DOCNO>
Comptonization in X-ray bright neutron star globular cluster systems


  A BeppoSAX survey of bright Neutron Star (NS) systems in globular clusters,
together with the results obtained on Galactic LMXRB, suggests that a
two-component model is a reasonable description of the 0.1-200 keV spectra. At
energies lower than a few keV, a thermal component dominates, either due to the
direct view of the NS surface, to the emission of the boundary layer, or to a
multi-temperature blackbody originating in the accretion disk. At higher
energies, a power-law with an high-energy cutoff is the likely signature of
thermal Comptonization of soft X-ray photons, probably produced by the same
thermal mechanisms as above. The plasma optical depth (electron temperature)
correlates (anticorrelates) with the X-ray luminosity, suggesting that the
properties of the Comptonizing plasma are driven by the X-ray energy output.

</DOC>
<DOC>
<DOCNO> 11891 </DOCNO>
Transport Properties near the z=2 Insulator-Superconductor Transition


  We consider here the fluctuation conductivity near the point of the
insulator-superconductor transition in a system of regular Josephson junction
arrays in the presence of particle-hole asymmetry or equivalently homogeneous
charge frustration. The transition is characterised by the dynamic critical
exponent $z=2$, opening the possibility of the perturbative
renormalization-group (RG) treatment. The quartic interaction in the
Ginzburg-Landau action and the coupling to the Ohmic heat bath, giving the
finite quasiparticle life-time, lead to the non-monotonic behavior of the dc
conductivity as a function of temperature in the leading logarithmic
approximation.

</DOC>
<DOC>
<DOCNO> 13669 </DOCNO>
Exchange Mediated Interaction of Dislocations and Deformation Hardening


  We propose an explanation of anomalies observed in the behavior of
deformation hardening of Invars. An extremely strong volume magnetostriction,
typical of Invars, results in an enhancement of the exchange contribution to
the energy of the dislocation system by about three orders of magnitude with
respect to its value in conventional ferromagnetics. Both the self energy of
individual dislocations and the interaction between them, determined usually
only by the elastic deformation, in Invars is strongly diminished by the
contribution of the exchange energy. This fact explains a strong suppression of
the deformation hardening rate in the second stage as well as its strong
temperature and content dependence in Invars.

</DOC>
<DOC>
<DOCNO> 122747 </DOCNO>
The central region of M31 observed with XMM-Newton (I. Group properties


  We present the results of a study based on an XMM-Newton Performance
Verification observation of the central 30 arcmin of the nearby spiral galaxy
M31. In the 34-ks European Photon Imaging Camera (EPIC) exposure, we detect 116
sources down to a limiting luminosity of 6 x 10^35 erg/s (0.3--12 keV, d = 760
kpc). The luminosity distribution of the sources detected with XMM-Newton
flattens at luminosities below ~ 2.5 x 10^37 erg/s. We make use of hardness
ratios for the detected sources in order to distinguish between classes of
objects such as super-soft sources and intrinsically hard or highly absorbed
sources. We demonstrate that the spectrum of the unresolved emission in the
bulge of M31 contains a soft excess which can be fitted with a ~ 0.35-keV
optically-thin thermal-plasma component clearly distinct from the composite
point-source spectrum. We suggest that this may represent diffuse gas in the
centre of M31, and we illustrate its extent in a wavelet-deconvolved image.

</DOC>
<DOC>
<DOCNO> 118713 </DOCNO>
Stellar Structure and Evolution: Deductions from Hipparcos


  During the last decade, the understanding of fine features of the structure
and evolution of stars has become possible as a result of enormous progress
made in the acquisition of high-quality observational and experimental data and
of new developments and refinements in the theoretical description of stellar
plasmas. The confrontation of high-quality observations with sophisticated
stellar models has allowed many aspects of the theory to be validated, and
several characteristics of stars relevant to Galactic evolution and cosmology
to be inferred. This paper is a review of the results of recent studies
undertaken in the context of the Hipparcos mission, taking benefit of the
high-quality astrometric data it has provided. Successes are discussed, as well
as the problems that have arisen and suggestions proposed to solve them. Future
observational and theoretical developments expected and required in the field
are also presented.

</DOC>
<DOC>
<DOCNO> 99428 </DOCNO>
Interchanging homotopy limits and colimits in CAT


  Let $I$,$J$ be small categories and $C:I\times J@>>>\CAT$ a functor to the
category of small categories. We show that if $I$ has a final object then the
canonical map
$\operatorname{hocolim}_J\operatorname{holim}_IC@>>>\operatorname{holim}_I
\operatorname{hocolim}_JC$ is a strong homotopy equivalence.

</DOC>
<DOC>
<DOCNO> 14125 </DOCNO>
Slow dynamics near glass transitions in thin polymer films


  The $\alpha$-process (segmental motion) of thin polystyrene films supported
on glass substrate has been investigated in a wider frequency range from
10$^{-3}$ Hz to 10$^4$ Hz using dielectric relaxation spectroscopy and thermal
expansion spectroscopy. The relaxation rate of the $\alpha$-process increases
with decreasing film thickness at a given temperature above the glass
transition. This increase in the relaxation rate with decreasing film thickness
is much more enhanced near the glass transition temperature. The glass
transition temperature determined as the temperature at which the relaxation
time of the $\alpha$-process becomes a macroscopic time scale shows a distinct
molecular weight dependence. It is also found that the Vogel temperature has
the thickness dependence, i.e., the Vogel temperature decreases with decreasing
film thickness. The expansion coefficient of the free volume $\alpha_f$ is
extracted from the temperature dependence of the relaxation time within the
free volume theory. The fragility index $m$ is also evaluated as a function of
thickness. Both $\alpha_f$ and $m$ are found to decrease with decreasing film
thickness.

</DOC>
<DOC>
<DOCNO> 40475 </DOCNO>
Focus Point Supersymmetry: Proton Decay, Flavor and CP Violation, and


  In focus point supersymmetry, all squarks and sleptons, including those of
the third generation, have multi-TeV masses without sacrificing naturalness. We
examine the implications of this framework for low energy constraints and the
light Higgs boson mass. Undesirable contributions to proton decay and electric
dipole moments, generic in many supersymmetric models, are strongly suppressed.
As a result, the prediction for alpha_s in simple grand unified theories is 3
to 5 standard deviations closer to the experimental value, and the allowed
CP-violating phases are larger by one to two orders of magnitude. In addition,
the very heavy top and bottom squarks of focus point supersymmetry naturally
produce a Higgs boson mass at or above 115 GeV without requiring heavy
gauginos. We conclude with an extended discussion of issues related to the
definition of naturalness and comment on several other prescriptions given in
the literature.

</DOC>
<DOC>
<DOCNO> 122298 </DOCNO>
The Metallicity of 0.5<z<1 Field Galaxies


  We have measured the emission line ratios in a sample of 34 CFRS star-forming
galaxies with redshifts between 0.5 < z < 1.0, and computed their metallicities
by means of the empirically-calibrated R_23 metallicity estimator introduced by
Pagel et al. (1979). The current analysis concentrates on the 15 galaxies with
L_Hbeta > 1.2x10^41 erg s-1. Although our results can only be regarded as
preliminary until near-IR spectroscopy of Halpha and [NII]6583 are available,
the metallicities of these galaxies appear to be remarkably similar to those of
local galaxies selected in the same way, and there appears to have been little
change in the relationship between metallicity and line- and
continuum-luminosity from z~1 to today. At this stage our results do not
support the idea that these galaxies, known to be generally small and with
late-type morphologies, are dwarf galaxies brightened by large bursts of
star-formation, as had been suggested from previous studies. Rather, our
findings are more consistent with a picture in which these systems are the
progenitors of today's massive metal-rich galaxies.

</DOC>
<DOC>
<DOCNO> 102467 </DOCNO>
Presenting quantum Schur algebras as quotients of the quantized


  We obtain a presentation of quantum Schur algebras (over the field Q(v)) by
generators and relations. This presentation is compatible with the usual
presentation of the quantized universal enveloping algebra of the Lie algebra
gl(2). We also locate the ``integral'' form of the quantum Schur algebra within
the presented algebra and show it has a basis which is closely related to
Lusztig's basis of the integral form of the quantized enveloping algebra.

</DOC>
<DOC>
<DOCNO> 10678 </DOCNO>
Photoinduced absorption from localized intra-gap states


  A model is developed for photoinduced absorption from localized states
observed in femtosecond pump-probe experiments in high-Tc superconductors and
other materials. The dynamics of localized carriers are described in terms of
phenomenological approach similar to that originaly proposed by Rothwarf and
Taylor. Expanding the relaxation rate in powers of the order parameter we have
shown that density of localized carriers is sensitive to Tc. From the analysis
of the experimental data on YBa2Cu3O(7-x) and K0.3MoO3 we conclude that
significant intra-gap density of localized states exists in these materials.
Temperature dependence of the density of photoexcited localized carriers in
underdoped YBa2Cu3O(7-x) and in K0.3MoO3 is consistent with the observation of
the pseudogap above Tc.

</DOC>
<DOC>
<DOCNO> 8322 </DOCNO>
Robustness of Wave Functions of Interacting Many Bosons in a Leaky Box


  We study the robustness, against the leakage of bosons, of wave functions of
interacting many bosons confined in a finite box, by deriving and analyzing a
general equation of motion for the reduced density operator. We identify a
robust wave function that remains a pure state, whereas other wave functions,
such as the Bogoliubov's ground state and the ground state with a fixed number
of bosons, evolve into mixed states. Although these states all have the
off-diagonal long-range order, and almost the same energy densities, we argue
that only the robust state is realized as a macroscopic quantum state.

</DOC>
<DOC>
<DOCNO> 85544 </DOCNO>
Canonical Theory of 2+1 Gravity


  Recently 2+1 dimensional gravity theory, especially ${\rm AdS_3}$ has been
studied extensively. It was shown to be equivalent to the 2+1 Chern-Simon
theory and has been investigated to understand the black hole thermodynamics,
i.e. Hawking temperature and others. The purpose of this report is to
investigate the canonical formalism of the original 2+1 Einstein gravity theory
instead of the Chern-Simon theory. For the spherically symmetric space-time,
local conserved quantities(local mass and angular momentum) are introduced and
using them canonical quantum theory is defined. Constraints are imposed on
state vectors and solved analytically. The strategy to obtain the solution is
followed by our previous work.

</DOC>
<DOC>
<DOCNO> 84535 </DOCNO>
BTZ black hole from (3+1) gravity


  We propose an approach for constructing spatial slices of (3+1) spacetimes
with cosmological constant but without a matter content, which yields (2+1)
vacuum with $\Lambda$ solutions. The reduction mechanism from (3+1) to (2+1)
gravity is supported on a criterion in which the Weyl tensor components are
required to vanish together with a dimensional reduction via an appropriate
foliation. By using an adequate reduction mechanism from the
Pleba\'nski-Carter[A] solution in (3+1) gravity, the (2+1) BTZ solution can be
obtained.

</DOC>
<DOC>
<DOCNO> 72321 </DOCNO>
Comments on the Holographic Picture of the Randall-Sundrum Model


  We discuss some issues about the holographic interpretation of the compact
Randall-Sundrum model, which is conjectured to be dual to a 4d field theory
with non-linearly realized conformal symmetry. We make several checks of this
conjecture. In particular, we show that the radion couples conformally to a
background 4d metric. We also discuss the interpretation of the Goldberger-Wise
mechanism for stabilizing the radion. We consider situations where the
electroweak breaking stabilizes the radion and we discuss the issue of natural
conservation of flavor quantum numbers.

</DOC>
<DOC>
<DOCNO> 119585 </DOCNO>
New Stars on the Block


  Groups of young stars located in the solar neighborhood have recently
received a lot of attention. These stars, which are $\lesssim$ 10 million years
old, can provide insights into the birth of stars and planetary systems. For
example, the TW Hydrae Association is just at the age when planets are believed
to form, while MBM12 represents an earlier stage. In this Perspective, I
briefly discuss recent research in this field.

</DOC>
<DOC>
<DOCNO> 150848 </DOCNO>
The Two-exponential Liouville Theory and the Uniqueness of the


  It is shown that in the two-exponential version of Liouville theory the
coefficients of the three-point functions of vertex operators can be determined
uniquely using the translational invariance of the path integral measure and
the self-consistency of the two-point functions. The result agrees with that
obtained using conformal bootstrap methods. Reflection symmetry and a
previously conjectured relationship between the dimensional parameters of the
theory and the overall scale are derived.

</DOC>
<DOC>
<DOCNO> 178965 </DOCNO>
Rearranging Pionless Effective Field Theory


  We point out a redundancy in the operator structure of the pionless effective
field theory which dramatically simplifies computations. This redundancy is
best exploited by using dibaryon fields as fundamental degrees of freedom. In
turn, this suggests a new power counting scheme which sums range corrections to
all orders. We explore this method with a few simple observables: the deuteron
charge form factor, n p -> d gamma, and Compton scattering from the deuteron.
Higher dimension operators involving electroweak gauge fields are not
renormalized by the s-wave strong interactions, and therefore do not scale with
inverse powers of the renormalization scale. Thus, naive dimensional analysis
of these operators is sufficient to estimate their contribution to a given
process.

</DOC>
<DOC>
<DOCNO> 67690 </DOCNO>
How open charm production and scaling violations probe the rightmost


  In 1994 Zakharov and the present authors argued that in color dipole (CD)
BFKL approach to DIS excitation of open charm at moderately large Q2 is
dominated by hard BFKL exchange. In view of the rapid accumulation of the
experimental data on small-x charm structure function of the proton F2cc from
HERA, we subject the issue of dominance of the rightmost hard BFKL pole
exchange to further scrutiny. Based on CD BFKL-Regge factorization we report
parameter-free predictions for the charm structure function F2cc and show that
the background to the dominant rightmost hard BFKL exchange from subleading
hard BFKL and soft-pomeron exchanges is negligible small from real
photo-production to DIS at Q2 lsim 50-100 GeV2. The agreement with the
experiment is good and lends strong support for the intercept of the rightmost
hard BFKL pole DeltaPom=alphaPom-1=0.4 as found in 1994 in the color dipole
approach. We comment on the related determination of DeltaPom from the
x-dependence of the longitudinal structure function FL(x,Q2) and of the scaling
violation dF2/dlog Q2 taken at a suitable value of Q2. \

</DOC>
<DOC>
<DOCNO> 11904 </DOCNO>
First Order Transition in the Ginzburg-Landau Model


  The d-dimensional complex Ginzburg-Landau (GL) model is solved according to a
variational method by separating phase and amplitude. The GL transition becomes
first order for high superfluid density because of effects of phase
fluctuations. We discuss its origin with various arguments showing that, in
particular for d = 3, the validity of our approach lies precisely in the first
order domain.

</DOC>
<DOC>
<DOCNO> 174482 </DOCNO>
Antideuteron yield at the AGS and coalescence implications


  We present Experiment 864's measurement of invariant antideuteron yields in
11.5A GeV/c Au + Pt collisions. The analysis includes 250 million triggers
representing 14 billion 10% central interactions sampled for events with high
mass candidates. We find (1/2 pi pt) d^(2)N/dydpt = 3.5 +/- 1.5 (stat.)
+0.9,-0.5 (sys.) x 10^(-8) GeV^(-2)c^(2) for 1.8<y<2.2, <pt>=0.35 GeV/c
(y(cm)=1.6) and 3.7 +/- 2.7 (stat.) +1.4,-1.5 (sys.) x 10^(-8) GeV^(-2)c^(2)
for 1.4<y<1.8, <pt>=0.26 GeV/c, and a coalescence parameter B2-bar of 4.1 +/-
2.9 (stat.) +2.3,-2.4 (sys.) x 10^(-3) GeV^(2)c^(-3). Implications for the
coalescence model and antimatter annihilation are discussed.

</DOC>
<DOC>
<DOCNO> 85445 </DOCNO>
The Weyl anomaly and the nature of the background geometry


  The Weyl anomaly problem is treated within a purely geometrical context.
Arguments are given that hint at a possible classical origin of the conformal
anomaly in the Riemannian nature of the background geometry where the matter
fields play out their dynamics. Some considerations allowing for a possible
resolution of the Weyl anomaly problem are briefly outlined. Following the
spirit of the standard model of the fundamental interactions, it is argued that
the Weyl anomaly should be a consequence of the breaking of the gauge symmetry
at some stage during the evolution of the universe.

</DOC>
<DOC>
<DOCNO> 101877 </DOCNO>
Real Analysis, Quantitative Topology, and Geometric Complexity


  Contents
  1 Mappings and distortion
  2 The mathematics of good behavior much of the time, and the BMO frame of mind
  3 Finite polyhedra and combinatorial parameterization problems
  4 Quantitative topology, and calculus on singular spaces
  5 Uniform rectifiability
  Appendices
  A Fourier transform calculations
  B Mappings with branching
  C More on existence and behavior of homeomorphisms
  D Doing pretty well with spaces which may not have nice coordinates
  E Some simple facts related to homology

</DOC>
<DOC>
<DOCNO> 116250 </DOCNO>
Wavelet Analysis of Solar Activity


  Using wavelet analysis approach, the temporal variations of solar activity on
time scales ranging from days to decades, are examined from the daily time
series of sunspot numbers. A hierarchy of changing complex periods are careful
detected and related cycles compared with results from recent similar analyses.
A general determination of the main Schwabe cycle length variations is also
suggested on the basis of the wavelet amplitude distribution extracted from the
local wavelet power map.

</DOC>
<DOC>
<DOCNO> 99913 </DOCNO>
Resolution graphs of some surface singularities II. (generalized Iomdin


  In this article we give a construction of the resolution graphs of
hypersurface surface singularities (X_k,0) given by generalized Iomdin series.
All these resolution graphs are coordinated by an ``universal bi-colored
graph'' which is associated with the ICIS determining the Iomdin series. The
definition of this new graph is rather involved, and in concrete examples it is
difficult to compute. Nevertheless, we present a large number of examples. This
is very helpful in the exemplification of its properties as well. We then
present a construction of the resolution graphs of the surface singularities
above which uses the "universal bi-coloured graph" and the integer k. This is
formulated in a purely combinatorial algorithm. The result is a highly
non-trivial generalization of the case of cyclic coverings of smooth surfaces.

</DOC>
<DOC>
<DOCNO> 99284 </DOCNO>
Polynomial hulls and H-infinity control for a hypoconvex constraint


  We say that a subset of C^n is hypoconvex if its complement is the union of
complex hyperplanes. Let D be the closed unit disk in C, T the unit circle. We
prove two conjectures of Helton and Marshall. (See ``Frequency domain design
and analytic selections,'' Indiana Univ. Math. J. 39, no. 1 (1990), 157-184.)
Let p:T X C^n --> R+ be a smooth function whose sublevel sets have compact
hypoconvex fibers over T. Then, with some restrictions on p, if Y is the set
where p is less than or equal to 1, the polynomial convex hull of Y is the
union of graphs of analytic vector-valued functions with boundary in Y.
Furthermore, let t be the smallest real number such that the set where p is
less than or equal to t contains the boundary of the graph of some analytic
vector-valued function on the disk. Then there is only one analytic
vector-valued function f such that p(z,f(z)) is less than or equal to t for all
z in T. We show that f is smooth on T. We also prove that if p varies smoothly
with respect to a parameter, so does the unique f just found.

</DOC>
<DOC>
<DOCNO> 101882 </DOCNO>
Multilinear Calder\'on-Zygmund operators on Hardy spaces


  It is shown that multilinear Calder\'on-Zygmund operators are bounded on
products of Hardy spaces.

</DOC>
<DOC>
<DOCNO> 118607 </DOCNO>
Supernovae versus Neutron Star Mergers as the Major r-Process Sources


  I show that recent observations of r-process abundances in metal-poor stars
are difficult to explain if neutron star mergers (NSMs) are the major r-process
sources. In contrast, such observations and meteoritic data on Hf182 and I129
in the early solar system support a self-consistent picture of r-process
enrichment by supernovae (SNe). While further theoretical studies of r-process
production and enrichment are needed for both SNe and NSMs, I emphasize two
possible direct observational tests of the SN r-process model: gamma rays from
decay of r-process nuclei in SN remnants and surface contamination of the
companion by SN r-process ejecta in binaries.

</DOC>
<DOC>
<DOCNO> 39682 </DOCNO>
Model-independent determination of |V_{ub}|


  The decay distribution of the kinematic variable \xi_u in inclusive charmless
semileptonic decays of B mesons is unique. The novel method for a
model-independent determination of |V_{ub}| is described.

</DOC>
<DOC>
<DOCNO> 84821 </DOCNO>
Marzke-Wheeler coordinates for accelerated observers in special


  In special relativity, the definition of coordinate systems adapted to
generic accelerated observers is a long-standing problem, which has found
unequivocal solutions only for the simplest motions. We show that the
Marzke-Wheeler construction, an extension of the Einstein synchronization
convention, produces accelerated systems of coordinates with desirable
properties: (a) they reduce to Lorentz coordinates in a neighborhood of the
observers' world-lines; (b) they index continuously and completely the causal
envelope of the world-line (that is, the intersection of its causal past and
its causal future: for well-behaved world-lines, the entire space-time). In
particular, Marzke-Wheeler coordinates provide a smooth and consistent
foliation of the causal envelope of any accelerated observer into space-like
surfaces.
  We compare the Marzke-Wheeler procedure with other definitions of accelerated
coordinates; we examine it in the special case of stationary motions, and we
provide explicit coordinate transformations for uniformly accelerated and
uniformly rotating observers. Finally, we employ the notion of Marzke-Wheeler
simultaneity to clarify the relativistic paradox of the twins, by pinpointing
the local origin of differential aging.

</DOC>
<DOC>
<DOCNO> 13903 </DOCNO>
Fragmented Condensate Ground State of Trapped Weakly Interacting Bosons


  The ground state and its structure for a rotating, harmonically trapped
N-Boson system with a weak repulsive contact interaction are studied as the
angular momentum L increases up to 3N. We show that the ground state is
generally a fragmented condensate due to angular momentum conservation. In
response to an (arbitrarily weak) asymmetric perturbation of the trap, however,
the fragmented ground state can be transformed into a single condensate state.
We manifest this intrinsic instability by calculating the conditional
probability distributions, which show patterns analogous to the boson density
distributions predicted by mean-field theory.

</DOC>
<DOC>
<DOCNO> 83093 </DOCNO>
Efficient generation of rotating workforce schedules


  Generating high-quality schedules for a rotating workforce is a critical task
in all settings where a certain staffing level must be guaranteed beyond the
capacity of single employees, such as for instance in industrial plants,
hospitals, or airline companies. Results from ergonomics \cite{BEST91} indicate
that rotating workforce schedules have a profound impact on the health and
social life of employees as well as on their performance at work. Moreover,
rotating workforce schedules must satisfy legal requirements and should also
meet the objectives of the employing organization. We describe our solution to
this problem. A basic design decision was to aim at quickly obtaining
high-quality schedules for realistically sized problems while maintaining human
control. The interaction between the decision maker and the algorithm therefore
consists in four steps: (1) choosing a set of lengths of work blocks (a work
block is a sequence of consecutive days of work shifts), (2) choosing a
particular sequence of work and days-off blocks among those that have optimal
weekend characteristics, (3) enumerating possible shift sequences for the
chosen work blocks subject to shift change constraints and bounds on sequences
of shifts, and (4) assignment of shift sequences to work blocks while
fulfilling the staffing requirements. The combination of constraint
satisfaction and problem-oriented intelligent backtracking algorithms in each
of the four steps allows to find good solutions for real-world problems in
acceptable time. Computational results from real-world problems and from
benchmark examples found in the literature confirm the viability of our
approach. The algorithms are now part of a commercial shift scheduling software
package.

</DOC>
<DOC>
<DOCNO> 101908 </DOCNO>
Infinite random matrices and ergodic measures


  We introduce and study a 2-parameter family of unitarily invariant
probability measures on the space of infinite Hermitian matrices. We show that
the decomposition of a measure from this family on ergodic components is
described by a determinantal point process on the real line. The correlation
kernel for this process is explicitly computed.
  At certain values of parameters the kernel turns into the well-known sine
kernel which describes the local correlation in Circular and Gaussian Unitary
Ensembles. Thus, the random point configuration of the sine process is
interpreted as the random set of ``eigenvalues'' of infinite Hermitian matrices
distributed according to the corresponding measure.

</DOC>
<DOC>
<DOCNO> 14038 </DOCNO>
Frequency Scaling of Microwave Conductivity in the Integer Quantum Hall


  We measure the longitudinal conductivity $\sigma_{xx}$ at frequencies $1.246
{\rm GHz} \le f \le 10.05$ GHz over a range of temperatures $235 {\rm mK} \le T
\le 4.2$ K with particular emphasis on the Quantum Hall plateaus. We find that
$Re(\sigma_{xx})$ scales linearly with frequency for a range of magnetic field
around the center of the plateaus, i.e. where $\sigma_{xx}(\omega) \gg
\sigma_{xx}^{DC}$. The width of this scaling region decreases with higher
temperature and vanishes by 1.2 K altogether. Comparison between localization
length determined from $\sigma_{xx}(\omega)$ and DC measurements on the same
wafer show good agreement.

</DOC>
<DOC>
<DOCNO> 120518 </DOCNO>
How to Form (Twin) Globular Clusters?


  Though it is generally assumed that massive molecular clouds are the
progenitors of globular clusters, their detailed formation mechanism is still
unclear. Standard scenarios based on the collapse of a smooth matter
distribution suffer from strong requirements with respect to cluster formation
time scale, binding energy and star formation efficiency. An alternative model
assuming cluster formation due to the recollapse of a supernova-induced,
fragmented shell can relax these difficulties.
    In this paper the final collapse stages of the different scenarios are
compared by N-body simulations for shells and spheres. It is shown that
fragmentation is much more pronounced for shells. Taking a galactic tidal field
into account shells preferably form twin (or multiple) systems, whereas spheres
end up as single clusters. The twins are characterized by identical
metallicities, and stellar mass functions; some of them show counter-rotating
cores. Their orbital evolution can result in both, a final merger or well
separated twins sharing a common galactic orbit.

</DOC>
<DOC>
<DOCNO> 7842 </DOCNO>
Effect of Electron Correlation on the Bragg Reflection


  We study the effect of correlation on the Bragg reflection in the 3D electron
gas, the 1D Luttinger liquid, and the 1D Hubbard model in an alternating
periodic potential at half-filling. In the last system, we suggest a
Luttinger-liquid-type quasi-metallic state in the crossover region from the
band insulator to the Mott insulator. We explain the appearance of this state
in terms of the incompatibility of the Bragg reflection with the concept of
Luttinger liquids.

</DOC>
<DOC>
<DOCNO> 169997 </DOCNO>
Quantum Algorithm for Generalized Deutsch-Jozsa Problem


  We generalize the Deutsch-Jozsa problem and present a quantum algorithm that
can solve the generalized Deutsch-Jozsa problem by a single evaluation of a
given function. We discuss the initialization of an auxiliary register and
present a generalized Deutsch-Jozsa algorithm that requires no initialization
of an auxiliary register.

</DOC>
<DOC>
<DOCNO> 9345 </DOCNO>
Kondo effect in a magnetic field and the magnetoresistivity of Kondo


  The effect of a magnetic field on the spectral density of a $\rm{S=1/2}$
Kondo impurity is investigated at zero and finite temperatures by using
Wilson's numerical renormalization group method. A splitting of the total
spectral density is found for fields larger than a critical value
$H_{c}(T=0)\approx 0.5 T_{K}$, where $T_{K}$ is the Kondo scale. The splitting
correlates with a peak in the magnetoresistivity of dilute magnetic alloys
which we calculate and compare with the experiments on
$\rm{Ce_{x}La_{1-x}Al_{2}}, x=0.0063$. The linear magnetoconductance of quantum
dots exhibiting the Kondo effect is also calculated.

</DOC>
<DOC>
<DOCNO> 178658 </DOCNO>
Complex Scaling of the Faddeev Operator


  The work is devoted to comparison of two different approaches to calculation
of three-body resonances on the basis of the Faddeev differential equations.
The first one is the well known complex scaling approach. The second method is
based on an immediate calculation of the zeros of the scattering matrix
continued to the physical sheet.

</DOC>
<DOC>
<DOCNO> 80819 </DOCNO>
Exact topological density in the lattice Skyrme model


  We propose using the Skyrme model on a lattice as an effective field theory
of meson-baryon interactions. To this end we construct a local topological
density that involves the volumes of tetrahedra in the target space S^3 and we
make use of Coxeter's formula for the Schlafli function to implement it. We
calculate the mean-square radius of a skyrmion in the three-dimensional Skyrme
model, and find some surprises.

</DOC>
<DOC>
<DOCNO> 9110 </DOCNO>
On phase transitions in two-dimensional disordered systems


  The low-energy limits of models with disorder are frequently described by
sigma models. In two dimensions, most sigma models admit either a
Wess-Zumino-Witten or a theta term. When such a term is present the model can
have a stable critical point with gapless excitations. We describe how such a
critical point appears, in particular in two-dimensional superconductors with
disorder. The presence of such terms is required by the underlying (anomalous)
symmetries of the original electron model. This indicates that the usual
symmetry classes of disordered systems in two dimensions can be further
refined. Conversely, our results also indicate that models previously thought
to be in different universality classes are in fact the same once the
appropriate extra terms are included.

</DOC>
<DOC>
<DOCNO> 118426 </DOCNO>
Deep X-Ray Observations of Supernova Remnants G359.1-0.5 and G359.0-0.9


  We present the results of deep ASCA observations of two shell-like radio
supernova remnants (SNRs) located in the direction to the Galactic center (GC)
region. Unlike the radio morphology, G359.1-0.5 shows center-filled X-rays with
prominent K-alpha lines of He-like silicon and H-like sulfur. The plasma
requires at least two temperature components: a silicon-dominated cool plasma
of 0.6keV temperature and a sulfur-dominated higher temperature plasma of
4.4keV. Because the absorption column is ~ 6x10^22 H cm^-2, this SNR would be
near to the GC. The spherical plasma is attributable to supernova ejecta with
the total mass of Si and S being about 0.1 solar mass and 0.3 solar mass,
respectively. X-rays from G359.0-0.9 trace the partial shell structure of the
radio emission. The spectrum is well fitted to a single-temperature plasma of
0.4keV with a non-solar abundance of magnesium or iron. Because the absorption
column is not very large, ~ 1.8x10^22 H cm^-2, G359.0-0.9 would be in front of
the GC region. The total supernova energy, interstellar density near to the
X-ray emitting shell and age of the SNR are estimated to be 1.2x10^51erg,
0.5cm^-3, and 1.8x10^4yr, respectively. We also discuss possible implications
on the origin of the large-scale hot plasma surrounding the GC.

</DOC>
<DOC>
<DOCNO> 7839 </DOCNO>
Excitation Spectra and Thermodynamic Response of Segmented Heisenberg


  The spectral and thermodynamic response of segmented quantum spin chains is
analyzed using a combination of numerical techniques and finite-size scaling
arguments. Various distributions of segment lengths are considered, including
the two extreme cases of quenched and annealed averages. As the impurity
concentration is increased, it is found that (i) the integrated spectral weight
is rapidly reduced, (ii) a pseudo-gap feature opens up at small frequencies,
and (iii) at larger frequencies a discrete peak structure emerges, dominated by
the contributions of the smallest cluster segments. The corresponding
low-temperature thermodynamic response has a divergent contribution due to the
odd-site clusters and a sub-dominant exponentially activated component due to
the even-site segments whose finite-size gap is responsible for the spectral
weight suppression at small frequencies. Based on simple scaling arguments,
approximate low-temperature expressions are derived for the uniform
susceptibility and the heat capacity. These are shown to be in good agreement
with numerical solutions of the Bethe ansatz equations for ensembles of
open-end chains.

</DOC>
<DOC>
<DOCNO> 85020 </DOCNO>
Spin-driven inflation


  Following recent studies of Ford, we suggest -- in the framework of general
relativity -- an inflationary cosmological model with the self-interacting
spinning matter. A generalization of the standard fluid model is discussed and
estimates of the physical parameters of the evolution are given.

</DOC>
<DOC>
<DOCNO> 120236 </DOCNO>
Relation between $\gamma$-rays and emission lines for the $\gamma$-ray


  The relation between the $\gamma$-ray and the emission line luminosities for
a sample of 36 $\gamma$-ray loud blazars is investigated; an apparent
correlation between them, $L_{\gamma} \propto L_{Line}^{0.69\pm0.11}$, with a
correlation coefficient $r=0.741$ and a chance probability of $p =
1.9\times10^{-6}$, is found. It is found, however, that there is no intrinsic
correlation between them: the apparent correlation is due to the redshift
dependence in a flux-limited sample. Thus no evidence is found to support the
argument that the up-scattered soft photons are from the broad emission lines.
Our analysis does not conflict with the SSC model. The disk-jet symbiosis and
radio/$\gamma$-ray correlation found in the literature are also discussed. The
radio/$\gamma$-ray correlation may be an apparent correlation caused by the
boosting effect since both bands are strongly beamed.

</DOC>
<DOC>
<DOCNO> 121577 </DOCNO>
X-Rays from the Nearby Solitary Millisecond Pulsar PSR J0030+0451 - the


  We report on X-ray observations of the solitary 4.8 ms pulsar PSR J0030+0451.
The pulsar was one of the last targets observed in DEC-98 by the ROSAT PSPC.
X-ray pulses are detected on a $4.5\sigma$ level and make the source the
$11^{th}$ millisecond pulsar detected in the X-ray domain. The pulsed fraction
is found to be $69\pm18%$. The X-ray pulse profile is characterized by two
narrow peaks which match the gross pulse profile observed at 1.4 GHz. Assuming
a Crab-like spectrum the X-ray flux is in the range $f_x= 2-3\times 10^{-13}$
erg s$^{-1}$ cm$^{-2} $ ($0.1-2.4$ keV), implying an X-ray efficiency of
$L_x/\dot{E}\sim 0.5-5 \times 10^{-3} (d/0.23 {kpc})^2$.

</DOC>
<DOC>
<DOCNO> 100442 </DOCNO>
On Integrability of the Equations for Nonsingular Pairs of Compatible


  We deal with the problem of description of nonsingular pairs of compatible
flat metrics for the general $N$-component case. We describe the scheme of the
integrating the nonlinear equations describing nonsingular pairs of compatible
flat metrics (or, in other words, nonsingular flat pencils of metrics). It is
based on the reducing this problem to a special reduction of the Lame equations
and the using the Zakharov method of differential reductions in the dressing
method (a version of the inverse scattering method).

</DOC>
<DOC>
<DOCNO> 8658 </DOCNO>
Is the Multichannel Kondo Model Appropriate to Describe the Single


  We investigate the low-temperature dynamics of single electron boxes and
transistors close to their degeneracy point using renormalization group
methods. We show that intermode scattering is a relevant perturbation and
always drives the system to the two-channel Kondo fixed point, where the two
channels correspond to the real spins of the conduction electrons. However, the
crossover temperature T^*, below which Matveev's two-channel Kondo scenario
[K.A. Matveev, Phys. Rev. B 51, 1743 (1995)] develops decreases exponentially
with the number of conduction modes in the tunneling junctions and is extremely
small in most cases. Above T^* the 'infinite channel model' of
Ref.{onlinecite{Schoen}} turns out to be a rather good approximation. We
discuss the experimental limitations and suggest a new experimental setup to
observe the multichannel Kondo behavior.

</DOC>
<DOC>
<DOCNO> 101644 </DOCNO>
A note on sigular limits to hyperbolic systems


  In this note we consider two different singular limits to hyperbolic system
of conservation laws, namely the standard backward schemes for non linear
semigroups and the semidiscrete scheme.
  Under the assumption that the rarefaction curve of the corresponding
hyperbolic system are straight lines, we prove the stability of the solution
and the convergence to the perturbed system to the unique solution of the limit
system for initial data with small total variation.

</DOC>
<DOC>
<DOCNO> 85555 </DOCNO>
The generalized teleparallel structure


  It is proposed to describe a teleparallel structure as a combination of a
Riemannian and a symplectic structure. The correspondent invariance group is an
intersection of the orthogonal and the symplectic groups. For a 4D manifold it
turns to be the basic group of the electro-week interaction $U(1)\times SU(2).$

</DOC>
<DOC>
<DOCNO> 119361 </DOCNO>
Supernovae data: Cosmological Constant or ruling out the Cosmological


  Analysed in the framework of homogeneous FLRW models, the magnitude-redshift
data from high redshift supernovae yield, as a primary result, a strictly
positive cosmological constant. Another reading of the currently published
measurements does not exclude a possible ruling out of the Cosmological
Principle and, thus, also, of the cosmological constant hypothesis. It is shown
how shortly coming data can be used to settle this fondamental issue,
pertaining to both cosmology and particle physics.

</DOC>
<DOC>
<DOCNO> 122426 </DOCNO>
Effects of the X-ray emission from young stars on the ionization level


  We present the initial results of a study aimed at computing the global
effects of the X-ray ionization due to young stars within a molecular cloud
that forms stars with a standard IMF at a rate accelerating with time. We model
the gas distribution of the cloud as a fractal of dimension 2.3. We introduce
the concept of a "Roentgen sphere" as the region around each PMS star where the
ionization rate due to stellar X-rays exceeds that due to interstellar cosmic
rays. Using values of the X-ray luminosity typical of T Tauri stars, we find
that within the Roentgen radius the average ionization rate is increased by a
factor 4 to 20 with respect to the value obtained from cosmic-rays.

</DOC>
<DOC>
<DOCNO> 151929 </DOCNO>
Calibrations and Fayyazuddin-Smith Spacetimes


  We show that a class of spacetimes introduced by Fayyazuddin and Smith to
describe intersecting M5-branes admit a generalized Kahler calibration.
Equipped with this understanding, we are able to construct spacetimes
corresponding to further classes of calibrated $p$-brane world-volume solitons.
We note that these classes of spacetimes also describe the fields of $p$-branes
wrapping certain supersymmetric cycles of Calabi-Yau manifolds.

</DOC>
<DOC>
<DOCNO> 81018 </DOCNO>
Recent Lattice QCD Results from the UKQCD Collaboration


  The lattice technique of studying the strong interaction of matter is used to
obtain predictions of the hadronic spectrum. These simulations were performed
by the UKQCD collaboration using full (unquenched) QCD. Details of the results,
a comparison with quenched data, and novel methods of extracting spectral
properties are described.

</DOC>
<DOC>
<DOCNO> 116827 </DOCNO>
Longitudinal Laser Shaping in Laser Wakefield Accelerators


  We study the energetics of wake excitation during the laser-plasma
interaction in application to laser wakefield accelerators. We find that both
the wake amplitude and the accelerating efficiency (transformer ratio) can be
maximized by properly shaping the longitudinal profile of the driving laser
pulse. The corresponding family of laser pulse shapes is derived in the
nonlinear regime of laser-plasma interaction. Such shapes provide theoretical
upper limit on the magnitude of the wakefield and efficiency by allowing for
uniform photon deceleration inside the laser pulse. We also construct realistic
optimal pulse shapes that can be produced in finite-bandwidth laser systems.

</DOC>
<DOC>
<DOCNO> 117816 </DOCNO>
The Local Interstellar Medium in Puppis-Vela


  The first study of the local interstellar medium (LISM) toward Puppis-Vela (l
= 245\degr to 275\degr, b = -15\degr to +5\degr, d < 200 pc) is presented in
this paper. A study of the locations, sizes, and physical characteristics of
local interstellar gas, i.e. ``astronephography,'' is included, and relies upon
the improved distance measurements provided by Hipparcos parallax measurements.
All spectra of more distant sight lines contain absorption features due to
intervening local gas, and more distant structures can only be studied
accurately if components due to the LISM have been isolated. Towards this end,
high resolution (R ~ 95,000), high signal-to-noise (S/N ~ 110 to 250) Na I
spectra of 11 nearby stars in the direction of Puppis-Vela have been obtained.
Toward Puppis-Vela, absorption due to the LIC was not observed, but components
at three distinct velocities were found, and the extent of the local gas
producing the features was estimated. The conclusions regarding the UV spectrum
of gamma^2 Vel presented by Fitzpatrick & Spitzer (1994) were re-examined in
light of this new LISM data, and the ambiguity in their conclusions about
several absorption components is resolved. The stars in Puppis-Vela flank the
region of the apparent extension of the Local Bubble (or Cavity) known as the
beta CMa tunnel,and measurements of the Na I column density towards the sample
stars have been used to modify existing estimates of the extent of the tunnel.
A compilation of all existing Na I observations of < 200 pc sight lines around
the tunnel reveal that low column densities have been exclusively detected
within l ~ 210\degr to 250\degr,and b ~ -21\degr to -9\degr. Near the Galactic
plane,at latitudes -10\degr < b < 0\degr and d ~< 150 pc, the tunnel is
confined to l < 270\degr, a lower longitude than was previously reported.

</DOC>
<DOC>
<DOCNO> 118061 </DOCNO>
Time Lags in Compact Objects: Constraints on the Emission Models


  Accreting black holes and neutron stars in their hard (low) state show not
only very similar X/gamma-ray spectra but also that the behaviour of their
light curves is quite similar which can be quantified as having similar
power-density spectra and Fourier-frequency-dependent time/phase lags. Taken
together this argues for a common mechanism of the X/gamma-ray production in
these objects. This mechanism is probably a property of the accretion flow only
since it does not depend on the nature of the compact object. In this paper, I
review the observational data paying most attention to the properties of the
temporal variability such as the time/phase lags that hopefully can help us to
discriminate between different theoretical models. I also discuss the models
developed to account for the basic observational facts. Particularly, I show
that the commonly used Compton cloud models with constant temperature cannot
explain variable sources without violating the energy conservation law.
Alternative models where time lags are related to the spectral evolution during
X-ray flares are discussed and compared with observations. Compton reflection
from the outer edge of the accretion disc is shown to markedly affect the time
lag Fourier spectrum.

</DOC>
<DOC>
<DOCNO> 120156 </DOCNO>
Near-infrared probing of embedded structures in starburst and Seyfert


  Surface photometry in the J and K' bands of 15 southern Seyfert or starburst
galaxies is presented. The detailed central morphology and structural
properties of these objects were analyzed by fitting ellipses to isophotes. New
central peculiar structures have been identified like, for instance, three
double-barred systems (ESO 215-G031; ESO 320-G030; ESO 443-G017), one object
with a nested nuclear spiral structure at the center of a primary bar (NGC
5135), one object with a nuclear bar without evidence of a large-scale bar (NGC
4941), and one galaxy with a likely dissolved secondary bar within a primary
one (ESO 508-G005). The J-K' radial profile proved to be reasonably well linked
with the presence of a starburst, but not with the Seyfert activity. For
significant starbursts, the central J-K' value is 0.3-1.5 magnitude larger than
the disc one.

</DOC>
<DOC>
<DOCNO> 116336 </DOCNO>
Equilibrium orbit analysis in a free-electron laser with a coaxial


  An analysis of single-electron orbits in combined coaxial wiggler and axial
guide magnetic fields is presented. Solutions of the equations of motion are
developed in a form convenient for computing orbital velocity components and
trajectories in the radially dependent wiggler. Simple analytical solutions are
obtained in the radially-uniform-wiggler approximation and a formula for the
derivative of the axial velocity $v_{\|}$ with respect to Lorentz factor
$\gamma$ is derived. Results of numerical computations are presented and the
characteristics of the equilibrium orbits are discussed. The third spatial
harmonic of the coaxial wiggler field gives rise to group $III$ orbits which
are characterized by a strong negative mass regime.

</DOC>
<DOC>
<DOCNO> 101795 </DOCNO>
Hankel determinants of Eisenstein series


  In this paper we prove Garvan's conjectured formula for the square of the
modular discriminant $\Delta$ as a 3 by 3 Hankel determinant of classical
Eisenstein series $E_{2n}$. We then obtain similar formulas involving minors of
Hankel determinants for $E_{2r}\Delta^m$, for $m=1,2,3$ and $r=2,3,4,5,7$, and
$E_{14}\Delta^4$. We next use Mathematica to discover, and then the standard
structure theory of the ring of modular forms, to derive the general form of
our infinite family of formulas extending the classical formula for $\Delta$
and Garvan's formula for $\Delta^2$. This general formula expresses the
$n\times n$ Hankel determinant $\det(E_{2(i+j)}(q))_{1\leq i,j\leq n}$ as the
product of $\Delta^{n-1}(\tau)$, a homogeneous polynomial in $E_4^3$ and
$E_6^2$, and if needed, $E_4$. We also include a simple verification proof of
the classical 2 by 2 Hankel determinant formula for $\Delta$. This proof
depends upon polynomial properties of elliptic function parameters from
Jacobi's Fundamenta Nova. The modular forms approach provides a convenient
explanation for the determinant identities in this paper.

</DOC>
<DOC>
<DOCNO> 70828 </DOCNO>
Stochastic GW backgrounds and Ground based detectors


  The interplay between different ground based detectors and stochastic
backgrounds of relic GW is described. A simultaneous detection of GW in the kHz
and in the MHz--GHz region can point towards a cosmological nature of the
signal. The sensitivity of a pair of VIRGO detectors to string cosmological
models is presented. The implications of microwave cavities for stochastic GW
backgrounds are discussed.

</DOC>
<DOC>
<DOCNO> 83387 </DOCNO>
Computing Presuppositions by Contextual Reasoning


  This paper describes how automated deduction methods for natural language
processing can be applied more efficiently by encoding context in a more
elaborate way. Our work is based on formal approaches to context, and we
provide a tableau calculus for contextual reasoning. This is explained by
considering an example from the problem area of presupposition projection.

</DOC>
<DOC>
<DOCNO> 7914 </DOCNO>
Pseudo gap in the density of states in cuprates


  In the framework of the t-J model for cuprates we analyze the development of
a pseudo gap in the density of states (DOS), which at low doping starts to
emerge for temperatures T<J and persists up to the optimum doping. The analysis
is based on numerical results for spectral functions obtained with the
finite-temperature Lanczos method for finite two-dimensional clusters. We find
that the pseudo gap scales with J and is robust also in the presence of nearest
neighbor repulsive interaction. Numerical results are additionally compared
with the self consistent Born approximation (SCBA) results for hole-like
(photoemission) and electron-like (inverse photoemission) spectra at T=0. The
analysis is suggesting that the origin of the pseudo gap is in short-range
antiferromagnetic (AFM) spin correlations and strong asymmetry between the hole
and electron spectra in the underdoped regime.

</DOC>
<DOC>
<DOCNO> 9689 </DOCNO>
Asymptotic states in long Josephson junctions in an external magnetic


  Asymptotic states in long Josephson junctions are investigated in an external
magnetic field. We show that a choice one of the solution of the stationary
Ferrell-Prange equation can carry be out with use of an asymptotic solution of
the sine-Gordon equation and that an evolution to that stable solution occurs
by passing through metastable states, which is determined with a form of
quickly damped initial perturbation. The boundary sine-Gordon and
Ferrell-Prange problems were carried out with a numerical simulation. An
approximated expression for the vortex and antivortex states is obtained in the
case of large values of an external magnetic field.

</DOC>
<DOC>
<DOCNO> 99290 </DOCNO>
Quantum Co-Adjoint Orbits of the Real Diamond Group


  We present explicit formulas for deformation quantization on the co-adjoint
orbits of the real diamond Lie group. From this we obtain quantum half-plans,
quantum hyperbolic cylinders, quantum hyperbolic paraboloids via Fedosov
deformation quantization and finally, the corresponding unitary representations
of this group.

</DOC>
<DOC>
<DOCNO> 67725 </DOCNO>
Spontaneous Symmetry Breaking and Chiral Symmetry


  In this introductory lecture, some basic features of the spontaneous symmetry
breaking are discussed. More specifically, $\sigma $-model, non-linear
realization, and some examples of spontaneous symmetry breaking in the
non-relativistic system are discussed in details. The approach here is more
pedagogical than rigorous and the purpose is to get some simple explanation of
some useful topics in this rather wide area. .

</DOC>
<DOC>
<DOCNO> 150584 </DOCNO>
Loop Variables and Gauge Invariant Interactions - I


  We describe a method of writing down interacting equations for all the modes
of the bosonic open string. It is a generalization of the loop variable
approach that was used earlier for the free, and lowest order interacting
cases. The generalization involves, as before, the introduction of a parameter
to label the different strings involved in an interaction. The interacting
string has thus becomes a ``band'' of finite width. The interaction equations
expressed in terms of loop variables, has a simple invariance that is exact
even off shell. A consistent definition of space-time fields requires the
fields to be functions of all the infinite number of gauge coordinates (in
addition to space time coordinates). The theory is formulated in one higher
dimension, where the modes appear massless. The dimensional reduction that is
needed to make contact with string theory (which has been discussed earlier for
the free case) is not discussed here.

</DOC>
<DOC>
<DOCNO> 121505 </DOCNO>
HST as a powerful astrometric tool for pulsar astronomy


  Given their intrinsic faintness, isolated neutron stars represent an elusive
target for optical astronomy. Up to date, an optical counterpart has been
identified only for a very tiny fraction of the overall population of more than
1000 radio pulsars. The HST contributions to the optical studies of isolated
neutron stars have been recently reviewed by Mignani et al. (2000) and by
Caraveo et al. (these proceedings). Here, we review its specific contribution
in the field of pulsar astrometry and kinematics.

</DOC>
<DOC>
<DOCNO> 10506 </DOCNO>
Equilibration and Dynamic Phase Transitions of a Driven Vortex Lattice


  We report on the observation of two types of current driven transitions in
metastable vortex lattices. The metastable states, which are missed in usual
slow transport measurements, are detected with a fast transport technique in
the vortex lattice of undoped
 2H-NbSe$_2$. The transitions are seen by following the evolution of these
states when driven by a current. At low currents we observe an equilibration
transition from a metastable to a stable state, followed by a dynamic
crystallization transition at high currents.

</DOC>
<DOC>
<DOCNO> 170363 </DOCNO>
Atom Chip for Transporting and Merging Magnetically Trapped Atom Clouds


  We demonstrate an integrated magnetic ``atom chip'' which transports cold
trapped atoms near a surface with very high positioning accuracy.
Time-dependent currents in a lithographic conductor pattern create a moving
chain of magnetic potential wells; atoms are transported in these wells while
remaining confined in all three dimensions. We achieve fluxes up to 10^6 /s
with a negligible heating rate. An extension of this ``atomic conveyor belt''
allows the merging of magnetically trapped atom clouds by unification of two
Ioffe-Pritchard potentials. Under suitable conditions, the clouds merge without
loss of phase space density. We demonstrate this unification process
experimentally.

</DOC>
<DOC>
<DOCNO> 13919 </DOCNO>
Terrace-Width Distributions and Step-Step Repulsions on Vicinal


  For more than three decades, measurement of terrace width distributions
(TWDs) of vicinal crystal surfaces have been recognized as arguably the best
way to determine the dimensionless strength $\tilde{A}$ of the elastic
repulsion between steps. For sufficiently strong repulsions, the TWD is
expected to be Gaussian, with $\tilde{A}$ varying inversely with the squared
variance. However, there has been a controversy over the proportionality
constant. From another perspective the TWD can be described as a continuous
generalized Wigner distribution (CGWD) essentially no more complicated than a
Gaussian but a much better approximation at the few calibration points where
exact solutions exist. This paper combines concisely the experimentally most
useful results from several earlier papers on this subject and describes some
advancements that are in progress regarding numerical tests and in using
Schr\"odinger-equation formalism to give greater understanding of the origin of
the CGWD and to give hope of extensions to more general interaction potentials
between steps. There are many implications for future experiments.

</DOC>
<DOC>
<DOCNO> 102427 </DOCNO>
Sets of singular restrictions of symplectic forms


  Let $\Omega$ be a non-singular syplectic form on some vector space $V$.
Denote by $S^{n}_{k}(\Omega)$ the set of all $k$-dimensional planes $s$ in $V$
such that the restriction of $\Omega$ onto $s$ is singular. For the cases when
$k=2,n-2$ a simple geometric characteristic of $S^{n}_{k}(\Omega)$ will be
described.

</DOC>
<DOC>
<DOCNO> 10141 </DOCNO>
Quasiparticle Localization in Disordered d-Wave Superconductors


  An extensive numerical study is reported on disorder effect in
two-dimensional d-wave superconductors with random impurities in the unitary
limit. It is found that a sharp resonant peak shows up in the density of states
at zero energy and correspondingly the finite-size spin conductance is strongly
enhanced which results in a non-universal feature in one-parameter scaling.
However, all quasiparticle states remain localized, indicating that the
resonant density peak alone is not sufficient to induce delocalization. In the
weak disorder limit, the localization length is so long that the spin
conductance at small sample size is close to the universal value predicted by
Lee (Phys. Rev. Lett. {\bf 71}, 1887 (1993)).

</DOC>
<DOC>
<DOCNO> 68537 </DOCNO>
Perturbative and non-perturbative aspects of moments of the thrust


  Resummation and power-corrections play a crucial role in the phenomenology of
event-shape variables like the thrust T. Previous investigations showed that
the perturbative contribution to the average thrust is dominated by gluons of
small invariant mass, of the order of 10% of Q, where Q is the center-of-mass
energy. The effect of soft gluons is also important, leading to a
non-perturbative 1/Q correction. These conclusions are based on renormalon
analysis in the single dressed gluon (SDG) approximation. Here we analyze
higher moments of the thrust distribution using a similar technique. We find
that the characteristic gluon invariant mass contributing to <(1-T)^m>
increases with m. Yet, for m=2 this scale is quite low, around 27% of Q, and
therefore renormalon resummation is still very important. On the other hand,
the power-correction to <(1-T)^2> from a single soft gluon emission is found to
be highly suppressed: it scales as 1/Q^3. In practice, <(1-T)^2> and higher
moments depend also on soft gluon emission from configurations of three hard
partons, which may lead to alpha_s(Q^2)/Q power-corrections. This issue is yet
to be investigated.

</DOC>
<DOC>
<DOCNO> 70560 </DOCNO>
On the finiteness of N=8 quantum supergravity


  We describe the constraints imposed on quantum maximal supergravity theories
in perturbation theory by the two duality frameworks: S-duality in superstring
theory and the AdS/CFT holographic correspondence between IIB superstring
theory and N=4 super Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 116353 </DOCNO>
Enhanced photoinduced nematic reorientation in mixture with


  The optically induced reorientation of nematic liquid crystal doped with
azo-dye substituted polymer is investigated measuring photoinduced
birefringence. These measurement reveal the value (Dn~0.1) of induced
birefringence of liquid crystal with dye polymer which significantly exceeds
the value of birefringence previously obtained in nematic mixture with the low
molecular weight dye. More than one order of enhancement is connected with
lower diffusivity of polymer.

</DOC>
<DOC>
<DOCNO> 70580 </DOCNO>
Lepton Transmutations from a Rotating Mass Matrix


  Fermion mass matrices generally rotate in generation space under scale
changes, which can lead to fermions of different generations transmuting into
one another. The effect is examined in detail and its cross-section calculated
for $\gamma + \ell_\alpha \longrightarrow \gamma + \ell_\beta$ with
$\ell_\alpha \neq \ell_\beta$ the charged leptons $e, \mu$, or $\tau$. For the
(conventional) Standard Model, this is weak and probably undetectable, though
with some notable exceptions. But for the Dualized Standard Model, which we
advocate and have already used quite successfully to explain quark mixing and
neutrino oscillation, the effect is larger and could be observable. Estimates
of transmutational decays are also given.

</DOC>
<DOC>
<DOCNO> 102131 </DOCNO>
Geometrical properties of sections of Buchsbaum-Rim sheaves


  In this survey article we want to discuss a way of constructing
arithmetically Gorenstein varieties of high codimension. Consider kernel
sheaves B_G of general, generically surjective morphisms G between decomposable
bundles on P^n. The top-dimensional part of the zero-locus of a regular section
of B_G is Gorenstein if B_G has odd rank.
  We show how to implement the construction method in the computer algebra
system Singular and produce some examples of Gorenstein curves and threefolds
in P^6. Finally, we investigate a class of sheaves B_G, where the degeneracy
locus of G does not have the expected codimension.

</DOC>
<DOC>
<DOCNO> 40410 </DOCNO>
Measurements of Parity-Violation Parameters at SLD


  We present direct measurements of the parity-violation parameters $A_b$,
$A_c$, and $A_s$ at the $Z^0$ resonance with the SLD detector. The measurements
are based on approximately 530k hadronic $Z^0$ events collected in 1993-98.
Obtained results are $A_b = 0.914\pm0.024$ (SLD combined: preliminary), $A_c =
0.635\pm0.027$ (SLD combined: preliminary), and $A_s = 0.895\pm0.066(stat.)\pm
0.062(sys.)$.

</DOC>
<DOC>
<DOCNO> 174514 </DOCNO>
Determination of Azimuthal Anisotropy of Neutral Pions from the Measured


  A method is suggested to deduce the anisotropy in neutral pions by measuring
the azimuthal anisotropy of photons in ultra-relativistic nuclear collisions.
The ratio of the estimated anisotropy in photons to the anisotropy in neutral
pions is seen to scale with a parameter which depends on photon multiplicity
and anisotropy. This parameter can be determined from experimental data.

</DOC>
<DOC>
<DOCNO> 118848 </DOCNO>
Fluctuations in Isothermal Spheres


  Isolated isothermal spheres of N gravitationally interacting points with
equal mass are believed to be stable when density contrasts do not exceed 709.
That stability limit does, however, not take into consideration fluctuations of
temperature near the onset of instability. These are important when N is
finite. Here we correlate {\it global mean quadratic temperature fluctuations}
with onset of instability. We show that such fluctuations trigger instability
when the density contrast reaches a value near $709\cdot\exp(-3.3N^{-1/3})$.
These lower values of limiting density contrasts are significantly smaller than
709 when N is not very big and this suggests (i) that numerical calculations
with small N may not reflect correctly the onset of core collapse in clusters
with big N and (ii) that a greater number of globular clusters than is normally
believed may already be in an advanced stage of core collapse because most of
observed globular clusters whose parameters fit quasi-isothermal configurations
are close to marginal stability.

</DOC>
<DOC>
<DOCNO> 122831 </DOCNO>
Cepheid Calibration of the Peak Brightness of SNe Ia. X. SN 1991T in NGC


  Repeated imaging observations have been made of NGC 4527 with the Hubble
Space Telescope between April and June 1999, over an interval of 69 days.
Images were obtained on 12 epochs in the F555W band and on five epochs in the
F814W band. The galaxy hosted the type Ia supernova SN1991T, which showed
relatively unusual behavior by having both an abnormal spectrum near light
maximum, and a slower declining light curve than the proto-typical Branch
normal SNe Ia.
  A total of 86 variables that are putative Cepheids have been found, with
periods ranging from 7.4 days to over 70 days. From photometry with the DoPHOT
program, the de-reddened distance modulus is determined to be (m-M)_0 = 30.67
+/- 0.12 (internal uncertainty) using a subset of the Cepheid data whose
reddening and error parameters are secure. A parallel analysis of the Cepheids
using photometry with ROMAFOT yields (m -M)_0 =30.82 +/- 0.11. The final
adopted modulus is (m -M)_0 =30.74 +/- 0.12 +/- 0.12 (d=14.1 +/- 0.8 +/- 0.8
Mpc).
  The photometric data for SN1991T are used in combination with the Cepheid
distance to NGC 4527 to obtain the absolute magnitude for this supernova of
M_V^0(max) = -19.85 +/- 0.29. The relatively large uncertainty is a result of
the range in estimates of the reddening to the supernova. Thus SN1991T is seen
to be only moderately brighter (by ~ 0.3 mag) than the mean for
spectroscopically normal supernovae, although magnitude differences of up to
0.6 mag cannot be ruled out.

</DOC>
<DOC>
<DOCNO> 118065 </DOCNO>
Observational Constraints to the Evolution of Massive Stars


  We consider some aspects of the evolution of massive stars which can only be
elucidated by means of "indirect" observations, i.e. measurements of the
effects of massive stars on their environments. We discuss in detail the early
evolution of massive stars formed in high metallicity regions as inferred from
studies of HII regions in external galaxies.

</DOC>
<DOC>
<DOCNO> 150957 </DOCNO>
Perturbative Beta Function of N=2 Super Yang-Mills Theories


  An algebraic proof of the nonrenormalization theorem for the perturbative
beta function of the coupling constant of N=2 Super Yang-Mills theory is
provided. The proof relies on a fundamental relationship between the N=2
Yang-Mills action and the local gauge invariant polynomial Tr phi^2, phi(x)
being the scalar field of the N=2 vector gauge multiplet. The
nonrenormalization theorem for the beta function follows from the vanishing of
the anomalous dimension of Tr phi^2.

</DOC>
<DOC>
<DOCNO> 69395 </DOCNO>
New constraints on neutrino physics from Boomerang data


  We have performed a likelihood analysis of the recent data on the Cosmic
Microwave Background Radiation (CMBR) anisotropy taken by the Boomerang
experiment. We find that this data places a strong upper bound on the radiation
density present at recombination. Expressed in terms of the equivalent number
of neutrino species the $2\sigma$ bound is N_nu < 13, and the standard model
prediction, N_nu = 3.04, is completely consistent the the data. This bound is
complementary to the one found from Big Bang nucleosynthesis considerations in
that it applies to any type of radiation, i.e. it is not flavour sensitive. It
also applies to the universe at a much later epoch, and as such places severe
limits on scenarios with decaying neutrinos. The bound also yields a firm upper
limit on the lepton asymmetry in the universe.

</DOC>
<DOC>
<DOCNO> 11144 </DOCNO>
Piezoelectricity and Piezomagnetism : Duality in Two-Dimensional


  The duality approach in 2-{\it dim} two-component regular checkerboards was
extended onto piezoelectricity and piezomagnetism problems. There are found a
relation for effective piezoelectric and piezomagnetic modules for the
checkerboard with $p6^{\prime} mm^{\prime}$-plane symmetry group ({\em
dichromatic triangle}).
  \pacs{Pacs: 73.50.Bk,Jt, 75.70.Ak, 77.65.-j, 77.84.Lf}

</DOC>
<DOC>
<DOCNO> 102044 </DOCNO>
On quantization of r-matrices for Belavin-Drinfeld Triples


  We suggest a formula for quantum universal $R$-matrices corresponding to
quasitriangular classical $r$-matrices classified by Belavin and Drinfeld for
all simple Lie algebras. The $R$-matrices are obtained by twisting the standard
universal $R$-matrix.

</DOC>
<DOC>
<DOCNO> 152172 </DOCNO>
Transcribing spacetime data into matrices


  In certain supergravity backgrounds, D0 branes may polarize into higher
dimensional Dp branes. We study this phenomenon in some generality from the
perspective of a local inertial observer and explore polarization effects
resulting from tidal-like forces. We find D2 brane droplets made of D0 branes
at an extremum of the Born-Infeld action even in scenarios where the RR fields
may be zero. These solutions lead us to a local formulation of the UV-IR
correspondence. A holographic Planck scale bound on the number of D0 branes
plays an important role in the analysis. We focus on the impact of higher order
moments of background fields and work out extensions of the non-commutative
algebra beyond the Lie and Heisenberg structures. In this context, it appears
that q-deformed algebras come into play.

</DOC>
<DOC>
<DOCNO> 151675 </DOCNO>
Reissner-Nordstrom Black Hole in Gravity Localized Models


  We investigate the possibility of having the electrically charged
Reissner-Nordstrom black hole in the gravity localized models in a brane world.
It is shown that the Reissner-Nordstrom black hole exists as a solution in the
5D Randall-Sundrum domain wall model if there is the U(1) bulk gauge field. We
find that the charged black hole is localized on a 3-brane even if zero mode of
the bulk gauge field is not in general localized on the brane in the domain
wall model. Moreover, we extend these observations to the higher-dimensional
topological defect models with codimension more than one in a general
space-time dimension such as the string-like defect model with codimension 2 in
six dimensions and the monopole-like defect model with codimension 3 in seven
dimensions e.t.c.

</DOC>
<DOC>
<DOCNO> 8699 </DOCNO>
Vortex-glass phases in type-II superconductors


  A review is given on the theory of vortex-glass phases in impure type-II
superconductors in an external field. We begin with a brief discussion of the
effects of thermal fluctuations on the spontaneously broken U(1) and
translation symmetries, on the global phase diagram and on the critical
behaviour. Introducing disorder we restrict ourselves to the experimentally
most relevant case of weak uncorrelated randomness which is known to destroy
the long-ranged translational order of the Abrikosov lattice in three
dimensions. Elucidating possible residual glassy ordered phases, we distinguish
betwee positional and phase-coherent vortex glasses. The discussion of elastic
vortex glasses, in two and three dimensions occupy the main part of our review.
In particular, in three dimensions there exists an elastic vortex-glass phase
which still shows quasi-long-range translational order: the `Bragg glass'. It
is shown that this phase is stable with respect to the formation of
dislocations for intermediate fields. Preliminary results suggest that the
Bragg-glass phase may not show phase-coherent vortex-glass order. The latter is
expected to occur in systems with weak disorder only in higher dimensions. We
further demonstrate that the linear resistivity vanishes in the vortex-glass
phase. The vortex-glass transition is studied in detail for a superconducting
film in a parallel field. Finally, we review some recent developments
concerning driven vortex-line lattices moving in a random environment.

</DOC>
<DOC>
<DOCNO> 151395 </DOCNO>
S-Duality from OM-Theory


  We study the compactification of OM-theory on tori and show a simple
heuristic derivation of the $S$-duals of noncommutative open string theory in
diverse dimensions from the OM-theoretical point of view. In particular, we
identify the $S$-duality between noncommutative open string theory and
noncommutative Yang-Mills theory in $(3+1)$ dimensions as the exchange of two
circles of a torus on which OM-theory is compactified. Also, we briefly discuss
$T$-duality between noncommutative open string theories.

</DOC>
<DOC>
<DOCNO> 116692 </DOCNO>
Successive approximations for charged particle motion


  Single particle dynamics in electron microscopes, ion or electron
lithographic instruments, particle accelerators, and particle spectrographs is
described by weakly nonlinear ordinary differential equations. Therefore, the
linear part of the equation of motion is usually solved and the nonlinear
effects are then found in successive order by iteration methods. A Hamiltonian
nature of these equations can lead to simplified computations of particle
transport through an optical device when a suitable computational method is
used. Many ingenious microscopic and lithographic devices were found by H. Rose
and his group due to the simple structure of the eikonal method. In the area of
accelerator physics the eikonal method has never become popular. Here I will
therefore generalize the eikonal method and derive it from a Hamiltonian quite
familiar to the accelerator physics community. With the event of high energy
polarized electron beams and plans for high energy proton beams, nonlinear
effects in spin motion have become important in high energy accelerators. I
will introduce a successive approximation for the nonlinear effects in the
coupled spin and orbit motion of charged particles which resembles some of the
simplifications resulting from the eikonal method for the pure orbit motion.

</DOC>
<DOC>
<DOCNO> 70570 </DOCNO>
Tau neutrino magnetic moments from the Super-Kamiokande and $\nu$


  Combined results on $\nu_{\mu}\to \nu_{\tau}$ oscillations and $\nu
e$-scattering from the Super-Kamiokande and LAMPF experiments, respectively,
limit the Dirac $\nu_{\tau}$ diagonal magnetic moment to $\mu_{\nu_{\tau}} <
1.9\times 10^{-9} \mu_{B}$. For the scheme with 3 Majorana neutrinos the LAMPF
results allow the limitation of effective $\nu_{\tau}$ magnetic moment to
$\mu_{\nu_{\tau}} < 7.6 \times 10^{-10}\mu_{B}$. The moments in the scheme with
additional Majorana light sterile neutrinos as well as experiments on
stimulated radiative neutrino conversion are also discussed.

</DOC>
<DOC>
<DOCNO> 117380 </DOCNO>
On the Formation of Jets


  The phenomenology of jets associated with a variety of black hole systems is
summarized, emphasizing the constraints imposed on their origin. Models of jet
formation are reviewed, focusing in particular on recent ideas concerning MHD
models. Finally, the potential for advancing our understanding of jets both
through future observations - especially forthcoming X-ray missions - and for
elucidating some crucial theoretical questions is highlighted.

</DOC>
<DOC>
<DOCNO> 117653 </DOCNO>
Radio Pulsar Death Line Revisited: Is PSR J2144-3933 Anomalous?


  We reinvestigate the radio pulsar ``death lines'' within the framework of two
different types of polar cap acceleration models, i.e., the vacuum gap model
and the space-charge-limited flow model, with either curvature radiation or
inverse Compton scattering photons as the source of pairs. General relativistic
frame-dragging is taken into account in both models. We find that the inverse
Compton scattering induced space-charge-limited flow model can sustain strong
pair production in some long-period pulsars, which allows the newly detected
8.5s pulsar PSR J2144-3933 to be radio loud, without assuming a special neutron
star equation-of-state or ad hoc magnetic field configurations.

</DOC>
<DOC>
<DOCNO> 71905 </DOCNO>
HELAC-PHEGAS: automatic computation of helicity amplitudes and cross


  HELAC-PHEGAS is a FORTRAN based package that is able to compute automatically
and efficiently tree-order helicity amplitudes and cross sections for arbitrary
scattering processes within the standard electroweak theory and QCD. The
algorithm for the amplitude computation, HELAC, exploits the virtues of the
Dyson-Schwinger equations. The phase-space generation algorithm, PHEGAS,
constructs all possible kinematical mappings dictated by the amplitude under
consideration. Combined with mutichannel self-optimized Monte Carlo integration
it results to efficient cross section evaluation.

</DOC>
<DOC>
<DOCNO> 102533 </DOCNO>
Knotting of algebraic curves in complex surfaces


  A non-singular connected algebraic curve $A$ in a simply connected algebraic
surface $X$ can be knotted so that its homology class and the fundamental group
of its complement in $X$ is preserved, provided $A$ is sufficiently complex
(not too ``rigid'').
  For example, it is true if $A$ admits a degeneration to an irreducible curve
$A_0$ having a unique singularity of the type $X_9$ (a non-degenerate quadriple
point), or more complicated one, and $A.A>16$.
  This generalizes the previous result of the author which concerns the curves
in $CP^2$ of degree $d>4$ (the old preprint is included as a part of the
current one).

</DOC>
<DOC>
<DOCNO> 170674 </DOCNO>
Schrodinger's Cataplex


  We discuss elementary entwiners that cross-weave the variables of certain
integrable models: Liouville, sine-Gordon, and sinh-Gordon field theories in
two-dimensional spacetime, and their quantum mechanical reductions. First we
define a complex time parameter that varies from one energy-shell to another.
Then we explain how field propagators can be simply expressed in terms of
elementary functions through the combination of an evolution in this complex
time and a duality transformation.

</DOC>
<DOC>
<DOCNO> 12168 </DOCNO>
Spin dynamics in Cuprates and its relation to superconductivity


  The relevance of magnetism for the mechanism responsible for high-temperature
superconductivity remains an open and still interesting issue. The observation
by inelastic neutron scattering of strong antiferromagnetic dynamical
correlations in superconducting cuprates is discussed in relation to the
unusual physical properties of the cuprates as well as in relation to the
superconducting pairing.

</DOC>
<DOC>
<DOCNO> 71812 </DOCNO>
Matter profile effect in neutrino factory


  We point out that the matter profile effect --- the effect of matter density
fluctuation on the baseline --- is very important to estimate the parameters in
a neutrino factory with a very long baseline. To make it clear, we propose the
method of the Fourier series expansion of the matter profile. By using this
method, we can take account of both the matter profile effect and its
ambiguity. For very long baseline experiment, such as L=7332km, in the analysis
of the oscillation phenomena we need to introduce a new parameter $ a_{1} $---
the Fourier coefficient of the matter profile --- as a theoretical parameter to
deal with the matter profile effects.

</DOC>
<DOC>
<DOCNO> 122430 </DOCNO>
Modelling Horizontal Air Showers Induced by Cosmic Rays


  We present a framework for the study of muon density patterns on the ground
due to showers produced in the atmosphere by cosmic rays incident at high
zenith angles. As a checking procedure predictions of a model based on such a
framework are compared to simulation results.

</DOC>
<DOC>
<DOCNO> 101677 </DOCNO>
Extensions of Higgs Bundles


  We prove a Hitchin-Kobayashi correspondence for extensions of Higgs bundles.
The results generalize known results for extensions of holomorphic bundles.
Using Simpson's methods, we construct moduli spaces of stable objects. In an
appendix we construct Bott-Chern forms for Higgs bundles

</DOC>
<DOC>
<DOCNO> 13688 </DOCNO>
Onset Temperature of Slow Dynamics in Glass Forming Liquids


  The behaviour of a model glass forming liquid is analyzed for a range of
densities, with a focus on the temperature interval where the liquid begins to
display non-Arrhenius temperature dependence of relaxation times. Analyzing the
dynamics along with properties of local potential energy minima sampled by the
liquid, a crossover or onset temperature $T_s$ is identified below which the
liquid manifests {\it slow dynamics}, and a change in the character of typical
local potential energy minima.

</DOC>
<DOC>
<DOCNO> 169610 </DOCNO>
Limitations on the Creation of Maximal Entanglement


  We study a limited set of optical circuits for creating near maximal
polarisation entanglement {\em without} the usual large vacuum contribution.
 The optical circuits we consider involve passive interferometers, feed-forward
detection, down-converters and squeezers. For input vacuum fields we find that
the creation of maximal entanglement using such circuits is impossible when
conditioned on two detected auxiliary photons. So far, there have been no
experiments with more auxiliary photons. Thus, based on the minimum complexity
of the circuits required, if near maximal polarisation entanglement is possible
it seems unlikely that it will be implemented experimentally with the current
resources.

</DOC>
<DOC>
<DOCNO> 119928 </DOCNO>
A spectroscopic study of field BHB star candidates


  New spectroscopic observations (R=15000 and 40000) are given for 31 nearby (V
< 11) BHB star candidates. IUE low-resolution spectra are available for most of
them. New determinations of temperature, gravity, reddening and abundances were
obtained from these data using models computed by Castelli with an updated
version of the ATLAS9 code. A summary of the visual photometry for these stars
(including new photometry obtained at Kitt Peak) is also given. All 31
candidates are halo stars. We classify 28 as BHB stars because: (1) They lie
close to the ZAHB (in a similar position to globular cluster BHB stars) in the
Teff vs. log g plot. (2) Their distribution of vsini (less than 40 km/s) is
similar to that found for the BHB stars in globular clusters. (3) Their [Fe/H]
lies between -0.99 and -2.95 (mean [Fe/H] -1.67, dispersion 0.42 dex) which is
similar to that found for field halo RR Lyrae and red HB stars but more metal-
poor than for halo globular clusters. Field BHB stars with Teff greater than
8500 K show the He I (4471 A) line corresponding to solar abundance. (4) They
show a similar average enhancement of the alpha-elements ([Mg/Fe] = +0.43 +/-
0.04 and [Ti/Fe] = +0.44 +/- 0.02) to that found for other halo field stars of
similar metallicity. Comments are given on a further 25 stars that have
previously been suggested to be BHB stars; these were not included in our
sample because they did not fulfil one or more of the above criteria.

</DOC>
<DOC>
<DOCNO> 120944 </DOCNO>
Morphological Number Counts of Galaxies in the Hubble Deep Field South


  We present a study of photometric properties of the galaxies in the Hubble
Deep Field South (HDFS) based on the released WFPC2 images obtained with the
Hubble Space Telescope (HST). We have classified about 340 galaxies with $I<26$
mag in the HDFS as well as about 400 galaxies in the Hubble Deep Field North
(HDFN) using the visual classification supplemented by inspection of the
surface brightness profiles of the galaxies. Galaxy population statistics and
morphological number counts for the HDFS are found to be similar to be those
for the HDFN. We have also determined photometrically the redshifts of the
galaxies with $I<26$ mag in the HDFS and the HDFN using the empirical training
set method. Redshift distribution, color-redshift relation, and
magnitude-redshift for each type of galaxies are investigated.

</DOC>
<DOC>
<DOCNO> 150849 </DOCNO>
Towards a SDLCQ test of the Maldacena Conjecture


  We consider the Maldacena conjecture applied to the near horizon geometry of
a D1-brane in the supergravity approximation and present numerical results of a
test of the conjecture against the boundary field theory calculation using
DLCQ. We previously calculated the two-point function of the stress-energy
tensor on the supergravity side; the methods of Gubser, Klebanov, Polyakov, and
Witten were used. On the field theory side, we derived an explicit expression
for the two-point function in terms of data that may be extracted from the
supersymmetric discrete light cone quantization (SDLCQ) calculation at a given
harmonic resolution. This yielded a well defined numerical algorithm for
computing the two-point function. For the supersymmetric Yang-Mills theory with
16 supercharges that arises in the Maldacena conjecture, the algorithm is
perfectly well defined; however, the size of the numerical computation
prevented us from obtaining a numerical check of the conjecture. We now present
numerical results with approximately 1000 times as many states as we previously
considered. These results support the Maldacena conjecture and are within
$10-15%$ of the predicted numerical results in some regions. Our results are
still not sufficient to demonstrate convergence, and, therefore, cannot be
considered to a numerical proof of the conjecture. We present a method for
using a ``flavor'' symmetry to greatly reduce the size of the basis and discuss
a numerical method that we use which is particularly well suited for this type
of matrix element calculation.

</DOC>
<DOC>
<DOCNO> 152315 </DOCNO>
Weyl Invariant p-brane and Dp-brane actions


  Conformal invariant new forms of $p$-brane and D$p$-brane actions are
proposed. The field content of these actions are: an induced metric, gauge
fields, an auxiliary metric and an auxiliary scalar field that implements the
Weyl invariance. This scalar field transforms with a conformal weight that
depends on the brane dimension. The proposed actions are Weyl invariant in any
dimension and the elimination of the auxiliary metric and the scalar field
reproduces the Nambu-Goto action for $p$-branes and the Born-Infeld action for
D$p$-branes. As a consequence of the fact that in the $p$-brane case, the
action is quadratic in $\partial_0 X$, we develop a complete construction for
the associated canonical formalism, solving the problem in previous
formulations of conformal $p$-brane actions where the Hamiltonian can not be
constructed. We obtain the algebra of constraints and identify the generator of
the Weyl symmetry. In the construction of the corresponding supersymmetric
generalization of this conformal $p$-brane action we show that the associated
$\kappa$-symmetry is consistent with the conformal invariance. In the
D$p$-brane case, the actions are quadratic in the gauge fields. These actions
can be used to construct new conformal couplings in any dimension $p$ to the
auxiliary scalar field now promoted as a dynamical variable.

</DOC>
<DOC>
<DOCNO> 71256 </DOCNO>
Prompt photons at RHIC


  We calculate the inclusive cross section for prompt photon production in
heavy-ion collisions at RHIC energies ($\sqrt{s}=130$ GeV and $\sqrt{s}=200$
GeV) in the central rapidity region including next-to-leading order,
$O(\alpha_{em}\alpha_s^2)$, radiative corrections, initial state nuclear
shadowing and parton energy loss effects. We show that there is a significant
suppression of the nuclear cross section, up to $\sim 30%$ at $\sqrt{s}=200$
GeV, due to shadowing and medium induced parton energy loss effects. We find
that the next-to-leading order contributions are large and have a strong $p_t$
dependence.

</DOC>
<DOC>
<DOCNO> 11645 </DOCNO>
Periodic thin-film interference filters as one-dimensional photonic


  We review photonic band gap related properties of a simple periodic system of
thin dielectric layers. Properties associated with forbidden and allowed bands
of such one-dimensional photonic crystals are presented. A revision of
forbidden bands properties leads to an omnidirectional Bragg mirror design. The
anisotropy of allowed bands suggests the formation of photon-focusing caustics
in one-dimensional photonic crystals.

</DOC>
<DOC>
<DOCNO> 99642 </DOCNO>
The degree of the divisor of jumping rational curves


  For a semistable reflexive sheaf $E$ of rank $r$ and $c_1=a$ on $\P^n$ and an
integer $d$ such that $r|ad$, we give sufficient conditions so that the
restriction of $E$ on a generic rational curve of degree $d$ is balanced, i.e.
a twist of the trivial bundle (for instance, if $E$ has balanced restriction on
a generic line, or $r=2$ or $E$ is an exterior power of the tangent bundle).
Assuming this, we give a formula for the 'virtual degree', interpreted
enumeratively, of the locus of rational curves of degree $d$ on which the
restriction of $E$ is not balanced, generalizing a classical formula due to
Barth for the degree of the divisor of jumping lines of a semistable rank-2
bundle.

</DOC>
<DOC>
<DOCNO> 116684 </DOCNO>
Nuclear Reaction Rates in a Plasma: The Effect of Highly Damped Modes


  The fluctuation-dissipation theorem is used to evaluate the screening factor
of nuclear reactions due to the electromagnetic fluctuations in a plasma. We
show that the commonly used Saltpeter factor is obtained if only fluctuations
near the plasma eigenfrequency are assumed to be important (\omega \sim
\omega_{pe}\ll T (\hbar=k_{B}=1)). By taking into account all the fluctuations,
the highly damped ones, with \omega >\omega_{pe}, as well as those with
\omega\leq\omega_{pe}, we find that nuclear reaction rates are higher than
those obtained using the Saltpeter factor, for many interesting plasmas.

</DOC>
<DOC>
<DOCNO> 122326 </DOCNO>
The Snake - a Reconnecting Coil in a Twisted Magnetic Flux Tube


  We propose that the curious Galactic Center filament known as ``The Snake''
is a twisted giant magnetic flux tube, anchored in rotating molecular clouds.
The MHD kink instability generates coils in the tube and subsequent magnetic
reconnection injects relativistic electrons. Electrons diffuse away from a coil
at an energy-dependent rate producing a flat spectral index at large distances
from it. Our fit to the data of \citet{gray95a} shows that the magnetic field
$\sim 0.4 \> \rm mG$ is large compared to the ambient $\sim 7 \mu \> \rm G$
field, indicating that the flux tube is force-free. If the {\em relative} level
of turbulence in the Snake and the general interstellar medium are similar,
then electrons have been diffusing in the Snake for about $3 \times 10^5 \> \rm
yr$, comparable to the timescale at which magnetic energy is annihilated in the
major kink. Estimates of the magnetic field in the G359.19-0.05 molecular
complex are similar to our estimate of the magnetic field in the Snake
suggesting a strong connection between the physics of the anchoring molecular
regions and the Snake. We suggest that the physical processes considered here
may be relevant to many of the radio filaments near the Galactic Center. We
also suggest further observations of the Snake and other filaments that would
be useful for obtaining further insights into the physics of these objects.

</DOC>
<DOC>
<DOCNO> 14105 </DOCNO>
Algebraic Fermi liquid from phase fluctuations: "topological" fermions,


  Within the phase fluctuation model for the pseudogap state of cuprate
superconductors we identify a novel statistical "Berry phase" interaction
between the nodal quasiparticles and fluctuating vortices. The effective action
describing this model assumes the form of an anisotropic Euclidean quantum
electrodynamics in (2+1) dimensions (QED_3) and naturally generates the
marginal Fermi liquid behavior for its fermionic excitations. The doping axis
in the x-T phase diagram emerges as a quantum critical line which regulates low
energy fermiology. We examine the merits of our theory in light of available
experiments.

</DOC>
<DOC>
<DOCNO> 14110 </DOCNO>
Staggered Currents in the Vortex Core


  We study the electronic structure of the vortex core in the cuprates using
the U(1) slave-boson mean-field wavefunctions and their Gutzwiller projection.
We conclude that there exists local orbital antiferromagnetic order in the core
near optimal doping. We compare the results with that of BCS theory and analyze
the spatial dependence of the local tunneling density of states.

</DOC>
<DOC>
<DOCNO> 100961 </DOCNO>
Value Functions for Bolza Problems with Discontinuous Lagrangians and


  We investigate the value function of the Bolza problem of the Calculus of
Variations $$
  V (t,x)=\inf \{\int_{0}^{t} L (y(s),y'(s))ds + \phi(y(t)) : y \in W^{1,1}
(0,t; R^n) ; y(0)=x \}, $$ with a lower semicontinuous Lagrangian $L$ and a
final cost $\phi$, and show that it is locally Lipschitz for $t>0$ whenever $L$
is locally bounded. It also satisfies Hamilton-Jacobi inequalities in a
generalized sense.
  When the Lagrangian is continuous, then the value function is the unique
lower semicontinuous solution to the corresponding Hamilton-Jacobi equation,
while for discontinuous Lagrangian we characterize the value function by using
the so called contingent inequalities.

</DOC>
<DOC>
<DOCNO> 120575 </DOCNO>
Placing limits on the spin-torsion fluctuation from the stability of


  The gravitational stability of Friedmann metric with respect to homogeneous
and isotropic perturbations in Einstein-Cartan cosmology is used together with
the COBE data to place a limit on the spin-torsion primordial density
fluctuation.Cosmological perturbations in Bianchi type III models are shown to
have no contributions from torsion at the early stages of the Universe.

</DOC>
<DOC>
<DOCNO> 119594 </DOCNO>
What Does It Take to Stabilize Gravitational Clustering?


  An analytical understanding of the strongly nonlinear regime of gravitational
collapse has been difficult to achieve. The only insight has been the stable
clustering hypothesis, which assumes that the number of neighbors for objects
averaged over small length scales is constant in time. Our recently proposed
analytic halo model for N-point correlation functions now provides a tool for
calculating gravitational clustering properties in the strongly nonlinear
regime. This model also provides a new physical framework for an independent
evaluation of the validity of the stable clustering hypothesis. We derive the
asymptotic nonlinear behavior of the N-point correlation functions and pairwise
peculiar velocities in terms of dark matter halo properties. We show that these
statistics exhibit stable clustering only when the halo mass function and halo
density profile obey specific relations. The long-cherished stable clustering
hypothesis therefore is not necessarily realized in practice.

</DOC>
<DOC>
<DOCNO> 121602 </DOCNO>
On the uncertainty of hyperon couplings and the electrochemical


  Uncertainty of the hyperon couplings, in particular, that of the $\Sigma^-$,
in dense matter raises the question of the behavior of the electrochemical
potential in neutron star matter, which is crucial to the possible presence of
the kaon condensed phase. We show that regardless of this uncertainty, the
$\Lambda$ hyperon, whose coupling can be constrained by its binding in nuclear
matter and other observations, also aided by the $\Xi^-$, introduce a
saturation of the electrochemical potential just as the $\Sigma^-$ would
otherwise do, which tends to mitigate against kaon condensation. The maximum
possible mass of neutron stars appears to be $\sim 1.5 \msun$ independent of
the uncertainties.

</DOC>
<DOC>
<DOCNO> 170561 </DOCNO>
Feynman Clocks, Casual Networks, and the Origin of Hierarchical 'Arrows


  A theory of 'time' as a form of 'information' is proposed. New tools such as
Feynman Clocks, Collective Excitation Networks, Sequential Excitation Networks,
Plateaus of Complexity, and Causal Networks are used to unify previously
separate 'arrows of time'.

</DOC>
<DOC>
<DOCNO> 12079 </DOCNO>
Impurity-induced Ferromagnetism in Doped Triplet Excitonic Insulator


  The theory of impurities in excitonic insulator is investigated in the light
of the recent experiments on hexaborides. First, we study the bound state
around the impurity and find that the bound state emerges when ${Re}\Delta$ is
positive. Second, we study the continuum state using Abrikosov-Gor'kov's
approach. We find that the energy gap is reduced strongly when ${Im}\Delta=0$.
Finally, we solve Bogoliubov-de Gennes equations for excitonic insulator
numerically. We get the results consistent with the analytic ones.
  We also find that incomplete ferromagnetism appears in doped triplet
excitonic insulator with impurity. We make a short qualitative discussion on
the ferromagnetism of doped hexaborides using our result.

</DOC>
<DOC>
<DOCNO> 120253 </DOCNO>
Discovery of hard X-ray emission from Type II bursts of the Rapid


  We report on results of BeppoSAX Target Of Opportunity (TOO) observations of
the source MXB 1730-335, also called the Rapid Burster (RB), made during its
outburst of February-March 1998. We monitored the evolution of the spectral
properties of the RB from the outburst decay to quiescence. During the first
TOO, the X-ray light curve of the RB showed many Type II bursts and its
broadband (1-100 keV) spectrum was acceptably fit with a two blackbody plus
power law model. Moreover, to our knowledge, this is the first time that this
source is detected beyond 30 keV.

</DOC>
<DOC>
<DOCNO> 13440 </DOCNO>
Charged particles in external fields as physical examples of


  We present a unified treatment of three cases of quasi-exactly solvable
problems, namely, charged particle moving in Coulomb and magnetic fields, for
both the Schr\"odinger and the Klein-Gordon case, and the relative motion of
two charged particles in an external oscillator potential. We show that all
these cases are reducible to the same basic equation, which is quasi-exactly
solvable owing to the existence of a hidden $sl_2$ algebraic structure. A
systematic and unified algebraic solution to the basic equation using the
method of factorization is given. Analytic expressions of the energies and the
allowed frequencies for the three cases are given in terms of the roots of one
and the same set of Bethe ansatz equations.

</DOC>
<DOC>
<DOCNO> 122178 </DOCNO>
EUV and X-ray observations of Abell 2199: a three-phase intracluster


  Various independent ways of constraining key cosmological parameters yielded
a consensus range of values which indicates that at the present epoch the bulk
of the universe's baryons is in the form of a warm ($\sim$ 10$^6$ K) gas - a
temperature regime which renders them difficult to detect. The discovery of EUV
and soft X-ray excess emission from clusters of galaxies was originally
interpreted as the first direct evidence for the large scale presence of such a
warm component. We present results from an EUVE Deep Survey (DS) observation of
the rich cluster Abell 2199 in the Lex/B (69 - 190 eV) filter passband. The
soft excess radial trend (SERT), shown by a plot against cluster radius $r$ of
the percentage EUV emission $\eta$ observed above the level expected from the
hot intracluster medium (ICM), behaves as a simple function of $r$ which
decreases monotonically towards $r = 0$; it smoothly turns negative at $r \sim$
6 arcmin, inwards of this radius the EUV is absorbed by cold matter with a
line-of-sight column density of $\geq$ 2.7 $\times$ 10$^{19}$ cm$^{-2}$. The
centre of absorption is offset from that of the emission by $\sim$ 1 arcmin,
and the area involved is much larger than that of the cooling flow. These facts
together provide strong evidence for a centrally concentrated but cluster-wide
distribution of clumps of cold gas which co-exist with warm gas of similar
spatial properties. Further, the simultaneous modeling of EUV and X-ray data
requires a warm component even within the region of absorption. The phenomenon
demonstrates a three phase ICM, with the warm phase estimated to be $\sim$ 5-10
times more massive than the hot.

</DOC>
<DOC>
<DOCNO> 12742 </DOCNO>
Optical absorption in semiconductor quantum dots: Nonlocal effects


  The optical absorption of a single spherical semiconductor quantum dot in an
electrical field is studied taking into account the nonlocal coupling between
the field of the light and the polarizability of the semiconductor. These
nonlocal effects lead to a small size anf field dependent shift and broadening
of the excitonic resonance which may be of interest in future high precision
experiments.

</DOC>
<DOC>
<DOCNO> 169802 </DOCNO>
Transfer of nonclassical features in quantum teleportation via a mixed


  Quantum teleportation of a continuous-variable state is studied for the
quantum channel of a two-mode squeezed vacuum influenced by a thermal
environment. Each mode of the squeezed vacuum is assumed to undergo the same
thermal influence. It is found that when the mixed two-mode squeezed vacuum for
the quantum channel is separable, any nonclassical features, which may be
imposed in an original unknown state, cannot be transferred to a receiving
station. A two-mode Gaussian state, one of which is a mixed two-mode squeezed
vacuum, is separable if and only if a positive well-defined $P$ function can be
assigned to it. The fidelity of teleportation is considered in terms of the
noise factor given by the imperfect channel. It is found that quantum
teleportation may give more noise than direct transmission of a field under the
thermal environment, which is due to the fragile nature of quantum entanglement
of the quantum channel.

</DOC>
<DOC>
<DOCNO> 121238 </DOCNO>
Optical follow-up of the REFLEX survey: a new perspective in cluster


  After the completion of the catalogue built with ESO key program (REFLEX), we
are beginning to explore the multiband optical characteristics of a subsample
of those clusters selected in a statistically independent way. We have already
observed in B, V, R, 9 of the about 50 clusters of the subsample, with 0.15 \le
z \le 0.18. More time has been allocated by ESO for our project in March 2001.
We will therefore be able to compare X-ray and optical morphologies and
luminosities and, thanks to the large field of view of the WFI instrument,
assess the luminosity function and the color segregation in the cluster on a
robust statistical basis. In this poster we present the project, the technical
problems we are facing in the reduction phase, and show the first preliminary
results, which seem very encouraging.

</DOC>
<DOC>
<DOCNO> 85124 </DOCNO>
Magnetic Deformation of Magnetars for the Giant Flares of the Soft


  We present one possible mechanism for the giant flares of the Soft Gamma-Ray
Repeaters (SGRs) within the framework of magnetar, i.e., superstrongly
magnetized neutron star model, motivated by the positive period increase
associated with the August 27 event from SGR 1900+14. From the second-order
perturbation analysis of the equilibrium of the magnetic polytrope, we find
that there exist different equilibrium states separated by the energy of the
giant flares and the shift in the moment of inertia to cause the period
increase. This suggests that, if we assume that the global reconfiguration of
the internal magnetic field of $H\simg 10^{16}$ G suddenly occurs, the positive
period increase $\Delta P_t/P_t \sim 10^{-4}$ as well as the energy $\simg
10^{44}$ ergs of the giant flares may be explained. The moment of inertia can
increase with a release of energy, because the star shape deformed by the
magnetic field can be prolate rather than oblate. In this mechanism, since the
oscillation of the neutron star will be excited, a pulsation of $\sim$ ms
period in the burst profile and an emission of the gravitational waves are
expected. The gravitational waves could be detected by the planned
interferometers such as LIGO, VIRGO and LCGT.

</DOC>
<DOC>
<DOCNO> 121648 </DOCNO>
The Fossil Starburst in M82


  (Abridged) We present high-resolution HST imaging in the optical (WFPC2) and
near-infrared (NICMOS) of a disk region 1 kpc NE of the starburst core in the
nearby galaxy M82. This region, M82 ``B,'' has been suspected to be a fossil
starburst site in which an intense episode of star formation occurred over 100
Myr ago, and our new observations confirm this intepretation. We find a large,
evolved system of super star clusters in M82 B; we identify a total of 113
super star cluster candidates. The clusters range in absolute magnitude from
M_V^0 = -6 to -10, with a peak at -7.5. The derived age distribution suggests
steady, continuing cluster formation at a modest rate at early times (> 2 Gyr
ago), followed by a concentrated formation episode ~600 Myr ago and more recent
suppression of cluster formation. The peak episode coincides with independent
dynamical estimates for the last tidal encounter with M81. Our J and H band
observations resolve the bright giant population in M82's disk for the first
time. Star formation evidently continued in M82 B until about 20-30 Myr ago,
but none is found associated with the youngest generations in the nuclear
starburst (age <= 15 Myr). After correcting the cluster luminosity function to
a fiducial age of 50 Myr, we find that the bright end is characterized by a
power-law slope with alpha = -1.2 +/- 0.3. Cluster sizes (2.34 <= Reff <= 10
pc, or 2.4 <= Rcore <= 7.9 pc) and estimated masses (a median of 10^5 Msun) are
consistent with values found for young super star cluster populations in M82's
core and other galaxies and with the progenitors of globular clusters.

</DOC>
<DOC>
<DOCNO> 71779 </DOCNO>
Neutrino Astrophysics


  A general overview of neutrino physics and astrophysics is given, starting
with a historical account of the development of our understanding of neutrinos
and how they helped to unravel the structure of the Standard Model. We discuss
why it is so important to establish if neutrinos are massive and introduce the
main scenarios to provide them a mass. The present bounds and the positive
indications in favor of non-zero neutrino masses are discussed, including the
recent results on atmospheric and solar neutrinos. The major role that
neutrinos play in astrophysics and cosmology is illustrated.

</DOC>
<DOC>
<DOCNO> 7658 </DOCNO>
Soft spin waves in the low temperature thermodynamics of


  We present a detailed magnetothermal study of Pr(0.7)Ca(0.3)MnO(3), a
perovskite manganite in which an insulator-metal transition can be driven by
magnetic field, but also by pressure, visible light, x-rays, or high currents.
We find that the field-induced transition is associated with an enormous
release of energy which accounts for its strong irreversibility. In the
ferromagnetic metallic state, specific heat and magnetization measurements
indicate a much smaller spin wave stiffness than that seen in any other
manganite, which we attribute to spin waves among the ferromagnetically ordered
Pr moments. The coupling between the Pr and Mn spins may also provide a basis
for understanding the low temperature phase diagram of this most unusual
manganite.

</DOC>
<DOC>
<DOCNO> 40586 </DOCNO>
Quantum Mechanics of Neutrino Oscillations


  We present a simple but general treatment of neutrino oscillations in the
framework of quantum mechanics using plane waves and intuitive wave packet
principles when necessary. We attempt to clarify some confusing statements that
have recently appeared in the literature.

</DOC>
<DOC>
<DOCNO> 121921 </DOCNO>
Tests of Gaussianity of CMB maps


  We study two different methods to test Gaussianity in CMB maps. One of them
is based on the partition function and the other on the morphology of hot and
cold spots. The partition function contains information on all the moments and
scales, being a useful quantity to compress the large data sets expected from
future space missions like Planck. In particular, it contains much richer
information than the one available through the radiation power spectrum. The
second method utilizes morphological properties of hot and cold spots such as
the eccentricity and number of spots in CMB maps. We study the performance of
both methods in detecting non-Gaussian features in small scale CMB simulated
maps as those which will be provided by the Planck mission.

</DOC>
<DOC>
<DOCNO> 8282 </DOCNO>
Ultimate Depth Resolution and Profile Reconstruction in Sputter


  New developments in quantitative sputter depth profiling during the past ten
years are reviewed, with special emphasis on the experimental achievement of
ultrahigh depth resolution (below 2 nm for sputtered depths larger than 10 nm).
In this region, the depth resolution function generally is asymmetric
(i.e.non-Gaussian) and it is governed by the three fundamental parameters:
atomic mixing length, roughness and information depth. The so called
mxing-roughness-information depth (MRI)-model and its application to the
quantitative reconstruction of the in-depth distribution of composition, with a
typical accuracy of one monolayer and better, is demonstrated for SIMS and AES
depth profiles. Based on the combination of the above three parameters, the
ultimate depth resolution is predicted to be about 0.7-1.0 nm. Up to now,
values of 1.4-1.6 nm have been reported, and the use of low energy molecular
ions, e.g. by using sulfur hexafluoride as sputtering gas, has recently pushed
the mixing length down to 0.4-0.6 nm. However, particularly in depth profiling
of multilayers, it can be shown that minimizing the rouhgness parameter,
including the straggling of the mixing length, is most important for the
achievement of the ultimate depth resolution.

</DOC>
<DOC>
<DOCNO> 70876 </DOCNO>
Supersymmetry and Quantum Cosmology


  The development of the N = 4 supersymmetric approach to quantum cosmology
based on the non-compact global O(d,d) symmetries of the effective action is
given. The N = 4 supersymmetric action whose bosonic sector is invariant under
O(d,d) is determined. A representation for supercharges is obtained and the
form of the zero and one-fermion quantum states leading to the Wheeler-DeWitt
equation is found.The development of the N = 4 supersymmetric approach to
quantum cosmology based on the non-compact global O(d,d) symmetries of the
effective action is given. The N = 4 supersymmetric action whose bosonic sector
is invariant under O(d,d) is determined. A representation for supercharges is
obtained and the form of the zero and one-fermion quantum states leading to the
Wheeler-DeWitt equation is found.

</DOC>
<DOC>
<DOCNO> 100055 </DOCNO>
Frobenius and Mashke type Theorems for Doi-Hopf modules and entwined


  We study when induction functors (and their adjoints) between categories of
Doi-Hopf modules and, more generally, entwined modules are separable, resp.
Frobenius. We present a unified approach, leading to new proofs of old results
by the authors, as well as to some new ones. Also our methods provide a
categorical explanation for the relationship between separability and Frobenius
properties.

</DOC>
<DOC>
<DOCNO> 12959 </DOCNO>
Topological invariants for projection method patterns


  We analyze and compare different dynamical systems and groupoids which can be
obtained from projection point patterns. We define the cohomology of a point
pattern as the cocycle cohomology of the pattern groupoid. We describe this
cohomology qualitatively and calculate it for canonical projection method
tilings with codimension smaller or equal than 3.

</DOC>
<DOC>
<DOCNO> 150775 </DOCNO>
Consistency Conditions for Holographic Duality


  We show that if the beta functions of a field theory are given by the
gradient of a certain potential on the space of couplings, a gravitational
background in one more dimension can express the renormalization group (RG)
flow of the theory. The field theory beta functions and the gradient flow
constraint together reconstruct the second order spacetime equations of motion.
The RG equation reduces to the conventional gravitational computation of the
spacetime quasilocal stress tensor, and a c-theorem holds true as a consequence
of the Raychaudhuri equation. Conversely, under certain conditions, if the RG
evolution of a field theory possesses a monotonic c-function, the flow of
couplings can be expressed in terms of a higher dimensional gravitational
background.

</DOC>
<DOC>
<DOCNO> 99318 </DOCNO>
Exactness and the Novikov Conjecture


  We study the connection between the condition that the reduced C*-algebra of
a finitely presented group is exact and the Novikov conjecture holding. The
main result states that if the group is strongly exact in the sense that the
inclusion of the group C*-algebra into the uniform Roe algebra of the group is
a nuclear embedding then the Novikov conjecture holds for that group.

</DOC>
<DOC>
<DOCNO> 100976 </DOCNO>
Classification of Okamoto-Painlev\'e Pairs


  In this paper, we introduce the notion of an Okamoto-Painlev\'e pair (S, Y)
which consists of a compact smooth complex surface S and an effective divisor Y
on S satisfying certain conditions. Though spaces of initial values of
Painlev\'e equations introduced by K. Okamoto give examples of Okamoto-Painleve
pairs, we find a new example of Okamoto-Painlev\'e pairs not listed in
\cite{Oka}. We will give the complete classification of Okamoto-Painlev\'e
pairs.

</DOC>
<DOC>
<DOCNO> 69743 </DOCNO>
Large N Quantum Time Evolution Beyond Leading Order


  For quantum theories with a classical limit (which includes the large N
limits of typical field theories), we derive a hierarchy of evolution equations
for equal time correlators which systematically incorporate corrections to the
limiting classical evolution. Explicit expressions are given for
next-to-leading order, and next-to-next-to-leading order time evolution. The
large N limit of N-component vector models, and the usual semiclassical limit
of point particle quantum mechanics are used as concrete examples. Our
formulation directly exploits the appropriate group structure which underlies
the construction of suitable coherent states and generates the classical phase
space. We discuss the growth of truncation error with time, and argue that
truncations of the large-N evolution equations are generically expected to be
useful only for times short compared to a ``decoherence'' time which scales
like N^{1/2}.

</DOC>
<DOC>
<DOCNO> 151825 </DOCNO>
Non-Relativistic Closed String Theory


  We construct a Galilean invariant non-gravitational closed string theory
whose excitations satisfy a non-relativistic dispersion relation. This theory
can be obtained by taking a consistent low energy limit of any of the
conventional string theories, including the heterotic string. We give a finite
first order worldsheet Hamiltonian for this theory and show that this string
theory has a sensible perturbative expansion, interesting high energy behavior
of scattering amplitudes and a Hagedorn transition of the thermal ensemble. The
strong coupling duals of the Galilean superstring theories are considered and
are shown to be described by an eleven-dimensional Galilean invariant theory of
light membrane fluctuations. A new class of Galilean invariant
non-gravitational theories of light-brane excitations are obtained. We exhibit
dual formulations of the strong coupling limits of these Galilean invariant
theories and show that they exhibit many of the conventional dualities of M
theory in a non-relativistic setting.

</DOC>
<DOC>
<DOCNO> 85060 </DOCNO>
Scattering of particles by neutron stars: Time-evolutions for axial


  The excitation of the axial quasi-normal modes of a relativistic star by
scattered particles is studied by evolving the time dependent perturbation
equations. This work is the first step towards the understanding of more
complicated perturbative processes, like the capture or the scattering of
particles by rotating stars. In addition, it may serve as a test for the
results of the full nonlinear evolution of binary systems.

</DOC>
<DOC>
<DOCNO> 13768 </DOCNO>
In-plane magnetic field-induced spin polarization and transition to


  Using a novel technique, we make quantitative measurements of the spin
polarization of dilute (3.4 to 6.8*10^{10} cm^{-2}) GaAs (311)A two-dimensional
holes as a function of an in-plane magnetic field. As the field is increased
the system gradually becomes spin polarized, with the degree of spin
polarization depending on the orientation of the field relative to the crystal
axes. Moreover, the behavior of the system turns from metallic to insulating
\textit{before} it is fully spin polarized. The minority-spin population at the
transition is ~8*10^{9} cm^{-2}, close to the density below which the system
makes a transition to an insulating state in the absence of a magnetic field.

</DOC>
<DOC>
<DOCNO> 122443 </DOCNO>
Hydrodynamical winds from two-temperature plasma in X-ray binaries


  Hydrodynamical winds from a spherical two-temperature plasma surrounding a
compact object are constructed. The mass-loss rate is computed as a function of
electron temperature, optical depth and luminosity of the sphere, the values of
which can be constrained by the fitting of the spectral energy distributions
for known X-ray binary systems. The sensitive dependence of the mass loss rate
with these parameters leads to the identification of two distinct regions in
the parameter space separating wind-dominated from non wind dominated systems.
A critical optical depth, tau_c, as a function of luminosity and electron
temperature, is defined which differentiates these two regions. Systems with
optical depths significantly smaller than tau_c are wind-dominated.
  The results are applied to black hole candidate X-ray binary systems in the
hard spectral state (Cyg X-1, GX 339-4 and Nova Muscae), and it is found that
the inferred optical depth (tau) is similar to tau_c suggesting that they are
wind regulated systems. On the other hand, for X-ray binary systems containing
a neutron star (e.g., Cyg X-2) tau is much larger than tau_c indicating the
absence of significant hydrodynamical winds.

</DOC>
<DOC>
<DOCNO> 9824 </DOCNO>
An Efficient and Robust Technique for Achieving Self Consistency in


  Pulay's Residual Metric Minimization (RMM) method is one of the standard
techniques for achieving self consistency in ab initio electronic structure
calculations. We describe a reformulation of Pulay's RMM which guarantees
reduction of the residual at each step. The new version avoids the use of
empirical mixing parameters, and is expected to be more robust than the
original version. We present practical tests of the new method implemented in a
standard code based on density-functional theory (DFT), pseudopotentials, and
plane-wave basis sets. The tests show improved speed in achieving self
consistency for a variety of condensed-matter systems.

</DOC>
<DOC>
<DOCNO> 119525 </DOCNO>
A Structure for Quasars


  We propose a simple unifying structure for the inner regions of quasars and
AGN. This empirically derived model links together the BALs, the narrow
UV/X-ray ionized absorbers, the BELR, and the Compton scattering/fluorescing
regions into a single structure. The model also suggests an origin for the
large-scale bi-conical outflows. Some other potential implications of this
structure are discussed.

</DOC>
<DOC>
<DOCNO> 13733 </DOCNO>
Transport through quasi-ballistic quantum wires: the role of contacts


  We model one-dimensional transport through each open channel of a quantum
wire by a Luttinger liquid with three different interaction parameters for the
leads, the contact regions and the wire, and with two barriers at the contacts.
We show that this model explains several features of recent experiments, such
as the flat conductance plateaux observed even at finite temperatures and for
different lengths, and universal conductance corrections in different channels.
We discuss the possibility of seeing resonance-like structures of a fully open
channel at very low temperatures.

</DOC>
<DOC>
<DOCNO> 116652 </DOCNO>
Time and the laws of Nature


  What is time? Why does it "flow" and why are we sure that it flows from past
towards future? Why is there such a gigantic distinction between the Past of
our world, which we believe to be fixed, and the Future, which we consider
undetermined? And this is in spite of the fact that almost all physical laws
are time-symmetric! Why does previously undetermined "Future" acquire its
steadiness as it passes the moment called "the Present"? Perhaps, these
questions are partially answered in the considerations below.

</DOC>
<DOC>
<DOCNO> 69633 </DOCNO>
Associative photoproduction of charmed particles near threshold


  We calculate the cross section and the beam asymmetry for exclusive
photoproduction of charmed particles near threshold ($\gamma+p\to \Lambda_c^+
+\bar{D^0}$), in the framework of an effective Lagrangian model. We discuss the
sensitivity of these observables to the magnetic moment of the $\Lambda_c$
baryon and of the coupling constant in the $p\Lambda_c D$ vertex. We show that
exclusive measurements allow, in principle, to determine the magnetic moments
of charmed baryons.

</DOC>
<DOC>
<DOCNO> 80917 </DOCNO>
The standard model and parity conservation


  On the basis of previous work on chiral gauged fermions on a lattice, we
discuss the lattice-regularization of the standard model by introducing two
Weyl fields interacting with quarks and leptons. These interactions form
massive bound states to gauge-invariantly decouple doublers at high energies
and these bound states dissolve into their constituents at low energies. No any
hard spontaneous symmetry breakings occur at the lattice scale \pi/a. As a
consequence, the gauge symmetries of the standard model are realized by both
massive vectorlike spectra at high energies and massless chiral spectra at low
energies. Such a scenario is consistent with the gauge-anomaly cancelation,
flavor-singlet anomaly and Witten's anomaly. These studies predict that the
parity symmetry must be restored at high energies.

</DOC>
<DOC>
<DOCNO> 10685 </DOCNO>
Profile alterations of a symmetrical light pulse coming through a


  The theory of a response of a two-energy-level system, irradiated by
symmetrical light pulses, has been developed.(Suchlike electronic system
approximates under the definite conditions a single ideal quantum well (QW) in
a strong magnetic field {\bf H}, directed perpendicularly to the QW's plane, or
in magnetic field absence.) The general formulae for the time-dependence of
non-dimensional reflection {\cal R}(t), absorption {\cal A}(t) and transmission
{\cal T}(t) of a symmetrical light pulse have been obtained. It has been shown
that the singularities of three types exist on the dependencies {\cal R}(t),
{\cal A}(t), {\cal T}(t). The oscillating time dependence of {\cal R}(t), {\cal
A}(t), {\cal T}(t) on the detuning frequency \Delta\omega=\omega_l-\omega_0
takes place. The oscillations are more easily observable when
\Delta\omega\simeq\gamma_l. The positions of the total absorption, reflection
and transparency singularities are examined when the frequency \omega_l is
detuned.

</DOC>
<DOC>
<DOCNO> 9984 </DOCNO>
Interaction-induced Bose Metal in 2D


  We show here that the regularization of the conductivity resulting from the
bosonic interactions on the `insulating' (quantum disordered) side of an
insulator-superconductor transition in 2D gives rise to a metal with a finite
conductivity, $\sigma =(2/\pi) 4 e^2/h$, as temperature tends to zero. The Bose
metal is stable to weak disorder and hence represents a concrete example of an
interaction-induced metallic phase. Phenomenological inclusion of dissipation
reinstates the anticipated insulating behaviour in the quantum-disordered
regime. Hence, we conclude that the traditionally-studied
insulator-superconductor transition, which is driven solely by quantum
fluctuations, corresponds to a superconductor-metal transition. The possible
relationship to experiments on superconducting thin films in which a
low-temperature metallic phase has been observed is discussed.

</DOC>
<DOC>
<DOCNO> 67852 </DOCNO>
First-Order Phase Transitions in an Early-Universe Environment


  In first-order phase transitions in the early universe, the bubble wall is
expected to be significantly slowed-down by its interaction with the
surrounding plasma. We examine the behaviour of the phase of the Higgs field
after two-bubble collisions, and find that phase differences equilibrate much
more quickly in slow-moving bubbles than in those which expand at the speed of
light. This could lead to a significant reduction in the initial density of
topological defects formed at a first-order phase transition.

</DOC>
<DOC>
<DOCNO> 69857 </DOCNO>
Selection rules in three-body B decay from factorization


  Extending the dynamics underlying the factorization calculation of two-body
decays, we propose simple selection rules for nonresonant three-body B decays.
We predict, for instance, that in the Dalitz plot of B^0-->D^0-bar\pi^+\pi^-,
practically no events should be found in the corner of E(\pi^+) < \Lambda_{QCD}
as compared with the corner of E(\pi^-) < \Lambda_{QCD}. We also predict that
there should be very few three-body decay events with a soft meson resonance
and two energetic mesons or meson resonances. The selection rules are quite
different from the soft pion theorem, since they apply to different kinematical
regions. For B^0 -->D^0-bar\pi^+\pi^-, the latter predicts that the decay
matrix element vanishes in the zero-four-momentum limit of \pi^+ instead of
\pi^-. Since this marked difference from the soft pion theorem is directly
related to the issue of short-distance QCD dominance in the FSI of two-body B
decays, experimental test of the selection rules will shed light on strong
interaction dynamics of B decay.

</DOC>
<DOC>
<DOCNO> 151461 </DOCNO>
A Curious Relation Between Gravity and Yang-Mills Theories


  We find that Euclidian or Minkowski gravity in d dimensions can be formally
expressed as the restriction to a slice of a supersymmetric Yang-Mills theory
in d+1 dimensions with SO(d+1), SO(d,1) or SO(d-1,2) internal symmetry. We
suggest that renormalization effects in the bulk imply a contraction of the
latter symmetry into the Poincare group ISO(d) or ISO(d-1,1).

</DOC>
<DOC>
<DOCNO> 169740 </DOCNO>
Some remarks on separability of states


  Several problems concerning separable states are clarified on the basis of
Choi's scheme and old Kadison and Tomiyama results. Moreover, we generalize
Terhal's construction of positive maps.

</DOC>
<DOC>
<DOCNO> 119460 </DOCNO>
Interstellar Gas in the NGC 4410 Galaxy Group


  We present new radio continuum, 21 cm HI, and 2.6 mm CO data for the peculiar
radio galaxy NGC 4410A and its companion NGC 4410B, and compare with available
optical and X-ray maps. Our radio continuum maps show an asymmetric
double-lobedstructure, with a high surface brightness lobe extending 3.6 arcmin
(~100 kpc) to the southeast and a 6.2 arcmin (~180 kpc) low surface brightness
feature in the northwest. Molecular gas is abundant in NGC 4410A, with M(H2) ~
4 X 10^9 M(sun) (using the standard Galactic conversion factor), but is
undetected in NGC 4410B. HI is less abundant, with M(HI) ~ 10^9 M(sun) for the
pair. Our HI map shows a 3 X 10^8 M(sun) HI tail extending 1.7 arcmin (50 kpc)
to the southeast of the pair, coincident with a faint optical tail and
partially overlapping with the southeastern radio lobe. The HI tail is
anti-coincident with a 2' (56 kpc) long X-ray structure aligned with a stellar
bridge that connects the pair to a third galaxy. If this X-ray emission is
associated with the group, there is 3 - 8 X 10^8 M(sun) of hot gas in this
feature: either intracluster gas or shocked gas associated with the bridge. Our
detection of abundant interstellar gas in this pair suggests that the
distortions in this lobe map have been caused by the interstellar medium in
this system. The interaction of the two galaxies and the subsequent motion of
the interstellar medium in the system relative to the jet may have produced
sufficient ram pressure to bend the radio jet. An alternative hypothesis is
that the jet was distorted by ram pressure due to an intracluster medium,
although the small radial velocity of NGC 4410A relative to the group and the
lack of diffuse X-ray emission in the group makes this less likely unless the
group is not virialized or is in the process of merging with another group.

</DOC>
<DOC>
<DOCNO> 101109 </DOCNO>
D-modules on Smooth Toric Varieties


  Let X be a smooth toric variety. David Cox introduced the homogeneous
coordinate ring S of X and its irrelevant ideal B. Extending well-known results
on projective space, Cox established the following: (1) the category of
quasi-coherent sheaves on X is equivalent to the category of graded S-modules
modulo B-torsion, (2) the variety X is a geometric quotient of Spec(S) V(B) by
a suitable torus action. We provide the D-module version of these results. More
specifically, let A denote the ring of differential operators on Spec(S). We
show that the category of D-modules on X is equivalent to a subcategory of
graded A-modules modulo B-torsion. Additionally, we prove that the
characteristic variety of a D-module is a geometric quotient of an open subset
of the characteristic variety of the associated A-module and that holonomic
D-modules correspond to holonomic A-modules.

</DOC>
<DOC>
<DOCNO> 72187 </DOCNO>
Azimuthal asymmetries at HERA: theoretical aspects


  We comment on theoretical aspects of the measurement of azimuthal asymmetries
in semi-inclusive charged particle production, made recently by the ZEUS
Collaboration at HERA. By taking the ratio of the two measured asymmetries, we
find good agreement between the perturbative QCD prediction and the
experimental data. To separate the perturbative and nonperturbative
contributions to the asymmetries, we suggest that the azimuthal asymmetries of
the transverse energy flow be measured as a function of a variable $q_T$
related to the pseudorapidity of the energy flow.

</DOC>
<DOC>
<DOCNO> 9074 </DOCNO>
Collective oscillations of two colliding Bose-Einstein condensates


  Two 87Rb condensates (F=2, m_f=2 and m_f=1) are produced in highly displaced
harmonic traps and the collective dynamical behaviour is investigated. The
mutual interaction between the two condensates is evidenced in the
center-of-mass oscillations as a frequency shift of 6.4(3)%. Calculations based
on a mean-field theory well describe the observed effects of periodical
collisions both on the center-of-mass motion and on the shape oscillations.

</DOC>
<DOC>
<DOCNO> 13930 </DOCNO>
Elementary excitation families and their frequency ordering in


  We present a systematic classification of the elementary excitations of
Bose-Einstein condensates in cylindrical traps in terms of their shapes. The
classification generalizes the concept of families of excitations first
identified by Hutchinson and Zaremba (1998) Phys. Rev. A 57 1280 by introducing
a second classification number that allows all possible modes to be assigned to
a family. We relate the energy ordering of the modes to their family
classification, and provide a simple model which explains the relationship.

</DOC>
<DOC>
<DOCNO> 9450 </DOCNO>
Can a frustrated spin-cluster model describe the low-temperature physics


  Recent experimental evidence suggest the existence of three distinct
V-valence states (V^{+4}, V^{+4.5} and V^{+5}) in the low-temperature phase of
NaV_2O_5 in apparent discrepancy with the observed spin-gap. We investigate a
novel spin cluster model, consisting of weakly coupled, frustrated four-spin
clusters aligned along the crystallographic b-axis that was recently proposed
to reconcile these experimental observations. We have studied the phase diagram
and the magnon dispersion relation of this model using DMRG, exact
diagonalization and a novel cluster-operator theory. We find a spin-gap for all
parameter values and two distinct phases, a cluster phase and a Haldane phase.
We evaluate the size of the gap and the magnon dispersion and find no parameter
regime which would reproduce the experimental results. We conclude that this
model is inappropriate for the low-temperature regime of NaV_2O_5.

</DOC>
<DOC>
<DOCNO> 116719 </DOCNO>
Spectroscopic electric-field measurement in laser-excited plasmas


  The electric field in mm-sized clouds of cold Rb^+-ions is measured using the
Stark effect of Rydberg atoms embedded in the ion clouds. The ion clouds are
produced by UV photoionization of laser-cooled rubidium atoms in a
magneto-optic trap. In very dense ion clouds, the Rydberg atom excitation
spectra reflect the presence of a neutral plasma core and a positively charged
ion shell.

</DOC>
<DOC>
<DOCNO> 83417 </DOCNO>
Generalization of a 3-D resonator model for the simulation of spherical


  A rectangular enclosure has such an even distribution of resonances that it
can be accurately and efficiently modelled using a feedback delay network.
Conversely, a non rectangular shape such as a sphere has a distribution of
resonances that challenges the construction of an efficient model. This work
proposes an extension of the already known feedback delay network structure to
model the resonant properties of a sphere. A specific frequency distribution of
resonances can be approximated, up to a certain frequency, by inserting an
allpass filter of moderate order after each delay line of a feedback delay
network. The structure used for rectangular boxes is therefore augmented with a
set of allpass filters allowing parametric control over the enclosure size and
the boundary properties. This work was motivated by informal listening tests
which have shown that it is possible to identify a basic shape just from the
distribution of its audible resonances.

</DOC>
<DOC>
<DOCNO> 151426 </DOCNO>
On the Running Gauge Coupling Constant in the Exact Renormalization


  In this paper, we investigate the beta-function of the gauge coupling
constant ($e$) of the gauged four-fermi theory in the Exact Renormalization
Group (ERG) framework. It seems that the presence of the four-fermi interaction
strongly affects to the naive RG running of the gauge coupling constant. We
show that this strong correction has no physical meaning since the vertex $\app
A\SR\psi$ involves the contribution from a mixing as well as a pure gauge
interaction due to the (anomalous) mixing among the photon and the vector
composite field. By introducing the auxiliary field for the vector composite
field, the situation turns to be rather clear. We adopt the counterterm to
cancel the gauge non-invariant correction, and decompose the pure gauge
interaction from the contribution of the mixing. We find the beta-function of
the gauge coupling constant in the large $N$ limit.

</DOC>
<DOC>
<DOCNO> 10443 </DOCNO>
Superradiant light scattering and grating formation in cold atomic


  A semi-classical theory of coherent light scattering from an elongated sample
of cold atoms exposed to an off-resonant laser beam is presented. The model,
which is a direct extension of that of the collective atomic recoil laser
(CARL), describes the emission of two superradiant pulses along the sample's
major axis simultaneous with the formation of a bidimensional atomic grating
inside the sample. It provides a simple physical picture of the recent
observation of collective light scattering from a Bose-Einstein condensate [S.
Inouye et al., Science N.285, p. 571 (1999)]. In addition, the model provides
an analytical description of the temporal evolution of the scattered light
intensity which shows good quantitative agreement with the experimental results
of Inouye et al.

</DOC>
<DOC>
<DOCNO> 12477 </DOCNO>
Active Fusion and Fission Processes on a Fluid Membrane


  We investigate the steady states and dynamical instabilities resulting from
``particles'' depositing on (fusion) and pinching off (fission) a fluid
membrane. These particles could be either small lipid vesicles or isolated
proteins. In the stable case, such fusion/fission events suppress long
wavelength fluctuations of the membrane. In the unstable case, the membrane
shoots out long tubular structures reminiscent of endosomal compartments or
folded structures as in internal membranes like the endoplasmic reticulum or
Golgi. We argue that these fusion/fission events should be strongly affected by
tension.

</DOC>
<DOC>
<DOCNO> 116842 </DOCNO>
The RF source of the 60-MeV Linac for the KEK/JAERI Joint Project


  The construction of the 60-MeV proton linac has started as a low-energy front
of the KEK/JAERI Joint Project for a high-intensity proton accelerator facility
at KEK. The accelerating frequency is 324 MHz. Five UHF klystrons are used as
an rf source; their ratings have a maximum power of 3 MW, a beam pulse width of
a 700 micro-sec (an rf pulse width is 650 micro-sec) and a repetition rate of
50 pps. We have manufactured a proto-type rf source (a power-supply system with
a modulating-anode pulse modulator and prototype klystrons). In this paper, the
specifications and developments of the rf source, including the WR-2300
waveguide system, are summarized. During the manufacturing process, strong
oscillations due to back-going electrons from the collector were observed. This
phenomenon was analyzed both experimentally and theoretically. We have tested
up to an output power of nearly 3 MW, and succeeded to test the DTL hot-model
structure.

</DOC>
<DOC>
<DOCNO> 10776 </DOCNO>
Quantum Poincare' recurrences in microwave ionization of Rydberg atoms


  We study the time dependence of the ionization probability of Rydberg atoms
driven by a microwave field. The quantum survival probability follows the
classical one up to the Heisenberg time and then decays inversely proportional
to time, due to tunneling and localization effects. We provide parameter values
which should allow one to observe such decay in laboratory experiments.
Relations to the $1/f$ noise are also discussed.

</DOC>
<DOC>
<DOCNO> 120620 </DOCNO>
A Circular Statistical Method for Extracting Rotation Measures


  We propose a new method for the extraction of Rotation Measure from spectral
polarization data. The method is based on maximum likelihood analysis and takes
into account the circular nature of the polarization data. The method is
unbiased and statistically more efficient than the standard $\chi^2$ procedure.
We also find that the method is computationally much faster than the standard
$\chi^2$ procedure if the number of data points are very large.

</DOC>
<DOC>
<DOCNO> 84901 </DOCNO>
Defining Entropy Bounds


  Bekenstein's conjectured entropy bound for a system of linear size R and
energy E, S < 2 pi E R, has counterexamples for many of the ways in which the
``system,'' R, E, and S may be defined. Here new ways are proposed to define
these quantities for arbitrary nongravitational quantum field theories in flat
spacetime, such as defining R as the smallest radius outside of which only
vacuum expectation values occur. Difficulties of extending these definitions to
gravitational quantum theories are noted.

</DOC>
<DOC>
<DOCNO> 68141 </DOCNO>
Six-quark decays of off-shell WW pairs via parton-level QCD in


  We study the decays into six quarks of off-shell pairs of W bosons produced
in electron-positron annihilations, through the O(as^2) order in the strong
coupling constant. We give explicit helicity amplitude formulae. We present
numerical results in the context of phenomenological analyses of relevance at
LEP2 and future Linear Colliders: such as MW determinations, New Physics and
Higgs searches.

</DOC>
<DOC>
<DOCNO> 102177 </DOCNO>
Verma-type Modules for Quantum Affine Lie Algebras


  Let g be an untwisted affine Kac-Moody algebra and M_J(lambda) a Verma-type
module for g with J-highest integral weight lambda. We construct quantum
Verma-type modules M_J^q(lambda) over the quantum group U_q(g), investigate
their properties and show that M_J^q(lambda) is a true quantum deformation of
M_J(\l) in the sense that the weight structure is preserved under the
deformation. We also analyze the submodule structure of quantum Verma-type
modules.

</DOC>
<DOC>
<DOCNO> 67892 </DOCNO>
DIRAC Experiment and Test of Low-Energy QCD


  The low-energy QCD predictions to be tested by the DIRAC experiment are
revised. The experimental method, the setup characteristics and capabilities,
along with first experimental results are reported. Preliminary analysis shows
good detector performance: alignment error via $\Lambda$ mass measurement
$m_\Lambda = 1115.6 MeV/c^2$ with $\sigma = 0.92 MeV/c^2$, $p \pi^-$ relative
momentum resolution $\sigma_Q \approx 2.7 MeV/c$, and evidence for $\pi^+
\pi^-$ low momentum Coulomb correlation.

</DOC>
<DOC>
<DOCNO> 84983 </DOCNO>
Gravitational Collapse of Cylindrical Shells Made of Counter-Rotating


  The general formulas of a non-rotating dynamic thin shell that connects two
arbitrary cylindrical regions are given using Israel's method. As an
application of them, the dynamics of a thin shell made of counter-rotating dust
particles, which emits both gravitational waves and massless particles when it
is expanding or collapsing, is studied. It is found that when the models
represent a collapsing shell, in some cases the angular momentum of the dust
particles is strong enough to halt the collapse, so that a spacetime
singularity is prevented from forming, while in other cases it is not, and a
line-like spacetime singularity is finally formed on the symmetry axis.

</DOC>
<DOC>
<DOCNO> 174481 </DOCNO>
Parity violation in reactions with B- and Li- nuclei using polarized


  Parity violation in the $(n,\alpha)$ reactions on $^6$Li and $^{10}$B nuclei
and in the $\gamma$-transition between two lowest levels of $^7$Li nucleus is
discussed. It appears that the effects (neutral currents contribution in
particular) are measurable due to the large values of the neutron cross
sections. This holds promise for the theoretical extraction of the constants of
the weak NN potential because of the relative simplicity of the investigated
systems.

</DOC>
<DOC>
<DOCNO> 178923 </DOCNO>
Collective flow and multiparticle azimuthal correlations


  The measurement of azimuthal distributions in nucleus-nucleus collisions
relies upon the assumption that azimuthal correlations between particles result
solely from their correlation with the reaction plane (i.e. flow). We show that
at SPS energies, the ansatz is no longer valid, and two-particle correlations
due to momentum conservation, final state interactions or resonance decays
become of the same order as those arising from flow. This leads us to introduce
new methods to analyse collective flow, based on a cumulant expansion, which
enable to extract smaller values than those accessible to the standard
analysis.

</DOC>
<DOC>
<DOCNO> 10954 </DOCNO>
Metastability and low lying spectra in reversible Markov chains


  We study a large class of reversible Markov chains with discrete state space
and transition matrix $P_N$. We define the notion of a set of {\it metastable
points} as a subset of the state space $\G_N$ such that (i) this set is reached
from any point $x\in \G_N$ without return to x with probability at least $b_N$,
while (ii) for any two point x,y in the metastable set, the probability
$T^{-1}_{x,y}$ to reach y from x without return to x is smaller than
$a_N^{-1}\ll b_N$. Under some additional non-degeneracy assumption, we show
that in such a situation: \item{(i)} To each metastable point corresponds a
metastable state, whose mean exit time can be computed precisely. \item{(ii)}
To each metastable point corresponds one simple eigenvalue of $1-P_N$ which is
essentially equal to the inverse mean exit time from this state. The
corresponding eigenfunctions are close to the indicator function of the support
of the metastable state. Moreover, these results imply very sharp uniform
control of the deviation of the probability distribution of metastable exit
times from the exponential distribution.

</DOC>
<DOC>
<DOCNO> 8780 </DOCNO>
The Statistical Physics of Regular Low-Density Parity-Check


  A variation of Gallager error-correcting codes is investigated using
statistical mechanics. In codes of this type, a given message is encoded into a
codeword which comprises Boolean sums of message bits selected by two randomly
constructed sparse matrices. The similarity of these codes to Ising spin
systems with random interaction makes it possible to assess their typical
performance by analytical methods developed in the study of disordered systems.
The typical case solutions obtained via the replica method are consistent with
those obtained in simulations using belief propagation (BP) decoding. We
discuss the practical implications of the results obtained and suggest a
computationally efficient construction for one of the more practical
configurations.

</DOC>
<DOC>
<DOCNO> 151532 </DOCNO>
The N U D problem


  The hybrid spectral problem where the field satisfies Dirichlet conditions
(D) on part of the boundary of the relevant domain and Neumann (N) on the
remainder is discussed in simple terms. A conjecture for the C_1 coefficient is
presented and the conformal determinant on a 2-disc, where the D and N regions
are semi-circles, is derived. Comments on higher coefficients are made.

</DOC>
<DOC>
<DOCNO> 85390 </DOCNO>
Gravitational waves emitted by solar-type stars excited by orbiting


  The possibility of exciting the g-modes of a solar-type star as a consequence
of the gravitational interaction with a close companion (a planet or a brown
dwarf) is studied by a perturbative approach. The amplitude of the emitted
gravitational wave is computed and compared with the quadrupole emission of the
system, showing that in some cases it can be considerably larger. The effects
of radiation reaction are considered to evaluate the timescale of the emission
process, and a Roche lobe analysis is used to establish the region where the
companion can orbit without being disrupted by tidal interactions with the
star.

</DOC>
<DOC>
<DOCNO> 101034 </DOCNO>
The Complex Hyperbolic Geometry of the Moduli Space of Cubic Surfaces


  Recall that the moduli space of smooth (that is, stable) cubic curves is
isomorphic to the quotient of the upper half plane by the group of fractional
linear transformations with integer coefficients. We establish a similar result
for stable cubic surfaces: the moduli space is biholomorphic to a quotient of
the compex 4-ball by an explict arithmetic group generated by complex
reflections. This identification gives interesting structural information on
the moduli space and allows one to locate the points in complex hyperbolic
4-space corresponding to cubic surfaces with symmetry, e.g., the Fermat cubic
surface.
  Related results, not quite as extensive, were announced in alg-geom/9709016.

</DOC>
<DOC>
<DOCNO> 100367 </DOCNO>
Functions of Baire class one


  Let $K$ be a compact metric space. A real-valued function on $K$ is said to
be of Baire class one (Baire-1) if it is the pointwise limit of a sequence of
continuous functions. In this paper, we study two well known ordinal indices of
Baire-1 functions, the oscillation index $\beta$ and the convergence index
$\gamma$. It is shown that these two indices are fully compatible in the
following sense : a Baire-1 function $f$ satisfies $\beta(f) \leq
\omega^{\xi_1} \cdot \omega^{\xi_2}$ for some countable ordinals $\xi_1$ and
$\xi_2$ if and only if there exists a sequence of Baire-1 functions $(f_n)$
converging to $f$ pointwise such that $\sup_n\beta(f_n) \leq \omega^{\xi_1}$
and $\gamma((f_n)) \leq \omega^{\xi_2}$. We also obtain an extension result for
Baire-1 functions analogous to the Tietze Extension Theorem. Finally, it is
shown that if $\beta(f) \leq \omega^{\xi_1}$ and $\beta(g) \leq
\omega^{\xi_2},$ then $\beta(fg) \leq \omega^{\xi},$ where
$\xi=\max\{\xi_1+\xi_2, \xi_2+\xi_1}\}.$ These results do not assume the
boundedness of the functions involved.

</DOC>
<DOC>
<DOCNO> 151374 </DOCNO>
Quantum spin chain with "soliton non-preserving" boundary conditions


  We consider the case of an integrable quantum spin chain with "soliton
non-peserving" boundary conditions. This is the first time that such boundary
conditions have been considered in the spin chain framework. We construct the
transfer matrix of the model, we study its symmetry and we find explicit
expressions for its eigenvalues. Moreover, we derive a new set of Bethe ansatz
equations by means of the analytical Bethe ansatz method.

</DOC>
<DOC>
<DOCNO> 11987 </DOCNO>
Effects of dissipation on quantum phase transitions


  We discuss the effect of dissipation on quantum phase transitions. In
particular we concentrate on the Superconductor to Insulator and Quantum-Hall
to Insulator transitions. By invoking a phenomenological parameter $\alpha$ to
describe the coupling of the system to a continuum of degrees of freedom
representing the dissipative bath, we obtain new phase diagrams for the quantum
Hall and superconductor-insulator problems. Our main result is that, in
two-dimensions, the metallic phases observed in finite magnetic fields
(possibly also strictly zero field) are adiabatically deformable from one to
the other. This is plausible, as there is no broken symmetry which
differentiates them.

</DOC>
<DOC>
<DOCNO> 69103 </DOCNO>
Are lepton flavor mixings in the democratic mass matrix stable against


  We investigate whether the lepton flavor mixing angles in the so-called
democratic type of mass matrix are stable against quantum corrections or not in
the minimal supersymmetric standard model with dimension five operator which
induces neutrino mass matrix. By taking simple breaking patterns of $S_3{}_L
\times S_3{}_R$ or $O(3)_L \times O(3)_R$ flavor symmetries and the scale where
democratic textures are induced as $O(10^{13})$ GeV, we find that the stability
of the lepton flavor mixing angles in the democratic type of mass matrix
against quantum corrections depends on the solar neutrino solutions. The
maximal flavor mixing of the vacuum oscillation solution is spoiled by the
quantum corrections in the experimental allowed region of $\tan \beta$. The
large angle MSW solution is spoiled by the quantum corrections in the region of
$\tan \beta > 10$. The condition of $\tan \beta \leq 10$ is needed in order to
obtain the suitable mass squared difference of the small angle MSW solution.
These strong constraints must be regarded for the model building of the
democratic type of mass matrix

</DOC>
<DOC>
<DOCNO> 10151 </DOCNO>
Nanometer-scale capacitors


  Molecular dynamics computer simulations which employ the embedded-atom
potential show that nanowires of gold exist as multishelled structures. We
simulate double-walled gold nanowires and calculate the capacitance of a finite
nanometer-size cylindrical capacitor. For the sizes for which multishelled
nanowires appear in simulations we find the capacitances below one attofarad.

</DOC>
<DOC>
<DOCNO> 40496 </DOCNO>
Jet energy scale setting with "Gamma+Jet" events at LHC energies.


  The possibilities of the background events suppression, based on the QCD
subprocesses of qg-, gg-, qq- scattering with big cross sections, to the signal
\gpj events are studied. Basing on the introduced selection criteria, the
background suppression factors and signal events selection efficiencies and the
number of the events, that can be collected at LHC with low luminosity
L=10^{33}cm^2 s^{-1} during one month of continuous work, are determined.

</DOC>
<DOC>
<DOCNO> 72216 </DOCNO>
Four-Flux and Warped Heterotic M-Theory Compactifications


  In the framework of heterotic M-theory compactified on a Calabi-Yau threefold
'times' an interval, the relation between geometry and four-flux is derived
{\it beyond first order}. Besides the case with general flux which cannot be
described by a warped geometry one is naturally led to consider two special
types of four-flux in detail. One choice shows how the M-theory relation
between warped geometry and flux reproduces the analogous one of the weakly
coupled heterotic string with torsion. The other one leads to a {\it quadratic}
dependence of the Calabi-Yau volume with respect to the orbifold direction
which avoids the problem with negative volume of the first order approximation.
As in the first order analysis we still find that Newton's Constant is bounded
from below at just the phenomenologically relevant value. However, the bound
does not require an {\it ad hoc} truncation of the orbifold-size any longer.
Finally we demonstrate explicitly that to leading order in $\kappa^{2/3}$ no
Cosmological Constant is induced in the four-dimensional low-energy action.
This is in accord with what one can expect from supersymmetry.

</DOC>
<DOC>
<DOCNO> 68733 </DOCNO>
Simplification of Flavour Combinatorics in the Evaluation of Hadronic


  A serious computational problem in the evaluation of hadronic collision
processes is connected with the large number of partonic subprocesses included
in the calculation. These are from the quark and gluon content of the initial
hadrons, and from CKM quark mixing. For example, there are 180 subprocesses
which contribute to the $W$+2jets process, and 292 subprocesses in $W$+3jets
production at the LHC, even when quarks from only the first two generations are
taken into account.
  We propose a simple modification of the rules for evaluation of cross
sections and distributions, which avoids multiplication of channels from the
mixture of quark states. The method is based on a unitary rotation of down
quarks, thus, transporting the mixing matrix elements from vertices of Feynman
diagrams to the parton distribution functions (PDF). As a result, one can
calculate cross sections with significantly fewer subprocesses. For the example
mentioned above, with the new rules, one need evaluate only 21 and 33
subprocesses respectively. The matrix elements of the subprocesses are
calculated without quark mixing but with a modified PDF convolution which
depends on the quark mixing angle, and on the topologies of gauge invariant
classes of diagrams. The proposed method has been incorporated into the CompHEP
program and checked with various examples.

</DOC>
<DOC>
<DOCNO> 70057 </DOCNO>
Quantum Fiel Theoretic Treatment of the Non-Forward Compton Amplitude in


  A quantum field theoretic treatment of the leading light-cone part of the
virtual Compton amplitude is presented. The twist-decomposition of the
operators is performed by a group-theoretic procedure respecting the Lorentz
group O(3,1). The twist-2 contributions to the Compton amplitude are calculated
and it is shown that the electromagnetic current is conserved for these terms.
Relations between the amplitude functions associated to the symmetric and
asymmetric part of the Compton amplitude are derived. These relations
generalize the Callan-Gross and Wandzura-Wilczek relations of forward
scattering for the non-forward Compton amplitude.

</DOC>
<DOC>
<DOCNO> 178819 </DOCNO>
Quasi-SU(3) truncation scheme for even-even sd-shell nuclei


  The Quasi-SU(3) symmetry was uncovered in full pf and sdg shell-model
calculations for both even-even and odd-even nuclei. It manifests itself
through a dominance of single-particle and quadrupole-quadrupole terms in the
Hamiltonian used to describe well-deformed nuclei. A practical consequence of
the quasi-SU(3) symmetry is an efficient basis truncation scheme. In a recent
work was shown that when this type of Hamiltonian is diagonalized in an SU(3)
basis, only a few irreducible represntations (irreps) of SU(3) are needed to
describe the Yrast band, the leading S = 0 irrep augmented with the leading S =
1 irreps in the proton and neutron subspaces. In the present article the
quasi-SU(3) truncation scheme is used, in conjunction with a "realistic but
schematic" Hamiltonian that includes the most important multipole terms, to
describe the energy spectra and B(E2) transition strengths of 20-Ne, 22-Ne,
24-Mg and 28-Si. The effect of the size of the Hilbert space on both sets of
observables is discussed, as well as the structure of the Yrast band and the
importance of the various terms in the Hamiltonian.

</DOC>
<DOC>
<DOCNO> 119229 </DOCNO>
ENEAR Redshift-Distance Survey: Cosmological Constraints


  We present an analysis of the ENEAR sample of peculiar velocities of
elliptical galaxies, obtained with D_n-\sigma distances. We use the velocity
correlation function to analyze the statistics of the field-object's
velocities, while the analysis of the cluster data is based on the estimate of
their rms peculiar velocity, Vrms. The statistics of the model velocity field
is parameterized by the amplitude, \eta_8=\sigma_8 \Omega_m^{0.6}, and by the
shape parameter, \Gamma. From the velocity correlation statistics we obtain
\eta_8=0.51{-0.09}{+0.24} for \Gamma=0.25 at the 2\sigma level. Even though
less constraining, a consistent result is obtained by comparing the measured
Vrms of clusters to linear theory predictions. For \Gamma=0.25 we find
\eta_8=0.63{-0.19}{+0.22}$ at 1\sigma. Overall, our results point toward a
statistical concordance of the cosmic flows traced by spirals and early-type
galaxies, with galaxy distances estimated using TF and D_n-\sigma distance
indicators, respectively.

</DOC>
<DOC>
<DOCNO> 12826 </DOCNO>
One dimensional drift-diffusion between two absorbing boundaries:


  Motivated by a novel method for granular segregation, we analyze the one
dimensional drift-diffusion between two absorbing boundaries. The time
evolution of the probability distribution and the rate of absorption are given
by explicit formulae, the splitting probability and the mean first passage time
are also calculated. Applying the results we find optimal parameters for
segregating binary granular mixtures.

</DOC>
<DOC>
<DOCNO> 119656 </DOCNO>
The Star Formation History of the Local Group


  The star formation histories of Local Group galaxies are summarized. The
three large spirals are discussed individually, whereas the discussion of the
Local Group dwarfs concentrates on differences and commonalities. While Local
Group galaxies exhibit an amazing diversity in their star formation and
enrichment histories even within the same morphological type, they share a
number of common global properties. Major determining factors for their
evolution are galaxy mass and environmental effects such as ram pressure and
tidal stripping. It seems likely that low-mass dwarf irregular galaxies evolve
into dwarf spheroidals.

</DOC>
<DOC>
<DOCNO> 68007 </DOCNO>
Asymptotic Dynamics in Quantum Field Theory - When does the coupling


  We discuss the approach to asymptotic dynamics due to Kulish and Faddeev. We
show that there are problems in applying this method to theories with four
point interactions. The source of the difficulties is identified and a more
general method is constructed. This is then applied to various theories
including some where the coupling does switch off at large times and some where
it does not.

</DOC>
<DOC>
<DOCNO> 13377 </DOCNO>
Depinning of a dislocation: the influence of long-range interactions


  The theory of the depinning transition of elastic manifolds in random media
provides a framework for the statistical dynamics of dislocation systems at
yield. We consider the case of a single flexible dislocation gliding through a
random stress field generated by a distribution of immobile dislocations
threading through its glide plane. The immobile dislocations are arranged in a
"restrictedly random" manner and provide an effective stress field whose
statistical properties can be calculated explicitly. We write an equation of
motion for the dislocation and compute the associated depinning force, which
may be identified with the yield stress. Numerical simulations of a discretized
version of the equation confirm these results and allow us to investigate the
critical dynamics of the pinning-depinning transition.

</DOC>
<DOC>
<DOCNO> 80940 </DOCNO>
Chemical potential response of meson masses at finite temperature


  We study the response of meson masses to the chemical potential
($\partial{m}/\partial{\mu}$) at high temperature and at zero chemical
potential on $N_f=2$ lattice with staggered fermions. Preliminary results for
the meson composed of different quarks show that
$\partial{m}/\partial{\mu}|_{\mu=0}$ is negative in the confinement phase and
positive in the deconfinement phase.

</DOC>
<DOC>
<DOCNO> 178710 </DOCNO>
Observable measures of critical behavior in high-energy nuclear


  Critical behaviors of quark-hadron phase transition in high-energy heavy-ion
collisions are investigated with the aim of identifying hadronic observables.
The surface of the plasma cylinder is mapped onto a 2D lattice. The Ising model
is used to simulate configurations corresponding to cross-over transitions in
accordance to the findings of QCD lattice gauge theory. Hadrons are formed in
clusters of all sizes. Various measures are examined to quantify the
fluctuations of the cluster sizes and of the voids among the clusters. The
canonical power-law behaviors near the critical temperature are found for
appropriately chosen measures. Since the temperature is not directly
observable, attention is given to the problem of finding observable measures.
It is demonstrated that for the measures considered the dependence on the
final-state randomization is weak. Thus the critical behavior of the measures
proposed is likely to survive the scattering effect of the hadron gas in the
final state.

</DOC>
<DOC>
<DOCNO> 70489 </DOCNO>
Asymmetry in Charmed Particles Production in $\Sigma^{-}$ beam


  We present the calculation of the inclusive $x_F$-distributions of charmed
hadrons, produced in high-energy $\Sigma^-$-beam. The calculation is based on
the modified mechanism of charmed quarks fragmentation as well as on the
mechanism of $c$-quark recombination with the valence quarks from initial
hadrons. We predict the additional asymmetry in the production of charmed
hadrons due to the different distributions of the valence s and d quarks in
$\Sigma^-$-beam.

</DOC>
<DOC>
<DOCNO> 151201 </DOCNO>
Holographic conformal anomaly with bulk scalars potential from d3 and d5


  d3 and d5 maximally SUSY gauged supergravity is considered in the
parametrization (flow) of full scalar coset where the kinetic term for scalars
takes the standard field theory form and the bulk potential is an arbitrary one
subject to consistent parametrization. From such SG duals we calculate d2 and
d4 holographic conformal anomaly which depends on bulk scalars potential.
AdS/CFT correspondence suggests that such SG side conformal anomaly should be
identified with (non-perturbative) QFT conformal anomaly (taking account of
radiative corrections) for the theory living on the boundary of AdS space. In
the limit of constant bulk potential and single scalar, d4 result reproduces
the known exact conformal anomaly corresponding to maximally SUSY super
Yang-Mills theory coupled to ${\cal N}=4$ conformal supergravity.

</DOC>
<DOC>
<DOCNO> 123015 </DOCNO>
The DIRECT Project: Catalogs of Stellar Objects in Nearby Galaxies. I.


  The DIRECT project aims to determine direct distances to two important
galaxies in the cosmological distance ladder -- M31 and M33 -- using detached
eclipsing binaries (DEBs) and Cepheids. The search for these variables requires
time-series photometry of large areas of the target galaxies and yields
magnitudes and positions for tens of thousands of stellar objects, which may be
of use to the astronomical community at large.
  During the first phase of the project, between September 1996 and October
1997, we were awarded 95 nights on the F. L. Whipple Observatory 1.2 m
telescope and 36 nights on the Michigan-Dartmouth-MIT 1.3 m telescope to search
for DEBs and Cepheids in the M31 and M33 galaxies. This paper, the first in our
series of stellar catalogs, lists the positions, three-color photometry, and
variability indices of 57,581 stars with 14.4 < V < 23.6 in the central part of
M33. The catalog is available from our FTP site at
ftp://cfa-ftp.harvard.edu/pub/kstanek/DIRECT/star_catalog/M33ABC/

</DOC>
<DOC>
<DOCNO> 119268 </DOCNO>
Multiwavelength Examination of the COS-B Field 2CG 075+00 Yields a


  We present a high-energy study of the intriguing COS-B gamma-ray field, 2CG
075+00, in order to search for possible counterparts. New EGRET data show that
the COS-B emission probably corresponds to two localized gamma-ray sources, 3EG
J2016+3657 and 3EG J2021+3716. Spectral fits to these EGRET sources, assuming a
power-law model, yield photon indices of ~ 2 for each object. We examine
archival ROSAT and ASCA X-ray data which overlap both EGRET error boxes, and
find several point sources in the region to a flux limit of approximately 6.5 x
10^{-13} erg cm^{-2} s^{-1}. We conclude that the most probable candidate for
3EG J2016+3657 is the compact, variable, flat-spectrum radio and millimeter
source B2013+370 (G74.87+1.22) which has blazar-like properties. The other
source, 3EG J2021+3716, remains unidentified.

</DOC>
<DOC>
<DOCNO> 118667 </DOCNO>
Significant effects of weak gravitational lensing on determinations of


  Significant adjustments to the values of the cosmological parameters
estimated from high-redshift Type Ia Supernov\ae data are reported, almost an
order of magnitude greater than previously found. They arise from the effects
of weak gravitational lensing on observations of high-redshift sources. The
lensing statistics used have been obtained from computations of the
three-dimensional shear in a range of cosmological N-body simulations, from
which it is estimated that cosmologies with an underlying deceleration
parameter q_0 = -0.51 +0.03/-0.24 may be interpreted as having q_0 = -0.55
(appropriate to the currently popular cosmology with density parameter
$\Omega_M = 0.3$ and vacuum energy density parameter $\Omega_{\Lambda} = 0.7$).
In addition, the standard deviation expected from weak lensing for the peak
magnitudes of Type Ia Supernov\ae at redshifts of 1 is expected to be
approximately 0.078 magnitudes, and 0.185 magnitudes at redshift 2. This latter
value is greater than the accepted intrinsic dispersion of 0.17 magnitudes.
Consequently, the effects of weak lensing in observations of high-redshift
sources must be taken properly into account.

</DOC>
<DOC>
<DOCNO> 119333 </DOCNO>
Cirrus spectra of low surface brightness regions


  We have studied the galactic cirrus in low surface brightness regions using
ISOPHOT raster maps at 90, 150 and 180um. Observations are used to determine
dust emission spectra and dust temperatures. The data extend to longer
wavelengths than IRAS observation. Compared with DIRBE data the resolution and
the sensitivity are better and this makes it possible to study faint cirrus
emission in individual fields.
  We will discuss the calibration of the observations and present results of a
comparison between ISOPHOT and DIRBE surface brightness values. The
correspondence was found to be better than 30%. At 90um the ISOPHOT surface
brightnesses tend to be slightly higher than the DIRBE values while at longer
wavelength the situation is reversed.
  Surface brightness variations caused by cirrus fluctuations make it possible
to determine the spectrum of the dust emission. Cirrus spectra were obtained
for six fields with surface brightnesses in the range 1-2 MJy/sr after the
Zodiacal light and the contribution of extragalactic sources have been
subtracted. Assuming f^2 emissivity law the dust temperatures are in the range
18-20 K. Temperature variations can be seen even within individual fields.
These values are higher than values from DIRBE but this can be explained by
differences in the calibration.

</DOC>
<DOC>
<DOCNO> 11066 </DOCNO>
Paramagnetic Meissner Effect in Multiply-Connected Superconductors


  We have measured a paramagnetic Meissner effect in Nb-Al2O3-Nb Josephson
junction arrays using a scanning SQUID microscope. The arrays exhibit
diamagnetism for some cooling fields and paramagnetism for other cooling
fields. The measured mean magnetization is always less than 0.3 flux quantum
(in terms of flux per unit cell of the array) for the range of cooling fields
investigated. We demonstrate that a new model of magnetic screening, valid for
multiply-connected superconductors, reproduces all of the essential features of
paramagnetism that we observe and that no exotic mechanism, such as d-wave
superconductivity, is needed for paramagnetism.

</DOC>
<DOC>
<DOCNO> 99837 </DOCNO>
Gau{\ss} Cubature for the Surface of the Unit Sphere


  Gau{\ss} cubature (multidimensional numerical integration) rules are the
natural generalisation of the 1D Gau{\ss} rules. They are optimal in the sense
that they exactly integrate polynomials of as high a degree as possible for a
particular number of points (function evaluations). For smooth integrands, they
are accurate, computationally efficient formulae.
  The construction of the points and weights of a Gau{\ss} rule requires the
solution of a system of moment equations. In 1D, this system can be converted
to a linear system, and a unique solution is obtained, for which the points lie
within the region of integration, and the weights are all positive. These
properties help ensure numerical stability, and we describe the rules as
`good'. In the multidimensional case, the moment equations are nonlinear
algebraic equations, and a solution is not guaranteed to even exist, let alone
be good. The size and degree of the system grow with the degree of the desired
cubature rule. Analytic solution generally becomes impossible as the degree of
the polynomial equations to be solved goes beyond 4, and numerical
approximations are required. The uncertainty of the existence of solutions,
coupled with the size and degree of the system makes the problem daunting for
numerical methods.
  The construction of Gau{\ss} rules for (fully symmetric) $n$-dimensional
regions is easily specialised to the case of $U_3$, the unit sphere in 3D.
Despite the problems described above, for degrees up to 17, good Gau{\ss} rules
for $U_3$ have been constructed/discovered.

</DOC>
<DOC>
<DOCNO> 170804 </DOCNO>
Worldline Influence Functional: Abraham-Lorentz-Dirac-Langevin Equation


  We present a stochastic theory of charges moving in an electromagnetic field
using nonequilibrium quantum field theory. We give a first principles'
derivation of the Abraham-Lorentz-Dirac-Langevin equation which depicts the
quantum expectation value for a particle's trajectory and its stochastic
fluctuations by combining the worldline path integral quantization with the
Feynman-Vernon influence functional or closed-time-path effective action
methods. At lowest order, the equations of motion are approximated by a
stochastic Lorentz-Dirac equation.

</DOC>
<DOC>
<DOCNO> 72248 </DOCNO>
Extra dimensions and self-organizing criticality


  We discuss a possible explanation of the hierarchy problem within the
theories with spacetime dimensions higher than four. We show that the presence
of relatively (not hierarchically) large extra dimensions can significantly
alter the evolution of the Higgs field VEV, driving it to an infrared stable
fixed point $\sim M_{W}$. Such a behaviour results in self-organizing
criticality and naturally explains gauge hierarchy without any fine tuning of
the parameters.

</DOC>
<DOC>
<DOCNO> 69653 </DOCNO>
The O(infty) nonlinear sigma model out of equilibrium


  The out-of-equilibrium dynamics of the O(N+1) nonlinear sigma model in 1+1
dimensions is investigated in the large N limit. Regarding the nonlinearity as
the effect of a suitable large coupling limit of the O(N+1) \phi^4 model, we
first of all verify that the two limits commute, so that the O(infty) nonlinear
sigma model is uniquely defined. Such model can be completely renormalized also
in the out-of-equilibrium context, allowing us to study the consequences of its
asymptotic freedom on the time evolution far from equilibrium. In particular we
numerically study the spectrum of produced particles during the relaxation of
an initial condensate and find no evidence for parametric resonance, a result
that is consistent with the presence of the nonlinear contraint. Only a weak
nonlinear resonance at late times is observed.

</DOC>
<DOC>
<DOCNO> 10279 </DOCNO>
ARPES study of Pb doped Bi_2Sr_2CaCu_2O_8 - a new Fermi surface picture


  High resolution angle resolved photoemission data from Pb doped
Bi_2Sr_2CaCu_2O_8 (Bi2212) with suppressed superstructure is presented.
Improved resolution and very high momentum space sampling at various photon
energies reveal the presence of two Fermi surface pieces. One has the hole-like
topology, while the other one has its van Hove singularity very close to
(pi,0), its topology at some photon energies resembles the electron-like piece.
This result provides a unifying picture of the Fermi surface in the Bi2212
compound and reconciles the conflicting reports.

</DOC>
<DOC>
<DOCNO> 70229 </DOCNO>
Vector Boson Production at Hadron Colliders: Results from HERWIG and


  We discuss vector boson production at hadron colliders and the treatment of
the initial-state radiation according to Monte Carlo parton shower simulations
and resummed calculations. In particular, we investigate the effect of
matrix-element corrections to the HERWIG event generator on W/Z transverse
momentum distributions.

</DOC>
<DOC>
<DOCNO> 120877 </DOCNO>
Self-similar spherical collapse with non-radial motions


  We derive the asymptotic mass profile near the collapse center of an initial
spherical density perturbation, $\delta \propto M^{-\epsilon}$, of
collision-less particles with non-radial motions. We show that angular momenta
introduced at the initial time do not affect the mass profile. Alternatively,
we consider a scheme in which a particle moves on a radial orbit until it
reaches its turnaround radius, r_*. At turnaround the particle acquires an
angular momentum $L={\cal L} \sqrt{GM_* r_*}$ per unit mass, where M_* is the
mass interior to r_*. In this scheme, the mass profile is $M\propto
r^{3/(1+3\epsilon)}$ for all $\epsilon >0$, in the region $r/r_t\ll {\cal L}$,
where r_t is the current turnaround radius. If ${\cal L} \ll 1$ then the
profile in the region ${\cal L} \ll r/r_t \ll$ is $M\propto r$ for $\epsilon
<2/3$. The derivation relies on a general property of non-radial orbits which
is that ratio of the pericenter to apocenter is constant in a force field k(t)
r^{n} with k(t) varying adiabatically.

</DOC>
<DOC>
<DOCNO> 9723 </DOCNO>
Elasticity of nanometer-sized objects


  We initiate the development of a theory of the elasticity of nanoscale
objects based upon new physical concepts which remain properly defined on the
nanoscale. This theory provides a powerful way of understanding nanoscale
elasticity in terms of local group contributions and gives insight into the
breakdown of standard continuum relations. We also give two applications. In
the first, we show how to use the theory to derive a new relation between the
bending and stretching properties of nanomechanical resonators and to prove
that it is much more accurate than the continuum-based relations currently
employed in present experimental analyses. In the second, we use the new
approach to link features of the underlining electronic structure to the
elastic response of a silicon nanoresonator.

</DOC>
<DOC>
<DOCNO> 121854 </DOCNO>
The eclipsing binary millisecond pulsar PSR B1744-24A - possible test


  As presented by Nice et al. (2000), long-term timing of the eclipsing binary
PSR B1744-24A shows that the orbital period of this system decreases with a
time-scale of only ~ 200 Myr. To explain the much faster orbital period decay
than that predicted by only emission of the gravitational waves ~ 1000 Myr) we
propose that the orbital evolution of this system is also driven by magnetic
braking . If magnetic braking is to explain the rapid decay of the orbit, then
\lambda characterizing the effectiveness of the dynamo action in the stellar
convection zone in the magnetic stellar wind formula must be equal to 1.

</DOC>
<DOC>
<DOCNO> 117831 </DOCNO>
Structure and Evolution of the Envelopes of Deeply Embedded Massive


  The physical structure of the envelopes around a sample of fourteen massive
(1000-100,000 solar L) young stars is investigated on 100- 100,000 AU scales
using maps and spectra in submillimeter continuum and lines of C17O, CS and
H2CO. The total column densities and the temperature profiles are obtained by
fitting self-consistent dust models to submillimeter photometry. Both the
molecular line and dust emission data indicate density gradients ~r^{-alpha},
with alpha=1.0-1.5, significantly flatter than the alpha=2.0 generally found
for low-mass objects. This flattening may indicate that in massive young
stellar objects, nonthermal pressure is more important for the support against
gravitational collapse, while thermal pressure dominates for low-mass sources.
We find alpha=2 for two hot core-type sources, but regard this as an upper
limit since in these objects, the CS abundance may be enhanced in the warm gas
close to the star.

</DOC>
<DOC>
<DOCNO> 12234 </DOCNO>
Detecting Electronic States at Stacking Faults in Magnetic Thin Films by


  Co islands grown on Cu(111) with a stacking fault at the interface present a
conductance in the empty electronic states larger than the Co islands that
follow the stacking sequence of the Cu substrate. Electrons can be more easily
injected into these faulted interfaces, providing a way to enhance transmission
in future spintronic devices. The electronic states associated to the stacking
fault are visualized by tunneling spectroscopy and its origin is identified by
band structure calculations.

</DOC>
<DOC>
<DOCNO> 170019 </DOCNO>
Operationally Invariant Information in Quantum Measurements


  A new measure of information in quantum mechanics is proposed which takes
into account that for quantum systems the only feature known before an
experiment is performed are the probabilities for various events to occur. The
sum of the individual measures of information for mutually complementary
observations is invariant under the choice of the particular set of
complementary observations and conserved if there is no information exchange
with an environment. That operational quantum information invariant results in
N bits of information for a system consisting of N qubits.

</DOC>
<DOC>
<DOCNO> 121223 </DOCNO>
Frequency of Gas-Stellar Counterrotation


  We search for bulk counterrotation of the gas and stars in 67 galaxies of all
types and a wide range of luminosities. Bulk counterrotation characterizes
\~25-30% of E/S0's with extended gas, but at most a few percent of Sa-Sbc
spirals. For S0's, the frequency of counterrotation we derive agrees with
previous work, but we sample significantly fainter luminosities. Thus the
agreement suggests that similar formation mechanisms may operate over a wide
range of physical scales.

</DOC>
<DOC>
<DOCNO> 9720 </DOCNO>
T=0 Phase Diagram of the Double-Exchange Model


  We present the T=0 phase diagram of the double-exchange model (ferromagnetic
Kondo lattice model) for all values of the carrier concentration $n$ and Hund's
couplng $J$, within dynamical mean field theory. We find that depending on the
values of $n$ and $J$, the ground state is either a ferromagnet, a commensurate
antiferromagnet or some other incommensurate phase with intermediate wave
vectors . The antiferromagnetic phase is separated by first order phase
boundaries and wide regimes of phase separation. The transition from the
ferromagnetic phase to an incommensurate phase is second order.

</DOC>
<DOC>
<DOCNO> 10056 </DOCNO>
Population dynamics in a random environment


  We investigate the competition between barrier slowing down and proliferation
induced superdiffusion in a model of population dynamics in a random force
field. Numerical results in $d=1$ suggest that a new intermediate diffusion
behaviour appears. We introduce the idea of proliferation assisted barrier
crossing and give a Flory like argument to understand qualitatively this non
trivial diffusive behaviour. A one loop RG analysis close to the critical
dimension d_c=2 confirms that the random force fixed point is unstable and
flows towards an uncontrolled strong coupling regime.

</DOC>
<DOC>
<DOCNO> 120576 </DOCNO>
Cooling Radiation and the Lyman-alpha Luminosity of Forming Galaxies


  We examine the cooling radiation from forming galaxies in hydrodynamic
simulations of the LCDM model (cold dark matter with a cosmological constant),
focusing on the Ly-alpha line luminosities of high-redshift systems. Primordial
composition gas condenses within dark matter potential wells, forming objects
with masses and sizes comparable to the luminous regions of observed galaxies.
As expected, the energy radiated in this process is comparable to the
gravitational binding energy of the baryons, and the total cooling luminosity
of the galaxy population peaks at z ~= 2. However, in contrast to the classical
picture of gas cooling from the \sim 10^6 K virial temperature of a typical
dark matter halo, we find that most of the cooling radiation is emitted by gas
with T < 20,000 K. As a consequence, roughly 50% of this cooling radiation
emerges in the Ly-alpha line. While a galaxy's cooling luminosity is usually
smaller than the ionizing continuum luminosity of its young stars, the two are
comparable in the most massive systems, and the cooling radiation is produced
at larger radii, where the Ly-alpha photons are less likely to be extinguished
by dust. We suggest, in particular, that cooling radiation could explain the
two large (\sim 100 kpc), luminous (L_{Ly-alpha} \sim 10^{44} erg s^{-1})
``blobs'' of Ly-alpha emission found in Steidel et al.'s (1999) narrow band
survey of a z = 3 proto-cluster. Our simulations predict objects of the
observed luminosity at about the right space density, and radiative transfer
effects can account for the observed sizes and line widths. We discuss
observable tests of this hypothesis for the nature of the Ly-alpha blobs, and
we present predictions for the contribution of cooling radiation to the
Ly-alpha luminosity function of galaxies as a function of redshift.

</DOC>
<DOC>
<DOCNO> 122305 </DOCNO>
Evidence for Ionised Accretion Discs in Five Narrow-Line Seyfert 1


  (Abridged) We present the results of fitting ASCA spectra of six narrow-line
Seyfert 1 (NLS1) galaxies with the ionised reflection models of Ross & Fabian
(1993). We find that five of the galaxies (TONS 180, PKS 0558-504, Ark 564, Mrk
335 and PG 1244+026) are well fit by the ionised disc model, and these are
often better fits than the alternative models considered. The sixth galaxy, NGC
4051, has additional spectral complexity that cannot be well described by a
simple ionised disc model or any of the other alternative models. All six of
the NLS1s we considered show evidence for a broad Fe Kalpha line, but none of
the line centroids are consistent with emission from highly ionised Fe. This is
most likely due to the line being redshifted because of relativistic effects.
We note that sources with larger ionisation parameters tend to have larger Fe
Kalpha EWs. We interpret this as evidence that ionised Fe features are making
their presence felt in the spectra. Since most of our sources have steep
spectra, highly ionised features are predicted even by the new variable density
reflection models. The one source we analyse with a photon index less than two
has the lowest ionisation parameter in our sample. We conclude that our result
is the strongest evidence yet that NLS1 might have ionised accretion discs.
This result gives further weight to the hypothesis that these objects contain
rapidly accreting black holes.

</DOC>
<DOC>
<DOCNO> 116775 </DOCNO>
Extinction theorem for ultrafast pulses


  Instead of using frequency dependent refractive index, we propose to use the
extinction theorem to describe reflection and transmission of an ultrashort
pulse passing through the boundary. When the duration of the pulse is
comparable with the relaxation time, the results differ significantly from
those given by the traditional method, especially if the carrier frequency is
close to an absorbtion line. We compare the two approaches using the data of
GaAs in the infrared domain.

</DOC>
<DOC>
<DOCNO> 68054 </DOCNO>
Observational constraints on the spectral index of the cosmological


  We evaluate the observational constraints on the spectral index $n$, in the
context of the $\Lambda$CDM hypothesis which represents the simplest viable
cosmology. We first take $n$ to be practically scale-independent. Ignoring
reionization, we find at a nominal 2-$\sigma$ level $n\simeq 1.0 \pm 0.1$. If
we make the more realisitic assumption that reionization occurs when a fraction
$f\sim 10^{-5}$ to 1 of the matter has collapsed, the 2-$\sigma$ lower bound is
unchanged while the 1-$\sigma$ bound rises slightly. These constraints are
compared with the prediction of various inflation models. Then we investigate
the two-parameter scale-dependent spectral index, predicted by running-mass
inflation models, and find that present data allow significant scale-dependence
of $n$, which occurs in a physically reasonable regime of parameter space.

</DOC>
<DOC>
<DOCNO> 100960 </DOCNO>
Some properties of the solutions of obstacle problems with measure data


  We study some properties of the obstacle reactions associated with the
solutions of unilateral obstacle problems with measure data. These results
allow us to prove that, under very weak assumptions on the obstacles, the
solutions do not depend on the components of the negative parts of the data
which are concentrated on sets of capacity zero. The proof is based on a
careful analysis of the behaviour of the potentials of two mutually singular
measures near the points where both potentials tend to infinity.

</DOC>
<DOC>
<DOCNO> 70874 </DOCNO>
MATAD: a program package for the computation of MAssive TADpoles


  In the recent years there has been an enormous development in the evaluation
of higher order quantum corrections. An essential ingredient in the practical
calculations is provided by vacuum diagrams, i.e. integrals without external
momenta. In this paper a program package is described which can deal with one-,
two- and three-loop vacuum integrals with one non-zero mass parameter. The
principle structure is introduced and the main parts of the package are
described in detail. Explicit examples demonstrate the fields of application.

</DOC>
<DOC>
<DOCNO> 101841 </DOCNO>
Proof of the GGS Conjecture


  We prove the GGS conjecture (1993), due to Gerstenhaber, Giaquinto, and
Schack, which gives a particularly simple explicit quantization of classical
r-matrices for Lie algebras gl(n) in terms of an element R satisfying the
quantum Yang-Baxter equation and the Hecke condition. The r-matrices were
classified by Belavin and Drinfeld in the 1980s in terms of combinatorial
objects known as Belavin-Drinfeld triples. We prove this conjecture by showing
that the GGS matrix coincides with another quantization due to Etingof,
Schiffmann, and the author, which is a more general construction. We do this by
explicitly expanding the product from the aforementioned paper using detailed
combinatorial analysis in terms of Belavin-Drinfeld triples.

</DOC>
<DOC>
<DOCNO> 85069 </DOCNO>
An excess power statistic for detection of burst sources of


  We examine the properties of an excess power method to detect gravitational
waves in interferometric detector data. This method is designed to detect
short-duration (< 0.5 s) burst signals of unknown waveform, such as those from
supernovae or black hole mergers. If only the bursts' duration and frequency
band are known, the method is an optimal detection strategy in both Bayesian
and frequentist senses. It consists of summing the data power over the known
time interval and frequency band of the burst. If the detector noise is
stationary and Gaussian, this sum is distributed as a chi-squared (non-central
chi-squared) deviate in the absence (presence) of a signal. One can use these
distributions to compute frequentist detection thresholds for the measured
power. We derive the method from Bayesian analyses and show how to compute
Bayesian thresholds. More generically, when only upper and/or lower bounds on
the bursts duration and frequency band are known, one must search for excess
power in all concordant durations and bands. Two search schemes are presented
and their computational efficiencies are compared. We find that given
reasonable constraints on the effective duration and bandwidth of signals, the
excess power search can be performed on a single workstation. Furthermore, the
method can be almost as efficient as matched filtering when a large template
bank is required. Finally, we derive generalizations of the method to a network
of several interferometers under the assumption of Gaussian noise.

</DOC>
<DOC>
<DOCNO> 70669 </DOCNO>
What Can We Learn from Charmless Rare B Decays - the Past/Next 3 Years


  A personal perspective is given on physics of charmless rare B decays: 1997
-- 2003.

</DOC>
<DOC>
<DOCNO> 13844 </DOCNO>
Coherent transfer of Cooper pairs by a movable grain


  A coherent hybrid of states with different number of Cooper pairs can be
built in a superconductor grain as a result of periodically repeated discrete
encounters with bulk superconductor leads. As a direct manifestation of such
states a non-dissipative current depending on the phase difference between the
leads can be measured.

</DOC>
<DOC>
<DOCNO> 101657 </DOCNO>
Symplectic representations of inertia groups


  Suppose $\ell$ is a prime number, $\ell >3$, $K$ is a field that is an
unramified finite extension of the field $\Q_\ell$ of $\ell$-adic numbers, and
$G$ is a finite group that is a semi-direct product of a normal
$\ell'$-subgroup $H$ and a cyclic $\ell$-group $L$. Suppose that the group
algebra $K[H]$ is decomposable. If there exists an embedding of $G$ in the
symplectic group $\Sp_{2d}(K)$ for some positive integer $d$, then there exists
an embedding of $G$ in $\Sp_{2d}({\mathcal O}_K)$, where ${\mathcal O}_K$ is
the ring of integers of $K$.

</DOC>
<DOC>
<DOCNO> 102006 </DOCNO>
The $H^{\infty}-$calculus and sums of closed operators


  We develop a very general operator-valued functional calculus for operators
with an $H^{\infty}-$calculus. We then apply this to the joint functional
calculus of two commuting sectorial operators when one has an
$H^{\infty}$calculus. Using this we prove theorem of Dore-Venni type on sums of
commuting sectorial operators and apply our results to the problem of
$L_p-$maximal regularity. Our main assumption is the R-boundedness of certain
sets of operators, and therefore methods from the geometry of Banach spaces are
essential here. In the final section we exploit the special Banach space
structure of $L_1-$spaces and $C(K)-$spaces, to obtain some more detailed
results in this setting.

</DOC>
<DOC>
<DOCNO> 85562 </DOCNO>
Cosmic acceleration without quintessence


  It is argued that the Brans-Dicke theory may explain the present accelerated
expansion of the universe without resorting to a cosmological constant or
quintessence matter

</DOC>
<DOC>
<DOCNO> 40399 </DOCNO>
Pathological Science


  I discuss examples of what Dr. Irving Langmuir, a Nobel prize winner in
Chemistry, called "the science of things that aren't so." Some of his examples
are reviewed and others from High Energy Physics are added. It is hoped that
discussing these incidents will help us develop an understanding of some
potential pitfalls.

</DOC>
<DOC>
<DOCNO> 9272 </DOCNO>
Oscillatory Exchange Coupling and Positive Magnetoresistance in


  Oscillations in the exchange coupling between ferromagnetic
$La_{2/3}Ba_{1/3}MnO_3$ layers with paramagnetic $LaNiO_3$ spacer layer
thickness has been observed in epitaxial heterostructures of the two oxides.
This behavior is explained within the RKKY model employing an {\it ab initio}
calculated band structure of $LaNiO_3$, taking into account strong electron
scattering in the spacer. Antiferromagnetically coupled superlattices exhibit a
positive current-in-plane magnetoresistance.

</DOC>
<DOC>
<DOCNO> 151529 </DOCNO>
Supersymmetric Intersecting Domain Walls in Massive Hyper-Kahler Sigma


  The general scalar potential of D-dimensional massive sigma-models with eight
supersymmetries is found for $D=3,4$. These sigma models typically admit 1/2
supersymmetric domain wall solutions and we find, for a particular
hyper-K\"ahler target, exact 1/4 supersymmetric static solutions representing a
non-trivial intersection of two domain walls. We also show that the
intersecting domain walls can carry Noether charge while preserving 1/4
supersymmetry. We briefly discuss an application to the D1-D5 brane system.

</DOC>
<DOC>
<DOCNO> 85356 </DOCNO>
Qualitative analysis of dissipative cosmologies


  The evolution of an homogeneous and isotropic dissipative fluid is analyzed
using dynamical systems techniques. The dissipation is driven by bulk viscous
pressure and the truncated Israel-Stewart theory is used. Although almost all
solutions inflate, we show that only few of them can be considered as physical
solutions since the dominant energy condition is not satisfied.

</DOC>
<DOC>
<DOCNO> 85457 </DOCNO>
Noether Chargees for Self-interacting Quantum Field Theories in Curved


  We consider self-interacting, perturbative quantum field theory in a curved
spacetime background with a Killing vector field. We show that the action of
this spacetime symmetry on interacting field operators can be implemented by a
Noether charge which arises, in a certain sense, as a surface integral over the
time-component of some interacting Noether current-density associated with the
Killing field. The proof of this involves a demonstration of the corresponding
Ward identities. Our work is based on the perturbative construction by Brunetti
and Fredenhagen (Commun.Math.Phys. 208 (2000) 623-661) of self-interacting
quantum field theories in general globally hyperbolic spacetimes.

</DOC>
<DOC>
<DOCNO> 174557 </DOCNO>
The nuclear force in the third millennium


  I will review recent progress in our understanding of the nuclear force. In
the course of the 1990's, so-called high-precision, charge-dependent
nucleon-nucleon potentials have been constructed which are, essentially,
phenomenological models. These potentials are now commonly used as input for
exact few-body calculations and microscopic nuclear many-body theory. I will
critically analyses those models and point out their strenghts and weaknesses.
Particular emphasis will be on charge dependence. Other recent research was
conducted on a more basic level: understanding the nuclear force in terms of
the fundamental theory of strong interactions, QCD. Predictions from this
sector are typically qualitative in nature. Thus, the main problem of the
current status in the field is that quantitative models for the nuclear force
have a poor theoretical background, while theory based models yield poor
results. The chief challenge for the new millenium is to overcome this
discrepancy. Chiral effective field theory may be a suitable tool to solve the
problem.

</DOC>
<DOC>
<DOCNO> 116440 </DOCNO>
XAFS spectroscopy. I. Extracting the fine structure from the absorption


  Three independent techniques are used to separate fine structure from the
absorption spectra, the background function in which is approximated by (i)
smoothing spline. We propose a new reliable criterion for determination of
smoothing parameter and the method for raising of stability with respect to
k_min variation; (ii) interpolation spline with the varied knots; (iii) the
line obtained from bayesian smoothing. This methods considers various prior
information and includes a natural way to determine the errors of XAFS
extraction. Particular attention has been given to the estimation of
uncertainties in XAFS data. Experimental noise is shown to be essentially
smaller than the errors of the background approximation, and it is the latter
that determines the variances of structural parameters in subsequent fitting.

</DOC>
<DOC>
<DOCNO> 120834 </DOCNO>
Analysis of Energy Spectra with Low Photon Counts via Bayesian Posterior


  Over the past 10 years Bayesian methods have rapidly grown more popular as
several computationally intensive statistical algorithms have become feasible
with increased computer power. In this paper, we begin with a general
description of the Bayesian paradigm for statistical inference and the various
state-of-the-art model fitting techniques that we employ (e.g., Gibbs sampler
and Metropolis- Hastings). These algorithms are very flexible and can be used
to fit models that account for the highly hierarchical structure inherent in
the collection of high-quality spectra and thus can keep pace with the
accelerating progress of new space telescope designs. The methods we develop,
which will soon be available in the CIAO software package, explicitly model
photon arrivals as a Poisson process and, thus, have no difficulty with high
resolution low count X-ray and gamma-ray data. We expect these methods to be
useful not only for the recently launched Chandra X-ray observatory and XMM but
also new generation telescopes such as Constellation X, GLAST, etc. In the
context of two examples (Quasar S5 0014+813 and Hybrid-Chromosphere Supergiant
Star alpha TrA) we illustrate a new highly structured model and how Bayesian
posterior sampling can be used to compute estimates, error bars, and credible
intervals for the various model parameters.

</DOC>
<DOC>
<DOCNO> 11985 </DOCNO>
Non-extensivity Effects and the Highest Energy Cosmic Ray Affair


  Recent measurements of the cosmic microwave background confirm that it is
described by a Planckian distribution with high precision. It is
non-extensivity bounded to be less than some parts in $10^5$, or to some parts
in $10^4$ at most. This deviation may appear minuscule, but may have a
non-negligible effect on a particle propagating through this background over
the course of millions of years. In this paper we analyze the possible
influence of such a slight deviation upon the propagation of nuclei and protons
of ultra-high energy. These particles interact via photopion and
photodisintegration processes which we examine taking into account a slight
non-extensive background. We show that such a deviation does not exhibit a
significant difference in the energy attenuation length of extremely high
energy cosmic rays.

</DOC>
<DOC>
<DOCNO> 80785 </DOCNO>
SU(2) gluon propagator on a coarse anisotropic lattice


  We calculated the SU(2) gluon propagator in Landau gauge on an anisotropic
coarse lattice with the improved action. The standard and the improved scheme
are used to fix the gauge in this work. Even on the coarse lattice the lattice
gluon propagator can be well described by a function of the continuous
momentum. The effect of the improved gauge fixing scheme is found not to be
apparent. Based on the Marenzoni's model, the mass scale and the anomalous
dimension are extracted and can be reasonably extrapolated to the continuum
limit with the values $\alpha\sim 0.3$ and $M\sim 600MeV$. We also extract the
physical anisotropy $\xi$ from the gluon propagator due to the explicit $\xi$
dependence of the gluon propagator.

</DOC>
<DOC>
<DOCNO> 100157 </DOCNO>
Ribbon-moves of 2-links preserve the \mu-invariant of 2-links


  We introduce ribbon-moves of 2-knots, which are operations to make 2-knots
into new 2-knots by local operations in B^4. (We do not assume the new knots is
not equivalent to the old ones.)
  Let L_1 and L_2 be 2-links. Then the following hold. (1) If L_1 is
ribbon-move equivalent to L_2, then we have \mu(L_1)=\mu(L_2).
  (2) Suppose that L_1 is ribbon-move equivalent to L_2. Let W_i be arbitrary
Seifert hypersurfaces for L_i. Then the torsion part of H_1(W_1)+H_1(W_2) is
congruent to G+G for a finite abelian group G.
  (3) Not all 2-knots are ribbon-move equivalent to the trivial 2-knot.
  (4) The inverse of (1) is not true.
  (5) The inverse of (2) is not true.
  Let L=(L_1,L_2) be a sublink of homology boundary link. Then we have: (i) L
is ribbon-move equivalent to a boundary link. (ii) \mu(L)= \mu(L_1) + \mu(L_2).
  We would point out the following facts by analogy of the discussions of
finite type invariants of 1-knots although they are very easy observations. By
the above result (1), we have: the \mu-invariant of 2-links is an order zero
finite type invariant associated with ribbon-moves and there is a 2-knot whose
\mu-invariant is not zero. The mod 2 alinking number of (S^2, T^2)-links is an
order one finite type invariant associated with the ribbon-moves and there is
an (S^2, T^2)-link whose mod 2 alinking number is not zero.

</DOC>
<DOC>
<DOCNO> 10558 </DOCNO>
Motion in a rocked ratchet with spatially periodic friction


  We present a detailed study of the transport and energetics of a Brownian
particle moving in a periodic potential in the presence of an adiabatic
external periodic drive. The particle is considered to move in a medium with
periodic space dependent friction with the same periodicity as that of the
potential but with a phase lag. We obtain several results, most of them arising
due to the medium being inhomogeneous and are sensitive to the phase lag. When
the potential is symmetric we show that efficiency of energy transduction can
be maximised as a function of noise strength or temperature. However, in the
case of asymmtertic potential the temperature may or may not facilitate the
energy conversion but current reversals can be obtained as a function of
temperature and the amplitude of the periodic drive. The reentrant behaviour of
current can also be seen as a function of phase lag.

</DOC>
<DOC>
<DOCNO> 12703 </DOCNO>
Depinning of a superfluid vortex line by Kelvin waves


  We measure the interaction of a single superfluid vortex with surface
irregularities. While vortex pinning in superconductors usually becomes weaker
at higher temperatures, we find the opposite behavior. The pinning steadily
increases throughout our measurement range, from 0.15Tc to over 0.5Tc. We also
find that moving the other end of the vortex decreases the pinning, so we
propose Kelvin waves along the vortex as a depinning mechanism.

</DOC>
<DOC>
<DOCNO> 121799 </DOCNO>
Constraints on Galaxy Bias, Matter Density, and Primordial


  We compute the bispectrum for the \IRAS PSCz catalog and find that the galaxy
distribution displays the characteristic signature of gravity. Assuming
Gaussian initial conditions, we obtain galaxy biasing parameters
$1/b_1=1.20^{+0.18}_{-0.19}$ and $b_2/b_1^2=-0.42\pm0.19$, with no sign of
scale-dependent bias for $k\leq 0.3$ h/Mpc. These results impose stringent
constraints on non-Gaussian initial conditions. For dimensional scaling models
with $\chi^2_N$ statistics, we find N>49, which implies a constraint on
primordial skewness $B_3<0.35$.

</DOC>
<DOC>
<DOCNO> 13354 </DOCNO>
Ab initio description of tunnel junctions


  Based on spin-density functional theory we calculate the electronic structure
of a tunnel junction consisting of two magnetic Fe layers separated by an
insulating vacuum barrier selfconsistently. For the conductance the Landauer
formula is evaluated in the ballistic limit as function of the magnetic
configuration. Based on these conductances the tunnel magnetoresistance (TMR)
ratio is obtained. We investigate the relation between TMR ratio and spin
polarization of the electronic structure at the metal/insulator interface.

</DOC>
<DOC>
<DOCNO> 117270 </DOCNO>
Particle Propagation Upstream of CIR Shocks


  The first high solar latitude pass of the Ulysses spacecraft revealed the
presence of MeV particle increases up to latitudes above 60 degrees, well
outside the CIR belt but associated in time with the regular passage of these
plasma interfaces at more equatorial latitudes. The particle increases have
been explained variously as due to diffusion from a field line connection with
a CIR at a greater distance, perpendicular diffusion in latitude, propagation
from the inner Corona or an acceleration process on a connecting field line.
Numerical solutions to the 1-D propagation equation upstream of a CIR shock for
reasonable diffusion mean free paths are shown here to limit the source of the
increases to within about 2 AU of the CIR's, asssuming the CIR's either trap or
accelerate energetic particles and they diffuse from the nearby CIR interface.
The problem of allowing propagation from the CIR's is eased if the CIRs are
located according to the predictions for the current sheet with a solar source
surface at $2.5 R_{s}$, rather than at $3.25 R_{s}$. Energetic electron
observations showing delays with respect to the CIR-associated ions suggest
possibly an acceleration in the inner corona, rather than in the CIR-associated
shock. A more likely explanation, however, is the ability of electrons to take
a longer a longer route, from beyond the point of observation, than for that of
the ions and yet arrive within a few days of CIR closest approach time.

</DOC>
<DOC>
<DOCNO> 8674 </DOCNO>
Single particle slow dynamics of confined water


  Molecular dynamics simulations of SPC/E water confined in a Silica pore are
presented. The simulations have been performed at different hydration levels
and temperatures to study the single-particle dynamics. Due to the confinement
and to the presence of a hydrophilic surface, the dynamic behaviour of the
liquid appears to be strongly dependent on the hydration level. On lowering
temperature and/or hydration level the intermediate scattering function
displays a double-step relaxation behaviour whose long time tail is strongly
non-exponential. At higher hydrations two quite distinct subsets of water
molecules are detectable. Those belonging to the first two layers close to the
substrate suffer a severe slowing down already at ambient temperature. While
the behaviour of the remaining ones is more resemblant to that of supercooled
bulk SPC/E water. At lower hydrations and/or temperatures the onset of a slow
dynamics due to the cage effect and a scenario typical of supercooled liquids
approaching the kinetic glass transition is observed. Moreover, for low
hydrations and/or temperatures, the intermediate scattering function clearly
displays an overshoot, which can be assigned to the so called ``Boson Peak''.

</DOC>
<DOC>
<DOCNO> 120499 </DOCNO>
Prediction of nuclear reaction rates for astrophysics


  This is an overview over the prediction of astrophysical reaction rates in
the statistical model, with special emphasis on the parametrization of optical
alpha+nucleus potentials.

</DOC>
<DOC>
<DOCNO> 150802 </DOCNO>
Schwinger-Dyson = Wheeler-DeWitt: gauge theory observables as bulk


  We argue that the second-order gauge-invariant Schwinger-Dyson operator of a
gauge theory is the Wheeler-DeWitt operator in the dual string theory. Using
this identification, we construct a set of operators in the gauge theory that
correspond to excitations of gravity in the bulk. We show that these gauge
theory operators have the expected properties for describing the semiclassical
local gravity theory.

</DOC>
<DOC>
<DOCNO> 8074 </DOCNO>
Localization in Artificial Disorder - Two Coupled Quantum Dots


  Using Single Electron Capacitance Spectroscopy, we study electron additions
in quantum dots containing two potential minima separated by a shallow barrier.
Analysis of addition spectra in magnetic field allows us to distinguish whether
electrons are localized in either potential minimum or delocalized over the
entire dot. We demonstrate that high magnetic field abruptly splits up a
low-density droplet into two smaller fragments, each residing in a potential
minimum. An unexplained cancellation of electron repulsion between electrons in
these fragments gives rise to paired electron additions.

</DOC>
<DOC>
<DOCNO> 100683 </DOCNO>
L-functions and random matrices


  In 1972 H. L. Montgomery announced a remarkable connection between the
distribution of the zeros of the Riemann zeta-function and the distribution of
eigenvalues of large random Hermitian matrices. Since then a number of
startling developments have occurred making this connection more profound. In
particular, random matrix theory has been found to be an extremely useful
predictive tool in the theory of L-functions. In this article we will try to
explain these recent developments and indicate some diretions for future
investigations.

</DOC>
<DOC>
<DOCNO> 85442 </DOCNO>
Yes, semiclassical zero temperature black holes exist


  In a recent paper (gr-qc/0002007), Anderson, Hiscock and Taylor claimed that
"in all physically realistic cases, macroscopic zero temperature black hole
solutions do not exist." We show this conclusion was reached on the basis of an
incorrect calculation.

</DOC>
<DOC>
<DOCNO> 120649 </DOCNO>
Hierarchical Galaxy Formation


  We describe the GALFORM semi-analytic model for calculating the formation and
evolution of galaxies in hierarchical models. It improves upon, and extends,
the Cole et al 1994 model. The model employs a new Monte-Carlo algorithm to
follow the merging evolution of dark matter halos with arbitrary mass
resolution. It incorporates realistic descriptions of the density profiles of
dark matter halos and their gas content; follows the chemical evolution of gas
and stars, and the associated production of dust; and includes a detailed
calculation of the sizes of disks and spheroids. Wherever possible, our
prescriptions for modelling individual physical processes are based on results
of numerical simulations. We apply our methods to the LCDM cosmology
(Omega_0=0.3, Lambda_0=0.7), and find good agreement with a wide range of
properties of the local galaxy population: the B-band and K-band luminosity
functions, the distribution of colours for the population as a whole, the ratio
of ellipticals to spirals, the distribution of disk sizes, and the current cold
gas content of disks. (Abridged)

</DOC>
<DOC>
<DOCNO> 102294 </DOCNO>
Finite quantum groupoids and inclusions of finite type


  Bialgebroids, separable bialgebroids, and weak Hopf algebras are compared
from a categorical point of view. Then properties of weak Hopf algebras and
their applications to finite index and finite depth inclusions of von Neumann
algebras are shortly reviewed. A hint is given at a duality between bialgebroid
actions and abstract inclusions in 2-categories.

</DOC>
<DOC>
<DOCNO> 117923 </DOCNO>
K-Band Spectroscopy of an Obscured Massive Stellar Cluster in the


  We present infrared spectroscopy of the Antennae Galaxies (NGC 4038/4039)
with NIRSPEC at the W. M. Keck Observatory. We imaged the star clusters in the
vicinity of the southern nucleus (NGC 4039) in 0.39" seeing in K-band using
NIRSPEC's slit-viewing camera. The brightest star cluster revealed in the
near-IR (M_K(0) = -17.9) is insignificant optically, but coincident with the
highest surface brightness peak in the mid-IR (12-18 um) ISO image presented by
Mirabel et al (1998). We obtained high signal-to-noise 2.03-2.45 um spectra of
the nucleus and the obscured star cluster at R = 1900.
  The cluster is very young (age ~ 4 Myr), massive (M ~ 16E6 M_sun), and
compact (density ~ 115 M_sun pc^(-3) within a 32 pc half-light radius),
assuming a Salpeter IMF (0.1-100 M_sun). Its hot stars have a radiation field
characterized by T_eff ~ 39,000 K, and they ionize a compact HII region with
n_e ~ 10^4 cm^(-3). The stars are deeply embedded in gas and dust (A_V = 9-10
mag), and their strong FUV field powers a clumpy photodissociation region with
densities n_H > 10^5 cm^(-3) on scales of ~ 200 pc, radiating L{H_2 1-0 S(1)}=
9600 L_sun.

</DOC>
<DOC>
<DOCNO> 120289 </DOCNO>
Efficiencies of Low-Mass Star and Star Cluster Formation


  Using a quantitative model for bipolar outflows driven by hydromagnetic
protostellar winds, we calculate the efficiency of star formation assuming that
available gas is either converted into stars or ejected in outflows. We
estimate the efficiency of a single star formation event in a protostellar
core, finding 25%-70% for cores with various possible degrees of flattening.
The core mass function and the stellar initial mass function have similar
slopes, because the efficiency is not sensitive to its parameters. We then
consider the disruption of gas from a dense molecular clump in which a cluster
of young stars is being born. In both cases, we present analytical formulae for
the efficiencies that compare favorably against observations and, for clusters,
against numerical simulations. We predict efficiencies in the range 30%-50% for
the regions that form clusters of low-mass stars. In our model, star formation
and gas dispersal happen concurrently. We neglect the destructive effects of
massive stars: our results are therefore upper limits to the efficiency in
regions more massive than about 3000 Msun.

</DOC>
<DOC>
<DOCNO> 71768 </DOCNO>
Annihilations from the Galactic Centre


  A massive black hole is present at the centre of our galaxy and inevitably
accretes dark matter particles, creating a region of very high particle
density. The annihilation rate is enhanced with a large number of e+e- pairs
produced either directly or by successive decays of mesons. We evaluate the
synchrotron emission (and self-absorption) associated with the propagation of
these particles through the galactic magnetic field and give constraints on the
values of mass and cross section of the dark matter particles.

</DOC>
<DOC>
<DOCNO> 119456 </DOCNO>
Composition of UHE Cosmic Ray Primaries


  Project GRAND presents results on the atomic composition of primary cosmic
rays. This is accomplished by determining the average height of primary
particles that cause extensive air showers detected by Project GRAND. Particles
with a larger cross sectional area, such as iron nuclei, are likely to start an
extensive air shower higher in the atmosphere whereas protons, with a smaller
cross section, would pass through more air before interacting and thus start
showers at lower heights. Such heights can be determined by extrapolating
identified muon tracks backward (upward) to determine their height of origin
(Gress et al., 1997). Since muons are from the top, hadronic part of the
shower, they are a good estimator for the beginning of the shower. The data for
this study were taken during the previous year with 20 million shower events.

</DOC>
<DOC>
<DOCNO> 118499 </DOCNO>
A Simple Model for the Absorption of Starlight by Dust in Galaxies


  We present a new model to compute the effects of dust on the integrated
spectral properties of galaxies, based on an idealized prescription of the main
features of the interstellar medium (ISM). The model includes the ionization of
HII regions in the interiors of the dense clouds in which stars form and the
influence of the finite lifetime of these clouds on the absorption of
radiation. We compute the production of emission lines and the absorption of
continuum radiation in the HII regions and the subsequent transfer of line and
continuum radiation in the surrounding HI regions and the ambient ISM. This
enables us to interpret simultaneously all the observations of a homogeneous
sample of nearby UV-selected starburst galaxies, including the ratio of far-IR
to UV luminosities, the ratio of Halpha to Hbeta luminosities, the Halpha
equivalent width, and the UV spectral slope. We show that the finite lifetime
of stellar birth clouds is a key ingredient to resolve an apparent discrepancy
between the attenuation of line and continuum photons in starburst galaxies. In
addition, we find that an effective absorption curve proportional to
lambda^-0.7 reproduces the observed relation between the ratio of far-IR to UV
luminosities and the UV spectral slope. We interpret this relation most simply
as a sequence in the overall dust content of the galaxies. The shallow
wavelength dependence of the effective absorption curve is compatible with the
steepness of known extinction curves if the dust has a patchy distribution. In
particular, we find that a random distribution of discrete clouds with optical
depths similar to those in the Milky Way provides a consistent interpretation
of all the observations. Our model for absorption can be incorporated easily
into any population synthesis model. (abridged)

</DOC>
<DOC>
<DOCNO> 68780 </DOCNO>
Pair production of neutralinos via photon-photon collisions


  We investigated the production of neutralino pairs via photon-photon
collisions in the minimal supersymmetric model(MSSM) at future linear
colliders. The numerical analysis of their production rates is carried out in
the mSUGRA scenario. The results show that this cross section can reach about
18 femto barn for $\tilde{\chi}^{0}_{1} \tilde{\chi}^{0}_{2}$ pair production
and 9 femto barn for $\tilde{\chi}^{0}_{2}\tilde{\chi}^{0}_{2}$ pair production
with our chosen input parameters.

</DOC>
<DOC>
<DOCNO> 85493 </DOCNO>
Quiescent cosmological singularities


  I discuss recent work (gr-qc/0001047) on non-oscillatory singularities in
four dimensional space-times with scalar field or stiff fluid matter, in the
context of the BKL proposal.

</DOC>
<DOC>
<DOCNO> 117298 </DOCNO>
Are Short and Long Gamma Ray Bursts Really of Different Origin?


  It is shown that short and long gamma ray bursts (GRBs) are of the same
origin and, furthermore, correlated with their duration.

</DOC>
<DOC>
<DOCNO> 83386 </DOCNO>
A Resolution Calculus for Dynamic Semantics


  This paper applies resolution theorem proving to natural language semantics.
The aim is to circumvent the computational complexity triggered by natural
language ambiguities like pronoun binding, by interleaving pronoun binding with
resolution deduction. Therefore disambiguation is only applied to expression
that actually occur during derivations.

</DOC>
<DOC>
<DOCNO> 170323 </DOCNO>
Security of EPR-based Quantum Key Distribution


  We propose a proof of the security of EPR-based quantum key distribution
against enemies with unlimited computational power. The proof holds for a
protocol using interactive error-reconciliation scheme. We assume in this paper
that the legitimate parties receive a given number of single photon signals and
that their measurement devices are perfect.

</DOC>
<DOC>
<DOCNO> 116307 </DOCNO>
Pressure dependence of the Mg $3s4s^3S_1 \to 3s3p^3P_{0,1,2}$ transition


  The pressure shifts of the $3s4s^3S_1 \to 3s3p^3P_{0,1,2}$ transition of
magnesium atoms immersed in superfluid helium have been measured at $(1.3\pm0.1
)$K between saturated vapour pressure and $24 $bar. The wavelength is blue
shifted linearly by $(0.07\pm0.01) \frac{nm}{bar}$. This value can be
satisfactorily described in the framework of the standard bubble model.

</DOC>
<DOC>
<DOCNO> 84778 </DOCNO>
On Imprisoned Curves and b-length in General Relativity


  This paper is concerned with two themes: imprisoned curves and the b-length
functional. In an earlier paper by the author, it was claimed that an endless
incomplete curve partially imprisoned in a compact set admits an endless null
geodesic cluster curve. Unfortunately, the proof was flawed. We give an outline
of the problem and remedy the situation by providing a proof by different
methods. Next, we obtain some results concerning the structure of b-length
neighbourhoods, which gives a clue to how the geometry of a spacetime is
encoded in the pseudo-orthonormal frame bundle equipped with the b-metric. We
also show that a previous result by the author, proving total degeneracy of a
b-boundary fibre in some cases, does not apply to imprisoned curves. Finally,
we correct some results in the literature linking the b-lengths of general
curves in the frame bundle with the b-length of the corresponding horizontal
curves.

</DOC>
<DOC>
<DOCNO> 8524 </DOCNO>
Heat conduction in one dimensional nonintegrable systems


  Two classes of 1D nonintegrable systems represented by the Fermi-Pasta-Ulam
(FPU) model and the discrete $\phi^4$ model are studied to seek a generic
mechanism of energy transport in microscopic level sustaining macroscopic
behaviors. The results enable us to understand why the class represented by the
$\phi^4$ model has a normal thermal conductivity and the class represented by
the FPU model does not even though the temperature gradient can be established.

</DOC>
<DOC>
<DOCNO> 9487 </DOCNO>
Quantitative imaging of dielectric permittivity and tunability with a


  We describe the use of a near-field scanning microwave microscope to image
the permittivity and tunability of bulk and thin film dielectric samples on a
length scale of about 1 micron. The microscope is sensitive to the linear
permittivity, as well as to nonlinear dielectric terms, which can be measured
as a function of an applied electric field. We introduce a versatile finite
element model for the system, which allows quantitative results to be obtained.
We demonstrate use of the microscope at 7.2 GHz with a 370 nm thick barium
strontium titanate thin film on a lanthanum aluminate substrate. This technique
is nondestructive and has broadband (0.1-50 GHz) capability. The sensitivity of
the microscope to changes in relative permittivity is 2 at permittivity = 500,
while the nonlinear dielectric tunability sensitivity is 10^-3 cm/kV.

</DOC>
<DOC>
<DOCNO> 117985 </DOCNO>
Simulating the effects of intergalactic grey dust


  Using a high-resolution cosmological hydrodynamic simulation, we present a
method to constrain extinction due to intergalactic grey dust based on the
observed magnitudes of distant Type IA supernovae. We apply several simple
prescriptions to relate the intergalactic dust density to the gas density in
the simulation, thereby obtaining dust extinctions that may be directly
compared to the observed distribution of supernova magnitudes. Our analysis is
sensitive to the spatial distribution of grey dust, but is not dependent on its
intrinsic properties such as its opacity or grain size. We present an
application of our technique to the supernova data of Perlmutter et al., who
find that their high redshift sample is ~0.2 magnitudes fainter than the
expectation for a non-accelerating, low-density universe. We find that for grey
dust to be responsible, it must be distributed quite smoothly, e.g., tracing
intergalactic gas. More realistic dust distributions, such as dust tracing the
metal density, are inconsistent with observations at the 1.5-2 sigma level.
Upcoming observations and improved modelling of the dust distribution should
lead to stronger constraints on intergalactic grey dust extinction.

</DOC>
<DOC>
<DOCNO> 11147 </DOCNO>
Dynamics of Fluctuating Bose-Einstein Condensates


  We present a generalized Gross-Pitaevskii equation that describes also the
dissipative dynamics of a trapped partially Bose condensed gas. It takes the
form of a complex nonlinear Schr\"odinger equation with noise. We consider an
approximation to this Langevin field equation that preserves the correct
equilibrium for both the condensed and the noncondensed parts of the gas. We
then use this formalism to describe the reversible formation of a
one-dimensional Bose condensate, and compare with recent experiments. In
addition, we determine the frequencies and the damping of collective modes in
this case.

</DOC>
<DOC>
<DOCNO> 71135 </DOCNO>
The decay of the observed $J^{PC}=1^{-+}$ (1400) and


  We study the possible interpretation of the two exotic resonances $J^{PC}=
1^{-+}$ at 1400 and 1600 MeV, claimed to be observed by BNL, decaying
respectively into $\eta\pi$, $\eta'\pi$, $f_{1}\pi$ and $\rho\pi$. These
objects are interpreted as hybrid mesons, in the quark-gluon constituent model
using a chromoharmonic confining potentiel.
  The quantum numbers $J^{PC}I^{G} = 1^{-+} 1^{-}$ can be considered in a
constituent model as an hybrid meson ($q \bar q g$). The lowest $J^{PC}=
1^{-+}$states may be built in two ways : $l_{g}$=1 (gluon-excited)
corresponding to an angular momentum between the gluon and ($q \bar q$) system,
while $l_{q \bar q}=1$ (quarks-excited) corresponds to an angular momentum
between $q$ and $\bar q$. For the gluon-excited mode $1^{-+}$ hybrids, we find
the decay dominated by the $b_{1}\pi$ channel, and by the $\rho \pi$ channel
for the quark-excited mode. In our model, neither the quark-excited nor the
gluon-excited $1^{-+}$ (1400 MeV) hybrids can decay into $\eta\pi$ and
$\eta'\pi$, in contradiction with experiment. Hence, the 1400 MeV resonance
seems unlikely to be an hybrid state. The $1^{-+}$ (1600 MeV) gluon-excited
hybrid is predicted with too large a total decay width, to be considered as an
hybrid candidate. On the contrary the quark-excited mode has a total decay
width around 165 MeV, with a $\rho \pi$ preferred decay channel, in agreement
with BNL. Our conclusion is that {\it{this resonance may be considered as a
hybrid meson in the quark-excited mode}}

</DOC>
<DOC>
<DOCNO> 85407 </DOCNO>
Symmetries of homogeneous cosmologies


  We reformulate the dynamics of homogeneous cosmologies with a scalar field
matter source with an arbitrary self-interaction potential in the language of
jet bundles and extensions of vector fields. In this framework, the
Bianchi-scalar field equations become subsets of the second Bianchi jet bundle,
$J^2$, and every Bianchi cosmology is naturally extended to live on a variety
of $J^2$. We are interested in the existence and behaviour of extensions of
arbitrary Bianchi-Lie and variational vector fields acting on the Bianchi
variety and accordingly we classify all such vector fields corresponding to
both Bianchi classes $A$ and $B$. We give examples of functions defined on
Bianchi jet bundles which are constant along some Bianchi models (first
integrals) and use these to find particular solutions in the Bianchi total
space. We discuss how our approach could be used to shed new light to questions
like isotropization and the nature of singularities of homogeneous cosmologies
by examining the behaviour of the variational vector fields and also give rise
to interesting questions about the `evolution' and nature of the cosmological
symmetries themselves.

</DOC>
<DOC>
<DOCNO> 120744 </DOCNO>
The Interaction of Type Ia Supernovae with their Surroundings: The


  The evolution of Type Ia supernovae in the surrounding medium is studied
using 2-dimensional numerical hydrodynamic simulations. The ejecta are assumed
to be described by an exponential density profile, following the work of
Dwarkadas & Chevalier (1998). The case of a circumstellar (CS) region formed by
mass loss from the progenitor or a companion star is also considered. The
decelerating contact discontinuity is found to be Rayleigh-Taylor (R-T)
unstable, as expected, and the nature of the instability is studied in detail
for 2 cases: 1) a constant density ambient medium, and 2) a CS medium whose
density goes as r^{-2}. The nature of the instability is found to be different
in both cases. In the case of a CS medium the instability is much better
resolved, and a fractal-like structure is seen. In the case of a constant
density medium the extent of growth is less, and the R-T fingers are found to
be limited by the presence of Kelvin-Helmholtz mushroom caps at the tips of the
fingers. The unstable region is far enough away from the reverse shock that the
latter is not affected by the mixing taking place in the interaction region. In
contrast the reverse shock in the case of a CS medium is found to be rippled
due to the formation of instabilities. In neither case is the outer shock front
affected. These results are consistent with similar studies of power-law ejecta
profiles conducted by Chevalier, Blondin & Emmering (1992). Our results are
then applied to Tycho's supernova remnant.

</DOC>
<DOC>
<DOCNO> 85231 </DOCNO>
Resource Letter on geometrical results for Embeddings and Branes


  Due to the recent renewal in the interest for embedded surfaces we provide a
list of commented references of interest.

</DOC>
<DOC>
<DOCNO> 9364 </DOCNO>
Critical exponents of plane meanders


  Meanders form a set of combinatorial problems concerned with the enumeration
of self-avoiding loops crossing a line through a given number of points, $n$.
Meanders are considered distinct up to any smooth deformation leaving the line
fixed. We use a recently developed algorithm, based on transfer matrix methods,
to enumerate plane meanders. This allows us to calculate the number of closed
meanders up to $n=48$, the number of open meanders up to $n=43$, and the number
of semi-meanders up to $n=45$. The analysis of the series yields accurate
estimates of both the critical point and critical exponent, and shows that a
recent conjecture for the exact value of the semi-meander critical exponent is
unlikely to be correct, while the conjectured exponent value for closed and
open meanders is not inconsistent with the results from the analysis.

</DOC>
<DOC>
<DOCNO> 71816 </DOCNO>
$B\to \pi \rho$, $\pi \omega$ Decays in Perturbative QCD Approach


  We calculate the branching ratios and CP asymmetries for $B^0 \to
\pi^+\rho^-$, $B^0 \to \rho^+\pi^-$, $B^+ \to \rho^+\pi^0$, $B^+ \to
\pi^+\rho^0$, $B^0 \to \pi^0\rho^0$, $B^+ \to \pi^+\omega$ and $B^0 \to
\pi^0\omega$ decays, in a perturbative QCD approach. In this approach, we
calculate non-factorizable and annihilation type contributions, in addition to
the usual factorizable contributions. Our result is in agreement with the
measured branching ratio of $B^0/\bar B^0 \to \pi^\pm\rho^\mp$, $B^\pm \to
\pi^\pm\rho^0$, $\pi^\pm \omega$ by CLEO and BABAR collaboration. We also
predict large CP asymmetries in these decays. These channels are useful to
determine the CKM angle $\phi_2$.

</DOC>
<DOC>
<DOCNO> 151372 </DOCNO>
Green-Schwarz Superstring Action in Type IIA Supergravity Backgrounds


  This paper has been withdrawn by the authors because the action has already
been given in hep-th/9907202.

</DOC>
<DOC>
<DOCNO> 10247 </DOCNO>
Magnitude and Sign Correlations in Heartbeat Fluctuations


  We propose an approach for analyzing signals with long-range correlations by
decomposing the signal increment series into magnitude and sign series and
analyzing their scaling properties. We show that signals with identical
long-range correlations can exhibit different time organization for the
magnitude and sign. We find that the magnitude series relates to the nonlinear
properties of the original time series, while the sign series relates to the
linear properties. We apply our approach to the heartbeat interval series and
find that the magnitude series is long-range correlated, while the sign series
is anticorrelated and that both magnitude and sign series may have clinical
applications.

</DOC>
<DOC>
<DOCNO> 70003 </DOCNO>
Quintessential Brane and the Cosmological Constant


  We consider a quintessential sector realized on a hidden brane with a tiny
warp factor, which implies a small value of the effective four-dimensional
cosmological constant through an equation of motion for the quintessential
scalar.

</DOC>
<DOC>
<DOCNO> 10129 </DOCNO>
Coexistent States of Charge Density Wave and Spin Density Wave in


  The coexistent state of the spin density wave (SDW) and the charge density
wave (CDW) in the one-dimensional systems is studied by the mean field
approximation at T=0 in various electron-filling cases. We find that the
coexistent state of SDW and CDW is stabilized when the on-site and the
inter-site Coulomb interactions have the values estimated for the organic
conductors. The ground state energies have cusp-like minima at 1/4, 3/8, 5/12,
7/16, 7/20 and 9/20-fillings.

</DOC>
<DOC>
<DOCNO> 170593 </DOCNO>
Relativity of Entanglement


  It has been suggested recently that various entanglement measures for
bipartite mixed states do not give the same ordering in general even in the
asymptotic cases [S. Virmani and M. B. Plenio, Phys. Lett. A {\bf 268}, 31
(2000)]. That is, for certain two mixed states, the order of
entanglement-degree depends on the type of the measures. Therefore, there exist
incomparable pairs of mixed states which cannot be transformed to each other
with unit efficiency by any combinations of local quantum operations and
classical communications. We make an analogy of the relativity of
entanglement-degree orders to relativity of temporal orders in the special
theory of relativity.

</DOC>
<DOC>
<DOCNO> 101634 </DOCNO>
Group algebras whose involutory units commute


  Let K be a field of characteristic 2 and G a nonabelian locally finite
2-group. Let V(KG) be the group of units with augmentation 1 in the group
algebra KG. An explicit list of groups is given, and it is proved that all
involutions in V(KG) commute with each other if and only if G is isomorphic to
one of the groups on this list. In particular, this property depends only on G
and not at all on K.

</DOC>
<DOC>
<DOCNO> 70730 </DOCNO>
Lepton Masses and Mixing Angles with Spontaneously Broken O(3) Flavor


  We present a model based on an O(3) flavor symmetry and a minimal extension
of the scalar sector to induce hierarchical breaking, O(3) -> O(2) -> SO(2) ->
nothing. The model naturally accounts for all the known lepton parameters and
yields various interesting predictions for others: (i) Neutrinos are nearly
degenerate, m_\nu \sim 0.1 eV; (ii) The solar neutrino problem is solved by the
MSW small mixing angle solution; (iii) The MNS mixing angle theta_{13} is
unobservably small, theta_{13} = O(10^{-5}).

</DOC>
<DOC>
<DOCNO> 121216 </DOCNO>
Superclustering of Faint Galaxies in the Field of a QSO Concentration at


  We report on a wide-area (48' x 9') imaging survey of faint galaxies in R and
I bands toward the 1338+27 field where an unusual concentration of five QSOs at
z\sim1.1, embedded in a larger-scale clustering of 23 QSOs, is known to exist.
Using a quite homogeneous galaxy catalog with a detection completeness limit of
I~23.5, we detect a significant clustering signature of faint red galaxies with
I > 21 and R-I > 1.2 over a scale extending to ~20h^{-1}_{50} Mpc. Close
examination of the color-magnitude diagram, the luminosity function, and the
angular correlation function indeed suggests that those galaxies are located at
z~1.1 and trace the underlying large-scale structure at that epoch, together
with the group of 5 QSOs. Since the whole extent of the cluster of 23 QSOs
(~70h^{-1}_{50} Mpc) is roughly similar to the local ``Great Wall'', the area
may contain a high-redshift counterpart of superclusters in the local universe.

</DOC>
<DOC>
<DOCNO> 70786 </DOCNO>
Droplet Formation in Quark-Gluon Plasma at Low Temperatures and High


  Considering the low-temperature ($T$) and high-baryon-number-density ($n_B$)
region of the QCD phase diagram, we present a model for the first-order phase
transition between the quark-gluon plasma (QGP) and the recently proposed
colour superconducting phase. We study nucleation of a droplet of the
superconducting phase within the metastable QGP gas. Numerical results for the
activation energy, radius and other physical parameters of the droplets, at
various temperatures, densities and gap parameters, are given. We have
estimated the latent heat of the phase transition. In the $T-n_B$ plane, we are
able to demarcate the region of the superconducting phase.

</DOC>
<DOC>
<DOCNO> 85207 </DOCNO>
Solution of Stationary and Axisymmetric Problem in General


  Physically admissible choice of the "essential" coordinates identified with
components of the metric tensor and co-moving frame of reference reduced to the
formulation of the stationary axisymmetric GR problem. Such nontraditional
approach allows to obtain new 4-parametric vacuum solution. In special static
case this solution becomes the set well-known GR exact solutions for degenerate
vacuum gravitational fields, in some special stationary case, after
transformations coincides with Kerr solution. In other special stationary case
the founded solution turn into modified NUT solution.

</DOC>
<DOC>
<DOCNO> 118113 </DOCNO>
Mass-loss induced instabilities in fast rotating stars


  To explain the origin of Herbig Ae/Be stars activity, it has been recently
proposed that strong mass-losses trigger rotational instabilities in the
envelope of fast rotating stars. The kinetic energy transferred to turbulent
motions would then be the energy source of the active phenomena observed in the
outer atmosphere of Herbig Ae/Be stars (Vigneron et al. 1990; Lignieres et al.
1996).
  In this paper, we present a one-dimensional model of angular momentum
transport which allows to estimate the degree of differential rotation induced
by mass-loss. Gradients of angular velocity are very close to - 2 \Omega / R
(\Omega being the surface rotation rate and R the stellar radius). For strong
mass-loss, this process occurs in a short time scale as compared to other
processes of angular momentum transport. Application of existing stability
criteria indicates that rotational instabilities should develop for fast
rotating star. Thus, in fast rotating stars with strong winds, shear
instabilities are expected to develop and to generate subphotospheric turbulent
motions. Albeit very simple, this model gives strong support to the assumption
made by Vigneron et al. 1990 and Lignieres et al. 1996.

</DOC>
<DOC>
<DOCNO> 121674 </DOCNO>
Performance characteristics of the new Keck Observatory echelle


  The Echelle Spectrograph and Imager (ESI) is a multipurpose instrument which
has been delivered by the Instrument Development Laboratory of Lick Observatory
for use at the Cassegrain focus of the Keck II telescope. ESI saw first light
on August 29, 1999. The optical performance of the instrument has been measured
using artificial calibration sources and starlight. Measurements of the average
image FWHM in echelle mode are 22 microns (0.22 arcseconds), 16 to 18 microns
(0.16 to 0.18 arcseconds) in broad band imaging mode, and comparable in the
low-dispersion prismatic mode (LDP). Images on the sky, under best seeing
conditions show FWHM sizes of 34 microns (0.34 arcseconds). Maximum
efficiencies are measured to be 30% for echelle and anticipated to be greater
than 38% for low dispersion prismatic mode including atmospheric, telescope and
detector losses. In this paper we describe the instrument and its
specifications. We discuss the testing that led to the above conclusions.

</DOC>
<DOC>
<DOCNO> 71137 </DOCNO>
Vacuum Instability in Anomaly Mediation Models with Massive Neutrinos


  We study the vacuum stability in the anomaly mediated supersymmetry (SUSY)
breaking models with massive neutrinos. It is shown that, because of the
seesaw-induced mass terms for neutrinos, the true vacuum has a large negative
cosmological constant provided that the vacuum where we now live has an
(almost) vanishing cosmological constant. Although the quantum transition into
the true vacuum from our false vacuum is highly suppressed, the thermal
transition at high temperatures may not be neglected because of the thermal
excitations. However, we find that the thermal transition is, in fact,
negligibly small and hence the anomaly mediation models are cosmologically
safe. Thus, we conclude that the reheating temperature T_R could be very high
(e.g. T_R >> 10^10 GeV) in the anomaly mediation models even with the
seesaw-induced mass terms for neutrinos.

</DOC>
<DOC>
<DOCNO> 120792 </DOCNO>
The distribution of shock waves in driven supersonic turbulence


  Supersonic turbulence generates distributions of shock waves. Here, we
analyse the shock waves in three-dimensional numerical simulations of uniformly
driven supersonic turbulence, with and without magnetohydrodynamics and
self-gravity. We can identify the nature of the turbulence by measuring the
distribution of the shock strengths.
  We find that uniformly driven turbulence possesses a power law distribution
of fast shocks with the number of shocks inversely proportional to the square
root of the shock jump speed. A tail of high speed shocks steeper than Gaussian
results from the random superposition of driving waves which decay rapidly. The
energy is dissipated by a small range of fast shocks. These results contrast
with the exponential distribution and slow shock dissipation associated with
decaying turbulence.
  A strong magnetic field enhances the shock number transverse to the field
direction at the expense of parallel shocks. A simulation with self-gravity
demonstrates the development of a number of highly dissipative accretion
shocks. Finally, we examine the dynamics to demonstrate how the power-law
behaviour arises.

</DOC>
<DOC>
<DOCNO> 13699 </DOCNO>
Dispersion of the neutron resonance in cuprate superconductors


  We argue that recently measured downward dispersion of the neutron resonance
peak in cuprate superconductors is naturally explained if the resonance is
viewed as a spin-1 collective mode in a d-wave superconductor. The reduction of
the resonant frequency away from the antiferromagnetic wave vector is a direct
consequence of the momentum dependence of the d-wave superconducting gap. When
the magnetic correlation length becomes large, the dispersion should become
magnon-like, i.e., curve upwards from (pi,pi).

</DOC>
<DOC>
<DOCNO> 12529 </DOCNO>
Convective instability on a crystal surface


  The distinction between absolute and convective instabilities is well known
in the context of hydrodynamics and plasma physics. In this Letter, we examine
an epitaxial crystal growth model from this point of view and show that a
strain-induced step bunching instability can be convective. Using analytic
stability theory and numerical simulations, we study the response of the
crystal surface to an inhomogeneous deposition flux that launches impulsive and
time-periodic perturbations to a uniform array of steps. The results suggest a
new approach to morphological patterning.

</DOC>
<DOC>
<DOCNO> 121474 </DOCNO>
Light Element Nucleosynthesis


  An introductory review of the early evolution of the Universe relevant to the
primordial synthesis of the light nuclides deuterium, helium-3, helium-4 and
lithium-7. The predictions of the element abundances in the "standard", hot,
big bang cosmological model (SBBN) are described. After descriptions of the
evolution of the primordial abundances from "there and then" to "here and now",
the SBBN predictions are compared to current observational data. The
implications for the standard model and for physics beyond the standard model
are discussed.

</DOC>
<DOC>
<DOCNO> 120225 </DOCNO>
Faint Radio Sources and Star Formation History


  The centimeter-wave luminosity of local radio galaxies correlates well with
their star formation rate. We extend this correlation to surveys of
high-redshift radio sources to estimate the global star formation history. The
star formation rate found from radio observations needs no correction for dust
obscuration, unlike the values calculated from optical and ultraviolet data.
Three deep radio surveys have provided catalogs of sources with nearly complete
optical identifications and nearly 60% complete spectroscopic redshifts: the
Hubble Deep Field and Flanking Fields at 12h+62d, the SSA13 field at 13h+42d,
and the V15 field at 14h+52d. We use the redshift distribution of these radio
sources to constrain the evolution of their luminosity function. The epoch
dependent luminosity function is then used to estimate the evolving global star
formation density. At redshifts less than one, our calculated star formation
rates are significantly larger than even the dust-corrected optically-selected
star formation rates; however, we confirm the rapid rise from z=0 to z=1 seen
in those surveys.

</DOC>
<DOC>
<DOCNO> 72201 </DOCNO>
Can Supersymmetric Loops Correct the Fermion Mass Relations in SU(5)?


  We investigate three different possibilities for improving the fermion mass
relations that arise in grand unified theories (GUTs). Each scenario relies on
supersymmetric loop effects alone, without modifying the naive Yukawa
unification. First, we consider A-terms that follow the usual proportionality
condition. In this case SUSY effects can improve the mass relations, but not
completely. Interestingly, imposing Yukawa coupling unification for two
families greatly constrains the range of parameters in the MSSM. Secondly, we
employ a new ansatz for the tri-linear A-terms that satisfies all experimental
and vacuum stability bounds, and can successfully modify the mass relations.
Finally, we investigate the use of general (non-proportional) A-terms, with
large off-diagonal entries. In this case flavor changing neutral current (FCNC)
data present an important constraint. We do not pretend to present a complete,
motivated theory of fermion masses. Rather this paper can be viewed as an
existence proof, serving to show that Yukawa coupling unification can occur
even within the framework of minimal GUTs.

</DOC>
<DOC>
<DOCNO> 9914 </DOCNO>
Magnetoelastic coupling in epitaxial magnetic films: An ab-initio study


  A method is developed which allows to determine the first-order and the
second-order magnetoelastic coefficients of a magnetic bulk material from the
ab-initio calculation of the magnetocrystalline anisotropy energy as function
of a prestrain. Excplicit results are given for bcc Fe, and they agree well
with experimental data obtained from the magnetostrictive stress measurements
for epitaxial Fe films.

</DOC>
<DOC>
<DOCNO> 118745 </DOCNO>
Submillimeter and Far-InfraRed Experiment (SAFIRE): A PI class


  SAFIRE is a versatile imaging Fabry-Perot spectrograph covering 145 to 655
microns, with spectral resolving powers ranging over 5-10,000. Selected as a
"PI" instrument for the airborne Stratospheric Observatory for Infrared
Astronomy (SOFIA), SAFIRE will apply two-dimensional pop-up bolometer arrays to
provide background-limited imaging spectrometry. Superconducting transition
edge bolometers and SQUID multiplexers are being developed for these detectors.
SAFIRE is expected to be a "First Light" instrument, useable during the initial
SOFIA operations. Although a PI instrument rather than a "Facility Class"
science instrument, it will be highly integrated with the standard SOFIA
planning, observation, and data analysis tools.

</DOC>
<DOC>
<DOCNO> 67969 </DOCNO>
Signal-to-noise ratio for a stochastic background of massive relic


  We estimate the signal-to-noise ratio for two gravitational detectors
interacting with a stochastic background of massive scalar waves. We find that
the present experimental level of sensitivity could be already enough to detect
a signal from a light but non-relativistic component of dark matter, even if
the coupling is weak enough to exclude observable deviations from standard
gravitational interactions, provided the mass is not too far from the
sensitivity and overlapping band of the two detectors.

</DOC>
<DOC>
<DOCNO> 71727 </DOCNO>
A Model of Elementary Particle Interactions


  There is a second kind of light which does not interact with our electrons.
However it interacts with some of our protons (p) and some of our neutrons (n)
which are both of two kinds: protons (p, p`), neutrons (n`, n) differing in the
two kinds of charges (Q1, Q2) associated with the two kinds of light. p [p`]
and n` [n] have (Q1, Q2) values equal to (1, 1) [(1, 0)] and (0, 0) [(0, 1)]
respectively. There is also a second kind of electron (Q2 =1, Q1= 0), equal in
mass to our electron (Q1 = -1, Q2= 0), which does not interact with our (the
first) kind of light. Three major scenarios S1, S2 and X4 arise. In S1, matter
in the solar system on large scales is predominantly neutralized in both kinds
of charges and the weak forces of attraction among the sun and planets are due
to a fundamental force of nature. However in this scenario we must postulate
that human consciousness is locked on to chemical reactions in the retina
involving the first kind of light and the first kind of electrons only. It is
oblivious to the simultaneous parallel chemical reactions governed by a
chemistry which is based on the second kind of light and the second kind of
anti-electrons and involves the same physical atoms manifesting different
atomic numbers Z` (= Q2). In scenario S2, matter in the solar system on large
scales is predominantly neutralized in the first kind of charge only. In this
scenario human consciousness is not restricted in its awareness to a narrowly
>....... continued

</DOC>
<DOC>
<DOCNO> 117767 </DOCNO>
Transient X--Ray Sources Observed with the Rxte All-Sky Monitor after


  We present light curves of a sample of "transient" sources observed with the
All-Sky Monitor (ASM) of the Rossi X-ray Timing Explorer (RXTE). The light
curves extend over 3.5 years. They are presented in three groups: six
neutron-star systems, eight black-hole-candidate systems, and an additional
diverse set of six objects that are either transient sources (in the sense of
usually being undetectable) or persistent sources showing transient behavior.
The outburst profiles of these sources show reproducible characteristics within
one source and from source to source, as well as large variations. These
profiles together with the profiles of the hardness ratios from the ASM are a
valuable resource for the understanding of accretion instabilities. We
summarize briefly some recent work by observers on these somewhat arbitrarily
selected sources.

</DOC>
<DOC>
<DOCNO> 99439 </DOCNO>
Applications of another characterization of betaN\N


  Steprans provided a characterization of betaN\N in the aleph_2-Cohen model
that is much in the spirit of Parovicenko's characterization of this space
under CH. A variety of the topological results established in the Cohen model
can be deduced directly from the properties of betaN\N or P(N)/fin that feature
in Steprans' result.

</DOC>
<DOC>
<DOCNO> 117333 </DOCNO>
Method for Precision Test of Fine Structure Constant Variation with


  A new method for examining the possible space-time variation of the fine
structure constant ($\alpha$) is proposed. The technique uses a relatively
simple measurement with an optical resonator to compare atom-stabilized optical
frequency references. This method does not require that the exact frequency of
each reference be measured, and has the potential to yield more than a
1000-fold improvement in experimental sensitivity to changes in $\alpha$. A
specific realization of an experiment using this method is discussed which can
approach the precision of ${\dot\alpha/\alpha}\sim10^{-18}/\tau$, where $\tau$
is the measurement time. Moreover, for this specific realization, a measurement
of ${\dot\alpha/\alpha}\sim10^{-15}/{\rm yr}$ as a near-term goal is realistic.

</DOC>
<DOC>
<DOCNO> 178728 </DOCNO>
Kaon photoproduction on the nucleon: overview of some applications


  Some applications of the elementary kaon photoproduction process are
discussed: the investigation of missing resonances in the p(gamma,K+)Lambda
channel, the role of the P_{13}(1720) state in the p(gamma,K0)Sigma+ channel,
and the calculation of the Gerasimov-Drell-Hearn sum rule. For the latter, we
present an extension of our previous study to higher energies.

</DOC>
<DOC>
<DOCNO> 13210 </DOCNO>
Entropic effects on the Size Evolution of Cluster Structure


  We show that the vibrational entropy can play a crucial role in determining
the equilibrium structure of clusters by constructing structural phase diagrams
showing how the structure depends upon both size and temperature. These phase
diagrams are obtained for example rare gas and metal clusters.

</DOC>
<DOC>
<DOCNO> 101330 </DOCNO>
Super Chern Simons Theory and Flat Super Connections on a Torus


  We study the moduli space of a super Chern-Simons theory on a manifold with
the topology ${\bf R}\times \S$, where $\S$ is a compact surface. The moduli
space is that of flat super connections modulo gauge transformations on $\S$,
and we study in detail the case when $\S$ is atorus and the supergroup is
$OSp(m|2n)$. The bosonic moduli space is determined by the flat connections for
the maximal bosonic subgroup $O(m)\times Sp(2n)$, while the fermionic moduli
appear only for special parts of the bosonic moduli space, which are determined
by a vanishing determinant of a matrix associated to the bosonic part of the
holonomy. If the CS supergroup is the exponential of a super Lie algebra, the
fermionic moduli appear only for the bosonic holonomies whose generators have
zero determinant in the fermion-fermion block of the super-adjoint
representation. A natural symplectic structure on the moduli space is induced
by the super Chern-Simons theory and it is determined by the Poisson bracket
algebra of the holonomies. We show that the symplectic structure of homogenous
connections is useful for understanding the properties of the moduli space and
the holonomy algebra, and we illustrate this on the example of the $OSp(1|2)$
supergroup.

</DOC>
<DOC>
<DOCNO> 118223 </DOCNO>
Formation of the optical spectra of the coolest M- and L-dwarfs and


  Theoretical aspects of modeling of spectra of late M- and L-dwarfs are
discussed. We show, that the processes of formation of spectra of M- and
L-dwarfs are basically different. Instead of the case of M-dwarfs, atoms of Ti
and V should be depleted into grains in the atmospheres of L-dwarfs. Overall
shape of the L-dwarf spectra is governed by the K I + Na I resonance line wings
of the huge strength. To fit lithium lines observed in spectra of the coolest
dwarfs we used two additional suggestions: a) there are some EXTRA depletions
of molecular species absorbed in the optical spectra of L-dwarfs; b) there may
be (a few?) additional (``dusty''?) opacity sources in their atmospheres.
Problems of lithium line formation and the ``natural'' limitation of their use
for the ``lithium test'' for the case of L-dwarfs are considered.

</DOC>
<DOC>
<DOCNO> 11981 </DOCNO>
The Phases of QCD in Heavy Ion Collisions and Compact Stars


  I review arguments for the existence of a critical point in the QCD phase
diagram as a function of temperature and baryon chemical potential. I describe
how heavy ion collision experiments at the SPS and RHIC can discover the
tell-tale signatures of such a critical point, thus mapping this region of the
QCD phase diagram. I then review the phenomena expected in cold dense quark
matter: color superconductivity and color-flavor locking. I close with a
snapshot of ongoing explorations of the implications of recent developments in
our understanding of cold dense quark matter for the physics of compact stars.

</DOC>
<DOC>
<DOCNO> 122294 </DOCNO>
Precessing collimated outflows in the planetary nebula IC 4846


  We present [N II] and H-alpha images and high resolution long-slit spectra of
the planetary nebula IC 4846, which reveal, for the first time, its complex
structure and the existence of collimated outflows. The object consists of a
moderately elongated shell, two (and probably three) pairs of collimated
bipolar outflows at different orientations, and an attached circular shell. One
of the collimated pairs is constituted by two curved, extended filaments whose
properties indicate a high velocity, bipolar precessing jet. A difference of
\~10 km/s is found between the systemic velocity of the precessing jets and the
centroid velocity of the nebula, as recently report for Hu 2-1. We propose that
this difference is due to orbital motion of the ejection source in a binary
central star. The orbital separation and period estimates for the binary star
are less than or equal to 30 AU and 100 yr, respectively. These are similar to
those previously estimated for Hu 2-1, linking the central stars of both
planetary nebulae to interacting binaries. Extraordinary similarities also
exist between IC 4846 and the bewildering planetary nebula NGC 6543, suggesting
a similar formation history for both objects.

</DOC>
<DOC>
<DOCNO> 40368 </DOCNO>
DIRC, the Particle Identification System for BABAR


  The DIRC, a novel type of Cherenkov ring imaging device, is the primary
hadronic particle identification system for the BABAR detector at the
asymmetric B-factory, PEP-II at SLAC. BABAR began taking data with colliding
beams mode in late spring 1999. This paper describes the performance of the
DIRC during the first 16 months of operation.

</DOC>
<DOC>
<DOCNO> 9456 </DOCNO>
The spatial correlations in the velocities arising from a random


  This paper is devoted to a statistical analysis of the velocity fluctuations
arising from a random distribution of point vortices in two-dimensional
turbulence. Exact results are derived for the correlations in the velocities
occurring at two points separated by an arbitrary distance. We find that the
spatial correlation function decays extremely slowly with the distance. We
discuss the analogy with the statistics of the gravitational field in stellar
systems.

</DOC>
<DOC>
<DOCNO> 102695 </DOCNO>
Wavelet analysis as a p-adic spectral analysis


  New orthonormal basis of eigenfunctions for the Vladimirov operator of p-adic
fractional derivation is constructed. The map of p-adic numbers onto real
numbers (p-adic change of variables) is considered. This map (for p=2) provides
an equivalence between the constructed basis of eigenfunctions of the
Vladimirov operator and the wavelet basis in L^2(R) generated from the Haar
wavelet. This means that the wavelet analysis can be considered as a p-adic
spectral analysis.

</DOC>
<DOC>
<DOCNO> 8783 </DOCNO>
A critical review of techniques for Term Structure analysis


  Fixed income markets share many features with the equity markets. However
there are significant differences as well and many attempts have been done in
the past to develop specific tools which describe (and possibly forecasts) the
behavior of such markets.
  For instance, a correct pricing of fixed income securities with fixed cache
flows requires the knowledge of the {\it term structure} of interest rates. A
number of techniques have been proposed for estimating and interpreting the
term structure, yet solid theoretical foundations and a comparative assessment
of the results produced by these techniques are not available.
  In this paper we define the fundamental concepts with a mathematical
terminology. Besides that, we report about an extensive set of experiments
whose scope is to point out the strong and weak points of the most widely used
approaches in this field.

</DOC>
<DOC>
<DOCNO> 68755 </DOCNO>
Baryon Spectrum in the Large N_c Limit


  We present a model-independent analysis of the mass spectrum of nonstrange
L=1 baryons in large N_c QCD. The 1/N_c expansion is used to select and order a
basis of effective operators that spans the nine observables (seven masses and
two mixing angles). Comparison to the data provides support for the validity of
the 1/N_c expansion, but also reveals that only a few nontrivial operators are
strongly preferred. We show that our results have a consistent interpretation
in a constituent quark model with pseudoscalar meson exchange interactions.

</DOC>
<DOC>
<DOCNO> 69656 </DOCNO>
Dimensionally regulated one-loop box scalar integrals with massless


  Using the Feynman parameter method, we have calculated in an elegant manner a
set of one$-$loop box scalar integrals with massless internal lines, but
containing 0, 1, 2, or 3 external massive lines. To treat IR divergences (both
soft and collinear), the dimensional regularization method has been employed.
The results for these integrals, which appear in the process of evaluating
one$-$loop $(N\ge 5)-$point integrals and in subdiagrams in QCD loop
calculations, have been obtained for arbitrary values of the relevant kinematic
variables and presented in a simple and compact form.

</DOC>
<DOC>
<DOCNO> 99765 </DOCNO>
Some real and unreal enumerative geometry for flag manifolds


  We present a general method for constructing real solutions to some problems
in enumerative geometry which gives lower bounds on the maximum number of real
solutions. We apply this method to show that two new classes of enumerative
geometric problems on flag manifolds may have all their solutions be real and
modify this method to show that another class may have no real solutions, which
is a new phenomenon. This method originated in a numerical homotopy
continuation algorithm adapted to the special Schubert calculus on
Grassmannians and in principle gives optimal numerical homotopy algorithms for
finding explicit solutions to these other enumerative problems.

</DOC>
<DOC>
<DOCNO> 170185 </DOCNO>
Experimental test of non-local quantum correlation in relativistic


  We report on a new kind of experimental investigations of the tension between
quantum nonlocally and relativity. Entangled photons are sent via an optical
fiber network to two villages near Geneva, separated by more than 10 km where
they are analyzed by interferometers. The photon pair source is set as
precisely as possible in the center so that the two photons arrive at the
detectors within a time interval of less than 5 ps (corresponding to a path
length difference of less than 1 mm). One detector is set in motion so that
both detectors, each in its own inertial reference frame, are first to do the
measurement! The data always reproduces the quantum correlations, making it
thus more difficult to consider the projection postulate as a compact
description of real collapses of the wave-function.

</DOC>
<DOC>
<DOCNO> 121278 </DOCNO>
X-Ray Flux Decrease of the Accretion-Powered Millisecond Pulsar SAX


  The accretion-powered millisecond X-ray pulsar, SAX J1808.4-3658, was
observed in quiescence with ASCA in September 1999. We detected a dim X-ray
source in the SIS data at the position consistent to SAX J1808.4-3658. The
source count rate was (1.1+-0.4)x10E-3 cts/s (0.5-5 keV) for a single SIS,
which corresponds to (3+-1)x10E-14 ergs/s/cmE2 if a power law energy spectrum
of photon index 2 with low-energy absorption corresponding to a hydrogen column
density of 1.3x10E21 cmE-2 is assumed. The statistical quality of the data was
insufficient to constrain the energy spectrum or to detect the 401 Hz coherent
pulsation. We compare the data with the BeppoSAX observation also made during
the quiescent state, and find that the X-ray flux measured by ASCA is at least
a factor of 4 smaller than that measured by BeppoSAX. We discuss the possible
X-ray emission mechanisms that could explain the flux change, including the
radio pulsar and the radio pulsar shock emission.

</DOC>
<DOC>
<DOCNO> 116613 </DOCNO>
Kinetic Slip Condition, van der Waals Forces, and Dynamic Contact Angle


  The profiles of a spreading wetting film are computed taking into account
intermolecular forces and introducing a kinetic slip condition at a molecular
cut-off distance. This eliminates the stress singularity, so that both "true"
and "visible" contact angles are defined unequivocally. The "true" contact
angle at the cut-off distance depends on the slip length as well as on the edge
propagation speed, but not on gravity or asymptotic inclination angle. These
macroscopic factors influence, however, the "visible" contact angle observed in
the interval where the actual film profile departs from the intermediate
asymptotic curve.

</DOC>
<DOC>
<DOCNO> 122216 </DOCNO>
Anisotropic inverse Compton scattering in radio galaxies and particle


  In this talk we briefly review the inverse Compton (IC) scattering of nuclear
photons in the lobes of radio galaxies and quasars. We concentrate on the
possibility to test this model with the Chandra observatory and to constrain
the electron energy distribution by measuring the X-ray fluxes produced by this
effect. We also discuss the evidence for IC scattering of nuclear photons in
the powerful radio galaxies.

</DOC>
<DOC>
<DOCNO> 40103 </DOCNO>
Measurement of the Decay Amplitudes of B0 --> J/psi K* and B0s --> J/psi


  A full angular analysis has been performed for the pseudo-scalar to
vector-vector decays, B0 --> J/psi K* and B_s --> J/psi phi, to determine the
amplitudes for decays with parity-even longitudinal and transverse polarization
and parity-odd transverse polarization. The measurements are based on 190 B0
candidates and 40 B_s candidates collected from a data set corresponding to 89
inverse pb of pbarp collisions at root(s) = 1.8 TeV at the Fermilab Tevatron.
In both decays the decay amplitude for longitudinal polarization dominates and
the parity-odd amplitude is found to be small.

</DOC>
<DOC>
<DOCNO> 116998 </DOCNO>
Electro-Optic Sampling of Transient Fields from the passage of


  When a relativistic electron bunch traverses a structure, strong electric
fields are induced in its wake. We present measurements of the electric field
as a function of time as measured at a fixed location in the beam line. For a
12 nC bunch of duration 4.2 ps FWHM, the peak field is measured >0.5 MV/m. Time
resolution of ~5 ps is achieved using electro-optic sampling with a lithium
tantalate (LiTaO_3) crystal and a short-pulse infrared laser synchronized to
the beam. We present measurements under several different experimental
conditions and discuss the influence of mode excitation in the structure.

</DOC>
<DOC>
<DOCNO> 170242 </DOCNO>
Effect of classically forbidden momenta in one dimensional quantum


  The transmitted wave that results from a collision of a wave packet which is
initially to the left of a potential barrier depends in general on the
amplitudes of negative momenta of the initial state. The exact form of this
dependence is shown and the importance of this classically forbidden effect is
illustrated with numerical examples. Special care is taken to account properly
for bound states.

</DOC>
<DOC>
<DOCNO> 8476 </DOCNO>
The ground state of Sr3Ru2O7 revisited; Fermi liquid close to a


  We show that single-crystalline Sr3Ru2O7 grown by a floating-zone technique
is an isotropic paramagnet and a quasi-two dimensional metal as spin-triplet
superconducting Sr2RuO4 is. The ground state is Fermi liquid with very low
residual resistivity (3 micro ohm cm for in-plane currents) and a nearly
ferromagnetic metal with the largest Wilson ratio Rw>10 among paramagnets so
far. This contrasts with the ferromagnetic order at Tc=104 K reported on single
crystals grown by a flux method [Cao et al., Phys. Rev. B 55, R672 (1997)]. We
have also found a dramatic changeover from paramagnetism to ferromagnetism
under applied pressure. This suggests the existence of a substantial
ferromagnetic instability on the verge of a quantum phase transition in the
Fermi liquid state.

</DOC>
<DOC>
<DOCNO> 174544 </DOCNO>
A New Measurement of the Energy Dependence of Nuclear Transparency for


  We present a new measurement of the energy dependence of nuclear transparency
from AGS experiment E850, performed using the EVA solenoidal spectrometer,
upgraded since 1995. Using a secondary beam from the AGS accelerator, we
simultaneously measured $pp$ elastic scattering from hydrogen and $(p,2p)$
quasi-elastic scattering in carbon at incoming momenta of 5.9, 8.0, 9.0, 11.7
and 14.4 GeV/c. This incident momentum range corresponds to a $Q^{2}$ region
between 4.8 and 12.7 (GeV/c)$^{2}$. The detector allowed us to do a complete
kinematic analysis for the center-of-mass polar angles in the range
$85^{\circ}-90^{\circ}$. We report on the measured variation of the nuclear
transparency with energy and compare the new results with previous
measurements.

</DOC>
<DOC>
<DOCNO> 100626 </DOCNO>
Witt groups and torsion Picard groups of smooth real curves


  The Witt group of a smooth curve over a real closed field is explicitely
calculated. The method uses a comparison theorem between the graded Witt group
and the etale cohomology groups. In the second part of the paper, the torsion
Picard group of a smooth real curve is also computed. The calculation depends
on a new invariant introduced here. We prove that several problems of real
algebraic geometry are related to this invariant.

</DOC>
<DOC>
<DOCNO> 116878 </DOCNO>
Wire Scanners for Small Emittance Beam Measurement in Atf


  The wire scanners are used for a measurement of the very small beam size and
the emittance in Accelerator Test Facility (ATF). They are installed in the
extraction beam line of ATF damping ring. The extracted beam emittance are
ex=1.3x10-9 m.rad, ey=1.7x10-11 m.rad with 2x109 electrons/bunch intensity and
1.3GeV energy. The wire scanners scan the beam by a tungsten wire with beam
repetition 0.78Hz. The scanning speed is, however, very slow(~500um/sec). Since
the extracted beam is quite stable by using the double kicker system, precision
of the size measurement is less than 2um for 50 - 150um horizontal beam size
and 0.3um for 8 - 16um vertical beam size. The detail of the system and the
performance are described.

</DOC>
<DOC>
<DOCNO> 67705 </DOCNO>
On determining CKM angles alpha and beta


  Because the Bd -> J/psi Ks asymmetry determines only sin(2 beta), a discrete
ambiguity in the true value of beta remains. This note reviews how the
ambiguity can be removed. Extractions of the CKM angle alpha are discussed
next. Some of the methods require very large data samples and will not be
feasible in the near future. In the near future, semi-inclusive CP-violating
searches could be undertaken, which are reviewed last.

</DOC>
<DOC>
<DOCNO> 9701 </DOCNO>
A study of disordered systems with gain: Stochastic Amplification


  A study of statistics of transmission and reflection from a random medium
with stochastic amplification as opposed to coherent amplification is
presented. It is found that the transmission coefficient $t$, for sample length
$L$ less than the critical length $L_c$ grows exponentially with $L$. In the
limit $L \to \infty$ transmission decays exponentially as $\avg{lnt} = -L/\xi$
where $\xi$ is the localization length. In this limit reflection coefficient
$r$ saturates to a fixed value which shows a monotonic increase as a function
of strength of amplification $\alpha$. The stationary distribution of
super-reflection coefficient agrees well with the analytical results obtained
within the random phase approximation (RPA). Our model also exhibits the well
known duality between absorption and amplification. We emphasize the major
differences between coherent amplification and stochastic amplification
where-ever appropriate.

</DOC>
<DOC>
<DOCNO> 72312 </DOCNO>
Implications of a possible 115 GeV supersymmetric Higgs boson on


  We show that a supersymmetric neutral Higgs boson with a mass of about 115
GeV and with the other prerequisites required by the LEP Higgs events would be
compatible with the detection of relic neutralinos in current set-ups for WIMP
direct search. Thus this putative Higgs would fit remarkably well in an
interpretation in terms of relic neutralinos of the annual-modulation effect
recently measured in a WIMP direct experiment. We also show that the
cosmological abundance of the relevant neutralinos reaches values of
cosmological interest.

</DOC>
<DOC>
<DOCNO> 123302 </DOCNO>
Applications of Indirect Imaging techniques in X-ray binaries


  A review is given on aspects of indirect imaging techniques in X-ray binaries
which are used as diagnostics tools for probing the X-ray dominated accretion
disc physics. These techniques utilize observed properties such as the emission
line profile variability, the time delays between simultaneous optical/X-ray
light curves curves, the light curves of eclipsing systems and the pulsed
emission from the compact object in order to reconstruct the accretion disc's
line emissivity (Doppler tomography), the irradiated disc and heated secondary
(echo mapping), the outer disc structure (modified eclipse mapping) and the
accreting regions onto the compact object, respectively.

</DOC>
<DOC>
<DOCNO> 118573 </DOCNO>
Weak Lensing by Large-Scale Structure: A Dark Matter Halo Approach


  Weak gravitational lensing observations probe the spectrum and evolution of
density fluctuations and the cosmological parameters which govern them but are
currently limited to small fields and subject to selection biases. We show how
the expected signal from large-scale structure arises from the contributions
from and correlations between individual halos. We determine the convergence
power spectrum as a function of the maximum halo mass and so provide the means
to interpret results from surveys that lack high mass halos either through
selection criteria or small fields. Since shot noise from rare massive halos is
mainly responsible for the sample variance below 10', our method should aid our
ability to extract cosmological information from small fields.

</DOC>
<DOC>
<DOCNO> 11570 </DOCNO>
Thermo-refractive noise in gravitational wave antennae


  Thermodynamical fluctuations of temperature in mirrors of gravitational wave
antennae may be transformed into additional noise not only through thermal
expansion coefficient but also through temperature dependence of refraction
index. The intensity of this noise is comparable with other known noises and
must be taken into account in future steps of the antennas.

</DOC>
<DOC>
<DOCNO> 39778 </DOCNO>
Study of RPC gas mixtures for the ARGO-YBJ experiment


  The ARGO-YBJ experiment consists of a RPC carpet to be operated at the
Yangbajing laboratory (Tibet, P.R. China), 4300 m a.s.l., and devoted to the
detection of showers initiated by photon primaries in the energy range 100 GeV
- 20 TeV. The measurement technique, namely the timing on the shower front with
a few tens of particles, requires RPC operation with 1 ns time resolution, low
strip multiplicity, high efficiency and low single counting rate. We have
tested RPCs with many gas mixtures, at sea level, in order to optimize these
parameters. The results of this study are reported.

</DOC>
<DOC>
<DOCNO> 10872 </DOCNO>
Superconducting properties of [BaCuO_x]_2/[CaCuO_2]_n artificial


  The electrical transport properties of [BaCuO_x]_2/[CaCuO_2]_n
(CBCCO-2xn)underdoped high temperature superconducting superlattices grown by
Pulsed Laser Deposition have been investigated. Starting from the optimally
doped CBCCO-2x2 superlattice, having three CuO_2 planes and T_c around 80 K, we
have systematically increased the number n up to 15 moving toward the
underdoped region and hence decreasing T_c. For n>11 the artificial structures
are no longer superconducting, as expected, for a uniformly distributed charge
carriers density inside the conducting block layer. The sheet resistance of
such artificial structures (n nearly equal to 11) turns out to be quite
temperature independent and close to the 2D quantum resistance 26 kOhm. A
further increase of the number of CuO_2 planes results in an insulator-type
dependence of R(T) in the wide range of temperatures from room temperature to 1
K. The value of the sheet resistance separating the Superconducting and the
Insulating regimes supports the fermionic scenario of the
Superconductor-Insulator transition in these systems.

</DOC>
<DOC>
<DOCNO> 12265 </DOCNO>
Spin-Isospin Model of NaV_2O_5


  We argue that in the quarter-filled ladder compound NaV_2O_5 the
quasi-one-dimensional spin system is strongly coupled to a low-energy
antiferroelectric mode of the excitonic type. This mode results from the
interplay between the electron hopping along the rungs of the vanadium two-leg
ladders and the Coulomb repulsion between electrons. The charge ordering
observed in sodium vanadate at T_c = 34K corresponds to the softening of the
antiferroelectric mode. We consider the spin-isospin model, which describes the
spin and low-energy charge degrees of freedom in sodium vanadate. Within this
model we explain the observed anomalous temperature-dependence of the
dielectric susceptibility at T_c and the midinfrared absorption continuum. We
identify the broad structure in the low-energy optical absorption spectrum of
NaV_2O_5 with the continuum formed by two spinons and one low-energy charge
excitation.

</DOC>
<DOC>
<DOCNO> 150537 </DOCNO>
The IR/UV Connection in the Non-Commutative Gauge Theories


  Quantum field theory on non-commutative spaces does not enjoy the usual
ultraviolet-infrared decoupling that forms the basis for conventional
renormalization. The high momentum contributions to loop integrations can lead
to unfamiliar long distance behavior which can potentially undermine naive
expectations for the IR behavior of the theory. These "anomalies" involve
non-analytic behavior in the noncommutativity parameter Theta making the limit
Theta goes to zero singular.
  In this paper we will analyze such effects in the one loop approximation to
gauge theories on non-commutative space. We will see that contrary to
expectations poles in Theta do occur and lead to large discrepancies between
the expected and actual infrared behavior. We find that poles in Theta are
absent in supersymmetric theories. The "anomalies" are generally still present,
but only at the logarithmic level. A notable exception is non-commutative super
Yang Mills theory with 16 real supercharges in which anomalous effects seem to
be absent altogether.

</DOC>
<DOC>
<DOCNO> 69527 </DOCNO>
Theoretical Overview of CP Violation in B-Meson Decay


  After a brief look at CP violation in kaon decays, a short overview of CP
violation in the $B$-meson system and of strategies to determine the angles of
the unitarity triangles of the CKM matrix is given. Both general aspects and
some recent developments are discussed, including $B_c^\pm\to D^\pm_s D$ and
$B\to\pi K$ decays, as well as the $B_d\to\pi^+\pi^-$, $B_s\to K^+K^-$ system.

</DOC>
<DOC>
<DOCNO> 122890 </DOCNO>
Supernova Science with an Advanced Compton Telescope


  Gamma-ray line emission is a direct probe of the nucleosynthesis that occurs
in Type Ia supernovae. In this work we describe the wealth of information
obtainable from observations of this emission. Advanced Compton telescope
designs are being studied by the Naval Research Laboratory, with the goal being
the construction of a telescope which would be capable of detecting SNe Ia to
distances in excess of 100 Mpc. We describe the instrument capabilities and the
design issues that are being addressed. We assume a SN Ia rate and quantify the
frequency at which an advanced Compton telescope could detect, discriminate
between, and diagnose Type Ia supernovae. From these estimates, we argue that
an advanced Compton telescope would be a powerful astrophysical tool.

</DOC>
<DOC>
<DOCNO> 71152 </DOCNO>
Do "isolated" planetary mass objects orbit mirror stars?


  We propose that the ``isolated'' planetary mass objects observed by Zapatero
Osorio et al in the $\sigma$ Orionis cluster might actually be in orbit around
invisible stellar mass companions such as mirror stars. Mirror matter is
expected to exist if parity is an unbroken symmetry of nature. Future
observations can test this idea by looking for a periodic Doppler shift in the
radiation emitted by the planets. The fact that the observations show an
inverse dependence between the abundance of the these objects and their mass
may argue in favour of the mirror matter hypothesis.

</DOC>
<DOC>
<DOCNO> 150950 </DOCNO>
Wilson Loops in the Higgs Phase of Large N Field Theories on the


  We study the quark-antiquark interaction in the large N limit of the
superconformal field theory on D-3branes at a Calabi-Yau conical singularity.
We compute the Wilson loop in the AdS_5xT^{11} supergravity background for the
SU(2N)x SU(2N) theory. We also calculate the Wilson loop for the Higgs phase
where the gauge group is broken to SU(N)x SU(N)x SU_D(N). This corresponds to a
two center configuration with some of the branes at the singularity and the
rest of them at a smooth point. The calculation exhibits the expected Coulomb
dependence for the interaction. The angular distribution of the BPS states is
different than the one for a spherical horizon.

</DOC>
<DOC>
<DOCNO> 13230 </DOCNO>
Hall effect in the cuprates: the role of forward scattering on


  We solve the Boltzmann equation for electrons moving in a two-dimensional
plane of square symmetry in the presence of a transverse magnetic field. We
assume that there are two sources of scattering: a large momentum-independent
scattering on a collective mode of the electron system, and a smaller
momentum-dependent forward scattering on impurities. We show that the effect of
impurities on the longitudinal and Hall conductivities is of the same order of
magnitude.

</DOC>
<DOC>
<DOCNO> 120250 </DOCNO>
On the cosmological distance and redshift between any two objects


  We discuss the problem of how to calculate the distance between two
cosmological objects given their redshifts and angular separation on the sky.
Although of a fundamental nature, this problem and its solution seem to lack a
detailed description in the literature. We present a new variant of its
solution and quantitatively assess the most commonly used approximation.

</DOC>
<DOC>
<DOCNO> 68402 </DOCNO>
Vacuum structure of a modified MIT Bag


  An alternative to introducing and subsequently renormalizing classical
parameters in the expression for the vacuum energy of the MIT bag for quarks is
proposed in the massless case by appealing to the QCD trace anomaly and scale
separation due to asymptotic freedom. The explicit inclusion of gluons implies
an unrealistically low separation scale.

</DOC>
<DOC>
<DOCNO> 11085 </DOCNO>
Exact and Truncated Dynamics in Nonequilibrium Field Theory


  Nonperturbative dynamics of quantum fields out of equilibrium is often
described by the time evolution of a hierarchy of correlation functions, using
approximation methods such as Hartree, large N, and nPI-effective action
techniques. These truncation schemes can be implemented equally well in a
classical statistical system, where results can be tested by comparison with
the complete nonlinear evolution obtained by numerical methods. For a 1+1
dimensional scalar field we find that the early-time behaviour is reproduced
qualitatively by the Hartree dynamics. The inclusion of direct scattering
improves this to the quantitative level. We show that the emergence of
nonthermal temperature profiles at intermediate times can be understood in
terms of the fixed points of the evolution equations in the Hartree
approximation. The form of the profile depends explicitly on the initial
ensemble. While the truncated evolution equations do not seem to be able to get
away from the fixed point, the full nonlinear evolution shows thermalization
with a (surprisingly) slow relaxation.

</DOC>
<DOC>
<DOCNO> 10731 </DOCNO>
Magnetic-field-induced Luttinger liquid


  It is shown that a strong magnetic field applied to a bulk metal induces a
Luttinger-liquid phase. This phase is characterized by the zero-bias anomaly in
tunneling: the tunneling conductance scales as a power-law of voltage or
temperature. The tunneling exponent increases with the magnetic field as BlnB.
The zero-bias anomaly is most pronounced for tunneling with the field applied
perpendicular to the plane of the tunneling junction.

</DOC>
<DOC>
<DOCNO> 118962 </DOCNO>
On The Cosmic Origins Of Carbon And Nitrogen


  We analyze the behavior of N/O and C/O abundance ratios as a function of
metallicity as gauged by O/H in large, extant Galactic and extragalactic H II
region abundance samples. Numerical chemical evolution models are computed
using published stellar yields implied by comparing analytical models to the
observations. Our results suggest that carbon and nitrogen originate from
separate production sites and are decoupled from one another. Massive stars
(M>8M_sun) dominate the production of carbon, while intermediate-mass stars
between 4 and 8 solar masses, with a characteristic ejection delay time of 250
Myr after their formation, dominate nitrogen production. Carbon production is
positively sensitive to metallicity through mass loss processes in massive
stars and has a pseudo-secondary character. Nitrogen production in intermediate
mass stars is primary at low metallicity, but clearly secondary (and perhaps
tertiary) when 12+log(O/H)>8.3. The observed flat behavior of N/O versus O/H in
metal-poor galaxies is explained by invoking low star formation rates which
flatten the age-metallicity relation and thereby allow N/O to rise to observed
levels at low metallicities. The observed scatter and distribution of data
points for N/O challenge the popular idea that intermittent polluting by oxygen
from massive stars is occurring following star bursts. The effect of inflow of
gas into galactic systems on secondary production of nitrogen from carbon may
introduce some scatter into N/O ratios at high metallicities.

</DOC>
<DOC>
<DOCNO> 101253 </DOCNO>
Koebe Domain of Starlike Functions of Complex Order with Montel


  Let $S^{*}(1-b)$ ($b \not= 0$ complex) denote the class of functions 
$f(z)=z+\alpha_{2}z^{2}+...$ analytic in $D={z \mid | z | < 1}$ which
satisfies,for $z=e^{i\theta} \in D$, $(f(z)/z)\not= 0$ in D, and $Re \Biggr
[ 1+ {1 \over b} \Biggr (z {{f^{'}(z)} \over f(z)}-1 \Biggl) \Biggl ] > 0$.
The aim of this paper is to give the Koebe domain of the above mentioned class.

</DOC>
<DOC>
<DOCNO> 120691 </DOCNO>
Genetic-Algorithm-based Asteroseismological Analysis of the DBV White


  White dwarf asteroseismology offers the opportunity to probe the structure
and composition of stellar objects governed by relatively simple physical
principles. The observational requirements of asteroseismology have been
addressed by the development of the Whole Earth Telescope (WET), but the
analytical procedures still need to be refined before this technique can yield
the complete physical insight that the data can provide. Toward this end, we
have utilized a genetic-algorithm-based optimization method to fit our models
to the observed pulsation frequencies of the DBV white dwarf GD 358 obtained
with the WET in 1990. This new approach has finally exploited the sensitivity
of our models to the core composition, and will soon yield some interesting
constraints on nuclear reaction cross-sections.

</DOC>
<DOC>
<DOCNO> 122791 </DOCNO>
Non-LTE analysis of neutral magnesium in cool stars


  Calculations of the statistical equilibrium of magnesium in the solar
photosphere have shown that NLTE populations hardly affect Mg line formation in
the Sun. However, in metal-poor dwarfs and giants the influence of electron
collisions is reduced, and the ultraviolet radiation field, enhanced due to
reduced background line opacity, results in more pronounced NLTE effects. In
thephotosphere of a cool star excitation and ionization due to collisions with
neutral hydrogen can outweigh electron collisions. Analyses based on NLTE
populations lead to significantly higher Mg abundances than those calculated
from LTE. We calculate magnesium abundances in 10 cool dwarfs and subgiants
with metallicities from -2.29 to 0.0. The results are based on spectra of
high-resolution and high signal-to-noise ratio. Stellar effective temperatures
are derived from Balmer line profiles,surface gravities from Hipparcos
parallaxes and the wings of the MgIb triplet, and metal abundances and
microturbulence velocities are obtained from LTE analyses of FeII line
profiles. For stars with metallicities between -2.0 < [Fe/H] < -1.0 abundance
corrections Delta{[Mg/H]_{NLTE-LTE}} ~ 0.05 - 0.11 are found. As expected the
corrections increase with decreasing metal abundance, and they increase
slightly with decreasing surface gravity. We also calculate the statistical
equilibrium of magnesium for series of model atmospheres with different stellar
parameters and find that $\Delta{\rm [Mg/H]_{NLTE-LTE}}$ increases with
effective temperature between 5200 and 6500 K. For extremely metal-poor stars
the abundance corrections approach Delta{[Mg/H]_{NLTE-LTE}} ~ 0.23 at [Fe/H] ~
-3.0.

</DOC>
<DOC>
<DOCNO> 120043 </DOCNO>
Dark energy and the Boomerang data


  The recent high-quality Boomerang data allow to test many competing
cosmological models. Here I present a seven-parameter likelihood analysis of
dark energy models with exponential potential and explicit coupling to dark
matter. Such a model is conformally equivalent to a scalar field with
non-minimal coupling to gravity. So far, the constraints on a dark energy -
dark matter coupling were extremely weak. The Boomerang data constrain the
dimensionless coupling $\beta $ to be smaller than 0.1, an order of magnitude
better than previous limits. In terms of the constant $\xi $ of non-minimally
coupled theories, this amounts to $\xi <0.01.$
  On the other hand, Boomerang has not enough sensitivity to put constraints on
the potential slope.

</DOC>
<DOC>
<DOCNO> 150939 </DOCNO>
Symmetric products, permutation orbifolds and discrete torsion


  Symmetric product orbifolds, i.e. permutation orbifolds of the full symmetric
group S_{n} are considered by applying the general techniques of permutation
orbifolds. Generating functions for various quantities, e.g. the torus
partition functions and the Klein-bottle amplitudes are presented, as well as a
simple expression for the discrete torsion coefficients.

</DOC>
<DOC>
<DOCNO> 101918 </DOCNO>
q-convolution and its q-Fourier transform


  The functions on a lattice generated by the integer degrees of $q^2$ are
considered, 0<q<1. The $q^2$-translation operator is defined. The
multiplicators and the $q^2$-convolutors are defined in the functional spaces
which are dual with respect to the $q^2$-Fourier transform. The $q^2$-analog of
convolution of two $q^2$-distributions is constructed. The $q^2$-analog of an
arbitrary (non integer) order derivative is introduced

</DOC>
<DOC>
<DOCNO> 118476 </DOCNO>
Initial operation of the International Gravitational Event Collaboration


  The International Gravitational Event Collaboration, IGEC, is a coordinated
effort by research groups operating gravitational wave detectors working
towards the detection of millisecond bursts of gravitational waves. Here we
report on the current IGEC resonant bar observatory, its data analysis
procedures, the main properties of the first exchanged data set. Even though
the available data set is not complete, in the years 1997 and 1998 up to four
detectors were operating simultaneously. Preliminary results are mentioned.

</DOC>
<DOC>
<DOCNO> 13094 </DOCNO>
Enumeration of simple random walks and tridiagonal matrices


  We present some old and new results in the enumeration of random walks in one
dimension, mostly developed in works of enumerative combinatorics. The relation
between the trace of the $n$-th power of a tridiagonal matrix and the
enumeration of weighted paths of $n$ steps allows an easier combinatorial
enumeration of the paths. It also seems promising for the theory of tridiagonal
random matrices .

</DOC>
<DOC>
<DOCNO> 10520 </DOCNO>
Theory of Transition Temperature of Magnetic Double Perovskites


  We formulate a theory of double perovskite coumpounds such as Sr$_2$FeReO$_6$
and Sr$_2$FeMoO$_6$ which have attracted recent attention for their possible
uses as spin valves and sources of spin polarized electrons. We solve the
theory in the dynamical mean field approximation to find the magnetic
transition temperature $T_c$. We find that $T_c$ is determined by a subtle
interplay between carrier density and the Fe-Mo/Re site energy difference, and
that the non-Fe same-sublattice hopping acts to reduce $T_c$. Our results
suggest that presently existing materials do not optimize $T_c$.

</DOC>
<DOC>
<DOCNO> 101363 </DOCNO>
From rotating needles to stability of waves; emerging connections


  We survey the interconnections between geometric combinatorics (such as the
Kakeya problem), arithmetic combinatorics (such as the classical problem of
determining which sets contain arithmetic progressions), oscillatory integrals
(such as the Bochner-Riesz, restriction, and local smoothing problems), and the
local and global well-posedness theory for non-linear dispersive and wave
equations.

</DOC>
<DOC>
<DOCNO> 121638 </DOCNO>
Deuterium-burning in substellar objects


  We consider the depletion of primordial deuterium in the interior of
substellar objects as a function of mass, age and absolute magnitude in several
photometric passbands. We characterize potential spectroscopic signatures of
deuterium in the lines of deuterated water HDO. These results will serve as a
useful, independent diagnostic to characterize the mass and/or the age of young
substellar objects, and to provide an independent age determination of very
young clusters. These results can serve to identify objects at the
deuterium-burning limit and to confront the theoretical prediction that
D-burning is a necessary condition to form star-like objects.

</DOC>
<DOC>
<DOCNO> 9359 </DOCNO>
Doped Stripes in Models for the Cuprates Emerging from the One-hole


  The extended and standard t-J models are computationally studied on ladders
and planes, with emphasis on the small J/t region. At couplings compatible with
photoemission results for undoped cuprates, half-doped stripes separating
$\pi$-shifted antiferromagnetic (AF) domains are found, as in Tranquada's
interpretation of neutron experiments. Our main result is that the elementary
stripe ``building-block'' resembles the properties of $one$ hole at small J/t,
with robust AF correlations across-the-hole induced by the local tendency of
the charge to separate from the spin (G. Martins {\it et al.}, Phys. Rev. B{\bf
60}, R3716 (1999)). This suggests that the seed of half-doped stripes already
exists in the unusual properties of the insulating parent compound.

</DOC>
<DOC>
<DOCNO> 9045 </DOCNO>
Bifurcations and a chaos strip in states of long Josephson junctions


  Stationary and nonstationary, in particular, chaotic states in long Josephson
junctions are investigated. Bifurcation lines on the parametric bias
current-external magnetic field plane are calculated. The chaos strip along the
bifurcation line is observed. It is shown that transitions between stationary
states are the transitions from metastable to stable states and that the
thermodynamical Gibbs potential of these stable states may be larger than for
some metastable states. The definition of a dynamical critical magnetic field
characterizing the stability of the stationary

</DOC>
<DOC>
<DOCNO> 68598 </DOCNO>
Borel-Pade vs Borel-Weniger method: a QED and a QCD example


  Recently, Weniger (delta sequence) method has been proposed by the authors of
Ref. [1] (Jentschura et al.) for resummation of truncated perturbation series
in quantum field theories. Those authors presented numerical evidence
suggesting that this method works better than Pade approximants when we resum a
function with singularities in the Borel plane but not on the positive axis. We
present here numerical evidence suggesting that in such cases the combined
method of Borel-Pade works better than its analog Borel-Weniger, and that it
may work better or comparably well in some of the cases when there are
singularities on the positive axis in the Borel plane.

</DOC>
<DOC>
<DOCNO> 101115 </DOCNO>
On crossed product of algebras


  The concept of a crossed tensor product of algebras is studied from a few
points of views. Some related constructions are considered. Crossed enveloping
algebras and their representations are discussed. Applications to the
noncommutative geometry and particle systems with generalized statistics are
indicated.

</DOC>
<DOC>
<DOCNO> 40359 </DOCNO>
A Measurement of the Branching Ratio of $K_L \to e^+e^-\gamma\gamma$


  We report on a study of the decay $K_L \to e^+e^-\gamma\gamma$ carried out as
a part of the KTeV/E799 experiment at Fermilab. The 1997 data yielded a sample
of 1543 events, including an expected background of $56 \pm 8$ events. An
effective form factor was determined from the observed distribution of the
$e^+e^-$ invariant mass. Using this form factor in the calculation of the
detector acceptance, the branching ratio was measured to be ${\mathcal B}(K_L
\to e^+ e^- \gamma \gamma, E^*_\gamma > 5 {MeV}) = (5.84 \pm 0.15 {\rm ~(stat)}
\pm 0.32 {\rm ~(sys)})\times 10^{-7}$.

</DOC>
<DOC>
<DOCNO> 118647 </DOCNO>
A Remarkable Angular Distribution of the Intermediate Subclass of


  In the article a test is developed, which allows to test the null-hypothesis
of the intrinsic randomness in the angular distribution of gamma-ray bursts
collected at the Current BATSE Catalog. The method is a modified version of the
well-known counts-in-cells test, and fully eliminates the non-uniform
sky-exposure function of BATSE instrument. Applying this method to the case of
all gamma-ray bursts no intrinsic non-randomness is found. The test also did
not find intrinsic non-randomnesses for the short and long gamma-ray bursts,
respectively. On the other hand, using the method to the new intermediate
subclass of gamma-ray bursts, the null-hypothesis of the intrinsic randomness
for 181 intermediate gamma-ray bursts is rejected on the 96.4% confidence
level. Taking 92 dimmer bursts from this subclass itself, we obtain the
surprising result: This "dim" subclass of the intermediate subclass has an
intrinsic non-randomness on the 99.3% confidence level. On the other hand, the
89 "bright" bursts show no intrinsic non-randomness.

</DOC>
<DOC>
<DOCNO> 169746 </DOCNO>
Atomic Quantum State Teleportation and Swapping


  A set of protocols for atomic quantum state teleportation and swapping
utilizing Einstein-Podolsky-Rosen light is proposed. The protocols are suitable
for collective spin states of a macroscopic sample of atoms, i.e. for
continuous atomic variables. Feasibility of experimental realization for
teleportation of a gas sample of atoms is analyzed.

</DOC>
<DOC>
<DOCNO> 9794 </DOCNO>
Remarks on Shannon's Statistical Inference and the Second Law in Quantum


  We comment on a formulation of quantum statistical mechanics, which
incorporates the statistical inference of Shannon.
  Our basic idea is to distinguish the dynamical entropy of von Neumann, $H =
-k Tr \hat{\rho}\ln\hat{\rho}$, in terms of the density matrix $\hat{\rho}(t)$,
and the statistical amount of uncertainty of Shannon, $S= -k \sum_{n}p_{n}\ln
p_{n}$, with $p_{n}=< n|\hat{\rho}|n>$ in the representation where the total
energy and particle numbers are diagonal. These quantities satisfy the
inequality $S\geq H$. We propose to interprete Shannon's statistical inference
as specifying the {\em initial conditions} of the system in terms of $p_{n}$. A
definition of macroscopic observables which are characterized by intrinsic time
scales is given, and a quantum mechanical condition on the system, which
ensures equilibrium, is discussed on the basis of time averaging.
  An interesting analogy of the change of entroy with the running coupling in
renormalization group is noted. A salient feature of our approach is that the
distinction between statistical aspects and dynamical aspects of quantum
statistical mechanics is very transparent.

</DOC>
<DOC>
<DOCNO> 150843 </DOCNO>
On dimensional reductions of the M-9-brane


  We discuss the relations of the M-9-brane with other branes via dimensional
reductions, mainly focusing on their Wess-Zumino (WZ) actions. It is shown that
on three kinds of dimensional reductions, the WZ action of the M-9-brane
respectively gives those of the D-8-brane, the ``KK-8A brane'' (which we regard
as a kind of D-8-brane) and the ``NS-9A brane'', the last two actions of which
were obtained via dualities. Based on these results, we conclude that the
relation of p-branes for $p\ge 8$, proposed previously, is consistent from the
viewpoint of worldvolume actions.

</DOC>
<DOC>
<DOCNO> 170312 </DOCNO>
A semidefinite program for distillable entanglement


  We show that the maximum fidelity obtained by a p.p.t. distillation protocol
is given by the solution to a certain semidefinite program. This gives a number
of new lower and upper bounds on p.p.t. distillable entanglement (and thus new
upper bounds on 2-locally distillable entanglement). In the presence of
symmetry, the semidefinite program simplifies considerably, becoming a linear
program in the case of isotropic and Werner states. Using these techniques, we
determine the p.p.t. distillable entanglement of asymmetric Werner states and
``maximally correlated'' states. We conclude with a discussion of possible
applications of semidefinite programming to quantum codes and 1-local
distillation.

</DOC>
<DOC>
<DOCNO> 68750 </DOCNO>
Light-Cone Wavefunctions and the Intrinsic Structure of Hadrons


  The light-cone Fock-state representation of QCD encodes the properties of a
hadrons in terms of frame-independent wavefunctions. A new type of jet
production reaction, "self-resolving diffractive interactions" can provide
direct information on the light-cone wavefunctions of hadrons in terms of their
quark and gluon degrees of freedom as well as the composition of nuclei in
terms of their nucleon and mesonic degrees of freedom. The relation of the
intrinsic sea to the light-cone wavefunctions is discussed. The decomposition
of light-cone spin is illustrated for the quantum fluctuations of an electron.

</DOC>
<DOC>
<DOCNO> 121507 </DOCNO>
SNR0540-69 -the Crab twin- revisited: Chandra vs. HST


  High resolution images of the Crab-like SNR SNR0540-69 have been recently
obtained by the HRC, on board the Chandra X-ray Observatory, and by the FORS1
instrument, attached to ESO/VLT1. A detailed comparison of these images with an
archival Planetary Camera one will be presented.

</DOC>
<DOC>
<DOCNO> 120828 </DOCNO>
The ING Instrumentation Conference Discussion, Options for a Competitive


  An expert panel initiated discussion on a number of key questions facing the
role of 4-m and small telescopes in the new era of 8-m telescopes. The panel
and audience agreed that the 4-m class telescope role would necessarily evolve,
but would still be important in the coming years. The need for an active
development programme of competitive instrumentation for 4-m class telescopes,
and in particular the William Herschel Telescope (WHT) was stressed. In
conjunction with this, the need to de-commission instrumentation made redundant
by 8-m class telescopes was noted. New operational modes, including greater
emphasis on survey programmes, and possibly queue scheduling, coupled with
changes to the procedures for allocating time were seen as desirable. The panel
and audience supported the Isaac Newton Group's emphasis on the development of
instrumentation to exploit its imminent deployment of the WHT's facility
Adaptive Optics system.

</DOC>
<DOC>
<DOCNO> 10705 </DOCNO>
Condensate Oscillations, Kinetic Equations and Two-Fluid Hydrodynamics


  This is based on 4 lectures given at the 13th Australian Physics Summer
School, Australia National University, Canberra, Jan 17-28, 2000. The main
topic is the theory of collective modes in a trapped Bose gas at finite
temperatures. A generalized Gross-Pitaevskii equation is derived at finite
temperatures, which is used to discuss a new mechanism for damping in the
collisionless region arising from interactions with a static thermal cloud of
non-condensate atoms. Next, introducing a kinetic equation for the thermal
cloud, we derive two-fluid equations of motion for the condensate and
non-condensate components in the collision-dominated hydrodynamic region. We
show that these are precisely the equivalent of the Landau two-fluid equations
in the limit that the two components are in diffusive local equilibrium.
However, our equations also predict the existence of a new zero frequency
relaxational mode, in addition to the usual Landau hydrodynamic modes (such as
first and second sound). The special importance and simplicity of two-fluid
hydrodynamics is stressed.

</DOC>
<DOC>
<DOCNO> 123188 </DOCNO>
Young star clusters in the Large Magellanic Cloud: NGC 1805 and NGC 1818


  We present colour-magnitude diagrams for two rich (~10^4 Msun) Large
Magellanic Cloud star clusters with ages ~10^7 years, constructed from optical
and near-infrared data obtained with the Hubble Space Telescope. These data are
part of an HST project to study LMC clusters with a range of ages. In this
paper we investigate the massive star content of the young clusters, and
determine the cluster ages and metallicities, paying particular attention to Be
star and blue straggler populations and evidence of age spreads. We compare our
data to detailed stellar population simulations to investigate the turn-off
structure of ~25 Myr stellar systems, highlighting the complexity of the blue
straggler phenomenon.

</DOC>
<DOC>
<DOCNO> 70951 </DOCNO>
Top Quarks at Photon Colliders


  A review of results on top quark physics expected at the Photon Linear
Colliders is presented.

</DOC>
<DOC>
<DOCNO> 68005 </DOCNO>
Metastable Gravitons and Infinite Volume Extra Dimensions


  We address the issue of whether extra dimensions could have an infinite
volume and yet reproduce the effects of observable four-dimensional gravity on
a brane. There is no normalizable zero-mode graviton in this case, nevertheless
correct Newton's law can be obtained by exchanging bulk gravitons. This can be
interpreted as an exchange of a single {\it metastable} 4D graviton. Such
theories have remarkable phenomenological signatures since the evolution of the
Universe becomes high-dimensional at very large scales. Furthermore, the bulk
supersymmetry in the infinite volume limit might be preserved while being
completely broken on a brane. This gives rise to a possibility of controlling
the value of the bulk cosmological constant. Unfortunately, these theories have
difficulties in reproducing certain predictions of Einstein's theory related to
relativistic sources. This is due to the van Dam-Veltman-Zakharov discontinuity
in the propagator of a massive graviton. This suggests that all theories in
which contributions to effective 4D gravity come predominantly from the bulk
graviton exchange should encounter serious phenomenological difficulties.

</DOC>
<DOC>
<DOCNO> 12386 </DOCNO>
Geometric invariant theory approach to the determination of ground


  A complete and rigorous determination of the possible ground states for
D-wave pairing Bose condensates is presented, using a geometrical invariant
theory approach to the problem. The order parameter is argued to be a vector,
transforming according to a ten dimensional real representation of the group
$G=${\bf O}$_3\otimes${\bf U}$_1\times <{\cal T}>$. We determine the equalities
and inequalities defining the orbit space of this linear group and its symmetry
strata, which are in a one-to-one correspondence with the possible distinct
phases of the system. We find 15 allowed phases (besides the unbroken one),
with different symmetries, that we thoroughly determine. The group-subgroup
relations between bordering phases are pointed out. The perturbative sixth
degree corrections to the minimum of a fourth degree polynomial $G$-invariant
free energy, calculated by Mermin, are also determined.

</DOC>
<DOC>
<DOCNO> 100441 </DOCNO>
A Dehn surgery description of regular finite cyclic covering spaces of


  We provide related Dehn surgery descriptions for rational homology spheres
and a class of their regular finite cyclic covering spaces. As an application,
we use the surgery descriptions to relate the Casson invariants of the covering
spaces to that of the base space. Finally, we show that this places
restrictions on the number of finite and cyclic Dehn fillings of the knot
complements in the covering spaces beyone those imposed by
Culler-Gordon-Luecke-Shalen and Boyer-Zhang.

</DOC>
<DOC>
<DOCNO> 116577 </DOCNO>
Analytical treatment of the emittance growth in the main Linacs of


  In this paper the single and multibunch emittance growths in the main linac
of a linear collider are analytically treated in analogy to the Brownian motion
of a molecule, and the analytical formulae for the emittance growth due to
accelerating structure misalignment errors are obtained by solving Langevin
equation. The same set of formulae is derived also by solving directly
Fokker-Planck equation. Comparisons with numerical simulation results are made
and the agreement is quite well.

</DOC>
<DOC>
<DOCNO> 68191 </DOCNO>
D0-Branes As Light-Front Confined Quarks


  We argue that different aspects of Light-Front QCD at confined phase can be
recovered by the Matrix Quantum Mechanics of D0-branes. The concerning Matrix
Quantum Mechanics is obtained from dimensional reduction of pure Yang-Mills
theory to 0+1 dimension. The aspects of QCD dynamics which are studied in
correspondence with D0-branes are: 1) phenomenological inter-quark potentials,
2) whiteness of hadrons and 3) scattering amplitudes. In addition, some other
issues such as the large-N behavior, the gravity--gauge theory relation and
also a possible justification for involving ``non-commutative coordinates'' in
a study of QCD bound-states are discussed.

</DOC>
<DOC>
<DOCNO> 116387 </DOCNO>
Can spontaneous symmetry breaking occur in potential with one minima?


  Spontaneous symmetry breaking occurs when the symmetry that a physical system
possesses, is not preserved for the ground state of the system. Although the
procedure of symmetry breaking is quite clear from the mathematical point of
view, the physical interpretation of the phenomenon is worth to be better
understood. In this note we present a simple and instructive example of the
symmetry breaking in a mechanical system. It demonstrates that the spontaneous
symmetry breaking can occur for the spatially extended solutions in a potential
characterised by a single minimum.

</DOC>
<DOC>
<DOCNO> 12349 </DOCNO>
Origin of scaling structure and non-gaussian velocity distribution in


  Fractal structures and non-Gaussian velocity distributions are characteristic
properties commonly observed in virialized self-gravitating systems such as
galaxies or interstellar molecular clouds. We study the origin of these
properties using the one-dimensional ring model which we newly propose in this
paper. In this simple model, $N$ particles are moving, on a circular ring fixed
in the three dimensional space, with mutual interaction of gravity. This model
is suitable for accurate symplectic integration method by which we find the
phase transition in this system from extended-phase to collapsed-phase through
an interesting phase (\halo-phase) which has negative specific heat. In this
intermediate energy scale, there appear scaling properties, non-thermal and
non-Gaussian velocity distributions. In contrast, these peculiar properties are
never observed in other \gas and \core phases. Particles in each phase have
typical time scales of motion determined by the cutoff length $\xi$, the ring
radius $R$ and the total energy $E$. Thus all relaxation patterns of the system
are determined by these three time scales.

</DOC>
<DOC>
<DOCNO> 174470 </DOCNO>
Directed flow of antiprotons in Au+Au collisions at AGS


  Directed flow of antiprotons is studied in Au+Au collisions at a beam
momentum of 11.5A GeV/c. It is shown that antiproton directed flow is
anti-correlated to proton flow. The measured transverse momentum dependence of
the antiproton flow is compared with predictions of the RQMD event generator.

</DOC>
<DOC>
<DOCNO> 70478 </DOCNO>
Rotating relativistic superfluid


  Relativistic equation of state and velocity comparable with the speed of
light are included in consideration of a superfluid rotating in a cylindrical
container. Minimizing the free energy, we derive the equation of motion. It
admits an analytic solution, the solid-body rotation inside and irrotational
motion near the walls of the vessel, providing the vortex quantum is not
extremely high with respect to the particle rest mass that is satisfied for
real astrophysical objects. The relativistic velocity of the vessel and the
relativistic equation of state results to the deviation of the angular velocity
of the solid-body motion inside and that of the vessel. The boundary between
the solid-body and irrotational motion is also shifted sufficiently leading to
a difference between the total angular momentum of superfluid and the normal
matter.

</DOC>
<DOC>
<DOCNO> 68490 </DOCNO>
Bulk Fields and Supersymmetry in a Slice of AdS


  Five-dimensional models where the bulk is a slice of AdS have the virtue of
solving the hierarchy problem. The electroweak scale is generated by a ``warp''
factor of the induced metric on the brane where the standard model fields live.
However, it is not necessary to confine the standard model fields on the brane
and we analyze the possibility of having the fields actually living in the
slice of AdS. Specifically, we study the behaviour of fermions, gauge bosons
and scalars in this geometry and their implications on electroweak physics.
These scenarios can provide an explanation of the fermion mass hierarchy by
warp factors. We also consider the case of supersymmetry in the bulk, and
analyze the conditions on the mass spectrum. Finally, a model is proposed where
the warp factor generates a small (TeV) supersymmetry-breaking scale, with the
gauge interactions mediating the breaking to the scalar sector.

</DOC>
<DOC>
<DOCNO> 99870 </DOCNO>
Tamarkin's proof of Kontsevich formality theorem


  In 1998 D. Tamarkin announced a proof of Kontsevich formality theorem based
on the existence of structure of homotopy Gerstenhaber algebra in the
Hochschild cochains of an associative algebra. In this note we give a detailed
explanation of Tamarkin's result.

</DOC>
<DOC>
<DOCNO> 101423 </DOCNO>
Annihilation Theorem and Separation Theorem for basic classical Lie


  In this article we prove that for a basic classical Lie superalgebra the
annihilator of a strongly typical Verma module is a centrally generated ideal.
For a basic classical Lie superalgebra of type I we prove that the localization
of the enveloping algebra by a certain central element is free over its centre.

</DOC>
<DOC>
<DOCNO> 12074 </DOCNO>
Fractional quantum Hall junctions and two-channel Kondo models


  A mapping between fractional quantum Hall (FQH) junctions and the two-channel
Kondo model is presented. We discuss in detail this relation for the particular
case of a junction of a FQH state at $\nu = 1/3$ and a normal metal. We show
that in the strong coupling regime this junction has a non-Fermi liquid fixed
point. At this fixed point the electron Green's function has a branch cut, and
the entropy has a non-zero value equal to $S={1/2} \ln{2}$. We construct the
space of perturbations at the strong coupling fixed point and find that the
dimensions of the tunneling operator is 1/2. These behaviors are strongly
reminiscent of the non-Fermi liquid fixed point of a number of quantum impurity
models, particularly the two-channel Kondo model. However we have found that,
in spite of these similarities, the Hilbert spaces of these two systems are
quite different. In particular, although in a special limit the Hamiltonians of
both models are the same, their Hilbert spaces are not since they are
determined by physically distinct boundary conditions. As a consequence the
spectrum of operators in both models is different.

</DOC>
<DOC>
<DOCNO> 10468 </DOCNO>
Cooperative Electromagnetic Effects


  Collective phenomena in strongly nonequilibrium systems interacting with
electromagnetic field are considered. Such systems are described by complicated
nonlinear differential or integro-differential equations. The aim of this
review is to show that many nonlinear collective phenomena can be successfully
treated by a recently developed method called the Scale Separation Approach
whose name is due to the idea of separating different characteristic space-time
scales existing in nonequilibrium statistical systems. This approach is rather
general and can be applied to various nonequilibrium physical problems, several
of which are discussed here. The problems considered not only serve as
illustrations of the method but are quite important by themselves presenting
interesting physical effects, such as Collective Liberation of Light, Turbulent
Photon Filamentation, Superradiant Spin Relaxation, Negative Electric Current,
and Magnetic Semiconfinement of Atoms.

</DOC>
<DOC>
<DOCNO> 84242 </DOCNO>
General Relativistic Stars: Linear Equations of State


  In this paper Einstein's field equations, for static spherically symmetric
perfect fluid models with a linear barotropic equation of state, are recast
into a 3-dimensional regular system of ordinary differential equations on a
compact state space. The system is analyzed qualitatively, using the theory of
dynamical systems, and numerically. It is shown that certain special solutions
play important roles as building blocks for the solution structure in general.
In particular, these special solutions determine many of the features exhibited
by solutions with a regular center and large central pressure. It is also shown
that the present approach can be applied to more general classes of barotropic
equations of state.

</DOC>
<DOC>
<DOCNO> 120535 </DOCNO>
Spectral Variability of QSOs in the Optical Band


  A new analysis of the variability of the spectral slope of PG QSOs has been
performed, on the basis of recent literature data in the B and R photometric
bands. Preliminary results confirm our previous findings concerning the
increase of variability with the rest-frame observing frequency. We also find a
correlation of the spectral slope with luminosity, consistent with temperature
changes of an emitting black body.

</DOC>
<DOC>
<DOCNO> 117601 </DOCNO>
Dark Matter Halos Simulated with Million Particles


  We report a series of high-resolution N-body simulations designed to examine
the internal physical properties of dark matter halos. A total of fifteen
halos, each represented by $\sim 1$ million particles within the virial radius,
have been simulated covering the mass range of $2\times10^{12}\sim
5\times10^{14} h^{-1}{\rm M_\odot}$. As the first application of these
simulations, we have examined the density profiles of the halos. We found a
clear systematic correlation between the halo mass and the slope of the density
profile at one percent of the virial radius, in addition to the variations of
the slope among halos of the similar mass. More specifically, the slope is
$\sim - 1.5$, -1.3, and -1.1 for galaxy, group, and cluster mass halos,
respectively. Thus we conclude that the dark matter density profiles,
especially in the inner region, are not universal.

</DOC>
<DOC>
<DOCNO> 101168 </DOCNO>
Quantum Mechanical Symmetries and Topological Invariants


  We give the definition and explore the algebraic structure of a class of
quantum symmetries, called topological symmetries, which are generalizations of
supersymmetry in the sense that they involve topological invariants similar to
the Witten index. A topological symmetry (TS) is specified by an integer n>1,
which determines its grading properties, and an n-tuple of positive integers
(m_1,m_2,...,m_n). We identify the algebras of supersymmetry, p=2
parasupersymmetry, and fractional supersymmetry of order n with those of the
Z_2-graded TS of type (1,1), Z_2-graded TS of type (2,1), and Z_n-graded TS of
type (1,1,...,1), respectively. We also comment on the mathematical
interpretation of the topological invariants associated with the Z_n-graded TS
of type (1,1,...,1). For n=2, the invariant is the Witten index which can be
identified with the analytic index of a Fredholm operator. For n>2, there are n
independent integer-valued invariants. These can be related to differences of
the dimension of the kernels of various products of n operators satisfying
certain conditions.

</DOC>
<DOC>
<DOCNO> 9263 </DOCNO>
Fluctuation interaction of particles in a fluid


  The interaction of bodies in a fluid, mediated by hydrodynamic fluctuations
and proposed by Dzyaloshinskii, Lifshitz, and Pitaevskii, is calculated exactly
for parallel infinite planes and is shown to be attractive. The second
mechanism of fluctuation interaction, proposed in the present work, is due to
fluctuations of linear and angular velocities of bodies in a hydrodynamic
medium and leads to a repulsion. The both mechanisms provide an interaction
energy of two particles in a fluid of the order of temperature for the
inter-particle distance of the micron scale, where the interaction mediated by
electromagnetic fluctuations is small. When two particles approaches a wall,
placed inside a fluid, the first (attractive) interaction is violated a little,
but the second (repulsive) weakens. This behavior correlates with the
experimentally observed attraction of particles which appears when they
approach a wall.

</DOC>
<DOC>
<DOCNO> 83475 </DOCNO>
Web Mining Research: A Survey


  With the huge amount of information available online, the World Wide Web is a
fertile area for data mining research. The Web mining research is at the cross
road of research from several research communities, such as database,
information retrieval, and within AI, especially the sub-areas of machine
learning and natural language processing. However, there is a lot of confusions
when comparing research efforts from different point of views. In this paper,
we survey the research in the area of Web mining, point out some confusions
regarded the usage of the term Web mining and suggest three Web mining
categories. Then we situate some of the research with respect to these three
categories. We also explore the connection between the Web mining categories
and the related agent paradigm. For the survey, we focus on representation
issues, on the process, on the learning algorithm, and on the application of
the recent works as the criteria. We conclude the paper with some research
issues.

</DOC>
<DOC>
<DOCNO> 12575 </DOCNO>
Local magnetic properties of periodic nonuniform spin-1/2 XX chains


  Using the Jordan-Wigner fermionization, Green function approach and continued
fractions we examine rigorously the local magnetizations and the local static
susceptibilities of the spin-1/2 XX chain in a transverse field with regularly
varying exchange interactions. We discuss our findings from a viewpoint of the
strong-coupling approach.

</DOC>
<DOC>
<DOCNO> 119943 </DOCNO>
Rapid Synchrotron Flares from BL Lacertae Detected by ASCA and RXTE


  We report the variable X-ray emission from BL Lacertae detected in the ASCA
ToO observation conducted during the EGRET and RXTE pointings, coincident with
the 1997 July outburst. The source showed a historically high state of X-ray,
optical, and gamma-ray emission, with its 2-10 keV flux peaking at ~3.3 E-11
erg/cm2/s. This is more than 3 times higher than the value measured by ASCA in
1995. We detected two rapid flares which occured only in the soft X-ray band,
while the hard X-ray flux also increased, but decayed with a much longer time
scale. Together with the requirement of a very steep and varying power law
dominating the soft X-ray band in addition to the hard power law, we suggest
that both the high energy end of the synchrotron spectrum and the hard inverse
Compton spectrum were visible in this source during the outburst. We discuss
the possible origins of the observed variability time scales, and interpret the
short time scales of the soft X-ray variability as reflecting the size of the
emission region.

</DOC>
<DOC>
<DOCNO> 84893 </DOCNO>
Quantization of the Taub cosmological model with extrinsic time


  The paper addresses the quantization of minisuperspace cosmological models,
with application to the Taub Model. By desparametrizing the model with an
extrinsic time, a formalism is developed in order to define a conserved
Schr\"{o}dinger inner product in the space of solutions of the Wheeler-De Witt
equation. A quantum version of classical canonical transformations is
introduced for connecting the solutions of the Wheeler-De Witt equation with
the wave functions of the desparametrized system. Once this correspondence is
established, boundary conditions on the space of solutions of the Wheeler-De
Witt equation are found to select the physical subspace. The question of
defining boundary conditions on the space of solutions of the Wheeler-De Witt
equation without having reduced the system is examined.

</DOC>
<DOC>
<DOCNO> 11691 </DOCNO>
Standard-model bundles


  We describe a family of genus one fibered Calabi-Yau threefolds with
fundamental group ${\mathbb Z}/2$. On each Calabi-Yau $Z$ in the family we
exhibit a positive dimensional family of Mumford stable bundles whose symmetry
group is the Standard Model group $SU(3)\times SU(2)\times U(1)$ and which have
$c_{3} = 6$. We also show that for each bundle $V$ in our family, $c_{2}(Z) -
c_{2}(V)$ is the class of an effective curve on $Z$. These conditions ensure
that $Z$ and $V$ can be used for a phenomenologically relevant compactification
of Heterotic M-theory.

</DOC>
<DOC>
<DOCNO> 100178 </DOCNO>
Non-archimedean intersection indices on projective spaces and the


  Inspired by Manin's approach towards a geometric interpretation of Arakelov
theory at infinity, we interpret in this paper non-Archimedean local
intersection numbers of linear cycles in $P^{n-1}$ with the combinatorial
geometry of the Bruhat-Tits building associated to PGL(n).

</DOC>
<DOC>
<DOCNO> 83468 </DOCNO>
Extended Abstract - Model-Based Debugging of Java Programs


  Model-based reasoning is a central concept in current research into
intelligent diagnostic systems. It is based on the assumption that sources of
incorrect behavior in technical devices can be located and identified via the
existence of a model describing the basic properties of components of a certain
application domain. When actual data concerning the misbehavior of a system
composed from such components is available, a domain-independent diagnosis
engine can be used to infer which parts of the system contribute to the
observed behavior. This paper describes the application of the model-based
approach to the debugging of Java programs written in a subset of Java. We show
how a simple dependency model can be derived from a program, demonstrate the
use of the model for debugging and reducing the required user interactions,
give a comparison of the functional dependency model with program slicing, and
finally discuss some current research issues.

</DOC>
<DOC>
<DOCNO> 122413 </DOCNO>
Star Formation History and Stellar Metallicity Distribution in a Cold


  We study star formation history and stellar metallicity distribution in
galaxies in a Lambda cold dark matter universe using a hydrodynamic
cosmological simulation. Our model predicts star formation rate declining in
time exponentially from an early epoch to the present with the time-scale of 6
Gyr, which is consistent with the empirical Madau plot with modest dust
obscuration. Star formation in L^* galaxies continues intermittently to the
present also with an exponentially declining rate of a similar time-scale,
whereas in small galaxies star formation ceases at an early epoch. The mean age
of the extant stars decreases only slowly with increasing redshift, and exceeds
1 Gyr at z=3. Normal galaxies contain stars with a wide range of metallicity
and age: stars formed at z<1 have metallicity of 0.1-1.0 Zsun, while old stars
take a wide range of values from 10^{-6} Zsun to 3.0 Zsun. The mean metallicity
of normal galaxies is in the range 0.1-1.0 Zsun. Dwarf galaxies that contain
only old stars have a wide range of mean metallicity (10^{-4}-1.0 Zsun), but on
average they are metal deficient compared with normal galaxies.

</DOC>
<DOC>
<DOCNO> 120326 </DOCNO>
Neutron Stars and Quantum Billiards


  Homogeneous neutron matter at subnuclear densities becomes unstable towards
the formation of inhomogeneities. Depending on the average value of the neutron
density one can observe the appearance of either bubbles, rods, tubes or plates
embeded in a neutron gas. We estimate the quantum corrections to the ground
state energy (which could be termed either shell correction or Casimir energy)
of such phases of neutron matter. The calculations are performed by evaluating
the contribution of the shortest periodic orbits in the Gutzwiller trace
formula for the density of states. The magnitude of the quantum corrections to
the ground state energy of neutron matter are of the same order as the energy
differences between various phases.

</DOC>
<DOC>
<DOCNO> 101332 </DOCNO>
Rational polynomials of simple type


  We classify two-variable polynomials which are rational of simple type. These
are precisely the two-variable polynomials with trivial homological monodromy.

</DOC>
<DOC>
<DOCNO> 9361 </DOCNO>
Dirac Fermions on a Two-Dimensional Lattice and the Intermediate


  Consequences of different discretizations of the two-dimensional Dirac
operator on low energy properties (e.g., the number of nodes) and their
relations to gauge properties are discussed. Breaking of the gauge invariance
was suggested in a recent work by M. Bocquet, D. Serban, and M.R. Zirnbauer
[cond-mat/9910480] in order to destroy an intermediate metallic phase of
lattice Dirac fermions with random mass. It is explained that such a procedure
is inconsistent with the underlying lattice physics. Previous results point out
that the logarithmic growth of the slope of the average density of states with
the system size, obtained in the field-theoretical calculation of M. Bocquet et
al., could be a precursor for the appearence of an intermediate metallic phase.

</DOC>
<DOC>
<DOCNO> 67717 </DOCNO>
Ordinary and radiative muon capture on the proton and the pseudoscalar


  We calculate ordinary and radiative muon capture on the proton in an
effective field theory of pions, nucleons and delta isobars, working to third
and second order in the small scale expansion respectively. Preceding
calculations in chiral effective field theories only employed pion and nucleon
degrees of freedom and were not able to reproduce the photon spectrum in the
pioneering experiment of radiative muon capture on the proton from TRIUMF. For
the past few years it has been speculated that the discrepancy between theory
and experiment might be due to Delta(1232) related effects, which are only
included via higher order contact interactions in the standard chiral approach.
In this report we demonstrate that this speculation does not hold true. We show
that contrary to expectations from naive dimensional analysis isobar effects on
the photon spectrum and the total rate in radiative muon capture are of the
order of a few percent, consistent with earlier findings in a more
phenomenological approach. We further demonstrate that both ordinary and
radiative muon capture constitute systems with a very well behaved chiral
expansion, both in standard chiral perturbation theory and in the small scale
expansion, and present some new ideas that might be at the bottom of the still
unresolved discrepancy between theory and experiment in radiative muon capture.
Finally we comment upon the procedure employed by the TRIUMF group to extract
new information from their radiative muon capture experiment on the
pseudoscalar form factor of the nucleon. We show that it is inconsistent with
the ordinary muon capture data.

</DOC>
<DOC>
<DOCNO> 13465 </DOCNO>
Functional Renormalization Prediction of Rupture


  We develop theoretical formulas for the prediction of the rupture of systems
which are known to exhibit a critical behavior, based solely on the knowledge
of the early time evolution of an observable, such as the acoustic emission
rate as a function of time or of stress.
 From the parameterization of such early time evolution in terms of a low-order
polynomial, we use the functional renormalization approach introduced by
Yukalov and Gluzman to transform this polynomial into a function which is
asymptotically a power law. The value of the critical time tc,conditioned on
the assumption that tc exists, is thus determined from the knowledge of the
coefficients of the polynomials. We test with success this prediction scheme
with respect to the order of the polynomials and as a function of noise.

</DOC>
<DOC>
<DOCNO> 100472 </DOCNO>
Families of maximal subbundles of stable vector bundles on curves


  Let X be a smooth projective curve of genus g bigger then 2. For any vector
bundle E on X let M_k(E) be the scheme of all rank k subbundles of E with
maximal degree. For every integers r, k and x with 0<k<r, x positive and either
x less then (k-1)(r-2k+1) (if 2k is less then r) or (r-k-1)(2k-r+1) (if 2k> r),
we construct a rank r stable vector bundle E such that M_k(E) has an
irreducible component of dimension x. Furthermore, if there exists a stable
vector bundle F with small Lange's invariant s_k(F) and with M_k(F) `spread
enough', then X i s a multiple covering of a curve of genus bigger then 2.

</DOC>
<DOC>
<DOCNO> 102851 </DOCNO>
A Note on a Specific Pencil of Conics in the Galois Fields of Order 2^n


  The pencil of conics featuring three degenerate conics each of which is a
line-pair is briefly inspected in a Galois field of characteristic two. It is
shown that if two degenerates are conjugate imaginary line pairs, the third
must be a real line pair; this contradicts Campbell's claim (Campbell 1927)
that all the three singular conics are conjugate imaginary line pairs.

</DOC>
<DOC>
<DOCNO> 118395 </DOCNO>
Magnetic field strength from peaked synchrotron spectra


  Key diagnostics of non-thermal plasmas, such as the position of the
synchrotron self-absorption turnover or the Faraday rotation optical depth,
depend crucially on the unobserved low-energy electron spectrum. We investigate
the effect of physically viable assumptions about the low-energy electron
spectrum on the magnetic field strength as inferred from the position of the
peak in the synchrotron spectrum marking the transition from optically thick to
optically thin radiation. To this end the kinetic equations are written down
and stationary solutions are given. In this context the inviability of the
delta function approximation of the synchrotron power spectrum is discussed.
Using two different approaches, we show that the field determination is
independent of the assumptions about the low energy electron spectrum within an
order of magnitude. As an example, we use our result to obtain a small
correction to the limiting brightness temperature.

</DOC>
<DOC>
<DOCNO> 83371 </DOCNO>
Succinct quantum proofs for properties of finite groups


  In this paper we consider a quantum computational variant of nondeterminism
based on the notion of a quantum proof, which is a quantum state that plays a
role similar to a certificate in an NP-type proof. Specifically, we consider
quantum proofs for properties of black-box groups, which are finite groups
whose elements are encoded as strings of a given length and whose group
operations are performed by a group oracle. We prove that for an arbitrary
group oracle there exist succinct (polynomial-length) quantum proofs for the
Group Non-Membership problem that can be checked with small error in polynomial
time on a quantum computer. Classically this is impossible--it is proved that
there exists a group oracle relative to which this problem does not have
succinct proofs that can be checked classically with bounded error in
polynomial time (i.e., the problem is not in MA relative to the group oracle
constructed). By considering a certain subproblem of the Group Non-Membership
problem we obtain a simple proof that there exists an oracle relative to which
BQP is not contained in MA. Finally, we show that quantum proofs for
non-membership and classical proofs for various other group properties can be
combined to yield succinct quantum proofs for other group properties not having
succinct proofs in the classical setting, such as verifying that a number
divides the order of a group and verifying that a group is not a simple group.

</DOC>
<DOC>
<DOCNO> 117334 </DOCNO>
Intrabeam Scattering Analysis of ATF Beam Data Taken in April 2000


  In April 2000 the single bunch energy spread, bunch length, horizontal
emittance, and vertical emittance were measured as functions of current in
KEK's ATF damping ring. In this report the measurement results are analyzed in
light of intrabeam scattering theory. The measurements are found to be
relatively consistent with theory, although the measured effects appear to be
stronger than theory. In addition, the factor of 3 growth in vertical emittance
at a current of 3 mA does not seem to be supported.

</DOC>
<DOC>
<DOCNO> 12889 </DOCNO>
A study of nanocrystalline cobalt prepared by ball milling


  The hcp-fcc transformation induced in cobalt powder by ball milling at room
temperature was studied using the excess Gibbs free energy for the metals, in
nanometric form, to calculate the activation energy that the atoms need for the
phase transformation to occur. The crystalline component of the nanocrystalline
cobalt produced in our laboratory, via ball milling, was analized using the
radial distribution function technique. The results suggest that the
crystalline component has the same structure as the bulk, contradicting results
already reported.

</DOC>
<DOC>
<DOCNO> 8154 </DOCNO>
Competing neural networks: Finding a strategy for the game of matching


  The ability of a deterministic, plastic system to learn to imitate stochastic
behavior is analyzed. Two neural networks -actually, two perceptrons- are put
to play a zero-sum game one against the other. The competition, by acting as a
kind of mutually supervised learning, drives the networks to produce an
approximation to the optimal strategy, that is to say, a random signal.

</DOC>
<DOC>
<DOCNO> 68316 </DOCNO>
Lepton flavor violation in the Randall-Sundrum model with bulk neutrinos


  Lepton flavor violation in the Randall-Sundrum model with bulk neutrinos is
considered. Grossman and Neubert recently proposed that the existence of tiny
neutrino masses and large mixing could be explained by the presence of the bulk
neutrinos in the Randall-Sundrum background. Since the zero mode wave functions
of the bulk neutrinos are localized on Planck brane, the Dirac Yukawa couplings
on our brane are exponentially suppressed enough to generate tiny neutrino
masses. However, the existence of Kaluza-Klein modes of these bulk neutrinos
enhance lepton flavor violating processes such as $\mu \to e \gamma$, from
which lower bounds on their masses can be derived. We find that the first KK
mode must be heavier than 25 TeV if all the neutrino Yukawa couplings are of
order unity, which requires a fine-tuning for the Higgs mass parameter.

</DOC>
<DOC>
<DOCNO> 13800 </DOCNO>
The excitations of the sympletic integrable models and their


  The Bethe ansatz equations of the fundamental Sp(2N) integrable model are
solved by a peculiar configuration of roots leading us to determine the nature
of the excitations. They consist of N elementary generalized spinons and N-1
composite excitations made by special convolutions between the spinons. This
fact is essential to determine the low-energy behaviour which is argued to be
described in terms of 2N Majorana fermions. Our results have practical
applications to spin-orbital systems and also shed new light to the connection
between integrable models and Wess-Zumino-Witten field theories.

</DOC>
<DOC>
<DOCNO> 174607 </DOCNO>
Fragmentation of relativistic oxygen nuclei in interactions with a


  The data on investigation of inelastic interactions of $16^O$ nuclei with a
proton at 3.25 A GeV/c momentum by the bubble chamber method are presented. The
separate characteristics as fragments isotopic composition and as topo-logical
cross sections of fragmentation channels are given. The processes of light
fragments formation and breakup of $16^O$ nucleus on multicharge fragments have
been investigated. The comparison of experimental data with the calculations by
statistical multifragmentation model was conducted.

</DOC>
<DOC>
<DOCNO> 151563 </DOCNO>
SL(2, Z) Duality and 4-Dimensional Noncommutative Theories


  We investigate how the four-dimensional noncommutative open string/Yang-Mills
theory behaves under a general non-perturbative quantum $SL(2,Z)$ symmetry
transformation. We discuss this by considering D3 branes in a constant
background of axion, dilaton, and electric and magnetic fields (including both
$ {\bf E} \perp {\bf B}$ and {\bf E}$||${\bf B} cases) in the respective
decoupling limit. We find that the value of axion, whether rational or
irrational, determines the nature of the resulting theory under $SL(2,Z)$ as
well as its properties such as the coupling constant and the number of
noncommutative directions. In particular, a strongly coupled theory with an
irrational value of axion can never be physically equivalent to a weakly
coupled theory while this is usually true for a theory with a rational value of
axion. A noncommutative Yang-Mills (NCYM) (resulting from D3 branes with pure
magnetic flux) is physically equivalent to a noncommutative open string (NCOS)
but if the value of axion is irrational, we also have noncommutative
space-space directions in addition to the usual noncommutative space-time
directions for NCOS. We also find in general that a NCOS cannot be physically
equivalent to a NCYM but to another NCOS if the value of axion is irrational.
We find another new decoupling limit for possible light-like NCYM whose
$SL(2,Z)$ duality is a light-like ordinary Yang-Mills if the value of the axion
is rational. Various related questions are also discussed.

</DOC>
<DOC>
<DOCNO> 9525 </DOCNO>
A Luttinger's theorem revisited


  For uniform systems of spin-less fermions in d spatial dimensions with d > 1,
interacting through the isotropic two-body potential v(r-r'), a celebrated
theorem due to Luttinger (1961) states that under the_assumption_ of validity
of the many-body perturbation theory the self-energy Sigma(k;epsilon), with 0
<,= k <,~ 3 k_F (where k_F stands for the Fermi wavenumber), satisfies the
following universal asymptotic relation as epsilon approaches the Fermi energy
epsilon_F: Im[Sigma(k;epsilon)] ~ -,+ alpha_k (epsilon-epsilon_F)^2, epsilon
>,< epsilon_F, with alpha_k >,= 0. As this is, by definition, specific to
self-energies of Landau Fermi-liquid systems, treatment of non-Fermi-liquid
systems are therefore thought to lie outside the domain of applicability of the
many-body perturbation theory; that, for these systems, the many-body
perturbation theory should_necessarily_ break down. We demonstrate that
Im[Sigma(k;epsilon)] ~ -,+ alpha_k (epsilon-epsilon_F)^2, epsilon >,<
epsilon_F, is_implicit_ in Luttinger's proof and that, for d > 1, in principle
nothing prohibits a non-Fermi-liquid-type (and, in particular
Luttinger-liquid-type) Sigma(k;epsilon) from being obtained within the
framework of the many-body perturbation theory. We in addition indicate how
seemingly innocuous Taylor expansions of the self-energy with respect to k,
epsilon or both amount to tacitly assuming that the metallic system under
consideration is a Fermi liquid, whether the self-energy is calculated
perturbatively or otherwise. Proofs that a certain metallic system is in a
Fermi-liquid state, based on such expansions, are therefore tautologies.

</DOC>
<DOC>
<DOCNO> 68592 </DOCNO>
Revisiting the U_A(1) problems


  We survey various U_A(1) problems and attempt to resolve the two puzzles
related to the eta mesons that have experimental verification. Specifically, we
first explore the Goldstone structure of the eta and eta' mesons in the context
of eta-eta' mixing using ideas based on QCD. Then we study the eta decays
eta->3pi0, eta'->3pi0 and eta'->eta pi pi. Finally we arrive at essentially the
same picture in the dynamical scheme based on consistently coupled
Schwinger-Dyson and Bethe-Salpeter integral equations. This chirally
well-behaved bound-state approach clarifies the distinction between the usual
axial-current decay constants and the gamma gamma decay constants in the
eta-eta' complex. Allowing for the effects of the SU(3) flavor symmetry
breaking in the quark-antiquark annihilation, leads to the improved eta-eta'
mass matrix.

</DOC>
<DOC>
<DOCNO> 152330 </DOCNO>
Non-Critical Poincar\'e Invariant Bosonic String Backgrounds and Closed


  A new family of non critical bosonic string backgrounds in arbitrary space
time dimension $D$ and with $ISO(1,D-2)$ Poincar\'e invariance are presented.
The metric warping factor and dilaton agree asymptotically with the linear
dilaton background. The closed string tachyon equation of motion enjoys, in the
linear approximation, an exact solution of ``kink'' type interpolating between
different expectation values. A renormalization group flow interpretation
,based on a closed string tachyon potential of type $-T^{2}e^{-T}$, is
suggested.

</DOC>
<DOC>
<DOCNO> 68143 </DOCNO>
Comment on ``Closing the neutrinoless double beta decay window into VEP


  The constraints from the non-observation of neutrinoless double beta decay on
the violations of Lorentz invariance (VLI) or violations of the equivalence
principle (VEP) have recently been re-examined (hep-ph/9904298) and it was
claimed that the constraints are not valid. In this reply we point out that
this statement is not correct and prove that the arguments given are wrong.

</DOC>
<DOC>
<DOCNO> 151945 </DOCNO>
Absence of Axial Anomaly in the Background of the Bohm-Aharonov Vector


  The problem of the axial anomaly in the presence of the Bohm-Aharonov gauge
vector field is exactly solved.

</DOC>
<DOC>
<DOCNO> 150356 </DOCNO>
Magnetic Catalysis of Chiral Symmetry Breaking in Gauge Theories


  Non-perturbative effect of the formation of a chiral symmetry breaking
condensate <\bar\psi\psi> and of a dynamically generated fermion mass in QED in
the presence of an external magnetic field is considered. The dynamical mass of
a fermion (energy gap in the fermion spectrum) is shown to depend essentially
nonanalytically on the renormalized coupling constant \alpha in a strong
magnetic field. Possible applications of this effect are discussed.

</DOC>
<DOC>
<DOCNO> 152423 </DOCNO>
On the construction of corrected Light-Front Hamiltonian for QED_2


  The counterterms, which must be included into Light-Front Hamiltonian of
$QED_2$ to get the equivalence with conventional Lorentz-covariant formulation,
are found. This is done to all orders of perturbation theory in fermion mass,
using the bosonization at intermediate steps and comparing Light-Front and
Lorentz-covariant perturbation theories for bosonized model. The obtained
Light-Front Hamiltonian contains all terms, present in the $QED_2$ theory,
canonically (naively) quantized on the Light-Front (in the Light-Front gauge)
and an unusual counterterm. This counterterm is proportional to linear
combination of fermion zero modes (which are multiplied by some operator
factors neutralizing their charge and fermionic number). The coefficients
before these zero mode operators are UV finite and depend on condensate
parameter in the $\theta$-vacuum. These coefficients are proportional to
fermion mass, when this mass goes to zero.

</DOC>
<DOC>
<DOCNO> 10584 </DOCNO>
Spin fluctuations in nearly magnetic metals from ab-initio dynamical


  We describe our theoretical formalism and computational scheme for making
ab-initio calculations of the dynamic paramagnetic spin susceptibilities of
metals and alloys at finite temperatures. Its basis is Time-Dependent Density
Functional Theory within an electronic multiple scattering, imaginary time
Green function formalism. Results receive a natural interpretation in terms of
overdamped oscillator systems making them suitable for incorporation into spin
fluctuation theories. For illustration we apply our method to the nearly
ferromagnetic metal Pd and the nearly antiferromagnetic chromium alloy Cr95V5.
We compare and contrast the spin dynamics of these two metals and in each case
identify those fluctuations with relaxation times much longer than typical
electronic `hopping times'

</DOC>
<DOC>
<DOCNO> 151308 </DOCNO>
The SQCD vacuum coupled to supergravity and string theory moduli


  We calculate the scalar potential of supersymmetric QCD (in the regime N_f <
N_c) coupled to N=1 supergravity with moduli-dependent gauge kinetic function
and masses. The gauge dynamics are described by the
Taylor-Veneziano-Yankielowicz superpotential for composite effective fields.
The potential can be expanded about the ``truncated'' point in the gaugino and
matter condensate directions in order to find corrections to the globally
supersymmetric minimum. The results are relevant to the phenomenology of
supersymmetry-breaking in string-inspired supergravity models, and also to
recent work on domain walls in SQCD.

</DOC>
<DOC>
<DOCNO> 122704 </DOCNO>
The eclipsing bursting X-ray binary EXO 0748-676 revisited by XMM-Newton


  The bright eclipsing and bursting low-mass X-ray binary EXO 0748-676 has been
observed at several occasions by XMM-Newton during the initial calibration and
performance verification (CAL/PV) phase. We present here the results obtained
from observations with the EPIC cameras. Apart from several type-I X-ray
bursts, the source shows a high degree of variability with the presence of soft
flares. The wide energy coverage and high sensitivity of XMM-Newton allows for
the first time a detailed description of the spectral variability.
  The source is found to be the superposition of a central (~2 10^8 cm)
Comptonized emission, most probably a corona surrounding the inner edge of an
accretion disk, associated with a more extended (~3 10^10 cm) thermal halo at a
typical temperature of ~0.6 keV with an indication of non-solar abundances.
Most of the variations of the source can be accounted for by a variable
absorption affecting only the central comptonized component and reaching up to
NH ~1.3 10^23 cm^{-2}. The characteristics of the surrounding halo are found
compatible with an irradiated atmosphere of an accretion disc which intercepts
the central emission due to the system high inclination.

</DOC>
<DOC>
<DOCNO> 70075 </DOCNO>
Explicit SO(10) Supersymmetric Grand Unified Model


  A complete set of Higgs and matter superfields is introduced with
well-defined SO(10) properties and U(1) \times Z_2 \times Z_2 family charges
from which the Higgs and Yukawa superpotentials are constructed. The Higgs
fields solve the doublet-triplet splitting problem, while the structures of the
four Dirac fermion mass matrices obtained involve just six effective Yukawa
operators. The right-handed Majorana matrix, M_R, arises from one Higgs field
coupling to several pairs of superheavy conjugate neutrino singlets. In terms
of 10 input parameters to the mass matrices, the model accurately yields the 20
masses and mixings of the lightest quarks and leptons, as well as the masses of
the 3 heavy right-handed neutrinos. The bimaximal atmospheric and solar
neutrino vacuum solutions are favored in this simplest version with a moderate
hierarchy in M_R. The large mixing angle MSW solution is obtainable, on the
other hand, with a considerably larger hierarchy in M_R which is also necessary
to obtain baryogenesis through the leptogenesis mechanism.

</DOC>
<DOC>
<DOCNO> 68090 </DOCNO>
Theorems on the Renormalization Group Evolution of Quark Yukawa


  We analyze the two loop renormalization group equations in the standard model
and its extensions for the coupling constants and the quark Yukawa couplings.
The key point of our analysis is the observed hierarchy of the quark masses and
the CKM matrix. For the one loop evolution we find the explicit solution for
the evolution of the Yukawa couplings and show the following: 1. the CKM matrix
depends on the energy on only one function of energy; 2. the ratios of the down
quark masses depend on the energy through the same function as the CKM matrix;
3. the diagonalizing matrices of the biunitary transformation of the up quarks
are energy independent. Next we give the explicit form of the two loop
corrections to the evolution of the quark Yukawa couplings and show that the
relative corrections are of the order (\lambda ^{4}) for the quark Yukawa
couplings and of the order (\lambda ^{5}) for the CKM matrix. Finally we give
the equations of the one loop evolution of the squares of the matrix elements
of the CKM matrix and their explicit solution.

</DOC>
<DOC>
<DOCNO> 117681 </DOCNO>
On the Determination of Star Formation Rates in Evolving Galaxy


  The redshift dependence of the luminosity density in certain wavebands (e.g.
UV and H-alpha) can be used to infer the history of star formation in the
populations of galaxies producing this luminosity. This history is a useful
datum in studies of galaxy evolution. It is therefore important to understand
the errors that attend the inference of star formation rate densities from
luminosity densities. This paper explores the self-consistency of star
formation rate diagnostics by reproducing commonly used observational
procedures in a model with known galaxy populations, evolutionary histories and
spectral emission properties. The study reveals a number of potential sources
of error in the diagnostic processes arising from the differential evolution of
different galaxy types. We argue that multi-wavelength observations can help to
reduce these errors.

</DOC>
<DOC>
<DOCNO> 12076 </DOCNO>
Money and Goldstone modes


  Why is ``worthless'' fiat money generally accepted as payment for goods and
services? In equilibrium theory, the value of money is generally not
determined: the number of equations is one less than the number of unknowns, so
only relative prices are determined. In the language of mathematics, the
equations are ``homogeneous of order one''. Using the language of physics, this
represents a continuous ``Goldstone'' symmetry. However, the continuous
symmetry is often broken by the dynamics of the system, thus fixing the value
of the otherwise undetermined variable. In economics, the value of money is a
strategic variable which each agent must determine at each transaction by
estimating the effect of future interactions with other agents. This idea is
illustrated by a simple network model of monopolistic vendors and buyers, with
bounded rationality. We submit that dynamical, spontaneous symmetry breaking is
the fundamental principle for fixing the value of money. Perhaps the continuous
symmetry representing the lack of restoring force is also the fundamental
reason for large fluctuations in stock markets.

</DOC>
<DOC>
<DOCNO> 100972 </DOCNO>
Remarks on Quantum Physics and Noncommutative Geometry


  The "quantum-event / prime ideal in a category/ noncommutative-point"
alternative to "classical-event / commutative prime ideal/ point" is suggested.
 Ideals in additive categories, prime spectra and representation of quivers are
considered as mathematical tools appropriate to model quantum mechanics. The
space-time framework is to be reconstructed from the spectrum of the path
category of a quiver.
 The interference experiment is considered as an example.

</DOC>
<DOC>
<DOCNO> 116593 </DOCNO>
Photon sensitivity of superheated drop at room temperature


  It has been reported so far that superheated drop detector made of R-12 at
room temperature are sensitive to neutrons yet insensitive to photons. This
property makes its use as one of the most useful neutron dosimeter. The photon
sensitivity of R12 at room temperature when exposed to 59.54kev photons
obtained from radioactive Am has been noted for the first time in our
laboratory. This discovery is important nt only from the point of view of basic
science but more important to the users of R12 in neutron dosimetry to take
note of this in assessing the neutron dose correctly.

</DOC>
<DOC>
<DOCNO> 69751 </DOCNO>
Constraining the free parameter of the high parton density effects


  The high density parton effects are strongly dependent of the spatial gluon
distribution within the proton, with radius $R$, which cannot be derived from
perturbative QCD. In this paper we assume that the unitarity corrections are
present in the HERA kinematical region and constrain the value of $R$ using the
data for the proton structure function and its slope. We obtain that the gluons
are not distributed uniformly in the whole proton disc, but behave as
concentrated in smaller regions.

</DOC>
<DOC>
<DOCNO> 13343 </DOCNO>
Real-Time-RG Analysis of the Dynamics of the Spin-Boson Model


  Using a real-time renormalization group method we determine the complete
dynamics of the spin-boson model with ohmic dissipation for coupling strengths
$\alpha\lesssim 0.1-0.2$. We calculate the relaxation and dephasing time, the
static susceptibility and correlation functions. Our results are consistent
with quantum Monte Carlo simulations and the Shiba relation. We present for the
first time reliable results for finite cutoff and finite bias in a regime where
perturbation theory in $\alpha$ or in tunneling breaks down. Furthermore, an
unambigious comparism to results from the Kondo model is achieved.

</DOC>
<DOC>
<DOCNO> 120164 </DOCNO>
Extremely red galaxies: age and dust degeneracy solved ?


  The extremely red galaxies (ERGs) are defined in terms of their very red
optical-to-near IR colours (as R-K>5 or I-K>4). Originally this selection was
aimed at selecting old (> 1 Gyr) passively evolving elliptical galaxies at
intermediate redshift (1<z<2), but it was soon discovered that young
star-forming dusty galaxies can show similar colours and therefore be selected
in the same surveys. It is crucial to distinguish between these two populations
because they have very different consequences on the models of galaxy
formation. Here we show that old ellipticals and dusty starburst are expected
to show different colours in the (I-K) vs. (J-K) diagram for redshift range
1<z<2, providing thus a useful tool to classify ERGs in large samples up to
K<20. This is mainly due to the fact that old galaxies at these redshifts have
a strong 4000 ang. break at lambda<1.2 mic. (J band), while dusty galaxies show
a smoother spectral energy distributions and therefore redder J-K colours. We
discuss this difference in detail both in the framework of the stellar
population synthesis models and by using observed spectra. The selection
criterion is also compared with the properties of ERGs of known nature. We also
show that this colour selection criterion is also useful to separate the ERGs
from brown dwarf stars showing similar optical-to-IR colours.

</DOC>
<DOC>
<DOCNO> 119244 </DOCNO>
A Jet Model for the Afterglow Emission from GRB000301C


  We present broad-band radio observations of the afterglow of GRB000301C,
spanning from 1.4 to 350 GHz for the period of 3 to 83 days after the burst.
This radio data, in addition to measurements at the optical bands, suggest that
the afterglow arises from a collimated outflow, i.e. a jet. To test this
hypothesis in a self-consistent manner, we employ a global fit and find that a
model of a jet, expanding into a constant density medium (ISM+jet), provides
the best fit to the data. A model of the burst occurring in a wind-shaped
circumburst medium (wind-only model) can be ruled out, and a wind+jet model
provides a much poorer fit of the optical/IR data than the ISM+jet model. In
addition, we present the first clear indication that the reported fluctuations
in the optical/IR are achromatic with similar amplitudes in all bands, and
possibly extend into the radio regime. Using the parameters derived from the
global fit, in particular a jet break time, t_{jet}=7.5 days, we infer a jet
opening angle of \theta=0.2, and consequently the estimate of the emitted
energy in the GRB itself is reduced by a factor of 50 relative to the isotropic
value, giving E=1.1 \times 10^{51} ergs.

</DOC>
<DOC>
<DOCNO> 119721 </DOCNO>
Simulation of the Spherically Symmetric Stellar Core Collapse, Bounce,


  With exact three-flavor Boltzmann neutrino transport, we simulate the stellar
core collapse, bounce, and postbounce evolution of a 13 solar mass star in
spherical symmetry, the Newtonian limit, without invoking convection. In the
absence of convection, prior spherically symmetric models, which implemented
approximations to Boltzmann transport, failed to produce explosions. We are
motivated to consider exact transport to determine if these failures were due
to the transport approximations made and to answer remaining fundamental
questions in supernova theory. The model presented here is the first in a
sequence of models beginning with different progenitors. In this model, a
supernova explosion is not obtained. We discuss the ramifications of our
results for the supernova mechanism.

</DOC>
<DOC>
<DOCNO> 179008 </DOCNO>
Constructing Point Form Mass Operators from Interaction Lagrangians


  Starting from an interaction Lagrangian formed out of local fields, an
interacting four-momentum operator is constructed by integrating the
interaction Lagrangian over the forward hyperboloid. Such a four-momentum
operator has the property that the components commute among themselves;
however, when the Fock space on which the four-momentum operator acts is
truncated, the components no longer commute among themselves. By modifying
matrix elements of the four-momentum operator on the truncated space,
Bakamjian-Thomas mass operatorsare constructed which restore the Poincare
relations. Examples for a simple Lagrangian are given.

</DOC>
<DOC>
<DOCNO> 11787 </DOCNO>
Nuclear Spin-Ordering Due to Correlated Atomic Motion in bcc $^3$He


  We propose a new way to treat nuclear magnetism of solid $^{3}$He. We argue
that the magnetic interaction arises indirectly as a consequence of correlated
zero-point motion of the ions. This motion lowers the energy of the ground
state, and results in a coherent state of oscillating electric dipoles.
Distortion of the electronic wavefunctions leads to hyperfine magnetic
interactions with the nuclear spin.
 Our model describes both the phonon spectra and the nuclear magnetic ordering
of bcc $^{3}$He using a single parameter, the dipolar interaction energy
$E_{0}$. The model yields correctly both the u2d2 symmetry of the ordered phase
and the volume dependence of the magnetic interaction.

</DOC>
<DOC>
<DOCNO> 151016 </DOCNO>
Brane Worlds, the Cosmological Constant and String Theory


  We argue that traditional methods of compactification of string theory make
it very difficult to understand how the cosmological constant becomes zero.
String inspired models can give zero cosmological constant after fine tuning
but since string theory has no free parameters it is not clear that this is
allowed. Brane world scenarios on the other hand while they do not answer the
question as to why the cosmological constant is zero do actually allow a choice
of integration constants that permit flat four space solutions. In this paper
we discuss gauged supergravity realizations of such a world. To the extent that
this starting point can be considered a low energy effective action of string
theory (and there is some recent evidence supporting this) our model may be
considered a string theory realization of this scenario.

</DOC>
<DOC>
<DOCNO> 8796 </DOCNO>
Solvable model of a polymer in random media with long ranged disorder


  We present an exactly solvable model of a Gaussian (flexible) polymer chain
in a quenched random medium. This is the case when the random medium obeys very
long range quadratic correlations. The model is solved in $d$ spatial
dimensions using the replica method, and practically all the physical
properties of the chain can be found. In particular the difference between the
behavior of a chain that is free to move and a chain with one end fixed is
elucidated. The interesting finding is that a chain that is free to move in a
quadratically correlated random potential behaves like a free chain with $R^2
\sim L$, where $R$ is the end to end distance and $L$ is the length of the
chain, whereas for a chain anchored at one end $R^2 \sim L^4$. The exact
results are found to agree with an alternative numerical solution in $d=1$
dimensions. The crossover from long ranged to short ranged correlations of the
disorder is also explored.

</DOC>
<DOC>
<DOCNO> 85083 </DOCNO>
Cosmic Rays and the Structure of Space-Time


  Even a fundamental symmetry like Lorentz Invariance is an experimental fact
and must be experimentally verified. We show that the study of the interactions
of Cosmic Rays with universal diffuse background radiation can provide very
stringent tests of this symmetry. The interactions we consider are the ones
characterized by well defined energy thresholds whose energy position can be
predicted on the basis of Special Relativity. We argue that the experimental
verification of these thresholds can address the physics of supra-Planckian
scales.

</DOC>
<DOC>
<DOCNO> 119426 </DOCNO>
The morphology of the Magellanic Clouds revealed by stars of different


  The spatial distribution of sources populating different regions of the
colour-magnitude diagram (I-J, I) extracted from the DENIS catalogue towards
the Magellanic Clouds (DCMC -- Cioni et al. 2000) reveal significantly
different morphologies. Each region is associated to a different age group. The
Large Magellanic Cloud (LMC) shows an extended circular shape with a prominent,
off center bar, a nucleus and irregular spiral arms. The Small Magellanic Cloud
shows a perturbated structure with a prominent central concentration of stars.
Old and young populations are offset from one another.

</DOC>
<DOC>
<DOCNO> 151475 </DOCNO>
The Superfield Formalism Applied to the Noncommutative Wess-Zumino Model


  We introduce the notion of superoperators on noncommutative R^4 and
re-investigate in the framework of superfields the noncommutative Wess-Zumino
model as a quantum field theory. In a highly efficient manner we are able to
confirm the result that this model is renormalizable to all orders.

</DOC>
<DOC>
<DOCNO> 117866 </DOCNO>
H2 emission from CRL 618


  We present a complete study of the H2 infrared emission, including the pure
rotational lines, of the proto Planetary Nebulae CRL 618 with the ISO SWS. A
large number of lines are detected. The analysis of our observations shows: (i)
an OTP ratio very different from the classical value of 3, probably around
1.76-1.87; (ii) a stratification of the emitting region, and more precisely
different regions of emission, plausibly located in the lobes, in an
intermediate zone, and close to the torus; (iii) different excitation
mechanisms, collisions and fluorescence.

</DOC>
<DOC>
<DOCNO> 9084 </DOCNO>
Symmetry Dependence of Localization in Quasi- 1- dimensional Disordered


  The crossover in energy level statistics of a quasi-1-dimensional disordered
wire as a function of its length L is used, in order to derive its averaged
localization length, without magnetic field, in a magnetic field and for
moderate spin orbit scattering strength. An analytical function of the magnetic
field for the local level spacing is obtained, and found to be in excellent
agreement with the magnetic field dependent activation energy, recently
measured in low-mobility quasi-one-dimensional wires\cite{khavin}. This formula
can be used to extract directly and accurately the localization length from
magnetoresistance experiments. In general, the local level spacing is shown to
be proportional to the excitation gap of a virtual particle, moving on a
compact symmetric space.

</DOC>
<DOC>
<DOCNO> 151129 </DOCNO>
Solitons and black holes in non-Abelian Einstein-Born-Infeld theory


  Recently it was shown that the Born-Infeld-type modification of the
quadratic Yang-Mills action gives rise to classical particle-like solutions in
the flat space which have a striking similarity with the Bartnik-McKinnon
solutions known in the gravity coupled Yang-Mills theory. We show that both
families are continuously related within the framework of the
Einstein-Born-Infeld theory through interpolating sequences of parameters. We
also investigate an internal structure of the associated black holes. It is
found that the Born-Infeld non-linearity leads to a drastic modification of
the black hole interior typical for the usual Yang-Mills theory. In the latter
case a generic solution exhibits violent metric oscillations near the
singularity. In the Born-Infeld case a generic interior solution is smooth, the
metric has the standard Schwarzschild type singularity, and we did not observe
internal horizons. Such smoothing of the 'violent' EYM singularity may be
interpreted as a result of quantum effects.

</DOC>
<DOC>
<DOCNO> 68290 </DOCNO>
A Path Integral Approach to Inclusive Processes


  The single-particle inclusive differential cross-section for a reaction
$a+b\to c+X$ is written as the imaginary part of a correlation function in a
for ward scattering amplitude for $a+b\to a+b$ in a modified effective theory.
In this modified theory the interaction Hamiltonian $\tilde H_I$ equals $H_I$
in the original theory up to a certain time. Then there is a sign change and
$\tilde H_I$ becomes nonlocal. This is worked out in detail for scalar field
models and for QED plus the abelian gluon model. A suitable path integral for
direct calculations of inclusive cross sections is presented.

</DOC>
<DOC>
<DOCNO> 178586 </DOCNO>
The Dynamical Dipole Mode in Dissipative Heavy Ion Collisions


  We study the effect of a direct Giant Dipole Resonance ($GDR$) excitation in
intermediate dinuclear systems with exotic shape and charge distributions
formed in charge asymmetric fusion entrance channels. A related enhancement of
the $GDR$ gamma yield in the evaporation cascade of the fused nucleus is
expected. The dynamical origin of such $GDR$ extra strength will show up in a
characteristic anisotropy of the dipole gamma-emission. A fully microscopic
analysis of the fusion dynamics is performed with quantitative predictions of
the $GDR$ photon yield based on a dynamics- statistics coupling model. In
particular we focus our attention on the energy and mass dependence of the
effect.
 We suggest a series of new experiments, in particular some optimal entrance
channel conditions. We stress the importance of using the new available
radioactive beams.

</DOC>
<DOC>
<DOCNO> 13566 </DOCNO>
Low-dimensional quantum spin systems


  Low-dimensional quantum spin systems are interacting many body systems for
which several rigorous results are known. Powerful techniques like the Bethe
Ansatz provide exact knowledge of the ground state energy and low-lying
excitation spectrum. A large number of compounds exists which can effectively
be described as low-dimensional spin systems. Thus many of the rigorous results
are also of experimental relevance. In this Lecture Note, an introduction is
given to quantum spin systems and the rigorous results known for such systems.
Some general theorems and exactly-solvable models are discussed. An elementary
introduction to the Bethe Ansatz technique is given.

</DOC>
<DOC>
<DOCNO> 99887 </DOCNO>
Ricci Curvature, Minimal Volumes, and Seiberg-Witten Theory


  We derive new, sharp lower bounds for certain curvature functionals on the
space of Riemannian metrics of a smooth compact 4-manifold with a non-trivial
Seiberg-Witten invariant. These allow one, for example, to exactly compute the
infimum of the L2-norm of Ricci curvature for all complex surfaces of general
type. We are also able to show that the standard metric on any complex
hyperbolic 4-manifold minimizes volume among all metrics satisfying a
point-wise lower bound on sectional curvature plus suitable multiples of the
scalar curvature. These estimates also imply new non-existence results for
Einstein metrics.

</DOC>
<DOC>
<DOCNO> 70342 </DOCNO>
Flow equations for quark-gluon interactions in light-front QCD


  The flow-equation method of continuous unitary transformations is used to
eliminate the minimal quark-gluon interaction in the light-front quantized QCD
Hamiltonian. The coupled differential equations in the two lowest Fock sectors
correspond to the renormalization of the light-front gluon mass and the
generation of an effective quark-antiquark (as well as gluon-gluon)
interaction. The original gauge field coupling is completely eliminated, even
in the presence of degenerate states connected by this interaction. Further, a
more singular $1/q^4$ behavior for the quark and gluon effective interactions
at small gluon momenta is obtained, due to the asymptotic behavior of the
effective gluon mass for small cutoff. We discuss the consequences of this
asymptotic behavior and possible confinement implications.

</DOC>
<DOC>
<DOCNO> 84870 </DOCNO>
Time in Quantum Geometrodynamics


  We revisit the issue of time in quantum geometrodynamics and suggest a
quantization procedure on the space of true dynamic variables. This procedure
separates the issue of quantization from enforcing the constraints caused by
the general covariance symmetries. The resulting theory, unlike the standard
approach, takes into account the states that are off shell with respect to the
constraints, and thus avoids the problems of time. In this approach, quantum
geometrodynamics, general covariance, and the interpretation of time emerge
together as parts of the solution of the total problem of geometrodynamic
evolution.

</DOC>
<DOC>
<DOCNO> 70522 </DOCNO>
Gravity in Randall-Sundrum Brane World Revisited


  We point out some subtleties with gauge fixings (which sometimes include the
so-called ``brane bending'' effects) typically used to compute the graviton
propagator on the Randall-Sundrum brane. In particular, the brane, which has
non-vanishing tension, explicitly breaks some part of the diffeomorphisms, so
that there are subtleties arising in going to, say, the axial gauge or the
harmonic gauge in the presence of (non-conformal) matter localized on the
brane. We therefore compute the graviton propagator in the gauge where only the
graviphoton fluctuations are set to zero (the diffeomorphisms necessary for
this gauge fixing are intact), but the graviscalar component is untouched. We
point out that in the Gaussian normal coordinates (where the graviscalar
component vanishes on the brane) the graviton propagator blows up in the
ultra-violet near the brane. In fact, the allowed gauge transformations, which
do not lead to such ultra-violet behavior of the graviton propagator, are such
that the coupling of the graviscalar to the brane matter cannot be gauged away
in the ultra-violet. Because of this, at the quantum level, where we expect
various additional terms to be generated in the brane world-volume action
including those involving the graviscalar, fine-tuning (which is independent of
that for the brane cosmological constant) is generically required to preserve
consistent coupling between bulk gravity and brane matter. We also reiterate
that in such warped backgrounds higher curvature terms in the bulk are
generically expected to delocalize gravity.

</DOC>
<DOC>
<DOCNO> 10030 </DOCNO>
Quantum-critical superconductivity in underdoped cuprates


  We argue that the pseudogap phase may be an attribute of the non-BCS pairing
of quantum-critical, diffusive fermions near the antiferromagnetic quantum
critical point. We derive and solve a set of three coupled Eliashberg-type
equations for spin-mediated pairing and show that in some $T$ range below the
pairing instability, there is no feedback from superconductivity on fermionic
excitations, and fermions remain diffusive despite of the pairing. We conject
that in this regime, fluctuations of the pairing gap destroy the
superconducting condensate but preserve the leading edge gap in the fermionic
spectral function.

</DOC>
<DOC>
<DOCNO> 9425 </DOCNO>
Spin-triplet superconductivity in repulsive Hubbard models with


  We propose that spin-fluctuation-mediated spin-triplet superconductivity may
be realized in repulsive Hubbard models with disconnected Fermi surfaces. The
idea is confirmed for Hubbard models on triangular (dilute band filling) and
honeycomb (near half-filling) lattices using fluctuation exchange
approximation, where triplet pairing order parameter with f-wave symmetry is
obtained. Possible relevance to real superconductors is suggested.

</DOC>
<DOC>
<DOCNO> 12393 </DOCNO>
Interaction-induced chaos in a two-electron quantum-dot system


  A quasi-one-dimensional quantum dot containing two interacting electrons is
analyzed in search of signatures of chaos. The two-electron energy spectrum is
obtained by diagonalization of the Hamiltonian including the exact Coulomb
interaction. We find that the level-spacing fluctuations follow closely a
Wigner-Dyson distribution, which indicates the emergence of quantum signatures
of chaos due to the Coulomb interaction in an otherwise non-chaotic system. In
general, the Poincar\'e maps of a classical analog of this quantum mechanical
problem can exhibit a mixed classical dynamics. However, for the range of
energies involved in the present system, the dynamics is strongly chaotic,
aside from small regular regions. The system we study models a realistic
semiconductor nanostructure, with electronic parameters typical of gallium
arsenide.

</DOC>
<DOC>
<DOCNO> 120801 </DOCNO>
Galaxy Spin Statistics and Spin-Density Correlation


  We present a theoretical study of galaxy spin correlation statistics, with
detailed technical derivations. We also find an expression for the spin-density
cross-correlation, and apply that to the Tully galaxy catalog. The
observational results appear qualitatively consistent with the theoretical
predictions, yet the error bars are still large. However, we expect that
currently ongoing large surveys such as the Sloan Digital Sky survey (SDSS)
will enable us to make a precision measurement of these correlation statistics
in the near future. These intrinsic galaxy alignments are expected to dominate
over the weak lensing signal in SDSS, and we present the detailed algorithms
for the density reconstruction for this case.
  These observables are tracers of the galaxy-gravity interaction, which may
provide us deeper insights into the galaxy formation and large scale matter
distribution as well.

</DOC>
<DOC>
<DOCNO> 8507 </DOCNO>
Congested Traffic States in Empirical Observations and Microscopic


  We present data from several German freeways showing different kinds of
congested traffic forming near road inhomogeneities, specifically lane
closings, intersections, or uphill gradients. The states are localized or
extended, homogeneous or oscillating. Combined states are observed as well,
like the coexistence of moving localized clusters and clusters pinned at road
inhomogeneities, or regions of oscillating congested traffic upstream of nearly
homogeneous congested traffic. The experimental findings are consistent with a
recently proposed theoretical phase diagram for traffic near on-ramps [D.
Helbing, A. Hennecke, and M. Treiber, Phys. Rev. Lett. {\bf 82}, 4360 (1999)].
We simulate these situations with a novel continuous microscopic single-lane
model, the ``intelligent driver model'' (IDM), using the empirical boundary
conditions. All observations, including the coexistence of states, are
qualitatively reproduced by describing inhomogeneities with local variations of
one model parameter.
  We show that the results of the microscopic model can be understood by
formulating the theoretical phase diagram for bottlenecks in a more general
way. In particular, a local drop of the road capacity induced by parameter
variations has practically the same effect as an on-ramp.

</DOC>
<DOC>
<DOCNO> 70372 </DOCNO>
Natural Mass Generation for the Sterile Neutrino


  We point out that there is a serious cosmological problem in the
supersymmetric standard model if a sterile neutrino is responsible for the
solar neutrino oscillation, and propose a possible solution to this problem. We
show that our solution induces naturally a mass of order 10^{-4} eV for the
sterile neutrino, which is deeply related to the mechanism of supersymmetry
breaking.

</DOC>
<DOC>
<DOCNO> 150933 </DOCNO>
Tachyon Condensation on a non-BPS D-brane


  We extend the recent computation of the tachyon potential by Berkovits, Sen
and Zwiebach by including level two fields and keeping up to level four terms
in the action. We find 90.5% of the expected result.

</DOC>
<DOC>
<DOCNO> 68226 </DOCNO>
Modification of Z Boson Properties in Quark-Gluon Plasma


  We calculate the change in the effective mass and width of a Z boson in the
environment of a quark-gluon plasma under the conditions expected in Pb-Pb
collisions at the LHC. The change in width is predicted to be only about 1 MeV
at a temperature of 1 GeV, compared to the natural width of 2490$\pm$7 MeV. The
mass shift is even smaller. Hence no observable effects are to be expected.

</DOC>
<DOC>
<DOCNO> 80586 </DOCNO>
Lorentzian and Euclidean Quantum Gravity - Analytical and Numerical


  We review some recent attempts to extract information about the nature of
quantum gravity, with and without matter, by quantum field theoretical methods.
More specifically, we work within a covariant lattice approach where the
individual space-time geometries are constructed from fundamental simplicial
building blocks, and the path integral over geometries is approximated by
summing over a class of piece-wise linear geometries. This method of
``dynamical triangulations'' is very powerful in 2d, where the regularized
theory can be solved explicitly, and gives us more insights into the quantum
nature of 2d space-time than continuum methods are presently able to provide.
It also allows us to establish an explicit relation between the Lorentzian- and
Euclidean-signature quantum theories. Analogous regularized gravitational
models can be set up in higher dimensions. Some analytic tools exist to study
their state sums, but, unlike in 2d, no complete analytic solutions have yet
been constructed. However, a great advantage of our approach is the fact that
it is well-suited for numerical simulations. In the second part of this review
we describe the relevant Monte Carlo techniques, as well as some of the
physical results that have been obtained from the simulations of Euclidean
gravity. We also explain why the Lorentzian version of dynamical triangulations
is a promising candidate for a non-perturbative theory of quantum gravity.

</DOC>
<DOC>
<DOCNO> 83123 </DOCNO>
Fuzzy Approaches to Abductive Inference


  This paper proposes two kinds of fuzzy abductive inference in the framework
of fuzzy rule base. The abductive inference processes described here depend on
the semantic of the rule. We distinguish two classes of interpretation of a
fuzzy rule, certainty generation rules and possible generation rules. In this
paper we present the architecture of abductive inference in the first class of
interpretation. We give two kinds of problem that we can resolve by using the
proposed models of inference.

</DOC>
<DOC>
<DOCNO> 9687 </DOCNO>
Temperature dependence of the nematic anchoring energy:mean field


  In the mean field approximation, we evaluate the temperature dependence of
the anchoring energy strength of a nematic liquid crystal in contact with a
solid substrate due to thermal fluctuations. Our study is limited to the weak
anchoring case, where the microscopic surface energy is small with respect to
the mean field energy due to the nematic phase. We assume furthermore that the
physical properties of the substrate can be considered temperature independent
in the range of the nematic phase. According to the thermodynamical
perturbative approach, the macroscopic surface energy is deduced by averaging
the microscopic one, with a density matrix containing only the nematic mean
field. We show that the thermal renormalization of the anchoring energy
coefficients is proportional to the generalized nematic order parameters.

</DOC>
<DOC>
<DOCNO> 121379 </DOCNO>
The black-hole masses of Seyfert galaxies and quasars


  The central black-hole masses of a sample of 30 luminous quasars are
estimated using H-beta FWHM measurements from a combination of new and
previously-published nuclear spectra. The quasar black-hole mass estimates are
combined with reverberation-mapping measurements for a sample of Seyfert
galaxies (Wandel 1999) in order to study AGN black-hole masses over a wide
range in nuclear luminosity. It is found that black-hole mass and bulge
luminosity are well correlated and follow a relation consistent with that
expected if black-hole and bulge mass are directly proportional. Contrary to
the results of Wandel (1999) no evidence is found that Seyfert galaxies follow
a different Mblack-Mbulge relation to quasars. However, the black-hole mass
distributions of the radio-loud and radio-quiet quasar sub-samples are found to
be significantly different, with the median black-hole mass of the radio-loud
quasars a factor of three larger than their radio-quiet counterparts. Finally,
utilizing the elliptical galaxy fundamental plane to provide stellar velocity
dispersion estimates, a comparison is performed between the virial H-beta
black-hole mass estimates and those of the Mblack-sigma correlations of
Gebhardt et al. (2000a) and Merritt & Ferrarese (2000). With the disc-like
geometry of the broad-line region adopted in this paper, the virial H-beta
black-hole masses indicate that the correct normalization of the black-hole vs.
bulge mass relation is Mblack=0.0025Mbulge, while the standard assumption of
purely random broad-line velocities leads to Mblack=0.0008Mbulge. The
normalization of Mblack=0.0025Mbulge provided by the disc model is in
remarkably good agreement with that inferred for our quasar sample using the
(completely independent) Mblack-sigma correlations.

</DOC>
<DOC>
<DOCNO> 120909 </DOCNO>
Radio Jet-blown Neutral Hydrogen Supershells in Spiral Galaxies?


  Taking a clue from the pair of HI supershells found in the Scd galaxy NGC
3556 (M 108), we propose a new mechanism for the origin of HI supershells in
gas-rich massive galaxies. In this scenario, the two supershells were inflated
out of the neutral hydrogen disk due to the localised flaring of a pair of
radio lobes formed by the jets ejected from the nucleus during an active phase
about 10^7 years ago, but have faded away by now. It is shown that the salient
features of this supershell pair, such as their symmetrical locations about the
galactic centre, the anomalously large energy requirements, the large
galactocentric distances, as well as the Z-symmetric hemispherical shapes, find
a more natural explanation in terms of this scenario, as compared to the
standard models which postulate either a massive starburst, or the infall of
external gas clouds. Other possible implications of this hypothesis are briefly
discussed.

</DOC>
<DOC>
<DOCNO> 100664 </DOCNO>
On the moduli space of classical dynamical r-matrices


  We define and study the moduli space of classical dynamical r-matrices
associated to a Lie algebra g and a subalgebra l of g. As opposed to the
previous papers q-alg/9703040 and q-alg/9706017 we do not make any
commutativity assumption on the subalgebra l. We extend the notion of
gauge-transformation to this setting and show that, under some technical
conditions, the space of dynamical r-matrices modulo gauge-transformations is
isomorphic to an explicitly given affine variety.

</DOC>
<DOC>
<DOCNO> 85102 </DOCNO>
Regular charged black hole with a charged de Sitter core


  We show that there is a class of regular charged black hole with a charged de
Sitter core similar to the de Sitter-Schwarzschild black hole. One can show
that the total energy momentum tensor for the static and spherically symmetric
photon field can be made conserved even the Coulomb like energy momentum tensor
for photon is not conserved alone. Possible impact and the numerical solutions
of the charged black hole will be shown in this paper.

</DOC>
<DOC>
<DOCNO> 102540 </DOCNO>
Discrete Morse Complexes


  We investigate properties of the set of discrete Morse functions on a
simplicial complex as defined by Forman. It is not difficult to see that the
pairings of discrete Morse functions of a finite simplicial complex again form
a simplicial complex, the discrete Morse complex. It turns out that several
known results from combinatorial topology and enumerative combinatorics, which
previously seemed to be unrelated, can be re-interpreted in the setting of
these discrete Morse complexes.

</DOC>
<DOC>
<DOCNO> 118507 </DOCNO>
The CFH Optical PDCS survey (COP) I: The Data


  This paper presents and gives the COP (COP: CFHT Optical PDCS; CFHT:
Canada-France-Hawaii Telescope; PDCS: Palomar Distant Cluster Survey) survey
data. We describe our photometric and spectroscopic observations with the MOS
multi-slit spectrograph at the CFH telescope. A comparison of the photometry
from the PDCS (Postman et al. 1996) catalogs and from the new images we have
obtained at the CFH telescope shows that the different magnitude systems can be
cross-calibrated. After identification between the PDCS catalogues and our new
images, we built catalogues with redshift, coordinates and V, I and
Rmagnitudes. We have classified the galaxies along the lines of sight into
field and structure galaxies using a gap technique (Katgert et al. 1996). In
total we have observed 18 significant structures along the 10 lines of sight.

</DOC>
<DOC>
<DOCNO> 67990 </DOCNO>
Is $f_1(1420)$ the partner of $f_1(1285)$ in the $^3P_1$ $q\bar{q}$


  Based on a $2\times 2$ mass matrix, the mixing angle of the axial vector
states $f_1(1420)$ and $f_1(1285)$ is determined to be $51.5^{\circ}$, and the
theoretical results about the decay and production of the two states are
presented. The theoretical results are in good agreement with the present
experimental results, which suggests that $f_1(1420)$ can be assigned as the
partner of $f_1(1285)$ in the $^3P_1$ $q\bar{q}$ nonet. We also suggest that
the existence of $f_1(1510)$ needs further experimental confirmation.

</DOC>
<DOC>
<DOCNO> 122602 </DOCNO>
Period-Luminosity-Colour distribution and classification of Galactic


  The kinematic and Period-Luminosity-Colour distribution of O-rich Long-Period
Variable stars of the solar neighbourhood is interpreted in terms of pulsation
modes, masses and metallicities. It is first shown that, because of input
physics imperfections, the periods and mean colours derived from the existing
linear and nonlinear nonadiabatic models must significantly depart from the
actual behaviour of the stars. As a consequence systematic corrections have to
be applied, as a first approximation, to our linear model grid. These free
parameters, as well as the mixing length, are calibrated on the LPVs of the LMC
and of some globular clusters, assuming a mean mass of one solar mass for the
LMC Mira-like stars. Then, the masses and metallicities corresponding to the
four kinematic/photometric populations of local LPVs are evaluated. The
possibility of a varying mixing-length parameter is discussed and taken into
account.

</DOC>
<DOC>
<DOCNO> 118074 </DOCNO>
X-ray observation of the super-luminal quasar 4C+73.18 (1928+738) by


  The results of an X-ray observation of the nearby core-dominated, super-
luminal quasar 4C+73.18 (1928+738) with ASCA are reported. Variations of the
1-10keV flux on time-scales of the order of 10 hours were found while the
0.5-1keV flux remained almost unchanged. The quasar shows a curved spectrum in
the 0.8-10keV band, which can be modeled as a power law plus a soft component.
Both, the spectrum and the uncorrelated flux variations indicate the presence
of a soft X-ray excess, which might be the high-energy extension of the intense
UV bump emission found in this quasar. The hard X-ray emission is dominated by
the flat power law (photon index 1.1-1.5). The results are consistent with
models in which the hard X-rays are emitted from the relativistic jet. An iron
line emission as reported in a previous Ginga observation (Lawson & Turner
1997) was not detected. We suggest that the line detected by Ginga might be not
associated with the quasar. There are indications for a tentative weak emission
line-like feature around 1.25keV (1.63keV in the quasar frame) in both, the SIS
and GIS spectra. The energy is surprisingly close to that of an unexplained
line found in the flat-spectrum quasar PKS0637-752 by Yaqoob et al. (1998).

</DOC>
<DOC>
<DOCNO> 70563 </DOCNO>
2d Model Field Theories at Finite Temperature and Density


  In certain 1+1 dimensional field theoretic toy models, one can go all the way
from microscopic quarks via the hadron spectrum to the properties of hot and
dense baryonic matter in an essentially analytic way. This "miracle" is
illustrated through case studies of two popular large N models, the Gross-Neveu
and the 't Hooft model - caricatures of the Nambu-Jona-Lasinio model and real
QCD, respectively. The main emphasis will be on aspects related to spontaneous
symmetry breaking (discrete or continuous chiral symmetry, translational
invariance) and confinement.

</DOC>
<DOC>
<DOCNO> 120557 </DOCNO>
Advection-Dominated Accretion Onto Weakly-Magnetized White Dwarfs


  The boundary layers of weakly-magnetized white dwarfs (WDs) accreting at
rates <=10^16 g/s are radially extended, hot, optically-thin, and they advect
some of their internally-dissipated energy (Narayan & Popham 1993). Motivated
by this, I construct here idealized spectral models of an Advection-Dominated
Accretion Flow (ADAF) around a WD, for application to quiescent Dwarf Novae
(DN). The Bremsstrahlung cooling of the gas in the ADAF, with temperatures
ranging from a few keV to a few tens of keV, can account for the X-ray emission
properties of quiescent DN. If the energy advected by the flow is thermalized
in the WD atmosphere, the resulting emission from the entire stellar surface
(blackbody of temperature T_eff ~ 5 eV) outshines the X-ray luminosity
substantially. This extreme-UV component provides a flux in the 0.055-0.28 keV
band which is sufficient to power the strong HeII lambda4686 emission lines of
quiescent DN by photoionization of the disk material. Reprocessing of the ADAF
X-ray emission by a cold outer thin disk could also lead to an observable iron
Kalpha fluorescence emission line, which can be used to probe the geometry of
the accretion flow. Existing observational data indicate that the presence of
ADAFs in quiescent DN is not ubiquitous, while future observations, in
particular with the X-ray satellites Chandra and XMM-Newton, have the potential
to detect signatures of the hot flow in promising candidates.

</DOC>
<DOC>
<DOCNO> 7755 </DOCNO>
Casimir energy of a dilute dielectric ball with uniform velocity of


  The Casimir energy, free energy and Casimir force are evaluated, at arbitrary
finite temperature, for a dilute dielectric ball with uniform velocity of light
inside the ball and in the surrounding medium. In particular, we investigate
the classical limit at high temperature. The Casimir force found is repulsive,
as in previous calculations.

</DOC>
<DOC>
<DOCNO> 70130 </DOCNO>
Pseudovector mesons, hybrids and glueballs


  We consider glueball- (hybrid) meson mixing for the low-lying four
pseudovector states. The h_1'(1380) decays dominantly to K*K with some presence
in rho pi and omega eta. The newly observed h_1(1600) has a D- to S-wave width
ratio to omega eta which makes its interpretation as a conventional meson
unlikely. We predict the decay pattern of the isopartner conventional or hybrid
meson b_1(1650). A notably narrow s sbar partner h_1'(1810) is predicted.

</DOC>
<DOC>
<DOCNO> 178633 </DOCNO>
Faddeev Calculations of Proton-Deuteron Radiative Capture with Exchange


  pd capture processes at various energies have been analyzed based on
solutions of 3N-Faddeev equations and using modern NN forces. The application
of the Siegert theorem is compared to the explicit use of $\pi$- and
$\rho$-like exchange currents connected to the AV18 NN interaction. Overall
good agreement with cross sections and spin observables has been obtained but
leaving room for improvement in some cases. Feasibility studies for 3NF's
consistently included in the 3N continuum and the 3N bound state have been
performed as well.

</DOC>
<DOC>
<DOCNO> 102020 </DOCNO>
Annihilators of Ideals of Exterior Algebras


  The Orlik-Solomon algebra A of a matroid is isomorphic to the quotient of an
exterior algebra E by a defining ideal I. We find an explicit presentation of
the annihilator ideal of I or, equivalently, the E-module dual to A. As an
application of that we provide a necessary, combinatorial condition for the
algebra A to be quadratic. We show that this is stronger than matroid being
line-closed thereby resolving (negatively) a conjecture by Falk. We also show
that our condition is not sufficient for the quadraticity.

</DOC>
<DOC>
<DOCNO> 122081 </DOCNO>
A low global star formation rate in the rich galaxy cluster AC114 at


  We present the results of a wide-field survey for H-alpha emitting galaxies
in the cluster AC114 at z=0.32. Spectra centred on H-alpha at the cluster
redshift have been obtained for 586 galaxies to I~22 out to a radius around
2Mpc. At most, only ~10% of these were found to be H-alpha-emitting cluster
members. These objects are predominantly blue and of late-type spiral
morphology, consistent with them hosting star formation. However, ~65% of the
cluster members classified morphologically as spirals (with HST), have no
detectable H-alpha emission; star-formation and morphological evolution in
cluster galaxies appear to be largely decoupled. Changes in the H-alpha
detection rate and the strength of H-alpha emission with environment are found
to be weak within the region studied. Star formation within the cluster members
is also found to be strongly and uniformly suppressed, with the rates inferred
from the H-alpha emission not exceeding 4Mo/yr, and AC114's H-alpha luminosity
function being an order of magnitude below that observed for field galaxies at
the same redshift. None of the galaxies detected have the high star formation
rates associated with `starburst' galaxies; however, this may still be
reconciliable with the known (8+/-3%) fraction of `post-starburst' galaxies
within AC114, given the poorly determined but short lifetimes of starbursts and
the possibility that much of the associated star formation is obscured by dust.

</DOC>
<DOC>
<DOCNO> 101470 </DOCNO>
Fano hypersurfaces in weighted projective 4-spaces


  We determine the complete list of anticanonically embedded quasi smooth log
Fano 3-folds in weighted projective 4-spaces. This implies that the
Reid-Fletcher list of 95 types of anticanonically embedded quasi smooth
terminal Fano threefolds in weighted projective 4-spaces is complete. We also
prove that there are only finitely many families of quasi smooth Calabi-Yau
hypersurfaces in weighted projective spaces of any given dimension.

</DOC>
<DOC>
<DOCNO> 85549 </DOCNO>
Discrete structures in gravity


  Discrete approaches to gravity, both classical and quantum, are reviewed
briefly, with emphasis on the method using piecewise-linear spaces. Models of
3-dimensional quantum gravity involving 6j-symbols are then described, and
progress in generalising these models to four dimensions is discussed, as is
the relationship of these models in both three and four dimensions to
topological theories. Finally, the repercussions of the generalisations are
explored for the original formulation of discrete gravity using edge-length
variables.

</DOC>
<DOC>
<DOCNO> 69763 </DOCNO>
Dynamics and causality constraints


  The physical meaning and the geometrical interpretation of causality
implementation in classical field theories are discussed. Local causality are
kinematical constraints dynamically implemented via solutions of the field
equations, but in a limit of zero-distance from the field sources part of these
constraints carries a dynamical content that explains old problems of classical
electrodynamics away with deep implications to the nature of physical
interactions.

</DOC>
<DOC>
<DOCNO> 121658 </DOCNO>
Observations of Lyman-alpha Absorption in a Triple Quasar System


  We have obtained follow-up observations of the quasar pair LBQS 0107-025A,B
and new observations of the nearby quasar LBQS 0107-0232 with the Hubble Space
Telescope Faint Object Spectrograph. Extended wavelength coverage of LBQS
0107-025A and B using the G270H grating was also obtained. This triple system
is unique in providing sensitivity to coherent Ly-alpha absorption on
transverse scales of approximately 1 Mpc at z < 1. Monte Carlo simulations were
used to establish the confidence level for matches between absorption features
in different lines of sight as a function of velocity separation. Pairwise,
there are 8, 9, and 12 lines that match between spectra. Three instances of
matches between all three lines of sight were found with velocity separations
of less than 550 kms^-1. Two of the pairings have coincident lines within
|Delta v| < 200 kms^-1 that would occur with less than 10% probability by
chance. Taking into account the equivalent widths of the lines, one of these
triple coincidences is significant at the 99.99% confidence level, based on
Monte Carlo simulations with random line placements. Matches with strong lines
preferentially have small velocity separations. These same simulations are used
to demonstrate that the distribution of matches for a population of absorbers
randomly distributed in velocity space is peaked toward |Delta v| = 0, which
has implications for the statistical significance of matches. One of the triple
coincidences appears to be a strong absorber with a sheet-like, but
inhomogeneous, geometry and a coherence length approaching or exceeding 1 Mpc.

</DOC>
<DOC>
<DOCNO> 117693 </DOCNO>
Unsupervised Induction and Gamma-Ray Burst Classification


  We use ESX, a product of Information Acumen Corporation, to perform
unsupervised learning on a data set containing 797 gamma-ray bursts taken from
the BATSE 3B catalog. Assuming all attributes to be distributed logNormally,
Mukherjee et al. (1998) analyzed these same data using a statistical cluster
analysis. Utilizing the logarithmic values for T90 duration, total fluence, and
hardness ratio HR321 their results showed the instances formed three classes.
Class I contained long/bright/intermediate bursts, class II consisted of
short/faint/hard bursts and class III was represented by
intermediate/intermediate/soft bursts.
  When ESX was presented with these data and restricted to forming a small
number of classes, the two classes found by previous standard techniques were
determined. However, when ESX was allowed to form more than two classes, four
classes were created. One of the four classes contained a majority of short
bursts, a second class consisted of mostly intermediate bursts, and the final
two classes were subsets of the Class I (long) bursts determined by Mukherjee
et al. We hypothesize that systematic biases may be responsible for this
variation.

</DOC>
<DOC>
<DOCNO> 68044 </DOCNO>
Bottom quark electroproduction in variable flavor number schemes


  Two variable flavor number schemes are used to describe bottom quark
production in deep inelastic electron-proton scattering. In these schemes the
coefficient functions are derived from mass factorization of the heavy quark
coefficient functions presented in a fixed flavor number scheme. Also one has
to construct a parton density set with five light flavors (u,d,s,c,b) out of a
set which only contains four light flavors (u,d,s,c). In order $\alpha_s^2$ the
two sets are discontinuous at $\mu=m_b$ which follows from mass factorization
of the heavy quark coefficient functions when it is carried out in the ${\bar
{\rm MS}}$-scheme. Both variable flavor number schemes give almost identical
predictions for the bottom structure functions $F_{2,b}$ and $F_{L,b}$. Also
they both agree well with the corresponding results based on fixed order
four-flavor perturbation theory over a wide range in $x$ and $Q^2$.

</DOC>
<DOC>
<DOCNO> 101258 </DOCNO>
Ideals in transformation-group $C^*$-algebras


  We characterize the ideal of continuous-trace elements in a separable
transformation-group $C^{*}$-algebra $C_0(X)\times G$. In addition, we identify
the largest Fell ideal, the largest liminal ideal and the largest postliminal
ideal.

</DOC>
<DOC>
<DOCNO> 116548 </DOCNO>
Resonant radiative processes


  The frequency correlation properties of the radiation from an atom in a
strong field in resonance with neighboring transitions are considered. It is
shown that the difference in frequency correlation in two-photon and stepwise
processes decreases with increase of the external field. The spectral
compositions of the Doppler-broadened resonance scattering and fluorescence are
analyzed. It is shown that in these cases the Doppler line width is
anisotropic.

</DOC>
<DOC>
<DOCNO> 150881 </DOCNO>
AdS/CFT For Non-Boundary Manifolds


  In its Euclidean formulation, the AdS/CFT correspondence begins as a study of
Yang-Mills conformal field theories on the sphere, S^4. It has been
successfully extended, however, to S^1 X S^3 and to the torus T^4. It is
natural to hope that it can be made to work for any manifold on which it is
possible to define a stable Yang-Mills conformal field theory. We consider a
possible classification of such manifolds, and show how to deal with the most
obvious objection : the existence of manifolds which cannot be represented as
boundaries. We confirm Witten's suggestion that this can be done with the help
of a brane in the bulk.

</DOC>
<DOC>
<DOCNO> 122192 </DOCNO>
The Formation of Galaxy Disks


  Galaxy disk formation must incorporate the multiphase nature of the
interstellar medium. The resulting two-phase structure is generated and
maintained by gravitational instability and supernova energy input, which yield
a source of turbulent viscosity that is able to effectively compete in the
protodisk phase with early angular momentum loss of the baryonic component via
dynamical friction in the dark halo. Provided that star formation occurs on the
viscous drag time-scale, this mechanism provides a means of accounting for disk
sizes and radial profiles.
 The star formation feedback is self-regulated by turbulent gas
pressure-limited percolation of the supernova remnant-heated hot phase, but can
run away in gas-rich protodisks to generate compact starbursts. A simple
analytic model is derived for a Schmidt-like global star formation law in terms
of the cold gas volume density.

</DOC>
<DOC>
<DOCNO> 121374 </DOCNO>
CCD Photometry of the Globular Cluster NGC 4833 and Extinction Near the


  We present CCD photometry for the Galactic globular cluster NGC 4833. Our BVI
color magnitude diagrams (CMD) extend from above the red giant branch (RGB) tip
to several magnitudes below the main sequence turnoff. The principal sequences
of the cluster show the effects of differential reddening. We have created a
local extinction map, consistent with IRAS and COBE/DIRBE dust maps of the
region. We use our map to correct the colors and magnitudes of each star to the
value at the cluster center. The cluster horizontal branch (HB) is
predominately blueward of the instability strip with 13 confirmed RR Lyrae
variables and 5 additional RR Lyrae candidates. Using the 11 confirmed RR
Lyraes measured on our images, and the differential reddening corrected
photometry we calculate V(HB) = 15.56 +/- 0.063. We have used the simultaneous
reddening and metallicity method of Sarajedini (1994) to find the mean
reddening of the cluster E(B-V) = 0.32 +/- 0.03, and the mean metallicity
[Fe/H] = -1.83 +/- 0.14. As for the age of NGC 4833, we find provisional
evidence that NGC 4833 is 2 +/- 1 Gyr older than the average of M92 and M5. A
more definitive conclusion must await higher resolution imaging of the cluster
core where the effects of differential reddening are minimized.

</DOC>
<DOC>
<DOCNO> 122398 </DOCNO>
The X-ray evolution of clusters of galaxies to z=0.9


  The evolution of the X-ray luminosity function of clusters of galaxies has
been measured to z=0.9 using over 150 X-ray selected clusters discovered in the
WARPS survey. We find no evidence for evolution of the luminosity function at
any luminosity or redshift. The observations constrain the evolution of the
space density of moderate luminosity clusters to be very small, and much less
than predicted by most models of the growth of structure with Omega_m=1. All
the current X-ray surveys agree on this result. Several notable luminous
clusters at z>0.8 have been found, including one cluster which is more luminous
(and is probably more massive) than the well known MS1054 cluster.

</DOC>
<DOC>
<DOCNO> 11508 </DOCNO>
Decoherence in Nearly-Isolated Quantum Dots


  Decoherence in nearly-isolated GaAs quantum dots is investigated using the
change in average Coulomb blockade peak height upon breaking time-reversal
symmetry. The normalized change in average peak height approaches the predicted
universal value of 1/4 at temperatures well below the single-particle level
spacing, but is greatly suppressed for temperature greater than the level
spacing, suggesting that inelastic scattering or other dephasing mechanisms
dominate in this regime.

</DOC>
<DOC>
<DOCNO> 121780 </DOCNO>
On the paper by M. Valluri and D. Merritt "Orbital Instability and


  Some points related to the exponential instability of N-body gravitating
systems and which are misinterpreted in various papers are clarified.
Exponential instability is a phenomenon essentially responsible for the
relaxation, evolutionary, morphological and other properties of certain type of
galaxies and star clusters.

</DOC>
<DOC>
<DOCNO> 83348 </DOCNO>
Efficient probabilistic top-down and left-corner parsing


  This paper examines efficient predictive broad-coverage parsing without
dynamic programming. In contrast to bottom-up methods, depth-first top-down
parsing produces partial parses that are fully connected trees spanning the
entire left context, from which any kind of non-local dependency or partial
semantic interpretation can in principle be read. We contrast two predictive
parsing approaches, top-down and left-corner parsing, and find both to be
viable. In addition, we find that enhancement with non-local information not
only improves parser accuracy, but also substantially improves the search
efficiency.

</DOC>
<DOC>
<DOCNO> 170417 </DOCNO>
Addendum to ``Quantum key distribution without alternative


  Recently, Zhang, Li, and Guo have proposed a particular eavesdropping attack
[Phys. Rev. A {\bf 63}, 036301 (2001), quant-ph/0009042] which shows that my
quantum key distribution protocol based on entanglement swapping [Phys. Rev. A
{\bf 61}, 052312 (2000), quant-ph/9911025] is insecure. However, security
against this attack can be attained with a simple modification. In addition, a
simpler version of the protocol using four qubits is introduced.

</DOC>
<DOC>
<DOCNO> 71011 </DOCNO>
epsilon'/epsilon at next-to-leading in 1/N_c and to lowest order CHPT


  We report on a calculation of epsilon'/epsilon at next-to-leading in the
1/N_c expansion and to lowest order in Chiral Perturbation Theory. We also
discuss the chiral corrections to our results and give the result of including
the two known chiral corrections.

</DOC>
<DOC>
<DOCNO> 99904 </DOCNO>
Absolute Continuity of the Floquet Spectrum for a Nonlinearly Forced


  We prove that the Floquet spectrum of a class of time-periodic Schroedinger
equations under a a mildly nonlinear resonant forcing is purely absolutely
continuous.

</DOC>
<DOC>
<DOCNO> 178476 </DOCNO>
Radiative Corrections to Electron-Proton Scattering


  The radiative corrections to elastic electron-proton scattering are analyzed
in a hadronic model including the finite size of the nucleon. For initial
electron energies above 8 GeV and large scattering angles, the proton vertex
correction in this model increases by at least two percent the overall factor
by which the one-photon exchange (Rosenbluth) cross section must be multiplied.
The contribution of soft photon emission is calculated exactly. Comparison is
made with the generally used expressions previously obtained by Mo and Tsai.
Results are presented for some kinematics at high momentum transfer.

</DOC>
<DOC>
<DOCNO> 10226 </DOCNO>
Percolation line of stable clusters in supercritical fluids


  We predict that self-bound clusters of particles exist in the supercritical
phase of simple fluids. These clusters, whose internal temperature is lower
than the global temperature of the system, define a percolation line that
starts at the critical point. This line should be physically observable.
Possible experiments showing the validity of these predictions are discussed.

</DOC>
<DOC>
<DOCNO> 101323 </DOCNO>
Half twists of Hodge structures of CM-type


  To a Hodge structure V of weight k with CM by a field K we associate Hodge
structures V_{-n/2} of weight k+n for n positive and, under certain
circumstances, also for n negative. We show that these `half twists' come up
naturally in the Kuga-Satake varieties of weight two Hodge structures with CM
by an imaginary quadratic field.

</DOC>
<DOC>
<DOCNO> 119480 </DOCNO>
Cosmic strings in the age of Boomerang


  We show how two simple modifications to the standard cosmic string scenario
for structure formation compare to the recently released Boomerang data set.
Namely we consider pure string closed models and mixed models where both
inflation and strings are responsible for the perturbations. In the closed
models we find that pure string models would require a universe with roughly
$\Omega_M=0.8$, $\Omega_{\Lambda}=1.6$ to agree with the peak position revealed
by the data and in agreement with the SNIa data. In the hybrid scenario with
local strings we find that we require even more tilt and baryon content
($n_s\sim 0.8$, $\Omega_b=0.08$, $H_0=70$) to match the data than with pure
inflation models. The case with global strings fares better with a standard
period of $\Lambda$CDM inflation and a $\sim30%$ contribution from strings
being in good agreement with the data.

</DOC>
<DOC>
<DOCNO> 169811 </DOCNO>
Cavity implementation of quantum interference in a $\Lambda$-type atom


  A scheme for engineering quantum interference in a $\Lambda$-type atom
coupled to a frequency-tunable, single-mode cavity field with a pre-selected
polarization at finite temperature is proposed. Interference-assisted
population trapping, population inversions and probe gain at one sideband of
the Autler-Townes spectrum are predicted for certain cavity resonant
frequencies.

</DOC>
<DOC>
<DOCNO> 119292 </DOCNO>
Spectroscopy and Component Masses of the Eclipsing Dwarf Nova


  HS0907+1902 was recently discovered to be one of a handful of deeply
eclipsing dwarf novae with periods longward of the 2 -- 3 hr `gap'. This paper
presents orbit-resolved spectra and time series photometry of an eclipse. The
apparent velocity amplitude of the M-dwarf secondary is K_2 = 297 +- 15 km/s.
The phase of the radial velocities of the H-alpha emission line wings agrees
accurately (for once) with the phase of the white-dwarf motion deduced from the
eclipse, and an estimate of the emission-line velocity amplitude yields K1 =
115 +- 7 km/s. The eclipse width is delta-phi = 0.060 +- 0.005. At face value,
these measurements yield mass estimates of M1 = 0.99 +- 0.12 solar masses for
the white dwarf and M2 = 0.38 +- 0.06 solar masses for the secondary. The
eclipse width and nominal mass ratio constrain the binary inclination to be
77.3 +- 0.9 degree. The influence of systematic uncertainties on these values
is discussed; the conclusion that the white dwarf is somewhat more massive than
typical field white dwarfs appears to be robust.
  The H-alpha emission line profile out of eclipse is only slightly
double-peaked, but the line shows a strong rotational disturbance in eclipse.
Models of the line profile through eclipse using a flat, Keplerian disk do not
give a good quantitative match to the observations.

</DOC>
<DOC>
<DOCNO> 12215 </DOCNO>
Typical solution time for a vertex-covering algorithm on


  In this letter, we analytically describe the typical solution time needed by
a backtracking algorithm to solve the vertex-cover problem on
finite-connectivity random graphs. We find two different transitions: The first
one is algorithm-dependent and marks the dynamical transition from linear to
exponential solution times. The second one gives the maximum computational
complexity, and is found exactly at the threshold where the system undergoes an
algorithm-independent phase transition in its solvability. Analytical results
are corroborated by numerical simulations.

</DOC>
<DOC>
<DOCNO> 14168 </DOCNO>
Comment on Theory of Hall Effect and Electrical Transport in High-Tc


  I point out that a magnetotransport theory on the basis of the fluctuation
exchange (FLEX) approximation, which is proposed in order to explain anomalous
transport properties in the normal state of high-$T_{\rm c}$ cuprate
superconductors, is not compatible with the Fermi liquid theory and that the
anomaly obtained there ascribes to the inconsistency of the approximation.

</DOC>
<DOC>
<DOCNO> 101840 </DOCNO>
Curvature on determinant bundles and first Chern forms


  The Quillen-Bismut-Freed construction associates a determinant line bundle
with connection to an infinite dimensional super vector bundle with a family of
Dirac-type operators. We define the regularized first Chern form of the
infinite dimensional bundle, and relate it to the curvature of the Bismut-Freed
connection on the determinant bundle. In finite dimensions, these forms agree
(up to sign), but in infinite dimensions there is a correction term, which we
express in terms of Wodzicki residues. We illustrate these results with a
string theory computation. There is a natural super vector bundle over the
manifold of smooth almost complex structures on a Riemannian surface. The
Bismut-Freed superconnection is identified with classical Teichmuller theory
connections, and its curvature and regularized first Chern form are computed.

</DOC>
<DOC>
<DOCNO> 12599 </DOCNO>
Nonlinear equation for anomalous diffusion: unified power-law and


  The nonlinear diffusion equation $\frac{\partial \rho}{\partial t}=D
\tilde{\Delta} \rho^\nu$ is analyzed here, where $\tilde{\Delta}\equiv
\frac{1}{r^{d-1}}\frac{\partial}{\partial r} r^{d-1-\theta}
\frac{\partial}{\partial r}$, and $d$, $\theta$ and $\nu$ are real parameters.
This equation unifies the anomalous diffusion equation on fractals ($\nu =1$)
and the spherical anomalous diffusion for porous media ($\theta=0$). Exact
point-source solution is obtained, enabling us to describe a large class of
subdiffusion ($\theta > (1-\nu)d$), normal diffusion ($\theta= (1-\nu)d$) and
superdiffusion ($\theta < (1-\nu)d$). Furthermore, a thermostatistical basis
for this solution is given from the maximum entropic principle applied to the
Tsallis entropy.

</DOC>
<DOC>
<DOCNO> 14013 </DOCNO>
Collective Modes of Trapped Fermi Gases in the Normal Phase


  We consider the collective mode spectrum of a normal Fermi gas in a spherical
harmonic trap. Using a self-consistent random-phase-approximation, we
systematically examine the effects of the two-body interactions on the modes of
various symmetries. For weak coupling where the spectrum is shifted very little
away from the ideal gas case, a sum-rule approach is shown to work well.
 For stronger coupling, the interplay between the single particle and the
collective excitations causes effects such as mode splitting and Landau
damping. A finite low frequency response present at stronger coupling is
predicted for the quadrupole mode. Finally, we briefly discuss the effect of a
finite temperature on the spectrum and the excitation of higher collective
modes.

</DOC>
<DOC>
<DOCNO> 117005 </DOCNO>
New Method of Dispersion Correction in the Pep-II Low Energy Ring


  The sextupole magnets in the Low Energy Ring (LER) of PEP-II are grouped in
pairs with a phase advance of 180 degrees. Displacing the magnets or moving the
orbit to displace the beam in the magnets in an antisymmetric way creates a
dispersion wave around the ring. This can be used to correct the vertical
dispersion in LER without changing the local coupling. Results from simulations
are shown.

</DOC>
<DOC>
<DOCNO> 119658 </DOCNO>
Spectrum Analysis of the Type Ib Supernova 1999dn: Probable


  Low resolution spectra of SN 1999dn at early times are presented and compared
with synthetic spectra generated with the parameterized supernova
synthetic-spectrum code SYNOW. We find that the spectra of SN 1999dn strongly
resemble those of SN 1997X and SN 1984L, and hence we classify it as a Type Ib
event. Line-identifications are established through spectrum synthesis. Strong
evidence of both H-alpha and C II 6580 is found. We infer that H-alpha appears
first, before the time of maximum brightness, and then is blended with and
finally overwhelmed by the C II line after maximum; this favors a thin
high-velocity hydrogen skin in this Type Ib supernova.

</DOC>
<DOC>
<DOCNO> 170375 </DOCNO>
Comment on: "A quantum approach to static games of complete


  Recently Marinatto and Weber introduced an interesting new scheme for
quantizing games, and applied their scheme to the famous game 'Battle of the
Sexes'. In this Comment we make two observations: (a) the overall quantization
scheme is fundamentally very similar to a previous scheme proposed by Eisert et
al., and (b) in contrast to a main claim of the paper, the quantum Battle of
the Sexes game does not have a unique solution - a similar dilemma exists in
both the classical and the quantum versions.

</DOC>
<DOC>
<DOCNO> 8537 </DOCNO>
Resonances in Fock Space: Optimization of a SASER device


  We model the Fock space for the electronic resonant tunneling through a
double barrier including the coherent effects of the electron-phonon
interaction. The geometry is optimized to achieve the maximal optical phonon
emission required by a SASER (ultrasound emitter) device.

</DOC>
<DOC>
<DOCNO> 170024 </DOCNO>
Anisotropic Vacuum Induced Interference in Decay Channels


  We demonstrate how the anisotropy of the vacuum of the electromagnetic field
can lead to quantum interferences among the decay channels of close lying
states. Our key result is that interferences are given by the {\em scalar}
formed from the antinormally ordered electric field correlation tensor for the
anisotropic vacuum and the dipole matirx elements for the two transitions. We
present results for emission between two conducting plates as well as for a two
photon process involving fluorescence produced under coherent cw excitation

</DOC>
<DOC>
<DOCNO> 11549 </DOCNO>
Change, time and information geometry


  Dynamics, the study of change, is normally the subject of mechanics. Whether
the chosen mechanics is ``fundamental'' and deterministic or
``phenomenological'' and stochastic, all changes are described relative to an
external time. Here we show that once we define what we are talking about,
namely, the system, its states and a criterion to distinguish among them, there
is a single, unique, and natural dynamical law for irreversible processes that
is compatible with the principle of maximum entropy. In this alternative
dynamics changes are described relative to an internal, ``intrinsic'' time
which is a derived, statistical concept defined and measured by change itself.
Time is quantified change.

</DOC>
<DOC>
<DOCNO> 117268 </DOCNO>
The Mass Discrepancies Implied By Galactic Rotation Curves Are Not


  Galaxies as rotating systems involve a balance of gravitational attraction
and centripetal force. When the central mass is dominant the dynamics, referred
to as Keplerian, are that the orbital velocities are proportional to the
inverse square root of the path radius. A plot of velocity vs. path radius is a
Rotation Curve. For galaxies viewed as the disk edge we see one end moving
toward us relative to the center and the other moving away. The rotational
velocities are measured from the variation in redshift along the galactic
diameter. Rotation curves so obtained are not the expected Keplerian inverse
square root; rather, [beyond the galactic core] they are flat. In a solid
sphere all parts move at rotational velocities directly proportional to radius.
Since the observed flat curves lie between the Keplerian inverse square root of
radius and the solid's direct proportion to radius, a mass discrepancy is
inferred -- that unseen matter is dispersed throughout the galaxy, a halo of
"dark matter" that causes the curve form exhibited -- thus the "dark matter"
hypothesis. The mass discrepancy only appears where the acceleration is less
than 10-8 cm/sec2. Modeling gives an alternative hypothesis: Modification of
Newtonian Dynamics or MOND, that gravity and or inertia are modified when g or
a is less than 10-8 cm/sec2. No justification has been developed except
correlation with the mass discrepancies. An alternative explanation is
presented -- the general exponential decay of the overall universe, which has
been analyzed and developed in several papers. The universal decay accounts for
the mass discrepancies because the effect of the decay is to make the rotation
curves appear to deviate from the form expected in a Keplerian galactic disk
although the actual rotational behavior does not.

</DOC>
<DOC>
<DOCNO> 71973 </DOCNO>
The pairing Hamiltonian for one pair of nucleons bound in a potential


  The problem of one pair of identical nucleons sitting in ${\cal N}$ single
particle levels of a potential well and interacting through the pairing force
is treated introducing, in the Hamiltonian formalism, even Grassmann variables.
The eigenvectors are analytically expressed solely in terms of these with
coefficients fixed by the eigenvalues and the single particle energies. For
these a specific model is needed: in the case of the harmonic oscillator well,
for any strength of the pairing interaction, an accurate expression is derived
for both the collective eigenvalue and for those trapped in between the single
particle levels. Notably the latter are labelled through an index upon which
they depend parabolically.

</DOC>
<DOC>
<DOCNO> 13096 </DOCNO>
Non Metallic Transport in Molecular Solids versus Dimensionality


  Path integral techniques and Green functions formalism are applied to study
the (time) temperature dependent scattering of a polaronic quasiparticle by a
local anharmonic potential in a bath of diatomic molecules. The electrical
resistivity has been computed in any molecular lattice dimensionality for
different values of electron-phonon coupling and intermolecular forces. A broad
resistivity peak with non metallic behavior at temperatures larger than $\simeq
100K$ is predicted by the model for sufficiently strong polaron-local potential
coupling strengths. This peculiar behavior, ascribed to purely structural
effects, is favoured in low dimensionality.

</DOC>
<DOC>
<DOCNO> 10944 </DOCNO>
Statistical Mechanics of an Urban Cross: A solvable Model


  We propose a model for the intersection of two urban streets. The traffic
status of the crossroads is controlled by a set of traffic lights which
periodically switch to red and green with a total period of T. Two different
types of crossroads are discussed. The first one describes the intersection of
two one-way streets, while the second type models the intersection of a two-way
street with an one-way street. We assume that the vehicles approach the
crossroads with constant rates in time which are taken as the model parameters.
We optimize the traffic flow at the crossroads by minimizing the total waiting
time of the vehicles per cycle of the traffic light. This leads to the
determination of the optimum green-time allocated to each phase.

</DOC>
<DOC>
<DOCNO> 70439 </DOCNO>
Reducing the Theoretical Uncertainty in Extracting |V_{ub}| from the


  Utilizing asymptotic Pade-approximant methods, we estimate the three-loop
order MS-bar coefficients of alpha_s^3[\log(\mu^2/m^2_b(\mu)]^k terms [k =
{0,1,2,3}] within the $b \to u\ell^-\bar{\nu}_\ell$ decay rate. Except for the
coefficient of the k = 0 term, all other coefficients may also be obtained via
renormalization-group (RG) methods. The relative errors in asymptotic
Pade-approximant estimates of the k = {1,2,3} terms are found to be 5.1% or
less, thereby providing an estimate of the theoretical uncertainty in the
asymptotic Pade-approximant estimate of the RG-inaccessible k = 0 term. By a
judicious choice in the renormalization scale parameter, we are able to extract
|V_{ub}| from the inclusive decay rate to within 7% theoretical uncertainty.

</DOC>
<DOC>
<DOCNO> 151982 </DOCNO>
Quantization of maximally-charged slowly-moving black holes


  We discuss the quantization of a system of slowly-moving extreme
Reissner-Nordstrom black holes. In the near-horizon limit, this system has been
shown to possess an SL(2,R) conformal symmetry. However, the Hamiltonian
appears to have no well-defined ground state. This problem can be circumvented
by a redefinition of the Hamiltonian due to de Alfaro, Fubini and Furlan (DFF).
We apply the Faddeev-Popov quantization procedure to show that the Hamiltonian
with no ground state corresponds to a gauge in which there is an obstruction at
the singularities of moduli space requiring a modification of the quantization
rules. The redefinition of the Hamiltonian a la DFF corresponds to a different
choice of gauge. The latter is a good gauge leading to standard quantization
rules. Thus, the DFF trick is a consequence of a standard gauge-fixing
procedure in the case of black hole scattering.

</DOC>
<DOC>
<DOCNO> 9176 </DOCNO>
Statistical Mechanical Foundations for Systems with Nonexponential


  Traditionally the exponential canonical distributions of Gibbsian statistical
mechanics are given theoretical justification in at least four different ways:
steepest descent method, counting method, Khinchin's method based on te central
limit theorem, and maximum entropy principle of Jaynes. Equally ubiquitous
power-law canonical distributions are shown to be given similar justification
by appropriately adopting these formulations.

</DOC>
<DOC>
<DOCNO> 100011 </DOCNO>
Definitive Computation of Bernstein-Sato Polynomials


  Let n and d be positive integers, let k be a field and let P(n,d;k) be the
space of the polynomials in n variables of degree at most d with coefficients
in k. Let B(n,d) be the set of the Bernstein-Sato polynomials of all
polynomials in P(n,d;k) as k varies over all fields of characteristic 0. G.
Lyubeznik proved that B(n,d) is a finite set and asked if, for a fixed k, the
set of the polynomials corresponding to each element of B(n,d) is a
constructible subset of P(n,d;k).
  In this paper we give an affirmative answer to Lyubeznik's question by
showing that the set in question is indeed constructible and defined over Q,
i.e. its defining equations are the same for all fields k. Moreover, we
construct an algorithm that for each pair (n,d) produces a complete list of the
elements of B(n,d) and, for each element of this list, an explicit description
of the constructible set of polynomials having this particular Bernstein-Sato
polynomial.

</DOC>
<DOC>
<DOCNO> 70491 </DOCNO>
Origin of neutrino masses and mixings


  A brief overview of the important theoretical issues in neutrino physics is
presented and some of the current ideas for addressing them in the framework of
the seesaw mechanism of neutrino masses are discussed. Among the topics
discussed are ways to understand maximal mixing pattern among the three
neutrino species, both uni-maximal and bimaximal kinds. Constraints from
baryogenesis on mixing patterns are noted. In the last section, the question of
understanding the small masses for sterile neutrinos, which seem to be needed
for various reasons is addressed.

</DOC>
<DOC>
<DOCNO> 70633 </DOCNO>
Reconstruction of Supersymmetric Theories at High Energy Scales


  We have studied the reconstruction of supersymmetric theories at high scales
by evolving the fundamental parameters from the electroweak scale upwards.
Universal minimal supergravity and gauge mediated supersymmetry breaking have
been taken as representative alternatives. Pseudo-fixed point structures
require the low-energy boundary values to be measured with high precision.

</DOC>
<DOC>
<DOCNO> 151622 </DOCNO>
Finite Temperature Effects in the Supergravity Dual of the N=1* Gauge


  We consider the supergravity dual of the N=1* theory at finite temperature by
applying the Polchinski-Strassler construction to the black D3 brane solution
of Type IIB supergravity. At finite temperature the 5-brane probe action is
minimized when the probe falls to the horizon, although metastable minima with
r>>r_H persist for a range of temperatures. Thermal effects on the 3-form
source for the hypermultiplet mass m and its order m^2 back reaction on the
other fields of the IIB theory are computed. We find unique solutions which are
regular at the horizon and have the correct behavior on the boundary. For fixed
temperature T, the horizon shrinks for increasing m^2 suggesting that there is
a critical temperature separating the system into high and low temperature
phases. In the high temperature phase 5-branes are unnecessary since there are
no naked singularities. Using the order m^2 correction to the horizon area we
calculate the correction to the entropy to be \Delta S =-0.1714N^2m^2T, which
is less than the free field result.

</DOC>
<DOC>
<DOCNO> 72207 </DOCNO>
QCD Pomeron at Linear Colliders


  Recent developments in theory on the calculation of \gamma^* \gamma^*
reaction at high energies, in the aim of detecting the BFKL Pomeron signals,
are briefly introduced. The importance of the NLO QCD corrections to the Photon
Impact Factor in the game is highlighted.

</DOC>
<DOC>
<DOCNO> 122645 </DOCNO>
The Development of Gas/Star Offsets in Tidal Tails


  We present models of interacting galaxies in order to study the development
of spatial offsets between the gaseous and stellar components in tidal tails.
Observationally, such offsets are observed to exist over large scales (e.g.,
NGC 3690; Hibbard et al. 2000), suggesting an interaction between the tidal gas
and some (unseen) hot ISM. Instead, our models show these offsets are a natural
consequence of the radially extended HI spatial distribution in disk galaxies,
coupled with internal dissipation in the gaseous component driven by the
interaction. This mechanism is most effective in systems involved in very
prograde interactions, and explains the observed gas/star offsets in
interacting galaxies without invoking interactions with a hot ISM, starburst
ionization, or dust obscuration within the tails.

</DOC>
<DOC>
<DOCNO> 69202 </DOCNO>
Neutrinos: How Do They Mix and Violate CP ?


  We discuss a simple model of lepton mixing and CP violation based on the
flavor democracy of charge leptons and the mass degeneracy of neutrinos. A
nearly bi-maximal flavor mixing pattern, which is favored by current data on
atmospheric and solar neutrino oscillations, emerges naturally from this model
after explicit symmetry breaking. The rephasing-invariant strength of CP or T
violation can be as large as one percent, leading to significant probability
asymmetries between \nu_\mu \to \nu_e and \bar{\nu}_\mu \to \bar{\nu}_e (or
\nu_e \to \nu_\mu) transitions in the long-baseline neutrino experiments. The
possible matter effects on CP- and T-violating asymmetries are also taken into
account.

</DOC>
<DOC>
<DOCNO> 100065 </DOCNO>
Energy levels of steady states for thin film type equations


  We study the phase space of the evolution equation h_t = -(f(h) h_{xxx})_x -
(g(h) h_x)_x by means of a dissipated energy (a Liapunov function). Here h(x,t)
is nonnegative, and at h=0 the coefficient functions f>0 and g can either
degenerate to 0, or blow up to infinity, or tend to a nonzero constant.
  We first show all positive periodic steady states are 'energy unstable' fixed
points for the evolution (meaning the energy decreases under some zero--mean
perturbation) if g/f is convex or if the perturbations are allowed to have
period longer than that of the steady state.
  For power law coefficients (f(y) = y^n and g(y) = B y^m for some B > 0) we
analytically determine the relative energy levels of distinct steady states.
For example, with m-n in [1,2) and for suitable choices of the period and mean
value, we find three fundamentally different steady states. The first is a
constant steady state that is nonlinearly stable and is a local minimum of the
energy. The second is a positive periodic steady state that is linearly
unstable and has higher energy than the constant steady state; it is a saddle
point. The third is a periodic collection of 'droplet' (compactly supported)
steady states having lower energy than either the positive steady state or the
constant one. Since the energy must decrease along every orbit, these results
significantly constrain the dynamics of the evolution equation.
  Our results suggest that heteroclinic connections could exist between certain
of the steady states, for example from the periodic steady state to the droplet
one. In a companion article we perform numerical simulations to confirm their
existence.

</DOC>
<DOC>
<DOCNO> 69231 </DOCNO>
The sl(2) affine Toda model coupled to the matter: solitons and


  The so-called conformal affine Toda theory coupled to the matter fields
(CATM), associated to the $\hat{sl}(2)$ affine Lie algebra, is studied. The
conformal symmetry is fixed by setting a connection to zero, then one defines
an off-critical model, the affine Toda model coupled to the matter (ATM). The
quantum version of this reduction process is discussed by means of the
perturbative Lagrangian viewpoint, showing that the ATM theory is a
spontaneously broken and reduced version of the CATM model. We show, using
bosonization techniques that the off-critical theory decouples into a
sine-Gordon model and a free scalar. Using the "dressing" transformation method
we construct the explicit forms of the one and two-soliton classical solutions,
and show that a physical bound soliton-antisoliton pair (breather) does not
exist. Moreover, we verify that these solutions share some features of the
sine- Gordon (massive Thirring) solitons, and satisfy the classical equivalence
of topological and Noether currents in the ATM model. Imposing the Noether and
topological currents equivalence as a constraint, one can show that the ATM
model leads to a bag model like mechanism for the confinement of the U(1)
"color" charge inside the sine-Gordon solitons (baryons).

</DOC>
<DOC>
<DOCNO> 70831 </DOCNO>
Rapidly rotating strange stars for a new equation of state of strange


  For a new equation of state of strange quark matter, we construct equilibrium
sequences of rapidly rotating strange stars in general relativity. The
sequences are the normal and supramassive evolutionary sequences of constant
rest mass. We also calculate equilibrium sequences for a constant value of
$\Omega$ corresponding to the most rapidly rotating pulsar PSR 1937 + 21. In
addition to this, we calculate the radius of the marginally stable orbit and
its dependence on $\Omega$, relevant for modeling of kilo-Hertz quasi-periodic
oscillations in X-ray binaries.

</DOC>
<DOC>
<DOCNO> 71960 </DOCNO>
Neutrino Magnetic Moment Solution for the Solar Neutrino Problem and the


  The motivations for the magnetic moment solution to the solar neutrino
problem are briefly reviewed and the expected values for a number of
observables to be measured by the SNO experiment are calculated assuming three
different solar magnetic field profiles. The observables examined are the
charged current event rate, the ratio of the neutral current to the charged
current event rates and the charged current electron spectrum as well as their
first and second moments. The dependence of results on the hep neutrino flux is
also analysed and a comparison is made with the corresponding oscillation
results.

</DOC>
<DOC>
<DOCNO> 117547 </DOCNO>
7Li in Metal-Poor Stars: The Spread of the Li Plateau


  A highly homogeneous study of 23 halo field dwarf stars has achieved a Li
abundance accuracy of 0.033 dex per star. The work shows that the intrinsic
spread of the Li abundances of these stars at a given metallicity is <0.02 dex,
and consistent with zero. That is, the Spite Li plateau for halo field dwarfs
is incredibly thin. The thinness rules out depletion by more than 0.1 dex by a
rotational-induced extra-mixing mechanism. Despite the thinness of the plateau,
an increase of Li with [Fe/H] is seen, interpreted as evidence of Galactic
chemical evolution (GCE) of Li, primarily due to Galactic cosmic ray (GCR)
spallation reactions in the era of halo formation. The rate of Li evolution is
concordant with: (1) observations of spallative 6Li in halo dwarfs; (2) GCE
models; and (3) data on Li in higher metallicity halo stars. New data have also
revealed four new ultra-Li-deficient halo dwarfs, doubling the number known.
Based on their propensity to cluster at the halo main sequence turnoff and also
to exist redward of the turnoff, we hypothesise that they are the products of
binary mergers that ultimately will become blue stragglers. We explain their
low Li abundances by normal pre-main-sequence (and possibly main-sequence)
destruction in the low mass stars prior to their merging. If this explanation
is correct, then such stars need no longer be considered an embarrassment to
the existence of negligible Li destruction in the majority of field halo
dwarfs.

</DOC>
<DOC>
<DOCNO> 99869 </DOCNO>
Harmonic Splittings of Surfaces


  We give a proof, using harmonic maps from disks to real trees, of Skora's
theorem (Morgan-Otal (1993), Skora (1990), originally conjectured by Shalen):
if G is the fundamental group of a surface of genus at least 2, then any small
minimal G-action on a real tree is dual to the lift of a measured foliation.
  Analytic tools like the maximum principle are used to simplify the usual
combinatorial topology arguments. Other analytic objects associated to a
harmonic map, such as the Hopf differential and the moduli space of harmonic
maps, are also introduced as tools for understanding the action of surface
groups on trees.

</DOC>
<DOC>
<DOCNO> 11596 </DOCNO>
Models of core reconstruction for the 90-degree partial dislocation in


  We compare the models that have been proposed in the literature for the
atomic structure of the 90-degree partial dislocation in the homopolar
semiconductors, silicon, diamond, and germanium. In particular, we examine the
traditional single-period and our recently proposed double-period core
structures. Ab-initio and tight-binding results on the core energies are
discussed, and the geometries are compared in light of the available
experimental information about dislocations in these systems. The double-period
geometry is found to be the ground-state structure in all three materials. We
address boundary-conditions issues that have been recently raised about these
results. The structures of point excitations (kinks, solitons, and kink-soliton
complexes) in the two geometries are also reviewed.

</DOC>
<DOC>
<DOCNO> 40453 </DOCNO>
O'Mega: An Optimizing Matrix Element Generator


  I sketch the architecture of O'Mega, a new optimizing compiler for tree
amplitudes in quantum field theory. O'Mega generates the most efficient code
currently available for scattering amplitudes for many polarized particles in
the standard model. A complete infrastructure for physics beyond the standard
model is provided.

</DOC>
<DOC>
<DOCNO> 120688 </DOCNO>
A physical model for the hard X-ray background


  We combine a semi-analytic galaxy formation model (Nulsen and Fabian 1997)
with a prescription for the obscured growth of massive black holes (Nulsen and
Fabian 2000; Fabian 1999), to reproduce the hard X-ray background (XRB), the
local 2-10keV AGN luminosity function and the source counts, including recent
Chandra results. The model also complies with constraints on the AGN
contribution to the far-infrared and sub-mm backgrounds.
  The co-moving density of luminous AGN [L(2-10keV)>1E44 erg/s, in the
unabsorbed rest- frame] in the model declines sharply since z=2, mimicking the
observed evolution of the quasar population. The abundance of lower luminosity
AGN simultaneously increases, and we identify such objects with the Seyfert
galaxies. These features reflect an epoch-dependent rate of Bondi accretion
from the hot, cooling atmosphere: at z<2.5 most AGN are fed at much less than
10 per cent of the Eddington rate, whilst at z>2.5 most accrete at 10-50 per
cent Eddington. Unlike other models for quasar and galaxy formation, we do not
consider major mergers between normal galaxies.
  The model produces an excess soft XRB below 4keV which can be removed by
modifying the wind expulsion model of Fabian (1999) to incorporate anisotropic
ejection.

</DOC>
<DOC>
<DOCNO> 70931 </DOCNO>
Two loop mass effects in the static position space QCD-potential


  The perturbatively calculable short distance QCD potential is known to two
loops including the effect of massive quarks. Recently, a simple approximate
solution in momentum space was utilized to obtain the potential in coordinate
space. The latter is important in several respects. A comparison with
non-perturbative lattice results is feasible in the overlap regime using light
$\bar{MS}$ masses. This might be even more promising employing the concept of
the force between the heavy color singlet sources, which can be easily derived
from the potential. In addition, the better than two percent accuracy bottom
mass determination from $\Upsilon$-mesons is sensitive to massive charm loops
at the two loop order. We summarize recent results using exact one loop
functions and explicit decoupling parametrizations.

</DOC>
<DOC>
<DOCNO> 9075 </DOCNO>
Magnetic Behavior of a Mixed Ising Ferrimagnetic Model in an Oscillating


  The magnetic behavior of a mixed Ising ferrimagnetic system on a square
lattice, in which the two interpenetrating square sublattices have spins +- 1/2
and spins +-1,0, in the presence of an oscillating magnetic field has been
studied with Monte Carlo techniques. The model includes nearest and
next-nearest neighbor interactions, a crystal field and the oscillating
external field. By studying the hysteretic response of this model to an
oscillating field we found that it qualitatively reproduces the increasing of
the coercive field at the compensation temperature observed in real
ferrimagnets, a crucial feature for magneto-optical applications. This behavior
is basically independent of the frequency of the field and the size of the
system. The magnetic response of the system is related to a dynamical
transition from a paramagnetic to a ferromagnetic phase and to the different
temperature dependence of the relaxation times of both sublattices.

</DOC>
<DOC>
<DOCNO> 117312 </DOCNO>
Do we need to recourse to Ampere-Neumann electrodynamics to explain wire


  Exploding wires are widely used in many experimental setups and pulsed power
systems. However, many aspects of the process of wire fragmentation still
remain unclear. If the current density is not too high, the wire may break up
in the solid state.
  In a series of papers, see references therein, Graneau argued that neither
mechanical vibrations induced by the electromagnetic pinch force nor thermal
expansion could have been responsible for the wire disintegration because they
were too weak. To explain the phenomenon he appealed to the obsolete Ampere
force law as opposed to the conventional Biot-Savart force law. Graneau argued
that the Ampere force law would lead to a longitudinal tension in the wire,
although his calculations may have been in error on this point. Therefore,
Graneau's explanations induced a controversy in electrodynamics with a number
of authors arguing pro and con.
  In this investigation, we use a simplified magneto-thermo-elastic model to
study flexural vibrations induced by high pulsed currents in wires with clumped
ends on account of their role in the disintegration process. It is shown that
the induced flexural vibrations are strong enough to lead to the breaking of
the wire in a wide range of parameters.

</DOC>
<DOC>
<DOCNO> 84816 </DOCNO>
Brans-Dicke corrections to the gravitational Sagnac effect


  The {\it exact} formulation for the effect of the Brans-Dicke scalar field on
the gravitational corrections to the Sagnac delay in the Jordan and Einstein
frames is presented for the first time. The results completely agree with the
known PPN factors in the weak field region. The calculations also reveal how
the Brans-Dicke coupling parameter (appears in various correction terms for
different types of source/observer orbits. A first order correction of roughly
2.83 x 10^{-1} fringe shift for visible light is introduced by the
gravity-scalar field combination for Earth bound equatorial orbits. It is also
demonstrated that the final predictions in the two frames do not differ. The
effect of the scalar field on the geodetic and Lense-Thirring precession of a
spherical gyroscope in circular polar orbit around the Earth is also computed
with an eye towards the Stanford Gravity Probe-B experiment currently in
progress. The feasibility of optical and matter-wave interferometric
measurements is discussed briefly.

</DOC>
<DOC>
<DOCNO> 68479 </DOCNO>
The Role of $B_s \to K \pi$ in Determining the Weak Phase $\gamma$


  The decay rates for $B^0 \to K^+ \pi^-$, $B^+ \to K^0 \pi^+$, and the
charge-conjugate processes were found to provide information on the weak phase
$\gamma \equiv {\rm Arg}(V_{ub}^*)$ when the ratio $r$ of weak tree and penguin
amplitudes was taken from data on $B \to \pi \pi$ or semileptonic $B \to \pi$
decays. We show here that the rates for $B_s \to K^- \pi^+$ and $\bar B_s \to
K^+ \pi^-$ can provide the necessary information on $r$, and estimate the
statistical accuracy of forthcoming measurements at the Fermilab Tevatron.

</DOC>
<DOC>
<DOCNO> 101029 </DOCNO>
On the motive of the Hilbert scheme of points on a surface


  We determine the class of the Hilbert scheme of points on a surface in the
Grothendieck group of varieties. As a corollary we obtain its class in the
Grothendieck group of motives. We give some applications to moduli spaces of
sheaves on surfaces. The paper is related to math/0005249 of de Cataldo and
Migliorini.

</DOC>
<DOC>
<DOCNO> 40145 </DOCNO>
Limit on Lorentz and CPT Violation of the Proton Using a Hydrogen Maser


  We present a new measurement constraining Lorentz and CPT violation of the
proton using a hydrogen maser double resonance technique. A search for hydrogen
Zeeman frequency variations with a period of the sidereal day (23.93 h) sets a
clean limit on violation of Lorentz and CPT symmetry of the proton at the
10^{-27} GeV level.

</DOC>
<DOC>
<DOCNO> 151405 </DOCNO>
Deformed Heisenberg Algebra with Reflection, Anyons and Supersymmetry of


  Deformed Heisenberg algebra with reflection appeared in the context of
Wigner's generalized quantization schemes underlying the concept of parafields
and parastatistics of Green, Volkov, Greenberg and Messiah. We review the
application of this algebra for the universal description of ordinary spin-$j$
and anyon fields in 2+1 dimensions, and discuss the intimate relation between
parastatistics and supersymmetry.

</DOC>
<DOC>
<DOCNO> 13735 </DOCNO>
Superconductivity in Disordered Sr2RuO4


  We discuss the influence of disorder on the critical temperature Tc of a
p-wave superconductor. To describe disordered Sr2RuO4 we use the extended
Hubbard model with random site energies treated in the Coherent Potential
Approximation.

</DOC>
<DOC>
<DOCNO> 178521 </DOCNO>
The structure of the nucleon


  These lectures give an introduction to the structure of the nucleon as seen
with the electromagnetic probe. Particular emphasis is put on the form factors,
the strangeness content, Compton scattering and polarizabilities, pion photo-
and electroproduction, the spin structure and sum rules. The existing data are
compared to predictions obtained from chiral perturbation theory, dispersion
theory and effective Lagrangians.

</DOC>
<DOC>
<DOCNO> 119537 </DOCNO>
The Magnetic Field Sign Reversal and Evolution of Rossby and Alfven


  The behaviour of the toroidal and meridional components of the solar
large-scale magnetic field and linear Alfven and Rossby waves during solar
activity cycles and bi-annual time periods are theoretically investigated in
this work. We consider the case of periodical velocity shear with bi-annual
oscillation period . The large-scale magnetic field toroidal and meridional
components are obtained as harmonic functions of the time. The sign reversal of
these magnetic field components is studied. The numerical simulations show
that, due to the velocity shear oscillations, the toroidal or meridional
component of the large-scale magnetic field reverses its sign three times in
one of the hemispheres (northern or southern) of the Sun, during the solar
activity cycle 23. According to our results the appearance of velocity shear
oscillations leads to the modulation of the magnetic field 22-year period
oscillations by the bi-annual ones. The presented model is applicable for
investigation of the magnetic field evolution at the base of convection zone as
well as for understanding the magnetic field properties in the upper solar
atmosphere. The excitement of the linear Rossby and Alfven waves in the shear
layer at the base of the convection zone is also considered. The periodical
impulsive growth is characteristic to the energy density of Alfven and Rossby
waves and they propagate as localized in time powerful pulses. Such behavior of
waves well explains mechanisms of the solar flare excitement and activity.

</DOC>
<DOC>
<DOCNO> 84488 </DOCNO>
Entropy generation and inflation in wave collision induced pre-big-bang


  We study inflation and entropy generation in a recently proposed pre-big-bang
model universe produced in a collision of gravitational and dilaton waves. It
is shown that enough inflation occurs provided the incoming waves are
sufficiently weak. We also find that entropy in this model is dynamically
generated as the result of the nonlinear interaction of the incoming waves,
before the universe enters the phase of dilaton driven inflation. In
particular, we give the scaling of the entropy produced in the collision in
terms of the focusing lengths of the incoming waves.

</DOC>
<DOC>
<DOCNO> 100117 </DOCNO>
The von Neumann algebra of the non-residually finite Baumslag group <


  In this paper we analyze the structure of some sets of non-commutative
moments of elements in a finite von Neumann algebra M. If the fundamental group
of M is R_+\{0}, then the moment sets are convex, and if M is isomorphic to M
tensor M, then the sets are closed under pointwise multiplication. We introduce
a class of discrete groups that we call hyperlinear. These are the discrete
subgroups (with infinite conjugacy classes) of the unitary group of R^omega. We
prove that this class is strictly larger than the class of (i.c.c.) residually
finite groups. In particular, it contains the Baumslag group < a,b | a b^3 a^-1
= b^2 >. This leads to a previously unknown (non-hyperfinite) type II_1 factor
that can be embedded in R^omega. This is positive evidence for Connes's
conjecture that any separable II_1 factor can be embedded into R^omega.

</DOC>
<DOC>
<DOCNO> 7829 </DOCNO>
Quantum Hall Solitons with Intertwined Spin and Pseudospin at $\nu = \


  In this paper we study in detail different types of topological solitons
which are possible in bilayer quantum Hall systems at filling fraction $\nu =1$
when spin degrees of freedom are included. Starting from a microscopic
Hamiltonian we derive an effective energy functional for studying such
excitations. The gauge invariance and $CP^{3}$ character of this energy
fuctional and their consequences are examined. Then we identify permissible
classes of finite energy solutions which are topologically non-trivial. We also
numerically evaulate a representative solution in which a pseudospin (layer
degrees of freedom) bimeron in a given spin component is intertwined with
spin-skyrmions in each layer, and and discuss whether it is energetically
favoured as the lowest lying excitation in such system with some numerical
results.

</DOC>
<DOC>
<DOCNO> 10364 </DOCNO>
Aging of the Zero-Field-Cooled Magnetization in Ising Spin Glasses:


  A new protocol of the zero-field-cooled (ZFC) magnetization process is
studied experimentally on an Ising spin-glass (SG)
Fe$_{0.50}$Mn$_{0.50}$TiO$_3$ and numerically on the Edwards-Anderson Ising SG
model. Although the time scales differ very much between the experiment and the
simulation, the behavior of the ZFC magnetization observed in the two systems
can be interpreted by means of a common scaling expression based on the droplet
picture. The results strongly suggest that the SG coherence length, or the mean
size of droplet excitations, involved even in the experimental ZFC process, is
about a hundred lattice distances or less.

</DOC>
<DOC>
<DOCNO> 8856 </DOCNO>
Chern-Simons Theory for Quantum Hall Stripes


  We develop a Chern-Simons theory to describe a two-dimensional electron gas
in intermediate magnetic fields. Within this approach, inhomogeneous states
emerge in analogy to the intermediate state of a superconductor. At half
filling of the highest Landau level we find unidirectional charge-density-wave
(CDW) solutions. With a semiclassical calculation we give an intuitive
explanation of the change of CDW orientation in the presence of an in-plane
magnetic field. An anisotropy in the electron band mass is suggested as a
possible source of the reproducible orientation of the CDW.

</DOC>
<DOC>
<DOCNO> 117676 </DOCNO>
New Techniques for Relating Dynamically Close Galaxy Pairs to Merger and


  We introduce two new pair statistics, which relate close galaxy pairs to the
merger and accretion rates. We demonstrate the importance of correcting these
(and other) pair statistics for selection effects related to sample depth and
completeness. In particular, we highlight the severe bias that can result from
the use of a flux-limited survey. The first statistic, denoted N_c, gives the
number of companions per galaxy, within a specified range in absolute
magnitude. N_c is directly related to the galaxy merger rate. The second
statistic, called L_c, gives the total luminosity in companions, per galaxy.
This quantity can be used to investigate the mass accretion rate. Both N_c and
L_c are related to the galaxy correlation function and luminosity function in a
straightforward manner. We outline techniques which account for various
selection effects, and demonstrate the success of this approach using Monte
Carlo simulations. If one assumes that clustering is independent of luminosity
(which is appropriate for reasonable ranges in luminosity), then these
statistics may be applied to flux-limited surveys.
  These techniques are applied to a sample of 5426 galaxies in the SSRS2
redshift survey. Using close dynamical pairs, we find N_c(-21<M_B<-18) =
0.0226+/-0.0052 and L_c(-21<M_B<-18) = 0.0216+/-0.0055 10^{10} h^2 L_sun at
z=0.015. These are the first secure estimates of low-z close pair statistics.
If N_c remains fixed with redshift, simple assumptions imply that ~ 6.6% of
present day galaxies with -21<M_B<-18 have undergone mergers since z=1. When
applied to redshift surveys of more distant galaxies, these techniques will
yield the first robust estimates of evolution in the galaxy merger and
accretion rates. [Abridged]

</DOC>
<DOC>
<DOCNO> 14032 </DOCNO>
A Density Matrix Renormalization Group study of Excitons in Dendrimers


  We introduce the density matrix renormalization group (DMRG) method as an
efficient computational tool for one-exciton approximations with off-diagonal
disorder. This method allows us to reduce the computational effort by
targetting only a few low-lying eigenstates at each statistical sampling, in
contrast to the exact diagonalization methods that compute the whole spectrum.
As an application of the method, we study excitons in two families of branched
molecules called dendrimers using a recently introduced simple model. We
compute the absortion peaks for these dendrimers varying their generation
number $g$ and number of wedges $w$.

</DOC>
<DOC>
<DOCNO> 102868 </DOCNO>
Walks on the slit plane


  In the first part of this paper, we enumerate exactly walks on the square
lattice that start from the origin, but otherwise avoid the non positive
horizontal half-axis. We call them "walks on the slit plane". We count them by
their length, and by the coordinates of their endpoint. The corresponding three
variable generating function is algebraic of degree 8. Moreover, for any point
(i,j), the length generating function for walks of this type ending at (i,j) is
also algebraic, of degree 2 or 4, and involves the famous Catalan numbers. Our
method is based on the solution of a functional equation, established via a
simple combinatorial argument. It actually works for more general models, in
which walks take their steps in a finite subset of Z^2 satisfying two simple
conditions. The corresponding generating functions are always algebraic. In the
second part of the paper, we derive from our enumerative results a number of
probabilistic corollaries. For instance, we can compute exactly the probability
that an ordinary random walk starting from (i,j) hits for the first time the
horizontal half-axis at position (k,0), for any triple (i,j,k). This
generalizes a question raised by R. Kenyon, which was the starting point of
this paper. Taking uniformly at random all n-step walks on the slit plane, we
also compute the probability that they visit a given point (k,0), and the
average number of visits to this point. In other words, we quantify the
transience of the walks. Finally, we derive an explicit limit law for the
coordinates of their endpoint.

</DOC>
<DOC>
<DOCNO> 9119 </DOCNO>
I. Territory covered by N random walkers on deterministic fractals. The


  We address the problem of evaluating the number $S_N(t)$ of distinct sites
visited up to time t by N noninteracting random walkers all initially placed on
one site of a deterministic fractal lattice. For a wide class of fractals, of
which the Sierpinski gasket is a typical example, we propose that, after the
short-time compact regime and for large N, $S_N(t) \approx \hat{S}_N(t)
(1-\Delta)$, where $\hat{S}_N(t)$ is the number of sites inside a hypersphere
of radius $R [\ln (N)/c]^{1/ u}$, R is the root-mean-square displacement of a
single random walker, and u and c determine how fast $1-\Gamma_t({\bf r})$ (the
probability that site ${\bf r}$ has been visited by a single random walker by
time t) decays for large values of r/R: $1-\Gamma_t({\bf r})\sim
\exp[-c(r/R)^u]$. For the deterministic fractals considered in this paper, $ u
=d_w/(d_w-1)$, $d_w$ being the random walk dimension. The corrective term
$\Delta$ is expressed as a series in $\ln^{-n}(N) \ln^m \ln (N)$ (with $n\geq
1$ and $0\leq m\leq n$), which is given explicitly up to n=2. Numerical
simulations on the Sierpinski gasket show reasonable agreement with the
analytical expressions. The corrective term $\Delta$ contributes substantially
to the final value of $S_N(t)$ even for relatively large values of N.

</DOC>
<DOC>
<DOCNO> 69913 </DOCNO>
Cosmological magnetic fields by parametric resonance?


  We investigate the possibility that electromagnetic fluctuations are
amplified in expanding universe by parametric resonance, during the oscillatory
regime of a scalar field to which they are coupled. We consider scalar
electrodynamics and we find that electromagnetic fluctuations undergo
exponential instabilities. This mechanism could have some relevance for the
problem of large scale primordial magnetic fields.

</DOC>
<DOC>
<DOCNO> 10221 </DOCNO>
Effects of ac-field amplitude on the dielectric susceptibility of


  The thermally activated flips of the local spontaneous polarization in
relaxors were simulated to investigate the effects of the applied-ac-field
amplitude on the dielectric susceptibility. It was observed that the
susceptibility increases with increasing the amplitude at low temperatures. At
high temperatures, the susceptibility experiences a plateau and then drops. The
maximum in the temperature dependence of susceptibility shifts to lower
temperatures when the amplitude increases. A similarity was found between the
effects of the amplitude and frequency on the susceptibility.

</DOC>
<DOC>
<DOCNO> 8344 </DOCNO>
The effect of the annealing temperature on the local distortion of


  Mn $K$-edge fluorescence data are presented for thin film samples (3000~\AA)
of Colossal Magnetoresistive (CMR) La$_{0.67}$Ca$_{0.33}$MnO$_3$: as-deposited,
and post-annealed at 1000 K and 1200 K. The local distortion is analyzed in
terms of three contributions: static, phonon, and an extra,
temperature-dependent, polaron term. The polaron distortion is very small for
the as-deposited sample and increases with the annealing temperature. In
contrast, the static distortion in the samples decreases with the annealing
temperature. Although the local structure of the as-deposited sample shows very
little temperature dependence, the change in resistivity with temperature is
the largest of these three thin film samples. The as-deposited sample also has
the highest magnetoresistance (MR), which indicates some other mechanism may
also contribute to the transport properties of CMR samples. We also discuss the
relationship between local distortion and the magnetization of the sample.

</DOC>
<DOC>
<DOCNO> 151745 </DOCNO>
A Note on Gauge Invariant Operators in Noncommutative Gauge Theories and


  In this note we discuss local gauge-invariant operators in noncommutative
gauge theories. Inspired by the connection of these theories with the Matrix
model, we give a simple construction of a complete set of gauge-invariant
operators. We make connection with the recent discussions of candidate
operators which are dual to closed strings modes. We also discuss large Wilson
loops which in the limit of vanishing noncommutativity, reduce to the closed
Wilson loops of the ordinary gauge theory.

</DOC>
<DOC>
<DOCNO> 101694 </DOCNO>
The Center Variety of Polynomial Differential Systems


  We investigate the symmetry component of the center variety of polynomial
differential systems, corresponding to systems with an axis of symmetry in the
real plane. We give a general algorithm to find this irreducible subvariety and
compute its dimension. We show that our methods provide a simple way to compute
the radical of the ideal generated by the focus quantities and, therefore, to
estimate the cyclicity of a center in the case when the ideal is radical. In
particular, we use our methods to get a simple proof of the famous Bautin
theorem on the cyclicity of the quadratic system.

</DOC>
<DOC>
<DOCNO> 170685 </DOCNO>
Multi-Dimensional Hermite Polynomials in Quantum Optics


  We study a class of optical circuits with vacuum input states consisting of
Gaussian sources without coherent displacements such as down-converters and
squeezers, together with detectors and passive interferometry (beam-splitters,
polarisation rotations, phase-shifters etc.). We show that the outgoing state
leaving the optical circuit can be expressed in terms of so-called
multi-dimensional Hermite polynomials and give their recursion and
orthogonality relations. We show how quantum teleportation of photon
polarisation can be modelled using this description.

</DOC>
<DOC>
<DOCNO> 68725 </DOCNO>
Sensitivity to effective electroweak couplings in single top production


  This paper has been withdrawn by the authors, due a crucial error in the
Montecarlo simulation. See hep-ph/0107112 for a correct version. If interested
in the validity of the effective-W approximation see hep-ph/0109059.

</DOC>
<DOC>
<DOCNO> 100677 </DOCNO>
Values of Brownian intersection exponents III: Two-sided exponents


  This paper determines values of intersection exponents between packs of
planar Brownian motions in the half-plane and in the plane that were not
derived in our first two papers. For instance, it is proven that the exponent
$\xi (3,3)$ describing the asymptotic decay of the probability of
non-intersection between two packs of three independent planar Brownian motions
each is $(73-2 \sqrt {73}) / 12$. More generally, the values of $\xi (w_1,
>..., w_k)$ and $\tx (w_1', ..., w_k')$ are determined for all $ k \ge 2$,
$w_1, w_2\ge 1$, $w_3, ...,w_k\in[0,\infty)$ and all
$w_1',...,w_k'\in[0,\infty)$. The proof relies on the results derived in our
first two papers and applies the same general methods. We first find the
two-sided exponents for the stochastic Loewner evolution processes in a
half-plane, from which the Brownian intersection exponents are determined via a
universality argument.

</DOC>
<DOC>
<DOCNO> 40680 </DOCNO>
Polarized structure functions of the deuteron


  Physics of spin-1 hadron is an unexplored topic in the high-energy region
although spin-1/2 physics has been well investigated in the last decade. It is
important to test our knowledge of hadron spin structure in a quite different
field of spin physics. We discuss tensor structure functions, which do not
exist for the spin-1/2 nucleon, in lepton scattering and in hadron reactions
such as the polarized proton-deuteron Drell-Yan process.

</DOC>
<DOC>
<DOCNO> 71026 </DOCNO>
The mixing of the f0(1370), f0(1500) and f0(1710) and the search for the


  For the first time a complete data set of the two-body decays of the
f0(1370), f0(1500) and f0(1710) into all pseudoscalar mesons is available. The
implications of these data for the flavour content for these three f0 states is
studied. We find that they are in accord with the hypothesis that the scalar
glueball of lattice QCD mixes with the qqbar nonet that also exists in its
immediate vicinity. We show that this solution also is compatible with the
relative production strengths of the f0(1370), f0(1500) and f0(1710) in pp
central production, ppbar annihilations and J/psi radiative decays.

</DOC>
<DOC>
<DOCNO> 71480 </DOCNO>
Studying the scale and q^2 dependence of K^+-->pi^+e^+e^- decay


  We extract the K^+-->pi^+e^+e^- amplitude scale at q^2=0 from the recent
Brookhaven E865 high-statistics data. We find that the q^2=0 scale is fitted in
excellent agreement with the theoretical long-distance amplitude. Lastly, we
find that the observed q^2 shape is explained by the combined effect of the
pion and kaon form-factor vector-meson-dominance rho, omega and phi poles, and
a charged pion loop coupled to a virtual photon-->e^+e^- transition.

</DOC>
<DOC>
<DOCNO> 69613 </DOCNO>
New shapes of light-cone distributions of the transversely polarized


  We re-analyze the leading twist light-cone distributions for transversely
polarized \rho-, \rho'- and b_1-mesons in the framework of QCD sum rules with
nonlocal condensates. Using different kinds of sum rules to obtain reliable
predictions, we estimate the 2-, 4-, 6- and 8-th moments for transversely
polarized \rho- and \rho'-meson distributions and re-estimate tensor couplings
f^T_{\rho,\rho',b_1}. We stress that the results of standard sum rules also
support our estimation of the second moment of the transversely polarized
\rho-meson distribution. New models for light-cone distributions of these
mesons are constructed. Phenomenological consequences from these distributions
are briefly discussed. Our results are compared with those found by Ball and
Braun (1996), and the latter is shown to be incomplete.

</DOC>
<DOC>
<DOCNO> 170495 </DOCNO>
Quantum information processing


  Short review article on quantum information processing accepted for
Supplement III, Encyclopaedia of Mathematics (publication expected Summer
2001). See also http://www.wkap.nl/series.htm/ENM

</DOC>
<DOC>
<DOCNO> 101099 </DOCNO>
Perron-Frobenius Theory for Positive Maps on Trace Ideals


  This article provides sufficient conditions for positive maps on the Schatten
classes $\mathcal J_{p}, 1\le p<\infty$ of bounded operators on a separable
Hilbert space such that a corresponding Perron-Frobenius theorem holds. With
applications in quantum information theory in mind sufficient conditions are
given for a trace preserving, positive map on $\mathcal J_{1}$, the space of
trace class operators, to have a unique, strictly positive density matrix which
is left invariant under the map. Conversely to any given strictly positive
density matrix there are trace preserving, positive maps for which the density
matrix is the unique Perron-Frobenius vector.

</DOC>
<DOC>
<DOCNO> 13751 </DOCNO>
Efficient Total Energy Calculations from Self-Energy Models


  We propose a new method for calculating total energies of systems of
interacting electrons, which requires little more computational resources than
standard density-functional theories. The total energy is calculated within the
framework of many-body perturbation theory by using an efficient model of the
self-energy, that nevertheless retains the main features of the exact operator.
The method shows promising performance when tested against quantum Monte Carlo
results for the linear response of the homogeneous electron gas and structural
properties of bulk silicon.

</DOC>
<DOC>
<DOCNO> 99725 </DOCNO>
Nambu structures and integrable 1-forms


  Some years ago Mosh\'e Flato pointed up that it could be interesting to
develop the Nambu's idea to generalize Hamiltonian mechanic. An interesting new
formalism in that direction was proposed by T. Takhtajan.
 His theory gave new perspectives concerning deformation quantization, and many
authors have developed its mathematical features.
  The purpose of this paper is to show that this theory, at first designated to
physic, gives a new point of view for the study of singularities of integrable
1-forms. Namely, we will prove that any integrable 1-form which vanishes at a
point and has a non-zero linear part at this point is, up to multiplication by
a non-vanishing function, the formal pull-back of a two dimensional 1-form. We
also obtain a classification of quadratic integrable 1-forms.

</DOC>
<DOC>
<DOCNO> 118505 </DOCNO>
Extended X-ray emission in the radio loud galaxy 3C 382


  ROSAT/HRI observations of the powerful radio-loud galaxy 3C382 reveal
extended X-ray emission associated with the source. On the basis of this new
spatial component, a previous ROSAT/PSPC spectral analysis of the source is
revised. Allowing for the presence of an additional thermal component in the
PSPC spectrum, the non-thermal component is found to be compatible with the
extrapolation of the well defined 3C382 - 2-10 keV - power-law spectrum into
the soft X-rays. The thermal -extended- component would then account for the
soft excess emission previously reported for this source. The origin of this
thermal component is not clear. Its luminosity compares with that of rich Abell
clusters; yet, the galaxy environment in 3C382 appears of moderate optical
richness. An alternative is that it is due to a massive extended gaseous
atmosphere sustained by the deep gravitational potential well of 3C382.

</DOC>
<DOC>
<DOCNO> 121265 </DOCNO>
Rapidly rotating strange stars


  We study effects of the strange quark mass and of the QCD coupling constant
in the MIT bag model of quark matter with lowest order quark-gluon interactions
on the rapid rotation of strange stars. The influence of rotation on global
parameters of strange stars is greater than in the case of the neutron star
models. We show that independently of the strange quark mass and the coupling
constans the ratio of the rotational kinetic energy to the absolute value of
the gravitational potential energy for rotating strange stars is significantly
higher than for ordinary neutron stars. This might indicate that rapidly
rotating strange stars could be important sources of gravitational waves.

</DOC>
<DOC>
<DOCNO> 150479 </DOCNO>
A Comment on the Holographic Renormalization Group and the Soft Dilaton


  The equivalence between the holographic renormalization group and the soft
dilaton theorem is shown for a class of wrapped metrics solutions of the string
beta function equations for the bosonic string.

</DOC>
<DOC>
<DOCNO> 120956 </DOCNO>
Absolute dimensions of the unevolved B-type eclipsing binary GG Orionis


  We present photometric observations in B and V as well as spectroscopic
observations of the detached, eccentric 6.6-day double-lined eclipsing binary
GG Ori, a member of the Orion OB1 association. Absolute dimensions of the
components, which are virtually identical, are determined to high accuracy
(better than 1% in the masses and better than 2% in the radii) for the purpose
of testing various aspects of theoretical modeling. We obtain M(A) = 2.342 +/-
0.016 solar masses and R(A) = 1.852 +/- 0.025 solar radii for the primary, and
M(B) = 2.338 +/- 0.017 solar masses and R(B) = 1.830 +/- 0.025 solar radii for
the secondary. The effective temperature of both stars is 9950 +/- 200 K,
corresponding to a spectral type of B9.5. GG Ori is very close to the ZAMS, and
comparison with current stellar evolution models gives ages of 65-82 Myr or 7.7
Myr depending on whether the system is considered to be burning hydrogen on the
main sequence or still in the final stages of pre-main sequence contraction. We
have detected apsidal motion in the binary at a rate of dw/dt = 0.00061 +/-
0.00025 degrees per cycle, corresponding to an apsidal period of U = 10700 +/-
4500 yr. A substantial fraction of this (approximately 70%) is due to the
contribution from General Relativity.

</DOC>
<DOC>
<DOCNO> 9517 </DOCNO>
Destruction of Bose-Einstein condensate by strong interactions


  We study exactly soluble system of trapped bosonic particles interacting by a
model harmonic forces. The model allows for detailed examination of the order
parameter (condensate wave function) as well as concept of the off-diagonal and
diagonal order. We analyze the effect of interactions on the condensate and
show that sufficiently strong interactions, attractive or repulsive, lead to
destruction of the condensate. In the thermodynamic limit this destruction has
a critical character. It is shown that the existence of the coherent state of
bosons is related to existence of two length scales determined by one- and
two-particle reduced density matrices. The condensate can exist only if the two
length scales are of the same order. Interactions, both repulsive and
attractive, change their relative size which may lead to destruction of
coherence in the system and depletion of the condensate. We suggest that this
scenario is model independent.

</DOC>
<DOC>
<DOCNO> 69959 </DOCNO>
On the nature of cosmic rays above the Greisen--Zatsepin--Kuz'min cut


  A re-examination of the atmospheric cascade profile of the highest energy
cosmic ray is presented. The study includes air-shower simulations considering
different cross sections, particle multiplicity and variation of the
hadronic-event-generator to model interactions above 200 GeV. The analysis
provides evidence that a medium mass nucleus primary reproduces the shower
profile quite well. This result does not support the idea, increasingly popular
at present, that the highest energy particles are protons, derived from the
decay of supermassive relic particles. On the other hand, we show that debris
of relativistic super-heavy nuclei, which can survive a 100 Mpc journey through
the primeval radiation are likely to generate such a kind of cascade.

</DOC>
<DOC>
<DOCNO> 85598 </DOCNO>
Noninertial quantum mechanical fluctuations


  Zero point quantum fluctuations as seen from non-inertial reference frames
are of interest for several reasons. In particular, because phenomena such as
Unruh radiation (acceleration radiation) and Hawking radiation (quantum leakage
from a black hole) depend intrinsically on both quantum zero-point fluctuations
and some appropriate notion of an accelerating vacuum state, any experimental
test of zero-point fluctuations in non-inertial frames is implicitly a test of
the foundations of quantum field theory, and the Unruh and Hawking effects

</DOC>
<DOC>
<DOCNO> 174530 </DOCNO>
Study of Residual Product Nuclide Yields in 1.0 GeV Proton-Irradiated


  113 residual product nuclide yields in a 1.0 GeV proton-irradiated thin
monoisotopic 208-Pb sample and 107 residual product nuclide yields in a 2.6 GeV
proton-irradiated nat-W sample have been measured and simulated by 8 different
codes. The irradiations were made using proton beams extracted from the ITEP
synchrotron. The nuclide yields were gamma-spectrometered directly using a
high-resolution Ge-detector. The gamma-spectra were processed by the GENIE-2000
code. The ITEP-developed SIGMA code was used together with the PCNUDAT nuclear
decay database to identify the gamma-lines and to determine the cross-sections.
The 27-Al(p,x)Na-22 reaction was used to monitor the proton flux. The measured
yields are compared with calculation the LAHET (with ISABEL and Bertini
options), CEM95, CEM2k, CASCADE, CASCADE/INPE, INUCL, and YIELDX codes.
Estimates of the mean deviation factor are used to demonstrate the predictive
power of the codes. The results obtained may be of interest in studying the
parameters of the Pb and W target modules of the hybrid Accelerator-Driven
System (ADS) facilities.

</DOC>
<DOC>
<DOCNO> 12671 </DOCNO>
Exactly Solvable Single Lane Highway Traffic Model With Tollbooths


  Tolls are collected on many highways as a means of traffic control and
revenue generation. However, the presence of tollbooths on highway surely slows
down traffic flow. Here, we investigate how the presence of tollbooths affect
the average car speed using a simple-minded single lane deterministic discrete
traffic model. More importantly, the model is exactly solvable.

</DOC>
<DOC>
<DOCNO> 12139 </DOCNO>
Incomplete nonextensive statistics and zeroth law of thermodynamics


  We show that the zeroth law of thermodynamics holds within an alternative
version of nonextensive statistical mechanics based on {\it incomplete
probability distribution}. The generalized zeroth law leads to a generalized
definition of thermodynamic functions which are possible to be used for systems
with important nonextensivity (nonadditivity) in energy, volume or other
external variables.

</DOC>
<DOC>
<DOCNO> 10793 </DOCNO>
Quiet and Noisy Metastable Voltage States in High-Tc Superconductors


  The interaction between the telegraph noise and background voltage
fluctuations in the current induced dissipative state of high-Tc BiSrCaCuO thin
films has been investigated. Experimental time records of the voltage drop
across current biased thin film strips show markedly different background noise
traces in the up and down telegraph states. Detailed analysis demonstrates that
fluctuations around the telegraph voltage levels are due to a unique background
noise process. The apparent quiet and noisy voltage states are due only to
differences in the effective frequency bandwidth at which background noise is
seen at distinct telegraph levels. Changes of the background noise variance
ratio with changing bias current follow changes of the statistical average
lifetimes of the random telegraph process.

</DOC>
<DOC>
<DOCNO> 100164 </DOCNO>
An improved bound for the Minkowski dimension of Besicovitch sets in


  We use geometrical combinatorics arguments, including the ``hairbrush'' and
x-ray arguments of Wolff and the sticky/plany/grainy analysis of Katz, Laba,
and Tao, to show that Besicovitch sets in R^n have Minkowski dimension at least
(n+2)/2 + \eps_n for all n > 3, where \eps_n > 0 is an absolute constant
depending only on n. This complements the results of Katz, Laba, and Tao, which
established the same result for n=3, and of Bourgain and Katz-Tao, arithmetic
combinatorics techniques to establish the result for n > 8. In contrast to
previous work, our arguments will be purely geometric and do not require
arithmetic combinatorics.

</DOC>
<DOC>
<DOCNO> 99409 </DOCNO>
An explicit formula for PBW quantization


  Let $k$ be a field of characteristic zero, $\g$ a $k$-Lie algebra,
$e:S\g@>>>U\g$ the symmetrization map. The PBW quantization is the one
parameter family of associative products: $$ x\star_t y=\sum_{p=0}^\infty
B_p(x,y)t^p\qquad (t\in k) $$ where $B_p$ is the homogeneous component of
degree $-p$ of the map $B:S\g\otimes_kS\g@>>>S\g$, $B(x,y)=e^{-1}(exey)$. In
this paper we give an explicit formula for $B$. As an application, we prove
that for each $p\ge 0$, $B_p$ is a bidifferential operator of order $\le p$.

</DOC>
<DOC>
<DOCNO> 9847 </DOCNO>
A dual point description of mesoscopic superconductors


  We present an analysis of the magnetic response of a mesoscopic
superconductor, i.e. a system of sizes comparable to the coherence length and
to the London penetration depth. Our approach is based on special properties of
the two dimensional Ginzburg-Landau equations, satisfied at the dual point
$(\kappa = \frac{1}{\sqrt{2}}).$ Closed expressions for the free energy and the
magnetization of the superconductor are derived. A perturbative analysis in the
vicinity of the dual point allows us to take into account vortex interactions,
using a new scaling result for the free energy. In order to characterize the
vortex/current interactions, we study vortex configurations that are out of
thermodynamical equilibrium. Our predictions agree with the results of recent
experiments performed on mesoscopic aluminium disks.

</DOC>
<DOC>
<DOCNO> 99734 </DOCNO>
Conditions satisfied by characteristic polynomials in fields and


  Suppose E/F is a field extension. We ask whether or not there exists an
element of E whose characteristic polynomial has one or more zero coefficients
in specified positions. We show that the answer is frequently ``no''. We also
prove similar results for division algebras and show that the universal
division algebra of degree n does not have an element of trace 0 and norm 1.

</DOC>
<DOC>
<DOCNO> 99408 </DOCNO>
Symplectic realizations of bihamiltonian structures


  A method of constructing a class of bihamiltonian structures is presented.
Elements of this class are generalizations of the so-called bihamiltonian
structures of general position on odd-dimensional manifolds. The method
consists in a simultaneous reduction of both the real and imaginary parts of a
complex symplectic form. Necessary and sufficient conditions of getting a
bihamiltonian structure from the mentioned class are obtained. The second part
of the paper is devoted to a series of examples of such a reduction related to
semisimple Lie algebras.

</DOC>
<DOC>
<DOCNO> 12628 </DOCNO>
Magnetic properties of (VO)_2P_2O_7: two-plane structure and spin-phonon


  Detailed experiments on single-crystal (VO)_2P_2O_7 continue to reveal new
and unexpected features. We show that a model composed of two, independent
planes of spin chains with frustrated magnetic coupling is consistent with
nuclear magnetic resonance and inelastic neutron scattering measurements. The
pivotal role of PO_4 groups in mediating intrachain exchange interactions
explains both the presence of two chain types and their extreme sensitivity to
certain lattice vibrations, which results in the strong magnetoelastic coupling
observed by light scattering. We compute the respective modifications of the
spin and phonon dynamics due to this coupling, and illustrate their observable
consequences on the phonon frequencies, magnon dispersions, static
susceptibility and specific heat.

</DOC>
<DOC>
<DOCNO> 84316 </DOCNO>
Relationships between various characterisations of wave tails


  One can define several properties of wave equations that correspond to the
absence of tails in their solutions, the most common one by far being Huygens'
principle. Not all of these definitions are equivalent, although they are
sometimes assumed to be. We analyse this issue in detail for linear scalar
waves, establishing some relationships between the various properties. Huygens'
principle is almost always equivalent to the characteristic propagation
property, and in two spacetime dimensions the latter is equivalent to the
zeroth order progressing wave propagation property. Higher order progressing
waves in general do have tails, and do not seem to admit a simple physical
characterisation, but they are nevertheless useful because of their close
association with exactly solvable two-dimensional equations.

</DOC>
<DOC>
<DOCNO> 99766 </DOCNO>
Cascade Connection of Multiparametric Linear Systems and a Conservative


  We introduce the notion of cascade connection of multiparametric discrete
time-invariant linear dynamical systems with unit delay. This allows us to
construct the explicit example of conservative realization of a decomposable
operator-valued function $\theta (z_1, z_2)=\theta_2(z_2)\theta_1(z_1)$, where
$\theta_1$ and $\theta_2$ are inner operator-valued functions on the unit disk,
vanishing at zero, and discuss some properties of such realization.

</DOC>
<DOC>
<DOCNO> 121159 </DOCNO>
Particle reacceleration in Coma cluster: radio properties and hard X-ray


  The radio spectral index map of the Coma halo shows a progressive steepening
of the spectral index with increasing radius. Such a steepening cannot be
simply justified by models involving continuous injection of fresh particles in
the Coma halo or by models involving diffusion of fresh electrons from the
central regions. We propose a {\it two phase} model in which the relativistic
electrons injected in the Coma cluster by some processes (starbursts, AGNs,
shocks, turbulence) during a {\it first phase} in the past are systematically
reaccelerated during a {\it second phase} for a relatively long time ($\sim$ 1
Gyr) up to the present time. We show that for reacceleration time scales of
$\sim 0.1$ Gyr this hypothesis can well account for the radio properties of
Coma C. For the same range of parameters which explain Coma C we have
calculated the expected fluxes from the inverse Compton scattering of the CMB
photons finding that the hard X-ray tail discovered by BeppoSAX may be
accounted for by the stronger reacceleration allowed by the model. The
possibility of extending the main model assumptions and findings to the case of
the other radio haloes is also discussed, the basic predictions being
consistent with the observations.

</DOC>
<DOC>
<DOCNO> 14169 </DOCNO>
Materials of the round table ``Phase transitions and critical phenomena:


  The paper contains materials of the discussion concerning phase transitions
and critical phenomena which took place during the Workshop on modern problems
of soft matter theory (Aug. 27 -- Aug. 31, 2000, Lviv, Ukraine).

</DOC>
<DOC>
<DOCNO> 118112 </DOCNO>
First results of the air shower experiment KASCADE


  The main goals of the KASCADE (KArlsruhe Shower Core and Array DEtector)
experiment are the determination of the energy spectrum and elemental
composition of the charged cosmic rays in the energy range around the knee at
ca. 5 PeV. Due to the large number of measured observables per single shower a
variety of different approaches are applied to the data, preferably on an
event-by-event basis. First results are presented and the influence of the
high-energy interaction models underlying the analyses is discussed.

</DOC>
<DOC>
<DOCNO> 151893 </DOCNO>
y-Deformed BPS Dp- branes On a Surface In a Calabi-Yau Threefold


  Using y-deformed algebraic geometric techniques the y-deformed Mukay vector
of RR-charges of the y-deformed BPS Dp-branes localized on a surface in a
Calabi-Yau threefold. The formulas that are obtained here are generalizations
of the formulas of the fourth section of the preprint hep-th/0007243 .

</DOC>
<DOC>
<DOCNO> 83234 </DOCNO>
Data Streams from the Low Frequency Instrument On-Board the Planck


  The expected data rate produced by the Low Frequency Instrument (LFI) planned
to fly on the ESA Planck mission in 2007, is over a factor 8 larger than the
bandwidth allowed by the spacecraft transmission system to download the LFI
data. We discuss the application of lossless compression to Planck/LFI data
streams in order to reduce the overall data flow. We perform both theoretical
analysis and experimental tests using realistically simulated data streams in
order to fix the statistical properties of the signal and the maximal
compression rate allowed by several lossless compression algorithms. We studied
the influence of signal composition and of acquisition parameters on the
compression rate Cr and develop a semiempirical formalism to account for it.
The best performing compressor tested up to now is the arithmetic compression
of order 1, designed for optimizing the compression of white noise like
signals, which allows an overall compression rate <Cr> = 2.65 +/- 0.02. We find
that such result is not improved by other lossless compressors, being the
signal almost white noise dominated. Lossless compression algorithms alone will
not solve the bandwidth problem but needs to be combined with other techniques.

</DOC>
<DOC>
<DOCNO> 11136 </DOCNO>
Interaction of Mesoscopic Magnetic Textures with Superconductors


  We analyze magnetic textures in a thin magnetic film and screening currents
induced by these textures in a superconducting film. The films are supposed to
be parallel and close to each other, but interact only via magnetic fields. We
consider also vortices inside superconducting film and their interaction with
magnetic textures. As examples of magnetic textures we consider magnetic dot
and magnetic vortex. We derive the condition at which spontaneous formation of
a vortex or a coupled vortex-magnetic defect is energetically favorable. It is
proven that the normal component of magnetic field generated by a magnetic dot
changes sign in the presence of the superconducting vortex.

</DOC>
<DOC>
<DOCNO> 120251 </DOCNO>
Population effects on the Red Giant Clump absolute magnitude, and


  (Abridged) The red giant clump has been recently argued to be a reliable
distance indicator for the galaxies in the Local Group. We re-address the
problem of the systematic magnitude differences (DeltaM_I) between the local
clump revealed by Hipparcos, and the clump stars observed in distant galaxies.
First, we present tables and equations with the theoretically-predicted clump
M_I as a function of age and metallicity, that allow the computation of
DeltaM_I for any given galaxy model. We then explain in some detail what
determines the distribution of masses, ages, and metallicities of clump stars
in a galaxy. We point out that in galaxies with recent/ongoing star formation,
the age distribution of clump stars is strongly biased toward younger (1-3 Gyr)
ages, and hence toward higher metallicities. Obviously, this does not happen in
galaxies with predominantly old stellar populations. We construct a model for
the local clump that is shown to produce distributions of metallicities,
colours, and magnitudes, similar to those derived from spectroscopic and
Hipparcos data. Bulge, Magellanic Clouds, and Carina dSph models are used to
analyse the values of DeltaM_I for these systems. We show how the clump-RR
Lyrae data is well reproduced by the models. However, despite this, the models
indicate that the linear DeltaM_I vs. [Fe/H] relations that have been derived
from the data are not general. Finally, we provide revised clump distances to
the Bulge, Magellanic Clouds, and Carina dSph. The largest DeltaM_I values are
found for the Magellanic Clouds and Carina dSph, which turn out to be located
at distance moduli 0.2-0.3 mag longer than indicated by works which ignore
population effects. The Galactic Bulge, instead, may be slightly closer (0.1
mag) than indicated by previous works based on the red clump.

</DOC>
<DOC>
<DOCNO> 9343 </DOCNO>
Contributions of spontaneous phase slippage to linear and non-linear


  In the Peierls state very thin samples of TaS_3 (cross-section area \sim
10^{-3} mkm^2) are found to demonstrate smearing of the I-V curves near the
threshold field. With approaching the Peierls transition temperature, T_P, the
smearing evolves into smooth growth of conductance from zero voltage
interpreted by us as the contribution of fluctuations to the non--linear
conductance. We identify independently the fluctuation contribution to the
linear conductance near T_P. Both linear and non-linear contributions depend on
temperature with close activation energies \sim (2 - 4) x 10^3 K and apparently
reveal the same process. We reject creep of the {\it continuous} charge-density
waves (CDWs) as the origin of this effect and show that it is spontaneous phase
slippage that results in creep of the CDW. A model is proposed accounting for
both the linear and non-linear parts of the fluctuation conduction up to T_P.

</DOC>
<DOC>
<DOCNO> 84817 </DOCNO>
Cauchy-Characteristic Matching In General Relativity


  From Einstein's theory we know that besides the electromagnetic spectrum,
objects like quasars, active galactic nuclei, pulsars and black holes also
generate a physical signal of purely gravitational nature. The actual form of
the signal is impossible to determine analytically, which lead to use of
numerical methods.
  Two major approaches emerged. The first one formulates the gravitational
radiation problem as a standard Cauchy initial value problem, while the other
approach uses a Characteristic Initial value formulation. In the strong field
region, where caustics in the wavefronts are likely to form, the Cauchy
formulation is more advantageous. On the other side, the Characteristic
formulation is uniquely suited to study radiation problems because it describes
space-time in terms of radiation wavefronts.
  The fact that the advantages and disadvantages of these two systems are
complementary suggests that one may want to use the two of them together. In a
full nonlinear problem it would be advantageous to evolve the inner (strong
field) region using Cauchy evolution and the outer (radiation) region with the
Characteristic approach. Cauchy Characteristic Matching enables one to evolve
the whole space-time matching the boundaries of Cauchy and Characteristic
evolution. The methodology of Cauchy Characteristic Matching has been
successful in numerical evolution of the spherically symmetric
Klein-Gordon-Einstein field equations as well as for 3-D non-linear wave
equations. In this thesis the same methodology is studied in the context of the
Einstein equations.

</DOC>
<DOC>
<DOCNO> 118983 </DOCNO>
NGC1333/IRAS4: A multiple star formation laboratory


  We present SCUBA observations of the protomultiple system NGC1333/IRAS4 at
450um and 850um. The 850um map shows significant extended emission which is
most probably a remnant of the initial cloud core. At 450um, the component 4A
is seen to have an elongated shape suggestive of a disk. Also we confirm that
in addition to the 4A and 4B system, there exists another component 4C, which
appears to lie out of the plane of the system and of the extended emission.
Deconvolution of the beam reveals a binary companion to IRAS4B. Simple
considerations of binary dynamics suggest that this triple 4A-4BI-4BII system
is unstable and will probably not survive in its current form. Thus IRAS4
provides evidence that systems can evolve from higher to lower multiplicity as
they move towards the main sequence. We construct a map of spectral index from
the two wavelengths, and comment on the implications of this for dust evolution
and temperature differences across the map. There is evidence that in the
region of component 4A the dust has evolved, probably by coagulating into
larger or more complex grains. Furthermore, there is evidence from the spectral
index maps that dust from this object is being entrained in its associated
outflow.

</DOC>
<DOC>
<DOCNO> 119055 </DOCNO>
Cluster Mass Reconstruction by a Weak Shear Field


  The tidal gravitational field of galaxy clusters causes a coherent distortion
of the images of background sources.
 Since the distribution of image distortions, namely the shear field, traces
the local gravitational potential of a deflector, it can be used to reconstruct
the two-dimensional mass distribution of clusters of galaxies.
 Moreover, the shear field can provide unique information on the redshift
distribution of high-redshift galaxies.
 In this review we summarize recently-developed parameter-free methods of
cluster-mass reconstruction based on the shear field, and we apply a
mass-reconstruction method to the cluster Abell 370 at redshift 0.375.

</DOC>
<DOC>
<DOCNO> 170162 </DOCNO>
Information, disturbance and Hamiltonian quantum feedback control


  We consider separating the problem of designing Hamiltonian quantum feedback
control algorithms into a measurement (estimation) strategy and a feedback
(control) strategy, and consider optimizing desirable properties of each under
the minimal constraint that the available strength of both is limited. This
motivates concepts of information extraction and disturbance which are distinct
from those usually considered in quantum information theory. Using these
concepts we identify an information trade-off in quantum feedback control.

</DOC>
<DOC>
<DOCNO> 40563 </DOCNO>
Search for a Higgs Boson Decaying into Two Photons with the L3 Detector


  A search is performed for a Higgs boson, decaying into two photons, using the
L3 data collected at centre of mass energies between $\sqrt s$ = 189 and 202
GeV, corresponding to an integrated luminosity of 400 pb$^{-1}$. The processes
$e^{+}e^{-}\to {Zh} \to {q} \bar{q} \gamma \gamma $, $e^{+}e^{-}\to {Zh} \to
\nu \bar{\nu} \gamma \gamma $, $e^{+}e^{-}\to {Zh} \to {l}^{+} {l}^{-} \gamma
\gamma $ are considered. The observed data are found to be consistent with the
expected background from standard physics processes. Limits on the branching
fraction of the Higgs boson decay into two photons as a function of the Higgs
mass are shown and a lower mass limit on a fermiophobic Higgs is derived.

</DOC>
<DOC>
<DOCNO> 151082 </DOCNO>
Cliffordons


  At higher energies the present complex quantum theory with its unitary group
might expand into a real quantum theory with an orthogonal group, broken by an
approximate $i$ operator at lower energies. Implementing this possibility
requires a real quantum double-valued statistics. A Clifford statistics,
representing a swap (12) by a difference $\gamma_1-\gamma_2$ of Clifford units,
is uniquely appropriate. Unlike the Maxwell-Boltzmann, Fermi-Dirac,
Bose-Einstein, and para- statistics, which are tensorial and single-valued, and
unlike anyons, which are confined to two dimensions, Clifford statistics are
multivalued and work for any dimensionality. Nayak and Wilczek proposed a
Clifford statistics for the fractional quantum Hall effect. We apply them to
toy quanta here. A complex-Clifford example has the energy spectrum of a system
of spin-1/2 particles in an external magnetic field. This supports the proposal
that the double-valued rotations --- spin --- seen at current energies might
arise from double-valued permutations --- swap --- to be seen at higher
energies. Another toy with real Clifford statistics illustrates how an
effective imaginary unit $i$ can arise naturally within a real quantum theory.

</DOC>
<DOC>
<DOCNO> 13481 </DOCNO>
Polaron features of the one-dimensional Holstein Molecular Crystal Model


  The polaron features of the one-dimensional Holstein Molecular Crystal Model
are investigated by improving a variational method introduced recently and
based on a linear superposition of Bloch states that describe large and small
polaron wave functions. The mean number of phonons, the polaron kinetic energy,
the electron-phonon local correlation function, and the ground state spectral
weight are calculated and discussed. A crossover regime between large and small
polaron for any value of the adiabatic parameter $\omega_0/t$ is found and a
polaron phase diagram is proposed.

</DOC>
<DOC>
<DOCNO> 40106 </DOCNO>
Jet Fragmentation and MLLA


  Recent CDF results on inclusive momentum distributions and multiplicities of
particles in restricted cones around jets are compared to predictions using the
Modified Leading Log Approximation. We found that MLLA gives a very reasonable
description of jet fragmentation for a wide range of energies. Model parameters
are extracted separately from the multiplicity and from the shape of the
momentum distributions and are found to agree. The ratio of charged particle
multiplicities in gluon and quark jets measured in the context of MLLA is
compared to the model-independent result and also found to agree.

</DOC>
<DOC>
<DOCNO> 71027 </DOCNO>
Braneworld gravity: Influence of the moduli fields


  We consider the case of a generic braneworld geometry in the presence of one
or more moduli fields (e.g., the dilaton) that vary throughout the bulk
spacetime. Working in an arbitrary conformal frame, using the generalized
junction conditions of gr-qc/0008008 and the Gauss--Codazzi equations, we
derive the effective ``induced'' on-brane gravitational equations. As usual in
braneworld scenarios, these equations do not form a closed system in that the
bulk can exchange both information and stress-energy with the braneworld. We
work with an arbitrary number of moduli fields described by an arbitrary sigma
model, with arbitrary curvature couplings, arbitrary self interactions, and
arbitrary dimension for the bulk. (The braneworld is always codimension one.)
Among the novelties we encounter are modifications of the on-brane
stress-energy conservation law, anomalous couplings between on-brane gravity
and the trace of the on-brane stress-energy tensor, and additional
possibilities for modifying the on-brane effective cosmological constant. After
obtaining the general stress-energy ``conservation'' law and the ``induced
Einstein equations'' we particularize the discussion to two particularly
attractive cases: for a (n-2)-brane in ([n-1]+1) dimensions we discuss both the
effect of (1) generic variable moduli fields in the Einstein frame, and (2) the
effect of a varying dilaton in the string frame.

</DOC>
<DOC>
<DOCNO> 118353 </DOCNO>
Geometric Gaussianity and Non-Gaussianity in the Cosmic Microwave


  In this paper, Gaussianity of eigenmodes and non-Gaussianity in the Cosmic
Microwave Background (CMB) temperature fluctuations in two smallest compact
hyperbolic (CH) models are investigated. First, it is numerically found that
the expansion coefficients of low-lying eigenmodes on the two CH manifolds
behave as if they are Gaussian random numbers at almost all the places. Next,
non-Gaussianity of the temperature fluctuations in the (l,m) space in these
models is studied. Assuming that the initial fluctuations are Gaussian, the
real expansion coefficients b_{l m} of the temperature fluctuations in the sky
are found to be distinctively non-Gaussian. In particular, the cosmic variances
are found to be much larger than that for Gaussian models. On the other hand,
the anisotropic structure is vastly erased if one averages the fluctuations at
a number of different observing points because of the Gaussian
pseudo-randomness of the eigenmodes. Thus the dominant contribution to the
two-point correlation functions comes from the isotropic terms described by the
angular power spectra C_l. Finally, topological quantities: the total length
and the genus of isotemperature contours are investigated. The variances of
total length and genus at high and low threshold levels are found to be
considerably larger than that of Gaussian models while the means almost agree
with them.

</DOC>
<DOC>
<DOCNO> 84805 </DOCNO>
Response of Interferometric Detectors to Scalar Gravitational Waves


  We rigorously analyze the frequency response functions and antenna
sensitivity patterns of three types of interferometric detectors to scalar mode
of gravitational waves which is predicted to exist in the scalar-tensor theory
of gravity. By a straightforward treatment, we show that the antenna
sensitivity pattern of the simple Michelson interferometric detector depends
strongly on the wave length $\lambda_{\rm SGW}$ of the scalar mode of
gravitational waves if $\lambda_{\rm SGW}$ is comparable to the arm length of
the interferometric detector. For the Delay-Line and Fabry-Perot
interferometric detectors with arm length much shorter than $\lambda_{\rm
SGW}$, however, the antenna sensitivity patterns depend weakly on $\lambda_{\rm
SGW}$ even though $\lambda_{\rm SGW}$ is comparable to the effective path
length of those interferometers. This agrees with the result obtained by
Maggiore and Nicolis.

</DOC>
<DOC>
<DOCNO> 71944 </DOCNO>
Radion signature in $\gamma\gamma$ scattering


  We investigate the phenomenological consequences of the possible existence of
the radion at a TeV-scale for $\gamma\gamma$ scattering in the TeV range. We
find that polarized cross-sections only give possible experimental signatures
for the radion.

</DOC>
<DOC>
<DOCNO> 122612 </DOCNO>
The Interaction between the ISM and Star Formation in the Dwarf


  We present the first interferometric study of the molecular gas in the
metal-poor dwarf starburst galaxy NGC 4214. Our map of the 12CO(1-0) emission,
obtained at the OVRO millimeter array, reveals an unexpected structural wealth.
We detected three regions of molecular emission in the north-west (NW),
south-east (SE) and centre of NGC 4214 which are in very different and distinct
evolutionary stages (total molecular mass: 5.1 x 10^6 M_sun). These differences
are apparent most dramatically when the CO morphologies are compared to optical
ground based and HST imaging: massive star formation has not started yet in the
NW region; the well-known starburst in the centre is the most evolved and star
formation in the SE complex started more recently. We derive a star formation
efficiency of 8% for the SE complex. Using high--resolution VLA observations of
neutral hydrogen HI and our CO data we generated a total gas column density map
for NGC 4214 (HI + H_2). No clear correlation is seen between the peaks of HI,
CO and the sites of ongoing star formation. This emphasizes the irregular
nature of dwarf galaxies. The HI and CO velocities agree well, so do the
H-alpha velocities. In total, we cataloged 14 molecular clumps in NGC 4214. Our
results from a virial mass analysis are compatible with a Galactic CO-to-H_2
conversion factor for NGC 4214 (lower than what is usually found in metal-poor
dwarf galaxies).

</DOC>
<DOC>
<DOCNO> 13932 </DOCNO>
Dynamics of surface steps


  In the framework of SOS models, the dynamics of isolated and pairs of surface
steps of monoatomic height is studied, for step--edge diffusion and for
evaporation kinetics, using Monte Carlo techniques. In particular, various
interesting crossover phenomena are identified. Simulational results are
compared, especially, to those of continuum theories and random walk
descriptions.

</DOC>
<DOC>
<DOCNO> 116515 </DOCNO>
Molecular Dynamics Studies of Sequence-directed Curvature in Bending


  The macroscopic curvature induced in the double helical B-DNA by regularly
repeated adenine tracts (A-tracts) plays an exceptional role in structural
studies of DNA because this effect presents the most well-documented example of
sequence specific conformational modulations. Recently, a new hypothesis of its
physical origin has been put forward, based upon the results of molecular
dynamics simulations of a 25-mer fragment with three A-tracts phased with the
helical screw. Its sequence, however, had never been encountered in
experimental studies, but was constructed empirically so as to maximize the
magnitude of bending in specific computational conditions. Here we report the
results of a similar investigation of another 25-mer B-DNA fragment now with a
natural base pair sequence found in a bent locus of a minicircle DNA. It is
shown that the static curvature of a considerable magnitude and stable
direction towards the minor grooves of A-tracts emerges spontaneously in
conditions excluding any initial bias except the base pair sequence. Comparison
of the bending dynamics of these two DNA fragments reveals both qualitative
similarities and interesting differences. The results suggest that the A-tract
induced bending obtained in simulations reproduces the natural phenomenon and
validates the earlier conclusions concerning its possible mechanism.

</DOC>
<DOC>
<DOCNO> 69191 </DOCNO>
Quark and Lepton Mass Matrices with a Cyclic Permutation Invariant Form


  As an attempt to give an unified description of quark and lepton mass
matrices M_f, the following mass matrix form is proposed: the form of the mass
matrices are invariant under a cyclic permutation (f_1 \to f_2, f_2 \to f_3,
f_3 \to f_1) among the fermions f_i. The model naturally leads to the maximal
mixing between \nu_\mu and \nu_\tau, and with an additional ansatz, it leads to
the well-satisfied relations |V_{us}| \simeq \sqrt{m_d/m_s} and |V_{cb}| \simeq
\sqrt{m_d/m_b}.

</DOC>
<DOC>
<DOCNO> 120954 </DOCNO>
Imaging the Universe in 3D with the VLT: The Next Generation Field


  We present SPIFFI, the integral field spectrometer for the VLT. This
instrument allows simultaneous observation of infrared spectra in more than
1000 image points of a two dimensional field. With its set of four gratings and
a pixel scale that can be varied by a factor of ten, SPIFFI provides high
flexibility, and at the same time offers the unique possibility of diffraction
limited imaging spectroscopy at an 8m-class telescope, when fed by the adaptive
optics system MACAO. We outline the scientific drivers for building such an
instrument, the concept of image slicing, the optical design, and the
implementation of SPIFFI.

</DOC>
<DOC>
<DOCNO> 10761 </DOCNO>
The Mott Metal-Insulator transition in the half-filled Hubbard model on


  We investigate the metal-insulator transition in the half-filled Hubbard
model on a two-dimensional triangular lattice using both the
Kotliar-Ruckenstein slave-boson technique, and exact numerical diagonalization
of finite clusters. Contrary to the case of the square lattice, where the
perfect nesting of the Fermi surface leads to a metal-insulator transition at
arbitrarily small values of U, always accompanied by antiferromagnetic
ordering, on the triangular lattice, due to the lack of perfect nesting, the
transition takes place at a finite value of U, and frustration induces a
non-trivial competition among different magnetic phases. Indeed, within the
mean-field approximation in the slave-boson approach, as the interaction grows
the paramagnetic metal turns into a metallic phase with incommensurate spiral
ordering. Increasing further the interaction, a linear spin-density-wave is
stabilized, and finally for strong coupling the latter phase undergoes a
first-order transition towards an antiferromagnetic insulator. No trace of the
intermediate phases is instead seen in the exact diagonalization results,
indicating a transition between a paramagnetic metal and an antiferromagnetic
insulator.

</DOC>
<DOC>
<DOCNO> 68207 </DOCNO>
Is it possible to Measure the Weak Phase of a Penguin Diagram?


  The $b\to d$ penguin amplitude receives contributions from internal $u$, $c$
and $t$-quarks. We show that it is impossible to measure the weak phase of any
of these penguin contributions without theoretical input. However, a single
assumption involving the hadronic parameters makes it possible to obtain the
weak phase and test for the presence of new physics in the $b\to d$
flavour-changing neutral current.

</DOC>
<DOC>
<DOCNO> 13993 </DOCNO>
Roughness of Crack Interfaces in Two-Dimensional Beam Lattices


  The roughness of crack interfaces is reported in quasistatic fracture, using
an elastic network of beams with random breaking thresholds. For strong
disorders we obtain 0.86(3) for the roughness exponent, a result which is very
different from the minimum energy surface exponent, i.e., the value 2/3. A
cross-over to lower values is observed as the disorder is reduced, the exponent
in these cases being strongly dependent on the disorder.

</DOC>
<DOC>
<DOCNO> 10393 </DOCNO>
Phase Transitions in "Small" Systems - A Challenge for Thermodynamics


  Traditionally, phase transitions are defined in the thermodynamic limit only.
We propose a new formulation of equilibrium thermo-dynamics that is based
entirely on mechanics and reflects just the {\em geometry and topology} of the
N-body phase-space as function of the conserved quantities, energy, particle
number and others. This allows to define thermo-statistics {\em without the use
of the thermodynamic limit}, to apply it to ``Small'' systems as well and to
define phase transitions unambiguously also there. ``Small'' systems are
systems where the linear dimension is of the characteristic range of the
interaction between the particles. Also astrophysical systems are ``Small'' in
this sense. Boltzmann defines the entropy as the logarithm of the area
$W(E,N)=e^{S(E,N)}$ of the surface in the mechanical N-body phase space at
total energy E. The topology of S(E,N) or more precisely, of the curvature
determinant $D(E,N)=\partial^2S/\partial E^2*\partial^2S/\partial
N^2-(\partial^2S/\partial E\partial N)^2$ allows the classification of phase
transitions {\em without taking the thermodynamic limit}. The topology gives
further a simple and transparent definition of the {\em order parameter.}
Attention: Boltzmann's entropy S(E) as defined here is different from the
information entropy and can even be non-extensive and convex.

</DOC>
<DOC>
<DOCNO> 122984 </DOCNO>
A Hierarchical Triple Star System in M4


  The radio millisecond pulsar PSR B1620-26 is part of an extraordinary triple
star system in the globular cluster M4. The inner companion to the neutron star
is thought to be a white dwarf of mass m1 ~0.3 Msun in an orbit of period ~0.5
year. The nature and orbital characteristics of the second, more distant
companion, have remained a mystery for many years. A theoretical analysis of
the latest available radio pulsar timing data is presented here, allowing us to
determine approximately the mass and orbital parameters of the second
companion. Remarkably, the current best-fit parameters correspond to a second
companion of **planetary mass**, with m2 ~0.007 Msun, in an orbit of
eccentricity e2 ~0.45 and with a large semimajor axis a2 ~60 AU. The short
dynamical lifetime of this very wide triple in M4 suggests that large numbers
of such planets must be present in globular clusters. We also address the
question of the anomalously high eccentricity of the inner binary pulsar. While
this eccentricity could have been induced during the same dynamical interaction
that created the triple, we find that it could also naturally arise from
long-term secular perturbation effects in the triple, combining the general
relativistic precession of the inner orbit with the Newtonian gravitational
perturbation by the outer planet.

</DOC>
<DOC>
<DOCNO> 69604 </DOCNO>
Prompt Photon Production in Polarized Hadron Collisions


  We consider spin asymmetries for prompt photon production in collisions of
longitudinally polarized hadrons. This reaction will be a key tool at the
BNL-RHIC pp collider for determining the gluon spin density in a polarized
proton. We study the effects of QCD corrections, such as all-order soft-gluon
`threshold' resummations.

</DOC>
<DOC>
<DOCNO> 118782 </DOCNO>
RJK Observations of the Optical Afterglow of GRB 991216


  We present near-infrared and optical observations of the afterglow to the
Gamma-Ray Burst (GRB) 991216 obtained with the F. L. Whipple Observatory 1.2-m
telescope and the University of Hawaii 2.2-m telescope. The observations range
from 15 hours to 3.8 days after the burst. The temporal behavior of the data is
well described by a single power-law decay with index -1.36 +/-0.04,
independent of wavelength. The optical spectral energy distribution, corrected
for significant Galactic reddening of E(B-V)=0.626, is well fitted by a single
power-law with index -0.58 +/- 0.08. Combining the IR/optical observations with
a Chandra X-ray measurement gives a spectral index of -0.8 +/- 0.1 in the
synchrotron cooling regime. A comparison between the spectral and temporal
power-law indices suggest that a jet is a better match to the observations than
a simple spherical shock.

</DOC>
<DOC>
<DOCNO> 70972 </DOCNO>
Scalar Field Dynamics: Classical, Quantum and in Between


  Using a Hartree ensemble approximation, we investigate the dynamics of the
\f^4 model in 1+1 dimensions. We find that the fields initially thermalize with
a Bose-Einstein distribution for the fields. Gradually, however, the
distribution changes towards classical equipartition. Using suitable initial
conditions quantum thermalization is achieved much faster than the onset of
this undesirable equipartition. We also show how the numerical efficiency of
our method can be significantly improved.

</DOC>
<DOC>
<DOCNO> 40600 </DOCNO>
CP Violation and Mixing Results from FNAL E791


  We review results from FNAL E791 concerning D0-D0bar mixing and CP violation
in D meson decays. We have searched for mixing in semileptonic D0 ->
K+\ell-\bar{\nu} decays and in hadronic D0 -> K+\pi- and D0 -> K+\pi-\pi+\pi-
decays. We have searched for CP violation in D0 -> K+K- / \pi+\pi- and D+ ->
\phi\pi+ / \bar{K}^{*0}K+ / K+K-\pi+ / \pi+\pi-\pi+ decays. Finally, we have
measured the difference in decay widths \Delta\Gamma between the two
mass-eigenstates of the D0-D0bar system. This parameter affects the rate of
D0-D0bar mixing. We combine our results with those from other experiments to
obtain confidence intervals incorporating all published experimental data.

</DOC>
<DOC>
<DOCNO> 101152 </DOCNO>
On automorphisms of arithmetic subgroups of unipotent groups in positive


  Let F be a local field of positive characteristic, and let G be either a
Heisenberg group over F, or a certain (nonabelian) two-dimensional unipotent
group over F. If H is an arithmetic subgroup of G, we provide an explicit
description of every automorphism of H. From this description, it follows that
every automorphism of H virtually extends to a virtual automorphism of G.

</DOC>
<DOC>
<DOCNO> 170080 </DOCNO>
A Bell's Inequality Test with Entangled Atoms


  Previous work on Bell's inequality realised in the laboratory has used
entangled photons. Here we describe how entangled atoms can violate Bell's
inequality, and how these violations can be measured with a very high detection
efficiency. We first discuss a simple scheme based on two-level atoms inside a
cavity to prepare the entangled state. We then discuss a scheme using
four-level atoms, which requires a parameter regime much easier to access
experimentally using current technology. As opposed to other schemes, our
proposal relies on the presence of finite decay rates and its implementation
should therefore be much less demanding.

</DOC>
<DOC>
<DOCNO> 100908 </DOCNO>
The Projective Theory of Ruled Surfaces


  The aim of this paper is to get some results about ruled surfaces which
configure a projective theory of scrolls and ruled surfaces. Our ideas follow
the viewpoint of Corrado Segre, but we employ the contemporaneous language of
locally free sheaves. The results complete the exposition given by R.
Hartshorne and they have not appeared before in the contemporaneous literature.

</DOC>
<DOC>
<DOCNO> 71368 </DOCNO>
The Dual Higgs Mechanism and the Origin of Mass in the Universe


  The idea that a background of invisible material pervades the whole universe
is as old as the history of natural philosophy. Modern particle physics and
cosmology support that idea and identify in the cosmic vacuum the ultimate
source of matter-energy, both seen and unseen, in the universe. In the
framework of the inflation-axion scenario, we suggest an unusual realization of
the Higgs mechanism which converts the latent energy of the vacuum into
observable mass. The existence of a new spontaneously broken symmetry is
pointed out which has the same effect of the Peccei-Quinn symmetry in creating
axions as pseudo-Goldstone bosons. However such particles are eliminated from
the physical spectrum in favor of massive pseudoscalar particles.

</DOC>
<DOC>
<DOCNO> 83276 </DOCNO>
Multicast-based Architecture for IP Mobility: Simulation Analysis and


  With the introduction of a newer generation of wireless devices and
technologies, the need for an efficient architecture for IP mobility is
becoming more apparent. Several architectures have been proposed to support IP
mobility. Most studies, however, show that current architectures, in general,
fall short from satisfying the performance requirements for wireless
applications, mainly audio. Other studies have shown performance improvement by
using multicast to reduce latency and packet loss during handoff. In this
study, we propose a multicast-based architecture to support IP mobility. We
evaluate our approach through simulation, and we compare it to mainstream
approaches for IP mobility, mainly, the Mobile IP protocol. Comparison is
performed according to the required performance criteria, such as smooth
handoff and efficient routing.
  Our simulation results show significant improvement for the proposed
architecture. On average, basic Mobile IP consumes almost twice as much network
bandwidth, and experiences more than twice as much end-to-end and handoff
delays, as does our proposed architecture. Furthermore, we propose an extension
to Mobile IP to support our architecture with minimal modification.

</DOC>
<DOC>
<DOCNO> 99692 </DOCNO>
Cobordism of immersions of surfaces in non-orientable 3-manifolds


  Some properties of non-orientable 3-manifolds are shown. The semi-group of
cobordism of immersions of surfaces in such manifolds is computed and proven
actually to be a group. Explicit invariants are provided.

</DOC>
<DOC>
<DOCNO> 13876 </DOCNO>
Monte Carlo Study of Ferromagnetism in (III,Mn)V Semiconductors


  We report on Monte Carlo studies of the kinetic exchange model for (III,Mn)V
ferromagnetic semiconductors in which S=5/2 local moments, representing Mn^{2+}
ions, are exchange coupled to band electrons. We treat the Mn^{2+}$ spin
orientations as classical degrees of freedom and use the Hybrid Monte Carlo
algorithm to explore thermodynamically important Mn spin configurations. The
critical temperature T_c of the model is unambiguously signalled in our
finite-size simulations by pronounced peaks in fluctuations of both Mn and band
carrier total spins. The T_c's we obtain are, over much of the model's
parameter space, substantially smaller than those estimated using mean-field
theory. When mean-field theory fails, short-range magnetic order and finite
{\em local} carrier spin polarisation are present for temperatures
substantially larger than T_{c}. For the simplest version of the model, which
has a single parabolic band with effective mass m^*, the dependence of T_{c} on
m^* is sublinear at large masses, in disagreement with the mean-field theory
result T_{c} \propto m^*. For the carrier densities studied, results obtained
with a six-band Luttinger model band Hamiltonian are in good agreement with
those obtained for a model with a single parabolic band whose effective mass is
equal to the Kohn-Luttinger model heavy-hole mass.

</DOC>
<DOC>
<DOCNO> 119233 </DOCNO>
Disc heating in NGC 2985


  Various processes have been proposed to explain how galaxy discs acquire
their thickness. A simple diagnostic for ascertaining this ``heating''
mechanism is provided by the ratio of the vertical to radial velocity
dispersion components. In a previous paper we have developed a technique for
measuring this ratio, and demonstrated its viability on the Sb system NGC 488.
Here we present follow-up observations of the morphologically similar Sab
galaxy NGC 2985, still only the second galaxy for which this ratio has been
determined outside of the solar neighbourhood. The result is consistent with
simple disc heating models which predict ratios of $\sigma_z / \sigma_R$ less
than one

</DOC>
<DOC>
<DOCNO> 118330 </DOCNO>
Neural networks and separation of Cosmic Microwave Background and


  The Independent Component Analysis (ICA) algorithm is implemented as a neural
network for separating signals of different origin in astrophysical sky maps.
Due to its self-organizing capability, it works without prior assumptions on
the signals, neither on their frequency scaling, nor on the signal maps
themselves; instead, it learns directly from the input data how to separate the
physical components, making use of their statistical independence. To test the
capabilities of this approach, we apply the ICA algorithm on sky patches, taken
from simulations and observations, at the microwave frequencies, that are going
to be deeply explored in a few years on the whole sky, by the Microwave
Anisotropy Probe (MAP) and by the {\sc Planck} Surveyor Satellite. The maps are
at the frequencies of the Low Frequency Instrument (LFI) aboard the {\sc
Planck} satellite (30, 44, 70 and 100 GHz), and contain simulated astrophysical
radio sources, Cosmic Microwave Background (CMB) radiation, and Galactic
diffuse emissions from thermal dust and synchrotron. We show that the ICA
algorithm is able to recover each signal, with precision going from 10% for the
Galactic components to percent for CMB; radio sources are almost completely
recovered down to a flux limit corresponding to $0.7\sigma_{CMB}$, where
$\sigma_{CMB}$ is the rms level of CMB fluctuations. The signal recovering
possesses equal quality on all the scales larger then the pixel size. In
addition, we show that the frequency scalings of the input signals can be
partially inferred from the ICA outputs, at the percent precision for the
dominant components, radio sources and CMB.

</DOC>
<DOC>
<DOCNO> 170575 </DOCNO>
An extension of "Popper's experiment" can test interpretations of


  Karl Popper proposed a way to test whether a proposed relation of a
quantum-mechanical state to perceived reality in the Copenhagen interpretation
(CI) of quantum mechanics - namely that the state of a particle is merely an
expression of ``what is known'' about the system - is in agreement with all
experimental facts. A conceptual flaw in Popper's proposal is identified and an
improved version of his experiment (called ``Extension step 1'') - which fully
serves its original purpose - is suggested. The main purpose of this paper is
to suggest to perform this experiment. The results of this experiment predicted
under the alternative assumptions that the CI - together with the above
connection of the state function with reality - or the ``many-worlds''
interpretation (MWI) is correct are shown to be identical. Only after a further
modification (called ``Extension step 2'') - the use of an ion isolated from
the macroscopic environment as particle detector - the predictions using the
respective interpretations become qualitatively different.

</DOC>
<DOC>
<DOCNO> 11800 </DOCNO>
Exact Eignstates for Trapped Weakly Interacting Bosons in Two Dimensions


  A system of N two-dimensional weakly interacting bosons in a harmonic trap is
considered. When the two-particle potential is a delta function Smith and
Wilkin have analytically proved that the elementary symmetric polynomials of
particle coordinates measured from the center of mass are exact eigenstates. In
this study, we point out that their proof works equally well for an arbitrary
two-particle potential which possesses the translational and rotational
symmetries. We find that the interaction energy associated with the eigenstate
with angular momentum L is equal to aN(N-1)/2+(b-a)NL/2, where a and b are the
interaction energies of two bosons in the lowest-energy one-particle state with
zero and one unit of angular momentum, respectively. Additionally, we study
briefly the case of attractive quartic interactions. We prove rigorously that
the lowest-energy state is the one in which all angular momentum is carried by
the center of mass motion.

</DOC>
<DOC>
<DOCNO> 40424 </DOCNO>
The Structure of the Virtual Photon


  Measurements of dijet cross sections for virtual photons are presented as a
function of $\xo$, the fraction of the virtual photon energy invested in the
production of the dijet system, using the ZEUS detector. Comparisons to QCD
predictions show that a resolved photon component is needed to describe the
data up to values of the photon virtuality comparable to the scale of the
interaction.

</DOC>
<DOC>
<DOCNO> 117093 </DOCNO>
Transport control by coherent zonal flows in the core/edge transitional


  3D Braginskii turbulence simulations show that the energy flux in the
core/edge transition region of a tokamak is strongly modulated - locally and on
average - by radially propagating, nearly coherent sinusoidal or solitary zonal
flows. The flows are geodesic acoustic modes (GAM), which are primarily driven
by the Stringer-Winsor term. The flow amplitude together with the average
anomalous transport sensitively depend on the GAM frequency and on the magnetic
curvature acting on the flows, which could be influenced in a real tokamak,
e.g., by shaping the plasma cross section. The local modulation of the
turbulence by the flows and the excitation of the flows are due to wave-kinetic
effects, which have been studied for the first time in a turbulence simulation.

</DOC>
<DOC>
<DOCNO> 7718 </DOCNO>
Different approaches in the theory of the metastable phase decay on


  The situation of the metastable phase decay on the several types of
heterogeneous centers is considered. The iteration procedure is formulated and
with the help of the avalanche consumption property all iterations can be
calculated. The same procedure is done for the monodisperse approximation. Here
the avalnche consumption is also used to calculate iterations. It is shown that
all iterations with a high number have one and the same structure. It allows to
obtain the functional form of solution and to formulate directly an equation on
the parameter of this functional form.

</DOC>
<DOC>
<DOCNO> 102362 </DOCNO>
The approach of St"ohr-Voloch to the Hasse-Weil bound with applications


  This is an expository paper concerning topics on rational points of curves
defined over finite fields based on a paper by St"ohr and Voloch.

</DOC>
<DOC>
<DOCNO> 12895 </DOCNO>
Magnon-assisted Andreev reflection in a ferromagnet-superconductor


  We study subgap transport in a ferromagnet-superconductor junction at low
temperature due to Andreev reflection. The mismatch of spin polarized current
in the ferromagnet and spinless current in the superconductor results in an
additional contact resistance which can be reduced by magnon emission in the
ferromagnet. Using the s-f model and focusing on half-metallic ferromagnets, we
calculate the corresponding nonlinear contribution to the current which is
asymmetric with respect to the sign of the bias voltage and is related to the
density of states of magnons in the ferromagnet.

</DOC>
<DOC>
<DOCNO> 12291 </DOCNO>
Quantum computing of quantum chaos and imperfection effects


  We study numerically the imperfection effects in the quantum computing of the
kicked rotator model in the regime of quantum chaos. It is shown that there are
two types of physical characteristics: for one of them the quantum computation
errors grow exponentially with the number of qubits in the computer while for
the other the growth is polynomial. Certain similarity between classical and
quantum computing errors is also discussed.

</DOC>
<DOC>
<DOCNO> 68031 </DOCNO>
The static quark potential in three flavor QCD


  We study the effects of dynamical quarks on the static quark potential at
distances shorter than those where string breaking is expected. Quenched
calculations and calculations with three flavors of dynamical quarks are done
on sets of lattices with the lattice spacings matched within about one percent.
The effect of the sea quarks on the shape of the potential is clearly visible.
We investigate the consequences of these effects in a very crude model, namely
solving Schroedinger's equation in the resulting potential.

</DOC>
<DOC>
<DOCNO> 9280 </DOCNO>
Exact and numerical results for the dimerized spin-orbital model


  We establish exact results for the one-dimensional spin-orbital model for
special values of the four-spin interaction $V$ and dimerization parameter
$\delta$. The first exact result is at $\delta=1/2$ and $V=-2$. Because we find
a very small but finite gap in this dimerized chain, this can serve as a very
strong test case for numerical and approximate analytical techniques. The
second result is for the homogeneous chain with $V=-4$ and gives evidence that
the system has a spontaneously dimerized ground state. Numerical results
indicate that the interplay between dimerization and interaction could result
in gapless phases in the regime $0\leq V<-2$.

</DOC>
<DOC>
<DOCNO> 8961 </DOCNO>
On the metallic behaviour in dilute two-dimensional systems


  We have studied the metallic behaviour in low density GaAs hole systems, and
Si electron systems, close to the apparent two-dimensional metal-insulator
transition. Two observations suggest a semi-classical origin for the
metallic-like behaviour. Firstly the strength of the metallic behaviour is
almost independent of the symmetry of the confining potential, and is
predominantly determined by the low temperature resistivity (i.e. by k_F*l).
Secondly the fractional decrease in conductivity with increasing temperature
depends only on T/T_F, independent of the carrier density, in both systems.

</DOC>
<DOC>
<DOCNO> 101264 </DOCNO>
The bilinear maximal functions map into L^p for 2/3 < p <= 1


  The bilinear maximal operator defined below maps $L^p\times L^q$ into $L^r$
provided $1<p,q<\zI$, $1/p+1/q=1/r$ and $2/3<r\le1$. $$
Mfg(x)=\sup_{t>0}\frac1{2t}\int_{-t}^t\abs{f(x+y)g(x-y)} dy.$$ In particular
$Mfg$ is integrable\thinspace if $f$ and $g$ are square integrable, answering a
conjecture posed by Alberto Calder\'on.

</DOC>
<DOC>
<DOCNO> 69315 </DOCNO>
Cosmic ray signatures of massive relic particles


  The possibility that the Fermi scale is the only fundamental energy scale of
Nature is under serious consideration at present, yet cosmic rays may already
have provided direct evidence of new physics at a much higher scale. The recent
detection of very high energy particles with no plausible astrophysical sources
suggests that these originate from the slow decays of massive particles
clustered in the halo of our Galaxy. Such particles had in fact been predicted
to exist beforehand with mass and lifetime in the range required to explain the
observations. I discuss recent work focussing on experimental tests of this
speculative but exciting idea.

</DOC>
<DOC>
<DOCNO> 122788 </DOCNO>
Photometric and Spectroscopic Analysis of Cool White Dwarfs with


  A photometric and spectroscopic analysis of 152 cool white dwarf stars is
presented. The discovery of 7 new DA white dwarfs, 2 new DQ white dwarfs, 1 new
magnetic white dwarf, and 3 weak magnetic white dwarf candidates, is reported,
as well as 19 known or suspected double degenerates. The photometric energy
distributions, the Halpha line profiles, and the trigonometric parallax
measurements are combined and compared to model atmosphere calculations to
determine the effective temperature and the radius of each object, and also to
constrain the atmospheric composition. New evolutionary sequences with C/O
cores with thin and thick hydrogen layers are used to derive masses and ages.
We confirm the existence of a range in Teff between 5000 and 6000K where almost
all white dwarfs have H-rich atmospheres. There is little evidence for mixed
H/He dwarfs, with the exception of 2 He-rich DA stars, and 5 C2H white dwarfs
which possibly have mixed H/He/C atmospheres. The DQ sequence terminates near
6500K, below which they are believed to turn into C2H stars. True DC stars
slightly above this temperature are found to exhibit H-like energy
distributions despite the lack of Halpha absorption. Attempts to interpret the
chemical evolution show the problem to be complex. Convective mixing is
necessary to account for the non-DA to DA ratio as a function of temperature.
The presence of helium in cool DA stars, the existence of the non-DA gap, and
the peculiar DC stars are also explained in terms of convective mixing,
although our understanding of how this mechanism works needs to be revised. The
oldest object in our sample is about 7.9 Gyr or 9.7 Gyr old depending on
whether thin or thick hydrogen layer models are used. The mean mass of our
sample is 0.65 +/- 0.20 Msun.

</DOC>
<DOC>
<DOCNO> 150434 </DOCNO>
Orbifold projection in supersymmetric QCD at N_f\leq N_c


  Supersymmetric orbifold projection of N=1 SQCD with relatively small number
of flavors (not larger than the number of colors) is considered. The purpose is
to check whether orbifolding commutes with the infrared limit. On the one hand,
one considers the orbifold projection of SQCD and obtains the low-energy
description of the resulting theory. On the other hand, one starts with the
low-energy effective theory of the original SQCD, and only then perfoms
orbifolding. It is shown that at finite N_c the two low-energy theories
obtained in these ways are different. However, in the case of stabilized
run-away vacuum these two theories are shown to coincide in the large N_c
limit. In the case of quantum modified moduli space, topological solitons
carrying baryonic charges are present in the orbifolded low-energy theory.
These solitons may restore the correspondence between the two theories provided
that the soliton mass tends to zero in the large N_c limit.

</DOC>
<DOC>
<DOCNO> 170275 </DOCNO>
Generalization of Grover's Algorithm to Multiobject Search in Quantum


  L. K. Grover's search algorithm in quantum computing gives an optimal,
quadratic speedup in the search for a single object in a large unsorted
database. In this paper, we generalize Grover's algorithm in a Hilbert-space
framework for both continuous and discrete time cases that isolates its
geometrical essence to the case where more than one object satisfies the search
criterion.

</DOC>
<DOC>
<DOCNO> 84520 </DOCNO>
On the equations of motion of point-particle binaries at the third


  We investigate the dynamics of two point-like particles through the third
post-Newtonian (3PN) approximation of general relativity. The infinite
self-field of each point-mass is regularized by means of Hadamard's concept of
``partie finie''. Distributional forms associated with the regularization are
used systematically in the computation. We determine the stress-energy tensor
of point-like particles compatible with the previous regularization. The
Einstein field equations in harmonic coordinates are iterated to the 3PN order.
The 3PN equations of motion are Lorentz-invariant and admit a conserved energy
(neglecting the 2.5PN radiation reaction). They depend on an undetermined
coefficient, in agreement with an earlier result of Jaranowski and Schaefer.
This suggests an incompleteness of the formalism (in this stage of development)
at the 3PN order. In this paper we present the equations of motion in the
center-of-mass frame and in the case of circular orbits.

</DOC>
<DOC>
<DOCNO> 151661 </DOCNO>
Differential equations for general SU(n) Bethe ansatz systems


  We show that SU(n) Bethe Ansatz equations with arbitrary `twist' parameters
are hidden inside certain nth order ordinary differential equations, and
discuss various consequences of this fact.

</DOC>
<DOC>
<DOCNO> 100228 </DOCNO>
The variational principle for a class of asymptotically abelian


  Let (A,\alpha) be a C*-dynamical system. We introduce the notion of pressure
P_\alpha(H) of the automorphism \alpha at a self-adjoint operator H\in A. Then
we consider the class of AF-systems satisfying the following condition: there
exists a dense \alpha-invariant *-subalgebra \A of A such that for all pairs
a,b\in\A the C*-algebra they generate is finite dimensional, and there is
p=p(a,b)\in\N such that [\alpha^j(a),b]=0 for |j|\ge p. For systems in this
class we prove the variational principle, i.e. show that P_\alpha(H) is the
supremum of the quantities h_\phi(\alpha)-\phi(H), where h_\phi(\alpha) is the
Connes-Narnhofer-Thirring dynamical entropy of \alpha with respect to the
\alpha-invariant state \phi. If H\in\A, and P_\alpha(H) is finite, we show that
any state on which the supremum is attained is a KMS-state with respect to a
one-parameter automorphism group naturally associated with H. In particular,
Voiculescu's topological entropy is equal to the supremum of h_\phi(\alpha),
and any state of finite maximal entropy is a trace.

</DOC>
<DOC>
<DOCNO> 152309 </DOCNO>
String Theory Origins of Supersymmetry


  The string theory introduced in early 1971 by Ramond, Neveu, and myself has
two-dimensional world-sheet supersymmetry. This theory, developed at about the
same time that Golfand and Likhtman constructed the four-dimensional
super-Poincar\'e algebra, motivated Wess and Zumino to construct supersymmetric
field theories in four dimensions. Gliozzi, Scherk, and Olive conjectured the
spacetime supersymmetry of the string theory in 1976, a fact that was proved
five years later by Green and myself.

</DOC>
<DOC>
<DOCNO> 101989 </DOCNO>
Tight contact structures and taut foliations


  We show the equivalence of several notions in the theory of taut foliations
and the theory of tight contact structures. We prove equivalence, in certain
cases, of existence of tight contact structures and taut foliations.

</DOC>
<DOC>
<DOCNO> 99275 </DOCNO>
A remark on circular means of Fourier transforms of measures


  In a recent paper of Wolff the optimal decay of circular L^p means of
compactly supported measures of finite energy was given for p>=2, with
application to Falconer's distance problem. The question was then raised in
that paper as to whether any non-trivial improvement to these estimates were
available for p < 2. We answer this question in the negative.

</DOC>
<DOC>
<DOCNO> 118215 </DOCNO>
Cosmic Star Formation History Required from Infrared Galaxy Number Count


  We constructed a model of infrared and sub-mm (hereafter IR) galaxy number
count and estimated history of the IR luminosity density. We treat the
evolutionary change of galaxy luminosities as a stepwise nonparametric form, in
order to explore the most suitable evolutionary history which reproduces the
present observational results. We found the evolutionary patterns which satisfy
both constraints required from Cosmic Infrared Background (CIRB) and IR galaxy
number counts. One order of magnitude increase of luminosity at redshift
$z=0.75 - 1.0$ was found in IR $60 \mu$m luminosity density evolution. We also
found that a large number of galaxies ($\sim 10^7$ in the whole sky) will be
detected in all-sky survey at far-infrared by Infrared Imaging Surveyor (IRIS);
Japanese infrared satellite project Astro-F.

</DOC>
<DOC>
<DOCNO> 69582 </DOCNO>
The Future of Particle Physics


  After a very brief review of twentieth century elementary particle physics,
prospects for the next century are discussed. First and most important are
technological limits of opportunities; next, the future experimental program,
and finally the status of the theory, in particular its limitations as well as
its opportunities.

</DOC>
<DOC>
<DOCNO> 68362 </DOCNO>
New constraints for non-Newtonian gravity in nanometer range from the


  We obtain constraints on non-Newtonian gravity following from the improved
precision measurement of the Casimir force by means of atomic force microscope.
The hypothetical force is calculated in experimental configuration (a sphere
above a disk both covered by two metallic layers). The strengthenings of
constraints up to 4 times comparing the previous experiment and up to 560 times
comparing the Casimir force measurements between dielectrics are obtained in
the interaction range 5.9 nm$\leq\lambda\leq 115 $nm. Recent speculations about
the presence of some unexplained attractive force in the considered experiment
are shown to be unjustified.

</DOC>
<DOC>
<DOCNO> 8475 </DOCNO>
Shape and Motion of Vortex Cores in Bi_2Sr_2CaCu_2O_{8+\delta}


  We present a detailed study on the behaviour of vortex cores in
Bi_2Sr_2CaCu_2O_{8+\delta} using scanning tunneling spectroscopy. The very
irregular distribution and shape of the vortex cores imply a strong pinning of
the vortices by defects and inhomogeneities. The observed vortex cores seem to
consist of two or more randomly distributed smaller elements. Even more
striking is the observation of vortex motion where the vortex cores are divided
between two positions before totally moving from one position to the other.
Both effects can be explained by quantum tunneling of vortices between
different pinning centers.

</DOC>
<DOC>
<DOCNO> 71271 </DOCNO>
Anomaly-Free Flavor Symmetry and Neutrino Anarchy


  We show that one can describe the quark and lepton masses with a single
anomaly-free U(1) flavor symmetry provided a single order one parameter is
enhanced by roughly 4-5. The flavor symmetry can be seen to arise from inside
the $E_6$ symmetry group in such a way that it commutes with the SU(5) grand
unified gauge group. The scenario does not distinguish between the left-handed
lepton doublets and hence is a model of neutrino anarchy. It can therefore
account for the large mixing observed in atmospheric neutrino experiments and
predicts that the solar neutrino oscillation data is consistent with the large
mixing angle solution of matter-enhanced oscillations.

</DOC>
<DOC>
<DOCNO> 68074 </DOCNO>
Radical Conservatism and Nucleon Decay


  Unification of couplings, observation of neutrino masses in the expected
range, and several other considerations confirm central implications of
straightforward gauge unification based on SO(10) or a close relative and
incorporating low-energy supersymmetry. The remaining outstanding consequence
of this circle of ideas, yet to be observed, is nucleon instability. Clearly,
we should aspire to be as specific as possible regarding the rate and form of
such instability. I argue that not only esthetics, but also the observed
precision of unification of couplings, favors an economical symmetry-breaking
(Higgs) structure. Assuming this, one can exploit its constraints to build
reasonably economical, overconstrained yet phenomenologically viable models of
quark and lepton masses. Putting it all together, one arrives at reasonably
concrete, hopeful expectations regarding nucleon decay. These expectations are
neither ruled out by existing experiments, nor hopelessly inaccessible.

</DOC>
<DOC>
<DOCNO> 117991 </DOCNO>
The Impact of Rotation on Cluster Dynamics


  The evolution of rotating, isolated clusters of stars up to core-collapse is
investigated with n-body numerical codes. The simulations start off from
axisymmetric generalisations of King profiles, with added global angular
momentum. In this contribution I report on results obtained for two sets of
single-mass cluster simulations. These confirm the more rapid evolution of even
mildly-rotating clusters. A model is presented with rotational energy
comparable to omega-Centauri's; it reaches core-collapse in less than half the
time required for non-rotating model clusters.

</DOC>
<DOC>
<DOCNO> 102160 </DOCNO>
The strict order property and generic automorphisms


  If T is an model complete theory with the strict order property, then the
theory of the models of T with an automorphism has no model companion.

</DOC>
<DOC>
<DOCNO> 120935 </DOCNO>
A New Angle on Gravitational Clustering


  We describe a new approach to gravitational instability in large-scale
structure, where the equations of motion are written and solved as in field
theory in terms of Feynman diagrams. The basic objects of interest are the
propagator (which propagates solutions forward in time), the vertex (which
describes non-linear interactions between waves) and a source with prescribed
statistics which describes the effect of initial conditions. We show that loop
corrections renormalize these quantities, and discuss applications of this
formalism to a better understanding of gravitational instability and to
improving non-linear perturbation theory in the transition to the non-linear
regime. We also consider the role of vorticity creation due to shell-crossing
and show using N-body simulations that at small (virialized) scales the
velocity field reaches equipartition, i.e. the vorticity power spectrum is
about twice the divergence power spectrum.

</DOC>
<DOC>
<DOCNO> 121884 </DOCNO>
Searching for high-z field ellipticals: successes and problems


  The most recent observational results on the search for high redshift field
ellipticals are reviewed in the context of galaxy formation scenarios. The
perspectives for Large Binocular Telescope (LBT) observations are also
discussed.

</DOC>
<DOC>
<DOCNO> 152002 </DOCNO>
Deforming Einstein's Gravity


  A deformation of Einstein Gravity is constructed based on gauging the
noncommutative ISO(3,1) group using the Seiberg-Witten map. The transformation
of the star product under diffeomorphism is given, and the action is determined
to second order in the deformation parameter.

</DOC>
<DOC>
<DOCNO> 178489 </DOCNO>
Quantum interference in the e^+e^- decays of rho^0 and omega-mesons


  The study of the pi^- p -> rho^0 n and pi^- p -> omega n amplitudes close and
below the vector meson production threshold (1.2< sqrt(s) <1.8 GeV) reveals a
rich dynamics arising from the presence of specific baryon resonances in this
energy range. The interference pattern of the e^+e^- decays of the rho^0 and
omega mesons produced in pi^- p reactions reflects directly this dynamics. We
discuss this interference pattern in the pi^- p -> e^+e^- n reaction as
function of the total center of mass energy sqrt(s). We emphasize the
importance of an experimental study of this reaction, which could be made with
the HADES detector and the available pion beam at GSI.

</DOC>
<DOC>
<DOCNO> 7696 </DOCNO>
Debye screening and Meissner effect in a two-flavor color superconductor


  I compute the gluon self-energy in a color superconductor with two flavors of
massless quarks, where condensation of Cooper pairs breaks SU(3)_c to SU(2)_c.
At zero temperature, there is neither Debye screening nor a Meissner effect for
the three gluons of the unbroken SU(2)_c subgroup. The remaining five gluons
attain an electric as well as a magnetic mass. For temperatures approaching the
critical temperature for the onset of color superconductivity, or for gluon
momenta much larger than the color-superconducting gap, the self-energy assumes
the form given by the standard hard-dense loop approximation. The gluon
self-energy determines the coefficient of the kinetic term in the effective
low-energy theory for the condensate fields.

</DOC>
<DOC>
<DOCNO> 8430 </DOCNO>
Pulse driven switching in one-dimensional nonlinear photonic band gap


  We examine numerically the time-dependent properties of nonlinear bistable
multilayer structures for constant wave illumination. We find that our system
exhibits both steady-state and self-pulsing solutions. In the steady state
regime, we examine the dynamics of driving the system between different
transmission states by injecting pulses, and we find the optimal pulse
parameters. We repeat this work for the case of a linear periodic system with a
nonlinear impurity layer.

</DOC>
<DOC>
<DOCNO> 169902 </DOCNO>
Persistent entanglement in arrays of interacting particles


  We study the entanglement properties of a class of $N$ qubit quantum states
that are generated in arrays of qubits with an Ising-type interaction. These
states contain a large amount of entanglement as given by their Schmidt
measure. They have also a high {\em persistency of entanglement} which means
that $\sim N/2$ qubits have to be measured to disentangle the state. These
states can be regarded as an entanglement resource since one can generate a
family of other multi-particle entangled states such as the generalized GHZ
states of $<N/2$ qubits by simple measurements and classical communication
(LOCC).

</DOC>
<DOC>
<DOCNO> 84276 </DOCNO>
Cauchy-characteristic matching for a family of cylindrical vacuum


  This paper is part of a long term program to Cauchy-characteristic matching
(CCM) codes as investigative tools in numerical relativity. The approach has
two distinct features: (i) it dispenses with an outer boundary condition and
replaces this with matching conditions at an interface between the Cauchy and
characteristic regions, and (ii) by employing a compactified coordinate, it
proves possible to generate global solutions. In this paper CCM is applied to
an exact two-parameter family of cylindrically symmetric vacuum solutions
possessing both gravitational degrees of freedom due to Piran, Safier and Katz.
This requires a modification of the previously constructed CCM cylindrical code
because, even after using Geroch decomposition to factor out the $z$-direction,
the family is not asymptotically flat. The key equations in the characteristic
regime turn out to be regular singular in nature.

</DOC>
<DOC>
<DOCNO> 102799 </DOCNO>
Toric degenerations of Schubert varieties


  Let $G$ be a simply connected semi-simple complex algebraic group. Fix a
maximal torus $T$ and a Borel subgroup $B$ such that $T\subset B\subset G$. Let
$W$ the Weyl group of $G$ relative to $T$. For any $w$ in $W$, let $X_w=\bar
{BwB/B}$ denote the Schubert variety corresponding to $w$. This talk is
concerned with the following problem : Is there a flat family over Spec${\bf
C}[t]$, such that the general fiber is $X_w$ and the special fiber is a toric
variety? Our approach of the problem is based on the canonical/global base of
Lusztig/Kashiwara and the so-called string parametrization of this base studied
by P. Littelmann and made precise by A. Berenstein and A. Zelevinsky. Fix $w$
in $W$ and let $P^+$ be the semigroup of dominant weights. For all $\lambda$ in
$P^+$, let ${\cal L}_\lambda$ be the line bundle on $G/B$ corresponding to
$\lambda$. Then, the direct sum of global sections $R_w:=\bigoplus_{\lambda\in
P^+}H^0(X_w,{\cal L}_\lambda)$ carries a natural structure of $P^+$-graded
${\bf C}$-algebra. Moreover, there exists a natural action of $T$ on $R_w$. Our
principal result can be stated as follows : There exists a filtration $({\cal
F}_m^w)_{m\in{\bf N}}$ of $R_w$ such that (i) for all $m$ in ${\bf N}$, ${\cal
F}_m^w$ is compatible with the $P^+$-grading of $R_w$, (ii) for all $m$ in
${\bf N}$, ${\cal F}_m^w$ is compatible with the action of $T$, (iii) the
associated graded algebra is the ${\bf C}$-algebra of the semigroup of integral
points in a rational convex polyhedral cone. Equations for this cone were
obtained by A. Berenstein and A. Zelevinski from $\tilde w_0$-trails in
fundamental Weyl modules of the Langlands dual of $G$. By standard arguments,
the previous theorem gives a positive answer to the Degeneration Problem.

</DOC>
<DOC>
<DOCNO> 13478 </DOCNO>
Electronic pressure on ferromagnetic domain wall


  The scattering of the eletron by a domain wall in a nano-wire is studied
perturbatively to the lowest order. The correction to the thermodaynamic
potential of the electron system due to the scattering is calculated from the
phase shift. The wall profile is determined by taking account of this
correction, and the result indicates that the wall in a ferromagnet with small
exchange coupling can be squeezed to be very thin to lower the electron energy.

</DOC>
<DOC>
<DOCNO> 12302 </DOCNO>
A Family of Grover's Quantum Searching Algorithms


  We introduce the concepts of Grover operators and Grover kernels to
systematically analyse Grover's searching algorithms. Then, we investigate a
one-parameter family of quantum searching algorithms of Grover's type and we
show that the standard Grover's algorithm is a distinguished member of this
family. We show that all the algorithms of this class solve the searching
problem with an efficiency of order $O(\sqrt{N})$, with a coefficient which is
class-dependent. The analysis of this dependence is a test of the stability and
robustness of the algorithms. We show the stability of this constructions under
perturbations of the initial conditions and extend them upon a very general
class of Grover operators.

</DOC>
<DOC>
<DOCNO> 123246 </DOCNO>
Searches for Rare and New Types of Objects


  Systematic exploration of the observable parameter space, covered by large
digital sky surveys spanning a range of wavelengths, will be one of the primary
modes of research with a Virtual Observatory (VO). This will include searches
for rare, unusual, or even previously unknown types of astronomical objects and
phenomena, e.g. as outliers in some parameter space of measured properties,
both in the catalog and image domains. Examples from current surveys include
high-redshift quasars, type-2 quasars, brown dwarfs, and a small number of
objects with puzzling spectra. Opening of the time domain will be especially
interesting in this regard. Data-mining tools such as unsupervised clustering
techniques will be essential in this task, and should become an important part
of the VO toolkit.

</DOC>
<DOC>
<DOCNO> 120419 </DOCNO>
An Unusual Burst from Soft Gamma Repeater SGR 1900+14: Comparisons with


  The Soft Gamma Repeater SGR 1900+14 entered a remarkable phase of activity
during the summer of 1998. This activity peaked on August 27, 1998 when a giant
periodic gamma-ray flare resembling the famous March 5, 1979 event from SGR
0526-66 was recorded. Two days later (August 29), a strong, bright burst was
detected with RXTE and BATSE. This event reveals several similarities to the
giant flares of August 27 and March 5, and shows a number of unique features
not previously seen in SGR bursts. Unlike typically short SGR bursts, this
event features a 3.5 s burst peak that was preceded by an extended (~ 1 s)
complex precursor, and followed by a long (~ 1000 s) periodic tail modulated at
the 5.16 s stellar rotation period. Spectral analysis shows a striking
distinction between the spectral behavior of the precursor, burst peak and
extended tail. While the spectrum during the peak is uniform, a significant
spectral evolution is detected in both the precursor and tail emissions.
Temporal behavior shows a sharp rise (~ 9.8 ms) at the event onset and a rapid
cutoff (~ 17 ms) at the end of the burst peak. The tail pulsations show a
simple pulse profile consisting of one 5.16 s peak that did not evolve with
time. The spectral and temporal signatures of this event imply that the
precursor, main peak, and extended tail are produced by different physical
mechanisms. We discuss these features and their implications in the context of
the magnetar model. The energetics of the August 29 event, and its close
proximity to the August 27 flare, suggest that it is an `aftershock' of the
preceding giant flare. "P.S. This is an abbreviated version of the original
abstract."

</DOC>
<DOC>
<DOCNO> 174509 </DOCNO>
The $(\pi^-,\gamma\gamma)$ program at TRIUMF


  We report the first observation of the doubly-radiative decay mode of pionic
hydrogen (pi- p --> gamma gamma n) and and deuterium (pi- d --> gamma gamma X)
using the RMC pair spectrometer at TRIUMF. The process is interesting in the
context of the pi-Compton scattering and the chiPT predictions of the pion
polarizability We present our preliminary values for the B.R.(pi- p --> gamma
gamma n)=3.8x10^-5 and B.R.(pi- d --> gamma gamma X)=1.6x10^-5. Our pi- p data
indicates the dominance of pi pi --> gamma gamma mechanism. The pi- d data
shows no evidence for the d1* dibaryon.

</DOC>
<DOC>
<DOCNO> 101762 </DOCNO>
Quantization of Damped Harmonic Oscillator, Thermal Field Theories and


  We study the canonical quantization of the damped harmonic oscillator by
resorting to the realization of the q-deformation of the Weyl-Heisenberg
algebra (q-WH) in terms of finite difference operators. We relate the damped
oscillator hamiltonian to the q-WH algebra and to the squeezing generator of
coherent states theory. We also show that the q-WH algebra is the natural
candidate to study thermal field theory. The well known splitting, in the
infinite volume limit, of the space of physical states into unitarily
inequivalent representations of the canonical commutation relations is briefly
commented upon in relation with the von Neumann theorem in quantum mechanics
and with q-WH algebra.

</DOC>
<DOC>
<DOCNO> 102148 </DOCNO>
Noncommutative pressure and the variational principle in


  We define a notion of dynamical pressure at a self-adjoint element for a
contractive completely positive self-map of an exact C*-algebra which adopts
Voiculescu's approximation approach to noncommutative entropy and extends the
Voiculescu-Brown topological entropy and Neshveyev-Stormer unital-nuclear
pressure. A variational inequality bounding the pressure below by the free
energies with respect to the Sauvageot-Thouvenot entropy is established in two
stages via the introduction of a local state approximation entropy, whose
associated free energies function as an intermediate term.
   Pimsner C*-algebras furnish a framework for investigating the variational
principle, which asserts the equality of the pressure and the supremum of the
free energies over all dynamically invariant states. In one direction we extend
Brown's result on the constancy of the Voiculescu-Brown entropy upon passing to
the crossed product, and in another we show that the pressure of a self-adjoint
element over the Markov subshift underlying the canonical map on a
Cuntz-Kreiger algebra is equal to its classical pressure. The latter result is
extended to a more general setting comprising an expanded class of
Cuntz-Krieger-type Pimsner algebras, leading to the variational principle for
self-adjoint elements in a diagonal subalgebra. Equilibrium states are
constructed from KMS states under certain conditions in the case of
Cuntz-Krieger algebras.

</DOC>
<DOC>
<DOCNO> 70852 </DOCNO>
Soft QCD Dynamics of Elastic Scattering in Impact Parameter


  The elastic hadronic amplitude is calculated using the nonperturbative
light-cone dipole representation for gluon bremsstrahlung. The data for large
mass diffraction demand a two-scale structure of light hadrons: the gluon
clouds of the valence quarks with a size of 0.3fm and the hadronic size 1fm.
The presence of the two scales unavoidably leads to a specific form for the
total hadronic cross section which consists of a steeply rising \propto
s^{\Delta} (\Delta=0.17 +/- 0.01) term related to gluon radiation, and a large
constant term originating from soft interactions which does not induce any
gluon emission. Our calculations reproduce well the total cross sections and
elastic slopes \cite{k3p}. To further test the model, we analyze the elastic pp
and ppbar differential cross sections and extract the partial amplitudes in the
impact parameter representation. The Pomeron trajectory as a function of the
impact parameter is only slightly above one for central collisions, but steeply
grows towards the periphery. The model predicts correctly the shape and energy
dependence of the partial amplitude at all impact parameters.

</DOC>
<DOC>
<DOCNO> 174462 </DOCNO>
Isospin dependence of isobaric ratio Y(3H)/Y(3He) and its relation to


  A dependence of the isobaric ratio Y(3H)/Y(3He) on the N/Z ratio of the
reconstructed quasiprojectile for the reaction of 28Si beam with 112,124Sn
targets at two different projectile energies 30 and 50 MeV/nucleon is
presented. We demonstrate a linear dependence of ln(Y(3H)/Y(3He)) on the
quasiprojectile N/Z ratio and show the dependence of the slope on reconstructed
excitation energy of the quasiprojectile. We relate this slope dependence at a
given excitation energy to the temperature of the fragmenting system. Using the
model assumptions of the statistical multifragmentation model, a method of
temperature determination is proposed. A caloric curve is constructed and
compared to the result of double isotope ratio method for the same set of data
and to the results of other studies.

</DOC>
<DOC>
<DOCNO> 13016 </DOCNO>
Discrete energy landscapes and replica symmetry breaking at zero


  The order parameter P(q) for disordered systems with degenerate ground-states
is reconsidered. We propose that entropy fluctuations lead to a trivial P(q) at
zero temperature as in the non-degenerate case, even if there are zero-energy
large-scale excitations (complex energy landscape). Such a situation should
arise in the 3-dimensional +-J Ising spin glass and in MAX-SAT. Also, we argue
that if the energy landscape is complex with a finite number of ground-state
families, then replica symmetry breaking reappears at positive temperature.

</DOC>
<DOC>
<DOCNO> 101808 </DOCNO>
$L^p$ version of a result by Rankin


  We extend a classical result by Rankin. We consider the
following question: given $n$ vectors $v_i$ in the ball of radius $R$ of an
infinite dimensional Banach space ${\cal B}$ with $d(v_i,v_j)\geq 1$, can we
bound the number $n$?

</DOC>
<DOC>
<DOCNO> 116399 </DOCNO>
New Hierarchic Theory of Matter, general for liquids and solids:


  This work contains basically new Hierarchic theory of condensed matter,
general for liquids and solids and its application to bulk water and ice,
including the region of liquid-solid phase transition. It is assumed that
unharmonic oscillations of particles in any condensed matter lead to emergence
of three-dimensional (3D) superposition of standing de Broglie waves of
molecules, electromagnetic and acoustic waves. Consequently, any condensed
matter can be considered as a gas of 3D standing waves of corresponding nature.
The analysis of interrelation between mesoscopic and macroscopic properties of
condensed matter, dynamics and thermodynamics is presented in this article. Lot
of hidden parameters, describing the dynamic and spatial parameters of 24
interrelated quantum collective excitations of matter can be calculated also
for water and ice, using our theory based computer program: Comprehensive
Analyzer of Matter Properties (CAMP). The total number of the external and
hidden parameters of condensed matter, which may be evaluated using CAMP, is
about 300. New theory is verified quantitatively on examples of water and ice.
All known temperature anomalies of water and ice may be described in the
framework of Hierarchic theory.

</DOC>
<DOC>
<DOCNO> 101263 </DOCNO>
Large Complex Structure Limits of K3 Surfaces


  Motivated by the picture of mirror symmetry suggested by Strominger, Yau and
Zaslow, we made a conjecture concerning the Gromov-Hausdorff limits of
Calabi-Yau n-folds (with Ricci-flat K\"ahler metric) as one approaches a large
complex structure limit point in moduli; a similar conjecture was made
independently by Kontsevich, Soibelman and Todorov. Roughly stated, the
conjecture says that, if the metrics are normalized to have constant diameter,
then this limit is the base of the conjectural special lagrangian torus
fibration associated with the large complex structure limit, namely an
n-sphere, and that the metric on this S^n is induced from a standard (singular)
Riemannian metric on the base, the singularities of the metric corresponding to
the discriminant locus of the fibration.
  This conjecture is trivially true for elliptic curves; in this paper we prove
it in the case of K3 surfaces. Using the standard description of mirror
symmetry for K3 surfaces and the hyperk\"ahler rotation trick, we reduce the
problem to that of studying K\"ahler degenerations of elliptic K3 surfaces,
with the K\"ahler class approaching the wall of the K\"ahler cone corresponding
to the fibration and the volume normalized to be one. Here we are able to write
down a remarkably accurate approximation to the Ricci-flat metric -- if the
elliptic fibres are of area $\epsilon >0$, then the error is
$O(e^{-C/\epsilon})$ for some constant $C>0$. This metric is obtained by gluing
together a semi-flat metric on the smooth part of the fibration with suitable
Ooguri-Vafa metrics near the singular fibres. For small $\epsilon$, this is a
sufficiently good approximation that the above conjecture is then an easy
consequence.

</DOC>
<DOC>
<DOCNO> 11257 </DOCNO>
A protein model exhibiting three folding transitions


  We explain the physical basis of a model for small globular proteins with
water interactions. The water is supposed to access the protein interior in an
"all-or-none" manner during the unfolding of the protein chain. As a
consequence of this mechanism (somewhat speculative), the model exhibits
fundamental aspects of protein thermodynamics, as cold, and warm unfolding of
the polypeptide chain, and hence decreasing the temperature below the cold
unfolding the protein folds again, accordingly the heat capacity has three
characteristic peaks. The cold and warm unfolding has a sharpness close to a
two-state system, while the cold folding is a transition where the intermediate
states in the folding is energetical close to the folded/unfolded states,
yielding a less sharp transition. The entropy of the protein chain causes both
the cold folding and the warm unfolding.

</DOC>
<DOC>
<DOCNO> 100495 </DOCNO>
On the Word and Period Growth of some Groups of Tree Automorphisms


  We generalize a class of groups defined by Rostislav Grigorchuk to a much
larger class of groups, and provide upper and lower bounds for their word
growth (they are all of intermediate growth) and period growth (under a small
additional condition, they are periodic).

</DOC>
<DOC>
<DOCNO> 122549 </DOCNO>
Radio Microlensing: Past, Present & Near Future


  Strongly correlated non-intrinsic variability between 5 and 8.5 GHz has been
observed in one of the lensed images of the gravitational lens B1600+434. These
non-intrinsic (i.e. `external') variations are interpreted as
`radio-microlensing' of relativistic micro-arsec-scale jet components in the
source at a redshift of z=1.59 by massive compact objects in the halo of the
edge-on disk lens galaxy at z=0.41. We shortly summarize these observations and
discuss several new observational and theoretical programs to investigate this
new phenomenon in more detail.

</DOC>
<DOC>
<DOCNO> 10950 </DOCNO>
Connection between vibrational dynamics and topological order in simple


  We compare vibrational dynamics in two structurally distinct, simple
monatomic model glasses simulated by molecular dynamics: the Lennard-Jones
glass with an fcc-related structure and a glass with predominantly icosahedral
short-range order. The former, characterised by a single local
quasi-periodicity, supports only modes with acoustic behaviour. In the latter,
the presence of optic modes and two incommensurate length scales is observed.
This pattern of vibrational dynamics is shown to be closely related to that of
a Frank-Kasper crystal having the same local topological order.

</DOC>
<DOC>
<DOCNO> 100713 </DOCNO>
An Arakelov theoretic proof of the equality of conductor and


  We give an Arakelov theoretic proof of the equality of conductor and
discriminant for arithmetic surfaces over number fields. This was first proved
by T. Saito for relative curves over discrete valuation rings.

</DOC>
<DOC>
<DOCNO> 68772 </DOCNO>
Mathematics for structure functions


  We show some of the mathematics that is being developed for the computation
of deep inelastic structure functions to three loops. These include harmonic
sums, harmonic polylogarithms and a class of difference equations that can be
solved with the use of harmonic sums.

</DOC>
<DOC>
<DOCNO> 99594 </DOCNO>
Spacings between phase shifts in a simple scattering problem


  We prove a scattering theoretical version of the Berry-Tabor conjecture: for
an almost every surface in a class of cylindrical surfaces of revolution, the
large energy limit of the pair correlation measure of the quantum phase shifts
is Poisson, that is, it is given by the uniform measure.

</DOC>
<DOC>
<DOCNO> 122690 </DOCNO>
Tests for primordial non-Gaussianity


  We investigate the relative sensitivities of several tests for deviations
from Gaussianity in the primordial distribution of density perturbations. We
consider models for non-Gaussianity that mimic that which comes from inflation
as well as that which comes from topological defects. The tests we consider
involve the cosmic microwave background (CMB), large-scale structure (LSS),
high-redshift galaxies, and the abundances and properties of clusters. We find
that the CMB is superior at finding non-Gaussianity in the primordial
gravitational potential (as inflation would produce), while observations of
high-redshift galaxies are much better suited to find non-Gaussianity that
resembles that expected from topological defects. We derive a simple expression
that relates the abundance of high-redshift objects in non-Gaussian models to
the primordial skewness.

</DOC>
<DOC>
<DOCNO> 150419 </DOCNO>
Multiple zero modes of the Dirac operator in three dimensions


  One of the key properties of Dirac operators is the possibility of a
degeneracy of zero modes. For the Abelian Dirac operator in three dimensions
the construction of multiple zero modes has been sucessfully carried out only
very recently. Here we generalise these results by discussing a much wider
class of Dirac operators together with their zero modes. Further we show that
those Dirac operators that do admit zero modes may be related to Hopf maps,
where the Hopf index is related to the number of zero modes in a simple way.

</DOC>
<DOC>
<DOCNO> 152161 </DOCNO>
Phases of Supersymmetric D-branes on Kaehler Manifolds and the McKay


  We study the topological zero mode sector of type II strings on a K\"ahler
manifold $X$ in the presence of boundaries. We construct two finite bases, in a
sense bosonic and fermionic, that generate the topological sector of the
Hilbert space with boundaries. The fermionic basis localizes on compact
submanifolds in $X$. A variation of the FI terms interpolates between the
description of these ground states in terms of the ring of chiral fields at the
boundary at small volume and helices of exceptional sheaves at large volume,
respectively. The identification of the bosonic/fermionic basis with the dual
bases for the non-compact/compact K-theory group on $X$ gives a natural
explanation of the McKay correspondence in terms of a linear sigma model and
suggests a simple generalization of McKay to singular resolutions. The
construction provides also a very effective way to describe D-brane states on
generic, compact Calabi--Yau manifolds and allows to recover detailed
information on the moduli space, such as monodromies and analytic continuation
matrices, from the group theoretical data of a simple orbifold.

</DOC>
<DOC>
<DOCNO> 68937 </DOCNO>
Radiative Symmetry Breaking in Brane Models


  We propose a way to generate the electroweak symmetry breaking radiatively in
non-supersymmetric type I models with string scale in the TeV region. By
identifying the Higgs field with a tree-level massless open string state, we
find that a negative squared mass term can be generated at one loop. It is
finite, computable and typically a loop factor smaller than the string scale,
that acts as an ultraviolet cutoff in the effective field theory. When the
Higgs open string has both ends confined on our world brane, its mass is
predicted to be around 120 GeV, i.e. that of the lightest Higgs in the minimal
supersymmetric model for large $\tan\beta$ and $m_A$. Moreover, the string
scale turns out to be one to two orders of magnitude higher than the weak
scale. We also discuss possible effects of higher order string threshold
corrections that might increase the string scale and the Higgs mass.

</DOC>
<DOC>
<DOCNO> 13723 </DOCNO>
An SU(4) Model of High-Temperature Superconductivity and


  We present an SU(4) model of high-temperature superconductivity having many
similarities to dynamical symmetries known to play an important role in
microscopic nuclear structure physics and in elementary particle physics.
Analytical solutions in three dynamical symmetry limits of this model are
found: an SO(4) limit associated with antiferromagnetic order; an SU(2) X SO(3)
limit that may be interpreted as a d-wave pairing condensate; and an SO(5)
limit that may be interpreted as a doorway state between the antiferromagnetic
order and the superconducting order. The model suggests a phase diagram in
qualitative agreement with that observed in the cuprate superconductors. The
relationship between the present model and the SO(5) unification of
superconductivity and antiferromagnetic order proposed by Zhang is discussed.

</DOC>
<DOC>
<DOCNO> 121629 </DOCNO>
Inhomogeneous Chemical Evolution of the Galactic Halo: Abundance of


  We present a stochastic model based on the Monte Carlo technique to study the
inhomogeneous chemical evolution of the Galactic halo. In particular, we
consider the local enrichment and subsequent mixing of the interstellar gas
resulting from bursts of star formation, following explicitly the fragmentation
and coalescence of interstellar gas clouds. The model takes into account the
mixing of halo gas through cloud-cloud collisions and the delayed mixing of
supernova ejecta into the interstellar medium. The consequences of the infall
of halo gas onto the Galactic disk are also discussed. The mass spectrum of
clouds, the age-metallicity relation, and the G-dwarf distribution are
investigated at different times. We analyze in detail the predictions of our
model for the abundance of elements like Eu, Ba, and Sr in the Galactic halo,
following their production by $r$-process nucleosynthesis for different
assumptions on the supernova mass range. Finally, we compare our results with
spectroscopic data for the chemical composition of metal-poor halo stars.

</DOC>
<DOC>
<DOCNO> 152091 </DOCNO>
Chaotic Quantization of Classical Gauge Fields


  We argue that higher dimensional classical, nonabelian gauge theory may lead
to a lower dimensional quantum field theory due to its inherent chaotic
dynamics which acts like stohastic quantization. The dimensional reduction is
based upon magnetic screening effects analagous to that in nonabelian plasmas.

</DOC>
<DOC>
<DOCNO> 120871 </DOCNO>
The TeV Energy Spectrum of Mkn 501 Measured with the Stereoscopic


  During 1997, the BL Lac object Mkn 501 went into an extraordinary state of
high X-ray and TeV gamma-ray activity, lasting more than 6 months. In this
paper we report on the TeV emission characteristics of the source in the
subsequent years of 1998 and 1999 as measured with the Stereoscopic Cherenkov
Telescope System of HEGRA (La Palma, Canary Islands). Our observations reveal a
1998-1999 mean emission level at 1 TeV of 1/3 of the flux of the Crab Nebula, a
factor of 10 lower than during the year of 1997. A dataset of 122 observations
hours with the HEGRA telescope system makes it possible to assess for the first
time the Mkn 501 TeV energy spectrum for a mean flux level substantially below
that of the Crab Nebula with reasonable statistical accuracy. Excluding the
data of a strong flare, we find evidence that the 1998--1999 low-flux spectrum
is substantially softer (by 0.44+-0.1(stat) in spectral index) than the 1997
time averaged spectrum. The 500 GeV to 10 TeV energy spectrum can well be
described by a power law model with exponential cutoff: dN/dE ~ E^(-alpha)
exp(-E/E0) with alpha=2.31+-0.22(stat), and E0=5.1 (-2.3+7.8)(stat) TeV. Within
statistical accuracy, also a pure power law model gives an acceptable fit to
the data: dN/dE ~ E^(-Gamma) with Gamma=2.76+-0.08(stat). After presenting the
1998-1999 TeV characteristics of the source we discuss the implications of the
results.

</DOC>
<DOC>
<DOCNO> 8627 </DOCNO>
Odor recognition and segmentation by a model olfactory bulb and cortex


  We present a model of an olfactory system that performs odor segmentation.
Based on the anatomy and physiology of natural olfactory systems, it consists
of a pair of coupled modules, bulb and cortex. The bulb encodes the odor inputs
as oscillating patterns. The cortex functions as an associative memory: When
the input from the bulb matches a pattern stored in the connections between its
units, the cortical units resonate in an oscillatory pattern characteristic of
that odor. Further circuitry transforms this oscillatory signal to a
slowly-varying feedback to the bulb. This feedback implements olfactory
segmentation by suppressing the bulbar response to the pre-existing odor,
thereby allowing subsequent odors to be singled out for recognition.

</DOC>
<DOC>
<DOCNO> 84565 </DOCNO>
Comment on "Viscous cosmology in the Kasner metric"


  We show in this comment that in an anisotropic Bianchi type I model of the
Kasner form, it is not possible to describe the growth of entropy, if we want
to keep the thermodynamics together with the dominant energy conditions. This
consequence disagrees with the results obtained by Brevik and Pettersen [Phys.
Rev. D 56, 3322 (1997)].

</DOC>
<DOC>
<DOCNO> 101544 </DOCNO>
Irreducibility criterion for tensor products of Yangian evaluation


  The evaluation homomorphisms from the Yangian Y(gl_n) to the universal
enveloping algebra U(gl_n) allow one to regard the irreducible
finite-dimensional representations of gl_n as Yangian modules. We give
necessary and sufficient conditions for irreducibility of tensor products of
such evaluation modules.

</DOC>
<DOC>
<DOCNO> 84363 </DOCNO>
The Transition from Inspiral to Plunge for a Compact Body in a Circular


  There are three regimes of gravitational-radiation-reaction-induced inspiral
for a compact body with mass mu, in a circular, equatorial orbit around a Kerr
black hole with mass M>>mu: (i) The "adiabatic inspiral regime", in which the
body gradually descends through a sequence of circular, geodesic orbits. (ii) A
"transition regime", near the innermost stable circular orbit (isco). (iii) The
"plunge regime", in which the body travels on a geodesic from slightly below
the isco into the hole's horizon. This paper gives an analytic treatment of the
transition regime and shows that, with some luck, gravitational waves from the
transition might be measurable by the space-based LISA mission.

</DOC>
<DOC>
<DOCNO> 70295 </DOCNO>
Excited Heavy Baryon Masses from the 1/N_c Expansion of HQET


  The mass spectra of the L=1 orbitally excited heavy baryons with light quarks
in both the spin-flavor symmetric and the mixed representations are studied by
the $1/N_c$ expansion method in the framework of the heavy quark effective
theory. The mixing effect between the baryons in the two representations is
also considered. The general pattern of the spectrum is predicted which will be
verified by the experiments in the near future.

</DOC>
<DOC>
<DOCNO> 11454 </DOCNO>
Plasticity and memory effects in the vortex solid phase of twinned


  We report on marked memory effects in the vortex system of twinned YBa2Cu3O7
single crystals observed in ac susceptibility measurements. We show that the
vortex system can be trapped in different metastable states with variable
degree of order arising in response to different system histories. The pressure
exerted by the oscillating ac field assists the vortex system in ordering,
locally reducing the critical current density in the penetrated outer zone of
the sample. The robustness of the ordered and disordered states together with
the spatial profile of the critical current density lead to the observed memory
effects.

</DOC>
<DOC>
<DOCNO> 117259 </DOCNO>
Reversed Dark Resonance in Rb Atom Excited by a Diode Laser


  Origin of recently discovered reversed (opposite sign) dark resonances was
explained theoretically and verified experimentally. It is shown that the
reason for these resonances is a specific optical pumping of ground state level
in a transition when ground state angular momentum is smaller than the excited
state momentum.

</DOC>
<DOC>
<DOCNO> 151988 </DOCNO>
Black Hole Radiation On and Off the Brane


  After a brief review of the description of black holes on branes, we examine
the evaporation of a small black hole on a brane in a world with large extra
dimensions. We show that, contrary to previous claims, most of the energy is
radiated into the modes on the brane. This raises the possibility of observing
Hawking radiation in future high energy colliders if there are large extra
dimensions.

</DOC>
<DOC>
<DOCNO> 178492 </DOCNO>
Rho-Nucleon Tensor Coupling and Charge-Exchange Resonances


  The Gamow-Teller resonances are discussed in the context of a self-consistent
RPA, based on the relativistic mean field theory. We inquire on the possibility
of substituting the phenomenological Landau-Migdal force by a microscopic
nucleon-nucleon interaction generated from the rho-nucleon tensor coupling. The
effect of this coupling turns out to be very small when the short range
correlations are not taken into account, but too large when these correlations
are simulated by the simple extraction of the contact terms from the resulting
nucleon-nucleon interaction.

</DOC>
<DOC>
<DOCNO> 169693 </DOCNO>
Phase properties of a new nonlinear coherent state


  We study phase properties of a displacement operator type nonlinear coherent
state. In particular we evaluate the Pegg-Barnett phase distribution and
compare it with phase distributions associated with the Husimi Q function and
the Wigner function. We also study number- phase squeezing of this state.

</DOC>
<DOC>
<DOCNO> 122137 </DOCNO>
Mining the local Universe: the QSO space density


  We present progress results of a new survey for bright QSOs (V<14.5, R<15.4,
B_J<15.2) covering the whole sky at high galactic latitudes, |b|>30. The
surface density of QSOs brighter than B_J=14.8 turns out to be 2.9 +- 0.8
10^{-3} deg^{-2}. The optical Luminosity Function at 0.04 < z < 0.3 shows
significant departures from the standard pure luminosity evolution, providing
new insights in the modelling of the QSO phenomenon.

</DOC>
<DOC>
<DOCNO> 151094 </DOCNO>
D-Branes in the Background of NS Fivebranes


  We study the dynamics of $D$-branes in the near-horizon geometry of $NS$
fivebranes. This leads to a holographically dual description of the physics of
$D$-branes ending on and/or intersecting $NS5$-branes. We use it to verify some
properties of such $D$-branes which were deduced indirectly in the past, and
discuss some instabilities of non-supersymmetric brane configurations. Our
construction also describes vacua of Little String Theory which are dual to
open plus closed string theory in asymptotically linear dilaton spacetimes.

</DOC>
<DOC>
<DOCNO> 117038 </DOCNO>
Coherently Controlled Nanoscale Molecular Deposition


  Quantum interference effects are shown to provide a means of controlling and
enhancing the focusing a collimated neutral molecular beam onto a surface. The
nature of the aperiodic pattern formed can be altered by varying laser field
characteristics and the system geometry.

</DOC>
<DOC>
<DOCNO> 178429 </DOCNO>
Equation of state of nucleonic matter


  The nuclear equation of state (EoS) is investigated by flow phenomena in
relativistic heavy-ion collisions, both in transverse and radial direction, in
comparison to experimental data from 150 A MeV to 11 A GeV. To this aim the
collective dynamics of the nucleus-nucleus collision is described within a
transport model of the coupled channel RBUU type. There are two factors which
dominantly determine the baryon flow at these energies: the momentum dependence
of the scalar ($U_S$) and vector potentials ($U_\mu$) for baryons and the
resonance/string degrees of freedom for energetic hadron excitations. We fix
the explicit momentum dependence of the nucleon-meson couplings by the nucleon
optical potential up to 1 GeV and extrapolate to higher energy. When assuming
the optical potential to vanish identically for $E_{kin} \geq 3.5$ GeV we
simultaneously describe the sideward flow data of the PLASTIC BALL, FOPI, EoS
and E877 collaborations, the elliptic flow data of the E895 and E877
collaborations and approximately the rapidity and transverse mass distribution
of protons at AGS energies without employing any {\it explicit} assumption on a
phase transition in the EoS. However, the gradual change from hadronic to
string degrees of freedom with increasing bombarding energy can be viewed as a
transition from {\it hadronic} to {\it string} matter, i.e. a dissolution of
hadrons at high energy density.

</DOC>
<DOC>
<DOCNO> 121874 </DOCNO>
Low-ionization structures in planetary nebulae: confronting models with


  Around 50 PNe are presently known to possess "small-scale" low-ionization
structures (LISs). We consider here jets, jet-like, symmetrical and
non-symmetrical LISs and present a detailed comparison of the existing model
predictions with the observational morphological and kinematical properties. We
find that nebulae with LISs appear indistinctly spread among all morphological
classes of PNe, indicating that the processes leading to the formation of LISs
are not necessarily related to those responsible for the asphericity of the
large-scale morphological components of PNe. We show that both the observed
velocities and locations of most non-symmetrical LISs can be reasonably well
reproduced assuming either fossil condensations originated in the AGB wind or
in-situ instabilities. The jet models proposed to date (HD and MHD interacting
winds or accretion-disk collimated winds) appear unable to account
simultaneously for the kinematical ages and the angle between the jet and the
symmetry axes of the nebulae. The linear increase in velocity observed in
several jets favors MHD confinement compared to pure HD interacting wind
models. On the other hand, we find that the formation of jet-like systems
characterized by relatively low expansion velocities cannot be explained by any
of the existing models. Finally, the knots which appear in symmetrical and
opposite pairs of low velocity could be understood as the survival of fossil
(symmetrical) condensations formed during the AGB phase or as structures that
have experienced substantial slowing down by the ambient medium.

</DOC>
<DOC>
<DOCNO> 116378 </DOCNO>
Diffraction Radiation Diagnostics for Moderate to High Energy Charged


  Diffraction radiation (DR) is produced when a charged particle passes through
an aperture or near a discontinuity in the media in which it is traveling. DR
is closely related to transition radiation (TR), which is produced when a
charged particle traverses the boundary between media with different dielectric
constants. In contrast to TR, which is now extensively used for beam diagnostic
purposes, the potential of DR as a non-interceptive, multi-parameter beam
diagnostic remains largely undeveloped. For diagnostic measurements it is
useful to observe backward reflected DR from an circular aperture or slit
inclined with respect to the beam velocity. However, up to now, well founded
equations for the spectral-angular intensities of backward DR from such
apertures have not been available. We present a new derivation of the spectral
angular intensity of backward DR produced from an inclined slit for two
orientations of the slit axis, i.e. perpendicular and parallel to the plane of
incidence. Our mathematical approach is generally applicable to any geometry
and simpler than the Wiener Hofp method previously used to calculate DR from
single knife edges. Our results for the slit are applied to the measurement of
orthogonal beam size and divergence components. We discuss the problem of
separating the simultaneous effects of these beam parameters on the angular
distribution of DR and provide solutions to this difficulty. These incude using
the horizontal and vertical polarization components of the radiation from a
single slit and interferences from two inclined slits. Examples of DR
diagnostics for a 500 MeV beam are presented and the current limitations to the
technique are discussed.

</DOC>
<DOC>
<DOCNO> 178929 </DOCNO>
Test of phi renormalization in nuclei through phi photoproduction


  We propose an experimental procedure to find out the medium modifications of
the $\phi$ meson. The reaction is inclusive $\phi$ photoproduction in nuclei,
looking for $K^+ K^-$ pairs from the $\phi$ decay with total momentum smaller
than 100-150 $MeV/c$, which are made possible at energies of present
laboratories from center of mass $\phi$ backward production and the help of
Fermi motion. We have conducted a many body calculation of the mass
distribution of the $\phi$ adapted to the experimental set up of a recent JLAB
experiment where the backwards $\phi$ photoproduction has been measured. Using
recent results for the in medium properties of the $\phi$, we find that the
width of the invariant mass distribution for photoproduction on medium to heavy
nuclei is larger than the free $\phi$ width by a factor of two or more.

</DOC>
<DOC>
<DOCNO> 71556 </DOCNO>
Strange Magnetic Moment of The Nucleon from Lattice QCD


  We calculate the strange magnetic moment of the nucleon on a quenched $16^3
\times 24$ lattice at $\beta = 6.0$, and with Wilson fermions at $\kappa$ =
0.148, 0.152, and 0.154. The strange quark contribution from the disconnected
insertion is estimated stochastically by employing the $Z_2$ noise method.
Using an unbiased subtraction along with the help of charge conjugation and
hermiticity, we reduce the error by a factor of 2 with negligible overhead. Our
result is $G_{M}^{s} = -0.28\pm0.10 \mu_{N}$.

</DOC>
<DOC>
<DOCNO> 121010 </DOCNO>
HI Recycling: Formation of Tidal Dwarf Galaxies


  Galactic collisions trigger a number of phenomena, such as transportation
inward of gas from distances of up to kiloparsecs from the center of a galaxy
to the nuclear region, fuelling a central starburst or nuclear activity. The
inverse process, the ejection of material into the intergalactic medium by
tidal forces, is another important aspect and can be studied especially well
through detailed HI observations of interacting systems which have shown that a
large fraction of the gaseous component of colliding galaxies can be expelled.
Part of this tidal debris might fall back, be dispersed throughout the
intergalactic medium or recondense to form a new generation of galaxies: the
so-called tidal dwarf galaxies. The latter are nearby examples of galaxies in
formation. The properties of these recycled objects are reviewed here and
different ways to identify them are reviewed.

</DOC>
<DOC>
<DOCNO> 71640 </DOCNO>
Dyson-Schwinger Equations - aspects of the pion


  The contemporary use of Dyson-Schwinger equations in hadronic physics is
exemplified via applications to the calculation of pseudoscalar meson masses,
and inclusive deep inelastic scattering with a determination of the pion's
valence-quark distribution function.

</DOC>
<DOC>
<DOCNO> 11279 </DOCNO>
Cooper Pairs in Alternating Layers of Light and Heavy Atoms


  The Hamiltonian and trial function in the BCS theory are improved to test the
limit of this theory. The Cooper pairs arise from standing electron waves,
ready to move with atoms, giving high Tc. The Hamiltonian is derived from
alternating layers of light and heavy atoms, giving a forbidden zone hosting no
standing wave pairs. The exchange term may force singlet pairs into this zone,
leaving triplet pairs outside, giving magnetic excitations. If the Fermi energy
is crossed only by the CuO2 band, then the forbidden zone and triplet pairs
will vanish, consistent with experimental evidence.

</DOC>
<DOC>
<DOCNO> 84497 </DOCNO>
Regular (2+1)-dimensional black holes within non-linear Electrodynamics


  (2+1)-regular static black hole solutions with a nonlinear electric field are
derived. The source to the Einstein equations is an energy momentum tensor of
nonlinear electrodynamics, which satisfies the weak energy conditions and in
the weak field limit becomes the (2+1)-Maxwell field tensor. The derived class
of solutions is regular; the metric, curvature invariants and electric field
are regular everywhere. The metric becomes, for a vanishing parameter, the
(2+1)-static charged BTZ solution. A general procedure to derive solutions for
the static BTZ (2+1)-spacetime, for any nonlinear Lagrangian depending on the
electric field is formulated; for relevant electric fields one requires the
fulfillment of the weak energy conditions.

</DOC>
<DOC>
<DOCNO> 116526 </DOCNO>
Testing cosmological variability of fundamental constants


  One of the topical problems of contemporary physics is a possible variability
of the fundamental constants. Here we consider possible variability of two
dimensionless constants which are most important for calculation of atomic and
molecular spectra (in particular, the X-ray ones): the fine-structure constant
\alpha=e^2/\hbar c and the proton-to-electron mass ratio \mu=m_p/m_e. Values of
the physical constants in the early epochs are estimated directly from
observations of quasars - the most powerful sources of radiation, whose spectra
were formed when the Universe was several times younger than now. A critical
analysis of the available results leads to the conclusion that present-day data
do not reveal any statistically significant evidence for variations of the
fundamental constants under study. The most reliable upper limits to possible
variation rates at the 95% confidence level, obtained in our work, read:
  |\dot\alpha/\alpha| < (1.4e-14)/yr,
  |\dot\mu/\mu| < (1.5e-14)/yr 
 on the average over the last ten billion years.

</DOC>
<DOC>
<DOCNO> 100882 </DOCNO>
On the Reidemeister torsion of rational homology spheres


  We prove that the mod Z reduction of the torsion of a rational homology
3-sphere is completely determined by three data: a certain canonical spin^c
structure, the linking form and a Q/Z-valued constant c. This constant is a new
topological invariant of the rational homology sphere. Experimentations with
lens spaces suggest this constant may be as powerful an invariant as the
torsion itself.

</DOC>
<DOC>
<DOCNO> 10331 </DOCNO>
Magnetic-Field-Driven Superconductor-Insulator-Type Transition in


  A magnetic-field-driven transition from metallic- to semiconducting-type
behavior in the basal-plane resistance takes place in highly oriented pyrolytic
graphite at a field $H_c \sim 1~$kOe applied along the hexagonal c-axis. The
analysis of the data reveals a striking similarity between this transition and
that measured in thin-film superconductors and Si MOSFET's. However, in
contrast to those materials, the transition in graphite is observable at almost
two orders of magnitude higher temperatures.

</DOC>
<DOC>
<DOCNO> 71762 </DOCNO>
Screening length, dispersion relations and quark potential in thermo


  The screening length in a quark-gluon plasma, the dispersion relations of
thermal gluon self-energy and the quark potential at high temperature are
studied within thermo field dynamics framework. By calculation of the real and
imaginary parts, of the gluon self-energy in one-loop order in thermo field
dynamics, we obtain an expression for the screening length in a quark-gluon
plasma and the dispersion relation between the real and imaginary parts. At
high temperature, using photon exchange between electron-positron in a skeleton
expansion and ladder approximation, the screened Coulomb potential is obtained,
and using one-gluon and two-gluon exchange between a quark-antiquark, we get an
expression for the screened quark potential up to $O(g amplitudes of generic
process taking place in a many body system in equilibrium at temperature T. The
relationship of the scattering and decay amplitudes as calculated in Thermo
Field Dynamics to the conventional techniques is established. It is shown that
in many cases the calculations are relatively easy in TFD.

</DOC>
<DOC>
<DOCNO> 70842 </DOCNO>
Topological defects in lattice gauge theories


  We present a non-perturbative formalism for measuring defect free energies
(monopole mass or vortex tension) in three-dimensional SU(2)+adjoint Higgs
models. Starting from twisted, translation invariant boundary conditions, we
perform a change of variables that allows us to express the defect free
energies in terms of 't Hooft loops. We propose that the defect free energies
can be used to distinguish between phases in this model, and also more
generally in other gauge field theories where no local order parameters exist.
In the case of monopoles, our construction can also be used in four-dimensional
pure-gauge SU(2) theory, where it gives the monopole mass in the maximally
Abelian gauge without the need of actually fixing the gauge in the simulation.
Moreover, the expression is manifestly independent of the choice of the Abelian
projection as long as it is compatible with the classical 't Hooft-Polyakov
solution.

</DOC>
<DOC>
<DOCNO> 80673 </DOCNO>
Algebraic Generalization of the Ginsparg-Wilson Relation


  A specific algebraic realization of the Ginsparg-Wilson relation in the form
$\gamma_{5}(\gamma_{5}D)+(\gamma_{5}D)\gamma_{5} =
  2a^{2k+1}(\gamma_{5}D)^{2k+2}$ is discussed, where $k$ stands for a
non-negative integer and $k=0$ corresponds to the commonly discussed
Ginsparg-Wilson relation. From a view point of algebra, a characteristic
property of our proposal is that we have a closed algebraic relation for one
unknown operator $D$, although this relation itself is obtained from the
original proposal of Ginsparg and Wilson,
$\gamma_{5}D+D\gamma_{5}=2aD\gamma_{5} \alpha D$, by choosing $\alpha$ as an
operator containing $D$ (and thus Dirac matrices). In this paper, it is shown
that we can construct the operator $D$ explicitly for any value of $k$. We
first show that the instanton-related index of all these operators is
identical. We then illustrate in detail a generalization of Neuberger's overlap
Dirac operator to the case $k=1$. On the basis of explicit construction, it is
shown that the chiral symmetry breaking term becomes more irrelevent for larger
$k$ in the sense of Wilsonian renormalization group. We thus have an infinite
tower of new lattice Dirac operators which are topologically proper, but a
large enough lattice is required to accomodate a Dirac operator with a large
value of $k$.

</DOC>
<DOC>
<DOCNO> 84910 </DOCNO>
Global monopoles in the Brans-Dicke theory


  A gravitating global monopole produces a repulsive grativational field
outside the core in addition to a solid angular deficit in the Brans-Dicke
theory. As a new feature, the angular deficit is dependent on the values of
\phi_{\infty} and \omega, where \phi_{\infty} is asymptotic value of scalar
field in space-like infinity and \omega is the Brans-Dicke parameter.

</DOC>
<DOC>
<DOCNO> 101893 </DOCNO>
Quantum cohomology of flag manifolds


  The (small) quantum cohomology ring of a flag manifold F encodes enumerative
geometry of rational curves on F. We give a proof of the presentation of the
ring and of a quantum Giambelli formula, which is more direct and geometric
than the previously known proof. Furthermore, this proof gives a relationship
between quantum Schubert polynomials and universal Schubert polynomials, which
arise in a degeneracy locus formula of Fulton.

</DOC>
<DOC>
<DOCNO> 100503 </DOCNO>
The cover time, the blanket time, and the Matthews bound


  The cover time C of a graph G is the expected time for a random walk starting
from the worst vertex to cover all vertices in G. Similarly, the blanket time B
is the expected time to visit all vertices within a constant factor of number
of times suggested by the stationary distribution. (Our definition will be
slightly stronger than this.) Obviously, all vertices are covered when the
graph is blanketed, and hence C <= B. The blanket time is introduced by Winkler
and Zuckerman motivated by applications in Markov estimation and distributed
computing. They conjectured B =O(C) and proved B=O(C ln n ). In this paper, we
introduce another parameter M motivated by Matthews' theorem and prove
  M/2 <= C <= B = O(( M ln ln n)^2).
  In particular, B = O(C (ln ln n)^2). The lower bound is still valid for the
cover time C(\pi) starting from the stationary distribution. We also show that
there is a polynomial time algorithm to approximate M within a factor of 2 and
so does for C within a factor of O((ln ln n)^2), improving previous bound of
O(ln n) of Matthews'.

</DOC>
<DOC>
<DOCNO> 119566 </DOCNO>
Jets from black hole binaries and Galactic Nuclei


  Relativistic outflows are a common phenomenon in accreting black holes.
Despite the enormous differences in scale, stellar-mass black holes in binaries
and supermassive black holes in Galactic Nuclei produce jets with analogous
properties. In both are observed two types of relativistic outflows: 1) steady
compact jets with flat-spectrum, and 2) sporadic extended jets with
steep-spectrum and apparent superluminal motions. Besides, the most common
class of gamma-ray bursts are afterglows from ultra-relativistic jets
associated to the formation of black holes at cosmological distances.

</DOC>
<DOC>
<DOCNO> 179019 </DOCNO>
The E2/M1 and C2/M1 ratios and form factors in N -> Delta transitions


  A partial wave analysis of pion photoproduction has been obtained in the
framework of fixed-t dispersion relations valid from threshold up to 500 MeV.
In the resonance region we have precisely determined the electromagnetic
properties of the \Delta(1232) resonance, in particular the E2/M1 ratio
R_{EM}=(-2.5 +- 0.1) %. For pion electroproduction recent experimental data
from Mainz, Bates and JLab for Q^2 up to 4.0 (GeV/c)^2 have been analyzed with
two different models, an isobar model (MAID) and a dynamical model. The E2/M1
ratios extracted with these two models show, starting from a small and negative
value at the real photon point, a clear tendency to cross zero, and become
positive with increasing Q^2. This is a possible indication of a very slow
approach toward the pQCD region. The C2/M1 ratio near the photon point is found
as R_{SM}(0)=(-6.5 +- 0.5) %. At high Q^2 the absolute value of the ratio is
strongly increasing, a further indication that pQCD is not yet reached.

</DOC>
<DOC>
<DOCNO> 69075 </DOCNO>
Naturalness of the Coleman-Glashow Mass Relation in the 1/N_c Expansion:


  A new measurement of the Xi^0 mass verifies the accuracy of the
Coleman-Glashow relation at the level predicted by the 1/N_c expansion. Values
for other baryon isospin mass splittings are updated, and continue to agree
with the 1/N_c hierarchy.

</DOC>
<DOC>
<DOCNO> 122950 </DOCNO>
Helium contamination from the progenitor stars of planetary nebulae: The


  In this work, two aspects of the chemical evolution of 4He in the Galaxy are
considered on the basis of a sample of disk planetary nebulae (PN). First, an
application of corrections owing to the contamination of 4He from the evolution
of the progenitor stars shows that the He/H abundance by number of atoms is
reduced by 0.012 to 0.015 in average, leading to an essentially flat He/H
radial distribution. Second, a determination of the helium to heavy element
enrichment ratio using the same corrections leads to values in the range 2.8 <
Delta Y/Delta Z < 3.6 for Yp = 0.23 and 2.0 < Delta Y/Delta Z < 2.8 for Yp =
0.24, in good agreement with recent independent determinations and theoretical
models.

</DOC>
<DOC>
<DOCNO> 40504 </DOCNO>
First CP Violation Results from BABAR


  We present a preliminary measurement of time-dependent CP-violating
asymmetries in B^0-->J/psi K_S and B^0-->psi(2S) K_S decays recorded by the
BABAR detector at the PEP-II asymmetric B Factory at SLAC. The data sample
consists of 9.0 fb-1 collected at the Upsilon(4S) resonance and 0.8 fb-1
off-resonance. One of the neutral B mesons, produced in pairs at the
Upsilon(4S), is fully reconstructed. The flavor of the other neutral B meson is
tagged at the time of its decay, mainly with the charge of identified leptons
and kaons. The time difference between the decays is determined by measuring
the distance between the decay vertices. Wrong-tag probabilities and the time
resolution function are measured with samples of fully-reconstructed
semileptonic and hadronic neutral B final states. The value of the asymmetry
amplitude, sin(2*beta), is determined from a maximum likelihood fit to the time
distribution of 120 tagged B^0-->J/psi K_S and B^0-->psi(2S) K_S candidates:
sin(2*beta) = 0.12+/-0.37(stat)+/-0.09(syst).

</DOC>
<DOC>
<DOCNO> 102501 </DOCNO>
Theta functions, quantum tori and Heisenberg groups


  A linear algebraic group $G$ is represented by the linear space of its
algebraic functions $F(G)$ endowed with multiplication and comultiplication
which turn it into a Hopf algebra. Supplying $G$ with a Poisson structure, we
get a quantized version $F_q(G)$ which has the same linear structure and
comultiplication, but deformed multiplication. This paper develops a similar
theory for abelian varieties. A description of abelian varieties $A$ in terms
of linear algebra data was given by Mumford: $F(G)$ is replaced by the graded
ring of theta functions with symmetric automorphy factors, and comultiplication
is replaced by the Mumford morphism $M^*$ acting on pairs of points as
$M(x,y)=M(x+y,x-y).$ After supplementing this by a Poisson structure and
replacing the classical theta functions by the quantized ones, introduced by
the author earlier, we obtain a structure which essentially coincides with the
classical one so far as comultiplication is concerned, but has a deformed
multiplication which moreover becomes only partial. The classical graded ring
is thus replaced by a linear category. Another important difference from the
linear case is that abelian varieties with different period groups (for
multiplication) and different quantization parameters (for comultiplication)
become interconnected after quantization.

</DOC>
<DOC>
<DOCNO> 84994 </DOCNO>
A variability analysis of low-latitude unidentified gamma-ray sources


  We present a study of 40 low-latitude unidentified 3EG gamma-ray sources
which were found to be not positionally coincident with any known class of
potential gamma-ray emitters in the Galaxy (Romero, Benaglia & Torres, 1999).
We have performed a variability analysis which reveals that many of these 40
sources are variable. These sources have, in addition, a steep mean value of
the gamma-ray spectral index, $<\Gamma> = 2.41 \pm 0.2$, which, combined with
the high level of variability seems to rule out a pulsar origin. The positional
coincidences with uncatalogued candidates to supernova remnants were also
studied. Only 7 sources in the sample are spatially coincident with these
candidates, a result that is shown to be consistent with the expected level of
pure chance association. A complementary search for weak radio counterparts was
also conducted and the results are presented as an extensive table containing
all significant point-like radio sources within the 40 EGRET fields. We argue
that in order to produce the high variability, steep gamma-ray spectra, and
absence of strong radio counterparts observed in some of the gamma-ray sources
of our sample a new class of objects should be postulated, and we analyze a
viable candidate.

</DOC>
<DOC>
<DOCNO> 84625 </DOCNO>
Relative velocity and relative acceleration induced by the torsion in


  The influence of the torsion on the relative velocity and on the relative
acceleration between particles (points) in spaces with an affine connection and
a metric [$(L_n,g)$-spaces] and in (pseudo) Riemannian spaces with torsion
($U_n$-spaces) is considered. Necessary and sufficient conditions as well as
only necessary and only sufficient conditions for vanishing deformation, shear,
rotation and expansion are found. The notion of relative acceleration and the
related to it notions of shear, rotation and expansion accelerations induced by
the torsion are determined. It is shown that the kinematic characteristics
induced by the torsion (shear acceleration, rotation acceleration and expansion
acceleration) could play the same role as the kinematic characteristics induced
by the curvature and can (under given conditions) compensate their action as
well as the action of external forces.
 The change of the rate of change of the length of a deviation vector field is
given in explicit form for $(L_n,g)$- and $U_n$-spaces.
      PACS numbers: 04.90+e, 04.50+h, 12.10.Gq, 03.40.-t

</DOC>
<DOC>
<DOCNO> 152077 </DOCNO>
Super Yang-Mills Operators from the D3-brane Action in a Curved


  A consistent truncation of IIB on S^5 has been obtained in the sector of the
metric and the 4-form potential. The ansatz contains 20 scalars and all 15
gauge fields of ${\cal N}=8$ gauged supergravity in five dimensions. With this
fully non-linear ansatz, the calculations for n-point correlators of super
Yang-Mills (SYM) theory via AdS/CFT are simpler than those in the literature
that use {\em linear} ansatz followed by non-linear field redefinitions. We
work out the SYM operators that couple to the scalars by expanding the
Dirac-Born-Infeld (DBI) action plus Wess-Zumino (WZ) terms around an
$AdS_5\timesS^5$ background with the metric fluctuations. The resulting
operators agree with those based on a superconformal symmetry argument. We
discuss the significance of our results.

</DOC>
<DOC>
<DOCNO> 121676 </DOCNO>
The Dwarf Galaxy Population of the Dorado group down to Mv=-11


  We present V and I CCD photometry of suspected low-surface brightness dwarf
galaxies detected in a survey covering ~2.4 deg^2 around the central region of
the Dorado group of galaxies. The low-surface brightness galaxies were chosen
based on their sizes and magnitudes at the limiting isophote of 26.0V\mu. The
selected galaxies have magnitudes brighter than V=20 (Mv=-11 for an assumed
distance to the group of 17.2 Mpc), with central surface brightnesses \mu0>22.5
V mag/arcsec^2, scale lengths h>2'', and diameters > 14'' at the limiting
isophote. Using these criteria, we identified 69 dwarf galaxy candidates. Four
of them are large very low-surface brightness galaxies that were detected on a
smoothed image, after masking high surface brightness objects. Monte Carlo
simulations performed to estimate completeness, photometric uncertainties and
to evaluate our ability to detect extended low-surface brightness galaxies show
that the completeness fraction is, on average, > 80% for dwarf galaxies with
$-17<M_{V}<-10.5$ and 22.5<\mu0<25.5 V mag/arcsec^2, for the range of sizes
considered by us (D>14''). The V-I colors of the dwarf candidates vary from
-0.3 to 2.3 with a peak on V-I=0.98, suggesting a range of different stellar
populations in these galaxies. The projected surface density of the dwarf
galaxies shows a concentration towards the group center similar in extent to
that found around five X-ray groups and the elliptical galaxy NGC1132 studied
by Mulchaey and Zabludoff (1999), suggesting that the dwarf galaxies in Dorado
are probably physically associated with the overall potential well of the
group.

</DOC>
<DOC>
<DOCNO> 151686 </DOCNO>
On the phase structure of two--dimensional generalized Yang--Mills


  The phase structure of the generalized Yang--Mills theories is studied, and
it is shown that {\it almost} always, it is of the third order. As a specific
example, it is shown that all of the models with the interaction $\sum_j
(n_j-j+N)^{2k}$ exhibit third order phase transition. ($n_j$ is the length of
the $j$-th row of the Yang tableau corresponding to U($N$).) The special cases
where the transition is not of the third order are also considered and, as a
specific example, it is shown that the model $\sum_j (n_j-j+N)^2+g\sum_j
(n_j-j+N)^{4}$ exhibits a third order phase transition, except for
$g=27\pi^2/256$, where the order of the transition is 5/2.

</DOC>
<DOC>
<DOCNO> 120242 </DOCNO>
Cosmology from Maxima-1, Boomerang and COBE/DMR CMB Observations


  Recent results from BOOMERANG-98 and MAXIMA-1, taken together with COBE-DMR,
provide consistent and high signal-to-noise measurements of the CMB power
spectrum at spherical harmonic multipole bands over $2<\ell\lta800$. Analysis
of the combined data yields 68% (95%) confidence limits on the total density,
$\Omega_{\rm {tot}}\simeq 1.11 \pm 0.07 (^{+0.13}_{-0.12})$, the baryon
density, $\Omega_b h^2\simeq 0.032^{+0.005}_{-0.004} (^{+0.009}_{-0.008})$, and
the scalar spectral tilt, $n_s\simeq1.01^{+0.09}_{-0.07} (^{+0.17}_{-0.14})$.
These data are consistent with inflationary initial conditions for structure
formation. Taken together with other cosmological observations, they imply the
existence of both non-baryonic dark matter and dark energy in the universe.

</DOC>
<DOC>
<DOCNO> 13827 </DOCNO>
Computational complexity for physicists


  These lecture notes are an informal introduction to the theory of
computational complexity and its links to quantum computing and statistical
mechanics.

</DOC>
<DOC>
<DOCNO> 40031 </DOCNO>
A search for charmonium states produced in central pp interactions at


  A search for centrally produced charmonium states has been presented. There
is no significant evidence for any charmonium production. An upper limit of 2
nb is found for the cross section of chic production using the decay chic(1P)->
J/psi gamma.

</DOC>
<DOC>
<DOCNO> 116287 </DOCNO>
Spectrum of atomic radiation at sudden perturbation


  A general expression for the spectrum of photons emitted by atom at sudden
perturbation is obtained. Some concrete examples of application of the obtained
result are considered. The conclusion about the coherence of radiation of the
atomic electrons under the such influences is made. PACS numbers: 32.30.*

</DOC>
<DOC>
<DOCNO> 119760 </DOCNO>
FUSE Spectroscopy of High Velocity Cloud Complex C


  We present Far Ultraviolet Spectroscopic Explorer (FUSE) observations of the
sightline toward the Seyfert 1 galaxy Markarian 876, which passes through high
velocity cloud (HVC) complex C. This sight line demonstrates the ability of
FUSE to measure ionic absorption lines in Galactic HVCs. High velocity
absorption is clearly seen in both members of the O VI doublet. This is the
first detection of O VI in a neutral hydrogen HVC. One component of HVC complex
C is resolved in multiple Fe II lines from which we derive N(Fe II)/N(H I)=0.48
(Fe/H)_solar. This value of N(Fe II)/N(H I) implies that the metallicity of
complex C along this sightline may be higher than that along the Mrk 290
sightline (0.1 solar) found by Wakker et al. (1999). On the other hand, if the
metallicity of complex C is also 0.1 solar along this line of sight, the
observed value of N(Fe II)/(N(H I) suggests there may be a significan t amount
of H+ along the line of sight. In any case, little, if any, iron can be
depleted into dust grains if the intrinsic metallicity of complex C is
subsolar. Absorption from complex C is also seen in C II, N I, and N II, and
upper limits based on non-detections can be determined for Ar I, P II, and Fe
III. Although molecular hydrogen in the Milky Way is obvious in the FUSE data,
no H_2 absorption is seen in the high velocity cloud to a limit
N(H_2)<2.0x10^14 cm^-2. Future FUSE observations of extragalactic objects
behind Galactic high velocity clouds will allow us to better constrain models
of HVC origins.

</DOC>
<DOC>
<DOCNO> 118126 </DOCNO>
An 11.6 Micron Keck Search For Exozodiacal Dust


  We have begun an observational program to search nearby stars for dust disks
that are analogous to the disk of zodiacal dust that fills the interior of our
solar system. We imaged six nearby main-sequence stars with the Keck telescope
at 11.6 microns, correcting for atmosphere-induced wavefront aberrations and
deconvolving the point spread function via classical speckle analysis. We
compare our data to a simple model of the zodiacal dust in our own system based
on COBE/DIRBE observations and place upper limits on the density of exozodiacal
dust in these systems.

</DOC>
<DOC>
<DOCNO> 67989 </DOCNO>
From Neutrino Masses to Proton Decay


  Current theoretical and experimental issues are reviewed in the light of the
recent SuperKamiokande discovery. By using quark-lepton symmetries, derived
from Grand Unification and/or string theories, we show how to determine the
necessary neutrino parameters. In addition, the seesaw neutrino masses set the
scale for the proton decay operators by ``measuring'' the standard model
cut-off. The SuperKamiokande values suggest that proton decay is likely to be
observed early in the XXIst Century.

</DOC>
<DOC>
<DOCNO> 152048 </DOCNO>
Seiberg-Witten Theories, Integrable Models and Perturbative


  This is a very brief review of relations between Seiberg-Witten theories and
integrable systems with emphasis on the perturbative prepotentials presented at
the E.S.Fradkin Memorial Conference.

</DOC>
<DOC>
<DOCNO> 8949 </DOCNO>
Random Resistor-Diode Networks and the Crossover from Isotropic to


  By employing the methods of renormalized field theory we show that the
percolation behavior of random resistor-diode networks near the multicritical
line belongs to the universality class of isotropic percolation. We construct a
mesoscopic model from the general epidemic process by including a relevant
isotropy-breaking perturbation. We present a two-loop calculation of the
crossover exponent $\phi$. Upon blending the $\epsilon$-expansion result with
the exact value $\phi =1$ for one dimension by a rational approximation, we
obtain for two dimensions $\phi = 1.29\pm 0.05$. This value is in agreement
with the recent simulations of a two-dimensional random diode network by Inui,
Kakuno, Tretyakov, Komatsu, and Kameoka, who found an order parameter exponent
$\beta$ different from those of isotropic and directed percolation.
Furthermore, we reconsider the theory of the full crossover from isotropic to
directed percolation by Frey, T\"{a}uber, and Schwabl and clear up some minor
shortcomings.

</DOC>
<DOC>
<DOCNO> 11245 </DOCNO>
Spin polarised carrier injection into high T_c superconductor: A test


  We point out in this short communique, that be it a s-wave or d-wave
superconductor, in a non equalibrium situation(i.e. in presence of excess
unpolarised/polarised quasi-particles maintained by an injection current) the
superconducting gap suppresion by the presence of same amount excess
quasi-particles, can at best differ by a factor of 2, for a conventional BCS
superconductor. For the high $T_c$ superconductors on the other hand, there is
a huge difference in gap suppresion between upolarised/polarised quasiparticle
injection, as observed in the experiments\cite{gold}. We argue that this this
large anomaly has a natural explanation within the {\it Interleyer tunneling
mechanism} of Wheatley, Hsu and Anderson\cite{and}, and is due to the excess
polarised quasiparticles blocking the interlayer pair tunneling process. We
also point out that spin polarised quasi-particle injection in a superconductor
is a very easy way to distinguish between a s-wave or an anisotropic gap
superconductor.

</DOC>
<DOC>
<DOCNO> 71372 </DOCNO>
Dynamical Topology Change in M Theory


  We study topology change in M theory compactifications on Calabi-Yau
three-folds in the presence of G flux (the four form field strength). In
particular, we discuss vacuum solutions in strongly coupled heterotic string
theory in which the topology change is inevitable within a single spacetime
background. For rather generic choices of initial conditions, the field
equations drive the Kahler moduli outside the classical moduli space of a
Calabi-Yau manifold. Consistency of the solution suggests that degenerate flop
curves - just as wrapped M theory fivebranes - carry magnetic charges under the
four form field strength.

</DOC>
<DOC>
<DOCNO> 10162 </DOCNO>
Hopf term induced by fermions


  We derive an effective action for Dirac fermions coupled to O(3) non-linear
sigma-model (NLSM) through the Yukawa-type interaction. The nonperturbative
(global) quantum anomaly of this model results in a Hopf term for the effective
NLSM. We obtain this term using the ``embedding'' of the CP$^1$ model into the
CP$^M$ generalization of the model which makes the quantum anomaly
perturbative. This perturbative anomaly is calculated by means of a gradient
expansion of a fermionic determinant and is given by the Chern-Simons term for
an auxiliary gauge field.

</DOC>
<DOC>
<DOCNO> 11776 </DOCNO>
Resonant X-Ray Magnetic Scattering from CoO


  We analyze the recent experiment [W. Neubeck {\em et al.}, Phys. Rev. B
\vol(60,1999,R9912)] for the resonant x-ray magnetic scattering (RXMS) around
the K edge of Co in the antiferromagnet CoO. We propose a mechanism of the RXMS
to make the $4p$ states couple to the magnetic order: the intraatomic exchange
interaction between the $4p$ and the $3d$ states and the $p$-$d$ mixing to the
$3d$ states of neighboring Co atoms. These couplings induce the orbital moment
in the $4p$ states and make the scattering tensor antisymmetric. Using a
cluster model, we demonstrate that this modification gives rise to a large RXMS
intensity in the dipole process, in good agreement with the experiment. We also
find that the pre-edge peak is generated by the transition to the $3d$ states
in the quadrupole process, with negligible contribution of the dipole process.
We also discuss the azimuthal angle dependence of the intensity.

</DOC>
<DOC>
<DOCNO> 116574 </DOCNO>
Atomic coherence and interference phenomena in resonant nonlinear


  Interference effects in quantum transitions, giving rise to amplification
without inversion, optical transparency and to enhancements in nonlinear
optical frequency conversions are considered. Review of the relevant early
theoretical and experimental results is given. The role of relaxation
processes, spontaneous cascade of polarizations, local field effects,
Doppler-broadening, as well as specific features of the interference in the
spectral continuum are discussed.

</DOC>
<DOC>
<DOCNO> 169974 </DOCNO>
Darboux-integration of id\rho/dt=[H,f(\rho)]


  A Darboux-type method of solving the nonlinear von Neumann equation $i\dot
\rho=[H,f(\rho)]$, with functions $f(\rho)$ commuting with $\rho$, is
developed. The technique is based on a representation of the nonlinear equation
by a compatibility condition for an overdetermined linear system. von Neumann
equations with various nonlinearities $f(\rho)$ are found to possess the
so-called self-scattering solutions. To illustrate the result we consider the
Hamiltonian $H$ of a one-dimensional harmonic oscillator and
$f(\rho)=\rho^q-2\rho^{q-1}$ with arbitary real $q$. It is shown that
self-scattering solutions possess the same asymptotics for all $q$ and that
different nonlinearities may lead to effectively indistinguishable evolutions.
The result may have implications for nonextensive statistics and experimental
tests of linearity of quantum mechanics.

</DOC>
<DOC>
<DOCNO> 117906 </DOCNO>
Runaway of Line-Driven Winds Towards Critical and Overloaded solutions


  Line-driven winds from hot stars and accretion disks are thought to adopt a
unique, critical solution which corresponds to maximum mass loss rate and a
particular velocity law. We show that in the presence of negative velocity
gradients, radiative-acoustic (Abbott) waves can drive shallow wind solutions
towards larger velocities and mass loss rates. Perturbations introduced
downstream from the wind critical point lead to convergence towards the
critical solution. By contrast, low-lying perturbations cause evolution towards
a mass-overloaded solution, developing a broad deceleration region in the wind.
Such a wind differs fundamentally from the critical solution. For sufficiently
deep-seated perturbations, overloaded solutions become time-dependent and
develop shocks and shells.

</DOC>
<DOC>
<DOCNO> 121681 </DOCNO>
Inflationary perturbations near horizon crossing


  We study the behaviour of inflationary density perturbations in the vicinity
of horizon crossing, using numerical evolution of the relevant mode equations.
We explore two specific scenarios. In one, inflation is temporarily ended
because a portion of the potential is too steep to support inflation. We find
that perturbations on super-horizon scales can be modified, usually leading to
a large amplification, because of entropy perturbations in the scalar field.
This leads to a broad feature in the power spectrum, and the slow-roll and
Stewart--Lyth approximations, which assume the perturbations reach an
asymptotic regime well outside the horizon, can fail by many orders of
magnitude in this regime. In the second scenario we consider perturbations
generated right at the end of inflation, which re-enter shortly after inflation
ends --- such perturbations can be relevant for primordial black hole
formation.

</DOC>
<DOC>
<DOCNO> 71288 </DOCNO>
Preheating - cosmic magnetic dynamo ?


  We study the amplification of large-scale magnetic fields during preheating
and inflation in several different models. Preheating can resonantly amplify
seed fields on cosmological scales. In the presence of conductivity, however,
the effect of resonance is typically weakened while the amplitude of produced
magnetic fields depends sensitively on the evolution of the conductivity during
the preheating and thermalisation phases. In addition we discuss geometric
magnetisation, where amplification of magnetic fields occurs through coupling
to curvature invariants. This can be efficient during inflation due to a
negative coupling instability. Finally we discuss the breaking of the conformal
flatness of the background metric whereby magnetic fields can be stimulated
through the growth of scalar metric perturbations during metric preheating.

</DOC>
<DOC>
<DOCNO> 70812 </DOCNO>
Magnetic Fields in the Early Universe


  This review concerns the origin and the possible effects of magnetic fields
in the early Universe. We start by providing to the reader with a short
overview of the current state of art of observations of cosmic magnetic fields.
We then illustrate the arguments in favour of a primordial origin of magnetic
fields in the galaxies and in the clusters of galaxies. We argue that the most
promising way to test this hypothesis is to look for possible imprints of
magnetic fields on the temperature and polarization anisotropies of the cosmic
microwave background radiation (CMBR). With this purpose in mind, we provide a
review of the most relevant effects of magnetic fields on the CMBR. A long
chapter of this review is dedicated to particle physics inspired models which
predict the generation of magnetic fields during the early Universe evolution.
Although it is still unclear if any of these models can really explain the
origin of galactic and intergalactic magnetic fields, we show that interesting
effects may arise anyhow. Among these effects, we discuss the consequences of
strong magnetic fields on the big-bang nucleosynthesis, on the masses and
couplings of the matter constituents, on the electroweak phase transition, and
on the baryon and lepton number violating sphaleron processes. Several
intriguing common aspects, and possible interplay, of magnetogenesis and
baryogenesis are also dicussed.

</DOC>
<DOC>
<DOCNO> 68406 </DOCNO>
CP Violations in Lepton Number Violation Processes and Neutrino


  We examine the constraints on the MNS lepton mixing matrix from the present
and future experimental data of the neutrino oscillation and lepton number
violation processes. We introduce a graphical representation of the CP
violation phases which appear in the lepton number violation processes such as
neutrinoless double beta decay, the $\mu^--e^+$ conversion, and the K decay,
$K^-\to\pi^+\mu^-\mu^-.$ Using this graphical representation, we derive the
constraints on the CP violation phases in the lepton sector.

</DOC>
<DOC>
<DOCNO> 39744 </DOCNO>
Consistent Measurements of alpha_s from Precise Oriented Event Shape


  An updated analysis using about 1.5 million events recorded at $\sqrt{s} =
M_Z$ with the DELPHI detector in 1994 is presented. Eighteen infrared and
collinear safe event shape observables are measured as a function of the polar
angle of the thrust axis. The data are compared to theoretical calculations in
${\cal O} (\alpha_s^2)$ including the event orientation. A combined fit of
$\alpha_s$ and of the renormalization scale $x_{\mu}$ in $\cal O(\alpha_s^2$)
yields an excellent description of the high statistics data.
  The weighted average from 18 observables including quark mass effects and
correlations is $\alpha_s(M_Z^2) = 0.1174 \pm 0.0026$. The final result,
derived from the jet cone energy fraction, the observable with the smallest
theoretical and experimental uncertainty, is $\alpha_s(M_Z^2) = 0.1180 \pm
0.0006 (exp.) \pm 0.0013 (hadr.) \pm 0.0008 (scale) \pm 0.0007 (mass)$.
  Further studies include an $\alpha_s$ determination using theoretical
predictions in the next-to-leading log approximation (NLLA), matched NLLA and
$\cal O(\alpha_s^2$) predictions as well as theoretically motivated optimized
scale setting methods. The influence of higher order contributions was also
investigated by using the method of Pad\'{e} approximants. Average $\alpha_s$
values derived from the different approaches are in good agreement.

</DOC>
<DOC>
<DOCNO> 101987 </DOCNO>
Quasi-actions on trees I, Bounded valence


  Given a bounded valence, bushy tree T, we prove that any quasi-action of a
group G on T is quasiconjugate to an action of G on another bounded valence,
bushy tree T'. This theorem has many applications: quasi-isometric rigidity for
fundamental groups of finite, bushy graphs of coarse PD(n) groups for each
fixed n; a generalization to actions on Cantor sets of Sullivan's Theorem about
uniformly quasiconformal actions on the 2-sphere; and a characterization of
locally compact topological groups which contain a virtually free group as a
cocompact lattice. Finally, we give the first examples of two finitely
generated groups which are quasi-isometric and yet which cannot act on the same
proper geodesic metric space, properly discontinuously and cocompactly by
isometries.

</DOC>
<DOC>
<DOCNO> 69371 </DOCNO>
Measuring the Higgs CP Property through Top Quark Pair Production at


  We present a model-independent study of the effects of a neutral Higgs boson
without definite CP-parity in the process $\gamma\gamma \to t\bar{t}$ around
the mass pole of the Higgs boson. Near the resonance pole, the interference
between the Higgs-exchange and the continuum amplitudes can be sizable if the
photon beams are polarized and helicities of the top and anti-top quarks are
measured. Study of these interference effects enables one to determine the CP
property of the Higgs boson completely. An example of the complete
determination is demonstrated in the context of the minimal supersymmetric
standard model.

</DOC>
<DOC>
<DOCNO> 151323 </DOCNO>
Casimir effect for a dilute dielectric ball at finite temperature


  The Casimir effect at finite temperature is investigated for a dilute
dielectric ball; i.e., the relevant internal and free energies are calculated.
The starting point in this study is a rigorous general expression for the
internal energy of a system of noninteracting oscillators in terms of the sum
over the Matsubara frequencies. Summation over the angular momentum values is
accomplished in a closed form by making use of the addition theorem for the
relevant Bessel functions. For removing the divergences the renormalization
procedure is applied that has been developed in the calculation of the
corresponding Casimir energy at zero temperature. The behavior of the
thermodynamic characteristics in the low and high temperature limits is
investigated.

</DOC>
<DOC>
<DOCNO> 11450 </DOCNO>
Critical Behaviour in the Dense Planar NJL Model


  We present results of a Monte Carlo simulation of a 2+1 dimensional Nambu -
Jona-Lasinio model including diquark source terms. A diquark condensate <qq> is
measured as a function of source strength j. In the vacuum phase <qq> vanishes
linearly with j as expected, but simulations in a region with non-zero baryon
density suggest a power-law scaling and hence a critical system for all mu >
mu_c. There is no diquark condensation signalling superfluidity. Comparisons
are drawn with known results in two dimensional theories, and with the
pseudogap phase in cuprate superconductors. We also measure the dispersion
relation E(k) for fermionic excitations, and find results consistent with a
sharp Fermi surface. Any superfluid gap Delta is constrained to be much less
than the constituent quark mass scale Sigma_0.

</DOC>
<DOC>
<DOCNO> 40609 </DOCNO>
FunctionalObjects.h: Using Symbolic Syntax in C++ Programs


  functionalObjects.h allows the C++ programmer performing common mathematical
calculations to use a more symbolic syntax rather than an algorithmic syntax.
This is not as ambitious as a symbolic manipulation program such as
Mathematica; it is more like having the ability to drop a very simple
Mathematica statement into a C++ program.

</DOC>
<DOC>
<DOCNO> 68891 </DOCNO>
Primordial galactic magnetic fields from domain walls at the QCD phase


  We propose a mechanism to generate large-scale magnetic fields with
correlation lengths of 100 kpc. Domain walls with QCD scale internal structure
form and coalesce obtaining Hubble scale correlations and align nucleon spins.
Due to strong CP violation, nucleons in these walls have anomalous electric and
magnetic dipole moments and thus the walls are ferromagnetic. This induces
electromagnetic fields with Hubble size correlations. The same CP violation
also induces a maximal helicity (Chern-Simons) correlated through the Hubble
volume which supports an inverse cascade allowing the initial correlations to
grow to 100 kpc today. We estimate the generated electromagnetic fields in
terms of the QCD parameters and discuss the effects of the resulting fields.

</DOC>
<DOC>
<DOCNO> 85018 </DOCNO>
Hyperfluid - a model of classical matter with hypermomentum


  A variational theory of a continuous medium is developed the elements of
which carry momentum and hypermomentum (hyperfluid). It is shown that the
structure of the sources in metric-affine gravity is predetermined by the
conservation identities and, when using the Weyssenhoff ansatz, these
explicitly yield the hyperfluid currents.

</DOC>
<DOC>
<DOCNO> 14181 </DOCNO>
Consequences of charge imbalance in superconductors within the theory of


  The theory of hole superconductivity proposes that the fundamental asymmetry
between electrons and holes in solids is responsible for superconductivity.
Here we point out a remarkable consequence of this theory: a tendency for
negative charge to be expelled from the bulk of the superconductor towards the
surface. Experimentally observable consequences of this physics are discussed.

</DOC>
<DOC>
<DOCNO> 170620 </DOCNO>
Einselection and Decoherence from an Information Theory Perspective


  We introduce and investigate a simple model of conditional quantum dynamics.
It allows for a discussion of the information-theoretic aspects of quantum
measurements, decoherence, and environment-induced superselection
(einselection).

</DOC>
<DOC>
<DOCNO> 120926 </DOCNO>
The Effect of the (2+1)-Dimensional Gravity in the Spiral Galaxy


  The slowly decreasing rotational velocity of the Milky Way suggests the
existence of the dark matter. One finds that the effect of the dark matter in a
galaxy can be described by a $(2+1)$-dimensional fluid model. The stability
analysis for the corresponding fluid model is discussed in details in this
paper. It is found that the pressure term plays an important role in the
stability of the spiral arms and counteracts the increasing mass of the
observed galaxy as the radial distance increases. When the fluid region ends,
the $ nearly $ constant rotational velocity of the distant stars require no
additional mass if the spatial dimension in the remote region is close to two.
This indicates that the galaxies, we are interested, could be explained by a
$(2+1)$-dimensional model. Possible implications are also discussed in this
paper.

</DOC>
<DOC>
<DOCNO> 8933 </DOCNO>
Thermodynamics of Spin S = 1/2 Antiferromagnetic Uniform and


  The magnetic susceptibility chi and specific heat C versus temperature T of
the spin-1/2 antiferromagnetic alternating-exchange (J1 and J2) Heisenberg
chain are studied for the entire range 0 \leq alpha \leq 1 of the alternation
parameter alpha = J2/J1. For the uniform chain (alpha = 1), detailed
comparisons of the high-accuracy chi(T) and C(T) Bethe ansatz data of Kluemper
and Johnston are made with the asymptotically exact low-T field theory
predictions of Lukyanov. QMC simulations and TMRG calculations of chi(alpha,T)
are presented. From the low-T TMRG data, the spin gap Delta(alpha)/J1 is
extracted for 0.8 \leq alpha \leq 0.995. High accuracy fits to all of the above
numerical data are obtained. We examine in detail the theoretical predictions
of Bulaevskii for chi(alpha,T) and compare them with our results. Our
experimental chi(T) and C(T) data for NaV2O5 single crystals are modeled in
detail. The chi(T) data above the spin dimerization temperature Tc = 34 K are
not in agreement with the prediction for the uniform Heisenberg chain, but can
be explained if there is a moderate ferromagnetic interchain coupling and/or if
J changes with T. By fitting the chi(T) data, we obtain Delta(T = 0) = 103(2)
K, alternation parameter delta(0) = (1 - alpha)/(1 + alpha) = 0.034(6) and
average exchange constant J(0) = 640(80) K. The delta(T) and Delta(T) are
derived from the data. A spin pseudogap with a large magnitude \approx 0.4
Delta(0) is consistently found just above Tc, which decreases with increasing
T. Analysis of our C(T) data indicates that at Tc, at least 77% of the entropy
change due to the transition at Tc and associated order parameter fluctuations
arise from the lattice and/or charge degrees of freedom and less than 23% from
the spin degrees of freedom.

</DOC>
<DOC>
<DOCNO> 39978 </DOCNO>
Extracting |V_{ub}| from the Hadronic Mass Spectrum of Inclusive B


  Following a strategy introduced earlier by the authors, we show that it is
possible to extract |V_{ub}| from the cut hadronic mass spectrum of B decays
without large systematic errors which usually arise from having to model the
Fermi motion of the heavy quark. We present a closed form expression for
|V_{ub}|/|V_{ts}| which is accurate up to corrections of order \alpha_s^2,
\alpha_s \rho, (\Lambda/m_b)^2/\rho, where \rho is the experimental cut
(s_c/m_b^2) on the hadronic mass used to veto charmed decays. Modulo duality
violation errors, which are intrinsic to all inclusive predictions, we estimate
the theoretical error in the extraction to be at the 5% level.

</DOC>
<DOC>
<DOCNO> 11851 </DOCNO>
Superconductivity in the Pseudogap State due to Fluctuations of


  We analyze the anomalies of superconducting state (s and d-wave pairing) in a
simple model of pseudogap state, induced by fluctuations of short - range order
(e.g. antiferromagnetic), based on the model Fermi surface with "hot patches".
We derive a system of recursion relations for Gorkov's equations which take
into account all diagrams of perturbation theory for electron interaction with
fluctuations of short-range order. Then we find superconducting transition
temperature and gap behavior for different values of the pseudogap width and
correlation lengths of short-range order fluctuations. In a similar
approximation we derive the Ginzburg-Landau expansion and study the main
physical characteristics of a superconductor close to the transition
temperature, both as functions of the pseudogap width and correlation length of
fluctuations. Results obtained are in qualitative agreement with a number of
experiments on underdoped HTSC-cuprates.

</DOC>
<DOC>
<DOCNO> 67950 </DOCNO>
The Second Peak: The Dark-Energy Density and the Cosmic Microwave


  Supernova evidence for a negative-pressure dark energy (e.g., cosmological
constant or quintessence) that contributes a fraction $\Omega_\Lambda\simeq0.7$
of closure density has been bolstered by the discrepancy between the total
density, $\Omega_{\rm tot}\simeq1$, suggested by the location of the first peak
in the cosmic microwave background (CMB) power spectrum and the
nonrelativistic-matter density $\Omega_m\simeq0.3$ obtained from dynamical
measurements. Here we show that the impending identification of the location of
the {\it second} peak in the CMB power spectrum will provide an immediate and
independent probe of the dark-energy density. As an aside, we show how the
measured height of the first peak probably already points toward a low matter
density and places upper limits to the reionization optical depth and
gravitational-wave amplitude.

</DOC>
<DOC>
<DOCNO> 102146 </DOCNO>
Realcompactness and Banach-Stone theorems


  For realcompact spaces X and Y we give a complete description of the linear
biseparating maps between spaces of vector-valued continuous functions on X and
Y, where special attention is paid to spaces of vector-valued bounded
continuous functions. These results are applied to describe the linear
isometries between spaces of vector-valued bounded continuous and uniformly
continuous functions.

</DOC>
<DOC>
<DOCNO> 174472 </DOCNO>
Photofission of heavy nuclei at energies up to 4 GeV


  Total photofission cross sections for 238U, 235U, 233U, 237Np, 232Th, and
natPb have been measured simultaneously, using tagged photons in the energy
range Egamma=0.17-3.84 GeV. This was the first experiment performed using the
Photon Tagging Facility in Hall B at Jefferson Lab. Our results show that the
photofission cross section for 238U relative to that for 237Np is about 80%,
implying the presence of important processes that compete with fission. We also
observe that the relative photofission cross sections do not depend strongly on
the incident photon energy over this entire energy range. If we assume that for
237Np the photofission probability is equal to unity, we observe a significant
shadowing effect starting below 1.5 GeV.

</DOC>
<DOC>
<DOCNO> 102078 </DOCNO>
Homotopy types of homeomorphism groups of noncompact 2-manifolds


  Suppose M is a noncompact connected PL 2-manifold and let H(M)_0 denote the
identity component of the homeomorphism group of M with the compact-open
topology. In this paper we classify the homotopy type of H(M)_0 by showing that
{\cal H}(M)_0 has the homotopy type of the circle if M is the plane, an open or
half open annulus, or the punctured projective plane. In all other cases we
show that H(M)_0 is homotopically trivial.

</DOC>
<DOC>
<DOCNO> 11443 </DOCNO>
Quantum Interference Mechanism of Cooperative Optical Phenomena in


  In the quantum process of stimulated Raman scattering (SRS), a laser photon
propagating in a resonance medium undergoes multifold conversions into a Stokes
photon and back. The nontrivial ``cooperative'' behavior of the Stokes
component of light transmitted through the medium is proven to be completely
determined by the interference of scattering amplitudes in different
sub-channels of the Stokes channel, which obviously combines all the
sub-channels with an odd number of photon conversions. The theory of
superfluorescence is then derived as the limiting case of the SRS theory.

</DOC>
<DOC>
<DOCNO> 102279 </DOCNO>
3-manifolds which are spacelike slices of flat spacetimes


  We continue work initiated in a 1990 preprint of Mess giving a geometric
parameterization of the moduli space of classical solutions to Einstein's
equations in 2+1 dimensions with cosmological constant 0 or -1 (the case +1 has
been worked out in the interim by the present author). In this paper we make a
first step toward the 3+1-dimensional case by determining exactly which closed
3-manifolds M^3 arise as spacelike slices of flat spacetimes, and by finding
all possible holonomy homomorphisms pi_1(M^3) to ISO(3,1).

</DOC>
<DOC>
<DOCNO> 11353 </DOCNO>
Normal scaling in globally conserved interface-controlled coarsening of


  Globally conserved interface-controlled coarsening of fractal clusters
exhibits dynamic scale invariance and normal scaling. This is demonstrated by a
numerical solution of the Ginzburg-Landau equation with a global conservation
law. The sharp-interface limit of this equation is volume preserving motion by
mean curvature. The scaled form of the correlation function has a power-law
tail accommodating the fractal initial condition. The coarsening length
exhibits normal scaling with time. Finally, shrinking of the fractal clusters
with time is observed. The difference between global and local conservation is
discussed.

</DOC>
<DOC>
<DOCNO> 85196 </DOCNO>
Mass and Spin Renormalization in Lorentz Electrodynamics


  A new, relativistically covariant, massive Lorentz Electrodynamics (LED) is
presented in which the bare particle has a finite positive bare rest mass and
moment of inertia. The particle's electromagnetic self-interaction renormalizes
its mass and spin. Most crucially, the renormalized particle is a soliton:
after any scattering process its rest mass and spin magnitude are dynamically
restored to their pre-scattering values. This guarantees that ``an electron
remains an electron,'' poetically speaking. A renormalization flow study of the
limit of vanishing bare rest mass is conducted for this model. This limit
yields a purely electromagnetic classical field theory with ultra-violet cutoff
at about the electron's Compton wavelength! The renormalized limit model
matches the empirical electron data as orderly as one can hope for at the level
of Lorentz theory. In particular, no superluminal equatorial gyration speeds
occur.

</DOC>
<DOC>
<DOCNO> 118799 </DOCNO>
Gamma-Ray Background from Structure Formation in the Intergalactic


  The universe is filled with a diffuse and isotropic extragalactic background
of gamma-ray radiation, containing roughly equal energy flux per decade in
photon energy between 3 MeV-100 GeV. The origin of this background is one of
the unsolved puzzles in cosmology. Less than a quarter of the gamma-ray flux
can be attributed to unresolved discrete sources, but the remainder appears to
constitute a truly diffuse background whose origin has hitherto been
mysterious. Here we show that the shock waves induced by gravity during the
formation of large-scale structure in the intergalactic medium, produce a
population of highly-relativistic electrons with a maximum Lorentz factor above
10^7. These electrons scatter a small fraction of the microwave background
photons in the present-day universe up to gamma-ray energies, thereby providing
the gamma-ray background. The predicted diffuse flux agrees with the observed
background over more than four decades in photon energy, and implies a mean
cosmological density of baryons which is consistent with Big-Bang
nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 122614 </DOCNO>
Finite temperature amplitudes and reaction rates in Thermofield dynamics


  We propose a method for calculating the reaction rates and transition
amplitudes of generic process taking place in a many body system in
equilibrium. The relationship of the scattering and decay amplitudes as
calculated in Thermo Field Dynamics the conventional techniques is established.
It is shown that in many cases the calculations are relatively easy in TFD.

</DOC>
<DOC>
<DOCNO> 119365 </DOCNO>
The INT Search for Metal-Poor Stars. Spectroscopic Observations and


  With the dual aims of enlarging the list of extremely metal-poor stars
identified in the Galaxy, and boosting the numbers of moderately
metal-deficient stars in directions that sample the rotational properties of
the thick disk, we have used the 2.5m Isaac Newton Telescope and the
Intermediate Dispersion Spectrograph to carry out a survey of brighter
(primarily northern hemisphere) metal-poor candidates selected from the HK
objective-prism/interference-filter survey of Beers and collaborators. Over the
course of only three observing runs (15 nights) we have obtained
medium-resolution (resolving power ~ 2000) spectra for 1203 objects (V ~
11-15). Spectral absorption-line indices and radial velocities have been
measured for all of the candidates. Metallicities, quantified by [Fe/H], and
intrinsic (B-V)o colors have been estimated for 731 stars with effective
temperatures cooler than roughly 6500 K, making use of artificial neural
networks (ANNs), trained with spectral indices. We show that this method
performs as well as a previously explored Ca II K calibration technique, yet it
presents some practical advantages. Among the candidates in our sample, we
identify 195 stars with [Fe/H] <= -1.0, 67 stars with [Fe/H] <= -2.0, and 12
new stars with [Fe/H] <= -3.0. Although the EFECTIVE YIELD of metal-poor stars
in our sample is not as large as previous HK survey follow-up programs, the
rate of discovery per unit of telescope time is quite high.

</DOC>
<DOC>
<DOCNO> 121211 </DOCNO>
Search for Millisecond Periodicities in Type I X-ray Bursts of the Rapid


  We have searched the rising portion of type I X-ray bursts observed from the
Rapid Burster with the Rossi X-ray Timing Explorer for the presence of
periodicities. The 95 per cent confidence upper limit on the average
root-mean-square variation of near coherent pulsations with a width of <1 Hz
(in 60--2048 Hz) during the first second of the bursts is <8.8 per cent. We
find a possible detection (>98 per cent significance) at 306.5 Hz.

</DOC>
<DOC>
<DOCNO> 99420 </DOCNO>
Infinitesimal K-theory


  In this paper we study the fiber F of the rational Jones-Goodwillie character
$$ F:=\hofiber(ch:K^\rat(A)@>>>HN^\rat(A)) $$ going from K-theory to negative
cyclic homology of associative rings. We describe this fiber F in terms of
sheaf cohomology. We prove that, for $n\ge 1$, there is an isomorphism: $$
\pi_n(F)\cong H^{-n}_{inf}(A,K^\rat) $$ between the homotopy of the fiber and
the hypercohomology groups of $K^\rat$ on a non-commutative version of
Grothendieck's infinitesimal site.

</DOC>
<DOC>
<DOCNO> 11979 </DOCNO>
Direct Observation and Anisotropy of the Contribution of Gap nodes in


  The specific heat due to line nodes in the superconducting gap of YBa2Cu3O7
has been obscured up to now by magnetic terms of extrinsic origin, even for
high quality crystals. We report the specific heat of a new single crystal
grown in a non-corrosive BaZrO3 crucible, for which paramagnetic terms are
reduced to less than one spin-1/2 center for 20'000 Cu atoms. The contribution
of line nodes shows up directly in the difference C(B,T) - C(0,T) at fixed
temperatures (T < 5 K) as a function of the magnetic field parallel to the
c-axis (B<=14 T). These data illustrate the smooth crossover from C propotional
to T^2 at low fields to C propotional to TB^1/2 at high fields, and provide new
values for gap parameters which are quantitatively consistent with tunneling
spectroscopy and thermal conductivity in the framework of dx^2-y^2 pairing
symmetry. Data for B along the nodal and antinodal directions in the ab-plane
are also provided. The in-plane anisotropy predicted in the clean limit is not
observed.

</DOC>
<DOC>
<DOCNO> 99307 </DOCNO>
Subexponential groups in 4-manifold topology


  We present a new, more elementary proof of the Freedman-Teichner result that
the geometric classification techniques (surgery, s-cobordism, and
pseudoisotopy) hold for topological 4-manifolds with groups of subexponential
growth. In an appendix Freedman and Teichner give a correction to their
original proof, and reformulate the growth estimates in terms of coarse
geometry.

</DOC>
<DOC>
<DOCNO> 9943 </DOCNO>
Macroscopic resonant tunneling of magnetic flux


  We have developed a quantitative theory of resonant tunneling of magnetic
flux between discrete macroscopically distinct quantum states in SQUID systems.
The theory is based on the standard density-matrix approach. Its new elements
include the discussion of the two different relaxation mechanisms that exist
for the double-well potential, and description of the ``photon-assisted''
tunneling driven by external rf radiation. It is shown that in the case of
coherent flux dynamics, rf radiation should lead to splitting of the peaks of
resonant flux tunneling, indicating that the resonant tunneling is a convenient
tool for studying macroscopic quantum coherence of flux.

</DOC>
<DOC>
<DOCNO> 12892 </DOCNO>
Non-perturbative effective field theory for two-leg antiferromagnetic


  We study the long wavelength limit of a spin 1/2 Heisenberg antiferromagnetic
two-leg ladder, treating the interchain coupling in a non-perturbative way. We
perform a mean field analysis and then include exactly the fluctuations. This
allows for a discussion of the phase diagram of the system and provides an
effective field theory for the low energy excitations. The coset fermionic
Lagrangian obtained corresponds to a perturbed SU(4)_1/U(1) Conformal Field
Theory (CFT). This effective theory is naturally embedded in a SU(2)_2 x Z_2
CFT, where perturbations are easily identified in terms of conformal operators
in the two sectors. Crossed and zig-zag ladders are also discussed using the
same approach.

</DOC>
<DOC>
<DOCNO> 119010 </DOCNO>
Galactic Gamma-Ray Background Radiation from Supernova Remnants


  The contribution of the Source Cosmic Rays (SCRs), confined in Supernova
Remnants, to the diffuse high energy \gr emission above 1 GeV from the Galactic
disk is studied. \grs produced by the SCRs have a much harder spectrum compared
with those generated by the Galactic Cosmic Rays which occupy a much larger
residence volume uniformly. SCRs contribute less than 10% at GeV energies and
become dominant at \gr energies above 100 GeV. The contributions from
$\pi^0$-decay and Inverse Compton \grs have comparable magnitude and spectral
shape, whereas the Bremsstrahlung component is negligible. At TeV energies the
contribution from SCRs increases the expected diffuse \gr flux almost by an
order of magnitude. It is shown that for the inner Galaxy the discrepancy
between the observed diffuse intensity and previous model predictions at
energies above a few GeV can be attributed to the SCR contribution.

</DOC>
<DOC>
<DOCNO> 99338 </DOCNO>
The Kronecker product of Schur functions indexed by two-row shapes or


  The Kronecker product of two Schur functions $s_{\mu}$ and $s_{\nu}$, denoted
by $s_{\mu}*s_{\nu}$, is the Frobenius characteristic of the tensor product of
the irreducible representations of the symmetric group corresponding to the
partitions $\mu$ and $\nu$. The coefficient of $s_{\lambda}$ in this product is
denoted by $\gamma^{\lambda}_{{\mu}{\nu}}$, and corresponds to the multiplicity
of the irreducible character $\chi^{\lambda}$ in $\chi^{\mu}\chi^{\nu}.$
  We use Sergeev's Formula for a Schur function of a difference of two
alphabets and the comultiplication expansion for $s_{\lambda}[XY]$ to find
closed formulas for the Kronecker coefficients $\gamma^{\lambda}_{{\mu}{\nu}}$
when $\lambda$ is an arbitrary shape and $\mu$ and $\nu$ are hook shapes or
two-row shapes.
  Remmel \cite{Re1, Re2} and Remmel and Whitehead \cite{Re-Wh} derived some
closed formulas for the Kronecker product of Schur functions indexed by two-row
shapes or hook shapes using a different approach. We believe that the approach
of this paper is more natural. The formulas obtained are simpler and reflect
the symmetry of the Kronecker product.

</DOC>
<DOC>
<DOCNO> 119325 </DOCNO>
Zinc as a tracer of metallicity evolution of Damped Lyman alpha systems


  Zinc is a good indicator of metallicity in Damped Lyman alpha (DLA) systems
because it is almost unaffected by dust depletion. However, the use of zinc as
a tracer of metallicity evolution has been hampered by the difficulty of
detecting the Zn II resonance lines at high redshift. The measurement of zinc
abundance in a DLA system at z_abs > 3 obtained by means of the UVES
spectrograph at the VLT prompted us to re-analyse the full sample of zinc
abundances present in the literature to search for a metallicity-redshift
relation in DLA systems. The study of the metallicities of individual systems
shows evidence for an anti-correlation between [Zn/H] and redshift supported by
different types of statistical tools. The zinc metallicity decreases by -0.3
+/- 0.1 dex per unit redshift interval in the range 0.5 <~ z_abs <~ 3.5. This
rate is in good agreement with that found by Savaglio, Panagia & Stiavelli
(2000) in their recent study of DLA abundances corrected for dust depletion.
The present result does not require a knowledge of the dust depletion
pattern(s) in DLA systems. On the other hand, the analysis of the
column-density weighted metallicity of the sample, <Z>, does not show a clear
evidence for redshift evolution, consistent with previous studies of zinc
abundances. We propose that the apparent lack of evolution of <Z> is due to the
combination of selection bias effects together with the extreme sensitivity of
<Z> to low-number statistics.

</DOC>
<DOC>
<DOCNO> 12392 </DOCNO>
Quantum brownian motion on a triangular lattice and c=2 boundary


  We study a single particle diffusing on a triangular lattice and interacting
with a heat bath, using boundary conformal field theory (CFT) and exact
integrability techniques. We derive a correspondence between the phase diagram
of this problem and that recently obtained for the 2 dimensional 3-state Potts
model with a boundary. Exact results are obtained on phases with intermediate
mobilities. These correspond to non-trivial boundary states in a conformal
field theory with 2 free bosons which we explicitly construct for the first
time. These conformally invariant boundary conditions are not simply products
of Dirichlet and Neumann ones and unlike those trivial boundary conditions, are
not invariant under a Heisenberg algebra.

</DOC>
<DOC>
<DOCNO> 83356 </DOCNO>
Phutball Endgames are Hard


  We show that, in John Conway's board game Phutball (or Philosopher's
Football), it is NP-complete to determine whether the current player has a move
that immediately wins the game. In contrast, the similar problems of
determining whether there is an immediately winning move in checkers, or a move
that kings a man, are both solvable in polynomial time.

</DOC>
<DOC>
<DOCNO> 118454 </DOCNO>
Evidence of Multiple r-Process Sites in the Early Galaxy: New


  First results are reported of a new abundance study of neutron-capture
elements in the ultra-metal-poor (UMP; [Fe/H] = -3.1) halo field giant star CS
22892-052. Using new high resolution, high signal-to-noise spectra, abundances
of more than 30 neutron-capture elements (Z>30) have been determined. Six
elements in the 40<Z<56 domain (Nb, Ru, Rh, Pd, Ag and Cd) have been detected
for the first time in a UMP star. Abundances are also derived for three of the
heaviest stable elements (Os, Ir, and Pb). A second transition of thorium,
Th{4086}, confirms the abundance deduced from the standard Th{4019} line, and
an upper limit to the abundance of uranium is established from the absence of
the U{3859} line. As found in previous studies, the abundances of the heavier
(Z>=56) stable neutron-capture elements in CS 22892-052 match well the scaled
solar system r-process abundance distribution. From the observed Th abundance,
an average age of ~= 16 +/- 4 Gyr is derived for cs22892-052, consistent with
the lower age limit of ~= 11 Gyr derived from the upper limit on the U
abundance. The concordance of scaled solar r-process and CS 22892-052
abundances breaks down for the lighter neutron-capture elements, supporting
previous suggestions that different r-process production sites are responsible
for lighter and heavier neutron-capture elements.

</DOC>
<DOC>
<DOCNO> 100838 </DOCNO>
Approximating Spectral invariants of Harper operators on graphs


  We study Harper operators and the closely related discrete magnetic
Laplacians (DML) on a graph with a free action of a discrete group, as defined
by Sunada. A main result in this paper is that the spectral density function of
DMLs associated to rational weight functions on graphs with a free action of an
amenable discrete group, can be approximated by the average spectral density
function of the DMLs on a regular exhaustion, with either Dirichlet or Neumann
boundary conditions. This then gives a criterion for the existence of gaps in
the spectrum of the DML, as well as other interesting spectral properties of
such DMLs. The technique used incorporates some results of algebraic number
theory.

</DOC>
<DOC>
<DOCNO> 169618 </DOCNO>
Daylight quantum key distribution over 1.6 km


  Quantum key distribution (QKD) has been demonstrated over a point-to-point
$\sim1.6$-km atmospheric optical path in full daylight. This record
transmission distance brings QKD a step closer to surface-to-satellite and
other long-distance applications.

</DOC>
<DOC>
<DOCNO> 121887 </DOCNO>
The effect of magnetic fields on the mass determination of clusters of


  We test the effects of magnetic fields on the mass determination of galaxy
clusters with the X-ray method. As this method takes into account only thermal
pressure, additional non-thermal pressure support, e.g. caused by a magnetic
field, can result in an underestimation of the mass. SPH models of galaxy
clusters including magnetic fields of various strengths in two different
cosmologies are used for the test. We compare the true mass of the model
clusters with the mass determined from simulated X-ray images of the same
models. The effect of the magnetic field on the mass in relaxed clusters is
found to be negligible compared to other uncertainties, even at small radii,
where the strongest effects are expected. However in one model, in which the
cluster is in the process of merging, we find an effect of up to a factor of 2
caused by the magnetic field. In relaxed clusters the mass estimate, averaged
over many models, is at most 15% smaller in models with relatively high
magnetic field of $2\mu$G compared to models without a magnetic field with a
small dependence on the cosmology chosen. Therefore we conclude that the
presence of a magnetic field cannot be responsible for the discrepancies of a
factor of 2-3 found between X-ray and lensing mass in the central regions of
relaxed clusters.

</DOC>
<DOC>
<DOCNO> 122166 </DOCNO>
Ultra-High-Density Molecular Core and Warped Nuclear Disk in the Deep


  We have performed high-resolution synthesis observations of the 12CO (J=1-0)
line emission from the radio lobe edge-on spiral NGC 3079 using a 7-element
mm-wave interferometer at Nobeyama, which consisted of the 45-m telescope and
6-element Array. The molecular nuclear disk (NMD) of 750 pc radius is found to
be inclined by 20 degrees from the optical disk, and the NMD has spiral arms.
An ultra-high-density molecular core (UHC) was found at the nucleus. The
gaseous mass of the UHC within 125 pc radius is as large as about 3 x 10^8
Msun, an order of magnitude more massive than that in the same area of the
Galactic Center, and the mean density is as high as approximately 3 x 10^3 H2
cm^-3. A position-velocity diagram along the major axis indicates that the
rotation curve starts at a finite velocity exceeding 300 \kms already from the
nucleus. The surface mass density in the central region is estimated to be as
high as about 10^5 Msun pc^-2, producing a very deep gravitational potential.
We argue that the very large differential rotation in such a deep potential
will keep the UHC gravitationally stable from current star formation.

</DOC>
<DOC>
<DOCNO> 118304 </DOCNO>
BeppoSAX spectrum of GRB971214: evidence of a substantial energy output


  We report the X/gamma-ray spectrum of GRB971214 and of its afterglow. The
afterglow was measured few hours after the main event and for an elapsed time
of more than two days. The measure of this GRB and afterglow is relevant due to
its extreme, cosmological distance (z=3.42). The prompt event shows a hard
photon spectrum, consistent with a broken power law with photon indices
Gamma_X~0.1 below ~20 keV and Gamma_g~1.3 above 60 keV. The afterglow spectrum,
measured with the MECS and LECS BeppoSAX telescopes, is consistent with a power
law with spectral photon index Gamma=1.6. Within the statistical accuracy of
our measure no spectral evolution is detected during the observation of the
afterglow. When integrated during the time span covered by BeppoSAX
observations, the power in the afterglow emission, even with very conservative
assumptions, is at least comparable with the power in the main event. The
IR-to-X rays broad band spectrum is also presented, collecting data from the
literature and adding them to the BeppoSAX measure. It shows that the
predictions from synchrotron emission models is qualitatively confirmed. The
BeppoSAX measurement of the X and gamma ray spectrum of this GRB/afterglow is
discussed in the framework of current theoretical models.

</DOC>
<DOC>
<DOCNO> 80732 </DOCNO>
Deconfinement transition and string tensions in SU(4) Yang-Mills Theory


  We present results from numerical lattice calculations of SU(4) Yang-Mills
theory. This work has two goals: to determine the order of the finite
temperature deconfinement transition on an $N_t = 6$ lattice and to study the
string tensions between static charges in the irreducible representations of
SU(4). Motivated by Pisarski and Tytgat's argument that a second-order
SU($\infty$) deconfinement transition would explain some features of the SU(3)
and QCD transitions, we confirm older results on a coarser, $N_t = 4$, lattice.
We see a clear two-phase coexistence signal, characteristic of a first-order
transition, at $8/g^2 = 10.79$ on a $6\times 20^3$ lattice, on which we also
compute a latent heat of $\Delta\epsilon\approx 0.6 \epsilon_{SB}$. Computing
Polyakov loop correlation functions we calculate the string tension at finite
temperature in the confined phase between fundamental charges, $\sigma_1$,
between diquark charges, $\sigma_2$, and between adjoint charges $\sigma_4$. We
find that $1 < \sigma_2/\sigma_1 < 2$, and our result for the adjoint string
tension $\sigma_4$ is consistent with string breaking.

</DOC>
<DOC>
<DOCNO> 14131 </DOCNO>
On the solution of the modified Ginzburg-Landau type equation for


  We perform an analytical and numerical study of the crossover from the
Josephson effect to the bulk superconducting flow for two identical
one-dimensional superconductors, co-existing with a layer of normal material.
  A generalized Ginzburg-Landau (GL) model, proposed by S.J. Chapman, Q. Du and
M.D. Gunzburger was used in modeling the whole structure. When the thickness of
the normal layer is very small, the introduction of three effective potentials
of specified strength leads to an exact analytical solution of the modified
stationary GL equation.
  The resulting current density-phase offset relation is analyzed numerically.
We show that the critical Josephson current density corresponds to a
bifurcation of the solutions of the nonlinear boundary value problem coupled
with the modified GL-equation. The influence of the second term in the
Fourier-decomposition of the supercurrent density-phase relation is also
investigated.
  We derive also a simple analytical formula for the critical Josephson
current.

</DOC>
<DOC>
<DOCNO> 69458 </DOCNO>
Charmonium + Light Hadron Cross Sections


  In this contribution we summarize experimental information and theoretical
results for the dissociation cross sections of charmonium by light hadrons.
Theoretical predictions for these RHIC-related processes differ by orders of
magnitude over the physically relevant energy range. The results found by the
author and collaborators using a constituent interchange model, which predicts
cross sections in the mb region near threshold, are discussed in more detail.

</DOC>
<DOC>
<DOCNO> 120814 </DOCNO>
A weak turbulence theory for incompressible MHD


  We derive a weak turbulence formalism for incompressible MHD. Three-wave
interactions lead to a system of kinetic equations for the spectral densities
of energy and helicity. We find energy spectra solution of the kinetic
equations. The constants of the spectra are computed exactly and found to
depend on the amount of correlation between the velocity and the magnetic
field. Comparison with several numerical simulations and models is also made.

</DOC>
<DOC>
<DOCNO> 69271 </DOCNO>
Off-Forward Parton Distributions in 1+1 Dimensional QCD


  We use two-dimensional QCD as a toy laboratory to study off-forward parton
distributions (OFPDs) in a covariant field theory. Exact expressions (to
leading order in $1/N_C$) are presented for OFPDs in this model and are
evaluated for some specific numerical examples. Special emphasis is put on
comparing the $x>\zeta$ and $x<\zeta$ regimes as well as on analyzing the
implications for the light-cone description of form factors.

</DOC>
<DOC>
<DOCNO> 99414 </DOCNO>
Pinching, Pontrjagin classes, and negatively curved vector bundles


  We prove several finiteness results for the class $M_{a,b,G,n}$ of
$n$-manifolds that have fundamental groups isomorphic to $G$ and that can be
given complete Riemannian metrics of sectional curvatures within $[a,b]$ where
$a\le b<0$. In particular, if $M$ is a closed negatively curved manifold of
dimension at least three, then only finitely many manifolds in the class
$M_{a,b,\pi_1(M), n}$ are total spaces of vector bundles over $M$. Furthermore,
given a word-hyperbolic group $G$ and an integer $n$ there exists a positive
$\epsilon=\epsilon(n,G)$ such that the tangent bundle of any manifold in the
class $M_{-1-\epsilon, -1, G, n}$ has zero rational Pontrjagin classes.

</DOC>
<DOC>
<DOCNO> 100484 </DOCNO>
Good representations and solvable groups


  We give a characterization of connected solvable groups in terms of the
existence of representations with certain geometric properties. The existence
of such representations for the group of upper triangular matrices played an
important role in the proof of the authors' equivariant Riemann-Roch theorem.

</DOC>
<DOC>
<DOCNO> 117766 </DOCNO>
High-resolution radio observations of Seyfert galaxies in the extended


  We present 8.4 GHz VLA A-configuration observations of 87 sources from the
mid-infrared-selected AGN sample of Rush et al (1993). These 0.25 arcsec
resolution observations allow elongated radio structures tens of parsecs in
size to be resolved and enable radio components smaller than 3.5 arcsec to be
isolated from diffuse galactic disc emission. When combined with previous data,
matched radio observations covering ninety percent of the sample have been
collected and these represent the largest sub-arcsecond-resolution radio
imaging survey of a homogeneously-selected sample of Seyfert galaxies to date.
We use our observations to identify 5 radio-loud AGN in the sample. The nature
of the radio emission from Seyfert nuclei will be discussed in subsequent
papers.

</DOC>
<DOC>
<DOCNO> 151609 </DOCNO>
Holographic Renormalization Group with Fermions and Form Fields


  We find the Holographic Renormalization Group equations for the holographic
duals of generic gravity theories coupled to form fields and spin-1/2 fermions.
Using Hamilton-Jacobi theory we discuss the structure of Ward identities,
anomalies, and the recursive equations for determining the divergent terms of
the generating functional. In particular, the Ward identity associated to
diffeomorphism invariance contains an anomalous contribution that, however, can
be solved either by a suitable counter term or by imposing a condition on the
boundary fields. Consistency conditions for the existence of the dual arise, if
one requires that a Callan-Symanzik type equation follows from the Hamiltonian
constraint. Under mild assumptions we are able to find a class of solutions to
the constraint equations. The structure of the fermionic phase space and
constraints is treated extensively for any dimension and signature.

</DOC>
<DOC>
<DOCNO> 13009 </DOCNO>
Unusual Heavy Electron State in the Filled Skutterudite PrFe$_4$P$_{12}$


  We have succeeded in observing the de Haas-van Alphen effect in the filled
skutterudite PrFe$_4$P$_{12}$, which was reported to exhibit various unusual
transport and thermal properties. The cyclotron effective mass $m^{\rm
\ast}_{\rm c}$ is found to be enormously enhanced compared to a reference
compound LaFe$_4$P$_{12}$. The heaviest mass of $m^{\rm \ast}_{\rm c}=81~{\it
m}_{\rm 0}$ indicates a record value in all the Pr-based compounds, and the
mass decreases considerably with increasing field. Furthermore, the Fermi
surface topology is found to be different from that in LaFe$_4$P$_{12}$,
unexpected for the localized 4$f$-electron system.

</DOC>
<DOC>
<DOCNO> 83160 </DOCNO>
Specifying and Implementing Security Policies Using LaSCO, the Language


  In this dissertation, we present LaSCO, the Language for Security Constraints
on Objects, a new approach to expressing security policies using policy graphs
and present a method for enforcing policies so expressed. Other approaches for
stating security policies fall short of what is desirable with respect to
either policy clarity, executability, or the precision with which a policy may
be expressed. However, LaSCO is designed to have those three desirable
properties of a security policy language as well as: relevance for many
different systems, statement of policies at an appropriate level of detail,
user friendliness for both casual and expert users, and amenability to formal
reasoning. In LaSCO, the constraints of a policy are stated as directed graphs
annotated with expressions describing the situation under which the policy
applies and what the requirement is. LaSCO may be used for such diverse
applications as executing programs, file systems, operating systems,
distributed systems, and networks.
  Formal operational semantics have been defined for LaSCO. An architecture for
implementing LaSCO on any system, is presented along with an implementation of
the system-independent portion in Perl. Using this, we have implemented LaSCO
for Java programs, preventing Java programs from violating policy. A GUI to
facilitate writing policies is provided. We have studied applying LaSCO to a
network as viewed by GrIDS, a distributed intrusion detection system for large
networks, and propose a design. We conclude that LaSCO has characteristics that
enable its use on different types of systems throughout the process of
precisely expressing a policy, understanding the implications of a policy, and
implementing it on a system.

</DOC>
<DOC>
<DOCNO> 80690 </DOCNO>
Green's Function Monte Carlo study of SU(3) lattice gauge theory in


  A `forward walking' Green's Function Monte Carlo algorithm is used to obtain
expectation values for SU(3) lattice Yang-Mills theory in (3+1) dimensions. The
ground state energy and Wilson loops are calculated, and the finite-size
scaling behaviour is explored. Crude estimates of the string tension are
derived, which agree with previous results at intermediate couplings; but more
accurate results for larger loops will be required to establish scaling
behaviour at weak coupling.

</DOC>
<DOC>
<DOCNO> 119668 </DOCNO>
Kinematics of young stars (I): Local irregularities


  The local velocity field of young stars is dominated by the galactic
rotation, the kinematics of the Gould Belt and the nearest OB associations and
open clusters, and the kinematics of the spiral structure. We re-examined here
this local velocity field by using a large sample of nearby O and B stars from
the Hipparcos Catalogue. The high quality astrometric data are complemented
with a careful compilation of radial velocities and Str\"omgren photometry,
which allows individual photometric distances and ages to be derived. The Gould
Belt extends up to 600 pc from the Sun with an inclination with respect to the
galactic plane of $i_{\mathrm{G}} = 16$-$22\degr$ and the ascending node placed
at $\Omega_{\mathrm{G}} = 275$-$295\degr$. Approximately 60% of the stars
younger than 60 Myr belong to this structure. The values found for the Oort
constants when different samples selected by age or distance were used allowed
us to interpret the systematic trends observed as signatures induced by the
kinematic behaviour of the Gould Belt. The contribution of Sco-Cen and Ori OB1
complexes in the characterization of the expansion of the Gould Belt system is
also discussed. We found that a positive $K$-term remains when these aggregates
are excluded. From the kinematic behaviour of the stars and their spatial
distribution we derive an age for the Gould Belt system in the interval 30-60
Myr.

</DOC>
<DOC>
<DOCNO> 80731 </DOCNO>
Suppressing monopoles and vortices : A possibly smoother approach to


  Suppressing monopoles and vortices by introducing large chemical potentials
for them in the Wilson action for the SU(2) lattice gauge theory, we study the
nature of the deconfinement phase transition on N_\sigma^3 \times N_\tau
lattices for N_\tau = 4, 5, 6 and 8 and N_\sigma = 8--16. Using finite size
scaling theory, we obtain \omega = 1.93 \pm 0.03 for N_\tau = 4, in excellent
agreement with universality. Corresponding determinations for the N_\tau = 5
and 6 lattices are also found to be in very good agreement with this estimate.
The critical couplings for N_\tau= 4, 5, 6 and 8 lattices exhibit large shifts
towards the strong coupling region when compared with the usual Wilson action,
and suggest a lot smoother approach to scaling.

</DOC>
<DOC>
<DOCNO> 71837 </DOCNO>
Gravitino creation by an oscillating scalar field


  This paper has been withdrawn because the analytic estimates are not
confirmed by the numerical calculation of Nilles, Peloso and Sorbo
(hep-ph/0102264 and hep-th/0103202).

</DOC>
<DOC>
<DOCNO> 101879 </DOCNO>
Torus actions, combinatorial topology and homological algebra


  The paper surveys some new results and open problems connected with such
fundamental combinatorial concepts as polytopes, simplicial complexes, cubical
complexes, and subspace arrangements. Particular attention is paid to the case
of simplicial and cubical subdivisions of manifolds and, especially, spheres.
We describe important constructions which allow to study all these
combinatorial objects by means of methods of commutative and homological
algebra. The proposed approach to combinatorial problems relies on the theory
of moment-angle complexes, currently being developed by the authors. The theory
centres around the construction that assigns to each simplicial complex $K$
with $m$ vertices a $T^m$-space $\zk$ with a special bigraded cellular
decomposition. In the framework of this theory, the well-known non-singular
toric varieties arise as orbit spaces of maximally free actions of subtori on
moment-angle complexes corresponding to simplicial spheres. We express
different invariants of simplicial complexes and related
combinatorial-geometrical objects in terms of the bigraded cohomology rings of
the corresponding moment-angle complexes. Finally, we show that the new
relationships between combinatorics, geometry and topology result in solutions
to some well-known topological problems.

</DOC>
<DOC>
<DOCNO> 10496 </DOCNO>
Exact solutions of the Lawrence-Doniach model for layered


  We solve the problem of exact minimization of the Lawrence-Doniach (LD)
free-energy functional in parallel magnetic fields. We consider both the
infinite in the layering direction case (the infinite LD model) and the finite
one (the finite LD model). We prove that, contrary to a prevailing view, the
infinite LD model does not admit solutions in the form of isolated Josephson
vortices. For the infinite LD model, we derive a closed, self-consistent system
of mean-field equations involving only two variables. Exact solutions to these
equations prove simultaneous penetration of Josephson vortices into all the
barriers, accompanied by oscillations and jumps of the magnetization, and yield
a completely new expression for the lower critical field. Moreover, the
obtained equations allow us to make self-consistent refinements on such
well-known results as the Meissner state, Fraunhofer oscillations of the
critical Josephson current, the upper critical field, and the vortex solution
of Theodorakis [S. Theodorakis, Phys. Rev. B, v. 42, 10172 (1990)]. Our
consideration of the finite LD model illuminates the role of the boundary
effect. In contrast to the infinite case, an explicit analytical solution to
the Maxwell equations of the finite case does not preclude the existence of
localized Josephson vortex configurations. By the use of this solution, we
obtain a self-consistent description of the Meissner state. Finally, we discuss
some theoretical and experimental implications.

</DOC>
<DOC>
<DOCNO> 69284 </DOCNO>
Quintessence models in Supergravity


  Scalar field models of quintessence typically require that the expectation
value of the field today is of order the Planck mass, if we want them to
explain the observed acceleration of the Universe. This suggests that we should
be considering models in the context of supergravity. We discuss a particular
class of supergravity models and analyze their behavior under different choices
of the Kahler metric.

</DOC>
<DOC>
<DOCNO> 120750 </DOCNO>
The statistics of wide-separation lensed quasars


  The absence of any wide-separation gravitational lenses in the Large Bright
Quasar Survey is used to place limits on the population of cluster-sized halos
in the universe, and hence constrain a number of cosmological parameters. The
results agree with previous investigations in strongly ruling out the standard
cold dark matter model but they are consistent with low-density universes in
which the primordial fluctuation spectrum matches both cluster abundances and
cosmic microwave background measurements. These conclusions are essentially
independent of the cosmological constant, which is in stark contrast to the
statistics of galaxy lenses. The constraints presented here are nullified if
clusters have core radii of more than 10 kpc, but are free of a number of
potential systematic errors, due to the homogeneity of the data.

</DOC>
<DOC>
<DOCNO> 80820 </DOCNO>
High Temperature QCD and Dimensional Reduction


  In this talk I will first give a short discussion of some lattice results for
QCD at finite temperature. I will then describe in some detail the technique of
dimensional reduction, which in principle is a powerful technique to obtain
results on the long distance properties of the quark-gluon plasma. Finally I
will describe some new results, which test the technique in a simpler model,
namely three dimensional gauge theory.

</DOC>
<DOC>
<DOCNO> 118281 </DOCNO>
On The Reddening in X-ray Absorbed Seyfert 1 Galaxies


  There are several Seyfert galaxies for which there is a discrepancy between
the small column of neutral hydrogen deduced from X-ray observations and the
much greater column derived from the reddening of the optical/UV emission lines
and continuum. The standard paradigm has the dust within the highly ionized gas
which produces O~VII and O~VIII absorption edges (i.e., a ``dusty warm
absorber''). We present an alternative model in which the dust exists in a
component of gas in which hydrogen has been stripped, but which is at too low
an ionization state to possess significant columns of O~VII and O~VIII (i.e, a
``lukewarm absorber''). The lukewarm absorber is at sufficient radial distance
to encompass much of the narrow emission-line region, and thus accounts for the
narrow-line reddening, unlike the dusty warm absorber. We test the model by
using a combination of photoionization models and absorption edge fits to
analyze the combined ROSAT/ASCA dataset for the Seyfert 1.5 galaxy, NGC 3227.
We show that the data are well fit by a combination of the lukewarm absorber
and a more highly ionized component similar to that suggested in earlier
studies. We predict that the lukewarm absorber will produce strong UV
absorption lines of N V, C IV, Si IV and Mg II. Finally, these results
illustrate that singly ionized helium is an important, and often overlooked,
source of opacity in the soft X-ray band (100 - 500 eV).

</DOC>
<DOC>
<DOCNO> 70843 </DOCNO>
On the Stewart-Lyth Inverse Problem


  In this paper the Stewart-Lyth inverse problem is rewritten using the
comoving scales as the basic parameter. It is shown that some information on
the inflaton potential can be obtained from observations taking into account
only the scalar power spectrum.

</DOC>
<DOC>
<DOCNO> 101939 </DOCNO>
Special Algebraic Structures


  New notions are introduced in algebra in order to better study the
congruences in number theory. For example, the <special semigroups> makes an
important such contribution.

</DOC>
<DOC>
<DOCNO> 12016 </DOCNO>
A physicist's approach to number partitioning


  The statistical physics approach to the number partioning problem, a
classical NP-hard problem, is both simple and rewarding. Very basic notions and
methods from statistical mechanics are enough to obtain analytical results for
the phase boundary that separates the ``easy-to-solve'' from the
``hard-to-solve'' phase of the NPP as well as for the probability distributions
of the optimal and sub-optimal solutions. In addition, it can be shown that
solving a number partioning problem of size $N$ to some extent corresponds to
locating the minimum in an unsorted list of $\bigo{2^N}$ numbers. Considering
this correspondence it is not surprising that known heuristics for the
partitioning problem are not significantly better than simple random search.

</DOC>
<DOC>
<DOCNO> 101497 </DOCNO>
The spectral gap of the 2-D stochastic Ising model with nearly


  We establish upper bounds for the spectral gap of the stochastic Ising model
at low temperature in an N-by-N box, with boundary conditions which are
``plus'' except for small regions at the corners which are either free or
``minus.'' The spectral gap decreases exponentially in the size of the corner
regions, when these regions are of size at least of order \log N. This means
that removing as few as O(\log N) plus spins from the corners produces a
spectral gap far smaller than the order N^{-2} gap believed to hold under the
all-plus boundary condition. Our results are valid at all subcritical
temperatures.

</DOC>
<DOC>
<DOCNO> 117282 </DOCNO>
The Numerical Solution of Nekrasov's Equation in the Boundary Layer near


  Nekrasov's integral equation describing water waves of permanent form,
determines the angle phi that the wave surface makes with the horizontal. The
independent variable s is a suitably scaled velocity potential, evaluated at
the free surface, with the origin corresponding to the crest of the wave. For
all waves, except for amplitudes near the maximum, phi satisfies the inequality
mod(phi) is less than pi/6. It has been shown numerically and analytically,
that as the wave amplitude approaches its maximum, the maximum of phi can
exceed pi/6 by about 1% near the crest. Numerical evidence suggested that this
occurs in a small boundary layer near the crest where mod(phi(s)) rises rapidly
from zero and oscillates about pi/6, the number of oscillations increasing as
the maximum amplitude is approached. McLeod derived, from Nekrasov's equation,
an integral equation for phi in the boundary layer, whose width tends to zero
as the maximum wave is approached. He also conjectured the asymptotic form of
the oscillations of mod(phi(s)) about pi/6 as s tends to infinity. We solve
McLeod's boundary layer equation numerically and verify the asymptotic form of
phi.

</DOC>
<DOC>
<DOCNO> 169660 </DOCNO>
Removed


  REMOVED by arXiv administration due to meta-abuse

</DOC>
<DOC>
<DOCNO> 120508 </DOCNO>
Amplitude-Phase Analysis of Cosmic Microwave Background maps


  We propose a novel method for the extraction of unresolved point sources from
CMB maps. This method is based on the analysis of the phase distribution of the
Fourier components for the observed signal and unlike most other methods of
denoising does not require any significant assumptions about the expected CMB
signal. The aim of our paper is to show how, using our algorithm, the
contribution from point sources can be separated from the resulting signal on
all scales. We believe that this technique is potentially a very powerful tool
for extracting this type of noise from future high resolution maps.

</DOC>
<DOC>
<DOCNO> 12636 </DOCNO>
Difference between the cleaved surface and the polished surface on the


  The Raman spectra on the cleaved surface of La$_{2-x}$Sr$_x$CuO$_4$ is found
to be different from those on the mechanically polished or chemically etched
surface. On the cleaved surface, the step-like increase of the scattering
intensity below 700 cm$^{-1}$ is washed away and the two-phonon peaks are
preserved clearly even at the optimum doping. The difference is demonstrated on
the optimally doped crystal at x=0.15 and the stripe phase crystal at x=0.115.
The stripe phase is stabilized by defects induced by mechanical polishing.

</DOC>
<DOC>
<DOCNO> 101122 </DOCNO>
Fibre derivatives: some applications to singular lagrangians


  The fibre derivative of a bundle map is studied in detail. In the particular
case of a real function, several constructions useful to study singular
lagrangians are presented. Some applications are given; in particular, a
geometric construction useful to solve the Euler-Lagrange equation of a
singular lagrangian. A free particle in a curved space-time is studied as an
example.

</DOC>
<DOC>
<DOCNO> 99737 </DOCNO>
Counting integral matrices with a given characteristic polynomial


  We give a simpler proof of an earlier result giving an asymptotic estimate
for the number of integral matrices, in large balls, with a given monic
integral irreducible polynomial as their common characteristic polynomial. The
proof uses equidistributions of polynomial trajectories on SL(n,R)/SL(n,Z),
which is a generalization of Ratner's theorem on equidistributions of unipotent
trajectories. We also compute the exact constants appearing in the above
mentioned asymptotic estimate.

</DOC>
<DOC>
<DOCNO> 117046 </DOCNO>
Theory of sub-10 fs Generation in Kerr-lens Mode-locked Solid-State


  The results of the study of ultra-short pulse generation in continuous-wave
Kerr-lens mode-locked (KLM) solid-state lasers with semiconductor saturable
absorbers are presented. The issues of extremely short pulse generation are
addressed in the frames of the theory that accounts for the coherent nature of
the absorber-pulse interaction. We developed an analytical model that bases on
the coupled generalized Landau-Ginzburg laser equation and Bloch equations for
a coherent absorber. We showed, that in the absence of KLM semiconductor
absorber produces 2pi - non-sech-pulses of self-induced transparency, while the
KLM provides an extremely short sech-shaped pulse generation. 2pi- and
pi-sech-shaped solutions and variable-area chirped pulses have been found. It
was shown, that the presence of KLM removes the limitation on the minimal
modulation depth in absorber. An automudulational stability and self-starting
ability were analyzed, too.

</DOC>
<DOC>
<DOCNO> 102707 </DOCNO>
States of quantum systems and their liftings


  Let H(1), H(2) be complex Hilbert spaces, H be their Hilbert tensor product
and let tr2 be the operator of taking the partial trace of trace class
operators in H with respect to the space H(2). The operation tr2 maps states in
H (i.e. positive trace class operators in H with trace equal to one) into
states in H(1). In this paper we give the full description of mappings that are
linear right inverse to tr2. More precisely, we prove that any affine mapping
F(W) of the convex set of states in H(1) into the states in H that is right
inverse to tr2 is given by the tensor product of W with some state D in H(2).
In addition we investigate a representation of the quantum mechanical state
space by probability measures on the set of pure states and a representation --
used in the theory of stochastic Schroedinger equations -- by probability
measures on the Hilbert space. We prove that there are no affine mappings from
the state space of quantum mechanics into these spaces of probability measures.

</DOC>
<DOC>
<DOCNO> 7964 </DOCNO>
Quasiparticle Inelastic Lifetime from Paramagnons in Disordered


  The paramagnon contribution to the quasiparticle inelastic scattering rate in
disordered superconductors is presented. Using Anderson's exact eigenstate
formalism, it is shown that the scattering rate is Stoner enhanced and is
further enhanced by the disorder relative to the clean case in a manner similar
to the disorder enhancement of the long-range Coulomb contribution. The results
are discussed in connection with the possibility of conventional or
unconventional superconductivity in the borocarbides. The results are compared
to recent tunneling experiments on LuNi$_{2}$B$_{2}$C.

</DOC>
<DOC>
<DOCNO> 101361 </DOCNO>
Locally Lagrangian Symplectic and Poisson Manifolds


  We discuss symplectic manifolds where, locally, the structure is that
encountered in Lagrangian dynamics. Exemples and characteristic properties are
given. Then, we refer to the computation of the Maslov classes of a Lagrangian
submanifold. Finally, we indicate the generalization of this type of structures
to Poisson manifolds.

</DOC>
<DOC>
<DOCNO> 120071 </DOCNO>
On the nature of the FBS blue stellar objects and the completeness of


  In Paper I (Mickaelian et al. 1999), we compared the surface density of QSOs
in the Bright Quasar Survey (BQS) and in the First Byurakan Survey (FBS) and
concluded that the completeness of the BQS is of the order of 70% rather than
30-50% as suggested by several authors. A number of new observations recently
became available, allowing a re-evaluation of this completeness. We now obtain
a surface density of QSOs brighter than B = 16.16 in a subarea of the FBS
covering ~2250 deg^2, equal to 0.012 deg^-2 (26 QSOs), implying a completeness
of 53+/-10%.

</DOC>
<DOC>
<DOCNO> 13859 </DOCNO>
Large-N solutions of the Heisenberg and Hubbard-Heisenberg models on the


  We solve the Sp(N) Heisenberg and SU(N) Hubbard-Heisenberg models on the
anisotropic triangular lattice in the large-N limit. These two models may
describe respectively the magnetic and electronic properties of the family of
layered organic materials $\kappa$-(BEDT-TTF)$_2$X. The Heisenberg model is
also relevant to the frustrated antiferromagnet, Cs$_2$CuCl$_4$. We find rich
phase diagrams for each model. The Sp(N) antiferromagnet is shown to have five
different phases as a function of the size of the spin and the degree of
anisotropy of the triangular lattice. The effects of fluctuations at finite-N
are also discussed. For parameters relevant to Cs$_2$CuCl$_4$ the ground state
either exhibits incommensurate spin order, or is in a quantum disordered phase
with deconfined spin-1/2 excitations and topological order. The SU(N)
Hubbard-Heisenberg model exhibits an insulating dimer phase, an insulating box
phase, a semi-metallic staggered flux phase (SFP), and a metallic uniform
phase. The uniform and SFP phases exhibit a pseudogap. A metal-insulator
transition occurs at intermediate values of the interaction strength.

</DOC>
<DOC>
<DOCNO> 13874 </DOCNO>
Low-temperature orientational order and possible domain structures in


  Based on a simple model for ordering of hexagons on square planar lattice, an
attempt has been made to consider possible structure of C(_{60}) fullerite in
its low temperature phase. It is shown that hexagons, imitating fullerens
oriented along (C_{3}) axes of \emph{sc} lattice, can be ordered into an ideal
structure with four non-equivalent molecules in unit cell. Then the energy
degeneracy for each hexagon rotations by (\pi /3) around its (C_{3}) axis
leaves the translational and orientational order in this structure, but leads
to a random distribution of (\pi /3) rotations and hence to {}``averaged{}''
unit cell with two molecules. However the most relevant structural defects are
not these intrinsic \char`\"{}misorientations\char`\"{} but certain walls
between the domains with different sequencies of the above-mentioned two
(non-ideal) sublattices. Numeric estimates have been made for the anisotropic
inter-molecular potential showing that the anisotropy is noticeably smaller for
molecules in walls than in domains.

</DOC>
<DOC>
<DOCNO> 122077 </DOCNO>
Formation of Proto-Globular Cluster Clouds by Thermal Instability


  Many models of globular cluster formation assume the presence of cold dense
clouds in early universe. Here we re-examine the Fall & Rees (1985) model for
formation of proto-globular cluster clouds (PGCCs) via thermal instabilities in
a protogalactic halo. We first argue, based on the previous study by others,
that under the protogalactic environments only nonlinear density
inhomogeneities can condense into PGCCs. We then carry out numerical
simulations of the collapse of overdense clouds in one-dimensional spherical
geometry, including self-gravity and radiative cooling down to T=10^4 K. Since
imprinting of Jeans mass at 10^4 K is essential to this model, here we focus on
the cases where external UV background radiation prevents the formation of H2
molecules and so prevent the cloud from cooling below 10^4 K. The quantitative
results from these simulations can be summarized as follows: 1) Perturbations
smaller than M_min ~ (10^{5.6} M_sun) (n_h/0.05 cm3)^{-2} cool isobarically,
while perturbations larger than M_max ~ (10^8 M_sun) (n_h/0.05 cm3)^{-2} cool
isochorically. On the other hand, intermediate size perturbations (M_min<
M_pgcc < M_max) are compressed supersonically. 2) For supersonically collapsing
clouds, the density compression factor after they cool to T_c=10^4 K range
10^{2.5}-10^6. 3) For supersonically collapsing clouds the Jeans mass can be
reduced to as small as 10^{5.5} M_sun (n_h/0.05 cm3)^{-1/2} at the maximum
compression. 4) The density profile of simulated PGCCs can be approximated by a
constant core with a halo of rho ~ r^{-2} rather than a singular isothermal
sphere.

</DOC>
<DOC>
<DOCNO> 11837 </DOCNO>
Public key cryptography and error correcting codes as Ising models


  We employ the methods of statistical physics to study the performance of
Gallager type error-correcting codes. In this approach, the transmitted
codeword comprises Boolean sums of the original message bits selected by two
randomly-constructed sparse matrices. We show that a broad range of these codes
potentially saturate Shannon's bound but are limited due to the decoding
dynamics used. Other codes show sub-optimal performance but are not restricted
by the decoding dynamics. We show how these codes may also be employed as a
practical public-key cryptosystem and are of competitive performance to modern
cyptographical methods.

</DOC>
<DOC>
<DOCNO> 80634 </DOCNO>
Implementation of C* boundary conditions in the Hybrid Monte Carlo


  In the study of QCD dynamics, C* boundary conditions are physically relevant
in certain cases. In this paper we study the implementation of these boundary
conditions in the lattice formulation of full QCD with staggered fermions. In
particular, we show that the usual even-odd partition trick to avoid the
redoubling of the fermion matrix is still valid in this case. We give an
explicit implementation of these boundary conditions for the Hybrid Monte Carlo
algorithm.

</DOC>
<DOC>
<DOCNO> 12912 </DOCNO>
Transient current spectroscopy of a quantum dot in the Coulomb blockade


  Transient current spectroscopy is proposed and demonstrated in order to
investigate the energy relaxation inside a quantum dot in the Coulomb blockade
regime. We employ a fast pulse signal to excite an AlGaAs/GaAs quantum dot to
an excited state, and analyze the non-equilibrium transient current as a
function of the pulse length. The amplitude and time-constant of the transient
current are sensitive to the ground and excited spin states. We find that the
spin relaxation time is longer than, at least, a few microsecond.

</DOC>
<DOC>
<DOCNO> 12944 </DOCNO>
High-Resolution X-Ray Reflectivity Study of Thin Layered Pt-Electrodes


  The structural interface properties of layered Pt/Ti/SiO2/Si electrodes have
been investigated using high-resolution specular and diffuse x-ray reflectivity
under grazing angles. Currently this multilayer system represents a
technological standard as bottom electrodes for ferroelectric thin film
applications. For the electronic and ferroelectric properties of integrated
devices, the film-electrode interface is of crucial importance. We focused on
Pt-100nm/Ti-10nm/SiO2/Si electrodes prepared under annealing conditions as
employed in industrial processing, prior to the deposition of ferroelectric
films. The comparison between annealed and non-annealed electrodes clearly
revealed strong interfacial effects due to interdiffusion and oxidation of Ti,
especially at the Pt-Ti interface. Migration of Ti into the Pt-layer results in
a clear shift of the critical angle due to enclosure of TiO(2-x) within the
Pt-layer. The heterogeneous distribution of TiO(2-x) suggests a diffusion
mechanism mainly along the Pt-grain boundaries. At the SiO2 interface a
relatively weakly oxidized, remaining Ti-layer of 20 Angstroem could be found,
which is most probably correlated with the remaining adhesion to the substrate.

</DOC>
<DOC>
<DOCNO> 151463 </DOCNO>
Fuzzy Actions and their Continuum Limits


  Previously matrix model actions for ``fuzzy'' fields have been proposed using
non-commutative geometry. They retained ``topological'' properties extremely
well, being capable of describing instantons, $\theta$--states, the chiral
anomaly, and even chiral fermions with no ``doubling''. Here, we demonstrate
that the standard scalar and spinor actions on a $d$--dimensional manifold are
recovered from such actions in the limit of large matrices if their
normalizations are correctly scaled as the limit is taken.

</DOC>
<DOC>
<DOCNO> 12328 </DOCNO>
Influence of disorder and a parallel magnetic field on a Quantum Cascade


  The luminescence spectra of a quantum cascade laser in a strong magnetic
field is influenced significantly by the presence of disorder (charged or
neutral) in the system. An externally applied magnetic field parallel to the
electron plane causes a red shift of the luminescence peak in the absence of
any disorder potential. Our results indicate that the disorder potential tends
to cancel that red shift and causes a rapid decrease of the luminescence peak.
A similar behavior was observed in a recent experiment on QCL in a parallel
magnetic field.

</DOC>
<DOC>
<DOCNO> 69566 </DOCNO>
Two-Neutrino Five-Photon Scattering at Low Energies


  We extend earlier constructions of the effective action for neutrino-photon
scattering, using the connection between low-energy neutrino-photon and
photon-photon scattering together with the known effective Lagrangian
describing low-energy photon scattering in QED. We use this effective action to
calculate analytic expressions for the low-energy cross section for the
(unpolarised) processes $\nu \nubar \to 5 \gamma$, $\nu \gamma \to \nu + 4
\gamma$ and $\gamma \gamma \to \nu \nubar + 3 \gamma$. As a byproduct we derive
compact expressions for the $N$-body phase-space integrals for massless
particles, including those having non-trivial tensor-structure.

</DOC>
<DOC>
<DOCNO> 12397 </DOCNO>
Measurement theory for spinor condensates


  We study the experimental signatures of several states of a Bose-Einstein
condensate of spin-1 atoms by quantum trajectory simulations of Stern-Gerlach
experiments. The measurement process itself creates an apparent random
alignment for the spins, so that it is difficult to distinguish between a
condensate that initially has an alignment in an unknown direction and one with
no alignment at all. Nonetheless, in repeated experiments with identically
prepared condensates, it is possible to discriminate between certain ground
states of the condensate proposed in the literature.

</DOC>
<DOC>
<DOCNO> 170330 </DOCNO>
Preparation and light-mediated distribution of motional state


  We describe and analyse numerically schemes (i) for entangling orthogonal
motional modes of one or a few harmonically-trapped atoms or ions, and (ii) for
transferring the entanglement from one of these local modes to a distant
trapped atom (or atoms) via a light-mediated quantum state transfer procedure
proposed in previous work [A.S. Parkins and H.J. Kimble, J. Opt. B: Quantum
Semiclass. Opt. 1, 496 (1999)]. Possibilities arising from these schemes
include the generation of an Einstein-Podolsky-Rosen state in the positions and
momenta of distantly-separated trapped atoms and the preparation of delocalized
mesoscopic vibrational states.

</DOC>
<DOC>
<DOCNO> 9844 </DOCNO>
Ballistic Annihilation


  Ballistic annihilation with continuous initial velocity distributions is
investigated in the framework of Boltzmann equation. The particle density and
the rms velocity decay as $c=t^{-\alpha}$ and $<v>=t^{-\beta}$, with the
exponents depending on the initial velocity distribution and the spatial
dimension. For instance, in one dimension for the uniform initial velocity
distribution we find $\beta=0.230472...$. We also solve the Boltzmann equation
for Maxwell particles and very hard particles in arbitrary spatial dimension.
These solvable cases provide bounds for the decay exponents of the hard sphere
gas.

</DOC>
<DOC>
<DOCNO> 68520 </DOCNO>
New limits on effective Majorana neutrino masses from rare kaon decays


  The rare kaon decay $K^+ \ra \pi^- \mu^+ \mu^+$ is violating lepton number by
two units and is investigated within the context of Majorana neutrino masses.
Using a new upper bound for this decay from E865 an upper limit on the
effective Majorana mass term $\m_{\mu \mu} < 500$ GeV could be obtained. This
is improving existing bounds by about one order of magnitude. Implications on
heavy neutrinos are discusse d as well as future possibilities to improve
limits on this as well as other elements of the Majorana m ass matrix are
investigated.

</DOC>
<DOC>
<DOCNO> 85254 </DOCNO>
M{\o}ller energy of the nonstatic spherically symmetric metrics


  The energy distribution in the most general nonstatic spherically symmetric
space-time is obtained using M{\o}ller's energy-momentum complex. This result
is compared with the energy expression obtained by using the energy-momentum
complex of Einstein. Some examples of energy distributions in different
prescriptions are discussed.

</DOC>
<DOC>
<DOCNO> 178540 </DOCNO>
Modern nuclear force predictions for the alpha particle


  We present new calculations of the $\alpha$-particle which are based on the
most modern nucleon-nucleon interactions alone and combined with the
Tucson-Melbourne or the Urbana IX three-nucleon interaction. Results for the
binding energies and some properties of the wavefunction are given. On that
phenomenological level little room is left for the action of a possible
four-nucleon force.

</DOC>
<DOC>
<DOCNO> 151237 </DOCNO>
The trace anomaly of the (2,0) tensor multiplet in background gauge


  We study the trace anomaly of the (2,0) tensor multiplet in d=6 in the
presence of a background SO(5) vector field acting as a source for the
R-current. Using both a free-field theory calculation and AdS_7/CFT_6
correspondence, we find that only one of the two possible anomaly structures is
non-zero and that its coefficient at strong-coupling differs by the well-known
overall factor 4N^3 from the corresponding weak coupling result. We also
discuss the relevance of our result to studies of the R-current anomaly in the
(2,0) multiplet.

</DOC>
<DOC>
<DOCNO> 11593 </DOCNO>
Adsorbed 3d transition metal atoms and clusters on Au(111):Signatures


  The spectroscopic characteristics of systems with adsorbed d impurities on
noble metal surfaces should depend on the number and geometric arrangement of
the adsorbed atoms and also on their d band filling. Recent experiments using
scanning tunneling microscopy have probed the electronic structure of all 3d
transition metal impurities and also of Co dimers adsorbed on Au(111),
providing a rich variety of results. In this contribution we correlate those
experimental results with ab-initio calculations and try to establish necessary
conditions for observing a Kondo resonance when using the single impurity
Anderson model. We find that the relevant orbitals at the STM tip position,
when it is on top of an impurity, are the dThe spectroscopic characteristics of
systems with adsorbed d impurities on noble metal surfaces should depend on the
number and geometric arrangement of the adsorbed atoms and also on their d band
filling. Recent experiments using scanning tunneling microscopy have probed the
electronic structure of all 3d transition metal impurities and also of Co
dimers adsorbed on Au(111), providing a rich variety of results. In this
contribution we correlate those experimental results with ab-initio
calculations and try to establish necessary conditions for observing a Kondo
resonance when using the single impurity Anderson model. We find that the
relevant orbitals at the STM tip position, when it is on top of an impurity,
are the d orbitals with m=0 and that the energy of these levels with respect to
the Fermi energy determines the possibility of observing a spectroscopic
feature due to the impurity. orbitals with m=0 and that the energy of these
levels with respect to the Fermi energy determines the possibility of observing
a spectroscopic feature due to the impurity.

</DOC>
<DOC>
<DOCNO> 80712 </DOCNO>
Gauge Field Theory Coherent States (GCS) : I. General Properties


  In this article we outline a rather general construction of diffeomorphism
covariant coherent states for quantum gauge theories.
  By this we mean states $\psi_{(A,E)}$, labelled by a point (A,E) in the
classical phase space, consisting of canonically conjugate pairs of connections
A and electric fields E respectively, such that (a) they are eigenstates of a
corresponding annihilation operator which is a generalization of A-iE smeared
in a suitable way, (b) normal ordered polynomials of generalized annihilation
and creation operators have the correct expectation value, (c) they saturate
the Heisenberg uncertainty bound for the fluctuations of $\hat{A},\hat{E}$ and
(d) they do not use any background structure for their definition, that is,
they are diffeomorphism covariant.
  This is the first paper in a series of articles entitled ``Gauge Field Theory
Coherent States (GCS)'' which aim at connecting non-perturbative quantum
general relativity with the low energy physics of the standard model. In
particular, coherent states enable us for the first time to take into account
quantum metrics which are excited {\it everywhere} in an asymptotically flat
spacetime manifold. The formalism introduced in this paper is immediately
applicable also to lattice gauge theory in the presence of a (Minkowski)
background structure on a possibly {\it infinite lattice}.

</DOC>
<DOC>
<DOCNO> 39835 </DOCNO>
Multiplicity dependence of correlation functions in \bar{p}p reactions


  Discussions about Bose-Einstein correlations between decay products of
coproduced W-bosons again raise the question about the behaviour of
correlations if several strings are produced. This is studied by the
multiplicity dependence of correlation functions of particle pairs with
like-sign and opposite-sign charge in \bar{p}p reactions at sqrt{s} = 630 GeV.

</DOC>
<DOC>
<DOCNO> 11515 </DOCNO>
Gorkov equations for a pseudo-gapped high temperature superconductor


  A theory of superconductivity based on the two-body Cooperon propagator is
presented. This theory takes the form of a modified Gorkov equation for the
Green's function and allows one to model the effect of local superconducting
correlations and long range phase fluctuations on the spectral properties of
high temperature superconductors, both above and below Tc. A model is proposed
for the Cooperon propagator, which provides a simple physical picture of the
pseudo-gap phenomenon, as well as new insights into the doping dependence of
the spectral properties. Numerical calculations of the density of states and
spectral functions based on this model are also presented, and compared with
the experimental STM and ARPES data. It is found, in particular, that the
sharpness of the peaks in the density of states is related to the strength and
the range of the superconducting correlations and that the apparent pseudo-gap
in STM and ARPES can be different, although the underlying model is the same.

</DOC>
<DOC>
<DOCNO> 120404 </DOCNO>
Internal Motions in Globular Clusters


  Observations of internal motions in globular clusters offer unique insights
into the dynamics of the clusters. We have recently developed methods of
high-precision astrometry with HST's WFPC2 camera, which allow us to measure
internal proper motions of individual stars. These new data open up many new
avenues for study of the clusters. Comparison of the dispersion of proper
motion with that of radial velocity offers what is potentially the best method
of measuring cluster distances, but reliable results will require dynamical
modeling of each cluster. Proper motions are much better able to measure
anisotropy of stellar motions than are radial velocities. In 47 Tucanae we have
measured thousands of proper motions near the center; their velocity
distribution is remarkably Gaussian. In two outer fields we have begun to study
anisotropy, which appears in the high velocities but not in the lower ones,
contrary to the spheroidal velocity distributions that have commonly been
assumed.

</DOC>
<DOC>
<DOCNO> 80753 </DOCNO>
Approximate Ginsparg-Wilson Fermions for QCD


  Lattice fermions obeying the Ginsparg-Wilson relation do correctly represent
the physical properties related to chirality. This can be achieved by local
fermions, which involve an infinite number of couplings, however. For practical
purposes, it is useful to first construct approximate Ginsparg-Wilson fermions
within a short range. We report on a successful construction in QCD at \beta
=6. The good quality of the approximation is observed from the spectrum, which
is situated close to a Ginsparg-Wilson circle. These fermions also provide an
excellent approximation to rotational symmetry and they are promising for a
good scaling, since they arise from the perfect action framework. Their
insertion into the overlap formula renders the Ginsparg-Wilson relation exact.
It leads to an improved overlap fermion with a high level of locality. This
insertion is statistically on safe grounds at about \beta > 5.6.

</DOC>
<DOC>
<DOCNO> 120687 </DOCNO>
Calculations at Series Limits in One-Electron Systems


  As soon as Lyman or Balmer lines overlap, the net absorption cross section
rapidly approaches the value at the series limit. Independent of the difficult
question of the relative contributions of line and continuous opacity, we can
get a good estimate of their sum.

</DOC>
<DOC>
<DOCNO> 9715 </DOCNO>
Where is the Luttinger liquid in one dimensional semiconductor quantum


  We present the theoretical basis for analyzing resonant Raman scattering
experiments in one-dimensional systems described by the Luttinger liquid fixed
point. We make experimentally testable predictions for distinguishing Luttinger
liquids from Fermi liquid and argue that presently available quantum wire
systems are \textit{not} in the regime where Luttinger liquid effects are
important.

</DOC>
<DOC>
<DOCNO> 118828 </DOCNO>
An internet server for update pre-main sequence tracks of low- and


  We present new grids of pre-main sequence (PMS) tracks for stars in the mass
range 0.1 to 7.0 Msun. The computations were performed for four different
metallicities (Z=0.01, 0.02, 0.03 and 0.04). A fifth table has been computed
for the solar composition (Z=0.02), including a moderate overshooting. We
describe the update in the physics of the Grenoble stellar evolution code which
concerns mostly changes in the equation of state (EOS) adopting the formalism
proposed by Pols et al. (1995) and in the treatment of the boundary condition.
Comparisons of our models with other grids demonstrate the validity of this EOS
in the domain of very low-mass stars. Finally, we present a new server
dedicated to PMS stellar evolution which allows the determination of stellar
parameters from observational data, the calculation of isochrones, the
retrieval of evolutionary files and the possibility to generate graphic
outputs.
  WWW site : http://www-laog.obs.ujf-grenoble.fr/activites/starevol/evol.html

</DOC>
<DOC>
<DOCNO> 10946 </DOCNO>
Composite defect extends cosmology - 3He analogy


  Spin-mass vortices have been observed to form in rotating superfluid 3He-B
following the absorption of a thermal neutron and a rapid transition from the
normal to superfluid state. The spin-mass vortex is a composite defect which
consists of a planar soliton (wall) which terminates on a linear core (string).
This observation fits well within the framework of a cosmological scenario for
defect formation, known as the Kibble-Zurek mechanism. It suggests that in the
early Universe analogous cosmological defects might have formed.

</DOC>
<DOC>
<DOCNO> 71226 </DOCNO>
Absence of Nonlocal Counter-terms in the Gauge Boson Propagator in Axial


  We study the two-point function for the gauge boson in the axial-type gauges.
We use the exact treatment of the axial gauges recently proposed that is
intrinsically compatible with the Lorentz type gauges in the path-integral
formulation and has been arrived at from this connection and which is a
``one-vector'' treatment. We find that in this treatment, we can evaluate the
two-point functions without imposing any additional interpretation on the axial
gauge 1/(n.q)^p-type poles. The calculations are as easy as the other
treatments based on other known prescriptions. Unlike the
``uniform-prescription'' /L-M prescription, we note, here, the absence of any
non-local divergences in the 2-point proper vertex. We correlate our
calculation with that for the Cauchy Principal Value prescription and find from
this comparison that the 2-point proper vertex differs from the CPV calculation
only by finite terms. For simplicity of treatment, the divergences have been
calculated here with n^2>0 and these have a smooth light cone limit.

</DOC>
<DOC>
<DOCNO> 118133 </DOCNO>
Gyro-Magnetic Relations and Masses of Stars


  The calculations in Thomas-Fermi approximation show that in a gravitational
field each cell of ultra dense matter inside celestial bodies obtains a very
small positive electric charge. A celestial body is electrically neutral as a
whole, because the negative electric charge exists on its surface. On the order
of magnitude the positive volume charge is very small ($10^{-18}e$ only). But
it is sufficient to explain the occurrence of magnetic fields of celestial
bodies and the existence of a discrete spectrum of steady-state values of
masses of stars and pulsars.

</DOC>
<DOC>
<DOCNO> 11212 </DOCNO>
Exact Criterion for Determining Clustering vs. Reentrant Melting


  We examine in full generality the phase behavior of systems whose constituent
particles interact by means of potentials which do not diverge at the origin,
are free of attractive parts and decay fast enough to zero as the interparticle
separation r goes to infinity. By employing a mean field-density functional
theory which is shown to become exact at high temperatures and/or densities, we
establish a criterion which determines whether a given system will freeze at
all temperatures or it will display reentrant melting and an upper freezing
temperature.

</DOC>
<DOC>
<DOCNO> 101920 </DOCNO>
Partial synchronicity and the (max,+) semiring


  In this paper we illustrate how non-stochastic (max,+) techniques can be used
to describe partial synchronization in a Discrete Event Dynamical System. Our
work uses results from the spectral theory of dioids and analyses (max,+)
equations describing various synchronization rules in a simple network. The
network in question is a transport network consisting of two routes joined at a
single point, and our Discrete Events are the departure times of transport
units along these routes. We calculate the maximum frequency of circulation of
these units as a function of the synchronization parameter. These functions
allow us further to determine the waiting times on various routes, and here we
find critical parameters (dependent on the fixed travel times on each route)
which dictate the overall behavoiur. We give explicit equations for these
parameters and state the rules which enable optimal performance in the network
(corresponding to minimum waiting time).

</DOC>
<DOC>
<DOCNO> 169911 </DOCNO>
Parameters estimation in quantum optics


  We address several estimation problems in quantum optics by means of the
maximum-likelihood principle. We consider Gaussian state estimation and the
determination of the coupling parameters of quadratic Hamiltonians. Moreover,
we analyze different schemes of phase-shift estimation. Finally, the absolute
estimation of the quantum efficiency of both linear and avalanche
photodetectors is studied. In all the considered applications, the Gaussian
bound on statistical errors is attained with a few thousand data.

</DOC>
<DOC>
<DOCNO> 116389 </DOCNO>
The Physical-Chemical Mechanism of Water Stream Self-Purification


  The self-purification process of water streams is studied and the
physical-chemical mechanism of it is determined. The naturally occurring
self-purification process at the Boyne River site is monitored. Experiments at
several creeks and rivers in GTA area that induced the self-purification
process are provided. As a result, the concentration of polluting agents in the
water decreases up to 100 % depending on the site and pollutants.

</DOC>
<DOC>
<DOCNO> 99694 </DOCNO>
The distribution of spacings between the fractional parts of $n^2


  We study the distribution of normalized spacings between the fractional parts
of an^2, n=1,2,.... We conjecture that if a is "badly approximable" by
rationals, then the sequence of fractional parts has Poisson spacings, and give
a number of results towards this conjecture. We also present an example of a
Diophantine number a for which the higher correlation functions of the sequence
blow up.

</DOC>
<DOC>
<DOCNO> 116379 </DOCNO>
Comments on the Paper "On the Unification of the Fundamental Forces"


  In this brief paper we justify observations made in El Naschie's paper "On
the Unification of the Fundamental Forces...", on the Planck scale, fractal
space time and the unification of interactions, from different standpoints.

</DOC>
<DOC>
<DOCNO> 84593 </DOCNO>
Black Hole Evaporation and Large Extra Dimensions


  We study the evaporation of black holes in space-times with extra dimensions
of size L. We first obtain a potential which describes the expected behaviors
of very large and very small black holes and then show that a (first order)
phase transition, possibly signaled by an outburst of energy, occurs in the
system when the horizon shrinks below L from a larger value. This is related to
both a change in the topology of the horizon and the restoring of the
translational symmetry along the extra dimensions.

</DOC>
<DOC>
<DOCNO> 121499 </DOCNO>
SN 1997bs in M66: Another Extragalactic Eta Carinae Analog?


  We report on SN 1997bs in NGC 3627 (M66), the first supernova discovered by
the Lick Observatory Supernova Search using the 0.75-m Katzman Automatic
Imaging Telescope (KAIT). Based on its early-time optical spectrum, SN 1997bs
was classified as Type IIn. However, from the BVRI light curves obtained by
KAIT early in the supernova's evolution, and F555W and F814W light curves
obtained from Hubble Space Telescope archival WFPC2 images at late times, we
question the identification of SN 1997bs as a bona fide supernova. We believe
that it is more likely a super-outburst of a very massive luminous blue
variable star, analogous to Eta Carinae, and similar to SN 1961V in NGC 1058
(Filippenko et al. 1995 [AJ, 110, 2261]) and SN 1954J (``Variable 12'') in NGC
2403 (Humphreys & Davidson 1994 [PASP, 106, 1025]). The progenitor may have
survived the outburst, since the SN is seen in early 1998 at m_F555W=23.4,
about 0.5 mag fainter than the progenitor identified by Van Dyk et al. (1999,
[AJ, 118, 2331]) in a pre-discovery image. Based on analysis of its environment
in the Hubble Space Telescope images, the progenitor was not in an H II region
or association of massive stars. The recent discovery of additional objects
with properties similar to those of SN 1997bs suggests that the heterogeneous
class of Type IIn supernovae consists in part of ``impostors.''

</DOC>
<DOC>
<DOCNO> 12992 </DOCNO>
Zigzag equilibrium structure in monatomic wires


  We have applied first-principles density-functional calculations to the study
of the energetics, and the elastic and electronic properties of monatomic wires
of Au, Cu, K, and Ca in linear and a planar-zigzag geometries.
   For Cu and Au wires, the zigzag distortion is favorable even when the linear
wire is stretched, but this is not observed for K and Ca wires.
   In all the cases, the equilibrium structure is an equilateral zigzag (bond
angle of 60$^{\rm o}$).
   Only in the case of Au, the zigzag geometry can also be stabilized for an
intermediate bond angle of 131$^{\rm o}$.
   The relationship between the bond and wire lengths is qualitatively
different for the metallic (Au, Cu and, K) and semiconducting (Ca) wires.

</DOC>
<DOC>
<DOCNO> 118599 </DOCNO>
Cosmic Velocities 2000: A Review


  I review the status of cosmic velocity analysis as of January 2000, with an
emphasis on two key questions: (1) What is the scale of the largest bulk flows
in the universe? and (2) What is the value of beta=Omega_m^{0.6}/b indicated by
cosmic velocities, and what does this tell us about Omega_m itself? These are
the most important issues for cosmic flow analysis, and each has been
controversial in recent years. I argue that a preponderance of the evidence at
present argues against very large scale (> 100 Mpc) bulk flows, and favors beta
= 0.4-0.5, corresponding to a low-density (Omega_m=0.2-0.3) universe.

</DOC>
<DOC>
<DOCNO> 71143 </DOCNO>
New Value of M_mu/M_e from Muonium Hyperfine Splitting


  The complete contribution to the muonium hyperfine splitting of relative
order alpha^3(m_e/m_mu)ln(alpha) is calculated. The result amounts to 0.013
kHZ, much smaller than suggested by a previous estimate, and leads to a 2-sigma
shift of the most precise value for the muon-electron mass ratio, with the
error reduced by approximately 30%. Analogous contributions are calculated for
the positronium hyperfine splitting:
(217/90-17*ln{2}/3)m_e(alpha^7/pi)ln(1/alpha) \approx -0.32 MHz; the remaining
theoretical uncertainty should be well below experimental error, leaving
discrepancies of 2.5-sigma and 3.5-sigma with the two most precise
measurements.

</DOC>
<DOC>
<DOCNO> 170204 </DOCNO>
Squeezing of electromagnetic field in a cavity by electrons in Trojan


  The notion of the Trojan state of a Rydberg electron, introduced by
I.Bialynicki-Birula, M.Kali\'nski, and J.H.Eberly (Phys. Rev. Lett. 73, 1777
(1994)) is extended to the case of the electromagnetic field quantized in
acavity. The shape of the electronic wave packet describing the Trojan state is
practically the same as in the previously studied externally driven system. The
fluctuations of the quantized electromagnetic field around its classical value
exhibit strong squeezing. The emergence of Trojan states in the cylindrically
symmetrical system is attributed to spontaneous symmetry braking.

</DOC>
<DOC>
<DOCNO> 151084 </DOCNO>
Strings and branes with a modified measure


  In string theory, the consequences of replacing the measure of integration
$\sqrt{-\gamma}d^2 x$ in the Polyakov's action by $\Phi d^2 x$ where $\Phi$ is
a density built out of degrees of freedom independent of the metric
$\gamma_{ab}$ defined in the string are studied. The string tension appears as
an integration constant of the equations of motion. The string tension can
change in different parts of the string due to the coupling of gauge fields and
point particles living in the string. The generalization to higher dimensional
extended objects is also studied. In this case there is no need of a fine tuned
cosmological term, in sharp contrast to the standard formulation of the
generalized Polyakov action for higher dimensional branes.

</DOC>
<DOC>
<DOCNO> 116809 </DOCNO>
Quadrupole Misalignments and Steering in Long Linacs


  We present a study of orbit jitter and emittance growth in a long linac
caused by misalignment of quadrupoles. First, assuming a FODO lattice, we
derive analytical formulae for the RMS deviation of the orbit and the emittance
growth caused by random uncorrelated misalignments of all quadrupoles. We then
consider an alignment algorithm based on minimization of BPM readings with a
given BPM resolution and finite mover steps.

</DOC>
<DOC>
<DOCNO> 174508 </DOCNO>
Structure of isobaric analog states in 91Nb populated by the 90Zr(a,t)


  Decay via proton emission of isobaric analog states (IAS's) in $^{91}{Nb}$
was studied using the $^{90}{Zr}(\alpha,t)$ reaction at $E_\alpha$=180 MeV.
This study provides information about the damping mechanism of these states.
Decay to the ground state and low-lying phonon states in $^{90}{Zr}$ was
observed. The experimental data are compared with theoretical predictions
wherein the IAS `single-particle' proton escape widths are calculated in a
continuum RPA approach. The branching ratios for decay to the phonon states are
explained using a simple model.

</DOC>
<DOC>
<DOCNO> 68735 </DOCNO>
Gluon and quark distributions in large N_c QCD: theory vs. phenomenology


  We present the QCD analysis of the behavior of quark and gluon distributions
in the limit of a large number of colors N_c. We show that the results agree
qualitatively with the phenomenological data. In particular we draw attention
to the fact that the polarized gluon distribution is suppressed at large N_c
compared to the unpolarized one.

</DOC>
<DOC>
<DOCNO> 121275 </DOCNO>
Probing the warm Inter-Galactic Medium through absorption against Gamma


  Gamma Ray Burst (GRB) afterglows close to their peak intensity are among the
brightest X-ray sources in the sky. Despite their fast power-law like decay,
when fluxes are integrated from minutes up to hours after the GRB event, the
corresponding number counts (logN-logF relation) far exceeds that of any other
high redshift (z>0.5) source, the flux of which is integrated over the same
time interval. We discuss how to use X-ray afterglows of GRBs as distant
beacons to probe the warm (10^5 K<T<10^7 K) intergalactic matter in filaments
and outskirts of clusters of galaxies by means of absorption features, the
``X-ray forest''. According to current cosmological scenarios this matter may
comprise 30-40% of the baryons in the Universe at z<1. Present-generation X-ray
spectrometers such as those on Chandra and XMM-Newton can detect it along most
GRBs' lines of sight, provided afterglows are observed fast enough (within
hours) after the burst. A dedicated medium-sized X-ray telescope (effective
area <=0.1 m^2) with pointing capabilities similar to that of Swift (minutes)
and high spectral resolution (E/DeltaE>=300) would be very well suited to
exploit the new diagnostic and study the physical conditions in the Universe at
the critical moment when structure is being formed.

</DOC>
<DOC>
<DOCNO> 150938 </DOCNO>
Ultraviolet Property of Noncommutative Wess-Zumino-Witten Model


  We construct noncommutative extension of the Wess-Zumino-Witten (WZW) model
and study its ultraviolet property. The \beta-function of the U(N)
noncommutative WZW model resembles that of the ordinary WZW model. The U(1)
noncommutative model has also a nontrivial fixed point.

</DOC>
<DOC>
<DOCNO> 102496 </DOCNO>
Torsion in K-theory for boundary actions on affine buildings of type


  Let $\Gamma$ be a torsion free lattice in $G = \PGL(n+1,\FF)$, where $n\ge 1$
and $\FF$ is a non-archimedean local field. Then $\Gamma$ acts on the
Furstenberg boundary $G/P$, where $P$ is a minimal parabolic subgroup of $G$.
The identity element $\id$ in the crossed product $C^*$-algebra $C(G/P)\rtimes
\Gamma$ generates a class $[\id]$ in the $K_0$ group of $C(G/P)\rtimes \Gamma$.
It is shown that $[\id]$ is a torsion element of $K_0$ and there is an explicit
bound for the order of $[\id]$. The result is proved more generally for groups
acting on affine buildings of type $\tA_n$. For $n=1, 2$ the Euler-Poincar\'e
characteristic $\chi(\Gamma)$ annihilates the class $[\id]$.

</DOC>
<DOC>
<DOCNO> 69725 </DOCNO>
Reduction and evaluation of two-loop graphs with arbitrary masses


  We describe a general analytic-numerical reduction scheme for evaluating any
2-loop diagrams with general kinematics and general renormalizable
interactions, whereby ten special functions form a complete set after tensor
reduction. We discuss the symmetrical analytic structure of these special
functions in their integral representation, which allows for optimized
numerical integration. The process Z -> bb is used for illustration, for which
we evaluate all the 3-point, non-factorizable g^2*alpha_s mixed electroweak-QCD
graphs, which depend on the top quark mass. The isolation of infrared
singularities is detailed, and numerical results are given for all two-loop
three-point graphs involved in this process.

</DOC>
<DOC>
<DOCNO> 102779 </DOCNO>
Invitation to higher local fields, Part I, section 14: Explicit abelian


  This work presents author's explicit methods of constructing abelian
extensions of complete discrete valuation fields. His approach to explicit
equations of a cyclic extension of degree p^n which contains a given cyclic
extension of degree p is explained.

</DOC>
<DOC>
<DOCNO> 13599 </DOCNO>
Simulation of the Impact of Two-Dimensional Elastic Disks


  The impact of a two-dimensional elastic disk with a wall is numerically
studied. It is clarified that the coefficient of restitution (COR) decreases
with the impact velocity. The result is not consistent with the recent
quasi-static theory of inelastic collisions even for very slow impact. The
abrupt drop of COR has been found due to the plastic deformation of the disk,
which is assisted by the initial internal motion. (to be published in
Proceedings of 9 th Nisshin Engineering Particle Technology International
Symposium on 'Solids Flow Mechanics and Their Applications' held at Kyoto,
7th-9th January, 2001

</DOC>
<DOC>
<DOCNO> 70589 </DOCNO>
Dark Matter and Detector Cross Sections


  We consider here the spin independent neutralino-proton cross section for a
variety of SUGRA and D-brane models with R-parity invariance. The minimum cross
section generally is >~ 1\times 10^{-(9-10)} pb (and hence accessible to future
detectors) except for special regions of parameter space where it may drop to
=~ 10^{-12} pb. In the latter case the gluino and squarks will be heavy (>~ 1
TeV).

</DOC>
<DOC>
<DOCNO> 117280 </DOCNO>
Squeezing mode in nuclear collisions


  The time dependent Schroedinger equation is solved analytically for a
simplified model of moving infinite walls. A new knock-out mode is described
which might occur during heavy ion collisions. The outer shell-nucleons are
ionised due to the increase of level energy when two nuclei are approaching
fast enough. This is analogous to the Mott effect but in contrast occurs only
if the reaction time is short enough that no common ionisation threshold in the
compound system is established. To demonstrate this pure nonequilibrium effect
a simulation of realistic heavy ion collision by a nonlocal Boltzmann equation
is performed.

</DOC>
<DOC>
<DOCNO> 119250 </DOCNO>
On the Perils of Hyperfine Splitting: A reanalysis of Mn and Sc


  We investigate the impact of hyperfine splitting on stellar abundance
analyses of Mn and Sc, and find that incorrect hfs treatment can lead to
spurious abundance trends with metallicity. We estimate corrections to a recent
study by Nissen et al. (2000), and find: (1) [Mn/Fe] is described by a bimodal
distribution, with [Mn/Fe] ~ -0.3 for stars [Fe/H] < -0.7, and [Mn/Fe] ~ -0.05
for stars at higher metallicity, suggestive of a transition between halo/thick
disk and thin disk populations. (2) The large majority of stars show nearly
solar [Sc/Fe] ratios; although important deviations cannot be ruled-out.

</DOC>
<DOC>
<DOCNO> 170749 </DOCNO>
Spectral Oscillations, Periodic Orbits, and Scaling


  The eigenvalue density of a quantum-mechanical system exhibits oscillations,
determined by the closed orbits of the corresponding classical system; this
relationship is simple and strong for waves in billiards or on manifolds, but
becomes slightly muddy for a Schrodinger equation with a potential, where the
orbits depend on the energy. We discuss several variants of a way to restore
the simplicity by rescaling the coupling constant or the size of the orbit or
both. In each case the relation between the oscillation frequency and the
period of the orbit is inspected critically; in many cases it is observed that
a characteristic length of the orbit is a better indicator. When these matters
are properly understood, the periodic-orbit theory for generic quantum systems
recovers the clarity and simplicity that it always had for the wave equation in
a cavity. Finally, we comment on the alleged "paradox" that semiclassical
periodic-orbit theory is more effective in calculating low energy levels than
high ones.

</DOC>
<DOC>
<DOCNO> 101610 </DOCNO>
Regularity of induced representations and a theorem of Quigg and


  The Symmetric Imprimitivity Theorem provides a Morita equivalence between two
crossed products of induced C*-algebras. Quigg and Spielberg proved, by
indirect but ingenious methods, that the symmetric imprimitivity theorem has an
analog for reduced crossed products. Here we identify the representations which
induce to regular representations under the equivalence of the symmetric
theorem. We use this result to show that regular representations themselves
almost always induce to regular representations. In addition, we obtain a
direct proof of the theorem of Quigg and Spielberg.

</DOC>
<DOC>
<DOCNO> 14075 </DOCNO>
Cold Trapped Atoms: A Mesoscopic System


  The Bose-Einstein condensates recently created in trapped atomic gases are
mesoscopic systems, in two senses: (a) Their size fall between macroscopic and
microscopic systems; (b) They have a quantum phase that can be manipulated in
experiments. We review the theoretical and experimental facts about trapped
atomic gases, and give examples that emphasize their mesoscopic characters. One
is the dynamics of collapse of a condensate with attractive interactions. The
other is the creation of a 1D kink soliton that can be used as a mode-locked
atom laser.

</DOC>
<DOC>
<DOCNO> 169764 </DOCNO>
Measurements of Nondegenerate Discrete Observables


  Every measurement on a quantum system causes a state change from the system
state just before the measurement to the system state just after the
measurement conditional upon the outcome of measurement. This paper determines
all the possible conditional state changes caused by measurements of
nondegenerate discrete observables. For this purpose, the following conditions
are shown to be equivalent for measurements of nondegenerate discrete
observables: (i) The joint probability distribution of the outcomes of
successive measurements depends affinely on the initial state. (ii) The
apparatus has an indirect measurement model. (iii) The state change is
described by a positive superoperator valued measure. (iv) The state change is
described by a completely positive superoperator valued measure. (v) The output
state is independent of the input state and the family of output states can be
arbitrarily chosen by the choice of the apparatus. The implications to the
measurement problem are discussed briefly.

</DOC>
<DOC>
<DOCNO> 70028 </DOCNO>
Estimating the effect of NNLO contributions on global parton analyses


  We use the recent estimates of NNLO splitting functions, made by van Neerven
and Vogt, to perform exploratory fits to deep inelastic and related hard
scattering data. We investigate the hierarchy of parton distributions obtained
at LO, NLO and NNLO, and, more important, the stability of the resulting
predictions for physical observables. We use the longitudinal structure
function $F_L$ and the cross sections $\sigma_W, \sigma_Z$ for $W$ and $Z$
hadroproduction as examples. For $F_L$ we find relatively poor convergence,
with increasing order, at small $x$; whereas $\sigma_{W,Z}$ are much more
reliably predicted.

</DOC>
<DOC>
<DOCNO> 122402 </DOCNO>
Searching for X-ray Galaxy Clusters in the Zone of Avoidance


  Based on the ROSAT All-Sky Survey we are constructing a sample of the X-ray
brightest galaxy clusters for cosmological studies. We have already completed
the compilation of a sample of about 1000 clusters in the sky excluding a 40
degree wide band around the galactic plane. We have demonstrated with the
southern sample, which is the so far most complete, that we can get reliable
statistical measures of the large-scale structure of the Universe to scales in
excess of 400 Mpc (for Ho=100). With the experience gained in these projects we
are extending the search for X-ray galaxy clusters into the Zone-of-Avoidance.
We have compiled a sample of 181 good cluster candidates with a well defined
completeness of about 70% down to a flux limit of 3 10e-12 erg/s/cm**2 in the
zone with an absorption depth less than Av = 2.25. The candidates are
definitely identified and redshifts are obtained in an ongoing optical
follow-up program.

</DOC>
<DOC>
<DOCNO> 178661 </DOCNO>
Chiral Unitary Approach to the Kaon Nucleus Interaction and Kaonic Atoms


  We review recent work on various topics related to the modification of kaon
properties in nuclei. After a brief exposition of the kaon-nucleon and
kaon-nucleus interaction, results from the application to kaonic atoms,
renormalization of the f0 and a0 scalar resonances in nuclei and phi decay in
the nucleus are shown.

</DOC>
<DOC>
<DOCNO> 68583 </DOCNO>
Study of R-parity-violating supersymmetric signals at an e-e- collider


  We study the pair production of right selectrons at a 500 GeV $e^-e^-$
collider followed by their decay into an electron and a lightest neutralino.
This lightest neutralino decays into multifermion final states in the presence
of R-parity-violating couplings. A detailed analysis of possible signals is
performed for some important regions of the parameter space. The signals are
essentially free from the standard model backgrounds.

</DOC>
<DOC>
<DOCNO> 39926 </DOCNO>
Examining CP Symmetry in Strange Baryon Decays


  Non-conservation of CP symmetry can manisfest itself in non-leptonic hyperon
decays as a difference in the decay parameter between the strange-baryon decay
and its charge conjugate. By comparing the decay distribution in the $\Lambda$
helicity frame for the decay sequence $\Xi^{-} \to \Lambda \pi^{-}$, $\Lambda
\to p \pi^{-}$ with that of $\bar{\Xi}^{+}$ decay, E756 at Fermilab did not
observe any CP-odd effect at the $10^{-2}$ level. The status of a follow-up
experiment, HyperCP (FNAL E871), to search for CP violation in charged
$\Xi-\Lambda$ decay with a sensitivity of $10^{-4}$ is also presented.

</DOC>
<DOC>
<DOCNO> 116579 </DOCNO>
Analytical estimation of the dynamic apertures of circular accelerators


  By considering delta function sextupole, octupole, and decapole perturbations
and using difference action-angle variable equations, we find some useful
analytical formulae for the estimation of the dynamic apertures of circular
accelerators due to single sextupole, single octupole, single decapole (single
2$m$ pole in general). Their combined effects are derived based on the Chirikov
criterion of the onset of stochastic motions. Comparisons with numerical
simulations are made, and the agreement is quite satisfactory. These formulae
have been applied to determine the beam-beam limited dynamic aperture in a
circular collider.

</DOC>
<DOC>
<DOCNO> 102701 </DOCNO>
Link-homotopy Invariants of Finite Type


  An explicit polynomial in the linking numbers $l_{ij}$ and Milnor's triple
linking numbers $\mu(rst)$ on six component links is shown to be a well-defined
finite type link-homotopy invariant. This solves a problem raised by B. Mellor
and D. Thurston. An extension of our construction also produces a finite type
link invariant which detects the invertibility for some links.

</DOC>
<DOC>
<DOCNO> 69275 </DOCNO>
Radiative pion capture by a nucleon


  The differential cross sections for $\pi^- p \to \gamma n$ and $\pi^+ n \to
\gamma p$ are computed up to $O(p^3)$ in heavy baryon chiral perturbation
theory (HBChPT). The expressions at $O(p)$ and $O(p^2)$ have no free
parameters. There are three unknown parameters at $O(p^3)$, low energy
constants of the HBChPT Lagrangian, which are determined by fitting to
experimental data. Two acceptable fits are obtained, which can be separated by
comparing with earlier dispersion relation calculations of the inverse process.
Expressions for the multipoles, with emphasis on the p-wave multipoles, are
obtained and evaluated at threshold. Generally the results obtained from the
best of the two fits are in good agreement with the dispersion relation
predictions.

</DOC>
<DOC>
<DOCNO> 120215 </DOCNO>
Direct imaging search for planetary companions next to young nearby


  We report first results from our ground-based infrared imaging search for
sub-stellar companions (brown dwarfs and giant planets) of young (up to 100
Myrs) nearby (up to 75 pc) stars, where companions should be well separated
from the central stars and still relatively bright due to ongoing accretion
and/or contraction. Among our targets are all members of the TW Hya
association, as well as other binary and single young stars either discovered
recently among ROSAT sources (some of which as yet unpublished) or known
before. Our observations are performed mainly with SOFI and SHARP at the ESO
3.5m NTT on La Silla and with ISAAC at the ESO 8.2m Antu (VLT-UT1) on Cerro
Paranal, all in the H- and K-bands. We present direct imaging data and H-band
spectroscopy of a faint object detected next to TWA-7 which, if at the same age
and distance as the central star, could be an object with only a few Jupiter
masses. Our spectrum shows, though, that it is a background K-dwarf.

</DOC>
<DOC>
<DOCNO> 117454 </DOCNO>
A Search for X-ray emission from Saturn, Uranus and Neptune


  We present an analysis of X-ray observations of the trans-Jovian planets
Saturn, Uranus and Neptune with the ROSAT PSPC in comparison with X-ray
observations of Jupiter. For the first time a marginal X-ray detection of
Saturn was found and 95% confidence upper limits for Uranus and Neptune were
obtained. These upper limits show that Jupiter-like X-ray luminosities can be
excluded for all three planets, while they are consistent assuming intrinsic
Saturn-like X-ray luminosities. Similar X-ray production mechanisms on all
trans-Jovian planets can therefore not be ruled out, and spectral shape and
total luminosity observed from Saturn are consistent with thick-target
bremsstrahlung caused by electron precipitation as occurring in auroral
emission from the Earth.

</DOC>
<DOC>
<DOCNO> 116678 </DOCNO>
Higher Order Force Gradient Symplectic Algorithms


  We show that a recently discovered fourth order symplectic algorithm, which
requires one evaluation of force gradient in addition to three evaluations of
the force, when iterated to higher order, yielded algorithms that are far
superior to similarly iterated higher order algorithms based on the standard
Forest-Ruth algorithm. We gauge the accuracy of each algorithm by comparing the
step-size independent error functions associated with energy conservation and
the rotation of the Laplace-Runge-Lenz vector when solving a highly eccentric
Kepler problem. For orders 6, 8, 10 and 12, the new algorithms are
approximately a factor of $10^3$, $10^4$, $10^4$ and $10^5$ better.

</DOC>
<DOC>
<DOCNO> 14159 </DOCNO>
Quantization of Thermodynamics, Supersecondary Quantization, and a New


  In solving the problem of finding a temperature distribution which, at zero
temperature, corresponds to superfluidity, i.e., to nonzero energy, the author
tried to quantize free energy. This was done on the basis of supersecondary
quantization whose special case is the usual secondary quantization for bosons
and with the help of which new representations of the Schr\"odinger equation
were obtained. The supersecondary quantization allowed the author to construct
a variational method whose zero approximation are the Hartree-Fock and
Bogolyubov-BCSch variational principles. This method works especially well in
the case of not a large number of particles. The new quantization and the
variational method are of general character and can be used in the quantum
field theory.

</DOC>
<DOC>
<DOCNO> 170710 </DOCNO>
Distilling a Greenberger-Horne-Zeilinger State From an Arbitrary Pure


  We present a general algorithm to achieve local operators which can produce
the GHZ state for an arbitrary given three-qubit state. Thus the distillation
process of the state can be realized optimally. The algorithm is shown to be
sufficient for the three-qubit state on account of the fact that any state for
which this distillation algorithm is invalid cannot be distilled to the GHZ
state by any local actions. Moreover, an analytical result of distillation
operations is achieved for the general state of three qubits.

</DOC>
<DOC>
<DOCNO> 117381 </DOCNO>
On the origin of the luminosity - metallicity relation for late-type


  We consider the roles of two widely invoked mechanisms for the
metallicity-luminosity correlation among late-type galaxies: higher astration
level and decreasing efficiency of heavy-element loss with increasing
luminosity. We find that both mechanisms contribute about equally to the range
in oxygen abundance between low (logL_B = 8) and high (logL_B = 10.5)
luminosity galaxies.
   We also consider the transition from spirals to irregulars, finding that
both the oxygen abundance deficiency (indicating the degree of mass exchange
between a galaxy and its environment) and the gas fraction vary smoothly along
the sequence. Thus we find no "irregular versus spiral dichotomy".

</DOC>
<DOC>
<DOCNO> 169896 </DOCNO>
Quantum Computing Using Dissipation to Remain in a Decoherence-Free


  We propose a new approach to the implementation of quantum gates in which
decoherence during the gate operations is strongly reduced. This is achieved by
making use of an environment induced quantum Zeno effect that confines the
dynamics effectively to a decoherence-free subspace.

</DOC>
<DOC>
<DOCNO> 67661 </DOCNO>
SO(10) and Large nu_mu - nu_tau Mixing


  A general approach to understanding the large mixing seen in atmospheric
neutrinos is explained, as well as a highly predictive SO(10) model which
implements this approach. It is also seen how bimaximal mixing naturally arises
in this scheme. (Talk presented at NNN99, SUNY Stony Brook, Sept. 22-26, 1999)

</DOC>
<DOC>
<DOCNO> 151032 </DOCNO>
Hodge decomposition theorem for Abelian two form gauge theory


  We show that the BRST/anti-BRST invariant 3+1 dimensional 2-form gauge theory
has further nilpotent symmetries (dual BRST /anti-dual BRST) that leave the
gauge fixing term invariant. The generator for the dual BRST symmetry is
analogous to the co-exterior derivative of differential geometry. There exists
a bosonic symmetry which keeps the ghost terms invariant and it turns out to be
the analogue of the Laplacian operator. The Hodge duality operation is shown to
correspond to a discrete symmetry in the theory. The generators of all these
continuous symmetries are shown to obey the algebra of the de Rham cohomology
operators of differential geometry. We derive the extended BRST algebra
constituted by six conserved charges and discuss the Hodge decomposition
theorem in the quantum Hilbert space of states.

</DOC>
<DOC>
<DOCNO> 151908 </DOCNO>
Large-N Theory from the Axiomatic Point of View


  The state space and observables for the leading order of the large-N theory
are constructed. The obtained model ("theory of infinite number of fields") is
shown to obey Wightman-type axioms (including invariance under boost
transformations) and to be nontrivial (there are scattering processes, bound
states, unstable particles etc). The considered class of exactly solvable
relativistic quantum models involves good examples of theories containing such
difficulties as volume divergences associated with the Haag theorem,
Stueckelberg divergences and infinite renormalization of the wave function.

</DOC>
<DOC>
<DOCNO> 10756 </DOCNO>
The fractional quantum Hall effect in infinite layer systems


  Stacked two dimensional electron systems in transverse magnetic fields
exhibit three dimensional fractional quantum Hall phases. We analyze the
simplest such phases and find novel bulk properties, e.g., irrational braiding.
These phases host ``one and a half'' dimensional surface phases in which motion
in one direction is chiral. We offer a general analysis of conduction in the
latter by combining sum rule and renormalization group arguments, and find that
when interlayer tunneling is marginal or irrelevant they are chiral semi-metals
that conduct only at T > 0 or with disorder.

</DOC>
<DOC>
<DOCNO> 8351 </DOCNO>
Self-Duality in Superconductor-Insulator Quantum Phase Transitions


  It is argued that close to a Coulomb interacting quantum critical point, the
interaction between two vortices in a disordered superconducting thin film
separated by a distance $r$ changes from logarithmic in the mean-field region
to $1/r$ in the region dominated by quantum critical fluctuations. This gives
support to the charge-vortex duality picture of the observed reflection
symmetry in the current-voltage characteristics on both sides of the
transition.

</DOC>
<DOC>
<DOCNO> 118548 </DOCNO>
Extreme Energy nu_tau Propagation Through the Earth


  The propagation of extremely energetic nu_tau's through the Earth is studied
by means of a detailed Monte Carlo simulation. All major mechanisms of nu_tau
interactions and tau energy loss as well as all its relevant decay modes are
properly taken into account. The detection possibility of nu_tau's emerging
from Earth in forthcoming neutrino telescopes is addressed

</DOC>
<DOC>
<DOCNO> 69240 </DOCNO>
Quintessential Vanishing of the Cosmological Constant


  We consider an effective field theory description of gravity coupled to a
scalar field with volume-preserving diffeomorphism and Weyl invariances. The
smallness of the cosmological constant is achieved when the potential of the
scalar is extremely flat. This implies a possible relationship between the
smallness and the quintessential sector of the cosmological constant.

</DOC>
<DOC>
<DOCNO> 101474 </DOCNO>
Characterization of ${\bf C}^n$ by its automorphism group


  We show that if the group of holomorphic automorphisms of a connected Stein
manifold $M$ is isomorphic to that of ${\bf C}^n$ as a topological group
equipped with the compact-open topology, then $M$ is biholomorphically
equivalent to ${\bf C}^n$.

</DOC>
<DOC>
<DOCNO> 101164 </DOCNO>
Topological restrictions for circle actions and harmonic morphisms


  Let $M^m$ be a compact oriented smooth manifold which admits a smooth circle
action with isolated fixed points which are isolated as singularities as well.
Then all the Pontryagin numbers of $M^m$ are zero and its Euler number is
nonnegative and even. In particular, $M^m$ has signature zero. Since a
non-constant harmonic morphism with one-dimensional fibres gives rise to a
circle action we have the following applications: (i) many compact manifolds,
for example $CP^{n}$, $K3$ surfaces, $S^{2n}\times P_g$ ($n\geq2$) where $P_g$
is the closed surface of genus $g\geq2$ can never be the domain of a
non-constant harmonic morphism with one-dimensional fibres whatever metrics we
put on them; (ii) let $(M^4,g)$ be a compact orientable four-manifold and
$\phi:(M^4,g)\to(N^3,h)$ a non-constant harmonic morphism. Suppose that one of
the following assertions holds: (1) $(M^4,g)$ is half-conformally flat and its
scalar curvature is zero, (2) $(M^4,g)$ is Einstein and half-conformally flat,
(3) $(M^4,g,J)$ is Hermitian-Einstein. Then, up to homotheties and Riemannian
coverings, $\phi$ is the canonical projection $T^4\to T^3$ between flat tori.

</DOC>
<DOC>
<DOCNO> 99617 </DOCNO>
Growth of sumsets in abelian semigroups


  Let S be an abelian semigroup, written additively. Let A be a finite subset
of S. We denote the cardinality of A by |A|. For any positive integer h, the
sumset hA is the set of all sums of h not necessarily distinct elements of A.
We define 0A = {0}. If A_1,...,A_r, and B are finite sumsets of A and
h_1,...,h_r are nonnegative integers, the sumset h_1A + ... + h_rA_r + B is the
set of all elements of S that can be represented in the form u_1 + ... + u_r +
b, where u_i \in h_iA_i and b \in B. The growth function of this sumset is
\gamma(h_1,...,h_r) = |h_1A + ... + h_rA_r + B|. Applying the Hilbert function
for graded modules over graded algebras, where the grading is over the
semigroup of r-tuples of nonnegative integers, we prove that there is a
polynomial p(t_1,...,t_r) such that \gamma(h_1,...,h_r) = p(t_1,...,t_r) if
min(h_1,...,h_r) is sufficienlty large.

</DOC>
<DOC>
<DOCNO> 170233 </DOCNO>
Triviality of GHZ operators of higher spin


  We prove that local observables of the set of GHZ operators for particles of
spin higher than 1/2 reduce to direct sums of the spin 1/2 operators
$\sigma_x$, $\sigma_y$ and, therefore, no new contradictions with local realism
arise by considering them.

</DOC>
<DOC>
<DOCNO> 71829 </DOCNO>
Classical Initial Conditions for Ultrarelativistic Heavy Ion Collisions


  We construct an analytical expression for the distribution of gluons in the
state immediately following a heavy ion collision in the quasi-classical limit
of QCD given by McLerran-Venugopalan model. The resulting gluon number
distribution function includes the effects of all multiple rescatterings of
gluons with the nucleons of both colliding nuclei. The typical transverse
momentum k of the produced gluons is shown to be of the order of the saturation
scale of the nuclei Qs, as predicted by Mueller. We analyze the properties of
the obtained distribution and demonstrate that due to multiple rescatterings it
remains finite (up to logarithms of k) in the soft transverse momentum limit of
k << Qs unlike the usual perturbative initial conditions given by collinear
factorization. We calculate the total number of produced gluons and show that
it is proportional to the total number of gluons inside the nuclear wave
function before the collision with the proportionality coefficient c = 2 ln2.

</DOC>
<DOC>
<DOCNO> 99682 </DOCNO>
Wavelets with the Translation Invariance Property of Order N


  All wavelets can be associated to a multiresolution like structure, i.e. an
incr easing sequence of subspaces of L^2(R). We consider the interaction of a
wavel et and the translation operator in terms of which of the subspaces in
this multi resolution like structure are invariant under the translation
operator. This ac tion defines the notion of the translation invariance
property of order n. In this paper we show that wavelets of all levels of
translation invariance exist, first for the classic case of dilation by 2, and
then for arbitrary integral di lation factors.

</DOC>
<DOC>
<DOCNO> 40294 </DOCNO>
Photon Structure


  The structure of the photon is probed in photon-photon interactions at LEP
and in photon-proton interactions at HERA.

</DOC>
<DOC>
<DOCNO> 101065 </DOCNO>
Limitations on the smooth confinement of an unstretchable manifold


  We prove that an m-dimensional unit ball D^m in the Euclidean space {\mathbb
R}^m cannot be isometrically embedded into a higher-dimensional Euclidean ball
B_r^d \subset {\mathbb R}^d of radius r < 1/2 unless one of two conditions is
met -- (1)The embedding manifold has dimension d >= 2m. (2) The embedding is
not smooth. The proof uses differential geometry to show that if d<2m and the
embedding is smooth and isometric, we can construct a line from the center of
D^m to the boundary that is geodesic in both D^m and in the embedding manifold
{\mathbb R}^d. Since such a line has length 1, the diameter of the embedding
ball must exceed 1.

</DOC>
<DOC>
<DOCNO> 67702 </DOCNO>
On Importance of Inelastic Rescatterings in Pion Double Charge Exchange


  Different aspects of the Gribov--Glauber approach for calculation of
inclusive pion double charge exchange (DCX) on nuclei are investigated.
Recently we have shown that inelastic rescatterings (IR) with two (and more)
pions in the intermediate states give an important contribution to the process
of DCX at energies above $\sim0.6 GeV$. In this paper we use the one pion
exchange model to study in details amplitudes of two pion production. This
allows us to verify theoretical assumptions made in the previous paper and to
predict cross section for the forward inclusive pion DCX at energies $\ga1
GeV$, where IR dominate over the conventional DCX mechanism of two sequential
single charge exchanges.

</DOC>
<DOC>
<DOCNO> 99597 </DOCNO>
Quantum ergodicity of C* dynamical systems


  This paper contains a very simple and general proof that eigenfunctions of
quantizations of classically ergodic systems become uniformly distributed in
phase space. This ergodicity property of eigenfunctions f is shown to follow
from a convexity inequality for the invariant states (Af,f). This proof of
ergodicity of eigenfunctions simplifies previous proofs (due to A.I.
Shnirelman, Colin de Verdiere and the author) and extends the result to the
much more general framework of C* dynamical systems.

</DOC>
<DOC>
<DOCNO> 179012 </DOCNO>
Unblocking of the Gamow-Teller strength in stellar electron capture on


  We propose a new model to calculate stellar electron capture rates for
neutron-rich nuclei. These nuclei are encountered in the core-collapse of a
massive star. Using the Shell Model Monte Carlo approach, we first calculate
the finite temperature occupation numbers in the parent nucleus. We then use
these occupation numbers as a starting point for calculations using the random
phase approximation. Using the RPA approach, we calculate electron capture
rates including both allowed and forbidden transitions. Such a hybrid model is
particularly useful for nuclei with proton numbers Z<40 and neutron numbers
N>40, where allowed Gamow-Teller transitions are only possible due to
configuration mixing by the residual interaction and by thermal unblocking of
$pf$-shell single-particle states. Using the even germanium isotopes Ge-68 to
Ge-76 as examples, we demonstrate that the configuration mixing is strong
enough to unblock the Gamow-Teller transitions at all temperatures relevant to
core-collapse supernovae.

</DOC>
<DOC>
<DOCNO> 120669 </DOCNO>
Observing the Unobservable: Coronal Line Data from NLS1s as a Test of


  We have measured coronal line emission for a sample of 19 Narrow-Line
Seyfert~1 galaxies. Kinematic analysis shows that the Coronal Line Region (CLR)
consists of gas in a decelerating outflow.
  We intend to use these data as a test of the EUV emission of NLS1s. By
comparison with photoionization modelling for a number of power-law + black
body spectra, we plan to deduce the most likely EUV continua for these objects
as well as explore physical conditions in the CLR.

</DOC>
<DOC>
<DOCNO> 120469 </DOCNO>
The highly polarized open cluster Trumpler 27


  We have carried out multicolor linear polarimetry (UBVRI) of the brightest
stars in the area of the open cluster Trumpler 27. Our data show a high level
of polarization in the stellar light with a considerable dispersion, from $P =
4%$ to $P = 9.5%$. The polarization vectors of the cluster members appear to be
aligned. Foreground polarization was estimated from the data of some non-member
objects, for which two different components were resolved: the first one
associated with a dust cloud close to the Sun producing $P_{\lambda max}=1.3%$
and $\theta=146$ degrees, and a second component, the main source of
polarization for the cluster members, originated in another dust cloud, which
polarizes the light in the direction of $\theta= 29.5$ degrees. From a detailed
analysis, we found that the two components have associated values $E_{B-V} <
0.45 $ for the first one, and $E_{B-V} > 0.75$ for the other. Due the
difference in the orientation of both polarization vectors, almost 90 degrees
(180 degrees at the Stokes representation), the first cloud ($\theta \sim 146$
degrees) depolarize the light strongly polarized by the second one ($\theta
\sim 29.5$ degrees).

</DOC>
<DOC>
<DOCNO> 169680 </DOCNO>
Preparation information and optimal decompositions for mixed quantum


  Consider a joint quantum state of a system and its environment. A measurement
on the environment induces a decomposition of the system state. Using
algorithmic information theory, we define the preparation information of a pure
or mixed state in a given decomposition. We then define an optimal
decomposition as a decomposition for which the average preparation information
is minimal. The average preparation information for an optimal decomposition
characterizes the system-environment correlations. We discuss properties and
applications of the concepts introduced above and give several examples.

</DOC>
<DOC>
<DOCNO> 68954 </DOCNO>
Different Hagedorn temperatures for mesons and baryons from experimental


  We analyze the light-flavor particle mass spectra and show that in the region
up to ~1.8GeV the Hagedorn temperature for baryons is about 30% smaller than
for mesons, reflecting the fact that the number of baryon states grows more
rapidly with the mass. We also show that the spectra are well reproduced in a
model where hadrons are compound objects of quanta, whose available number
increases with mass. The rapid growth of number of hadronic states is a
combinatorial effect. We also point out that an upper limit on the excitation
energy of these quanta results in a maximum number of hadron states that can be
formed. According to this combinatorial saturation, no more light-flavor hadron
resonances exist above a certain mass.

</DOC>
<DOC>
<DOCNO> 11207 </DOCNO>
Understanding conserved amino acids in proteins


  It has been conjectured that evolution exerted pressure to preserve amino
acids bearing thermodynamic, kinetic, and functional roles. In this letter we
show that the physical requirement to maintain protein stability gives rise to
a sequence conservatism pattern that is in remarkable agreement with that found
in natural proteins. Based on the physical properties of amino acids, we
propose a model of evolution that explains conserved amino acids across protein
families sharing the same fold.

</DOC>
<DOC>
<DOCNO> 85116 </DOCNO>
Quantum Gravity at Very High Energies


  The problem of time and the quantization of three dimensional gravity in the
strong coupling regime is studied following path integral methods. The time is
identified with the volume of spacetime. We show that the effective action
describes an infinite set of massless relativistic particles moving in a curved
three-dimensional target space, i.e. a tensionless 3-brane on a curved
background. If the cosmological constant is zero the target space is flat and
there is no ` ` graviton" propagation (i.e., $G[g_{ij} (2), g_{ij} (1)] = 0$).
If the cosmological constant is different from zero, 3D gravity is both
classical and quantum mechanically soluble. Indeed, we find the following
results: i) The general exact solutions of the Einstein equations are singular
at $t=0$ showing the existence of a big-bang in this regime and ii) the
propagation amplitude between two geometries $<g_{ij} (2), t_2| g_{ij} (1),
t_1>$ vanishes as $t \to 0$, suggesting that big-bang is suppressed quantum
mechanically. This result is also valid for $D>3$.

</DOC>
<DOC>
<DOCNO> 70622 </DOCNO>
Moduli fields and brane tensions: generalizing the junction conditions


  Taking the Randall-Sundrum models as background scenario, we derive
generalized Israel-Lanczos-Sen thin-shell junction conditions for systems in
which several bulk scalar fields are non-minimally coupled to gravity. We
demonstrate that the form of the junction conditions (though arguably not the
physics) depends on the choice of frame. We show that generally (in any frame
except the Einstein frame) the presence of a thin shell induces discontinuities
in the normal derivative of the scalar field, even in the absence of any direct
interaction between the thin shell and the scalar field. For some exceptional
scalar field configurations the discontinuities in the derivatives of the
metric and the scalar fields can feed back into each other and so persist even
in the absence of any thin shell of stress-energy.

</DOC>
<DOC>
<DOCNO> 11862 </DOCNO>
Atomistics of Tensile Failure in Fused Silica: Weakest Link Models


  In weakest link models the failure of a single microscopic element of a
brittle material causes the failure of an entire macroscopic specimen, just as
a chain fails if one link fails. Pristine samples of glass, such as optical
communications fiber, approach their ideal strength, and their brittle tensile
failure has been described by this model. The statistics of weakest link models
are calculable in terms of the statistics of the individual links, which,
unfortunately, are poorly known. Use of the skewness of the failure
distribution may permit simultaneous determination of the statistics of the
individual weak links and of their number density, which indicates their
physical origin. However, the applicability of weakest link models to real
materials remains unproven.

</DOC>
<DOC>
<DOCNO> 117055 </DOCNO>
Second law versus variation principles


  Pontrjagin's extremum principle of control theory is applied to mechanics and
transfered to equilibrium thermodynamics in order to test it as an ansatz. This
approach allows to derive the grand partition function as result of a variation
problem with the Hamilton energy. Furthermore, the maximum entropy principle
can be derived and -last not least - the second law in a modified form.
Contrary to Clausius's version of second law, the derivation can predict second
law violations if potential fields are included into consideration. This
conclusion is supported indirectly by experimental data from literature. The
range of gain efficiency of a cylindric capacitance with a polymer solution as
dielectrics has been estimated to about some promille per cycle under optimal
conditions.

</DOC>
<DOC>
<DOCNO> 150783 </DOCNO>
Supersymmetric black hole solutions with $R^2$-interactions


  We present a class of static supersymmetric multi-center black hole solutions
arising in four-dimensional N=2 supergravity theories with terms quadratic in
the Weyl tensor. We also comment on possible corrections to the metric on the
moduli space of these black holes solutions.

</DOC>
<DOC>
<DOCNO> 13793 </DOCNO>
Low Energy Quasiparticle Excitation in the Vortex State of Borocarbide


  We have measured the low temperature heat capacity Cp and microwave surface
impedance Zs in the vortex state of YNi_2B_2C. In contrast to conventional
s-wave superconductors, Cp shows a nearly \sqrt H-dependence. This \sqrt
H-dependence persists even after the introduction of the columnar defects which
change the electronic structure of the vortex core regime dramatically and
strongly disturb the regular vortex lattice. On the other hand, flux flow
resistivity obtained from Zs is nearly proportional to H. Taken together, these
results indicate that the vortex state of YNi_2B_2C is fundamentally different
from the conventional s-wave counterparts, in that the delocalized
quasiparticle states around the vortex core play a much more important role,
similar to d-wave superconductors.

</DOC>
<DOC>
<DOCNO> 151088 </DOCNO>
Duality and Non-Commutative Gauge Theory


  We study the generalization of S-duality to non-commutative gauge theories.
For rank one theories, we obtain the leading terms of the dual theory by
Legendre transforming the Lagrangian of the non-commutative theory expressed in
terms of a commutative gauge field. The dual description is weakly coupled when
the original theory is strongly coupled if we appropriately scale the
non-commutativity parameter. However, the dual theory appears to be
non-commutative in space-time when the original theory is non-commutative in
space. This suggests that locality in time for non-commutative theories is an
artifact of perturbation theory.

</DOC>
<DOC>
<DOCNO> 120461 </DOCNO>
Avalanching and Self Organised Criticality, a paradigm for geomagnetic


  The characterization of global energy storage and release in the coupled
solar wind-magnetosphere system remains one of the fundamental problems of
space physics.Recently, it has been realised that a new paradigm in physics,
that of Self Organised Criticality (SOC) may encapsulate the mixing and merging
of flux on many scales in the magnetotail prompting bursty energy release and
reconfiguration. SOC is consistent with qualitative measures such as power law
power spectra and bursty bulk flows and with more quantitative tests such as
power law burst distributions in auroral indices and auroral optical activity.
Here, we present a careful classification of the broad range of systems that
fall under the general description of "SOC". We argue that some, but not all,
of these are consistent with our current understanding of the magnetosphere. We
discuss the observed low dimensionality of the dynamic magnetosphere in terms
of both SOC model properties, and observables. Observations of burst statistics
are highlighted; we show that these are currently suggestive but not sufficient
to confirm SOC and in particular we find that auroral indices are not effective
at distinguishing the internal dynamics of the magnetosphere from that of the
intermittent solar wind driver. This may also elucidate the paradox of
predictability and complexity of the coupled solar wind-magnetosphere system.

</DOC>
<DOC>
<DOCNO> 84180 </DOCNO>
Space-time uncertainty relation and Lorentz invariance


  We discuss a Lorentz covariant space-time uncertainty relation, which agrees
with that of Karolyhazy-Ng-van Dam when an observational time period delta t is
larger than the Planck time lp. At delta t < lp, this uncertainty relation
takes roughly the form delta t delta x > lp^2, which can be derived from the
condition prohibiting the multi-production of probes to a geometry. We show
that there exists a minimal area rather than a minimal length in the
four-dimensional case. We study also a three-dimensional free field theory on a
non-commutative space-time realizing the uncertainty relation. We derive the
algebra among the coordinate and momentum operators and define a
positive-definite norm of the representation space. In four-dimensional
space-time, the Jacobi identity should be violated in the algebraic
representation of the uncertainty relation.

</DOC>
<DOC>
<DOCNO> 118241 </DOCNO>
Is There a Detectable Vishniac Effect?


  The dominant linear contribution to cosmic microwave background (CMB)
fluctuations at small angular scales (less than one arcsec) is a second-order
contribution known as the Vishniac or Ostriker-Vishniac effect. This effect is
caused by the scattering of CMB photons off free electrons after the universe
has been reionized, and is dominated by linear perturbations near the R_V =2
Mpc/(h Gamma/0.2) scale in the Cold Dark Matter cosmogony. As the reionization
of the universe requires that nonlinear objects exist on some scale, however,
one can compare the scale responsible for reionization to R_V and ask if a
linear treatment is even feasible in different scenarios of reionization. For
an Omega_0 = 1 cosmology normalized to cluster abundances, only about 65% of
the linear integral is valid if reionization is due to quasars in halos of mass
10^9 solar, while 75% of the integral is valid if reionization was caused by
stars in 10^6 solar mass halos. In lambda or open cosmologies, both the
redshift of reionization and z_V are pushed further back, but still only 75% to
85% of the linear integral is valid, independent of the ionization scenario. We
point out that all odd higher-order moments from Vishniac fluctuations are zero
while even moments are non-zero, regardless of the gaussianity of the density
perturbations. This provides a defining characteristic of the Vishniac effect
that differentiates it from other secondary perturbations and may be helpful in
separating them.

</DOC>
<DOC>
<DOCNO> 118802 </DOCNO>
Asymptotic Giant Branch Stars in Interacting Galaxy Globular Clusters


  We present new modelling of the spectrophotometric properties of intermediate
age stellar populations in the near-infrared (NIR). We take into account the
evolutionary and spectroscopic properties of the Asymptotic Giant Branch (AGB)
stars which dominate the integrated NIR emission of those populations. The
predictions of spectrophotometric narrow-band molecular indices require the use
of an effective temperature -- colour (or spectrum) calibration for AGB stars;
synthetic indices show a strong dependence upon this calibration. Preliminary
results of NIR observations of a supermassive 500 Myr old stellar cluster in
the prototypical merger remnant NGC 7252 are presented. The spectra are indeed
consistent with intermediate age models dominated by light from AGB stars, a
significant fraction of which may be carbon rich. Implications for the stellar
inputs used in the modelling of intermediate age stellar populations and their
NIR emission are discussed.

</DOC>
<DOC>
<DOCNO> 120067 </DOCNO>
The Metallicity Distribution Function of Red Giants in the LMC


  We report new metallicity determinations for 39 red giants in a 220 square
arcminute region, 1.8 degrees southwest of the bar of the Large Magellanic
Cloud. These abundance measurements are based on spectroscopy of the Ca II
infrared triplet. The metallicity distribution function (MDF) shows a strong
peak at [Fe/H] = -0.57 +/- 0.04. Half the red giants in our field fall within
the range -0.83 < [Fe/H] < -0.41. We find a striking contrast in the shape of
the MDF below [Fe/H] < -1 between our inner disk field and the distant outer
field studied by Olszewski (1993). Our field-star MDF seems similar to that of
the intermediate-age (1-3 Gyr) star clusters. We have also obtained abundance
estimates using Stromgren photometry for ~1000 red giants in the same field.
The Stromgren measurements, which are sensitive to a combination of cyanogen
and iron lines, correlate well with the Ca II measurements, but a
metallicity-dependent offset is found (abridged).

</DOC>
<DOC>
<DOCNO> 152563 </DOCNO>
Behavior of Boundary String Field Theory Associated with Integrable


  We put forward an idea that the boundary entropy associated with integrable
massless flow of thermodynamic Bethe ansatz (TBA) is identified with tachyon
action of boundary string field theory. We show that the temperature
parameterizing a massless flow in the TBA formalism can be identified with
tachyon energy for the classical action at least near the ultraviolet fixed
point, i.e. the open string vacuum.

</DOC>
<DOC>
<DOCNO> 83431 </DOCNO>
Opportunity Cost Algorithms for Combinatorial Auctions


  Two general algorithms based on opportunity costs are given for approximating
a revenue-maximizing set of bids an auctioneer should accept, in a
combinatorial auction in which each bidder offers a price for some subset of
the available goods and the auctioneer can only accept non-intersecting bids.
Since this problem is difficult even to approximate in general, the algorithms
are most useful when the bids are restricted to be connected node subsets of an
underlying object graph that represents which objects are relevant to each
other. The approximation ratios of the algorithms depend on structural
properties of this graph and are small constants for many interesting families
of object graphs. The running times of the algorithms are linear in the size of
the bid graph, which describes the conflicts between bids. Extensions of the
algorithms allow for efficient processing of additional constraints, such as
budget constraints that associate bids with particular bidders and limit how
many bids from a particular bidder can be accepted.

</DOC>
<DOC>
<DOCNO> 151777 </DOCNO>
On Superpotentials for D-Branes in Gepner Models


  A large class of D-branes in Calabi-Yau spaces can be constructed at the
Gepner points using the techniques of boundary conformal field theory. In this
note we develop methods that allow to compute open string amplitudes for such
D-branes. In particular, we present explicit formulas for the products of open
string vertex operators of untwisted A-type branes. As an application we show
that the boundary theories of the quintic associated with the special
Lagrangian submanifolds Im \omega_i z_i = 0 where \omega_i^5=1 possess no
continuous moduli.

</DOC>
<DOC>
<DOCNO> 120136 </DOCNO>
The evolution of disk galaxies


  We study the evolution of disk galaxies using galaxy evolutionary models with
initial and boundary conditions linked to the hierarchical formation scenario.
Disks galaxies are modeled locally within growing cold dark matter halos and
including a physical model for star formation. We focus our attention on
predictions of the star formation history, size and surface brightness
evolution and the evolution of the H- and B-band Tully-Fisher relations.
Comparisons with available observational data are presented.

</DOC>
<DOC>
<DOCNO> 85120 </DOCNO>
Invariants of PL manifolds from metrized simplicial complexes.


  An invariant of three-dimensional orientable manifolds is built on the base
of a solution of pentagon equation expressed in terms of metric characteristics
of euclidean tetrahedra.

</DOC>
<DOC>
<DOCNO> 8402 </DOCNO>
Small-worlds: How and why


  We investigate small-world networks from the point of view of their origin.
While the characteristics of small-world networks are now fairly well
understood, there is as yet no work on what drives the emergence of such a
network architecture. In situations such as neural or transportation networks,
where a physical distance between the nodes of the network exists, we study
whether the small-world topology arises as a consequence of a tradeoff between
maximal connectivity and minimal wiring. Using simulated annealing, we study
the properties of a randomly rewired network as the relative tradeoff between
wiring and connectivity is varied. When the network seeks to minimize wiring, a
regular graph results. At the other extreme, when connectivity is maximized, a
near random network is obtained. In the intermediate regime, a small-world
network is formed. However, unlike the model of Watts and Strogatz (Nature {\bf
393}, 440 (1998)), we find an alternate route to small-world behaviour through
the formation of hubs, small clusters where one vertex is connected to a large
number of neighbours.

</DOC>
<DOC>
<DOCNO> 69938 </DOCNO>
Can R-parity violation explain the LSND data as well?


  The recent Super-Kamiokande data now admit only one type of mass hierarchy in
a framework with three active and one sterile neutrinos. We show that neutrino
masses and mixings generated by R-parity-violating couplings, with values
within their experimental upper limits, are capable of reproducing this
hierarchy, explaining all neutrino data particularly after including the LSND
results.

</DOC>
<DOC>
<DOCNO> 40465 </DOCNO>
O'Mega & WHIZARD: Monte Carlo Event Generator Generation For Future


  I describe the optimizing matrix element generator O'Mega and Wolfgang
Kilian's event generator generator WHIZARD. These tools cooperate in the
automated production of efficient unweighted event generators for linear
collider physics.

</DOC>
<DOC>
<DOCNO> 39788 </DOCNO>
Limits on a Composite Higgs Boson


  Precision electroweak data are generally believed to constrain the Higgs
boson mass to lie below approximately 190 GeV at 95% confidence level. The
standard Higgs model is, however, trivial and can only be an effective field
theory valid below some high energy scale characteristic of the underlying
non-trivial physics. Corrections to the custodial isospin violating parameter T
arising from interactions at this higher energy scale dramatically enlarge the
allowed range of Higgs mass. We perform a fit to precision electroweak data and
determine the region in the (m_H, Delta T) plane that is consistent with
experimental results. Overlaying the estimated size of corrections to T arising
from the underlying dynamics, we find that a Higgs mass up to 500 GeV is
allowed. We review two composite Higgs models which can realize the possibility
of a phenomenologically acceptable heavy Higgs boson. We comment on the
potential of improvements in the measurements of m_t and M_W to improve
constraints on composite Higgs models.

</DOC>
<DOC>
<DOCNO> 117271 </DOCNO>
Aircraft Hazard related to gas emission from the Earth


  I think it important that pilots, the aircraft industry, air safety staff,
accident investigators, should all be aware of the possibility of the hazard
described in the accompanying article, and also that research shold be directed
to establish the severity of this hazard, and find ways of diminishing the
risk.

</DOC>
<DOC>
<DOCNO> 70511 </DOCNO>
The Higgs Boson Might Not Couple To B Quarks


  We discuss an alternative version of the electroweak standard model, in which
only the heavy t quark, not the light fermions, couples to the Higgs boson with
a strength given by the standard model. The Higgs particle decays dominantly
into two gluons jets. The branching ratio for the 2 gamma decay is about 3.5%.
The Higgs particle would be a narrow object (width about 60 KeV), and its mass
might be consistent with the value given by typical estimates of radiative
effects measured by the LEP experiments.

</DOC>
<DOC>
<DOCNO> 150757 </DOCNO>
Tachyon couplings on non-BPS D-branes and Dirac-Born-Infeld action


  By explicit evaluation of certain disk S-matrix elements in the presence of
background B-flux, we find coupling of two open string tachyons to gauge field,
graviton, dilaton or Kalb-Ramond antisymmetric tensor on the world-volume of a
single non-BPS D$p$-brane. We then propose an extension of the abelian
Dirac-Born-Infeld action which naturally reproduces these couplings in field
theory. This action includes non-linearly the dynamics of the tachyon field
much like the other bosonic modes of the non-BPS D$p$-brane. On the general
grounds of gauge and T-duality transformations and the symmetrized trace
prescription, we then extend the abelian action to non-abelian cases.

</DOC>
<DOC>
<DOCNO> 117015 </DOCNO>
The Rolling Motion of a Disk on a Horizontal Plane


  Recent interest in the old problem of the motion of a coin spinning on a
tabletop has focused on mechanisms of dissipation of energy as the angle alpha
of the coin to the table decreases, while the angular velocity Omega of the
point of contact increases. Following a review of the general equations of
motion of a thin disk rolling without slipping on a horizontal surface, we
present results of simple experiment on the time dependence of the motion that
indicate the dominant dissipative power loss to be proportional to the Omega^2
up to and including the last observable cycle.

</DOC>
<DOC>
<DOCNO> 9569 </DOCNO>
A Pseudogap in the Single-Particle Density of States of a


  We study a single-particle density of states (DOS) in a model of
Tomonaga-Luttinger liquid with small (large) values of the Luttinger parameter
$K_\rc < 0.17$, ($K_\rc > 5.82$), in the charge sector. We explain that such
values of $K_\rc$ may be achieved by electron-phonon interactions without
generating the spin gap. We suggest that electron-phonon interactions can be
partially incorporated into the Tomonaga-Luttinger liquid scheme by introducing
frequency dependent $K_\rc(\omega)$. We demonstrate that when the low-frequency
asymptotic value $K_\rc(0) < 0.17$ or $K_\rc(0) > 5.82$, the single-particle
DOS has a pseudogap behavior in frequency where $\rho(\omega)/\omega$ vanishes
at small frequencies.
 The DOS exhibits a peak the position of which scales as $[K(0) +
K^{-1}(0)]\omega_0/2$ where $\omega_0$ is the characteristic phonon frequency.

</DOC>
<DOC>
<DOCNO> 151731 </DOCNO>
Derivative corrections to D-brane actions with constant background


  We study derivative corrections to the effective action for a single D-brane
in type II superstring theory coupled to constant background fields. In
particular, within this setting we determine the complete expression for the
(disk level) four-derivative corrections to the Born-Infeld part of the action.
We also determine 2n-form 2n-derivative corrections to the Wess-Zumino term.
Both types of corrections involve all orders of the gauge field strength, F.
The results are obtained via string sigma-model loop calculations using the
boundary state operator language. The corrections can be succinctly written in
terms of the Riemann tensor for a non-symmetric metric.

</DOC>
<DOC>
<DOCNO> 7621 </DOCNO>
Itinerant ferromagnetism in half-metallic CoS_2


  We have investigated electronic and magnetic properties of the pyrite-type
CoS_2 using the linearized muffin-tin orbital (LMTO) band method. We have
obtained the ferromagnetic ground state with nearly half-metallic nature. The
half-metallic stability is studied by using the fixed spin moment method. The
non-negligible orbital magnetic moment of Co 3d electrons is obtained as $\mu_L
= 0.06 \mu_B$ in the local spin density approximation (LSDA). The calculated
ratio of the orbital to spin angular momenta <L_z >/< S_z > = 0.15 is
consistent with experiment. The effect of the Coulomb correlation between Co 3d
electrons is also explored with the LSDA + U method. The Coulomb correlation at
Co sites is not so large, $U \lesssim 1$ eV, and so CoS_2 is possibly
categorized as an itinerant ferromagnet. It is found that the observed
electronic and magnetic behaviors of CoS_2 can be described better by the LSDA
than by the LSDA + U.

</DOC>
<DOC>
<DOCNO> 71447 </DOCNO>
The Utility of Quantum Field Theory


  This talk surveys a broad range of applications of quantum field theory, as
well as some recent developments. The stress is on the notion of effective
field theories. Topics include implications of neutrino mass and a possible
small value of $\sin(2\beta)$, supersymmetric extensions of the standard model,
the use of field theory to understand fundamental issues in string theory (the
problem of multiple ground states and the question: does string theory predict
low energy supersymmetry), and the use of string theory to solve problems in
field theory. Also considered are a new type of field theory, and indications
from black hole physics and the cosmological constant problem that effective
field theories may not completely describe theories of gravity.

</DOC>
<DOC>
<DOCNO> 68164 </DOCNO>
Recent progress in Affleck-Dine baryogenesis


  In the MSSM, cosmological scalar field condensates formed along flat
directions of the scalar potential (Affleck-Dine condensates) are typically
unstable with respect to formation of Q-balls, a type of non-topological
soliton. I discuss the creation and growth of the quantum seed fluctuations
which catalyse the collapse of the condensate. In D-term inflation models, the
fluctuations of squark fields in the flat directions also give rise to
isocurvature density fluctuations stored in the Affleck-Dine condensate. After
the condensate breaks up, these can be perturbations in the baryon number, or,
in the case where the present neutralino density comes directly from B-ball
decay, perturbations in the number of dark matter neutralinos. The latter case
results in a large enhancement of the isocurvature perturbation, which should
be observable by PLANCK.

</DOC>
<DOC>
<DOCNO> 70760 </DOCNO>
Gravitational Origin of Quark Masses in an Extra-Dimensional Brane World


  Using the warped extra dimension geometry of the many-brane extension of the
Randall-Sundrum solution, we find a natural explanation for the observed quark
masses of the three Standard Model (SM) generations. Localizing massless SM
matter generations on neighboring 3-branes in an extra dimensional world leads
to phenomenologically acceptable effective four dimensional masses arising from
the coupling of the fermion field with the background metric. Thus this
geometry can simultaneously address the gauge and quark mass hierarchy
problems.

</DOC>
<DOC>
<DOCNO> 9641 </DOCNO>
Interferencing in coupled Bose-Einstein condensates


  We consider an exactly soluble model of two Bose-Einstein condensates with a
Josephson-type of coupling. Its equilibrium states are explicitly found showing
condensation and spontaneously broken gauge symmetry. It is proved that the
total number and total phase fluctuation operators, as well as the relative
number and relative current fluctuation operators form both a quantum canonical
pair. The exact relation between the relative current and phase fluctuation
operators is established. Also the dynamics of these operators is solved
showing the collapse and revival phenomenon.

</DOC>
<DOC>
<DOCNO> 100607 </DOCNO>
A norm on homology of surfaces and counting simple geodesics


  We define a norm on homology of punctured tori equipped with a complete
hyperbolic metric of finite volume and use it to find asymptotics on the growth
of the number of simple geodesics of bounded length.

</DOC>
<DOC>
<DOCNO> 151384 </DOCNO>
A New Look on the Electromagnetic Duality. Suggestions and Developments


  In this paper a new look on the electro-magnetic duality is presented and
appropriately exploited. The duality analysis in the nonrelativistic and
relativistic formulations is shown to lead to the idea the mathematical model
field to be a differential form valued in the 2-dimensional vector space ${\cal
R}^2$. A full ${\cal R}^2$ covariance is achieved through introducing
explicitly the canonical complex structure ${\cal I}$ of ${\cal R}^2$ in the
nonrelativistic equations. The connection of the relativistic Hodge * with
${\cal I}$ is shown and a complete coordinate free relativistic form of the
equations and the conservative quantities is obtained. The duality symmetry is
interpreted as invariance of the conservative quantities and conservation
equations.

</DOC>
<DOC>
<DOCNO> 117089 </DOCNO>
Low-frequency method for magnetothermopower and Nernst effect


  We describe an AC method for the measurement of the longitudinal (Sxx) and
transverse (Sxy, i.e. Nernst) thermopower of mm-size single crystal samples at
low temperatures (T<1 K) and high magnetic fields (B>30 T). A low-frequency (33
mHz) heating method is used to increase the resolution, and to determine the
temperature gradient reliably in high magnetic fields. Samples are mounted
between two thermal blocks which are heated by a sinusoidal frequency f0 with a
p/2 phase difference. The phase difference between two heater currents gives a
temperature gradient at 2f0. The corresponding thermopower and Nernst effect
signals are extracted by using a digital signal processing method due. An
important component of the method involves a superconducting link, YBa2Cu3O7+d
(YBCO), which is mounted in parallel with sample to remove the background
magnetothermopower of the lead wires. The method is demonstrated for the quasi
two-dimensional organic conductor a-(BEDT-TTF)2KHg(SCN)4, which exhibits a
complex, magnetic field dependent ground state above 22.5 T at low
temperatures.

</DOC>
<DOC>
<DOCNO> 71595 </DOCNO>
Bosonization of QCD at high density


  We describe the color-flavor locking (CFL) color superconductor in terms of
bosonic variables, where the gaped quarks are realized as solitons, so-called
superqualitons. We then show that the ground state of the CFL color
superconductor is a $Q$-matter, which is the lowest energy state for a given
fixed baryon number. From this $Q$-matter, we calculate the minimal energy to
create a superqualiton and argue that it is twice of the Cooper gap. Upon
quantizing the zero modes of superqualitons, we find superqualitons have the
same quantum number as the gaped quarks and furthermore all the high spin
states of superqualitons are absent in the effective bosonic description of the
CFL color superconductor.

</DOC>
<DOC>
<DOCNO> 80599 </DOCNO>
Dirac operator index and topology of lattice gauge fields


  The fermionic topological charge of lattice gauge fields, given in terms of a
spectral flow of the Hermitian Wilson--Dirac operator, or equivalently, as the
index of Neuberger's lattice Dirac operator, is shown to have analogous
properties to L\"uscher's geometrical lattice topological charge. The main new
result is that it reduces to the continuum topological charge in the classical
continuum limit. (This is sketched here; the full proof will be given in a
sequel to this paper.) A potential application of the ideas behind fermionic
lattice topological charge to deriving a combinatorial construction of the
signature invariant of a 4-manifold is also discussed.

</DOC>
<DOC>
<DOCNO> 8652 </DOCNO>
Exact Meander Asymptotics: a Numerical Check


  This note addresses the meander enumeration problem: "Count all topologically
inequivalent configurations of a closed planar non self-intersecting curve
crossing a line through a given number of points". We review a description of
meanders introduced recently in terms of the coupling to gravity of a
two-flavored fully-packed loop model. The subsequent analytic predictions for
various meandric configuration exponents are checked against exact enumeration,
using a transfer matrix method, with an excellent agreement.

</DOC>
<DOC>
<DOCNO> 71419 </DOCNO>
New Formulas and Predictions for Running Fermion Masses at Higher Scales


  Including contributions of scale-dependent vacuum expectation values, we
derive new analytic formulas and obtain substantially different numerical
predictions for the running masses of quarks and charged-leptons at higher
scales in the SM, 2HDM and MSSM. These formulas exhibit significantly different
behaviours with respect to their dependence on gauge and Yukawa couplings than
those derived earlier. At one-loop level the masses of the first two
generations are found to be independent of Yukawa couplings of the third
generation in all the three effective theories in the small mixing limit.
Analytic formulas are also obtained for running $\tan\beta(\mu)$ in 2HDM and
MSSM. Other numerical analyses include study of the third generation masses at
high scales as functions of low-energy values of $\tan\beta$ and SUSY scale
$M_S=M_Z-10^4$ GeV.

</DOC>
<DOC>
<DOCNO> 100392 </DOCNO>
Finite Groups Embeddable in Division Rings


  Finite groups that are embeddable in the multiplicative groups of division
rings $K$ were completely determined by S. A. Amitsur in 1955. In case $K$ has
characteristic $p>0$, the only possible finite subgroups of $K^*$ are cyclic
groups, according to a theorem of I. N. Herstein. Thus, the only interesting
case is when $K$ has characteristic 0; that is, when $K\supseteq {\Bbb Q}$.
  Herstein conjectured that odd-order subgroups of division rings $K$ were
cyclic, and he proved this to be the case when $K$ is the division ring of the
real quaternions. Herstein's conjecture was settled negatively by Amitsur. As
part of his complete classification of finite groups in division rings, Amitsur
showed that the smallest noncyclic odd-order group that can be embedded in a
division ring is one of order 63 (and this group is unique).
  Amitsur's paper is daunting to read as it is long and technically
complicated. In lecturing to a graduate class on division rings, I tried to
find a simple reason for the ``first exceptional odd order'' 63 (to Herstein's
conjecture). After some work, I did come up with a reason that was simple
enough to be explained to my class, without having to go through any part of
Amitsur's paper. Furthermore, the method I used led easily to the second
exceptional odd order, 117 (which was not mentioned in Amitsur's paper). Since
this line of reasoning did not seem to have appeared in the literature before,
I record it in this short note. To better motivate the results discussed here,
I have also included a quick exposition on the beginning part of the theory of
finite subgroups of division rings.

</DOC>
<DOC>
<DOCNO> 123064 </DOCNO>
On the broadening of emission lines in active galactic nuclei


  Recent works, both theoretical and observational, have suggested that
turbulence could play a non-negligible role in the broadening of emission lines
in active galactic nuclei. The purpose of this note is to show how shock
wave-turbulence interaction, under unsteady regime, can affect the broadening
of emission lines.

</DOC>
<DOC>
<DOCNO> 121783 </DOCNO>
Lensing in the Hercules Supercluster


  We report Keck LRIS observations of an arc-like background galaxy near the
center of Abell 2152 (z=0.043), one of the three clusters comprising the
Hercules supercluster. The background object has a redshift z=0.1423 and is
situated 25 arcsec north of the primary component of the A2152 brightest
cluster galaxy (BCG). The object is about 15 arcsec in total length and has a
reddening-corrected R-band magnitude of $m_R = 18.55\pm0.03$. Its spectrum
shows numerous strong emission lines, as well as absorption features. The
strength of the H-alpha emission would imply a star formation rate $\SFR
\approx 3h^{-2} \msun $yr$^{-1}$ in the absence of any lensing. However, the
curved shaped of this object and its tangential orientation along the major
axis of the BCG suggest lensing. We model the A2152 core mass distribution
including the two BCG components and the cluster potential. We present velocity
and velocity dispersion profile measurements for the two BCG components and use
these to help constrain the potential. The lens modeling indicates a likely
magnification factor of $\sim1.9$ for the lensed galaxy, making A2152 the
nearest cluster in which such significant lensing of a background source has
been observed. Finally, we see evidence for a concentration of early-type
galaxies at $z=0.13$ near the centroid of the X-ray emission previously
attributed to A2152. We suggest that emission from this background
concentration is the cause of the offset of the X-ray center from the A2152
BCG. The background concentration and the dispersed mass of the Hercules
supercluster could add further to the lensing strength of the A2152 cluster.

</DOC>
<DOC>
<DOCNO> 13112 </DOCNO>
The impact of two-dimensional elastic disk


  The impact of a two-dimensional elastic disk with a wall is numerically
studied. It is clarified that the coefficient of restitution (COR) decreases
with the impact velocity. The result is not consistent with the recent
quasi-static theory of inelastic collisions even for very slow impact. The
abrupt drop of COR is found due to the plastic deformation of the disk, which
is assisted by the initial internal motion.(to be published in J. Phys. Soc.
Jpn.)

</DOC>
<DOC>
<DOCNO> 14017 </DOCNO>
Mode-locking in ac-driven vortex lattices with random pinning


  We find mode-locking steps in simulated current-voltage characteristics of
ac-driven vortex lattices with {\it random} pinning. For low frequencies there
is mode-locking above a finite ac force amplitude, while for large frequencies
there is mode-locking for any small ac force. This is correlated with the
nature of temporal order in the different regimes in the absence of ac drive.
The mode-locked state is a frozen solid pinned in the moving reference of
frame, and the depinning from the step shows plastic flow and hysteresis.

</DOC>
<DOC>
<DOCNO> 10435 </DOCNO>
Influence of defects on the critical behaviour at the \boldmath{105} K


  The critical fluctuations in SrTiO$_3$ near its $105 K$ structural phase
transition were studied with triple axis diffractometry using high energy ($\ge
100 keV$) synchrotron radiation in different SrTiO$_3$ crystals with different
oxygen vacancy concentrations. Due to the presence of oxygen vacancies the
critical behaviour is changed compared to defect-free systems. In our
experiments a smearing out of the squared order parameter and a crossover of
the critical exponents $\nu$ and $\gamma$ above the phase transition
temperature is observed, with the crossover temperature strongly depending on
the concentration of the defects. To understand the experimental findings, e.g.
the unusual values for the critical exponents found near the critical
temperature, the Ginzburg-Landau-Wilson functional for structural phase
transitions in disordered systems was analyzed using renormalization group
theory and the replica trick. Considering the effects of defects which locally
increase the transition temperature leads to a qualitative understanding of the
observed behaviour. The crossover behaviour of the critical exponents can be
modeled and a quantitative analysis of the observed experimental data is
presented.

</DOC>
<DOC>
<DOCNO> 118423 </DOCNO>
HST Observations of the Wolf-Rayet Nebula NGC 6888


  We present Hubble Space Telescope WFPC2 images of a portion of the bright
northeast rim of NGC 6888, the nebular shell physically associated with the
Wolf-Rayet star HD 192163. The exposures are taken in the light of Halpha 6563,
[O III] 5007, and [S II] 6717,6731. The images are used to constrain models of
the ionization structure of nebular features. From these models we infer
physical conditions within features, and estimate elemental abundances within
the nebula. The results of our analysis, together with the degree of small
scale inhomogeneity apparent in the images, call into question the assumptions
underlying traditional methodologies for interpretation of nebular
spectroscopy.
  The thermal pressure of photoionized clumps is higher than the inferred
internal pressure of the shocked stellar wind, implying that the current
physical conditions have changed significantly over less than a few thousand
years. These results are discussed within the context of published three-wind
evolutionary scenarios for the formation of the nebula. We also discuss the
nature of a back-illuminated radiative shock driven into the cavity surrounding
NGC 6888.

</DOC>
<DOC>
<DOCNO> 178675 </DOCNO>
Electro-weak Reactions for Astrophysics


  The status of "ab initio" microscopic calculations of the 2H(p,gamma)3He and
3He(p,e+nu_e)4He reactions is reviewed. The methods used to generate accurate
nuclear ground- and scattering-state wave functions, and to construct realistic
electro-weak transition operators are described. The uncertainties in the
theoretical predictions, particularly those relevant to the p-3He weak capture,
are discussed. For the dp radiative capture, the theoretical results are
compared with the TUNL data in the energy range 0--100 keV.

</DOC>
<DOC>
<DOCNO> 119613 </DOCNO>
Semi analytic approach to understanding the distribution of neutral


  Analytic derivations of the correlation function and the column density
distribution for neutral hydrogen in the IGM are presented, assuming that the
non-linear baryonic mass density distribution in the IGM is lognormal. This
ansatz was used earlier by Bi & Davidsen (1997) to perform 1D simulations of
lines-of-sight and analyse the properties of absorption systems. Our approach
is completely analytic, which allows us to explore a wide region of the
parameter space for our model. The analytic results have been compared with
observations, whenever possible. Two kinds of correlation functions are
defined: along the line-of-sight (LOS) and across the transverse direction. We
find that the effects on the LOS correlation due to change in cosmology and the
slope of the equation of state of the IGM, \gamma are of the same order, which
means that we cannot constrain both the parameters simultaneously. However, it
is possible to constrain \gamma and its evolution using the observed LOS
correlation function at different epochs, provided one knows the background
cosmology. We suggest that the constraints on the evolution of \gamma obtained
using the LOS correlation can be used as an independent tool to probe the
reionisation history of the universe. From the transverse correlation function,
we find that the excess probability, over random, of finding two neutral
hydrogen overdense regions separated by an angle \theta, is always less than 1
per cent for redshifts greater than 2. Our models also reproduce the observed
column density distribution for neutral hydrogen and the shape of the
distribution depends on \gamma. Our calculations suggest that one can rule out
\gamma > 1.6 for z \simeq 2.31 using the column density distribution. However,
one cannot rule higher values of \gamma at higher redshifts.

</DOC>
<DOC>
<DOCNO> 100339 </DOCNO>
Exterior differentials of higher order and their covariant


  We investigate a particular realization of generalized q-differential
calculus of exterior forms on a smooth manifold based on the assumption that
the N-th power (N>2) of exterior differential is equal to zero. It implies the
existence of cyclic commutation relations for the differentials of first order
and their generalization for the differentials of higher order. Special
attention is paid to the cases N=3 and N=4. A covariant basis of the algebra of
such q-grade forms is introduced, and the analogues of torsion and curvature of
higher order are considered. We also study a graded exterior calculus on a
generalized Clifford algebra.

</DOC>
<DOC>
<DOCNO> 84483 </DOCNO>
Non-existence of radiation damping of gravitational motions


  A rigorous, non-perturbative proof that there is no radiation damping of
gravitational motions.

</DOC>
<DOC>
<DOCNO> 8391 </DOCNO>
Scaling analysis of the magnetic-field-tuned quantum transition in


  We have studied the magnetic-field-tuned superconductor-insulator quantum
transition (SIT) in amorphous In-O films with different oxygen content and,
hence, different electron density. While for states of the film near the
zero-field SIT the two-dimensional scaling behaviour is confirmed, for deeper
states in the superconducting phase the SIT scenario changes: in addition to
the scaling function that describes the conductivity of fluctuation-induced
Cooper pairs, there emerges a temperature-dependent contribution to the film
resistance. This contribution can originate from the conductivity of normal
electrons.

</DOC>
<DOC>
<DOCNO> 83325 </DOCNO>
Entrenchment Relations: A Uniform Approach to Nonmonotonicity


  We show that Gabbay's nonmonotonic consequence relations can be reduced to a
new family of relations, called entrenchment relations. Entrenchment relations
provide a direct generalization of epistemic entrenchment and expectation
ordering introduced by Gardenfors and Makinson for the study of belief revision
and expectation inference, respectively.

</DOC>
<DOC>
<DOCNO> 178698 </DOCNO>
Hadron structure after 25 years of QCD


  We briefly review the status of our understanding of hadron structure based
on QCD. This includes the role of symmetries, especially chiral symmetry, and
the insights provided by lattice QCD. The main focus is on baryon structure and
especially the nucleon, but this cannot be treated realistically without
reference to spectroscopy. Our aim is to highlight recent insights and
promising directions for future work.

</DOC>
<DOC>
<DOCNO> 101088 </DOCNO>
Pseudo-slice knots


  For n >1, if the Seifert form of a knotted 2n-1 sphere K in S^{2n+1} has a
metabolizer, then the knot is slice. Casson and Gordon proved that this is
false in dimension three (n = 1). However, in the three dimensional case it is
true that if the metabolizer has a basis represented by a strongly slice link
then K is slice. The question has been asked as to whether it is sufficient
that each basis element is represented by a slice knot to assure that K is
slice. For genus one knots this is of course true; here we present a genus two
counterexample.

</DOC>
<DOC>
<DOCNO> 71742 </DOCNO>
Meson twist-4 parton distributions in terms of twist-2 distribution


  We show that in the large N_c limit four-quark twist-4 distributions in the
pion can be expressed in terms of twist-2 pion distribution amplitude. This
allows us to compute the isospin-2 structure function of the pion
F_2^{I=2}(x_B) in the large N_c limit. The method can be easily applied to
other mesons as well.

</DOC>
<DOC>
<DOCNO> 101549 </DOCNO>
Perturbation of Domain: Singular Riemannian Manifolds


  We study a class of Riemannian manifolds which are equipped with a singular
metric. In particular we study a domain perturbation problem for the Dirichlet
eigenvalues which depends on the best constant in the Hardy Inequality.
However, we show that for these manifolds the constant is such that existing
theorems cannot be applied and then prove better estimates that overcome this.
Finally we set up an example that can be used to show that our results are
optimal. The methods for doing this final step are contained in another paper
in a more general ode setting.

</DOC>
<DOC>
<DOCNO> 11524 </DOCNO>
Phase diagram of the quarter-filled extended Hubbard model on a two-leg


  We investigate the ground-state phase diagram of the quarter-filled Hubbard
ladder with nearest-neighbor Coulomb repulsion V using the Density Matrix
Renormalization Group technique. The ground-state is homogeneous at small V, a
``checkerboard'' charge--ordered insulator at large V and not too small on-site
Coulomb repulsion U, and is phase-separated for moderate or large V and small
U. The zero-temperature transition between the homogeneous and the
charge-ordered phase is found to be second order. In both the homogeneous and
the charge-ordered phases the existence of a spin gap mainly depends on the
ratio of interchain to intrachain hopping. In the second part of the paper, we
construct an effective Hamiltonian for the spin degrees of freedom in the
strong-coupling charge-ordered regime which maps the system onto a frustrated
spin chain. The opening of a spin gap is thus connected with spontaneous
dimerization.

</DOC>
<DOC>
<DOCNO> 40659 </DOCNO>
Diffractive Dijet and 3-Jet Electroproduction at HERA


  A new H1 measurement of diffractive dijet and 3-jet production cross sections
in diffractive deep inelastic scattering events of the type ep->eXY is
presented. The data constrain well the diffractive gluon distribution. At low
x-pom, a calculation based on perturbative QCD is in a reasonable agreement
with the data.

</DOC>
<DOC>
<DOCNO> 102455 </DOCNO>
D-branes, Categories and N=1 Supersymmetry


  We show that boundary conditions in topological open string theory on
Calabi-Yau manifolds are objects in the derived category of coherent sheaves,
as foreseen in the homological mirror symmetry proposal of Kontsevich. Together
with conformal field theory considerations, this leads to a precise criterion
determining the BPS branes at any point in CY moduli space, completing the
proposal of Pi-stability.

</DOC>
<DOC>
<DOCNO> 13374 </DOCNO>
Quantum Hall Ferromagnetism in a Two-Dimensional Electron System


  Experiments on a nearly spin degenerate two-dimensional electron system
reveals unusual hysteretic and relaxational transport in the fractional quantum
Hall effect regime. The transition between the spin-polarized (with fill
fraction $\nu = 1/3$) and spin-unpolarized ($\nu = 2/5$) states is accompanied
by a complicated series of hysteresis loops reminiscent of a classical
ferromagnet. In correlation with the hysteresis, magnetoresistance can either
grow or decay logarithmically in time with remarkable persistence and does not
saturate. In contrast to the established models of relaxation, the relaxation
rate exhibits an anomalous divergence as temperature is reduced. These results
indicate the presence of novel two-dimensional ferromagnetism with a
complicated magnetic domain dynamic.

</DOC>
<DOC>
<DOCNO> 178575 </DOCNO>
Non-extensive statistics effects in quark-gluon plasma and in


  The presence of memory effects and color long-range forces among the
many-parton system in the early stage of heavy-ion collisions can affect the
particle statistical behavior at the freeze-out temperature. In this context,
we calculate, in the framework of the equilibrium generalized non-extensive
thermostatistics, the shape of pion transverse mass spectrum and the value of
the transverse momentum correlation function of the pions emitted during the
central Pb+Pb collisions and we show that the experimental results is well
reproduced assuming very small deviations from the standard statistics.

</DOC>
<DOC>
<DOCNO> 7672 </DOCNO>
^{27}Al Impurity-Satellite NMR and Non-Fermi-Liquid Behavior in


  Non-Fermi-liquid (NFL) behavior in the f-sublattice-diluted alloy system
U_{1-x}Th_xPd_2Al_3 has been studied using ^{27}Al nuclear magnetic resonance
(NMR). Impurity satellites due to specific U near-neighbor configurations to
^{27}Al sites are clearly resolved in both random and field-aligned powder
samples. The spatial mean Kbar and rms spread delta K of impurity satellite
shifts, which are related to the mean chibar and rms spread delta chi of the
inhomogeneous susceptibility, have been measured in field-aligned powders with
the crystalline c axis both perpendicular and parallel to the external field.
The relatively narrow lines observed at low temperatures suggest that disorder-
induced inhomogeneity of the f-ion--conduction-electron hybridization is not
the cause of NFL behavior in these alloys: at low temperatures the experimental
values of delta chi(T)/chibar(T) are much smaller than required by disorder-
driven models. This is in contrast to results in at least some alloys with
disordered non-f-ion nearest neighbors to f ions ("ligand disorder"), where
disorder-driven theories give good accounts of NFL behavior. Our results
suggest that f-ion dilution does not produce as much inhomogeneity of the
hybridization strength as substitution on ligand sites.

</DOC>
<DOC>
<DOCNO> 123298 </DOCNO>
3EG J2016+3657: Confirming an EGRET Blazar Behind the Galactic Plane


  We recently identified the blazar-like radio source G74.87+1.22 (B2013+370)
as the counterpart of the high-energy gamma-ray source 3EG J2016+3657 in the
Galactic plane. However, since most blazar identifications of EGRET sources are
only probabilistic in quality even at high Galactic latitude, and since there
also exists a population of unidentified Galactic EGRET sources, we sought to
obtain additional evidence to support our assertion that 3EG J2016+3657 is a
blazar. These new observations consist of a complete set of classifications for
the 14 brightest ROSAT X-ray sources in the error circle, of which B2013+370
remains the most likely source of the gamma-rays. We also obtained further
optical photometry of B2013+370 itself which shows that it is variable,
providing additional evidence of its blazar nature. Interestingly, this field
contains, in addition to the blazar, the plerionic supernova remnant CTB 87,
which is too distant to be the EGRET source, and three newly discovered
cataclysmic variables, all five of these X-ray sources falling within 16' of
each other. This illustrates the daunting problem of obtaining complete
identifications of EGRET sources in the Galactic plane.

</DOC>
<DOC>
<DOCNO> 170241 </DOCNO>
Gravitationally induced transition to classical behavior above 10^10


  The localization length for the center of mass motion of a matter lump,
induced by gravitation, is obtained, without using any phenomenological
constants. Its dependence from mass and volume is consistent both with unitary
evolution of microscopic particles and with the classical behavior of
macroscopic bodies required to account for wave function collapse in quantum
measurements, the transition between the two regimes being rather sharp. The
gravitational interaction of nonrelativistic matter is modelled by a Yukawa
Hamiltonian with vanishing pion mass, no gravitational background is needed and
the only hypothesis consists in assuming unentanglement between matter and the
Yukawa field.

</DOC>
<DOC>
<DOCNO> 8606 </DOCNO>
$1/f^{\alpha}$ fluctuations in a ricepile model


  The temporal fluctuation of the average slope of a ricepile model is
investigated. It is found that the power spectrum $S(f)$ scales as
$1/f^{\alpha}$ with $\alpha\approx 1.3$ when grains of rice are added only to
one end of the pile. If grains are randomly added to the pile, the power
spectrum exhibits $1/f^2$ behaviour. The profile fluctuations of the pile under
different driving mechanisms are also discussed.

</DOC>
<DOC>
<DOCNO> 121773 </DOCNO>
The Observed Offset Distribution of Gamma-Ray Bursts from Their Host


  We present a comprehensive study to measure the locations of gamma-ray bursts
(GRBs) relative to their host galaxies. In total, we find the offsets of 20
long-duration GRBs from their apparent host galaxy centers utilizing
ground-based images from Palomar and Keck and space-based images from the
Hubble Space Telescope (HST). The median projected angular (physical) offset is
0.17 arcsec (1.3 kpc). The median offset normalized by the individual host
half-light radii is 0.98 suggesting a strong connection of GRB locations with
the UV light of their hosts. This provides strong observational evidence for
the connection of GRBs to star formation. We compare the observed offset
distribution with an exponential disk, a model for the location of collapsars.
The statistical comparison shows good agreement, with the Kolmogorov-Smirnov
probability that the observed offsets derive from the model distribution of
P_KS = 0.45. We also compare the observed GRB offsets with the expected offset
distribution of delayed merging remnant progenitors (black hole--neutron star
and neutron star--neutron star binaries). We find that delayed merging remnant
progenitors, insofar as the predicted offset distributions from population
synthesis studies are representative, can be ruled out at the 2 x 10^{-3}
level. This is arguably the strongest observational constraint yet against
delayed merging remnants as the progenitors of long-duration GRBs. In the
course of this study, we have also discovered the putative host galaxies of GRB
990510 and GRB 990308 in archival HST data. (abstract abridged)

</DOC>
<DOC>
<DOCNO> 71653 </DOCNO>
Nucleon scattering with higgsino and wino cold dark matter


  Neutralinos that are mostly wino or higgsino are shown to be compatible with
the recent DAMA annual modulation signal. The nucleon scattering rates for
these dark matter candidates are typically an order of magnitude above the
oft-considered bino. Although thermal evolution of higgsino and wino number
densities in the early universe implies that they are not viable dark matter
candidates, non-thermal sources, such as from gravitino or moduli decay in
anomaly mediated supersymmetry breaking, suggest that they can be the dominant
source of cold dark matter. Their stealthiness at high energy colliders gives
even more impetus to analyze nucleon scattering detection methods. We also
present calculations for their predicted scattering rate with Germanium
detectors, which have yet to see evidence of WIMP scattering.

</DOC>
<DOC>
<DOCNO> 122676 </DOCNO>
The XMM/Megacam-VST/VIRMOS Large Scale Structure Survey


  The objective of the XMM-LSS Survey is to map the large scale structure of
the universe, as highlighted by clusters and groups of galaxies, out to a
redshift of about 1, over a single 8x8 sq.deg. area. For the first time, this
will reveal the topology of the distribution of the deep potential wells and
provide statistical measurements at truly cosmological distances. In addition,
clusters identified via their X-ray properties will form the basis for the
first uniformly-selected, multi-wavelength survey of the evolution of clusters
and individual cluster galaxies as a function of redshift. The survey will also
address the very important question of the QSO distribution within the cosmic
web.

</DOC>
<DOC>
<DOCNO> 83476 </DOCNO>
Semantic interpretation of temporal information by abductive inference


  Besides temporal information explicitly available in verbs and adjuncts, the
temporal interpretation of a text also depends on general world knowledge and
default assumptions. We will present a theory for describing the relation
between, on the one hand, verbs, their tenses and adjuncts and, on the other,
the eventualities and periods of time they represent and their relative
temporal locations.
  The theory is formulated in logic and is a practical implementation of the
concepts described in Ness Schelkens et al. We will show how an abductive
resolution procedure can be used on this representation to extract temporal
information from texts.

</DOC>
<DOC>
<DOCNO> 7986 </DOCNO>
Magnetic excitations in coupled Haldane spin chains near the quantum


  Two quasi-1-dimensional S=1 quantum antiferromagnetic materials, PbNi2V2O8
and SrNi2V2O8, are studied by inelastic neutron scattering on powder samples.
While magnetic interactions in the two systems are found to be very similar,
subtle differences in inter-chain interaction strengths and magnetic anisotropy
are detected. The latter are shown to be responsible for qualitatively
different ground state properties: magnetic long-range order in SrNi2V2O8 and
disordered ``spin liquid'' Haldane-gap state in PbNi2V2O8.

</DOC>
<DOC>
<DOCNO> 99394 </DOCNO>
Integer Sequences associated with Integer Monic Polynomial


  To every integer monic polynomial of degree m can be associated m integer
sequences having interesting properties to the roots of the polynomial. These
sequences can be used to find the real roots of any integer monic polynomial by
using recursion relation involving integers only. This method is faster than
the conventional methods using floating point arithmetic.

</DOC>
<DOC>
<DOCNO> 68833 </DOCNO>
Dynamical Quark Effects on Light Quark Masses


  We present results for light quark masses from a systematic lattice QCD study
with two degenerate flavors of dynamical quarks. Simulations are made with a
renormalization-group improved gauge action and a mean-field improved clover
quark action for sea quark masses corresponding to $m_{\rm PS}/m_{\rm V}
\approx 0.8$--0.6 and the lattice spacing $a=0.22$--0.11 fm. In the continuum
limit we find $m_{ud}^{\bar{MS}}(2 {\rm GeV})=3.44^{+0.14}_{-0.22}$ MeV using
the $\pi$ and $\rho$ meson masses as physical input, and $m_s^{\bar{MS}}(2 {\rm
GeV})=88^{+4}_{-6}$ MeV or $90^{+5}_{-11}$ MeV with the $K$ or $\phi$ meson
mass as additional input. The quoted errors represent statistical and
systematic combined, the latter including those from continuum and chiral
extrapolations, and from renormalization factors. Compared to quenched results,
two flavors of dynamical quarks reduce quark masses by about 25%.

</DOC>
<DOC>
<DOCNO> 150748 </DOCNO>
Action with Manifest Duality for Maximally Supersymmetric


  We perform explicitly the toroidal compactification of eleven dimensional
supergravity to six dimensions and present its action in a manifestly
$SO(5,5)\over SO(5)\times SO(5)$ invariant form using the recently proposed
covariant formulation of theories involving chiral fields.

</DOC>
<DOC>
<DOCNO> 151628 </DOCNO>
Are Rindler Quanta Real? Inequivalent particle concepts in quantum field


  Philosophical reflection on quantum field theory has tended to focus on how
it revises our conception of what a particle is. However, there has been
relatively little discussion of the threat to the "reality" of particles posed
by the possibility of inequivalent quantizations of a classical field theory,
i.e., inequivalent representations of the algebra of observables of the field
in terms of operators on a Hilbert space. The threat is that each
representation embodies its own distinctive conception of what a particle is,
and how a "particle" will respond to a suitably operated detector. Our main
goal is to clarify the subtle relationship between inequivalent representations
of a field theory and their associated particle concepts. We also have a
particular interest in the Minkowski versus Rindler quantizations of a free
Boson field, because they respectively entail two radically different
descriptions of the particle content of the field in the very same region of
spacetime. We shall defend the idea that these representations provide
complementary descriptions of the same state of the field against the claim
that they embody completely incommensurable theories of the field.

</DOC>
<DOC>
<DOCNO> 102673 </DOCNO>
On the number of square integrable solutions and self-adjointness of


  The main purpose of this paper is to investigate the formal deficiency
indices ${\cal N}_{\pm}(I)$ of a symmetric first order system $$ Jf'+Bf=\lambda
{\cal H} f $$ on an interval $I$, where $I=\mathbb{R}$ or $I=\mathbb{R}_\pm.$
Here $J,B,{cal H}$ are $n\times n$ matrix valued functions and the Hamiltonian
${\cal H}\ge 0$ may be singular even everywhere. We obtain two results for such
a system to have minimal numbers ${\cal N}_\pm(\mathbb{R})=0$ (resp. ${\cal
N}_\pm(\mathbb{R}_\pm)=n$) and a criterion for their maximality ${\cal
N}_{\pm}(\mathbb{R}_+)=2n.$ Some conditions for a canonical system to have
intermediate numbers ${\cal N}_\pm(\mathbb{R}_+)$ are presented, too. We also
obtain a generalization of the well-known Titchmarsh-Sears theorem for second
order Sturm-Liouville type equations. This contains results due to Lidskii and
Krein as special cases.
  It is important to note that in general the above system does not give rise
to an operator but rather to a symmetric linear relation in a Hilbert space.
These relations are investigated in detail.
  As a byproduct we obtain very short proofs of (generalizations of) the main
results of a paper by Kogan and Rofe-Beketov (Proc. Roy. Soc. Edinb. 74
(1974/75))as well as a criterion for the quasi-regularity of canonical systems.
This covers the Kac-Krein theorem and some results from the quoted paper of
Kogan and Rofe-Beketov.

</DOC>
<DOC>
<DOCNO> 11583 </DOCNO>
Fracture and second-order phase transitions


  Using the global fiber bundle model as a tractable scheme of progressive
fracture in heterogeneous materials, we define the branching ratio in
avalanches as a suitable order parameter to clarify the order of the phase
transition occurring at the collapse of the system. The model is analyzed using
a probabilistic approach suited to smooth fluctuations. The branching ratio
shows a behavior analogous to the magnetization in known magnetic systems with
2nd-order phase transitions. We obtain a universal critical exponent
$\beta\approx 0.5$ independent of the probability distribution used to assign
the strengths of individual fibers.

</DOC>
<DOC>
<DOCNO> 12584 </DOCNO>
Feasibility of biepitaxial YBaCuO Josephson junctions for fundamental


  We present various concepts and experimental procedures to produce
biepitaxial YBaCuO grain boundary Josephson junctions. The device properties
have an interesting phenomenology related in part to the possible influence of
"pai loops". The performance of our junctions and Superconducting Quantum
Interference Devices indicates significant improvement in the biepitaxial
technique. Further, we propose methods for fabricating circuits in which "0-"
and "pai-loops" are controllably located on the same chip.

</DOC>
<DOC>
<DOCNO> 120652 </DOCNO>
On the abundance of collapsed objects


  The redshift dependence of the abundance of collapsed objects places strong
constraints on cosmological models of structure formation. We apply a recently
proposed model describing the anisotropic collapse of inhomogeneous spatial
domains. Compared with the spherical top-hat model, this generic model leads
to significantly more collapsed objects at high redshifts: at redshift one and
on the scale of rich clusters a factor of 65. Furthermore, for a fixed
normalization of the initial fluctuation spectrum (\sigma_8=1), we predict four
times as much presently collapsed objects on the mass-scale of rich clusters
within the standard CDM cosmogony, compared to the spherical collapse.

</DOC>
<DOC>
<DOCNO> 71547 </DOCNO>
Gamma and Cosmic-Ray Tests of Special Relativity


  Lorentz symmetry violation (LSV) at Planck scale can be tested (see e.g.
physics/0003080) through ultra-high energy cosmic rays (UHECR). In a deformed
Lorentz symmetry (DLS) pattern where the effective LSV parameter varies like
the square of the momentum scale (quadratically deformed relativistic
kinematics, QDRK), a 10E-6 LSV at Planck scale would be enough to produce
observable effects on the properties of cosmic rays at the 10E20 eV scale:
absence of GZK cutoff, stability of unstable particles, lower interaction
rates, kinematical failure of any parton model and of standard formulae for
Lorentz contraction and time dilation... Its phenomenological implications are
compatible with existing data. If the effective LSV parameter is taken to vary
linearly with the momentum scale (linearly deformed relativistic kinematics,
LDRK), a LSV at Planck scale larger than 10E-7 eV seems to lead to
contradictions with data above TeV energies. Consequences are important for
high-energy gamma-ray experiments, as well as for high-energy cosmic rays and
gravitational waves.

</DOC>
<DOC>
<DOCNO> 40512 </DOCNO>
Recent Results from BES


  We report partial wave analysis results for $J/\psi \to \gamma K^+ K^-$ based
on $7.8 \times 10^6$ BESI $J/\psi$ events, and find $0^{++}$ to be dominant in
the $f_J(1710)$ mass region. Some very preliminary results are presented from
the $2.2 \times 10^7$ $J/\psi$ events newly collected at the upgraded
BES(BESII). Using the world largest $\psi(2S)$ data sample, BES measures
branching ratios of $\psi(2S)$ radiative and hadronic decays. The preliminary R
values measured by BESII in the 2-5 GeV energy region are also presented.

</DOC>
<DOC>
<DOCNO> 13396 </DOCNO>
Comment on "Extraction of work from a single thermal bath in the quantum


  Recently Allahverdyan and Nieuwenhuizen (cond-mat/0006404) argued that the
second law of thermodynamics may be violated in a quantum system as a
"consequence of quantum coherence in the presence of the slightly
off-equilibrium nature of the bath." By using a standard result about relative
entropy, we prove rigorously that the second law is never violated (and, in
particular, a perpetual motion of the second kind can never be realized) in
quantum systems no matter how strong ``quantum coherence'' is or no matter how
far one goes from equilibrium.

</DOC>
<DOC>
<DOCNO> 150428 </DOCNO>
Holography for degenerate boundaries


  We discuss the AdS/CFT correspondence for negative curvature Einstein
manifolds whose conformal boundary is degenerate in the sense that it is of
codimension greater than one. In such manifolds, hypersurfaces of constant
radius do not blow up uniformly as one increases the radius; examples include
products of hyperbolic spaces and the Bergman metric. We find that there is a
well-defined correspondence between the IR regulated bulk theory and conformal
field theory defined in a background whose degenerate geometry is regulated by
the same parameter. We are hence able to make sense of supergravity in
backgrounds such as $AdS_{3} \times H^{2}$.

</DOC>
<DOC>
<DOCNO> 84175 </DOCNO>
Selfdual Einstein metrics and conformal submersions


  Weyl derivatives, Weyl-Lie derivatives and conformal submersions are defined,
then used to generalize the Jones-Tod correspondence between selfdual
4-manifolds with symmetry and Einstein-Weyl 3-manifolds with an abelian
monopole. In this generalization, the conformal symmetry is replaced by a
particular kind of conformal submersion with one dimensional fibres. Special
cases are studied in which the conformal submersion is holomorphic, affine, or
projective. All scalar-flat Kahler metrics with such a holomorphic conformal
submersion, and all four dimensional hypercomplex structures with a compatible
Einstein metric, are obtained from solutions of the resulting ``affine monopole
equations''. The ``projective monopole equations'' encompass Hitchin's
twistorial construction of selfdual Einstein metrics from three dimensional
Einstein-Weyl spaces, and lead to an explicit formula for carrying out this
construction directly. Examples include new selfdual Einstein metrics depending
explicitly on an arbitrary holomorphic function of one variable or an arbitrary
axially symmetric harmonic function. The former generically have no continuous
symmetries.

</DOC>
<DOC>
<DOCNO> 85296 </DOCNO>
Gravitational Collapse in Constant Potential Bath


  We analyse here the gravitational collapse of directed null radiation in a
background with a constant potential such as one produced by a star system like
galaxy in which the collapsing object is immersed. Both naked singularities and
black holes are shown to be developing as the final outcome of the collapse. An
interesting feature that emerges is that a part of the naked singularity
spectrum in collapsing Vaidya region gets covered in the corresponding
dual-Vaidya region, which corresponds to the Vaidya directed null radiation
sitting in constant potential bath. The implications of such a result towards
the issue of stability of naked singularities are discussed.

</DOC>
<DOC>
<DOCNO> 9697 </DOCNO>
Simple description of metastable phase decay on wide spectrum of


  A new simple method for description of the nucleation process on the wide
class of heterogeneous centers is given. The nucleation occurs on the
heterogeneous centers with different heights of activation barriers. The
distribution of the total number of heterogeneous centers over the activation
barrier heights is supposed to be a smooth continuous function. This
description results in a simple analytical formulas for all main
characteristics of nucleation. Only a simple algebraic equation for the
paramters has to be solved to get concrete results.

</DOC>
<DOC>
<DOCNO> 117006 </DOCNO>
SNS Front End Diagnostics


  The Front End of the Spallation Neutron Source (SNS) extends from the Ion
Source (IS), through a 65 keV LEBT, a 402.5 MHz RFQ, a 2.5 MeV MEBT, ending at
the entrance to the DTL. The diagnostics suite in this space includes stripline
beam position and phase monitors (BPM), toroid beam current monitors (BCM), and
an emittance scanner. Provision is included for beam profile measurement,
either gas fluorescence, laser-based photodissociation, or a crawling wire.
Mechanical and electrical design and prototyping of BPM and BCM subsystems are
proceeding. Significant effort has been devoted to packaging the diagnostic
devices in minimal space. Close ties are maintained to the rest of the SNS
effort, to ensure long term compatibility of interfaces and in fact share some
design work and construction. The data acquisition, digital processing, and
control system interface needs for the BPM, BCM, and LEBT diagnostic are
similar, and we are committed to using an architecture common with the rest of
the SNS collaboration.

</DOC>
<DOC>
<DOCNO> 101316 </DOCNO>
An introduction to algebraic surgery


  Browder-Novikov-Sullivan-Wall surgery theory investigates the homotopy types
of manifolds, using a combination of algebra and topology. It is the aim of
these notes to provide an introduction to the more algebraic aspects of the
theory (such as the Wall surgery obstruction groups), without losing sight of
the geometric motivation.

</DOC>
<DOC>
<DOCNO> 14120 </DOCNO>
Corrections to scaling in systems with thermodynamic constraints


  Using thermodynamic arguments treatment it is shown that, independently on
whether Fisher renormalization changes the critical exponents near a phase
transition in a constrained system or not, new corrections to scaling with
correction exponents proportional to the specific heat index $\alpha$ appear.
Because of the smallness $\alpha$ for the Ising, the XY, and the Heisenberg
universality classes these corrections are dominant and can cause strong
crossover effects. It is proven that the appearance of Fisher corrections to
scaling is a quite general feature of the systems with constraints.

</DOC>
<DOC>
<DOCNO> 121140 </DOCNO>
Chandra estimate of the magnetic field strength near the cold front in


  We use the Chandra observation of the cold front in the intracluster gas of
A3667 to estimate the magnetic field strength near the front. The front is seen
in the Chandra data as a sharp discontinuity in the gas density which
delineates a large body of dense cool gas moving with the near-sonic velocity
through the less dense, hotter gas. Without a magnetic field, the front should
be quickly disturbed by the Kelvin-Helmholtz instability arising from
tangential motion of gas layers. However, Chandra image shows that the front is
stable within a +-30deg sector in the direction of the cloud motion, beyond
which it gradually disappears. We suggest that the Kelvin-Helmholtz instability
within the +-30deg sector is suppressed by surface tension of the magnetic
field whose field lines are parallel to the front. The required field strength
is B ~ 10 muG. Magnetic field near the front is expected to be stronger and
have very different structure compared to the bulk of the intergalactic medium,
because the field lines are stretched by the tangential gas motions. Such a
magnetic configuration, once formed, would effectively stop the plasma
diffusion and heat conduction across the front, and may inhibit gas mixing
during the subcluster merger. We note that even the increased magnetic field
near the front contributes only 10-20% to the total gas pressure, and therefore
magnetic pressure is unimportant for hydrostatic cluster mass estimates.

</DOC>
<DOC>
<DOCNO> 116244 </DOCNO>
Application of Conditioning to the Gaussian-with-Boundary Problem in the


  Roe and Woodroofe (RW) have suggested that certain conditional probabilities
be incorporated into the ``unified approach'' for constructing confidence
intervals, previously described by Feldman and Cousins (FC). RW illustrated
this conditioning technique using one of the two prototype problems in the FC
paper, that of Poisson processes with background. The main effect was on the
upper curve in the confidence belt. In this paper, we attempt to apply this
style of conditioning to the other prototype problem, that of Gaussian errors
with a bounded physical region. We find that the lower curve on the confidence
belt is also moved significantly, in an undesirable manner.

</DOC>
<DOC>
<DOCNO> 119271 </DOCNO>
A Color Analysis of the NICMOS Parallel Image Archive


  We present a photometric analysis of all high Galactic lattitude (|b| > 20d)
broad-band parallel images taken by the Near Infrared Camera and Multi-Object
Spectrometer (NICMOS) instrument during its initial lifetime in HST Cycle 7.
These images, taken through the F110W and F160W filters, reach a mean 3-sigma
limiting magnitude of approximately 22 in both bands, and cover a total area of
approximately 92 square arcminutes. The reddest of the 358 galaxies detected
have F110W-F160W colors and F160W magnitudes consistent with being a
combination of both dusty star-forming and evolved early-type galaxies at 1 < z
< 2. The surface density of these galaxies is comparable to that of the
population of Extremely Red Objects (EROs) discovered in ground-based surveys
(~ 100 deg-2), suggesting that EROs also represent a combination of both galaxy
types in this redshift range. Roughly 10% of the detected galaxies appear to be
blue compact dwarf galaxies at z < 1, a result consistent with studies of the
HST Medium Deep Survey Fields. The surface density of these objects down to
magnitude of 22 in F160W is ~ 300 deg-2. None of the 681 point sources detected
have F110W-F160W colors matching those expected for QSOs whose continua have
been significantly reddened by internal dust. Our data limit the surface
density of such QSOs to be < 50 deg-2 down the mean limiting magnitudes of the
sample images. Since the surface density of QSOs detected on the basis of
ultraviolet excess in optical surveys to comparable depth is ~ 100 deg-2, this
argues against the suggestion that dust-reddened QSOs comprise the undetected
majority of the QSO population. The F110W-F160W color can also be used to
identify unreddened QSOs at z > 8, but we find no such candidates. This is
consistent with the evidence that QSO space density declines sharply at z > 5.

</DOC>
<DOC>
<DOCNO> 169653 </DOCNO>
Bohmian mechanics contradicts quantum mechanics


  It is shown that, for a harmonic oscillator in the ground state, Bohmian
mechanics and quantum mechanics predict values of opposite sign for certain
time correlations.
  The discrepancy can be explained by the fact that Bohmian mechanics has no
natural way to accomodate the Heisenberg picture, since the local expectation
values that define the beables of the theory depend on the Heisenberg time
being used to define the operators.
  Relations to measurement are discussed, too, and shown to leave no loophole
for claiming that Bohmian mechanics reproduces all predictions of quantum
mechanics exactly.

</DOC>
<DOC>
<DOCNO> 169738 </DOCNO>
Symmetric Classical Mechanics


  We investigate the possibility that the semiclassical limit of quantum
mechanics might be correctly described by a classical dynamical theory, other
than standard classical mechanics. Using a set of classicality criteria
proposed in a related paper, we show that the time evolution of a set of
quantum initial data satisfying these criteria is fully consistent with the
predictions of a new theory of classical dynamics. The dynamical structure of
the new theory is given by the Moyal bracket. This is a Lie bracket that was
first derived as the dynamical structure of the Moyal-Weyl-Wigner formulation
of quantum mechanics. We present a new derivation of the Moyal bracket, this
time in the context of the semiclassical limit of quantum mechanics and thus
prove that both classical and quantum dynamics can be formulated in terms of
the same canonical structure.

</DOC>
<DOC>
<DOCNO> 9480 </DOCNO>
Structure of Growing Networks: Exact Solution of the Barabasi--Albert's


  We generalize the Barab\'{a}si--Albert's model of growing networks accounting
for initial properties of sites and find exactly the distribution of
connectivities of the network $P(q)$ and the averaged connectivity
$\bar{q}(s,t)$ of a site $s$ in the instant $t$ (one site is added per unit of
time). At long times $P(q) \sim q^{-\gamma}$ at $q \to \infty$ and
$\bar{q}(s,t) \sim (s/t)^{-\beta}$ at $s/t \to 0$, where the exponent $\gamma$
varies from 2 to $\infty$ depending on the initial attractiveness of sites. We
show that the relation $\beta(\gamma-1)=1$ between the exponents is universal.

</DOC>
<DOC>
<DOCNO> 68465 </DOCNO>
Exact and approximate dynamics of the quantum mechanical O(N) model


  We study a quantum dynamical system of N, O(N) symmetric, nonlinear
oscillators as a toy model to investigate the systematics of a 1/N expansion.
The closed time path (CTP) formalism melded with an expansion in 1/N is used to
derive time evolution equations valid to order 1/N (next-to-leading order). The
effective potential is also obtained to this order and its properties
areelucidated. In order to compare theoretical predictions against numerical
solutions of the time-dependent Schrodinger equation, we consider two initial
conditions consistent with O(N) symmetry, one of them a quantum roll, the other
a wave packet initially to one side of the potential minimum, whose center has
all coordinates equal. For the case of the quantum roll we map out the domain
of validity of the large-N expansion. We discuss unitarity violation in the 1/N
expansion; a well-known problem faced by moment truncation techniques. The 1/N
results, both static and dynamic, are also compared to those given by the
Hartree variational ansatz at given values of N. We conclude that late-time
behavior, where nonlinear effects are significant, is not well-described by
either approximation.

</DOC>
<DOC>
<DOCNO> 12320 </DOCNO>
Mediation of Long Range Charge Transfer by Kondo Bound States


  We present a theory of non-equilibrium long range charge transfer between
donor and acceptor centers in a model polymer mediated by magnetic exciton
(Kondo) bound states. Our model produces electron tunneling lengths easily
exceeding 10$\AA$, as observed recently in DNA and organic charge transfer
systems. This long ranged tunneling is effective for weak to intermediate
donor-bridge coupling, and is enhanced both by weak to intermediate strength
Coulomb hole-electron attraction (through the orthogonality catastrophe) and by
coupling to local vibrational modes.

</DOC>
<DOC>
<DOCNO> 40183 </DOCNO>
The Q^2-dependence of the Generalised Gerasimov-Drell-Hearn Integral for


  The dependence on Q^2 (the negative square of the 4-momentum of the exchanged
virtual photon) of the generalised Gerasimov-Drell-Hearn integral for the
proton has been measured in the range 1.2 GeV^2 < Q^2 < 12 GeV^2 by scattering
longitudinally polarised positrons on a longitudinally polarised hydrogen gas
target. The contributions of the nucleon-resonance and deep-inelastic regions
to this integral have been evaluated separately. The latter has been found to
dominate for Q^2 > 3 GeV^2, while both contributions are important at low Q^2.
The total integral shows no significant deviation from a 1/Q^2 behaviour in the
measured Q^2 range, and thus no sign of large effects due to either
nucleon-resonance excitations or non-leading twist.

</DOC>
<DOC>
<DOCNO> 122886 </DOCNO>
Identification of the donor in GRS 1915+105


  We report on the results of medium-resolution spectroscopy of GRS 1915+105 in
the H and K band using the 8m VLT at ESO. We clearly identify absorption
bandheads from CO12 and CO13. Together with other features this results in a
classification of the donor as a K-M III star.

</DOC>
<DOC>
<DOCNO> 85383 </DOCNO>
Kaluza-Klein Vortices


  We study static vortex type solutions of pure gravity for $D \geq 4+1 $.
Non-singular vortex solutions can be obtained by considering periodic
Kaluza-Klein monopoles. We also show that away from the center of the vortices
the space is described by the gravitational instantons derived from minimal
surfaces.

</DOC>
<DOC>
<DOCNO> 12681 </DOCNO>
Quantum Numbers of the V3+ Ion in V2o3


  It is argued that the V3+ ion in V2O3 should be considered as described by
quantum numbers S=1 and L=3. It results from Hund's rules and means that the
two d electrons form the highly- correlated electron system with the importance
of the intra-atomic spin-orbit coupling. Keywords: highly-correlated electron
system, crystal-field, spin- orbit coupling, orbital moment, V3+ ion. PACS:
71.70.E, 75.10.D, 75.30.Gw

</DOC>
<DOC>
<DOCNO> 120130 </DOCNO>
X-ray colour maps of the cores of galaxy clusters


  We present an analysis of X-ray colour maps of the cores of clusters of
galaxies, formed from the ratios of counts in different X-ray bands. Our
technique groups pixels lying between contours in an adaptively-smoothed image
of a cluster. We select the contour levels to minimize the uncertainties in the
colour ratios, whilst preserving the structure of the object. We investigate
the spatial distributions of cooling gas and absorbing material for a sample of
33 X-ray bright clusters, many containing strong cooling flows, in archival
ROSAT PSPC data. We present colour maps of a sample of the clusters, in
addition to adaptively-smoothed images in different bands. Most of the cooling
flow clusters display little substructure, unlike several of the
non-cooling-flow clusters.
  We fitted an isothermal plasma model with galactic absorption and constant
metallicity to the mid-over-high energy colours in our clusters. Those clusters
with known strong cooling flows have inner contours which fit a significantly
lower temperature than the outer contours. Clusters in the sample without
strong cooling flows show no significant temperature variation. We also had to
increase the levels of absorbing material to fit the low-over-high colours at
the cluster centres. Our results provide more evidence that cooling flows
accumulate absorbing material. No evidence for increased absorption was found
for the non-cooling-flow clusters. [abridged]

</DOC>
<DOC>
<DOCNO> 71458 </DOCNO>
Common Features of Particle Multiplicities in Heavy Ion Collisions


  Results of a systematic study of fully integrated particle multiplicities in
central Au-Au and Pb-Pb collisions at beam momenta 1.7 A GeV, 11.6 A GeV
(Au-Au) and 158 A GeV (Pb-Pb) using a statistical-thermal model are presented.
The close similarity of the colliding systems makes it possible to study heavy
ion collisions under definite initial conditions over a range of centre-of-mass
energies covering more than one order of magnitude. We conclude that a thermal
model description of particle multiplicities, with additional strangeness
suppression, is possible for each energy. The degree of chemical equilibrium of
strange particles and the relative production of strange quarks with respect to
u and d quarks are higher than in e+e-, pp and pp(bar) collisions at comparable
and even at lower energies. The average energy per hadron in the comoving frame
is always close to 1 GeV per hadron despite the fact that the energy varies
more than 10-fold.

</DOC>
<DOC>
<DOCNO> 178473 </DOCNO>
Moments of inertia for multi-quasiparticle configurations


  Tilted-axis cranking calculations have been performed for multi-quasiparticle
states in well deformed A$\approx$180 nuclei. In the limit of zero pairing, not
only are the calculated moments of inertia substantially smaller than for rigid
rotation, but also they are close to the experimental values. The moments of
inertia are found to be insensitive to dynamic pair correlations.

</DOC>
<DOC>
<DOCNO> 150685 </DOCNO>
Stable non-BPS D-branes of type I


  We review the boundary state description of the non-BPS D-branes in the type
I string theory and show that the only stable configurations are the D-particle
and the D-instanton. We also compute the gauge and gravitational interactions
of the non-BPS D-particles and compare them with the interactions of the dual
non-BPS particles of the heterotic string finding complete agreement. In this
way we provide further dynamical evidence of the heterotic/type I duality.

</DOC>
<DOC>
<DOCNO> 83132 </DOCNO>
A Splitting Set Theorem for Epistemic Specifications


  Over the past decade a considerable amount of research has been done to
expand logic programming languages to handle incomplete information. One such
language is the language of epistemic specifications. As is usual with logic
programming languages, the problem of answering queries is intractable in the
general case. For extended disjunctive logic programs, an idea that has proven
useful in simplifying the investigation of answer sets is the use of splitting
sets. In this paper we will present an extended definition of splitting sets
that will be applicable to epistemic specifications. Furthermore, an extension
of the splitting set theorem will be presented. Also, a characterization of
stratified epistemic specifications will be given in terms of splitting sets.
This characterization leads us to an algorithmic method of computing world
views of a subclass of epistemic logic programs.

</DOC>
<DOC>
<DOCNO> 71586 </DOCNO>
Effect of reheating on electroweak baryogenesis


  The latent heat released during the expansion of bubbles in the electroweak
phase transition reheats the plasma and causes the bubble growth to slow down.
This decrease of the bubble wall velocity affects the result of electroweak
baryogenesis. Since the efficiency of baryogenesis peaks for a wall velocity
$\sim 10^{-2}$, the resulting baryon asymmetry can either be enhanced or
suppressed, depending on the initial value of the wall velocity. We calculate
the evolution of the phase transition taking into account the release of latent
heat. We find that, although in the SM the baryon production is enhanced by
this effect, in the MSSM it causes a suppression to the final baryon asymmetry.

</DOC>
<DOC>
<DOCNO> 71286 </DOCNO>
Aspects of semi-classical transport theory for QCD


  We discuss some aspects of a recently proposed semi-classical transport
theory for QCD plasmas based on coloured point particles. This includes the
derivation of effective transport equations for mean fields and fluctuations
which relies on the Gibbs ensemble average. Correlators of fluctuations are
interpreted as collision integrals for the effective Boltzmann equation. The
approach yields a recipe to integrate-out fluctuations. Systematic
approximations (first moment, second moment, polarisation approximation) based
on a small plasma parameter are discussed as well. Finally, the application to
a hot non-Abelian plasma close to thermal equilibrium is considered and the
consistency with the fluctuation-dissipation theorem established.

</DOC>
<DOC>
<DOCNO> 10274 </DOCNO>
Non-analyticity of the Callan-Symanzik beta-function of two-dimensional


  We discuss the analytic properties of the Callan-Symanzik beta-function
beta(g) associated with the zero-momentum four-point coupling g in the
two-dimensional phi^4 model with O(N) symmetry. Using renormalization-group
arguments, we derive the asymptotic behavior of beta(g) at the fixed point g^*.
We argue that beta'(g) = beta'(g^*) + O(|g-g^*|^{1/7}) for N=1 and beta'(g) =
beta'(g^*) + O(1/\log |g-g^*|) for N > 2. Our claim is supported by an explicit
calculation in the Ising lattice model and by a 1/N calculation for the
two-dimensional phi^4 theory. We discuss how these nonanalytic corrections may
give rise to a slow convergence of the perturbative expansion in powers of g.

</DOC>
<DOC>
<DOCNO> 71731 </DOCNO>
Signatures of Precocious Unification in Orbiting Detectors


  It has been conjectured that the string and unification scales may be
substantially lower than previously believed, perhaps a few TeV. In scenarios
of this type, orbiting detectors such OWL or AIRWATCH can observe spectacular
phenomena at trans-GZK energies. We explore measurable signatures of the
hypothesis that trans-GZK air showeres (``anomalous showers'') are originated
by strongly interacting neutrinos. The results of a MC simulation of such air
showers is described. A distinction between proton induced and ``anomalous''
showers becomes possible once a substantial sample of trans-GZK showers will be
available.

</DOC>
<DOC>
<DOCNO> 67822 </DOCNO>
Mass Shift of Axion in Magnetic Field


  A mass-shift of the axion propagating in an external constant homogenious
magnetic field is calculated. The contributions via an electron loop and a
virtual photon are examined. It is shown that the virtual photon contribution
dominates substantially over the electron-loop one. Under the conditions of the
early Universe the electron-loop contribution to the massless axion mass-shift
is equal to zero while the virtual photon contribution is finite and can be of
order of the recent restrictions on the axion mass.

</DOC>
<DOC>
<DOCNO> 150835 </DOCNO>
Noncommutative Gauge Theory, Divergences and Closed Strings


  We study the renormalization of non-commutative gauge theories with matter.
 As in the scalar field theory cases, there are logarithmic infrared
divergences resulting from integrating out high momentum modes. In order to
reproduce the correct infrared behaviour, the Wilsonian effective action has to
include certain ''closed string`` modes with prescribed couplings.
  In the case of quiver gauge theories, realized in string theory on orbifolds,
we identify the required modes with a set of twisted sector fields. These
closed string modes have exactly the prescribed couplings to correct the
Wilsonian effective action. This provides a concrete origin for the appearance
of closed string modes in noncommutative field theories.

</DOC>
<DOC>
<DOCNO> 119693 </DOCNO>
X-ray observations of the starburst galaxy NGC 253:II. Extended emission


  Spatial and spectral analysis of deep ROSAT HRI and PSPC observations of the
near edge-on starburst galaxy NGC 253 reveal diffuse soft X-ray emission, which
contributes 80% to its total X-ray luminosity (L$_{\rm X} = 5 10^{39}$ \ergsec,
corrected for foreground absorption). The nuclear area, disk, and halo
contribution to the luminosity is about equal. The starburst nucleus itself is
highly absorbed and not visible in the ROSAT band.
  We describe in detail spectra and morphology of the emission from the nuclear
area, disk and halo and compare our results to observations at other
wavelengths and from other galaxies. (abridged)

</DOC>
<DOC>
<DOCNO> 116494 </DOCNO>
Revitalization of an undergraduate physics program


  This article describes the successful revitalization of an undergraduate
physics program. The areas of curriculum development, undergraduate research
experiences and advising and retention, to name a few, are emphasized in this
interconnecting and systematic approach whereby each and every effort combines
to get results. The program can be used by other physics departments wishing to
improve and expand undergraduate education in physics.

</DOC>
<DOC>
<DOCNO> 99947 </DOCNO>
Explicit Formulae for Cocycles of Holomorphic Vector Fields with values


  We give explicit formulae for the generators of H^2(Hol(\Sigma_r,{\cal
F}_{\lambda}(\Sigma_r)) in terms of affine and projective connections. This is
done using the cocycles of V. Ovsienko and C. Roger for the case of the circle
and globalizing them to an open Riemann surface \Sigma_r.

</DOC>
<DOC>
<DOCNO> 11744 </DOCNO>
Quantum Films Adsorbed on Graphite: Third and Fourth Helium Layers


  Using a path-integral Monte Carlo method for simulating superfluid quantum
films, we investigate helium layers adsorbed on a substrate consisting of
graphite plus two solid helium layers. Our results for the promotion densities
and the dependence of the superfluid density on coverage are in agreement with
experiment. We can also explain certain features of the measured heat capacity
as a function of temperature and coverage.

</DOC>
<DOC>
<DOCNO> 118739 </DOCNO>
Photometric Redshifts based on standard SED fitting procedures


  In this paper we study the accuracy of photometric redshifts computed through
a standard SED fitting procedure, where SEDs are obtained from broad-band
photometry. We present our public code hyperz, which is presently available on
the web. We introduce the method and we discuss the expected influence of the
different observational conditions and theoretical assumptions. In particular,
the set of templates used in the minimization procedure (age, metallicity,
reddening, absorption in the Lyman forest, ...) is studied in detail, through
both real and simulated data. The expected accuracy of photometric redshifts,
as well as the fraction of catastrophic identifications and wrong detections,
is given as a function of the redshift range, the set of filters considered,
and the photometric accuracy. Special attention is paid to the results expected
from real data.

</DOC>
<DOC>
<DOCNO> 169689 </DOCNO>
Methodology for quantum logic gate constructions


  We present a general method to construct fault-tolerant quantum logic gates
with a simple primitive, which is an analog of quantum teleportation. The
technique extends previous results based on traditional quantum teleportation
(Gottesman and Chuang, Nature {\bf 402}, 390, 1999) and leads to
straightforward and systematic construction of many fault-tolerant encoded
operations, including the $\pi/8$ and Toffoli gates. The technique can also be
applied to the construction of remote quantum operations that cannot be
directly performed.

</DOC>
<DOC>
<DOCNO> 13921 </DOCNO>
Local Quasiparticle States near a Unitary Impurity with Induced Magnetic


  The local quasiparticle density of states around a unitary impurity with a
Kondo-like magnetic moment induced at its nearest neighbors in a d-wave
superconductor is studied within the slave-boson mean-field approach. The
Hamiltonian is exactly diagonalized and the results are obtained
self-consistently. We show that the interference between the strong impurity
potential scattering and the Kondo effect leads to novel quasiparticle spectra
around the impurity, which are strikingly different from the case of a single
unitary or magnetic impurity. The recent STM image of the local differential
tunneling conductance around a Zn impurity in a high-T_c cuprate can be
essentially explained if the blocking effect of BiO surface layer between the
tip and probed CuO_2 plane [Zhu et al., Phys. Rev. B 62, 6207 (2000)] is taken
into account.

</DOC>
<DOC>
<DOCNO> 101702 </DOCNO>
Torsions and Curvatures on Jet Fibre Bundle J^1(T,M)


  The paper introduces the notion of \Gamma-linear connection \nabla on the
1-jet fibre bundle J^1(T,M), and presents its local components. We also
describe the local Ricci and Bianchi identities of $\nabla$.

</DOC>
<DOC>
<DOCNO> 170451 </DOCNO>
A Complexity Measure for Continuous Time Quantum Algorithms


  We consider unitary dynamical evolutions on n qubits caused by time dependent
pair-interaction Hamiltonians and show that the running time of a parallelized
two-qubit gate network simulating the evolution is given by the time integral
over the chromatic index of the interaction graph. This defines a complexity
measure of continuous and discrete quantum algorithms which are in exact
one-to-one correspondence. Furthermore we prove a lower bound on the growth of
large-scale entanglement depending on the chromatic index.

</DOC>
<DOC>
<DOCNO> 13048 </DOCNO>
Leaky interface phonons in AlGaAs/GaAs structures


  A dispersion equation for the interface waves has been derived for the
interface of two cubic crystals in the plane perpendicular to [001]. A
reasonable hypothesis has been made about the total number of the acoustic
modes. Due to this hypothesis the number is 64, but not all of the modes have
physical meaning of the interface waves. The rules have been worked out to
select physical branches among all 64 roots of dispersion equation. The
physical meaning of leaky interface waves is discussed. The calculations have
been made for the interface Al$_{0.3}$Ga$_{0.7}$As/GaAs. In this case all
physical interface modes have been shown to be leaky. The velocities of the
interface waves are calculated as a function of an angle in the plane of
interface. The results support a recent interpretation of a new type
oscillations of magnetoresistance as a resonant scattering of two-dimensional
electron gas by the leaky interface phonons.

</DOC>
<DOC>
<DOCNO> 99562 </DOCNO>
On Symplectically Harmonic Forms on Six-dimensional Nilmanifolds


  In the present paper we study the variation of the dimensions $h_k$ of spaces
of symplectically harmonic cohomology classes (in the sense of Brylinski) on
closed symplectic manifolds. We give a description of such variation for all
6-dimensional nilmanifolds equipped with symplectic forms. In particular, it
turns out that certain 6-dimensional nilmanifolds possess families of
homogeneous symplectic forms $\omega_t$ for which numbers $h_k(M,\omega_t)$
vary with respect to t. This gives an affirmative answer to a question raised
by Boris Khesin and Dusa McDuff. Our result is in contrast with the case of
4-dimensional nilmanifolds which do not admit such variations by a remark of
Dong Yan.

</DOC>
<DOC>
<DOCNO> 151546 </DOCNO>
Self dual models and mass generation in planar field theory


  We analyse in three space-time dimensions, the connection between abelian
self dual vector doublets and their counterparts containing both an explicit
mass and a topological mass. Their correspondence is established in the
lagrangian formalism using an operator approach as well as a path integral
approach. A canonical hamiltonian analysis is presented, which also shows the
equivalence with the lagrangian formalism. The implications of our results for
bosonisation in three dimensions are discussed.

</DOC>
<DOC>
<DOCNO> 117799 </DOCNO>
Electromagnetic Energy for a Charged Kerr Black Hole in a Uniform


  With the Komar mass formula we calculate the electromagnetic energy for a
charged Kerr black hole in a uniform magnetic field. We find that the total
electromagnetic energy takes the minimum when the Kerr black hole possesses a
non-zero net charge $Q = 2\xi B_0 J_H$ where $B_0$ is the strength of the
magnetic field, $J_H$ is the angular momentum of the black hole, $\xi$ is a
dimensionless parameter determined by the spin of the black hole.

</DOC>
<DOC>
<DOCNO> 68766 </DOCNO>
Chiral aspects of baryon structure in the quark model


  The implications of chiral symmetry for the quark model are discussed. In
particular its connection with the meson-baryon approach is outlined. It is
stressed that in the closure approximation, where the intermediate baryon
states are used instead of the original quark basis, it is imperative to take
into account the whole infinite tower of the radially excited states in order
that the crucially important effects related to the short-range part of the
meson-exchange interaction be preserved. It is shown that the chiral
constituent quark model is able to explain the nucleon axial vector coupling
constant and automatically incorporates all the necessary loop corrections.

</DOC>
<DOC>
<DOCNO> 170736 </DOCNO>
An Attack to Quantum Cryptography from Space


  The promise of secure cryptographic quantum key distribution schemes is based
on the use of quantum effects in the spin space. We point out that in fact in
many current quantum cryptography protocols the space part of the wave function
is neglected. However exactly the space part of the wave function describes the
behaviour of particles in ordinary real three-dimensional space. As a result
such schemes can be secure against eavesdropping attacks in the abstract spin
space but could be insecure in the real three-dimensional space. We discuss an
approach to the security of quantum key distribution in space by using Bell's
inequality and a special preparation of the space part of the wave function.

</DOC>
<DOC>
<DOCNO> 170197 </DOCNO>
Interference and the lossless lossy beam splitter


  By directing the input light into a particular mode it is possible to obtain
as output all of the input light for a beam splitter that is 50% absorbing.
This effect is also responsible for nonlinear quantum interference when two
photons are incident on the beam splitter.

</DOC>
<DOC>
<DOCNO> 101847 </DOCNO>
Quantum differential operators on K[x]


  Following the definition of quantum differential operators given by Lunts and
Rosenberg in (Sel. math., New ser. 3 (1997) 335--359), we show that the ring of
quantum differential operators on the affine line is the ring generated by x
and \del, the familiar differential operators on the line, along with two
additional operators which we call \del^\beta^1 and \del^\beta^-1. We describe
this ring both as a subring of the ring of graded endomorphisms and as a ring
given by generators and relations. From this starting point, we are able to
describe the ring of quantum differential operators on affine n-space and to
construct the ring of global quantum differential operators on the projective
line.

</DOC>
<DOC>
<DOCNO> 84656 </DOCNO>
Detection of gravitational waves from inspiraling compact binaries using


  The set up of matched filters for the detection of gravitational waves from
in-spiraling compact binaries is usually carried out using the restricted
post-Newtonian approximation: the filter phase is modelled including
post-Newtonian corrections, whereas the amplitude is retained at the Newtonian
order. Here we investigate the effects of the introduction of post-Newtonian
corrections also to the amplitude and we discuss some of the implications for
signal detection and parameter estimation.

</DOC>
<DOC>
<DOCNO> 40172 </DOCNO>
Measurement of the W-Pair Production Cross Section and W-Decay Branching


  The data collected by the L3 experiment at LEP at a centre-of-mass energy of
188.6 GeV are used to measure the W-pair production cross section and the
W-boson decay branching fractions. These data correspond to an integrated
luminosity of 176.8pb^-1. The total cross section for W-pair production,
combining all final states, is measured to be sigma_WW = 16.24 +/- 0.37(stat.)
+/- 0.22(syst.) pb. Including our data collected at lower centre-of-mass
energies, the hadronic branching fraction of the W-boson is determined to be
B(W ->qq) = [68.20 +/- 0.68 (stat.) +/- 0.33 (syst.) ] %. The results agree
with the Standard Model predictions.

</DOC>
<DOC>
<DOCNO> 84197 </DOCNO>
Symmetries and conservation laws in histories-based theories


  Symmetries are defined in histories-based theories paying special attention
to the class of history theories admitting quasitemporal structure (a
generalization of the concept of `temporal sequences' of `events' using partial
semigroups) and logic structure for `single-time histories'. Symmetries are
classified into orthochronous (those preserving the `temporal order' of
`events') and nonorthochronous. A straightforward criterion for physical
equivalence of histories is formulated in terms of orthochronous symmetries;
this criterion covers various notions of physical equivalence of histories
considered by Gell-Mann and Hartle as special cases. In familiar situations, a
reciprocal relationship between traditional symmetries (Wigner symmetries in
quantum mechanics and Borel-measurable transformations of phase space in
classical mechanics) and symmetries defined in this work is established. In a
restricted class of theories, a definition of conservation law is given in the
history language which agrees with the standard ones in familiar situations; in
a smaller subclass of theories, a Noether type theorem (implying a connection
between continuous symmetries of dynamics and conservation laws) is proved. The
formalism evolved is applied to histories (of particles, fields or more general
objects) in general curved spacetimes. Sharpening the definition of symmetry so
as to include a continuity requirement, it is shown that a symmetry in our
formalism implies a conformal isometry of the spacetime metric.

</DOC>
<DOC>
<DOCNO> 68657 </DOCNO>
Extending the Velocity-dependent One-scale String Evolution Model


  We provide a general overview of the velocity-dependent one-scale model for
cosmic string evolution and discuss two further extensions to it. We introduce
and justify a new ansatz for the momentum parameter $k$, and also incorporate
the effect of radiation backreaction. We thus discuss the evolution of the
basic large-scale features of cosmic string networks in all relevant
cosmological scenarios, concentrating in particular on the `scaling' solutions
relevant for each case. In a companion paper, we show, by comparing with
numerical simulations, that this model provides an accurate description of the
large-scale features of cosmic string networks.

</DOC>
<DOC>
<DOCNO> 118590 </DOCNO>
New evidence for the complex struscture of the RGB of Omega Cen


  We report on the complex structure of the red giant branch (RGB) of omega
Cen, based on a new wide field and wide color baseline B and I photometry. Our
color magnitude diagram (CMD) shows the presence of multiple populations along
this branch, in particular we discovered an anomalous branch (RGB-a), which
appears to be well separated from the bulk of the RGB stars. On the basis of
our CMD and from the previous literature we conclude that (1) these stars,
clearly identified as a separate population in our CMD, represent the extreme
metal rich extension ([Ca/H]>-0.3) of the stellar content of omega Cen, and
show anomalous abundances of s-process elements (as Ba and Zr) as well; (2)
they are physical members of the omega Cen system; (3) they comprise ~ 5% of
the stars of the whole system; (4) this component and the metal-intermediate
one (-0.4>[Ca/H]>-1) have been found to share the same spatial distribution,
both of them differing significantly from the most metal poor one ([Ca/H]<-1).
This last evidence supports the hypothesis that metal rich components could
belong to an independent (proto?) stellar system captured in the past by omega
Cen.

</DOC>
<DOC>
<DOCNO> 151400 </DOCNO>
Brane-World Cosmology in Higher Derivative Gravity or Warped


  The general model of higher derivative (HD) gravity is considered. The search
of brane-world cosmology in such theory is presented when bulk is d5 AdS and
boundary is spherical, hyperbolic or flat (single) brane. It is found the wide
range of theory parameters where such cosmology may be realized. Special
attention is paid to the version of HD theory representing SG dual of ${\cal
N}=2$ $Sp(N)$ SCFT (in next-to-leading order of large $N$ expansion). In
particular, it is shown that inflationary brane Universe does not occur for SG
dual while hyperbolic brane occurs (which was not possible in leading order).
  The quantum effects of CFT living on the brane (via the corresponding
conformal anomaly induced effective action) may qualitatively change the
results of classical analysis. There appears inflationary (or hyperbolic) brane
Universe induced by only quantum effects. In AdS/CFT correspondence
(next-to-leading order) the addition of such CFT effective action (in some
energy region) is naturally explained in terms of holographic renormalization
group. It results in the possibility of quantum creation of inflationary brane
Universe (with small rate) even for SG dual.

</DOC>
<DOC>
<DOCNO> 118307 </DOCNO>
The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables


  We combine new CCD UBV photometry and spectroscopy with that from the
literature to investigate 19 Magellanic Cloud OB associations that contain
Wolf-Rayet (WR) and other types of evolved massive stars. Our spectroscopy
reveals a wealth of newly identified interesting objects, including early
O-type supergiants, a high mass double-lined binary in the SMC, and, in the
LMC, a newly confirmed LBV (R 85), a newly discovered WR star (Sk-69 194), and
a newly found luminous B[e] star (LH85-10). We use the data to evaluate the
extent that each association is coeval, and for the ones with little age
spread, determine the turn-off masses of the unevolved stars, as a means of
finding the progenitor masses of LBVs and WRs. Our data is also used to find
the (minimum) bolometric corrections that apply to these evolved objects. We
find that WRs in the SMC come from only the highest mass stars (>70Mo), while
in the LMC the WNEs come from a wide range of masses---possibly all stars with
masses >30Mo pass though a WNE stage at LMC metallicities. In both the SMC and
LMC the WCs appear to come from the same mass range as do the WNs, a finding
that has important implications for interpreting the WC/WN ratio among Local
Group galaxies. LBVs appear to come from the very highest mass stars. The
Ofpe/WN9 stars, sometimes implicated in the "LBV phenonomon" come from very
modest mass stars, 25-35Mo, suggesting a different origin for their
variability. The BCs of WRs are considerably more negative than those of O-type
stars, with BC(WNE)=-6.0 mag and BC(WC4)=-5.5mag; more modest values are found
for the Ofpe/WN9 stars (-2 to -4 mag). These findings are consistent with
recent analysis done with Hillier's "standard model".

</DOC>
<DOC>
<DOCNO> 119215 </DOCNO>
Infrared observations of gravitational lensing in Abell 2219 with CIRSI


  We present the first detection of a gravitational depletion signal at
near-infrared wavelengths, based on deep panoramic images of the cluster Abell
2219 (z=0.22) taken with the Cambridge Infrared Survey Instrument (CIRSI) at
the prime focus of the 4.2m William Herschel Telescope. Infrared studies of
gravitational depletion offer a number of advantages over similar techniques
applied at optical wavelengths, and can provide reliable total masses for
intermediate redshift clusters. Using the maximum likelihood technique
developed by Schneider, King & Erben (1999), we detect the gravitational
depletion at the 3 sigma confidence level. By modeling the mass distribution as
a singular isothermal sphere and ignoring uncertainty in the unlensed number
counts, we find an Einstein radius of 13.7 +3.9/-4.2 arcsec (66% confidence
limit). This corresponds to a projected velocity dispersion of approximately
800 km/s, in agreement with constraints from strongly-lensed features. For a
Navarro, Frenk and White mass model, the radial dependence observed indicates a
best-fitting halo scale length of 125/h kpc}. We investigate the uncertainties
arising from the observed fluctuations in the unlensed number counts, and show
that clustering is the dominant source of error. We extend the maximum
likelihood method to include the effect of incompleteness, and discuss the
prospects of further systematic studies of lensing in the near-infrared band.

</DOC>
<DOC>
<DOCNO> 84518 </DOCNO>
Generalized slow-roll inflation


  The slow-roll approximation to inflation is ultimately justified by the
presence of inflationary attractors for the orbits of the solutions of the
dynamical equations in phase space. There are many indications that the
inflaton field couples nonminimally to the spacetime curvature: the existence
of attractor points for inflation with nonminimal coupling is demonstrated,
subject to a condition on the inflaton potential and the value of the coupling
constant.

</DOC>
<DOC>
<DOCNO> 70231 </DOCNO>
Probing the Structure of Nucleons in the Resonance Region with CLAS at


  The physics of electromagnetic excitation of nucleon resonances and of their
relevance in nucleon structure studies are discussed. Preliminary data from the
CLAS detector on the N-Delta(1232) transition multipoles, the helicity
amplitudes of the N*(1535), and the search for so-called "missing resonances"
at Jefferson Lab are presented.

</DOC>
<DOC>
<DOCNO> 117382 </DOCNO>
Electron densities, temperatures and ionization rates in two


  The spectrum of beta CMa (Mirzam) between 1000 and 1200 A was recorded at a
wavelength resolving power ~ 60 000 by the Interstellar Medium Absorption
Profile Spectrograph (IMAPS) during its orbital flight on the ORFEUS-SPAS II
mission in 1996. New information about interstellar absorption lines of CII,
CII*, NI and OI from this spectrum are combined with the HST results reported
by Dupin & Gry (1998) to arrive at new conclusions about the physical
properties of the absorbing gas in front of beta CMa. For two prominent
velocity components centered at heliocentric velocities of +20.0 and +30.5
km/s, designated by Dupin & Gry as Components C and D respectively, we use
determinations of N(CII*)/N(CII) and N(MgI)/N(MgII) to solve for temperatures
and electron densities. From our knowledge that oxygen and nitrogen have their
ionizations coupled to that of hydrogen through charge exchange reactions, we
can derive the hydrogen ionizations by comparing these elements to sulfur,
which is likely not to be depleted onto dust grains. For Component C with an
approximate column density of neutral and ionized hydrogen N(Htotal)=6 10^{18}
cm^-2, we find that the neutral fraction n(HI)/n(Htotal)=0.25, 400<T<6500 K,
and 0.08<n(e)<0.6 cm^-3, while for Component D with N(Htotal)=1.2 10^{19}cm^-2,
we arrive at n(HI)/n(Htotal)=0.035, 8000<T<14000 K, and 0.09<n(e)<0.2cm^-3. The
relatively large ionization fractions of H can arise if the clouds are about
130 pc away from us, so that they are exposed to the strong, ionizing radiation
fields from epsilon and beta CMa. The presence of SiIII indicates the existence
of additional gas with even higher levels of ionization.

</DOC>
<DOC>
<DOCNO> 179044 </DOCNO>
A Relativistic Symmetry in Nuclei: Its origins and consequences


  We review the status of quasi-degenerate doublets in nuclei, called
pseudospin doublets, which were discovered about thirty years ago and the
origins of which have remained a mystery, until recently. We show that
pseudospin doublets originate from an SU(2) symmetry of the Dirac Hamiltonian
which occurs when the sum of the scalar and vector potentials is a constant.
Furthermore, we survey the evidence that pseudospin symmetry is approximately
conserved in nuclear spectra and eigenfunctions and in nucleon-nucleus
scattering for a Dirac Hamiltonian with realistic nuclear scalar and vector
potentials.

</DOC>
<DOC>
<DOCNO> 69579 </DOCNO>
CP Violation in $\Lambda$ to p $\pi^-$: SM vs New Physics


  I discuss CP violation in $\Lambda$ to p $\pi^-$ comparing the standard model
expectations with what could happen in new physics scenarios. I point out that
Fermilab experiment E871 is sensitive to some of these scenarios.

</DOC>
<DOC>
<DOCNO> 99521 </DOCNO>
The supremum of Brownian local times on Holder curves


  For $f: [0,1]\to \R$, we consider $L^f_t$, the local time of space-time
Brownian motion on the curve $f$. Let $\sS_\al$ be the class of all functions
whose H\"older norm of order $\al$ is less than or equal to 1. We show that the
supremum of $L^f_1$ over $f$ in $\sS_\al$ is finite is $\al>\frac12$ and
infinite if $\al<\frac12$.

</DOC>
<DOC>
<DOCNO> 80995 </DOCNO>
Effective Z(2) Spin Models of Deconfinement and Percolation in SU(2)


  Effective theories are helpful tools to gain an intuitive insight into
phenomena governed by complex laws. In this work we show by means of Monte
Carlo simulations that Z(2) spin models with only spin-spin interactions
approximate rather well the critical behavior of SU(2) gauge theory at finite
temperature. These models are then used to formulate an effective description
of Polyakov loop percolation, which is shown to reproduce the thermal critical
behaviour of SU(2) gauge theory.

</DOC>
<DOC>
<DOCNO> 9958 </DOCNO>
On nonlinear susceptibility in supercooled liquids


  In this paper, we discuss theoretically the behavior of the four point
nonlinear susceptibility and its associated correlation length for supercooled
liquids close to the Mode Coupling instability temperature $T_c$. We work in
the theoretical framework of the glass transition as described by mean field
theory of disordered systems, and the hypernetted chain approximation. Our
results give an interpretation framework for recent numerical findings on
heterogeneities in supercooled liquid dynamics.

</DOC>
<DOC>
<DOCNO> 151481 </DOCNO>
Conformal superfields and BPS states in AdS_4/7 geometries


  We carry out a general analysis of the representations of the superconformal
algebras OSp(8/4,R) and OSp(8*/2N) in terms of harmonic superspace. We present
a construction of their highest-weight UIR's by multiplication of the different
types of massless conformal superfields ("supersingletons"). Particular
attention is paid to the so-called "short multiplets". Representations
undergoing shortening have "protected dimension" and may correspond to BPS
states in the dual supergravity theory in anti-de Sitter space. These results
are relevant for the classification of multitrace operators in boundary
conformally invariant theories as well as for the classification of AdS black
holes preserving different fractions of supersymmetry.

</DOC>
<DOC>
<DOCNO> 122955 </DOCNO>
Ultraviolet and Optical Observations of OB Associations and Field Stars


  Using photometry from the Ultraviolet Imaging Telescope (UIT) and photometry
and spectroscopy from three ground-based optical datasets we have analyzed the
stellar content of OB associations and field areas in and around the regions N
79, N 81, N 83, and N 94 in the LMC. We compare data for the OB association
Lucke-Hodge 2 (LH 2) to determine how strongly the initial mass function (IMF)
may depend on different photometric reductions and calibrations. We also
correct for the background contribution of field stars, showing the importance
of correcting for field star contamination in determinations of the IMF of star
formation regions. It is possible that even in the case of an universal IMF,
the variability of the density of background stars could be the dominant factor
creating the differences between calculated IMFs for OB associations.
   We have also combined the UIT data with the Magellanic Cloud Photometric
Survey to study the distribution of the candidate O-type stars in the field. We
find a significant fraction, roughly half, of the candidate O-type stars are
found in field regions, far from any obvious OB associations. These stars are
greater than 2 arcmin (30 pc) from the boundaries of existing OB associations
in the region, which is a distance greater than most O-type stars with typical
dispersion velocities will travel in their lifetimes. The origin of these
massive field stars (either as runaways, members of low-density star-forming
regions, or examples of isolated massive star formation) will have to be
determined by further observations and analysis.

</DOC>
<DOC>
<DOCNO> 69384 </DOCNO>
Studying Indirect Violation of CP, T and CPT in a B-factory


  In this work we analyze the observable asymmetries one can build from
entangled B-meson states, in order to extract information on the parameters
epsilon and delta which govern indirect violation of discrete symmetries. The
traditionally proposed observables, based on flavour tags, are not helpful for
the study of the Bd-system, where the tiny value of the width difference
between physical states clears up such asymmetry effects. Our study makes
instead use of CP tags in order to build new asymmetries where the different
parameters can be separated out. For this separation, it is decisive to achieve
a good time resolution in the measurement of entangled state decays.
Nevertheless, even with no temporal information, as would be the case in a
symmetric factory, it is still possible to extract some information on the
symmetries of the system. We discuss both genuine and non-genuine observables,
depending on whether absorptive parts can mimic or not asymmetry effects.

</DOC>
<DOC>
<DOCNO> 71443 </DOCNO>
Progress towards 2 to 2 scattering at two-loops


  We discuss the two-loop integrals necessary for evaluating massless 2 to 2
scattering amplitudes. As a test process, we consider the leading colour
two-loop contribution to qqbar to q'qbar'. We show that for physical scattering
processes the two Smirnov-Veretin planar box graphs I1 and I2 are accompanied
by factors of 1/(D-4) thereby necessitating a knowledge of both I1 and I2 to
O(epsilon). Using an alternative basis I1 and the irreducible numerator
integral I3, the factors of 1/(D-4) disappear.

</DOC>
<DOC>
<DOCNO> 9930 </DOCNO>
Non-abelian statistics of half-quantum vortices in p-wave


  Excitation spectrum of a half-quantum vortex in a p-wave superconductor
contains a zero-energy Majorana fermion. This results in a degeneracy of the
ground state of the system of several vortices. From the properties of the
solutions to Bogoliubov-de-Gennes equations in the vortex core we derive the
non-abelian statistics of vortices identical to that for the Moore-Read
(Pfaffian) quantum Hall state.

</DOC>
<DOC>
<DOCNO> 100660 </DOCNO>
Narrow operators and rich subspaces of Banach spaces with the Daugavet


  Let $X$ be a Banach space. We introduce a formal approach which seems to be
useful in the study of those properties of operators on $X$ which depend only
on the norms of images of elements. This approach is applied to the Daugavet
equation for norms of operators; in particular we develop a general theory of
narrow operators and rich subspaces of $X$ previously studied in the context of
the classical spaces $C(K)$ and $L_1(\mu)$.

</DOC>
<DOC>
<DOCNO> 170458 </DOCNO>
Reply to "Comment on: A Quantum Approach to Static Games of Complete


  This is a reply to the paper by S.C.Benjamin, quant-ph/0008127.

</DOC>
<DOC>
<DOCNO> 122734 </DOCNO>
An imaging and spectroscopic study of the very metal-deficient blue


  We present a spectrophotometric study based on VLT/FORS I observations of one
of the most metal-deficient blue compact dwarf (BCD) galaxies known, Tol
1214-277 (Z ~ Zsun/25). The data show that roughly half of the total luminosity
of the BCD originates from a bright and compact starburst region located at the
northeastern tip of a faint dwarf galaxy with cometary appearance. The
starburst has ignited less than 4 Myr ago and its emission is powered by
several thousands O7V stars and ~ 170 late-type nitrogen Wolf-Rayet stars
located within a compact region with < 500 pc in diameter. For the first time
in a BCD, a relatively strong [Fe V] 4227 emission line is seen which together
with intense He II 4686 emission indicates the presence of a very hard
radiation field in Tol 1214-277. We argue that this extraordinarily hard
radiation originates from both Wolf--Rayet stars and radiative shocks in the
starburst region. The structural properties of the low-surface-brightness (LSB)
component underlying the starburst have been investigated by means of surface
photometry down to 28 B mag/sq.arcsec. We find that, for a surface brightness
level fainter than ~ 24.5 B mag/sq.arcsec, an exponential fitting law provides
an adequate approximation to its radial intensity distribution. The broad-band
colors in the outskirts of the LSB component of Tol 1214-277 are nearly
constant and are consistent with an age below one Gyr. This conclusion is
supported by the comparison of the observed spectral energy distribution (SED)
of the LSB host with theoretical SEDs.

</DOC>
<DOC>
<DOCNO> 10049 </DOCNO>
Entrapment of a Network of Domain Walls


  We explore the idea of a network of defects to live inside a domain wall in
models of three real scalar fields, engendering the Z_2 x Z_3 symmetry. The
field that governs the Z_2 symmetry generates a domain wall, and entraps the
hexagonal network formed by the three-junctions of the model of two scalar
fields that describes the remaining Z_3 symmetry. If the host domain wall bends
to the spherical form, in the thin wall approximation there may appear
non-topological structures hosting networks that accept diverse patterns. If
Z_3 is also broken, the model may generate a buckyball containing sixty
junctions, a fullerene-like structure. Applications to cosmology are outlined.

</DOC>
<DOC>
<DOCNO> 151193 </DOCNO>
Operator Product Expansion of the Lowest Weight CPOs in N=4 SYM_4 at


  We present a detailed analysis of the 4-point functions of the lowest weight
chiral primary operators $O^{I} \sim \tr \phi^{(i}\phi^{j)}$ in $\N =4$ SYM$_4$
at strong coupling and show that their structure is compatible with the
predictions of AdS/CFT correspondence. In particular, all power-singular terms
in the 4-point functions exactly coincide with the contributions coming from
the conformal blocks of the CPOs, the R-symmetry current and the stress tensor.
Operators dual to string modes decouple at strong coupling. We compute the
anomalous dimensions and the leading $1/N^2$ corrections to the normalization
constants of the 2- and 3-point functions of scalar and vector double-trace
operators with approximate dimensions 4 and 5 respectively. We also find that
the conformal dimensions of certain towers of double-trace operators in the
{\bf 105}, {\bf 84} and {\bf 175} irreps are non-renormalized. We show that,
despite the absence of a non-renormalization theorem for the double-trace
operator in the {\bf 20} irrep, its anomalous dimension vanishes. As
by-products of our investigation, we derive explicit expressions for the
conformal block of the stress tensor, and for the conformal partial wave
amplitudes of a conserved current and of a stress tensor in $d$ dimensions.

</DOC>
<DOC>
<DOCNO> 151741 </DOCNO>
On the Holographic Principle in a Radiation Dominated Universe


  The holographic principle is studied in the context of a $n+1$ dimensional
radiation dominated closed Friedman-Robertson-Walker (FRW) universe. The
radiation is represented by a conformal field theory with a large central
charge. Following recent ideas on holography, it is argued that the entropy
density in the early universe is bounded by a multiple of the Hubble constant.
The entropy of the CFT is expressed in terms of the energy and the Casimir
energy via a universal Cardy formula that is valid for all dimensions. A new
purely holographic bound is postulated which restricts the sub-extensive
entropy associated with the Casimir energy. Unlike the Hubble bound, the new
bound remains valid throughout the cosmological evolution. When the new bound
is saturated the Friedman equation exactly coincides with the universal Cardy
formula, and the temperature is uniquely fixed in terms of the Hubble parameter
and its time-derivative.

</DOC>
<DOC>
<DOCNO> 116467 </DOCNO>
"Violating'' Clauser-Horne inequalities within classical mechanics


  Some authors have raised the question whether the probabilities stemming from
a quantum mechanical computation are entitled to enter the Bell and the
Clauser-Horne inequalities. They have remarked that if the quantum
probabilities are given the status of conditional ones and the statistics for
the various settings of the detectors in a given experiment is properly kept
into account, the inequalities happen to be no longer violated. In the present
paper a classical simile modeled after the quantum mechanical instances is
closely scrutinised. It is shown that the neglect of the conditional character
of the probabilities in the classical model leads not only to ``violate'' the
Clauser-Horne inequalities, but also to contradict the very axioms of classical
probability theory.

</DOC>
<DOC>
<DOCNO> 72196 </DOCNO>
$B \to \pi\pi$ Decay in QCD


  A new method is suggested to calculate the $B\to \pi\pi$ hadronic matrix
elements from QCD light-cone sum rules. To leading order in $\alpha_s$ and
$1/m_b$, the sum rule reproduces a factorizable matrix element, in accordance
with the prediction of the QCD factorization approach. Whereas the QCD
factorization can only take into account the nonfactorizable corrections
induced by hard-gluon exchanges, the method suggested here also allows a
systematic inclusion of soft-gluon effects. In this paper, I concentrate on the
latter aspect and present a calculation of the nonfactorizable soft-gluon
exchange contributions to $B\to \pi\pi$. The result, including twist 3 and 4
terms, is suppressed by one power of $1/m_b$ with respect to the factorizable
amplitude. Despite its numerical smallness, the soft effect is at the same
level as the $O(\alpha_s)$ correction to the QCD factorization formula for
$B\to \pi\pi$. The method suggested here can be applied to matrix elements of
different topologies and operators and to various other B-decay channels. I
also comment on the earlier applications of QCD sum rules to nonleptonic decays
of heavy mesons.

</DOC>
<DOC>
<DOCNO> 122684 </DOCNO>
The statistics of wide-separation lenses


  The probability that high-redshift sources are gravitationally-lensed with
large image separations (i.e., greater than can be produced by galactic
deflectors) is determined by the cosmological population of group- and
cluster-sized halos. Thus the observed frequency of wide-separation lensed
quasars can be used to constrain not only the halo distribution, but also a
number of cosmological parameters. A calculation of the optical depth due to
collapsed, isothermal halos is a useful guide to the lens statistics, and
illustrates that the number of wide-separation lenses is a sensitive probe of
the mean density of the universe and the present day density variance whilst
being nearly independent of the cosmological constant.

</DOC>
<DOC>
<DOCNO> 118663 </DOCNO>
VLBI Astrometry of the Stellar Image of U Herculis, Amplified by the


  The OH 1667 MHz maser in the circumstellar shell around the Mira variable U
Herculis has been observed with the NRAO Very Long Baseline Array (VLBA) at 6
epochs, spread over 4 years. Using phase referencing techniques the position of
the most blue-shifted maser spot was monitored with respect to two
extra-galactic radio sources. The absolute radio positions of the maser can be
compared with the stellar optical position measured by the Hipparcos satellite
to 15 mas accuracy. This confirms the model in which one of the maser spots
corresponds to the stellar continuum, amplified by the maser. The stellar
proper motion and the annual parallax (5.3 +/- 2.1 mas) were measured.

</DOC>
<DOC>
<DOCNO> 100540 </DOCNO>
Relations among Heegner Cycles on families of abelian surfaces


  We compute relations of rational equivalence among special codimensional two
cycles on families of abelian surfaces using elements of higher chow groups.

</DOC>
<DOC>
<DOCNO> 178799 </DOCNO>
Eta Production in Hadronic Interactions


  A short, and definitely not a complete representation of \eta production
processes on hadrons is given. First of all, the different ways of obtaining
the \pi N \to \eta N and \pi N \to \eta N amplitudes are presented. After that,
an overview of results obtained using these amplitudes as input for calculating
processes like: NN \to \eta NN, pd \to \eta ^{3}He, \pi d \to \eta NN and \eta
d, \eta ^{3}He and \eta ^{4}He as well as \eta-light nuclei bond states, will
be given. The experimental and theoretical results will be reviewed. The opened
problems and the way how to solve them will be presented.

</DOC>
<DOC>
<DOCNO> 116616 </DOCNO>
The Theory of Fractal Time: Field Equations (the Theory of Almost


  Field equations in four order derivatives with respect to time and space
coordinates based on modified classic relativistic energy of the fractal theory
of time and space are received. It is shown appearing of new spin
characteristics and new fields with imaginary energies .

</DOC>
<DOC>
<DOCNO> 68552 </DOCNO>
Pomeron intercepts at colliders


  A method allowing for a direct comparison of data with theoretical
predictions is proposed for forward jet production at HERA and Mueller-Navelet
jets at Tevatron and LHC. An application to the determination of the effective
Pomeron intercept in the BFKL-LO parametrization from d sigma/dx data at HERA
leads to a good fit with a significantly higher effective intercept, $\alpha_P=
1.43 \pm 0.025 (stat.) \pm 0.025 (syst.),$ than for proton (total and
diffractive) structure functions. It is however less than the value of the
pomeron intercept using dijets with large rapidity intervals obtained at
Tevatron. We also evaluate the rapidity veto contribution to the higher order
BFKL corrections. We suggest to measure the dependence of the dijet
cross-sections as a function of the jet transverse energies as a signal for
BFKL pomeron at LHC.

</DOC>
<DOC>
<DOCNO> 70111 </DOCNO>
QCD Instantons and the Soft Pomeron


  We study the role of semi-classical QCD vacuum solutions in high energy
scattering by considering the instanton contribution to hadronic cross
sections. We propose a new type of instanton-induced interactions (``instanton
ladder'') that leads to the rising with energy hadronic cross section of Regge
type (the Pomeron). We argue that this interaction may be responsible for the
structure of the soft Pomeron. The intercept is calculated. It has a
non-analytic dependence on the strong coupling constant, allowing a
non-singular continuation into the non-perturbative region. We derive the
Pomeron trajectory, which appears to be approximately linear in some range of
(negative) momentum transfer t, but exhibits a curvature at small t. Possible
role of instantons in multiparticle production is also discussed.

</DOC>
<DOC>
<DOCNO> 69740 </DOCNO>
KN interaction in the quark-gluon exchange framework


  The general meson-baryon potential obtained in the context of the Fock-Tani
formalism is applied in the $K^{+}N$ system. A simple spin-dependent
interaction on quark level is used in order to compare with known results. The
short range nature of the equivalent local potential is shown.

</DOC>
<DOC>
<DOCNO> 40207 </DOCNO>
D-pi Production Correlations in 500 GeV pi- N Interactions


  We study the charge correlations between charm mesons produced in 500 GeV pi-
N interactions and the charged pions produced closest to them in phase space.
With 110,000 fully reconstructed D mesons from experiment E791 at Fermilab, the
correlations are studied as functions of the D-pi - D mass difference and of
Feynman x. We observe significant correlations which appear to originate from a
combination of sources including fragmentation dynamics, resonant decays, and
charge of the beam.

</DOC>
<DOC>
<DOCNO> 85613 </DOCNO>
A Quintessence Scalar Field in Brans-Dicke Theory


  It is shown that a minimally coupled scalara field in Brans-Dicke theory
yields a non-decelerated expansion for the present universe for open, flat and
closed Friedmann-Robertson-Walker models.

</DOC>
<DOC>
<DOCNO> 7919 </DOCNO>
Off-Equilibrium Effective Temperature in Monatomic Lennard-Jones Glass


  The off-equilibrium dynamics of a monatomic Lennard-Jones glass is
investigated after sudden isothermal density jumps (crunch) from well
equilibrated liquid configurations towards the glassy state. The generalized
fluctuation-dissipation relation has been studied and the temperature
dependence of the violation factor m is found in agreement with the one step
replica symmetry breaking scenario, i.e. at low temperature m(T) is found
proportional to T up to an off-equilibrium effective temperature T_eff, where
m(T_eff)=1. We report T_eff as a function of the density and compare it with
the glass transition temperatures T_g as determined by equilibrium
calculations.

</DOC>
<DOC>
<DOCNO> 71356 </DOCNO>
Debye Screening in the QCD plasma


  Various definitions for the QCD Debye mass and its evaluation are reviewed in
a non-perturabtive framework for the study of screening of general static
sources. While it is possible to perturbatively integrate over scales $\sim T$
and thus construct a 3d effective theory, the softer scales $\sim gT$ and $\sim
g^2T$ are strongly coupled for temperatures $\lsim 10^7$ GeV and require
lattice simulations. Within the effective theory, a lattice treatment of
screening at finite quark densities $\mu \lsim 4/T$ is also possible.

</DOC>
<DOC>
<DOCNO> 12749 </DOCNO>
Roughening of close-packed singular surfaces


  An upper bound to the roughening temperature of a close-packed singular
surface, fcc Al (111), is obtained via free energy calculations based on
thermodynamic integration using the embedded-atom interaction model. Roughening
of Al (111) is predicted to occur at around 890 K, well below bulk melting (933
K), and it should therefore be observable, save for possible kinetic hindering.

</DOC>
<DOC>
<DOCNO> 151853 </DOCNO>
Boundary States in B-Field Background


  We consider the boundary states which describe D-branes in a constant B-field
background. We show that the two-form field Phi, which interpolates commutative
and noncommutative descriptions of D-branes, can be interpreted as the
invariant field strength in the T-dual picture. We also show that the extended
algebra parametrized by theta and Phi naturally appears as the commutation
relations of the original and the T-dual coordinates.

</DOC>
<DOC>
<DOCNO> 68714 </DOCNO>
Weyl Invariant Formulation of Flux-Tube Solution in the Dual


  The flux-tube solution in the dual Ginzburg-Landau (DGL) theory in the
Bogomol'nyi limit is studied by using the manifestly Weyl invariant form of the
DGL Lagrangian. The dual gauge symmetry is extended to $[U(1)]_m^3$, and
accordingly, there appear three different types of the flux-tube. The string
tension for each flux-tube is calculated analytically and is found to be the
same owing to the Weyl symmetry. It is suggested that the flux-tube can be
treated in quite a similar way with the Abrikosov-Nielsen-Olesen vortex in the
U(1) Abelian Higgs theory except for various types of flux-tube.

</DOC>
<DOC>
<DOCNO> 99429 </DOCNO>
Artinian algebras and differential forms


  This article concerns commutative algebras over a field $k$ of characteristic
zero which are finite dimensional as vectorspaces, and particularly those of
such algebras which are graded. Here the term graded is applied to
non-negatively graded algebras $A$ with $A_0$ reduced and finite dimensional.
Thus the trivial grading $A=A_0$ is only allowed if $A$ is a product of finite
field extensions of $k$. It has been conjectured (G. Corti\~nas, S. Geller, C.
Weibel; The Artinian Berger Conjecture. Math. Zeitschrift {\bf 228} 3 (1998)
569-588) that for all finite dimensional algebras $A$ which are not principal
ideal algebras (i.e. have at least one nonprincipal ideal), the following
submodule of the K\"ahler differentials is nonzero: $$\bigcap{\ker(\Omega_A
@>>>\Omega_B)}$$ Here the intersection is taken over all principal ideal
algebras $B$ and all homomorphisms $A @>>>B$. In this paper we prove that the
conjecture holds for both Gorenstein graded and standard graded algebras.

</DOC>
<DOC>
<DOCNO> 69380 </DOCNO>
$\Delta G(x,\mu^2)$ from jet and prompt photon production at RHIC


  We compare theoretical results for jet and prompt photon production in
polarized pp-collisions at RHIC obained with three different methods: a) the
unpolarized event generator PYTHIA combined with hadronic asymmetry weights
calculated from leading order formulae, b) the polarized event generator SPHINX
which treats the partonic helicity in the hard scattering and the initial state
shower explicitly, and c) parton generators which integrate next-to-leading
order QCD cross sections using Monte Carlo methods. Method a) requires far less
computer time than method b) but we find that it is too imprecise for precision
studies. The lacking treatment of partonic polarization in the initial state
shower results in relative deviations in the asymmetries of up to 20% relative
to SPHINX (method b)). As was to be expected, the event generator predictions
for the absolute cross sections differ significantly from the next-to-leading
order QCD calculations. But fortunately the asymmetries show a much better
agreement: relative deviations for prompt photon production for
parameterizations with medium and large $\Delta g(x,\mu^2)$ barely exceed 10%.
After fine tuning the parameters of the parton showers the same result can be
obtained for jet production.

</DOC>
<DOC>
<DOCNO> 117369 </DOCNO>
Interferometric 12CO Observations of the Central Disk of NGC 4631: An


  We present interferometric observations of CO J=1-0 emission in the central
regions of the edge-on galaxy NGC 4631, known for its extended gaseous halo and
its tidal interactions. Previous single-dish observations revealed that almost
all of the CO emission arises from a central ring or bar-like structure of
length $\sim$ 4 kpc. We confirm this structure at higher resolution, and find
that it is bent at the center, reflecting the overall bend in this galaxy
apparent from optical images. The kinematic evidence favors a rigidly rotating
ring over a bar. The gaseous halo emission in several tracers is concentrated
above and below this molecular structure. To the north of an emission peak at
the eastern end of the structure is an extraplanar feature showing filamentary
and shell-like properties which we interpret as an energetic molecular outflow.
The energies involved are difficult to estimate, but are probably of order
10$^{54}$ ergs or more. The CO concentration in the disk below this structure
coincides with a bright HII region complex, a peak of radio emission, and the
brightest X-ray feature in the inner disk of the galaxy seen in a ROSAT HRI
map, all suggesting intense star formation. A filament of radio continuum
emission may also have a footprint in this region of the disk. The origin of
the outflow is unclear.

</DOC>
<DOC>
<DOCNO> 99779 </DOCNO>
A proof of the weak (1,1) inequality for singular integrals with non


  Given a doubling measure $\mu$ on $R^d$, it is a classical result of harmonic
analysis that Calderon-Zygmund operators which are bounded in $L^2(\mu)$ are
also of weak type (1,1). Recently it has been shown that the same result holds
if one substitutes the doubling condition on $\mu$ by a mild growth condition
on $\mu$. In this paper another proof of this result is given. The proof is
very close in spirit to the classical argument for doubling measures and it is
based on a new Calderon-Zygmund decomposition adapted to the non doubling
situation.

</DOC>
<DOC>
<DOCNO> 11890 </DOCNO>
Computer-Generated Holographic Optical Tweezer Arrays


  Holographic techniques significantly extend the capabilities of laser
tweezing, making possible extended trapping patterns for manipulating large
numbers of particles and volumes of soft matter. We describe practical methods
for creating arbitrary configurations of optical tweezers using
computer-generated diffractive optical elements. While the discussion focuses
on ways to create planar arrays of identical tweezers, the approach can be
generalized to three-dimensional arrangements of heterogeneous tweezers and
extended trapping patterns.

</DOC>
<DOC>
<DOCNO> 100918 </DOCNO>
Ljusternik-Schnirelmann Categories, Links and Relations


  This paper is concerned with some well-known Ljusternik-Schnirelmann
categories. We desire to find some links and relations among them. This has
been done by using the concepts of precategoty, T-collection and closure of a
category.

</DOC>
<DOC>
<DOCNO> 13713 </DOCNO>
Ising Meets Ornstein and Zernike, Debye and Huckel, Widom and Rowlinson,


  The name Ising has come to stand not only for a specific model, but for an
entire universality class - arguably the most important such class - in the
theory of critical phenomena. I review several examples, both in and out of
equilibrium, in which Ising universality appears or is pertinent. The
"Ornstein-Zernike" connection concerns a thermodynamically self-consistent
closure of the eponymous relation, which lies at the basis of the modern theory
of liquids, as applied to the Ising lattice gas. Debye and Huckel founded the
statistical mechanics of ionic solutions, which, despite the long-range nature
of the interaction, now appear to exhibit Ising-like criticality. The model of
Widom and Rowlinson involves only excluded-volume interactions between unlike
species, but again belongs to the Ising universality class.
Far-from-equilibrium models of voting behavior, catalysis, and hysteresis
provide further examples of this ubiquitous universality class.

</DOC>
<DOC>
<DOCNO> 11015 </DOCNO>
Reflection High-Energy Electron Diffraction oscillations during


  Pulsed Laser Deposition in molecular-beam epitaxy environment (Laser-MBE) has
been used to grow high quality BaCuOx/CaCuO2 superlattices. In situ Reflection
High Energy Electron Diffraction (RHEED) shows that the growth mechanism is
2-dimensional. Furthermore, weak but reproducible RHEED intensity oscillations
have been monitored during the growth. Ex-situ x-ray diffraction spectra
confirmed the growth rate deduced from RHEED oscillations. Such results
demonstrate that RHEED oscillations can be used, even for (BaCuOx)2/(CaCuO2)2
superlattices, for phase locking of the growth.

</DOC>
<DOC>
<DOCNO> 100517 </DOCNO>
The empirical values of the critical k-SAT exponents are wrong


  There has been much recent interest in the satisfiability of random Boolean
formulas. A random k-SAT formula is the conjunction of m random clauses, each
of which is the disjunction of k literals (a variable or its negation). It is
known that when the number of variables n is large, there is a sharp transition
from satisfiability to unsatisfiability; in the case of 2-SAT this happens when
m/n --> 1, for 3-SAT the critical ratio is thought to be m/n \approx 4.2. The
sharpness of this transition is characterized by a critical exponent, sometimes
called \nu=\nu_k. An article in the journal Science reported a detailed study
of \nu, in which it was estimated that \nu_3 = 1.5+-0.1, \nu_4 = 1.25+-0.05,
\nu_5 = 1.1+-0.05, \nu_6 = 1.05+-0.05, and \nu_k --> 1 as k --> infinity.
Similar estimates are given in a number of other articles as well. We give here
a simple proof that each of these exponents is at least 2 (provided the
exponent is well-defined). This result holds for each of the three standard
ensembles of random k-SAT formulas: m clauses selected uniformly at random
without replacement, m clauses selected uniformly at random with replacement,
and each clause selected with probability p independent of the other clauses.
We also obtain similar results for q-colorability and the appearance of a
q-core in a random graph.

</DOC>
<DOC>
<DOCNO> 10416 </DOCNO>
Bose-Einstein condensation thermodynamics of a trapped gas with


  We study the Bose-Einstein condensation of an interacting gas with attractive
interaction confined in a harmonic trap using a semiclassical two-fluid
mean-field model. The condensed state is described by converged numerical
solution of the Gross-Pitaevskii equation. By solving the system of coupled
equations of this model iteratively we obtain converged results for the
temperature dependencies of the condensate fraction, chemical potential, and
internal energy for the Bose-Einstein condensate of $^7$Li atoms.

</DOC>
<DOC>
<DOCNO> 102004 </DOCNO>
A New Cyclic Module for Hopf Algebras


  We define a new cyclic module, dual to the Connes-Moscovici cyclic module,
for Hopf algebras, and give a characteristric map for the coaction of Hopf
algebras. We also compute the resulting cyclic homology for cocommutative Hopf
algebras, and some quantum groups.

</DOC>
<DOC>
<DOCNO> 151572 </DOCNO>
$\phi^4$ Field theory on a Lie group


  The $\phi^4$ field model is generalized to the case when the field $\phi(x)$
is defined on a Lie group: $S[\phi]=\int_{x\in G} L[\phi(x)] d\mu(x)$,
$d\mu(x)$ is the left-invariant measure on a locally compact group $G$. For the
particular case of the affine group $G:x'=ax+b,a\in\R_+, x,b \in \R^n$ t he
Feynman perturbation expansion for the Green functions is shown to have no
ultra-violet divergences for certain choice of $\lambda(a) \sim a^\nu$.

</DOC>
<DOC>
<DOCNO> 151363 </DOCNO>
Exact Solutions of the SU(2) Yang-Mills-Higgs Theory


  Some exact static solutions of the SU(2) Yang-Mills-Higgs theory are
presented. These solutions satisfy the first order Bogomol'nyi equations, and
possess infinite energies. They are axially symmetric and could possibly
represent monopoles and an antimonopole sitting on the z-axis.

</DOC>
<DOC>
<DOCNO> 170705 </DOCNO>
Time and Information


  The relationship between 'information' and 'time' is explored in order to
look for a 'solution' to the 'Problem of Time'. 'Time' is found to be the
result of the conversion of energy into 'information'. The 'time' number or
label we assign to 'events' can be manufactured by processing information
'flowing' from a Feynman Clock (FC), via a 'signal', to a Feynman Detector (FD)
in causal networks. Macroscopic arrows of time are built from the irreversible
Quantum Arrow of Time (QAT) associated with unstable or excited states of
quantum systems. The QAT is shown to be connected to the thermodynamic arrow of
time. Collective Excitations, and causal networks provide a means for
understanding 'time' in complex systems. The ordered set of the 'time' numbers
labeling 'events' can be used to construct the 'direction' and 'dimension'
associated with the usual conception of a 'time' axis or 'time' coordinate in
quantum, classical and realtivistic mechanics.

</DOC>
<DOC>
<DOCNO> 69544 </DOCNO>
Anisotropic flow in ultra-relativistic heavy ion collisions


  A sign reversal of the directed flow parameter $v_1$ in the central rapidity
region in Au+Au collisions at $\sqrt s =200$~AGeV is predicted. This anti-flow
is shown to be linked to the expansion of the hot matter created. In line with
this observation the predicted elliptic flow parameter $v_2$ of various
particle species is predicted and linked to the mean free path of these
particles.

</DOC>
<DOC>
<DOCNO> 119838 </DOCNO>
Investigating the structure of the accretion disk in WZ Sge from


  We present our second paper describing multi-wave-band, time-resolved
spectroscopy of WZ Sge. We analyze the evolution of both optical and IR
emission lines throughout the orbital period and find evidence, in the Balmer
lines, for an optically thin accretion disk and an optically thick hot-spot.
Optical and IR emission lines are used to compute radial velocity curves. Fits
to our radial velocity measurements give an internally inconsistent set of
values for K1, gamma, and the phase of red-to-blue crossing. We present a
probable explanation for these discrepancies and provide evidence for similar
behaviour in other short orbital period dwarf-novae. Selected optical and IR
spectra are measured to determine the accretion disk radii. Values for the disk
radii are found to be strongly dependent on the assumed WD mass and binary
orbital inclination. However, the separation of the peaks in the optical
emission line (i.e. an indication of the outer disk radius) has been found to
be constant during all phases of the super-cycle period over the last 40 years.

</DOC>
<DOC>
<DOCNO> 7906 </DOCNO>
QCD-like Theories at Finite Baryon Density


  We study QCD-like theories with pseudoreal fermions at finite baryon density.
Such theories include two-color QCD with quarks in the fundamental
representation of the color group as well as any-color QCD with quarks in the
adjoint color representation. In all such theories the lightest baryons are
diquarks. At zero chemical potential $\mu$ they are, together with the
pseudoscalar mesons, the Goldstone modes of a spontaneously broken enlarged
chiral symmetry group. Using symmetry principles, we derive the low-energy
effective Lagrangian for these particles. We find that a second order phase
transition occurs at a value of $\mu$ equal to half the mass of the Goldstone
modes. For values of $\mu$ beyond this point the scalar diquarks Bose condense
and the diquark condensate is nonzero. We calculate the dependence of the
chiral condensate, the diquark condensate, the baryon charge density, and the
masses of the diquark and pseudoscalar excitations on $\mu$ at finite bare
quark mass and scalar diquark source. The relevance of our results to lattice
QCD calculations and to real three-color QCD at finite baryon density is
discussed.

</DOC>
<DOC>
<DOCNO> 83223 </DOCNO>
C++ programming language for an abstract massively parallel SIMD


  The aim of this work is to define and implement an extended C++ language to
support the SIMD programming paradigm. The C++ programming language has been
extended to express all the potentiality of an abstract SIMD machine consisting
of a central Control Processor and a N-dimensional toroidal array of Numeric
Processors. Very few extensions have been added to the standard C++ with the
goal of minimising the effort for the programmer in learning a new language and
to keep very high the performance of the compiled code. The proposed language
has been implemented as a porting of the GNU C++ Compiler on a SIMD
supercomputer.

</DOC>
<DOC>
<DOCNO> 150577 </DOCNO>
The Structure of the D0-D4 Bound State


  We derive a set of equations for the wavefunction describing the marginal
bound state of a single D0-brane with a single D4-brane. These are equations
determining the vacuum of an N=8 abelian gauge theory with a charged
hypermultiplet. We then solve these equations for the most general possible
zero-energy solution using a Taylor series. We find that there are an infinite
number of such solutions of which only one must be normalizable. We explore the
structure of a normalizable solution under the assumption of an asymptotic
expansion. Even the leading terms in the asymptotic series, which should
reflect the supergravity solution, are unusual. Through the $Spin(5)$ flavor
symmetry, the modes which are massive at long distance actually influence the
leading behavior. Lastly, we show that the vacuum equations can quite
remarkably be reduced to a single equation involving one unknown function. The
resulting equation has a surprisingly simple and suggestive form.

</DOC>
<DOC>
<DOCNO> 83281 </DOCNO>
Verbal Interactions in Virtual Worlds


  We first discuss respective advantages of language interaction in virtual
worlds and of using 3D images in dialogue systems. Then, we describe an example
of a verbal interaction system in virtual reality: Ulysse. Ulysse is a
conversational agent that helps a user navigate in virtual worlds. It has been
designed to be embedded in the representation of a participant of a virtual
conference and it responds positively to motion orders. Ulysse navigates the
user's viewpoint on his/her behalf in the virtual world. On tests we carried
out, we discovered that users, novices as well as experienced ones have
difficulties moving in a 3D environment. Agents such as Ulysse enable a user to
carry out navigation motions that would have been impossible with classical
interaction devices. From the whole Ulysse system, we have stripped off a
skeleton architecture that we have ported to VRML, Java, and Prolog. We hope
this skeleton helps the design of language applications in virtual worlds.

</DOC>
<DOC>
<DOCNO> 102459 </DOCNO>
Bipartite graphs with uniquely restricted maximum matchings and their


  A maximum stable set in a graph G is a stable set of maximum size. S is a
local maximum stable set if it is a maximum stable set of the subgraph of G
spanned by the union of S and N(S), where N(S) is the neighborhood of S. A
matching M is uniquely restricted if its saturated vertices induce a subgraph
which has a unique perfect matching, namely M itself. One theorem of Nemhauser
and Trotter Jr., working as a useful sufficient local optimality condition for
the weighted maximum stable set problem, ensures that any local maximum stable
set of G can be enlarged to a maximum stable set of G. In one of our previous
papers it is proven that the family of all local maximum stable sets of a
forest forms a greedoid on its vertex set. In this paper we obtain a
generalization of this assertion claiming that the family of all local maximum
stable sets of a bipartite graph G is a greedoid if and only if all maximum
matchings of G are uniquely restricted.

</DOC>
<DOC>
<DOCNO> 70639 </DOCNO>
Eigenvalues of the QCD Dirac operator at finite temperature and density


  We investigate the eigenvalue spectrum of the staggered Dirac matrix in
two-color QCD at nonzero temperature and at baryon density when the eigenvalues
become complex. The quasi-zero modes and their role for chiral symmetry
breaking and the deconfinement transition are examined. The bulk of the
spectrum and its relation to quantum chaos is considered. Comparison with
predictions from random matrix theory is presented.

</DOC>
<DOC>
<DOCNO> 84936 </DOCNO>
Quasiequilibrium sequences of synchronized and irrotational binary


  We present a numerical method to compute quasiequilibrium configurations of
close binary neutron stars in the pre-coalescing stage. A hydrodynamical
treatment is performed under the assumption that the flow is either rigidly
rotating or irrotational. The latter state is technically more complicated to
treat than the former one (synchronized binary), but is expected to represent
fairly well the late evolutionary stages of a binary neutron star system. As
regards the gravitational field, an approximation of general relativity is
used, which amounts to solving five of the ten Einstein equations (conformally
flat spatial metric). The obtained system of partial differential equations is
solved by means of a multi-domain spectral method. Two spherical coordinate
systems are introduced, one centered on each star; this results in a precise
description of the stellar interiors. Thanks to the multi-domain approach, this
high precision is extended to the strong field regions. The computational
domain covers the whole space so that exact boundary conditions are set to
infinity. Extensive tests of the numerical code are performed, including
comparisons with recent analytical solutions. Finally a constant baryon number
sequence (evolutionary sequence) is presented in details for a polytropic
equation of state with gamma=2.

</DOC>
<DOC>
<DOCNO> 84891 </DOCNO>
Global embeddings of scalar-tensor theories in (2+1)-dimensions


  We obtain (3+3)- or (3+2)-dimensional global flat embeddings of four
uncharged and charged scalar-tensor theories with the parameters B or L in the
(2+1)-dimensions, which are the non-trivially modified versions of the
Banados-Teitelboim-Zanelli (BTZ) black holes. The limiting cases B=0 or L=0
exactly are reduced to the Global Embedding Minkowski Space (GEMS) solution of
the BTZ black holes.

</DOC>
<DOC>
<DOCNO> 69041 </DOCNO>
Scalar Gluonium and Instantons


  The impact of QCD instantons on scalar glueball properties is studied in the
framework of an instanton-improved operator product expansion (IOPE) for the
0^{++} glueball correlation function. Direct instanton contributions are found
to strongly dominate over those from perturbative fluctuations and soft vacuum
fields. All IOPE sum rules, including the one involving a subtraction constant,
show a high degree of stability and are, in contrast to previous glueball sum
rules, consistent with the low-energy theorem for the zero-momentum correlator.
The predicted glueball mass m_{G}=1.53 \pm 0.2 GeV is less sensitive to the
instanton contributions then the glueball coupling (residue) f_{G}=1.01\pm 0.25
GeV, which increases by about half an order of magnitude. Both glueball
properties are shown to obey scaling relations as a function of the average
instanton size and density.

</DOC>
<DOC>
<DOCNO> 68264 </DOCNO>
Exact and Broken Symmetries in Particle Physics


  In these lectures, I discuss the role of symmetries in particle physics. I
begin by discussing global symmetries and show that they can be realized
differently in nature, depending on whether or not the vacuum state is left
invariant by the symmetry. I introduce next the notion of local symmetries and
show how these symmetries can be implemented through the introduction of gauge
fields. Using the simple example of a spontaneously broken U(1) symmetry, I
discuss the Higgs mechanism showing that it provides a natural way for the
gauge fields to acquire mass. Finally, I show how these concepts are used as
the basis for the Standard Model of particle physics, ending with a brief
description of some of the salient aspects of Quantum Chromodynamics and of the
electroweak theory.

</DOC>
<DOC>
<DOCNO> 151285 </DOCNO>
Gauge Symmetry Breakdown due to Dynamical Higgs Scalar


  Assuming dynamical spontaneous breakdown of chiral symmetry for massless
gauge theory without scalar fields, we present a method how to construct an
effective action of the dynamical Nambu-Goldstone bosons and elemetary fermions
by using auxiliary fields. Here dynamical particles are asssumed to be composed
of elementary fermions. Various quantities including decay constants are
calculated from this effective action. This technique is also applied to gauge
symmetry breakdown, $SU(5)\to SU(4)$, to obtain massive gauge fields.

</DOC>
<DOC>
<DOCNO> 70603 </DOCNO>
Theories in More than Four Dimensions


  Particle physics models where there are large hidden extra dimensions are
currently on the focus of an intense activity. The main reason is that these
large extra dimensions may come with a TeV scale for quantum gravity (or string
theory) which leads to a plethora of new observable phenomena in colliders as
well in other areas of particle physics. Those new dimensions could be as large
as millimeters implying deviations of the Newton's law of gravity at these
scales. Intending to provide a basic introduction to this fast developing area,
we present a general overview of theories with large extra dimensions. We
center our discussion on models for neutrino masses, high dimensional
extensions of the Standard Model and gauge coupling unification. We discuss the
recently proposed technic of splitting fermion wave functions on a tick brane
which may solve the problem of a fast proton decay and produce fermion mass
hierarchies without invoking extra global symmetries. Randall-Sundrum model and
some current trends are also commented.

</DOC>
<DOC>
<DOCNO> 101480 </DOCNO>
Polynomiality of the q,t-Kostka Revisited


  Let $K(q,t)= \|K_{\la\mu}(q,t)\|_{\la,\mu}$ be the Macdonald q,t-Kostka
matrix and $K(t)=K(0,t)$ be the matrix of the Kostka-Foulkes polynomials
K_{\la\mu}(t). In this paper we present a new proof of the polynomiality of the
q,t-Kostka coefficients that is both short and elementary. More precisely, we
derive that $K(q,t)$ has entries in \ZZ[q,t] directly from the fact that the
matrix $K(t)^{-1}$ has entries in \ZZ[t]. The proof uses only identities that
can be found in the original paper [7] of Macdonald.

</DOC>
<DOC>
<DOCNO> 9048 </DOCNO>
On the pseudogap phase in high-T_c superconductors


  We describe the approach of the superconducting state as a sequence of
cross-over phenomena. As the temperature is decreased, uncorrelated pairing of
the electrons leads to the opening of a pseudogap at T_F^*. Upon further
lowering the temperature those electron pairs acquire well behaved itinerant
features at T_B^*, leading to partial Meissner screening and Drude type
behavior of the optical conductivity. Further decrease of the temperature leads
to their condensation and superconductivity at T_c. The analysis is done on the
basis of the Boson-Fermion model in the cross-over regime between 2D and 3D.

</DOC>
<DOC>
<DOCNO> 8184 </DOCNO>
Formation and control of electron molecules in artificial atoms:


  Interelectron interactions and correlations in quantum dots can lead to
spontaneous symmetry breaking of the self-consistent mean field resulting in
formation of Wigner molecules. With the use of spin-and-space unrestricted
Hartree-Fock (sS-UHF) calculations, such symmetry breaking is discussed for
field-free conditions, as well as under the influence of an external magnetic
field. Using as paradigms impurity-doped (as well as the limiting case of
clean) two-electron quantum dots (which are analogs to helium-like atoms), it
is shown that the interplay between the interelectron repulsion and the
electronic zero-point kinetic energy leads, for a broad range of impurity
parameters, to formation of a singlet ground-state electron molecule,
reminiscent of the molecular picture of doubly-excited helium. Comparative
analysis of the conditional probability distributions for the sS-UHF and the
exact solutions for the ground state of two interacting electrons in a clean
parabolic quantum dot reveals that both of them describe formation of an
electron molecule with similar characteristics. The self-consistent field
associated with the triplet excited state of the two-electron quantum dot
(clean as well as impurity-doped) exhibits symmetry breaking of the Jahn-Teller
type, similar to that underlying formation of nonspherical open-shell nuclei
and metal clusters. Furthermore, impurity and/or magnetic-field effects can be
used to achieve controlled manipulation of the formation and pinning of the
discrete orientations of the Wigner molecules. Impurity effects are futher
illustrated for the case of a quantum dot with more than two electrons.

</DOC>
<DOC>
<DOCNO> 84408 </DOCNO>
Criteria for de Sitter inflation in Einstein-Cartan cosmology and COBE


  Criteria for the existence of de Sitter inflation with dilaton fields in
four-dimensional space-times with torsion is discussed.The relation between
matter density perturbation and the spin-density perturbation is stablished
based on this criteria.From COBE data it is shown that there is a linear
relationship between the spin-torsion density and temperature of the Universe
for the case where matter density dominates the kinetic part of dilaton fields.

</DOC>
<DOC>
<DOCNO> 8584 </DOCNO>
Ideally Efficient Irreversible Molecular Gears


  Typical man-made locomotive devices use reversible gears, as cranks, for
transforming reciprocating motion into directed one. Such gears are holonomic
and have the transduction efficiency of unity. On the other hand, a typical
gear of molecular motors is a ratchet rectifier, which is irreversible. We
discuss what properties of rectifier mostly influence the transduction
efficiency and show that an apliance which locks under backwards force can
achieve the energetic efficiency of unity, without approaching reversibility. A
prototype device based on ratchet principle is discussed.

</DOC>
<DOC>
<DOCNO> 71634 </DOCNO>
Enhanced Gluino Box Contribution to epsilon'/epsilon in SUSY


  We show that in supersymmetric extensions of the Standard Model gluino box
diagrams can yield a large CP-violating Delta(I)=3/2 contribution to
s->d+q(bar)+q flavor-changing neutral current processes, which feeds into the
I=2 isospin amplitude in K->pi+pi decays. This contribution only requires
moderate mass splitting between the right-handed squarks u(tilde)_R and
d(tilde)_R, and persists for squark masses of order 1 TeV. Taking into account
current bounds on Im(delta_{sd}^{LL}) from K-K(bar) mixing, the resulting
contribution to epsilon'/epsilon could naturally be an order of magnitude
larger than the measured value.

</DOC>
<DOC>
<DOCNO> 102117 </DOCNO>
Realcompactness and spaces of vector-valued functions


  It is shown that the existence of a biseparating map between a large class of
spaces of vector-valued continuous functions A(X,E) and A(Y,F) implies that
some compactifications of X and Y are homeomorphic. In some cases, conditions
are given to warrant the existence of a homeomorphism between the
realcompactifications of X and Y; in particular we find remarkable differences
with respect to the scalar context: namely, if E and F are infinite-dimensional
and T is a biseparating map between the space of E-valued bounded continuous
functions on X and that of F-valued bounded continuous functions on Y, then the
realcompactifications of X and Y are homeomorphic.

</DOC>
<DOC>
<DOCNO> 116370 </DOCNO>
The Superconducting TESLA Cavities


  The conceptional design of the proposed linear electron-positron collider
TESLA is based on 9-cell 1.3 GHz superconducting niobium cavities with an
accelerating gradient of Eacc >= 25 MV/m at a quality factor Q0 > 5E+9. The
design goal for the cavities of the TESLA Test Facility (TTF) linac was set to
the more moderate value of Eacc >= 15 MV/m. In a first series of 27
industrially produced TTF cavities the average gradient at Q0 = 5E+9 was
measured to be 20.1 +- 6.2 MV/m, excluding a few cavities suffering from
serious fabrication or material defects. In the second production of 24 TTF
cavities additional quality control measures were introduced, in particular an
eddy-current scan to eliminate niobium sheets with foreign material inclusions
and stringent prescriptions for carrying out the electron-beam welds. The
average gradient of these cavities at Q0 = 5E+9 amounts to 25.0 +- 3.2 MV/m
with the exception of one cavity suffering from a weld defect. Hence only a
moderate improvement in production and preparation techniques will be needed to
meet the ambitious TESLA goal with an adequate safety margin. In this paper we
present a detailed description of the design, fabrication and preparation of
the TESLA Test Facility cavities and their associated components and report on
cavity performance in test cryostats and with electron beam in the TTF linac.
The ongoing R&D towards higher gradients is briefly addressed.

</DOC>
<DOC>
<DOCNO> 151914 </DOCNO>
Nonperturbative Aspect In N=2 Supersymmetric Noncommutative Yang-Mills


  We investigate asymptotic behaviors of the strong coupling limit in the N=2
supersymmetric non-commutative Yang-Mills theory. The strong coupling behavior
is quite different from the commutative one since the non-commutative dual U(1)
theory is asymptotic free, although the monodoromy is the same as that of the
ordinary theory. Singularities are produced by infinitely heavy monopoles and
dyons. Nonperturbative corrections may be determined by holomorphy.

</DOC>
<DOC>
<DOCNO> 119139 </DOCNO>
Interpretation of the UV spectrum of some stars with little reddening


  The spectrum of five stars is analysed and explained by the superimposition
of two components. One is the extinction of the direct starlight, with an
extinction coefficient A which varies as the inverse of the wavelength across
all the UV. This linear dependence of extinction upon the inverse of wavelength
prolongs to the UV the well known relation which exist in the optical between
extinction and wavelength.
  The second component is an additional feature, superimposed on the extincted
direct starlight. This feature is interpreted as starlight scattered by dust at
close angular distance to the star, into the beam of the observation.

</DOC>
<DOC>
<DOCNO> 102426 </DOCNO>
Common subbundles and intersections of divisors


  Let V_0 and V_1 be complex vector bundles over a space X. We use the theory
of divisors on formal groups to give obstructions in generalised cohomology
that vanish when V_0 and V_1 can be embedded in a bundle U in such a way that
V_0\cap V_1 has dimension at least k everywhere. We study various algebraic
universal examples related to this question, and show that they arise from the
generalised cohomology of corresponding topological universal examples. This
extends and reinterprets earlier work on degeneracy classes in ordinary
cohomology or intersection theory.

</DOC>
<DOC>
<DOCNO> 170518 </DOCNO>
Classical solution of the wave equation


  The classical limit of wave quantum mechanics is analyzed. It is shown that
the general requirements of continuity and finiteness to the solution
$\psi(x)=Ae^{i\phi(x)}+ Be^{-i\phi(x)}$, where $\phi(x)=\frac 1\hbar W(x)$ and
$W(x)$ is the reduced classical action of the physical system, result in the
asymptote of the exact solution and general quantization condition for $W(x)$,
which yields the exact eigenvalues of the system.

</DOC>
<DOC>
<DOCNO> 84699 </DOCNO>
Attractor states and infrared scaling in de Sitter space


  The renormalized expectation value of the energy-momentum tensor for a scalar
field with any mass m and curvature coupling xi is studied for an arbitrary
homogeneous and isotropic physical initial state in de Sitter spacetime. We
prove quite generally that <T_{ab}> has a fixed point attractor behavior at
late times, which depends only on m and xi, for any fourth order adiabatic
state that is infrared finite. Specifically, when m^2 + xi R > 0, <T_{ab}>
approaches the Bunch-Davies de Sitter invariant value at late times,
independently of the initial state. When m = xi = 0, it approaches instead the
de Sitter invariant Allen-Folacci value. When m = 0 and xi \ge 0 we show that
this state independent asymptotic value of the energy-momentum tensor is
proportional to the conserved geometrical tensor (3)H_{ab}, which is related to
the behavior of the quantum effective action of the scalar field under global
Weyl rescaling. This relationship serves to generalize the definition of the
trace anomaly in the infrared for massless, non-conformal fields. In the case
m^2 + xi R = 0, but m and xi separately different from zero, <T_{ab}> grows
linearly with cosmic time at late times. For most values of m and xi in the
tachyonic cases, m^2 + xi R < 0, <T_{ab}> grows exponentially at late cosmic
times for all physically admissable initial states.

</DOC>
<DOC>
<DOCNO> 117557 </DOCNO>
Models of the Time Variability of BHC: Light Curves, PSD, Lags


  We present a model for the aperiodic variablity of accreting Black Hole
Candidates (BHC) along with model light curves. According to the model this
variability is the combined outcome of random (Poisson) injection of soft
photons near the center of an extended {\sl inhomogeneous} distribution of hot
electrons (similar to those advocated by the ADAF or ADIOS flows) and the
stochastic nature of Compton scattering which converts these soft photons into
the observed high energy radiation. Thus, the timing properties (PSD, lags,
coherence) of the BHC light curves reflect, to a large extent, the properties
of the scattering medium (which in this approximation acts as a combination of
a {\sl linear} amplifier/filter) and they can be used to probe its structure,
most notably the density profile of the scattering medium. The model accounts
well for the observed PSDs and lags and also the reduction in the RMS
variability and the increase in the characteristic PSD frequencies with
increasing source luminosity. The electron density profiles obtained to date
are consistent mainly with those of ADIOS but also with pure ADAF flows.

</DOC>
<DOC>
<DOCNO> 121687 </DOCNO>
The Role of Clustering of Sub-Clumps in Bright Elliptical Galaxy


  We reveal the role of clustering of sub-clumps, which is expected in the cold
dark matter (CDM) universe, in forming a bright elliptical galaxy (BEG) from a
low-spin seed galaxy.
 This can be done by comparing the evolution of a low-spin seed galaxy
including small-scale density fluctuations expected in the CDM universe
 (Model 1) with that of a completely uniform one (Model 2), using numerical
experiments.
 We show that Model 2 cannot reproduce the properties of BEGs and forms a disk
which is too compact and too bright due to the conservation of the
initial-small angular momentum.
 In Model 1 clustering of the sub-clumps caused by initial small-scale density
fluctuations leads to angular momentum transfer from the baryon component to
the dark matter and consequently a nearly spherical system supported by random
motions is formed.
 Moreover the collisionless property of the stars formed in the sub-clumps
prevents the dissipative contraction of the system, leading to a large measured
half-light radius.
 As a result, the end-product is quite well reproduces the observed properties
of BEGs, such as the de Vaucouleurs light-profile, typical color and
metallicity gradients, the large half-light radius, the small ratio of the
rotational velocity to the velocity dispersion (V/\sigma). We conclude that the
clustering of sub-clumps, i.e., the hierarchical clustering, plays a crucial
role in the formation of BEGs from a low-spin seed galaxy.

</DOC>
<DOC>
<DOCNO> 170250 </DOCNO>
The quantum bit commitment theorem


  Unconditionally secure two-party bit commitment based solely on the
principles of quantum mechanics (without exploiting special relativistic
signalling constraints, or principles of general relativity or thermodynamics)
has been shown to be impossible, but the claim is repeatedly challenged. The
quantum bit commitment theorem is reviewed here and the central conceptual
point, that an `Einstein-Podolsky-Rosen' attack or cheating strategy can always
be applied, is clarified. The question of whether following such a cheating
strategy can ever be disadvantageous to the cheater is considered and answered
in the negative. There is, indeed, no loophole in the theorem.

</DOC>
<DOC>
<DOCNO> 7817 </DOCNO>
Influence of rare regions on quantum phase transition in


  The effects of rare regions on the critical properties of quantum
antiferromagnets with hidden degrees of freedom within the renormalization
group is discussed. It is shown that for ``constrained'' systems the stability
range on the phase diagram remains the same as in the mean-field theory while
for ``unconstrained'' systems the stability range is effectively decreased.

</DOC>
<DOC>
<DOCNO> 118480 </DOCNO>
The head-tail structure of high-velocity clouds - A survey of the


  We present new observational results on high-velocity clouds (HVCs) based on
an analysis of the Leiden/Dwingeloo HI survey. We cataloged all HVCs with NHI >
1 10^19 cm^-2 and found 252 clouds that form a representative flux limited
sample. The detailed analysis of each individual HVC in this sample revealed a
significant number of HVCs (nearly 20%) having simultaneously a velocity and a
column density gradient. These HVCs have a cometary appearance in the
position-velocity representation and are called henceforward head-tail HVCs (HT
HVCs). The head is the region with the highest column density of the HVC, while
the column density of the tail is in general much lower (by a factor of 2 - 4).
The absolute majority of the cataloged HVCs belongs to the well known HVC
complexes. With exception of the very faint HVC complex L, all HVC complexes
contain HT HVCs. The HT HVCs were analyzed statistically with respect to their
physical parameters like position, velocity (v_LSR,v_GSR), and column density.
We found a linear correlation between the fraction of HVCs having a head-tail
structure and the peak column density of the HVCs. While there is no
correlation between the fraction of HT HVCs and v_LSR, we found a dependence of
the fraction of HT HVCs and v_GSR. There is no significant correlation between
the fraction of HT HVCs and the parameters galactic longitude and latitude. The
HT HVCs may be interpreted as HVCs that are currently interacting with their
ambient medium. In the context of this model the tails represent material that
is stripped off from the HVC core. We discuss the implications of this model
for galactic and extragalactic HVCs.

</DOC>
<DOC>
<DOCNO> 119029 </DOCNO>
A Tunable Echelle Imager


  We describe and evaluate a new instrument design called a Tunable Echelle
Imager (TEI). In this instrument, the output from an imaging Fabry-Perot
interferometer is cross-dispersed by a grism in one direction and dispersed by
an echelle grating in the perpendicular direction. This forms a mosaic of
different narrow-band images of the same field on a detector. It offers a
distinct wavelength multiplex advantage over a traditional imaging Fabry-Perot
device.
  Potential applications of the TEI include spectrophotometric imaging and
OH-suppressed imaging by rejection.

</DOC>
<DOC>
<DOCNO> 101144 </DOCNO>
Families of affine planes: the existence of a cylinder


  Given a family of complex affine planes, we show that it is trivial over a
Zariski open subset of the base. The proof relies upon a relative version of
the contraction theorem.

</DOC>
<DOC>
<DOCNO> 178832 </DOCNO>
Chiral dynamics in few-nucleon systems


  We employ the chiral nucleon-nucleon potential derived using the method of
unitary transformation up to next-to-next-to-leading order (NNLO) to study
bound and scattering states in the two-nucleon system. The predicted partial
wave phase shifts and mixing parameters for higher energies and higher angular
momenta beyond the ones which are fitted are mostly well described for energies
below 300 MeV. Various deuteron properties are discussed. We also apply the
next-to-leading order (NLO) potential to 3N and 4N systems. The resulting 3N
and 4N binding energies are in the same range what is found using standard NN
potentials. Experimental low-energy 3N scattering observables are also very
well reproduced like for standard NN forces. Surprisingly the long standing
Ay-puzzle is resolved at NLO. The cut-off dependence of the scattering
observables is rather mild.

</DOC>
<DOC>
<DOCNO> 121251 </DOCNO>
Estimating Supermassive Black Hole Mass Through Radio/X-Ray Luminosity


  It has been suggested that optically thin and geometrically thick accretion
flows are responsible for the observed radio/X-ray luminosity relation of the
X-ray bright galactic nuclei. If this is the case then central supermassive
black hole masses can be estimated directly from measurements of the core radio
luminosity and the X-ray luminosity, provided that properties of such accretion
flows are known. Calculated ratios of the luminosities are presented in cases
of the standard ADAF model and modified ADAF models, in which a truncation of
inner parts of the flows and winds causing a reduction of the infalling matter
are included. We compare the observed ratio of the luminosities with
predictions from models of optically thin accretion flows. We also discuss the
possible effects of the convection in ADAFs. We confirm that the supermassive
black hole (SMBH) mass estimate is possible with the radio/X-ray luminosity
relation due to ADAF models in the absence of a radio jet. We find that
observational data are insufficient to distinguish the standard ADAF model from
its modified models. However, the ADAF model with convection is inconsistent
with observations, unless microphysics parameters are to be substantially
changed. High resolution radio observations are required to avoid the
contamination of other components, such as, a jet component. Otherwise, the
SMBH mass is inclined to be over-estimated.

</DOC>
<DOC>
<DOCNO> 80888 </DOCNO>
Residual Chiral Symmetry Breaking in Domain-Wall Fermions


  We study the effective quark mass induced by the finite separation of the
domain walls in the domain-wall formulation of chiral fermion as the function
of the size of the fifth dimension ($L_s$), the gauge coupling ($\beta$) and
the physical volume ($V$). We measure the mass by calculating the small
eigenvalues of the hermitian domain-wall Dirac operator ($H_{\rm
DWF}(m_0=1.8))$ in the topologically-nontrivial quenched SU(3) gauge
configurations. We find that the induced quark mass is nearly independent of
the physical volume, decays exponentially as a function of $L_s$, and has a
strong dependence on the size of quantum fluctuations controlled by $\beta$.
The effect of the choice of the lattice gluon action is also studied.

</DOC>
<DOC>
<DOCNO> 40355 </DOCNO>
Neutrino physics and astrophysics with the MACRO detector


  After a brief presentation of the MACRO detector we discuss the data on
atmospheric neutrinos and neutrino oscillations, on high energy (E> 1 GeV)
neutrino astronomy, on indirect searches for WIMPs and low energy (E >7 MeV)
stellar collapse neutrinos.

</DOC>
<DOC>
<DOCNO> 12490 </DOCNO>
Electron transport in Coulomb- and tunnel-coupled one-dimensional


  We develop a linear theory of electron transport for a system of two
identical quantum wires in a wide range of the wire length L, unifying both the
ballistic and diffusive transport regimes. The microscopic model, involving the
interaction of electrons with each other and with bulk acoustical phonons
allows a reduction of the quantum kinetic equation to a set of coupled
equations for the local chemical potentials for forward- and backward-moving
electrons in the wires. As an application of the general solution of these
equations, we consider different kinds of electrical contacts to the
double-wire system and calculate the direct resistance, the transresistance, in
the presence of tunneling and Coulomb drag, and the tunneling resistance. If L
is smaller than the backscattering length l_P, both the tunneling and the drag
lead to a negative transresistance, while in the diffusive regime (L >>l_P) the
tunneling opposes the drag and leads to a positive transresistance. If L is
smaller than the phase-breaking length, the tunneling leads to interference
oscillations of the resistances that are damped exponentially with L.

</DOC>
<DOC>
<DOCNO> 151341 </DOCNO>
Functional Differential Equations for the Free Energy and the Effective


  Extending recent work on QED and the symmetric phase of the euclidean
multicomponent scalar \phi^4-theory, we construct the vacuum diagrams of the
free energy and the effective energy in the ordered phase of \phi^4-theory. By
regarding them as functionals of the free correlation function and the
interaction vertices, we graphically solve nonlinear functional differential
equations, obtaining loop by loop all connected and one-particle irreducible
vacuum diagrams with their proper weights.

</DOC>
<DOC>
<DOCNO> 122838 </DOCNO>
The star-formation history of the universe - an infrared perspective


  A simple and versatile parameterized approach to the star formation history
allows a quantitative investigation of the constraints from far infrared and
submillimetre counts and background intensity measurements.
  The models include four spectral components: infrared cirrus (emission from
interstellar dust), an M82-like starburst, an Arp220-like starburst and an AGN
dust torus. The 60 $\mu$m luminosity function is determined for each chosen
rate of evolution using the PSCz redshift data for 15000 galaxies. The
proportions of each spectral type as a function of 60 $\mu$m luminosity are
chosen for consistency with IRAS and SCUBA colour-luminosity relations, and
with the fraction of AGN as a function of luminosity found in 12 $\mu$m
samples. The luminosity function for each component at any wavelength can then
be calculated from the assumed spectral energy distributions. With assumptions
about the optical seds corresponding to each component and, for the AGN
component, the optical and near infrared counts can be accurately modelled.
  A good fit to the observed counts at 0.44, 2.2, 15, 60, 90, 175 and 850
$\mu$m can be found with pure luminosity evolution in all 3 cosmological models
investigated: $\Omega_o$ = 1, $\Omega_o$ = 0.3 ($\Lambda$ = 0), and $\Omega_o$
= 0.3, $\Lambda$ = 0.7.
  All 3 models also give an acceptable fit to the integrated background
spectrum. Selected predictions of the models, for example redshift
distributions for each component at selected wavelengths and fluxes, are shown.
  The total mass-density of stars generated is consistent with that observed,
in all 3 cosmological models.

</DOC>
<DOC>
<DOCNO> 13830 </DOCNO>
Universality of monopole mode and time evolution of a d-dimensional


  We study a generalised Gross-Pitaevskii equation describing a d-dimensional
harmonic trapped (with trap frequency $\omega_{0}$) weakly interacting Bose gas
with a non-linearity of order (2 k + 1) and scaling exponent (n) of the
interaction potential. Using the time-dependent variational analysis, we
explicitly show that for a particular combination of n, k and d, the
generalised GP equation has the universal monopole oscillation frequency $2
\omega_{0}$. We also find that the time-evolution of the width can be described
universally by the same Hill's equation if the system satisfy that particular
combination. We also obtain the condition for the exact self-similar solutions
of the Gross-Pitaevskii equation. As an application, we discuss low dimensional
trapped Bose condensate state and Calogero model.

</DOC>
<DOC>
<DOCNO> 102820 </DOCNO>
The volume of hyperbolic alternating link complements


  If a hyperbolic link has a prime alternating diagram D, then we show that the
link complement's volume can be estimated directly from D. We define a very
elementary invariant of the diagram D, its twist number t(D), and show that the
volume lies between v_3(t(D) - 2)/2 and v_3(16t(D) - 16), where v_3 is the
volume of a regular hyperbolic ideal 3-simplex. As a consequence, the set of
all hyperbolic alternating and augmented alternating link complements is a
closed subset of the space of all complete finite volume hyperbolic
3-manifolds, in the geometric topology.

</DOC>
<DOC>
<DOCNO> 12683 </DOCNO>
Superconductivity in Ropes of Single-Walled Carbon Nanotubes


  We report measurements on ropes of Single Walled Carbon Nanotubes (SWNT) in
low-resistance contact to non-superconducting (normal) metallic pads, at low
voltage and at temperatures down to 70 mK. In one sample, we find a two order
of magnitude resistance drop below 0.55 K, which is destroyed by a magnetic
field of the order of 1T, or by a d.c. current greater than 2.5 microA. These
features strongly suggest the existence of superconductivity in ropes of SWNT.

</DOC>
<DOC>
<DOCNO> 102407 </DOCNO>
Netted Binomial Matrices


  In this paper we prove that a matrix property of nettedness (all 2x2 cells
satisfy a recurrence) is preserved for powers of such a matrix, where the
coefficients are all instances of the same sequence. Also, we find an
n-dimensional analog of the Q-matrix for the general Pell(Fibonacci) sequence.
We close by giving a conjecture about the spectral properties of the binomial
matrix we found.

</DOC>
<DOC>
<DOCNO> 150444 </DOCNO>
Open strings, simple currents and fixed points


  Some applications of simple current techniques and fixed point resolution to
theories of open strings are discussed. In addition to a brief review of work
presented in two recent papers with L. Huiszoon and N. Sousa, some new results
concerning uniqueness of crosscap coefficients are presented, as well as a
strange sum rule for the modular matrix implied by the existence of crosscaps.

</DOC>
<DOC>
<DOCNO> 8611 </DOCNO>
Silence of magnetic layers to magnetoresistive process and electronic


  A closer look at the temperature (T) dependence of magnetoresistance (MR) of
two polycrystalline magnetic compounds, LaMn$_2$Ge$_2$ and SmMn$_2$Ge$_2$,
previously reported by us, is made. A common feature for both these compounds
is that the low temperature MR is positive (say, below, 30 K) in spite of the
fact that both are ferromagnetic at such low temperatures; in addition, MR as a
function of magnetic field (H) does not track magnetization (M) in the sense
that M saturates at low fields, while MR varies linearly with H. These
observations suggest that the magnetic layers interestingly do not dominate low
temperature magnetotransport process. Interestingly enough, as the T is
increased, say around 100 K, these magnetic layers dominate MR process as
evidenced by the tracking of M and MR in SmMn$_2$Ge$_2$. These results tempts
us to propose that there is an unusual "electronic separation" for MR process
as the T is lowered in this class of compounds.

</DOC>
<DOC>
<DOCNO> 11481 </DOCNO>
Power, Levy, Exponential and Gaussian Regimes in Autocatalytic Financial


  We study by theoretical analysis and by direct numerical simulation the
dynamics of a wide class of asynchronous stochastic systems composed of many
autocatalytic degrees of freedom. We describe the generic emergence of
truncated power laws in the size distribution of their individual elements. The
exponents $\alpha$ of these power laws are time independent and depend only on
the way the elements with very small values are treated. These truncated power
laws determine the collective time evolution of the system. In particular the
global stochastic fluctuations of the system differ from the normal Gaussian
noise according to the time and size scales at which these fluctuations are
considered. We describe the ranges in which these fluctuations are
parameterized respectively by: the Levy regime $\alpha < 2$, the power law
decay with large exponent ($\alpha > 2$), and the exponential decay. Finally we
relate these results to the large exponent power laws found in the actual
behavior of the stock markets and to the exponential cut-off detected in
certain recent measurement.

</DOC>
<DOC>
<DOCNO> 118303 </DOCNO>
Coherent neutrino radiation in supernovae at two loops


  We develop a neutrino transport theory, in terms of the real-time
non-equilibrium Green's functions, which is applicable to physical conditions
arbitrary far from thermal equilibrium. We compute the coherent neutrino
radiation in cores of supernovae by evaluating the two-particle-two-hole
(2p-2h) polarization function with dressed propagators. The propagator dressing
is carried out in the particle-particle channel to all orders in the
interaction. We show that at two loops there are two distinct sources of
coherence effects in the bremsstrahlung. One is the generically off-shell
intermediate state propagation, which leads to the Landau-Pomeranchuk-Migdal
type suppression of radiation. We extend previous perturbative results,
obtained in the leading order in quasiparticle width, by deriving the exact
non-perturbative expression. A new contribution due to off-shell finial/initial
baryon states is treated in the leading order in the quasiparticle width. The
latter contribution corresponds to processes of higher order than second order
in the virial expansion in the number of quasiparticles. At 2p-2h level, the
time component of the polarization tensor for the vector transitions vanishes
identically in the soft neutrino limit. Vector current thereby is conserved.
The contraction of the neutral axial vector current with tensor interaction
among the baryons leads to a non-vanishing contribution to the bremsstrahlung
rate. These rates are evaluated numerically for finite temperature pure neutron
matter at and above the nuclear saturation density.

</DOC>
<DOC>
<DOCNO> 150388 </DOCNO>
On the classical connection between the WZWN model and topological gauge


  It is shown, at the level of the classical action, that the
Wess-Zumino-Witten-Novikov model is equivalent to a combined BF theory and a
Chern-Simons action in the presence of a unique boundary term. This connection
relies on the techniques of non-Abelian T-duality in non-linear sigma models.
We derive some consistency conditions whose various solutions lead to different
dual theories. Particular attention is paid to the cases of the Lie algebras
SO(2,1) and SO(2,1)*SO(2,1). These are shown to yield three dimensional gravity
only if the BF term is ignored.

</DOC>
<DOC>
<DOCNO> 150703 </DOCNO>
Renormalization Group Flows from Gravity in Anti-de Sitter Space versus


  Black hole no-hair theorems are proven using inequalities that govern the
radial dependence of spherically symmetric configurations of matter fields. In
this paper, we analyze the analogous inequalities for geometries dual to
renormalization group flows via the AdS/CFT correspondence. These inequalities
give much useful information about the qualitative properties of such flows.
For Poincare invariant flows, we show that generic flows of relevant or
irrelevant operators lead to singular geometries. For the case of irrelevant
operators, this leads to an apparent conflict with Polchinski's decoupling
theorem, and we offer two possible resolutions to this problem.

</DOC>
<DOC>
<DOCNO> 101336 </DOCNO>
Asymptotic behavior of Patil's approximants in Hardy spaces : The real


  In this paper we consider a robust identification problem for a linear
dynamical control system with limited-frequency intervals. In mathematical
terms, this is the problem of recovering functions in Hardy spaces. Our purpose
is to bound Patil's approximants in the upper half plane case, out of a bounded
real interval $I$. To this end, we deal with residu techniques and give a class
of functions to provide boundedness of these approximants on the complement of
this interval.

</DOC>
<DOC>
<DOCNO> 116555 </DOCNO>
Magnetic Fractal Dimensionality of the Dielectric Breakdown Under Strong


  The formation of breakdown pattern on an insulating surface under the
influence of a transverse magnetic field is theoretically investigated. We have
generalized the Dielectric Breakdown Model (DBM) for the case of external
magnetic field. Concept of the Magnetic Fractal Dimensionality (MFD) is
introduced and its universality is demonstrated. It is shown that MFD saturates
with magnetic fields. The magnetic field dependence of the streamer curvature
is obtained. It is conjectured that nonlinear current interaction is
responsible for the experimentally observed 'spider-legs' like streamer
patterns.

</DOC>
<DOC>
<DOCNO> 151963 </DOCNO>
Canonical approach to 2D induced gravity


  Using canonical method the Liouville theory has been obtained as a
gravitational Wess-Zumino action of the Polyakov string. From this approach it
is clear that the form of the Liouville action is the consequence of the
bosonic representation of the Virasoro algebra, and that the coefficient in
front of the action is proportional to the central charge and measures the
quantum braking of the classical symmetry.

</DOC>
<DOC>
<DOCNO> 122094 </DOCNO>
Viscous Transonic Decretion in Disks of Be Stars


  We study the characteristics of the outflow in disks of Be stars, based on
the viscous decretion disk scenario. In this scenario, the matter ejected from
the equatorial surface of the star drifts outward because of the effect of
viscosity, and forms the disk. For simplicity, we adopt the alpha-prescription
for the viscous stress, and assume the disk to be isothermal. Solving the
resulting wind equations, we find that a transonic solution exists for any
value of alpha. The sonic point is located at r>100R for plausible values of
parameters, where R is the stellar radius. The sonic radius is smaller for
higher temperature and/or larger radiative force. We also find that the
topology of the sonic point is nodal for alpha>0.95, while it is of saddle type
for alpha<0.9. We expect that the sonic point in the former case is unstable,
whereas that in the latter case is stable. The outflow is highly subsonic in
the inner part of the disk. Roughly, the outflow velocity increases linearly
with r and the surface density decreases as r^{-2}. Interestingly, the disk is
near Keplerian in the inner subsonic region, while it is angular momentum
conserving in the outer subsonic region and in the supersonic region. Our
results, together with the observed range of the base density for Be star
disks, suggest that the mass loss rate in the equatorial region is at most
comparable with that in the polar region.

</DOC>
<DOC>
<DOCNO> 116887 </DOCNO>
Automated Operation of the APS LINAC using the Procedure Execution


  The Advanced Photon Source (APS) linear accelerator has two thermionic
cathode rf guns and one photocathode rf gun. The thermionic guns are used
primarily for APS operations while the photocathode gun is used as a
free-electron laser (FEL) driver. With each gun requiring a different lattice
and timing configuration, the need to change quickly between guns puts great
demands on the accelerator operators. Using the Procedure Execution Manager
(PEM), a software environment for managing automated procedures, we have made
start-up and switch-over of the linac systems both easier and more reliable.
The PEM is a graphical user interface written in Tcl/Tk that permits the user
to invoke "machine procedures" and control their execution. It allows
construction of procedures in a hierarchical, parallel fashion, which makes for
efficient execution and development. In this paper, we discuss the features and
advantages of the PEM environment as well the specifics of our procedures for
the APS linac.

</DOC>
<DOC>
<DOCNO> 68173 </DOCNO>
The Higgs sector of the MSSM in the decoupling limit


  We study the heavy Higgs sector of the MSSM composed of the H^\pm, H^0 and
A^0 particles in the so-called decoupling limit where m_{A^0} >> m_Z. By
integrating out these heavy Higgs particles to one-loop, we compute the
effective action for the electroweak gauge bosons and find out that, in the
decoupling limit, all the heavy Higgs effects can be absorbed into
redefinitions of the Standard Model electroweak parameters. This demonstrates
explicitely that the decoupling theorem works for the heavy MSSM Higgs
particles. This is also compared with the paradigmatic and different case of
the Standard Model heavy Higgs particle. Finally, this work together with our
two previous works, complete the demonstration that all the non-standard
particles in the MSSM, namely, squarks, sleptons, charginos, neutralinos and
the heavy Higgs particles, decouple to one-loop from the low energy electroweak
gauge boson physics.

</DOC>
<DOC>
<DOCNO> 152186 </DOCNO>
Generalized Gauge Theories and Weinberg-Salam Model with Dirac-K\"ahler


  We extend previously proposed generalized gauge theory formulation of
Chern-Simons type and topological Yang-Mills type actions into Yang-Mills type
actions. We formulate gauge fields and Dirac-K\"ahler matter fermions by all
degrees of differential forms. The simplest version of the model which includes
only zero and one form gauge fields accommodated with the graded Lie algebra of
$SU(2|1)$ supergroup leads Weinberg-Salam model. Thus the Weinberg-Salam model
formulated by noncommutative geometry is a particular example of the present
formulation.

</DOC>
<DOC>
<DOCNO> 70337 </DOCNO>
Thermal Dileptons from Quark and Hadron Phases of an Expanding Fireball


  A fireball model with time evolution based on transport calculations is used
to examine the dilepton emission rate of an ultra-relativistic heavy-ion
collision. We assume a transition from hadronic matter to a quark-gluon plasma
at a critical temperature T_C between 130-170 MeV. We include thermal
corrections to the hadronic spectra below T_C and use perturbation theory above
T_C. The sensitivity of the spectra with respect to the freeze-out temperature,
the initial fireball temperature and the critical temperature is investigated.

</DOC>
<DOC>
<DOCNO> 85184 </DOCNO>
Planck Scale Physics of the Single Particle Schr\"{o}dinger Equation


  We consider the modification of a single particle Schr\"{o}dinger equation by
the inclusion of an additional gravitational self-potential term which follows
from the prescription that the' mass-density'that enters this term is given by
$m |\psi (\vec {r},t)|^2$, where $\psi (\vec {r}, t)$ is the wavefunction and
$m$ is the mass of the particle. This leads to a nonlinear equation, the '
Newton Schrodinger' equation, which has been found to possess stationary
self-bound solutions, whose energy can be determined exactly using an
asymptotic method. We find that such a particle strongly violates superposition
and becomes a black hole as its mass approaches the Planck mass.

</DOC>
<DOC>
<DOCNO> 70167 </DOCNO>
Graphical Representation of CP Violation Effects in Neutrinoless Double


  We illustrate the graphical method that gives the constraints on the
parameters appearing in the neutrino oscillation experiments and the
neutrinoless double beta decay. This method is applicable in three and four
generations. Though this method is valid for more general case, we examine
explicitly the cases in which the CP violating factors take $\pm 1$ or $\pm i$
in the neutrinoless double beta decay for illustrative clearance. We also
discuss some mass matrix models which lead to the above CP violating factors.

</DOC>
<DOC>
<DOCNO> 100870 </DOCNO>
On the Eisenstein symbol


  The main purpose of this paper is the geometric construction, and the
analysis of the formalism of elliptic Bloch groups. In the setting of absolute
cohomology, we obtain a generalization of Beilinson's Eisenstein symbol to
divisors of an elliptic curve, whose support is not necessarily torsion. For
motivic cohomology, such a generalization is obtained in low degrees. Our main
result shows that the Eisenstein symbol can be defined in all degrees if the
elliptic analogue of the Beilinson-Soule vanishing conjecture holds.

</DOC>
<DOC>
<DOCNO> 10733 </DOCNO>
Topological effects at short antiferromagnetic Heisenberg chains


  The manifestations of topological effects in finite antiferromagnetic
Heisenberg chains is examined by density matrix renormalization group technique
in this paper. We find that difference between integer and half-integer spin
chains shows up in ground state energy per site when length of spin chain is
longer than $\sim\xi$, where $\xi\sim\exp(\pi S)$ is a spin-spin correlation
length, for spin magnitude S up to 5/2. For open chains with spin magnitudes
$S=5/2$ to S=5, we verify that end states with fractional spin quantum numbers
$S'$ exist and are visible even when the chain length is much smaller than the
correlation length $\xi$. The end states manifest themselves in the structure
of the low energy excitation spectrum.

</DOC>
<DOC>
<DOCNO> 13506 </DOCNO>
From Completely Positive Maps to the Quantum Markovian Semigroup Master


  A central problem in the theory of the dynamics of open quantum systems is
the derivation of a rigorous and computationally tractable master equation for
the reduced system density matrix. Most generally, the evolution of an open
quantum system is described by a completely positive linear map. We show how to
derive a completely positive Markovian master equation (the Lindblad equation)
from such a map by a coarse graining procedure. We provide a novel and explicit
recipe for calculating the coefficients of the master equation, using
perturbation theory in the weak-coupling limit. The only parameter external to
our theory is the coarse-graining time-scale. We illustrate the method by
explicitly deriving the master equation for the spin-boson model. The results
are evaluated for the exactly solvable case of pure dephasing, and an excellent
agreement is found within the timescale where the Markovian approximation is
expected to be valid. The method can be extended in principle to include
non-Markovian effects.

</DOC>
<DOC>
<DOCNO> 7622 </DOCNO>
Doppler shift on local density of states and local impurity scattering


  The vortex state thermal and transport properties of the high T_c copper
oxides can be understood in a d-wave gap model and are dominated by the
extended quasiparticle states that exist along the nodal directions in momentum
space. The Doppler shift on these states due to the circulating supercurrents
around the vortex core, introduces new van Hove ridges into the energy
dependent local density of states (LDOS) as a function of distance in the
region between cores. We emphasize the topology of these ridges and the effect
on them of local impurity scattering in Born and unitary limit. We treat
possible orthorhombicity. Effective local scttering rates are also obtaines.

</DOC>
<DOC>
<DOCNO> 13572 </DOCNO>
A Mechanism for Ferrimagnetism and Incommensurability in One-Dimensional


  A mechanism for ferrimagnetism in
 (1+1)-dimensions is discussed. The ferrimagnetism is cased by interactions
described by operators with non-zero conformal spin. Such interactions appear
in such problems as the problem of tunneling between Luttinger liquids and the
problem of frustrated spin ladder. I present exact solutions for a
representative class of models containing such interactions together with a
simple mean field analysis. It is shown that the interactions (i) dynamically
generate static oscillations with a wave vector dependent on the coupling
constant, (ii) give rise to a finite magnetic moment at $T = 0$ accompanied by
the soft mode with a non-relativistic ({\it ferromagnetic}) dispersion $E \sim
k^2$, (iii) generate massive (roton) modes.

</DOC>
<DOC>
<DOCNO> 70523 </DOCNO>
Lepton Asymmetry of the Universe and Charged Quark-Gluon Plasma


  The lepton asymmetry of order one is not excluded experimentally and, if
present, can lead to interesting phenomena in the early Universe. It is shown
that, when the temperature is above the quark-hadron transition, the lepton
asymmetry induces chemical potentials for electric charge and for baryon
number, and makes the quark-gluon plasma electrically charged.

</DOC>
<DOC>
<DOCNO> 85530 </DOCNO>
Integrability conditions for vacuum spacetimes with a Killing vector


  We present a new approach to the study of vacuum spacetimes with a Killing
symmetry. The central quantity in this approach is the exterior derivative of
the Killing vector field, which is a test electromagnetic field. Considering
the algebraic structure of this quantity we get a new view of the integrability
conditions, which provides a natural way of studying the connections between
the algebraic structure of the spacetime and properties of the Killing
symmetry.

</DOC>
<DOC>
<DOCNO> 9801 </DOCNO>
The influence of the crystal lattice on coarsening in unstable epitaxial


  We report the results of computer simulations of epitaxial growth in the
presence of a large Schwoebel barrier on different crystal surfaces: simple
cubic(001), bcc(001), simple hexagonal(001) and hcp(001). We find, that mounds
coarse by a step edge diffusion driven process, if adatoms can diffuse
relatively far along step edges without being hindered by kink-edge diffusion
barriers. This yields the scaling exponents alpha = 1, beta = 1/3. These
exponents are independent of the symmetry of the crystal surface. The crystal
lattice, however, has strong effects on the morphology of the mounds, which are
by no means restricted to trivial symmetry effects: while we observe pyramidal
shapes on the simple lattices, on bcc and hcp there are two fundamentally
different classes of mounds, which are encompanied by characteristic diffusion
currents: a metastable one with rounded corners, and an actively coarsening
configuration, which breaks the symmetry given by the crystal surface.

</DOC>
<DOC>
<DOCNO> 7641 </DOCNO>
Phase ordering at the lambda transition in liquid 4-He


  A modified ideal Bose gas model is proposed as an approach for liquid helium
at the lambda point. The decisive modification of the ideal Bose gas model is
the use of phase ordered single particle functions. The entropy due to this
phase ordering is calculated. Its statistical expectation value yields a
logarithmic singularity of the specific heat.

</DOC>
<DOC>
<DOCNO> 40069 </DOCNO>
MSSM SUSY Searches at LEP2


  The status of SUSY searches at LEP2 up to centre-of-mass energy of 202 GeV is
presented. Search strategies for sleptons, squarks, charginos and neutralinos
are discussed in the framework of Minimal Supersymmetric Standard Model with
R-parity conservation. With no indication for the production of these particles
new limits are set on their masses.

</DOC>
<DOC>
<DOCNO> 85062 </DOCNO>
Gravitational Wave Chirp Search: Economization of PN Matched Filter Bank


  The final inspiral phase in the evolution of a compact binary consisting of
black holes and/or neutron stars is among the most probable events that a
network of ground-based interferometric gravitational wave detectors is likely
to observe. Gravitational radiation emitted during this phase will have to be
dug out of noise by matched-filtering (correlating) the detector output with a
bank of several $10^5$ templates, making the computational resources required
quite demanding, though not formidable. We propose an interpolation method for
evaluating the correlation between template waveforms and the detector output
and show that the method is effective in substantially reducing the number of
templates required. Indeed, the number of templates needed could be a factor
$\sim 4$ smaller than required by the usual approach, when the minimal overlap
between the template bank and an arbitrary signal (the so-called {\it minimal
match}) is 0.97. The method is amenable to easy implementation, and the various
detector projects might benefit by adopting it to reduce the computational
costs of inspiraling neutron star and black hole binary search.

</DOC>
<DOC>
<DOCNO> 68749 </DOCNO>
The Superpartner Spectrum of Gaugino Mediation


  We compute the superpartner masses in a class of models with gaugino
mediation (or no-scale) boundary conditions at a scale between the GUT and
Planck scales. These models are compelling because they are simple, solve the
supersymmetric flavor and CP problems, satisfy all constraints from colliders
and cosmology, and predict the superpartner masses in terms of very few
parameters. Our analysis includes the renormalization group evolution of the
soft-breaking terms above the GUT scale. We show that the running above the GUT
scale is largely model independent and find that a phenomenologically viable
spectrum is obtained.

</DOC>
<DOC>
<DOCNO> 13276 </DOCNO>
Computer Simulations for Biological Ageing and Sexual Reproduction


  The sexual version of the Penna model of biological ageing, simulated since
1996, is compared here with alternative forms of reproduction as well as with
models not involving ageing. In particular we want to check how sexual forms of
life could have evolved and won over earlier asexual forms hundreds of million
years ago. This computer model is based on the mutation-accumulation theory of
ageing, using bits-strings to represent the genome. Its population dynamics is
studied by Monte Carlo methods.

</DOC>
<DOC>
<DOCNO> 13923 </DOCNO>
Alternating-Spin Ladders in a Magnetic Field: New Magnetization Plateaux


  We study numerically the formation of magnetization plateaux with the Lanczos
method in 2-leg ladders with mixed spins of magnitudes $(S_1,S_2)=(1,1/2)$
located at alternating positions along the ladder and with dimerization
$\gamma$. For interchain coupling $J'>0$ and $\gamma=0$, we find normalized
plateaux at $m=1/3$ starting at zero field and $m=1$ (saturation), while when
$\gamma \ne 0$ is columnar, another extra plateau at $m=2/3$ shows up. For
$J'<0$, when $\gamma<\gamma_c(J')$ we find no plateau while for
$\gamma>\gamma_c(J')$ we find four plateaux at $m=0,1/3,2/3,1$. We also apply
several approximate analytical methods (Spin Wave Theory, Low-Energy Effective
Hamiltonians and Bosonization) to understand these findings and to conjeture
the behaviour of ferrimagnetic ladders with a bigger number of legs.

</DOC>
<DOC>
<DOCNO> 150549 </DOCNO>
Nonuniqueness of the $\lambda\Phi^4$-vacuum


  We prove that the massless neutral $\lambda\Phi^4$-theory does not possess a
unique vacuum. Based on the Wightman axioms the non-existence of a state which
preserves Poincar{\'e} and scale invariance is demonstrated non-perturbatively
for a non-vanishing self-interaction. We conclude that it is necessary to break
the scale invariance in order to define a vacuum state. The renormalized vacuum
expectation value of the energy-momentum tensor is derived from the two-point
Wightman function employing the point-splitting technique and its relation to
the phionic and the scalar condensate is addressed. Possible implications to
other self-interacting field theories and to different approaches in quantum
field theory are pointed out. PACS: 11.10.Cd, 11.15.Tk, 11.30.Qc

</DOC>
<DOC>
<DOCNO> 152560 </DOCNO>
On the evaluation of the evolution operator Z_Reg(R_2,R_1) in the


  We evaluate the evolution operator Z_Reg(R_2,R_1) introduced by Diakonov and
Petrov for the definition of the Wilson loop in terms of a path integral over
gauge degrees of freedom. We use the procedure suggested by Diakonov and Petrov
(Phys. Lett. B224 (1989) 131) and show that the evolution operator vanishes.

</DOC>
<DOC>
<DOCNO> 100017 </DOCNO>
Factorization of Combinatorial R matrices and Associated Cellular


  Solvable vertex models in statistical mechanics give rise to soliton cellular
automata at q=0 in a ferromagnetic regime. By means of the crystal base theory
we study a class of such automata associated with non-exceptional quantum
affine algebras U'_q(\hat{\geh}_n). Let B_l be the crystal of the
U'_q(\hat{\geh}_n)-module corresponding to the l-fold symmetric fusion of the
vector representation. For any crystal of the form B = B_{l_1} \otimes ...
\otimes B_{l_N}, we prove that the combinatorial R matrix B_M \otimes B
\xrightarrow{\sim} B \otimes B_M is factorized into a product of Weyl group
operators in a certain domain if M is sufficiently large. It implies the
factorization of certain transfer matrix at q=0, hence the time evolution in
the associated cellular automata. The result generalizes the ball-moving
algorithm in the box-ball systems.

</DOC>
<DOC>
<DOCNO> 101777 </DOCNO>
Descent-cycling in Schubert calculus


  We prove two lemmata about Schubert calculus on generalized flag manifolds
G/B, and in the case of the ordinary flag manifold GL_n/B we interpret them
combinatorially in terms of descents, and geometrically in terms of missing
subspaces. One of them gives a symmetry of Schubert calculus that we
christen_descent-cycling_. Computer experiment shows that these lemmata suffice
to determine all of GL_n Schubert calculus through n=5, and 99.97%+ at n=6. We
use them to give a quick proof of Monk's rule. The lemmata also hold in
equivariant (``double'') Schubert calculus for Kac-Moody groups G.

</DOC>
<DOC>
<DOCNO> 84570 </DOCNO>
Closed cosmologies with a perfect fluid and a scalar field


  Closed, spatially homogeneous cosmological models with a perfect fluid and a
scalar field with exponential potential are investigated, using dynamical
systems methods. First, we consider the closed Friedmann-Robertson-Walker
models, discussing the global dynamics in detail. Next, we investigate
Kantowski-Sachs models, for which the future and past attractors are
determined. The global asymptotic behaviour of both the
Friedmann-Robertson-Walker and the Kantowski-Sachs models is that they either
expand from an initial singularity, reach a maximum expansion and thereafter
recollapse to a final singularity (for all values of the potential parameter
kappa), or else they expand forever towards a flat power-law inflationary
solution (when kappa^2<2). As an illustration of the intermediate dynamical
behaviour of the Kantowski-Sachs models, we examine the cases of no barotropic
fluid, and of a massless scalar field in detail. We also briefly discuss
Bianchi type IX models.

</DOC>
<DOC>
<DOCNO> 8843 </DOCNO>
Implementation of the Projector Augmented Wave LDA+U Method: Application


  The so-called local density approximation plus the multi-orbital mean-field
Hubbard model (LDA+U) has been implemented within the all-electron projector
augmented-wave method (PAW), and then used to compute the insulating
antiferromagnetic ground state of NiO and its optical properties. The
electronic and optical properties have been investigated as a function of the
Coulomb repulsion parameter U. We find that the value obtained from constrained
LDA (U=8 eV) is not the best possible choice, whereas an intermediate value
(U=5 eV) reproduces the experimental magnetic moment and optical properties
satisfactorily. At intermediate U, the nature of the band gap is a mixture of
charge transfer and Mott-Hubbard type, and becomes almost purely of the
charge-transfer type at higher values of U. This is due to the enhancement of
the oxygen 2p states near the top of the valence states with increasing U
value.

</DOC>
<DOC>
<DOCNO> 122509 </DOCNO>
Stellar Coronae with \textit{XMM-Newton} RGS. I. Coronal Structure


  First results from high-resolution coronal spectroscopy with the {\it
XMM-Newton} Reflection Grating Spectrometers (RGS) are reviewed. Five stellar
systems (HR 1099, Capella, Procyon, YY Gem, AB Dor) have been observed. The
emphasis of the present paper is on overall coronal structure. Elemental
abundances in {\it active stars} are found to be `anomalous' in the sense that
they tend to increase with increasing First Ionization Potential (FIP - i.e.,
signifying an inverse FIP effect). Coronal densities are measured at levels of
a few times $10^{10}$ cm$^{-3}$ for cooler plasma, although there are
indications for very high densities in the hotter plasma components.

</DOC>
<DOC>
<DOCNO> 119274 </DOCNO>
Observations of Type I Bursts from Neutron Stars


  Observations of Type I X-ray bursts have long been taken as evidence that the
sources are neutron stars. Black body models approximate the spectral data and
imply a suddenly heated neutron star cooling over characteristic times of
seconds to minutes. The phenomena are convincingly explained in terms of
nuclear burning of accreted gas on neutron stars with low mass companion stars.
Prospects are promising that detailed theory and data from RXTE and future
missions will lead to better determinations of important physical parameters
(neutron star mass and radius, composition of the accreting gas, distance of
the source). Among the variety of bursts observed, there are probably
representatives of different kinds of explosive burning. RXTE's discovery of a
2.5 ms persistent coherent period from one Type I burster has now linked
bursters indisputably to the epitome of a neutron star, a fast spinning
magnetic compact object. Oscillations in some bursts had already been thought
to arise from the neutron stars' rotations. Detailed observations of these
oscillations are touchstones of how the explosive bursts originate and
progress, as well as independent measures of the neutron star parameters.

</DOC>
<DOC>
<DOCNO> 7716 </DOCNO>
On the Consistency of the Deterministic Local Volatility Function Model


  We show that the frequent claim that the implied tree prices exotic options
consistently with the market is untrue if the local volatilities are subject to
change and the market is arbitrage-free. In the process, we analyse -- in the
most general context -- the impact of stochastic variables on the P&L of a
hedged portfolio, and we conclude that no model can a priori be expected to
price all exotics in line with the vanilla options market. Calibration of an
assumed underlying process from vanilla options alone must not be overly
restrictive, yet still unique, and relevant to all exotic options of interest.
For the implied tree we show that the calibration to real-world prices allows
us to only price vanilla options themselves correctly. This is usually
attributed to the incompleteness of the market under traditional stochastic
(local) volatility models. We show that some `weakly' stochastic volatility
models without quadratic variation of the volatilities avoid the incompleteness
problems, but they introduce arbitrage. More generally, we find that any
stochastic tradable either has quadratic variation -- and therefore a
$\Ga$-like P&L on instruments with non-linear exposure to that asset -- or it
introduces arbitrage opportunities.

</DOC>
<DOC>
<DOCNO> 39913 </DOCNO>
Energy losses of Q-balls in Matter, Earth and Detectors


  We present a sudy of the interactions of Q-balls with matter, and their
energy losses in the earth, for a large range of velocities. These calculations
are used to computethe fractional geometrical acceptance of underground
detectors. Furthermore we computed the light yield in liquidscintillators, the
ionization in streamer tubes and the Restricted Energy Loss in nuclear track
detectors.

</DOC>
<DOC>
<DOCNO> 69567 </DOCNO>
Monte Carlo Generators and the CCFM Equation


  We discuss three implementations of the CCFM evolution equations in event
generator programs. We find that some of them are able to describe observables
such as forward jet rates in DIS at HERA, but only if the so-called consistency
constraint is removed. We also find that these results are sensitive to the
treatment of non-singular terms in the gluon splitting function.

</DOC>
<DOC>
<DOCNO> 11412 </DOCNO>
High-resolution Compton Scattering as a Probe of Fermiology and Electron


  Compton scattering is one of the few spectroscopies which directly probes the
ground state momentum density in materials. Recent progress in synchrotron
light sources has brought a renewed interest in the technique as a tool for
investigating fermiology related issues on the one hand, and as a unique window
on hitherto inaccessible correlation effects in the electron gas on the other.
We provide an overview of some of our recent work on a variety of metals and
disordered alloys, including Li, $\rm Li_{1-x}Mg_x$, Be, Cu, $\rm
Ni_{75}Cu_{25}$, $\rm Ni_{75}Co_{25}$, Al and Al-Li.

</DOC>
<DOC>
<DOCNO> 116477 </DOCNO>
Exact Topological Twistons in Crystalline Polyethylene


  We investigate the presence of topological twistons in crystalline
polyethylene. We describe crystalline polyethylene with a model that couples
the torsional and longitudinal degrees of freedom of the polymeric chain by
means of a system of two real scalar fields. This model supports topological
twistons, which are described by exact and stable topological solutions that
appear when the interaction between torsional and longitudinal fields is
polynomial, containing up to the sixth power in the fields. We calculate the
energy of the topological twiston, and the result is in very good agreement
with the value obtained via molecular simulation.

</DOC>
<DOC>
<DOCNO> 117581 </DOCNO>
High Resolution Simulation of Galaxy Formation with Feedback


  We present results from a Smoothed Particle Hydrodynamic (SPH) simulation of
galaxy formation that exceeds the minimum resolution requirement suggested by
Steinmetz & Muller (1993) of 3*10^4 SPH particles per galaxy. Using the
multiple mass technique an effective resolution of a little over one billion
particles is attained within a 48 Mpc cube. We find that even with an SPH mass
resolution of 1.5*10^6 solar masses and a plausible feedback algorithm, the
cooling catastrophe continues to be a problem for Einstein-de Sitter CDM
cosmologies. Increasing resolution also appears to exacerbate the core-halo
angular momentum transport problem.

</DOC>
<DOC>
<DOCNO> 71737 </DOCNO>
Tests of Spacetime Symmetry with Particle Traps


  Lorentz and CPT symmetry have been tested at high precision in numerous
experiments. A general theoretical framework incorporating possible Lorentz and
CPT violation in an extension of the standard model of particle physics has
been developed. In this framework, analyses of several precision experiments
have been performed to find unsuppressed symmetry-violating signals. This paper
discusses features of the theory, presents results for trapped-particle
systems, and reports bounds from recent experiments.

</DOC>
<DOC>
<DOCNO> 100160 </DOCNO>
Structure of the Three-dimensional Quantum Euclidean Space


  As an example of a noncommutative space we discuss the quantum 3-dimensional
Euclidean space $R^3_q$ together with its symmetry structure in great detail.
The algebraic structure and the representation theory are clarified and
discrete spectra for the coordinates are found. The q-deformed Legendre
functions play a special role. A completeness relation is derived for these
functions.

</DOC>
<DOC>
<DOCNO> 117554 </DOCNO>
Modeling the X-ray - UV Correlations in NGC 7469


  We model the correlated X-ray - UV observations of NGC 7469, for which well
sampled data in both these bands have been obtained recently in a
multiwavelength monitoring campaign. To this end we derive the transfer
function in wavelength \ls and time lag \t, for reprocessing hard (X-ray)
photons from a point source to softer ones (UV-optical) by an infinite plane
(representing a cool, thin accretion disk) located at a given distance below
the X-ray source, under the assumption that the X-ray flux is absorbed and
emitted locally by the disk as a black body of temperature appropriate to the
incident flux. Using the observed X-ray light curve as input we have computed
the expected continuum UV emission as a function of time at several wavelengths
(\l \l 1315 \AA, \l \l 6962 \AA, \l \l 15000 \AA, \l \l 30000 \AA) assuming
that the X-ray source is located one \sc radius above the disk plane, with the
mass of the black hole $M$ and the latitude angle $\theta$ of the observer
relative to the disk plane as free parameters. We have searched the parameter
space of black hole masses and observer azimuthal angles but we were unable to
reproduce UV light curves which would resemble, even remotely, those observed.
We also explored whether particular combinations of the values of these
parameters could lead to light curves whose statistical properties (i.e. the
autocorrelation and cross correlation functions) would match those
corresponding to the observed UV light curve at \l \l 1315 \AA. Even though we
considered black hole masses as large as $10^9$ M$_{\odot}$ no such match was
possible. Our results indicate that some of the fundamental assumptions of this
model will have to be modified to obtain even approximate agreement between the
observed and model X-ray - UV light curves.

</DOC>
<DOC>
<DOCNO> 121929 </DOCNO>
Is the LMA solar-neutrino solution ruled out by SN1987A data?


  The development of new supernova neutrino detectors relies on the expected
hard energy spectrum of the nu_mu and nu_tau emitted in the supernova. We show
that SN1987A was sensitive to the large mixing angle (LMA) and "just so"
solution to the solar neutrino problem. We review the previous analysis of the
SN1987A data and propose a new analysis. The results of this analysis strongly
disfavor the LMA solution, provided the nu_mu and nu_tau are hard as predicted

</DOC>
<DOC>
<DOCNO> 99729 </DOCNO>
On Erdos's elementary method in the asymptotic theory of partitions


  Let m be a positive integer, and let A be the set of all positive integers
that belong to a union of r distinct congruence classes modulo m. We assume
that the elements of A are relatively prime, that is, gcd(A) = 1. Let p_A(n)
denote the number of partitions of n into parts belonging to A. We obtain the
asymptotic formula log p_A(n) ~ \pi \sqrt(2rn/3m). The proof is based on
Erdos's elementary method to obtain the asymptotic formula for the usual
partition function p(n).

</DOC>
<DOC>
<DOCNO> 116918 </DOCNO>
Progress on the 140 KV, 10 Megawatt Peak, 1 Megawatt Average Polyphase


  This paper describes electrical design and operational characteristics of a
zero-voltage-switching 20 kHz polyphase bridge, boost converter/modulator for
klystron pulse application. The DC-DC converter derives the buss voltages from
a standard 13.8 kV to 2300 Y substation cast-core transformer. Energy storage
and filtering is provided by self-clearing metallized hazy polypropylene
traction capacitors. Three "H-Bridge" IGBT switching networks are used to
generate the polyphase 20 kHz transformers primary drive waveforms. The 20 kHz
drive waveforms are chirped the appropriate duration to generate the desired
klystron pulse width. PWM (pulse width modulation) of the individual 20 kHz
pulses is utilized to provide regulated output waveforms with adaptive
feedforward and feedback techniques. The boost transformer design utilizes
amorphous nanocrystalline material that provides the required low core loss at
design flux levels and switching frequencies. Resonant shunt peaking is used on
the transformer secondary to boost output voltage and resonate transformer
leakage inductance. With the appropriate transformer leakage inductance and
peaking capacitance, zero-voltage-switching of the IGBT's is attained,
minimizing switching losses. A review of these design parameters and a
comparison of computer calculations, scale model, and first article results
will be performed.

</DOC>
<DOC>
<DOCNO> 100786 </DOCNO>
On the genera of X_0(N)


  Let g_0(N) be the genus of the modular curve X_0(N). We record several
properties of the sequence {g_0(N)}. Even though the average size of g_0(N) is
1.25N/pi^2, a random positive integer has probability zero of being a value of
g_0(N). Also, if N is a random positive integer then g_0(N) is odd with
probability one. The smallest non-negative integer not occuring as g_0(N) for
any N is 150; the smallest such odd integer is 49267.

</DOC>
<DOC>
<DOCNO> 84143 </DOCNO>
Exotic spacetimes, superconducting strings with linear momentum, and


  We derive the general exact vacuum metrics associated with a stationary (non
static), non rotating, cylindrically symmetric source. An analysis of the
geometry described by these vacuum metrics shows that they contain a subfamily
of metrics that, although admitting a consistent time orientation, display
"exotic" properties, such as "trapping" of geodesics and closed causal curves
through every point. The possibility that such spacetimes could be generated by
a superconducting string, endowed with a neutral current and momentum, has
recently been considered by Thatcher and Morgan. Our results, however, differ
from those found by Thatcher and Morgan, and the discrepancy is explained. We
also analyze the general possibility of constructing physical sources for the
exotic metrics, and find that, under certain restrictions, they must always
violate the dominant energy condition (DEC). We illustrate our results by
explicitly analyzing the case of concentric shells, where we find that in all
cases the external vacuum metric is non exotic if the matter in the shells
satisfies the DEC.

</DOC>
<DOC>
<DOCNO> 101042 </DOCNO>
Abelian Unipotent Subgroups of Reductive Groups


  Let G be a connected reductive group defined over an algebraically closed
field k of characteristic p > 0. The purpose of this paper is two-fold. First,
when p is a good prime, we give a new proof of the ``order formula'' of D.
Testerman for unipotent elements in G; moreover, we show that the same formula
determines the p-nilpotence degree of the corresponding nilpotent elements in
the Lie algebra of G.
  Second, if G is semisimple and p is sufficiently large, we show that G always
has a faithful representation (r,V) with the property that the exponential of
dr(X) lies in r(G) for each p-nilpotent X in Lie(G). This property permits a
simplification of the description given by Suslin, Friedlander, and Bendel of
the (even) cohomology ring for the Frobenius kernels G_d, d > 1. The previous
authors already observed that the natural representation of a classical group
has the above property (with no restriction on p). Our methods apply to any
Chevalley group and hence give the result also for quasisimple groups with
``exceptional type'' root systems. The methods give explicit sufficient
conditions on p; for an adjoint semisimple G with Coxeter number h, the
condition p > 2h -2 is always good enough.

</DOC>
<DOC>
<DOCNO> 68702 </DOCNO>
Modal field theory and quasi-sparse eigenvector diagonalization


  We review recent developments in non-perturbative field theory using modal
field methods. We discuss Monte Carlo results as well as a new diagonalization
technique known as the quasi-sparse eigenvector method.

</DOC>
<DOC>
<DOCNO> 80944 </DOCNO>
U(1) Chiral gauge theory on lattice with gauge-fixed domain wall


  We investigate a U(1) lattice chiral gauge theory with domain wall fermions
and gauge fixing. In the reduced model limit, our perturbative and numerical
investigations at Yukawa coupling y=1 show that there are no extra mirror
chiral modes. The longitudinal gauge degrees of freedom have no effect on the
free domain wall fermion spectrum consisting of opposite chiral modes at the
domain wall and the anti-domain wall which have an exponentially damped
overlap. Our numerical investigation at small Yukawa couplings also leads to
similar conclusions as above.

</DOC>
<DOC>
<DOCNO> 68713 </DOCNO>
Nuclear geometry of jet quenching


  The most suitable way to study the jet quenching as a function of distance
traversed is varying the impact parameter b of ultrarelativistic
nucleus-nucleus collision (initial energy density in nuclear overlapping zone
is almost independent of b up to b R_A). It is shown that b-dependences of
medium-induced radiative and collisional energy losses of a hard parton jet
propagating through dense QCD-matter are very different. The experimental
verification of this phenomenon could be performed for a jet with non-zero cone
size basing on essential difference between angular distributions of
collisional and radiative energy losses.

</DOC>
<DOC>
<DOCNO> 11376 </DOCNO>
Absence of the zero bias peak in vortex tunneling spectra of high


  The c-axis tunneling matrix of high-Tc superconductors is shown to depend
strongly on the in-plane momentum of electrons and vanish along the four nodal
lines of the d(x^2-y^2)-wave energy gap. This anisotropic tunneling matrix
suppresses completely the contribution of the most extended quasiparticles in
the vortex core to the c-axis tunneling current and leads to a spectrum similar
to that of a nodeless superconductor. Our results give a natural explanation of
the absence of the zero bias peak as well as other features observed in the
vortex tunneling spectra of high-Tc cuprates.

</DOC>
<DOC>
<DOCNO> 11620 </DOCNO>
Magnetic transition and polaron crossover in a two-site single polaron


  A two-site double exchange model with a single polaron is studied using a
perturbation expansion based on the modified Lang-Firsov transformation. The
antiferromagnetic to ferromagnetic transition and the crossover from small to
large polaron are investigated for different values of the antiferromagnetic
interaction ($J$) between the core spins and the hopping ($t$) of the itinerant
electron. Effect of the external magnetic field on the small to large polaron
crossover and on the polaronic kinetic energy are studied. When the magnetic
transition and the small to large polaron crossover coincide for some suitable
range of $J/t$, the magnetic field has very pronounced effect on the transport.

</DOC>
<DOC>
<DOCNO> 84658 </DOCNO>
Laser interferometer gravitational wave detectors


  I give a brief introduction on gravitational wave laser interferometers,
possible detectable sources from the ground and noise in the detectors

</DOC>
<DOC>
<DOCNO> 121625 </DOCNO>
Maximum Disk Mass Models for Spiral Galaxies


  We present axisymmetric maximum disk mass models for a sample of 74 spiral
galaxies taken from the southern sky Fabry-Perot Tully-Fisher survey (Schommer
et al. 1993). The sample contains galaxies spanning a large range of
morphologies and having rotation widths from 180 km/sec to 680 km/secs. For
each galaxy we have an I-band image and a 2-d H_alpha velocity field. The
distribution of mass is modeled as a sum of disk and bulge components with
distinct, constant mass-to-light ratios. No dark matter halo is included in the
fits. The models reproduce the overall structure of the rotation curves in the
majority of galaxies, providing good fits to galaxies which exhibit pronounced
structural differences in their surface brightness profiles. 75% of galaxies
for which the rotation curve is measured to R_23.5 or beyond are well fit by a
mass-traces-light model for the entire region within R_23.5. The models for
about 20% of the galaxies do not fit well; the failure of most of these models
is traced directly to non-axisymmetric structures, primarily bars but also
strong spiral arms. The median I-band M/L of the disk plus bulge is 2.4+/-0.9
h_75 in solar units, consistent with normal stellar populations. These results
require either that the mass of dark matter within the optical disk of spiral
galaxies is small, or that its distribution is very precisely coupled to the
distribution of luminous matter.

</DOC>
<DOC>
<DOCNO> 151947 </DOCNO>
Supersymmetric Brane World Scenarios from Off-Shell Supergravity


  Using N=2 off-shell supergravity in five dimensions, we supersymmetrize the
brane world scenario of Randall and Sundrum. We extend their construction to
include supersymmetric matter at the fixpoints.

</DOC>
<DOC>
<DOCNO> 178454 </DOCNO>
Inclusive meson production in peripheral collisions of ultrarelativistic


  There exist several proposals to use Weizs\"{a}cker-Williams photons
generated by ultrarelativistic heavy ions to produce exotic particles in
$\gamma\gamma$ fusion reactions. To estimate the background conditions for such
reactions we analyze various mechanisms of meson production in very peripheral
collisions of ultrarelativistic heavy ions at RHIC and LHC energies. Besides
$\gamma\gamma$ fusion they include also electromagnetic $\gamma A$ interactions
and strong nucleon-nucleon interactions in grazing $AA$ collisions. All these
processes are characterised by low multiplicities of produced particles.
$\gamma A$ and $AA$ events are simulated by corresponding Monte Carlo codes,
RELDIS and FRITIOF. In each of these processes a certain fraction of pions is
produced close to the mid-rapidity region that gives a background for the
$\gamma\gamma$ events. The possibility of selecting mesons produced in
$\gamma\gamma$ fusion events via different $p_t$ cut procedures is
demonstrated.

</DOC>
<DOC>
<DOCNO> 119370 </DOCNO>
Ionization physics evidence for magnetic flare origin of X-rays in AGN


  We present full disk X-ray reflection spectra for two currently popular
accretion flow geometries for AGN -- the lamppost model frequently used to
discuss the iron line reverberation in AGN, and the model where the X-rays are
produced in magnetic flares above a cold accretion disk (AD). The lamppost
spectra contain several spectroscopic features characteristic of highly ionized
material that are not seen in the X-ray spectra of most AGN. The magnetic flare
model, on the other hand, produces reflected spectra that are roughly a
super-position of a power-law and a {\em neutral-like} reflection and iron
K$\alpha$ line, and are thus more in line with typical AGN X-ray spectra.
Furthermore, because of the difference in the ionization structure of the
illuminated material in the two models, the line equivalent width increases
with the X-ray luminosity, $L_x$, for the lamppost, and decreases with $L_x$
for the flare model. In light of these theoretical insights, recent iron line
reverberation studies of AGN, the X-ray Baldwin effect, and the general lack of
X-ray reflection features in distant quasars all suggest that, for high
accretion rates, the cold accretion disk is covered by a Thomson thick,
completely ionized skin. Because the latter is only possible when the X-rays
are concentrated to small emitting regions, we believe that this presents a
strong evidence for the magnetic flare origin of X-rays in AGN.

</DOC>
<DOC>
<DOCNO> 118532 </DOCNO>
GADGET: A code for collisionless and gasdynamical cosmological


  We describe the newly written code GADGET which is suitable both for
cosmological simulations of structure formation and for the simulation of
interacting galaxies. GADGET evolves self-gravitating collisionless fluids with
the traditional N-body approach, and a collisional gas by smoothed particle
hydrodynamics. Along with the serial version of the code, we discuss a parallel
version that has been designed to run on massively parallel supercomputers with
distributed memory. While both versions use a tree algorithm to compute
gravitational forces, the serial version of GADGET can optionally employ the
special-purpose hardware GRAPE instead of the tree. Periodic boundary
conditions are supported by means of an Ewald summation technique. The code
uses individual and adaptive timesteps for all particles, and it combines this
with a scheme for dynamic tree updates. Due to its Lagrangian nature, GADGET
thus allows a very large dynamic range to be bridged, both in space and time.
So far, GADGET has been successfully used to run simulations with up to 7.5e7
particles, including cosmological studies of large-scale structure formation,
high-resolution simulations of the formation of clusters of galaxies, as well
as workstation-sized problems of interacting galaxies. In this study, we detail
the numerical algorithms employed, and show various tests of the code. We
publically release both the serial and the massively parallel version of the
code.

</DOC>
<DOC>
<DOCNO> 8390 </DOCNO>
Depinning and dynamic phases in driven three-dimensional vortex lattices


  We use three-dimensional molecular dynamics simulations of magnetically
interacting pancake vortices to study the dynamic phases of vortex lattices in
highly anisotropic materials such as BSCCO. Our model treats the magnetic
interactions of the pancakes exactly, with long-range logarithmic interactions
both within and between planes. The pancake vortices decouple at low drives and
show two-dimensional plastic flow. The vortex lattice both recouples and
reorders as the driving current is increased, eventually forming a recoupled
crystalline-like state at high drives. We construct a phase diagram as a
function of interlayer coupling and show the relationship between the
recoupling transition and the single-layer reordering transitions.

</DOC>
<DOC>
<DOCNO> 11642 </DOCNO>
Identifying the Operator Content, the Homogeneous Sine-Gordon models


  We address the general question of how to reconstruct the field content of a
quantum field theory from a given scattering theory in the context of the form
factor program. For the $SU(3)_2$-homogeneous Sine-Gordon model we construct
systematically all $n$-particle form factors for a huge class of operators in
terms of general determinant formulae. We investigate how different operators
are interrelated by the momentum space cluster property. Finally we compute
several two-point correlation functions and carry out the ultraviolet limit in
order to identify each operator with its corresponding partner in the
underlying conformal field theory.

</DOC>
<DOC>
<DOCNO> 12520 </DOCNO>
Comment on "Cooper instability of composite fermions"


  We comment on the recent paper by Scarola, Park, and Jain [Nature v. 406, p.
863 (2000); cond-mat/0012030] on a trial wavefunction calculation of pairing in
a fractional quantum Hall system at nu=5/2. We point out two errors that
invalidate the claimed calculations of a binding energy for Cooper pairs and of
an energy gap for charged excitations.

</DOC>
<DOC>
<DOCNO> 12134 </DOCNO>
Pressure and Stress Tensor in a Yukawa Fluid


  Systems of particles interacting through a screened Coulomb potential of the
Debye-Yukawa form are considered. The pressure is obtained from the stress
tensor of the field corresponding to the Yukawa interaction, by a suitable
statistical average. This approach is especially appropriate for systems living
in a curved space. In a curved space, a self contribution to the pressure
appears, and it is essential to take it into account for retrieving a correct
pressure when the Yukawa interaction tends to the Coulomb interaction.

</DOC>
<DOC>
<DOCNO> 120127 </DOCNO>
A Self-Consistent Test of Comptonisation Models Using Bepposax


  We test accurate models of Comptonisation spectra over BeppoSAX observations
of Seyfert galaxies focusing on the long look at NGC 5548. The hot plasma
temperature derived with these models is significantly higher than that
obtained fitting the same data with a power law plus high energy cut off model
for the continuum. This is due to the fact that in anisotropic geometries
Comptonisation spectra show "intrinsic" curvature which moves the fitted high
energy cut-off to higher energies. We also show preliminary results of our
analysis of a sample of 5 other Seyfert galaxies.

</DOC>
<DOC>
<DOCNO> 123172 </DOCNO>
Stellar spectroscopy far beyond the Local Group


  Multi-object spectroscopic observations of blue supergiants in NGC 3621, a
spiral galaxy at a distance of 6.7 Mpc, carried out with the ESO VLT and FORS
are presented. We demonstrate the feasibility of quantitative stellar
spectroscopy at distances approaching a ten-fold increase over previous
investigations by determining chemical composition, stellar parameters,
reddening, extinction and wind properties of one of our targets, a supergiant
of spectral type A1 Ia located in the outskirts of NGC 3621. The metallicity
(determined from iron group elements) is reduced by a factor of two relative to
the sun in qualitative agreement with results from previous abundance studies
based on H II region oxygen emission lines. Reddening and extinction are E(B-V)
= 0.12 and Av = 0.37, respectively, mostly caused by the galactic foreground.
Comparing stellar wind momentum and absolute V magnitude with galactic and M31
counterparts we confirm the potential of the wind momentum-luminosity
relationship as an alternative tool to estimate extragalactic distances.

</DOC>
<DOC>
<DOCNO> 10918 </DOCNO>
Metastability and small eigenvalues in Markov chains


  In this letter we announce rigorous results that elucidate the relation
between metastable states and low-lying eigenvalues in Markov chains in a much
more general setting and with considerable greater precision as was so far
available. This includes a sharp uncertainty principle relating all low-lying
eigenvalues to mean times of metastable transitions, a relation between the
support of eigenfunctions and the attractor of a metastable state, and sharp
estimates on the convergence of probability distribution of the metastable
transition times to the exponential distribution.

</DOC>
<DOC>
<DOCNO> 151973 </DOCNO>
Comments on the Confinement from Dilaton-Gluon Coupling in QCD


  In this talk, I report on a work done in collaboration with R. Markazi and
E.H. Saidi [1].

</DOC>
<DOC>
<DOCNO> 178874 </DOCNO>
Study for the s-wave in ^{10}Li with analysis of cross-sections


  We study the effect of s-wave cross-sections in $^{4}$He+$n$ and $^{9}$Li+$n$
elastic scattering reactions by using the Jost function method (JFM). In
$^{5}$He ($^{4}$He+$n$), the s-wave pole of the $S$-matrix does not contribute
so much to the total cross-section. On the other hand, in $^{10}$Li
($^{9}$Li+$n$), the s-wave component can not be neglected due to a relatively
strong attraction for the s-waves of the core+$n$ potential. It is shown that
the $^{9}$Li-$n$ potential, which is microscopically derived by taking into
account the pairing-blocking effect for a p-wave neutron, reproduces the s-wave
pole close to the $^{9}$Li+$n$ threshold and strongly enhances the s-wave
cross-section near the threshold.

</DOC>
<DOC>
<DOCNO> 152492 </DOCNO>
Nonperturbative contributions in quantum-mechanical models: the


  We review the euclidean path-integral formalism in connection with the
one-dimensional non-relativistic particle. The configurations which allow to
construct a semiclassical approximation classify themselves into either
topological (instantons) and non-topological (bounces) solutions. While the
instantons dominate the tunneling phenomena between classical vacua, the
bounces describe the decay from a false vacuum to the true one. The quantum
amplitudes consist on an exponential associated with the classical contribution
multiplied by the fluctuation factor which is given by a functional
determinant. The eigenfunctions as well as the energy eigenvalues of the
quadratic operators at issue can be written in closed form due to the
shape-invariance property. Accordingly we resort to the zeta-function method to
compute the functional determinants in a systematic way. The effect of the
multi-instantons configurations is also carefully considered. To illustrate the
instanton calculus in a relevant model we go to the double-well potential. Once
we carry out the Wick rotation the problem transforms into a two-humped
potential. Another popular case is the periodic-potential where the initial
levels split into bands. The quantum decay rate of the metastable states in a
cubic model is evaluated by means of the bounce-like solution.

</DOC>
<DOC>
<DOCNO> 170587 </DOCNO>
Quantum entanglement and classical separability in NMR computing


  In the discussion about the quantumness of NMR computation a conclusion is
done that computational states are separable and therefore can not be
entangled. This conclusion is based on the assumption that the initial density
matrix of an individual molecule coincides with whole sample molecules
distribution over single molecule energy levels. This means that quantum
stochasticity is replaced by classical stochasticity. In the present paper it
is shown, that quantum NMR computation can create genuine entangled states if
initial system states are thermodynamical equilibrium ones. A separability
analysis problem can arise when one interprets the readout signal from whole
sample.

</DOC>
<DOC>
<DOCNO> 122639 </DOCNO>
Radiation-driven winds of hot stars. XIII. A description of NLTE line


  We present significant improvements of our approach in constructing detailed
atmospheric models and synthetic spectra for hot luminous stars:
  1. A sophisticated and consistent description of line blocking and
blanketing. Our solution concept renders the line blocking influence on the
ionizing fluxes (mainly the EUV and UV are affected) in identical quality as
the synthetic high resolution spectra representing the observable region. Line
blanketing is properly accounted for in the energy balance.
  2. A considerably improved and enhanced atomic data archive providing the
basis for a detailed multilevel NLTE treatment of the metal ions (from C to Zn)
and an adequate representation of line blocking and the radiative line
acceleration.
  3. A revised inclusion of EUV and X-ray radiation produced by cooling zones
originating from shock heated matter.
  This new tool not only provides an easy to use method for O-star diagnostics,
whereby physical constraints on the properties of stellar winds, stellar
parameters, and abundances can be obtained via a comparison of observed and
synthetic spectra, but also allows the astrophysically important information
about the ionizing fluxes of hot stars to be determined automatically. Results
illustrating this are discussed by means of a basic model grid calculated for
O-stars with solar metallicity. To further demonstrate the astrophysical
potential of our new method we provide a first detailed spectral diagnostic
determination of the stellar parameters, the wind parameters, and the
abundances by an exemplary application to the O9.5Ia supergiant alpha Cam.

</DOC>
<DOC>
<DOCNO> 118519 </DOCNO>
Massive star clusters in dwarf starburst galaxies


  I will discuss the presence of massive star clusters in starburst galaxies
with an emphasis on low mass galaxies outside the local group. I will show that
such galaxies, with respect to their mass and luminosity, may be very rich in
young luminous clusters.

</DOC>
<DOC>
<DOCNO> 100465 </DOCNO>
On p-adic path integral


  Feynman's path integral is generalized to quantum mechanics on p-adic space
and time. Such p-adic path integral is analytically evaluated for quadratic
Lagrangians. Obtained result has the same form as that one in ordinary quantum
mechanics.

</DOC>
<DOC>
<DOCNO> 121132 </DOCNO>
The Theory of Steady State Super-Eddington Winds and its Application to


  We present a model for steady state winds of systems with super-Eddington
luminosities. These radiatively driven winds are expected to be optically thick
and clumpy as they arise from an instability driven porous atmosphere. The
model is then applied to derive the mass loss observed in bright classical
novae. The main results are:
  1) A general relation between the mass loss rate and the total luminosity in
super-Eddington systems.
  2) A quantitative agreement between the observed luminosity evolution which
is used to predict both the mass loss and temperature evolution, and their
observations.
  3) An agreement between the predicted average integrated mass loss of novae
as a function of WD mass and its observations.
  4) A natural explanation for the `transition phase' of novae.
  5) Agreement with eta Carinae which was used to double check the theory. The
prediction for the mass shed in the star's great eruption agrees with
observations to within the measurement error.

</DOC>
<DOC>
<DOCNO> 9871 </DOCNO>
Dipolar Interactions in Superconductor-Ferromagnet Heterostructures


  We consider a simple model for a superlattice composed of a thin magnetic
film placed between two bulk superconductors. The magnetic film is modelled by
a planar but otherwise arbitrary distribution of magnetic dipoles and the
superconductors are treated in the London approximation. Due to the linearity
of the problem, we are able to compute the magnetic energy of the film in the
presence of the superconductors. We show that in the case of small wavenumbers
compared to the inverse London penetration depth, the magnetic energy resembles
the energy of a distribution of magnetisation in a two dimensional space.
Possible experimental applications of these results are discussed.

</DOC>
<DOC>
<DOCNO> 122843 </DOCNO>
Predicting the peculiar velocities of nearby PSC-z galaxies using the


  We use the Least Action Principle to predict the peculiar velocities of PSC-z
galaxies inside $cz=2000$\km. Linear theory is used to account for tidal
effects to $cz=15000$\km, and we iterate galaxy positions to account for
redshift distortions. As the Least Action Principle is valid beyond Linear
theory, we can predict reliable peculiar velocities even for very nearby
galaxies (ie $cz \leq 500$\km). These predicted peculiar velocities are then
compared with the observed velocities of 12 galaxies with Cepheid distances.
The combination of the PSC-z galaxy survey (with its large sky coverage and
uniform selection), with the accurate Cepheid distances, makes this comparison
relatively free from systematic effects. We find that galaxies are good tracers
of the mass, even at small ($\leq 10$\mpc) scales; and under the assumption of
no biasing, $0.25 \leq \beta \leq 0.75$ (at 90% confidence). We use the
reliable predicted peculiar velocities to estimate the Hubble constant \ho from
the local volume without ``stepping up'' the distance ladder, finding a
confidence range of 65-75\kmM (at 90% confidence).

</DOC>
<DOC>
<DOCNO> 7771 </DOCNO>
Theory of electron transport in normal metal/superconductor junctions


  On the basis of the Keldysh method of non-equilibrium systems, we develop a
theory of electron tunneling in normal-metal/superconductor junctions. By using
the tunneling Hamiltonian model (being appropriate for the tight-binding
systems), the tunneling current can be exactly obtained in terms of the
equilibrium Green functions of the normal metal and the superconductor. We
calculate the conductance of various junctions. The discrepancy between the
present treatment and the well-known scheme by Blonder, Tinkham, and Klapwijk
is found for some junctions of low interfacial potential barrier.

</DOC>
<DOC>
<DOCNO> 67812 </DOCNO>
Cosmological Aspects of Heterotic M-theory


  In this talk we discuss a few relevant aspects of heterotic M-theory. These
are the stabilization of the two relevant moduli (the length of the eleventh
segment (pi rho) and the volume of the internal six manifold (V)) in models
where supersymmetry is broken by multiple gaugino condensation and
non-perturbative corrections to the Kahler potential; the existence of almost
flat directions in the scalar potential; the possibility of lifting them, and
their role in constructing a viable model of inflation. Finally, we review the
status of the moduli problem within these models. T

</DOC>
<DOC>
<DOCNO> 7864 </DOCNO>
Pseudogap effects on the c-axis charge dynamics in copper oxide


  The c-axis charge dynamics of copper oxide materials in the underdoped and
optimally doped regimes has been studied by considering the incoherent
interlayer hopping. It is shown that the c-axis charge dynamics for the chain
copper oxide materials is mainly governed by the scattering from the in-plane
fluctuation, and the c-axis charge dynamics for the no-chain copper oxide
materials is dominated by the scattering from the in-plane fluctuation
incorporating with the interlayer disorder, which would be suppressed when the
holon pseudogap opens at low temperatures and lower doping levels, leading to
the crossovers to the semiconducting-like range in the c-axis resistivity and
the temperature linear to the nonlinear range in the in-plane resistivity.

</DOC>
<DOC>
<DOCNO> 120763 </DOCNO>
Search for young stars among ROSAT All-Sky Survey X-ray sources in and


  We present the ROSAT All-Sky Survey data in a 126 deg^2 area in and around
the CrA star forming region. With low-resolution spectroscopy of unidentified
ROSAT sources we could find 19 new pre-main sequence stars, two of which are
classical T Tauri stars, the others being weak-lined. The spectral types of
these new T Tauri stars range from F7 to M6. The two new classical T Tauri
stars are located towards two small cloud-lets outside of the main CrA cloud.
They appear to be ~10 Myrs old, by comparing their location in the H-R diagram
with isochrones for an assumed distance of 130 pc, the distance of the main CrA
dark cloud. The new off-cloud weak-line T Tauri stars may have formed in
similar cloud-lets, which have dispersed recently. High-resolution spectra of
our new T Tauri stars show that they have significantly more lithium absorption
than zero-age main-sequence stars of the same spectral type, so that they are
indeed young. From those spectra we also obtained rotational and radial
velocities. For some stars we found the proper motion in published catalogs.
The direction and velocity of the 3D space motion - south relative to the
galatic plane - of the CrA T Tauri stars is consistent with the dark cloud
being formed originally by a high-velocity cloud impact onto the galactic
plane, which triggered the star formation in CrA. We also present VRIJHK
photometry for most of the new T Tauri stars to derive their luminosities,
ages, and masses.

</DOC>
<DOC>
<DOCNO> 83136 </DOCNO>
Fages' Theorem and Answer Set Programming


  We generalize a theorem by Francois Fages that describes the relationship
between the completion semantics and the answer set semantics for logic
programs with negation as failure. The study of this relationship is important
in connection with the emergence of answer set programming. Whenever the two
semantics are equivalent, answer sets can be computed by a satisfiability
solver, and the use of answer set solvers such as smodels and dlv is
unnecessary. A logic programming representation of the blocks world due to
Ilkka Niemelae is discussed as an example.

</DOC>
<DOC>
<DOCNO> 67821 </DOCNO>
CP Violation with Three Oscillating Neutrino Flavours


  We explore the prospects of observing leptonic CP violation in a neutrino
factory in the context of a scenario with three strongly oscillating neutrinos
able to account for the solar, the atmospheric and the LSND results. We address
also the problems related with the fake asymmetries induced by the experimental
device and by the presence of matter.

</DOC>
<DOC>
<DOCNO> 119023 </DOCNO>
Broad iron lines in Active Galactic Nuclei


  An intrinsically narrow line emitted by an accretion disk around a black hole
appears broadened and skewed as a result of the Doppler effect and
gravitational redshift. The fluorescent iron line in the X-ray band at
6.4-6.9keV is the strongest such line and is seen in the X-ray spectrum of many
active galactic nuclei and, in particular, Seyfert galaxies. It is an important
diagnostic with which to study the geometry and other properties of the
accretion flow very close to the central black hole. The broad iron line
indicates the presence of a standard thin accretion disk in those objects,
often seen at low inclination. The broad iron line has opened up strong
gravitational effects around black holes to observational study with
wide-reaching consequences for both astrophysics and physics.

</DOC>
<DOC>
<DOCNO> 119970 </DOCNO>
Nonlinear Evolution of Very Small Scale Cosmological Baryon


  The evolution of baryon density perturbations on very small scales is
investigated. In particular, the nonlinear growth induced by the radiation drag
force from the shear velocity field on larger scales during the recombination
epoch, which is originally proposed by Shaviv in 1998, is studied in detail. It
is found that inclusion of the diffusion term which Shaviv neglected in his
analysis results in rather mild growth whose growth rate is $\ll 100$ instead
of enormous amplification $\sim 10^4$ of Shaviv's original claim since the
diffusion suppresses the growth. The growth factor strongly depends on the
amplitude of the large scale velocity field. The nonlinear growth mechanism is
applied to density perturbations of general adiabatic cold dark matter (CDM)
models. In these models, it has been found in the previous works that the
baryon density perturbations are not completely erased by diffusion damping if
there exists gravitational potential of CDM. With employing the perturbed rate
equation which is derived in this paper, the nonlinear evolution of baryon
density perturbations is investigated. It is found that: (1) The nonlinear
growth is larger for smaller scales. This mechanism only affects the
perturbations whose scales are smaller than $\sim 10^2M_\odot$, which are
coincident with the stellar scales. (2) The maximum growth factors of baryon
density fluctuations for various COBE normalized CDM models are typically less
than factor 10 for $3-\sigma$ large scale velocity peaks. (3) The growth factor
depends on $\Omega_{\rm b}$.

</DOC>
<DOC>
<DOCNO> 8407 </DOCNO>
Free Energy Landscape Of Simple Liquids Near The Glass Transition


  Properties of the free energy landscape in phase space of a dense hard sphere
system characterized by a discretized free energy functional of the
Ramakrishnan-Yussouff form are investigated numerically. A considerable number
of glassy local minima of the free energy are located and the distribution of
an appropriately defined ``overlap'' between minima is calculated. The process
of transition from the basin of attraction of a minimum to that of another one
is studied using a new ``microcanonical'' Monte Carlo procedure, leading to a
determination of the effective height of free energy barriers that separate
different glassy minima. The general appearance of the free energy landscape
resembles that of a putting green: deep minima separated by a fairly flat
structure. The growth of the effective free-energy barriers with increasing
density is consistent with the Vogel-Fulcher law, and this growth is primarily
driven by an entropic mechanism.

</DOC>
<DOC>
<DOCNO> 122197 </DOCNO>
An ionizing UV background dominated by massive stars


  We discuss implications of a stellar-dominated UV background at high
redshifts. The composite spectrum of 29 LBGs evaluated by Steidel etal (2000)
at <z>=3.4 can be well fit by a stellar population with ongoing star formation,
a Salpeter initial mass function, modest or negligible dust reddening, and no
intrinsic HI photoelectric absorption. Fading starbursts in which star
formation has ceased for 10^7 yr or more cannot reproduce the observed flux
shortward of 1 Ryd.The escape fraction of H-ionizing photons must be close to
100 percent for the observed sample of LBGs. The spectrum of ionizing photons
produced by a stellar population with ongoing star formation is similar to that
of QSOs between 1 and 3 Ryd, becomes softer between 3 and 4 Ryd and drops
sharply shortward of 4 Ryd. A galaxy-dominated UV background appears
inconsistent with the observed HeII/HI opacity ratio at z=2.4, but might be
able to explain the SiIV/CIV abundances measured at z>3 in absorption spectra.
A scenario may be emerging where star-forming galaxies reionized intergalactic
hydrogen at $z>6$ and dominate the 1 Ryd metagalactic flux at z>3, with
quasi-stellar sources taking over at low redshifts. If the large amplitude of
the H-ionizing flux estimated by Steidel etal is correct, hydrodynamical
simulations of structure formation in the IGM require a baryon density (to
explain the observed Lyalpha opacity in absorption spectra) which is similar to
or larger than that favoured by recent CMB experiments, and is inconsistent
with standard nucleosynthesis values.

</DOC>
<DOC>
<DOCNO> 71510 </DOCNO>
Constraints on the neutrino mass and the cosmological constant from


  The observational data on the large scale structure (LSS) of the Universe are
used to establish the upper limit on the neutrino content marginalized over all
other cosmological parameters within the class of adiabatic inflationary
models. It is shown that the upper 2$\sigma$ limit on the neutrino content can
be expressed in the form $\Omega_{\nu}h^2/N_{\nu}^{0.64}\le0.042$ or, via the
neutrino mass, $m_{\nu}\le4.0$eV.

</DOC>
<DOC>
<DOCNO> 178529 </DOCNO>
Limitations of the number selfconsistent Random Phase Approximation


  The Quasiparticle Random Phase Approximation equations are solved taking into
account the Pauli Principle at the expectation value level, and allowing
changes in the mean field occupation numbers to minimize the energy while
having the correct number of particles in the correlated vacuum. The study of
Fermi pn excitations in $^{76}$Ge using a realistic Hilbert space shows that
the pairing energy gaps in the modified mean field are diminished up to one
half of the experimental value when strong proton-neutron correlations are
present. Additionally, the Ikeda sum rule for Fermi transitions is violated due
to the lack of scattering terms in the phonon operators. These results call for
a critical revision of the double beta decay half-lives estimated using the
QRPA extensions when standard QRPA calculations collapse.

</DOC>
<DOC>
<DOCNO> 7916 </DOCNO>
Glassy properties and localization of interacting electrons in


  We present a computer simulation study of a disordered two-dimensional system
of localized interacting electrons at thermal equilibrium. It is shown that the
configuration of occupied sites within the Coulomb gap persistently changes at
temperatures much less than the gap width. This is accompanied by large time
dependent fluctuations of the site energies. The observed thermal equilibration
at low temperatures suggests a possible glass transition only at T=0. We
interpret the strong fluctuations in the occupation numbers and site energies
in terms of the drift of the system between multiple energy minima. The results
also imply that interacting electrons may be effectively delocalized within the
Coulomb gap. Insulating properties, such as hopping conduction, appear as a
result of long equilibration times associated with glassy dynamics. This may
shine new light on the relation between the metal-insulator transition and
glassy behavior.

</DOC>
<DOC>
<DOCNO> 102080 </DOCNO>
Return time statistics via inducing


  We prove that return time statistics of a dynamical system do not change if
one passes to an induced (i.e. first return) map. We apply this to show
exponential return time statistics in i) smooth interval maps with
nowhere-dense critical orbits and ii) certain interval maps with neutral fixed
points. The method also applies to iii) certain quadratic maps of the complex
plane.

</DOC>
<DOC>
<DOCNO> 170456 </DOCNO>
Charge based quantum computer without charge transfer


  A novel implementation of a charge based quantum computer is proposed. There
is no charge transfer during calculation, therefore, uncontrollable
entanglement between qubits due to long-range Coulomb forces is suppressed.
High-speed computation with 1ps per an operation looks as feasible.

</DOC>
<DOC>
<DOCNO> 71362 </DOCNO>
Inelastic diffractive proton-proton scattering in nonperturbative QCD


  We examine diffractive proton-proton scattering. Using a functional integral
approach we derive the scattering amplitudes, which are governed by the
expectation value of lightlike Wegner-Wilson loops. This expectation value is
then evaluated using a cumulant expansion and the model of the stochastic
vacuum. From the scattering amplitudes we calculate total and differential
cross sections for high centre of mass energy and small momentum transfer and
compare with experiments.

</DOC>
<DOC>
<DOCNO> 85244 </DOCNO>
The monodromy matrix method of solving an exterior boundary value


  A procedure is described for matching a given stationary axisymmetric perfect
fluid solution to a not necessarily asymptotically flat vacuum exterior. Using
data on the zero pressure surface, the procedure yields the Ernst potential of
the matching vacuum metric on the symmetry axis. From this the full metric can
be constructed using a variety of well established procedures.

</DOC>
<DOC>
<DOCNO> 121565 </DOCNO>
The Cosmological Evolution of Quasar Damped Lyman-Alpha Systems


  We present results from an efficient, non-traditional survey to discover
damped Lyman-alpha (DLA) absorption-line systems with neutral hydrogen column
densities N(HI)>2x10^{20} atoms cm^{-2} and redshifts z<1.65. Contrary to
previous studies at higher redshift that showed a decrease in the cosmological
mass density of neutral gas in DLA absorbers, Omega_{DLA}, with time, our
results indicate that Omega_{DLA} is consistent with remaining constant from
redshifts z \approx 4 to z \approx 0.5. There is no evidence that Omega_{DLA}
is approaching the value at z=0. Other interesting results from the survey are
also presented.

</DOC>
<DOC>
<DOCNO> 84374 </DOCNO>
Cosmic String Wakes in Scalar-Tensor Gravities


  The formation and evolution of cosmic string wakes in the framework of a
scalar-tensor gravity are investigated in this work. We consider a simple model
in which cold dark matter flows past an ordinary string and we treat this
motion in the Zel'dovich approximation. We make a comaprison between our
results and previous results obtained in the context of General Relativity. We
propose a mechanism in which the contribution of the scalar field to the
evolution of the wakes may lead to a cosmological observation.

</DOC>
<DOC>
<DOCNO> 174457 </DOCNO>
Very high rotational frequencies and band termination in 73Br


  Rotational bands in 73Br have been investigated up to spins of 65/2 using the
EUROBALL III spectrometer. One of the negative-parity bands displays the
highest rotational frequency 1.85 MeV reported to date in nuclei with mass
number greater than 25. At high frequencies, the experimental dynamic moment of
inertia for all bands decrease to very low values, indicating a loss of
collectivity. The bands are described in the configuration-dependent cranked
Nilsson-Strutinsky model. The calculations indicate that one of the
negative-parity bands is observed up to its terminating single-particle state
at spin 63/2. This result establishes the first band termination case in the A
= 70 mass region.

</DOC>
<DOC>
<DOCNO> 170472 </DOCNO>
Bound entangled Gaussian states


  We discuss the entanglement properties of bipartite states with Gaussian
Wigner functions. Separability and the positivity of the partial transpose are
characterized in terms of the covariance matrix of the state, and it is shown
that for systems composed of a single oscillator for Alice and an arbitrary
number for Bob, positivity of the partial transpose implies separability.
However, this implications fails with two oscillators on each side, as we show
by a five parameter family of explicit counterexamples.

</DOC>
<DOC>
<DOCNO> 11044 </DOCNO>
A Quantum Analogue of the Jarzynski Equality


  A quantum analogue of the Jarzynski equality is constructed. This equality
connects an ensemble average of exponentiated work with the Helmholtz
free-energy difference in a nonequilibrium switching process subject to a
thermal heat bath. To confirm its validity in a practical situation, we also
investigate an open quantum system that is a spin 1/2 system with a scanning
magnetic field interacting with a thermal heat bath. As a result, we find that
the quantum analogue functions well.

</DOC>
<DOC>
<DOCNO> 170010 </DOCNO>
Perturbative method for generalized spectral decompositions


  Imposing analytic properties to states and observables we construct a
perturbative method to obtain a generalized biorthogonal system of eigenvalues
and eigenvectors for quantum unstable systems. A decay process can be described
using this generalized spectral decomposition, and the final generalized state
is obtained.

</DOC>
<DOC>
<DOCNO> 8186 </DOCNO>
Single and Paired Point Defects in a 2D Wigner Crystal


  Using the path-integral Monte Carlo method, we calculate the energy to form
single and pair vacancies and interstitials in a two-dimensional Wigner crystal
of electrons. We confirm that the lowest-lying energy defects of a 2D electron
Wigner crystal are interstitials, with a creation energy roughly 2/3 that of a
vacancy. The formation energy of the defects goes to zero near melting,
suggesting that point defects might mediate the melting process. In addition,
we find that the interaction between defects is strongly attractive, so that
most defects will exist as bound pairs.

</DOC>
<DOC>
<DOCNO> 151126 </DOCNO>
D-branes, Symplectomorphisms and Noncommutative Gauge Theories


  It is shown that the dual of the double compactified D=11 Supermembrane and a
suitable compactified D=10 Super 4D-brane with nontrivial wrapping on the
target space may be formulated as noncommutative gauge theories. The Poisson
bracket over the world-volume is intrinsically defined in terms of the minima
of the hamiltonian of the theory, which may be expressed in terms of a non
degenerate 2-form. A deformation of the Poisson bracket in terms of the Moyal
brackets is then performed. A noncommutative gauge theory in terms of the Moyal
star bracket is obtained. It is shown that all these theories may be described
in terms of symplectic connections on symplectic fibrations. The world volume
being its base manifold and the (sub)group of volume preserving diffeomorphisms
generate the symplectomorphisms which preserve the (infinite dimensional)
Poisson bracket of the fibration.

</DOC>
<DOC>
<DOCNO> 119149 </DOCNO>
The Bispectrum of IRAS Galaxies


  We compute the bispectrum for the galaxy distribution in the IRAS QDOT, 2Jy,
and 1.2Jy redshift catalogs for wavenumbers 0.05<k<0.2 h/Mpc and compare the
results with predictions from gravitational instability in perturbation theory.
Taking into account redshift space distortions, nonlinear evolution, the survey
selection function, and discreteness and finite volume effects, all three
catalogs show evidence for the dependence of the bispectrum on configuration
shape predicted by gravitational instability. Assuming Gaussian initial
conditions and local biasing parametrized by linear and non-linear bias
parameters b_1 and b_2, a likelihood analysis yields 1/b_1 =
1.32^{+0.36}_{-0.58}, 1.15^{+0.39}_{-0.39} and b_2/b_1^2=-0.57^{+0.45}_{-0.30},
-0.50^{+0.31}_{-0.51}, for the for the 2Jy and 1.2Jy samples, respectively.
This implies that IRAS galaxies trace dark matter increasingly weakly as the
density contrast increases, consistent with their being under-represented in
clusters. In a model with chi^2 non-Gaussian initial conditions, the bispectrum
displays an amplitude and scale dependence different than that found in the
Gaussian case; if IRAS galaxies do not have bias b_1> 1 at large scales, \chi^2
non-Gaussian initial conditions are ruled out at the 95% confidence level. The
IRAS data do not distinguish between Lagrangian or Eulerian local bias.

</DOC>
<DOC>
<DOCNO> 118662 </DOCNO>
Nature of the background ultraviolet radiation field


  We have tried to determine the flux of the ultraviolet background radiation
field from the column density ratios of various ions in several absorption
systems observed in the spectra of QSOs. We find that in most cases the flux is
considerably higher than what has been estimated to be contributed by the AGNs.
The excess flux could originate locally in hot stars. In a few cases we have
been able to show that such galactic flux can only contribute a part of the
total required flux. The results suggest that the background gets a significant
contribution from an unseen QSO population.

</DOC>
<DOC>
<DOCNO> 121975 </DOCNO>
The formation of G-band bright points. I: Standard LTE modelling


  Assuming LTE, we synthesise solar G band spectra from the semiempirical
flux-tube model of Briand Solanki (1995). The results agree with observed
G-band bright-point contrasts within the uncertainty set by the amount of
scattered light. We find that it is the weakening of spectral lines within the
flux tube that makes the bright-point contrast in the G band exceed the
continuum contrast. We also synthesise flux-tube spectra assuming LTE for the
full wavelength range from UV to IR, and identify other promising passbands for
flux-tube observations.

</DOC>
<DOC>
<DOCNO> 13992 </DOCNO>
Scaling properties of the critical behavior in the dilute


  Critical scattering analyses for dilute antiferromagnets are made difficult
by the lack of predicted theoretical line shapes beyond mean-field models.
Nevertheless, with the use of some general scaling assumptions we have
developed a procedure by which we can analyze the equilibrium critical
scattering in these systems for H=0, the random-exchange Ising model, and, more
importantly, for H>0, the random-field Ising model. Our new fitting approach,
as opposed to the more conventional techniques, allows us to obtain the
universal critical behavior exponents and amplitude ratios as well as the
critical line shapes. We discuss the technique as applied to
Fe(0.93)Zn(0.07)F2. The general technique, however, should be applicable to
other problems where the scattering line shapes are not well understood but
scaling is expected to hold.

</DOC>
<DOC>
<DOCNO> 11321 </DOCNO>
Nonadiabatic Contribution to the Quasiparticle Self-Energy in Systems


  We investigate effects of a nonadiabatic electron-phonon(boson) interaction
on the quasiparticle self-energy in the lowest order in the coupling constant.
Existing approaches either overestimate, or underestimate these effects because
of different approximations for momentum and frequency dependences of the
vertex corrections. The connection between the nonadiabaticity and a possible
instability of the interacting Fermi system is discussed as well.

</DOC>
<DOC>
<DOCNO> 85318 </DOCNO>
Exact inhomogeneous Einstein-Maxwell-Dilaton cosmologies


  We present solution generating techniques which permit to construct exact
inhomogeneous and anisotropic cosmological solutions to a four-dimensional low
energy limit of string theory containing non-minimally interacting
electromagnetic and dilaton fields. Some explicit homogeneous and inhomogeneous
cosmological solutions are constructed. For example, inhomogeneous exact
solutions presenting Gowdy - type EMD universe are obtained. The asymptotic
behaviour of the solutions is investigated. The asymptotic form of the metric
near the initial singularity has a spatially varying Kasner form. The character
of the space-time singularities is discussed. The late evolution of the
solutions is described by a background homogeneous and anisotropic universe
filled with weakly interacting gravitational, dilatonic and electromagnetic
waves.

</DOC>
<DOC>
<DOCNO> 117648 </DOCNO>
ISO Spectroscopy of H2 in Star Forming Regions


  We have studied molecular hydrogen emission in a sample of 21 YSOs using
spectra obtained with the Infrared Space Observatory (ISO). H2 emission was
detected in 12 sources and can be explained as arising in either a shock,
caused by the interaction of an outflow from an embedded YSO with the
surrounding molecular cloud, or in a PDR surrounding an exposed young
early-type star. The distinction between these two mechanisms can not always be
made from the pure rotational H2 lines alone. Other tracers, such as PAH
emission or [S I] 25.25 micron emission, are needed to identify the H2 heating
mechanism. No deviations from a 3:1 ortho/para ratio of H2 were found. Both
shocks and PDRs show a warm and a hot component in H2, which we explain as
thermal emission from warm molecular gas (warm component), or UV-pumped
infrared fluorescence in the case of PDRs and the re-formation of H2 for shocks
(hot component).

</DOC>
<DOC>
<DOCNO> 101113 </DOCNO>
On minimal eigenvalues of Schrodinger operators on manifolds


  We consider the problem of minimizing the eigenvalues of the Schr\"{o}dinger
operator $H=-\Delta+\alpha F(\ka)$ ($\alpha>0$) on a compact $n-$manifold
subject to the restriction that $\ka$ has a given fixed average $\ka_{0}$.
  In the one-dimensional case our results imply in particular that for
$F(\ka)=\ka^{2}$ the constant potential fails to minimize the principal
eigenvalue for $\alpha>\alpha_{c}=\mu_{1}/(4\ka_{0}^{2})$, where $\mu_{1}$ is
the first nonzero eigenvalue of $-\Delta$. This complements a result by Exner,
Harrell and Loss (math-ph/9901022), showing that the critical value where the
circle stops being a minimizer for a class of Schr\"{o}dinger operators
penalized by curvature is given by $\alpha_{c}$. Furthermore, we show that the
value of $\mu_{1}/4$ remains the infimum for all $\alpha>\alpha_{c}$. Using
these results, we obtain a sharp lower bound for the principal eigenvalue for a
general potential.
  In higher dimensions we prove a (weak) local version of these results for a
general class of potentials $F(\ka)$, and then show that globally the infimum
for the first and also for higher eigenvalues is actually given by the
corresponding eigenvalues of the Laplace-Beltrami operator and is never
attained.

</DOC>
<DOC>
<DOCNO> 84540 </DOCNO>
Generating conjecture and Einstein-Maxwell field of plane symmetry


  For the plane symmetry we have found the electro-vacuum exact solutions of
the Einstein-Maxwell equations and we have shown that one of them is equivalent
to the McVittie solution of a charged infinite thin plane. The analytical
extension has been accomplished and the Penrose conformal diagram has been
obtained as well.

</DOC>
<DOC>
<DOCNO> 151053 </DOCNO>
The no-ghost theorem for string theory in curved backgrounds with a flat


  It is well-known that the standard no-ghost theorem can be extended
straightforwardly to the general c=26 CFT on R^{d-1,1} \times K, where 2 \leq d
\leq 26 and K is a compact unitary CFT of appropriate central charge. We prove
the no-ghost theorem for d=1, i.e., when only the timelike direction is flat.
This is done using the technique of Frenkel, Garland and Zuckerman.

</DOC>
<DOC>
<DOCNO> 118980 </DOCNO>
The Hubble Deep Fields


  The Hubble space telescope observations of the northern Hubble deep field,
and more recently its counterpart in the south, provide detections and
photometry for stars and field galaxies to the faintest levels currently
achievable, reaching magnitudes V ~ 30. Since 1995, the northern Hubble deep
field has been the focus of deep surveys at nearly all wavelengths. These
observations have revealed many properties of high redshift galaxies, and have
contributed important data on the stellar mass function in the Galactic halo.

</DOC>
<DOC>
<DOCNO> 116365 </DOCNO>
Performance of discrete heat engines and heat pumps in finite time


  The performance in finite time of a discrete heat engine with internal
friction is analyzed. The working fluid of the engine is composed of an
ensemble of noninteracting two level systems. External work is applied by
changing the external field and thus the internal energy levels. The friction
induces a minimal cycle time. The power output of the engine is optimized with
respect to time allocation between the contact time with the hot and cold baths
as well as the adiabats. The engine's performance is also optimized with
respect to the external fields. By reversing the cycle of operation a heat pump
is constructed. The performance of the engine as a heat pump is also optimized.
By varying the time allocation between the adiabats and the contact time with
the reservoir a universal behavior can be identified. The optimal performance
of the engine when the cold bath is approaching absolute zero is studied. It is
found that the optimal cooling rate converges linearly to zero when the
temperature approaches absolute zero.

</DOC>
<DOC>
<DOCNO> 99661 </DOCNO>
Toda p-brane black holes and polynomials related to Lie algebras


  Black hole generalized p-brane solutions for a wide class of intersection
rules are obtained. The solutions are defined on a manifold that contains a
product of n - 1 Ricci-flat internal spaces. They are defined up to a set of
functions H_s obeying non-linear differential equations equivalent to Toda-type
equations with certain boundary conditions imposed. A conjecture on polynomial
structure of governing functions H_s for intersections related to semisimple
Lie algebras is suggested. This conjecture is proved for Lie algebras: A_m,
C_{m+1}, m = 1,2,.... For simple Lie algebras the powers of polynomials
coincide with the components of the dual Weyl vector in the basis of simple
roots. The coefficients of polynomials depend upon the extremality parameter
\mu >0. In the extremal case \mu = 0 such polynomials were considered
previously by H. L\"u, J. Maharana, S. Mukherji and C.N. Pope. Explicit
formulas for A_2-solution are obtained. Two examples of A_2-dyon solutions,
i.e. dyon in D = 11 supergravity with M2 and M5 branes intersecting at a point
and Kaluza-Klein dyon, are considered.

</DOC>
<DOC>
<DOCNO> 120268 </DOCNO>
Seeing Galaxies Through Thick and Thin: II. Direct Measures of


  We use slit spectroscopy of overlapping pairs of galaxies to directly
determine the extinction in disks of foreground spiral galaxies. The Doppler
shifts of pair members are determined via cross-correlation and their relative
correlation amplitudes are used to separate their contributions to the combined
spectra in regions of overlap. This spectroscopic approach is less subject to
stringent symmetry constraints than our previous purely photometric analyses.
Extinctions of foreground members were obtained for 6 of the candidates in our
sample of 18 mostly spiral/spiral pairs, when the signal to noise and velocity
difference were suitable. In agreement with our previous imaging results, we
find that the extinction in interarm regions is very modest, typically A_B=0.1
mag (corrected to face on), while spiral arms exhibit higher extinctions of 0.3
mag.

</DOC>
<DOC>
<DOCNO> 122627 </DOCNO>
A Near-Infrared Imaging Survey of the Chamaeleon I Dark Cloud


  We describe a near-infrared imaging survey covering approximately 1 square
deg of the Chamaeleon I dark cloud. The survey is complete for K < 15.0, H <
16.0, and J < 16.5, roughly two magnitudes more sensitive than previous large
scale surveys. We use the large number of background stars detected to derive
an accurate near-infrared extinction law for the cloud and select new candidate
members with near-infrared color excesses. We list about 100 candidates of the
cloud with K > 12.0, based on their positions in the J-H, H-K color-color
diagram. These new stars have low luminosities (K > 12 -- 16, H-K > 0.5 -- 1.5)
and may have masses close to or even below the hydrogen burning limit.

</DOC>
<DOC>
<DOCNO> 170325 </DOCNO>
"Shaking" of an atom in a non-stationary cavity


  We consider an atom interacting with a quantized electromagnetic field inside
a cavity with variable parameters. The atom in the ground state located in the
initially empty cavity can be excited by variation of cavity parameters. We
have discovered two mechanisms of atomic excitation. The first arises due to
the interaction of the atom with the non-stationary electromagnetic field
created by modulation of cavity parameters. If the characteristic time of
variation of cavity parameters is of the order of the atomic transition time,
the processes of photon creation and atomic excitation are going on
simultaneously and hence excitation of the atom cannot be reduced to trivial
absorption of the photons produced by the dynamical Casimir effect. The second
mechanism is "shaking" of the atom due to fast modulation of its ground state
Lamb shift which takes place as a result of fast variation of cavity arameters.
The last mechanism has no connection with the vacuum dynamical Casimir effect.
Moreover, it opens a new channel of photon creation in the non-stationary
cavity. Nevertheless, the process of photon creation is altered by the presence
of the atom in the cavity, even if one disregards the existence of the new
channel. In particular, it removes the restriction for creation of only even
number of photons and also changes the expectation value for the number of
created photons. Our consideration is based on a simple model of a two-level
atom interacting with a single mode of the cavity field. Qualitatively our
results are valid for a real atom in a physical cavity.

</DOC>
<DOC>
<DOCNO> 69522 </DOCNO>
New type of stable Q balls in the gauge-mediated supersymmetry breaking


  We obtain a new type of a stable Q ball in the context of gauge-mediated
supersymmetry breaking in minimal supersymmetric standard model. It is
so-called gravity-mediation type of Q ball, but stable against the decay into
nucleons, since the energy per unit charge is equal to gravitino mass m_{3/2},
which can be smaller than nucleon mass in the gauge-mediation mechanism. We
consider the cosmological consequences in this new Q-ball scenario, and find
that this new type of the Q ball can be considered as the dark matter and the
source for the baryon number of the universe simultaneously.

</DOC>
<DOC>
<DOCNO> 117716 </DOCNO>
Hydrodymanic collimation of GRB fireballs


  Analytic solutions are presented for the hydrodynamic collimation of a
relativistic fireball by a surrounding baryonic wind emanating from a torus.
The opening angle is shown to be the ratio of the power output of the inner
fireball to that of the exterior baryonic wind. The gamma ray burst 990123
might thus be interpreted as a baryon-pure jet with an energy output of order
10$^{50}$ erg or less, collimated by a baryonic wind from a torus with an
energy output of order $10^{52}$ erg.

</DOC>
<DOC>
<DOCNO> 13347 </DOCNO>
Spin-Glass State in $\rm CuGa_2O_4$


  Magnetic susceptibility, magnetization, specific heat and positive muon spin
relaxation (\musr) measurements have been used to characterize the magnetic
ground-state of the spinel compound $\rm CuGa_2O_4$. We observe a spin-glass
transition of the S=1/2 $\rm Cu^{2+}$ spins below $\rm T_f=2.5K$ characterized
by a cusp in the susceptibility curve which suppressed when a magnetic field is
applied. We show that the magnetization of $\rm CuGa_2O_4$ depends on the
magnetic histo Well below $\rm T_f$, the muon signal resembles the dynamical
Kubo-Toyabe expression reflecting that the spin freezing process in $\rm
CuGa_2O_4$ results Gaussian distribution of the magnetic moments. By means of
Monte-Carlo simulati we obtain the relevant exchange integrals between the $\rm
Cu^{2+}$ spins in this compound.

</DOC>
<DOC>
<DOCNO> 117963 </DOCNO>
The Detection of the Diffuse Interstellar Bands in Dusty Starburst


  We report the detection of the Diffuse Interstellar Bands (``$DIBs$'') in the
optical spectra of seven far-infrared-selected starburst galaxies. The
$\lambda$6283.9 \AA and $\lambda$ 5780.5 \AA features are detected with
equivalent widths of $\sim$ 0.4 to 1 \AA and 0.1 to 0.6 \AA respectively. In
the two starbursts with the highest quality spectra (M82 and NGC2146), four
other weaker $DIBs$ at $\lambda$ 5797.0 \AA, 6010.1 \AA, 6203.1 \AA, and 6613.6
\AA are detected with equivalent widths of $\sim$ 0.1 \AA. The region over
which the $DIBs$ can be detected ranges from $\sim$ 1 kpc in the less powerful
starbursts, to several kpc in the more powerful ones. The gas producing the
$DIBs$ is more kinematically quiescent on-average than the gas producing the
strongly-blueshifted $NaI\lambda\lambda$5890,5896 absorption in the same
starbursts. We show that the $DIBs$ in these intense starbursts are remarkably
similar to those in our Galaxy: the relative strengths of the features detected
are similar, and the equivalent widths follow the same dependence as Galactic
$DIBs$ on $E(B-V)$ and $NaI$ column density. While the ISM in starbursts is
heated by a photon and cosmic ray bath that is $\sim$ 10$^3$ times more intense
than in the diffuse ISM of the Milky Way, the gas densities and pressures are
also correspondingly larger in starbursts. This ``homology'' may help explain
the strikingly similar $DIB$ properties.

</DOC>
<DOC>
<DOCNO> 68138 </DOCNO>
The Pomeron as a Finite Sum of Gluon Ladder


  A model for the Pomeron at t=0 is suggested. It is based on the idea of a
finite sum of ladder diagrams in QCD. Accordingly, the number of s-channel
gluon rungs and correspondingly the powers of logarithms in the forward
scattering amplitude depends on the phase space (energy) available, i.e. as
energy increases, progressively new prongs with additional gluon rungs in the
s-channel open. Explicit expressions for the total cross section involving two
and three rungs or, alternatively, three and four prongs (with $\ln^2(s)$ and
$\ln^3(s)$ as highest terms) is fitted to the proton-proton and
proton-antiproton total cross section data in the accelerator region.

</DOC>
<DOC>
<DOCNO> 99553 </DOCNO>
The automorphisms of affine fusion rings


  The fusion rings associated to affine Kac-Moody algebras appear in several
different contexts in math and mathematical physics. In this paper we find all
automorphisms of all affine fusion rings, or equivalently the symmetries of the
corresponding fusion coefficients. Most of these are directly related to
symmetries of the corresponding Coxeter-Dynkin diagram. We also find all pairs
of isomorphic affine fusion rings.

</DOC>
<DOC>
<DOCNO> 12498 </DOCNO>
Large Stock Market Price Drawdowns Are Outliers


  Drawdowns are essential aspects of risk assessment in investment management.
They offer a more natural measure of real market risks than the variance or
other cumulants of daily (or some other fixed time scale) distributions of
returns. Here, we extend considerably our previous analysis by analyzing the
major financial indices, the major currencies, gold, the twenty largest U.S.
companies in terms of capitalisation as well as nine others chosen randomly. We
find for the major financial markets that approximately 98% of the
distributions of drawdowns is well-represented by a stretched exponential while
the largest drawdowns are occurring with a significantly larger rate than
predicted by the stretched exponential: the largest drops thus constitute
genuine outliers. This is confirmed by extensive testing on surrogate data,
which unambiguously show that large stock market drops (and crashes) cannot be
accounted for by the distribution of returns characterising the smaller market
moves. They thus belong to a different class of their own and call for a
specific amplification mechanism. A similar scenario is found for the majority
of the company stocks analysed. Drawups exhibit a similar behavior in only
about half the markets that we examined. In the spirit of Bacon in Novum
Organum about 400 years ago, ``Errors of Nature, Sports and Monsters correct
the understanding in regard to ordinary things, and reveal general forms. For
whoever knows the ways of Nature will more easily notice her deviations; and,
on the other hand, whoever knows her deviations will more accurately describe
her ways,'' we propose that outliers reveal fundamental properties of the stock
market.

</DOC>
<DOC>
<DOCNO> 84115 </DOCNO>
Analitical approximation of $<\phi^2>$ for a massive scalar field in


  An analitical approximation of $<\phi^2>$ for a massive scalar field in a
zero temperature vacuum state in static spherically symmetric spacetimes is
obtained. The calculations are based on the method for computing vacuum
expectations values for scalar fields in general static spherically symmetric
spacetimes derived by Anderson, Hiscock and Samuel [Phys. Rev. D {\bf 51}, 4337
(1995)]. The analitical approximation is used to compute $<\phi^2>$ in
Schwarzschild and wormhole spacetimes.

</DOC>
<DOC>
<DOCNO> 69366 </DOCNO>
Four-Fermion Production in Electron-Positron Collisions


  This report summarises the results of the four-fermion working group of the
LEP2-MC workshop, held at CERN from 1999 to 2000. Recent developments in the
calculation of four-fermion processes in electron-positron collisions at LEP-2
centre-of-mass energies are presented, concentrating on predictions for four
main reactions: W-pair production, visible photons in four-fermion events,
single-W production and Z-pair production. Based on a comparison of results
derived within different approaches, theoretical uncertainties on these
predictions are established.

</DOC>
<DOC>
<DOCNO> 71473 </DOCNO>
Gravitational Excitons as Dark Matter


  In earlier work it was pointed out that for warped product spacetimes the
conformal (geometrical moduli) excitations of the internal compactified factor
spaces should be observable as massive scalar fields in the external spacetime.
Here we show that these scalar fields (gravitational excitons) describe weakly
interacting particles and can be considered as dark matter component. Masses of
the gravexcitons are defined by the form of the effective potential of the
theory and the stabilization scales of the internal space. This implies that
different stabilization scales result in different types of DM. An essential
role is played by the effective potential. On the one hand, its minima fix
possible stabilization scales of the internal spaces; on the other hand, they
provide possible values for the effective cosmological constant.

</DOC>
<DOC>
<DOCNO> 151478 </DOCNO>
Time-Delay at Higher Genus in High-Energy Open String Scattering


  We explore some aspects of causal time-delay in open string scattering
studied recently by Seiberg, Susskind and Toumbas. By examining high-energy
scattering amplitudes at higher order in perturbation theory, we argue that
causal time-delay at G-th order is 1/(G+1) times smaller than the time-delay at
tree level. We propose a space-time interpretation of the result by utilizing
the picture of the high-energy open string scattering put forward by Gross and
Manes. We argue that the phenomenon of reduced time-delay is attributed to the
universal feature of the space-time string trajectory in high-energy scattering
that string shape at higher order remains the same as that at tree level but
overall scale is reduced. We also discuss implications to the space-time
uncertainty principle and make brief comments on causal time-delay behavior in
space/time noncommutative field theory.

</DOC>
<DOC>
<DOCNO> 40633 </DOCNO>
Study of conversion decays phi->etae+e-, eta->e+e-g and eta->pi+pi-e+e-


  Using 15.1 pb^{-1} of data collected by CMD-2 in the phi-meson energy range,
the branching ratios of the following conversion decays have been measured:
B(\phi\to\eta e^+e^-) = (1.14\pm0.10\pm0.06)\cdot10^{-4}, B(\eta\to
e^+e^-\gamma) = (7.10\pm0.64\pm0.46)\cdot10^{-3}, B(\eta\to\pi^+\pi^-e^+e^-) =
(3.7^{+2.5}_{-1.8}\pm0.3)\cdot10^{-4}. The upper limits for the following rare
conversion decays have been obtained at the 90% confidence level:
B(\phi\to\eta\mu^+\mu^-) < 9.4\cdot10^{-6}, B(\eta\to e^+e^-e^+e^-) <
6.9\cdot10^{-5}.

</DOC>
<DOC>
<DOCNO> 11365 </DOCNO>
Non-Deterministic Learning Dynamics in Large Neural Networks due to


  We study the dynamics of on-line learning in large perceptrons, for the case
of training sets with a structural bias of the input vectors, by deriving exact
and closed macroscopic dynamical laws using non-equilibrium statistical
mechanical tools. In sharp contrast to the more conventional theories developed
for homogeneously distributed or only weakly biased data, these laws are found
to describe a non-trivial and persistently non-deterministic macroscopic
evolution, and a generalisation error which retains both stochastic and
sample-to-sample fluctuations, even for infinitely large networks. Furthermore,
for the standard error-correcting microscopic algorithms (such as the
perceptron learning rule) one obtains learning curves with distinct
bias-induced phases. Our theoretical predictions find excellent confirmation in
numerical simulations.

</DOC>
<DOC>
<DOCNO> 84572 </DOCNO>
Generic Tracking of Multiple Apparent Horizons with Level Flow


  We report the development of the first apparent horizon locator capable of
finding multiple apparent horizons in a ``generic'' numerical black hole
spacetime. We use a level-flow method which, starting from a single arbitrary
initial trial surface, can undergo topology changes as it flows towards
disjoint apparent horizons if they are present. The level flow method has two
advantages: 1) The solution is independent of changes in the initial guess and
2) The solution can have multiple components. We illustrate our method of
locating apparent horizons by tracking horizon components in a short
Kerr-Schild binary black hole grazing collision.

</DOC>
<DOC>
<DOCNO> 40528 </DOCNO>
Search for Supersymmetric Particles in e+e- Collisions at sqrt(s) up to


  Searches for pair production of squarks, sleptons, charginos, and neutralinos
are performed with the data collected by the ALEPH detector at LEP at
centre-of-mass energies from 188.6 to 201.6 GeV. No evidence for any such
signals is observed in a total integrated luminosity of about 410pb-1. The
negative results of the searches are translated into exclusion domains in the
space of the relevant MSSM parameters, which improve significantly on the
constraints set previously. Under the assumptions of gaugino and sfermion mass
unification, these results allow a 95% C.L. lower limit of 37GeV/c2 to be set
on the mass of the lightest neutralino for any tan beta and sfermion mass.
Additional constraints in the MSSM parameter space are derived from the
negative results of ALEPH searches for Higgs bosons. The results are also
interpreted in the framework of minimal supergravity.

</DOC>
<DOC>
<DOCNO> 39994 </DOCNO>
Hadronic Structure Functions of the Photon Measured at LEP


  The measurements of hadronic structure functions of the photon based on the
reaction ee --> ee gamma^(*)(P^2) gamma^*(Q^2)--> ee hadrons are discussed.

</DOC>
<DOC>
<DOCNO> 10528 </DOCNO>
Coherent dipolar correlations in the ground-state of Kagome frustrated


  We propose a new model for the nature of the low temperature phase of a
geometrically frustrated antiferromgnet (AFM) with a Kagome lattice,
SrCr$_{8-x}$Ga$_{4+x}$O$_{19}$. We propose that the long-range dipolar
interaction between the magnetic Cr$^{3+}$ ions introduces correlations in
their dynamics. The dipolar ground-state has the spins performing correlated
zero-point oscillations in a coherent state with a well defined global phase
and a complex order-parameter (i.e. Off-Diagonal Long Range Order). We
calculate the magnon excitations of such a dipolar array and we find good
agreement with the spin-wave velocities infered from measurements of the
specific-heat. Various experimental properties of these materials are naturally
explained by such a model.

</DOC>
<DOC>
<DOCNO> 85045 </DOCNO>
Response to Fackerell's Article


  E. D. Fackerell claims: 1) that Alley and Yilmaz treatment of parallel slabs
in general relativity is wrong because the Yilmaz metric used is not a solution
of the field equations of general relativity; 2) he also claims that the
correct treatment of the parallel slab problem in general relativity must be
based on the so-called Taub metric. We show below that both of Fackerell's
claims are false. His first claim is based on his failure to distinguish the
matter-free regions and the regions with matter. His second claim is based on
his failure to recognize that for the Taub metric the left-hand side, hence
also the right-hand side of the field equations, are identically zero
everywhere. Thus no material systems can be treated via the Taub metric.

</DOC>
<DOC>
<DOCNO> 118262 </DOCNO>
Eclipse maps of spiral shocks in the accretion disc of IP Pegasi in


  Eclipse lightcurves of the dwarf nova IP Peg during the November 1996
outburst are analysed with eclipse mapping techniques to constrain the location
and investigate the spatial structure of the spiral shocks observed in the
Doppler tomograms (Harlaftis et al. 1999). Eclipse maps in the blue continuum
and in the CIII+NIII 4650 emission line show two asymmetric arcs of \sim 90
degrees in azimuth and extending from intermediate to the outer disc regions (R
\simeq 0.2 - 0.6 R_{L1}, where R_{L1} is the distance from disc centre to the
inner Lagrangian point) which are interpreted as being the spiral shocks seen
in the Doppler tomograms. The HeII 4686 eclipse map also shows two asymmetric
arcs diluted by a central brightness source. The central source probably
corresponds to the low-velocity component seen in the Doppler tomogram and is
understood in terms of gas outflow in a wind emanating from the inner parts of
the disc. We estimate that the spirals contribute about 16 and 30 per cent of
the total line flux, respectively, for the HeII and CIII+NIII lines. Comparison
between the Doppler and eclipse maps reveal that the Keplerian velocities
derived from the radial position of the shocks are systematically larger than
those inferred from the Doppler tomography indicating that the gas in the
spiral shocks has sub-Keplerian velocities. We undertake simulations with the
aim to investigate the effect of artifacts on the image reconstruction of the
spiral structures.

</DOC>
<DOC>
<DOCNO> 10565 </DOCNO>
Coherence properties of a continuous atom laser


  We investigate the coherence properties of an atomic beam evaporatively
cooled in a magnetic guide, assuming thermal equilibrium in the quantum
degenerate regime. The gas experiences two-dimensional, transverse
Bose-Einstein condensation rather than a full three-dimensional condensation
because of the very elongated geometry of the magnetic guide. First order and
second order correlation functions of the atomic field are used to characterize
the coherence properties of the gas along the axis of the guide. The coherence
length of the gas is found to be much larger than the thermal de Broglie
wavelength in the strongly quantum degenerate regime. Large intensity
fluctuations present in the ideal Bose gas model are found to be strongly
reduced by repulsive atomic interactions; this conclusion is obtained with a
one-dimensional classical field approximation valid when the temperature of the
gas is much higher than its chemical potential, k_B T >> |mu|.

</DOC>
<DOC>
<DOCNO> 102599 </DOCNO>
On indecomposable modules over the Virasoro algebra


  It is proved that an indecomposable Harish-Chandra module over the Virasoro
algebra must be (i) a uniformly bounded module, or (ii) a module in Category
$\cal O$, or (iii) a module in Category ${\cal O}^-$, or (iv) a module which
contains the trivial module as one of its composition factors.

</DOC>
<DOC>
<DOCNO> 39699 </DOCNO>
Assessment and Outlook


  My assignment at this conference is to assess where we are in high-energy
physics and speculate on where we might be going. This frees me from any
obligation to summarize all that went on here and allows me to talk just about
those topics that interest me the most at this time. I will let my prejudices
show and talk a bit about physics in general, CP violation, neutrinos,
accelerators, non-accelerator experiments, and even theory.

</DOC>
<DOC>
<DOCNO> 100133 </DOCNO>
Central Binomial Sums, Multiple Clausen Values and Zeta Values


  We find and prove relationships between Riemann zeta values and central
binomial sums. We also investigate alternating binomial sums (also called
Ap\'ery sums). The study of non-alternating sums leads to an investigation of
different types of sums which we call multiple Clausen values. The study of
alternating sums leads to a tower of experimental results involving
polylogarithms in the golden ratio. In the non-alternating case, there is a
strong connection to polylogarithms of the sixth root of unity, encountered in
the 3-loop Feynman diagrams of {\tt hep-th/9803091} and subsequently in
hep-ph/9910223, hep-ph/9910224, cond-mat/9911452 and hep-th/0004010.

</DOC>
<DOC>
<DOCNO> 117370 </DOCNO>
Non-Thermal Emission from Relativistic Electrons in Clusters of


  We have investigated evolution of non-thermal emission from relativistic
electrons accelerated at around the shock fronts during merger of clusters of
galaxies. We estimate synchrotron radio emission and inverse Compton scattering
of cosmic microwave background photons from extreme ultraviolet (EUV) to hard
X-ray range. The hard X-ray emission is most luminous in the later stage of
merger. Both hard X-ray and radio emissions are luminous only while signatures
of merging events are clearly seen in thermal intracluster medium (ICM). On the
other hand, EUV radiation is still luminous after the system has relaxed.
Propagation of shock waves and bulk-flow motion of ICM play crucial roles to
extend radio halos. In the contracting phase, radio halos are located at the
hot region of ICM, or between two substructures. In the expanding phase, on the
other hand, radio halos are located between two ICM hot regions and shows
rather diffuse distribution.

</DOC>
<DOC>
<DOCNO> 123177 </DOCNO>
A revised Cepheid distance to NGC 4258 and a test of the distance scale


  In a previous paper (Maoz et al. 1999), we reported a Hubble Space Telescope
(HST) Cepheid distance to the galaxy NGC 4258 obtained using the calibrations
and methods then standard for the Key Project on the Extragalactic Distance
Scale. Here, we reevaluate the Cepheid distance using the revised Key Project
procedures described in Freedman et al. (2001). These revisions alter the zero
points and slopes of the Cepheid Period-Luminosity (P-L) relations derived at
the Large Magellanic Cloud (LMC), the calibration of the HST WFPC2 camera, and
the treatment of metallicity differences. We also provide herein full
information on the Cepheids described in Maoz et al. 1999. Using the refined
Key Project techniques and calibrations, we determine the distance modulus of
NGC 4258 to be 29.47 +/- 0.09 mag (unique to this determination) +/- 0.15 mag
(systematic uncertainties in Key Project distances), corresponding to a metric
distance of 7.8 +/- 0.3 +/- 0.5 Mpc and 1.2 sigma from the maser distance of
7.2 +/- 0.5 Mpc. We also test the alternative Cepheid P-L relations of Feast
(1999), which yield more discrepant results. Additionally, we place weak limits
upon the distance to the LMC and upon the effect of metallicity in Cepheid
distance determinations.

</DOC>
<DOC>
<DOCNO> 174586 </DOCNO>
First experimental results on creation and decay of eta-mesic nuclei


  First experimental results on photoproduction of eta-mesic nuclei are
analyzed. In an experiment performed at the 1 GeV electron synchrotron of the
Lebedev Physical Institute, correlated (pi+,n) pairs arising from the reaction
\gamma + C12 -> N + (A-1)_eta -> N + (pi+,n) + (A-2) and flying transversely to
the photon beam have been observed. When the photon energy exceeds the
eta-meson production threshold, a distribution of the (pi+,n) pairs over their
total energy is found to have a peak in the subthreshold region of the
internal-conversion process eta p -> pi+ n which signals about formation of
eta-mesic nuclei.

</DOC>
<DOC>
<DOCNO> 118995 </DOCNO>
Photon acceleration in variable ultra-relativistic outflows and


  MeV seed photons produced in shocks in a variable ultra-relativistic outflow
gain energy by the Fermi mechanism, because the photons Compton scatter off
relativistically colliding shells. The Fermi-modified high-energy photon
spectrum has a non-universal slope and a universal cutoff. A significant
increase in the total radiative efficiency is possible. In some gamma ray
bursts, most of the power might be emitted at the high-energy cutoff for this
mechanism, which would be close to 100 MeV for outflows with a mean bulk
Lorentz factor of 100.

</DOC>
<DOC>
<DOCNO> 13941 </DOCNO>
Off-axis vortices in trapped Bose condensed gases: angular momentum and


  We consider non centered vortices and their arrays in a cylindrically trapped
Bose-Einstein condensate at zero temperature. We study the kinetic energy and
the angular momentum per particle in the Thomas Fermi regime and their
dependence on the distance of the vortices from the center of the trap. Using a
perturbative approach with respect to the velocity-field of the vortices, we
calculate to first order the frequency shift of the collective low-lying
excitations due to the presence of an off-center vortex or a vortex array, and
compare these results with predictions which would be obtained by the
application of a simple sum-rule approach, previously found to be very
successful for centered vortices. It turns out that the simple sum-rule
approach fails for off-centered vortices.

</DOC>
<DOC>
<DOCNO> 100414 </DOCNO>
On Jordan angles and triangle inequality in Grassmannian


  We obtain the following version of Lidskii theorem. Let L, M, N be
p-dimensional subspaces in R^n. Let \psi_j be the angles between L and M, let
\phi_j be the angles between M and N, and let \theta_j be the angles between L
and N. Consider the orbit of the vector \psi with respect to permutations of
coordinates and inversions of axises. Let Z be the convex hull of this orbit.
Then \theta is an element of the polyhedron \phi + Z. We discuss similar
theorems for other symmetric spaces. We obtain formula for geodesic distance
for any invariant Finsler metrics on a classical Riemannian symmetric space.

</DOC>
<DOC>
<DOCNO> 101206 </DOCNO>
The chiral WZNW phase space as a quasi-Poisson space


  It is explained that the chiral WZNW phase space is a quasi-Poisson space
with respect to the `canonical' Lie quasi-bialgebra which is the classical
limit of Drinfeld's quasi-Hopf deformation of the universal enveloping algebra.
This exemplifies the notion of quasi-Poisson-Lie symmetry introduced recently
by Alekseev and Kosmann-Schwarzbach, and also permits us to generalize certain
dynamical twists considered previously in this example.

</DOC>
<DOC>
<DOCNO> 118207 </DOCNO>
Eccentric Orbits of close Companions to Asymptotic Giant Branch Stars


  I propose that the relatively high eccentricity found in some tidally
strongly interacting binary systems, where the mass-losing star is an evolved
giant star, e.g., an asymptotic giant branch star, is caused by an enhanced
mass loss rate during periastron passages. Tidal interaction by itself will
circularize the orbits of these systems in a relatively short time, hence a
mechanism which increases the eccentricity on a shorter time scale is required.
The proposed scenario predicts that the nebula formed by the mass loss process
possesses a prominent departure from axisymmetrical structure. Such a departure
is observed in the Red Rectangle, which has a central binary system, HD 44179,
with an orbital period of 318 days, and an eccentricity of e=0.38.

</DOC>
<DOC>
<DOCNO> 101247 </DOCNO>
Jet Schemes of Locally Complete Intersection Canonical Singularities


  We prove that if X is a locally complete intersection variety, then X has all
the jet schemes irreducible if and only if X has canonical singularities. After
embedding X in a smooth variety Y, we use motivic integration to express the
condition that X has irreducible jet schemes in terms of data coming from an
embedded resolution of X in Y. We show that this condition is equivalent with
having canonical singularities. In the appendix, this result is used to prove a
generalization of Kostant's freeness theorem to the setting of jet schemes.

</DOC>
<DOC>
<DOCNO> 70824 </DOCNO>
Strange Pathways for Black Hole Formation


  Immediately after they are born, neutron stars are characterized by an
entropy per baryon of order unity and by the presence of trapped neutrinos. If
the only hadrons in the star are nucleons, these effects slightly reduce the
maximum mass relative to cold, catalyzed matter. However, if stangeness-bearing
hyperons, a kaon condensate, or quarks are also present, these effects result
in an increase in the maximum mass of up to $\sim 0.3{\rm M}_{\odot}$ compared
to that of a cold, neutrino-free star. This makes a sufficiently massive
proto-neutron star metastable, so that after a delay of 10--100 seconds, the
PNS collapses into a black hole. Such an event might be straightforward to
observe as an abrupt cessation of neutrinos when the instability is triggered.

</DOC>
<DOC>
<DOCNO> 99771 </DOCNO>
Almost holomorphic embeddings in Grassmannians with applications to


  We use Donaldson's approximately holomorphic techniques to build embeddings
of a closed symplectic manifold with symplectic form of integer class in the
grassmannians Gr(r,N). We assure that these embeddings are asymptotically
holomorphic in a precise sense. We study first the particular case of
embeddings in the projective space $CP^N$ obtaining control on N. The main
reason of our study is the construction of singular determinantal submanifolds
as the intersection of the embedding with certain ``generalized Schur cycles''
defined on a product of grassmannians. It is shown that the symplectic type of
these submanifolds is quite more general that the ones obtained by Auroux as
zero sets of approximately holomorphic sections of ``very ample'' vector
bundles.

</DOC>
<DOC>
<DOCNO> 100510 </DOCNO>
From planar graphs to embedded graphs - a new approach to Kauffman and


  In \cite{4} Kauffman and Vogel constructed a rigid vertex regular isotopy
invariant for unoriented four-valent graphs embedded in three dimensional
space. It assigns to each embedded graph $G$ a polynomial, denoted $[G]$, in
three variables, $A$, $B$ and $a$, satisfies the skein relation: $$
[\psdiag{2}{6}{overcross}]=A [\psdiag{2}{6}{horlines}]+B
[\psdiag{2}{6}{verlines}]+[\psdiag{2}{6}{vertex}]$$ and is defined in terms of
a state-sum and the Dubrovnik polynomial for links. Using the graphical
calculus of \cite{4} it is shown that the polynomial of a planar graph can be
calculated recursively from that of planar graphs with less vertices, which
also allows the polynomial of an embedded graph to be calculated without
resorting to links. The same approach is used to give a direct proof of
uniqueness of the (normalized) polynomial restricted to planar graphs. In the
case $B=A^{-1}$ and $a=A$, it is proved that for a planar graph $G$ we have
$[G]=2^{c-1}(-A-A^{-1})^v $, where $c$ is the number of connected components of
$G$ and $v$ is the number of vertices of $G$. As a corollary, a necessary, but
not sufficient, condition is obtained for an embedded graph to be ambient
isotopic to a planar graph.

</DOC>
<DOC>
<DOCNO> 13380 </DOCNO>
"Young" soap films


  If we pull out rapidly a metallic frame out of a surfactant solution, we
arrive at a "young" soap film with relatively simple features, as noticed first
by Lucassen. The weight of the film is equilibrated by a vertical gradient of
surface tension. At each level, the local solution concentration equilibrates
with the local monolayers. A detailed analysis of the young films was started
by us in 1987. We present here an approach which is more illuminating a) the
concentration profiles decay exponentially at large heights, with a
characteristic length in the range of meters b) the surface is protected up to
a different (larger) height c) we also review the dynamic requirements. The
surfactant must reach the surface in a time shorter than the free fall time of
a pure water film.

</DOC>
<DOC>
<DOCNO> 85292 </DOCNO>
Cosmic crystallography: the hyperbolic isometries


  All orientation preserving isometries of the hyperbolic three-space are
studied, and the probability density of conjugate pair separations for each
isometry is presented. The study is relevant for the cosmic crystallography,
and is the theoretical counterpart of the mean histograms arising from computer
simulations of the isometries.

</DOC>
<DOC>
<DOCNO> 170505 </DOCNO>
Geometric Phase of Three-level Systems in Interferometry


  We present the first scheme for producing and measuring an Abelian geometric
phase shift in a three-level system where states are invariant under a
non-Abelian group. In contrast to existing experiments and proposals for
experiments, based on U(1)-invariant states, our scheme geodesically evolves
U(2)-invariant states in a four-dimensional SU(3)/U(2) space and is physically
realized via a three-channel optical interferometer.

</DOC>
<DOC>
<DOCNO> 9432 </DOCNO>
Phonon-Induced Renormalization and Interaction: An Improvement on


  Starting from the Flohlich electron-phonon model, which has a history of 50
years, a new unitary transformation is proposed to implement the perturbation
treatment. Our main results are: (1)The phonon-induced interaction shows a
crossover from the BCS-like potential when the phonon frequency $\omega_p$ is
much smaller than the Fermi energy $E_F$ to that of the small polarons when
$\omega_p/E_F\ge 1$. (2)The jump of momentum distribution of electron number
$n_{\bf k}$ at the Fermi surface goes to zero when the dimensionless coupling
constant $\lambda$ increases to the critical value $\lambda_c\ge 1$, which
means a possible broken down of the Fermi-liquid description.

</DOC>
<DOC>
<DOCNO> 178432 </DOCNO>
Light-particle emission from the fissioning nuclei 126Ba, 188Pt and


  We present a comparison of our model treating fission dynamics in conjunction
with light-particle (n, p, alpha) evaporation with the available experimental
data for the nuclei 126Ba, 188Pt and three isotopes of the element Z=110. The
dynamics of the symmetric fission process is described through the solution of
a classical Langevin equation for a single collective variable characterizing
the nuclear deformation along the fission path. A microscopic approach is used
to evaluate the emission rates for pre-fission light particles.
Entrance-channel effects are taken into account by generating an initial spin
distribution of the compound nucleus formed by the fusion of two deformed
nuclei with different relative orientations.

</DOC>
<DOC>
<DOCNO> 67771 </DOCNO>
How to calculate the quantum part of the truly nonperturbative


  Using the effective potential approach for composite operators, we have
formulated a general method how to calculate the truly nonperturbative vacuum
energy density in the axial gauge QCD quantum models of its ground state. It is
defined as integrated out the truly nonperturbative part of the full gluon
propagator over the deep infrared region (soft momentum region). The nontrivial
minimization procedure makes it possible to determine the value of the soft
cutoff in terms of the corresponding nonperturbative scale parameter which is
inevitably presented in any nonperturbative model for the full gluon
propagator. If the chosen Ansatz for the full gluon propagator is a realistic
one, then our method uniquely determines the truly vacuum energy density, which
is always finite, automatically negative and it has no imaginary part (stable
vacuum). We illustrate it by considering the Abelian Higgs model of dual QCD
ground state. We have explicitly shown that the vacuum of this model without
string contributions is unstable against quantum corrections.

</DOC>
<DOC>
<DOCNO> 80682 </DOCNO>
A test of the Kugo-Ojima confinement criterion by lattice Landau gauge


  The first test of the Kugo-Ojima colour confinement criterion by the lattice
Landau gauge QCD simulation is performed. The parameter u which is expected to
be -1\delta^a_b in the continuum theory was found to be -0.7\delta^a_b in the
strong coupling region. The data is analyzed in connection with the theory of
Zwanziger. In the weak coupling region, the expectation value of the horizon
function is negative or consistent to 0.

</DOC>
<DOC>
<DOCNO> 10134 </DOCNO>
Non-Perturbative Renormalization Flow in Quantum Field Theory and


  We review the use of an exact renormalization group equation in quantum field
theory and statistical physics. It describes the dependence of the free energy
on an infrared cutoff for the quantum or thermal fluctuations. Non-perturbative
solutions follow from approximations to the general form of the coarse-grained
free energy or effective average action. They interpolate between the
microphysical laws and the complex macroscopic phenomena. Our approach yields a
simple unified description for O(N)-symmetric scalar models in two, three or
four dimensions, covering in particular the critical phenomena for the
second-order phase transitions, including the Kosterlitz-Thouless transition
and the critical behavior of polymer chains. We compute the aspects of the
critical equation of state which are universal for a large variety of physical
systems and establish a direct connection between microphysical and critical
quantities for a liquid-gas transition. Universal features of first-order phase
transitions are studied in the context of scalar matrix models. We show that
the quantitative treatment of coarse graining is essential for a detailed
estimate of the nucleation rate. We discuss quantum statistics in thermal
equilibrium or thermal quantum field theory with fermions and bosons and we
describe the high temperature symmetry restoration in quantum field theories
with spontaneous symmetry breaking. In particular, we explore chiral symmetry
breaking and the high temperature or high density chiral phase transition in
quantum chromodynamics using models with effective four-fermion interactions.

</DOC>
<DOC>
<DOCNO> 152592 </DOCNO>
Open and Unoriented Strings from Topological Membrane - I. Prolegomena


  We study open and unoriented strings in a Topological Membrane (TM) theory
through orbifolds of the bulk 3D space. This is achieved by gauging discrete
symmetries of the theory. Open and unoriented strings can be obtained from all
possible realizations of $C$, $P$ and $T$ symmetries. The important role of $C$
symmetry to distinguish between Dirichlet and Neumman boundary conditions is
discussed in detail.

</DOC>
<DOC>
<DOCNO> 8312 </DOCNO>
Spin- and charge-density oscillations in spin chains and quantum wires


  We analyze the spin- and charge-density oscillations near impurities in spin
chains and quantum wires. These so-called Friedel oscillations give detailed
information about the impurity and also about the interactions in the system.
The temperature dependence of these oscillations explicitly shows the
renormalization of backscattering and conductivity, which we analyze for a
number of different impurity models. We are also able to analyze screening
effects in one dimension. The relation to the Kondo effect and experimental
consequences are discussed.

</DOC>
<DOC>
<DOCNO> 119912 </DOCNO>
5@5 - a 5 GeV energy threshold array of imaging atmospheric Cherenkov


  We discuss the concept and the performance of a powerful future ground-based
astronomical instrument - a stereoscopic array of several large imaging
atmospheric Cherenkov telescopes installed at a very high mountain elevation of
about 5 km a.s.l. or more - for the study of the gamma-ray sky at energies from
several GeV to 100 GeV.

</DOC>
<DOC>
<DOCNO> 150683 </DOCNO>
A note on R-currents and trace anomalies in the (2,0) tensor multiplet


  We discuss the two- and three-point functions of the SO(5) R-current of the
(2,0) tensor multiplet in d=6, using AdS/CFT correspondence as well as a free
field realization. The results obtained via AdS/CFT correspondence coincide
with the ones from a free field calculation up to an overall 4N^3 factor. This
is the same factor found recently in studies of the two- and three-point
functions of the energy momentum tensor in the (2,0) theory. We also connect
our results to the trace anomaly in d=6 in the presence of external vector
fields and briefly discuss their implications.

</DOC>
<DOC>
<DOCNO> 68422 </DOCNO>
On the choice of colliding beams to study deformation effects in


  It has been suggested that collisions between deformed shapes will lead to
interesting effects on various observables such as K production and elliptic
flow. Simple formulae can be written down which show how to choose the
colliding beams which will maximise the effects of deformation.

</DOC>
<DOC>
<DOCNO> 174512 </DOCNO>
A consistent analysis of (e,e'p) and (d,3He) experiments


  The apparent discrepancy between spectroscopic factors obtained in (e,e'p)
and (d,3He) experiments is investigated. This is performed first for
48Ca(e,e'p) and 48Ca(d,3He) experiments and then for other nuclei. It is shown
that the discrepancy disappears if the (d,3He) experiments are re-analyzed with
a non-local finite range DWBA analysis with a bound-state wave function that is
obtained from (e,e'p) experiments.

</DOC>
<DOC>
<DOCNO> 119309 </DOCNO>
Constraints on Particle Acceleration from the Diffuse Isotropic


  Gamma rays trace accelerated particles, and the observed flux of
extragalactic gamma rays therefore constrains the global efficiency for
particle acceleration. Extragalactic jets in active galactic nuclei can account
for the gamma ray background if their particle acceleration efficiency
considerably exceeds ~ 18 per cent which would imply that particle acceleration
is an essential part of the thermodynamics in these sources.

</DOC>
<DOC>
<DOCNO> 118806 </DOCNO>
The longest thermonuclear X-ray burst ever observed? (A BeppoSAX Wide


  A long flux enhancement, with an exponential decay time of 86 min, is
detected in 4U 1735-44 with the BeppoSAX Wide Field Cameras. We argue that this
is a type-I X-ray burst, making it the longest such burst ever observed.
Current theories for thermonuclear bursts predict shorter and more frequent
bursts for the observed persistent accretion rate.

</DOC>
<DOC>
<DOCNO> 121675 </DOCNO>
HI Observations of Giant Low Surface Brightness Galaxies


  We have used the Nancay Radio Telescope to obtain new global HI data for 16
giant low surface brightness (LSB) galaxies. Our targets have optical
luminosities and disk scale lengths at the high end for spiral galaxies
(L_B~10^10 Lsun and h_r>~6 kpc for H_0=75 km/s/Mpc), but they have diffuse
stellar disks, with mean disk surface brightnesses ~1 magnitude or more fainter
than normal giant spirals. Thirteen of the galaxies previously had been
detected in HI by other workers, but the published HI observations were either
confused, resolved by the telescope beam, of low signal-to-noise, or showed
significant discrepancies between different authors. For the other 3 galaxies,
no HI data were previously available. Several of the galaxies were resolved by
the Nancay 3.6' E-W beam, so global parameters were derived from multiple-point
mapping observations. Typical HI masses for our sample are ~10^10 Msun, with
M_HI/L_B=0.3-1.7 (in solar units). All of the observed galaxies have published
optical surface photometry, and we have compiled key optical measurements for
these objects from the literature. We frequently find significant variations
among physical parameters of giant LSB galaxies reported by various workers.

</DOC>
<DOC>
<DOCNO> 178686 </DOCNO>
Perspectives of scalar- and vector-meson production in hadron-nucleus


  The production and decay of vector mesons ($\rho, \omega$) in $pA$ reactions
at COSY energies is studied with particular emphasis on their in-medium
spectral functions. It is explored within transport calculations, if hadronic
in-medium decays like $\pi^+\pi^-$ or $\pi^0 \gamma$ might provide
complementary information to their dilepton ($e^+e^-$) decays. Whereas the
$\pi^+ \pi^-$ signal from the $\rho$-meson is found to be strongly distorted by
pion rescattering, the $\omega$-meson Dalitz decay to $\pi^0 \gamma$ appears
promising even for more heavy nuclei. The perspectives of scalar meson ($f_0,
a_0$) production in $pp$ reactions are investigated within a boson-exchange
model indicating that the $f_0$-meson might hardly be detected in these
collisions in the $K \bar{K}$ or $\pi \pi$ decay channels whereas the exclusive
channel $pp \to d a_0^+$ looks very promising.

</DOC>
<DOC>
<DOCNO> 118003 </DOCNO>
Winds from accretion disks driven by the radiation and


  We study the 2-D, time-dependent hydrodynamics of radiation-driven winds from
luminous accretion disks threaded by a strong, large-scale, ordered magnetic
field. The radiation force is due to spectral lines and is calculated using a
generalized multidimensional formulation of the Sobolev approximation. The
effects of the magnetic field are approximated by adding a force that emulates
a magnetocentrifugal force. Our approach allows us to calculate disk winds when
the magnetic field controls the flow geometry, forces the flow to corotate with
the disk, or both. In particular, we calculate models where the lines of the
poloidal component of the field are straight and inclined to the disk at a
fixed angle. Our numerical calculations show that flows which corotate with the
disk have a larger mass loss rate than their counterparts which conserve
specific angular momentum. The difference in the mass loss rate between these
two types of winds can be several orders of magnitude for low disk luminosities
but vanishes for high disk luminosities. Winds which corotate with the disk
have much higher velocities than angular momentum conserving winds. Fixing the
wind geometry stabilizes winds which are unsteady when the geometry is derived
self-consistently. The inclination angle between the poloidal velocity and the
normal to the disk midplane is important. Non-zero inclination angles allow the
magnetocentrifugal force to increase the mass loss rate for low luminosities,
and increase the wind velocity for all luminosities. Our calculations also show
that the radiation force can launch winds from magnetized disks. The line force
can be essential in producing MHD winds from disks where the thermal energy is
too low to launch winds or where the field lines make an angle of < 30^o with
respect to the normal to the disk.

</DOC>
<DOC>
<DOCNO> 169720 </DOCNO>
Quantum Tomography Via Group Theory


  Amongst the multitude of state reconstruction techniques, the so-called
"quantum tomography" seems to be the most fruitful. In this letter, I will
start by developing the mathematical apparatus of quantum tomography and,
later, I will explain how it can be applied to various quantum systems.

</DOC>
<DOC>
<DOCNO> 71455 </DOCNO>
Soft diffraction at the LHC and properties of the Pomeron


  We briefly describe a model for soft diffraction. The model description of
ISR, SppbarS and Tevatron data, and the predictions of the total, elastic,
single and double diffractive cross sections at the LHC can be found in the
original paper. Here we address issues raised at Diffraction 2000, in
particular concerning the nature of the resulting Pomeron trajectory.

</DOC>
<DOC>
<DOCNO> 118375 </DOCNO>
On the helium content of Galactic globular clusters via the R parameter


  We estimate the empirical R parameter in 26 Galactic Globular Clusters
covering a wide metallicity range, imaged by WFPC2 on board the HST. The
improved spatial resolution permits a large fraction of the evolved stars to be
measured and permits accurate assessment of radial populaton gradients and
completeness corrections. In order to evaluate both the He abundance and the He
to metal enrichment ratio, we construct a large set of evolutionary models by
adopting similar metallicities and different He contents. We find an absolute
He abundance which is lower than that estimated from spectroscopic measurements
in HII regions and from primordial nucleosynthesis models. This discrepancy
could be removed by adopting a C12O16 nuclear cross section about a factor of
two smaller than the canonical value, although also different assumptions for
mixing processes can introduce systematical effects. The trend in the R
parameter toward solar metallicity is consistent with an upper limit to the He
to metal enrichment ratio of the order of 2.5.

</DOC>
<DOC>
<DOCNO> 151097 </DOCNO>
Anti-Periodic Boundary Conditions in Supersymmetric DLCQ


  It is of considerable importance to have a numerical method for solving
supersymmetric theories that can support a non-zero central charge. The central
charge in supersymmetric theories is in general a boundary integral and
therefore vanishes when one uses periodic boundary conditions. One is therefore
prevented from studying BPS states in the standard supersymmetric formulation
of DLCQ (SDLCQ). We present a novel formulation of SDLCQ where the fields
satisfy anti-periodic boundary conditions. The Hamiltonian is written as the
anti-commutator of two charges, as in SDLCQ. The anti-periodic SDLCQ we
consider breaks supersymmetry at finite resolution, but requires no
renormalization and becomes supersymmetric in the continuum limit. In
principle, this method could be used to study BPS states. However, we find its
convergence to be disappointingly slow.

</DOC>
<DOC>
<DOCNO> 11218 </DOCNO>
Chiral order of Spin-1/2 frustrated quantum spin chains


  The ordering of the frustrated S=1/2 XY spin chain with the competing
nearest- and next-nearest-neighbor antiferromagnetic couplings, J_1 and J_2, is
studied by using the density-matrix renormalization-group method. It is found
that besides the well-known spin-fluid and dimer phases the chain exhibits
gapless `chiral' phase characterized by the spontaneous breaking of parity, in
which the long-range order parameter is a chirality, \kappa
_l=S_l^xS_{l+1}^y-S_l^yS_{l+1}^x, whereas the spin correlation decays
algebraically. The dimer phase is realized for 0.33 \lsim j = J_2/J_1 \lsim
1.26 while the chiral phase is realized for j \gsim 1.26.

</DOC>
<DOC>
<DOCNO> 14009 </DOCNO>
Self-duality in Maxwell-Chern-Simons theories with non minimal coupling


  We consider a general class of non-local MCS models whose usual minimal
coupling to a conserved current is supplemented with a (non-minimal) magnetic
Pauli-type coupling. We find that the considered models exhibit a self-duality
whenever the magnetic coupling constant reaches a special value: the partition
function is invariant under a set of transformations among the parameter space
(the duality transformations) while the original action and its dual
counterpart have the same form. The duality transformations have a structure
similar to the one underlying self-duality of the (2+1)-dimensional Zn-abelian
Higgs model with Chern-Simons and bare mass term.

</DOC>
<DOC>
<DOCNO> 151802 </DOCNO>
Fractional Branes and the Entropy of 4D Black Holes


  We reconsider the four dimensional extremal black hole constructed in type
IIB string theory as the bound state of D1-branes, D5-branes, momentum, and
Kaluza-Klein monopoles. Specifically, we examine the case of an arbitrary
number of monopoles. Consequently, the weak coupling calculation of the
microscopic entropy requires a study of the D1-D5 system on an ALE space. We
find that the complete expression for the Bekenstein-Hawking entropy is
obtained by taking into account the massless open strings stretched between the
fractional D-branes which arise in the orbifold limit of the ALE space. The
black hole sector therefore arises as a mixed Higgs-Coulomb branch of an
effective 1+1 dimensional gauge theory.

</DOC>
<DOC>
<DOCNO> 116800 </DOCNO>
Frequency tuning of the whispering gallery modes of silica microspheres


  We have tuned the whispering gallery modes of a fused silica microresonator
over nearly 1 nm at 800 nm, i.e. over 0.5 FSR or 10^6 linewidths of the
resonator. This has been achieved by a new method based on the stretching of a
two-stem microsphere. The devices described below will permit new Cavity-QED
experiments with this high-Q optical resonator when it is desirable to optimize
its coupling to emitters with given transition frequencies. The tuning
capability demonstrated here is compatible with both UHV and low temperature
operation, which should be useful for future experiments with laser cooled
atoms or single quantum dots.

</DOC>
<DOC>
<DOCNO> 150435 </DOCNO>
Some remarks about gauge-invariant Yang-Mills fields


  In order to eliminate gauge variant degrees of freedom we study the way to
introduce gauge invariant fields in pure non-Abelian Yang-Mills theory. Our
approach is based on the use of the gauge-invariant but path-dependent
variables formalism. It is shown that for a special class of paths these fields
coincide with the usual ones in some definite gauges. The interquark potential
is discussed by exploiting the rich structure of the gluonic cloud or dressing
around static fermions.

</DOC>
<DOC>
<DOCNO> 12474 </DOCNO>
The effect of a parallel magnetic field on the Boltzmann conductivity


  Screening of an external random potential by a two dimensional (2D) Fermi
liquid may be strongly dependent on the degree of its polarization. This is
considered as a possible mechanism for the observed strong magnetoresistance of
the 2D electron liquid in the magnetic field parallel to the electron plane. A
Hartree-Fock calculation for the weakly disordered Hubbard model which
qualitatively describes the experiments on the diagonal and the Hall
resisitivity in the finite-temperature metallic state in the high mobility Si
inversion layers is presented.

</DOC>
<DOC>
<DOCNO> 69135 </DOCNO>
The Fate of Cosmic String Zero Modes


  Cosmic strings in realistic particle physics models have fermion zero modes
in the string core. Such zero modes change the underlying cosmology; for
example, the string can carry a current. We consider the stability of fermion
zero modes to interactions with particles in the surrounding plasma. We also
consider cosmological constraints on such theories, particulary those with a
chiral fermion zero mode, such as arises in a class of supersymmetric models.

</DOC>
<DOC>
<DOCNO> 11338 </DOCNO>
Random bond XXZ chains with modulated couplings


  The magnetization behavior of q-periodic antiferromagnetic spin 1/2
Heisenberg chains under uniform magnetic fields is investigated in a background
of disorder exchange distributions. By means of both real space decimation
procedures and numerical diagonalizations in XX chains, it is found that for
binary disorder the magnetization exhibits wide plateaux at values of
1+2(p-1)/q, where p is the disorder strength. In contrast, no spin gaps are
observed in the presence of continuous exchange distributions. We also study
the magnetic susceptibility at low magnetic fields. For odd q-modulations the
susceptibility exhibits a universal singularity, whereas for q even it displays
a non-universal power law behavior depending on the parameters of the
distribution.

</DOC>
<DOC>
<DOCNO> 8544 </DOCNO>
Spin-flux phase in the Kondo lattice model with classical localized


  We provide numerical evidence that a spin-flux phase exists as a ground state
of the Kondo lattice model with classical local spins on a square lattice. This
state manifests itself as a double-Q magnetic order in the classical spins with
spin density at both $(0,\pi)$ and $(\pi,0)$ and further exhibits fermionic
spin currents around an elementary plaquette of the square lattice. We examine
the spin-wave spectrum of this phase. We further discus an extension to a face
centered cubic (FCC) lattice where a spin-flux phase may also exist. On the FCC
lattice the spin-flux phase manifests itself as a triple-Q magnetically ordered
state and may exist in $\gamma$-Mn alloys.

</DOC>
<DOC>
<DOCNO> 40539 </DOCNO>
Inclusive Particle Production at LEP


  New results on inclusive production of Sigma^- and Lambda(1520) and on proton
production in quark and gluon jets are presented. These results are based on 2
million hadronic Z decays collected with the DELPHI detector at LEP. They are
compared with the results of other LEP experiments and with models. It has been
shown that the total production rates of all light-flavour hadrons measured so
far at LEP 1 follow phenomenological laws related to the spin, isospin,
strangeness and mass of the particles. A significant proton enhancement in
gluon jets is observed, indicating that baryon production proceeds directly
from colour objects.

</DOC>
<DOC>
<DOCNO> 85476 </DOCNO>
Cosmological Models with Nonlinearity of Scalar Field Induced by


  The exact solutions of Einstein - Yang - Mills and interacting with SO (3) -
Yang-Mills field nonlinear scalar field equations in a class of spatially
homogeneous cosmological Friedmann models are obtained.

</DOC>
<DOC>
<DOCNO> 120377 </DOCNO>
Experimental simulation of a stellar photon bath by bremsstrahlung: the


  The nucleosynthesis of heavy proton-rich nuclei in a stellar photon bath at
temperatures of the astrophysical $\gamma$-process was investigated where the
photon bath was simulated by the superposition of bremsstrahlung spectra with
different endpoint energies. The method was applied to derive ($\gamma$,n)
cross sections and reaction rates for several platinum isotopes.

</DOC>
<DOC>
<DOCNO> 71475 </DOCNO>
Anomalous magnetic moment of the electron in a medium


  Radiative effects are considered for an electron moving in a medium in the
presence of an external electromagnetic field. Anomalous magnetic moment (AMM)
of the electron in alpha-order is calculated under these conditions in the form
of two-dimensional integral. Behavior of AMM of high energy electron under
influence of multiple scattering in a medium is analyzed. Both mentioned
effects lead to reduction of AMM.

</DOC>
<DOC>
<DOCNO> 70366 </DOCNO>
The Early Mirror Universe: Inflation, Baryogenesis, Nucleosynthesis and


  There can exist a parallel `mirror' world which has the same particle physics
as the observable world and couples the latter only gravitationally. The
nucleosynthesis bounds demand that the mirror sector should have a smaller
temperature than the ordinary one. By this reason its evolution should be
substantially deviated from the standard cosmology as far as the crucial epochs
like baryogenesis, nucleosynthesis etc. are concerned. Starting from an
inflationary scenario which could explain the different initial temperatures of
the two sectors, we study the time history of the early mirror universe. In
particular, we show that in the context of the GUT or electroweak baryogenesis
scenarios, the baryon asymmetry in the mirror world should be larger than in
the observable one and in fact the mirror baryons could provide the dominant
dark matter component of the universe. In addition, analyzing the
nucleosynthesis epoch, we show that the mirror helium abundance should be much
larger than that of ordinary helium. The implications of the mirror baryons
representing a kind of self-interacting dark matter for the large scale
structure formation, the CMB anysotropy, the galactic halo structures,
microlensing, etc. are briefly discussed.

</DOC>
<DOC>
<DOCNO> 117295 </DOCNO>
Atomic Energy Levels with QED and Contribution of the Screened


  We present an introduction to the principles behind atomic energy level
calculations with Quantum Electrodynamics (QED) and the two-time Green's
function method; this method allows one to calculate an effective Hamiltonian
that contains all QED effects and that can be used to predict QED Lamb shifts
of degenerate, quasidegenerate and isolated atomic levels.

</DOC>
<DOC>
<DOCNO> 7874 </DOCNO>
Microscopic self-consistent theory of Josephson junctions including


  We formulate a fully self-consistent, microscopic model to study the
retardation and correlation effects of the barrier within a Josephson junction.
The junction is described by a series of planes, with electronic correlation
included through a local self energy for each plane. We calculate current-phase
relationships for various junctions, which include non-magnetic impurities in
the barrier region, or an interfacial scattering potential. Our results
indicate that the linear response of the supercurrent to phase across the
barrier region is a good, but not exact indicator of the critical current. Our
calculations of the local density of states show the current-carrying Andreev
bound states and their energy evolution with the phase difference across the
junction.
  We calculate the figure of merit for a Josephson junction, which is the
product of the critical current, Ic, and the normal state resistance, R(N), for
junctions with different barrier materials. The normal state resistance is
calculated using the Kubo formula, for a system with zero current flow and no
superconducting order. Semiclassical calculations would predict that these two
quantities are determined by the transmission probabilities of electrons in
such a way that the product is constant for a given superconductor at fixed
temperature. Our self-consistent solutions for different types of barrier
indicate that this is not the case. We suggest some forms of barrier which
could increase the Ic.R(N) product, and hence improve the frequency response of
a Josephson device.

</DOC>
<DOC>
<DOCNO> 11595 </DOCNO>
First order valence transition in YbInCu_4 in the (B,T) - plane


  The puzzling properties of the first order phase transition in YbInCu$_4$ and
its alloys in the wide range of magnetic fields and temperatures are perfectly
described in terms of a simple entropy transition for free Yb ions. In
particular, it turns out that the transition line in the $(B,T)$-plane is very
close to the elliptic shape, as it has been observed experimentally. Similar
calculations are done, and the experiments are proposed for the
$(\gamma{-}\alpha)$ phase transition in Ce in Megagauss fields. We speculate,
that in case of YbInCu$_4$ the first order transition is a Mott transition
between a higher temperature phase in which localized moments are stabilized by
the entropy terms in the free energy, and a band-like non-magnetic ground state
of the $f$-electrons.

</DOC>
<DOC>
<DOCNO> 70615 </DOCNO>
Cosmic Microwave Background constraint on residual annihilations of


  Energy injected into the Cosmic Microwave Background at redshifts z<10^6 will
distort its spectrum permanently. In this paper we discuss the distortion
caused by annihilations of relic particles. We use the observational bounds on
deviations from a Planck spectrum to constrain a combination of annihilation
cross section, mass, and abundance. For particles with (s-wave) annihilation
cross section, <\sigma|v|>=\sigma_0, the bound is
f[(\sigma_0/6e-27cm^3/s)(\Omega_{X\bar{X}}h^2)^2]/(m_X/MeV)<0.2, where m_X is
the particle mass, \Omega_{X\bar{X}} is the fraction of the critical density
the particle and its antiparticle contribute if they survive to the present
time, h=H_0/(100km/s/Mpc), H_0 is the Hubble constant, and f is the fraction of
the annihilation energy that interacts electromagnetically. We also compute the
less stringent limits for p-wave annihilation. We update other bounds on
residual annihilations and compare them to our CMB bound.

</DOC>
<DOC>
<DOCNO> 117892 </DOCNO>
Multi-colour PL-relations of Cepheids in the Hipparcos catalogue and the


  We analyse a sample of 236 Cepheids from the Hipparcos catalog, using the
method of ``reduced parallaxes'' in V, I, K and the reddening-free
``Wesenheit-index''. We compare our sample to those considered by Feast &
Catchpole (1997) and Lanoix et al. (1999).
  We stress the importance of two systematic effects which influence the
distance to the LMC: the slopes of the Galactic PL-relations and metallicity
corrections. In order to assess the influence of these various effects, we
present 27 distance moduli (DM) to the LMC, based on three different colours
(V,I,K), three different slopes, and three different metallicity corrections.
  The DM to the LMC based on the parallax data can be summarised as follows.
Based on the PL-relation in V and I, and the Wesenheit-index, the DM is 18.60
\pm 0.11 (\pm 0.08 slope)(^{+0.08}_{-0.15} metallicity), which is our current
best estimate.
  Based on the PL-relation in K the DM is 18.52 \pm 0.18$ (\pm 0.03 slope) (\pm
0.06 metallicity)(^{+0.10}_{-0} sampling bias}).
  The random error is mostly due to the given accuracy of the Hipparcos
parallaxes and the number of Cepheids in the respective samples. The terms
between parentheses indicate the possible systematic uncertainties due to the
slope of the Galactic PL-relations, the metallicity corrections, and in the
K-band, due to the limited number of stars. Recent work by Sandage et al.
(1999) indicates that the effect of metallicity towards shorter distances may
be smaller in V and I than indicated here.

</DOC>
<DOC>
<DOCNO> 122226 </DOCNO>
Weak lensing mass reconstruction of MS1008.1-1224


  We present an in-depth weak lensing analysis of the cluster MS1008 based on
deep multicolor imaging obtained during the Science Verification of FORS1 at
the VLT. The image quality (half arcsec seeing) and depth of the VLT images
allow the shear signal to be mapped with high signal-to-noise and to be traced
out to 1.2 h_50^-1 Mpc, near the edge of the 6'.8x6'.8 field of view. Using
BVRI color information, as well as 81 redshifts in the field from the CNOC
survey, background galaxies can be effectively separated from cluster and
foreground objects. PSF distorsions are found to be moderate across the FORS
images and thus easily removed. Due to the small statistical errors in the mass
reconstruction, this dataset provides a testing ground where several systematic
effects (e.g. mass-sheet degeneracy, redshift distribution of the background
sources, cluster galaxy contamination) can be quantified. Several methods are
used to remove the mass-sheet degeneracy which is found to dominate the
systematic error budget. We measure a lower limit to the mass of 2.6 10^14
h_50^-1 M_sun within 1 h_50^-1 Mpc and a ``total'' mass of 5.3 10^14 h_50^-1
M_sun by fitting a softened isothermal sphere. The availability of the CNOC
redshift data and X-ray observations on this cluster allow a comparison of
different determinations of the mass radial profile. We find the lensing and
X-ray measurements in excellent agreement, while the mass derived from the
virial analysis is marginally (1-2 sigma) in agreement at radii where both
methods are reliable.

</DOC>
<DOC>
<DOCNO> 99772 </DOCNO>
Asymptotic growth of the number of classes of real plane algebraic


  The nonsingular real plane algebraic curves of given degree $d$ are
considered either up to isotopy or up to deformation. The asymptotic behavior
of the number $I_d$ of isotopy classes and the number $D_d$ of deformation
classes are studied. It is shown, in particular, that $log I_d\asypt d^2$.
Other related problems and their higher dimensional generalisations are
discussed.

</DOC>
<DOC>
<DOCNO> 123215 </DOCNO>
From the time-ordered data to the Maximum-Likelihood temperature maps of


  We review selected methods of the Cosmic Microwave Background data analysis
appropriate for the analysis of the largest currently available data sets. We
focus on techniques of the time-ordered data manipulation and map making
algorithms based on the maximum-likelihood approach. The presented methods have
been applied to the MAXIMA data analysis (Hanany et al 2000) and the
description of the algorithms is illustrated with the examples drawn from that
experience. The more extensive presentation of the here-mentioned issues will
be given in the forthcoming paper (Stompor et al 2001).

</DOC>
<DOC>
<DOCNO> 119371 </DOCNO>
The Behind The Plane Survey - source selection, identifications and


  We present details of the Behind The Plane survey of IRAS galaxies, which
extends the PSCz survey to cover the 93% of the sky with complete and reliable
IRAS data from the Point Source Catalog. At low latitudes, our catalogue is not
complete to 0.6Jy, but the incompleteness is physically understood and can be
corrected for. IRAS galaxies at low latitudes are heavily or completely
obscured optically, and are heavily outnumbered by Galactic sources with
similar IRAS properties. We have used radio, optical, mm, near and far-infrared
data to identify the galaxies, and the 2D catalogue is now complete. We have
used optical and HI spectroscopy to obtain redshifts for the galaxies; the
southern spectroscopy is completed and the north nearly so.

</DOC>
<DOC>
<DOCNO> 72288 </DOCNO>
Bose-Einstein effect from asymmetric sources in Monte Carlo generators


  We discuss the implementations of the Bose-Einstein effect from asymmetric
sources in Monte Carlo generators. A comparison of LEP data with results from
the PYTHIA/JETSET code with the standard procedure imitating the effect and
with the results from the weight method
 (with weights depending in various ways on components of momenta differences)
is presented. We show that in this last method one can reproduce the
experimental hierarchy of the source radii.

</DOC>
<DOC>
<DOCNO> 12263 </DOCNO>
Elastic Response of Rough Surfaces in Partial Contact


  We model numerically the partial normal contact of two elastic rough surfaces
with highly correlated asperities. Facing surfaces are unmated and described as
self-affine with a Hurst exponent H. The numerical algorithm is based on
Fourier acceleration and allows efficient simulation of very large systems. The
force, F, versus contact area, A, characteristics follows the law F = c
A^[(1+H)/2] in accordance with the suggestion of Roux et al. (Europhys. Lett.
23, 277 (1993)). However finite size corrections are very large even for
512X512 systems where the effective exponent is still 20% larger than its
asymptotic value.

</DOC>
<DOC>
<DOCNO> 99984 </DOCNO>
Dimension $n$ Representations of the Braid Group on $n$ Strings


  In 1996 E. Formanek classified all the irreducible complex representations of
$B_n$ of dimension at most $n-1,$ where $B_n$ is the Artin braid group on $n$
strings. In this paper we extend this classification to the representations of
dimension $n,$ for $n\geq 9$. We prove that all such representations are
equivalent to a tensor product of a one-dimensional representation and a
specialization of a certain one-parameter family of $n-$dimensional
representations, that was first discovered in 1996 by Tong, Yang, and Ma. We
use our classification of irreducible complex representations of corank two, in
the preprint math.GR/0003047.

</DOC>
<DOC>
<DOCNO> 116619 </DOCNO>
Characteristics of highly excited diatomic rovibrational spectra and


  We show that the highly excited rovibrational spectra of a diatomic molecule
and the closely related slow atomic collision processes contain more
systematics and require less parameters to characterize than the Rydberg
spectrum of an atom. In the case of a single channel, for example, we show that
a single short-range parameter gives a complete description of slow collisions
for practically all angular momenta, and covers an energy range of hundreds of
millikelvins. The same parameter also describes the highly excited
rovibrational spectra in the threshold region, including states of different
angular momenta. Sample applications and predictions of the theory are
discussed, including comparisons with experiment.

</DOC>
<DOC>
<DOCNO> 68630 </DOCNO>
Neutralino Production with Polarized Beams in Extended Supersymmetric


  We discuss associated neutralino production e^+ e^- --> \tilde{\chi}^0_1
\tilde{\chi}^0_2 with both beams polarized in the MSSM, NMSSM and an E_6 model.
It is shown that neutralinos with a large singlino component can be produced at
a high luminosity linear collider in a broad parameter range. Polarization
effects in the extended models are compared over the whole parameter space
where the lightest neutralino is mainly a singlino. We explain the complete
different behavior of these models in some parameter regions, which may help to
identify the respective supersymmetric model.

</DOC>
<DOC>
<DOCNO> 70808 </DOCNO>
What if the Higgs Boson Weighs 115 GeV?


  If the Higgs boson indeed weighs about 114 to 115 GeV, there must be new
physics beyond the Standard Model at some scale \la 10^6 GeV. The most
plausible new physics is supersymmetry, which predicts a Higgs boson weighing
\la 130 GeV. In the CMSSM with R and CP conservation, the existence, production
and detection of a 114 or 115 GeV Higgs boson is possible if \tan\beta \ga 3.
However, for the radiatively-corrected Higgs mass to be this large, sparticles
should be relatively heavy: m_{1/2} \ga 250 GeV, probably not detectable at the
Tevatron collider and perhaps not at a low-energy e^+ e^- linear collider. In
much of the remaining CMSSM parameter space, neutralino-stau coannihilation is
important for calculating the relic neutralino density, and we explore
implications for the elastic neutralino-nucleon scattering cross section.

</DOC>
<DOC>
<DOCNO> 12476 </DOCNO>
Interplay of the Scaling Limit and the Renormalization Group:


  Symmetry restoration is usually understood as a renormalization group induced
phenomenon. In this context, the issue of whether one-loop RG equations can be
trusted in predicting symmetry restoration has recently been the subject of
much debate. Here we advocate a more pragmatic point of view and expand the
definition of symmetry restoration to encompass all situations where the
physical properties have only a weak dependence upon an anisotropy in the bare
couplings. Moreover we concentrate on universal properties, and so take a
scaling limit where the physics is well described by a field theory. In this
context, we find a large variety of models that exhibit, for all practical
purposes, symmetry restoration: even if symmetry is not restored in a strict
sense, physical properties are surprisingly insensitive to the remaining
anisotropy.
  Although we have adopted an expanded notion of symmetry restoration, we
nonetheless emphasize that the scaling limit also has implications for symmetry
restoration as a renormalization group induced phenomenon. In all the models we
considered, the scaling limit turns out to only permit bare couplings which are
nearly isotropic and small. Then the one-loop beta-function should contain all
the physics and higher loop orders can be neglected. We suggest that this
feature generalizes to more complex models. We exhibit a large class of
theories with current-current perturbations (of which the SO(8) model of
interest in two-leg Hubbard ladders/armchair carbon nanotubes is one) where the
one-loop beta-functions indicates symmetry restoration and so argue that these
results can be trusted within the scaling limit.

</DOC>
<DOC>
<DOCNO> 117229 </DOCNO>
Fluid Particle Accelerations in Fully Developed Turbulence


  The motion of fluid particles as they are pushed along erratic trajectories
by fluctuating pressure gradients is fundamental to transport and mixing in
turbulence. It is essential in cloud formation and atmospheric transport,
processes in stirred chemical reactors and combustion systems, and in the
industrial production of nanoparticles. The perspective of particle
trajectories has been used successfully to describe mixing and transport in
turbulence, but issues of fundamental importance remain unresolved. One such
issue is the Heisenberg-Yaglom prediction of fluid particle accelerations,
based on the 1941 scaling theory of Kolmogorov (K41). Here we report
acceleration measurements using a detector adapted from high-energy physics to
track particles in a laboratory water flow at Reynolds numbers up to 63,000. We
find that universal K41 scaling of the acceleration variance is attained at
high Reynolds numbers. Our data show strong intermittency---particles are
observed with accelerations of up to 1,500 times the acceleration of gravity
(40 times the root mean square value). Finally, we find that accelerations
manifest the anisotropy of the large scale flow at all Reynolds numbers
studied.

</DOC>
<DOC>
<DOCNO> 9780 </DOCNO>
Complex orbital state in manganites


  The $e_g$-orbital states with complex coefficients of the linear combination
of $x^2-y^2$ and $3z^2-r^2$ are studied for the ferromagnetic state in doped
manganites. Especially the focus is put on the competition among uniform
complex, staggered complex, and real orbital states. As the hole-doping $x$
increases, the real, the canted complex, and the staggered complex orbital
states appears successively. Uniform complex state analoguous to Nagaoka
ferromagnet does not appear. These complex states can be expressed as a
resonating state among the planer orbitals as the orbital liquid, accompanied
by no Jahn-Teller distortion.

</DOC>
<DOC>
<DOCNO> 39932 </DOCNO>
Measurement of elastic electroproduction of phi mesons at HERA


  The elastic electroproduction of phi mesons is studied at HERA with the H1
detector for photon virtualities 1 < Q^2 < 15 GeV^2 and hadronic centre of mass
energies 40 < W < 130 GeV. The Q^2 and t dependences of the cross section are
extracted (t being the square of the four-momentum transfer to the target
proton). When plotted as function of (Q^2 + M_V^2) and scaled by the
appropriate SU(5) quark charge factor, the phi meson cross section agrees
within errors with the cross sections of the vector mesons V = rho, omega and
J/psi. A detailed analysis is performed of the phi meson polarisation state and
the ratio of the production cross sections for longitudinally and transversely
polarised phi mesons is determined. A small but significant violation of
s-channel helicity conservation (SCHC) is observed.

</DOC>
<DOC>
<DOCNO> 150470 </DOCNO>
Bundles of chiral blocks and boundary conditions in CFT


  Various aspects of spaces of chiral blocks are discussed. In particular,
conjectures about the dimensions of irreducible sub-bundles are reviewed and
their relation to symmetry breaking conformal boundary conditions is outlined.

</DOC>
<DOC>
<DOCNO> 70515 </DOCNO>
Four neutrino oscillation analysis of atmospheric neutrino data and


  Analyis of the Superkamiokande atmospheric neutrino data is presented in the
framework of four neutrinos without imposing constraints of Big Bang
Nucleosynthesis. Implications to long baseline experiments are briefly
discussed.

</DOC>
<DOC>
<DOCNO> 85041 </DOCNO>
The asymptotic regimes of tilted Bianchi II cosmologies


  In this paper we give, for the first time, a complete description of the
dynamics of tilted spatially homogeneous cosmologies of Bianchi type II. The
source is assumed to be a perfect fluid with equation of state $p = (\gamma -1)
\mu$, where $\gamma$ is a constant. We show that unless the perfect fluid is
stiff, the tilt destabilizes the Kasner solutions, leading to a Mixmaster-like
initial singularity, with the tilt being dynamically significant. At late times
the tilt becomes dynamically negligible unless the equation of state parameter
satisfies $\gamma > {10/7}$. We also find that the tilt does not destabilize
the flat FL model, with the result that the presence of tilt increases the
likelihood of intermediate isotropization.

</DOC>
<DOC>
<DOCNO> 151327 </DOCNO>
Brane-World Black Holes in Randall-Sundrum Models


  We study brane-world black holes from Randall-Sundrum(RS) models in
($D+1$)-dimensional anti-de Sitter spacetimes. The solutions are directly
obtained by using a slightly modified RS metric ansatz in $D+1$ dimensions. The
metric of the brane world can be described by the Schwarzschild solution
promoted to the black cigar solution in $D+1$ dimensions, which is compatible
with the recently suggested black cigar solution for D=4. Furthermore, we show
that the Ricci flat condition for the brane can be easily derived from the
effective gravity defined on the brane by using the RS dimensional reduction.
Especially, it is shown that in two dimensions the effective gravity on the
brane is described by the Polyakov action.

</DOC>
<DOC>
<DOCNO> 11918 </DOCNO>
Ferromagnetism in the Periodic Anderson Model - a Modified Alloy Analogy


  We introduce a new aproximation scheme for the periodic Anderson model (PAM).
The modified alloy approximation represents an optimum alloy approximation for
the strong coupling limit, which can be solved within the CPA-formalism.
Zero-temperature and finite-temperature phase diagrams are presented for the
PAM in the intermediate-valence regime. The diversity of magnetic properties
accessible by variation of the system parameters can be studied by means of
quasiparticle densities of states: The conduction band couples either ferro- or
antiferromagneticaly to the f-levels. A finite hybridization is a necessary
precondition for ferromagnetism. However, too strong hybridization generally
suppresses ferromagnetism, but can for certain system parameters also lead to a
semi-metallic state with unusual magnetic properties. By comparing with the
spectral density approximation, the influence of quasiparticle damping can be
examined.

</DOC>
<DOC>
<DOCNO> 169907 </DOCNO>
Sampling the canonical phase from phase-space functions


  We discuss the possibility of sampling exponential moments of the canonical
phase from the s-parametrized phase space functions. We show that the sampling
kernels exist and are well-behaved for any s>-1, whereas for s=-1 the kernels
diverge in the origin. In spite of that we show that the phase space moments
can be sampled with any predefined accuracy from the Q-function measured in the
double-homodyne scheme with perfect detectors. We discuss the effect of
imperfect detection and address sampling schemes using other measurable
phase-space functions. Finally, we discuss the problem of sampling the
canonical phase distribution itself.

</DOC>
<DOC>
<DOCNO> 117942 </DOCNO>
Quantum corrections to the ground state energy of inhomogeneous neutron


  We estimate the quantum corrections to the ground state energy in neutron
matter (which could be termed as well either shell correction energy or Casimir
energy) at subnuclear densities, where various types of inhomogeneities
(bubbles, rods, plates) are energetically favorable. We show that the magnitude
of these energy corrections are comparable to the energy differences between
various types of inhomogeneous phases. We discuss the dependence of these
corrections on a number of physical parameters (density, filling factor,
temperature, lattice distortions).

</DOC>
<DOC>
<DOCNO> 12923 </DOCNO>
Quantum discreteness and fundamental 1/f noise in tunnel junctions,


  It is shown, with citing tunnel junction as an example, that mutual interplay
of electron quantum transfers in a conducting system can be the fast mechanism
for generation fundamental low-frequency flicker conductance fluctuations (1/f
noise) without composing Lorentzians. This effect is lost in a theory which
neglects the actual discreteness of electron energy levels. The analytical
estimates of fluctuations of tunnel conductance are obtained, and the strong
1/f-noise sensibility to the discreteness as observed in nano-composites is
explained both qualitatively and quantitatively.

</DOC>
<DOC>
<DOCNO> 83196 </DOCNO>
Applying MDL to Learning Best Model Granularity


  The Minimum Description Length (MDL) principle is solidly based on a provably
ideal method of inference using Kolmogorov complexity. We test how the theory
behaves in practice on a general problem in model selection: that of learning
the best model granularity. The performance of a model depends critically on
the granularity, for example the choice of precision of the parameters. Too
high precision generally involves modeling of accidental noise and too low
precision may lead to confusion of models that should be distinguished. This
precision is often determined ad hoc. In MDL the best model is the one that
most compresses a two-part code of the data set: this embodies ``Occam's
Razor.'' In two quite different experimental settings the theoretical value
determined using MDL coincides with the best value found experimentally. In the
first experiment the task is to recognize isolated handwritten characters in
one subject's handwriting, irrespective of size and orientation. Based on a new
modification of elastic matching, using multiple prototypes per character, the
optimal prediction rate is predicted for the learned parameter (length of
sampling interval) considered most likely by MDL, which is shown to coincide
with the best value found experimentally. In the second experiment the task is
to model a robot arm with two degrees of freedom using a three layer
feed-forward neural network where we need to determine the number of nodes in
the hidden layer giving best modeling performance. The optimal model (the one
that extrapolizes best on unseen examples) is predicted for the number of nodes
in the hidden layer considered most likely by MDL, which again is found to
coincide with the best value found experimentally.

</DOC>
<DOC>
<DOCNO> 119486 </DOCNO>
Imaging of Ultraluminous Infrared Galaxies in the Near-UV


  We present the first ground-based U' (3410 angstroms) images of Ultraluminous
Infrared Galaxies (ULIGs). Strong U' emission (median total M_U' = -20.8) is
seen in all systems and in some cases the extended tidal features (both the
smooth stellar distribution and compact star-forming features) contribute up to
60-80% of the total flux. The star-forming regions in both samples are found to
have ages based on spectral synthesis models in the range 10-100 Myrs, and most
differences in color between them can be attributed to the effects of dust
reddening. Additionally, it is found that star-formation in compact knots in
the tidal tails is most prominent in those ULIGs which have double nuclei,
suggesting that the star-formation rate in the tails peaks prior to the actual
coalescence of the galaxy nuclei and diminishes quickly thereafter. Similar to
results at other wavelengths, the observed star formation at U' can only
account for a small fraction of the known bolometric luminosity of the ULIGs.
Azimuthally averaged radial light profiles at U' are characterized by a sersic
law with index n=2, which is intermediate between an exponential disk and an
r^(-1/4) law and closely resembles the latter at large radii. The implications
of this near-ultraviolet imaging for optical/near-infrared observations of high
redshift counterparts of ULIGs are discussed.

</DOC>
<DOC>
<DOCNO> 71761 </DOCNO>
|V_{ub}| From Semileptonic Decay and b -> s gamma


  Current errors on |V_{ub}| are dominated by model dependence. For inclusive
decays, the model dependence comes from the Fermi motion of the b quark. By
combining the endpoint photon and lepton spectra from the inclusive decays B ->
X_s gamma and B -> X_u l nu, it is possible to remove this model dependence. We
show how to combine these rates including the resummation of the endpoint logs
at next to leading order. The theoretical errors on |V_{ub}| on the order of
10% are possible. We also give a brief discussion on comparing different
extractions.

</DOC>
<DOC>
<DOCNO> 84188 </DOCNO>
Gravitational Waves from Low-Mass X-ray Binaries: a Status Report


  We summarize the observations of the spin periods of rapidly accreting
neutron stars. If gravitational radiation is responsible for balancing the
accretion torque at the observed spin frequencies of ~300 Hz, then the
brightest of these systems make excellent gravitational wave sources for
LIGO-II and beyond. We review the recent theoretical progress on two mechanisms
for gravitational wave emission: mass quadrupole radiation from deformed
neutron star crusts and current quadrupole radiation from r-mode pulsations in
neutron star cores.

</DOC>
<DOC>
<DOCNO> 13929 </DOCNO>
Conductance and density of states as the Kramers-Kronig dispersion


  By applying the Kramers-Kronig dispersion relation to the transmission
amplitude a direct connection of the conductance with the density of states is
given in quantum scattering systems connected to two one-channel leads.
   Using this method we show that in the Fano resonance the peak position of
the density of states is generally different from the position of the
corresponding conductance peak, whereas in the Breit-Wigner resonance those
peak positions coincide.
   The lineshapes of the density of states are well described by a Lorentz type
in the both resonances.
   These results are verified by another approach using a specific form of the
scattering matrix to describe scattering resonances.

</DOC>
<DOC>
<DOCNO> 152174 </DOCNO>
Conformal Higher Spin Currents in Any Dimension and AdS/CFT


  The full list of conserved conformal higher spin currents built from massless
scalar and spinor fields is presented. It is shown that, analogously to the
relationship between usual conformal and AdS symmetries, the set of the
conformal higher spin symmetry parameters associated with the conformal
conserved currents in d dimensions is in the one-to-one correspondence with the
result of the dimensional reduction of the usual (i.e., non-conformal) higher
spin symmetry parameters in d+1 dimensions.

</DOC>
<DOC>
<DOCNO> 116609 </DOCNO>
Sub-Doppler resolution with double coherently driving fields


  We propose a four-level model where sub-Doppler resolution as well as
enhanced absorption of a weak probe field are realized by using two coherently
driving fields. We show that spectral resolution can be improved by modifying
the coherent fields intensity and frequencies.

</DOC>
<DOC>
<DOCNO> 179031 </DOCNO>
Effective Field Theory in Nuclear Physics


  The Electromagnetic and Hadronic Physics sub-community of nuclear physics
held a town hall meeting at Jefferson Lab during November 30 to December 4 of
2000. This is is our combined contribution to the white paper that will result
from this meeting.

</DOC>
<DOC>
<DOCNO> 101373 </DOCNO>
Representations of the Schrodinger algebra and Appell systems


  We investigate the structure of the Schrodinger algebra and its
representations in a Fock space realized in terms of canonical Appell systems.
Generalized coherent states are used in the construction of a Hilbert space of
functions on which certain commuting elements act as self-adjoint operators.
This yields a probabilistic interpretation of these operators as random
variables. An interesting feature is how the structure of the Lie algebra is
reflected in the probability density function. A Leibniz function and
orthogonal basis for the Hilbert space is found. Then Appell systems connected
with certain evolution equations, analogs of the classical heat equation, on
this algebra are computed.

</DOC>
<DOC>
<DOCNO> 13727 </DOCNO>
Phonons and related properties of extended systems from


  This article reviews the current status of lattice-dynamical calculations in
crystals, using density-functional perturbation theory, with emphasis on the
plane-wave pseudo-potential method. Several specialized topics are treated,
including the implementation for metals, the calculation of the response to
macroscopic electric fields and their relevance to long wave-length vibrations
in polar materials, the response to strain deformations, and higher-order
responses. The success of this methodology is demonstrated with a number of
applications existing in the literature.

</DOC>
<DOC>
<DOCNO> 11778 </DOCNO>
Anomalous relaxation and self-organization in non-equilibrium processes


  We study thermal relaxation in ordered arrays of coupled nonlinear elements
with external driving. We find, that our model exhibits dynamic
self-organization manifested in a universal stretched-exponential form of
relaxation. We identify two types of self-organization, cooperative and
anti-cooperative, which lead to fast and slow relaxation, respectively. We give
a qualitative explanation for the behavior of the stretched exponent in
different parameter ranges. We emphasize that this is a system exhibiting
stretched-exponential relaxation without explicit disorder or frustration.

</DOC>
<DOC>
<DOCNO> 71221 </DOCNO>
Electromagnetic Contributions to Lepton g-2 in a Thick Brane-World


  We consider Standard Model fields living inside a thick four dimensional flat
brane embedded in a (possibly warped) five dimensional space-time and estimate
the electromagnetic corrections to the anomalous magnetic moment (g-2) of the
electron and muon by including virtual massive fermion and gauge boson states.
Constraints on the mass of the ``excited'' states (or thickness of the
brane-world) are obtained.

</DOC>
<DOC>
<DOCNO> 150863 </DOCNO>
FFZ realization of the deformed super Virasoro algebra -


  The q-deformed super Virasoro algebra proposed by Chaichian and Presnajder is
examined. Presented is the realizations by the FFZ algebra (the magnetic
translation algebra) defined on a two-dimensional lattice with a supersymmetric
Hamiltonian.

</DOC>
<DOC>
<DOCNO> 116776 </DOCNO>
Complete Entanglement-Based Communication With Security


  If, due to some catastrophe, our classical communication system is destroyed
but quantum entangled state survived, in that entanglement age, it is widely
believed, the whole world would be communication less. It is discussed that
complete entanglement based communication even with security is possible in
that scenario. In this context, the notion of cheating-free Bell's inequality
test is introduced.

</DOC>
<DOC>
<DOCNO> 120590 </DOCNO>
Deep Optical Imaging of A Compact Group of Galaxies, Seyfert's Sextet


  In order to investigate the dynamical status of Seyfert's Sextet (SS), we
have obtained a deep optical ($VR+I$) image of this group. Our image shows that
a faint envelope, down to a surface brightness $\mu_{\rm optical}$(AB) $\simeq
27$ mag arcsec$^{-2}$, surrounds the member galaxies. This envelope is
irregular in shape. It is likely that this shape is attributed either to
recent-past or to on-going galaxy interactions in SS. If the member galaxies
have experienced a number of mutual interactions over a long timescale, the
shape of the envelope should be rounder. Therefore, the irregular-shaped
morphology suggests that SS is in an early phase of dynamical interaction among
the member galaxies. It is interesting to note that the soft X-ray image
obtained with ROSAT (Pildis et al. 1995) is significantly similar in
morphology. We discuss the possible future evolution of SS briefly.

</DOC>
<DOC>
<DOCNO> 118292 </DOCNO>
Properties of Gamma-Ray Burst Time Profiles Using Pulse Decomposition


  The time profiles of many gamma-ray bursts consist of distinct pulses, which
offers the possibility of characterizing the temporal structure of these bursts
using a relatively small set of pulse shape parameters. This pulse
decomposition analysis has previously been performed on a small sample of
bright long bursts using binned data from BATSE, which comes in several data
types, and on a sample of short bursts using the BATSE Time-Tagged Event (TTE)
data type. We have developed an interactive pulse-fitting program using the
phenomenological pulse model of Norris, et al. and a maximum-likelihood fitting
routine. We have used this program to analyze the Time-to-Spill (TTS) data for
all bursts observed by BATSE up through trigger number 2000, in all energy
channels for which TTS data is available. We present statistical information on
the attributes of pulses comprising these bursts, including relations between
pulse characteristics in different energy channels and the evolution of pulse
characteristics through the course of a burst. We carry out simulations to
determine the biases that our procedures may introduce. We find that pulses
tend to have shorter rise times than decay times, and tend to be narrower and
peak earlier at higher energies. We also find that pulse brightness, pulse
width, and pulse hardness ratios do not evolve monotonically within bursts, but
that the ratios of pulse rise times to decay times tend to decrease with time
within bursts.

</DOC>
<DOC>
<DOCNO> 99613 </DOCNO>
Extensions of diffeomorphism and current algebras


  Dzhumadil'daev has classified all tensor module extensions of $diff(N)$, the
diffeomorphism algebra in $N$ dimensions, and its subalgebras of divergence
free, Hamiltonian, and contact vector fields. I review his results using
explicit tensor notation. All of his generic cocycles are limits of trivial
cocycles, and many arise from the Mickelsson-Faddeev algebra for $gl(N)$. Then
his results are extended to some non-tensor modules, including the
higher-dimensional Virasoro algebras found by Eswara Rao/Moody and myself.
Extensions of current algebras with $d$-dimensional representations are
obtained by restriction from $diff(N+d)$. This gives a connection between
higher-dimensional Virasoro and Kac-Moody cocycles, and between
Mickelsson-Faddeev cocycles for diffeomorphism and current algebras.

</DOC>
<DOC>
<DOCNO> 70010 </DOCNO>
Universal Unitarity Triangle and Physics Beyond the Standard Model


  We make the simple observation that there exists a universal unitarity
triangle for all models, like the SM, the Two Higgs Doublet Models I and II and
the MSSM with minimal flavour violation, that do not have any new operators
beyond those present in the SM and in which all flavour changing transitions
are governed by the CKM matrix with no new phases beyond the CKM phase. This
universal triangle can be determined in the near future from the ratio (Delta
M)_d/(Delta M)_s and sin(2 beta) measured first through the CP asymmetry in
B_d^0 to psi K_S and later in K to pi nu nubar decays. Also suitable ratios of
the branching ratios for B to X_{d,s} nu nubar and B_{d,s} to mu^+ mu^- and the
angle gamma measured by means of CP asymmetries in B decays can be used for
this determination. Comparison of this universal triangle with the
non-universal triangles extracted in each model using epsilon, (Delta M)_d and
various branching ratios for rare decays will allow to find out in a
transparent manner which of these models, if any, is singled out by experiment.
A virtue of the universal triangle is that it allows to separate the
determination of the CKM parameters from the determination of new parameters
present in the extensions of the SM considered here.

</DOC>
<DOC>
<DOCNO> 116777 </DOCNO>
About nondegenerative four photon mixing gain spectroscopy of the SF_6


  Infrared-infrared double resonance measurements of the $\nu_3$ absorption
band of $SF_6$ using a $CO_2$ TEA laser radiation have been carried out. The
results obtained in the present and in some earlier works are discussed taking
into account existence of a wide component of lines, nondegenerative four
photon mixing (NFPM) and time invariance violation in the photon-molecule
interactions. It is proposed to use the NFPM effect in investigations of the
shape of the optical transition in polyatomic molecules and especially for
evaluation of the homogeneous width of the wide component of lines. The need
and problems of experimental study of existing effects of the T-invariance
violation in optics are discussed.

</DOC>
<DOC>
<DOCNO> 39723 </DOCNO>
Status of the Muon (g-2) Experiment


  The status of the muon (g-2) experiment, E821 at the Brookhaven AGS, is
given. A new result with a precision of 5 parts per million has been obtained
with direct muon injection into the ring and is presented. The theoretical
motivation for the experiment, and a discussion of the sensitivity to
non-standard model physics is also discussed.

</DOC>
<DOC>
<DOCNO> 120908 </DOCNO>
Comparing Ultraviolet and H alpha Star Formation Rates


  We have used a sample of 43 star-forming galaxies imaged in the
far-ultraviolet (FUV) by the UIT supplemented with 33 galaxies observed by
FAUST, to explore the consistency of UV and H alpha derived star formation
rates (SFRs). We find, even before correction for dust, that UV and H alpha
SFRs are quantitatively consistent for low-luminosity galaxies, and that higher
luminosity galaxies have H alpha SFRs a factor of 1.5 higher than their UV
SFRs: this reflects the influence of dust. Our results are consistent with a
scenario where the UV dust extinction is a factor of less than 2 larger than
the H alpha dust extinction in a given galaxy, and that there is over a 4
magnitude range of H alpha dust extinctions which correlate loosely with galaxy
luminosity such that low luminosity galaxies tend to have lower extinctions
than their higher luminosity counterparts.

</DOC>
<DOC>
<DOCNO> 119509 </DOCNO>
FOS Observations of Four NLS1s


  Ultraviolet through optical spectroscopy of four NLS1s shows strong
absorption features in the high-ionization UV resonance lines such as C IV, N
V, and Si IV. Mg II is not absorbed. The absorption could originate in the warm
absorber.

</DOC>
<DOC>
<DOCNO> 119499 </DOCNO>
Are Narrow-Line Seyfert 1s Really Strange?


  Narrow-Line Seyfert 1s (NLS1s) are generally considered to be strange Active
Galactic Nuclei (AGNs). Surprisingly, this makes them very useful for
constraining models. I discuss what happens when one attempts to qualitatively
fit the NLS1 phenomenon using the stellar wind model for AGN line emission
(e.g., Kazanas 1989). The simplest way of narrowing profile bases of this model
to the widths observed in NLS1s is probably to lower the mass of the
supermassive black hole. In a flux-limited and redshift-limited data set, this
is indeed similar to increasing L/L_Edd. Because the broad line region (BLR) of
the stellar line emission model scales with the tidal radius of the stars, this
model predicts maximal BLR velocities of FWZI proportional (L/L_Edd)^(-1/3).
This implies that the black holes of NLS1s are approximately 3^3=27 times less
massive than those in other Seyfert 1s if the stellar line emission model is
correct. Another consequence of increasing L/L_Edd in this model is that it
results in an increase in the wind edge densities. NLS1 spectra appear to
support this result as well. Even the collateral features of NLS1s, such as the
line asymmetries and continuum properties, appear to be easily explained within
the context of this model. For better or worse, if the stellar wind line
emission is correct, NLS1s are not much stranger than other AGNs.

</DOC>
<DOC>
<DOCNO> 8099 </DOCNO>
Luttinger Liquid Physics in the Superconductor Vortex Core


  We study several aspects of the structure of vortices in conventional s-wave
Type $II$ superconductors. It is well-known that there are low energy
quasiparticles bound to the core of a vortex. We show that under certain
conditions, these quasiparticles form a degenerate Fermi gas with a finite
density of states at the Fermi energy. In three dimensional superconductors,
the result is a one dimensional Fermi gas of quasiparticles bound to the core
of a vortex line. As is usual in one dimensional systems, interactions between
the quasiparticles lead to Luttinger liquid behaviour. This may be probed
through STM tunneling into the vortex core. We further suggest that a novel
Peierls-type instability in the shape of the vortex line may develop due to
interactions between the quasiparticle gas and fluctuations in the vortex line
shape.

</DOC>
<DOC>
<DOCNO> 67856 </DOCNO>
On a possibility to determine the S-factor of the hep process in


  The problem of the magnitude of the S--factor of the hep process $p +
{^3\mathrm{He}} \to {^4\mathrm{He}} + e^+ + \nu_e$ is one of the most important
unsolved problems in nuclear astrophysics. The magnitude of $S(hep)$ has also
an important impact on the interpretation of the Super-Kamiokande solar
neutrino results in terms of neutrino oscillations. We point out the possiblity
to determine the major hadronic contribution to $S(hep)$ from the measurement
of the total cross section of the process $n + {^3\mathrm{H}} \to
{^4\mathrm{He}} + e^- + \bar{\nu}_e$ in experiments with high intensity beams
of thermal or cold neutrons.

</DOC>
<DOC>
<DOCNO> 69814 </DOCNO>
Radiative $\phi$$-$meson decays and $\eta$-$\eta^\prime$ mixing: a QCD


  The radiative transitions $\phi \to \eta \gamma$ and $\phi \to \eta^\prime
\gamma$ are analysed using QCD sum-rules. The results we obtain for ${\cal
B}(\phi \to \eta \gamma)=(1.15 \pm 0.2) 10^{-2}$ and ${\cal B}(\phi \to
\eta^\prime \gamma)=(1.18 \pm 0.4) 10^{-4}$ are in very good agreement with
existing experimental data. The related issue of $\eta-\eta^\prime$ mixing is
discussed and we give predictions for the $\eta$ and $\eta^\prime$ decay
constants in the framework of a mixing scheme in the quark-flavour basis.

</DOC>
<DOC>
<DOCNO> 7943 </DOCNO>
The interacting system of electrons, positrons and photons in high


  The connected system of Boltzman equations for the interacting system of
electrons, positrons and photons in high external electric E and arbitrary
magnetic H fields is solved. The consideration is made under the conditions of
arbitrary heating and the mutual drag of carriers and photons.
  The non-stationary and non-uniform distribution function (DF) of photons for
the all considered cases is obtained. It is shown that the DF of photons have
the stationary limit for the drift velocities $(\overset{\to
}\to{u}\overset{\to}\to{q}/\hbar \omega_q) <1$ and becomes exponentially grown
by the time for the drift velocities
$(\overset{\to}\to{u}\overset{\to}\to{q}/\hbar \omega_q) \geq 1$. It is shown
that the mutual drag of carriers and photons leads to the formation of
''quasi-particles''\_ the ''electron dressed by photons'' and ''positron
dressed by photons'', i.e. the mutual drag plays the role of the dressing
mechanism of carriers and leads to the renormalization of the mass and
frequency of photons.
  As a result of analyses of the phenomena of connected by the mutual drag
system of carriers and photons we receive some fundamental results: a) the
finiteness of the mass of photon (i.e. the rest mass of photons do not equal to
zero); b) reality of takhyons as a quasi-particles with the real mass in
amplifying system (or regime); c) identity of the mechanism of relativity and
the Doppler effect which coincides with the renormalization of frequency or
mass as a result of the mutual drag of carriers and photons at external field
(force). These conclusions were received as a result of the fact that the
relativistic factor enters to the expressions of the DF of photons and other
physical expressions in the first order in the form $[ 1-(u^2/c^2) ] ^{-1}$,
instead the $[ 1-(u^2/c^2) ] ^{-1/2}$ in Einstein theory. It is shown that the
relativistic effect of deceleration of time really taking place for the
relaxation time of carriers or for the life time of carriers, or for the period
of electromagnetic oscillations. The latest is a direct result of the Doppler
effect. Also it is shown that the velocity of light is an averaged velocity of
photons at the ground state, as well as a velocity of sound for the phonons.

</DOC>
<DOC>
<DOCNO> 118413 </DOCNO>
Low Frequency Radio Emission of Pulsar PSR J1907+0919 Associated with


  The soft gamma repeater SGR 1900+14 was observed in Pushchino observatory
since 1988 December using BSA radio telescope operating at 111 MHz. We have
detected the pulsed radio emission (Shitov 1999) with the same 5.16 s period
that was reported earlier for this object. The timing analysis has shown that
this new radio pulsar PSR J1907+0919 associated with SGR 1900+14 has a
superstrong magnetic field, which is 8.1 * 10^14 G, thereby confirming that it
is a "magnetar". The dispersion measure of PSR J1907+0919 is 281.4(9) pc *
cm^(-3) which gives an estimate of the pulsar's distance as about 5.8 kpc.

</DOC>
<DOC>
<DOCNO> 85593 </DOCNO>
Casimir energy and black hole pair creation in Schwarzschild-de Sitter


  Following the subtraction procedure for manifolds with boundaries, we
calculate by variational methods, the Schwarzschild-de Sitter and the de Sitter
space energy difference. By computing the one loop approximation for TT tensors
we discover the existence of an unstable mode even for the non-degenerate case.
This result seems to be in agreement with the sub-maximal black hole pair
creation of Bousso-Hawking. The instability can be eliminated by the boundary
reduction method. Implications on a foam-like space are discussed.

</DOC>
<DOC>
<DOCNO> 152062 </DOCNO>
Boundary bound states in integrable quantum field theories


  The purpose of this talk is to sketch some recent progress which has been
made in calculating non-perturbatively the reflection factors for the
sinh-Gordon model restricted to a half-line by integrable boundary conditions.
The essential idea is to calculate the energy spectrum of boundary breathers in
two independent ways; firstly by using the boundary bootstrap and secondly by
quantizing the classical solutions corresponding to boundary breathers.
Comparing these two calculations provides a way to determine the dependence of
the reflection factors on the parameters introduced into the Lagrangian by the
boundary conditions. The basic idea is illustrated using a massive free scalar
field with a linear boundary condition confining it to a half-line.

</DOC>
<DOC>
<DOCNO> 120220 </DOCNO>
The Vela Pulsar and its Synchrotron Nebula


  (Abridged) We present high-resolution Chandra X-ray observations of PSR
B0833-45, the 89 ms pulsar associated with the Vela supernova remnant. We have
acquired two observations separated by one month to search for changes in the
pulsar and its environment following an extreme glitch in its rotation
frequency. We find a well-resolved nebula with a toroidal morphology remarkably
similar to that observed in the Crab Nebula, along with an axial Crab-like jet.
Between the two observations the flux from the pulsar is found to be steady to
within 0.75%; the 3 sigma limit on the fractional increase in the pulsar's
X-ray flux is < ~10^-5 of the inferred glitch energy. We use this limit to
constrain parameters of glitch models and neutron star structure. We do find a
significant increase in the flux of the nebula's outer arc; if associated with
the glitch, the inferred propagation velocity is > 0.7c, similar to that seen
in the brightening of the Crab Nebula wisps. We propose an explanation for the
X-ray structure of the Vela synchrotron nebula based on a model originally
developed for the Crab Nebula. In a departure from the Crab model, the
magnetization parameter "sigma" of the Vela pulsar wind is allowed to be of
order unity; this is consistent with the simplest MHD transport of magnetic
field from the pulsar to the nebula, where B < 4 X 10^-4 G. We review effects
that may enhance the probability of alignment between the spin axis and space
velocity of a pulsar, and speculate that short-period, slowly moving pulsars
are just the ones best-suited to producing synchrotron nebulae with such
aligned structures.

</DOC>
<DOC>
<DOCNO> 69573 </DOCNO>
Electromagnetism in nonleptonic weak interactions


  We construct a low-energy effective field theory that permits the complete
treatment of isospin-breaking effects in nonleptonic weak interactions to
next-to-leading order. To this end, we enlarge the chiral Lagrangian describing
strong and Delta S=1 weak interactions by including electromagnetic terms with
the photon as additional dynamical degree of freedom. The complete and minimal
list of local terms at next-to-leading order is given. We perform the one-loop
renormalization at the level of the generating functional and specialize to K
-> pi pi decays.

</DOC>
<DOC>
<DOCNO> 13437 </DOCNO>
Dephasing of Electrons by Two-Level Defects in Quantum Dots


  The electron dephasing time $\tau_{\phi}$ in a diffusive quantum dot is
calculated by considering the interaction between the electron and dynamical
defects, modelled as two-level system. Using the standard tunneling model of
glasses, we obtain a linear temperature dependence of $1/\tau_{\phi}$,
consistent with the experimental observation. However, we find that, in order
to obtain dephasing times on the order of nanoseconds, the number of two-level
defects needs to be substantially larger than the typical concentration in
glasses. We also find a finite system-size dependence of $\tau_{\phi}$, which
can be used to probe the effectiveness of surface-aggregated defects.

</DOC>
<DOC>
<DOCNO> 69820 </DOCNO>
A Dual Gauge Model with Confinement


  We reformulate the dual gauge model of the long-distance Yang-Mills theory in
terms of the two-point Wightman functions formalism. In the flux-tube scheme of
Abelian dominance and monopole condensation, the analytic expressions of both
monopole- and dual gauge boson-fields propagators are obtained. Formally, new
features of higher order quadratic equations for a monopole field are given.
Finally, we show how the rising-type potentials in the static system of color
charges are naturally derived.

</DOC>
<DOC>
<DOCNO> 40472 </DOCNO>
The CP violating phase $\gamma$ from global fit of rare charmless


  We study constraints on the CP violating phase $\gamma$ in the
Kobayashi-Maskawa model using available experimental data. We first follow the
conventional method to up date the constraint on $\gamma$ by performing a
$\chi^2$ analysis using data from $|\epsilon_K|$, $\Delta m_{B_{d,s}}$ and
$|V_{ub}/V_{cb}|$. We also include the recent information on $\sin2\beta$ in
the analysis. We obtain the best fit for $\gamma$ to be $66^\circ$ and the 95%
C.L. allowed range to be $42^\circ \sim 87^\circ$. We then develop a method to
carry out a $\chi^2$ analysis based on SU(3) symmetry using data from $B\to \pi
\pi$ and $B\to K \pi$. We also discuss SU(3) breaking effects from model
estimate. We find that present data on $B\to \pi\pi, K \pi$ can also give some
constraint on $\gamma$ although weaker than the earlier method limited by the
present experimental errors. Future improved data will provide more stringent
constraint. Finally we perform a combined fit using data from $|\epsilon_K|$,
$\Delta m_{B_{d,s}}$, $|V_{ub}/V_{cb}|$, $\sin2\beta$ and rare charmless
hadronic B decays. The combined analysis gives $\gamma=67^\circ$ for the best
fit value and $43^\circ \sim 87^\circ$ as the 95% C.L. allowed range. Several
comments on other methods to determine $\gamma$ based on SU(3) symmetry are
also provided.

</DOC>
<DOC>
<DOCNO> 122809 </DOCNO>
High-resolution X-ray spectroscopy and imaging of supernova remnant


  The observation of the supernova remnant N132D by the scientific instruments
on board the XMM-Newton satellite is presented. The X-rays from N132D are
dispersed into a detailed line-rich spectrum using the Reflection Grating
Spectrometers. Spectral lines of C, N, O, Ne, Mg, Si, S, and Fe are identified.
Images of the remnant, in narrow wavelength bands, produced by the European
Photon Imaging Cameras reveal a complex spatial structure of the ionic
distribution. While K-shell Fe emission seems to originate near the centre, all
of the other ions are observed along the shell. A high O VII / O VIII emission
ratio is detected on the northeastern edge of the remnant. This can be a sign
of hot ionising conditions, or it can reflect relatively cool gas. Spectral
fitting of the CCD spectrum suggests high temperatures in this region, but a
detailed analysis of the atomic processes involved in producing the O VII
spectral lines leads to the conclusion that the intensities of these lines
alone cannot provide a conclusive distinction between the two scenarios.

</DOC>
<DOC>
<DOCNO> 68489 </DOCNO>
SUSY Thresholds at a Muon Collider


  One of the useful features of muon colliders is the naturally narrow spread
in beam energies. Measurements of threshold cross sections then become a prime
candidate for precision measurements of particle masses, widths, and couplings
as well as determining particle spin. We describe the potential for measuring
cross sections near threshold in supersymmetric theories.

</DOC>
<DOC>
<DOCNO> 178734 </DOCNO>
On the Solution of the Number-Projected Hartree-Fock-Bogoliubov


  The numerical solution of the recently formulated number-projected
Hartree-Fock-Bogoliubov equations is studied in an exactly soluble
cranked-deformed shell model Hamiltonian. It is found that the solution of
these number-projected equations involve similar numerical effort as that of
bare HFB. We consider that this is a significant progress in the mean-field
studies of the quantum many-body systems. The results of the projected
calculations are shown to be in almost complete agreement with the exact
solutions of the model Hamiltonian. The phase transition obtained in the HFB
theory as a function of the rotational frequency is shown to be smeared out
with the projection.

</DOC>
<DOC>
<DOCNO> 10666 </DOCNO>
Reals-space renormalization group study of the anisotropic


  In this work we apply two different real-space renormalization-group (RSRG)
approaches to the anisotropic antiferromagnetic spin-1/2 Heisenberg model on
the square lattice. Our calculations allow for an approximate evaluation of the
$T$ vs. $\Delta$ phase-diagram: the results suggest the existence of a critical
value of $\Delta>0$, at which the critical temperature goes to zero, and the
presence of reentrant behavior on the critical line between the ordered and
disordered phases. This whole critical line is found to belong to the same
universality class as the Ising model. Our results are in accordance with
previous RSRG approaches but not with numerical simulations and spin-wave
calculations.

</DOC>
<DOC>
<DOCNO> 120346 </DOCNO>
Death of Stellar Baryonic Dark Matter Candidates


  The nature of the dark matter in the Universe is one of the outstanding
questions in astrophysics. In this talk, I address possible stellar baryonic
contributions to the 50-90% of our Galaxy that is made of unknown dark matter.
First I show that faint stars and brown dwarfs constitute only a few percent of
the mass of the Galaxy. Next, I show that stellar remnants, including white
dwarfs and neutron stars, are also insufficient in abundance to explain all the
dark matter of the Galaxy. High energy gamma-rays observed in HEGRA data place
the most robust constraints, $\Omega_{WD} < 3 \times 10^{-3} h^{-1}$, where $h$
is the Hubble constant in units of 100 km s$^{-1}$ Mpc$^{-1}$. Overproduction
of chemical abundances (carbon, nitrogen, and helium) provide the most
stringent constraints, $\Omega_{WD} < 2 \times 10^{-4} h^{-1}$. Comparison with
recent updates of microlensing data are also made. According to the gamma-ray
limit, all Massive Compact Halo Objects seen by the experiments (Machos) can be
white dwarfs if one takes the extreme numbers; however, from chemical
overproduction limits, NOT all Machos can be white dwarfs. Comments on recent
observations of the infrared background and of white dwarfs are also made. In
conclusion, a nonbaryonic component in the Halo seems to be required.

</DOC>
<DOC>
<DOCNO> 8388 </DOCNO>
Many-body solitons in a one-dimensional condensate of hard core bosons


  A mapping theorem leading to exact many-body dynamics of impenetrable bosons
in one dimension reveals dark and gray soliton-like structures in a toroidal
trap which is phase-imprinted. On long time scales revivals appear that are
beyond the usual mean-field theory.

</DOC>
<DOC>
<DOCNO> 7636 </DOCNO>
Escape of a chain molecule over a barrier - the kink mechanism


  We consider the generalization of the Kramers escape over a barrier problem
to the case of a long chain molecule. The problem involves the motion of a
chain molecule of $N$ segments across a region where the free energy per
segment is higher, so that it has to cross a barrier. We consider the limit
where the length of the molecule is much larger than the width of the barrier.
The width is taken to be sufficiently wide that a coninuum description is
applicable to even to the portion over the barrier. We use the Rouse model and
analyze the mechanism of crossing a barrier. There can be two dominant
mechanisms. They are: end crossing and hairpin crossing. We find the free
energy of activation for the hairpin crossing is two times that for end
crossing. In both cases, the activation energy has a square root dependence on
the temperature $T$, leading to a non-Arrhenius form for the rate. We also show
that there is a special time dependent solution of the model, which corresponds
to a kink in the chain, confined to the region of the barrier. The movement of
the polymer from one side to the other is equivalent to the motion of the kink
on the chain in the reverse direction. We also consider the translocation of
hydrophilic polypeptides across hydrophobic pores, a process that is quite
common in biological systems. Biological systems accomplish this by having a
hydrophobic signal sequence at the end that goes in first. We find that for
such a molecule, the transition state resembles a hook, and this is in
agreement with presently accepted view in cell biology.

</DOC>
<DOC>
<DOCNO> 8515 </DOCNO>
Magnetic impurities in the one-dimensional spin-orbital model


  Using one-dimensional spin-orbital model as a typical example of quantum spin
systems with richer symmetries, we study the effect of an isolated impurity on
its low energy dynamics in the gapless phase through bosonization and
renormalization group methods. In the case of internal impurities, depending on
the symmetry, the boundary fixed points can be either an open chain with a
residual spin or (and) orbital triplet left behind, or a periodic chain.
However, these two fixed points are indistinguishable in the sense that in both
cases, the lead-correction-to-scaling boundary operators (LCBO) only show
Fermi-liquid like corrections to thermodynamical quantities. (Except the
possible Curie-like contributions from the residual moments in the latter
cases.) In the case of external (Kondo) impurities, the boundary fixed points,
depending on the sign of orbital couplings, can be either an open chain with an
isolated orbital doublet due to Kondo screening or it will flow to an
intermediate fixed point with the same LCBO as that of the two-channel Kondo
problem. Comparison with the Kondo effect in one-dimensional (1D) Heisenberg
spin chain and multi-band Hubbard models is also made.

</DOC>
<DOC>
<DOCNO> 150675 </DOCNO>
Determinism and Dissipation in Quantum Gravity, Erice lecture


  Without invalidating quantum mechanics as a principle underlying the dynamics
of a fundamental theory, it is possible to ask for even more basic dynamical
laws that may yield quantum mechanics as the machinery needed for its
statistical analysis. In conventional systems such as the Standard Model for
quarks and leptons, this would lead to hidden variable theories, which are
known to be plagued by problems such as non-locality. But Planck scale physics
is so different from field theories in some flat background space-time that
here the converse may be the case: we speculate that causality and locality can
only be restored by postulating a deterministic underlying theory. A price to
be paid may be that the underlying theory exhibits dissipation of information.

</DOC>
<DOC>
<DOCNO> 8615 </DOCNO>
Quantum measurement of coherence in coupled quantum dots


  We describe the conditional and unconditional dynamics of two coupled quantum
dots when one dot is subjected to a measurement of its occupation number using
a single electron transistor (SET). The measurement is made when the bare
tunneling rate though the SET is changed by the occupation number of one of the
dots. We show that there is a difference between the time scale for the
measurement-induced decoherence between the localized states of the dots and
the time scale on which the system becomes localized due to the measurement. A
comparison between theory and current experiments is made.

</DOC>
<DOC>
<DOCNO> 122490 </DOCNO>
X-Ray Constraints on the Warm_hot Intergalactic Medium


  Three observational constraints can be placed on a warm-hot intergalactic
medium (WHIM) using \rosat PSPC pointed and survey data, the emission strength,
the energy spectrum, and the fluctuation spectrum. The upper limit to the
emission strength of the WHIM is 7.5 +/- 1.0 keV s^-1 cm^-2 sr^-1 keV^-1 in the
3/4 keV band, an unknown portion of which value may be due to our own Galactic
halo. The spectral shape of the WHIM emission can be described as thermal
emission with log T=6.42, although the true spectrum is more likely to come
from a range of temperatures. The values of emission strength and spectral
shape are in reasonable agreement with hydrodynamical cosmological models. The
autocorrelation function in the 0.44 keV < E < 1.21 keV band range, w(theta),
for the extragalactic soft X-ray background (SXRB) which includes both the WHIM
and contributions due to point sources, is less than about 0.002 for 10
arcminutes < theta < 20 arcminutes in the 3/4 keV band. This value is lower
than the Croft et al. (2000) cosmological model by a factor of about 5, but is
still not inconsistent with cosmological models. It is also found that the
normalization of the extragalactic power law component of the soft X-ray
background spectrum must be 9.5 +/- 0.9 keV s^-1 cm^-2 sr^-1 keV^-1 to be
consistent with the ROSAT All-Sky Survey.

</DOC>
<DOC>
<DOCNO> 68851 </DOCNO>
Off-forward parton distributions and Shuvaev's transformations


  We review Shuvaev's transformations, that relate off-forward parton
distributions (OFPDs) to so-called effective forward parton distributions
(EFPDs). The latter evolve like conventional forward partons. We express
nonforward amplitudes, depending on OFPDs, directly in terms of EFPDs and
construct a model for the EFPDs, which allows to consistently express them in
terms of the conventional forward parton distributions and nucleon form
factors. Our model is self-consistent for arbitrary x, xi, mu, and t.

</DOC>
<DOC>
<DOCNO> 123323 </DOCNO>
On Radiative Acceleration of Jets and Outflows from Advective Disks


  Jets and outflows are known to form out of advective accretion flows around
black holes. Hard photons from the centrifugal barrier directly hit the
electrons and deposit momentum on them. For optically thick flows such
deposition is not efficient, but for optically thin flows matter could be
accelerated to relativistic speed. In fact, even bound matter could be made
free through successive deposition. We discuss these possibilities.

</DOC>
<DOC>
<DOCNO> 119065 </DOCNO>
Reionization of the Universe by Starlight and the Photoevaporation of


  The first sources of ionizing radiation to condense out of the dark and
neutral IGM sent ionization fronts sweeping outward through their surroundings,
overtaking other condensed objects and photoevaporating them. This feedback of
universal reionization on cosmic structure formation is demonstrated here by
gas dynamical simulations, including radiative transfer, for the case of a
cosmological minihalo of dark matter and baryons exposed to an external source
of ionizing starlight, just after the passage of the global ionization front
created by the source.

</DOC>
<DOC>
<DOCNO> 9081 </DOCNO>
Thermokinetic approach of the generalized Landau-Lifshitz-Gilbert


  In order to describe the recently observed effect of current induced
magnetization reversal in magnetic nanostructures, the thermokinetic theory is
applied to a metallic ferromagnet in contact with a reservoir of spin polarized
conduction electrons. The spin flip relaxation of the conduction electrons is
described thermodynamically as a chemical reaction. The diffusion equation of
the chemical potential (or the giant magnetoresistance) and the usual
Landau-Lifshitz-Gilbert (LLG) equation are derived from the entropy variation.
The expression of the conservation laws of the magnetic moments, including spin
dependent scattering processes, leads then to the generalized LLG equation with
spin polarized current. The equation is applied to the measurements obtained on
single magnetic Ni nanowires.

</DOC>
<DOC>
<DOCNO> 70905 </DOCNO>
The Cherenkov-Compton effect in particle physics


  The two-photon production by motion of a charged particle in a medium is
considered. This process is called Cherenkov-Compton effect because the
production of photons is calculated from the Feynman diagram for the Compton
effect in a medium. This process is not forbidden in quantum electrodynamics of
dielectric media. The cross section of his process in Mandelstam variables is
calculated for pair of photons with one moving at the opposite direction to the
electron motion and the second one inside Cherenkov cone. The opposite motion
is not caused by the collision with a particle of a medium . The relation of
this process to the CERN experiments is considered.

</DOC>
<DOC>
<DOCNO> 178399 </DOCNO>
F-spin as a Partial Symmetry


  We use the empirical evidence that F-spin multiplets exist in nuclei for only
selected states as an indication that F-spin can be regarded as a partial
symmetry. We show that there is a class of non-F-scalar IBM-2 Hamiltonians with
partial F-spin symmetry, which reproduce the known systematics of collective
bands in nuclei. These Hamiltonians predict that the scissors states have good
F-spin and form F-spin multiplets, which is supported by the existing data.

</DOC>
<DOC>
<DOCNO> 100182 </DOCNO>
D-brane conformal field theory and bundles of conformal blocks


  Conformal blocks form a system of vector bundles over the moduli space of
complex curves with marked points. We discuss various aspects of these bundles.
In particular, we present conjectures about the dimensions of sub-bundles. They
imply a Verlinde formula for non-simply connected groups like PGL(n,C).
  We then explain how conformal blocks enter in the construction of conformal
field theories on surfaces with boundaries. Such surfaces naturally appear in
the conformal field theory description of string propagation in the background
of a D-brane. In this context, the sub-bundle structure of the conformal blocks
controls the structure of symmetry breaking boundary conditions.

</DOC>
<DOC>
<DOCNO> 121150 </DOCNO>
WSRT Observations of the Hubble Deep Field Region


  We present deep WSRT 1.4 GHz observations of the Hubble Deep Field region. At
the 5 sigma level, the WSRT clearly detects 85 regions of radio emission in a
10' x 10' field centred on the HDF. Eight of these regions fall within the HDF
itself, four of these are sources that have not previously been detected at 1.4
GHz, although two of these are VLA detections at 8.5GHz. The two new radio
sources detected by the WSRT are identified with relatively bright (I<21m)
moderate redshift spiral and irregular type galaxies. In the full field, the
WSRT detects 22 regions of emission that were not previously detected by the
VLA at 1.4GHz. At least two of these are associated with nearby, extended
star-forming galaxies.

</DOC>
<DOC>
<DOCNO> 116350 </DOCNO>
Jaynes-Cummings model with degenerate atomic levels


  The Jaynes-Cummings model describing the interaction of a single linearly-
polarized mode of the quantized electromagnetic field with an isolated two-
level atom is generalized to the case of atomic levels degenerate in the
projections of the angular momenta on the quantization axis, which is a usual
case in the experiments. This generalization, like the original model, obtains
the explicit solution. The model is applied to calculate the dependence of the
atomic level populations on the angle between the polarization of cavity field
mode and that of the laser excitation pulse in the experiment with one-atom
micromaser.

</DOC>
<DOC>
<DOCNO> 119488 </DOCNO>
Constraints on Cosmological Parameters from MAXIMA-1


  We set new constraints on a seven-dimensional space of cosmological
parameters within the class of inflationary adiabatic models. We use the
angular power spectrum of the cosmic microwave background measured over a wide
range of \ell in the first flight of the MAXIMA balloon-borne experiment
(MAXIMA-1) and the low \ell results from COBE/DMR. We find constraints on the
total energy density of the universe, \Omega=1.0^{+0.15}_{-0.30}, the physical
density of baryons, \Omega_{b}h^2=0.03 +/- 0.01, the physical density of cold
dark matter, \Omega_{cdm}h^2=0.2^{+0.2}_{-0.1}$, and the spectral index of
primordial scalar fluctuations, n_s=1.08+/-0.1, all at the 95% confidence
level. By combining our results with measurements of high-redshift supernovae
we constrain the value of the cosmological constant and the fractional amount
of pressureless matter in the universe to 0.45<\Omega_\Lambda<0.75 and
0.25<\Omega_{m}<0.50, at the 95% confidence level. Our results are consistent
with a flat universe and the shape parameter deduced from large scale
structure, and in marginal agreement with the baryon density from big bang
nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 117506 </DOCNO>
The Galactic Center: An Interacting System of Unusual Sources


  The region bounded by the inner tens of light years at the center of the
Milky Way contains five principal components that coexist within the central
deep gravitational potential well. These constituents are a black hole
candidate (Sgr~A*) with a mass equivalent to $2.6\pm0.2\times 10^6$ suns, a
surrounding cluster of evolved stars, a complex of young stars, molecular and
ionized gas clouds, and a powerful supernova-like remnant. The interaction of
these components is responsible for many of the phenomena occurring in this
complex and unique portion of the Galaxy. Developing a consistent picture of
the primary interactions between the components at the Galactic Center will
improve our understanding of the nature of galactic nuclei in general, and will
provide with a better defined set of characteristics of black holes. For
example, the accretion of stellar winds by Sgr A* appears to produce far less
radiation than indicated by estimates based on models of galactic nuclei.

</DOC>
<DOC>
<DOCNO> 13766 </DOCNO>
Possible Coexistence of Rotational and Ferroelectric Lattice Distortions


  The competitions between ferroelectric and rotational instabilities in
rhombohedral PZT near x = 0.5 are investigated using first principles density
functional supercell calculations. As expected, we find a strong ferroelectric
instability. However, we also find a substantial R-point rotational
instability, close to but not as deep as the ferroelectric one. This is similar
to the situation in pure PbZrO_3. These two instabilities are both strongly
pressure dependent, but in opposite directions so that lattice compression of
less than 1% is sufficient to change their ordering. Because of this, local
stress fields due to B-site cation disorder may lead to coexistence of both
types of instability are likely present in the alloy near the morphotropic
phase boundary.

</DOC>
<DOC>
<DOCNO> 83202 </DOCNO>
CoRR: A Computing Research Repository


  Discusses how CoRR was set up and some policy issues involved with setting up
such a repository.

</DOC>
<DOC>
<DOCNO> 169972 </DOCNO>
Violations of local realism by two entangled quNits are stronger than


  Tests of local realism vs quantum mechanics based on Bell's inequality employ
two entangled qubits. We investigate the general case of two entangled quNits,
i.e. quantum systems defined in an N-dimensional Hilbert space. Via a numerical
linear optimization method we show that violations of local realism are
stronger for two maximally entangled quNits (N=3,4,...,9), than for two qubits
and that they increase with N. The two quNit measurements can be experimentally
realized using entangled photons and unbiased multiport beamsplitters.

</DOC>
<DOC>
<DOCNO> 178911 </DOCNO>
On the f Sum Rule and its Extensions


  The $f$ sum rule is derived in a non-relativistic frame and connected, via
Ward Identities, to the low energy Thomson scattering. A generalisation to
isospin symmetry in the nuclear case is discussed and linked to the Meson
Exchange Currents. The extension to a fully relativistic theory is then
discussed and it is shown that the energy-weighted sum rule becomes a relation
between the particle-hole and particle-antiparticle emission. Moreover the
generalisation to isospin symmetry is also allowed and provides
non-perturbative results.

</DOC>
<DOC>
<DOCNO> 83508 </DOCNO>
Creativity and Delusions: A Neurocomputational Approach


  Thinking is one of the most interesting mental processes. Its complexity is
sometimes simplified and its different manifestations are classified into
normal and abnormal, like the delusional and disorganized thought or the
creative one. The boundaries between these facets of thinking are fuzzy causing
difficulties in medical, academic, and philosophical discussions. Considering
the dopaminergic signal-to-noise neuronal modulation in the central nervous
system, and the existence of semantic maps in human brain, a self-organizing
neural network model was developed to unify the different thought processes
into a single neurocomputational substrate. Simulations were performed varying
the dopaminergic modulation and observing the different patterns that emerged
at the semantic map. Assuming that the thought process is the total pattern
elicited at the output layer of the neural network, the model shows how the
normal and abnormal thinking are generated and that there are no borders
between their different manifestations. Actually, a continuum of different
qualitative reasoning, ranging from delusion to disorganization of thought, and
passing through the normal and the creative thinking, seems to be more
plausible. The model is far from explaining the complexities of human thinking
but, at least, it seems to be a good metaphorical and unifying view of the many
facets of this phenomenon usually studied in separated settings.

</DOC>
<DOC>
<DOCNO> 151098 </DOCNO>
Generalized Dynamics of Two Distict BPS Monopoles


  Classical and quantum dynamics of two distinct BPS monopoles in the case of
non-aligned Higgs fields are studied on the basis of the recently determined
low energy effective theory. Despite the presence of a specific potential
together with a kinetic term provided by the metric of a Taub-NUT manifold, an
O(4) or O(3,1) symmetry of the system allows for a group theoretical derivation
of the bound-state spectrum and the scattering cross section.

</DOC>
<DOC>
<DOCNO> 67839 </DOCNO>
From scalar to string confinement


  We outline a connection between scalar quark confinement, a
phenomenologically successful concept heretofore lacking fundamental
justification, and QCD. Although scalar confinement does not follow from QCD,
there is an interesting and close relationship between them. We develop a
simple model intermediate between scalar confinement and the QCD string for
illustrative purposes. Finally, we find the bound state masses of scalar,
time-component vector, and string confinement analytically through
semi-classical quantization.

</DOC>
<DOC>
<DOCNO> 117586 </DOCNO>
Thermodynamic properties of nuclear "pasta" in neutron star crusts


  Equilibrium phase diagrams for neutron star matter at subnuclear densities
are obtained at zero temperature. Spherical, rod-like and slab-like nuclei as
well as spherical and rod-like nuclear bubbles are taken into account by using
a compressible liquid-drop model. This model is designed to incorporate
uncertainties in the nuclear surface tension and in the proton chemical
potential in a gas of dripped neutrons. The resultant phase diagrams show that
for typical values of these quantities, the phases with rod-like nuclei and
with slab-like nuclei occur in the form of Coulomb lattice at densities below a
point where the system becomes uniform. Thermal fluctuations leading to
displacements of such nuclei from their equilibrium positions are considered
through explicit evaluations of their elastic constants; these fluctuations can
be effective at destroying the layered lattice of slab-like nuclei in the
temperature region typical of matter in the neutron star crust.

</DOC>
<DOC>
<DOCNO> 100604 </DOCNO>
Simple curves on hyperbolic tori


  We describe a new approach to the study of the set of all simple geodesics on
a hyperbolic punctured torus. We introduce a valuation on the first integral
homology group of the torus. This valuation associates to each homology class
the length of the unique simple geodesic in it. We show that this valuation
extends to a norm on the homology with real coefficients. We analyze the
structure of this norm, and its variation over the moduli space of punctured
tori. These results are applied to obtain sharp asymptotic estimates on the
number of simple geodesics of bounded length..

</DOC>
<DOC>
<DOCNO> 150779 </DOCNO>
A Study of Holographic Renormalization Group Flows in d=6 and d=3


  We present an explicit study of the holographic renormalization group (RG) in
six dimensions using minimal gauged supergravity. By perturbing the theory with
the addition of a relevant operator of dimension four one flows to a
non-supersymmetric conformal fixed point. There are also solutions describing
non-conformal vacua of the same theory obtained by giving an expectation value
to the operator. One such vacuum is supersymmetric and is obtained by using the
true superpotential of the theory. We discuss the physical acceptability of
these vacua by applying the criteria recently given by Gubser for the four
dimensional case and find that those criteria give a clear physical picture in
the six dimensional case as well. We use this example to comment on the role of
the Hamilton-Jacobi equations in implementing the RG. We conclude with some
remarks on AdS_4 and the status of three dimensional superconformal theories
from squashed solutions of M-theory.

</DOC>
<DOC>
<DOCNO> 9827 </DOCNO>
Theory for the reduction of products of spin operators


  In this study we show that the sum of the powers of arbitrary products of
quantum spin operators such as $(S^+)^l(S^-)^m(S^z)^n$ can be reduced by one
unit, if this sum is equal to 2S+1, S being the spin quantum number. We
emphasize that by a repeated application of this procedure \em all \em
arbitrary spin operator products with a sum of powers larger than 2S can be
replaced by a combination of spin operators with a maximum sum of powers not
larger than 2S. This transformation is exact. All spin operators must belong to
the same lattice site. By use of this procedure the consideration of single-ion
anisotropies and the investigation of the magnetic reorientation within a
Green's function theory are facilitated. Furthermore, it may be useful for the
study of time dependent magnetic properties within the ultrashort (fsec) time
domain.

</DOC>
<DOC>
<DOCNO> 71052 </DOCNO>
Probing the Infrared Structure of Gauge Theories: A Pade-Approximant


  Pade-approximant treatments of the known terms of the QCD $\beta$-function
are seen to develop possible infrared fixed point structure only if the number
of fermion flavours is sufficiently large. This flavour threshold is seen to be
between six and nine flavours, depending upon both the specific choice of
approximant as well as on the presently-unknown five-loop $\beta$-function
contribution. Below this flavour threshold, Pade approximants based upon the
QCD $\beta$-function manifest the same infrared attractor structure as that
which characterizes the exact NSVZ $\beta$-function of supersymmetric
gluodynamics. Such infrared attractor structure is also seen to characterize
Pade-approximant treatments of vector SU(N) gauge theory in the large $N$
limit, suggesting common infrared dynamics for the strong and weak phases of
this theory.

</DOC>
<DOC>
<DOCNO> 102134 </DOCNO>
Generalized Umemura polynomials


  We introduce and study generalized Umemura polynomials
$U_{n,m}^{(k)}(z,w;a,b)$ which are a natural generalization of the Umemura
polynomials $U_n(z,w;a,b)$ related to Painlev\'e $VI$ equation. We will show
that if $a=b$, or $a=0$, or $b=0$ then polynomials $U_{n,m}^{(0)}(z,w;a,b)$
generate solutions to Painlev\'e $VI$. We will describe a connection between
polynomials $U_{n,m}^{(0)}(z,w;a,0)$ and certain Umemura polynomials
$U_k(z,w;\alpha,\beta)$.

</DOC>
<DOC>
<DOCNO> 117045 </DOCNO>
Beam-based Feedback Simulations for the NLC Linac


  Extensive beam-based feedback systems are planned as an integral part of the
Next Linear Collider (NLC) control system. Wakefield effects are a significant
influence on the feedback design, imposing both architectural and algorithmic
constraints. Studies are in progress to assure the optimal selection of devices
and to refine and confirm the algorithms for the system design. We show the
results of initial simulations, along with evaluations of system response for
various conditions of ground motion and other operational disturbances.

</DOC>
<DOC>
<DOCNO> 100568 </DOCNO>
Thue equations and the method of Coleman-Chabauty


  In this paper, we prove that a Thue equation F(x,y) = h, where h is an
integer and F is a polynomial of degree n with integer coefficients and without
repeated roots, has at most 2n^3 - 2n - 3 solutions provided that the
Mordell-Weil rank of the Jacboian of the corresponding curve is less than
(n-1)(n-2)/2. The proof uses the method of Coleman-Chabauty, extended here to
apply to arbitrary regular models of curves, along with an explicit
construction of a portion of a regular model for the curve corresponding to the
Thue equation.

</DOC>
<DOC>
<DOCNO> 83118 </DOCNO>
A Compiler for Ordered Logic Programs


  This paper describes a system, called PLP, for compiling ordered logic
programs into standard logic programs under the answer set semantics. In an
ordered logic program, rules are named by unique terms, and preferences among
rules are given by a set of dedicated atoms. An ordered logic program is
transformed into a second, regular, extended logic program wherein the
preferences are respected, in that the answer sets obtained in the transformed
theory correspond with the preferred answer sets of the original theory. Since
the result of the translation is an extended logic program, existing logic
programming systems can be used as underlying reasoning engine. In particular,
PLP is conceived as a front-end to the logic programming systems dlv and
smodels.

</DOC>
<DOC>
<DOCNO> 12160 </DOCNO>
Scaling Limits for the 2D Metal-Insulator Transition at B = 0 in


  We have reexamined data on the possible two dimensional metal-insulator
transition at B=0 in Si-MOSFETs using a nonlinear regression method to extract
all scaling parameters in a single fit. By keeping track of the magnitude of
errors in the data we can use the normalized mean square deviation \chi^2 of
the fit as a quantitative measure of how well the data is compatible with
scaling. We have used this method to study electric field scaling in three
different samples. We find rather good agreement of the data with scaling in
individual fits, i.e. \chi^2's of about 1, but also rather large variations in
the fits depending on how cut-offs are introduced in the data. In particular,
we report how fitted parameters vary when we cut away data that are either far
from the critical point or at low excitation power, where temperature effects
presumably dominate. In this way we find the critical E-field exponent \beta to
vary from about 3.2 to 3.9 with considerably smaller statistical error
estimates in each fit.

</DOC>
<DOC>
<DOCNO> 68244 </DOCNO>
Theoretical Update on Rare K Decays


  We review the status of rare kaon decays, concentrating on modes with
sensitivity to short-distance flavour physics.

</DOC>
<DOC>
<DOCNO> 69577 </DOCNO>
Soft parton resummation in the current region of semi-inclusive deep


  We discuss resummation of large logarithmic terms that appear in the
cross-section of semi-inclusive DIS in the case when the final-state hadron
follows the direction of the incoming electroweak vector boson in the c.m.
frame of the vector boson and the initial-state proton.

</DOC>
<DOC>
<DOCNO> 12361 </DOCNO>
Antiferromagnetism of the 2D Hubbard Model at Half Filling: Analytic


  We introduce a local formalism to deal with the Hubbard model on a N times N
square lattice (for even N) in terms of eigenstates of number operators, having
well defined point symmetry. For U -> 0, the low lying shells of the kinetic
energy are filled in the ground state. At half filling, using the 2N-2 one-body
states of the partially occupied shell S_{hf}, we build a set of (2N-2 N-1)^{2}
degenerate unperturbed ground states with S_{z}=0 which are then resolved by
the Hubbard interaction $\hat{W}=U\sum_{r}\hat{n}_{r\ua}\hat{n}_{r\da}$. In
S_{hf} we study the many-body eigenstates of the kinetic energy with vanishing
eigenvalue of the Hubbard repulsion (W=0 states). In the S_{z}=0 sector, this
is a N times degenerate multiplet. From the singlet component one obtains the
ground state of the Hubbard model for U=0^{+}, which is unique in agreement
with a theorem by Lieb. The wave function demonstrates an antiferromagnetic
order, a lattice step translation being equivalent to a spin flip. We show that
the total momentum vanishes, while the point symmetry is s or d for even or odd
N/2, respectively.

</DOC>
<DOC>
<DOCNO> 119893 </DOCNO>
Precessing jets interacting with interstellar material as the origin for


  We present an internal shock model with external characteristics for
explaining the complicated light curves of gamma-ray bursts. Shocks produce
gamma-rays in the interaction between a precessing beam of relativistic
particles and the interstellar medium. Each time the particle beam passes the
same line of sight with the observer the inter stellar medium is pushed
outward. Subsequent interactions between the medium and the beam are delayed by
the extra distance to be traveled for the particles before the shock can form.
This results in a natural retardation and leads to an intrinsic asymmetry in
the produced light curves for gamma-ray bursts. In addition we account for the
cooling of the electron-proton plasma in the shocked region, which gives rise
to an exponential decay in the gamma-ray flux. The combination of these effects
and the precessing jet of ultra relativistic particles produces light curves
which can be directly compared with observed gamma-ray burst light curves. We
illustrate the model by fitting a number of observed gamma-ray bursts which are
hard to explain with only a precessing jet. With a genetic algorithm we are
able to fit several observed gamma-ray bursts with remarkable accuracy. We find
that for different bursts the observed fluence, assuming isotropic emission,
easily varies over four orders of magnitude from the energy generated
intrinsically.

</DOC>
<DOC>
<DOCNO> 71176 </DOCNO>
B_K in the chiral limit within the 1/Nc expansion


  I report on a recent calculation done in collaboration with E. de Rafael
(hep-ph/0006146 v3) of the invariant B_K factor of K-Kbar mixing in the chiral
limit and to next-to- leading order in the 1/Nc expansion. This calculation is,
to the best of our knowledge, the first example of a calculation of B_K in
which there is an explicit analytic cancellation of the mu renormalization
scale and the scheme dependence between the Wilson coefficient and the
corresponding kaon matrix element. I try to emphasize the ideas involved in the
approach and how the method could be applied to other physical situations,
rather than the details of the numerical analysis for which I refer the reader
to the above reference.

</DOC>
<DOC>
<DOCNO> 9602 </DOCNO>
Critical velocity in cylindrical Bose-Einstein condensates


  We describe a dramatic decrease of the critical velocity in elongated
cylindrical Bose-Einstein condensates which originates from the non-uniform
character of the radial density profile. We discuss this mechanism with respect
to recent measurements at MIT.

</DOC>
<DOC>
<DOCNO> 151670 </DOCNO>
Branes on the Brane


  We show that four-dimensional N=2 ungauged Einstein-Maxwell supergravity can
be embedded on the Randall-Sundrum 3-brane, as a consistent Kaluza-Klein
reduction of five-dimensional N=4 gauged supergravity. In particular, this
allows us to describe four-dimensional Reissner-Nordstrom black holes within
the Randall-Sundrum scenario. Using earlier results on the embedding of
five-dimensional N=4 gauged supergravity in ten dimensions, we can then
describe the four-dimensional Einstein-Maxwell supergravity on the 3-brane, and
its solutions, from a type IIB viewpoint. We also show that the minimal
ungauged supergravities in D=5 and D=6 can be consistently embedded in the
half-maximally supersymmetric gauged supergravities in D=6 and D=7
respectively. These allow us to construct solutions including BPS black holes
and strings living in "Randall-Sundrum 4-branes," and BPS self-dual strings
living in "Randall-Sundrum 5-branes." We can also lift the embeddings to
ten-dimensional massive type IIA and D=11 supergravity respectively. In
particular, we obtain a solution describing the self-dual string living in the
world-volume of an M5-brane, which can be viewed as an open membrane ending on
the M5-brane.

</DOC>
<DOC>
<DOCNO> 170125 </DOCNO>
Group-theoretical Structure of the Entangled States of N Identical


  We provide a group-theoretical classification of the entangled states of N
identical particles. The connection between quantum entanglement and the
exchange symmetry of the states of N identical particles is made explicit using
the duality between the permutation group and the simple unitary group. Each
particle has n-levels and spans the n-dimensional Hilbert space. We shall call
the general state of the particle as a qunit. The direct product of the N qunit
space is given a decomposition in terms of states with definite permutation
symmetry. The nature of fundamental entanglement of a state can be related to
the classes of partitions of the integer N. The maximally entangled states are
generated from linear combinations of the less entangled states of the direct
product space. We also discuss the nature of maximal entanglement and its
measures.

</DOC>
<DOC>
<DOCNO> 150515 </DOCNO>
Towards a Solution of the Moduli Problems of String Cosmology


  There are at least two serious moduli problems in string cosmology. The first
is the possibility that moduli dominate the energy density at the time of
nucleosynthesis. The second is that they may not find their minima all
together. After reviewing some previously proposed solutions to these problems,
we propose another: all of the moduli but the dilaton sit at points of enhanced
symmetry. The dilaton has a potential similar to those of racetrack models; it
is very massive and its dynamics do not break supersymmetry. The dilaton is
able to find the minimum of its potential because the energy is dominated by
non-zero momentum modes. This energy need not be thermal. The effective
potential for the dilaton is quite different from its flat space form. If
certain conditions are satisfied, the dilaton settles into the desired minimum;
if not, it is forced to weak coupling.

</DOC>
<DOC>
<DOCNO> 85259 </DOCNO>
Supersymmetric Quantization of Anisotropic Scalar-Tensor Cosmologies


  In this paper we show that the spatially homogeneous Bianchi type I and
Kantowski-Sachs cosmologies derived from the Brans-Dicke theory of gravity
admit a supersymmetric extension at the quantum level. Global symmetries in the
effective one-dimensional actions characterize both classical and quantum
solutions. A wide family of exact wavefunctions satisfying the supersymmetric
constraints are found. A connection with quantum wormholes is briefly
discussed.

</DOC>
<DOC>
<DOCNO> 151961 </DOCNO>
Open Descendents of U(2N) Orbifolds at Rational Radii


  We construct explicitly the open descendants of some exceptional automorphism
invariants of U(2N) orbifolds. We focus on the case N=pq, p and q prime, and on
the automorphisms of the diagonal and charge conjugation invariants that exist
for these values of N. These correspond to orbifolds of the circle with radius
R^2=2p/q. For each automorphism invariant we find two consistent Klein bottles,
and for each Klein bottle we find a complete (and probably unique) set of
boundary states. The two Klein bottles are in each case related to each other
by simple currents, but surprisingly for the automorphism of the charge
conjugation invariant neither of the Klein bottle choices is the canonical
(symmetric) one.

</DOC>
<DOC>
<DOCNO> 39688 </DOCNO>
A CsI(Tl) Scintillating Crystal Detector for the Studies of Low Energy


  Scintillating crystal detector may offer some potential advantages in the
low-energy, low-background experiments. A 500 kg CsI(Tl) detector to be placed
near the core of Nuclear Power Station II in Taiwan is being constructed for
the studies of electron-neutrino scatterings and other keV-MeV range neutrino
interactions. The motivations of this detector approach, the physics to be
addressed, the basic experimental design, and the characteristic performance of
prototype modules are described. The expected background channels and their
experimental handles are discussed.

</DOC>
<DOC>
<DOCNO> 119298 </DOCNO>
VLA radio continuum observations of a new sample of high redshift radio


  We present new deep multi-frequency radio-polarimetric images of a sample of
high redshift radio galaxies (HzRGs), having redshift between 1.7 and 4.1. The
radio data at 4.7 and 8.2 GHz were taken with the Very Large Array in the A
configuration and provide a highest angular resolution of 0.2''. Maps of total
intensity, radio spectral index, radio polarization and internal magnetic field
are presented for each source. The morphology of most objects is that of
standard FRII double radio sources, but several contain multiple hot-spots in
one or both lobes. Compared to similar samples of HzRGs previously imaged,
there is a higher fraction (29%) of compact steep spectrum sources (i.e.
sources with a projected linear size less than 20 kpc). Radio cores are
identified in about half of the sample and tend to have relatively steep
spectra (alpha < -1). Polarization is detected in all but 4 sources, with
typical polarization at 8.2 GHz of around 10-20%. The Faraday rotation can be
measured in most of the radio galaxies: the observed rotation measure (RM) of 8
radio sources exceeds 100 rad m^{-2} in at least one of the lobes, with large
gradients between the two lobes. We find no dependence of Faraday rotation with
other properties of the radio sources. If the origin of the Faraday rotation is
local to the sources, as we believe, then the intrinsic RM is more than a 1000
rad m^{-2}. Because low redshift radio galaxies residing at the center of
clusters usually show extreme RMs, we suggest that the high-z large RM sources
also lie in very dense environments. Finally, we find that the fraction of
powerful radio galaxies with extreme Faraday rotation increases with redshift,
as would be expected if their average environment tends to become denser with
decreasing cosmic epoch.

</DOC>
<DOC>
<DOCNO> 71635 </DOCNO>
A Possible Universal Treatment of the Field Strength Correlator in the


  An integral relation between two functions parametrizing the bilocal field
strength correlator within the Stochastic Vacuum Model is obtained in the
effective Abelian-projected SU(2)-theory. This relation is independent of the
concrete properties of the ensemble of vortex loops, which are present in the
theory under study. By virtue of the lattice result stating that the infrared
asymptotic behaviours of these functions should have the same functional form,
the obtained relation enables one to find these behaviours, as well as the
infrared asymptotics of the bilocal correlator of densities of the vortex
loops. Those turn out to be exponentials, decreasing at the inverse mass of the
dual vector boson, times certain polynomials in the inverse integer powers of
the distance. This result agrees with the general predictions and the existing
lattice data better than the results of previous calculations, where these
powers were found to be half-integer ones.

</DOC>
<DOC>
<DOCNO> 80889 </DOCNO>
The role of diagonalization within a diagonalization/Monte Carlo scheme


  We discuss a method called quasi-sparse eigenvector diagonalization which
finds the most important basis vectors of the low energy eigenstates of a
quantum Hamiltonian. It can operate using any basis, either orthogonal or
non-orthogonal, and any sparse Hamiltonian, either Hermitian, non-Hermitian,
finite-dimensional, or infinite-dimensional. The method is part of a new
computational approach which combines both diagonalization and Monte Carlo
techniques.

</DOC>
<DOC>
<DOCNO> 169938 </DOCNO>
An Upper Bound on the Number of States in an Unextendible Product Basis


  This paper has been withdrawn as the result is not correct.

</DOC>
<DOC>
<DOCNO> 9993 </DOCNO>
From Quantum Dynamics to the Second Law of Thermodynamics


  In quantum systems which satisfy the hypothesis of equal weights for
eigenstates [4], the maximum work principle (for extremely slow and relatively
fast operation) is derived by using quantum dynamics alone. This may be a
crucial step in establishing a firm connection between macroscopic
thermodynamics and microscopic quantum dynamics. For special models introduced
in [4,5], the derivation of the maximum work principle can be executed without
introducing any unproved assumptions.

</DOC>
<DOC>
<DOCNO> 85038 </DOCNO>
The Energy Distribution of the Bianchi Type I Universe


  We calculate the energy distribution of an anisotropic model of universe,
based on the Bianchi type I metric, in the Tolman's prescription. The energy
due to the matter plus gravitational field is equal to zero. This result agrees
with the results of Banerjee and Sen and Xulu. Also, our result supports the
viewpoint of Tryon and Rosen.

</DOC>
<DOC>
<DOCNO> 68243 </DOCNO>
Squark-Chargino Production in Polarized Gamma-Proton Collisions at TeV


  The associated production of squarks and charginos in high energy collisions
of the polarized real photons and protons is discussed. We give the cross
sections for different initial beam polarizations and the polarization
asymmetries which can be used to anticipate the masses of squarks and
charginos.

</DOC>
<DOC>
<DOCNO> 69531 </DOCNO>
Phenomenology of non-standard Z couplings in exclusive semileptonic b ->


  The rare decays $B\to K^{(*)}\ell^+\ell^-$, $B\to K^{(*)}\nu\bar\nu$ and
$B_s\to\mu^+\mu^-$ are analyzed in a generic scenario where New Physics effects
enter predominantly via $Z$ penguin contributions. We show that this
possibility is well motivated on theoretical grounds, as the $\bar sbZ$ vertex
is particularly susceptible to non-standard dynamics. In addition, such a
framework is also interesting phenomenologically since the $\bar sbZ$ coupling
is rather poorly constrained by present data. The characteristic features of
this scenario for the relevant decay rates and distributions are investigated.
We emphasize that both sign and magnitude of the forward-backward asymmetry of
the decay leptons in $\bar B\to \bar K^*\ell^+\ell^-$, ${\cal A}^{(\bar
B)}_{FB}$, carry sensitive information on New Physics. The observable ${\cal
A}^{(\bar B)}_{FB}+{\cal A}^{(B)}_{FB}$ is proposed as a useful probe of
non-standard CP violation in $\bar sbZ$ couplings.

</DOC>
<DOC>
<DOCNO> 13552 </DOCNO>
Ising models of quantum frustration


  We report on a systematic study of two dimensional, periodic, frustrated
Ising models with a quantum dynamics introduced via a transverse magnetic
field. The systems studied are the triangular and kagome lattice
antiferromagnets, fully frustrated models on the square and hexagonal
(honeycomb) lattices, a planar analog of the pyrochlore antiferromagnet, a
pentagonal lattice antiferromagnet as well as a two quasi one-dimensional
lattices that have considerable pedagogical value. All of these exhibit a
macroscopic degeneracy at T=0 in the absence of the transverse field, which
enters as a singular perturbation. We analyze these systems with a combination
of a variational method at weak fields, a perturbative Landau-Ginzburg-Wilson
(LGW) approach from large fields as well as quantum Monte Carlo simulations
utilizing a cluster algorithm. Our results include instances of quantum order
arising from classical criticality (triangular lattice) or classical disorder
(pentagonal and probably hexagonal) as well as notable instances of quantum
disorder arising from classical disorder (kagome). We also discuss the effect
of a finite temperature, as well as the interplay between longitudinal and
transverse fields--in the kagome problem the latter gives rise to a non-trivial
phase diagram with bond-ordered and bond-critical phases in addition to the
disordered phase. We also note connections to quantum dimer models and thereby
to the physics of Heisenberg antiferromagnets in short-ranged resonating
valence bond phases that have been invoked in discussions of high-temperature
superconductivity.

</DOC>
<DOC>
<DOCNO> 71682 </DOCNO>
How can one understand the lightest scalars, especially the sigma


  We discuss how the a_0(980), f_0(980), K^*_0(1430) and particularly the broad
sigma resonance can be understood within a coupled channel framework, which
includes all light two-pseudoscalar thresholds together with constraints from
Adler zeroes, flavour symmetric couplings, unitarity and physically acceptable
analyticity. All (qbar q) scalars are, when unitarized, strongly distorted by
hadronic mass shifts, and the nonstrange isoscalar state becomes a very broad
resonance, with its pole at 470-i250 MeV. We believe this is the sigma meson
required by models for spontaneous breaking of chiral symmetry. Recently this
light resonance has clearly been observed in D-> sigma pi-> 3pi by the E791
experiment at Fermilab, and we discuss how this decay channel can be predicted
in a Constituent Quark Meson Model (CQM), which incorporates heavy quark and
chiral symmetries. We also discuss the less well known phenomenon that with a
large coupling there can appear two physical resonance poles on the second
sheet although only one bare quark-antiquark state is put in. The f_0(980) and
f_0(1370) resonance poles can thus be two manifestations of the same (sbar s)
quark state. Both of these states are seen clearly in D_s-> 3pi by the E791
experiment, where (sbar s) intermediate states are expected to be dominant.

</DOC>
<DOC>
<DOCNO> 121841 </DOCNO>
Interactions and mergers at higher redshift


  In models of hierarchical structure formation, interactions and mergers at
high redshift play a key role in the formation and evolution of galaxies.
Numerical modeling and observations of nearby systems explore the detailed
physics of galaxy interactions, but applying these results to the high redshift
universe remains complicated. Evolution in the properties of galaxies over
cosmic history may lead to differences in interaction-induced star formation as
a function of redshift. High redshift interacting galaxies may be more prone to
extreme, disk-wide starburst activity than are low redshift systems. Also,
while activity in nearby clusters seems to be largely diminished, at higher
redshift we observe galaxies falling into clusters for the first time. A
variety of processes, including interactions and mergers, can drive strong
evolution in cluster galaxies at higher redshift.

</DOC>
<DOC>
<DOCNO> 11471 </DOCNO>
Introduction to the Bethe Ansatz III


  Having introduced the magnon in part I and the spinon in part II as the
relevant quasi-particles for the interpretation of the spectrum of low-lying
excitations in the one-dimensional (1D) s=1/2 Heisenberg ferromagnet and
antiferromagnet, respectively, we now study the low-lying excitations of the
Heisenberg antiferromagnet in a magnetic field and interpret these collective
states as composites of quasi-particles from a different species. We employ the
Bethe ansatz to calculate matrix elements and show how the results of such a
calculation can be used to predict lineshapes for neutron scattering
experiments on quasi-1D antiferromagnetic compounds. The paper is designed as a
tutorial for beginning graduate students. It includes 11 problems for further
study.

</DOC>
<DOC>
<DOCNO> 121888 </DOCNO>
Probing the gravitational potential of a nearby lensing cluster Abell


  The cluster Abell 2104 is one of the lowest redshift clusters (z=0.153) known
to have a gravitational lensing arc. We present detailed analysis of the
cluster properties such as the gravitational potential using the X-ray data
from ROSAT (HRI) and ASCA, as well as optical imaging and spectroscopic data
from the CFHT. The cluster is highly luminous in the X-ray with a bolometric
luminosity of Lx ~3x10^{45} ergs/s and a high gas temperature of ~10.4 keV. The
X-ray emission extending out to at least a radius of 1.46 Mpc, displays
significant substructure. The total mass deduced from the X-ray data under the
assumption of hydrostatic equilibrium and isothermal gas, is found to be
M_tot(r<1.46Mpc) ~(8.0 +/- 0.8)x10^{14} solar mass. The gas fraction within a
radius of 1.46 Mpc is ~5-10%. The cluster galaxy velocity distribution has a
dispersion of 1200 +/- 200 km/s with no obvious evidence for substructure. The
total mass within 1.46 Mpc, deduced from Jean's equation using the observed
galaxy number density distribution and velocity dispersion, is found to be
\~6.8x10^{14} solar mass to ~2.6x10^{15} solar mass marginally consistent with
the X-ray deduced total mass.

</DOC>
<DOC>
<DOCNO> 116968 </DOCNO>
High Current Proton Tests of the Fermilab Linac


  The peak current limit for the Fermilab Linac was recently studied. The
purpose was to learn what components of the present Linac can be used for the
first stage of a proposed proton driver[1]. For this application the Linac must
provide a H- beam in excess of 5000 mA-msec per pulse. The original Fermilab
Linac was designed for protons with a peak current of 75 mA and a pulse length
of four Booster turns (~10 msec). The high energy replacement was designed for
a peak current of 35 mA and a beam pulse length of 50 msec. The present H-
source cannot deliver more than ~80 mA which produces 55 mA in the Linac. Using
a proton source allows the system to be tested to currents of ~100 mA and pulse
lengths long enough to observe the effects of long pulses. This test has shown
that the present Linac can accelerate beam having a peak current up to ~85 mA
with beam loss comparable to the present Linac operation (~45 mA). The results
of the test will be presented.

</DOC>
<DOC>
<DOCNO> 100450 </DOCNO>
Equivariant embeddings into smooth toric varieties


  We characterize embeddability of algebraic varieties into smooth toric
varieties and prevarieties. Our embedding results hold also in an equivariant
context and thus generalize a well known embedding theorem of Sumihiro on
quasiprojective G-varieties. The main idea is to reduce the embedding problem
to the affine case. This is done by constructing equivariant affine conoids, a
tool which extends the concept of an equivariant affine cone over a projective
G-variety to a more general framework.

</DOC>
<DOC>
<DOCNO> 151369 </DOCNO>
Gauge Symmetry and Localized Gravity in M Theory


  We discuss the possibility of having gravity ``localized'' in dimension d in
a system where gauge bosons propagate in dimension d+1. In such a circumstance
- depending on the rate of falloff of the field strengths in d dimensions - one
might expect the gauge symmetry in d+1 dimensions to behave like a global
symmetry in d dimensions, despite the presence of gravity. Naive extrapolation
of warped long-wavelength solutions of general relativity coupled to scalars
and gauge fields suggests that such an effect might be possible. However, in
some basic realizations of such solutions in M theory, we find that this effect
does not persist microscopically. It turns over either to screening or the
Higgs mechanism at long distances in the d-dimensional description of the
system. We briefly discuss the physics of charged objects in this type of
system.

</DOC>
<DOC>
<DOCNO> 102823 </DOCNO>
An example concerning Bergman completeness


  We construct a bounded plane domain which is Bergman complete but for which
the Bergman kernel does not tend to infinity as the point approaches the
boundary.

</DOC>
<DOC>
<DOCNO> 70890 </DOCNO>
Probing Anomalous Top Quark Couplings at the Future Linear Colliders


  In terms of an effective Lagrangian we investigate the possibilities of
probing anomalous top quark couplings, $t \bar{t} H$, $\gamma t \bar{t}$, $Z t
\bar{t}$ and $tWb$ at the future linear colliders. It is found that probing
anomalous top quark couplings, $t \bar{t} H$, $\gamma t \bar{t}$, $Z t \bar{t}$
and $tWb$ at the future linear colliders. It is found that at a linear collider
with a c.m.energy $\sqrt s \sim 0.5-1.5$ TeV and a high luminosity of 10-1000
fb$^{-1}$, $e^+e^- \to t \bar{t} H$ is an ideal process in probing anomalous $t
\bar t H$ couplings. We also study in detail the effects of anomalous couplings
on $t \bar{t}$ spin correlations in the top pair production as well as the top
quark decay processes with three bases (helicity, beam line and off-diagonal
bases). Our results show that with a c. m. energy $\sqrt s \sim 0.5-1$ TeV and
a high luminosity of 1-100 fb$^{-1}$, the anomalous couplings $\gamma t
\bar{t}$, $Z t\bar{t}$ and $tWb$ may be sensitively probed.

</DOC>
<DOC>
<DOCNO> 102414 </DOCNO>
Symplectic reflection algebras, Calogero-Moser space, and deformed


  To any finite group G of automorphisms of a symplectic vector space V we
associate a new multi-parameter deformation, H_k, of the smash product of G
with the polynomial algebra on V. The algebra H_k, called a symplectic
reflection algebra, is related to the coordinate ring of a universal Poisson
deformation of the quotient singularity V/G. If G is the Weyl group of a root
system in a vector space h and V=h\oplus h^*, then the algebras H_k are
`rational' degenerations of Cherednik's double affine Hecke algebra.
  Let G=S_n, the Weyl group of g=gl_n. We construct a 1-parameter deformation
of the Harish-Chandra homomorphism from D(g)^g, the algebra of invariant
polynomial differential operators on gl_n, to the algebra of S_n-invariant
differential operators with rational coefficients on C^n. The second order
Laplacian on g goes, under the deformed homomorphism, to the Calogero-Moser
differential operator with rational potential. Our crucial idea is to
reinterpret the deformed homomorphism as a homomorphism: D(g)^g \to {spherical
subalgebra in H_k}, where H_k is the symplectic reflection algebra associated
to S_n. This way, the deformed Harish-Chandra homomorphism becomes nothing but
a description of the spherical subalgebra in terms of `quantum' Hamiltonian
reduction.
  In the classical limit k -> \infty, our construction gives an isomorphism
between the spherical subalgebra in H_\infty and the coordinate ring of the
Calogero-Moser space. We prove that all simple H_\infty-modules have dimension
n!, and are parametrised by points of the Calogero-Moser space. The algebra
H_\infty is isomorphic to the endomorphism algebra of a distinguished rank n!
vector bundle on this space.

</DOC>
<DOC>
<DOCNO> 150522 </DOCNO>
Infra-red fixed points at the boundary


  Gauged supergravities (in four and five dimensions) with eight supercharges
and with vector supermultiplets have a unique ultra-violet (UV) fixed point on
a given physical domain \cal M of the space of the scalar fields. We show that
in these models the infra-red (IR) fixed points are located on the boundary of
\cal M, where the space-time metric becomes singular.

</DOC>
<DOC>
<DOCNO> 71970 </DOCNO>
Can We Observe the Quark Gluon Plasma in Cosmic Ray Showers ?


  The possibility of detection of some features of high energy particle
interactions with detectors placed at medium depths underground through studies
on high energy muons is investigated. These muons carry information about the
early interactions occurring during the development of the hadron cascade near
the top of the atmosphere. They might reveal the effects resulting from
creation of quark gluon plasma in interactions of ultra high energy cosmic ray
iron nuclei with air nuclei.

</DOC>
<DOC>
<DOCNO> 119204 </DOCNO>
The Observational Mass Function of Loose Galaxy Groups


  We analyze the three catalogs of nearby loose groups identified by Garcia
(1993). She used a percolation and a hierarchical method, and proposed a third
group catalog defined as a combination of the two. Each catalog contains almost
500 groups. In agreement with previous works on earlier catalogs, we find that
groups can be described as collapsing systems. Their sampled size is much
larger than their expected virialized region. We compute the virial masses and
correct them by taking into account the young dynamical status. We estimate
group masses, M, for two cosmological models, a flat one with Omega_0=1 and an
open one with Omega_0=0.2. For each of the three catalogs we calculate the mass
function, MF. The number density of groups with M>9x10^{12}\msun, which is the
adopted limit of sample completeness, ranges within 1.3-1.9x10^{-3}h^3/Mpc^3
for Omega_0=1, and it is about a factor of 15% lower for Omega_0=0.2. The MFs
of the hierarchical and combined catalogs have essentially the same shape,
while the MF of the percolation catalog shows a flattening towards large
masses. However, the difference decreases if we do not consider the most
massive groups, for which reliable results come from galaxy cluster studies.
After having estimated the mass contained within the central, presumably
virialized, regions of groups by adopting a reduction in mass of 30-40%, we do
a comparison with the results coming from the virial analysis of nearby rich
clusters (Girardi et al. 1998). All three group MFs turn out to be a smooth
extrapolation of the cluster MF at M<4x10^{14}\msun, which is the completeness
limit of the cluster sample. The resulting optical virial MF of galaxy systems,
which extends over two orders of magnitude, is fitted to a Schechter expression
with a slope of about -1.5 and a characteristic mass of about 3x10^{14}\msun.

</DOC>
<DOC>
<DOCNO> 116917 </DOCNO>
Analysis of longitudinal bunching inan FEL driven two-beam accelerator


  Recent experiments [1] have explored the use of a free-electron laser (FEL)
as a buncher for a microwave two-beam accelerator, and the subsequent driving
of a standing-wave rf output cavity. Here we present a deeper analysis of the
longitudinal dynamics of the electron bunches as they are transported from the
end of the FEL and through the output cavity. In particular, we examine the
effect of the transport region and cavity aperture to filter the bunched
portion of the beam.
  [1] T. Lefevre, et. al., Phys. Rev. Lett. 84 (2000), 1188.

</DOC>
<DOC>
<DOCNO> 102781 </DOCNO>
Invitation to higher local fields, Part I, section 16: Higher class


  Author's generalization of one-dimensional class field theory to theory of
abelian totally ramified p-extensions of a complete discrete valuation field
with arbitrary non-separably p-closed residue field and its applications are
described.

</DOC>
<DOC>
<DOCNO> 11657 </DOCNO>
Multifractal Properties of Aperiodic Ising Model: role of geometric


  The role of the geometric fluctuations on the multifractal properties of the
local magnetization of aperiodic ferromagnetic Ising models on hierachical
lattices is investigated. The geometric fluctuations are introduced by
generalized Fibonacci sequences. The local magnetization is evaluated via an
exact recurrent procedure encompassing a real space renormalization group
decimation. The symmetries of the local magnetization patterns induced by the
aperiodic couplings is found to be strongly (weakly) different, with respect to
the ones of the corresponding homogeneous systems, when the geometric
fluctuations are relevant (irrelevant) to change the critical properties of the
system. At the criticality, the measure defined by the local magnetization is
found to exhibit a non-trivial F(alpha) spectra being shifted to higher values
of alpha when relevant geometric fluctuations are considered. The critical
exponents are found to be related with some special points of the F(alpha)
function and agree with previous results obtained by the quite distinct
transfer matrix approach.

</DOC>
<DOC>
<DOCNO> 99928 </DOCNO>
Solutions to WDVV from generalized Drinfeld-Sokolov hierarchies


  The dispersionless limit of generalized Drinfeld-Sokolov hierarchies
associated to primitive regular conjugacy class of Weyl group W(g) is
discussed. The map from these generalized Drinfeld - Sokolov hierarchies to
algebraic solutions to WDVV equations has been constructed. Finite dimensional
geometry behind hierarchies is studied.
 Example of g=D_4 and [w]=D_4(a_1) is considered in details and corresponding
Frobenius structure is found.

</DOC>
<DOC>
<DOCNO> 119894 </DOCNO>
A Statistical Examination of the Short Term Stability of the Upsilon


  Because of the high eccentricities (~0.3) of two of the possible planets
about the star Upsilon Andromeda, the stability of the system requires careful
study. We present results of 1000 numerical simulations which explore the
orbital parameter space as constrained by the observations. The orbital
parameters of each planet are chosen from a Gaussian error distribution, and
the resulting configuration is integrated for 1,000,000 years. We find that 84%
of these integrations are stable. Configurations in which the eccentricity of
the third planet is <0.3 are always stable, but when the eccentricity is >0.45
the system is always unstable, typically producing a close encounter between
the second and third planets. A similar exercise with the gas giants in our own
Solar System sampled with the same error distribution was performed.
Approximately 81% of these simulations were stable for 10^6 years.

</DOC>
<DOC>
<DOCNO> 70979 </DOCNO>
Effective Field Theory for Neutron-Deuteron Scattering: Higher Partial


  The phase shifts for the higher partial waves in the spin quartet and doublet
channel of nd scattering are presented at next-to-leading and
next-to-next-to-leading order in an effective field theory in which pions are
integrated out. The results agree with both phase shift analyses and potential
model calculations.

</DOC>
<DOC>
<DOCNO> 69994 </DOCNO>
Green Functions in Coordinate Space for Gauge Bosons at Finite


  The thermal Green function $D^{\mu\nu}(x)$ for free, massless gauge bosons is
computed exactly in a variety of gauges (Feynman, covariant, Coulomb, and
Landshoff-Rebhan). At large temporal separations it falls exponentially. At
large spatial separations it falls like $T/r$. In contrast, the
zero-temperature propagator falls quadratically in both regimes, being
proportional to $1/x^{2}$.

</DOC>
<DOC>
<DOCNO> 120976 </DOCNO>
A Newly Discovered SU UMa-Type Dwarf Nova, HS 1449+6415


  We report time-resolved photometric observations of the Hamburg Quasar
Survey-selected dwarf nova HS 1449+6415 (= RX J1450.5+6403) during the interval
from JD 2451672 to 2451724. During a long outburst with a duration of ~12 days,
we detected superhumps with a period of 0.0601(5) d, revealing that this star
is an SU UMa star. A short outburst which lasted 3 days was found about 40 days
after the onset of the superoutburst. From quiescence observations, we
determine an orbital period of 0.05898(2) d. The small outburst amplitude of
\~3.5 mag, the short orbital period, and the normal outburst cycle length
suggest that HS 1449+6415 is an intermediate object between ER UMa stars with
high mass-transfer rates and WZ Sge stars with very low mass-transfer rates.

</DOC>
<DOC>
<DOCNO> 83052 </DOCNO>
Poly-locality in quantum computing


  A polynomial depth quantum circuit effects, by definition a poly-local
unitary transformation of tensor product state space. It is a physically
reasonable belief [Fy][L][FKW] that these are precisely the transformations
which will be available from physics to help us solve computational problems.
The poly-locality of discrete Fourier transform on cyclic groups is at the
heart of Shor's factoring algorithm. We describe a class of poly-local
transformations, including all the discrete orthogonal wavelet transforms in
the hope that these may be helpful in constructing new quantum algorithms. We
also observe that even a rather mild violation of poly-locality leads to a
model without one-way functions, giving further evidence that poly-locality is
an essential concept.

</DOC>
<DOC>
<DOCNO> 68935 </DOCNO>
Anomalous WW-Gamma Vertex in Gamma-p Collision


  The potential of LC+HERAp based Gamma-p collider to probe WW-Gamma vertex is
presented through the discussion of sensitivity to anomalous couplings and P_T
distribution of the final quark. The limits of -0.04<\Delta\kappa<0.04 and
-0.11<\lambda<0.11 at 95% C.L. can be reached with integrated luminosity
200(1/pb). The limit for \Delta\kappa is comparable to one which is expected
from LHC. The bounds are also obtained from corresponding ep collider using
Weizsacker-Williams Approximation to compare with real photons.

</DOC>
<DOC>
<DOCNO> 123230 </DOCNO>
Classification of multifluid CP world models


  Various classification schemes exist for homogeneous and isotropic (CP) world
models, which include pressureless matter (so-called dust) and Einstein's
cosmological constant Lambda. We here classify the solutions of more general
world models consisting of up to four non-interacting fluids, each with
pressure P, energy density epsilon and an equation of state P = (gamma - 1)
epsilon with 0 <= gamma <= 2.
  In addition to repulsive fluids with negative pressure and positive energy
density, which generalize the classical repulsive (positive) Lambda component,
we consider fluids with negative energy density as well. The latter generalize
a negative Lambda component. This renders possible new types of models that do
not occur among the classical classifications of world models. Singularity-free
periodic solutions as well as further `hill-type', `hollow-type' and
`shifting-type' models are feasible.
  However, if one only allows for three components (dust, radiation and one
repulsive component) in a spatially flat universe the repulsive classical
Lambda fluid (with Lambda > 0) tends to yield the smoothest fits of the
Supernova Ia data from Perlmutter et al. (1999). Adopting the SN Ia
constraints, exotic negative energy density components can be fittingly
included only if the universe consists of four or more fluids.

</DOC>
<DOC>
<DOCNO> 11637 </DOCNO>
Rippling Instability of a Collapsing Bubble


  When a bubble of air rises to the top of a highly viscous liquid, it forms a
dome-shaped protuberance on the free surface. Unlike a soap bubble, it bursts
so slowly as to collapse under its own weight simultaneously, and folds into a
striking wavy structure. This rippling effect occurs in fact for both elastic
and viscous sheets, and a theory for its onset is formulated. The growth of the
corrugation is governed by the competition between gravitational and bending
(shearing) forces and is exhibited for a range of densities, stiffnesses
(viscosities), and sizes -- a result which arises less from dynamics than from
geometry, suggesting a wide validity. A quantitative expression for the number
of ripples is presented, together with experimental results which are in
agreement with the theoretical predictions.

</DOC>
<DOC>
<DOCNO> 13108 </DOCNO>
An Alternative Explanation on the Two Relaxation Rates in Cuprate


  Transport properties of high transition temperature (high-Tc) superconductors
have been shown to have two distinct relaxation rates. We argue that this
apparent inconsistence can be resolved with an effective carrier density n
linear in temperature T. Experimental evidences both for and against this
explanation are analyzed and we conclude that this offers a simple yet
promising scenario. Above the pseudogap temperature T* the normal state of
high-Tc cuprates is close to a Fermi liquid. It however assumes non-Fermi-
liquid behaviors below T*.

</DOC>
<DOC>
<DOCNO> 71969 </DOCNO>
Fusion rates in nuclear plasmas


  Energy and momentum of the elementary excitations become independent
variables in medium: energy and momentum statistical distributions are not
identical. The momentum distribution and not the energy distribution is
relevant for barrier penetration. The deviations of the momentum distribution
from the Maxwell-Boltzmann energy distribution can be expressed in terms of the
imaginary part of the self-energy of the quasi-particle. It is possible to
obtain an effective Tsallis' distribution for the kinetic energy. These effects
are different from static or dynamical screening and can have important
consequences for reaction rates in stars.

</DOC>
<DOC>
<DOCNO> 118386 </DOCNO>
How to Identify Pre-Protostellar Cores


  We have observed the HCO+ J=3-2 line toward 17 starless cores selected from
the list of Ward-Thompson et al. (1994). Six of these cores have line
asymmetries indicative of collapse. The excess of blue-skewed profiles over
red-skewed profiles is at least as large as that found in samples of Class 0
and early Class I sources. The observed line profiles have the same narrow
linewidths and small peak temperatures predicted for young sources in
evolutionary models, but the blue/red ratios, like those of older sources, are
higher than models predict. The infall signature also occurs over large scales,
suggesting that these cores have overall inward motions. We have divided these
starless cores into two groups based on the continuum photometry of
Ward-Thompson et al. and our HCO+ data. We find stronger HCO+ emission among
the cores detected in the submillimeter and all the blue-skewed line profiles
are in this group, supporting the suggestion of Ward-Thompson et al. that these
are the pre-protostellar cores.

</DOC>
<DOC>
<DOCNO> 118167 </DOCNO>
Binding Energy and the Fundamental Plane of Globular Clusters


  A physical description of the fundamental plane of Galactic globular clusters
is developed which explains all empirical trends and correlations in a large
number of cluster observables and provides a small but complete set of truly
independent constraints on theories of cluster formation and evolution in the
Milky Way. Within the theoretical framework of single-mass, isotropic King
models, it is shown that (1) 39 regular (non--core-collapsed) globulars with
measured core velocity dispersions share a common V-band mass-to-light ratio of
1.45 +/- 0.10, and (2) a complete sample of 109 regular globulars reveals a
very strong correlation between cluster binding energy and total luminosity,
regulated by Galactocentric position: E_b \propto (L^{2.05} r_{\rm gc}^{-0.4}).
The observational scatter about either of these two constraints can be
attributed fully to random measurement errors, making them the defining
equations of a fundamental plane for globular clusters. A third, weaker
correlation, between total luminosity and the King-model concentration
parameter, c, is then related to the (non-random) distribution of globulars on
the plane. The equations of the FP are used to derive expressions for any
cluster observable in terms of only L, r_{\rm gc}, and c. Results are obtained
for generic King models and applied specifically to the globular cluster system
of the Milky Way.

</DOC>
<DOC>
<DOCNO> 67823 </DOCNO>
On Color Superconductivity in External Magnetic Field


  We study color superconductivity in external magnetic field. We discuss the
reason why the mixing angles in color-flavor locked (CFL) and two-flavor
superconductivity (2SC) phases are different despite the fact that the CFL gap
goes to the 2SC gap for $m_s \to \infty$. Although flavor symmetry is
explicitly broken in external magnetic field, we show that all values of gaps
in their coset spaces of possible solutions in the CFL phase are equivalent in
external magnetic field.

</DOC>
<DOC>
<DOCNO> 12696 </DOCNO>
Model Calculations for Copper Clusters on Gold Electrodes


  Using the embedded-atom method, the structure of small copper clusters on
Au(111) electrodes has been investigated both by static and dynamic
calculations. By varying the size of roughly circular clusters, the edge energy
per atom is obtained; it agrees quite well with estimates based on experimental
results. Small three-dimensional clusters tend to have the shape of a pyramid,
whose sides are oriented in the directions of small surface energy. The
presence of a cluster is found to distort the underlying lattice of adsorbed
copper atoms.

</DOC>
<DOC>
<DOCNO> 121579 </DOCNO>
HI in Early-Type Galaxies


  We briefly discuss the main differences between the HI properties of luminous
and low-luminosity early-type galaxies. In luminous early-type galaxies the HI
is often irregularly distributed, but in a few cases regular HI disks, of low
surface density, are seen. In low-luminosity galaxies, the HI is more often in
a disk with high central surface densities. This suggests a different evolution
of the gas in these two groups of galaxies.

</DOC>
<DOC>
<DOCNO> 84212 </DOCNO>
Holographic Reconstruction of Spacetime and Renormalization in the


  We develop a systematic method for renormalizing the AdS/CFT prescription for
computing correlation functions. This involves regularizing the bulk on-shell
supergravity action in a covariant way, computing all divergences, adding
counterterms to cancel them and then removing the regulator. We explicitly work
out the case of pure gravity up to six dimensions and of gravity coupled to
scalars. The method can also be viewed as providing a holographic
reconstruction of the bulk spacetime metric and of bulk fields on this
spacetime, out of conformal field theory data. Knowing which sources are turned
on is sufficient in order to obtain an asymptotic expansion of the bulk metric
and of bulk fields near the boundary to high enough order so that all infrared
divergences of the on-shell action are obtained. To continue the holographic
reconstruction of the bulk fields one needs new CFT data: the expectation value
of the dual operator. In particular, in order to obtain the bulk metric one
needs to know the expectation value of stress-energy tensor of the boundary
theory. We provide completely explicit formulae for the holographic
stress-energy tensors up to six dimensions. We show that both the gravitational
and matter conformal anomalies of the boundary theory are correctly reproduced.
We also obtain the conformal transformation properties of the boundary
stress-energy tensors.

</DOC>
<DOC>
<DOCNO> 118857 </DOCNO>
X-ray Spectral Diagnostics of Gamma-Ray Burst Environments


  Recently, the detection of discrete features in the X-ray afterglow spectra
of GRB970508 and GRB970828 was reported. The most natural interpretation of
these features is that they are redshifted Fe K emission complexes. The
identification of the line emission mechanism has drastic implications for the
inferred mass of radiating material, end hence the nature of the burst site.
X-ray spectroscopy provides a direct observational constraint on these
properties of gamma-ray bursters. We briefly discuss how these constraints
arise, in the context of an application to the spectrum of GRB970508.

</DOC>
<DOC>
<DOCNO> 68744 </DOCNO>
QCD Corrections to Neutralino-Nucleon Scattering


  We calculate the dominant loop corrections from both standard and
supersymmetric QCD to the effective coupling of neutralinos to nucleons. The
potentially largest corrections come from gluino-squark loop contributions to
the Higgs boson couplings to quarks; these corrections also affect the leading
spin-independent squark exchange contribution. Ordinary QCD corrections to the
effective coupling of CP-even Higgs bosons to two gluons are also sizable. For
large $\tanb$ values, i.e. in the region of parameter space probed by current
and near-future direct Dark-Matter search experiments, the total corrections
can exceed a factor of three.

</DOC>
<DOC>
<DOCNO> 9917 </DOCNO>
Theoretical and computational study of high pressure structures in


  Recent high pressure work has suggested that elemental barium forms a high
pressure self-hosting structure (Ba IV) involving two `types' of barium atom.
Uniquely among reported elemental structures it cannot be described by a single
crystalline lattice, instead involving two interpenetrating incommensurate
lattices. In this letter we report pseudopotential calculations demonstrating
the stability and the potentially disordered nature of the `guest' structure.
Using band structures and nearly-free electron theory we relate the appearance
of Ba IV to an instability in the close-packed structure, demonstrate that it
has a zero energy vibrational mode, and speculate about the structure's
stability in other divalent elements.

</DOC>
<DOC>
<DOCNO> 68435 </DOCNO>
Fayet-Iliopoulos D-terms and anomaly mediated supersymmetry breaking


  We show that in a minimal extension of the MSSM by means of an extra U(1)
gauge group, the negative mass-squared problem characteristic of the Anomaly
Mediated Supersymmetry Breaking scenario is naturally solved by means of
Fayet-Iliopoulos D-terms. We derive a set of sum rules for the sparticle masses
which are consequences of the resulting framework.

</DOC>
<DOC>
<DOCNO> 152183 </DOCNO>
QCD Inequalities, Large $N_C$ and $\pi\pi$ Scattering Lengths


  In this short note we show that (I) in a QCD-like theory with four (rather
than two) degenerate flavors $ud u'd'$, the $\pi\pi'$ scattering length is
positive (attractive); and (II) in QCD with only two (u,d) degenerate flavors
the I=2 (say, $\pi^+\pi^+$ hadronic) scattering length is, in the large $N_C$
limit, repulsive. $\pi(\pi')$ are the lowest physical states coupling to $J^p =
\bar{u}(x)\gamma_5d(x)$ and $J^{p'} = \bar{u}'(x)\gamma_5d'(x),$ respectively.

</DOC>
<DOC>
<DOCNO> 10503 </DOCNO>
Collective oscillations in quantum rings: a broken symmetry case


  We present calculations within density functional theory of the ground state
and collective electronic oscillations in small two-dimensional quantum rings.
No spatial symmetries are imposed to the solutions and, as in a recent
contribution, a transition to a broken symmetry solution in the intrinsic
reference frame for an increasingly narrow ring is found. The oscillations are
addressed by using real-time simulation. Conspicuous effects of the broken
symmetry solution on the spectra are pointed out.

</DOC>
<DOC>
<DOCNO> 10210 </DOCNO>
Quantifying Nonstationary Radioactivity Concentration Fluctuations Near


  We analyze nonstationary $^{137}$Cs atmospheric activity concentration
fluctuations measured near Chernobyl after the 1986 disaster and find three new
results: (i) the histogram of fluctuations is well described by a log-normal
distribution, (ii) there is a pronounced spectral component with period T=1 y,
and (iii) the fluctuations are long-range correlated. These findings allow us
to quantify two fundamental statistical properties of the data - the
probability distribution and the correlation properties of the time series. We
interpret our findings as evidence that the atmospheric radionuclide
resuspension processes are tightly coupled to the surrounding ecosystems and to
large time scale weather patterns.

</DOC>
<DOC>
<DOCNO> 178865 </DOCNO>
Open charm production in relativistic nucleus-nucleus collisions


  We calculate excitation functions for open charm mesons in $Au+Au$ reactions
from AGS to RHIC energies within the HSD transport approach which is based on
string, quark, diquark ($q, \bar{q}, qq, \bar{q}\bar{q}$) and hadronic degrees
of freedom. The open charm cross sections from $pN$ and $\pi N$ reactions are
fitted to results from PYTHIA and scaled in magnitude to the available
experimental data. From our dynamical calculations we find an approximate
$m_T$-scaling for pions, kaons, $D$-mesons and $J/\Psi$ -- when discarding
final state elastic scattering of kaons and $\phi$-mesons with pions -- in
central collisions of $Au + Au$ at 160 A$\cdot$GeV (with an apparent slope of
176 MeV) without employing the assumption of a Quark-Gluon Plasma (QGP). We
demonstrate that this result is essentially due to a relative $m_T$-scaling in
$pp$ collisions at $\sqrt{s} \approx$ 17.3 GeV. At lower bombarding energies of
25 A$\cdot$GeV a suppression of $D$-mesons by a factor of $\sim$ 10 relative to
a global $m_T$-scaling with slope 143 MeV is expected. However, when
incorporating attractive $D$-meson self energies as suggested by QCD sum rules,
an approximate $m_T$-scaling is regained even at 25 A$\cdot$GeV. The effects of
$D$-meson rescattering and charmonium absorption are discussed, furthermore,
with respect to rapidity and transverse mass distributions in central
collisions of $Au + Au$ at 25, 160 A$\cdot$GeV and 21.3 A$\cdot$TeV.

</DOC>
<DOC>
<DOCNO> 151390 </DOCNO>
Casimir Energy in the Axial Gauge


  The zero-point energy of a conducting spherical shell is studied by imposing
the axial gauge via path-integral methods, with boundary conditions on the
electromagnetic potential and ghost fields. The coupled modes are then found to
be the temporal and longitudinal modes for the Maxwell field. The resulting
system can be decoupled by studying a fourth-order differential equation with
boundary conditions on longitudinal modes and their second derivatives. The
exact solution of such equation is found by using a Green-function method, and
is obtained from Bessel functions and definite integrals involving Bessel
functions. Complete agreement with a previous path-integral analysis in the
Lorenz gauge, and with Boyer's value, is proved in detail.

</DOC>
<DOC>
<DOCNO> 67880 </DOCNO>
Structure function of the nucleus in the perturbative QCD with


  Equation for the sum of BFKL pomeron fan diagrams is rederived by direct
summation and solved numerically for rapidities $y\leq 50$. At high rapidities
y>20 the resulting cross-sections for the scattering of a longitudinally
polarized $q\bar q$ pair on the nucleus cease to depend on its transverse
dimension and tend to a constant limit 0.1768 $R_A^2$, which corresponds to
scattering of a colour dipole on a black disk. Thus the unitarity is restored
and the singularity in the j plane is reduced to a simple pole at j=1.The
nuclear structure function at small x behaves as $Q^2\ln(1/x)$. The found gluon
density has a soliton-like form in the $\log k$ space: its form is close to
Gaussian, independent of rapidity, the centermoving towards higher $\log k$
with a nearly constant velocity as rapidity increases.

</DOC>
<DOC>
<DOCNO> 11013 </DOCNO>
Impurity in a d-wave superconductor: Kondo effect and STM spectra


  We present a theory for recent STM studies of Zn impurities in the
superconductor BSCCO, using insights from NMR experiments which show that there
is a net S=1/2 moment on the Cu ions near the Zn. We argue that the Kondo spin
dynamics of this moment is the origin of the low bias peak in the differential
conductance, rather than a resonance in a purely potential scattering model.
The spatial and energy dependence of the STM spectra of our model can also fit
the experiments.

</DOC>
<DOC>
<DOCNO> 102549 </DOCNO>
Conformal subalgebras of lattice vertex algebras


  In this paper we classify, under certain restrictions, all homogeneous
conformal subalgebras $\goth L$ of a lattice vertex superalgebra $V_\Lambda$
corresponding to an integer lattice $\Lambda$. We require that $\goth L$ is
graded by an almost finite root system $\Delta\subset \Lambda$ and that $\goth
L$ is stable under the action of the Heisenberg conformal algebra $\goth
H\subset V_\Lambda$. We also describe the root systems of these subalgebras.
The key ingredient of this classification is an infinite type conformal algebra
$\goth K$ obtained by the Tits-Kantor-Koeher construction from a certain Jordan
conformal triple system $\goth J$. We realize a central extension $\^{\goth K}$
of $\goth K$ inside the fermionic vertex superalgebra $V_\Z$, thus extending
the bozon-fermion correspondence.

</DOC>
<DOC>
<DOCNO> 8358 </DOCNO>
Phase ordering and roughening on growing films


  We study the interplay between surface roughening and phase separation during
the growth of binary films. Already in 1+1 dimension, we find a variety of
different scaling behaviors depending on how the two phenomena are coupled. In
the most interesting case, related to the advection of a passive scalar in a
velocity field, nontrivial scaling exponents are obtained in simulations.

</DOC>
<DOC>
<DOCNO> 102879 </DOCNO>
Parabolic bundles, products of conjugacy classes, and quantum cohomology


  We prove a condition for the existence of flat bundles on the punctured
two-sphere with prescribed holonomies around the punctures, involving
Gromov-Witten invariants of generalized flag varieties. This generalizes the
case of special unitary bundles described by S. Agnihotri and the second author
and independently P. Belkale.

</DOC>
<DOC>
<DOCNO> 100785 </DOCNO>
Epsilon constants and equivariant Arakelov Euler characteristics


  We study equivariant Arakelov-Euler characteristics of hermitian sheaves on
arithmetic varieties which support a tame action by a finite group G. The
tameness of the group action allows us to produce an equivariant Arakelov-Euler
characteristic in a particularly fine "projective" arithmetic class group. We
then show that the equivariant Arakelov-Euler characteristics of various
complexes of differentials determine the epsilon constants of the L-functions
of the motives obtained from the arithmetic variety using symplectic
representations of the group G. Our results may be viewed firstly as a higher
dimensional version of the Cassou-Nogu\`{e}s Taylor characterization of
symplectic Artin root numbers in terms of the hermitian structure of rings of
integers, and secondly as a signed equivariant version of Bloch's conductor
formula.

</DOC>
<DOC>
<DOCNO> 120228 </DOCNO>
Molecular Gas in Galaxies


  Knowledge of the molecular component of the ISM is fundamental to understand
star formation. The H2 component appears to dominate the gas mass in the inner
parts of galaxies, while the HI component dominates in the outer parts.
Observation of the CO and other lines in normal and starburst galaxies have
questioned the CO-to-H2 conversion factor, and detection of CO in dwarfs have
shown how sensitive the conversion f actor is to metallicity. Our knowledge has
made great progress in recent years, because of sensitivity and spatial
resolution improvements. Large-scale CO maps of nearby galaxies are now
available, which extend our knowledge on global properties, radial gradients,
and spiral structure of the molecular ISM. Millimetric interferometers reveal
high velocity gradients in galaxy nuclei, and formation of embedded structures,
like bars within bars. Galaxy interactions are very effective to enhance gas
concentrations and trigger starbursts. Nuclear disks or rings are frequently
observed, that concentrate the star formation activity. Since the density of
starbursting galaxies is strongly increasing with redshift, the CO lines and
the mm dust emission are a privileged tool to follow evolution of galaxies and
observe the ISM dynamics at high redshift: they could give an answer about the
debated question of the star-formation history, since many massive remote
starbursts could be dust-enshrouded.

</DOC>
<DOC>
<DOCNO> 69459 </DOCNO>
Radiative tail from the quasielastic peak in deep inelastic scattering


  The contribution of the radiative tail from the quasielastic peak to low
order radiative correction to deep inelastic scattering of polarized leptons by
polarized $^3$He was calculated within the sum rules formalism and $y$-scaling
hypothesis. Numerical analysis was carried out under the conditions of HERMES
experiment.

</DOC>
<DOC>
<DOCNO> 40490 </DOCNO>
Measurement of Orthopositronium Decay Rate Using SiO2 Powder:


  The intrinsic decay rate of orthopositronium (o-Ps) formed in SiO_2 powder
was measured using a modified method which determined the time dependence of
the pick-off annihilation rate using high-energy-resolution germanium
detectors. That is, the main systematic error due to thermalization was
accounted for and integrated into the time spectrum fitting procedure. The
averaged value was found to be lambda_(o-Ps)=7.0399+0.0020-0.0021(stat.)
+-0.0015(sys.) mu s^{-1}, which agrees well with the O(alpha^2) QED prediction;
varying 2.8-4.2 experimental standard deviations from other measurements.

</DOC>
<DOC>
<DOCNO> 9260 </DOCNO>
Self-Quenched Dynamics


  We introduce a model for the slow relaxation of an energy landscape caused by
its local interaction with a random walker whose motion is dictated by the
landscape itself. By choosing relevant measures of time and potential this
self-quenched dynamics can be mapped on to the ``True'' Self-Avoiding Walk
model. This correspondence reveals that the average distance of the walker at
time $t$ from its starting point is $R(t)\sim\log(t)^\gamma$, where
$\gamma=2/3$ for one dimension and 1/2 for all higher dimensions. Furthermore,
the evolution of the landscape is similar to that in growth models with
extremal dynamics.

</DOC>
<DOC>
<DOCNO> 72086 </DOCNO>
Pion production from a critical QCD phase


  A theoretical scheme which relates multiparticle states generated in
ultrarelativistic nuclear collisions to a QCD phase transition is considered in
the framework of the universality class provided by the 3-D Ising model. Two
different evolution scenarios for the QGP system are examined. The statistical
mechanics of the critical state is accounted for in terms of (critical) cluster
formation consistent with suitably cast effective action functionals, one for
each considered type of expansion. Fractal properties associated with these
clusters, characterizing the density fluctuations near the QCD critical point,
are determined. Monte-Carlo simulations are employed to generate events,
pertaining to the total system, which correspond to signals associated with
unconventional sources of pion production.

</DOC>
<DOC>
<DOCNO> 83451 </DOCNO>
Extension Language Automation of Embedded System Debugging


  Embedded systems contain several layers of target processing abstraction.
These layers include electronic circuit, binary machine code, mnemonic assembly
code, and high-level procedural and object-oriented abstractions. Physical and
temporal constraints and artifacts within physically embedded systems make it
impossible for software engineers to operate at a single layer of processor
abstraction. The Luxdbg embedded system debugger exposes these layers to
debugger users, and it adds an additional layer, the extension language layer,
that allows users to extend both the debugger and its target processor
capabilities. Tcl is Luxdbg's extension language. Luxdbg users can apply Tcl to
automate interactive debugging steps, to redirect and to interconnect target
processor input-output facilities, to schedule multiple processor execution, to
log and to react to target processing exceptions, and to automate target system
testing. Inclusion of an extension language like Tcl in a debugger promises
additional advantages for distributed debugging, where debuggers can pass
extension language expressions across computer networks.

</DOC>
<DOC>
<DOCNO> 116247 </DOCNO>
Wave Essence of Particles


  We state several ideas based on the view-point of particle behaviour of
matter to explain wave character of photon and elementary particles. By using
Newton's suggestion of light ray, we clarify integrally the behaviour of light
``wave''. And ``wave'' character of particles is also explained by the
view-point of particle.

</DOC>
<DOC>
<DOCNO> 119109 </DOCNO>
The orbital evolution of planets in disks


  The orbital parameters of the observed extrasolar planets differ strongly
from those of our own solar system. The differences include planets with high
masses, small semi-major axis and large eccentricities. We performed numerical
computations of embedded planets in disks and follow their mass growth and
orbital evolution over several thousand periods.
  We find that planets do migrate inwards on timescales of about $10^5$ years
on nearly circular orbits, during which they may grow up to about 5 Jupiter
masses. The interaction of the disk with several planets may halt the migration
process and lead to a system similar to the solar planetary system.

</DOC>
<DOC>
<DOCNO> 151596 </DOCNO>
Statistical properties of classical gravitating particles in (2+1)


  We report the statistical properties of classical particles in (2+1) gravity
as resulting from numerical simulations. Only particle momenta have been taken
into account. In the range of total momentum where thermal equilibrium is
reached, the distribution function and the corresponding Boltzmann entropy are
computed. In the presence of large gravity effects, different extensions of the
temperature turn out to be inequivalent, the distribution function has a power
law high-energy tail and the entropy as a function of the internal energy
presents a flex. When the energy approaches the open universe limit, the
entropy and the mean value of the particle kinetic energy seem to diverge.

</DOC>
<DOC>
<DOCNO> 83338 </DOCNO>
Tagger Evaluation Given Hierarchical Tag Sets


  We present methods for evaluating human and automatic taggers that extend
current practice in three ways. First, we show how to evaluate taggers that
assign multiple tags to each test instance, even if they do not assign
probabilities. Second, we show how to accommodate a common property of manually
constructed ``gold standards'' that are typically used for objective
evaluation, namely that there is often more than one correct answer. Third, we
show how to measure performance when the set of possible tags is
tree-structured in an IS-A hierarchy. To illustrate how our methods can be used
to measure inter-annotator agreement, we show how to compute the kappa
coefficient over hierarchical tag sets.

</DOC>
<DOC>
<DOCNO> 100571 </DOCNO>
On the quantum model of gravitational electrodynamics


  It is shown that application of dynamic flows concept in 4-dimensional
Euclidean space makes possible to form Minkowski space and to formulate the
generalized variational problem of electrodynamics and gravi- dynamics. It is
shown that 1-dimensional (cylindrical) factorization of 4-dimensional Euclidean
space provides a quantization of ths model.

</DOC>
<DOC>
<DOCNO> 11437 </DOCNO>
Multi-phonon Resonant Raman Scattering Predicted in LaMnO3 from the


  Resonant behavior of the Raman process is predicted when the laser frequency
is close to the orbital excitation energy of LaMnO3 at 2 eV. The incident
photon creates a vibrationally excited self-trapped ``orbiton'' state from the
orbitally-ordered Jahn-Teller (JT) ground state. Trapping occurs by local
oxygen rearrangement. Then the Franck-Condon mechanism activates multiphonon
Raman scattering. The amplitude of the $n$-phonon process is first order in the
electron-phonon coupling $g$. The resonance occurs {\it via} a dipole forbidden
$d$ to $d$ transition. We previously suggested that this transition (also seen
in optical reflectivity) becomes allowed because of asymmetric oxygen
fluctuations. Here we calculate the magnitude of the corresponding matrix
element using local spin-density functional theory. This calculation agrees to
better than a factor of two with our previous value extracted from experiment.
This allows us to calculate the absolute value of the Raman tensor for
multiphonon scattering. Observation of this effect would be a direct
confirmation of the importance of the JT electron-phonon term and the presence
of self-trapped orbital excitons, or ``orbitons''.

</DOC>
<DOC>
<DOCNO> 116781 </DOCNO>
Measurement of the temporal response of ferroelectric cathodes


  Ferroelectric ceramics are tested as photocathodes at INFN Frascati
Laboratories. In order to characterize them for use in linac injectors it is
important to measure the temporal shape of the emitted current. With a duration
of the laser pulse of 25 ps, the required resolution is a few ps. An apparatus
has been set up for the purpose, consisting of a 30 kV electron gun, a
microwave deflecting cavity which translates the temporal distribution of the
electron bunch into a spatial one, a fluorescent screen on which the deflected
beam traces a sector of a circle and various focusing and charge measuring
items. The image on the screen is detected via a CCD camera and a frame
grabber. We describe the performance of the apparatus and some preliminary
temporal distribution measurements.

</DOC>
<DOC>
<DOCNO> 178822 </DOCNO>
Uncertainties in the eta-Nucleon Scattering Length and Effective Range


  The coupled eta-N, pi-N, gamma-N system is described by a K-matrix method.
The parameters in this model are adjusted to get an optimal fit to pi-N --->pi-
N$, pi-N --->eta-N$, gamma-N--->pi-N and gamma-N --->eta-N data in an energy
range of about 100MeV or so each side of the eta threshold. The outcome is the
appearance of two solutions one which has an eta-nucleon scattering length (a)
of about 1.0 fm and a second with a~0.2fm. However, the second solution has an
unconventional non-Lorentian form for the T-matrix in the region of the
1535(20)MeV and 1650(30)MeV S-wave pi-N resonances.

</DOC>
<DOC>
<DOCNO> 71831 </DOCNO>
Basics of QCD Perturbation Theory: TASI 2000


  This is an introduction to the use of QCD perturbation theory, emphasizing
generic features of the theory that enable one to separate short-time and
long-time effects. I also cover some important classes of applications:
electron-positron annihilation to hadrons, deeply inelastic scattering, and
hard processes in hadron-hadron collisions.

</DOC>
<DOC>
<DOCNO> 9819 </DOCNO>
On Fractional Diffusion and its Relation with Continuous Time Random


  Time evolutions whose infinitesimal generator is a fractional time derivative
arise generally in the long time limit. Such fractional time evolutions are
considered here for random walks. An exact relationship is given between the
fractional master equation and a separable continuous time random walk of the
Montroll-Weiss type. The waiting time density can be expressed using a
generalized Mittag-Leffler function. The first moment of the waiting density
does not exist.

</DOC>
<DOC>
<DOCNO> 39846 </DOCNO>
Implications of light-quark admixtures on charmonium decays into meson


  We argue that charmonium decays into meson pairs fall into two distinct
classes: one that is under control of perturbative QCD and another one that is
governed by a soft mechanism. We concentrate on a systematic analysis of J/Psi
(Psi') decays into a light pseudoscalar and a light vector meson and eta(c)
decays into a pair of light vector mesons. These processes belong to the second
class and are characterized by non-conserved hadronic helicity. It is assumed
that, in these cases, the charmonium state decays dominantly through a
light-quark Fock component by a soft mechanism which is characteristic of
OZI-rule allowed strong decays. Estimating the light-quark admixture by meson
mixing, we obtain a reasonable description of the branching ratios for these
processes.

</DOC>
<DOC>
<DOCNO> 99323 </DOCNO>
Matrix Factorization for an SO(2) Spinning Top and Related Problems


  We study the matrix factorization problem associated with an SO(2) spinning
top by using the algebro-geometric approach. We derive the explicit expressions
in terms of Riemann theta functions and discus some related problems including
a non-compact extension and the case when the Lax matrix contains higher-order
powers of the spectral parameter.

</DOC>
<DOC>
<DOCNO> 69932 </DOCNO>
New constraints from Haverah Park data on the photon and iron fluxes of


  Using data from inclined events ($60^{\circ}<\theta<80^{\circ}$) recorded by
the Haverah Park shower detector, we show that above 10^19 eV less than 30% of
the primary cosmic rays can be photons or iron nuclei at the 95% confidence
level. Above 4 10^19 eV less than 55% of the cosmic rays can be photonic at the
same confidence level. These limits place important constraints on some models
of the origin of ultra high energy cosmic rays. Details of two new events above
10^20 eV are reported.

</DOC>
<DOC>
<DOCNO> 119788 </DOCNO>
Constraining the cosmic equation of state from old galaxies at high


  New limits on the cosmic equation of state are derived from age measurements
of three recently reported old high redshift galaxies (OHRG). The results are
based on a flat FRW type cosmological model driven by nonrelativistic matter
plus a smooth component parametrized by its equation of state $p_{x} =
\omega\rho_{x}$ ($\omega \geq -1$). The range of $\omega$ is strongly dependent
on the matter density parameter. For $\Omega_{M} \sim 0.3$, as indicated from
dynamical measurements, the age estimates of the OHRG restricts the cosmic
parameter to $\omega\leq - 0.27$. However, if $\Omega_{M}$ is the one suggested
by some studies of field galaxies, i.e, $\Omega_{M} \simeq 0.5$, only a
cosmological constant ($\omega=-1$) may be compatible with these data.

</DOC>
<DOC>
<DOCNO> 178643 </DOCNO>
About the parity-non-conserving asymmetry in n+p--->d+gamma


  The parity-non-conserving (pnc) asymmetry in \vec{n} + p \to d+\gamma at
thermal energies has recently been calculated using effective field-theory
methods. A comparison of this calculation with much more elaborate calculations
performed in the 70's is made. This allows one to assess the validity of this
new approach as presently used. It is found to overshoot the almost exact
calculations by a factor close to 2 for the contribution involving the ^3S_1
component of both the initial and final states. This is much larger than
anticipated by the authors. This discrepancy is analyzed and found to originate
from the over-simplified description of the deuteron and capture states which
underlies the new approach. The claim that earlier determinations of the sign
would be in error is also examined. It is found that the sign discrepancy is
most probably due, instead, to the fact that the pion-nucleon interaction
referred to by the authors corresponds to a parity-non-conserving potential
with a sign opposite to what is currently used. Some estimates and constraints
relative to the pnc piNN coupling, h^1_{\pi}, which the above asymmetry is
dependent on, are reviewed. Further details are given in an Appendix.

</DOC>
<DOC>
<DOCNO> 9749 </DOCNO>
Presence of energy flux in quantum spin chains: An experimental


  Using the XXZ model for the description of one-dimensional magnetic materials
we show that an energy flux, j_E, produces a shift, dk (j_E)^0.5, in the
characteristic wavenumber of the spin-spin correlations. We estimate dk for a
realistic experimental setup and find that it is measurable in inelastic
neutron scattering experiments.

</DOC>
<DOC>
<DOCNO> 39754 </DOCNO>
Hard-Photon Production and Tests of QED at LEP


  The total and differential cross sections of the process e+e- -> n gamma with
n >= 2 are measured using data collected by the L3 experiment at centre-of-mass
energies of \sqrt{s}=183 and 189 GeV. The results are in agreement with the
Standard Model expectations. Limits are set on deviations from QED, contact
interaction cut-off parameters and masses of excited electrons.

</DOC>
<DOC>
<DOCNO> 152483 </DOCNO>
On manifest SU(4) invariant superstring action in AdS(5) x S(5)


  We discuss manifestly SL(2,C)x SU(4) and kappa invariant superstring action
in AdS(5) x S(5) background in the framework of Green-Schwarz formulation. The
action is formulated in terms of 16 Poincare fermionic coordinates which
through AdS/CFT correspondence should represent N=4 SYM superspace and 16
superconformal fermionic coordinates. The action is also manifestly invariant
with respect to the usual N=4 Poincare superalgebra transformations.
kappa-symmetry gauge fixing and the derivation of light-cone gauge action is
simplified.

</DOC>
<DOC>
<DOCNO> 9201 </DOCNO>
Spectra, Pseudospectra, and Localization for Random Bidiagonal Matrices


  There has been much recent interest, initiated by work of the physicists
Hatano and Nelson, in the eigenvalues of certain random non-Hermitian periodic
tridiagonal matrices and their bidiagonal limits. These eigenvalues cluster
along a "bubble with wings" in the complex plane, and the corresponding
eigenvectors are localized in the wings, delocalized in the bubble. Here, in
addition to eigenvalues, pseudospectra are analyzed, making it possible to
treat the non-periodic analogues of these random matrix problems. Inside the
bubble, the resolvent norm grows exponentially with the dimension. Outside, it
grows subexponentially in a bounded region that is the spectrum of the
infinite-dimensional operator. Localization and delocalization correspond to
resolvent matrices whose entries exponentially decrease or increase,
respectively, with distance from the diagonal. This article presents theorems
that characterize the spectra, pseudospectra, and numerical range for the four
cases of finite bidiagonal matrices, infinite bidiagonal matrices ("stochastic
Toeplitz operators"), finite periodic matrices, and doubly infinite bidiagonal
matrices ("stochastic Laurent operators").

</DOC>
<DOC>
<DOCNO> 9789 </DOCNO>
Quantum nucleation in ferromagnets with tetragonal and hexagonal


  The phenomenon of quantum nucleation is studied in a ferromagnet in the
presence of a magnetic field at an arbitrary angle. We consider the
magnetocrystalline anisotropy with tetragonal symmetry and that with hexagonal
symmetry, respectively. By applying the instanton method in the
spin-coherent-state path-integral representation, we calculate the dependence
of the rate of quantum nucleation and the crossover temperature on the
orientation and strength of the field for a thin film and for a bulk solid. Our
results show that the rate of quantum nucleation and the crossover temperature
depend on the orientation of the external magnetic field distinctly, which
provides a possible experimental test for quantum nucleation in nanometer-scale
ferromagnets.

</DOC>
<DOC>
<DOCNO> 69738 </DOCNO>
Ultrahigh Energy Neutrinos and the Highest Energy Cosmic Rays


  It has been suggested that the characteristic energy of string models may be
considerably lower than the observed Planck mass. In such schemes, the
unification of interactions takes place around the string scale, perhaps as low
as a few tens of TeV. Consequently, at energies above the string scale,
neutrinos acquire interactions comparable in strength to strong interactions.
While they can propagate through the CMBR essentially uninhibited, in
interactions with nuclei in the atmosphere they induce air showers comparable
to proton induced ones. We conjecture that air showers above the
Greisen-Zatsepin-Kuzmin (GZK) cutoff in the cosmic radiation are induced by
such neutrinos. A Monte Carlo simulation shows that neutrino induced
"anomalous" showers are virtually indistinguishable from proton induced ones on
an event-by event basis. However, given sufficient statistics in detectors
(HiRes, OWL, Auger etc.), the post-GZK showers are expected to exhibit
characteristics in the fluctuation pattern allowing a distinction between
proton and neutrino induced showers.

</DOC>
<DOC>
<DOCNO> 150813 </DOCNO>
Quantization Ambiguity and Supersymmetric Ground State Wave Functions


  Supersymmetric ground state wave functions of a model of supersymmetric
quantum mechanics on $S^1$ (supersymmetric simple pendulum) are studied.
Supersymmetry can be broken due to the existence of an undetermined parameter,
which is interpreted as a gauge field and appears as a firm consequence of
quantization on a space with a nontrivial topology such as $S^1$. The breaking
does not depend on the leading term of the superpotential, contrary to the
usual case. The mechanism of supersymmetry breaking is similar to that through
boundary conditions of fields in supersymmetric quantum field theory on
compactified space. The supersymmetric harmonic oscillator is realized in the
limit of the infinite radius of $S^1$ with the strength of the oscillator being
constant.

</DOC>
<DOC>
<DOCNO> 71278 </DOCNO>
Improved Resummations for the Thermodynamics of the Quark-Gluon Plasma


  Two recent attempts for overcoming the poor convergence of the perturbation
expansion of the thermodynamic potentials of QCD are discussed: an HTL-adaption
of ``screened perturbation theory'' and approximately self-consistent HTL
resummations in the two-loop entropy.

</DOC>
<DOC>
<DOCNO> 8446 </DOCNO>
Extensive Chaos in the Nikolaevskii Model


  We carry out a systematic study of a novel type of chaos at onset ("soft-mode
turbulence") based on numerical integration of the simplest one dimensional
model. The chaos is characterized by a smooth interplay of different spatial
scales, with defect generation being unimportant. The Lyapunov exponents are
calculated for several system sizes for fixed values of the control parameter
$\epsilon$. The Lyapunov dimension and the Kolmogorov-Sinai entropy are
calculated and both shown to exhibit extensive and microextensive scaling. The
distribution functional is shown to satisfy Gaussian statistics at small
wavenumbers and small frequency.

</DOC>
<DOC>
<DOCNO> 102213 </DOCNO>
Regularity of a free boundary with application to the Pompeiu problem


  In the unit ball B(0,1), let $u$ and $\Omega$ (a domain in $\R$) solve the
following overdetermined problem: $$\Delta u =\chi_\Omega\quad \hbox{in}
B(0,1), \qquad 0 \in \partial \Omega, \qquad u=|\nabla u |=0 \quad \hbox{in}
B(0,1)\setminus \Omega,$$ where $\chi_\Omega$ denotes the characteristic
function, and the equation is satisfied in the sense of distributions. If the
complement of $\Omega$ does not develop cusp singularities at the origin then
we prove $\partial \Omega$ is analytic in some small neighborhood of the
origin. The result can be modified to yield for more general divergence form
operators. As an application of this, then, we obtain the regularity of the
boundary of a domain without the Pompeiu property, provided its complement has
no cusp singularities.

</DOC>
<DOC>
<DOCNO> 102049 </DOCNO>
Towers of function fields with extremal properties


  Certain towers of function fields with complete splitting of rational places
at each stage are constructed. Also, families oof towers with positive N/g
ratios are described.

</DOC>
<DOC>
<DOCNO> 119540 </DOCNO>
New Insights Into The Narrow-Line Seyfert 1 Phenomenon


  I briefly review the X/UV absorber models and show that the observations of
NLS1s are generally consistent with the models. The covering factor of
absorbers in NLS1s is likely to be high and there is some evidence of
super-solar metallicities. I argue that NLS1s may be active galaxies in the
early stage of their evolution and as such, may be low luminosity, low redshift
analogues of the high redshift quasars. NLS1s may reside in rejuvenated
gas-rich galaxies. I also propose that the high Fe II emission in NLS1s may be
a direct consequence of their large accretion rate and so a collisional
ionization origin of FeII is favored.

</DOC>
<DOC>
<DOCNO> 70520 </DOCNO>
Weak form factors for heavy meson decays


  We calculate the form factors for weak decays of $B_{(s)}$ and $D_{(s)}$
mesons to light pseudoscalar and vector mesons within a relativistic dispersion
approach based on the constituent quark picture.
  This approach gives the form factors as relativistic double spectral
representations in terms of the wave functions of the initial and final mesons.
The form factors have the correct analytic properties and satisfy general
requirements of nonperturbative QCD in the heavy quark limit. The effective
quark masses and meson wave functions are determined by fitting the quark model
parameters to lattice QCD results for the $B\to \rho$ transition form factors
at large momentum transfers and to the measured $D\to (K,K^*)l\nu$ decay rates.
This allows us to predict numerous form factors for all kinematically
accessible $q^2$ values.

</DOC>
<DOC>
<DOCNO> 174486 </DOCNO>
Poincare' Covariant Current Operator and Elastic Electron-Deuteron


  The deuteron electromagnetic form factors, $A(Q^2)$ and $B(Q^2)$, and the
tensor polarization $T_{20}(Q^2)$, are unambiguously calculated within the
front-form relativistic Hamiltonian dynamics, by using a novel current, built
up from one-body terms, which fulfills Poincar\'e, parity and time reversal
covariance, together with Hermiticity and the continuity equation. A
simultaneous description of the experimental data for the three deuteron form
factors is achieved up to $Q^2 < 0.4 (GeV/c)^2$. At higher momentum transfer,
different nucleon-nucleon interactions strongly affect $A(Q^2)$, $B(Q^2)$, and
$T_{20}(Q^2)$ and the effects of the interactions can be related to $S$-state
kinetic energy in the deuteron. Different nucleon form factor models have huge
effects on $A(Q^2)$, smaller effects on $B(Q^2)$ and essentially none on
$T_{20}(Q^2)$.

</DOC>
<DOC>
<DOCNO> 69889 </DOCNO>
Spin effects in B_c -> X_cc + \pi (\rho) decays


  The two-particle hadronic decays of B_c meson into S-wave and P-wave
charmonium states X_cc are considered in the framework of hard gluon exchange
model. It is shown that decay width of B_c meson into S-wave charmonium states
doubly exceeds one for S-wave states. In compare with the previous estimations
we predict the enhancement by 8 % the branching ratio for the B_c decays into
J/psi in the two-particle hadronic decays via the contribution of the radiative
decays of P-wave states in the cascade processes.

</DOC>
<DOC>
<DOCNO> 68618 </DOCNO>
$K_{\ell 4}$ Form-Factors and $\pi$-$\pi$ Scattering


  The $F$ and $G$ form-factors of $K_{\ell4}$ and the quark condensates are
calculated to ${\cal O}(p^6)$ in Chiral Perturbation Theory (CHPT). Full
formulas are presented as much as possible. A full refit of most of the ${\cal
O}(p^4)$ CHPT parameters is done with a discussion of all inputs and underlying
assumptions. We discuss the consequences for the vacuum expectation values,
decay constants, pseudoscalar masses and $\pi$-$\pi$ scattering.

</DOC>
<DOC>
<DOCNO> 14102 </DOCNO>
Superfluidity versus Bloch oscillations in confined atomic gases


  We study the superfluid properties of (quasi) one-dimensional bosonic atom
gases/liquids in traps with finite geometries in the presence of strong quantum
fluctuations. Driving the condensate with a moving defect we find the
nucleation rate for phase slips using instanton techniques. While phase slips
are quenched in a ring resulting in a superfluid response, they proliferate in
a tube geometry where we find Bloch oscillations in the chemical potential.
These Bloch oscillations describe the individual tunneling of atoms through the
defect and thus are a consequence of particle quantization.

</DOC>
<DOC>
<DOCNO> 68798 </DOCNO>
Exclusive semileptonic rare decays $B ->_ ($K,K^*) \ell^+ \ell^- in


  The invariant mass spectrum, forward-backward asymmetry, and lepton
polarizations of the exclusive processes $B\to K(K^*)\ell^+ \ell^-, \ell=\mu,
\tau$ are analyzed under supersymmetric context. Special attention is paid to
the effects of neutral Higgs bosons (NHBs). Our analysis shows that the
branching ratio of the process $\bkm$ can be quite largely modified by the
effects of neutral Higgs bosons and the forward-backward asymmetry would not
vanish. For the process $\bksm$, the lepton transverse polarization is quite
sensitive to the effects of NHBs, while the invariant mass spectrum,
forward-backward asymmetry, and lepton longitudinal polarization are not. For
both $\bkt$ and $\bkst$, the effects of NHBs are quite significant. The partial
decay widths of these processes are also analyzed, and our analysis manifest
that even taking into account the theoretical uncertainties in calculating weak
form factors, the effects of NHBs could make SUSY shown up.

</DOC>
<DOC>
<DOCNO> 85291 </DOCNO>
A new approach to quantum gravity: an overview


  We quantise General Relativity for a class of energy-momentum-stress tensors.

</DOC>
<DOC>
<DOCNO> 123018 </DOCNO>
First Intrinsic Anisotropy Observations with the Cosmic Background


  We present the first results of observations of the intrinsic anisotropy of
the cosmic microwave background radiation with the Cosmic Background Imager
from a site at 5080 m altitude in northern Chile. Our observations show a sharp
decrease in C_l in the range l=400 - 1500. The broadband amplitudes we have
measured are deltaT(band) = 58.7 (-6.3, +7.7) microK for l = 603 (-166, +180)
and 29.7 (-4.2, +4.8) microK for l = 1190 (-224, +261), where these are
half-power widths in l. Such a decrease in power at high l is one of the
fundamental predictions of the standard cosmological model, and these are the
first observations which cover a broad enough l range to show this decrease in
a single experiment. The C_l we have measured enable us to place limits on the
density parameter, Omega(tot) <= 0.4 or $Omega(tot) >= 0.7 (90% confidence).

</DOC>
<DOC>
<DOCNO> 83347 </DOCNO>
Processing Self Corrections in a speech to speech system


  Speech repairs occur often in spontaneous spoken dialogues. The ability to
detect and correct those repairs is necessary for any spoken language system.
We present a framework to detect and correct speech repairs where all relevant
levels of information, i.e., acoustics, lexis, syntax and semantics can be
integrated. The basic idea is to reduce the search space for repairs as soon as
possible by cascading filters that involve more and more features. At first an
acoustic module generates hypotheses about the existence of a repair. Second a
stochastic model suggests a correction for every hypothesis. Well scored
corrections are inserted as new paths in the word lattice. Finally a lattice
parser decides on accepting the rep air.

</DOC>
<DOC>
<DOCNO> 100405 </DOCNO>
A Possible Origin of Logic


  An origin is often an intriguing issue. It becomes doubly intriguing when the
logical form of thinking is considered. In this paper we will investigate
exactly that: we will conjecture on the origin of basic instruments of logical
thinking.
  As the starting point we consider a very general case of a subject
interacting with an environment. The subject might often have a choice of
actions to take. Additionally, it is of fundamental importance that as a rule
the subject's internal representations of (beliefs about) the environment are
inaccurate.
  Beginning with this very general schema we will eventually arrive at a
possible mechanism of how Logic could have emerged. Our reasoning will be
supported with some in-depth case studies.

</DOC>
<DOC>
<DOCNO> 71411 </DOCNO>
Neutrinos from Gamma Ray Bursts


  The observed fluxes of cosmic rays and gamma rays are used to infer the
maximum allowed high-energy neutrino flux allowed for Gamma Ray Bursts (GRBs),
following Mannheim, Protheroe, and Rachen (2000). It is shown that if GRBs
produce the ultrahigh-energy cosmic rays, they should contribute (a) at least
10% of the extragalactic gamma ray background between 3 MeV and 30 GeV,
contrary to their observed energy flux which is only a minute fraction of this
flux, and (b) a cumulative neutrino flux a factor of 20 below the AMANDA
(Neutrino 2000) limit on isotropic neutrinos. This could have two implications,
either GRBs do not produce the ultrahigh energy cosmic rays or that the GRBs
are strongly beamed and emit most of their power at energies well above 100 GeV
implausibly increasing the energy requirements, but consistent with the
marginal detections of a few low-redshift GRBs by MILAGRITO, HEGRA-AIROBICC,
and the Tibet-Array. All crucial measurements to test the models will be
available in the next few years. These are measurements of (i) high-energy
neutrinos with AMANDA-ICECUBE or an enlarged ANTARES/NESTOR ocean detector,
(ii) GRB redshifts from HETE-2 follow-up studies, and (iii) GRB spectra above
10 GeV with low-threshold imaging air Cherenkov telescopes such as MAGIC and
the space telescopes AGILE and GLAST.

</DOC>
<DOC>
<DOCNO> 72109 </DOCNO>
Time-like Extra Dimensions without Tachyons or Ghosts


  Some time ago Dvali, Gabadadze and Senjanovic (hep-ph/9910207) discussed
brane world scenarios with time-like extra dimensions. In this paper we
construct a solitonic 3-brane solution in the 5-dimensional
Einstein-Hilbert-Gauss-Bonnet theory with the space-time signature (-,+,+,+,-).
The direction transverse to the brane is the second time-like direction. The
solitonic brane is $\delta$-function like, and has the property that gravity is
completely localized on the brane. That is, there are no propagating degrees of
freedom in the bulk, while on the brane we have purely 4-dimensional Einstein
gravity. In particular, there are no propagating tachyonic or negative norm
states even though the extra dimension is time-like.

</DOC>
<DOC>
<DOCNO> 101917 </DOCNO>
Quantization of singular systems with second order Lagrangians


  The path integral formulation of singular systems with second order
Lagrangian is studied by using the canonical path integral method. The path
integral of Podolsky electrodynamics is studied.

</DOC>
<DOC>
<DOCNO> 84319 </DOCNO>
Tidal Disruption of a Solar Type Star by a Super-Massive Black Hole


  We study the long term evolution of a solar type star that is being disrupted
by a super massive (10^6 solar mass) black hole. The evolution is followed from
the disruption event, which turns the star into a long thin stream of gas, to
the point where some of this gas returns to pericenter and begins its second
orbit around the black hole. Following the evolution for this long allows us to
determine the amount of mass that is accreted by the black hole. We find that
approximately 75% of the returning mass is not accreted but instead becomes
unbound, following the large compression characterizing the return to
pericenter. The impact of a tidal disruption on the surrounding gas may
therefore be like that of two consecutive supernove-type events.

</DOC>
<DOC>
<DOCNO> 119706 </DOCNO>
X-ray emission from Lindroos binary systems


  We present a study of the X-ray emission from binary systems extracted from
the Lindroos catalogue (Lindroos 1986) based on the ROSAT All-Sky survey as
well as ROSAT PSPC and HRI pointings. The studied sample consists of visual
binary systems comprised of early-type primaries and late-type secondaries. The
ages of the systems were determined by Lindroos (1985) from uvbybeta photometry
of the primaries. These ages range between 33 and 135 Myr, so if the late-type
secondaries are physically bound to the early-type primaries, they could be
Post-T Tauri stars (PTTS). We have found strong X-ray emission from several
secondaries. This fact together with their optical and IR data, make them bona
fide PTTS candidates. We have also detected X-ray emission from several
early-type primaries and, in particular, from most of the late-B type stars.
Because their HRI hardness ratios are similar to those from resolved late-type
stars, the presence of an unresolved late-type companion seems to be the cause
of this emission.

</DOC>
<DOC>
<DOCNO> 101372 </DOCNO>
Spectrum generating algebra and coherent states of the


  $C_{\lambda}$-extended oscillator algebras, generalizing the
Calogero-Vasiliev algebra, where $C_{\lambda}$ is the cyclic group of order
$\lambda$, have recently proved very useful in the context of supersymmetric
quantum mechanics and some of its variants. Here we determine the spectrum
generating algebra of the $C_{\lambda}$-extended oscillator. We then construct
its coherent states, study their nonclassical properties, and compare the
latter with those of standard $\lambda$-photon coherent states, which are
obtained as a special case. Finally, we briefly review some other types of
coherent states associated with the $C_{\lambda}$-extended oscillator.

</DOC>
<DOC>
<DOCNO> 40279 </DOCNO>
Search for Charged Higgs Bosons in e+e- Collisions at Centre-of-Mass


  A search for pair-produced charged Higgs bosons is performed with the L3
detector at LEP using data collected at centre-of-mass energies between 192 and
202 GeV, corresponding to an integrated luminosity of 233.2 pb^-1. Decays into
a charm and a strange quark or into a tau lepton and its neutrino are
considered. The observed events are consistent with the expectations from
Standard Model background processes. Including data taken at lower
centre-of-mass energies, lower limits on the charged Higgs mass are derived at
the 95% confidence level. They vary from 67.4 to 79.9GeV as a function of the
H^+/- --> tau nu branching ratio.

</DOC>
<DOC>
<DOCNO> 69551 </DOCNO>
Off-Diagonal Generalized Vector-Dominance and Colour-Dipoles in Low-x


  We briefly summarize the equivalence of off-diagonal generalized vector
dominance and the colour-dipole approach to deep-inelastic scattering (DIS) in
the diffraction region of values of $x \simeq Q^2/W^2 << 1$.

</DOC>
<DOC>
<DOCNO> 83392 </DOCNO>
Computing the Depth of a Flat


  We give algorithms for computing the regression depth of a k-flat for a set
of n points in R^d. The running time is O(n^(d-2) + n log n) when 0 < k < d-1,
faster than the best time bound for hyperplane regression or for data depth.

</DOC>
<DOC>
<DOCNO> 170066 </DOCNO>
Optimal universal two-particle entanglement processes in arbitrary


  Universal two-particle entanglement processes are analyzed in arbitrary
dimensional Hilbert spaces. On the basis of this analysis the class of possible
optimal universal entanglement processes is determined whose resulting output
states do not contain any separable states. It is shown that these processes
form a one-parameter family. For all Hilbert space dimensions larger than two
the resulting optimally entangled output states are mixtures of anti-symmetric
states which are freely entangled and which also preserve information about
input states. Within this one-parameter family there is only one process by
which all information about any input state is destroyed completely.

</DOC>
<DOC>
<DOCNO> 178797 </DOCNO>
Equal-time hierarchies for transport descriptions of fermionic fields


  A transport theory which is not restricted to the gradient and quasi-particle
approximations is presented which is formulated in terms of the energy moments,
or equivalently the equal-time derivatives of the one-particle Green functions.
A set of infinite hierarchies of kinetic and constraint equations for
equal-time quantities for the spectral and the kinetic part of the one-particle
Green function are derived. The hierarchies for the spectral function truncate
automatically as in the mean field approximation. The possibility of a
systematic truncation of the hierarchies for the kinetic part is discussed. The
effects the quantum corrections are illustrated in a simple one-dimensional
model.

</DOC>
<DOC>
<DOCNO> 69474 </DOCNO>
SU(6) breaking effects in the nucleon elastic electromagnetic form


  The effects of SU(6) breaking on the nucleon elastic form factors are
investigated within the constituent quark model formulated on the light-front.
It is shown that the kinematical SU(6) breaking caused by the Melosh rotations
of the quark spins as well as the dynamical SU(6) breaking due to the
mixed-symmetry component generated in the nucleon wave function by the
spin-dependent terms of the quark-quark interaction, can affect both GEn(Q**2)
and GMp(Q**2)/GMn(Q**2). The calculated GEn(Q**2) is found to be qualitatively
consistent with existing data. while the calculations of GM(Q**2) based on the
plus component of the current are found to be plagued by spurious effects
related to the loss of the rotational covariance in the light-front formalism.
These unwanted effects can be avoided by considering the transverse y-component
of the current. In this way our light-front predictions are found to be
consistent with the data on both GEn(Q**2) and GMp(Q**2)/GMn(Q**2). Finally, it
is shown that a suppression of the ratio GEp(Q**2)/GMp(Q**2) with respect to
the dipole-fit prediction can be expected in the constituent quark model
provided the relativistic effects generated by the Melosh rotations of the
constituent spins are taken into account.

</DOC>
<DOC>
<DOCNO> 116469 </DOCNO>
A Brief note on Fluctuations and Interactions


  In this brief note we re-emphasize the fact that an underpinning of
fluctuations characterizes the fundamental interactions in the light of El
Naschie's recent work.

</DOC>
<DOC>
<DOCNO> 12306 </DOCNO>
Elastic moduli of model random three-dimensional closed-cell cellular


  Most cellular solids are random materials, while practically all theoretical
results are for periodic models. To be able to generate theoretical results for
random models, the finite element method (FEM) was used to study the elastic
properties of solids with a closed-cell cellular structure. We have computed
the density ($\rho$) and microstructure dependence of the Young's modulus ($E$)
and Poisson's ratio (PR) for several different isotropic random models based on
Voronoi tessellations and level-cut Gaussian random fields. The effect of
partially open cells is also considered. The results, which are best described
by a power law $E\propto\rho^n$ ($1 < n <2$), show the influence of randomness
and isotropy on the properties of closed-cell cellular materials, and are found
to be in good agreement with experimental data.

</DOC>
<DOC>
<DOCNO> 151704 </DOCNO>
Conifolds with Discrete Torsion and Noncommutativity


  We study D3 branes at orbifolded conifold singularities in the presence of
discrete torsion. The vacuum moduli space of open strings becomes
non-commutative due to a deformation of the superpotential and is studied via
the representation theory of the moduli algebra. It is also shown that the
center of the moduli algebra correctly describes the underlying orbifolded
conifolds. The field theory can be obtained by a marginal deformation of the
${\cal N} = 1$ gauge theory on D3 branes at conifold singularity, the global
symmetry being broken from $SU(2) \times SU(2)$ to $U(1) \times U(1)$. By using
the AdS/CFT correspondence we argue that the marginal deformation is related to
massless KK modes of NSNS and RR two form reduced on the compact space
$T^{1,1}$. We build a $T^2$ fibration of $T^{1,1}$ and show that a D3 brane in
the bulk correspond to a D5 brane on the $T^2$ fibre. We also discuss the
possible brane construction of the system.

</DOC>
<DOC>
<DOCNO> 121701 </DOCNO>
Ages of A-type Vega-like stars from uvby$\beta$ Photometry


  We have estimated the ages of a sample of A-type Vega-like stars by using
Str\"{o}mgren \emph{uvby$\beta} photometric data and theoretical evolutionary
tracks. We find that 13 percent of these A stars have been reported as
Vega-like stars in the literature and that the ages of this subset run the
gamut from very young (50~Myr) to old (1~Gyr), with no obvious age difference
compared to those of field A stars. We clearly show that the fractional IR
luminosity decreases with the ages of Vega-like stars.

</DOC>
<DOC>
<DOCNO> 152245 </DOCNO>
Volume Preserving Diffeomorphism and Noncommutative Branes


  We give a representation of the volume preserving diffeomorphism of $\bR^p$
in terms of the noncommutative (p-2)-branes whose kinetic term is described by
the Hopf term. In the static gauge, the (p-2)-brane can be described by the
free fields and it suggests that the quantization of the algebra is possible.

</DOC>
<DOC>
<DOCNO> 178715 </DOCNO>
On the different role of protons and neutrons in antinucleon


  We compare data of antineutron and antiproton annihilation cross sections on
different targets at very low energies. After subtracting Coulomb effects, we
observe that the ratio between the antineutron proton and antiproton proton
annihilation cross sections is an oscillating function of the energy at momenta
smaller 300 MeV/c. This nontrivial behavior is confirmed by the analysis of the
relative number of antiproton-neutron and antiproton-proton annihilations in
nuclei. We show that a part of the strong shadowing phenomena in
antiproton-nucleus annihilations can be explained in terms of this oscillation,
while a part requires different explainations.

</DOC>
<DOC>
<DOCNO> 68879 </DOCNO>
The gauge invariant quark correlator in QCD sum rules and lattice QCD


  Taking the gauge invariant quark correlator as an example, in this work we
perform a direct comparison of lattice QCD simulations with the QCD sum rule
approach. The quark correlator is first investigated in the framework of QCD
sum rules and the correlation length of the quark field is calculated.
Comparing the phenomenological part of the sum rule with previous measurements
of the quark correlator on the lattice, we are able to obtain an independent
result for the correlation length. From a fit of the lattice data to the
operator product expansion, the quark condensate and the mixed quark-gluon
condensate can be extracted.

</DOC>
<DOC>
<DOCNO> 151196 </DOCNO>
Dynamics of N=2 Supersymmetric Chern-Simons Theories


  We discuss several aspects of three dimensional N=2 supersymmetric gauge
theories coupled to chiral multiplets. The generation of Chern-Simons couplings
at low-energies results in novel behaviour including compact Coulomb branches,
non-abelian gauge symmetry enhancement and interesting patterns of dynamically
generated potentials. We further show how, given any pair of mirror theories
with N=4 supersymmetry, one may flow to a pair of mirror theories with N=2
supersymmetry by gauging a suitable combination of the R-symmetries. The
resulting theories again have interesting properties due to Chern-Simons
couplings.

</DOC>
<DOC>
<DOCNO> 120364 </DOCNO>
Cosmological density perturbation on spin dominated universes and COBE


  The evolution equation of cosmic density perturbation of a spin dominated
universe in Einstein-Cartan gravity is obtained.Examples of inflationary
cosmologies with spin are also given where we compute the density perturbations
in terms of redshift and show that spin-torsion effects produce a growth on the
inhomogeneity of the universe as the redshift is high.Spin-torsion effects are
redshifted out when the Universe expands and would be rarely of importance in
present day phase of the universe.Comparison with the primordial density
fluctuation of COBE data is also obtained.From our computations a COBE type
experiment could be proposed to measure the spin-torsion effects in large scale
structure objects such as spiral Galaxies and globular clusters.

</DOC>
<DOC>
<DOCNO> 72123 </DOCNO>
Tree-level FCNC in the B system: from CP asymmetries to rare decays


  Tree-level Flavor-Changing Neutral Currents (FCNC) are characteristic of
models with extra vector-like quarks. These new couplings can strongly modify
the B^0 CP asymmetries without conflicting with low--energy constraints. In the
light of a low CP asymmetry in B --> J/\psi K_{S}, we discuss the implications
of these contributions. We find that even these low values can be easily
accommodated in these models. Furthermore, we show that the new data from B
factories tend to favor an O(20) enhancement of the b --> d l \bar{l}
transition over the SM expectation.

</DOC>
<DOC>
<DOCNO> 101594 </DOCNO>
Polynomial invariants of links satisfying cubic skein relations


  The aim of this paper is to define two link invariants satisfying cubic skein
relations. In the hierarchy of polynomial invariants determined by explicit
skein relations they are the next level of complexity after Jones, HOMFLY,
Kauffman and Kuperberg's $G_2$ quantum invariants. Our method consists in the
study of Markov traces on a suitable tower of quotients of cubic Hecke algebras
extending Jones approach.

</DOC>
<DOC>
<DOCNO> 83357 </DOCNO>
Noun-phrase co-occurrence statistics for semi-automatic semantic lexicon


  Generating semantic lexicons semi-automatically could be a great time saver,
relative to creating them by hand. In this paper, we present an algorithm for
extracting potential entries for a category from an on-line corpus, based upon
a small set of exemplars. Our algorithm finds more correct terms and fewer
incorrect ones than previous work in this area. Additionally, the entries that
are generated potentially provide broader coverage of the category than would
occur to an individual coding them by hand. Our algorithm finds many terms not
included within Wordnet (many more than previous algorithms), and could be
viewed as an ``enhancer'' of existing broad-coverage resources.

</DOC>
<DOC>
<DOCNO> 10254 </DOCNO>
Liquid Limits: The Glass Transition and Liquid-Gas Spinodal Boundaries


  The liquid-gas spinodal and the glass transition define ultimate boundaries
beyond which substances cannot exist as (stable or metastable) liquids. The
relation between these limits is analyzed {\it via} computer simulations of a
model liquid. The results obtained indicate that the liquid - gas spinodal and
the glass transition lines intersect at a finite temperature, implying a glass
- gas mechanical instability locus at low temperatures. The glass transition
lines obtained by thermodynamic and dynamic criteria agree very well with each
other.

</DOC>
<DOC>
<DOCNO> 70402 </DOCNO>
The hydrogen Lamb shift and the proton radius


  The Lamb shift measurement and theory are now both a dynamically developing
field and we give a review of the current data. Critical comparison of theory
and experiment can be done using a value of the proton charge radius and we pay
attention to several results of its determination.

</DOC>
<DOC>
<DOCNO> 120230 </DOCNO>
The jet and circumburst stellar wind of GRB 980519


  We present extensive multi-colour (UBVR_CI_C) photometry of the optical
afterglow of GRB 980519. Upon discovery, 8.3 hours after the burst, the source
was decaying as a power law, (t-t_GRB)^alpha, with a rapid decay rate alpha_1 =
- 1.73+-0.04. About 13 hours after the burst a steepening of the light-curve to
alpha_2 = -2.22+-0.04 was observed. Within the framework of current afterglow
models, we argue that the rapid initial decline, the `break' in the light
curve, and the spectral properties of the afterglow are best interpreted as
being due to a collimated ultra-relativistic jet of fixed opening angle
expanding into an inhomogeneous medium. In this scenario, we find that the
circumburst medium has a density structure that goes as r^(-2.05+-0.22). This
is characteristic of a preexisting wind expelled from a massive star. A
possible physical scenario is that the progenitor star collapsed to form a
black hole (i.e., a `collapsar'), producing the observed burst and afterglow.
However, the supernova signature expected in the light curve in such a scenario
is not detected. This either implies that the redshift of GRB980519 is greater
than 1.5 or that supernovae accompanying GRBs are not standard candles.

</DOC>
<DOC>
<DOCNO> 102736 </DOCNO>
Generalized Weierstrass Kernels on the Intersection of Two Complex


  On plane algebraic curves the so-called Weierstrass kernel plays the same
role of the Cauchy kernel on the complex plane. A straightforward prescription
to construct the Weierstrass kernel is known since one century. How can it be
extended to the case of more general curves obtained from the intersection of
hypersurfaces in a $n$ dimensional complex space? This problem is solved in
this work in the case $n=3$. As an application, the correlation functions of
bosonic string theories are constructed on a canonical curve of genus four.

</DOC>
<DOC>
<DOCNO> 84622 </DOCNO>
Cosmic microwave background anisotropies seeded by incoherent sources


  The cosmic microwave background anisotropies produced by active seeds, such
as topological defects, have been computed recently for a variety of models by
a number of authors. In this paper we show how the generic features of the
anisotropies caused by active, incoherent, seeds (that is the absence of
acoustic peaks at small scales) can be obtained semi-analytically, without
entering into the model dependent details of their formation, structure and
evolution.

</DOC>
<DOC>
<DOCNO> 70627 </DOCNO>
Bound States in NRQCD/NRQED and the Renormalization Group


  The application of renormalization group techniques to bound states in
non-relativistic QED and QCD is discussed. For QED bound states like Hydrogen
and positronium, the renormalization group allows large logarithms of the
velocity, ln v (or equivalently ln alpha's), to be predicted in a universal and
simple way. The series of (alpha ln alpha)'s are shown to terminate after a few
terms. For QCD one can systematically sum infinite series of the form [alpha_s
ln alpha_s]^k$, and answer definitively the question ``alpha_s at what
scale?''.

</DOC>
<DOC>
<DOCNO> 121586 </DOCNO>
The HI halos of spiral galaxies


  The results of observational studies on the vertical HI density distribution
and kinematics of the disks of spiral galaxies are reported and discussed.
Attention is drawn to the presence of HI emission, unknown before and here
referred to as the `beard', which has anomalous structure and kinematics,
different from the known cold HI disk. This component is extended and probably
located in the halo region, it is rotating more slowly than the disk and shows
radial inward motion. Its nature and origin -galactic fountain or infall of
primordial gas?- are still a puzzle.

</DOC>
<DOC>
<DOCNO> 71189 </DOCNO>
Phenomenology of the Standard Model from Lattice QCD


  Some recent results of lattice QCD calculations which are relevant for the
phenomenology of the Standard Model are reviewed. They concern the lattice
determinations of quark masses, studies of K-Kbar and B-Bbar mixings, and a
prediction of the B_s-mesons lifetime difference. The results of a recent
analysis of the CKM unitarity triangle, which is mostly based on the lattice
calculations of the relevant hadronic matrix elements, are also presented.

</DOC>
<DOC>
<DOCNO> 116543 </DOCNO>
The stopping of swift protons in matter and its implication for


  The velocity dependence of the stopping power of swift protons and deuterons
in low energy collisions is investigated. At low projectile energies the
stopping is mainly due to nuclear stopping and charge exchange of the electron.
The second mechanism dominates after Ep >=200 eV. A dynamical treatment of the
charge exchange mechanism based on two-center electronic wavefunctions yields
very transparent results for the exchange probability. We predict that the
stopping cross sections vary approximately as v to the 1.35 power for
projectile protons on hydrogen targets in the 1 keV energy region.

</DOC>
<DOC>
<DOCNO> 121452 </DOCNO>
Young radio-loud AGN: A new sample at low redshift


  We report on the investigation of a complete sample of young radio-loud AGN
at z<0.25, selected using the new comprehensive radio surveys and the optical
APM/POSS-I catalog. This new sample will provide a unique opportunity for
statistical studies of the early evolution of radio-loud AGN, free of
cosmological evolution effects. In particular, their local luminosity function,
linear-size and dynamical age distributions, may strongly constrain possible
evolution scenarios. In addition, this new sample is well suited for
statistical studies of other important properties, like their X-ray and
infrared emissions, optical cluster environments, and neutral hydrogen in
absorption towards the compact radio sources.

</DOC>
<DOC>
<DOCNO> 121803 </DOCNO>
On the Small-Scale Clustering of Ly-alpha Forest Clouds


  Recent measurements of the autocorrelation function of the Ly-alpha clouds
are analyzed from the point of view of a simple model with strong clustering on
the small scales. It is shown that this toy model reproduces fairly well the
important linear relation between amplitude of the absorber autocorrelation
function and neutral hydrogen column density. In addition, it predicts a
correct evolutionary trend of correlation amplitudes. Some possible
ramifications of these results are discussed.

</DOC>
<DOC>
<DOCNO> 67927 </DOCNO>
QCD forces and heavy quark bound states


  The present knowledge of QCD confining forces between static test charges is
summarised, with an emphasis on lattice results. Recent developments in
relating QCD potentials to quarkonium properties by use of effective field
theory methods are presented. The validity of non-relativistic QCD and the
adiabatic approximation with respect to heavy quark bound states is explored.
Besides the static potential and relativistic correction terms, the spectra of
glueballs and gluinoballs, hybrid excitations of the QCD flux tube between
fundamental colour sources, potentials between charges in various
representations of the SU(3) gauge group, and multi-particle interactions are
discussed. Some implications for quarkonia systems and quark-gluon hybrid
mesons are drawn.

</DOC>
<DOC>
<DOCNO> 99380 </DOCNO>
The Moyal product is the matrix product


  This is a short comment on the Moyal formula for deformation quantization. It
is shown that the Moyal algebra of functions on the plane is canonically
isomorphic to an algebra of matrices of infinite size.

</DOC>
<DOC>
<DOCNO> 84701 </DOCNO>
Quintessential Inflation with Dissipative fluid


  We have investigated cosmological models with a self-interacting scalar field
and a dissipative matter fluid as the sources of matter. Different variables
are expressed in terms of a {\it generating function}. Exact solutions are
obtained for one particular choice of the {\it generating function} The
potential corresponding to this generating function is a standard tree-level
potential arising in the perturbative regime in quantum field theory. With
suitable choice of parameters, the scale factor in our model exhibits both
inflationary behaviour in the early universe as well as an accelerating phase
at late times with a decelerating period in between. It also satisfies the
constraints for primeval nucleosynthesis and structure formation and seems to
solve the cosmic coincidence problem. The solution exhibits a attractor nature
towards a asymptotic de-sitter universe.

</DOC>
<DOC>
<DOCNO> 39816 </DOCNO>
Analysis of the experimental results from the EAS installation GAMMA at


  The phenomenological characterstics of the electron and muon components of
EAS with the size 10^5-10^7 are obtained by the GAMMA installation of the ANI
experiment at the Mt. Aragats in Armenia at the observation level 700 g/cm^2.
The experimental results are compared with other experiments and with the
simulation carried out using the CORSIKA code.

</DOC>
<DOC>
<DOCNO> 8968 </DOCNO>
Electric field induced memory and aging effects in pure solid N_2


  We report combined high sensitivity dielectric constant and heat capacity
measurements of pure solid N_2 in the presence of a small external ac electric
field in the audio frequency range. We have observed strong field induced aging
and memory effects which show that field cooled samples may be prepared in a
variety of metastable states leading to a free energy landscape with
experimentally ``tunable'' barriers, and tunneling between these states may
occur within laboratory time scales.

</DOC>
<DOC>
<DOCNO> 68071 </DOCNO>
Time-reversal violating rotation of polarization plane of light in gas


  The rotation of polarization plane of light in a gas placed in the electric
field is considered. Different mechanisms that cause this phenomenon are
investigated. Angle of polarization plane rotation for transition 6S_{1/2} ->
7S_{1/2} in cesium is estimated. The possibility to observe this effect in
experiment is discussed.

</DOC>
<DOC>
<DOCNO> 85469 </DOCNO>
A coherent approach to Spacetime Foam


  A coherent superposition of N Schwarzschild wormholes is proposed as a model
for spacetime foam. Following the subtraction procedure for manifolds with
boundaries, we calculate by variational methods the Casimir energy. A proposal
for an alternative foamy model formed by N Schwarzschild-Anti-de Sitter
wormholes is here considered. Finally, a conjecture about the foam evolution is
proposed.

</DOC>
<DOC>
<DOCNO> 121859 </DOCNO>
The thermal and non-thermal gaseous halo of NGC5775


  In this letter we present first results from spectroscopic observations of
Diffuse Ionized Gas (DIG) in the halo of NGC5775 obtained with FORS1 attached
to UT1/Antu of the Very Large Telescope (VLT). At our slit position
perpendicular to the disk (41" SE of the nucleus) the emission of [NII]6583,
[OIII]5007, and [OII]3727 is detected out to 9 kpc into the halo, allowing
possible ionization mechanisms of the DIG to be examined. Photoionization
models which assume a dilute radiation field are able to fit the data for the
disk, but they cannot account for the line ratios measured in the halo (e.g.,
[OI]/Halpha or [OII]/Halpha). In particular they fail to predict the observed
increase of [OIII]5007/Halpha with increasing z. The most striking result
concerns the kinematics of the halo gas. Velocities at high galactic latitudes
drop from the midplane value to reach the systemic velocity at z ~ 9 kpc. An
analysis of VLA archive data of the polarized radio-continuum emission at 4.86
GHz and 1.49 GHz reveals that magnetic fields in the halo have a strong
component perpendicular to the disk and are aligned with the Halpha and
radio-continuum spurs in the halo. This can result either from a strong wind
action or, more likely, from the generation of dipolar magnetic fields. We
briefly discuss the interrelation of the magnetic field structure and gas
dynamics, in particular the role of magnetic fields in gas outflows, as well as
the possible heating of DIG by magnetic reconnection.

</DOC>
<DOC>
<DOCNO> 170234 </DOCNO>
Sophisticated quantum search without entanglement


  Although entanglement is widely considered to be necessary for quantum
algorithms to improve on classical ones, Lloyd has observed recently that
Grover's quantum search algorithm can be implemented without entanglement, by
replacing multiple particles with a single particle having exponentially many
states. We explain that this maneuver removes entanglement from any quantum
algorithm. But all physical resources must be accounted for to quantify
algorithm complexity, and this scheme typically incurs exponential costs in
some other resource(s). In particular, we demonstrate that a recent
experimental realization requires exponentially increasing precision. There is,
however, a quantum algorithm which searches a `sophisticated' database (not
unlike a Web search engine) with a single query, but which we show does not
require entanglement even for multiparticle implementations.

</DOC>
<DOC>
<DOCNO> 123046 </DOCNO>
Helioseismology and solar neutrinos: an update


  We review recent advances concerning helioseismology, solar models and solar
neutrinos. Particularly we address the following points: i) helioseismic tests
of recent SSMs; ii) predictions of the Beryllium neutrino flux based on
helioseismology; iii) helioseismic tests regarding the screening of nuclear
reactions in the Sun.

</DOC>
<DOC>
<DOCNO> 10093 </DOCNO>
Two-magnon states in Cu(NO3)2*2.5D2O using inelastic neutron scattering


  We report measurements of the two-magnon states in a dimerized
antiferromagnetic chain material, copper nitrate
(\QTR{group}{Cu(NO$_{3}$)$_{2}\cdot 2.5$D$_{2}$O}). Using inelastic neutron
scattering, we have studied the one- and two-magnon excitation spectra in a
large single crystal of this material. We compare this new data with
perturbative expansions of the alternating Heisenberg chain and find good
agreement with these calculations. The data may also show evidence for the
recently proposed S=1 two-magnon bound state (Phys. Rev. B54, R9624 (1996)).

</DOC>
<DOC>
<DOCNO> 120783 </DOCNO>
Polarization Sweeps in Rotation Powered Pulsars


  We re-examine the characteristic polarization angle sweep of rotation-powered
pulsars and calculate the expected deviations from this sweep caused by
aberrational effects and by polar-cap current flow. We find that in addition to
the previously known phase shift of the entire sweep by $\Delta \Phi = -4
r/R_L$, aberration shifts the polarization angle itself by $\Delta \Psi =
-(10/3) (r/R_L) \cos \alpha$. Similarly, current flow above the polar cap
shifts the polarization sweep by $\Delta \Psi = (10/3) (r/R_L) (J/J_{GJ}) \cos
\alpha$, potentially providing a method of directly measuring the magnitude of
the current. The competition between these two effects produces a potentially
observable signature in the polarization angle sweep. Although these effects
may appear similar to orthogonal mode shifts, they are an independent
phenomenon with distinct observational characteristics.

</DOC>
<DOC>
<DOCNO> 118902 </DOCNO>
Microlensing and the Physics of Stellar Atmospheres


  The simple physics of microlensing provides a well-understood tool with which
to probe the atmospheres of distant stars in the Galaxy and Local Group with
high magnification and resolution. Recent results in measuring stellar surface
structure through broad band photometry and spectroscopy of high amplification
microlensing events are reviewed, with emphasis on the dramatic expectations
for future contributions of microlensing to the field of stellar atmospheres.

</DOC>
<DOC>
<DOCNO> 178941 </DOCNO>
Decay rates of medium-heavy Lambda-hypernuclei within the Propagator


  The Lambda decay rates in nuclei has been calculated in ref. 1 using the
Propagator Method in Local Density Approximation. We have studied the
dependence of the widths (including the one for the two-body induced process
Lambda NN -> NNN) on the N-N and Lambda-N short range correlations. Using a
reasonable parametrization of these correlations, as well as realistic nuclear
densities and Lambda wave functions, we reproduce, for the first time, the
experimental non-mesonic widths from medium to heavy hypernuclei.

</DOC>
<DOC>
<DOCNO> 10341 </DOCNO>
Dzyaloshinskii-Moriya interaction in NaV$_2$O$_5$: a microscopic study


  We present a unified account of magnetic exchange and Raman scattering in the
quasi-one-dimensional transition-metal oxide NaV$_2$O$_5$. Based on a
cluster-model approach explicit expressions for the exchange integral and the
Raman-operator are given. It is demonstrated that a combination of the
electronic-structure and the Dzyaloshinskii-Moriya interaction, allowed by
symmetry in this material, are responsible for the finite Raman cross-section
giving rise to both, one- and two-magnon scattering amplitudes.

</DOC>
<DOC>
<DOCNO> 68329 </DOCNO>
Towards String Predictions


  The aim of superstring phenomenology is to develop the tools and methodology
needed to confront string theory with experimental data. The first mandatory
task is to find string solutions which reproduce the observable data. The
subsequent goal is to extract potential signatures beyond the observable data.
Recently, by studying exact flat directions of non-Abelian singlet fields, we
demonstrated the existence of free fermionic heterotic-string models in which
the $SU(3)\times SU(2)\times U(1)_Y$-charged matter spectrum, just below the
string scale, consists solely of the MSSM spectrum. In this paper we study the
possibility that the exact flat directions leave a $U(1)_{Z^\prime}$ symmetry
unbroken at the Planck scale. We demonstrate in a specific example that such
unbroken $U(1)_{Z^\prime}$ is in general expected to be not of the GUT type but
of intrinsic stringy origin. We study its phenomenological characteristics and
the consequences in the case that $U(1)_{Z^\prime}$ remains unbroken down to
low energies. We suggest that observation in forthcoming colliders of a
$Z^\prime$, with universal couplings for the two light generations but
different couplings for the heavy generation may provide evidence for the
$Z_2\times Z_2$ orbifold which underlies the free fermionic models.

</DOC>
<DOC>
<DOCNO> 8560 </DOCNO>
Density of States of a d-wave Superconductor in the Presence of Strong


  We present a method to compute the density of states induced by N non
magnetic impurities in a d-wave superconductor, in the unitary limit of very
strong scatering centers. For frequencies very small as compared to the
superconducting gap ($\omega \ll \Delta_0$) the additional density of states
has the leading divergence ${\displaystyle \delta \rho (\omega) \simeq n_i / [
| 2 \omega | (\ln^2 |\omega/\Delta_0| + (\pi/2)^2)]}$. This result is non
perturbative.

</DOC>
<DOC>
<DOCNO> 101299 </DOCNO>
On Picard bundles over Prym varieties


  We study the birationality (onto its image) of the Abel-Prym morphism
associated with a Prym-Tuyrin variety. We use such result to prove that Picard
bundles over Prym varieties are simple and moreover they are stable when the
Abel-Prym morphism is not birational. As a consequence we obtain that Picard
bundles over moduli spaces of stable vector bundles with fixed determinant are
simple. We prove that Picard bundles over moduli spaces of rank 2 vector
bundles on curves of genus 2 bundles are stable.

</DOC>
<DOC>
<DOCNO> 14069 </DOCNO>
Dynamical quenching and annealing in self-organization multiagent models


  We study the dynamics of a generalized Minority Game (GMG) and of the Bar
Attendance Model (BAM) in which a number of agents self-organize to match an
attendance that is fixed externally as a control parameter. We compare the
usual dynamics used for the Minority Game with one for the BAM that makes a
better use of the available information. We study the asymptotic states reached
in both frameworks. We show that states that can be assimilated to either
thermodynamic equilibrium or quenched configurations can appear in both models,
but with different settings. We discuss the relevance of the parameter $G$ that
measures the value of the prize for winning in units of the fine for losing. We
also provide an annealing protocol by which the quenched configurations of the
GMG can progressively be modified to reach an asymptotic equlibrium state that
coincides with the one obtained with the BAM.

</DOC>
<DOC>
<DOCNO> 119498 </DOCNO>
Disk/corona model: The transition to ADAF


  We propose a model of the accretion flow onto a black hole consisting of the
accretion disk with an accreting two-temperature corona. The model is based on
assumptions about the radiative and conductive energy exchange between the two
phases and the pressure equilibrium. The complete model is determined by the
mass, the accretion rate, and the viscosity parameter. We present the radial
dependencies of parameters of such a two-phase flow, with advection in the
corona and the disk/corona mass exchange due to evaporation/condensation
included, and we determine the transition radius from a two-phase disk/corona
accretion to a single-phase optically thin flow (ADAF) in the innermost part of
the disk as a function of accretion rate. We identify the NLS1 galaxies with
objects accreting at a rate close to the Eddington accretion rate. The strong
variability of these objects may be related to the limit cycle behaviour
expected in this luminosity range, as the disk, unstable due to the dominance
by the radiation pressure, oscillates between the two stable branches: the
advection-dominated optically thick branch and the evaporation branch.

</DOC>
<DOC>
<DOCNO> 100027 </DOCNO>
Comments on N=4 Superconformal Algebras


  We present a new and asymmetric N=4 superconformal algebra for arbitrary
central charge, thus completing our recent work on its classical analogue with
vanishing central charge. Besides the Virasoro generator and 4 supercurrents,
the algebra consists of an internal SL(2) \otimes U(1) Kac-Moody algebra in
addition to two spin 1/2 fermions and a bosonic scalar. The algebra is shown to
be invariant under a linear twist of the generators, except for a unique value
of the continuous twist parameter. At this value, the invariance is broken and
the algebra collapses to the small N=4 superconformal algebra. In the context
of string theory, the asymmetric N=4 superconformal algebra is provided with an
explicit construction on the boundary of AdS_3, and is induced by an affine
SL(2|2) current superalgebra residing on the world sheet. Substituting the
world sheet SL(2|2) by the coset SL(2|2)/U(1) results in the small N=4
superconformal algebra on the boundary of AdS_3.

</DOC>
<DOC>
<DOCNO> 121145 </DOCNO>
Galaxy Halo Masses from Galaxy-Galaxy Lensing


  We present measurements of the extended dark halo profiles of bright early
type galaxies at redshifts 0.1 to 0.9 obtained via galaxy-galaxy lensing
analysis of images taken at the CFHT using the UH8K CCD mosaic camera. Six half
degree fields were observed for a total of 2 hours each in I and V, resulting
in catalogs containing ~20 000 galaxies per field. We used V-I color and I
magnitude to select bright early type galaxies as the lens galaxies, yielding a
sample of massive lenses with fairly well determined redshifts and absolute
magnitudes M ~ M_* \pm 1. We paired these with faint galaxies lying at angular
distances 20" to 60", corresponding to physical radii of 26 to 77 kpc (z = 0.1)
and 105 to 315 kpc (z = 0.9), and computed the mean tangential shear of the
faint galaxies. The shear falls off with radius roughly as expected for flat
rotation curve halos. The shear values were weighted in proportion to the
square root of the luminosity of the lens galaxy. Our results give a value for
the average mean rotation velocity of an L_* galaxy halo at r~50-200 kpc of v_*
= 238^{+27}_{-30} km per sec for a flat lambda (Omega_m0 = 0.3, Omega_l0 = 0.7)
cosmology (v_* = 269^{+34}_{-39} km per sec for Einstein-de Sitter), and with
little evidence for evolution with redshift. We compare to halo masses measured
by other groups/techniques. We find a mass-to-light ratio of ~121\pm28h(r/100
kpc) and these halos constitute Omega ~0.04 \pm 0.01(r/100 kpc) of closure
density. (abridged)

</DOC>
<DOC>
<DOCNO> 69143 </DOCNO>
Non-Abelian Energy Loss at Finite Opacity


  A systematic expansion in opacity, $L/\lambda$, is used to clarify the
non-linear behavior of induced gluon radiation in quark-gluon plasmas. The
inclusive differential gluon distribution is calculated up to second order in
opacity and compared to the zeroth order (factorization) limit. The opacity
expansion makes it possible to take finite kinematic constraints into account
that suppress jet quenching in nuclear collisions below RHIC
($\sqrt{s}=200$ AGeV) energies.

</DOC>
<DOC>
<DOCNO> 152479 </DOCNO>
Singularities of the Seiberg-Witten map


  We construct an explicit solution of the Seiberg-Witten map for a linear
gauge field on the non-commutative plane. We observe that this solution as well
as the solution for a constant curvature diverge when the non-commutativity
parameter theta reaches certain event horizon in the theta-space. This implies
that an ordinary Yang-Mills theory can be continuously deformed by the
Seiberg-Witten map into a non-commutative theory only within one connected
component of the theta-space.

</DOC>
<DOC>
<DOCNO> 150649 </DOCNO>
Notes on Fluctuations and Correlation Functions in Holographic


  We study the coupled equations describing fluctuations of scalars and the
metric about background solutions of N=8 gauged supergravity which are dual to
boundary field theories with renormalization group flow. For the case of a kink
solution with a single varying scalar, we develop a procedure to decouple the
equations, and we solve them in particular examples. However, difficulties
occur in the calculation of correlation functions from the fluctuations,
presumably because the AdS/CFT correspondence has not yet been properly
implemented in the coupled scalar-gravity sector. Some new examples of
correlators of operators dual to simpler uncoupled bulk scalars are given and
are satisfactory. As byproducts of our study we make some observations relevant
to the stability of domain walls in the brane-world scenario and to the
Hamilton-Jacobi formulation of holographic RG flows.

</DOC>
<DOC>
<DOCNO> 9527 </DOCNO>
Correlation functions in the factorization approach of nonextensive


  We study the long range behavior of a gas whose partition function depends on
a parameter q and it has been claimed to be a good approximation to the
partition function proposed in the formulation of nonextensive statistical
mechanics. We compare our results, at large temperatures and at the critical
point, with the case of Boltzmann-Gibbs thermodynamics for the case of a
Bose-Einstein gas. In particular, we find that for all temperatures the long
range correlations in a Bose gas decrease when the value of q departs from the
standard value q=1.

</DOC>
<DOC>
<DOCNO> 13433 </DOCNO>
Interlayer Exchange Coupling Mediated by Valence Band Electrons


  The interlayer exchange coupling mediated by valence band electrons in
all-semiconductor IV-VI magnetic/nonmagnetic superlattices is studied
theoretically. A 3D tight-binding model, accounting for the band and magnetic
structure of the constituent superlattice components is used to calculate the
spin-dependent part of the total electronic energy. The antiferromagnetic
coupling between ferromagnetic layers in EuS/PbS superlattices is obtained, in
agreement with the experimental evidences. The results obtained for the
coupling between antiferromagnetic layers in EuTe/PbTe superlattices are also
presented.

</DOC>
<DOC>
<DOCNO> 174531 </DOCNO>
Study of Residual Product Nuclide Yields from 0.1, 0.2, 0.8, and 2.6 GeV


  The direct gamma-spectrometry method is used to measure more than 350
residual product nuclide yields from 0.1, 0.2, 0.8, and 2.6 GeV proton
irradiated HgO targets. The gamma-spectrometer resolution is of 1.8 keV at the
1332 keV gamma-line. The resultant gamma-spectra are processed by the
GENIE-2000 code. The gamma-lines are identified, and the cross-sections
calculated, by the ITEP-designed SIGMA code using the PCNUDAT radioactive
database. The 27-Al(p,x)Na-22 reaction is used as monitor. The experimental
results are compared with calculations by the LAHET, CEM95, CEM2k, INUCL,
CASCADE, and YIELDX codes.

</DOC>
<DOC>
<DOCNO> 68011 </DOCNO>
Local BRST cohomology in gauge theories


  The general solution of the anomaly consistency condition (Wess-Zumino
equation) has been found recently for Yang-Mills gauge theory. The general form
of the counterterms arising in the renormalization of gauge invariant operators
(Kluberg-Stern and Zuber conjecture) and in gauge theories of the Yang-Mills
type with non power counting renormalizable couplings has also been worked out
in any number of spacetime dimensions. This Physics Report is devoted to
reviewing in a self-contained manner these results and their proofs. This
involves computing cohomology groups of the differential introduced by Becchi,
Rouet, Stora and Tyutin, with the sources of the BRST variations of the fields
("antifields") included in the problem. Applications of this computation to
other physical questions (classical deformations of the action, conservation
laws) are also considered. The general algebraic techniques developed in the
Report can be applied to other gauge theories, for which relevant references
are given.

</DOC>
<DOC>
<DOCNO> 10114 </DOCNO>
Renormalization group irreversible functions in more than two dimensions


  There are two general irreversibility theorems for the renormalization group
in more than two dimensions: the first one is of entropic nature, while the
second one, by Forte and Latorre, relies on the properties of the stress-tensor
trace, and has been recently questioned by Osborn and Shore. We start by
establishing under what assumptions this second theorem can still be valid.
Then it is compared with the entropic theorem and shown to be essentially
equivalent. However, since the irreversible function of the (corrected)
Forte-Latorre theorem is non universal (whereas the relative entropy of the
other theorem is universal), it needs the additional step of renormalization.
On the other hand, the irreversibility theorem is only guaranteed to be
unambiguous if the integral of the stress-tensor trace correlator is finite,
which happens for free theories only in dimension smaller than four.

</DOC>
<DOC>
<DOCNO> 150854 </DOCNO>
Heterotic M-Theory Cosmology in Four and Five Dimensions


  We study rolling radii solutions in the context of the four- and
five-dimensional effective actions of heterotic M-theory. For the standard
four-dimensional solutions with varying dilaton and T-modulus, we find
approximate five-dimensional counterparts. These are new, generically
non-separating solutions corresponding to a pair of five-dimensional domain
walls evolving in time. Loop corrections in the four-dimensional theory are
described by certain excitations of fields in the fifth dimension. We point out
that the two exact separable solutions previously discovered are precisely the
special cases for which the loop corrections are time-independent. Generically,
loop corrections vary with time. Moreover, for a subset of solutions they
increase in time, evolving into complicated, non-separating solutions. In this
paper we compute these solutions to leading, non-trivial order. Using the
equations for the induced brane metric, we present a general argument showing
that the accelerating backgrounds of this type cannot evolve smoothly into
decelerating backgrounds.

</DOC>
<DOC>
<DOCNO> 169612 </DOCNO>
Quantum Diagonalization of Hermitean Matrices


  To measure an observable of a quantum mechanical system leaves it in one of
its eigenstates and the result of the measurement is one of its eigenvalues.
This process is shown to be a computational resource. It allows one, in
principle, to diagonalize hermitean (N by N) matrices by quantum mechanical
measurements only. To do so, one considers the given matrix as an observable of
a single spin with appropriate length s=(N-1)/2, which can be measured using a
generalized Stern-Gerlach apparatus. Then, each run provides one eigenvalue of
the observable. As it is based on the `collapse of the wave function'
associated with a measurement, the procedure is neither a digital nor an analog
calculation---it defines thus a new quantum mechanical method of computation.

</DOC>
<DOC>
<DOCNO> 120449 </DOCNO>
Chemical evolution using SPH cosmological simulations. I:


  We develop a model to implement metal enrichment in a cosmological context
based on the hydrodynamical AP3MSPH code described by Tissera, Lambas and Abadi
(1997).The star formation model is based on the Schmidt law and has been
modified in order to describe the transformation of gas into stars in more
detail. The enrichment of the interstellar medium due to supernovae I and II
explosions is taken into account by assuming a Salpeter Initial Mass Function
and different nucleosynthesis models.The different chemical elements are mixed
within the gaseous medium according to the Smooth Particle Hydrodynamics
technique. We present tests of the code that assess the effects of resolution
and model parameters on the results. scenario and we present results of the
analysis of the star formation and chemical properties of the interstellar
medium and stellar population of the simulated galactic objects. We show that
these systems reproduce abundance ratios for primary and secondary elements of
the interstellar medium, and the correlation between the (O/H) abundance and
the gas fraction of galaxies. The numerical simulations performed provide a
detailed description of the chemical properties of galactic objects formed in
hierarchical clustering scenarios and proved to be useful tools to deepen our
understanding of galaxy formation and evolution.

</DOC>
<DOC>
<DOCNO> 40059 </DOCNO>
Phenomenology of Maximal and Near-Maximal Lepton Mixing


  We study the phenomenological consequences of maximal and near-maximal mixing
of the electron neutrino with other ($x$=tau and/or muon) neutrinos. We
describe the deviations from maximal mixing in terms of a parameter
$\epsilon\equiv1-2\sin^2\theta_{ex}$ and quantify the present experimental
status for $|\epsilon|<0.3$. We find that the global analysis of solar neutrino
data allows maximal mixing with confidence level better than 99% for $10^{-8}$
eV$^2\lsim\Delta m^2\lsim2\times10^{-7}$ eV$^2$. In the mass ranges $\Delta
m^2\gsim 1.5\times10^{-5}$ eV$^2$ and $4\times10^{-10}$ eV$^2\lsim\Delta
m^2\lsim2\times10^{-7}$ eV$^2$ the full interval $|\epsilon|<0.3$ is allowed
within 4$\sigma$(99.995 % CL). We suggest ways to measure $\epsilon$ in future
experiments. The observable that is most sensitive to $\epsilon$ is the rate
[NC]/[CC] in combination with the Day-Night asymmetry in the SNO detector. With
theoretical and statistical uncertainties, the expected accuracy after 5 years
is $\Delta \epsilon\sim 0.07$. We also discuss the effects of maximal and
near-maximal $\nu_e$-mixing in atmospheric neutrinos, supernova neutrinos, and
neutrinoless double beta decay.

</DOC>
<DOC>
<DOCNO> 70407 </DOCNO>
Neutrino Flavor Oscillations without Flavor Mixing Angles


  We demonstrate that sizable neutrino flavor oscillations can be generated in
a model with large extra spacetime dimensions even if the physics on the brane
is flavor-diagonal, the bulk neutrino theory is flavor-neutral, and the
brane/bulk couplings are flavor-blind. This is thus a compact model for
addressing neutrino flavor oscillations in higher dimensions. We also discuss
several phenomenological aspects of the ``bulk-mediated'' neutrino oscillations
inherent in this model, and show that this model contains some potentially
important new phenomenological features in the limit of large brane/bulk
coupling.

</DOC>
<DOC>
<DOCNO> 12452 </DOCNO>
Statistical Mechanics for Unstable States in Gel'fand Triplets and


  Free energies and other thermodynamical quantities are investigated in
canonical and grand canonical ensembles of statistical mechanics involving
unstable states which are described by the generalized eigenstates with complex
energy eigenvalues in the conjugate space of Gel'fand triplet. The theory is
applied to the systems containing parabolic potential barriers (PPB's). The
entropy and energy productions from PPB systems are studied. An equilibrium for
a chemical process described by reactions $A+CB\rightleftarrows AC+B$ is also
discussed.

</DOC>
<DOC>
<DOCNO> 99895 </DOCNO>
Gherardelli linkage and complete intersections


  Our main theorem characterizes the complete intersections of codimension 2 in
a projective space of dimension 3 or more over an algebraically closed field of
characteristic 0 as the subcanonical and self-linked subschemes. In order to
prove this theorem, we'll prove the Gherardelli linkage theorem, which asserts
that a partial intersection of two hypersurfaces is subcanonical if and only if
its residual intersection is, scheme-theoretically, the intersection of the two
hypersurfaces with a third.

</DOC>
<DOC>
<DOCNO> 170646 </DOCNO>
Information-Theoretic Description of No-go Theorem of a Bit Commitment


  We give a comprehensive and constructive proof of the no-go theorem of a bit
commitment given by Mayers, Lo, and Chau from the viewpoint of quantum
information theory. It is shown that there is a trade-off relation between
information acquired by Bob during the commitment phase and the ability to
change a commit bit by Alice during the opening phase. It is clarified that a
protocol that is unbiased to both Alice and Bob cannot be, at the same time,
secure against both parties. Fundamental physical constraints that govern this
no-go theorem are also discussed.

</DOC>
<DOC>
<DOCNO> 68548 </DOCNO>
Constraints on $m_s$ and $\epsilon'/\epsilon$ from Lattice QCD


  Results for light quark masses obtained from lattice QCD simulations are
compared and contrasted with other determinations. Relevance of these results
to estimates of $\epsilon'/\epsilon$ is discussed.

</DOC>
<DOC>
<DOCNO> 100742 </DOCNO>
Local calibrations for minimizers of the Mumford-Shah functional with


  Using a calibration method, we prove that, if $w$ is a function which
satisfies all Euler conditions for the Mumford-Shah functional on a
two-dimensional open set $\Omega$, and the discontinuity set of $w$ is a
segment connecting two boundary points, then for every point $(x_0, y_0)$ of
$\Omega$ there exists a neighbourhood $U$ of $(x_0, y_0)$ such that $w$ is a
minimizer of the Mumford-Shah functional on $U$ with respect to its own
boundary values on $\partial U$.

</DOC>
<DOC>
<DOCNO> 100406 </DOCNO>
Compatible and Almost Compatible Pseudo-Riemannian Metrics


  Notions of compatible and almost compatible pseudo-Riemannian metrics, which
are motivated by the theory of compatible (local and nonlocal) Poisson
structures of hydrodynamic type and generalize the notion of flat pencil of
metrics, are introduced and studied.

</DOC>
<DOC>
<DOCNO> 120679 </DOCNO>
Abundance profiles of CH3OH and H2CO toward massive young stars as


  The chemical evolution of thirteen regions of massive star formation is
studied through single-dish and interferometer line observations at
submillimeter wavelengths. The wealth of CH3OH and H2CO lines covering a large
range of excitation conditions allows us to calculate radial abundance
profiles, using the physical structures of the sources derived earlier from
submillimeter continuum and CS lines. The data indicate three types of
abundance profiles: flat profiles at CH3OH/H2 ~10^-9 for the coldest sources,
profiles with a jump in its abundance from ~10^-9 to ~10^-7 for the warmer
sources, and flat profiles at CH3OH/H2 ~few 10^-8 for the hot cores. The
location of the jump at T~100 K suggests that it is due to evaporation of grain
mantles, followed by destruction in gas-phase reactions in the hot core stage.
In contrast, the H2CO data can be well fit with a constant abundance of a few x
10^-9 throughout the envelope, providing limits on its grain surface formation.
These results indicate that T_rot(CH3OH) can be used as evolutionary indicator
during the embedded phase of massive star formation, independent of source
optical depth or orientation.

</DOC>
<DOC>
<DOCNO> 121001 </DOCNO>
Orbit Fitting and Uncertainties for Kuiper Belt Objects


  We present a procedure for determination of positions and orbital elements,
and associated uncertainties, of outer Solar System planets. The orbit-fitting
procedure is greatly streamlined compared to traditional methods because
acceleration can be treated as a perturbation to the inertial motion of the
body. These techniques are immediately applicable to Kuiper Belt Objects, for
which recovery observations are costly. Our methods produce positional
estimates and uncertainty ellipses even in the face of the substantial
degeneracies of short-arc orbit fits; the sole a priori assumption is that the
orbit should be bound or nearly so. We use these orbit-fitting techniques to
derive a strategy for determining Kuiper Belt orbits with a minimal number of
observations.

</DOC>
<DOC>
<DOCNO> 70543 </DOCNO>
Heavy quark photoproduction in the semihard QCD approach and the


  Processes of heavy quark photoproduction at HERA energies are considered
using the semihard (k_T factorization) QCD approach with emphasis of the BFKL
dynamics of gluon distributions. We investigate the dependences of the total
cross section of heavy quark photoproduction and also p_T, and rapidity
distributions on different forms of the unintegrated gluon distribution. We
present a comparision of the theoretical results with available H1 and ZEUS
experimental data for charm and beauty photoproductions.

</DOC>
<DOC>
<DOCNO> 13997 </DOCNO>
Direct current generation due to harmonic mixing: From bulk


  We discuss an effect of dc current and dc voltage (stopping bias) generation
in a semiconductor superlattice subjected by an ac electric field and its
phase-shifted n-th harmonic. In the low field limit, we find a simple
dependence of dc voltage on a strength, frequency, and relative phase of mixing
harmonics for an arbitrary even value of n.
   We show that the generated dc voltage has a maximum when a frequency of ac
field is of the order of a scattering constant of electrons in a superlattice.
This means that for typical semiconductor superlattices at room temperature
operating in the THz frequency domain the effect is really observable.
   We also made a comparison of a recent paper describing an effect of a
directed current generation in a semiconductor superlattice subjected by ac
field and its second harmonic (n=2) [K.Seeger, Appl.Phys.Lett. 76(2000)82] with
our earlier findings describing the same effect [K.Alekseev et al., Europhys.
Lett. 47(1999)595; cond-mat/9903092 ].
   For the mixing of an ac field and its n-th harmonic with n>=4, we found that
additionally to the phase-shift controlling of the dc current, there is a
frequency control. This frequency controlling of the dc current direction is
absent in the case of n=2. The found effect is that, both the dc current
suppression and the dc current reversals exist for some particular values of ac
field frequency. For typical semiconductor superlattices such an interesting
behavior of the dc current should be observable also in the THz domain.
   Finally, we briefly review the history of the problem of the dc current
generation at mixing of harmonics in semiconductors and semiconductor
microstructures.

</DOC>
<DOC>
<DOCNO> 100929 </DOCNO>
Vertex-Facet Incidences of Unbounded Polyhedra


  How much of the combinatorial structure of a pointed polyhedron is contained
in its vertex-facet incidences? Not too much, in general, as we demonstrate by
examples. However, one can tell from the incidence data whether the polyhedron
is bounded. In the case of a polyhedron that is simple and "simplicial," i.e.,
a d-dimensional polyhedron that has d facets through each vertex and d vertices
on each facet, we derive from the structure of the vertex-facet incidence
matrix that the polyhedron is necessarily bounded. In particular, this yields a
characterization of those polyhedra that have circulants as vertex-facet
incidence matrices.

</DOC>
<DOC>
<DOCNO> 121174 </DOCNO>
Gravitational Stirring in Planetary Debris Disks


  We describe gravitational stirring models of planetary debris disks using a
new multi-annulus planetesimal evolution code. The current code includes
gravitational stirring and dynamical friction; future studies will include
coagulation, fragmentation, Poynting-Robertson drag, and other physical
processes. We use the results of our calculations to investigate the physical
conditions required for small bodies in a planetesimal disk to reach the
shattering velocity and begin a collisional cascade. Our results demonstrate
that disks composed primarily of bodies with a single size will not undergo a
collisional cascade which produces small dust grains at 30-150 AU on timescales
of 1 Gyr or smaller. Disks with a size distribution of bodies reach conditions
necessary for a collisional cascade in 10 Myr to 1 Gyr if the disk is at least
as massive as a minimum mass solar nebula and if the disk contains objects with
radii of 500 km or larger. The estimated 500 Myr survival time for these disks
is close to the median age of roughly 400 Myr derived for nearby stars with
dusty disks.

</DOC>
<DOC>
<DOCNO> 84929 </DOCNO>
Theorems on gravitational time delay and related issues


  Two theorems related to gravitational time delay are proven. Both theorems
apply to spacetimes satisfying the null energy condition and the null generic
condition. The first theorem states that if the spacetime is null geodesically
complete, then given any compact set $K$, there exists another compact set $K'$
such that for any $p,q \not\in K'$, if there exists a ``fastest null
geodesic'', $\gamma$, between $p$ and $q$, then $\gamma$ cannot enter $K$. As
an application of this theorem, we show that if, in addition, the spacetime is
globally hyperbolic with a compact Cauchy surface, then any observer at
sufficiently late times cannot have a particle horizon. The second theorem
states that if a timelike conformal boundary can be attached to the spacetime
such that the spacetime with boundary satisfies strong causality as well as a
compactness condition, then any ``fastest null geodesic'' connecting two points
on the boundary must lie entirely within the boundary. It follows from this
theorem that generic perturbations of anti-de Sitter spacetime always produce a
time delay relative to anti-de Sitter spacetime itself.

</DOC>
<DOC>
<DOCNO> 10738 </DOCNO>
Slow logarithmic relaxation in models with hierarchically constrained


  A general kind of models with hierarchically constrained dynamics is shown to
exhibit logarithmic anomalous relaxation, similarly to a variety of complex
strongly interacting materials. The logarithmic behavior describes most of the
decay of the response function.

</DOC>
<DOC>
<DOCNO> 71603 </DOCNO>
A lattice calculation of the nucleon's spin-dependent structure function


  Our previous calculation of the spin-dependent structure function g_2 is
revisited. The interest in this structure function is to a great extent
motivated by the fact that it receives contributions from twist-two as well as
from twist-three operators already in leading order of 1/Q^2 thus offering the
unique possibility of directly assessing higher-twist effects. In our former
calculation the lattice operators were renormalized perturbatively and mixing
with lower-dimensional operators was ignored. However, the twist-three operator
which gives rise to the matrix element d_2 mixes non-perturbatively with an
operator of lower dimension. Taking this effect into account leads to a
considerably smaller value of d_2, which is consistent with the experimental
data.

</DOC>
<DOC>
<DOCNO> 178937 </DOCNO>
A modified connection between the mass and time in the principle of


  A simple connection between mass M of a particle or a body and time t is
proposed. The flow of time t depends on the relativechange of mass, i.e
\frac{\Delta M}{M}=- \mu dt, where \mu is unknown parameter. Some of the
simplest consequences from proposed dependence are discussed below.

</DOC>
<DOC>
<DOCNO> 100920 </DOCNO>
The submanifold geometries associated to Grassmannian systems


  There is a hierarchy of commuting soliton equations associated to each
symmetric space U/K. When U/K has rank n, the first n flows in the hierarchy
give rise to a natural first order non-linear system of partial diffferential
equations in n variables, the so called U/K-system. Let G_{m,n} denote the
Grassmannian of n-dimensional linear subspaces in R^{m+n}, and G_{m,n}^1 the
Grassmannian of space like m-dimensional linear subspaces in the Lorentzian
space R^{m+n,1}. In this paper, we use techniques from soliton theory to study
submanifolds in space forms whose Gauss-Codazzi equations are gauge equivalent
to the G_{m,n}-system or the G_{m,n}^1-system. These include submanifolds with
constant sectional curvatures, isothermic surfaces, and submanifolds admitting
principal curvature coordinates. The dressing actions of simple elements on the
space of solutions of the G_{m,n} and G_{m,n}^1 systems correspond to
B\"acklund, Darboux and Ribaucour transformations for submanifolds.

</DOC>
<DOC>
<DOCNO> 152012 </DOCNO>
Black Hole Thermodynamics, Induced Gravity and Gravity in Brane Worlds


  One of explanations of the black hole entropy implies that gravity is
entirely induced by quantum effects. By using arguments based on the AdS/CFT
correspondence we give induced gravity interpretation of the gravity in a brane
world in higher dimensional anti-de Sitter (AdS) space. The underlying quantum
theory is SU(N) theory where $N$ is related to the CFT central charge. The
theory includes massless fields which correspond to degrees of freedom of the
boundary CFT. In addition, on the brane there are massive degrees of freedom
with masses proportional to $l^{-1}$ where $l$ is the radius of AdS. At the
conformal boundary of AdS they are infinitely heavy and completely decouple. It
is the massive fields which can explain the black hole entropy. We support our
interpretation by a microscopic model of a 2D brane world in $AdS_3$.

</DOC>
<DOC>
<DOCNO> 85313 </DOCNO>
Cosmic vorticity on the brane


  We study vector perturbations about four-dimensional brane-world cosmologies
embedded in a five-dimensional vacuum bulk. Even in the absence of matter
perturbations, vector perturbations in the bulk metric can support vector
metric perturbations on the brane. We show that during de Sitter inflation on
the brane vector perturbations in the bulk obey the same wave equation for a
massless five-dimensional field as found for tensor perturbations. However, we
present the second-order effective action for vector perturbations and find no
normalisable zero-mode in the absence of matter sources. The spectrum of
normalisable states is a continuum of massive modes that remain in the vacuum
state during inflation.

</DOC>
<DOC>
<DOCNO> 69237 </DOCNO>
Mass Hierarchy from SU(1,1) Horizontal Symmetry


  The new mechanism for the generation of the chiral generations is proposed
based on the SU(1,1) horizontal gauge symmetry. The appearance of the chiral
generations is controlled by the coupling constant s of the model. This is
crucial in the grand unification scheme. The resulting chiral generations
naturally acquire the hierarchal Yukawa coupli ng matrices. Propriety of the
model to the observed hierarchical structure is discussed nume rically under
the minimal parameter set.

</DOC>
<DOC>
<DOCNO> 12461 </DOCNO>
Cluster derivation of Parisi's RSB solution for disordered systems


  We propose a general scheme in which disordered systems are allowed to
sacrifice energy equi-partitioning and separate into a hierarchy of ergodic
sub-systems (clusters) with different characteristic time-scales and
temperatures. The details of the break-up follow from the requirement of
stationarity of the entropy of the slower cluster, at every level in the
hierarchy. We apply our ideas to the Sherrington-Kirkpatrick model, and show
how the Parisi solution can be {\it derived} quantitatively from plausible
physical principles. Our approach gives new insight into the physics behind
Parisi's solution and its relations with other theories, numerical experiments,
and short range models.

</DOC>
<DOC>
<DOCNO> 13006 </DOCNO>
Introduction to stochastic error correction methods


  We propose a method for eliminating the truncation error associated with any
subspace diagonalization calculation. The new method, called stochastic error
correction, uses Monte Carlo sampling to compute the contribution of the
remaining basis vectors not included in the initial diagonalization. The method
is part of a new approach to computational quantum physics which combines both
diagonalization and Monte Carlo techniques.

</DOC>
<DOC>
<DOCNO> 13223 </DOCNO>
On the absence of spin-splitting in alpha-(BEDT-TTF)2KHg(SCN)4


  We report the results of a detailed study of the field orientation-dependence
of the de Haas-van Alphen waveform in $\alpha$-(BEDT-TTF)$_2$KHg(SCN)$_4$. By
considering the field orientation-dependence of the sign and phase of the
fundamental $\alpha$ frequency, at fields both well above and below the kink
transition field, it is found that a single value for the product of the
effective mass with the electron {\it g}-factor can explain the experimental
data deep within both the high magnetic field and low magnetic field phases.
This implies that spin-splitting does not occur within the low magnetic field
phase until the angle between the magnetic field and the normal to the
conducting planes is $\sim$~42$^\circ$. This finding contrasts greatly with
that recently published by Sasaki and Fukase, implying that electron-electron
interactions do not play a significant role in the formation of the
charge-density wave ground state. The manner in which the amplitude of the
waveform of the oscillations is damped within the low magnetic field phase is
indicative of a non harmonically indexed reduction of the amplitude, thereby
eliminating both magnetic breakdown and impurity scattering as dominant damping
mechanisms within this phase. Meanwhile, the presence of a large amplitude
second harmonic within the low magnetic field phase that has a negative sign
over a broad range of angles can only be explained by the frequency doubling
effect.

</DOC>
<DOC>
<DOCNO> 71558 </DOCNO>
Lattice Chiral Gauge Theories


  I review the substantial progress which has been made recently with the
non-perturbative construction of chiral gauge theories on the lattice. In
particular, I discuss three different approaches: a gauge invariant method
using fermions which satisfy the Ginsparg-Wilson relation, and two gauge
non-invariant methods, one using different cutoffs for the fermions and the
gauge fields, and one using gauge fixing. Open problems within all three
approaches are addressed.

</DOC>
<DOC>
<DOCNO> 84508 </DOCNO>
Perfect fluid cosmologies with varying light speed


  We have found exact constant solutions for the cosmological density parameter
using a generalization of general relativity that incorporates a cosmic
time-variation of the velocity of light in vacuum and the Newtonian gravitation
constant. We have determined the conditions when these solutions are attractors
for an expanding universe and solved the problems of the Standard Big Bang
model for perfect fluids.

</DOC>
<DOC>
<DOCNO> 10084 </DOCNO>
Ludwig: A parallel Lattice-Boltzmann code for complex fluids


  This paper describes `Ludwig', a versatile code for the simulation of
Lattice-Boltzmann (LB) models in 3-D on cubic lattices. In fact `Ludwig' is not
a single code, but a set of codes that share certain common routines, such as
I/O and communications. If `Ludwig' is used as intended, a variety of complex
fluid models with different equilibrium free energies are simple to code, so
that the user may concentrate on the physics of the problem, rather than on
parallel computing issues. Thus far, `Ludwig''s main application has been to
symmetric binary fluid mixtures. We first explain the philosophy and structure
of `Ludwig' which is argued to be a very effective way of developing large
codes for academic consortia. Next we elaborate on some parallel implementation
issues such as parallel I/O, and the use of MPI to achieve full portability and
good efficiency on both MPP and SMP systems. Finally, we describe how to
implement generic solid boundaries, and look in detail at the particular case
of a symmetric binary fluid mixture near a solid wall. We present a novel
scheme for the thermodynamically consistent simulation of wetting phenomena, in
the presence of static and moving solid boundaries, and check its performance.

</DOC>
<DOC>
<DOCNO> 122119 </DOCNO>
A modest proposal to solve the "missing mass" problem and related


  Properly interpreted data from nearby galaxies $(z\simeq 0.01)$ lead to
$\Omega \simeq 0.082$. Data from farther away galaxies $(z\simeq 1)$ with type
Ia supernovae to $\Omega =0.153$. Data to be expected from very high redshifted
galaxies $(z\simeq 10.1)$ to $\Omega =0.500$. And actual data from the CBR,
emitted at the time at which the universe became transparent $(z\simeq 1422)$
to $\Omega \simeq 0.992$. All these data are simultaneously consistent with the
standard big-bang picture (no inflation), in which $ \Omega $ is time dependent
and it is given by $\Omega (y)=1/\cosh ^{2}(y)$, being $y\equiv \sinh
^{-1}(T_{+}/T)^{1/2}$

</DOC>
<DOC>
<DOCNO> 83206 </DOCNO>
Scientific Collaboratories as Socio-Technical Interaction Networks: A


  Collaboratories refer to laboratories where scientists can work together
while they are in distant locations from each other and from key equipment.
They have captured the interest both of CSCW researchers and of science funders
who wish to optimize the use of rare scientific equipment and expertise. We
examine the kind of CSCW conceptions that help us best understand the character
of working relationships in these scientific collaboratories. Our model,
inspired by actor-network theory, considers technologies as Socio-technical
Interaction Networks (STINs). This model provides a rich understanding of the
scientific collaboratories, and also a more complete understanding of the
conditions and activities that support collaborative work in them. We
illustrate the significance of STIN models with several cases drawn from the
fields of high energy physics and materials science.

</DOC>
<DOC>
<DOCNO> 70623 </DOCNO>
CMB anisotropies from pre-big bang cosmology


  We present an alternative scenario for cosmic structure formation where
initial fluctuations are due to Kalb-Ramond axions produced during a pre-big
bang phase of inflation. We investigate whether this scenario, where the
fluctuations are induced by seeds and therefore are of isocurvature nature, can
be brought in agreement with present observations by a suitable choice of
cosmological parameters. We also discuss several observational signatures which
can distinguish axion seeds from standard inflationary models. We finally
discuss the gravitational wave background induced in this model and we show
that it may be well within the range of future observations.

</DOC>
<DOC>
<DOCNO> 11927 </DOCNO>
Scaling regimes for second layer nucleation


  Nucleation on top of two-dimensional islands with step edge barriers is
investigated using scaling arguments. The nucleation rate is expressed in terms
of three basic time scales: The time interval between deposition events, the
residence time of atoms on the island, and the encounter time required for
$i^\ast + 1$ atoms forming a stable nucleus to meet. Application to the problem
of second-layer nucleation on growing first layer islands yields a sequence of
scaling regimes with different scaling exponents relating the critical island
size, at which nucleation takes place, to the diffusion and deposition rates.
Second layer nucleation is fluctuation-dominated, in the sense that the typical
number of atoms on the island is small compared to $i^\ast + 1$, when the first
layer island density exponent $\chi$ satisfies $\chi (i^\ast + 1) < 2$. The
upper critical nucleus size, above which the conventional mean-field theory of
second layer nucleation is valid, increases with decreasing dimensionality. In
the related case of nucleation on top of multilayer mounds
fluctuation-dominated and mean-field like regimes coexist for arbitrary values
of the critical nucleus size $i^\ast$.

</DOC>
<DOC>
<DOCNO> 71932 </DOCNO>
Chargino searches at LEP for complex MSSM parameters


  We reanalyze the results of the chargino searches at LEP (on the basis of the
DELPHI 189 GeV data sample), including the possibility of complex MSSM
parameters. We point out the possible differences between the complex- and
real-parameter analysis. We check that the regions excluded by ``standard''
analyses remain generally robust against the introduction of complex
parameters, with the exception of light sneutrino and low $\tan\beta$ scenario,
where additional constraints like those given by the $Z^0$ width or electric
dipole moment measurements are necessary.

</DOC>
<DOC>
<DOCNO> 119796 </DOCNO>
Formation of a tidal dwarf galaxy in the interacting system Arp 245 (NGC


  Among the various phenomena observed in interacting galaxies is the ejection
due to tidal forces of material into the intergalactic medium and its
subsequent rearranging which can lead to the formation of self-gravitating
tidal dwarf galaxies
 (TDGs). We investigate this process with a detailed multiwavelength study of
the interacting system Arp 245 (NGC 2992/3) and a numerical model of the
collision.
 The system is observed at an early stage of the interaction, about 100 Myr
after perigalacticon, though at a time when tidal tails have already developed.
 Our HI map shows prominent counterparts to the optical tails. Whereas the
stellar and gaseous components of the plume that originates from NGC 2992
match, the stellar and HI tails emanating from NGC 2993 have a different
morphology. In particular, the HI forms a ring, a feature that has been
successfully reproduced by our numerical simulations. The HI emission in the
system as a whole peaks at the tip of the NGC 2992 tail where a gas reservoir
of about
 10^9 Msun, about 60% of the HI towards NGC 2992, coincides with a star-forming
optical condensation,
 A245N. The latter tidal object exhibits properties ranging between those of
dwarf irregular galaxies (structural parameters, gas content, star formation
rate) and those of spiral disks
 (metallicity, star formation efficiency, stellar population). Prompted by the
questions raised for this particular object, we discuss some issues related to
the definition and identification of TDGs (abridged)

</DOC>
<DOC>
<DOCNO> 150711 </DOCNO>
A Comment on Brane Bending and Ghosts in Theories with Infinite Extra


  Theories with infinite volume extra dimensions open exciting opportunities
for particle physics. We argued recently that along with attractive features
there are phenomenological difficulties in this class of models. In fact, there
is no graviton zero-mode in this case and 4D gravity is obtained by means of
continuum bulk modes. These modes have additional degrees of freedom which do
not decouple at low energies and lead to inconsistent predictions for light
bending and the precession of Mercury's perihelion. In a recent papers,
[hep-th/0003020] and [hep-th/0003045] the authors made use of brane bending in
order to cancel the unwanted physical polarization of gravitons. In this note
we point out that this mechanism does not solve the problem since it uses a
{\it ghost} which cancels the extra degrees of freedom. In order to have a
consistent model the ghost should be eliminated. As soon as this is done, 4D
gravity becomes unconventional and contradicts General Relativity. New
mechanisms are needed to cure these models. We also comment on the possible
decoupling of the ghost at large distances due to an apparent flat-5D nature of
space-time and on the link between the presence of ghosts and the violation of
positive-energy conditions.

</DOC>
<DOC>
<DOCNO> 72010 </DOCNO>
Electroweak preheating on a lattice


  In many inflationary models, a large amount of energy is transferred rapidly
to the long-wavelength matter fields during a period of preheating after
inflation. We study how this changes the dynamics of the electroweak phase
transition if inflation ends at the electroweak scale. We simulate a classical
SU(2)xU(1)+Higgs model with initial conditions in which the energy is
concentrated in the long-wavelength Higgs modes. With a suitable initial energy
density, the electroweak symmetry is restored non-thermally but broken again
when the fields thermalize. During this symmetry restoration, baryon number is
violated, and we measure its time evolution, pointing out that it is highly
non-Brownian. This makes it difficult to estimate the generated baryon
asymmetry.

</DOC>
<DOC>
<DOCNO> 120893 </DOCNO>
Bi-metric Gravity and "Dark Matter"


  We present a bi-metric theory of gravity containing a length scale of
galactic size. For distances less than this scale the theory satisfies the
standard tests of General Relativity. For distances greater than this scale the
theory yields an effective gravitational constant much larger than the locally
observed value of Newton's constant. The transition from one regime to the
other through the galactic scale can explain the observed rotation curves of
galaxies and hence the effects normally attributed to the presence of dark
matter. Phenomena on an extragalactic scale such as galactic clusters and the
expansion of the universe are controlled by the enhanced gravitational
coupling. This provides an explanation of the missing matter normally invoked
to account for the observed value of Hubble's constant in relation to observed
matter.

</DOC>
<DOC>
<DOCNO> 67866 </DOCNO>
Constraining Penguin Contributions and the CKM Angle $\gamma$ through


  The decays $B_d\to\pi^+\pi^-$ and $B_s\to K^+K^-$ provide an interesting
strategy to extract the CKM angle $\gamma$ at ``second-generation'' $B$-physics
experiments of the LHC era. A variant for ``first-generation'' experiments can
be obtained, if $B_s\to K^+K^-$ is replaced by $B_d\to\pi^\mp K^\pm$. We show
that the most recent experimental results for the CP-averaged
$B_d\to\pi^+\pi^-$ and $B_d\to\pi^\mp K^\pm$ branching ratios imply a rather
restricted range for the corresponding penguin parameters, and upper bounds on
the direct CP asymmetries $A_{CP}^{dir}(B_d\to\pi^+\pi^-)$ and
$A_{CP}^{dir}(B_d\to\pi^\mp K^\pm)$. Moreover, we point out that interesting
constraints on $\gamma$ can be obtained from the CP-averaged $B_d\to\pi^+\pi^-$
and $B_d\to\pi^\mp K^\pm$ branching ratios, if in addition mixing-induced CP
violation in the former decay is measured, and the $B^0_d$--$\bar{B^0_d}$
mixing phase is fixed through $B_d\to J/\psi K_S$. An extraction of $\gamma$
becomes possible, if furthermore direct CP violation in $B_d\to\pi^+\pi^-$ or
$B_d\to\pi^\mp K^\pm$ is observed.

</DOC>
<DOC>
<DOCNO> 169916 </DOCNO>
Does Anti-Parallel Spin Always Contain more Information ?


  We show that the Bloch vectors lying on any great circle is the largest set
S(L) for which the parallel states |n,n> can always be transformed into the
anti-parallel states |n,-n>. Thus more information about the Bloch vector is
not extractable from |n,-n> than from |n,n> by any measuring strategy, for the
Bloch vector belonging to S(L). Surprisingly, the largest set of Bloch vectors
for which the corresponding qubits can be flipped is again S(L). We then show
that probabilistic exact parallel to anti-parallel transformation is not
possible if the corresponding anti-parallel spins span the whole Hilbert space
of the two qubits. These considerations allow us to generalise a conjecture of
Gisin and Popescu (Phys. Rev. Lett. 83 432 (1999)).

</DOC>
<DOC>
<DOCNO> 70729 </DOCNO>
Quarkonium Production through Hard Comover Rescattering in Polarized and


  In this paper hadroproduction of charmonium states in polarized pp collisions
is discussed. A thermal picture for the gluonic cloud of comovers is given
making contact between the formalism and the measured unpolarized cross
sections. The experimentally observed non-polarization of the final J/psi
states leads to the consequence that no correlations between the initial proton
spin and the final charmonium spin should be existent. Hence the single spin
asymmetries vanish to leading order in that model.

</DOC>
<DOC>
<DOCNO> 85177 </DOCNO>
Matching Spherical Dust Solutions to Construct Cosmological Models


  Conditions for smooth cosmological models are set out and applied to
inhomogeneous spherically symmetric models constructed by matching together
different Lemaitre-Tolman-Bondi solutions to the
 Einstein field equations. As an illustration the methods are applied to a
collapsing dust sphere in a curved background. This describes a region which
expands and then collapses to form a black hole in an
 Einstein de Sitter background. We show that in all such models if there is no
vacuum region then the singularity must go on accreting matter for an infinite
LTB time.

</DOC>
<DOC>
<DOCNO> 121753 </DOCNO>
Unlocking the Keyhole - H2 and PAH emission from molecular clumps in the


  To better understand the environment surrounding CO emission clumps in the
Keyhole Nebula, we have made images of the region in H2 1-0 S(1) (2.122 um)
emission and polycyclic aromatic hydrocarbon (PAH) emission at 3.29 um. Our
results show that the H2 and PAH emission regions are morphologically similar,
existing as several clumps, all of which correspond to CO emission clumps and
dark optical features. The emission confirms the existence of photodissociation
regions (PDRs) on the surface of the clumps. By comparing the velocity range of
the CO emission with the optical appearance of the H2 and PAH emission, we
present a model of the Keyhole Nebula in which the most negative velocity
clumps are in front of the ionization region, the clumps at intermediate
velocities are in it, and those which have the least negative velocities are at
the far side. It may be that these clumps, which appear to have been swept up
from molecular gas by the stellar winds from eta Car, are now being over-run by
the ionization region and forming PDRs on their surfaces. These clumps comprise
the last remnants of the ambient molecular cloud around eta Car.

</DOC>
<DOC>
<DOCNO> 118201 </DOCNO>
The Magellanic Clouds and the Primordial Helium Abundance


  A new determination of the pregalactic helium abundance based on the
Magellanic Clouds H II regions is discussed. This determination amounts to Yp =
0.2345 +- 0.0030 and is compared with those derived from giant extragalactic H
II regions in systems with extremely low heavy elements content. It is
suggested that the higher primordial value derived by other authors from giant
H II region complexes could be due to two systematic effects: the presence of
neutral hydrogen inside the helium Stromgren sphere and the presence of
temperature variations inside the observed volume.

</DOC>
<DOC>
<DOCNO> 122005 </DOCNO>
Separating Thermal and Nonthermal X-Rays in Supernova Remnants I: Total


  The remnant of SN 1006 has an X-ray spectrum dominated by nonthermal
emission, and pre-ASCA observations were well described by a synchrotron
calculation with electron energies limited by escape. We describe the results
of a much more stringent test: fitting spatially integrated ASCA GIS (0.6-8
keV) and RXTE PCA (3-10 keV) data with a combination of the synchrotron model
SRESC newly ported to XSPEC and a new thermal shock model VPSHOCK. The new
model can describe the continuum emission above 2 keV well, in both spatial
distribution and spectrum. We find that the emission is dominantly nonthermal,
with a small but noticeable thermal component: Mg and Si are clearly visible in
the integrated spectrum. The synchrotron component rolls off smoothly from the
extrapolated radio spectrum, with a characteristic rolloff frequency of 3.1E17
Hz, at which the spectrum has dropped about a factor of 6 below a powerlaw
extrapolation from the radio spectrum. Comparison of TeV observations with new
TeV model images and spectra based on the X-ray model fits gives a mean
post-shock magnetic field strength of about 9 microGauss, implying (for a
compression ratio of 4) an upstream magnetic field of 3 microGauss, and fixing
the current energy content in relativistic electrons at about 7E48 ergs,
resulting in a current electron-acceleration efficiency of about 5%. This total
energy is about 100 times the energy in the magnetic field. Our results
indicate that joint thermal and nonthermal fitting, using sophisticated models,
will be required for analysis of most supernova-remnant X-ray data in the
future.

</DOC>
<DOC>
<DOCNO> 120646 </DOCNO>
Dissipative N - body code for galaxy evolution


  The evolving galaxy is considered as a system of baryonic fragments embedded
into the static dark nonbaryonic (DH) and baryonic (BH) halo and subjected to
gravitational and viscous interactions. Although the chemical evolution of each
separate fragment is treated in the frame of one -- zone close box model with
instantaneous recycling, its star formation (SF) activity is a function of mean
local gas density and, therefore, is strongly influenced by other interacting
fragments. In spite of its simplicity this model provides a realistic
description of the process of galaxy formation and evolution over the Hubble
timescale.

</DOC>
<DOC>
<DOCNO> 150564 </DOCNO>
Off-Shell Formulation of Simple Supersymmetric Yang-Mills


  An off-shell formulation for 6 and 10 dimensions simple supersymmetric
Yang-Mills theories is presented. While the fermionic fields couple to left
action of S^3 and S^7 respectively, the auxiliary ones couple to right action
(and vice versa). To close the algebra off-shell, left and right actions must
commute. For 6 dimensions quaternions work fine. The 10 dimensional case needs
special care. Pure spinors and soft Lie algebra (algebra with structure
functions instead of structure constants) are essential. Some tools useful for
constructing the superspace are also derived. We show how to relate our results
to the early works of Evans and Berkovits.

</DOC>
<DOC>
<DOCNO> 13037 </DOCNO>
Twist Mode in Spherical Alkali Metal Clusters


  A remarkable orbital quadrupole magnetic resonance, so-called twist mode, is
predicted in alkali metal clusters where it is represented by $I^{\pi}=2^-$
low-energy excitations of valence electrons with strong M2 transitions to the
ground state. We treat the twist by both macroscopic and microscopic ways. In
the latter case, the shell structure of clusters is fully exploited, which is
crucial for the considered size region ($8\le N_e\le 1314$). The
energy-weighted sum rule is derived for the pseudo-Hamiltonian. In medium and
heavy spherical clusters the twist dominates over its spin-dipole counterpart
and becomes the most strong multipole magnetic mode.

</DOC>
<DOC>
<DOCNO> 123262 </DOCNO>
Accretion Disk Torqued by a Black Hole


  If a Kerr black hole is connected to a disk rotating around it by a magnetic
field, the rotational energy of the Kerr black hole provides an energy source
for the radiation of the disk in addition to disk accretion. The black hole
exerts a torque on the disk, which transfers energy and angular momentum
between the black hole and the disk. If the black hole rotates faster than the
disk, energy and angular momentum are extracted from the black hole and
transfered to the disk. The energy deposited into the disk is eventually
radiated away by the disk, which will increase the efficiency of the disk. If
the black hole rotates slower than the disk, energy and angular momentum are
transfered from the disk to the black hole, which will lower the efficiency of
the disk. With suitable boundary conditions, quasi-steady state solutions are
obtained for a thin Keplerian disk magnetically coupled to a Kerr black hole.
By ``quasi-steady state'' we mean that any macroscopic quantity at a given
radius in the disk slowly changes with time: the integrated change within one
rotation period of the disk is much smaller than the quantity itself. We find
that, the torque produced by the magnetic coupling propagates only outward in
the disk, the total radiation flux of the disk is a superposition of the
radiation flux produced by the magnetic coupling and that produced by
accretion. Most interestingly, a disk magnetically coupled to a rapidly
rotating black hole can radiate without accretion. Such a disk has an infinite
efficiency. For a specific example that the magnetic field touches the disk at
the inner boundary, the radial radiation profile is very different from that of
a standard accretion disk: the emissivity index is significantly bigger, most
radiation comes from a region which is closer to the center of the disk.

</DOC>
<DOC>
<DOCNO> 11766 </DOCNO>
Terahertz radiation from magnetoresistive


  Terahertz (THz) radiation with its spectrum extending up to 1 THz has been
observed by an illumination of femtosecond optical pulses to optical switching
devices fabricated on magnetoresistive manganite thin films;
Pr$_{0.7}$Ca$_{0.3}$MnO$_3$. The THz radiation strongly depends on temperature
$T$ and its $T$ trend reverses sign across charge-orbital and spin ordering
$T$'s.

</DOC>
<DOC>
<DOCNO> 83428 </DOCNO>
Sequence-Based Abstract Interpretation of Prolog


  Many abstract interpretation frameworks and analyses for Prolog have been
proposed, which seek to extract information useful for program optimization.
Although motivated by practical considerations, notably making Prolog
competitive with imperative languages, such frameworks fail to capture some of
the control structures of existing implementations of the language.
  In this paper we propose a novel framework for the abstract interpretation of
Prolog which handles the depth-first search rule and the cut operator. It
relies on the notion of substitution sequence to model the result of the
execution of a goal. The framework consists of (i) a denotational concrete
semantics, (ii) a safe abstraction of the concrete semantics defined in terms
of a class of post-fixpoints, and (iii) a generic abstract interpretation
algorithm. We show that traditional abstract domains of substitutions may
easily be adapted to the new framework, and provide experimental evidence of
the effectiveness of our approach. We also show that previous work on
determinacy analysis, that was not expressible by existing abstract
interpretation frameworks, can be seen as an instance of our framework.

</DOC>
<DOC>
<DOCNO> 121703 </DOCNO>
Phases of QCD at High Baryon Density


  We review recent work on the phase structure of QCD at very high baryon
density. We introduce the phenomenon of color superconductivity and discuss how
the quark masses and chemical potentials determine the structure of the
superfluid quark phase. We comment on the possibility of kaon condensation at
very high baryon density and study the competition between superfluid, density
wave, and chiral crystal phases at intermediate density.

</DOC>
<DOC>
<DOCNO> 122912 </DOCNO>
X-ray variability in a complete sample of Soft X-ray selected AGN


  We present ROSAT All-Sky Survey and ROSAT pointed observations (PSPC and HRI)
of a complete sample of 113 bright soft X-ray AGN selected from the ROSAT
Bright Source Catalog. We compare these observations in order to search for
extreme cases of flux and spectral X-ray variability - X-ray transient AGN.
Three definite transients and one transient candidate are found.
 The other sources show amplitude variations typically by factors of 2-3 on
timescales of years. We found that the variability strength on timescales of
days is a function of the steepness of the X-ray spectrum: steeper X-ray
objects show stronger variability than flat X-ray spectrum sources. We also
present new HRI measurements of our extreme X-ray transients IC 3599 and
WPVS007. We discuss possible models to explain the X-ray transience and the
variabilities observed in the non-transient sources.

</DOC>
<DOC>
<DOCNO> 100120 </DOCNO>
On the expected value of the minimum assignment


  The minimum k-assignment of an m by n matrix X is the minimum sum of k
entries of X, no two of which belong to the same row or column. If X is
generated by choosing each entry independently from the exponential
distribution with mean 1, then Coppersmith and Sorkin conjectured that the
expected value of its minimum k-assignment is \sum_{i,j \ge 0, i+j<k}
1/((m-i)(n-j)) and they (with Alm) have proven this for k < 5 and in certain
cases when k=5 or k=6. They were motivated by the special case of k=m=n, where
the expected value was conjectured by Parisi to be \sum_{i=1}^k 1/(i^2).
  In this paper we describe our efforts to prove the Coppersmith-Sorkin
conjecture. We give evidence for the following stronger conjecture, which
generalizes theirs.
  Conjecture. Suppose that r_1,...,r_m and c_1,...,c_n are positive real
numbers. Let X be a random m by n matrix in which entry x_{ij} is chosen
independently from the exponential distribution with mean 1/(r_ic_j). Then the
expected value of the minimum k-assignment of X is \sum_{I,J} (-1)^{k - 1 - |I|
- |J|} \binom{m + n - 1 - |I| - |J|}{k - 1 - |I| - |J|}\frac{1}{(\sum_{i \notin
I}r_i) (\sum_{j \notin J} c_j)}.
  Here the sum is over proper subsets I of {1,...,m} and J of {1,...,n} whose
cardinalities |I| and |J| satisfy |I|+|J|<k.

</DOC>
<DOC>
<DOCNO> 118140 </DOCNO>
The Light Elements Be and B as Stellar Chronometers in the Early Galaxy


  Recent detailed simulations of Galactic Chemical Evolution have shown that
the heavy elements, in particular [Fe/H], are expected to exhibit a weak, or
absent, correlation with stellar ages in the early Galaxy due to the lack of
efficient mixing of interstellar material enriched by individual Type II
supernovae. A promising alternative "chronometer" of stellar ages is suggested,
based on the expectation that the light elements Be and B are formed primarily
as spallation products of Galactic Cosmic Rays.

</DOC>
<DOC>
<DOCNO> 68450 </DOCNO>
Hadronic matrix elements from the lattice


  Lattice matrix elements are briefly reviewed. In the quenched approximation
$f_B$, $B_B$ and $B_K$ are now under good control. Experimental hints for
$f^{\rm expt}_{D_S}> f^{\rm QQCD}_{D_S}$ are noted; precise determination of
$f_{D_S}$ from experiment as well as from the lattice is strongly advocated.
Lattice calculations of the form factor for $B\to\pi\ell\nu$ at relatively
large value of $q^2$ have made good progress and should be useful in
conjunction with precise measurement of the differential spectra expected from
$B$-factories. Recent attempt at $K\to \pi\pi$ using staggered quarks is
briefly discussed; use of non-perturbative renormalization, improved actions
and operators with staggered quarks is emphasized. Due to the good chiral
behavior of domain wall quarks it would be useful to study $K\to \pi\pi$ with
this discretization.

</DOC>
<DOC>
<DOCNO> 150762 </DOCNO>
New local symmetry for QED in two dimensions


  A new local, covariant and nilpotent symmetry is shown to exist for the
interacting BRST invariant U(1) gauge theory in two dimensions of space-time.
Under this new symmetry, it is the gauge-fixing term that remains invariant and
the corresponding transformations on the Dirac fields turn out to be the
analogue of chiral transformations. The extended BRST algebra is derived for
the generators of all the underlying symmetries, present in the theory. This
algebra turns out to be the analogue of the algebra obeyed by the de Rham
cohomology operators of differential geometry. Possible interpretations and
implications of this symmetry are pointed out in the context of BRST cohomology
and Hodge decomposition theorem.

</DOC>
<DOC>
<DOCNO> 121050 </DOCNO>
Discovery of a Close Pair of z = 4.25 Quasars from the Sloan Digital Sky


  We report the discovery of a pair of z = 4.25 quasars with a separation of 33
arcseconds. The brighter of the two objects was identified as a high-redshift
quasar candidate from Sloan Digital Sky Survey multicolor imaging data, and the
redshift was measured from a spectrum obtained with the Hobby-Eberly Telescope.
The slit orientation of this observation {\it by chance} included another
quasar, approximately one magnitude fainter and having the same redshift as the
target. This is the third serendipitous discovery of a z > 4 quasar. The
differences in the relative strengths and profiles of the emission lines
suggest that this is a quasar pair and not a gravitational lens. The two
objects are likely to be physically associated; the projected physical
separation is approximately 210 $h_{50}^{-1}$ kpc and the redshifts are
identical to $\approx$ 0.01, implying a radial physical separation of 950
$h_{50}^{-1}$ kpc or less. The existence of this pair is strong circumstantial
evidence that $z \sim 4$ quasars are clustered.

</DOC>
<DOC>
<DOCNO> 152628 </DOCNO>
Calabi-Yau Manifolds Over Finite Fields, I


  We study Calabi-Yau manifolds defined over finite fields. These manifolds
have parameters, which now also take values in the field and we compute the
number of rational points of the manifold as a function of the parameters. The
intriguing result is that it is possible to give explicit expressions for the
number of rational points in terms of the periods of the holomorphic
three-form. We show also, for a one parameter family of quintic threefolds,
that the number of rational points of the manifold is closely related to as the
number of rational points of the mirror manifold. Our interest is primarily
with Calabi-Yau threefolds however we consider also the interesting case of
elliptic curves and even the case of a quadric in CP_1 which is a zero
dimensional Calabi-Yau manifold. This zero dimensional manifold has trivial
dependence on the parameter over C but a not trivial arithmetic structure.

</DOC>
<DOC>
<DOCNO> 101686 </DOCNO>
Flops and derived categories


  This paper contains some applications of Fourier-Mukai techniques to the
birational geometry of threefolds. In particular, we prove that birational
Calabi-Yau threefolds have equivalent derived categories. To do this we show
how flops arise naturally as moduli spaces of perverse coherent sheaves.

</DOC>
<DOC>
<DOCNO> 40540 </DOCNO>
The diffractive structure function at the Tevatron: CDF results


  Results on hard diffraction from CDF are reviewed with emphasis on the
determination of the diffractive structure function of the (anti)proton from
single diffractive and double Pomeron exchange dijet production. Comparison of
the diffractive dijet results with predictions based on diffractive deep
inelastic scattering at HERA shows a breakdown of conventional QCD
factorization. A similar breakdown is observed within the CDF results in
comparing the structure functions obtained from single diffraction and double
Pomeron exchange.

</DOC>
<DOC>
<DOCNO> 85603 </DOCNO>
Classification of image distortions in terms of Petrov types


  An observer surrounded by sufficiently small spherical light sources at a
fixed distance will see a pattern of elliptical images distributed over the
sky, owing to the distortion effect (shearing effect) of the spacetime geometry
upon light bundles. In lowest non-trivial order with respect to the distance,
this pattern is completely determined by the conformal curvature tensor (Weyl
tensor) at the observation event. In this paper we derive formulas that allow
to calculate these distortion patterns in terms of the Newman-Penrose
formalism. Then we represent the distortion patterns graphically for all Petrov
types, and we discuss their dependence on the velocity of the observer.

</DOC>
<DOC>
<DOCNO> 85064 </DOCNO>
Energy Localization Invariance of Tidal Work in General Relativity


  It is well known that, when an external general relativistic (electric-type)
tidal field E(t) interacts with the evolving quadrupole moment I(t) of an
isolated body, the tidal field does work on the body (``tidal work'') -- i.e.,
it transfers energy to the body -- at a rate given by the same formula as in
Newtonian theory: dW/dt = -1/2 E dI/dt. Thorne has posed the following
question: In view of the fact that the gravitational interaction energy between
the tidal field and the body is ambiguous by an amount of order E(t)I(t), is
the tidal work also ambiguous by this amount, and therefore is the formula
dW/dt = -1/2 E dI/dt only valid unambiguously when integrated over timescales
long compared to that for I(t) to change substantially? This paper completes a
demonstration that the answer is no; dW/dt is not ambiguous in this way. More
specifically, this paper shows that dW/dt is unambiguously given by -1/2 E
dI/dt independently of one's choice of how to localize gravitational energy in
general relativity. This is proved by explicitly computing dW/dt using various
gravitational stress-energy pseudotensors (Einstein, Landau-Lifshitz, Moller)
as well as Bergmann's conserved quantities which generalize many of the
pseudotensors to include an arbitrary function of position. A discussion is
also given of the problem of formulating conservation laws in general
relativity and the role played by the various pseudotensors.

</DOC>
<DOC>
<DOCNO> 101134 </DOCNO>
Enveloping actions and Takai duality for partial actions


  We show that any continuous partial action on a topological space has a
unique enveloping action, i.e. it is the restriction of a global action. In the
case of C^*-algebras we prove that any partial action has an enveloping action
up to Morita equivalence. The study of enveloping actions up to Morita
equivalence reveals the form that Takai duality takes for partial actions.

</DOC>
<DOC>
<DOCNO> 9793 </DOCNO>
Dynamically Induced Multi-Channel Kondo Effect


  We study how the multi-channel Kondo effect is dynamically induced to affect
the photoemission and the inverse photoemission spectrum when an electron is
emitted from (or added to) the completely screened Kondo impurity with spin
$S>1/2$. The spectrum thereby shows a power-law edge singularity characteristic
of the multi-channel Kondo model. We discuss this anomalous behavior by using
the exact solution of the multi-channel Kondo model and boundary conformal
field theory. The idea is further applied to the photoemission for quantum spin
systems, in which the edge singularity is controlled by the dynamically induced
overscreening effect with a mobile Kondo impurity.

</DOC>
<DOC>
<DOCNO> 40360 </DOCNO>
Charm and bottom production in two-photon collisions with OPAL


  A preliminary update of the previous OPAL measurement of the inclusive
production of D* mesons in anti-tagged photon-photon collisions is presented
together with the first preliminary OPAL measurement of bottom production in
photon-photon collisions.

</DOC>
<DOC>
<DOCNO> 102255 </DOCNO>
N-fold Supersymmetry for a Periodic Potential


  We report a new type of supersymmetry, "N-fold supersymmetry", in
one-dimensional quantum mechanics. Its supercharges are N-th order polynomials
of momentum: It reduces to ordinary supersymmetry for N=1, but for other values
of N the anticommutator of the supercharges is not the ordinary Hamiltonian,
but is a polynomial of the Hamiltonian. (For this reason, the original
Hamiltonian is referred to as the "Mother Hamiltonian".) This supersymmetry
shares some features with the ordinary variety, the most notable of which is
the non-renormalization theorem. An N-fold supersymmetry was earlier found for
a quartic potential whose supersymmetry is spontaneously broken. Here we report
that it also holds for a periodic potential, albeit with somewhat different
supercharges, whose supersymmetry is not broken.

</DOC>
<DOC>
<DOCNO> 70001 </DOCNO>
Microscopic Theory of the Standard Model


  The operator manifold formalism (part I) enables the unification of the
geometry and the field theory, and yields the quantization of geometry. This is
the mathematical framework for our physical outlook that the geometry and
fields, with the internal symmetries and all interactions, as well the four
major principles of relativity (special and general), quantum, gauge and colour
confinement, are derivative, and come into being simultaneously in the stable
system of the underlying ``primordial structures''. In part II we attempt to
develop, further, the microscopic approach to the Standard Model of particle
physics, which enables an insight to the key problems of particle
phenomenology. We suggest the microscopic theory of the unified electroweak
interactions. The Higgs bosons have arisen on an analogy of the Cooper pairs in
superconductivity. Besides of microscopic interpretation of all physical
parameters the resulting theory also makes plausible following testable
implications for the current experiments: 1. The Higgs bosons never could
emerge in spacetime continuum, thus, they cannot be discovered in these
experiments nor at any energy range. 2. For each of the three SM families of
quarks and leptons there are corresponding heavy family partners with the same
quantum numbers lying far above the electroweak scale, respectively, at the
energy threshold values: $E_{1}>(419.6 \pm 12.0)GeV, \quad E_{2}= (457.6 \pm
13.2)GeV$ and $E_{3}=(521.4 \pm 15.0)GeV.$

</DOC>
<DOC>
<DOCNO> 40558 </DOCNO>
Search for Rare and Forbidden Charm Meson Decays D0--> V l+ l- and h h l


  We report the results of a search for flavor-changing neutral current,
lepton-flavor, and lepton-number violating decays of the 3 and 4-body decay
modes of D0 (and its antiparticle) containing muons and electrons. Using data
from Fermilab charm hadroproduction experiment E791, we examine modes with two
leptons and either a Rho(0), Kstar, or Phi vector meson or a non-resonant Pi
Pi, K Pi, or K K pair of pseudoscalar mesons. No evidence for any of these
decays is found. Therefore, we present branching-fraction upper limits at 90%
confidence level for the 27 decay modes examined (18 new).

</DOC>
<DOC>
<DOCNO> 11483 </DOCNO>
The Orbit Space Approach to the Theory of Phase Transitions: The


  We consider the problem of the determination of the isotropy classes of the
orbit spaces of all the real linear groups, with three independent basic
invariants satisfying only one independent relation. The results are obtained
in the $\hat P$-matrix approach solving a universal differential equation ({\em
master equation}) which involves as free parameters only the degrees $d_a$ of
the invariants. We begin with some remarks which show how the $\hat{P}$-matrix
approach may be relevant in physical contexts where the study of invariant
functions is important, like in the analysis of phase spaces and structural
phase transitions (Landau's theory).

</DOC>
<DOC>
<DOCNO> 118833 </DOCNO>
Complete Zeldovich approximation


  We have developed a generalization of the Zeldovich approximation (ZA) that
is exact in a wide variety of situations, including plannar, spherical and
cilyndrical symmetries. We have shown that this generalization, that we call
complete Zeldovich approximation (CZA), is exact to second order at an
arbitrary point within any field. For gaussian fields, the third order error
have been obtained and shown to be very small. For statistical purposes, the
CZA leads to results exact to the third order.

</DOC>
<DOC>
<DOCNO> 169987 </DOCNO>
Generalized Jaynes-Cummings Model with Intensity-Dependent and


  We study the intensity-dependent and nonresonant Jaynes-Cummings Hamiltonian
when the field is described by an arbitrary shape-invariant system. We
determine the eigenstates, eigenvalues, time evolution matrix and the
population inversion matrix factor.

</DOC>
<DOC>
<DOCNO> 118628 </DOCNO>
The European Large Area ISO Survey I: Goals, Definition and Observation


  We describe the European Large Area ISO Survey (ELAIS). ELAIS was the largest
single Open Time project conducted by ISO, mapping an area of 12 square degrees
at 15mu with ISO-CAM and at 90mu with ISO-PHOT. Secondary surveys in other ISO
bands were undertaken by the ELAIS team within the fields of the primary
survey, with 6 square degrees being covered at 6.7mu and 1 square degree at
175mu. This paper discusses the goals of the project and the techniques
employed in its construction, as well as presenting details of the observations
carried out, the data from which are now in the public domain. We outline the
ELAIS ``Preliminary Analysis'' which led to the detection of over 1000 sources
from the 15 and 90 mu surveys (the majority selected at 15mu with a flux limit
of ~3 mJy), to be fed into a ground-based follow-up campaign, as well as a
programme of photometric observations of detected sources using both ISO-CAM
and ISO-PHOT. We detail how the ELAIS survey complements other ISO surveys in
terms of depth and areal coverage, and show that the extensive multi-wavelength
coverage of the ELAIS fields resulting from our concerted and on-going
follow-up programme has made these regions amongst the best studied areas of
their size in the entire sky, and, therefore, natural targets for future
surveys. This paper accompanies the release of extremely reliable sub-sets of
the ``Preliminary Analysis'' products. Subsequent papers in this series will
give further details of our data reduction techniques, reliability &
completeness estimates and present the 15 and 90 nu number counts from the
``Preliminary Analysis'', while a further series of papers will discuss in
detail the results from the ELAIS ``Final Analysis'', as well as from the
follow-up programme.

</DOC>
<DOC>
<DOCNO> 69326 </DOCNO>
Renormalization group effect and a democratic-type neutrino mass matrix


  In our previous paper, we proposed the democratic-type neutrino mass matrix
which gives interesting predictions, $\theta_{23}=-\frac{\pi}4$, $|\tan
\theta_{12}|=\sqrt{2-3\sin^2 \theta_{13}}$ and $\delta=\frac {\pi}2$, where
$\theta_{ij}$ is the mixing angle between mass eigenstates $\nu_i$ and $\nu_j$,
and $\delta$ is the CP violation angle in the standard parameterization of
mixing matrix. In this paper, we examined how predictions behave at $m_Z$ by
assuming that they are given at the right-handed neutrino mass scale, $M_R$.

</DOC>
<DOC>
<DOCNO> 71298 </DOCNO>
Lepton Flavor Violation in Supersymmetric SO(10) Grand Unified Models


  The study for lepton flavor violation combined with the neutrino oscillation
may provide more information about the lepton flavor structure of the grand
unified theory. In this paper, we study two lepton flavor violation processes,
$\tau\to \mu\gamma$ and $Z\to \tau\mu$, in the context of supersymmetric SO(10)
grand unified models. We find the two processes are both of phenomenological
interest. In particular the latter may be important in some supersymmetric
parameter space where the former is suppressed. Thus, Z-dacay may offer another
chance for looking for lepton flavor violation.

</DOC>
<DOC>
<DOCNO> 102712 </DOCNO>
A unified representation of the q-oscillator and the q-plane


  Using deformations inspired by relativistic considerations and phase space
symmetry, we deform the position and momentum operators in one dimension. The
resulting algebra is shown to yield the q-oscillator algebra in one limiting
case and the q-plane commutation relation in another.

</DOC>
<DOC>
<DOCNO> 70391 </DOCNO>
Extra dimensions present a new flatness problem


  There is no known fundamental reason to demand as a cosmological initial
condition that the bulk possess an SO(3,1) isometry. On the contrary, one
expects bulk curvature terms that violate the SO(3,1) isometry at early epochs,
leading to a violation of Lorentz invariance on our brane. Demanding that the
Lorentz noninvariant terms are small leads to a new ``flatness'' problem, not
solved by the usual formulation of inflation. Furthermore, unlike in four
dimensions, the Lorentz violations induced from the bulk curvature cannot
always be removed as the infrared cutoff is taken arbitrarily large. This means
that the equivalence principle in higher dimensions does not guarantee the
equivalence principle in dimensionally reduced theories. Near-future
experiments are expected to severely constrain these Lorentz-violating
``signatures'' of extra dimensions.

</DOC>
<DOC>
<DOCNO> 84353 </DOCNO>
Gravitational Couplings of Intrinsic Spin


  The gravitational couplings of intrinsic spin are briefly reviewed. A
consequence of the Dirac equation in the exterior gravitational field of a
rotating mass is considered in detail, namely, the difference in the energy of
a spin-1/2 particle polarized vertically up and down near the surface of a
rotating body is $\hbar\Omega\sin\theta$. Here $\theta$ is the latitude and
$\Omega = 2GJ/(c^2 R^3)$, where $J$ and $R$ are, respectively, the angular
momentum and radius of the body. It seems that this relativistic quantum
gravitational effect could be measurable in the foreseeable future.

</DOC>
<DOC>
<DOCNO> 12163 </DOCNO>
Kinetics of exciton photoluminescence in type-II semiconductor


  The exciton decay rate at a rough interface in type-II semiconductor
superlattices is investigated. It is shown that the possibility of
recombination of indirect excitons at a plane interface essentially affects
kinetics of the exciton photoluminescence at a rough interface. This happens
because of strong correlation between the exciton recombination at the plane
interface and at the roughness. Expressions that relate the parameters of the
luminescence kinetics with statistical characteristics of the rough interface
are obtained. The mean height and length of roughnesses in GaAs/AlAs
superlattices are estimated from the experimental data.

</DOC>
<DOC>
<DOCNO> 39867 </DOCNO>
Neutralino Dark Matter in Focus Point Supersymmetry


  In recent work, it has been argued that multi-TeV masses for scalar
superpartners are not unnatural. Indeed, they appear to have significant
phenomenological virtues. Here we explore the implications of such `focus
point' supersymmetry for the dark matter problem. We find that constraints on
relic densities do not place upper bounds on neutralino or scalar masses. We
demonstrate that, in the specific context of minimal supergravity, a
cosmologically stable mixed gaugino-Higgsino state emerges as an excellent,
robust dark matter candidate. We estimate that, over a wide range of the
unknown parameters, the spin-independent proton-neutralino cross sections fall
in the range accessible to planned search experiments.

</DOC>
<DOC>
<DOCNO> 69730 </DOCNO>
Four neutrino oscillation analysis of the Superkamiokande atmospheric


  Superkamiokande atmospheric neutrino data (contained and upward going through
$\mu$ events) for 990 days are analyzed in the framework of four neutrinos
(three active and one sterile neutrinos) without imposing constraints of Big
Bang Nucleosynthesis. It is shown that the wide range of the oscillation
parameters is allowed at 90% confidence level ($0.1\lesssim
|U_{s1}|^2+|U_{s2}|^2\le 1$), where the best fit point has some contribution of
$\nu_\mu\leftrightarrow\nu_s$ and contribution of $\Delta m^2_{\rm\scriptsize
LSND}$. The case of pure $\nu_\mu\leftrightarrow\nu_s$ oscillation is excluded
at 99.7%CL (3.0$\sigma$) which is consistent with the recent analysis by the
Superkamiokande group. Combining this result with the analysis by Giunti,
Gonzarez-Garcia and Pe\~na-Garay, it is found that the Large Mixing Angle and
Vacuum Oscillation solutions of the solar neutrino problem are also allowed.

</DOC>
<DOC>
<DOCNO> 100774 </DOCNO>
Acceleration Waves in the von Karman Plate Theory


  In the present work we study acceleration waves in plate-like bodies using
the balance laws for the time-dependent von Karman equations presented in [P.
A. Djondjorov and V. M. Vassilev, Conservation Laws and Group-Invariant
Solutions of the von Karman Equations, Int. J. Nonlinear Mech. 31 (1), pp.
73-87, (1986)]. Two of these balance laws correspond to the time-dependent von
Karman equations themselves. They are used to define acceleration waves in thin
isotropic elastic plates as discontinuity solutions with finite jumps of second
derivatives of the displacement field at a certain curve - the wave front.
These two balance laws lead through Hadamard's lemma and Kotchin's theorem to a
set of jump conditions on the wave front. Similarly, the other balance laws
lead to additional and independent jump conditions on the curve of
discontinuity. Several examples are given to illustrate the effect of involving
jump conditions of that kind in analysis of acceleration waves in plates. The
examples are composed on the basis of three families of group-invariant
solutions to the time-dependent von Karman equations. They present three kinds
of waveforms pertaining to the class of the so-called relatively undistorded
progressive waves. We analyze the propagation of this special kind of
acceleration waves into a known state of plate motion.

</DOC>
<DOC>
<DOCNO> 13490 </DOCNO>
Phase Transitions of Soluble Surfactants at a Liquid-Vapor Interface


  Although medium chain length insoluble amphiphiles are well known to form
gaseous and liquid expanded phases on an air/water interface, the situation for
the soluble case is less clear. We perform molecular dynamics simulations of
model surfactant molecules dissolved in a bulk liquid solvent in coexistence
with its vapor. Our results indicate a transition in both soluble and insoluble
surfactants: a plateau in surface tension vs. surface coverage, whose
instantaneous configurations display two phase coexistence, along with
correlation functions indicating a transition to gaseous to liquid-like
behavior.

</DOC>
<DOC>
<DOCNO> 69593 </DOCNO>
Heavy-Meson Observables via Dyson-Schwinger Equations


  We summarise a Dyson-Schwinger-equation-based calculation of an extensive
range of light- and heavy-meson observables, characterised by heavy-meson
leptonic decays, semileptonic heavy-to-heavy and heavy-to-light transitions,
radiative and strong decays, and the rare flavour-changing neutral-current
process. In the calculation the heavy-quark mass functions are approximated by
constants, interpreted as their constituent mass.

</DOC>
<DOC>
<DOCNO> 70549 </DOCNO>
Primordial magnetic fields from metric perturbations


  We study the amplification of electromagnetic vacuum fluctuations induced by
the evolution of scalar metric perturbations at the end of inflation. Such
perturbations break the conformal invariance of Maxwell equations in
Friedmann-Robertson-Walker backgrounds and allow the growth of magnetic fields
on super-Hubble scales. We relate the strength of the fields generated by this
mechanism with the power spectrum of scalar perturbations and estimate the
amplification on galactic scales for different values of the spectral index.
Finally we discuss the possible effects of finite conductivity during
reheating.

</DOC>
<DOC>
<DOCNO> 100605 </DOCNO>
Compatible Poisson brackets of hydrodynamic type


  Some general properties of compatible Poisson brackets of hydrodynamic type
are discussed, in particular:
  (1) an invariant differential-geometric criterion of the compatibility based
on the Nijenhuis tensor;
  (2) the Lax pair with a spectral parameter governing compatible Poisson
brackets in the diagonalizable case;
  (3) the connection of this problem with the class of surfaces in Euclidean
space which possess nontrivial deformations preserving the Weingarten operator.

</DOC>
<DOC>
<DOCNO> 84110 </DOCNO>
Covariant two-point function for linear gravity in de Sitter space


  The Wightman two-point function for the gravitational field in the linear
approximation (the rank-2 ``massless'' tensor field) on de Sitter space has a
pathological behaviour for large separated points (infrared divergence). This
behaviour can be eliminated in the two-point function for the traceless part of
this field if one chooses the Gupta-Bleuler vacuum. But it is not possible to
do the same for the pure trace part (conformal sector). We briefly discuss the
consequences of this pure trace behaviour for inflationary models.

</DOC>
<DOC>
<DOCNO> 83059 </DOCNO>
RED behavior with different packet sizes


  We consider the adaptation of random early detection (RED) as a buffer
management algorithm for TCP traffic in Internet gateways where different
maximum transfer units (MTUs) are used. We studied the two RED variants
described in [4] and point out a weakness in both. The first variant where drop
probability is independent from the packet size discriminates connections with
smaller MTUs. The second variant results in a very high packet loss ratio
(PLR), and as a consequence low goodput, for connections with higher MTUs. We
show that fairness in terms of loss and goodput can be supplied through an
appropriate setting of the RED algorithm.

</DOC>
<DOC>
<DOCNO> 13786 </DOCNO>
Knots and Random Walks in Vibrated Granular Chains


  We study experimentally statistical properties of the opening times of knots
in vertically vibrated granular chains. Our measurements are in good
qualitative and quantitative agreement with a theoretical model involving three
random walks interacting via hard core exclusion in one spatial dimension. In
particular, the knot survival probability follows a universal scaling function
which is independent of the chain length, with a corresponding diffusive
characteristic time scale. Both the large-exit-time and the small-exit-time
tails of the distribution are suppressed exponentially, and the corresponding
decay coefficients are in excellent agreement with the theoretical values.

</DOC>
<DOC>
<DOCNO> 83161 </DOCNO>
Detecting Unsolvable Queries for Definite Logic Programs


  In solving a query, the SLD proof procedure for definite programs sometimes
searches an infinite space for a non existing solution. For example, querying a
planner for an unreachable goal state. Such programs motivate the development
of methods to prove the absence of a solution. Considering the definite program
and the query ``<- Q'' as clauses of a first order theory, one can apply model
generators which search for a finite interpretation in which the program
clauses as well as the clause ``false <- Q'' are true. This paper develops a
new approach which exploits the fact that all clauses are definite. It is based
on a goal directed abductive search in the space of finite pre-interpretations
for a pre-interpretation such that ``Q'' is false in the least model of the
program based on it. Several methods for efficiently searching the space of
pre-interpretations are presented. Experimental results confirm that our
approach find solutions with less search than with the use of a first order
model generator.

</DOC>
<DOC>
<DOCNO> 100194 </DOCNO>
Ray Singer Analytic Torsion of CY Manifolds II


  In this paper we construct the analogue of Dedekind eta function for odd
dimensional CY manifolds. We use the theory of determinant line bundles. We
constructed a canonical holomorphic section $\eta^{N}$ of some power of the
determinant line bundle on the moduli space of odd dimensional CY manifolds.
  According to Viehweg the moduli space of moduli space of polarized odd
dimensional CY manifolds $\mathcal{M}(M)$ is quasi projective. According to a
Theorem due to Hironaka we can find a projective smooth variety $\bar
{\mathcal{M}(M)}$ such that $\bar{\mathcal{M}(M)}\backslash$
$\mathcal{M}(M)=\mathcal{D}_{\infty}$ is a divisor of normal crossings. We also
showed by using Mumford's theory of metrics with logarithmic growths that the
determinant line bundle can be canonically prolonged to $\bar {\mathcal{M}(M)}$
$.$ We also showed that there exists section $\eta$ of some power of the
determinant line bundle which vanishes on $\mathcal{D}_{\infty}$ and has a
Quillen norm the Ray Singer Analytic Torsion$.$ This section is that analogue
of the Dedekind eta Function $\eta.$

</DOC>
<DOC>
<DOCNO> 151555 </DOCNO>
Non-BPS D-branes on a Calabi-Yau Orbifold


  A system containing a pair of non-BPS D-strings of type IIA string theory on
an orbifold, representing a single D2-brane wrapped on a nonsupersymmetric
2-cycle of a Calabi-Yau 3-fold with $(h^{(1,1)},h^{(1,2)})$ = (11,11), is
analyzed. In certain region of the moduli space the configuration is stable. We
show that beyond the region of stability the system can decay into a pair of
non-BPS D3-branes. At one point on the boundary of the region of stability,
there exists a marginal deformation which connects the system of non-BPS
D-strings to the system of non-BPS D3-branes. Across any other point on the
boundary of the region of stability, the transition from the system of non-BPS
D-strings to the system of non-BPS D3-branes is first order. We discuss the
phase diagram in the moduli space for these configurations.

</DOC>
<DOC>
<DOCNO> 68278 </DOCNO>
Heavy quark mass expansion and intrinsic charm in light hadrons


  We review the technique of heavy quark mass expansion of various operators
made of heavy quark fields using a semiclassical approximation. It corresponds
to an operator product expansion in the form of series in the inverse heavy
quark mass. This technique applied recently to the axial current is used to
estimate the charm content of the \eta, \eta' mesons and the intrinsic charm
contribution to the proton spin. The derivation of heavy quark mass expansion
for Qbar \gamma_5 Q is given here in detail and the expansions of the scalar,
vector and tensor current and of a contribution to the energy-momentum tensor
are presented as well. The obtained results are used to estimate the intrinsic
charm contribution to various observables.

</DOC>
<DOC>
<DOCNO> 69926 </DOCNO>
Photo-Transmutation of Leptons


  By photo-transmutation of leptons we mean photon-lepton reactions of the
following type: $\gamma l_\alpha \longrightarrow \gamma l_\beta$ with $l_\alpha
\neq l_\beta$, occurring as a consequence of the lepton mass matrix changing
its orientation (rotating) under changing scales. In this paper, we first
discuss these reactions in general terms, then proceed to the calculation of
their cross sections in two specific schemes, one within the framework of the
conventional Standard Model, the other being the so-called Dualized Standard
Model we ourselves advocate. Although the cross section obtained is generally
small the calculation reveals certain special circumstances where these
reactions may be accessible to experiment, for example with virtual photons in
LEP for $\gamma e \longrightarrow \gamma \tau$, and in BEPC for $\gamma e
\longrightarrow \gamma \mu$.

</DOC>
<DOC>
<DOCNO> 99986 </DOCNO>
La correspondance de Langlands sur les corps de fonctions [d'apr\`es


  This is the text of a Bourbaki lecture that I gave on March 12, 2000.

</DOC>
<DOC>
<DOCNO> 68639 </DOCNO>
Electroproduction of pseudoscalar mesons on the deuteron


  A general analysis of polarization phenomena for coherent meson
electroproduction on deuterons, $e+ d\to e+ d +P^0$, where $P^0$ is a
pseudoscalar $\pi ^0$ or $\eta$-meson, is presented. The spin structure of the
electromagnetic current for $P^0$-production at threshold is parametrized in
terms of specific (inelastic) threshold electromagnetic form factors which
depend on the momentum transfer squared and the effective mass of the produced
hadronic system. We give expressions for the structure functions of the
reaction $e+\vec{d}\to e +d+ P^0$ (where the deuteron target is polarized) in
terms of these threshold form factors. The spin and isospin structures of the
$\gamma ^{*}+d\to d+P^0$ amplitudes (where $\gamma ^*$ is a virtual photon) is
established in the framework of the impulse approximation and relationships
between meson electroproduction on deuterons and on nucleons are given. The
reaction of $\pi^0$ electroproduction on deuterons is investigated in detail
both at threshold and in the region of $\Delta $-isobar excitation, using the
effective Lagrangian approach for the calculation of the amplitudes of the
elementary process $\gamma^*+N\to N+\pi$. Special attention is devoted to the
analysis of all standard contributions to the exclusive cross section for
$d(e,e\pi^0)d$, which are functions of the momentum transfer square, $k^2$, of
the excitation energy of the produced hadrons and of the pion production angle,
in a region of relatively large momentum transfer. The sensitivity of these
contributions to different parametrizations of the $\gamma^*\pi\omega$ form
factor as well as to the choice of $NN-$potential is discussed.

</DOC>
<DOC>
<DOCNO> 13084 </DOCNO>
On the factors affecting the high temperature insulator-metal transition


  The measurement of resistivity across a wide temperature range - from 15 to
1473 K - in rare-earth manganite series of compounds reveals a very interesting
feature : normally observed insulating pattern beyond Tc (Curie Point) gives
way to a reentrant metallic pattern around a characteristic temperature T*. The
transport activation barrier Ea collapses to zero around T*. T* is found to be
dependent on the carrier concentration or the concentration of the
Jahn-Teller-active Mn(3+) ions as well as on the average A-site radius <rA> for
a fixed carrier concentration. These factors govern the effective lattice
distortion and hence lead to the variation in the conduction bandwidth. Our
data cover a wide range - from T*>>Tc for smaller bandwidth to T* tending
towards Tc for larger bandwidth. These results seem to provide evidence of the
onset of lattice distortion at high temperature (around T*) and its variation.
Since lattice distortion governs the magnetic, transport and other important
behaviors significantly, our data assume importance as they offer a new measure
of the effective distortion and its tunability.

</DOC>
<DOC>
<DOCNO> 40239 </DOCNO>
Intermediate mass strangelets are positively charged


  For a limited range of parameters, stable strange quark matter may be
negatively charged in bulk due to one gluon exchange interactions. However, the
reduction in strange quark occupation in the surface layer, which is
responsible for surface tension, more than compensates this for intermediate
mass strangelets, which therefore always have positive quark charge (e.g. for
baryon number between 10^2 and 10^{18} assuming alpha_S=0.9). While details are
sensitive to the choice of renormalisation, the general conclusion is not. This
rules out a scenario where negatively charged strangelets produced in
ultrarelativistic heavy ion colliders might grow indefinitely with potentially
disastrous consequences.

</DOC>
<DOC>
<DOCNO> 40322 </DOCNO>
Event-by-event fluctuations of the kaon to pion ratio in central Pb+Pb


  We present the first measurement of fluctuations from event to event in the
production of strange particles in collisions of heavy nuclei. The ratio of
charged kaons to charged pions is determined for individual central Pb+Pb
collisions. After accounting for the fluctuations due to detector resolution
and finite number statistics we derive an upper limit on genuine
non-statistical fluctuations, perhaps related to a first or second order QCD
phase transition. Such fluctuations are shown to be very small.

</DOC>
<DOC>
<DOCNO> 9570 </DOCNO>
Quantum Dot between two Superconductors


  Novel effects emerge from an interplay between multiple Andreev reflections
and Coulomb interaction in quantum dot coupled to superconducting leads and
subject to a finite potential bias $V$. Combining an intuitive physical picture
with rigorous path integral formalism we evaluate the current $I$ through the
dot and find that the interaction shifts the subharmonic pattern of the $I-V$
curve is shifted toward higher $V$. For sufficiently ^M strong interaction the
subgap current (at $eV < 2 \Delta$) is virtually suppressed.

</DOC>
<DOC>
<DOCNO> 72008 </DOCNO>
Mott effect at the chiral phase transition and anomalous J/Psi


  We investigate the in-medium modification of the charmonium break-up
processes due to the Mott effect for light (pi) and open-charm (D, D*) mesons
at the chiral/deconfinement phase transition. A model calculation for the
process J/Psi + pi -> D + \bar D* + h.c. is presented which demonstrates that
the Mott effect for the D-mesons leads to a threshold effect in the thermal
averaged break-up cross section. This effect is suggested as an explanation of
the phenomenon of anomalous J/Psi suppression in the CERN NA50 experiment.

</DOC>
<DOC>
<DOCNO> 9316 </DOCNO>
Thermopower in p-type GaAs/AlGaAs layers


  We explain for the first time thermopower data for p-type GaAs/AlGaAs layers.
The data span a temperature range between 0.2 to 1.2K. We calculate both the
diffusion $S^{d}$ and the phonon-drag $S^{g}$ contributions to the thermopower.
We find that $S^{d}$ is significant for temperatures up to 0.3K while at higher
temperatures $S^{g}$ dominates. The calculated and measured $S^{g}$ agree very
well with no adjustable parameters.

</DOC>
<DOC>
<DOCNO> 12716 </DOCNO>
Breakdown of the Internet under intentional attack


  We study the tolerance of random networks to intentional attack, whereby a
fraction p of the most connected sites is removed. We focus on scale-free
networks, having connectivity distribution of P(k)~k^(-a) (where k is the site
connectivity), and use percolation theory to study analytically and numerically
the critical fraction p_c needed for the disintegration of the network, as well
as the size of the largest connected cluster. We find that even networks with
a<=3, known to be resilient to random removal of sites, are sensitive to
intentional attack. We also argue that, near criticality, the average distance
between sites in the spanning (largest) cluster scales with its mass, M, as
sqrt(M), rather than as log_k M, as expected for random networks away from
criticality. Thus, the disruptive effects of intentional attack become relevant
even before the critical threshold is reached.

</DOC>
<DOC>
<DOCNO> 69657 </DOCNO>
B_s \to \ell^+ \ell^- in a model II 2HDM and MSSM


  In this paper we analyze the process $B_s \to \ell^+ \ell^-$ in a model II
2HDM and MSSM. All the leading terms of Wilson coefficients relevant to the
process are given in the large tan$\beta$ limit. It is shown that the decay
width for $B_s \to \ell^+ \ell^-$ depends on all parameters except $m_{A^0}$ in
the 2HDM. The branching ratio of $B_s \to \mu^+ \mu^-$ can reach its
experimental bound in some large tan$\beta$ regions of the parameter space in
MSSM because the amplitude increases like tan$^3\beta$ in the regions. For
l=$\tau$, the branching ratio can even reach $10^{-4}$ in the regions.
Therefore, the experimental measurements of leptonic decays of $B_s$ could put
a constraint on the contributions of neutral Higgs bosons and consequently the
parameter space in MSSM.

</DOC>
<DOC>
<DOCNO> 169826 </DOCNO>
Quantum Fluctuations of a Single Trapped Atom: Transient Rabi


  Isolation of a single atomic particle and monitoring its resonance
fluorescence is a powerful tool for studies of quantum effects in
radiation-matter interaction. Here we present observations of quantum dynamics
of an isolated neutral atom stored in a magneto-optical trap. By means of
photon correlations in the atom's resonance fluorescence we demonstrate the
well-known phenomenon of photon antibunching which corresponds to transient
Rabi oscillations in the atom. Through polarization-sensitive photon
correlations we show a novel example of resolved quantum fluctuations:
spontaneous magnetic orientation of an atom. These effects can only be observed
with a single atom.

</DOC>
<DOC>
<DOCNO> 8585 </DOCNO>
Multifractal Properties of the Random Resistor Network


  We study the multifractal spectrum of the current in the two-dimensional
random resistor network at the percolation threshold. We consider two ways of
applying the voltage difference: (i) two parallel bars, and (ii) two points.
Our numerical results suggest that in the infinite system limit, the
probability distribution behaves for small current i as P(i) ~ 1/i. As a
consequence, the moments of i of order q less than q_c=0 do not exist and all
current of value below the most probable one have the fractal dimension of the
backbone. The backbone can thus be described in terms of only (i) blobs of
fractal dimension d_B and (ii) high current carrying bonds of fractal dimension
going from $1/\nu$ to d_B.

</DOC>
<DOC>
<DOCNO> 101338 </DOCNO>
On the computation of spectra in free probability


  We use free probability techniques to compute borders of spectra of non
hermitian operators in finite von Neumann algebras which arise as `free sums'
of `simple' operators. To this end, the resolvent is analyzed with the aid of
the Haagerup inequality. Concrete examples coming from reduced C*-algebras of
free product groups and leading to systems of polynomial equations illustrate
the approach.

</DOC>
<DOC>
<DOCNO> 121781 </DOCNO>
Theoretical expectations for clump red giants as distance indicators


  Variations of ~0.4 mag are expected in the I-band absolute magnitude of red
clump giants, M_I^RC, as a function of both stellar age and metallicity. This
regardless of some potential theoretical uncertainties. Due to the quite large
differences in mean ages and metallicities of clump stars among galaxies,
systematic changes (also amounting up to ~0.4 mag) come out in their M_I^RC.
These numbers also indicate a distance to the LMC that is not necessarily
``short''.

</DOC>
<DOC>
<DOCNO> 68346 </DOCNO>
Partially Quenched Chiral Perturbation Theory and the Replica Method


  We describe a novel framework for partially quenched chiral perturbation
theory based on the replica method. The computational rules are exceedingly
simple. We illustrate these rules by computing the partially quenched chiral
condensate to one-loop order. By considering arbitrary chiral $k$-point
functions we show explicitly to one-loop order the equivalence between this
method and the one based on supersymmetry. It is possible to go smoothly from
the conventional replica method to a supersymmetric variant by choosing the
number of valence quarks to be negative.

</DOC>
<DOC>
<DOCNO> 70234 </DOCNO>
Scenario for Ultrarelativistic Nuclear Collisions: II. Geometry of


  We suggest that the ultrarelativistic collisions of heavy ions provide the
simplest situation for the study of strong interactions which can be understood
from first principles and without any model assumptions about the microscopic
structure of the colliding nuclei. We argue that the boost-invariant geometry
of the collision, and the existence of hard partons in the final states, both
supported by the data, make a sufficient basis for the quantum theory of the
phenomenon. We conclude that the quantum nature of the entire process is
defined by its global geometry, which is enforced by a macroscopic finite size
of the colliding objects. In this paper, we study the qualitative aspects of
the theory and review its development in two subsequent papers. Our key result
is that the effective mass of the quark in the expanding system formed in the
collision of the two nuclei is gradually built up reaching its maximum by the
time the quark mode becomes sufficiently localized. The chromo-magneto-static
interaction of the color currents flowing in the rapidity direction is the main
mechanism which is responsible for the generation of the effective mass of the
soft quark mode and therefore, for the physical scale at the earliest stage of
the collision.

</DOC>
<DOC>
<DOCNO> 101838 </DOCNO>
Deformation Quantization of Hermitian Vector Bundles


  Motivated by deformation quantization, we consider in this paper
$^*$-algebras $\mathcal A$ over rings $\ring C = \ring{R}(i)$, where $\ring R$
is an ordered ring and $i^2 = -1$, and study the deformation theory of
projective modules over these algebras carrying the additional structure of a
(positive) $\mathcal A$-valued inner product. For $A=C^\infty(M)$, M a
manifold, these modules can be identified with Hermitian vector bundles E over
M. We show that for a fixed Hermitian star-product on M, these modules can
always be deformed in a unique way, up to (isometric) equivalence. We observe
that there is a natural bijection between the sets of equivalence classes of
local Hermitian deformations of $C^\infty(M)$ and $\Gamma^\infty(\End(E))$ and
that the corresponding deformed algebras are formally Morita equivalent, an
algebraic generalization of strong Morita equivalence of $C^*$-algebras. We
also discuss the semi-classical geometry arising from these deformations.

</DOC>
<DOC>
<DOCNO> 84514 </DOCNO>
Evidence for a null entropy of extremal black holes


  We present some arguments in support of a {\it zero} entropy for {\it
extremal} black holes. These rely on a combination of both quantum,
thermodynamic, and statistical physics arguments. This result may shed some
light on the nature of these extreme objects. In addition, we show that within
a {\it quantum} framework the capture of a particle by an initially extremal
black hole always results with a final nonextremal black hole.

</DOC>
<DOC>
<DOCNO> 85405 </DOCNO>
Projective Relativity: Present Status and Outlook


  We give a critical analysis of projective relativity theory. Examining
Kaluza's own intention and the following development by Klein, Jordan, Pauli,
Thiry, Ludwig and others, we conclude that projective relativity was abused in
its own terms. Much more in the case of newer higher dimensional Kaluza--Klein
theories with non-Abelian gauge groups. Reviewing the projective formulation of
the Jordan isomorphy theorem yields some hints how one can proceed in a
different direction. We can interpret the condition R5_{\mu\nu}=0 not as a
field equation in a 5-dimensional Riemannian space, e.g. as vacuum
Einstein-Hilbert equation, but can (or should) interpret it as a geometrical
object, a null-quadric. Projective aspects of quantum (field) theory are
discussed under this viewpoint.

</DOC>
<DOC>
<DOCNO> 116475 </DOCNO>
Dirac monopole with Feynman brackets


  We introduce the magnetic angular momentum as a consequence of the structure
of the sO(3) Lie algebra defined by the Feynman brackets. The Poincare momentum
and Dirac magnetic monopole appears as a direct result of this framework.

</DOC>
<DOC>
<DOCNO> 9398 </DOCNO>
Magnetization and Level Statistics at Quantum Hall Liquid-Insulator


  Statistics of level spacing and magnetization are studied for the phase
diagram of the integer quantum Hall effect in a 2D finite lattice model with
Anderson disorder.

</DOC>
<DOC>
<DOCNO> 170737 </DOCNO>
Multi-bit gates for quantum computing


  We present a general technique to implement products of many qubit operators
communicating via a joint harmonic oscillator degree of freedom in a quantum
computer. By conditional displacements and rotations we can implement
Hamiltonians which are trigonometric functions of qubit operators. With such
operators we can effectively implement higher order gates such as Toffoli gates
and C^n-NOT gates, and we show that the entire Grover search algorithm can be
implemented in a direct way.

</DOC>
<DOC>
<DOCNO> 150516 </DOCNO>
The Majorana particles and the Majorana sea


  Can one make a Majorana field theory for fermions starting from the zero mass
Weyl theory, then adding a mass term as an interaction? The answer to this
question is: yes we can. We can proceed similarly to the case of the Dirac
massive field theory. In both cases one can start from the zero mass Weyl
theory and then add a mass term as an interacting term of massless particles
with a constant (external) field. In both cases the interaction gives rise to a
field theory for a free massive fermion field. We present the procedure for the
creation of a mass term in the case of the Dirac and the Majorana field and we
look for a massive field as a superposition of massless fields.

</DOC>
<DOC>
<DOCNO> 7910 </DOCNO>
Density Wave States of Non-Zero Angular Momentum


  We study the properties of states in which particle-hole pairs of non-zero
angular momentum condense. These states generalize charge- and
spin-density-wave states, in which s-wave particle-hole pairs condense. We show
that the p-wave spin-singlet state of this type has Peierls ordering, while the
d-wave spin-singlet state is the staggered flux state. We discuss model
Hamiltonians which favor p-wave and d-wave density wave order. There are
analogous orderings for pure spin models, which generalize spin-Peierls order.
The spin-triplet density wave states are accompanied by spin-1 Goldstone
bosons, but these excitations do not contribute to the spin-spin correlation
function. Hence, they must be detected with NQR or Raman scattering
experiments. Depending on the geometry and topology of the Fermi surface, these
states may admit gapless fermionic excitations. As the Fermi surface geometry
is changed, these excitations disappear at a transition which is third-order in
mean-field theory. The singlet d-wave and triplet p-wave density wave states
are separated from the corresponding superconducting states by zero-temperature
O(4)-symmetric critical points

</DOC>
<DOC>
<DOCNO> 70023 </DOCNO>
K0 form factor at order p^6 of chiral perturbation theory


  This paper describes the calculation of the electromagnetic form factor of
the K0 meson at order p^6 of chiral perturbation theory which is the
next-to-leading order correction to the well-known p^4 result achieved by
Gasser and Leutwyler. On the one hand, at order p^6 the chiral expansion
contains 1- and 2-loop diagrams which are discussed in detail. Especially, a
numerical procedure for calculating the irreducible 2-loop graphs of the sunset
topology is presented. On the other hand, the chiral Lagrangian L^6 produces a
direct coupling of the K0 current with the electromagnetic field tensor. Due to
this coupling one of the unknown parameters of L^6 occurs in the contribution
to the K0 charge radius.

</DOC>
<DOC>
<DOCNO> 13359 </DOCNO>
Interaction effects and the metallic phase in p-SiGe


  Magnetoresistance results are presented for p-SiGe samples on the metallic
side of the B=0 metal-insulator transition. The results cannot be understood
within the framework of standard theories for quantum corrections of a weakly
interacting 2- dimensional system. In particular no logarithmic dependence on
temperature is observed, at low fields, in either the longitudinal or Hall
resistivities despite evidence in the magnetoresistance of weak localisation
effects. Further, the Hall coefficient shows a strong logarithmic dependence on
field. The results are better explain by renormalisation group theories and by
an anomalous Hall effect associated with strong spin-orbit coupling in the
presence of a background spin texture.

</DOC>
<DOC>
<DOCNO> 10522 </DOCNO>
Magneto-Transport properties in the thin films of Charge ordered thin


  Thin films of Pr0.7Ca 0.3MnO3, Nd-0.5Ca0.5MnO3 and Nd0.5Sr0.5MnO3 have been
fabricated. by pulse laser deposition. Magnetic and electrical transport
properties of these films were compared with their bulk solids. All the films
grow in (101) direction on LaAlO3(100). Electrical transport measurements
carried out with and without magnetic field has shown dr/dT<0 in these thin
films. Application of magnetic field has shown dilution of the insulating
behavior. The magnetization studies of Nd-0.5Sr0.5MnO3 exhibited ferromagnetic
behavior at 260K and showed antiferomagnetic feature below 130K. This is close
to the bulk magnetic behavior of Nd-0.5Sr0.5MnO3. Pr0.7Ca0.3MnO3 showed
ferromagnetic transition below 130K and becomes antiferromagnetic at 90K.
Nd-0.5Ca0.5MnO3 showed paramagnetic behavior down to low temperatures.
Deviation in the properties of the thin films from the bulk solids is
attributed to the growth of the films in more symmetric structure.

</DOC>
<DOC>
<DOCNO> 8919 </DOCNO>
The relaxation dynamics of a simple glass former confined in a pore


  We use molecular dynamics computer simulations to investigate the relaxation
dynamics of a binary Lennard-Jones liquid confined in a narrow pore. We find
that the average dynamics is strongly influenced by the confinement in that
time correlation functions are much more stretched than in the bulk. By
investigating the dynamics of the particles as a function of their distance
from the wall, we can show that this stretching is due to a strong dependence
of the relaxation time on this distance, i.e. that the dynamics is spatially
very heterogeneous. In particular we find that the typical relaxation time of
the particles close to the wall is orders of magnitude larger than the one of
particles in the center of the pore.

</DOC>
<DOC>
<DOCNO> 13894 </DOCNO>
Electronic Transmission Through Metallic Nanowires: Generalized


  An easy to implement and powerful method for the solution of 3D scattering
problems that can be well described by Helmholtz equation is presented. The
matrix algebra used provides excellent stability versus the number of junctions
as well as great computational speed. The matrix truncation method yields an
easy single-parameter convergence procedure. Subsequently, some aspects of the
electronic transport through metal nanowires are studied by the use of
Landauer's scattering approach to the conductance. We predict the existence of
current vortex-rings patterns due to sharp enough narrow-wide connections in
atomic size point contacts. Longitudinal resonances between scattering centers
provide a simple physical picture for the understanding of negative
differential resistance in ideal monoatomic contacts. Relatively long nanowires
with high geometrical perfection -like those recently observed by Transmission
Electron Microscopy- are modelled exhibiting resonant tunnelling and total
reflection at given incident energy intervals.

</DOC>
<DOC>
<DOCNO> 102445 </DOCNO>
On the uniqueness of AF diagonals in regular limit algebras


  Necessary and sufficient conditions are obtained for the uniqueness of
standard regular AF masas in regular limit algebras up to approximate inner
unitary equivalence.

</DOC>
<DOC>
<DOCNO> 12967 </DOCNO>
Simplification of thermodynamic Bethe-ansatz equations


  Thermodynamic Bethe ansatz equations for XXZ model at $|\Delta|\ge 1$ is
simplified to an integral equation which has one unknown function. This
equation is analytically continued to $|\Delta|<1$.

</DOC>
<DOC>
<DOCNO> 170650 </DOCNO>
On the reversible extraction of classical information from a quantum


  Consider a source E of pure quantum states with von Neumann entropy S. By the
quantum source coding theorem, arbitrarily long strings of signals may be
encoded asymptotically into S qubits/signal (the Schumacher limit) in such a
way that entire strings may be recovered with arbitrarily high fidelity.
Suppose that classical storage is free while quantum storage is expensive and
suppose that the states of E do not fall into two or more orthogonal subspaces.
We show that if E can be compressed with arbitrarily high fidelity into A
qubits/signal plus any amount of auxiliary classical storage then A must still
be at least as large as the Schumacher limit S of E. Thus no part of the
quantum information content of E can be faithfully replaced by classical
information. If the states do fall into orthogonal subspaces then A may be less
than S, but only by an amount not exceeding the amount of classical information
specifying the subspace for a signal from the source.

</DOC>
<DOC>
<DOCNO> 99702 </DOCNO>
A complete bounded minimal cylinder in R^3


  In 1996, Nadirashvili used Runge's theorem to produce a complete minimal disc
inside a ball in R^3. In this paper we generalize the techniques used by
Nadirashvili to obtain new examples of complete minimal surfaces inside a ball
in R^3, with the conformal structure of an annulus.

</DOC>
<DOC>
<DOCNO> 10855 </DOCNO>
Critical behavior at m-axial Lifshitz points: field-theory analysis and


  The critical behavior of d-dimensional systems with an n-component order
parameter is reconsidered at (m,d,n)-Lifshitz points, where a wave-vector
instability occurs in an m-dimensional subspace of ${\mathbb R}^d$. Our aim is
to sort out which ones of the previously published partly contradictory
$\epsilon$-expansion results to second order in $\epsilon=4+\frac{m}{2}-d$ are
correct. To this end, a field-theory calculation is performed directly in the
position space of $d=4+\frac{m}{2}-\epsilon$ dimensions, using dimensional
regularization and minimal subtraction of ultraviolet poles. The residua of the
dimensionally regularized integrals that are required to determine the series
expansions of the correlation exponents $\eta_{l2}$ and $\eta_{l4}$ and of the
wave-vector exponent $\beta_q$ to order $\epsilon^2$ are reduced to single
integrals, which for general m=1,...,d-1 can be computed numerically, and for
special values of m, analytically. Our results are at variance with the
original predictions for general m. For m=2 and m=6, we confirm the results of
Sak and Grest [Phys. Rev. B {\bf 17}, 3602 (1978)] and Mergulh{\~a}o and
Carneiro's recent field-theory analysis [Phys. Rev. B {\bf 59},13954 (1999)].

</DOC>
<DOC>
<DOCNO> 121455 </DOCNO>
Composition of active galactic nuclei jets: pair-plasma dominance in the


  We investigate whether the parsec-scale jets of quasars 3C 345 and 3C 279 are
dominated by a normal (proton-electron) plasma or a pair (electron-positron)
plasma. We first present a new method to compute the kinetic luminosity of a
conical jet by using the core size observed at a single very long baseline
interferometry frequency. The deduced kinetic luminosity gives electron
densities of individual radio-emitting components as a function of the
composition. We next constrain the electron density independently by using the
theory of synchrotron self-absorption. Comparing the two densities, we can
discriminate the composition. We then apply this procedure to the five
components in the 3C 345 jet and find that they are pair-plasma dominated at 14
epochs out of the total 19 epochs at which the turnover frequencies are
reported, provided that the bulk Lorentz factor is less than 15 throughout the
jet. We also investigate the composition of the 3C 279 jet and demonstrate that
its two components are likely pair-plasma dominated at all the four epochs,
provided that their Doppler factors are less than 10, which are consistent with
observations. The conclusions do not depend on the lower cutoff energy of
radiating particles.

</DOC>
<DOC>
<DOCNO> 69873 </DOCNO>
Supersymmetric Quantum Corrections and Poisson-Lie T-Duality


  The quantum actions of the (4,4) supersymmetric non-linear sigma model and
its dual in the Abelian case are constructed by using the background superfield
method. The propagators of the quantum superfield and its dual and the gauge
fixing actions of the original and dual (4,4) supersymmetric sigma models are
determined. On the other hand, the BRST transformations are used to obtain the
quantum dual action of the (4,4) supersymmetric non-linear sigma model in the
sense of Poisson-Lie T-duality

</DOC>
<DOC>
<DOCNO> 99391 </DOCNO>
Convex lattice polytopes and cones with few lattice points inside, from


  It is pretty well-known that toric Fano varieties of dimension k with
terminal singularities correspond to convex lattice polytopes P in R^k of
positive finite volume, such that intersection of P and Z^k consists of the
point 0 and vertices of P. Likewise, Q-factorial terminal toric singularities
essentially correspond to lattice simplexes with no lattice points inside or on
the boundary (except the vertices). There have been a lot work, especially in
the last 20 years or so on classification of these objects. The main goal of
this paper is to bring together these and related results, that are currently
scattered in the literature. We also want to emphasize the deep similarity
between the problems of classification of toric Fano varieties and
classification of Q-factorial toric singularities.

</DOC>
<DOC>
<DOCNO> 85113 </DOCNO>
Gravitationally bound monopoles


  We construct monopole solutions in SU(2) Einstein-Yang-Mills-Higgs theory,
carrying magnetic charge n. For vanishing and small Higgs selfcoupling, these
multimonopole solutions are gravitationally bound. Their mass per unit charge
is lower than the mass of the n=1 monopole. For large Higgs selfcoupling only a
repulsive phase exists.

</DOC>
<DOC>
<DOCNO> 102257 </DOCNO>
A New Class of PT-symmetric Hamiltonians with Real Spectra


  We investigate complex PT-symmetric potentials, associated with quasi-exactly
solvable non-hermitian models involving polynomials and a class of rational
functions. We also look for special solutions of intertwining relations of SUSY
Quantum Mechanics providing a partnership between a real and a complex
PT-symmetric potential of the kind mentioned above. We investigate conditions
sufficient to ensure the reality of the full spectrum or, for the quasi-exactly
solvable systems, the reality of the energy of the finite number of levels.

</DOC>
<DOC>
<DOCNO> 11409 </DOCNO>
Diagrammatic theory of the Anderson impurity model with finite Coulomb


  We have developed a self-consistent conserving pseudo particle approximation
for the Anderson impurity model with finite Coulomb interaction, derivable from
a Luttinger Ward functional. It contains an infinite series of skeleton
diagrams built out of fully renormalized Green's functions. The choice of
diagrams is motivated by the Schrieffer Wolff transformation which shows that
singly and doubly occupied states should appear in all bare diagrams
symmetrically. Our numerical results for $T_K$ are in excellent agreement with
the exact values known from the Bethe ansatz solution. The low energy physics
of non-Fermi liquid Anderson impurity systems is correctly described while the
present approximation fails to describe Fermi liquid systems, since some
important coherent spin flip and charge transfer processes are not yet
included. It is believed that CTMA (Conserving T-matrix approximation) diagrams
will recover also Fermi liquid behavior for Anderson models with finite Coulomb
interaction as they do for infinite Coulomb interaction.

</DOC>
<DOC>
<DOCNO> 150414 </DOCNO>
A nilpotent symmetry of quantum gauge theories


  For the Becchi-Rouet-Stora-Tyutin (BRST) invariant extended action for any
gauge theory, there exists another off-shell nilpotent symmetry. For linear
gauges, it can be elevated to a symmetry of the quantum theory and used in the
construction of the quantum effective action. Generalizations for nonlinear
gauges and actions with higher order ghost terms are also possible.

</DOC>
<DOC>
<DOCNO> 170660 </DOCNO>
Teleportation: from probability distributions to quantum states


  The role of the off-diagonal density matrix elements of the entangled pair is
investigated in quantum teleportation of a qbit. The dependence between them
and the off-diagonal elements of the teleported density matrix is shown to be
linear. In this way the ideal quantum teleportation is related to an entirely
classical communication protocol: the one-time pad cypher. The latter can be
regarded as the classical counterpart of Bennett's quantum teleportation
scheme. The quantum-to-classical transition is demonstrated on the statistics
of a gedankenexperiment.

</DOC>
<DOC>
<DOCNO> 100437 </DOCNO>
Classification of equivariant real vector bundles over a circle


  This is a continuation of the authors' previous work [math.AT/9910001] on
classification of equivariant complex vector bundles over a circle. In this
paper we classify equivariant real vector bundles over a circle with a compact
Lie group action, by characterizing the fiber representations of them, and by
using the result of the complex case. We also treat the triviality of them. The
basic phenomenon is similar to the complex case but more complicated here.

</DOC>
<DOC>
<DOCNO> 71709 </DOCNO>
Running electromagnetic coupling constant: low energy normalization and


  A numerical value for the running electromagnetic coupling constant in the MS
scheme is calculated at the low energy normalization scale equal to the
tau-lepton mass M_\tau. This low energy boundary value is used for running the
electromagnetic coupling constant to larger scales where high precision
experimental measurements can be performed. Particular scales of interest are
the b-quark mass for studying the \Upsilon-resonance physics and the Z-boson
mass M_Z for high precision tests of the standard model and for the Higgs mass
determination from radiative corrections. A numerical value for the running
electromagnetic coupling constant at M_Z in the on-shell renormalization scheme
is also given.

</DOC>
<DOC>
<DOCNO> 122519 </DOCNO>
Mining Gamma-Ray Burst Data


  Gamma-ray bursts provide what is probably one of the messiest of all
astrophysical data sets. Burst class properties are indistinct, as overlapping
characteristics of individual bursts are convolved with effects of instrumental
and sampling biases. Despite these complexities, data mining techniques have
allowed new insights to be made about gamma-ray burst data. We demonstrate how
data mining techniques have simultaneously allowed us to learn about gamma-ray
burst detectors and data collection, cosmological effects in burst data, and
properties of burst subclasses. We discuss the exciting future of this field,
and the web-based tool we are developing (with support from the NASA AISR
Program). We invite others to join us in AI-guided gamma-ray burst
classification (http://grb.mnsu.edu/grb/).

</DOC>
<DOC>
<DOCNO> 122544 </DOCNO>
On the Probability of Microlensing in GRB Afterglows


  The declining lightcurve of the optical afterglow of gamma-ray burst
GRB000301C showed rapid variability with one particularly bright feature at
about t-t0=3.8 days. This event was interpreted as gravitational microlensing
by Garnavich, Loeb & Stanek (2000) and subsequently used to derive constraints
on the structure of the GRB optical afterglow. In this paper, we use these
structural parameters to calculate the probability of such a microlensing event
in a realistic scenario, where all compact objects in the universe are
associated with observable galaxies. For GRB000301C at a redshift of z=2.04,
the `a posteriori' probability for a microlensing event with an amplitude of
dm>=0.95 mag (as observed) is 0.7% (2.7%) for the most plausible scenario of a
flat Lambda-dominated FRW universe with Omega_m=0.3 and a fraction f_*=0.2
(1.0) of dark-matter in the form of compact objects. If we lower the
magnification threshold to dm>=0.10 mag, the probabilities for microlensing
events of GRB afterglows increase to 17% (57%). We emphasise that this low
probability for a microlensing signature of almost a magnitude does not exclude
that the observed event in the afterglow lightcurve of GRB000301C was caused by
microlensing, especially in light of the fact that a galaxy was found within 2
arcsec from the GRB. In that case, however, a more robust upper limit on the `a
posteriori' probability of ~5% is found. It does show, however, that it will
not be easy to create a large sample of strong GRB afterglow microlensing
events for statistical studies of their physical conditions on micro-arcsec
scales.

</DOC>
<DOC>
<DOCNO> 12659 </DOCNO>
Mean-Field Approach to Charge, Orbital, and Spin Ordering in Manganites


  We present a mean-field theory of charge, orbital, and spin ordering in
manganites at 50% and 0% dopings by considering Jahn-Teller interaction,
nearest-neighbor repulsion, and no single-site double occupancy. For spinless
fermions, we show that Jahn-Teller distortion and charge-orbital ordering occur
simultaneously. In our two-dimensional model at 50% doping, for small
nearest-neighbor repulsion the system is orbitally polarized while for larger
repulsion the system undergoes CE type ordering. As for the 0% doping case, the
ground state is orbitally antiferromagnetic. Upon including spin degree of
freedom, at both 50% and 0% dopings the ordering remains the same at small
antiferromagnetic coupling between adjacent core spins.

</DOC>
<DOC>
<DOCNO> 174507 </DOCNO>
Level density and thermal properties in rare earth nuclei


  A convergent method to extract the nuclear level density and the gamma-ray
strength function from primary gamma-ray spectra has been established.
Thermodynamical quantities have been obtained within the microcanonical and
canonical ensemble theory. Structures in the caloric curve and in the heat
capacity curve are interpreted as fingerprints of breaking of Cooper pairs and
quenching of pairing correlations. The strength function can be described using
models and common parameterizations for the E1, M1 and pygmy resonance
strength. However, a significant decrease of the pygmy resonance strength at
finite temperatures has been observed.

</DOC>
<DOC>
<DOCNO> 68337 </DOCNO>
On the Spectrum and Representation Theory of Non-Abelian Monopoles


  This manuscript has been withdrawn by the author. Some of the material has
been included in the manuscript 'Embedded Monopoles' at hep-th/0106254.

</DOC>
<DOC>
<DOCNO> 12495 </DOCNO>
Magnetization processes in quantum spin chains with regularly


  We consider the dependence magnetization vs. field at zero temperature for
the spin-1/2 chains in which the intersite interactions regularly vary from
site to site with a period p. In the limiting case when the smallest value of
the intersite interactions tends to zero the chain splits into noninteracting
identical fragments of p sites and the dependence magnetization vs. field can
be examined rigorously. We demonstrate explicitly the appearance of plateaus in
such dependence and discuss a presence of the magnetization values m predicted
by the condition p(1/2-m)=integer [1]. We comment on the influence of the
anisotropy in the interspin interaction on the magnetization profiles. Finally,
we show how the case of nonzero smallest value of the intersite interactions
can be considered.

</DOC>
<DOC>
<DOCNO> 70705 </DOCNO>
Constraints on the Proton's Gluon Density from Lepton-Pair Production


  Massive lepton-pair production, the Drell-Yan process, should be a good
source of independent constraints on the gluon density, free from the
experimental and theoretical complications of photon isolation that beset
studies of prompt photon production. We provide predictions for the
spin-averaged and spin-dependent differential cross sections as a function of
transverse momentum $Q_T$.

</DOC>
<DOC>
<DOCNO> 152182 </DOCNO>
On Some Positivity Properties of the Interquark Potential in QCD


  We prove that the Fourier transform of the exponential $e^{-\b V(R)}$ of the
{\bf static} interquark potential in QCD is positive. It has been shown by
Eliott Lieb some time ago that this property allows in the same limit of static
spin independent potential proving certain mass relation between baryons with
different quark flavors.

</DOC>
<DOC>
<DOCNO> 8811 </DOCNO>
Coherent and Incoherent Dynamic Structure Function of the Free Fermi Gas


  A detailed calculation of the coherent and incoherent dynamic structure
functions of the free Fermi gas, starting from their expressions in terms of
the one- and semi-diagonal two-body density matrices, is derived and discussed.
Their behavior and evolution with the momentum transfer is analyzed, and
particular attention is devoted to the contributions that both functions
present at negative energies. Finally, an analysis of the energy weighted sum
rules satisfied by both responses is also performed. Despite of the simplicity
of the model, some of the conclusions can be extended to realistic systems.

</DOC>
<DOC>
<DOCNO> 174488 </DOCNO>
New Measurement of Parity Violation in Elastic Electron-Proton


  We have measured the parity-violating electroweak asymmetry in the elastic
scattering of polarized electrons from the proton. The result is A = -15.05 +-
0.98(stat) +- 0.56(syst) ppm at the kinematic point theta_lab = 12.3 degrees
and Q^2 = 0.477 (GeV/c)^2. The measurement implies that the value for the
strange form factor (G_E^s + 0.392 G_M^s) = 0.025 +- 0.020 +- 0.014, where the
first error is experimental and the second arises from the uncertainties in
electromagnetic form factors. This measurement is the first fixed-target parity
violation experiment that used either a `strained' GaAs photocathode to produce
highly polarized electrons or a Compton polarimeter to continuously monitor the
electron beam polarization.

</DOC>
<DOC>
<DOCNO> 100438 </DOCNO>
A Time-Dependent Born-Oppenheimer Approximation with Exponentially Small


  We present the construction of an exponentially accurate time-dependent
Born-Oppenheimer approximation for molecular quantum mechanics. We study
molecular systems whose electron masses are held fixed and whose nuclear masses
are proportional to $\epsilon^{-4}$, where $\epsilon$ is a small expansion
parameter. By optimal truncation of an asymptotic expansion, we construct
approximate solutions to the time-dependent Schr\"odinger equation that agree
with exact normalized solutions up to errors whose norms are bounded by $\ds C
\exp(-\gamma/\epsilon^2)$, for some C and $\gamma>0$.

</DOC>
<DOC>
<DOCNO> 8751 </DOCNO>
Quantum Phase Transition of Hole-Doped Antiferromagnets


  This paper has been withdrawn.

</DOC>
<DOC>
<DOCNO> 170168 </DOCNO>
Stationary Flows of the Parabolic Potential Barrier in Two Dimensions


  In the two-dimensional isotropic parabolic potential barrier $V(x, y)=V_0
-m\gamma^2 (x^2+y^2)/2$, though it is a model of an unstable system in quantum
mechanics, we can obtain the stationary states corresponding to the real energy
eigenvalue $V_0$. Further, they are infinitely degenerate. For the first few
eigenstates, we will find the stationary flows round a right angle that are
expressed by the complex velocity potentials $W=\pm\gamma z^2/2$.

</DOC>
<DOC>
<DOCNO> 85110 </DOCNO>
String cosmology coupled to Weyl-integrable geometry


  The requirement that the laws of physics must be invariant under
point-dependent transformations of the units of length, time, and mass is used
as a selection principle while studying different generic effective theories of
gravity. Thereof theories with non-minimal coupling of the dilaton both to the
curvature and to the Lagrangian of the matter fields seem to represent the most
viable low-energy [and low-curvature] description of gravity. Consequently, the
cosmological singularity problem is treated within the context of string
cosmology with non-minimal coupling of the dilaton to a barotropic gas of
solitonic p-brane. The results obtained are to be interpreted on the grounds of
Weyl-integrable geometry. The implications of these results for the Mach's
principle are briefly discussed.

</DOC>
<DOC>
<DOCNO> 68527 </DOCNO>
Fluctuation Probes of Quark Deconfinement


  The size of the average fluctuations of net baryon number and electric charge
in a finite volume of hadronic matter differs widely between the confined and
deconfined phases. These differences may be exploited as indicators of the
formation of a quark-gluon plasma in relativistic heavy-ion collisions, because
fluctuations created in the initial state survive until freeze-out due to the
rapid expansion of the hot fireball.

</DOC>
<DOC>
<DOCNO> 100564 </DOCNO>
On the center of affine Hecke algebras of type A


  We give an explicit expression for the central elements of affine Hecke
algebras of type A in the Coxeter presentation, in terms of (parabolic) affine
Kazhdan-Lusztig polynomials. Our approach is based on a version of quantum
affine Schur-Weyl duality involving the Hall algebra of a cyclic quiver, on the
theory of canonical bases and on the higher-level q-deformed Fock spaces
recently introduced by Uglov.

</DOC>
<DOC>
<DOCNO> 71339 </DOCNO>
QCD analysis of $F_2^{\gamma}(x,Q^2)$: an unconventional view


  Elements of the alternative approach to hard collisions of photons, proposed
recently by the author, are reviewed, with particular attention to QCD analysis
of $F^{\gamma}_2$. This approach is based on clear separation of genuine QCD
effects from those of pure QED origin and does not rely on the assumption that
parton distribution functions of the photon behave as $\alpha/\alpha_s$. It
differs significantly from the conventional one, as illustrated on the example
of charm contribution to $F_{2}^{\gamma}$, recently measured at LEP.

</DOC>
<DOC>
<DOCNO> 13074 </DOCNO>
Anisotropic exchange interaction of localized conduction-band electrons


  The spin-orbit interaction in semiconductors is shown to result in an
anisotropic contribution into the exchange Hamiltonian of a pair of localized
conduction-band electrons. The anisotropic exchange interaction exists in
semiconductor structures which are not symmetric with respect to spatial
inversion, for instance in bulk zinc-blend semiconductors. The interaction has
both symmetric and antisymmetric parts with respect to permutation of spin
components. The antisymmetric (Dzyaloshinskii-Moriya) interaction is the
strongest one. It contributes significantly into spin relaxation of localized
electrons; in particular, it governs low-temperature spin relaxation in n-GaAs
with the donor concentration near 10^16cm-3. The interaction must be allowed
for in designing spintronic devices, especially spin-based quantum computers,
where it may be a major source of decoherence and errors.

</DOC>
<DOC>
<DOCNO> 40247 </DOCNO>
The Quark Distributions of Baryons


  The recent progress in the investigations on the quark structure of the
$\Lambda$ and $\Sigma$ baryons are reviewed. It is shown that the quark
structure of $\Lambda$ and $\Sigma$ hyperons can provide a new domain to test
various theories concerning the spin and flavor structure of the nucleon. The
$\Lambda$ and $\Sigma$ Physics might be new directions to explore the quark
distributions of baryons both theoretically and experimentally.

</DOC>
<DOC>
<DOCNO> 122165 </DOCNO>
Central Rotation Curves of Galaxies


  We emphasize the use of high-resolution CO line observations to derive
central rotation curves of galaxies. We present an example for high-resolution
interferometer observations of NGC 3079, and discuss the PV diagram and derived
rotation curve. The CO central rotation curves are combined with the outer
curves from \ha and HI-line observations to obtain total RC. We show that well
resolved RCs for massive galaxies generally start from non-zero velocities at
the nucleus.

</DOC>
<DOC>
<DOCNO> 8450 </DOCNO>
Spin-fermion model near the quantum critical point: one-loop


  We consider spin and electronic properties of itinerant electron systems,
described by the spin-fermion model, near the antiferromagnetic critical point.
We expand in the inverse number of hot spots in the Brillouin zone, N and
present the results beyond previously studied $N = \infty $ limit. We found two
new effects: (i) Fermi surface becomes nested at hot spots, and (ii) vertex
corrections give rise to anomalous spin dynamics and change the dynamical
critical exponent from z=2 to z>2.
  To first order in 1/N we found $z = 2N/(N-2)$ which for a physical N=8 yields
$z\approx 2.67$.

</DOC>
<DOC>
<DOCNO> 10664 </DOCNO>
Magnetic ordering and fluctuation in kagome lattice antiferromagnets, Fe


  Jarosite family compounds, KFe_3(OH)_6(SO_4)_2, (abbreviate Fe jarosite), and
KCr_3(OH)_6(SO_4)_2, (Cr jarosite), are typical examples of the Heisenberg
antiferromagnet on the kagome lattice and have been investigated by means of
magnetization and NMR experiments. The susceptibility of Cr jarosite deviates
from Curie-Weiss law due to the short-range spin correlation below about 150 K
and shows the magnetic transition at 4.2 K, while Fe jarosite has the
transition at 65 K. The susceptibility data fit well with the calculated one on
the high temperature expansion for the Heisenberg antiferromagnet on the kagome
lattice. The values of exchange interaction of Cr jarosite and Fe jarosite are
derived to be J_Cr = 4.9 K and J_Fe = 23 K, respectively. The 1H-NMR spectra of
Fe jarosite suggest that the ordered spin structure is the q = 0 type with
positive chirality of the 120 degrees configuration. The transition is caused
by a weak single-ion type anisotropy. The spin-lattice relaxation rate, 1/T_1,
of Fe jarosite in the ordered phase decreases sharply with lowering the
temperature and can be well explained by the two-magnon process of spin wave
with the anisotropy.

</DOC>
<DOC>
<DOCNO> 102651 </DOCNO>
Isomorphism of the groups of Vassiliev Invariants of Legendrian and of


  The study of the Vassiliev invariants of Legendrian knots was started by D.
Fuchs and S. Tabachnikov who showed that the groups of complex-valued Vassiliev
invariants of Legendrian and of framed knots in the standard contact $R^3$ are
canonically isomorphic.
  Recently we constructed the first examples where Vassiliev invariants of
Legendrian and of framed knots are different, and Vassiliev invariants of
Legendrian knots distinguish Legendrian knots that are isotopic as framed knots
and homotopic as Legendrian immersions. This raised the question what
information about Legendrian knots can be captured using Vassiliev invariants.
  Here we answer this question by showing that for any contact 3-manifold with
a cooriented contact structure the groups of Vassiliev invariants of Legendrian
knots and of knots that are nowhere tangent to a vector field that coorients
the contact structure are canonically isomorphic.

</DOC>
<DOC>
<DOCNO> 152074 </DOCNO>
Chern-Simons action in noncommutative space


  We derive the noncommutative Chern-Simons action induced by Dirac fermions
coupled to a background gauge field, for the fundamental, antifundamental, and
the adjoint representation. We discuss properties of the noncommutative
Chern-Simons action showing in particular that the Seiberg-Witten formula maps
it into the standard commutative Chern-Simons action.

</DOC>
<DOC>
<DOCNO> 121692 </DOCNO>
EROs and the formation epoch of field ellipticals


  A comparison is presented between the observed surface density of extremely
red objects (EROs) and the densities of red high-z elliptical galaxies
predicted by Pure Luminosity Evolution (PLE) and by some CDM hierarchical
models. The analysis is based on the widest field survey for EROs available to
date (covering in total $\sim$850 arcmin^2), and it takes into account the
effects of ERO clustering. Good agreement is found between the observed surface
densities of EROs and those predicted by PLE models for ellipticals selected
using the same color and luminosity thresholds. Since there is evidence that
the bulk of EROs are passively evolving ellipticals, this result implies that
most field ellipticals were fully assembled at least by $z\sim$2.5. Existing
hierarchical models predict instead a surface density of red ellipticals that
is much smaller than that of the EROs.

</DOC>
<DOC>
<DOCNO> 121143 </DOCNO>
Effects of weak lensing on the topology of CMB maps


  We investigate the non-Gaussian signatures in Cosmic Microwave Background
(CMB) maps induced by the intervening large-scale structure through weak
lensing. In order to measure the deviation from the Gaussian behavior of the
intrinsic temperature anisotropies, we use a family of three morphological
descriptors, the so-called Minkowski functionals. We show analytically how
these quantities depend on the temperature threshold, and compare the results
to numerical experiments including the instrumental effects of Planck.
Minkowski functionals can directly measure the statistical properties of the
displacement field and hence provide useful constraints on large-scale
structure formation in the past.

</DOC>
<DOC>
<DOCNO> 101710 </DOCNO>
The relative consistency of g<cf(Sym(omega))


  We prove the consistency result from the title. By forcing we construct a
model of g=aleph_1, b=cf(Sym(omega))=aleph_2.

</DOC>
<DOC>
<DOCNO> 83257 </DOCNO>
Exploiting Diversity in Natural Language Processing: Combining Parsers


  Three state-of-the-art statistical parsers are combined to produce more
accurate parses, as well as new bounds on achievable Treebank parsing accuracy.
Two general approaches are presented and two combination techniques are
described for each approach. Both parametric and non-parametric models are
explored. The resulting parsers surpass the best previously published
performance results for the Penn Treebank.

</DOC>
<DOC>
<DOCNO> 83133 </DOCNO>
DES: a Challenge Problem for Nonmonotonic Reasoning Systems


  The US Data Encryption Standard, DES for short, is put forward as an
interesting benchmark problem for nonmonotonic reasoning systems because (i) it
provides a set of test cases of industrial relevance which shares features of
randomly generated problems and real-world problems, (ii) the representation of
DES using normal logic programs with the stable model semantics is simple and
easy to understand, and (iii) this subclass of logic programs can be seen as an
interesting special case for many other formalizations of nonmonotonic
reasoning. In this paper we present two encodings of DES as logic programs: a
direct one out of the standard specifications and an optimized one extending
the work of Massacci and Marraro. The computational properties of the encodings
are studied by using them for DES key search with the Smodels system as the
implementation of the stable model semantics. Results indicate that the
encodings and Smodels are quite competitive: they outperform state-of-the-art
SAT-checkers working with an optimized encoding of DES into SAT and are
comparable with a SAT-checker that is customized and tuned for the optimized
SAT encoding.

</DOC>
<DOC>
<DOCNO> 117683 </DOCNO>
A direct view of the AGN powering IRAS12393+3520


  We report the first direct X-ray evidence that an AGN is hidden in the center
of IRAS12393+3520. An ASCA observation of this target unveiled a bright (0.5-10
keV luminosity 3.9 x 10^42 erg/s) and variable source, with minimum observed
doubling/halving time scale comprised in the range 30-75 ks. A model composed
by a simple power-law, with photon index ~1.8 and an absorption edge, whose
threshold energy is consistent with K-shell photoionization of OVII, provides
an adequate fit of the spectrum. This suggests that we are observing the
emission from the nuclear region through a warm absorber of N_H a few
10^{21}/cm/cm. If it has internal dust with Galactic gas-to-dust ratio, it
could explain the lack of broad Hbeta emission, even in the episodic presence
of a broad Halpha emission line. Optical spectra obtained over several years
show indeed variations in the strength of this broad Halpha component. A
distribution of dusty, optically thick matter on spatial scales a few hundreds
parsec, which does not intercept the line of sight towards the nucleus, is
probably required to account simultaneously for the relative [OIII] luminosity
deficit in comparison to the X-rays. The high IR to X-ray luminosity ratio is
most likely due to intense star formation in the circumnuclear region.
IRAS12393+3520 might thus exhibit simultaneously nuclear activity and
remarkable star formation.

</DOC>
<DOC>
<DOCNO> 70235 </DOCNO>
Scenario for Ultrarelativistic Nuclear Collisions: III. Gluons in the


  We derive expressions for various correlators of the gauge field and find the
propagators in Hamiltonian dynamics which employs a new gauge $A^\tau=0$. This
gauge is a part of the wedge form of relativistic dynamics suggested earlier as
a tool for the study of quantum dynamics in ultra-relativistic heavy ion
collisions. We prove that the gauge is completely fixed. The gauge field is
quantized and the field of radiation and the longitudinal fields are
unambiguously separated. The new gauge puts the quark and gluon fields of the
colliding hadrons in one Hilbert space and thus allows one to avoid
factorization.

</DOC>
<DOC>
<DOCNO> 151844 </DOCNO>
Abelian and center gauges in continuum Yang-Mills-Theory


  Abelian and center gauges are considered in continuum Yang-Mills theory in
order to detect the magnetic monopole and center vortex content of gauge field
configurations. Specifically we examine the Laplacian Abelian and center
gauges, which are free of Gribov copies, as well as the center gauge analog of
the (Abelian) Polyakov gauge. In particular, we study meron, instanton and
instanton-anti-instanton field configurations in these gauges and determine
their monopole and vortex content. While a single instanton does not give rise
to a center vortex, we find center vortices for merons. Furthermore we provide
evidence, that merons can be interpreted as intersection points of center
vortices. For the instanton-anti-instanton pair, we find a center vortex
enclosing their centers, which carries two monopole loops.

</DOC>
<DOC>
<DOCNO> 99403 </DOCNO>
Extender Based Radin Forcing


  We define extender sequences, generelizing measure sequences from Radin
Forcing. Using the extender sequences we combine Gitik-Magidor forcing for
adding many Prikry sequences with Radin forcing. This forcing satisfies Prikry
like condition, destroys no cardinals, and has a kind of properness. Depending
on the large cardinal we start with, this forcing can blow the power of a
cardinal together with changing its' cofinality to a prescribe value. If this
prescribed value is the cardinal itself then it remains regular and even can
remain measurable.

</DOC>
<DOC>
<DOCNO> 150623 </DOCNO>
Constraints on effective Lagrangian of D-branes from non-commutative


  It was argued that there are two different descriptions of the effective
Lagrangian of gauge fields on D-branes by non-commutative gauge theory and by
ordinary gauge theory in the presence of a constant B field background. In the
case of bosonic string theory, however, it was found in the previous works that
the two descriptions are incompatible under the field redefinition which
relates the non-commutative gauge field to the ordinary one found by Seiberg
and Witten. In this paper we resolve this puzzle to observe the necessity of
gauge-invariant but B-dependent correction terms involving metric in the field
redefinition which have not been considered before. With the problem resolved,
we establish a systematic method under the alpha' expansion to derive the
constraints on the effective Lagrangian imposed by the compatibility of the two
descriptions where the form of the field redefinition is not assumed.

</DOC>
<DOC>
<DOCNO> 101674 </DOCNO>
The modularity conjecture for rigid Calabi-Yau threefolds over Q


  We formulate the modularity conjecture for rigid Calabi-Yau threefolds
defined over the field Q of rational numbers. We establish the modularity for
the rigid Calabi-Yau threefold arising from the root lattice A_3. Our proof is
based on geometric analysis.

</DOC>
<DOC>
<DOCNO> 84791 </DOCNO>
The Kerr-Schild ansatz for the Nariai spacetime and the generating


  We will show that the Nariai metric, i.e. the static spherically symmetric
vacuum spacetime with a cosmological constant, admits a conformally Kerr-Schild
spacetime representation. We find the vacuum solutions of the Einstein-Maxwell
equations for the Nariai metric using the Horsky-Mitskievich generating
conjecture.

</DOC>
<DOC>
<DOCNO> 100670 </DOCNO>
Singular projective varieties and quantization


  By the quantization condition compact quantizable Kaehler manifolds can be
embedded into projective space. In this way they become projective varieties.
The quantum Hilbert space of the Berezin-Toeplitz quantization (and of the
geometric quantization) is the projective coordinate ring of the embedded
manifold. This allows for generalization to the case of singular varieties. The
set-up is explained in the first part of the contribution. The second part of
the contribution is of tutorial nature. Necessary notions, concepts, and
results of algebraic geometry appearing in this approach to quantization are
explained. In particular, the notions of projective varieties, embeddings,
singularities, and quotients appearing in geometric invariant theory are
recalled.

</DOC>
<DOC>
<DOCNO> 150988 </DOCNO>
Effective Quarks and Their Interactions


  This talk will summarise the progress we have made in our programme to both
characterise and construct charges in gauge theories. As an application of
these ideas we will see how the dominant glue surrounding quarks, which is
responsible for asymptotic freedom, emerges from a constituent description of
the interquark potential.

</DOC>
<DOC>
<DOCNO> 11666 </DOCNO>
Excitations of the field-induced soliton lattice in CuGeO3


  Here we report the first inelastic neutron scattering study of the magnetic
excitations in the incommensurate phase of a spin-Peierls material. The results
on CuGeO3 provide direct evidence of a finite excitation gap, two sharp
magnetic excitation branches and a very low-lying excitation which is
identified as a phason mode, the Goldstone mode of the incommensurate soliton
lattice.

</DOC>
<DOC>
<DOCNO> 119832 </DOCNO>
Constraints on Cluster Properties Using X-ray and Optical Data


  In this work we show that combining different cluster data sets is a powerful
tool to constrain both, the cosmology and cluster properties. We assume a model
with 9 parameters and fit them to 5 cluster data sets. From that fit, we
conclude that only low density universes are compatible with the previous data
and we also get some interesting conclusions on the rest of parameters.

</DOC>
<DOC>
<DOCNO> 84803 </DOCNO>
Singularities of wavefronts and lightcones in the context of GR via null


  We describe an approach to the issue of the singularities of null
hypersurfaces, due to the focusing of null geodesics, in the context of the
recently introduced formulation of GR via null foliations.

</DOC>
<DOC>
<DOCNO> 10409 </DOCNO>
Thermodynamics of a Pseudospin-Electron Model


  The purpose of this article is to present the thermodynamics of the
pseudospin-electron model in the case of the different type interactions
between pseudospins.
 First, we provide an overview of the results of works which deal with the
theoretical investigation of the pseudospin-electron model with the inclusion
of the direct pseudospin-pseudospin interaction (but without the electron
transfer).
 Second, we present the results of the investigation of the model in the case
of the absence of the direct pseudospin-pseudospin interaction and Hubbard
correlation, when interaction between pseudospins via conducting electron is
done.

</DOC>
<DOC>
<DOCNO> 99270 </DOCNO>
The HyperK\"ahler Geometry Associated to Wolf Spaces


  Let G be a compact simple Lie group and the O the minimal nilpotent orbit in
g^C. We determine all G-invariant K\"ahler potentials for hyperK\"ahler metrics
compatible with the KKS complex symplectic form on O.

</DOC>
<DOC>
<DOCNO> 122917 </DOCNO>
The ROSAT-ESO Flux-Limited X-Ray (REFLEX) Galaxy Cluster Survey III: The


  We present a measure of the power spectrum on scales from 15 to 800 Mpc/h
using the ROSAT-ESO Flux-Limited X-Ray(REFLEX) galaxy cluster catalogue. The
REFLEX survey provides a sample of the 452 X-ray brightest southern clusters of
galaxies with the nominal flux limit S=3.0 10^{-12}erg/s/cm2 for the ROSAT
energy band (0.1-2.4)keV. Several tests are performed showing no significant
incompletenesses of the REFLEX clusters with X-ray luminosities brighter than
10^{43}erg/s up to scales of about 800 Mpc/h. They also indicate that cosmic
variance might be more important than previous studies suggest. We regard this
as a warning not to draw general cosmological conclusions from cluster samples
with a size smaller than REFLEX. Power spectra, P(k), of comoving cluster
number densities are estimated for flux- and volume-limited subsamples. The
most important result is the detection of a broad maximum within the comoving
wavenumber range 0.022<k<0.030 h/Mpc. The data suggest an increase of the power
spectral amplitude with X-ray luminosity. Compared to optically selected
cluster samples the REFLEX P(k)is flatter for wavenumbers k<0.05 h/Mpc thus
shifting the maximum of P(k) to larger scales. The smooth maximum is not
consistent with the narrow peak detected at k=0.05 h/Mpc using the Abell/ACO
richness $\ge 0$ data. In the range 0.02<k<0.4 h/Mpc general agreement is found
between the slope of the REFLEX P(k) and those obtained with optically selected
galaxies. A semi-analytic description of the biased nonlinear power spectrum in
redshift space gives the best agreement for low-density Cold Dark Matter models
with or without a cosmological constant.

</DOC>
<DOC>
<DOCNO> 150410 </DOCNO>
U(1) gauge theory over discrete space-time and phase transitions


  We first apply Connes' noncommutative geometry to a finite point space. The
explicit form of the action functional of U(1) gauge field on this n-point
space is obtained. We then consider the case when the n-point space is replaced
by {space-time}\times{n-point space}. This action is shown to relate the
Hamiltonian of the continuous-spin formulation of the Potts model. We argue
that U(1) gauge theory on the discrete space-time determines the geometric
origin of a class of phase transitions.

</DOC>
<DOC>
<DOCNO> 178712 </DOCNO>
Density dependent hadron field theory for asymmetric nuclear matter and


  The density dependent relativistic hadron field (DDRH) theory is applied to
strongly asymmetric nuclear matter and finite nuclei far off stability. A new
set of in-medium meson-nucleon vertices is derived from Dirac-Brueckner
Hartree-Fock (DBHF) calculations in asymmetric matter, now accounting also for
the density dependence of isovector coupling constants. The scalar-isovector
$\delta$ meson is included. Nuclear matter calculations show that it is
necessary to introduce a momentum correction in the extraction of coupling
constants from the DBHF self-energies in order to reproduce the DBHF equation
of state by DDRH mean-field calculations. The properties of DDRH vertices
derived from the Groningen and the Bonn A nucleon-nucleon (NN) potentials are
compared in nuclear matter calculations and for finite nuclei. Relativistic
Hartree results for binding energies, charge radii, separation energies and
shell gaps for the Ni and Sn isotopic chains are presented. Using the momentum
corrected vertices an overall agreement to data on a level of a few percent is
obtained. In the accessible range of asymmetries the $\delta$ meson
contributions to the self-energies are found to be of minor importance but
asymmetry dependent fluctuations may occur.

</DOC>
<DOC>
<DOCNO> 70430 </DOCNO>
Power corrections to the process $\gamma\gamma^*\to \pi\pi$ in the


  We applied QCD Light Cone Sum Rules to estimate power corrections to the
helicity-conserving amplitude in the process $\gamma^*\gamma\to \pi\pi$. We
found that above $Q^2 \sim 4$ GeV$^2$ power corrections are numerically small
and the twist-2 part dominates.The amplitude can be reliably calculated in this
region using models of $2 \pi$ distribution amplitudes as an input. We found
that the magnitude of the NLO corrections depends rather strongly on the
normalization of the gluonic distribution amplitude.

</DOC>
<DOC>
<DOCNO> 71522 </DOCNO>
Neutrino focusing


  We study the lensing of neutrinos by astrophysical objects. At the difference
of photons, neutrinos can cross a stellar core; as a result the lens quality
improves. While Uranians alone would benefit from this effect in the Sun,
similar effects could be considered for binary systems.

</DOC>
<DOC>
<DOCNO> 12685 </DOCNO>
Power Laws are Boltzmann Laws in Disguise


  Using a model based on generalised Lotka Volterra dynamics together with some
recent results for the solution of generalised Langevin equations, we show that
the equilibrium solution for the probability distribution of wealth has two
characteristic regimes. For large values of wealth it takes the form of a
Pareto style power law. For small values of wealth, (w less then wmin) the
distribution function tends sharply to zero with infinite slope. The origin of
this law lies in the random multiplicative process built into the model. Whilst
such results have been known since the time of Gibrat, the present framework
allows for a stable power law in an arbitrary and irregular global dynamics, so
long as the market is `fair', i.e., there is no net advantage to any particular
group or individual. We show for our model that the relative distribution of
wealth follows a time independent distribution of this form even thought the
total wealth may follow a more complicated dynamics and vary with time in an
arbitrary manner. In developing the theory, we draw parallels with conventional
thermodynamics and derive for the system the associated laws of `econodynamics'
together with the associated econodynamic potentials. The power law that arises
in the distribution function may then be identified with new additional
logarithmic terms in the familiar Boltzmann distribution function for the
system. The distribution function of stock market returns for our model, it is
argued, will follow the same qualitative laws and exhibit power law behaviour.

</DOC>
<DOC>
<DOCNO> 119100 </DOCNO>
Multiple and variable X-ray sources in the globular clusters omega Cen,


  We detect stars from the Hipparcos and Tycho Catalogues in the field of view
of observations with the ROSAT HRI of three globular clusters. We use the
positions of these stars to reduce the systematic error in the positions of
X-ray sources in the clusters to ~2'' for omega Cen and NGC6752, and 1'' for
NGC6397. We detect three X-ray sources in the core of omega Cen, and four in
the core of NGC6752; the data for the center of NGC6397 may be fitted with five
or six sources. Outside the cores, but within the half-mass radius of the
clusters, we detect two sources in omega Cen, one in NGC6397 and two in
NGC6752; these may or may not be cluster members. A ROSAT HRI observation of
Liller 1 does not detect a low-luminosity source, at a limit below a detection
with ASCA. We discuss the nature of the low-luminosity X-ray sources in
globular clusters in the light of these new results.

</DOC>
<DOC>
<DOCNO> 169923 </DOCNO>
A spin-coherent semiconductor photo-detector for quantum communication


  We describe how quantum information may be transferred from photon
polarization to electron spin in a semiconductor device. The transfer of
quantum information relies on selection rules for optical transitions, such
that two superposed photon polarizations excite two superposed spin states.
Entanglement of the electron spin state with the spin state of the remaining
hole is prevented by using a single, non-degenerate initial valence band. The
degeneracy of the valence band is lifted by the combination of strain and a
static magnetic field. We give a detailed description of a semiconductor
structure that transfers photon polarization to electron spin coherently, and
allows electron spins to be stored and to be made available for quantum
information processing.

</DOC>
<DOC>
<DOCNO> 151829 </DOCNO>
Exact renormalization flow and domain walls from holography


  The holographic correspondence between 2d, N=2 quantum field theories and
classical 4d, N=2 supergravity coupled to hypermultiplet matter is proposed.
The geometrical constraints on the target space of the 4d, N=2 non-linear
sigma-models in N=2 supergravity background are interpreted as the exact
renormalization group flow equations in two dimensions. Our geometrical
description of the renormalization flow is manifestly covariant under general
reparametrization of the 2d coupling constants. An explicit exact solution to
the 2d renormalization flow, based on its dual holographic description in terms
of the Zamolodchikov metric, is considered in the particular case of the
four-dimensional NLSM target space described by the SU(2)-invariant (Weyl)
anti-self-dual Einstein metrics. The exact regular (Tod-Hitchin) solutions to
these metrics are governed by the Painlev'e VI equation, and describe domain
walls.

</DOC>
<DOC>
<DOCNO> 102364 </DOCNO>
On the mixing time of simple random walk on the super critical


  We study the robustness under perturbations of mixing times, by studying
mixing times of random walks in percolation clusters inside boxes in $\Z^d$. We
show that for $d \geq 2$ and $p > p_c(\Z^d)$, the mixing time of simple random
walk on the largest cluster inside $\{-n,...,n\}^d$ is $\Theta(n^2)$ - thus the
mixing time is robust up to constant factor.

</DOC>
<DOC>
<DOCNO> 69318 </DOCNO>
Soft SUSY Breaking, Dilaton Domination and Intermediate Scale String


  We present an analysis of the low-energy implications of an intermediate
scale ~10^{11} GeV string theory.
 We mainly focus on the evolution of the physical parameters under the
renormalisation group equations (RGEs) and find several interesting new
features that differ from the standard GUT scale or Planck scale scenarios. We
give a general discussion of soft supersymmetry breaking terms in type I
theories and then investigate the renormalization group running. In the dilaton
domination scenario, we present the sparticle spectra, analyzing constraints
from charge and colour breaking, fine tuning and radiative electroweak symmetry
breaking. We compare with the allowed regions of parameter space when the RGEs
start running at the standard GUT or the intermediate scales, and find quite
remarkably that the dilaton dominated supersymmetry breaking scenario, which is
essentially ruled out from constraints on charge and colour breaking if the
fundamental scale is close to the Planck mass, is allowed in a large region of
parameter space if the fundamental scale is intermediate.

</DOC>
<DOC>
<DOCNO> 122228 </DOCNO>
Microlensing of Quasars


  There are two possible causes of variability in gravitationally lensed
quasars: intrinsic fluctuations of the quasar and ``microlensing'' by compact
objects along the line of sight. If disentangled from each other,
microlens-induced variability can be used to study two cosmological issues of
great interest: the size and brightness profile of quasars on one hand, and the
distribution of compact (dark) matter along the line of sight on the other.
Here we present a summary of recent observational evidence for quasar
microlensing as well as of theoretical progress in the field. Particular
emphasis is given to the questions which microlensing can address regarding the
search for dark matter, both in the halos of lensing galaxies and in a
cosmologically distributed form. A discussion of desired observations and
required theoretical studies is presented as a conclusion/outlook.

</DOC>
<DOC>
<DOCNO> 101754 </DOCNO>
On asymptotic solvability of random graph's laplacians


  We observe that the Laplacian of a random graph G on N vertices represents
and explicitly solvable model in the limit of infinitely increasing N. Namely,
we derive recurrent relations for the limiting averaged moments of the
adjacency matrix of G. These relations allow one to study the corresponding
eigenvalue distribution function; we show that its density has an infinite
support in contrast to the case of the ordinary discrete Laplacian.

</DOC>
<DOC>
<DOCNO> 67650 </DOCNO>
Supernova Bounds on Majoron-emitting decays of light neutrinos


  Neutrino masses arising from the spontaneous violation of ungauged
lepton-number are accompanied by a physical Goldstone boson, generically called
Majoron. In the high-density supernova medium the effects of Majoron-emitting
neutrino decays are important even if they are suppressed in vacuo by small
neutrino masses and/or small off-diagonal couplings. We reconsider the
influence of these decays on the neutrino signal of supernovae in the light of
recent Super-Kamiokande data on solar and atmospheric neutrinos. We find that
majoron-neutrino coupling constants in the range $3\times 10^{-7}\lsim g\lsim
2\times 10^{-5}$ or $g \gsim 3 \times 10^{-4}$ are excluded by the observation
of SN1987A. Then we discuss the potential of Superkamiokande and the Sudbury
Neutrino Observatory to detect majoron neutrino interactions in the case of a
future galactic supernova. We find that these experiments could probe majoron
neutrino interactions with improved sensitivity.

</DOC>
<DOC>
<DOCNO> 40351 </DOCNO>
Energy loss of fast quarks in nuclei


  We report an analysis of the nuclear dependence of the yield of Drell-Yan
dimuons from the 800 GeV/c proton bombardment of $^2H$, C, Ca, Fe, and W
targets. Employing a new formulation of the Drell-Yan process in the rest frame
of the nucleus, this analysis examines the effect of initial-state energy loss
and shadowing on the nuclear-dependence ratios versus the incident proton's
momentum fraction and dimuon effective mass. The resulting energy loss per unit
path length is $-dE/dz = 2.32 \pm 0.52\pm 0.5$ GeV/fm. This is the first
observation of a nonzero energy loss of partons traveling in nuclear
environment.

</DOC>
<DOC>
<DOCNO> 118467 </DOCNO>
The extinction curve of the lensing galaxy of B1152+199 at z=0.44


  We present UBVRIz' photometry of the gravitational lens candidate CLASS
B1152+119 obtained with the Nordic Optical Telescope. The two QSO components
are resolved in the B, V, R, I and z' bands confirming the lensing nature of
the system. The z=0.44 lens galaxy is clearly detected in B, R, I and z' and
its position is found to be almost coincident with the faint QSO image which is
heavily extincted (relative to the brighter QSO image) by dust in the lens
galaxy. The extinction curve of the lens galaxy derived from the relative
photometry is well fitted by a Galactic extinction law with 1.3 < R_V < 2.0 and
E(B-V) ~ 1. From a simple model of the system we predict a time delay of ~ 60
days.

</DOC>
<DOC>
<DOCNO> 100776 </DOCNO>
On the fermionc formula and the Kirillov-Reshetikhin conjecture


  The fermionic formula conjectured by Kirillov and Reshetikhin describes the
decomposition (as a module for $U_q(\frak g)$) of a tensor product of multiples
of of fundamental representations $W(m\lambda_i)$ of the corresponding quantum
affine algebras. In this paper, we show that the conjecture is true for the
modules W(m\lambda_i), if $i$ is such that the corresponding simple root occurs
in the highest root of the simple Lie algebra with multiplicity at most 2. In
particular, the conjecture is established for all but a few nodes for the
exceptional algebras.

</DOC>
<DOC>
<DOCNO> 70827 </DOCNO>
Feynman's Entropy and Decoherence Mechanism


  If we reduce coherence in a given quantum system, the result is an increase
in entropy. Does this necessarily convert this quantum system into a classical
system? The answer to this question is No. The decrease of coherence means more
uncertainty. This does not seem to make the system closer to classical system
where there are no uncertainties. We examine the problem using two coupled
harmonic oscillators where we make observations on one of them while the other
oscillator is assumed to be unobservable or to be in Feynman's rest of the
universe. Our ignorance about the rest of the universe causes an increase in
entropy. However, does the system act like a classical system? The answer is
again No. When and how does this system appear like a classical system? It is
shown that this paradox can be resolved only if measurements are taken along
the normal coordinates. It is also shown that Feynman's parton picture is one
concrete physical example of this decoherence mechanism.

</DOC>
<DOC>
<DOCNO> 11046 </DOCNO>
Small world effects in evolution


  For asexual organisms point mutations correspond to local displacements in
the genotypic space, while other genotypic rearrangements represent long-range
jumps. We investigate the spreading properties of an initially homogeneous
population in a flat fitness landscape, and the equilibrium properties on a
smooth fitness landscape. We show that a small-world effect is present: even a
small fraction of quenched long-range jumps makes the results indistinguishable
from those obtained by assuming all mutations equiprobable. Moreover, we find
that the equilibrium distribution is a Boltzmann one, in which the fitness
plays the role of an energy, and mutations that of a temperature.

</DOC>
<DOC>
<DOCNO> 85538 </DOCNO>
Bursts of Radiation and Recoil Effects in Electromagnetism and


  The Maxwell field of a charge e which experiences an impulsive acceleration
or deceleration is constructed explicitly by subdividing Minkowskian space-time
into two halves bounded by a future null-cone and then glueing the halves back
together with appropriate matching conditions. The resulting retarded radiation
can be viewed as instantaneous electromagnetic bremsstrahlung. If we similarly
consider a spherically symmetric, moving gravitating mass, to experience an
impulsive deceleration, as viewed by a distant observer, then this is
accompanied by the emission of a light-like shell whose total energy measured
by this observer is the same as the kinetic energy of the source before it
stops. This phenomenon is a recoil effect which may be thought of as a limiting
case of a Kinnersley rocket.

</DOC>
<DOC>
<DOCNO> 13765 </DOCNO>
Dephasing and Metal-Insulator Transition


  The metal-insulator transition (MIT) observed in two-dimensional (2D) systems
is apparently contradictory to the well known scaling theory of localization.
By investigating the conductance of disordered one-dimensional systems with a
finite phase coherence length, we show that by changing the phase coherence
length or the localization length, it is possible to observe the transition
from insulator-like behavior to metal-like behavior, and the transition is a
crossover between the quantum and classical regimes. The resemblance between
our calculated results and the experimental findings of 2D MIT suggests that
the observed metallic phase could be the result of a finite dephasing rate.

</DOC>
<DOC>
<DOCNO> 100295 </DOCNO>
Uniqueness Results for Matrix-Valued Schr\"odinger, Jacobi, and


  Let $g(z,x)$ denote the diagonal Green's matrix of a self-adjoint $m\times m$
matrix-valued Schr\"odinger operator $H= -\f{d^2}{dx^2}I_m +Q(x)$ in $L^2
(\bbR)^{m}$, $m\in\bbN$. One of the principal results proven in this paper
states that for a fixed $x_0\in\bbR$ and all $z\in\bbC_+$, $g(z,x_0)$ and
$g^\prime (z,x_0)$ uniquely determine the matrix-valued $m\times m$ potential
$Q(x)$ for a.e.~$x\in\bbR$. We also prove the following local version of this
result. Let $g_j(z,x)$, $j=1,2$ be the diagonal Green's matrices of the
self-adjoint Schr\"odinger operators $H_j=-\f{d^2}{dx^2}I_m +Q_j(x)$ in $L^2
(\bbR)^{m}$. Suppose that for fixed $a>0$ and $x_0\in\bbR$,
$\|g_1(z,x_0)-g_2(z,x_0)\|_{\bbC^{m\times m}}+ \|g_1^\prime (z,x_0)-g_2^\prime
(z,x_0)\|_{\bbC^{m\times m}}
\underset{|z|\to\infty}{=}O\big(e^{-2\Im(z^{1/2})a}\big)$ for $z$ inside a cone
along the imaginary axis with vertex zero and opening angle less than $\pi/2$,
excluding the real axis. Then $Q_1(x)=Q_2(x)$ for a.e.~$x\in [x_0-a,x_0+a]$.
Analogous results are proved for matrix-valued Jacobi and Dirac-type operators.

</DOC>
<DOC>
<DOCNO> 151841 </DOCNO>
N=4 Supergravity with Antisymmetric Tensor in Central Charge Superspace


  A concise geometrical formulation of N=4 supergravity containing an
antisymmetric tensor gauge field is given in central charge superspace:
graviphotons are identified in the super-vielbein on the same footing as the
vierbein and the Rarita-Schwinger fields. As a consequence of superspace
soldering, Chern-Simons terms in the fieldstrength of the antisymmetric tensor
arise as an intrinsic property of superspace with central charge coordinates.

</DOC>
<DOC>
<DOCNO> 119711 </DOCNO>
Episodic lithium production by extra-mixing in red giants


  The recent discovery of low-mass red giants with enhanced atmospherical Li
abundance in galactic low-metallicity stellar clusters adds to the mysterious
phenomenon of the Li-rich giants. We propose a combined scenario for the
Li-enrichment: engulfing a giant planet (or brown dwarf) by a red giant
(external source) activates inside the giant the "7Be-mechanism" producing Li
internally. This episodical Li-production can happen at any time on the red
giant branch and is naturally followed by Li-depletion as is observed.
Limitations of our scenario are discussed as well.

</DOC>
<DOC>
<DOCNO> 122982 </DOCNO>
Warm molecular gas in nearby galaxies. Mapping of the CO(3-2) emission


  Using the Heinrich-Hertz-Telescope on Mt. Graham, Arizona, we have observed
several nearby galaxies in the CO(3-2) line. The CO(3-2) emission traces - in
contrast to lower rotational transitions - a warmer and denser component of the
molecular gas.
  We find that this emission is spatially extended in the target galaxies. The
excitation conditions seem to vary with the location of the gas within the
galaxy, and also with the overall properties of the target objects. However, a
clear correlation between the CO(3-2) emission and other quantities, such as
Hubble type or IR luminosity, is not present.

</DOC>
<DOC>
<DOCNO> 13275 </DOCNO>
Fate of the extended states in a vanishing magnetic field: the role of


  In non-interacting or weakly-interacting 2D electron systems, the energy of
the extended states increases as the perpendicular magnetic field approaches
zero: the extended states "float up" in energy, giving rise to an insulator.
However, in those 2D systems where metallic conductivity has been recently
observed in zero magnetic field, the energy of the extended states remains
constant or even decreases as B -> 0, thus allowing conduction in the limit of
zero temperature. Here we show that aligning the electrons' spins causes the
extended states to once more "float up" in energy in the vanishing
perpendicular magnetic field, as they do for non- or weakly-interacting
electrons. The difference between extended states that float up (an insulator)
or remain finite (a metal) is thus tied to the existence of the spins.

</DOC>
<DOC>
<DOCNO> 68437 </DOCNO>
Vacuum structure in QCD and Correlation functions


  We discuss here a model of QCD vacuum in terms of quark antiquark and gluon
condensates alongwith their fluctuations. The correlation functions of hadronic
currents in such a vacuum are evaluated to extract hadron properties. The
presence of fluctuations of the condensates are emphasized. The structure of
vacuum is then generalised to finite temperatures to study correlation
functions at finite temperatures. Finally, we discuss the vacuum structure at
finite densities with diquark condensates in a Nambu JonaLasinio type model.
The coupled mass gap and superconducting gap equations are solved
selfconsistently. For certain parameters of the model nontrivial solutions of
both the gap equations are obtained. The equation of state is also computed.

</DOC>
<DOC>
<DOCNO> 117092 </DOCNO>
Sonoluminescence: Nature's Smallest BlackBody


  The Spectrum of the light emitted by a sonoluminescing bubble is extremely
well fit by the spectrum of a blackbody. Furthermore the radius of emission can
be smaller than the wavelength of the light. Consequences, for theories of
sonoluminescence are discussed.

</DOC>
<DOC>
<DOCNO> 40513 </DOCNO>
Prospects for CP-violation searches in the future experiment with


  The first description of the experimental program "OKA" with RF-separated
K+/- beam at Protvino U-70 PS is presented. The parameters of the beam as well
as the potential for CP-violation searches are discussed.

</DOC>
<DOC>
<DOCNO> 116739 </DOCNO>
It is the ambiguity. (But only three generations)


  It is suggested that generations are linked to the need of calculating
curvature of space via a deformed or discrete calculus. Quantization would
limit the deformation, building three generations, and not four, as other
interpretation could imply.

</DOC>
<DOC>
<DOCNO> 178490 </DOCNO>
Level Densities by Particle-Number Reprojection Monte Carlo Methods


  A particle-number reprojection method is applied in the framework of the
shell model Monte Carlo approach to calculate level densities for a family of
nuclei using Monte Carlo sampling for a single nucleus. In particular we can
also calculate level densities of odd-even and odd-odd nuclei despite a new
sign problem introduced by the projection on an odd number of particles. The
method is applied to level densities in the iron region using the complete
$pf+g_{9/2}$-shell. The single-particle level density parameter $a$ and the
backshift parameter $\Delta$ are extracted by fitting the microscopically
calculated level densities to the backshifted Bethe formula. We find good
agreement with experimental level densities with no adjustable parameters in
the microscopic calculations. The parameter $a$ is found to vary smoothly with
mass and does not show odd-even effects. The calculated backshift parameter
$\Delta$ displays an odd-even staggering effect versus mass and is in better
agreement with the experimental data than are the empirical values.

</DOC>
<DOC>
<DOCNO> 100656 </DOCNO>
Finite conformal modules over the N=2,3,4 superconformal algebras


  In this paper we continue the study of representation theory of formal
distribution Lie superalgebras initiated in q-alg/9706030. We study finite
Verma-type conformal modules over the N=2, N=3 and the two N=4 superconformal
algebras and also find explicitly all singular vectors in these modules. From
our analysis of these modules we obtain a complete list of finite irreducible
conformal modules over the N=2, N=3 and the two N=4 superconformal algebras.

</DOC>
<DOC>
<DOCNO> 67722 </DOCNO>
Weak form factors for heavy meson decays: an update


  We calculate the form factors for weak decays of $B_{(s)}$ and $D_{(s)}$
mesons to light pseudoscalar and vector mesons. To reveal the intimate
connection between different decay modes and to be able to perform the
calculations in the full physical $q^2$-region we use a relativistic dispersion
approach based on the constituent quark picture. This approach gives the form
factors as relativistic double spectral representations in terms of the wave
functions of the initial and final mesons. The form factors have the correct
analytic properties and satisfy general requirements of nonperturbative QCD in
the heavy quark limit.
  The disadvantages of quark models related to ill-defined effective quark
masses and not precisely known meson wave functions are reduced by fitting the
quark model parameters to lattice QCD results for the $B\to \rho$ transition
form factors at large momentum transfers and to the measured total $D\to
(K,K^*)l\nu$ decay rates. This allows us to predict numerous form factors for
all kinematically accessible $q^2$ values.

</DOC>
<DOC>
<DOCNO> 151316 </DOCNO>
Kaluza-Kelin Higher Derivative Gravity and Friedmann-Robertson-Walker


  Kaluza-Klein approach in an N(=1+3+D)-dimensional Friedmann-Robertson-Walker
type space is often adopted in the literature. We derive a compact expression
for the Friedmann equation in a (1+3+D)-dimensional space. The redundancy of
the associated field equations due to the Bianchi identity is analyzed. We also
study the dilaton gravity theory with higher-derivative gravitational
couplings. It turns out that higher-order terms will not affect the Friedmann
equation in a constant flat internal space. This is true only for the flat-De
Sitter external space. The inflationary solution in an induced-gravity model is
also discussed as an application.

</DOC>
<DOC>
<DOCNO> 13987 </DOCNO>
Phase behaviour of a hard sphere colloidal system in the presence of an


  We study the phase behaviour of a two-dimensionally confined hard sphere
colloidal system in the presence of a periodic light field of two interfering
laser beams using Monte Carlo simulations. For a given packing fraction of the
particles, the colloidal system undergoes a transition from a modulated liquid
to a modulated crystal as the light intensity is increased, corresponding to
laser induced freezing. For certain packing fractions of the colloidal
particles, the system again becomes a modulated liquid as the field strength
crosses a threshold value, showing a re-entrant behaviour.

</DOC>
<DOC>
<DOCNO> 8632 </DOCNO>
Dynamics of Excited Electrons in Copper: Role of Auger Electrons


  Within a theoretical model based on the Boltzmann equation, we analyze in
detail the structure of the unusual peak recently observed in the relaxation
time in Cu. In particular, we discuss the role of Auger electrons in the
electron dynamics and its dependence on the d-hole lifetime, the optical
transition matrix elements and the laser pulse duration. We find that the Auger
contribution to the distribution is very sensitive to both the d-hole lifetime
tau_h and the laser pulse duration tau_l and can be expressed as a monotonic
function of tau_l/tau_h. We have found that for a given tau_h, the Auger
contribution is significantly smaller for a short pulse duration than for a
longer one. We show that the relaxation time at the peak depends linearly on
the d-hole lifetime, but interestingly not on the amount of Auger electrons
generated. We provide a simple expression for the relaxation time of excited
electrons which shows that its shape can be understood by a phase space
argument and its amplitude is governed by the d-hole lifetime. We also find
that the height of the peak depends on both the ratio of the optical transition
matrix elements R=|M_{d \to sp}|^2/|M_{sp \to sp}|^2 and the laser pulse
duration. Assuming a reasonable value for the ratio, namely R = 2, and a d-hole
lifetime of tau_h=35 fs, we obtain for the calculated height of the peak Delta
tau_{th}=14 fs, in fair agreement with Delta tau_{exp} \approx 17 fs measured
for polycrystalline Cu.

</DOC>
<DOC>
<DOCNO> 120391 </DOCNO>
Signatures of exosolar planets in dust debris disks


  We apply our recently elaborated, powerful numerical approach to the
high-resolution modeling of the structure and emission of circumstellar dust
disks, incorporating all relevant physical processes. Specifically, we examine
the resonant structure of a dusty disk induced by the presence of one planet.
It is shown that the planet, via resonances and gravitational scattering,
produces (1) an asymmetric resonant dust belt with one or more clumps
intermittent with one or a few off-center cavities; and (2) a central cavity
void of dust. These features can serve as indicators of a planet embedded in
the circumstellar dust disk and, moreover, can be used to determine its major
orbital parameters and even the mass of the planet. The results of our study
reveal a remarkable similarity with various types of highly asymmetric
circumstellar disks observed with the James Clerk Maxwell Telescope around
Epsilon Eridani and Vega. The proposed interpretation of the clumps in those
disks as being resonant patterns is testable -- it predicts the asymmetric
design around the star to revolve, viz., by 1.2--1.6 deg/yr about Vega and
0.6--0.8 deg/yr about Epsilon Eri.

</DOC>
<DOC>
<DOCNO> 151465 </DOCNO>
On the Hopf algebraic origin of Wick normal-ordering


  A combinatorial formula of G.-C. Rota and J.A. Stein is taken to perform Wick
re-ordering in quantum field theory. Wick's theorem becomes a Hopf algebraic
identity called Cliffordization. The combinatorial method relying on Hopf
algebras is highly efficient in computations and yields closed algebraic
expressions.
  AMS Subject Classifications 2000: 81R50; 16W30

</DOC>
<DOC>
<DOCNO> 100087 </DOCNO>
Characterizations of ${\mathbb P}^n$ in arbitrary characteristic


  We prove that a smooth projective variety of dimension n is isomorphic to
projective n-space iff the canonical class is -(n+1)-times an ample divisor. In
characteristic zero this was proved by Kobayashi-Ochiai. We also extend the
second adjunction theorem of Ionescu and Fujita to arbitrary characteristic.

</DOC>
<DOC>
<DOCNO> 152070 </DOCNO>
Exact Renormalization Group in Algebraic Noncovariant Gauges


  I study a class of Wilsonian formulations of non-Abelian gauge theories in
algebraic noncovariant gauges where the Wilsonian infrared cutoff $\Lambda$ is
inserted as a mass term for the propagating fields. In this way the
Ward-Takahashi identities are preserved to all scales. Nevertheless the
BRS-invariance in broken and the theory is gauge-dependent and unphysical at
$\Lambda\neq0$. Then I discuss the infrared limit $\Lambda\to0$. I show that
the singularities of the axial gauge choice are avoided in planar gauge and in
light-cone gauge. Finally the rectangular Wilson loop of size $2L\times 2T$ is
evaluated at lowest order in perturbation theory and a noncommutativity between
the limits $\Lambda\to0$ and $T\to\infty$ is pointed out.

</DOC>
<DOC>
<DOCNO> 119062 </DOCNO>
The Missing Link: Early Methane ("T") Dwarfs in the Sloan Digital Sky


  We report the discovery of three cool brown dwarfs which fall in the
effective temperature gap between the latest L dwarfs currently known, with no
methane absorption bands in the 1-2.5um range, and the previously known methane
(T) dwarfs, whose spectra are dominated by methane and water. The newly
discovered objects were detected as very red objects in the Sloan Digital Sky
Survey imaging data and have JHK colors between the red L dwarfs and the blue
Gl229B-like T dwarfs. They show both CO and methane absorption in their
near-infrared spectra in addition to water, with weaker methane absorption
features in the H and K bands than those in all other methane dwarfs reported
to date. Due to the presence of methane in these bands, we propose that these
objects are early T dwarfs. The three form part of the brown dwarf spectral
sequence and fill in the large gap in the overall spectral sequence from the
hottest main sequence stars to the coolest methane dwarfs currently known.

</DOC>
<DOC>
<DOCNO> 68355 </DOCNO>
Nucleus-nucleus scattering in perturbative QCD with $N_c\to\infty$


  In the perturbative QCD with $N_c\to\infty$ equations for the amplitude of
the nucleus-nucleus scattering are derived by the effective field method. The
asymptotic form of the solution is discussed. It is argued that in the
high-energy limit the total nucleus-nucleus cross-sections become constant and
purely geometrical.

</DOC>
<DOC>
<DOCNO> 122606 </DOCNO>
The DEEP Groth Strip Survey X: Number Density and Luminosity Function of


  We present the luminosity function and color-redshift relation of a
magnitude-limited sample of 145 mostly red field E/S0 galaxies at z < 1 from
the DEEP Groth Strip Survey (GSS). Most of the E/S0s (86%) form a red envelope
in the redshift-color diagram, consistent with predictions of spectral
synthesis models in which the dominant stellar population is formed at
redshifts z > 1.5. Constructing a luminosity function of the full sample of
 145 E/S0s, we find that there is about 1.1--1.9 magnitude brightening in
rest-frame B band luminosity back to z = 0.8 from z=0, consistent with other
studies.
  Together with the red colors, this brightening favors models in which the
bulk of stars in red field E/S0s formed before z_{for} > 1.5 and have been
evolving rather quiescently with few large starbursts since then.
  Evolution in the number density of field E/S0 galaxies is harder to measure,
and uncertainties in the raw counts and their ratio to local samples might
amount to as much as a factor of two.
  Within that uncertainty, the number density of red E/S0s to z = 0.8 seems
relatively static, being comparable to or perhaps moderately less than that of
local E/S0s depending on the assumed cosmology. A doubling of E/S0 number
density since z = 1 can be ruled out with high confidence (97%) if
\Omega_{m}=1.
 Taken together, our results are consistent with the hypothesis that the
majority of luminous field E/S0s were already in place by z = 1, that the bulk
of their stars were already fairly old, and that their number density has not
changed by large amounts since then.

</DOC>
<DOC>
<DOCNO> 178620 </DOCNO>
Kinetic energy and spin-orbit splitting in nuclei near neutron drip line


  Two important ingredients of nuclear shell-structure, kinetic energy and
spin-orbit splitting, are studied as a function of orbital angular momenta \ell
and binding energies, when binding energies of neutrons decrease towards zero.
If we use the standard parameters of the Woods-Saxon potential in \beta stable
nuclei and approach the limit of zero binding energy from 10 MeV, the
spin-orbit splitting for n=1 orbitals decreases considerably for \ell=1, while
for \ell > 2 little decreasing is observed in the limit. In contrast, the
kinetic energy decreases considerably for \ell \simleq 3. The smaller the \ell
values of orbitals, the larger the decreasing rate of both kinetic energy and
spin-orbit splitting. The dependence of the above bservation on the diffuseness
of potentials is studied.

</DOC>
<DOC>
<DOCNO> 150952 </DOCNO>
Classical solutions of the Gravitating Abelian Higgs Model


  We consider the classical equations of the gravitating Abelian-Higgs model in
an axially symmetric ansatz. More properties of the solutions of these
equations (the Melvin and the sting branches) are presented. These solutions
are also constructed for winding numbers N=2. It is shown that these vortices
exist in attractive and repulsive phases, separated by the value of the Higgs
coupling constant parameter leading to self-dual equations.

</DOC>
<DOC>
<DOCNO> 85229 </DOCNO>
Exact metric around a wiggly cosmic string


  The exact metric around a wiggly cosmic string is found by modifying the
energy momentum-tensor of a straight infinitely thin cosmic string to include
an electric current along the symmetry axis.

</DOC>
<DOC>
<DOCNO> 178733 </DOCNO>
Extraction of electromagnetic neutron form factors through inclusive and


  Inclusive 3He(e,e') and exclusive 3He(e,e'n) processes with polarized
electrons and 3He have been theoretically analyzed and values for the magnetic
and electric neutron form factors have been extracted. In both cases the form
factor values agree well with the ones extracted from processes on the
deuteron. Our results are based on Faddeev solutions, modern NN forces and
partially on the incorporation of mesonic exchange currents.

</DOC>
<DOC>
<DOCNO> 70146 </DOCNO>
Strangeness enhancement from strong color fields at RHIC


  In ultra-relativistic heavy ion collisions, early stage multiple scatterings
may lead to an increase of the color electric field strength. Consequently,
particle production - especially heavy quark (and di-quark) production - is
greatly enhanced according to the Schwinger mechanism. We test this idea via
the Ultra-relativistic Quantum Molecular Dynamics model (UrQMD) for Au+Au
collisions at the full RHIC energy ($\sqrt{s} = 200$ AGeV). Relative to p+p
collisions, a factor of 60, 20 and 7 enhancement respectively, for $\Omega$
($sss$), $\Xi$ ($ss$), and $\Lambda$, $\Sigma$ ($s$) is predicted for a model
with increased color electric field strength.

</DOC>
<DOC>
<DOCNO> 71213 </DOCNO>
Fermion Masses, Mixings and Proton Decay in a Randall-Sundrum Model


  We consider a Randall-Sundrum model in which the Standard Model fermions and
gauge bosons correspond to bulk fields. We show how the observed charged
fermion masses and CKM mixings can be explained, without introducing
hierarchical Yukawa couplings. We then study the impact on the mass scales
associated with non-renormalizable operators responsible for proton decay,
neutrino masses, and flavor changing neutral currents. Although mass scales as
high as 10^{11}- 10^{12} GeV are in principle possible, dimensionless couplings
of order 10^{-8} are still needed to adequately suppress proton decay. Large
neutrino mixings seem to require new physics beyond the Standard Model.

</DOC>
<DOC>
<DOCNO> 8548 </DOCNO>
Luttinger liquids with boundaries: Power-laws and energy scales


  We present a study of the one-particle spectral properties for a variety of
models of Luttinger liquids with open boundaries. We first consider the
Tomonaga-Luttinger model using bosonization. For weak interactions the boundary
exponent of the power-law suppression of the spectral weight close to the
chemical potential is dominated by a term linear in the interaction. This
motivates us to study the spectral properties also within the Hartree-Fock
approximation. It already gives power-law behavior and qualitative agreement
with the exact spectral function. For the lattice model of spinless fermions
and the Hubbard model we present numerically exact results obtained using the
density-matrix renormalization-group algorithm. We show that many aspects of
the behavior of the spectral function close to the boundary can again be
understood within the Hartree-Fock approximation. For the repulsive Hubbard
model with interaction U the spectral weight is enhanced in a large energy
range around the chemical potential. At smaller energies a power-law
suppression, as predicted by bosonization, sets in. We present an analytical
discussion of the crossover and show that for small U it occurs at energies
exponentially (in -1/U) close to the chemical potential, i.e. that bosonization
only holds on exponentially small energy scales. We show that such a crossover
can also be found in other models.

</DOC>
<DOC>
<DOCNO> 120291 </DOCNO>
A Morphological Diagnostic for Dynamical Evolution of Wolf-Rayet Bubbles


  We have observed H-alpha and [OIII] emission from eight of the most well
defined Wolf-Rayet ring nebulae in the Galaxy. We find that in many cases the
outermost edge of the [OIII] emission leads the H-alpha emission. We suggest
that these offsets, when present, are due to the shock from the Wolf-Rayet
bubble expanding into the circumstellar envelope. Thus, the details of the WR
bubble morphology at H-alpha and [OIII] can then be used to better understand
the physical condition and evolutionary stage of the nebulae around Wolf-Rayet
stars, as well as place constraints on the nature of the stellar progenitor and
its mass loss history.

</DOC>
<DOC>
<DOCNO> 11266 </DOCNO>
Dynamics of a Vortex in a Trapped Bose-Einstein Condensate


  We consider a large condensate in a rotating anisotropic harmonic trap. Using
the method of matched asymptotic expansions, we derive the velocity of an
element of vortex line as a function of the local gradient of the trap
potential, the line curvature and the angular velocity of the trap rotation.
This velocity yields small-amplitude normal modes of the vortex for 2D and 3D
condensates. For an axisymmetric trap, the motion of the vortex line is a
superposition of plane-polarized standing-wave modes. In a 2D condensate, the
planar normal modes are degenerate, and their superposition can result in
helical traveling waves, which differs from a 3D condensate. Including the
effects of trap rotation allows us to find the angular velocity that makes the
vortex locally stable. For a cigar-shape condensate, the vortex curvature makes
a significant contribution to the frequency of the lowest unstable normal mode;
furthermore, additional modes with negative frequencies appear. As a result, it
is considerably more difficult to stabilize a central vortex in a cigar-shape
condensate than in a disc-shape one. Normal modes with imaginary frequencies
can occur for a nonaxisymmetric condensate (in both 2D and 3D). In connection
with recent JILA experiments, we consider the motion of a straight vortex line
in a slightly nonspherical condensate. The vortex line changes its orientation
in space at the rate proportional to the degree of trap anisotropy and can
exhibit periodic recurrences.

</DOC>
<DOC>
<DOCNO> 72218 </DOCNO>
Angle Dependence of Polarization Observables by Fragmentation of


  The fragmentation of deuterons into pions with nonzero angle emitted in the
kinematical region forbidden for free nucleon-nucleon collisions is analyzed.
The inclusive relativistic invariant spectrum of pions and the tensor analyzing
power ${\rm A}_{YY}$ are investigated within the framework of an impulse
approximation using different kinds of the deuteron wave function. The
influence of ${\rm P}$-wave contribution to the deuteron wave function is
studied, too. Our results are compared with the experimental data and other
calculations performed within both the non-relativistic and relativistic
approaches. It was found that theoretical calculations based on IA do not
provide a consistent understanding of the new data in a whole cumulative region
that can be caused by a influence of non-nucleon degrees of freedom.

</DOC>
<DOC>
<DOCNO> 83157 </DOCNO>
Statistics and implementation of APRNGs


  This paper has been temporarily withdrawn by the author(s),

</DOC>
<DOC>
<DOCNO> 11970 </DOCNO>
Gravity-induced Wannier-Stark ladder in an optical lattice


  We discuss the dynamics of ultracold atoms in an optical potential
accelerated by gravity. The positions and widths of the Wannier-Stark ladder of
resonances are obtained as metastable states. The metastable Wannier-Bloch
states oscillate in a single band with the Bloch period. The width of the
resonance gives the rate transition to the continuum.

</DOC>
<DOC>
<DOCNO> 71854 </DOCNO>
Skewed parton distributions and wide-angle exclusive scattering


  The overlap representation of skewed parton distributions is discussed and
applications to wide-angle Compton scattering and electroproduction of mesons
are presented. The amplitudes for these processes factorise into parton-level
subprocess amplitudes and form factors representing 1/x-moments of skewed
parton distributions.

</DOC>
<DOC>
<DOCNO> 40104 </DOCNO>
A Search for Excited Fermions at HERA


  A search for excited fermions f^* of the first generation in e^+p scattering
at the collider HERA is presented using H1 data with an integrated luminosity
of 37 pb^(-1). All electroweak decays of excited fermions, f^* -> f gamma, f W,
f Z are considered and all possible final states resulting from the Z or W
hadronic decays or decays into leptons of the first two generations are taken
into account. No evidence for f^* production is found. Mass dependent exclusion
limits on cross-sections and on the ratio of coupling constants to the
compositeness scale are derived.

</DOC>
<DOC>
<DOCNO> 71600 </DOCNO>
NEXTCALIBUR - A four-fermion generator for electron-positron collisions


  A fully massive Monte Carlo program to compute all four-fermion processes in
electron positron collisions, including Higgs boson production, is presented.
Leading higher order effects are discussed and included.

</DOC>
<DOC>
<DOCNO> 170023 </DOCNO>
Quantum algorithm for distributed clock synchronization


  The clock synchronization problem is to determine the time difference
$\Delta$ between two spatially separated clocks. When message delivery times
between the two clocks are uncertain, $O(2^{2n})$ classical messages must be
exchanged between the clocks to determine $n$ digits of $\Delta$. On the other
hand, as we show, there exists a quantum algorithm to obtain $n$ digits of
$\Delta$ while communicating only O(n) quantum messages.

</DOC>
<DOC>
<DOCNO> 11208 </DOCNO>
1/f Noise in a Coulomb Glass


  At low temperatures electron hopping in a three dimensional Coulomb glass
produces fluctuations in the single particle density of states and hence in the
resistivity. This results in a low frequency resisitivity noise spectrum which
goes as (1/f)^(alpha) where alpha is very close to 1. This holds down to
extremely low frequencies.

</DOC>
<DOC>
<DOCNO> 117097 </DOCNO>
Two exact derivations of the mass/energy relationship, E=mc^2


  The E=mc^2 relationship is not unique to special relativity. Einstein
published one exact derivation from special relativity and two approximate
derivations that used general extensions to Newtonian mechanics, and an exact
derivation is also possible if we use a "first-order" Doppler equation instead
of special relativity's "relativistic Doppler" formula. We present two sample
derivations based on different non-transverse Doppler relationships, and
briefly look at the two diverging systems of physics that result.

</DOC>
<DOC>
<DOCNO> 11664 </DOCNO>
First principles elastic constants and electronic structure of


  We have carried out a first principles study of the elastic properties and
electronic structure for two room-temperature stable Pt silicide phases,
tetragonal alpha-Pt_2Si and orthorhombic PtSi. We have calculated all of the
equilibrium structural parameters for both phases: the a and c lattice
constants for alpha-Pt_2Si and the a, b, and c lattice constants and four
internal structural parameters for PtSi. These results agree closely with
experimental data. We have also calculated the zero-pressure elastic constants,
confirming prior results for pure Pt and Si and predicting values for the six
(nine) independent, non-zero elastic constants of alpha-Pt_2Si (PtSi). These
calculations include a full treatment of all relevant internal displacements
induced by the elastic strains, including an explicit determination of the
dimensionless internal displacement parameters for the three strains in
alpha-Pt_2Si for which they are non-zero. We have analyzed the trends in the
calculated elastic constants, both within a given material as well as between
the two silicides and the pure Pt and Si phases. The calculated electronic
structure confirms that the two silicides are poor metals with a low density of
states at the Fermi level, and consequently we expect that the Drude component
of the optical absorption will be much smaller than in good metals such as pure
Pt. This observation, combined with the topology found in the first principles
spin-orbit split band structure, suggests that it may be important to include
the interband contribution to the optical absorption, even in the infrared
region.

</DOC>
<DOC>
<DOCNO> 119256 </DOCNO>
Implications of a possible 23 day periodicity for binary black hole


  We investigate the implications of a massive binary system in the centre of
the gamma-ray blazar Mkn~501 and show that the periodical behaviour recently
observed in the TeV and X-ray lightcurves may possibly be related to the
orbital motion of the relativistic jet emerging from the less massive black
hole. For the special relativistic jet properties inferred from emission
models, we derive an intrinsic orbital period of $(6-14)$ yrs and a
centre-of-mass distance of $(2.0-3.5) \times 10^{16}$ cm. If the binary is very
close with a separation of the order of that for which gravitational radiation
becomes dominant, we find a maximum primary mass of $\sim 10^8 M_{\sun}$ and a
corresponding secondary mass in the range of $\sim (4-42)\times 10^6 M_{\sun}$
depending on the intrinsic jet properties. Such values are in line with the
black hole masses expected from merger scenarios.

</DOC>
<DOC>
<DOCNO> 170715 </DOCNO>
Comment on the Possibility of a Geometric Constraint in the Schroedinger


  It is shown that the geometric constraint advocated in [R. S. Kaushal, Mod.
Phys. Lett. A 15 (2000) 1391] is trivially satisfied. Therefore, such a
constraint does not exist. We also point out another flaw in Kaushal's paper.

</DOC>
<DOC>
<DOCNO> 102321 </DOCNO>
Gromov-Hausdorff Distance for Quantum Metric Spaces


  By a quantum metric space we mean a C^*-algebra (or more generally an
order-unit space) equipped with a generalization of the Lipschitz seminorm on
functions which is defined by an ordinary metric. We develop for compact
quantum metric spaces a version of Gromov-Hausdorff distance. We show that the
basic theorems of the classical theory have natural quantum analogues. Our main
example involves the quantum tori, $A_{\th}$. We show, for consistently defined
``metrics'', that if a sequence $\{\th_n\}$ of parameters converges to a
parameter $\th$, then the sequence $\{A_{\th_n}\}$ of quantum tori converges in
quantum Gromov-Hausdorff distance to $A_{\th}$.

</DOC>
<DOC>
<DOCNO> 69537 </DOCNO>
Neutrino Masses and Leptogenesis


  I discuss the connection between neutrino masses and leptogenesis. I use
three prime examples: (1) canonical seesaw, (2) triplet Higgs, and (3) $R$
parity violation.

</DOC>
<DOC>
<DOCNO> 68633 </DOCNO>
Chaos in Superstring Cosmology


  It is shown that the general solution near a spacelike singularity of the
Einstein-dilaton-p-form field equations relevant to superstring theories and
M-theory exhibits an oscillatory behaviour of the
Belinskii-Khalatnikov-Lifshitz type. String dualities play a significant role
in the analysis.

</DOC>
<DOC>
<DOCNO> 9951 </DOCNO>
Direct measurement of polaron binding energy in AMnO$_{3}$ as a function


  Photoinduced IR absorption was measured in undoped (LaMn)_{1-\delta}O_{3} and
(NdMn)_{1-\delta}O_{3}. We observe broadening and a ~44% increase of the
midinfrared anti-Jahn-Teller polaron peak energy when La^{3+} is replaced with
smaller Nd^{3+}. The absence of any concurent large frequency shifts of the
observed PI phonon bleaching peaks and the Brillouin-zone-center internal
perovskite phonon modes measured by Raman and infrared spectroscopy indicate
that the polaron peak energy shift is mainly a consequence of an increase of
the electron phonon coupling constant with decreasing ionic radius <r_{A}> on
the perovskite A site. This indicates that the dynamical lattice effects
strongly contribute to the electronic band narrowing with decreasing <r_{A}> in
doped giant magnetoresistance manganites.

</DOC>
<DOC>
<DOCNO> 101331 </DOCNO>
Matrix representation of the generalized Moyal algebra


  It is shown that the isomorphism between the generalized Moyal algebra and
the matrix algebra follows in a natural manner from the generalized Weyl
quantization rule and from the well known matrix representation of the
destruction and creation operators.

</DOC>
<DOC>
<DOCNO> 121633 </DOCNO>
Eccentric orbits and QPOs in neutron star X-ray binaries


  We investigate the suggestion that the frequencies of the kilohertz and other
QPOs in the emission from neutron stars in low-mass X-ray binaries are
generated by geodesic motion of gas clumps around the star. First we assume,
following previous work, that the dominant frequencies produced by such motions
are the azimuthal frequency \nuk, the apsidal precession frequency \nuap, and
the first overtone of the nodal precession frequency \nunp. We investigate
whether geodesics can be found for which these frequencies agree with the
observed frequencies. Correcting calculational errors made when the geodesic
precession hypothesis was first proposed, we find that \nuk and \nuap disagree
qualitatively with the frequencies of the kilohertz QPOs for infinitesimally or
even moderately eccentric geodesics. These frequencies are similar to the
frequencies of the kilohertz QPOs only for highly eccentric geodesics, with
apastron to periastron ratios \sim3--4; for these geodesics, 2\nunp differs
qualitatively from the frequencies of the low-frequency QPOs. Next we
investigate whether these frequencies would be the dominant frequencies
produced by orbiting clumps. We find that they are not and that the dominant
frequencies are instead harmonics and sidebands of the radial epicyclic
frequency \nur. Finally, we show that gas dynamical constraints restrict the
radii of orbiting clumps to be \ll 10^{-3} of the stellar radius; the
fractional modulation that could be produced by clumps is therefore \ll
10^{-6}. We conclude that there are significant difficulties in interpreting
the kilohertz and low-frequency QPOs as consequences of geodesic motion of gas
clumps.

</DOC>
<DOC>
<DOCNO> 150857 </DOCNO>
Poincare Anomaly in Planar Field Theory


  We show the presence of Poincare anomaly in Maxwell-Chern-Simons theory with
an explicit mass term, in 2+1-dimensions.

</DOC>
<DOC>
<DOCNO> 12488 </DOCNO>
The Fractal Properties of Internet


  In this paper we show that the Internet web, from a user's perspective,
manifests robust scaling properties of the type $P(n)\propto n^{-\tau}$ where n
is the size of the basin connected to a given point, $P$ represents the density
of probability of finding n points downhill and $\tau=1.9 \pm 0.1$ s a
characteristic universal exponent. This scale-free structure is a result of the
spontaneous growth of the web, but is not necessarily the optimal one for
efficient transport. We introduce an appropriate figure of merit and suggest
that a planning of few big links, acting as information highways, may
noticeably increase the efficiency of the net without affecting its robustness.

</DOC>
<DOC>
<DOCNO> 8853 </DOCNO>
Cu-O network dependent core-hole screening in low-dimensional cuprates:


  We analyze the influence of the dimensionality on the Cu 2p_3/2 core level
X-ray photoemission spectra of undoped cuprates. Both exchange splitting and
delocalization properties are described within one framework using a multi-band
Hubbard model. The spectral intensity is calculated by means of the
Mori-Zwanzig projection technique for a CuO_4 plaquette ('zero'-dimensional),
an infinite CuO_3 chain (one-dimensional), and an infinite CuO_2 plane
(two-dimensional). The results are compared to the spectra of Bi_2CuO_4,
Sr_2CuO_3, and Sr_2CuO_2Cl_2. Our analysis allows to distinguish between
effects of the Cu-O geometry and effects from material-specific properties.

</DOC>
<DOC>
<DOCNO> 120416 </DOCNO>
Decreasing Density Gradients in Circumnuclear HII Regions of Barred


  A re-analysis of the radio continuum emission from circumnuclear regions of
the barred galaxies NGC 1022, 1326 & 4314 is presented. The spatial
distributions of Halpha and radio continuum are similar and suggest the
existence of several giant HII regions in the circumnuclear zone. The spectral
indices of the HII regions, obtained with similar angular resolution and at
three different wavelengths, indicate that in all three galaxies, the spectral
index, alpha^6_2 >-0.1. This result suggests the existence of giant HII regions
with decreasing density gradients. The average density stratifications of these
HII regions could be approximated by power-laws of the form n_e~r^-w, with
exponents in the range 1.6 < w < 2.4.

</DOC>
<DOC>
<DOCNO> 9630 </DOCNO>
Nonmonotonic Temperature Dependence of the Thermal Hall Angle of a


  We have performed high-resolution measurements of the magnetic field (0~T~$
\le B \le 9~$T) and temperature (10 K~$\le T < 140~$K) dependence of the
longitudinal and transverse Hall thermal conductivity of a twinned
YBa$_{2}$Cu$_{3}$O$_{6.95}$ single crystal. We have used and compared two
recently published methods to extract the thermal Hall angle $\theta_H(T,B)$.
Our results indicate that $\cot(\theta_H)$ varies quite accurately as $T^4$ in
the intermediate temperature range $\sim 0.3 < T/T_c$. It shows a well defined
minimum at $T_m \simeq 20~$K which resembles that observed in the $c$-axis
microwave conductivity. The electronic part of the longitudinal and the
transverse thermal conductivity show the scaling behavior for transport
properties predicted for d-wave superconductors in the temperature range $\sim
18~$K~$\le T \le 30~$K.

</DOC>
<DOC>
<DOCNO> 99730 </DOCNO>
An Index of an Equivariant Vector Field and Addition Theorems for


  The theory of indices of Morse--Bott vector fields on a manifold is
constructed and the famous localization problem for the transfer map is solved
on its base in the present paper. As a consequence, we obtained addition
theorems for the universal Pontrjagin characteristic classes in cobordisms.
These results gave us a possibility to complete the construction, which was
begun more than twenty years ago, of the universal characteristic classes'
theory.

</DOC>
<DOC>
<DOCNO> 122625 </DOCNO>
New class of low frequency QPOs: signature of nuclear burning or


  We report the discovery of a new class of low frequency quasi--periodic
variations of the X-ray flux in the X-ray bursters 4U1608-52 and 4U1636-536. We
also report an occasional detection of a similar QPO in Aql X-1. The QPOs,
associated with flux variations at the level of percents, are observed at a
frequency of 7-9 mHz. While usually the relative amplitude of flux variations
increases with energy, the newly discovered QPOs are limited to the softest
energies (1-5 keV). The observations of 4U1608-52 suggest that these QPOs are
present only when the source X-ray luminosity is within a rather narrow range
and they disappear after X-ray bursts. Approximately at the same level of the
source luminosity, type I X-ray bursts cease to exist.
  Judging from this complex of properties, we speculate that a special mode of
nuclear burning at the neutron star surface is responsible for the observed
flux variations. Alternatively, some instabilities in the accretion disk may be
responsible for these QPOs.

</DOC>
<DOC>
<DOCNO> 122560 </DOCNO>
Observations of the BL Lacertae Object OJ 287 in 1997 April and Nov


  X-ray properties of the BL Lacertae object OJ 287, observed with ASCA on 1997
April 26 and November 17, are reported. The 0.5 -- 10 keV flux was lower than
those obtained in previous X-ray observations, and no evidence of intensity
variations was found during each observation. The obtained flux densities at 1
keV, 0.22~0.26 uJy, exceed the extrapolations from lower frequency synchrotron
continua, which were measured in nearly the same period as the present ASCA
observations. The X-ray spectra acquired with the GIS and SIS were consistently
described with a single power law model modified with the Galactic absorption,
and the derived photon indices, 1.5 ~ 1.6, are flatter than those observed so
far. These results strongly suggest that the X-ray spectra observed in 1997
arise via inverse Compton process alone. The X-ray spectra obtained in 1994
(Idesawa et al 1997), exhibiting a steeper slope than those in 1997, is thought
to be contaminated by "synchrotron soft tail".

</DOC>
<DOC>
<DOCNO> 169750 </DOCNO>
Finite temperature excitations of an inhomogneous trapped Bose gas with


  We derive and discuss the temperature dependance of the condensate and
noncondensate density profile of a Bose-Einstein condensate gas with Feshbach
resonance in a parabolic trap. These quantities are calculated
self-consistently using the generalized Hartree-Fock-Bogoliubov (HFB) equations
within the Bogoliubov approximation. At zero temperature, the HFB equation can
be solved by means of a variation method that give the low excitation spectrum.
Moreover, within the two-body collision theory, we estimate the relationship
between the atom number and the external magnetic field $B$, it is in good
agreement with the data in recent experiments.

</DOC>
<DOC>
<DOCNO> 11065 </DOCNO>
Irrelevant Interactions without Composite Operators - A Remark on the


  We study the critical behaviour of symmetric $\phi^4_4$ theory including
irrelevant terms of the form $\phi^{4+2n}/\Lambda_0^{2n}$ in the bare action,
where $\Lambda_0$ is the UV cutoff (corresponding e.g. to the inverse lattice
spacing for a spin system). The main technical tool is renormalization theory
based on the flow equations of the renormalization group which permits to
establish the required convergence statements in generality and rigour. As a
consequence the effect of irrelevant terms on the critical behaviour may be
studied to any order without using renormalization theory for composite
operators. This is a technical simplification and seems preferable from the
physical point of view. In this short note we restrict for simplicity to the
symmetry class of the Ising model, i.e. one component $\phi^4_4$ theory. The
method is general, however.

</DOC>
<DOC>
<DOCNO> 178984 </DOCNO>
Mass--dependence of the Lambda hypernuclear decay widths


  Two different approaches have been employed for the evaluation of the decay
widths of Lambda-hypernuclei (ranging from $^5_{\Lambda}$He to
$^{208}_{\Lambda}$Pb) with the polarization propagator method. In ref.[1], the
two-nucleon stimulated non-mesonic decay, $\Lambda NN\to NNN$, has been
parameterized phenomenologically by means of data on the pion-nucleus optical
potential. The other approach [2] consisted in a fully microscopic description
of the non-mesonic decays through the first order approximation of the
so-called bosonic-loop-expansion. Both calculations reproduce, with
approximately the same accuracy, the experimental decay rates for the whole
range of mass numbers considered.

</DOC>
<DOC>
<DOCNO> 100890 </DOCNO>
The Hard Lefschetz Theorem and the topology of semismall maps


  We introduce the notion of lef line bundles on a complex projective manifold.
We prove that lef line bundles satisfy the Hard Lefschetz Theorem, the
Lefschetz Decomposition and the Hodge-Riemann Bilinear Relations. We study
proper holomorphic semismall maps from complex manifolds and prove that, for
constant coefficients, the Decomposition Theorem is equivalent to the
non-degeneracy of certain intersection forms. We give a proof of the
Decomposition Theorem for the complex direct image of the constant sheaf when
the domain and the target are projective by proving that the forms in question
are non-degenerate. A new feature uncovered by our proof is that the forms are
definite.

</DOC>
<DOC>
<DOCNO> 118681 </DOCNO>
Conversion Law of Infrared Luminosity to Star Formation Rate for


  We construct a new algorithm for estimating the star formation rate (SFR) of
galaxies from their infrared (IR) luminosity by developing the theory of the IR
emission from a dusty H II region.
  The derived formula is ${\rm SFR}/(\MO {\rm yr^{-1}})=\{3.3\times
10^{-10}(1-\eta)/
  (0.4-0.2f+0.6 \epsilon)\}(L{\rm ^{obs}_{IR}}/\LO)$, where $f$ is the fraction
of ionizing photons absorbed by hydrogen,
  $\epsilon$ is the efficiency of dust absorption for nonionizing photons from
OB stars, and $\eta$ is the cirrus fraction of observed IR luminosity.
  The previous conversion formulae of SFR from the IR luminosity is applicable
to only the case where the observed IR luminosity is nearly equal to the
bolometric luminosity (starburst galaxies etc.), except for some empirical
formulae.
  On the other hand, our theoretical SFR is applicable to galaxies even with a
moderate star formation activity.
  That is, our simple and convenient formula is significantly useful for
estimating the SFR of various morphologies and types of galaxies --- from early
elliptical to late spiral and irregular galaxies, or from active starburst to
quiescent galaxies --- as far as they have neither an abnormal dust-to-gas
ratio nor an evident active galactic nucleus.

</DOC>
<DOC>
<DOCNO> 119759 </DOCNO>
Radio Properties of the Supernova Remnant N157B


  A new investigation of the supernova remnant (SNR) N157B was carried out with
the Australia Telescope Compact Array. Radio continuum images of the entire 30
Doradus region have been made at 3.5 and 6 cm wavelength with a resolution of
2". These data allow a high resolution study of the spectral index distribution
and polarization properties of both N157B and the nearby 30 Doradus nebula (the
latter will be reported in a subsequent paper). N157B is an extended Crab-type
SNR which may be beginning the transition to a composite remnant. There is
little apparent fine structure and the brightest radio region is several
parsecs from the probable position of the X-ray pulsar. The SNR has a radio
spectral index of -0.19 and is significantly polarized at 3.5 cm but not at
longer wavelengths.

</DOC>
<DOC>
<DOCNO> 169944 </DOCNO>
NMR Based Quantum Information Processing: Achievements and Prospects


  Nuclear magnetic resonance (NMR) provides an experimental setting to explore
physical implementations of quantum information processing (QIP). Here we
introduce the basic background for understanding applications of NMR to QIP and
explain their current successes, limitations and potential. NMR spectroscopy is
well known for its wealth of diverse coherent manipulations of spin dynamics.
Ideas and instrumentation from liquid state NMR spectroscopy have been used to
experiment with QIP. This approach has carried the field to a complexity of
about 10 qubits, a small number for quantum computation but large enough for
observing and better understanding the complexity of the quantum world. While
liquid state NMR is the only present-day technology about to reach this number
of qubits, further increases in complexity will require new methods. We sketch
one direction leading towards a scalable quantum computer using spin 1/2
particles. The next step of which is a solid state NMR-based QIP capable of
reaching 10-30 qubits.

</DOC>
<DOC>
<DOCNO> 101932 </DOCNO>
Isotropic steady states in galactic dynamics


  The present paper completes our earlier results on nonlinear stability of
stationary solutions of the Vlasov-Poisson system in the stellar dynamics case.
By minimizing the energy under a mass-Casimir constraint we construct a large
class of isotropic, spherically symmetric steady states and prove their
nonlinear stability against general, i. e., not necessarily symmetric
perturbations. The class is optimal in a certain sense, in particular, it
includes all polytropes of finite mass with decreasing dependence on the
particle energy.

</DOC>
<DOC>
<DOCNO> 9099 </DOCNO>
Exact solution of Calogero model with competing long-range interactions


  An integrable extension of the Calogero model is proposed to study the
competing effect of momentum dependent long-range interaction over the original
${1 \ov r^2}$ interaction. The eigenvalue problem is exactly solved and the
consequences on the generalized exclusion statistics, which appears to differ
from the exchange statistics, are analyzed. Family of dual models with
different coupling constants is shown to exist with same exclusion statistics.

</DOC>
<DOC>
<DOCNO> 9783 </DOCNO>
A Fermi liquid model for the overdoped and optimally doped cuprate


  This paper treats a number of issues of the cuprates, ranging from the spin
resonance peak and the linear one-particle scattering rate to the
superconducting transition, in the frame of a Fermi liquid model. Recent ARPES
expts. by Valla et al., Science vol. 285, 2110 (1999), and e-print
cond-mat/0003407, directly support the linearity of the one-particle scattering
rate everywhere in the Brillouin zone we obtained here. We show that the origin
of this linearity is the strong linear in energy term of the imaginary part of
the carrier susceptibility. This result yields directly a linear in temperature
resistivity and linear in 1/energy optical conductivity. We show that the low
energy dependence of the susceptibility can have a purely fermionic origin. We
introduce an antiferromagnetic ansatz for the susceptibility of the
carriers.Inter alia, this ansatz may explain the appearance of the spin
resonance peak (observed in neutron scattering) in the normal state of the
cuprates. Further, we obtain particularly high transition temperatures $T_c$
from our Eliashberg scheme by using this ansatz: we have a $d_{x^2-y^2}$ gap
with $T_c > 120 ^o$K for nearest neighbour hopping $t=250meV$.

</DOC>
<DOC>
<DOCNO> 84152 </DOCNO>
A Metric Theory of Gravity with Condensed Matter Interpretation


  We present a metric theory of gravity with Lagrangian 
    L = (8\pi G)^{-1}(\Xi g^{ii} - \Upsilon g^{00})\sqrt{-g}
    + L_{GR} + L_{matter} 
  motivated by classical equations 
    \partial_t \rho + \partial_i (\rho v^i) = 0
    \partial_t (\rho v^j) + \partial_i (\rho v^i v^j + p^{ij}) = 0 
  for a medium in Newtonian space-time. We obtain stable ``frozen stars'' instead of black holes and a ``big bounce'' instead of a big bang singularity.

</DOC>
<DOC>
<DOCNO> 119464 </DOCNO>
The Galactic Center He I Stars: Remains of a Dissolved Young Cluster?


  A massive young star cluster, initially embedded in its parent molecular
cloud, will spiral into the Galactic Center from $\lta 30m_6^{1/2}\pc$ during
the life-time of its most massive stars, if the combined total mass is $\sim
10^6m_6\msun$. On its way inwards the system loses most of its mass to the
strong tidal field, until the dense cluster core of high-mass stars is finally
disrupted near the central black hole. A simple model is presented to argue
that this scenario may under plausible conditions explain the observed location
and rotation of the Galactic Center HeI stars. Accretion of star clusters into
the Galactic Center could be recurrent, and play an important role in
regulating the activity of Sgr A$^\ast$.

</DOC>
<DOC>
<DOCNO> 13704 </DOCNO>
Reply to the Comment on `Glassy Transition in a Disordered Model for the


  We reply to the Comment by Hartmann (cond-mat/9908132) on our paper Phys.
Rev. Lett. 84 (2000) 2026 (also cond-mat/9907125).

</DOC>
<DOC>
<DOCNO> 169861 </DOCNO>
Long Distance, Unconditional Teleportation of Atomic States Via Complete


  This paper proposes a scheme for creating and storing quantum entanglement
over long distances. Optical cavities that store this long-distance
entanglement in atoms could then function as nodes of a quantum network, in
which quantum information is teleported from cavity to cavity. The
teleportation can be carried out unconditionally via measurements of all four
Bell states, using a method of sequential elimination.

</DOC>
<DOC>
<DOCNO> 68540 </DOCNO>
Neutrino Oscillations at an Entry-Level Neutrino Factory and Beyond


  We consider the parameters of an entry-level neutrino factory designed to
make the first observation of nu_e -> nu_mu oscillations, measure the
corresponding amplitude sin^2 2theta_{13}, and determine the sign of the
atmospheric-scale delta m_{32}^2 via matter effects. A 50 kt detector, a stored
muon energy E_mu geq 20 GeV and 10^{19} muon decays would enable these goals to
be met provided sin^2 2theta_{13} > 0.01. The determination of the sign of
delta m_{32}^2 also requires a baseline L geq 2000 km. An upgraded neutrino
factory with O(10^{20}) decays would enable the first observation of nu_e ->
nu_tau oscillations. With O(10^{21}) decays the effects of a large CP-phase
could be measured in the case of the large angle matter oscillation solution to
the solar neutrino anomaly. Our analysis includes a family of three-neutrino
models that can account for the atmospheric and solar neutrino oscillation
indications.

</DOC>
<DOC>
<DOCNO> 151234 </DOCNO>
Holographic Stress Tensor for Kerr-AdS Black Holes and Local Failure on


  We show that in general holographic stress tensor may contain a new term of
divergence of a spacelike unit normal acceleration. Then, it is shown that in
contrast to previous descriptions, a new stress tensor for Kerr-AdS solutions
can be a traceless one. Interestingly, this prescription entails a local
failure on the IR-UV connection.

</DOC>
<DOC>
<DOCNO> 150398 </DOCNO>
On the Consistency of Orbifolds


  Modular invariance is a necessary condition for the consistency of any closed
string theory. In particular, it imposes stringent constraints on the spectrum
of orbifold theories, and in principle determines their spectrum uniquely up to
discrete torsion classes. In practice, however, there are often ambiguities in
the construction of orbifolds that are a consequence of the fact that the
action of the orbifold elements on degenerate ground states is not unambiguous.
We explain that there exists an additional consistency condition, related to
the spectrum of D-branes in the theory, which eliminates these ambiguities. For
supersymmetric orbifolds this condition turns out to be equivalent to the
condition that supersymmetry is unbroken in the twisted sectors, but for
non-supersymmetric orbifolds it appears to be a genuinely new consistency
condition.

</DOC>
<DOC>
<DOCNO> 71849 </DOCNO>
Bounds on the Mass and Coupling Constant of Radion in the


  Assuming the Goldberger-Wise mechanism, we investigated the effective
potential at the one-loop level in the Randall-Sundrum theory. We found the
lower and upper bounds of the radion mass m_\phi and the radion-SM coupling
constant, 0.8 GeV \lesssim m_\phi \lesssim 260 GeV and 1400 GeV \lesssim
\Lambda_\phi \lesssim 1500 GeV for the one-loop level potential. These bounds
were determined from two constraints of warp factor = O(M_W/M_{Pl}) and Higgs
vev \simeq 246 GeV, which can produce strong bounds of m_\phi and \Lambda_\phi.
It is phenomenologically important that the one-loop allowed upper bound of the
radion mass is about five times larger than the tree-level one, but the radion
is still lighter than the Kaluza-Klein modes.

</DOC>
<DOC>
<DOCNO> 151687 </DOCNO>
Electromagnetic scattering on D3-brane spikes


  We consider scattering of electromagnetic plane waves on a D3-brane spike
which emanates normal to D3-barne in the extra space direction. We are
interested in studying physical effects on D3-brane which are produced by a
spike attached to D3-brane. We have observed that the spike sucks almost all
electromagnetic radiation and therefore acts like a black hole. This is because
absorption cross section for j=1 tends to a constant at low energy limit. This
behaviour is appealing for a string interpretation of the spike soliton because
the propagation of $j=1$ mode is indeed distinctive. Instead, the scattered
part of the radiation on a D3-brane tends to zero demonstrating non-Thompson
behaviour.

</DOC>
<DOC>
<DOCNO> 116872 </DOCNO>
Latest Developments from the S-DALINAC*


  The S-DALINAC is a 130 MeV superconducting recirculating electron accelerator
serving several nuclear and radiation physics experiments as well as driving an
infrared free-electron laser. A system of normal conducting rf resonators for
noninvasive beam position and current measurement was established. For the
measurement of gamma-radiation inside the accelerator cave a system of Compton
diodes has been developed and tested. Detailed investigations of the transverse
phasespace were carried out with a tomographical reconstruction method of
optical transition radiation spots. The method can be applied also to
non-Gaussian phasespace distributions. The results are in good accordance with
simulations. To improve the quality factor of the superconducting 3 GHz
cavities, an external 2K testcryostat was commissioned. The influence of
electro-chemical polishing and magnetic shielding is currently under
investigation. A digital rf-feedback-system for the accelerator cavities is
being developed in order to improve the energy spread of the beam of the
S-DALINAC.
  * Supported by the BMBF under contract no. 06 DA 820, the DFG under contract
no. Ri 242/12-1 and -2 and the DFG Graduiertenkolleg 'Physik und Technik von
Beschleunigern'

</DOC>
<DOC>
<DOCNO> 10809 </DOCNO>
A note on the generalization of the Telegrapher process to describe


  We reconsider the problem of diffusion of photons at a constant speed and
present a generalization of the Telegrapher process to higher dimensional
turbid media ($d>1$), where the photon can move along $2d$ directions. We
derive the equations for the probability density function using the ``formulae
of differentiation'' of Shapiro and Loginov. Our results agree with the earlier
work of Bogu\~{n}\'{a} et al. [M. Bogu\~{n}\'{a}, J.M. Porr\`{a} and J.
Masoliver, Phys. Rev. E {\bf 58}, 6992 (1998)], obtained by a different
approach, in the context of persistent random walks. Our work brings out
certain features that were not recognized in earlier work.
  PACS : 05.40.-a, 05.60.-k, 42.25.Dd

</DOC>
<DOC>
<DOCNO> 68415 </DOCNO>
Top quark rare decays in the standard model and beyond


  Theoretical predictions for the top quark rare decays are reviewed within and
beyond the standard model. Expectations at the CERN Large Hadron Collider are
discussed.

</DOC>
<DOC>
<DOCNO> 120745 </DOCNO>
Study of Hadronic Decays of the Z Boson at LEP


  This report summarizes four recent papers on the characteristics of the
hadronic decays of the Z by the LEP collaborations ALEPH, DELPHI and OPAL.

</DOC>
<DOC>
<DOCNO> 99857 </DOCNO>
Hard Tiling Problems with Simple Tiles


  It is well-known that the question of whether a given finite region can be
tiled with a given set of tiles is NP-complete. We show that the same is true
for the right tromino and square tetromino on the square lattice, or for the
right tromino alone. In the process, we show that Monotone 1-in-3
Satisfiability is NP-complete for planar cubic graphs. In higher dimensions, we
show NP-completeness for the domino and straight tromino for general regions on
the cubic lattice, and for simply-connected regions on the four-dimensional
hypercubic lattice.

</DOC>
<DOC>
<DOCNO> 8703 </DOCNO>
Theoretical interpretation of the experimental electronic structure of


  We adopt an atomistic pseudopotential description of the electronic structure
of self-assembled, lens shaped InAs quantum dots within the ``linear
combination of bulk bands'' method. We present a detailed comparison with
experiment, including quantites such as the single particle electron and hole
energy level spacings, the excitonic band gap, the electron-electron, hole-hole
and electron hole Coulomb energies and the optical polarization anisotropy. We
find a generally good agreement, which is improved even further for a dot
composition where some Ga has diffused into the dots.

</DOC>
<DOC>
<DOCNO> 150983 </DOCNO>
Vilkovisky-DeWitt Effective Action for Einstein Gravity on Kaluza-Klein


  We evaluate the divergent part of the Vilkovisky-DeWitt effective action for
Einstein gravity on even-dimensional Kaluza-Klein spacetimes of the form
$M^{4}\times S^{N}$. Explicit results are given for $N$=2, 4, and 6. Trace
anomalies for gravitons are also given for these cases. Stable Kaluza-Klein
configurations are sought, unsuccessfully, assuming the divergent part of the
effective action dominates the dynamics.

</DOC>
<DOC>
<DOCNO> 118119 </DOCNO>
Multiwavelength Observations of the Second Largest Known FR II Radio


  We present multi-frequency VLA, multicolor CCD imaging, optical spectroscopy,
and ROSAT HRI observations of the giant FR II radio galaxy NVSS 2146+82. This
galaxy, which was discovered by the NRAO VLA Sky Survey (NVSS), has an angular
extent of nearly 20' from lobe to lobe. The radio structure is normal for an FR
II source except for its large size and regions in the lobes with unusually
flat radio spectra. Our spectroscopy indicates that the optical counterpart of
the radio core is at a redshift of z=0.145, so the linear size of the radio
structure is ~4 h_50^-1 Mpc. This object is therefore the second largest FR II
known (3C 236 is ~6 h_50^-1 Mpc). Optical imaging of the field surrounding the
host galaxy reveals an excess number of candidate galaxy cluster members above
the number typically found in the field surrounding a giant radio galaxy. WIYN
HYDRA spectra of a sample of the candidate cluster members reveal that six
share the same redshift as NVSS 2146+82, indicating the presence of at least a
``rich group'' containing the FR II host galaxy. ROSAT HRI observations of NVSS
2146+82 place upper limits on the X-ray flux of 1.33 x 10^-13 ergs cm^-2 s^-1
for any hot IGM and 3.52 x 10^-14 ergs cm^-2 s^-1 for an X-ray AGN, thereby
limiting any X-ray emission at the distance of the radio galaxy to that typical
of a poor group or weak AGN. Several other giant radio galaxies have been found
in regions with overdensities of nearby galaxies, and a separate study has
shown that groups containing FR IIs are underluminous in X-rays compared to
groups without radio sources. We speculate that the presence of the host galaxy
in an optically rich group of galaxies that is underluminous in X-rays may be
related to the giant radio galaxy phenomenon.

</DOC>
<DOC>
<DOCNO> 102249 </DOCNO>
Symmetry, Singularities and Integrability in Complex Dynamics I: The


  Quadratic systems generated using Yang-Baxter equations are integrable in a
sense, but we display a deterioration in the possession of the Painlev\'e
property as the number of equations in each `integrable system' increases.
Certain intermediate systems are constructed and also tested for the Painlev\'e
property. The Lie symmetries are also computed for completeness.

</DOC>
<DOC>
<DOCNO> 70907 </DOCNO>
Neutralino Dark Matter Elastic Scattering in a Flat and Accelerating


  In SUGRA inspired supersymmetric models with universal boundary conditions
for the soft masses, the scalar cross section $\sigma_{scalar}$ for the elastic
neutralino--nucleon scattering is in general several orders of magnitude below
the sensitivity of current experiments. For large $\tan \beta$ and low
$M_{1/2}, m_0$ values, the theoretically predicted $\sigma_{scalar}$ can
approach the sensitivity of these experiments ($\approx 10^{-6} pb$) being at
the same time in agreement with recent cosmological data, which impose severe
restrictions on the CDM relic density, and with accelerator experiments which
put lower bounds on sparticle and Higgs boson masses. Further improvement of
the sensitivity of DAMA and CDMS experiments will probe the large $\tan \beta$
region of the parameter space in the vicinity of the boundaries of the
parameter space allowed by chargino and Higgs searches.

</DOC>
<DOC>
<DOCNO> 12440 </DOCNO>
Turning insulators into superconductors


  The recent observation by Batlogg and colleagues of superconductivity in an
organic field-effect transistor is reviewed.

</DOC>
<DOC>
<DOCNO> 99832 </DOCNO>
Fonctions z\^eta des hauteurs des espaces fibr\'es


  This paper is devoted to the estimation of the number of points of bounded
height on fibrations in toric varieties over algebraic varieties, generalizing
previous work by Strauch and the second author. Under reasonable hypotheses on
``Arakelov L-functions'' of the base, we show how to deduce a good estimate for
the open subset of the total space of the unerlying fibration in torus. In
passing, we improve drastically the error term for toric varieties themselves,
generalizing a theorem by de la Breteche over any number field.

</DOC>
<DOC>
<DOCNO> 81017 </DOCNO>
The k=2 string tension in four dimensional SU(N) gauge theories


  We calculate the k=2 string tensions in SU(4) and SU(5) gauge theories in 3+1
dimensions, and compare them to the k=1 fundamental string tensions. We find,
from the continuum extrapolation of our lattice calculations, that
K(k=2)/K(k=1) = 1.40(8) in the SU(4) gauge theory, and that K(k=2)/K(k=1) =
1.56(10) in SU(5). We remark upon the way this might constrain the dynamics of
confinement and the intriguing implications it might have for the mass spectrum
of SU(N) gauge theories. We also note that these results agree closely with the
MQCD-inspired conjecture that the SU(N) string tensions satisfy K(k)/K(1) =
sin(k.pi/N)/sin(pi/N).

</DOC>
<DOC>
<DOCNO> 68597 </DOCNO>
Models of Dynamical Supersymmetry Breaking with Gauged $U(1)_R$ Symmetry


  We present simple models of dynamical supersymmetry breaking with gauged
U(1)_R symmetry. The minimal supersymmetric standard model and supersymmetric
SU(5) GUT are considered as the visible sector. The anomaly cancellation
conditions for U(1)_R are investigated in detail and simple solutions of the
R-charge assignments are found. We show that this scenario of dynamical
supersymmetry breaking is phenomenologically viable with the gravitino mass of
order 1 TeV or 10 TeV.

</DOC>
<DOC>
<DOCNO> 68291 </DOCNO>
Exploiting Spin Correlations in Neutralino Production and Decay with


  We study the production process e^+ e^- -> chi^0_1 chi^0_2 and the subsequent
decay chi^0_2 -> chi^0_1 l^+ l^- with polarized e^+ and e^- beams, including
the spin correlations between production and decay. We work out the advantages
of polarizing both beams. We study in detail the angular distribution and the
forward--backward asymmetry of the decay lepton as well as the opening angle
distribution between the decay leptons. We investigate the dependence on the
masses of tilde{e}_L and tilde{e}_R and on the mixing character of the
neutralinos. In particular we study the dependence on the gaugino mass
parameter M_1.

</DOC>
<DOC>
<DOCNO> 100994 </DOCNO>
Krein's entire functions and the Bernstein approximation problem


  We extend two theorems of Krein concerning entire functions of Cartwright
class, and give applications for the Bernstein weighted approximation problem.

</DOC>
<DOC>
<DOCNO> 12726 </DOCNO>
Electromagnetic Force and the Maxwell Stress Tensor in Condensed Systems


  While the electromagnetic force is microscopically simply the Lorentz force,
its macroscopic form is more complicated, and given by expressions such as the
Maxwell stress tensor and the Kelvin force. Their derivation is fairly opaque,
at times even confusing, and their range of validity all but a well kept
secret. These circumstances unnecessarily reduce the usefulness and
trustworthiness of some key quantities in macroscopic electrodynamics.
  This article presents a thorough yet pedagogical derivation of the Maxwell
stress tensor and electromagnetic force in condensed media. It starts from
universally accepted inputs: conservation laws, thermodynamics and the Maxwell
equations. Simplifications are considered for various limits, especially the
equilibrium, with a range of validity assigned to each expression. Some
widespread misconceptions are scrutinized, and hidden ambiguities in popular
notations revealed.
  A number of phenomena typical of strongly polarizable systems, especially
ferrofluid, are then considered. In addition to enhancing the appreciation of
these systems, it helps to solidify the grasp of the introduced concepts and
derived formulas, and it demonstrates the ease with which the Maxwell stress
tensor can be handled, inviting theorists and experimentalists alike to embrace
this useful quantity.

</DOC>
<DOC>
<DOCNO> 117318 </DOCNO>
Time Reversal Symmetry Not Exist Actually In the Theories of Particle


  It is pointed out that the judgment condition of time reversal symmetry in
the processes of particle interaction is that the Hamiltioians of systems
satisfy the relation $\hat{H}(t)=\hat{H}^\ast(-t)$. But this condition can not
be satisfied actually in the current interaction theories, so the symmetry of
time reversal does not exist actually in the current theories of particle
interactions. In the current proof of time reversal symmetry, the relation
$\hat{H}(t)=\hat{H}^\ast(-t)$ is supposed to exist in advance, then the
translation relations between the time reversal operator and the field
quantities are deduced. So the current proof about the symmetry of time
reversal is not a real one.

</DOC>
<DOC>
<DOCNO> 170239 </DOCNO>
Schroedinger-Cat Entangled State Reconstruction in the Penning Trap


  We present a tomographic method for the reconstruction of the full entangled
quantum state for the cyclotron and spin degrees of freedom of an electron in a
Penning trap. Numerical simulations of the reconstruction of several
significant quantum states show that the method turns out to be quite accurate.

</DOC>
<DOC>
<DOCNO> 101192 </DOCNO>
Control for a class of nonlinear systems with a time-varying structure


  In this paper we present a direct adaptive control method for a class of
uncertain nonlinear systems with a time-varying structure. We view the
nonlinear systems as composed of a finite number of ``pieces,'' which are
interpolated by functions that depend on a possibly exogenous scheduling
variable. We assume that each piece is in strict feedback form, and show that
the method yields stability of all signals in the closed-loop, as well as
convergence of the state vector to a residual set around the equilibrium, whose
size can be set by the choice of several design parameters. The class of
systems considered here is a generalization of the class of strict feedback
systems traditionally considered in the backstepping literature. We also
provide design guidelines based on L-infinity bounds on the transient.

</DOC>
<DOC>
<DOCNO> 40498 </DOCNO>
Studies of Charmless Two-Body, Quasi-Two-Body and Three-Body B Decays


  Preliminary results are presented on a search for several exclusive charmless
hadronic B decays, from data collected by the BABAR detector near the
Upsilon(4S) resonance. These include two-body decay modes h^{+/-}h^{-/+}
three-body decay modes with final states h^{+/-}h^{-/+}h^{+/-} and
h^{+/-}h^{-/+}\pi^0, and quasi-two-body decay modes with final states X^0 h and
X^0 K_s^0, where h = pi or K and X^0 = eta^prime or omega. The measurement of
branching fractions for four decay modes, and upper limits for nine modes are
presented.

</DOC>
<DOC>
<DOCNO> 121382 </DOCNO>
Subaru Deep Survey I. Near-Infrared Observations


  Deep near-infrared images of a blank 2'x2' section of sky near the Galactic
north pole taken by Subaru Telescope are presented. The total integration times
of the J and K' bands are 12.1 hours and 9.7 hours, resulting in 5-sigma
limiting magnitudes of 25.1 and 23.5 mag, respectively. The numbers of sources
within these limiting magnitudes found with an automated detection procedure
are 385 in the J band and 350 in K'. Based on photometric measurements of these
sources, we present number count vs. magnitude relations, color vs. magnitude
diagrams, size vs. color relationships, etc. The slope of the galaxy number
count plotted against the AB magnitude scale is about 0.23 in the 22 to 26 AB
magnitude range of both bands. The spatial number density of galaxies as well
as the slopes in the faint-end region given by the Subaru Deep Field (SDF)
survey is consistent with those given by HST-NICMOS surveys as expressed on the
AB magnitude diagram. Several sources having very large J-K' color are found
including a few K' objects without detection at J. In addition, a number of
faint Galactic stars are also detected, most of which are assigned to
M-subdwarfs, together with a few brown dwarf candidates.

</DOC>
<DOC>
<DOCNO> 101211 </DOCNO>
Finiteness of simple homotopy type up to s-cobordism of aspherical


  In this paper we show that for a large class C of 4-manifolds each member of
C has only finitely many simple homotopy type upto s-cobordism. This result
generalizes a similar result of Hillman for certain complex surfaces. We also
present a correction in the proof of Hillman's result.

</DOC>
<DOC>
<DOCNO> 99797 </DOCNO>
Polynomials on Schreier's space


  We introduce a weakened version of the Dunford-Pettis property, and give
examples of Banach spaces with this property. In particular, we show that every
closed subspace of Schreier's space $S$ enjoys it. As an application, we
characterize the weak polynomial convergence of sequences, show that every
closed subspace of $S$ has the polynomial Dunford-Pettis property of Bistr\"om
et al. and give other polynomial properties of $S$.

</DOC>
<DOC>
<DOCNO> 178548 </DOCNO>
Chiral Three-Nucleon Forces from p-wave Pion Production


  Production of p-wave pions in nucleon-nucleon collisions is studied according
to an improved power counting that embodies the constraints of chiral symmetry.
Contributions from the first two non-vanishing orders are calculated. We find
reasonable convergence and agreement with data for a spin-triplet cross section
in $pp\to pp\pi^0$,with no free parameters. Agreement with existing data for a
spin-singlet cross section in $pp\to pn\pi^+$ constrains a short-range operator
shown recently to contribute significantly to the three-nucleon potential.

</DOC>
<DOC>
<DOCNO> 178640 </DOCNO>
The Neutron Halo in Heavy Nuclei Calculated with the Gogny Force


  The proton and neutron density distributions, one- and two-neutron separation
energies and radii of nuclei for which neutron halos are experimentally
observed, are calculated using the self-consistent Hartree-Fock-Bogoliubov
method with the effective interaction of Gogny. Halo factors are evaluated
assuming hydrogen-like antiproton wave functions. The factors agree well with
experimental data. They are close to those obtained with Skyrme forces and with
the relativistic mean field approach.

</DOC>
<DOC>
<DOCNO> 120287 </DOCNO>
Mid-infrared interferometry on spectral lines: I. Instrumentation


  The U. C. Berkeley Infrared Spatial Interferometer has been outfitted with a
filterbank system to allow interferometric observations of mid-infrared
spectral lines with very high spectral resolution (R ~ 10^5). This paper
describes the design, implementation, and performance of the matched 32-channel
filterbank modules, and new spectral line observations of Mars and IRC+10216
are used to demonstrate their scientific capability. In addition, observing
strategies are discussed for accurate calibration of fringe visibilities in
spectral lines, despite strong atmospheric fluctuations encountered in the
infrared.

</DOC>
<DOC>
<DOCNO> 13740 </DOCNO>
Ground State of a trapped Bose-Einstein Condensate in Two Dimensions;


  We consider the ground state of a trapped Bose-Einstein condensate in two
dimensions. In the mean-field approximation, the ground state density profile
satisfies the Gross-Pitaevskii equation. We compute the leading quantum
corrections to the density profile to second order in an expansion around the
Thomas-Fermi limit. By summing the ladder diagrams, we are generalizing
Schick's result for the ground state energy of a homogeneouns Bose gas to the
case of a trapped Bose gas.

</DOC>
<DOC>
<DOCNO> 151477 </DOCNO>
Flowing from a noncommmutative (OM) five brane via its supergravity dual


  The dual supergravity description of the flow between (2,0) five-brane theory
and the noncommutative five-brane (OM) theory is examined at critical
five-brane field strength. The self-duality of the field strength is shown to
arise as a consequence of the supergravity solution. Open membrane solutions
are examined in the background of the five-brane giving rise to an M analogue
of the noncommutative open string (NCOS) solution.

</DOC>
<DOC>
<DOCNO> 169735 </DOCNO>
Optimal local preparation of an arbitrary mixed state of two qubits.


  In this note we consider the problem of preparing a {\em single} copy of an
arbitrary two-qubit mixed state $\rho$ starting from an entangled pure state
$\psi$ and using only local operations assisted with classical communication.
We present an analytical expression for the minimal amount of pure state
entanglement required, and describe the corresponding local strategy. We also
examine optimal probabilistic generalizations of the previous process.

</DOC>
<DOC>
<DOCNO> 118655 </DOCNO>
Timing Noise in SGR 1806-20


  We have phase connected a sequence of RXTE PCA observations of SGR 1806-20
covering 178 days. We find a simple secular spin-down model does not adequately
fit the data. The period derivative varies gradually during the observations
between 8.1 and 11.7 * 10^-11 s/s (at its highest, ~40% larger than the long
term trend), while the average burst rate as seen with BATSE drops throughout
the time interval. The phase residuals give no compelling evidence for
periodicity, but more closely resemble timing noise as seen in radio pulsars.
The magnitude of the timing noise, however, is large relative to the noise
level typically found in radio pulsars. Combining these results with the noise
levels measured for some AXPs, we find all magnetar candidates have \Delta_8
values larger than those expected from a simple extrapolation of the
correlation found in radio pulsars. We find that the timing noise in SGR
1806-20 is greater than or equal to the levels found in some accreting systems
(e.g., Vela X-1, 4U 1538-52 and 4U 1626-67), but the spin-down of SGR 1806-20
has thus far maintained coherence over 6 years. Alternatively, an orbital model
with a period P_orb = 733 days provides a statistically acceptable fit to the
data. If the phase residuals are created by Doppler shifts from a
gravitationally bound companion, then the allowed parameter space for the mass
function (small) and orbital separation (large) rule out the possibility of
accretion from the companion sufficient to power the persistent emission from
the SGR.

</DOC>
<DOC>
<DOCNO> 13296 </DOCNO>
Exact Solution of an Exclusion Model in the Presence of a moving


  We study a recently introduced model which consists of positive and negative
particles on a ring. The positive (negative) particles hop clockwise
(counter-clockwise) with rate 1 and oppositely charged particles may swap their
positions with asymmetric rates q and 1. In this paper we assume that a finite
density of positively charged particles $\rho$ and only one negative particle
(which plays the role of an impurity) exist on the ring. It turns out that the
canonical partition function of this model can be calculated exactly using
Matrix Product Ansatz (MPA) formalism. In the limit of infinite system size and
infinite number of positive particles, we can also derive exact expressions for
the speed of the positive and negative particles which show a second order
phase transition at $q_c=2\rho$. The density profile of the positive particles
on the ring has a shock structure for $q \leq q_c$ and an exponential behaviour
with correlation length $\xi$ for $q \geq q_c$. It will be shown that the
mean-field results become exact at q=3 and no phase transition occurs for q>2.

</DOC>
<DOC>
<DOCNO> 121914 </DOCNO>
Torsional oscillations in the solar convection zone


  Recent analysis of the helioseismic observations indicate that the previously
observed surface torsional oscillations extend significantly downwards into the
solar convection zone.
  In an attempt to understand these oscillations, we study the nonlinear
coupling between the magnetic field and the solar differential rotation in the
context of a mean field dynamo model, in which the nonlinearity is due to the
action of the azimuthal component of the Lorentz force of the dynamo generated
magnetic field on the solar angular velocity. The underlying zero order angular
velocity is chosen to be consistent with the most recent helioseismic data.
  The model produces butterfly diagrams which are in qualitative agreement with
the observations. It displays torsional oscillations that penetrate into the
convection zone, and which with time migrate towards the equator. The period of
these oscillations is found to be half that of the period of the global
magnetic fields. This is compatible with the observed period of the surface
torsional oscillations. Inside the convection zone, this is a testable
prediction that is not ruled out by the observations so far available.

</DOC>
<DOC>
<DOCNO> 69491 </DOCNO>
Anatomy of the Proton Structure Functions in $\kappa$-factorization


  We present the first experiment-based parameterization of differential gluon
structure function, which is called upon in many applications. We compare
$\kappa$-factorization and DGLAP approaches and analyze properties of DGSF,
with special emphasis on soft-to-hard/hard-to-soft diffusion.

</DOC>
<DOC>
<DOCNO> 102789 </DOCNO>
Invitation to higher local fields, Part II, section 5: Harmonic analysis


  This work introduces author's approach to harmonic analysis on algebraic
groups over functional two-dimensional local fields. For a two-dimensional
local field a Hecke algebra which is formed by operators which integrate
pro-locally-constant complex functions over a non-compact domain is defined and
its properties are described.

</DOC>
<DOC>
<DOCNO> 152037 </DOCNO>
Note on Noncommutative Tachyon in Matrix Models


  The solution representing a brane-anti-brane system in matrix models breaks
the usual matrix spacetime symmetry. We show that the spacetime symmetry on the
branes is not breaking, rather appears as a combination of the matrix spacetime
transformation and a gauge transformation. As a result, the tachyon field,
itself an off-diagonal entry in longitudinal matrices, transforms nontrivially
under rotations, decomposing into tensors of different ranks. We also show that
the tachyon field can never be gauged away, and conjecture that this field is
related to the usual complex scalar tachyon by a field redefinition. We also
briefly discuss tachyon condensation.

</DOC>
<DOC>
<DOCNO> 12045 </DOCNO>
Temperature dependence and mechanisms for vortex pinning by periodic


  Pinning interactions between superconducting vortices in Nb and magnetic Ni
dots were studied as a function of current and temperature to clarify the
nature of pinning mechanisms. A strong current dependence is found for a square
array of dots, with a temperature dependent optimum current for the observation
of periodic pinning, that decreases with temperature as (1-T/Tc)3/2. This same
temperature dependence is found for the critical current at the first matching
field with a rectangular array of dots. The analysis of these results allows to
narrow the possible pinning mechanisms to a combination of two: the interaction
between the vortex and the magnetic moment of the dot and the proximity effect.
Moreover, for the rectangular dot array, the temperature dependence of the
crossover between the low field regime with a rectangular vortex lattice to the
high field regime with a square configuration has been studied. It is found
that the crossover field increases with decreasing temperature. This dependence
indicates a change in the balance between elastic and pinning energies,
associated with dynamical effects of the vortex lattice in the high field
range.

</DOC>
<DOC>
<DOCNO> 85336 </DOCNO>
Gravitational Energy-Momentum in the Tetrad and Quadratic Spinor


  In the Tetrad Representation of General Relativity, the energy-momentum
expression, found by Moller in 1961, is a tensor wrt coordinate transformations
but is not a tensor wrt local Lorentz frame rotations. This local Lorentz
freedom is shown to be the same as the six parameter normalized spinor degrees
of freedom in the Quadratic Spinor Representation of General Relativity. From
the viewpoint of a gravitational field theory in flat space-time, these extra
spinor degrees of freedom allow us to obtain a local energy-momentum density
which is a true tensor over both coordinate and local Lorentz frame rotations.

</DOC>
<DOC>
<DOCNO> 117781 </DOCNO>
Young Stellar Populations Around SN1987A


  We present the results of a study of the stellar population in a region of 30
pc radius around SN1987A, based on an analysis of multi-band HST-WFPC2 images.
  The effective temperature, radius and, possibly, reddening of each star were
determined for 21,955 stars by fitting the measured broad band magnitudes to
the ones calculated with model atmospheres. In addition, we have identified all
stars with Halpha equivalent widths in excess of 8 A, amounting to a total of
492 stars.
  An inspection to the HR diagram reveals the presence of several generations
of young stars, with ages between 1 and 150 Myrs, superposed on a much older
field population (0.6-6 Gyrs). A substantial fraction of young stars have ages
around 12 Myrs which is the stellar generation coeval to SN 1987A progenitor.
The youngest stars in the field appear to be strong-line T Tauri stars. This
constitute the first positive detection of low mass (about 1-2 Mo) Pre Main
Sequence (PMS) stars outside the Milky Way. Their positions in the HR diagram
appear to require that star formation in the LMC occurs with accretion rates
about 10 times higher than in the Milky Way, i.e. ~10^{-4} Mo/yr.
  SN1987A appears to belong to a loose, young cluster 12+/-2 Myrs old, in which
the slope of the present mass function is almost identical to Salpeter's for
masses above 3 Mo, but becomes much flatter for lower masses. On a large scale,
we find that the spatial distribution of massive stars and low-mass PMS stars
are conclusively different. This results casts doubts on the validity of an IMF
concept on a small scale (say, less than 10 pc). A preliminary analysis, done
for the whole field as a single entity, shows that the IMF slope for the young
population present over the entire region is steeper than Gamma ~ -1.7.

</DOC>
<DOC>
<DOCNO> 12151 </DOCNO>
spl(2,1) dynamical supersymmetry and suppression of ferromagnetism in


  The low energy spectrum of the ferromagnetic Kondo lattice model on a N-site
complete graph extended with on-site repulsion is obtained from the underlying
spl(2,1) algebra properties in the strong coupling limit. The ferromagnetic
ground state is realized for 1 and N+1 electrons only. We identify the large
density of states to be responsible for the suppression of the ferromagnetic
state and argue that a similar situation is encountered in the Kagome,
pyrochlore, and other lattices with flat bands in their one-particle density of
states.

</DOC>
<DOC>
<DOCNO> 10546 </DOCNO>
Logrithmic corrections to the RG flow for the two-dimensional bond


  Using the mapping of the partition function of the two-dimensional Ising
model onto a pfaffian we evaluate the domain wall free energy difference for
the pure and disordered Ising model close to the pure fixed point. Using this
method very large lattices can be studied exactly and we confirm that disorder
even including frustrating interactions indeed are irrelevant close to the pure
fixed point. The finite-size renormalization group flow shows a power-law
behavior modified by a logarithmic term that dominates for small lattice sizes.

</DOC>
<DOC>
<DOCNO> 150315 </DOCNO>
Some uses of moduli spaces in particle and field theory


  In this talk I shall try to give an elementary introduction to certain areas
of mathematical physics where the idea of moduli space is used to help solve
problems or to further our understanding. In the wide area of gauge theory, I
shall mention instantons, monopoles and duality. Then, under the general
heading of string theory, I shall indicate briefly the use of moduli space in
conformal field theory and $M$-theory.

</DOC>
<DOC>
<DOCNO> 84792 </DOCNO>
Chaos in a modified Henon-Heiles system describing geodesics in


  A Hamiltonian system with a modified Henon-Heiles potential is investigated.
This describes the motion of free test particles in vacuum gravitational
pp-wave spacetimes with both quadratic ("homogeneous") and cubic
("non-homogeneous") terms in the structural function. It is shown that, for
energies above a certain value, the motion is chaotic in the sense that the
boundaries separating the basins of possible escapes become fractal.
Similarities and differences with the standard Henon-Heiles and the monkey
saddle systems are discussed. The box-counting dimension of the basin
boundaries is also calculated.

</DOC>
<DOC>
<DOCNO> 101555 </DOCNO>
On rational extension of Heisenberg algebra


  Construction of rational extension for Heisenberg algebra with one pair of
generators is discussed.

</DOC>
<DOC>
<DOCNO> 13686 </DOCNO>
Superfluid Helium 3: Link between Condensed Matter Physics and Particle


  The discovery of the superfluid phases of Helium 3 in 1971 opened the door to
one of the most fascinating systems known in condensed matter physics.
Superfluidity of Helium 3, originating from pair condensation of Helium 3
atoms, turned out to be the ideal testground for many fundamental concepts of
modern physics, such as macroscopic quantum phenomena, (gauge-)symmetries and
their spontaneous breakdown, topological defects, etc. Thereby the superfluid
phases of Helium 3 enriched condensed matter physics enormously. In particular,
they contributed significantly - and continue to do so - to our understanding
of various other physical systems, from heavy fermion and high-Tc
superconductors all the way to neutron stars, particle physics, gravity and the
early universe. A simple introduction into the basic concepts and questions is
presented.

</DOC>
<DOC>
<DOCNO> 85137 </DOCNO>
Moving-mirror entropy


  We consider a quantized scalar field in a two-dimensional Minkowski spacetime
with a moving mirror and propose a definition of moving-mirror entropy
associated with temporarily inaccessible information about the future.

</DOC>
<DOC>
<DOCNO> 68170 </DOCNO>
Current Status of Radiative B Decays


  A current status report on radiative inclusive and exclusive B decays is
presented.

</DOC>
<DOC>
<DOCNO> 83186 </DOCNO>
On Redundancy Elimination Tolerant Scheduling Rules


  In (Ferrucci, Pacini and Sessa, 1995) an extended form of resolution, called
Reduced SLD resolution (RSLD), is introduced. In essence, an RSLD derivation is
an SLD derivation such that redundancy elimination from resolvents is performed
after each rewriting step. It is intuitive that redundancy elimination may have
positive effects on derivation process. However, undesiderable effects are also
possible. In particular, as shown in this paper, program termination as well as
completeness of loop checking mechanisms via a given selection rule may be
lost. The study of such effects has led us to an analysis of selection rule
basic concepts, so that we have found convenient to move the attention from
rules of atom selection to rules of atom scheduling. A priority mechanism for
atom scheduling is built, where a priority is assigned to each atom in a
resolvent, and primary importance is given to the event of arrival of new atoms
from the body of the applied clause at rewriting time. This new computational
model proves able to address the study of redundancy elimination effects,
giving at the same time interesting insights into general properties of
selection rules. As a matter of fact, a class of scheduling rules, namely the
specialisation independent ones, is defined in the paper by using not trivial
semantic arguments. As a quite surprising result, specialisation independent
scheduling rules turn out to coincide with a class of rules which have an
immediate structural characterisation (named stack-queue rules). Then we prove
that such scheduling rules are tolerant to redundancy elimination, in the sense
that neither program termination nor completeness of equality loop check is
lost passing from SLD to RSLD.

</DOC>
<DOC>
<DOCNO> 122908 </DOCNO>
The initial conditions of isolated star formation: IV - C18O


  We present C18O observations of the pre-stellar core L1689B, in the (J=3-2)
and (J=2-1) rotational transitions, taken at the James Clerk Maxwell Telescope
in Hawaii. We use a lambda-iteration radiative transfer code to model the data.
We adopt a similar form of radial density profile to that which we have found
in all pre-stellar cores, with a `flat' inner profile, steepening towards the
edge, but we make the gradient of the `flat' region a free parameter. We find
that the core is close to virial equilibrium, but there is tentative evidence
for core contraction. We allow the temperature to vary with a power-law form
and find we can consistently fit all of the CO data with an inverse temperature
gradient that is warmer at the edge than the centre. However, when we combine
the CO data with the previously published millimetre data we fail to find a
simultaneous fit to both data-sets without additionally allowing the CO
abundance to decrease towards the centre. This effect has been observed
qualitatively many times before, as the CO freezes out onto the dust grains at
high densities, but we quantify the effect. Hence we show that the combination
of mm/submm continuum and spectral line data is a very powerful method of
constraining the physical parameters of cores on the verge of forming stars.

</DOC>
<DOC>
<DOCNO> 152341 </DOCNO>
Supersymmetric Domain Wall and RG Flow from 4-Dimensional Gauged N=8


  By studying various, known extrema of 1) SU(3) sectors, 2) SO(5) sectors and
3) SO(3)xSO(3) sectors of gauged N =8 supergravity in four-dimensions, one
finds that the deformation of seven sphere \S^7 gives rise to non-trivial
renormalization group(RG) flow in three-dimensional boundary conformal field
theory from UV fixed point to IR fixed point. For SU(3) sectors, this leads to
four-parameter subspace of the supergravity scalar-gravity action and we
identify one of the eigenvalues of A_1 tensor of the theory with a
superpotential of scalar potential that governs RG flows on this subspace. We
analyze some of the structure of the superpotential and discuss first-order BPS
domain-wall solutions, using some algebraic relations between superpotential
and derivatives of it with respect to fields, that determine a (super)symmetric
kink solution in four-dimensional N =8 supergravity, which generalizes all the
previous considerations. The BPS domain-wall solutions are equivalent to
vanishing of variation of spin 1/2, 3/2 fields in the supersymmetry preserving
bosonic background of gauged N=8 supergravity. For SO(5) sectors, there exist
only nontrivial nonsupersymmetric critical points that are unstable and
included in SU(3) sectors. For SO(3)xSO(3) sectors, we construct the scalar
potential(never been written) explicitly and study explicit construction of
first-order domain-wall solutions.

</DOC>
<DOC>
<DOCNO> 117556 </DOCNO>
Low Mass Density Wide Field Far-IR/Submillimeter Telescope Systems


  Fundamentally new technology is described for constructing low areal mass
density (1kg/m^2), high precision (< 10micron RMS) reflectors scalable to large
apertures (10 to 20 meters) for use as the primary element of a telescope
system. A large reduction in mass is achieved by minimizing the mass of the
reflective surface using a high reflectivity metallic membrane. A wide field
diffraction limited telescope system can be constructed using the primary
reflector in conjunction with secondary and tertiary optics.

</DOC>
<DOC>
<DOCNO> 178624 </DOCNO>
Time-odd mean fields in the rotating frame: microscopic nature of


  The microscopic role of nuclear magnetism in rotating frame is investigated
for the first time in the framework of the cranked relativistic mean field
theory. It is shown that nuclear magnetism modifies the expectation values of
single-particle spin, orbital and total angular momenta along the rotational
axis effectively creating additional angular momentum. This effect leads to the
increase of kinematic and dynamic moments of inertia at given rotational
frequency and has an impact on effective alignments.

</DOC>
<DOC>
<DOCNO> 100293 </DOCNO>
Painleve-Calogero Correspondence Revisited


  We extend the work of Fuchs, Painlev\'e and Manin on a Calogero-like
expression of the sixth Painlev\'e equation (the ``Painlev\'e-Calogero
correspondence'') to the other five Painlev\'e equations. The Calogero side of
the sixth Painlev\'e equation is known to be a non-autonomous version of the
(rank one) elliptic model of Inozemtsev's extended Calogero systems. The fifth
and fourth Painlev\'e equations correspond to the hyperbolic and rational
models in Inozemtsev's classification. Those corresponding to the third, second
and first are seemingly new. We further extend the correspondence to the higher
rank models, and obtain a ``multi-component'' version of the Painlev\'e
equations.

</DOC>
<DOC>
<DOCNO> 118862 </DOCNO>
Apse Alignment of Narrow Eccentric Planetary Rings


  The boundaries of the Uranian epsilon, alpha, and beta rings can be fitted by
Keplerian ellipses. The pair of ellipses that outline a given ring share a
common line of apsides. Apse alignment is surprising because the quadrupole
moment of Uranus induces differential precession. We propose that rigid
precession is maintained by a balance of forces due to ring self-gravity,
planetary oblateness, and interparticle collisions. Collisional impulses play
an especially dramatic role near ring edges. Pressure-induced accelerations are
maximal near edges because there (1) velocity dispersions are enhanced by
resonant satellite perturbations, and (2) the surface density declines steeply.
Remarkably, collisional forces felt by material in the last 100 m of a 10 km
wide ring can increase equilibrium masses up to a factor of 100. New ring
surface densities are derived which accord with Voyager radio measurements. In
contrast to previous models, collisionally modified self-gravity appears to
allow for both negative and positive eccentricity gradients; why all narrow
planetary rings exhibit positive eccentricity gradients remains an open
question.

</DOC>
<DOC>
<DOCNO> 170508 </DOCNO>
Clifford algebras and universal sets of quantum gates


  In this paper is shown an application of Clifford algebras to the
construction of computationally universal sets of quantum gates for $n$-qubit
systems. It is based on the well-known application of Lie algebras together
with the especially simple commutation law for Clifford algebras, which states
that all basic elements either commute or anticommute.

</DOC>
<DOC>
<DOCNO> 84260 </DOCNO>
Logarithmic correction to the Bekenstein-Hawking entropy


  The exact formula derived by us earlier for the entropy of a four dimensional
non-rotating black hole within the quantum geometry formulation of the event
horizon in terms of boundary states of a three dimensional Chern-Simons theory,
is reexamined for large horizon areas. In addition to the {\it semiclassical}
Bekenstein-Hawking contribution to the area obtained earlier, we find a
contribution proportional to the logarithm of the area together with subleading
corrections that constitute a series in inverse powers of the area.

</DOC>
<DOC>
<DOCNO> 9915 </DOCNO>
Trapped condensates of atoms with dipole interactions


  We discuss in detail properties of trapped atomic condensates with
anisotropic dipole interactions. A practical procedure for constructing
anisotropic low energy pseudo potentials is proposed and justified by the
agreement with results of numerical multi-channel calculations. The time
dependent variational method is adapted to reveal several interesting features
observed in numerical solutions of condensate wave function. Collective low
energy shape oscillations and their stability inside electric fields are
investigated. Our results shed new light into macroscopic coherence properties
of interacting quantum degenerate atomic gases.

</DOC>
<DOC>
<DOCNO> 122449 </DOCNO>
Lyman alpha line formation in starbursting galaxies I. Moderately thick,


  We investigate the Lyman alpha line transfer in nearby and high redshift
starbursting galaxies, where the effect of high optical depths and the role of
dust in the scattering medium are expected to be conspicuous and should be
treated in a very careful manner. We present our first results in dustless,
static, and uniform HI media with moderate Lyman alpha line center optical
depths \tau_0=10^{3-6}. We assume that the temperatures of media to be
T=10^{1-4}K, and use a Monte Carlo technique. We investigate the basic
processes of the line transfer and confirm the criterion of a\tau_0>10^3 for
the validity of diffusion approximation suggested by Neufeld in 1990, where $a$
is the Voigt parameter. Adopting the model suggested by Tenorio-Tagle et al.,
we performed calculations on the Lyman alpha line formation for each
evolutionary stage of an expanding supershell. The emergent Lyman alpha
profiles are characterized by the double peaks and the absorption trough at the
line center. We found that the absorption troughs expected in most of the
evolutionary stages are not wide enough to be observed with current
instruments. However, the absorption trough in the Lyman alpha emission profile
from an expanding recombining supershell can be marginally detected.

</DOC>
<DOC>
<DOCNO> 122363 </DOCNO>
The Initial Mass Function in the Galactic Center


  The Galactic Center contains the most massive young clusters in the Galaxy
and serves as the closest example of a massive starburst region. Our recent
results suggest that the Galactic Center environment produces massive clusters
with relatively flat initial mass functions, as might be expected on
theoretical grounds. I will discuss these recent results, along with evidence
for star formation in the immediate vicinity of the super massive black hole at
the Galactic Center. The results of this work might be useful in extrapolating
to other galactic centers with similar conditions, as well as other starburst
regions.

</DOC>
<DOC>
<DOCNO> 119824 </DOCNO>
The 1-point PDF of the Initial Conditions of our Local Universe from the


  The algorithm ZTRACE of Monaco & Efstathiou (1999) is applied to the IRAS
PSCz catalogue to reconstruct the initial conditions of our local Universe with
a resolution down to ~5 Mpc/h. The 1-point PDF of the reconstructed initial
conditions is consistent with the assumptions that (i) IRAS galaxies trace mass
on scales of ~5 Mpc/h, and (ii) the statistics of primordial density
fluctuations is Gaussian. We use simulated PSCz catalogues, constructed from
N-body simulations with Gaussian initial conditions, to show that local
non-linear bias can cause the recovered initial PDF (assuming no bias) to be
non-Gaussian. However, for plausible bias models, the distortions of the
recovered PDF would be difficult to detect using the volume finely sampled by
the PSCz catalogue. So, for Gaussian initial conditions, a range of bias models
remain compatible with our PSCz reconstruction results.

</DOC>
<DOC>
<DOCNO> 179048 </DOCNO>
Constraint Molecular Dynamics approach to Fermionic systems


  We propose a Constraint Molecular Dynamics model for Fermionic system. In
this approach the equations of motion of wave packets for the nuclear many-body
problem are solved by imposing that the one-body occupation probability
$\bar{f}(r,p,t)$ can assume only values less or equal to 1. This condition
reflects the Fermionic nature of the studied systems and it is implemented with
a fast algorithm which allows also the study of the heaviest colliding system.
The parameters of the model have been chosen to reproduce the average binding
energy and radii of nuclei in the mass region $A=30\sim 208$. Some comparison
to data is given.

</DOC>
<DOC>
<DOCNO> 120420 </DOCNO>
Suppression of giant planet formation in stellar clusters


  Photoevaporation driven by the ultraviolet radiation from massive stars
severely limits the lifetime of protoplanetary discs around stars formed within
stellar clusters. I investigate the resulting influence of clustered
environments on the probability of giant planet formation, and show that for
clusters as rich, or richer than, Orion, the time available for planet
formation is likely to be limited to the length of any delay between low mass
and high mass star formation. Under popular models for the formation of massive
planets, the fraction of stars with giant planets in rich clusters is expected
to be substantially suppressed as compared to less clustered star formation
environments.

</DOC>
<DOC>
<DOCNO> 100330 </DOCNO>
N=4 Superconformal Mechanics and the Potential Structure of AdS Spaces


  The dynamics of an N=4 spinning particle in a curved background is described
using the N=4 superfield formalism. The $SU(2)_{local}\times SU(2)_{global}$
N=4 superconformal symmetry of the particle action requires the background to
be a real "K\"ahler-like" manifold whose metric is generated by a sigma-model
superpotential. The anti-de-Sitter spaces are shown to belong to this class of
manifolds.

</DOC>
<DOC>
<DOCNO> 118219 </DOCNO>
A strong jet/cloud interaction in the Seyfert galaxy IC 5063: VLBI


  We present 21-cm HI line and 13-cm continuum observations, obtained with the
Australian Long Baseline Array, of the Seyfert 2 galaxy IC 5063. This object
appears to be one of the best examples of Seyfert galaxies where shocks
produced by the radio plasma jet influence both the radio as well as the
near-infrared emission. The picture resulting from the new observations of IC
5063 confirms and completes the one derived from previous Australia Telescope
Compact Array (ATCA) lower resolution observations. A strong interaction
between the radio plasma ejected from the nucleus and a molecular cloud of the
ISM is occurring at the position of the western hot spot, about 0.6 kpc from
the active nucleus. Because of this interaction, the gas is swept up, forming,
around the radio lobe, a cocoon-like structure where the gas is moving at high
speed. Due to this, part of the molecular gas is dissociated and becomes
neutral or even ionised if the UV continuum produced by the shocks is hard and
powerful enough. The main component detected in the VLBI HI absorption profile
has a central velocity of 2786 km/s and is therefore blue-shifted 614 km/s with
respect to the systemic velocity. Its peak optical depth is 5.4 %. The
corresponding column density of the detected absorption, for a spin temperature
of 100 K, is N_HI ~ 2x10^21 atoms cm^-2. The HI absorption properties observed
in IC 5063 appear different from those observed in other Seyfert galaxies,
where the HI absorption detected is attributed to undisturbed foreground gas
associated with the large-scale galaxy disk.

</DOC>
<DOC>
<DOCNO> 170225 </DOCNO>
All inseparable two-mode Gaussian continuous variable states are


  We show that all entangled Gaussian states of two infinite dimensional
systems can be distilled to maximally entangled states in finite dimensions.
The distillation protocol involves local squeezing operations, local homodyne
measurements with ancilla systems prepared in coherent states as well as local
joint measurements of the total number operator of two copies of the state.

</DOC>
<DOC>
<DOCNO> 174549 </DOCNO>
Direct Photon Production in 158 AGeV Pb+Pb Collisions


  A measurement of direct photon production in Pb+Pb collisions at 158 AGeV has
been carried out in the CERN WA98 experiment. The invariant yield of direct
photons in central collisions is extracted as a function of transverse momentum
in the interval 0.5 < pT < 4 GeV/c. A significant direct photon signal,
compared to statistical and systematical errors, is seen at pT > 1.5 GeV/c. The
results constitute the first observation of direct photons in ultrarelativistic
heavy-ion collisions which could be significant for diagnosis of quark gluon
plasma formation.

</DOC>
<DOC>
<DOCNO> 69244 </DOCNO>
Confidence Intervals and Upper Bounds for Small Signals in the Presence


  We discuss a new method for setting limits on small signals in the presence
of background noise. The method is based on a combination of a two dimensional
confidence region and the large sample approximation to the likelihood ratio
test statistic. It automatically quotes upper limits for small signals and
two-sided confidence intervals for larger samples. We show that this method
gives the correct coverage and also has good power.

</DOC>
<DOC>
<DOCNO> 9250 </DOCNO>
Laterally coupled few-electron quantum dots


  We present ground-state calculations for laterally coupled quantum dots
containing 2, 4, and 8 electrons. As our emphasis is on spin effects our
results are obtained by applying spin-density functional theory (SDFT). By
varying the distance between the centers of the coupled quantum dots, the
transition from weak to strong coupling situation is realized. For the
2-electron system we also apply the Heitler-London approximation and analytical
concepts to check the reliability of SDFT calculations in this case. In
addition we discuss the features of the Coulomb staircase of laterally coupled
quantum dots in the weak and strong coupling regimes in comparison to that of a
circular parabolic quantum dot.

</DOC>
<DOC>
<DOCNO> 99977 </DOCNO>
Four multiplicative cohomology theorems


  I try to find natural statement and proof of the de Rham Theorem and of other
cohomology theorems.

</DOC>
<DOC>
<DOCNO> 71440 </DOCNO>
On convergence of the ChPT HFF expansion for one loop contribution to


  We consider the application of heavy fermion formalism based chiral
perturbation theory to meson production in nucleon-nucleon collisions. It is
shown that for one loop contributions the heavy fermion formalism expansion
corrections for the nucleon propagator produce infinite series of correction
terms which are of the same momentum power order. This destroys the one-to-one
correspondence between the perturbative and small momentum expansion and thus
negates the application of any finite order heavy fermion formalism chiral
perturbation theory to the $NN\to NN \pi$ reactions.

</DOC>
<DOC>
<DOCNO> 122040 </DOCNO>
The Two Micron All-Sky Survey: Removing the Infrared Foreground


  We introduce the properties of the Two Micron All-Sky Survey (2MASS) survey
for IAU Symposium 204. 2MASS is a near-infrared survey of the entire sky
characterized by high reliability and completeness. Catalogs and images for 47%
of the sky are now available online. This data release has been used by Wright
(2000) and Cambresy et al. (2000) to subtract the stellar foreground at 1.25
and 2.2 microns from COBE DIRBE data, revealing the cosmological near-infrared
background.

</DOC>
<DOC>
<DOCNO> 116835 </DOCNO>
Results of an RF Pulsed Heating Experiment at SLAC


  Results are reported from an experiment on RF pulsed heating of copper at
SLAC. Damage in the form of cracks may be induced on the surface after the
application of many pulses of RF. The experiment consists of two circularly
cylindrical cavities operated in the TE011 mode at a resonant frequency of
11.424 GHz. Each cavity received 8.5 MW, 1.2 microsecond pulses at 60 Hz
corresponding to a calculated temperature rise of 120 K on the copper surface.
After 5.5 x 10^7 pulses, the experiment was stopped and the copper surfaces
were examined. Damage is present on the area of the surface where the maximum
heating occurred.

</DOC>
<DOC>
<DOCNO> 101360 </DOCNO>
A Semi-Classical Approach to Gravitation, Mass and Spin


  A simple geometric four-dimensional theory is discussed in which gravitation,
mass, spin, energy conservation and other related concepts can be viewed as
consequences of a certain weak quantum principle.

</DOC>
<DOC>
<DOCNO> 119423 </DOCNO>
Bar Dissolution in Prolate Halos


  The time evolution of barred structures is examined under the influence of
the external forces exerted by a spherical halo and by prolate halos. In
particular, galaxy disks are placed in the plane including the major axis of
prolate halos, whose configuration is often found in cosmological simulations.
N-body disks in fixed external halo fields are simulated, so that bars are
formed via dynamical instability. In the subsequent evolution, the bars in
prolate halos dissolve gradually with time, while the bar pattern in a
spherical halo remains almost unchanged to the end of the simulation. The decay
times of the bars suggest that they can be destroyed in a time smaller than a
Hubble time. Our results indicate that this dissolution process could occur in
real barred galaxies, if they are surrounded by massive dark prolate halos, and
the configuration adopted here is not unusual from the viewpoint of galaxy
formation. For a prolate halo model, an additional simulation that is
restricted to two-dimensional in-plane motions has also ended up with similar
bar dissolution. This means that the vertical motions of disk stars do not play
an essential role in the bar dissolution demonstrated here.

</DOC>
<DOC>
<DOCNO> 9699 </DOCNO>
Charge dynamics in doped triangular antiferromagnets


  Within the framework of the fermion-spin theory based on the charge-spin
separation, the charge dynamics of the doped antiferromagnet on a triangular
lattice is studied. The holon part is treated by using the loop expansion to
the second order. It is shown that the charge dynamics is mainly caused by
charged holons moving in the background of spinon excitations. The optical
conductivity spectrum shows an unusual behavior at low energies and an
anomalous midinfrared band, while the resistivity exhibits a nonlinearity in
temperatures.

</DOC>
<DOC>
<DOCNO> 179006 </DOCNO>
Effect of nuclear structure on Type Ia supernova nucleosynthesis


  The relationship among nuclear structure, the weak processes in nuclei, and
astrophysics becomes quite apparent in supernova explosion and nucleosynthesis
studies. In this brief article, I report on progress made in the last few years
on calculating electron capture and beta-decay rates in iron-group nuclei. I
also report on applications of these rates to Type-Ia nucleosynthesis studies.

</DOC>
<DOC>
<DOCNO> 71649 </DOCNO>
The Standard Electroweak Theory and Beyond


  1. Introduction, 2. Gauge Theories, 3. The Standard Model of Electroweak
Interactions, 4. The Higgs Mechanism, 5. The CKM Matrix, 6. Renormalisation and
Higher Order Corrections, 7. Why we do Believe in the Standard Model: Precision
Tests, 7.1.Precision Electroweak Data and the Standard Model, 7.2.A More
General Analysis of Electroweak Data, 8. Why we do not Believe in the Standard
Model, 8.1.Conceptual Problems, 8.2.Hints from Experiment, -8.2.1 Unification
of Couplings, -8.2.2 Dark Matter, -8.2.3 Neutrino Masses, -8.2.4 Baryogenesis,
9. Status of the Search for the Higgs and for New Physics, 10.Conclusion

</DOC>
<DOC>
<DOCNO> 69408 </DOCNO>
Decaying neutrino and a high cosmological baryon density


  The low second acoustic peak in the recent Boomerang data may indicate a
cosmological baryon density which is larger than allowed by standard big bang
nucleosynthesis.
  We show that the decay of the tau-neutrino: nu_tau -> nu_e + phi, where nu_e
is the electron neutrino and phi is a scalar, essentially can assure agreement
between BBN calculations and light element observations for a large baryon
density.

</DOC>
<DOC>
<DOCNO> 120988 </DOCNO>
Unidentified Infrared Emission Bands in the Diffuse Interstellar Medium


  Using the Mid-Infrared Spectrometer on board the Infrared Telescope in Space
and the low-resolution grating spectrometer (PHT-S) on board the Infrared Space
Observatory, we obtained 820 mid-infrared (5 to 12 $\mu$m) spectra of the
diffuse interstellar medium (DIM) in the Galactic center, W51, and Carina
Nebula regions. These spectra indicate that the emission is dominated by the
unidentified infrared (UIR) emission bands at 6.2, 7.7, 8.6, and 11.2 $\mu$m.
The relative band intensities (6.2/7.7 $\mu$m, 8.6/7.7 $\mu$m, and 11.2/7.7
$\mu$m) were derived from these spectra, and no systematic variation in these
ratios was found in our observed regions, in spite of the fact that the
incident radiation intensity differs by a factor of 1500. Comparing our results
with the polycyclic aromatic hydrocarbons (PAHs) model for the UIR band
carriers, PAHs in the DIM have no systematic variation in their size
distribution, their degree of dehydrogenation is independent of the strength of
UV radiation field, and they are mostly ionized. The latter finding is
incompatible with past theoretical studies, in which a large fraction of
neutral PAHs is predicted in this kind of environment. A plausible resolution
of this discrepancy is that the recombination coefficients for electron and
large PAH positive ion are by at least an order of magnitude less than those
adopted in past theoretical studies. Because of the very low population of
neutral state molecules, photoelectric emission from interstellar PAHs is
probably not the dominant source of heating of the diffuse interstellar gas.
The present results imply constant physical and chemical properties of the
carriers of the UIR emission bands in the DIM.

</DOC>
<DOC>
<DOCNO> 9385 </DOCNO>
Spanning Trees on Graphs and Lattices in d Dimensions


  The problem of enumerating spanning trees on graphs and lattices is
considered. We obtain bounds on the number of spanning trees $N_{ST}$ and
establish inequalities relating the numbers of spanning trees of different
graphs or lattices. A general formulation is presented for the enumeration of
spanning trees on lattices in $d\geq 2$ dimensions, and is applied to the
hypercubic, body-centered cubic, face-centered cubic, and specific planar
lattices including the kagom\'e, diced, 4-8-8 (bathroom-tile), Union Jack, and
3-12-12 lattices. This leads to closed-form expressions for $N_{ST}$ for these
lattices of finite sizes. We prove a theorem concerning the classes of graphs
and lattices ${\cal L}$ with the property that $N_{ST} \sim \exp(nz_{\cal L})$
as the number of vertices $n \to \infty$, where $z_{\cal L}$ is a finite
nonzero constant. This includes the bulk limit of lattices in any spatial
dimension, and also sections of lattices whose lengths in some dimensions go to
infinity while others are finite. We evaluate $z_{\cal L}$ exactly for the
lattices we considered, and discuss the dependence of $z_{\cal L}$ on d and the
lattice coordination number. We also establish a relation connecting $z_{\cal
L}$ to the free energy of the critical Ising model for planar lattices ${\cal
L}$.

</DOC>
<DOC>
<DOCNO> 70452 </DOCNO>
On the two kinds of vector particles


  All known elementary vector particles, the photon, Z, W and the gluons, are
described by the gauge theory. They belong to the real representation (1/2,1/2)
of the Lorentz group. On the other hand inequivalent representations (1,0) and
(0,1) also correspond to particles with spin 1. It is natural to suppose that,
along with the known vector particles, the new particles can exist. Evidence
for the existence of these particles in nature is the presence of the
axial-vector meson resonances with quantum numbers 1^{+-}. Other indications
for their existence are discussed. The signatures of their contributions into
different physical processes are presented.

</DOC>
<DOC>
<DOCNO> 116355 </DOCNO>
Gravitational potential and energy of homogeneous rectangular


  Gravitational potential and gravitational energy are presented in analytical
form for homogeneous rectangular parallelepiped.

</DOC>
<DOC>
<DOCNO> 100533 </DOCNO>
Ordered group invariants for one-dimensional spaces


  We show that the Bruschlinsky group with the winding order is a homeomorphism
invariant for a class of one-dimensional inverse limit spaces. In particular we
show that if a presentation of an inverse limit space satisfies the Simplicity
Condition, then the Bruschlinsky group with the winding order of the inverse
limit space is a dimension group and is a quotient of the dimension group with
the standard order of the adjacency matrices associated with the presentation.

</DOC>
<DOC>
<DOCNO> 9775 </DOCNO>
The High Magnetic Field Phase Diagram of a Quasi-One Dimensional Metal


  We present a unique high magnetic field phase of the quasi-one dimensional
organic conductor (TMTSF)$_2$ClO$_4$. This phase, termed "Q-ClO$_4$", is
obtained by rapid thermal quenching to avoid ordering of the ClO$_4$ anion. The
magnetic field dependent phase of Q-ClO$_4$ is distinctly different from that
in the extensively studied annealed material. Q-ClO$_4$ exhibits a spin density
wave (SDW) transition at $\approx$ 5 K which is strongly magnetic field
dependent. This dependence is well described by the theoretical treatment of
Bjelis and Maki. We show that Q-ClO$_4$ provides a new B-T phase diagram in the
hierarchy of low-dimensional organic metals (one-dimensional towards
two-dimensional), and describe the temperature dependence of the of the quantum
oscillations observed in the SDW phase.

</DOC>
<DOC>
<DOCNO> 118773 </DOCNO>
Statistical Study of Short Quiescent Times Between Flares


  The study of the statistical distribution of short quiescent times ($\le$ 30
minutes) between solar flares has been investigated on a 1D MHD model. A power
law behaviour is found which indicates the existence of sympathetic flaring.
This prediction is supported by recent observations.

</DOC>
<DOC>
<DOCNO> 150660 </DOCNO>
Reflexive Polyhedra and their Applications in String and F-theory


  This is an informal introduction to the concept of reflexive polyhedra and
some of their most important applications in perturbative and non-perturbative
string physics. Following the historical development, topics like mirror
symmetry, gauged linear sigma models, and the geometrical structures relevant
to string and F-theory dualities are discussed. Finally some recent
developments concerning the classification of reflexive polyhedra are
mentioned.

</DOC>
<DOC>
<DOCNO> 151890 </DOCNO>
Quantum Aspects of Black Hole Entropy


  This survey intends to cover recent approaches to black hole entropy which
attempt to go beyond the standard semiclassical perspective. Quantum
corrections to the semiclassical Bekenstein-Hawking area law for black hole
entropy, obtained within the quantum geometry framework, are treated in some
detail. Their ramification for the holographic entropy bound for bounded
stationary spacetimes is discussed. Four dimensional supersymmetric extremal
black holes in string-based N=2 supergravity are also discussed, albeit more
briefly.

</DOC>
<DOC>
<DOCNO> 68968 </DOCNO>
Measuring Leptonic CP Violation by Low Energy Neutrino Oscillation


  We uncover an interesting phenomenon that neutrino flavor transformation in
slowly varying matter density imitates almost exactly that of vacuum neutrino
oscillation under suitably chosen experimental parameters. It allows us to have
relatively large CP violating measure \Delta P \equiv P(\nu_{\mu} \to \nu_e) -
P(\bar{\nu}_{\mu} \to \bar{\nu}_e) which is essentially free from matter effect
contamination. We utilize this phenomenon to design a low-energy long-baseline
neutrino oscillation experiment to measure the leptonic CP violating phase.

</DOC>
<DOC>
<DOCNO> 120968 </DOCNO>
Distribution of dust and stars in the Galaxy


  Using far-infrared 240 micron and near-infrared K band data from the
COBE/DIRBE instrument, we model the Galactic stellar and dust distribution.
Making the assumption that the Galaxy is transparent in the 240 micron band,
the dust emission is modeled using the following components: a warped
exponential disk of scale length 0.26 R_sun, a spiral arm component as mapped
by HII regions, and a feature coinciding with the local (Orion) arm. The dust
distribution is used to calculate absorption in the K band, and the stellar
emission is likewise modeled with a warped exponential disk, with a scale
length of 0.29 R_sun, and a spiral arm component. Models of the K band emission
in the Galactic plane indicate that in this waveband a two arm spiral dominates
the nonaxisymmetric emission. The warp is evident in both the dust and stellar
component, and is found to start within the Solar Circle.

</DOC>
<DOC>
<DOCNO> 9008 </DOCNO>
On the controversy over the stochastic density functional equations


  This letter aims at justifying the stochastic equations in terms of the
number density variable, which are still controversial, via complementing
Dean's approach [Dean D S 1996 {\itshape J. Phys. A} {\bf 29} L613]. Our course
is twofold: First, we demonstrate that standard manipulations straightforwardly
transform the stochastic equation of density {\itshape operator}, derived by
Dean, to the Fokker-Planck equation for the (c-number) density distribution
functional $P(\{\rho\},t)$. Moreover, we verify the associated static solution
of $P(\{\rho\},t)$ with the help of the conditional grand canonical partition
function.

</DOC>
<DOC>
<DOCNO> 101387 </DOCNO>
Simplifying triangulations of S^3


  In this paper we describe a procedure to simplify any given triangulation of
the 3-sphere using Pachner moves. We obtain an explicit exponential-type bound
on the number of Pachner moves needed for this process. This leads to a new
recognition algorithm for the 3-sphere.

</DOC>
<DOC>
<DOCNO> 68916 </DOCNO>
Chiral aspects of hadron structure


  Chiral loop corrections for hadronic properties are considered in a
constituent quark model. It is emphasized that the correct implementation of
such corrections requires a sum over intermediate hadronic states. The leading
non-analytic corrections are very important for baryon magnetic moments and
explain the failure of the sum rule
$(\mu_{\Sigma^{+}}+2\mu_{\Sigma^{-}})/\mu_{\Lambda}=-1$ predicted by the
constituent quark model.

</DOC>
<DOC>
<DOCNO> 10778 </DOCNO>
Reply to the ``Comment on `quantum backaction of optical observations on


  In our paper we estimated the quantum backaction of dispersive imaging with
off-resonant light on Bose-Einstein condensates. We have calculated the rates
of the two processes involved, phase diffusion and depletion of the condensate.
We compare here the depletion rate obtained within our model limitations to the
Rayleigh scattering rate, both having the same physical origin: dispersive
interaction of light with matter. We show that residual absorption sets indeed
the limit of dispersive imaging.

</DOC>
<DOC>
<DOCNO> 83283 </DOCNO>
Systematic Performance Evaluation of Multipoint Protocols


  The advent of multipoint (multicast-based) applications and the growth and
complexity of the Internet has complicated network protocol design and
evaluation.
  In this paper, we present a method for automatic synthesis of worst and best
case scenarios for multipoint protocol performance evaluation.
  Our method uses a fault-oriented test generation (FOTG) algorithm for
searching the protocol and system state space to synthesize these scenarios.
The algorithm is based on a global finite state machine (FSM) model. We extend
the algorithm with timing semantics to handle end-to-end delays and address
performance criteria. We introduce the notion of a virtual LAN to represent
delays of the underlying multicast distribution tree.
  As a case study, we use our method to evaluate variants of the timer
suppression mechanism, used in various multipoint protocols, with respect to
two performance criteria: overhead of response messages and response time.
Simulation results for reliable multicast protocols show that our method
provides a scalable way for synthesizing worst-case scenarios automatically. We
expect our method to serve as a model for applying systematic scenario
generation to other multipoint protocols.

</DOC>
<DOC>
<DOCNO> 151884 </DOCNO>
Local observed time and redshift in curved spacetime


  Using the observed time and spatial intervals defined originally by Einstein
and the observation frame in the vierbein formalism, we propose that in curved
spacetime, for a wave received in laboratories, the observed frequency is the
changing rate of the phase of the wave relative to the local observable time
scale and the momentum the changing rate of the phase relative to the local
observable spatial length scale. The case of Robertson-Walker universe is
especially considered.

</DOC>
<DOC>
<DOCNO> 85520 </DOCNO>
Parametrization of singularities of the Demia\'{n}ski-Newman spacetimes


  We propose a new presentation of the Demia\'{n}ski-Newman (DN) solution of
the axisymmetric Einstein equations. We introduce new dimensionless parameters
$p$, $q$ and $s$, but keeping the Boyer-Lindquist coordinate transformation
used for the Kerr metric in the Ernst method. The family of DN metrics is
studied and it is shown that the main role of $s$ is to determine the
singularities, which we obtain by calculating the Riemann tensor components and
the invariants of curvature. So, $s$ reveals itself as the parameter of the
singular rings on the inner ergosphere.

</DOC>
<DOC>
<DOCNO> 69929 </DOCNO>
Initial-Final State Subspace of the SU(n) Gauge Theory with Explicit


  As a part of our study on the SU(n) gauge theory with explicit gauge field
mass term this paper is devoted to form the Gupta-Bleuler subspace of the
initial-final states in the scattering process.

</DOC>
<DOC>
<DOCNO> 118943 </DOCNO>
The response of a dwarf nova disc to real mass transfer variations


  We present simulations of dwarf nova outbursts taking into account realistic
variations of the mass loss rate from the secondary. The mass transfer
variation has been derived from 20 years of visual monitoring and from X-ray
observations covering various accretion states of the discless cataclysmic
variable AM Herculis. We find that the outburst behaviour of a fictitious dwarf
nova with the same system parameters as AM Her is strongly influenced by these
variations of the mass loss rate. Depending on the mass loss rate, the disc
produces either long outbursts, a cycle of one long outburst followed by two
short outbursts, or only short outbursts. The course of the transfer rate
dominates the shape of the outbursts because the mass accreted during an
outburst cycle roughly equals the mass transferred from the secondary over the
outburst interval. Only for less than 10% of the simulated time, when the mass
transfer rate is nearly constant, the disc is in a quasi-stationary state
during which it periodically repeats the same cycle of outbursts. Consequently,
assuming that the secondary stars in non-magnetic CV's do not differ from those
in magnetic ones, our simulation indicates that probably all dwarf novae are
rarely in a stationary state and are constantly adjusting to the prevailing
value of the mass transfer rate from the secondary.

</DOC>
<DOC>
<DOCNO> 7978 </DOCNO>
Anomalous low doping phase of the Hubbard model


  We present results of a systematic Quantum-Monte-Carlo study for the
single-band Hubbard model. Thereby we evaluated single-particle spectra (PES &
IPES), two-particle spectra (spin & density correlation functions), and the
dynamical correlation function of suitably defined diagnostic operators, all as
a function of temperature and hole doping. The results allow to identify
different physical regimes. Near half-filling we find an anomalous `Hubbard-I
phase', where the band structure is, up to some minor modifications, consistent
with the Hubbard-I predictions. At lower temperatures, where the spin response
becomes sharp, additional dispersionless `bands' emerge due to the dressing of
electrons/holes with spin excitatons. We present a simple phenomenological fit
which reproduces the band structure of the insulator quantitatively. The Fermi
surface volume in the low doping phase, as derived from the single-particle
spectral function, is not consistent with the Luttinger theorem, but
qualitatively in agreement with the predictions of the Hubbard-I approximation.
The anomalous phase extends up to a hole concentration of 15%, i.e. the
underdoped region in the phase diagram of high-T_c superconductors. We also
investigate the nature of the magnetic ordering transition in the single
particle spectra. We show that the transition to an SDW-like band structure is
not accomplished by the formation of any resolvable `precursor bands', but
rather by a (spectroscopically invisible) band of spin 3/2 quasiparticles. We
discuss implications for the `remnant Fermi surface' in insulating cuprate
compounds and the shadow bands in the doped materials.

</DOC>
<DOC>
<DOCNO> 119913 </DOCNO>
Analytic Inversion of Emission Lines of Arbitrary Optical Depth for the


  We derive a method for inverting emission line profiles formed in supernova
ejecta. The derivation assumes spherical symmetry and homologous expansion
(i.e., $v(r) \propto r$), is analytic, and even takes account of occultation by
a pseudo-photosphere. Previous inversion methods have been developed which are
restricted to optically thin lines, but the particular case of homologous
expansion permits an analytic result for lines of {\it arbitrary} optical
depth. In fact, we show that the quantity that is generically retrieved is the
run of line intensity $I_\lambda$ with radius in the ejecta. This result is
quite general, and so could be applied to resonance lines, recombination lines,
etc. As a specific example, we show how to derive the run of (Sobolev) optical
depth $\tau_\lambda$ with radius in the case of a pure resonance scattering
emission line.

</DOC>
<DOC>
<DOCNO> 118071 </DOCNO>
Radio Frequency Interference


  We describe the nature of the interference challenges facing radio astronomy
in the next decade. These challenges will not be solved by regulation only,
negotiation and mitigation will become vital. There is no silver bullet for
mitigating against interference. A successful mitigation approach is most
likely to be a hierarchical or progressive approach throughout the telescope
and signal conditioning and processing systems. We summarise some of the
approaches, including adaptive systems.

</DOC>
<DOC>
<DOCNO> 9325 </DOCNO>
Conductance oscillations in mesoscopic rings: microscopic versus


  The phase of Aharonov-Bohm oscillations in mesoscopic metal rings in the
presence of a magnetic field can be modulated by application of a DC-bias
current I_DC. We address the question of how a variation of I_DC and hence of
the microscopic phases of the electronic wave functions results in the
macroscopic phase of the conductance oscillations. Whereas the first one can be
varied continuously the latter has to be quantized for a ring in two-wire
configuration by virtue of the Onsager symmetry relations. We observe a
correlation between a phase flip by +/- pi and the amplitude of the
oscillations.

</DOC>
<DOC>
<DOCNO> 118240 </DOCNO>
Characterizing the Peak in the CMB Angular Power Spectrum


  A peak has been unambiguously detected in the cosmic microwave background
(CMB) angular spectrum. Here we characterize its properties with fits to
phenomenological models. We find that the TOCO and BOOM/NA data determine the
peak location to be in the range 175--243 and 151--259 respectively (both
ranges 95% confidence) and determine the peak amplitude to be between ~70 and
90 micro Kelvin. By combining all the data, we constrain the full-width at
half-maximum to be between 180 and 250 at 95% confidence. Such a peak is
consistent with inflation-inspired flat, cold dark matter plus cosmological
constant models of structure formation with adiabatic, nearly scale-invariant
initial conditions. It is inconsistent with open and defect models.

</DOC>
<DOC>
<DOCNO> 12505 </DOCNO>
Natural linewidth analysis of d-band photoemission from Ag(110)


  We report a high-resolution angle-resolved study of photoemission linewidths
observed for Ag(110). A careful data analysis yields k$-resolved upper limits
for the inverse inelastic lifetimes of $d$-holes at the X-point of the bulk
band structure. At the upper $d$-band edge the hole-lifetime is $\tau_h \geq 22
$fs, i.e. more than one order of magnitude larger than predicted for a
free-electron gas. Following calculations for $d$-hole dynamics in Cu (I.\
Campillo et al., Phys. Rev. Lett., in press) we interpret the lifetime
enhancement by a small scattering cross-section of $d$- and $sp$-states below
the Fermi level. With increasing distance to $E_F$ the $d$-hole lifetimes get
shorter because of the rapidly increasing density of d-states and contributions
of intra-$d$-band scattering processes, but remain clearly above
free-electron-model predictions.

</DOC>
<DOC>
<DOCNO> 117754 </DOCNO>
Preheated Advection Dominated Accretion Flow


  All high temperature accretion solutions including ADAF are physically thick,
so outgoing radiation interacts with the incoming flow, sharing as much or more
resemblance with classical spherical accretion flows as with disk flows. We
examine this interaction for the popular ADAF case. We find that without
allowance for Compton preheating, a very restricted domain of ADAF solution is
permitted and with Compton preheating included a new high temperature PADAF
branch appears in the solution space. In the absence of preheating, high
temperature flows do not exist when the mass accretion rate mdot == Mdot c^2 /
L_E >~ 10^-1.5. Below this mass accretion rate, a roughly conical region around
the hole cannot sustain high temperature ions and electrons for all flows
having mdot >~ 10^-4, which may lead to a funnel possibly filled with a tenuous
hot outgoing wind. If the flow starts at large radii with the usual equilibrium
temperature ~10^4 K, the critical mass accretion rate is much lower, mdot
\~10^-3.7 above which level no self-consistent ADAF (without preheating) can
exist. However, above this critical mass accretion rate, the flow can be
self-consistently maintained at high temperature if Compton preheating is
considered. These solutions constitute a new branch of solutions as in
spherical accretion flows. High temperature PADAF flows can exist above the
critical mass accretion rate in addition to the usual cold thin disk solutions.
We also find solutions where the flow near the equatorial plane accretes
normally while the flow near the pole is overheated by Compton preheating,
possibly becoming, a polar wind, solutions which we designate WADAF.

</DOC>
<DOC>
<DOCNO> 68482 </DOCNO>
Quark and Lepton Masses from a {\boldmath $U(1)\times Z_2$} Flavor


  We show that solutions for the masses and mixings of the quarks and leptons
based on a $U(1)\times Z_2$ horizontal symmetry are possible. The seesaw
mechanism is shown to work consistently in the presence of the discrete
symmetry. The discrete symmetry results in the phenomenologically useful
suppressions of elements of the Yukawa matrices. The quark and lepton masses,
the CKM mixing angles, and the neutrino mixing angles are accomodated at the
order of magnitude level.

</DOC>
<DOC>
<DOCNO> 169696 </DOCNO>
The Persistence of Memory: Surreal Trajectories in Bohm's Theory


  In this paper I describe the history of the surreal trajectories problem and
argue that in fact it is not a problem for Bohm's theory. More specifically, I
argue that one can take the particle trajectories predicted by Bohm's theory to
be the actual trajectories that particles follow and that there is no reason to
suppose that good particle detectors are somehow fooled in the context of the
surreal trajectories experiments. Rather than showing that Bohm's theory
predicts the wrong particle trajectories or that it somehow prevents one from
making reliable measurements, such experiments ultimately reveal the special
role played by position and the fundamental incompatibility between Bohm's
theory and relativity.

</DOC>
<DOC>
<DOCNO> 122186 </DOCNO>
Mapping the Galactic Free-Free Foreground via Interstellar H-Alpha


  Recently completed H-Alpha surveys of large portions of the sky can be used
to create maps of the free-free intensity distribution at high Galactic
latitude that are independent of the spectral fits to the CMB data. This
provides an opportunity to test the accuracy of the spectral fitting procedures
and to search for other sources of Galactic forground contamination that could
be confused spectrally with the free-free, such as spinning dust grains. The
Wisconsin H-Alpha Mapper (WHAM) survey has sampled the sky north of declination
-30 deg at about one degree angular resolution and has revealed that, except
for a few isolated regions of enhanced emission, \Delta T_{ff} (30 GHz) < 30
micro-K at Galactic latitudes near 15 deg, decreasing to \Delta T_{ff} (30 GHz)
< 4 mircro-K at latitudes above 50 deg. Also in progress are H-Alpha surveys
that sample the sky at higher angular resolution.

</DOC>
<DOC>
<DOCNO> 13630 </DOCNO>
Coherent States For SU(3)


  We define coherent states for SU(3) using six bosonic creation and
annihilation operators. These coherent states are explicitly characterized by
six complex numbers with constraints. For the completely symmetric
representations (n,0) and (0,m), only three of the bosonic operators are
required. For mixed representations (n,m), all six operators are required. The
coherent states provide a resolution of identity, satisfy the continuity
property, and possess a variety of group theoretic properties. We introduce an
explicit parameterization of the group SU(3) and the corresponding integration
measure. Finally, we discuss the path integral formalism for a problem in which
the Hamiltonian is a function of SU(3) operators at each site.

</DOC>
<DOC>
<DOCNO> 40016 </DOCNO>
Higgs masses and couplings in the NMSSM


  We give the upper bounds on the masses of the lightest and second lightest CP
even Higgs bosons in the NMSSM, the MSSM extended by a gauge singlet. The
dominant two loop corrections are included. Since the coupling R of the
lightest Higgs scalar to gauge bosons can be small, we study in detail the
relation between masses and couplings of both lightest scalars. We present
upper bounds on the mass of a 'strongly' coupled Higgs (R>1/2) as a function of
lower experimental limits on the mass of a 'weakly' coupled Higgs (R<1/2). With
the help of these results, the whole parameter space of the model can be
covered.

</DOC>
<DOC>
<DOCNO> 40290 </DOCNO>
Measurement of W boson polarisations and CP-violating triple gauge


  Measurements are presented of the polarisation of W+W- boson pairs produced
in e+e- collisions, and of CP-violating WWZ and WWGamma trilinear gauge
couplings. The data were recorded by the OPAL experiment at LEP during 1998,
where a total integrated luminosity of 183 pb^-1 was obtained at a
centre-of-mass energy of 189 GeV. The measurements are performed through a spin
density matrix analysis of the W boson decay products. The fraction of W bosons
produced with longitudinal polarisation was found to be sigma_L/sigma_total =
(21.0 +- 3.3 +- 1.6)% where the first error is statistical and the second
systematic. The joint W boson pair production fractions were found to be
sigma_TT/sigma_total = (78.1 +- 9.0 +- 3.2) %, sigma_LL/sigma_total = (20.1 +-
7.2 +- 1.8) % and sigma_TL/sigma_total = (1.8 +- 14.7 +- 3.8) %. In the
CP-violating trilinear gauge coupling sector we find kappa_z = -0.20 +0.10
-0.07, g^z_4 = -0.02 +0.32 -0.33 and lambda_z = -0.18 +0.24 -0.16, where errors
include both statistical and systematic uncertainties. In each case the
coupling is determined with all other couplings set to their Standard Model
values except those related to the measured coupling via SU(2)_LxU(1)_Y
symmetry. These results are consistent with Standard Model expectations.

</DOC>
<DOC>
<DOCNO> 80683 </DOCNO>
Large-Flavor QCD on the Lattice


  We study the nature of the QCD vacuum at general number of flavors $N_F$ by
numerical simulations on the lattice. Combining the results with those of the
perturbation theory, we propose the following picture: 1) For $N_F \ge 17$,
there exists only one IR fixed point at vanishing gauge coupling, i.e., the
theory in the continuum limit is trivial. 2) For $16 \ge N_F \ge 7$, there is a
non-trivial fixed point. Therefore, the theory is non-trivial with anomalous
dimensions, however, without quark confinement. 3) For $N_F \le 6$, theories
satisfy both quark confinement and spontaneous chiral symmetry breaking in the
continuum limit.

</DOC>
<DOC>
<DOCNO> 100403 </DOCNO>
Polar Cremona transformations


  In this paper we address the following question arising from the work of P.
Etingof, D. Kazhdan and A. Polishchuk (math.AG/0003009): given a homogeneous
complex polynomial, when the rational map defined by its partials is of degree
1? We answer this question for reduced polynomials in three variables and also
for reduced polynomials in four variables which factor into the product of
linear polynomials.

</DOC>
<DOC>
<DOCNO> 101967 </DOCNO>
Renormalization Group Flow of the Two-Dimensional Hierarchical Coulomb


  We consider a quasilinear parabolic differential equation associated with the
renormalization group transformation of the two-dimensional hierarchical
Coulomb system in the limit as the size of the block L goes to 1. We show that
the initial value problem is well defined in a suitable function space and the
solution converges, as t goes to infinity, to one of the countably infinite
equilibrium solutions. The nontrivial equilibrium solution bifurcates from the
trivial one. These solutions are fully described and we provide a complete
analysis of their local and global stability for all values of inverse
temperature. Gallavotti and Nicolo's conjecture on infinite sequence of
``phases transitions'' is also addressed. Our results rule out an intermediate
phase between the plasma and the Kosterlitz-Thouless phases, at least in the
hierarchical model we consider.

</DOC>
<DOC>
<DOCNO> 84463 </DOCNO>
Notes for a Quantum Index Theorem


  We view DHR superselection sectors with finite statistics as Quantum Field
Theory analogs of elliptic operators where KMS functionals play the role of the
trace composed with the heat kernel regularization. We extend our local
holomorphic dimension formula and prove an analogue of the index theorem in the
Quantum Field Theory context. The analytic index is the Jones index, more
precisely the minimal dimension, and, on a 4-dimensional spacetime, the DHR
theorem gives the integrality of the index. We introduce the notion of
holomorphic dimension; the geometric dimension is then defined as the part of
the holomorphic dimension which is symmetric under charge conjugation. We apply
the AHKT theory of chemical potential and we extend it to the low dimensional
case, by using conformal field theory. Concerning Quantum Field Theory on
curved spacetime, the geometry of the manifold enters in the expression for the
dimension. If a quantum black hole is described by a spacetime with bifurcate
Killing horizon and sectors are localizable on the horizon, the logarithm of
the holomorphic dimension is proportional to the incremental free energy, due
to the addition of the charge, and to the inverse temperature, hence to the
surface gravity in the Hartle-Hawking KMS state. For this analysis we consider
a conformal net obtained by restricting the field to the horizon
(``holography''). Compared with our previous work on Rindler spacetime, this
result differs inasmuch as it concerns true black hole spacetimes, like the
Schwarzschild-Kruskal manifold, and pertains to the entropy of the black hole
itself, rather than of the outside system. An outlook concerns a possible
relation with supersymmetry and noncommutative geometry.

</DOC>
<DOC>
<DOCNO> 69320 </DOCNO>
Lepton Flavor Violation and Bilinear R-parity Violation


  We examine some flavor changing processes such as rare leptonic decays of the
long-lived neutral kaon, muon-electron conversion in nuclei and radiative muon
decay which are induced by the combined effects of bilinear and trilinear
R-parity violations. These processes are used to put strong constraints on
certain products of the bilinear and trilinear couplings. We also discuss the
constraints on R-parity violation from neutrino masses and compare them with
the constraints from flavor changing decay processes. Large range of parameter
space satisfying the constraints from neutrino masses can be excluded by the
flavor changing processes considered in this paper, and also vice versa.

</DOC>
<DOC>
<DOCNO> 10600 </DOCNO>
Regular dendritic patterns induced by non-local time-periodic forcing


  The dynamic response of dendritic solidification to spatially homogeneous
time-periodic forcing has been studied. Phase-field calculations performed in
two dimensions (2D) and experiments on thin (quasi 2D) liquid crystal layers
show that the frequency of dendritic side-branching can be tuned by oscillatory
pressure or heating. The sensitivity of this phenomenon to the relevant
parameters, the frequency and amplitude of the modulation, the initial
undercooling and the anisotropies of the interfacial free energy and molecule
attachment kinetics, has been explored. It has been demonstrated that besides
the side-branching mode synchronous with external forcing as emerging from the
linear Wentzel-Kramers-Brillouin analysis, modes that oscillate with higher
harmonic frequencies are also present with perceptible amplitudes.

</DOC>
<DOC>
<DOCNO> 102751 </DOCNO>
Grope cobordism of classical knots


  We explain the notion of a grope cobordism between two knots in a 3-manifold.
Each grope cobordism has a type that can be described by a rooted unitrivalent
tree. By filtering these trees in different ways, we show how the
Goussarov-Habiro approach to finite type invariants of knots is closely related
to our notion of grope cobordism. Thus our results can be viewed as a geometric
interpretation of finite type invariants.
  An interesting refinement we study are knots modulo symmetric grope cobordism
in 3-space. On one hand this theory maps onto the usual Vassiliev theory and on
the other hand it maps onto the Cochran-Orr-Teichner filtration of the knot
concordance group, via symmetric grope cobordism in 4-space. In particular, the
graded theory contains information on finite type invariants (with degree h
terms mapping to Vassiliev degree 2^h), Blanchfield forms or S-equivalence at
h=2, Casson-Gordon invariants at h=3, and for h=4 one has the new von Neumann
signatures of a knot.

</DOC>
<DOC>
<DOCNO> 13444 </DOCNO>
Who is the best connected scientist? A study of scientific coauthorship


  Using data from computer databases of scientific papers in physics,
biomedical research, and computer science, we have constructed networks of
collaboration between scientists in each of these disciplines. In these
networks two scientists are considered connected if they have coauthored one or
more papers together. We have studied many statistical properties of our
networks, including numbers of papers written by authors, numbers of authors
per paper, numbers of collaborators that scientists have, typical distance
through the network from one scientist to another, and a variety of measures of
connectedness within a network, such as closeness and betweenness. We further
argue that simple networks such as these cannot capture the variation in the
strength of collaborative ties and propose a measure of this strength based on
the number of papers coauthored by pairs of scientists, and the number of other
scientists with whom they coauthored those papers. Using a selection of our
results, we suggest a variety of possible ways to answer the question "Who is
the best connected scientist?"

</DOC>
<DOC>
<DOCNO> 69612 </DOCNO>
Quark-Gluon Plasma as a Condensate of Z(3) Wilson Lines


  Effective theories for the thermal Wilson line are constructed in an SU(N)
gauge theory at nonzero temperature. I propose that the order of the
deconfining phase transition for Z(N) Wilson lines is governed by the behavior
of SU(N) Wilson lines. In a mean field theory, the free energy in the
deconfined phase is controlled by the condensate for Z(N) Wilson lines.
Numerical simulations on the lattice, and the mean field theory for Z(3) Wilson
lines, suggest that about any finite temperature transition in QCD, the
dominant correlation length increases by a large, uniform factor, of order
five.

</DOC>
<DOC>
<DOCNO> 13703 </DOCNO>
Raman Scattering from Magnetic Excitations in coupled Spin Ladders


  We consider Raman scattering of coupled two leg spin ladders in the
Fleury-Loudon regime. We derive the dependence of the intensity with
polarization of the incoming light and temperature and discuss the effect of
interaction of the elementary excitations on the shape of the spectrum. We show
that Raman scattering spectrum is sensitive to the effective dimensionality of
the coupled ladder system, making Raman scattering useful to discriminate true
ladder systems from quasi two dimensional spin gap systems.

</DOC>
<DOC>
<DOCNO> 8650 </DOCNO>
Short, Medium and Long Range Spatial Correlations in Simple Glasses


  Local stresses and pressures always exist in glasses.
 In this letter we consider their effects on the structure and structural
correlations in simple glasses. We find that extreme values of local pressures
are related to well defined local structures. The correlations related to these
extreme stresses extend to full system size and decay as a power law with the
distance.
 This result is especially striking, since at large scales, the total density
fluctuation exhibits exponentially damped decay similar to the decay in simple
liquids. Thus at medium and large distances, the atoms with extreme values of
local pressures exhibit higher degree of correlation than the rest of the
system. These results were found for glasses with very different short range
structure, indicating their general nature.

</DOC>
<DOC>
<DOCNO> 39612 </DOCNO>
The Transverse Momentum and Total Cross Section of E+ E- Pairs in the


  The transverse momentum and total cross section of e^+e^- pairs in the
Z-boson region of 66<M_{ee}<116 GeV$/c^2$ from $p\bar{p}$ collisions at
$\sqrt{s}=1.8$ TeV are measured using 110 pb^{-1} of collisions taken by the
Collider Detector at Fermilab during 1992-1995. The total cross section is
measured to be $248 \pm 11$ pb. The differential transverse momentum cross
section is compared with calculations that match quantum chromodynamics
perturbation theory at high transverse momentum with the gluon resummation
formalism at low transverse momentum.

</DOC>
<DOC>
<DOCNO> 100980 </DOCNO>
Hyperelliptic Solutions of KdV and KP equations: Reevaluation of Baker's


  Explicit function forms of hyperelliptic solutions of Korteweg-de Vries (KdV)
and \break Kadomtsev-Petviashvili (KP) equations were constructed for a given
curve $y^2 = f(x)$ whose genus is three. This study was based upon the fact
that about one hundred years ago (Acta Math. (1903) {\bf{27}}, 135-156), H. F.
Baker essentially derived KdV hierarchy and KP equation by using bilinear
differential operator ${\bold{D}}$, identities of Pfaffians, symmetric
functions, hyperelliptic $\sigma$-function and $\wp$-functions; $\wp_{\mu \nu}
= -\partial_\mu \partial_\nu \log \sigma$ $= - ({\bold{D}}_\mu {\bold{D}}_\nu
\sigma \sigma)/2\sigma^2$. The connection between his theory and the modern
soliton theory was also discussed.

</DOC>
<DOC>
<DOCNO> 8024 </DOCNO>
Spanning Trees on Hypercubic Lattices and Non-orientable Surfaces


  We consider the problem of enumerating spanning trees on lattices.
Closed-form expressions are obtained for the spanning tree generating function
for a hypercubic lattice of size N_1 x N_2 x...x N_d in d dimensions under
free, periodic, and a combination of free and periodic boundary conditions.
Results are also obtained for a simple quartic net embedded on two
non-orientable surfaces, a Moebius strip and the Klein bottle. Our results are
based on the use of a formula expressing the spanning tree generating function
in terms of the eigenvalues of an associated tree matrix. An elementary
derivation of this formula is given.

</DOC>
<DOC>
<DOCNO> 121571 </DOCNO>
Discovery of 172-s Pulsations from a Be/X-ray Binary Candidate AX


  The results from three ASCA observations of AX J0051.6-7311 = RX J0051.9-7311
are reported. Coherent pulsations with a barycentric period of 172.40 +/- 0.03
s were discovered in the third observation, with an exceptionally long exposure
time of ~177 ks. The X-ray spectrum was found to remain unchanged through these
observations, with a photon index of ~0.9. Energy-resolved pulse profiles in
the third observation reveal that the pulsations are mostly due to photons with
an energy above ~2 keV. Archival data of ROSAT and Einstein indicate that AX
J0051.6-7311 exhibits a flux variation having a factor ~> 20.

</DOC>
<DOC>
<DOCNO> 178848 </DOCNO>
Phi^{zero}-N Bound State


  We show that the QCD van der Waals attractive potential is strong enough to
bind a $\phi^{0}$ meson onto a nucleon inside a nucleus to form a bound state.
The direct experimental signature for such an exotic state is proposed in the
case of subthreshold $\phi^{0}$ meson photoproduction from nuclear targets. The
production rate is estimated and such an experiment is found to be feasible at
the Jefferson Laboratory.

</DOC>
<DOC>
<DOCNO> 117707 </DOCNO>
Starburst-driven galactic winds: I. Energetics and intrinsic X-ray


  We have performed an extensive hydrodynamical parameter study of
starburst-driven galactic winds, motivated by the latest observation data on
the best-studied starburst galaxy M82. We study how the wind dynamics,
morphology and X-ray emission depend on the host galaxy's ISM distribution,
starburst star formation history and strength, and presence and distribution of
mass-loading by dense clouds. We find that the soft X-ray emission from
galactic winds comes from low filling factor (ff < 2 per cent) gas, which
contains only a small fraction (f < 10 per cent) of the mass and energy of the
wind, irrespective of whether the wind models are strongly mass-loaded or not.
X-ray observations of galactic winds therefore do not directly probe the gas
that contains the majority of the energy, mass or metal-enriched gas in the
outflow. The soft X-ray emission comes from gas at a wide range different
temperatures and densities. Estimates of the physical properties of the hot gas
in starburst galaxies, based on fitting the standard simple spectral models to
existing X-ray spectra, should therefore be treated with extreme suspicion. The
majority of the thermal and kinetic energy of these winds is in a volume
filling hot, T approx 10^7 K, component which is extremely difficult to probe
observationally due to its low density and hence low emissivity. Most of the
total energy is in the kinetic energy of this hot gas, a factor which must be
taken into account when attempting to constrain wind energetics
observationally. We also find that galactic winds are efficient at transporting
large amounts of energy out of the host galaxy, in contrast to their
inefficiency at transporting mass out of star-forming galaxies. (Abridged)

</DOC>
<DOC>
<DOCNO> 11290 </DOCNO>
High Magnetic Field Behaviour of the Triangular Lattice Antiferromagnet,


  The high magnetic field behaviour of the triangular lattice antiferromagnet
CuFeO_2 is studied using single crystal neutron diffraction measurements in a
field of up to 14.5 T and also by magnetisation measurements in a field of up
to 12 T. At low temperature, two well-defined first order magnetic phase
transitions are found in this range of applied magnetic field (H // c): at
H_c1=7.6(3)/7.1(3) T and H_c2=13.2(1)/12.7(1) T when ramping the field up/down.
In a field above H_c2 the magnetic Bragg peaks show unusual history dependence.
In zero field T_N1=14.2(1) K separates a high temperature paramagnetic and an
intermediate incommensurate structure, while T_N2=11.1(3) K divides an
incommensurate phase from the low-temperature 4-sublattice ground state. The
ordering temperature T_N1 is found to be almost field independent, while T_N2
decreases noticeably in applied field. The magnetic phase diagram is discussed
in terms of the interactions between an applied magnetic field and the highly
frustrated magnetic structure of CuFeO_2

</DOC>
<DOC>
<DOCNO> 121720 </DOCNO>
The Expansion of the X-ray Remnant of Tycho's Supernova (SN1572)


  Two ROSAT high resolution images separated by nearly five years have been
used to determine the expansion of the X-ray remnant of Tycho's supernova
(SN1572). The current expansion rate averaged over the entire remnant is
$0.124\pm0.011$ % per yr, which, when combined with the known age of the
remnant, determines the mean expansion parameter $m$, defined as $R\propto
t^m$, to be $0.54\pm0.05$. There are significant radial and azimuthal
variations of the X-ray expansion rate. The radial expansion in particular
shows highly significant evidence for the more rapid expansion of the forward
blast wave as compared to the reverse-shocked ejecta, an effect that has not
been seen previously. The expansion parameter varies from $m=0.71\pm0.06$ at
the outermost edge of Tycho's supernova remnant (SNR) to a value of
$m=0.34\pm0.10$ on the inside edge of the bright rim of emission. These values
are consistent with the rates expected for a remnant with constant density
ejecta evolving into a uniform interstellar medium during the ejecta-dominated
phase of evolution. Based on the size, age, and X-ray expansion rates, I obtain
values for the explosion energy and ambient density of $E\approx 4-5\times
10^{50} \rm ergs$ and $n_0 \approx 0.35-0.45 \rm cm^{-3}$. As is also the case
for Cas A and Kepler's SNR, the X-ray expansion rate of Tycho's SNR appears to
be significantly higher than the radio expansion rate. In the case of Tycho's
SNR, however, the difference between radio and X-ray expansion rates is clearly
associated with the motion of the forward shock.

</DOC>
<DOC>
<DOCNO> 85524 </DOCNO>
The First Search for Gravitational Waves from Inspiraling Compact


  We analyzed 6 hours of data from the TAMA300 detector by matched filtering,
searching for gravitational waves from inspiraling compact binaries. We
incorporated a two-step hierarchical search strategy in matched filtering. We
obtained an upper limit of 0.59/hour (C.L.=90%) on the event rate of inspirals
of compact binaries with mass between 0.3M_solar and 10M_solar and with
signal-to-noise ratio greater than 7.2. The distance of 1.4M_solar (0.5M_solar)
binaries which produce the signal-to-noise ratio 7.2 was estimated to be 6.2kpc
(2.9kpc) when the position of the source on the sky and the inclination angle
of the binaries were optimal.

</DOC>
<DOC>
<DOCNO> 67910 </DOCNO>
Predictions on $B \to \pi \bar{l} \nu_l$, $D \to \pi \bar{l} \nu_l$ and


  The $f^+$ form factors of the $B\to \pi$, $D\to \pi$ and $D\to K$ transitions
are calculated from QCD light-cone sum rules (LCSR) and used to predict the
widths and differential distributions of the exclusive semileptonic decays
$B\to \pi \bar{l}\nu_l$, $D \to\pi \bar{l}\nu_l$ and $D \to K \bar{l}\nu_l$,
where $l=e,\mu$. The current theoretical uncertainties are estimated. The LCSR
results are found to agree with the results of lattice QCD calculations and
with experimental data on exclusive semileptonic D decays. Comparison of the
LCSR prediction on $B\to \pi \bar{l} \nu_l$ with the CLEO measurement yields a
value of |V_{ub}| in agreement with other determinations.

</DOC>
<DOC>
<DOCNO> 102711 </DOCNO>
Finsleroids Reflect Future-Past Asymmetry of Space-Time


  The Finslerian extension of the Euclidean metric is proposed and studied
under rigorous conditions that the associated indicatrix is regular and convex.
The relativistic pseudo-Euclidean metric is extended, too. The extensions show
distinct violation of the $T-$parity, so that the future-past asymmetry of the
physical world can stem from the $T-$asymmetry of the Finslerian indicatrix.
Indeed the idea should compel much attention of physicists.

</DOC>
<DOC>
<DOCNO> 68193 </DOCNO>
Do strange stars exist in the Universe?


  Definitely, an affirmative answer to this question would have implications of
fundamental importance for astrophysics (a new class of compact stars), and for
the physics of strong interactions (deconfined phase of quark matter, and
strange matter hypothesis). In the present work, we use observational data for
the newly discovered millisecond X-ray pulsar SAX J1808.4-3658 and for the
atoll source 4U 1728-34 to constrain the radius of the underlying compact
stars. Comparing the mass-radius relation of these two compact stars with
theoretical models for both neutron stars and strange stars, we argue that a
strange star model is more consistent with SAX J1808.4-3658 and 4U 1728-34, and
suggest that they are likely strange star candidates.

</DOC>
<DOC>
<DOCNO> 10045 </DOCNO>
Hierarchical organization of cities and nations


  Universality in the behavior of complex systems often reveals itself in the
form of scale-invariant distributions that are essentially independent of the
details of the microscopic dynamics. A representative paradigm of complex
behavior in nature is cooperative evolution. The interaction of individuals
gives rise to a wide variety of collective phenomena that strongly differ from
individual dynamics---such as demographic evolution, cultural and technological
development, and economic activity. A striking example of such cooperative
phenomena is the formation of urban aggregates which, in turn, can be
considered to cooperate in giving rise to nations. We find that population and
area distributions of nations follow an inverse power-law behavior, as is known
for cities. The exponents, however, are radically different in the two cases
($\mu \approx 1$ for nations, $\mu \approx 2$ for cities). We interpret these
findings by developing growth models for cities and for nations related to
basic properties of partition of the plane. These models allow one to
understand the empirical findings without resort to the introduction of complex
socio-economic factors.

</DOC>
<DOC>
<DOCNO> 170564 </DOCNO>
Quantum Coherence in a Single Ion due to strong Excitation of a


  We consider pump-probe spectroscopy of a single ion with a highly metastable
(probe) clock transition which is monitored by using the quantum jump
technique. For a weak clock laser we obtain the well known Autler-Townes
splitting. For stronger powers of the clock laser we demonstrate the transition
to a new regime. The two regimes are distinguished by the transition of two
complex eigenvalues to purely imaginary ones which can be very different in
magnitude. The transition is controlled by the power of the clock laser. For
pump on resonance we present simple analytical expressions for various
linewidths and line positions.

</DOC>
<DOC>
<DOCNO> 71316 </DOCNO>
From effective actions to actual effects in QED


  The construction of low-energy effective actions in QED for several types of
external conditions is reviewed. Emphasis is put on the application of these
effective actions to a variety of physical effects which represent a
manifestation of vacuum polarization. Soft-photon interactions with external
electromagnetic fields and/or a heat bath are described, pair production at
finite temperature is discussed, and finally a glance at photon-neutrino
interactions is provided.

</DOC>
<DOC>
<DOCNO> 68950 </DOCNO>
Fermion Electric Dipole Moments in Supersymmetric Models with R-parity


  We analyze the electron and neutron electric dipole moments induced by
R-parity violating interactions in supersymmetric models. It is pointed out
that dominant contributions can come from one-loop diagrams involving both the
bilinear and trilinear R-parity odd couplings, leading to somewhat severe
constraints on the products of those couplings.

</DOC>
<DOC>
<DOCNO> 7857 </DOCNO>
Learning short-option valuation in the presence of rare events


  We present a neural-network valuation of financial derivatives in the case of
fat-tailed underlying asset returns. A two-layer perceptron is trained on
simulated prices taking into account the well-known effect of volatility smile.
The prices of the underlier are generated using fractional calculus algorithms,
and option prices are computed by means of the Bouchaud-Potters formula. This
learning scheme is tested on market data; the results show a very good
agreement between perceptron option prices and real market ones.

</DOC>
<DOC>
<DOCNO> 100154 </DOCNO>
Matrix Theory over the Complex Quaternion Algebra


  We present in this paper some fundamental tools for developing matrix
analysis over the complex quaternion algebra. As applications, we consider
generalized inverses, eigenvalues and eigenvectors, similarity, determinants of
complex quaternion matrices, and so on.

</DOC>
<DOC>
<DOCNO> 8448 </DOCNO>
Energy level dynamics in systems with weakly multifractal eigenstates:


  It is shown that the parametric spectral statistics in the critical random
matrix ensemble with multifractal eigenvector statistics are identical to the
statistics of correlated 1D fermions at finite temperatures. For weak
multifractality the effective temperature of fictitious 1D fermions is
proportional to (1-d_{n})/n, where d_{n} is the fractal dimension found from
the n-th moment of inverse participation ratio. For large energy and parameter
separations the fictitious fermions are described by the Luttinger liquid model
which follows from the Calogero-Sutherland model. The low-temperature
asymptotic form of the two-point equal-parameter spectral correlation function
is found for all energy separations and its relevance for the low temperature
equal-time density correlations in the Calogero-Sutherland model is
conjectured.

</DOC>
<DOC>
<DOCNO> 69470 </DOCNO>
Quark-Gluon Plasma Fireball


  Lattice-QCD results provide an opportunity to model, and extrapolate to
finite baryon density, the properties of the quark-gluon plasma (QGP). Upon
fixing the scale of the thermal coupling constant and vacuum energy to the
lattice data, the properties of resulting QGP equations of state (EoS) are
developed. We show that the physical properties of the dense matter fireball
formed in heavy ion collision experiments at CERN-SPS are well described by the
QGP-EoS we presented. We also estimate the properties of the fireball formed in
early stages of nuclear collision, and argue that QGP formation must be
expected down to 40A GeV in central Pb--Pb interactions.

</DOC>
<DOC>
<DOCNO> 84412 </DOCNO>
Electrodynamics of accelerated charges or Why electron does not radiate


  It is shown, that the radiation of the charge, moving with uniform
acceleration or uniformly moving round a circle and also freely moving in a
gravitational field, contradicts the principle of equivalence. It is also
shown, that the interaction of the charges, moving with uniform acceleration or
uniformly circling, which has been calculated within the framework of classical
electrodynamics, leads to the violation of laws of conservation of energy,
impulse and angular momentum. We have offered a method in which way to conform
electrodynamics to the principle of equivalence. So in the electrodynamics,
which has been conformed in such a way, all the mentioned violations of the
laws of conservation are automatically removed and the stability of
Rutherford's atom is explained. It is shown that the changes, which we have
brought into the electrodynamics, do not contradict the results of experiments.

</DOC>
<DOC>
<DOCNO> 13870 </DOCNO>
A renormalized expression for the turbulent energy dissipation rate


  Conditional elimination of degrees of freedom is shown to lead to an exact
expression for the rate of turbulent energy dissipation in terms of a
renormalized viscosity and a correction. The correction is neglected on the
basis of a previous hypothesis [W.D. McComb and C. Johnston, J.Phys.A v33 L15
(2000)] that there is a range of parameters for which a quasi-stochastic
estimate is a good approximation to the exact conditional average. This
hypothesis was tested by a perturbative calculation to second order in the
local Reynolds number, and the Kolmogorov prefactor (taken as a measure of the
renormalized dissipation rate) was found to reach a fixed point which was
insensitive to initial values of the kinematic viscosity and to values of the
spatial rescaling factor h in the range 0.4 <= h <= 0.8.

</DOC>
<DOC>
<DOCNO> 84153 </DOCNO>
Gravitational waves emitted by extrasolar planetary systems


  In this paper we consider the Extra-solar Planetary Systems recently
discovered in our Galaxy as potential sources of gravitational waves. We
estimate the frequency and characteristic amplitude of the radiation they emit
due to the orbital motion, using the quadrupole formalism. In addition, we
check whether the conditions needed for the resonant excitation of the f- and
g-modes of the central star can be fulfilled. By a Roche-lobe analysis, we show
that there could exist systems in which the low-order g-modes could be excited,
although this does not happen in the systems discovered up to now.

</DOC>
<DOC>
<DOCNO> 100725 </DOCNO>
From symmetries of the modular tower of genus zero real stable curves to


  We build actions of Thompson group V (related to the Cantor set) and of the
so-called "spheromorphism" group of Neretin, on "towers" of moduli spaces of
genus zero real stable curves. The latter consist of inductive limits of spaces
which are the real parts of the Grothendieck-Knudsen compactification of the
usual moduli spaces of punctured Riemann spheres. By a result of M. Davis, T.
Januszkiewicz and R. Scott, these spaces are aspherical cubical complexes,
whose fundamental groups, the "pure quasi-braid groups", are some analogues of
the classical pure braid groups. By lifting the actions of Thompson and Neretin
groups to the universal covers of the towers, we get new extensions of both
groups by an infinite pure quasi-braid group, and construct what we call an
"Euler class" for Neretin group, justifying the terminology by exhibiting an
Euler-type cocycle. Further, after introducing the infinite (non-pure)
quasi-braid group, we show that both infinite (non-pure and pure) quasi-braid
groups provide new examples of groups whose classifying spaces, after
plus-construction, are loop spaces.

</DOC>
<DOC>
<DOCNO> 10124 </DOCNO>
Curved dilatonic brane-worlds and the cosmological constant problem


  We construct a model for dilatonic brane worlds with constant curvature on
the brane, i.e. a non-zero four-dimensional cosmological constant, given in
function of the dilaton coupling and the cosmological constant of the bulk. We
compare this family of solutions to other known dilatonic domain wall solutions
and apply a self-tunning mechanism to check the stability of our solutions
under quantum fluctuations living on the brane.

</DOC>
<DOC>
<DOCNO> 122928 </DOCNO>
Gas motions in the plane of the spiral galaxy NGC 3631


  The velocity field of the nearly face-on galaxy NGC 3631, derived from
observations in the H alpha line and the HI radio line, is analysed to study
perturbations related to the spiral structure of the galaxy. We confirm our
previous conclusion that the line-of-sight velocity field gives evidence of the
wave nature of the observed two-armed spiral structure. Fourier analysis of the
observed velocity field is used to determine the location of corotation of the
spiral structure of this galaxy, and the radius of corotation R_c is found to
be about 42 arcsec, or 3.2 kpc. The vector velocity field of the gas in the
plane of the disc is restored, and taking into account that we previously
investigated vertical motions, we now have a full 3D gaseous velocity field of
the galaxy. We show clear evidence of the existence of two anticyclonic and
four cyclonic vortices near corotation in a frame of reference rotating with
the spiral pattern. The centres of the anticyclones lie between the observed
spiral arms. The cyclones lie close to the observed spirals, but their centres
are shifted from the maxima in brightness.

</DOC>
<DOC>
<DOCNO> 121045 </DOCNO>
Stellar Populations, Bars and Secular Evolution in Late-Type Galaxies


  We have done a robust statistical analysis of UBV color profiles of 257 Sbc
barred and unbarred galaxies. We found that there is an excess of barred
galaxies among the objects with null or positive (bluish inward) color
gradients, which seems to indicate that bars act as a mechanism of
homogenization of the stellar population along galaxies. Moreover, the
relationship found between total and bulge colors shows that, in the process of
homogenization, the stellar population of bulges are getting bluer, whereas the
total color of galaxies remains the same. These characteristics are expected in
a secular evolutionary scenario, and seem incompatible with both the monolithic
and the hierarchical scenarios for spiral galaxy formation.

</DOC>
<DOC>
<DOCNO> 119792 </DOCNO>
The White Dwarf Cooling Age of the Open Cluster NGC 2420


  We have used deep HST WFPC2 observations of two fields in NGC 2420 to produce
a cluster CMD down to V = 27. After imposing morphological selection criteria
we find eight candidate white dwarfs in NGC 2420. Our completeness estimates
indicate that we have found the terminus of the WD cooling sequence. We argue
that the cluster distance modulus is likely to be close to 12.10 with E(B-V) =
0.04. With these parameters we find a white dwarf cooling age for NGC 2420 of
2.0 +- 0.20 (1 sigma) Gyrs. The 0.20 Gyr uncertainty includes errors in the
photometry, sequence fitting, precursor time scales, and theoretical white
dwarf cooling time scales. Comparing the cluster white dwarf cooling age to
ages derived from stellar isochrone fitting we find a preference for ages
derived from models incorporating convective overshoot.

</DOC>
<DOC>
<DOCNO> 13501 </DOCNO>
Strings from Logic


  What are strings made of? The possibility is discussed that strings are
purely mathematical objects, made of logical axioms. More precisely, proofs in
simple logical calculi are represented by graphs that can be interpreted as the
Feynman diagrams of certain large-N field theories. Each vertex represents an
axiom. Strings arise, because these large-N theories are dual to string
theories. These ``logical quantum field theories'' map theorems into the space
of functions of two parameters: N and the coupling constant. Undecidable
theorems might be related to nonperturbative field theory effects.

</DOC>
<DOC>
<DOCNO> 99973 </DOCNO>
Weak reflection at the successor of singular


  The notion of stationary reflection is one of the most important notions of
combinatorial set theory. We investigate weak reflection, which is, as the name
suggests, a weak version of stationary reflection. This sort of reflection was
introduced in [DjSh:545] (math.LO/9601219), where it was shown that weak
reflection has applications to various guessing principles, in the sense that
if there is no weak reflection, than a guessing principle holds, and an
application dealing with the saturation of normal filters. Further
investigations of weak reflection were carried in [CDSh:571] (math.LO/9504221)
and [CuSh:596] (math.LO/9703219). While various ZFC restrictions on the one
hand, and independence results on the other, were discovered about the weak
reflection, the question of the relative consistency of the existence of a
regular cardinal kappa such that the first cardinal weakly reflecting at kappa
is a successor of singular, remained open. This paper answers that question by
proving that (modulo large cardinal assumptions close to 2-hugeness) that there
indeed can be such a cardinal kappa.

</DOC>
<DOC>
<DOCNO> 13486 </DOCNO>
Temperature Dependence of Spin Correlation and Charge Dynamics in the


  We examine the temperature dependence of the electronic states in the stripe
phase of high-Tc cuprates by using the t-J model with a potential that
stabilizes vertical charge stripes. Charge and spin-correlation functions and
optical conductivity are calculated by using finite-temperature Lanczos method.
At zero temperature, the antiferromagnetic correlation between a spin in a
charge stripe and that in a spin domain adjacent to the stripe is weak, since
the charge stripe and the spin domain are almost separated. With increasing
temperature, the correlation increases and then decreases toward high
temperature. This is in contrast to other correlations that decrease
monotonically. From the examination of the charge dynamics, we find that this
anomalous temperature dependence of the correlation is the consequence of a
crossover from one-dimensional electronic states to two-dimensional ones.

</DOC>
<DOC>
<DOCNO> 170810 </DOCNO>
A Generalization of Grover's Algorithm


  We investigate the necessary and sufficient conditions in order that a
unitary operator can amplify a pre-assigned component relative to a particular
basis of a generic vector at the expense of the other components. This leads to
a general method which allows, given a vector and one of its components we want
to amplify, to choose the optimal unitary operator which realizes that goal.
Grover's quantum algorithm is shown to be a particular case of our general
method. However the general structure of the unitary we find is remarkably
similar to that of Grover's one: a sign flip of one component combined with a
reflection with respect to a vector. In Grover's case this vector is fixed; in
our case it depends on a parameter and this allows optimization.

</DOC>
<DOC>
<DOCNO> 12843 </DOCNO>
Collective enhancement and suppression in Bose-Einstein condensates


  The coherent and collective nature of Bose-Einstein condensate can enhance or
suppress physical processes. Bosonic stimulation enhances scattering in already
occupied states which leads to atom amplification, and the suppression of
dissipation leads to superfluidity. In this paper, we review several
experiments where suppression and enhancement have been observed and discuss
the common roots of and differences between these phenomena.

</DOC>
<DOC>
<DOCNO> 69753 </DOCNO>
Testing for New Couplings in Top Quark Decay


  Tests of the Lorentz structure of t --> W b decay will be carried out at the
Tevatron, and later at the LHC and at a NLC. To quantitatively assay future
measurements of competing observables, we consider the (V-A) coupling values of
the helicity decay parameters versus "(V-A) + Single Additional Lorentz
Structures". Three phase-type ambiguities exist, but measurement of the sign of
the large interference between the W boson longitudinal/transverse amplitudes
could exclude the two due dynamically to additional (S+P) and (f_M + f_E)
couplings. Sizable T-violation signatures can occur for low-effective mass
scales, < 320 GeV, but in most cases can be more simply excluded by 10%
precision measurement of the probabilities P(W_L) and P(b_L). Signatures for
the presence of T-violation associated with the dynamical phase-type
ambiguities, CP-violation signatures, and Lambda_b polarimetry are also
discussed.

</DOC>
<DOC>
<DOCNO> 101849 </DOCNO>
Quasi-isometries between non-locally-finite graphs and structure trees


  We prove several criteria for quasi-isometry between non-locally-finite
graphs and their structure trees. Results of M\"oller in \cite{moeller92ends2}
for locally finite and transitive graphs are generalized. We also give a
criterion which describes quasi-isometry by how edge-ends are split up by the
cuts of a structure tree.

</DOC>
<DOC>
<DOCNO> 80870 </DOCNO>
Vortex structure of the vacuum and confinement


  We discuss the recently published numerical computations of the vortex free
energy. They dramatically demonstrate that the excitation probability for a
sufficiently thick vortex approaches unity at large beta, i.e. that thick
vortices `condense' in the vacuum. This is known to imply confinement. An
analytical approach for exploring this phenomenon is also outlined.

</DOC>
<DOC>
<DOCNO> 12943 </DOCNO>
Topological relaxation of entangled flux lattices: Single vs collective


  A symbolic language allowing to solve statistical problems for the systems
with nonabelian braid-like topology in 2+1 dimensions is developed. The
approach is based on the similarity between growing braid and "heap of colored
pieces". As an application, the problem of a vortex glass transition in
high-T_c superconductors is re-examined on microscopic level

</DOC>
<DOC>
<DOCNO> 7893 </DOCNO>
Pinning of quantized vortices in helium drop by dopant atoms and


  Using a density functional method, we investigate the properties of liquid
4He droplets doped with atoms (Ne and Xe) and molecules (SF_6 and HCN). We
consider the case of droplets having a quantized vortex pinned to the dopant. A
liquid drop formula is proposed that accurately describes the total energy of
the complex and allows one to extrapolate the density functional results to
large N. For a given impurity, we find that the formation of a
dopant+vortex+4He_N complex is energetically favored below a critical size
N_cr. Our result support the possibility to observe quantized vortices in
helium droplets by means of spectroscopic techniques.

</DOC>
<DOC>
<DOCNO> 68409 </DOCNO>
A General Classification of Three-Neutrino Models and U_e3


  A classification of models with three light neutrinos is given. This
classification includes virtually all of the three-neutrino models proposed in
the last few years, of which there are approximately one hundred. The essential
ideas, attractive features, and characteristic problems of the different
classes of model are discussed. The classification is based principally on how
the large \nu_{\mu} - \nu_{\tau} mixing is obtained. A general discussion of
the mixing parameter U_{e3} is then given, showing what values are to be
expected for it in each type of model.

</DOC>
<DOC>
<DOCNO> 40555 </DOCNO>
Importance of Future Hyperon Beta Decay Experiments


  Recent results from the KTeV experiment at Fermilab using $\Xi^0$ hyperons
have enabled a great leap in improving our understanding of elementary particle
physics, especially with the first form-factor measurement from the
semi-leptonic decay $\Xi^0 \to \Sigma^+ e^- \bar{\nu}$. This decay is a test of
whether the standard model contains all of the needed parameters to fully
describe hyperon beta decay. It was observed for the first time only in 1997
even though its importance had been explicitly stated in 1961 by the early
theories of the standard model as formulated by N. Cabibbo. We have the ability
to improve this measurement substantially by making the definitive form-factor
measurement with a sample of 30,000 such decays from a forthcoming experiment,
which will either show or rule out the existence any additional second class
weak currents, an obviously important measurement allowing particle physics to
finally put this question to rest. We also have the ability to make a
measurement of hyperon compositeness by measuring the charged $\Sigma^{\pm}$
beta decay into $\Lambda^0$, and in addition to search for mass coupling terms
in hyperon beta decays where the muon replaces the electron, important for
determining the $g_3$ and $f_3$ form-factors. These are the important questions
to answer in studying strange baryon decays, and are reviewed in this article.

</DOC>
<DOC>
<DOCNO> 119849 </DOCNO>
On non-Gaussianity in the Cosmic Microwave Background


  We consider a cosmological model with non-Gaussian initial perturbations,
which in principle could be generated in non-standard inflationary scenarios
with two or more scalar fields. In particular we focus our attention on the
model proposed by Linde & Mukhanov (1997) perturbations are quadratic in a
Gaussian field. These perturbations, if they exist, have to be observable as a
non-Gaussian distribution of the CMB signal on the sky. In order to efficiently
pick up the non-Gaussian signal in CMB maps of degree resolution, one can use
Minkowski Functionals and peak statistics. Our paper contains the theoretical
predictions of the properties for Minkowski Functionals and distributions of
peaks of the CMB anisotropy in the model with "squared" Gaussian statistics.
Likelihood comparison of the four-year COBE DMR data to this non-Gaussian model
and the standard Gaussian model does not select any of them as most likely. We
also suggest an efficient algorithm for fast simulation of CMB maps on the
whole sky. Using a cylindrical partition of the sphere, we rewrite the
spherical harmonics analysis as a Fourier transform in flat space, which makes
the problem accessible to numerically advantageous FFT methods.

</DOC>
<DOC>
<DOCNO> 152557 </DOCNO>
(2,0) Chern-Simons Supergravity Plus Matter Near the Boundary of AdS_3


  We examine the boundary behaviour of the gauged N=(2,0) supergravity in D=3
coupled to an arbitrary number of scalar supermultiplets which parametrize a
Kahler manifold. In addition to the gravitational coupling constant, the model
depends on two parameters, namely the cosmological constant and the size of the
Kahler manifold. It is shown that regular and irregular boundary conditions can
be imposed on the matter fields depending on the size of the sigma model
manifold. It is also shown that the super AdS transformations in the bulk
produce the transformations of the N=(2,0) conformal supergravity and scalar
multiplets on the boundary, containing fields with nonvanishing Weyl weights
determined by the ratio of the sigma model and the gravitational coupling
constants. Various types of (2,0) superconformal multiplets are found on the
boundary and in one case the superconformal symmetry is shown to be realized in
an unconventional way.

</DOC>
<DOC>
<DOCNO> 80792 </DOCNO>
A study of center vortices in SU(2) and SU(3) gauge theories


  We show how center vortices and Abelian monopoles both appear as local gauge
ambiguities in the Laplacian Center gauge. Numerical results, for SU(2) and
SU(3), support the view that the string tension obtained in the
center-projected theory matches the full string tension when the continuum
limit is taken.

</DOC>
<DOC>
<DOCNO> 68160 </DOCNO>
Penguins and Mixing Dependent CP Violation


  Constraints on angles of Unitarity triangle are reviewed, and in particular
constraint on $\gamma$ from limit on $\Delta m_s$ is emphasized. Effects of
penguin diagram on measurement of $\beta$ and $\alpha$ are then reviewed. New
measurements on $B \to \pi^+\pi^-$ in QCD improved factorization approximation
suggest large penguin effects. It is possible to estimate the error in
measurement of $\alpha$ as a function of $\gamma$ for different $|V_{ub}
/V_{cb}|$ values.

</DOC>
<DOC>
<DOCNO> 12146 </DOCNO>
Comment on: High-Pressure Elasticity of alpha-Quartz: Instability and


  We comment on the stability analysis of alpha-quartz under pressure by
Gregoryanz et al., Phys. Rev. Lett. 84, 3117 (2000). The proper stability
criterion for solids under pressure has to be formulated in terms of Birch
coefficients rather than in terms of elastic constants. We show that the
fictitious (extrapolated) stable phase of alpha-quartz above a pressure of 22
GPa is much smaller than anticipated by Gregoryanz et al.

</DOC>
<DOC>
<DOCNO> 10314 </DOCNO>
Marketing Percolation


  A percolation model is presented, with computer simulations for
illustrations, to show how the sales of a new product may penetrate the
consumer market. We review the traditional approach in the marketing
literature, which is based on differential or difference equations similar to
the logistic equation (Bass 1969). This mean field approach is contrasted with
the discrete percolation on a lattice, with simulations of "social percolation"
(Solomon et al 2000) in two to five dimensions giving power laws instead of
exponential growth, and strong fluctuations right at the percolation threshold.

</DOC>
<DOC>
<DOCNO> 170727 </DOCNO>
Chaotic atomic population oscillations between two coupled Bose-Einstein


  We have investigated the chaotic atomic population oscillations between two
coupled Bose-Einstein condensates (BEC) with time-dependent asymmetric trap
potential. In the perturbative regime, the population oscillations can be
described by the Duffing equation, and the chaotic oscillations near the
separatrix solution are analyzed. The sufficient-necessary conditions for
stable oscillations depend on the physical parameters and initial conditions
sensitively. The first-order necessary condition indicates that the Melnikov
function is equal to zero, so the stable oscillations are Melnikov chaotic. For
the ordinary parameters and initial conditions, the chaotic dynamics is
simulated with numerical calculation. If the damping is absent, with the
increasing of the trap asymmetry, the regular oscillations become chaotic
gradually, the corresponding stroboscopic Poincare sections (SPS) vary from a
single island to more islands, and then the chaotic sea. For the completely
chaotic oscillations, the long-term localization disappears and the short-term
localization can be changed from one of the BECs to the other through the route
of Rabi oscillation. When there exists damping, the stationary chaos
disappears, the transient chaos is a common phenomenon before regular stable
frequency locked oscillations. And proper damping can keep localization
long-lived.

</DOC>
<DOC>
<DOCNO> 170457 </DOCNO>
Information Tradeoff Relations for Finite-Strength Quantum Measurements


  In this paper we give a new way to quantify the folklore notion that quantum
measurements bring a disturbance to the system being measured. We consider two
observers who initially assign identical mixed-state density operators to a
two-state quantum system. The question we address is to what extent one
observer can, by measurement, increase the purity of his density operator
without affecting the purity of the other observer's. If there were no
restrictions on the first observer's measurements, then he could carry this out
trivially by measuring the initial density operator's eigenbasis. If, however,
the allowed measurements are those of finite strength---i.e., those
measurements strictly within the interior of the convex set of all
measurements---then the issue becomes significantly more complex. We find that
for a large class of such measurements the first observer's purity increases
the most precisely when there is some loss of purity for the second observer.
More generally the tradeoff between the two purities, when it exists, forms a
monotonic relation. This tradeoff has potential application to quantum state
control and feedback.

</DOC>
<DOC>
<DOCNO> 150375 </DOCNO>
Electromagnetic dipole radiation of oscillating D-branes


  I emphasize analogy between Dp-branes in string theories and solitons in
gauge theories comparing their common properties and showing differences. We
will show that for certain excitations of the string/D3-brane system Neumann
boundary conditions emerge from the Born-Infeld dynamics. The excitations which
are coming down the string with a polarization along a direction parallel to
the brane are almost completely reflected. For the wavelengths much larger than
the string scale only a small fraction of the energy escapes in the form of
dipole radiation. The physical interpretation is that a string attached to the
3-brane manifests itself as an electric charge, and waves on the string cause
the end point of the string to freely oscillate and produce electromagnetic
dipole radiation in the asymptotic outer region. The magnitude of emitted power
is in fact exactly equal to the one given by Thompson formula in ordinary
electrodynamics.

</DOC>
<DOC>
<DOCNO> 10372 </DOCNO>
Instability of the symmetric Couette-flow in a granular gas:


  Submission removed because authors erroneously made duplicate submission of
cond-mat/0006066.

</DOC>
<DOC>
<DOCNO> 69802 </DOCNO>
Casimir scaling of SU(3) static potentials


  Potentials between static colour sources in eight different representations
are computed in four dimensional SU(3) gauge theory. The simulations have been
performed with the Wilson action on anisotropic lattices where the renormalised
anisotropies have been determined non-perturbatively. After an extrapolation to
the continuum limit we are able to exclude any violations of the Casimir
scaling hypothesis that exceed 5% for source separations of up to 1 fm.

</DOC>
<DOC>
<DOCNO> 170398 </DOCNO>
Decoherence, pointer engineering and quantum state protection


  We present a proposal for protecting states against decoherence, based on the
engineering of pointer states. We apply this procedure to the vibrational
motion of a trapped ion, and show how to protect qubits, squeezed states,
approximate phase eigenstates and superpositions of coherent states.

</DOC>
<DOC>
<DOCNO> 100236 </DOCNO>
Trivalent Graphs and Solitons


  It is shown that the fourth order real self-adjoint difference operator on
the Tivalent Tree admits nontrivial deformations preserving one energy level
and therefore defines a nontrinial hierarhy of the completely integrable
nonlinear systems representible through the ''L-A-B-triple''. The Laplace
transformations for these operators are also constructed. Nothing like that
exists for the second order difference operators on this tree.

</DOC>
<DOC>
<DOCNO> 100984 </DOCNO>
Simultaneous decomposition of two states


  Simultaneous decompositions of a pair of states into pure ones are examined.
There are privileged decompositions which are distinguished from all the other
ones.

</DOC>
<DOC>
<DOCNO> 118896 </DOCNO>
Exploration of the BaSeL stellar library for 9 F-type stars COROT


  The Basel Stellar Library (BaSeL models) is constituted of the merging of
various synthetic stellar spectra libraries, with the purpose of giving the
most comprehensive coverage of stellar parameters. It has been corrected for
systematic deviations detected in respect to UBVRIJHKLM photometry at solar
metallicity, and can then be considered as the state-of-the-art knowledge of
the broad band content of stellar spectra. In this paper, we consider a sample
of 9 F-type stars with detailed spectroscopic analysis to investigate the Basel
Stellar Library in two photometric systems simultaneously, Johnson (B-V, U-B)
and Stromgren (b-y, m_1, and c_1). The sample corresponds to potential targets
of the central seismology programme of the COROT space experiment, which have
been recently observed at OHP. The atmospheric parameters T_eff, [Fe/H], and
log g obtained from the BaSeL models are compared with spectroscopic
determinations as well as with results of other photometric calibrations. For a
careful interpretation of the BaSeL solutions, we computed confidence regions
around the best $\chi$^2-estimates and projected them on T_eff-[Fe/H],
T_eff-log g, and log g-[Fe/H] diagrams. (Abridged)

</DOC>
<DOC>
<DOCNO> 122578 </DOCNO>
Radiative hydrodynamics in the highly super adiabatic layer of stellar


  We present results of three dimensional simulations of the uppermost part of
the sun, at 3 stages of its evolution. Each model includes physically realistic
radiative-hydrodynamics (the Eddington approximation is used in the optically
thin region), varying opacities and a realistic equation of state (full
treatment of the ionization of H and He). In each evolution model, we
investigate a domain, which starts at the top of the photosphere and ends just
inside the convection zone (about 2400 km in the sun model). This includes all
of the super-adiabatic layer (SAL). Due to the different positions of the three
models in the $log (g) $ vs $log T_{eff}$ plane, the more evolved models have
lower density atmospheres. The reduction in density causes the amount of
overshoot into the radiation layer, to be greater in the more evolved models.

</DOC>
<DOC>
<DOCNO> 116909 </DOCNO>
Use of Coherent Transition Radiation to Set Up the APS RF Thermionic Gun


  We describe use of the Advanced Photon Source (APS) rf thermionic gun, alpha
magnet beamline, and linac to produce a stable high-brightness beam in excess
of 100 amperes peak current with normalized emittance of 10 pi mm-mrad. To
obtain peak currents greater than 100 amperes, the rf gun system must be tuned
to produce a FWHM bunch length on the order of 350 fs. Bunch lengths this short
are measured using coherent transition radiation (CTR) produced when the rf gun
beam, accelerated to 40 MeV, strikes a metal foil. The CTR is detected using a
Golay detector attached to one arm of a Michelson interferometer. The alpha
magnet current and gun rf phase are adjusted so as to maximize the CTR signal
at the Golay detector, which corresponds to the minimum bunch length. The
interferometer is used to measure the autocorrelation of the CTR radiation. The
minimum phase approximation is used to derive the bunch profile from the
autocorrelation. The high-brightness beam is accelerated to 217 MeV and used to
produce SASE in five APS undulators installed in the Low- Energy Undulator Test
Line (LEUTL) experiment hall. Initial optical measurements showed a gain length
of 1.3 m at 530 nm. * Work supported by U. S. Department of Energy, Office of
Basic Energy Sciences, under Contract No. W-31-109-ENG-38.

</DOC>
<DOC>
<DOCNO> 8119 </DOCNO>
The normal state Fermi surface of pristine and Pb-doped Bi2212 from


  We address the question as to whether the topology of the normal state Fermi
surface of Bi2212 - as seen in angle resolved photoemission - depends on the
photon energy used to measure it. High resolution photoemission spectra and
Fermi surface maps from pristine and Pb-doped Bi2212 are presented, recorded
using both polarised and unpolarised radiation of differing energies. The data
show clearly that no main band crosses the Fermi surface along the GMZ
direction in reciprocal space, even for a photon energy of 32 eV, thus ruling
out the existence of a G-centred, electron-like Fermi surface in this
archetypal high Tc superconductor. The true topology of the normal state Fermi
surface remains that of hole-like barrels centred at the X,Y points of the
Brillouin zone.

</DOC>
<DOC>
<DOCNO> 151679 </DOCNO>
Effective actions on squashed lens spaces


  As a technical exercise with possible relevance to the holographic principle
and string theory, the effective actions (functional determinants) for scalars
and spinors on the squashed three-sphere identified under the action of a
cyclic group, Z_m, are determined. Especially in the extreme oblate squashing
limit, which has a thermodynamic interpretation, the high temperature behaviour
is found as a function of m. Although the intermediate details for odd and even
m are different, the final answers are the same. A thermodynamic interpretation
for spinors is possible only for twisted periodicity conditions and m even.

</DOC>
<DOC>
<DOCNO> 12462 </DOCNO>
Multiple Domain Growth and Memory in the Droplet Model for Spin-Glasses


  We study domain growth dynamics when the target state is suddenly changed on
all length scales. This procedure mimics the `chaos' effect postulated by the
droplet theory of spin-glasses, and allows us to investigate in details its
various dynamical consequences. We study the problem by a variety of methods,
including scaling arguments, analytical solution of the spherical Mattis model,
and Monte Carlo simulations of a 2-dimensional Ising Mattis model. We show that
successive coarsening with respect to different equilibrium states imprints
multiple domain structures on top of each other, plus extra noise due to random
interferences. We demonstrate that the domain structures can be retrieved by an
additional series of coarsening in the reversed order which removes the noises.
We discuss the rejuvenation (chaos) and memory effects observed in
temperature-cycling experiments in glassy systems from the present point of
view, and discuss some open problems and alternative descriptions.

</DOC>
<DOC>
<DOCNO> 117920 </DOCNO>
Lithium abundances in main-sequence F stars and sub-giants


  The application to main-sequence stars of the rotation-induced mixing theory
in the presence of mu-gradients leads to partial mixing in the lithium
destruction region, not visible in the atmosphere. The induced lithium
depletion becomes visible in the sub-giant phase as soon as the convective zone
deepens enough. This may explain why the observed " lithium dilution " is
smoother and the final dilution factor larger than obtained in standard models,
while the lithium abundance variations are very small on the main sequence.

</DOC>
<DOC>
<DOCNO> 170699 </DOCNO>
Optimal encoding and decoding of a spin direction


  For a system of N spins 1/2 there are quantum states that can encode a
direction in an intrinsic way. Information on this direction can later be
decoded by means of a quantum measurement. We present here the optimal encoding
and decoding procedure using the fidelity as a figure of merit. We compute the
maximal fidelity and prove that it is directly related to the largest zeroes of
the Legendre and Jacobi polynomials. We show that this maximal fidelity
approaches unity quadratically in 1/N. We also discuss this result in terms of
the dimension of the encoding Hilbert space.

</DOC>
<DOC>
<DOCNO> 84554 </DOCNO>
Gravitational energy as Noether charge


  A definition of gravitational energy is proposed for any theory described by
a diffeomorphism-invariant Lagrangian. The mathematical structure is a Noether-
current construction of Wald involving the boundary term in the action, but
here it is argued that the physical interpretation of current conservation is
conservation of energy. This leads to a quasi-local energy defined for compact
spatial surfaces. The energy also depends on a vector generating a flow of
time. Angular momentum may be similarly defined, depending on a choice of axial
vector. For Einstein gravity: for the usual vector generating asymptotic time
translations, the energy is the Bondi energy; for a stationary Killing vector,
the energy is the Komar energy; in spherical symmetry, for the Kodama vector,
the energy is the Misner-Sharp energy. In general, the lack of a preferred time
indicates the lack of a preferred energy, reminiscent of the energy-time
duality of quantum theory.

</DOC>
<DOC>
<DOCNO> 8720 </DOCNO>
Coexistence of Singlet and Triplet Attractive Channels in the Pairing


  We propose a phase diagram of quasi-low-dimensional type II superconductors
in parallel magnetic fields, when antiferromagnetic fluctuations contribute to
the pairing interactions. We point out that pairing interactions mediated by
antiferromagnetic fluctuations necessarily include both singlet channels and
triplet channels as attractive interactions. Usually, a singlet pairing is
favored at zero field, but a triplet pairing occurs at high fields where the
singlet pairing is suppressed by the Pauli paramagnetic pair-breaking effect.
As a result, the critical field increases divergently at low temperatures. A
possible relation to experimental phase diagrams of a quasi-one-dimensional
organic superconductor is briefly discussed. We also discuss a possibility that
a triplet superconductivity is observed even at zero field.

</DOC>
<DOC>
<DOCNO> 178919 </DOCNO>
Airy-like patterns in heavy ion elastic scattering


  A semiclassical analysis of an optical potential cross section is presented.
The cross section considered is characterized by the appearance of an Airy-like
pattern. This pattern is similar to that which is present in many cross
sections, which fit the recent measurements of light heavy ion elastic
scattering, and is considered as a manifestation of a rainbow phenomenon. The
semiclassical analysis shows that, in the case considered, the oscillations
arise from the interference between the contributions from two different terms
of a multi-reflection expansion of the scattering function, and, therefore,
cannot be associated with the rainbow phenomenon.

</DOC>
<DOC>
<DOCNO> 122212 </DOCNO>
Energy relaxation in galaxies induced by an external environment and/or


  This paper explores the phenomenon of energy relaxation for stars in a galaxy
embedded in a high density environment that is subjected continually to
perturbations reflecting the presence of other nearby galaxies and/or
incoherent internal pulsations. The analysis is similar to earlier analyses of
energy relaxation induced by binary encounters between nearby stars and between
stars and giant molecular clouds in that the perturbations are idealised as a
sum of near-random events which can be modeled as diffusion and dynamical
friction. However, the analysis differs in one important respect: because the
time scale associated with these perturbations need not be short compared with
the characteristic dynamical time t_D for stars in the original galaxy, the
diffusion process cannot be modeled as resulting from a sequence of
instantaneous kicks, i.e., white noise. Instead, the diffusion is modeled as
resulting from random kicks of finite duration, i.e., coloured noise
characterised by a nonzero autocorrelation time t_c. A detailed analysis of
coloured noise generated by sampling an Ornstein-Uhlenbeck process leads to a
simpling scaling in terms of t_c and an effective diffusion constant D.
Interpreting D and t_c following early work by Chandrasekhar (1941) (the
`nearest neighbour approximation') implies that, for realistic choices of
parameter values, energy relaxation associated with an external environment
and/or internal pulsations could be important on times short compared with the
age of the Universe.

</DOC>
<DOC>
<DOCNO> 178972 </DOCNO>
At the extremes of nuclear charge and spin


  Using scaling rules valid in the liquid drop model of nuclei, as well as
universal rules associated with exchanges of stability in families of
equilibrium configurations, we constructed closed formulae in terms of the
atomic and mass numbers Z and A and the angular momentum L, which represent the
properties of nuclei rotating synchronously (with `rigid' moments of inertia),
as calculated numerically using the Thomas-Fermi model of [5,6]. The formulae
are accurate in the range of mass numbers where the transition to rapidly
elongating triaxial `Jacobi' shapes takes place. An improved set of formulae is
also provided, which takes account of the decreased moments of inertia at low
angular momenta. The formulae should be useful in guiding experimental searches
for the Jacobi transition. In the second part of the paper we discuss
qualitatively some aspects of the dynamics of nucleus-nucleus fusion, and
outline a possible way of estimating cross-sections for the synthesis of
superheavy nuclei.

</DOC>
<DOC>
<DOCNO> 102750 </DOCNO>
A Fredholm Determinant Identity and the Convergence of Moments for


  We obtain an identity between Fredholm determinants of two kinds of
operators, one acting on functions on the unit circle and the other acting on
functions on a subset of the integers. This identity is a generalization of an
identity between a Toeplitz determinant and a Fredholm determinant that has
appeared in the random permutation context. Using this identity, we prove, in
particular, convergence of moments for arbitrary rows of a random Young diagram
under Plancherel measure.

</DOC>
<DOC>
<DOCNO> 40020 </DOCNO>
Direct CP violation in radiative b decays in and beyond the Standard


  We consider the partial rate asymmetry in the inclusive decay modes b to s
gamma and b to d gamma, concentrating on non-standard models with new charged
Higgs interactions. We find that the charged Higgs contribution to the
asymmetry for b to s gamma is small in such models due to a universal
cancellation mechanism. The asymmetry is therefore difficult to distinguish
experimentally from the Standard Model (SM) value, which is also small. The
cancellation mechanism is found to be rendered inoperative in supersymmetry due
to the presence of chargino loops. Unlike b to s gamma, the rate asymmetry for
b to d gamma in Higgs models can be quite different from its SM value,
generally ranging from -20% to +20%. Specific model calculations are performed
for the Three-Higgs Doublet Model and the ``Top'' Two-Higgs Doublet Model to
serve as illustrations. We also offer some suggestions that may be helpful to
experimentalists in the detection of the inclusive mode b to d gamma.

</DOC>
<DOC>
<DOCNO> 117014 </DOCNO>
Circular Orbits Inside the Sphere of Death


  A wheel or sphere rolling without slipping on the inside of a sphere in a
uniform gravitational field can have stable circular orbits that lie wholly
above the "equator", while a particle sliding freely cannot.

</DOC>
<DOC>
<DOCNO> 9549 </DOCNO>
Optical sum rule violation, superfluid weight and condensation energy in


  The model of hole superconductivity predicts that the superfluid weight in
the zero-frequency $\delta$-function in the optical conductivity has an
anomalous contribution from high frequencies, due to lowering of the system's
kinetic energy upon entering the superconducting state. The lowering of kinetic
energy, mainly in-plane in origin, accounts for both the condensation energy of
the superconductor as well as an increased potential energy due to larger
Coulomb repulsion in the paired state. It leads to an apparent violation of the
conductivity sum rule, which in the clean limit we predict to be substantially
larger for in-plane than for c-axis conductivity. However, because cuprates are
in the dirty limit for c-axis transport, the sum rule violation is found to be
greatly enhanced in the c-direction. The model predicts the sum rule violation
to be largest in the underdoped regime and to decrease with doping, more
rapidly in the c-direction that in the plane. So far, experiments have detected
sum rule violation in c-axis transport in several cuprates, as well as a
decrease and disappearance of this violation for increasing doping, but no
violation in-plane. We explore the predictions of the model for a wide range of
parameters, both in the absence and in the presence of disorder, and the
relation with current experimental knowledge.

</DOC>
<DOC>
<DOCNO> 151868 </DOCNO>
Anomaly and Nonplanar Diagrams in Noncommutative Gauge Theories


  Anomalies arising from nonplanar triangle diagrams of noncommutative gauge
theory are studied. Local chiral gauge anomalies for both noncommutative U(1)
and U(N) gauge theories with adjoint matter fields are shown to vanish. For
noncommutative QED with fundamental matters, due to UV/IR mixing a finite
anomaly emerges from the nonplanar contributions. It involves a generalized
$\star$-product of gauge fields.

</DOC>
<DOC>
<DOCNO> 150743 </DOCNO>
On the relevance of tachyons


  We study condensation of open string tachyons using renormalization group
flow in the worldsheet field theory. This approach leads to a simple picture of
the physics of the nontrivial condensate.

</DOC>
<DOC>
<DOCNO> 99835 </DOCNO>
Sur le morphisme de Barth


  Let ${\rm F}$ be a rank-2 semi-stable sheaf on the projective plane, with
Chern classes $c_{1}=0,c_{2}=n$. The curve $\beta_{\rm F}$ of jumping lines of
${\rm F}$, in the dual projective plane, has degree $n$. Let ${\rm M}_{n}$ be
the moduli space of equivalence classes of semi-stables sheaves of rank 2 and
Chern classes $(0,n)$ on the projective plane and ${\cal C}_{n}$ be the
projective space of curves of degree $n$ in the dual projective plane. The
Barth morphism $$\beta: {\rm M}_{n}\longrightarrow{\cal C}_{n}$$ associates the
point $\beta_{\rm F}$ to the class of the sheaf ${\rm F}$. We prove that this
morphism is generically injective for $n\geq 4.$ The image of $\beta$ is a
closed subvariety of dimension $4n-3$ of ${\cal C}_{n}$; as a consequence of
our result, the degree of this image is given by the Donaldson number of index
$4n-3$ of the projective plane.

</DOC>
<DOC>
<DOCNO> 70916 </DOCNO>
Superconformal constraints for QCD conformal anomalies


  Anomalous superconformal Ward identities and commutator algebra in N = 1
super-Yang-Mills theory give rise to constraints between the QCD special
conformal anomalies of conformal composite operators. We evaluate the
superconformal anomalies that appear in the product of renormalized conformal
operators and the trace anomaly in the supersymmetric spinor current and check
the constraints at one-loop order. In this way we prove the universality of QCD
conformal anomalies, which define the non-diagonal part of the anomalous
dimension matrix responsible for scaling violations of exclusive QCD amplitudes
at the next-to-leading order.

</DOC>
<DOC>
<DOCNO> 119433 </DOCNO>
A spectroscopic study of NGC 6251 and its companion galaxies


  Measurements of the velocities of galaxies thought to be associated with the
giant radio galaxy NGC 6251 confirm the presence of a poor cluster with a
systemic redshift of z= 0.0244 +/- 0.0004 and a line-of-sight velocity
dispersion of sigma_{z}= 283 (+109, -52) km/s. This suggests a cluster
atmosphere temperature of T = 0.7 (+0.6, -0.2) keV, which is not enough to
confine the radio jet by gas pressure. The core of NGC 6251 shows strong
emission lines of [O III] and H alpha + [N II], but there is no evidence for
line emission from the jet (detected in optical continuum by Keel (1988)).

</DOC>
<DOC>
<DOCNO> 100273 </DOCNO>
Non-commutative extensions of classical theories in physics


  We present a short introductory overview of the non-commutative extensions of
several classical physical theories. After a general discussion of the reasons
that suggest that the non-commutativity is a major issue that will eventually
lead to the unification of gravity with other fundamental interactions, we
display examples of non-commutative generalizations of known geometries.
Finally we discuss the general properties of the algebras that could become
generalizations of algebras of smooth functions on Minkowskian (Riemannian)
manifolds, needed for the description of Quantum Gravity.

</DOC>
<DOC>
<DOCNO> 118026 </DOCNO>
Delta Scuti stars in stellar systems: on the variability of HD 220392


  HD 220392 (HR 8895), the brightest member of the visual double star CCDM
23239-5349, is a new short-period variable bright star, probably of the Delta
Scuti type. The period analysis performed on the complete set of definitive
Geneva photometry as well as on the data obtained at the ESO 0.5m telescope
shows two periodicities of about 4.7 and 5.5 cycles per day (cpd) with
amplitudes of 0.014 and 0.011 mag respectively. A similar period search on the
(smaller) dataset obtained for the 1 mag fainter B-component, HD 220391,
however shows no periodicity with an amplitude significantly above the noise
level of the data (about 0.006 mag). This difference in variability behaviour
is discussed from the consideration that both stars form a common origin pair
and are located in the Delta Scuti instability strip.

</DOC>
<DOC>
<DOCNO> 85611 </DOCNO>
On the Faddeev-Popov determinant in Regge calculus


  The functional integral measure in the 4D Regge calculus normalised w.r.t.
the DeWitt supermetric on the space of metrics is considered. The Faddeev-Popov
factor in the measure is shown according to the previous author's work on the
continuous fields in Regge calculus to be generally ill-defined due to the
conical singularities. Possible resolution of this problem is discretisation of
the gravity ghost (gauge) field by, e.g., confining ourselves to the affine
transformations of the affine frames in the simplices. This results in the
singularity of the functional measure in the vicinity of the flat background,
where part of the physical degrees of freedom connected with linklengths become
gauge ones.

</DOC>
<DOC>
<DOCNO> 9130 </DOCNO>
A Novel Approach to Spherical Harmonics Expansion for Electron Transport


  A set of equations is derived from the Boltzmann kinetic equation describing
charge transport in semiconductors. The unknowns of these equations depend on
the space-time coordinates and the electron energy. The non-parabolic and
parabolic band approximation are treated in detail. In these cases, the set of
equations is equivalent to those obtained in the spherical-harmonics expansion.
Stationary and homogeneous solutions are explicitly treated. In order to solve
numerically the equations, a cut in the energy range is introduced. The
modified model maintains the physical characteristics of the original
equations. The solution of an asymptotic equation is found and compared to the
numerical solutions.

</DOC>
<DOC>
<DOCNO> 101681 </DOCNO>
Honeycombs and sums of Hermitian matrices


  Horn's conjecture, which given the spectra of two Hermitian matrices
describes the possible spectra of the sum, was recently settled in the
affirmative. In this survey we discuss one of the many steps in this, which
required us to introduce a combinatorial gadget called a {\em honeycomb}; the
question is then reformulable as about the existence of honeycombs with certain
boundary conditions. Another important tool is the connection to the
representation theory of the group U(n), by ``classical vs. quantum''
analogies.

</DOC>
<DOC>
<DOCNO> 101094 </DOCNO>
Twist Positivity for Lagrangian Symmetries


  We prove twist positivity and positivity of the pair correlation function for
combined spatial and internal symmetries of free bosonic Lagrangians. We work
in a general setting, extending the results obtained in Twist Positivity [1].

</DOC>
<DOC>
<DOCNO> 122420 </DOCNO>
An Apparent Gap in Stellar Mass Distributions around 0.7 Solar Masses


  Mass functions for samples of white dwarf stars and for a large heterogeneous
sample of nearby stars appear to have unexplained deficits in the range of 0.70
to 0.75 Solar Masses. The existence, or non-existence, of this anomaly
constitutes a definitive test of a fractal cosmological model that inherently
predicts a gap in stellar mass functions at about 0.73 Solar Masses.

</DOC>
<DOC>
<DOCNO> 150730 </DOCNO>
Quantum spinor field in the FRW universe with a constant electromagnetic


  The article is a natural continuation of our paper {\em Quantum scalar field
in FRW Universe with constant electromagnetic background}, Int. J. Mod. Phys.
{\bf A12}, 4837 (1997). We generalize the latter consideration to the case of
massive spinor field, which is placed in FRW Universe of special type with a
constant electromagnetic field. To this end special sets of exact solutions of
Dirac equation in the background under consideration are constructed and
classified. Using these solutions representations for out-in, in-in, and
out-out spinor Green functions are explicitly constructed as proper-time
integrals over the corresponding contours in complex proper-time plane. The
vacuum-to-vacuum transition amplitude and number of created particles are found
and vacuum instability is discussed. The mean values of the current and
energy-momentum tensor are evaluated, and different approximations for them are
presented. The back reaction related to particle creation and to the
polarization of the unstable vacuum is estimated in different regimes.

</DOC>
<DOC>
<DOCNO> 69407 </DOCNO>
A New Perspective on Cosmic Coincidence Problems


  Cosmological data suggest that we live in an interesting period in the
history of the universe when \rho_\Lambda \sim \rho_M \sim \rho_R. The
occurence of any epoch with such a "triple coincidence" is puzzling, while the
question of why we happen to live during this special epoch is the "Why now?"
problem. We introduce a framework which makes the triple coincidence
inevitable; furthermore, the ``Why now?'' problem is transformed and greatly
ameliorated. The framework assumes that the only relevant mass scales are the
electroweak scale, M_{EW}, and the Planck scale, M_{Pl}, and requires
\rho_\Lambda^{1/4} \sim M_{EW}^2/M_{Pl} parametrically. Assuming that the true
vacuum energy vanishes, we present a simple model where a false vacuum energy
yields a cosmological constant of this form.

</DOC>
<DOC>
<DOCNO> 99660 </DOCNO>
On iterated torus knots and transversal knots


  A knot type is exchange reducible if an arbitrary closed n-braid
representative can be changed to a closed braid of minimum braid index by a
finite sequence of braid isotopies, exchange moves and +/- destabilizations. In
the manuscript [J Birman and NC Wrinkle, On transversally simple knots,
preprint (1999)] a transversal knot in the standard contact structure for S^3
is defined to be transversally simple if it is characterized up to transversal
isotopy by its topological knot type and its self-linking number. Theorem 2 of
Birman and Wrinkle [op cit] establishes that exchange reducibility implies
transversally simplicity. The main result in this note, establishes that
iterated torus knots are exchange reducible. It then follows as a Corollary
that iterated torus knots are transversally simple.

</DOC>
<DOC>
<DOCNO> 39862 </DOCNO>
Large-angle Bhabha scattering and luminosity at flavour factories


  The luminosity determination of electron-positron colliders operating in the
region of low-lying hadronic resonances (E_cm ~ 1-10 GeV), such as BEPC/BES,
DAPHNE, KEKB, PEP-II and VEPP-2M, requires the precision calculation of the
Bhabha process at large scattering angles. In order to achieve a theoretical
accuracy at a few 0.1% level, the inclusion of radiative corrections is
mandatory. The phenomenologically relevant effect of QED corrections is taken
into account in the framework of the Parton Shower (PS) method, which is
employed both for cross section calculation and event generation. To test the
reliability of the approach, a benchmark calculation, including exact O(alpha)
corrections and higher-order leading logarithmic contributions, is developed as
well and compared in detail with the PS predictions. The effect of O(alpha)
next-to-leading and higher-order leading corrections is investigated in the
presence of realistic event selections for the Bhabha process at the
Phi-factories. A new Monte Carlo generator for data analysis (BABAYAGA) is
presented, with an estimated accuracy of 0.5%. Possible developments aiming at
improving its precision and range of applicability are discussed.

</DOC>
<DOC>
<DOCNO> 84868 </DOCNO>
Effect of a neutron-star crust on the r-mode instability


  The presence of a viscous boundary layer under the solid crust of a neutron
star dramatically increases the viscous damping rate of the fluid r-modes. We
improve previous estimates of this damping rate by including the effect of the
Coriolis force on the boundary-layer eigenfunction and by using more realistic
neutron-star models. If the crust is assumed to be perfectly rigid, the
gravitational radiation driven instability in the r-modes is completely
suppressed in neutron stars colder than about 1.5 x 10^8 K. Energy generation
in the boundary layer will heat the star, and will even melt the crust if the
amplitude of the r-mode is large enough. We solve the heat equation explicitly
(including the effects of thermal conduction and neutrino emission) and find
that the r-mode amplitude needed to melt the crust is approximately a_c = 5 x
10^{-3} for maximally rotating neutron stars. If the r-mode saturates at an
amplitude larger than a_c, the heat generated is sufficient to maintain the
outer layers of the star in a mixed fluid-solid state analogous to the pack ice
on the fringes of the Arctic Ocean. We argue that in young, rapidly rotating
neutron stars this effect considerably delays the formation of the crust. By
considering the dissipation in the ice flow, we show that the final spin
frequency of stars with r-mode amplitude of order unity is close to the value
estimated for fluid stars without a crust.

</DOC>
<DOC>
<DOCNO> 14041 </DOCNO>
Characterization of Sleep Stages by Correlations of Heartbeat Increments


  We study correlation properties of the magnitude and the sign of the
increments in the time intervals between successive heartbeats during light
sleep, deep sleep, and REM sleep using the detrended fluctuation analysis
method. We find short-range anticorrelations in the sign time series, which are
strong during deep sleep, weaker during light sleep and even weaker during REM
sleep. In contrast, we find long-range positive correlations in the magnitude
time series, which are strong during REM sleep and weaker during light sleep.
We observe uncorrelated behavior for the magnitude during deep sleep. Since the
magnitude series relates to the nonlinear properties of the original time
series, while the signs series relates to the linear properties, our findings
suggest that the nonlinear properties of the heartbeat dynamics are more
pronounced during REM sleep. Thus, the sign and the magnitude series provide
information which is useful in distinguishing between the sleep stages.

</DOC>
<DOC>
<DOCNO> 101500 </DOCNO>
Effective actions of the unitary group on complex manifolds


  We classify all connected $n$-dimensional complex manifolds admitting an
effective action of the unitary group $U_n$ by biholomorphic transformations.
One consequence of this classification is a characterization of ${\bf C}^n$ by
its automorphism group.

</DOC>
<DOC>
<DOCNO> 152365 </DOCNO>
No Van Dam-Veltman-Zakharov Discontinuity in Ads Space


  We prove that the van Dam-Veltman-Zakharov discontinuity arising in the
massless limit of massive gravity theories is peculiar to Minkowski space and
it is not present in Anti De Sitter space, where the massless limit is smooth.
More generally, the massless limit is smooth whenever the square of the
graviton mass vanishes faster than the cosmological constant.

</DOC>
<DOC>
<DOCNO> 80961 </DOCNO>
Current Status of the Numerical Simulations of d=3 SU(2) Lattice Gauge


  We have continued our systematic investigations of the numerical simulations
of lattice gauge theories in the dual formulation. These include: i) a more
practical implementation of the quasi-local updating technique, ii) a thorough
investigation of the sign problem, iii) issues related to the ergodicity of the
various update algorithms, iv) a novel way of measuring conventional
observables like plaquette in the dual formalism and v) investigations of
thermalisation. While the dual formulation holds out a lot of promises in
principle, there are still some ways to go before it can be made into an
attractive alternative lattice formulation.

</DOC>
<DOC>
<DOCNO> 69631 </DOCNO>
Electroweak Symmetry Breaking by Strong Supersymmetric Dynamics at the


  We construct models in which electroweak symmetry is spontaneously broken by
supersymmetric strong dynamics at the TeV scale. The order parameter is a
composite of scalars, and the longitudinal components of the W and Z are
strongly-coupled bound states of scalars. The usual phenomenological problems
of dynamical electroweak symmetry breaking are absent: the sign of the S
parameter unconstrained in strongly interacting SUSY theories, and fermion
masses are generated without flavor-changing neutral currents or large
corrections to the rho parameter. The lightest neutral Higgs scalar can be
heavier than M_Z without radiative corrections from standard-model fields. All
the mass scales in the model can be naturally related in low-scale models of
supersymmetry breaking. The mu problem can also be solved naturally, and the
model can incorporate perturbative unification of standard-model gauge
couplings with intermediate thresholds.

</DOC>
<DOC>
<DOCNO> 68259 </DOCNO>
Baryogenesis through axion domain wall


  Generic axion models give rise to axion domain walls in the early Universe
and they have to disappear not to overclose the universe, thus limiting the
nature of discrete symmetry allowed in these type of models. Through QCD
sphalerons, net chiral charge can be created by these collapsing walls which in
turn can result the observed baryon assymmetry.

</DOC>
<DOC>
<DOCNO> 12380 </DOCNO>
Dynamical Properties of the 1/r^2-Type Supersymmetric t-J Model in a


  Quasi-particle picture in a magnetic field is pursued for dynamical spin and
charge correlation functions of the one-dimensional supersymmetric t-J model
with inverse-square interaction. With use of exact diagonalization and the
asymptotic Bethe-ansatz equations for finite systems, excitation contents of
relevant excited states are identified which are valid in the thermodynamic
limit. The excitation contents are composed of spinons, antispinons, holons and
antiholons obeying fractional statistics. Both longitudinal and transverse
components of the dynamical spin structure factor are independent of the
electron density in the region where only quasi-particles with spin degrees of
freedom (spinons and antispinons) contribute. The dynamical charge structure
factor does not depend on the spin-polarization density in the region where
only quasi-particles with charge (holons and antiholons) are excited. These
features indicate the strong spin-charge separation in dynamics, reflecting the
high symmetry of the model.

</DOC>
<DOC>
<DOCNO> 121894 </DOCNO>
Image-Subtraction Photometry of Variable Stars in the Field of the


  (Abridged) We present CCD BVI photometry of 85 variable stars from the field
of the globular cluster NGC 6934. The photometry was obtained with the image
subtraction package ISIS. 35 variables are new identifications: 24 RRab stars,
5 RRc stars, 2 eclipsing binaries of W UMa-type, one SX Phe star, and 3
variables of other types. Both detected contact binaries are foreground stars.
The SX Phe variable belongs most likely to the group of cluster blue
stragglers. Large number of newly found RR Lyr variables in this cluster, as
well as in other clusters recently observed by us, indicates that total RR Lyr
population identified up to date in nearby galactic globular clusters is
significantly (>30%) incomplete.
  Fourier decomposition of the light curves of RRc variables was used to
estimate the basic properties of these stars: M=0.63 M_odot,
log(L/L_odot)=1.72, T_eff=7300 and Y=0.27. Using RRab variables we obtain:
M_V=0.81, [Fe/H]=-1.53 and T_eff=6450. From the B-V color at minimum light of
the RRab variables we obtained E(B-V)=0.09+-0.01. Different calibrations of
absolute magnitudes of RRab and RRc available in literature were used to
estimate apparent distance modulus of the cluster: (m-M)_V= 16.09+-0.06. We
note a likely error in the zero point of the HST-based V-band photometry of NGC
6934 recently presented by Piotto et al. Among analyzed sample of RR Lyr stars
we have detected a short period and low amplitude variable which possibly
belongs to the group of second overtone pulsators (RRe subtype variables).
  The BVI photometry of all variables is available electronically via anonymous
ftp. The complete set of the CCD frames is available upon request.

</DOC>
<DOC>
<DOCNO> 101770 </DOCNO>
A note on solvable Lie groups without lattices and the Felix-Thomas


  In this paper we show that a certain solvable Lie group constructed in a
paper by Benson and Gordon has no lattices. This result answers (in the
negative way) a question posed by several authors in the context of symplectic
geometry. The main theorem is proved with the use of rational homotopy theory.

</DOC>
<DOC>
<DOCNO> 102589 </DOCNO>
Maximally symmetric trees


  We characterize the ``best'' model geometries for the class of virtually free
groups, and we show that there is a countable infinity of distinct ``best''
model geometries in an appropriate sense--these are the maximally symmetric
trees. The first theorem gives several equivalent conditions on a bounded
valence, cocompact tree T without valence 1 vertices saying that T is maximally
symmetric. The second theorem gives general constructions for maximally
symmetric trees, showing for instance that every virtually free group has a
maximally symmetric tree for a model geometry.

</DOC>
<DOC>
<DOCNO> 9621 </DOCNO>
Quantum superconductor-metal transition


  We consider a system of superconducting grains embedded in a normal metal. At
zero temperature this system exhibits a quantum superconductor-normal metal
phase transition. This transition can take place at arbitrarily large
conductance of the normal metal.

</DOC>
<DOC>
<DOCNO> 40533 </DOCNO>
A Study of Bs Meson Oscillation Using Ds-Lepton Correlations


  From data collected around the Z resonance by the OPAL detector at LEP, a
sample of Bs decays was obtained using Ds^-l^+ combinations, where the Ds^- was
fully reconstructed in the phi pi-, K*0K- and Ks0K- decay channels or partially
reconstructed in the phi l- nu (X) decay channel. These events were used to
study Bs oscillation. The flavor (b or bbar) at decay was determined from the
lepton charge while the flavor at production was determined from a combination
of techniques. The expected sensitivity of the experiment is 4.1 ps-1. The
experiment was not able to resolve the oscillatory behavior, and we deduced
that the Bs oscillation frequency Delta m_s > 1.0 ps-1 at the 95% confidence
level.

</DOC>
<DOC>
<DOCNO> 120936 </DOCNO>
Protoplanetary disks around Herbig Ae/Be stars: Indications from ISO


  An analysis of solid-state features in infrared spectra of 46 Herbig Ae/Be
stars is presented. The presence of solid-state emission bands is compared to
other indicators of circumstellar material, such as Halpha emission, optical
variability and sub-mm continuum fluxes. The correlation between these
different indicators is weak, if present at all, in our sample. However, a
strong dependence on spectral type of the central star seems to be present:
stars with spectral type earlier than B9 show either amorphous silicate in
absorption or infrared spectra dominated by PAH emission, whereas more than 70%
of the stars of later spectral type show silicate emission. We conclude that
the infrared spectrum of Herbig Be stars is in general dominated by emission
from the circumstellar envelope, whereas the lower-mass Herbig Ae stars show a
spectrum that is dominated by a disk that is passively heated by the central
star.

</DOC>
<DOC>
<DOCNO> 150681 </DOCNO>
Renormalization of the Inverse Square Potential


  The quantum-mechanical D-dimensional inverse square potential is analyzed
using field-theoretic renormalization techniques. A solution is presented for
both the bound-state and scattering sectors of the theory using cutoff and
dimensional regularization. In the renormalized version of the theory, there is
a strong-coupling regime where quantum-mechanical breaking of scale symmetry
takes place through dimensional transmutation, with the creation of a single
bound state and of an energy-dependent s-wave scattering matrix element.

</DOC>
<DOC>
<DOCNO> 84626 </DOCNO>
Absence of Stationary, Spherically Symmetric Black Hole Solutions for


  We study a static, spherically symmetric system of (2j+1) massive Dirac
particles, each having angular momentum j, j=1,2,..., in a classical
gravitational and SU(2) Yang-Mills field. We show that for any black hole
solution of the associated Einstein-Dirac-Yang/Mills equations, the spinors
must vanish identically outside of the event horizon.

</DOC>
<DOC>
<DOCNO> 178535 </DOCNO>
Pion - Nucleon Bremsstrahlung beyond the Soft-Photon approximation


  A dynamical model based on effective Lagrangians is proposed to describe the
bremsstrahlung reaction $ \pi N \to \pi N \gamma$ at low energies. The
$\Delta(1232)$ degrees of freedom are incorporated in a way consistent with
both, electromagnetic gauge invariance and invariance under contact
transformations. The model also includes the initial and final state
rescattering of hadrons via a T-matrix with off the momentum-shell effects. The
double differential distribution of photons is computed for three different
T-matrix models and the results are compared with the soft photon
approximation, and with experimental data. The aim of this analysis is to test
the off-shell behaviour of the different T-matrices under consideration.
Finally an alternative simpler dynamical model that incorporates the unstable
character of the isobar-$\Delta(1232)$ through a complex mass, is presented. As
we will see it is suitable for the study of the magnetic moment of the
resonance.

</DOC>
<DOC>
<DOCNO> 119223 </DOCNO>
Gamma-ray burst afterglows as probes of galactic and intergalactic dust


  The amount and properties of high-redshift galactic and intergalactic (IG)
dust are largely unknown, but could be investigated using multi-wavelength
photometry of high-z objects that have a known intrinsic spectrum. Observations
of gamma-ray burst (GRB) afterglows appear to support the theoretical model of
an adiabatic blast wave expanding into an external medium. In this model, the
synchrotron peak flux is independent of frequency, providing a flat spectrum
when observed over time, and therefore allowing straightforward measurement of
the relative attenuation of afterglow flux in widely separated bands. Applying
this method to dust extinction, we show that for a sample of afterglows which
have been corrected by galactic extinction, comparison between the number
counts of peak fluxes in X-ray versus optical can provide constraints on an
intergalactic component of dust. A similar technique can probe the
redshift-dependence of extinction in GRB-forming regions without requiring an
assumed relation between extinction and reddening by the dust. Probing
systematic changes in extinction with redshift - particularly in IG and/or
non-reddening dust - is crucial to a proper interpretation of the Type Ia
Supernova Hubble diagram and similar observations, and useful in understanding
GRB progenitor environments.

</DOC>
<DOC>
<DOCNO> 83222 </DOCNO>
Fractionally-addressed delay lines


  While traditional implementations of variable-length digital delay lines are
based on a circular buffer accessed by two pointers, we propose an
implementation where a single fractional pointer is used both for read and
write operations. On modern general-purpose architectures, the proposed method
is nearly as efficient as the popularinterpolated circular buffer, and it
behaves well for delay-length modulations commonly found in digital audio
effects. The physical interpretation of the new implementation shows that it is
suitable for simulating tension or density modulations in wave-propagating
media.

</DOC>
<DOC>
<DOCNO> 8764 </DOCNO>
Ferromagnetism and Colossal Magnetoresistance from the Coexistence of


  We report a complete multicomponent mean-field-theory for the coexistence and
competition of charge ordering (CO), antiferromagnetic (AFM) and ferromagnetic
(FM) spin ordering in the presence of a uniform magnetic field. Doping the AFM
or CO state always generates a ferromagnetic component. Itinerant FM, AFM and
CO, necessarily coexist and compete in a particle-hole asymmetric system.
Melting of large AFM-CO orders by small magnetic fields and the related
phenomenon of Colossal Magnetoresistance (CMR) may arise whenever the CO and
AFM order parameters have similar magnitude and momentum structure. Hole doping
favors FM metallic states and CMR while electron doping favors AFM-CO states in
agreement with the phase diagram of perovskite manganites.

</DOC>
<DOC>
<DOCNO> 122543 </DOCNO>
Extensive Serendipitous X-ray Coverage of a Flare Star with ROSAT


  We report the serendipitous discovery of a flare star observed with the ROSAT
X-ray observatory. From optical spectra, which show strong and variable
emission lines of the hydrogen Balmer series and neutral helium, we classify
this object as a M3.0Ve star, and estimate a distance of 52 pc from published
photometry. Due to the star's close proximity (13.6') to the calibration source
and RS CVn binary AR Lacertae, long term X-ray coverage is available in the
ROSAT archive (~50 hours spanning 6.5 years). Two large flare events occurred
early in the mission (6-7/1990), and the end of a third flare was detected in
6/1996. One flare, observed with the Position Sensitive Proportional Counter
(PSPC), had a peak luminosity Lx=1.1x10^{30} erg/s, an e-folding rise time of
2.2 hours and a decay time of 7 hours. This decay time is one of the longest
detected on a dMe star, providing evidence for the possibility of additional
heating during the decay phase. A large HRI flare (peak Lx=2.9x10^{30} erg/s)
is also studied. The "background" X-ray emission is also variable - evidence
for low-level flaring or microflaring. We find that >=59% of the HRI counts and
>=68% of the PSPC counts are due to flares. At least 41% of the HRI exposure
time and 47% of the PSPC are affected by detectable flare enhancement.

</DOC>
<DOC>
<DOCNO> 71050 </DOCNO>
Laboratory Limits on Theories with Sterile Neutrinos in the Bulk


  We discuss the phenomenological consequences of theories which describe
sterile neutrinos in large extra dimensions, in the so-called bulk. We briefly
outline how the cumulative non-decoupling effect due to the tower of
Kaluza-Klein singlet neutrinos may equivalently be described by a
higher-dimensional effective theory with original order-unity Yukawa couplings.
Based on this cumulative phenomenon, we obtain strong constraints on the
fundamental quantum gravity scale and/or on the higher-dimensional Yukawa
couplings.

</DOC>
<DOC>
<DOCNO> 99688 </DOCNO>
A Third-Order Semi-Discrete Central Scheme for Conservation Laws and


  We present a new third-order, semi-discrete, central method for approximating
solutions to multi-dimensional systems of hyperbolic conservation laws,
convection-diffusion equations, and related problems. Our method is a
high-order extension of the recently proposed second-order, semi-discrete
method in [16].
  The method is derived independently of the specific piecewise polynomial
reconstruction which is based on the previously computed cell-averages. We
demonstrate our results, by focusing on the new third-order CWENO
reconstruction presented in [21]. The numerical results we present, show the
desired accuracy, high resolution and robustness of our method.

</DOC>
<DOC>
<DOCNO> 8875 </DOCNO>
Anomalous Proximity Effect in Underdoped YBaCuO Josephson Junctions


  Josephson junctions were photogenerated in underdoped thin films of the
YBa$_2$Cu$_3$O$_{6+x}$ family using a near-field scanning optical microscope.
The observation of the Josephson effect for separations as large as 100 nm
between two wires indicates the existence of an anomalously large proximity
effect and show that the underdoped insulating material in the gap of the
junction is readily perturbed into the superconducting state. The critical
current of the junctions was found to be consistent with the conventional
Josephson relationship. This result constrains the applicability of SO(5)
theory to explain the phase diagram of high critical temperature
superconductors.

</DOC>
<DOC>
<DOCNO> 178392 </DOCNO>
Inertial parameters and superfluid-to-normal phase transition in


  The quasiclassically exact solution for the second inertial parameter $\cal
B$ is found in self-consistent way. It is shown that superdeformation and
nonuniform pairing arising from the rotation induced pair density significantly
reduce this inertial parameter. The different limiting cases for $\cal B$,
which allow to study an interplay between rapid rotation, pairing correlations,
and mean field deformation, are considered. The new signature for the
transition from pairing to normal phase is suggested in terms of the variation
of ${\cal B}/{\cal A}$ versus spin. Experimental data indicate the existence of
such transition in the three superdeformed mass regions.

</DOC>
<DOC>
<DOCNO> 69617 </DOCNO>
Cosmic rays and TeV photons as probes of quantum properties of


  It has been recently observed that small violations of Lorentz invariance, of
a type which may arise in quantum gravity, could explain both the observations
of cosmic rays above the GZK cutoff and the observations of 20-TeV gamma rays
from Markarian 501. We show here that different pictures of the short-distance
structure of space-time would lead to different manifestations of
Lorentz-invariance violation. Specifically, the deformation of Lorentz
invariance needed to resolve these observational paradoxes can only arise
within commutative short-distance pictures of space-time. In noncommutative
space-times there is no anomalous effect, at least at leading order. Also
exploiting the fact that arrival-time delays between high energy photons with
different energies would arise in both the commutative and the noncommutative
Lorentz-violation pictures, we describe an experimental programme, based on
time-of-arrival analysis of high energy photons and searches of violations of
GZK and TeV-photon limits, which could discriminate between alternative
scenarios of Lorentz-invariance breakdown and could provide and unexpected
window on the (quantum) nature of space-time at very short distances.

</DOC>
<DOC>
<DOCNO> 122011 </DOCNO>
The Quiescent Emission Spectrum of Cen X-4 and other X-ray Transients


  We use the observed optical-UV and X-ray emission spectrum of Cen X-4 during
quiescence to constrain models for the accretion flow in this system. We argue
that the optical-UV emission is not due to an optically-thick quiescent
accretion disk, nor due to synchrotron emission from an Advection-Dominated
Accretion Flow (ADAF). Emission from the bright spot could account for the
observed optical-UV component if the mass transfer rate in Cen X-4 is >~
2.10^16 g/s. Although the presence of an ADAF around the neutron star leads to
Compton upscattering of the soft X-ray photons radiated from the stellar
surface, we find that this process alone cannot account for the power law
component seen in the quiescent X-ray spectrum of Cen X-4 and other X-ray
transients containing neutron stars; this result is independent of whether the
source of soft photons is incandescent thermal emission or accretion-powered
emission. We conclude that, in models which invoke the presence of an ADAF and
a propeller effect for the quiescence of X-ray transients containing neutron
stars, the intrinsic emission from the ADAF must contribute very little to the
optical-UV and X-ray emission observed. If these ADAF+propeller models are
correct, the X-ray power law component observed must arise from regions where
the gas impacts the neutron star surface. Variability studies could greatly
help clarify the role of the various emission mechanisms involved.

</DOC>
<DOC>
<DOCNO> 11213 </DOCNO>
Search for incoherent tunnel fluctuations of the magnetisation in


  The magnetic behaviour of nanoparticles of antiferromagnetic ferritin, with a
mean Fe loading of 410 atoms per core, has been investigated by 57Fe Mossbauer
absorption spectroscopy down to very low temperature (34mK). In previous
experi- ments of frequency dependent magnetic susceptibility and magnetic noise
performed at 25mK in similar samples, it was claimed that a resonance at a
frequency of about 10**8 Hz, due to a macroscopic coherent state, had been
observed. However, our search of incoherent tunnel fluctuations around 10**8 Hz
using 57Fe Mossbauer spectroscopy, whose "window" of measurement of fluctuation
frequencies lies in this frequency range, was unsuccessful. This casts a doubt
about the previous observa- tion of macroscopic quantum coherence in ferritin.

</DOC>
<DOC>
<DOCNO> 100280 </DOCNO>
On the multiplicity of terminal singularities on threefolds


  We give the multiplicity of terminal singularities on threefolds by simple
calculation. Then we obtain the best inequalities for the multiplicity and the
index. By using this, we can improve the boundedness number of terminal weak
Q-Fano 3-folds in [KMMT, Theorem 1.2]. Furthermore, we can extended [K, Theorem
3.6] for Fujita freeness conditions to nonhypersurface terminal singularities.

</DOC>
<DOC>
<DOCNO> 13496 </DOCNO>
Small world patterns in food webs


  The analysis of some species-rich, well-defined food webs shows that they
display the so called Small World behavior shared by a number of disparate
complex systems. The three systems analysed (Ythan estuary web, Silwood web and
the Little Rock lake web) have different levels of taxonomic resolution, but
all of them involve high clustering and short path lengths between species.
Additionally, the distribution of connections with fat-tail power law behavior.
These features suggest that communities might be self-organized in such a way
that high homeostasis to perturbations (with short transient times to recovery)
would be at work. The consequences for ecological theory are outlined.

</DOC>
<DOC>
<DOCNO> 84348 </DOCNO>
U. Leonhardt and P. Piwnicki reply to the ``Comment on `Relativistic


  Leonhardt and Piwnicki reply to Visser's ``Comment on `Relativistic Effects
of Light in Moving Media with Extremely Low Group Velocity' ''.

</DOC>
<DOC>
<DOCNO> 100914 </DOCNO>
The Higher Spin Dirac Operators on 3-Dimensional Manifolds


  We study the higher spin Dirac operators on 3-dimensional manifolds and show
that there exist two Laplace type operators for each associated bundle.
Furthermore, we give lower bound estimations for the first eigenvalues of these
Laplace type operators.

</DOC>
<DOC>
<DOCNO> 83299 </DOCNO>
The Sound Manifesto


  Computing practice today depends on visual output to drive almost all user
interaction. Other senses, such as audition, may be totally neglected, or used
tangentially, or used in highly restricted specialized ways. We have excellent
audio rendering through D-A conversion, but we lack rich general facilities for
modeling and manipulating sound comparable in quality and flexibility to
graphics. We need co-ordinated research in several disciplines to improve the
use of sound as an interactive information channel.
  Incremental and separate improvements in synthesis, analysis, speech
processing, audiology, acoustics, music, etc. will not alone produce the
radical progress that we seek in sonic practice. We also need to create a new
central topic of study in digital audio research. The new topic will assimilate
the contributions of different disciplines on a common foundation. The key
central concept that we lack is sound as a general-purpose information channel.
We must investigate the structure of this information channel, which is driven
by the co-operative development of auditory perception and physical sound
production. Particular audible encodings, such as speech and music, illuminate
sonic information by example, but they are no more sufficient for a
characterization than typography is sufficient for a characterization of visual
information.

</DOC>
<DOC>
<DOCNO> 121664 </DOCNO>
Axisymmetry in proto-planetary nebulae: using imaging polarimetry to


  We use ground-based imaging polarimetry to detect and image the dusty
circumstellar envelopes of a sample of proto-planetary nebulae (PPNe) at
near-infrared wavelengths. We detect extended (up to 9 arcsec diameter)
circumstellar envelopes around 15 out of 16 sources with a range of
morphologies including bipolars and shells. The distribution of scattered light
in combination with its polarization (up to 40 per cent) provides unambiguous
evidence for axisymmetry in 14 objects showing this to be a common trait of
PPNe. We suggest that the range of observed envelope morphologies results from
the development of an axisymmetric dust distribution during the superwind phase
at the end of the AGB. We identify shells seen in polarized light with
scattering from these superwind dust distributions which allows us to provide
constraints on the duration of the superwind phase. In one object (IRAS
19475+3119) the circumstellar envelope has a two-armed spiral structure which
we suggest results from the interaction of the mass losing star with a binary
companion.

</DOC>
<DOC>
<DOCNO> 119402 </DOCNO>
Anisotropy of the Hubble Constant in a Cosmological Model with a Local


  A spherical cosmological model with a local void on scales of $\sim 200$ Mpc
and with an inhomogeneous Hubble constant was proposed in recent two papers.
This model explains consistently the observed properties of the cosmic bulk
flow, the accelerating behavior of type Ia supernovae and the CMB dipole
anisotropy without invoking a cosmological constant. As we are in a position
deviated from the center in the model, the anisotropy of the Hubble constant
appears owing to the directional difference of the distance from the observer
to the boundary of the void region. It is found that the anisotropy is
maximally about 6% of the constant in the region of $200 \sim 500$ Mpc from us.
This inhomogeneity and anisotropy of the Hubble constant are not so large as to
be inconsistent with the present observation. The detection of this anisotropy
in the future will be useful to clarify the implication of the inhomogeneity of
the Hubble constant.

</DOC>
<DOC>
<DOCNO> 14137 </DOCNO>
Anomalous isotopic effect near the charge-ordering quantum criticality


  Within the Hubbard-Holstein model, we evaluate the various crossover lines
marking the opening of pseudogaps in the cuprates, which, in our scenario, are
ruled by the proximity to a charge-ordering quantum criticality (stripe
formation). We provide also an analysis of their isotopic dependencies, as
produced by critical fluctuations. We find no isotopic shift of the temperature
$T^0$ marked as a reduction of the quasiparticle density of states in various
experiments, and a substantial positive shift of the pseudogap-formation
temperature $T^*$. We infer that the superconducting critical temperature $T_c$
has almost no shift in the optimally- and overdoped regimes while it has a
small negative isotopic shift in the underdoped, which increses upon
underdoping. We account also for the possible dynamical nature of the
charge-ordering transition, and explain in this way the spread of the values of
$T^*$ and its of isotopic shift, obtained with experimental probes having
different characteristic timescales.

</DOC>
<DOC>
<DOCNO> 70850 </DOCNO>
Nucleons as chiral solitons


  In the limit of large number of colors N the nucleon consisting of N quarks
is heavy, and one can treat it semiclassically, like the large-Z Thomas--Fermi
atom. The role of the semiclassical field binding the quarks in the nucleon is
played by the pion or chiral field; its saddle-point distribution inside the
nucleon is called the chiral soliton. The old Skyrme model for this soliton is
an over-simplification. One can do far better by exploiting a realistic and
theoretically-motivated effective chiral lagrangian presented in this paper. As
a result one gets not only the static characteristics of the nucleon in a fair
accordance with the experiment (such as masses, magnetic moments and
formfactors) but also much more detailed dynamic characteristics like numerous
parton distributions. We review the foundations of the Chiral Quark-Soliton
Model of the nucleon as well as its recent applications to parton
distributions, including the recently introduced `skewed' distributions, and to
the nucleon wave function on the light cone.

</DOC>
<DOC>
<DOCNO> 11359 </DOCNO>
Form Factors for Quasi-particles in c=1 Conformal Field Theory


  The non-Fermi liquid physics at the edge of fractional quantum Hall systems
is described by specific chiral Conformal Field Theories with central charge
c=1. The charged quasi-particles in these theories have fractional charge and
obey a form of fractional statistics. In this paper we study form factors,
which are matrix elements of physical (conformal) operators, evaluated in a
quasi-particle basis that is organized according to the rules of fractional
exclusion statistics. Using the systematics of Jack polynomials, we derive
selection rules for a special class of form factors. We argue that finite
temperature Green's functions can be evaluated via systematic form factor
expansions, using form factors such as those computed in this paper and
thermodynamic distribution functions for fractional exclusion statistics. We
present a specific case study where we demonstrate that the form factor
expansion shows a rapid convergence.

</DOC>
<DOC>
<DOCNO> 117373 </DOCNO>
The Rise Times of High and Low Redshift Type Ia Supernovae are


  We present a self-consistent comparison of the rise times for low- and
high-redshift Type Ia supernovae. Following previous studies, the early light
curve is modeled using a t-squared law, which is then mated with a modified
Leibundgut template light curve. The best-fit t-squared law is determined for
ensemble samples of low- and high-redshift supernovae by fitting simultaneously
for all light curve parameters for all supernovae in each sample. Our method
fully accounts for the non-negligible covariance amongst the light curve
fitting parameters, which previous analyses have neglected. Contrary to Riess
et al. (1999), we find fair to good agreement between the rise times of the
low- and high-redshift Type Ia supernovae. The uncertainty in the rise time of
the high-redshift Type Ia supernovae is presently quite large (roughly +/- 1.2
days statistical), making any search for evidence of evolution based on a
comparison of rise times premature. Furthermore, systematic effects on rise
time determinations from the high-redshift observations, due to the form of the
late-time light curve and the manner in which the light curves of these
supernovae were sampled, can bias the high-redshift rise time determinations by
up to +3.6/-1.9 days under extreme situations. The peak brightnesses - used for
cosmology - do not suffer any significant bias, nor any significant increase in
uncertainty.

</DOC>
<DOC>
<DOCNO> 102770 </DOCNO>
Invitation to higher local fields, Part I, section 5: Kato's higher


  This is a presentation of main ingredients of Kato's higher local class field
theory.

</DOC>
<DOC>
<DOCNO> 119675 </DOCNO>
Testing theories that predict time variation of fundamental constants


  We consider astronomical and local bounds on time variation of fundamental
constants to test some generic Kaluza-Klein-like models and some particular
cases of Beckenstein theory. Bounds on the free parameters of the different
theories are obtained. Furthermore, we find that none of the proposed models,
is able to explain recent results [Webb99,Webb00] claiming an observed
variation of the fine structure constant from quasar absorption systems at
redshifts $0.5<z<3$.

</DOC>
<DOC>
<DOCNO> 102709 </DOCNO>
The Ionization Conjecture in Hartree-Fock Theory


  We prove the ionization conjecture within the Hartree-Fock theory of atoms.
More precisely, we prove that, if the nuclear charge is allowed to tend to
infinity, the maximal negative ionization charge and the ionization energy of
atoms nevertheless remain bounded. Moreover, we show that in Hartree-Fock
theory the radius of an atom (properly defined) is bounded independently of its
nuclear charge.

</DOC>
<DOC>
<DOCNO> 67656 </DOCNO>
High-energy elastic hadron collisions and space structure of hadrons


  The elastic and inelastic profiles have been derived from the measured
elastic differential cross section data with the help of exact impact parameter
representation of elastic scattering amplitude. The results obtained for $pp$
scattering at energy of 53 GeV and $\bar{p} p$ scattering at energy of 541 GeV
have been presented. They indicate that nucleons can be regarded as objects
characterized by a small core (diameter $\sim$ 0.4$\div$0.8 fm) and a half
transparent outer shell (responsible mainly for elastic hadron scattering).

</DOC>
<DOC>
<DOCNO> 14179 </DOCNO>
Zigzag theory of localization in quantum chaos


  This paper has been withdrawn by the author, due a crucial error in Eq. 6.

</DOC>
<DOC>
<DOCNO> 178994 </DOCNO>
Shape Transition in Rare-Earth Nuclei in Relativistic Mean Field Theory


  A systematic study of the temperature dependence of the shapes and pairing
gaps of some isotopes in the rare-earth region is made in the relativistic
Hartree-BCS theory. Thermal response to these nuclei is always found to lead to
a phase transition from the superfluid to the normal phase at a temperature
$T_{\Delta}\sim 0.4 - 0.8$ MeV and a shape transition from prolate to spherical
shapes at $T_c\sim 1.0 - 2.5$ MeV. These shape transition temperatures are
appreciably higher than the corresponding ones calculated in the
non-relativistic framework with the pairing plus quadrupole interaction. Study
of nuclei with continued addition of neutron pairs for a given isotope shows
that with increased ground state deformation, the transition to the spherical
shape is delayed in temperature. A strong linear correlation between
$T_{\Delta}$ and the ground state pairing gap $\Delta^0$ is observed; a well-
marked linear correlation between $T_c$ and the ground state quadrupole
defromation $\beta_2^{0}$ is also seen. The thermal evolution of the
hexadecapole deformation is further presented in the paper.

</DOC>
<DOC>
<DOCNO> 120592 </DOCNO>
A Spectroscopic Analysis of the Energetic Type Ic `Hypernova' SN 1997ef


  The properties of the bright and energetic Type Ic SN 1997ef are investigated
using a Monte Carlo spectrum synthesis code. Analysis of the earliest spectra
is used to determine the time of outburst. The changing features of the
spectrum and the light curve are used to probe the ejecta and to determine
their composition, verifying the results of explosion calculations. Since
synthetic spectra computed using our best explosion model CO100 are only
moderately good reproductions of the observations, the inverse approach is
adopted, and a density structure is derived by demanding that it gives the best
possible fit to the observed spectrum at every epoch analysed. It is found that
the density structure of model CO100 is adequate at intermediate velocities
(5000--25000 km/s), but that a slower density decline ($\rho \propto r^{-4}$)
is required to obtain the extensive line blending at high velocities
(25000--50000 km/s). The `best fit' density distribution results in somewhat
different parameters for the SN, namely an ejecta mass of 9.6$M_\odot$ and an
explosion kinetic energy of 1.75 x 10^{52} erg. The modified density structure
is used to compute a synthetic light curve, which is found to agree very well
with the observed bolometric light curve around maximum. The amount of
radioactive $^{56}$Ni produced by the SN is confirmed at 0.13$M_\odot$. In the
context of an axisymmetric explosion, a somewhat smaller kinetic energy than
that of SN 1998bw may have resulted from the non alignment of the symmetry axis
of the SN and the line of sight. This might also explain the lack of evidence
for a Gamma Ray Burst correlated with SN 1997ef.

</DOC>
<DOC>
<DOCNO> 99449 </DOCNO>
Some cyclic covers of complements of arrangements


  Motivated by the Milnor fiber of a central arrangement, we study the
cohomology of a family of cyclic covers of the complement of an arbitrary
arrangement. We give an explicit proof of the polynomial periodicity of the
Betti numbers of the members of this family of cyclic covers.

</DOC>
<DOC>
<DOCNO> 117697 </DOCNO>
Do wavelets really detect non-Gaussianity in the 4-year COBE data?


  We investigate the detection of non-Gaussianity in the 4-year COBE data
reported by Pando, Valls-Gabaud & Fang (1998), using a technique based on the
discrete wavelet transform. Their analysis was performed on the two DMR faces
centred on the North and South Galactic poles respectively, using the
Daubechies 4 wavelet basis. We show that these results depend critically on the
orientation of the data, and so should be treated with caution. For two
distinct orientations of the data, we calculate unbiased estimates of the
skewness, kurtosis and scale-scale correlation of the corresponding wavelet
coefficients in all of the available scale domains of the transform. We obtain
several detections of non-Gaussianity in the DMR-DSMB map at greater than the
99 per cent confidence level, but most of these occur on pixel-pixel scales and
are therefore not cosmological in origin. Indeed, after removing all multipoles
beyond $\ell = 40$ from the COBE maps, only one robust detection remains.
Moreover, using Monte-Carlo simulations, we find that the probability of
obtaining such a detection by chance is 0.59. We repeat the analysis for the
53+90 GHz coadded COBE map. In this case, after removing $\ell > 40$
multipoles, two non-Gaussian detections at the 99 per cent level remain.
Nevertheless, again using Monte-Carlo simulations, we find that the probability
of obtaining two such detections by chance is 0.28. Thus, we conclude the
wavelet technique does {\em not} yield strong evidence for non-Gaussianity of
cosmological origin in the 4-year COBE data.

</DOC>
<DOC>
<DOCNO> 10110 </DOCNO>
On two continuous models for the dynamics of sandpile surfaces


  We consider a modified BCRE model for pile surface dynamics (Bouchaud, Cates,
Ravi Prakash, and Edwards, J. Phys. I France, v. 4, p. 1383, 1994) and show
that in the long-scale limit this model converges to a quasistationary model of
pile growth in the form of an evolutionary variational inequality (Prigozhin,
Phys. Rev. E, v. 49, p. 1161, 1994).

</DOC>
<DOC>
<DOCNO> 116895 </DOCNO>
The CLIC Main Linac Accelerating Structure


  This paper outlines the RF design of the CLIC (Compact Linear Collider) 30
GHz main linac accelerating structure and gives the resulting longitudinal and
transverse mode properties. The critical requirement for multibunch operation,
that transverse wakefields be suppressed by two orders of magnitude within 0.7
ns (twenty fundamental mode cycles), has been demonstrated in a recent ASSET
experiment. The feasibility of operating the structure at an accelerating
gradient of 150 MV/m for 130 ns has yet to be demonstrated. Damage of the
internal copper surfaces due to high electric fields or resulting from metal
fatigue induced by cyclic surface heating effects are a major concern requiring
further study.

</DOC>
<DOC>
<DOCNO> 121459 </DOCNO>
Acceleration of the Universe


  The cosmological model best capable of fitting current observational data
features two separate epochs during which the Universe is accelerating. During
the earliest stages of the Universe, such acceleration is known as cosmological
inflation, believed to explain the global properties of the Universe and the
origin of structure. Observations of the present state of the Universe strongly
suggest that its density is currently dominated by dark energy with properties
equivalent or similar to a cosmological constant. In these lecture notes, I
provide an introductory account of both topics, including the possibility that
the two epochs may share the same physical description, and give an overview of
the current status.

</DOC>
<DOC>
<DOCNO> 68956 </DOCNO>
On the Sensitivity of the Polarized Parton Densities to Flavour SU(3)


  Motivated by the possibility that it may be misleading to assume SU(3)
symmetry in the analysis of hyperon \beta-decays, we study the sensitivity of
the polarized parton densities, derived from the world data on inclusive
polarized deep inelastic lepton-nucleon scattering, to variation of the value
of the nonsinglet axial charge a_8 from its SU(3) value of 3F-D.

</DOC>
<DOC>
<DOCNO> 99691 </DOCNO>
On Krammer's Representation of the Braid Group


  A connection is made between the Krammer representation and the
Birman-Murakami-Wenzl algebra. Inspired by a dimension argument, a basis is
found for a certain irrep of the algebra, and relations which generate the
matrices are found. Following a rescaling and change of parameters, the
matrices are found to be identical to those of the Krammer representation. The
two representations are thus the same, proving the irreducibility of one and
the faithfulness of the other.

</DOC>
<DOC>
<DOCNO> 13614 </DOCNO>
Variable and reversible quantum structures on a single carbon nanotube


  The band gap of a semiconducting single wall carbon nanotube decreases and
eventually vanishes leading to metalization as a result of increasing radial
deformation. This sets in a band offset between the undeformed and deformed
regions of a single nanotube. Based on the superlattice calculations, we show
that these features can be exploited to realize various quantum well structures
on a single nanotube with variable and reversible electronic properties. These
quantum structures and nanodevices incorporate mechanics and electronics.

</DOC>
<DOC>
<DOCNO> 10551 </DOCNO>
Thermodynamic Properties of a Solid Exhibiting the Energy Spectrum given


  We show that the infinite-dimensional representation of the recently
introduced Logistic algebra can be interpreted as a non-trivial generalization
of the Heisenberg or oscillator algebra. This allow us to construct a quantum
Hamiltonian having the energy spectrum given by the logistic map. We analyze
the Hamiltonian of a solid whose collective modes of vibration are described by
this generalized oscillator and compute the thermodynamic properties of the
model in the two-cycle and r=3.6785 chaotic region of the logistic map.

</DOC>
<DOC>
<DOCNO> 102627 </DOCNO>
Poisson Diffeomorphism Groups


  We construct explicitly a class of coboundary Poisson-Lie structures on the
group of formal diffeomorphisms of ${\Bbb R}^n$. Equivalently, these give rise
to a class of coboundary triangular Lie bialgebra structures on the Lie algebra
$W_n$ of formal vector fields on ${\Bbb R}^n$. We conjecture that this class
accounts for all such coboundary structures. The natural action of the
constructed Poisson-Lie diffeomorphism groups induces large classes of
compatible Poisson structures on ${\Bbb R}^n$, thus making it a Poisson
homogeneous space. Moreover, the left-right action of the Poisson-Lie groups
$FDiff({\Bbb R}^m)\times FDiff({\Bbb R}^n)$ induces classes of compatible
Poisson structures on the space $J^{\infty}({\Bbb R}^m,{\Bbb R}^n)$ of infinite
jets of smooth maps ${\Bbb R}^m\to {\Bbb R}^n$, which makes it also a Poisson
homogeneous space for this action. Initial steps towards classification of
these structures are taken.

</DOC>
<DOC>
<DOCNO> 152519 </DOCNO>
Mass generation with Gauss-Bonnet term : No van Dam-Veltman-Zakharov


  We prove that in anti de Sitter space, there is no van Dam-Veltman-Zakharov
discontinuity in the graviton propagator. Here we obtain the mass term of
$M^2\propto \Lambda^2$ from the Gauss-Bonnet term, which is a ghost-free one.
The condition that the massless limit is smooth is automatically satisfied for
this case.

</DOC>
<DOC>
<DOCNO> 85620 </DOCNO>
Physical Significance of the Difference between the Brans-Dicke Theory


  The asymptotic behavior of the scalar field and its physical meaning are
discussed for T=0 and T\neq 0 for the large enough coupling parameter \omega.
The special character of the Brans-Dicke theory is also discussed for local and
cosmological problems in comparison with general relativity and the selection
rules are introduced respectivley. The scalar field by locally-distributed
matter should exhibit the asymptotic behavior \phi = <\phi> +O(1/\omega)
because of the presence of cosmological matter. The scalar field of a proper
cosmological solution should have the asymptotic form \phi =O(\rho /\omega) and
should converge to zero in the continuous limit \rho /\omega \to 0.

</DOC>
<DOC>
<DOCNO> 119674 </DOCNO>
Dynamics of line-driven disk winds in Active Galactic Nuclei


  We present the results of time-dependent hydrodynamic calculations of line-
driven winds from accretion disks in AGN. To calculate the radiation force, we
take into account radiation from the disk and the central engine. The gas
temperature and ionization state in the wind are calculated self-consistently.
We find that a disk accreting onto a 10^8 MSUN black hole at the rate of 1.8
MSUN/YR can launch a wind at about 10^16 cm from the central engine. The X-rays
from the central object are attenuated by the disk atmosphere so they cannot
prevent the local disk radiation from pushing matter away from the disk. For a
reasonable X-ray opacity, the disk wind can be accelerated by the central UV
radiation to velocities of up to 15000 km/s at a distance of about 10^17 cm
from the central engine. The covering factor of the disk wind is $\sim 0.2$.
The wind is unsteady and consists of an opaque, slow vertical flow near the
disk that is bounded on the polar side by a high-velocity stream. A typical
column density through the fast stream is a few 10^23 cm^-2. The fast stream
contributes nearly 100% to the total wind mass loss rate of 0.5 MSUN/YR.

</DOC>
<DOC>
<DOCNO> 151103 </DOCNO>
Instantons, Monopoles and the Flux Quantization in the Faddeev-Niemi


  We study how instantons arise in the low energy effective theory of the SU(2)
Yang-Mills theory in the context of the non-linear sigma model recently propose
by Faddeev and Niemi. We find a simple relation between the instanton number
$\nu$ and the charge m of the monopole that appears in the effective theory. It
is given by $\nu = m \Phi/(2\pi)$, where $\Phi$ is the quantized flux
associated with a U(1) gauge field passing through the loop formed by the
singularity of the monopole.

</DOC>
<DOC>
<DOCNO> 69261 </DOCNO>
The contribution of the hadronic component of the photon into the


  In the framework of the vector dominance model (VDM) new contribution into
the cross-section of $D^*$-meson photoproduction at HERA has been estimated.
This contribution is due to the interaction of the virtual vector $c\bar
c$-mesons from photon with the proton. It has been shown that the mechanism
under discussion plays the essential role for all values of transverse momentum
of $D^*$-mesons at HERA. Taking into account for the contribution of this
mechanism improves the description of the experimental cross section
distribution.

</DOC>
<DOC>
<DOCNO> 100235 </DOCNO>
Deformation quantization with traces and vanishing of the wheels


  The paper has been withdrawn because the result of math.QA/0002057
"Deformation quantization with traces" holds only for a constant volume form.

</DOC>
<DOC>
<DOCNO> 178720 </DOCNO>
Effective interactions in medium heavy nuclei


  We present a brief overview of microscopic nuclear structure approaches to
nuclei with mass number from 100 to 132. The emphasis is on the shell model and
theories for deriving effective interactions starting from the free
interactions between nucleons. New results for (105,106,107)Sb are presented.

</DOC>
<DOC>
<DOCNO> 117961 </DOCNO>
The spectral variations of the O-type runaway supergiant HD 188209


  We report spectral time series of the late O-type runaway supergiant HD
188209. Radial velocity variations of photospheric absorption lines with a
possible quasi-period ~ 6.4 days have been detected in high-resolution echelle
spectra. Night-to-night variations in the position and strength of the central
emission reversal of the Ha profile occuring over ill-defined time-scales have
been observed. The fundamental parameters of the star have been derived using
state-of-the-art plane--parallel and unified non-LTE model atmospheres, these
last including the mass-loss rate. The derived helium abundance is moderately
enhanced with respect to solar, and the stellar masses are lower than those
predicted by the evolutionary models. The binary nature of this star is not
suggested either from Hipparcos photometry or from radial velocity curves.

</DOC>
<DOC>
<DOCNO> 102391 </DOCNO>
Analogues of Lehmer's conjecture in positive characteristic


  Let $C$ be a smooth irreducible projective curve of genus $g\ge 1$ defined
over a finite field $\mathbb{F}_q$ of $q$ elements. Let $K=\mathbb{F}_q(C)$ be
its function field, $\infty$ a fixed place of $K$ and $A$ the ring of functions
$f\in K$ which are regular everywhere except possibly at $\infty$. Let $\phi$
be a $A$-Drinfeld module defined over a finite extension $L$ of $K$,
$\hat{h}_{\phi}$ its canonical height and $\mathcal{L}=L(2g\infty)$. Then for
every non-torsion element $\alpha\in\overline{K}$ of $\phi$ of degree $d$ of
over $K$ there exists $c=c_{\phi,\mathcal{L},g}>0$ such that
$\hat{h}_{\phi}(\alpha)\ge c(d[L:K])^{-1}$. A similar statement is proved for
the canonical height a point of infinite order of non-constant semi-stable
elliptic curve $E$ defined over $K$.

</DOC>
<DOC>
<DOCNO> 119890 </DOCNO>
Disk-galaxy density distribution from orbital speeds using Newton's law


  Given the dimensions (including thickness) of an axisymmetric galaxy,
Newton's law is used in integral form to find the density distributions
required to match a wide range of orbital speed profiles. Newton's law is not
modified and no dark matter halos are required. The speed distributiions can
have extreme shapes if they are reasonably smooth. Several examples are given.

</DOC>
<DOC>
<DOCNO> 68203 </DOCNO>
Heavy Quark Production at a Linear e^+e^- and Photon Collider and its


  A high energy linear e^+e^- collider (LC) can also be used as a Photon
Collider (PC), using Compton scattering of laser photons on the e^+/e^- beams.
The leading order cross-section for the production of heavy quarks, e^+e^- ->
e^+e^- Q(\bar{Q}) X, at high transverse momenta is calculated for both LC and
PC modes. The sensitivity of this process to the parton distribution
parametrizations of real photons, especially the gluon content, is tested for
both modes.

</DOC>
<DOC>
<DOCNO> 84499 </DOCNO>
Quasars: a supermassive rotating toroidal black hole interpretation


  A supermassive rotating toroidal black hole (TBH) is proposed as the
fundamental structure of quasars and other jet-producing active galactic
nuclei. Rotating protogalaxies gather matter from the central gaseous region
leading to the birth of massive toroidal stars whose internal nuclear reactions
proceed very rapidly. Once the nuclear fuel is spent, gravitational collapse
produces a slender ring-shaped TBH remnant. These events are typically the
first supernovae of the host galaxies. Given time the TBH mass increases
through continued accretion by several orders of magnitude, the event horizon
swells whilst the central aperture shrinks. The difference in angular
velocities between the accreting matter and the TBH induces a magnetic field
that is strongest in the region of the central aperture and innermost
ergoregion. Due to the presence of negative energy states when such a
gravitational vortex is immersed in an electromagnetic field, circumstances are
near ideal for energy extraction via non-thermal radiation including the
Penrose process and superradiant scattering. This establishes a self-sustaining
mechanism whereby the transport of angular momentum away from the quasar by
relativistic bi-directional jets reinforces both the modulating magnetic field
and the TBH/accretion disk angular velocity differential. Quasar behaviour is
extinguished once the BH topology becomes spheroidal. Similar mechanisms may be
operating in microquasars, SNe and GRBs when neutron density or BH tori arise.
In certain circumstances, long-term TBH stability can be maintained by a
negative cosmological constant, otherwise the classical topology theorems must
somehow be circumvented. Preliminary evidence is presented that Planck-scale
quantum effects may be responsible.

</DOC>
<DOC>
<DOCNO> 8255 </DOCNO>
Monte Carlo simulation of a hard-sphere gas in the planar Fourier flow


  By means of the Direct Simulation Monte Carlo method, the Boltzmann equation
is numerically solved for a gas of hard spheres enclosed between two parallel
plates kept at different temperatures and subject to the action of a gravity
field normal to the plates. The profiles of pressure, density, temperature and
heat flux are seen to be quite sensitive to the value of the gravity
acceleration $g$. If the gravity field and the heat flux are parallel ($g>0$),
the magnitudes of both the temperature gradient and the heat flux are smaller
than in the opposite case ($g<0$). When considering the actual heat flux
relative to the value predicted by the Fourier law, it is seen that, if $g>0$,
the ratio increases as the reduced local field strength increases, while the
opposite happens if $g<0$. The simulation results are compared with theoretical
predictions for Maxwell molecules

</DOC>
<DOC>
<DOCNO> 122001 </DOCNO>
A Search for Wolf-Rayet Stars in the Small Magellanic Cloud


  We conducted an extensive search for Wolf-Rayet stars (W-Rs) in the SMC,
using the same interference filter imaging techniques that have proved
successful in finding W-Rs in more distant members of the Local Group.
Photometry of some 1.6 million stellar images resulted in some 20 good
candidates, which we then examined spectroscopically. Two of these indeed
proved to be newly found W-Rs, bringing the total known in the SMC from 9 to
11. Other finds included previously unknown Of-type stars (one as early as
O5f?p)),the recovery of the Luminous Blue Variable S18, and the discovery of a
previously unknown SMC symbiotic star. More important, however, is the fact
that there does not exist a significant number of W-Rs waiting to be discovered
in the SMC. The number of W-Rs in the SMC is a factor of 3 lower than in the
LMC (per unit luminosity), and we argue this is the result of the SMC's low
metallicity on the evolution of the most massive stars.

</DOC>
<DOC>
<DOCNO> 121932 </DOCNO>
A Dust-Penetrated Classification Scheme for Bars as Inferred from their


  The division of galaxies into ``barred'' (SB) and ``normal'' (S) spirals is a
fundamental aspect of the Hubble galaxy classification system. This ``tuning
fork'' view was revised by de Vaucouleurs, whose classification volume
recognized apparent ``bar strength'' (SA, SAB, SB) as a continuous property of
galaxies called the ``family''. However, the SA, SAB, and SB families are
purely visual judgments that can have little bearing on the actual bar strength
in a given galaxy. Until very recently, published bar judgments were based
exclusively on blue light images, where internal extinction or star formation
can either mask a bar completely or give the false impression of a bar in a
nonbarred galaxy. Near-infrared camera arrays, which principally trace the old
stellar populations in both normal and barred galaxies, now facilitate a
quantification of bar strength in terms of their gravitational potentials and
force fields. In this paper, we show that the maximum value, Qb, of the ratio
of the tangential force to the mean radial force is a quantitative measure of
the strength of a bar. Qb does not measure bar ellipticity or bar shape, but
rather depends on the actual forcing due to the bar embedded in its disk. We
show that a wide range of true bar strengths characterizes the category ``SB'',
while de Vaucouleurs category ``SAB'' corresponds to a much narrower range of
bar strengths. We present Qb values for 36 galaxies, and we incorporate our bar
classes into a dust-penetrated classification system for spiral galaxies.

</DOC>
<DOC>
<DOCNO> 10873 </DOCNO>
Phase separation and vortex states in binary mixture of Bose-Einstein


  The phase separation and vortex states in two-component Bose-Einstein
condensate consisting of $|F=1,m_f=-1>$ and $|2,1>$ internal spin states of
$^{87}Rb$ atoms are considered in the framework of Thomas-Fermi approximation.
It is shown that in nonrotating system the atoms in the state $|1,-1>$ form a
shell about the atoms in the state $|2,1>$. The critical angular velocity for
each state is calculated. These velocities are drastically dependent on the
mutual concentrations of the components, the critical angular velocity of the
outer component being less than the angular velocity of the inner one. It is
shown that the atoms in the $|1,-1>$ state can form a rotating ring about the
resting core of the atoms in the state $|2,1>$.

</DOC>
<DOC>
<DOCNO> 118033 </DOCNO>
The dynamical evolution of the dust shell of IRC+10216


  We present high-resolution J-, H-, and K-band observations of the carbon star
IRC+10216. The images were reconstructed from 6 m telescope speckle
interferograms using the bispectrum speckle interferometry method. The H and K
images consist of several compact components within a 0.2" radius and a fainter
asymmetric nebula. The brightest four components are denoted with A to D in the
order of decreasing brightness. A comparison of our images gives - almost like
a movie of five frames - insight to the dynamical evolution of the inner
nebula. For instance, the separation of the two brightest components A and B
increased by almost 40% from 191 mas in 1995 to 265 mas in 1998. At the same
time, component B is fading and the components C and D become brighter. The
X-shaped bipolar structure of the nebula implies an asymmetric mass-loss
suggesting that IRC+10216 is very advanced in its AGB evolution, shortly before
turning into a protoplanetary nebula. The cometary shape of component A
suggests that the core of A is not the central star, but the southern lobe of a
bipolar structure. The position of the central star is probably at or near the
position of component B.

</DOC>
<DOC>
<DOCNO> 122508 </DOCNO>
AD Leo from X-Rays to Radio: Are Flares Responsible for the Heating of


  In spring 1999, a long coordinated observing campaign was performed on the
flare star AD Leo, including {\it EUVE}, {\it BeppoSAX}, the {\it VLA}, and
optical telescopes. The campaign covered a total of 44 days. We obtained
high-quality light curves displaying ongoing variability on various timescales,
raising interesting questions on the role of flare-like events for coronal
heating. We performed Kolmogorov-Smirnov tests to compare the observations with
a large set of simulated light curves composed of statistical flares that are
distributed in energy as a power law of the form ${\rm d}N/{\rm d}E \propto
E^{-\alpha}$ with selectable index $\alpha$. We find best-fit $\alpha$ values
slightly above a value of 2, indicating that the extension of the flare
population toward small energies could be important for the generation of the
overall X-ray emission.

</DOC>
<DOC>
<DOCNO> 80855 </DOCNO>
Disconnected Electromagnetic Form Factors


  Preliminary results of a calculation of disconnected nucleon electromagnetic
factors factors on the lattice are presented. The implementation of the
numerical subtraction scheme is outlined. A comparison of results for electric
and magnetic disconnected form factors on two lattice sizes with those of the
Kentucky group is presented. Unlike previous results, the results found in this
calculation are consistent with zero in these sectors.

</DOC>
<DOC>
<DOCNO> 85446 </DOCNO>
Localization of gravitational energy and its potential to evaluation of


  Vaidya metric as an integral part of the Expansive Nondecelerative Universe
(ENU) model enables to localize the energy of gravitational field and,
subsequently, to find a deep interrelationship between quantum mechanics and
the general theory of relativity. In the present paper, stemming from the ENU
model, ionisation energy and energy of hyperfine splitting of the hydrogen
atom, energy of the elementary quantum of action, as well as the proton and
electron mass are independently expressed through the mass of the planckton, Z
and W bosons and fundamental constants.

</DOC>
<DOC>
<DOCNO> 84609 </DOCNO>
Chaplygin-like gas and branes in black hole bulks


  We explore the possibility to locate a brane in black hole bulks. We study
explicitly the cases of BHTZ and Schwarzschild-anti de Sitter (AdS) black
holes. Our result is that in these cases branes cannot be supported by brane
tension alone and it is necessary to introduce other forms of matter on the
brane. We find classes of perfect fluid solutions obeying to peculiar state
equations. For the case of BHTZ bulk geometry the state equation takes exactly
the form of a ``Chaplygin gas'', which is relevant in the brane context. In the
Schwarzschild-AdS case we find new state equations which reduce to the
Chaplygin form when the brane is located near the horizon.

</DOC>
<DOC>
<DOCNO> 11344 </DOCNO>
Phase transitions and noise crosscorrelations in a model of directed


  We show that effective interactions mediated by disorder between two directed
polymers can be modelled as the crosscorrelation of noises in the
Kardar-Parisi-Zhang (KPZ) equations satisfied by the respective free energies
of these polymers. When there are two polymers, disorder introduces attractive
interactions between them. We analyze the phase diagram in details and show
that these interactions lead to new phases in the phase diagram. We show that,
even in dimension $d=1$, the two directed polymers see the attraction only if
the strength of the disorder potential exceeds a threshold value. We extend our
calculations to show that if there are $m$ polymers in the system then $m$-body
interactions are generated in the disorder averaged effective free energy.

</DOC>
<DOC>
<DOCNO> 70564 </DOCNO>
Polarized J/\psi production in deep inelastic scattering at HERA


  We perform a calculation on the polarization of $J/\psi$ production in deep
inelastic scattering in the HERA energy range. For the inclusive production
distributions, we find that the color-singlet contributions are consistent with
the experimental data in the major region of $z$ ($z>0.4$). Only in low $z$
regions, there are some hints of the need of the color-octet contributions to
describe the experimental data. For the polarization of $J/\psi$ in DIS
processes, we find the parameter $\alpha$ changes with $Q^2$. Especially, at
higher $Q^2$, difference on $\alpha$ between color-singlet and color-octet
contributions become more distinctive. In the two regions of lower and larger
$z$, the polarization parameter $\alpha$ have different features. These
properties can provide important information on polarization mechanism for
$J/\psi$ production.

</DOC>
<DOC>
<DOCNO> 13162 </DOCNO>
Common Origin of Quantum Regression and Quantum Fluctuation Dissipation


  It is shown that the quantum fluctuation dissipation theorem can be
considered as a mathematical formulation in the spectral representation of
Onsager hypothesis on the regression of fluctuations in physical systems. It is
shown that the quantum fluctuation dissipation theorem can be generalized to an
arbitrary stationary state.

</DOC>
<DOC>
<DOCNO> 84320 </DOCNO>
M theory as a matrix extension of Chern-Simons theory


  We study a new class of matrix models, the simplest of which is based on an
Sp(2) symmetry and has a compactification which is equivalent to Chern-Simons
theory on the three-torus. By replacing Sp(2) with the super-algebra Osp(1|32),
which has been conjectured to be the full symmetry group of M theory, we arrive
at a supercovariant matrix model which appears to contain within it the
previously proposed M theory matrix models. There is no background spacetime so
that time and dynamics are introduced via compactifications which break the
full covariance of the model. Three compactifications are studied corresponding
to a hamiltonian quantization in D=10+1, a Lorentz invariant quantization in
D=9+1 and a light cone gauge quantization in D=11=9+1+1. In all cases
constraints arise which eliminate certain higher spin fields in terms of lower
spin dynamical fields. In the SO(9,1) invariant compactification we argue that
the one loop effective action reduces to the IKKT covariant matrix model. In
the light cone gauge compactification the theory contains the standard M theory
light cone gauge matrix model, but there appears an additional transverse five
form field.

</DOC>
<DOC>
<DOCNO> 68262 </DOCNO>
Cosmological and astrophysical bounds on a heavy sterile neutrino and


  Constraints on the lifetime of the heavy sterile neutrino, that was proposed
as a possible interpretation of the KARMEN anomaly, are derived from primordial
nucleosynthesis and SN 1987A. Together with the recent experimental bounds on
the nu_s lifetime, SN 1987A completely excludes this interpretation.
Nucleosynthesis arguments permit a narrow window for the lifetime in the
interval 0.1-0.2 sec. If nu_s possesses an anomalous interaction with nucleons,
the SN bounds may not apply, while the nucleosynthesis ones would remain valid.

</DOC>
<DOC>
<DOCNO> 150706 </DOCNO>
Gravity and antigravity in a brane world with metastable gravitons :


  In the framework of a five-dimensional three-brane model with quasi-localized
gravitons we evaluate metric perturbations induced on the positive tension
brane by matter residing thereon. We find that at intermediate distances, the
effective four-dimensional theory coincides, up to small corrections, with
General Relativity. This is in accord with Csaki, Erlich and Hollowood and in
contrast to Dvali, Gabadadze and Porrati. We show, however, that at ultra-large
distances this effective four-dimensional theory becomes dramatically
different: conventional tensor gravity changes into scalar anti-gravity.

</DOC>
<DOC>
<DOCNO> 71778 </DOCNO>
New unitarity triangles of quark mixing and CP violation


  Unitarity of the Cabibbo-Kobayashi-Maskawa matrix gives rise to nine new
unitarity triangles in the standard model.

</DOC>
<DOC>
<DOCNO> 150714 </DOCNO>
Kaehler forms and cosmological solutions in type II supergravities


  We consider cosmological solutions to type II supergravity theories where the
spacetime is split into a FRW universe and a K\"ahler space, which may be taken
to be Calabi-Yau. The various 2-forms present in the theories are taken to be
proportional to the K\"ahler form associated to the K\"ahler space.

</DOC>
<DOC>
<DOCNO> 101274 </DOCNO>
Alternating sign matrices and tournaments


  We settle a question of Bressoud concerning the existence of an explicit
bijection from a class of oriented square-ice graphs to a class of tournaments.
We give an algorithm constructing such a bijection.

</DOC>
<DOC>
<DOCNO> 8425 </DOCNO>
Partition Function Zeros and Finite Size Scaling of Helix-Coil


  We report on multicanonical simulations of the helix-coil transition of a
polypeptide. The nature of this transition was studied by calculating partition
function zeros and the finite-size scaling of various quantities. Estimates for
critical exponents are presented.

</DOC>
<DOC>
<DOCNO> 117927 </DOCNO>
Collisional dark matter and the structure of dark halos


  We study how the internal structure of dark halos is affected if Cold Dark
Matter particles are assumed to have a large cross-section for elastic
collisions. We identify a cluster halo in a large cosmological N-body
simulation and resimulate its formation with progressively increasing
resolution. We compare the structure found in the two cases where dark matter
is treated as collisionless or as a fluid. For the collisionless case our
results agree with those of other workers. Collisional dark matter results in a
cluster which is more nearly spherical and has a more singular central density
profile. Substructure within the cluster is only weakly suppressed relative to
the collisionless case. The observed structure of dwarf galaxies argues against
self-interacting dark matter if, as seems likely, intermediate cross-sections
produce structure lying between the extremes we have simulated.

</DOC>
<DOC>
<DOCNO> 7665 </DOCNO>
Composite Pairings in Chirally Stabilized Critical Fluids


  We study a one-dimensional electron gas in a special antiferromagnetic
environment made by two spin-1/2 Heisenberg chains and the one-dimensional
two-channel Kondo-Heisenberg lattice away from half-filling. These models flow
to an intermediate fixed point which belongs to the universality class of
chirally stabilized liquids. Using a Toulouse point approach, the universal
properties of the models are determined as well as the identification of the
leading instabilities. It is shown that these models exhibit a non-Fermi liquid
behavior with strong enhanced composite pairing correlations.

</DOC>
<DOC>
<DOCNO> 68466 </DOCNO>
Two problems in thermal field theory


  In this talk, I review recent progress made in two areas of thermal field
theory. In particular, I discuss various approaches for the calculation of the
quark gluon plasma thermodynamical properties, and the problem of its photon
production rate.

</DOC>
<DOC>
<DOCNO> 170418 </DOCNO>
Concepts of a quantum information theory of many letters


  A theoretical framework is presented allowing the treatment of quantum
messages with components of variable length. To this aim a many-letter space,
similiar to the Fock space, is constructed, generalizing the standard quantum
information theory of block messages of fixed length. In the many-letter space
a length operator can be defined measuring the length of a quantum message,
whose eigenspaces are the block Hilbert spaces used in the standard theory.

</DOC>
<DOC>
<DOCNO> 101616 </DOCNO>
The Hurwitz Enumeration Problem of Branched Covers and Hodge Integrals


  We use algebraic methods to compute the simple Hurwitz numbers for arbitrary
source and target Riemann surfaces. For an elliptic curve target, we reproduce
the results previously obtained by string theorists. Motivated by the
Gromov-Witten potentials, we find a general generating function for the simple
Hurwitz numbers in terms of the representation theory of the symmetric group
S_n. We also find a generating function for Hodge integrals on the moduli space
M_{g,2} of Riemann surfaces with two marked points, similar to that found by
Faber and Pandharipande for the case of one marked point.

</DOC>
<DOC>
<DOCNO> 12246 </DOCNO>
Charge Fluctuations in the Single Electron Box


  Quantum fluctuations of the charge in the single electron box are
investigated. Based on a diagrammatic expansion we calculate the average island
charge number and the effective charging energy in third order in the tunneling
conductance. Near the degeneracy point where the energy of two charge states
coincides, the perturbative approach fails, and we explicitly resum the leading
logarithmic divergencies to all orders. The predictions for zero temperature
are compared with Monte Carlo data and with recent renormalization group
results. While good agreement between the third order result and numerical data
justifies the perturbative approach in most of the parameter regime relevant
experimentally, near the degeneracy point and at zero temperature the
resummation is shown to be insufficient to describe strong tunneling effects
quantitatively. We also determine the charge noise spectrum employing a
projection operator technique. Former perturbative and semiclassical results
are extended by the approach.

</DOC>
<DOC>
<DOCNO> 11199 </DOCNO>
Non-equilibrium electronic transport and interaction in short metallic


  We have observed interaction effects in the differential conductance $G$ of
short, disordered metal bridges in a well-controlled non-equilibrium situation,
where the distribution function has a double Fermi step. A logarithmic scaling
law is found both for the temperature and for the voltage dependence of $G$ in
all samples. The absence of magnetic field dependence and the low
dimensionality of our samples allow us to distinguish between several possible
interaction effects, proposed recently in nanoscopic samples. The universal
scaling curve is explained quantitatively by the theory of electron-electron
interaction in diffusive metals, adapted to the present case, where the sample
size is smaller than the thermal diffusion length.

</DOC>
<DOC>
<DOCNO> 13473 </DOCNO>
Electron-Like Fermi Surface and Remnant (pi,0) Feature in Overdoped


  We have performed an angle-resolved photoemission study of overdoped
La1.78Sr0.22CuO4, and have observed sharp nodal quasiparticle peaks in the
second Brillouin zone that are comparable to data from Bi2Sr2CaCu2O8+d. The
data analysis using energy distribution curves, momentum distribution curves
and intensity maps all show evidence of an electron-like Fermi surface, which
is well explained by band structure calculations. Evidence for many-body
effects are also found in the substantial spectral weight remaining below the
Fermi level around (pi,0), where the band is predicted to lie above EF.

</DOC>
<DOC>
<DOCNO> 151642 </DOCNO>
p-Brane Action from Gravi-Dilaton Effective Action


  Using a special ansatz for the metric, by straightforward computation we
prove that gravi-dilaton effective action in higher dimensions is reduced to
the p-brane action. The dual symmetry of the generic type
$%a\longleftrightarrow \frac 1a$ is an important symmetry of the reduced
action.

</DOC>
<DOC>
<DOCNO> 120257 </DOCNO>
Distribution of Cold dust in Orion A and B


  Large scale far-infrared (FIR) observations of the Orion complex at 205 and
138 micron are presented with an aim of studying the distribution of cold (< 25
K) dust. The maps in these FIR bands extend over approximately 3600 sq. arcmin
and cover regions around OMC-1, 2, 3 in Orion A and NGC 2023 and NGC 2024 in
Orion B. Some limited regions have also been mapped at 57 micron. A total of 15
sources in Orion A and 14 in Orion B (south) have been identified from our FIR
maps. Dust temperature distribution in both Orion A and Orion B (south) have
been determined reliably using the maps at 205 & 138 micron obtained from
simultaneous observations using almost identical beams (1.6 dia). These
temperatures have been used to generate map of the optical depth at 150 micron,
for the Orion B region. The coldest source detected is in OMC-3 and has a
temperature of about 15 K. The diffuse FIR emission in the different
sub-regions is found to vary between 25% to 50% of the total FIR emission from
that sub-region.

</DOC>
<DOC>
<DOCNO> 116806 </DOCNO>
Acceleration for the mu-Storage Ring Neutrino Source


  A muon storage ring neutrino source uses an induction linac for muon capture,
a 200 MHz copper cavity system for cooling, and 200 and 400 MHz superconducting
rf systems for acceleration to a final energy of up to 50 GeV. These systems
and their requirements are discussed in this paper.

</DOC>
<DOC>
<DOCNO> 119362 </DOCNO>
Getting the Red Out: A Stellar Approach to Determining Spatial


  By employing two different spectroscopic techniques we have mapped out the
variable ISM dust extinction endemic to globular cluster M4. We derive an
average E(B-V) reddening of 0.33 +/- 0.01 and R = 3.4 +/- 0.4, both in good
agreement with previous studies of M4. For individual stars in the most heavily
reddened regions of M4, we find E(B-V) values significantly higher than those
inferred by studies of interstellar gas; for heavily reddened regions, the gas
measured in column density measurements may not completely trace the dust.

</DOC>
<DOC>
<DOCNO> 84436 </DOCNO>
Uniform Spaces in the Pregeometric Modeling of Quantum Non-Separability


  We introduce a pregeometry employing uniform spaces over the denumerable set
X of spacetime events. The discrete uniformity D_X over X is used to obtain a
pregeometric model of macroscopic spacetime neighborhoods. We then use a
uniformity base generated by a topological group structure over X to provide a
pregeometric model of microscopic spacetime neighborhoods. Accordingly, quantum
non-separability as it pertains to non-locality is understood pregeometrically
as a contrast between microscopic spacetime neighborhoods and macroscopic
spacetime neighborhoods. A nexus between this pregeometry and conventional
spacetime physics is implied per the metric induced by D_X. A metric over the
topological group Z2 x ... x Z2 is so generated. Implications for quantum
gravity are enumerated.

</DOC>
<DOC>
<DOCNO> 100357 </DOCNO>
A Note on Regularized Shannon's Sampling Formulae


  Error estimation is given for a regularized Shannon's sampling formulae,
which was found to be accurate and robust for numerically solving partial
differential equations.

</DOC>
<DOC>
<DOCNO> 68609 </DOCNO>
Construction of a Minimal Higgs SO(10) SUSY GUT Model


  A full account is given of the procedure used by the authors to construct an
SO(10) supersymmetric grand unified model of the fermion mass matrices. Various
features of the model which gives remarkably accurate results for the quark and
lepton masses and mixings were presented earlier in separate publications. The
construction of the matrices is first discussed in the framework of effective
operators, from which one naturally obtains the maximal \nu_\mu - \nu_\tau
mixing, while the small angle or maximal mixing solutions for the solar
neutrinos depend upon the nature of the Majorana matrix. A set of Higgs and
fermion superfields is then introduced from which the Higgs and Yukawa
superpotentials uniquely give the structure of the mass matrices previously
obtained. The right-handed Majorana matrix arises from one Higgs field coupling
to several pairs of superheavy conjugate neutrino singlets. For the simple
version considered, 10 input parameters accurately yield the 20 masses and
mixings of the quarks and leptons, and the 3 masses of the right-handed
neutrinos.

</DOC>
<DOC>
<DOCNO> 69288 </DOCNO>
Neutrino Propagation In Color Superconducting Quark Matter


  We calculate the neutrino mean free path in color superconducting quark
matter, and employ it to study the cooling of matter via neutrino diffusion in
the superconducting phase as compared to a free quark phase. The cooling
process slows when quark matter undergoes a second order phase transition to a
superconducting phase at the critical temperature $T_c$. Cooling subsequently
accelerates as the temperature decreases below $T_c$. This will directly impact
the early evolution of a newly born neutron star should its core contain quark
matter. Consequently, there may be observable changes in the early neutrino
emission which would provide evidence for superconductivity in hot and dense
matter.

</DOC>
<DOC>
<DOCNO> 119635 </DOCNO>
High redshift radio galaxies


  There is considerable evidence that powerful radio quasars and radio galaxies
are orientation-dependent manifestations of the same parent population: massive
spheroids containing correspondingly massive black holes. Following the
recognition of this unification, research is directed to the task of
elucidating the structure and composition of the active nuclei and their hosts
to understand the formation and evolution of what we expect to become the most
massive of galaxies. In contrast to the quasars, where the nucleus can outshine
the galaxy at optical/near infrared wavelengths by a large factor, the radio
galaxies contain a 'built-in coronograph' that obscures our direct view to the
nucleus. These objects present our best opportunity to study the host galaxy in
detail. Of particular interest are those sources with redshifts greater than
about 2 that represent an epoch when nuclear activity was much more common that
it is now and when we believe these objects were in the process of assembly. In
combination with high resolution imaging from space (HST), optical
spectropolarimetry with Keck II allows us to clearly separate the scattered
nuclear radiation from the stellar and gaseous emission from the host galaxy.
The rest-frame ultraviolet emission line spectra suggest that rapid chemical
evolution is occurring at this epoch. Near infrared spectroscopy with the VLT
is giving us access to both the lines and continuum in the rest-frame optical
spectrum, allowing investigations of the evolved stellar population and
extending the composition analysis with measurements of the familiar
forbidden-line spectrum.

</DOC>
<DOC>
<DOCNO> 85384 </DOCNO>
Closed Universe in Mirage Cosmology


  We study the cosmological evolution of the closed universe on a spherical
probe brane moving in the AdS$_m\times S^n$ background and the near-horizon
background of the dilatonic D-branes. The Friedmann equations describing the
evolution of the brane universe, and the effective energy density and pressure
simulated on the probe brane due to its motion in the curved background
spacetime are obtained and analyzed. We also comment on the relevance of the
spherical probe brane to the giant graviton for the special value of the probe
energy.

</DOC>
<DOC>
<DOCNO> 152591 </DOCNO>
Quantum BRST operators in the extended BRST-anti-BRST formalism


  The quantum BRST-anti-BRST operators are explicitely derived and the
consequences related to correlation functions are investigated. The connection
with the standard formalism and the loopwise expansions for quantum operators
and anomalies in Sp(2) approach are analyzed.

</DOC>
<DOC>
<DOCNO> 170779 </DOCNO>
Avoiding Quantum Chaos in Quantum Computation


  We study a one-dimensional chain of nuclear $1/2-$spins in an external
time-dependent magnetic field. This model is considered as a possible candidate
for experimental realization of quantum computation. According to the general
theory of interacting particles, one of the most dangerous effects is quantum
chaos which can destroy the stability of quantum operations. According to the
standard viewpoint, the threshold for the onset of quantum chaos due to an
interaction between spins (qubits) strongly decreases with an increase of the
number of qubits. Contrary to this opinion, we show that the presence of a
magnetic field gradient helps to avoid quantum chaos which turns out to
disappear with an increase of the number of qubits. We give analytical
estimates which explain this effect, together with numerical data supporting

</DOC>
<DOC>
<DOCNO> 85433 </DOCNO>
Non-vanishing Magnetic Flux through the Slightly-charged Kerr Black Hole


  In association with the Blanford-Znajek mechanism for rotational energy
extraction from Kerr black holes, it is of some interest to explore how much of
magnetic flux can actually penetrate the horizon at least in idealized
situations. For completely uncharged Kerr hole case, it has been known for some
time that the magnetic flux gets entirely expelled when the hole is
maximally-rotating. In the mean time, it is known that when the rotating hole
is immersed in an originally uniform magnetic field surrounded by an ionized
interstellar medium (plasma), which is a more realistic situation, the hole
accretes certain amount of electric charge. In the present work, it is
demonstrated that as a result of this accretion charge small enough not to
disturb the geometry, the magnetic flux through this slightly charged Kerr hole
depends not only on the hole's angular momentum but on the hole's charge as
well such that it never vanishes for any value of the hole's angular momentum.

</DOC>
<DOC>
<DOCNO> 102116 </DOCNO>
Finiteness for Arithmetic Fewnomial Systems


  Suppose L is any finite algebraic extension of either the ordinary rational
numbers or the p-adic rational numbers. Also let g_1,...,g_k be polynomials in
n variables, with coefficients in L, such that the total number of monomial
terms appearing in at least one g_i is exactly m. We prove that the maximum
number of isolated roots of G:=(g_1,...,g_k) in L^n is finite and depends
solely on (m,n,L), i.e., is independent of the degrees of the g_i. We thus
obtain an arithmetic analogue of Khovanski's Theorem on Fewnomials, extending
earlier work of Denef, Van den Dries, Lipshitz, and Lenstra.

</DOC>
<DOC>
<DOCNO> 12465 </DOCNO>
A magnetic barrier in confined two-dimensional electron gases:


  We investigate the conductance properties of a hybrid
ferromagnet-semiconductor structure consisting of a confined two-dimensional
electron gas and a transverse ferromagnetic strip on top. Within the framework
of the Landauer-B\"uttiker model, we develop an alternative way to consider
magnetic fields. Our method describes devices ranging from a recently realized
nanomagnetometer down to quasi one-dimensional quantum wires. We provide a
rigorous way to relate the measured resistance to the actual magnetization of
the strip. Regarding the quasi one-dimensional wires we propose a new device
application, a tunable magnetic switch.

</DOC>
<DOC>
<DOCNO> 39945 </DOCNO>
Measurements of the bb~ production cross section and forward backward


  The measurements of Rb = sigma(e+e- -> bb~)/sigma(e+e- -> qq~) and of the b
quark forward-backward charge asymmetry, A^b_fb, at centre-of-mass energies
above the Z pole are described. The measurement of Rb is performed at \root{s}
between 130 and 189 GeV using a b-tagging method that exploits the relatively
large decay length of b-hadrons. The measurement of A^b_fb is performed using
the large statistics event sample collected at \root{s}=189 GeV with a
lepton-tag analysis based on the selection of prompt muons and electrons. The
results at \root{s}=189 GeV are: Rb = 0.163 +/- 0.013 (stat.) +/- 0.005
(syst.), A^b_fb = 0.61 +/- 0.18 (stat.) +/- 0.09 (syst.).

</DOC>
<DOC>
<DOCNO> 7927 </DOCNO>
Superconductivity in a Ferromagnetic Layered Compound


  We examine superconductivity in layered systems with large Fermi-surface
splitting due to coexisting ferromagnetic layers. In particular, the hybrid
ruthenate-cuprate compound RuSr_2GdCu_2O_8 is examined on the coexistence of
the superconductivity and the ferromagnetism, which has been observed recently.
We calculate critical fields of the superconductivity taking into account the
Fulde-Ferrell-Larkin-Ovchinnikov state in a model with Fermi-surfaces which
shapes are similar to those obtained by a band calculation. It is shown that
the critical field is enhanced remarkably due to a Fermi-surface effect, and
can be high enough to make the coexistence possible in a microscopic scale. We
also clarify the direction of the spatial oscillation of the order parameter,
which may be observed by scanning tunneling microscope experiments.

</DOC>
<DOC>
<DOCNO> 100756 </DOCNO>
Graph Theoretic Construction of Discrete Groups over p-adic Fields


  This paper is originally designed as a part of revision of the author's
preprint math.AG/9908174 "P-adic Schwarzian triangle groups of Mumford type".
Recently, Yves Andr'e pointed out a flaw in that preprint; more precisely,
Proposition II there was not correct, and consequently, as he pointed out, some
triangle groups are missing (but only in p=2,3,5). I apologize to the readers,
and will release the other part soon by the original title. In this paper, we
concentrate on the constructive part, but more systematically and in more
general situation. More precisely, this paper presents a complete criterion for
an abstract tree of groups to be realized in the context of p-adic
uniformization. This criterion provides a practical way of constructing
finitely generated discrete subgroups in PGL(2,K) over a p-adic field K. In the
end of this paper, we will exhibit concrete examples of such construction,
which in particular shows that there exist infinitely many triangle groups.

</DOC>
<DOC>
<DOCNO> 99560 </DOCNO>
A Mixture of the Exclusion Process and the Voter Model


  We consider a one-dimensional nearest-neighbor interacting particle system,
which is a mixture of the simple exclusion process and the voter model. The
state space is taken to be the countable set of the configurations that have a
finite number of particles to the right of the origin and a finite number of
empty sites to the left of it. We obtain criteria for the ergodicity and some
other properties of this system using the method of Lyapunov functions.

</DOC>
<DOC>
<DOCNO> 100201 </DOCNO>
The Askey-Wilson function transform


  In this paper we present an explicit (rank one) function transform which
contains several Jacobi-type function transforms and Hankel-type transforms as
degenerate cases. The kernel of the transform, which is given explicitly in
terms of basic hypergeometric series, thus generalizes the Jacobi function as
well as the Bessel function. The kernel is named the Askey-Wilson function,
since it provides an analytical continuation of the Askey-Wilson polynomial in
its degree. In this paper we establish the $L^2$-theory of the Askey-Wilson
function transform, and we explicitely determine its inversion formula.

</DOC>
<DOC>
<DOCNO> 12856 </DOCNO>
Effect of inelastic scattering on the average Coulomb-blockade peak


  The average height of the Coulomb-blockade conductance peaks for chaotic
elastic scattering is known to increase by a factor of 4/3 upon breaking
time-reversal symmetry. We calculate the temperature dependence of this factor
in the regime that the inelastic scattering rate Gamma_in is greater than the
mean tunneling rate Gamma_el, which itself is less than the mean level spacing
Delta. Comparison with recent experimental data by Folk et al.
(cond-mat/0008052) demonstrates that Gamma_in lies below Gamma_el and hence
also below Delta, consistent with the low-energy suppression of inelastic
electron-electron scattering in quantum dots.

</DOC>
<DOC>
<DOCNO> 150941 </DOCNO>
The dynamics of zeros of the elliptic solutions to the Schrodinger


  J. F. van Diejen and H. Puschmann have recently shown that the dynamics of
zeros of the n-solitonic solutions to the Schrodinger equation with the
reflectionless potential is governed by a rational Ruijsenaars-Schneider
system. We use the algebraic-geometrical construction of solutions to the
Schrodinger equation to generalize this result to the elliptic case.

</DOC>
<DOC>
<DOCNO> 11191 </DOCNO>
Local properties and Density of States in the two-dimensional p-d Model


  The p-d model which well describes the CuO_2 planes of the high-Tc
superconductors is studied by means of the Composite Operator Method (COM). The
relevant quasi-particle excitations are represented by composite operators. As
a result of taking into account spin excitations we find a p- like band near
the Fermi level. The dispersion of this band gives a Fermi surface which is in
good agreement with the experimental measurements. Due to the strong mixing of
the relevant excitations, the spectral weight of this band is reduced and gives
a large Fermi surface in the moderately doped region. The dependence of the
calculated physical quantities on model parameters, temperature and doping, is
in a very good agreement with the available Quantum Monte Carlo results.

</DOC>
<DOC>
<DOCNO> 7944 </DOCNO>
Uptake of gases in bundles of carbon nanotubes


  Model calculations are presented which predict whether or not an arbitrary
gas experiences significant absorption within carbon nanotubes and/or bundles
of nanotubes. The potentials used in these calculations assume a conventional
form, based on a sum of two-body interactions with individual carbon atoms; the
latter employ energy and distance parameters which are derived from empirical
combining rules. The results confirm intuitive expectation that small atoms and
molecules are absorbed within both the interstitial channels and the tubes,
while large atoms and molecules are absorbed almost exclusively within the
tubes.

</DOC>
<DOC>
<DOCNO> 169736 </DOCNO>
Parallel Quantum Computation, the Library of Babel and Quantum


  The complementary roles played by parallel quantum computation and quantum
measurement in originating the quantum speed-up are illustrated through an
analogy with a famous metaphor by J.L. Borges.

</DOC>
<DOC>
<DOCNO> 14027 </DOCNO>
Photon Green's function and the Casimir energy in a medium


  A new expansion is established for the Green's function of the
electromagnetic field in a medium with arbitrary $\epsilon$ and $\mu$. The
obtained Born series are shown to consist of two types of interactions - the
usual terms (denoted $\cal P$) that appear in the Lifshitz theory combined with
a new kind of terms (which we denote by $\cal Q$) associated with the changes
in the permeability of the medium. Within this framework the case of uniform
velocity of light ($\epsilon\mu={\rm const}$) is studied. We obtain expressions
for the Casimir energy density and the first non-vanishing contribution is
manipulated to a simplified form. For (arbitrary) spherically symmetric $\mu$
we obtain a simple expression for the electromagnetic energy density, and as an
example we obtain from it the Casimir energy of a dielectric-diamagnetic ball.
It seems that the technique presented can be applied to a variety of problems
directly, without expanding the eigenmodes of the problem and using boundary
condition considerations.

</DOC>
<DOC>
<DOCNO> 69276 </DOCNO>
Gravitino Dark Matter without R-parity


  Cosmological issues are examined when gravitino is the lightest superparticle
(LSP) and R-parity is broken. Decays of the next lightest superparticles occur
rapidly via R-parity violating interaction, and thus they do not upset the
big-bang nucleosynthesis, unlike the R-parity conserving case. The gravitino
LSP becomes unstable, but its lifetime is typically much longer than the age of
the Universe. It turns out that observations of diffuse photon background
coming from radiative decays of the gravitino do not severely constrain the
gravitino abundance, and thus the gravitino weighing less than around 1 GeV can
be dark matter of the Universe when bilinear R-parity violation generates a
neutrino mass which accounts for the atmospheric neutrino anomaly.

</DOC>
<DOC>
<DOCNO> 39997 </DOCNO>
First results from phi -> KL KS decays with the KLOE detector


  The KLOE experiment has collected 2.4 1/pb of integrated luminosity during
the commissioning of the DAFNE phi-factory in 1999. The performance of the
detector has been studied using phi -> KL KS decays collected during this
period, yielding also first measurements of relevant K parameters such as
masses and lifetimes. A clean Kshort -> pi+ pi- sample is used to select Klong
-> 2pi CP-violating decays and Klong -> Kshort regeneration events in the
detector material. Results on the regeneration probability in
beryllium-alluminum alloy and carbon-fiber plus aluminum composite are
presented.

</DOC>
<DOC>
<DOCNO> 170189 </DOCNO>
Decoherence-Free Subspaces for Multiple-Qubit Errors: (II) Universal,


  Decoherence-free subspaces (DFSs) shield quantum information from errors
induced by the interaction with an uncontrollable environment. Here we study a
model of correlated errors forming an Abelian subgroup (stabilizer) of the
Pauli group (the group of tensor products of Pauli matrices). Unlike previous
studies of DFSs, this type of errors does not involve any spatial symmetry
assumptions on the system-environment interaction. We solve the problem of
universal, fault-tolerant quantum computation on the associated class of DFSs.

</DOC>
<DOC>
<DOCNO> 121537 </DOCNO>
Submillimetre sources in rich cluster fields - source counts, redshift


  Recent submillimetre surveys have revealed a population of dusty, high
redshift sources of great cosmological significance for understanding
dust-enshrouded star formation in distant galaxies, and for determining the
origin of the far-IR background. In this paper, we analyze nine rich cluster
fields mapped at 850 and 450 microns with the SCUBA array on the James Clerk
Maxwell telescope. Lensing models of the clusters are developed in order to
derive accurate source counts for our sample. VLA maps of the same clusters are
used to help constrain the redshift distribution of our SCUBA detections.
Implications for high redshift galaxies and for the far-IR background are
discussed. We also provide limits on distributed dust produced by cooling flows
in these clusters.

</DOC>
<DOC>
<DOCNO> 68370 </DOCNO>
Chiral symmetry breaking, color superconductivity and quark matter phase


  We discuss in this note simultaneous existence of chiral symmetry breaking
and color superconductivity at finite temperature and density in a
Nambu-Jona-Lasinio type model. The methodology involves an explicit
construction of a variational ground state and minimisation of the
thermodynamic potential. There exists solutions to the gap equations at finite
densities with both quark antiquark as well as diquark condensates for the
"ground" state. However, such a phase is thermodynamically unstable with the
pressure being negative in this region. We also compute the equation of state,
and obtain the structure of the phase diagram in the model.

</DOC>
<DOC>
<DOCNO> 12814 </DOCNO>
Magnetic catalysis in QED_3 at finite temperature: beyond the constant


  We solve the Schwinger-Dyson equations for (2+1)-dimensional QED in the
presence of a strong external magnetic field. The calculation is done at finite
temperature and the fermionic self energy is not supposed to be
momentum-independent, which is the usual simplification in such calculations.
The phase diagram in the temperature-magnetic field plane is determined. For
intermediate magnetic fields the critical temperature turns out to have a
square root dependence on the magnetic field, but for very strong magnetic
fields it approaches a B-independent limiting value.

</DOC>
<DOC>
<DOCNO> 9143 </DOCNO>
Ultrafast spin dynamics and critical behavior in half-metallic


  Ultrafast spin dynamics in ferromagnetic half-metallic compound Sr_2FeMoO_6
is investigated by pump-probe measurements of magneto-optical Kerr effect.
Half-metallic nature of this material gives rise to anomalous thermal
insulation between spins and electrons, and allows us to pursue the spin
dynamics from a few to several hundred picoseconds after the optical
excitation. The optically detected magnetization dynamics clearly shows the
crossover from microscopic photoinduced demagnetization to macroscopic critical
behavior with universal power law divergence of relaxation time for wide
dynamical critical region.

</DOC>
<DOC>
<DOCNO> 121232 </DOCNO>
On the presence of Silicon and Carbon in the pre-maximum spectrum of the


  The spectrum of the normal Type Ia SN 1990N observed very early on (14 days
before B maximum) was analysed by Fisher et al (1997), who showed that the
large width and the unusual profile of the strong line near 6000\AA can be
reproduced if the line is assumed to be due to \CII 6578, 6583\AA and if Carbon
is located in a high velocity shell. This line is one of the characterising
features of SNe Ia, and is usually thought to be due to \SiII. A Monte Carlo
spectrum synthesis code was used to investigate this suggestion further. The
result is that if a standard explosion model is used the mass enclosed in the
shell at the required high velocity (25,000--35,000 \kms) is too small to give
rise to a strong \CII line. At the same time, removing Silicon has a negative
effect on the synthetic spectrum at other wavelengths, and removing Carbon from
the lower velocity regions near the photosphere makes it difficult to reproduce
two weak lines which are naturally explained as \CII, one of them being the
line which Fisher et al (1997) suggested is responsible for the strong 6000\AA
feature. However, synthetic spectra confirm that although \SiII can reproduce
most of the observed 6000\AA line, the red wing of the line extends too far to
be compatible with a \SiII origin, and that the flat bottom of the line is also
not easy to reproduce. The best fit is obtained for a normal SN Ia abundance
mix at velocities near the photosphere (15,500-19,000 \kms) and an outer
Carbon-Silicon shell beyond 20,000 \kms. This suggests that mixing is not
complete in the outer ejecta of a SN Ia. Observations at even earlier epochs
might reveal to what extent a Carbon shell is unmixed.

</DOC>
<DOC>
<DOCNO> 8157 </DOCNO>
From mesoscopic magnetism to the anomalous 0.7 conductance plateau


  We present a simple phenomenological model which offers a unifying
interpretation of the experimental observations on the 0.7 conductance anomaly
of quantum point contacts. The model utilizes the Landauer-Buttiker formalism
and involves enhanced spin correlations and thermal depopulation of spin
subbands. In particular our model can account for the plateau value 0.7 and the
unusual temperature and magnetic field dependence. Furthermore it predicts an
anomalous suppression of shot noise at the 0.7 plateau.

</DOC>
<DOC>
<DOCNO> 121220 </DOCNO>
Magnetohydrodynamical Non-radiative Accretion Flows in Two-Dimensions


  We present the results of axisymmetric, time-dependent magnetohydrodynamic
simulations of accretion flows around black holes. The calculations begin from
a rotationally supported thick torus which contains a weak poloidal field.
Accretion is produced by growth and saturation of the magnetorotational
instability (MRI) provided the wavelength of the fastest growing mode is less
than the thickness of the torus. Using a computational grid that spans more
than two decades in radius, we compare the time-averaged properties of the flow
to previous hydrodynamical simulations. The net mass accretion rate is small
compared to the mass inflow and outflow rates at large radii associated with
turbulent eddies. Turbulence is driven by the MRI rather than convection. The
two-dimensional structure of the time-averaged flow is significantly different
compared to the hydrodynamical case. We discuss the limitations imposed on our
results by the assumption of axisymmetry and the relatively small radial
domain.

</DOC>
<DOC>
<DOCNO> 122162 </DOCNO>
Local Distance Indicators


  A summary is given of the calibration of the Cepheid scale required in the
derivation of distances from observations at V and I, as in the HST work on
extragalactic Cepheids. There is some evidence that a small metallicity
correction may be necessary in deriving distances in this way. The evidence for
this comes both from observations of Cepheids of different metallicities and
from a comparison of the LMC distance modulus derived from Cepheids and that
derived by other methods.

</DOC>
<DOC>
<DOCNO> 83053 </DOCNO>
Von Neumann Quantum Logic vs. Classical von Neumann Architecture?


  The name of John von Neumann is common both in quantum mechanics and computer
science. Are they really two absolutely unconnected areas? Many works devoted
to quantum computations and communications are serious argument to suggest
about existence of such a relation, but it is impossible to touch the new and
active theme in a short review. In the paper are described the structures and
models of linear algebra and just due to their generality it is possible to use
universal description of very different areas as quantum mechanics and theory
of Bayesian image analysis, associative memory, neural networks, fuzzy logic.

</DOC>
<DOC>
<DOCNO> 117768 </DOCNO>
The Mid-Infrared Spectra of Normal Galaxies


  The mid-infrared spectra (2.5 to 5 and 5.7 to 11.6 mu) obtained by ISO-PHOT
reveal the interstellar medium emission from galaxies powered by star formation
to be strongly dominated by the aromatic features at 6.2, 7.7, 8.6 and 11.3 mu.
Additional emission appears in-between the features, and an underlying
continuum is clearly evident at 3-5 mu. This continuum would contribute about a
third of the luminosity in the 3 to 13 mu range. The features together carry 5
to 30% of the 40-to-120 mu `FIR' luminosity. The relative fluxes in individual
features depend very weakly on galaxy parameters such as the far-infrared
colors, direct evidence that the emitting particles are not in thermal
equilibrium. The dip at 10 mu is unlikely to result from silicate absorption,
since its shape is invariant among galaxies. The continuum component has a f_nu
\~ nu^{0.65} shape between 3 and 5 mu and carries 1 to 4% of the FIR luminosity;
its extrapolation to longer wavelengths falls well below the spectrum in the 6
to 12 mu range. This continuum component is almost certainly of non-stellar
origin, and is probably due to fluctuating grains without aromatic features.
The spectra reported here typify the integrated emission from the interstellar
medium of the majority of star-forming galaxies, and could thus be used to
obtain redshifts of highly extincted galaxies up to z=3 with SIRTF.

</DOC>
<DOC>
<DOCNO> 101722 </DOCNO>
On the Distribution Function of the Complexity of Finite Sequences


  Investigations of complexity of sequences lead to important applications such
as effective data compression, testing of randomness, discriminating between
information sources and many others. In this paper we establish formulas
describing the distribution functions of random variables representing the
complexity of finite sequences introduced by Lempel and Ziv in 1976. We show
that the distribution functions depend in an affine way on the probabilities of
the so called "exact" sequences.

</DOC>
<DOC>
<DOCNO> 70781 </DOCNO>
Conceptual aspects of QCD factorization in hadronic B decays


  I review the meaning of ``QCD factorization'' in hadronic two-body B decays
and then discuss recent results of theoretical (rather than phenomenological)
nature: the proof of factorization at two loops; the identification of
``chirally enhanced'' power corrections; and the role of annihilation
contributions.

</DOC>
<DOC>
<DOCNO> 85323 </DOCNO>
One-loop graviton corrections to Maxwell's equations


  We compute the graviton induced corrections to Maxwell's equations in the
one-loop and weak field approximations. The corrected equations are analogous
to the classical equations in anisotropic and inhomogeneous media. We analyze
in particular the corrections to the dispersion relations. When the wavelength
of the electromagnetic field is much smaller than a typical length scale of the
graviton two-point function, the speed of light depends on the direction of
propagation and on the polarisation of the radiation. In the opposite case, the
speed of light may also depend on the energy of the electromagnetic radiation.
We study in detail wave propagation in two special backgrounds, flat
Robertson-Walker and static, spherically symmetric spacetimes. In the case of a
flat Robertson-Walker gravitational background we find that the corrected
electromagnetic field equations correspond to an isotropic medium with a
time-dependent effective refractive index. For a static, spherically symmetric
background the graviton fluctuations induce a vacuum structure which causes
birefringence in the propagation of light.

</DOC>
<DOC>
<DOCNO> 101558 </DOCNO>
A Pieri-type Formula for the Equivariant Cohomology of the Flag Manifold


  We prove an explicit combinatorial formula for certain structure constants of
the T-equivariant cohomology of the flag manifold SLn/B. Our result generalizes
the Pieri-type formula in ordinary cohomology proved by Sottile in 1996. Our
result also gives a Pieri-type formula for the double Schubert polynomials
introduced by Lascoux and Schutzenberger.

</DOC>
<DOC>
<DOCNO> 13983 </DOCNO>
Quantum Algorithms for Fermionic Simulations


  We investigate the simulation of fermionic systems on a quantum computer. We
show in detail how quantum computers avoid the dynamical sign problem present
in classical simulations of these systems, therefore reducing a problem
believed to be of exponential complexity into one of polynomial complexity. The
key to our demonstration is the spin-particle connection (or generalized
Jordan-Wigner transformation) that allows exact algebraic invertible mappings
of operators with different statistical properties. We give an explicit
implementation of a simple problem using a quantum computer based on standard
qubits.

</DOC>
<DOC>
<DOCNO> 69286 </DOCNO>
Report of the Working Group on Photon and Weak Boson Production


  This report discusses physics issues which can be addressed in photon and
weak boson production in Run II at the Tevatron. The current understanding and
the potential of Run II to expand our knowledge of direct photon production in
hadronic collisions is discussed. We explore the prospects for using the
W-boson cross section to measure the integrated luminosity, improving the
measurement of the W and Z boson transverse momentum distributions, the Z ->
b\bar b signal, and the lepton angular distribution in W decays. Finally, we
consider the prospects for measuring the trilinear gauge boson couplings in Run
II.

</DOC>
<DOC>
<DOCNO> 71070 </DOCNO>
Strangeness Equilibration at GSI Energies


  We develop the notion of "broad-band equilibration" in heavy-ion processes
involving dense medium. Given density-dependent \Km-masses we show that the
equilibration at GSI energies claimed to hold in previous treatments down to
$\sim \rho_0/4$, can be replaced by a broad-band equilibration in which the
\Km-meson and hyperons are produced in an essentially constant ratio
independent of density. There are experimental indications that this also holds
for AGS energies. We then proceed to argue that {\it both} $K^+$ and $K^-$ must
get lighter in dense medium at some density $\rho >\rho_0$ due to the
decoupling of the vector mesons. As a consequence, kaon condensation in compact
stars could take place {\it before} chiral restoration since the sum of bare
quark masses in the kaon should lie below $\mu_e$. Another consequence of the
decoupling vector interactions is that the quasi-particle picture involving
(quasi)quarks, presumably ineffective at low densities, becomes more
appropriate at higher densities as chiral restoration is approached.

</DOC>
<DOC>
<DOCNO> 84643 </DOCNO>
Extremely charged static perfect fluid distributions with dilaton in


  We examine charged static perfect fluid distributions with a dilaton field in
the frame-work of general relativity. We consider the case that the Einstein
equations reduce to a non-linear version of Poisson equation. We show that
Maxwell equation and an equation for a dilaton imply the relation among the
charge, mass and dilatonic charge densities.

</DOC>
<DOC>
<DOCNO> 67845 </DOCNO>
On the Quark-Quark Superconducting Pairing Induced by Instantons in QCD


  The superconducting pairing of quarks induced by instantons in QCD is studied
by means of the functional integral method. The integral equation determining
the critical temperature of the superconducting phase transition is
established. It is shown that the Bose condensate of diquarks consists of color
antitriplet $(\bar{3}) $ scalar diquarks

</DOC>
<DOC>
<DOCNO> 40136 </DOCNO>
How to Interpret a Tau Excess at LEP2 within the MSSM


  Neutralino and tau slepton pair production can naturally produce an excess of
tau lepton pairs at the current LEP collider energies. We describe the
constraints this has on the values of the mass parameters in the softly broken
Supersymmetric Lagrangian, and consider the consequences for superpartner
production at LEP and at the Fermilab Tevatron collider. The pair production of
the LSP and a heavier neutralino, followed by a 2-body decay to a tau slepton
and tau lepton, is consistent with the present LEP data, predicts a chargino
mass below 125 GeV, and provides an interesting Cold Dark Matter component,
with a relic matter density of .1-.2.

</DOC>
<DOC>
<DOCNO> 12216 </DOCNO>
The Bethe lattice spin glass revisited


  So far the problem of a spin glass on a Bethe lattice has been solved only at
the replica symmetric level, which is wrong in the spin glass phase. Because of
some technical difficulties, attempts at deriving a replica symmetry breaking
solution have been confined to some perturbative regimes, high connectivity
lattices or temperature close to the critical temperature.
  Using the cavity method, we propose a general non perturbative solution of
the Bethe lattice spin glass problem at a level of approximation which is
equivalent to a one step replica symmetry breaking solution. The results
compare well with numerical simulations. The method can be used for many finite
connectivity problems appearing in combinatorial optimization.

</DOC>
<DOC>
<DOCNO> 120851 </DOCNO>
Influence of Cooled Interstellar Gas on the Fundamental Plane for


  We explore the possibly important influence of cooled interstellar gas on the
fundamental plane of elliptical galaxies. Interstellar cooling is described by
a parameterized sink term in the equation of continuity. Parameters that give
the best fits to the X-ray observations of NGC 4472 are used as a template for
the radial distribution of interstellar cooling in structurally homologous
elliptical galaxies of lower mass. Gas that cools within an effective radius
can contribute an additional 10 - 30 percent to the mass of the old stellar
population. If the cooled gas forms into stars of very low mass, $\ll
M_{\odot}$, as is commonly assumed, the cooled mass is optically dark. As a
result, the mass to light ratios determined from stellar velocities
systematically overestimate that of the old stellar population. Moreover, the
total mass and spatial distribution of the optically dark young stellar
population does not scale homologously with galactic luminosity or radius and
the total stellar mass to light ratio varies with galactic radius. We
investigate the non-homologous perturbations of cooled gas on the mass to light
ratio for several idealized homologous elliptical galaxies and show that they
appear to be incompatible with the observed thinness of the fundamental plane.
If optically luminous young stars formed from the cooled gas, the disturbance
of the fundamental plane would be lessened.

</DOC>
<DOC>
<DOCNO> 102138 </DOCNO>
Higher direct images of Lagrangian fibrations


  We prove that the higher direct images of the dualizing sheaf of a Lagrangian
fibration between smooth projective manifolds are isomorphic to the cotangent
bundles of base space.
 As a corollary, we obtain that every Hodge number of the base space of a fibre
space of an irreducible symplectic manifold is the same to that of a projective
space if the base space is smooth.

</DOC>
<DOC>
<DOCNO> 84677 </DOCNO>
The maximal slicing of a Schwarzschild black hole


  We describe recent work due to Niall \'O Murchadha and the author (Phys. Rev.
D57, 4728 (1998)) on the late time behaviour of the maximal foliation of the
extended Schwarzschild geometry which results from evolving a time symmetric
slice into the past and future, with time running equally fast at both spatial
ends of the manifold. We study the lapse function of this foliation in the
limit where proper time-at-infinity goes to ${+\infty}$ or ${-\infty}$ and the
slices approach $r=3m/2$.

</DOC>
<DOC>
<DOCNO> 170357 </DOCNO>
Dynamical Revivals in Fermi Accelerator Model


  We investigate quantum revivals in the dynamics of an atom in an atomic Fermi
accelerator. It is demonstrated that the external driving field influences the
revival time significantly. Analytical expressions are presented which are
based on semiclassical secular theory. These analytical results explain the
dependence of the revival time on the characteristic parameters of the problem
quantitatively in a simple way. They are in excellent agreement with numerical
results.

</DOC>
<DOC>
<DOCNO> 120401 </DOCNO>
The optical polarization of spiral galaxies


  Scattering of starlight by dust, molecules and electrons in spiral galaxies
will produce a modification of the direct intensity and a polarization in the
observed light. We treat the case where the distribution of scatterers can be
considered to be optically thin, and derive semi-analytic expressions for the
resolved intensity and polarized intensity for Thomson, Rayleigh, and more
general scattering mechanisms. These expressions are applied to a parametric
model spiral galaxies. It is further shown that in the case of Thomson and
Rayleigh scattering, and when scatterers and stars are distributed with
rotational symmetry, the total polarized flux depends on the inclination, $i$,
of the galactic axis to the line of sight according to a simple $\sin ^2 i$
law. This generalises the well known result for pointlike and spherical light
sources. By using a method based on spherical harmonics, we generalise this law
for more general mechanisms, and show that to good approximation, the $\sin ^2
i$ law still holds for the class of models considered.

</DOC>
<DOC>
<DOCNO> 68058 </DOCNO>
Experimental signature of a fermiophobic Higgs boson


  The most general Two Higgs Doublet Model potential without explicit CP
violation depends on 10 real independent parameters . Excluding spontaneous CP
violation results in two 7 parameter models. Although both models give rise to
5 scalar particles and 2 mixing angles, the resulting phenomenology of the
scalar sectors is different. If flavour changing neutral currents at tree level
are to be avoided, one has four alternative ways of introducing the fermion
couplings in both cases. In one of these models the mixing angle of the CP even
sector can be chosen in such a way that the fermion couplings to the lightest
scalar Higgs boson vanishes. At the same time it is possible to suppress the
fermion couplings to the charged and pseudo-scalar Higgs boson by appropriately
choosing the mixing angle of the CP odd sector. We investigate the
phenomenology of both models in the fermiophobic limit and present the
different branching ratios for the decays of the scalar particles. We use the
present experimental results from the LEP collider to constrain the models.

</DOC>
<DOC>
<DOCNO> 150912 </DOCNO>
New Brane Solutions from Killing Spinor Equations


  In a recent paper, we have pointed out a relation between the Killing spinor
and Einstein equations. Using this relation, new brane solutions of D=11 and
D=10 type IIB supergravity theories are constructed. It is shown that in a
brane solution, the flat world-volume directions, the smeared transverse
directions and the sphere located at a fixed radial distance can be replaced
with any Lorentzian Ricci flat, Euclidean Ricci flat and Einstein manifolds,
respectively. The solution obtained in this fashion is supersymmetric when the
Ricci flat and Einstein manifolds have Killing spinors. We generalize
intersecting brane solutions, in which M5, M2 and D3-branes also wrap over the
cycles determined by the K\"{a}hler forms of Ricci flat K\"{a}hler manifolds.
New, singular, Ricci flat manifolds as (generalized) cones over the U(1)
bundles over Ricci flat K\"{a}hler spaces are constructed. These manifolds have
covariantly constant spinors and give rise to new, supersymmetric, Ricci flat
compactifications of non-gauged supergravity theories. We find M2 and D3-brane
solutions, which asymptotically approach these singular vacua.

</DOC>
<DOC>
<DOCNO> 122147 </DOCNO>
The z=0.0912 and z=0.2212 Damped Lyman Alpha Galaxies Along the


  New optical and infrared observations along the sight-line toward the quasar
OI 363 (0738+313) are presented and discussed. Excluding systems which lack
confirming UV spectroscopic observations of the actual Lyman alpha line, this
sight-line presently contains the two lowest-redshift classical damped Lyman
alpha (DLA) quasar absorption line systems known (i.e. with N(HI) \ge 2 x
10^{20} atoms cm^{-2}), one at z(abs)=0.0912 and the other at z(abs)=0.2212.
The z=0.09 DLA galaxy appears to be an extended low surface brightness galaxy
which is easily visible only in infrared images and shows rich morphological
structure. Subtraction of the quasar nuclear and host light yields L_K \approx
0.08L_K* at z=0.09. The impact parameter between the galaxy and quasar
sight-line is very small, b<3.6 kpc (<2 arcsec), which makes measurements
difficult. The z=0.22 DLA galaxy is an early-type dwarf with a K-band
luminosity of L_K \approx 0.1L_K* at impact parameter b=20 kpc. In general,
these results serve to support mounting evidence that DLA galaxies are drawn
from a wide variety of gas-rich galaxy types. (Abridged)

</DOC>
<DOC>
<DOCNO> 102491 </DOCNO>
Bounding by canonical functions, with CH


  We show that that a certain class of semi-proper iterations does not add
omega-sequences. As a result, starting from suitable large cardinals one can
obtain a model in which the Continuum Hypothesis holds and every function from
omega_1 to omega_1 is bounded by a canonical function on a club, and so omega_1
is the omega_2-nd canonical function.

</DOC>
<DOC>
<DOCNO> 84205 </DOCNO>
Dynamics of a string coupled to gravitational waves - Gravitational wave


  We study the perturbative dynamics of an infinite gravitating Nambu-Goto
string within the general-relativistic perturbation framework. We develop the
gauge invariant metric perturbation on a spacetime containing a
self-gravitating straight string with a finite thickness and solve the
linearized Einstein equation. In the thin string case, we show that the string
does not emit gravitational waves by its free oscillation in the first order
with respect to its oscillation amplitude, nevertheless the string actually
bends when the incidental gravitational waves go through it.

</DOC>
<DOC>
<DOCNO> 178845 </DOCNO>
Quark-Meson Coupling Model for a Nucleon


  The quark-meson coupling model for a nucleon is considered. The model
describes a nucleon as an MIT bag, in which quarks are coupled to scalar and
vector mesons. A set of coupled equations for the quark and the meson fields
are obtained and are solved in a self-consistent way. It is shown that the mass
of a nucleon as a dressed MIT bag interacting with sigma- and omega-meson
fields significantly differs from the mass of a free MIT bag. A few sets of
model parameters are obtained so that the mass of a dressed MIT bag becomes the
nucleon mass. The results of our calculations imply that the self-energy of the
bag in the quark-meson coupling model is significant and needs to be considered
in doing the nuclear matter calculations.

</DOC>
<DOC>
<DOCNO> 120635 </DOCNO>
Evolution of globular cluster systems in elliptical galaxies. I.


  We study the evolution of globular cluster systems (GCS) in elliptical
galaxies and explore the dependence of their main properties on the mass and
the size of the host galaxy.The dependence of the evolution of the GCS mass
function (GCMF), of the fraction of surviving clusters and of the ratio of the
final to initial mass in clusters on the structure of the host galaxy as well
as their variation with the galactocentric distance inside individual host
galaxies has been thoroughly investigated.After a survey over a large number of
different host galaxies we have restricted our attention to a sample of
galaxies with effective masses and radii equal to those observed for
dwarf,normal and giant ellipticals. We show that, in spite of large differences
in the fraction of surviving clusters, the final mean masses of the GCMF in
massive galaxies are very similar to each other with a small galaxy-to-galaxy
dispersion;low-mass compact galaxies tend to have smaller values of the final
mean mass and a larger galaxy-to-galaxy dispersion. These findings are in
agreement with those of recent observational analyses. The fraction of
surviving clusters increases with the mass of the host galaxy. We show that a
small difference between the initial and the final mean mass and dispersion of
the GCMF and the lack of a significant radial dependence of the mean mass
inside individual galaxies do not necessarily imply that evolutionary processes
have been unimportant in the evolution of the initial population of clusters.
For giant galaxies most disruption occurs within the effective radius while for
low-mass galaxies a significant disruption of clusters takes place also at
larger galactocentric distances. The dependence of the results obtained on the
initial mean mass of the GCMF is investigated. (abridged)

</DOC>
<DOC>
<DOCNO> 70997 </DOCNO>
Perturbative quark bound states in pNRQCD


  In the framework of the QCD effective field theory called potential
Non-Relativistic QCD, we explore quark-antiquark bound systems that may be
dominated by the perturbative interaction and we discuss the extent of validity
of such a picture. Some phenomenological implications are outlined.

</DOC>
<DOC>
<DOCNO> 151974 </DOCNO>
An alternative formulation of classical electromagnetic duality


  By introducing a doublet of electromagnetic four dimensional vector
potentials, we set up a manifestly Lorentz covariant and SO(2) duality
invariant classical field theory of electric and magnetic charges. In our
formulation one does not need to introduce the concept of Dirac string.

</DOC>
<DOC>
<DOCNO> 8836 </DOCNO>
One+Infinite Dimensional Attractor Neural Networks


  We solve a class of attractor neural network models with a mixture of 1D
nearest-neighbour and infinite-range interactions, which are of a Hebbian-type
form. Our solution is based on a combination of mean-field methods, transfer
matrices and 1D random-field techniques, and is obtained for Boltzmann-type
equilibrium (following sequential Glauber dynamics) and Peretto-type
equilibrium (following parallel dynamics). Competition between the alignment
forces mediated via short-range interactions, and those mediated via
infinite-range ones, is found to generate novel phenomena, such as multiple
locally stable `pure' states, first-order transitions between recall states,
2-cycles and non-recall states, and domain formation leading to extremely long
relaxation times. We test our results against numerical simulations and simple
benchmark cases and find excellent agreement.

</DOC>
<DOC>
<DOCNO> 70492 </DOCNO>
Precise nondivergent analytic formulas for the radiative corrections to


  Very accurate analytical expressions for the radiative corrections of
unpolarized hyperons semileptonic decays of charged and neutral baryons have
been obtained in the recent past. Some of these formulas contain logarithmic
singularities at the edges of the Dalitz plot for the three- and four-body
decays. These singularities are analyzed and integrated analytically to obtain
new divergentless formulas for the energy spectrum of the produced beta
particle. The new equations contain terms of the order alpha times the momentum
transfer, are applicable to any beta decay process and are suitable for a
model-independent experimental analysis.

</DOC>
<DOC>
<DOCNO> 117043 </DOCNO>
Noise Delays Bifurcation in a Positively Coupled Neural Circuit


  We report a noise induced delay of bifurcation in a simple pulse-coupled
neural circuit. We study the behavior of two neural oscillators, each
individually governed by saddle-node dynamics, with reciprocal excitatory
synaptic connections. In the deterministic circuit, the synaptic current
amplitude acts as a control parameter to move the circuit from a mono-stable
regime through a bifurcation into a bistable regime. In this regime stable
sustained anti-phase oscillations in both neurons coexist with a stable rest
state. We introduce a small amount of random current into both neurons to model
possible randomly arriving synaptic inputs. We find that such random noise
delays the onset of bistability, even though in decoupled neurons noise tends
to advance bifurcations and the circuit has only excitatory coupling. We show
that the delay is dependent on the level of noise and suggest that a curious
stochastic ``anti-resonance'' is present.

</DOC>
<DOC>
<DOCNO> 10355 </DOCNO>
Edge electron states for quasi-one-dimensional organic conductors in the


  We develop a microscopic picture of the electron states localized at the
edges perpendicular to the chains in the Bechgaard salts in the quantum Hall
regime. In a magnetic-field-induced spin-density-wave state (FISDW)
characterized by an integer N, there exist N branches of chiral gapless edge
excitations. Localization length is much longer and velocity much lower for
these states than for the edge states parallel to the chains. We calculate the
contribution of these states to the specific heat and propose a time-of-flight
experiment to probe the propagating edge modes directly.

</DOC>
<DOC>
<DOCNO> 102316 </DOCNO>
Polar and coisotropic actions on Kaehler manifolds


  The main result of this paper is that a polar action on a compact irreducible
homogeneous Kaehler manifold is coisotropic. This is then used to give new
examples of polar actions and to classify coisotropic and polar actions on
quadrics.

</DOC>
<DOC>
<DOCNO> 119495 </DOCNO>
An exploratory study of the hard X-ray variability properties of PG


  We have monitored with the RXTE PCA the variability pattern of the 2-20 keV
flux in four PG quasars (QSOs) from the Laor et al. (1994) sample. Six
observations of each target at regular intervals of 1 day were performed. The
sample comprises objects with extreme values of Balmer line width (and hence
soft X-ray steepness) and spans about one order of magnitude in luminosity. The
most robust result is that the variability amplitude decreases as energy
increases. Several options for a possible ultimate driver of the soft and hard
X-ray variability, such as the influx rate of Comptonizing relativistic
particles, instabilities in the accretion flow or the number of X-ray active
sites, are consistent with our results.

</DOC>
<DOC>
<DOCNO> 120413 </DOCNO>
Spectral Models of Convection-Dominated Accretion Flows


  For small values of the dimensionless viscosity parameter, namely
$\alpha\lesssim 0.1$, the dynamics of non-radiating accretion flows is
dominated by convection; convection strongly suppresses the accretion of matter
onto the central object and transports a luminosity $\sim 10^{-3}-10^{-2} \dot
M c^2$ from small to large radii in the flow. A fraction of this convective
luminosity is likely to be radiated at large radii via thermal bremsstrahlung
emission. We show that this leads to a correlation between the frequency of
maximal bremsstrahlung emission and the luminosity of the source, $\nu_{\rm
peak} \propto L^{2/3}$. Accreting black holes with X-ray luminosities $10^{-4}
L_{Edd}\gtrsim L_X(0.5-10{\rm keV}) \gtrsim 10^{-7}L_{Edd}$ are expected to
have hard X-ray spectra, with photon indices $\Gamma\sim2$, and sources with
$L_X\lesssim 10^{-9}L_{Edd}$ are expected to have soft spectra, with
$\Gamma\sim3.5$. This is testable with {\it Chandra} and {\it XMM}.

</DOC>
<DOC>
<DOCNO> 8946 </DOCNO>
Effects of spin-elastic interactions in frustrated Heisenberg


  The Heisenberg antiferromagnet on a compressible triangular lattice in the
spin- wave approximation is considered. It is shown that the interaction
between quantum fluctuations and elastic degrees of freedom stabilizes the low
symmetric L-phase with a collinear Neel magnetic ordering. Multi-stability in
the dependence of the on-site magnetization on an unaxial pressure is found.

</DOC>
<DOC>
<DOCNO> 81004 </DOCNO>
A Numerical Study of Spectral Flows of Hermitian Wilson-Dirac Operator


  We investigate the index of the Neuberger's Dirac operator in abelian gauge
theories on finite lattices by numerically analyzing the spectrum of the
hermitian Wilson-Dirac operator for a continuous family of gauge fields
connecting different topological sectors. By clarifying the characteristic
structure of the spectrum leading to the index theorem we show that the index
coincides to the topological charge for a wide class of gauge field
configurations. We also argue that the index can be found exactly for some
special but nontrivial configurations in two dimensions by directly analyzing
the spectrum.

</DOC>
<DOC>
<DOCNO> 10513 </DOCNO>
Structure of High Order Corrections to Lipatov's Asymptotics


  High orders of perturbation theory can be calculated by the Lipatov method,
whereby they are determined by saddle-point configurations (instantons) of the
corresponding functional integrals. For most field theories, the Lipatov
asymptotics has the functional form c a^N \Gamma(N+b) (N is the order of
perturbation theory), and the relative corrections to it have a form of a
series in powers of 1/N. It is shown that this series diverges factorially and
its high-order coefficients can be calculated using a procedure similar to
Lipatov's one. The K-th expansion coefficient has the form
const(\ln(S1/S0))^{-K}\Gamma(K+(r1-r0)/2), where S0 and S1 are the values of
the action for the first and the second instanton of the field theory under
consideration, while r0 and r1 are the corresponding numbers of zero modes. The
instantons satisfy the same equation as in the Lipatov method and are assumed
to be renumbered in order of increasing of their action. This result has the
universal character and is valid in any field theory for which the Lipatov
asymptotic form is as specified above.

</DOC>
<DOC>
<DOCNO> 70872 </DOCNO>
Glueball as a bound state in the selfdual homogeneous vacuum gluon field


  Using a simple relativistic QFT model of scalar fields we demonstrate that
the analytic confinement (propagator is an entire function in the complex
p^2-plane) and the weak coupling constant lead to the Regge behaviour of the
two-particle bound states. In QCD we assume that the gluon vacuum is realized
by the selfdual homogeneous classical field which is the solution of the
Yang-Mills equations. This assumption leads to analytical confinement of quarks
and gluons. We extract the colorless 0(++) two-glouon state from the QCD
generating functional in the one-gluon exchange approximation. The mass of this
bound state is defined by the Bethe-Salpeter equation. The glueball mass varies
in the region 1470{Mev} - 1600{Mev} for QCD coupling constant in the region 0.2
- 0.5 if the gluon condensate is 0.012 Gev^4.

</DOC>
<DOC>
<DOCNO> 72171 </DOCNO>
The Exact Renormalization Group and First-Order Phase Transitions


  Studies of first-order phase transitions through the use of the exact
renormalization group are reviewed. In the first part the emphasis is on
universal aspects: We discuss the universal critical behaviour near weakly
first-order phase transitions for a three-dimensional model of two coupled
scalar fields -- the cubic anisotropy model. In the second part we review the
application of the exact renormalization group to the calculation of
bubble-nucleation rates. More specifically, we concentrate on the
pre-exponential factor. We discuss the reliability of homogeneous nucleation
theory that employs a saddle-point expansion around the critical bubble for the
calculation of the nucleation rate.

</DOC>
<DOC>
<DOCNO> 80862 </DOCNO>
Reformulating Yang-Mills theory in terms of local gauge invariant


  An explicit canonical transformation is constructed to relate the physical
subspace of Yang-Mills theory to the phase space of the ADM variables of
general relativity. This maps 3+1 dimensional Yang-Mills theory to local
evolution of metrics on 3 manifolds.

</DOC>
<DOC>
<DOCNO> 174550 </DOCNO>
Direct Photon Production in 158 AGeV Pb+Pb Collisions


  A measurement of direct photon production in Pb+Pb collisions at 158 AGeV has
been carried out in the CERN WA98 experiment. The invariant yield of direct
photons in central collisions is extracted as a function of transverse momentum
in the interval 0.5 < pT < 4 GeV/c. A significant direct photon signal,
compared to statistical and systematical errors, is seen at pT > 1.5 GeV/c. The
results constitute the first observation of direct photons in ultrarelativistic
heavy-ion collisions which could be significant for diagnosis of quark gluon
plasma formation.

</DOC>
<DOC>
<DOCNO> 83352 </DOCNO>
Compact non-left-recursive grammars using the selective left-corner


  The left-corner transform removes left-recursion from (probabilistic)
context-free grammars and unification grammars, permitting simple top-down
parsing techniques to be used. Unfortunately the grammars produced by the
standard left-corner transform are usually much larger than the original. The
selective left-corner transform described in this paper produces a transformed
grammar which simulates left-corner recognition of a user-specified set of the
original productions, and top-down recognition of the others. Combined with two
factorizations, it produces non-left-recursive grammars that are not much
larger than the original.

</DOC>
<DOC>
<DOCNO> 68150 </DOCNO>
Heavy Flavour Production in Two-Photon Collisions


  We review the production of charm and bottom quarks in two-photon collisions
at e+e- colliders. The next-to-leading order QCD predictions for total cross
sections and differential distributions are compared with recent experimental
results.

</DOC>
<DOC>
<DOCNO> 151146 </DOCNO>
Open membranes in a constant C-field background and noncommutative


  We investigate the dynamics of open membrane boundaries in a constant C-field
background. We follow the analysis for open strings in a B-field background,
and take some approximations. We find that open membrane boundaries do show
noncommutativity in this case by explicit calculations. Membrane boundaries are
one dimensional strings, so we face a new type of noncommutativity, that is,
noncommutative strings.

</DOC>
<DOC>
<DOCNO> 13631 </DOCNO>
Fermi surface of Sr2RuO4 from angle resolved photoemission


  We investigated the low-energy electronic structure of Sr2RuO4 by
angle-resolved photoemission spectroscopy (ARPES) focusing, in particular, on
the controversial issues of the Fermi surface (FS) topology and of the extended
van Hove singularity (evHs). A detailed study of temperature and photon energy
dependence demonstrates the surface-state nature of the electronic band
responsible for the evHs, and may suggest the presence of ferromagnetic
correlations at the surface. In addition, we detected a replica of the primary
FS that indicates a (sqrt2 x sqrt2) surface reconstruction, as confirmed by
LEED. In light of these findings, the FS determined by ARPES is consistent with
LDA and de Haas-van Alphen (dHvA) results, and it provides additional
information on the detailed shape of the alpha, beta and gamma sheets. Also, at
this stage, because of the strong sensitivity of the cleaved surface, we could
not find any robust signature of the crossover from 2D to 3D Fermi liquid
behavior in our ARPES measurements for T<130 K.

</DOC>
<DOC>
<DOCNO> 99844 </DOCNO>
The compression theorem II: directed embeddings


  This is the second of three papers about the Compression Theorem. We give
proofs of Gromov's theorem on directed embeddings [M Gromov, Partial
differential relations, Springer--Verlag (1986); 2.4.5 C'] and of the Normal
Deformation Theorem [The compression theorem I; 4.7], arxiv:math.GT/9712235.

</DOC>
<DOC>
<DOCNO> 13717 </DOCNO>
Green's function probe of a static granular piling


  We present an experiment which aim is to investigate the mechanical
properties of a static granular assembly. The piling is an horizontal 3D
granular layer confined in a box, we apply a localized extra force at the
surface and the spatial distribution of stresses at the bottom is obtained (the
mechanical Green's function). For different types of granular media, we observe
a linear pressure response which profile shows one peak centered at the
vertical of the point of application. The peak's width increases linearly when
increasing the depth. This green function seems to be in -at least- qualitative
agreement with predictions of elastic theory.

</DOC>
<DOC>
<DOCNO> 11100 </DOCNO>
Slow plasmon modes in polymeric salt solutions


  The dynamics of polymeric salt solutions are presented. The salt consists of
chains $\rm A$ and $\rm B$, which are chemically different and interact with a
Flory-interaction parameter $\chi$, the $\rm A$ chain ends carry a positive
charge whereas the $\rm B$ chain ends are modified by negative charges. The
static structure factor shows a peak corresponding to a micro phase separation.
At low momentum transfer, the interdiffusion mode is driven by electrostatics
and is of the plasmon-type, but with an unusually low frequency, easily
accessible by experiments. This is due to the polymer connectivity that
introduces high friction and amplifies the charge scattering thus allowing for
low charge densities. The interdiffusion mode shows a minimum (critical slowing
down) at finite $k$ when the interaction parameter increases we find then a low
$k$ frequency quasi-plateau.

</DOC>
<DOC>
<DOCNO> 122951 </DOCNO>
Evolution of a Neutron Star From its Birth to Old Age


  The main stages in the evolution of a neutron star, from its birth as a
proto-neutron star, to its old age as a cold, catalyzed configuration, are
described. A proto-neutron star is formed in the aftermath of a successful
supernova explosion and its evolution is dominated by neutrino diffusion. Its
neutrino signal is a valuable diagnostic of its internal structure and
composition. During its transformation from a hot, lepton-rich to a cold,
catalyzed remnant, the possibility exists that it can collapse into a black
hole, which abruptly terminates neutrino emissions. The essential microphysics,
reviewed herein, that controls its evolution are the equation of state of dense
matter and its associated neutrino opacities. Several simulations of the
proto-neutron star evolution, involving different assumptions about the
composition of dense matter, are described. After its evolution into a nearly
isothermal neutron star a hundred or so years after its birth, it may be
observable through its thermal emission in X-rays during its life in the next
million years. Its surface temperature will depend upon the rapidity of
neutrino emission processes in its core, which depends on the composition of
dense matter and whether or not its constituents exhibit superfluidity and
superconductivity. Observations of thermal emission offer the best hope of a
determination of the radius of a neutron star. The implications for the
underlying dense matter equation of state of an accurate radius determination
are explored.

</DOC>
<DOC>
<DOCNO> 84938 </DOCNO>
Regular quantum interiors for black holes


  A family of spacetimes suitable for describing the interior of a
non-rotational black hole is constructed. The stress-energy tensor is that of a
spherically symmetric vacuum, as commonly assumed nowadays. The problem of
matching the exterior with the interior region is solved exactly, without using
any massive shell nor having to restrict oneself to only asymptotically
well-behaved solutions, whatsoever. The main physical and geometrical
properties of the resulting black hole solutions are described. As models for
the interior the general solution found includes, in particular, two known
previous atttempts at solving the problem. Finally, effective macroscopic
properties of the solution are linked with quantization issues of the
corresponding spacetime.

</DOC>
<DOC>
<DOCNO> 8435 </DOCNO>
Negative Pressure of Anisotropic Compressible Hall States : Implication


  Pressure, compressibility, and Hall conductance of anisotropic states at
higher Landau levels are computed. Pressure and compressibility become
negative. Hall conductance is unquantized and varies with filling factor. These
facts agree with the recent experimental observations of highly anisotropic
compressible states at higher Landau levels. It is shown, as an implication of
negative pressure, that the quantum Hall effect has extraordinary stability,
that is, Hall resistance is quantized even when the longitudinal resistance
does not vanish.

</DOC>
<DOC>
<DOCNO> 118244 </DOCNO>
A Study of the Populations of X-ray Sources in the Small Magellanic


  The Advanced Satellite for Cosmology and Astrophysics (ASCA) has made
multiple observations of the Small Magellanic Cloud (SMC). X-ray mosaic images
in the soft (0.7--2.0 keV) and hard (2.0--7.0 keV) bands are separately
constructed, and the latter provides the first hard X-ray view of the SMC. We
extract 39 sources from the two-band images with a criterion of S/N>5, and
conduct timing and spectral analyses for all of these sources. Coherent
pulsations are detected from 12 X-ray sources; five of which are new
discoveries. Most of the 12 X-ray pulsars are found to exhibit long-term flux
variabilities, hence they are likely to be X-ray binary pulsars (XBPs). On the
other hand, we classify four supernova remnants (SNRs) as thermal SNRs, because
their spectra exhibit emission lines from highly ionized atoms. We find that
XBPs and thermal SNRs in the SMC can be clearly separated by their hardness
ratio (the ratio of the count rate between the hard and soft bands). Using this
empirical grouping, we find many XBP candidates in the SMC, although no
pulsations have yet been detected from these sources. Possible implications on
the star-formation history and evolution of the SMC are presented by a
comparison of the source populations in the SMC and our Galaxy.

</DOC>
<DOC>
<DOCNO> 117156 </DOCNO>
Transition from reflection to sticking in ultracold atom-surface


  In paper I (physics/0010068) entitled "The No-sticking Effect in Ultra-cold
Collisions", we showed that under very general circumstances, atoms approaching
a surface will not stick as its incoming energy approaches zero. This is true
of either warm or cold surfaces. Here we explore the transition region from non
sticking to sticking as energy is increased. The key to understanding the
transition region is the WKB approximation and the nature of its breakdown.
Simple rules for understanding the rollover to higher energy, post-threshold
behavior, including analytical formulae for some asymptotic forms of the
attractive potential are presented. We discuss a practical example of
atom-surface pair in various substrate geometries. We also discuss the case of
low energy scattering from clusters.

</DOC>
<DOC>
<DOCNO> 84764 </DOCNO>
Nonthermal nature of extremal Kerr black holes


  Liberati, Rothman and Sonego have recently showed that objects collapsing
into extremal Reissner-Nordstrom black holes do not behave as thermal objects
at any time in their history. In particular, a temperature, and hence
thermodynamic entropy, are undefined for them. I demonstrate that the analysis
goes through essentially unchanged for Kerr black holes.

</DOC>
<DOC>
<DOCNO> 120803 </DOCNO>
ADONIS observations of the HD 100546 circumstellar dust disk


  We report here the first resolved images of the circumstellar dust disk
around the Pre-Main-Sequence star HD 100546. These near-infrared images were
obtained in J and short K bands with the adaptive optics system ADONIS at the
ESO observatory. A bright disk extending 2 arcsec (200 AU) far from the star
and viewed with an inclination with respect to the line of sight around 50
degrees is revealed by the observations. Using a simplified model of light
scattering, we find that the dust disk density peaks at a distance of 40 AU
from the star, and the FWHM of this dense ring is typically 20 AU. This type of
disk is believed to be a denser precursor of beta Pictoris-like main-sequence
disks. The structure of the disk is compared with the best known example of the
class of ``debris disks'', the disk surrounding beta Pictoris.

</DOC>
<DOC>
<DOCNO> 122729 </DOCNO>
The Digital Sky Project: Prototyping Virtual Observatory Technologies


  Astronomy is entering a new era as multiple, large area, digital sky surveys
are in production. The resulting datasets are truly remarkable in their own
right; however, a revolutionary step arises in the aggregation of complimentary
multi-wavelength surveys (i.e., the cross-identification of a billion sources).
The federation of these large datasets is already underway, and is producing a
major paradigm shift as Astronomy has suddenly become an immensely data-rich
field. This new paradigm will enable quantitatively and qualitatively new
science, from statistical studies of our Galaxy and the large-scale structure
in the universe, to discoveries of rare, unusual, or even completely new types
of astronomical objects and phenomena. Federating and then exploring these
large datasets, however, is an extremely challenging task. The Digital Sky
project was initiated with this task in mind and is working to develop the
techniques and technologies necessary to solve the problems inherent in
federating these large databases, as well as the mining of the resultant
aggregate data.

</DOC>
<DOC>
<DOCNO> 119059 </DOCNO>
A Flat Universe from High-Resolution Maps of the Cosmic Microwave


  The blackbody radiation left over from the Big Bang has been transformed by
the expansion of the Universe into the nearly isotropic 2.73K Cosmic Microwave
Background. Tiny inhomogeneities in the early Universe left their imprint on
the microwave background in the form of small anisotropies in its temperature.
These anisotropies contain information about basic cosmological parameters,
particularly the total energy density and curvature of the universe. Here we
report the first images of resolved structure in the microwave background
anisotropies over a significant part of the sky. Maps at four frequencies
clearly distinguish the microwave background from foreground emission. We
compute the angular power spectrum of the microwave background, and find a peak
at Legendre multipole $\ell_{peak}=(197 \pm 6)$, with an amplitude
$DT_{200}=(69 \pm 8)\mu K$. This is consistent with that expected for cold dark
matter models in a flat (euclidean) Universe, as favoured by standard
inflationary scenarios.

</DOC>
<DOC>
<DOCNO> 151980 </DOCNO>
Energy Momentum Tensor and Operator Product Expansion in Local Causal


  We derive new examples for algebraic relations of interacting fields in local
perturbative quantum field theory. The fundamental building blocks in this
approach are time ordered products of free (composed) fields. We give explicit
formulas for the construction of Poincare covariant ones, which were already
known to exist through cohomological arguments.
  For a large class of theories the canonical energy momentum tensor is shown
to be conserved. Classical theories without dimensionful couplings admit an
improved tensor that is additionally traceless. On the example of phi^4-theory
we discuss the improved tensor in the quantum theory. Its trace receives an
anomalous contribution due to its conservation.
  Moreover we define an interacting bilocal normal product for scalar theories.
This leads to an operator product expansion of two time ordered fields.

</DOC>
<DOC>
<DOCNO> 118135 </DOCNO>
A Test of the Collisional Dark Matter Hypothesis from Cluster Lensing


  Spergel & Steinhardt proposed the possibility that the dark matter particles
are self-interacting, as a solution to two discrepancies between the
predictions of cold dark matter models and the observations: first, the
observed dark matter distribution in some dwarf galaxies has large,
constant-density cores, as opposed to the predicted central cusps; and second,
small satellites of normal galaxies are much less abundant than predicted. The
dark matter self-interaction would produce isothermal cores in halos, and would
also expel the dark matter particles from dwarfs orbiting within large halos.
However, another inevitable consequence of the model is that halos should
become spherical once most particles have interacted. Here, I rule out this
model by the fact that the innermost regions of dark matter halos in massive
clusters of galaxies are elliptical, as shown by gravitational lensing and
other observations. The absence of collisions in the lensing cores of massive
clusters implies that any dark matter self-interaction is too weak to have
affected the observed density profiles in the dark-matter dominated dwarf
galaxies, or to have eased the destruction of dwarf satellites in galactic
halos. If $s_x$ is the cross section and $m_x$ the mass of the dark matter
particle, then $s_x/m_x < 10^{-25.5} \cm^2/\gev$.

</DOC>
<DOC>
<DOCNO> 119708 </DOCNO>
Detection of Lead in the Carbon-Rich, Very Metal-Poor Star LP625-44: A


  We report the detection of the Pb I 4057.8A line in the very metal-poor
([Fe/H]=-2.7), carbon-rich star, LP625-44. We determine the abundance of Pb
([Pb/Fe] = 2.65) and 15 other neutron-capture elements. The abundance pattern
between Ba and Pb agrees well with a scaled solar system s-process component,
while the lighter elements (Sr-Zr) are less abundant than Ba. The enhancement
of s-process elements is interpreted as a result of mass transfer in a binary
system from a previous AGB companion, an interpretation strongly supported by
radial velocity variations of this system.
  The detection of Pb makes it possible, for the first time, to compare model
predictions of s-process nucleosynthesis in AGB stars with observations of
elements between Sr and Pb. The Pb abundance is significantly lower than the
prediction of recent models (e.g., Gallino et al. 1998), which succeeded in
explaining the metallicity dependence of the abundance ratios of light
s-elements (Sr-Zr) to heavy ones (Ba-Dy) found in previously observed
s-process-enhanced stars. This suggests that one should either (a) reconsider
the underlying assumptions concerning the 13C-rich s-processing site
(13C-pocket) in the present models, or (b) investigate alternative sites of
s-process nucleosynthesis in very metal-poor AGB stars.

</DOC>
<DOC>
<DOCNO> 119459 </DOCNO>
Far Ultraviolet Spectroscopic Explorer Observations of the Supernova


  We report a Far Ultraviolet Spectroscopic Explorer satellite observation of
the supernova remnant N49 in the Large Magellanic Cloud, covering the 905 --
1187 A spectral region. A 30'' square aperture was used, resulting in a
velocity resolution of ~100 km/s. The purpose of the observation was to examine
several bright emission lines expected from earlier work and to demonstrate
diffuse source sensitivity by searching for faint lines never seen previously
in extragalactic supernova remnant UV spectra. Both goals were accomplished.
Strong emission lines of O VI 1031.9 A, 1037.6 A and C III 977.0 A were seen,
Doppler broadened to +/- 225 km/s and with centroids red-shifted to 350 km/s,
consistent with the LMC. Superimposed on the emission lines are absorptions by
C III and O VI 1031.9 at +260 km/s, which are attributed to warm and hot gas
(respectively) in the LMC. The O VI 1037.6 A line is more severely affected by
overlying interstellar and H2 absorption from both the LMC and our galaxy. N
III 989.8 A is not seen, but models indicate overlying absorption severely
attenuates this line. A number of faint lines from hot gas have also been
detected, many of which have never been seen in an extragalactic supernova
remnant spectrum.

</DOC>
<DOC>
<DOCNO> 119603 </DOCNO>
Infrared observations of serendipitous hard Chandra X-ray sources


  We present observations of a sample of optically-faint, hard X-ray sources of
the kind likely to be responsible for much of the hard X-ray background. We
confirm that such sources are easily detected in the near-infrared, and find
that they have a featureless continuum suggesting that the active nucleus is
heavily obscured. The infrared colours of the majority of the targets observed
are consistent with absorbed elliptical host galaxies at z=1-2. It is likely
that we are observing some of the brighter members of the important new class
of X-ray Type II quasars.

</DOC>
<DOC>
<DOCNO> 101262 </DOCNO>
Cancellation of factorials


  We study the arithmetic property which allows to sharpen number-theoretic
estimates. Previous results on this property are, as a rule, quantitive. The
application of our general qualitive theorems to generalized hypergeometric
functions extends the set of irrational numbers which are the values of these
functions.

</DOC>
<DOC>
<DOCNO> 84898 </DOCNO>
Quantized Einstein-Rosen waves, AdS_2, and spontaneous symmetry breaking


  4D cylindrical gravitational waves with aligned polarizations (Einstein-Rosen
waves) are shown to be described by a weight 1/2 massive free field on the
double cover of AdS_2. Thorn's C-energy is one of the sl(2,R) generators, the
reconstruction from the (timelike) symmetry axis is the CFT_1 holography.
Classically the phase space is also invariant under a O(1,1) group action on
the metric coefficients that is a remnant of the original 4D diffeomorphism
invariance. In the quantum theory this symmetry is found to be spontaneously
broken while the AdS_2 conformal invariance remains intact.

</DOC>
<DOC>
<DOCNO> 71733 </DOCNO>
The masses of the mesons and baryons. Part IV. Integer multiple rule


  It is shown that the empirical rule that the masses of the stable mesons and
baryons of the gamma-branch are integer multiples of the mass of the pi0 meson
with a maximal deviation of 3.3% holds also for the meson and baryon
resonances, regardless whether the spin of the particles is 0 or 1/2. It is
also shown that the masses of the particles with weak decay are integer
multiples of the mass of the charged mesons times a common factor 0.853.

</DOC>
<DOC>
<DOCNO> 80990 </DOCNO>
Kosterlitz-Thouless theory and lattice artifacts


  The massive continuum limit of the 1+1 dimensional O(2) nonlinear
$\sigma$-model (XY model) is studied using its equivalence to the Sine-Gordon
model at its asymptotically free point. It is shown that leading lattice
artifacts are universal but they vanish only as inverse powers of the logarithm
of the correlation length. Such leading artifacts are calculated for the case
of the scattering phase shifts and the correlation function of the Noether
current using the bootstrap S-matrix and perturbation theory respectively.

</DOC>
<DOC>
<DOCNO> 99313 </DOCNO>
Maslov class and minimality in Calabi-Yau manifolds


  Generalizing the construction of the Maslov class for a Lagrangian embedding
in a symplectic vector space, we prove that it is possible to give a consistent
definition of this class for any Lagrangian submanifold of a Calabi-Yau
manifold. Moreover, we prove that this class can be represented by the
contraction of the Kaehler form associated to the Calabi-Yau metric, with the
mean curvature vector field of the Lagrangian embedding. Finally, we suggest a
possible generalization of the Maslov class for Lagrangian submanifolds of any
symplectic manifold, via the mean curvature representation.

</DOC>
<DOC>
<DOCNO> 71847 </DOCNO>
The m->0 limit for massive graviton in dS_4 and AdS_4. How to circumvent


  We show that, by considering physics in dS_4 or AdS_4 spacetime, one can
circumvent the van Dam - Veltman - Zakharov theorem which requires that the
extra polarization states of a massive graviton do not decouple in the massless
limit. It is shown that the smoothness of the m->0 limit is ensured if the H
(``Hubble'') parameter, associated with the horizon of the dS_4 or AdS_4 space,
tends to zero slower than the mass of the graviton m.

</DOC>
<DOC>
<DOCNO> 80998 </DOCNO>
Physical Results from Partially Quenched Simulation


  We describe how one can use chiral perturbation theory to obtain results for
physical quantities, such as quark masses, using partially quenched
simulations.

</DOC>
<DOC>
<DOCNO> 69532 </DOCNO>
The Earth Regeneration Effect of Solar Neutrinos: a Numerical Treatment


  We introduce an integrated algorithm for full scale investigation of the
earth regeneration effect of solar neutrinos with all three active neutrinos.
We illustrate that the earth effect on low energy solar neutrinos ($E_\nu < 20$
MeV) causes large variations in the survival probabilities for large values of
the mixing angle $\theta_{12}$ for a given value of $\theta_{13}$. But it is
maximal for small values of $\theta_{13}$ and diminishes for large values at a
given value of $\theta_{12}$. The nadir angle dependence is sensitive to the
value of $E'\equiv E/\Delta_{12}$. As far as low energy solar neutrinos are
concerned we notice that the earth effect is more pronounced for core
penetration. We confirm that the earth effect leaves the SMA region almost
intact regardless of $\theta_{13}$ and that it is significant for high energy
$^8$B and $hep$ neutrinos in the LMA region. We also show that for large values
of $\theta_{13}$, the earth effect is significant for high energy neutrinos
($E'\gtrsim 10^9$) and it can be large at any nadir angle.

</DOC>
<DOC>
<DOCNO> 117877 </DOCNO>
The Mass-To-Light Function: Antibias and Omega_m


  We use large-scale cosmological simulations to estimate the mass-to-light
ratio of galaxy systems as a function of scale, and compare the results with
observations of galaxies, groups, clusters, and superclusters of galaxies. We
find remarkably good agreement between observations and simulations.
Specifically, we find that the simulated mass-to-light ratio increases with
scale on small scales and flattens to a constant value on large scales, as
suggested by observations. We find that while mass typically follows light on
large scales, high overdensity regions --- such as rich clusters and
superclusters of galaxies --- exhibit higher M/L_B values than average, while
low density regions exhibit lower M/L_B values; high density regions are thus
antibiased in M/L_B, with mass more strongly concentrated than blue light. This
is true despite the fact that the galaxy mass density is unbiased or positively
biased relative to the total mass density in these regions. The M/L_B antibias
is likely due to the relatively old age of the high density regions, where
light has declined significantly since their early formation time, especially
in the blue band which traces recent star formation. Comparing the simulated
results with observations, we place a powerful constraint on the mass density
of the universe; using, for the first time, the entire observed mass-to-light
function, from galaxies to superclusters, we find Omega =0.16+/-0.05.

</DOC>
<DOC>
<DOCNO> 117727 </DOCNO>
OGLE Cepheids have Lower Amplitudes in SMC than in LMC


  We selected cepheids from the OGLE database for the Magellanic Clouds in the
period range 10^{1.1} < P < 10^{1.4} days. There were 33 objects in the LMC and
35 in the SMC. We find that the median amplitude of cepheids in the LMC is 18%
larger than in the SMC, a 4 sigma effect. This implies that the period - flux
amplitude relation is not universal, and cannot be used to measure distances
accurately.

</DOC>
<DOC>
<DOCNO> 170409 </DOCNO>
A two-slit experiment which distinguishes between standard and Bohmian


  In this investigation, we have suggested a special two-slit experiment which
can distinguish between the standard and the Bohmian quantum mechanics. At the
first step, we have shown that observable individual predictions obtained from
these two theories are inconsistent for a special case. But, at the ensemble
level, they are consistent as was expected. Then, as another special case and
using selective detection, it is shown that an observable disagreement between
the two theories can exist at the ensemble level of particles. This can
encourage new efforts for finding other inconsistencies between the two
theories, theoretically and experimentally.

</DOC>
<DOC>
<DOCNO> 121562 </DOCNO>
Shocks and Nonthermal Processes in Clusters


  Clusters of galaxies generally form by the gravitational merger of smaller
clusters and groups. Major cluster mergers are the most energetic events in the
Universe since the Big Bang. Mergers drive shocks into the intracluster gas,
and these shocks heat the intracluster gas, and should also accelerate
nonthermal relativistic particles. The X-ray signatures of the thermal effects
of merger shocks will be discussed. X-ray observations of shocks can be used to
determine the geometry and kinematics of the merger. As a result of particle
acceleration in shocks, clusters of galaxies should contain very large
populations of relativistic electrons and ions. Electrons with Lorentz factors
gamma~300 (energies E = gamma m_e c^2 ~ 150 MeV) are expected to be
particularly common. Observations and models for the radio, extreme
ultraviolet, hard X-ray, and gamma-ray emission from nonthermal particles
accelerated in these shocks will also be described. The predicted gamma-ray
fluxes of clusters should make them easily observable with GLAST.

</DOC>
<DOC>
<DOCNO> 123106 </DOCNO>
Multi-Color Observations of the GRB000926 Afterglow


  We present multi-color light-curves of the optical afterglow of GRB 000926.
Beginning ~1.5 days after the burst, the light-curves of this GRB steepen
measurably. The existence of such achromatic breaks are usually taken to be an
important observational signature that the ejecta are not expanding
isotropically, but rather have a collimated jet-like geometry. If we interpret
the data in this context, we derive an opening angle of 5 degrees, which
reduces the energy release compared to an isotropic model by a factor of ~275,
to 1.7 x 10^51 erg. To fit the data with a simple jet model requires extinction
along the line of sight. The derived A_V is in the range 0.11 - 0.82 mag,
depending on the adopted extinction law and whether the electrons giving rise
to the optical emission are undergoing synchrotron cooling or not. Since this
is in excess of the expected extinction from our Galaxy, we attribute this to
the GRB host. We note that this extinction is typical of a galactic disk, and
therefore the event likely took place in the disk of its host.

</DOC>
<DOC>
<DOCNO> 102558 </DOCNO>
Subalgebras of bigraded Koszul algebras


  We show that diagonal subalgebras and generalized Veronese subrings of a
bigraded Koszul algebra are Koszul. We give upper bounds for the regularity of
sidediagonal and relative Veronese modules and apply the results to symmetric
algebras and Rees rings.

</DOC>
<DOC>
<DOCNO> 121497 </DOCNO>
VLT spectroscopy of GRB 990510 and GRB 990712; probing the faint and


  We present time-resolved optical spectroscopy of the afterglows of the
gamma-ray bursts GRB 990510 and GRB 990712. Through the identification of
several absorption lines in the first epoch GRB 990510 spectrum, we determine
the redshift for this burst at z >= 1.619. No clear emission lines are
detected. The strength of the MgI feature is indicative of a dense environment,
most likely the host galaxy of GRB 990510. Although the host is extremely faint
(V >~ 28), the GRB afterglow allows us to probe its interstellar medium and -
in principle - to measure its metallicity. The optical spectrum of GRB 990712
(whose host galaxy is the brightest of the known GRB hosts at cosmological
redshifts), shows clear features both in emission and absorption, at a redshift
of z = 0.4331 +/- 0.0004. On the basis of several line emission diagnostic
diagrams, we conclude that the host galaxy of GRB 990712 is most likely an HII
galaxy. We derive a unreddened [OII] star formation rate of 2.7 +/- 0.8
Msun/yr. Correcting for the measured extinction intrinsic to the host galaxy
(A(V) = \gpm{3.4}{2.4}{1.7}), this value increases to \gpm{35}{178}{25}
Msun/yr. The [OII] equivalent width, compared to that of field galaxies at z <=
1, also suggests that the host of GRB 990712 is vigorously forming stars. We
employ the oxygen and Hbeta emission-line intensities to estimate the global
oxygen abundance for the host of GRB 990712: log(O/H) = -3.7 +- 0.4, which is
slightly below the lowest metallicity one finds in nearby spiral galaxies. For
both GRBs we study the time evolution of the absorption lines, whose equivalent
width might be expected to change with time if the burst resides in a dense
compact medium. We find no evidence for a significant change in the MgII width.

</DOC>
<DOC>
<DOCNO> 80864 </DOCNO>
Relativistic Quarkonia from Anisotropic Lattices


  We report on new results for the spectrum of quarkonia using a fully
relativistic approach on anisotropic lattices with quark masses in the range
from strange to bottom. A fine temporal discretisation also enables us to
resolve excitations high above the ground state. In particular we studied the
mass dependence and scaling of hybrid states.

</DOC>
<DOC>
<DOCNO> 169752 </DOCNO>
Casimir force at both non-zero temperature and finite conductivity


  We find the joint effect of non-zero temperature and finite conductivity onto
the Casimir force between real metals. Configurations of two parallel plates
and a sphere (lens) above a plate are considered. Perturbation theory in two
parameters (the relative temperature and the relative penetration depth of zero
point oscillations into the metal) is developed. Perturbative results are
compared with computations. Recent evidence concerning possible existence of
large temperature corrections at small separations between the real metals is
not supported.

</DOC>
<DOC>
<DOCNO> 84382 </DOCNO>
Scalar field cosmology in three-dimensions


  We study an analytical solution to the Einstein's equations in
2+1-dimensions. The space-time is dynamical and has a line symmetry. The matter
content is a minimally coupled, massless, scalar field. Depending on the value
of certain parameters, this solution represents three distinct space-times. The
first one is flat space-time. Then, we have a big bang model with a negative
curvature scalar and a real scalar field. The last case is a big bang model
with event horizons where the curvature scalar vanishes and the scalar field
changes from real to purely imaginary.

</DOC>
<DOC>
<DOCNO> 71608 </DOCNO>
Bounds on transverse momentum dependent distribution functions


  When more than one hadron takes part in a hard process, an extended set of
quark distribution and fragmentation functions becomes relevant. In this talk,
the derivation of Soffer-like bounds for these functions, in the case of a
spin-1/2 target, is sketched and some of their aspects are discussed.

</DOC>
<DOC>
<DOCNO> 70671 </DOCNO>
Quantum Dissipative Effects and Neutrinos : current constraints and


  We establish the most stringent experimental constraints coming from recent
terrestrial neutrino experiments on quantum mechanical decoherence effects in
neutrino systems. Taking a completely phenomenological approach, we probe
vacuum oscillations plus quantum decoherence between two neutrino species in
the channels $\nu_\mu \to \nu_\tau$, $\nu_\mu \to \nu_e$ and $\nu_e \to
\nu_\tau$, admitting that the quantum decoherence parameter $\gamma$ is related
to the neutrino energy $E_\nu$ as : $\gamma=\gamma_0 (E_\nu/\text{GeV})^{n}$,
with $n=-1,0,1$ and 2. Our bounds are valid for a neutrino mass squared
difference compatible with the atmospheric, the solar and, in many cases, the
LSND scale. We also qualitatively discuss the perspectives of the future long
baseline neutrino experiments to further probe quantum dissipation.

</DOC>
<DOC>
<DOCNO> 150329 </DOCNO>
Boundary states in Gepner models


  We extend the construction of the boundary states in Gepner models to the
non-diagonal modular invariant theories, and derive the same supersymmetric
conditions as the diagonal theories. We also investigate the relation between
the microscopic charges of the boundary states and Ramond charges of the B-type
D-branes on the Calabi-Yau threefolds with one K\"ahler modulus in the large
volume limit.

</DOC>
<DOC>
<DOCNO> 102363 </DOCNO>
Regularity of the Density of Surface States


  We prove that the integrated density of surface states of continuous or
discrete Anderson-type random Schroedinger operators is a measurable locally
integrable function rather than a signed measure or a distribution. This
generalize our recent results on the existence of the integrated density of
surface states in the continuous case and those of A. Chahrour in the discrete
case. The proof uses the new $L^p$-bound on the spectral shift function
recently obtained by Combes, Hislop, and Nakamura. Also we provide a simple
proof of their result on the Hoelder continuity of the integrated density of
bulk states.

</DOC>
<DOC>
<DOCNO> 11155 </DOCNO>
Many-body interactions among adsorbed atoms and molecules within carbon


  This paper assesses the importance of three-body triple dipole interactions
for quasi-one dimensional phases of He, Ne, H_2, Ar, Kr and Xe confined within
interstitial channels or on the external surfaces of nanotube bundles. We find
the substrate-mediated contribution to be substantial: for interstitial H_2 the
well depth of the effective pair potential is reduced to approximately one half
of its value in free space.
  We carry out ab initio calculations on linear and equilateral configurations
of H_2 trimer and find that overlap interactions do not greatly change the DDD
interaction in the linear configuration when the spacing is greater than about
3 A. However, the DDD interaction alone is clearly insufficient for the
triangular configurations studied.

</DOC>
<DOC>
<DOCNO> 119687 </DOCNO>
The influence of inverse Compton scattering on GRB afterglows: one


  The fireball model of gamma-ray bursts predicted that when the energetic
blast wave encountered the surrounding medium, there will be afterglow
emission, and the subsequent afterglow observations appeared to confirm this
prediction. In this simplest fireball model, the electrons have been
accelerated to a power law energy distribution in a relativistic blast wave,
then they give afterglow emission through synchrotron radiation. Up to now
synchrotron radiation is believed to be the main mechanism of GRB emission,
however, here we will show that under some circumstances, the inverse Compton
scattering (ICS) may play an important role, and can change the light curves of
GRB afterglows. Here we investigate the effects of ICS in the relativistic case
(the surrounding medium density $\rho \propto r^{-2}$) and in the
non-relativistic case (for both $\rho =constant$ and $\rho \propto r^{-2}$), we
find that in the relativistic case the effect of ICS is usually important,
while in the non-relativistic case, this effect is usually unimportant, unless
the surrounding medium density is very high. We show that if ICS is important,
then it can flatten and steepen the light curves of GRB afterglows, and this
may provide the explanation for some afterglow observations.

</DOC>
<DOC>
<DOCNO> 178405 </DOCNO>
Shell model description of normal parity bands in odd-mass heavy


  The low-energy spectra and B(E2) electromagnetic transition strengths of
159Eu, 159Tb and 159Dy are described using the pseudo SU(3) model. Normal
parity bands are built as linear combinations of SU(3) states, which are the
direct product of SU(3) proton and neutron states with pseudo spin zero (for
even number of nucleons) and pseudo spin 1/2 (for odd number of nucleons). Each
of the many-particle states have a well-defined particle number and total
angular momentum. The Hamiltonian includes spherical Nilsson single-particle
energies, the quadrupole-quadrupole and pairing interactions, as well as three
rotor terms which are diagonal in the SU(3) basis. The pseudo SU(3) model is
shown to be a powerful tool to describe odd-mass heavy deformed nuclei.

</DOC>
<DOC>
<DOCNO> 116689 </DOCNO>
On the Nature of Relativistic Phenomena


  Based upon the aberration of starlight, an attempt is made to explain the
experimental facts of importance concerning the special theory of relativity.
It is demonstrated that the classical concepts of time and the speed of light,
in contrast to the currently accepted view, are rather natural for describing
the physics of relativistic phenomena. Physics, rather than mathematics, is the
center of attention in this review.

</DOC>
<DOC>
<DOCNO> 84201 </DOCNO>
How does the electromagnetic field couple to gravity, in particular to


  The coupling of the electromagnetic field to gravity is an age-old problem.
Presently, there is a resurgence of interest in it, mainly for two reasons: (i)
Experimental investigations are under way with ever increasing precision, be it
in the laboratory or by observing outer space. (ii) One desires to test out
alternatives to Einstein's gravitational theory, in particular those of a
gauge-theoretical nature, like Einstein-Cartan theory or metric-affine gravity.
A clean discussion requires a reflection on the foundations of electrodynamics.
If one bases electrodynamics on the conservation laws of electric charge and
magnetic flux, one finds Maxwell's equations expressed in terms of the
excitation H=(D,H) and the field strength F=(E,B) without any intervention of
the metric or the linear connection of spacetime. In other words, there is
still no coupling to gravity. Only the constitutive law H= functional(F)
mediates such a coupling. We discuss the different ways of how metric,
nonmetricity, torsion, and curvature can come into play here. Along the way, we
touch on non-local laws (Mashhoon), non-linear ones (Born-Infeld,
Heisenberg-Euler, Plebanski), linear ones, including the Abelian axion (Ni),
and find a method for deriving the metric from linear electrodynamics (Toupin,
Schoenberg). Finally, we discuss possible non-minimal coupling schemes.

</DOC>
<DOC>
<DOCNO> 81008 </DOCNO>
Low-Energy Effective Theories of Quantum Link and Quantum Spin Models


  Quantum spin and quantum link models provide an unconventional regularization
of field theory in which classical fields arise via dimensional reduction of
discrete variables. This D-theory regularization leads to the same continuum
theories as the conventional approach. We show this by deriving the low-energy
effective Lagrangians of D-theory models using coherent state path integral
techniques. We illustrate our method for the $(2+1)$-d Heisenberg quantum spin
model which is the D-theory regularization of the 2-d O(3) model. Similarly, we
prove that in the continuum limit a $(2+1)$-d quantum spin model with
$SU(N)_L\times SU(N)_R\times U(1)_{L=R}$ symmetry is equivalent to the 2-d
principal chiral model. Finally, we show that $(4+1)$-d SU(N) quantum link
models reduce to ordinary 4-d Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 8230 </DOCNO>
Enhancement of persistent currents due to confinement in metallic


  Confinement and surface roughness (SR) effects on the magnitude of the
persistent current are analized for ballistic bidimensional metallic samples.
Depending on the particular geometry, localized border states can show up at
half filling. These border states contribute coherently to the persistent
current and its magnitude is enhanced with respect to their value in the absent
of confinement. A linear scaling of the typical current $I_{typ}$ with the
number of conduction channels M is obtained. This result is robust with respect
to changes in the relevant lengths of the samples and to the SR. Possible links
of our results to experiments are also discussed.

</DOC>
<DOC>
<DOCNO> 71043 </DOCNO>
Pade-Improved Estimate of Perturbative Contributions to Inclusive


  Pade-approximant methods are used to estimate the three-loop perturbative
contributions to the inclusive semileptonic $b \to u$ decay rate. These
improved estimates of the decay rate reduce the theoretical uncertainty in the
extraction of the CKM matrix element $|V_{ub}|$ from the measured inclusive
semileptonic branching ratio.

</DOC>
<DOC>
<DOCNO> 178486 </DOCNO>
Compton scattering in a unitary approach with causality constraints


  Pion-loop corrections for Compton scattering are calculated in a novel
approach based on the use of dispersion relations in a formalism obeying
unitarity. The basic framework is presented, including an application to
Compton scattering. In the approach the effects of the non-pole contribution
arising from pion dressing are expressed in terms of (half-off-shell) form
factors and the nucleon self-energy. These quantities are constructed through
the application of dispersion integrals to the pole contribution of loop
diagrams, the same as those included in the calculation of the amplitudes
through a K-matrix formalism. The prescription of minimal substitution is used
to restore gauge invariance. The resulting relativistic-covariant model
combines constraints from unitarity, causality, and crossing symmetry.

</DOC>
<DOC>
<DOCNO> 118923 </DOCNO>
Identification and astrometry of variables in M3


  We present identification and astrometry of all previously known or suspected
variables along with the discovery of six new variables in the globular cluster
M3. The number of the catalogized variables increased to 274 by including all
the confirmed, previously known variables and the new discoveries. The precise
and homogeneous astrometry, as well as the clarification of misapprehensions in
the preceding identifications are done by using overlapping fields from a
wide-field Schmidt-camera, a 1m RCC telescope, and HST archive observations
from the center of the cluster. The astrometric positions can serve as a direct
input to any photometry which needs the accurate centers of the variables.

</DOC>
<DOC>
<DOCNO> 11926 </DOCNO>
Branched Polymers and Percolation


  We study a supposed model for branched polymers which was shown in two
dimensions to be in the universality class of ordinary percolation. We confirm
this by high statistics simulations and show that it is in the percolation
universality class also for three dimensions, in contrast to previous claims.
These previous studies seem to have been mislead by huge corrections to scaling
in this model.

</DOC>
<DOC>
<DOCNO> 83120 </DOCNO>
A Comparison of Logic Programming Approaches for Representation and


  Many logic programming based approaches can be used to describe and solve
combinatorial search problems. On the one hand there are definite programs and
constraint logic programs that compute a solution as an answer substitution to
a query containing the variables of the constraint satisfaction problem. On the
other hand there are approaches based on stable model semantics, abduction, and
first-order logic model generation that compute solutions as models of some
theory. This paper compares these different approaches from point of view of
knowledge representation (how declarative are the programs) and from point of
view of performance (how good are they at solving typical problems).

</DOC>
<DOC>
<DOCNO> 100550 </DOCNO>
On some automorphisms of the set of effects on Hilbert space


  The set of all efects on a Hilbert space has an affine structure (it is a
convex set) as well as a multiplicative structure (it can be equipped with the
so-called Jordan triple product). In this paper we describe the corresponding
automorphisms of that set.

</DOC>
<DOC>
<DOCNO> 151335 </DOCNO>
A note on D-branes in group manifolds: flux quantisation and D0-charge


  We show that a D-brane in a group manifold given by a (twisted) conjugacy
class is characterised by a gauge invariant two-form field determined in terms
of the matrix of gluing conditions. Using a quantisation argument based on the
path integral one obtains the known quantisation condition for the
corresponding D-branes. We find no evidence for the existence of a quantised
U(1) gauge field flux. We propose an expression for the D0 charge of such
 D-branes.

</DOC>
<DOC>
<DOCNO> 69872 </DOCNO>
Squark Loop Correction to W^{+-} H^{-+} Associated Hadroproduction


  We study the squark loop correction to W^{+-} H^{-+} associated
hadroproduction via gluon-gluon fusion within the minimal supersymmetric
extension of the standard model. We list full analytic results and
quantitatively analyze the resulting shift in the cross section at the CERN
Large Hadron Collider assuming a supergravity-inspired scenario.

</DOC>
<DOC>
<DOCNO> 40653 </DOCNO>
Status of the LHCb Experiment


  We present the status of the LHCb experiment which will make precision
measurements of CP violation in $B$ meson decays. The motivation for the
experiment and an overview of the detector design are given. The vertex
detector, ring imaging Cherenkov counter, calorimeters, and trigger systems are
discussed in detail. We also present the expected physics performance for
selected modes.

</DOC>
<DOC>
<DOCNO> 85266 </DOCNO>
General Relativity as a (constrained) Yang-Mills's Theory and a Novel


  We show that General Relativity (GR) with cosmological constant may be
formulated as a rather simple constrained SO(D-1,2) (or SO(D,1))-Yang-Mills
(YM) theory. Furthermore, the spin connections of the Cartan-Einstein
formulation for GR appear as solutions of a genuine SO(D-1,1)-YM.
  We also present a theory of gravity with torsion as the most natural
extension of this result. The theory comes out to be strictly an YM-theory upon
relaxation of a suitable constraint. This work sets out to enforce the close
connection between YM theories and GR by means of a new construction.

</DOC>
<DOC>
<DOCNO> 68711 </DOCNO>
Forward jets in the colour-dipole model


  We show that a forward jet with large transverse momentum in an onium-onium
collision is a hard probe which can be effectively characterized by a colour-
dipole distribution at the time of the interaction. The dipole distribution is
computed, and compared to its counterpart for a virtual photon in the initial
state. We find that while in the photon case, the tail of large sizes is
exponentially cut-off, it contributes sizeably in the forward-jet case, which
signs the sensitivity of observables based on such events to the infrared
region. Moreover, a direct probabilistic interpretation of the dipole
distribution fails since it takes negative values in the large size region.

</DOC>
<DOC>
<DOCNO> 70807 </DOCNO>
Non Abelian Gauge Couplings in Four Fermion Processes at LEP


  The LEP data on four fermion processes are presently used to study the non
abelian gauge couplings of the Standard Model. The present theoretical error
for two classes of processes, single-W production and radiative four fermion
final states, is discussed according to the results of the four fermion working
group of the LEP2 Monte Carlo Workshop held at CERN.

</DOC>
<DOC>
<DOCNO> 100292 </DOCNO>
The Geometry of Bundle Gerbes


  This thesis reviews the theory of bundle gerbes and then examines the higher
dimensional notion of a bundle 2-gerbe. The notion of a bundle 2-gerbe
connection and 2-curving are introduced and it is shown that there is a class
in $H^{4}(M;\Z)$ associated to any bundle 2-gerbe.

</DOC>
<DOC>
<DOCNO> 120299 </DOCNO>
The Galactic disk: study of four low latitude Galactic Fields


  We present deep V and I photometry of stellar field in four previously
unstudied low latitude regions of the Galactic disk. All observed fields are
located at the western side of the Galactic Center in the direction of the
Coalsack-Carina region. Two of them are suspected to cross the inner spiral
arm. More than $10^5$ stars are detected in total, down to a magnitude of V
$\sim 23.5$.
 Due to the low galactic latitude of the studied fields, the scale length and
mainly the scale height of the thick disk are not strongly constrained by the
observations. However a thin disk scale height of about
 250$\pm 60$ pc seems to be favored. The data are very sensitive to the star
formation rate of the thin disk. A decreasing star formation rate (SFR) is
necessary to reproduce the distribution of the stars in the colour-magnitude
diagrams (CMDs) as well as the luminosity functions. A constant or a strongly
increasing SFR as derived using Hipparcos data for the solar neighborhood
(Bertelli et al 1999) are marginally in agreement with the luminosity functions
but they are at odds with the CMDs. The analysis of these data suggest that the
solar neighborhood SFR cannot be considered as representative for the whole
thin disk. From the star-counts the local neighborhood mass density in stars
more massive than 0.1 M$_\odot$ is found to be 0.036--0.02 M$_\odot$ pc$^{-3}$.
Finally, the location of inner spiral arm is discussed. We find evidence of a
population younger than 10$^8$ yr distributed in a spiral arm at a distance of
1.3$\pm 0.2$ and 1.5 $\pm 0.2$\,Kpc in the directions l$\sim$\,292 and
l$\sim$\,305 respectively. This result is consistent with the spiral arm
pattern defined on the basis of pulsars and young associations.

</DOC>
<DOC>
<DOCNO> 152198 </DOCNO>
An Exact Prediction of N=4 SUSYM Theory for String Theory


  We propose that the expectation value of a circular BPS-Wilson loop in N=4
SUSYM can be calculated exactly, to all orders in a 1/N expansion and to all
orders in g^2 N. Using the AdS/CFT duality, this result yields a prediction of
the value of the string amplitude with a circular boundary to all orders in
alpha' and to all orders in g_s. We then compare this result with string
theory. We find that the gauge theory calculation, for large g^2 N and to all
orders in the 1/N^2 expansion does agree with the leading string theory
calculation, to all orders in g_s and to lowest order in alpha'. We also find a
relation between the expectation value of any closed smooth Wilson loop and the
loop related to it by an inversion that takes a point along the loop to
infinity, and compare this result, again successfully, with string theory.

</DOC>
<DOC>
<DOCNO> 70087 </DOCNO>
Brane world from IIB matrices


  We have recently proposed a dynamical mechanism that may realize a flat
four-dimensional space time as a brane in type IIB superstring theory. A
crucial role is played by the phase of the chiral fermion integral associated
with the IKKT Matrix Theory, which is conjectured to be a nonperturbative
definition of type IIB superstring theory. We demonstrate our mechanism by
studying a simplified model, in which we find that a lower-dimensional brane
indeed appears dynamically. We also comment on some implications of our
mechanism on model building of the brane world.

</DOC>
<DOC>
<DOCNO> 80984 </DOCNO>
Thermodynamics of free domain wall and overlap fermions


  Studies of non-interacting lattice fermions give an estimate of the size of
discretization errors and finite size effects for more interesting problems
like finite temperature QCD. We present a calculation of the thermodynamic
equation of state for free domain wall and overlap fermions.

</DOC>
<DOC>
<DOCNO> 10075 </DOCNO>
Modelling structural relaxation in polymeric glasses using the


  Governing equations are derived for the kinetics of physical aging in
polymeric glasses. An amorphous polymer is treated as an ensemble of
cooperatively rearranged regions (CRR). Any CRR is thought of as a string of
elementary clusters (EC). Fragmentation of the string may occur at random time
at any border between ECs. Two string can aggregate at random time to produce a
new string. The processes of aggregation and fragmentation are treated as
thermally activated, and the rate of fragmentation is assumed to grow with
temperature more rapidly than that for coalescence. This implies that only
elementary clusters are stable at the glass transition temperature, whereas
below this temperature, CRRs containing several ECs remain stable as well. A
nonlinear differential equation is developed for the distribution of CRRs with
various numbers of ECs. Adjustable parameters of the model are found by fitting
experimental data in calorimetric tests for polycarbonate, poly(methyl
methacrylate), polystyrene and poly(vinyl acetate). For all materials, fair
agreement is established between observations and results of numerical
simulation. For PVAc, the relaxation spectrum found by matching data in a
calorimetric test is successfully employed to predict experimental data in a
shear relaxation test.

</DOC>
<DOC>
<DOCNO> 150519 </DOCNO>
Conformality, Particle Phenomenology and the Cosmological Constant


  Conformality is the idea that at TeV scales enrichment of the standard model
particle spectrum leads to conformal invariance at a fixed point of the
renormalization group. Some aspects of conformality in particle phenomenology
and cosmology are discussed.

</DOC>
<DOC>
<DOCNO> 83337 </DOCNO>
Algorithms for Analysing Firewall and Router Access Lists


  Network firewalls and routers use a rule database to decide which packets
will be allowed from one network onto another. By filtering packets the
firewalls and routers can improve security and performance. However, as the
size of the rule list increases, it becomes difficult to maintain and validate
the rules, and lookup latency may increase significantly. Ordered binary
decision diagrams (BDDs) - a compact method of representing and manipulating
boolean expressions - are a potential method of representing the rules. This
paper presents a new algorithm for representing such lists as a BDD and then
shows how the resulting boolean expression can be used to analyse rule sets.

</DOC>
<DOC>
<DOCNO> 70073 </DOCNO>
Quark-Antiquark Bound States and the Breit Equation


  A non-covariant but approximately relativistic two-body wave equation (Breit
equation) describing the quantum mechanics of two fermions interacting with one
another through a potential containing scalar, pseudoscalar and vector parts is
presented. After expressing the sixteen component two-body wavefunction in
terms of a radial and an angular function by means of the multipole expansion,
the initial equation can be reduced into a set of sixteen radial equations
which, in turn, can be classified in accordance to the parity and the state of
the wavefunctions involved. The adequacy of the reduced equations in describing
real problems is discussed by applying the theory to QCD problems and the
calculation of the energies of bound states of quark-antiquark systems is
performed to order $\alpha^4$. We show that bound states of heavy quarks can be
described adequately by the Breit equation for a funnel interaction between the
particles

</DOC>
<DOC>
<DOCNO> 118968 </DOCNO>
Probing the Properties of Neutron Stars with Type-I X-Ray Bursts


  The increase in spin frequency as the burning atmospheres of TypeI X-ray
bursts cool provides a strong constraint on the radius of the underlying
neutron star. If the change in spin frequency is due to a change in the
thickness of the atmosphere, the radius of the star must exceed $3 G M/c^2$ for
any equation of state and approximately $3.5 G M/c^2$ for most physically
reasonable equations of state. This constraint arises because the direction of
the Coriolis force for radial motion reverses for $R < G / c^2 (M + I / R^2)$.
Furthermore, the marked change in the magnitude of the Coriolis force near
compact stars provides a straightforward explanation for why the frequency of
the quickly rotating bursters shifts by the same amount as the slow rotators;
they are slightly more massive, 1.6M$_\odot$ versus 1.4M$_\odot$. \

</DOC>
<DOC>
<DOCNO> 119567 </DOCNO>
A Catalogue of Galaxies in the HDF-South: Photometry and Structural


  We describe the construction of a catalogue of galaxies in the optical field
of the Hubble Deep Field South. The HDF-S observations produced WFPC2 images in
U, B, V, and I, the version 1 data have been made public on 23 November 1999.
The effective field of view is 4.38 arcmin$^2$, and the 5$\sigma$ limiting
magnitudes (in a FWHM aperture) are 28.87, 29.71, 30.19, 29.58 in the U, B, V
and I bands, respectively. We created a catalogue for each pass-band
(I$_{814}$, V$_{606}$, B$_{450}$, U$_{300}$), using simulations to account for
incompleteness and spurious sources contamination. Along with photometry in all
bands, we determined on the I$_{814}$-selected catalogue (I$_{814}<26$)
structural parameters, such as a metric apparent size, derived from the
petrosian radius, an asymmetry index, light concentration indexes and the mean
surface brightness within the petrosian radius.

</DOC>
<DOC>
<DOCNO> 152250 </DOCNO>
Quasi-Particles in Non-Commutative Field Theory


  After a short introduction to the UV/IR mixing in non-commutative field
theories we review the properties of scalar quasi-particles in non-commutative
supersymmetric gauge theories at finite temperature. In particular we discuss
the appearance of super-luminous wave propagation.

</DOC>
<DOC>
<DOCNO> 84777 </DOCNO>
The Geometry of the Frame Bundle over Spacetime


  One of the known mathematical descriptions of singularities in General
Relativity is the b-boundary, which is a way of attaching endpoints to
inextendible endless curves in a spacetime. The b-boundary of a manifold M with
connection is constructed by forming the Cauchy completion of the frame bundle
LM equipped with a certain Riemannian metric, the b-metric G. We study the
geometry of (LM,G) as a Riemannian manifold in the case when the connection is
the Levi-Civita connection of a Lorentzian metric g on M. In particular, we
give expressions for the curvature and discuss the isometries and the geodesics
of (LM,G) in relation to the geometry of (M,g).

</DOC>
<DOC>
<DOCNO> 9646 </DOCNO>
Color superconductivity in cold, dense quark matter


  We review what is different and what is similar in a color superconductor as
compared to an ordinary BCS superconductor. The parametric dependence of the
zero-temperature gap on the coupling constant differs in QCD from that in BCS
theory. On the other hand, the transition temperature to the superconducting
phase is related to the zero-temperature gap in the same way in QCD as in BCS
theory.

</DOC>
<DOC>
<DOCNO> 152570 </DOCNO>
Reduction of Coupling Parameters in Quantum Field Theories


  A concise survey is given of the general method of reduction in the number of
coupling parameters. Theories with several independent couplings are related to
a set of theories with a single coupling. The reduced theories may or may not
have particular symmetries. A few have asymptotic power series expansions,
others contain non-integer powers and/or logarithmic factors. An example is
given with two power series solutions, one with N = 2 Supersymmetry, and one
with no known symmetry. In a second example, the reduced Yukawa coupling of the
superpotential in a dual magnetic supersymmetric gauge theory is uniquely given
by the square of the magnetic gauge coupling with a known factor.

</DOC>
<DOC>
<DOCNO> 100572 </DOCNO>
Differential operators on equivariant vector bundles over symmetric


  Generalizing the algebra of motion-invariant differential operators on a
symmetric space we study invariant operators on equivariant vector bundles. We
show that the eigenequation is equivalent to the corresponding eigenequation
with respect to the larger algebra of all invariant operators. We compute the
possible eigencharacters and show that for invariant integral operators the
eigencharacter is given by the Abel transform. We show that sufficiently
regular operators are surjective, i.e. that equations of the form $Df=u$ are
solvable for all $u$.

</DOC>
<DOC>
<DOCNO> 80662 </DOCNO>
Lattice Gauge Fields and Discrete Noncommutative Yang-Mills Theory


  We present a lattice formulation of noncommutative Yang-Mills theory in
arbitrary even dimensionality. The UV/IR mixing characteristic of
noncommutative field theories is demonstrated at a completely nonperturbative
level. We prove a discrete Morita equivalence between ordinary Yang-Mills
theory with multi-valued gauge fields and noncommutative Yang-Mills theory with
periodic gauge fields. Using this equivalence, we show that generic
noncommutative gauge theories in the continuum can be regularized
nonperturbatively by means of {\it ordinary} lattice gauge theory with 't~Hooft
flux. In the case of irrational noncommutativity parameters, the rank of the
gauge group of the commutative lattice theory must be sent to infinity in the
continuum limit. As a special case, the construction includes the recent
description of noncommutative Yang-Mills theories using twisted large $N$
reduced models. We study the coupling of noncommutative gauge fields to matter
fields in the fundamental representation of the gauge group using the lattice
formalism. The large mass expansion is used to describe the physical meaning of
Wilson loops in noncommutative gauge theories. We also demonstrate Morita
equivalence in the presence of fundamental matter fields and use this property
to comment on the calculation of the beta-function in noncommutative quantum
electrodynamics.

</DOC>
<DOC>
<DOCNO> 10232 </DOCNO>
Brownian motion in a magnetic field


  We derive explicit forms of Markovian transition probability densities for
the velocity space, phase-space and the Smoluchowski configuration-space
Brownian motion of a charged particle in a constant magnetic field. By invoking
a hydrodynamical formalism for those stochastic processes, we quantify a
continual (net on the local average) heat transfer from the thermostat to
diffusing particles.

</DOC>
<DOC>
<DOCNO> 40243 </DOCNO>
Higgs Scalars in the Minimal Non-minimal Supersymmetric Standard Model


  We consider the simplest and most economic version among the proposed
non-minimal supersymmetric models, in which the $\mu$-parameter is promoted to
a singlet superfield, whose all self-couplings are absent from the
renormalizable superpotential. Such a particularly simple form of the
renormalizable superpotential may be enforced by discrete $R$-symmetries which
are extended to the gravity-induced non-renormalizable operators as well. We
show explicitly that within the supergravity-mediated supersymmetry-breaking
scenario, the potentially dangerous divergent tadpoles associated with the
presence of the gauge singlet first appear at loop levels higher than 5 and
therefore do not destabilize the gauge hierarchy. The model provides a natural
explanation for the origin of the $\mu$-term, without suffering from the
visible axion or the cosmological domain-wall problem. Focusing on the Higgs
sector of this minimal non-minimal supersymmetric standard model, we calculate
its effective Higgs potential by integrating out the dominant quantum effects
due to stop squarks. We then discuss the phenomenological implications of the
Higgs scalars predicted by the theory for the present and future high-energy
colliders. In particular, we find that our new minimal non-minimal
supersymmetric model can naturally accommodate a relatively light charged Higgs
boson, with a mass close to the present experimental lower bound.

</DOC>
<DOC>
<DOCNO> 120683 </DOCNO>
Multiplicity of massive stars


  We discuss the observed multiplicity of massive stars and implications on
theories of massive star formation. After a short summary of the literature on
massive star multiplicity, we focus on the O- and B-type stars in the Orion
Nebula Cluster, which constitute a homogenous sample of very young massive
stars. 13 of these stars have recently been the targets of a bispectrum speckle
interferometry survey for companions. Considering the visual and also the known
spectroscopic companions of these stars, the total number of companions is at
least 14. Extrapolation with correction for the unresolved systems suggests
that there are at least 1.5 and perhaps as much as 4 companions per primary
star on average. This number is clearly higher than the mean number of about
0.5 companions per primary star found for the low-mass stars in the general
field population and also in the Orion Nebula cluster. This suggests that a
different mechanism is at work in the formation of high-mass multiple systems
in the dense Orion Nebula cluster than for low-mass stars.

</DOC>
<DOC>
<DOCNO> 101182 </DOCNO>
Toward a Galoisian interpretation of homotopy theory


  Given any pointed CW complex (X,x), it is well known that the fondamental
group of X pointed at x is naturally isomorphic to the automorphism group of
the functor which associates to a locally constant sheaf on X its fibre at x.
The purpose of this work is to generalize this fact to higher homotopy. For
this we introduce the (infinite) category of locally constant stacks on X, and
we prove that the loop-space of endomorphisms of its fibre functor at x is
naturally equivalent to the loop space of X based at x.

</DOC>
<DOC>
<DOCNO> 10638 </DOCNO>
Quasiparticle relaxation dynamics in Hg-1223 studied by femtosecond


  Following recent progress in understanding the relaxation dynamics of
photoexcited carriers in materials exhibiting a small gap in the low-energy
excitation spectrum we have performed pump-probe measurements on near optimally
doped Hg-1223. We show that the behavior is very similar as in optimally-doped
YBCO, where the data can be interpreted with the coexisting presence of two
energy gaps: normal state T-independent pseudogap and a mean-field-like
collective gap, associated with intrinsic spatially inhomogeneous ground state.
An important difference between the two compounds is found in the low
temperature relaxation time, which in Hg-1223 is found to be strongly
temperature and photoexcitation intensity dependent.

</DOC>
<DOC>
<DOCNO> 11355 </DOCNO>
Josephson junction array type I-V characteristics of quench-condensed


  In this communication we report studies of d.c current-voltage (I-V)
characteristics of ultra thin films of Bi, quench condensed on single crystal
sapphire substrates at T = 15K. The hysteretic I-V characteristics are
explained using a resistively and capacitively shunted junction (RCSJ) model of
Josephson junction arrays. The Josephson coupling energy($E_J$) and the
charging energy($E_c$) are calculated for different thickness($d$) values. A
low resistance state is found in the low current regime below the critical
current, $I_c$. This resistance $R_0$ is found to have a minimum at a
particular thickness ($d_c$) value. Reflection High Energy Electron Diffraction
(RHEED) studies are done on these films. A distinct appearance of a diffuse
ring near $d_c$ is observed in the diffraction images, consistent with the
recent STM studies(Ekinci and Valles, PRL {\bf 82}(1999) 1518). These films
show an irreversible annealing when temperature is increased. The annealing
temperature ($T_a$) also has a maximum at the same thickness. Althoguh the
R$_s$ vs T of quench condensed Bi films suggest that the films are uniform, our
results indicate that even in thick films, the order parameter is not fully
developed over the complete area of the film. These results are discussed
qualitatively.

</DOC>
<DOC>
<DOCNO> 178550 </DOCNO>
Chiral properties of hadron correlators in nuclear matter


  The constraints imposed by chiral symmetry on hadron correlation functions in
nuclear medium are discussed. It is shown that these constraints imply a
certain structure for the in-medium hadron correlators and lead to the
cancelation of the order $\rho m_\pi$ term in the in-medium nucleon correlator.
We also consider the effect of mixing of the chiral partners correlation
functions arising from the interaction of nuclear pions with corresponding
interpolating currents. It reflects the phenomena of partial restoration of
chiral symmetry. The different scenarios of such restoration are briefly
discussed.

</DOC>
<DOC>
<DOCNO> 13367 </DOCNO>
Fast Monte Carlo algorithm for supercooled soft spheres


  We present a nonlocal Monte Carlo algorithm with particle swaps that greatly
accelerates thermalization of soft sphere binary mixtures in the glassy region.
Our first results show that thermalization of systems of hundreds of particles
is achievable, and find behavior compatible with a thermodynamic glass
transition.

</DOC>
<DOC>
<DOCNO> 71979 </DOCNO>
New insights concerning dimension-eight effects in weak decays


  Most past work on weak nonleptonic decays has mixed dimensional
regularization in the weak operator product expansion with some form of a
cutoff regularization in the evaluation of the matrix elements. Even with the
usual technique of matching the two schemes, this combination misses physics at
short distance which can be described by dimension eight (and higher dimension)
operators. I describe some recent work with V. Cirigliano and E. Golowich which
clarifies these effects and provides a numerical estimate suggesting that they
are important.

</DOC>
<DOC>
<DOCNO> 71802 </DOCNO>
One-loop Singular Behaviour of QCD and SUSY QCD Amplitudes with Massive


  We discuss the structure of infrared and ultraviolet singularities in
on-shell QCD and supersymmetric QCD amplitudes at one-loop order. Previous
results, valid for massless partons, are extended to the case of massive
partons. Using dimensional regularization, we present a general factorization
formula that controls both the singular epsilon-poles and the logarithmic
contributions that become singular for vanishing masses. We introduce
generalized Altarelli--Parisi splitting functions and discuss their relations
with the singular terms in the amplitudes. The dependence on the regularization
scheme is also considered.

</DOC>
<DOC>
<DOCNO> 151541 </DOCNO>
Non Trivial Extension of the (1+2)-Poincar\'e Algebra and Conformal


  Using recent results on string on $AdS_{3}\times N^d$, where N is a
d-dimensional compact manifold, we re-examine the derivation of the non trivial
extension of the (1+2) dimensional-Poincar\'e algebra obtained by Rausch de
Traubenberg and Slupinsky, refs [1] and [29]. We show by explicit computation
that this new extension is a special kind of fractional supersymmetric algebra
which may be derived from the deformation of the conformal structure living on
the boundary of $AdS_3$. The two so(1,2) Lorentz modules of spin $\pm{1\over
k}$ used in building of the generalisation of the (1+2) Poincar\'e algebra are
re-interpreted in our analysis as highest weight representations of the left
and right Virasoro symmetries on the boundary of $AdS_3$. We also complete
known results on 2d-fractional supersymmetry by using spectral flow of affine
Kac-Moody and superconformal symmetries. Finally we make preliminary comments
on the trick of introducing Fth-roots of g-modules to generalise the so(1,2)
result to higher rank lie algebras g.

</DOC>
<DOC>
<DOCNO> 120585 </DOCNO>
Effect of the Environment on the Fundamental Plane of Elliptical


  We present an analysis of interacting E/S0 galaxies location on the
Fundamental Plane. Using the NEMO package, we performed N-body simulations of
close encounters and mergers between two spherical galaxies. We followed how
structural and dynamical parameters (central density, half-mass radius and
velocity dispersion)of galaxies are changed during the encounter. We analysed
the dependence of these changes on initial mass concentration and presence of
dark halo. The results of our simulations are used to discuss the Fundamental
Plane for interacting early-type galaxies.

</DOC>
<DOC>
<DOCNO> 11446 </DOCNO>
Measurement of persistence in 1D diffusion


  Using a novel NMR scheme we observed persistence in 1-D gas diffusion.
Analytical approximations and numerical simulations have indicated that for an
initially random array of spins undergoing diffusion, the probability p(t) that
the average spin magnetization in a given region has not changed sign (i.e.,
``persists'') up to time t follows a power law t^{-\theta}, where \theta\
depends on the dimensionality of the system. Using laser-polarized ^{129}Xe
gas, we prepared an initial ``quasirandom'' 1D array of spin magnetization and
then monitored the ensemble's evolution due to diffusion using real-time NMR
imaging. Our measurements are consistent with analytical and numerical
predictions of \theta \approx 0.12.

</DOC>
<DOC>
<DOCNO> 85103 </DOCNO>
Generally covariant model of a scalar field with high frequency


  Short distance structure of spacetime may show up in the form of high
freqency dispersion. Although such dispersion is not locally Lorentz invariant,
we show in a scalar field model how it can nevertheless be incorporated into a
generally covariant metric theory of gravity provided the locally preferred
frame is dynamical. We evaluate the resulting energy-momentum tensor and
compute its expectation value for a quantum field in a thermal state. The
equation of state differs at high temperatures from the usual one, but not by
enough to impact the problems of a hot big bang cosmology. We show that a
superluminal dispersion relation can solve the horizon problem via superluminal
equilibration, however it cannot do so while remaining outside the Planck
regime unless the dispersion relation is artificially chosen to have a rather
steep dependence on wavevector.

</DOC>
<DOC>
<DOCNO> 151979 </DOCNO>
Summation and renormalization of bubble graphs to all orders


  We introduce the 2PPI expansion which sums the bubble graphs to all orders.
We show that this expansion can be renormalised with the usual counterterms in
a mass independent scheme. We discuss its application to the O(N) linear sigma
model.

</DOC>
<DOC>
<DOCNO> 101533 </DOCNO>
Local Analysis of Nonlinear RMS Envelope Dynamics


  We present applications of variational -- wavelet approach to nonlinear
(rational) rms envelope dynamics. We have the solution as a multiresolution
(multiscales) expansion in the base of compactly supported wavelet basis.

</DOC>
<DOC>
<DOCNO> 121967 </DOCNO>
Kinematics of 1200 km/s Jets in He 3-1475


  Spectroscopic observations of a proto-planetary nebula He 3-1475 with the
Space Telescope Imaging Spectrograph (STIS) reveal the kinematics of its high
(1200 km/s) velocity jets. The jets are formed at a large (0.15 pc) distance
from its central star by collimation of an asymmetric stellar wind in a pair of
conical shocks seen in Wide Field Planetary Camera (WFPC2) images. The jets
consist of several pairs of knots symmetrically distributed with respect to the
central star, with most knots exhibiting a head-tail morphology. Large (up to
650 km/s) radial velocity gradients are seen within the knots on subarcsec
scales, with velocities decreasing from the knot heads toward their trailing
tails. These large velocity gradients are a sign of efficient deceleration of
jets by a much slower bipolar outflow. The inclination angle of the bipolar
outflow is equal to 40 degrees, based on Doppler shifts of the scattered
stellar Halpha line. Its velocity is equal to 140 km/s at a distance of 0.23 pc
from the star, and increases monotonically with the radial distance from the
star. A comparison of new WFPC2 [N II] 6584 images with older WFPC2 images
reveals expansion of the jets. The measured jet proper motions in combination
with their radial velocities imply that He 3-1475 is a Galactic Bulge star at a
distance of 8 kpc, located 800 pc above the Galactic plane. Its very high
luminosity (25,000 solar luminosities) implies that He 3-1475 must be
significantly more massive than a typical AGB star within the Galactic Bulge,
perhaps because of a past mass transfer and/or a merger event in an interacting
binary system.

</DOC>
<DOC>
<DOCNO> 100924 </DOCNO>
Motivic measures


  A survey of work on motivic integration.

</DOC>
<DOC>
<DOCNO> 151274 </DOCNO>
Effective Action - A Convergent Series - of QED


  The one-loop effective action of QED obtained by Euler and Heisenberg and by
Schwinger has been expressed by an asymptotic perturbative series which is
divergent. In this letter we present a non-perturbative but convergent series
of the effective action. With the convergent series we establish the existence
of the manifest electric-magnetic duality in the one loop effective action of
QED.

</DOC>
<DOC>
<DOCNO> 100750 </DOCNO>
Part of the D - dimensional Spiked harmonic oscillator spectra


  The pseudoperturbative shifted - l expansion technique PSLET [5,20] is
generalized for states with arbitrary number of nodal zeros. Interdimensional
degeneracies, emerging from the isomorphism between angular momentum and
dimensionality of the central force Schrodinger equation, are used to construct
part of the D - dimensional spiked harmonic oscillator bound - states. PSLET
results are found to compare excellenly with those from direct numerical
integration and generalized variational methods [1,2].

</DOC>
<DOC>
<DOCNO> 9953 </DOCNO>
The direct Cu NQR Study of the Stripe Phase in the Lanthanum Cuprates


  Using Cu NQR in Eu-doped La_(2-x)Sr_xCuO_4 we find the evidence of the pinned
stripe phase at 1.3K for 0.08<x<0.18. The pinned fraction increases by one
order of magnitude near hole doping x=1/8. The NQR lineshape reveals three
inequivalent Cu positions. A dramatic change of the NQR signal for x > 0.18
correlating with the onset of bulk superconductivity corresponds to the
depinning of the stripe phase.

</DOC>
<DOC>
<DOCNO> 9864 </DOCNO>
On the electron scattering and dephasing by the nuclear spins


  We show that scattering of the conduction electrons by nuclear spins via the
hyperfine interaction may lead the upper limit on the mean free path in clean
metals. Nuclear spins with s >1/2 may cause a strong dephasing in dirty limit
due to the quadrupole coupling to the random potential fluctuations caused by
static impurities and lattice imperfections.

</DOC>
<DOC>
<DOCNO> 119739 </DOCNO>
[OII] Emission, Eigenvector 1 and Orientation in Radio-quiet Quasars


  We present supportive evidence that the Boroson and Green eigenvector 1 is
not driven by source orientation. Until recently it was generally accepted that
eigenvector 1 does not depend on orientation as it strongly correlates with
[OIII]5007 emission, thought to be an isotropic property. However, recent
studies of radio-loud AGN have questioned the isotropy of [OIII] emission and
concluded that [OII]3727 emission is isotropic. In this paper we investigate
the relation between eigenvector 1 and [OII] emission in radio-quiet BQS
(Bright Quasar Survey) quasars, and readdress the issue of orientation as the
driver of eigenvector 1. We find significant correlations between eigenvector 1
and orientation independent [OII] emission, which implies that orientation does
not drive eigenvector 1. The luminosities and equivalent widths of [OIII] and
[OII] correlate with one another, and the range in luminosities and equivalent
widths is similar. This suggests that the radio-quiet BQS quasars are largely
free of orientation dependent dust effects and ionization dependent effects in
the narrow-line region. We also conclude that neither the [OIII] emission nor
the [OII]/[OIII] ratio are dependent on orientation in our radio-quiet BQS
quasar sample, contrary to recent results found for radio-loud quasars.

</DOC>
<DOC>
<DOCNO> 71726 </DOCNO>
Neutrino Unification


  Present neutrino data are consistent with neutrino masses arising from a
common seed at some ``neutrino unification'' scale $M_X$. Such a simple
theoretical ansatz naturally leads to quasi-degenerate neutrinos that could lie
in the electron-volt range with neutrino mass splittings induced by
renormalization effects associated with supersymmetric thresholds. In such a
scheme the leptonic analogue of the Cabibbo angle $\theta_{\odot}$ describing
solar neutrino oscillations is nearly maximal. Its exact value is correlated
with the smallness of $\theta_{reactor}$. These features agree both with latest
data on the solar neutrino spectra and with the reactor neutrino data. The two
leading mass-eigenstate neutrinos present in \ne form a pseudo-Dirac neutrino,
avoiding conflict with neutrinoless double beta decay.

</DOC>
<DOC>
<DOCNO> 122826 </DOCNO>
Spectroscopic investigation of old planetaries V. Distance scales


  We use the results of our recent NLTE model atmosphere analysis of central
stars of old planetary nebulae (PN) to calculate distances. We perform a
comparison with three other methods (trigonometric parallaxes, interstellar NaD
lines, and Shklovsky distances) and discuss the problem of the PNe distance
scale. The result of the comparison of our spectroscopic distances with the
trigonometric distances is that the spectroscopic distances are 55% larger.
Since using trigonometric parallaxes with large relative measurement errors can
introduce systematic errors, we carried out a Monte Carlo simulation of the
biases introduced by selection effects and measurement errors. It turns out
that a difference between both distance scales of the observed size is expected
for the present day data if the underlying distance scales are identical. Thus
our finding is essentially a confirmation of the spectroscopic distance scale!
Good agreement is found between the spectroscopic distances and distances
derived from the interstellar NaD lines.
  All three independent methods of distance measurement indicate that the
widely used "statistical" distance scales of the Shklovsky type are too short
for old PNe. A correlation with nebular radii exists. The most likely
explanation is an underestimate of the nebula masses for large PN. Implications
for the nebula masses are discussed. Estimates of the PNe space density and
birthrate, which are based on Shklovsky type distances, therefore give too
large values.

</DOC>
<DOC>
<DOCNO> 13679 </DOCNO>
Generating Functional Analysis of the Dynamics of the Batch Minority


  We study the dynamics of the batch minority game, with random external
information, using generating functional techniques a la De Dominicis. The
relevant control parameter in this model is the ratio $\alpha=p/N$ of the
number $p$ of possible values for the external information over the number $N$
of trading agents. In the limit $N\to\infty$ we calculate the location
$\alpha_c$ of the phase transition (signaling the onset of anomalous response),
and solve the statics for $\alpha>\alpha_c$ exactly. The temporal correlations
in global market fluctuations turn out not to decay to zero for infinitely
widely separated times. For $\alpha<\alpha_c$ the stationary state is shown to
be non-unique. For $\alpha\to 0$ we analyse our equations in leading order in
$\alpha$, and find asymptotic solutions with diverging volatility
$\sigma=\order(\alpha^{-{1/2}})$ (as regularly observed in simulations), but
also asymptotic solutions with vanishing volatility
$\sigma=\order(\alpha^{{1/2}})$. The former, however, are shown to emerge only
if the agents' initial strategy valuations are below a specific critical value.

</DOC>
<DOC>
<DOCNO> 8852 </DOCNO>
Superconductivity at Very Hygh Temperatures - Hyperconductivity


  The mechanism of superconductivity caused by the electron-vibrational centres
and their inherent oscillations in crystals and solid-state structures near
room temperature and at higher temperatures - hyperconductivity is discussed
and actualized. The experimental data about hiperconductivity in some materials
are presented. Hyperconductivity arises and exists from normal-superconducting
transition temperature Tc to 800K and probably up to melting of material
(probably up to temperature of crystal melting and is higher). Tc in various
materials varies from hundred up to several hundreds degrees on Kelvin scale
depending on size of average nuclear number of a material.

</DOC>
<DOC>
<DOCNO> 84579 </DOCNO>
Isotropization of two-component fluids


  We consider the problem of late-time isotropization in spatially homogeneous
but anisotropic cosmological models when the source of the gravitational field
consists of two non-interacting perfect fluids -- one tilted and one
non-tilted. In particular, we study irrotational Bianchi type V models. By
introducing appropriate dimensionless variables, a full global understanding of
the state space of the gravitational field equations becomes possible. The
issue of isotropization can then be addressed in a simple fashion. We also
discuss implications for the cosmic ``no-hair'' theorem for Bianchi models when
part of the source is a tilted fluid.

</DOC>
<DOC>
<DOCNO> 67811 </DOCNO>
A Hamiltonian model for multiple production in hadron-hadron collisions


  A Hamiltonian eikonal model for the multiple production in high energy hadron
hadron collisions is presented and worked out in the aim of providing a simple
frame for many different observables of these processes. The Hamiltonian
formulation ensures that it has the unitarity built in by construction and the
eikonal approximation makes easier the discussion of the possible spacial
inhomogeneities of the hadrons. The experimental data which are examined are
the inelastic cross section and the single and double inclusive cross sections.

</DOC>
<DOC>
<DOCNO> 69100 </DOCNO>
Exhaustive Study of Cosmic Microwave Background Anisotropies in


  Recent high precision measurements of the CMB anisotropies performed by the
BOOMERanG and MAXIMA-1 experiments provide an unmatched set of data allowing to
probe different cosmological models. Among these scenarios, motivated by the
recent measurements of the luminosity distance versus redshift relation for
type Ia supernovae, is the quintessence hypothesis. It consists in assuming
that the acceleration of the Universe is due to a scalar field whose final
evolution is insensitive to the initial conditions. Within this framework we
investigate the cosmological perturbations for two well-motivated potentials:
the Ratra-Peebles and the SUGRA tracking potentials. We show that the solutions
of the perturbed equations possess an attractor and that, as a consequence, the
insensitivity to the initial conditions is preserved at the perturbed level.
Then, we study the predictions of these two models for structure formation and
CMB anisotropies and investigate the general features of the multipole moments
in the presence of quintessence. We also compare the CMB multipoles calculated
with the help of a full Boltzmann code with the BOOMERanG and MAXIMA-1 data. We
pay special attention to the location of the second peak and demonstrate that
it significantly differs from the location obtained in the cosmological
constant case. Finally, we argue that the SUGRA potential is compatible with
all the recent data with a standard values of the cosmological parameters. In
particular, it fits the MAXIMA-1 data better than a cosmological constant or
the Ratra-Peebles potential.

</DOC>
<DOC>
<DOCNO> 11274 </DOCNO>
Tutorial on quasi-sparse eigenvector diagonalization


  We review several topics related to the diagonalization of quantum field
Hamiltonians using the quasi-sparse eigenvector (QSE) method.

</DOC>
<DOC>
<DOCNO> 102119 </DOCNO>
Examples of Amenable Kac system


  By giving an interesting characterisation of amenable multiplicative
unitaries in term of one dimensional representations, we show in a simple way
that bicrossproducts of amenable locally compact groups is both amenable and
coamenable.

</DOC>
<DOC>
<DOCNO> 101999 </DOCNO>
p^q-Catalan Numbers and Squarefree Binomial Coefficients


  In this paper we consider the generalized Catalan numbers F(s,n)=
1/((s-1)n+1) binom{sn}{n}. We find all $n$ such that for $p$ prime, p^q divides
F(p^q,n), q>=1. As a byproduct we settle a question of Hough and the late
Simion on the divisibility of the 4-Catalan numbers. We also prove that
\binom{p^qn+1}{n}, p^q<=99999, is squarefree for n sufficiently large
(explicit), and with the help of the generalized Catalan numbers we find the
set of possible exceptions. As consequences, we obtain that binom{4n+1}{n},
binom{9n+1}{n} are squarefree for n> 2^{1518}, respectively n>3^{956}, with at
most 2^{18.2}, respectively 3^{15.3} possible exceptions.

</DOC>
<DOC>
<DOCNO> 117880 </DOCNO>
Resolving the extragalactic hard X-ray background


  The origin of the hard (2-10 keV) X-ray background has remained mysterious
for over 35 years. Most of the soft (0.5-2 keV) X-ray background has been
resolved into discrete sources, which are primarily quasars; however, these
sources do not have the flat spectral shape required to match the X-ray
background spectrum. Here we report the results of an X-ray survey 30 times
more sensitive than previous studies in the hard band and four times more
sensitive in the soft band. The sources detected in our survey account for at
least 75 per cent of the hard X-ray background. The mean X-ray spectrum of
these sources is in good agreement with that of the background. The X-ray
emission from the majority of the detected sources is unambiguously associated
with either the nuclei of otherwise normal bright galaxies or optically faint
sources, which could either be active nuclei of dust enshrouded galaxies or the
first quasars at very high redshifts.

</DOC>
<DOC>
<DOCNO> 178991 </DOCNO>
Parity-Violating Pion-Nucleon Coupling h_{\pi NN}^{(1)} from \pi^+


  We study the possibility of measuring parity-violating pion-nucleon coupling
h_{\pi NN}^{(1)} from \pi^+ electroproton production in the threshold region.
We calculate the electron-helicity asymmetry in terms of h_{\pi NN}^{(1)} and
the Z-boson exchange between the electron and proton in leading-order
heavy-baryon chiral perturbation theory. From the result, we demonstrate that
the coupling can be determined to an accuracy of about 2 10^{-7} in an
experiment with incident electron energy 250 MeV, luminosity 10^{38} sec^{-1}
cm^{-2}, and a running time of 10^7 sec.

</DOC>
<DOC>
<DOCNO> 102555 </DOCNO>
Hopf Algebra Equivariant Cyclic Homology and Cyclic Homology of Crossed


  We introduce the cylindrical module $A \natural \mathcal{H}$, where
$\mathcal{H}$ is a Hopf algebra and $A$ is a Hopf module algebra over
$\mathcal{H}$. We show that there exists an isomorphism between
$\mathsf{C}_{\bullet}(A^{op} \rtimes \mathcal{H}^{cop})$ the cyclic module of
the crossed product algebra $A^{op} \rtimes \mathcal{H}^{cop} $, and $\Delta(A
\natural \mathcal{H}) $, the cyclic module related to the diagonal of $A
\natural \mathcal{H}$. If $S$, the antipode of $\mathcal{H}$, is invertible it
follows that $\mathsf{C}_{\bullet}(A \rtimes \mathcal{H}) \simeq \Delta(A^{op}
\natural \mathcal{H}^{cop})$. When $S$ is invertible, we approximate
$HC_{\bullet}(A \rtimes \mathcal{H})$ by a spectral sequence and give an
interpretation of $ \mathsf{E}^0, \mathsf{E}^1$ and $\mathsf{E}^2 $ terms of
this spectral sequence.

</DOC>
<DOC>
<DOCNO> 84963 </DOCNO>
Satellite non-gravitational orbital perturbations and the detection of


  The general relativistic gravitomagnetic clock effect consists in the fact
that two massive test bodies orbiting a central spinning mass in its equatorial
plane along two identical circular trajectories, but in opposite directions,
take different times in describing a full revolution with respect to an
asymptotically inertial observer. In the field of the Earth such time shift
amounts to 10^{-7} s. Detecting it by means of a space based mission with
artificial satellites is a very demanding task because there are severe
constraints on the precision with which the radial and azimuthal positions of a
satellite must be known: delta r= 10^{-2} cm and delta phi= 10^{-2}
milliarcseconds per revolution. In this paper we assess if the systematic
errors induced by various non-gravitational perturbations allow to meet such
stringent requirements. A couple of identical, passive laser-ranged satellites
of LAGEOS type with their spins aligned with the Earth's one is considered. It
turns out that all the non vanishing non-gravitational perturbations induce
systematic errors in r and phi within the required constraints for a reasonable
assumption of the mismodeling in some satellite's and Earth's parameters and/or
by using dense satellites with small area-to-mass ratio. However, the error in
the Earth's GM is by far the largest source of uncertainty in the azimuthal
location which is affected at a level of 1.2 milliarcseconds per revolution.

</DOC>
<DOC>
<DOCNO> 122530 </DOCNO>
Evolving Stellar Background Radiation and Gamma-Ray Optical Depth


  We present a semi-empirical model for the evolving far-infrared to
ultraviolet diffuse background produced by stars in galaxies. The model is
designed to reproduce the results of deep galaxy surveys, and therefore may be
considered as a cosmology-independent lower limit to the extragalactic
background light. Using this model and recent HEGRA data, we infer the
intrinsic spectrum at multi-TeV gamma-ray energies for Mkn501 and find that it
is consistent with a power law of spectral index 2.49+-0.04. In turn, this
finding renders it rather unlikely that the present-day infrared background has
an intensity as high as claimed by Finkbeiner et al. (2000). Future 10GeV to
TeV observations could be used to either constrain the ultraviolet-to-infrared
background model at high redshifts or cosmological parameters.

</DOC>
<DOC>
<DOCNO> 83446 </DOCNO>
Non-intrusive on-the-fly data race detection using execution replay


  This paper presents a practical solution for detecting data races in parallel
programs. The solution consists of a combination of execution replay (RecPlay)
with automatic on-the-fly data race detection. This combination enables us to
perform the data race detection on an unaltered execution (almost no probe
effect). Furthermore, the usage of multilevel bitmaps and snooped matrix clocks
limits the amount of memory used. As the record phase of RecPlay is highly
efficient, there is no need to switch it off, hereby eliminating the
possibility of Heisenbugs because tracing can be left on all the time.

</DOC>
<DOC>
<DOCNO> 68727 </DOCNO>
RunDec: a Mathematica package for running and decoupling of the strong


  In this paper the formulae are collected which are needed for the computation
of the strong coupling constant and quark masses at different energy scales and
for different number of active flavours. All equations contain the
state-of-the-art QCD corrections up to three- and sometimes even four-loop
order. For the practical implementation {\tt Mathematica} is used and a package
containing useful procedures is provided.

</DOC>
<DOC>
<DOCNO> 152426 </DOCNO>
Multiple "parallel" D-branes seen as leaves of foliations and Duminy's


  We try to give a qualitative description of the Godbillon-Vey class and its
relation on the one hand to the holonomy and on the other hand to the
topological entropy of a foliation, using a remarkable theorem proved recently
by G. Duminy (which still remains unpublished), relating these three notions in
the case of codim-1 foliations. Moreover we shall investigate its possible
consequences on string theory. In particular we shall present a conceptual
argument according to which the curvature of the B-field (rank two
antisymmetric tensor) of open strings might be related to the Godbillon-Vey
class using a suitable generalisation of ``Non-Abelian Geometry'' which has
just appeared in physics literature. Our starting point again is the
Connes-Douglas-Schwarz article on compactifications of matrix models to
noncommutative tori.

</DOC>
<DOC>
<DOCNO> 117230 </DOCNO>
Pressure determinations for incompressible fluids and magnetofluids


  Certain unresolved ambiguities surround pressure determinations for
incompressible flows, both Navier-Stokes and magnetohydrodynamic. For
uniform-density fluids with standard Newtonian viscous terms, taking the
divergence of the equation of motion leaves a Poisson equation for the pressure
to be solved. But Poisson equations require boundary conditions. For the case
of rectangular periodic boundary conditions, pressures determined in this way
are unambiguous. But in the presence of "no-slip" rigid walls, the equation of
motion can be used to infer both Dirichlet and Neumann boundary conditions on
the pressure P, and thus amounts to an over-determination. This has
occasionally been recognized as a problem, and numerical treatments of
wall-bounded shear flows usually have built in some relatively ad hoc dynamical
recipe for dealing with it, often one which appears to "work" satisfactorily.
Here we consider a class of solenoidal velocity fields which vanish at no-slip
walls, have all spatial derivatives, but are simple enough that explicit
analytical solutions for P can be given. Satisfying the two boundary conditions
separately gives two pressures, a "Neumann pressure" and a "Dirichlet pressure"
which differ non-trivially at the initial instant, even before any dynamics are
implemented. We compare the two pressures, and find that in particular, they
lead to different volume forces near the walls. This suggests a reconsideration
of no-slip boundary conditions, in which the vanishing of the tangential
velocity at a no-slip wall is replaced by a local wall-friction term in the
equation of motion.

</DOC>
<DOC>
<DOCNO> 39972 </DOCNO>
Dynamical Symmetry Breaking in the Sea of the Nucleon


  We derive the non-analytic chiral behavior of the flavor asymmetry dbar -
ubar. Such behavior is a unique characteristic of Goldstone boson loops in
chiral theories, including QCD, and establishes the unambiguous role played by
the Goldstone boson cloud in the sea of the proton. Generalizing the results to
the SU(3) sector, we show that strange chiral loops require that the s - sbar
distribution be non-zero.

</DOC>
<DOC>
<DOCNO> 122922 </DOCNO>
Optical Surface Photometry of a Sample of Disk Galaxies. II Structural


  This work presents the structural decomposition of a sample of 11 disk
galaxies, which span a range of different morphological types.
  The U, B, V, R, and I photometric information given in Paper I (color and
color-index images and luminosity, ellipticity, and position-angle profiles)
has been used to decide what types of components form the galaxies before
carrying out the decomposition. We find and model such components as bulges,
disks, bars, lenses and rings.

</DOC>
<DOC>
<DOCNO> 84855 </DOCNO>
A new holographic entropy bound from quantum geometry


  A new entropy bound, tighter than the standard holographic bound due to
Bekenstein, is derived for spacetimes with non-rotating isolated horizons, from
the quantum geometry approach in which the horizon is described by the boundary
degrees of freedom of a three dimensional Chern Simons theory.

</DOC>
<DOC>
<DOCNO> 151579 </DOCNO>
Quantum mechanics with non-unitary symmetries


  This article shows that one can consistently incorporate nonunitary
representations of at least one group into the ``ordinary'' nonrelativistic
quantum mechanics. This group turns out to be Lorentz group thus giving us an
alternative approach to QFT for combining the quantum mechanics and special
theory of relativity which keeps the concept of wave function (belonging to
some representation of Lorentz group) through the whole theory. Scalar product
has been redefined to take into the account the nonunitarity of representations
of Lorentz group. Understanding parity symmetry turns out to be the key
ingredient throughout the process. Instead of trying to guess an equation or a
set of equations for some wave functions or fields (or equivalently trying to
guess a Lagrangian for the same), one derives them based only on the
superposition principle and properties of wave functions under Lorentz
transformations and parity. The resulting model has striking similarities with
the standard quantum field theory and yet has no negative energy states, no
zitterbewegung effects, symmetric energy momentum tensor and angular momentum
density tensor for \emph{all} representations of Lorentz group (unifying the
theoretical description of all particles), as well as clear physical
interpretation. It also offers a possible interpretation why particles and
antiparticles have opposite quantum numbers.

</DOC>
<DOC>
<DOCNO> 8093 </DOCNO>
Influence of measurement on the life-time and the line-width of unstable


  We investigate the quantum Zeno effect in the case of electron tunneling out
of a quantum dot in the presence of continuous monitoring by a detector. It is
shown that the Schr\"odinger equation for the whole system can be reduced to
Bloch-type rate equations describing the combined time-development of the
detector and the measured system. Using these equations we find that continuous
measurement of the unstable system does not affect its exponential decay to a
reservoir with a constant density of states. The width of the energy
distribution of the tunneling electron, however, is not equal to the inverse
life-time -- it increases due to the decoherence generated by the detector. We
extend the analysis to the case of a reservoir described by an energy dependent
density of states, and we show that continuous measurement of such quantum
systems affects both the exponential decay rate and the energy distribution.
The decay does not always slow down, but might be accelerated. The energy
distribution of the tunneling electron may reveal the lines invisible before
the measurement.

</DOC>
<DOC>
<DOCNO> 8798 </DOCNO>
Dislocation Kinks in Copper: Widths, Barriers, Effective Masses, and


  We calculate the widths, migration barriers, effective masses, and quantum
tunneling rates of kinks and jogs in extended screw dislocations in copper,
using an effective medium theory interatomic potential. The energy barriers and
effective masses for moving a unit jog one lattice constant are close to
typical atomic energies and masses: tunneling will be rare. The energy barriers
and effective masses for the motion of kinks are unexpectedly small due to the
spreading of the kinks over a large number of atoms. The effective masses of
the kinks are so small that quantum fluctuations will be important. We discuss
implications for quantum creep, kink--based tunneling centers, and Kondo
resonances.

</DOC>
<DOC>
<DOCNO> 40263 </DOCNO>
Rare radiative B decay to the orbitally excited K_2^*(1430) meson


  The exclusive rare radiative B meson decay to the orbitally excited tensor
K_2^*(1430) meson is investigated in the framework of the relativistic quark
model based on the quasipotential approach in quantum field theory. The
calculated branching ratio BR(B --> K_2^*(1430)\gamma)=(1.7\pm 0.6)\times
10^{-5} as well as the ratio BR(B --> K_2^*(1430)\gamma)/BR(B -->
K^*(892)\gamma)=0.38\pm 0.08 is found in a good agreement with recent
experimental data from CLEO.

</DOC>
<DOC>
<DOCNO> 122992 </DOCNO>
Astronomical x-ray polarimetry based on photoelectric effect with


  The polarisation of x-ray photons can be determined by measuring the
direction of emission of a K-shell photoelectron. Effective exploitation of
this effect below 10 keV would allow development of a highly sensitive x-ray
polarimeter dedicated in particular to x-ray astronomy observations. Only with
the advent of finely segmented gas detectors was it possible to detect
polarisation sensitivity based on the photoelectric effect in this energy
range. Simulation and measurements at 5.4 and 8.04 keV with a microgap gas
counter, using both a polarised and an unpolarised x-ray source, showed that
the photoelectron track in a neon-based gas mixture retains the memory of the
polarisation of the incoming photons. Possible experiments aimed at
galactic/extragalactic sources and solar flares are considered and their
sensitivity to these sources is calculated.

</DOC>
<DOC>
<DOCNO> 122200 </DOCNO>
Supernova and Cosmology


  These lecture notes intend to form a short pedagogical introduction to the
use of typical type Ia-Supernovae (hereafter SNIa) as standard candles to
determine the energy density of the universe. Problems of principle for taking
SNIa as cosmological probes are pointed out, and new attempts at solving them
are indicated including the empirical width-luminosity relation and its
possible explanations. Finally, the observations of SNIa at high redshift
carried out by two major teams are briefly reviewed and their interpretation as
evidence for an accelerating universe is also rapidly discussed.

</DOC>
<DOC>
<DOCNO> 8075 </DOCNO>
Antiferromagnetic Order of the Ru and Gd in Superconducting RuSr2GdCu2O8


  Neutron diffraction has been used to study the magnetic order in
RuSr{2}GdCu2O8. The Ru moments order antiferromagnetically at T{N}=136(2)K,
coincident with the previously reported onset of ferromagnetism. Neighboring
spins are antiparallel in all three directions, with a low T moment of 1.18(6)
mu {B} along the c-axis. Our measurements put an upper limit of ~0.1 mu{B} to
any net zero-field moment, with fields exceeding ~0.4T needed to induce a
measurable magnetization. The Gd ions order independently at T{N}=2.50(2)K with
the same spin configuration. PACS numbers: 74.72.Jt, 75.25.+z, 74.25.Ha,
75.30.Kz

</DOC>
<DOC>
<DOCNO> 121262 </DOCNO>
Astrometric demands of fibre-input spectrographs for wide-field quasar


  A potential problem with using wide-field multi-object spectrographs for
quasar redshift surveys is the introduction of position-dependent selection
effects into the survey catalogue because of variations in the observed
signal-to-noise ratio (SNR) across the survey area. A function relating signal
losses in instruments using optical fibre input to the fibre-to-image position
error, the fibre diameter and the seeing conditions is given and plotted for a
range of typical values of fibre sizes and seeing found in current instruments.

</DOC>
<DOC>
<DOCNO> 119336 </DOCNO>
Formation of cuspy density profiles - a generic feature of collisionless


  Using the formalism of the spherical infall model the structure of collapsed
and virialized dark halos is calculated for a variety of scale-free initial
conditions. In spite of the scale-free cosmological nature of the problem, the
collapse of individual objects is not self-similar. Unlike most of previous
calculations the dynamics used here relies only on adiabatic invariants and not
on self-similarity. The paper focuses on the structure of the innermost part of
the collapsed halos and addresses the problem of central density cusps. The
slopes of density profiles at 1% of virial radius are calculated for a variety
of cosmological models and are found to vary with the mass of the halos and
power spectrum of the initial conditions. The inner slopes range between r^-2.3
and r^-2 with the limiting case of r^-2 reached for the largest masses. The
steep cusps found here correspond to the limiting case where all particles move
on radial orbits. The introduction of angular momentum will make the density
profile shallower. We expect this to resolve the discrepancy found between the
calculated profiles and the ones found in high resolution N-body simulations,
where the exponent ranges from -0.5 to -1.5. The robust prediction here is that
collisionless gravitational collapse in an expanding universe is expected to
form density cups and not halos with a core structure.

</DOC>
<DOC>
<DOCNO> 83418 </DOCNO>
Internet Packet Filter Management and Rectangle Geometry


  We consider rule sets for internet packet routing and filtering, where each
rule consists of a range of source addresses, a range of destination addresses,
a priority, and an action. A given packet should be handled by the action from
the maximum priority rule that matches its source and destination. We describe
new data structures for quickly finding the rule matching an incoming packet,
in near-linear space, and a new algorithm for determining whether a rule set
contains any conflicts, in time O(n^{3/2}).

</DOC>
<DOC>
<DOCNO> 118700 </DOCNO>
An H alpha Survey of 8 Abell Clusters: the dependence of tidally-induced


  We have undertaken a survey of H alpha emission in a substantially complete
sample of CGCG galaxies of types Sa and later within 1.5 Abell radii of the
centres of 8 low-redshift Abell clusters. Some 320 galaxies were surveyed, of
which 116 were detected in emission (39% of spirals, 75% of peculiars).
Detected emission was classified as `compact' or `diffuse'. From an analysis of
the full survey sample, we reconfirm our previous identification of compact and
diffuse emission with circumnuclear starburst and disk emission respectively.
The circumnuclear emission is associated either with the presence of a bar, or
with a disturbed galaxy morphology indicative of on-going tidal interactions.
The frequency of such tidally-induced (circumnuclear) starburst emission in
spirals increases from regions of lower to higher local galaxy surface density,
and from clusters with lower to higher central galaxy space density. We
conclude that tidal interactions are likely to be the main mechanism for the
transformation of spirals to S0s in clusters. Finally, for regions of
comparable local density, the frequency of tidally-induced starburst emission
is greater in clusters with higher central galaxy density. This implies that,
for a given local density, morphological transformation of disk galaxies
proceeds more rapidly in clusters of higher central galaxy density. This effect
is considered to be due to subcluster merging and could account for the
previously considered anomalous absence of a significant type - local surface
density relation for irregular clusters at intermediate redshift.

</DOC>
<DOC>
<DOCNO> 70900 </DOCNO>
Determination of the strong g-coupling and of the $\mu_{B^*B\gamma}-$


  We describe a calculation of the two-photon decays of heavy vector-mesons,
$B^*\to B\gamma\gamma$ and $D^*\to D\gamma\gamma$, by using the ``heavy meson
chiral Lagrangian''. The decay amplitudes are expressed in terms of the strong
coupling $g$ of the Lagrangian at various powers and the strength of the
anomalous magnetic dipole $\mu_{B^*B\gamma}$ (respectively $\mu_{D^*D}\gamma$).
In the charm case we are able to express the branching ratio $\Gamma(D^{*0}\to
D^0\gamma\gamma)/\Gamma(D^{*0})$ as a function of $g$ only and we expect it to
be in the $10^{-6}-10^{-5}$ range, depending on the value of $g$. The
determination of $\mu_{B^{*0}B^{0}\gamma},\mu_{B^{*+}B^+}\gamma$ requires a
more involved analysis, including the consideration of bremsstrahlung radiation
for the $B^{*+}\to B^+\gamma\gamma$ case.

</DOC>
<DOC>
<DOCNO> 121227 </DOCNO>
Profiles of thermal line emission from advection dominated accretion


  Recently, Narayan & Raymond (1999) proposed that the thermal emission lines
from the hot plasma in advection dominated accretion flows (ADAFs) are
potentially observable with the next generation of X-ray observatories, with
which the physical properties of some X-ray sources can be probed. In ADAFs,
the temperature of the ion is so high that the thermal broadening of the line
is important. We calculate the profiles of thermal line emission from ADAFs, in
which both the thermal and Doppler broadening have been considered. It is found
that the double-peaked profiles are present for high inclination angles between
the axis of disk and the line of sight. The double-peaked profiles are smeared
in low inclination cases, and completely disappear while the inclination angle
is less than $15^{\circ}$, where the thermal and turbulent broadening dominated
on the line profiles. We also note that the thermal line profile is affected by
the location of the transition radius of ADAF. The self-similar
height-integrated disk structure and the emissivity with power-law dependence
of radius are adopted in our calculations. The results obtained in this work
can be used as a diagnosis on the future X-ray observations of the thermal
lines. Some important physical quantities of ADAFs could be inferred from
future thermal line observations.

</DOC>
<DOC>
<DOCNO> 70501 </DOCNO>
Heavy-light mesons spectrum from the nonperturbative QCD in the einbein


  The spectrum of B and D mesons (including the low lying orbitally and
radially excited states) is calculated using the quark-antiquark Hamiltonian
derived from QCD in the einbein field formalism. Spin-spin and spin-orbit terms
due to the confinement and OGE interactions are taken into account as
perturbations. Results for the masses and splittings are confronted to the
experimental and recent lattice data and are demonstrated to be in a reasonable
agreement with both. We find that the orbital excitations with l=2 and l=3 for
D meson lie approximately in the same region as its first radial excitation
that might solve the mystery of the extremely narrow D(2637) state recently
claimed by DELPHI Collaboration.

</DOC>
<DOC>
<DOCNO> 69250 </DOCNO>
Absence of Gluonic Components in Axial and Tensor Mesons


  A quarkonium-gluonium mixing scheme previously developed to describe the
characteristic of the pseudoscalar mesons is applied to axial and tensor
mesons. The parameters of the model are determined by fitting the eigenvalues
of a mass matrix. The corresponding eigenvectors give the proportion of light
quarks, strange quarks and glueball in each meson. However the predictions of
the model for branching ratios and electromagnetic decays are incompatible with
the experimental results. These results suggest the absence of gluonic
components in the states of axial and tensor isosinglet mesons analyzed here.

</DOC>
<DOC>
<DOCNO> 12638 </DOCNO>
Phase separation in star polymer-colloid mixtures


  We examine the demixing transition in star polymer-colloid mixtures for star
arm numbers f=2,6,16,32 and different star-colloid size ratios. Theoretically,
we solve the thermodynamically self-consistent Rogers-Young integral equations
for binary mixtures using three effective pair potentials obtained from direct
molecular computer simulations. The numerical results show a spinodal
instability. The demixing binodals are approximately calculated, and found to
be consistent with experimental observations.

</DOC>
<DOC>
<DOCNO> 9545 </DOCNO>
Noise in neurons is message-dependent


  Neuronal responses are conspicuously variable. We focus on one particular
aspect of that variability: the precision of action potential timing. We show
that for common models of noisy spike generation, elementary considerations
imply that such variability is a function of the input, and can be made
arbitrarily large or small by a suitable choice of inputs. Our considerations
are expected to extend to virtually any mechanism of spike generation, and we
illustrate them with data from the visual pathway. Thus, a simplification
usually made in the application of information theory to neural processing is
violated: noise {\sl is not independent of the message}. However, we also show
the existence of {\sl error-correcting} topologies, which can achieve better
timing reliability than their components.

</DOC>
<DOC>
<DOCNO> 121529 </DOCNO>
Cosmological parameters from complementary observations of the Universe


  We use observational data on the large scale structure (LSS) of the Universe
measured over a wide range of scales from sub-galactic up to horizon scale and
on the cosmic microwave background anisotropies to determine cosmological
parameters within the class of adiabatic inflationary models. We show that a
mixed dark matter model with cosmological constant ($\Lambda$MDM model) and
parameters $\Omega_m=0.37^{+0.25}_{-0.15}$,
$\Omega_{\Lambda}=0.69^{+0.15}_{-0.20}$, $\Omega_{\nu}=0.03^{+0.07}_{-0.03}$,
$N_{\nu}=1$, $\Omega_b=0.037^{+0.033}_{-0.018}$, $n_s=1.02^{+0.09}_{-0.10}$,
$h=0.71^{+0.22}_{-0.19}$, $b_{cl}=2.4^{+0.7}_{-0.7}$ (1$\sigma$ confidence
limits) matches observational data on LSS, the nucleosynthesis constraint,
direct measurements of Hubble constant, the high redshift supernova type Ia
results and the recent measurements of the location and amplitude of the first
acoustic peak in the CMB anisotropy power spectrum. The best model is $\Lambda$
dominated (65% of the total energy density) and has slightly positive
curvature, $\Omega=1.06$. The clustered matter consists in 8% massive
neutrinos, 10% baryons and 82% cold dark matter (CDM). The upper 2$\sigma$
limit on the neutrino content can be expressed in the form
$\Omega_{\nu}h^2/N_{\nu}^{0.64}\le0.042$ or, via the neutrino mass,
$m_{\nu}\le4.0$eV. The upper 1(2)$\sigma$ limit for the contribution of a
tensor mode to the COBE DMR data is T/S$<1(1.5)$. Furthermore, it is shown that
the LSS observations together with the Boomerang (+MAXIMA-1) data on the first
acoustic peak rule out zero-$\Lambda$ models at more than $2\sigma$ confidence
limit.

</DOC>
<DOC>
<DOCNO> 69762 </DOCNO>
Topological Effects in Our Brane World From Extra Dimensions


  The theories in which our world presents a domain wall (brane) embedded in
large extra dimensions predict new types of topological defects. These defects
arise due to the fact that the brane on which we live spontaneously breaks
isometries of the extra space giving mass to some graviphotons. In many cases
the corresponding vacuum manifold has nontrivial homotopies -- this gives rise
to topologically stable defects in four dimensions, such as cosmic strings and
monopoles that carry gravimagnetic flux. The core structure of these defects is
somewhat peculiar. Due to the fact that the translation invariance in the extra
direction(s) is restored in their core, they act as "windows" to the extra
dimensions. We also discuss the corresponding analog of the Alice strings.
Encircling such an object one would get transported onto a parallel brane.

</DOC>
<DOC>
<DOCNO> 122738 </DOCNO>
Discovery of Spectral Transitions from Two Ultra-Luminous Compact X-Ray


  Two {\it ASCA} observations were made of two ultra-luminous compact X-ray
sources (ULXs), Source 1 and Source 2, in the spiral galaxy IC 342. In the 1993
observation, Source 2 showed a 0.5--10 keV luminosity of $6 \times 10^{39}$
ergs s$^{-1}$ (assuming a distance of 4.0 Mpc), and a hard power-law spectrum
of photon index $\sim 1.4$. As already reported, Source 1 was $\sim 3$ times
brighter on that occasion, and exhibited a soft spectrum represented by a
multi-color disk model of inner-disk temperature $ \sim 1.8$ keV. The second
observation made in February 2000 revealed that Source 1 had made a transition
into a hard spectral state, while Source 2 into a soft spectral state. The ULXs
are therefore inferred to exhibit two distinct spectral states, and sometimes
make transitions between them. These results significantly reinforce the
scenario which describes ULXs as mass-accreting black holes.

</DOC>
<DOC>
<DOCNO> 101832 </DOCNO>
On the theorem converse to Jordan's curve theorem


  Theorem converse to Jordan's curve theorem says that {\it if a compact set
$K$ has two complementary domains in $R^{2}$, from each of which it is at every
point accessible, it is a simple closed curve}.
  We show that the requirement of this theorem that {\it all} points of $K$
were accessible from {\it both} complementary domains is surplus and prove one
generalization of this theorem.

</DOC>
<DOC>
<DOCNO> 69785 </DOCNO>
On the spectrum of Ultrahigh Energy Cosmic Rays and the Gamma Ray Burst


  It has been suggested that cosmological gamma-ray bursts (GRBs) can produce
the observed flux of cosmic rays at the highest energies. However, recent
studies of GRBs indicate that their redshift distribution likely follows that
of the average star formation rate and that GRBs were more numerous at high
redshifts. As a consequence, we show that photomeson production energy losses
suffered by ultrahigh energy cosmic rays coming from GRBs would produce too
sharp a spectral high energy cutoff to be consistent with the air shower data.
Furthermore, we show that cosmological GRBs fail to supply the energy input
required to account for the cosmic ray flux above 10 EeV by a factor of
100-1000.

</DOC>
<DOC>
<DOCNO> 99413 </DOCNO>
Quotients of Divisorial Toric Varieties


  We consider subtorus actions on divisorial toric varieties. Here
divisoriality means that the variety has many Cartier divisors like
quasiprojective and smooth ones. We characterize when a subtorus action on such
a toric variety admits a categorical quotient in the category of divisorial
varieties. Our result generalizes previous statements for the quasiprojective
case. An important tool for the proof is a universal reduction of an arbitrary
toric variety to a divisorial one. This is done in terms of support maps, a
notion generalizing support functions on a polytopal fan. A further essential
step is the decomposition of a given subtorus invariant regular map to a
divisorial variety into an invariant toric part followed by a non-toric part.

</DOC>
<DOC>
<DOCNO> 40610 </DOCNO>
Semi-Contained Neutrino Events in MACRO


  Updated results are presented of low-energy ($\bar{E_\nu} \sim 5 GeV$)
neutrino interactions observed by the MACRO detector. Two analyses (of
different topologies) are presented; individually, and especially in their
ratio, they are inconsistent with no oscillations and consistent with maximal
mixing at $\Delta m^2$ of a few times $10^{-3}$.

</DOC>
<DOC>
<DOCNO> 122724 </DOCNO>
Lessons from lensed Lyman break galaxies: can dusty Lyman break galaxies


  Can the submillimetre counts and background be produced by applying a locally
derived extinction correction to the population of Lyman break galaxies? We
investigate the submillimetre emission of two strongly lensed Lyman break
galaxies (MS1512+36-cB58 and MS1358+62-G1) and find that the procedure that is
used to predict the submillimetre emission of the Lyman break galaxy population
overpredicts the observed 850 micron fluxes by a factor of up to 14. This
result calls for caution in applying local correlations to distant galaxies. It
also shows that large extinction corrections on Lyman break galaxies should be
viewed with skepticism. It is concluded that the Lyman break galaxies may
contribute to the submillimetre background at the 25 to 50% level. The brighter
submillimetre galaxies making up the rest of the background are either not
detected in optical surveys, or if they are detected, their submillimetre
emission cannot be reliably estimated from their rest-frame ultraviolet
properties.

</DOC>
<DOC>
<DOCNO> 67827 </DOCNO>
Sphaleron rate in the symmetric electroweak phase


  Recently Bodeker has presented an effective infrared theory for the dynamics
of Yang-Mills theory, suitable for studying the rate of baryon number violation
in the early universe. We extend his theory to include Higgs fields, and study
how much the Higgs affects the baryon number violation rate in the symmetric
phase, at the phase coexistence temperature of a first order electroweak phase
transition. The rate is about 20% smaller than in pure Yang-Mills theory. We
also analyze the sphaleron rate in the analytic crossover regime. Our treatment
relies on the ergodicity conjecture for 3-D scalar $\phi^4$ theory.

</DOC>
<DOC>
<DOCNO> 12725 </DOCNO>
Rotating Superconductors and the London Moment: Thermodynamics versus


  Comparing various microscopic theories of rotating superconductors to the
conclusions of thermodynamic considerations, we traced their marked difference
to the question of how some thermodynamic quantities (the electrostatic and
chemical potentials) are related to more microscopic ones: The electron's the
work function, mean-field potential and Fermi energy -- certainly a question of
general import.
  After the correct identification is established, the relativistic correction
for the London Moment is shown to vanish, with the obvious contribution from
the Fermi velocity being compensated by other contributions such as
electrostatics and interactions.

</DOC>
<DOC>
<DOCNO> 118233 </DOCNO>
Ultra-High-Energy Cosmic Ray Acceleration by Magnetic Reconnection in


  We here investigate the possibility that the ultra-high energy cosmic ray
(UHECR) events observed above the GZK limit are mostly protons accelerated in
reconnection sites just above the magnetosphere of newborn millisecond pulsars
which are originated by accretion induced collapse (AIC). We show that
AIC-pulsars with surface magnetic fields $10^{12} G < B_{\star} \lesssim
10^{15}$ G and spin periods $1 ms \lesssim P_{\star} < 60 ms$, are able to
accelerate particles to energies $\geq 10^{20}$ eV. Because the expected rate
of AIC sources in our Galaxy is very small (\sim 10^{-5} yr^{-1}), the
corresponding contribution to the flux of UHECRs is neglegible, and the total
flux is given by the integrated contribution from AIC sources produced by the
distribution of galaxies located within the distance which is unaffected by the
GZK cutoff ($\sim 50$ Mpc). We find that the reconnection efficiency factor
needs to be $\xi \gtrsim 0.1$ in order to reproduce the observed flux of
UHECRs.

</DOC>
<DOC>
<DOCNO> 9647 </DOCNO>
Applicability of Fermi golden rule and possibility of low-field runaway


  In order to justify applicability of the standard approach of perturbation
theory for the description of transport phenomena in wide-band polar
semiconductors with strong electron-phonon interactions, we have compared
dependences of energy losses to the lattice on the electron drift velocity
obtained for different materials in the frameworks of (a) a perturbative
approach based on calculation of the scattering rates from Fermi's golden rule
and (b) a non-perturbative approach based on the path-integral formalism of
Thornber and Feynman. Our results reveal that despite strong electron-phonon
coupling in GaN and AlN such that intercollision times become of the order of
the period of phonon oscillation, standard perturbative treatment can still be
applied successfully for this type of material. Our findings also indicate
possibility for unique long-distance runaway transport in nitrides which may
occur at the pre-threshold electric fields. Polaron ground state energy and
effective masses are calculated for GaN and AlN as well as for GaAs and Al_2
O_3.

</DOC>
<DOC>
<DOCNO> 178677 </DOCNO>
Collective states from random interactions


  The anharmonic vibrator and rotor regions in nuclei are investigated in the
framework of the interacting boson model using an ensemble of random one- and
two-body interactions. Despite the randomness of the interactions (in sign and
size) we find a predominance of L(P)=0(+) ground states and strong evidence for
the occurrence of both vibrational and rotational band structure.

</DOC>
<DOC>
<DOCNO> 151534 </DOCNO>
Paramagnetic dominance, the sign of the beta function and UV/IR mixing


  U(1) gauge theory on non-commutative Minkowski space-time in the Feynman-'t
Hooft background gauge is studied. In particular, UV divergences and
non-commutative IR divergent contributions to the two, three and four-point
functions are explicitly computed at one loop. We show that the negative sign
of the beta function results from paramagnetism --producing UV charge
anti-screening-- prevailing over diamagnetism --giving rise toUV charge
screening. This dominance in the field theory setting corresponds to tachyon
magnification dominance in the string theory framework. Our calculations
provide an explicit realization of UV/IR mixing and lead to an IR
renormalization of the coupling constant, where now paramagnetic contributions
produce screening and diamagnetic contributions anti-screening.

</DOC>
<DOC>
<DOCNO> 10233 </DOCNO>
Spin and Charge Luttinger-Liquid Parameters of the One-Dimensional


  Low-energy properties of the homogeneous electron gas in one dimension are
completely described by the group velocities of its charge (plasmon) and spin
collective excitations. Because of the long range of the electron-electron
interaction, the plasmon velocity is dominated by an electrostatic contribution
and can be estimated accurately. In this Letter we report on Quantum Monte
Carlo simulations which demonstrate that the spin velocity is substantially
decreased by interactions in semiconductor quantum wire realizations of the
one-dimensional electron liquid.

</DOC>
<DOC>
<DOCNO> 119547 </DOCNO>
Simulated Cluster Archive: A Computational Catalog of X-Ray Clusters in


  We have simulated the evolution of a large sample of X-ray clusters in a
Lambda-CDM universe at high spatial resolution using adaptive mesh refinement
and placed the results in an online archive for public access. The Simulated
Cluster Archive website http://sca.ncsa.uiuc.edu provides tools for interactive
2D and 3D analysis of gas and dark matter fields, X-ray and SZ imaging, and
data export. We encourage community use and solicit their feedback.

</DOC>
<DOC>
<DOCNO> 80710 </DOCNO>
ADHM Construction of Instantons on the Torus


  We apply the ADHM instanton construction to SU(2) gauge theory on T^n x
R^(4-n)for n=1,2,3,4. To do this we regard instantons on T^n x R^(4-n) as
periodic (modulo gauge transformations) instantons on R^4. Since the R^4
topological charge of such instantons is infinite the ADHM algebra takes place
on an infinite dimensional linear space. The ADHM matrix M is related to a Weyl
operator (with a self-dual background) on the dual torus tilde T^n. We
construct the Weyl operator corresponding to the one-instantons on T^n x
R^(4-n). In order to derive the self-dual potential on T^n x R^(4-n) it is
necessary to solve a specific Weyl equation. This is a variant of the Nahm
transformation. In the case n=2 (i.e. T^2 x R^2) we essentially have an
Aharonov Bohm problem on tilde T^2. In the one-instanton sector we find that
the scale parameter, lambda, is bounded above, (lambda)^2 tv<4 pi, tv being the
volume of the dual torus tilde T^2.

</DOC>
<DOC>
<DOCNO> 178982 </DOCNO>
Electromagnetic K+ production on the deuteron with hyperon recoil


  Photo- and electroproduction processes of K+ on the deuteron are investigated
theoretically. Modern hyperon-nucleon forces as well as an updated kaon
production operator on the nucleon are used. Sizable effects of the
hyperon-nucleon final state interaction are seen in various observables.
Especially the photoproduction double polarization observable C_z is shown to
provide a handle to distinguish different hyperon-nucleon force models.

</DOC>
<DOC>
<DOCNO> 83513 </DOCNO>
Hamilton Circuits in Graphs and Directed Graphs


  We give polynomial-time algorithms for obtaining hamilton circuits in random
graphs, G, and random directed graphs, D. If n is finite, we assume that G or D
contains a hamilton circuit. If G is an arbitrary graph containing a hamilton
circuit, we conjecture that Algorithm G always obtains a hamilton circuit in
polynomial time.

</DOC>
<DOC>
<DOCNO> 13263 </DOCNO>
The excitonic collapse of higher Landau level fractional quantum Hall


  The scarcity of the fractional quantum Hall effect in higher Landau levels is
a most intriguing fact when contrasted with its great abundance in the lowest
Landau level. This paper shows that a suppression of the hard core repulsion in
going from the lowest Landau level to higher Landau levels leads to a collapse
of the energy of the neutral excitation, destabilizing all fractional states in
the third and higher Landau levels, and almost all in the second Landau level.
The remaining fractions are in agreement with those observed experimentally.

</DOC>
<DOC>
<DOCNO> 120254 </DOCNO>
Pre-Orion Cores in the Trifid Nebula


  The Trifid nebula is a young HII region undergoing a burst of star formation.
In this article, we report on far-infrared and millimeter continuum and line
observations of several massive and bright protostellar sources in the vicinity
of the exciting star fo the nebula, just behind the ionization front. These
objects are probably young protostars (Class 0) and are associated with very
massive cores (M ~ 8-90 Msol) powering young energetic outflows. Analysis of
the far-infrared emission in the 45-200 micron range from ISO/LWS data shows
that they are embedded in cold dense material. Inspection of their physical
properties suggest that they are similar to the dust protostellar cores
observed in Orion, although at an earlier evolutionary "Pre-Orion" stage. The
cores are embedded in a compressed layer of dense gas. Based on comparison with
the models, we find that the cores could have formed from the fragmentation of
the layer and that the birth of the protostars was triggered by the expansion
of the Trifid nebula.

</DOC>
<DOC>
<DOCNO> 83163 </DOCNO>
Proving Failure of Queries for Definite Logic Programs Using XSB-Prolog


  Proving failure of queries for definite logic programs can be done by
constructing a finite model of the program in which the query is false. A
general purpose model generator for first order logic can be used for this. A
recent paper presented at PLILP98 shows how the peculiarities of definite
programs can be exploited to obtain a better solution. There a procedure is
described which combines abduction with tabulation and uses a meta-interpreter
for heuristic control of the search. The current paper shows how similar
results can be obtained by direct execution under the standard tabulation of
the XSB-Prolog system. The loss of control is compensated for by better
intelligent backtracking and more accurate failure analysis.

</DOC>
<DOC>
<DOCNO> 11126 </DOCNO>
Andreev reflection at point contacts with heavy-fermion UBe13 ?


  We comment on a recent Letter by Waelti et al. (PRL 84, 5616 (2000)) on
'Spectroscopic evidence for unconventional superconductivity in UBe13'. We show
- by using the basic Wexler formula - that it is unlikely to observe Andreev
reflection at point contacts between UBe13 and a normal metal. The large
superconducting anomalies usually found for those contacts are mainly due to
the resistive Maxwell resistance vanishing below Tc of UBe13.

</DOC>
<DOC>
<DOCNO> 100952 </DOCNO>
Construction of commuting difference operators for multiplicity free


  We study root systems equipped with a basis of dominant weights such that
certain axioms hold. This formalism allows to define a linear basis P of the
space of Weyl group invariant polynomials. This basis is actually a family
depending on at least one parameter. Our main result is the construction of
difference operators which are simultaneously diagonalized by P. From this,
Pieri type rules are derived. This generalizes results for shifted Jack
polynomials.
  Even though the approach is purely combinatorial, the main motivation comes
from multiplicity free actions of reductive groups on vector spaces. Then the
algebra of invariant differential operators has a distinguished basis, the
Capelli operators, which gives rise to a basis P as above. The paper ends with
a comprehensive table detailing the combinatorial structure of multiplicity
free actions.

</DOC>
<DOC>
<DOCNO> 13186 </DOCNO>
Dynamics of directed graphs: the world-wide Web


  We introduce and simulate a growth model of the world-wide Web based on the
dynamics of outgoing links that is motivated by the conduct of the agents in
the real Web to update outgoing links (re)directing them towards constantly
changing selected nodes. Emergent statistical correlation between the
distributions of outgoing and incoming links is a key feature of the dynamics
of the Web. The growth phase is characterized by temporal fractal structures
which are manifested in the hierarchical organization of links. We obtain
quantitative agreement with the recent empirical data in the real Web for the
distributions of in- and out-links and for the size of connected component. In
a fully grown network of $N$ nodes we study the structure of connected clusters
of nodes that are accessible along outgoing links from a randomly selected
node. The distributions of size and depth of the connected clusters with a
giant component exhibit supercritical behavior. By decreasing the control
parameter---average fraction $\beta $ of updated and added links per time
step---towards $\beta_c(N) < 10% $ the Web can resume a critical structure with
no giant component in it. We find a different universality class when the
updates of links are not allowed, i.e., for $\beta \equiv 0$, corresponding to
the network of science citations.

</DOC>
<DOC>
<DOCNO> 151166 </DOCNO>
SU(2) WZW D-branes and quantized worldvolume U(1) flux on S^2


  We discuss possible D-brane configurations on SU(2) group manifolds in the
sigma model approach. When we turn the boundary conditions of the spacetime
fields into the boundary gluing conditions of chiral currents, we find that for
all D-branes except the spherical D2-branes, the gluing matrices R^a_{b} depend
on the fields, so the chiral Kac-Moody symmetry is broken, but conformal
symmetry is maintained. Matching the spherical D2-branes derived from the sigma
model with those from the boundary state approach we obtain a U(1) field
strength that is consistent with flux quantization.

</DOC>
<DOC>
<DOCNO> 40486 </DOCNO>
Heavy --> Light semileptonic decays of pseudoscalar mesons from lattice


  We have computed the form factors for B --> pi and D --> K(pi) semileptonic
decays on the lattice by using full non-perturbative O(a) improvement, in the
quenched approximation. Our results are expressed in terms of few parameters
which describe the q^2-dependence and normalization of the form factors.

</DOC>
<DOC>
<DOCNO> 120209 </DOCNO>
Ionization, Kinematics, and Extent of the Diffuse Ionized Gas Halo of


  We present key results from deep spectra of the Diffuse Ionized Gas (DIG)
halo of the edge-on galaxy NGC 5775. [NII]6583 has been detected up to about
z=13 kpc above the plane in one of two vertically oriented long slits -- making
this the spiral galaxy with the greatest spectroscopically detected halo extent
in emission. Key diagnostic line ratios have been measured up to about z=8 kpc,
allowing the source of ionization and physical state to be probed. Ionization
by a dilute radiation field from massive stars in the disk can explain some of
the line ratio behavior, but departures from this picture are clearly
indicated, most strongly by the rise of [OIII]/Halpha with z. Velocities of the
gas in both slits approach the systemic velocity of the galaxy at several kpc
above the plane. We interpret this trend as a decrease in rotation velocity
with z, with essentially no rotation at heights of several kpc. Such a trend
was observed in the edge-on galaxy NGC 891, but here much more dramatically.
This falloff is presumably due to the gravitational potential changing with z,
but will also depend on the hydrodynamic nature of the disk-halo cycling of gas
and projection effects. More detailed modeling of the ionization and kinematics
of this and other edge-ons will be presented in future papers.

</DOC>
<DOC>
<DOCNO> 84421 </DOCNO>
A Spacetime Foam Approach to the Schwarzschild-de Sitter Entropy


  The entropy for a black hole in a de Sitter space is approached within the
framework of spacetime foam. A simple model, made by $N$ wormholes in a
semiclassical approximation, is taken under examination to compute the entropy
for such a case. An extension to the extreme case when the black hole and
cosmological horizons are equal is discussed.

</DOC>
<DOC>
<DOCNO> 9932 </DOCNO>
The role of occupied d states in the relaxation of hot electrons in Au


  We present first-principles calculations of electron-electron scattering
rates of low-energy electrons in Au. Our full band-structure calculations
indicate that a major contribution from occupied d states participating in the
screening of electron-electron interactions yields lifetimes of electrons in Au
with energies of $1.0-3.0 {\rm eV}$ above the Fermi level that are larger than
those of electrons in a free-electron gas by a factor of $\sim 4.5$. This
prediction is in agreement with a recent experimental study of ultrafast
electron dynamics in Au(111) films (J. Cao {\it et al}, Phys. Rev. B {\bf 58},
10948 (1998)), where electron transport has been shown to play a minor role in
the measured lifetimes of hot electrons in this material.

</DOC>
<DOC>
<DOCNO> 121277 </DOCNO>
Construction of Cosmic String Induced Temperature Anisotropy Maps with


  We use the publicly available code CMBFAST as modified by L. Pogosian and T.
Vachaspati to simulate the effects of wiggly cosmic strings on the Cosmic
Microwave Background (CMB). Using the modified CMBFAST code which takes into
account vector modes and models wiggly cosmic strings by the one scale model,
we go beyond the angular power spectrum to construct CMB temperature maps with
resolution of a few degrees. The statistics of these maps are then studied
using conventional and recently proposed statistical tests optimized for the
detection of hidden temperature discontinuities induced by the
Gott-Kaiser-Stebbins effect. We show however, that these realistic maps can not
be distinguished in a statistically significant way from purely Gaussian maps
with identical power spectrum.

</DOC>
<DOC>
<DOCNO> 69618 </DOCNO>
Solving the Gravitino Problem by Axino


  In a large class of supersymmetric (SUSY) axion model the mass of axino
$\axino$ (a fermionic superpartner of the axion) is predicted as $m_{\axino}
\lesssim {\cal O}(1)$ keV. Thus, the axino is the lightest SUSY particle (LSP).
We pointed out that such a light axino provides a natural solution to the
gravitino problem, if the gravitino is the next LSP. We derive a constraint on
the reheating temperature $T_R$ of inflation, $T_R \lesssim 10^{15}$ GeV for
the gravitino mass $m_{3/2} \simeq 100$ GeV, which is much weaker than that
obtained in the minimal SUSY standard model.

</DOC>
<DOC>
<DOCNO> 99591 </DOCNO>
Entropy of Bogoliubov automorphisms of CAR and CCR algebras with respect


  We compute the dynamical entropy of Bogoliubov automorphisms of CAR and CCR
algebras with respect to arbitrary gauge-invariant quasi-free states. This
completes the research started by Stormer and Voiculescu, and continued in
works of Narnhofer-Thirring and Park-Shin.

</DOC>
<DOC>
<DOCNO> 68254 </DOCNO>
Effects of New Gravitational Interactions on Neutrinoless Double Beta


  It has recently been proposed that violations of Lorentz invariance or
violations of the equivalence principle can be constrained from the
non-observation of neutrinoless double beta decay. We generalize this analysis
to all possible new gravitational interactions and discuss briefly the
constraints for different cases.

</DOC>
<DOC>
<DOCNO> 178739 </DOCNO>
Energy and Centrality Dependence of Rapidity Densities at RHIC


  The energy and centrality dependence of the charged multiplicity per
participant nucleon is shown to be able to differentiate between final-state
saturation and fixed scale pQCD models of initial entropy production in
high-energy heavy-ion collisions. The energy dependence is shown to test the
nuclear enhancement of the mini-jet component of the initial conditions, while
the centrality dependence provides a key test of whether gluon saturation is
reached at RHIC energies. HIJING model predicts that the rapidity density per
participant increases with centrality, while the saturation model prediction is
essentially independent of centrality.

</DOC>
<DOC>
<DOCNO> 80802 </DOCNO>
Randomness on the Lattice


  In this lecture we review recent lattice QCD studies of the statistical
properties of the eigenvalues of the QCD Dirac operator. We find that the
fluctuations of the smallest Dirac eigenvalues are described by chiral Random
Matrix Theories with the global symmetries of the QCD partition function.
Deviations from chiral Random Matrix Theory beyond the Thouless energy can be
understood analytically by means of partially quenched chiral perturbation
theory.

</DOC>
<DOC>
<DOCNO> 119419 </DOCNO>
Nereid Has Complex Large-Amplitude Photometric Variability (Due to


  We report on 224 photometric measurements of Nereid, a small outer satellite
of Neptune. Our photometry covers 64 nights from 1987 to 1997 and is primarily
in the V-band; we also have 20 measurements in the U, B, R, and I bands. (1)
Nereid displays large-amplitude brightness variations with a total amplitude of
1.83 mag on time scales ranging from a few hours to roughly a year. (2) The
amplitude as well as the time scale of variation changes greatly from year to
year. (3) Nereid's variability is caused by high contrast albedo features along
with rotational modulation. (4) The changing amplitudes and time scales
demonstrate that the direction and magnitude of Nereid's rotational angular
momentum vector is not constant. (5) Such changes are predicted to arise from
chaotic rotation during every periapse passage provided that Nereid is more
than about 1% nonspherical and is spinning slowly. The match between prediction
and observation could be taken as strong evidence for chaotic rotation of
Nereid. However, the intranight variability cannot be readily explained by
chaotic rotation. (6) The colors of Nereid are U-V=0.84+-0.05, B-V=0.71+-0.04,
V-R=0.44+-0.03, V-I=0.72+-0.05, and V-K=1.6. (7) Nereid is likely either an
inner moon of Neptune kicked to its current orbit or a captured Kuiper Belt
Object or centaur, with the latter possibility being strongly preferred.

</DOC>
<DOC>
<DOCNO> 118579 </DOCNO>
The HII Region KR 140: Spontaneous Formation of a High Mass Star


  We have used a multiwavelength data set from the Canadian Galactic Plane
Survey (CGPS) to study the Galactic HII region KR 140, both on the scale of the
nebula itself and in the context of the star forming activity in the nearby
W3/W4/W5 complex of molecular clouds and HII regions. From both radio and
infrared data we have found a covering factor of about 0.5 for KR 140 and we
interpret the nebula as a bowl-shaped region viewed close to face on.
Extinction measurements place the region on the near side of its parent
molecular cloud. The nebula is kept ionized by one O8.5 V(e) star, VES 735,
which is less than a few million years old. CO data show that VES 735 has
disrupted much of the original molecular cloud for which the estimated mass and
density are about 5000 $M_{\odot}$ and 100 cm$^{-3}$, respectively. KR 140 is
isolated from the nearest star forming activity, in W3. Our data suggest that
KR 140 is an example of spontaneous (i.e., non-triggered) formation of,
unusually, a high mass star.

</DOC>
<DOC>
<DOCNO> 9397 </DOCNO>
Peculiarities of anharmonic lattice dynamics and thermodynamics of


  The calculations are performed for a broad range of the properties of Ca and
Sr in the fcc and bcc phases. A detailed information on the magnitude and
character of temperature dependence of anharmonic effects in the lattice
dynamics over the entire Brillouin zone (frequency shifts and phonon damping,
Gruneisen parameters) is given. A detailed comparison of the computational
results for the heat capacity and thermal expansion with the experimental data
is carried out; the theoretical results are in good agreement with the
experiment.

</DOC>
<DOC>
<DOCNO> 70479 </DOCNO>
A Relativistic Quark Model for Mesons with an Instanton-Induced


  We present new results of a relativistic quark model based on the
Bethe-Salpeter equation in its instantaneous approximation. Assuming a linearly
rising confinement potential with an appropriate spinorial structure in Dirac
space and adopting a residual interaction based on instanton effects, we can
compute masses of the light mesons up to highest observed angular momenta with
a natural solution of the $U_A(1)$ problem. The calculated ground states masses
and the radial excitations describe the experimental results well. In this
paper, we will also discuss our results concerning numerous meson decay
properties. For processes like $\pi^+/K^+\to e^+\nu_e\gamma$ and
$0^-\to\gamma\gamma$ at various photon virtualities, we find a good agreement
with experimental data. We will also comment on the form factors of the
$K_{\ell 3}$ decay and on the decay constants of the $\pi$, $K$ and $\eta$
mesons. For the sake of completeness, we will furthermore present the
electromagnetic form factors of the charged $\pi$ and $K$ mesons as well as a
comparison of the radiative meson decay widths with the most recent
experimental data.

</DOC>
<DOC>
<DOCNO> 13000 </DOCNO>
Exponential Gain in Quantum Computing of Quantum Chaos and Localization


  We present a quantum algorithm which simulates the quantum kicked rotator
model exponentially faster than classical algorithms. This shows that important
physical problems of quantum chaos, localization and Anderson transition can be
modelled efficiently on a quantum computer. We also show that a similar
algorithm simulates efficiently classical chaos in certain area-preserving
maps.

</DOC>
<DOC>
<DOCNO> 121660 </DOCNO>
Parallax and Kinematics of PSR B0919+06 from VLBA Astrometry and


  Results are presented from a long-term astrometry program on PSR B0919+06
using the NRAO Very Long Baseline Array. With ten observations (seven epochs)
between 1994--2000, we measure a proper motion of 18.35 +/- 0.06 mas/yr in RA,
86.56 +/- 0.12 mas/yr in Dec, and a parallax of 0.83 +/- 0.13 mas (68%
confidence intervals). This yields a pulsar distance of 1.21 +/- 0.19 kpc,
making PSR B0919+06 the farthest pulsar for which a trigonometric parallax has
been obtained, and the implied pulsar transverse speed is 505 +/- 80 km/s.
Combining the distance estimate with interstellar scintillation data spanning
20 years, we infer the existence of a patchy or clumpy scattering screen along
the line of sight in addition to the distributed electron density predicted by
models for the Galaxy, and constrain the location of this scattering region to
within about 250 parsecs of the Sun. Comparison with the lines of sight towards
other pulsars in the same quadrant of the Galaxy permits refinement of our
knowledge of the local interstellar matter in this direction.

</DOC>
<DOC>
<DOCNO> 170289 </DOCNO>
Monge Metric on the Sphere and Geometry of Quantum States


  Topological and geometrical properties of the set of mixed quantum states in
the N-dimensional Hilbert space are analysed. Assuming that the corresponding
classical dynamics takes place on the sphere we use the vector SU(2) coherent
states and the generalised Husimi distributions to define the Monge distance
between arbitrary two density matrices. The Monge metric has a simple
semiclassical interpretation and induces a non-trivial geometry. Among all pure
states the distance from the maximally mixed state \rho_*, proportional to the
identity matrix, admits the largest value for the coherent states, while the
delocalized 'chaotic' states are close to \rho_*. This contrasts the geometries
induced by the standard (trace, Hilbert-Schmidt or Bures) metrics, where the
distance from \rho_* is the same for all pure states. We discuss possible
physical consequences including unitary time evolution and the process of
decoherence. We introduce also a simplified Monge metric, defined in the space
of pure quantum states, and more suitable for numerical computation.

</DOC>
<DOC>
<DOCNO> 117106 </DOCNO>
Definition of the elements of length and time by means of photon


  It is considered the procedure of definition of the elements of length and
time by means of photon. In order to define the element of length one needs an
a priori given element of time. In order to define the element of time one
needs an a priori given element of length. It is taken the laboratory time and
length as a priori given time and length respectively. It is defined the
elements of length and time for the reference frame moving with the velocity
$v$ and for the reference frame with the gravitational potential $\Phi$.

</DOC>
<DOC>
<DOCNO> 80929 </DOCNO>
Domain Wall Fermion Study of Scaling in Non-perturbative Renormalization


  We compute non-perturbatively the renormalization coefficients of scalar and
pseudoscalar operators, local vector and axial currents, conserved vector and
axial currents, and $O^{\Delta S=2}_{LL}$ over a wide range of energy scales
using a scaling technique that connects the results of simulations at different
values of coupling $\beta$. We use the domain wall fermion formulation in the
quenched approximation at a series of three values of $\beta = 6.0, 6.45, 7.05$
corresponding to lattice spacing scaling by factors of two.

</DOC>
<DOC>
<DOCNO> 118921 </DOCNO>
On the pair-electromagnetic pulse from an electromagnetic Black Hole


  The interaction of an expanding Pair-Electromagnetic pulse (PEM pulse) with a
shell of baryonic matter surrounding a Black Hole with electromagnetic
structure (EMBH) is analyzed for selected values of the baryonic mass at
selected distances well outside the dyadosphere of an EMBH. The dyadosphere,
the region in which a super critical field exists for the creation of
electron-positron pairs, is here considered in the special case of a
Reissner-Nordstrom geometry. The interaction of the PEM pulse with the baryonic
matter is described using a simplified model of a slab of constant thickness in
the laboratory frame (constant-thickness approximation) as well as performing
the integration of the general relativistic hydrodynamical equations. The
validation of the constant-thickness approximation, already presented in a
previous paper Ruffini, et al.(1999) for a PEM pulse in vacuum, is here
generalized to the presence of baryonic matter. It is found that for a baryonic
shell of mass-energy less than 1% of the total energy of the dyadosphere, the
constant-thickness approximation is in excellent agreement with full general
relativistic computations. The approximation breaks down for larger values of
the baryonic shell mass, however such cases are of less interest for observed
Gamma Ray Bursts (GRBs). On the basis of numerical computations of the slab
model for PEM pulses, we describe (i) the properties of relativistic evolution
of a PEM pulse colliding with a baryonic shell; (ii) the details of the
expected emission energy and observed temperature of the associated GRBs for a
given value of the EMBH mass; 10^3 solar masses, and for baryonic mass-energies
in the range 10^{-8} to 10^{-2} the total energy of the dyadosphere.

</DOC>
<DOC>
<DOCNO> 116729 </DOCNO>
Beam Profile Monitors in the Nlcta


  The transverse current profile in the Next Linear Collider Test Accelerator
(NLCTA) electron beam can be monitored at several locations along the beam line
by means of profile monitors. These consist of insertable phosphor screens,
light collection and transport systems, CID cameras, a frame-grabber, and PC
and VAX based image analysis software. In addition to their usefulness in
tuning and steering the accelerator, the profile monitors are utilized for
emittance measurement. A description of these systems and their performance is
presented.

</DOC>
<DOC>
<DOCNO> 9703 </DOCNO>
Systematic evolution of the magnetotransport properties of


  Recently we have succeeded in growing a series of high-quality
Bi_{2}Sr_{2-x}La_{x}CuO_{6} crystals in a wide range of carrier concentrations.
The data of \rho_{ab}(T) and R_H(T) of those crystals show behaviors that are
considered to be "canonical" to the cuprates. The optimum zero-resistance T_c
has been raised to as high as 38 K, which is almost equal to the optimum T_c of
La_{2-x}Sr_{x}CuO_{4}.

</DOC>
<DOC>
<DOCNO> 70360 </DOCNO>
Correlating the Higgs and Kaon Sector CP Violations


  Taking the most general two-doublet models with explicit CP violation in the
Higgs sector but no phase in the CKM matrix, we determine the correlation
between the Higgs and Kaon sectors using the experimental values of $\Delta
M_K$ and $\epsilon_K$. It is found that: there is a direct correlation between
strength of FCNC couplings and the Higgs masses, and the lightest Higgs is
nearly pure CP-even, but this small CP-odd composition gives large enough
contribution to $\epsilon_K$.

</DOC>
<DOC>
<DOCNO> 84306 </DOCNO>
See Project for Testing Gravity in Space: Current Status and New


  We describe some new estimates concerning the recently proposed SEE
(Satellite Energy Exchange) experiment for measuring the gravitational
interaction parameters in space. The experiment entails precision tracking of
the relative motion of two test bodies (a heavy "Shepherd", and a light
"Particle") on board a drag-free capsule. The new estimates include (i) the
sensitivity of Particle trajectories and G measurement to the Shepherd
quadrupole moment uncertainties; (ii) the measurement errors of G and the
strength of a putative Yukawa-type force whose range parameter $\lambda$ may be
either of the order of a few metres or close to the Earth radius; (iii) a
possible effect of the Van Allen radiation belts on the SEE experiment due to
test body electric charging

</DOC>
<DOC>
<DOCNO> 9754 </DOCNO>
Shot Noise Suppression at 2D Hopping


  We have used Monte Carlo simulation to calculate the shot noise intensity
$S_I(\omega)$ at 2D hopping using two models: a slanted lattice of localized
sites with equal energies and a set of localized sites with random positions
and energies. For wide samples we have found a similar dependence of the Fano
factor $F \equiv S_I(0)/2eI$ on the sample length $L$: $F \propto L^{-\alpha}$
where $\alpha =0.85 \pm 0.02$ and $\alpha = 0.85\pm 0.07$ in uniform and random
models, respectively. Moreover, at least for the uniform model, all the data
for $F$ as the function of sample length $L$ and width $W$ may be presented via
a single function of the ratio $W/L^{\beta}$, with $\beta = 2\alpha-1 \approx
0.7$. This relation has been interpreted using a simple scaling theory.

</DOC>
<DOC>
<DOCNO> 80801 </DOCNO>
Discrete Symmetry Enhancement in Nonabelian Models and the Existence of


  We study the universality between a discrete spin model with icosahedral
symmetry and the O(3) model in two dimensions. For this purpose we study
numerically the renormalized two-point functions of the spin field and the four
point coupling constant. We find that those quantities seem to have the same
continuum limits in the two models. This has far reaching consequences, because
the icosahedron model is not asymptotically free in the sense that the coupling
constant proposed by L"uscher, Weisz and Wolff [1] does not approach zero in
the short distance limit. By universality this then also applies to the O(3)
model, contrary to the predictions of perturbation theory.

</DOC>
<DOC>
<DOCNO> 10425 </DOCNO>
Traveling Waves, Front Selection, and Exact Nontrivial Exponents in a


  We study a random bisection problem where an initial interval of length x is
cut into two random fragments at the first stage, then each of these two
fragments is cut further, etc. We compute the probability P_n(x) that at the
n-th stage, each of the 2^n fragments is shorter than 1. We show that P_n(x)
approaches a traveling wave form, and the front position x_n increases as
x_n\sim n^{\beta}{\rho}^n for large n. We compute exactly the exponents
\rho=1.261076... and \beta=0.453025.... as roots of transcendental equations.
We also solve the m-section problem where each interval is broken into m
fragments. In particular, the generalized exponents grow as \rho_m\approx
m/(\ln m) and \beta_m\approx 3/(2\ln m) in the large m limit. Our approach
establishes an intriguing connection between extreme value statistics and
traveling wave propagation in the context of the fragmentation problem.

</DOC>
<DOC>
<DOCNO> 151874 </DOCNO>
Superstrings on AdS_3 and Symmetric Products


  Some properties of N=2 superstrings on AdS_3 x N are studied. Their spectrum
has the same pattern as 2-d CFTs in the moduli space of symmetric products
M^p/S_p, where p is associated with the number of long fundamental strings
required to construct the AdS_3 background, and M is the spacetime CFT
corresponding to short string excitations of a single long string. Worldsheet
operators associated with w long strings correspond to twisted sectors of
M^p/S_p.

</DOC>
<DOC>
<DOCNO> 11877 </DOCNO>
Electronic Structure of Sr_2FeMoO_6


  We have analysed the unusual electronic structure of Sr_2FeMoO_6 combining
ab-initio and model Hamiltonian approaches. Our results indicate that there are
strong enhancements of the intraatomic exchange strength at the Mo site as well
as the antiferromagnetic coupling strength between Fe and Mo sites. We discuss
the possibility of a negative effective Coulomb correlation strength (U_{eff})
at the Mo site due to these renormalised interaction strengths.

</DOC>
<DOC>
<DOCNO> 121461 </DOCNO>
VLBI imaging of the gravitational lens MGJ0414+0534


  We observed the quadruple gravitationally lensed image of MGJ0414+0534 on 23
November 1997 with a global VLBI array at 8.4 GHz. We report wide-field imaging
results of its four components at submilliarcsecond resolution, displaying
complex core-like and jet-like extended structures. A simple model combining a
singular isothermal ellipsoid to represent the main lens galaxy, external
shear, and a singular isothermal sphere to represent an additional, nearby
object accounts well for the core positions and flux densities of the VLBI
images. This model predicts delays between the different lensed images of
several weeks.

</DOC>
<DOC>
<DOCNO> 179045 </DOCNO>
Particle-Rotor Model Description of Doubly Odd Ta Isotopes


  The doubly odd Ta isotopes are studied within the framework of the
particle-rotor model. The main aim of this study is to obtain information on
the neutron-proton interaction in deformed nuclei, with particular attention
focused on the role of the tensor force. To this end, both zero-range abd
finite-range phenomenological interactions are considered. Comparison of the
calculated results with experimental data provides evidence of the importance
of the tensor-force effects. We have also performed calculations using a
realistic two-body G matrix for the neutron proton interaction. Some
preliminary results are presented here.

</DOC>
<DOC>
<DOCNO> 12094 </DOCNO>
Random walks with strongly inhomogeneous rates and singular diffusions:


  Let $\tau = (\tau_i : i \in {\Bbb Z})$ denote i.i.d.~positive random
variables with common distribution $F$ and (conditional on $\tau$) let $X =
  (X_t : t\geq0, X_0=0)$, be a continuous-time simple symmetric random walk on
${\Bbb Z}$ with inhomogeneous rates $(\tau_i^{-1} : i \in {\Bbb Z})$. When $F$
is in the domain of attraction of a stable law of exponent $\alpha<1$ (so that
${\Bbb E}(\tau_i) = \infty$ and X is subdiffusive), we prove that $(X,\tau)$,
suitably rescaled (in space and time), converges to a natural (singular)
diffusion $Z = (Z_t : t\geq0, Z_0=0)$ with a random (discrete) speed measure
$\rho$. The convergence is such that the ``amount of localization'', $\E
\sum_{i \in {\Bbb Z}} [\P(X_t = i|\tau)]^2$ converges as $t \to \infty$ to $\E
\sum_{z \in {\Bbb R}} [\P(Z_s = z|\rho)]^2 > 0$, which is independent of $s>0$
because of scaling/self-similarity properties of $(Z,\rho)$. The scaling
properties of $(Z,\rho)$ are also closely related to the ``aging'' of
$(X,\tau)$. Our main technical result is a general convergence criterion for
localization and aging functionals of diffusions/walks $Y^{(\epsilon)}$ with
(nonrandom) speed measures $\mu^{(\epsilon)} \to \mu$ (in a sufficiently strong
sense).

</DOC>
<DOC>
<DOCNO> 119413 </DOCNO>
Gravitational Waves from Mesoscopic Dynamics of the Extra Dimensions


  Recent models which describe our world as a brane embedded in a higher
dimensional space introduce new geometrical degrees of freedom: the shape
and/or size of the extra dimensions, and the position of the brane. These modes
can be coherently excited by symmetry breaking in the early universe even on
``mesoscopic'' scales as large as 1 mm, leading to detectable gravitational
radiation. Two sources are described: relativistic turbulence caused by a
first-order transition of a radion potential, and Kibble excitation of
Nambu-Goldstone modes of brane displacement. Characteristic scales and spectral
properties are estimated and the prospects for observation by LISA are
discussed. Extra dimensions with scale between 10 \AA and 1 mm, which enter the
3+1-D era at cosmic temperatures between 1 and 1000 TeV, produce backgrounds
with energy peaked at observed frequencies in the LISA band, between $10^{-1}$
and $10^{-4}$ Hz. The background is detectable above instrument and
astrophysical foregrounds if initial metric perturbations are excited to a
fractional amplitude of $10^{-3}$ or more, a likely outcome for the
Nambu-Goldstone excitations.

</DOC>
<DOC>
<DOCNO> 8202 </DOCNO>
Snake orbits and related magnetic edge states


  We study the electron motion near magnetic field steps at which the strength
and/or sign of the magnetic field changes. The energy spectrum for such systems
is found and the electron states (bound and scattered) are compared with their
corresponding classical paths. Several classical properties as the velocity
parallel to the edge, the oscillation frequency perpendicular to the edge and
the extent of the states are compared with their quantum mechanical
counterpart. A class of magnetic edge states is found which do not have a
classical counterpart.

</DOC>
<DOC>
<DOCNO> 123329 </DOCNO>
Protoneutron stars and constraints on maximum and minimum mass of


  Constraints on minimum and maximum mass of ordinary neutron stars are imposed
by the consideration of their early evolution (protoneutron star stage).
Calculations are performed for a realistic standard model of hot, dense matter
(Lattimer & Swesty 1991) valid for both supranuclear and subnuclear densities.
Various assumptions concerning protoneutron star interior (large trapped lepton
number, no trapped lepton number, isentropic, isothermal) are taken into
account.

</DOC>
<DOC>
<DOCNO> 84733 </DOCNO>
Limits of crystallographic methods for detecting space topology


  We investigate to what extent the cosmic crystallographic methods aimed to
detect the topology of the universe using catalogues of cosmic objects would be
damaged by various observational uncertainties. We find that the topological
signature is robust in the case of Euclidean spaces, but is very fragile in the
case of compact hyperbolic spaces. Comparing our results to the presently
accepted range of values for the curvature parameters, the best hopes for
detecting space topology rest on elliptical space models.

</DOC>
<DOC>
<DOCNO> 120971 </DOCNO>
NGC1614: A Laboratory for Starburst Evolution


  The modest extinction and reasonably face-on viewing geometry make the
luminous IR galaxy NGC1614 an ideal laboratory for study of a powerful
starburst. HST/NICMOS observations show: 1.) deep CO stellar absorption,
tracing a starburst nucleus about 45 pc in diameter; 2.) surrounded by a ~600
pc diameter ring of supergiant HII regions revealed in Pa$\alpha$ line
emission; 3.) lying within a molecular ring indicated by its extinction shadow
in H-K; 4.) all at the center of a disturbed spiral galaxy. The luminosities of
the giant HII regions in the ring are extremely high, an order of magnitude
brighter than 30 Doradus. The relation of deep stellar CO bands to surrounding
ionized gas ring to molecular gas indicates that the luminous starburst started
in the nucleus and is propagating outward into the surrounding molecular ring.
This hypothesis is supported by evolutionary starburst modeling that shows that
the properties of NGC1614 can be fitted with two short-lived bursts of star
formation separated by 5 Myr. The total dynamical mass of the starburst region
of 1.3x10^9 Msol is mostly accounted for by the old pre-star burst stellar
population. Although our starburst models use a modified Salpeter IMF, the
tight mass budget suggests that the IMF may contain relatively more 10-30 Msol
stars and fewer low mass stars than the Salpeter function. The dynamical mass
is nearly 4 times smaller than the mass of molecular gas estimated from the
standard ratio of 12CO(1-0) to H2. A number of arguments place the mass of gas
in the starburst region at ~25% of the dynamical mass, nominally about 1/15 and
with an upper limit of 1/10 of the amount estimated from 12CO and the standard
ratio. (Abridged)

</DOC>
<DOC>
<DOCNO> 152549 </DOCNO>
The Heavy Dirac Monopole


  We present a model for the Dirac magnetic monopole, suitable for the strong
coupling regime. The magnetic monopole is static, has charge g and mass M,
occupying a volume of radius R ~ O (g^2/M). It is shown that inside each
n-monopole there exist infinite multipoles. It is given an analytical proof of
the existence of monopole-antimonopole bound state. Theses bound-states might
give additional strong light to light scattering in the proton-antiproton
collision process at FermiLab TEVATRON.

</DOC>
<DOC>
<DOCNO> 150847 </DOCNO>
Integration of the SL(2,R)/U(1) Gauged WZNW Theory by Reduction and


  Using a gauge invariant reduction we directly integrate the SL(2,R)/U(1) WZNW
theory. We prove that the conserved parafermions of this theory are coset
currents. Quantum mechanically, the parafermion algebra, the energy-momentum
tensor, and `auxiliary' parafermions are deformed in a self-consistent manner.

</DOC>
<DOC>
<DOCNO> 99320 </DOCNO>
Numerical Investigation of a Dipole Type Solution for Unsteady


  A model of unsteady filtration (seepage) in a porous medium with capillary
retention is considered. It leads to a free boundary problem for a generalized
porous medium equation where the location of the boundary of the water mound is
determined as part of the solution. The numerical solution of the free boundary
problem is shown to possess self-similar intermediate asymptotics. On the other
hand, the asymptotic solution can be obtained from a non-linear boundary value
problem. Numerical solution of the resulting eigenvalue problem agrees with the
solution of the partial differential equation for intermediate times. In the
second part of the work, we consider the problem of control of the water mound
extension by a forced drainage.

</DOC>
<DOC>
<DOCNO> 100586 </DOCNO>
On Lepowsky-Wilson's Z-algebra


  We show that the deformed Virasoro algebra specializes in a certain limit to
Lepowsky-Wilson's Z-algebra. This leads to a free field realization of the
affine Lie algebra \hat{sl_2} which respects the principal gradation. We
discuss some features of this bosonization including the screening current and
vertex operators.

</DOC>
<DOC>
<DOCNO> 68912 </DOCNO>
Q-ball formation in the MSSM with explicit CP violation


  Q-balls generically exist in the supersymmetric extensions of the standard
model. Taking into account the additional sources of CP violation, which are
naturally accomodated by the supersymmetric models, it is shown that the Q-ball
matter depends additively on individual CP phases, whereas mass per unit charge
in the Q-ball depends only on the relative phases. There are regions of the
parameter space where there is no stable Q-ball solution in the CP-conserving
limit whereas finite CP phases induce a stable Q-ball.

</DOC>
<DOC>
<DOCNO> 169925 </DOCNO>
A Quantum Approach To Static Games Of Complete Information


  We extend the concept of a classical two-person static game to the quantum
domain, by giving an Hilbert structure to the space of classical strategies and
studying the Battle of the Sexes game. We show that the introduction of
entangled strategies leads to a unique solution of this game.

</DOC>
<DOC>
<DOCNO> 150454 </DOCNO>
Schwarzschild black hole in the dilatonic domain wall


  In the dilatonic domain wall model, we study the Schwarzschild black hole as
a solution to the Kaluza-Klein (KK) zero mode effective action which is
equivalent to the Brans-Dicke (BD) model with a potential. This can describe
the large Randall-Sundrum (RS) black hole whose horizon is to be the
intersection of the black cigar with the brane.
  The black cigar located far from the AdS$_5$-horizon is known to be stable,
but any explicit calculation for stability of the RS black hole at $z=0$ is not
yet performed. Here its stability is investigated against the $z$-independent
perturbations composed of odd, even parities of graviton ($h_{\mu\nu}$) and BD
scalar($h_{44} = 2\phi $). It seems that the RS black hole is classically
unstable because it has a potential instability at wavelength with $\lambda >
1/(2k)$. However, this is not allowed inside an AdS$_5$-box of the size with
$1/(2k)$. Thus the RS black hole becomes stable. The RS black hole can be
considered as a stable remnant at $z=0 $ of the black cigar.

</DOC>
<DOC>
<DOCNO> 12412 </DOCNO>
Correlations and fluctuations of a confined electron gas


  The grand potential $\Omega$ and the response $R = - \partial \Omega
/\partial x$ of a phase-coherent confined noninteracting electron gas depend
sensitively on chemical potential $\mu$ or external parameter $x$. We compute
their autocorrelation as a function of $\mu$, $x$ and temperature. The result
is related to the short-time dynamics of the corresponding classical system,
implying in general the absence of a universal regime. Chaotic, diffusive and
integrable motions are investigated, and illustrated numerically. The
autocorrelation of the persistent current of a disordered mesoscopic ring is
also computed.

</DOC>
<DOC>
<DOCNO> 151171 </DOCNO>
Numerical Analysis of the Double Scaling Limit in the IIB Matrix Model


  The bosonic IIB matrix model is studied using a numerical method. This model
contains the bosonic part of the IIB matrix model conjectured to be a
non-perturbative definition of the type IIB superstring theory. The large N
scaling behavior of the model is shown performing a Monte Carlo simulation. The
expectation value of the Wilson loop operator is measured and the string
tension is estimated. The numerical results show the prescription of the double
scaling limit.

</DOC>
<DOC>
<DOCNO> 102575 </DOCNO>
A remarkable periodic solution of the three-body problem in the case of


  Using a variational method, we exhibit a surprisingly simple periodic orbit
for the newtonian problem of three equal masses in the plane. The orbit has
zero angular momentum and a very rich symmetry pattern. Its most surprising
feature is that the three bodies chase each other around a fixed eight-shaped
curve. Setting aside collinear motions, the only other known motion along a
fixed curve in the inertial plane is the ``Lagrange relative equilibrium" in
which the three bodies form a rigid equilateral triangle which rotates at
constant angular velocity within its circumscribing circle. Our orbit visits
in turns every ``Euler configuration" in which one of the bodies sits at the
midpoint of the segment defined by the other two (Figure 1). Numerical
computations by Carles Sim\'o, to be published elsewhere, indicate that the
orbit is ``stable" (i.e. completely elliptic with torsion). Moreover, they
show that the moment of inertia I(t) with respect to the center of mass and
the potential U(t) as functions of time are almost constant.

</DOC>
<DOC>
<DOCNO> 121934 </DOCNO>
The Effects of Noise and Sampling on the Spectral Correlation Function


  The effects of noise and sampling on the ``Spectral Correlation Function''
(SCF) introduced by Rosolowsky et al. 1999 are studied using observational
data, numerical simulations of magneto-hydrodynamic turbulence, and simple
models of Gaussian spectral line profiles. The most significant innovations of
this paper are: i) the normalization of the SCF based on an analytic model for
the effect of noise; ii) the computation of the SCF as a function of the
spatial lag between spectra within a map. By computing of the dependence of the
SCF on the spatial lag, S_o(dr), we have been able to conclude that: 1) S_o(dr)
is a power law, with slope in the range of scales l_i-l_o. 2) The correlation
outer scale, l_o, is determined by the size of the map, and no evidence for a
true departure from self-similarity on large scales has been found. 3) The
correlation inner scale, l_i, is a true estimate of the smallest self-similar
scale in a map. 4) The spectral slope in a given region, is independent of
velocity resolution (above a minimum resolution threshold), spatial resolution,
and average spectrum quality. 5) Molecular transitions which trace higher gas
density yield larger values of the spectral slope than transitions tracing
lower gas density. 6) Nyquist sampling, bad pixels in detector arrays, and
reference sharing data acquisition need to be taken into account for a correct
determination of the SCF at lag dr=1. The value of the spectral slope, however,
can be computed correctly without a detailed knowledge of observational
procedures.

</DOC>
<DOC>
<DOCNO> 85434 </DOCNO>
Weyl's spaces with shear-free and expansion-free conformal Killing


  Conditions for the existence of shear-free and expansion-free non-null vector
fields in spaces with affine connections and metrics are found. On their basis
Weyl's spaces with shear-free and expansion-free conformal Killing vectors are
considered. The necessary and sufficient conditions are found under which a
free spinless test particle could move in spaces with affine connections and
metrics on a curve described by means of an auto-parallel equation. In Weyl's
spaces with Weyl's covector, constructed by the use of a dilaton field, the
dilaton field appears as a scaling factor for the rest mass density of the test
particle.
  PACS numbers: 02.40.Ky, 04.20.Cv, 04.50.+h, 04.90.+e

</DOC>
<DOC>
<DOCNO> 120890 </DOCNO>
The Dynamics of the Formation of Degenerate Heavy Neutrino Stars


  Through reformulating the cold, self-gravitating fermion gas as a Bose
condensate by identifying their mutual Thomas-Fermi limits, the dissipationless
formation of a heavy neutrino star in gravitational collapse is numerically
demonstrated. Such stars offer an alternative to supermassive black holes for
the compact dark objects at the centers of galaxies.

</DOC>
<DOC>
<DOCNO> 118883 </DOCNO>
Local Luminosity Function at 15$\mu m$ and Galaxy Evolution Seen by


  A local luminosity function at 15$\mu m$ is derived using the bivariate
(15$\mu m$ vs. 60$\mu m$ luminosity) method, based on the newly published
ISOCAM LW3-band (15$\mu m$) survey of the very deep IRAS 60$\mu m$ sample in
the north ecliptic pole region (NEPR). New IRAS 60$\mu m$ fluxes are obtained
using the SCANPI/SUPERSCANPI software at the new ISOCAM positions of the
sources in the sample. It is found to be in excellent agreement with the 15$\mu
m$ local luminosity function published by Xu et al (1998), which is derived
from the {\it predicted} 15$\mu m$ luminosities of a sample of IRAS 25$\mu m$
selected galaxies. Model predictions of number counts and redshift
distributions based on the local luminosity function and assumptions of its
evolution with the redshift are calculated and compared with the data of ISOCAM
15$\mu m$ surveys. Strong luminosity evolution on the order of $L\propto
(1+z)^{4.5}$ is suggested in these comparisons, while pure density evolution
can be ruled out with high confidence. The sharp peak at about 0.4mJy in the
Euclidean normalized differential counts at 15$\mu m$ can be explained by the
effects of MIR broadband emission features, eliminating the need for any
hypothesis for a 'new population'. It is found that the contribution from the
population represented by ISOCAM 15$\mu m$ sources can account for the entire
IR/submm background, leaving little room for any missing 'new population' which
can be significant energy sources of the IR/submm sky.

</DOC>
<DOC>
<DOCNO> 152388 </DOCNO>
The Translation Groups as Generators of Gauge Transformation in


  The translation group T(2), contained in Wigner's little group for massless
particles, is shown to generate gauge transformations in the Kalb-Ramond
theory, exactly as happens in Maxwell case. For the topologically massive
($B\wedge$F) gauge theory, both T(2) and T(3), act as the corresponding
generators.

</DOC>
<DOC>
<DOCNO> 67706 </DOCNO>
Quark phases in neutron stars and a "third family" of compact stars as a


  The appearance of quark phases in the dense interior of neutron stars
provides one possibility to soften the equation of state (EOS) of neutron star
matter at high densities. This softening leads to more compact equilibrium
configurations of neutron stars compared to pure hadronic stars of the same
mass. We investigate the question to which amount the compactness of a neutron
star can be attributed to the presence of a quark phase. For this purpose we
employ several hadronic EOS in the framework of the relativistic mean-field
(RMF) model and an extended MIT bag model to describe the quark phase. We find
that - almost independent of the model parameters - the radius of a pure
hadronic neutron star gets typically reduced by 20-30% if a pure quark phase in
the center of the star does exist. For some EOS we furthermore find the
possibility of a "third family" of compact stars which may exist besides the
two known families of white dwarfs and neutron stars. We show how an
experimental proof of the existence of a third family by mass and radius
measurements may provide a unique signature for a phase transition inside
neutron stars.

</DOC>
<DOC>
<DOCNO> 100880 </DOCNO>
Realization of the Three-dimensional Quantum Euclidean Space by


  The three-dimensional quantum Euclidean space is an example of a
non-commutative space that is obtained from Euclidean space by $q$-deformation.
Simultaneously, angular momentum is deformed to $so_q(3)$, it acts on the
$q$-Euclidean space that becomes a $so_q(3)$-module algebra this way. In this
paper it is shown, that this algebra can be realized by differential operators
acting on $C^{\infty}$ functions on $\mathbb{R}^3$. On a factorspace of
$C^{\infty}(\mathbb{R}^3)$ a scalar product can be defined that leads to a
Hilbert space, such that the action of the differential operators is defined on
a dense set in this Hilbert space and algebraically self-adjoint becomes
self-adjoint for the linear operator in the Hilbert space. The self-adjoint
coordinates have discrete eigenvalues, the spectrum can be considered as a
$q$-lattice.

</DOC>
<DOC>
<DOCNO> 151556 </DOCNO>
O(d,d)-invariant collapse/inflation from colliding superstring waves


  Generalizing previous work, we study the collision of massless superstring
plane waves in D space-time dimensions within an explicitly
O(D-2,D-2)-invariant set of field equations. We discuss some general properties
of the solutions, showing in particular that they always lead to the formation
of a singularity in the future. Using the above symmetry, we obtain entire
classes of new analytic solutions with non-trivial metric, dilaton and
antisymmetric field, and discuss some of their properties of specific relevance
to string cosmology.

</DOC>
<DOC>
<DOCNO> 11281 </DOCNO>
Overcritical Rotation of a Trapped Bose-Einstein Condensate


  The rotational motion of an interacting Bose-Einstein condensate confined by
a harmonic trap is investigated by solving the hydrodynamic equations of
superfluids, with the irrotationality constraint for the velocity field. We
point out the occurrence of an overcritical branch where the system can rotate
with angular velocity larger than the oscillator frequencies. We show that in
the case of isotropic trapping the system exhibits a bifurcation from an
axisymmetric to a triaxial configuration, as a consequence of the interatomic
forces. The dynamical stability of the rotational motion with respect to the
dipole and quadrupole oscillations is explicitly discussed.

</DOC>
<DOC>
<DOCNO> 70287 </DOCNO>
New Physics Beyond the Standard Model at $\gamma \gamma$ Colliders


  The complementarity of $e^+e^-$ and $\gamma \gamma$ colliders to discover and
explore new physics beyond the Standard Model(SM) is discussed. After briefly
surveying a number of various new physics scenarios we concentrate in detail on
signatures for Large Extra Dimensions via the process $\gamma \gamma \to WW$.

</DOC>
<DOC>
<DOCNO> 151011 </DOCNO>
Spectral Universality of Real Chiral Random Matrix Ensembles


  We investigate the universality of microscopic eigenvalue correlations for
Random Matrix Theories with the global symmetries of the QCD partition
function. In this article we analyze the case of real valued chiral Random
Matrix Theories ($\beta =1$) by relating the kernel of the correlations
functions for $\beta =1$ to the kernel of chiral Random Matrix Theories with
complex matrix elements ($\beta = 2$), which is already known to be universal.
Our proof is based on a novel asymptotic property of the skew-orthogonal
polynomials: an integral over the corresponding wavefunctions oscillates about
half its asymptotic value in the region of the bulk of the zeros. This result
solves the puzzle that microscopic universality persists in spite of
contributions to the microscopic correlators from the region near the largest
zero of the skew-orthogonal polynomials. Our analytical results are illustrated
by the numerical construction of the skew-orthogonal polynomials for an $x^4$
probability potential.

</DOC>
<DOC>
<DOCNO> 178858 </DOCNO>
Deuteron Compton scattering and electromagnetic polarizabilities of the


  Differential cross section of deuteron Compton scattering has been calculated
using the Bonn NN-potential, a consistent set of meson-exchange currents and
seagulls, and lowest- and higher-order electromagnetic polarizabilities of the
nucleon. Estimates of the polarizabilities of the neutron are obtained from
recent experimental data.

</DOC>
<DOC>
<DOCNO> 99971 </DOCNO>
NNR Revisited


  We are interested in proving that if we use CS iterations of forcing notions
not adding reals and additional conditions then the limit forcing does not add
reals. As a result we prove that we can amalgamate two earlier methods and so
can prove the consistency with ZFC + G.C.H. of two statements gotten separately
earlier: SH and non-club guessing. We also prove the consistency of further
cases of ``non-club guessing''.

</DOC>
<DOC>
<DOCNO> 121548 </DOCNO>
NVO and the LSB Universe


  There is tremendous scientific potential in a National Virtual Observatory,
particularly for projects that need to mine large databases for rare or unusual
objects. However, the NVO will also make an impact on any project, large or
small, the requires a mixture of datasets to explore a wide range of
astrophysical phenomenon. In this article I discuss the influence of the NVO on
research into the formation and evolution of low surface brightness (LSB)
galaxies. In particular, I present the preliminary results from an NVO-style
project that combines the DPOSS and 2MASS datasets to search for giant disk
galaxies.

</DOC>
<DOC>
<DOCNO> 67730 </DOCNO>
T-dependence of pseudoscalar and scalar correlations


  Inhomogeneous pseudoscalar and scalar Bethe-Salpeter equations solved using a
renormalisation-group-improved rainbow-ladder truncation exhibit bound state
poles below and above T_c, the critical temperature for chiral symmetry
restoration. Above T_c the bound state amplitudes are identical, as are the
positions and residues of the pseudoscalar and scalar poles in the vertices. In
the chiral limit the pi^0 -> gamma gamma coupling vanishes at T_c, as do f_pi,
m_sigma, g_{sigma pi pi}. For light current-quark masses the 2-pi decay channel
of the isoscalar-scalar meson remains open until very near T_c, and the widths
of the dominant pion decay modes remain significant in the vicinity of the
crossover.

</DOC>
<DOC>
<DOCNO> 69543 </DOCNO>
K0-anti-K0 mixing in the 1/Nc expansion


  We present the result for the invariant B_K factor of K0-anti-K0 mixing in
the chiral limit and to next-to-leading order in the 1/Nc expansion. We
explicitly demonstrate the cancellation of the renormalization scale and scheme
dependences between short- and long-distance contributions in the final
expression. Numerical estimates are then given, by taking into account
increasingly refined short- and long-distance constraints of the underlying QCD
Green's function which governs the B_K factor.

</DOC>
<DOC>
<DOCNO> 13024 </DOCNO>
Unusual behaviors in the transport properties of REFe$_{4}$P$_{12}$ (RE:


  We have investigated the resistivity ($\rho$), thermoelectric power (TEP) and
Hall coefficient ($R_{H}$) on high quality single crystals of
REFe$_{4}$P$_{12}$. TEP in CeFe$_{4}$P$_{12}$ is extremely large ($\sim$
0.5mV/K at 290K) with a peak of $\sim$ 0.75mV/K at around 65K. The Hall
mobility also shows a peak at $\sim$ 65K, suggesting carriers with heavy masses
developed at lower temperatures related with the f-hybridized band. Both Pr-
and Nd- systems exhibit an apparent increase of $\rho$ with decreasing
temperature far above their magnetic transition temperatures. In the same
temperature ranges, TEP exhibits unusually large absolute values of -50$\mu$V/K
for PrFe$_{4}$P$_{12}$ and -15$\mu$V/K for NdFe$_{4}$P$_{12}$, respectively.
For PrFe$_{4}$P$_{12}$, such anomalous transport properties suggest an unusual
ground state, possibly related with the Quadrupolar Kondo effect.

</DOC>
<DOC>
<DOCNO> 84973 </DOCNO>
Gravity as a Key Problem of the Millenium


  Gravitation as a fundamental interaction that governs all phenomena at large
and very small scales, but still not well understood at a quantum level, is a
missing cardinal link to unification of all physical interactions. Problems of
the absolute G measurements and its possible time and range variations are
reflections of the unification problem. Integrable multidimensional models of
gravitation and cosmology make up one of the proper approaches to study basic
issues and strong field objects, the Early Universe and black hole physics in
particular. The choice, nature, classification and precision of determination
of fundamental physical constants are described. The problem of their temporal
variations is also discussed, temporal and range variations of G in particular.
A need for further absolute measurements of G, its possible range and time
variations is pointed out. The novel multipurpose space project SEE, aimed for
measuring G and its stability in space and time 3-4 orders better than at
present, may answer many important questions posed by gravitation, cosmology
and unified theories.

</DOC>
<DOC>
<DOCNO> 119124 </DOCNO>
Multifrequency Observations of the Virgo Blazars 3C 273 and 3C 279 in


  We report first observational results of multifrequency campaigns on the
prominent Virgo blazars 3C 273 and 3C 279 which were carried out in January and
February 1999. Both blazars are detected from radio to gamma-ray energies. We
present the measured X- to gamma-ray spectra of both sources, and for 3C 279 we
compare the 1999 broad-band (radio to gamma-ray) spectrum to measured previous
ones.

</DOC>
<DOC>
<DOCNO> 11177 </DOCNO>
Diblock copolymer ordering induced by patterned surfaces


  We use a Ginzburg-Landau free energy functional to investigate diblock
copolymer morphologies when the copolymer melt interacts with one surface or is
confined between two chemically patterned surfaces. For temperatures above the
order-disorder transition a complete linear response description of the
copolymer melt is given, in terms of an arbitrary two-dimensional surface
pattern. The appearance of order in the direction parallel to the surface is
found as a result of the order in the perpendicular direction. Below the
order-disorder point and in a thin-film geometry, our procedure enables the
analytic calculation of distorted perpendicular and tilted lamellar phases in
the presence of uniform or modulated surface fields.

</DOC>
<DOC>
<DOCNO> 13860 </DOCNO>
Factors Responsible for the Stability and the Existence of a Clean


  We present a critical theoretical study of electronic properties of silicon
nanoclusters, in particular the roles played by symmetry, relaxation, and
hydrogen passivation on the the stability, the gap states and the energy gap of
the system using the order-N [O(N)] non-orthogonal tight-binding molecular
dynamics and the local analysis of electronic structure.

</DOC>
<DOC>
<DOCNO> 72330 </DOCNO>
Planck-scale quintessence and the physics of structure formation


  In a recent paper we considered the possibility of a scalar field providing
an explanation for the cosmic acceleration. Our model had the interesting
properties of attractor-like behavior and having its parameters of O(1) in
Planck units. Here we discuss the effect of the field on large scale structure
and CMB anisotropies. We show how some versions of our model inspired by
"brane" physics have novel features due to the fact that the scalar field has a
significant role over a wider range of redshifts than for typical "dark energy"
models. One of these features is the additional suppression of the formation of
large scale structure, as compared with cosmological constant models. In light
of the new pressures being placed on cosmological parameters (in particular
H_0) by CMB data, this added suppression allows our "brane" models to give
excellent fits to both CMB and large scale structure data.

</DOC>
<DOC>
<DOCNO> 170572 </DOCNO>
Image and Coherence Transfer in the Stimulated Down-conversion Process


  The intensity transverse profile of the light produced in the process of
stimulated down-conversion is derived. A quantum-mechanical treatment is used.
We show that the angular spectrum of the pump laser can be transferred to the
stimulated down-converted beam, so that images can also be transferred from the
pump to the down-converted beam. We also show that the transfer can occur from
the stimulating beam to the down-converted one. Finally, we study the process
of diffraction through an arbitrarily shaped screen. For the special case of a
double-slit, the interference pattern is explicitly obtained. The visibility
for the spontaneous emitted light is in accordance with the van Cittert -
Zernike theorem for incoherent light, while the visibility for the stimulated
emitted light is unity. The overall visibility is in accordance with previous
experimental results.

</DOC>
<DOC>
<DOCNO> 100858 </DOCNO>
Weighted Completion of Galois Groups and Galois Actions on the


  This is a revision of the paper that was previously entitled "Weighted
Completion of Galois Groups and Some Conjectures of Deligne". Fix a prime
number $\l$. We prove a conjecture stated by Ihara, which he attributes to
Deligne, about the action of the absolute Galois group on the pro-$\l$
completion of the fundamental group of the thrice punctured projective line.
Similar techniques are also used to prove part of a conjecture of Goncharov,
also about the action of the absolute Galois group on the fundamental group of
the thrice punctured projective line. The main technical tool is the weighted
completion of a profinite group with respect to a reductive representation (and
other appropriate data). This theory is developed in this paper.

</DOC>
<DOC>
<DOCNO> 151916 </DOCNO>
A Note on the Equivalence of Vafa's and Douglas's Picture of Discrete


  For a general nonabelian group action and an arbitrary genus worldsheet we
show that Vafa's old definition of discrete torsion coincides with Douglas's
D-brane definition of discrete torsion associated to projective
representations.

</DOC>
<DOC>
<DOCNO> 84655 </DOCNO>
Exact Solutions in Multidimensional Cosmology with Shear and Bulk


  Multidimensional cosmological model describing the evolution of a fluid with
shear and bulk viscosity in $n$ Ricci-flat spaces is investigated. The
barotropic equation of state for the density and the pressure in each space is
assumed. The second equation of state is chosen in the form when the bulk and
the shear viscosity coefficients are inversely proportional to the volume of
the Universe. The integrability of Einstein equations reads as a colinearity
constraint between vectors which are related to constant parameters in the
first and second equations of state. We give exact solutions in a Kasner-like
form. The processes of dynamical compactification and the entropy production
are discussed. The non-singular $D$-dimensional isotropic viscous solution is
singled out.

</DOC>
<DOC>
<DOCNO> 80881 </DOCNO>
Topologically non-trivial configurations in 3-dimensional Yang-Mills


  Recently Anishetty, Majumdar and Sharatchandra have proposed a way of
characterizing topologically non-trivial configurations for 2+1-dimensional
Yang-Mills theory in a local and manifestly gauge invariant manner. Here we
develop criteria to locate such objects in lattice gauge theory and find them
in numerical simulations.

</DOC>
<DOC>
<DOCNO> 150520 </DOCNO>
Self-Dual Model Coupled to Bosons


  In this paper we investigated the dynamics, at the quantum level, of the
self-dual field minimally coupled to bosons. In this investigation we use the
Dirac bracket quantization procedure to quantize the model. Also, the
relativistic invariance is tested in connection with the elastic boson-boson
scattering amplitudes.

</DOC>
<DOC>
<DOCNO> 67840 </DOCNO>
The Nambu-Goto action as the one of the quantized space-time excitation


  The concept of the quantized space-time of the formless finite fundamental
elements is suggested. This space-time can be defined as a set of continual
space-time coverings by simply connected non-overlapping regions of any form
and arbitrary sizes with some probability measure. The functional integrating
method and the space-time action problem are analyzed. A string in this
space-time is considered as an excitation of a number of fundamental elements
forming one-dimensional curve. It is possible to direct the way for the volume
term of the space-time action to yield the Nambu-Goto action with this
consideration.

</DOC>
<DOC>
<DOCNO> 11562 </DOCNO>
Decomposition of the Height Function of Scherk's First Surface


  We show that Scherk's first surface, a one-parameter family of solutions to
the minimal surface equation, may be written as a linear superposition of other
solutions with specific parametric values.

</DOC>
<DOC>
<DOCNO> 100093 </DOCNO>
Double point self-intersection surfaces of immersions


  A self-transverse immersion of a smooth manifold M^{k+2} in R^{2k+2} has a
double point self-intersection set which is the image of an immersion of a
smooth surface, the double point self-intersection surface. We prove that this
surface may have odd Euler characteristic if and only if k is congruent to 1
modulo 4 or k+1 is a power of 2. This corrects a previously published result
by Andras Szucs.
  The method of proof is to evaluate the Stiefel-Whitney numbers of the double
point self-intersection surface. By earier work of the authors these numbers
can be read off from the Hurewicz image h(\alpha ) in H_{2k+2}\Omega ^{\infty
}\Sigma ^{\infty }MO(k) of the element \alpha in \pi _{2k+2}\Omega ^{\infty
}\Sigma ^{\infty }MO(k) corresponding to the immersion under the
Pontrjagin-Thom construction.

</DOC>
<DOC>
<DOCNO> 8072 </DOCNO>
Mesoscopic proximity effect probed through superconducting contacts


  We investigate the properties of complex mesoscopic superconducting-normal
hybrid devices, Andreev-Interferometers in the case, where the current is
proped through a superconducting tunneling contact whereas the proximity effect
is generated by a transparent SN-interface. We show within the quasiclassical
Green's functions technique, how the fundamental SNIS-element of the such
structures can be mapped onto an effective S$^\prime$IS-junction, where
S$^\prime$ is the proximised material with an effective energy gap
$E_g<\Delta$. We propose the Andreev-Interferometer, where $E_g$ can be tuned
by an external phase $\phi$ and displays maxima at 0 mod $2\pi$ and minima at
$\pi$ mod $2\pi$. This leads to peculiar current-phase-relations We propose an
experiment to verify our predictions and show, how our results are consistent
with recent, unexplained experimental results.

</DOC>
<DOC>
<DOCNO> 174603 </DOCNO>
Charge symmetry breaking of the nucleon-nucleon interaction:


  We investigate three models for the charge symmetry breaking (CSB) of the
nucleon-nucleon ($NN$) interaction (based upon $\rho$-$\omega$ mixing, nucleon
mass splitting, and phenomenology) that all reproduce the empirical value for
the CSB of the $^1S_0$ scattering length ($\Delta a_{CSB}$) accurately. We
reveal that these models make very different predictions for CSB in $^3P_J$
waves and examine the impact of this on some observable quantities of $A\geq 3$
nuclear systems. It turns out that the $^3$H-$^3$He binding energy difference
is essentially ruled by $\Delta a_{CSB}$ and not very sensitive to CSB from $P$
waves. However, the Coulomb displacement energies (which are the subject of the
Nolen-Schiffer anomaly) receive about 50% of their CSB contribution from $NN$
partial waves beyond $^1S_0$. Consequently, the predictions by the various CSB
models differ here substantially (10-20%). Unfortunately, the evaluation of the
leading Coulomb contributions carry a large uncertainty such that no
discrimination between the competing CSB models can presently be made. To
decide the issue we suggest to look into nuclear few-body reactions that are
sensitive to CSB of the nuclear force.

</DOC>
<DOC>
<DOCNO> 11817 </DOCNO>
Crystalline Color Superconductivity


  In any context in which color superconductivity arises in nature, it is
likely to involve pairing between species of quarks with differing chemical
potentials. For suitable values of the differences between chemical potentials,
Cooper pairs with nonzero total momentum are favored, as was first realized by
Larkin, Ovchinnikov, Fulde and Ferrell (LOFF). Condensates of this sort
spontaneously break translational and rotational invariance, leading to gaps
which vary periodically in a crystalline pattern. Unlike the original LOFF
state, these crystalline quark matter condensates include both spin zero and
spin one Cooper pairs. We explore the range of parameters for which crystalline
color superconductivity arises in the QCD phase diagram. If in some shell
within the quark matter core of a neutron star (or within a strange quark star)
the quark number densities are such that crystalline color superconductivity
arises, rotational vortices may be pinned in this shell, making it a locus for
glitch phenomena.

</DOC>
<DOC>
<DOCNO> 102201 </DOCNO>
Presenting Schur algebras as quotients of the universal enveloping


  We give a presentation of Schur algebras (over the rational number field) by
generators and relations, in fact a presentation which is compatible with
Serre's presentation of the universal enveloping algebra of a simple Lie
algebra. In the process we find a new basis for Schur algebras, a truncated
form of the usual PBW basis. We also locate the integral Schur algebra within
the presented algebra as the analogue of Kostant's Z-form, and show that it has
an integral basis which is a truncated version of Kostant's basis.

</DOC>
<DOC>
<DOCNO> 121558 </DOCNO>
The `Second Parameter': A Memory from the Globular Cluster Formation


  We study the correlations between the distribution of stars on the horizontal
branch (HB), the HB morphology, with some other properties of globular clusters
(GCs) in a large sample of GCs. We strengthen previous results that a general
correlation exists only between HB morphology and metallicity. Correlations
with other properties, e.g., central density and core radius, exist only for
GCs within a narrow metallicity range. We conjecture that the lack of
correlations with present properties of GCs (besides metallicity), is because
the variation of the HB morphologies between GCs having similar metallicities
is caused by a process, or processes, whose effect was determined at the
formation time of GCs. This process (or processes) is historically termed the
`second parameter', metallicity being the `first parameter'. We then argue that
the `planet second parameter' model, where the presence of planets and to a
lesser degree brown dwarfs and low mass main sequence stars is the `second
parameter', fits this conjecture.

</DOC>
<DOC>
<DOCNO> 7736 </DOCNO>
The number of guards needed by a museum: A phase transition in vertex


  In this letter we study the NP-complete vertex cover problem on finite
connectivity random graphs. When the allowed size of the cover set is
decreased, a discontinuous transition in solvability and typical-case
complexity occurs. This transition is characterized by means of exact numerical
simulations as well as by analytical replica calculations. The replica
symmetric phase diagram is in excellent agreement with numerical findings up to
average connectivity $e$, where replica symmetry becomes locally unstable.

</DOC>
<DOC>
<DOCNO> 170600 </DOCNO>
Optical Transition and Momentum Transfer in Atomic Wave Packets


  It is shown that the population Rabi-floppings in a lossless two-level atom,
interacting with a monochromatic electromagnetic field, in general are
convergent in time. The well-known continuous floppings take place because the
restricted choosing of initial conditions, that is when the atom initially is
chosen on ground or excited level before the interaction, simultaneously having
a definite value of momentum there. The convergence of Rabi-floppings in atomic
wave-packet-states is a direct consequence of Doppler effect on optical
transition rates (Rabi-frequencies): it gradually leads to ''irregular''
chaotic-type distributions of momentum in ground and excited energy levels,
smearing the amplitudes of Rabi-floppings. Conjointly with Rabi-floppings, the
coherent accumulation of momentum on each internal energy level monotonically
diminishes too.

</DOC>
<DOC>
<DOCNO> 85494 </DOCNO>
A generalized Hamiltonian Constraint Operator in Loop Quantum Gravity


  We study a generalized version of the Hamiltonian constraint operator in
nonperturbative loop quantum gravity. The generalization is based on admitting
arbitrary irreducible SU(2) representations in the regularization of the
operator, in contrast to the original definition where only the fundamental
representation is taken. This leads to a quantization ambiguity and to a family
of operators with the same classical limit. We calculate the action of the
Euclidean part of the generalized Hamiltonian constraint on trivalent states,
using the graphical notation of Temperley-Lieb recoupling theory. We discuss
the relation between this generalization of the Hamiltonian constraint and
crossing symmetry.

</DOC>
<DOC>
<DOCNO> 10367 </DOCNO>
Root lattices and quasicrystals


  It is shown how root lattices and their reciprocals might serve as the right
pool for the construction of quasicrystalline structure models. All
non-periodic symmetries observed so far are covered in minimal embedding with
maximal symmetry.

</DOC>
<DOC>
<DOCNO> 116888 </DOCNO>
The quantum vacuum, fractal geometry, and the quest for a new theory of


  In this letter recent developments are shown in experimental and theoretical
physics which brings into question the validity of General Relativity. This
letter emphasizes the construction of a fractal 3+\phi^3 spacetime, in
N-dimensions in order to formalize a physical and consistent theory of `quantum
gravity.' It is then shown that a `quantum gravity' effect could arise by means
of the Strong Equivalence Principle. Which is made possible through a pressure
of the form -kappa(R^{ca}_{b}-{1\over 2}g^{c sigma}_{ab}R^c)=kappa T^{c
sigma}_{ab}. Where it is seen that nuclear pressures can be added to rethe
gravitational field equations by means of twistor spaces.

</DOC>
<DOC>
<DOCNO> 121166 </DOCNO>
Comparison of UHECR spectra from necklaces and vortons


  Cosmic rays of energy higher than 10^19 eV may be explained by topological
defects produced in the early stages of universe. Two suitable alternatives
are: necklaces formed by magnetic monopoles connected by strings, and vortons
which are loops stabilized by superconducting currents. The former are
uniformly distributed in the universe, may account for cosmic rays above the
ankle, suffer a transient GZK cutoff with a subsequent recovery and isotropy of
observations is expected. The latter are concentrated in the galactic halo,
require an additional extragalactic contribution between the ankle and the GZK
cutoff, beyond which give a harder component and predict anisotropy related to
mass concentration.

</DOC>
<DOC>
<DOCNO> 118757 </DOCNO>
Massive Stars in the Range $\rm 13-25 M_\odot$: Evolution and


  We present the evolutionary properties of a set of massive stellar models
(namely 13, 15, 20 and 25 $\rm M_\odot$) from the main sequence phase up to the
onset of the iron core collapse. All these models have initial solar chemical
composition, i.e. Y=0.285 and Z=0.02. A 179 isotope network, extending from
neutron up to $\rm ^{68}Zn$ and fully coupled to the evolutionary code has been
adopted from the Carbon burning onward. Our results are compared, whenever
possible, to similar computations available in literature.

</DOC>
<DOC>
<DOCNO> 7667 </DOCNO>
Condensation of a Hard-Core Bose Gas


  A grand canonical system of hard-core bosons, subject to thermal
fluctuations, is studied on a lattice. Starting from the slave-boson
representation with fields for occupied and unoccupied sites, an effective
field theory is derived in which a complex field corresponds with the order
parameter of the condensate and a real field with the total density of bosons.
Near the boundary between the normal and the superfluid phase we obtain the
Ginzburg-Landau functional for the superfluid order parameter. A mean-field
calculation shows that the critical temperature $T_c$ increases with increasing
density up to a maximum and decreases with further increasing density.

</DOC>
<DOC>
<DOCNO> 99396 </DOCNO>
Fermionic formulas for level-restricted generalized Kostka polynomials


  Level-restricted paths play an important role in crystal theory. They
correspond to certain highest weight vectors of modules of quantum affine
algebras. We show that the recently established bijection between
Littlewood--Richardson tableaux and rigged configurations is well-behaved with
respect to level-restriction and give an explicit characterization of
level-restricted rigged configurations. As a consequence a new general
fermionic formula for the level-restricted generalized Kostka polynomial is
obtained. Some coset branching functions of type $A$ are computed by taking
limits of these fermionic formulas.

</DOC>
<DOC>
<DOCNO> 152632 </DOCNO>
Testable scenario for Relativity with minimum-length


  I propose a general class of space-times whose structure is governed by
observer-independent scales of both velocity ($c$) and length (Planck length),
and I observe that these space-times can naturally host a modification of
FitzGerald-Lorentz contraction such that lengths which in their inertial rest
frame are bigger than a "minimum length" are also bigger than the minimum
length in all other inertial frames. With an analysis in leading order in the
minimum length, I show that this is the case in a specific illustrative example
of postulates for Relativity with velocity and length observer-independent
scales.

</DOC>
<DOC>
<DOCNO> 69780 </DOCNO>
A pot of gold at the end of the cosmic "raynbow"?


  We critically review the common belief that ultrahigh energy cosmic rays are
protons or atomic nuclei with masses not exceeding that of iron. We find that
heavier nuclei are indeed possible, and discuss possible sources and
acceleration mechanisms for such primaries. We also show detailed simulations
of extensive air showers produced by ``superheavy'' nuclei, and discuss
prospects for their detection in future experiments.

</DOC>
<DOC>
<DOCNO> 101788 </DOCNO>
Hyperelliptic jacobians and projective linear Galois groups


  In his previous paper (Math. Res. Letters 7(2000), 123--132) the author
proved that in characteristic zero the jacobian $J(C)$ of a hyperelliptic curve
$C: y^2=f(x)$ has only trivial endomorphisms over an algebraic closure $K_a$ of
the ground field $K$ if the Galois group $Gal(f)$ of the irreducible polynomial
$f(x) \in K[x]$ is either the symmetric group $S_n$ or the alternating group
$A_n$. Here $n>4$ is the degree of $f$.
 In math.AG/0003002 we extended this result to the case of certain ``smaller''
Galois groups. In particular, we treated the infinite series $n=2^r+1,
Gal(f)=L_2(2^r)$ and $n=2^{4r+2}+1, Gal(f)=Sz(2^{2r+1})$.
  In the present paper we prove that $J(C)$ has only trivial endomorphisms over
$K_a$ if the set of roots of $f$ could be identified with the
$(m-1)$-dimensional projective space $P^{m-1}(F_q)$ over a finite field $F_q$
of odd characteristic in such a way that $Gal(f)$, viewed as its permutation
group, becomes either the projective linear group $PGL(m,F_q)$ or the
projective special linear group $L_m(q):=PSL(m,F_q)$. Here we assume that
$m>2$.

</DOC>
<DOC>
<DOCNO> 116374 </DOCNO>
Light propagation control by finite-size effects in photonic crystals


  We exhibit the strong influence on light propagation of the finite size in
photonic band-gap material. We show that light emission can be controlled by
the symmetry group of the boundary of the finite device. These results lead
simply to important practical applications.

</DOC>
<DOC>
<DOCNO> 13648 </DOCNO>
Ground State of Strongly Correlated Fermions: Short-Range Order


  A new variational method is developed to calculate the ground state energy of
Fermi systems with strong short-range correlations. A trial wave function of
Gutzwiller's type contains additional variational parameters corresponding to
configurations of pairs of nearest-neighbor sites. To evaluate the ground state
energy, generalized Kikuchi's pseudo-ensemble method is used. The Hubbard model
at half band-filling is investigated. The ground state energy of the
paramagnetic phase is calculated for a chain, square and simple cubic lattices.
It is shown that the short-range order lowers drastically the ground state
energy of the Hubbard model at intermediate interaction strength. The
paramagnetic phase of the Kondo-Hubbard model ($S=1/2$ and $S=5/2$) at half
band-filling is investigated. The ground state energy, correlation functions
and effective mass are calculated for chain, square and simple cubic lattices.
A quantum phase transition was found for simple cubic lattice.

</DOC>
<DOC>
<DOCNO> 40132 </DOCNO>
Is the $\nu_\mu --> \nu_s$ oscillation solution to the atmospheric


  Recently the SuperKamiokande collaboration have claimed that their data
exclude the $\nu_\mu --> \nu_s$ solution to the atmospheric neutrino anomaly at
more than 99% C.L. We critically examine this claim.

</DOC>
<DOC>
<DOCNO> 7843 </DOCNO>
Exact Zeros of the Partition Function for a Continuum System with Double


  We calculate the exact zeros of the partition function for a continuum system
where the probability distribution for the order parameter is given by two
asymmetric Gaussian peaks. When the positions of the two peaks coincide, the
two separate loci of zeros which used to give first-order transition touch each
other, with density of zeros vanishing at the contact point on the positive
real axis. Instead of the second-order transition of Ehrenfast classification
as one might naively expect, one finds a critical behavior in this limit.

</DOC>
<DOC>
<DOCNO> 69770 </DOCNO>
Teeny, tiny Dirac neutrino masses: an unorthodox point of view


  There are now strong hints suggesting that neutrinos do have a mass after
all. If they do have a mass, it would have to be tiny. Why is it so? Is it
Dirac or Majorana? Can one build a model in which a teeny, tiny Dirac neutrino
mass arises in a natural way? Can one learn something else other than just
neutrino masses? What are the extra phenomenological consequences of such a
model? These are the questions that I will try to focus on in this talk.

</DOC>
<DOC>
<DOCNO> 40162 </DOCNO>
Measurement of the Bbar0 and B- Meson Lifetimes


  The lifetimes of the Bbar0 and B- mesons are measured using a sample of about
four million hadronic Z decays collected from 1991 to 1995 with the ALEPH
detector at LEP. The data sample has been recently reprocessed, achieving a
substantial improvement in the tracking performance. Semileptonic decays of
Bbar0 and b- mesons are partially reconstructed by identifying events
containing a lepton with an associated D*+ or D0 meson. The proper time of the
B meson is estimated from the measured decay length and the momentum of the
D-lepton system. A fit to the proper time of 1880 D*+l- and 2856 D0l-
candidates yields the following results: tauBbar0 = 1.518 +- 0.053 +- 0.034 ps,
tauB = 1.648 +- 0.049 +- 0.035 ps, tauB-/tauBbar0 = 1.085 +- 0.059 +- 0.018.

</DOC>
<DOC>
<DOCNO> 9890 </DOCNO>
Zero-temperature TAP equations for the Ghatak-Sherrington model


  The zero-temperature TAP equations for the spin-1 Ghatak-Sherrington model
are investigated. The spin-glass energy density (ground state) is determined as
a function of the anisotropy crystal field $D$ for a large number of spins.
This allows us to locate a first-order transition between the spin-glass and
paramagnetic phases within a good accuracy. The total number of solutions is
also determined as a function of $D$.

</DOC>
<DOC>
<DOCNO> 117264 </DOCNO>
On the Nature of the Energy Current in Many-Particle Systems


  We show that the definition of an energy current for non-relativistic systems
with action-at-a-distance is possible if the interaction respects Gausses law,
i.e. if it is Coulomb-like. The energy current can transport kinetic and mass
(excitation) energy but not potential energy.

</DOC>
<DOC>
<DOCNO> 8541 </DOCNO>
Thermodynamic stability of Fe/O solid solution at inner-core conditions


  We present a new technique which allows the fully {\em ab initio} calculation
of the chemical potential of a substitutional impurity in a high-temperature
crystal, including harmonic and anharmonic lattice vibrations. The technique
uses the combination of thermodynamic integration and reference models
developed recently for the {\em ab initio} calculation of the free energy of
liquids and anharmonic solids. We apply the technique to the case of the
substitutional oxygen impurity in h.c.p. iron under Earth's core conditions,
which earlier static {\em ab initio} calculations indicated to be
thermodynamically very unstable. Our results show that entropic effects arising
from the large vibrational amplitude of the oxygen impurity give a major
reduction of the oxygen chemical potential, so that oxygen dissolved in h.c.p.
iron may be stabilised at concentrations up a few mol % under core conditions.

</DOC>
<DOC>
<DOCNO> 70598 </DOCNO>
Inflationary preheating and primordial black holes


  Preheating after inflation may over-produce primordial black holes (PBH's) in
many regions of parameter space. As an example we study two-field models with a
massless self-interacting inflaton, taking into account second order field and
metric backreaction effects as spatial averages. We find that a complex quilt
of parameter regions above the Gaussian PBH over-production threshold emerges
due to the enhancement of curvature perturbations on all scales. It should be
possible to constrain realistic models of inflation through PBH over-production
although many issues, such as rescattering and non-Gaussianity, remain unsolved
or unexplored.

</DOC>
<DOC>
<DOCNO> 13549 </DOCNO>
Absence of a Slater Transition in The Two-Dimensional Hubbard Model


  We present well-controlled results on the metal to insulator transition (MIT)
within the paramagnetic solution of the dynamical cluster approximation (DCA)
in the two-dimensional Hubbard model at half-filling. In the strong coupling
regime, a local picture describes the properties of the model; there is a large
charge gap $\Delta \approx U$. In the weak-coupling regime, we find a symbiosis
of short-range antiferromagnetic correlations and moment formation cause a gap
to open at finite temperature as in one dimension. Hence, this excludes the
mechanism of the MIT proposed by Slater long ago.

</DOC>
<DOC>
<DOCNO> 40176 </DOCNO>
RFQD - a Decelerating Radio Frequency Quadrupole for the CERN Antiproton


  The RFQD is designed to decelerate antiprotons of momentum 100 MeV/c (kinetic
energy 5.33MeV)down to a kinetic energy variable between ~10 keV and 120 keV.
Inside the RFQ body, at ground potential, the rf structure of the four-rod type
is mounted on insulating supports. It can be biased between plus/minus 60 kV dc
to achieve the continuous adjustment of output energy required by the ASACUSA
experiment at the CERN Antiproton Decelerator AD. The different parts of the
system are described and the present status reported.

</DOC>
<DOC>
<DOCNO> 178388 </DOCNO>
Excitation functions of hadronic observables from SIS to RHIC energies


  We calculate excitation functions for various dynamical quantities as well as
experimental observables from SIS to RHIC energies within the HSD transport
approach which is based on string, quark, diquark ($q, \bar{q}, qq,
\bar{q}\bar{q}$) and hadronic degrees of freedom without including any explicit
phase transition to a quark-gluon plasma (QGP). It is argued that the failure
of this more 'conventional' approach in comparison to experimental data should
indicate the presence of a different phase which might be either attributed to
space-time regions of vanishing scalar quark condensate ($<q\bar{q}>$ = 0) or
to the presence of a QGP phase with strongly interacting partons. We study the
$K/\pi$ ratio, the low mass dilepton enhancement in the invariant mass regime
from 0.2 -- 1.2 GeV as well as charmonium suppression for central Au + Au
collisions as a function of the bombarding energy and present predictions for
these observables as well as hadron rapiditiy distributions at RHIC energies.
Whereas all observables studied within HSD show smooth increasing/decreasing
excitation functions, the experimental $K^+/\pi^+$ ratio indicates a maximum at
11 A$\cdot$GeV (or above) which is interpreted as a signature for a chirally
restored phase in the course of the reaction.

</DOC>
<DOC>
<DOCNO> 116357 </DOCNO>
Fidelity and information in the quantum teleportation of continuous


  Ideally, quantum teleportation should transfer a quantum state without
distortion and without providing any information about that state. However,
quantum teleportation of continuous electromagnetic field variables introduces
additional noise, limiting the fidelity of the quantum state transfer. In this
article, the operator describing the quantum state transfer is derived. The
transfer operator modifies the probability amplitudes of the quantum state in a
shifted photon number base by enhancing low photon numbers and suppressing high
photon numbers. This modification of the statistical weight corresponds to a
measurement of finite resolution performed on the original quantum state. The
limited fidelity of quantum teleportation is thus shown to be a direct
consequence of the information obtained in the measurement.

</DOC>
<DOC>
<DOCNO> 85616 </DOCNO>
Axisymmetric Modes of Rotating Relativistic Stars in the Cowling


  Axisymmetric pulsations of rotating neutron stars can be excited in several
scenarios, such as core-collapse, crust and core-quakes and binary mergers and
could become detectable either in gravitational waves or high-energy radiation.
Here, we present a comprehensive study of all low-order axisymmetric modes of
uniformly and rapidly rotating relativistic stars. Initial stationary
configurations are appropriately perturbed and are numerically evolved using an
axisymmetric, nonlinear relativistic hydrodynamics code, assuming
time-independence of the gravitational field (Cowling approximation). The
simulations are performed using a high-resolution shock-capturing
finite-difference scheme accurate enough to maintain the initial rotation law
for a large number of rotational periods, even for stars at the mass-shedding
limit. Through Fourier transforms of the time evolution of selected fluid
variables, we compute the frequencies of quasi-radial and non-radial modes with
spherical harmonic indices l=0,1,2 and 3, for a sequence of rotating stars from
the non-rotating limit to the mass-shedding limit. The frequencies of the
axisymmetric modes are affected significantly by rotation only when the
rotation rate exceeds about 50% of the maximum allowed. As expected, at large
rotation rates, apparent mode crossings between different modes appear. In
addition to the above modes, several axisymmetric inertial modes are also
excited in our numerical evolutions.

</DOC>
<DOC>
<DOCNO> 169930 </DOCNO>
Reversing quantum dynamics with near-optimal quantum and classical


  We consider the problem of reversing quantum dynamics, with the goal of
preserving an initial state's quantum entanglement or classical correlation
with a reference system. We exhibit an approximate reversal operation, adapted
to the initial density operator and the ``noise'' dynamics to be reversed. We
show that its error in preserving either quantum or classical information is no
more than twice that of the optimal reversal operation. Applications to quantum
algorithms and information transmission are discussed.

</DOC>
<DOC>
<DOCNO> 71230 </DOCNO>
Atomic parity violation in cesium and implications for the 3 - 3 - 1


  The parity violation in cesium atom is analysed in the framework of the
models based on the SU(3)_C X SU(3)_L X U(1)_N gauge group. It is shown that in
the minimal version, the main contribution to a deviation of weak charge \Delta
Q_W due to direct Z' exchange is negative. New data on parity violation in the
cesium atom seems not favour to the minimal version, while it gets a positive
value in the version with right-handed neutrinos. We obtain a bound on the $Z'$
mass at a range from 1.4 TeV to 2.6 TeV. The allowed regions for the
Z-Z'$mixing angle are also derived.

</DOC>
<DOC>
<DOCNO> 71428 </DOCNO>
The charmed and bottom meson spectrum from lattice NRQCD


  The mass spectrum of S and P-wave mesons containing a single heavy quark has
been computed using quenched lattice nonrelativistic QCD. Numerical results
have been obtained at first, second and third order in the heavy quark
expansion, so convergence can be discussed. The computed spectrum of charmed
and bottom mesons is compared to existing model calculations and experimental
data.

</DOC>
<DOC>
<DOCNO> 80874 </DOCNO>
Results on the Gluon Propagator in Lattice Covariant Gauges


  We illustrate preliminary results on the gluon propagator computed in generic
covariant lattice gauges in the quenched approximation with the Wilson action.
We have applied a recently proposed procedure to fix a generic covariant gauge
on the lattice. We make a comparison among results obtained at two different
values of the gauge parameter and in the standard Landau's gauge.

</DOC>
<DOC>
<DOCNO> 119905 </DOCNO>
Interferometric observation of the L483 molecular core


  We present the aperture synthesis imaging of C3H2 2_{12}-1_{01} and HCO+ 1-0
lines and of continuum emission at 3.4 mm toward the class 0 young stellar
object, IRAS 18148-0440 in the L483 molecular cloud. The continuum emission is
detected at the IRAS position at a level of 16 mJy, indicating a compact source
with a 0.13 solar mass. The C3H2 delineates an envelope near the IRAS position,
with a size of 3000 AU x 2000 AU in R.A. and Dec. directions, respectively. A
velocity gradient detected only along the axis of outflow can be explained in
terms of free-fall motion of the envelope. The HCO+ line wing extends up to the
velocity of +- 6 km s^{-1} relative to the systemic one, and the high velocity
material shows a symmetric bipolarity and extends over 2' or 0.1 pc along the
east-west direction. It is found that the outflow material is clumpy and the
opening angle is widest for the slowest moving component. The core component of
the HCO+ 1-0 line exhibits an anti-infall asymmetry not only in interferometric
but also in single dish observations. It is attributable to the slow isotropic
outward motion of gas between the flattened envelope and the collimated
outflow.

</DOC>
<DOC>
<DOCNO> 151033 </DOCNO>
Nonlinear sigma model and Yang-Mills theory through non-critical string


  We consider two-dimensional nonlinear sigma model from the viewpoint of the
holography, which has been applied to the study of the Yang-Mills theory, based
on the non-critical string theory. We can see the renormalization group flows
for both the nonlinear sigma model and the Yang-Mills theory at the same time,
and the two theories are intimately related through a kind of dual relation of
the coupling constants. We address the running behaviors of these coupling
constants and also the asymptotic freedom of the Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 13887 </DOCNO>
Coulomb blockade thermometry using a two-dimensional array of tunnel


  We have measured current-voltage characteristics of two-dimensional arrays of
small tunnel junctions at temperatures from 1.5 K to 4.2 K. This corresponds to
thermal energies larger than the charging energy. We show that 2D-arrays can be
used as primary thermometers in the same way as 1D-arrays, and even have some
advantages over 1D-arrays. We have carried out Monte Carlo simulations, which
agree with our experimental results.

</DOC>
<DOC>
<DOCNO> 68182 </DOCNO>
Precision measurements of IVB parameters and bounds on new physics


  The main purpose of this thesis is to discuss the impact of electroweak
precision measurements on the present knowledge of particle physics, both in
the framework of the Standard Model and of its most straightforward extensions.
In Chapter 1 we give a general overview of the electroweak sector of the SM and
of SUSY phenomenology. In Chapter 2 we deal with different definitions of the
electroweak mixing angle, with particular attention to the relation between the
phenomenological angle $\theta$ and the MS parameter $\hat\theta$. In Chapter 3
we use results found in the previous chapter to discuss in detail how both the
decoupling and the non-decoupling approach to the running of coupling constants
in the MS scheme produce the same numerical value of $m_{GUT}$, despite of the
different initial conditions. In Chapter 4 we derive simple analytical formulas
for the contribution of a chargino almost degenerate with the lightest
neutralino to electroweak observables, showing that in the case of wino
domination the study of oblique corrections allows a concrete improvement of
experimental bounds on chargino mass. Finally, in Chapter 5 we consider the
possibility of extra fermion generations, proving that they are strongly
disfavoured by the present experimental data if all particles are heavier that
Z-boson, while for the specific case of the extra neutrino around 50 GeV in
mass (still allowed by experimental data) the quality of the fit is not worse
than the SM.

</DOC>
<DOC>
<DOCNO> 116608 </DOCNO>
Accurate transition rates for the 5p - 5s transitions in Kr I


  Branching fractions were measured for electric dipole transitions from the 5p
upper levels to the 5s levels in neutral krypton atoms. The measurements were
made with a wall-stabilized electric arc and a 2m monochromator for the
spectral lines in the visible, and with a hollow cathode lamp and the NIST
2m-Fourier transform spectrometer for the lines in the near infrared. A
semi-empirical calculation, based on accurately known lifetimes for six upper
levels, was used to calculate lifetimes for which accurate measurements do not
exist. This resulted in a complete set of lifetimes for all 5p levels.
Branching fractions and lifetimes were used to calculate transition rates for
the 5p-5s transitions. The relative uncertainties of the transition rates range
from less than 1% for the strongest lines to about 10% for the weakest lines.
Our data also reveal that most of the previous measurements appear to have been
affected by opacity effects in the light sources.

</DOC>
<DOC>
<DOCNO> 117290 </DOCNO>
Generation of electromagnetic pulses from plasma channels induced by


  We present a model that elucidates the physics underlying the generation of
an electromagnetic pulse from a femtosecond laser induced plasma channel. The
radiation pressure force from the laser pulse spatially separates the ionized
electrons from the heavier ions and the induced dipole moment subsequently
oscillates at the plasma frequency and radiates an electromagnetic pulse.

</DOC>
<DOC>
<DOCNO> 9853 </DOCNO>
Superfluid analogies of cosmological phenomena


  Superfluid 3He-A gives example of how chirality, Weyl fermions, gauge fields
and gravity appear in low energy corner together with corresponding symmetries,
including Lorentz symmetry and local SU(N). This supports idea that quantum
field theory (Standard Model or GUT) is effective theory describing low-energy
phenomena. * Momentum space topology of fermionic vacuum provides topological
stability of universality class of systems, where above properties appear. *
BCS scheme for 3He-A incorporates both ``relativistic'' infrared regime and
ultraviolet ``transplanckian'' range: subtle issues of cut-off in quantum field
theory and anomalies can be resolved on physical grounds. This allows to
separate ``renormalizable'' terms in action, treated by effective theory, from
those obtained only in ``transPlanckian'' physics. * Energy density of
superfluid vacuum within effective theory is ~ E_{Planck}^4. Stability analysis
of ground state beyond effective theory leads to exact nullification of vacuum
energy: equilibrium vacuum is not gravitating. In nonequilibrium, vacuum energy
is of order energy density of matter. * 3He-A provides experimental prove for
anomalous nucleation of fermionic charge according to Adler-Bell-Jackiw. *
Helical instability in 3He-A is described by the same equations as formation of
magnetic field by right electrons in Joyce-Shaposhnikov scenario. * Macroscopic
parity violating effect and angular momentum paradox are both desribed by axial
gravitational Chern-Simons action. * High energy dispersion of quasiparticle
spectrum allow to treat problems of vacuum in presence of event horizon, etc.

</DOC>
<DOC>
<DOCNO> 119568 </DOCNO>
Redshift estimation from low-resolution prism SEDs with an NGST MOS


  We discuss the utility of a low resolution prism as a component of a
Multi-Object Spectrometer for NASA's proposed Next Generation Space Telescope
(NGST). Low resolution prism spectroscopy permits simultaneous observation of
the 0.6-5micron wavelength regime at R~50. To such data we can apply the modern
techniques in spectral energy distribution (SED) fitting to determine source
redshifts, sometimes called ``photometric redshifts''. Low resolution prism
observations of galaxy SED's provide a significant advantage over multi-filter
observations for any realistic observing strategy, and we have performed
extensive simulations to quantify it. The advantage of the prism is largest in
the regime of faint (K_AB>30) objects at high redshift (z>4), the primary
discovery space of NGST. Many important objects will be too faint for follow up
at higher spectral resolution, so prism observations are the optimal technique
to study them. Prism observations also reduce the contamination of high
redshift samples by lower redshift interlopers.

</DOC>
<DOC>
<DOCNO> 69735 </DOCNO>
Baryon Number Flow in High-Energy Collisions


  It is not obvious which partons in the proton carry its baryon number (BN).
We present arguments that BN is associated with a specific topology of gluonic
fields, rather than with the valence quarks. The BN distribution is easily
confused with the difference between the quark and antiquark distributions. We
argue, however, that they have quite different x-dependences. The distribution
of BN asymmetry distribution is nearly constant at small x while q(x)-\bar q(x)
\propto \sqrt{x}. This constancy of BN produces energy independence of the \bar
pp annihilation cross section at high energies. Recent measurement of the
baryon asymmetry at small x at HERA confirms this expectation. The BN asymmetry
at mid-rapidities in heavy ion collisions is substantially enhanced by multiple
interactions, as has been observed in recent experiments at the SPS. The same
gluonic mechanism of BN stopping increases the production rate for cascade
hyperons in a good accord with data. We expect nearly the same as at SPS amount
of BN stopped in higher energy collisions at RHIC and LHC, which is, however,
spread ove larger rapidity intervals.

</DOC>
<DOC>
<DOCNO> 9661 </DOCNO>
Absence of residual quasiparticle conductivity in the underdoped cuprate


  We report here measurements of the in-plane thermal conductivity K(T) of the
underdoped cuprate YBa2Cu4O8 (Y124) below 1K. K(T) is shown to follow a simple,
phononic T^3 dependence at the lowest temperatures for both current directions,
with a negligible linear, quasiparticle contribution. This observation is in
marked contrast with behavior reported in optimally doped cuprates, and implies
that extended zero-energy (or low energy) low-energy quasiparticles are absent
in YBa2Cu4O8 at low temperatures.

</DOC>
<DOC>
<DOCNO> 10948 </DOCNO>
Coherence Resonance in Chaotic Systems


  We show that it is possible for chaotic systems to display the main features
of coherence resonance. In particular, we show that a Chua model, operating in
a chaotic regime and in the presence of noise, can exhibit oscillations whose
regularity is optimal for some intermediate value of the noise intensity. We
find that the power spectrum of the signal develops a peak at finite frequency
at intermediate values of the noise. These are all signatures of coherence
resonance. We also experimentally study a Chua circuit and corroborate the
above simulation results. Finally, we analyze a simple model composed of two
separate limit cycles which still exhibits coherence resonance, and show that
its behavior is qualitatively similar to that of the chaotic Chua system

</DOC>
<DOC>
<DOCNO> 71116 </DOCNO>
Weak decays of Heavy mesons


  I explore the possibility of using heavy meson decays as probes for flavour
changing neutral transitions (FCNC) $c\to u\gamma$ and $c\to ul^+l^-$. In the
standard model, these are the most frequent FCN transitions among the quarks
with charge $2/3e_0$. I predict the short and long distance contributions to
the relevant heavy meson decays within the standard model and explore their
sensitivity to different scenarios of physics beyond the standard model. The
rare $B_c\to B_u^*\gamma$ decay is proposed as the most suitable case study of
the $c\to u\gamma$ transition and is studied with the ISGW model. Its detection
at the branching ratio much higher than $10^{-8}$ would signal new physics.
Weak decays of charm mesons to a light meson and a photon or a charged lepton
pair are also studied for this purpose. Their probabilities are found to be
dominated by the long distance contributions and raise our hopes that they may
be detected soon. A window of opportunity to probe the $c\to ul^+l^-$
transition is found in the decay $D\to \pi l^+l^-$, at the kinematical region
of high di-lepton mass. In order to study the charm meson decays, I adapt the
Heavy Meson Chiral Lagrangian approach and demonstrate for its applicability by
predicting the charm meson nonleptonic decay rates.

</DOC>
<DOC>
<DOCNO> 117376 </DOCNO>
Near infrared imaging spectroscopy of NGC1275


  We present H and K band imaging spectroscopy of the core regions of the
cD/AGN galaxy NGC1275. The spectra, including lines from H2, H, 12CO bandheads,
[FeII], and [FeIII], are exploited to constrain the star formation and
excitation mechanisms in the galaxy's nucleus. The near-infrared properties can
largely be accounted for by ionized gas in the NLR, dense molecular gas, and
hot dust concentrated near the active nucleus of NGC1275. The strong and
compact H2 emission is mostly from circumnuclear gas excited by the AGN and not
from the cooling flow. The extended emission of latetype stars is diluted in
the center by the thermal emission of hot dust.

</DOC>
<DOC>
<DOCNO> 152349 </DOCNO>
Supergravity couplings to Noncommutative Branes, Open Wilson Lines and


  Noncommutative gauge theories can be constructed from ordinary $U(\infty)$
gauge theories in lower dimensions. Using this construction we identify the
operators on noncommutative D-branes which couple to linearized supergravity
backgrounds, from a knowledge of such couplings to lower dimensional D-branes
with no $B$ field. These operators belong to a class of gauge invariant
observables involving open Wilson lines. Assuming a DBI form of the coupling we
show, to second order in the gauge potential but to all orders of the
noncommutativity parameter, that our proposal agrees with the operator obtained
in terms of ordinary gauge fields by considering brane actions in backgrounds
and then using the Seiberg-Witten map to rewrite this in terms of
noncommutative gauge fields. Our result clarify why a certain {\it commutative}
but {\it non-associative} ``generalized star product'' appears both in the
expansion of the open Wilson line, as well as in string amplitude computations
of open string - closed string couplings. We outline how our procedure can be
used to obtain operators in the noncommutative theory which are holographically
dual to supergravity modes.

</DOC>
<DOC>
<DOCNO> 8641 </DOCNO>
Evidence for a continuum limit in causal set dynamics


  We find evidence for a continuum limit of a particular causal set dynamics
which depends on only a single ``coupling constant'' $p$ and is easy to
simulate on a computer. The model in question is a stochastic process that can
also be interpreted as 1-dimensional directed percolation, or in terms of
random graphs.

</DOC>
<DOC>
<DOCNO> 85255 </DOCNO>
From Now to Timelike Infinity on a Finite Grid


  We use the conformal approach to numerical relativity to evolve hyperboloidal
gravitational wave data without any symmetry assumptions. Although our grid is
finite in space and time, we cover the whole future of the initial data in our
calculation, including future null and future timelike infinity.

</DOC>
<DOC>
<DOCNO> 67645 </DOCNO>
Light Stop: MSSM versus R-parity violation


  We discuss the phenomenology of the lightest stops in models where R-parity
is broken by bilinear terms. In this class of models we consider scenarios
where the R-parity breaking two-body decay stop_1 -> tau + b competes with the
leading three-body decays stop_1 -> W^+ + b + neutralino_1, H^+ + b +
neutralino_1, b slepton^+_i neutrino_l, b sneutrino_l l^+ (l=e, mu, tau). We
demonstrate that the R-parity violating decay can be the dominant one. In
particular we focus on the implications for a future electron posistion Linear
Collider.

</DOC>
<DOC>
<DOCNO> 178538 </DOCNO>
Effective chiral theory of kaon-nucleon scattering


  We apply the relativistic chiral SU(3) Lagrangian density to kaon-nucleon
scattering imposing constraints from the pion-nucleon s- and p-wave threshold
parameters at chiral order $Q^2$. The s and u channel decouplet baryon exchange
is included explicitly and is found to play a crucial role in understanding the
empirical s- and p-wave nuclear kaon dynamics quantitatively.

</DOC>
<DOC>
<DOCNO> 68921 </DOCNO>
Strangeness production from $\pi N$ collisions in nuclear matter


  Kaon production in pion-nucleon collisions in nuclear matter is studied in
the resonance model. To evaluate the in-medium modification of the reaction
amplitude as a function of the baryonic density we introduce relativistic,
mean-field potentials for the initial, final and intermediate mesonic and
baryonic states. These vector and scalar potentials were calculated using the
quark-meson coupling (QMC) model. The in-medium kaon production cross sections
in pion-nucleon interactions for reaction channels with $\Lambda$ and $\Sigma$
hyperons in the final state were calculated at the baryonic densities
appropriate to relativistic heavy ion collisions. Contrary to earlier work
which has not allowed for the change of the cross section in medium, we find
that the data for kaon production are consistent with a repulsive $K^+$-nucleus
potential.

</DOC>
<DOC>
<DOCNO> 69574 </DOCNO>
Leptogenesis from Neutralino Decay with Nonholomorphic R-Parity


  In supersymmetric models with lepton-number violation, hence also R-parity
violation, it is easy to have realistic neutrino masses, but then leptogenesis
becomes difficult to achieve. After explaining the general problems involved,
we study the details of a model which escapes these constraints and generates a
lepton asymmetry, which gets converted into the present observed baryon
asymmetry of the Universe through the electroweak sphalerons. This model
requires the presence of certain nonholomorphic R-parity violating terms. For
completeness we also present the most general R-parity violating Lagrangian
with soft nonholomorphic terms and study their consequences for the
charged-scalar mass matrix. New contributions to neutrino masses in this
scenario are discussed.

</DOC>
<DOC>
<DOCNO> 11416 </DOCNO>
Tail States in a Superconductor with Magnetic Impurities


  A field theoretic approach is developed to investigate the profile and
spectrum of sub-gap states in a superconductor subject to a weak magnetic
impurity potential. Such states are found to be associated with inhomogeneous
supersymmetry broken instanton configurations of the action.

</DOC>
<DOC>
<DOCNO> 84872 </DOCNO>
Black Hole Critical Phenomena Without Black Holes


  Studying the threshold of black hole formation via numerical evolution has
led to the discovery of fascinating nonlinear phenomena. Power-law mass
scaling, aspects of universality, and self-similarity have now been found for a
large variety of models. However, questions remain. Here I briefly review
critical phenomena, discuss some recent results, and describe a model which
demonstrates similar phenomena without gravity.

</DOC>
<DOC>
<DOCNO> 119679 </DOCNO>
Line formation in solar granulation: I. Fe line shapes, shifts and


  Realistic ab-initio 3D, radiative-hydrodynamical convection simulations of
the solar granulation have been applied to FeI and FeII line formation. In
contrast to classical analyses based on hydrostatic 1D model atmospheres the
procedure contains no adjustable free parameters but the treatment of the
numerical viscosity in the construction of the 3D, time-dependent,
inhomogeneous model atmosphere and the elemental abundance in the 3D spectral
synthesis. However, the numerical viscosity is introduced purely for numerical
stability purposes and is determined from standard hydrodynamical test cases
with no adjustments allowed to improve the agreement with the observational
constraints from the solar granulation. The non-thermal line broadening is
mainly provided by the Doppler shifts arising from the convective flows in the
solar photosphere and the solar oscillations. The almost perfect agreement
between the predicted temporally and spatially averaged line profiles for weak
Fe lines with the observed profiles and the absence of trends in derived
abundances with line strengths, seem to imply that the micro- and
macroturbulence concepts are obsolete in these 3D analyses. Furthermore, the
theoretical line asymmetries and shifts show a very satisfactory agreement with
observations with an accuracy of typically 50-100 m/s on an absolute velocity
scale. The remaining minor discrepancies point to how the convection
simulations can be refined further.

</DOC>
<DOC>
<DOCNO> 71246 </DOCNO>
Scalar fields at finite densities: A \delta expansion approach


  We use an optimized hopping parameter expansion (linear \delta expansion) for
the free energy to study the phase transitions at finite temperature and finite
charge density in a global U(1) scalar Higgs sector in the continuum and on the
lattice at large couplings. We are able to plot out phase diagrams in lattice
parameter space and find that the standard second-order phase transition with
temperature at zero chemical potential becomes first-order as the chemical
potential increases.

</DOC>
<DOC>
<DOCNO> 12965 </DOCNO>
Sensitive methods for estimating the anchoring strength of nematic


  The anchoring of the nematic liquid crystal
N-(p-methoxybenzylidene)-p-butylaniline (MBBA) on Langmuir-Blodgett monolayers
of fatty acids (COOHC$_{n}$H$_{2n+1}$) was studied as a function of the length
of the fatty acid alkyl chains, $n$ ($n = 15, 17, 19, 21$). The monolayers were
deposited onto ITO-coated glass plates which were used to assemble sandwich
cells of various thickness that were filled with MBBA in the nematic phase. The
mechanism of relaxation from the flow-induced quasi-planar to the
surface-induced homeotropic alignment was studied for the four decreases
linearly with increasing the length of the alkyl chains $n$ which suggests that
the Langmuir-Blodgett film plays a role in the phenomenon. This fact was
confirmed by a sensitive estimation of the anchoring strength of MBBA on the
fatty acid monolayers after anchoring breaking which takes place at the
transition between two electric-field--induced turbulent states, denoted as
DSM1 and DSM2. It was found that the threshold electric field for the anchoring
breaking, which can be considered as a measure of the anchoring strength, also
decreases linearly as $n$ increases. Both methods thus possess a high
sensitivity in resolving small differences in anchoring strength. In cells
coated with mixed Langmuir-Blodgett monolayers of two fatty acids ($n=15$ and
$n=17$) a maximum of the relaxation speed was observed when the two acids were
present in equal amount. This observation homeotropic cells by changing the
ratio between the components of the surfactant film.

</DOC>
<DOC>
<DOCNO> 102535 </DOCNO>
The stability radius of linear operator pencils


  Let T and S be two bounded linear operators from Banach spaces X into Y and
suppose that T is Fredholm and the stability number k(T;S) is 0. Let d(T;S) be
the supremum of all r > 0 such that dim N(T-\lambda S) and codim R(T-\lambda S)
are constant for all \lambda with |\lambda | < r. It was proved in 1980 by H.
Bart and D.C. Lay that d(T;S) = \lim_{n\to\infty}\gamma_{n}(T;S)^{1/n}, where
\gamma_{n}(T;S) are some non-negative (extended) real numbers. For X=Y and S =
I, the identity operator, we have \gamma_{n}(T;S) = \gamma (T^n), where \gamma
is the reduced minimum modulus. A different representation of the stability
radius is obtained here in terms of the spectral radii of generalized inverses
of T. The existence of generalized resolvents for Fredholm linear pencils is
also considered.

</DOC>
<DOC>
<DOCNO> 100822 </DOCNO>
Quantified propositional Goedel logics


  It is shown that G-up, the quantified propositional Goedel-Dummett logic
based on the truth-values set V-up = {1 - 1/n : n >= 1} u {1}, is decidable.
This result is obtained by reduction to Buechi's theory S1S. An alternative
proof based on elimination of quantifiers is also given, which yields both an
axiomatization and a characterization of G-up as the intersection of all
finite-valued quantified propositional Goedel logics.

</DOC>
<DOC>
<DOCNO> 72301 </DOCNO>
Three Active and Two Sterile Neutrinos in an E_6 Model of Diquark


  In the U(1)_N extension of the supersymmetric standard model with E_6
particle content, the heavy singlet superfield N may decay into a quark and a
diquark as well as an antiquark and an antidiquark, thus creating a baryon
asymmetry of the Universe. We show how the three doublet and two singlet
neutrinos in this model acquire mass from physics at the TeV scale without the
benefit of using N as a heavy right-handed neutrino. Specifically, the active
neutrinos get masses via the bilinear term \mu LX^c which conserves R-parity,
and via the nonzero masses of the sterile neutrinos. We predict fixed
properties of the extra Z' boson, as well as the new lepton doublets X and X^c,
and the observation of diquark resonances at hadron colliders in this scenario.

</DOC>
<DOC>
<DOCNO> 150965 </DOCNO>
3D reduction of the N-body Bethe-Salpeter equation


  We perform a 3D reduction of the two-fermion Bethe-Salpeter equation, by
series expansion around a positive-energy instantaneous approximation of the
Bethe-Salpeter kernel, followed by another series expansion at the 3D level in
order to get a manifestly hermitian 3D potential. It turns out that this
potential does not depend on the choice of the starting approximation of the
kernel anymore, and can be written in a very compact form. This result can also
be obtained directly by starting with an approximation of the free propagator,
based on integrals in the relative energies instead of the more usual
delta-constraint. Furthermore, the method can be generalized to a system of N
particles, consisting in any combination of bosons and fermions. As an example,
we write the 3D equation for systems of two or three fermions exchanging
photons, in Feynman or Coulomb's gauge.

</DOC>
<DOC>
<DOCNO> 118918 </DOCNO>
Pixel lensing towards M31 in principle and in practice


  The Andromeda galaxy (M31) provides a new line of sight for Galactic MACHO
studies and also a signature, near-far asymmetry, which may establish the
existence of MACHOs in the M31 halo. We outline the principles behind the
so-called ``pixel-lensing'' experiments monitoring unresolved stars in M31. We
present detailed simulations of the POINT-AGAPE survey now underway, which is
using the INT wide-field camera to map the microlensing distribution over a
substantial fraction of the M31 disc. We address the extent to which
pixel-lensing observables, which differ from those of classical microlensing,
can be used to determine the contribution and mass of M31 MACHOs. We also
present some preliminary light-curves obtained from the first season
(1999/2000) of INT data.

</DOC>
<DOC>
<DOCNO> 10746 </DOCNO>
Scaling Exponents in the Incommensurate Phase of the Sine-Gordon and


  In this paper we study the critical exponents of the quantum sine-Gordon and
U(1) Thirring models in the incommensurate phase. This phase appears when the
chemical potential $h$ exceeds a critical value and is characterized by a
finite density of solitons. The low-energy sector of this phase is critical and
is described by the Gaussian model (Tomonaga-Luttinger liquid) with the
compactification radius dependent on the soliton density and the sine-Gordon
model coupling constant $\beta$.
  For a fixed value of $\beta$, we find that the Luttinger parameter $K$ is
equal to 1/2 at the commensurate-incommensurate transition point and approaches
the asymptotic value $\beta^2/8\pi$ away from it. We describe a possible phase
diagram of the model consisting of an array of weakly coupled chains. The
possible phases are Fermi liquid, Spin Density Wave, Spin-Peierls and Wigner
crystal.

</DOC>
<DOC>
<DOCNO> 119844 </DOCNO>
A Comptonization Model for Phase Lag Variability in GRS 1915+105


  In this Letter we propose a simple thermal comptonization model to account
for the observed properties of the phase lags associated to the ``plateau''
intervals of GRS 1915+105. By invoking a temperature stratification in a corona
and assuming that the optical depth of the comptonizing region increases as the
disk inner radius moves inward, we are able to reproduce both the observed
colors and time lags in the continuum.

</DOC>
<DOC>
<DOCNO> 121971 </DOCNO>
XMM-Newton Detection of a Comptonized Accretion Disc in the Quasar


  We present XMM-Newton observations of the bright quasar PKS0558-504. The
0.2-10 keV spectrum is dominated by a large, variable soft X-ray excess. The
fastest flux variations imply accretion onto a Kerr black hole. The XMM-Newton
data suggest the presence of a `big blue bump' in PKS0558-504 extending from
the optical band to ~3 keV. The soft X-ray spectrum shows no evidence for
significant absorption or emission-line features. The most likely explanation
for the hot big blue bump is Comptonization by the multi-temperature corona of
a thermal accretion disc running at a high accretion rate.

</DOC>
<DOC>
<DOCNO> 119583 </DOCNO>
New type astrophysical solution to the solar neutrino problems and its


  The anomalously slow rotation of the solar core is just one from a remarkable
lists of fundamental indications showing that the solar core is somehow coupled
to the surface activity cycle. On the other hand, the atmospheric, LSND and
solar neutrino problems are not consistent, therefore one or more of the
neutrino experiments must be attributed - at least in part - to some phenomena
other than neutrino oscillations, or a fourth neutrino is required. We use the
luminosity constraint in a general case not considered yet, taking into account
nuclear reactions occurring in small hot bubbles indicated to be present in the
solar core (Grandpierre, 2000). The dynamic solar model fit the observed
neutrino fluxes within one-and-half sigma even without oscillations. This fit
is shown to be better than the present day MSW and VAC fits. An attracting
perspective is obtained for a simultaneous solution of the neutrino problems
and the solar core-related astrophysical problems. Predictions of the dynamic
solar model are presented for the SNO measurements.

</DOC>
<DOC>
<DOCNO> 119034 </DOCNO>
The Circumstellar Environment of the TTS SU Aurigae


  In this contribution we investigate how a disk determines the physical and
geometrical properties of the circumstellar environment of the T Tauri SU
Aurigae. Our model of the spectral energy distribution of this star includes
the central young star, a flat black disk and a diffuse envelope. We also
describe the inner interaction region between the disk and the star, the
magnetosphere, by analysing the accretion and wind signatures in several
spectral lines observed during the MUSICOS 96 campaign.

</DOC>
<DOC>
<DOCNO> 118146 </DOCNO>
Structure of the Circumnuclear Region of Seyfert 2 Galaxies Revealed by


  We report the Rossi X-ray Timing Explorer observations of the heavily
absorbed Seyfert 2 galaxy NGC 4945, which confirm the large column density of
the absorber, corresponding to the optical depth to Thomson scattering of about
2.4. The hard X-ray flux (8-30 keV) measured by us is rapidly variable with a
large amplitude, on time scales of a day or less. This implies that the bulk of
the extreme absorption does not originate in a parsec-size, geometrically thick
molecular torus: limits on the amount of scattered flux require that the
optically thick material on parsec scales must be rather geometrically thin,
subtending a half-angle of less than 10 degrees as seen from the nucleus. This
presents a problem in accounting for the Cosmic X-ray Background primarily with
AGN possessing such geometry.

</DOC>
<DOC>
<DOCNO> 122002 </DOCNO>
The impact of spanish astrophysics in the 1990's


  Spanish astronomy has grown rapidly during the 1990s. The number of papers
published per year has doubled, to about 4% of the world total. The number of
high-impact papers, however, remains constant at about 1% of the world total.
Papers from France, Germany and Italy also have lower impact than their numbers
suggest, while for the US, UK, Japan, Netherlands and Australia, the fraction
of high-impact papers is approximately the same as the fraction of all papers.
We suggest a few possible explanations for this difference.

</DOC>
<DOC>
<DOCNO> 71765 </DOCNO>
Constraints on T-Odd, P-Even Interactions from Electric Dipole Moments


  We construct the relationship between nonrenormalizable,effective,
time-reversal violating (TV) parity-conserving (PC) interactions of quarks and
gauge bosons and various low-energy TVPC and TV parity-violating (PV)
observables. Using effective field theory methods, we delineate the scenarious
under which experimental limits on permanent electric dipole moments (EDM's) of
the electron, neutron, and neutral atoms as well as limits on TVPC observables
provide the most stringent bounds on new TVPC interactions. Under scenarios in
which parity invariance is restored at short distances, the one-loop EDM of
elementary fermions generate the most severe constraints. The limits derived
from the atomic EDM of $^{199}$Hg are considerably weaker. When parity symmetry
remains broken at short distances, direct TVPC search limits provide the least
ambiguous bounds. The direct limits follow from TVPC interactions between two
quarks.

</DOC>
<DOC>
<DOCNO> 170065 </DOCNO>
Function-dependent Phase Transform in Quantum Computing


  We construct a quantum algorithm that performs function-dependent phase
transform and requires no initialization of an ancillary register. The
algorithm recovers the initial state of an ancillary register regardless of
whether its state is pure or mixed. Thus we can use any qubits as an ancillary
register even though they are entangled with others and are occupied by other
computational process. We also show that our algorithm is optimal in the sense
of the number of function evaluations.

</DOC>
<DOC>
<DOCNO> 84300 </DOCNO>
Effect of latent mass in inhomogeneous cosmological model with perfect


  The inhomogeneous cosmological model with matter in the form self-acting
scalar field and perfect fluid is considered. On the basis of exact solutions
is considered the evolution of density distribution of a matter in space on a
background cosmological expansion by the Universe. Is shown, the first, in such
model the equation of a matter state is variable in time and is closely
connected to character cosmological expansions. Secondly, it is shown with
point of view of the observer the Universe looks as space flat, but with effect
of latent mass. This effect consists in that the mass of a perfect fluid by
dynamic measurements surpasses the own mass perfect fluid that is explained by
presence scalar field (20K).

</DOC>
<DOC>
<DOCNO> 118391 </DOCNO>
Ambiguities in fits to the complex X-ray spectra of starburst galaxies


  Spectral fits to X-ray data from both NGC 253 and M 82 provide ambiguous
results. The so-called ``best fit'' results depend on the instrument with which
the data were obtained and obviously on the choice of spectral model
composition. We show that different spectral models can be fit equally well to
BeppoSAX data of both galaxies. Metallicities are unreliable in general, with a
strong dependence on the choice of model. Preference to one particular spectral
model can only be given by combining spectroscopic and imaging X-ray data from
all available satellites (ROSAT, ASCA, and BeppoSAX). Based on spectra of NGC
253, we demonstrate that a model consisting of two or more thermal plasma
components plus a hard power law continuum and Fe K alpha line emission can
explain all observations. These model components represent the integral
spectrum of thermal gas and compact sources in starburst galaxies that are most
likely supernova remnants and X-ray binaries. The same model can fit the X-ray
data of M 82, but there the evidence, from ROSAT imaging, of the existence of
compact sources which might represent high-mass X-ray binaries is weaker. This
implies that its hard X-ray emission, which is extended in ROSAT images, might
- if truly diffuse - be dominated by a very hot (several keV energy) thermal
gas component.

</DOC>
<DOC>
<DOCNO> 14152 </DOCNO>
Periodic instanton method and macroscopic quantum tunneling between two


  A new method is used to investigate the tunneling between two weakly-linked
Bose-Einstein condensates confined in double-well potential traps. The
nonlinear interaction between the atoms in each well contributes to a finite
chemical potential, which, with consideration of periodic instantons, leads to
a remarkably high tunneling frequency. This result can be used to interpret the
newly found Macroscopic Quantum Self Trapping (MQST) effect. Also a new kind of
first-order crossover between different regions is predicted.

</DOC>
<DOC>
<DOCNO> 83303 </DOCNO>
Bootstrapping a Tagged Corpus through Combination of Existing


  This paper describes a new method, Combi-bootstrap, to exploit existing
taggers and lexical resources for the annotation of corpora with new tagsets.
Combi-bootstrap uses existing resources as features for a second level machine
learning module, that is trained to make the mapping to the new tagset on a
very small sample of annotated corpus material. Experiments show that
Combi-bootstrap: i) can integrate a wide variety of existing resources, and ii)
achieves much higher accuracy (up to 44.7 % error reduction) than both the best
single tagger and an ensemble tagger constructed out of the same small training
sample.

</DOC>
<DOC>
<DOCNO> 170025 </DOCNO>
Is the Universe a Quantum System?


  In order to relate the probabilistic predictions of quantum theory uniquely
to measurement results, one has to conceive of an ensemble of identically
prepared copies of the quantum system under study. Since the universe is the
total domain of physical experience, it cannot be copied, not even in a thought
experiment. Therefore, a quantum state of the whole universe can never be made
accessible to empirical test. Hence the existence of such a state is only a
metaphysical idea. Despite prominent claims to the contrary, recent
developments in the quantum-interpretation debate do not invalidate this
conclusion.

</DOC>
<DOC>
<DOCNO> 13485 </DOCNO>
Electronic response of aligned multishell carbon nanotubes


  We report calculations of the effective electronic response of aligned
multishell carbon nanotubes. A local graphite-like dielectric tensor is
assigned to every point of the multishell tubules, and the effective transverse
dielectric function of the composite is computed by solving Maxwell's
equations. Calculations of both real and imaginary parts of the effective
dielectric function are presented, for various values of the filling fraction
and the ratio of the internal and external radii of hollow tubules. Our full
calculations indicate that the experimentally measured macroscopic dielectric
function of carbon nanotube materials is the result of a strong electromagnetic
coupling between the tubes, which cannot be accounted for with the use of
simplified effective medium theories. The presence of surface plasmons is
investigated, and both optical absorption cross sections and energy-loss
spectra of aligned tubules are calculated.

</DOC>
<DOC>
<DOCNO> 151371 </DOCNO>
Constraint Supersymmetry Breaking and Non-Perturbative Effects in String


  We discuss supersymmetry breaking mechanism at the level of low energy N=1
effective superstring actions that exhibit $SL(2,Z)_T$ target space modular
duality or $SL(2,Z)_S$ strong-weak coupling duality. The allowed superpotential
forms use the assumption that the sourse of non-perturbative effects is not
specified and as a result represent the most general parametrization of
non-perturbative effects. We found that the allowed non-perturbative
superpotential is severely constrained when we use the cusp forms of the
modular group for its construction. By construction the poles of the
superpotential are either inside the fundamental domain or beyond. We also
found limits on the parameters of the superpotential by demanding that the
truncated potential for the gaugino condensate never breaks down at finite
values in the moduli space. The latter constitutes a criterion for avoiding
poles in the fundamental domain. However, the potential in most of the cases
avoids naturally singularities inside the fundamental domain, rendering the
potential finite. The minimum values of the limits on the parameters in the
superpotential may correspond to vacua with vanishing cosmological constant.

</DOC>
<DOC>
<DOCNO> 121446 </DOCNO>
The Faint Sky Variability Survey I: An Overview


  The Faint Sky Variability Survey is aimed at finding variable objects in the
brightness range between 17th and 25th magnitude on timescales between tens of
minutes and years with photometric precisions ranging from 3 millimagnitudes
for the brightest to 0.2 magnitudes for the faintest objects. An area of at
least 50 square degrees, located at mid-galactic latitudes, will be covered
using the Wide Field Camera on the 2.5m Isaac Newton Telescope on La Palma. The
survey started in November 1998 as part of the INT Wide Field Survey program.
Here we describe the main goals of the Faint Sky Variability Survey, the
methods used in extracting the relevant information and the future prospects of
the survey.

</DOC>
<DOC>
<DOCNO> 117925 </DOCNO>
Testing the SOC hypothesis for the magnetosphere


  As noted by Chang, the hypothesis of Self-Organised Criticality provides a
theoretical framework in which the low dimensionality seen in magnetospheric
indices can be combined with the scaling seen in their power spectra and the
recently-observed plasma bursty bulk flows. As such, it has considerable
appeal, describing the aspects of the magnetospheric fuelling:storage:release
cycle which are generic to slowly-driven, interaction-dominated, thresholded
systems rather than unique to the magnetosphere. In consequence, several recent
numerical "sandpile" algorithms have been used with a view to comparison with
magnetospheric observables. However, demonstration of SOC in the magnetosphere
will require further work in the definition of a set of observable properties
which are the unique "fingerprint" of SOC. This is because, for example, a
scale-free power spectrum admits several possible explanations other than SOC.
  A more subtle problem is important for both simulations and data analysis
when dealing with multiscale and hence broadband phenomena such as SOC. This is
that finite length systems such as the magnetosphere or magnetotail will by
definition give information over a small range of orders of magnitude, and so
scaling will tend to be narrowband. Here we develop a simple framework in which
previous descriptions of magnetospheric dynamics can be described and
contrasted. We then review existing observations which are indicative of SOC,
and ask if they are sufficient to demonstrate it unambiguously, and if not,
what new observations need to be made?

</DOC>
<DOC>
<DOCNO> 12774 </DOCNO>
Carrier relaxation with LO phonon decay in semiconductor quantum dots


  Analysis of an exactly soluble model of phonons coupled to a carrier in a
quantum dot provides a clear illustration of a phonon bottleneck to relaxation.
The introduction of three-phonon interactions leads to a broad window for
relaxation by the processes of LO phonon scattering and decay.

</DOC>
<DOC>
<DOCNO> 71190 </DOCNO>
Equation of state of resonance-rich matter in the central cell in


  The equilibration of hot and dense nuclear matter produced in the central
cell of central Au+Au collisions at RHIC ($\sqrt{s}=200$ AGeV) energies is
studied within a microscopic transport model. The pressure in the cell becomes
isotropic at $t\approx 5$ fm/$c$ after beginning of the collision. Within the
next 15 fm/$c$ the expansion of matter in the cell proceeds almost
isentropically with the entropy per baryon ratio $S/A \approx 150$, and the
equation of state in the $(P,\epsilon)$ plane has a very simple form,
$P=0.15\epsilon$. Comparison with the statistical model of an ideal hadron gas
indicates that the time $t \approx 20$ fm/c may be too short to reach the fully
equilibrated state. Particularly, the creation of long-lived resonance-rich
matter in the cell decelerates the relaxation to chemical equilibrium. This
resonance-abundant state can be detected experimentally after the thermal
freeze-out of particles.

</DOC>
<DOC>
<DOCNO> 80850 </DOCNO>
Spinodal Decomposition in Finite Temperature SU(2) and SU(3)


  After a rapid increase in temperature across the deconfinement temperature
T_d to temperatures T >> T_d, pure gauge theories exhibit unstable long
wavelength fluctuations in the approach to equilibrium. This phenomenon is
analogous to spinodal decomposition observed in condensed matter physics, and
also seen in models of disordered chiral condensate formation. At high
temperature, the unstable modes occur only in the range 0 < k < k_c, where k_c
is on the order of the Debye screening mass m_D. Equilibration always occurs
via spinodal decomposition for SU(2). For SU(3) at T near T_d, nucleation
replaces spinodal decomposition as the dominant equilibration mechanism. Monte
Carlo simulations of SU(2) and SU(3) lattice gauge theories exhibit the
predicted phenomena. For SU(2), the observed value of k_c is in reasonable
agreement with a value predicted from previous lattice measurements of m_D.

</DOC>
<DOC>
<DOCNO> 169756 </DOCNO>
Lambda's, V's and optimal cloning with stimulated emission


  We show that optimal universal cloning of the polarization state of photons
can be achieved via stimulated emission in three-level systems, both of the
Lambda and the V type. We establish the equivalence of our systems with coupled
harmonic oscillators, which permits us to analyze the structure of the cloning
transformations realized. These transformations are shown to be equivalent to
the optimal cloning transformations for qubits discovered by Buzek and Hillery,
and Gisin and Massar. The down-conversion cloner discovered previously by some
of the authors is obtained as a limiting case. We demonstrate an interesting
equivalence between systems of Lambda atoms and systems of pairwise entangled V
atoms. Finally we discuss the physical differences between our photon cloners
and the qubit cloners considered previously and prove that the bounds on the
fidelity of the clones derived for qubits also apply in our situation.

</DOC>
<DOC>
<DOCNO> 84662 </DOCNO>
On space-times admitting shear-free, irrotational, geodesic null


  Space-times admitting a shear-free, irrotational, geodesic null congruence
are studied. Attention is focused on those space-times in which the
gravitational field is a combination of a perfect fluid and null radiation.

</DOC>
<DOC>
<DOCNO> 9299 </DOCNO>
Reversible and irreversible evolution of a condensed bosonic gas


  We have formulated a kinetic theory for a condensed atomic gas in a trap,
i.e., a generalized Gross-Pitaevskii equation, as well as a quantum-Boltzmann
equation for the normal and anomalous fluctuations [R. Walser et al., Phys.
Rev. A, 59, 3878 (1999)]. In this article, the theory is applied to the case of
an isotropic configuration and we present numerical and analytical results for
the reversible real-time propagation, as well as irreversible evolution towards
equilibrium.

</DOC>
<DOC>
<DOCNO> 116513 </DOCNO>
Informational interpretation of quantum mechanics


  Ascribing to inanimate matter a possibility to receive, work on and transfer
information allows us to explain quantum-mechanical phenomena including
"delayed-choice"- and "Einstein-Podolsky-Rosen (EPR)"-type experiments adhering
to the basis of local realism, and to suggest essentially new experiments with
microparticles and atoms in which information plays the principal role.

</DOC>
<DOC>
<DOCNO> 67775 </DOCNO>
TeV Strings and Collider Probes of Large Extra Dimensions


  Arkani-Hamed, Dimopoulos, and Dvali have proposed that the fundamental
gravitational scale is close to 1 TeV, and that the observed weakness of
gravity at long distances is explained by the presence of large extra compact
dimensions. If this scenario is realized in a string theory of quantum gravity,
the string excited states of Standard Model particles will also have TeV
masses. These states will be visible to experiment and in fact provide the
first signatures of the presence of a low quantum gravity scale. Their presence
also affects the more familiar signatures due to real and virtual graviton
emission. We study the effects of these states in a simple string model.

</DOC>
<DOC>
<DOCNO> 122566 </DOCNO>
Particle Acceleration and Diffusion in Fossil Radio Plasma


  The strong activity of radio galaxies should have led to a nearly ubiquitous
presence of fossil radio plasma in the denser regions of the inter-galactic
medium as clusters, groups and filaments of galaxies. This fossil radio plasma
can contain large quantities of relativistic particles (electrons and possibly
protons) by magnetic confinement. These particles might be released and/or
re-energized under environmental influences as turbulence and shock waves.
Possible connections of such processes to the formation of the observed sources
of diffuse radio emission in clusters of galaxies (the cluster radio halos and
the cluster radio relics) are discussed.

</DOC>
<DOC>
<DOCNO> 120960 </DOCNO>
Recent X-ray Observations of Disk Galaxies: Tracing the Dynamic


  I review recent results from our deep ROSAT and Chandra observations of two
galaxies, M101 and NGC 4631, in fields of exceptionally low Galactic
extinction. Large amounts of X-ray-emitting gas are detected in these galaxies.
Such gas is produced primarily in massive star forming regions and have an
average characteristic temperature of a few times $10^6$ K. Cooler gas ($\sim
10^6$ K) is found typically outside galactic disks and may represent outflows
from blown-out superbubbles. Propagation of star formation, driven by the
expansion of hot gas, appears to be operating in giant HII complexes. A
substantial fraction of photo-evaporated gas in such complexes may be
mass-loaded into hot gas, which explains their large X-ray luminosities. These
processes likely play an important role in determining the global properties of
the interstellar medium, especially the disk/halo interaction.

</DOC>
<DOC>
<DOCNO> 169732 </DOCNO>
Fast quantum gates for cold trapped ions


  We present an alternative scheme for the generation of a 2-qubit quantum gate
interaction between laser-cooled trapped ions. The scheme is based on the AC
Stark shift (lightshift) induced by laser light resonant with the ionic
transition frequency. At {\it specific} laser intensities, the shift of the
ionic levels allows the resonant excitation of transitions involving the
exchange of motional quanta. We compare the performance of this scheme with
respect to that of related ion-trap proposals and find that, for an
experimental realisation using travelling-wave radiation and working in the
Lamb-Dicke regime, an improvement of over an order of magnitude in the gate
switching rate is possible.

</DOC>
<DOC>
<DOCNO> 70632 </DOCNO>
Instantaneous Bethe-Salpeter equation: utmost analytic approach


  The Bethe-Salpeter formalism in the instantaneous approximation for the
interaction kernel entering into the Bethe-Salpeter equation represents a
reasonable framework for the description of bound states within relativistic
quantum field theory. In contrast to its further simplifications (like, for
instance, the so-called reduced Salpeter equation), it allows also the
consideration of bound states composed of "light" constituents. Every
eigenvalue equation with solutions in some linear space may be (approximately)
solved by conversion into an equivalent matrix eigenvalue problem. We
demonstrate that the matrices arising in these representations of the
instantaneous Bethe-Salpeter equation may be found, at least for a wide class
of interactions, in an entirely algebraic manner. The advantages of having the
involved matrices explicitly, i.e., not "contaminated" by errors induced by
numerical computations, at one's disposal are obvious: problems like, for
instance, questions of the stability of eigenvalues may be analyzed more
rigorously; furthermore, for small matrix sizes the eigenvalues may even be
calculated analytically.

</DOC>
<DOC>
<DOCNO> 12241 </DOCNO>
Density of a gas of spin polarized fermions in a magnetic field


  For a fermion gas with equally spaced energy levels that is subjected to a
magnetic field, the particle density is calculated. The derivation is based on
the path integral approach for identical particles, in combination with the
inversion techniques for the generating function of the static response
functions. Explicit results are presented for the ground state density as a
function of the magnetic field with a number of particles ranging from 1 to 45.

</DOC>
<DOC>
<DOCNO> 121621 </DOCNO>
Chemical abundances in the inner 5 kpc of the Galactic disk


  High-resolution, high signal-to-noise spectral data are presented for four
young B-type stars lying towards the Galactic Centre. Determination of their
atmospheric parameters from their absorption line profiles, and uvby
photometric measurement of the continua indicate that they are massive objects
lying slightly out of the plane, and were probably born in the disk between
2.5-5 kpc from the Centre. We have carried out a detailed absolute and
differential line-by-line abundance analyses of the four stars compared to two
stars with very similar atmospheric parameters in the solar neighbourhood. The
stars appear to be rich in all the well sampled chemical elements (C, N, Si,
Mg, S, Al), except for oxygen. Oxygen abundances derived in the atmospheres of
these four stars are very similar to that in the solar neighbourhood. If the
photospheric composition of these young stars is reflective of the gaseous ISM
in the inner Galaxy, then the values derived for the enhanced metals are in
excellent agreement with the extrapolation of the Galactic abundance gradients
previously derived by Rolleston et al. (2000) and others. However, the data for
oxygen suggests that the inner Galaxy may not be richer than normal in this
element, and the physical reasons for such a scenario are unclear.

</DOC>
<DOC>
<DOCNO> 152326 </DOCNO>
A spinor-like representation of the contact superconformal algebra K'(4)


  In this work we construct an embedding of a nontrivial central extension of
the contact superconformal algebra K'(4) into the Lie superalgebra of
pseudodifferential symbols on the supercircle S^{1|2}. Associated with this
embedding is a one-parameter family of spinor-like tiny irreducible
representations of K'(4) realized just on 4 fields instead of the usual 16.

</DOC>
<DOC>
<DOCNO> 68426 </DOCNO>
Charm multiplicity and the branching ratios of inclusive charmless b


  In the framework of general two-Higgs-doublet models, we calculate the
branching ratios of various inclusive charmless b decays by using the low
energy effective Hamiltonian including next-to-leading order QCD corrections,
and examine the current status and the new physics effects on the determination
of the charm multiplicity $n_c$ and semileptonic branching ratio $B_{SL}$.
Within the considered parameter space, the enhancement to the ratio $BR(b \to s
g)$ due to the charged-Higgs penguins can be as large as a factor of 8 (3) in
the model III (II), while the ratio $BR(b \to no charm)$ can be increased from
the standard model prediction of 2.49% to 4.91% (2.99%) in the model III (II).
Consequently, the value of $B_{SL}$ and $n_c$ can be decreased simultaneously
in the model III. The central value of $B_{SL}$ will be lowered slightly by
about 0.003, but the ratio $n_c$ can be reduced significantly from the
theoretical prediction of $n_c= 1.28 \pm 0.05$ in the SM to $n_c= 1.23 \pm
0.05$, $1.18 \pm 0.05$ for $m_{H^+}=200, 100$ GeV, respectively. We find that
the predicted $n_c$ and the measured $n_c$ now agree within roughly one
standard deviation after taking into account the effects of gluonic charged
Higgs penguins in the model III with a relatively light charged Higgs boson.

</DOC>
<DOC>
<DOCNO> 13848 </DOCNO>
Analysis of the temperature-dependent quantum point contact conductance


  The temperature dependence of the conductance of a quantum point contact has
been measured. The conductance as a function of the Fermi energy shows
temperature-independent fixed points, located at roughly multiple integers of
$e^{2}/h$. Around the first fixed point at e$^{2}$/h, the experimental data for
different temperatures can been scaled onto a single curve. For pure thermal
smearing of the conductance steps, a scaling parameter of one is expected. The
measured scaling parameter, however, is significantly larger than 1. The
deviations are interpreted as a signature of the potential landscape of the
quantum point contact, and of the source-drain bias voltage. We relate our
results phenomenologically to the metal-insulator transition in two dimensions.

</DOC>
<DOC>
<DOCNO> 70097 </DOCNO>
The semileptonic decays of the B_c meson


  We study the semileptonic transitions B_c to \eta_c, J/\psi, D, D^*, B, B^*,
B_s, B_s^* in the framework of a relativistic constituent quark model. We use
experimental data on leptonic J/\psi decay, lattice and QCD sum rule results on
leptonic B_c decay, and on radiative \eta_c transitions to adjust the quark
model parameters. We compute all form factors of the above semileptonic
B_c-transitions and give predictions for various semileptonic B_c decay modes
including their \tau-modes when they are kinematically accessible. The
implications of heavy quark symmetry for the semileptonic decays are discussed
and are shown to be manifest in our explicit relativistic quark model
calculation. A comparison of our results with the results of other calculations
is performed.

</DOC>
<DOC>
<DOCNO> 72095 </DOCNO>
Further Evidence for Cosmological Evolution of the Fine Structure


  We describe the results of a search for time variability of the fine
structure constant, alpha, using absorption systems in the spectra of distant
quasars. Three large optical datasets and two 21cm/mm absorption systems
provide four independent samples, spanning 23% to 87% of the age of the
universe. Each sample yields a smaller alpha in the past and the optical sample
shows a 4-sigma deviation: da/a = -0.72 +/- 0.18 x 10^{-5} over the redshift
range 0.5 < z < 3.5. We find no systematic effects which can explain our
results. The only potentially significant systematic effects push da/a towards
positive values, i.e. our results would become more significant were we to
correct for them.

</DOC>
<DOC>
<DOCNO> 85193 </DOCNO>
Conditional Symmetries, the True Degree of Freedom and G.C.T. Invariant


  The quantization of the most general Bianchi Type II geometry -with all six
scale factors, as well as the lapse function and the shift vector, present- is
considered. In an earlier work, a first reduction of the initial 6-dimensional
configuration space, to a 4-dimensional one, has been achieved by the usage of
the information furnished by the quantum form of the linear constraints.
Further reduction of the space in which the wave function -obeying the
Wheeler-DeWitt equation- lives, is accomplished by unrevealling the extra
symmetries of the Hamiltonian. These symmetries appear in the form of -linear
in momenta- first integrals of motion. Most of these symmetries, correspond to
G.C.T.s through the action of the automorphism group. Thus, a G.C.T. invariant
wave function is found, which depends on the only true degree of freedom, i.e.
the unique curvature invariant, characterizing the hypersurfaces t=const.

</DOC>
<DOC>
<DOCNO> 102465 </DOCNO>
Quantum tori, mirror symmetry and deformation theory


  We suggest to compactify the universal covering of the moduli space of
complex structures by non-commutative spaces. The latter are described by
certain categories of sheaves with connections which are flat along foliations.
In the case of abelian varieties this approach gives quantum tori as a
non-commutative boundary of the moduli space. Relations to mirror symmetry,
modular forms and deformation theory are discussed.

</DOC>
<DOC>
<DOCNO> 121300 </DOCNO>
ASCA Observations of the Twin Supernova Remnants in the Large Magellanic


  We report results from an ASCA X-ray study of DEM L316, an emission nebula in
the Large Magellanic Cloud (LMC) consisting of two closely-spaced supernova
remnants (SNRs). The SIS image shows separate X-ray sources located at the
positions of the two radio- and optically-emitting SNR shells, 0547$-$69.7A and
0547$-$69.7B (hereafter, shell A and B). The individual X-ray spectrum of each
shell is well described by optically-thin thermal emission, although the
characteristics of the emission differ in important details between them. Shell
A exhibits strong iron L emission, which we attribute to the presence of
iron-rich ejecta leading to the suggestion that this SNR originates from a Type
Ia SN, an explosion of a moderate mass progenitor. Shell B, on the other hand,
has a chemical composition similar to that of the interstellar medium of the
LMC and so its X-ray emission is dominated by swept-up matter. The different
spectral features strongly disfavor the hypothesis that the two shells are due
to one supernova explosion into an interconnected bubble. We could not obtain
the evidence which positively supports the collision between two SNRs.

</DOC>
<DOC>
<DOCNO> 169945 </DOCNO>
Quantum Clock Synchronization Based on Shared Prior Entanglement


  We demonstrate that two spatially separated parties (Alice and Bob) can
utilize shared prior quantum entanglement, and classical communications, to
establish a synchronized pair of atomic clocks. In contrast to classical
synchronization schemes, the accuracy of our protocol is independent of Alice
or Bob's knowledge of their relative locations or of the properties of the
intervening medium.

</DOC>
<DOC>
<DOCNO> 99474 </DOCNO>
An Exact Approach to the Oscillator Radiation Process in an Arbitrarily


  Starting from a solution of the problem of a mechanical oscillator coupled to
a scalar field inside a reflecting sphere of radius $R$, we study the behaviour
of the system in free space as the limit of an arbitrarily large radius in the
confined solution. From a mathematical point of view we show that this way of
facing the problem is not equivalent to consider the system {\it a} {\it
priori} embedded in infinite space. In particular, the matrix elements of the
transformation turning the system to principal axis, do not tend to
distributions in the limit of an arbitrarily large sphere as it should be the
case if the two procedures were mathematically equivalent. Also, we introduce
"dressed" coordinates which allow an exact description of the oscillator
radiation process for any value of the coupling, strong or weak. In the case of
weak coupling, we recover from our exact expressions the well known decay
formulas from perturbation theory.

</DOC>
<DOC>
<DOCNO> 169839 </DOCNO>
Fidelity balance in quantum operations


  I derive a tight bound between the quality of estimating the state of a
single copy of a $d$-level system, and the degree the initial state has to be
altered in course of this procedure. This result provides a complete analytical
description of the quantum mechanical trade-off between the information gain
and the quantum state disturbance expressed in terms of mean fidelities. I also
discuss consequences of this bound for quantum teleportation using nonmaximally
entangled states.

</DOC>
<DOC>
<DOCNO> 67805 </DOCNO>
Testing Nonperturbative Ansaetze for the QCD Field Strength Correlator


  A test for the Gaussian and exponential Ansaetze for the nonperturbative
parts of the coefficient functions, D^{nonpert.} and D_1^{nonpert.}, which
parametrize the gauge-invariant bilocal correlator of the field strength
tensors in the stochastic vacuum model of QCD, is proposed. It is based on the
evaluation of the heavy-quark condensate within this model by making use of the
world-line formalism and equating the obtained result to the one following
directly from the QCD Lagrangian. This yields a certain relation between
D^{nonpert.}(0) and D_1^{nonpert.}(0), which is further compared with an
analogous relation between these quantities known from the existing lattice
data. Such a comparison leads to the conclusion that at the distances smaller
than the correlation length of the vacuum, Gaussian Ansatz is more suitable
than the exponential one.

</DOC>
<DOC>
<DOCNO> 150530 </DOCNO>
First order quantum corrections to the classical reflection factor of


  The sinh-Gordon model is restricted to a half-line by boundary conditions
maintaining integrability. A perturbative calculation of the reflection factor
is given to one loop order in the bulk coupling and to first order in the
difference of the two parameters introduced at the boundary, providing a
further verification of Ghoshal's formula. The calculation is consistent with a
conjecture for the general dependence of the reflection factor on the boundary
parameters and the bulk coupling.

</DOC>
<DOC>
<DOCNO> 80702 </DOCNO>
Instability in the Molecular Dynamics Step of Hybrid Monte Carlo in


  We investigate instability and reversibility within Hybrid Monte Carlo
simulations using a non-perturbatively improved Wilson action. We demonstrate
the onset of instability as tolerance parameters and molecular dynamics step
sizes are varied. We compare these findings with theoretical expectations and
present limits on simulation parameters within which a stable and reversible
algorithm is obtained for physically relevant simulations. Results of
optimisation experiments with respect to tolerance prarameters are also
presented.

</DOC>
<DOC>
<DOCNO> 150578 </DOCNO>
Geodesics and Newton's Law in Brane Backgrounds


  In brane world models our universe is considered as a brane imbedded into a
higher dimensional space. We discuss the behaviour of geodesics in the
Randall-Sundrum background and point out that free massive particles cannot
move along the brane only. The brane is repulsive, and matter will be expelled
from the brane into the extra dimension. This is rather undesirable, and hence
we study an alternative model with a non-compact extra dimension, but with an
attractive brane embedded into the higher dimensional space. We study the
linearized gravity equations and show that Newton's gravitational law is valid
on the brane also in the alternative background.

</DOC>
<DOC>
<DOCNO> 150838 </DOCNO>
Noncommutative Monopole from Nonlinear Monopole


  We solve the non-linear monopole equation of the Born-Infeld theory to all
orders in the NS 2-form and give physical implications of the result. The
solution is constructed by extending the earlier idea of rotating the brane
configuration of the Dirac monopole in the target space. After establishing the
non-linear monopole, we explore the non-commutative monopole by the
Seiberg-Witten map.

</DOC>
<DOC>
<DOCNO> 152516 </DOCNO>
The BPS Spectrum of N=2 SU(N) SYM and Parton Branes


  We apply ideas that have appeared in the study of D-branes on Calabi-Yau
compactifications to the derivation of the BPS spectrum of field theories. In
particular, we identify an orbifold point whose fractional branes can be
thought of as ``partons'' of the BPS spectrum of N=2 pure SU(N) SYM. We derive
the BPS spectrum and lines of marginal stability branes near that orbifold, and
compare our results with the spectrum of the field theories.

</DOC>
<DOC>
<DOCNO> 116891 </DOCNO>
LEDA Beam Operations Milestone and Observed Beam Transmission


  Recently, the Low-Energy Demonstration Accelerator (LEDA) portion of the
Accelerator Production of Tritium (APT) project reached its 100-mA, 8-hr CW
beam operation milestone. LEDA consists of a 75-keV proton injector, 6.7-MeV,
350-MHz CW radio-frequency quadrupole (RFQ) with associated high-power and
low-level rf systems, a short high-energy beam transport (HEBT) and high-power
(670-kW CW) beam dump. During the commissioning phase it was discovered that
the RFQ field level must to be approximately 5-10% higher than design in order
to accelerate the full 100-mA beam with low losses. Measurements of a
low-duty-factor, 100-mA beam show the beam transmission is unexpectedly low for
RFQ field levels between ~90 and 105% of design. This paper will describe some
aspects of LEDA operations critical to achieving the above milestone.
Measurement and simulation results for reduced RFQ beam transmission near
design operating conditions are also presented.

</DOC>
<DOC>
<DOCNO> 84346 </DOCNO>
Measurement Theory and General Relativity


  The theory of measurement is employed to elucidate the physical basis of
general relativity. For measurements involving phenomena with intrinsic length
or time scales, such scales must in general be negligible compared to the
(translational and rotational) scales characteristic of the motion of the
observer. Thus general relativity is a consistent theory of coincidences so
long as these involve classical point particles and electromagnetic rays
(geometric optics). Wave optics is discussed and the limitations of the
standard theory in this regime are pointed out. A nonlocal theory of
accelerated observers is briefly described that is consistent with observation
and excludes the possibility of existence of a fundamental scalar field in
nature.

</DOC>
<DOC>
<DOCNO> 11402 </DOCNO>
Modelling High-frequency Economic Time Series


  The minute-by-minute move of the Hang Seng Index (HSI) data over a four-year
period is analysed and shown to possess similar statistical features as those
of other markets. Based on a mathematical theorem [S. B. Pope and E. S. C.
Ching, Phys. Fluids A {\bf 5}, 1529 (1993)], we derive an analytic form for the
probability distribution function (PDF) of index moves from fitted functional
forms of certain conditional averages of the time series. Furthermore,
following a recent work by Stolovitzky and Ching, we show that the observed PDF
can be reproduced by a Langevin process with a move-dependent noise amplitude.
The form of the Langevin equation can be determined directly from the market
data.

</DOC>
<DOC>
<DOCNO> 14142 </DOCNO>
Critical Dynamics of Thermal Conductivity at the Normal-Superconducting


  We study the effect of thermal fluctuations on the critical dynamics of the
three-dimensional disordered superconductor across the normal-superconducting
transition. We employ a phenomenological hydrodynamic approach, and in
particular find the thermal conductivity to be smooth and non-singular at the
transition.

</DOC>
<DOC>
<DOCNO> 118925 </DOCNO>
Astrometry of the Omega Centauri Hubble Space Telescope Calibration


  Astrometry, on the International Celestial Reference Frame (epoch J2000.0),
is presented for the Walker (1994, PASP, 106, 828) stars in the Omega Centauri
(= NGC 5139 = C1323-1472) Hubble Space Telescope Wide Field/Planetary Camera
(WF/PC) calibration field of Harris et al. (1993, AJ, 105, 1196). Harris et al.
stars were first identified on a WFPC2 observation of the omega Cen HST
calibration field. Relative astrometry of the Walker stars in this field was
then obtained using Walker's CCD positions and astrometry derived using the
STSDAS METRIC task on the positions of the Harris et al. stars on the WFPC2
observation. Finally, the relative astrometry, which was based on the HST Guide
Star Catalog, is placed on the International Celestial Reference Frame with
astrometry from the USNO-A2.0 catalog. An ASCII text version of the astrometric
data of the Walker stars in the omega Cen HST calibration field is available
electronically in the online version of the article.

</DOC>
<DOC>
<DOCNO> 9683 </DOCNO>
Coulomb gap in the quantum Hall insulator


  We calculate numerically the spectrum of disordered electrons in the lowest
Landau level at filling factor 1/5 using the self-consistent Hartree-Fock
approximation for systems containing up to 400 flux quanta. Special attention
is paid to the correct treatment of the q=0 component of the Coulomb
interaction. For sufficiently strong disorder, the system is an insulator at
this filling factor. We observe numerically a Coulomb gap in the
single-particle density of states (DOS). The DOS agrees quantitatively with the
predictions for classical point charges.

</DOC>
<DOC>
<DOCNO> 152140 </DOCNO>
Gauss-Bonnet interaction in Randall-Sundrum compactification


  We show that the Gauss-Bonnet term is the only consistent curvature squared
interaction in the Randall-Sundrum model and various static and inflationary
solutions can be found. And from metric perturbations around the RS background
with a single brane embedded, we also show that for a vanishing Gauss-Bonnet
coefficient, the brane bending allows us to reproduce the 4D Einstein gravity
at the linearized level.

</DOC>
<DOC>
<DOCNO> 170809 </DOCNO>
The information capacity of the lambda-system--photon field channel


  The potentially attainable information capacity of a radiatively stable
lambda-system, viewed as the input of a quantum information channel, is
studied. The output of the channel is formed by the states of the photon field
with optical excitation frequencies, which are created as a result of Raman
pumping. The analysis is based on the notion of coherent information.

</DOC>
<DOC>
<DOCNO> 116859 </DOCNO>
Phase Rotation, Cooling And Acceleration Of Muon Beams: A Comparison Of


  Experimental and theoretical activities are underway at CERN with the aim of
examining the feasibility of a very-high-flux neutrino source. In the present
scheme, a high-power proton beam (some 4 MW) bombards a target where pions are
produced. The pions are collected and decay to muons under controlled optical
condition. The muons are cooled and accelerated to a final energy of 50 GeV
before being injected into a decay ring where they decay under well-defined
conditions of energy and emittance.
 We present the most challenging parts of the whole scenario, the muon capture,
the ionisation-cooling and the first stage of the muon acceleration. Different
schemes, their performance and the technical challenges are compared.

</DOC>
<DOC>
<DOCNO> 121177 </DOCNO>
Black Hole Mass, Velocity Dispersion and the Radio Source in AGN


  The recent discovery of a correlation between nuclear black hole mass, M_bh,
and the stellar velocity dispersion (Gebhardt et al. 2000, Ferrarese and
Merritt 2000), in elliptical galaxies and spiral bulges, has raised the
question whether such a relationship exists for AGN. Estimates of M_bh for many
AGN, made using reverberation mapping techniques, allow exploration of the
relationship between black hole mass, the host galaxy and the energetics of
nuclear emission. However, since only a few AGN have both M_bh and velocity
dispersion measurements, we use the [OIII] 5007 emission line widths on the
assumption that for most AGN the forbidden line kinematics are dominated by
virial motion in the host galaxy bulge. We find that a relation does exist
between M_bh and [OIII] line width for AGN which is similar to the one found by
Gebhardt et al. 2000, although with more scatter as expected if secondary
influences on the gas kinematics are also present. Our conclusion is that both
active and inactive galaxies follow the same relationship between black hole
mass and bulge gravitational potential. We find no compelling evidence for
systematic differences in the mass estimates from reverberation mapping and
stellar dynamics. We also find that for radio quiet AGN the radio power and
black hole mass are highly correlated linking emission on scales of kiloparsecs
with the nuclear energy source.

</DOC>
<DOC>
<DOCNO> 8477 </DOCNO>
Shape anisotropy and Voids


  Numerical simulations on a 2-dimensional model system showed that voids are
induced primarily due to shape anisotropy in binary mixtures of interacting
disks. The results of such a simple model account for the key features seen in
a variety of flux experiments using liposomes and biological membranes.

</DOC>
<DOC>
<DOCNO> 40519 </DOCNO>
Neutral Hyperon and H-Dibaryon Results from KTeV


  Results from the KTeV experiment at Fermilab using neutral Xi hyperons are
presented, especially the first form-factor (FF) measurement from its
semi-leptonic decay. This decay, which is an important test of the Standard
Model, was observed for the first time using the 1997 KTeV experiment. We also
report on the analysis of a large samples of neutral Xi weak radiative decays,
and a search for the decay of a lightly bound $H^0$ dibaryon.

</DOC>
<DOC>
<DOCNO> 67890 </DOCNO>
The two-body electromagnetic pulsar


  The power spectrum formula of the synchrotron radiation generated by the
electron and positron moving at the opposite angular velocities in homogenous
magnetic field is derived in the Schwinger version of quantum field theory. The
asymptotical form of this formula is found. It is surprising that the spectrum
depends periodically on radiation frequency omega which means that the system
composed from electron, positron and magnetic field forms the two-body
electromagnetic pulsar.

</DOC>
<DOC>
<DOCNO> 84224 </DOCNO>
Classical Topology and Quantum States


  Any two infinite-dimensional (separable) Hilbert spaces are unitarily
isomorphic. The sets of all their self-adjoint operators are also therefore
unitarily equivalent. Thus if all self-adjoint operators can be observed, and
if there is no further major axiom in quantum physics than those formulated for
example in Dirac's `Quantum Mechanics', then a quantum physicist would not be
able to tell a torus from a hole in the ground. We argue that there are indeed
such axioms involving observables with smooth time evolution: they contain
commutative subalgebras from which the spatial slice of spacetime with its
topology (and with further refinements of the axiom, its $C^K-$ and $C^\infty-$
structures) can be reconstructed using Gel'fand - Naimark theory and its
extensions. Classical topology is an attribute of only certain quantum
observables for these axioms, the spatial slice emergent from quantum physics
getting progressively less differentiable with increasingly higher excitations
of energy and eventually altogether ceasing to exist. After formulating these
axioms, we apply them to show the possibility of topology change and to discuss
quantized fuzzy topologies. Fundamental issues concerning the role of time in
quantum physics are also addressed.

</DOC>
<DOC>
<DOCNO> 13395 </DOCNO>
On the Nagaoka polaron in the t-J model


  It is widely believed that a single hole in the two (or three) dimensional
t-J model, for sufficiently small exchange coupling J, creates a ferromagnetic
bubble around itself, a finite J remnant of the ferromagnetic groundstate at
J=0 (the infinite U Hubbard model), first established by Nagaoka. We
investigate this phenomenon in two dimensions using the density matrix
renormalization group, for system sizes up to 9x9. We find that the polaron
forms for J/t<0.02-0.03 (a somewhat larger value than estimated previously).
Although finite-size effects appear large, our data seems consistent with the
expected 1.1(J/t)^{-1/4} variation of polarion radius. We also test the
Brinkman-Rice model of non-retracing paths in a Neel background, showing that
it is quite accurate, at larger J. Results are also presented in the case where
the
 Heisenberg interaction is dropped (the t-J^z model). Finally we discuss a
"dressed polaron" picture in which the hole propagates freely inside a finite
region but makes only self-retracing excursions outside this region.

</DOC>
<DOC>
<DOCNO> 8191 </DOCNO>
Time Dependent Theory for Random Lasers


  A model to simulate the phenomenon of random lasing is presented. It couples
Maxwell's equations with the rate equations of electronic population in a
disordered system. Finite difference time domain methods are used to obtain the
field pattern and the spectra of localized lasing modes inside the system. A
critical pumping rate $P_{r}^{c}$ exists for the appearance of the lasing
peaks. The number of lasing modes increase with the pumping rate and the length
of the system. There is a lasing mode repulsion. This property leads to a
saturation of the number of modes for a given size system and a relation
between the localization length $\xi$ and average mode length $L_m$.

</DOC>
<DOC>
<DOCNO> 121128 </DOCNO>
Isolated neutron stars discovered by ROSAT


  ROSAT has discovered a new group of isolated neutron stars characterized by
soft black-body like spectra (kT ~ 50-120 eV), apparent absence of radio
emission and no association with supernovae remnants. So far only six such
sources are known. A small fraction of these stars exhibit X-ray pulsations
with relatively long periods of the order of 10 sec. Two very different
mechanisms may be envisaged to explain their properties. The neutron stars may
be old and re-heated by accretion from the ISM in which case their population
properties could provide information on past stellar formation and secular
magnetic field decay. Alternatively, this group may at least partly be made of
relatively young cooling neutron stars possibly descendant from magnetars. We
review the last observational results and show how they can shed light on the
evolutionary path of these new objects within the whole class of isolated
neutron stars.

</DOC>
<DOC>
<DOCNO> 99649 </DOCNO>
The structure of corings: Induction functors, Maschke-type theorem, and


  Given a ring $A$ and an $A$-coring $\cC$ we study when the forgetful functor
from the category of right $\cC$-comodules to the category of right $A$-modules
and its right adjoint $-\otimes_A\cC$ are separable. We then proceed to study
when the induction functor $-\otimes_A\cC$ is also the left adjoint of the
forgetful functor. This question is closely related to the problem when $A\to
{}_A{\rm Hom}(\cC,A)$ is a Frobenius extension.
 We introduce the notion of a Galois coring and analyse when the tensor functor
over the subring of $A$ fixed under the coaction of $\cC$ is an equivalence. We
also comment on possible dualisation of the notion of a coring.

</DOC>
<DOC>
<DOCNO> 71760 </DOCNO>
Cosmological Solutions of Supergravity in Singular Spaces


  We study brane-world solutions of five-dimensional supergravity in singular
spaces. We exhibit a self-tuned four-dimensional cosmological constant when
five-dimensional supergravity is broken by an arbitrary tension on the
brane-world. The brane-world metric is of the FRW type corresponding to a
cosmological constant $\Omega_{\Lambda}={5/7}$ and an equation of state
$\omega=-{5/7}$ which are consistent with experiment.

</DOC>
<DOC>
<DOCNO> 119644 </DOCNO>
Monitoring All Sky for Variability


  A few percent of all stars are variable, yet over 90% of variables brighter
than 12 magnitude have not been discovered yet. There is a need for an all sky
search and for the early detection of any unexpected events: optical flashes
from gamma-ray bursts, novae, dwarf novae, supernovae, `killer asteroids'. The
ongoing projects like ROTSE, ASAS, TASS, and others, using instruments with
just 4 inch aperture, have already discovered thousands of new variable stars,
a flash from an explosion at a cosmological distance, and the first partial
eclipse of a nearby star by its Jupiter like planet. About one million
variables may be discovered with such small instruments, and many more with
larger telescopes. The critical elements are software and full automation of
the hardware. A complete census of the brightest eclipsing binaries is needed
to select objects for a robust empirical calibration of the the accurate
distance determination to the Magellanic Clouds, the first step towards the
Hubble constant. An archive to be generated by a large number of small
instruments will be very valuable for data mining projects. The real time
alerts will provide great targets of opportunity for the follow-up observations
with the largest telescopes.

</DOC>
<DOC>
<DOCNO> 70502 </DOCNO>
The Electroweak Interactions as a Confinement Phenomenon


  We consider a model for the electroweak interactions based on the assumption
that physical particles are singlets under the gauge group SU(2). The concept
of complementarity explains why the standard model works with such an
extraordinary precision although the fermions and bosons of the model can be
viewed as composite objects of some more fundamental fermions and bosons. We
study the incorporation of QED in the model. Furthermore we consider possible
deviations from the standard model at very high energies, e.g. excited states
of the weak bosons.

</DOC>
<DOC>
<DOCNO> 8363 </DOCNO>
Disorder Induced Transitions in Layered Coulomb Gases and


  A 3D layered system of charges with logarithmic interaction parallel to the
layers and random dipoles is studied via a novel variational method and an
energy rationale which reproduce the known phase diagram for a single layer.
Increasing interlayer coupling leads to successive transitions in which charge
rods correlated in N>1 neighboring layers are nucleated by weaker disorder. For
layered superconductors in the limit of only magnetic interlayer coupling, the
method predicts and locates a disorder-induced defect-unbinding transition in
the flux lattice. While N=1 charges dominate there, N>1 disorder induced defect
rods are predicted for multi-layer superconductors.

</DOC>
<DOC>
<DOCNO> 11186 </DOCNO>
Mean Field Theory of Spherical Gravitating Systems


  Important gaps remain in our understanding of the thermodynamics and
statistical physics of self-gravitating systems. Using mean field theory, here
we investigate the equilibrium properties of several spherically symmetric
model systems confined in a finite domain consisting of either point masses, or
rotating mass shells of different dimension. We establish a direct connection
between the spherically symmetric equilibrium states of a self-gravitating
point mass system and a shell model of dimension 3. We construct the
equilibrium density functions by maximizing the entropy subject to the usual
constraints of normalization and energy, but we also take into account the
constraint on the sum of the squares of the individual angular momenta, which
is also an integral of motion for these symmetric systems. Two new statistical
ensembles are introduced which incorporate the additional constraint. They are
used to investigate the possible occurrence of a phase transition as the
defining parameters for each ensemble are altered.

</DOC>
<DOC>
<DOCNO> 178547 </DOCNO>
Nuclear structure from random interactions


  Low-lying states in nuclei are investigated using an ensemble of random
interactions. Both in the nuclear shell model and in the interacting boson
model we find a dominance of $J^P=0^+$ ground states. It is shown that this
feature is not due to time reversal symmetry. In the shell model, evidence is
found for the occurrence of pairing properties, and in the interacting boson
model for both vibrational and rotational band structures. Our results suggest
that these features represent general and robust properties of the model space,
and do not depend on details of the interactions.

</DOC>
<DOC>
<DOCNO> 9032 </DOCNO>
Decrumpling membranes by quantum effects


  The phase diagram of an incompressible fluid membrane subject to quantum and
thermal fluctuations is calculated exactly in a large number of dimensions of
configuration space. At zero temperature, a crumpling transition is found at a
critical bending rigidity $1/\alpha_{\rm c}$. For membranes of fixed lateral
size, a crumpling transition occurs at nonzero temperatures in an auxiliary
mean field approximation. As the lateral size L of the membrane becomes large,
the flat regime shrinks with $1/\ln L$.

</DOC>
<DOC>
<DOCNO> 7875 </DOCNO>
Triplet forces between star polymers


  We analyze the effective triplet interactions between the centers of star
polymers in a good solvent. Using an analytical short distance expansion
inspired by scaling theory, we deduce that the triplet part of the three-star
force is attractive but only 11% of the pairwise part even for a close approach
of three star polymers. We have also performed extensive computer simulations
for different arm numbers to extract the effective triplet force. The
simulation data show good correspondence with the theoretical predictions. Our
results justify the effective pair potential picture even beyond the star
polymer overlap concentration.

</DOC>
<DOC>
<DOCNO> 8896 </DOCNO>
Role of free energy landscape in the dynamics of mean field glassy


  In this paper we expose the results of our recent work on the dynamical TAP
approach to mean field glassy systems. Our aim is to clarify the connection
between free energy landscape and out of equilibrium dynamics in solvable
models. Frequently qualitative explanations of glassy behaviour are based on
the ``Free Energy Landscape Paradigm''. If its relevance for equilibrium
properties is clear, the relationship between free energy landscape and out of
equilibrium dynamics is not well understood yet. In this paper we clarify this
relationship for the class of spin glass models which reproduce
phenomenologically some features of structural glasses. The method we use is a
generalisation to dynamics of the Thouless, Anderson and Palmer approach to
thermodynamics of mean field spin glasses. Within this framework we show to
what extent the dynamics can be represented as an evolution in the free energy
landscape. In particular the relationship between the long-time dynamics and
the local properties of the free energy landscape shows up explicitly using
this approach.

</DOC>
<DOC>
<DOCNO> 70568 </DOCNO>
Superconducting Cosmic String with Propagating Torsion


  We show that it is possible to construct a consistent model describing a
current-carrying cosmic string endowed with torsion. The torsion contribution
to the gravitational force and geodesics of a test-particle moving around the
SCCS are analyzed. In particular, we point out two interesting astrophysical
phenomena in which the higher magnitude force we derived may play a critical
role: the dynamics of compact objects orbiting the torsioned SCCS and accretion
of matter onto it. The deficit angle associated to the SCCS can be obtained and
compared with data from the Cosmic Background Explorer (COBE) satellite. We
also derived a value for the torsion contribution to matter density
fluctuations in the early Universe.

</DOC>
<DOC>
<DOCNO> 151261 </DOCNO>
Scale Vs. Conformal Invariance in the AdS/CFT Correspondence


  We present two examples of non-trivial field theories which are scale
invariant, but not conformally invariant. This is done by placing certain field
theories, which are conformally invariant in flat space, onto curved
backgrounds of a specific type. We define this using the AdS/CFT
correspondence, which relates the physics of gravity in asymptotically Anti-de
Sitter (AdS) spacetimes to that of a conformal field theory (CFT) in one
dimension fewer. The AdS rotating (Kerr) black holes in five and seven
dimensions provide us with the examples, since by the correspondence we are
able to define and compute the action and stress tensor of four and six
dimensional field theories residing on rotating Einstein universes, using the
``boundary counterterm'' method. The rotation breaks conformal but not scale
invariance. The AdS/CFT framework is therefore a natural arena for generating
such examples of non-trivial scale invariant theories which are not conformally
invariant.

</DOC>
<DOC>
<DOCNO> 10637 </DOCNO>
Unexpected properties of the first excited state of non-bipartite


  Systematic properties of the first excited state are presented for various
ring sizes and spin quantum numbers which are only partly covered by the
theorem of Lieb, Schultz and Mattis. For odd ring sizes the first excited
energy eigenvalue shows unexpected degeneracy and related shift quantum
numbers. As a byproduct the ground state energy as well as the energy of the
first excited state of infinite chains are calculated by extrapolating the
properties of only a few, finite, antiferromagnetically coupled Heisenberg
rings using the powerful Levin sequence acceleration method.

</DOC>
<DOC>
<DOCNO> 102051 </DOCNO>
On the existence of polynomial first integrals of quadratic homogeneous


  We consider systems of ordinary differential equations with quadratic
homogeneous right hand side. We give a new simple proof of a result already
obtained in [8,10] which gives the necessary conditions for the existence of
polynomial first integrals. The necessary conditions for the existence of a
polynomial symmetry field are given. It is proved that an arbitrary homogeneous
first integral of a given degree is a linear combination of a fixed set of
polynomials.

</DOC>
<DOC>
<DOCNO> 151049 </DOCNO>
Inertial Force, Equivalence Principle and Quantum Mechanics


  On the basis of a manifestly covariant formalism of non-relativistic quantum
mechanics in general coordinate systems, proposed by us recently, we derive
general expressions for inertial forces. The results enable us further to
discuss, and to explain the validity of, the equivalence principle in
non-relativistic quantum mechanics.

</DOC>
<DOC>
<DOCNO> 40300 </DOCNO>
Quasi-coherent interaction of protons with Si28 at Tp=1GeV


  The total, elastic and inelastic cross-sections for quasi-coherent
interactions of protons with Si28 have been measured using hadron-gamma
coincidence method at the energy 1 GeV. The limits for the existence of
long-lived excited states of the Si28 nucleus have been obtained in the range
of energies from 0 to 0.8 GeV.

</DOC>
<DOC>
<DOCNO> 72074 </DOCNO>
CP-violation in 3- and 4-family at the Neutrino Factory


  The leptonic CP-violating phase $\delta$ can be measured with a Neutrino
Factory with $2 \times 10^{20} $ useful muons per year, if the solar neutrino
problem is solved by the LMA-MSW solution, with $\Delta m_{12}^2 \ge 2 \times
10^{-5}$ eV$^2$ (in this analysis a 40 kT magnetized iron detector is
considered, taking into account its efficiencies and backgrounds). If LSND is
confirmed, CP-violating phenomena in four-family scenarios can be most easily
addressed with a small 1 kT detector at $L = \cal O$(10) km (no detailed
analysis of the detector efficiencies and backgrounds has been performed in
this case).

</DOC>
<DOC>
<DOCNO> 122053 </DOCNO>
Testing Fundamental Physics with High-Energy Cosmic Rays


  Cosmic rays may provide opportunities for probing fundamental physics. For
example, ultra-high-energy cosmic rays might originate from the decays of
metastable heavy particles, and astrophysical gamma rays can be used to test
models of quantum gravity. Both scenarios offer ways to avoid the GZK cut-off.

</DOC>
<DOC>
<DOCNO> 13455 </DOCNO>
Symmetrized mean-field description of magnetic instabilities in


  We present a novel and convenient mean-field method, and apply it to study
the metallic/antiferromagnetic interface of k-(BEDT-TTF)_2Cu[N(CN)]_2 Y organic
superconductors (BEDT_TTF is bis-ethylen-dithio-tetrathiafulvalene, Y=Cl, Br).
The method, which fully exploits the crystal symmetry, allows one to obtain the
mean-field solution of the 2D Hubbard model for very large lattices, up to
6x10^5 sites, yielding a reliable description of the phase boundary in a wide
region of the parameter space. The metal/antiferromagnet transtion appears to
be second order, except for a narrow region of the parameter space, where the
transition is very sharp and possibly first order. The cohexistence of metallic
and antiferromagnetic properties is only observed for the transient state in
the case of smooth second order transitions. The relevance of the present
resaults to the complex experimental behavior of centrosymmetric k-phase
BEDT-TTF salts is discussed.

</DOC>
<DOC>
<DOCNO> 85215 </DOCNO>
On the solutions of the Cartan equation in Metric Affine Gravity


  In the Tucker-Wang approach to Metric Affine gravity we review some
particular solutions of the Cartan equation for the non-riemannian part of the
connection. As application we show how a quite general non Riemannian model
gives a Proca type equation for the trace of the nonmetricity 1-forms Q.

</DOC>
<DOC>
<DOCNO> 117488 </DOCNO>
Millisecond Oscillations in X-Ray Binaries


  The first millisecond X-ray variability phenomena from accreting compact
objects have recently been discovered with the Rossi X-ray Timing Explorer.
Three new phenomena are observed from low-mass X-ray binaries containing
low-magnetic-field neutron stars: millisecond pulsations, burst oscillations
and kiloHertz quasi-periodic oscillations. Models for these new phenomena
involve the neutron star spin, and orbital motion closely around the neutron
star and rely explicitly on our understanding of strong gravity and dense
matter. I review the observations of these new neutron-star phenomena and
possibly related ones in black-hole candidates, and describe the attempts to
use them to perform measurements of fundamental physical interest in these
systems.

</DOC>
<DOC>
<DOCNO> 123070 </DOCNO>
Physical Parameter Eclipse Mapping


  The tomographic method "Physical Parameter Eclipse Mapping" is a tool to
reconstruct spatial distributions of physical parameters (like temperatures and
surface densities) in accretion discs of cataclysmic variables. After
summarizing the method, we apply it to multi-colour eclipse light curves of
various dwarf novae and nova-likes like VZ Scl, IP Peg in outburst, UU Aqr,
V2051 Oph and HT Cas in order to derive the temperatures (and surface
densities) in the disc, the white dwarf temperature, the disc size, the
effective temperatures and the viscosities. The results allows us to establish
or refine a physical model for the accretion disc. Our maps of HT Cas and V2051
Oph, for example, indicate that the (quiescent) disc must be structured into a
cool, optically thick inner disc sandwiched by hot, optically thin
chromospheres. In addition, the disc of HT Cas must be patchy with a covering
factor of about 40% caused by magnetic activity in the disc.

</DOC>
<DOC>
<DOCNO> 70505 </DOCNO>
Exploring the structure of a possible light scalar nonet


  We first review the work of the Syracuse group, which uses an effective
chiral Lagrangian approach, on meson-meson scattering. An illustration
providing evidence for the existence of a strange scalar resonance of mass
around 900 MeV is given. An attempt to fit this $\kappa (900)$ together with a
similarly obtained $\sigma (560)$ and the well known $a_0(980)$ and $f_0(980)$
into a nonet pattern suggests that the underlying structure is closer to a dual
quark-dual antiquark than to a quark-antiquark. A possible mechanism to explain
a next higher-in mass scalar meson nonet is also discussed. This involves
mixing between $q{\bar q}$ and $qq{\bar q} {\bar q}$ states.

</DOC>
<DOC>
<DOCNO> 70099 </DOCNO>
Combining QCD Matrix Elements at Next-to-Leading Order with Parton


  We present a method to combine next-to-leading order (NLO) matrix elements in
QCD with leading logarithmic parton showers by applying a suitably modified
version of the phase-space-slicing method. The method consists of subsuming the
NLO corrections into a scale-dependent phase-space-slicing parameter, which is
then automatically adjusted to cut out the leading order, virtual, soft and
collinear contributions in the matrix element calculation. In this way a
positive NLO weight is obtained, which can be redistributed by a parton shower
algortihm. As an example, we display the method for single-jet inclusive cross
sections at O(alpha_s) in electroproduction. We numerically compare the
modified version of the phase-space-slicing method with the standard approach
and find very good agreement on the percent level.

</DOC>
<DOC>
<DOCNO> 9634 </DOCNO>
Low-frequency spin dynamics in the orthorombic phase of La_2CuO_4


  An effective field theory is derived that describes the low-frequency spin
dynamics in the low-temperature orthorombic phase of La_2CuO_4. Restricted to a
single CuO_2 layer the effective theory is a simple generalization of the
relativistic nonlinear sigma model to include all spin interactions allowed by
symmetry. Incorporating a weak interlayer interaction leads to two coupled
nonlinear sigma models which provide an efficient description of the complete
bilayer dynamics. Particular attention is paid to the weak-ferromagnetic and
spin-flop transitions induced by external magnetic fields. The main features of
the observed (covert) weak ferromagnetism are thus accounted for in a
straightforward manner but some of the finer theoretical predictions would
require further experimental investigation. The derived framework is also
suitable for the study of the structure and dynamics of magnetic domains in
undoped La_2CuO_4.

</DOC>
<DOC>
<DOCNO> 101968 </DOCNO>
Monoidal structure of the category of u$_q^+$-modules


  We study the finite dimensional modules on the half-quantum group u_q^+ at a
root of unity q, whose action can be extended to u_q (quotient of the quantized
enveloping algebra of sl_2). We derive decomposition formulas of the tensor
product of indecomposable u_q^+-modules, which includes the cases of the
universal and the quantized universal enveloping algebra of sl_2 for q not a
root of unity. We also prove that simple modules on u_q correspond exactly to
the extendable non projective u_q^+-modules. We thus establish decomposition
formulas for the tensor product of simple u_q-modules.

</DOC>
<DOC>
<DOCNO> 117086 </DOCNO>
The Alpha Constant from Relativistic Groups


  The value of the alpha constant, known to be equal to an algebraic expression
in terms of pi and entire numbers related to certain group volumes, is derived
from the relativistic structure group of a geometric unified theory, its
subgroups and corresponding symmetric space quotients.

</DOC>
<DOC>
<DOCNO> 40092 </DOCNO>
The Measurement of Azimuthal Asymmetries in Deep Inelastic Scattering


  The distribution of the azimuthal angle for the charged hadrons has been
studied in the hadronic centre-of-mass system for neutral current deep
inelastic positron-proton scattering at HERA. Measurements of the dependence of
the moments of this distribution on the transverse momenta of the charged
hadrons are presented. Asymmetries that can be unambiguously attributed to
perturbative QCD processes have been observed for the first time.

</DOC>
<DOC>
<DOCNO> 170408 </DOCNO>
Nonequilibrium-current-induced corrections to the


  Electron gas in a wire connected to two terminals with potential drop is
studied with the Schwinger-Keldysh formalism. Recent studies, where the current
is enforced to flow with a Lagrange-multiplier term, demonstrated that the
current enhances the one-particle-correlation function. We report that in our
model, such enhancement is not guaranteed to occur, but conditional both on the
potential drop and the positions where we observe the correlation function.
That is, under a certain condition, spatially modulated pattern is formed in
the wire owing to the nonequilibrium current.

</DOC>
<DOC>
<DOCNO> 120521 </DOCNO>
Evidence for Supermassive Black Holes in Active Galactic Nuclei from


  Emission-line variability data for Seyfert 1 galaxies provide strong evidence
for the existence of supermassive black holes in the nuclei of these galaxies,
and that the line-emitting gas is moving in the gravitational potential of that
black hole. The time-delayed response of the emission lines to continuum
variations is used to infer the size of the line-emitting region, which is then
combined with measurements of the Doppler widths of the variable line
components to estimate a virial mass. In the case of the best-studied galaxy,
NGC 5548, various emission lines spanning an order of magnitude in distance
from the central source show the expected velocity proportional to inverse
square root of the distance correlation between distance and line width, and
are thus consistent with a single value for the mass. Two other Seyfert
galaxies, NGC 7469 and 3C 390.3, show a similar relationship. We compute the
ratio of luminosity to mass for these three objects and the narrow-line Seyfert
1 galaxy NGC 4051 and find that that the gravitational force on the
line-emitting gas is much stronger than radiation pressure. These results
strongly support the paradigm of gravitationally bound broad emission-line
region clouds.

</DOC>
<DOC>
<DOCNO> 71331 </DOCNO>
Hydrogen Atom Spectrum and the Lamb Shift in Noncommutative QED


  We have calculated the energy levels of the hydrogen atom and as well the
Lamb shift within the noncommutative quantum electrodynamics theory. The
results show deviations from the usual QED both on the classical and on the
quantum levels. On both levels, the deviations depend on the parameter of
space/space noncommutativity.

</DOC>
<DOC>
<DOCNO> 40494 </DOCNO>
"photon+Jet" events rate estimation for gluon distribution determination


  It is shown that "photon+Jet" events, being collected at LHC, would provide
us with the data sufficient for an extraction of gluon distribution function in
a proton using valence and s quark distributions measured in the same
experiment with another physical proces A new region of 10^{-4}< x < 10^{-1}
with 1.6x10^3< Q^2<10^5 ~(GeV/c)^2 can be covered. The rates of g c-> photon
+Jet events are also given.

</DOC>
<DOC>
<DOCNO> 69415 </DOCNO>
Note on tree-level unitarity in the General Two Higgs Doublet Model


  Tree-level unitarity constraints on the masses of the Higgs bosons in the
general Two Higgs Doublet Model (THDM) are studied. We first consider the case
where the Higgs potential is invariant under a discrete symmetry
transformation, and derive strong constraints on the mass of the lightest
CP-even Higgs boson ($M_h$) as a function of $\tan\beta$. We then show that the
inclusion of the discrete symmetry breaking term weakens the mass bounds
considerably. It is suggested that a measurement of $M_h$ and $\tan\beta$ may
enable discrimination between the two Higgs potentials.

</DOC>
<DOC>
<DOCNO> 12436 </DOCNO>
Nonequilibrium effects in superconducting necks of nanoscopic dimensions


  We have fabricated superconducting connecting necks of Pb with a scanning
tunneling microscope (STM) and studied their properties under magnetic fields
near the transition to the resistive state. A striking phenomenology is found
with two well defined conduction regimes as a function of the magnetic field.
We discuss the possible origin of this behavior in terms of the interplay
between the field dependence of the quasiparticle charge imbalance length
$\Lambda_{Q*}$ and the length of the neck which is superconducting under field.

</DOC>
<DOC>
<DOCNO> 101875 </DOCNO>
Recent progress on the Kakeya conjecture


  The purpose of this article is to survey the developments on the Kakeya
problem in recent years, concentrating on the period after the excellent 1999
survey of Wolff, and including some recent work by the authors. We will focus
on the standard Kakeya problem for line segments and not discuss other
important variants (such as Kakeya estimates for circles, light rays, or
$k$-planes).

</DOC>
<DOC>
<DOCNO> 84454 </DOCNO>
Holographic Bound From Second Law of Thermodynamics


  A necessary condition for the validity of the holographic principle is the
holographic bound: the entropy of a system is bounded from above by a quarter
of the area of a circumscribing surface measured in Planck areas. This bound
cannot be derived at present from consensus fundamental theory. We show with
suitable {\it gedanken} experiments that the holographic bound follows from the
generalized second law of thermodynamics for both generic weakly gravitating
isolated systems and for isolated, quiescent and nonrotating strongly
gravitating configurations well above Planck mass. These results justify
Susskind's early claim that the holographic bound can be gotten from the second
law.

</DOC>
<DOC>
<DOCNO> 101364 </DOCNO>
A Bayesian approach to source separation


  Source separation is one of the signal processing's main emerging domain.
Many techniques such as maximum likelihood (ML), Infomax, cumulant matching,
estimating function, etc. have been used to address this difficult problem.
Unfortunately, up to now, many of these methods could not account completely
for noise on the data, for different number of sources and sensors, for lack of
spatial independence and for time correlation of the sources. Recently, the
Bayesian approach has been used to push farther these limitations of the
conventional methods. This paper proposes a unifying approach to source
separation based on the Bayesian estimation. We first show that this approach
gives the possibility to explain easily the major known techniques in sources
separation as special cases. Then we propose new methods based on maximum a
posteriori (MAP) estimation, either to estimate directly the sources, or the
mixing matrices or even both.

</DOC>
<DOC>
<DOCNO> 102210 </DOCNO>
Homogenization of Periodic Multi-Dimensional Structures II: The Linearly


  In this paper we study the asymptotic behaviour via Gamma-convergence of some
integral functionals which model some multi-dimensional structures and depend
explicitly on the linearized strain tensor. The functionals are defined in
particular classes of functions with bounded deformation while the limit
problem is set in the usual framework of Sobolev spaces or BD. We also
construct an example of such functionals showing that under some special
assumptions we can have non local effects.

</DOC>
<DOC>
<DOCNO> 151302 </DOCNO>
Integrable and Conformal Boundary Conditions for sl(2) A-D-E Lattice


  Integrable boundary conditions are studied for critical A-D-E and general
graph-based lattice models of statistical mechanics. In particular, using
techniques associated with the Temperley-Lieb algebra and fusion, a set of
boundary Boltzmann weights which satisfies the boundary Yang-Baxter equation is
obtained for each boundary condition. When appropriately specialized, these
boundary weights, each of which depends on three spins, decompose into more
natural two-spin edge weights. The specialized boundary conditions for the
A-D-E cases are naturally in one-to-one correspondence with the conformal
boundary conditions of sl(2) unitary minimal conformal field theories.
Supported by this and further evidence, we conclude that, in the continuum
scaling limit, the integrable boundary conditions provide realizations of the
complete set of conformal boundary conditions in the corresponding field
theories.

</DOC>
<DOC>
<DOCNO> 116625 </DOCNO>
On the Arbitrary Choice Regarding which Inertial Reference Frame is


  Einstein's argument on the relativity of simultaneity itself is the first
result of the special theory of relativity. The nature of this result is
explored, and implications of this result for the structure and functioning of
the physical world found in the special theory are discussed.

</DOC>
<DOC>
<DOCNO> 11250 </DOCNO>
Dynamics of short polymer chains in solution


  We present numerical and analytical results describing the effect of
hydrodynamic interactions on the dynamics of a short polymer chain in solution.
A molecular dynamics algorithm for the polymer is coupled to a direct
simulation Monte Carlo algorithm for the solvent. We give an explicit
expression for the velocity autocorrelation function of the centre of mass of
the polymer which agrees well with numerical results if Brownian dynamics,
hydrodynamic correlations and sound wave scattering are included.

</DOC>
<DOC>
<DOCNO> 99282 </DOCNO>
Majorant Series


  This article discusses questions in one and several complex variables about
the size of the sum of the moduli of the terms of the series expansion of a
bounded holomorphic function. Although the article is partly expository, it
also includes some previously unpublished results with complete proofs.
  The article is based on a lecture at the third Korean several complex
variables symposium held at the Global Analysis Research Center at Seoul
National University in December 1998.

</DOC>
<DOC>
<DOCNO> 40630 </DOCNO>
Moments of the charged-particle multiplicity distribution in Z decays at


  The charged-particle multiplicity distribution and its moments have been
measured, for all hadronic as well as for light-quark and b-quark events in
e+e- collisions at the Z mass. The Hq moments derived from the charged-particle
multiplicity distribution are known to exhibit quasi-oscillations when plotted
versus the order of the moment. This behavior is predicted by the NNLLA of
perturbative QCD for the parton level and, under the assumption of LPHD, also
for the hadron level. Using the jet multiplicity distributions in order to vary
the dependence on the LPHD hypothesis, we find, however, that at our energy the
oscillations only appear for non-perturbative scales. In the absence of
confirmation of pQCD, we investigate a more phenomenological answer in the
possibility that the features seen in the Hq behavior could be due to the fact
that the charged-particle multiplicity derives from a superposition of final
states related to the topology of the events. Therefore, the analysis is
repeated using charged-particle multiplicity distributions originating from
2-jet and 3-jet events for the full, light- and b-quark samples.

</DOC>
<DOC>
<DOCNO> 120914 </DOCNO>
The 1997 periastron passage of the binary pulsar PSR B1259-63


  We report here on multifrequency radio observations of the pulsed emission
from PSR B1259-63 around the time of the closest approach to its B2e companion
star. There was a general increase in the pulsar's dispersion measure and
scatter broadening, and a decrease in the flux density towards periastron
although changes in these parameters were seen on timescales as short as
minutes. The pulsed emission disappeared 16 days prior to periastron and
remained undetectable until 16 days after periastron.
  The observations are used to determine the parameters of the wind from the Be
star. We show that a simple model, in which the wind density varies with radius
as r^-2, provides a good fit to the data. The wind is clumpy with size scales
<= 10^10 cm, densities of 10^6 cm^-3 and a velocity of 2000 km/s at a distance
of 20 - 50 stellar radii. We find a correlation between dispersion measure
variations and the pulse scattering times, suggesting that the same electrons
are responsible for both effects.

</DOC>
<DOC>
<DOCNO> 116358 </DOCNO>
Noncanonical quantum optics


  Modification of the right-hand-side of canonical commutation relations (CCR)
naturally occurs if one considers a harmonic oscillator with indefinite
frequency. Quantization of electromagnetic field by means of such a non-CCR
algebra naturally removes the infinite energy of vacuum but still results in a
theory which is very similar to quantum electrodynamics. An analysis of
perturbation theory shows that the non-canonical theory has an automatically
built-in cut-off but requires charge/mass renormalization already at the
nonrelativistic level. A simple rule allowing to compare perturbative
predictions of canonical and non-canonical theories is given. The notion of a
unique vacuum state is replaced by a set of different vacua. Multi-photon
states are defined in the standard way but depend on the choice of vacuum.
Making a simplified choice of the vacuum state we estimate corrections to
atomic lifetimes, probabilities of multiphoton spontaneous and stimulated
emission, and the Planck law. The results are practically identical to the
standard ones. Two different candidates for a free-field Hamiltonian are
compared.

</DOC>
<DOC>
<DOCNO> 11592 </DOCNO>
Density of states and electron concentration of double heterojunctions


  We calculate the electronic states of
Al$_x$Ga$_{1-x}$As/GaAs/Al$_x$Ga$_{1-x}$As double heterojunctions subjected to
a magnetic field parallel to the quasi two-dimensional electron gas. We study
the energy dispersion curves, the density of states, the electron concentration
and the distribution of the electrons in the subbands. The parallel magnetic
field induces severe changes in the density of states, which are of crucial
importance for the explanation of the magnetoconductivity in these structures.
However, to our knowledge, there is no systematic study of the density of
states under these circumstances. We attempt a contribution in this direction.
For symmetric heterostructures, the depopulation of the higher subbands, the
transition from a single to a bilayer electron system and the domination of the
bulk Landau levels in the centre the wide quantum well, as the magnetic field
is continuously increased, are presented in the ``energy dispersion picture''
as well as in the ``electron concentration picture'' and in the ``density of
states picture''.

</DOC>
<DOC>
<DOCNO> 13163 </DOCNO>
Quantum Vortex in a Vectorial Bose-Einstein Condensate


  Quantum vortices in the multi-component Bose-Einstein condensation (BEC) are
investigated theoretically. It is found that three kinds of the vortex
configurations are possible and their physical properties are discussed in
details, including the density distribution and the spin texture. By using the
Bogoliubov theory extended to the three component BEC, the collective modes for
these vortices are evaluated. The local vortex stability for these vortices are
examined in light of the existence of the negative eigenvalue, yielding a
narrow magnetization window for the local intrinsic stable region where the
multi-components work together to stabilize a vortex in a self-organized way.

</DOC>
<DOC>
<DOCNO> 120295 </DOCNO>
Formation of the Neutron Donor C13 in AGB Stars by Overshoot and


  (abridged) Observations clearly show that low-mass AGB stars can provide a
nucleosynthesis site of the s-process. Recent stellar evolution models indicate
that radiative burning of C13 between thermal pulses in low-mass AGB stars may
indeed provide the needed neutrons. Some mixing between the proton-rich
envelope and the carbon-rich core may lead to the production of C13. However,
the responsible physical mechanism is not yet unambiguously identified. We
present stellar model calculations with overshoot and rotation. Overshoot, with
a time-dependent and exponentially decaying efficiency, leads to a partial
mixture of protons and C12 during the third dredge-up. According to the
depth-dependent ratio of protons and C12, a small C13-pocket forms underneath a
N14-rich layer. Overshoot does not allow for any mixing during the interpulse
phase. Rotation introduces mixing driven by large angular velocity gradients
which form at the envelope-core interface in AGB stars, in particular after a
thermal pulse. This leads to partial mixing after a pulse, as in the case of
overshoot. However, rotation continues to mix the region of the C13-pocket with
a diffusion coefficient of log D ~ 2...3 [cm**2 / s]. This does not only spread
the C13-pocket, but also the more massive N14-rich layer, and finally leads to
mixture of both layers. By the time when the temperature there has risen to
about 9*10E7K and neutron production sets in, the N14 abundance exceeds the C13
abundance by a factor of 5...10. We analyze the role of N14 as a neutron poison
by considering the recycling of neutrons via N14(n,p)C14 and
C12(p,gamma)N13(beta+)C13 qualitatively. We find that as long as X(N14) <<
X(C12), the s-process will still be possible to occur under radiative
conditions.

</DOC>
<DOC>
<DOCNO> 120981 </DOCNO>
A Deep Multicolor Survey. VI. Near-Infrared Observations, Selection


  I present near-infrared J (1.25um), H (1.65um), and K (2.2um) imaging
observations of 185 square arcminutes in 21 high galactic latitude fields.
These observations reach limiting magnitudes of J ~ 21 mag, H ~ 20 mag and K ~
18.5 mag. The detection efficiency, photometric accuracy and selection biases
as a function of integrated object brightness, size, and profile shape are
quantified in detail. I evaluate several popular methods for measuring the
integrated light of faint galaxies and show that only aperture magnitudes
provide an unbiased measure of the integrated light that is independent of
apparent magnitude. These J, H, and K counts and near-infrared colors are in
best agreement with passive galaxy formation models with at most a small amount
of merging (for Omega_M = 0.3, Omega_Lambda = 0.7).

</DOC>
<DOC>
<DOCNO> 85606 </DOCNO>
Gravitomagnetic Barnett Effect


  Using the linearized theory of general relativity, the gravitomagnetic
analogue of the Barnett effect is derived. Further theoretical and experimental
investigation is recommended, due to the expected macroscopic values of the
gravitomagnetic field involved in this effect, and to the constraints which
would appear on quantum theories of gravity, currently under development, in
case of non detection of the predicted phenomena.

</DOC>
<DOC>
<DOCNO> 67672 </DOCNO>
Hadronic Physics


  I review the novel results and developments presented at the Third Workshop
on Physics and Detectors for DA$\Phi$NE that deal with hadronic physics. Topics
discussed include: the scalar quark condensate, kaon decays, the sector of
scalar and vector mesons, kaon-nucleon scattering, pion- and kaon-nucleon sigma
terms, and strange nuclear physics.

</DOC>
<DOC>
<DOCNO> 70508 </DOCNO>
Photon and Pion Production at High $p_T$


  We present a study of high-$p_T$ photon and pion production in hadronic
interactions, focusing on a comparison of the yields with expectations from
next-to-leading order perturbative QCD (NLO pQCD). We examine the impact of
phenomenological models of $k_T$ smearing (which approximate effects of
additional soft-gluon emission) on absolute predictions for photon and pion
production and their ratio.

</DOC>
<DOC>
<DOCNO> 99370 </DOCNO>
A remark on the equivalence of isokinetic and isoenergetic thermostats


  The Gaussian isokinetic and isoenergetic thermostats of Hoover and Evans are
formally equivalent as remarked by Gallavotti, Rondoni and Cohen. But outside
of equilibrium the fluctuations are uncontrolled and might break the
equivalence. We show that equivalence is ensured if we consider an infinite
system assumed to be ergodic under space translations.

</DOC>
<DOC>
<DOCNO> 178946 </DOCNO>
Quantum Calculation of Dipole Excitation in Fusion Reaction


  The excitation of the giant dipole resonance by fusion is studied with N/Z
asymmetry in the entrance channel. the TDHF solution exhibits a strong dipole
vibration which can be associated with a giant vibration along the main axis of
a fluctuating prolate shape. The consequences on the gamma-ray emission from
hot compound nuclei are discussed.

</DOC>
<DOC>
<DOCNO> 84141 </DOCNO>
Divergence of the Quantum Stress Tensor on the Cauchy Horizon in 2-d


  We prove that the quantum stress tensor for a massless scalar field in two
dimensional non-selfsimilar Tolman Bondi dust collapse and Vaidya radiation
collapse models diverges on the Cauchy horizon, if the latter exists. The two
dimensional model is obtained by suppressing angular co-ordinates in the
corresponding four dimensional spherical model.

</DOC>
<DOC>
<DOCNO> 120491 </DOCNO>
Photometric Redshifts and Gravitational Telescopes


  We review the use of photometric redshifts in the particular context of
Gravitational Telescopes. We discuss on the possible application of such a
technique to the study of both the faint population of distant sources and the
properties of cluster lenses. Photometric reshifts could be used to derive the
redshift distribution and properties of a very faint subsample of high-z lensed
galaxies, otherwise out of reach. Concerning the mass distribution in lensing
clusters, photometric reshifts are strongly needed to scale the mass in weak
lensing analysis, and to characterize the lensing structure.

</DOC>
<DOC>
<DOCNO> 11647 </DOCNO>
Novel Phases and Reentrant Melting of Two Dimensional Colloidal Crystals


  We investigate two-dimensional (2d) melting in the presence of a
one-dimensional (1d) periodic potential as, for example, realized in recent
experiments on 2d colloids subjected to two interfering laser beams. The
topology of the phase diagram is found to depend primarily on two factors: the
relative orientation of the 2d crystal and the periodic potential troughs,
which select a set of Bragg planes running parallel to the troughs, and the
commensurability ratio p= a'/d of the spacing a' between these Bragg planes to
the period d of the periodic potential. The complexity of the phase diagram
increases with the magnitude of the commensurabilty ratio p. Rich phase
diagram, with ``modulated liquid'', ``floating'' and ``locked floating'' solid
and smectic phases are found. Phase transitions between these phases fall into
two broad universality classes, roughening and melting, driven by the
proliferation of discommensuration walls and dislocations, respectively. We
discuss correlation functions and the static structure factor in these phases
and make detailed predictions of the universal features close to the phase
boundaries. We predict that for charged systems with highly screened
short-range interactions these melting transitions are generically reentrant as
a function of the strength of the periodic potential, prediction that is in
accord with recent 2d colloid experiments. Implications of our results for
future experiments are also discussed.

</DOC>
<DOC>
<DOCNO> 69647 </DOCNO>
The Impact of |Delta I|=5/2 Transitions in K-> pi pi Decays


  We consider the impact of isospin violation on the analysis of K-> pi pi
decays. We scrutinize, in particular, the phenomenological role played by the
additional weak amplitude, of |Delta I|=5/2 in character, incurred by the
presence of isospin violation. We show that Watson's theorem is appropriate in
O(m_d-m_u), so that the inferred pi-pi phase shift at sqrt{s}=m_K determines
the strong phase difference between the I=0 and I=2 amplitudes in K-> pi pi
decay. We find the magnitude of the |Delta I|=5/2 amplitude thus implied by the
empirical branching ratios to be larger than expected from estimates of
isospin-violating strong and electromagnetic effects. We effect a new
determination of the octet and 27-plet coupling constants with
strong-interaction isospin violation and with electromagnetic effects, as
computed by Cirigliano, Donoghue, and Golowich, and find that we are unable to
resolve the difficulty. Exploring the role of |Delta I|=5/2 transitions in the
CP-violating observable epsilon'/epsilon, we determine that the presence of a
|Delta I|=5/2 amplitude impacts the empirical determination of omega, the ratio
of the real parts of the |Delta I|=3/2 to |Delta I|=1/2 amplitudes, and that it
generates a decrease in the estimation of epsilon'/epsilon.

</DOC>
<DOC>
<DOCNO> 11390 </DOCNO>
Soap Froths and Crystal Structures


  We propose a physical mechanism to explain the crystal symmetries found in
macromolecular and supramolecular micellar materials. We argue that the packing
entropy of the hard micellar cores is frustrated by the entropic interaction of
their brush-like coronas. The latter interaction is treated as a surface effect
between neighboring Voronoi cells. The observed crystal structures correspond
to the Kelvin and Weaire-Phelan minimal foams. We show that these structures
are stable for reasonable areal entropy densities.

</DOC>
<DOC>
<DOCNO> 85344 </DOCNO>
A Comparison of search templates for gravitational waves from binary


  We compare the performances of the templates defined by three different types
of approaches: traditional post-Newtonian templates (Taylor-approximants),
``resummed'' post-Newtonian templates assuming the adiabatic approximation and
stopping before the plunge (P-approximants), and further ``resummed''
post-Newtonian templates going beyond the adiabatic approximation and
incorporating the plunge with its transition from the inspiral
(Effective-one-body approximants). The signal to noise ratio is significantly
enhanced (mainly because of the inclusion of the plunge signal) by using these
new effective-one-body templates relative to the usual post-Newtonian ones for
binary masses greater than $ 30 M_\odot$, the most likely sources for initial
laser interferometers. Independently of the question of the plunge signal, the
comparison of the various templates confirms the usefulness of using
resummation methods. The paper also summarizes the key elements of the
construction of various templates and thus can serve as a resource for those
involved in writing inspiral search software.

</DOC>
<DOC>
<DOCNO> 117019 </DOCNO>
Fast and Flexible CCD Driver System Using Fast DAC and FPGA


  We have developed a completely new type of general-purpose CCD data
acquisition system which enables one to drive any type of CCD using any type of
clocking mode. A CCD driver system widely used before consisted of an analog
multiplexer (MPX), a digital-to-analog converter (DAC), and an operational
amplifier. A DAC is used to determine high and low voltage levels and the MPX
selects each voltage level using a TTL clock. In this kind of driver board, it
is difficult to reduce the noise caused by a short of high and low level in MPX
and also to select many kinds of different voltage levels. Recent developments
in semiconductor IC enable us to use a very fast sampling ($\sim$ 10MHz) DAC
with low cost. We thus develop the new driver system using a fast DAC in order
to determine both the voltage level of the clock and the clocking timing. We
use FPGA (Field Programmable Gate Array) to control the DAC. We have
constructed the data acquisition system and found that the CCD functions well
with our new system. The energy resolution of Mn K$\alpha$ has a full-width at
half-maximum of $\simeq$ 150 eV and the readout noise of our system is $\simeq$
8 e$^-$.

</DOC>
<DOC>
<DOCNO> 116745 </DOCNO>
Theoretical prevision of physical chemical properties of amino acids


  Using the crystal basis model of the genetic code, a set of relations between
the physical-chemical properties of the amino acids are derived and compared
with the experimental data. A prevision for the not yet measured
thermodynamical parameters of three amino acids is done.

</DOC>
<DOC>
<DOCNO> 170329 </DOCNO>
Toward the multiphoton parametric oscillators


  We propose novel types of parametric oscillators generating both three-photon
and four-photon bright light which are accessible for an experiment. The
devices are based on the cascaded down-conversion processes and consist of
second-order media inserted in two-resonant mode cavity. Discussion of
dissipation and quantum features of the system are performed by the
quantum-jump simulation method and concerns to the Wigner functions. The
phase-space multistabilities and critical threshold behavior of three- and
four-photon subharmonics are obtained.

</DOC>
<DOC>
<DOCNO> 13543 </DOCNO>
Nature of traps responsible for failure of MOS devices


  A failure of chips in a huge amount of modern electronic devices is connected
as a rule with the undesirable capturing of charge (electrons and holes) by
traps in a thin insulating film of silicon oxide in transistors. It leads to a
breakdown of transistors or to a destructive change of their characteristics.
It is suggested that silicon oxide will be replaced in the next generation of
nanoscale devices by silicon oxynitride. Therefore, it is very important to
understand the nature of traps in this material. We discuss this nature using
the quantum-chemical simulation.

</DOC>
<DOC>
<DOCNO> 11071 </DOCNO>
On the nature of the negative-conductivity resonance in a superlattice


  Adding a high-frequency ac component to the bias field of a superlattice
induces a synchronous modulation of the velocity with which the electrons
traverse the Brillouin zone. In the presence of inelastic scattering, the
k-space velocity modulation causes a wave-like bunching of the electrons in
k-space, which in turn introduces a high-frequency component in the real-space
current, synchronous with the drive field, but phase-shifted relative to the
latter. For a drive frequency equal to the Bloch frequency, the phase shift is
less than 90 degrees (implying a positive ac conductivity), increasing to 90
degrees in the limit of a vanishing scattering (a purely reactive current). If
the drive frequency is lowered below the Bloch frequency, and the inelastic
scattering rate remains sufficiently low, the phase shift can increase beyond
90 degrees, implying a negative ac conductivity, which peaks at a drive
frequency not far below the Bloch frequency.

</DOC>
<DOC>
<DOCNO> 117753 </DOCNO>
The FIR-Radio Correlation of Wolf-Rayet Galaxies and the Role of Star


  We find that a preliminary classification of LINERs' energetics may be made
in terms of the FIR-radio correlation of Wolf-Rayet galaxies. The AGN- or
starburst-supported LINERs can be distinguished by their FIR-to-radio ratio,
$Q\equiv L(1.4{\rm GHz})/$ $L(60\mu{\rm m})>$ or $<0.01$. It is interesting to
note that almost all the LINERs with inner rings might be starburst- supported,
indicating reduced AGN activities compared with those of the AGN-supported
ones. We also find that a shock-heating phase for the warm dust component might
be important for some starbursts at the burst age of $\ge 10^{7}$ yr, with
$Q<0.001$.

</DOC>
<DOC>
<DOCNO> 69671 </DOCNO>
Measuring the neutrino mass using intense photon and neutrino beams


  We compute the cross section for neutrino-photon scattering taking into
account a neutrino mass. We explore the possibility of using intense neutrino
beams, such as those available at proposed muon colliders, together with high
powered lasers to probe the neutrino mass in photon-neutrino collisions.

</DOC>
<DOC>
<DOCNO> 71121 </DOCNO>
Implications of sigma models in the standard model and beyond


  After a brief introduction to the sigma model in QCD, we discuss how the
sigma model can be relevant in the Standard Model. It is shown to be useful in
the analysis of weak processes, such as the study of $\Delta {I} = 1/2$ rule,
and in the analysis of the Higgs sector as well. The sigma model description is
also shown to be quite useful in searching for the effects of New Physics via
gauge boson self-interactions.

</DOC>
<DOC>
<DOCNO> 119862 </DOCNO>
Theoretical and Experimental Topics on Ultra High Energy Cosmic Rays


  Since their first observation in 1962, the existence of Ultra High Energy
Cosmic Rays (UHECR) remains a mystery in modern astrophysics. Those cosmic
rays, with energies well above 50 EeV ($50\times 10^{18}$eV), can hardly be
accelerated, even in the most active parts of our universe such as FR-II radio
galaxies or AGNs, nor can they travel on distances larger than 100 Mpc. In the
following some of the production and acceleration models for UHECR are reviewed
and some of the transport issues are exposed. Finally the detection and
identification on Earth of those ``cosmic bullets'' are presented.

</DOC>
<DOC>
<DOCNO> 102719 </DOCNO>
Intersecting Legendrians and blowups


  The purpose of this note is to describe the relationship between two classes
of Legendre distributions. These two classes are distributions associated to an
intersecting pair of Legendre submanifolds, introduced by one of us by analogy
with intersecting Lagrangian distributions of Melrose and Uhlmann, and Legendre
distributions associated to a fibred scattering structure introduced by the
authors. We prove a general result, and also give an example in two dimensions,
which shows explicitly the relation between the two spaces in a simple setting.

</DOC>
<DOC>
<DOCNO> 100824 </DOCNO>
Quadratic vanishing cycles, reduction curves and reduction of the


  The geometric monodromy of a plane curve singularity is a quasi-finite
diffeomorphism. In this paper we locate the reduction curves of the geometric
monodromy and the quadratic vanishing cycles of the singularity. An application
to the geometric monodromy group is given.

</DOC>
<DOC>
<DOCNO> 9233 </DOCNO>
Generalizing the Debye-Huckel equation in terms of density functional


  We discuss the validity of generalized Debye-H\"uckel (GDH) equation proposed
by Fisher {\itshape et al.} from the functional integral point of view. The GDH
theory considers fluctuations around prescribed densities of positive and
negative charges. Hence we first formulate a density functional integral
expression for the canonical system of Coulomb gas, and also demonstrate that
this is a dual form to the Sine-Gordon theory. Our formalism reveals the
following: (i) The induced charge distribution around supposed density favors
not only the cancellation of additional electrostatic potential like the
original DH theory, but also the countervailing of chemical potential
difference between imposed and equilibrium value. (ii) As a consequence
apparent charge, absent in the GDH equation, comes out in our generalized
equation. (iii) That is, the GDH equation holds only in special cases.

</DOC>
<DOC>
<DOCNO> 8152 </DOCNO>
Inhomogeneous order-parameter suppression in disordered d-wave


  We report on a numerical study of disorder effects in 2D d-wave BCS
superconductors. We compare exact numerical solutions of the
Bogoliubov-deGennes (BdG) equations for the density of states $\rho(E)$ with
the standard T-matrix approximation. Local suppression of the order parameter
near impurity sites, which occurs in self-consistent solutions of the BdG
equations, leads to apparent power law behavior $\rho(E) \sim |E|^\alpha$ with
non-universal $\alpha$ over an energy scale comparable to the single impurity
resonance energy $\Omega_0$. We show that the novel effects arise from static
spatial correlations between the order parameter and the impurity distribution.

</DOC>
<DOC>
<DOCNO> 68029 </DOCNO>
Computation of the Vortex Free Energy in SU(2) Gauge Theory


  We present the first measurement of the vortex free-energy order parameter at
weak coupling for SU(2) in simulations employing multihistogram methods. The
result shows that the excitation probability for a sufficiently thick vortex in
the vacuum tends to unity. This is rigorously known to provide a necessary and
sufficient condition for maintaining confinement at weak coupling in SU(N)
gauge theories.

</DOC>
<DOC>
<DOCNO> 116668 </DOCNO>
Time series model based on global structure of complete genome


  A time series model based on the global structure of the complete genome is
proposed. Three kinds of length sequences of the complete genome are
considered. The correlation dimensions and Hurst exponents of the length
sequences are calculated. Using these two exponents, some interesting results
related to the problem of classification and evolution relationship of bacteria
are obtained.

</DOC>
<DOC>
<DOCNO> 120069 </DOCNO>
Outflow from YSO and Angular Momentum Transfer


  Dynamical contraction of a slowly-rotating magnetized cloud is studied using
the magnetohydrodynamical (MHD) simulations. In the isothermal stage ($n \la
n_{\rm A} \sim 10^{10}{\rm cm}^{-3}$), the cloud evolves similarly to that
expected from Larson-Penston self-similar solution and experiences the run-away
collapse. However, after the central density exceeds $\sim n_{\rm A}$, an
accretion disk is formed around the adiabatic core. Just outside the core,
outflow is ejected by the effect of magnetic torque (magnetocentrifugal wind).
Since $\sim$ 10% of the mass is ejected with almost all the angular momentum,
the specific angular momentum of the protostellar core reduces to that observed
in main-sequence stars.

</DOC>
<DOC>
<DOCNO> 152059 </DOCNO>
Solitons in Noncommutative Gauge Theory


  We present a unified treatment of classical solutions of noncommutative gauge
theories. We find all solutions of the noncommutative Yang-Mills equations in 2
dimensions; and show that they are labelled by two integers -- the rank of
gauge group and the magnetic charge. The magnetic vortex solutions are unstable
in 2+1 dimensions, but correspond to the full, stable BPS solutions of N=4 U(1)
noncommutative gauge theory in 4 dimensions, that describes N infinite D1
strings that pierce a D3 brane at various points, in the presence of a
background B field in the Seiberg-Witten limit. We discuss the behaviour of
gauge invariant observables in the background of the solitons. We use these
solutions to construct a panoply of BPS and non-BPS solutions of supersymmetric
gauge theories that describe various configurations of D-branes. We analyze the
instabilities of the non-BPS solutions. We also present an exact analytic
solution of noncommutative gauge theory that describes a U(2) monopole.

</DOC>
<DOC>
<DOCNO> 101836 </DOCNO>
The cohomology ring of free loop spaces


  Let X be a simply connected space and k a commutative ring. Goodwillie,
Burghelea and Fiedorowiscz proved that the Hochschild cohomology of the
singular chains on the pointed loop space HH^{*}S_*(\Omega X) is isomorphic to
the free loop space cohomology H^{*}(X^{S^{1}}). We proved that this
isomorphism is compatible with both the cup product on HH^{*}S_*(\Omega X) and
on H^{*}(X^{S^{1}}). In particular, we explicit the algebra H^{*}(X^{S^{1}})
when X is a suspended space, a complex projective space or a finite CW-complex
of dimension p such that \frac {1}{(p-1)!}\in k.

</DOC>
<DOC>
<DOCNO> 151499 </DOCNO>
Brane Potentials and Moduli Spaces


  It is shown that the supergravity moduli spaces of D1-D5 and D2-D6 brane
systems coincide with those of the Coulomb branches of the associated
non-abelian gauge theories. We further discuss situations in which worldvolume
brane actions include a potential term generated by probing certain
supergravity backgrounds. We find that in many cases, the appearance of the
potential is due to the application of the Scherk-Schwarz mechanism. We give
some examples and discuss the existence of novel supersymmetric brane
configurations.

</DOC>
<DOC>
<DOCNO> 68495 </DOCNO>
Nuclear Shadowing and Coherence Length for Longitudinal and Transverse


  Motivated by the recent results for DIS off nuclei from the HERMES experiment
we have performed a systematic study of shadowing for transverse and
longitudinal photons. We found that the coherence length which controls the
onset of nuclear shadowing at small x_{Bj} is much longer for longitudinal than
transverse photons, and is much shorter for shadowing of gluons. The light-cone
Green function approach we apply properly treats shadowing in the transition
region x_{Bj}>0.01. It also incorporates the nonperturbative effects and is
legitimate at small Q^2. We calculate nuclear shadowing and compare with data
from the HERMES and NMC experiments. Although we expect different nuclear
shadowing for longitudinal and transverse photons, numerically it cannot
explain the strong effect observed by the HERMES collaboration.

</DOC>
<DOC>
<DOCNO> 84537 </DOCNO>
Negative mode problem in false vacuum decay with gravity


  There is a single negative mode in the spectrum of small perturbations about
the tunneling solutions describing a metastable vacuum decay in flat spacetime.
This mode is needed for consistent description of decay processes. When gravity
is included the situation is more complicated. An approach based on elimination
of scalar field perturbations shows no negative mode, whereas the recent
approach based on elimination of gravitational perturbations indicates presence
of a negative mode. In this contribution we analyse and compare the present
approaches to the negative mode problem in false vacuum decay with gravity.

</DOC>
<DOC>
<DOCNO> 120708 </DOCNO>
The First Six Days of The Universe


  The early stage of the Universe is discussed and the time lengths of its
first six days, as well as its age, are given. There seems to be no
contradiction with the Bible's ascertain that the Universe was created in six
days.

</DOC>
<DOC>
<DOCNO> 83241 </DOCNO>
Prosody-Based Automatic Segmentation of Speech into Sentences and Topics


  A crucial step in processing speech audio data for information extraction,
topic detection, or browsing/playback is to segment the input into sentence and
topic units. Speech segmentation is challenging, since the cues typically
present for segmenting text (headers, paragraphs, punctuation) are absent in
spoken language. We investigate the use of prosody (information gleaned from
the timing and melody of speech) for these tasks. Using decision tree and
hidden Markov modeling techniques, we combine prosodic cues with word-based
approaches, and evaluate performance on two speech corpora, Broadcast News and
Switchboard. Results show that the prosodic model alone performs on par with,
or better than, word-based statistical language models -- for both true and
automatically recognized words in news speech. The prosodic model achieves
comparable performance with significantly less training data, and requires no
hand-labeling of prosodic events. Across tasks and corpora, we obtain a
significant improvement over word-only models using a probabilistic combination
of prosodic and lexical information. Inspection reveals that the prosodic
models capture language-independent boundary indicators described in the
literature. Finally, cue usage is task and corpus dependent. For example, pause
and pitch features are highly informative for segmenting news speech, whereas
pause, duration and word-based cues dominate for natural conversation.

</DOC>
<DOC>
<DOCNO> 80645 </DOCNO>
Topologically Unquenched QCD: Prospects from an explorative study in


  The concept of simulating a variant of QCD with sea quarks which interact
with the gluon configuration only via global gluonic quantities like $\int
F\tilde F dx$ and $\int FF dx$ is tested for the case of the massive 2-flavour
Schwinger model. It is found to amount to an importance sampling method which
generates -at essentially the costs of a quenched run- an ensemble in between a
full and a quenched one, thus providing a competitive alternative to the
quenched approximation.

</DOC>
<DOC>
<DOCNO> 152517 </DOCNO>
Tachyon condensation and universality of DBI action


  We show that a low-energy action for massless fluctuations around a tachyonic
soliton background representing a codimension one D-brane coincides with the
Dirac-Born-Infeld action. The scalar modes which describe transverse
oscillations of the D-brane are translational collective coordinates of the
soliton. The appearance of the DBI action is a universal feature independent of
details of a tachyon effective action, provided it has the structure implied by
the open string sigma model partition function.

</DOC>
<DOC>
<DOCNO> 39903 </DOCNO>
A Neutrino-Factory Muon Storage Ring to Provide Beams for Multiple


  We briefly discuss the physics motivation for a neutrino factory with varying
baseline distances of about 1000 to 9000 km. We describe the amount of non
planarity of the storage ring required to service three or four detectors at
once. A novel bowtie storage ring is described that could in part provide these
beams; a preliminary lattice design is given. We give the space angles between
the various detector locations and possible sites for neutrino factories.
Finally we describe detectors at the Gran Sasso Laboratory and at a new
laboratory near Carlsbad, NM to observe the neutrino interactions with wrong
sign leptons.

</DOC>
<DOC>
<DOCNO> 121503 </DOCNO>
The Proper Motion, Parallax, and Origin of the Isolated Neutron Star RX


  The isolated neutron star RX J185635-3754 is the closest known neutron star
to the Sun. Based on HST WFPC2 obervations over a 3 year baseline, I report its
proper motion (332 +/- 1 mas/yr at a position angle of 100.3 +/- 0.1 degrees)
and parallax (16.5 +/- 2.3 mas; 61 pc). This proper motion brings the neutron
star from the general vicinity of the Sco-Cen OB association. For an assumed
neutron star radial velocity between -55 and -60 km/s, the runaway O star zeta
Oph, the Upper Sco OB association, and the neutron star come into spatial
coincidence between 0.9 and 1.0 million years ago. RX J185635-3754 may be the
remnant of the original primary of the zeta Oph system. If so, the space
velocity suggests that the neutron star received a kick of about 200 km/s at
birth.

</DOC>
<DOC>
<DOCNO> 102207 </DOCNO>
Recent Developments in the Theory of Lorentz Spaces and Weighted


  The main objective of this work is to bring together two well known and, a
priori, unrelated theories dealing with weighted inequalities for the
Hardy-Littlewood maximal operator $M$, and thus, we consider the boundedness of
$M$ in the weighted Lorentz space $\Lambda^p_u(w)$. Two examples are
historically relevant as a motivation: If $w=1$, this corresponds to the study
of the boundedness $M:L^p(u)\longrightarrow L^p(u),$ which was characterized by
B. Muckenhoupt, giving rise to the so called $A_p$ weights. The second case is
when we take $u=1$. This is a more recent theory, and was completely solved by
M.A. Ari\~no and B. Muckenhoupt in 1991. It turns out that the boundedness
$M:\llo\longrightarrow\llo,$ can be seen to be equivalent to the boundedness of
the Hardy operator $A$ restricted to decreasing functions of $L^p(w)$. The
class of weights satisfying this boundedness is known as $B_p$. Even though the
$A_p$ and $B_p$ classes enjoy some similar features, they come from very
different theories, and so are the techniques used on each case:
Calder\'on--Zygmund decompositions and covering lemmas for $A_p$, rearrangement
invariant properties and positive integral operators for $B_p$. It is our aim
to give a unified version of these two theories. Contrary to what one could
expect, the solution is not given in terms of the limiting cases above
considered (i.e., $u=1$ and $w=1$), but in a rather more complicated condition,
which reflects the difficulty of estimating the distribution function of the
Hardy-Littlewood maximal operator with respect to general measures.

</DOC>
<DOC>
<DOCNO> 68392 </DOCNO>
Phase transitions signal in inelastic hadron collisions


  The consequence of vacuum instability against particles creation is described
using lattice gas model. It is shown that the tail of multiplicity distribution
should decrees slower than any power of $\exp\{-n\}$, but faster than any power
of $1/n$ if the vacuum is unstable against particles creation.

</DOC>
<DOC>
<DOCNO> 13413 </DOCNO>
Generic scale of the "scale-free" growing networks


  We show that the connectivity distributions $P(k,t)$ of scale-free growing
networks ($t$ is the network size) have the generic scale -- the cut-off at
$k_{cut} \sim t^\beta$. The scaling exponent $\beta$ is related to the exponent
$\gamma$ of the connectivity distribution, $\beta=1/(\gamma-1)$. We propose the
simplest model of scale-free growing networks and obtain the exact form of its
connectivity distribution for any size of the network. We demonstrate that the
trace of the initial conditions -- a hump at $k_h \sim k_{cut} \sim t^\beta$ --
may be found for any network size. We also show that there exists a natural
boundary for the observation of the scale-free networks and explain why so few
scale-free networks are observed in Nature.

</DOC>
<DOC>
<DOCNO> 68716 </DOCNO>
Effective theory of NN interactions in a separable representation


  We consider the effective field theory of the NN system in a separable
representation. The pionic part of the effective potential is included
nonperturbatively and approximated by a separable potential. The use of a
separable representation allows for the explicit solution of the
Lippmann-Schwinger equation and a consistent renormalization procedure. The
phase shifts in the $^1S_0$ channel are calculated to subleading order.

</DOC>
<DOC>
<DOCNO> 9412 </DOCNO>
Monte Carlo simulation of GaAs(001) homoepitaxy


  By carrying out Monte Carlo simulations based on the two-species atomic-scale
kinetic growth model of GaAs(001) homoepitaxy and comparing the results with
scanning tunneling microscope images, we show that initial growing islands
undergo the structural transformation before adopting the proper beta2(2x4)
reconstruction.

</DOC>
<DOC>
<DOCNO> 119624 </DOCNO>
Probing High Redshift Radiation Fields with Gamma-Ray Absorption


  The next generation of gamma-ray telescopes may be able to observe gamma-ray
blazars at high redshift, possibly out to the epoch of reionization. The
spectrum of such sources should exhibit an absorption edge due to
pair-production against UV photons along the line of sight. One expects a sharp
drop in the number density of UV photons at the Lyman edge E_{L}. This implies
that the universe becomes transparent after gamma-ray photons redshift below E
(m_{e}c^2)^{2}/E_{L} 18 GeV. Thus, there is only a limited redshift interval
over which GeV photons can pair produce. This implies that any observed
absorption will probe radiation fields in the very early universe, regardless
of the subsequent star formation history of the universe. Furthermore,
measurements of differential absorption between blazars at different redshifts
can cleanly isolate the opacity due to UV emissivity at high redshift. An
observable absorption edge should be present for most reasonable radiation
fields with sufficient energy to reionize the universe. Ly-alpha photons may
provide an important component of the pair-production opacity. Observations of
a number of blazars at different redshifts will thus allow us to probe the rise
in comoving UV emissivity with time.

</DOC>
<DOC>
<DOCNO> 102292 </DOCNO>
Cornucopia of Isospectral Pairs of Metrics on Balls and Spheres with


  This article is the second part of a comprehensive study. In the first part,
the first isospectral pairs of metrics are constructed on balls, spheres, and
other manifolds by a new isospectral construction technique,called
"Anticommutator Technique." In this paper we reformulate this technique in its
most general form and we determine all the isospectral deformations provided by
this method. It turns out that it provides only discrete isospectral
deformations (the continuous deformations are always trivial in this case),
however, we gain a cornucopia of surprising isospectral pairs. Among them the
most striking examples are constructed on spheres such that one of the metrics
is homogeneous (since it is the metric on the geodesic sphere of a 2-point
homogeneous space), while the other is locally inhomogeneous. Finally we
mention an other new feature of this paper: All the previous constructions are
established by means of "spectrally equivalent Endomorphism Spaces". This paper
is the first one where also "spectrally inequivalent Endomorphism Spaces" are
used for constructions.

</DOC>
<DOC>
<DOCNO> 118737 </DOCNO>
Discovery of the optical counterpart and early optical observations of


  We present the discovery observations of the optical counterpart of the
gamma-ray burster GRB990712 taken 4.16 hours after the outburst and discuss its
light curve observed in the V, R and I bands during the first ~35 days after
the outburst. The observed light curves were fitted with a power-law decay for
the optical transient (OT), plus an additional component which was treated in
two different ways. First, the additional component was assumed to be an
underlying galaxy of constant brightness. The resulting slope of the decay is
0.97+/-0.05 and the magnitudes of the underlying galaxy are: V = 22.3 +/- 0.05,
R = 21.75 +/- 0.05 and I = 21.35 +/- 0.05. Second, the additional component was
assumed to be a galaxy plus an underlying supernova with a time-variable
brightness identical to that of GRB980425, appropriately scaled to the redshift
of GRB990712. The resulting slope of the decay is similar, but the
goodness-of-fit is worse which would imply that either this GRB is not
associated with an underlying supernova or the underlying supernova is much
fainter than the supernova associated with GRB980425. The galaxy in this case
is fainter: V = 22.7 +/- 0.05, R = 22.25 +/- 0.05 and I = 22.15 +/- 0.05; and
the OT plus the underlying supernova at a given time is brighter. Measurements
of the brightnesses of the OT and the galaxy by late-time HST observation and
ground-based observations can thus assess the presence of an underlying
supernova.

</DOC>
<DOC>
<DOCNO> 83293 </DOCNO>
Compiling Language Definitions: The ASF+SDF Compiler


  The ASF+SDF Meta-Environment is an interactive language development
environment whose main application areas are definition of domain-specific
languages, generation of program analysis and transformation tools, production
of software renovation tools, and general specification and prototyping. It
uses conditional rewrite rules to define the dynamic semantics and other
tool-oriented aspects of languages, so the effectiveness of the generated tools
is critically dependent on the quality of the rewrite rule implementation.
   The ASF+SDF rewrite rule compiler generates C code, thus taking advantage of
C's portability and the sophisticated optimization capabilities of current C
compilers as well as avoiding potential abstract machine interface bottlenecks.
It can handle large (10 000+ rule) language definitions and uses an efficient
run-time storage scheme capable of handling large (1 000 000+ node) terms. Term
storage uses maximal subterm sharing (hash-consing), which turns out to be more
effective in the case of ASF+SDF than in Lisp or SML. Extensive benchmarking
has shown the time and space performance of the generated code to be as good as
or better than that of the best current rewrite rule and functional language
compilers.

</DOC>
<DOC>
<DOCNO> 69555 </DOCNO>
The Oscillation Probability of GeV Solar Neutrinos of All Active Species


  In this paper, I address the oscillation probability of O(GeV) neutrinos of
all active flavours produced inside the Sun and detected at the Earth. Flavours
other than electron-type neutrinos may be produced, for example, by the
annihilation of WIMPs which may be trapped inside the Sun. In the GeV energy
regime, matter effects are important both for the ``1-3'' system and the
``1-2'' system, and for different neutrino mass hierarchies. A numerical scan
of the multidimensional three-flavour parameter space is performed,
``inspired'' by the current experimental situation. One important result is
that, in the three-flavour oscillation case, P{alpha,beta} is different from
P{beta,alpha} for a significant portion of the parameter space, even if there
is no CP-violating phase in the MNS matrix. Furthermore, P{mu,mu} has a
significantly different behaviour from P{tau,tau}, which may affect
expectations for the number of events detected at large neutrino telescopes.

</DOC>
<DOC>
<DOCNO> 119544 </DOCNO>
Possible Detection of Gamma Ray Air Showers in Coincidence with BATSE


  Project GRAND presents the results of a search for coincident high-energy
gamma ray events in the direction and at the time of nine Gamma Ray Bursts
(GRBs) detected by BATSE. A gamma ray has a non-negligible hadron production
cross section; for each gamma ray of energy of 100 GeV, there are 0.015 muons
which reach detection level (Fasso & Poirier, 1999). These muons are identified
and their angles are measured in stations of eight planes of proportional wire
chambers (PWCs). A 50 mm steel plate above the bottom pair of planes is used to
distinguish muons from electrons. The mean angular resolution is 0.26 degrees
over a +/- 61 degree range in the XZ and YZ planes. The BATSE GRB catalogue is
examined for bursts which are near zenith for Project GRAND. The geometrical
acceptance is calculated for each of these events. The product is then taken of
the GRB flux and GRAND's geometrical acceptance. The nine sources with the best
combination of detection efficiency and BATSE's intensity are selected to be
examined in the data. The most significant detection of these nine sources is
at a statistical significance of +3.7 sigma; this is also the GRB with the
highest product of GRB flux and geometrical acceptance.

</DOC>
<DOC>
<DOCNO> 12102 </DOCNO>
Josephson scanning tunneling microscopy


  We propose a set of scanning tunneling microscopy experiments in which the
surface of superconductor is scanned by a superconducting tip. Potential
capabilities of such experimental setup are discussed. Most important
anticipated results of such an experiment include the position-resolved
measurement of the superconducting order parameter and the possibility to
determine the nature of the secondary component of the order parameter at the
surface. The theoretical description based on the tunneling Hamiltonian
formalism is presented.

</DOC>
<DOC>
<DOCNO> 178980 </DOCNO>
The nucleon and mesons effective masses in the Relativistic Mean-Field


  Nucleon and meson effective masses in the nonlinear Relativistic Mean - Field
Theory (RMF) introducing a nonlinear omega - rho and sigma coupling motivated
by the Quark Meson Coupling model (QMC) is explored. It is shown that, in
contrast to the usual Walecka model, not only the effective nucleon mass
m_{eff,N} but also the effective sigma, rho meson masses (m_{eff, sigma},
m_{eff, rho}) and the effective omega meson mass m_{eff, omega} are nucleon
density dependent.

</DOC>
<DOC>
<DOCNO> 119075 </DOCNO>
Great Circle tidal streams: evidence for a nearly spherical massive dark


  An all high-latitude sky survey for cool carbon giant stars in the Galactic
halo has revealed 75 such stars, of which the majority are new detections. Of
these, more than half are clustered on a Great Circle on the sky which
intersects the center of Sagittarius dwarf galaxy (Sgr) and is parallel to its
proper motion vector, while many of the remainder are outlying Magellanic Cloud
C-stars. A pole-count analysis of the carbon star distribution clearly
indicates that the Great Circle stream we have isolated is statistically
significant, being a 5-6 sigma over-density. These two arguments strongly
support our conclusion that a large fraction of the Halo carbon stars
originated in Sgr. The stream orbits the Galaxy between the present location of
Sgr, 16 kpc from the Galactic center, and the most distant stream carbon star,
at ~60 kpc. It follows neither a polar nor a Galactic plane orbit, so that a
large range in both Galactic R and z distances are probed. That the stream is
observed as a Great Circle indicates that the Galaxy does not exert a
significant torque upon the stream, so the Galactic potential must be nearly
spherical in the regions probed by the stream. We present N-body experiments
simulating this disruption process as a function of the distribution of mass in
the Galactic halo. A likelihood analysis shows that, in the Galactocentric
distance range 16 kpc < R < 60 kpc, the dark halo is most likely almost
spherical. We rule out, at high confidence levels, the possibility that the
Halo is significantly oblate, with isodensity contours of aspect q_m < 0.7.
This result is quite unexpected and contests currently popular galaxy formation
models. (Abridged)

</DOC>
<DOC>
<DOCNO> 100884 </DOCNO>
Mirror symmetry for open strings


  We discuss the generation of superpotentials in four-dimensional, N = 1
supersymmetric field theories arising from type IIA D6-branes wrapped on
supersymmetric three-cycles of a Calabi-Yau threefold. In general, nontrivial
superpotentials arise from sums over disc instantons. We find several examples
of special Lagrangian three-cycles with nontrivial topology which are mirror to
obstructed rational curves, conclusively demonstrating the existence of such
instanton effects. In addition, we present explicit examples of disc instantons
ending on the relevant three-cycles. Finally, we give a preliminary
construction of a mirror map for the open string moduli, in a large-radius
limit of the type IIA compactification.

</DOC>
<DOC>
<DOCNO> 9198 </DOCNO>
Elastic property of single double-stranded DNA molecules: Theoretical


  This paper aims at a comprehensive understanding on the novel elastic
property of double-stranded DNA (dsDNA) discovered very recently through
single-molecule manipulation techniques. A general elastic model for
double-stranded biopolymers is proposed and a new structural parameter called
the folding angle $\phi$ is introduced to characterize their deformations. The
mechanical property of long dsDNA molecules is then studied based on this
model, where the base-stacking interactions between DNA adjacent nucleotide
basepairs, the steric effects of basepairs, and the electrostatic interactions
along DNA backbones are taken into account. Quantitative results are obtained
by using path integral method, and excellent agreement between theory and the
observations reported by five major experimental groups are attained. The
strong intensity of the base-stacking interactions ensures the structural
stability of DNA, while the short-ranged nature of such interactions makes
externally-stimulated large structural fluctuations possible. The entropic
elasticity, highly extensibility, and supercoiling property of DNA are all
closely related to this account. The present work also suggests the possibility
that negative torque can induce structural transitions in highly extended DNA
from right-handed B-form to left-handed configurations similar with Z-form
configuration. Some formulae concerned with the application of path integral
method to polymeric systems are listed in the Appendix.

</DOC>
<DOC>
<DOCNO> 117297 </DOCNO>
Perturbative treatment of intercenter coupling in Redfield theory


  The quantum dynamics of coupled subsystems connected to a thermal bath is
studied. In some of the earlier work the effect of intercenter coupling on the
dissipative part was neglected. This is equivalent to a zeroth-order
perturbative expansion of the damping term with respect to the intercenter
coupling. It is shown numerically for two coupled harmonic oscillators that
this treatment can lead to artifacts and a completely wrong description, for
example, of a charge transfer processes even for very weak intercenter
coupling. Here we perform a first-order treatment and show that these artifacts
disappear. In addition, we demonstrate that the thermodynamic equilibrium
population is almost reached even for strong intercenter coupling strength.

</DOC>
<DOC>
<DOCNO> 119891 </DOCNO>
Air shower simulation using {\sc geant4} and commodity parallel


  We present an evaluation of a simulated cosmic ray shower, based on {\sc
geant4} and {\sc top-c}, which tracks all the particles in the shower. {\sc
top-c} (Task Oriented Parallel C) provides a framework for parallel algorithm
development which makes tractable the problem of following each particle. This
method is compared with a simulation program which employs the Hillas thinning
algorithm.

</DOC>
<DOC>
<DOCNO> 170416 </DOCNO>
Quantum propagators in a random metric


  We consider second order differential operators with coefficients which are
Gaussian random fields. When the covariance becomes singular at short distances
then the propagators of the Schr\"odinger equation as well as of the wave
equation behave in an anomalous way. In particular, the Feynman propagator for
the wave equation is less singular than the one with deterministic
coefficients. We suggest some applications to quantum gravity.

</DOC>
<DOC>
<DOCNO> 117149 </DOCNO>
A variational Monte Carlo calculation of dynamic multipole


  The first three dynamic multipole polarizabilities for the ground state of
hydrogen, helium, hydride ion, and positronium hydride PsH have been computed
using the variational Monte Carlo (VMC) method and explicitly correlated wave
functions. Results for the static dipole polarizability by means of the
diffusion Monte Carlo (DMC) method and the finite field approach show the VMC
results to be quite accurate. From these dynamic polarizabilities van der Waals
dispersion coefficients for the interaction of PsH with ordinary electronic
systems can be computed, allowing one to predict the dispersion energy for the
interaction between PsH and less exotic atoms and molecules.

</DOC>
<DOC>
<DOCNO> 150393 </DOCNO>
Finite Action in d5 Gauged Supergravity and Dilatonic Conformal Anomaly


  Gauged supergravity (SG) with single scalar (dilaton) and arbitrary scalar
potential is considered. Such dilatonic gravity describes special RG flows in
extended SG where scalars lie in one-dimensional submanifold of total space.
The surface counterterm and finite action for such gauged SG in three-, four-
and five-dimensional asymptotically AdS space are derived. Using finite action
and consistent gravitational stress tensor (local surface counterterm
prescription) the regularized expressions for free energy, entropy and mass of
d4 dilatonic AdS black hole are found. The same calculation is done within
standard reference background subtraction.
  The dilaton-dependent conformal anomaly from d3 and d5 gauged SGs is
calculated using AdS/CFT correspondence. Such anomaly should correspond to two-
and four-dimensional dual quantum field theory which is classically (not
exactly) conformally invariant, respectively. The candidate c-functions from d3
and d5 SGs are suggested. These c-functions which have fixed points in
asymptoticaly AdS region are expressed in terms of dilatonic potential and they
are positively defined and monotonic for number of potentials.

</DOC>
<DOC>
<DOCNO> 122669 </DOCNO>
XMM-Newton monitoring of X-ray variability in the quasar PKS 0558-504


  We present the temporal analysis of X-ray observations of the radio-loud
Narrow-Line Seyfert 1 galaxy (NLS1) PKS 0558-504 obtained during the XMM-Newton
Calibration and Performance Verification (Cal/PV) phase. The long term light
curve is characterized by persistent variability with a clear tendency for the
X-ray continuum to harden when the count rate increases. Another strong
correlation on long time scales has been found between the variability in the
hard band and the total flux. On shorter time scales the most relevant result
is the presence of smooth modulations, with characteristic time of ~ 2 hours
observed in each individual observation. The short term spectral variability
turns out to be rather complex but can be described by a well defined pattern
in the hardness ratio-count rate plane.

</DOC>
<DOC>
<DOCNO> 119927 </DOCNO>
A Search for Stars of Very Low Metal Abundance. V. Photoelectric UBV


  We report photoelectric UBV data for 268 metal-poor candidates chosen from
the northern HK objective-prism/interference-filter survey of Beers and
colleagues. Over 40 % of the stars have been observed on more than one night,
and most have at least several sets of photometric measurements. Reddening
estimates, preliminary spectroscopic measurements of abundance, and type
classifications are reported.

</DOC>
<DOC>
<DOCNO> 119904 </DOCNO>
Compact Groups of Galaxies in the Las Campanas Redshift Survey


  We have recently extracted a catalog of compact groups of galaxies (CGs) from
the Las Campanas Redshift Survey. This catalog of Las Campanas Compact Groups
(LCCGs) contains 76 CGs with a median redshift of z_med = 0.08. The physical
properties of these CGs are similar to those from the Hickson (1982) and the
Barton et al. (1996) catalogs. Here, we present an atlas of our catalog and
briefly describe its general properties.

</DOC>
<DOC>
<DOCNO> 11248 </DOCNO>
Semiclassical theory of shot noise in disordered SN contacts


  We present a semiclassical theory of shot noise in diffusive superconductor -
normal metal contacts. At subgap voltages, we reproduce the doubling of shot
noise with respect to conventional normal-metal contacts, which is interpreted
in terms of an energy balance of electrons. Above the gap, the voltage
dependence of the noise crosses over to the standard one with a
voltage-independent excess noise. The semiclassical description of noise leads
to correlations between currents at different electrodes of multiterminal SN
contacts which are always of fermionic type, i.e. negative. Using a quantum
extension of the Boltzmann - Langevin method, we reproduce the peculiarity of
noise at the Josephson frequency and obtain an analytical frequency dependence
of noise at above-gap voltages.

</DOC>
<DOC>
<DOCNO> 13754 </DOCNO>
Hysteretic behavior of a polymer molecule immersed in an incompatible


  The radius of gyration of a polymer chain immersed in a low molecular weight
solvent is known to vary monotonically with the solvent quality. Here, we
consider the behavior of a chain immersed in a high molecular weight solvent
(polymer melt). Unsurprisingly, we find that, as the incompatibility between
the chain and the polymer melt is increased, the two limiting conformations of
the chain are the ideal random coil (R = aN^1/2) and the dense globule (R =
aN^1/3). We show, however, that between these two limits the radius of gyration
of the chain presents a hysteretic behavior .

</DOC>
<DOC>
<DOCNO> 70098 </DOCNO>
Three loop MSbar tensor current anomalous dimension in QCD


  The anomalous dimensions of the general flavour non-singlet quark bilinear
currents \psi \gamma^{[\mu_1} ... \gamma^{\mu_n]} \psi are computed at three
loops in quantum chromodynamics in the minimal subtraction scheme. The
dimension of the tensor current emerges for the case n = 2 and the anomalous
dimension for the general flavour singlet current is also discussed.

</DOC>
<DOC>
<DOCNO> 119270 </DOCNO>
Anomalous Radio-Wave Scattering from Interstellar Plasma Structures


  This paper considers scattering screens that have arbitrary spatial
variations of scattering strength transverse to the line of sight, including
screens that are spatially well confined, such as disks and filaments. We
calculate the scattered image of a point source and the observed pulse shape of
a scattered impulse. The consequences of screen confinement include: (1) Source
image shapes that are determined by the physical extent of the screen rather
than by the shapes of much-smaller diffracting microirregularities. These
include image elongations and orientations that are frequency dependent. (2)
Variation with frequency of angular broadening that is much weaker than the
trademark \nu^{-2} scaling law (for a cold, unmagnetized plasma), including
frequency-independent cases; and (3) Similar departure of the pulse broadening
time from the usually expected \nu^{-4} scaling law. We briefly discuss
applications that include scattering of pulses from the Crab pulsar by
filaments in the Crab Nebula; image asymmetries from Galactic scattering of the
sources Cyg X-3, Sgr A*, and NGC 6334B; and scattering of background active
galactic nuclei by intervening galaxies. We also address the consequences for
inferences about the shape of the wavenumber spectrum of electron density
irregularities, which depend on scaling laws for the image size and the pulse
broadening. Future low-frequency (< 100 MHz) array observations will also be
strongly affected by the Galactic structure of scattering material. Our
formalism is derived in the context of radio scattering by plasma density
fluctuations. It is also applicable to optical, UV and X-ray scattering by
grains in the interstellar medium.

</DOC>
<DOC>
<DOCNO> 119451 </DOCNO>
Possible manifestations of the graviton background


  Possible effects are considered which would be caused by a hypothetical
superstrong interaction of photons or massive bodies with single gravitons of
the graviton background. If full cosmological redshift magnitudes are caused by
the interaction, then the luminosity distance in a flat non-expanding universe
as a function of redshift is very similar to the specific function which fits
supernova cosmology data by Riess et al. From another side, in this case every
massive body, slowly moving relatively to the background, would experience a
constant acceleration, proportional to the Hubble constant, of the same order
as a small additional acceleration of Pioneer 10, 11.

</DOC>
<DOC>
<DOCNO> 72102 </DOCNO>
A supersymmetric 3-3-1 model


  We build the complete supersymmetric version of a 3-3-1 gauge model using the
superfield formalism. We point out that a discrete symmetry, similar to the
R-symmetry in the minimal supersymmetric standard model, is possible to be
defined in this model. Hence we have both R-conserving and R-violating
possibilities. Analysis of the mass spectrum of the neutral real scalar fields
shown that in this model the lightest scalar Higgs has a mass upper limit, and
at the tree level it is 124.5 GeV for a given illustrative set of parameters.

</DOC>
<DOC>
<DOCNO> 100932 </DOCNO>
Adiabatic limits of closed orbits for some Newtonian systems in R^n


  We deal with a Newtonian system like x'' + V'(x) = 0. We suppose that V: \R^n
\to \R possesses an (n-1)-dimensional compact manifold M of critical points,
and we prove the existence of arbitrarity slow periodic orbits. When the period
tends to infinity these orbits, rescaled in time, converge to some closed
geodesics on M.

</DOC>
<DOC>
<DOCNO> 122393 </DOCNO>
Determining the Geometry and the Cosmological Parameters of the Universe


  We study Sunyaev-Zeldovich Effect (SZE) cluster counts in different
cosmologies. It is found that even without the full knowledge of the redshift
distribution of SZE clusters, one can still readily distinguish a flat universe
with a cosmological constant from an open universe. We divide clusters into a
low redshift group (with redshift z<0.5) and a high redshift group (with z>1),
and compute the relation r=N(z<0.5)/N(z>1), where N is the number of
flux-limited (S_lim) SZE clusters. With about the same total number of SZE
clusters N(z>0), the r-value for a flat universe with a consmological constant
and that for an open universe occupy different regions in the S_lim -- r plot
for the most likely cosmological parameters 0.25<\Omega_0<0.35 and
0.2<\Gamma<0.3, where \Gamma is the shape parameter of the initial power
spectrum of density fluctuations. Thus, with a deep SZE cluster survey, the
ratio r can reveal, independent of the normalization of the power spectrum,
whether we are living in a low-density flat universe or an open universe.
  Within the flat universe scenario, the SZE cluster-normalized \sigma_8 has
also been investigated in this work, where sigma_8 is the r.m.s. density
fluctuations within the top-hat scale of 8 h^{-1} Mpc. A functional relation
sigma_8 \sim \Omega_0^{-0.13} is found. Combining it with the X-ray
cluster-normalized \sigma_8\sim\Omega_0^{-0.52+0.13\Omega_0}, one can put tight
constraints on both \Omega_0 and \sigma_8 simulataneously.

</DOC>
<DOC>
<DOCNO> 11858 </DOCNO>
New interpretation of slave boson mean-field theory of the $t-J$ model:


  The $t-J$ Hamiltonian is studied in a mean-field approximation by taking into
account antiferromagnetic and d-wave pairing correlations. Considering the
presence of antiferromagnetic fluctuations, the weaknesses of a mean-field
approximation and the limitation of the $t-J$ model near half-filling, we give
a new interpretation to the slave boson mean-field theory of the $t-J$ model.
We argue that due to phase coherence-breaking antiferromagnetic fluctuations
and quantum fluctuations, superconducting long-range order does not appear
strictly in two dimensions. $T_{c}$ resulting from interlayer pairing hopping
can lead to a universal relation, when $T_{c}$ is scaled by $T^{max}_{c}$.
Systematic reduction of superfluid density and increase of
$(\Delta_{d})_{max}/K_{B}T_{c}$ ratio below and near optimal doping have their
natural explanation in our picture. A crossover temperature $T^{0}$ found in
some of magnetic experiments such as NMR is also easily understood in the
present framework.

</DOC>
<DOC>
<DOCNO> 68723 </DOCNO>
Reinterpretation of Effective Chiral Lagrangian


  Effective tree Chiral Lagrangian is interpreted as a power series expansion
of the kinematical variables. In the presence of the strong interaction this
expansion is valid below the unitarity cut, hence in the unphysical region.
 Consequences of this reinterpretation of the Chiral Lagrangian are analysed
for the relation between K-pi and K-pipi transitions.

</DOC>
<DOC>
<DOCNO> 122834 </DOCNO>
Current Status of cosmological models with mixed dark matter


  An analysis of cosmological mixed dark matter models in spatially flat
Friedmann Universe with zero $\Lambda$-term is presented. We argue that the
introduction of cosmic gravity waves helps to satisfy observational
constraints. The analysis of models is based on the confrontation with the mass
function of clusters of galaxies and the CMB anisotropy. The implication of
Press-Schechter formalism allowed to constrain $\sigma_8=0.52 \pm 0.01$. This
normalisation of the spectrum of density perturbations has been used to
calculate numerically the value of the large scale CMB anisotropy and the
relative contribution of cosmological gravitational waves, T/S. We found that
increasing $\Omega_\nu$ weakens the requirements to the value of T/S, however
even for $\Omega_\nu\le 0.4$ the models with $h+n\ge 1.5$ suggest considerable
abundance of gravitational waves, T/S${}^>_\sim 0.3$. Minimisation of the value
T/S is possible only in the range of the red spectra ($n<1$) and small $h$
($<0.6$). However the parameter $\Omega_\nu$ is strongly constrained by $\Delta
T/T$ data on the first acoustic peak of Sakharov oscillations. Assuming that
T/S $\in[0,3]$ and taking into account observational data on the amplitude of
the first acoustic peak we constrain the model parameters. We show that the
considered models admit both moderate red and blue spectra of density
perturbations $n\in [0.9,1.2]$ with rather high abundance hot dark matter,
$\Omega_\nu \in [0.2,0.4]$. Any condition, $n<0.9$ or $\Omega_\nu<0.2$,
decreases the relative amplitude of the first acoustic peak for more than 30%
in comparison with its height measured by BOOMERanG.

</DOC>
<DOC>
<DOCNO> 169709 </DOCNO>
Information-Theoretic Analyses of Two-Level Quantum Systems


  This paper has been superseded by quant-ph/0006009, "Quantum State Estimation
Using Non-separable Measurements".

</DOC>
<DOC>
<DOCNO> 102369 </DOCNO>
Hartogs-Bochner type theorem in projective space


  We prove the following Hartogs-Bochner type theorem: Let $M$ be a
connected $C^2$ hypersurface of $P_n(\mathbb{C})$ ($n\geq 2$) which divides
$P_n(\mathbb{C})$ in two connected open sets $\Omega_1$ and $\Omega_2$. Then
there exists $i \in \{1,2\}$ such that $C^{1}$ CR functions defined on $M$
extends holomorphically to $\Omega_i$.

</DOC>
<DOC>
<DOCNO> 120987 </DOCNO>
Phenomenon of Gamma-Ray Bursts as Relativistic Detonation of Scalar


  In the modern Universe the existence of various forms of scalar fields is
supposed. On the one hand these fields can explain recently discovered positive
$\Lambda$-term(see e.g. Ref. \cite{ref:Sahni}), on the other hand its form
cluster systems creating gravitational wells for galaxies and their clusters.
At that a natural hypothesis is the existence of compact configurations
("stars") from scalar fields with a large enough energy density and total mass.
The hypothesis is that the energy of these fields can be converted in
relativistic plasma by an explosive way. Such process can be initiated by
collision of relativistic particles which form a relativistic microscopic
fireball. Thus effective temperature can amount to value sufficient for change
of phase for scalar fields. Then the wave of relativistic "detonation" similar
to the same process in classical physics will be spread from this source. In
this paper the parameters of such field star and process of detonation are
estimated. If the effect of the indicated change of phase (or something similar
to one) exists, it is possible to get the parameters of relativistic plasma
(macroscopic fireball) which could generate gamma - bursts. If in the modern
Universe there is such unique form of a matter as fields of high density it
would be strange for Nature not to take advantage of the possibility to convert
their energy to radiation by an explosive way.

</DOC>
<DOC>
<DOCNO> 100488 </DOCNO>
Derivations with Quantum Group Action


  The derivations of a left coideal subalgebra B of a Hopf algebra A which are
compatible with the comultiplication of A (that is, the covariant first order
differential calculi, as defined by Woronowicz, on a quantum homogeneous space)
are related to certain right ideals of B. The correspondence is one-to-one if A
is faithfully flat as a right B-module. This generalizes the result for B=A due
to Woronowicz. A definition for the dimension of a first order differential
calculus at a classical point is given. For the quantum 2-sphere S(q,c) of
Podles under the assumptions "q is not a root of unity" and "c is not equal to
-q^(2n)/(q^(2n)+1)^2" for all n=0,1,..., three 2-dimensional covariant first
order differential calculi exist if c=0, one exists if c=-q/(q+1)^2 or
c=q/(-q+1)^2 and none else. This extends a result of Podles.

</DOC>
<DOC>
<DOCNO> 99910 </DOCNO>
Configuration Spaces and the Topology of Curves in Projective Space


  We survey and expand on the work of Segal, Milgram and the author on the
topology of spaces of maps of positive genus curves into $n$-th complex
projective space, $n\geq 1$ (in both the holomorphic and continuous
categories). Both based and unbased maps are studied and in particular we
compute the fundamental groups of the spaces in question. The relevant case
when $n=1$ is given by a non-trivial extension which we fully determine.

</DOC>
<DOC>
<DOCNO> 12267 </DOCNO>
Irreversible and reversible modes of operation of deterministic ratchets


  We discuss a problem of optimization of the energetic efficiency of a simple
rocked ratchet. We concentrate on a low-temperature case in which the
particle's motion in a ratchet potential is deterministic. We show that the
energetic efficiency of a ratchet working adiabatically is bounded from above
by a value depending on the form of ratchet potential. The ratchets with
strongly asymmetric potentials can achieve ideal efficiency of unity without
approaching reversibility. On the other hand we show that for any form of the
ratchet potential a set of time-protocols of the outer force exist under which
the operation is reversible and the ideal value of efficiency is also achieved.
The mode of operation of the ratchet is still quasistatic but not adiabatic.
The high values of efficiency can be preserved even under elevated
temperatures.

</DOC>
<DOC>
<DOCNO> 68565 </DOCNO>
"+-+" Brane Model Phenomenology


  We explore the phenomenology of the recently proposed "+-+" brane model which
has a characteristic anomalously light first Kaluza-Klein mode. We consider the
processes e^+ e^- to mu^+ mu^- and the Kaluza-Klein production e^+ e^- to gamma
KK giving missing visible energy. These in combination with the latest
Cavendish experiments place severe bounds on the parameter space of the model.
We also discuss how forthcoming experiments can test the model for ``natural''
range of the parameters.

</DOC>
<DOC>
<DOCNO> 85504 </DOCNO>
An exact-plane fronted wave solution in metric-affine gravity


  We study plane-fronted electrovacuum waves in metric-affine gravity (MAG)
with cosmological constant in the triplet ansatz sector of the theory. Their
field strengths are, on the gravitational side, curvature
$R_{\alpha}{}^{\beta}$, nonmetricity $Q_{\alpha\beta}$, torsion $T^{\alpha}$
and, on the matter side, the electromagnetic field strength $F$. Here we
basically present, after a short introduction into MAG and its triplet subcase,
the results of earlier joint work with Garcia, Macias, and Socorro. Our
solution is based on an exact solution of Ozsvath, Robinson, and Rozga
describing type N gravitational fields in general relativity as coupled to
electromagnetic null-fields.

</DOC>
<DOC>
<DOCNO> 8452 </DOCNO>
Ab initio treatment of electron correlations in polymers: lithium


  Correlated {\em ab initio} electronic structure calculations are reported for
the polymers lithium hydride chain $[LiH]_{\infty}$ and beryllium hydride
$[Be_{2}H_{4}]_{\infty}$. First, employing a Wannier-function-based approach,
the systems are studied at the Hartree-Fock level, by considering chains
simulating the infinite polymers. Subsequently, for the model system
$[LiH]_{\infty}$, the correlation effects are computed by considering virtual
excitations from the occupied Hartree-Fock Wannier functions of the infinite
chain into the complementary space of localized unoccupied orbitals, employing
a full-configuration-interaction scheme. For $[Be_{2}H_{4}]_{\infty}$, however,
the electron correlation contributions to its ground state energy are
calculated by considering finite clusters of increasing size modelling the
system. Methods such as M$\o$ller-Plesset second-order perturbation theory and
coupled-cluster singles, doubles and triples level of theory were employed.
Equilibrium geometry, cohesive energy and polymerization energy are presented
for both polymers, and the rapid convergence of electron correlation effects,
when based upon a localized orbital scheme, is demonstrated.

</DOC>
<DOC>
<DOCNO> 151077 </DOCNO>
Spherically Symmetric Solutions and Dark Matter on the Brane


  It has recently been suggested that our universe is a three-brane embedded in
a higher dimensional spacetime. In this paper I examine static, spherically
symmetric solutions that satisfy the effective Einstein field equations on a
brane embedded in a five dimensional spacetime. The field equations involve a
term depending on the five dimensional Weyl tensor, so that the solutions will
not be Schwarzschild in general. This Weyl term is traceless so that any
solution of $^{(4)}R=0$ is a possible four dimensional spacetime. Different
solutions correspond to different five dimensional spacetimes and to different
induced energy-momentum tensors on the brane. One interesting possibility is
that the Weyl term could be responsible for the observed dark matter in the
universe.

</DOC>
<DOC>
<DOCNO> 117273 </DOCNO>
Ideal-Chain Collapse in Biopolymers


  A conceptual difficulty in the Hooke's-law description of ideal Gaussian
polymer-chain elasticity is sometimes apparent in analyses of experimental data
or in physical models designed to simulate the behavior of biopolymers. The
problem, the tendency of a chain to collapse in the absence of external forces,
is examined in the following examples: DNA-stretching experiments, gel
electrophoresis, and protein folding. We demonstrate that the application of a
statistical-mechanically derived repulsive force, acting between the chain
ends, whose magnitude is proportional to the absolute temperature and inversely
proportional to the scalar end separation removes this difficulty.

</DOC>
<DOC>
<DOCNO> 122133 </DOCNO>
Mid-infrared imaging and spectroscopy of the enigmatic cocoon stars in


  In an attempt to determine the nature of the enigmatic cocoon stars in the
Quintuplet Cluster, we have obtained mid-infrared imaging and spectrophotometry
of the cluster, using the CAM and SWS instruments on ISO, using SpectroCam-10
on the Palomar 5m telescope, and NICMOS on HST. The spectra show smooth
continua with various dust and ice absorption features. These features are all
consistent with an interstellar origin, and there is no clear evidence for any
circumstellar contribution to these features. We find no spectral line or
feature that could elucidate the nature of these sources. Detailed modeling of
the silicate absorption features shows that they are best reproduced by the mu
Cep profile, which is typical of the interstellar medium, with tau(sil) \sim
2.9. The high spatial resolution mid-IR images show that three of the five
cocoon stars have spatially extended and asymmetric envelopes, with diameters
of \sim 20,000 AUs.
   A reddening law similar to that of Lutz (1999) but with silicate features
based on the mu Cep profile and normalized to our value of tau(sil) is used to
deredden the observed spectrophotometry. The dereddened energy distributions
are characterised by temperatures of 750-925 K, somewhat cooler than determined
from near IR data alone. Models of optically thin and geometrically thick dust
shells, as used by Williams et al. (1987) for very dusty, late-type WC stars,
reproduce the observed SEDs from 4 to 17 mic, and imply shell luminosities of
log(L/L(sun)) \sim 4.5-4.9 for the brightest four components. An analysis of
the various suggestions proposed to explain the nature of the cocoon stars
reveals serious problems with all the hypotheses, and the nature of these
sources remains an enigma.

</DOC>
<DOC>
<DOCNO> 85450 </DOCNO>
Geometry of rotating disk and the Sagnac effect


  In this paper we demonstrate that subsequent application of Lorentz
transformations to the cylindrical coordinates on a rotating disk leaves the
Euclidean metric invariant. Therefore, the geometry on rotating disk is the
Euclidean geometry, and any experiment which do not involve tidal forces or
Coriolis forces cannot identify either the disk rotates or not. We also show
that, from the point of view of external inertial observer, the difference in
the transit times for the light running along a circle of radius R in the
opposite directions (with respect to the rotation) is 2w/c^2 S, where S is the
area the circle, and w is the angle velocity.

</DOC>
<DOC>
<DOCNO> 120219 </DOCNO>
The Contribution of Field OB Stars to the Ionization of the Diffuse


  (Abridged) We present a study of the ionizing stars associated with the
diffuse ionized gas (DIG) and HII regions in the nearby spiral galaxy M33. We
compare our Schmidt H-alpha image to the far-ultraviolet (FUV, 1520A) image
from the Ultraviolet Imaging Telescope (UIT). The H-alpha/FUV ratio is higher
in HII regions than in the DIG, suggesting an older population of ionizing
stars in the DIG. When compared to models of evolving stellar populations, the
N(Lyc)/FUV ratio in HII regions is consistent with a young burst, while the DIG
ratio resembles an older burst population, or a steady state population built
up by constant star formation. The UIT data is complimented with archival FUV
and optical images of a small portion of the disk of M33 obtained with WFPC2 on
HST. Using the HST FUV and optical photometry, we assign spectral types to the
stars observed in DIG and HII regions. The photometry indicates that ionizing
stars are present in the DIG. We compare the predicted ionizing flux with the
amount required to produce the observed H-alpha emission, and find that field
OB stars in the HST images can account for 40% +/- 12% of the ionization of the
DIG, while the stars in HII regions can provide 107% +/- 26% of the H-alpha
luminosity of the HII regions. We do not find any correlation between leakage
of ionizing photons and H-alpha luminosity for the HII regions in these HST
fields. If stellar photons alone are responsible for ionizing the DIG, the
current results are consistent with no or few ionizing photons escaping from
the galaxy.

</DOC>
<DOC>
<DOCNO> 68249 </DOCNO>
Dynamical fermion masses under the influence of Kaluza-Klein fermions in


  The dynamical fermion mass generation in the 4-dimensional brane is discussed
in a model with 5-dimensional Kaluza-Klein fermions in interaction with
4-dimensional fermions. It is found that the dynamical fermion masses are
generated beyond the critical radius of the compactified extra dimensional
space and may be made small compared with masses of the Kaluza-Klein modes.

</DOC>
<DOC>
<DOCNO> 118894 </DOCNO>
EROs in the EIS Fields. I: The AXAF (Chandra) Deep Field


  The publicly available EIS-DEEP optical-NIR data for the AXAF (Chandra) Deep
Field have been used to construct samples of Extremely Red Objects (EROs) using
various single-band and multi-band color criteria. In this work we define as
EROs objects with colors consistent with passively evolving elliptical galaxies
at z $\geq$ 1. The EROs surface densities we derive are intermediate between
previous published values, emphasizing again the need for larger survey areas
to constrain the effects of possible large-scale structure. Although various
single-color selected samples can be derived, the EROs sample selected using
R-Ks > 5, I-Ks > 4, J-Ks > 1.8 jointly is likely to contain the highest
fraction of passively evolving luminous field elliptical galaxies at z >= 1, or
conversely, the lowest fraction of lower redshift interlopers. The surface
density of this multi-band selected EROs sample is consistent with the
conclusion that little or no field elliptical volume density evolution has
occurred in the redshift range 0 > z > 1.5. However, extensive spectroscopic
followup is necessary to confirm this conclusion.

</DOC>
<DOC>
<DOCNO> 101183 </DOCNO>
Gaussian Random Matrix Models for q-deformed Gaussian Random Variables


  We construct a family of random matrix models for the q-deformed Gaussian
random variables G_\mu=a_\mu+a^\star_\mu where the annihilation operators a_\mu
and creation operators a^\star_\nu fulfil the q-deformed commutation relation
a_\mu a^\star_\nu-q a^\star_\nu a_\mu=\Gamma_{\mu\nu}, \Gamma_{\mu\nu} is the
covariance and 0<q<1 is a given number. Important feature of considered random
matrices is that the joint distribution of their entries is Gaussian.

</DOC>
<DOC>
<DOCNO> 40288 </DOCNO>
WW Production Cross Section and W Branching Fractions in e+e- Collisions


  From a data sample of 183 pb^-1 recorded at a center-of-mass energy of roots
= 189 GeV with the OPAL detector at LEP, 3068 W-pair candidate events are
selected. Assuming Standard Model W boson decay branching fractions, the W-pair
production cross section is measured to be sigmaWW = 16.30 +- 0.34(stat.) +-
0.18(syst.) pb. When combined with previous OPAL measurements, the W boson
branching fraction to hadrons is determined to be 68.32 +- 0.61(stat.) +-
0.28(syst.) % assuming lepton universality. These results are consistent with
Standard Model expectations.

</DOC>
<DOC>
<DOCNO> 152535 </DOCNO>
Supersymmetry of RS bulk and brane


  We review the construction of actions with supersymmetry on spaces with a
domain wall. The latter objects act as sources inducing a jump in the gauge
coupling constant. Despite these singularities, supersymmetry can be
formulated, maintaining its role as a square root of translations in this
singular space. The setup is designed for the application in five dimensions
related to the Randall-Sundrum (RS) scenario. The space has two domain walls.
We discuss the solutions of the theory with fixed scalars and full preserved
supersymmetry, in which case one of the branes can be pushed to infinity, and
solutions where half of the supersymmetries are preserved.

</DOC>
<DOC>
<DOCNO> 101305 </DOCNO>
Bifurcating Continued Fractions II


  In an earlier paper we introduced the notion of 'bifurcating continued
fractions' in a heuristic manner. In this paper a formal theory is developed
for the 'bifurcating continued fractions'.

</DOC>
<DOC>
<DOCNO> 69812 </DOCNO>
Limits on Cosmic Matter--Antimatter Domains from Big Bang


  We present detailed numerical calculations of the light element abundances
synthesized in a Universe consisting of matter- and antimatter- domains, as
predicted to arise in some electroweak baryogenesis scenarios. In our
simulations all relevant physical effects, such as baryon-antibaryon
annihilations, production of secondary particles during annihilations, baryon
diffusion, and hydrodynamic processes are coupled to the nuclear reaction
network. We identify two dominant effects, according to the typical spatial
dimensions of the domains. Small antimatter domains are dissipated via neutron
diffusion prior to He4 synthesis at T_He4 \approx 80 keV, leading to a
suppression of the primordial He4 mass fraction. Larger domains are dissipated
below T_He4 via a combination of proton diffusion and hydrodynamic expansion.
In this case the strongest effects on the elemental abundances are due to
anti-p He4 annihilations, leading to an overproduction of He3 relative to H2
and to overproduction of Li6 via non-thermal nuclear reactions. Both effects
may result in light element abundances deviating substantially from the
standard Big Bang Nucleosynthesis yields and from the observationally inferred
values. This allows us to derive stringent constraints on the antimatter
parameters. For some combinations of the parameters, one may obtain both, low
H2 and low He4, at a common value of the cosmic baryon density, a result
seemingly favored by current observational data.

</DOC>
<DOC>
<DOCNO> 116346 </DOCNO>
Heat and Kinetic Theory in 19th-Century Physics Textbooks: The Case of


  Spain was a scientifically backward country in the early 19th-century. The
causes were various political events, the War of Independence, and the reign of
Fernando VII. The introduction of contemporary physics into textbooks was
therefore a slow process. An analysis of the contents of 19th-century Spanish
textbooks is here presented, centred on imponderable fluids, the concept of
energy, the mechanical theory of heat, and the kinetic theory of gases.

</DOC>
<DOC>
<DOCNO> 13348 </DOCNO>
Does strange kinetics imply unusual thermodynamics?


  We introduce a fractional Fokker-Planck equation (FFPE) for Levy flights in
the presence of an external field. The equation is derived within the framework
of the subordination of random processes which leads to Levy flights. It is
shown that the coexistence of anomalous transport and a potential displays a
regular exponential relaxation towards the Boltzmann equilibrium distribution.
The properties of the Levy-flight FFPE derived here are compared with earlier
findings for subdiffusive FFPE. The latter is characterized by a
non-exponential Mittag-Leffler relaxation to the Boltzmann distribution. In
both cases, which describe strange kinetics, the Boltzmann equilibrium is
reached and modifications of the Boltzmann thermodynamics are not required.

</DOC>
<DOC>
<DOCNO> 85168 </DOCNO>
Quantization of massless fields over the static Robertson-Walker space


  Taking the ${\Bbb R}^1 \times H^3$ space as an example, we develop the new
method of quantization of fields over symmetric spaces. We construct the
quantized massless fields of an arbitrary spin over the ${\Bbb R}^1 \times H^3$
space by the resolution over the systems of "plane waves" which are solutions
of the corresponding wave equations. The propagators of these fields are ${\Bbb
R}^1 \times SO(3,1)$-invariant and causal. For spin 0 and 1/2 fields the
propagators are obtained in the explicit form.

</DOC>
<DOC>
<DOCNO> 121867 </DOCNO>
Kinematics, ages, and metallicities of star clusters in NGC 1316: A 3


  We report on multi-object spectroscopy of 37 candidate star clusters around
the giant early-type radio galaxy NGC 1316 (Fornax A), the brightest galaxy in
the Fornax cluster. For the star clusters in this sample, we measure a mean
radial velocity of 1698 +/- 46 km/s, a rotation velocity of 175 +/- 70 km/s,
and a velocity dispersion of 227 +/- 33 km/s within a galactocentric radius of
24 kpc. Using the projected mass estimator and assuming isotropic orbits, the
estimated total mass is (6.6 +/- 1.7) E+11 solar masses within a radius of 24
kpc. The mass is uncertain by about a factor of two, depending on the orbital
assumptions. The implied M/L_B ratio is in the range 3-6. Four star clusters in
our sample are exceptionally luminous (M_V < -12.3). This means that (1) at
least this many clusters in NGC 1316 are up to an order of magnitude more
luminous than the most luminous star cluster in our Galaxy or M31, and (2) that
the S/N ratio of their spectra allows us to measure line strengths with good
accuracy. By comparing the colours and equivalent widths of H-alpha and the Ca
II triplet absorption lines for those bright star clusters in our sample with
those of single-burst population models, we find that they are coeval with an
age of 3.0 +/- 0.5 Gyr. Their metallicities are found to be solar to within
0.15 dex. These results show once again that globular clusters with near-solar
metallicity do form during galactic mergers, and, moreover, that they can
survive disruption processes taking place during the merger (e.g., dynamical
friction, tidal disruption), as well as evaporation. In this respect, NGC 1316
provides a hitherto "missing" evolutionary link between young merger remnants
of age ~0.5 Gyr such as NGC 3597, NGC 3921 and NGC 7252 on one side, and older
giant ellipticals featuring bimodal colour distributions on the other side.

</DOC>
<DOC>
<DOCNO> 13022 </DOCNO>
Gas condensation within a bundle of carbon nanotubes - effects of


  We study the low temperature phase behavior of hydrogen within a bundle of
carbon nanotubes. Because the carbon environment weakens the attraction between
molecules within the same interstitial channel (IC), the ground state of the
one-dimensional (1D) system is an uncondensed gas. When the screened attractive
interaction between molecules in adjacent ICs is taken into account, the
hydrogen ground state is a quasi-1D liquid. The critical temperature of this
system is estimated.

</DOC>
<DOC>
<DOCNO> 11411 </DOCNO>
Molecular mode-coupling theory applied to a liquid of diatomic molecules


  We study the molecular mode coupling theory for a liquid of diatomic
molecules. The equations for the critical tensorial nonergodicity parameters
${\bf F}_{ll'}^m(q)$ and the critical amplitudes of the $\beta$ - relaxation
${\bf H}_{ll'}^m(q)$ are solved up to a cut off $l_{co}$ = 2 without any
further approximations.
 Here $l,m$ are indices of spherical harmonics. Contrary to previous studies,
where additional approximations were applied, we find in agreement with
simulations, that all molecular degrees of freedom vitrify at a single
temperature $T_c$. The theoretical results for the non ergodicity parameters
and the critical amplitudes are compared with those from simulations. The
qualitative agreement is good for all molecular degrees of freedom. To study
the influence of the cut off on the non ergodicity parameter, we also calculate
the non ergodicity parameters for an upper cut off $l_{co}=4$. In addition we
also propose a new method for the calculation of the critical nonergodicity
parameter

</DOC>
<DOC>
<DOCNO> 12472 </DOCNO>
Group selection models in prebiotic evolution


  The evolution of enzyme production is studied analytically using ideas of the
group selection theory for the evolution of altruistic behavior. In particular,
we argue that the mathematical formulation of Wilson's structured deme model
({\it The Evolution of Populations and Communities}, Benjamin/Cumings, Menlo
Park, 1980) is a mean-field approach in which the actual environment that a
particular individual experiences is replaced by an {\it average} environment.
That formalism is further developed so as to avoid the mean-field approximation
and then applied to the problem of enzyme production in the prebiotic context,
where the enzyme producer molecules play the altruists role while the molecules
that benefit from the catalyst without paying its production cost play the
non-altruists role. The effects of synergism (i.e., division of labor) as well
as of mutations are also considered and the results of the equilibrium analysis
are summarized in phase diagrams showing the regions of the space of parameters
where the altruistic, non-altruistic and the coexistence regimes are stable. In
general, those regions are delimitated by discontinuous transition lines which
end at critical points.

</DOC>
<DOC>
<DOCNO> 69042 </DOCNO>
Lattice simulation of the strange quark mass and Fritzsch texture


  We discuss how predictions of Fritzsch textures can be consistent with values
of fermion masses and mixing angles if we embed them in a supersymmetric grand
unified theory.

</DOC>
<DOC>
<DOCNO> 118382 </DOCNO>
The rate of cosmic ray showers at large zenith angles: a step towards


  It is anticipated that the Pierre Auger Observatory can be used to detect
cosmic neutrinos of >10^19 eV that arrive at very large zenith angles. However
showers created by neutrino interactions close to the detector must be picked
out against a background of similar events initiated by cosmic ray nuclei. As a
step towards understanding this background, we have made the first detailed
analysis of air showers recorded at Haverah Park (an array which used similar
detectors to those planned for the Auger Observatory) with zenith angles above
60 degs. We find that the differential shower rate from 60 degs to 80 degs. can
be predicted accurately when we adopt the known primary energy spectrum above
10^17 eV and assume the QGSJET model and proton primaries. Details of the
calculation are given.

</DOC>
<DOC>
<DOCNO> 178610 </DOCNO>
Systematic analysis of \Delta I = 4 bifurcation in A~150 superdeformed


  A simple criterion for the \Delta I = 4 bifurcation is applied to thirty
superdeformed bands in the A~150 mass region. The analysis allows to
differentiate between active and inactive for staggering single-particle
states. The consideration is based on additivity of nonaxial hexadecapole
moment, which plays a key role in the phenomenon.

</DOC>
<DOC>
<DOCNO> 119272 </DOCNO>
RXTE Studies of Long-Term X-ray Spectral Variations in 4U 1820-30


  We present the results of detailed spectral studies of the ultra-compact low
mass X-ray binary (LMXB) 4U 1820-30 carried out with the Rossi X-ray Timing
Explorer (RXTE) during 1996-7. 4U 1820-30 is an ``atoll'' source X-ray burster
(XRB) located in the globular cluster NGC 6624. It is known to have an 11
minute binary period and a ~176 day modulation in its 2--12 keV flux.
Observations were made with the PCA and HEXTE instruments on RXTE at roughly
one-month intervals to sample this long-term period and study flux-related
spectral changes. There are clear correlations between our fitted spectral
parameters and both the broad-band (2--50 keV) flux and the position in the
color-color diagram, as described by the parameter S_a introduced by Mendez et
al. (1999). In addition, we find a strong correlation between the position in
the color-color diagram and the frequencies of the kilohertz quasi-periodic
oscillations (kHz QPOs) reported by Zhang et al. (1998). This lends further
support to the notion that evidence for the last stable orbit in the accretion
disk of 4U 1820-30 has been observed. For a model consisting of Comptonization
of cool photons by hot electrons plus an additional blackbody component, we
report an abrupt change in the spectral parameters at the same accretion rate
at which the kHz QPOs disappear. For a model consisting of a multicolor disk
blackbody plus a cut-off power law, we find that the inner disk radius reaches
a minimum at the same accretion rate at which the kHz QPO frequency saturates,
as expected if the disk reaches the last stable orbit. Both models face
theoretical and observational problems when interpreted physically for this
system.

</DOC>
<DOC>
<DOCNO> 120115 </DOCNO>
The Nature of Solar Polar Rays


  We use time series observations from the SOHO and Yohkoh spacecraft to study
solar polar rays. Contrary to our expectations, we find that the rays are
associated with active regions on the sun and are not features of the polar
coronal holes. They are extended, hot plasma structures formed in the active
regions and projected onto the plane of the sky above the polar coronal holes.
We present new observations and simple projection models that match long-lived
polar ray structures seen in limb synoptic maps. Individual projection patterns
last for at least 5 solar rotations.

</DOC>
<DOC>
<DOCNO> 119102 </DOCNO>
Emission Line AGNs from the REX survey: Results from optical


  We present 71 Emission Line objects selected from the REX survey. Except for
3 of them, for which the presence of an active nucleus is dubious, all these
sources are Active Galactic Nuclei (QSOs, Seyfert galaxies, emission line
radiogalaxies). In addition, we present the spectra of other 19 AGNs included
in a preliminary version of the REX catalog but not in the final one. The
majority (80) of the 90 sources presented in this paper is newly discovered.
Finally, we present the general properties in the radio and in the X-ray band
of all the AGNs discovered so far in the REX survey.

</DOC>
<DOC>
<DOCNO> 118731 </DOCNO>
NGC 6994: an open cluster which is not an open cluster


  We report on CCD photometry in the Johnson B,V and I passbands for 146 stars
in a 9' \times 9' region around the southern aggregate NGC 6994 (C 2056-128),
which appears in the Lynga (1987) catalogue of open star clusters. We argue
that this object is not really an open cluster, but simply a random enhancement
of four bright stars above the background level. This stars sample includes HD
358033 and GSC 05778-0082, together with M 73, which is referred to as a binary
star, but actually represents the whole asterism. Since NGC 6994 is not the
first case (see for instance Carraro and Patat 1995), this raises the
possibility that other open clusters may have been misclassified. We also
suggest that NGC 6994 is unlikely to be an open cluster remnant (OCR).

</DOC>
<DOC>
<DOCNO> 117658 </DOCNO>
HST Observations and Photoionization Modeling of the LINER Galaxy NGC


  We present a study of available Hubble Space Telescope (HST) spectroscopic
and imaging observations of the low ionization nuclear emission line region
(LINER) galaxy NGC 1052. The WFPC2 imagery clearly differentiates extended
nebular Halpha emission from that of the compact core. Faint Object
Spectrograph (FOS) observations provide a full set of optical and UV data
(1200-6800 Angstroms).
  These spectral data sample the innermost region (0."86 x 0."86 ~ 82pc x 82pc)
and exclude the extended Halpha emission seen in the WFPC2 image. The derived
emission line fluxes allow a detailed analysis of the physical conditions
within the nucleus. The measured flux ratio for Halpha/Hbeta,
F{Halpha}/F{Hbeta}=4.53, indicates substantial intrinsic reddening,
E(B-V)=0.42, for the nuclear nebular emission. This is the first finding of a
large extinction of the nuclear emission line fluxes in NGC 1052. If the
central ionizing continuum is assumed to be attenuated by a comparable amount,
then the emission line fluxes can be reproduced well by a simple
photoionization model using a central power law continuum source with a
spectral index of alpha = -1.2 as deduced from the observed flux distribution.
A multi-density, dusty gas gives the best fit to the observed emission line
spectrum. Our calculations show that the small contribution from a highly
ionized gas observed in NGC 1052 can also be reproduced solely by
photoionization modeling. The high gas covering factor determined from our
model is consistent with the assumption that our line of sight to the central
engine is obscured.

</DOC>
<DOC>
<DOCNO> 121992 </DOCNO>
A High Resolution Radio Survey of Class I Protostars


  We report the results of a survey of low mass Class I protostars in the cm
continuum. In the initial survey, seven sources in the Taurus star formation
were observed with the VLA at 0``.25 resolution. All seven sources drive CO
outflows and display Herbig-Haro flows in the optical or near infrared
wavebands. 4/7 sources were detected, two of which are new discoveries in
systems of very low luminosity, one being the lowest luminosity system detected
to date in the cm continuum. Notably, three sources were not detected to a
3-sigma limit of 0.10 mJy/beam, which indicates that significant cm continuum
emission is not a universal feature of Class I systems with outflow activity.
Subsequent observations of HH30, a more evolved Class II system, found no
emission to a 3-sigma limit of 0.03 mJy/beam. After comparison with near
infrared data, we suggest that the discriminating feature of the detected
systems is a relatively high ionisation fraction in the stellar wind. Temporal
variability of the outflow may also play a role. The one relatively bright
source, IRAS 04016+2610 (L1489 IRS), is clearly resolved on a 0``.4 scale at 2
cm and 3.5 cm. Follow-up imaging with MERLIN did not detect this source with a
0``.04 beam, indicating that the radio emission is generated in a region with a
radius of about 25 au, which is broadly similar to the radius of the bipolar
cavities inferred from models of near infrared data. Interpretation of this
system is complicated by the existence of a quadrupolar outflow, which we
originally detected through polarimetric imaging. We present a near infrared H2
image in which a bow shock in the secondary outflow is clearly seen. This
complicated structure may have been caused by a gravitational interaction
between two protostars.

</DOC>
<DOC>
<DOCNO> 68544 </DOCNO>
RG-invariant Sum Rule in a Generalization of Anomaly Mediated SUSY


  We study a generalization of anomaly-mediated supersymmetry breaking (AMSB)
scenarios, under the assumption that the effects of the high-scale theory do
not completely decouple and D-term type contributions can be therefore present.
We investigate the effect of such possible D-term additional contributions to
soft scalar masses by requiring that, for non-vanishing, renormalizable Yukawa
couplings $Y^{ijk} $, the sum of squared soft supersymmetry breaking mass
parameters, $M^2_{ijk} \equiv m_i^2+m_j^2+m_k^2$, is RG-invariant, in the sense
that it becomes independent of the specific ultraviolet boundary conditions as
it occurs in the AMSB models. These type of models can avoid the problem of
tachyonic solutions for the slepton mass spectrum present in AMSB scenarios. We
implement the electroweak symmetry breaking condition and explore the sparticle
spectrum associated with this framework. To show the possible diversity of the
sparticle spectrum, we consider two examples, one in which the D-terms induce a
common soft supersymmetry breaking mass term for all sfermion masses, and
another one in which a light stop can be present in the spectrum.

</DOC>
<DOC>
<DOCNO> 68363 </DOCNO>
What if Dark matter is Bosonic and self-interacting


  Recently the problem of singular galactic cores and over-abundant formation
of dwarf galaxies, inherent to the standard cold dark matter model, had
attracted a great deal of attention. One scenario which may be free of these
problems invokes a self-interacting Bose-field. We find the limiting core
density in this model due to the self-annihilation of the scalar field into its
own relativistic quanta. The limiting density may correspond to the observable
one if there is only one dark matter component. Alternatively, there may be
more than one dark matter species and the annihilation of one species may be
very efficient with subsequent expansion of the other, thus avoiding the
problem of singular cores.

</DOC>
<DOC>
<DOCNO> 68136 </DOCNO>
Dilepton Production and Chiral Symmetry


  We discuss how dilepton production is related to chiral symmetry and its
restoration. We then analyse presently available data by the CERES
collaboration in this context. We find that the present data do not support any
conclusions concerning the restoration of chiral symmetry. We finally provide a
prediction for the dilepton spectrum for the just completed low energy (40 GeV)
run at the SPS.

</DOC>
<DOC>
<DOCNO> 117795 </DOCNO>
Better Astrometric Deblending of Gravitional Microlensing Events by


  Due to the choice of very dense star fields for a higher event rate, the
current microlensing searches suffer from large uncertainties caused by
blending effect. To measure light variations of microlensing events free from
the effect of blending, a newly developed method of Differential Image Analysis
(DIA) was proposed for microlensing searches. However, even with the light
variation curve obtained by using the DIA method, dramatic reduction of the
uncertainty in the determined Einstein time scale is not expected due to the
difficulty in determining the baseline flux of a source star.
  However, we show in this paper that if the blending effect is investigated by
detecting the shift of a source star image centroid, the DIA method will allow
one to detect the blending effect with a significantly enhanced efficiency
compared the efficiency of the current method based on PSF photometry (PSF
method). This is because for a given event the centroid shift measurable by
using the DIA method, $\delta\theta_{\rm c,DIA}$, is {\it always} larger than
the centroid shift measurable by using the PSF method, $\delta\theta_{\rm
c,PSF}$. We find that the ratio $\delta\theta_{\rm c,DIA}/\delta\theta_{\rm
c,DIA}$ rapidly increases with increasing fraction of blended light. In
addition, for events affected by the same fraction of blended light, the ratio
$\delta\theta_{\rm c,DIA}/ \delta \theta_{\rm c,DIA}$ is larger for the event
with a lower amplification. Therefore, centroid shift measurements by using the
DIA method will be an efficient method to detect the blending effect especially
of highly blended events, for which the uncertainties in the determined
Einstein time scale are large, as well as of low amplification events, for
which the current method is highly inefficient.

</DOC>
<DOC>
<DOCNO> 69713 </DOCNO>
Peculiarities in multichannel interaction amplitudes for meson-meson


  Interactions in coupled channels pipi, KKbar and an effective 2pi2pi in
scalar-isoscalar wave have been analysed. Influence of interchannel couplings
on analytical structure of multichannel interaction amplitudes has been
studied. Interplay of S-matrix zeroes and poles and their relation with
parameters of scalar resonances has been investigated.

</DOC>
<DOC>
<DOCNO> 39672 </DOCNO>
Top Polarization at a mu+mu- Collider


  The top quark pairs produced at a polarized muon collider are in a (nearly)
pure spin configuration. This result holds for all center-of-mass energies, and
is insensitive to the next-to-leading order QCD radiative corrections. The
decay products of a polarized top quark show strong angular correlations. We
describe an interesting interference effect between the left-handed and
longitudinally polarized W bosons in top quark decay. This effect is easily
observable in the angular distribution of the charged lepton with respect to
the beam axis.

</DOC>
<DOC>
<DOCNO> 12164 </DOCNO>
Thermoelectric properties of junctions between metal and strongly


  We propose a junction of metal and rare-earth compound semiconductor as the
basis for a possible efficient low-temperature thermoelectric device. If an
overlayer of rare earth atoms differing from the bulk is placed at the
interface, very high values of the figure of merit ZT can be reached at low
temperature. This is due to sharp variation of the transmission coefficient of
carriers across the junction at a narrow energy range, which is intrinsically
linked to the localized character of the overlayer f-orbital.

</DOC>
<DOC>
<DOCNO> 40597 </DOCNO>
Application of Neural Networks for Energy Reconstruction


  The possibility to use Neural Networks for reconstruction of the energy
deposited in the calorimetry system of the CMS detector is investigated. It is
shown that using feed - forward neural network, good linearity, Gaussian energy
distribution and good energy resolution can be achieved. Significant
improvement of the energy resolution and linearity is reached in comparison
with other weighting methods for energy reconstruction.

</DOC>
<DOC>
<DOCNO> 9266 </DOCNO>
Molecular dynamics of a dense fluid of polydisperse hard spheres


  Slow dynamics in a fluid are studied in one of the most basic systems
possible: polydisperse hard spheres. Monodisperse hard spheres cannot be
studied as the slow down in dynamics as the density is increased is preempted
by crystallisation. As the dynamics slow they become more heterogeneous, the
spread in the distances traveled by different particles in the same time
increases. However, the dynamics appears to be less heterogeneous than in
hard-sphere-like colloids at the same volume fraction. The particles which move
least far in a characteristic relaxation time and, particularly, the particles
which move farthest in the same time are clustered, not randomly distributed
throughout the sample. We study the dynamics at three different widths of the
distribution of diameters of the hard spheres. For each width, the relaxation
time is the same function of the compressibility factor, suggesting that this
determines the relaxation time for hard spheres.

</DOC>
<DOC>
<DOCNO> 170127 </DOCNO>
Unconditionally Secure Quantum Bit Commitment Is Possible


  Bit commitment involves the submission of evidence from one party to another
so that the evidence can be used to confirm a later revealed bit value by the
first party, while the second party cannot determine the bit value from the
evidence alone. It is widely believed that secure quantum bit commitment is
impossible due to quantum entanglement cheating, which is codified in a general
impossibility theorem. In this paper, the scope of this general impossibility
proof is extended and analyzed, and gaps are found. Three specific protocols
are described for which the entanglement cheating as given in the impossibility
proof fails to work. One of these protocols, QBC2, is proved to be
unconditionally secure.

</DOC>
<DOC>
<DOCNO> 10063 </DOCNO>
Magnetic Field resulting from non-linear electrical transport in single


  In this letter we report that the current induced destabilization of the
charge ordered (CO) state in a rare-earth manganite gives rise to regions with
ferromagnetic correlation. We did this experiment by measurement of the I-V
curves in single crystal of the CO system
 Pr$_{0.63}$Ca$_{0.37}$MnO$_{3}$ and simultanously measuring the magnetization
of the current carrying conductor using a high T$_c$ SQUID working at T = 77K.
We have found that the current induced destabilization of the CO state leads to
a regime of negative differential resistance which leads to a small enhancement
of the magnetization of the sample, indicating ferromagnetically aligned
moments.

</DOC>
<DOC>
<DOCNO> 11547 </DOCNO>
Maximum entropy, fluctuations and priors


  The method of maximum entropy (ME) is extended to address the following
problem: Once one accepts that the ME distribution is to be preferred over all
others, the question is to what extent are distributions with lower entropy
supposed to be ruled out. Two applications are given. The first is to the
theory of thermodynamic fluctuations. The formulation is exact, covariant under
changes of coordinates, and allows fluctuations of both the extensive and the
conjugate intensive variables. The second application is to the construction of
an objective prior for Bayesian inference. The prior obtained by following the
ME method to its inevitable conclusion turns out to be a special case of what
are currently known under the name of entropic priors.

</DOC>
<DOC>
<DOCNO> 11931 </DOCNO>
Microscopic Theory of Protein Folding Rates.I: Fine Structure of the


  A microscopic theory of the free energy barriers and folding routes for
minimally frustrated proteins is presented, greatly expanding on the
presentation of the variational approach outlined previously [J. J. Portman, S.
Takada, P. G. Wolynes, Phys. Rev. Lett. {\bf 81}, 5237 (1998)]. We choose the
$\lambda$-repressor protein as an illustrative example and focus on how the
polymer chain statistics influence free energy profiles and partially ordered
ensembles of structures. In particular, we investigate the role of chain
stiffness on the free energy profile and folding routes. We evaluate the
applicability of simpler approximations in which the conformations of the
protein molecule along the folding route are restricted to have residues that
are either entirely folded or unfolded in contiguous stretches. We find that
the folding routes obtained from only one contiguous folded region corresponds
to a chain with a much greater persistence length than appropriate for natural
protein chains, while the folding route obtained from two contiguous folded
regions is able to capture the relatively folded regions calculated within the
variational approach. The free energy profiles obtained from the contiguous
sequence approximations have larger barriers than the more microscopic
variational theory which is understood as a consequence of partial ordering.

</DOC>
<DOC>
<DOCNO> 83197 </DOCNO>
Smoothness and decay properties of the limiting Quicksort density


  Using Fourier analysis, we prove that the limiting distribution of the
standardized random number of comparisons used by Quicksort to sort an array of
n numbers has an everywhere positive and infinitely differentiable density f,
and that each derivative f^{(k)} enjoys superpolynomial decay at plus and minus
infinity. In particular, each f^{(k)} is bounded. Our method is sufficiently
computational to prove, for example, that f is bounded by 16.

</DOC>
<DOC>
<DOCNO> 152044 </DOCNO>
Vector Deformations of N=4 Super-Yang-Mills Theory, Pinned Branes, and


  We study a deformation of N=4 Super-Yang-Mills theory by a dimension-5 vector
operator. There is a simple nonlocal "dipole" field-theory that realizes this
deformation. We present evidence that this theory is realized in the setting of
"pinned-branes". The dipoles correspond to open strings that arch out of the
brane. We find the gravitational dual of the theory at large N. We also discuss
the generalization to the (2,0) theory.

</DOC>
<DOC>
<DOCNO> 102360 </DOCNO>
The Morse Index Theorem in semi-Riemannian Geometry


  We prove a semi-Riemannian version of the celebrated Morse Index Theorem for
geodesics in semi-Riemannian manifolds; we consider the general case of both
endpoints variable on two submanifolds. The key role of the theory is played by
the notion of the {\em Maslov index} of a semi-Riemannian geodesic, which is a
homological invariant and it substitutes the notion of geometric index in
Riemannian geometry. Under generic circumstances, the Maslov index of a
geodesic is computed as a sort of {\em algebraic count} of the conjugate points
along the geodesic. For non positive definite metrics the index of the index
form is always infinite; in this paper we prove that the space of all
variations of a given geodesic has a {\em natural} splitting into two infinite
dimensional subspaces, and the Maslov index is given by the difference of the
index and the coindex of the restriction of the index form to these subspaces.
In the case of variable endpoints, two suitable correction terms, defined in
terms of the endmanifolds, are added to the equality. Using appropriate change
of variables, the theory is entirely extended to the more general case of {\em
symplectic differential systems}, that can be obtained as linearizations of the
Hamilton equations.

</DOC>
<DOC>
<DOCNO> 40070 </DOCNO>
Using Multiple RISC CPUs in Parallel to Study Charm Quarks


  We have integrated a system of 16 RISC CPUs to help reconstruct and analyze a
1.3 Terabyte data set of 400 million high energy physics interactions. These
new CPUs provided an affordable means of processing a very large data set. The
data was generated using a hadron beam and a fixed target at Fermilab
Experiment 769. Signals were recorded on tape from particles created in or
decaying near the target and passing though a magnetic spectrometer. Because
all the interactions were independent, each CPU could completely reconstruct
any interaction without reference to other CPUs. Problems of this sort are
ideal for multiple processors. In the offline reconstuction system, we used
Exabyte 8mm video tape drives with an I/O capacity of 7 Terabytes per year and
a storage capacity of 2.3 Gigabytes per tape. This reduced tape mounts to one
or two per day rather than one or two per hour as would be the case with
9-track tapes. The ETHERNET network used to link the CPUs and has an I/O
capacity of 15 Terabytes per year. The RISC CPUs came in the form of
commercially supported workstations with little memory and no graphics to
minimize cost. Each 25 MHz MIPS R3000 RISC CPU processed data 20 times faster
than 16MHz Motorola 68020 CPUs that were also used. About 8000 hours of
processing was needed to reconstruct the data set. A sample of thousands of
fully reconstructed particles containing a charm quark has been produced.

</DOC>
<DOC>
<DOCNO> 71825 </DOCNO>
Solitonic Brane World with Completely Localized (Super)Gravity


  We construct a solitonic 3-brane solution in the 5-dimensional
Einstein-Hilbert-Gauss-Bonnet theory. This solitonic brane is delta-function
like, and has the property that gravity is completely localized on the brane.
That is, there are no propagating degrees of freedom in the bulk, while on the
brane we have purely 4-dimensional Einstein gravity. Thus, albeit the classical
background is 5-dimensional, the quantum theory (perturbatively) is
4-dimensional. Our solution can be embedded in the supergravity context, where
we have completely localized supergravity on the corresponding solitonic brane,
which is a BPS object preserving 1/2 of the original supersymmetries. By
including a scalar field, we also construct a smooth domain wall solution,
which in a certain limit reduces to the delta-function-like solitonic brane
solution (this is possible for the latter breaks diffeomorphisms only
spontaneously). We then show that in the smooth domain wall background the only
normalizable mode is the 4-dimensional graviton zero mode, while all the other
(including massive Kaluza-Klein) modes are not even plane-wave normalizable.
Finally, we observe that in compactifications of Type IIB on 5-dimensional
Einstein manifolds other than a 5-sphere the corresponding dual gauge theories
on D3-branes are not conformal in the ultra-violet, and at the quantum level we
expect the Einstein-Hilbert term to be generated in their world-volumes. We
conjecture that in full string theory on Type IIB side this is due to higher
curvature terms, which cannot be ignored in such backgrounds. A stronger
version of this conjecture also states that (at least in some cases) in such
backgrounds D3-branes are solitonic objects with completely localized
(super)gravity in their world-volumes.

</DOC>
<DOC>
<DOCNO> 12437 </DOCNO>
Ferromagnetism in the Two-Dimensional Periodic Anderson Model


  Using the constrained-path Monte Carlo method, we studied the magnetic
properties of the two-dimensional periodic Anderson model for electron fillings
between 1/4 and 1/2. We also derived two effective low energy theories to
assist in interpreting the numerical results. For 1/4 filling we found that the
system can be a Mott or a charge transfer insulator, depending on the relative
values of the Coulomb interaction and the charge transfer gap between the two
non-interacting bands. The insulator may be a paramagnet or antiferromagnet. We
concentrated on the effect of electron doping on these insulating phases. Upon
doping we obtained a partially saturated ferromagnetic phase for low
concentrations of conduction electrons. If the system were a charge transfer
insulator, we would find that the ferromagnetism is induced by the well-known
RKKY interaction. However, we found a novel correlated hopping mechanism
inducing the ferromagnetism in the region where the non-doped system is a Mott
insulator. Our regions of ferromagnetism spanned a much smaller doping range
than suggested by recent slave boson and dynamical mean field theory
calculations, but they were consistent with that obtained by density matrix
renormalization group calculations of the one-dimensional periodic Anderson
model.

</DOC>
<DOC>
<DOCNO> 13397 </DOCNO>
Peak effect in the vortex state of V$_3$Si: a study of history


  We present results of transport properties measurement on a single crystal of
V$_3$Si showing distinct signature of peak-effect in its vortex state. The
field variation of the electrical resistance in the flux-line lattice prepared
by different experimental path, namely zero field cooling (ZFC) and field
cooling (FC), shows a distinct path dependence in the vicinity of the
peak-effect regime. In the field cooled state, small cycling of magnetic field
modifies the resistance drastically around the peak-effect regime, highlighting
the metastable nature of that state in the concerned regime.

</DOC>
<DOC>
<DOCNO> 174542 </DOCNO>
Time Scales in Spectator Fragmentation


  Proton-proton correlations and correlations of p-alpha, d-alpha, and t-alpha
from spectator decays following Au + Au collisions at 1000 AMeV have been
measured with an highly efficient detector hodoscope. The constructed
correlation functions indicate a moderate expansion and low breakup densities
similar to assumptions made in statistical multifragmentation models. In
agreement with a volume breakup rather short time scales were deduced employing
directional cuts in proton-proton correlations.
  PACS numbers: 25.70.Pq, 21.65.+f, 25.70.Mn

</DOC>
<DOC>
<DOCNO> 71539 </DOCNO>
Bound States from Regge Trajectories in a Scalar Model


  The calculation of bound state properties using renormalization group
techniques to compute the corresponding Regge trajectories is presented. In
particular, we investigate the bound states in different charge sectors of a
scalar theory with interaction (phi^dagger phi chi). The resulting bound state
spectrum is surprisingly rich. Where possible we compare and contrast with
known results of the Bethe-Salpeter equation in the ladder approximation and,
in the non-relativistic limit, with the corresponding Schr"odinger equation.

</DOC>
<DOC>
<DOCNO> 8336 </DOCNO>
Enhancement of Kondo effect in quantum dots with an even number of


  We investigate the Kondo effect in a quantum dot with almost degenerate
spin-singlet and triplet states for an even number of electrons. We show that
the Kondo temperature as a function of the energy difference between the states
Delta reaches its maximum around Delta=0 and decreases with increasing Delta.
The Kondo effect is thus enhanced by competition between singlet and triplet
states. Our results explain recent experimental findings. We evaluate the
linear conductance in the perturbative regime.

</DOC>
<DOC>
<DOCNO> 80969 </DOCNO>
Scale Setting for $\alpha_s$ Beyond Leading Order


  We present a general procedure for applying the scale-setting prescription of
Brodsky, Lepage and Mackenzie to higher orders in the strong coupling constant
$\alphas$. In particular, we show how to apply this prescription when the
leading coefficient or coefficients in a series in $\alphas$ are anomalously
small. We give a general method for computing an optimum scale numerically,
within dimensional regularization, and in cases when the coefficients of a
series are known. We find significant corrections to the scales for $R_{e^+
e^-}$, $\Gamma(B \to X_u e \bar{\nu})$, $\Gamma(t \to b W)$, and the ratios of
the quark pole to $\MSbar$ and lattice bare masses.

</DOC>
<DOC>
<DOCNO> 102477 </DOCNO>
Global regularity of wave maps II. Small energy in two dimensions


  We show that wave maps from Minkowski space $\R^{1+n}$ to a sphere $S^{m-1}$
are globally smooth if the initial data is smooth and has small norm in the
critical Sobolev space $\dot H^{n/2}$, in all dimensions $n \geq 2$. This
generalizes the results in the prequel [math.AP/0010068] of this paper, which
addressed the high-dimensional case $n \geq 5$. In particular, in two
dimensions we have global regularity whenever the energy is small, and global
regularity for large data is thus reduced to demonstrating non-concentration of
energy.

</DOC>
<DOC>
<DOCNO> 70928 </DOCNO>
Phase shift analysis of low energy pi+/- p scattering data and a


  Using newly calculated electromagnetic corrections, we have made a phase
shift analysis of experimental data on pi+/- p elastic scattering up to 100
MeV, assuming the effective hadronic interaction to be isospin invariant. The
output consists of parametrised s and p-wave hadronic phases for isospin 1/2
and 3/2. It is not possible to fit the charge exchange data satisfactorily. We
give values for the s-wave scattering lengths and effective ranges and for the
p-wave scattering volumes. The combinations 2a_1 + a_3 and a_1 - a_3 of s-wave
scattering lengths extracted from pionic hydrogen data are compared with those
obtained from our analysis.

</DOC>
<DOC>
<DOCNO> 100595 </DOCNO>
Semiinfinite cohomology of Lie-* algebras


  We construct a geometric version of BRST cohomology complex of a chiral
module over a Lie-* algebra using the language of differential graded Lie
algebroids in the category of D-modules on a compact curve $X$.

</DOC>
<DOC>
<DOCNO> 8671 </DOCNO>
Statistical characterization of the fixed income market efficiency


  We present cross and time series analysis of price fluctuations in the U.S.
Treasury fixed income market. By means of techniques borrowed from statistical
physics we show that the correlation among bonds depends strongly on the
maturity and bonds' price increments do not fulfill the random walk hyphoteses.

</DOC>
<DOC>
<DOCNO> 123221 </DOCNO>
Radial Oscillations of Rotating Strange Stars in Strong Magnetic Fields


  In this paper we study radial oscillations of rotating strange stars in
strong magnetic fields in the Density Dependent Quark Mass (DDQM) model. We see
that increase of frequency i.e. difference in frequency of rotating and
non-rotating stars is more for higher magnetic fields. The change is small for
low mass stars but it increases with the mass of the star. This change of
frequency is significant for maximum mass whereas it is marginal for a 1.4
solar mass star.

</DOC>
<DOC>
<DOCNO> 116271 </DOCNO>
The Genetic Code as a Periodic Table: Algebraic Aspects


  The systematics of indices of physico-chemical properties of codons and amino
acids across the genetic code are examined. Using a simple numerical labelling
scheme for nucleic acid bases, data can be fitted as low-order polynomials of
the 6 coordinates in the 64-dimensional codon weight space. The work confirms
and extends recent studies by Siemion of amino acid conformational parameters.
The connections between the present work, and recent studies of the genetic
code structure using dynamical symmetry algebras, are pointed out.

</DOC>
<DOC>
<DOCNO> 118611 </DOCNO>
Analytic Light-Curves of Gamma-Ray Burst Afterglows: Homogeneous versus


  Assuming an adiabatic evolution of a Gamma-Ray Burst (GRB) remnant
interacting with an external medium, we calculate the injection, cooling, and
absorption break frequencies, and the afterglow flux for plausible orderings of
the break and observing frequencies. The analytical calculations are restricted
to a relativistic remnant and, in the case of collimated ejecta, to the phase
where there is an insignificant lateral expansion. Results are given for both a
homogeneous external medium and for a wind ejected by the GRB progenitor.
 We compare the afterglow emission at different observing frequencies, for each
type of external medium. It is found that observations at sub-millimeter
frequencies during the first day provide the best way of discriminating between
the two models. By taking into account the effect of inverse Compton
scatterings on the electron cooling, a new possible time-dependence of the
cooling break is identified. The signature of the up-scattering losses could be
seen in the optical synchrotron emission from a GRB remnant interacting with a
pre-ejected wind, as a temporary mild flattening of the afterglow decay. The
up-scattered radiation itself should be detected in the soft X-ray emission
from GRB remnants running into denser external media, starting few hours after
the main event.

</DOC>
<DOC>
<DOCNO> 150332 </DOCNO>
Quantization of fields over de Sitter space by the method of generalized


  A system of generalized coherent states for the de Sitter group obeying
Klein-Gordon equation and corresponding to the massive spin zero particles over
the de Sitter space is considered. This allows us to construct the quantized
scalar field by the resolution over these coherent states; the corresponding
propagator can be computed by the method of analytic continuation to the
complexified de Sitter space and coincides with expressions obtained previously
by other methods. We show that this propagator possess the de Sitter-invariance
and causality properties.

</DOC>
<DOC>
<DOCNO> 13342 </DOCNO>
First principles study of the origin and nature of ferromagnetism in


  The properties of diluted Ga$_{1-x}$Mn$_x$As are calculated for a wide range
of Mn concentrations within the local spin density approximation of density
functional theory. M\"ulliken population analyses and orbital-resolved
densities of states show that the configuration of Mn in GaAs is compatible
with either 3d$^5$ or 3d$^6$, however the occupation is not integer due to the
large $p$-$d$ hybridization between the Mn $d$ states and the valence band of
GaAs. The spin splitting of the conduction band of GaAs has a mean field-like
linear variation with the Mn concentration and indicates ferromagnetic coupling
with the Mn ions. In contrast the valence band is antiferromagnetically coupled
with the Mn impurities and the spin splitting is not linearly dependent on the
Mn concentration. This suggests that the mean field approximation breaks down
in the case of Mn-doped GaAs and corrections due to multiple scattering must be
considered. We calculate these corrections within a simple free electron model
and find good agreement with our {\it ab initio} results if a large exchange
constant ($N\beta=-4.5$eV) is assumed.

</DOC>
<DOC>
<DOCNO> 8660 </DOCNO>
What makes an insulator different from a metal?


  The insulating state of matter is characterized by the excitation spectrum,
but also by qualitative features of the electronic ground state. The insulating
ground wavefunction in fact: (i) displays vanishing dc conductivity; (ii)
sustains macroscopic polarization; and (iii) is localized. The idea that the
insulating state of matter is a consequence of electron localization was first
proposed in 1964 by W. Kohn. I discuss here a novel definition of electron
localization, rather different from Kohn's, and deeply rooted in the modern
theory of polarization. In fact the present approach links the two features
(ii) and (iii) above, by means of essentially the same formalism. In the
special case of an uncorrelated crystalline solid, the localization of the
many-body insulating wavefunction is measured - according to our definition -
by the spread of the Wannier orbitals; this spread diverges in the metallic
limit. In the correlated case, the novel approach to localization is
demonstrated by means of a two-band Hubbard model in one dimension, undergoing
a transition from band insulator to Mott insulator.

</DOC>
<DOC>
<DOCNO> 102288 </DOCNO>
Some characterizations of the automorphisms of $B(H)$ and $C(X)$


  We present some nonlinear characterizations of the automorphisms of the
operator algebra $B(H)$ and the function algebra $C(X)$ by means of their
spectrum preserving properties.

</DOC>
<DOC>
<DOCNO> 70788 </DOCNO>
Searching for the Higgs Boson at Hadron Colliders using the Missing Mass


  If the Higgs is produced with a large enough cross section in the {\em
exclusive} reaction $p + \bar{p} \to p + H + \bar{p}$ it will give rise to a
peak at $M_H$ in the {\em missing mass} ($MM$) spectrum, calculated from the
4-momenta of the beam particles and the outgoing $p$ and $\bar{p}$. The
resolution in $MM$ can be approximately 250 MeV, independent of $M_H$ from 100
GeV to 200 GeV. This high resolution makes a search feasible over nearly this
full mass range at the Tevatron with 15 fb$^{-1}$ as hoped for in Run II.

</DOC>
<DOC>
<DOCNO> 85626 </DOCNO>
Colliding black holes from a null point of view: the close limit


  We present a characteristic algorithm for computing the perturbations of a
Schwarzschild spacetime by means of solving the Teukolsky equations. Our
methods and results are expected to have direct bearing on the study of binary
black holes presently underway using a fully {\em nonlinear} characteristic
code \cite{Gomez98a}.

</DOC>
<DOC>
<DOCNO> 9284 </DOCNO>
The universality class of absorbing phase transitions with a conserved


  We investigate the critical behavior of systems exhibiting a continuous
absorbing phase transition in the presence of a conserved field coupled to the
order parameter. The results obtained point out the existence of a new
universality class of nonequilibrium phase transitions that characterizes a
vast set of systems including conserved threshold transfer processes and
stochastic sandpile models.

</DOC>
<DOC>
<DOCNO> 99561 </DOCNO>
The Alexander polynomial of a plane curve singularity and the ring of


  We give two formulae which express the Alexander polynomial $\Delta^C$ of
several variables of a plane curve singularity $C$ in terms of the ring ${\cal
O}_{C}$ of germs of analytic functions on the curve. One of them expresses
$\Delta^C$ in terms of dimensions of some factorspaces corresponding to a
(multi-indexed) filtration on the ring ${\cal O}_{C}$. The other one gives the
coefficients of the Alexander polynomial $\Delta^C$ as Euler characteristics of
some explicitly described spaces (complements to arrangements of projective
hyperplanes).

</DOC>
<DOC>
<DOCNO> 84659 </DOCNO>
Removal of interference from gravitational wave spectrum


  We develop a procedure to remove interference from gravitational wave
spectrum.
 The method is applied to the data produced by the Glasgow laser interferometer
in 1996 and all the lines corresponding to the interference with the main
supply are removed.

</DOC>
<DOC>
<DOCNO> 10671 </DOCNO>
Quantum and classical dynamics in complex one-dimensional


  Of great recent interest in condensed matter physics are phenomena of
coexistence of quantum and classical properties in the same material. Such
duality occurs in certain mixed-spin antiferromagnets composed of quantum spin
chains interacting through ``auxiliary'' magnetic ions. In this category are
linear-chain rare earth nickelates that exhibit a seemingly paradoxical
co-existence of long-range magnetic order and one-dimensional gapped quantum
spin excitations at low temperatures. In the present paper we propose a unified
physical description of these compounds, supported by recent neutron
diffraction and inelastic scattering studies. Our basic concept is the
effective separation between low-frequency classical and high-frequency quantum
spin correlations. This interpretation enables experimental measurements of
some previously inaccessible fundamental properties of quantum spin chains, and
predicts new exotic magnetic excitations and mechanisms of long-range ordering
in complex quantum magnets.

</DOC>
<DOC>
<DOCNO> 122477 </DOCNO>
Time Evolution of Cosmic-Ray Modified Plane Shocks


  We have developed a novel computer code designed to follow the evolution of
cosmic-ray modified shocks, including the full momentum dependence of the
particles for a realistic diffusion coefficient model. In this form the problem
is technically very difficult, because one needs to cover a wide range of
diffusive scales, beginning with those slightly larger than the physical shock
thickness. With most finite difference schemes for Euler's equations the
numerical shock thickness is at least one zone across, so this provides a lower
bound on the physical scale for diffusive transport computation. Our code uses
sub-zone shock tracking and multi-level adaptive mesh refinement to provide
enhanced spatial resolution around shocks at modest cost compared to the coarse
grid and vastly improved cost effectiveness compared to a uniform, highly
refined grid. We present and discuss the implications from our initial results.

</DOC>
<DOC>
<DOCNO> 70937 </DOCNO>
Measuring CP violation by low-energy medium-baseline neutrino


  In this talk we discuss the possibility to measure CP violation in neutrino
oscillation experiments using the neutrino beam with energy which is lower
(E_\nu \gsim 100 MeV) than the one usually considered (typically > 1 GeV) in
accelerator experiments. The advantage of using such lower energy neutrino beam
is that despite the smaller detection cross sections, the effect of CP
violation is larger and the optimal length of baseline can be rather short,
30-50 km, being free from matter effect contamination.

</DOC>
<DOC>
<DOCNO> 118335 </DOCNO>
Structural and Photometric Classification of Galaxies - I. Calibration


  In this paper we define an observationally robust, multi-parameter space for
the classification of nearby and distant galaxies. The parameters include
luminosity, color, and the image-structure parameters: size, image
concentration, asymmetry, and surface brightness. Based on an initial
calibration of this parameter space using the ``normal'' Hubble-types surveyed
by Frei et al. (1996), we find that only a subset of the parameters provide
useful classification boundaries for this sample. Interestingly, this subset
does not include distance-dependent scale parameters, such as size or
luminosity. The essential ingredient is the combination of a spectral index
(e.g., color) with parameters of image structure and scale: concentration,
asymmetry, and surface-brightness. We refer to the image structure parameters
(concentration and asymmetry) as indices of ``form.'' We define a preliminary
classification based on spectral index, form, and surface-brightness (a scale)
that successfully separates normal galaxies into three classes. We
intentionally identify these classes with the familiar labels of Early,
Intermediate, and Late. This classification, or others based on the above four
parameters can be used reliably to define comparable samples over a broad range
in redshift. The size and luminosity distribution of such samples will not be
biased by this selection process except through astrophysical correlations
between spectral index, form, and surface-brightness.

</DOC>
<DOC>
<DOCNO> 121655 </DOCNO>
Probing Planet Formation Among Nearby Young Stars


  The recent identification of several groups of young stars within 100 parsecs
of the Sun has generated widespread interest. Given their proximity and
possible age differences, these systems are ideally suited for detailed studies
of disk evolution and planet formation. Here I discuss recent results and
prospects for the near-future.

</DOC>
<DOC>
<DOCNO> 9249 </DOCNO>
Comment on: rotational properties of trapped bosons


  Based on the Hellman-Feynman theorem it is shown that the average square
radius of a cloud of interacting bosons in a parabolic well can be derived from
their free energy. As an application, the temperature dependence of the moment
of inertia of non-interacting bosons in a parabolic trap is determined as a
function of the number of bosons. Well below the critical condensation
temperature, the Bose-Einstein statistics are found to substantially reduce the
moment of inertia of this system, as compared to a gas of ``distinguishable''
particles in a parabolic well.

</DOC>
<DOC>
<DOCNO> 100515 </DOCNO>
Abelian extensions of algebras in congruence-modular varieties


  We define abelian extensions of algebras in congruence-modular varieties. The
theory is sufficiently general that it includes, in a natural way, extensions
of R-modules for a ring R. We also define a cohomology theory, which we call
clone cohomology, such that the cohomology group in dimension one is the group
of equivalence classes of extensions.

</DOC>
<DOC>
<DOCNO> 117731 </DOCNO>
A Natural Formalism for Microlensing


  If the standard microlensing geometry is inverted so that the Einstein ring
is projected onto the observer plane rather than the source plane, then the
relations between the observables (\theta_E,\tilde r_E) and the underlying
physical quantities (M,\pi_rel) become immediately obvious. Here \theta_E and
\tilde r_E are the angular and projected Einstein radii, M is the mass of the
lens, and \pi_rel is the lens-source relative parallax. I recast the basic
formalism of microlensing in light of this more natural geometry and in terms
of observables. I then find that the relations between observable and physical
quantities assume an exceptionally simple form. In an appendix, I propose a set
of notational conventions for microlensing.

</DOC>
<DOC>
<DOCNO> 169962 </DOCNO>
Control of tunneling by adapted signals


  Process of quantum tunneling of particles in various physical systems can be
effectively controlled even by a weak and slow varying in time electromagnetic
signal if to adapt specially its shape to a particular system. During an
under-barrier motion of a particle such signal provides a "coherent" assistance
of tunneling by the multi-quanta absorption resulting in a strong enhancement
of the tunneling probability. The semiclassical approach based on trajectories
in the complex time is developed for tunneling in a non-stationary field.
Enhancement of tunneling occurs when a singularity of the signal coincides in
position at the complex time plane with a singularity of the classical
Newtonian trajectory of the particle. The developed theory is also applicable
to the over-barrier reflection of particles and to reflection of classical
waves (electromagnetic, hydrodynamic, etc.) from a spatially-smooth medium.

</DOC>
<DOC>
<DOCNO> 7996 </DOCNO>
Exactly solvable statistical model for two-way traffic


  We generalize a recently introduced traffic model, where the statistical
weights are associated with whole trajectories, to the case of two-way flow. An
interaction between the two lanes is included which describes a slowing down
when two cars meet. This leads to two coupled five-vertex models. It is shown
that this problem can be solved by reducing it to two one-lane problems with
modified parameters. In contrast to stochastic models, jamming appears only for
very strong interaction between the lanes.

</DOC>
<DOC>
<DOCNO> 10955 </DOCNO>
rf susceptibility of La_{1-x}Sr_{x}MnO_{3} single crystals : magnetic


  A sensitive tunnel diode oscillator (TDO) operating at 4MHz is used to probe
the dynamic response of La_{1-x}Sr_{x}MnO_{3} single crystals for
x=0.125,0.175,0.28 and 0.33 doping. Systematics of the measured change in
reactance as a function of temperature (30K<T<320K) and DC magnetic field
(0<H<6kOe) reveal distinct temperature and field scales associated with the
dynamic response of spin. It is notable that these features are far more
striking than the corresponding features in static measurements. The results
are discussed in the context of structural changes leading to polaron ordering.

</DOC>
<DOC>
<DOCNO> 13587 </DOCNO>
Time-dependent screening of a positive charge distribution in metals:


  Experiments determining the lifetime of excited electrons in crystalline
copper reveal states which cannot be interpreted as Bloch states [S. Ogawa {\it
et al.}, Phys. Rev. B {\bf 55}, 10869 (1997)]. In this article we propose a
model which explains these states as transient excitonic states in metals. The
physical background of transient excitons is the finite time a system needs to
react to an external perturbation, in other words, the time which is needed to
build up a polarization cloud. This process can be probed with modern
ultra-short laser pulses. We calculate the time-dependent density-response
function within the jellium model and for real Cu. From this knowledge it is
possible within linear response theory to calculate the time needed to screen a
positive charge distribution and -- on top of this -- to determine excitonic
binding energies. Our results lead to the interpretation of the experimentally
detected states as transient excitonic states.

</DOC>
<DOC>
<DOCNO> 169821 </DOCNO>
Exact Solutions of the two-dimensional Schr\"{o}dinger equation with


  By applying an ansatz to the eigenfunction, an exact closed form solution of
the Schr\"{o}dinger equation in 2D is obtained with the potentials,
$V(r)=ar^2+br^4+cr^6$, $V(r)=ar+br^2+cr^{-1}$ and
$V(r)=ar^2+br^{-2}+cr^{-4}+dr^{-6}$, respectively. The restrictions on the
parameters of the given potential and the angular momentum $m$ are obtained.

</DOC>
<DOC>
<DOCNO> 116368 </DOCNO>
Explosion Implosion Duality and the Laboratory Simulation of


  The Euler equations of ideal gas dynamics posess a remarkable nonlinear
involutional symmetry which allows one to factor out an arbitrary uniform
expansion or contraction of the system. The nature of this symmetry (called by
cosmologists the transformation to supercomoving variables) is discussed and
its origin clarified. It is pointed out that this symmetry allows one to map an
explosion problem to a dual implosion problem and vice versa. The application
to laboratory simulations of supernova remnants is considered; in principle
this duality allows the complete three-dimensional evolution of highly
structured explosion ejecta to be modelled using a static target in an
implosion facility.

</DOC>
<DOC>
<DOCNO> 170117 </DOCNO>
A large-deviation type asymptotics in the quantum hypothesis testing


  This paper has been withdrawn by the author. Lemma 8 is used in the proof of
Lemma 6, but it is not correct. Lemma 6 is essential for the main results.

</DOC>
<DOC>
<DOCNO> 123304 </DOCNO>
Spectral Signature of Wind Generation From The Post-Shock Region in


  Accretion and outflows are common in systems which include black holes.
Especially important is the case of the well known micro-quasar GRS1915+105 in
our own galaxy, where super-luminal outflows are detected. We present a few
observation which are suggestive of an outflow which is generated very close to
the black hole, within a few tens of Schwarzschild radii. In the presence of
mass loss (e.g., an outflowing wind), the electron density of matter within the
centrifugal pressure supported region (which generates hard X-rays) goes down
and it is easier to cool these electrons by soft photons coming from the
Keplerian disk. If, on the other hand, the post-shock region gains mass from
outside, the spectra would be harder. These properties of spectral `softening'
of the low state and `hardening' of the high state have been detected in
several days of RXTE data of GRS1915+105 which we present here.

</DOC>
<DOC>
<DOCNO> 119775 </DOCNO>
The role of NCO reaction chain on the He ignition in degenerate stellar


  The role played by NCO reaction in the onset of the He flash in the He core
of a RGB star and in low mass CO WDs accreting H/He rich matter is
investigated.

</DOC>
<DOC>
<DOCNO> 13849 </DOCNO>
General pseudoadditivity of composable entropy prescribed by existence


  The concept of composability states that entropy of the total system composed
of independent subsystems is a function of entropies of the subsystems. Here,
the most general pseudoadditivity rule for composable entropy is derived based
only on existence of equilibrium.

</DOC>
<DOC>
<DOCNO> 71548 </DOCNO>
Lorentz Symmetry Violation and Acceleration in Relativistic Shocks


  In previous papers (e.g. physics/0003080 and references therein), it was
pointed out that Lorentz symmetry violation (LSV) at Planck scale can play a
crucial role in astrophysical processes at very high energy. It can potentially
inhibit radiation under external forces (e.g. synchrotron-like), GZK-like
cutoffs, decays, photodisintegration of nuclei, momentum loss trough collisions
(e.g. with a photon wind in reverse shocks), production of lower-energy
secondaries... An updated description of this phenomenon is presented, focusing
on acceleration in relativistic shocks and having in mind a model where the
effective parameter driving LSV would vary like the square of the momentum
scale (Quadratically Deformed Relativistic Kinematics, QDRK). Implications for
ultra-high energy (UHE) neutrino production are equally discussed.

</DOC>
<DOC>
<DOCNO> 13553 </DOCNO>
Polymer dynamics in time-dependent Matheron-de Marsily flows: An exactly


  We introduce a new model of random layered media, extending the Matheron-de
Marsily model: Here we allow for the flows to change in time. For such layered
structures, we solve exactly the equations of motion for single particles, and
also for polymers modelled as Rouse chains. The results show a rich variety of
dynamical patterns.

</DOC>
<DOC>
<DOCNO> 85167 </DOCNO>
Grazing Collisions of Black Holes via the Excision of Singularities


  We present the first simulations of non-headon (grazing) collisions of binary
black holes in which the black hole singularities have been excised from the
computational domain. Initially two equal mass black holes $m$ are separated a
distance $\approx10m$ and with impact parameter $\approx2m$. Initial data are
based on superposed, boosted (velocity $\approx0.5c$) solutions of single black
holes in Kerr-Schild coordinates. Both rotating and non-rotating black holes
are considered. The excised regions containing the singularities are specified
by following the dynamics of apparent horizons. Evolutions of up to $t \approx
35m$ are obtained in which two initially separate apparent horizons are present
for $t\approx3.8m$. At that time a single enveloping apparent horizon forms,
indicating that the holes have merged. Apparent horizon area estimates suggest
gravitational radiation of about 2.6% of the total mass. The evolutions end
after a moderate amount of time because of instabilities.

</DOC>
<DOC>
<DOCNO> 70803 </DOCNO>
Global three-neutrino oscillation analysis of neutrino data


  A global analysis of the solar, atmospheric and reactor neutrino data is
presented in terms of three-neutrino oscillations. We include the most recent
solar neutrino rates of Homestake, SAGE, GALLEX and GNO, as well as the recent
1117 day Super-Kamiokande data sample, including the recoil electron energy
spectrum both for day and night periods and we treat in a unified way the full
parameter space for oscillations, correctly accounting for the transition from
the matter enhanced (MSW) to the vacuum oscillations regime. Likewise, we
include in our description conversions with $\theta_{12} > \pi/4$. For the
atmospheric data we perform our analysis of the contained events and the
upward-going $\nu$-induced muon fluxes, including the previous data samples of
Frejus, IMB, Nusex, and Kamioka experiments as well as the full 71 kton-yr
(1144 days) Super-Kamiokande data set, the recent 5.1 kton-yr contained events
of Soudan2 and the results on upgoing muons from the MACRO detector. We first
present the allowed regions of solar and atmospheric oscillation parameters
$\theta_{12}$, $\Delta m^2_{21}$ and $\theta_{23}$, $\Delta m^2_{32}$,
respectively, as a function of $\theta_{13}$ and determine the constraints from
atmospheric and solar data on the mixing angle $\theta_{13}$, common to solar
and atmospheric analyses. We also obtain the allowed ranges of parameters from
the full five-dimensional combined analysis of the solar, atmospheric and
reactor data.

</DOC>
<DOC>
<DOCNO> 13457 </DOCNO>
Coexistence of large and small polarons in manganites


  The interplay of the electron-phonon interaction and of the double and super
exchange magnetic effects is analyzed in the $La_{1-x}Ca_xMnO_3$ perovskites
with $0<x<0.5$. By using an analytical variational scheme that allows to treat
the electron-phonon interaction in a fully quantum manner it is shown that in
the intermediate electron-phonon coupling regime a charge density instability
occurs near the metal-insulator transition, induced by either temperature or
hole doping. The system segregates in antiferromagnetic or paramagnetic small
polarons and ferromagnetic large polarons domains characterized by different
values of the lattice distortions that are satisfactory compared with those
experimentally observed.

</DOC>
<DOC>
<DOCNO> 100885 </DOCNO>
Geometric description of vakonomic and nonholonomic dynamics. Comparison


  We treat the vakonomic dynamics with general constraints within a new
geometric framework which will be appropriate to study optimal control
problems. We compare our formulation with Vershik-Gershkovich one in the case
of linear constraints. We show how nonholonomic mechanics also admits a new
geometrical description wich enables us to develop an algorithm of comparison
between the solutions of both dynamics. Some examples illustrating the theory
are treated.

</DOC>
<DOC>
<DOCNO> 9303 </DOCNO>
A periodic elastic medium in which periodicity is relevant


  We analyze, in both (1+1)- and (2+1)- dimensions, a periodic elastic medium
in which the periodicity is such that at long distances the behavior is always
in the random-substrate universality class. This contrasts with the models with
an additive periodic potential in which, according to the field theoretic
analysis of Bouchaud and Georges and more recently of Emig and Nattermann, the
random manifold class dominates at long distances in (1+1)- and
(2+1)-dimensions. The models we use are random-bond Ising interfaces in
hypercubic lattices. The exchange constants are random in a slab of size
$L^{d-1} \times \lambda$ and these coupling constants are periodically repeated
along either {10} or {11} (in (1+1)-dimensions) and {100} or {111} (in
(2+1)-dimensions). Exact ground-state calculations confirm scaling arguments
which predict that the surface roughness $w$ behaves as: $w \sim L^{2/3}, L \ll
L_c$ and $w \sim L^{1/2}, L \gg L_c$, with $L_c \sim \lambda^{3/2}$ in
$(1+1)$-dimensions and; $w \sim L^{0.42}, L \ll L_c$ and $w \sim \ln(L), L \gg
L_c$, with $L_c \sim \lambda^{2.38}$ in $(2+1)$-dimensions.

</DOC>
<DOC>
<DOCNO> 122339 </DOCNO>
The Relativistic Precession Model for QPOs in Low Mass X-ray Binaries


  The relativistic precession model for quasi periodic oscillations, QPOs, in
low mass X-ray binaries is reviewed. The behaviour of three simultaneous types
of QPOs is well matched in terms of the fundamental frequencies for geodesic
motion in the strong field of the accreting compact object for reasonable star
masses and spin frequencies. The model ascribes the higher frequency kHz QPOs,
the lower frequency kHz QPOs and the horizontal branch oscillations to the
Keplerian, periastron precession and nodal precession frequencies of matter
inhomogeneities orbiting close to the inner edge of the accretion disk. The
remarkable correlation between the centroid frequency of QPOs in both neutron
star and black hole candidate low mass X-ray binaries is very well fit by the
model. QPOs from low mass X-ray binaries might provide an unprecedented
laboratory to test general relativity in the strong field regime.

</DOC>
<DOC>
<DOCNO> 84783 </DOCNO>
Answer to the Comment about the Letter entitled ``Scalar fields as dark


  In this manuscript the authors present a detailed answer to the comment in
order to avoid misunderstandings in the future.

</DOC>
<DOC>
<DOCNO> 100360 </DOCNO>
Triangular dynamical r-matrices and quantization


  We provide a general study for triangular dynamical r-matrices using Poisson
geometry. We show that a triangular dynamical r-matrix always gives rise to a
regular Poisson manifold. Using the Fedosov method, we prove that
non-degenerate (i.e., the corresponding Poisson manifolds are symplectic)
triangular dynamical r-matrices (over $ \frakh^* $ and valued in
$\wedge^{2}\frakg$) are quantizable, and the quantization is classified by the
relative Lie algebra cohomology $H^{2}(\frakg, \frakh)[[\hbar ]]$. We also
generalize this quantization method to splittable triangular dynamical
r-matrices, which include all the known examples of triangular dynamical
r-matrices. Finally, we arrive a conjecture that the quantization for an
arbitrary triangular dynamical r-matrix is classified by the formal
neighbourhood of this r-matrix in the modular space of triangular dynamical
r-matrices. The dynamical r-matrix cohomology is introduced as a tool to
understand such a modular space.

</DOC>
<DOC>
<DOCNO> 121837 </DOCNO>
WFPC2 Observations of the Hubble Deep Field-South


  The Hubble Deep Field-South observations targeted a high-galactic-latitude
field near QSO J2233-606. We present WFPC2 observations of the field in four
wide bandpasses centered at roughly 300, 450, 606, and 814 nm. Observations,
data reduction procedures, and noise properties of the final images are
discussed in detail. A catalog of sources is presented, and the number counts
and color distributions of the galaxies are compared to a new catalog of the
HDF-N that has been constructed in an identical manner. The two fields are
qualitatively similar, with the galaxy number counts for the two fields
agreeing to within 20%. The HDF-S has more candidate Lyman-break galaxies at z
> 2 than the HDF-N. The star-formation rate per unit volume computed from the
HDF-S, based on the UV luminosity of high-redshift candidates, is a factor of
1.9 higher than from the HDF-N at z ~ 2.7, and a factor of 1.3 higher at z ~ 4.

</DOC>
<DOC>
<DOCNO> 119028 </DOCNO>
Keck Studies of M31's Stellar Halo


  We present Keck 10-meter/LRIS spectra of candidate red giants in the halo of
M31, located at a projected radius of R=19kpc on the minor axis. These
spectroscopic targets have been selected using a combination of UBRI-based and
morphological screening to eliminate background galaxies. Radial velocity
measurements are used to separate M31 halo giants from foreground Milky Way
dwarf stars, M31 disk stars, and residual background galaxies. The metallicity
of each M31 halo giant is measured using standard photometric and spectroscopic
techniques, the latter based on the strength of the CaII triplet. The various
[Fe/H] estimates are in rough agreement with one another. The data reveal a
large spread (>2dex) in [Fe/H] in M31's halo; there is no strong radial [Fe/H]
gradient. LRIS and HIRES spectra are also presented for red giants in five
dwarf spheroidal satellites of M31: AndI, AndIII, AndV, AndVI, and AndVII.
There appears to be a significant metallicity spread in AndVI and possibly in
AndI. The new radial velocity data on these outer dwarfs are used to constrain
the total mass of M31: the best estimate is under 10^(12)Msun, somewhat less
than the best estimate for the Milky Way.

</DOC>
<DOC>
<DOCNO> 123228 </DOCNO>
Probing the Stellar Surface of HD 209458 from Multicolor Transit


  Multicolor photometric observations of a planetary transit in the system HD
209458 are analyzed. The observations, made in the Stromgren photometric
system, allowed a recalculation of the basic physical properties of the
star-planet system. This includes derivation of linear limb-darkening values of
HD 209458, which is the first time that a limb-darkening sequence has
observationally been determined for a star other than the Sun. As the derived
physical properties depend on assumptions that are currently known with limited
precision only, scaling relations between derived parameters and assumptions
are given. The observed limb-darkening is in good agreement with theoretical
predictions from evolutionary stellar models combined with ATLAS model
atmospheres, verifying these models for the temperature (Teff ~ 6000K), surface
gravity (log g ~ 4.3) and mass (~ 1.2 Msol) of HD 209458.

</DOC>
<DOC>
<DOCNO> 68210 </DOCNO>
Anomalous triple and quartic gauge boson couplings


  This article reviews some recent developments in the analysis of anomalous
triple and quartic vector boson couplings that have been discussed at the UK
Phenomenology Workshop on Collider Physics 1999 in Durham.

</DOC>
<DOC>
<DOCNO> 83086 </DOCNO>
An Internet Multicast System for the Stock Market


  We are moving toward a distributed, international, twenty-four hour,
electronic stock exchange. The exchange will use the global Internet, or
internet technology. This system is a natural application of multicast because
there are a large number of receivers that should receive the same information
simultaneously.
  The data requirements for the stock exchange are discussed. The current
multicast protocols lack the reliability, fairness, and scalability needed in
this application. We describe a distributed architecture together with a
reliable multicast protocol, a modification of the RMP protocol, that has
characteristics appropriate for this application.
  The architecture is used in three applications: In the first, we construct a
unified stock ticker of the transactions that are being conducted on the
various physical and electronic exchanges. Our objective is to deliver the the
same combined ticker reliably and simultaneously to all receivers, anywhere in
the world. In the second, we construct a unified sequence of buy and sell
offers that are delivered to a single exchange or a collection of exchanges.
Our objective is to give all traders the same fair access to an exchange
independent of their relative distances to the exchange or the loss
characteristics of the international network. In the third, we construct a
distributed, electronic trading floor that can replace the current exchanges.
This application uses the innovations from the first two applications to
combine their fairness attributes.

</DOC>
<DOC>
<DOCNO> 151439 </DOCNO>
Measurability of Electromagnetic Field: Model and Path Integral Methods


  The problem of the measurability of the electromagnetic field is investigated
1) in the framework of the abstract restricted-path-integral method, and 2) by
explicitly accounting the action of the field onto the meter and its back
reaction. The meaning of the previously obtained results as well as of the
classical results of Bohr and Rosenfeld are made clear. The
restricted-path-integral method with integration over field configurations is
shown to give an estimation on the measurability of the field by any device not
disturbing the measured field (in the process of measurement) more than by the
measurement error. Such method of measurement is necessary for the control of
the field in electronic devices.

</DOC>
<DOC>
<DOCNO> 101163 </DOCNO>
Computing homomorphisms between holonomic D-modules


  Let K be a subfield of the complex numbers, and let D be the Weyl algebra of
K-linear differential operators on K[x_1,...,x_n]. If M and N are holonomic
left D-modules we present an algorithm that computes explicit generators for
the finite dimensional vector space hom_D(M,N). This enables us to answer
algorithmically whether two given holonomic modules are isomorphic. More
generally, our algorithm can be used to get explicit generators for
ext^i_D(M,N) for any i.

</DOC>
<DOC>
<DOCNO> 68805 </DOCNO>
Primordial magnetic fields from inflation?


  The hot plasma above the electroweak scale contains (hyper) charged scalar
particles which are coupled to Abelian gauge fields. Scalars may interact with
gravity in a non-conformally invariant way and thus their fluctuations can be
amplified during inflation. These fluctuations lead to creation of electric
currents and produce inhomogeneous distribution of charge density, resulting in
the generation of cosmological magnetic fields. We address the question whether
these fields can be coherent at large scales so that they may seed the galactic
magnetic fields. Depending upon the mass of the charged scalar and upon various
cosmological (critical fraction of energy density in matter, Hubble constant)
and particle physics parameters we found that the magnetic fields generated in
this way are much larger than vacuum fluctuations. However, their amplitude on
cosmological distances is found to be too small for seeding the galactic
magnetic fields.

</DOC>
<DOC>
<DOCNO> 40148 </DOCNO>
Latest Results of the KARMEN2 Experiment


  The neutrino experiment KARMEN at the beam stop neutrino source ISIS
investigates the oscillation channel numubar->nuebar in the appearance mode by
looking for p(nuebar,e+)n reactions. An analysis of data collected from
February 1997 through March 2000 with the KARMEN2 experimental setup reveals 11
candidate events in good agreement with the background expectation of 12.3+-0.6
events. Hence, there is no indication of an oscillation signal. A maximum
likelihood analysis of the data leads to an upper limit (at 90% confidence
level) for the mixing angle of sin^2(2theta) < 1.3x10^-3 at large Dm^2 and Dm^2
< 0.049 eV^2 for sin^2(2theta)=1. The anomaly in the time spectrum of events
induced by nue and numubar seen in the KARMEN1 data could not be confirmed with
the KARMEN2 data.

</DOC>
<DOC>
<DOCNO> 84886 </DOCNO>
Negative Norm States in de Sitter Space and QFT without Renormalization


  In a recent paper [1], it has been shown that the presence of negative norm
states are indispensable for a fully covariant quantization of the minimally
coupled scalar field in de Sitter space i.e. a new method of quantization).
Their presence, while leaving unchanged the physical content of the theory,
offers the advantage of eliminating any ultraviolet divergence in the vacuum
energy and infrared divergence in the two point function [1]. We attempt here
to extend this method, henceforth named Krein QFT, to the interacting quantum
field in Minkowski space-time. In Krein QFT, infrared and ultraviolet
divergences do not appear, which means the effect of these auxiliary negative
norm states in the physics of the problem is to allow an automatic
renormalization of the theory. As an illustration of the procedure, we consider
the $\lambda\phi^4$ theory in Minkowski space-time.

</DOC>
<DOC>
<DOCNO> 170652 </DOCNO>
Non-Markovian homodyne-mediated feedback on a two-level atom: a quantum


  Quantum feedback can stabilize a two-level atom against decoherence
(spontaneous emission), putting it into an arbitrary (specified) pure state.
This requires perfect homodyne detection of the atomic emission, and
instantaneous feedback. Inefficient detection was considered previously by two
of us. Here we allow for a non-zero delay time $\tau$ in the feedback circuit.
Because a two-level atom is a nonlinear optical system, an analytical solution
is not possible. However, quantum trajectories allow a simple numerical
simulation of the resulting non-Markovian process. We find the effect of the
time delay to be qualitatively similar to that of inefficient detection. The
solution of the non-Markovian quantum trajectory will not remain fixed, so that
the time-averaged state will be mixed, not pure. In the case where one tries to
stabilize the atom in the excited state, an approximate analytical solution to
the quantum trajectory is possible. The result, that the purity ($P=2{\rm
Tr}[\rho^{2}]-1$) of the average state is given by $P=1-4\gamma\tau$ (where
$\gamma$ is the spontaneous emission rate) is found to agree very well with the
numerical results.

</DOC>
<DOC>
<DOCNO> 71054 </DOCNO>
Partonic structure of $\gamma_L^*$ in hard collisions


  Manifestation of QCD improved partonic structure of longitudinally polarized
virtual photons in hard collisions is discussed. As an example, dijet
production in ep collisions at HERA is investigated in detail.

</DOC>
<DOC>
<DOCNO> 170488 </DOCNO>
Nash Equilibrium in the Quantum Battle of Sexes Game


  We investigate Nash Equilibrium in the quantum Battle of Sexes Game. We find
the game has infinite Nash Equilibria and all of them leads to the asymmetry
result. We also show that there is no unique but infinite Nash Equilibrium in
it if we use the quantizing scheme proposed by Eisert et al and the two players
are allowed to adopt any unitary operator as his/her strategies.

</DOC>
<DOC>
<DOCNO> 118978 </DOCNO>
Short term pulse frequency fluctuations of OAO 1657-415 from RXTE


  We present new X-ray observations of the high mass X-ray binary (HMXRB)
pulsar OAO 1657-415, obtained during one orbital period (10.44 days) with the
Rossi X-Ray Timing Explorer (RXTE). Using the binary orbital parameters,
obtained from Burst and Transient Source Experiment (BATSE) observations, we
resolve the fluctuations in the pulse frequency at time scales on the order of
one day for the first time. Recent BATSE results showed that OAO 1657-415 has
spin-up/down trends in its pulse frequency time series, without any correlation
with the X-luminosity at energies $>$20 keV (Baykal 1997). In the present RXTE
observations the source is found to be in an extended phase of spin-down. We
also find a gradual increase in the X-ray luminosity which is correlated with a
marginal spin-up episode. The marginal correlation between the gradual spin-up
(or decrease in spin-down rate) and increase in X-ray luminosity suggests that
the OAO 1657-415 is observed during a stable accretion episode where the
prograde accretion disk is formed.

</DOC>
<DOC>
<DOCNO> 117619 </DOCNO>
Predicting caustic crossing high magnification events in Q2237+0305


  The central regions of the gravitationally lensed quasar Q2237+0305 can be
indirectly resolved on nano-arcsecond scales if viewed spectrophotometricly
during a microlensing high magnification event (HME). Q2237+0305 is currently
being monitored from the ground (eg. OGLE collaboration, Apache Point
Observatory), with the goal, among others, of triggering ground and spacecraft
based target of opportunity (TOO) observations of an HME. In this work we
investigate the rate of change (trigger) in image brightness that signals an
imminent HME and importantly, the separation between the trigger and the event
peak. In addition, we produce colour dependent model light-curves by combining
high-resolution microlensing simulations with a realistic model for a thermal
accretion disc source. We make hypothetical target of opportunity spectroscopic
observations using our determination of the appropriate trigger as a guide. We
find that if the source spectrum varies with source radius, a 3 observation TOO
program should be able to observe a microlensing change in the continuum slope
following a light-curve trigger with a success rate of >80%.

</DOC>
<DOC>
<DOCNO> 13402 </DOCNO>
Explaining critical angular velocities of the vortex formation in a


  The problem of explanation of the critical angular velocity $\Omega_c$ when
the formation of a vortex in the stirred Bose-Einstein condensate becomes
energetically possible, is considered in the framework of the variational
approach. The origin of smallness of the calculated $\Omega_c$ in comparison
with the measured values which takes place for pure quantum state with the unit
angular momentum per condensed particle, is uncovered. The agreement with the
measured $\Omega_c$ is achieved upon admitting a small admixture of the zero
angular momentum state in the wave function of the one-vortex quantum state
prepared after stirring. The portion of this admixture amounts to 10 - 13 % of
the total condensed atoms. Possible test of this hypothesis is proposed.

</DOC>
<DOC>
<DOCNO> 71131 </DOCNO>
Constraints on Gauged B-3L_tau and Related Theories


  We consider extensions of the Standard Model with an extra U(1) gauge boson
which couples to B-(alpha L_e + beta L_mu + gamma L_tau) with alpha + beta +
gamma = 3. We show that the extra gauge boson necessarily mixes with the Z
leading to potentially significant corrections to the Z-f-fbar vertex. The
constraints on the size of this correction imposed by the Z-pole data from LEP
and SLD are derived.

</DOC>
<DOC>
<DOCNO> 71041 </DOCNO>
Lattice regularization for chiral perturbation theory


  The SU(3) chiral lagrangian for the lightest octets of mesons and baryons is
constructed on a spacetime lattice. The lattice spacing acts as an ultraviolet
momentum cutoff which appears directly in the Lagrangian so chiral symmetry
remains explicit. As the lattice spacing vanishes, Feynman loop diagrams
typically become divergent due to inverse powers of the lattice spacing, and
these divergences get absorbed into counterterms such that the standard results
of dimensional regularization are obtained. One advantage of lattice
regularization is that power divergences are seen explicitly. In the present
work, the octet meson masses, the octet baryon masses and the pion-nucleon
sigma term are all computed explicitly to one loop order.

</DOC>
<DOC>
<DOCNO> 102912 </DOCNO>
Hopf solitons and area preserving diffeomorphisms of the sphere


  We consider a (3+1)-dimensional local field theory defined on the sphere. The
model possesses exact soliton solutions with non trivial Hopf topological
charges, and infinite number of local conserved currents. We show that the
Poisson bracket algebra of the corresponding charges is isomorphic to that of
the area preserving diffeomorphisms of the sphere. We also show that the
conserved currents under consideration are the Noether currents associated to
the invariance of the Lagrangian under that infinite group of diffeomorphisms.
We indicate possible generalizations of the model.

</DOC>
<DOC>
<DOCNO> 99549 </DOCNO>
The LMO-invariant of 3-manifolds of rank one and the Alexander


  We prove that the LMO-invariant of a 3-manifold of rank one is determined by
the Alexander polynomial of the manifold, and conversely, that the Alexander
polynomial is determined by the LMO-invariant. Furthermore, we show that the
Alexander polynomial of a null-homologous knot in a rational homology 3-sphere
can be obtained by composing the weight system of the Alexander polynomial with
the Aarhus invariant of knots.

</DOC>
<DOC>
<DOCNO> 170659 </DOCNO>
Diese verdammte quantenspringerei


  It is argued that the conventional formulation of quantum mechanics is
inadequate: the usual interpretation of the mathematical formalism in terms of
the results of measurements cannot be applied to situations in which
discontinuous transitions ("quantum jumps) are observed as they happen, since
nothing that can be called a measurement happens at the moment of observation.
Attempts to force such observations into the standard mould lead to absurd
results: "a watched pot never boils". Experiments show both that this result is
correct when the experiment does indeed consist of a series of measurements,
and that it is not when the experiment consists of a period of observation:
quantum jumps do happen. The possibilities for improving the formalism by
incorporating transitions in the basic postulates are reviewed, and a
satisfactory postulate is obtained by modifying a suggestion of Bell's. This
requires a distinction between the external description of the whole of a
physical system and internal descriptions which are themselves physical events
in the system. It is shown that this gives correct results for simple unstable
systems and for the quantum-jump experiments.

</DOC>
<DOC>
<DOCNO> 71357 </DOCNO>
Topics in the Heavy Quark Expansion


  Achievements in the heavy quark theory over the last decade are reviewed,
with the main emphasis put on dynamical methods which quantify nonperturbative
effects via application of the Operator Product Expansion. These include the
total weak decay rates of heavy flavor hadrons and nonperturbative corrections
to heavy quark sum rules. Two new exact superconvergent sum rules are derived;
they differ from the known ones in that they are finite and normalization point
independent in perturbation theory. A new hadronic parameter \bar\Sigma is
introduced which is a spin-nonsinglet analogue of \bar\Lambda=M_B-m_b; it is
expected to be about 0.25GeV. The first sum rule implies the bound \rho^2 > 3/4
for the slope of the Isgur-Wise function. The heavy quark potential is
discussed and its connection to the infrared contributions in the heavy quark
mass. Among applications extraction of |V_cb| from the total semileptonic and
from the B->D^* zero recoil rates is addressed, as well as extracting |V_ub|
from \Gamma_sl(b->u). Practical aspects of local quark-hadron duality are
briefly discussed.

</DOC>
<DOC>
<DOCNO> 123233 </DOCNO>
Pulsar wind nebulae in supernova remnants


  A spherically symmetric model is presented for the interaction of a pulsar
wind with the associated supernova remnant. This results in a pulsar wind
nebula whose evolution is coupled to the evolution of the surrounding supernova
remnant. This evolution can be divided in three stages. The first stage is
characterised by a supersonic expansion of the pulsar wind nebula into the
freely expanding ejecta of the progenitor star. In the next stage the pulsar
wind nebula is not steady; the pulsar wind nebula oscillates between
contraction and expansion due to interaction with the reverse shock of the
supernova remnant: reverberations which propagate forward and backward in the
remnant. After the reverberations of the reverse shock have almost completely
vanished and the supernova remnant has relaxed to a Sedov solution, the
expansion of the pulsar wind nebula proceeds subsonically. In this paper we
present results from hydrodynamical simulations of a pulsar wind nebula through
all these stages in its evolution. The simulations were carried out with the
Versatile Advection Code.

</DOC>
<DOC>
<DOCNO> 40481 </DOCNO>
Results on B to Charmonia Decays from CLEO


  We review some recent results on B to charmonia decays from CLEO based on 9.7
BBbar pairs collected with the CLEO detector. These include measurements of
B^{0} to J\Psi K^0_s, \chi_{c1} K^0_s and J/\Psi \pi^0 branching fractions,
search for direct CP violation in B^{\pm} to J/\Psi K^\pm and \Psi(2S) K^\pm,
observation of B \to \eta_{c} K, study of \chi_{c1}, \chi_{c2} production and
measurement of the relative branching fraction of \Upsilon(4S) to charged and
neutral B meson pairs.

</DOC>
<DOC>
<DOCNO> 39694 </DOCNO>
Discovering a Light Higgs Boson with Light


  We evaluate the prospects for detecting a non-standard light Higgs boson with
a significant branching ratio to two photons, in Run II of the Fermilab
Tevatron. We derive the reach for several channels: $2\gamma$ inclusive,
$2\gamma+1$ jet and $2\gamma+2$ jets. We present the expected Run II limits on
the branching ratio of $h\to\gamma\gamma$ as a function of the Higgs mass, for
the case of ``bosonic'', as well as ``topcolor'' Higgs bosons.

</DOC>
<DOC>
<DOCNO> 84890 </DOCNO>
Spaces with contravariant and covariant affine connections and metrics


  The theory of spaces with different (not only by sign) contravariant and
covariant affine connections and metrics [}$(\bar{L}_n,g)$\QTR{it}{-spaces] is
worked out within the framework of the tensor analysis over differentiable
manifolds and in a volume necessary for the further considerations of the
kinematics of vector fields and the Lagrangian theory of tensor fields
over}$(\bar{L}_n,g)$\QTR{it}{-spaces. The possibility of introducing affine
connections (whose components differ not only by sign) for contravariant and
covariant tensor fields over differentiable manifolds with finite dimensions is
discussed. The action of the deviation operator, having an important role for
deviation equations in gravitational physics, is considered for the case of
contravariant and covariant vector fields over differentiable manifolds with
different affine connections A deviation identity for contravariant vector
fields is obtained. The notions covariant, contravariant, covariant projective,
and contravariant projective metrics are introduced in
(}$\bar{L}_n,g$\{)-spaces. The action of the covariant and the Lie differential
operators on the different type of metrics is found. The notions of symmetric
covariant and contravariant (Riemannian) connections are determined and
presented by means of the covariant and contravariant metrics and the
corresponding torsion tensors. The different types of relative tensor fields
(tensor densities) as well as the invariant differential operators acting on
them are considered. The invariant volume element and its properties under the
action of different differential operators are investigated.

</DOC>
<DOC>
<DOCNO> 99889 </DOCNO>
Statement of the Alexandru Conjecture


  The Vogan Conjectures (sometimes called Kazhdan-Lusztig Conjectures) say that
a certain algorithm works both on the category of BGG modules and on the
category of Harish-Chandra modules. The Alexandru Conjecture tries to uncover
the general property common to these two categories which makes Vogan's
algorithm work.

</DOC>
<DOC>
<DOCNO> 13547 </DOCNO>
Magnetic field dependence of the critical current of tridimensional


  In this paper we determine the magnetic field dependence of the critical
current of a tridimensional disordered Josephson junction array (3D-DJJA). A
contactless configuration, employing measurements of the AC-susceptibility, is
used to evaluate the average critical current of an array of YBa2Cu3O7-x. The
critical field necessary to switch off supercurrents through the weak links at
the working temperature is also obtained.

</DOC>
<DOC>
<DOCNO> 7862 </DOCNO>
D-XY Critical Behavior in Cuprate Superconductors


  We outline the universal and finite temperature critical properties of the
3D-XY model, extended to anisotropic extreme type-II superconductors, as well
as the universal quantum critical properties in 2D. On this basis we review:
(i) the mounting evidence for 3D-XY behavior in optimally doped cuprate
superconductors and the 3D to 2D crossover in the underdoped regime; (ii) the
finite size limitations imposed by inhomogeneities; (iii) the experimental
evidence for a 2D-XY quantum critical point in the underdoped limit, where the
superconductor to insulator transition occurs; (iv) the emerging implications
and constraints for microscopic models.

</DOC>
<DOC>
<DOCNO> 11794 </DOCNO>
Quantum Number Fractionization in Cuprates: U(1) RVB Gauge Theory and


  We critically look at Senthil Fisher constructions of quantum number
fractionization in cuprates. The first construction, while mathematically
correct is of limited relevance to cuprates. The second one has a missing local
U(1) symmetry. Once this aspect is repaired, it reveals itself as the U(1) RVB
gauge theory construction of quantum number fractionization. An approximate
local $Z_2$ symmetry arises in the spin sector for a reason very different from
Senthil and Fisher's. The charge sector continues to have the local U(1)
symmetry and the metallic spin gap phase of the 2d cuprates may, in principle,
carry (irrational) fractional charge $e^* \neq e$ obeying Haldane's fractional
exclusion statistics like the 1d models.

</DOC>
<DOC>
<DOCNO> 99783 </DOCNO>
Null-geodesics in complex conformal manifolds and the LeBrun


  In the complex-Riemannian framework we show that a conformal manifold
containing a compact, simply-connected, null-geodesic is conformally flat. In
dimension 3 we use the LeBrun correspondence, that views a conformal 3-manifold
as the conformal infinity of a selfdual four-manifolds. We also find a relation
between the conformal invariants of the conformal infinity and its ambient.

</DOC>
<DOC>
<DOCNO> 71587 </DOCNO>
Minimal Superstring Standard Model: A Review


  I review a heterotic-string solution in which the observable sector effective
field theory just below the string scale reduces to that of the MSSM, with the
standard observable gauge group being just SU(3)_C x SU(2)_L x U(1)_Y and the
SU(3)_C x SU(2)_L x U(1)_Y-charged spectrum of the observable sector consisting
solely of the MSSM spectrum. Associated with this model is a set of distinct
flat directions of vacuum expectation values (VEVs) of fields that all produce
solely the MSSM spectrum. Some of these directions only involve VEVs of
non-Abelian singlet fields while others also contain VEVs of non-Abelian
charged fields. The phenomenology of theses flat directions is summarized.

</DOC>
<DOC>
<DOCNO> 85371 </DOCNO>
Gravitational reaction force on a particle in the Schwarzschild


  We formulate a new method to calculate the gravitational reaction force on a
particle of mass $\mu$ orbiting a massive black hole of mass $M$. In this
formalism, the tail part of the retarded Green function, which is responsible
for the reaction force, is calculated at the level of the Teukolsky equation.
Our method naturally allows a systematic post-Minkowskian (PM) expansion of the
tail part at short distances. As a first step, we consider the case of a
Schwarzschild black hole and explicitly calculate the first post-Newtonian
(1PN) tail part of the Green function. There are, however, a couple of issues
to be resolved before explicitly evaluating the reaction force by applying the
present method. We discuss possible resolutions of these issues.

</DOC>
<DOC>
<DOCNO> 83279 </DOCNO>
Entropy-based Pruning of Backoff Language Models


  A criterion for pruning parameters from N-gram backoff language models is
developed, based on the relative entropy between the original and the pruned
model. It is shown that the relative entropy resulting from pruning a single
N-gram can be computed exactly and efficiently for backoff models. The relative
entropy measure can be expressed as a relative change in training set
perplexity. This leads to a simple pruning criterion whereby all N-grams that
change perplexity by less than a threshold are removed from the model.
Experiments show that a production-quality Hub4 LM can be reduced to 26% its
original size without increasing recognition error. We also compare the
approach to a heuristic pruning criterion by Seymore and Rosenfeld (1996), and
show that their approach can be interpreted as an approximation to the relative
entropy criterion. Experimentally, both approaches select similar sets of
N-grams (about 85% overlap), with the exact relative entropy criterion giving
marginally better performance.

</DOC>
<DOC>
<DOCNO> 11467 </DOCNO>
Bulk Flow Regimes and Fractional Flow in 2D Porous Media by Numerical


  We investigate a two-dimensional network simulator that model the dynamics of
two-phase immiscible bulk flow where film flow can be neglected. We present a
method for simulating the detailed dynamical process where the two phases are
allowed to break up into bubbles, and bubbles are allowed to merge together.
The notions of drainage and imbibition are not adequate to describe this
process since there is no clear front between the fluids. In fact, the
simulator is constructed so that one can study the behaviour of the system far
from inlets and outlets, where the two fluids have been mixed together so much
that all initial fronts have broken up. The simulator gives the fractional flow
as a function of the saturation of each of the fluids. For the case of two
fluids with equal viscosity, we classify flow regimes that are parametrized by
the capillary number.

</DOC>
<DOC>
<DOCNO> 12722 </DOCNO>
Proposal of an extended t-J Hamiltonian for high-Tc cuprates from ab


  A series of accurate ab initio calculations on Cu_pO-q finite clusters,
properly embedded on the Madelung potential of the infinite lattice, have been
performed in order to determine the local effective interactions in the CuO_2
planes of La_{2-x}Sr_xCuO_4 compounds. The values of the first-neighbor
interactions, magnetic coupling (J_{NN}=125 meV) and hopping integral
(t_{NN}=-555 meV), have been confirmed. Important additional effects are
evidenced, concerning essentially the second-neighbor hopping integral
t_{NNN}=+110meV, the displacement of a singlet toward an adjacent colinear
hole, h_{SD}^{abc}=-80 meV, a non-negligible hole-hole repulsion
V_{NN}-V_{NNN}=0.8 eV and a strong anisotropic effect of the presence of an
adjacent hole on the values of the first-neighbor interactions. The dependence
of J_{NN} and t_{NN} on the position of neighbor hole(s) has been rationalized
from the two-band model and checked from a series of additional ab initio
calculations. An extended t-J model Hamiltonian has been proposed on the basis
of these results. It is argued that the here-proposed three-body effects may
play a role in the charge/spin separation observed in these compounds, that is,
in the formation and dynamic of stripes.

</DOC>
<DOC>
<DOCNO> 12264 </DOCNO>
Thermal metal in network models of a disordered two-dimensional


  We study the universality class for localization which arises from models of
non-interacting quasiparticles in disordered superconductors that have neither
time-reversal nor spin-rotation symmetries. Two-dimensional systems in this
category, which is known as class D, can display phases with three different
types of quasiparticle dynamics: metallic, localized, or with a quantized
(thermal) Hall conductance. Correspondingly, they can show a variety of
delocalization transitions. We illustrate this behavior by investigating
numerically the phase diagrams of network models with the appropriate symmetry,
and for the first time show the appearance of the metallic phase.

</DOC>
<DOC>
<DOCNO> 152397 </DOCNO>
N = 2 Gauge/Gravity Duals


  We study the N = 2 supersymmetric analog of the Klebanov-Strassler system. We
first review the resolution of singularities by the enhancon mechanism, and the
physics of fractional branes on an orbifold. We then describe the exact N = 2
solution. This exhibits a duality cascade as in the N = 1 case, but the
singularity resolution is the characteristic N = 2 enhancon. We discuss some
related solutions and open issues.

</DOC>
<DOC>
<DOCNO> 118691 </DOCNO>
The dynamical evolution of the fragmented, bipolar dust shell around the


  We present high-resolution J-, H-, and K-band observations and the first H-K
color image of the carbon star IRC +10216. The images were reconstructed from
6m telescope speckle interferograms using the bispectrum speckle interferometry
method. The H and K images with resolutions between 70mas and 92mas consist of
several compact components within a 0.2" radius and a fainter asymmetric
nebula. The brightest four components are denoted with A to D in the order of
decreasing brightness in the 1996 image. A comparison of our images from 1995,
1996, 1997, and 1998 gives - almost like a movie of five frames - insight into
the dynamical evolution of the inner nebula. For instance, the separation of
the two brightest components A and B increased from 191 mas in 1995 to 265 mas
in 1998. At the same time, component B is fading and the components C and D
become brighter. The X-shaped bipolar structure of the nebula, most prominently
present in the J-band image, implies an asymmetric mass loss. Such asymmetries
are often present in protoplanetary nebulae but are unexpected for AGB stars.
IRC +10216 is thus likely to be very advanced in its AGB evolution, shortly
before turning into a protoplanetary nebula. The cometary shapes of A in the H
and J images and in the 0.79 micron and 1.06 micron HST images suggest that the
core of A is not the central star, but the southern lobe of a bipolar
structure. The position of the central star is probably at or near the position
of component B, where the H-K color has a value of 4.2. If the star is at or
near B, then the components A, C, and D are likely to be located at the inner
boundary of the dust shell.

</DOC>
<DOC>
<DOCNO> 178920 </DOCNO>
$\sigma$ Exchange in the NN Interaction within the Chiral Unitary


  We study the nucleon-nucleon interaction in the isoscalar-scalar channel
using t he chiral unitary approach. The $t$-matrix of the pion-pion scattering
in this c hannel is summed up to all orders using the B-S equation. We find
that the calcu lated results at long distances are close to those of the
$\sigma$-exchange inte raction. In addition, there appears a shorter range
repulsion in this channel.

</DOC>
<DOC>
<DOCNO> 40127 </DOCNO>
On the Structure of the Proton, the Photon, and Colour Singlet Exchange


  Structure function measurements of the proton, the photon, and of colour
singlet exchange are analysed using fits based on logarithmic Q**2-dependence.
The fits reveal the x-dependencies of the hadronic structures and the
interaction dynamics as directed by the data.

</DOC>
<DOC>
<DOCNO> 118575 </DOCNO>
Detection of new sources of methanol emission at 95 GHz with the Mopra


  A southern hemisphere survey of methanol emission sources has been carried
out using the ATNF Mopra millimetre telescope. 85 sources, the majority of them
masers, have been detected in the 8(0)-7(1)A+ transition of methanol at 95 GHz.
Together with a similar northern hemisphere survey this completes the search
for 95-GHz methanol emission from the Galactic Plane. The previously found
correlation between intensity of methanol emission at 44 and 95 GHz is
confirmed here with the larger sample of sources. The results of LVG
statistical equilibrium calculations confirm the classification of these
sources as class I methanol masers pumped through collisional excitation.

</DOC>
<DOC>
<DOCNO> 70731 </DOCNO>
New effective treatment of the light-front nonvalence contribution in


  We discuss a necessary nonvalence contribution in timelike exclusive
processes. Following a Schwinger-Dyson type of approach, we relate the
nonvalence contribution to an ordinary light-front wave function that has been
extensively tested in the spacelike exclusive processes. A complicate four-body
energy denominator is exactly cancelled in summing the light-front time-ordered
amplitudes. Applying our method to $K_{\ell3}$ and $D^0\to K^- \ell^+ \nu_l$
where a rather substantial nonvalence contribution is expected, we find not
only an improvement in comparing with the experimental data but also a
covariance(i.e. frame-independence) of existing light-front constituent quark
model.

</DOC>
<DOC>
<DOCNO> 9390 </DOCNO>
High Temperature Superconducting Radio Frequency Coils for NMR


  High-temperature superconductivity has a significant opportunity to improve
the performance of nuclear magnetic resonance (NMR) spectroscopy and magnetic
resonance imaging (MRI) systems. The low rf losses and low operating
temperatures of superconducting coils allow them to improve the signal-to-noise
ratio in applications where the system noise dominates that of the sample under
study. These improvements translate into new capabilities and shorter
measurement times for NMR and MRI systems. In this pedagogical paper, we
discuss the implementation and impact of high-T$_c$ superconducting thin films
in rf coils for NMR and MRI applications.

</DOC>
<DOC>
<DOCNO> 99512 </DOCNO>
Generalized Hopfian property, minimal Haken manifold, and J. Simon's


  We address a conjecture that $\pi_1$-surjective maps between closed
aspherical 3-manifolds having the same rank on $\pi_1$ must be of non-zero
degree. The conjecture is proved for Seifert manifolds, which is used in
constructing the first known example of minimum Haken manifold. Another
motivation is to study epimorphisms of 3-manifold groups via maps of non-zero
degree between 3-manifolds.

</DOC>
<DOC>
<DOCNO> 8557 </DOCNO>
Ice XII in its second regime of metastability


  We present neutron powder diffraction results which give unambiguous evidence
for the formation of the recently identified new crystalline ice phase[Lobban
et al.,Nature, 391, 268, (1998)], labeled ice XII, at completely different
conditions. Ice XII is produced here by compressing hexagonal ice I_h at T =
77, 100, 140 and 160 K up to 1.8 GPa. It can be maintained at ambient pressure
in the temperature range 1.5 < T < 135 K. High resolution diffraction is
carried out at T = 1.5 K and ambient pressure on ice XII and accurate
structural properties are obtained from Rietveld refinement. At T = 140 and 160
K additionally ice III/IX is formed. The increasing amount of ice III/IX with
increasing temperature gives an upper limit of T ~ 150 K for the successful
formation of ice XII with the presented procedure.

</DOC>
<DOC>
<DOCNO> 10813 </DOCNO>
Forecasting price increments using an artificial Neural Network


  Financial forecasting is a difficult task due to the intrinsic complexity of
the financial system. In the present paper we relate our experience using
neural nets as financial time series forecast method. In particular we show
that a neural net able to forecast the sign of the price increments with a
success rate slightly above 50 percent can be found.

</DOC>
<DOC>
<DOCNO> 12350 </DOCNO>
Phase Space Reduction and the Instanton Crossover in (1+1)-Dimensional


  We study (1+1)-dimensional turbulence in the framework of the
Martin-Siggia-Rose field theory formalism. The analysis is focused on the
asymptotic behaviour at the right tail of the probability distribution function
(pdf) of velocity differences, where shock waves do not contribute. A
BRS-preserving scheme of phase space reduction, based on the smoothness of the
relevant velocity fields, leads to an effective theory for a few degrees of
freedom. The sum over fluctuations around the instanton solution is written as
the expectation value of a functional of the time-dependent physical fields,
which evolve according to a set of Langevin equations. A natural regularization
of the fluctuation determinant is provided from the fact that the instanton
dominates the action for a finite time interval. The transition from the
turbulent to the instanton dominated regime is related to logarithmic
corrections to the saddle-point action, manifested on their turn as
multiplicative power law corrections to the velocity differences pdf.

</DOC>
<DOC>
<DOCNO> 122969 </DOCNO>
Chaotic Inflation with Variable Space Dimensions


  Assuming the space dimension is not constant but decreases during the
expansion of the Universe, we study chaotic inflation with the potential $m^2
\phi^2/2$. We write down field equations in the slow-roll approximation and
define slow -roll parameters by assuming the space dimension to be a dynamical
parameter. The dynamical character of the space dimension shifts the initial
and final value of the inflaton field to larger values, producing delayed
chaotic inflation. We obtain an upper limit for the space dimension at the
Planck length. This result is in agreement with previous works on the effective
time variation of the Newtonian gravitational constant in a model Universe with
variable space dimensions. We present some cosmological consequences and
calculate observable quantities including the spectral indices, their
scale-dependence, and the mass of the inflaton field.

</DOC>
<DOC>
<DOCNO> 11098 </DOCNO>
The Distribution of Multiple Energy Minima and Hysteresis in Zero


  The Random Field Ising Model (RFIM) is the simplest physical model reflecting
effect of quenched disorder on the different types of phase transitions in
solids. The presence of multiple energy minima in the RFIM is an important
feature determining main physical properties of the systems with a field type
of quenched disorder. In particular, according to computer simulations of
Sethna at al. performed for a zero temperature RFIM, the irreversible loop of
magnetization appears as direct result of their presence. In the present paper
the analytic method based on the total number of energy minima estimation is
developed to study the hysteretic behavior of a zero temperature RFIM. As a
result, the magnetization hysteresis loop is obtained as a marginal curve
separating metastable and completely unstable states in the
magnetization-external field plane.

</DOC>
<DOC>
<DOCNO> 71697 </DOCNO>
Can large fermion chemical potentials suppress the electroweak phase


  We calculate the critical temperature $(T_c$) of the electroweak phase
transition in the minimal standard model considering simultaneously temperature
($T$) and fermion chemical potential ($\mu_f$) effects over the effective
potential. The calculation is performed in the one-loop approximation to the
effective potential at non-zero temperature using the real time formalism of
the thermal field theory. We show that it exists a fermion chemical potential
critical value ($\mu_f^c$) for which the Higgs boson condensate vanishes at
T=0. If $T$ and $\mu_f$ effects are considered simultaneously, it is shown that
for $\mu_f \geq \mu_f^c$ then $T_c^2 \leq 0$, implying that the electroweak
phase transition might not take place.

</DOC>
<DOC>
<DOCNO> 100092 </DOCNO>
Navier-Stokes equations and fluid turbulence


  An Eulerian-Lagrangian approach to incompressible fluids that is convenient
for both analysis and physics is presented. Bounds on burning rates in
combustion and heat transfer in convection are discussed, as well as results
concerning spectra.

</DOC>
<DOC>
<DOCNO> 152054 </DOCNO>
Relic gravitons from non-singular string cosmologies


  In the context of the pre-Big Bang scenario of string cosmology, we propose a
modified equation for the evolution of the tensor perturbations, which includes
the full contribution of possible higher-order curvature and coupling
corrections required to regularise the background evolution. We then discuss
the high-frequency branch of the spectrum of primordial gravitons.

</DOC>
<DOC>
<DOCNO> 71122 </DOCNO>
Strongly Distorted Baryon Wave-Functions: Hyperon Beta-Decay and the


  Within the collective coordinate approach to chiral soliton models we suggest
that breaking of SU(3) flavor symmetry mainly resides in the baryon
wave-functions while the charge operators have no (or only small) symmetry
breaking components. In this framework we study the $g_A/g_V$ ratios for
hyperon beta-decay as well as the various quark flavor components of the axial
charge of the nucleon and the $\Lambda$-hyperon.

</DOC>
<DOC>
<DOCNO> 118984 </DOCNO>
Planetary Transits Toward the Galactic Bulge


  The primary difficulty with using transits to discover extrasolar planets is
the low probability a planet has of transiting its parent star. One way of
overcoming this difficulty is to search for transits in dense stellar fields,
such as the Galactic bulge. Here I estimate the number of planets that might be
detected from a monitoring campaign toward the bulge. A campaign lasting 10
nights on a 10 meter telescope (assuming 8 hours of observations per night and
a 5'x5' field of view) would detect about 100 planets with radius $\rp=1.5
\rjup$, or about 30 planets with $\rp=1.0 \rjup$, if the frequency and
distribution of planets in the bulge is similar to that in the solar
neighborhood. Most of these planets will be discovered around stars just below
the turn-off, i.e. slightly evolved G-dwarfs. Campaigns involving 1- or 4-m
class telescopes are unlikely to discover any planets, unless there exists a
substantial population of companions with $\rp > 1.5 \rjup$.

</DOC>
<DOC>
<DOCNO> 83054 </DOCNO>
Minimum Description Length and Compositionality


  We present a non-vacuous definition of compositionality. It is based on the
idea of combining the minimum description length principle with the original
definition of compositionality (that is, that the meaning of the whole is a
function of the meaning of the parts).
  The new definition is intuitive and allows us to distinguish between
compositional and non-compositional semantics, and between idiomatic and
non-idiomatic expressions. It is not ad hoc, since it does not make any
references to non-intrinsic properties of meaning functions (like being a
polynomial). Moreover, it allows us to compare different meaning functions with
respect to how compositional they are. It bridges linguistic and corpus-based,
statistical approaches to natural language understanding.

</DOC>
<DOC>
<DOCNO> 101067 </DOCNO>
On gauge invariant regularization of fermion currents


  We compare Schwinger and complex powers methods to construct regularized
fermion currents. We show that although both of them are gauge invariant they
not always yield the same result.

</DOC>
<DOC>
<DOCNO> 68917 </DOCNO>
Charm Production by Cosmic Muons


  Narrow muon bundles in underground detectors permit to study muoproduction
reactions that take place in the surrounding rock. We analyze the relevance of
a QED+QCD reaction, muoproduction of "open charm". The contribution to double
muon events is estimated to be 4-8 % of the one due to QED "trident" process,
for an ideal detector located under a rock depth of 3 km water equivalent, and
an observation threshold of 1 GeV.

</DOC>
<DOC>
<DOCNO> 118815 </DOCNO>
Quintessence as Unrecaptured Matter from a Universe Bounce


  Since the universe is accelerating due to a negative vacuum energy, there is
great difficulty fitting this into an inflation picture. Using a 160 MeV bounce
model, the negative energy can be due to matter remaining outside the universe.
For a bounce, collapse to infinite density states must be prevented by energy
losses at supranuclear densities. Most other big bang problems are solvable
with this model.

</DOC>
<DOC>
<DOCNO> 67953 </DOCNO>
Measurement of mechanical vibrations excited in aluminium resonators by


  We present measurements of mechanical vibrations induced by 0.6 GeV electrons
impinging on cylindrical and spherical aluminium resonators. To monitor the
amplitude of the resonator's vibrational modes we used piezoelectric ceramic
sensors, calibrated by standard accelerometers. Calculations using the
thermo-acoustic conversion model, agree well with the experimental data, as
demonstrated by the specific variation of the excitation strengths with the
absorbed energy, and with the traversing particles' track positions. For the
first longitudinal mode of the cylindrical resonator we measured a conversion
factor of 7.4 +- 1.4 nm/J, confirming the model value of 10 nm/J. Also, for the
spherical resonator, we found the model values for the L=2 and L=1 mode
amplitudes to be consistent with our measurement. We thus have confirmed the
applicability of the model, and we note that calculations based on the model
have shown that next generation resonant mass gravitational wave detectors can
only be expected to reach their intended ultra high sensitivity if they will be
shielded by an appreciable amount of rock, where a veto detector can reduce the
background of remaining impinging cosmic rays effectively.

</DOC>
<DOC>
<DOCNO> 122170 </DOCNO>
Thermal Comptonization in GRS 1915+105


  The Rossi X-ray Timing Explorer data of GRS 1915+105 from several observing
periods are modeled with a thermal Comptonization model. Best-fit models
indicate that there is a strong correlation between the inner disk temperature
and the disk luminosity. The hard Comptonized luminosity does not depend
significantly on the total luminosity. The spectral hardness of the Comptonized
radiation, the fraction of seed soft photons scattered by the Comptonizing
cloud, its Thomson optical depth, and the fraction of the total power
dissipated in the optically thin hot plasma, all strongly anticorrelate with
the luminosity. We find that the inner disk radius is almost constant and that
the hot Comptonizing corona shrinks at high luminosities. We note that the fits
using xspec diskbb + power law model underestimate the amplitude of the
blackbody component (and therefore the corresponding size of the emitting
region) and overestimate the absorption column density and the total, corrected
for absorption, luminosity.

</DOC>
<DOC>
<DOCNO> 13519 </DOCNO>
Theory of Adsorption on Metal Substrates


  Contents:
 5.1 Introduction
 5.2 Concepts and definitions
 5.3 The tight-binding picture of bonding
 5.4 Adsorption of isolated adatoms
 5.5 Alkali-metal adsorption: the traditional picture of on-surface adsorption
 5.6 Substitutional adsorption and formation of surface alloys
 5.7 Adsorption of CO on transition-metal surfaces - a model system for a
simple molecular adsorbate
 5.8 Co-adsorption [the example CO plus O on Ru(0001)]
 5.9 Chemical reactions at metal surfaces
 5.10 The catalytic oxidation of CO
 5.11 Summary outline of main points

</DOC>
<DOC>
<DOCNO> 68273 </DOCNO>
Estimating eps'/eps in the standard model independently of Im \lambda_t


  The CP-violating parameter eps'/eps is estimated in a novel way by including
the explicit computation of eps in the ratio as opposed to the usual procedure
of taking its value from the experiments. This approach has the advantage of
being independent from the determination of the CKM parameters Im \lambda_t and
of showing more directly the dependence on the long-distance parameters. The
matrix elements are taken from the chiral quark model approach, the parameters
of which have been recently determined by an updated fit of the CP-conserving
amplitudes entering the \Delta I=1/2 rule. By taking a normal distribution for
the experimental inputs and a flat one for the theoretical uncertainties, it is
found that eps '/eps = (2.5 \pm 0.9) \times 10^{-3} in agreement with the
current experimental data. A more conservative estimate 0.9 x 10^{-3} <
eps'/eps < 5.8 x 10^{-3} is found by considering the smallest and the largest
values obtained by taking a flat distribution for all inputs.

</DOC>
<DOC>
<DOCNO> 102002 </DOCNO>
G Add-On, Digital, Sieve, General Periodical, and Non-Arithmetic


  In this paper a small survey is presented on fourteen sequences, such as: G
Add-on Sequences, Sieve Sequences, Digital Sequences, Non-Arithmetic
Progressions, recreational sequences (Lucky
Method/Operation/Algorithm/Differentiation/Integration etc.), General
Periodical Sequences, and numerical functions.

</DOC>
<DOC>
<DOCNO> 123336 </DOCNO>
Neutron stars and strong-field effects of general relativity


  The basic observed properties of neutron stars are reviewed. I suggest that
neutron stars in low-mass X-ray binaries are the best of all known sites for
testing strong-field effects of general relativity.

</DOC>
<DOC>
<DOCNO> 117770 </DOCNO>
The Role of Electron Captures in Chandrasekhar Mass Models for Type Ia


  The Chandrasekhar mass model for Type Ia Supernovae (SNe Ia) has received
increasing support from recent comparisons of observations with light curve
predictions and modeling of synthetic spectra. It explains SN Ia events via
thermonuclear explosions of accreting white dwarfs in binary stellar systems,
being caused by central carbon ignition when the white dwarf approaches the
Chandrasekhar mass. As the electron gas in white dwarfs is degenerate,
characterized by high Fermi energies for the high density regions in the
center, electron capture on intermediate mass and Fe-group nuclei plays an
important role in explosive burning. Electron capture affects the central
electron fraction Y_e, which determines the composition of the ejecta from such
explosions. Up to the present, astrophysical tabulations based on shell model
matrix elements were only available for light nuclei in the sd-shell. Recently
new Shell Model Monte Carlo (SMMC) and large-scale shell model diagonalization
calculations have also been performed for pf-shell nuclei. These lead in
general to a reduction of electron capture rates in comparison with previous,
more phenomenological, approaches. Making use of these new shell model based
rates, we present the first results for the composition of Fe-group nuclei
produced in the central regions of SNe Ia and possible changes in the
constraints on model parameters like ignition densities and burning front
speeds.

</DOC>
<DOC>
<DOCNO> 70220 </DOCNO>
CP violation in gauge theories


  We define the CP transformation properties of scalars, fermions and vectors
in a gauge theory and show that only three types of interactions can lead to CP
violation: scalar interactions, fermion-scalar interactions and $ F \tilde F $
associated with the strong CP problem and which involve only the gauge fields.
For technicolor theories this implies the absence of CP violation within
perturbation theory.

</DOC>
<DOC>
<DOCNO> 120690 </DOCNO>
Large scale jets in AGN: multiwavelength mapping


  X-ray emission from large scale extragalactic jets is likely to be due to
inverse Compton scattering of relativistic particles off seed photons of both
the cosmic microwave background field and the blazar nucleus. The first process
dominates the observed high energy emission of large scale jets if the plasma
is moving at highly relativistic speeds and if the jet is aligned with the line
of sight, i.e. in powerful flat radio spectrum quasars. The second process is
relevant when the plasma is moving at mildly bulk relativistic speeds, and can
dominate the high energy emission in misaligned sources, i.e. in
radio-galaxies. We show that this scenario satisfactorily accounts for the
spectral energy distribution detected by Chandra from the jet and core of PKS
0637-752.

</DOC>
<DOC>
<DOCNO> 10037 </DOCNO>
Quantum phase transition in a random-tiling model


  The analogue of a Mott-Hubbard transition is discussed, which appears at an
incommensurate filling in a model of a two-dimensional plane, randomly tiled
with CuO_4 `molecules', simulating the copper-oxide planes of high-T_c
superconductors. It is shown to be a quantum phase transition, which can be
crossed either in doping, at a fixed hopping overlap t, or in t, when the
doping is fixed in a certain range below half-filling. It is first-order,
closely analogous to a liquid-gas transition.

</DOC>
<DOC>
<DOCNO> 100693 </DOCNO>
Equivalence of Projections as Gauge Equivalence on Noncommutative Space


  Projections play crucial roles in the ADHM construction on noncommutative
$\R^4$. In this article a framework for the description of equivalence
relations between projections is proposed. We treat the equivalence of
projections as ``gauge equivalence'' on noncommutative space. We find an
interesting application of this framework to the study of U(2) instanton on
noncommutative $\R^4$: A zero winding number configuration with a hole at the
origin is ``gauge equivalent'' to the noncommutative analog of the BPST
instanton. Thus the ``gauge transformation'' in this case can be understood as
a noncommutative resolution of the singular gauge transformation in ordinary
$\R^4$.

</DOC>
<DOC>
<DOCNO> 10977 </DOCNO>
Spin Models on Non-Euclidean Hyperlattices: Griffiths Phases without


  We study short-range ferromagnetic models residing on planar manifolds with
global negative curvature. We show that the local metric properties of the
embedding surface induce droplet formation from the boundary, resulting in the
stability of a Griffiths phase at a temperature lower than that of the bulk
transition. We propose that this behavior is independent of order parameter and
hyperlattice specifics, and thus is universal for such non-Euclidean spin
models. Their temperature-curvature phase diagrams are characterized by two
distinct bulk and boundary transitions; each has mean-field critical behavior
and a finite correlation length related to the curvature of the embedding
surface. The implications for experiments on superconducting hyperlattice
networks are also discussed.

</DOC>
<DOC>
<DOCNO> 72183 </DOCNO>
Renormalization Group and Dynamics of Supersymmetric Gauge Theories


  We discuss questions related to renormalization group and to nonperturbative
aspects of non-Abelian gauge theories with N=2 and/or N=1 supersymmetry.
Results on perturbative and nonperturbative $\beta$ functions of these theories
are reviewed, and new mechanisms of confinement and dynamical symmetry breaking
recently found in a class of $SU(n_c)$, $USp(2n_c)$ and $SO(n_c)$ theories are
discussed.

</DOC>
<DOC>
<DOCNO> 100161 </DOCNO>
Schur's old determinant proves a brand-new theorem of


  Garrett, Ismail, and Stanton gave a general formula that contains the
Rogers-Ramanjuan identities as special cases. We show how easy this is when
using a determinant that Schur introduced in 1917.

</DOC>
<DOC>
<DOCNO> 85387 </DOCNO>
Duality and Decoherence Free Subspaces


  Quantum error avoiding codes are constructed by exploiting a geometric
interpretation of the algebra of measurements of an open quantum system. The
notion of a generalized Dirac operator is introduced and used to naturally
construct families of decoherence free subspaces for the encoding of quantum
information. The members of the family are connected to each other by the
discrete Morita equivalences of the algebra of observables, which render
possible several choices of noiseless code in which to perform quantum
computation. The construction is applied to various examples of discrete and
continuous quantum systems.

</DOC>
<DOC>
<DOCNO> 69005 </DOCNO>
Relaxation of the Dynamical Gluino Phase and Unambiguous Electric Dipole


  We propose a new axionic solution of the strong CP problem with a
Peccei-Quinn mechanism using the gluino rather than quarks. The spontaneous
breaking of this new global U(1) at 10^{11} GeV also generates the
supersymmetry breaking scale of 1 TeV (solving the so-called \mu problem at the
same time) and results in the MSSM (Minimal Supersymmetric Standard Model) with
R parity conservation. In this framework, electric dipole moments become
calculable without ambiguity.

</DOC>
<DOC>
<DOCNO> 101111 </DOCNO>
The Scalar-flat Kaehler Metric and Painleve III


  We study the anti-self-dual equation for non-diagonal SU(2)-invariant metrics
and give an equivalent ninth-order system. This system reduce to a sixth-order
system if the metric is in the conformal class of scalar-flat-Kaehler metric.

</DOC>
<DOC>
<DOCNO> 178770 </DOCNO>
Coulomb exchange and pairing contributions in nuclear


  We present exact Hartree-Fock-Bogoliubov calculations with the finite range
density dependent Gogny force using a triaxial basis. For the first time, all
contributions to the Pairing and Fock Fields arising from the Gogny and Coulomb
interactions as well as the two-body correction of the kinetic energy have been
calculated in this basis. We analyze the relevance of these terms in different
regions of the periodic table at zero and high angular momentum. The validity
of commonly used approximations that neglect different terms in the variational
equations is also checked. We find a decrease of the proton pairing energies
mainly due to a Coulomb antipairing effect.

</DOC>
<DOC>
<DOCNO> 70909 </DOCNO>
Implications for quintessence models from MAXIMA-1 and BOOMERANG-98


  Prompted by the recent MAXIMA-1 and BOOMERANG-98 measurements of the cosmic
microwave background (CMB) anisotropy power spectrum, and motivated by the
results from the observation of high-redshift Type Ia supernovae, we
investigate CMB anisotropies in quintessence models in order to characterize
the nature of the dark energy today. We perform a Bayesian likelihood analysis,
using the MAXIMA-1 and BOOMERANG-98 published bandpowers, in combination with
COBE/DMR, to explore the space of quintessence parameters: the quintessence
energy density \Omega_\phi and equation of state w_\phi. We restrict our
analysis to flat, scale-invariant, inflationary adiabatic models. We find that
this simple class of inflationary models, with a quintessence component
\Omega_\phi < ~0.7, -1 < = w_\phi < ~-0.5, is in good agreement with the data.
Within the assumptions of our analysis, pure quintessence models seem to be
slightly favored, although the simple cosmological constant scenario is
consistent with the data.

</DOC>
<DOC>
<DOCNO> 121423 </DOCNO>
Two classes of radio flares in the blazar PKS 0420$-$014


  The two 5GHz VLBI (Very Long Baseline Interferometry) observations (1996 June
and 1997 November) presented in this paper, combined with several formerb VLBI
observations at 8.4GHz and 5GHz, suggest that the radio flares of the blazar
PKS 0420$-$014 can be divided into two classes according to their geometric
origins in 5 or 8.4GHz VLBI maps and the properties of light curves. One class
of flares, which we call {\it core flares}, originate from the core. Core
flares have large lags between the light curves at different frequencies, and
will probably lead to the ejection of new jet components. The other class of
flares, which we call {\it jet flares}, come from jet components. Jet flares
vary simultaneously at different wavelengths, and may due to the Doppler
boosting effect of rotating knots moving along a helical jet. The radio flare
in 1991, accompanied by a simultaneous gamma-ray flare, was identified as a
core flare.

</DOC>
<DOC>
<DOCNO> 70795 </DOCNO>
Neutrino interactions with a weak slowly varying electromagnetic field


  We derive the effective action for processes involving two neutrinos and two
photons at energies much below the electron mass. We discuss several
applications in which one or both photons are replaced by external fields. In
particular, Cherenkov radiation and neutrino pair production in weak external
fields are investigated for massive Dirac neutrinos.

</DOC>
<DOC>
<DOCNO> 83499 </DOCNO>
Towards a Universal Theory of Artificial Intelligence based on


  Decision theory formally solves the problem of rational agents in uncertain
worlds if the true environmental probability distribution is known.
Solomonoff's theory of universal induction formally solves the problem of
sequence prediction for unknown distribution. We unify both theories and give
strong arguments that the resulting universal AIXI model behaves optimal in any
computable environment. The major drawback of the AIXI model is that it is
uncomputable. To overcome this problem, we construct a modified algorithm
AIXI^tl, which is still superior to any other time t and space l bounded agent.
The computation time of AIXI^tl is of the order t x 2^l.

</DOC>
<DOC>
<DOCNO> 117067 </DOCNO>
Slice Sampling


  Markov chain sampling methods that automatically adapt to characteristics of
the distribution being sampled can be constructed by exploiting the principle
that one can sample from a distribution by sampling uniformly from the region
under the plot of its density function. A Markov chain that converges to this
uniform distribution can be constructed by alternating uniform sampling in the
vertical direction with uniform sampling from the horizontal `slice' defined by
the current vertical position, or more generally, with some update that leaves
the uniform distribution over this slice invariant. Variations on such `slice
sampling' methods are easily implemented for univariate distributions, and can
be used to sample from a multivariate distribution by updating each variable in
turn. This approach is often easier to implement than Gibbs sampling, and more
efficient than simple Metropolis updates, due to the ability of slice sampling
to adaptively choose the magnitude of changes made. It is therefore attractive
for routine and automated use. Slice sampling methods that update all variables
simultaneously are also possible. These methods can adaptively choose the
magnitudes of changes made to each variable, based on the local properties of
the density function. More ambitiously, such methods could potentially allow
the sampling to adapt to dependencies between variables by constructing local
quadratic approximations. Another approach is to improve sampling efficiency by
suppressing random walks. This can be done using `overrelaxed' versions of
univariate slice sampling procedures, or by using `reflective' multivariate
slice sampling methods, which bounce off the edges of the slice.

</DOC>
<DOC>
<DOCNO> 68967 </DOCNO>
Magnetic Catalysis in the Presence of Scalar Fields


  The influence of scalar field interactions in the magnetic catalysis
phenomenom is studied in a gauge theory with scalar and fermion fields. It is
shown that the external magnetic field catalyzes the appearance of a
fermion-antifermion condensate along with a non-zero scalar vev, hence
generating a fermion dynamical mass and breaking the discrete chiral symmetry
of the theory. The model does not require the introduction of a scalar mass
term with a wrong sign in the original Lagrangian to generate the scalar vev,
nor does it exhibit dimensional transmutation ''a la Coleman-Weinberg.'' The
scalar vev noticeably enhances the dynamically generated fermion mass. Possible
cosmological applications of these results are suggested.

</DOC>
<DOC>
<DOCNO> 118922 </DOCNO>
The Orbit of X Per and Its Neutron Star Companion


  We have observed the Be/X-ray pulsar binary system X Per/4U 0352+30 on 61
occasions spanning an interval of 600 days with the PCA instrument on RXTE.
Pulse timing analyses of the 837-s pulsations yield strong evidence for the
presence of orbital Doppler delays. We confirm the Doppler delays by using
measurements made with the RXTE All-Sky Monitor. We obtain an orbital period of
250 days, a projected semimajor axis of the neutron star of 454 lt-s, a mass
function of 1.61 solar masses, and a modest eccentricity of 0.11. We discuss
the formation of the system in the context of the standard evolutionary
scenario for Be/X-ray binaries with consideration of the possibility that the
birth of the neutron star was accompanied by a kick of the type often inferred
from the velocity distribution of isolated radio pulsars. The orbital
eccentricity just after the supernova explosion was almost certainly virtually
the same as at present, because the Be star is much smaller than the orbital
separation. We find that the system most likely formed from a pair of massive
progenitor stars, and probably involved a quasi-stable and nearly conservative
transfer of mass from the primary to the secondary. We find that the He star
remnant of the primary most likely had a mass less than 6 solar masses after
mass transfer. Finally, we speculate that there may be a substantial population
of neutron stars formed with little or no kick.

</DOC>
<DOC>
<DOCNO> 80621 </DOCNO>
Isocliny in spinor space and Wilson fermions


  We show that Clifford algebras are closely related to the study of isoclinic
subspaces of spinor spaces and, consequently, to the Hurwitz-Radon matrix
problem. Isocliny angles are introduced to parametrize gamma matrices, i.e.,
matrix representations of the generators of finite-dimensional Clifford
algebras C(m,n). Restricting the consideration to the Clifford algebra C(4,0),
this parametrization is then applied to the study of Dirac traces occurring in
Euclidean lattice quantum field theory within the hopping parameter expansion
for Wilson fermions.

</DOC>
<DOC>
<DOCNO> 150321 </DOCNO>
Poisson-Sigma Models


  We investigate the Poisson-Sigma model on the classical and quantum level. In
the classical analysis we show how this model includes various known
two-dimensional field theories. Then we perform the calculation of the path
integral in a general gauge, and demonstrate that the derived partition
function reduces to the familiar form in the case of 2d Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 67925 </DOCNO>
Generation of large flavor mixing from radiative corrections


  We provide a model independent criterion which would guarantee a large flavor
mixing of two quasi-degenerate Majorana neutrinos at the low scale,
irrespective of the mixing at the high scale. We also show that such a
situation is realizable for a phenomenologically interesting range of
parameters of the weak scale theory. We further show that for a similar
condition to be implementable for the three generation case, the CP parity of
one of the neutrinos needs to be opposite to that of the others.

</DOC>
<DOC>
<DOCNO> 10000 </DOCNO>
Reply to Comment on ``Thermal Model for Adaptive Competition in a


  We reply to the Comment of Challet et al. [cond-mat/0004308] on our paper
[Phys. Rev. Lett. 83, 4429 (1999)]. We show that the claim of the Comment that
the effects of the temperature in the Thermal Minority Game ``can be eliminated
by time rescaling'' and consequently the behaviour is ``independent of T'' has
no general validity.

</DOC>
<DOC>
<DOCNO> 100879 </DOCNO>
Wedge extendability of CR-meromorphic functions: the minimal case


  Let M be a C^{4,a}-smooth (a>0) generic manifold in C^{m+n} of CR dimension
m>0 and codimension n>0 which is minimal at every point. Then there exists a
wedge W attached to M to which all CR-meromorphic functions extend
meromorphically.

</DOC>
<DOC>
<DOCNO> 85152 </DOCNO>
Models of Universe with a Delayed Big-Bang singularity. III. Solving the


  This paper is the third of a series dedicated to the study of the Delayed
Big-Bang (DBB) class of inhomogeneous cosmological models of
Lema\^itre-Tolman-Bondi type. In the first work, it was shown that the
geometrical properties of the DBB model are such that the horizon problem can
be solved, without need for any inflationary phase, for an observer situated
sufficiently near the symmetry center of the model to justify the ``centered
earth'' approximation. In the second work, we studied, in a peculiar subclass
of the DBB models, the extent to which the values of the dipole and quadrupole
moments measured in the cosmic microwave background radiation (CMBR)
temperature anisotropies can support a cosmological origin. This implies a
relation between the location of the observer in the universe and the model
parameter value: the farther the observer from the symmetry center, the closer
our current universe to a local homogeneous pattern. However, in this case, the
centered earth approximation is no longer valid and the results of the first
work do not apply. We show here that the horizon problem can be solved, in the
DBB model, also for an off-center observer, which improves the consistency of
this model regarding the assumption of a CMBR large scale anisotropy
cosmological origin.

</DOC>
<DOC>
<DOCNO> 8474 </DOCNO>
Sum Rule Approach to Collective Oscillations of Boson-Fermion Mixed


  The behavior of collective oscillations of a trapped boson-fermion mixed
condensate is studied in the sum rule approach. Mixing angle of bosonic and
fermionic multipole operators is introduced so that the mixing characters of
the low-lying collective modes are studied as functions of the boson-fermion
interaction strength. For an attractive boson-fermion interaction, the
low-lying monopole mode becomes a coherent oscillation of bosons and fermions
and shows a rapid decrease in the excitation energy towards the instability
point of the ground state. In contrast, the low-lying quadrupole mode keeps a
bosonic character over a wide range of the interaction strengths. For the
dipole mode the boson-fermion in-phase oscillation remains to be the eigenmode
under the external oscillator potential. For weak repulsive values of the
boson-fermion interaction strengths we found that an average energy of the
out-of-phase dipole mode stays lower than the in-phase oscillation.
 Physical origin of the behavior of the multipole modes against boson-fermion
interaction strength is discussed in some detail.

</DOC>
<DOC>
<DOCNO> 10937 </DOCNO>
A Quantum Fluctuation Theorem


  We consider a quantum system strongly driven by forces that are periodic in
time. The theorem concerns the probability $P(e)$ of observing a given energy
change $e$ after a number of cycles. If the system is thermostated by a
(quantum) thermal bath, $e$ is the total amount of energy transferred to the
bath, while for an isolated system
 $e$ is the increase in energy of the system itself. Then, we show that
$P(e)/P(-e)=e^{\beta e}$, a parameter-free, model-independent relation.

</DOC>
<DOC>
<DOCNO> 116483 </DOCNO>
Fast Algorithm for Finding the Eigenvalue Distribution of Very Large


  A theoretical analysis is given of the equation of motion method, due to
Alben et al., to compute the eigenvalue distribution (density of states) of
very large matrices. The salient feature of this method is that for matrices of
the kind encountered in quantum physics the memory and CPU requirements of this
method scale linearly with the dimension of the matrix. We derive a rigorous
estimate of the statistical error, supporting earlier observations that the
computational efficiency of this approach increases with matrix size. We use
this method and an imaginary-time version of it to compute the energy and the
specific heat of three different, exactly solvable, spin-1/2 models and compare
with the exact results to study the dependence of the statistical errors on
sample and matrix size.

</DOC>
<DOC>
<DOCNO> 83512 </DOCNO>
Byzantine Agreement with Bounded Broadcast


  Byzantine Agreement introduced in [Pease, Shostak, Lamport, 80] is a widely
used building block of reliable distributed protocols. It simulates broadcast
despite the presence of faulty parties within the network, traditionally using
only private unicast links. Under such conditions, Byzantine Agreement requires
more than 2/3 of the parties to be honest. [Fitzi, Maurer, 00], constructed a
Byzantine Agreement protocol for any honest majority based on an additional
primitive allowing transmission to any two parties simultaneously. We
generalize these results using a primitive allowing transmission among any
fixed number of parties simultaneously, and prove that a 2k party channel is
necessary and sufficient for implementing broadcast when honest parties are in
1/k minority.

</DOC>
<DOC>
<DOCNO> 70992 </DOCNO>
Testing the Leutwyler-Smilga prediction regarding the global topological


  I give a sketch of my recent attempt to test the prediction by Leutwyler and
Smilga according to which, for QCD in a finite box with $N_{f} \geq 2$, the
combination $x = V \Sigma m$ indicates whether the net topological charge of
the gauge background proves relevant ($x \ll 1$) or irrelevant ($x \gg 1$) for
physical observables.

</DOC>
<DOC>
<DOCNO> 80999 </DOCNO>
Parallel Computing for QCD on a Pentium Cluster


  Motivated by the computational demands of our research and budgetary
constraints which are common to many research institutions, we built a ``poor
man's supercomputer'', a cluster of PC nodes which together can perform
parallel calculations at a fraction of the price of a commercial supercomputer.
We describe the construction, cost, and performance of our cluster.

</DOC>
<DOC>
<DOCNO> 151752 </DOCNO>
Discrete Torsion


  In this article we explain discrete torsion. Put simply, discrete torsion is
the choice of orbifold group action on the B field. We derive the
classification H^2(G, U(1)), we derive the twisted sector phases appearing in
string loop partition functions, we derive M. Douglas's description of discrete
torsion for D-branes in terms of a projective representation of the orbifold
group, and we outline how the results of Vafa-Witten fit into this framework.
In addition, we discover some new degrees of freedom that appear in describing
orbifold group actions on B fields, in addition to those classified by H^2(G,
U(1)), and explain how these new degrees of freedom appear in terms of twisted
sector contributions to partition functions and in terms of orbifold group
actions on D-brane worldvolumes. This paper represents a technically simplified
version of prior papers by the author on discrete torsion. We repeat here
technically simplified versions of results from those papers, and have included
some new material.

</DOC>
<DOC>
<DOCNO> 150490 </DOCNO>
Superspace Geometrical Realization of the N-Extended Super Virasoro


  We derive properties of N-extended GR super Virasoro algebras. These include
adding central extensions, identification of all primary fields and the action
of the adjoint representation on its dual. The final result suggest
identification with the spectrum of fields in supergravity theories and
superstring/M-theory constructed from NSR N-extended supersymmetric ${\cal
{GR}}$ Virasoro algebras.

</DOC>
<DOC>
<DOCNO> 119378 </DOCNO>
Evidence consistent with the cosmological interpretation of quasar


  In this letter, the old issue of whether redshifts of quasars are of
cosmological origin is investigated. We make a plot of absorption redshifts
versus emission redshifts for quasars with large amounts of data. Our study
shows that, almost all absorption redshifts are smaller than the corresponding
emission redshifts. The relation between the absorption and emission redshifts
predicted by current cosmological models is well obeyed. The result confirms
that redshifts of quasars are indeed distance indicators. It might be the most
obvious evidence found so far to be consistent with the cosmological
interpretation of quasar redshifts.

</DOC>
<DOC>
<DOCNO> 13165 </DOCNO>
Insulator-to-metal crossover induced by local spin fluctuations in


  We study the simplified Hubbard (SH) model in the presence of a transverse
field in the infinite dimension limit. The relevant one-particle Green's
functions of the model are obtained by means a perturbative treatment of the
hopping and of the transverse field around the atomic limit. We consider an
analytical solution for the impurity problem. It is shown that this solution is
very accurate in describing the spectral properties of the heavy-particles of
the SH for intermediate and strong values of the on-site Coulomb interaction
$U$. We find that for large values of $U$ an insulator-metal transition takes
place as a function of the transverse field. We analyze the metallic phase
through the behavior of the density of states and of the optical conductivity
and static resistivity. Our results for the latter quantity agree with what is
observed in experiments on $Bi_2Sr_2CuO_y$.

</DOC>
<DOC>
<DOCNO> 118752 </DOCNO>
Magellanic Cloud Periphery Carbon Stars IV: The SMC


  The kinematics of 150 carbon stars observed at moderate dispersion on the
periphery of the Small Magellanic Cloud are compared with the motions of
neutral hydrogen and early type stars in the Inter-Cloud region. The
distribution of radial velocities implies a configuration of these stars as a
sheet inclined at 73+/-4 degrees to the plane of the sky. The near side, to the
South, is dominated by a stellar component; to the North, the far side contains
fewer carbon stars, and is dominated by the neutral gas. The upper velocity
envelope of the stars is closely the same as that of the gas. This
configuration is shown to be consistent with the known extension of the SMC
along the line of sight, and is attributed to a tidally induced disruption of
the SMC that originated in a close encounter with the LMC some 0.3 to 0.4 Gyr
ago. The dearth of gas on the near side of the sheet is attributed to ablation
processes akin to those inferred by Weiner & Williams (1996) to collisional
excitation of the leading edges of Magellanic Stream clouds. Comparison with
pre LMC/SMC encounter kinematic data of Hardy, Suntzeff, & Azzopardi (1989) of
carbon stars, with data of stars formed after the encounter, of Maurice et al.
(1989), and Mathewson et al. (a986, 1988) leaves little doubt that forces other
than gravity play a role in the dynamics of the H I.

</DOC>
<DOC>
<DOCNO> 12136 </DOCNO>
Transport properties of quantum dots with hard walls


  Quantum dots are fabricated in a Ga[Al]As-heterostructure by local oxidation
with an atomic force microscope. This technique, in combination with top gate
voltages, allows us to generate steep walls at the confining edges and small
lateral depletion lengths. The confinement is characterized by low-temperature
magnetotransport measurements, from which the dots' energy spectrum is
reconstructed. We find that in small dots, the addition spectrum can
qualitatively be described within a Fock-Darwin model. For a quantitative
analysis, however, a hard-wall confinement has to be considered. In large dots,
the energy level spectrum deviates even qualitatively from a Fock-Darwin model.
The maximum wall steepness achieved is of the order of 0.4 meV/nm.

</DOC>
<DOC>
<DOCNO> 121615 </DOCNO>
Probing Early Structure Formation with Far-Infrared Background


  The large-scale structure of high-redshift galaxies produces correlated
anisotropy in the far-infrared background (FIRB). In regions of the sky where
the thermal emission from Galactic dust is well below average, these
high-redshift correlations may be the most significant source of angular
fluctuation power over a wide range of angular scales, from about 7' to about 3
degrees, and frequencies, from about 400 to about 1000 GHz. The strength of
this signal should allow detailed studies of the statistics of the FIRB
fluctuations, including the shape of the angular power spectrum at a given
frequency and the degree of coherence between FIRB maps at different
frequencies. The FIRB correlations depend upon and hence constrain the
redshift-dependent spectral energy distributions, number counts, and clustering
bias of the galaxies and active nuclei that contribute to the background. We
quantify the accuracy to which Planck and a newly proposed balloon-borne
mission EDGE could constrain models of the high-redshift universe through the
measurement of FIRB fluctuations. We conclude that the average bias of
high-redshift galaxies could be measured to an accuracy of less than
approximately 1% or, for example, separated into 4 redshift bins with about 10%
accuracy.

</DOC>
<DOC>
<DOCNO> 152289 </DOCNO>
Wound String Scattering in NCOS Theory


  We calculate the amplitude for a non-excited closed string with nonzero
winding number to scatter from a D-string with a near critical E field. We go
to the NCOS limit and observe that we get the same result if we adopt another
approach put forward by Gomis and Ooguri.

</DOC>
<DOC>
<DOCNO> 71439 </DOCNO>
Can the SO(10) Model with Two Higgs Doublets Reproduce the Observed


  It is usually considered that the SO(10) model with one 10 and one 126 Higgs
scalars cannot reproduce the observed quark and charged lepton masses. Against
this conventional conjecture, we find solutions of the parameters which can
give the observed fermion mass spectra. The SO(10) model with one 10 and one
120 Higgs scalars is also discussed.

</DOC>
<DOC>
<DOCNO> 39849 </DOCNO>
Neutrino oscillation experiments and limits on lepton-number and


  Using a three neutrino framework we investigate bounds for the effective
Majorana neutrino mass matrix. The mass measured in neutrinoless double beta
decay is its (11) element. Lepton-number and -flavor violating processes
sensitive to each element are considered and limits on branching ratios or
cross sections are given. Those processes include $\mu^- e^+$ conversion, $K^+
\to \pi^- \mu^+ \mu^+$ or recently proposed high-energy scattering processes at
HERA. Including all possible mass schemes, the three solar solutions and other
allowed possibilities, there is a total of 80 mass matrices. The obtained
indirect limits are up to 14 orders of magnitude more stringent than direct
ones. It is investigated how neutrinoless double beta decay may judge between
different mass and mixing schemes as well as solar solutions. Prospects for
detecting processes depending on elements of the mass matrix are also
discussed.

</DOC>
<DOC>
<DOCNO> 123173 </DOCNO>
VLA and MERLIN monitoring observations of the gravitational lens system


  We present VLA and MERLIN monitoring data of the JVAS gravitational lens
system B1030+074. The system was monitored with the VLA from February 1998 to
October 1998 at 8.4-GHz during which the VLA was at its A, BnA and B
configuration. The 47 epochs of observations have an average spacing of
approximately 5 days. Ten MERLIN snapshots were obtained in the L-band (1.7
GHz) during the months of April, May and June 1998. Preliminary light curves of
the two components of the lens system obtained from the VLA data indicate that
during the period of the monitoring the A flux density showed a steady
decrease. No changes are observed in the B light curve.

</DOC>
<DOC>
<DOCNO> 12313 </DOCNO>
The Broad Brillouin Doublet and CP of Ktao_3 : Second Sound vs.


  Low-T Brillouin spectra of the incipient ferroelectric KTaO3 exhibit a broad
central peak (CP), and additional Brillouin doublets (BD), that can both be
related to phonon-density fluctuations. On the basis of new high-resolution
neutron data obtained of low-lying phonon branches, we analysed the
phonon-kinetics mechanisms that are possibly the origin of these unusual
features. Firstly, transverse acoustic (TA) phonons whose normal damping is
faster than the BD frequency can produce hydrodynamic second sound. Secondly,
two-phonon difference scattering from low damping thermal transverse phonons
contribute to the spectra with either a sharp or a broader doublet, depending
on the phonon group velocity and anisotropy of dispersion surfaces. The
position of the observed sharp doublet is consistent with both mechanisms, but
a comparison of the computed and experimental anisotropies favours the second
process.

</DOC>
<DOC>
<DOCNO> 116860 </DOCNO>
Superconducting H-mode Structures for Medium Energy Beams


  Room temperature IH-type drift tube structures are used at different places
now for the acceleration of ions with mass over charge ratios up to 65 and
velocities between 0.016 c and 0.1 c. These structures have a high shunt
impedance and allow the acceleration of very intense beams at high accelerating
gradients. The overall power consumption of room temperature IH-mode structures
is comparable with superconducting (sc) structures up to 2 MeV/u. With the
KONUS [1] beam dynamics, the required transversal focusing elements, e.g.
quadrupole triplets can be placed outside of multicell cavities, which is
favourable for building sc H-mode cavities. The design principles and
consequences to the geometry compared to room temperature (rt) cavities will be
described. The results gained from numerical simulations show that a sc
multi-gap H21(0)-mode cavity (CH-type) can be an alternative to the sc
spoke-type or reentrant cavity structures up to beam energies around 150 MeV/u.
The main cavity parameters and possible fabrication options will be discussed.
  [1] U. Ratzinger, Nucl. Intr. Meth., A 415 (1998) 229.

</DOC>
<DOC>
<DOCNO> 12616 </DOCNO>
$1/f^\alpha$ noise from self-organized critical models with uniform


  Using the well-known Olami-Feder-Christensen model as our paradigm, we show
how to modify uniform driven self-organized critical models to generate
$1/f^\alpha$ noise. Our model can reproduce all the main features of
$1/f^\alpha$ noise: (1) $\alpha$ is close to one and does not depend on the
dimension of the system. (2) The $1/f^\alpha$ behavior is found for very low
frequencies. (3) The spatial correlations do not obey a power law. That proves
that spatially extended systems based on activation-deactivation processes do
not have to be point-driven to produce $1/f^\alpha$ noise. The essential
ingredient is a local memory of the activation-deactivation process.

</DOC>
<DOC>
<DOCNO> 9133 </DOCNO>
Hall Crystal States at $\nu=2$ and Moderate Landau Level Mixing


  The $\nu=2$ quantum Hall state at low Zeeman coupling is well-known to be a
translationally invariant singlet if Landau level mixing is small. At zero
Zeeman interaction, as Landau level mixing increases, the translationally
invariant state becomes unstable to aninhomogeneous state. This is the first
realistic example of a full Hall crystal, which shows the coexistence of
quantum Hall order and density wave order. The full Hall crystal differs from
the more familiar Wigner crystal by a topological property, which results in it
having only linearly dispersing collective modes at small $q$, and no $q^{3/2}$
magnetophonon. I present calculations of the topological number and the
collective modes.

</DOC>
<DOC>
<DOCNO> 101892 </DOCNO>
Numerical Evidence that the Perturbation Expansion for a Non-Hermitian


  Recently, several studies of non-Hermitian Hamiltonians having $\mathcal{PT}$
symmetry have been conducted. Most striking about these complex Hamiltonians is
how closely their properties resemble those of conventional Hermitian
Hamiltonians. This paper presents further evidence of the similarity of these
Hamiltonians to Hermitian Hamiltonians by examining the summation of the
divergent weak-coupling perturbation series for the ground-state energy of the
$\mathcal{PT}$-symmetric Hamiltonian $H=p^2+{1/4}x^2+i\lambda x^3$ recently
studied by Bender and Dunne. For this purpose the first 193 (nonzero)
coefficients of the Rayleigh-Schr\"odinger perturbation series in powers of
$\lambda^2$ for the ground-state energy were calculated. Pad\'e-summation and
Pad\'e-prediction techniques recently described by Weniger are applied to this
perturbation series. The qualitative features of the results obtained in this
way are indistinguishable from those obtained in the case of the perturbation
series for the quartic anharmonic oscillator, which is known to be a Stieltjes
series.

</DOC>
<DOC>
<DOCNO> 122938 </DOCNO>
Spectra and power of blazar jets


  The spectra of blazars form a sequence which can be parametrized in term of
their observed bolometric luminosity. At the most powerful extreme of the
sequence we find objects whose jet power can rival the power extracted by
accretion, while at the low power end of the sequence we find TeV and TeV
candidate blazars, whose spectral properties can give information on the
particle acceleration mechanism and can help to measure the IR background. Most
of the emission of blazars is produced at a distance of few hundreds
Schwarzschild radii from the center, and must be a small fraction of the
kinetic power carried by the jet itself: most of the jet energy must be
transported outwards, to power the extended radio structures. The radiation
produced by jets can be the result of internal shocks between shells of plasma
with different bulk Lorentz factors. This mechanism, thought to be at the
origin of the gamma-rays observed in gamma-ray bursts, can work even better in
blazars, explaining the observed main characteristics of these objects. Chandra
very recently discovered large scale X-ray jets both in blazars and in
radio-galaxies, which can be explained by enhanced Compton emission with
respect to a pure synchrotron self Compton model. In fact, besides the local
synchrotron emission, the radiation coming from the sub-pc jet core and the
cosmic background radiation can provide seed photons for the scattering
process, enahancing the large scale jet X-ray emission in radio-galaxies and
blazars, respectively.

</DOC>
<DOC>
<DOCNO> 69151 </DOCNO>
Traversing the QCD Phase Transition: Quenching Out of Equilibrium vs.


  I review arguments for the existence of a critical point E in the QCD phase
diagram as a function of temperature T and baryon chemical potential \mu. I
describe how heavy ion collision experiments at the SPS and RHIC can discover
the tell-tale signatures of such a critical point, thus mapping this region of
the QCD phase diagram. I contrast the different ways in which the matter
produced in a heavy ion collision can be driven out of equilibrium: quenching
out of equilibrium (possible, but not guaranteed, if the transition region is
traversed at \mu << \mu_E) vs. slowing out of equilibrium (guaranteed for \mu
\sim \mu_E) vs. bubbling out of equilibrium (possible, but not guaranteed, for
\mu >> \mu_E). Quenching or bubbling create and amplify distinct, detectable,
non-gaussian fluctuations. In contrast, slowing out of equilibrium reduces the
magnitude of the specific, detectable, gaussian fluctuations which signal the
presence of the critical point.

</DOC>
<DOC>
<DOCNO> 72145 </DOCNO>
A criterion for admissible singularities in brane world


  When gravity couples to scalar fields in Anti-de Sitter space, the geometry
becomes non-AdS and develops singularities generally. We propose a criterion
that the singularity is physically admissible if the integral of the on-shell
Lagrangian density over the finite range is finite everywhere. For all classes
of the singularities studied here, the criterion suggested in this paper
coincides with an independent proposal made by Gubser that the potential should
be bounded from above in the solution. This gives a reason why Gubser's
conjecture works.

</DOC>
<DOC>
<DOCNO> 121653 </DOCNO>
Infall models of Class 0 protostars


  We have carried out radiative transfer calculations of infalling, dusty
envelopes surrounding embedded protostars to understand the observed properties
of the recently identified ``Class 0'' sources. To match the far-infrared peaks
in the spectral energy distributions of objects such as the prototype Class 0
source VLA 1623, pure collapse models require mass infall rates
$\sim10^{-4}\msun$yr$^{-1}$. The radial intensity distributions predicted by
such infall models are inconsistent with observations of VLA 1623 at sub-mm
wavelengths, in agreement with the results of Andre et al. (1993) who found a
density profile of $\rho \propto r^{-1/2}$ rather than the expected $\rho
\propto r^{-3/2}$ gradient. To resolve this conflict, while still invoking
infall to produce the outflow source at the center of VLA 1623, we suggest that
the observed sub-mm intensity distribution is the sum of two components: an
inner infall zone, plus an outer, more nearly constant-density region. This
explanation of the observations requires that roughly half the total mass
observed within 2000 AU radius of the source lies in a region external to the
infall zone. The column densities for this external region are comparable to
those found in the larger Oph A cloud within which VLA 1623 is embedded. The
extreme environments of Class 0 sources lead us to suggest an alternative or
additional interpretation of these objects: rather than simply concluding with
Andre et al. that Class 0 objects only represent the earliest phases of
protostellar collapse, and ultimately evolve into older ``Class I'' protostars,
we suggest that many Class 0 sources could be the protostars of very dense
regions. (Shortened)

</DOC>
<DOC>
<DOCNO> 122797 </DOCNO>
The spherical collapse model in a universe with cosmological constant


  We generalize the spherical collapse model for the formation of dark matter
halos to apply in a universe with arbitrary positive cosmological constant. We
calculate the critical condition for collapse of an overdense region and give
exact values of the characteristic densities and redshifts of its evolution.

</DOC>
<DOC>
<DOCNO> 118588 </DOCNO>
A code for optically thick and hot photoionized media


  We describe a code designed for hot media {(T $\ge$} a few 10$^4$ K),
optically thick to Compton scattering. It computes the structure of a
plane-parallel slab of gas in thermal and ionization equilibrium, illuminated
on one or on both sides by a given spectrum. Contrary to the other
photoionization codes, it solves the transfer of the continuum and of the lines
in a two stream approximation, without using the local escape probability
formalism to approximate the line transfer. We stress the importance of taking
into account the returning flux even for small column densities (10$^{22}$
cm$^{-2}$), and we show that the escape probability approximation can lead to
strong errors in the thermal and ionization structure, as well as in the
emitted spectrum, for a Thomson thickness larger than a few tenths. The
transfer code is coupled with a Monte Carlo code which allows to take into
account Compton and inverse Compton diffusions, and to compute the spectrum
emitted up to MeV energies, in any geometry. Comparisons with {\sc{cloudy}}
show that it gives similar results for small column densities. Several
applications are mentioned.

</DOC>
<DOC>
<DOCNO> 39866 </DOCNO>
Mini-review on Collider Signatures for Extra Dimensions


  In this talk, I briefly review collider signatures for two models of extra
dimensions. The first one was proposed by Arkani-Hamed {\it et al.} that
gravity is free to propagate in extra dimensions of very large size ($\alt 1$
mm). Collider signatures for this model can be divided into two types: (i)
emission of real gravitons into extra dimensions, and (ii) exchanges of virtual
gravitons. The second model was proposed by Pomarol {\it et al.} and Dienes
{\it et al.} that the SM gauge bosons are allowed to propagate in extra
dimensions. Collider signatures for the second model are due to the existence
of the Kaluza-Klein (KK) states of $\gamma$, $W$, $Z$, and $g$ bosons.

</DOC>
<DOC>
<DOCNO> 178386 </DOCNO>
Dressing the nucleon in a dispersion approach


  We present a model for dressing the nucleon propagator and vertices. In the
model the use of a K-matrix approach (unitarity) and dispersion relations
(analyticity) are combined. The principal application of the model lies in
pion-nucleon scattering where we discuss effects of the dressing on the phase
shifts.

</DOC>
<DOC>
<DOCNO> 68868 </DOCNO>
Effect of the Charm Quark Mass on the BFKL gamma^* gamma^* Total Cross


  We perform a numerical study of various improvements of the LO BFKL
prediction for the gamma^* gamma^* total cross section in the kinematical
region of the L3 detector at LEP. In particular, we study the effects of a
massive charm quark and of different photon polarizations. The variation of the
BFKL prediction under changes of alpha_s is investigated.

</DOC>
<DOC>
<DOCNO> 83472 </DOCNO>
Logic Programming Approaches for Representing and Solving Constraint


  Many logic programming based approaches can be used to describe and solve
combinatorial search problems. On the one hand there is constraint logic
programming which computes a solution as an answer substitution to a query
containing the variables of the constraint satisfaction problem. On the other
hand there are systems based on stable model semantics, abductive systems, and
first order logic model generators which compute solutions as models of some
theory. This paper compares these different approaches from the point of view
of knowledge representation (how declarative are the programs) and from the
point of view of performance (how good are they at solving typical problems).

</DOC>
<DOC>
<DOCNO> 120992 </DOCNO>
First Results from the Heidelberg Dark Matter Search Experiment


  The Heidelberg Dark Matter Search Experiment (HDMS) is a new ionization
Germanium experiment in a special design. Two concentric Ge crystals are housed
by one cryostat system, the outer detector acting as an effective shield
against multiple scattered photons for the inner crystal, which is the actual
dark matter target. We present first results after successfully running the
prototype detector for a period of about 15 months in the Gran Sasso
Underground Laboratory. We analyze the results in terms of limits on
WIMP-nucleon cross sections and present the status of the full scale
experiment, which will be installed in Gran Sasso in the course of this year.

</DOC>
<DOC>
<DOCNO> 14117 </DOCNO>
Absence of self-averaging in the complex admittance for transport


  A random walk model in a one dimensional disordered medium with an
oscillatory input current is presented as a generic model of boundary
perturbation methods to investigate properties of a transport process in a
disordered medium. It is rigorously shown that an admittance which is equal to
the Fourier-Laplace transform of the first-passage time distribution is
non-self-averaging when the disorder is strong. The low frequency behavior of
the disorder-averaged admittance, $<\chi > -1 \sim \omega^{\mu}$ where $\mu <
1$, does not coincide with the low frequency behavior of the admittance for any
sample, $\chi - 1 \sim \omega$. It implies that the Cole-Cole plot of $<\chi>$
appears at a different position from the Cole-Cole plots of $\chi$ of any
sample. These results are confirmed by Monte-Carlo simulations.

</DOC>
<DOC>
<DOCNO> 117931 </DOCNO>
The first COMPTEL Source Catalogue


  The imaging Compton telescope COMPTEL aboard NASA's Compton Gamma-Ray
Observatory has opened the MeV gamma-ray band as a new window to astronomy.
COMPTEL provided the first complete all-sky survey in the energy range 0.75 to
30 MeV. The catalogue, presented here, is largely restricted to published
results. It contains firm as well as marginal detections of continuum and line
emitting sources and presents upper limits for various types of objects. The
numbers of the most significant detections are 32 for steady sources and 31 for
gamma-ray bursters. Among the continuum sources, detected so far, are spin-down
pulsars, stellar black-hole candidates, supernova remnants, interstellar
clouds, nuclei of active galaxies, gamma-ray bursters, and the Sun during solar
flares. Line detections have been made in the light of the 1.809 MeV 26Al line,
the 1.157 MeV 44Ti line, the 847 and 1238 keV 56Co lines, and the neutron
capture line at 2.223 MeV. For the identification of galactic sources, a
modelling of the diffuse galactic emission is essential. Such a modelling at
this time does not yet exist at the required degree of accuracy. Therefore, a
second COMPTEL source catalogue will be produced after a detailed and accurate
modelling of the diffuse interstellar emission has become possible.

</DOC>
<DOC>
<DOCNO> 9782 </DOCNO>
STM Studies of the Electronic Structure of Vortex Cores in


  We report on low temperature scanning tunneling microscopy (STM) studies of
the electronic structure of vortex cores in Bi2Sr2CaCu2O8+d (BSCCO). At the
vortex core center, an enhanced density-of-states (DOS) is observed at energies
near 7 meV. Spectroscopic imaging at these energies reveals an exponential
decay of these 'core states' with a decay length of 2.2(3) nm. The four-fold
symmetry sometimes predicted for d-wave vortices is not seen in spectroscopic
vortex images. A locally nodeless order parameter induced by the magnetic field
may be consistent with these measurements.

</DOC>
<DOC>
<DOCNO> 100025 </DOCNO>
On effective non-vanishing and base-point-freeness


  Let $X$ be a complete normal variety, $B$ an effective $\mathbb{R}$-divisor
on $X$, and $D$ a Cartier divisor on $X$. Assume that the pair $(X, B)$ is log
terminal. We consider the problem whether $H^0(X, D) \ne 0$ and obtain some
results in lower dimensions.

</DOC>
<DOC>
<DOCNO> 122060 </DOCNO>
Optical photometry of the UCM Lists I and II. II-B band surface


  We present Johnson B surface photometry for the UCM Survey galaxies.
One-dimensional bulge-disk decomposition is attempted, discussing on fitting
functions and computational procedures. The results from this decomposition,
jointly with concentration indices and an asymmetry coefficient, are employed
to study the morphological properties of these galaxies. We also compare our
results with the previous morphological classification established using Gunn r
imaging data and with other samples of galaxies. No major statistical
differences in morphology are found between red and blue data, although some
characteristics such as size and luminosity concentration vary. We find a
correlation between luminosity and size. Several parameters are used to
segregate the objects according to their morphological type.

</DOC>
<DOC>
<DOCNO> 99709 </DOCNO>
Dual group actions on C*-algebras and their description by Hilbert


  Given a C*-algebra $A$, a discrete abelian group $X$ and a homomorphism
$\Theta: X\to$ Out$A$ defining the dual action group $\Gamma\subset$ aut$A$,
the paper contains results on existence and characterization of Hilbert
$\{A,\Gamma\}$, where the action is given by $\hat{X}$. They are stated at the
(abstract) C*-level and can therefore be considered as a refinement of the
extension results given for von Neumann algebras for example by Jones
[Mem.Am.Math.Soc. 28 Nr 237 (1980)] or Sutherland [Publ.Res.Inst.Math.Sci. 16
(1980) 135]. A Hilbert extension exists iff there is a generalized 2-cocycle.
These results generalize those in [Commun.Math.Phys. 15 (1969) 173], which are
formulated in the context of superselection theory, where it is assumed that
the algebra $A$ has a trivial center, i.e. $Z=C1$. In particular the well-known
``outer characterization'' of the second cohomology $H^2(X,{\cal
U}(Z),\alpha_X)$ can be reformulated: there is a bijection to the set of all
$A$-module isomorphy classes of Hilbert extensions. Finally, a Hilbert space
representation (due to Sutherland in the von Neumann case) is mentioned. The
C*-norm of the Hilbert extension is expressed in terms of the norm of this
representation and it is linked to the so-called regular representation
appearing in superselection theory.

</DOC>
<DOC>
<DOCNO> 150380 </DOCNO>
Softly-Broken {\cal N} = 4 Supersymmetry in the Large-N Limit


  We calculate the exact values of the holomorphic observables of {\cal N}=4
supersymmetric SU(N) Yang-Mills theory deformed by mass terms which preserve
{\cal N}=1 SUSY. These include the chiral condensates in each massive vacuum of
the theory as well as the central charge which determines the tension of BPS
saturated domain walls interpolating between these vacua. Several unexpected
features emerge in the large-N limit, including anomalous modular properties
under an SL(2,Z) duality group which acts on a complexification of the 't Hooft
coupling \lambda=g^{2}N/4\pi. We discuss our results in the context of the
AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 118027 </DOCNO>
Pulsation in two Herbig Ae stars: HD 35929 and V351 Ori


  New photometric observations of seven intermediate mass pre-main sequence
delta Scuti candidates are presented. The periods and pulsation modes are
derived for two of these stars, namely HD 35929 and V351 Ori. The comparison
between observations and nonlinear pulsational models allows us to provide some
initial constraints on their mass and evolutionary state. As an illustration we
discuss the use of periods to identify the mode of pulsation in these two stars
and to have an independent estimate of their distances.

</DOC>
<DOC>
<DOCNO> 120440 </DOCNO>
Galaxy Mergers: A Search for Chemical Signatures


  We have gathered high resolution echelle spectra for more than two dozen
high-velocity metal-poor field stars, including BD+80 245, a star previously
known to have extremely low [alpha/Fe] abundances, as well as G4-36, a new
low-alpha star with unusually large [Ni/ Fe]. In this kinematically selected
sample, other chemically anomalous stars have also been uncovered. In addition
to deriving the alpha-element abundances, we have also analysed iron-group and
s-process elements. Not only does chemical substructure exist in the halo, but
the chemical anomalies are not all the same within all elemental groups.

</DOC>
<DOC>
<DOCNO> 70585 </DOCNO>
Existence of the $\sigma$-meson below 1 GeV and $f_0(1500)$ glueball


  On the basis of a simultaneous description of the isoscalar s-wave channel of
the $\pi\pi$ scattering (from the threshold up to 1.9 GeV) and of the
$\pi\pi\to K\bar{K}$ process (from the threshold to $\sim$ 1.4 GeV) in the
model-independent approach, a confirmation of the $\sigma$-meson at $\sim$ 665
MeV and an indication for the glueball nature of the $f_0(1500)$ state are
obtained. It is shown that the large $\pi\pi$-background, usually obtained,
combines, in reality, the influence of the left-hand branch-point and the
contribution of a very wide resonance at $\sim$ 665 MeV. The coupling constants
of the observed states with the $\pi\pi$ and $K\bar{K}$ systems and lengths of
the $\pi\pi$ and $K\bar{K}$ scattering are obtained.

</DOC>
<DOC>
<DOCNO> 11119 </DOCNO>
EPR effect in gravitational field: nature of non-locality


  The realization of the Einstein-Podolsky-Rosen effect by the correlation of
spin projections of two particles created in the decay of a single scalar
particle is considered for particles propagating in gravitational field. The
absence of a global definition of spatial directions makes it unclear whether
the correlation may exist in this case and, if yes, what directions in distant
regions must be correlated. It is shown that in a gravitational field an
approximate correlation may exist and the correlated directions are connected
with each other by the parallel transport along the world lines of the
particles. The reason for this is that the actual origin of the quantum
non-locality is founded in local processes.

</DOC>
<DOC>
<DOCNO> 121966 </DOCNO>
Successive Measurements of Cosmic-Ray Antiproton Spectrum in a Positive


  The energy spectrum of cosmic-ray antiprotons has been measured by BESS
successively in 1993, 1995, 1997 and 1998. In total, 848 antiprotons were
clearly identified in energy range 0.18 to 4.20 GeV. From these successive
measurements of the antiproton spectrum at various solar activity, we discuss
about the effect of the solar modulation and the origin of cosmic-ray
antiprotons. Measured antiproton ratios were nearly identical during this
period, and were consistent with a prediction taking the charge dependent solar
modulation into account.

</DOC>
<DOC>
<DOCNO> 121249 </DOCNO>
The X-ray Remnant of SN1987A


  We present high resolution Chandra observations of the remnant of SN1987A in
the Large Magellanic Cloud. The high angular resolution of the Chandra X-ray
Observatory (CXO) permits us to resolve the X-ray remnant. We find that the
remnant is shell-like in morphology, with X-ray peaks associated with some of
the optical hot spots seen in HST images. The X-ray light curve has departed
from the linear flux increase observed by ROSAT, with a 0.5-2.0 keV luminosity
of 1.5 x 10^35 erg/s in January 2000. We set an upper limit of 2.3 x 10^34
ergs/s on the luminosity of any embedded central source (0.5 - 2 keV). We also
present a high resolution spectrum, showing that the X-ray emission is thermal
in origin and is dominated by highly ionized species of O, Ne, Mg, and Si.

</DOC>
<DOC>
<DOCNO> 9876 </DOCNO>
Deformation and tribology of multi-walled hollow nanoparticles


  Multi-walled hollow nanoparticles made from tungsten disulphide (WS$_2$) show
exceptional tribological performance as additives to liquid lubricants due to
effective transfer of low shear strength material onto the sliding surfaces.
Using a scaling approach based on continuum elasticity theory for shells and
pairwise summation of van der Waals interactions, we show that van der Waals
interactions cause strong adhesion to the substrate which favors release of
delaminated layers onto the surfaces. For large and thin nanoparticles, van der
Waals adhesion can cause considerable deformation and subsequent delamination.
For the thick WS$_2$ nanoparticles, deformation due to van der Waals
interactions remains small and the main mechanism for delamination is pressure
which in fact leads to collapse beyond a critical value. We also discuss the
effect of shear flow on deformation and rolling on the substrate.

</DOC>
<DOC>
<DOCNO> 100759 </DOCNO>
The partnership of potentials in Quantum Mechanics and Shape Invariance


  The concept of partnership of potentials is studied in detail and in
particular the non-uniqueness due to the ambiguity in the election of the
factorization energy and in the choice of the solution of certain Riccati
equation. We generate new factorizations from old ones using invariance under
parameter transformations. The theory is illustrated with some examples.

</DOC>
<DOC>
<DOCNO> 122251 </DOCNO>
Stellar Populations in Dwarf Galaxies: A Review of the Contribution of


  This review aims to give an overview of the contribution of the Hubble Space
Telescope to our understanding of the detailed properties of Local Group dwarf
galaxies and their older stellar populations. The exquisite stable high spatial
resolution combined with photometric accuracy of images from the Hubble Space
Telescope have allowed us to probe further back into the history of star
formation of a large variety of different galaxy types with widely differing
star formation properties. We have learnt several important things about dwarf
galaxy evolution from these studies. Firstly we have found that no two galaxies
have identical star formation histories; some galaxies may superficially look
the same today, but they have invariably followed different paths to this
point. Now that we have managed to probe deep into the star formation history
of dwarf irregular galaxies in the Local Group it is obvious that there are a
number of similarities with the global properties of dwarf
elliptical/spheroidal type galaxies, which were previously thought to be quite
distinct. The previous strong dichotomy between these two classes has been
weakened by these new results and may stem from the differences in the
environment in which these similar mass galaxies were born into or have
inhabited for most of their lives. The more detailed is our understanding of
star formation processes and their effect on galaxy evolution in the nearby
Universe the better we will understand the results from studies of the
integrated light of galaxies in the high-redshift Universe.

</DOC>
<DOC>
<DOCNO> 150545 </DOCNO>
Branes and BPS Configurations of Non-Commutative/Commutative Gauge


  We study BPS Dirac monopole in U(1) gauge theory on non-commutative
spacetime. The corresponding brane configuration is obtained in the equivalent
ordinary gauge theory through the map proposed by Seiberg and Witten. This
configuration coincides exactly with a tilted D-string as predicted. This study
provides an interesting check of the equivalence of the non-commutative and
ordinary gauge theories.

</DOC>
<DOC>
<DOCNO> 13775 </DOCNO>
Comment on "Hole-Burning Experiments within Glassy Models with Infinite


  Comment on: L.F. Cugliandolo and J.L. Iguain; Phys. Rev. Lett. {\bf 85} 3448
(2000)

</DOC>
<DOC>
<DOCNO> 10941 </DOCNO>
The K-sat problem in a simple limit


  We compute the thermodynamic properties of the 3-satisfiability problem in
the infinite connectivity limit. In this limit the computations can be strongly
simplified and the thermodynamical properties can be obtained with an high
accuracy. We find evidence for a continuous replica symmetry breaking in the
region of high number of clauses, $\alpha > \alpha_c$.

</DOC>
<DOC>
<DOCNO> 8824 </DOCNO>
Competing orders and quantum criticality in doped antiferromagnets


  We use a number of large-N limits to explore the competition between ground
states of square lattice doped antiferromagnets which break electromagnetic
U(1), time-reversal, or square lattice space group symmetries. Among the states
we find are d-, (s+id)-, and (d+id)-wave superconductors, Wigner crystals,
Wigner crystals of hole pairs, orbital antiferromagnets (or staggered-flux
states), and states with spin-Peierls and bond-centered charge stripe order. In
the vicinity of second-order quantum phase transitions between the states, we
go beyond the large-N limit by identifying the universal quantum field theories
for the critical points, and computing the finite temperature, quantum-critical
damping of fermion spectral functions. We identify candidate critical points
for the recently observed quantum-critical behavior in photoemission
experiments on BSCCO by Valla et al. (Science 285, 2110 (1999)). These involve
onset of a charge density wave, or of broken time-reversal symmetry with (d+id)
or (s+id) pairing, in a d-wave superconductor. It is not required (although it
is allowed) that the stable state in the doped cuprates to be anything other
than the d-wave superconductor---the other states need only be stable nearby in
parameter space. At finite temperatures, fluctuations associated with these
nearby states lead to the observed fermion damping in the vicinity of the nodal
points in the Brillouin zone. The cases with broken time-reversal symmetry are
appealing because the order parameter is not required to satisfy any special
commensurability conditions. The observed absence of inelastic damping of
quasiparticles with momenta (pi,k), (k,pi) (with 0 < k < pi) also appears very
naturally for the case of a transition to (d+id) order.

</DOC>
<DOC>
<DOCNO> 170106 </DOCNO>
Secure key distribution via pre- and post-selected quantum states


  A quantum key distribution scheme whose security depends on the features of
pre- and post-selected quantum states is described.

</DOC>
<DOC>
<DOCNO> 99678 </DOCNO>
Lifts of smooth group actions to line bundles


  Let X be a compact manifold with a smooth action of a compact connected Lie
group G. Let $L\to X$ be a complex line bundle. Using the Cartan complex for
equivariant cohomology, we give a new proof of a theorem of Hattori and Yoshida
which says that the action of G lifts to L if and only if the first Chern class
$c\sb 1(L)$ of L can be lifted to an integral equivariant cohomology class in
$H\sp 2\sb G(X;\ZZ)$, and that the different lifts of the action are classified
by the lifts of $c\sb 1(L)$ to $H\sp 2\sb G(X;\ZZ)$. As a corollary of our
method of proof, we prove that, if the action is Hamiltonian and $\nabla$ is a
connection on L which is unitary for some metric on L and whose curvature is
G-invariant, then there is a lift of the action to a certain power $L\sp d$
(where d is independent of L) which leaves fixed the induced metric on $L^d$
and the connection $\nabla\sp{\otimes d}$. This generalises to symplectic
geometry a well known result in Geometric Invariant Theory.

</DOC>
<DOC>
<DOCNO> 121280 </DOCNO>
Wide Field Imaging at 250 GHz


  We summarize results from sensitive, wide-field imaging at 250 GHz using the
Max-Planck Bolometer Array at the IRAM 30m telescope, including source counts,
clustering, and redshift distribution.

</DOC>
<DOC>
<DOCNO> 70393 </DOCNO>
The use of configuration interaction method for describing fine-


  The screened quasi-relativistic potential is used for describing spin-orbit
splitting in $^{3}P_{J}$ waves of quark-antiquark system. Fermi-Breit equation
is solved numerically in configuration interaction approximation. This
approximation takes into account the mixing of wave functions up to fifth order
and corrects substantially perturbation calculations. The nature of potentials
Lorenz transformation property is elucidated. Very good quantitative results
for $b\bar{b}$ and $c\bar{c}$ quarkonia and quite acceptable qualitative
characteristics as well as for systems with unequal masses are obtained for
$u\bar{u}$.

</DOC>
<DOC>
<DOCNO> 80837 </DOCNO>
The Mass of the b Quark from Lattice NRQCD


  We present results for the mass of the $b$ quark in the $\bar{MS}$ scheme
obtained by calculating the binding energy of the $B$ meson in the static
limit. The self energy of a static quark, $E_0^\infty$ needed for this purpose,
is now known to $O(\alpha^3)$ in the quenched approximation. We find a {\it
preliminary} value of $\bar{m_b}(\bar{m_b})=4.34(7)$ GeV at $n_f=0$. The error
is dominated by the remaining uncertainty in $E_0^\infty$. In addition, using
$E_0^\infty$ at $O(\alpha^2)$, we estimate that the quark mass is reduced by
approximately 70 MeV when two flavours of dynamical quarks are introduced.

</DOC>
<DOC>
<DOCNO> 121256 </DOCNO>
Galactic Morphologies in Distant Clusters


  The abundance of elliptical, S0 and spiral galaxies in clusters is presented
as a function of redshift comparing the results of the HST distant cluster
studies with new data at z~0.2 and with the standard local comparison samples.
This analysis confirms and strengthens the conclusion that the proportion of S0
galaxies increases toward lower redshifts at the expense of the spiral
population. The dependence of the relative occurrence of S0s and ellipticals
and of the morphology-density relation on the cluster concentration are also
discussed.

</DOC>
<DOC>
<DOCNO> 85540 </DOCNO>
2D gravity without test particles is pointless (Comment on


  Claims of a general Weyl invariance of an arbitrary 2D dilaton theory are
critically discussed.

</DOC>
<DOC>
<DOCNO> 10459 </DOCNO>
Calorimetric study of thermal properties of superconducting tapes :


  The method consists in the monitoring of the temperature variation of a
superconductor tape subjected to a trapezoidal current pulse. Simulations of
the experiment were performed using the lumped capacitance model and also the
finite element method. The former reproduces the sample's reaction for the
increasing and decreasing parts of the pulse. The same can be said for the
finite element method but the decreasing temperature as expected is not
adequately reproduced. Treating the problem in two dimensions rather than one
should correct the situation. Nethertheless we obtained a thermal conductivity
consistent with the literature.

</DOC>
<DOC>
<DOCNO> 100542 </DOCNO>
Shimura curve computations


  We give some methods for computing equations for certain Shimura curves,
natural maps between them, and special points on them. We then illustrate these
methods by working out several examples in varying degrees of detail. For
instance, we compute coordinates for all the rational CM points on the curves
"X(1)" associated with the quaternion algebras over Q ramified at {2,3}, {2,5},
{2,7}, and {3,5}. We conclude with a list of open questions that may point the
way to further computational investigation of these curves.

</DOC>
<DOC>
<DOCNO> 71767 </DOCNO>
Tunneling Phenomena in Cosmology: Some Fundamental Problems


  The fundamental problem of how tunneling in thermal medium is completed is
addressed, and a new time scale of order 1/friction for its termination, which
is usually much shorter than the Hubble time, is pointed out. Enhanced
non-linear resonance is responsible for this short time scale. This phenomenon
occurs when the semiclassical periodic motion in a metastable potential well
resonates with one of the environment harmonic oscillators coupled to its
motion.

</DOC>
<DOC>
<DOCNO> 178483 </DOCNO>
Solution of the Skyrme-Hartree-Fock equations in the Cartesian deformed


  We describe the new version (v1.75r) of the code HFODD which solves the
nuclear Skyrme-Hartree-Fock problem by using the Cartesian deformed
harmonic-oscillator basis. Three minor errors that went undetected in the
previous version have been corrected. The new version contains an interface to
the LAPACK subroutine ZHPEV. Several methods of terminating the Hartree-Fock
iteration procedure, and an algorithm that allows to follow the diabatic
configurations, have been implemented.

</DOC>
<DOC>
<DOCNO> 70657 </DOCNO>
Problems with the Casimir Vacuum Energy


  A critical look is taken at the calculation of the Casimir effect. The
boundary conditions play an important role and should be imposed in a physical
way. An acceptable result for the vacuum energy is only obtained when different
regularization schemes yield the same result. Radiative corrections to the
Casimir force between two parallel plates due to electromagnetic vacuum
fluctuations have been obtained both in full QED and in a low-energy, effective
field theory with conflicting results. Including surface terms in the effective
Lagrangian, the QED result can be understood. Finally, a problem with the
electromagnetic vacuum energy on $S^3$ is pointed out and a solution suggested.
The structure of higher order corrections to this result is discussed.

</DOC>
<DOC>
<DOCNO> 12173 </DOCNO>
Disorder and Two-Particle Interaction in Low-Dimensional Quantum Systems


  We review some of the recent results on two-interacting particles (TIP) in
low-dimensional disordered quantum models. Special attention is given to the
mapping of the problem onto random band matrices. In particular, we construct
two simple, seemingly closely related examples for which an analogous mapping
leads to incorrect results. We briefly discuss possible reasons for this
discrepancy based on the physical differences between the TIP problem and our
examples.

</DOC>
<DOC>
<DOCNO> 122069 </DOCNO>
Spatiotemporal fragmentation as a mechanism for different dynamical


  Recent analyses of the helioseismic observations indicate that the previously
observed surface torsional oscillations with periods of about 11 years extend
significantly downwards into the solar convective zone. Furthermore, there are
indications that the dynamical regimes at the base of the convection zone are
different from those observed at the top, having either significantly shorter
periods or non-periodic behaviour.
  We propose that this behaviour can be explained by the occurrence of {\it
spatiotemporal fragmentation}, a crucial feature of which is that such
behaviour can be explained solely through nonlinear spatiotemporal dynamics,
without requiring separate mechanisms with different time scales at different
depths.
  We find evidence for this mechanism in the context of a two dimensional
axisymmetric mean field dynamo model operating in a spherical shell, with a
semi-open outer boundary condition, in which the only nonlinearity is the
action of the azimuthal component of the Lorentz force of the dynamo generated
magnetic field on the solar angular velocity.

</DOC>
<DOC>
<DOCNO> 122397 </DOCNO>
The K-Band Galaxy Luminosity Function


  We measured the K-band luminosity function using a complete sample of 4192
morphologically-typed 2MASS galaxies with 7 < K < 11.25 mag spread over 2.12
str. Early-type (T < -0.5) and late-type (T > -0.5) galaxies have similarly
shaped luminosity functions, alpha_e=-0.92+/-0.10 and alpha_l=-0.87+/-0.09. The
early-type galaxies are brighter, M_*e=-23.53+/-0.06 mag compared to
M_*l=-22.98\pm0.06 mag, but less numerous, n_*e=(0.0045+/-0.0006)h^3/Mpc^3
compared to n_*l=(0.0101+/-0.0013)h^3/Mpc^3 for H_0=100h km/s Mpc, such that
the late-type galaxies slightly dominate the K-band luminosity density,
j_late/j_early=1.17+/-0.12. Our morphological classifications are internally
consistent, consistent with previous classifications and lead to luminosity
functions unaffected by the estimated uncertainties in the classifications.
These luminosity functions accurately predict the K-band number counts and
redshift distributions for K < 18 mag, beyond which the results depend on
galaxy evolution and merger histories.

</DOC>
<DOC>
<DOCNO> 119296 </DOCNO>
Star formation in clusters: early sub-clustering in the Serpens core


  We present high resolution interferometric and single dish observations of
molecular gas in the Serpens cluster-forming core. Star formation does not
appear to be homogeneous throughout the core, but is localised in spatially-
and kinematically-separated sub-clusters. The stellar (or proto-stellar)
density in each of the sub-clusters is much higher than the mean for the entire
Serpens cluster. This is the first observational evidence for the hierarchical
fragmentation of proto-cluster cores suggested by cluster formation models.

</DOC>
<DOC>
<DOCNO> 150457 </DOCNO>
BPS states carrying fermionic brane charges


  The Green-Siegel central extension of superalgebras for BPS branes is
studied. In these cases commutators of usual bosonic brane charges only with
the broken supersymmetry charges allow this central extension. We present an
interpretation of these fermionic central charges as fermionic brane charges,
and show that they take nonzero values for a nontrivial fermionic boundary
condition. Such fermionic coordinates solutions are determined by equations of
motion in a suitable gauge condition which manifests Nambu-Goldstone fermionic
modes as well as bosonic modes in the static gauge. We also show that some
modes of dilatino fields couple with the fermionic brane currents.

</DOC>
<DOC>
<DOCNO> 169747 </DOCNO>
Classical and quantum mechanics on information spaces with applications


  We use the system of p-adic numbers for the description of information
processes. Basic objects of our models are so called transformers of
information, basic processes are information processes, the statistics are
information statistics (thus we present a model of information reality). The
classical and quantum mechanical formalisms on information p-adic spaces are
developed. It seems that classical and quantum mechanical models on p-adic
information spaces can be applied for the investigation of flows of information
in cognitive and social systems, since a p-adic metric gives quite natural
description of the ability to form associations.

</DOC>
<DOC>
<DOCNO> 120000 </DOCNO>
Approximate expressions for polar gap electric field of pulsars


  We derive easy-to-handle approximations for the polar gap electric field due
to inertial frame dragging as derived by Harding & Muslimov 1998. A simple
formula valid for polar gap height comparable to the polar cap radius is
presented.

</DOC>
<DOC>
<DOCNO> 11966 </DOCNO>
Charge to Magnetic Flux Ratios


  It is shown that if the carriers in the fractional quantum Hall effect are
taken as geometrical excitations with quanta of charge e and magnetic flux
h/2e, as proposed in a previous publication, the calculated results are
compatible with the series of fractions obtained experimentally.

</DOC>
<DOC>
<DOCNO> 102682 </DOCNO>
A Spectral Quadruple for de Sitter Space


  A set of data supposed to give possible axioms for spacetimes with a
sufficient number of isometries in spectral geometry is given. These data are
shown to be sufficient to obtain 1+1 dimensional de Sitter spacetime. The data
rely at the moment somewhat on the guidance given by a required symmetry, in
part to allow explicit calculations in a specific model. The framework applies
also to the noncommutative case. Finite spectral triples are discussed as an
example.

</DOC>
<DOC>
<DOCNO> 178804 </DOCNO>
Parity Violation in Polarized-Gamma Proton Compton Scattering


  Polarized beam gamma p Compton scattering provides a theoretically clean way
to extract the isovector parity violating pion-nucleon coupling constant
$h_{\pi NN}^{(1)}$. This channel is more tractable experimentally than the
recently proposed extraction of $h_{\pi NN}^{(1)}$ from the Bedaque-Savage
process --- polarized target gamma p compton scattering. The leading parity
violating effect is calculated using Heavy Baryon Chiral Perturbation Theory.
The size of the asymmetry is estimated to be ~ 4 10^{-8} for 120 MeV photon
energy.

</DOC>
<DOC>
<DOCNO> 8368 </DOCNO>
Stability analysis of the D-dimensional nonlinear Schroedinger equation


  Considering the static solutions of the D-dimensional nonlinear Schroedinger
equation with trap and attractive two-body interactions, the existence of
stable solutions is limited to a maximum critical number of particles, when D
is greater or equal 2. In case D=2, we compare the variational approach with
the exact numerical calculations. We show that, the addition of a positive
three-body interaction allows stable solutions beyond the critical number. In
this case, we also introduce a dynamical analysis of the conditions for the
collapse.

</DOC>
<DOC>
<DOCNO> 121242 </DOCNO>
Resonant capture by inward migrating planets


  We investigate resonant capture of small bodies by planets that migrate
inwards, using analytic arguments and three-body integrations. If the orbits of
the planet and the small body are initially circular and coplanar, the small
body is captured when it crosses the 2:1 resonance with the planet. As the
orbit shrinks it becomes more eccentric, until by the time its semimajor axis
has shrunk by a factor of four, its eccentricity reaches nearly unity
(1-e<<10^{-4}). In typical planetary systems, bodies in this high-eccentricity
phase are likely to be consumed by the central star. If they can avoid this
fate, as migration continues the inclination flips from 0 to i=180 degrees;
thereafter the eccentricity declines until the semimajor axis is a factor of
nine smaller than at capture, at which point the small body is released from
the 2:1 resonance on a nearly circular retrograde orbit. Small bodies captured
into resonance from initially inclined or eccentric orbits can also be ejected
from the system, or released from the resonance on highly eccentric polar
orbits (i\simeq 90 degrees) that are stabilized by a secular resonance. We
conclude that migration can drive much of the inner planetesimal disk into the
star, and that post-migration multi-planet systems may not be coplanar.

</DOC>
<DOC>
<DOCNO> 12572 </DOCNO>
Spin-Peierls instability in a quantum spin chain with


  We analysed the ground state energy of some dimerized spin-1/2 transverse XX
and Heisenberg chains with Dzyaloshinskii-Moriya (DM) interaction to study the
influence of the latter interaction on the spin-Peierls instability. We found
that DM interaction may act either in favour of the dimerization or against it.
The actual result depends on the dependence of DM interaction on the distortion
amplitude in comparison with such dependence for the isotropic exchange
interaction.

</DOC>
<DOC>
<DOCNO> 9648 </DOCNO>
Linear response conductance and magneto-resistance of ferromagnetic


  The current through ferromagnetic single-electron transistors (SET's) is
considered. Using path integrals the linear response conductance is formulated
as a function of the tunnel conductance vs. quantum conductance and the
temperature vs. Coulomb charging energy. The magneto-resistance of
ferromagnet-normal metal-ferromagnet (F-N-F) SET's is almost independent of the
Coulomb charging energy and is only reduced when the transport dwell time is
longer than the spin-flip relaxation time. In all-ferromagnetic (F-F-F) SET's
with negligible spin-flip relaxation time the magneto-resistance is calculated
analytically at high temperatures and numerically at low temperatures. The
F-F-F magneto-resistance is enhanced by higher order tunneling processes at low
temperatures in the 'off' state when the induced charges vanishes. In contrast,
in the 'on' state near resonance the magneto-resistance ratio is a
non-monotonic function of the inverse temperature.

</DOC>
<DOC>
<DOCNO> 121895 </DOCNO>
Scientific impact of large telescopes


  The scientific impacts of telescopes worldwide have been compared on the
basis of their contributions to (a) the 1000 most-cited astronomy papers
published 1991-8 (125 from each year), and (b) the 452 astronomy papers
published in Nature 1989-98. 1-m and 2-m ground-based telescopes account for ~
5% of the citations to the top-cited papers, 4-m telescopes 10%, Keck I/II 4%,
sub-mm and radio telescopes 4%, HST 8%, other space telescopes 23%. The
remaining citations are mainly to theoretical and review papers. The strong
showing by 1-m and 2-m telescopes in the 1990s augurs well for the continued
scientific impact of 4-m telescopes in the era of 8-m telescopes. The impact of
individual ground-based optical telescopes is proportional to collecting area
(and approximately proportional to capital cost). The impacts of the various
4-m telescopes are similar, with CFHT leading in citation counts, and WHT in
Nature papers. HST has about 15 times the citation impact of a 4-m ground-based
telescope, but cost > 100 times as much. Citation counts are proportional to
counts of papers published in Nature, but for radio telescopes the ratio is a
factor ~ 3 smaller than for optical telescopes, highlighting the danger of
using either metric alone to compare the impacts of different types of
telescope. Breakdowns of citation counts by subject (52% extragalactic), and
journal (ApJ 44%, Nature 11%, MNRAS 9%, A&A 6%) are also presented.

</DOC>
<DOC>
<DOCNO> 120336 </DOCNO>
Spectral energy distributions of FRI nuclei and the FRI/BL Lac unifying


  We consider archival ROSAT and HST observations of five FRI radio galaxies
and isolate their nuclear emission from that of the host galaxy. This enable us
to determine the Spectral Energy Distributions (SED) of their nuclei spanning
from the radio to the X-ray band. They cannot be described as single power-laws
but require the presence of an emission peak located between the IR and soft
X-ray band. We found consistency between the SED peak position and the values
of the broad band spectral indices of radio galaxies with those of BL Lac, once
the effects of beaming are properly taken into account. FRI SED are thus
qualitatively similar to those of BL Lacs supporting the identification of FRI
sources as their mis-oriented counterparts. No dependence of the shape of the
SED on the FR~I orientation is found.

</DOC>
<DOC>
<DOCNO> 10679 </DOCNO>
Correlation gap in the optical spectra of the two-dimensional organic


  Optical reflection measurements within the highly conducting (a,b)-plane of
the organic metal (BEDT-TTF)_4[Ni(dto)_2] reveal the gradual development of a
sharp feature at around 200 cm as the temperature is reduced below 150 K. Below
this frequency a narrow Drude-like response is observed which accounts for the
metallic behavior. Since de Haas-von Alphen oscillations at low temperatures
confirm band structure calculations of bands crossing the Fermi energy, we
assign the observed behavior to a two-dimensional metallic state in the
proximity of a correlation induced metal-insulator transition.

</DOC>
<DOC>
<DOCNO> 9808 </DOCNO>
The existence of the fine electronic structure in LaCoO3


  We argue that in LaCoO3 exists the fine electronic structure associated with
the atomic-like states of the Co3+ ions and caused by the crystal-field and
intra-atomic spin-orbit interactions. This low-energy fine electronic structure
has to be taken into account for any meaningful analysis of electronic and
magnetic properties of LaCoO3.

</DOC>
<DOC>
<DOCNO> 11928 </DOCNO>
Comment on ``Determination of Interlayer Diffusion Parameters for


  A Comment on PRL 85, 1480 (2000) by K.R. Roos and M.C. Tringides.

</DOC>
<DOC>
<DOCNO> 152019 </DOCNO>
Dimensional and Dynamical Aspects of the Casimir Effect: Understanding


  Zero-point fluctuations in quantum fields give rise to observable forces
between material bodies, the so-called Casimir forces. In this lecture I
present some results of the theory of the Casimir effect, primarily formulated
in terms of Green's functions. There is an intimate relation between the
Casimir effect and van der Waals forces. Applications to conductors and
dielectric bodies of various shapes will be given for the cases of scalar,
electromagnetic, and fermionic fields. The dimensional dependence of the effect
will be described. Finally, we ask the question: Is there a connection between
the Casimir effect and the phenomenon of sonoluminescence?

</DOC>
<DOC>
<DOCNO> 83509 </DOCNO>
A Benchmark for Image Retrieval using Distributed Systems over the


  The performance of CBIR algorithms is usually measured on an isolated
workstation. In a real-world environment the algorithms would only constitute a
minor component among the many interacting components. The Internet
dramati-cally changes many of the usual assumptions about measuring CBIR
performance. Any CBIR benchmark should be designed from a networked systems
standpoint. These benchmarks typically introduce communication overhead because
the real systems they model are distributed applications. We present our
implementation of a client/server benchmark called BIRDS-I to measure image
retrieval performance over the Internet. It has been designed with the trend
toward the use of small personalized wireless systems in mind. Web-based CBIR
implies the use of heteroge-neous image sets, imposing certain constraints on
how the images are organized and the type of performance metrics applicable.
BIRDS-I only requires controlled human intervention for the compilation of the
image collection and none for the generation of ground truth in the measurement
of retrieval accuracy. Benchmark image collections need to be evolved
incrementally toward the storage of millions of images and that scaleup can
only be achieved through the use of computer-aided compilation. Finally, our
scoring metric introduces a tightly optimized image-ranking window.

</DOC>
<DOC>
<DOCNO> 122790 </DOCNO>
The Infrared Surface Brightness Fluctuation Hubble Constant


  We measured infrared surface brightness fluctuation (SBF) distances to an
isotropically-distributed sample of 16 distant galaxies with redshifts reaching
10,000 km/s using the near-IR camera and multi-object spectrometer (NICMOS) on
the Hubble Space Telescope (HST). The excellent spatial resolution, very low
background, and brightness of the IR fluctuations yielded the most distant SBF
measurements to date. Twelve nearby galaxies were also observed and used to
calibrate the F160W (1.6 micron) SBF distance scale. Of these, three have
Cepheid variable star distances measured with HST and eleven have optical
I-band SBF distance measurements. A distance modulus of 18.5 mag to the Large
Magellanic Cloud was adopted for this calibration. We present the F160W SBF
Hubble diagram and find a Hubble constant Ho=76 +/- 1.3 (1-sigma statistical)
+/- 6 (systematic) km/s/Mpc. This result is insensitive to the velocity model
used to correct for local bulk motions. Restricting the fit to the six most
distant galaxies yields the smallest value of Ho=72 +/- 2.3 km/s/Mpc consistent
with the data. This 6% decrease in the Hubble constant is consistent with the
hypothesis that the Local Group inhabits an under-dense region of the universe,
but is also consistent with the best-fit value of Ho=76 km/s/Mpc at the
1.5-sigma level.

</DOC>
<DOC>
<DOCNO> 151455 </DOCNO>
Non-Linear Electrodynamics in Curved Backgrounds


  We study non-linear electrodynamics in curved space from the viewpoint of
dualities. After establishing the existence of a topological bound for
self-dual configurations of Born-Infeld field in curved space, we check that
the energy-momentum tensor vanishes. These properties are shown to hold for
general duality-invariant non-linear electrodynamics. We give the dimensional
reduction of Born-Infeld action to three dimensions in a general curved
background admitting a Killing vector. The SO(2) duality symmetry becomes
manifest but other symmetries present in flat space are broken, as is U-duality
when one couples to gravity. We generalize our arguments on duality to the case
of n U(1) gauge fields, and present a new Lagrangian possessing SO(n) X
SO(2)_elemag duality symmetry. Other properties of this model such as Legendre
duality and enhancement of the symmetry by adding dilaton and axion, are
studied. We extend our arguments to include a background b-field in the curved
space, and give new examples including almost Kaehler manifolds and
Schwarzshild black holes with a $b$-field.

</DOC>
<DOC>
<DOCNO> 69595 </DOCNO>
Theory and Phenomenology of Type I strings and M-theory


  The physical motivations and the basic construction rules for Type I strings
and M-theory compactifications are reviewed in light of the recent
developments. The first part contains the basic theoretical ingredients needed
for building four-dimensional supersymmetric models, models with broken
supersymmetry and for computing low-energy actions and quantum corrections to
them. The second part contains some phenomenological applications to brane
world scenarios with low values of the string scale and large extra dimensions.

</DOC>
<DOC>
<DOCNO> 119707 </DOCNO>
Is MS1054-03 an exceptional cluster? A new investigation of ROSAT/HRI


  We reanalyzed the ROSAT/HRI observation of MS1054-03, optimizing the channel
HRI selection and including a new exposure of 68 ksec. From a wavelet analysis
of the HRI image we identify the main cluster component and find evidence for
substructure in the west, which might either be a group of galaxies falling
onto the cluster or a foreground source. Our 1-D and 2-D analysis of the data
show that the cluster can be fitted well by a classical betamodel centered only
20arcsec away from the central cD galaxy. The core radius and beta values
derived from the spherical model(beta = 0.96_-0.22^+0.48) and the elliptical
model (beta = 0.73+/-0.18) are consistent. We derived the gas mass and total
mass of the cluster from the betamodel fit and the previously published ASCA
temperature (12.3^{+3.1}_{-2.2} keV). The gas mass fraction at the virial
radius is fgas = (14[-3,+2.5]+/-3)% for Omega_0=1, where the errors in brackets
come from the uncertainty on the temperature and the remaining errors from the
HRI imaging data. The gas mass fraction computed for the best fit ASCA
temperature is significantly lower than found for nearby hot clusters,
fgas=20.1pm 1.6%. This local value can be matched if the actual virial
temperature of MS1054-032 were close to the lower ASCA limit (~10keV) with an
even lower value of 8 keV giving the best agreement. Such a bias between the
virial and measured temperature could be due to the presence of shock waves in
the intracluster medium stemming from recent mergers. Another possibility, that
reconciles a high temperature with the local gas mass fraction, is the
existence of a non zero cosmological constant.

</DOC>
<DOC>
<DOCNO> 169643 </DOCNO>
Induced coherence with and without induced emission


  We analyze signal coherence in the setup of Wang, Zou and Mandel, where two
optical downconverters have indistinct idler modes. Quantum interference,
caused by indistinguishability of paths, has a visibility proportional to the
transmission amplitude between idlers. Classical interference, caused by
induced emission, may be complete for any finite transmission.

</DOC>
<DOC>
<DOCNO> 122592 </DOCNO>
Enhanced interactions, mergers and starbursts in dense cluster


  Optical and X-ray studies have established the prevalence of significant
substructure in clusters of galaxies, indicating that clusters are young
systems, and that recent major mergers have occurred in many clusters.
Numerical simulations show that sub-cluster merging will result in significant
tidal forces on disk galaxies in accreting sub-groups, which is likely to lead
to the transformation of spirals to S0s in clusters. Simulations predict
simultaneous moderate starbursts in gas-rich disk galaxies in clusters which
show on-going or recent merger activity, as well as enhanced galaxy-galaxy
interactions and mergers. Observational data from studies of spectral
indicators, both of starburst activity in late-type galaxies in nearby
clusters, and of poststarburst activity in early-type galaxies in nearby and
intermediate redshift clusters, support this scenario.

</DOC>
<DOC>
<DOCNO> 178880 </DOCNO>
Fock exchange terms in non-linear Quantum Hadrodynamics


  We propose a method to introduce Fock term contributions in relativistic
models of fermions coupled to mesons, including self-interactions for the
mesonic fields. We show that effects on equilibrium properties and on the
dynamical response of the fermionic system can be consistently accounted for.
Some implications on equilibrium properties of asymmetric nuclear matter are
discussed.

</DOC>
<DOC>
<DOCNO> 68407 </DOCNO>
Bottom Production Asymmetries at the LHC


  We present results on bottom hadron production asymmetries at the LHC within
both the Lund string fragmentation model and the intrinsic bottom model. The
main aspects of the models are summarized and specific predictions for pp
collisions at 14 TeV are given. Asymmetries are found to be very small at
central rapidities increasing to a few percent at forward rapidities. At very
large rapidities intrinsic production could dominate but this region is
probably out of reach of any experiment.

</DOC>
<DOC>
<DOCNO> 119818 </DOCNO>
The stars near the centre of supergiant shell LMC4: Further constraints


  The huge supergiant shell (SGS) LMC4, next to the giant HII region 30 Doradus
the second most impressive feature of the Large Magellanic Cloud (LMC), has
been the subject of many studies and was used to test various models of star
forming mechanisms. In this paper we present a B, V photometry of the very
centre of this SGS. The new data yield an age of 11(2)Myr and a colour excess
E(B-V) = 0.10(3)mag. Additionally, the two clusters near the geometric centre
are too old to be related to the formation of LMC4: HS343 being ~0.1Gyr and
KMHK1000 being ~0.3Gyr of age. This and existing photometries support that the
young stellar population covering the entire inner region is nearly coeval. We
compare these findings with predictions of models proposed for the creation
mechanism of SGSs. We conclude that the large-scale trigger, necessary to
explain the observations, comes from hydrodynamic interaction of the galactic
halo with gas in the leading edge of the moving LMC.

</DOC>
<DOC>
<DOCNO> 174585 </DOCNO>
First decay study of the very neutron-rich isotope Br-93


  The decay of the mass-separated, very neutron-rich isotope Br-93 has been
studied by gamma-spectroscopy. A level scheme of its daughter Kr-93 has been
constructed. Level energies, gamma-ray branching ratios and multipolarities
suggest spins and parities which are in accord with a smooth systematics of the
N=57 isotones for Z less-equal 40, suggesting the N=56 shell closure still to
be effective in Kr isotopes. So far, there is no indication of a progressive
onset of deformation in neutron-rich Kr isotopes.

</DOC>
<DOC>
<DOCNO> 178711 </DOCNO>
Hanbury Brown-Ttiss Correlation Functions from Event Generators: A


  Employing NEXUS, one of the most recent simulation programs for heavy ions
collisions, we investigate in detail the Hanbury-Twiss correlation function for
charged pions for reactions 158 GeV Pb+Pb. For this study we supplement the
standard simulation program by electromagnetic interactions. We find that the
string fragmentation introduces strong space-momentum correlations and the
freeze out times of the correlated pairs have a wide distribution. Both has a
strong influence on the apparent source radius determined from the measured
correlation correlation function.An equally strong influence is observed for
the final state electromagnetic interaction.

</DOC>
<DOC>
<DOCNO> 99433 </DOCNO>
Deformations of algebras over operads and Deligne's conjecture


  In present paper we develop the deformation theory of operads and algebras
over operads. Free resolutions (constructed via Boardman-Vogt approach) are
used in order to describe formal moduli spaces of deformations. We apply the
general theory to the proof of Deligne's conjecture. The latter says that the
Hochschild complex of an associative algebra carries a canonical structure of a
dg-algebra over the chain operad of the little discs operad. In the course of
the proof we construct an operad of geometric nature which acts on the
Hochschild complex. It seems to be different from the brace operad (the latter
was used in the previous approaches to the Deligne's conjecture). It follows
from our results that the Grothendieck-Teichm\"uller group acts (homotopically)
on the moduli space of structures of 2-algebras on the Hochschild complex. In
the Appendix we develop a theory of piecewise algebraic chains and forms. It is
suitable for real semialgebraic manifolds with corners (like Fulton-Macpherson
compactifications of the configuration spaces of points).

</DOC>
<DOC>
<DOCNO> 119855 </DOCNO>
Median Statistics, H_0, and the Accelerating Universe


  (Abridged) We develop median statistics that provide powerful alternatives to
chi-squared likelihood methods and require fewer assumptions about the data.
Applying median statistics to Huchra's compilation of nearly all estimates of
the Hubble constant, we find a median value H_0=67 km/s/Mpc. Median statistics
assume only that the measurements are independent and free of systematic
errors. This estimate is arguably the best summary of current knowledge because
it uses all available data and, unlike other estimates, makes no assumption
about the distribution of measurement errors. The 95% range of purely
statistical errors is +/- 2 km/s/Mpc. The statistical precision of this result
leads us to analyze the range of possible systematic errors in the median,
which we estimate to be roughly +/- 5 km/s/Mpc (95% limits), dominating over
the statistical errors. A Bayesian median statistics treatment of high-redshift
Type Ia supernovae (SNe Ia) apparent magnitude versus redshift data from Riess
et al. yields a posterior probability that the cosmological constant Lambda > 0
of 70 or 89%, depending on the prior information used. The posterior
probability of an open universe is about 47%. Analysis of the Perlmutter et al.
high-redshift SNe Ia data show the best-fit flat-Lambda model favored over the
best-fit Lambda = 0 open model by odds of 366:1; corresponding Riess et al.
odds are 3:1 (assuming prior odds of 1:1).Median statistics analyses of the SNe
Ia data do not rule out a time-variable Lambda model, and may even favor it
over a time-independent Lambda and a Lambda = 0 open model.

</DOC>
<DOC>
<DOCNO> 117354 </DOCNO>
Long-term Variability Properties and Periodicity Analysis for Blazars


  In this paper, the compiled long-term optical and infrared measurements of
some blazars are used to analyze the variation properties and the optical data
are used to search for periodicity evidence in the lightcurve by means of the
Jurkevich technique and the discrete correlation function (DCF) method.
Following periods are found: 4.52-year for 3C 66A; 1.56 and 2.95 years for AO
0235+164;
 14.4, 18.6 years for PKS 0735+178; 17.85 and 24.7 years for PKS 0754+100; 5.53
and 11.75 for OJ 287. 4.45, and 6.89 years for PKS 1215; 9 and 14.84 years for
PKS 1219+285;
 2.0, 13.5 and 22.5 for 3C273; 7.1 year for 3C279;
 6.07 for PKS 1308+326; 3.0 and 16.5 years for PKS 1418+546;
 2.0 and 9.35 years for PKS 1514-241; 18.18 for PKS 1807+698;
 4.16 and 7.0 for 2155-304; 14 and 20 years for BL Lacertae. Some explanations
have been discussed.

</DOC>
<DOC>
<DOCNO> 11108 </DOCNO>
A Priori Approach to Calculation of Energies of Solvation


  We propose a systematic, {\em a priori} approach to the problem of the
calculation of solvation energies using continuum dielectric models coupled to
quantum mechanical description of reacting molecules. Our method does not rely
on empirically scaled van der Waals radii to create a dielectric cavity, but
rather uses the electron density of the reactants as the physical variable
describing the cavity. In addition, the precise choice of cavity is made by
ensuring that the dielectric reproduces the correct linear response of the
solvent to electrostatic perturbations. As a model application which is
interesting in its own right, we study the hydrolysis of methylene chloride, a
representative model waste compound in supercritical oxidation experiments, and
which has shown surprising solvation effects close to the critical point of
pure water (T=394$^o$ C, P=221 bar). Using our {\em a priori} methodology, we
find results in good agreement with available experimental reaction barriers.
We then study, in a controlled manner, the relative importance of various
further approximations that are routinely performed in the literature such as
the use of spherical cavities, the replacement of the reactant by a dipole, or
the neglect of self consistency in solving the electrostatic problem.

</DOC>
<DOC>
<DOCNO> 122497 </DOCNO>
An Extinction Map and Color Magnitude Diagram for the Globular Cluster


  Differential $E_{V-I}$ variations of up to $\sim 0.2$ mag on a scale of
arcminutes across NGC 3201 are presented in the form of an extinction map. This
map, created by calculating average $E_{V-I}$ values for stars in small
subregions of the field with respect to a fiducial region, greatly improves the
appearance of the CMD of the cluster. We describe how we implemented this
technique in detail with our data for NGC 3201. A comparison between our map
and that of the same region extracted from the COBE/DIRBE reddening maps
published by Schlegel, Finkbeiner, & Davis (1998) (SFD) displays larger-scale
similarities between the two maps as well as smaller-scale features which show
up in our map but not in the SFD map. Several methods of determining an
$E_{V-I}$ zeropoint to add to our differential extinction map are presented.
Isochrone fitting proved to be the most successful one, but it produces an
average $E_{V-I}$ for the cluster which is smaller than previously published
values by $\sim 1.5\sigma$. Finally, our results seem to support the statement
by Arce & Goodman (1999) that the SFD maps overestimate the reddening in
regions of high extinction.

</DOC>
<DOC>
<DOCNO> 102421 </DOCNO>
On the String-Theoretic Euler Number of a Class of Absolutely Isolated


  An explicit computation of the so-called string-theoretic E-function of a
normal complex variety X with at most log-terminal singularities can be
achieved by constructing one snc-desingularization of X, accompanied with the
intersection graph of the exceptional prime divisors, and with the precise
knowledge of their structure. In the present paper, it is shown that this is
feasible for the case in which X is the underlying space of a class of
absolutely isolated singularities (including both usual A_{n}-singularities and
Fermat singularities of arbitrary dimension). As byproduct of the exact
evaluation of e_{str}(X), for this class of singularities, one gets (in
contrast to the expectations of V1!) counterexamples to a conjecture of Batyrev
concerning the boundedness of the string-theoretic index. Finally, the
string-theoretic Euler number is also computed for global complete
intersections in P^{N} with prescribed singularities of the above type.

</DOC>
<DOC>
<DOCNO> 118520 </DOCNO>
Where Do We Stand?


  I review the understanding of bulges that emerged from the lively discussions
and presentations during the meeting, and emphasize areas for future work. The
evidence is for a diversity of `bulges', and of formation mechanisms.

</DOC>
<DOC>
<DOCNO> 14059 </DOCNO>
A generalization of Clausius inequality for processes between


  We investigate nonequilibrium chemical reaction systems from the view point
of steady state thermodynamics proposed by Oono and Paniconi [Prog. Theor.
Phys. Suppl. 130, 29 (1998)]. The concentrations of some compounds are operated
by an external system, so that a transition from a steady state to other steady
state takes place. We show that an analogue of Clausius inequality holds
macroscopically for the operation processes. This implies that the second law
of thermodynamics can be generalized, including nonequilibrium steady states.

</DOC>
<DOC>
<DOCNO> 119199 </DOCNO>
Homogeneous Photometry for Star Clusters and Resolved Galaxies. II.


  Stars appearing in CCD images obtained over 224 nights during the course of
69 observing runs have been calibrated to the Johnson/Kron-Cousins BVRI
photometric system defined by the equatorial standards of Landolt (1992, AJ,
104, 340). More than 15,000 stars suitable for use as photometric standards
have been identified, where "suitable" means that the star has been observed
five or more times during photometric conditions and has a standard error of
the mean magnitude less than 0.02 mag in at least two of the four bandpasses,
and shows no significant evidence of intrinsic variability. Many of these stars
are in the same fields as Landolt's equatorial standards or Graham's (1982,
PASP, 94, 244) southern E-region standards, but are considerably fainter. This
enhances the value of those fields for the calibration of photometry obtained
with large telescopes. Other standards have been defined in fields containing
popular objects of astrophysical interest, such as star clusters and famous
galaxies, extending Landolt-system calibrators to declinations far from the
equator and to stars of sub-Solar chemical abundances. I intend to continue to
improve and enlarge this set of photometric standard stars as more observing
runs are reduced. The full current database of photometric indices is being
made freely available via a site on the World-Wide Web, or by direct request to
the author. Although the contents of the database will evolve in detail, at any
given time it should represent the largest sample of precise BVRI broad-band
photometric standards available anywhere.

</DOC>
<DOC>
<DOCNO> 120333 </DOCNO>
The ASCA HSS: Looking for Type 2 AGN


  We will briefly discuss the X-ray spectral properties of the objects in the
ASCA Hard Serendipitous Survey (HSS) sample and its present AGN contents. We
also present X-ray spectroscopy of two Type 2 AGN belonging to the sample.

</DOC>
<DOC>
<DOCNO> 8505 </DOCNO>
Temporal correlations versus noise in the correlation matrix formalism:


  We adopt the concept of the correlation matrix to study correlations among
sequences of time-extended events occuring repeatedly at consecutive
time-intervals. As an application we analyse the magnetoencephalography
recordings obtained from human auditory cortex in epoch mode during delivery of
sound stimuli to the left or right ear. We look into statistical properties and
the eigenvalue spectrum of the correlation matrix C calculated for signals
corresponding to different trials and originating from the same or opposite
hemispheres. The spectrum of C largely agrees with the universal properties of
the Gaussian orthogonal ensemble of random matrices, with deviations
characterised by eigenvectors with high eigenvalues. The properties of these
eigenvectors and eigenvalues provide an elegant and powerful way of quantifying
the degree of the underlying collectivity during well defined latency intervals
with respect to stimulus onset. We also extend this analysis to study the
time-lagged interhemispheric correlations, as a computationally less demanding
alternative to other methods such as mutual information.

</DOC>
<DOC>
<DOCNO> 13913 </DOCNO>
Radiation attenuation of bend oscillations of coherent martensitic and


  In frameworks of the macroscopic dynamic theory of coherent interfaces in
crystals the acoustic radiation of coherent boundary at passage along it of
localized wave packages is considered. It is shown that the coherent twin
boundary of acoustic waves does not radiate.

</DOC>
<DOC>
<DOCNO> 118872 </DOCNO>
The evolution of rotating stars


  First, we review the main physical effects to be considered in the building
of evolutionary models of rotating stars on the Upper Main-Sequence (MS). The
internal rotation law evolves as a result of contraction and expansion,
meridional circulation, diffusion processes and mass loss. In turn,
differential rotation and mixing exert a feedback on circulation and diffusion,
so that a consistent treatment is necessary.
  We review recent results on the evolution of internal rotation and the
surface rotational velocities for stars on the Upper MS, for red giants,
supergiants and W-R stars. A fast rotation is enhancing the mass loss by
stellar winds and reciprocally high mass loss is removing a lot of angular
momentum. The problem of the ``break-up'' or $\Omega$-limit is critically
examined in connection with the origin of Be and LBV stars. The effects of
rotation on the tracks in the HR diagram, the lifetimes, the isochrones, the
blue to red supergiant ratios, the formation of W-R stars, the chemical
abundances in massive stars as well as in red giants and AGB stars, are
reviewed in relation to recent observations for stars in the Galaxy and
Magellanic Clouds. The effects of rotation on the final stages and on the
chemical yields are examined, as well as the constraints placed by the periods
of pulsars. On the whole, this review points out that stellar evolution is not
only a function of mass M and metallicity Z, but of angular velocity $\Omega$
as well.

</DOC>
<DOC>
<DOCNO> 120839 </DOCNO>
RXTE observations of XTE J2012+381 during its 1998 outburst


  We present an analysis of the RXTE observations of X-ray transient source XTE
J2012+381 during its 1998 outburst. The spectral and timing properties of the
source emission and their evolution during the outburst are very similar to
what of the X-ray Novae.

</DOC>
<DOC>
<DOCNO> 9674 </DOCNO>
Quasiparticle spectrum in the vortex state of d-wave superconductors


  Quasiparticle spectrum associated with the nodal structure in d-wave
superconductors is of great interest. We study theoretically the quasi-particle
spectrum in a planar magnetic field, where the effect of the magnetic field is
treated in terms of the Doppler shift. We obtain the angular dependent specific
heat in the presence of a planar magnetic field and impurities, both in the
superclean limit (Gamma/Delta << H/H_{c2}<< 1) and in the clean limit (H/H_{c2}
<< Gamma/Delta <<1). Also a similar analysis is used for the thermal
conductivity tensor within the a-b plane. In particular, in contrast to the
earlier works, we find a fourfold symmetry term in \kappa_{\parallel} and
\kappa_{\perp} \sim -H \sin(2\theta) where kappa_{perp} are the diagonal- and
the off-diagonal components of the thermal conductivity tensor and \theta is
the angle between the heat current and the magnetic field.

</DOC>
<DOC>
<DOCNO> 120320 </DOCNO>
A test of arm induced star formation in spiral galaxies from near-IR and


  We have imaged a sample of 20 face-on spiral galaxies in H\alpha and in the
near-IR K-band (2.2 microns), in order to determine the location and strength
of star formation with respect to perturbations in the old stellar population.
We found that star formation rates are significantly enhanced near K-band arms.
If K-band light is dominated by emission from old stars, this shows that
density waves trigger star formation. However, no significant correlation was
found between the global underlying disk properties of spiral galaxies and
their total star formation rates.

</DOC>
<DOC>
<DOCNO> 8463 </DOCNO>
Non-equlibrium effects in transport through quantum dots


  The role of non-equilibrium effects in the conductance through quantum dots
is investigated. Associated with single-electron tunneling are shake-up
processes and the formation of excitonic-like resonances. They change
qualitatively the low temperature properties of the system. We analyze by
quantum Monte Carlo methods the renormalization of the effective capacitance
and the gate-voltage dependent conductance. Experimental relevance is
discussed.

</DOC>
<DOC>
<DOCNO> 13788 </DOCNO>
CDW, Superconductivity and Anomalous Metallic Behavior in 2D Transition


  We propose a theory for quasi-two-dimensional transition metal
dichalcogenides that provides a unified microscopic picture of the charge
density wave (CDW) and superconducting phases. We show, based on the
electron-phonon coupling and Fermi surface topology, that a CDW order parameter
with six-fold symmetry and nodes (f-wave) gives a consistent description of the
available experimental data. The elementary excitations in the CDW phase are
Dirac electrons. The superconducting state has its origin on the attractive
interaction mediated by phonons. The theory predicts strong deviations from
Fermi liquid theory in the CDW phase.

</DOC>
<DOC>
<DOCNO> 10740 </DOCNO>
Time-dependent Gutzwiller approximation for the Hubbard model


  We develop a time-dependent Gutzwiller approximation (GA) for the Hubbard
model analogous to the time-dependent Hartree-Fock (HF) method. The formalism
incorporates ground state correlations of the random phase approximation (RPA)
type beyond the GA. Static quantities like ground state energy and double
occupancy are in excellent agreement with exact results in one dimension up to
moderate coupling and in two dimensions for all couplings. We find a
substantial improvement over traditional GA and HF+RPA treatments. Dynamical
correlation functions can be easily computed and are also substantially better
than HF+RPA ones and obey well behaved sum rules.

</DOC>
<DOC>
<DOCNO> 101402 </DOCNO>
Complex numbers in 5 dimensions


  A system of commutative complex numbers in 5 dimensions of the form
u=x_0+h_1x_1+h_2x_2+h_3x_3+h_4x_4 is described in this paper, the variables
x_0, x_1, x_2, x_3, x_4 being real numbers. The operations of addition and
multiplication of the 5-complex numbers introduced in this work have a
geometric interpretation based on the the modulus d, the amplitude \rho, the
polar angle \theta_+, the planar angle \psi_1, and the azimuthal angles
\phi_1,\phi_2. The exponential function of a 5-complex number can be expanded
in terms of polar 5-dimensional cosexponential functions g_{5k}(y),
k=0,1,2,3,4, and the expressions of these functions are obtained from the
properties of the exponential function of a 5-complex variable. Exponential and
trigonometric forms are obtained for the 5-complex numbers, which depend on the
modulus, the amplitude and the angular variables. The 5-complex functions
defined by series of powers are analytic, and the partial derivatives of the
components of the 5-complex functions are closely related. The integrals of
5-complex functions are independent of path in regions where the functions are
regular. The fact that the exponential form of the 5-complex numbers depends on
the cyclic variables \phi_1, \phi_2 leads to the concept of pole and residue
for integrals on closed paths. The polynomials of 5-complex variables can be
written as products of linear or quadratic factors.

</DOC>
<DOC>
<DOCNO> 123312 </DOCNO>
Classification of Light curves of the Black Hole Candidate GRS1915+105


  The black hole candidate GRS 1915+105 exhibits a rich variety of variability.
Assuming that the earlier paradigm of black hole accretion which includes a
shock is applicable for this system as well, one can classify these
variabilities into four classes. We present light curves of these classes and
discuss the basis of our classification.

</DOC>
<DOC>
<DOCNO> 152602 </DOCNO>
Open N=2 strings in a B-field background and noncommutative self-dual


  In the presence of D-branes, fermionic N=2 strings in 2+2 dimensions can be
coupled to a K"ahler NS-NS two-form B. We present the corresponding action
which produces N=2 supersymmetric boundary conditions and discuss the
Seiberg-Witten zero-slope limit. After recalling the constraints on the
Chan-Paton gauge group, we demonstrate for U(n) groups that the open N=2 string
with a nonzero B-field coincides on tree level with noncommutative self-dual
Yang-Mills. Several misconceptions of hep-th/0011206 are corrected.

</DOC>
<DOC>
<DOCNO> 99701 </DOCNO>
Description de la structure de certaines superalg\`ebres de Lie


  In this note we introduce the notion of $T^*-$extension $T^*{\mathfrak g}$ of
a Lie superalgebra ${\mathfrak g}$, i.e. an extension of ${\mathfrak g}$ by its
dual space ${\mathfrak g}^*$. The natural pairing induces on $T^*{\mathfrak g}$
an even supersymmetric nondegenerate bilinear form $B$ which is invariant
($B([X,Y],Z)=B(X,[Y,Z])$ for all $X,Y,Z \in T^*{\mathfrak g}$), i.e. the
structure of a quadratic (or metrised or orthogonal) Lie superalgebra. These
extensions can be classified by the third even scalar cohomology group of
${\mathfrak g}$. Moreover, we show that all finite-dimensional quadratic Lie
superalgebras ${\mathfrak a}={\mathfrak a}_{\bar{0}} \oplus {\mathfrak
a}_{\bar{1}}$ which are either nilpotent, or solvable and such that
$[{\mathfrak a}_{\bar{1}},{\mathfrak a}_{\bar{1}}]\subset [{\mathfrak
a}_{\bar{0}},{\mathfrak a}_{\bar{0}}]$ can be constructed by means of a
$T^*-$extension in the case of an algebraically closed field of characteristic
zero.

</DOC>
<DOC>
<DOCNO> 100302 </DOCNO>
On perfectly meager sets


  A set of reals A is called perfectly meager if A \cap P is meager in P, for
every perfect set P. Marczewski asked if the product of perfectly meager sets
is perfectly meager. In the paper it is shown that it is consistent that the
answer to this question is positive. (It is known that it is also consistent
that the answer is negative (Reclaw))

</DOC>
<DOC>
<DOCNO> 8626 </DOCNO>
Quantum Phase Transition in Extended Attractive Hubbard Model


  We have made a variational analysis on an evolution of superconductivity from
weak to strong coupling regime. In contrast to a crossover without
thermodynamic anomaly found in a dilute system, we show the existence of a
quantum phase transition near half filling. The transition is driven by charge
density waves instabilities. We have found that superconductivity and charge
density waves coexist in the presence of a weak intersite repulsion. The ground
state phase diagram is determined and the quantum phase transition is an
attractive version of the Mott transition.

</DOC>
<DOC>
<DOCNO> 120609 </DOCNO>
The star formation history of resolved galaxies: Composite H-R diagram


  I discuss the information provided by color-magnitude diagrams of different
absolute magnitude limits in the study of the star formation histories of
nearby galaxies. I review the recent progress made in the field, with emphasis
on the results for Local Group dwarf galaxies.

</DOC>
<DOC>
<DOCNO> 7808 </DOCNO>
The single electron R-pump: first experiment


  We fabricated and tested the single electron R-pump, i.e. a three-junction Al
circuit with on-chip Cr resistors. We show that due to the presence of the
resistors (R > h/e^2 = 25.8 kOhm), the accuracy of electron transfer in the
R-pump can approach the level of 10^-8. Preliminary results of experiment with
the R-pump made at PTB are reported.

</DOC>
<DOC>
<DOCNO> 122895 </DOCNO>
Correlations of Cosmic Tidal Fields


  We study correlations amongst tidal fields originated by the large-scale
distribution of matter in the Universe. The two-point tidal correlation is
described as a rank-4 tensor, whose elements can be written in terms of four
fundamental scalar functions ranging, with respect the spatial separation, from
purely transversal to purely longitudinal correlations. Tidal fields, both on
galaxy and cluster scales, reveal to be correlated over distances larger than
the mass-density correlation lenght, though traceless tidal fields show
anti-correlation between diagonal terms along orthogonal directions. The
cross-correlation between mass and tidal field is also analyzed. These results
are relevant for galaxy formation and the interpretation of large-scale weak
lensing phenomena.

</DOC>
<DOC>
<DOCNO> 170419 </DOCNO>
Space-bounded computation: quantum is better than classical


  This paper has been withdrawn, as all conjectures (and one claim) have been
proven incorrect. Some of what remains may eventually reappear in a different
context.

</DOC>
<DOC>
<DOCNO> 14002 </DOCNO>
Resonant Inelastic X-ray Scattering from Charge and Orbital Excitations


  We present a theory of the resonant inelastic x-ray scattering (RIXS) to
study electronic excitations in orbital ordered manganites. The charge and
orbital excitations of the Mn 3d electron are caused by the Coulomb
interactions in the intermediate scattering state. The scattering cross section
is formulated by the Liouville operator method where the local and itinerant
natures of the excitations are taken into account on an equal footing. As a
result, the cross section is expressed by the charge and orbital correlation
functions associated with local corrections. The RIXS spectra are calculated
numerically as functions of momentum and polarization of x ray. Through the
calculations, we propose that RIXS provides a great opportunity to study the
unique electronic excitations in correlated electron systems with orbital
degeneracy.

</DOC>
<DOC>
<DOCNO> 68502 </DOCNO>
New and Standard Physics contributions to anomalous Z and gamma


  We examine the Standard and the New Physics (NP) contributions to the ZZZ,
ZZgamma and Zgammagamma neutral gauge couplings. At the one-loop level, if we
assume that there is no CP violation contained in NP beyond the Standard Model
one, we find that only CP conserving neutral gauge couplings are generated,
either from the standard quarks and leptons, or from possible New Physics (NP)
fermions. Bosonic one-loop diagrams never contribute to these couplings, while
the aforementioned fermionic contributions satisfy hZ3=-fgamma5, hZ4=hgamma4=0.
We also study examples of two-loop NP effects that could generate non vanishing
h4 couplings. We compare quantitative estimates from SM, MSSM and some specific
examples of NP contributions, and we discuss their observability at future
colliders.

</DOC>
<DOC>
<DOCNO> 40398 </DOCNO>
Investigation of single spin asymmetries in pi^{+} electroproduction


  The azimuthal single target-spin asymmetries for pi^{+} production in
semi-inclusive deep inelastic scattering of leptons off longitudinally
polarized protons are evaluated using two main approaches available in the
literature. It is shown that the approximation where the twist-2 transverse
quark spin distribution in the longitudinally polarized nucleon is small enough
to be neglected leads to a consistent description of all existing asymmetries
observed by the HERMES experiment.

</DOC>
<DOC>
<DOCNO> 71769 </DOCNO>
Fermion families, and chirality through extra dimensions


  We give a simple model to explain the origin of fermion families, and
chirality through the use of a domain wall placed in a five dimensional
space-time.

</DOC>
<DOC>
<DOCNO> 67952 </DOCNO>
Approaching the parameter estimation quality of maximum likelihood via


  A simple criterion is presented for a practical construction of generalized
moments that allow one to approach the theoretical Rao-Cramer limit for
parameter estimation while avoiding the complexity of the maximum likelihood
method in the cases of complicated probability distributions and/or very large
event samples.

</DOC>
<DOC>
<DOCNO> 71948 </DOCNO>
On possible $\Theta$ vacua states in heavy ion collisions


  We have simulated the possible $\Theta$ vacua states in heavy ion collisions.
In a quench like scenario, random phases of the chiral fields were evolved in a
zero temperature potential incorporating the breaking of $U_A(1)$ symmetry.
Initial random phases very quickly settles into oscillation around the values
dictated by the potential. The simulation indicate that $\Theta$ vacua states
that can be populated in heavy ion collisions is a coherent superposition of a
number of modes.

</DOC>
<DOC>
<DOCNO> 118545 </DOCNO>
Reionization Constraints on the Contribution of Primordial Compact


  Many lines of evidence suggest that nonbaryonic dark matter constitutes
roughly 30% of the critical closure density, but the composition of this dark
matter is unknown. One class of candidates for the dark matter is compact
objects formed in the early universe, with typical masses M between 0.1 and 1
solar masses to correspond to the mass scale of objects found with microlensing
observing projects. Specific candidates of this type include black holes formed
at the epoch of the QCD phase transition, quark stars, and boson stars. Here we
show that accretion onto these objects produces substantial ionization in the
early universe, with an optical depth to Thomson scattering out to z=1100 of
approximately tau=2-4 [f_CO\epsilon_{-1}(M/Msun)]^{1/2} (H_0/65)^{-1}, where
\epsilon_{-1} is the accretion efficiency \epsilon\equiv L/{\dot M}c^2 divided
by 0.1 and f_CO is the fraction of matter in the compact objects. The current
upper limit to the scattering optical depth, based on the anisotropy of the
microwave background, is approximately 0.4. Therefore, if accretion onto these
objects is relatively efficient, they cannot be the main component of
nonbaryonic dark matter.

</DOC>
<DOC>
<DOCNO> 123026 </DOCNO>
Luminosity function of clusters of galaxies


  The composite galaxy luminosity function (hereafter LF) of 39 Abell clusters
of galaxies is derived by computing the statistical excess of galaxy counts in
the cluster direction with respect to control fields. Due to the wide field
coverage of the digitised POSS-II plates, we can measure field counts around
each cluster in a fully homogeneous way. Furthermore, the availability of
virtually unlimited sky coverage allows us to directly compute the LF errors
without having to rely on the estimated variance of the background. The wide
field coverage also allows us to derive the LF of the whole cluster, including
galaxies located in the cluster outskirts. The global composite LF has a slope
alpha ~ -1.1+/-0.2 with minor variations from blue to red filters, and M* ~
-21.7,-22.2,-22.4 mag (H_0=50 km/s/Mpc) in g, r and i filters, respectively.
These results are in quite good agreement with several previous determinations
and in particular with the LF determined for the inner region of a largely
overlapping set of clusters, but derived making use of a completely different
method for background subtraction. The similarity of the two LFs suggests the
existence of minor differences between the LF in the cluster outskirts and in
the central region, or a negligible contribution of galaxies in the cluster
outskirts to the global LF.

</DOC>
<DOC>
<DOCNO> 13350 </DOCNO>
First integrals of Ginzburg-Landau equations and stability criteria for


  The first integrals of the Ginzburg-Landau equations for a vortex-free state
of superconductors with different mixed symmetries of the order parameter are
found. The general boundary conditions for the order parameter at the ideal
interface between the superconductor and vacuum are derived. Based on these
integrals and boundary conditions, we analyze the stability criteria for
vortex-free state in unconventional superconductors. The threshold field above
which the Abrikosov vortices can enter the superconductor is found to be higher
or equal to the thermodynamic critical field for all states under study.

</DOC>
<DOC>
<DOCNO> 169572 </DOCNO>
Inequalities for dealing with detector inefficiencies in


  In this article we show that the three-particle GHZ theorem can be
reformulated in terms of inequalities, allowing imperfect correlations due to
detector inefficiencies. We show quantitatively that taking into accout those
inefficiencies, the published results of the Innsbruck experiment support the
nonexistence of local hidden variables that explain the experimental result.

</DOC>
<DOC>
<DOCNO> 117027 </DOCNO>
Status of the RFD Linac Structure Developement


  The Proof-of-Principle (POP) prototype of the Rf-Focused Drift tube (RFD)
linac structure is currently under test at Linac Systems, after years of delay
due to a variety of technical problems. A discussion of these technical
problems and their solutions will be presented. The status of these tests will
be reported. Plans for future development of this linac structure will be
revealed. Potential uses of this linac structure for a variety of scientific,
medical, and industrial applications will be described, including: proton linac
injectors for proton synchrotrons, compact proton linacs for PET isotope
production, epithermal neutron sources for the BNCT application, energy
boosters for proton therapy, compact portable neutron sources for thermal
neutron radiography, and pulsed cold neutron sources for cold neutron physics
and related applications.

</DOC>
<DOC>
<DOCNO> 84397 </DOCNO>
The geometry of the Barbour-Bertotti theories I. The reduction process


  The dynamics of $N\geq 3$ interacting particles is investigated in the
non-relativistic context of the Barbour-Bertotti theories. The reduction
process on this constrained system yields a Lagrangian in the form of a
Riemannian line element. The involved metric, degenerate in the flat
configuration space, is the first fundamental form of the space of orbits of
translations and rotations (the Leibniz group). The Riemann tensor and the
scalar curvature are computed by a generalized Gauss formula in terms of the
vorticity tensors of generators of the rotations. The curvature scalar is
further given in terms of the principal moments of inertia of the system. Line
configurations are singular for $N\neq 3$. A comparison with similar methods in
molecular dynamics is traced.

</DOC>
<DOC>
<DOCNO> 100574 </DOCNO>
Calculus of clovers and finite type invariants of 3-manifolds


  A clover is a framed trivalent graph with some additional structure, embedded
in a 3-manifold. We define surgery on clovers, generalizing surgery on Y-graphs
used earlier by the second author to define a new theory of finite-type
invariants of 3--manifolds. We give a systematic exposition of a topological
calculus of clovers and use it to deduce some important results about the
corresponding theory of finite type invariants. In particular, we give a
description of the weight systems in terms of uni-trivalent graphs modulo the
AS and IHX relations, reminiscent of the similar results for links. We then
compare several definitions of finite type invariants of homology spheres
(based on surgery on Y--graphs, blinks, algebraically split links, and boundary
links) and prove in a self-contained way their equivalence.

</DOC>
<DOC>
<DOCNO> 69513 </DOCNO>
One-Loop Factorization of the Nucleon g_2-Structure Function in the


  We consider the one-loop factorization of the simplest twist-three process:
inclusive deep-inelastic scattering of longitudinally-polarized leptons on a
transversely-polarized nucleon target. By studying the Compton amplitudes for
certain quark and gluon states at one loop, we find the coefficient functions
for the non-singlet twist-three distributions in the factorization formula of
g_2(x_B,Q^2). The result marks the first step towards a next-to-leading order
(NLO) formalism for this transverse-spin-dependent structure function of the
nucleon.

</DOC>
<DOC>
<DOCNO> 118474 </DOCNO>
The Role of Heating and Enrichment in Galaxy Formation


  We show that the winds identified with high-redshift low-mass galaxies may
strongly affect the formation of stars in more massive galaxies that form
later. With 3D realizations of a simple linear growth model we track gas
shocking, metal enrichment, and cooling, together with dark halo formation. We
show that outflows typically strip baryonic material out of collapsing
intermediate mass halos, suppressing star formation. More massive halos can
trap the heated gas but collapse late, leading to a broad bimodal redshift
distribution, with a larger characteristic mass associated with the lower
redshift peak. This scenario accounts for the observed bell-shaped luminosity
function of early type galaxies, explains the small number of Milky Way
satellite galaxies relative to Cold Dark Matter models predictions, and
provides a possible explanation for the lack of metal poor G-dwarfs in the
solar neighborhood and the more general lack of low-metallicity stars in
massive galaxies relative to ``closed-box'' models of chemical enrichment.
Intergalactic medium heating from outflows should produce spectral distortions
in the cosmic microwave background that will be measurable with the next
generation of experiments.

</DOC>
<DOC>
<DOCNO> 67984 </DOCNO>
Re-Evaluation of the Elastic Scattering of Supersymmetric Dark Matter


  We examine the cross sections for the elastic scattering of neutralinos
$\chi$ on nucleons $p,n$, as functions of $m_\chi$ in the constrained minimal
supersymmetric standard model. We find narrow bands of possible values of the
cross section, that are considerably lower than some previous estimates. The
constrained model is based on the minimal supergravity-inspired framework for
the MSSM, with universal scalar and gaugino masses $m_0, m_{1/2}$, and $\mu$
and the MSSM Higgs masses treated as dependent parameters. We explore
systematically the region of the $(m_{1/2}, m_0)$ plane where LEP and other
accelerator constraints are respected, and the relic neutralino density lies in
the range $0.1 \le \Omega_{\chi} h^2 \le 0.3$ preferred by cosmology. We update
previous discussions of both the spin-independent and -dependent scattering
matrix elements on protons and neutrons, using recent analyses of low-energy
hadron experiments.

</DOC>
<DOC>
<DOCNO> 122514 </DOCNO>
Detecting X-ray Synchrotron Emission in Supernova Remnants: Implications


  The 10^51 ergs released in a supernova have far reaching consequences in the
galaxy, determining elemental abundances, accelerating cosmic rays, and
affecting the makeup of the interstellar medium. Recently the spectra of
several supernova remnants have been found to be dominated by nonthermal
emission. Separating the thermal and nonthermal components is important not
only for the understanding of cosmic-ray acceleration and shock microphysics
properties but for accurate assessment of the temperatures and line strengths.
New models designed to model spatially resolved synchrotron X-rays from type Ia
supernovae can contribute to the understanding of both the thermal physics
(dynamics, abundances) and nonthermal physics (shock acceleration,
magnetic-field amplification) of supernova remnants. I will describe model fits
to SN 1006, emphasizing the physical constraints that can be placed on SNRs,
abundances, and the cosmic-ray acceleration process.

</DOC>
<DOC>
<DOCNO> 117616 </DOCNO>
Weak Lensing of the CMB: A Harmonic Approach


  Weak lensing of CMB anisotropies and polarization for the power spectra and
higher order statistics can be handled directly in harmonic-space without
recourse to real-space correlation functions. For the power spectra, this
approach not only simplifies the calculations but is also readily generalized
from the usual flat-sky approximation to the exact all-sky form by replacing
Fourier harmonics with spherical harmonics. Counterintuitively, due to the
nonlinear nature of the effect, errors in the flat-sky approximation do not
improve on smaller scales. They remain at the 10% level through the acoustic
regime and are sufficiently large to merit adoption of the all-sky formalism.
For the bispectra, a cosmic variance limited detection of the correlation with
secondary anisotropies has an order of magnitude greater signal-to-noise for
combinations involving magnetic parity polarization than those involving the
temperature alone. Detection of these bispectra will however be severely noise
and foreground limited even with the Planck satellite, leaving room for
improvement with higher sensitivity experiments. We also provide a general
study of the correspondence between flat and all sky potentials, deflection
angles, convergence and shear for the power spectra and bispectra.

</DOC>
<DOC>
<DOCNO> 101997 </DOCNO>
Useful branched surfaces which carry nothing


  In this paper we give a positive answer to the question "are there useful
branched surfaces which carry nothing?" Conversely, we point out the subtlety
of the question "when does a branched surface in a 3-manifold fully carry a
lamination?" by constructing for every n a 3-manifold and a branched surface
whose lift to a certain degree n cover fully carries an essential lamination,
but whose lift to any degree m cover with m<n does not carry anything. These
two questions were both posed by D. Gabai in his well-known problem list.
  These branched surfaces are dual to certain combinatorial structures called
"taut local orientations" (introduced in math.GT/9803109) which have smooth
analogues called "taut cone fields"; these objects are a more flexible
generalization of a taut foliation, and are not subject to the Milnor-Wood
inequality.
  Certain kinds of taut local orientations are also related to 1-cochains with
bounded coboundary which satisfy a certain geometric condition of being
"uniform". A 3-manifold admitting a uniform 1-cochain is a more flexible
generalization of a 3-manifold which slithers over the circle; we show that
such 3-manifolds satisfy the weak geometrization conjecture - that is, their
fundamental groups contain a free abelian group of rank two or are
word-hyperbolic.

</DOC>
<DOC>
<DOCNO> 71629 </DOCNO>
A simple solution to color confinement


  We show that color confinement is a direct result of the nonabelian, i.e.
nonlinear, nature of the color interaction in quantum chromodynamics. This
makes it in general impossible to describe the color field as a collection of
elementary quanta (gluons). A quark cannot be an elementary quanta of the quark
field, as the color field of which it is the source is itself a source hence
making isolated (noninteracting) quarks impossible. In geometrical language,
the impossibility of quarks and gluons as physical particles arises due to the
fact that the color Yang-Mills space does not have a constant trivial
curvature.

</DOC>
<DOC>
<DOCNO> 84674 </DOCNO>
Brane Universe and Standard Cosmology


  Brane cosmology takes the unconventional form $H\sim \sqrt{\rho}$. To recover
the standard cosmology, we have to assume that the matter density is much less
than the brane tension. We show that the assumption can be justified even near
the end of inflation if we fine-tune the coupling constant of the inflaton
potential. As a consequence, the standard cosmology is recovered after
inflation.

</DOC>
<DOC>
<DOCNO> 122860 </DOCNO>
Astrophysical tests for the Novello-De Lorenci-Luciane theory of


  The Novello-DeLorenci-Luciane (NDL) field theory of gravitation predicts that
gravitational waves (GWs) follow geodesics of a modified (effective) geometry
with a speed lower than the velocity of light. The theory also demonstrates
that GWs exhibit the phenomenon of birefringence, formerly believed to be
exclusive of electromagnetic waves. Here prospective astrophysical tests of
these predictions are proposed. I point out that future measurements of
gravitational waves in coincidence with a non-gravitational process such as
{\it a neutrino burst} (and likely a burst of gamma-rays) may prove useful to
discriminate among all the existing theories of gravity. It is also stressed
that microlensing of gravitational waves emitted by known galactic sources
(i.e., pulsars) in the bulge, lensed by either the Galaxy's central black hole
(Sgr A$^\ast$) or a MACHO object adrift among the Milky Way's stars, may
provide a clean test of the birefringence phenomenon implied by the NDL gravity
theory.

</DOC>
<DOC>
<DOCNO> 84914 </DOCNO>
Emergent Consciousness: From the Early Universe to Our Mind


  In a previous paper (gr-qc/9907063) we described the early inflationary
universe in terms of quantum information. In this paper, we analize those
results in more detail, and we stress the fact that, during inflation, the
universe can be described as a superposed state of quantum registers. The
self-reduction of the superposed quantum state is consistent with the Penrose's
Objective Reduction (OR) model. The quantum gravity threshold is reached at the
end of inflation, and corresponds to a superposed state of 10^9 quantum
registers. This is also the number of superposed tubulins-qubits in our brain,
which undergo the Penrose-Hameroff's Orchestrated Objective Reduction, (Orch
OR), leading to a conscious event. Then, an analogy naturally arises between
the very early quantum computing universe,and our mind.

</DOC>
<DOC>
<DOCNO> 116941 </DOCNO>
Design of the 7 MeV/u, 217 MHz Injector Linac for the Proposed Ion Beam


  A dedicated clinical synchrotron facility for cancer therapy using energetic
proton and ion beams (C, He and O) has been designed at GSI for the
Radiologische Universitaetsklinik at Heidelberg, Germany. The design of the
injector linac is presented. Suitable ion sources are discussed and results of
ion source test measurements are reported. The LEBT allows for switching
between two ion sources. A short RFQ accelerates the ions from 8 keV/u to 400
keV/u. It is followed by a very compact beam matching section and a 3.8 m long
IH-type drift tube linac for the acceleration to 7 MeV/u. Both rf structures
are designed for a resonance frequency of 216.816 MHz and for ion
mass-to-charge ratios up to A/q = 3 (12C4+, (H_3)+, 3He+, 16O6+).

</DOC>
<DOC>
<DOCNO> 10003 </DOCNO>
Mechanism of confinement in low-dimensional organic conductors


  Confinement-deconfinement transition in quarter-filled two-coupled chains
comprising dimerization, repulsive interactions and interchain hopping has been
demonstrated by applying the renormalization group method to the bosonized
Hamiltonian. The confinement given by the irrelevant interchain hopping occurs
with increasing umklapp scattering which is induced by the dimerization leading
to effectively half-filling. It is shown that the transition originates in a
competition between a charge gap and the renormalized interchain hopping.

</DOC>
<DOC>
<DOCNO> 122329 </DOCNO>
A Giant Bipolar Shell around the WO star in the Galaxy IC 1613:


  Observations of the nebula associated with the WO star in the galaxy IC 1613
are presented. The observations were carried out with a scanning Interferometer
Fabry-Perot in H_alpha at the 6m Special Astrophysical Observatory telescope;
narrow-band H_alpha and [OIII] images were obtained with the 4-m KPNO
telescope. The monochromatic H_alpha image clearly reveals a giant bipolar
shell structure outside the bright nebula S3. The sizes of the southeastern and
northwestern shells are 112x77 pc and (186-192)x(214-224) pc, respectively. We
have studied the object's kinematics for the first time and found evidence for
expansion of both shells. The expansion velocities of the southeastern and
northwestern shells exceed 50 and 70 km/s, respectively. We revealed a
filamentary structure of the shells and several compact features in the S3
core. A scenario is proposed for the formation of the giant bipolar structure
by the stellar wind from the central WO star located at the boundary of a dense
``supercavity'' in the galaxy's H I distribution.

</DOC>
<DOC>
<DOCNO> 40274 </DOCNO>
Using Thin Film Targets for Muonic Atoms and Muon Catalyzed Fusion


  Studies of muonic atoms and muon catalyzed fusion have been conventionally
done in a bulk target of gas, liquid or solid hydrogen isotopes. The use of
thin film targets developed at TRIUMF have notable advantages in tackling some
of the most important questions in the field, which could be further exploited
at future high intensity muon sources. We review the technique of the thin film
method with emphasis on recent results and a future proposal.

</DOC>
<DOC>
<DOCNO> 13841 </DOCNO>
Optical conductivity of d-wave superconductors


  We study theoretically the optical conductivity of d-wave superconductors
like in high temperature cuprates in the presence of impurities. We limit
ourselves at T=0K and focus on the frequency dependence of both sigma_1(omega)
and \omega*\sigma_2(omega) for omega<2Delta. When the impurity scattering is in
the unitary limit, we find a peak in sigma_1(omega) with omega/Delta\simeq
0.1\sim 0.5$, which may account for the peak seen by Basov et al. in
Zn-substituted YBCO.

</DOC>
<DOC>
<DOCNO> 122427 </DOCNO>
Detection of X-ray line emission from the shell of SNR B0540-69.3 with


  We present X-ray observations of PSR 0540-69.3 with the XMM-Newton
observatory. The spectra obtained with the Reflection Grating Spectrometer
reveal, for the first time, emission from ionized species of O, Ne and Fe
originating from the SNR shell. Analysis of the emission line spectrum allows
us to derive estimates of the temperature, ionization timescale, abundances,
location, and velocity of the emitting gas.

</DOC>
<DOC>
<DOCNO> 13202 </DOCNO>
Simulated ecology-driven sympatric speciation


  We introduce a multi-locus genetically acquired phenotype, submitted to
mutations and with selective value, in an age-structured model for biological
aging. This phenotype describes a single-trait effect of the environment on an
individual, and we study the resulting distribution of this trait among the
population. In particular, our simulations show that the appearance of a double
phenotypic attractor in the ecology induces the emergence of a stable
polymorphism, as observed in the Galapagos finches. In the presence of this
polymorphism, the simulations generate short-term speciation, when mating
preferences are also allowed to suffer mutations and acquire selective value.

</DOC>
<DOC>
<DOCNO> 84964 </DOCNO>
Black hole horizon and space-time foam


  We introduce, by means of the Brans-Dicke scalar field, space-time
fluctuations at scale comparable to Planck length near the event horizon of a
black hole and examine their dramatic effects.

</DOC>
<DOC>
<DOCNO> 68421 </DOCNO>
Threshold $pp\to pp\pi^0$ up to one-loop accuracy


  The $pp\to pp\pi^0$ cross section near threshold is computed up to one-loop
order including the initial and final state interactions using the hybrid heavy
baryon chiral perturbation theory and the counting rule a la Weinberg. With the
counter terms whose coefficients are fixed by the resonance-saturation
assumption, we find that the one-loop contributions are as important as the
tree-order contribution and bring the present theoretical estimation of the
total cross section close to the experimental data. The short-ranged
contributions are controlled by means of a cutoff, and a mild cutoff dependence
is observed when all diagrams of the given chiral order are summed. To the
order treated, however, the expansion is found to converge rather slowly,
calling for further studies of the process.

</DOC>
<DOC>
<DOCNO> 118013 </DOCNO>
Tully-Fisher Relation and its Implications for Halo Density Profile and


  We show that the Tully-Fisher relation observed for spiral galaxies can be
explained in the current scenario of galaxy formation without invoking subtle
assumptions, provided that galactic-sized dark haloes have shallow, core-like
central profiles, with a core radius proportional to halo circular velocity. In
such a system, both disk and halo contribute significantly to the maximum
rotation of the disk, and the interaction between the disk and halo components
acts to reduce the scatter in the Tully-Fisher relation. With model parameters
chosen in plausible ranges, the model can well accommodate the zero-point,
slope, scatter of the observed Tully-Fisher relation, as well as the large
range of disk sizes. The model predicts that LSB disks obey a Tully-Fisher
relation similar to that of normal disks, if disk mass-to-light ratio is
properly taken into account. The halo profile required by the Tully-Fisher
relation is as shallow as that required by the rotation curves of faint disks,
but much shallower than that predicted by conventional CDM models. Our results
cannot be explained by some of the recent proposals for resolving the conflict
between conventional CDM models and the rotation-curve shapes of faint
galaxies. If dark matter self-interaction (either scattering or annihilation)
is responsible for the shallow profile, the observed Tully-Fisher relation
requires the interaction cross section \sigma_X to satisfy
<\sigma_{X}|v|>/m_{X}~10^{-16} cm^3/s/GeV.

</DOC>
<DOC>
<DOCNO> 170803 </DOCNO>
Is there emitted radiation in Unruh effect?


  The thermal radiance felt by a uniformly accelerated
detector/oscillator/atom--the Unruh effect-- is often mistaken to be some
emitted radiation detectable by an observer/probe/sensor. Here we show by an
explicit calculation of the energy momentum tensor of a quantum scalar field
that, at least in 1+1 dimension, while a polarization cloud is found to exist
around the particle trajectory, there is no emitted radiation from a uniformly
accelerated oscillator in equilibrium conditions. Under nonequilibrium
conditions which can prevail for non-uniformly accelerated trajectories or
before the atom or oscillator reaches equilibrium, there is conceivably
radiation emitted, but that is not what Unruh effect entails.

</DOC>
<DOC>
<DOCNO> 12218 </DOCNO>
Some Aspects of Wigner Cristal Work


  We give a brief account on the importance of surface effects from homogeneous
background charge and assess the role of numerical work for Wigner cristal
transitions. We signal work from the 1960s on the impossibility of a Wigner
Cristal thermodynamic phase and suggest a possible research direction for
investigation of cristalline electron behaviour.

</DOC>
<DOC>
<DOCNO> 8199 </DOCNO>
Critical current of a superconductor measured via injection of spin


  In this paper we report a direct evidence of the suppression of critical
current due to pair-breaking in a superconducting micro-bridge when the
measurement is carried out by injecting spin polarised carriers instead of
normal electrons. A thin layer of La0.7Ca0.3MnO3 was used as the source of spin
polarised carriers. The micro-bridge was formed on the DyBa2Cu3O7-d thin film
by photo-lithographic techniques. The design of our spin-injection device
allowed us to inject spin-polarised carriers from the La0.7Ca0.3MnO3 layer
directly to the DyBa2Cu3O7- d micro-bridge (without any insulating buffer
layer) making it possible to measure the critical current when polarised
electrons alone are injected into the superconductor. Our results confirm the
role of polarised carriers in breaking the Cooper pairs in the superconductor.

</DOC>
<DOC>
<DOCNO> 102038 </DOCNO>
Geometrization of 3-dimensional orbifolds, Part II


  The purpose of this article is to give a proof of the Orbifold Theorem
announced by Thurston in late 1981: If $O$ is a compact, connected, orientable,
irreducible and topologically atoroidal 3-orbifold with non-empty ramification
locus, then $O$ is geometric. As a corollary, any smooth orientation preserving
non-free finite group action on $S^3$ is conjugate to an orthogonal action.

</DOC>
<DOC>
<DOCNO> 40159 </DOCNO>
A Measurement of the b-quark Mass from Hadronic Z Decays


  Hadronic Z decay data taken with the ALEPH detector at LEP1 are used to
measure the three-jet rate as well as moments of various event-shape variables.
The ratios of the observables obtained from b-tagged events and from an
inclusive sample are determined. The mass of the b quark is extracted from a
fit to the measured ratios using a next-to-leading order prediction including
mass effects. Taking the first moment of the y3 distribution, which is the
observable with the smallest hadronization corrections and systematic
uncertainties, the result is: mb(MZ) = [3.27+-0.22(stat)
+-0.22(exp)+-0.38(had)+-0.16(theo)] GeV/c2. The measured ratio is alternatively
employed to test the flavour independence of the strong coupling constant for b
and light quarks.

</DOC>
<DOC>
<DOCNO> 8551 </DOCNO>
Stripes in Quantum Hall Double Layer Systems


  We present results of a study of double layer quantum Hall systems in which
each layer has a high-index Landau level that is half-filled. Hartree-Fock
calculations indicate that, above a critical layer separation, the system
becomes unstable to the formation of a unidirectional coherent charge density
wave (UCCDW), which is related to stripe states in single layer systems. The
UCCDW state supports a quantized Hall effect when there is tunneling between
layers, and is {\it always} stable against formation of an isotropic Wigner
crystal for Landau indices $N \ge 1$. The state does become unstable to the
formation of modulations within the stripes at large enough layer separation.
The UCCDW state supports low-energy modes associated with interlayer coherence.
The coherence allows the formation of charged soliton excitations, which become
gapless in the limit of vanishing tunneling. We argue that this may result in a
novel {\it ``critical Hall state''}, characterized by a power law $I-V$ in
tunneling experiments.

</DOC>
<DOC>
<DOCNO> 118582 </DOCNO>
The Cosmic Ray - X-ray Connection: Effects of Nonlinear Shock


  Cosmic-ray production in young supernova remnant (SNR) shocks is expected to
be efficient and strongly nonlinear. In nonlinear, diffusive shock
acceleration, compression ratios will be higher and the shocked temperature
lower than test-particle, Rankine-Hugoniot relations predict. Furthermore, the
heating of the gas to X-ray emitting temperatures is strongly coupled to the
acceleration of cosmic-ray electrons and ions, thus nonlinear processes which
modify the shock, influence the emission over the entire band from radio to
gamma-rays and may have a strong impact on X-ray line models. Here we apply an
algebraic model of nonlinear acceleration, combined with SNR evolution, to
model the radio and X-ray continuum of Kepler's SNR.

</DOC>
<DOC>
<DOCNO> 170100 </DOCNO>
On Non Efficiency of Quantum Computer


  The previously proposed Heisenberg-type relation $ E_c t_c >> \hbar {\cal C}$
for the energy used by a quantum computer, the total computation time and the
logical ("classical") complexity of the problem is verified for the following
examples of quantum computations: preparation of the input state, two
Hamiltonian versions of the Grover's algorithm, a model of "quantum telephone
directory", a quantum-optical device factorizing numbers and the Shor's
algorithm.

</DOC>
<DOC>
<DOCNO> 121903 </DOCNO>
The Peak Brightness and Spatial Distribution of AGB Stars Near the


  The bright stellar content near the center of the Local Group elliptical
galaxy M32 is investigated with 0.12 arcsec FWHM H and K images obtained with
the Gemini Mauna Kea telescope. Stars with K = 15.5, which are likely evolving
near the tip of the asymptotic giant branch (AGB), are resolved to within 2
arcsec of the nucleus, and it is concluded that the peak stellar brightness
near the center of M32 is similar to that in the outer regions of the galaxy.
Moreover, the projected density of bright AGB stars follows the visible light
profile to within 2 arcsec of the nucleus, indicating that the brightest stars
are well mixed throughout the galaxy. Thus, there is no evidence for an age
gradient, and the radial variations in spectroscopic indices and ultraviolet
colors that have been detected previously must be due to metallicity and/or
some other parameter. We suggest that either the bright AGB stars formed as
part of a highly uniform and coherent galaxy-wide episode of star formation, or
they originated in a separate system that merged with M32.

</DOC>
<DOC>
<DOCNO> 170267 </DOCNO>
Comment on "Conceptual Inadequacy of Shannon Information ..." by C.


  It is pointed out that the case for Shannon entropy and von Neumann entropy,
as measures of uncertainty in quantum mechanics, is not as bleak as suggested
in quant-ph/0006087. The main argument of the latter is based on one particular
interpretation of Shannon's H-function (related to consecutive measurements),
and is shown explicitly to fail for other physical interpretations. Further, it
is shown that Shannon and von Neumann entropies have in fact a common
fundamental significance, connected to the existence of a unique geometric
measure of uncertainty for classical and quantum ensembles. Some new properties
of the ``total information'' measure proposed in quant-ph/0006087 are also
given.

</DOC>
<DOC>
<DOCNO> 12199 </DOCNO>
Symmetries and Triplet Dispersion in a Modified Shastry-Sutherland Model


  We investigate the one-triplet dispersion in a modified Shastry-Sutherland
Model for SrCu_2(BO_3)_2 by means of a series expansion about the limit of
strong dimerization. Our perturbative method is based on a continuous unitary
transformation that maps the original Hamiltonian to an effective, energy
quanta conserving block diagonal Hamiltonian H_{eff}. The dispersion splits
into two branches which are nearly degenerated. We analyse the symmetries of
the model and show that space group operations are necessary to explain the
degeneracy of the dispersion at k=0 and at the border of the magnetic Brillouin
zone. Moreover, we investigate the behaviour of the dispersion for small |k|
and compare our results to INS data.

</DOC>
<DOC>
<DOCNO> 71068 </DOCNO>
QCD coupling up to third order in standard and analytic perturbation


  We analyze two sets of specific functions, that/which form the basis of the
nonpower asymptotic expansions both in the timelike and spacelike regions for
single scale dependent QCD observables in the Shirkov--Solovtsov's Analytic
Perturbation Theory (APT) free of unphysical singularities. These functions are
explicitly derived up to the third order in the closed form in terms of the
Lambert-W function. As an input we used the exact two loop and the three loop
(corresponding to Pad\'e transformed beta-function) RG solutions for common
invariant coupling \alpha_s. The elegant recurrence formulas, helpful for
numerical analysis, are obtained for the both sets of the APT functions. Then
we construct the global versions of APT functions using the continuity
conditions (at the quark thresholds) on the \alpha_s in the \bar{MS} scheme and
give numerical results. For first three of these functions \mathfrak{A}_n(s)
and {\cal A}_n(Q^2); n=1,2,3 in the large interval of the momentum transfer and
energy (1 GeV <Q,{\sqrt s}< 170 GeV), numerical tables are presented. From
these we observe that, for the timelike arguments, the differences between
functions \mathfrak{A}_n(s) and the corresponding powers of the standard
iteratively approximated coupling \alpha_s^n(s) are not negligible even for
moderate energies in the five--flavor region.

</DOC>
<DOC>
<DOCNO> 40646 </DOCNO>
Measurement of Neutral and Charged Current Cross Sections in


  The inclusive e^-p single and double differential cross sections for neutral
and charged current processes are measured with the H1 detector at HERA, in the
range of four-momentum transfer squared Q^2 between 150 and 30000 GeV^2, and
Bjorken x between 0.002 and 0.65. The data were taken in 1998 and 1999 with a
centre-of-mass energy of 320 GeV and correspond to an integrated luminosity of
16.4 pb^(-1). The data are compared with recent measurements of the inclusive
neutral and charged current e^+p cross sections. For Q^2>1000 GeV^2 clear
evidence is observed for an asymmetry between e^+p and e^-p neutral current
scattering and the generalised structure function xF_3 is extracted for the
first time at HERA. A fit to the charged current data is used to extract a
value for the W boson propagator mass. The data are found to be in good
agreement with Standard Model predictions.

</DOC>
<DOC>
<DOCNO> 11189 </DOCNO>
Duality in the Azbel-Hofstadter problem and the two-dimensional d-wave


  A single-parameter family of lattice-fermion model is constructed. It is a
deformation of the Azbel-Hofstadter problem by a parameter $h={$B%((BDelta}/t$
(quantum parameter). A topological number is attached to each energy band. A
duality between the classical limit ($h=+0$) and the quantum limit ($h=1$) is
revealed in the energy spectrum and the topological number. The model has a
close relation to the two-dimensional d-wave superconductivity with a magnetic
field. Making use of the duality and a topological argument, we shed light on
how the quasiparticles with a magnetic field behave especially in the quantum
limit.

</DOC>
<DOC>
<DOCNO> 116949 </DOCNO>
The DARHT Phase 2 Linac


  The second phase accelerator for the Dual Axis Hydrodynamic Test facility
(DARHT) is designed to provide an electron beam pulse that is 2 microsec long,
2kA, and 20 MeV in particle energy. The injector provides 3.2 MeV so that the
linac need only provide 16.8 MeV. The linac is made with two types of induction
accelerator cells. The first block of 8 cells have a 14 in. beam pipe compared
to 10 in. in the remaining 80 cells. The other principal difference is that the
first 8 cells have reduced volt-sec in their induction cores as a result of a
larger diameter beam pipe. The cells are designed for very reliable high
voltage operation. The insulator is Mycalex. Results from prototype tests are
given including results from solenoid measurements. Each cell contains a
solenoid for beam transport and a set of x-y correction coils to reduce
corkscrew motion. Details of tests to determine RF mode impedances relevant to
BBU generation are given. Blocks of cells are separated by "intercells" some of
which contain transport solenoids. The intercells provide vacuum pumping
stations as well. Issues of alignment and installation are discussed.

</DOC>
<DOC>
<DOCNO> 118950 </DOCNO>
Constraining the Accretion Rate Onto Sagittarius A* Using Linear


  Two possible explanations for the low luminosity of the supermassive black
hole at the center of our galaxy are (1) an accretion rate of order the
canonical Bondi value (roughly 10^{-5} solar masses per year), but a very low
radiative efficiency for the accreting gas or (2) an accretion rate much less
than the Bondi rate. Both models can explain the broad-band spectrum of the
Galactic Center. We show that they can be distinguished using the linear
polarization of synchrotron radiation. Accretion at the Bondi rate predicts no
linear polarization at any frequency due to Faraday depolarization. Low
accretion rate models, on the other hand, have much lower gas densities and
magnetic field strengths close to the black hole; polarization may therefore be
observable at high frequencies. If confirmed, a recent detection of linear
polarization from Sgr A$^*$ above 150 GHz argues for an accretion rate of order
10^{-8} solar masses per year, much less than the Bondi rate. This test can be
applied to other low-luminosity galactic nuclei.

</DOC>
<DOC>
<DOCNO> 118577 </DOCNO>
A Very Fast and Momentum-Conserving Tree Code


  The tree code for the approximate evaluation of gravitational forces is
extended and substantially accelerated by including mutual cell-cell
interactions. These are computed by a Taylor series in Cartesian coordinates
and in a completely symmetric fashion, such that Newton's third law is
satisfied by construction and hence momentum exactly conserved. The
computational effort is further reduced by exploiting the mutual symmetry of
the interactions. For typical astrophysical problems with N=10^5 and at the
same level of accuracy, the new code is about four times faster than the tree
code. For large N, the computational costs are found to scale almost linearly
with N, which can also be supported by a theoretical argument, and the
advantage over the tree code increases with ever larger N.

</DOC>
<DOC>
<DOCNO> 39674 </DOCNO>
Single-W Production and Fermion-Loop Scheme: Numerical Results


  The single-W production mechanism is synonymous to the electron-positron
annihilation into electron, neutrino and a W boson with the outgoing electron
lost in a small cone around the beam direction. It requires a Renormalization
Scheme that preserves gauge invariance and fermion masses cannot be neglected
in the calculation. A recently proposed generalization of the so-called
Fermion-Loop scheme is applied to the evaluation of observables at LEP 2
energies. Single-W processes are dominated by a regime of low momentum transfer
of the outgoing electron and any high-energy Renormalization Scheme fails to
give the correct description of the scale. The Fermion-Loop scheme
automatically converts all couplings of the theory into couplings that are
running at the appropriate scale. Therefore, in addition to represent the only
scheme fully justified on a field-theoretical basis, the Fermion-Loop is the
best starting point to include radiative corrections into single-W production.
Numerical results are presented, showing a decrease in the predictions that can
be sizeable. There is no naive and overall rescaling of the e.m. coupling
constant, in any pragmatic scheme, that can reproduce the Fermion-Loop results,
at the requested accuracy, for all configurations and for all kinematical cuts.

</DOC>
<DOC>
<DOCNO> 84784 </DOCNO>
Newtonian Analysis of Gravitational Waves from Naked Singularity


  Spherical dust collapse generally forms a shell focusing naked singularity at
the symmetric center. This naked singularity is massless. Further the Newtonian
gravitational potential and speed of the dust fluid elements are everywhere
much smaller than unity until the central shell focusing naked singularity
formation if an appropriate initial condition is set up. Although such a
situation is highly relativistic, the analysis by the Newtonian approximation
scheme is available even in the vicinity of the space-time singularity. This
remarkable feature makes the analysis of such singularity formation very easy.
We investigate non-spherical even-parity matter perturbations in this scheme by
complementary using numerical and semi-analytical approaches, and estimate
linear gravitational waves generated in the neighborhood of the naked
singularity by the quadrupole formula. The result shows good agreement with the
relativistic perturbation analysis recently performed by Iguchi et al. The
energy flux of the gravitational waves is finite but the space-time curvature
carried by them diverges.

</DOC>
<DOC>
<DOCNO> 120107 </DOCNO>
Discovery of a Classic FR-II Broad Absorption Line Quasar from the FIRST


  We have discovered a remarkable quasar, FIRST J101614.3+520916, whose optical
spectrum shows unambiguous broad absorption features while its double-lobed
radio morphology and luminosity clearly indicate a classic Fanaroff-Riley Type
II radio source. Its radio luminosity places it at the extreme of the recently
established class of radio-loud broad absorption line quasars (Becker et al.
1997, 2000; Brotherton et al. 1998). Because of its hybrid nature, we speculate
that FIRST J101614.3+520916 is a typical FR-II quasar which has been
rejuvenated as a broad absorption line (BAL) quasar with a Compact Steep
Spectrum core. The direction of the jet axis of FIRST J101614.3+520916 can be
estimated from its radio structure and optical brightness, indicating that we
are viewing the system at a viewing angle of > 40 degrees. The position angles
of the radio jet and optical polarization are not well-aligned, differing by 20
to 30 degrees. When combined with the evidence presented by Becker et al.
(2000) for a sample of 29 BAL quasars showing that at least some BAL quasars
are viewed along the jet axis, the implication is that no preferred viewing
orientation is necessary to observe BAL systems in a quasar's spectrum. This,
and the probable young nature of compact steep spectrum sources, leads
naturally to the alternate hypothesis that BALs are an early stage in the lives
of quasars.

</DOC>
<DOC>
<DOCNO> 8279 </DOCNO>
Rouse Chains with Excluded Volume Interactions: Linear Viscoelasticity


  Linear viscoelastic properties for a dilute polymer solution are predicted by
modeling the solution as a suspension of non-interacting bead-spring chains.
The present model, unlike the Rouse model, can describe the solution's
rheological behavior even when the solvent quality is good, since excluded
volume effects are explicitly taken into account through a narrow Gaussian
repulsive potential between pairs of beads in a bead-spring chain. The use of
the narrow Gaussian potential, which tends to the more commonly used
delta-function repulsive potential in the limit of a width parameter "d" going
to zero, enables the performance of Brownian dynamics simulations. The
simulations results, which describe the exact behavior of the model, indicate
that for chains of arbitrary but finite length, a delta-function potential
leads to equilibrium and zero shear rate properties which are identical to the
predictions of the Rouse model. On the other hand, a non-zero value of "d"
gives rise to a prediction of swelling at equilibrium, and an increase in zero
shear rate properties relative to their Rouse model values. The use of a
delta-function potential appears to be justified in the limit of infinite chain
length. The exact simulation results are compared with those obtained with an
approximate solution which is based on the assumption that the non-equilibrium
configurational distribution function is Gaussian. The Gaussian approximation
is shown to be exact to first order in the strength of excluded volume
interaction, and is found to be accurate above a threshold value of "d", for
given values of chain length and strength of excluded volume interaction.

</DOC>
<DOC>
<DOCNO> 101611 </DOCNO>
The Szlenk index and local l_1-indices


  We introduce two new local l_1-indices of the same type as the Bourgain l_1
index; the l_1^+-index and the l_1^+-weakly null index. We show that the
l_1^+-weakly null index of a Banach space X is the same as the Szlenk index of
X, provided X does not contain l_1. The l_1^+-weakly null index has the same
form as the Bourgain l_1 index: if it is countable it must take values
omega^alpha for some alpha<omega_1. The different l_1-indices are closely
related and so knowing the Szlenk index of a Banach space helps us calculate
its local l_1-index, via the l_1^+-weakly null index. We show that
I(C(omega^{omega^alpha}))=omega^{1+alpha+1}.

</DOC>
<DOC>
<DOCNO> 10601 </DOCNO>
Non-perturbative saddle point for the effective action of disordered and


  We find a non-perturbative saddle-point solution for the non-linear sigma
model proposed by Finkelstein for interacting and disordered electronic
systems. Spin rotation symmetry, present in the original saddle point solution,
is spontaneously broken at one-loop, as in the Coleman-Weinberg mechanism. The
new solution is singular in both the disorder and triplet interaction
strengths, and it also explicitly demonstrates that a non-trivial ferromagnetic
state appears in a theory where the disorder average is carried out from the
outset.

</DOC>
<DOC>
<DOCNO> 71424 </DOCNO>
Large nu_mu->nu_tau and nu_e->nu_tau transitions in short-baseline


  Considering four-neutrino schemes of type 3+1, we identify four small regions
of the neutrino mixing parameter space compatible with all data. Assuming a
small mixing between the sterile neutrino and the isolated mass eigenstate we
show that large nu_mu->nu_tau and nu_e->nu_tau transitions are predicted in
short-baseline experiments and could be observed in the near future in
dedicated experiments. We discuss also implications for solar, atmospheric and
long-baseline neutrino experiments and we present a formalism that allows to
describe in 3+1 schemes atmospheric neutrino oscillations, long-baseline nu_mu
disappearance and nu_mu->nu_tau transitions in matter.

</DOC>
<DOC>
<DOCNO> 116266 </DOCNO>
Teaching "Symmetry" in the Introductory Physics Curriculum


  Modern physics is largely defined by fundamental symmetry principles and
Noether's Theorem. Yet these are not taught, or rarely mentioned, to beginning
students, thus missing an opportunity to reveal that the subject of physics is
as lively and contemporary as molecular biology, and as beautiful as the arts.
We prescribe a symmetry module to insert into the curriculum, of a week's
length.

</DOC>
<DOC>
<DOCNO> 67810 </DOCNO>
Fluctuations and Phase Transition Dynamics


  Kibble and Zurek have provided a unifying causal picture for the appearance
of classical defects like cosmic strings or vortices at the onset of phase
transitions in relativistic QFT and condensed matter systems respectively. In
condensed matter the predictions are partially supported by agreement with
experiments in superfluid helium. We provide an alternative picture for the
initial appearance of defects that supports the experimental evidence. When the
original predictions fail, this is understood, in part, as a consequence of
thermal fluctuations (noise), which play a comparable role in both condensed
matter and QFT.

</DOC>
<DOC>
<DOCNO> 118000 </DOCNO>
Resolved Spectroscopy of the Narrow-Line Region in NGC 1068: Kinematics


  We have determined the radial velocities of the [O III] emitting gas in the
inner narrow-line region (NLR) of the Seyfert 2 galaxy NGC 1068, along a slit
at position angle of 202 degrees, from STIS observations at a spatial
resolution of 0.1 arcsec and a spectral resolving power of approximately 1000.
We use these data to investigate the kinematics of the NLR within 6 arcsec (430
pc) of the nucleus. The emission-line knots show evidence for radial
acceleration, to a projected angular distance of 1.7 arcsec in most cases,
followed by deceleration that approaches the systemic velocity at a projected
distance of about 4 arcsec. We find that a simple kinematic model of biconical
radial outflow can match the general trend of observed radial velocities. In
this model, the emitting material is evacuated along the bicone axis, and the
axis is inclined 5 degrees out of the plane of the sky. The acceleration of the
emission-line clouds provides support for dynamical models that invoke
radiation and/or wind pressure. We suggest that the deceleration of the clouds
is due to their collision with a patchy and anistropically distributed ambient
medium.

</DOC>
<DOC>
<DOCNO> 117377 </DOCNO>
On the FIR emission from intracluster dust


  We make predictions for the diffuse far-infrared (FIR) emission from dust in
the intracluster medium (ICM) of the Virgo cluster using detailed information
on potential dust sources, grain heating and sputtering rates available for
this cluster from recent optical and X-ray studies. We show that the infrared
emission from dust injected by sources inside the core region of the Virgo
cluster is a factor of 10 below the detection limit of currently available
telescopes. The outer regions of dynamically young clusters like the Virgo
cluster have a further potential source of intracluster grains since they are
still accreting freshly infalling spiral galaxies which are presumably
contained in an accreting intergalactic medium (IGM). We show that cosmic ray
driven winds from the infalling spirals can inject grains into a subvirial IGM
that is external to the observed X-ray-emitting ICM. Sputtering during the
injection process and in the IGM is weak, so that the injected grains should
accumulate in the IGM until the infall brings them into contact with the hot
ICM. This effect dominates the dust injection rate from known sources embedded
in the hot Virgo ICM. Thus, any detection of diffuse IR emission would probe
the current dust accretion rate for the cluster, acting as an indicator of the
youth and the dynamical state of the cluster. The predictions for the Virgo
cluster are generalised to other clusters and the possibility of detection of
dynamically young clusters at cosmological distances is discussed.

</DOC>
<DOC>
<DOCNO> 9820 </DOCNO>
Adiabatic compression of a trapped Fermi gas


  We propose a method to reach conditions of high degeneracy in a trapped Fermi
gas, based on the adiabatic transfer of atoms from a magnetic to a tighter
optical trap. The transformation yields a large increase of the Fermi energy,
without a significant change of the temperature. The large enhancement of the
central density emphasizes the role of the interactions and makes the system
much closer to the BCS transition. An estimate of the time needed to achieve
the conditions of adiabaticity is also given.

</DOC>
<DOC>
<DOCNO> 84442 </DOCNO>
Naked singularities in higher dimensional inhomogeneous dust collapse


  We investigate the occurrence and nature of a naked singularity in the
gravitational collapse of an inhomogeneous dust cloud described by a non
self-similar higher dimensional Tolman spacetime. The necessary condition for
the formation of a naked singularity or a black hole is obtained. The naked
singularities are found to be gravitationally strong in the sense of Tipler and
provide another example that violates the cosmic censorship conjecture.

</DOC>
<DOC>
<DOCNO> 69130 </DOCNO>
QCD analysis of the diffractive structure functions measured at HERA and


  The 1994 data published by the H1 collaboration are compared with models
based on Regge phenomenology. The $x_{\PO}$ dependence of the data can be
described in a model based on the exchange of a dominant diffractive (pomeron)
trajectory with additional sub-leading reggeon contributions. The dynamics of
the Pomeron structure is studied within the framework of perturbative QCD and
new parton distributions are obtained. These parton distributions will allow a
direct test of factorisation breaking at Tevatron.

</DOC>
<DOC>
<DOCNO> 7614 </DOCNO>
Motional effects of single trapped atomic/ionic qubit


  We investigate theoretical decoherence effects of the motional degrees of
freedom of a single trapped atomic/ionic electronically coded qubit. For single
bit rotations from a resonant running wave laser field excitation, we found the
achievable fidelity to be determined by a single parameter characterized by the
motional states. Our quantitative results provide a useful realistic view for
current experimental efforts in quantum information and computing.

</DOC>
<DOC>
<DOCNO> 39768 </DOCNO>
A New Approach to Background Subtraction in Low-Energy Neutrino


  We discuss a new method to extract neutrino signals in low energy
experiments. In this scheme the symmetric nature of most backgrounds allows for
direct cancellation from data. The application of this technique to the Palo
Verde reactor neutrino oscillation experiment allowed us to reduce the
measurement errors on the anti-neutrino flux from $\sim 20$% to $\sim 10$%. We
expect this method to substantially improve the data quality in future low
background experiments such as KamLAND and LENS.

</DOC>
<DOC>
<DOCNO> 11476 </DOCNO>
Phase-Induced (In)-Stability in Coupled Parametric Oscillators


  We report results on a model of two coupled oscillators that undergo periodic
parametric modulations with a phase difference $\theta$. Being to a large
extent analytically solvable, the model reveals a rich $\theta$ dependence of
the regions of parametric resonance. In particular, the intuitive notion that
anti-phase modulations are less prone to parametric resonance is confirmed for
sufficiently large coupling and damping. We also compare our results to a
recently reported mean field model of collective parametric instability,
showing that the two-oscillator model can capture much of the qualitative
behavior of the infinite system.

</DOC>
<DOC>
<DOCNO> 121636 </DOCNO>
Where are the absorbers towards Q2302+029?


  We present images and spectroscopy of objects close to the sightline of
Q2302+029 in order to search for galaxies responsible for the remarkable z=0.7
high-ionization absorption line system found by Jannuzi et al (1996). This
system shows `normal' narrow OVI, NV, and CIV lines superimposed on broader
(3,000-5,000 km/s wide), unsaturated absorption troughs some 56,000 km/s away
from the QSO emission redshift (z=1.052). Despite reaching sensitivities
sufficient to detect 1/10 L* galaxies in the optical and 1/20 L* in the
infra-red, we are unable to detect any obvious bright galaxies which might be
responsible for the absorption beyond ~ 6 h-1 kpc of the sightline. This
supports the hypotheses that the absorption is either intrinsic to the QSO, or
arises in intracluster gas. Adopting either explanation is problematic: in the
first case, `associated' absorption at such high ejection velocities is hard to
understand, and challenges the conventional discrimination between intrinsic
and intervening absorbers; in the second case, the gas must reside in a ~ 40
h-1 Mpc long filament aligned along the line of sight in order to reproduce the
broad absorption. Spectroscopy of objects beyond the immediate vicinity of the
QSO sightline reveals a galaxy cluster at z=0.59, which coincides with strong
Lya and more narrow high ionization lines in the quasar spectrum. Here too, the
lack of galaxies at distances comparable to those found for, e.g.,
Lya-absorbing galaxies, suggests that the absorption may arise from
intracluster gas unassociated with any individual galaxies.

</DOC>
<DOC>
<DOCNO> 8776 </DOCNO>
Coulomb drag between one-dimensional conductors


  We have analyzed Coulomb drag between currents of interacting electrons in
two parallel one-dimensional conductors of finite length $L$ attached to
external reservoirs. For strong coupling, the relative fluctuations of electron
density in the conductors acquire energy gap $M$. At energies larger than
$\Gamma = const \times v_- \exp (-LM/v_-)/L + \Gamma_{+}$, where $\Gamma_{+}$
is the impurity scattering rate, and for $L>v_-/M$, where $v_-$ is the
fluctuation velocity, the gap leads to an ``ideal'' drag with almost equal
currents in the conductors. At low energies the drag is suppressed by coherent
instanton tunneling, and the zero-temperature transconductance vanishes,
indicating the Fermi liquid behavior.

</DOC>
<DOC>
<DOCNO> 12950 </DOCNO>
Theory of electrical spin injection: Tunnel contacts as a solution of


  Theory of electrical spin injection from a ferromagnetic (FM) metal into a
normal (N) conductor is presented. We show that tunnel contacts (T) can
dramatically increase spin injection and solve the problem of the mismatch in
the conductivities of a FM metal and a semiconductor microstructure. We also
present explicit expressions for the spin-valve resistance of FM-T-N- and
FM-T-N-T-FM-junctions with tunnel contacts at the interfaces and show that the
resistance includes both positive and negative contributions (Kapitza
resistance and injection conductivity, respectively).

</DOC>
<DOC>
<DOCNO> 70629 </DOCNO>
Small Violation of Universal Yukawa Coupling and Neutrino Large Mixing


  We assume the universal Yukawa coupling (democratic mass matrix) with small
violations for quarks, charged leptons and neutrinos masses. We could reproduce
the mass hierarchy for quark masses and V_{CKM} matrix elements precisely. We
adopt the see-saw mechanism for the explanation of smallness of neutrino masses
and introduce the right-handed Majorana neutrinos and Dirac neutrinos. We
assume the universal Yukawa coupling with small violations for Majorana and
Dirac neutrinos. We can get the hierarchy of charged lepton masses and
effective neutrino masses and the large mixing of neutrinos expressed in
V_{NMS}.

</DOC>
<DOC>
<DOCNO> 118237 </DOCNO>
Proper Motion of Water Masers Associated with IRAS 21391+5802: Bipolar


  We present VLBA observations of water maser emission associated with the
star-forming region IRAS 21391+5802, which is embedded in a bright rimmed
cometary globule in IC1396. The angular resolution of the maps is about 0.8
mas, corresponding to a spatial resolution of about 0.6 AU, at an estimated
distance of 750 pc. Proper motions are derived for 10 maser features identified
consistently over three epochs, which were separated by intervals of about one
month. The masers appear in four groups, which are aligned linearly on the sky,
roughly along a northeast-southwest direction, with a total separation of about
520 AU (about 0.7 arcseconds). The 3-D velocities of the masers have a maximum
value of about 42 km/s (about 9 AU/yr). The average error on the derived proper
motions is about 4 km/s. The overall pattern of proper motions is indicative of
a bipolar outflow. Proper motions of the masers in a central cluster, with a
projected extent of about 20 AU, show systematic deviations from a radial
outflow. However, we find no evidence of Keplerian rotation, as has been
claimed elsewhere. A nearly circular loop of masers lies near the middle of the
cluster. The radius of this loop is 1 AU and the line-of-sight velocities of
the masers in the loop are within 2 km/s of the systemic velocity of the
region. These masers presumably exist at the radial distance where significant
dust condensation occurs in the outflow emanating from the star.

</DOC>
<DOC>
<DOCNO> 119899 </DOCNO>
Thermal and Nonthermal X-Ray Emission in SNR RCW 86


  Supernova remnants may exhibit both thermal and nonthermal X-ray emission.
Such remnants can be distinguished by the weakness of their X-ray lines,
because of the presence of a strong nonthermal X-ray continuum. RCW 86 is a
remnant with weak lines, resulting in low and peculiar abundances when thermal
models alone are used to interpret its X-ray spectrum. This indicates the
presence of a strong nonthermal synchrotron continuum. We analyze ASCA X-ray
spectra of RCW 86 with the help of both nonequilibrium ionization thermal
models and nonthermal synchrotron models. A two-temperature thermal model and a
simple nonthermal model with an exponential cutoff (plus interstellar
absorption) give reasonable results. We obtain blast wave velocity of 800 km/s,
the shock ionization age of 1-3x10^11 s/cm^3, and the break in nonthermal
spectra at 2-4x10^16 Hz. The strength of nonthermal continuum correlates well
with the radio brightness in the bright SW section of the remnant. This is
convincing evidence for X-ray synchrotron emission in RCW 86.

</DOC>
<DOC>
<DOCNO> 12649 </DOCNO>
Random field O(N) spin model near four dimensions


  We study a random field O($N$) spin model with a replica mixing interaction
near four dimensions. The beta function indicates a breakdown of the
dimensional reduction. We calculate a two point correlation function with
connected and disconnected parts as a solution of the renormalization group
equation. The corresponding critical exponents are shown to satisfy
$\bar{\eta}=2 \eta$ at lowest order. We discuss agreement with several other
approaches.

</DOC>
<DOC>
<DOCNO> 83391 </DOCNO>
The Rectilinear Crossing Number of K_10 is 62


  A drawing of a graph G in the plane is said to be a rectilinear drawing of G
if the edges are required to be line segments (as opposed to Jordan curves). We
assume no three vertices are collinear. The rectilinear crossing number of G is
the fewest number of edge crossings attainable over all rectilinear drawings of
G. Thanks to Richard Guy, exact values of the rectilinear crossing number of
K_n, the complete graph on n vertices, for n = 3,...,9, are known (Guy 1972,
White and Beinke 1978, Finch 2000, Sloanes A014540). Since 1971, thanks to the
work of David Singer (1971, Gardiner 1986), the rectilinear crossing number of
K_10 has been known to be either 61 or 62, a deceptively innocent and
tantalizing statement. The difficulty of determining the correct value is
evidenced by the fact that Singer's result has withstood the test of time. In
this paper we use a purely combinatorial argument to show that the rectilinear
crossing number of K_10 is 62. Moreover, using this result, we improve an
asymptotic lower bound for a related problem. Finally, we close with some new
and old open questions that were provoked, in part, by the results of this
paper, and by the tangled history of the problem itself.

</DOC>
<DOC>
<DOCNO> 85085 </DOCNO>
Non-Abelian Black Holes with Magnetic Dipole Hair


  We construct static axially symmetric black holes in SU(2)
Einstein-Yang-Mills-Higgs theory. Located in between a monopole-antimonopole
pair, these black holes possess magnetic dipole hair. The difference of their
mass and their horizon mass equals the mass of the regular
monopole-antimonopole solution, as expected from the isolated horizon
framework.

</DOC>
<DOC>
<DOCNO> 69540 </DOCNO>
Gravitational waves from inflation on the brane


  We discuss the evolution of gravitational waves in a brane-world cosmology
embedded in five-dimensional anti-de Sitter spacetime. We show that during
slow-roll inflation, modelled as a period of quasi-de Sitter expansion on the
brane, there is a discrete normalizable massless graviton mode. There is a mass
gap due to the expansion, above which there is a continuum of massive modes.
Only the massless mode is `light' compared with the Hubble scale during
inflation, leading to the production of classical perturbations on large scales
from vacuum fluctuations on small scales. We calculate the amplitude of these
fluctuations at horizon-crossing and show that the standard four-dimensional
result is recovered at low energies, but the amplitude of the perturbations is
enhanced at high energies.

</DOC>
<DOC>
<DOCNO> 71896 </DOCNO>
A derivation of Regge trajectories in large-N transverse lattice QCD


  Large-N QCD is analysed in light-front coordinates with a transverse lattice
at strong coupling. The general formalism can be looked up on as a d+n
expansion with a stack of d-dimensional hyperplanes uniformly spaced in n
transverse dimensions. It can arise by application of the renormalisation group
transformations only in the transverse directions. At leading order in strong
coupling, the gauge field dynamics reduces to the constraint that only colour
singlet states can jump between the hyperplanes. With d=2, n=2 and large-N, the
leading order strong coupling results are simple renormalisations of those for
the 't Hooft model. The meson spectrum lies on a set of parallel trajectories
labeled by spin. This is the first derivation of the widely anticipated Regge
trajectories in a regulated systematic expansion in QCD.

</DOC>
<DOC>
<DOCNO> 120568 </DOCNO>
Magnetic Activity in Stars, Discs and Quasars


  Although magnetic fields in interstellar matter were postulated almost fifty
years ago, magnetohydrodynamic theory was then much hampered by our inability
to see what the magnetic field configurations were like and, after a decade of
innovative development, cynics, not without some justification, began to claim
that anything can happen when magnetism and an imaginative theorist get
together. Thus cosmic lightning in particular received a bad press. More
recently great advances in observational techniques that we shall hear of from
Title, Beck, Moran and Mirabel have enabled us to see not only the sun's
magnetic field with unprecedented clarity but the fields in galaxies, quasars
and microquasars are now measured and not merely figments of fertile
imaginations.

</DOC>
<DOC>
<DOCNO> 7751 </DOCNO>
Charge Fluctuations on Membrane Surfaces in Water


  We generalize the predictions for attractions between over-all neutral
surfaces induced by charge fluctuations/correlations to non-uniform systems
that include dielectric discontinuities, as is the case for mixed charged lipid
membranes in an aqueous solution. We show that the induced interactions depend
in a non-trivial way on the dielectric constants of membrane and water and show
different scaling with distance depending on these properties. The generality
of the calculations also allows us to predict under which dielectric conditions
the interaction will change sign and become repulsive.

</DOC>
<DOC>
<DOCNO> 178754 </DOCNO>
The Role of Meson Retardation in Deuteron Photodisintegration above Pion


  Photodisintegration of the deuteron above $\pi$ threshold is studied in a
coupled channel approach including $N \Delta$ and $\pi d$ channels with
consideration of pion retardation in potentials and exchange currents. A much
improved description of total and differential cross sections in the energy
region between $\pi$ threshold and 400-450 MeV is achieved. With respect to
polarization observables, the description of the linear photon asymmetry and
the proton polarization remains problematic.

</DOC>
<DOC>
<DOCNO> 118972 </DOCNO>
Four Measures of the Intracluster Medium Temperature and Their Relation


  We employ an ensemble of hydrodynamic cluster simulations to create spatially
and spectrally resolved images of quality comparable to Chandra's expected
performance. Emission from simulation mass elements is represented using the
XSPEC mekal program assuming 0.3 solar metallicity, and the resulting spectra
are fit with a single-temperature model. Despite significant departures from
isothermality in the cluster gas, single-temperature models produce acceptable
fits to 20,000 source photon spectra. The spectral fit temperature T_s is
generally lower than the mass weighted average temperature T_m due to the
influence of soft line emission from cooler gas being accreted as part of the
hierarchical clustering process. In a Chandra-like bandpass of 0.5 to 9.5 keV
we find a nearly uniform fractional bias of (T_m-T_s)/T_s = 20% with occasional
large deviations in smaller clusters. In the more traditional 2.0 to 9.5 keV
bandpass, the fractional deviation is scale-dependent and on average follows
the relation (T_m-T_s)/T_s = 0.2 log(T_m). This bias results in a spectral
mass-temperature relationship with slope about 1.6, intermediate between the
virial relation M ~ T_m^{3/2} and the observed relation M_{ICM} ~ T^2. Imaging
each cluster in the ensemble at 16 epochs in its evolutionary history, we
catalogue merger events with mass ratios exceeding 10% in order to investigate
the relationship between spectral temperature and proximity to a major merger
event. Clusters that are very cool relative to the mean mass-temperature
relationship lie preferentially close to a merger, suggesting a viable
observational method to cull a subset of dynamically young clusters from the
general population.

</DOC>
<DOC>
<DOCNO> 9743 </DOCNO>
Number of bonds in the site-diluted lattices: sampling and fluctuations


  We have calculated analytically the mean value and the variance of the number
of bonds on the lattices of dimension $d$ for the given occupation of sites. We
consider both kinds of site occupation: with the fixed concentration $n_s$ of
occupied sites and with the probability $p$ for a site to be occupied. We found
that the variance are smaller in the former case and not depends from the
dimensionality of the hypercubic lattice. Whereas in the last case it grows
with the space dimensionality. The ratio of variances are quite different in
the limit of $p\to 1$. Finally, we demonstrate the relevance of the level of
fluctuations on the precision of energy calculations for the Ising model in the
Monte Carlo simulations.

</DOC>
<DOC>
<DOCNO> 13119 </DOCNO>
Interpenetration of two chains different in sizes: Some Exact Results


  A model of two interacting polymer chains has been proposed to study the
effect of penetration of one chain in to the other. We show that small chain
penetrates more in comparison to the long chain. We also find a condition in
which both chains cannot grow on their own (or polymerize) but can grow
(polymerize) in zipped form.

</DOC>
<DOC>
<DOCNO> 100862 </DOCNO>
Monodromy Filtration and Positivity


  We study the notion of positivity for the l-adic cohomology of a variety over
a field of positive characteristic. This is motivated by Deligne's conjecture
on the purity of the monodromy filtration on the nearby cycles in the mixed
characteristic case. In the one-dimensional case, this is given by Weil's
theory of Riemann forms for abelian varieties, and the canonical pairing on the
cohomology of a curve is positive in this sense by Deligne, as was used by
Rapoport and Zink. In general we do not know the positivity except for the
Hodge index conjecture. We show that Deligne's monodromy conjecture can be
reduced to the standard conjectures.

</DOC>
<DOC>
<DOCNO> 69990 </DOCNO>
Probing nucleon strangeness in phi electroproduction


  We investigate $\phi$ meson electroproduction to probe the hidden strangeness
content of the nucleon. We found that even a small amount of the $s\bar{s}$
admixture in the nucleon wavefunction can lead to a significant change in
several double polarization asymmetries in $\phi$ electroproduction, which can
be tested experimentally at current electron facilities.

</DOC>
<DOC>
<DOCNO> 68378 </DOCNO>
The use of neutrino beams from muon storage rings


  I give a brief overview of the physics potential of short baseline
experiments at neutrino factories, i.e. facilities providing high energy and
high intensity neutrino beams, like the one planned to be built in connection
with the proposed high energy muon storage ring. These facilities would offer a
unique opportunity to perform new precision studies of QCD and electroweak
interactions. New types of measurements, such as studies of gluon density of
the nucleon via charmonium production and extractions of V_cb and V_ub CKM
matrix elements, will become possible. Interesting new physics scenarios can
also be explored.

</DOC>
<DOC>
<DOCNO> 80654 </DOCNO>
Towards the matrix model of M-theory on a lattice


  The Wilson discretization of the dimensionally reduced supersymmetric
Yang-Mills theory is constructed. This gives a lattice version of the matrix
model of M-theory. An SU(2) model is studied numerically in the quenched
approximation for D=4. The system shows canonical scaling in the continuum
limit. A clear signal for a prototype of the "black hole to strings" phase
transition is found. The pseudocritical temperature is determined and the
temperature dependence of the total size of the system is measured in both
phases. Further applications are outlined.

</DOC>
<DOC>
<DOCNO> 119424 </DOCNO>
Production of Lithium in the Galactic Disk


  We examine the evolution of Li in the Galactic disk,basing our model on the
compilation of Li v.Fe observations in stars of iron abundance ranging between
halo values,which give a baseline for the disk Li abundance,and 0.2 dex above
solar.The upper envelope of these observations is taken to represent the locus
of minimum stellar Li depletion,and thus to follow the Galactic IS Li
abundance.The most striking feature of this envelope is its steep rise between
Fe/H ~ -0.4 and -0.2,corresponding to a relatively late epoch.The Li abundance
increases by an order of magnitude,from its halo value of logLi ~2.2 to the
"current" value of ~3.2 within this narrow range of Fe abundances.It is well
known that spallation reactions between CNO and 4He in the ISM produce Li,but
models give a nearly tenfold shortfall for this process.The alpha+alpha fusion
reaction appeared to yield too much early Li or too little current Li.These
failures led to the exploration of stellar sources:supernovae,novae,and the He
flash phase in AGB stars.The Li-Fe envelope is a strong constraint on any
process.Our models can account for this in the context of disk chemical
evolution with a near constant or growing rate of low metallicity gas
infall,and a purely interstellar Li source: alpha-alpha fusion.The Li
production rate is found to be proportional to the gas expulsion rate from
intermediate and low mass stars.Low-energy alphas,emitted by these stars,but
accelerated in more energetic processes associated with SNe,or the bow-shocks
of stellar winds,can yield the observed abundance and its variation with Fe or
O.Our model is consistent with the cosmic ray spectrum in the few MeV
range,corrected for solar modulation and with new 7Li/6Li ratios found by
Knauth et al.(2000) in the local ISM.

</DOC>
<DOC>
<DOCNO> 70719 </DOCNO>
Analysis of oscillations of atmospheric neutrinos


  We briefly review the current status of standard oscillations of atmospheric
neutrinos in schemes with two, three, and four flavor mixing. It is shown that,
although the pure \nu_\mu-->\nu_\tau channel provides an excellent 2\nu fit to
the data, one cannot exclude, at present, the occurrence of additional
subleading \nu_\mu-->\nu_e oscillations (3\nu schemes) or of sizable
\nu_\mu-->\nu_s oscillations (4\nu schemes). It is also shown that the wide
dynamical range of energy and pathlength probed by the Super-Kamiokande
experiment puts severe constraints on nonstandard explanations of the
atmospheric neutrino data, with a few notable exceptions.

</DOC>
<DOC>
<DOCNO> 169589 </DOCNO>
Comment on "Giant absorption cross section of ultracold neutrons in


  Rauch et al (PRL 83, 4955, 1999) have compared their measurements of the Gd
cross section for Ultra-cold neutrons with an exptrapolation of the cross
section for thermal neutrons and interpreted the discrepancy in terms of
coherence properties of the neutron. We show the extrapolation used is based on
a misunderstanding and that coherence properties play no role in absorption.

</DOC>
<DOC>
<DOCNO> 152346 </DOCNO>
Capture of bulk geodesics by brane-world black holes


  In this note we study bulk timelike geodesics in the presence of a
brane-world black hole, where the brane-world is a two-brane moving in a
3+1-dimensional asymptotically $adS_4$ spacetime. We show that for a certain
range of the parameters measuring the black hole mass and bulk cosmological
constant, there exist stable timelike geodesics which orbit the black hole and
remain bound close to the two-brane.

</DOC>
<DOC>
<DOCNO> 170119 </DOCNO>
Symmetrizing The Symmetrization Postulate


  Reasonable requirements of (a) physical invariance under particle permutation
and (b) physical completeness of state descriptions, enable us to deduce a
Symmetric Permutation Rule(SPR): that by taking care with our state
descriptions, it is always possible to construct state vectors (or wave
functions) that are purely symmetric under pure permutation for all particles,
regardless of type distinguishability or spin. The conventional exchange
antisymmetry for two identical half-integer spin particles is shown to be due
to a subtle interdependence in the individual state descriptions arising from
an inherent geometrical asymmetry. For three or more such particles, however,
antisymmetrization of the state vector for all pairs simultaneously is shown to
be impossible and the SPR makes observably different predictions, although the
usual pairwise exclusion rules are maintained. The usual caveat of fermion
antisymmetrization - that composite integer spin particles (with fermionic
consitituents) behave only approximately like bosons - is no longer necessary.

</DOC>
<DOC>
<DOCNO> 150595 </DOCNO>
Aspects of the conformal operator product expansion in AdS/CFT


  We present a detailed analysis of a scalar conformal four-point function
obtained from AdS/CFT correspondence. We study the scalar exchange graphs in
AdS and discuss their analytic properties. Using methods of conformal partial
wave analysis, we present a general procedure to study conformal four-point
functions in terms of exchanges of scalar and tensor fields. The logarithmic
terms in the four-point functions are connected to the anomalous dimensions of
the exchanged fields. Comparison of the results from AdS graphs with the
conformal partial wave analysis, suggests a possible general form for the
operator product expansion of scalar fields in the boundary CFT.

</DOC>
<DOC>
<DOCNO> 68763 </DOCNO>
The pionium lifetime in generalized chiral perturbation theory


  Pionium lifetime corrections to the nonrelativistic formula are calculated in
the framework of the quasipotential-constraint theory approach. The calculation
extends an earlier evaluation, made in the scheme of standard chiral
perturbation theory, to the scheme of generalized chiral perturbation theory,
in which the quark condensate is left as a free parameter. The pionium lifetime
is calculated as a function of the combination $(a_0^0-a_0^2)$ of the $\pi\pi$
S-wave scattering lengths with isospin I=0,2.

</DOC>
<DOC>
<DOCNO> 69803 </DOCNO>
Effective Chiral Lagrangians and Lattice QCD


  We propose a general method to obtain accurate estimates for some of the
"low-energy constants" in the one-loop effective chiral Lagrangian by means of
simulating lattice QCD. In particular, the method is sensitive to those
constants whose values are required to test the hypothesis of a massless
up-quark. Initial tests performed in the quenched approximation confirm that
good statistical precision can be achieved. As a byproduct we obtain an
accurate estimate for the ratio of pseudoscalar decay constants, F_K/F_pi, in
the quenched approximation, which lies 10% below the experimental result. The
quantities that serve to extract the low-energy constants also allow a test of
the scaling behaviour of different discretizations of QCD and a search for the
effects of dynamical quarks.

</DOC>
<DOC>
<DOCNO> 83459 </DOCNO>
Optimal Buy-and-Hold Strategies for Financial Markets with Bounded Daily


  In the context of investment analysis, we formulate an abstract online
computing problem called a planning game and develop general tools for solving
such a game. We then use the tools to investigate a practical buy-and-hold
trading problem faced by long-term investors in stocks. We obtain the unique
optimal static online algorithm for the problem and determine its exact
competitive ratio. We also compare this algorithm with the popular dollar
averaging strategy using actual market data.

</DOC>
<DOC>
<DOCNO> 100250 </DOCNO>
Various doublings of Hopf Algebras. Algebras of Operators on Quantum


  Family of doublings of Hopf algeras based on the product of algebra and its
dual are constructed and studied. Special cases of these construction may be
considered as natural quantum analogs of rings of differential operators on
groups. Such constructions appeared in 1966-67 in the authors works in the
complex cobordism theory. These constructions do not leed to the Hopf algebras
(except of the special case of the Drinfeld's quantum double which is not the
same as the natural quantum analog of the ring of operators on groups).
However, they have important ''almost Hopf'' properties important in particular
in the topological and analytical applications.

</DOC>
<DOC>
<DOCNO> 39772 </DOCNO>
Spin alignment of $K^*(892)^\pm$ mesons produced in neutron-carbon


  A new precise measurements of spin density matrix element $\rho_{00}$ of
$K^*(892)^{\pm}$ mesons produced inclusively in neutron-carbon interactions at
\~60 GeV have been carried out in the EXCHARM experiment at the Serpukhov
accelerator. The values of $\rho_{00}$ obtained in the transversity frame are
$0.424\pm0.011(stat)\pm0.018(sys)$ for $K^*(892)^+$ and
$0.393\pm0.025(stat)\pm0.018(sys)$ for $K^*(892)^-$. Significant $P_T$
dependence of $\rho_{00}$ has been observed in $K^*(892)^+$ production.

</DOC>
<DOC>
<DOCNO> 84449 </DOCNO>
Mode solutions of the Klein-Gordon equation in warped spacetimes


  In order to reduce the Klein-Gordon equation (with minimal coupling), we
introduce a generalization of the so-called "mode solutions" that are
well-known in the special case of a Robertson-Walker universe. After separation
of the variables, we end up with a partial differential equation in lower
dimension. A reduced version of the Gordon current arises and is conserved.
When the first factor-manifold is Lorentzian, distinct modes appear as mutually
orthogonal in the sense of the sesquilinear form obtained from the customary
Gordon current. Moreover, a sesquilinear form is defined on the space of
solutions to the reduced equation. Extension of this picture to curvature
coupling is possible when the second factor-manifold has a constant scalar
curvature.

</DOC>
<DOC>
<DOCNO> 118007 </DOCNO>
NICMOS Imaging of a Damped Lyman-alpha Absorber at z=1.89 toward LBQS


  We report results of a high-resolution imaging search (in rest frame
H-$\alpha$ and optical continuum) for the galaxy associated with the damped
Lyman-$\alpha$ (DLA) absorber at $z=1.892$ toward the $z_{em}=2.543$ quasar
LBQS 1210+1731, using HST/NICMOS. After PSF subtraction, a feature is seen in
both the broad-band and narrow-band images, at a projected separation of
0.25$\arcsec$ from the quasar. If associated with the DLA, the object would be
$\approx 2-3$ $h_{70}^{-1}$ kpc in size with a flux of $9.8 \pm 2.4$ $\mu$Jy in
the F160W filter, implying a luminosity at $\lambda_{central}=5500$ {\AA} in
the rest frame of $1.5 \times 10^{10}$ $h_{70}^{-2}$ L$_{\odot}$ at $z=1.89$,
for $q_{0}=0.5$. However, no significant H-$\alpha$ emission is seen,
suggesting a low star formation rate (SFR) (3 $\sigma$ upper limit of 4.0
$h_{70}^{-2}$ M$_{\odot}$ yr$^{-1}$), or very high dust obscuration.
Alternatively, the object may be associated with the host galaxy of the quasar.
H-band images obtained with the NICMOS camera 2 coronagraph show a much fainter
structure $\approx 4-5$ $h_{70}^{-1}$ kpc in size and containing four knots of
continuum emission, located 0.7$\arcsec$ away from the quasar. We have probed
regions far closer to the quasar sight-line than in most previous studies of
high-redshift intervening DLAs. The two objects we report mark the closest
detected high-redshift DLA candidates yet to any quasar sight line. If the
features in our images are associated with the DLA, they suggest faint,
compact, somewhat clumpy objects rather than large, well-formed proto-galactic
disks or spheroids.

</DOC>
<DOC>
<DOCNO> 122134 </DOCNO>
Vacuum Selection by Collapsing


  In this talk, we discuss the possibility that the vacuum is dynamically
determined in the history of the universe. The point is that some of the
bubbles with a certain vacuum shrink by the evolution of the universe via
gravity and may become black holes. It is interesting that in many cases false
vacua are favored in the context of cosmology. By using this argument,
supersymmetry(SUSY), if it exists, can be broken cosmologically. This talk is
based on Ref.[1].

</DOC>
<DOC>
<DOCNO> 120955 </DOCNO>
Study of ammonia emission in the NGC 6334 region


  The region centered in the NGC 6334 I(N) radio continuum source was surveyed
in an extension of 6 arcmin in right ascension and 12 arcmin in declination, in
the NH3(J,K) = (1,1) transition, using the Itapetinga radio telescope. The
spectra show non-LTE behavior, and gradients of velocity and line-width were
detected along the region. A detailed analysis of the spectra showed that the
surveyed region is composed of at least three overlapped sources related to
regions that are in different stages of star formation: NGC 6334 I, associated
with an already known molecular bipolar outflow, NGC 6334 I(N)w, the brightest
ammonia source, coincidental with the continuum source NGC 6334 I(N), and NGC
6334 I(N)e, weaker, more extended and probably less evolved than the others.
The physical parameters of the last two sources were calculated in non-LTE
conditions, assuming that their spectra are the superposition of the narrow
line spectra produced by small dense clumps. The H2 density, NH3 column
density, kinetic temperature, diameter and mass of the clumps were found to be
very similar in the two regions, but the density of clumps is lower in the
probably less evolved source NGC 6334 I(N)e. Differences between the physical
parameters derived assuming LTE and non-LTE conditions are also discussed in
this work.

</DOC>
<DOC>
<DOCNO> 101244 </DOCNO>
A classification of classical representations for quantum-like systems


  For general non-classical systems, we study the different classical
representations that fulfill the specific context dependence imposed by the
hidden measurement system formalism introduced in quant-ph/0008061. We show
that the collection of non-equivalent representations has a poset structure. We
also show that in general, there exists no 'smallest' representation, since
this poset is not a semi-lattice. Then we study the possible representations of
quantum-like measurement systems. For example, we show that there exists a
classical representation of finite dimensional quantum mechanics with ${\Bbb
N}$ as a set of states for the measurement context, and we build an explicit
example of such a representation.

</DOC>
<DOC>
<DOCNO> 121607 </DOCNO>
The brighter side of sub-mm source counts: a SCUBA scan-map of the


  We present an 11 X 11 arcminute map centred on the Hubble Deep Field taken at
850 microns with the SCUBA camera on the JCMT. The map has an average one-sigma
sensitivity to point sources of about 2.3 mJy and thus probes the brighter end
of the sub-mm source counts. We find 7 sources with a flux greater than 9 mJy
(roughly 4 sigma), and therefore estimate N(>9 mJy)= 208 (+90/-72) per degree.
This result is consistent with work from other groups, but improves the
statistics at the bright end, and is suggestive of a steepening of the counts.

</DOC>
<DOC>
<DOCNO> 11327 </DOCNO>
Superconducting Phase with Fractional Vortices in the Frustrated Kagome


  In classical XY kagome antiferromagnets, there can be a novel low temperature
phase where $\psi^3=e^{i3\theta}$ has quasi-long-range order but $\psi$ is
disordered, as well as more conventional antiferromagnetic phases where $\psi$
is ordered in various possible patterns ($\theta$ is the angle of orientation
of the spin). To investigate when these phases exist in a physical system, we
study superconducting kagome wire networks in a transverse magnetic field when
the magnetic flux through an elementary triangle is a half of a flux quantum.
Within Ginzburg-Landau theory, we calculate the helicity moduli of each phase
to estimate the Kosterlitz-Thouless (KT) transition temperatures. Then at the
KT temperatures, we estimate the barriers to move vortices and effects that
lift the large degeneracy in the possible $\psi$ patterns. The effects we have
considered are inductive couplings, non-zero wire width, and the
order-by-disorder effect due to thermal fluctuations. The first two effects
prefer $q=0$ patterns while the last one selects a $\sqrt{3}\times\sqrt{3}$
pattern of supercurrents. Using the parameters of recent experiments, we
conclude that at the KT temperature, the non-zero wire width effect dominates,
which stabilizes a conventional superconducting phase with a $q=0$ current
pattern. However, by adjusting the experimental parameters, for example by
bending the wires a little, it appears that the novel $\psi^3$ superconducting
phase can instead be stabilized. The barriers to vortex motion are low enough
that the system can equilibrate into this phase.

</DOC>
<DOC>
<DOCNO> 99667 </DOCNO>
The resolvent for Laplace-type operators on asymptotically conic spaces


  Let X be a compact manifold with boundary, and g a scattering metric on X,
which may be either of short range or `gravitational' long range type. Thus, g
gives X the geometric structure of a complete manifold with an asymptotically
conic end. Let H be an operator of the form $H = \Delta + P$, where $\Delta$ is
the Laplacian with respect to g and P is a self-adjoint first order scattering
differential operator with coefficients vanishing at the boundary of X and
satisfying a `gravitational' condition. We define a symbol calculus for
Legendre distributions on manifolds with codimension two corners and use it to
give a direct construction of the resolvent kernel of H, $R(\sigma + i0)$, for
$\sigma$ on the positive real axis. In this approach, we do not use the
limiting absorption principle at any stage; instead we construct a parametrix
which solves the resolvent equation up to a compact error term and then use
Fredholm theory to remove the error term.

</DOC>
<DOC>
<DOCNO> 120306 </DOCNO>
Supermassive Black Holes in Disk Galaxies


  Dynamical searches find central dark objects - candidate supermassive black
holes (BHs) - in at least 34 galaxies. The demographics of these objects lead
to the following conclusions: (1) BH mass correlates with the luminosity of the
bulge component of the host galaxy, albeit with considerable scatter. The
median BH mass fraction is 0.15 % of the mass of the bulge. The quartiles are
0.09 % and 0.7 %. (2) BH mass correlates with the mean velocity dispersion of
the bulge component inside its effective radius, i.e., with how strongly the
bulge stars are gravitationally bound to each other. For the best BH mass
determinations, the scatter is consistent with the measurement errors. (3) BH
mass correlates with the luminosity of the high-density central component in
disk galaxies independent of whether this is a real bulge (a mini-elliptical)
or a "pseudobulge" (believed to form via inward transport of disk material).
(4) BH mass does not correlate with the luminosity of galaxy disks. If pure
disks contain BHs (and observations of active nuclei argue that some do), then
their BH mass fractions are much smaller than the canonical 0.15 % for bulges.
  These results lead to the following conclusions: (A) Present observations
show no dependence of BH mass on the details of whether BH feeding happens
rapidly during a collapse or slowly via secular evolution of the disk. (B) The
above results increasingly support the hypothesis that the major events that
form a bulge or elliptical galaxy and the main growth phases of its BH -- when
it shone as an active nucleus -- were the same events.

</DOC>
<DOC>
<DOCNO> 122289 </DOCNO>
Fast magnetic reconnection in free space: self-similar evolution process


  We present a new model for time evolution of fast magnetic reconnection in
free space, which is characterized by self-similarity. Reconnection triggered
by locally enhanced resistivity assumed at the center of the current sheet can
self-similarly and unlimitedly evolve until external factors affect the
evolution. The possibility and stability of this type of evolution are verified
by numerical simulations in a very wide spatial dynamic range. Actual
astrophysical reconnection in solar flares and geomagnetospheric substorms can
be treated as an evolutionary process in free space, because the resultant
scale is much larger than the initial scale. In spite of this fact, most of the
previous numerical works focused on the evolutionary characters strongly
affected by artificial boundary conditions on the simulation boundary. Our new
model clarifies a realistic evolution for such cases. The characteristic
structure around the diffusion region is quite similar to the Petschek model
which is characterized by a pair of slow-mode shocks and the fast-mode
rarefaction-dominated inflow. However, in the outer region, a vortex-like
return flow driven by the fast-mode compression caused by the piston effect of
the plasmoid takes place. The entire reconnection system expands
self-similarly.

</DOC>
<DOC>
<DOCNO> 123047 </DOCNO>
Sheared helical turbulence and the helicity constraint in large-scale


  The effect of shear on the growth of large scale magnetic fields in helical
turbulence is investigated. The resulting large-scale magnetic field is also
helical and continues to evolve, after saturation of the small scale field, on
a slow resistive time scale. This is a consequence of magnetic helicity
conservation. Because of shear, the time scale needed to reach an
equipartition-strength large scale field is shortened proportionally to the
ratio of the resulting toroidal to poloidal large scale fields.

</DOC>
<DOC>
<DOCNO> 39872 </DOCNO>
Linear Collider Signal of a Wino LSP in Anomaly Mediated Scenarios


  Selectron (smuon) pair-production in a next generation Linear Collider,
yielding a fast electron (muon) trigger, a visible heavily ionizing track
and/or a resolved soft pion impact parameter and overall $\mET$, is shown to
provide a smoking gun signature for Anomaly Mediated Supersymmetry Breaking
models with a neutral Wino as the Lightest Supersymmetric Particle, nearly
mass-degenerate with the lighter chargino.

</DOC>
<DOC>
<DOCNO> 116582 </DOCNO>
Suppression of Supercontinuum Generation with Circularly Polarized Light


  Controlling a nonlinear process like supercontinuum generation (SG) with the
polarization-state of laser is an important demonstration of laser selectivity.
We show that the threshold for SG and the total amount of supercontinuum
generated depends on incident laser polarization for isotropic samples.
Irrespective of the nature of the samples chosen, SG efficiency decreases as
the incident laser polarization changes from linear to circular and thus,
provides the first experimental demonstration of the suppression of SG with
circularly polarized light. The ratio of the overall SG between the linear and
circular polarization (i.e., measure of suppression) undergoes an intensity
dependent decrease from large initial values to asymptotic limits, irrespective
of samples.

</DOC>
<DOC>
<DOCNO> 84165 </DOCNO>
Topological Defects in 3-d Euclidean Gravity


  By making use of the complete decomposition of SO(3) spin connection, the
topological defect in 3-dimensional Euclidean gravity is studied in detail. The
topological structure of disclination is given as the combination of a monopole
structure and a vortex structure. Furthermore, the Kac-Moody algebra generated
by the monopole and vortex is discussed in three dimensional Chern-Simons
theory.

</DOC>
<DOC>
<DOCNO> 152101 </DOCNO>
Holographic Vacuum Energy


  Gravitational holography is argued to render the cosmological constant stable
against divergent quantum corrections. This provides a technically natural
solution to the cosmological constant problem. A natural solution can follow
from a symmetry of the action. Evidence for quantum stability of the
cosmological constant is illustrated in a number of examples including, bulk
descriptions in terms of delocalized degrees of freedom, boundary screen
descriptions on stretched horizons, and non-supersymmetric conformal field
theories as dual descriptions of anti-de Sitter space. In an expanding
universe, holographic quantum contributions to the stress-energy tensor are
argued to be at most of order the energy density of the dominant matter
component.

</DOC>
<DOC>
<DOCNO> 121647 </DOCNO>
Dependence of Gas Phase Abundances in the ISM on Column Density


  Sightlines through high- and intermediate-velocity clouds allow measurements
of ionic gas phase abundances, A, at very low values of HI column density,
N(HI). Present observations cover over 4 orders of magnitude in N(HI).
Remarkably, for several ions we find that the A vs N(HI) relation is the same
at high and low column density and that the abundances have a relatively low
dispersion (factors of 2-3) at any particular N(HI). Halo gas tends to have
slightly higher values of A than disk gas at the same N(HI), suggesting that
part of the dispersion may be attributed to the environment. We note that the
dispersion is largest for NaI; using NaI as a predictor of N(HI) can lead to
large errors. Important implications of the low dispersions regarding the
physical nature of the ISM are: (a) because of clumping, over sufficiently long
pathlengths N(HI) is a reasonable measure of the_local_ density of_most_ of the
H atoms along the sight line; (b) the destruction of grains does not mainly
take place in catastrophic events such as strong shocks, but is a continuous
function of the mean density; (c) the cycling of the ions becoming attached to
grains and being detached must be rapid, and the two rates must be roughly
equal under a wide variety of conditions; (d) in gas that has a low average
density the attachment should occur within denser concentrations.

</DOC>
<DOC>
<DOCNO> 71704 </DOCNO>
Trouble in Asymptopia---the Hulthen Model on the Light Front


  We use light-front dynamics to calculate the electromagnetic form-factor for
the Hulthen model of the deuteron. For small momentum transfer Q^2 < 5 GeV^2
the relativistic effects are quite small. For Q^2 = 11 GeV^2 there is about a
13% discrepancy between the relativistic and non-relativistic approaches. For
asymptotically large momentum transfer, however, the light-front form factor,
log Q^2 /Q^4, markedly differs from the non-relativistic version, 1/Q^4. This
behavior is also present for any wave function, such as those obtained from
realistic potential models, which can be represented as a sum of Yukawa
functions. Furthermore, the asymptotic behavior is in disagreement with the
Drell-Yan-West relation. We investigate precisely how to determine the
asymptotic behavior and confront the problem underlying troublesome form
factors on the light front.

</DOC>
<DOC>
<DOCNO> 99819 </DOCNO>
Experimental detection of interactive phenomena and their analysis


  The article is devoted to mathematical methods of experimental detection of
interactive phenomena in complex systems and their analysis.

</DOC>
<DOC>
<DOCNO> 121880 </DOCNO>
Wind Interaction Models for the Afterglows of GRB 991208 and GRB 000301C


  The simplest model of the afterglows of the gamma-ray bursts (GRBs) envisions
a spherical blast wave with a power-law distribution of electron energy above
some cutoff running into a constant density medium. A refinement involves a
narrow jet, often invoked to explain the steep decline and/or steepening of
light curves observed in some afterglows. The constant (ambient) density jet
model has been applied to GRBs 991208 and 000301C, based to a large extent on
radio observations. We show that, for these two sources, a spherical wind model
(with an $r^{-2}$ density ambient medium) can fit the radio data as well as the
jet model. %%We demonstrate that the The relatively steep decline and the
fairly abrupt steepening of the R-band light curves of, respectively, GRB
991208 and GRB 000301C can be accounted for with a non-standard, broken
power-law distribution of electron energy. Our model predicts a slower late
decline for the radio flux than does the jet model.

</DOC>
<DOC>
<DOCNO> 118884 </DOCNO>
Grad-Shafranov equation with anisotropic pressure


  The most general form of the nonrelativistic Grad-Shafranov equation
describing anisotropic pressure effects is formulated within the double
adiabatic approximation. It gives a possibility to analyze quantitatively how
the anisotropic pressure affects the 2D structure of the ideal
magnetohydrodynamical flows.

</DOC>
<DOC>
<DOCNO> 99460 </DOCNO>
Derivation-Simple Algebras and the Structures of Generalized Lie


  We classify all the pairs of a commutative associative algebra with an
identity element and its finite-dimensional commutative locally-finite
derivation subalgebra such that the commutative associative algebra is
derivation-simple with respect to the derivation subalgebra over an
algebraically closed field with characteristic 0. Such pairs are the
fundamental ingredients for constructing generalized simple Lie algebras of
Cartan type. Moreover, we determine the isomorphic classes of the generalized
simple Lie algebras of Witt Type. The structure space of these algebras is
given explicitly.

</DOC>
<DOC>
<DOCNO> 151631 </DOCNO>
Noncommutative Field Theory from String Theory: Two-loop Analysis


  Noncommutative \phi^3 field theory in six dimensions exhibits the logarithmic
UV/IR mixing at the two-loop order. We show that open string theory in the
presence of constant background NS-NS two-form field yields the same amplitude
upon taking a decoupling limit. The stretched string picture proposed on the
basis of one-loop analysis naturally generalizes to the two-loop amplitudes in
consideration. Our string theory formulation can incorporate the closed string
insertions as well as open string insertions. Furthermore, the analysis of the
world-sheet partition function and propagators can be straightforwardly
generalized to Riemann surfaces with genus zero but with an arbitrary number of
boundaries.

</DOC>
<DOC>
<DOCNO> 116273 </DOCNO>
Nonlinear denoising of transient signals with application to event


  We present a new wavelet based method for the denoising of {\it event related
potentials} ERPs), employing techniques recently developed for the paradigm of
deterministic chaotic systems. The denoising scheme has been constructed to be
appropriate for short and transient time sequences using circular state space
embedding. Its effectiveness was successfully tested on simulated signals as
well as on ERPs recorded from within a human brain. The method enables the
study of individual ERPs against strong ongoing brain electrical activity.

</DOC>
<DOC>
<DOCNO> 119387 </DOCNO>
On the Nature of Andromeda IV


  Lying at a projected distance of 40' or 9 kpc from the centre of M31,
Andromeda IV is an enigmatic object first discovered during van den Bergh's
search for dwarf spheroidal companions to M31. Being bluer, more compact and
higher surface brightness than other known dwarf spheroidals, it has been
suggested that And IV is either a relatively old `star cloud' in the outer disk
of M31 or a background dwarf galaxy. We present deep HST WFPC2 observations of
And IV and the surrounding field which, along with ground-based long-slit
spectroscopy and Halpha imagery, are used to decipher the true nature of this
puzzling object. We find compelling evidence that And IV is a background galaxy
seen through the disk of M31. The moderate surface brightness (SB(V)~24), very
blue colour (V-I<~0.6), low current star formation rate (~0.001 solar mass/yr)
and low metallicity (~10% solar) reported here are consistent with And IV being
a small dwarf irregular galaxy, perhaps similar to Local Group dwarfs such as
IC 1613 and Sextans A. Although the distance to And IV is not tightly
constrained with the current dataset, various arguments suggest it lies in the
range 5<~D<~8 Mpc, placing it well outside the confines of the Local Group. It
may be associated with a loose group of galaxies, containing major members UGC
64, IC 1727 and NGC 784. We report an updated position and radial velocity for
And IV.

</DOC>
<DOC>
<DOCNO> 40147 </DOCNO>
Role of Group and Phase Velocity in High-Energy Neutrino Observatories


  Kuzmichev recently showed that use of phase velocity rather than group
velocity for Cherenkov light signals and pulses from calibration lasers in
high-energy neutrino telescopes leads to errors in track reconstruction and
distance measurement. We amplify on his remarks and show that errors for four
cases of interest to AMANDA, IceCube, and RICE (radio Cherenkov detector) are
negligibly small.

</DOC>
<DOC>
<DOCNO> 12763 </DOCNO>
Magnetic Collective Mode Dispersion in High Temperature Superconductors


  Recent neutron scattering experiments in the superconducting state of YBCO
have been interpreted in terms of a magnetic collective mode whose dispersion
relative to the commensurate wavevector has a curvature opposite in sign to a
conventional magnon dispersion. The purpose of this article is to demonstrate
that simple linear response calculations are in support of a collective mode
interpretation, and to explain why the dispersion has the curvature it does.

</DOC>
<DOC>
<DOCNO> 101733 </DOCNO>
The non-self-adjointness of the radial momentum operator in n dimensions


  The non self-adjointness of the radial momentum operator has been noted
before by several authors, but the various proofs are incorrect. We give a
rigorous proof that the $n$-dimensional radial momentum operator is not self-
adjoint and has no self-adjoint extensions. The main idea of the proof is to
show that this operator is unitarily equivalent to the momentum operator on
$L^{2}[(0,\infty),dr]$ which is not self-adjoint and has no self-adjoint
extensions.

</DOC>
<DOC>
<DOCNO> 120159 </DOCNO>
Type Ia supernova rate at $z \sim 0.1$


  We present the EROS nearby supernova ($z \sim 0.02 - 0.2$) search and the
analysis of the first year of data (1997). A total of 80 square degrees were
surveyed. Eight supernov{\ae} were detected, four of which were
spectroscopically identified as type Ia supernov{\ae}. The search efficiency
was determined with a Monte-Carlo simulation taking into account the
efficiencies for both supernova detection and host galaxy identification.
Assuming that for a given galaxy the supernova rate is proportional to the
galactic luminosity, we compute a type Ia supernova explosion rate of:
  ${\cal R} = 0.44 {}_{-0.21}^{+0.35} {}_{-0.07}^{+0.13} h^2: / 10^{10}
  \lbsun / 100 {\rm yrs}$ at an average redshift of $\sim 0.1$ where the errors
are respectively statistical and systematic (type misidentification included).

</DOC>
<DOC>
<DOCNO> 117000 </DOCNO>
Structural Analysis of Superconducting Accelerator Cavities


  The static and dynamic structural behavior of superconducting cavities for
various projects was determined by finite element structural analysis. The b =
0.61 cavity shape for the Neutron Science Project was studied in detail and
found to meet all design requirements if fabricated from five millimeter thick
material with a single annular stiffener. This 600 MHz cavity will have a
Lorentz coefficient of -1.8 Hz/(Mv/meter)2 and a lowest structural resonance of
more than 100 Hz. Cavities at b = 0.48, 0.61, and 0.77 were analyzed for a
Neutron Science Project concept which would incorporate 7-cell cavities. The
medium and high beta cavities were found to meet all criteria but it was not
possible to generate a b = 0.48 cavity with a Lorentz coefficient of less than
-3 Hz/(Mv/meter) 2.

</DOC>
<DOC>
<DOCNO> 8159 </DOCNO>
Crystal-like high frequency phonons in the amorphous phases of solid


  The high frequency dynamics of low- (LDA) and high-density amorphous-ice
(HDA) and of cubic ice (I_c) has been measured by inelastic X-ray Scattering
(IXS) in the 1-15 nm^{-1} momentum transfer (Q) range. Sharp phonon-like
excitations are observed, and the longitudinal acoustic branch is identified up
to Q = 8nm^{-1} in LDA and I_c and up to 5nm^{-1} in HDA. The narrow width of
these excitations is in sharp contrast with the broad features observed in all
amorphous systems studied so far. The "crystal-like" behavior of amorphous
ices, therefore, implies a considerable reduction in the number of decay
channels available to sound-like excitations which is assimilated to low local
disorder.

</DOC>
<DOC>
<DOCNO> 12195 </DOCNO>
One way to Characterize the compact structures of lattice protein model


  On the study of protein folding, our understanding about the protein
structures is limited. In this paper we find one way to characterize the
compact structures of lattice protein model. A quantity called Partnum is given
to each compact structure. The Partnum is compared with the concept
Designability of protein structures emerged recently. It is shown that the
highly designable structures have, on average, an atypical number of local
degree of freedom. The statistical property of Partnum and its dependence on
sequence length is also studied.

</DOC>
<DOC>
<DOCNO> 84238 </DOCNO>
Acceleration and Special Relativity


  The integration of acceleration over time before reaching the uniform
velocity turns out to be the source of all the special relativity effects. It
explains physical phenomena like clocks comparisons. The equations for
space-time, mass and energy are presented. This phenomenon complements the
explanation for the twins paradox. A Universal reference frame is obtained.

</DOC>
<DOC>
<DOCNO> 72220 </DOCNO>
Type I Strings with F- and B-Flux


  We present non-supersymmetric toroidal compactifications of type I string
theory with both constant background NSNS two-form flux and non-trivial
magnetic flux on the various D9-branes. The non-vanishing B-flux admits
four-dimensional models with three generations of chiral fermions in standard
model like gauge groups. Additionally, we consider the orbifold T^4/Z_2, again
with both kinds of background flux present, leading to non-supersymmetric as
well as supersymmetric models in six dimensions. All models have T-dual
descriptions as intersecting brane worlds.

</DOC>
<DOC>
<DOCNO> 118670 </DOCNO>
Fourier power spectra at high frequencies: a way to distinguish a


  We analyzed the power density spectra of a sample of 9 neutron star and 9
black hole binaries in the low/hard spectral state. In the power density
spectra of accreting neutron stars with a weak magnetic field a significant
power is contained at frequencies close to one kHz. At the same time, most
Galactic accreting black holes demonstrate a strong decline in the power
spectra at the frequencies higher than 10--50 Hz. We propose to use this
empirical fact as a method to distinguish the accreting neutron stars from
black holes in X-ray transients. The X-ray transients that demonstrate
significant noise in their X-ray flux at frequencies above ~500 Hz should be
considered neutron stars. We propose to explain the observed difference as a
result of the existence of a radiation dominated spreading layer on the neutron
star surface (Inogamov & Sunyaev 1999). The possible very high frequency
variabilities of this layer are discussed.

</DOC>
<DOC>
<DOCNO> 69997 </DOCNO>
Variations on the Deuteron


  We consider few problems which are related to the deuteron and have simple
analytical solution. Relation is found between the deuteron electric quadrupole
moment and the $np$-scattering amplitude. The degree of circular polarization
of photons is calculated for the radiative capture of longitudinally polarized
thermal neutrons. The anapole, electric dipole and magnetic quadrupole moments
of the deuteron are calculated.

</DOC>
<DOC>
<DOCNO> 83466 </DOCNO>
Termination analysis of logic programs using acceptability with general


  We present a new approach to termination analysis of logic programs. The
essence of the approach is that we make use of general term-orderings (instead
of level mappings), like it is done in transformational approaches to logic
program termination analysis, but that we apply these orderings directly to the
logic program and not to the term-rewrite system obtained through some
transformation. We define some variants of acceptability, based on general
term-orderings, and show how they are equivalent to LD-termination. We develop
a demand driven, constraint-based approach to verify these
acceptability-variants.
  The advantage of the approach over standard acceptability is that in some
cases, where complex level mappings are needed, fairly simple term-orderings
may be easily generated. The advantage over transformational approaches is that
it avoids the transformation step all together.

</DOC>
<DOC>
<DOCNO> 13795 </DOCNO>
Coexistence of Superconductivity and Antiferromagnetism in Heavy-Fermion


  We report on the basis of Cu-NQR measurements that superconductivity (SC) and
antiferromagnetism (AF) coexist on a microscopic level in
CeCu_{2}(Si_{1-x}Ge_{x})_{2}, once a tiny amount of 1%Ge (x = 0.01) is
substituted for Si. This coexistence arises because Ge substitution expands the
unit-cell volume in nearly homogeneous CeCu2Si2 where the SC coexists with
slowly fluctuating magnetic waves. We propose that the underlying exotic phases
of SC and AF in either nearly homogeneous or slightly Ge substituted CeCu2Si2
are accountable based on the SO(5) theory that unifies the SC and AF. We
suggest that the mechanism of the SC and AF is common in CeCu2Si2.

</DOC>
<DOC>
<DOCNO> 117071 </DOCNO>
Has superluminal light propagation been observed?


  It says in the report$^1$ by Wang et al. that a negative group velocity
$u=-c/310$ is obtained and that a pulse advancement shift 62-ns is measured.
The authors claim that the negative group velocity is associated with
superluminal light propagation and that the pulse advancement is not at odds
with causality or special relativity. However, it is shown here that their
conclusions above are not true. Furthermore, I give some suggestion concerning
a re-definition of group-velocity and a new explanation in special relativity
of causality.

</DOC>
<DOC>
<DOCNO> 121398 </DOCNO>
Weak Lensing Predictions at Intermediate Scales


  As pointed out in previous studies, the measurement of the skewness of the
convergence field $\kappa$ will be useful in breaking the degeneracy among the
cosmological parameters constrained from weak lensing observations. The
combination of shot noise and finite survey volume implies that such a
measurement is likely to be done in a range of intermediate scales ($0.5'$ to
20') where neither perturbation theory nor the hierarchical ansatz apply. Here
we explore the behavior of the skewness of $\kappa$ at these intermediate
scales, based on results for the non-linear evolution of the mass bispectrum.
We combined different ray-tracing simulations to test our predictions, and we
find that our calculations describe accurately the transition from the weakly
non-linear to the strongly non-linear regime. We show that the single
lens-plane approximation remains accurate even in the non-linear regime, and we
explicitly calculate the corrections to this approximation. We also discuss the
prospects of measuring the skewness in upcoming weak lensing surveys.

</DOC>
<DOC>
<DOCNO> 11475 </DOCNO>
A nonlinear hydrodynamical approach to granular materials


  We propose a nonlinear hydrodynamical model of granular materials. We show
how this model describes the formation of a sand pile from a homogeneous
distribution of material under gravity, and then discuss a simulation of a
rotating sandpile which shows, in qualitative agreement with experiment, a
static and dynamic angle of repose.

</DOC>
<DOC>
<DOCNO> 150907 </DOCNO>
Soldering and Mass Generation in Four Dimensions


  We propose bosonised expressions for the chiral Schwinger models in four
dimensions. Then, in complete analogy with the two dimensional case, we show
the soldering of two bosonised chiral Schwinger models with opposite
chiralities to yield the bosonised Schwinger model in four dimensions. The
implications of the Schwinger model or its chiral version, as known for two
dimensions, thereby get extended to four dimensions.

</DOC>
<DOC>
<DOCNO> 100173 </DOCNO>
A small transitive family of continuous functions on the Cantor set


  In this paper we show that, when we iteratively add Sacks reals to a model of
ZFC we have for every two reals in the extension a continuous function defined
in the ground model that maps one of the reals onto the other.

</DOC>
<DOC>
<DOCNO> 123245 </DOCNO>
New Evidence for Black Hole Event Horizons from Chandra


  Previously we claimed that Black Hole X-ray Novae (BHXN) in quiescence are
much less luminous than equivalent Neutron Star X-ray Novae (NSXN). This claim
was based on the quiescent detection of a single short period BHXN (A0620-00,
P(orb)=7.8 hrs) and two longer period BHXN (GRO J1655-40, P(orb)=62.9 hrs; V404
Cyg, P(orb)=155.3 hrs), along with sensitive upper limits. We announce the
detection of two more short period BHXN (GRO J0422+32, P(orb)=5.1 hrs; GS
2000+25, P(orb)=8.3 hrs), an upper limit for a third which is improved by two
orders of magnitude (4U 1543-47, P(orb)=27.0 hrs) and a new, much lower
quiescent measurement of GRO J1655-40. Taken together, these new Chandra
measurements confirm that the quiescent X-ray luminosities of BHXN are
significantly lower than those of NSXN. We argue that this provides strong
evidence for the existence of event horizons in BHXN.

</DOC>
<DOC>
<DOCNO> 70322 </DOCNO>
Low-Scale and Gauge-Mediated Supersymmetry Breaking at the Fermilab


  The prospects for discovering and studying signals of low-scale supersymmetry
breaking models at the Tevatron Run II and beyond are explored. These models
include gauge-mediated supersymmetry breaking as the most compelling and
concrete realization, but more generally are distinguished by the presence of a
nearly massless Goldstino as the lightest supersymmetric particle. The
next-lightest supersymmetric particle(s) (NLSP) decays to its partner and the
Goldstino. Depending on the supersymmetry breaking scale, these decays can
occur promptly or on a scale comparable to or larger than the size of a
detector. A systematic analysis based on a classification in terms of the
identity of the NLSP and its decay length is presented. The various scenarios
are discussed in terms of signatures and possible event selection criteria. The
Run II and beyond discovery and exclusion reaches, including the effects of
background, are detailed for the most compelling cases. In addition to standard
event selection criteria based on missing energy and photons, leptons, jets,
taus, tagged b-jets, or reconstructed Z-bosons, more exotic signals of
metastable NLSPs such as displaced photons, large negative impact parameter
tracks, kink tracks, both opposite and same-sign highly ionizing tracks, time
of flight measurements, charge-changing tracks, charge-exchange tracks, and
same-sign di-top events are investigated. The interesting possibility of
observing a Higgs boson signal in events that are efficiently "tagged" by the
unique signatures of low-scale supersymmetry breaking is also considered.

</DOC>
<DOC>
<DOCNO> 8638 </DOCNO>
Creep and depinning in disordered media


  Elastic systems driven in a disordered medium exhibit a depinning transition
at zero temperature and a creep regime at finite temperature and slow drive
$f$. We derive functional renormalization group equations which allow to
describe in details the properties of the slowly moving states in both cases.
Since they hold at finite velocity $v$, they allow to remedy some shortcomings
of the previous approaches to zero temperature depinning. In particular, they
enable us to derive the depinning law directly from the equation of motion,
with no artificial prescription or additional physical assumptions. Our
approach provides a controlled framework to establish under which conditions
the depinning regime is universal. It explicitly demonstrates that the random
potential seen by a moving extended system evolves at large scale to a random
field and yields a self-contained picture for the size of the avalanches
associated with the deterministic motion. At $T>0$ we find that the effective
barriers grow with lenghtscale as the energy differences between neighboring
metastable states, and demonstrate the resulting activated creep law $v\sim
\exp (-C f^{-\mu}/T)$ where the exponent $\mu$ is obtained in a $\epsilon=4-D$
expansion ($D$ is the internal dimension of the interface). Our approach also
provides quantitatively a new scenario for creep motion as it allows to
identify several intermediate lengthscales. In particular, we unveil a novel
``depinning-like'' regime at scales larger than the activation scale, with
avalanches spreading from the thermal nucleus scale up to the much larger
correlation length $R_{V}$. We predict that $R_{V}\sim T^{-\sigma}f^{-\lambda
}$ diverges at small $f$ and $T$ with exponents $\sigma ,\lambda$ that we
determine.

</DOC>
<DOC>
<DOCNO> 117905 </DOCNO>
Discovery of a Color-Selected Quasar at z=5.50


  We present observations of RD J030117+002025, a quasar at z=5.50 discovered
from deep, multi-color, ground-based observations covering 74 square arcmin.
This is the most distant quasar or AGN currently known. The object was targeted
as an R-band dropout, with R(AB)>26.3 (3-sigma limit in a 3 arcsec diameter
region), I(AB)=23.8, and z(AB)=23.4. The Keck/LRIS spectrum shows broad
Lyman-alpha/NV emission and sharp absorption decrements from the
highly-redshifted hydrogen forests. The fractional continuum depression due to
the Lyman-alpha forest is D(A)=0.90. RD J030117+002025 is the least luminous,
high-redshift quasar known (M(B)~-22.7).

</DOC>
<DOC>
<DOCNO> 9171 </DOCNO>
Macroscopic quantum self-trapping and atomic tunneling in two-species


  We present a new theoretical treatment of macroscopic quantum self-trapping
(MQST) and quantum coherent atomic tunneling in a zero-temperature two-species
Bose-Einstein condensate system in the presence of the nonlinear
self-interaction of each species, the interspecies nonlinear interaction, and
the Josephson-like tunneling interaction. It is shown that the nonlinear
interactions can dramatically affect the MQST and the atomic tunneling, and
lead to the collapses and revivals (CR) of population imbalance between the two
condensates. The competing effects between the self-interaction of each species
and the interspecies interaction can lead to the quenching of the MQST and the
suppression of the CR and the Shapiro-like steps of the atomic tunneling
current. It is revealed that the interatomic nonlinear interactions can induce
the coherent atomic tunneling between two condensates even though there does
not exist the interspecies
 Josephson-like tunneling coupling.

</DOC>
<DOC>
<DOCNO> 13434 </DOCNO>
Probability density of determinants of random matrices


  In this brief paper the probability density of a random real, complex and
quaternion determinant is rederived using singular values. The behaviour of
suitably rescaled random determinants is studied in the limit of infinite order
of the matrices.

</DOC>
<DOC>
<DOCNO> 85023 </DOCNO>
Extremal Black holes and the limits of the third law


  Recent results of quantum field theory on a curved spacetime suggest that
extremal black holes are not thermal objects and that the notion of zero
temperature is ill-defined for them. If this is correct, one may have to go to
a full semiclassical theory of gravity, including backreaction, in order to
make sense of the third law of black hole thermodynamics. Alternatively, it is
possible that we shall have to drastically revise the status of extremality in
black hole thermodynamics.

</DOC>
<DOC>
<DOCNO> 116928 </DOCNO>
The RF-System of the New Gsi High Current Linac Hsithe RF-System of the


  The RF part of the new high current injector-linac HSI consists of five
cavities with the new operating frequency of 36 MHz instead of 27 MHz of the
removed Wideroe type injector. The calculated power requirements of the
cavities including beam load in three structures were between 110 kW for a
rebuncher and 1.75 MW pulse-power for the two IH-cavities. The beam load is up
to 150 kW for the RFQ and up to 750 kW for the two drift tube tanks. An
additional 36 MHz debuncher in the transfer line to the Synchrotron (SIS) will
need 120 kW pulse power. We decided to fulfil these demands with amplifiers of
only two power classes, namely three amplifiers with 2 MW and six amplifiers
with 200 kW pulse output power. The latter ones are also used as drivers for
the 2 MW stages. The 200 kW amplifiers were specified in detail by GSI and
ordered in the industry. The three 2 MW final amplifiers were designed,
constructed and built by GSI. The paper gives an overview of the complete RF
system and the operating performance of amplitude and phase control with beam
load. It further describes some specialities of the new 2 MW amplifiers like
the simplicity of the anode circuit, a very sophisticated socket for a cathode
driven amplifier with cathode on dc ground, the parasitic mode-suppression,
shielding and filtering of unallowable RF-radiation and operating experience
since October 1999.

</DOC>
<DOC>
<DOCNO> 12423 </DOCNO>
Is There a Phase Transition in the Isotropic Heisenberg Antiferromagnet


  The phase diagram of the classical anisotropic (XXZ) Heisenberg model on the
2-dimensional triangular lattice is investigated using Monte Carlo methods. In
the easy-axis limit, two finite temperature vortex unbinding transitions have
been observed. In the easy-plane limit, there also appear to be two distinct
finite temperature phase transitions. The upper transition corresponds to an
Ising-like chirality ordering and the lower temperature transition corresponds
to a Kosterlitz-Thouless vortex unbinding transition. These phase transition
lines all meet at the Heisenberg point and provide strong evidence that the
isotropic model undergoes a novel finite temperature phase transition.

</DOC>
<DOC>
<DOCNO> 71851 </DOCNO>
A new bigravity model with exclusively positive branes


  We propose a new ``bigravity'' model with two positive tension AdS_4 branes
in AdS_5 bulk and no negative tension branes. The bounce of the ``warp'' factor
mimics the effect of a negative brane and thus gives rise to an anomalously
light graviton KK mode. This configuration satisfies the weak energy condition
and has no ghost state. In addition, the extra polarization states of the
massive graviton practically decouple and thus it does not contradict to
Einsteinian gravity. However, the model has certain phenomenological
difficulties associated with the presence of a negative cosmological constant
on the branes.

</DOC>
<DOC>
<DOCNO> 8851 </DOCNO>
Effect of Quantised Lattice Fluctuations on the Electronic States of


  We solve a model of interacting electrons coupled to longitudinal phonons
using the density matrix renormalisation group method. The model is
parametrised for polyenes. We calculate the ground state, and first excited
odd-parity singlet and triplet states; and we investigate their energies, and
bond length changes and fluctuations for up to 30 sites. The transition energy
and the soliton width of the triplet state show deviations from the adiabatic
approximation for chain lengths larger than the classical soliton size, because
of de-pinning by the quantised lattice fluctuations.

</DOC>
<DOC>
<DOCNO> 169741 </DOCNO>
Separability properties of tripartite states with UxUxU-symmetry


  We study separability properties in a 5-dimensional set of states of quantum
systems composed of three subsystems of equal but arbitrary finite Hilbert
space dimension. These are the states, which can be written as linear
combinations of permutation operators, or, equivalently, commute with unitaries
of the form UxUxU. We compute explicitly the following subsets: (1)
triseparable states, which are convex combinations of triple tensor products,
(2) biseparable states, which are separable for a twofold partition of the
system, and (3) states with positive partial transpose with respect to such a
partition.

</DOC>
<DOC>
<DOCNO> 12936 </DOCNO>
One-dimensional Surface Bound States in d-wave Superconductors


  We present an {\it exact} quantum theory for the bound states in the vicinity
of an edge or a line of impurities in a $d_{x^2-y^2}$ superconductor. For a
(110)-surface we show that a finite dispersion of the one dimensional band of
bound states leads to a two peak structure in the density of states (DOS). We
study the effect of an applied magnetic field and a subdominant $id_{xy}$ order
parameter on the DOS and discuss the implications of our results for tunneling
experiments.

</DOC>
<DOC>
<DOCNO> 12416 </DOCNO>
Disorder induced roughening transition of many elastic lines in a


  The competing effect of a periodic pinning potential and random point
disorder is studied for arrays of elastic lines or directed polymers. The
groundstates are investigated by exact combinatorial optimization. In both two
and three dimensions a phase diagram is found with two or three distinct
phases: a strictly flat phase if the disorder is bounded and weak, a weakly
fluctuating phase for intermediate valleys depths, where the lines roughen
individually on a scale smaller than the line-line distance, and a rough phase
for strong disorder, where the roughness follows the scaling with pure point
disorder. The line wandering in the transverse direction leads in the
three-dimensional, rough phase to an entangled state with a complicated
topology.

</DOC>
<DOC>
<DOCNO> 151401 </DOCNO>
Parafermionic character formulae


  We study various aspects of parafermionic theories such as the precise field
content, a description of a basis of states (that is, the counting of
independent states in a freely generated highest-weight module) and the
explicit expression of the parafermionic singular vectors in completely
irreducible modules. This analysis culminates in the presentation of new
character formulae for the $Z_N$ parafermionic primary fields. These characters
provide novel field theoretical expressions for $\su(2)$ string functions.

</DOC>
<DOC>
<DOCNO> 101940 </DOCNO>
Special rays in the Mori cone of a projective variety


  Let $X$ be a smooth $n$-dimensional projective variety over an algebraically
closed field $k$ such that $K_X$ is not nef. We give a characterization of non
nef extremal rays of $X$ of maximal length (i.e of length $n-1$); in the case
of $\ch(k) = 0$ we also characterize non nef rays of length $n-2$.

</DOC>
<DOC>
<DOCNO> 7698 </DOCNO>
Finite Size Scaling of Perceptron


  We study the first-order transition in the model of a simple perceptron with
continuous weights and large, bit finite value of the inputs. Making the
analogy with the usual finite-size physical systems, we calculate the shift and
the rounding exponents near the transition point. In the case of a general
perceptron with larger variety of inputs, the analysis only gives bounds for
the exponents.

</DOC>
<DOC>
<DOCNO> 13425 </DOCNO>
Dynamics and Scaling of Noise-Induced Domain Growth


  The domain growth processes originating from noise-induced nonequilibrium
phase transitions are analyzed, both for non-conserved and conserved dynamics.
The existence of a dynamical scaling regime is established in the two cases,
and the corresponding growth laws are determined. The resulting universal
dynamical scaling scenarios are those of Allen-Cahn and Lifshitz-Slyozov,
respectively. Additionally, the effect of noise sources on the behaviour of the
pair correlation function at short distances is studied.

</DOC>
<DOC>
<DOCNO> 69015 </DOCNO>
Electromagnetic and gravitational decay of the Higgs boson


  The decays of a scalar particle, of either parity, into two photons or into
two gravitons are evaluated. The effective interactions are of the form $\phi
FF, \phi F\tilde{F}$ or $\phi RR,\phi R\tilde{R}$; in particular, Higgs boson
decay into gravitons cannot be adduced to an interaction $\phi R$, as has been
recently claimed.

</DOC>
<DOC>
<DOCNO> 69291 </DOCNO>
Natural Mass Hierarchy of Z Boson and Scalar Top in No-Scale


  It is studied that `no-scale' model makes hierarchy between scalar top mass
and Z boson mass naturally. The supersymmetry breaking parameters are
constrained by flavor changing neutral currents in minimal supersymmetric
standard model. One of the solution of the problem is that gaugino mass is the
only source of the supersymmetry breaking parameters at Planck scale. However,
in such scenario, we need a cancellation between Higgs mass parameters in
minimization condition of the Higgs potential. We insist that there is no such
cancellation in no-scale model, and that the no-scale model gives us the
prediction of scalar top mass and lightest Higgs mass. The lightest Higgs mass
is predicted as $m_H = 110 \pm 5 $ GeV.

</DOC>
<DOC>
<DOCNO> 72190 </DOCNO>
Confinement as crossover


  The order parameter of confinement together with the haaron model of the QCD
vacuum is reviewed and it is pointed out that confining forces are generated by
the non-renormalizable, invariant Haar-measure vertices of the path integral. A
hybrid model is proposed for the description of the crossover leading to the
confining vacuum. This scenario suggests that the differences between the low
and the high temperature phases of QCD should be looked for in the quark
channels instead of the hadronic sector.

</DOC>
<DOC>
<DOCNO> 71785 </DOCNO>
Parton distributions in the chiral quark model: a continuum computation


  We compute the parton distributions for the chiral quark model. We present a
new technique for performing such computations based on Green functions. This
approach avoids a discretization of the spectrum. It therefore does not need
any smoothing procedures.
 The results are similar to those of other groups, however the distributions
peak at smaller $x$.

</DOC>
<DOC>
<DOCNO> 121235 </DOCNO>
Dynamical effects on galaxies in clusters


  The observed morphological evolution since z ~ 0.5 within galaxy clusters
provides evidence for a hierarchical universe. This evolution is driven by
dynamical effects that operate within the cluster environment -- suppression of
star-formation by ram-pressure and viscous stripping of the intra-galactic
medium and tidal heating of disks by gravitational encounters.

</DOC>
<DOC>
<DOCNO> 116922 </DOCNO>
Towards Reliable Acceleration of High-energy and High-intensity Electron


  KEK electron linac was upgraded to 8 GeV for the KEK B-Factory (KEKB)
project. During the commissioning of the upgraded linac, even continuing SOR
ring injections, we had achieved a primary electron beam with 10-nC (6.24 x
10^10) per bunch up to 3.7-GeV for positron generation. This could be
classified as one of the brightest S-band linac's.
 Since the KEKB rings were completed in December 1998, those 3.5-GeV position
and 8-GeV electron beams have been injected with an excellent performance.
Moreover, we have succeeded in switching among the high-intensity beams for
KEKB and beams for two SOR rings with sufficient reproducibility.
 After the commissioning of the KEKB ring started, we have launched a project
to stabilize the intensity and quality of the high-current beams furthermore,
and have accomplished it investigating every conceivable aspect.

</DOC>
<DOC>
<DOCNO> 151928 </DOCNO>
String Fluid from Unstable D-branes


  We consider Sen's effective action for unstable D-branes, and study its
classical dynamics exactly. In the true vacuum, the Hamiltonian dynamics
remains well-defined despite a vanishing action, and is that of massive
relativistic string fluid of freely moving electric flux lines. The
energy(tension) density equals the flux density in the local co-moving frame.
Furthermore, a finite dual Lagrangian exists and is related to the
Nielsen-Olesen field theory of ``dual'' strings, supplemented by a crucial
constraint. We conclude with discussion on the endpoint of tachyon
condensation.

</DOC>
<DOC>
<DOCNO> 117698 </DOCNO>
Atomic diffusion in metal poor stars. The influence on the Main Sequence


  The effect of atomic diffusion on the Main Sequence (MS) of metal-poor low
mass stars is investigated. Since diffusion alters the stellar surface chemical
abundances with respect to their initial values, one must ensure - by
calibrating the initial chemical composition of the theoretical models - that
the surface abundances of the models match the observed ones of the stellar
population under scrutiny. Since the observed surface abundances of subdwarfs
are different from the initial ones due to the effect of diffusion, while the
globular clusters stellar abundances are measured in Red Giants, which have
practically recovered their initial abundances after the dredge-up, the
isochrones to be employed for studying globular clusters and Halo subdwarfs
with the same observational value of [Fe/H] are different and do not coincide.
We find, however,that the current MS-fitting distances derived from HIPPARCOS
subdwarfs using colour corrections from standard isochrones are basically
unaltered when diffusion is taken properly into account; on the other hand, the
absolute ages, the age dispersion, the age-metallicity relation for Halo
subdwarfs, as well as the value of the helium enrichment ratio Delta Y/Delta Z
obtained from the width of the empirical Halo subdwarfs MS, are all
significantly modified when the properly calibrated isochrones with diffusion
are used.

</DOC>
<DOC>
<DOCNO> 151578 </DOCNO>
A Note on Non-Locality and Ostrogradski's Construction


  We consider the Hamiltonian treatment of non-local theories and
Ostrogradski's formalism. This has recently also been discussed by Woodard
(hep-th/0006207) and by Gomis, Kamimura and Llosa (hep-th/0006235). In our
approach we recast the second class constraints into first class constraints
and invoke the boundary Poisson bracket.

</DOC>
<DOC>
<DOCNO> 83445 </DOCNO>
Anonymous Oblivious Transfer


  In this short note we want to introduce {\em anonymous oblivious transfer} a
new cryptographic primitive which can be proven to be strictly more powerful
than oblivious transfer. We show that all functions can be robustly realized by
multi party protocols with {\em anonymous oblivious transfer}. No assumption
about possible collusions of cheaters or disruptors have to be made.
Furthermore we shortly discuss how to realize anonymous oblivious transfer with
oblivious broadcast or by quantum cryptography. The protocol of anonymous
oblivious transfer was inspired by a quantum protocol: the anonymous quantum
channel.

</DOC>
<DOC>
<DOCNO> 120626 </DOCNO>
KPD1930+2752 - a candidate Type Ia supernova progenitor


  We present spectra of the pulsating sdB star KPD1930+2752 which confirm that
this star is a binary. The radial velocities measured from the H-alpha and
HeI6678 spectral lines vary sinusoidally with the same period (2h 17m) as the
ellipsoidal variability seen by Billeres et al. (2000). The amplitude of the
orbital motion (349.3+-2.7 km/s) combined with the canonical mass for sdB stars
(0.5 solar masses) implies a total mass for the binary of 1.47+-0.01 solar
masses The unseen companion star is almost certainly a white dwarf star. The
binary will merge within about 200 million years due to gravitational wave
radiation. The accretion of helium and other elements heavier than hydrogen
onto the white dwarf which then exceeds the Chandrasekhar mass (1.4 solar
masses) is a viable model for the cause of Type Ia supernovae. KPD1930+2752 is
the first star to be discovered which is a good candidate for the progenitor of
a Type Ia supernova of this type which will merge on an astrophysically
interesting timescale.

</DOC>
<DOC>
<DOCNO> 69728 </DOCNO>
Momentum-dependent contributions to the gravitational coupling of


  When neutrinos travel through a normal matter medium, the electron neutrinos
couple differently to gravity compared to the other neutrinos, due to the
presence of electrons in the medium and the absence of the other charged
leptons. We calculate the momentum-dependent part of the matter-induced
gravitational couplings of the neutrinos under such conditions, which arise at
order $g^2/M^4_W$, and determine their contribution to the neutrino dispersion
relation in the presence of a gravitational potential $\phi^{\mathrm{ext}}$.
These new contributions vanish for the muon and tau neutrinos. For electron
neutrinos with momentum $K$, they are of the order of the usual Wolfenstein
term times the factor $(K^2/M^2_W)\phi^{\mathrm{ext}}$, for high energy
neutrinos. In environments where the gravitational potential is substantial,
such as those in the vicinity of Active Galactic Nuclei, they could be the
dominant term in the neutrino dispersion relation. They must also be taken into
account in the analysis of possible violations of the Equivalence Principle in
the neutrino sector, in experimental settings involving high energy neutrinos
traveling through a matter background.

</DOC>
<DOC>
<DOCNO> 150371 </DOCNO>
Dual generalizations of sine-Gordon field theory and integrability


  The dual relationship between two n-1 parameter families of quantum field
theories based on extended complex numbers is investigated in two dimensions.
The non-local conserved charges approach is used. The lowest rank affine Toda
field theories are generated and identified as integrability submanifolds in
parameter space. A truncation of the model leads to a conformal field theory in
extended complex space. Depending on the projection over usual complex space
chosen, a parametrized central charge is calculated.

</DOC>
<DOC>
<DOCNO> 84832 </DOCNO>
Assisted inflation in Friedmann-Robertson-Walker and Bianchi spacetimes


  We use exact general solutions for the spatially flat FRW and the anisotropic
Bianchi I cosmologies to show that generically uncoupled scalar fields
cooperate to make inflation more probable, while the presence of several
interacting fields hinders the occurrence of the phenomenon, in accordance with
previous results based on particular power-law solutions. Similar conclusions
are reached in the case of Bianchi VI$_0$ spacetimes, for power-law solutions
which are proved to be attractors.

</DOC>
<DOC>
<DOCNO> 169842 </DOCNO>
Incoherent scattering of light by a Bose--Einstein condensate of


  We demonstrate that incoherent photon scattering by a Bose-Einstein
condensate of non-ideal atomic gas is enhanced due to bosonic stimulation of
spontaneous emission, similarly to coherent scattering in forward direction.
Necessary initial population of non-condensate states is provided by quantum
depletion of a condensate caused by interatomic repulsion.

</DOC>
<DOC>
<DOCNO> 152650 </DOCNO>
Low-energy propagation modes on string network


  We study low-energy propagation modes on string network lattice.
Specifically, we consider an infinite two-dimensional regular hexagonal string
network and analyze the low frequency propagation modes on it. The fluctuation
modes tangent to the two-dimensional plane respect the spatial rotational
symmetry on the plane, and are described by Maxwell theory. The gauge symmetry
comes from the marginal deformation of changing the sizes of the loops of the
lattice. The effective Lorentz symmetry respected at low energy will be
violated at high energy.

</DOC>
<DOC>
<DOCNO> 68855 </DOCNO>
Free Energy of a Hot Quark-Gluon Plasma


  Thermal (Th-)QCD properties appear to disagree with lattice (L-)QCD results,
which suggests that Th-QCD does not have a valid perturbative expansion.
However, we reproduce L-QCD using the first order $\alpha_s$ corrections in
Th-QCD.

</DOC>
<DOC>
<DOCNO> 85470 </DOCNO>
Possible measurement of Quintessence and density parameter using strong


  We propose a possible measurement of the time variability of the vacuum
energy using strong gravitational lensing events. As an example we take an
Einstein cross lens HST 14176+5226 and demonstrate that the measurement of the
velocity dispersion with the accuracy of $\pm$ 5 km/sec will have a chance to
determine the time dependence of the vacuum energy as well as the density
parameter with the accuracy of order 0.1 if one fixes the lens model.

</DOC>
<DOC>
<DOCNO> 121832 </DOCNO>
SuperMassive Black Holes in Bulges


  We present spatially extended gas kinematics at parsec-scale resolution for
the nuclear regions of four nearby disk galaxies, and model them as rotation of
a gas disk in the joint potential of the stellar bulge and a putative central
black hole. The targets were selected from a larger set of long-slit spectra
obtained with the Hubble Space Telescope as part of the Survey of Nearby Nuclei
with STIS (SUNNS). They represents the 4 galaxies (of 24) that display
symmetric gas velocity curves consistent with a rotating disk. We derive the
stellar mass distribution from the STIS acquisition images adopting the stellar
mass-to-light ratio normalized so as to match ground-based velocity dispersion
measurements over a large aperture. Subsequently, we constrain the mass of a
putative black hole by matching the gas rotation curve, following two distinct
approaches. In the most general case we explore all the possible disk
orientations, alternatively we constrain the gas disk orientation from the
dust-lane morphology at similar radii. In the latter case the kinematic data
indicate the presence of a central black hole for three of the four objects,
with masses of 10^7 - 10^8 solar masses, representing up to 0.025 % of the host
bulge mass. For one object (NGC2787) the kinematic data alone provide clear
evidence for the presence of a central black hole even without external
constraints on the disk orientation. These results illustrate directly the need
to determine black-hole masses by differing methods for a large number of
objects, demonstrate that the variance in black hole/bulge mass is much larger
than previously claimed, and reinforce the recent finding that the black-hole
mass is tightly correlated with the bulge stellar velocity dispersion.

</DOC>
<DOC>
<DOCNO> 102700 </DOCNO>
Symmetry Results for Finite-Temperature, Relativistic Thomas-Fermi


  In the semi-classical limit, the quantum mechanics of a stationary beam of
counter-streaming relativistic electrons and ions is described by a nonlinear
system of finite-temperature Thomas-Fermi equations. In the high temperature /
low density limit these Thomas-Fermi equations reduce to the (semi-)conformal
system of Bennett equations discussed earlier by Lebowitz and the author. With
the help of a sharp isoperimetric inequality it is shown that any hypothetical
particle density function which is not radially symmetric about and decreasing
away from the beam's axis would violate the virial theorem. Hence, all beams
have the symmetry of the circular cylinder.

</DOC>
<DOC>
<DOCNO> 40286 </DOCNO>
A Study of One-Prong Tau Decays with a Charged Kaon


  From an analysis of the ionisation energy loss of charged particles selected
from 110326 e+e- -> tau+tau- candidates recorded by the OPAL detector at e+e-
centre-of-mass energies near the Z0 resonance, we determine the one-prong tau
decay branching ratios:
  Br(tau- -> nu_tau K- >=0h0) = 1.528 +- 0.039 +- 0.040 %
  Br(tau- -> nu_tau K-) = 0.658 +- 0.024 +- 0.029 % where the h0 notation
refers to a pi0, an eta, a K^0_S, or a K^0_L, and where the first uncertainty
is statistical and the second is systematic.

</DOC>
<DOC>
<DOCNO> 117368 </DOCNO>
Photometric Properties of 47 Clusters of Galaxies: I. The Butcher-Oemler


  We present gri CCD photometry of 44 Abell clusters and 4 cluster candidates.
Twenty one clusters in our sample have spectroscopic redshifts. Fitting a
relation between mean g, r and i magnitudes, and redshift for this subsample,
we have calculated photometric redshifts for the remainder with an estimated
accuracy of 0.03. The resulting redshift range for the sample is 0.03<z<0.38.
Color-magnitude diagrams are presented for the complete sample and used to
study evolution of the galaxy population in the cluster environment. Our
observations show a strong Butcher-Oemler effect (Butcher & Oemler 1978, 1984),
with an increase in the fraction of blue galaxies (f_B) with redshift that
seems more consistent with the steeper relation estimated by Rakos and
Schombert (1995) than with the original one by Butcher & Oemler (1984).
However, in the redshift range between ~ 0.08 and 0.2, where most of our
clusters lie, there is a wide range of f_B values, consistent with no redshift
evolution of the cluster galaxy population. A large range of f_B values is also
seen between ~ 0.2 and 0.3, when Smail at al. (1998) x-ray clusters are added
to our sample. The discrepancies between samples underscore the need for an
unbiased sample to understand how much of the Butcher-Oemler effect is due to
evolution, and how much to selection effects. We also tested the idea proposed
by Garilli et al. (1996) that there is a population of unusually red galaxies
which could be associated either with the field or clusters, but we find that
these objects are all near the limiting magnitude of the images (20.5<r<22) and
have colors that are consistent with those expected for stars or field galaxies
at z ~ 0.7.

</DOC>
<DOC>
<DOCNO> 150700 </DOCNO>
On the correspondence between gravity fields and CFT operators


  It is shown that a nonlinear derivative-dependent transformation of gravity
fields changes correlation functions in a boundary CFT, and, therefore,
corresponds to a change of a basis of operators in the CFT. It is argued that
only non-renormalized structures in correlation functions can be changed by
such a field transformation, and that the study of the response of correlation
functions to gravity field transformations allows one to find them. In the case
of 4-point functions of CPOs in SYM_4 several non-renormalized structures are
found, including the extremal and subextremal ones. It is also checked that
quartic couplings of scalar fields s^I that are dual to extended chiral primary
operators vanish in the subextremal case, as dictated by the
non-renormalization theorem for the subextremal 4-point functions and the
AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 68446 </DOCNO>
Inflation in Models with Large Extra Dimensions Driven by a Bulk Scalar


  We discuss inflation in models with large extra dimensions, driven by a bulk
scalar field. The brane inflaton is then a single effective field, obtained
from the bulk scalar field by scaling. The self interaction terms of the
effective brane inflaton are then naturally suppressed. The picture is
consistent with a fundamental string scale in the TeV range without the problem
of a superlight inflaton. If hybrid inflation is considered, the right
prediction for the density perturbations as observed by COBE can be obtained
without any fine tunning. The bulk inflaton then decays preferentially into
brane Higgses and reheating follows.

</DOC>
<DOC>
<DOCNO> 117110 </DOCNO>
Spin-axis relaxation in spin-exchange collisions of alkali atoms


  We present calculations of spin-relaxation rates of alkali-metal atoms due to
the spin-axis interaction acting in binary collisions between the atoms. We
show that for the high-temperature conditions of interest here, the spin
relaxation rates calculated with classical-path trajectories are nearly the
same as those calculated with the distorted-wave Born approximation. We compare
these calculations to recent experiments that used magnetic decoupling to
isolate spin relaxation due to binary collisions from that due to the formation
of triplet van-der-Waals molecules. The values of the spin-axis coupling
coefficients deduced from measurements of binary collision rates are consistent
with those deduced from molecular decoupling experiments. All the experimental
data is consistent with a simple and physically plausible scaling law for the
spin-axis coupling coefficients.

</DOC>
<DOC>
<DOCNO> 116990 </DOCNO>
Fabrication and Tolerance Issues and their Influence on Multi-Bunch Bbu


  The main linacs of the Next Linear Collider (NLC) will contain several
thousand X-band RDDS (Rounded Damped Detuned Structures). The transverse
wakefield in the structures is reduced by detuning the modal frequencies such
that they destructively interfere and by four damping manifolds per structure
which provide weak damping. Errors in the fabrication of the individual cells
and in the alignment of the cells will reduce the cancellation of the modes.
Here, we calculate the tolerances on random errors in the synchronous
frequencies of the cells and the cell-to-cell alignment.

</DOC>
<DOC>
<DOCNO> 8914 </DOCNO>
Magnetic Double Structure for S=1, 1/2 Mixed-Spin Systems


  We investigate the zero-temperature and the finite-temperature properties of
the two-dimensional antiferromagnetic quantum spin system composed of the s=1/2
and s=1 spins. The spin excitation spectrum as well as the thermodynamic
quantities are computed by means of the Schwinger-boson mean-field theory. We
discuss how the magnetic double structure with the gapful and the gapless
excitations is generated, and apply the results systematically to the Haldane
gap system in a staggered magnetic field and also to the weakly coupled
ferrimagnetic mixed-spin chains. It is confirmed that the results obtained are
consistent with the experiments for the quasi-one-dimensional Haldane compounds
$R_2 \rm BaNiO_5$.

</DOC>
<DOC>
<DOCNO> 10105 </DOCNO>
Low Temperature Anomaly in Mesoscopic Kondo Wires


  We report the observation of an anomalous magnetoresistance in extremely
dilute quasi-one-dimensional AuFe wires at low temperatures, along with a
hysteretic background at low fields. The Kondo resistivity does not show the
unitarity limit down to the lowest temperature, implying uncompensated spin
states. We suggest that the anomalous magnetoresistance may be understood as
the interference correction from the accumulation of geometric phase in the
conduction electron wave function around the localized impurity spin.

</DOC>
<DOC>
<DOCNO> 122997 </DOCNO>
The microarcsecond quasar J1819+3845


  We present new WSRT observations of the micro-arcsecond quasar J1819+3845.
All short term variations are attributed to interstellar scintillation of a
source which is at most 30 micro-arcseconds in diameter. The timescale of the
modulations changes over the year, which we interpret as due to a peculiar
velocity of the scattering medium. The scintillation behaviour can be used to
determine sub-structure in the source.

</DOC>
<DOC>
<DOCNO> 151014 </DOCNO>
The torus and the Klein Bottle amplitude of permutation orbifolds


  The torus and the Klein bottle amplitude coefficients are computed in
permutation orbifolds of RCFT-s in terms of the same quantities in the original
theory and the twist group. An explicit expression is presented for the number
of self conjugate primaries in the orbifold as a polynomial of the total number
of primaries and the number of self conjugate ones in the parent theory. The
formulae in the $Z_2$ orbifold illustrate the general results.

</DOC>
<DOC>
<DOCNO> 68525 </DOCNO>
Large N_c, Constituent Quarks, and N, Delta Charge Radii


  We show how one may define baryon constituent quarks in a rigorous manner,
given physical assumptions that hold in the large-N_c limit of QCD. This
constituent picture gives rise to an operator expansion that has been used to
study large-N_c baryon observables; here we apply it to the case of charge
radii of the N and Delta states, using minimal dynamical assumptions. For
example, one finds the relation r_p^2 - r_{Delta^+}^2 = r_n^2 - r_{Delta^0}^2
to be broken only by three-body, O(1/N_c^2) effects for any N_c.

</DOC>
<DOC>
<DOCNO> 170642 </DOCNO>
On the units of bipartite entanglement: Is sixteen ounces of


  In a good physical theory dimensionless quantities such as the ratio m_p /
m_e of the mass of the proton to the mass of the electron do not depend on the
system of units being used. This paper demonstrates that one widely used method
for defining measures of entanglement violates this principle. Specifically, in
this approach dimensionless ratios E(rho) / E(sigma) of entanglement measures
may depend on what state is chosen as the basic unit of entanglement. This
observation leads us to suggest three novel approaches to the quantification of
entanglement. These approaches lead to unit-free definitions for the
entanglement of formation and the distillable entanglement, and suggest natural
measures of entanglement for multipartite systems. We also show that the
behaviour of one of these novel measures, the entanglement of computation, is
related to some open problems in computational complexity.

</DOC>
<DOC>
<DOCNO> 121826 </DOCNO>
Pulsar spectra of radio emission


  We have collected pulsar flux density observations and compiled spectra of
281 objects. The database of Lorimer et al. (\cite{lorimer}) has been extended
to frequencies higher than 1.4 GHz and lower than 300 MHz. Our results show
that above 100 MHz the spectra of the majority of pulsars can be described by a
simple power law with average value of spectral index $<\alpha> = -1.8\pm0.2$.
A rigorous analysis of spectral fitting revealed only about 5% of spectra which
can be modelled by the two power law. Thus, it seems that single power law is a
rule and the two power law spectrum is a rather rare exception, of an unknown
origin, to this rule. We have recognized a small number of pulsars with almost
flat spectrum ($\alpha \geq -1.0$) in the wide frequency range (from 300 MHz to
20 GHz) as well as few pulsars with a turn-over at unusually high frequency
($\sim$~1 GHz).

</DOC>
<DOC>
<DOCNO> 10804 </DOCNO>
Landscape statistics of the low autocorrelated binary string problem


  The statistical properties of the energy landscape of the low autocorrelated
binary string problem (LABSP) are studied numerically and compared with those
of several classic disordered models. Using two global measures of landscape
structure which have been introduced in the Simulated Annealing literature,
namely, depth and difficulty, we find that the landscape of LABSP, except
perhaps for a very large degeneracy of the local minima energies, is
qualitatively similar to some well-known landscapes such as that of the
mean-field 2-spin glass model. Furthermore, we consider a mean-field
approximation to the pure model proposed by Bouchaud and Mezard (1994, J.
Physique I France 4 1109) and show both analytically and numerically that it
describes extremely well the statistical properties of LABSP.

</DOC>
<DOC>
<DOCNO> 119319 </DOCNO>
On the Optical Light Curves of Afterglows from Jetted Gamma-ray Burst


  Due to some refinements in the dynamics, we can follow the overall evolution
of a realistic jet numerically till its bulk velocity being as small as $\beta
c \sim 10^{-3} c$. We find no obvious break in the optical light curve during
the relativistic phase itself. However, an obvious break does exist at
the transition from the relativistic phase to the non-relativistic phase, which
typically occurs at time $t \sim 10^6$ --- $10^{6.5}$ s (i.e., 10 --- 30 d).
The break is affected by many parameters, such as the electron energy fraction
$\xi_{\rm e}$, the magnetic energy fraction $\xi_{\rm B}^2$, the initial half
opening angle $\theta_0$, and the medium number density $n$. Increase of any of
them to a large enough value will make the break disappear. Although the break
itself is parameter-dependent, afterglows from jetted GRB remnants are
uniformly characterized by a quick decay during the non-relativistic phase,
with power law timing index $\alpha \geq 2.1$. This is quite different from
that of isotropic fireballs, and may be of fundamental importance for
determining the degree of beaming in $\gamma$-ray bursts observationally.

</DOC>
<DOC>
<DOCNO> 119392 </DOCNO>
The characteristics of high velocity O and B stars which are ejected


  We perform binary population synthesis calculations to study the origin and
the characteristics of runaway O and B stars which are ejected by the supernova
explosion of the companion star in a binary system. The number of OB runaways
can be explained from supernova ejections only if: high mass stars are
preferentially formed in binaries, the initial mass ratio distribution is
strongly peaked to unity and stars are rejuvenated to zero age upon accretion
of mass from a companion star. Taking these requirements into consideration we
conclude that at most 30% of the runaway O stars but possibly all runaway B
stars obtain high velocities due to supernovae in evolving binaries. Stars
which obtain high velocities via supernova ejections have the following
characteristics: 1) at least 10% of the high velocity B stars and half the O
stars have a mass greater than the turn off mass of the cluster in which they
are born and would be observed as blue stragglers in the parent cluster, 2)
their equatorial rotational velocities are proportional to their space velocity
and 3) between 20% and 40% of the runaways have neutron star companions but
less than 1% are visible as radio pulsars in part of the orbit.

</DOC>
<DOC>
<DOCNO> 70910 </DOCNO>
Scenario for Ultrarelativistic Nuclear Collisions: V. Onset of


  We consider a Euclidean extension of the wedge form of Hamiltonian dynamics,
which explicitly accounts for the strong localization of the first interaction
in nuclear collisions. A new principle of the analytic continuation via the
tetrad vector is introduced. We discover the existence of self-dual solutions
with short life-times (ephemerons) and conjecture that these vacuum
fluctuations can lower the Euclidean action of the system of the colliding
nuclei, thus enforcing a breakdown of the nuclei coherence. We suggest that the
ephemerons can be identified with the gluons-partons, which are resolved in
high-energy nuclear collisions.

</DOC>
<DOC>
<DOCNO> 68165 </DOCNO>
Non-Baryonic Dark Matter - Observational Evidence and Detection Methods


  The evidence for the existence of dark matter in the universe is reviewed. A
general picture emerges, where both baryonic and non-baryonic dark matter is
needed to explain current observations. In particular, a wealth of
observational information points to the existence of a non-baryonic component,
contributing between around 20 and 40 percent of the critical mass density
needed to make the universe geometrically flat on large scales. In addition, an
even larger contribution from vacuum energy (or cosmological constant) is
indicated by recent observations. To the theoretically favoured particle
candidates for non-baryonic dark matter belong axions, supersymmetric
particles, and of less importance, massive neutrinos. The theoretical
foundation and experimental situation for each of these is reviewed. Direct and
indirect methods for detection of supersymmetric dark matter are described in
some detail. Present experiments are just reaching the required sensitivity to
discover or rule out some of these candidates, and major improvements are
planned over the coming years.

</DOC>
<DOC>
<DOCNO> 150871 </DOCNO>
Some Problems in Defining Functional Integration over the Gauge Group


  We find that sometimes the usual definition of functional integration over
the gauge group through limiting process may have internal difficulties.

</DOC>
<DOC>
<DOCNO> 151594 </DOCNO>
Supergravity and Light-Like Non-commutativity


  We construct dual supergravity descriptions of field theories and little
string theories with light-like non-commutativity. The field theories are
realized on the world-volume of Dp branes with light-like NS $B$ field and M5
branes with light-like $C$ field. The little string theories are realized on
the world-volume of NS5 branes with light-like RR $A$ fields. The supergravity
backgrounds are closely related to the $A=0,B=0,C=0$ backgrounds. We discuss
the implications of these results. We also construct dual supergravity
descriptions of ODp theories realized on the worldvolume of NS5 branes with RR
backgrounds.

</DOC>
<DOC>
<DOCNO> 70093 </DOCNO>
Dynamical Instability of Brane Solutions with a Self-Tuning Cosmological


  A five-dimensional solution to Einstein's equations coupled to a scalar field
has been proposed as a partial solution to the cosmological constant problem:
the effect of arbitrary vacuum energy (tension) of a 3-brane is cancelled;
however, the scalar field becomes singular at some finite proper distance in
the extra dimension. We show that in the original model with a vanishing bulk
potential for the scalar, the solution is a saddle point which is unstable to
expansion or contraction of the brane world. We construct exact time-dependent
solutions which generalize the static solution, and demonstrate that they do
not conserve energy on the brane; thus they do not have an effective 4-D field
theoretic description. When a bulk scalar field potential is added, the
boundary conditions on the brane cannot be trivially satisfied, raising hope
that the self-tuning mechanism may still give some insight into the
cosmological constant problem in this case.

</DOC>
<DOC>
<DOCNO> 8055 </DOCNO>
Bose-Einstein Condensation in Dissipative Systems far from Thermal


  It is shown, that Bose-Einstein condensation can occur not only in spatially
extended equilibrium systems, but also in the systems far from thermal
equilibrium, which show order-disorder phase transition. The investigation is
performed by solving the Complex Ginzburg-Landau equation, a universal model
for nonequilibrium order-disorder phase transitions.

</DOC>
<DOC>
<DOCNO> 40102 </DOCNO>
Precision Measurements of the W-Boson Mass


  The Standard Model of electroweak interactions has had great success in
describing the observed data over the last three decades. The precision of
experimental measurements affords tests of the Standard Model at the quantum
loop level beyond leading order. Despite this great success it is important to
continue confronting experimental measurements with the Standard Model
predictions as any deviation would signal new physics. As a fundamental
parameter of the Standard Model, the mass of the W-boson, M_W, is of particular
importance. Aside from being an important test of the SM itself, a precision
measurement of M_W can be used to constrain the mass of the Higgs boson, M_H.
In this article we review the principal experimental techniques for determining
M_W and discuss their combination into a single precision M_W measurement,
which is then used to yield constraints on M_H. We conclude by briefly
discussing future prospects for precision measurements of the W-boson mass.

</DOC>
<DOC>
<DOCNO> 102551 </DOCNO>
Conformal field theory, boundary conditions and applications to string


  This is an introduction to two-dimensional conformal field theory and its
applications in string theory. Modern concepts of conformal field theory are
explained, and it is outlined how they are used in recent studies of D-branes
in the strong curvature regime by means of CFT on surfaces with boundary.

</DOC>
<DOC>
<DOCNO> 9896 </DOCNO>
Force distributions near the jamming and glass transitions


  We calculate the distribution of interparticle normal forces $P(F)$ near the
glass and jamming transitions in model supercooled liquids and foams,
respectively. $P(F)$ develops a peak that appears near the glass or jamming
transitions, whose height increases with decreasing temperature, decreasing
shear stress and increasing packing density. A similar shape of $P(F)$ was
observed in experiments on static granular packings. We propose that the
appearance of this peak signals the development of a yield stress. The
sensitivity of the peak to temperature, shear stress and density lends credence
to the recently proposed generalized jamming phase diagram.

</DOC>
<DOC>
<DOCNO> 80759 </DOCNO>
Perturbative renormalization factors of $\Delta S = 1$ four-quark


  Renormalization factors for $\Delta S =1$ four-quark operators in the
effective weak Hamiltonian are perturbatively evaluated in domain-wall QCD. The
one-loop corrections of $\Delta S=1$ four-quark operators consist of two types
of diagrams: one is gluon exchange between quark lines and the other is penguin
diagrams containing quark loops. Combining both contributions, our results
allow a lattice calculation of the amplitude for $K\to \pi\pi$ decays with
$O(g^2)$ corrections included.

</DOC>
<DOC>
<DOCNO> 170166 </DOCNO>
Kolmogorov and von Mises viewpoints to the Greenburger-Horne-Zeilinger


  We present comparative probabilistic analysis of the
Greenburger-Horne-Zeilinger paradox in the frameworks of Kolmogorov's
(measure-theoretical) and von Mises' (frequency) models of the probability
theory. This analysis demonstrated that the GHZ paradox is merely a consequence
of the use of Kolmogorov's probabilistic model. By using von Mises' frequency
approach we escape the contradiction between the local realism and quantum
formalism. The frequency approach implies automatically contextual
interpretation of quantum formalism: different collectives induce different
probability distributions. On the other hand, the formal use of Kolmogorov's
model implies the identification of such distributions with one abstract
Kolmogorov measure. In the measure-theoretical approach we can escape the
paradox, if we do not suppose that probability distributions corresponding to
different settings of measurement devices are equivalent. We discuss the
connection between equivalence/singularity dichotomy in measure theory and the
existence of compatible and noncompatible observables.

</DOC>
<DOC>
<DOCNO> 174574 </DOCNO>
Measurement of the F2n/F2p and d/u Ratios in Deep Inelastic Electron


  We discuss a possible measurement of the ratio of the nucleon structure
functions, F2n/F2p, and the ratio of the up to down quark distributions, u/d,
at large x, by performing deep inelastic electron scattering from the 3H and
3He mirror nuclei with the 11 GeV upgraded beam of Jefferson Lab. The
measurement is expected to be almost free of nuclear effects, which introduce a
significant uncertainty in the extraction of these two ratios from deep
inelastic scattering off the proton and deuteron. The results are expected to
test perturbative and non-perturbative mechanisms of spin-flavor symmetry
breaking in the nucleon, and constrain the structure function parameterizations
needed for the interpretation of high energy e-p, p-p and p-pbar collider data.
The precision of the expected data can also allow for testing competing
parameterizations of the nuclear EMC effect and provide valuable constraints on
models of its dynamical origin.

</DOC>
<DOC>
<DOCNO> 118543 </DOCNO>
Pressure-driven outflow from a dynamo active disc


  We present a numerical model of an accretion disc with mean-field dynamo
action that develops a fast pressure-driven outflow within a cone near the
rotation axis and a slower centrifugally driven outflow in the outer parts of
the disc. The fast outflow in the cone is confined by the azimuthal field which
is produced by the dynamo in the disc and advected to the disc corona. The fast
outflow has low angular momentum and, in the presence of magnetic fields, is
hotter and denser than its surroundings. The cone's half-opening angle is about
30 degrees near the disc and decreases slightly with height. The slow outflow
transports significant amounts of magnetic energy into the surrounding medium.
The general structure of the outflow is similar to that inferred for the BN/KL
region in the Orion Nebula.

</DOC>
<DOC>
<DOCNO> 178630 </DOCNO>
Semiempirical Shell Model Masses with Magic Number Z = 126 for


  A semiempirical shell model mass equation applicable to superheavy elements
up to Z = 126 is presented and shown to have a high predictive power. The
equation is applied to the recently discovered superheavy nuclei Z = 118, A =
293 and Z = 114, A = 289 and their decay products.

</DOC>
<DOC>
<DOCNO> 121762 </DOCNO>
The Friedmann-Lemaitre models in perspective


  I show that all FRW models (four dimensional pseudo-Riemannian manifolds with
maximally symmetric space) can be embedded in a flat Minkowski manifold with 5
dimensions. The pseudo Riemannian metric of space-time is induced by the flat
metric. This generalizes the usual embedding widely used for the \dS ~models. I
give the coordinate transformations for the embedding. Taking into account the
spatial isotropy, one can reduce space-time to a two-dimensional surface,
embedded in a three-dimensional Minkowski space. This allows to give exact
graphic representations of the FRW models, and in particular of their
curvature.

</DOC>
<DOC>
<DOCNO> 100557 </DOCNO>
0^# and elementary end extensions of V_k


  In this paper we prove that if k is a cardinal in L[0^#], then there is an
inner model M such that M |= (V_k,E) has no elementary end extension. In
particular if 0^# exists then weak compactness is never downwards absolute. We
complement the result with a lemma stating that any cardinal greater than
aleph_1 of uncountable cofinality in L[0^#] is Mahlo in every strict inner
model of L[0^#].

</DOC>
<DOC>
<DOCNO> 170085 </DOCNO>
On the Observables Describing a Quantum Reference Frame


  A reference frame F is described by the element g of the Poincare' group P
which connects F with a given fixed frame F_0. If F is a quantum frame, defined
by a physical object following the laws of quantum physics, the parameters of g
have to be considered as quantum observables. However, these observables are
not compatible and some of them, namely the coordinates of the origin of F,
cannot be represented by self-adjoint operators. Both these difficulties can be
overcome by considering a positive-operator-valued measure (POVM) on P,
covariant with respect to the left translations of the group, namely a
covariance system. We develop a construction procedure for this kind of
mathematical structure. The formalism is also used to discuss the quantum
observables measured with respect to a quantum reference frame.

</DOC>
<DOC>
<DOCNO> 117076 </DOCNO>
Numerical Studies on Locally Damped Structures


  In the JLC/NLC X-band linear collider, it is essential to reduce the
long-range dipole wakefields in the accelerator structure to prevent beam break
up (BBU) and emittance degradation. The two methods of reducing the long-range
wakefields are detuning and damping. Detuning reduces the wakefields rapidly as
the dipole modes de-cohere but, with a finite number of modes, the wakefield
will grow again as the modes re-cohere. In contrast, damping suppresses the
wakefields at a longer distance. There are two principal damping schemes:
synchronous damping using HOM manifolds such as that used in the RDDS1
structure and local damping similar to that used in the CLIC structure. In a
locally damped scheme, one can obtain almost any Q value, however, the damping
can have significant effects on the accelerating mode. In this paper, we
present a medium local-damping scheme where the wakefields are controlled to
meet the BBU requirement while minimizing the degradations of the fundamental
rf parameters. We will address the load design and pulse heating issues
associated with the medium damping scheme.

</DOC>
<DOC>
<DOCNO> 119166 </DOCNO>
Circumnuclear regions in barred spiral galaxies. I. Near-infrared


  We present sub-arcsecond resolution ground-based near-infrared images of the
central regions of a sample of twelve barred galaxies with circumnuclear star
formation activity, which is organized in ring-like regions typically one
kiloparsec in diameter. We also present Hubble Space Telescope near-infrared
images of ten of our sample galaxies, and compare them with our ground-based
data. Although our sample galaxies were selected for the presence of
circumnuclear star formation activity, our broad-band near-infrared images are
heterogeneous, showing a substantial amount of small-scale structure in some
galaxies, and practically none in others. We argue that, where it exists, this
structure is caused by young stars, which also cause the characteristic bumps
or changes in slope in the radial profiles of ellipticity, major axis position
angle, surface brightness and colour at the radius of the circumnuclear ring in
most of our sample galaxies. In 7 out of 10 HST images, star formation in the
nuclear ring is clearly visible as a large number of small emitting regions,
organised into spiral arm fragments, which are accompanied by dust lanes. NIR
colour index maps show much more clearly the location of dust lanes and, in
certain cases, regions of star formation than single broad-band images.
Circumnuclear spiral structure thus outlined appears to be common in barred
spiral galaxies with circumnuclear star formation.

</DOC>
<DOC>
<DOCNO> 13840 </DOCNO>
Role of dynamic Jahn-Teller distortions in Na2C60 and Na2CsC60 studied


  Through 13C NMR spin lattice relaxation (T1) measurements in cubic Na2C60, we
detect a gap in its electronic excitations, similar to that observed in
tetragonal A4C60. This establishes that Jahn-Teller distortions (JTD) and
strong electronic correlations must be considered to understand the behaviour
of even electron systems, regardless of the structure. Furthermore, in metallic
Na2CsC60, a similar contribution to T1 is also detected for 13C and 133Cs NMR,
implying the occurence of excitations typical of JT distorted C60^{2-} (or
equivalently C60^{4-}). This supports the idea that dynamic JTD can induce
attractive electronic interactions in odd electron systems.

</DOC>
<DOC>
<DOCNO> 85656 </DOCNO>
The Quantum Vacuum and the Cosmological Constant Problem


  The cosmological constant problem arises at the intersection between general
relativity and quantum field theory, and is regarded as a fundamental problem
in modern physics. In this paper we describe the historical and conceptual
origin of the cosmological constant problem which is intimately connected to
the vacuum concept in quantum field theory. We critically discuss how the
problem rests on the notion of physical real vacuum energy, and which relations
between general relativity and quantum field theory are assumed in order to
make the problem well-defined.

</DOC>
<DOC>
<DOCNO> 68350 </DOCNO>
Cosmological Strucure Formation with Topological Defects


  Structure formation with topological defects is described. The main
differences from inflationary models are highlighted. The results are compared
with recent observations. It is concluded that all the defect models studied so
far are in disagreement with recent observations of CMB anisotropies.
Furthermore, present observations do not support 'decoherence', a generic
feature of structure formation from topological defects.

</DOC>
<DOC>
<DOCNO> 12414 </DOCNO>
From the zero-field metal-insulator transition in two dimensions to the


  Effective-medium theory is applied to the percolation description of the
metal-insulator transition in two dimensions with emphasis on the continuous
connection between the zero-magnetic-field transition and the quantum Hall
transition. In this model the system consists of puddles connected via saddle
points, and there is loss of quantum coherence inside the puddles. The
effective conductance of the network is calculated using appropriate
integration over the distribution of conductances, leading to a determination
of the magnetic field dependence of the critical density. Excellent
quantitative agreement is obtained with the experimental data, which allows an
estimate of the puddle physical parameters.

</DOC>
<DOC>
<DOCNO> 169809 </DOCNO>
Line narrowing via cavity-induced quantum interference in a $\Xi $-type


  We show that cavity-induced interference may result in spectral line
narrowing in the absorption spectrum of a $\Xi$-type atom coupled to a
single-mode, frequency-tunable cavity field with a pre-selected polarization at
finite temperature.

</DOC>
<DOC>
<DOCNO> 121399 </DOCNO>
A Fitting Formula for the Non-Linear Evolution of the Bispectrum


  We present a fitting formula for the non-linear evolution of the bispectrum
in CDM models, obtained from measurements in high resolution numerical
simulations. The formula interpolates between the perturbative and highly
non-linear regimes, and generalizes previous results obtained for scale-free
initial conditions.

</DOC>
<DOC>
<DOCNO> 118298 </DOCNO>
A Near Infrared Polarized Bipolar Cone in the CIRCINUS Galaxy


  We present near-infrared broad-band polarization images of the nuclear
regions of the Circinus galaxy in the J, H and K bands. For the first time the
south-eastern reflection cone is detected in polarized light, which is obscured
at optical wavelengths behind the galactic disk. This biconical structure is
clearly observed in J and H band polarized flux whilst in the K band a more
compact structure is detected. Total flux J-K and H-K colour maps reveal a
complex colour gradient toward the south-east direction (where the Circinus
galactic disk is nearer to us). We find enhanced extinction in an arc shaped
structure, at about 200pc from the nucleus, probably part of the star-formation
ring.
  We model the polarized flux images with the scattering and torus model of
Young etal, with the same basic input parameters as used by Alexander etal in
the spectropolarimetry modelling of Circinus. The best fit to the polarized
flux is achieved with a torus radius of ~16pc, and a visual extinction Av,
through the torus, to the near-infrared emission regions of >66 mags.

</DOC>
<DOC>
<DOCNO> 39724 </DOCNO>
A Measurement of the Mass and Full-Width of the $\eta_c$ Meson


  In a sample of 7.8 million $J/\psi$ decays collected in the Beijing
Spectrometer, the process J/$\psi\to\gamma\eta_c$ is observed for five
different $\eta_c$ decay channels: $K^+K^-\pi^+\pi^-$, $\pi^+\pi^-\pi^+\pi^-$,
$K^\pm K^0_S \pi^\mp$ (with $K^0_S\to\pi^+\pi^-$), $\phi\phi$ (with $\phi\to
K^+K^-$) and $K^+K^-\pi^0$. From these signals, we determine the mass of
$\eta_c$ to be $2976.6\pm2.9\pm1.3$ MeV. Combining this result with a
previously reported result from a similar study using $\psi(2S)\to\gamma\eta_c$
detected in the same spectrometer gives $m_{\eta_c} = 2976.3\pm2.3\pm1.2$ MeV.
For the combined samples, we obtain $\Gamma_{\eta_c} = 11.0\pm 8.1\pm 4.1$ MeV.

</DOC>
<DOC>
<DOCNO> 84815 </DOCNO>
Birth of timelike naked singularity


  We investigate the causal structure of the Harada-Iguchi-Nakao (HIN)'s exact
solution in detail, which describes the dynamical formation of naked
singularity in the collapse of a regular spherical cluster of counterrotating
particles. There are three kinds of radial null geodesics in the HIN spacetime.
One is the regular null geodesics and the other two are the null geodesics
which terminate at the singularity. The central massless singularity is
timelike naked singularity and satisfies the strong curvature condition along
the null geodesics except for the instant of singularity formation. The cluster
dynamically asymptotes to the singular static Einstein cluster in which
centrifugal force is balanced with gravity. The HIN solution provides an
interesting example which demonstrates that collisionless particles invoke
timelike naked singularity.

</DOC>
<DOC>
<DOCNO> 69121 </DOCNO>
The double parton distributions in the hard pomeron model


  We study the double parton interaction process in collisions between highly
virtual $q{\bar q}$ pairs in the BFKL regime. Explicit expressions for the
double parton distributions are obtained both in the case of direct coupling of
the BFKL pomerons to the $q{\bar q}$ pair and in the case of triple pomeron
interaction.

</DOC>
<DOC>
<DOCNO> 71260 </DOCNO>
Borel Resummation of the Perturbative Free Energy of Hot Yang-Mills


  The divergent perturbative expansion of the free-energy density of thermal
SU(3) gauge theory is resummed into a rapidly convergent series using a novel,
variational, implementation of the method of conformal mapping of the
corresponding Borel series. The resummed result differs significantly from
non-perturbative lattice simulations and the discrepancy is attributed to the
presence of a pole on the positive axis of the Borel plane. The position of
that pole is determined numerically and the difference between the lattice data
and the resummed series is related to a phenomenological bag `constant'.

</DOC>
<DOC>
<DOCNO> 121250 </DOCNO>
Emission Beam Geometry of Selected Pulsars Derived from Average Pulse


  By fitting the classical Rotating Vector Model (RVM) to high quality
polarization data for selected radio pulsars, we find the inclination of the
magnetic axis to the spin axis, alpha, as well as the minimum angle between the
line of sight and the magnetic axis, beta, for ten objects. We give a full
treatment of statistical errors in the fitting process. We also present a
dictionary and conversion table of various investigators' geometric definitions
to facilitate future comparisons. We compare our results with other RVM fits
and with empirical/geometrical (E/G) approaches, and we examine the strengths
and weaknesses of RVM fits and E/G investigations for the determination of
pulsar emission beam geometry. Our fits to B0950+08 show that it is an
orthogonal rotator, contrary to previous findings. Finally, we find that RVM
fits are easily perturbed by systematic effects in polarized position angles,
and that the formal uncertainties significantly underestimate the actual
errors.

</DOC>
<DOC>
<DOCNO> 170610 </DOCNO>
The Wigner Kernel of a Particle obtained from the Wigner Kernel of a


  The Moyal formalism for a particle can be derived from the Moyal formalism
for a spin. This is done by contracting the group of rotations to the
oscillator group. A new derivation is given for the contraction of the spin
Wigner-kernel to the Wigner kernel of a particle.

</DOC>
<DOC>
<DOCNO> 12727 </DOCNO>
The Range of Validity for the Kelvin Force


  In a recent Letter, Luo, Du and Huang reported a novel convective instability
driven by a force rarely studied before -- that exerted by an external magnetic
field on a strongly magnetizable liquid. The associated physics is surprisingly
rich and promises many more interesting results for the future. Unfortunately,
the analysis starts from a misconception and employs the Kelvin force outside
its range of validity. Since few would recognize this as a mistake, and since
its consequence in the given experiment is particularly direct and critical,
this is a point well worth being clarified, and clearly understood.

</DOC>
<DOC>
<DOCNO> 116991 </DOCNO>
Pulsed SC Proton Linac


  The superconducting (SC) proton linac is proposed in the JAERI/KEK Joint
Project for a high-intensity proton accelerator in the energy region from 400
to 600 MeV. Highly stable fields in the SC cavities are required under the
dynamic Lorentz force detuning. A new model describing the dynamic Lorentz
detuning has been developed and the validity has been confirmed experimentally.
The model has been applied successfully to the rf control simulation of the SC
proton linac.

</DOC>
<DOC>
<DOCNO> 11373 </DOCNO>
Cascade process of vortex tangle dynamics in superfluid $^4$He without


  Recently the Kelvin wave cascade process in superfluid $^4$He at very low
temperatures was discussed. In this mechanism, the dynamics of the waves on the
vortex lines plays an important role. In order to investigate this mechanism,
we study numerically the dynamics of the waves on the reconnected vortex lines
using the full Biot-Savart law. This work shows the reconnection of two
vortices leads to the waves on the reconnected vortex lines. To discuss the
energy of the waves on the vortex lines, the energy spectrum of the superflow
before and after the reconnection is calculated.

</DOC>
<DOC>
<DOCNO> 122486 </DOCNO>
Conservation of Magnetic Helicity and Its Constraint on $\alpha$-Effect


  Dynamical studies of MHD turbulence on the one hand, and arguments based upon
magnetic helicity on the other, have yielded seemingly contradictory estimates
for the $\alpha$ parameter in turbulent dynamo theory. Here we show, with
direct numerical simulation of three-dimensional magnetohydrodynamic turbulence
with a mean magnetic field, $\OB$, that the constraint on the dynamo
$\alpha$-effect set by the magnetic helicity is time-dependent. A time-scale
$t_c$ is introduced such that for $t<t_c$, the $\alpha$-coefficient calculated
from the simulation is close to the result of Pouquet et al and Field et al,
$-\frac{\tau_{cor}}{3}(< \v \cdot \nabla \times \v > - < \b \cdot \nabla \times
\b >)$; for $t>t_c$, the classical result of the $\alpha$-coefficient given by
the Mean-Field Electrodynamics is reduced by a factor of $1/({R_m
|\OB|^2/v_{rms}^2})$, as argued by Gruzinov & Diamond, Seehafer and Cattaneo &
Hughes. Here, $R_m$ is the magnetic Reynolds number, $v_{rms}$ the rms velocity
of the turbulence, $\tau_{cor}$ the correlation time of the turbulence, and
$\overline B$ is in velocity unit. The applicability of and connection between
different models of dynamo theory are also discussed.

</DOC>
<DOC>
<DOCNO> 7960 </DOCNO>
Structure of Electrorheological Fluids


  Specially synthesized silica colloidal spheres with fluorescent cores were
used as model electrorheological fluids to experimentally explore structure
formation and evolution under conditions of no shear. Using Confocal Scanning
Laser Microscopy we measured the location of each colloid in three dimensions.
We observed an equilibrium body-centered tetragonal phase and several
non-equilibrium structures such as sheet-like labyrinths and isolated chains of
colloids. The formation of non-equilibrium structures was studied as a function
of the volume fraction, electric field strength and starting configuration of
the colloid. We compare our observations to previous experiments, simulations
and calculations.

</DOC>
<DOC>
<DOCNO> 71227 </DOCNO>
One-loop leading logarithms in electroweak radiative corrections, I.


  We present results for the complete one-loop electroweak logarithmic
corrections for general processes at high energies and fixed angles. Our
results are applicable to arbitrary matrix elements that are not
mass-suppressed. We give explicit results for 4-fermion processes and
gauge-boson-pair production in electron-positron annihilation.

</DOC>
<DOC>
<DOCNO> 119548 </DOCNO>
HST revisits the proper motion of PSR B0656+14


  We report the first successful measurement (with HST/WFPC2) of a significant
proper motion for a V~ 25 object which we had proposed as the optical
counterpart of the radio pulsar PSR B0656+14. The yearly displacement of 43+/-
2 mas is highly significant and, while in agreement with early, rougher, radio
measurements, stands out for its vastly improved accuracy. Together with the
report of a possible optical pulsation (Shearer et al. 1998), we regard this
result as the final proof of the optical identification of PSR B0656+14.

</DOC>
<DOC>
<DOCNO> 71550 </DOCNO>
Ultrahigh energy cosmic rays and new particle physics


  The current status of the ultrahigh energy cosmic ray (UHE CR) enigma and
several proposed solutions involving particle physics beyond the standard model
are discussed. Emphasis is given to top--down models, and as a main example,
supermassive dark matter as galactic source for UHE CR and the status of its
experimental signatures (galactic anisotropy, chemical composition and
clustering) is reviewed. Then different approaches to calculate fragmentation
spectra of supermassive particles are discussed. Finally, it is argued that UHE
neutrinos cannot be - neither directly or indirectly - responsible for the
observed vertical air showers.

</DOC>
<DOC>
<DOCNO> 12721 </DOCNO>
Spin effects in ferromagnetic single-electron transistors


  Electron tunneling in ferromagnetic single-electron transistors is considered
theoretically in the sequential tunneling regime. A new formalism is developed,
which operates in a two-dimensional space of states, instead of one-dimensiona
space used in the spinless case. It is shown that spin fluctuations can be
significantly larger than the charge fluctuations. The influence of discrete
energy spectrum of a small central electrode on tunneling current, charge and
spin accumulation, charge and spin fluctuations, and on tunnel
magnetoresistance is analyzed in details. Two different scales are found in the
bias dependence of the basic transport characteristics; the shorter one
originates from the discrete energy spectrum and the longer one from discrete
charging of the central electrode. The features due to discrete spectrum and
discrete charging disappear at high temperatures.

</DOC>
<DOC>
<DOCNO> 12603 </DOCNO>
Ginsburg-Landau Expansion in a non-Fermi Superconductor


  We study the Ginsburg-Landau expansion for the non-Fermi model proposed by
Anderson. We analyze the deviations of the main properties of a non-Fermi
superconductor from the isotropic s-wave bidimensiona superconductor.

</DOC>
<DOC>
<DOCNO> 84899 </DOCNO>
Solitons and black holes in Einstein-Born-Infeld-dilaton theory


  Static spherically symmetric asymptotically flat solutions to the U(1)
Born-Infeld theory coupled to gravity and to a dilaton are investigated. The
dilaton enters in such a way that the theory is $SL(2,R)$- symmetric for a unit
value of the dilaton coupling constant. We find globally regular solutions for
any value of the effective coupling which is the ratio of the gravitational and
dilaton couplings; they form a continuous sequence labeled by the sole free
parameter of the local solution near the origin. The allowed values of this
parameter are bounded from below, and, as the limiting value is approached, the
mass and the dilaton charge rise indefinitely and tend to a strict equality (in
suitable units). Together with the electric charge they saturate the BPS bound
of the corresponding linear U(1) theory. Beyond this boundary the solutions
become compact (singular), while the limiting solution at the exact boundary
value is non-compact and non-asymptotically flat. The black holes in this
theory exist for any value of the event horizon radius and also form a sequence
labelled by a continuously varying parameter restricted to a finite interval.
The singularity inside the black hole exhibits a power-law mass inflation.

</DOC>
<DOC>
<DOCNO> 9194 </DOCNO>
Test of molecular mode coupling theory: A first resume


  We report recent progress on the test of mode coupling theory for molecular
liquids (MMCT) for molecules of arbitrary shape. The MMCT equations in the long
time limit are solved for supercooled water including all molecular degrees of
freedom. In contrast to our earlier treatment of water as a linear molecule, we
find that the glass transition temperature $T_c$ is overestimated by the theory
as was found in the case of simple liquids. The nonergodicity parameters are
calculated from the "full" set of MMCT-equations truncated at $l_{co}=2$. These
results are compared $(i)$ with the nonergodicity parameters from MMCT with
$l_{co}=2$ in the "dipole" approximation $n=n'=0$ and the diagonalization
approximation $n=n'=0$,$l=l'$ and $(ii)$ with the corresponding results from a
MD-simulation. This work supports the possibility that a reduction to the most
prominent correlators may constitute a valid approximation for solving the MMCT
equations for rigid molecules.

</DOC>
<DOC>
<DOCNO> 99301 </DOCNO>
Random Walks and Electric Networks


  A popular account of the connection between random walks and electric
networks.

</DOC>
<DOC>
<DOCNO> 70758 </DOCNO>
Fractional Fokker-Planck Equation and Oscillatory Behavior of Cumulant


  The Fokker-Planck equation is considered, which is connected to the birth and
death process with immigration by the Poisson transform. The fractional
derivative in time variable is introduced into the Fokker-Planck equation. From
its solution (the probability density function), the generating function (GF)
for the corresponding probability distribution is derived. We consider the case
when the GF reduces to that of the negative binomial distribution (NBD), if the
fractional derivative is replaced to the ordinary one. Formulas of the
factorial moment and the $H_j$ moment are derived from the GF. The $H_j$ moment
derived from the GF of the NBD decreases monotonously as the rank j increases.
However, the $H_j$ moment derived in our approach oscillates, which is
contrasted with the case of the NBD. Calculated $H_j$ moments are compared with
those given from the data in $p\bar{p}$ collisions and in $e^+e^-$ collisions.

</DOC>
<DOC>
<DOCNO> 9540 </DOCNO>
Effect of Thermal Undulations on the Bending Elasticity and Spontaneous


  We amplify previous arguments why mean curvature should be used as measure of
integration in calculating the effective bending rigidity of fluid membranes
subjected to a weak background curvature. The stiffening of the membrane by its
fluctuations, recently derived for spherical shapes, is recovered for
cylindrical curvature. Employing curvilinear coordinates, we then discuss
stiffening for arbitrary shapes, confirm that the elastic modulus of Gaussian
curvature is not renormalized in the presence of fluctuations, and show for the
first time that any spontaneous curvature also remains unchanged.

</DOC>
<DOC>
<DOCNO> 101137 </DOCNO>
Host Algebras


  A host algebra generalises the concept of a group algebra as follows. Let F
be a unital C*-algebra, and let S_0 be a proper subset of its states within
which one wants to keep the analysis (e.g. F is the group algebra of a discrete
group G, and S_0 is the set of states continuous w.r.t. some nondiscrete
topology of G). Then a host algebra is a C*-algebra L for which we have
embeddings of F and L into a larger C*-algebra E, such that the states on L
extend uniquely to F, and this extension defines a norm continuous affine
bijection between S_0 and the whole state space of L. The main examples (but
not the only ones) are group and covariance algebras. Here we study existence
questions of a host algebra for a given pair (F,S_0), we show that if a host
algebra exists, we can do integral decompositions of states in S_0 in terms of
other states in S_0, and we show that if one does induction of representations
via host algebras one stays within the class of representations with the right
continuity properties w.r.t. S_0. Moreover, if S_0 is a folium, then up to a
central algebra one can always construct a host algebra, but this central
algebra can be an obstruction to the existence of a host algebra. These results
should be interesting to anyone who wants to construct group algebras for
general topological groups, and they are also useful for quantum physics due to
some selection criteria for physically acceptable states.

</DOC>
<DOC>
<DOCNO> 39963 </DOCNO>
Magnetic monopole bibliography


  We present a bibliography compilation on magnetic monopoles updated to
include references till the end of year 1999. It is intended to contain nearly
all the experimental papers on the subject and only the theoretical papers
which have some specific experimental implications.

</DOC>
<DOC>
<DOCNO> 39894 </DOCNO>
Confronting classical and Bayesian confidence limits to examples


  Classical confidence limits are compared to Bayesian error bounds by studying
relevant examples. The performance of the two methods is investigated relative
to the properties coherence, precision, bias, universality, simplicity. A
proposal to define error limits in various cases is derived from the
comparison. It is based on the likelihood function only and follows in most
cases the general practice in high energy physics. Classical methods are
discarded because they violate the likelihood principle, they can produce
physically inconsistent results, suffer from a lack of precision and
generality. Also the extreme Bayesian approach with arbitrary choice of the
prior probability density or priors deduced from scaling laws is rejected.

</DOC>
<DOC>
<DOCNO> 9816 </DOCNO>
Force-distance studies with piezoelectric tuning forks below 4.2 K


  Piezoelectric quartz tuning forks have been employed as the force sensor in a
dynamic mode scanning force microscope operating at temperatures down to 1.7 K
at He-gas pressures of typically 5 mbar. An electrochemically etched tungsten
tip glued to one of the tuning fork prongs acts as the local force sensor. Its
oscillation amplitude can be tuned between a few angstroms and tens of
nanometers. Quality factors of up to 120000 allow a very accurate measurement
of small frequency shifts. Three calibration procedures are compared which
allow the determination of the proportionality constant between frequency shift
and local force gradient based on the harmonic oscillator model and on
electrostatic forces. The calibrated sensor is then used for a study of the
interaction between the tip and a HOPG substrate. Force gradient and dissipated
power can be recorded simultane-ously. It is found that during approaching the
tip to the sample considerable power starts to be dissipated although the force
gradient is still negative, i.e. the tip is still in the attractive regime.
This observation concurs with experiments with true atomic resolution which
seem to require the same tip-sample separation.

</DOC>
<DOC>
<DOCNO> 119902 </DOCNO>
Extended Extragalactic Radio Emission


  Extended radio emission and its relation to parent galaxy properties is
briefly reviewed. Our current understanding of the relation between absolute
radio and optical luminosity, radio morphology and linear size is discussed.
The impact of radio jets on dense cluster cores is discussed using M87 as an
example. Finally, the relation of AGN's to star-bursting galaxies at high
redshift is considered.

</DOC>
<DOC>
<DOCNO> 150558 </DOCNO>
The Asymptotic Groundstate of SU(3) Matrix Theory


  The asymptotic form of a SU(3) matrix theory groundstate is found by showing
that a recent ansatz for a supersymmetric wavefunction is non-trivial (i.e.
non-zero).

</DOC>
<DOC>
<DOCNO> 102097 </DOCNO>
The critical group of a directed graph


  The critical group K(G) of a directed graph G=(V,E) is the cokernel of the
transpose of the Laplacian matrix of G acting on the integer lattice Z^V. For
undirected graphs G, this has been considered by Bacher, de la Harpe, and
Nagnibeda, and by Biggs. We prove several things, among which are: K(G/p) is a
subgroup of K(G) when p is an equitable partition and G is strongly connected;
for undirected graphs, the torsion subgroup of K(G) depends only on the graphic
matroid of G; and, the `dollar game' of Biggs can be generalized to give a
combinatorial interpretation for the elements of K(G), when G is strongly
connected.

</DOC>
<DOC>
<DOCNO> 40381 </DOCNO>
A Water \v{C}erenkov Calorimeter as the Next Generation Neutrino


  We propose here a large homogeneous calorimeter as the next generation
neutrino detector for $\nu$ factories and/or conventional $\nu$ beams. The
active media is chosen to be water for obvious economical reasons. The \v
Cerenkov light produced in water is sufficient to have good energy resolution,
and the pattern recognition is realized by a modular water tank structure.
Monte Carlo simulations demonstrate that the detector performance is excellent
for identifying neutrino CC events while rejecting background events.

</DOC>
<DOC>
<DOCNO> 120829 </DOCNO>
The Globular Cluster Omega Centauri and the Oosterhoff Dichotomy


  CCD observations obtained by the OGLE team for 128 RR Lyrae variables in
Omega Cen have been analysed. The P-L and P-A plots indicate that, in addition
to fundamental (RRab) and first overtone (RRc) pulsators, the Omega Cen RR
Lyrae population seems to include second overtone (RRe) and possibly third
overtone pulsators. The mean periods derived for the RRab and RRc stars are
typical values for an Oosterhoff type II (OoII) cluster. Nevertheless, the P-A
plot plot also shows that some of the RR Lyrae variables have `Oosterhoff type
I' (OoI) characteristics. Relative luminosities derived for the RRc variables
from Fourier coefficients correlate with the observed apparent magnitudes.
Masses for the RRc stars have been calculated from Fourier coefficients. A
comparison of the derived masses for RRc stars in the four OoII clusters Omega
Cen, M15, M55 and M68 indicates that the masses of the RRc stars in M15 and M68
are almost 0.2 solar masses greater than those in the other two. Since M15 and
M68 have a high frequency of RRd stars among their first overtone pulsators,
while none have been identified in Omega Cen or M55, this suggests that the
double-mode pulsation phenomenon may be associated with mass. Among the RRc
variables in Omega Cen, the OoII variables have lower derived masses and higher
luminosities than the OoI variables. An application of the period-density law
to pairs of OoI and OoII RRab stars selected according to their position in the
P-A plot also indicates that the OoII variables in general have lower masses
and higher luminosities. These findings support the hypothesis that RR Lyrae
variables in OoII systems are evolved HB stars that spend their ZAHB phase on
the blue side of the instability strip.

</DOC>
<DOC>
<DOCNO> 117930 </DOCNO>
Measuring Cosmological Parameters from the Evolution of Cluster X-ray


  We have determined the cluster X-ray temperature function from two flux- and
redshift-limited samples of clusters. The first sample is comprised of 25
clusters with average redshift 0.05. The local temperature function derived
from it supercedes the one we previously published. Fourteen clusters with
average redshift 0.38 comprise the second sample. We perform maximum likelihood
fits of cluster evolution models to these data in order to constrain
cosmological parameters. For an open model with zero cosmological constant we
find that the density parameter is Omega_0 = 0.49+/-0.12, the rms mass density
fluctuation averaged over 8 h-1 Mpc spheres is sigma_8 = 0.72+/-0.10, and the
effective index of the mass density fluctuation spectrum on cluster scales is n
= -(1.72+/-0.34) where all errors are symmetrized at 68% confidence. The
corresponding results for the case where a cosmological constant produces a
flat universe are : 0.44+/-0.12, 0.77+/-0.15, and -(1.68+/-0.38). These results
agree with those determined from a variety of different independent methods,
including supernovae, galaxy-galaxy correlations, fluctuations in the microwave
background, gravitational lens statistics, and cluster peculiar velocities.

</DOC>
<DOC>
<DOCNO> 117762 </DOCNO>
Low Frequency Insights Into Supernova Remnants


  Low frequency observations at 330 and 74 MHz can provide new insights into
supernova remnants (SNR). We can test theoretical predictions for spectral
index variations. Nonlinear models of shock acceleration predict that the
spectra from young SNR should be slightly concave rather than power laws --
flattening toward higher energies. However, few SNR are bright and compact
enough to be studied at millimeter wavelengths, restricting studies to the
small range from 6 to 20 cm (a factor of 1.7 in electron energies).
Observations at 330 MHz increase the electron energy baseline to a factor of 4,
while providing sensitivity to larger spatial scales that are resolved out by
centimeter-wavelength interferometers. Such observations can also separate
thermal from nonthermal emission and detect excess free-free absorption
associated with cool gas in remnants. Wide field images also provide an
efficient census of both thermal and nonthermal sources over a large region.

</DOC>
<DOC>
<DOCNO> 170539 </DOCNO>
Evaluating quantum teleportation of coherent states


  We discuss the criteria for teleporting coherent states from simple
considerations about information exchange during the teleportation process.

</DOC>
<DOC>
<DOCNO> 10217 </DOCNO>
Spreading and localization of wavepackets in disordered wires in a


  We study the diffusive and localization properties of wavepackets in
disordered wires in a magnetic field. In contrast to a recent supersymmetry
approach our numerical results show that the decay rate of the steady state
changes {\em smoothly} at the crossover from preserved to broken time-reversal
symmetry. Scaling and fluctuation properties are also analyzed and a formula,
which was derived analytically only in the pure symmetry cases is shown to
describe also the steady state wavefunction at the crossover regime. Finally,
we present a scaling for the variance of the packet which shows again a smooth
transition due to the magnetic field.

</DOC>
<DOC>
<DOCNO> 119013 </DOCNO>
Dark matter caustics


  The late infall of cold dark matter onto an isolated galaxy such as our own
produces flows with definite velocity vectors at any physical point in the
galactic halo. It also produces caustics which are places where the dark matter
density is very large. The outer caustics are topological spheres whereas the
inner caustics are rings. The self-similar model of galactic halo formation
predicts that the caustic ring radii $a_n$ follow the approximate law $a_n \sim
1/n$. In a recent study of 32 extended and well-measured galactic rotation
curves, we found evidence for this law.

</DOC>
<DOC>
<DOCNO> 12035 </DOCNO>
Random Matrix Theory with Non-integer Beta-parameter


  We show that the random matrix theory with non-integer "symmetry parameter"
beta describes the statistics of transport parameters of strongly disordered
two dimensional systems.

</DOC>
<DOC>
<DOCNO> 122203 </DOCNO>
Massive and luminous YSO IRAS 05361+3539 and its environment. A study of


  Near-infrared photometry and narrow/broad-band imaging of the massive and
luminous young stellar object IRAS 05361+3539 are presented. Imaging
observations were made at Mt. Abu while the photometric data were taken from
the 2MASS. From the color-color and color-magnitude diagrams, we identified
several sources of faint Class II type and about six Class I type in the parent
molecular cloud complex. The IRAS 05361+3539 itself was seen to be a Class I
object and our images in Br$\gamma$ and H$_{2}$ lines show jets/outflows from
this object. The jet/outflow matches with the axis of CO outflow detected
earlier. The near-infrared and the IRAS far-infrared flux distribution suggests
a possible accretion disk with dust temperatures between 80 to 800K and extent
of several tens to hundreds of AU. A possible FU Orionis type of source was
detected in the cluster.

</DOC>
<DOC>
<DOCNO> 178419 </DOCNO>
Nuclear Saturation with QCD sum rules


  The scalar and vectorial self energies obtained through QCD sum rules are
introduced in the Quantum Hadrodynamics (QHD) equations. This QHD and QCD
mixing show us that the effect of the density on the coupling constants is very
small.

</DOC>
<DOC>
<DOCNO> 70990 </DOCNO>
QED radiative corrections to impact factors


  We consider the radiative corrections to the impact factors of electron and
photon. According to a generalized eikonal representation the e\bar e
scattering amplitude at high energies and fixed momentum transfers is
proportional to the electron form factor. But we show that this representation
is violated due to the presence of non-planar diagrams. One loop correction to
the photon impact factor for small virtualities of the exchanged photon is
obtained using the known results for the cross section of the e\bar e
production at photon-nuclei interactions.

</DOC>
<DOC>
<DOCNO> 12294 </DOCNO>
Quantum information processing in semiconductor nanostructures


  A major question for condensed matter physics is whether a solid-state
quantum computer can ever be built. Here we discuss two different schemes for
quantum information processing using semiconductor nanostructures. First, we
show how optically driven coupled quantum dots can be used to prepare maximally
entangled Bell and Greenberger-Horne-Zeilinger states by varying the strength
and duration of selective light pulses. The setup allows us to perform an
all-optical generation of the quantum teleportation of an excitonic state in an
array of coupled quantum dots.
 Second, we give a proposal for reliable implementation of quantum logic gates
and long decoherence times in a quantum dots system based on nuclear magnetic
resonance (NMR), where the nuclear resonance is controlled by the ground state
transitions of few-electron QDs in an external magnetic field. The dynamical
evolution of these systems in the presence of environmentally-induced
decoherence effects is also discussed.

</DOC>
<DOC>
<DOCNO> 118495 </DOCNO>
Radial Temperature Profiles of 11 Clusters of Galaxies Observed With


  We have derived azimuthally-averaged radial temperature profiles of the X-ray
gas contained within 11 clusters of galaxies with redshift z=0.03-0.2 with
BeppoSAX. Each of the 11 clusters have had their radial temperature profiles
previously determined with ASCA. We find that the temperature profiles of these
clusters are generally flat or increase slightly out to ~30% of the virial
radius, and that a decline in temperature of 14% out to 30% of the virial
radius is ruled out at the 99% confidence level. This is in accordance with a
previous ROSAT PSPC study and an ASCA study by White (1999), but in
disagreement with an ASCA study by Markevitch et al. (1998) that found on
average that cluster temperature profiles decreased significantly with radius.

</DOC>
<DOC>
<DOCNO> 69036 </DOCNO>
An infrared background--TeV gamma-ray crisis?


  We consider the implications of the recent determination of the universal
infrared background for the propagation of photons up to 20 TeV from the active
galaxy Markarian 501 as observed by HEGRA. At 20 TeV the mean free path for
photon-photon collisions on the infrared background would be much shorter than
the distance to Markarian 501, implying absorption factors of the order of
exp(-10), or greater, and consequently an excessive power output for this
active galaxy. Possible solutions of this problem are discussed.

</DOC>
<DOC>
<DOCNO> 120666 </DOCNO>
Science with SIRTF - Some Examples


  The Space InfraRed Telescope Facility (SIRTF) is a space-borne,
cryogenically-cooled infrared observatory capable of studying objects ranging
from our Solar System to the distant reaches of the Universe. SIRTF is the
final element in NASA's Great Observatories Program, and an important component
of its Origins Program. The intent of this paper is to summarize the most
important parameters of the observatory and its scientific instruments and to
present three typical examples of scientific areas where SIRTF will have a
significant impact. These examples of ``nearby'' targets -- brown dwarf
surveys, protostellar disks, and massive young clusters -- have been selected
in regard to the main topics of this conference.

</DOC>
<DOC>
<DOCNO> 121139 </DOCNO>
Scattering of energetic particles by anisotropic magnetohydrodynamic


  Scattering rates for a Goldreich-Sridhar (GS) spectrum of anisotropic,
incompressible, magnetohydrodynamic turbulence are calculated in the
quasilinear approximation. Because the small-scale fluctuations are constrained
to have wave vectors nearly perpendicular to the background magnetic field,
scattering is too weak to provide either the mean free paths commonly used in
Galactic cosmic-ray propagation models or the mean free paths required for
acceleration of cosmic rays at quasi-parallel shocks. Where strong pitch-angle
scattering occurs, it is due to fluctuations not described by the GS spectrum,
such as fluctuations generated by streaming cosmic rays.

</DOC>
<DOC>
<DOCNO> 12336 </DOCNO>
Current Induced Magnetization Switching in Small Domains of Different


  Several recent experimental studies have confirmed the possibility of
switching the magnetization direction in the small magnetic domains by pumping
large spin-polarized currents through them. On the basis of equations proposed
by J.Slonczewski for the case when magnetization of the domains is almost
uniform, we analyze the stability and switching for two types of magnetic and
shape anisotropies of a magnetic domain in a nanowire and find qualitatively
different behavior, including different shapes of bistable regions. Our study
is analytic as opposed to recent numeric work. Assumed anisotropies can be
realized in experiments and our predictions can be used to experimentally test
the theory of spin-transfer torques. Such test would be especially interesting
since alternative approaches are discussed in the literature.

</DOC>
<DOC>
<DOCNO> 169948 </DOCNO>
Hidden Variables or Positive Probabilities?


  Despite claims that Bell's inequalities are based on the Einstein locality
condition, or equivalent, all derivations make an identical mathematical
assumption: that local hidden-variable theories produce a set of
positive-definite probabilities for detecting a particle with a given spin
orientation. The standard argument is that because quantum mechanics assumes
that particles are emitted in a superposition of states the theory cannot
produce such a set of probabilities. We examine a paper by Eberhard, and
several similar papers, which claim to show that a generalized Bell inequality,
the CHSH inequality, can be derived solely on the basis of the locality
condition, without recourse to hidden variables. We point out that these
authors nonetheless assumes a set of positive-definite probabilities, which
supports the claim that hidden variables or "locality" is not at issue here,
positive-definite probabilities are. We demonstrate that quantum mechanics does
predict a set of probabilities that violate the CHSH inequality; however these
probabilities are not positive-definite. Nevertheless, they are physically
meaningful in that they give the usual quantum-mechanical predictions in
physical situations. We discuss in what sense our results are related to the
Wigner distribution.

</DOC>
<DOC>
<DOCNO> 71115 </DOCNO>
At the edge of nuclear stability: nonlinear quantum amplifiers


  We show that nuclear states lying at the edge of stability may show
enormously enhanced response to small perturbations. For example, a 0.1% change
in the strength of the strong nucleon-nucleon interaction can cause almost a
hundred times bigger change in the resonance energy of the 0+_2 state of 12C.

</DOC>
<DOC>
<DOCNO> 40534 </DOCNO>
Hybrid Pixel Detector Development for the Linear Collider Vertex Tracker


  In order to fully exploit the physics potential of the future high energy
e+e- linear collider, a Vertex Tracker able to provide particle track
extrapolation with very high resolution is needed. Hybrid Si pixel sensors are
an attractive technology due to their fast read-out capabilities and radiation
hardness. A novel pixel detector layout with interleaved cells has been
developed to improve the single point resolution. Results of the
characterisation of the first processed prototypes by electrostatic
measurements and charge collection studies are discussed.

</DOC>
<DOC>
<DOCNO> 178414 </DOCNO>
The reaction $^2H(\gamma,\pi^0)np$ in the threshold region


  Neutral pion photoproduction on the deuteron in the inelastic channel is
studied in the threshold region from 142 to 160 MeV. The calculation is based
on the use of the diagrammatic approach. Contributions from the pole diagrams,
one-loop diagrams both with $n$-$p$ and $\pi$-$N$ rescattering as well as
two-loop diagrams with simultaneous inclusion of these rescattering mechanisms
are taken into account. We have found a reasonable agreement with a very simple
calculation by J.C. Bergstrom et al. [Phys. Rev. C 57 (1998) 3203]. It is shown
that the `effective' electric dipole deuteron amplitude $E_d$ is negative in
agreement with a prediction of ChPT. We conclude that a deviation of about 20%
from a ChPT prediction for $E_d$ discovered in an experiment on coherent
$\pi^0$ photoproduction off the deuteron cannot be attributed to inadequate
estimates of inelastic channel contributions. We suggest that $\pi$-$N$
rescattering is responsible for the deviation of the free-nucleon $p_1$
threshold amplitude from the value measured in that experiment

</DOC>
<DOC>
<DOCNO> 99647 </DOCNO>
On the eigenstates of the elliptic Calogero-Moser model


  It is known that the trigonometric Calogero-Sutherland model is obtained by
the trigonometric limit (\tau \to \sqrt{-1} \infty) of the elliptic
Calogero-Moser model, where (1,\tau) is a basic period of the elliptic
function. We show that for all square-integrable eigenstates and eigenvalues of
the Hamiltonian of the Calogero-Sutherland model, if \exp (2\pi \sqrt{-1} \tau
) is small enough then there exist square-integrable eigenstates and
eigenvalues of the Hamiltonian of the elliptic Calogero-Moser model which
converge to the ones of the Calogero-Sutherland model for the 2-particle and
the coupling constant l is positive integer cases and the 3-particle and l=1
case. In other words, we justify the regular perturbation with respect to the
parameter \exp (2\pi \sqrt{-1} \tau). With some assumptions, we show analogous
results for N-particle and l is positive integer cases.

</DOC>
<DOC>
<DOCNO> 100948 </DOCNO>
Harmonic analysis with respect to heat kernel measure


  I review certain results in harmonic analysis for systems whose configuration
space is a compact Lie group. The results described involve a heat kernel
measure, which plays the same role as a Gaussian measure on Euclidean space.
The main constructions are group analogs of the Hermite expansion, the
Segal-Bargmann transform, and the Taylor expansion. The results are related to
geometric quantization, to stochastic analysis, and to the quantization of
1+1-dimensional Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 116382 </DOCNO>
Generalized oscillator strength for Na 3s-3p transition


  Generalized oscillator strengths (GOS's) for the Na $3s -3p$ transition have
been investigated using the spin-polarized technique of the random phase
approximation with exchange (RPAE) and the first Born approximation (FBA),
focussing our attention on the position of the minimum. Intershell correlations
are found to influence the position of the minimum significantly, but hardly
that of the maximum. The RPAE calculation predicts for the first time the
positions of the minimum and maximum at momentum transfer, $K$ values of 1.258
a.u. and 1.61 a.u., respectively. The former value is within the range of
values extracted from experimental measurements, $K=1.0-1.67$ a.u.. We
recommend careful experimental search for the minimum around the predicted
value for confirmation.

</DOC>
<DOC>
<DOCNO> 68493 </DOCNO>
New Physics behind the Standard Model's door?


  We review the main reasons pushing us beyond the SM and we argue in favor of
new physics at the electroweak scale (hence experimentally accessible at
present or near-future machines). We focus on the appealing possibility that
such new physics is given by a supersymmetric (SUSY) extension of the SM. We
discuss the minimal case, Constrained Minimal Supersymmetric SM, and more
general (maybe more natural) cases where some of the drastic assumptions of the
CMSSM are dropped. In particular, in these lectures we focus on CP violation
and its relation to flavor physics in the SUSY context. CP constrains the
low-energy SUSY extensions of the SM, but, at the same time, it provides new
powerful tool for indirect SUSY searches.

</DOC>
<DOC>
<DOCNO> 12107 </DOCNO>
Quantum Fluctuations in the Frustrated Antiferromagnet Sr_2Cu_3O_4Cl_2


  Sr_2Cu_3O_4Cl_2 is an antiferromagnet consisting of weakly coupled CuO planes
which comprise two weakly interacting antiferromagnetic subsystems, I and II,
which order at respective temperatures T_I \approx 390K and T_{II} \approx 40K.
Except asymptotically near the ordering temperature, these systems are good
representations of the two-dimensional quantum spin 1/2 Heisenberg model. For
T< T_{II} there are four low-energy modes at zero wave vector, three of whose
energies are dominated by quantum fluctuations. For T_{II} < T < T_I there are
two low energy modes. The mode with lower energy is dominated by quantum
fluctuations. Our calculations of the energies of these modes (including
dispersion for wave vectors perpendicular to the CuO planes) agree extremely
well with the experimental results of inelastic neutron scattering (in the
accompanying paper) and for modes in the sub meV range observed by electron
spin resonance. The parameters needed to describe quantum fluctuations are
either calculated here or are taken from the literature. These results show
that we have a reasonable qualitative understanding of the band structure of
the lamellar cuprates needed to calculate the anisotropic exchange constants
used here.

</DOC>
<DOC>
<DOCNO> 120659 </DOCNO>
On the Relation Between Radio and Non-Radio Elliptical Galaxies


  Empirical evidence suggests that elliptical galaxies hosting a radio source
may not be different from normal non-radio ellipticals. To test this
possibility, we use Monte Carlo simulations to reproduce the distribution of
radio galaxies in the radio-optical luminosity plane. The input parameters of
the simulation are the optical luminosity function (LF) of ellipticals and the
radio LF of radio galaxies, linked by a function giving the probability for an
elliptical to be a radio galaxy.
  Simulations reproduce the observations well, supporting unification of radio
and non-radio ellipticals, provided that the probability of an elliptical
hosting a radio source is proportional to the square of its optical luminosity.
  The difference of 0.5 magnitudes in average optical luminosity between FRI
and FRII radio galaxies is also explained in this framework.

</DOC>
<DOC>
<DOCNO> 178560 </DOCNO>
Pairing Interaction in N=Z Nuclei with Half-filled High-j Shell


  The role of L=0 pairing interactions (both T=0 and T=1) in three selected
bands with the total isospin T=0 in 22Na, 48Cr and 90Rh nuclei is discussed in
the spherical shell model. These bands were selected requiring termination in a
most unfavourable way. The investigated effects coming from pairing
interactions include the change of nuclear wavefunction, quadrupole properties
and state energy. To follow the gradual change of nuclear properties, the
investigation is performed in a perturbative approach by defining the
Hamiltonian with a variable content of the pairing interaction. It is shown
that the pairing does not affect the quadrupole properties, if the energy
distance to other close lying states is large. The calculated pairing energy is
shown to have a similar spin dependence in these three bands. In addition, the
influence of the model space as well as of the residual interaction on the
derived pairing energy is discussed.

</DOC>
<DOC>
<DOCNO> 151602 </DOCNO>
The Akulov-Volkov Lagrangian, Symmetry Currents and Spontaneously Broken


  A generalization of the Akulov-Volkov effective Lagrangian governing the self
interactions of the Nambu-Goldstone fermions associated with spontaneously
broken extended supersymmetry as well as their coupling to matter is presented
and scrutinized. The resulting currents associated with R-symmetry,
supersymmetry and space-time translations are constructed and seen to form a
supermultiplet structure.

</DOC>
<DOC>
<DOCNO> 123161 </DOCNO>
The New Paradigm: Novel, Virtual Observatory Enabled Science


  A virtual observatory will not only enhance many current scientific
investigations, but it will also enable entirely new scientific explorations
due to both the federation of vast amounts of multiwavelength data and the new
archival services which will, as a necessity, be developed. The detailing of
specific science use cases is important in order to properly facilitate the
development of the necessary infrastructure of a virtual observatory. The
understanding of high velocity clouds is presented as an example science use
case, demonstrating the future synergy between the data (either catalog or
images), and the desired analysis in the new paradigm of a virtual observatory.

</DOC>
<DOC>
<DOCNO> 8317 </DOCNO>
Quantum computation by optically coupled steady atoms/quantum-dots


  We present a model for quantum computation using n steady 3-level atoms or
3-level quantum dots, kept inside a quantum electro-dynamics (QED) cavity. Our
model allows one-qubit operations and the two-qubit controlled-NOT gate as
required for universal quantum computation. The n quantum bits are described by
two energy levels of each atom/dot. An external laser and n separate pairs of
electrodes are used to address a single atom/dot independent of the others, via
Stark effect. The third level of each system and an additional common-mode
qubit (a cavity photon) are used for realizing the controlled-NOT operation
between any pair of qubits. Laser frequency, cavity frequency, and energy
levels are far off-resonance, and they are brought to resonance by modifying
the energy-levels of a 3-level system using the Stark effect, only at the time
of operation.

</DOC>
<DOC>
<DOCNO> 12051 </DOCNO>
The electron gas with a strong pairing interaction: Three particle


  We derive simplified Faddeev type equations for the three particle T-matrix
which are valid in the Hubbard model where only electrons with opposite spins
interact. Using the approximation of dynamical mean field theory these
equations are partially solved numerically for the attractive Hubbard model. It
is shown that the three particle T-matrix contains a term vanishing $\sim T^2$
at the Thouless (or BCS) instability where the two-particle T-matrix diverges.
Based on the three particle term we further derive the low density - strong
coupling extension for the two-particle vertex function. We therefore
understand our equations as a step towards a systematic low density expansion
from the weak coupling BCS theory towards the stronger coupling limit.

</DOC>
<DOC>
<DOCNO> 116349 </DOCNO>
Cosmological Models with Some Variable Constant


  Various models are under consideration with metric type flat FRW whose
energy-momentum tensor is described by a perfect fluid whose generic equation
state and taking into account the conservation principle, but considering some
of the constants as variable. A set of solutions through dimensional analysis
is trivially found. The numeric calculations carried out show that the results
obtained are not discordant with those presently observed for cosmological
parameters. However, the model seems irreconcilable with electromagnetic and
quantum quantities. This makes us think that we are working with faulty
hypothesis from the start

</DOC>
<DOC>
<DOCNO> 119791 </DOCNO>
Galactosynthesis: Halo Histories, Star Formation, and Disks


  We investigate the effects of a variety of ingredients that must enter into a
realistic model for disk-galaxy formation, focusing primarily on the
Tully-Fisher (TF) relation and its scatter in several wavebands. Our main
findings are: (a) the slope, normalization, and scatter of the TF relation
across various wavebands is determined {\em both} by halo properties and star
formation in the disk; (b) TF scatter owes primarily to the spread in formation
redshifts. The scatter can be measurably reduced by chemical evolution, and
also in some cases by the weak anti-correlation between peak height and spin;
(c) multi-wavelength constraints can be important in distinguishing between
models which appear to fit the TF relation in I or K; (d) successful models
seem to require that the bulk of disk formation cannot occur too early (z>2) or
too late (z<0.5), and are inconsistent with high values of $\Omega_0$; (e) a
realistic model with the above ingredients can reasonably reproduce the
observed z=0 TF relation in {\em all} bands (B, R, I, and K). It can also
account for the z=1 B-band TF relation and yield rough agreement with the local
B and K luminosity functions and B-band surface-brightness--magnitude relation.
The remarkable agreement with observations suggests that the amount of gas that
is expelled or poured into a disk galaxy must be small, and that the specific
angular momentum of the baryons must roughly equal that of the halo; there is
little room for angular momentum transfer. In an appendix we present analytic
fits to stellar-population synthesis models.

</DOC>
<DOC>
<DOCNO> 8423 </DOCNO>
Circulating electrons, superconductivity, and the Darwin-Breit


  The importance of the Darwin-Breit interaction between electrons in solids at
low temperatures is investigated. The model problem of particles on a circle is
used and applied to mesoscopic metal rings in their normal state. The London
moment formula for a rotating superconducting body is used to calculate the
number, $N$, of superconducting electrons in the body. This number is found to
be equal to the size, $R$, of the system divided by the classical electron
radius, i.e. $N=Rmc^2/e^2$. The Darwin-Breit interaction gives a natural
explanation for this relation from first principles. It also is capable of
electron pairing. Collective effects of this interaction require a minimum of
two dimensions but electron pairing is enhanced in one-dimensional systems.

</DOC>
<DOC>
<DOCNO> 117475 </DOCNO>
The Stellar Content of the Halo of NGC 5907 from Deep HST NICMOS Imaging


  We present H-band images obtained with NICMOS of a field 75'' (5kpc) above
the plane of the disk of the edge-on spiral galaxy NGC 5907. Ground-based
observations have shown that NGC 5907 has a luminous halo with a shallow radial
profile between 4 and 8 kpc that roughly traces the dark matter distribution of
the galaxy deduced from its rotation curve. Our NICMOS observations were
designed to resolve bright giants in the halo of NGC 5907 to constrain its
stellar composition with the goal of understanding its nature and origin. More
than 100 stars are expected in the NICMOS images if the dwarf-to-giant ratio in
the halo of NGC 5907 is consistent with that expected from standard stellar
initial mass functions, and if ground-based estimates of the distance to NGC
5907 and the integrated colors of its halo are correct. Instead we observe only
one candidate giant star. This apparent discrepancy can be resolved by assuming
either a significantly larger distance than suggested by several studies, or a
halo metallicity much lower than suggested by ground-based colors and as low as
metal-poor Galactic globular clusters. If previous distance and halo color
estimates for NGC 5907 are correct, our NICMOS results suggest that its
extended light is composed of stars that formed with an initial mass function
different than that observed locally, leading to a much higher ratio of dwarfs
to giants. We describe how these three possible explanations for the absence of
bright giants in our NICMOS images of the halo of NGC 5907 might be constrained
by future observations.

</DOC>
<DOC>
<DOCNO> 80953 </DOCNO>
f_B for Various Actions : Approaching the Continuum Limit with Dynamical


  We present results for pseudoscalar decay constants of heavy-light mesons
using both quenched and N_f = 2 dynamical fermion configurations. A variety of
fermion actions is investigated : Wilson, nonperturbative clover, and fat-link
clover. For heavy quarks the Fermilab formalism is applied. In the quenched
approximation, results with the nonperturbatively improved clover action of the
Alpha collaboration allow us to study the systematic error of the continuum
extrapolation from the Wilson action. In addition, we use quenched
configurations to explore the effects of fattening. The lessons from the
quenched analyses are then applied to data with dynamical fermions, where both
Wilson and fat-link clover actions have been used. This allows us to attempt a
continuum extrapolation of the dynamical results.

</DOC>
<DOC>
<DOCNO> 120350 </DOCNO>
MBM12: A Younger Version of the TW Hydrae Association?


  We present optical and infrared photometry of stars near the MBM 12 dark
cloud. The optical data indicate that there are about 40 candidate pre-main
sequence stars in the same area currently occupied by eight bona-fide PMS
stars. Analysis of 2MASS data suggests that 60% of PMS candidates have been
detected. Some of these show evidence of optically thick disks. Our study of
the 2MASS data also reveals a large enhancement of sources within the MBM 12
cloud, indicating that it is still actively forming stars.

</DOC>
<DOC>
<DOCNO> 70743 </DOCNO>
Explanation on Negative Mass-Square of Neutrinos


  It has been known for many years that the measured mass-square of neutrino is
probably negative. For solving this puzzle, we have further investigated the
hypothesis that neutrinos are superluminal fermions. A new Dirac-type equation
is proposed and a tachyonic quantum theory is briefly discussed. This equation
is equivalent to two Weyl equations coupled together via nonzero mass while
respecting the maximum parity violation, and it reduces to one Weyl equation
when the neutrino mass becomes zero.

</DOC>
<DOC>
<DOCNO> 120202 </DOCNO>
BeppoSAX - ROSAT PSPC observations of the Shapley Supercluster: A3562


  We present a combined analysis of the BeppoSAX and ROSAT PSPC observation of
the cluster of galaxies A3562, a massive member of the core of the Shapley
Supercluster. With a complex and interacting structure composed from two groups
of galaxies and A3558 to the West, the surface brightness of A3562 shows excess
in the sectors to East and South when compared with an azimuthally averaged
model of the emission. The emission tends to be flatter, and the distribution
of the gas broader, along the merging axis and in opposition to the two groups.
We present the first determination of the gradients of the gas temperature and
metallicity for a cluster in the Shapley region at large distance from cluster
center. From an analysis of the BeppoSAX data in annuli and sectors, we observe
both the profiles to be flat within 8 arcmin (0.62 Mpc), with an
emission-weighted values of kT = 5.1+-0.2 keV and Z = 0.39+-0.05 Zsolar. The
value of the temperature is consistent with recent ASCA measurements and is
significantly higher than previous estimates obtained from ROSAT and EXOSAT. We
discuss the possible reasons of this disagreement. Between 8 and 20 arcmin, the
plasma temperature declines to about 3.2 keV. When a polytropic profile is used
to represent the gas temperature profile, the best fit polytropic index is
1.16+-0.03. These results imply a total mass within the virial radius of 3.9
(+-0.4) 10^14 h_50^-1 Msolar, between 40 and 80 per cent lower than the optical
estimate, and a gas mass fraction of about 30 per cent.

</DOC>
<DOC>
<DOCNO> 116665 </DOCNO>
Enhanced Pitch Angle Diffusion due to Electron-Whistler Interactions


  During periods of increased magnetospheric activity, whistler wave emissions
have been observed with increased wave amplitudes. We consider a pitch angle
diffusion mechanism that is shown to scale with whistler wave amplitude and
hence is 'switched on' during these periods of intense activity.
  We consider the interaction between relativistic electrons and two oppositely
directed, parallel propagating whistler mode waves. We show that for intense
whistlers this process is stochastic and results in strong electron pitch angle
diffusion.
  We show that the interaction is rapid, occur on timescales of the order of
tens of electron gyroperiods and that the interaction is sensitive to wave
amplitude, wave frequency and electron energy.

</DOC>
<DOC>
<DOCNO> 11628 </DOCNO>
Mutagenesis and Metallic DNA


  Positions of protons in DNA hydrogen bonds are fundamental for the fidelity
of the replication process. Because the hydrogen bond is partially covalent the
electronic structure of DNA plays an important role in the replication process.
Current studies of electron transfer in DNA have shown that simple pictures
based on independent electron physics are not sufficient to account for the
experimental data. In this paper we propose a model for electron-proton
interaction in DNA and its relationship to mutagenesis. We argue that mutations
will be more frequent in DNA sequences where electron delocalization occurs. To
test our theory we calculate the heat capacity of DNA at low temperatures and
compare with the available experimental data in hydrated DNA. We find that our
model is in good agreement with the data. We also propose new measurements of
infrared absorption which would further test our ideas.

</DOC>
<DOC>
<DOCNO> 11249 </DOCNO>
Low frequency, low temperature properties of the spin-boson problem


  Low temperature and low frequency properties of a spin-boson model are
investigated within a super operator and Liouville space formulation. The
leading contributions are identified with the help of projection operators
projecting onto the equilibrium state. The quantities of interest are expressed
in terms of weighted bath propagators and static linear and nonlinear
susceptibilities. In particular the generalized Shiba relation and Wilson ratio
are recovered.

</DOC>
<DOC>
<DOCNO> 123290 </DOCNO>
Splitting of the Dipole and Spin-Dipole Resonances


  Cross sections for the 90,92,94Zr(p,n) reactions were measured at energies of
79.2 and 119.4 MeV. A phenomenological model was developed to describe the
variation with bombarding energy of the position of the L=1 peak observed in
these and other (p,n) reactions. The model yields the splitting between the
giant dipole and giant spin dipole resonances. Values of these splittings are
obtained for isotopes of Zr and Sn and for 208Pb.

</DOC>
<DOC>
<DOCNO> 116942 </DOCNO>
A Real-Time Energy Monitor System for the Ipns Linac


  Injected beam energy and energy spread are critical parameters affecting the
performance of our rapid cycling synchrotron (RCS). A real-time energy
monitoring system is being installed to examine the H- beam out of the Intense
Pulsed Neutron Source (IPNS) 50 MeV linac. The 200 MHz Alvarez linac serves as
the injector for the 450 MeV IPNS RCS. The linac provides an 80 ms macropulse
of approximately 3x1012 H- ions 30 times per second for coasting-beam injection
into the RCS. The RCS delivers protons to a heavy-metal spallation neutron
target for material science studies. Using a number of strip-line beam position
monitors (BPMs) distributed along the 50 MeV transport line from the linac to
the RCS, fast signals from the strip lines are digitized and transferred to a
computer which performs an FFT. Corrections for cable attenuation and
oscilloscope bandwidth are made in the frequency domain. Rectangular pulse
train phasing (RPTP) is imposed on the spectra prior to obtaining the inverse
transform (IFFT). After the IFFT, the reconstructed time-domain signal is
analyzed for pulse width as it progresses along the transport line.
Time-of-flight measurements of the BPM signals provide beam energy. Finally,
using the 3-size measurement technique, the longitudinal emittance and energy
spread of the beam are determined.

</DOC>
<DOC>
<DOCNO> 84780 </DOCNO>
A Natural Renormalization of the One-Loop Effective Action for scalar


  In a previous paper \cite{gareta1}, it has been shown that the negative norm
states necessarily appear in a covariant quantization of the minimally coupled
scalar field in de Sitter space, and their presence eliminates any ultraviolet
and infrared divergence \cite{ta3}. It is possible to extend this method to the
interacting quantum field in Minkowski space-time ($\lambda\phi^4$ theory), and
this again yields a natural renormalization procedure \cite{ta4}. In this paper
we use this method for calculating the one-loop effective action for scalar
field in a general curved space-time. It is found that any divergence does not
appear and it is not needed to change the Einstein's field equation in view of
divergence elimination.

</DOC>
<DOC>
<DOCNO> 70268 </DOCNO>
B_{c} meson and the light-heavy quarkonium spectrum


  We compute the c \bar{b} spectrum from a first principle Salpeter equation
obtained in a preceding paper. For comparison we report also the heavy-light
quarkonium spectrum and the hyperfine separations previously presented only in
a graphical form. Notice that all results are parameter free.

</DOC>
<DOC>
<DOCNO> 8511 </DOCNO>
Quantum Tunneling of Magnetization in Molecular Complexes with Large


  We review the present state of theory and experiments on the quantum
tunneling of magnetization in mesoscopic spin systems. Most attention is paid
to the relaxation of magnetization in the molecular complexes Mn12 and Fe8. The
role of the thermostat (phonons, nuclear spins, dipolar fields) is studied.

</DOC>
<DOC>
<DOCNO> 178567 </DOCNO>
Application of realistic effective interactions to the structure of the


  We calculate the low-lying spectra of the zirconium isotopes Z=40 with
neutron numbers from N=52 to N=60 using the 1p1/20g9/2 proton and
2s1d0g7/20h11/2 neutron sub-shells to define the model space. Effective
proton-proton, neutron--neutron and proton-neutron interactions have been
derived using 88Sr as closed core and employing perturbative many-body
techniques. The starting point is the nucleon-nucleon potential derived from
modern meson exchange models. The comprehensive shell-model calculation
performed in this work provides a qualitative reproduction of essential
properties such as the sub-shell closures in 96Zr and 98Zr.

</DOC>
<DOC>
<DOCNO> 80946 </DOCNO>
Monopoles, Vortices and Confinement is SU(3) Lattice Gauge Theory


  We present results for the heavy quark potential computed in SU(3) from
magnetic monopoles and from center vortices. The monopoles are identified after
fixing SU(3) lattice configurations to the maximal abelian gauge. The center
vortices are identified after using an indirect center gauge fixing scheme
which we describe for SU(3). Z(3) center vortices are extracted and used to
compute the potential. The values of the string tensions from monopoles and
vortices are compared to the full SU(3) string tension.

</DOC>
<DOC>
<DOCNO> 152237 </DOCNO>
Symmetry Origin of Nonlinear Monopole


  We revisit the non-linear BPS equation: the Dirac monopole of the Born-Infeld
theory in the B-field background. The rotation used in our previous papers to
discuss the scalar field by transforming the BPS equation into a linear one is
extended to the case of gauge field. We also find that this transformation is a
symmetry of the action. Moreover using the Legendre-dual formalism we present a
simple expression of the BPS equation.

</DOC>
<DOC>
<DOCNO> 119843 </DOCNO>
VLT-ISAAC near-IR Spectroscopy of ISO selected Hubble Deep Field South


  We report the results of near-infrared VLT-ISAAC spectroscopy of a sample of
12 galaxies at z = 0.4-1.4, drawn from the ISOCAM survey of the Hubble Deep
Field South. We find that the rest frame R-band spectra of the ISOCAM galaxies
resemble those of powerful dust-enshrouded starbursts. Halpha emission is
detected in 11 out of 12 objects down to a flux limit of 7x10^(-17) erg/cm^2/s,
corresponding to a luminosity limit of 10^41 erg/s at z = 0.6, (for an Ho = 50
and Omega = 0.3 cosmology). From the Halpha luminosities in these galaxies we
derive estimates of the star formation rate in the range 2--50 Mo/yr for
stellar masses 1--100 Mo. The raw Halpha-based star formation rates are an
order of magnitude or more lower than SFR(FIR) estimates based on ISOCAM LW3
fluxes. If the Halpha emission is corrected for extinction the median offset is
reduced to a factor of 3. The sample galaxies are part of a new population of
optically faint but infrared--luminous active starburst galaxies, which are
characterized by an extremely high rate of evolution with redshift up to z~1.5
and expected to contribute significantly to the cosmic far-IR extragalactic
background.

</DOC>
<DOC>
<DOCNO> 70182 </DOCNO>
Vacuum properties in the presence of quantum fluctuations of the quark


  The quantum fluctuations of the quark condensate are calculated using a
regulated Nambu Jona-Lasinio model. The corresponding quantum fluctuations of
the chiral fields are compared to those which are predicted by an
''equivalent'' sigma model. They are found to be large and comparable in size
but they do not restore chiral symmetry. The restoration of chiral symmetry is
prevented by an ''exchange term'' of the pion field which does not appear in
the equivalent sigma model. A vacuum instability is found to be dangerously
close when the model is regulated with a sharp 4-momentum cut-off.

</DOC>
<DOC>
<DOCNO> 40060 </DOCNO>
Prompt muon contribution to the flux underwater


  We present high energy spectra and zenith-angle distributions of the
atmospheric muons computed for the depths of the locations of the underwater
neutrino telescopes. We compare the calculations with the data obtained in the
Baikal and the AMANDA muon experiments. The prompt muon contribution to the
muon flux underwater due to recent perturbative QCD-based models of the charm
production is expected to be observable at depths of the large underwater
neutrino telescopes. This appears to be probable even at rather shallow depths
(1-2 km), provided that the energy threshold for muon detection is raised above
$\sim 100$ TeV.

</DOC>
<DOC>
<DOCNO> 12811 </DOCNO>
Phase Transitions of Hard Disks in External Periodic Potentials: A Monte


  The nature of freezing and melting transitions for a system of hard disks in
a spatially periodic external potential is studied using extensive Monte Carlo
simulations. Detailed finite size scaling analysis of various thermodynamic
quantities like the order parameter, its cumulants etc. are used to map the
phase diagram of the system for various values of the density and the amplitude
of the external potential. We find clear indication of a re-entrant liquid
phase over a significant region of the parameter space. Our simulations
therefore show that the system of hard disks behaves in a fashion similar to
charge stabilized colloids which are known to undergo an initial freezing,
followed by a re-melting transition as the amplitude of the imposed, modulating
field produced by crossed laser beams is steadily increased. Detailed analysis
of our data shows several features consistent with a recent dislocation
unbinding theory of laser induced melting.

</DOC>
<DOC>
<DOCNO> 178723 </DOCNO>
Nuclear equation of state at high density and the properties of neutron


  We discuss the relativistic nuclear equation of state (EOS) using a
relativistic transport model in heavy-ion collisions. From the baryon flow for
$Au + Au$ systems at SIS to AGS energies and above we find that the strength of
the vector potential has to be reduced moderately at high density or at high
relative momenta to describe the flow data at 1-10 A GeV. We use the same
dynamical model to calculate the nuclear EOS and then employ this to calculate
the gross structure of the neutron star considering the core to be composed of
neutrons with an admixture of protons, electrons, muons, sigmas and lambdas at
zero temperature. We then discuss these gross properties of neutron stars such
as maximum mass and radius in contrast to the observational values.

</DOC>
<DOC>
<DOCNO> 150427 </DOCNO>
Pre-Big Bang Cosmology and Quantum Fluctuations


  The quantum fluctuations of a homogeneous, isotropic, open pre-big bang model
are discussed. By solving exactly the equations for tensor and scalar
perturbations we find that particle production is negligible during the
perturbative Pre-Big Bang phase.

</DOC>
<DOC>
<DOCNO> 10774 </DOCNO>
The commensurate-disordered phase transition in 2D classical ATNNI model


  The classical two-dimensional anisotropic triangular nearest-neighbor Ising
(ATNNI) model is studied by the density matrix renormalization group (DMRG)
technique when periodic boundary conditions are imposed. Applying the
finite-size scaling to the DMRG results a commensurate-disordered (C-D) phase
transition line as well as temperature and magnetic critical exponents are
calculated. We conclude that the (C-D) phase transition in the ATNNI model
belongs to the same universality class as the ordered-disordered phase
transition of the Ising model.

</DOC>
<DOC>
<DOCNO> 67692 </DOCNO>
ISAJET 7.48: A Monte Carlo Event Generator for $pp$, $\bar pp$, and


  ISAJET is a Monte Carlo program which simulates $pp$, $\bar pp$ and $e^+e^-$
interactions at high energies. This document summarizes the physics underlying
the program and describes how to use it. Version~7.48 includes several new
features. Anomaly Mediated SUSY Breaking (AMSB) models and right-handed
sneutrinos have been added; the latter play a role, e.g., in inverted hierarchy
models. A new process generating $Z+\hbox{2 jets}$ based on the Helas library
and MadGraph has been added. Another new process generating Kaluza-Klein
gravitons in models with extra dimensions has been added.

</DOC>
<DOC>
<DOCNO> 84716 </DOCNO>
Making Clean Energy with a Kerr Black Hole: a Tokamak Model for


  In this paper we present a model for making clean energy with a Kerr black
hole. Consider a Kerr black hole with a dense plasma torus spinning around it.
A toroidal electric current flows on the surface of the torus, which generates
a poloidal magnetic field outside the torus. On the surface of the tours the
magnetic field is parallel to the surface. The closed magnetic field lines
winding around the torus compress and confine the plasma in the torus, as in
the case of tokamaks. Though it is unclear if such a model is stable, we look
into the consequences if the model is stable. If the magnetic field is strong
enough, the baryonic contamination from the plasma in the torus is greatly
suppressed by the magnetic confinement and a clean magnetosphere of
electron-positron pairs is built up around the black hole. Since there are no
open magnetic field lines threading the torus and no accretion, the power of
the torus is zero. If some magnetic field lines threading the black hole are
open and connect with loads, clean energy can be extracted from the Kerr black
hole by the Blandford-Znajek mechanism.
  The model may be relevant to gamma-ray bursts. The energy in the Poynting
flux produced by the Blandford-Znajek mechanism is converted into the kinetic
energy of the electron-positron pairs in the magnetosphere around the black
hole, which generates two oppositely directed jets of electron-positron pairs
with super-high bulk Lorentz factors. The jets collide and interact with the
interstellar medium, which may produce gamma-ray bursts and the afterglows.

</DOC>
<DOC>
<DOCNO> 72219 </DOCNO>
Creation of large spatial fluctuations in neutrino asymmetry by neutrino


  We consider active-sterile neutrino oscillations in the early universe in an
inhomogeneous isocurvature background. We show that very small initial baryonic
seed-inhomogeneities can trigger a growth of very large amplitude spatial
fluctuations in lepton asymmetry. Domains of varying asymmetry are observed to
persist for a long time despite dissipative effects. The space dependent
asymmetry profiles give rise to MSW-resonances within the domain boundaries,
enhancing dramatically the equilibration of the sterile neutrino species.
According to our one-dimensional toy-model, the effect is so strong that almost
the entire parameter space where exponential growth of asymmetry occurs would
be ruled out by nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 117782 </DOCNO>
The Elliptical Galaxy formerly known as the Local Group: Merging the


  Prompted by a new catalogue of M31 globular clusters, we have collected
together individual metallicity values for globular clusters in the Local
Group. Although we briefly describe the globular cluster systems of the
individual Local Group galaxies, the main thrust of our paper is to examine the
collective properties. In this way we are simulating the dissipationless merger
of the Local Group, into presumably an elliptical galaxy. Such a merger is
dominated by the Milky Way and M31, which appear to be fairly typical examples
of globular cluster systems of spiral galaxies.
  The Local Group `Elliptical' has about 700 +/- 125 globular clusters, with a
luminosity function resembling the `universal' one. The metallicity
distribution has peaks at [Fe/H] ~ -1.55 and -0.64 with a metal-poor to
metal-rich ratio of 2.5:1. The specific frequency of the Local Group Elliptical
is initially about 1 but rises to about 3, when the young stellar populations
fade and the galaxy resembles an old elliptical. The metallicity distribution
and stellar population corrected specific frequency are similar to that of some
known early type galaxies. Based on our results, we briefly speculate on the
origin of globular cluster systems in galaxies.

</DOC>
<DOC>
<DOCNO> 10532 </DOCNO>
Self-generated magnetic flux in YBa$_2$Cu$_3$O$_{7-x}$ grain boundaries


  Grain boundaries in YBa$_2$Cu$_3$O$_{7-x}$ superconducting films are
considered as Josephson junctions with a critical current density $j_c(x)$
alternating along the junction. A self-generated magnetic flux is treated both
analytically and numerically for an almost periodic distribution of $j_c(x)$.
We obtained a magnetic flux-pattern similar to the one which was recently
observed experimentally.

</DOC>
<DOC>
<DOCNO> 8489 </DOCNO>
Correlation Effects in Multi-Band Hubbard Model and Anomalous Properties


  The two-band Hubbard model with the density of states obtained from the band
calculation is applied for FeSi, which is suggested to be a Kondo insulator or
a correlated band insulator. Using this model, the correlation effects on FeSi
are investigated in terms of the self-consistent second-order perturbation
theory combined with the local approximation. The calculated optical
conductivity spectrum reproduces the experiments by Damascelli et al.
semiquantitatively and the specific heat explains the anomalous contribution at
about 250 K observed in FeSi. Inclusion of the spin fluctuation and the
extension to the case of strong correlation are also discussed.

</DOC>
<DOC>
<DOCNO> 12297 </DOCNO>
Entanglement of a Double Dot with a Quantum Point Contact


  Entanglement between particle and detector is known to be inherent in the
measurement process. Gurvitz recently analyzed the coupling of an electron in a
double dot (DD) to a quantum point contact (QPC) detector. In this paper we
examine the dynamics of entanglement that result between the DD and QPC. The
rate of entanglement is optimized as a function of coupling when the electron
is initially in one of the dots. It decreases asymptotically towards zero with
increased coupling. The opposite behavior is observed when the DD is initially
in a superposition: the rate of entanglement increases unboundedly as the
coupling is increased. The possibility that there are conditions for which
measurement occurs versus entanglement is considered.

</DOC>
<DOC>
<DOCNO> 121193 </DOCNO>
The Arecibo OH Megamaser Survey and the Galaxy Merger Rate


  We present the current results of a survey for OH megamasers (OHMs) underway
at the Arecibo Observatory. The survey is 2/3 complete and has produced a high
OHM detection rate (1 in 6) from a redshift-selected sample of IRAS galaxies.
The survey will relate the OHM luminosity function to the galaxy merger rate,
allowing subsequent blind OHM surveys to measure the galaxy merger rate as a
function of cosmic time. The survey has also made the first detection of strong
variability in OHMs. Variability will provide a powerful tool for understanding
the small-scale physical settings and mechanisms of OHMs.

</DOC>
<DOC>
<DOCNO> 7926 </DOCNO>
Magnetic and Thermodynamic Properties of the Collective Paramagnet-Spin


  In a recent letter [Phys. Rev. Lett. {\bf 82}, 1012 (1999)] it was found that
the Tb$^{3+}$ magnetic moments in the Tb$_2$Ti$_2$O$_7$ pyrochlore lattice of
corner-sharing tetrahedra remain in a {\it collective paramagnetic} state down
to 70mK. In this paper we present results from d.c. magnetic susceptibility,
specific heat data, inelastic neutron scattering measurements, and crystal
field calculations that strongly suggest that (1) the Tb$^{3+}$ ions in
Tb$_2$Ti$_2$O$_7$ possess a moment of approximatively 5$\mu_{\rm B}$, and (2)
the ground state $g-$tensor is extremely anisotropic below a temperature of
$O(10^0)$K, with Ising-like Tb$^{3+}$ magnetic moments confined to point along
a local cubic $<111>$ diagonal (e.g. towards the middle of the tetrahedron).
Such a very large easy-axis Ising like anisotropy along a $<111>$ direction
dramatically reduces the frustration otherwise present in a Heisenberg
pyrochlore antiferromagnet. The results presented herein underpin the
conceptual difficulty in understanding the microscopic mechanism(s) responsible
for Tb$_2$Ti$_2$O$_7$ failing to develop long-range order at a temperature of
the order of the paramagnetic Curie-Weiss temperature $\theta_{\rm CW} \approx
-10^1$K. We suggest that dipolar interactions and extra perturbative exchange
coupling(s)beyond nearest-neighbors may be responsible for the lack of ordering
of Tb$_2$Ti$_2$O$_7$.

</DOC>
<DOC>
<DOCNO> 118346 </DOCNO>
Hidden source of high-energy neutrinos in collapsing galactic nucleus


  We propose the model of a short-lived very powerful source of high energy
neutrinos. It is formed as a result of the dynamical evolution of a galactic
nucleus prior to its collapse into a massive black hole and formation of
high-luminosity AGN. This stage can be referred to as ``pre-AGN''. A dense
central stellar cluster in the galactic nucleus on the late stage of evolution
consists of compact stars (neutron stars and stellar mass black holes). This
cluster is sunk deep into massive gas envelope produced by destructive
collisions of a primary stellar population. Frequent collisions of neutron
stars in a central stellar cluster are accompanied by the generation of
ultrarelativistic fireballs and shock waves. These repeating fireballs result
in a formation of the expanding rarefied cavity inside the envelope. The
charged particles are effectively accelerated in the cavity and, due to
pp-collisions in the gas envelope, they produce high energy neutrinos. All high
energy particles, except neutrinos, are absorbed in the thick envelope.
Duration of this pre-AGN phase is about 10 yr, the number of the sources can be
\~ 10 per cosmological horizon. High energy neutrino signal can be detected by
underground neutrino telescope with effective area ~1 km^2.

</DOC>
<DOC>
<DOCNO> 116673 </DOCNO>
Radiometric force in dusty plasmas


  A radiofrequency glow discharge plasma, which is polluted with a certain
number of dusty grains, is studied. In addition to various dusty plasma
phenomena, several specific colloidal effects should be considered. We focus on
radiometric forces, which are caused by inhomogeneous temperature distribution.
Aside from thermophoresis, the role of temperature distribution in dusty
plasmas is an open question. It is shown that inhomogeneous heating of the
grain by ion flows results in a new photophoresis like force, which is specific
for dusty discharges. This radiometric force can be observable under conditions
of recent microgravity experiments.

</DOC>
<DOC>
<DOCNO> 83078 </DOCNO>
On the accuracy and running time of GSAT


  Randomized algorithms for deciding satisfiability were shown to be effective
in solving problems with thousands of variables. However, these algorithms are
not complete. That is, they provide no guarantee that a satisfying assignment,
if one exists, will be found. Thus, when studying randomized algorithms, there
are two important characteristics that need to be considered: the running time
and, even more importantly, the accuracy --- a measure of likelihood that a
satisfying assignment will be found, provided one exists. In fact, we argue
that without a reference to the accuracy, the notion of the running time for
randomized algorithms is not well-defined. In this paper, we introduce a formal
notion of accuracy. We use it to define a concept of the running time. We use
both notions to study the random walk strategy GSAT algorithm. We investigate
the dependence of accuracy on properties of input formulas such as
clause-to-variable ratio and the number of satisfying assignments. We
demonstrate that the running time of GSAT grows exponentially in the number of
variables of the input formula for randomly generated 3-CNF formulas and for
the formulas encoding 3- and 4-colorability of graphs.

</DOC>
<DOC>
<DOCNO> 84595 </DOCNO>
Evaporation of near-extremal Reissner-Nordstrom black holes


  The formation of near-extremal Reissner-Nordstrom black holes in the S-wave
approximation can be described, near the event horizon, by an effective
solvable model. The corresponding one-loop quantum theory remains solvable and
allows to follow analytically the evaporation process which is shown to require
an infinite amount of time.

</DOC>
<DOC>
<DOCNO> 85658 </DOCNO>
"True Transformations Relativity" and Electrodynamics


  Different approaches to special relativity (SR) are discussed. The first
approach is an invariant approach in which physical quantities in the
four-dimensional spacetime are represented by true tensors or equivalently by
coordinate-based geometric quantities comprising both components and a basis.
This approach we call the ''true transformations (TT) relativity.'' It is
compared with the usual covariant approach, which mainly deals with the basis
components of true tensors. The third approach is the usual noncovariant
approach to SR in which some quantities are not tensor quantities, but rather
quantities from ''3+1'' space and time, e.g., the synchronously determined
spatial length. This formulation is called the ''apparent transformations (AT)\
relativity.'' The spacetime length is considered in the ''TT relativity'' and
spatial and temporal distances in the ''AT relativity.'' It is also found that
the usual transformations of the three-vectors of the electric and magnetic
fields $\QTR{bf}{E}$ and $\QTR{bf}{B}$ are the AT. The Maxwell equations with
$F^{ab}$ are written in terms of the 4-vectors of the electric $E^{a}$ and
magnetic $B^{a}$ fields. The covariant Majorana electromagnetic field 4-vector
$\Psi ^{a}$ is constructed by means of 4-vectors $E^{a}$ and $B^{a}$ and the
covariant Majorana formulation of electrodynamics is presented. A Dirac like
relativistic wave equation for the free photon is obtained.

</DOC>
<DOC>
<DOCNO> 7837 </DOCNO>
The effects of nuclear spins on the quantum relaxation of the


  The strong influence of nuclear spins on resonant quantum tunneling in the
molecular cluster Fe_8 is demonstrated for the first time by comparing the
relaxation rate of the standard Fe_8 sample with two isotopic modified samples:
(i) 56_Fe is replaced by 57_Fe, and (ii) a fraction of 1_H is replaced by 2_H.
By using a recently developed "hole digging" method, we measured an intrinsic
broadening which is driven by the hyperfine fields. Our measurements are in
good agreement with numerical hyperfine calculations. For T > 1.5 K, the
influence of nuclear spins on the relaxation rate is less important, suggesting
that spin-phonon coupling dominates the relaxation rate at higher temperature.

</DOC>
<DOC>
<DOCNO> 119033 </DOCNO>
The cosmological lens equation in a universe with non zero cosmological


  We derive and solve exactly the Dyer-Roeder equation in a
Friedman-Robertson-Walker cosmological model with non zero cosmological
constant. To take into account non homogeneous distribution of matter we use
the phenomenological clumpiness parameter. We propose also a general form of an
approximate solution which is simple enough to be useful in practical
applications and sufficiently accurate in the interesting range of redshifts.

</DOC>
<DOC>
<DOCNO> 70329 </DOCNO>
In-medium pi-pi Correlation Induced by Partial Restoration of Chiral


  We show that both the linear and the non-linear chiral models give an
enhancement of the pi-pi cross section near the 2pi threshold in the
scalar-iso-scalar (I=J=0) channel in nuclear matter. The reduction of the
chiral condensate, i.e., the partial chiral restoration in nuclear matter, is
responsible for the enhancement in both cases. We extract an effective
4pi-nucleon vertex which is responsible for the enhancement but has not been
considered in the non-liear models for in-medium pi-pi interaction. Relation of
this vertex and a next-to-leading order terms in the heavy-baryon chiral
lagrangian, L_piN^(2), is also discussed.

</DOC>
<DOC>
<DOCNO> 9854 </DOCNO>
Hermitian extension of the four-dimensional Hooke's law


  It has been shown recently that the classical law of elasticity, expressed in
terms of the displacement three-vector and of the symmetric deformation
three-tensor, can be extended to the four dimensions of special and of general
relativity with a physically meaningful outcome. In fact, the resulting stress-
momentum-energy tensor can provide a unified account of both the elastic and
the inertial properties of uncharged matter. The extension of the displacement
vector to the four dimensions of spacetime allows a further possibility. If the
real displacement four-vector is complemented with an imaginary part, the
resulting complex ``displacement'' four-vector allows for a complex, Hermitian
generalisation of the four-dimensional Hooke's law. Let the complex, Hermitian
``stress-momentum-energy'' tensor density built in this way be subjected to the
usual conservation condition. It turns out that, while the real part of the
latter equation is able to account for the motion of electrically charged,
elastic matter, the imaginary part of the same equation can describe the
evolution of the electromagnetic field and of its sources. The Hermitian
extension of Hooke's law is performed by availing of the postulate of
``transposition invariance'', introduced in 1945 by A. Einstein for finding the
nonsymmetric generalisation of his theory of gravitation of 1915.

</DOC>
<DOC>
<DOCNO> 85484 </DOCNO>
Characteristic numerical relativity applied to hydrodynamic studies of


  We present tests and results of a new axisymmetric, fully general
relativistic code capable of solving the coupled Einstein-matter system for a
perfect fluid matter field. Our implementation is based on the Bondi metric, by
which the spacetime is foliated with a family of outgoing light cones. We use
high-resolution shock-capturing schemes to solve the fluid equations. The code
can accurately maintain long-term stability of a spherically symmetric,
relativistic, polytropic equilibrium model of a neutron star. In axisymmetry,
we demonstrate global energy conservation of a perturbed neutron star in a
compactified spacetime, for which the total energy radiated away by
gravitational waves corresponds to a significant fraction of the Bondi mass.

</DOC>
<DOC>
<DOCNO> 85161 </DOCNO>
On the consistency of a repulsive gravity phase in the early Universe


  We exploit the possibility of existence of a repulsive gravity phase in the
evolution of the Universe. A toy model with a free scalar field minimally
coupled to gravity, but with the "wrong sign" for the energy and negative
curvature for the spatial section, is studied in detail. The background
solutions display a bouncing, non-singular Universe. The model is well-behaved
with respect to tensor perturbations. But, it exhibits growing models with
respect to scalar perturbations whose maximum occurs in the bouncing. Hence,
large inhomogeneties are produced. At least for this case, a repulsive phase
may destroy homogeneity, and in this sense it may be unstable. A newtonian
analogous model is worked out; it displays qualitatively the same behaviour.
The generality of this result is discussed. In particular, it is shown that the
addition of an attractive radiative fluid does not change essentially the
results. We discuss also a quantum version of the classical repulsive phase,
through the Wheeler-de Witt equation in mini-superspace, and we show that it
displays essentially the same scenario as the corresponding attractive phase.

</DOC>
<DOC>
<DOCNO> 72055 </DOCNO>
On Possibility of Decoherence in Correlated two Neutral Kaon Systems


  We point out that decoherence parameters in the correlated two neutral kaon
system breaks the transformation invariance of basis and their magnitude are
stringently limited by the experimentally measured magnitudes of CP violation
and of the strangeness non conserving $\Delta S = \pm 2$ transitions.

</DOC>
<DOC>
<DOCNO> 120113 </DOCNO>
ASCA Observations of the Jet Source XTE J1748-288


  XTE J1748-288 is a new X-ray transient with a one-sided radio jet. It was
observed with ASCA on 1998/09/06 and 1998/09/26, 100 days after the onset of
the radio-X-ray outburst. The spectra were fitted with an attenuated power-law
model, and the 2-6-keV flux was 4.6 * 10^{-11} erg s^{-1} cm^{-2} and 2.2 *
10^{-12} on 09/06 and 09/26, respectively. The light curve showed that the
steady exponential decay with an e-folding time of 14 days lasted over 100 days
and 4 orders of magnitude from the peak of the outburst. The celestial region
including the source had been observed with ASCA on 1993/10/01 and 1994/09/22,
years before the discovery. In those period, the flux was < 10^{-13} erg s^{-1}
cm^{-2}, below ASCA's detection limit. The jet blob colliding to the
environmental matter was supposedly not the X-ray source, although the emission
mechanism has not been determined. A possible detection of a K line from highly
ionized iron is discussed.

</DOC>
<DOC>
<DOCNO> 40672 </DOCNO>
Zooming-in on Instantons at HERA


  In view of the intriguing, preliminary search results for instanton-induced
events at HERA from the H1 collaboration, some important remaining theoretical
issues are discussed. Notably, the question is addressed, to which extent the
H1 analysis may be directly compared to our original predictions from
instanton-perturbation theory, since certain fiducial cuts are lacking in the
H1 data. Various theoretical uncertainties are evaluated and their impact on
the observed excess is discussed. An improved understanding of the experimental
findings along with an encouraging over-all agreement with our original
predictions seems to emerge.

</DOC>
<DOC>
<DOCNO> 10048 </DOCNO>
Unusual Dynamical Scaling in the Spatial Distribution of Persistent


  The distribution, n(k,t), of the interval sizes, k, between clusters of
persistent sites in the dynamical evolution of the one-dimensional q-state
Potts model is studied using a combination of numerical simulations, scaling
arguments, and exact analysis. It is shown to have the scaling form n(k,t) =
t^{-2z} f(k/t^z), with z= max(1/2,theta), where theta(q) is the persistence
exponent which characterizes the fraction of sites which have not changed their
state up to time t. When theta > 1/2, the scaling length, t^theta, for the
interval-size distribution is larger than the coarsening length scale, t^{1/2},
that characterizes spatial correlations of the Potts variables.

</DOC>
<DOC>
<DOCNO> 69451 </DOCNO>
Inhomogeneous nucleation in quark hadron phase transition


  The effect of subcritical hadron bubbles on a first-order quark-hadron phase
transition is studied. These subcritical hadron bubbles are created due to
thermal fluctuations, and can introduce a finite amount of phase mixing (quark
phase mixed with hadron phase) even at and above the critical temperature. For
reasonable choices of surface tension and correlation length, as obtained from
the lattice QCD calculations, we show that the amount of phase mixing at the
critical temperature remains below the percolation threshold. Thus, as the
system cools below the critical temperature, the transition proceeds through
the nucleation of critical-size hadron bubbles from a metastable quark-gluon
phase (QGP), within an inhomogeneous background populated by an equilibrium
distribution of subcritical hadron bubbles. The inhomogeneity of the medium
results in a substantial reduction of the nucleation barrier for critical
bubbles. Using the corrected nucleation barrier, we estimate the amount of
supercooling for different parameters controlling the phase transition, and
briefly discuss its implications to cosmology and heavy-ion collisions.

</DOC>
<DOC>
<DOCNO> 150956 </DOCNO>
Note on irreducible approach to reducible second-class constraints


  An irreducible canonical approach to reducible second-class constraints is
given. The procedure is illustrated on gauge-fixed two-forms.

</DOC>
<DOC>
<DOCNO> 8587 </DOCNO>
Ferromagnetism and Canted Spin Phase in AlAs/GaMnAs Single Quantum


  The magnetic order resulting from a confinement-adapted
Ruderman-Kittel-Kasuya-Yosida indirect exchange between magnetic moments in the
metallic phase of a AlAs/Ga(1-x)Mn(x)As quantum well is studied by Monte Carlo
simulation. This coupling mechanism involves magnetic moments and carriers
(holes), both coming from the same Mn(2+) ions. It leads to a paramagnetic, a
ferromagnetic, or a canted spin phase, depending on the carrier concentration,
and on the magnetic layer width. It is shown that high transition temperatures
may be obtained.

</DOC>
<DOC>
<DOCNO> 169615 </DOCNO>
Nonadditive conditional entropy and its significance for local realism


  Based on the form invariance of the structures given by Khinchin's axiomatic
foundations of information theory and the pseudoadditivity of the Tsallis
entropy indexed by q, the concept of conditional entropy is generalized to the
case of nonadditive (nonextensive) composite systems. The proposed nonadditive
conditional entropy is classically nonnegative but can be negative in the
quantum context, indicating its utility for characterizing quantum
entanglement. A criterion deduced from it for separability of density matrices
for validity of local realism is examined in detail by employing a bipartite
spin-1/2 system. It is found that the strongest criterion is obtained in the
limit q going to infinity.

</DOC>
<DOC>
<DOCNO> 80640 </DOCNO>
Data storage issues in lattice QCD calculations


  I describe some of the data management issues in lattice Quantum
Chromodynamics calculations. I focus on the experience of the UKQCD
collaboration. I describe an attempt to use a relational database to store part
of the data produced by a lattice QCD calculation.

</DOC>
<DOC>
<DOCNO> 169798 </DOCNO>
On the nature of continuous physical quantities in classical and quantum


  Within the traditional Hilbert space formalism of quantum mechanics, it is
not possible to describe a particle as possessing, simultaneously, a sharp
position value and a sharp momentum value. Is it possible, though, to describe
a particle as possessing just a sharp position value (or just a sharp momentum
value)? Some, such as Teller (Journal of Philosophy, 1979), have thought that
the answer to this question is No -- that the status of individual continuous
quantities is very different in quantum mechanics than in classical mechanics.
On the contrary, I shall show that the same subtle issues arise with respect to
continuous quantities in classical and quantum mechanics; and that it is, after
all, possible to describe a particle as possessing a sharp position value
without altering the standard formalism of quantum mechanics.

</DOC>
<DOC>
<DOCNO> 102385 </DOCNO>
A non-overdetermined inverse problem of finding the potential from the


  Let $D\subset \R^n$, $n\geq 3,$ be a bounded domain with a $C^{\infty}$
boundary $S$, $L=-\nabla^2+q(x)$ be a selfadjoint operator defined in
$H=L^2(D)$ by the Neumann boundary condition, $\theta(x,y,\lambda)$ be its
spectral function, $\theta(x,y,\lambda):=\ds\sum_{\lambda_j<\lambda}
\phi_j(x)\phi$ where $L\phi_j=\lambda_j\phi_j$, $\phi_{j N}|_S=0,$
$\|\phi_j\|_{L^2(D)}=1$, $j=1,2,...$. The potential $q(x)$ is a real-valued
function, $q\in C^\infty(D)$. It is proved that $q(x)$ is uniquely determined
by the data $\theta(s,s,\lambda) \forall s\in S$, $\forall \lambda\in \R_+$ if
all the eigenvalues of $L$ are simple.

</DOC>
<DOC>
<DOCNO> 150670 </DOCNO>
Functional relations in Stokes multipliers - Fun with $x^6 + \alpha x^2$


  We consider eigenvalue problems in quantum mechanics in one dimension.
Hamiltonians contain a class of double well potential terms, x^6 + \alpha x^2,
for example . The space coordinate is continued to a complex plane and the
connection problem of fundamental system of solutions is considered. A hidden
U_q(\hat{gl}(2|1)) structure arises in "fusion relations" of Stokes
multipliers. With this observation, we derive coupled nonlinear integral
equations which characterize the spectral properties of both \pm \alpha
potentials simultaneously. equations.

</DOC>
<DOC>
<DOCNO> 70913 </DOCNO>
Infrared Fixed Points and Fixed Lines for Couplings in the Chiral


  In the framework of the low energy chiral Lagrangian renormalization group
equations for the couplings are investigated up to order p^6 -- as well for
SU(2)xSU(2) as for SU(3)xSU(3) chiral symmetry. Infrared attractive fixed
points for ratios of O(p^4) couplings are found, which turn out to agree with
the values determined from experiment in a surprisingly large number of cases.
Infrared attractive fixed line solutions for O(p^6) couplings in terms of
O(p^4) couplings and among O(p^6) couplings are determined.

</DOC>
<DOC>
<DOCNO> 170002 </DOCNO>
Exploiting exciton-exciton interactions in semiconductor quantum dots


  We propose an all-optical implementation of quantum-information processing in
semiconductor quantum dots, where electron-hole excitations (excitons) serve as
the computational degrees of freedom (qubits). We show that the strong dot
confinement leads to an overall enhancement of Coulomb correlations and to a
strong renormalization of the excitonic states, which can be exploited for
performing conditional and unconditional qubit operations.

</DOC>
<DOC>
<DOCNO> 80579 </DOCNO>
Topological Charge of Lattice Abelian Gauge Theory


  Configuration space of abelian gauge theory on a periodic lattice becomes
topologically disconnected by excising exceptional gauge field configurations.
It is possible to define a U(1) bundle from the nonexceptional link variables
by a smooth interpolation of the transition functions. The lattice analogue of
Chern character obtained by a cohomological technique based on the
noncommutative differential calculus is shown to give a topological charge
related to the topological winding number of the U(1) bundle.

</DOC>
<DOC>
<DOCNO> 121668 </DOCNO>
Magnetic lensing of ultra high energy cosmic rays


  We discuss several effects due to lensing of ultra high energy cosmic rays by
the regular component of the galactic magnetic field. Large flux magnification
around caustics can be a significant source of clustering in the arrival
directions of UHECRs of comparable energy. We also discuss lensing effects in a
hypothetical galactic magnetic wind model recently proposed to explain the
extremely high energy cosmic rays so far observed as originating from a single
source (M87). This model implies large flux magnifications, which reduce the
power requirements on the source, and a significant asymmetry in the expected
flux between the north and south galactic hemispheres.

</DOC>
<DOC>
<DOCNO> 9274 </DOCNO>
Incoherent Charge Dynamics in Perovskite Manganese Oxides


  A minimal model is proposed for the perovskite manganese oxides showing the
strongly incoherent charge dynamics with a suppressed Drude weight in the
ferromagnetic and metallic phase near the insulator. We investigate a
generalized double-exchange model including three elements; the orbital
degeneracy of $e_g$ conduction bands, the Coulomb interaction and fluctuating
Jahn-Teller distortions. We demonstrate that Lancz$\ddot{\rm o}$s
diagonalization calculations combined with Monte Carlo sampling of the largely
fluctuating lattice distortions result in the optical conductivity which
quantitatively accounts for the experimental indications. It is found that all
the three elements are indispensable to understand the charge dynamics in these
compounds.

</DOC>
<DOC>
<DOCNO> 178434 </DOCNO>
The neutron star in the Relativistic Mean-Field Theory


  The nucleon effective mass, binding energy and neutron star configuration in
the Relativistic Mean-Field Theory (RMF) is considered. The calculation are
motivated by the construction of the equation of state for a neutron star in
the RMF. The equation of state for the parameters set TM1 is calculated using
the Feynman - Bogolubov variational method for temperature different from zero.
The structure of the neutron star is presented. The maximal stable
configuration are obtained for: M_max=1.91 M_Sun and R=12.84 km.

</DOC>
<DOC>
<DOCNO> 99268 </DOCNO>
Numerical trivial fibrations


  We develop an intersection theory for a singular hemitian line bundle with
positive curvature current on a smooth projective variety and irreducible
curves on the variety. And we prove the existence of a natural rational
fibration structure associated with the singular hermitian line bundle. Also
for any pseudoeffective line bundle on a smooth projective variety, we prove
the existence of a rational natural fibration structure associated with the
line bundle.
  We also characterize a numerically trivial singular hermitain line bundle on
a smooth projective variety.

</DOC>
<DOC>
<DOCNO> 69882 </DOCNO>
Vacuum Structure and the Axion Walls in Gluodynamics and QCD with Light


  Large N gluodynamics was shown to have a set of metastable vacua with the
gluonic domain walls interpolating between them. The walls may separate the
genuine vacuum from an excited one, or two excited vacua which are unstable at
finite N (here N is the number of colors). One may attempt to stabilize them by
switching on the axion field. We study how the light quarks and the axion
affect the structure of the domain walls. In pure gluodynamics (with the axion
field) the axion walls acquire a very hard gluonic core. Thus, we deal with a
wall "sandwich" which is stable at finite N. In the case of the minimal axion,
the wall "sandwich" is in fact a "2-pi" wall, i.e., the corresponding field
configuration interpolates between identical hadronic vacua. The same
properties hold in QCD with three light quarks and very large number of colors.
However, in the realistic case of three-color QCD the phase corresponding to
the axion field profile in the axion wall is screened by a dynamical phase
associated with the eta-prime, so that the gluon component of the wall is not
excited. We propose a toy Lagrangian which models these properties and allows
one to get exact solutions for the domain walls.

</DOC>
<DOC>
<DOCNO> 8810 </DOCNO>
Negative in-plane and out-of-plane magnetoresistivities in optimally


  Both the in-plane and out-of-plane magnetoresistivities have been measured in
the normal state of an optimally doped Bi2Sr2Ca0.8Y0.2Cu2O8+d single crystal
with a magnetic field applied parallel and perpendicular to the CuO2 planes.
  Whatever the magnetic field and the current directions are, a negative
magnetoresistivity is obtained over a wide range of temperature above the
critical temperature Tc. For the in-plane and out-of-plane measurements, the
non-dominant orbital contribution to magnetoresistivity suggests the
substantial role played by the spin degrees of freedom.

</DOC>
<DOC>
<DOCNO> 174579 </DOCNO>
High Energy Heavy Ion Collisions: The Physics of Super-dense Matter


  I review experimental results from ultrarelativistic heavy ion collisions.
Signals of new physics and observables reflecting the underlying collision
dynamics are presented, and the evidence for new physics discussed.
Measurements of higher energy collisions at RHIC are described, and I give some
of the very first results.

</DOC>
<DOC>
<DOCNO> 120371 </DOCNO>
UVES observations of QSO 0000-2620: Molecular hydrogen abundance in the


  We have discovered molecular hydrogen in a fourth quasar damped Ly-alpha
system (hereafter DLA). The UVES spectrograph on the 8.2m ESO Kueyen telescope
has allowed the detection of H2 in gas with low metallicity, Z/Z_solar ~=
10^{-2}, and high neutral hydrogen column density, N(HI) ~= 2.6*10^{21}
cm^{-2}, at redshift z_abs = 3.3901 toward QSO 0000-2620. The measured H2
fractional abundance of f(H2) ~= 4*10^{-8} is lower than a typical value for
Galactic interstellar clouds of high N(HI) column density by a factor of
(2-3)*10^6. Since H2 molecules are formed efficiently on dust grains, it
implies that the dust condensation in this DLA is negligible, and hence the
abundances derived from metal absorption lines are the actual ones. The
obtained f(H2) value leads to an estimate of the dust number density of < n_d
>_DLA ~= 10^{-3}*< n_d >_ISM, which is consistent with the dust-to-gas ratio k
<= 1.6 10^{-3} derived independently from the [Cr/Zn] and [Fe/Zn] ratios.

</DOC>
<DOC>
<DOCNO> 9709 </DOCNO>
Weak localization correction to the FS interface resistance


  The classical resistance of a contact between a ferromagnet (F) and a
superconductor (S) acquires an additional contact term as compared to the
contact between a ferromagnet and a normal metal. The necessity to match
spin-polarized current in a ferromagnet to spin-less current in the
superconductor results in the accumulation of non-equilibrium polarization near
the F/S interface. In the present work, we show that the weak localization
correction to the classical diffusion coefficient, $\delta D$, is dependent on
the degree of polarization, with majority spins more likely to be reflected
from the interface than minority spins. Taking into account the change in the
spin polarized particle distribution in the F wire arising from $\delta D$, we
calculate the weak localization correction to the F/S contact resistance.

</DOC>
<DOC>
<DOCNO> 70892 </DOCNO>
Neutrino-pair emission due to electron-phonon scattering in a neutron


  The process of $\nu \bar{\nu}$ radiation due to interaction of electrons with
phonons in the crust of a cooling neutron star is studied with the consistent
account of an electromagnetic coupling between electrons in the medium. The
wavelength of radiated neutrinos and antineutrinos is typically much larger
than the electron Debye screening distance in the medium, and therefore plasma
polarization substantially modifies the effective weak current of the electron.
Is shown, that under above conditions plasma polarization screens totally a
vector weak interaction of the electron with a neutrino field. As a result, the
$\nu \bar{\nu}$ emissivity is less in approximately 2.23 times than previously
estimated.

</DOC>
<DOC>
<DOCNO> 40324 </DOCNO>
Search for the Decay K+ -> pi+ pi0 nu nubar


  The first search for the decay K^+ -> pi^+ pi^0 nu nubar has been performed
with the E787 detector at BNL. Based on zero events observed in the kinematical
search region defined by 90 MeV/c < P_{pi^+} < 188 MeV/c and 135 MeV < E_{pi^0}
< 180 MeV, an upper limit B(K^+ -> pi^+ pi^0 nu nubar) < 4.3 x 10^{-5} at 90%
confidence level is established.

</DOC>
<DOC>
<DOCNO> 117622 </DOCNO>
Weak lensing observations of the "dark" cluster MG2016+112


  We investigate the possible existence of a high-redshift (z=1) cluster of
galaxies associated with the QSO lens system MG2016+112. From an ultra-deep R-
and less deep V- and I-band Keck images and a K-band mosaic from UKIRT, we
detect ten galaxies with colors consistent with the lensing galaxy within
225h^{-1} kpc of the z=1.01 lensing galaxy. This represents an overdensity of
more than ten times the number density of galaxies with similar colors in the
rest of the image. We also find a group of seven much fainter objects closely
packed in a group only 27h^{-1} kpc north-west of the lensing galaxy. We
perform a weak lensing analysis on faint galaxies in the R-band image and
detect a mass peak of a size similar to the mass inferred from X-ray
observations of the field, but located 64" northwest of the lensing galaxy.
  From the weak lensing data we rule out a similar sized mass peak centered on
the lensing galaxy at the 2 sigma level.

</DOC>
<DOC>
<DOCNO> 151202 </DOCNO>
Zero-point energies and the multiplicative anomaly


  For the case of a relativistic scalar field at finite temperature with a
chemical potential, we calculate an exact expression for the one-loop effective
action using the full fourth order determinant and zeta-function
regularisation. We find that it agrees with the exact expression for the
factored operator and thus there appears to be no mulitplicative anomaly. The
appearance of the anomaly for the fourth order operator in the high temperature
limit is explained and we show that the multiplicative anomaly can be
calculated as the difference between two zeta-regularised zero-point energies.
This difference is a result of using a charge operator in the Hamiltonian which
has not been normal ordered.

</DOC>
<DOC>
<DOCNO> 119254 </DOCNO>
Is the Lambda CDM Model Consistent with Observations of Large-Scale


  The claim that large-scale structure data independently prefers the Lambda
Cold Dark Matter model is a myth. However, an updated compilation of
large-scale structure observations cannot rule out Lambda CDM at 95%
confidence. We explore the possibility of improving the model by adding Hot
Dark Matter but the fit becomes worse; this allows us to set limits on the
neutrino mass.

</DOC>
<DOC>
<DOCNO> 13285 </DOCNO>
Quantum Computation with Ballistic Electrons


  We describe a solid state implementation of a quantum computer using
ballistic single electrons as flying qubits in 1D nanowires. We show how to
implement all the steps required for universal quantum computation: preparation
of the initial state, measurement of the final state and a universal set of
quantum gates. An important advantage of this model is the fact that we do not
need ultrafast optoelectronics for gate operations. We use cold programming (or
pre-programming), i.e., the gates are set before launching the electrons; all
programming can be done using static electric fields only.

</DOC>
<DOC>
<DOCNO> 72020 </DOCNO>
From the Bethe-Salpeter equation to non-relativistic approaches with


  It is known that binding energies calculated from the Bethe-Salpeter equation
in ladder approximation can be reasonably well accounted for by an
energy-dependent interaction, at least for the lowest states. It is also known
that none of these approaches gives results close to what is obtained by using
the same interaction in the so-called instantaneous approximation, which is
often employed in non-relativistic calculations. However, a recently proposed
effective interaction was shown to account for the main features of both the
Bethe-Salpeter equation and the energy-dependent approach. In the present work,
a detailed comparison of these different methods for calculating binding
energies of a two-particle system is made. Some improvement, previously
incorporated for the zero-mass boson case in the derivation of the effective
interaction, is also employed for massive bosons. The constituent particles are
taken to be distinguishable and spinless. Different masses of the exchanged
boson (including a zero mass) as well as states with different angular momenta
are considered and the contribution of the crossed two-boson exchange diagram
is discussed. With this respect, the role played by the charge of the exchanged
boson is emphasized. It is shown that the main difference between the
Bethe-Salpeter results and the instantaneous approximation ones are not due to
relativity as often conjectured.

</DOC>
<DOC>
<DOCNO> 170298 </DOCNO>
Algebraic measures of entanglement


  We study the rank of a general tensor $u$ in a tensor product $H_1\ot...\ot
H_k$. The rank of $u$ is the minimal number $p$ of pure states $v_1,...,v_p$
such that $u$ is a linear combination of the $v_j$'s. This rank is an algebraic
measure of the degree of entanglement of $u$. Motivated by quantum computation,
we completely describe the rank of an arbitrary tensor in $(\C^2)^{\ot 3}$ and
give normal forms for tensor states up to local unitary transformations. We
also obtain partial results for $(\C^2)^{\ot 4}$; in particular, we show that
the maximal rank of a tensor in $(\C^2)^{\ot 4}$ is equal to 4.

</DOC>
<DOC>
<DOCNO> 99447 </DOCNO>
Hierarchy Structure of Graphs and Weighted Condensations


  By natural way the hierarchy structure is introduced on directed graphs with
weighted adjacencies. Embedded system of algebras of subsets of the set of
vertices of such digraph and it's consolidations, which vertices are the
elementary sets of corresponding algebra, are constructed. Weights of arcs of
consolidated graphs are determined.

</DOC>
<DOC>
<DOCNO> 14119 </DOCNO>
Thermodynamics of Bose-Einstein condensation of relativistic gas


  We show that the free relativistic wave equation which describes the particle
without or with rest mass has more than one part of energy spectrum. One part
of energy spectrum is beginning with rest energy and it is not limited by
above. This part of spectrum is called by us as normal. Another part of energy
spectrum is beginning with the zero energy . This part of spectrum is called by
us as anomalous since the zero energy corresponds to the infinite group
velocity.The presence of the zero in the energy spectrum permits to consider
the Bose-Einstein condensation. We show that the heat capasity has the finite
discontinuity at the condensation temperature. The last means that we have the
phase transition at the condensation point.

</DOC>
<DOC>
<DOCNO> 71945 </DOCNO>
A frequentist analysis of solar neutrino data


  We present a Monte Carlo analysis in terms of neutrino oscillations of the
total rates measured in solar neutrino experiments in the framework of
frequentist statistics. We show that the goodness of fit and the confidence
level of the allowed regions in the space of the neutrino oscillation
parameters are significantly overestimated in the standard method. We also
present a calculation of exact allowed regions with correct frequentist
coverage. We show that the exact VO, LMA and LOW regions are much larger than
the standard ones and merge together giving an allowed band at large mixing
angles for all Delta m^2 > 10^{-10} eV^2.

</DOC>
<DOC>
<DOCNO> 116449 </DOCNO>
Classical Radiation Processes in the Weizsacker-Williams Approximation


  The main features of radiation by relativistic electrons are well
approximated in the Weizsacker-Williams method of virtual quanta. This method
is best known for its application to radiation during elementary particle
collisions, but is equally useful in describing "classical" radiation emitted
during the interaction of a single relativistic electron with an extended
system, such as synchrotron radiation, undulator radiation, transition
radiation and Cerenkov radiation.

</DOC>
<DOC>
<DOCNO> 9851 </DOCNO>
Identifying the pairing symmetry in the Sr2RuO4 superconductor


  We have analyzed heat capacity and thermal conductivity measurements of
Sr2RuO4 in the normal and superconducting state and come to the conclusion that
an order parameter with nodal lines on the Fermi surface is required to account
for the observed low-temperature behavior. A gapped order parameter is
inconsistent with the reported thermodynamic and transport data. Guided by a
strongly peaked dynamical susceptibility along the diagonals of the Brillouin
zone in neutron scattering data, we suggest a spin-fluctuation mechanism that
would favor the pairing state with the gap maxima along the zone diagonals
(such as for a d_{xy} gap). The most plausible candidates are an odd parity,
spin-triplet, f-wave pairing state, or an even parity, spin-singlet, d-wave
state. Based on our analysis of possible pairing functions we propose
measurements of the ultrasound attenuation and thermal conductivity in the
magnetic field to further constrain the list of possible pairing states.

</DOC>
<DOC>
<DOCNO> 120471 </DOCNO>
HNCO in massive galactic dense cores


  We surveyed 81 dense molecular cores associated with regions of massive star
formation and Sgr A in the 5_{05}-4_{04} and 10_{010}-9_{09} lines of HNCO.
Line emission was detected towards 57 objects. Selected subsamples were also
observed in other HNCO lines covering a frequency range from 22 to 461 GHz.
HNCO lines from the K_{-1} = 2,3 ladders were detected in several sources.
Towards Orion-KL, K_{-1} = 5 transitions with upper state energies E_u/k ~ 1100
and 1300 K could be observed. Five HNCO cores were mapped. The sources remain
spatially unresolved at 220 and 461 GHz with beam sizes of 24" and 18",
respectively. Typical HNCO abundances relative to H_2 as derived from a
population diagram analysis are ~ 10^{-9}. The rotational temperatures reach ~
500 K. The gas densities in regions of HNCO $K_{-1}=0$ emission should be n >
10^6 cm^{-3} and in regions of K_{-1}>0 emission about an order of magnitude
higher even for radiative excitation. HNCO abundances are found to be enhanced
in high-velocity gas. HNCO integrated line intensities correlate well with
those of thermal SiO emission. This indicates a spatial coexistence of the two
species and may hint at a common production mechanism, presumably based on
shock chemistry.

</DOC>
<DOC>
<DOCNO> 123002 </DOCNO>
HST/STIS observations of the HeII Gunn-Peterson effect towards HE


  We present an HST STIS spectrum of the HeII Gunn-Peterson effect towards
HE2347-4342. Compared to the previous HST GHRS data obtained by Reimers et al.
(1997), the STIS spectrum has a much improved resolution. The 2-D detector also
allows us to better characterize the sky and dark background. We confirm the
presence of two spectral ranges of much reduced opacity, the opacity gaps, and
provide improved lower limits on the HeII G-P opacity in the high opacity
regions. We use the STIS spectrum together with a Keck--HIRES spectrum covering
the corresponding HI Lya forest to calculate a 1-D map of the softness S of the
ionization radiation along the line of sight towards HE 2347-4342, where S is
the ratio of the HI to HeII photoionization rates. We find that S is generally
large but presents important variations, from S ~ 30 in the opacity gaps to a 1
sigma lower limit of 2300 at z~2.86, in a region which shows an extremely low
HI opacity over a 6.5 A range. We note that a large S naturally accounts for
most of the large SiIV to CIV ratios seen in other quasar absorption line
spectra. We present a simple model that reproduces the shape of the opacity
gaps in absence of large individual absorption lines. We extend the model
described in Heap et al. (2000) to account for the presence of sources close to
the line of sight of the background quasar. As an alternative to the delayed
reionization model suggested by Reimers et al. (1997), we propose that the
large softness observed at z~2.86 is due to the presence of bright soft sources
close to the line of sight, i.e. for which the ratio between the number of HI
to HeII ionizing photons reaching the IGM is large. We discuss these two models
and suggest ways to discriminate between them.

</DOC>
<DOC>
<DOCNO> 70332 </DOCNO>
Pathways to Rare Baryonic B Decays


  We point out new ways to search for charmless baryonic B decays: baryon pair
production in association with $\eta^\prime$ is very likely as large as or even
a bit larger than two body $K\pi/\pi\pi$ modes. We extend our argument, in
weaker form, to $B\to \gamma + X_s$ and $\ell\nu +X$. Although calculations are
not reliable, estimates give branching ratios of order $10^{-5}$--$10^{-6}$,
where confidence is gained from recent experimental finding that $B \to D^{*} p
\bar n$, $D^{*} p \bar p \pi$ are not far below $D^*\pi$ and $D^*\rho$ rates.
Observation of charmless baryon modes would help clarify the dynamics of weak
decays to baryonic final states, while the self-analyzing prowess of the
$\Lambda$-baryon can be helpful in CP- and T-violation studies.

</DOC>
<DOC>
<DOCNO> 150877 </DOCNO>
Consistent Kaluza-Klein Sphere Reductions


  We study the circumstances under which a Kaluza-Klein reduction on an
n-sphere, with a massless truncation that includes all the Yang-Mills fields of
SO(n+1), can be consistent at the full non-linear level. We take as the
starting point a theory comprising a p-form field strength and (possibly) a
dilaton, coupled to gravity in the higher dimension D. We show that aside from
the previously-studied cases with (D,p)=(11,4) and (10,5) (associated with the
S^4 and S^7 reductions of D=11 supergravity, and the S^5 reduction of type IIB
supergravity), the only other possibilities that allow consistent reductions
are for p=2, reduced on S^2, and for p=3, reduced on S^3 or S^{D-3}. We
construct the fully non-linear Kaluza-Klein Ansatze in all these cases. In
particular, we obtain D=3, N=8, SO(8) and D=7, N=2, SO(4) gauged supergravities
from S^7 and S^3 reductions of N=1 supergravity in D=10.

</DOC>
<DOC>
<DOCNO> 100849 </DOCNO>
Generating Functional in CFT on Riemann Surfaces II: Homological Aspects


  We revisit and generalize our previous algebraic construction of the chiral
effective action for Conformal Field Theory on higher genus Riemann surfaces.
We show that the action functional can be obtained by evaluating a certain
Deligne cohomology class over the fundamental class of the underlying
topological surface. This Deligne class is constructed by applying a descent
procedure with respect to a \v{C}ech resolution of any covering map of a
Riemann surface. Detailed calculations are presented in the two cases of an
ordinary \v{C}ech cover, and of the universal covering map, which was used in
our previous approach. We also establish a dictionary that allows to use the
same formalism for different covering morphisms. The Deligne cohomology class
we obtain depends on a point in the Earle-Eells fibration over the
Teichm\"uller space, and on a smooth coboundary for the Schwarzian cocycle
associated to the base-point Riemann surface. From it, we obtain a variational
characterization of Hubbard's universal family of projective structures,
showing that the locus of critical points for the chiral action under fiberwise
variation along the Earle-Eells fibration is naturally identified with the
universal projective structure.

</DOC>
<DOC>
<DOCNO> 120870 </DOCNO>
Interpretation of Extreme Scattering Events


  Extreme Scattering Events are sometimes manifest in the light-curves of
compact radio-quasars at frequencies of a few GHz. These events are not
understood. The model which appears to offer the best explanation requires a
new population of AU-sized, neutral gas clouds; these clouds would then make up
a large fraction of the Galaxy's dark matter. Independent of the question of
which theoretical model is correct, if we extrapolate the observed behaviour to
low radio-frequencies, we expect that the sky should be criss-crossed by a
network of narrow caustics, at frequencies below about 700 MHz. Consequently at
these frequencies sources should typically manifest additional, faint images
which are substantially delayed with respect to the primary image. Although
some examples of this type of behaviour are already known, it is expected that
these are just the tip of the iceberg, with strong selection biases having been
imposed by the instrumentation employed to date.

</DOC>
<DOC>
<DOCNO> 151834 </DOCNO>
Supersymmetric Gauge Anomaly with General Homotopic Paths


  We use the method of Banerjee, Banerjee and Mitra and minimal homotopy paths
to compute the consistent gauge anomaly for several superspace models of SSYM
coupled to matter. We review the derivation of the anomaly for N=1 in four
dimensions and then discuss the anomaly for two-dimensional models with (2,0)
supersymmetry.

</DOC>
<DOC>
<DOCNO> 117102 </DOCNO>
Nuclear spin conversion in formaldehyde


  Theoretical model of the nuclear spin conversion in formaldehyde (H2CO) has
been developed. The conversion is governed by the intramolecular spin-rotation
mixing of molecular ortho and para states. The rate of conversion has been
found equal 1.4*10^{-4}~1/s*Torr. Temperature dependence of the spin conversion
has been predicted to be weak in the wide temperature range T=200-900 K.

</DOC>
<DOC>
<DOCNO> 12745 </DOCNO>
On Financial Markets Trading


  Starting from the observation of the real trading activity, we propose a
model of a stockmarket simulating all the typical phases taking place in a
stock exchange. We show that there is no need of several classes of agents once
one has introduced realistic constraints in order to confine money, time, gain
and loss within an appropriate range. The main ingredients are local and global
coupling, randomness, Zipf distribution of resources and price formation when
inserting an order. The simulation starts with the initial public offer and
comprises the broadcasting of news/advertisements and the building of the book,
where all the selling and buying orders are stored. The model is able to
reproduce fat tails and clustered volatility, the two most significant
characteristics of a real stockmarket, being driven by very intuitive
parameters.

</DOC>
<DOC>
<DOCNO> 8341 </DOCNO>
Multiscale Finite-Difference-Diffusion-Monte-Carlo Method for Simulating


  We present a novel hybrid computational method to simulate accurately
dendritic solidification in the low undercooling limit where the dendrite tip
radius is one or more orders of magnitude smaller than the characteristic
spatial scale of variation of the surrounding thermal or solutal diffusion
field. The first key feature of this method is an efficient multiscale
diffusion Monte-Carlo (DMC) algorithm which allows off-lattice random walkers
to take longer and concomitantly rarer steps with increasing distance away from
the solid-liquid interface. As a result, the computational cost of evolving the
large scale diffusion field becomes insignificant when compared to that of
calculating the interface evolution. The second key feature is that random
walks are only permitted outside of a thin liquid layer surrounding the
interface. Inside this layer and in the solid, the diffusion equation is solved
using a standard finite-difference algorithm that is interfaced with the DMC
algorithm using the local conservation law for the diffusing quantity. Here we
combine this algorithm with a previously developed phase-field formulation of
the interface dynamics and demonstrate that it can accurately simulate
three-dimensional dendritic growth in a previously unreachable range of low
undercoolings that is of direct experimental relevance.

</DOC>
<DOC>
<DOCNO> 12821 </DOCNO>
On the Kinetic Roughening in Polymer Film Growth by Vapor Deposition


  This is a Comment on a recent publication: Y.-P. Zhao et al., Phys. Rev.
Lett. 85, 3229 (2000). In the Letter, the authors report on an experimental
investigation of polymeric (p-xylene) thin film growth and propose a new
universality class not previously known. Here, we point out that the critical
exponents reported in the Letter are consistent with the critical exponents of
Das Sarma-Tamborenea growth model.

</DOC>
<DOC>
<DOCNO> 10020 </DOCNO>
Spin-Waves in itinerant ferromagnets


  We introduce a novel approach for the investigation of spin-wave excitations
in itinerant ferromagnets. Our theory is based on a variational treatment of
general multi-band Hubbard models which describe elements and compounds of
transition metals. The magnon dispersion is derived approximately as the energy
of a variational spin-wave state in the limit of large spatial dimensions. A
numerical evaluation of our results is feasible for general multi-band models.
As a first application we consider a model with two degenerate orbitals per
lattice site. From our results we can conclude that spin-wave excitations in
strong itinerant ferromagnets are very similar to those in ferromagnetic spin
systems.

</DOC>
<DOC>
<DOCNO> 151035 </DOCNO>
A note on the infinite-dimensional symmetries of classical hamiltonian


  We show that any Hamiltonian system with one degree of freedom is invariant
under a $w_\infty$ algebra of symmetries.

</DOC>
<DOC>
<DOCNO> 122279 </DOCNO>
Large-Scale Structure and Dark Matter Problem


  I review the observational data most relevant for large scale structure.
These data determine the system of cosmological parameters: the Hubble
parameter, densities of various populations of the Universe, parameters
characterizing the power spectrum of matter, including the biasing parameter of
galaxies relative to matter. Recent data suggest that the overall matter/energy
density is approximately equal to the critical density, and most (0.6 - 0.7) of
the density is in the form of cosmological term or ``dark (vacuum) energy''.
The density of the matter is 0.3 - 0.4 (including hot and cold dark matter and
luminous matter), the upper limit of the density of the hot dark matter is
0.05, all in units of the critical cosmological density.

</DOC>
<DOC>
<DOCNO> 116823 </DOCNO>
New Tasks and New Codes for RFQ Beam Simulation


  Proton linear accelerator is the base Accelerator Driven Power System (ADS).
Such ADS are dedicated to various purposes: weapon plutonium conversion,
"energy amplifier", transmutation of radionuclear wastes etc. Solution of these
tasks requires proton beams with energy 1 GeV and average current up to 30 mA.
At the moment there are no problems of fundamental nature in such linac
construction. The main problems have economic and technical aspects. Problems
of CW linac will be demonstrated on the base beam dynamics requirements. New
code package LIDOS.RFQ.Designer makes possible to simulate beam dynamics in RF
fields of real vane shape (including gaps between RFQ section) as well as to
determine channel parameters tolerances for reliable operation

</DOC>
<DOC>
<DOCNO> 70084 </DOCNO>
From Crepes to Pancakes in the MV Model


  The McLerran-Venugopalan model provides a framework which allows one to
compute the gluon distribution function of a very large nucleus from the
equations of QCD, provided that the longitudinal momentum fraction, xF, is
sufficiently small. The source of color charge for this computation may be
thought of as a crepe moving along the z axis at the speed of light. We refine
the MV model by allowing for the presence of non-trivial longitudinal
correlations between the color charges that comprise the nucleons. We find that
a consistent treatment forces us to consider a pancake-like source which moves
at slightly less than the speed of light. Our calculation allows us to consider
larger values of xF than were allowed in the original MV model.

</DOC>
<DOC>
<DOCNO> 83355 </DOCNO>
Estimation of Stochastic Attribute-Value Grammars using an Informative


  We argue that some of the computational complexity associated with estimation
of stochastic attribute-value grammars can be reduced by training upon an
informative subset of the full training set. Results using the parsed Wall
Street Journal corpus show that in some circumstances, it is possible to obtain
better estimation results using an informative sample than when training upon
all the available material. Further experimentation demonstrates that with
unlexicalised models, a Gaussian Prior can reduce overfitting. However, when
models are lexicalised and contain overlapping features, overfitting does not
seem to be a problem, and a Gaussian Prior makes minimal difference to
performance. Our approach is applicable for situations when there are an
infeasibly large number of parses in the training set, or else for when
recovery of these parses from a packed representation is itself computationally
expensive.

</DOC>
<DOC>
<DOCNO> 120023 </DOCNO>
Sinks of Light Elements in Stars - Part II


  The fragile light elements lithium, beryllium, and boron are easily destroyed
in stellar interiors, and are thus superb probes of physical processes occuring
in the outer stellar layers. The light elements are also excellent tracers of
the chemical evolution of the Galaxy, and can test big bang nucleosynthesis
(BBN). These inter-related topics are reviewed with an emphasis on stellar
physics.
  In Part I (presented by CPD), an overview is given of the physical processes
which can modify the surface abundances of the light elements, with emphasis on
Population I dwarfs - convection; gravitational settling, thermal diffusion,
and radiative levitation; slow mixing induced by gravity waves or rotation. We
will discuss the increasingly large body of data which begin to enable us to
discern the relative importance of these mechanisms in Population I main
sequence stars.
  In Part II (presented by MHP), discussion is extended to the issue of whether
or not the halo Li plateau is depleted, and includes the following topics: Li
dispersion in field and globular cluster stars, Li production vs. destruction
in Li-rich halo stars, and constraints from 6Li. Also discussed are trends with
metal abundance and Teff and implications for chemical evolution and BBN.
  In Part III (presented by CC), evidence is reviewed that suggests that in
situ mixing occurs in evolved low mass Population I and Population II stars.
Theoretical mechanisms that can create such mixing are discussed, as well as
their implications in stellar yields.

</DOC>
<DOC>
<DOCNO> 122164 </DOCNO>
Rotation Curves of Spiral Galaxies


  Rotation curves of spiral galaxies are the major tool for determining the
distribution of mass in spiral galaxies. They provide fundamental information
for understanding the dynamics, evolution and formation of spiral galaxies. We
describe various methods to derive rotation curves, and review the results
obtained. We discuss the basic characteristics of observed rotation curves in
relation to various galaxy properties, such as Hubble type, structure,
activity, and environment.

</DOC>
<DOC>
<DOCNO> 8251 </DOCNO>
Nonlinear Effect of Transport Current on Response of Metals to


  The nonlinear interaction of DC current flowing in a thin metal film with an
external low-frequency AC electromagnetic field is studied theoretically. The
nonlinearity is related to the influence of the magnetic field of the DC
current and the magnetic field of the wave on the form of electron
trajectories. This magnetodynamic mechanism of nonlinearity is the most typical
for pure metals at low temperatures. We find that such interaction causes sharp
kinks in the temporal dependence of the AC electric field of the wave on
surface of the sample. The phenomenon of amplification of the electromagnetic
signal on the metal surface is predicted. We also calculate the nonlinear
surface impedance and show that it turns out to be imaginary-valued and its
modulus decreases drastically with the increase of the wave amplitude.

</DOC>
<DOC>
<DOCNO> 150812 </DOCNO>
On the `Irreducible' Freedman-Townsend Vertex


  An irreducible cohomological derivation of the Freedman-Townsend vertex in
four dimensions is given.

</DOC>
<DOC>
<DOCNO> 178565 </DOCNO>
Probing the effectiveness: chiral perturbation theory calculations of


  I provide a brief, and therefore necessarily biased, review of the
application of effective field theory to electromagnetic processes on the
deuteron. Electron-deuteron scattering is discussed for virtual photon momenta
up to 700 MeV, and photon-deuteron scattering is examined for incident photon
energies of order the pion mass.

</DOC>
<DOC>
<DOCNO> 119237 </DOCNO>
Inertial Instability of Accretion Disks with Relativistic Electrons


  We show that accretion disks with relativisticly hot electrons which are
coupled to cold ions is subject to inertial-type instability in which kinematic
drag between electrons and ions produces radial acceleration of electrons.

</DOC>
<DOC>
<DOCNO> 67763 </DOCNO>
Exotic Quarkonia from Lattice QCD


  We present non-perturbative results for the spectrum of heavy quarkonia.
Using an anisotropic formulation of Lattice QCD we achieved an unprecedented
control over statistical and systematic errors. We also study relativistic
corrections to the leading order predictions for heavy hybrids and conventional
bound states.

</DOC>
<DOC>
<DOCNO> 85180 </DOCNO>
Quantized Fields and Chronology Protection


  Several recent possible counterexamples to the Chronology Protection
Conjecture are critically examined. The ``adapted'' Rindler vacuum state
constructed by Li and Gott for a conformal scalar field in Misner space is
extended to nonconformally coupled and self-interacting scalar fields. For
these fields, the vacuum stress-energy always diverges on the chronology
horizons. The divergence of the vacuum stress-energy on Misner space chronology
horizons cannot be generally avoided by choosing a Rindler-type vacuum state.

</DOC>
<DOC>
<DOCNO> 80700 </DOCNO>
String Breaking as a Mixing Phenomenon in the SU(2) Higgs Model


  We study the potential of a static quark anti-quark pair in the confinement
``phase'' of the SU(2) Higgs model. Around separation r_b, the confining string
of the gauge field breaks by formation of a dynamical pair of light quarks. The
ground state and first excited state static potentials are determined by a
variational technique from a matrix correlation in which suitably smeared gauge
and Higgs fields enter. Our results at beta=2.4 clearly show string breaking
(r_b ~ 1.9r_0). The investigation of properly defined overlaps confirms the
interpretation of string breaking as a level crossing phenomenon between
string-type and meson-type states. We study the scaling properties of the
static potentials along a line of constant physics, varying the lattice spacing
by a factor of 2. Our results show compatibility with scaling within tiny
errors.

</DOC>
<DOC>
<DOCNO> 70535 </DOCNO>
Angular structure of diffraction dissociation at LHC


  We consider angular dependence of the diffractive dissociation processes at
high energies. It appeared that angular dependence of the diffractive
dissociation has no dip and bump structure at the LHC energies and would show a
smooth power-like decrease with $t$. The normalized differential cross-section
has a scaling behavior and depends on the ratio $-t/M^2$ only. These results
reflect general trends of unitarity limitations at high energies and are
realized within the chiral quark model with unitarization performed through the
generalized reaction matrix.

</DOC>
<DOC>
<DOCNO> 116733 </DOCNO>
Symmetries of Optical Phase Conjugation


  Various algebraic structures of degenerate four-wave mixing equations of
optical phase conjugation are analyzed. Two approaches (the spinorial and the
Lax-pair based), complementary to each other, are utilized for a systematic
derivation of conserved quantities. Symmetry groups of both the equations and
the conserved quantities are determined, and the corresponding generators are
written down explicitly. Relation between these two symmetry groups is found.
Conserved quantities enable the introduction of new methods for integration of
the equations in the cases when the coupling $\Gamma$ is either purely real or
purely imaginary. These methods allow for both geometries of the process,
namely the transmission and the reflection, to be treated on an equal basis.
One approach to introduction of Hamiltonian and Lagrangian structures for the
4WM systems is explored, and the obstacles in successful implementation of that
programe are identified. In case of real coupling these obstacles are
removable, and full Hamiltonian and Lagrangian formulations of the initial
system are possible.

</DOC>
<DOC>
<DOCNO> 11339 </DOCNO>
Surmounting Oscillating Barriers: Path-integral approach for Weak Noise


  We consider the thermally activated escape of an overdamped Brownian particle
over a potential barrier in the presence of periodic driving. A time-dependent
path-integral formalism is developed which allows us to derive asymptotically
exact weak-noise expressions for both the instantaneous and the time-averaged
escape rate. Our results comprise a conceptionally new, systematic treatment of
the rate prefactor multiplying the exponentially leading Arrhenius factor.
Moreover, an estimate for the deviations at finite noise-strengths is provided
and a supersymmetry-type property of the time averaged escape rate is verified.
For piecewise parabolic potentials, the rate-expression can be evaluated in
closed analytical form, while in more general cases, as exemplified by a cubic
potential, an action-integral remains to be minimized numerically. Our
comparison with very accurate numerical results demonstrates an excellent
agreement with the theoretical predictions over a wide range of driving
strengths and driving frequencies.

</DOC>
<DOC>
<DOCNO> 39691 </DOCNO>
Observation of D-pi Production Correlations in 500 GeV pi- - N


  We study the charge correlations between charm mesons produced in 500 GeV pi-
- N interactions and the charged pions produced closest to them in phase space.
With 110,000 fully reconstructed D mesons from experiment E791 at Fermilab, the
correlations are studied as functions of the Dpi - D mass difference and of
Feynman x. We observe significant correlations which appear to originate from a
combination of sources including fragmentation dynamics, resonant decays, and
charge of the beam.

</DOC>
<DOC>
<DOCNO> 170466 </DOCNO>
Model for the arrival-time distribution in fluorescence time-of-flight


  An operational arrival-time distribution is defined as the distribution of
detection times of the first photons emitted by two level atoms in resonance
with a perpendicular laser beam in a time of flight experiment. For ultracold
Cesium atoms the simulations are in excellent agreement with the theoretical
ideal time-of-arrival distribution of Kijowski.

</DOC>
<DOC>
<DOCNO> 178603 </DOCNO>
Algebraic Model for scattering of three-s-cluster systems. II.


  The resonance states embedded in the three-cluster continuum of 6He and 6Be
are obtained in the Algebraic Version of the Resonating Group Method. The model
accounts for a correct treatment of the Pauli principle. It also provides the
correct three-cluster continuum boundary conditions by using a Hyperspherical
Harmonics basis. The model reproduces the observed resonances well and achieves
good agreement with other models. A better understanding for the process of
formation and decay of the resonance states in six-nucleon systems is obtained.

</DOC>
<DOC>
<DOCNO> 121161 </DOCNO>
Infrared Observations of AR Ursae Majoris: Modeling the Ellipsoidal


  We have obtained time-series infrared photometry for the highly magnetic
cataclysmic variable AR UMa. Our J and K' band observations occurred during a
low state and they show a distinctive double-humped structure. Using detailed
models for the expected ellipsoidal variations in the infrared due to the
non-spherical secondary star, we find that the most likely value for the system
inclination is 70 degrees. We also model low state V band photometry and find
that its observed double-humped structure is not caused by ellipsoidal
variations, as they have been ascribed to, but are due to beamed cyclotron
radiation. We use this result to estimate the magnetic field strength of the
active southern accretion region (B <= 190 MG) and its magnetic longitude (330
degrees).

</DOC>
<DOC>
<DOCNO> 117223 </DOCNO>
A phase-locked frequency divide-by-3 optical parametric oscillator


  Accurate phase-locked 3:1 division of an optical frequency was achieved, by
using a continuous-wave (cw) doubly resonant optical parametric oscillator. A
fractional frequency stability of 2*10^(-17) of the division process has been
achieved for 100s integration time. The technique developed in this work can be
generalized to the accurate phase and frequency control of any cw optical
parametric oscillator.

</DOC>
<DOC>
<DOCNO> 11159 </DOCNO>
Superdiffusion in Decoupled Continuous Time Random Walks


  Continuous time random walk models with decoupled waiting time density are
studied. When the spatial one jump probability density belongs to the Levy
distribution type and the total time transition is exponential a generalized
superdiffusive regime is established. This is verified by showing that the
square width of the probability distribution (appropriately defined)grows as
$t^{2/\gamma}$ with $0<\gamma\leq2$ when $t\to \infty$. An important connection
of our results and those of Tsallis' nonextensive statistics is shown. The
normalized q-expectation value of $x^2$ calculated with the corresponding
probability distribution behaves exactly as $t^{2/\gamma}$ in the asymptotic
limit.

</DOC>
<DOC>
<DOCNO> 70170 </DOCNO>
On factorisation at small x


  We investigate factorisation at small x using a variety of analytical and
numerical techniques. Previous results on factorisation in collinear models are
generalised to the case of the full BFKL equation, and illustrated in the
example of a collinear model which includes higher twist terms. Unlike the
simplest collinear model, the BFKL equation leads to effective anomalous
dimensions containing higher-twist pieces which grow as a (non-perturbative)
power at small x. While these pieces dominate the effective splitting function
at very small x they do not lead to a break-down of factorisation insofar as
their effect on the predicted scaling violations remains strongly suppressed.

</DOC>
<DOC>
<DOCNO> 12841 </DOCNO>
Diabolical Points in Molecular Magnets with a Four-Fold Easy Axis


  We study the points of degeneracy (diabolical points) in magnetic molecules
such as Mn_{12}-acetate that have an easy axis of four-fold symmetry. This is
done for general magnetic field that need not be oriented along a high-symmetry
direction. We develop a perturbative technique that gives the diabolical points
as the roots of a small number of polynomials in the transverse component of
the magnetic field and the fourth order basal plane anisotropy. In terms of
these roots we obtain approximate analytic formulas that apply to any system
with total spin S \le 10. The analytic results are found to compare reasonably
well with exact numerical diagonalization for the case of Mn12. In addition,
the perturbation theory shows that the diabolical points may be indexed by the
magnetic quantum numbers of the levels involved, even at large transverse
fields. Certain points of degeneracy are found to be mergers (or near mergers)
of two or three diabolical points beacuse of the symmetry of the problem.

</DOC>
<DOC>
<DOCNO> 68073 </DOCNO>
Maximal Neutrino Mixing from a Minimal Flavor Symmetry


  We study a number of models, based on a non-Abelian discrete group, that
successfully reproduce the simple and predictive Yukawa textures usually
associated with U(2) theories of flavor. These models allow for solutions to
the solar and atmospheric neutrino problems that do not require altering
successful predictions for the charged fermions or introducing sterile
neutrinos. Although Yukawa matrices are hierarchical in the models we consider,
the mixing between second- and third-generation neutrinos is naturally large.
We first present a quantitative analysis of a minimal model proposed in earlier
work, consisting of a global fit to fermion masses and mixing angles, including
the most important renormalization group effects. We then propose two new
variant models: The first reproduces all important features of the SU(5)xU(2)
unified theory with neither SU(5) nor U(2). The second demonstrates that
discrete subgroups of SU(2) can be used in constructing viable supersymmetric
theories of flavor without scalar universality even though SU(2) by itself
cannot.

</DOC>
<DOC>
<DOCNO> 67697 </DOCNO>
Breakdown of the KLN Theorem for Charged Particles in Condensed Matter


  The Kinoshita-Lee-Nauenberg (KLN) theorem describes the fact that inclusive
electromagnetic and weak production processes in the vacuum do not contain
singularities in the ultra-relativistic limit of zero mass. When these
production processes occur in condensed matter, the KLN theorem fails. One
consequence of this failure is that precision lifetime determinations of
stopped muons will depend on the nature of the surrounding material.

</DOC>
<DOC>
<DOCNO> 70481 </DOCNO>
Light-Cone Quantization: Foundations and Applications


  These lecture notes review the foundations and some applications of
light-cone quantization. First I explain how to choose a time in special
relativity. Inclusion of Poincare invariance naturally leads to Dirac's forms
of relativistic dynamics. Among these, the front form, being the basis for
light-cone quantization, is my main focus. I explain a few of its peculiar
features such as boost and Galilei invariance or separation of relative and
center-of-mass motion. Combining light-cone dynamics and field quantization
results in light-cone quantum field theory. As the latter represents a
first-order system, quantization is somewhat nonstandard. I address this issue
using Schwinger's quantum action principle, the method of Faddeev and Jackiw,
and the functional Schroedinger picture. A finite-volume formulation,
discretized light-cone quantization, is analysed in detail. I point out some
problems with causality, which are absent in infinite volume. Finally, the
triviality of the light-cone vacuum is established. Coming to applications, I
introduce the notion of light-cone wave functions as the solutions of the
light-cone Schroedinger equation. I discuss some examples, among them
nonrelativistic Coulomb systems and model field theories in two dimensions.
Vacuum properties (like chiral condensates) are reconstructed from the particle
spectrum obtained by solving the light-cone Schroedinger equation. In a last
application, I make contact with phenomenology by calculating the pion wave
function within the Nambu and Jona-Lasinio model. I am thus able to predict a
number of observables like the pion charge and core radius, the r.m.s.
transverse momentum, the pion structure function and the pion distribution
amplitude. The latter turns out to be the asymptotic one.

</DOC>
<DOC>
<DOCNO> 84704 </DOCNO>
Possibility of Control of the Gravitational Mass by means of Extra-Low


  According to the weak form of Einstein's general relativity equivalence
principle, the gravitational and inertial masses are equivalent. However recent
calculations (gr-qc/9910036) have revealed that they are correlated by an
adimensional factor, which is equal to one in absence of radiation only. We
have built an experimental system to check this unexpected theoretical result.
It verifies the effects of the extra-low frequency (ELF) radiation on the
gravitational mass of a body. We show that there is a direct correlation
between the radiation absorbed by the body and its gravitational mass,
independently of the inertial mass. This has fundamental consequences to
Unified Field Theory and Quantum Cosmology.

</DOC>
<DOC>
<DOCNO> 150751 </DOCNO>
Brane worlds: the gravity of escaping matter


  In the framework of a five-dimensional model with one 3-brane and an infinite
extra dimension, we discuss a process in which matter escapes from the brane
and propagates into the bulk to arbitrarily large distances. An example is a
decay of a particle of mass $2m$ residing on the brane into two particles of
mass $m$ that leave the brane and accelerate away. We calculate, in the
linearized theory, the metric induced by these particles on the brane. This
metric does not obey the four-dimensional Einstein equations and corresponds to
a spherical gravity wave propagating along the four-dimensional future light
cone. The four-dimensional space-time left behind the spherical wave is flat,
so the gravitational field induced in the brane world by matter escaping from
the brane disappears in a causal way.

</DOC>
<DOC>
<DOCNO> 70165 </DOCNO>
Runing of Axial Coupling Constant


  We illustrate that both of massless pseudoscalar meson fields and
constitutent quark fields are dynamical field degrees of freedom in energy
region between chiral symmetry spontaneously broken scale and quark confinement
scale. This physical configuration yields a renormalization running axial
coupling constant $g_{_A}(\mu)$. The one-loop renormalization prediction
$g_{_A}(\mu=m_{_N})=0.75$ and $g_{_A}(\mu=m_\pi)=0.96$ agree with $\beta$ decay
of neutron and $\pi^0\to\gamma\gamma$ respectively. We also calculate
$\rho^\pm\to\gamma\pi$ and $\omega\to\gamma\pi$ decays up to the next to
leading order of $N_c^{-1}$ expansion and including all order effects of vector
meson momentum expansion. The results strongly support prediction of
renormalization running, $g_{_A}(\mu=m_\rho)=0.77$.

</DOC>
<DOC>
<DOCNO> 12864 </DOCNO>
Generalized Lorentzian Triangulations and the Calogero Hamiltonian


  We introduce and solve a generalized model of 1+1D Lorentzian triangulations
in which a certain subclass of outgrowths is allowed, the occurrence of these
being governed by a coupling constant \beta. Combining transfer matrix-, saddle
point- and path integral techniques we show that for \beta<1 it is possible to
take a continuum limit in which the model is described by a 1D quantum Calogero
Hamiltonian. The coupling constant \beta survives the continuum limit and
appears as a parameter of the Calogero potential.

</DOC>
<DOC>
<DOCNO> 102622 </DOCNO>
An application of the DR-duality theory for compact groups to


  In Rev. Math. Phys. 4 (1997) 785 we study Hilbert-C* systems {F,G} where the
fixed point algebra A has nontrivial center Z and where A'\cap F=Z is
satisfied. The corresponding category of all canonical endomorphisms of A
contains characteristic mutually isomorphic subcategories of the
Doplicher/Roberts-type which are connected with the choice of distinguished
G-invariant algebraic Hilbert spaces within the corresponding G-invariant
Hilbert Z-modules. We present in this paper the solution of the corresponding
inverse problem. More precisely, assuming that the given endomorphism category
T of a C*-algebra A with center Z contains a certain subcategory of the
DR-type, a Hilbert extension {F,G} of A is constructed such that T is
isomorphic to the category of all canonical endomorphisms of A w.r.t. {F,G} and
A'\cap F=Z. Furthermore, there is a natural equivalence relation between
admissible subcategories and it is shown that two admissible subcategories
yield A-module isomorphic Hilbert extensions iff they are equivalent. The
essential step of the solution is the application of the standard DR-theory to
the assigned subcategory.

</DOC>
<DOC>
<DOCNO> 69954 </DOCNO>
Analytical Result for Dimensionally Regularized Massless Master Double


  The dimensionally regularized massless double box Feynman diagram with powers
of propagators equal to one, one leg off the mass shell, i.e. with non-zero
q^2=p_1^2, and three legs on shell, p_i^2=0, i=2,3,4, is analytically
calculated for general values of q^2 and the Mandelstam variables s and t. An
explicit result is expressed through (generalized) polylogarithms, up to the
fourth order, dependent on rational combinations of q^2,s and t, and a
one-dimensional integral with a simple integrand consisting of logarithms and
dilogarithms.

</DOC>
<DOC>
<DOCNO> 100190 </DOCNO>
Quantization of Lie bialgebras, part VI: quantization of generalized


  This paper is a continuation of the series of papers "Quantization of Lie
bialgebras (QLB) I-V". We show that the image of a Kac-Moody Lie bialgebra with
the standard quasitriangular structure under the quantization functor defined
in QLB-I,II is isomorphic to the Drinfeld-Jimbo quantization of this Lie
bialgebra, with the standard quasitriangular structure. This implies that when
the quantization parameter is formal, then the category O for the quantized
Kac-Moody algebra is equivalent, as a braided tensor category, to the category
O over the corresponding classical Kac-Moody algebra, with the tensor category
structure defined by a Drinfeld associator. This equivalence is a
generalization of the functor constructed previously by G.Lusztig and the
second author.
  In particular, we answer positively a question of Drinfeld whether the
characters of irreducible highest weight modules for quantized Kac-Moody
algebras are the same as in the classical case.
  Moreover, our results are valid for the Lie algebra g(A) corresponding to any
symmetrizable matrix A (not necessarily with integer entries), which answers
another question of Drinfeld.
  We also prove the Drinfeld-Kohno theorem for the algebra g(A) (it was
previously proved by Varchenko using integral formulas for solutions of the KZ
equations).

</DOC>
<DOC>
<DOCNO> 69677 </DOCNO>
Right-handed Neutrinos in $\nu_{\mu} + e \to \nu_{\mu} + e$ Elastic


  In this paper a scenario admitting the participation of the exotic
right-handed scalar $S_{R}$ coupling in addition to the standard left-handed
$(V, A)_{L}$ couplings in the low energy neutrino-electron scattering is
considered. The main goal is to show how the presence of the right-handed
neutrinos in the $(\nu e)$ scattering changes the laboratory differential cross
section in relation to the Standard Model prediction. We consider the $(\nu e)$
process at the level of the four-fermion point interaction. Muon-neutrinos are
assumed to be massive and to be polarized Dirac fermions. In the laboratory
differential cross section the new interference term between the the standard
$V_{L}$ coupling of the left-handed neutrino and exotic $S_{R}$ coupling of the
right-handed neutrino appears which does not vanish in the limit of massless
neutrino. This new contribution, including the information about the transverse
neutrino polarization, generates the azimuthal assymetry in the angular
distribution of the recoil electrons. This regularity would be the proof of the
presence of R-handed neutrinos in the $\nu e$ scattering.

</DOC>
<DOC>
<DOCNO> 12521 </DOCNO>
Recent progress in the truncated Lanczos method : application to


  The truncated Lanczos method using a variational scheme based on Hilbert
space reduction as well as a local basis change is re-examined. The energy is
extrapolated as a power law function of the Hamiltonian variance. This
systematic extrapolation procedure is tested quantitatively on the two-leg t-J
ladder with two holes. For this purpose, we have carried out calculations of
the spin gap and of the pair dispersion up to size 2x15.

</DOC>
<DOC>
<DOCNO> 10841 </DOCNO>
On Page's examples challenging the entropy bound


  According to the entropy bound, the entropy of a complete physical system can
be universally bounded in terms of its circumscribing radius and total
gravitating energy. Page's three recent candidates for counterexamples to the
bound are here clarified and refuted by stressing that the energies of all
essential parts of the system must be included in the energy the bound speaks
about. Additionally, in response to an oft heard claim revived by Page, I give
a short argument showing why the entropy bound is obeyed at low temperatures by
a complete system. Finally, I remark that Page's renewed appeal to the
venerable ``many species'' argument against the entropy bound seems to be
inconsistent with quantum field theory.

</DOC>
<DOC>
<DOCNO> 99619 </DOCNO>
Equivalence of Examples of Sacksteder and Bourgain


  Finding examples of tangentially degenerate submanifolds (submanifolds with
degenerate Gauss mappings) in an Euclidean space $R^4$ that are noncylindrical
and without singularities is an important problem of differential geometry. The
first example of such a hypersurface was constructed by Sacksteder in 1960. In
1995 Wu published an example of a noncylindrical tangentially degenerate
algebraic hypersurface in $R^4$ whose Gauss mapping is of rank 2 and which is
also without singularities. This example was constructed (but not published) by
Bourgain.
  In this paper, the authors analyze Bourgain's example, prove that, as was the
case for the Sacksteder hypersurface, singular points of the Bourgain
hypersurface are located in the hyperplane at infinity of the space $R^4$, and
these two hypersurfaces are locally equivalent.

</DOC>
<DOC>
<DOCNO> 69280 </DOCNO>
Analytic coupling and Sudakov effects in exclusive processes: pion and


  We develop and discuss in technical detail an infrared-finite factorization
and optimized renormalization scheme for calculating exclusive processes, which
enables the inclusion of transverse degrees of freedom without entailing
suppression of calculated observables, like form factors. This is achieved by
employing an analytic, i.e., infrared stable, running strong coupling $\alpha
_{\rm s}(Q^{2})$ which removes the Landau singularity at $Q^{2}=\Lambda_{\rm
QCD}^{2}$ by a minimum power-behaved correction. The ensuing contributions to
the cusp anomalous dimension - related to the Sudakov form factor - and to the
quark anomalous dimension - which controls evolution - lead to an enhancement
at high $Q^{2}$ of the hard part of exclusive amplitudes, calculated in
perturbative QCD, while simultaneously improving its scaling behavior. The
phenomenological implications of this framework are analyzed by applying it to
the pion's electromagnetic form factor, including the NLO contribution to the
hard-scattering amplitude, and also to the pion-photon transition at LO. For
the pion wave function, an improved ansatz of the Brodsky-Huang-Lepage type is
employed, which includes an effective (constituent-like) quark mass, $m_{\rm
q}=0.33$ GeV. Predictions for both form factors are presented and compared to
the experimental data, applying Brodsky-Lepage-Mackenzie commensurate scale
setting. We find that the perturbative hart part prevails at momentum transfers
above about 20 GeV ${}^{2}$, while at lower $Q^{2}$-values the pion form factor
is dominated by Feynman-type contributions. The theoretical prediction for the
$\gamma ^{*}\gamma \to \pi ^{0}$ form factor indicates that the true pion
distribution amplitude may be somewhat broader than the asymptotic one.

</DOC>
<DOC>
<DOCNO> 151123 </DOCNO>
A Derivation of K-Theory from M-Theory


  We show how some aspects of the K-theory classification of RR fluxes follow
from a careful analysis of the phase of the M-theory action. This is a
shortened and simplified companion paper to ``E8 Gauge Theory, and a Derivation
of K-Theory from M-Theory.''

</DOC>
<DOC>
<DOCNO> 10010 </DOCNO>
Scaling properties of one-dimensional Anderson models in an electric


  We investigate the scaling properties of eigenstates of a one-dimensional
(1D) Anderson model in the presence of a constant electric field. The states
show a transition from exponential to factorial localization. For infinite
systems this transition can be described by a simple scaling law based on a
single parameter $\lambda_{\infty} = l_{\infty}/l_{\rm el}$, the ratio between
the Anderson localization length $l_{\infty}$ and the Stark localization
length~$l_{\rm el}$. For finite samples, however, the system size $N$ enters
the problem as a third parameter. In that case the global structure of
eigenstates is uniquely determined by two scaling parameters
$\lambda_N=l_\infty/N$ and $\lambda_\infty=l_\infty/l_{\rm el}$.

</DOC>
<DOC>
<DOCNO> 10707 </DOCNO>
Spin waves and electronic interactions in La2CuO4


  The magnetic excitations of the square-lattice spin-1/2 antiferromagnet and
high-Tc parent La2CuO4 are determined using high-resolution inelastic neutron
scattering. Sharp spin waves with absolute intensities in agreement with theory
including quantum corrections are found throughout the Brillouin zone. The
observed dispersion relation shows evidence for substantial interactions beyond
the nearest-neighbor Heisenberg term, which can be understood in terms of a
cyclic or ring exchange due to the strong hybridization path around the Cu4O4
square plaquettes.

</DOC>
<DOC>
<DOCNO> 67868 </DOCNO>
Light vector meson photoproduction at large t


  We have studied in perturbative QCD all independent helicity amplitudes
describing the photoproduction of light vector mesons at large $t$. We found a
new hard production mechanism which is related to the possibility for a real
photon to fluctuate into a massless $q\bar q$ pair in a chiral-odd spin
configuration. Each helicity amplitude is given as a sum of a usual chiral-even
contribution (when the helicities of quark and antiquark are antiparallel) and
this additional chiral-odd part (where the helicities of quark and antiquark
are parallel). The chiral-odd contribution is large, it leads to a dominance of
the non spin-flip amplitude in a very broad region of intermediately high
$|t|$. All amplitudes are expressed in terms of short distance asymptotics of
the light-cone wave functions of vector meson (photon). We demonstrate that for
each helicity amplitude there exists a soft non-factorizable contribution. We
give arguments that for dominant non spin-flip helicity amplitude the relative
contribution of the soft nonfactorizable interactions is numerically not large.

</DOC>
<DOC>
<DOCNO> 8831 </DOCNO>
Determination of the complex microwave photoconductance of a single


  A small quantum dot containing approximately 20 electrons is realized in a
two-dimensional electron system of an AlGaAs/GaAs heterostructure. Conventional
transport and microwave spectroscopy reveal the dot's electronic structure. By
applying a coherently coupled two-source technique, we are able to determine
the complex microwave induced tunnel current. The amplitude of this
photoconductance resolves photon-assisted tunneling (PAT) in the non-linear
regime through the ground state and an excited state as well. The out-of-phase
component (susceptance) allows to study charge relaxation within the quantum
dot on a time scale comparable to the microwave beat period.

</DOC>
<DOC>
<DOCNO> 9427 </DOCNO>
Answer to the comment of Chudnovsky: On the square-root time relaxation


  Answer to the comment of E. Chudnovsky concerning the following papers:
  (1) N.V. Prokof'ev, P.C.E. Stamp, Phys. Rev. Lett.80, 5794 (1998).
  (2) W. Wernsdorfer, T. Ohm, C. Sangregorio, R. Sessoli, D. Mailly, C.
Paulsen, Phys. Rev. Lett. 82, 3903 (1999).

</DOC>
<DOC>
<DOCNO> 72226 </DOCNO>
Tau Physics: Theoretical Perspective


  The leptonic decays of the tau lepton provide relevant tests on the structure
of the weak currents and the universality of their couplings to the gauge
bosons. The hadronic tau decay modes constitute an ideal tool for studying
low--energy effects of the strong interaction in very clean conditions.
Accurate determinations of the QCD coupling and the strange quark mass have
been obtained with tau decay data. New physics phenomena, such as a non-zero
tau neutrino mass or violations of conservation laws can also be searched for
with tau decays.

</DOC>
<DOC>
<DOCNO> 72189 </DOCNO>
A Brane World Perspective on the Cosmological Constant and the Hierarchy


  We elaborate on the recently proposed static brane world scenario, where the
effective 4-D cosmological constant is exponentially small when parallel
3-branes are far apart. We extend this result to a compactified model with two
positive tension branes. Besides an exponentially small effective 4-D
cosmological constant, this model incorporates a Randall-Sundrum-like solution
to the hierarchy problem. Furthermore, the exponential factors for the
hierarchy problem and the cosmological constant problem obey an inequality that
is satisfied in nature. This inequality implies that the cosmological constant
problem can be explained if the hierarchy problem is understood. The basic idea
generalizes to the multibrane world scenario. We discuss models with piecewise
adjustable bulk cosmological constants (to be determined by the 5-dimensional
Einstein equation), a key element of the scenario. We also discuss the global
structure of this scenario and clarify the physical properties of the particle
(Rindler) horizons that are present. Finally, we derive a 4-D effective theory
in which all observers on all branes not separated by particle horizons measure
the same Newton's constant and 4-D cosmological constant.

</DOC>
<DOC>
<DOCNO> 151258 </DOCNO>
String action with multiplet of $\Theta$-terms and the hidden Poincare


  We study string action with multiplet of $\Theta$-terms added, which turns
out to be closely related with the bosonic sector of D=11 superstring action
[3,4]. Alternatively, the model can be considered as describing class of
special solutions of the membrane. An appropriate set of variables is find, in
which the light-cone quantization turns out to be possible. It is shown that
anomaly terms in the algebra of the light-cone Poincare generators are absent
for the case D=27.

</DOC>
<DOC>
<DOCNO> 119634 </DOCNO>
Wide-field imaging at mid infrared wavelengths: reconstruction of


  Ground-based astronomical observations at thermal infrared wavelengths face
the problem of extracting the weak astronomical signal from the large and
rapidly variable background flux. The observing strategy most commonly used,
the so-called ``chopping and nodding'' differential technique, provides
reliable representations of the target uniquely in the case of compact sources
while extended and complex sources can be easily distorted by their negative
counterparts. A restoration method, designed to remove the negative values and
to provide reliable representations of extended sources has been proposed. We
show that the algorithm successfully removes the distortions due to the
negative counterparts and, in addition, provides noise reduction.

</DOC>
<DOC>
<DOCNO> 71686 </DOCNO>
Neutral top-pion and top-charm production in high energy $e^{+}e^{-}$


  We calculate the contributions of the neutral top-pion, predicted by
topcolor-assisted technicolor (TC2) theory, to top-charm production via the
processes $\gamma\gamma \longrightarrow\bar{t}c$ and $e^{+}e^{-}\longrightarrow
\gamma\gamma\longrightarrow \bar{t}c$ at the high energy linear $e^{+}e^{-}$
collider (LC) experiments. The cross section is of order $10^{-2}pb$ in most of
the parameter space of TC2 theory, which may be detected at the LC experiments.
So the process $e^{+}e^{-}\longrightarrow \bar{t}c$ can be used to detect the
signature of TC2 theory.

</DOC>
<DOC>
<DOCNO> 83444 </DOCNO>
Applying Machine Translation to Two-Stage Cross-Language Information


  Cross-language information retrieval (CLIR), where queries and documents are
in different languages, needs a translation of queries and/or documents, so as
to standardize both of them into a common representation. For this purpose, the
use of machine translation is an effective approach. However, computational
cost is prohibitive in translating large-scale document collections. To resolve
this problem, we propose a two-stage CLIR method. First, we translate a given
query into the document language, and retrieve a limited number of foreign
documents. Second, we machine translate only those documents into the user
language, and re-rank them based on the translation result. We also show the
effectiveness of our method by way of experiments using Japanese queries and
English technical documents.

</DOC>
<DOC>
<DOCNO> 119196 </DOCNO>
BeppoSAX observations of Mrk 509 and MCG+8-11-11


  BeppoSAX observations of the Seyfert galaxies Mrk 509 and MCG+8-11-11 are
presented. Earlier evidence of a soft excess in Mrk 509 is confirmed. This
excess is found to be better represented by a power law than by a black body:
with a photon slope of 2.5, its extrapolation matches the flux recorded in the
far UV. An ASCA observation, which appeared to exclude the presence of the
excess while showing instead evidence of a warm absorber, turns out to be
compatible with the coexistence of the excess seen with BeppoSAX and of the
warm absorber. The hard power law of Mrk 509 is seen for the first time to be
affected by a cut-off at high energies, with an e-folding energy of about 70
keV. In MCG+8-11-11 the cut-off is found at about 170 keV, consistent within
the combined errors with a previous estimate from a ASCA+OSSE/CGRO observation.
In both objects the reflection component is clearly detected. In Mrk 509 its
strength, together with that of the iron K line, indicates a solid angle Omega,
subtended by the reprocessing gas in the accretion disk, much less than 2pi,
but lacking a valid constraint on the inclination angle this evidence is not as
convincing as that found with BeppoSAX in IC 4329A. In MCG+8-11-11 the same
parameters are instead consistent with Omega=2pi, but the comparison with an
ASCA observation, when the flux level was about 2.5 times weaker, suggests that
a substantial fraction of the angle might be associated with gas farther out
than the accretion disk.

</DOC>
<DOC>
<DOCNO> 8485 </DOCNO>
Excitons and Polarons in Quantum Wells


  We study properties of polarons and excitons confined to a potential
generated in a planar semiconductor heterostructure of the
$Ga_{1-x}Al_{x}As/GaAs/Ga_{1-x}Al_{x}As$ type. In contrast with results of
other authors peaks are found for the exciton energy and the polaron effective
mass as functions of the potential width while the polaron energy reveals
rather monotonous behavior.

</DOC>
<DOC>
<DOCNO> 170107 </DOCNO>
Conceptual Inadequacy of the Shannon Information in Quantum Measurements


  In a classical measurement the Shannon information is a natural measure of
our ignorance about properties of a system. There, observation removes that
ignorance in revealing properties of the system which can be considered to
preexist prior to and independent of observation. Because of the completely
different root of a quantum measurement as compared to a classical measurement
conceptual difficulties arise when we try to define the information gain in a
quantum measurement using the notion of Shannon information. The reason is
that, in contrast to classical measurement, quantum measurement, with very few
exceptions, cannot be claimed to reveal a property of the individual quantum
system existing before the measurement is performed.

</DOC>
<DOC>
<DOCNO> 39626 </DOCNO>
Neutrino Oscillation Appearance Experiment using Nuclear Emulsion and


  This report describes an apparatus that could be used to measure both the
identity and charge of an outgoing lepton in a charged current neutrino
interaction. This capability in a massive detector would allow the most
comprehensive set of neutrino oscillation physics measurements. By measuring
the six observable transitions between initial and final state neutrinos, one
would be able to measure all elements of the neutrino mixing matrix, as well as
search for CP violation, and matter effects. If the measured matrix is not
unitary, then one would also have an unambiguous determination of sterile
neutrinos. Emulsion is considered as the tracking medium, and different
techniques are discussed for the application of a magnetic field.

</DOC>
<DOC>
<DOCNO> 68027 </DOCNO>
New approximate solutions of the Ginsparg-Wilson equation - tests in 2-d


  A new method for finding approximate solutions of the Ginsparg-Wilson
equation is tested in 2-d. The Dirac operator is first constructed and then
used in a dynamical simulation of the 2-flavor Schwinger model. We find a very
small mass of the pi-particle implying almost chirally symmetric fermions. The
generalization of our method to 4-d is straightforward.

</DOC>
<DOC>
<DOCNO> 83320 </DOCNO>
Mapping WordNets Using Structural Information


  We present a robust approach for linking already existing lexical/semantic
hierarchies. We used a constraint satisfaction algorithm (relaxation labeling)
to select --among a set of candidates-- the node in a target taxonomy that
bests matches each node in a source taxonomy. In particular, we use it to map
the nominal part of WordNet 1.5 onto WordNet 1.6, with a very high precision
and a very low remaining ambiguity.

</DOC>
<DOC>
<DOCNO> 122006 </DOCNO>
The Nature of the Radiative Hydrodynamic Instabilities in Radiatively


  Atmospheres having a significant radiative support are shown to be
intrinsically unstable at luminosities above a critical fraction Gamma_crit ~
0.5-0.85 of the Eddington limit, with the exact value depending on the boundary
conditions. Two different types of absolute radiation-hydrodynamic
instabilities of acoustic waves are found to take place even in the electron
scattering dominated limit. Both instabilities grow over dynamical time scales
and both operate on non radial modes. One is stationary and arises only after
the effects of the boundary conditions are taken into account, while the second
is a propagating wave and is insensitive to the boundary conditions. Although a
significant wind can be generated by these instabilities even below the
classical Eddington luminosity limit, quasi-stable configurations can exist
beyond the Eddington limit due to the generally reduced effective opacity.
  The study is done using a rigorous numerical linear analysis of a gray plane
parallel atmosphere under the Eddington approximation. We also present more
simplified analytical explanations.

</DOC>
<DOC>
<DOCNO> 121297 </DOCNO>
Properties and evolution of disk galaxies in a hierarchical formation


  We highlight some results from disk galaxy evolution models conceived within
a cosmological context. When disk mergers and strong disk-halo feedback are
omitted, several properties and correlations of disk galaxies seem to be
related to initial conditions given by the CDM model, for example, the
intensive galaxy properties, the disk Hubble sequence, and the Tully-Fisher
relation in the infrared bands.

</DOC>
<DOC>
<DOCNO> 71305 </DOCNO>
No Spontaneous CP Violation at Finite Temperature in the MSSM?


  In order to generate the baryon asymmetry of the Universe sufficiently strong
CP violation is needed. It was therefore proposed that at finite temperature
there might be spontaneous (transitional) CP violation within the bubble walls
at the electroweak phase transition in supersymmetric models. We investigate
this question in the MSSM.

</DOC>
<DOC>
<DOCNO> 69403 </DOCNO>
One-Loop Quantum Energy Densities of Domain Wall Field Configurations


  We discuss a simple procedure for computing one-loop quantum energies of any
static field configuration that depends non-trivially on only a single spatial
coordinate. We specifically focus on domain wall-type field configurations that
connect two distinct minima of the effective potential, and may or may not be
the solutions of classical field equations. We avoid the conventional summation
of zero-point energies, and instead exploit the relation between functional
determinants and solutions of associated differential equations. This approach
allows ultraviolet divergences to be easily isolated and extracted using any
convenient regularization scheme. Two examples are considered: two-dimensional
$\phi^4$ theory, and three-dimensional scalar electrodynamics with spontaneous
symmetry breaking at the one-loop level.

</DOC>
<DOC>
<DOCNO> 174587 </DOCNO>
Measurement of the Cross Section Asymmetry of the Reaction gp-->pi0p in


  The cross section asymmetry Sigma has been measured for the photoproduction
of pi0-mesons off protons, using polarized photons in the energy range Eg = 0.5
- 1.1 GeV. The CM angular coverage is Theta = 85 - 125 deg with energy and
angle steps of 25 MeV and 5 deg, respectively. The obtained Sigma data, which
cover the second and third resonance regions, are compared with existing
experimental data and recent phenomenological analyses. The influence of these
measurements on such analyses is also considered.

</DOC>
<DOC>
<DOCNO> 116787 </DOCNO>
Theory of periodic swarming of bacteria: application to Proteus


  The periodic swarming of bacteria is one of the simplest examples for pattern
formation produced by the self-organized collective behavior of a large number
of organisms. In the spectacular colonies of Proteus mirabilis (the most common
species exhibiting this type of growth) a series of concentric rings are
developed as the bacteria multiply and swarm following a scenario periodically
repeating itself. We have developed a theoretical description for this process
in order to get a deeper insight into some of the typical processes governing
the phenomena in systems of many interacting living units. All of our
theoretical results are in excellent quantitative agreement with the complete
set of available observations.

</DOC>
<DOC>
<DOCNO> 84544 </DOCNO>
Distributional Modes for Scalar Field Quantization


  We propose a mode-sum formalism for the quantization of the scalar field
based on distributional modes, which are naturally associated with a slight
modification of the standard plane-wave modes. We show that this formalism
leads to the standard Rindler temperature result, and that these modes can be
canonically defined on any Cauchy surface.

</DOC>
<DOC>
<DOCNO> 10418 </DOCNO>
Strong Confinement and Oscillations in Two-Component Bose-Einstein


  We present a new model of BEC dynamics based on strong confinement near the
ground state. The model predicts oscillations in a two-component condensate,
based on interference of non-spreading wave packets moving within a pair of
tilted nearly square potentials. The oscillations are similar to those recently
reported for a magnetically trapped $^{87}$Rb condensate, and the model's
predictions give good quantitative agreement with the experiments.

</DOC>
<DOC>
<DOCNO> 101339 </DOCNO>
Linear ill-posed problems and dynamical systems


  A linear equation Au=f (1) with a bounded, injective, but not boundedly
invertible linear operator in a Hilbert space H is studied. A new approach to
solving linear ill-posed problems is proposed. The approach consists of solving
a Cauchy problem for a linear equation in H, which is a dynamical system,
proving the existence and uniqueness of its global solution u(t), and
establishing that u(t) tends to a limit y, as t tends to infinity, and this
limit y solves equation (1). The case when f in (1) is given with some error is
also studied.

</DOC>
<DOC>
<DOCNO> 118767 </DOCNO>
Cosmological Surveys at Submillimetre Wavelengths


  One of the major goals of observational cosmology is to acquire empirical
data that has the diagnostic power to develop the theoretical modelling of the
high-redshift universe, ultimately leading to an accurate understanding of the
processes by which galaxies and clusters form and subsequently evolve. New
bolometer arrays operating on the world's largest submillimetre telescopes now
offer a unique view of the high-redshift universe through unbiassed surveys
with unprecedented sensitivity. For brevity, except when there is a need to be
more specific, the FIR to millimetre wavelength regime (100um < lambda <
6000um) will be referred to as the ``submillimetre'' (submm). One of the major
challenges in this field is to accurately quantify the star-formation history
of submm-selected galaxies, particularly those at redshifts > 1, and determine
their contribution to the submm extragalactic background. The field of
observational cosmology will be revolutionized during the course of the next 10
years due to the variety of powerful new ground-based, airborne and satellite
facilities, particularly those operating at FIR to millimetre wavelengths. This
review summarises the results from the recent blank-field submm surveys, and
describes the future observations that will provide accurate source-counts over
wider ranges of wavelength and flux-density, constrain the spectral energy
distributions of the submm-selected galaxies and accurately constrain the
redshift distribution and submm luminosity function by removing the current
ambiguities in the optical, IR and radio counterparts.

</DOC>
<DOC>
<DOCNO> 102070 </DOCNO>
On certain families of naturally graded Lie algebras


  In this work large families of naturally graded nilpotent Lie algebras in
arbitrary dimension and characteristic sequence (n,q,1), with n odd, satisfying
the centralizer property, are given. This condtion constitutes a
generalization, for a nilpotent Lie agebra, of the structural properties
charactrizing the Lie algebra $Q_{n}$. By considering certain cohomological
classes of the space $H^{2}(\frak{g},\mathbb{C})$, it is shown that, with few
exceptions, the isomorphism classses of these algebras are given by central
extensions of $Q_{n}$ by $\mathbb{C}^{p}$ which preserve the nilindex and the
natural graduation.

</DOC>
<DOC>
<DOCNO> 118778 </DOCNO>
Mass Loss On the Horizontal Branch: an Application to NGC6791


  The presence of a substantial number of hot stars in the extremely
metal-rich} open cluster NGC6791 has been a mystery. If these hot stars are in
their core helium burning phase, they are significantly bluer (hotter) than
predicted by canonical stellar evolution theory. No obvious explanation is
available yet. We consider the effects of mass loss during the evolution of
horizontal branch (HB) stars as their possible origin. We find that the
addition of mass loss causes HB stars to evolve to be hotter and fainter. Mass
loss has a more pronounced effect for less massive stars and thus naturally
widens the temperature (and color) distribution on the HB. If mass loss rates
are higher for more metal-rich stars, this phenomenon would be even more
pronounced in the metal-rich populations, such as NGC6791. We find that mass
loss on the HB may be a viable method of forming subdwarf B (sdB) stars both in
the field and in clusters, especially when the metallicity is high.

</DOC>
<DOC>
<DOCNO> 122010 </DOCNO>
BeppoSAX Observations of the Maser Sy2 Galaxy: ESO103-G35


  We have made BeppoSAX observations of the Seyfert 2/1.9 galaxy ESO103-G35,
which contains a nuclear maser source and is known to be heavily absorbed in
the X-rays. Analysis of the X-ray spectra observed by SAX in October 1996 and
1997 yields a spectral index 0.74+/-0.07, typical of Seyfert galaxies and
consistent with earlier observations of this source. The strong, soft X-ray
absorption has column density 1.79E(23)/cm^2, again consistent with earlier
results. The best fitting spectrum is that of a power law with a high energy
cutoff at 29+/-10 keV, a cold, marginally resolved Fe Kalpha line with EW 290
eV (1996) and a mildly ionized Fe K-edge at 7.37 keV. The Kalpha line and cold
absorption are consistent with origin in a accretion disk/torus through which
our line-of-sight passes at a radial distance of $\sim 50$ pc. The Fe K-edge is
mildly ionized suggesting the presence of ionized gas probably in the inner
accretion disk, close to the central source or in a separate warm absorber. The
data quality is too low to distinguish between these possibilities but the
edge-on geometry implied by the water maser emission favors the former.
Comparison with earlier observations of ESO103-G35 shows little/no change in
spectral parameters while the flux changes by factors of a few on timescales of
a few months. The 2--10 keV flux decreased by a factor of 2.7 between Oct 1996
and Oct 1997 with no detectable change in the count rate >20 keV suggesting a
constant or delayed response reflection component. The high energy cutoff is
lower than the typical 300keV values seen in Seyfert galaxies. A significant
subset of similar sources would affect current models of the AGN contribution
to the cosmic X-ray background which generally assume a high energy cutoff of
300 keV.

</DOC>
<DOC>
<DOCNO> 11258 </DOCNO>
Critical behavior and conservation in directed sandpiles


  We perform large-scale simulations of directed sandpile models with both
deterministic and stochastic toppling rules. Our results show the existence of
two distinct universality classes. We also provide numerical simulations of
directed models in the presence of bulk dissipation. The numerical results
indicate that the way in which dissipation is implemented is irrelevant for the
determination of the critical behavior. The analysis of the self-affine
properties of avalanches shows the existence of a subset of super-universal
exponents, whose value is independent of the universality class. This feature
is accounted for by means of a phenomenological description of the energy
balance condition in these models.

</DOC>
<DOC>
<DOCNO> 69334 </DOCNO>
Summing Sudakov logarithms in B -> X_s + gamma in effective field theory


  We construct an effective field theory valid for processes in which highly
energetic light-like particles interact with collinear and soft degrees of
freedom, using the decay B -> X_s + gamma near the endpoint of the photon
spectrum, x = 2 E_gamma / m_b -> 1, as an example. Below the scale mu=m_b both
soft and collinear degrees of freedom are included in the effective theory,
while below the scale mu=m_b sqrt{x-y}, where 1-y is the lightcone momentum
fraction of the b quark in the B meson, we match onto a theory of bilocal
operators. We show that at one loop large logarithms cancel in the matching
conditions, and that we recover the well known renormalization group equations
that sum leading Sudakov logarithms.

</DOC>
<DOC>
<DOCNO> 151228 </DOCNO>
D0-Branes As Confined Quarks


  The possibility of using the quantum mechanics of D0-branes for the
bound-states of quarks and QCD strings is investigated. Issues such as the
inter D0-branes potential, the whiteness of the D0-branes bound-states and the
large-N limit of D0-branes effective theory are studied. A possible role of the
non-commutativity of relative distances of D0-branes in a study of ordinary QCD
is discussed.

</DOC>
<DOC>
<DOCNO> 101633 </DOCNO>
Classification of polynomials from C^2 to C with one critical value


  We give the classification, up to homeomorphisms, of reduced complex
polynomials with 2 variables with one critical value.

</DOC>
<DOC>
<DOCNO> 12625 </DOCNO>
An asymmetric exclusion model with overtaking a numerical and simulation


  An asymmetric exclusion model on an open chain with random rates for hopping
particles, where overtaking is also possible, is studied numerically and by
computer simulation. The phase structure of the model and the density profiles
near the high and low density coexistence line are obtained. The effect of a
site impurity is also studied.

</DOC>
<DOC>
<DOCNO> 151161 </DOCNO>
On the relation between polynomial deformations of sl(2,R) and


  A general method based on the polynomial deformations of the Lie algebra
sl(2,R) is proposed in order to exhibit the quasi-exactly solvability of
specific Hamiltonians implied by quantum physical models. This method using the
finite-dimensional representations and differential realizations of such
deformations is illustrated on the sextic oscillator as well as on the second
harmonic generation.

</DOC>
<DOC>
<DOCNO> 70829 </DOCNO>
Quantum chaos and chiral symmetry at the QCD and QED phase transition


  We investigate the eigenvalue spectrum of the staggered Dirac matrix in SU(3)
gauge theory and in full QCD as well as in quenched U(1) theory. As a measure
of the fluctuation properties of the eigenvalues, we consider the
nearest-neighbor spacing distribution. We find that in all regions of their
phase diagrams, compact lattice gauge theories have bulk spectral correlations
given by random matrix theory, which is an indication for quantum chaos. In the
confinement phase, the low-lying Dirac spectrum of these quantum field theories
is well described by random matrix theory, exhibiting universal behavior.
Related results for gauge theories with minimal coupling are now discussed also
in the chirally symmetric phase.

</DOC>
<DOC>
<DOCNO> 85042 </DOCNO>
Coherent State Path Integrals without Resolutions of Unity


  From the very beginning, coherent state path integrals have always relied on
a coherent state resolution of unity for their construction. By choosing an
inadmissible fiducial vector, a set of ``coherent states'' spans the same space
but loses its resolution of unity, and for that reason has been called a set of
weak coherent states. Despite having no resolution of unity, it is nevertheless
shown how the propagator in such a basis may admit a phase-space path integral
representation in essentially the same form as if it had a resolution of unity.
Our examples are toy models of similar situations that arise in current studies
of quantum gravity.

</DOC>
<DOC>
<DOCNO> 9597 </DOCNO>
Novel type of orbital ordering: complex orbitals in doped Mott


  An orbital ordering, often observed in Mott insulators with orbital
degeneracy, is usually supposed to disappear with doping, e.g. in the
ferromagnetic metallic phase of manganites. We propose that the orbital
ordering of a novel type may exist in such situation: there may occur ferro
orbital ordering of complex orbitals (linear superposition of basic orbitals
d_x^2-y^2 and d_z^2 with complex coefficients). Despite the perfect orbital
ordering, such state still retains cubic symmetry and thus would not induce any
structural distortion. This novel state can resolve many problems in the
physics of CMR manganites and can also exist in other doped Mott insulators
with Jahn-Teller ions.

</DOC>
<DOC>
<DOCNO> 69196 </DOCNO>
Summary of the SUSY Working Group of the 1999 Les Houches Workshop


  The results obtained by the Working Group on Supersymmetry at the 1999 Les
Houches Workshop on Collider Physics are summarized. Separate chapters treat
"general" supersymmetry, R-parity violation, gauge mediated supersymmetry
breaking, and anomaly mediated supersymmetry breaking.

</DOC>
<DOC>
<DOCNO> 13504 </DOCNO>
Complex Dynamical Flow Phases and Pinning in Superconductors with


  We examine vortex pinning and dynamics in thin-film superconductors
interacting with square and rectangular pinning arrays for varied vortex
densities including densities significantly larger than the pinning density.
For both square and rectangular pinning arrays, the critical depinning force
shows maxima at only certain integer matching fields where the vortices can
form highly ordered arrays. For rectangular arrays the depinning force and
commensurability effects are anisotropic with a much lower depinning threshold
for vortex motion in the easy flow directions. We find evidence for a crossover
in pinning behavior in rectangular pinning arrays as the field is increased. We
also show analytically, and confirm with simulations, that for $B = 2B_{\phi}$
the strongest pinning can be achieved for rectangular pinning arrangements
rather than square for one direction of driving force. Under an applied driving
force we find a remarkable variety of distinct complex flow phases in both
square and rectangular arrays. These flow phases include stable sinusoidal and
intricate pinched patterns where vortices from different channels do not mix.
As a function of the driving force certain flow states become unstable and
transitions between different phases are observed which coincide with changes
in the net vortex velocities. In the rectangular arrays the types of flow
depend on the direction of drive. We also show that two general types of
plastic flow occur: stable flows, where vortices always flow along the same
paths, and unstable or chaotic flows.

</DOC>
<DOC>
<DOCNO> 121230 </DOCNO>
The Polarization Variability in the Optical Afterglow of GRB 990712


  In a recent paper, Rol and colleagues present evidence for a variable
polarization in the optical afterglow following the gamma-ray burst GRB 990712.
The variation is highly significant, but the position angle appears time
independent. Contrary to their conclusion, we point out that this can in fact
be explained with existing afterglow models, namely that of a laterally
expanding jet.

</DOC>
<DOC>
<DOCNO> 100654 </DOCNO>
Classification of Incidence Scrolls(I)


  The aim of this paper is to obtain a classification of scrolls of genus 0 and
1, which are defined by a one-dimensional family of lines meeting a certain set
of linear spaces in ${\bf P}^n$. These ruled surfaces will be called incidence
scrolls and such a set will be the base of the incidence scroll. Unless
otherwise stated, we assume that the base spaces are in general position.

</DOC>
<DOC>
<DOCNO> 68041 </DOCNO>
Production of transverse energy from minijets in next-to-leading order


  We compute in next-to-leading order (NLO) perturbative QCD the transverse
energy carried into the central rapidity unit of hadron or nuclear collisions
by the partons freed in the few-GeV subcollisions. The formulation is based on
a rapidity window and a measurement function of a new type. The behaviour of
the NLO results as a function of the minimum transverse momentum and as a
function of the scale choice is studied. The NLO results are found to be stable
relative to the leading-order ones even in the few-GeV domain.

</DOC>
<DOC>
<DOCNO> 152011 </DOCNO>
Gauge and Einstein Gravity from Non-Abelian Gauge Models on


  Following the formalism of enveloping algebras and star product calculus we
formulate and analyze a model of gauge gravity on noncommutative spaces and
examine the conditions of its equivalence to general relativity. The
corresponding Seiberg-Witten maps are established which allow the definition of
respective dynamics for a finite number of gravitational gauge field components
on noncommutative spaces.

</DOC>
<DOC>
<DOCNO> 70276 </DOCNO>
Correspondence of consistent and inconsistent spin-3/2 couplings via the


  The Rarita-Schwinger theory of free massive spin-3/2 field obeys the physical
degrees of freedom counting, and one can distinguish ``consistent'' couplings
which maintain this property and ``inconsistent'' couplings which destroy it.
We show how one can obtain consistent couplings from inconsistent ones by a
redefinition of the spin-3/2 field. The field redefinition gives rise to
additional ``contact terms'' which, via the equivalence theorem, can be
associated with the contribution of the extra lower-spin degrees of freedom
involved by the inconsistent coupling.

</DOC>
<DOC>
<DOCNO> 10916 </DOCNO>
The sn-pole approximation in the Composite Operator Method


  A well-established method to deal with highly correlated systems is based on
the expansion of the Green's function in terms of spectral moments. In the
context of the Composite Operator Method one approximation is proposed: a set
of n composite fields is assumed as fundamental basis and the dynamics is
considered up to the order s. The resulting Green's function has a sn-pole
structure. The truncation of the hierarchy of the equations of motion is made
at the s-th order and the first s-1 equations are treated exactly. A theorem,
which rules the conservation of the spectral moments, is presented. The
procedure is applied to the Hubbard model and a recurrence relation for the
calculation of its electronic spectral moments is derived.

</DOC>
<DOC>
<DOCNO> 116980 </DOCNO>
Inductive-Adder Kicker Modulator for Darht-2


  An all solid-state kicker modulator for the Dual-Axis Radiographic
Hydrodynamic Test facility (DARHT-2) has been designed and tested. This kicker
modulator uses multiple solid-state modules stacked in an inductive-adder
configuration where the energy is switched into each section of the adder by a
parallel array of MOSFETs. The modulator features very fast rise and fall
times, pulse width agility and a high pulse-repetition rate in burst mode. The
modulator can drive a 50* cable with voltages up to 20 kV and can be easily
configured for either positive or negative polarity. The presentation will
include test data collected from both the ETA II accelerator kicker and
resistive dummy loads.

</DOC>
<DOC>
<DOCNO> 71343 </DOCNO>
Quark-Hadron Duality, Factorization and Strong Phases in $B^0_d \to


  We consider the hadronic description of the $B^0_d\to \pi^+\pi^-$ decay, with
the aim to investigate the strong phases generated by the final state
interactions. The derivation of the dispersion relations using the
Lehmann-Symanzik-Zimmermann formalism and the Goldberger-Treiman method to
include inelastic effects in the spectral function are presented. We discuss
the problem of quark-hadron duality and estimate in the hadronic formalism the
corrections to the factorized amplitude in the heavy quark limit.

</DOC>
<DOC>
<DOCNO> 85394 </DOCNO>
Studies of the Schroedinger-Newton Equations in D Dimensions


  We investigate a $D$ dimensional generalization of the Schroedinger-Newton
equations, which purport to describe quantum state reduction as resulting from
gravitational effects. For a single particle, the system is a combination of
the Schroedinger and Poisson equations modified so that the probability density
of the wavefunction is the source of the potential in the Schroedinger
equation. For spherically symmetric wavefunctions, a discrete set of energy
eigenvalue solutions emerges for dimensions $D<6$, accumulating at D=6.
Invoking Heisenberg's uncertainty principle to assign timescales of collapse
correspoding to each energy eigenvalue, we find that these timescales may vary
by many orders of magnitude depending on dimension. For example, the time taken
for the wavefunction of a free neutron in a spherically symmetric state to
collapse is many orders of magnitude longer than the age of the universe,
whereas for one confined to a box of picometer-sized cross-sectional dimensions
the collapse time is about two weeks.

</DOC>
<DOC>
<DOCNO> 100919 </DOCNO>
On classification of Mori contractions: Elliptic curve case


  We study Mori's three-dimensional contractions $f\colon X\to Z$. It is proved
that on the ``good'' model $(\bar X,\bar S)$ the exceptional divisor has no
elliptic components of $Diff_{\bar S}$ with coefficients $\ge 6/7$.

</DOC>
<DOC>
<DOCNO> 150682 </DOCNO>
A quantum Peierls-Nabarro barrier


  Kink dynamics in spatially discrete nonlinear Klein-Gordon systems is
considered. For special choices of the substrate potential, such systems
support continuous translation orbits of static kinks with no (classical)
Peierls-Nabarro barrier. It is shown that these kinks experience, nevertheless,
a lattice-periodic confining potential, due to purely quantum effects anaolgous
to the Casimir effect of quantum field theory. The resulting ``quantum
Peierls-Nabarro potential'' may be calculated in the weak coupling
approximation by a simple and computationally cheap numerical algorithm, which
is applied, for purposes of illustration, to a certain two-parameter family of
substrates.

</DOC>
<DOC>
<DOCNO> 84700 </DOCNO>
p-Adic and Adelic Generalization of Quantum Cosmology


  p-Adic and adelic generalization of ordinary quantum cosmology is considered.
In [1], we have calculated p-adic wave functions for some minisuperspace
cosmological models according to the "no-boundary" Hartle-Hawking proposal. In
this article, applying p-adic and adelic quantum mechanics, we show existence
of the corresponding vacuum eigenstates. Adelic wave function contains some
information on discrete structure of space-time at the Planck scale.

</DOC>
<DOC>
<DOCNO> 69338 </DOCNO>
Recent results in Lorentz and CPT tests


  This talk summarizes some recent experimental constraints on Lorentz and CPT
violation.

</DOC>
<DOC>
<DOCNO> 151975 </DOCNO>
Localization of graviphoton and graviscalar on the brane


  The question of whether the Kaluza-Klein (KK) graviphoton $h_{5\mu}$ and
graviscalar $h_{55}$ are localized or not on the brane is one of the important
issues. In this letter, we address this problem in five dimensions. Here we
consider the massless (zero-mode) propagations without requiring the
Z$_2$-symmetry on $h_{5\mu}$. We obtain the graviton $h_{\mu\nu}$, graviphoton,
and graviscalar exchange amplitudes on shell. We find that the graviscalar has
a tachyonic mass. It turns out that $h_{5\mu}$ admits the localized zero-modes
on the brane while $h_{55}$ does not have a localized zero-mode. This is
contrasted to the fact that the bulk spin-0 field has a localized zero-mode on
the brane but the bulk spin-1 field does not have a localized solution in five
dimensions.

</DOC>
<DOC>
<DOCNO> 83381 </DOCNO>
Pattern Matching for sets of segments


  In this paper we present algorithms for a number of problems in geometric
pattern matching where the input consist of a collections of segments in the
plane. Our work consists of two main parts. In the first, we address problems
and measures that relate to collections of orthogonal line segments in the
plane. Such collections arise naturally from problems in mapping buildings and
robot exploration.
  We propose a new measure of segment similarity called a \emph{coverage
measure}, and present efficient algorithms for maximising this measure between
sets of axis-parallel segments under translations. Our algorithms run in time
$O(n^3\polylog n)$ in the general case, and run in time $O(n^2\polylog n)$ for
the case when all segments are horizontal. In addition, we show that when
restricted to translations that are only vertical, the Hausdorff distance
between two sets of horizontal segments can be computed in time roughly
$O(n^{3/2}{\sl polylog}n)$. These algorithms form significant improvements over
the general algorithm of Chew et al. that takes time $O(n^4 \log^2 n)$. In the
second part of this paper we address the problem of matching polygonal chains.
We study the well known \Frd, and present the first algorithm for computing the
\Frd under general translations. Our methods also yield algorithms for
computing a generalization of the \Fr distance, and we also present a simple
approximation algorithm for the \Frd that runs in time $O(n^2\polylog n)$.

</DOC>
<DOC>
<DOCNO> 71610 </DOCNO>
Hadronization of quark gluon plasma (and gluon jets) and the role of the


  Signatures of dominant and central production of glueballs (binary gluonic
mesons) in heavy ion and hadromic collisions are discussed. Search strategies
are proposed.

</DOC>
<DOC>
<DOCNO> 152584 </DOCNO>
Linear Models of Supersymmetric D-Branes


  We construct a class of supersymmetric boundary interactions in N=2 field
theories on the half-space, which depend on parameters that are not at all
renormalized or not renormalized in perturbation theory beyond one-loop. This
can be used to study D-branes wrapped on a certain class of Lagrangian
submanifolds as well as holomorphic cycles. The construction of holomorphic
D-branes is in close relationship with the background independent open string
field theory approach to brane/anti-brane systems. As an application, mirror
pairs of Lagrangian and holomorphic D-branes are identified. The mirror pairs
are studied by twisting to open topological field theories.

</DOC>
<DOC>
<DOCNO> 13031 </DOCNO>
Electronic phase diagram of La$_{1.875}$Ba$_{0.125-x}$Sr$_x$CuO$_4$


  We performed systematic measurements of magnetic susceptibility on single
crystals of La$_{1.875}$Ba$_{0.125-x}$Sr$_x$CuO$_4$. The dependence of the
superconducting transition temperature on Sr-concentration demonstrates a
step-like pattern upon doping at {\it x}$\sim$0.08 as the crystal structure
changes from low-temperature tetragonal (LTT) to low-temperature orthorhombic
(LTO) phase at low temperature. Upon cooling, an anomalous upturn in the
susceptibility was observed at the structural phase transition between the
LTT-LTO phases under the magnetic field parallel to {\it c}-axis.

</DOC>
<DOC>
<DOCNO> 11711 </DOCNO>
Phase behaviour of block copolymer melts with arbitrary architecture


  The Leibler theory [L. Leibler, Macromolecules, v.13, 1602 (1980)] for
microphase separation in AB block copolymer melts is generalized for systems
with arbitrary topology of molecules. A diagrammatic technique for calculation
of the monomeric correlation functions is developed. The free energies of
various mesophases are calculated within the second-harmonic approximation.
Model highly-branched tree-like structures are considered as an example and
their phase diagrams are obtained. The topology of molecules is found to
influence the spinodal temperature and asymmetry of the phase diagrams, but not
the types of phases and their order. We suggest that all model AB
block-copolymer systems will exhibit the typical phase behaviour.

</DOC>
<DOC>
<DOCNO> 121599 </DOCNO>
Power spectrum of the polarized diffuse Galactic radio emission


  We have analyzed the available polarization surveys of the Galactic emission
to estimate to what extent it may be a serious hindrance to forthcoming
experiments aimed at detecting the polarized component of Cosmic Microwave
Background (CMB) anisotropies. Regions were identified for which independent
data consistently indicate that depolarization must be small. The power
spectrum of the polarized emission, in terms of antenna temperature, was found
to be described by $C_{\ell}\simeq (1.2\pm 0.8)\cdot 10^{-9}\cdot (\ell /
450)^{-1.8\pm 0.3}\cdot (\nu/ 2.4{\rm GHz})^{-5.8}$ K$^{2}$, from arcminute to
degree scales. Data on larger angular scales ($\ell\le 100$) indicate a steeper
slope $\sim \ell^{-3}$. We conclude that polarized Galactic emission is
unlikely to be a serious limitation to CMB polarization measurements at the
highest frequencies of the MAP and {\sc Planck}/LFI instruments, at least for
$\ell\ge 50$ and standard cosmological models. The weak correlation between
polarization and total power and the low polarization degree of radio emission
close to the Galactic plane, found also in low-depolarization regions, is
interpreted as due to large contributions to the observed intensity from
unpolarized sources, primarily strong HII regions, concentrated on the Galactic
plane. Thus estimates of the power spectrum of total intensity at low Galactic
latitudes are not representative of the spatial distribution of Galactic
emission far from the plane. Both total power and polarized emissions show
highly significant deviations from a Gaussian distribution.

</DOC>
<DOC>
<DOCNO> 11929 </DOCNO>
Wigner molecules in quantum dots


  We perform unrestricted Hartree-Fock (HF) calculations for electrons in a
parabolic quantum dot at zero magnetic field. The crossover from Fermi liquid
to Wigner molecule behavior is studied for up to eight electrons and various
spin components $S_z$. We compare the results with numerically exact
path-integral Monte Carlo simulations and earlier HF studies. Even in the
strongly correlated regime the symmetry breaking HF solutions provide accurate
estimates for the energies and describe the one-particle densities
qualitatively. However, the HF approximation favors the formation of a Wigner
molecule and produces azimuthal modulations of the density for even numbers of
electrons in one spatial shell.

</DOC>
<DOC>
<DOCNO> 11158 </DOCNO>
External voltage sources and Tunneling in quantum wires


  We (re) consider in this paper the problem of tunneling through an impurity
in a quantum wire with arbitrary Luttinger interaction parameter. By combining
the integrable approach developed in the case of Quantum Hall edge states with
the introduction of radiative boundary conditions to describe the adiabatic
coupling to reservoirs, we are able to obtain the exact equilibrium and non
equilibrium current. One of the most striking features observed is the
appearance of negative differential conductances out of equilibrium in the
strongly interacting regime g <=.2. In spite of the various charging effects, a
remarkable form of duality is still observed.
  New results on the computation of transport properties in integrable impurity
problems are gathered in appendices. In particular, we prove that the TBA
results satisfy a remarkable relation, originally derived using the Keldysh
formalism, between the order T^2 correction to the current out of equilibrium
and the second derivative of this current at T=0 with respect to the voltage.

</DOC>
<DOC>
<DOCNO> 119471 </DOCNO>
Newtonian Limit of Induced Gravity


  We discuss the weak-field limit of induced gravity and show that results
directly depend on the coupling and self-interaction potential of the scalar
field. A static spherically symmetric exact solution is found and its conformal
properties are studied. As an application, it is shown that the light
deflection angle and the microlensing quantities can be parametrized by the
coupling of the theory.

</DOC>
<DOC>
<DOCNO> 122518 </DOCNO>
Warm Molecular Gas in Dwarf Starburst Galaxies: CO(3-2) Observations


  Eight dwarf starburst galaxies have been observed with the Caltech
Submillimeter Observatory (CSO) telescope in the CO J= 3 - 2 transition. The
galaxies observed are He 2-10, NGC 5253, NGC 1569, NGC 3077, Haro 2, Haro 3, II
Zw 40 and Mrk 86; all but the last two are detected. The central regions of He
2-10 and NGC 5253 were mapped and a CO(2-1) spectrum of NGC 5253 was obtained.
The error weighted mean CO(3-2)/CO(1-0) ratio of the detected galaxies is
0.60$\pm$0.06, which is virtually identical to what is found for starbursts in
the nuclei of nearby spirals, and suggests that the molecular gas is optically
thick, warm (T$_{k}>$20 K), and moderately dense ($n_{H_{2}}\sim 10^{3-4}
cm^{-3}$). The CO(3-2)/CO(1-0) ratio peaks at or close to the starburst in all
cases. CO emission does not appear to be optically thin in these dwarfs,
despite the low metallicity and intense radiation fields, which is probably
because in order for CO to exist in detectable amounts it must be
self-shielding and hence optically thick. Physical properties of the molecular
clouds in these dwarf starbursts appear to be essentially the same as nearby
spiral nuclei, with the possible exception that CO is more confined to the
cloud cores.

</DOC>
<DOC>
<DOCNO> 84961 </DOCNO>
Study of Coincidences between Resonant Gravitational Wave Detectors


  Coincidences are searched with the cryogenic resonant gravitational wave
detectors EXPLORER and NAUTILUS, during a period of about six months (2 June-14
December 1998) for a total measuring time of 94.5 days, with the purpose to
study new algorithms of analysis, based on the physical characteristics of the
detectors.

</DOC>
<DOC>
<DOCNO> 80637 </DOCNO>
Determinant of a new fermionic action on a lattice - (II)


  We investigate the fermion determinant of a new action on a
$(1+D)$-dimensional lattice for SU(2) gauge groups. This action possesses the
discrete chiral symmetry and provides $2^D$-component fermions. We also comment
on the numerical results on fermion determinants in the $(1+D)$-dimensional
SU(3) gauge fields.

</DOC>
<DOC>
<DOCNO> 170143 </DOCNO>
Variational Characterisations of Separability and Entanglement of


  In this paper we develop a mathematical framework for the characterisation of
separability and entanglement of formation (EoF) of general bipartite states.
These characterisations are of the variational kind, meaning that separability
and EoF are given in terms of a function which is to be minimized over the
manifold of unitary matrices. A major benefit of such a characterisation is
that it directly leads to a numerical procedure for calculating EoF. We present
an efficient minimisation algorithm and an apply it to the bound entangled 3X3
Horodecki states; we show that their EoF is very low and that their distance to
the set of separable states is also very low. Within the same variational
framework we rephrase the results by Wootters (W. Wootters, Phys. Rev. Lett.
80, 2245 (1998)) on EoF for 2X2 states and present progress in generalising
these results to higher dimensional systems.

</DOC>
<DOC>
<DOCNO> 11261 </DOCNO>
Anisotropic Disorder in High Mobility 2D Heterostructures and its


  Surface morphology of high mobility heterostructures is examined and
correlated with d.c. transport. {\it All} samples examined show evidence of
lines in the [1$\bar{1}$0] direction with roughness ranging from small
amplitude features to severe anisotropic ridges. Transport in these samples is
consistent with that in samples having artificially induced 1D charge
modulations. The native surface properties reflect a prevalent, anisotropic
disorder affecting 2D electron conduction. Importantly, the native lines are
orthogonal to the stripes theoretically proposed to explain high Landau level
transport anisotropies.

</DOC>
<DOC>
<DOCNO> 174565 </DOCNO>
Energy and angular momentum sharing in dissipative collisions


  Primary and secondary masses of heavy reaction products have been deduced
from kinematics and E-ToF measurements, respectively, for the direct and
reverse collisions of 93Nb and 116Sn at 25 AMeV. Light charged particles have
also been measured in coincidence with the heavy fragments.
  Direct experimental evidence of the correlation of energy-sharing with net
mass transfer has been found using the information from both the heavy
fragments and the light charged particles.
  The ratio of Hydrogen and Helium multiplicities points to a further
correlation of angular momentum sharing with net mass transfer.

</DOC>
<DOC>
<DOCNO> 8605 </DOCNO>
The interplay between shell effects and electron correlations in quantum


  We use the Path Integral Monte Carlo method to investigate the interplay
between shell effects and electron correlations in single quantum dots with up
to 12 electrons. By use of an energy estimator based on the hypervirial theorem
of Hirschfelder we study the energy contributions of different interaction
terms in detail. We discuss under which conditions the total spin of the
electrons is given by Hund's rule, and the temperature dependence of the
crystallization effects.

</DOC>
<DOC>
<DOCNO> 170577 </DOCNO>
Limits of control for quantum systems: kinematical bounds on the


  In this paper we investigate the limits of control for mixed-state quantum
systems. The constraint of unitary evolution for non-dissipative quantum
systems imposes kinematical bounds on the optimization of arbitrary
observables. We summarize our previous results on kinematical bounds and show
that these bounds are dynamically realizable for completely controllable
systems. Moreover, we establish improved bounds for certain partially
controllable systems. Finally, the question of dynamical realizability of the
bounds for arbitary partially controllable systems is shown to depend on the
accessible sets of the associated control system on the unitary group U(N) and
the results of a few control computations are discussed briefly.

</DOC>
<DOC>
<DOCNO> 178883 </DOCNO>
Angular Momenta of Even-Even Fragments in the Neutronless Fission of


  The recent advent of experimental techniques in which the dynamical
characteristics of fission fragments are determined more accurately, prompted
us to investigate the angular momentum acquired by fragments in a model which
describes the cold(neutronless) fission of $^{252}$Cf as the decay of a giant
nuclear molecule. The molecular configuration is a consequence of the interplay
between the attractive nuclear part and the repulsive Coulomb+nuclear forces.
The basic ideea of the present approach is to separate the radial(fission)
modes describing the decay of the molecule from the modes associated to
transversal vibrations(bending) of the fragments. The distance between the
centers of the two fragments is fixed by the requirement that the energy
released in the fission reaction $Q$, equals the sum of quantum zero-energies
of radial and transversal modes and the total excitation energy $E^*$. Using a
semiclassical coupled channel formalism we computed the additional angular
momenta acquired by the fragments during their post-scission motion, and found
that the Coulomb excitation accounts for less than 10% of the final spins.

</DOC>
<DOC>
<DOCNO> 99886 </DOCNO>
A Direct Integral Decomposition of the Wavelet Representation


  In this paper we use the concept of wavelet sets as introduced by X. Dai and
D. Larson, to decompose the wavelet representation of the discrete group
associated to an arbitrary $n \times n$ integer dilation matrix as a direct
integral of irreducible monomial representations. In so doing we generalize a
result of F. Martin and A. Valette in which they show that the wavelet
representation is weakly equivalent to the regular representation for the
Baumslag-Solitar groups.

</DOC>
<DOC>
<DOCNO> 71170 </DOCNO>
On nonleptonic decays of supermultiplets


  By describing strong interactions between hadrons via a relativistic
supermultiplet scheme and regarding weak interactions as a perturbation
thereof, we derive expressions for nonleptonic weak decay amplitudes in terms
of constituent quark masses and CKM angles, with no other parameters.
Application of this method leads to $\Delta I=1/2$ dominance in some
pseudoscalar meson decays if one scales down the couplings of heavy particles
by $\sqrt{M}$ mass factors, in keeping with heavy quark theory expectations.
However, certain B and D decay processes to kaons are badly predicted and point
to substantial soft gluon renormalization effects in W-quark interactions.

</DOC>
<DOC>
<DOCNO> 170768 </DOCNO>
Optimal conclusive teleportation of a d-dimensional unknown state


  We formulate a conclusive teleportation protocol for a system in
d-dimensional Hilbert space utilizing the positive operator valued measurement
at the sending station. The conclusive teleportation protocol ensures some
perfect teleportation events when the channel is only partially entangled, at
the expense of lowering the overall average fidelity. We find the change of the
fidelity as optimizing the conclusive teleportation events and discuss how much
information remains in the inconclusive parts of the teleportation.

</DOC>
<DOC>
<DOCNO> 85100 </DOCNO>
On physical foundations and observational effects of cosmic rotation


  An overview of the cosmological models with expansion, shear and rotation is
presented. Problems of the rotating models are discussed, their general
kinematic properties and dynamical realizations are described. A particular
attention is paid to the discussion of possible observational effects which
could be used to estimate or to put limits on the cosmic rotation.

</DOC>
<DOC>
<DOCNO> 178951 </DOCNO>
Macroconstraints from Microsymmetries of Macrosystems


  The dynamics governing the evolution of a many body system is constrained by
a nonabelian local symmetry. We obtain a general form of the global macroscopic
conditions assuring that at the microscopic level the evolution respects the
overall symmetry constraint. These conditions does not depend on detailed
dynamics of the system. It is shown that a nonabelian internal symmetry leads
to the new subsidiary condition imposed on the system. A structure of
constraints is analysed.

</DOC>
<DOC>
<DOCNO> 170070 </DOCNO>
Remote State Preparation


  Quantum teleportation uses prior entanglement and forward classical
communication to transmit one instance of an unknown quantum state. Remote
state preparation (RSP) has the same goal, but the sender knows classically
what state is to be transmitted. We show that the asymptotic classical
communication cost of RSP is one bit per qubit - half that of teleportation -
and becomes even less when transmitting part of a known entangled state. We
explore the tradeoff between entanglement and classical communication required
for RSP, and discuss RSP capacities of general quantum channels.

</DOC>
<DOC>
<DOCNO> 118295 </DOCNO>
Study of the Long Term Stability of two Anomalous X-ray Pulsars 4U


  We present new observations of two anomalous X-ray pulsars (AXP) 4U 0142+61
and 1E 1048.1-5937 made in 1998 with the ASCA. The energy spectra of these two
AXPs are found to consist of two components, a power-law and a blackbody
emission from the neutron star surface. These observations, when compared to
earlier ASCA observations in 1994 show remarkable stability in the intensity,
spectral shape and pulse profile. However, we find that the spin-down rate in
1E 1048.1-5937 is not constant. In this source, we have clearly identified
three epochs with spin-down rates different from each other and the average
value. This has very strong implications for the magnetar hypothesis of AXPs.
We also note that the spin-down rate and its variations in 1E 1048.1-5937 are
much larger than what can normally be produced by an accretion disk with very
low mass accretion rate corresponding to its low X-ray luminosity.

</DOC>
<DOC>
<DOCNO> 120376 </DOCNO>
Bardeen-Petterson Effect and Quasi-Periodic Oscillations in X-Ray


  The Bardeen-Petterson effect around a rapidly-rotating compact object causes
a tilted accretion disk to warp into the equatorial plane of the rotating body.
Viscous forces cause the accretion flow to divide into two distinct regions -
an inner aligned accretion disk and an outer tilted accretion disk. The
transition between these two occurs at a characteristic radius that depends on
the mass and angular momentum of the central object and possibly on the
accretion rate through the disk. We propose that accreting material passing
through the transition region may generate quasi-periodic brightness
oscillations (QPOs) such as have been observed in a number of X-ray binaries.
We show that this effect may be present in the black-hole X-ray binary GRO
J1655-40. We also argue that the QPO frequency range predicted by this model is
consistent with observed QPO frequencies in both black-hole and neutron-star
low-mass X-ray binaries.

</DOC>
<DOC>
<DOCNO> 68148 </DOCNO>
Nucleon magnetic moments in an extended chiral constituent quark model


  We present results for the nucleon magnetic moments in the context of an
extended chiral constituent quark model based on the mechanism of the Goldstone
boson exchange, as suggested by the spontaneous breaking of chiral symmetry in
QCD. The electromagnetic charge-current operator is consistently deduced from
the model Hamiltonian, which includes all force components for the
pseudoscalar, vector and scalar meson exchanges. Thus, the continuity equation
is satisfied for each piece of the interaction, avoiding the introduction of
any further parameter. A good agreement with experimental values is found. The
role of isoscalar two-body operators, not constrained by the continuity
equation, is also investigated.

</DOC>
<DOC>
<DOCNO> 119081 </DOCNO>
Accretion Disk Boundary Layers Around Neutron Stars: X-ray Production in


  We present solutions for the structure of the boundary layer where the
accretion disk meets the neutron star, which is expected to be the dominant
source of high-energy radiation in low-mass X-ray binaries which contain weakly
magnetized accreting neutron stars.
   We find that the main portion of the boundary layer gas is hot (> ~10^8 K),
low in density, radially and vertically extended, and optically thick to
scattering but optically thin to absorption. It will produce large X-ray
luminosity by Comptonization. Energy is transported inward by viscosity,
concentrating the energy dissipation in the dense, optically thick zone close
to the stellar surface. We explore the dependence of the boundary layer
structure on the mass accretion rate, the rotation rate of the star, the alpha
viscosity parameter and the viscosity prescription.
   Radiation pressure is the dominant source of pressure in the boundary layer;
the flux is close to the Eddington limiting flux even for luminosities well
below (~0.01 times) L(Edd). At luminosities near L(Edd), the boundary layer
expands radially, and has a radial extent larger than one stellar radius.
   Based on the temperatures and optical depths which characterize the boundary
layer, we expect that Comptonization will produce a power-law spectrum at low
source luminosities. At high luminosities, a Planckian spectrum will be
produced in the dense region where most of the energy is released, and modified
by Comptonization as the radiation propagates outward.

</DOC>
<DOC>
<DOCNO> 102882 </DOCNO>
Graded multiplicities in the exterior algebra


  We know the multiplicity of the adjoint representation of a semisimple Lie
algebra in its own exterior algebra, but how do its copies distribute
themselves between the exterior powers? The answer (the graded multiplicity) is
obtained with the aid of Macdonald polynomials.

</DOC>
<DOC>
<DOCNO> 71055 </DOCNO>
Hoelder Inequalities and QCD Sum-Rule Bounds on the Masses of Light


  QCD Laplace Sum-Rules must satisfy a fundamental Hoelder inequality if they
are to consistently represent an integrated hadronic spectral function. The
Laplace sum-rules of pion currents is shown to violate this inequality unless
the $u$ and $d$ quark masses are sufficiently large, placing a lower bound on
$m_u+m_d$, the SU(2)-invariant combination of the light-quark masses.

</DOC>
<DOC>
<DOCNO> 11534 </DOCNO>
Comparison of experimental data and theoretical calculations for


  The temperature dependences of the Hall coefficient and electrical
resistivity recently measured by Moser et al. [Phys. Rev. Lett. 84, 2674
(2000)] in the quasi-one-dimensional organic conductor (TMTSF)2PF6 are
quantitatively compared with our previous theoretical calculations [Synth. Met.
103, 2202 (1999); Eur. Phys. J. B 11, 385 (1999)]. We find a good agreement,
albeit not with a fully consistent set of parameters for the two quantities,
without appealing to the Luttinger liquid concept.

</DOC>
<DOC>
<DOCNO> 123011 </DOCNO>
First Results from the Anglo-Australian Planet Search - A Brown Dwarf


  We report results from the Anglo-Australian Planet Search -- a survey for
planets around 200 solar-type stars in the southern hemisphere, which is being
carried out on the 3.9m Anglo-Australian Telescope. Limiting Doppler precisions
of 3m/s have been demonstrated from the first 2.5 years of operation, making
this the highest precision planet search in the southern hemisphere. From these
data we report results for two new sub-stellar detections. The first is a "51
Peg"-like planet around the star HD179949 with Msin i = 0.84 Mjup. Photometric
study reveals this is not a transiting system. The second is a brown dwarf or
very low-mass star companion to HD164427 in an eccentric orbit with Msin i =
46Mjup. Hipparcos data indicate this latter object is unlikely to have a mass
greater than 0.18 Msol.

</DOC>
<DOC>
<DOCNO> 152084 </DOCNO>
Spinor Algebras


  We consider supersymmetry algebras in space-times with arbitrary signature
and minimal number of spinor generators. The interrelation between super
Poincar\'e and super conformal algebras is elucidated. Minimal super conformal
algebras are seen to have as bosonic part a classical semimisimple algebra
naturally associated to the spin group. This algebra, the Spin$(s,t)$-algebra,
depends both on the dimension and on the signature of space time. We also
consider maximal super conformal algebras, which are classified by the
orthosymplectic algebras.

</DOC>
<DOC>
<DOCNO> 102096 </DOCNO>
On 2D Euler Equations: Part I. On the Energy-Casimir Stabilities and The


  In this paper, we study a linearized two-dimensional Euler equation. This
equation decouples into infinitely many invariant subsystems. Each invariant
subsystem is shown to be a linear Hamiltonian system of infinite dimensions.
Another important invariant besides the Hamiltonian for each invariant
subsystem is found, and is utilized to prove an ``unstable disk theorem''
through a simple Energy-Casimir argument. The eigenvalues of the linear
Hamiltonian system are of four types: real pairs ($c,-c$), purely imaginary
pairs ($id,-id$), quadruples ($\pm c\pm id$), and zero eigenvalues. The
eigenvalues are computed through continued fractions. The spectral equation for
each invariant subsystem is a Poincar\'{e}-type difference equation, i.e. it
can be represented as the spectral equation of an infinite matrix operator, and
the infinite matrix operator is a sum of a constant-coefficient infinite matrix
operator and a compact infinite matrix operator. We have obtained a complete
spectral theory.

</DOC>
<DOC>
<DOCNO> 71218 </DOCNO>
Spectral Representation at Finite Temperature


  We present a derivation of the spectral representation for the complete
propagator of a scalar field in the real-time formulation of the quantum field
theory at finite temperature. The properties of the spectral function are
discussed. Two applications of this representation are then considered. One is
the solution of the Dyson equation for the propagator. The other is the
formulation of QCD sum rules at finite temperature.

</DOC>
<DOC>
<DOCNO> 68270 </DOCNO>
Supersymmetry Phenomenology


  This is a very pedagogical review of supersymmetry phenomenology, given at
ICTP Summer School in 1999, aimed mostly at students who had never studied
supersymmetry before. It starts with an analogy that the reason why
supersymmetry is needed is similar to the reason why the positron exists. It
introduces the construction of supersymmetric Lagrangians in a practical way.
The low-energy constraints, renormalization-group analyses, collider
phenomenology, and frameworks of mediating supersymmetry breaking are briefly
discussed.

</DOC>
<DOC>
<DOCNO> 71799 </DOCNO>
Initial Condition for QGP Evolution from NEXUS


  We recently proposed a new approach to high energy nuclear scattering, which
treats the initial stage of heavy ion collisions in a sophisticated way.
  We are able to calculate macroscopic quantities like energy density and
velocity flow at the end of this initial stage, after the two nuclei having
penetrated each other.
  In other words, we provide the initial conditions for a macroscopic treatment
of the second stage of the collision.
  We address in particular the question of how to incorporate the soft
component properly. We find almost perfect "Bjorken scaling": the rapidity
coincides with the space-time rapidity, whereas the transverse flow is
practically zero. The distribution of the energy density in the transverse
plane shows typically a very "bumpy" structure.

</DOC>
<DOC>
<DOCNO> 10106 </DOCNO>
Stability and noise in biochemical switches


  Many processes in biology, from the regulation of gene expression in bacteria
to memory in the brain, involve switches constructed from networks of
biochemical reactions. Crucial molecules are present in small numbers, raising
questions about noise and stability. Analysis of noise in simple reaction
schemes indicates that switches stable for years and switchable in milliseconds
can be built from fewer than one hundred molecules. Prospects for direct tests
of this prediction, as well as implications, are discussed.

</DOC>
<DOC>
<DOCNO> 99298 </DOCNO>
Statistical Mechanics of the Periodic Camassa-Holm Equation


  The paper has been withdrawn

</DOC>
<DOC>
<DOCNO> 119128 </DOCNO>
New challenges for Adaptive Optics: Extremely Large Telescopes


  The performance of an adaptive optics (AO) system on a 100m diameter ground
based telescope working in the visible range of the spectrum is computed using
an analytical approach. The target Strehl ratio of 60% is achieved at 0.5um
with a limiting magnitude of the AO guide source near R~10, at the cost of an
extremely low sky coverage. To alleviate this problem, the concept of
tomographic wavefront sensing in a wider field of view using either natural
guide stars (NGS) or laser guide stars (LGS) is investigated. These methods use
3 or 4 reference sources and up to 3 deformable mirrors, which increase up to
8-fold the corrected field size (up to 60\arcsec at 0.5 um). Operation with
multiple NGS is limited to the infrared (in the J band this approach yields a
sky coverage of 50% with a Strehl ratio of 0.2). The option of open-loop
wavefront correction in the visible using several bright NGS is discussed. The
LGS approach involves the use of a faint (R ~22) NGS for low-order correction,
which results in a sky coverage of 40% at the Galactic poles in the visible.

</DOC>
<DOC>
<DOCNO> 10487 </DOCNO>
Metamagnetism in one dimensional systems with edge sharing CuO polihedra


  We study a Heisenberg chain with nearest-neighbor (NN) J1 and next-NN J2
exchange interactions with anisotropies Delta_1 and Delta_2 respectively. We
investigate by analytical and numerical methods the region of parameters for
which there is a jump in the magnetization M as a function of magnetic field B.
Some materials with edge sharing CuO polihedra are candidates to show an abrupt
change in M(B).

</DOC>
<DOC>
<DOCNO> 120818 </DOCNO>
Contemporaneous Observations of Direct and Raman Scattered O VI in


  Symbiotic stars are binary systems consisting of a hot star, typically a
white dwarf, and a cool giant companion. The wind from the cool star is ionized
by the radiation from the hot star, resulting in the characteristic combination
of sharp nebular emission lines and stellar molecular absorption lines in the
optical spectrum. Most of the emission lines are readily identifiable with
common ions. However, two strong, broad emission lines at $\lambda\lambda$
6825, 7082 defied identification with known atoms and ions. In 1989 Schmid made
the case that these long unidentified emission lines resulted from the Raman
scattering of the O VI resonance photons at $\lambda\lambda$ 1032, 1038 by
neutral hydrogen.
  We present contemporaneous far-UV and optical observations of direct and
Raman scattered O VI lines for nine symbiotic stars obtained with the Hopkins
Ultraviolet Telescope (Astro-2) and various ground-based telescopes. The O VI
emission lines are present in every instance in which the $\lambda\lambda$
6825, 7082 lines are present in support of the Schmid Raman scattering model.
We calculate scattering efficiencies and interpret the results in terms of the
Raman models. Additionally, we measure the flux of the Fe II fluorescence line
at $\lambda$1776, which is excited by the O VI line at $\lambda$1032, and
calculate the first estimates of the conversion efficiencies of this process.

</DOC>
<DOC>
<DOCNO> 151705 </DOCNO>
The moduli space of two U(1) instantons on noncommutative $R^4$ and


  We employ the ADHM method to derive the moduli space of two instantons in
U(1) gauge theory on a noncommutative space. We show by an explicit
hyperK\"ahler quotient construction that the relative metric of the moduli
space of two instantons on $R^4$ is the Eguchi-Hanson metric and find a unique
threshold bound state. For two instantons on $R^3\times S^1$, otherwise known
as calorons, we give the asymptotic metric and conjecture a completion. We
further discuss the relationship of caloron moduli spaces of A, D and E groups
to the Coulomb branches of three dimensional gauge theory. In particular, we
show that the Coulomb branch of SU(2) gauge group with a single massive adjoint
hypermultiplet coincides with the above two caloron moduli space.

</DOC>
<DOC>
<DOCNO> 101217 </DOCNO>
Decomposition of Marsden-Weinstein reductions for representations of


  We decompose the Marsden-Weinstein reductions for the moment map associated
to representations of a quiver. The decomposition involves symmetric products
of deformations of Kleinian singularities, as well as other terms. As a
corollary we deduce that the Marsden-Weinstein reductions are irreducible
varieties.

</DOC>
<DOC>
<DOCNO> 83264 </DOCNO>
Light Affine Logic (Proof Nets, Programming Notation, P-Time Correctness


  This paper is a structured introduction to Light Affine Logic, and to its
intuitionistic fragment. Light Affine Logic has a polynomially costing cut
elimination (P-Time correctness), and encodes all P-Time Turing machines
(P-Time completeness). P-Time correctness is proved by introducing the Proof
nets for Intuitionistic Light Affine Logic. P-Time completeness is demonstrated
in full details thanks to a very compact program notation. On one side, the
proof of P-Time correctness describes how the complexity of cut elimination is
controlled, thanks to a suitable cut elimination strategy that exploits
structural properties of the Proof nets. This allows to have a good catch on
the meaning of the ``paragraph'' modality, which is a peculiarity of light
logics. On the other side, the proof of P-Time completeness, together with a
lot of programming examples, gives a flavor of the non trivial task of
programming with resource limitations, using Intuitionistic Light Affine Logic
derivations as programs.

</DOC>
<DOC>
<DOCNO> 12633 </DOCNO>
Hydrodynamic Models for Heavy-Ion Collisions, and beyond


  A generic property of a first-order phase transition in equilibrium, and in
the limit of large entropy per unit of conserved charge, is the smallness of
the isentropic speed of sound in the ``mixed phase''. A specific prediction is
that this should lead to a non-isotropic momentum distribution of nucleons in
the reaction plane (for energies around 40 AGeV in our model calculation). On
the other hand, we show that from present effective theories for low-energy QCD
one does not expect the thermal transition rate between various states of the
effective potential to be much larger than the expansion rate, questioning the
applicability of the idealized Maxwell/Gibbs construction. Experimental data
could soon provide essential information on the dynamics of the phase
transition.

</DOC>
<DOC>
<DOCNO> 11915 </DOCNO>
Width and Magnetic Field Dependence of Transition Temperature in


  We calculate the transition temperature in ultranarrow superconducting wires
as a function of wire width, resistance and applied magnetic field. We compare
the results of first-order perturbation theory and the non-perturbative
resummation technique developed by Oreg and Finkel'stein. The latter technique
is found to be superior as it is valid even in the strong disorder limit. In
both cases the predicted additional suppression of the transition temperature
due to the reduced dimensionality is strongly dependent upon the boundary
conditions used. When we use the correct (zero-gradient) boundary conditions,
we find that theory and experiment are consistent, although more experimental
data is required to verify this systematically. We calculate the magnetic field
dependence of the transition temperature for different wire widths and
resistances in the hope that this will be measured in future experiments. The
predicted results have a rich structure - in particular we find a dimensional
crossover which can be tuned by varying either the width of the wire or its
resistance per square.

</DOC>
<DOC>
<DOCNO> 72239 </DOCNO>
An Exact Solution of BPS Junctions and Its Properties


  We have obtained an exact solution for the BPS domain wall junction for a N=1
supersymmetric theory in four dimensions and studied its properties. The model
is a simplified version of the N=2 SU(2) gauge theory with N_f=1 broken to N=1
by the mass of the adjoint chiral superfield. We define mode equations and
demonstrate explicitly that fermion and boson with the same mass have to come
in pairs except massless modes. We work out explicitly massless Nambu-Goldstone
(NG) modes on the BPS domain wall junction. We find that their wave functions
extend along the wall to infinity (not localized) and are not normalizable. It
is argued that this feature is a generic phenomenon of NG modes on domain wall
junctions in the bulk flat space in any dimensions. NG fermions exhibit a
chiral structure in accordance with unitary representations of (1, 0)
supersymmetry algebra where fermion and boson with the same mass come in pairs
except massless modes which can appear singly.

</DOC>
<DOC>
<DOCNO> 101426 </DOCNO>
Cellular Structures determined by Polygons and Trees


  The polytope structure of the associahedron is decomposed into two
categories, types and classes. The classification of types is related to
integer partitions, whereas the classes present a new combinatorial problem. We
solve this and incorporate the results into properties of the real moduli space
of Riemann spheres. Connections are discussed with relation to classic
combinatorial problems as well as to other sciences.

</DOC>
<DOC>
<DOCNO> 100922 </DOCNO>
Spectral inclusion and spectral exactness for singular non-selfadjoint


  We consider the effect of regularization by interval truncation on the
spectrum of a singular non-selfadjoint Sturm-Liouville operator. We present
results on spectral inclusion and spectral exactness for the cases where the
singularity is in Sims Case II or Sims Case III. For Sims Case I we present a
test for spectral inexactness, which can be used to detect when the interval
truncation process is generating spurious eigenvalues. Numerical results
illustrate the effectiveness of this test.

</DOC>
<DOC>
<DOCNO> 84562 </DOCNO>
Integrable spherically symmetric p-brane models associated with Lie


  A classical model of gravity theory with several dilatonic scalar fields and
differential forms admitting an interpretation in terms of intersecting
p-branes is studied in (pseudo)-Riemannian space-time $M =R_+\times
S^{d_0}\times R_t\times M_2^{d_2}...\times M_n^{d_n}$ of dimension D. The
equations of motion of the model are reduced to the Euler-Lagrange equations
for the so-called pseudo-Euclidean Toda-like system. We suppose that the
characteristic vectors related to the configuration of p-branes and their
couplings to the dilatonic scalar fields may be interpreted as the root vectors
of a Lie algebra of the types $A_r, B_r, C_r$. In this case the model is
reducible to one of the open Toda chain's algebraic generalization and is
completely integrable by the known methods. The corresponding general solutions
are presented in explicit form. The particular exact solution describing a
class of nonextremal black holes is obtained and analyzed.

</DOC>
<DOC>
<DOCNO> 12433 </DOCNO>
Small Cycles in Small Worlds


  We characterize the distributions of short cycles in a large metabolic
network previously shown to have small world characteristics and a power law
degree distribution. Compared with three classes of random networks, including
Erdoes-Renyi random graphs and synthetic small world networks of the same
connectivity, the metabolic network has a particularly large number of
triangles and a deficit in large cycles. Short cycles reduce the length of
detours when a connection is clipped, so we propose that long cycles in
metabolism may have been selected against in order to shorten transition times
and reduce the likelihood of oscillations in response to external
perturbations.

</DOC>
<DOC>
<DOCNO> 122531 </DOCNO>
The Infrared Spectral Energy Distribution of Normal Star-Forming


  We present a new phenomenological model for the spectral energy distribution
of normal star-forming galaxies between 3 and 1100 microns. A sequence of
realistic galaxy spectra are constructed from a family of dust emission curves
assuming a power law distribution of dust mass over a wide range of
interstellar radiation fields. For each interstellar radiation field heating
intensity we combine emission curves for large and very small grains and
aromatic feature carriers. The model is constrained by IRAS and ISOCAM
broadband photometric and ISOPHOT spectrophotometric observations for our
sample of 69 normal galaxies; the model reproduces well the empirical spectra
and infrared color trends. These model spectra allow us to determine the
infrared energy budget for normal galaxies, and in particular to translate
far-infrared fluxes into total (bolometric) infrared fluxes. The 20 to 42
micron range appears to show the most significant growth in relative terms as
the activity level increases, suggesting that the 20-42 micron continuum may be
the best dust emission tracer of current star formation in galaxies. The
redshift dependence of infrared color-color diagrams and the far-infrared to
radio correlation for galaxies are also explored.

</DOC>
<DOC>
<DOCNO> 117283 </DOCNO>
Levels of Reality as Source of Quantum Indeterminacy


  We show that the notion of "levels of Reality" introduced by Werner
Heisenberg in his "Manuscript of 1942" (1984) and by myself (1983-1985) could
explain the quantum indeterminacy. General epistemological implications of this
notion are also studied.

</DOC>
<DOC>
<DOCNO> 69639 </DOCNO>
QCD improved parton distribution functions of ${\mathbf{\gamma^*_L}}$


  QCD corrections to the QED formula for parton distribution functions of the
longitudinal virtual photon are derived in the leading--logarithmic
approximation. It is shown that the resulting PDF satisfy the same homogeneous
evolution equations as those of hadrons, but contrary to the latter are
perturbatively calculable. Properties of these distribution functions are
discussed and their phenomenological consequences outlined.

</DOC>
<DOC>
<DOCNO> 151551 </DOCNO>
Ramond-Ramond Flux Stabilization of D-Branes


  In AdS_n x S^m threaded by N-units of Ramond-Ramond flux, the dynamics of a
Dm-brane wrapped on S^{m-1} embedded in S^m is investigated. Under the
condition that flux of the dual gauge field on the D-brane worldvolume is
quantized integrally, It is found that the wrapped D-brane is stable both
locally and globally and, on AdS_n, behaves effectively as a fundamental
string. It is also claimed that the semi-infinite partially wrapped D-brane
`lasso' around the S^m.

</DOC>
<DOC>
<DOCNO> 10629 </DOCNO>
Phase Diagram Structure of the Harper Map


  This paper has been withdrawn by the authors due to several major changes in
concepts and results. New version will follow briefly as a new e-print.

</DOC>
<DOC>
<DOCNO> 151870 </DOCNO>
Localization of Equivariant Cohomology - Introductory and Expository


  We present a brief introduction to the Berline-Vergne localization formula
which expresses the integral of an equivariant cohomology class as a sum over
zeros of a vector field to which that class is related.

</DOC>
<DOC>
<DOCNO> 120563 </DOCNO>
Feedback from Protostellar Outflows in Star and Star Cluster Formation


  Magnetic stresses collimate protostellar winds into a common distribution of
force with angle. Sweeping into the ambient medium, such winds drive bipolar
molecular outflows whose properties are insensitive to the distribution of
ambient gas and to the details of how the wind is launched, and how its
intensity varies over time. Moreover, these properties are in accord with the
commonly observed features of outflows.
  This model is simple enough to permit a quantitative study of the feedback
effects from low-mass star formation. It predicts the rate at which
star-forming gas is ejected by winds, and hence the efficiency with which stars
form. Applied to individual star formation, it relates the stellar initial mass
function to the distribution of pre-stellar cores. Applied to cluster
formation, it indicates whether the resulting stellar system will remain
gravitationally bound.
  Using the energy injection and mass ejection implied by this model, we
investigate the dynamical evolution of a molecular clump as a stellar cluster
forms within it. This depends critically on the rate at which turbulence
decays: it may involve equilibrium star formation (slow decay), overstable
oscillations, or collapse (fast decay).

</DOC>
<DOC>
<DOCNO> 11977 </DOCNO>
Oscillations of the superconducting order parameter in a ferromagnet


  Planar tunneling spectroscopy reveals damped oscillations of the
superconducting order parameter induced into a ferromagnetic thin film by the
proximity effect. The oscillations are due to the finite momentum transfer
provided to Cooper pairs by the splitting of the spin up and down bands in the
ferromagnet. As a consequence, for negative values of the superconducting order
parameter the tunneling spectra are capsized ("$\pi$-state"). The oscillations'
damping and period are set by the same length scale, which depends on the spin
polarization.

</DOC>
<DOC>
<DOCNO> 8970 </DOCNO>
Levy distribution in half space based on nonextensive statistical


  Probability distributions defined on the half space are known to be quite
different from those in the full space. Here, a nonextensive entropic treatment
is presented for the half space in an analytic and self-consistent way. In this
development, the ordinary first moment of the random variable X is divergent in
contrast to the case of the full space. A general (nu)-th moment of X is
considered as a constraint in the principle of maximum Tsallis entropy. The
infinite divisibility of the distribution with an arbitrary (nu) larger than
zero and convergence of its N-fold convolution to the exact Levy-stable
distribution is discussed in detail. A feature of this derivation is that the
Levy index is related to both the values of (nu) and the index of
nonextensivity.

</DOC>
<DOC>
<DOCNO> 12017 </DOCNO>
Fractal Growth from Local Instabilities


  We study, both with numerical simulations and theoretical methods, a cellular
automata model for continuum equations describing growth processes in the
presence of an external flux of particles. As a result of local instabilities
we find a fractal regime of growth for small external fluxes. The growing tip
is selected with probability proportional to the curvature in the point. A
parameter $p$ gives the probability of lateral growth on the tip. The value of
$p$ determines the fractal dimension of the aggregate. Furthermore, for each
value of $p$ a cross-over between two different fractal dimensions is observed.
Instead, the roughness exponent $\chi$ of the aggregates does not depend on $p$
($\chi \simeq 0.5$). Fixed scale transformation approach is applied to compute
theoretically the fractal dimension for one of the branches of the structure.

</DOC>
<DOC>
<DOCNO> 121273 </DOCNO>
Modelling Tools: Population and Evolutionary Synthesis


  I review the basic concepts for the spectrophotometric and chemical evolution
of galaxies, contrast various approaches and discuss their respective
advantages and shortcomings, both for the interpretation of nearby and high
redshift galaxies. Focus is on recent attempts to include gas and dust into
galaxy evolution models and to account for the links among stars, gas and dust.
Chemically consistent models are described that try to cope with extended
stellar metallicity distributions observed in local galaxies and with subsolar
abundances in young galaxies.

</DOC>
<DOC>
<DOCNO> 7757 </DOCNO>
Thermodynamics and dielectric anomalies of DMAAS and DMAGaS crystals in


  A simple description of thermodynamics of DMAAS and DMAGaS ferroelectric
crystals by means of Landau expansion is proposed. Conditions of occurrence of
phase transitions are established and their temperatures are obtained. The
influence of external hydrostatic pressure on phase transitions is described.
The temperature behaviour of dielectric susceptibility components and their
anomalies in the vicinity of phase transition points are investigated. Obtained
results are compared with experimental data.

</DOC>
<DOC>
<DOCNO> 8442 </DOCNO>
Delocalization in the Anderson model due to a local measurement


  We study a one-dimensional Anderson model in which one site interacts with a
detector monitoring the occupation of that site. We demonstrate that such an
interaction, no matter how weak, leads to total delocalization of the Anderson
model, and we discuss the experimental consequences

</DOC>
<DOC>
<DOCNO> 116540 </DOCNO>
Design and Simulation of a High Frequency High Power Rf Extraction


  We consider the use of a dielectric-loaded structure to extract rf energy
from a high current electron drive beam as a power source for a high energy
two-beam accelerator. This represents an alternative technique which we show to
have some significant advantages over the use of the currently proposed
corrugated metal structures as power extraction devices. We discuss a
particular design that will extract high power rf (0.1 -- 1 GW) from a high
current drive beam. Rf generation and transport in this class of devices have
already been demonstrated at lower frequencies. We discuss the design
parameters for 15 and 30 GHz dielectric transfer structures and some possible
experiments.

</DOC>
<DOC>
<DOCNO> 70045 </DOCNO>
Manifestation of Jet Quenching in the Total Transverse Energy


  In the framework of the HIJING model global characteristics of nucleus-
nucleus collisions are studied for a Large Hadron Collider energy scale. An
interesting model prediction is the presence of a central bump over a
pseudorapidity plateau of a total transverse energy distribution. The bump is
induced by a jet quenching effect in a dense nuclear matter. It is shown that
on a wide acceptance calorimeter with a pseudorapidity coverage
 -5 < \eta < 5 allow to obtain experimental confirmation of such an effect.

</DOC>
<DOC>
<DOCNO> 11522 </DOCNO>
Hall effect and inter-chain magneto-optical properties of coupled


  We consider the Hall effect in a system of weakly coupled Luttinger chains.
We obtain the full conductivity tensor in the absence of dissipation along the
chains. We show that while the dependence of the Hall and transverse
conductivities on temperature and frequency are affected by the Luttinger
interaction very strongly, the Hall resistivity is given by a simple formula
corresponding to the noninteracting fermions. We compute the frequency,
temperature and field dependence of the transverse conductivity. Consequences
for the quasi-one-dimensional organic conductors are discussed.

</DOC>
<DOC>
<DOCNO> 121711 </DOCNO>
Planck LFI: Comparison Between Galaxy Straylight Contamination and other


  The straylight contamination due to the Galactic emission (GSC, Galaxy
Straylight Contamination) entering at large angles from the antenna centre
direction may be one of the most critical sources of systematic effects in
observations of the cosmic microwave background (CMB) anisotropies by future
satellite missions like {\sc Planck} and MAP. We describe here different
methods to evaluate the impact of this effect and compare it with other
systematics of instrumental and astrophysical origin. The contributions within
few degrees from the beam centre dominate the GSC near the Galaxy plane. The
antenna sidelobes at intermediate and large angles from the beam centre
dominate the GSC at medium and high Galactic latitudes. We find a GSC peak at
$\sim 15\mu$K and a GSC angular power spectrum above that of the white noise
for multipoles $\ell \lsim 10$ albeit smaller than that of CMB anisotropies by
a factor larger than $\sim 10$. Although the GSC is largest at low Galactic
latitudes, the contamination produced by far pattern features at medium and
high Galactic latitudes, peaking at $\sim 4\mu$K, has to be carefully
investigated, because the combination of low amplitude of Galaxy emission in
those regions with the extremely good nominal {\sc Planck} sensitivity
naturally makes high Galactic latitude areas the targets for unprecedentedly
precise estimation of cosmological CMB anisotropy.

</DOC>
<DOC>
<DOCNO> 7766 </DOCNO>
Universality classes of driven lattice gases


  Motivated by some recent criticisms to our alternative Langevin equation for
driven lattice gases (DLG) under an infinitely large driving field, we revisit
the derivation of such an equation, and test its validity. As a result, an
additional term, coming from a careful consideration of entropic contributions,
is added to the equation. This term heals all the recently reported generic
infrared singularities.
 The emerging equation is then identical to that describing randomly driven
diffusive systems. This fact confirms our claim that the infinite driving limit
is singular, and that the main relevant ingredient determining the critical
behavior of the DLG in this limit is the anisotropy and not the presence of a
current. Different aspects of our picture are discussed, and it is concluded
that it constitutes a very plausible scenario to rationalize the critical
behavior of the DLG and variants of it.

</DOC>
<DOC>
<DOCNO> 71179 </DOCNO>
Bounds on Extra Dimensions from Binary Pulsars


  Evidence for gravitational radiation from binary pulsars places constraints
on properties of ``large'' extra dimensions. The size of these extra dimensions
must exceed about 37 AU for gravitational radiation to be emitted.

</DOC>
<DOC>
<DOCNO> 80722 </DOCNO>
Chiral Symmetry, Quark Mass, and Scaling of the Overlap Fermions


  The chiral symmetry relation and scaling of the overlap fermions are studied
numerically on the quenched lattices at 3 couplings with about the same
physical volume. We find that the generalized Gell-Mann-Oakes-Renner relation
is satisfied to better than 1% down to the smallest quark mass at $m_0a =
0.006$. We also obtain the quark mass from the PCAC relation and the
pseudoscalar masses. The renormalization group invariant quark mass is shown to
be fairly independent of scale. The $\pi$ and $\rho$ masses at a fixed
$m_{\pi}/m_{\rho}$ ratio indicate small $O(a^2)$ corrections. It is found that
the critical slowing down sets in abruptly at a very small quark mass close to
those of the physical u and d quarks.

</DOC>
<DOC>
<DOCNO> 71306 </DOCNO>
Phenomenology for pp->pp pi0


  We show that it is possible to empirically partition the differential cross
section for pp->pp pi0 into initial singlet and triplet differential cross
sections in a model independent way which can be implemented using the existing
technological capabilities at the PINTEX facility to study the reaction
employing polarized beam or polarized target or both simultaneously.

</DOC>
<DOC>
<DOCNO> 118710 </DOCNO>
Perspective of long baseline interferometry


  This article is a sort of sequel of the earlier extensive review by Saha
(1999a) where emphasis was laid down on the ground based single aperture, as
well as on the working long baseline optical interferometers (LBI) situated at
the various observatories across the globe that are producing a large amount of
astronomical results. Since the future of high resolution astronomy lies with
the new generation of arrays, the numerous technical challenges of developing
such systems are addressed indicating the current trends and the path to future
progress in interferometry. The new generation interferometers such as Palomar
testbed interferometer (PTI), Navy prototype optical interferometer (NPOI),
Keck interferometer, Very large telescope interferometer (VLTI), Center for
high angular resolution astronomy (CHARA) array, Optical very large array
(OVLA), Mitaka optical infrared arrays (MIRA), etc., are being developed. A few
of them, viz., PTI, NPOI, IOTA are producing results. Among the working
interferometers that have been described earlier by Saha (1999a), the expansion
of the Grand interf\'erom\`etre \`a deux (two) t\'elescopes (GI2T), Infrared
and optical telescope array (IOTA) are in progress. The current status of all
these interferometers stated above are enumerated. The data analysis being
carried out using the working interferometers are also described. The space
interferometry programmes are advancing very fast. Among the notable ones are
the Space technology 3 (ST3), Space interferometry mission (SIM), and Darwin;
they have already received funds. The technical details of these
interferometers and their objectives are highlighted.

</DOC>
<DOC>
<DOCNO> 119507 </DOCNO>
Variability of NGC 4051 and the Nature of Narrow-Line Seyfert 1 Galaxies


  We report on a three-year program of coordinated X-ray and optical monitoring
of the Narrow-Line Seyfert 1 galaxy NGC 4051. The rapid continuum variations
observed in the X-ray spectra are not detected in the optical, although the
X-ray and optical continuum fluxes are correlated on time scales of many weeks
and longer. Variations in the flux of the broad H-beta line are found to lag
behind the optical continuum variations by approximately 6 days (with an
uncertainty of 2-3 days), and combining this with the line width yields a
virial mass estimate of about 1.1e6 solar masses, at the very low end of the
distribution of AGN masses measured by line reverberation. Strong variability
of He II lambda 4686 is also detected, and the response time measured is
similar to that of H-beta, but with a much larger uncertainty. The He II lambda
4686 line is almost five times broader than H-beta, and it is strongly blueward
asymmetric, as are the high-ionization UV lines recorded in archive spectra of
NGC 4051. The data are consistent with the Balmer lines arising in a
low-inclination (nearly face-on) disk-like configuration, and the
high-ionization lines arising in an outflowing wind, of which we observe
preferentially the near side. During the third year of monitoring, both the
X-ray continuum and the He II lambda 4686 line went into extremely low states,
although the optical continuum and the H-beta broad line were both still
present and variable. We suggest that the inner part of the accretion disk may
have gone into an advection-dominated state, yielding little radiation from the
hotter inner disk.

</DOC>
<DOC>
<DOCNO> 67665 </DOCNO>
Baryon number non-conservation and phase transitions at preheating


  Certain inflation models undergo pre-heating, in which inflaton oscillations
can drive parametric resonance instabilities. We discuss several phenomena
stemming from such instabilities, especially in weak-scale models; generically,
these involve energizing a resonant system so that it can evade tunneling by
crossing barriers classically. One possibility is a spontaneous change of phase
from a lower-energy vacuum state to one of higher energy, as exemplified by an
asymmetric double-well potential with different masses in each well. If the
lower well is in resonance with oscillations of the potential, a system can be
driven resonantly to the upper well and stay there (except for tunneling) if
the upper well is not resonant. Another example occurs in hybrid inflation
models where the Higgs field is resonant; the Higgs oscillations can be
transferred to electroweak (EW) gauge potentials, leading to rapid transitions
over sphaleron barriers and consequent B+L violation. Given an appropriate
CP-violating seed, we find that preheating can drive a time-varying condensate
of Chern-Simons number over large spatial scales; this condensate evolves by
oscillation as well as decay into modes with shorter spatial gradients,
eventually ending up as a condensate of sphalerons. We study these examples
numerically and to some extent analytically. The emphasis in the present paper
is on the generic mechanisms, and not on specific preheating models; these will
be discussed in a later paper.

</DOC>
<DOC>
<DOCNO> 11826 </DOCNO>
Investigation of the Two-Particle-Self-Consistent Theory for the


  The two-particle-self-consistent theory is applied to the single-impurity
Anderson model. It is found that it cannot reproduce the small energy scale in
the strong correlation limit. A modified scheme to overcome this difficulty is
proposed by introducing an appropriate vertex correction explicitly. Using the
same vertex correction, the self-energy is investigated, and it is found that
under certain assumptions it reproduces the result of the modified perturbation
theory which interpolates the weak and the strong correlation limits.

</DOC>
<DOC>
<DOCNO> 13503 </DOCNO>
Josephson Coupling through a Quantum Dot


  We derive, via fourth order perturbation theory, an expression for the
Josephson current through a gated interacting quantum dot. We analyze our
expression for two different models of the superconductor-dot-superconductor
(SDS) system. When the matrix elements connecting dot and leads are featureless
constants, we compute the Josephson coupling J_c as a function of the gate
voltage and Coulomb interaction. In the diffusive dot limit, we compute the
probability distribution P(J_c) of Josephson couplings. In both cases, pi
junction behavior (J_c < 0) is possible, and is not simply dependent on the
parity of the dot occupancy.

</DOC>
<DOC>
<DOCNO> 80584 </DOCNO>
The derivation of the dual superconductor theory from the Maximal Center


  We consider the Center projected SU(3) gluodynamics and rewrite it as a dual
superconductor theory. The center monopole field plays the role of Higgs field
in the dual superconductor theory.
  The center monopole creation operator is constructed.

</DOC>
<DOC>
<DOCNO> 170514 </DOCNO>
Bounds on relative entropy of entanglement for multi-party systems


  We present upper and lower bounds to the relative entropy of entanglement of
multi-party systems in terms of the bi-partite entanglements of formation and
distillation and entropies of various subsystems. We point out implications of
our results to the local reversible convertibility of multi-party pure states
and discuss their physical basis in terms of deleting of information.

</DOC>
<DOC>
<DOCNO> 71309 </DOCNO>
Inflationary Initial Conditions Consistent with Causality


  The initial condition problem of inflation is examined from the perspective
of both spacetime embedding and scalar field dynamics. The spacetime embedding
problem is solved for arbitrary initial spatial curvature Omega, which
generalizes previous works that primarily treat the flat case Omega=1. Scalar
field dynamics that is consistent with the embedding constraints are examined,
with the additional treatment of damping effects. The effects of
inhomogeneities on the embedding problem also are considered. A category of
initial conditions are identified that are not acausal and can develop into an
inflationary regime.

</DOC>
<DOC>
<DOCNO> 101465 </DOCNO>
Symmetry classes of alternating-sign matrices under one roof


  In a previous article [math.CO/9712207], we derived the alternating-sign
matrix (ASM) theorem from the Izergin-Korepin determinant for a partition
function for square ice with domain wall boundary. Here we show that the same
argument enumerates three other symmetry classes of alternating-sign matrices:
VSASMs (vertically symmetric ASMs), even HTSASMs (half-turn-symmetric ASMs),
and even QTSASMs (quarter-turn-symmetric ASMs). The VSASM enumeration was
conjectured by Mills; the others by Robbins [math.CO/0008045]. We introduce
several new types of ASMs: UASMs (ASMs with a U-turn side), UUASMs (two U-turn
sides), OSASMs (off-diagonally symmetric ASMs), OOSASMs (off-diagonally,
off-antidiagonally symmetric), and UOSASMs (off-diagonally symmetric with
U-turn sides). UASMs generalize VSASMs, while UUASMs generalize VHSASMs
(vertically and horizontally symmetric ASMs) and another new class, VHPASMs
(vertically and horizontally perverse). OSASMs, OOSASMs, and UOSASMs are
related to the remaining symmetry classes of ASMs, namely DSASMs (diagonally
symmetric), DASASMs (diagonally, anti-diagonally symmetric), and TSASMs
(totally symmetric ASMs). We enumerate several of these new classes, and we
provide several 2-enumerations and 3-enumerations.
  Our main technical tool is a set of multi-parameter determinant and Pfaffian
formulas generalizing the Izergin-Korepin determinant for ASMs and the Tsuchiya
determinant for UASMs [solv-int/9804010]. We evaluate specializations of the
determinants and Pfaffians using the factor exhaustion method.

</DOC>
<DOC>
<DOCNO> 85583 </DOCNO>
Gravitoelectromagnetism and the Integral Formulation of MAxwell's


  The integral formulation of Maxwell's equations expressed in terms of an
arbitrary observer family in a curved spacetime is developed and used to
clarify the meaning of the lines of force associated with observer-dependent
electric and magnetic fields.

</DOC>
<DOC>
<DOCNO> 12182 </DOCNO>
Replica-Exchange Simulated Tempering Method for Simulations of


  We propose a new method for the determination of the weight factor for the
simulated tempering method. In this method a short replica-exchange simulation
is performed and the simulated tempering weight factor is obtained by the
multiple-histogram reweighting techniques. The new algorithm is particularly
useful for studying frustrated systems with rough energy landscape where the
determination of the simulated tempering weight factor by the usual iterative
process becomes very difficult. The effectiveness of the method is illustrated
by taking an example for protein folding.

</DOC>
<DOC>
<DOCNO> 12238 </DOCNO>
Spatial Persistence of Fluctuating Interfaces


  We show that the probability, P_0(l), that the height of a fluctuating
(d+1)-dimensional interface in its steady state stays above its initial value
up to a distance l, along any linear cut in the d-dimensional space, decays as
P_0(l) \sim l^(-\theta). Here \theta is a `spatial' persistence exponent, and
takes different values, \theta_s or \theta_0, depending on how the point from
which l is measured is specified. While \theta_s is related to fractional
Brownian motion, and can be determined exactly, \theta_0 is non-trivial even
for Gaussian interfaces.

</DOC>
<DOC>
<DOCNO> 9203 </DOCNO>
Cluster Monte Carlo study of multi-component fluids of the


  Phase transitions of fluid mixtures of the type introduced by Stillinger and
Helfand are studied using a continuum version of the invaded cluster algorithm.
Particles of the same species do not interact, but particles of different types
interact with each other via a repulsive potential. Examples of interactions
include the Gaussian molecule potential and a repulsive step potential.
Accurate values of the critical density, fugacity and magnetic exponent are
found in two and three dimensions for the two-species model. The effect of
varying the number of species and of introducing quenched impurities is also
investigated. In all the cases studied, mixtures of $q$-species are found to
have properties similar to $q$-state Potts models.

</DOC>
<DOC>
<DOCNO> 9053 </DOCNO>
Non-equilibrium supercurrent through mesoscopic ferromagnetic weak links


  We consider a mesoscopic normal metal, where the spin degeneracy is lifted by
a ferromagnetic exchange field or Zeeman splitting, coupled to two
superconducting reservoirs. As a function of the exchange field or the distance
between the reservoirs, the supercurrent through this device oscillates with an
exponentially decreasing envelope. This phenomenon is similar to the tuning of
a supercurrent by a non-equilibrium quasiparticle distribution between two
voltage-biased reservoirs. We propose a device combining the exchange field and
non-equilibrium effects, which allows us to observe a range of novel phenomena.
For instance, part of the field-suppressed supercurrent can be recovered by a
voltage between the additional probes.

</DOC>
<DOC>
<DOCNO> 8484 </DOCNO>
Solution of the Schr\"odinger Equation for Quantum Dot Lattices with


  The Schr\"odinger equation for quantum dot lattices with non-cubic,
non-Bravais lattices built up from elliptical dots is investigated. The Coulomb
interaction between the dots is considered in dipole approximation. Then only
the center of mass (c.m.) coordinates of different dots couple with each other.
This c.m. subsystem can be solved exactly and provides magneto- phonon like
collective excitations. The inter-dot interaction is involved only through a
single interaction parameter. The relative coordinates of individual dots form
decoupled subsystems giving rise to intra-dot excitations. As an example, the
latter are calculated exactly for two-electron dots.
  Emphasis is layed on qualitative effects like: i) Influence of the magnetic
field on the lattice instability due to inter-dot interaction, ii) Closing of
the gap between the lower and the upper c.m. mode at B=0 for elliptical dots
due to dot interaction, and iii) Kinks in the single dot excitation energies
(versus magnetic field) due to change of ground state angular momentum. It is
shown that for obtaining striking qualitative effects one should go beyond
simple cubic lattices with spherical dots. We also prove a more general version
of the Kohn Theorem for quantum dot lattices. It is shown that for observing
effects of electron- electron interaction between the dots in FIR spectra
(breaking Kohn's Theorem) one has to consider dot lattices with at least two
dot species with different confinement tensors.

</DOC>
<DOC>
<DOCNO> 69346 </DOCNO>
Meson decay in an independent quark model


  Leptonic decay widths and leptonic decay constants of light vector mesons and
weak leptonic decay widths and weak decay constants of light and heavy
pseudoscalar mesons have been studied in a field- theoretic framework based on
the independent quark model with a scalar- vector power-law potential. The
results are in very good agreement with the experimental data.

</DOC>
<DOC>
<DOCNO> 83243 </DOCNO>
Approximation and Exactness in Finite State Optimality Theory


  Previous work (Frank and Satta 1998; Karttunen, 1998) has shown that
Optimality Theory with gradient constraints generally is not finite state. A
new finite-state treatment of gradient constraints is presented which improves
upon the approximation of Karttunen (1998). The method turns out to be exact,
and very compact, for the syllabification analysis of Prince and Smolensky
(1993).

</DOC>
<DOC>
<DOCNO> 178584 </DOCNO>
Generator coordinate method calculations of one-nucleon removal


  An approach to the Generator Coordinate Method (GCM) using Skyrme-type
effective forces and Woods-Saxon construction potential is applied to calculate
the single-particle proton and neutron overlap functions in $^{40}$Ca. The
relationship between the bound-state overlap functions and the one-body density
matrix has been used. These overlap functions are applied to calculate the
cross sections of one-nucleon removal reactions such as ($e,e'p$), ($\gamma,p$)
and ($p,d$) on $^{40}$Ca on the same theoretical footing. A consistent
description of data for the different reactions is achieved. The shapes of the
experimental cross sections for transitions to the $3/2^{+}$ ground state and
the first $1/2^{+}$ excited state of the residual nuclei are well reproduced by
the overlap functions obtained within the GCM. An additional spectroscopic
factor accounting for correlations not included in the overlap function must be
applied to the calculated results to reproduce the size of the experimental
cross sections.

</DOC>
<DOC>
<DOCNO> 68824 </DOCNO>
Monopoles and the Emergence of Black Hole Entropy


  One of the remarkable features of black holes is that they possess a
thermodynamic description, even though they do not appear to be statistical
systems. We use self-gravitating magnetic monopole solutions as tools for
understanding the emergence of this description as one goes from an ordinary
spacetime to one containing a black hole. We describe how causally distinct
regions emerge as a monopole solution develops a horizon. We define an entropy
that is naturally associated with these regions and that has a clear connection
with the Hawking-Bekenstein entropy in the critical black hole limit.

</DOC>
<DOC>
<DOCNO> 85507 </DOCNO>
General (Anti-)de Sitter Black Holes in Five Dimensions


  We find a general class of rotating charged black hole solutions to N=2, D=5
gauged supergravity coupled to vector supermultiplets. The supersymmetry
properties of these solutions are studied, and their mass and angular momenta
are obtained. We also compute the stress tensor of the dual D=4, N=4 super
Yang-Mills theory in the limit of strong `t Hooft coupling. It is shown that
closed timelike curves occur outside the horizon, indicating loss of unitarity
in the dual CFT. For imaginary coupling constant of the gravitini to the gauge
fields, one can obtain multi-centered rotating charged de Sitter black holes.
Some physical properties of these solutions are also discussed.

</DOC>
<DOC>
<DOCNO> 178960 </DOCNO>
The beta-beta two neutrino decay in 48Ca


  A schematic study of the $\beta \beta 2\nu $-decay of $^{48}Ca$ is made in a
shell-model approach. The emphasis is especially put on the role of the
spin-orbit potential in relation with the contribution of other terms in the
strong interaction. This is discussed with a particular attention to the
behavior of these ones under the SU(4) symmetry. Different methods in
calculating the transition amplitude are also looked at with the aim to
determine their reliability and, eventually, why they don't work. Further
aspects relative to the failure of the Operator Expansion Method to reproduce
the results of more elaborate calculations are examined.

</DOC>
<DOC>
<DOCNO> 40531 </DOCNO>
Diffractive Vector Meson Production at HERA


  The H1 and ZEUS collaborations at HERA report new data on the diffractive
production of vector mesons with a many-fold increase of luminosity compared to
previous measurements. The new data include photoproduction and
electroproduction of $\rho^0,\phi,J/\psi$. The available data on elastic VM
production indicate that the interaction scales as $Q^2+M_{V}^2$.

</DOC>
<DOC>
<DOCNO> 117079 </DOCNO>
Relativistic Geometry and Quantum Electrodynamics


  Excitations of a relativistic geometry are used to represent the theory of
quantum electrodynamics. The connection excitations and the frame excitations
reduce, respectively, to the electromagnetic field operator and electron field
operator. Because of the inherent geometric algebraic structure these operators
obey the standard commutation rules of QED. If we work with excitations, we
need to use statistical theory when considering the evolution of microscopic
subsystems. The use of classical statistics, in particular techniques of
irreversible thermodynamics, determine that the probability of absorption or
emission of a geometric excitation is a function of the classical energy
density. Emission and absorption of geometric excitations imply discrete
changes of certain physical variables, but with a probability determined by its
wave energy density. Hence, this geometric theory, without contradicting the
fundamental aspects of quantum physics, provides a geometric foundation for the
theory.

</DOC>
<DOC>
<DOCNO> 80983 </DOCNO>
Lattice supersymmetry with domain wall fermions


  Supersymmetry, like Poincare symmetry, is softly broken at finite lattice
spacing provided the gaugino mass term is strongly suppressed. Domain wall
fermions provide the mechanism for suppressing this term by approximately
imposing chiral symmetry on the lattice. We present the first numerical
simulations of N=1 supersymmetric SU(2) Yang-Mills on the lattice in d=4
dimensions using domain wall fermions.

</DOC>
<DOC>
<DOCNO> 13816 </DOCNO>
Numerically improved computational scheme for the optical conductivity


  The contour integration technique applied to calculate the optical
conductivity tensor at finite temperatures in the case of layered systems
within the framework of the spin-polarized relativistic screened
Korringa-Kohn-Rostoker band structure method is improved from the computational
point of view by applying the Gauss-Konrod quadrature for the integrals along
the different parts of the contour and by designing a cumulative special points
scheme for two-dimensional Brillouin zone integrals corresponding to cubic
systems.

</DOC>
<DOC>
<DOCNO> 151695 </DOCNO>
Polyakov's spin factor and new algorithms for efficient perturbative


  Polyakov's spin factor enters as a weight in the path-integral description of
particle-like modes propagating in Euclidean space-times, accounting for
particle spin. The Fock-Feynman-Schwinger path integral applied to QCD
accomodates Polyakov's spin factor in a natural manner while, at the same time,
it identifies Wilson line (loop) operators as sole agents of interaction
dynamics among matter and gauge field quanta. A direct application of such a
separation between spin content and dynamics is the emergence of master
expressions for the perturbative series involving either open or closed
fermionic lines which provide new, comprehensive approaches to perturbative
QCD.

</DOC>
<DOC>
<DOCNO> 84768 </DOCNO>
Black Holes in Non-flat Backgrounds: the Schwarzschild Black Hole in the


  As an example of a black hole in a non-flat background a composite static
spacetime is constructed. It comprises a vacuum Schwarzschild spacetime for the
interior of the black hole across whose horizon it is matched on to the
spacetime of Vaidya representing a black hole in the background of the Einstein
universe. The scale length of the exterior sets a maximum to the black hole
mass. To obtain a non-singular exterior, the Vaidya metric is matched to an
Einstein universe. The behaviour of scalar waves is studied in this composite
model.

</DOC>
<DOC>
<DOCNO> 12755 </DOCNO>
Transport across a normal-superconducting interface: a novel probe of


  In this letter, we examine the effect of Coulomb interactions in the normal
region of a normal-superconducting (N/S) mesoscopic structure, here the change
from an attractive to a repulsive coulombic interaction, at the N/S interface,
causes a shift in the order parameter phase. We show that this shift has a
pronounced effect on Andreev bound states and demonstrate that the effect on
Andreev scattering of non-zero order-parameter tails, can be used to probe the
sign of the interaction in the normal region.

</DOC>
<DOC>
<DOCNO> 84751 </DOCNO>
Can the Unruh-DeWitt detector extract energy from the vacuum?


  The Unruh effect can be correctly treated only by using the Minkowski
quantization and a model of a "particle" detector, not by using the Rindler
quantization. The energy produced by a detector accelerated only for a short
time can be much larger than the energy needed to change the velocity of the
detector. Although the measuring process lasts an infinite time, the production
of the energy can be qualitatively explained by a time-energy uncertainty
relation.

</DOC>
<DOC>
<DOCNO> 10912 </DOCNO>
Electron-electron interactions in graphene sheets


  The effects of the electron-electron interactions in a graphene layer are
investigated. It is shown that short range couplings are irrelevant, and scale
towards zero at low energies, due to the vanishing of density of states at the
Fermi level. Topological disorder enhances the density of states, and can lead
to instabilities. In the presence of sufficiently strong repulsive
interactions, p-wave superconductivity can emerge.

</DOC>
<DOC>
<DOCNO> 152065 </DOCNO>
Tachyon Condensation on Noncommutative Torus


  We discuss noncommutative solitons on a noncommutative torus and their
application to tachyon condensation. In the large B limit, they can be exactly
described by the Powers-Rieffel projection operators known in the mathematical
literature. The resulting soliton spectrum is consistent with T-duality and is
surprisingly interesting. It is shown that an instability arises for any
D-branes, leading to the decay into many smaller D-branes. This phenomenon is
the consequence of the fact that K-homology for type II von Neumann factor is
labeled by R.

</DOC>
<DOC>
<DOCNO> 71680 </DOCNO>
The light scalars, especially the sigma, in charm decay and elsewhere


  We discuss how the lightest scalars, in particular the broad sigma resonance,
can be understood as unitarized (qbar q) states within a unitarized quark model
(UQM). The bare (qbar q) scalars are strongly distorted by hadronic mass
shifts, and the (ubar u+ dbar d) state becomes a very broad resonance, with its
pole at 470-i250 MeV. This is the sigma meson required by models for
spontaneous breaking of chiral symmetry. We also discuss the less well known
phenomenon that with a large coupling there can appear two physical resonance
poles on the second sheet although only one bare quark-antiquark state is put
in. The f_0(980) and f_0(1370) resonance poles can thus be two manifestations
of the same (sbar s) quark state. Both of these are dominant in the E791 Dalitz
plot of D_s-> 3pi, where (sbar s) intermediate states should be dominant.
Recently this light sigma has clearly been observed in D-> sigma pi-> 3pi by
the E791 experiment at Fermilab. We discuss how this decay channel can be
predicted in a Constituent Quark Meson Model (CQM), which incorporates heavy
quark and chiral symmetries.

</DOC>
<DOC>
<DOCNO> 121331 </DOCNO>
The X-ray Properties of Low-Frequency Quasi-Periodic Oscillations from


  We present a study of the properties of strong 0.8-3.0 Hz quasi-periodic
oscillations (QPOs) that occurred during 1997 RXTE observations of the
microquasar GRS 1915+105 in the low-hard state. The high count rates allow us
to track individual QPO peaks, and we exploit this to develop a QPO folding
technique. In contrast to previous QPO studies with RXTE, we emphasize the high
energy QPO properties and report the detection of a QPO in the 60-124 keV
energy band. Our technique allows us, for the first time, to measure the phase
of the QPO harmonics relative to the fundamental. Variation in this phase
difference leads to changes in the shape of the QPO profile with energy and
over time. The strength of the QPO fundamental increases up to 19 keV, but the
data do not suggest that the strength continues to increase above this energy.
In some cases, the QPO amplitudes in the 30-60 keV and 60-124 keV energy bands
are significantly less than in the 13-19 keV and 19-29 keV energy bands. We
also use our technique to measure the phase lag of the QPO fundamental and
harmonics. In the case where negative phase lags are detected for the
fundamental, positive phase lags are detected for the first harmonic.

</DOC>
<DOC>
<DOCNO> 118245 </DOCNO>
The afterglows of gamma-ray bursts


  Gamma-ray burst astronomy has undergone a revolution in the last three years,
spurred by the discovery of fading long-wavelength counterparts. We now know
that at least the long duration GRBs lie at cosmological distances with
estimated electromagnetic energy release of 10**51 -- 10**53 erg, making these
the brightest explosions in the Universe. In this article we review the current
observational state, beginning with the statistics of X-ray, optical, and radio
afterglow detections. We then discuss the insights these observations have
given to the progenitor population, the energetics of the GRB events, and the
physics of the afterglow emission. We focus particular attention on the
evidence linking GRBs to the explosion of massive stars. Throughout, we
identify remaining puzzles and uncertainties, and emphasize promising
observational tools for addressing them. The imminent launch of HETE-2 and the
increasingly sophisticated and coordinated ground-based and space-based
observations have primed this field for fantastic growth.

</DOC>
<DOC>
<DOCNO> 101724 </DOCNO>
Calculation of Thom polynomials for group actions


  Two effective theories are connected in the paper: the Vassiliev-Kazarian
theory of global singularities and the Szucs theory of generalied
Pontryagin-Thom construction.
  We give the correct definition and a way to compute the equivariant
cohomology classes-called generalized Thom polynomials-of orbits (strata) of a
group action. We show how this specializes to ordinary Thom polynomials of
singularities, and other examples.

</DOC>
<DOC>
<DOCNO> 118873 </DOCNO>
The Arecibo Dual-Beam Survey: Arecibo and VLA Observations


  The Arecibo Dual-Beam Survey is a "blind" 21 cm search for galaxies covering
\~430 deg^2 of sky. We present the data from the detection survey as well as
from the follow-up observations to confirm detections and improve positions and
flux measurements. We find 265 galaxies, many of which are extremely low
surface brightness. Some of these previously uncataloged galaxies lie within
the zone of avoidance where they are obscured by the gas and dust in our
Galaxy. 81 of these sources are not previously cataloged optically and there
are 11 galaxies that have no associated optical counterpart or are only
tentatively associated with faint wisps of nebulosity on the Digitized Sky
Survey images. We discuss the properties of the survey and in particular we
make direct determinations of the completeness and reliability of the sample.
The behavior of the completeness and its dependencies is essential for
determining the HI mass function. We leave the discussion of the mass function
for a later paper, but do note that we find many low surface brightness
galaxies and 7 sources with M_HI < 10^8 Msolar.

</DOC>
<DOC>
<DOCNO> 10689 </DOCNO>
Vicious walkers, friendly walkers and Young tableaux II: With a wall


  We derive new results for the number of star and watermelon configurations of
vicious walkers in the presence of an impenetrable wall by showing that these
follow from standard results in the theory of Young tableaux, and combinatorial
descriptions of symmetric functions. For the problem of $n$-friendly walkers,
we derive exact asymptotics for the number of stars and watermelons both in the
absence of a wall and in the presence of a wall.

</DOC>
<DOC>
<DOCNO> 121516 </DOCNO>
Hard X-rays from Type II bursts of the Rapid Burster and its transition


  We report on 4 BeppoSAX Target Of Opportunity observations of MXB 1730-335,
the Rapid Burster (RB), made during the 1998 February-March outburst. In the
first observation, approximately 20 days after the outburst peak, the X-ray
light curve showed Type II bursts at a rate of 43 per hour. Nine days later,
during the second BeppoSAX pointing, only 5 Type II bursts were detected at the
beginning of the observation. During the third pointing no X-ray bursts were
detected and in the fourth and final observation the RB was not detected at
all. Persistent emission from the RB was detected up to 10 keV during the first
three pointings. The spectra of the persistent and bursting emissions below 10
keV were best fit with a model consisting of two blackbodies. An additional
component (a power law) was needed to describe the 1-100 keV bursting spectrum
when the persistent emission was subtracted. To our knowledge, this is the
first detection of the RB beyond 20 keV. We discuss the evolution of the
spectral parameters for the bursting and persistent emission during the
outburst decay. The light curve, after the second BeppoSAX pointing, showed a
steepening of the previous decay trend, and a sharper decay rate leading to
quiescence was observed with BeppoSAX in the two subsequent observations. We
interpret this behaviour as caused by the onset of the propeller effect.
Finally, we infer a neutron star magnetic field B ~ 4 10^8 Gauss.

</DOC>
<DOC>
<DOCNO> 11627 </DOCNO>
Combined effect of frustration and dimerization in ferrimagnetic chains


  Within the zero-temperature linear spin-wave theory we have investigated the
effect of frustration and dimerization of a Heisenberg system with alternating
spins $s_{1}$ and $s_{2}$ on one- and two-dimensional lattices. The combined
effect most visibly appears in the elementary excitation spectra. In contrast
to the ground state energy that decreases with dimerization and increases with
frustration, the excitation energies are shown to be suppressed in energy by
both dimerization and frustration. The threshold value of frustration that
signals a transition from a classical ferrimagnetic state to a spiral state,
decreases with dimerization, showing that dimerization further helps in the
phase transition. The correlation length and sublattice magnetization decrease
with both dimerization and frustration indicating the destruction of the
long-range classical ferrimagnetic. The linear spin wave theory shows that in
the case of a square lattice, dimerization initially opposes the
frustration-led transition to a spiral magnetic state, but then higher
magnitudes of lattice deformation facilitate the transition. It also shows that
the transition to spiral state is inhibited in a square lattice beyond a
certain value of dimerization.

</DOC>
<DOC>
<DOCNO> 152514 </DOCNO>
AdS/CFT in the Infinite Momentum Frame


  This paper considers the spacetimes describing pp-waves propagating on
extremal non-dilatonic branes. It is shown that an observer moving along a
geodesic will experience infinite curvature at the horizon of the brane, which
should therefore be regarded as singular. Taking the decoupling limit of these
brane-wave spacetimes gives a pp-wave in AdS, the simplest example being the
Kaigorodov spacetime. It has been conjectured that gravity in this spacetime is
dual to a CFT in the infinite momentum frame with constant momentum density. If
correct, this implies that the CFT must resolve the singularity of the bulk
spacetime. Evidence in favour of this conjecture is presented. The unbroken
conformal symmetries determine the scalar 2-point function up to an arbitrary
function of one variable. However, an AdS/CFT calculation shows that this
function is constant (to leading order in $1/N^2$) and the result is therefore
the same as when the full conformal symmetry is unbroken. This paper also
discusses a recently discovered Virasoro symmetry of metrics describing
pp-waves in AdS and naked singularities in the Randall-Sundrum scenario.

</DOC>
<DOC>
<DOCNO> 11478 </DOCNO>
The Zeno effect and an inter-layer pairing mechanism for


  Quantum Zeno Effect (QZE) is the suppression of the inter-subspace transition
by a relatively fast intra-subspace decoherence. Earlier, we had proposed a
QZE-based mechanism for the temperature-dependent normal-state c-axis
resistivity of the layered high-T$_c$ cuprate superconductors in which the
single-particle inter-layer tunneling is blocked by the strong intra-layer
decoherence (entanglement). We now argue that while the single-particle
inter-layer tunneling is thus blocked, the tunneling of the bosonic BCS-like
pairs must remain unblocked inasmuch as a BCS pairing condensate is an
eigenstate of the pair annihilation operator. This pair tunneling stabilizes

</DOC>
<DOC>
<DOCNO> 116686 </DOCNO>
Semiclassical Dynamics of the Jaynes-Cummings Model


  The semiclassical approximation of coherent state path integrals is employed
to study the dynamics of the Jaynes-Cummings model. Decomposing the Hilbert
space into subspaces of given excitation quanta above the ground state, the
semiclassical propagator is shown to describe the exact quantum dynamics of the
model. We also present a semiclassical approximation that does not exploit the
special properties of the Jaynes-Cummings Hamiltonian and can be extended to
more general situations. In this approach the contribution of the dominant
semiclassical paths and the relevant fluctuations about them are evaluated.
This theory leads to an accurate description of spontaneous emission going
beyond the usual classical field approximation.

</DOC>
<DOC>
<DOCNO> 122904 </DOCNO>
Light Curves and Spectra of Dust Echoes From Gamma-Ray Bursts and their


  The relative brightening and reddening of the optical afterglows of GRB
970228 and GRB 980326 around 20 - 30 days after these bursts have been
attributed to supernovae, which are red (blueward of their spectral peak), and
which peak in time after about 20(1+z) days. However, this direct evidence for
a GRB/SN connection has recently been challenged. It has been suggested that
the late afterglows of these bursts can be explained by dust echoes, of which
we consider two cases: (1) the scattering of light from the afterglow (the
forward shock), the optical flash (the reverse shock), and/or optical light
from the burst itself by a shell of dust at a radius R from the progenitor, and
(2) the absorption and thermal re-emission of this light by this shell of dust.
In this paper, we model and compute dust echo light curves and spectra for both
cases. Although the late-time afterglow of GRB 980326 was not sufficiently well
sampled to rule out a dust echo description, we find that the late-time
afterglow of GRB 970228 cannot be explained by a dust echo.

</DOC>
<DOC>
<DOCNO> 7626 </DOCNO>
Superconducting gap anisotropy within the framework of a simple exchange


  The oxygen O2p_sigma and copper Cu4s and Cu3d_x^2-y^2 orbitals are involved
in a simple LCAO model for determination of the conduction band and the
oxygen-oxygen hopping is considered as a small parameter with respect to the
transition amplitude between nearest neighbours. The traditional Cooper pairing
is obtained by taking into account the double-electron exchange between the
nearest neighbours within the two-dimensional CuO_2 plane. The equation for the
superconducting gap is obtained as a result of the standard BCS treatment. It
is shown that the order parameter could have either s-type or d-type symmetry
depending on the ratio between the transition amplitudes. This model allows
understanding the experiments reporting a pi-shift of the Josephson phase
indicative for a d-type gap symmetry as well as the observed s-type in the case
of strongly irradiated samples.

</DOC>
<DOC>
<DOCNO> 121367 </DOCNO>
Lensing Sunyaev-Zel'dovich Clusters


  Full-sky microwave surveys like the upcoming Planck satellite mission will
detect of order 10^4 galaxy clusters through their thermal Sunyaev-Zel'dovich
effect. I investigate the properties of the gravitationally lensing subsample
of these clusters. The main results are: (1) The combined sample comprises
>~70% of the complete sample. (2) It is confined to redshifts 0.2+-0.1, and to
masses (5+-3) x 10^14 solar masses. (3) Using a particular measure for the weak
lensing effect, viz. the aperture mass, cluster masses can be determined with a
relative accuracy of ~20% if their density profile is known. Consequently, the
mass function of the combined sample can accurately be measured. (4) For
low-density universes, I predict a sharp peak in the measured (aperture) mass
function near 5 x 10^14 solar masses and explain its origin, showing that the
peak will be absent in high-density universes. (5) The location of the peak and
the exponential decrease of the mass function on its high-mass side will allow
the determination of the amplitude of the dark-matter power spectrum on the
cluster scale and the baryon fraction in clusters, and constrain the thermal
history of the intracluster gas.

</DOC>
<DOC>
<DOCNO> 118230 </DOCNO>
Effect of Reionization on the Structure Formation in the Universe


  I use simulations of cosmological reionization to quantify the effect of
photoionization on the gas fraction in low mass objects, in particular the
characteristic mass scale below which the gas fraction is reduced compared to
the universal value. I show that this characteristic scale can be up to an
order of magnitude lower than the linear theory Jeans mass, and that even if
one defines the Jeans mass at a higher overdensity, it does not track the
evolution of this characteristic suppression mass. Instead, the filtering mass,
which corresponds directly to the scale over which baryonic perturbations are
smoothed in linear perturbation theory, provides a remarkably good fit to the
characteristic mass scale. Thus, it appears that the effect of reionization on
structure formation in both the linear and nonlinear regimes is described by a
single characteristic scale, the filtering scale of baryonic perturbations. In
contrast to the Jeans mass, the filtering mass depends on the full thermal
history of the gas instead of the instantaneous value of the sound speed, so it
accounts for the finite time required for pressure to influence the gas
distribution in the expanding universe. In addition to the characteristic
suppression mass, I study the full shape of the probability distribution to
find an object with a given gas mass among all the objects with the same total
mass, and I show that the numerical results can be described by a simple
fitting formula that again depends only on the filtering mass. This simple
description of the probability distribution may be useful for semi-analytical
modeling of structure formation in the early universe.

</DOC>
<DOC>
<DOCNO> 68951 </DOCNO>
Gamma-Ray Bursts


  Ultra-high-energy, >10^19 eV, cosmic-ray and high energy, ~10^14 eV, neutrino
production in GRBs is discussed in the light of recent GRB and cosmic-ray
observations. Emphasis is put on model predictions that can be tested with
operating and planned cosmic-ray and neutrino detectors, and on the prospects
of testing for neutrino properties.

</DOC>
<DOC>
<DOCNO> 7774 </DOCNO>
Yang-Lee Theory for a Nonequilibrium Phase Transition


  To analyze phase transitions in a nonequilibrium system we study its grand
canonical partition function as a function of complex fugacity. Real and
positive roots of the partition function mark phase transitions. This behavior,
first found by Yang and Lee under general conditions for equilibrium systems,
can also be applied to nonequilibrium phase transitions. We consider a
one-dimensional diffusion model with periodic boundary conditions. Depending on
the diffusion rates, we find real and positive roots and can distinguish two
regions of analyticity, which can identified with two different phases. In a
region of the parameter space both of these phases coexist. The condensation
point can be computed with high accuracy.

</DOC>
<DOC>
<DOCNO> 169880 </DOCNO>
How behavior of systems with sparse spectrum can be predicted on a


  Call a spectrum of Hamiltonian sparse if each eigenvalue can be quickly
restored with accuracy $\epsilon$ from its rough approximation in within
$\epsilon_1$ by means of some classical algorithm. It is shown how a behavior
of system with sparse spectrum up to time $T=\frac{1-\rho}{14\epsilon}$ can be
predicted with fidelity $\rho$ on quantum computer in time
$t=\frac{4}{(1-\rho)\epsilon_1}$ plus the time of classical algorithm. The
quantum knowledge of Hamiltonian $H$ eigenvalues is considered as a wizard
Hamiltonian $W_H$ which action on any eigenvector of $H$ gives the
corresponding eigenvalue. Speedup of evolution for systems with sparse spectrum
is possible because for such systems wizard Hamiltonians can be quickly
simulated on a quantum computer. This simulation, generalizing Shor trick, is a
part of presented algorithm.
  In general case the action of wizard Hamiltonian cannot be simulated in time
smaller than the dimension of main space which is exponential of the size of
quantum system. For an arbitrary system (even for classical) its behavior
cannot be predicted on quantum computer even for one step ahead. This method
can be used also for restoration of a state of an arbitrary primary system in
time instant $-T$ in the past with the same fidelity which requires the same
time.

</DOC>
<DOC>
<DOCNO> 117578 </DOCNO>
Dynamics of the X-ray clusters Abell 222, Abell 223 and Abell 520


  We present the results of a dynamical analysis of three rich, X-ray luminous
galaxy clusters, Abell 222, Abell 223 and Abell 520, that are at intermediate
redshifts. Our study is based on radial velocities for 71 cluster members,
respectively 30 for A222, 20 for A223 and 21 for A520, measured from spectra
obtained at the Canada-France-Hawaii Telescope, the European Southern
Observatory, and the Pic du Midi Observatory, and supplemented with radial
velocities from the literature. A222 galaxies have slightly higher velocities
than those of A223, with bi-weighted mean velocity of V_{bi} = 64242 +/- 194
km/s for A222, and of V_{bi} = 63197 +/- 266 km/s for A223. The velocity
dispersions of the two clusters are about the same: sigma_{bi} = 1013 +/- 150
km/s and sigma_{bi} = 1058 +/- 160 km/s for A222 and A223, respectively. For
A520 we obtain V_{bi} = 60127 +/- 284 km/s with sigma_{bi} = 1250 +/- 189 km/s.
We also give mass and mass-luminosities ratio estimates for each cluster
separately. We argue that these clusters are presently undergoing strong
dynamical evolution and that A222 and A223 will probably merge in the future.
We have applied a Principal Component Analysis to a sample of 51 CFHT spectra
to produce a spectral classification for these galaxies. This classification
has allowed us to show that the morphological and kinematical segregations were
already established in these intermediate redshift clusters.

</DOC>
<DOC>
<DOCNO> 120002 </DOCNO>
SISSA Searching for blazars: the BLEIS project


  We present the aim and the status of the BLEIS project currently under
development at SISSA. This project consists in selecting a complete Blazar
sample from deep optical data, down to B=24.6, V=24.4 and I=23.7 (80%
completness). The optical images are taken from the ESO Imaging Survey (EIS -
Wide), a public survey covering ~16 deg2 of the Southern Emisphere. This new
Blazar sample, thanks to the different energy band of the selection and to the
faintness of EIS images, will be useful not only in understanding the physics
of such objects, but also in evolutive and cosmological studies. It will also
be a new test for the unified models of AGNs and will be helpful in making
predictions for future deep surveys.

</DOC>
<DOC>
<DOCNO> 13189 </DOCNO>
Non-homogeneous magnetic field induced magnetic edge states and their


  The spectrum of magnetic edge states and their transport properties in the
presence of a perpendicular non-homogeneous magnetic field in a quantum wire
formed by a parabolic confining potential are obtained. Systems are studied
where the magnetic field exhibits a discontinuous jump in the transverse
direction and changes its sign, strength, and both sign and strength at the
magnetic interface. The energy spectra and wave functions of these systems, the
corresponding group velocities along the interface and the particle average
positions normal to the interface are calculated. The resistance of the quantum
wire in the presence of such a magnetic interface is obtained both in the
ballistic and the diffusive regimes as a function of the Fermi energy and of
the homogeneous background magnetic field. The results are compared with those
for the case of a homogeneous field.

</DOC>
<DOC>
<DOCNO> 71310 </DOCNO>
A Possible Structure Model of the Vacuum: The Body Center Cubic Model of


  This paper has deduced the baryon spectrum using only 2 flavored quarks u and
d (each of them has three colored members). From Dirac's sea concept and the
quark confinement idea, we conjecture and then assume that the quarks (in the
vacuum state) compose colorless particles (uud and udd, hereafter will be
called the Lee Particles). Moreover, the Lee Particles lead in a natural way to
the construction - a body center cubic lattice in the vacuum. Consequently,
there exists a strong interaction periodic field with body center cubic
periodic symmetries and an electromagnetic interaction periodic field (from the
charged Lee Particles uud) with simple cubic periodic symmetries in the vacuum.
In terms of the energy band theory, using a point baryon approximation (i.e.,
omitting the structure of the Lee Particles), and from the symmetries of the
strong interaction periodic field, we have deduced the intrinsic quantum
numbers (I, S, C, b, Q) of all baryons and a unified mass formula from which
all baryon masses can be found. This theoretical baryon spectrum is in
accordance with the experimental results in both intrinsic quantum numbers and
masses. These results show that various baryons are the energy band excited
states of the Lee Particles. We also predict some new baryons: \Lambda
^0(2559), \Lambda ^0(4279), \Xi_C(3169), \Omega ^-(3619), \Lambda_C^+(6659),
\Lambda_b^0(10159) ... Furthermore, from the electromagnetic interaction
periodic field of the vacuum material, we predict a super heavy electron
spectrum E(166 Gev), E(332 Gev), E(498 Gev) ... We suggest that experiments to
find the super heavy electron spectrum and long lifetime baryon \Lambda
^0(2559) should be done.

</DOC>
<DOC>
<DOCNO> 102100 </DOCNO>
Approximation of dual Gabor frames, window decay, and wireless


  We consider three problems for Gabor frames that have recently received much
attention. The first problem concerns the approximation of dual Gabor frames in
$L_2(R)$ by finite-dimensional methods. Utilizing Wexler-Raz type duality
relations we derive a method to approximate the dual Gabor frame, that is much
simpler than previously proposed techniques. Furthermore it enables us to give
estimates for the approximation rate when the dimension of the finite model
approaches infinity. The second problem concerns the relation between the decay
of the window function $g$ and its dual $\gamma$. Based on results on
commutative Banach algebras and Laurent operators we derive a general condition
under which the dual $\gamma$ inherits the decay properties of $g$. The third
problem concerns the design of pulse shapes for orthogonal frequency division
multiplex (OFDM) systems for time- and frequency dispersive channels. In
particular, we provide a theoretical foundation for a recently proposed
algorithm to construct orthogonal transmission functions that are well
localized in the time-frequency plane.

</DOC>
<DOC>
<DOCNO> 70695 </DOCNO>
Testing LSND at long-baseline neutrino experiments


  Recently it was suggested that two very different mass-squared differences
play a role in atmospheric neutrino oscillations. The larger of these also
accounts for the LSND result and the smaller of these also drives the solar
neutrino oscillations. We consider the predictions of this scheme for
long-baseline experiments. We find that high statistics experiments, such as
MINOS, can observe a clean signal for this scheme, which is clearly
distinguishable from the usual scheme of atmospheric neutrino oscillations
driven by a single mass-squared difference.

</DOC>
<DOC>
<DOCNO> 68729 </DOCNO>
Neutrino conversions in cosmological gamma-ray burst fireballs


  We study neutrino conversions in a recently envisaged source of high-energy
neutrinos (E \geq 10^6 GeV), that is, in the vicinity of cosmological Gamma-Ray
Burst fireballs (GRB). We consider the effects of flavor and spin-flavor
conversions and point out that in both situations, a some what higher than
estimated high energy tau neutrino flux from GRBs is expected in new km^2
surface area under water/ice neutrino telescopes.

</DOC>
<DOC>
<DOCNO> 99606 </DOCNO>
Inverse Spectral Problem for Surfaces of Revolution


  This paper concerns the inverse spectral problem for analytic simple surfaces
of revolution. By `simple' is meant that there is precisely one critical
distance from the axis of revolution. Such surfaces have completely integrable
geodesic flows with global action-angle variables and possess global quantum
Birkhoff normal forms (Colin de Verdiere). We prove that isospectral surfaces
within this class are isometric. The first main step is to show that the normal
form at meridian geodesics is a spectral invariant. The second main step is to
show that the metric is determined from this normal form.

</DOC>
<DOC>
<DOCNO> 71014 </DOCNO>
Localized Gravity and Higher Curvature Terms


  We consider localization of gravity in smooth domain wall solutions of
gravity coupled to a scalar field with a generic potential in the presence of
the Gauss-Bonnet term. We discuss conditions on the scalar potential such that
domain wall solutions are non-singular. We point out that the presence of the
Gauss-Bonnet term does not allow flat solutions with localized gravity that
violate the weak energy condition. We also point out that in the presence of
the Gauss-Bonnet term infinite tension flat domain walls violate positivity. In
fact, for flat solutions unitarity requires that on the solution the scalar
potential be bounded below.

</DOC>
<DOC>
<DOCNO> 9399 </DOCNO>
Spin accumulation in the semi classical and quantum regimes


  We consider spin accumulation at a ferromagnet--normal metal interface in the
presence of magnetic scattering in the normal metal. In the classical regime,
we discuss the inverse Drude scaling of the conductance as a function of the
interface transparencies. We present a treatment based on an exact solution of
the Boltzmann equation. In the quantum regime, we solve a single impurity
``spin-flip Fabry Perot interferometer'' for quantum coherent multiple
scatterings, in which we find a resonance in the spin flip channels. This
resonance appears to be the quantum analog of the semi classical inverse Drude
scaling of the conductance.

</DOC>
<DOC>
<DOCNO> 99344 </DOCNO>
A braided simplicial group


  By studying braid group actions on Milnor's construction of the 1-sphere, we
show that the general higher homotopy group of the 3-sphere is the fixed set of
the pure braid group action on certain combinatorially described group. We also
give certain representation of higher differentials in the Adams spectral
sequence for the homotopy groups of the 2-sphere.

</DOC>
<DOC>
<DOCNO> 121092 </DOCNO>
Powerful jets from black hole X-ray binaries in Low/Hard X-ray states


  Four persistent (Cygnus X-1, GX 339-4, GRS 1758-258 and 1E 1740.7-2942) and
three transient (GS 2023+38, GRO J0422+32 and GS 1354-64) black hole X-ray
binary systems have been extensively observed at radio wavelengths during
extended periods in the Low/Hard X-ray state, which is characterised in X-rays
by a hard power-law spectrum and strong variability. All seven systems show a
persistent flat or inverted (in the sense that spectral index alpha >= 0) radio
spectrum in this state, markedly different from the optically thin radio
spectra exhibited by most X-ray transients within days of outburst.
Furthermore, in none of the systems is a high-frequency cut-off to this
spectral component detected, and there is evidence that it extends to
near-infrared or optical regimes. Luminous persistent hard X-ray states in the
black hole system GRS 1915+105 produce a comparable spectrum. This spectral
component is considered to arise in synchrotron emission from a conical,
partially self-absorbed jet, of the same genre as those originally considered
for Active Galactic Nuclei. Whatever the physical origin of the Low/Hard X-ray
states, these self-similar outflows are an ever-present feature. The power in
the jet component is likely to be a significant (> 5%) and approximately fixed
fraction of the total accretion luminosity. The correlation between hard X-ray
and synchrotron emission in all the sources implies that the jets are
intimately related to the Comptonisation process, and do not have very large
bulk Lorentz factors, unless the hard X-ray emission is also beamed by the same
factor.

</DOC>
<DOC>
<DOCNO> 101510 </DOCNO>
The Cohomology of the Sylow 2-subgroup of the Higman-Sims Group


  In this paper we compute the mod 2 cohomology of the Sylow 2-subgroup of the
Higman-Sims group HS, one of the 26 sporadic simple groups. We obtain its
Poincare series as well as an explicit description of it as a ring with 17
generators and 79 relations

</DOC>
<DOC>
<DOCNO> 72042 </DOCNO>
Simple solutions of fireball hydrodynamics for self-similar elliptic


  Simple, self-similar, elliptic solutions of non-relativistic fireball
hydrodynamics are presented, generalizing earlier results for spherically
symmetric fireballs with Hubble flows and homogeneous temperature profiles. The
transition from one dimensional to three dimensional expansions is investigated
in an efficient manner.

</DOC>
<DOC>
<DOCNO> 116518 </DOCNO>
A Comment on the Roe-Woodroofe Construction of Poisson Confidence


  We consider the Roe-Woodroofe construction of confidence intervals for the
case of a Poisson distributed variate where the mean is the sum of a known
background and an unknown non-negative signal. We point out that the intervals
do not have coverage in the usual sense but can be made to have such with a
modification that does not affect the believability and other desirable
features of this attractive construction. A similar modification can be used to
provide coverage to the construction recently proposed by Cousins for the
Gaussian-with-boundary problem.

</DOC>
<DOC>
<DOCNO> 68403 </DOCNO>
Unifying the Strengths of Forces in Higher Dimensions


  We consider the embedding of the Standard Model fields in a
$(4+d)$-dimensional theory while gravitons may propagate in $d'$ extra, compact
dimensions. We study the modification of strengths of the gravitational and
gauge interactions and, for various values of $d$ and $d'$, we determine the
energy scale at which these strengths are unified. Special cases where the
unification of strengths is characterized by the absence of any hierarchy
problem are also presented.

</DOC>
<DOC>
<DOCNO> 178598 </DOCNO>
Anharmonic properties of double giant dipole resonance


  A systematic microscopic study of the anharmonic properties of the double
giant dipole resonance (DGDR) has been carried out, for the first time, for
nuclei with mass number $A$ spanning the whole mass table. It is concluded that
the corrections of the energy centroid of the $J^{\pi} = 0^+$ and $2^+$
components of the DGDR from its harmonic limit are negative, have a value of
the order of few hundred keV and follow an $A^{-1}$ dependence.

</DOC>
<DOC>
<DOCNO> 150665 </DOCNO>
The Orbifolds of N=2 Superconformal Theories with c=3


  We construct Z_M, M= 2, 3, 4, 6 orbifold models of the N=2 superconformal
field theories with central charge c=3. Then we check the description of the
Z_3, Z_4 and Z_6 orbifolds by the N=2 superconformal Landau-Ginzburg models
with c=3, by comparing the spectrum of chiral fields, in particular the Witten
index Tr(-1)^F.

</DOC>
<DOC>
<DOCNO> 13292 </DOCNO>
Onset of antiferromagnetism in heavy fermion metals


  There are two views of antiferromagnets. The first proceeds from atomic
physics, which predicts that atoms with unpaired electrons develop magnetic
moments. In a solid, the coupling between moments on nearby ions then yields
antiferromagnetic order at low temperatures. The second, based on the physics
of electron fluids or 'Fermi liquids', states that Coulomb interactions can
drive the fluid to adopt a more stable configuration by developing a spin
density wave. It is presently unknown which view is appropriate at a `quantum
critical point', where the antiferromagnetic transition temperature vanishes.
Here we describe an atomically local contribution to the magnetic correlations
which develops in the metal CeCu$_{6-x}$Au$_{x}$ at the critical gold
concentration ($x_c=0.1$) where the magnetic ordering temperature is tuned to
zero. This contribution implies that a Fermi-liquid destroying spin-localizing
transition, unanticipated for the spin density wave description, coincides with
the antiferromagnetic quantum critical point.

</DOC>
<DOC>
<DOCNO> 84391 </DOCNO>
Hypothesis of path integral duality: Applications to QED


  We use the modified propagator for quantum field based on a ``principle of
path integral duality" proposed earlier in a paper by Padmanabhan to
investigate several results in QED. This procedure modifies the Feynman
propagator by the introduction of a fundamental length scale. We use this
modified propagator for the Dirac particles to evaluate the first order
radiative corrections in QED. We find that the extra factor of the modified
propagator acts like a regulator at the Planck scales thereby removing the
divergences that otherwise appear in the conventional radiative correction
calculations of QED. We find that:(i) all the three renormalisation factors
$Z_1$, $Z_2$, and $Z_3$ pick up finite corrections and (ii) the modified
propagator breaks the gauge invariance at a very small level of
${\mathcal{O}}(10^{-45})$. The implications of this result to generation of the
primordial seed magnetic fields are discussed.

</DOC>
<DOC>
<DOCNO> 80762 </DOCNO>
Instanton and Meron Physics in Lattice QCD


  Lattice field theory provides a quantitative tool to study the role of
nonperturbative semiclassical configurations in QCD. This talk briefly reviews
our present understanding of the role of instantons in QCD and describes in
detail new developments in the study of merons on the lattice.

</DOC>
<DOC>
<DOCNO> 8519 </DOCNO>
Phase-coherence time saturation in mesoscopic systems: wave function


  A finite phase-coherence time $\tau_{\phi}^{meas}$ emerges from iterative
measurement onto a quantum system. For a rapid sequence, the phase-coherence
time is found explicitly. For the stationary charge conduction problem, it is
bounded. At all order, in the time-interval of measurements, we propose a
general expression for $\tau_{\phi}^{meas}$.

</DOC>
<DOC>
<DOCNO> 8204 </DOCNO>
Collective Diffusion and a Random Energy Landscape


  Starting from a master equation in a quantum Hamiltonian form and a coupling
to a heat bath we derive an evolution equation for a collective hopping process
under the influence of a stochastic energy landscape. There results different
equations in case of an arbitrary occupation number per lattice site or in a
system under exclusion. Based on scaling arguments it will be demonstrated that
both systems belong below the critical dimension $d_c$ to the same universality
class leading to anomalous diffusion in the long time limit. The dynamical
exponent $z$ can be calculated by an $\epsilon = d_c-d$ expansion. Above the
critical dimension we discuss the differences in the diffusion constant for
sufficient high temperatures. For a random potential we find a higher mobility
for systems with exclusion.

</DOC>
<DOC>
<DOCNO> 11870 </DOCNO>
Theory of Ideal Four-Wave Mixing in Bose-Einstein Condensates


  Starting from a second-quantized Hamiltonian of many-particle systems, we
derive the Gross-Pitaevskii (GP) equation in momentum space, which is suitable
for studying the multi-wave mixing processes of coherent matter waves. The
coupling equations are then applied to study ideal four-wave mixing (4WM), in
which only four waves with definite wavevectors are involved. Some interesting
problems of 4WM, such as the phase-matching condition, the collapse and revival
behaviour, the effects of relative phase difference, and the conversion
efficiency are discussed in detail. We also show that the main characters of
recent 4WM experiment [Deng et al, Nature 398, 218 (1999)] can be undersood in
the present simplified model.

</DOC>
<DOC>
<DOCNO> 169604 </DOCNO>
Entangled SU(2) and SU(1,1) coherent states


  Entangled SU(2) and SU(1,1) coherent states are developed as superpositions
of multiparticle SU(2) and SU(1,1) coherent states. In certain cases, these are
coherent states with respect to generalized su(2) and su(1,1) generators, and
multiparticle parity states arise as a special case. As a special example of
entangled SU(2) coherent states, entangled binomial states are introduced and
these entangled binomial states enable the contraction from entangled SU(2)
coherent states to entangled harmonic oscillator coherent states. Entangled
SU(2) coherent states are discussed in the context of pairs of qubits. We also
introduce the entangled negative binomial states and entangled squeezed states
as examples of entangled SU(1,1) coherent states. A method for generating the
entangled SU(2) and SU(1,1) coherent states is discussed and degrees of
entanglement calculated. Two types of SU(1,1) coherent states are discussed in
each case: Perelomov coherent states and Barut-Girardello coherent states.

</DOC>
<DOC>
<DOCNO> 120997 </DOCNO>
Thermal X-ray Emission and Cosmic Ray Production in Young Supernova


  We have developed a simple model to investigate the modifications of the
hydrodynamics and non-equilibrium ionization X-ray emission in young supernova
remnants due to nonlinear particle acceleration. In nonlinear, diffusive shock
acceleration, the heating of the gas to X-ray emitting temperatures is strongly
coupled to the acceleration of cosmic ray ions. If the acceleration is
efficient and a significant fraction of the shock ram energy ends up in cosmic
rays, compression ratios will be higher and the shocked temperature lower than
test-particle, Rankine-Hugoniot relations predict. We illustrate how particle
acceleration impacts the interpretation of X-ray data using the X-ray spectra
of Kepler's remnant, observed by ASCA and RXTE. The thermal X-ray emission
provides important constraints on the efficiency of particle acceleration, in
complement to nonthermal emission. X-ray data from Chandra and XMM Newton, plus
radio observations, will be essential to quantify nonlinear effects.

</DOC>
<DOC>
<DOCNO> 169903 </DOCNO>
Quantum to Classical Transition from the Cosmic Background Radiation


  We have revisited the Ghirardi-Rimini-Weber-Pearle (GRWP) approach for
continuous dynamical evolution of the state vector for a macroscopic object.
Our main concern is to recover the decoupling of the state vector dynamics for
the center-of-mass (CM) and internal motion, as in the GRWP model, but within
the framework of the standard cosmology. In this connection we have taken the
opposite direction of the GRWP argument, that the cosmic background radiation
(CBR) has originated from a fundamental stochastic hitting process. We assume
the CBR as a clue of the Big Bang, playing a main role in the decoupling of the
state vector dynamics of the CM and internal motion. In our model, instead of
describing a continuous spontaneous localization (CSL) of a system of massive
particles as proposed by Ghirardi, Pearle and Rimini, the It\^{o} stochastic
equation accounts for the intervention of the CBR on the system of particles.
Essentially, this approach leads to a pre-master equation for both the CBR and
particles degrees of freedom. The violation of the principle of energy
conservation characteristic of the CSL model is avoided as well as the
additional assumption on the size of the GRWP's localization width necessary to
reach the decoupling between the collective and internal motions. Moreover,
realistic estimation for the decoherence time, exhibiting an interesting
dependence on the CBR temperature, is obtained. From the formula for the
decoherence time it is possible to analyze the transition from micro to macro
dynamics in both the early hot Universe and the nowadays cold one. The entropy
of the system under decoherence is analyzed and the emergent `pointer basis' is
discussed. In spite of not having imposed a privileged basis, in our model the
position still emerges as the preferred observable as in the CSL model.

</DOC>
<DOC>
<DOCNO> 8265 </DOCNO>
Sonoluminescence as a Physical Vacuum Excitation


  We are discussing Schwinger'idea that physical mechanism of sonoluminescence
is a physical vacuum excitation. This theory was based on the assumption that
the sudden change of the rate of bubble collapse leads to the jump of
dielectric constant of the gas trapped inside the bubble. We show that the
dependence of the dielectric constant on the gas density really leads to the
jump of the dielectric constant at shock-wave propagation in a collapsing gas
bubble.

</DOC>
<DOC>
<DOCNO> 69666 </DOCNO>
Report of the QCD Working Group


  The activities of the QCD working group concentrated on improving the
understanding and Monte Carlo simulation of multi-jet final states due to hard
QCD processes at LEP, i.e. quark-antiquark plus multi-gluon and/or secondary
quark production, with particular emphasis on four-jet final states and b-quark
mass effects. Specific topics covered are: relevant developments in the main
event generators PYTHIA, HERWIG and ARIADNE; the new multi-jet generator
APACIC++; description and tuning of inclusive (all-flavour) jet rates; quark
mass effects in the three- and four-jet rates; mass, higher-order and
hadronization effects in four-jet angular and shape distributions; b-quark
fragmentation and gluon splitting into b-quarks.

</DOC>
<DOC>
<DOCNO> 70728 </DOCNO>
Prolongation of Friction Dominated Evolution for Superconducting Cosmic


  This investigation is concerned with cosmological scenarios based on particle
physics theories that give rise to superconducting cosmic strings (whose
subsequent evolution may produce stable loop configurations known as vortons).
Cases in which electromagnetic coupling of the string current is absent or
unimportant have been dealt with in previous work. The purpose of the present
work is to provide quantitative estimates for cases in which electromagnetic
interaction with the surrounding plasma significantly affects the string
dynamics. In particular it will be shown that the current can become
sufficiently strong for the initial period of friction dominated string motion
to be substantially prolonged, which would entail a reinforcement of the short
length scale end of the spectrum of the string distribution, with potentially
observable cosmological implications if the friction dominated scenario lasts
until the time of plasma recombination.

</DOC>
<DOC>
<DOCNO> 85256 </DOCNO>
A List of References on Spacetime Splitting and Gravitoelectromagnetism


  Revised version to be published in the Proceedings of the Encuentros
Relativistas Espa\~noles, September, 2000 [ http://hades.eis.uva.es/EREs2000 ]

</DOC>
<DOC>
<DOCNO> 11048 </DOCNO>
Quasiparticle dispersion and lineshape in a strongly correlated liquid


  A model of a strongly correlated electron liquid based on the fermion
condensation (FC) is applied to the consideration of high temperature
superconductors in its superconducting and normal states. Within our model the
appearance of FC presents a boundary, separating the region of strongly
interacting electron liquid from the region of strongly correlated electron
liquid. We show that at temperatures $T<T_c$ the quasiparticle dispersion in
systems with FC can be presented by two straight lines, characterized by
effective masses $M^*_{FC}$ and $M^*_L$, respectively, and intersecting near
the binding energy which is of the order of the superconducting gap. This same
picture persists in the normal state being modified only by the presence of the
quasiparticle width. We argue that this strong change of the quasiparticle
dispersion can be enhanced in underdoped samples due to strengthening the FC
influence. The single particle excitation width and lineshape are also studied.

</DOC>
<DOC>
<DOCNO> 84549 </DOCNO>
An extreme critical space-time: echoing and black-hole perturbations


  A homothetic, static, spherically symmetric solution to the massless
Einstein- Klein-Gordon equations is described. There is a curvature singularity
which is central, null, bifurcate and marginally trapped. The space-time is
therefore extreme in the sense of lying at the threshold between black holes
and naked singularities, just avoiding both. A linear perturbation analysis
reveals two types of dominant mode. One breaks the continuous self-similarity
by periodic terms reminiscent of discrete self-similarity, with echoing period
within a few percent of the value observed numerically in near-critical
gravitational collapse. The other dominant mode explicitly produces a black
hole, white hole, eternally naked singularity or regular dispersal, the latter
indicating that the background is critical. The black hole is not static but
has constant area, the corresponding mass being linear in the perturbation
amplitudes, explicitly determining a unit critical exponent. It is argued that
a central null singularity may be a feature of critical gravitational collapse.

</DOC>
<DOC>
<DOCNO> 83375 </DOCNO>
Robust Classification for Imprecise Environments


  In real-world environments it usually is difficult to specify target
operating conditions precisely, for example, target misclassification costs.
This uncertainty makes building robust classification systems problematic. We
show that it is possible to build a hybrid classifier that will perform at
least as well as the best available classifier for any target conditions. In
some cases, the performance of the hybrid actually can surpass that of the best
known classifier. This robust performance extends across a wide variety of
comparison frameworks, including the optimization of metrics such as accuracy,
expected cost, lift, precision, recall, and workforce utilization. The hybrid
also is efficient to build, to store, and to update. The hybrid is based on a
method for the comparison of classifier performance that is robust to imprecise
class distributions and misclassification costs. The ROC convex hull (ROCCH)
method combines techniques from ROC analysis, decision analysis and
computational geometry, and adapts them to the particulars of analyzing learned
classifiers. The method is efficient and incremental, minimizes the management
of classifier performance data, and allows for clear visual comparisons and
sensitivity analyses. Finally, we point to empirical evidence that a robust
hybrid classifier indeed is needed for many real-world problems.

</DOC>
<DOC>
<DOCNO> 102648 </DOCNO>
A Dolbeault-type Double Complex on Quaternionic Manifolds


  It has long been known that differential forms on complex manifolds can be
decomposed under the action of the complex structure to give the Dolbeault
complex.
  This paper presents an analogous double complex for quaternionic manifolds
using the fact that the cotangent space is isomorphic to a quaternionic vector
space. This defines an action of the group Sp(1) of unit quaternions on the
cotangent space, which induces an action of Sp(1) on the space of k-forms. A
double complex is obtained by decomposing the k-forms into irreducible
representations of Sp(1), resulting in new 'quaternionic Dolbeault' operators
and cohomology groups.
  Links with previous work in quaternionic geometry, particularly the
differential complex of Salamon and the q-holomorphic functions of Joyce, are
demonstrated.

</DOC>
<DOC>
<DOCNO> 40095 </DOCNO>
Cosmic ray tests of the D0 preshower detector


  The D0 preshower detector consists of scintillator strips with embedded
wavelength-shifting fibers, and a readout using Visible Light Photon Counters.
The response to minimum ionizing particles has been tested with cosmic ray
muons. We report results on the gain calibration and light-yield distributions.
The spatial resolution is investigated taking into account the light sharing
between strips, the effects of multiple scattering and various systematic
uncertainties. The detection efficiency and noise contamination are also
investigated.

</DOC>
<DOC>
<DOCNO> 123179 </DOCNO>
The standstill luminosity in Z Cam systems


  We consider accretion discs in close binary systems. We show that heating of
a disc at the impact point of the accretion stream contributes significantly to
the local energy budget at its outer edge. As a result the thermal balance
relation between local accretion rate and surface density (the `S-curve')
changes; the critical mass transfer rate above which no dwarf nova outbursts
occur can be up to 40% smaller than without impact heating. Standstills in ZCam
systems thus occur at smaller mass transfer rates than otherwise expected, and
are rather fainter than the peak luminosity during the dwarf nova phase as a
result.

</DOC>
<DOC>
<DOCNO> 84688 </DOCNO>
Detection of Scalar Gravitational Waves


  In this talk I review recent progresses in the detection of scalar
gravitational waves. Furthermore, in the framework of the Jordan-Brans-Dicke
theory, I compute the signal to noise ratio for a resonant mass detector of
spherical shape and for binary sources and collapsing stars. Finally I compare
these results with those obtained from laser interferometers and from
Einsteinian gravity.

</DOC>
<DOC>
<DOCNO> 9502 </DOCNO>
The Exchange-correlation Hole of the Si Atom, A Quantum Monte Carlo


  We have studied the exchange-correlation hole and pair correlation function
in the valence shell of the ground-state of the Si atom, using accurate
Slater-Jastrow wavefunctions and the Variational Monte Carlo method. The
exchange-correlation hole shows a number of interesting features caused by the
open shell structure of Si, including a marked transition from efficient to
poor screening behavior as a test majority-spin electron is moved from the
center of a valence 3p orbital onto the axis perpendicular to the occupied 3p
orbitals. This behavior results from the dramatic difference in the exchange
hole in the two cases, which is partially compensated by a corresponding
anisotropy in the correlation hole. In addition we observe an anisotropic
change in the spin density induced by Coulomb correlation, reducing the spatial
overlap between the different spin-components of the density and contributing
to the anisotropy of the correlation hole. In contrast to the longer range
features, we find that the "on-top" correlation hole is well described by
linear density functional theory, for a large range of local density and
magnetization.

</DOC>
<DOC>
<DOCNO> 118807 </DOCNO>
CDM models with a steplike initial power spectrum


  We investigate the properties of clusters of galaxies in the $\Lambda$CDM
models with a steplike initial power spectrum. We examine the mass function,
the peculiar velocities and the power spectrum of clusters in models with
different values of the density parameter $\Omega_0$, the normalized Hubble
constant h and the spectral parameter p, which describes the shape of the
initial power spectrum. The results are compared with observations. We also
investigate the rms bulk velocity in the models, where the properties of
clusters are consistent with the observed data. We find that the power spectrum
of clusters is in good agreement with the observed power spectrum of the
Abell-ACO clusters, if the spectral parameter p is in the range p=0.6-0.8. The
power spectrum and the rms peculiar velocity of clusters are consistent with
observations only if $\Omega_0<0.4$. The $\Omega_0=0.3$ models are consistent
with the observed properties of clusters, if h=0.50-0.63. For h=0.65, we find
that $\Omega_0=0.20 -0.27$.

</DOC>
<DOC>
<DOCNO> 71632 </DOCNO>
Neutrino Physics with Small Extra Dimensions


  We study neutrino physics in the context of the localized gravity model with
non-factorizable metric proposed by Randall and Sundrum. Identifying the
right-handed neutrino with a bulk fermion zero mode, which can be localized on
the ``hidden'' 3-brane in the Randall--Sundrum model, we obtain naturally small
Dirac neutrino masses without invoking a see-saw mechanism. Our model predicts
a strong hierarchy of neutrino masses and generically large mixing angles.

</DOC>
<DOC>
<DOCNO> 10159 </DOCNO>
Scale Invariance in the Nonstationarity of Physiological Signals


  We introduce a segmentation algorithm to probe temporal organization of
heterogeneities in human heartbeat interval time series. We find that the
lengths of segments with different local values of heart rates follow a
power-law distribution. This scale-invariant structure is not a simple
consequence of the long-range correlations present in the data. We also find
that the differences in mean heart rates between consecutive segments display a
common functional form, but with different parameters for healthy individuals
and for patients with heart failure. This finding may provide information into
the way heart rate variability is reduced in cardiac disease.

</DOC>
<DOC>
<DOCNO> 40364 </DOCNO>
Search for Second and Third Generation Leptoquarks at CDF


  We report the results of a search for second and third generation leptoquarks
using 88 ${pb}^{-1}$ of data recorded by the Collider Detector at Fermilab.
Color triplet technipions, which play the role of scalar leptoquarks, are
investigated due to their potential production in decays of strongly coupled
color octet technirhos. Events with a signature of two heavy flavor jets and
missing energy may indicate the decay of a second (third) generation leptoquark
to a charm (bottom) quark and a neutrino. As the data is found to be consistent
with Standard Model expectations, mass limits are determined.

</DOC>
<DOC>
<DOCNO> 100578 </DOCNO>
Diffeomorphisms, symplectic forms, and Kodaira fibrations


  As was recently pointed out by McMullen and Taubes [Math. Res. Lett. 6 (1999)
681-696], there are 4-manifolds for which the diffeomorphism group does not act
transitively on the deformation classes of orientation-compatible symplectic
structures. This note points out some other 4-manifolds with this property
which arise as the orientation-reversed versions of certain complex surfaces
constructed by Kodaira [J. Analyse Math. 19 (1967) 207-215]. While this
construction is arguably simpler than that of McMullen and Taubes, its
simplicity comes at a price: the examples exhibited herein all have large
fundamental groups.

</DOC>
<DOC>
<DOCNO> 116936 </DOCNO>
An ECR hydrogen negative ion source at CEA/Saclay: preliminary results


  The development of a high intensity negative ion source is part of a
considerably larger activity presently undergoing at CEA Saclay in the field of
high intensity linear accelerators. Preliminary studies toward the construction
of a 2.45 GHz ECR H- ion source have been performed for few months. This new
test bench takes advantage of our experience on the French high intensity
proton source SILHI. In the new source, the high-energy electrons created in
the ECR zone are trapped by a dipole magnetic filter. A rectangular 200 mm long
plasma chamber and an intermediate iron shield are used to minimize the
magnetic field in the extraction region. A second magnetic filter separates
electrons and negative ions in a 10 kV extraction system. To reduce the
electron/H- ratio, the plasma electrode is slightly polarized. The design
allows future evolutions such as cesium injection, higher energy extraction and
plasma diagnostics. The installation of the source is now in progress. The
first helium plasma has been produced for few weeks to verify the electron
separator behavior. The design, computations and the first results of the
source are presented.

</DOC>
<DOC>
<DOCNO> 68580 </DOCNO>
R-parity violating anomaly mediated supersymmetry breaking


  We propose a new scenario that solves the slepton negative mass squared
problem of the minimal supersymmetric standard model with anomaly mediated
supersymmetry breaking. The solution is achieved by including three trilinear
R-parity violating operators in the superpotential. The soft supersymmetry
breaking terms satisfy renormalisation group invariant relations in terms of
supersymmetric couplings and the overall supersymmetry breaking mass scale.
Flavour changing neutral currents can be naturally highly suppressed. A
specific model predicts tan beta=4.2+/-1.0. Excluding sleptons, the
supersymmetric particle spectrum then depends upon two remaining free
parameters. In the case of the R-parity violating couplings set at their
quasi-fixed points at a supersymmetric GUT scale, the whole sparticle spectrum
approximately depends upon only one free parameter. Imposing experimental
limits leads to a constrained and distinctive phenomenology. The lightest
CP-even Higgs of mass m_h=118 GeV would be seen at the Tevatron. All sparticles
and heavy Higgs would evade detection except for the lightest charginos and
neutralinos, whose distinctive leptonic decays would be seen at the LHC.

</DOC>
<DOC>
<DOCNO> 150366 </DOCNO>
Heterotic/Type II Triality and Instantons on $K_3$


  A detailed understanding of instanton effects for half-BPS couplings is
pursued in theories with 16 supersymmetries. In particular, we investigate the
duality between heterotic string on $T^4$ and type IIA on $K_3$ at the
$T^4/Z_2$ orbifold point, as well as their higher and lower dimensional
versions. We present a remarkably clean quantitative test of the duality at the
level of $F^4$ couplings, by completely matching a purely one-loop heterotic
amplitude to a purely tree-level type II result. The triality of SO(4,4) and
several other miracles are shown to be crucial for the duality to hold. Exact
non-perturbative new results for type I', F on $K_3$, M on $K_3$, and IIB on
$K_3$ are found, and the general form of D-instanton contributions in type IIA
or B on $T^4/Z_2$ is obtained. We also analyze the NS5-brane contributions in
type II on $K_3\times T^2$, and predict the value $\mu (N)=\sum_{d|N} (1/d^3)$
for the bulk contribution to the index of the NS5-brane world-volume theory on
$K_3 \times T^2$.

</DOC>
<DOC>
<DOCNO> 10118 </DOCNO>
Complete determination of the reflection coefficient in neutron specular


  An experimental method is proposed which allows the complete determination of
the complex reflection coefficient for absorptive media for positive and
negative values of the momenta. It makes use of magnetic reference layers and
is a modification of a recently proposed technique for phase determination
based on polarization measurements. The complex reflection coefficient
resulting from a simulated application of the method is used for a
reconstruction of the scattering density profiles of absorptive non-magnetic
media by inversion.

</DOC>
<DOC>
<DOCNO> 100122 </DOCNO>
Shock capturing by anisotropic diffusion oscillation reduction


  This paper introduces the method of anisotropic diffusion oscillation
reduction (ADOR) for shock wave computations. The connection is made between
digital image processing,in particular, image edge detection, and numerical
shock capturing. Indeed, numerical shock capturing can be formulated on the
lines of iterative digital edge detection. Various anisotropic diffusion and
super diffusion operators originated from image edge detection are proposed for
the treatment of hyperbolic conservation laws and near-hyperbolic hydrodynamic
equations of change. The similarity between anisotropic diffusion and
artificial viscosity is discussed. Physical origins and mathematical properties
of the artificial viscosity is analyzed from the kinetic theory point of view.
A form of pressure tensor is derived from the first principles of the quantum
mechanics. Quantum kinetic theory is utilized to arrive at macroscopic
transport equations from the microscopic theory. Macroscopic symmetry is used
to simplify pressure tensor expressions. The latter provides a basis for the
design of artificial viscosity. The ADOR approach is validated by using
(inviscid) Burgers' equation in one and two spatial dimensions, the
incompressible Navier-Stokes equation and the Euler equation. A discrete
singular convolution (DSC) algorithm is utilized for the spatial
discretization.

</DOC>
<DOC>
<DOCNO> 117277 </DOCNO>
Compound Poisson Statistics and Models of Clustering of Radiation


  According to the experimental evidence damage induced by densely ionizing
radiation in mammalian cells is distributed along the DNA molecule in the form
of clusters. The most critical constituent of DNA damage are double-strand
breaks (DSBs) which are formed when the breaks occur in both DNA strands and
are directly opposite or separated by only a few base pairs. The paper
discusses a model of clustered DSB formation viewed in terms of compound
Poisson process along with the predictive assay of the formalism in application
to experimental data.

</DOC>
<DOC>
<DOCNO> 40459 </DOCNO>
The Standard Model: Physical Basis and Scattering Experiments


  We present an introduction into the basic concepts of the Standard Model,
i.e. the gauge theories of the forces and the Higgs mechanism for generating
masses. The Glashow-Salam-Weinberg theory of the electroweak interactions will
be described in detail. The key experiments are reviewed, including the
precision tests at high energies. Finally, the limitations and possible physics
areas beyond the Standard Model are discussed.

</DOC>
<DOC>
<DOCNO> 68250 </DOCNO>
String Universality


  If there is a single underlying "theory of everything" which in some limits
of its "moduli space" reduces to the five weakly coupled string theories in
10D, and 11D SUGRA, then it is possible that all six of them have some common
domain of validity and that they are in the same universality class, in the
sense that the 4D low energy physics of the different theories is the same. We
call this notion String Universality. This suggests that the true vacuum of
string theory is in a region of moduli space equally far (in some sense) from
all perturbative theories, most likely around the self-dual point with respect
to duality symmetries connecting them. We estimate stringy non-perturbative
effects from wrapped brane instantons in each perturbative theory, show how
they are related by dualities, and argue that they are likely to lead to moduli
stabilization only around the self-dual point. We argue that moduli
stabilization should occur near the string scale, and SUSY breaking should
occur at a much lower intermediate scale, and that it originates from different
sources. We discuss the problems of moduli stabilization and SUSY breaking in
currently popular scenarios, explain why these problems are generic, and
discuss how our scenario can evade them. We show that String Universality is
not inconsistent with phenomenology but that it is in conflict with some
popular versions of brane world scenarios.

</DOC>
<DOC>
<DOCNO> 99710 </DOCNO>
Longo-Rehren subfactors arising from $\alpha$-induction


  We study (dual) Longo-Rehren subfactors $M\otimes M^{opp} \subset R$ arising
from various systems of endomorphisms of M obtained from alpha-induction for
some braided subfactor $N\subset M$. Our analysis provides useful tools to
determine the systems of R-R morphisms associated with such Longo-Rehren
subfactors, which constitute the ``quantum double'' systems in an appropriate
sense. The key to our analysis is that alpha-induction produces half-braidings
in the sense of Izumi, so that his general theory can be applied. Nevertheless,
alpha-induced systems are in general not braided, and thus our results allow to
compute the quantum doubles of (certain) systems without braiding. We
illustrate our general results by several examples, including the computation
of the quantum double systems for the asymptotic inclusion of the E_8 subfactor
as well as its three analogues arising from conformal inclusions of SU(3)_k.

</DOC>
<DOC>
<DOCNO> 11869 </DOCNO>
Antiferromagnetic spin ladders effectively coupled by one-dimensional


  We study a model of the stripe state in strongly correlated systems
consisting of an array of antiferromagnetic spin ladders, each with $n_{leg}$
legs, coupled to each other through the spin-exchange interaction to charged
stripes in between each pair of ladders. The charged stripes are assumed to be
Luttinger liquids in a spin-gap regime (Luther-Emery). An effective interaction
for a pair of neighboring ladders is calculated by integrating out the gapped
spin degree of freedom in the charged stripe. The low energy effective theory
of each ladder is the usual nonlinear $\sigma$-model with additional cross
couplings of neighboring ladders. These interactions are found to favor either
in-phase or anti-phase short range spin orderings depending on whether the
charge stripe is site-centered or bond-centered as well as on its filling
factor and other physical parameters of the charged stripe.

</DOC>
<DOC>
<DOCNO> 117633 </DOCNO>
The 9.7 Micron Silicate Dust Absorption Toward the Cygnus A Nucleus and


  We report the detection of a 9.7 $\mu$m silicate dust absorption feature
toward the Cygnus A nucleus. Its optical depth is, however, significantly
smaller than that expected from the dust extinction toward the background
$L$-band emission region ($A_{\rm V}$ $\sim$ 150 mag). We argue that the most
likely explanation for the small optical depth is that the obscuring dust
exists so close to the central engine that a temperature gradient occurs. Our
calculation confirms that the small optical depth and the spectral energy
distribution at 3--30 $\mu$m can be quantitatively reproduced by this
explanation. Combining this picture with the huge AGN luminosity, the emission
properties of Cygnus A are consistent with those of a type 2 quasar, that is, a
highly luminous AGN that is highly obscured ($A_{\rm V}$ $>$ 50 mag) by a dusty
torus with an inner radius of $<$10 pc, and not by $>$ a few 100 pc scale dust
in the host galaxy.

</DOC>
<DOC>
<DOCNO> 7678 </DOCNO>
Thermodynamic and spectroscopic properties and low temperature


  Two narrow anomalies with peaks at $\sim 30 K$ and $\sim 60 K$ and a wide
diffuse anomaly within the range 110-240 K have been found in a low temperature
heat capacity of chromium tris-acetylacetonate Cr(AA)_3. Besides, the
reversible change in color has been discovered when cooling the crystals to
liquid nitrogen temperature (thermochromism). To clear up the nature of these
effects the static magnetic susceptibility was measured within the temperature
range 2-300 K, the ESR-spectra on the Cr^{3+} ion and the transmission spectra
in visible region were recorded at 78 K and 300 K, the Raman spectra were
measured within the range 5-220 K. It has been ascertained that the reversible
effect of thermochromism is observed in most of $\beta$-diketonates of the
transition metals. Some tentative considerations concerning the origin of
discovered effects are put forward.

</DOC>
<DOC>
<DOCNO> 150825 </DOCNO>
The Interplay Between $\theta$ and T


  We extend a recent computation of the dependence of the free energy, F, on
the noncommutative scale $\theta$ to theories with very different UV
sensitivity. The temperature dependence of $F$ strongly suggests that a reduced
number of degrees of freedom contributes to the free energy in the non-planar
sector, $F_{\rm np}$, at high temperature. This phenomenon seems generic,
independent of the UV sensitivity, and can be traced to modes whose thermal
wavelengths become smaller than the noncommutativity scale. The temperature
dependence of $F_{\rm np}$ can then be calculated at high temperature using
classical statistical mechanics, without encountering a UV catastrophe even in
large number of dimensions. This result is a telltale sign of the low number of
degrees of freedom contributing to $F$ in the non-planar sector at high
temperature. Such behavior is in marked contrast to what would happen in a
field theory with a random set of higher derivative interactions.

</DOC>
<DOC>
<DOCNO> 120873 </DOCNO>
CO band emission from MWC349: I. First overtone bands from a disk or


  We observed the near infrared emission in the wavelength range 2.28-2.50
micron from the peculiar B[e]-star MWC349. The spectra contain besides the
strong IR continuum the first overtone CO bands and most of the hydrogen
recombination lines of the Pfund series, both in emission. We also modeled the
spectra. The Pfund lines have a gaussian profile with a FWHM of ~100 km/s, and
it turned out that their emission is in LTE and optically thin. To explain the
CO bands, several scenarios were investigated. We found that the CO band heads
are formed under LTE and that the gas must have a temperature of 3500 to 4000
K. The width of the 2 -> 0 band head indicates kinematical broadening of 50 to
60 km/s. We can obtain fits to the measured spectra assuming that the CO gas
has a column density of 5 10^{20} cm^{-2} and is located either at the inner
edge of the rotating circumstellar disk. In this case, the disk must have a
bulge which partly blocks the radiation so that the observer sees only a sector
on the far side where the radial velocities are small. Or the CO emission
originates in a wind with gaussian line profiles. Both fits are of equal
quality and satisfactory. In a third alternative where the fit is less
convincing, the CO emission is optically thin and comes from an extended
Keplerian disk.

</DOC>
<DOC>
<DOCNO> 10730 </DOCNO>
Pseudogap and its influence on normal and superconducting states of


  A model incorporating simultaneous superconducting and lattice instabilities
has been studied in detail to estimate the nature of coupling and inter-play
between them. The phase diagram is obtained in the temperature-filling plane at
different values of the parameters of the model. It is found that a pseudogap
develops in the distorted phase that inhibits the appearance of the
superconducting transition. The superconducting instability is strongest for
the regime of filling where the van Hove singularity in the 2D density of
states is close to the chemical potential. The pseudogap, developed in the
distorted phase, is a function of temperature via the temperature dependence of
the distortion itself. Transport properties, namely resistivity and thermopower
are found to be strongly dependent on the variations of the pseudogap.

</DOC>
<DOC>
<DOCNO> 11094 </DOCNO>
Ferromagnetic ordering in a generalized Hubbard model: weak intra-atomic


  In the present work ferromagnetic ordering in the Hubbard model generalized
by taking into account the inter-atomic exchange interaction and correlated
hopping in partially filled narrow band is considered. Expressions for the
magnetization and Curie temperature as functions of model parameters and band
filling are obtained in the case of weak intra-atomic Coulomb interaction.
Condition of ferromagnetic state realization is found. The obtained results
indicate the important role of correlated hopping.

</DOC>
<DOC>
<DOCNO> 84905 </DOCNO>
A Counterexample to Claimed COBE Constraints on Compact Toroidal


  It has been suggested that if the Universe satisfies a flat, multiply
connected, perturbed Friedmann-Lema^itre model, then cosmic microwave
background data from the COBE satellite implies that the minimum size of the
injectivity diameter (shortest closed spatial geodesic) must be larger than
about two fifths of the horizon diameter. To show that this claim is
misleading, a simple $T^2 \times R$ universe model of injectivity diameter a
quarter of this size, i.e. a tenth of the horizon diameter, is shown to be
consistent with COBE four year observational maps of the cosmic microwave
background. This is done using the identified circles principle.

</DOC>
<DOC>
<DOCNO> 117179 </DOCNO>
What is the Evans-Vigier Field?


  We explain connections of the Evans-Vigier model with theories proposed
previously. The Comay's criticism is proved to be irrelevant.

</DOC>
<DOC>
<DOCNO> 69518 </DOCNO>
QCD corrections up to order alpha_s^2 to polarized quark production in


  The revised version contains two additional references i.e. [13], [14] w.r.t.
to the original paper. Furthermore Eq. (33) in [11] at the end of the paragraph
below (3.17) must be Eq. (33) in [10]. Misprints in the list of references are
corrected.

</DOC>
<DOC>
<DOCNO> 10625 </DOCNO>
Frustrated Order by Disorder: the Pyrochlore Antiferromagnet with Bond


  The classical Heisenberg antiferromagnet on the pyrochlore lattice is
macroscopically and continuously degenerate and the system remains disordered
at all temperatures, even in the presence of weak dilution with nonmagnetic
ions. We show that, in stark contrast, weak bond disorder lifts the ground
state degeneracy in favour of locally collinear spin configurations. We present
a proof that for a single tetrahedron the ground state is perfectly collinear
but identify two mechanisms which preclude the establishment of a globally
collinear state; one due to frustration and the other due to higher-order
effects. We thus obtain a rugged energy landscape, which is necessary to
account for the glassy phenomena found in real systems such as the pyrochlore
Y_2Mo_2O_7 recently reported by Booth et al. [Booth] to contain a substantial
degree of bond disorder.

</DOC>
<DOC>
<DOCNO> 83453 </DOCNO>
Causes and Explanations: A Structural-Model Approach


  We propose new definitions of actual causes and explanations, using
structural equations to model counterfactuals. We show that these definitions
yield a plausible and elegant account of causation and explanation that handles
well examples which have caused problems for other definitions and resolves
major difficulties in the traditional account.

</DOC>
<DOC>
<DOCNO> 13721 </DOCNO>
Magnons in the ferromagnetic Kondo-lattice model


  The magnetic properties of the ferromagnetic Kondo-lattice model (FKLM) are
investigated. Starting from an analysis of the magnon spectrum in the spin-wave
regime, we examine the ferromagnetic stability as a function of the occupation
of the conduction band $n$ and the strength $J$ of the coupling between the
localised moments and the conduction electrons. From the properties of the
spin-wave stiffness $D$ the ferromagnetic phase at zero temperature is derived.
Using an approximate formula the critical temperature $T_c$ is calculated as a
function of $J$ and $n$.

</DOC>
<DOC>
<DOCNO> 83232 </DOCNO>
Computational Complexity and Phase Transitions


  Phase transitions in combinatorial problems have recently been shown to be
useful in locating "hard" instances of combinatorial problems. The connection
between computational complexity and the existence of phase transitions has
been addressed in Statistical Mechanics and Artificial Intelligence, but not
studied rigorously.
  We take a step in this direction by investigating the existence of sharp
thresholds for the class of generalized satisfiability problems defined by
Schaefer. In the case when all constraints are clauses we give a complete
characterization of such problems that have a sharp threshold.
  While NP-completeness does not imply (even in this restricted case) the
existence of a sharp threshold, it "almost implies" this, since clausal
generalized satisfiability problems that lack a sharp threshold are either
  1. polynomial time solvable, or
  2. predicted, with success probability lower bounded by some positive
constant by across all the probability range, by a single, trivial procedure.

</DOC>
<DOC>
<DOCNO> 150606 </DOCNO>
The Holographic RG flow to conformal and non-conformal theory


  We review some aspects of the AdS supergravity description of RG flows. The
case of a flow to an IR CFT can be rigorously studied within the framework of
supergravity. Here we discuss various central charges of the conformal theory
(included the usually neglected ones) and we compare them with QFT
expectations. The case of flows to non-conformal theories is more problematic
in that one usually encounters a naked singularity. We mainly focus on the flow
to an IR N=1 super Yang-Mills theory. We discuss the properties of the solution
and we briefly comment on the fate of the singularity. We also compare the
supergravity results with the expectations of an N=1 SYM at strong coupling.

</DOC>
<DOC>
<DOCNO> 152176 </DOCNO>
Domain Walls in the Large N Limit


  We study BPS saturated domain walls in supersymmetric SU(N) Yang-Mills
theories in the large N limit. We focus on the Seiberg-Witten regime of ${\cal
N}=2$ theory perturbed by a small mass ($m<O(\Lambda/N^4)$) and determine the
wall profile by numerically minimizing its energy density. Similar to the SU(2)
wall studied in a previous work, the SU(N) wall has a five layer structure,
with two confinement phases on the outside, a Coulomb phase in the middle and
two transition regions.

</DOC>
<DOC>
<DOCNO> 150773 </DOCNO>
UV/IR Mixing in Noncommutative Field Theory via Open String Loops


  We explicitly evaluate one-loop (annulus) planar and nonplanar open string
amplitudes in the presence of the background NS-NS two-form field. In the
decoupling limit of Seiberg and Witten, we find that the nonplanar string
amplitudes reproduce the UV/IR mixing of noncommutative field theories. In
particular, the investigation of the UV regime of the open string amplitudes
shows that certain IR closed string degrees of freedom survive the decoupling
limit as previously predicted from the noncommutative field theory analysis.
These degrees of freedom are responsible for the quadratic, linear and
logarithmic IR singularities when the D-branes embedded in space-time have the
codimension zero, one and two, respectively. The analysis is given for both
bosonic and supersymmetric open strings.

</DOC>
<DOC>
<DOCNO> 119823 </DOCNO>
Observational signatures of feedback in QSO absorption spectra


  Models for the formation of galaxies and clusters of galaxies require strong
feedback in order to explain the observed properties of these systems. We
investigate whether such feedback has observational consequences for the
intergalactic medium, as probed in absorption towards background quasars. A
typical quasar sight-line intersects one proto-cluster per unit redshift, and
significant feedback from forming galaxies or AGN, heating the proto-cluster
gas, will result in a large clearing of reduced absorption in the Lyman
alpha-forest. Such a gap could be detected at redshift > 3 when the mean
opacity is high. Feedback from Lyman-break galaxies in proto-clusters can be
probed by the absorption lines produced in their winds. Strong feedback from
galaxies has a major impact on the number and properties of absorption lines
with neutral hydrogen column densities of 10^16/ cm^2. This feedback can be
probed with multiple sight-lines and by studying the unsaturated higher-order
lines of the Lyman series. Galactic winds from dwarf galaxies should break-up
into clouds, in order not to over produce the number of absorption lines. These
clouds can then coast to large distances.

</DOC>
<DOC>
<DOCNO> 116766 </DOCNO>
Lorentz angle measurements in irradiated silicon detectors between 77 K


  Future experiments are using silicon detectors in a high radiation
environment and in high magnetic fields. The radiation tolerance of silicon
improves by cooling it to temperatures below 180 K. At low temperatures the
mobility increases, which leads to larger deflections of the charge carriers by
the Lorentz force. A good knowledge of the Lorentz angle is needed for design
and operation of silicon detectors. We present measurements of the Lorentz
angle between 77 K and 300 K before and after irradiation with a primary beam
of 21 MeV protons.

</DOC>
<DOC>
<DOCNO> 71312 </DOCNO>
Baryon form factors in chiral perturbation theory


  We analyze the electromagnetic form factors of the ground state baryon octet
to fourth order in relativistic baryon chiral perturbation theory. Predictions
for the \Sigma^- charge radius and the \Lambda-\Sigma^0 transition moment are
found to be in excellent agreement with the available experimental information.
Furthermore, the convergence behavior of the hyperon charge radii is shown to
be more than satisfactory.

</DOC>
<DOC>
<DOCNO> 121286 </DOCNO>
Radio observations of the 33.8 ms X-ray pulsar SAX J0635+0533


  The hard X-ray source SAX J0635+0533 shows pulsations at a period of 33.8 ms
and is thought to be associated with a bright Be star. We here report on radio
observations towards this source with the VLA and Arecibo radiotelescopes. With
the VLA we do not detect any radio flux at the Be-star position, but one 4.7
mJy (at a radio frequency of 1.4 GHz) source lies just on the border of the
30'' X-ray error circle. Periodicity searches at 430 MHz performed with the
Arecibo telescope failed to detect any pulsation. We argue that the 4.7 mJy
source is not the radio counterpart of SAX J0635+0533. Most likely SAX
J0635+0533 is a rather ``non-standard'' Be-star/neutron-star X-ray binary
pulsar, probably with a relatively short orbital period. It could still be a
radio emitting pulsar but with an emission beam not pointing toward the Earth.

</DOC>
<DOC>
<DOCNO> 178719 </DOCNO>
Lattice QCD Calculations of Hadron Structure: Constituent Quarks and


  New data from parity-violating experiments on the deuteron now allow
isolation of the strange-quark contribution to the nucleon magnetic moment,
G_M^s(0), without the uncertainty surrounding the anapole moment of the
nucleon. Still, best estimates place G_M^s(0) > 0. It is illustrated how this
experimental result challenges the very cornerstone of the constituent quark
model. The chiral physics giving rise to G_M^s(0) \sim 0 is illustrated.

</DOC>
<DOC>
<DOCNO> 100313 </DOCNO>
Bound of automorphisms of projective varieties of general type


  We prove that there exists a positive number $C_{n}$ depending only on $n$
such that for every smooth projective $n$-fold of general type $X$ defined over
{\bf C}, the automorphism group $Aut(X)$ satisfies the inequality
$\sharp{Aut}(X)\leq C_{n}\cdot\mu (X,K_{X})$, where $\mu (X,K_{X})$ is the
volume of $X$ with respect to $K_{X}$.

</DOC>
<DOC>
<DOCNO> 99605 </DOCNO>
Why would multiplicities be log-concave ?


  It is a basic property of the entropy in statistical physics that is concave
as a function of energy. The analog of this in representation theory would be
the concavity of the logarithm of the multiplicity of an irreducible
representation as a function of its highest weight. We discuss various
situations where such concavity can be established or reasonably conjectured
and consider some implications of this concavity. These are rather informal
notes based on a number of talks I gave on the subject, in particular, at the
1997 International Press lectures at UC Irvine.

</DOC>
<DOC>
<DOCNO> 14116 </DOCNO>
Slow Switching in Globally Coupled Oscillators: Robustness and


  The phenomenon of slow switching in populations of globally coupled
oscillators is discussed. This characteristic collective dynamics, which was
first discovered in a particular class of the phase oscillator model, is a
result of the formation of a heteroclinic loop connecting a pair of clustered
states of the population. We argue that the same behavior can arise in a wider
class of oscillator models with the amplitude degree of freedom. We also argue
how such heteroclinic loops arise inevitably and persist robustly in a
homogeneous population of globally coupled oscillators. Although the
heteroclinic loop might seem to arise only exceptionally, we find that it
appears rather easily by introducing the time-delay in the population which
would otherwise exhibit perfect phase synchrony. We argue that the appearance
of the heteroclinic loop induced by the delayed coupling is then characterized
by transcritical and saddle-node bifurcations. Slow switching arises when the
system with a heteroclinic loop is weakly perturbed. This will be demonstrated
with a vector model by applying weak noises. Other types of weak
symmetry-breaking perturbations can also cause slow switching.

</DOC>
<DOC>
<DOCNO> 101845 </DOCNO>
Variational construction of homoclinics and chaos in presence of a


  We consider autonomous Lagrangian systems with two degrees of freedom, having
an hyperbolic equilibrium of saddle-saddle type (that is the eingenvalues of
the linearized system about the equilibrium are $\pm \lambda_1, \pm \lambda_2
$, $\lambda_1, \lambda_2 > 0$). We assume that $\lambda_1 > \lambda_2$ and that
the system possesses two homoclinic orbits. Under a nondegeneracy assumption on
the homoclinics and under suitable conditions on the geometric behaviour of
these homoclinics near the equilibrium we prove, by variational methods, then
they give rise to an infinite family of multibump homoclinic solutions and that
the topological entropy at the zero energy level is positive. A method to deal
also with homoclinics satisfying a weaker nondegeneracy condition is developed
and it is applied, for simplicity, when $\lambda_1 \approx \lambda_2$. An
application to a perturbation of a uncoupled system is also given.

</DOC>
<DOC>
<DOCNO> 120622 </DOCNO>
Dirac equation in Kerr geometry and its solution


  Chandrasekhar separated the Dirac equation for spinning and massive particles
in Kerr geometry into radial and angular parts. In the present review, we
present solutions of the complete wave equation and discuss how the Dirac wave
scatters off Kerr black holes. The eigenfunctions, eigenvalues and reflection
and transmission co-efficients are computed for different Kerr parameters. We
compare the solutions with several parameters to show how a spinning black hole
distinguishes mass and energy of incoming waves. Very close to the horizon, the
solutions become independent of the particle parameters indicating an
universality of the behaviour.

</DOC>
<DOC>
<DOCNO> 83397 </DOCNO>
The Concurrent Language Aldwych


  Aldwych is proposed as the foundation of a general purpose language for
parallel applications. It works on a rule-based principle, and has aspects
variously of concurrent functional, logic and object-oriented languages, yet it
forms an integrated whole. It is intended to be applicable both for small-scale
parallel programming, and for large-scale open systems.

</DOC>
<DOC>
<DOCNO> 12239 </DOCNO>
Phase Transitions and Oscillations in a Lattice Prey-Predator Model


  A coarse grained description of a two-dimensional prey-predator system is
given in terms of a 3-state lattice model containing two control parameters:
the spreading rates of preys and predators. The properties of the model are
investigated by dynamical mean-field approximations and extensive numerical
simulations. It is shown that the stationary state phase diagram is divided
into two phases: a pure prey phase and a coexistence phase of preys and
predators in which temporal and spatial oscillations can be present. The
different type of phase transitions occuring at the boundary of the prey
absorbing phase, as well as the crossover phenomena occuring between the
oscillatory and non-oscillatory domains of the coexistence phase are studied.
The importance of finite size effects are discussed and scaling relations
between different quantities are established. Finally, physical arguments,
based on the spatial structure of the model, are given to explain the
underlying mechanism leading to oscillations.

</DOC>
<DOC>
<DOCNO> 102371 </DOCNO>
On the dimension of discrete valuations of k((X1,...,Xn))


  Let $v$ be a rank-one discrete valuation of the field $k((\X))$. We know,
after \cite{Bri2}, that if $n=2$ then the dimension of $v$ is 1 and if $v$ is
the usual order function over $k((\X))$ its dimension is $n-1$. In this paper
we prove that, in the general case, the dimension of a rank-one discrete
valuation can be any number between 1 and $n-1$.

</DOC>
<DOC>
<DOCNO> 8350 </DOCNO>
Memory Effect, Rejuvenation and Chaos Effect in the Multi-layer Random


  We introduce magnetization to the Multi-layer Random Energy Model which has a
hierarchical structure, and perform Monte Carlo simulation to observe the
behavior of ac-susceptibility. We find that this model is able to reproduce
three prominent features of spin glasses, i.e., memory effect, rejuvenation and
chaos effect, which were found recently by various experiments on aging
phenomena with temperature variations.

</DOC>
<DOC>
<DOCNO> 116760 </DOCNO>
Clustering, Crosstalk and Signalling of Cell Receptors


  We propose a general theory of cooperativity between transmembrane receptors
of a cell. Based on a conformation-dependent interaction between
nearest-neighboring receptors, the sensitive signalling and the enhancement of
clustering, or oligomerization, are explained as two responses to ligand
binding. In this model, ligand binding shifts the energy difference between the
two conformational states. In order to decrease the total energy of the system,
neighboring receptors tend to have a same conformational state, while receptors
with the same conformational state tend to cluster together. In the presence of
noise, there is a probability distribution of various configurations of the
system. This situation is investigated by using methods of statistical
mechanics. By choosing an appropriate value of coupling-noise-ratio, any degree
of signalling sensitivity that fits the reality can be obtained. On the other
hand, ligand binding enhances the clustering if the threshold value of the
receptor conformational change is within a certain range.

</DOC>
<DOC>
<DOCNO> 170353 </DOCNO>
Uncertainty Relations for Entangled States


  A generalized uncertainty relation for an entangled pair of particles is
obtained if we impose a symmetrization rule for all operators that we should
use when doing any calculation using the entangled wave function of the pair.
This new relation reduces to Heisenberg's uncertainty relation when the
particles have no correlation and suggests that we can have new lower bounds
for the product of position and momentum dispersions.

</DOC>
<DOC>
<DOCNO> 68994 </DOCNO>
B_{s,d} -> l+ l- in a Two-Higgs-Doublet Model


  We compute the branching fractions of B_{s,d} -> l+ l- in the type-II
two-Higgs-doublet model with large tan(beta). We find that the parameters of
the neutral Higgs sector of the two-Higgs-doublet model cancel in the result,
so that the branching fractions depend only on the charged Higgs mass and
tan(beta). For large values of tan(beta) and a charged Higgs mass above the
bound from b -> s gamma, we find that the branching fractions can be enhanced
by up to an order of magnitude or suppressed by up to a factor of two compared
to the Standard Model result. We point out that previous calculations in the
literature are gauge-dependent due to the omission of an important diagram,
which gives the dominant contribution in the 't Hooft-Feynman gauge. We have
analyzed in detail the region of the (M_{H^+}, tan(beta)) plane to be probed by
searches for B_s -> mu+ mu- in Run II of the Tevatron. Since the branching
fraction increases like tan^4(beta), this decay mode is complementary to b -> s
gamma and efficiently probes the large tan(beta) region. For tan(beta)=60, an
integrated luminosity of 20 fb^{-1} in an extended Run II will probe charged
Higgs masses up to 260 GeV, if the background to B_s -> mu+ mu- is small. For
the same value of tan(beta), the LHC may be able to explore charged Higgs
masses up to 1 TeV using this decay.

</DOC>
<DOC>
<DOCNO> 118636 </DOCNO>
Adenine Abundance in a Collapsing Molecular Cloud


  A vital ingredient of DNA molecule named adenine may be produced by
successive addition of HCN during molecular cloud collapse and star formation.
We compute its abundance in a collapsing cloud as a function of the reaction
rate and show that in much of the circumstances the resulting amount may be
sufficient to contaminate planets, comets and meteorites. We introduce a
$f$-parameter which may be used to study the abundance where radiative
association takes place.

</DOC>
<DOC>
<DOCNO> 83159 </DOCNO>
Image Compression with Iterated Function Systems, Finite Automata and


  Fractal image compression, Culik's image compression and zerotree prediction
coding of wavelet image decomposition coefficients succeed only because typical
images being compressed possess a significant degree of self-similarity.
Besides the common concept, these methods turn out to be even more tightly
related, to the point of algorithmical reducibility of one technique to
another. The goal of the present paper is to demonstrate these relations.
  The paper offers a plain-term interpretation of Culik's image compression, in
regular image processing terms, without resorting to finite state machines and
similar lofty language. The interpretation is shown to be algorithmically
related to an IFS fractal image compression method: an IFS can be exactly
transformed into Culik's image code. Using this transformation, we will prove
that in a self-similar (part of an) image any zero wavelet coefficient is the
root of a zerotree, or its branch.
  The paper discusses the zerotree coding of (wavelet/projection) coefficients
as a common predictor/corrector, applied vertically through different layers of
a multiresolutional decomposition, rather than within the same view. This
interpretation leads to an insight into the evolution of image compression
techniques: from a causal single-layer prediction, to non-causal same-view
predictions (wavelet decomposition among others) and to a causal cross-layer
prediction (zero-trees, Culik's method).

</DOC>
<DOC>
<DOCNO> 40108 </DOCNO>
Experimentation and Physics at a Future Electron-Positron Linear


  I summarise the physics opportunities and experimental challenges at future
Linear Colliders, using material from the recent ECFA/DESY workshop on the
subject as well as contributions to the series of worldwide studies. For
reasons of economy, the discussion is restricted to the European Tesla project
and to its electron-positron mode only.

</DOC>
<DOC>
<DOCNO> 12559 </DOCNO>
Influence of Quantum Hall Effect on Linear and Nonlinear Conductivity in


  We report a detailed characterization of quantum Hall effect (QHE) influence
on the linear and non-linear resistivity tensor in FISDW phases of the organic
conductor (TMTSF)2PF6. We show that the behavior at low electric fields,
observed for nominally pure single crystals with different values of the
resistivity ratio, is fully consistent with a theoretical model, which takes
QHE nature of FISDW and residual quasi-particle density associated with
different crystal imperfection levels into account. The non-linearity in
longitudinal and diagonal resistivity tensor components observed at large
electric fields reconciles preceding contradictory results. Our theoretical
model offers a qualitatively good explanation of the observed features if a
sliding of the density wave with the concomitant destruction of QHE, switched
on above a finite electric field, is taken into account.

</DOC>
<DOC>
<DOCNO> 12957 </DOCNO>
Finite-Size Correlation Length and Violations of Finite-Size Scaling


  We address the problem of the definition of the finite-volume correlation
length. First, we study the large-N limit of the N-vector model, and we show
the existence of several constraints on the definition if regularity of the
finite-size scaling functions and correct anomalous behaviour above the upper
critical dimension are required. Then, we study in detail a model in which the
zero mode in prohibited. Such a model is a generalization of the
fixed-magnetization Ising model which is equivalent to the lattice gas. Also in
this case, we find that the finite-volume correlation length must satisfy
appropriate constraints in order to obtain regular finite-size scaling
functions, and, above the upper critical dimension, an anomalous scaling
behaviour. The large-N results are confirmed by a one-loop calculation in the
lattice $\phi^4$ theory.

</DOC>
<DOC>
<DOCNO> 101652 </DOCNO>
Multiplicity of Invariant Algebraic Curves and Darboux Integrability


  We define four different kinds of multiplicity of an invariant algebraic
curve for a given polynomial vector field and investigate their relationships.
After taking a closer look at the singularities and at the line of infinity, we
improve the Darboux theory of integrability using these new notions of
multiplicity.

</DOC>
<DOC>
<DOCNO> 85129 </DOCNO>
Circular Cosmic String Loop in Brans-Dicke Theory


  The gravitational field of a stationary circular cosmic string loop
,externally supported against collapse, is investigated in the context of
Brans-Dicke theory in the weak field approximation of the field equations. The
solution is quasi-conformally related to the corresponding solution in
Einstein's General Relativity(GR) and goes over to the corresponding solution
in GR when the Brans-Dicke parameter $\omega $ becomes infinitely large.

</DOC>
<DOC>
<DOCNO> 11068 </DOCNO>
Nonlinear I-V, High Flux-Flow Velocity Instability and Evidence for


  The large flux-flow velocity behavior of the high temperature superconductor
BSCCO in the mixed state is studied by measurement of the current-voltage
characteristic as a function of temperature and magnetic field direction. We
find strong evidence for vortex-antivortex pairs that are excited by quantum
fluctuations and contribute to the dissipation when dissociated by a large
current.

</DOC>
<DOC>
<DOCNO> 71887 </DOCNO>
Hyperon semileptonic decay constants and quark-spin content of the octet


  We present the recent investigation on the effect of the SU(3) symmetry
breaking in the spin structure of the octet baryons.

</DOC>
<DOC>
<DOCNO> 152459 </DOCNO>
Spin(p+1,p+1) Covariant Dp-brane Bound States


  We construct Spin(p+1,p+1) covariant Dp-brane bound states by using that the
potentials in the RR sector of toroidically compactified type II supergravity
transform as a chiral spinor of the T-duality group. As an application, we show
the invariance of the zero-force condition for a probe D-brane under
noncommutative deformations of the background, which gives a holographic proof
of the stability of the corresponding field theory ground state under
noncommutative deformations. We also identify the Spin(p+1,p+1) transformation
laws by examining the covariance of the D-brane Lagrangians.

</DOC>
<DOC>
<DOCNO> 151931 </DOCNO>
Constraints on $AdS_5$ Embeddings


  We show that the embedding of either a static or a time dependent maximally
3-symmetric brane with non-zero spatial curvature $k$ into a non-compactified
$AdS_5$ bulk does not yield exponential suppression of the geometry away from
the brane. Implications of this result for brane-localized gravity are
discussed.

</DOC>
<DOC>
<DOCNO> 10427 </DOCNO>
How an Anomalous Cusp Bifurcates


  We study the pattern of activated trajectories in a double well system
without detailed balance, in the weak noise limit. The pattern may contain
cusps and other singular features, which are similar to the caustics of
geometrical optics. Their presence is reflected in the quasipotential of the
system, much as phase transitions are reflected in the free energy of a
thermodynamic system. By tuning system parameters, a cusp may be made to
coincide with the saddle point. Such an anomalous cusp is analogous to a
nonclassical critical point. We derive a scaling law, and nonpolynomial
`equations of state', that govern its bifurcation into conventional cusps.

</DOC>
<DOC>
<DOCNO> 83201 </DOCNO>
Application Software, Domain-Specific Languages, and Language Design


  While application software does the real work, domain-specific languages
(DSLs) are tools to help produce it efficiently, and language design assistants
in turn are meta-tools to help produce DSLs quickly. DSLs are already in wide
use (HTML for web pages, Excel macros for spreadsheet applications, VHDL for
hardware design, ...), but many more will be needed for both new as well as
existing application domains. Language design assistants to help develop them
currently exist only in the basic form of language development systems. After a
quick look at domain-specific languages, and especially their relationship to
application libraries, we survey existing language development systems and give
an outline of future language design assistants.

</DOC>
<DOC>
<DOCNO> 120347 </DOCNO>
An excess of very bright stars in the inner bulge


  From an analysis of the stars remaining in central regions of the Galaxy
after subtracting those belonging to the disc and the bulge, we deduce that the
inner bulge must have an extra young population with respect the rest of the
bulge. It is shown that there is a higher ratio of very bright stars in the
central bulge than than there is in the outer bulge. This is interpreted as
being an additional young component due to the presence of star formation
regions near the Galactic Centre which is absent in the outer bulge.

</DOC>
<DOC>
<DOCNO> 11760 </DOCNO>
Universal amplitude-exponent relation for the Ising model on sphere-like


  Conformal field theory predicts finite-size scaling amplitudes of correlation
lengths universally related to critical exponents on sphere-like, semi-finite
systems $S^{d-1}\times\mathbb{R}$ of arbitrary dimensionality $d$. Numerical
studies have up to now been unable to validate this result due to the
intricacies of lattice discretisation of such curved spaces. We present a
cluster-update Monte Carlo study of the Ising model on a three-dimensional
geometry using slightly irregular lattices that confirms the validity of a
linear amplitude-exponent relation to high precision.

</DOC>
<DOC>
<DOCNO> 70659 </DOCNO>
Analysis of $B \to K\pi$ decays with small elastic final state


  An analysis of $B \to K\pi$ decays is given, assuming a small elastic $\pi K
$ rescattering phase difference.Using factorization model only for the
tree-level and electroweak penguin amplitudes, we show that the strong penguin
amplitude, its absorptive part and the CP-violation weak phase $\gamma$ can be
obtained from the measured $B \to K\pi$ branching ratios. The strength of the
strong penguin and its absorptive part thus obtained from the CLEO data, are
found to be very close to factorization model values and suggests a current $s$
quark mass around $m_{s} = 106 \rm MeV$. The central value of $\gamma$ is found
to be around $76.10^{\circ}$, with a possible value in the range
$50^{\circ}-100^{\circ}$. 

</DOC>
<DOC>
<DOCNO> 151786 </DOCNO>
*-TREK: The One-Loop N=4 Noncommutative SYM Action


  We investigate N=4 noncommutative super Yang-Mills (SYM) theory. We compute
the one-loop four gauge boson scattering amplitude on parallel Dp-branes, and
find the corresponding contribution to the noncommutative SYM one-loop action
in a momentum expansion. The result is somewhat surprising. We find that while
the planar diagram can be written using the usual *-product, the contributions
from nonplanar diagrams in general involve additional structure beyond the
*-product, arising from the nontrivial worldsheet correlations surviving the
field theory limit. To each nonplanar diagram, depending on the number n of
external vertex operator insertions on each boundary, there is a corresponding
*_n n-ary operation. We further find that it is no longer possible to write
down an off-shell gauge invariant one-loop effective action using the
noncommutative field strength defined at tree-level.

</DOC>
<DOC>
<DOCNO> 68501 </DOCNO>
Bottom Production


  We review the prospects for bottom production physics at the LHC.

</DOC>
<DOC>
<DOCNO> 39755 </DOCNO>
Measurement of the e+e- -> Z gamma gamma Cross Section and Determination


  A first measurement of the cross section of the process e+e- -> Z gamma gamma
is reported using a total integrated luminosity of 231 pb^-1 collected with the
L3 detector at centre-of-mass energies of 182.7 GeV and 188.7 GeV. By selecting
hadronic events with two isolated photons the e+e- -> Z gamma gamma cross
section is measured to be 0.49 +0.20 -0.17 +/- 0.04 pb at 182.7 GeV and 0.47
+/- 0.10 +/- 0.04 pb at 188.7 GeV. The measurements are consistent with
Standard Model expectations. Limits on Quartic Gauge Boson Couplings
a_0/Lambda^2 and a_c/Lambda^2 of -0.009 GeV^-2 < a_0/Lambda^2 < 0.008 GeV^-2
and -0.007 GeV^-2 < a_c/Lambda^2 < 0.013 GeV^-2 are derived at 95% confidence
level.

</DOC>
<DOC>
<DOCNO> 12789 </DOCNO>
A.model of cation ordering in A(B'_xB''_1-x)O_3 relaxors


  We have shown that the lattice-gas model with four repulsive pair interaction
constants (corresponding to the four nearest coordination shells) on a simple
cubic lattice is a sufficient model to describe the main types of cation
ordering in relaxors. The phase diagram, obtained by the cluster variation
method, shows the sequences of transitions between the phases 1:2 - 1:1 -
disordered and 1:2 - disordered.

</DOC>
<DOC>
<DOCNO> 39850 </DOCNO>
Report of the SUGRA Working Group for Run II of the Tevatron


  We present an analysis of the discovery reach for supersymmetric particles at
the upgraded Tevatron collider, assuming that SUSY breaking results in
universal soft breaking parameters at the grand unification scale, and that the
lightest supersymmetric particle is stable and neutral. We first present a
review of the literature, including the issues of unification, renormalization
group evolution of the supersymmetry breaking parameters and the effect of
radiative corrections on the effective low energy couplings and masses of the
theory. We consider the experimental bounds coming from direct searches and
those arising indirectly from precision data, cosmology and the requirement of
vacuum stability. The issues of flavor and CP-violation are also addressed. The
main subject of this study is to update sparticle production cross sections,
make improved estimates of backgrounds, delineate the discovery reach in the
supergravity framework, and examine how this might vary when assumptions about
universality of soft breaking parameters are relaxed. With 30 fb$^{-1}$
luminosity and one detector, charginos and neutralinos, as well as third
generation squarks, can be seen if their masses are not larger than 200-250
GeV, while first and second generation squarks and gluinos can be discovered if
their masses do not significantly exceed 400 GeV. We conclude that there are
important and exciting physics opportunities at the Tevatron collider, which
will be significantly enhanced by continued Tevatron operation beyond the first
phase of Run II.

</DOC>
<DOC>
<DOCNO> 71164 </DOCNO>
Statistical Coalescence Model with Exact Charm Conservation


  The statistical coalescence model for the production of open and hidden charm
is considered within the canonical ensemble formulation. The data for the J/psi
multiplicity in Pb+Pb collisions at 158 A GeV are used for the model prediction
of the open charm yield which has not yet been measured in these reactions.

</DOC>
<DOC>
<DOCNO> 69259 </DOCNO>
The standard and degenerate primordial nucleosynthesis versus recent


  We report the results on Big Bang Nucleosynthesis (BBN) based on an updated
code, with accuracy of the order of 0.1% on He4 abundance, compared with the
predictions of other recent similar analysis. We discuss the compatibility of
the theoretical results, for vanishing neutrino chemical potentials, with the
observational data. Bounds on the number of relativistic neutrinos and baryon
abundance are obtained by a likelihood analysis. We also analyze the effect of
large neutrino chemical potentials on primordial nucleosynthesis, motivated by
the recent results on the Cosmic Microwave Background Radiation spectrum. The
BBN exclusion plots for electron neutrino chemical potential and the effective
number of relativistic neutrinos are reported. We find that the standard BBN
seems to be only marginally in agreement with the recent BOOMERANG and MAXIMA-1
results, while the agreement is much better for degenerate BBN scenarios for
large effective number of neutrinos, N_\nu \sim 10.

</DOC>
<DOC>
<DOCNO> 7971 </DOCNO>
Semi-classical magnetoresistance in weakly modulated magnetic fields


  The semi-classical conductance of a two-dimensional electron gas is
calculated in the presence of a one-dimensional modulated magnetic field with
zero average. In the limit of small magnetic field amplitudes (B) the
contribution of the magnetic modulation to the magnetoresistance increases as
$B^{3/2}$ in the diffusive limit, while the increase is linear in $B$ in the
ballistic regime. Temperature does not influence the power law behavior but it
decreases the prefactor of this functional behavior.

</DOC>
<DOC>
<DOCNO> 102219 </DOCNO>
The moduli space of Riemann surfaces is Kahler hyperbolic


  Let $\cM_{g,n}$ be the moduli space of Riemann surfaces of genus $g$ with $n$
punctures.
  From a complex perspective, moduli space is hyperbolic. For example,
$\cM_{g,n}$ is abundantly populated by immersed holomorphic disks of constant
curvature -1 in the Teichm\"uller (=Kobayashi) metric.
  When $r=\dim_{\cx} \cM_{g,n}$ is greater than one, however, $\cM_{g,n}$
carries no complete metric of bounded negative curvature. Instead, Dehn twists
give chains of subgroups $\zed^r \subset \pi_1(\cM_{g,n})$ reminiscent of flats
in symmetric spaces of rank $r>1$.
  In this paper we introduce a new K\"ahler metric on moduli space that
exhibits its hyperbolic tendencies in a form compatible with higher rank.

</DOC>
<DOC>
<DOCNO> 68428 </DOCNO>
Spin content of the $\Lambda$ hyperon


  Using the known experimental data for the hyperon semileptonic decay
constants, we calculate integrated quark densities $\Delta q_\Lambda$ and $%
\Delta \Sigma_\Lambda$ for the hyperon $\Lambda$ with flavor SU(3) symmetry
breaking taken into account. Symmetry breaking is implemented with the help of
the chiral quark-soliton model in an approach, in which the dynamical
parameters are fixed by the experimental data for six hyperon semileptonic
decay constants. This parametrization allows us to reproduce the first moment
of the $g_1^{{\rm p}}(x)$ of the proton. For the $\Lambda$ we obtain: $\Delta
u_{\Lambda}=\Delta d_{\Lambda} \approx 0$ and $\Delta s_{\Lambda}$ of the order
of 1. Unfortunately large experimental errors of $\Xi^-$ decays propagate in
our analysis especially in the case of $\Delta\Sigma_{\Lambda}$ and $\Delta
s_{\Lambda}$. Only if the errors for these decays are reduced, the accurate
theoretical predictions for $\Delta\Sigma_{\Lambda}$ and $% \Delta s_{\Lambda}$
will be possible.

</DOC>
<DOC>
<DOCNO> 118366 </DOCNO>
Studying the Pulsation of Mira Variables in the Ultraviolet


  We present results from an empirical study of the Mg II h & k emission lines
of selected Mira variable stars, using spectra from the International
Ultraviolet Explorer (IUE). The stars all exhibit similar Mg II behavior during
the course of their pulsation cycles. The Mg II flux always peaks after optical
maximum near pulsation phase 0.2-0.5, although the Mg II flux can vary greatly
from one cycle to the next. The lines are highly blueshifted, with the
magnitude of the blueshift decreasing with phase. The widths of the Mg II lines
are also phase-dependent, decreasing from about 70 km/s to 40 km/s between
phase 0.2 and 0.6. We also study other UV emission lines apparent in the IUE
spectra, most of them Fe II lines. These lines are much narrower and not nearly
as blueshifted as the Mg II lines. They exhibit the same phase-dependent flux
behavior as Mg II, but they do not show similar velocity or width variations.

</DOC>
<DOC>
<DOCNO> 169677 </DOCNO>
Tailoring of vibrational state populations with light-induced potentials


  We propose a method for achieving highly efficient transfer between the
vibrational states in a diatomic molecule. The process is mediated by strong
laser pulses and can be understood in terms of light-induced potentials. In
addition to describing a specific molecular system, our results show how, in
general, one can manipulate the populations of the different quantum states in
double well systems.

</DOC>
<DOC>
<DOCNO> 170676 </DOCNO>
On the mystery of quantum probabilistic rule: trigonometric and


  We demonstrate the quantum probabilistic rule (which differ from classical
Bayes' formula by the cosinus factor) can be obtained on purely classical basis
as a consequence of the perturbation effect of preparation procedures. In any
case the interference can be easily simulated for macrosystems. Moreover, we
obtain the classification of all possible transformations of probablities which
can arise via perturbation effects. There are two main transformation classes:
with trigonometric and hyperbolic ("interference") perturbations of classical
Bayes' formula. Quantum probabilistic rule is just a particular case of
trigonometric probablistic behaviour. Hyperbolic probablistic behaviour can be
easily simulated. However, the question of its observation for "real physical
phenomena" is open.

</DOC>
<DOC>
<DOCNO> 118440 </DOCNO>
Kaon Condensation in Proto-Neutron Star Matter


  We study the equation of state (EOS) of kaon-condensed matter including the
effects of temperature and trapped neutrinos. It is found that the order of the
phase transition to a kaon-condensed phase, and whether or not Gibbs' rules for
phase equilibrium can be satisfied in the case of a first order transition,
depend sensitively on the choice of the kaon-nucleon interaction. The main
effect of finite temperature, for any value of the lepton fraction, is to mute
the effects of a first order transition, so that the thermodynamics becomes
similar to that of a second order transition. Above a critical temperature,
found to be at least 30--60 MeV depending upon the interaction, the first order
transition disappears. The phase boundaries in baryon density versus lepton
number and baryon density versus temperature planes are delineated. We find
that the thermal effects on the maximum gravitational mass of neutron stars are
as important as the effects of trapped neutrinos, in contrast to previously
studied cases in which the matter contained only nucleons or in which hyperons
and/or quark matter were considered. Kaon-condensed EOSs permit the existence
of metastable neutron stars, because the maximum mass of an initially hot,
lepton-rich protoneutron star is greater than that of a cold, deleptonized
neutron star. The large thermal effects imply that a metastable protoneutron
star's collapse to a black hole could occur much later than in previously
studied cases that allow metastable configurations.

</DOC>
<DOC>
<DOCNO> 122262 </DOCNO>
Power spectrum normalization from the local abundance of rich clusters


  The number density of rich galaxy clusters still provides the most robust way
of normalizing the power spectrum of dark matter perturbations on scales
relevant to large-scale structure. We revisit this constraint in light of
several recent developments: (1) the availability of well-defined samples of
local clusters with relatively accurate X-ray temperatures; (2) new theoretical
mass functions for dark matter haloes which provide a good fit to large
numerical simulations; (3) more accurate mass-temperature relations from larger
catalogs of hydrodynamical simulations; (4) the requirement to consider closed
as well as open and flat cosmologies to obtain full multi-parameter likelihood
constraints for CMB and SNe studies. We present a new sample of clusters drawn
from the literature and use this sample to obtain improved results on sigma_8,
the normalization of the matter power spectrum on scales of 8 h^{-1} Mpc, as a
function of the matter density and cosmological constant in a Universe with
general curvature. We discuss our differences with previous work, and the
remaining major sources of uncertainty. Final results on the 68 per cent
confidence region, approximately independent of power spectrum shape, can be
expressed as constraints on sigma at an appropriate cluster normalization scale
R_Cl. We provide fitting formulas for R_Cl and sigma(R_Cl) for general
cosmologies, as well as for sigma_8 as a function of cosmology and shape
parameter Gamma. For flat models we find approximately sigma_8 \simeq
0.495^{+0.034}_{-0.037}) Omega_M^{-0.60} for Gamma=0.23, where the error bar is
dominated by uncertainty in the mass-temperature relation.

</DOC>
<DOC>
<DOCNO> 119114 </DOCNO>
Discovery of Narrow X-ray Absorption Lines from NGC 3783 with the


  We present the first grating-resolution X-ray spectra of the Seyfert 1 galaxy
NGC 3783, obtained with the High Energy Transmission Grating Spectrometer on
the Chandra X-ray Observatory. These spectra reveal many narrow absorption
lines from the H-like and He-like ions of O, Ne, Mg, Si, S and Ar, as well as
FeXVII-FeXXI L-shell lines. We have also identified several weak emission
lines, mainly from O and Ne. The absorption lines are blueshifted by a mean
velocity of approximately 440\pm200 km/s and are not resolved, indicating a
velocity dispersion within the absorbing gas of a few hundred km/s or less. We
measure the lines' equivalent widths and compare them with the predictions of
photoionization models. The best-fitting model has a microturbulence velocity
of 150 km/s and a hydrogen column density of 1.3\times10^22 cm^-2. The measured
blueshifts and inferred velocity dispersions of the X-ray absorption lines are
consistent with those of the strongest UV absorption lines observed in this
object. However, simple models that propose to strictly unify the X-ray and UV
absorbers have difficulty explaining simultaneously the X-ray and UV absorption
line strengths.

</DOC>
<DOC>
<DOCNO> 8817 </DOCNO>
Quenched Spin Tunneling and Diabolical Points in Magnetic Molecules: II.


  The perfect quenching of spin tunneling first predicted for a model with
biaxial symmetry, and recently observed in the magnetic molecule Fe_8, is
further studied using the discrete phase integral (or
Wentzel-Kramers-Brillouin) method. The analysis of the previous paper is
extended to the case where the magnetic field has both hard and easy
components, so that the Hamiltonian has no obvious symmetry. Herring's formula
is now inapplicable, so the problem is solved by finding the wavefunction and
using connection formulas at every turning point. A general formula for the
energy surface in the vicinity of the diabolo is obtained in this way. This
formula gives the tunneling apmplitude between two wells unrelated by symmetry
in terms of a small number of action integrals, and appears to be generally
valid, even for problems where the recursion contains more than five terms.
Explicit results are obtained for the diabolical points in the model for Fe_8.
These results exactly parallel the experimental observations. It is found that
the leading semiclassical results for the diabolical points appear to be exact,
and the points themselves lie on a perfect centered rectangular lattice in the
magnetic field space. A variety of evidence in favor of this perfect lattice
hypothesis is presented.

</DOC>
<DOC>
<DOCNO> 8272 </DOCNO>
Magnetic properties of the Hubbard model on three-dimensional lattices:


  The relation between three-dimensional lattice structure and magnetism in
correlated electron systems is explored for face centered cubic (FCC), body
centered cubic (BCC), and simple cubic (SC) lattices. In particular, we
question which lattice structure has the strongest tendency toward the
ferromagnetism or antiferromagnetism. We employ the Hubbard model to calculate
the spin susceptibility and the single-particle spectrum with the
fluctuation-exchange (FLEX) and the two-particle self-consistent (TPSC)
approximations in the weak coupling regime. We have shown that (i)
ferromagnetic spin fluctuations become dominant when the Fermi level lies
around a sharp peak (divergence) in the density of states (D(E)) near the
bottom of the band, which occurs for FCC with/without next nearest neighbor
hoppings (t') or BCC with an appropriate value of t'. Among the cases studied,
the ferromagnetic fluctuation is found to be the strongest for FCC with a
finite t'. (ii) When the peak in D(E) resides around the band center as in
bipartite SC or BCC, antiferromagnetic fluctuations become dominant when the
band is close to the half-filling, with the fluctuation being much stronger in
BCC.

</DOC>
<DOC>
<DOCNO> 102896 </DOCNO>
Logarithm-free A-hypergeometric series


  We give a dimension formula for the space of logarithm-free series solutions
to an A-hypergeometric (or a GKZ hypergeometric) system. In the case where the
convex hull spanned by A is a simplex, we give a rank formula for the system,
characterize the exceptional set, and prove the equivalence of the
Cohen-Macaulayness of the toric variety defined by A with the emptiness of the
exceptional set. Furthermore we classify A-hypergeometric systems as analytic
D-modules.

</DOC>
<DOC>
<DOCNO> 84264 </DOCNO>
Gravitational Collapse of Dust with a Cosmological Constant


  The recent analysis of Markovic and Shapiro on the effect of a cosmological
constant on the evolution of a spherically symmetric homogeneous dust ball is
extended to include the inhomogeneous and degenerate cases. The histories are
shown by way of effective potential and Penrose-Carter diagrams.

</DOC>
<DOC>
<DOCNO> 101568 </DOCNO>
The Steinhaus tiling problem and the range of certain quadratic forms


  We give a short proof of the fact that there are no measurable subsets of
Euclidean space (in dimension d > 2), which, no matter how translated and
rotated, always contain exactly one integer lattice point. In dimension d=2
(the original Steinhaus problem) the question remains open.

</DOC>
<DOC>
<DOCNO> 80595 </DOCNO>
The Stefan-Boltzmann law: SU(2) versus SO(3) lattice gauge theory


  We investigate the high temperature limit of SU(2) and SO(3) lattice gauge
theory, respectively. In particular, we study the Stefan-Boltzmann constant in
both cases. As is well known, the Stefan-Boltzmann constant extracted from
SU(2) lattice gauge theory by incorporating finite size effects is smaller than
the continuum value which assumes three gluon degrees of freedom. On the other
hand, the extrapolation of our SO(3) lattice data comes much closer to the
continuum value. This rises the question whether SU(2) and SO(3) lattice gauge
theories represent different quantum theories in the continuum limit.

</DOC>
<DOC>
<DOCNO> 72056 </DOCNO>
Pion Interferometry at RHIC: Probing a thermalized Quark-Gluon-Plasma?


  We calculate the Gaussian radius parameters of the pion-emitting source in
high energy heavy ion collisions, assuming a first order phase transition from
a thermalized Quark-Gluon-Plasma (QGP) to a gas of hadrons. Such a model leads
to a very long-lived dissipative hadronic rescattering phase which dominates
the properties of the two-pion correlation functions. The radii are found to
depend only weakly on the thermalization time tau_i, the critical temperature
T_c (and thus the latent heat), and the specific entropy of the QGP. The
dissipative hadronic stage enforces large variations of the pion emission times
around the mean. Therefore, the model calculations suggest a rapid increase of
R_out/R_side as a function of K_T if a thermalized QGP were formed.

</DOC>
<DOC>
<DOCNO> 99850 </DOCNO>
Rigidity of measurable structure for Z^d-actions by automorphisms of a


  We show that for certain classes of actions of Z^d, d >= 2, by automorphisms
of the torus any measurable conjugacy has to be affine, hence measurable
conjugacy implies algebraic conjugacy; similarly any measurable factor is
algebraic, and algebraic and affine centralizers provide invariants of
measurable conjugacy. Using the algebraic machinery of dual modules and
information about class numbers of algebraic number fields we consruct various
examples of Z^d-actions by Bernoulli automorphisms whose measurable orbit
structure is rigid, including actions which are weakly isomorphic but not
isomorphic. We show that the structure of the centralizer for these actions may
or may not serve as a distinguishing measure-theoretic invariant.

</DOC>
<DOC>
<DOCNO> 119659 </DOCNO>
A Decaying Ultra Heavy Dark Matter (WIMPZILLA): Review of Recent


  Recent theoretical and observational motivations for existence of a decaying
Ultra Heavy Dark Matter (UHDM) are reviewed. We show that present data from
Ultra High Energy Cosmic Rays (UHECRs) and SN - Ia are compatible with a
relatively short lifetime of UHDM.

</DOC>
<DOC>
<DOCNO> 120743 </DOCNO>
The Galactic Thick Disk Stellar Abundances


  We present first results from a program to measure the chemical abundances of
a large (N>30) sample of thick disk stars with the principal goal of
investigating the formation history of the Galactic thick disk. Our analysis
confirms previous studies of O and Mg in the thick disk stars which reported
enhancements in excess of the thin disk population. Furthermore, the
observations of Si, Ca, Ti, Mn, Co, V, Zn, Al, and Eu all argue that the thick
disk population has a distinct chemical history from the thin disk. With the
exception of V and Co, the thick disk abundance patterns match or tend towards
the values observed for halo stars with [Fe/H]~-1. This suggests that the thick
disk stars had a chemical enrichment history similar to the metal-rich halo
stars. With the possible exception of Si, the thick disk abundance patterns are
in excellent agreement with the chemical abundances observed in the metal-poor
bulge stars suggesting the two populations formed from the same gas reservoir
at a common epoch.
  We discuss the implications for the formation of the thick disk, new insights
presented for theories of nucleosynthesis, and the impact on interpretations of
the abundance patterns of the damped Lya systems at high redshift.
[significantly abridged]

</DOC>
<DOC>
<DOCNO> 151467 </DOCNO>
Superstring action in AdS_5 x S^5: kappa symmetry light cone gauge


  As part of program to quantize superstrings in AdS_5 x S^5 background in
light cone approach we find the explicit form of the corresponding
Green-Schwarz action in fermionic light-cone kappa-symmetry gauge. The
resulting action is quadratic and quartic in fermions. In the flat space limit
it reduces to the standard light-cone Green-Schwarz action, and also has the
correct superparticle limit. We discuss fixing the bosonic light-cone gauge and
a reformulation of the action in terms of 2-d Dirac spinors.

</DOC>
<DOC>
<DOCNO> 116240 </DOCNO>
Newtownian Relativity, Gravity, and Cosmology


  Well-known to specialists but little-known to the wider audience is that
Newtonian gravity can be understood as geodesic motion in space-time, where
time is absolute and space is Euclidean. Newtonian cosmology formulated by
Heckmann agrees implicitly with Cartan's formulation of Newtonian mechanics as
geodesic motion in space-time, but does not unfold the underlying geometric
picture. I present the transformation theory of Newtonian mechanics and
gravity developed by Cartan and Heckmann, and show via coordinate
transformations that Heckmann's Newtonian cosmological model has a center, so
that the cosmological principle cannot hold globally.
  It is possible to confuse the relativity principle with a position of
relativism. Mach's principle has much to do with the latter and nothing to do
with the former. Both general relativity and nonlinear dynamics inform us that
most coordinate systems ae defined locally by differential equations that are
globally nonintegrable: global extensions of local coordinates usually do not
exist. I explain how defining inertial frames locally by free fall
short-circuits Mach's philosophic objectios to Newtonian dynamics.

</DOC>
<DOC>
<DOCNO> 102527 </DOCNO>
New Solvable Singular Potentials


  We obtain three new solvable, real, shape invariant potentials starting from
the harmonic oscillator, P\"oschl-Teller I and P\"oschl-Teller II potentials on
the half-axis and extending their domain to the full line, while taking special
care to regularize the inverse square singularity at the origin. The
regularization procedure gives rise to a delta-function behavior at the origin.
Our new systems possess underlying non-linear potential algebras, which can
also be used to determine their spectra analytically.

</DOC>
<DOC>
<DOCNO> 12418 </DOCNO>
Exact Phase Diagram of a model with Aggregation and Chipping


  We revisit a simple lattice model of aggregation in which masses diffuse and
coalesce upon contact with rate 1 and every nonzero mass chips off a single
unit of mass to a randomly chosen neighbour with rate $w$. The dynamics
conserves the average mass density $\rho$ and in the stationary state the
system undergoes a nonequilibrium phase transition in the $(\rho-w)$ plane
across a critical line $\rho_c(w)$. In this paper, we show analytically that in
arbitrary spatial dimensions, $\rho_c(w) = \sqrt{w+1}-1$ exactly and hence,
remarkably, independent of dimension. We also provide direct and indirect
numerical evidence that strongly suggest that the mean field asymptotic answer
for the single site mass distribution function and the associated critical
exponents are super-universal, i.e., independent of dimension.

</DOC>
<DOC>
<DOCNO> 84581 </DOCNO>
Gravitating BIon and BIon black hole with dilaton


  We construct static and spherically symmetric particle-like and black hole
solutions with magnetic or electric charge in the Einstein-Born-Infeld-dilaton
system, which is a generalization of the Einstein-Maxwell-dilaton (EMD) system
and of the Einstein-Born-Infeld (EBI) system. They have remarkable properties
which are not seen for the corresponding solutions in the EBI and the EMD
system.

</DOC>
<DOC>
<DOCNO> 118417 </DOCNO>
Star formation properties of UCM galaxies


  We present new near-infrared J and K imaging data for 67 galaxies from the
Universidad Complutense de Madrid survey used to determine the SFR density of
the local universe by Gallego et al. (1995). This is a sample of local
star-forming galaxies with redshift lower than 0.045, and they constitute a
representative subsample of the galaxies in the complete UCM survey. From the
new data, complemented with our own Gunn-r images and long-slit optical
spectroscopy, we have measured integrated K-band luminosities, r-J and J-K
colours, and Halpha luminosities and equivalent widths. Using a maximum
likelihood estimator and a complete set of evolutionary synthesis models, these
observations have allowed us to estimate the strength of the current (or most
recent) burst of star formation, its age, the star-formation rate and the total
stellar mass of the galaxies. An average galaxy in the sample has a stellar
mass of 5E10 Msun and is undergoing (or recently completed) a burst of star
formation involving about 2 per cent of its total stellar mass. We have
identified two separate classes of star-forming galaxies in the UCM sample: low
luminosity, high excitation galaxies (HII-like) and relatively luminous spirals
galaxies (starburst disk-like). The former show higher specific star formation
rates (SFR per unit mass) and burst strengths, and lower stellar masses than
the latter. With regard to their specific star formation rates, the UCM
galaxies are intermediate objects between normal quiescent spirals and the most
extreme HII galaxies.

</DOC>
<DOC>
<DOCNO> 12201 </DOCNO>
Wavepacket-current <--> supercurrent conversion in closed N/S/N circuits


  The rise and decay in space and time of a supercurrent in a superconductor
between two normal current leads connected to a reservoir is computed with the
help of quasiparticle wavepackets which suffer Andreev scattering in the
interfaces between the normal current leads and the superconductor. Stills from
a computer movie visualize electron <-> hole scattering and the creation and
destruction of the supercurrent.

</DOC>
<DOC>
<DOCNO> 117588 </DOCNO>
Dust in the 55 Cancri planetary system


  The presence of debris disks around $\sim$ 1-Gyr-old main sequence stars
suggests that an appreciable amount of dust may persist even in mature
planetary systems. Here we report the detection of dust emission from 55
Cancri, a star with one, or possibly two, planetary companions detected through
radial velocity measurements. Our observations at 850$\mu$m and 450$\mu$m imply
a dust mass of 0.0008-0.005 Earth masses, somewhat higher than that in the the
Kuiper Belt of our solar system. The estimated temperature of the dust grains
and a simple model fit both indicate a central disk hole of at least 10 AU in
radius. Thus, the region where the planets are detected is likely to be
significantly depleted of dust. Our results suggest that far-infrared and
sub-millimeter observations are powerful tools for probing the outer regions of
extrasolar planetary systems.

</DOC>
<DOC>
<DOCNO> 71630 </DOCNO>
Minimal electroweak symmetry breaking model in extra dimensions


  We show that if the Standard Model gauge fields and fermions propagate in
extra dimenions, a composite Higgs field with the correct quantum number can
arise naturally as a bound state due to the strong gauge interactions in higher
dimensions. The top quark mass and the Higgs mass can be predicted from the
infrared fixed points of the renormalization group equations. The top quark
mass is in good agreement with the experimental value, and the Higgs boson mass
is predicted to be ~200 GeV. There may be some other light bound states which
could be observed at upcoming collider experiments.

</DOC>
<DOC>
<DOCNO> 13958 </DOCNO>
Efficient tight-binding Monte Carlo structural sampling of complex


  While recent work towards the development of tight-binding and ab-initio
algorithms has focused on molecular dynamics, Monte Carlo methods can often
lead to better results with relatively little effort. We present here a
multi-step Monte Carlo algorithm that makes use of the possibility of quickly
evaluating local energies. For the thermalization of a 1000-atom configuration
of {\it a}-Si, this algorithm gains about an order of magnitude in speed over
standard molecular dynamics. The algorithm can easily be ported to a wide range
of materials and can be dynamically optimized for a maximum efficiency.

</DOC>
<DOC>
<DOCNO> 9690 </DOCNO>
Buckling of rods with spontaneous twist and curvature


  We analyze stability of a thin inextensible elastic rod which has
non-vanishing spontaneous generalized torsions in its stress-free state. Two
classical problems are studied, both involving spontaneously twisted rods: a
rectilinear beam compressed by axial forces, and a circular ring subjected to
uniform radial pressure on its outer perimeter. It is demonstrated that while
spontaneous twist stabilizes a rectilinear rod against buckling, its presence
has an opposite effect on a closed ring.

</DOC>
<DOC>
<DOCNO> 71380 </DOCNO>
First Lattice Calculation of the Electromagnetic Operator Amplitude


  We present the first lattice calculation of the matrix element of the
electromagnetic operator <pi0|Q+|K0>, where Q+ = (Q_d e/16 pi^2)* (\bar s_L
sigma{mu,nu} F{mu,nu} d_R + \bar s_R sigma{mu,nu} F{mu,nu} d_L). This matrix
element plays an important role, since it contributes to enhance the CP
violating part of the K_L -> pi0 e+ e- amplitude in supersymmetric extensions
of the Standard Model.

</DOC>
<DOC>
<DOCNO> 11179 </DOCNO>
A First-Principles Theory of Bloch Walls in Ferromagnets


  We present a first principles account of Bloch Walls on the basis of
relativistic Spin-Density Functional Theory in the Local Density Approximation
(LDA). We argue that calculations based on this description will provide useful
and novel informations about the physics of this important element of
micro-magnetics. To illustrate the points we wish to make we implement the
proposed calculations for Fe and determine the Bloch Wall thickness
$\ell_{BW}$. Moreover we study features of the electronic structure which arise
due to the presence of the Bloch Wall.

</DOC>
<DOC>
<DOCNO> 101604 </DOCNO>
Weak Limits of Riemannian Metrics in Surfaces with integral Curvature


  In this paper, we study the weak compactness of the set of conformal metrics
in any Riemann surface without boundary whose
 Calabi energy and area are uniformly bounded. We prove that for any sequence
of such metrics, there alwasy exists a subsequence which converges in
H\sp{2,2}_\sb{loc} everywhere except a finite number of bubble points. Blowup
analysis near bubble shows that the bubble on bubble phenomenon occurs. The
limit metric gives rise to a tree structure decomposition, where each node in
the tree represents a limit metric of a subsequence at that stage while the
edge of the tree structure represents the neck on the process of blowing up. We
also show that the number of the nodes which have more than three edges
attached is finite.

</DOC>
<DOC>
<DOCNO> 83494 </DOCNO>
Support for Debugging Automatically Parallelized Programs


  We describe a system that simplifies the process of debugging programs
produced by computer-aided parallelization tools. The system uses relative
debugging techniques to compare serial and parallel executions in order to show
where the computations begin to differ. If the original serial code is correct,
errors due to parallelization will be isolated by the comparison.
  One of the primary goals of the system is to minimize the effort required of
the user. To that end, the debugging system uses information produced by the
parallelization tool to drive the comparison process. In particular, the
debugging system relies on the parallelization tool to provide information
about where variables may have been modified and how arrays are distributed
across multiple processes. User effort is also reduced through the use of
dynamic instrumentation. This allows us to modify the program execution without
changing the way the user builds the executable.
  The use of dynamic instrumentation also permits us to compare the executions
in a fine-grained fashion and only involve the debugger when a difference has
been detected. This reduces the overhead of executing instrumentation.

</DOC>
<DOC>
<DOCNO> 151215 </DOCNO>
Rings of short N=3 superfields in three dimensions and M-theory on AdS_4


  In this paper we investigate three-dimensional superconformal gauge theories
with N=3 supersymmetry. Independently from specific models, we derive the
shortening conditions for unitary representations of the Osp(3|4) superalgebra
and we express them in terms of differential constraints on three dimensional
N=3 superfields. We find a ring structure underlying these short
representations, which is just the direct generalization of the chiral ring
structure of N=2 theories. When the superconformal field theory is realized on
the world-volume of an M2-brane such superfield ring is the counterpart of the
ring defined by the algebraic geometry of the 8-dimensional cone transverse to
the brane. This and other arguments identify the N=3 superconformal field
theory dual to M-theory compactified on AdS_4 x N^{0,1,0}. It is an N=3 gauge
theory with SU(N) x SU(N) gauge group coupled to a suitable set of
hypermultiplets, with an additional Chern Simons interaction. The AdS/CFT
correspondence can be directly verified using the recently worked out Kaluza
Klein spectrum of N^{0,1,0} and we find a perfect match. We also note that
besides the usual set of BPS conformal operators dual to the lightest KK
states, we find that the composite operators corresponding to certain massive
KK modes are organized into a massive spin 3/2 N=3 multiplet that might be
identified with the super-Higgs multiplet of a spontaneously broken N=4 theory.
We investigate this intriguing and inspiring feature in a separate paper.

</DOC>
<DOC>
<DOCNO> 67960 </DOCNO>
Evolution of thin-wall configurations of texture matter


  We consider the free matter of global textures within the framework of the
perfect fluid approximation in general relativity. We examine thermodynamical
properties of texture matter in comparison with radiation fluid and bubble
matter. Then we study dynamics of thin-wall selfgravitating texture objects,
and show that classical motion can be elliptical (finite), parabolical or
hyperbolical. It is shown that total gravitational mass of neutral textures in
equilibrium equals to zero as was expected. Finally, we perform the
Wheeler-DeWitt's minisuperspace quantization of the theory, obtain exact wave
functions and discrete spectra of bound states with provision for spatial
topology.

</DOC>
<DOC>
<DOCNO> 120309 </DOCNO>
X-ray spectral components in the hard state of GRS 1915+105: origin of


  We investigate the origin of the ubiquitous 0.5 - 10 Hz QPO in the Galactic
microquasar GRS 1915+105. Using the archival X-ray data from RXTE, we make a
wide band X-ray spectral fitting to the source during a low-hard state observed
in 1999 June. We resolve the X-ray spectra into three components, namely a
multi-color disk component, a Comptonised component and a power-law at higher
energies. This spectral description is favored compared to other normally used
spectra like a cut-off power law, hard components with reflection etc. We find
that the 0.5 - 10 Hz QPO is predominantly due to variations in the Comptonised
component. We use this result to constrain the location of the various spectral
components in the source.

</DOC>
<DOC>
<DOCNO> 102084 </DOCNO>
Kirkman's hypothesis revisited


  Watson proved Kirkman's hypothesis (partially solved by Cayley). Using
Lagrange Inversion, we drastically shorten Watson's computations and generalize
his results at the same time.

</DOC>
<DOC>
<DOCNO> 67681 </DOCNO>
String formation and chiral symmetry breaking in the heavy-light


  The effective quark Lagrangian is written for a light quark in the field of a
static antiquark, explicitly containing field correlators as coefficient
functions of products of quark operators. At large N_c the closed system of
equations for the gauge-invariant quark Green's function in the field of static
source is examined analytically. The formation of the string connecting the
light quark to the static source is observed numerically. The scalar Lorentz
nature of the resulting confinement is shown to hold for the considered case,
implying chiral symmetry breaking. The resulting spectrum with and without
perturbative gluon exchanges is obtained numerically and compared to the B and
D meson masses and HQET.

</DOC>
<DOC>
<DOCNO> 39824 </DOCNO>
Measurement of Inclusive Ds+- Photoproduction at HERA


  The first measurement of inclusive Ds+- photoproduction at HERA has been
performed with the ZEUS detector for photon-proton centre-of-mass energies 130
< W < 280 GeV. The measured cross section for 3 < pt(Ds) < 12 GeV and
|eta(Ds)|< 1.5 is sigma(ep -> Ds X) = 3.79 +- 0.59 (stat.) +0.26-0.46 (syst.)
+- 0.94 (br.) nb, where the last error arises from the uncertainty in the Ds
decay branching ratio. The measurements are compared with inclusive D*+-
photoproduction cross sections in the same kinematic region and with QCD
calculations. The Ds cross sections lie above a fixed-order next-to-leading
order calculation and agree better with a tree-level O(alpha,alpha_s^3)
calculation that was tuned to describe the ZEUS D* cross sections. The ratio of
Ds+- to D*+- cross sections is 0.41 +- 0.07 (stat.) +0.03-0.05 (syst.) +- 0.10
(br.). From this ratio, the strangeness-suppression factor in charm
photoproduction, within the LUND string fragmentation model, has been
calculated to be gamma_s = 0.27 +- 0.05 +- 0.07 (br.). The cross-section ratio
and gamma_s are in good agreement with those obtained in charm production in
e+e- annihilation.

</DOC>
<DOC>
<DOCNO> 102838 </DOCNO>
The moduli space of bilevel-6 abelian surfaces


  The moduli space of abelian surfaces with polarisation of type (1,6) and a
bilevel structure has positive Kodaira dimension. By contrast, Mukai has shown
that the moduli space of bilevel-t abelian sufaces is rational for t=2,3,4,5.

</DOC>
<DOC>
<DOCNO> 70551 </DOCNO>
K -> pi pi Phenomenology in the Presence of Electromagnetism


  We describe the influence of electromagnetism on the phenomenology of K -> pi
pi decays. This is required because the present data were analyzed without
inclusion of electromagnetic radiative corrections, and hence contain several
ambiguities and uncertainties which we describe in detail. Our presentation
includes a full description of the infrared effects needed for a new
experimental analysis. It also describes the general treatment of final state
interaction phases, needed because Watson's theorem is no longer valid in the
presence of electromagnetism. The phase of the isospin-two amplitude A_2 may be
modified by 50% -> 100%. We provide a tentative analysis using present data in
order to illustrate the sensitivity to electromagnetic effects, and also
discuss how the standard treatment of epsilon'/epsilon is modified.

</DOC>
<DOC>
<DOCNO> 118685 </DOCNO>
A Model for the Quiescent Phase of the Recurrent Nova U Scorpii


  A theoretical light curve is constructed for the quiescent phase of the
recurrent nova U Scorpii in order to resolve the existing distance discrepancy
between the outbursts (6 kpc) and the quiescences (14 kpc). Our U Sco model
consists of a very massive white dwarf (WD), an accretion disk (ACDK) with a
flaring-up rim, and a lobe-filling, slightly evolved, main-sequence star (MS).
The model properly includes an accretion luminosity of the WD, a viscous
luminosity of the ACDK, a reflection effect of the MS and the ACDK irradiated
by the WD photosphere. The B light curve is well reproduced by a model of 1.37
M_sun WD + 1.5 M_sun MS (0.8---2.0 M_sun MS is acceptable) with an ACDK having
a flaring-up rim, and the inclination angle i~80 degree. The calculated color
is rather blue (B-V~0.0) for a suggested mass accretion rate of 2.5 x 10^{-7}
M_sun yr^{-1}, thus indicating a large color excess of E(B-V)~0.56 with the
observational color of B-V=0.56 in quiescence. Such a large color excess
corresponds to an absorption of A_V~1.8 and A_B~2.3, which reduces the distance
to 6-8 kpc. This is in good agreement with the distance estimation of 4-6 kpc
for the latest outburst. Such a large intrinsic absorption is very consistent
with the recently detected period change of U Sco, which is indicating a mass
outflow of ~3 x 10^{-7} M_sun yr^{-1} through the outer Lagrangian points in
quiescence.

</DOC>
<DOC>
<DOCNO> 8714 </DOCNO>
Pre-K-Edge Structure on Anomalous X-Ray Scattering in LaMnO3


  We study the pre-K-edge structure of the resonant X-ray scattering for
forbidden reflections (anomalous scattering) in LaMnO3, using the band
calculation based on the local density approximation. We find a two-peak
structure with an intensity approximately 1/100 of that of the main peak. This
originates from a mixing of 4p states of Mn to 3d states of neighboring Mn
sites. The effect is enhanced by an interference with the tail of the main
peak. The effect of the quadrupole transition is found to be one order of
magnitude smaller than that of the dipole transition, modifying slightly the
azimuthal-angle dependence.

</DOC>
<DOC>
<DOCNO> 119502 </DOCNO>
How Do We See the Nuclear Region (r < 0.1 pc) of Narrow-Line Seyfert 1


  We propose two statistical tests to investigate how we see the nuclear region
(r < 0.1 pc) of Narrow-Line Seyfert 1 galaxies (NLS1s). 1) The high-ionization
nuclear emission-line region (HINER) test: Seyfert 1 galaxies (S1s) have
systematically higher flux ratios of [Fe VII] lambda 6087 to [O III] lambda
5007 than Seyfert 2 galaxies (S2s). This is interpreted in that a significant
part of the [Fe VII] lambda 6087 emission arises from the inner walls of dusty
tori that cannot be seen in S2s (Murayama & Taniguchi 1998a,b). 2) The
mid-infrared test: S1s have systematically higher flux ratios of the L band
(3.5 micrometer) to the IRAS 25 micrometer band than S2s. This is also
interpreted in that a significant part of the L band emission arises from the
inner walls of dusty tori, because the tori are optically thick enough to
absorb the L band emission if the tori are viewed nearly edge on (Murayama et
al. 2000). Applying these tests to a sample of NLS1s, we have found that the
NLS1s possibly have nearly the same properties as S1s.

</DOC>
<DOC>
<DOCNO> 150459 </DOCNO>
Automorphisms, Non-linear Realizations and Branes


  The theory of non-linear realizations is used to derive the dynamics of the
branes of M theory. A crucial step in this procedure is to use the enlarged
automorphism group of the supersymmetry algebra recently introduced. The field
strengths of the worldvolume gauge fields arise as some of the Goldstone fields
associated with this automorphism group. The relationship to the superembedding
approach is given.

</DOC>
<DOC>
<DOCNO> 101884 </DOCNO>
The Marcinkiewicz multiplier condition for bilinear operators


  This article is concerned with the question of whether Marcinkiewicz
multipliers on $\mathbb R^{2n}$ give rise to bilinear multipliers on $\mathbb
R^n\times \mathbb R^n$. We show that this is not always the case. Moreover we
find necessary and sufficient conditions for such bilinear multipliers to be
bounded. These conditions in particular imply that a slight logarithmic
modification of the Marcinkiewicz condition gives multipliers for which the
corresponding bilinear operators are bounded on products of Lebesgue and Hardy
spaces.

</DOC>
<DOC>
<DOCNO> 99326 </DOCNO>
A Probabilistic Proof of the Rogers Ramanujan Identities


  The asymptotic probability theory of conjugacy classes of the finite general
linear and unitary groups leads to a probability measure on the set of all
partitions of natural numbers. A simple method of understanding these measures
in terms of Markov chains is given and compared with work on the uniform
measure. Elementary probabilistic proofs of the Rogers-Ramanujan identities
follow. As a corollary, the main case of Bailey's lemma is interpreted as
finding eigenvectors of the transition matrix of the Markov chain. It is shown
that the viewpoint of Markov chains extends to quivers.

</DOC>
<DOC>
<DOCNO> 117378 </DOCNO>
The Hamburg/SAO Survey for Emission-Line Galaxies. III. The Third List


  We present the third list with results {Tables 2 to 6 are available only in
electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr
(130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html. Figures A1 to
A9 will be made available only in the electronic version of the journal.} of
the Hamburg/SAO Survey for Emission-Line Galaxies (HSS therein, SAO - Special
Astrophysical Observatory, Russia). This survey is based on the digitized
objective-prism photoplate database of the Hamburg Quasar Survey (HQS).
  Here, we present new spectroscopic results of candidates which were obtained
in 1998 with the 2.1 m KPNO and the 2.2 m Calar Alto telescopes. All candidates
are selected in the declination band +35$^{\circ}$ to +40$^{\circ}$.
  The follow-up spectroscopy with the 2 m class telescopes confirmed 85
emission-line objects out of 113 observed candidates and allowed their
quantitative spectral classification. For 80 of them, the redshifts are
determined for the first time. For 5 previously known ELGs, line ratios are
presented for the first time. We could classify 55 out of the 85 emission-line
objects as BCG/H{\sc ii} galaxies or probable BCGs, 4 - as QSOs, 6 - as Seyfert
galaxies, 1 - as super-association in a subluminous spiral galaxy, and 11 are
low-excitation objects - either starburst nuclear (SBN), or dwarf amorphous
nuclear starburst galaxies (DANS). We could not classify 8 ELGs. Further, for 8
more galaxies we did not detect any significant emission lines.

</DOC>
<DOC>
<DOCNO> 150391 </DOCNO>
A Note on Open Strings in the Presence of Constant B-Field


  We consider the open string sigma-model in the presence of a constant
Neveu-Schwarz B-field on the world-sheet that is topologically equivalent to a
disk with n holes. First, we compute the sigma-model partition function.
Second, we make a consistency check of ideas about the appearance of
noncommutative geometry within open strings.

</DOC>
<DOC>
<DOCNO> 8313 </DOCNO>
Comment on "Relativistic Effects of Light in Moving Media with Extremely


  In [cond-mat/9906332; Phys. Rev. Lett. 84, 822 (2000)] and [physics/9906038;
Phys. Rev. A 60, 4301 (1999)] Leonhardt and Piwnicki have presented an
interesting analysis of how to use a flowing dielectric fluid to generate a
so-called "optical black hole". Qualitatively similar phenomena using
acoustical processes have also been much investigated. Unfortunately there is a
subtle misinterpretation in the Leonhardt-Piwnicki analysis regarding these
"optical black holes": While it is clear that "optical black holes" can
certainly exist as theoretical constructs, and while the experimental prospects
for actually building them in the laboratory are excellent, the particular
model geometries that Leonhardt and Piwnicki write down as alleged examples of
"optical black holes" are in fact not black holes at all.

</DOC>
<DOC>
<DOCNO> 121984 </DOCNO>
Photon Splitting and Pair Creation in Highly Magnetized Pulsars


  The absence of radio pulsars with long periods has lead to the popular notion
of a high P ``death line.'' In the standard picture, beyond this boundary,
pulsars with low spin rates cannot accelerate particles above the stellar
surface to high enough energies to initiate pair cascades, and the pair
creation needed for radio emission is strongly suppressed. In this paper we
explore the possibility of another pulsar ``death line'' in the context of
polar cap models, corresponding to high magnetic fields B in the upper portion
of the period-period derivative diagram, a domain where few radio pulsars are
observed. The origin of this high B boundary, which may occur when B becomes
comparable to or exceeds $B_{\rm cr} = 4.4 \times 10^{13}$ Gauss, is also due
to the suppression of magnetic pair creation, but primarily because of
ineffective competition with magnetic photon splitting. Threshold pair creation
also plays a prominent role in the suppression of cascades. We present Monte
Carlo calculations of the pair yields in photon splitting/pair cascades which
show that, in the absence of scattering effects, pair production is effectively
suppressed, but only if all three modes of photon splitting allowed by QED are
operating in high fields. This paper describes the probable shape and position
of the new ``death line,'' above which pulsars are expected to be radio quiet,
but perhaps still X-ray and gamma-ray bright. The hypothesized existence of
radio-quiet sources finds dramatic support in the recent discovery of
ultra-strong fields in Soft Gamma-ray Repeaters and Anomalous X-ray Pulsars.
Guidelines for moderate to high B pulsar searches at radio wavelengths and also
in the soft and hard gamma-ray bands are presented.

</DOC>
<DOC>
<DOCNO> 169771 </DOCNO>
Consistent histories, the quantum Zeno effect, and time of arrival


  We present a decomposition of the general quantum mechanical evolution
operator, that corresponds to the path decomposition expansion, and interpret
its constituents in terms of the quantum Zeno effect (QZE). This decomposition
is applied to a finite dimensional example and to the case of a free particle
in the real line, where the possibility of boundary conditions more general
than those hitherto considered in the literature is shown. We reinterpret the
assignment of consistent probabilities to different regions of spacetime in
terms of the QZE. The comparison of the approach of consistent histories to the
problem of time of arrival with the solution provided by the probability
distribution of Kijowski shows the strength of the latter point of view.

</DOC>
<DOC>
<DOCNO> 101416 </DOCNO>
Spectral Theory of Pseudo-Ergodic Operators


  We define a class of pseudo-ergodic non-self-adjoint Schr\"odinger operators
acting in spaces $l^2(X)$ and prove some general theorems about their spectral
properties. We then apply these to study the spectrum of a non-self-adjoint
Anderson model acting on $l^2(\Z)$, and find the precise condition for 0 to lie
in the spectrum of the operator. We also introduce the notion of localized
spectrum for such operators.

</DOC>
<DOC>
<DOCNO> 85499 </DOCNO>
Quantum correlation functions and the classical limit


  We study the transition from the full quantum mechanical description of
physical systems to an approximate classical stochastic one. Our main tool is
the identification of the closed-time-path (CTP) generating functional of
Schwinger and Keldysh with the decoherence functional of the consistent
histories approach. Given a degree of coarse-graining in which interferences
are negligible, we can explicitly write a generating functional for the
effective stochastic process in terms of the CTP generating functional. This
construction gives particularly simple results for Gaussian processes. The
formalism is applied to simple quantum systems, quantum Brownian motion,
quantum fields in curved spacetime. Perturbation theory is also explained. We
conclude with a discussion on the problem of backreaction of quantum fields in
spacetime geometry.

</DOC>
<DOC>
<DOCNO> 71108 </DOCNO>
Elastic and radiative pi^+p scattering and properties of the Delta^{++}


  We study the Delta^{++} contributions to elastic and radiative \pi^+p
scattering within an effective Lagrangian model which incorporates the Delta,
N, rho and sigma meson degrees of freedom. This model provides a description of
the Delta resonance and its interactions that respects electromagnetic gauge
invariance and invariance under contact transformations when finite width
effects are incorporated. Following recent developments in the description of
unstable gauge bosons, we use a complex mass scheme to introduce the finite
width of the Delta^{++} without spoiling gauge invariance. The total cross
section of elastic \pi^+p scattering, whose amplitude exhibits the resonant
plus background structure of S-matrix theory, is used to fix the mass, width
and strong coupling of the \Delta resonance. The differential cross section of
elastic scattering is found in very good agreement with experimental data. The
magnetic dipole moment of the Delta^{++}, \mu_{Delta}, is left as the only
adjustable parameter in radiative \pi^+p scattering. From a fit to the most
sensitive configurations for photon emission in this process, we obtain
\mu_{\Delta} = (6.14 +-0.51)e/2m_p, in agreement with predictions based on the
SU(6) quark model.

</DOC>
<DOC>
<DOCNO> 10494 </DOCNO>
Magnetic Phase Diagram and Metal-Insulator Transition of NiS2-xSex


  Magnetic phase diagram of NiS2-xSex has been reexamined by systematic studies
of electrical resistivity, uniform magnetic susceptibility and neutron
diffraction using single crystals grown by a chemical transport method. The
electrical resistivity and the uniform magnetic susceptibility exhibit the same
feature of temperature dependence over a wide Se concentration. A distinct
first order metal-insulator (M-I) transition accompanied by a volume change was
observed only in the antiferromagnetic ordered phase for 0.50<x<0.59. In this
region, the M-I transition makes substantial effects to the thermal evolution
of staggered moments. In the paramagnetic phase, the M-I transition becomes
broad; both the electrical resistivity and the uniform magnetic susceptibility
exhibit a broad maximum around the temperatures on the M-I transition-line
extrapolated to the paramagnetic phase.

</DOC>
<DOC>
<DOCNO> 100722 </DOCNO>
Bicartesian Coherence


  Coherence is demonstrated for categories with binary products and sums, but
without the terminal and the initial object, and without distribution. This
coherence amounts to the existence of a faithful functor from a free category
with binary products and sums to the category of relations on finite ordinals.
This result is obtained with the help of proof-theoretic normalizing
techniques. When the terminal object is present, coherence may still be proved
if of binary sums we keep just their bifunctorial properties. It is found that
with the simplest understanding of coherence this is the best one can hope for
in bicartesian categories. The coherence for categories with binary products
and sums provides an easy decision procedure for equality of arrows. It is also
used to demonstrate that the categories in question are maximal, in the sense
that in any such category that is not a preorder all the equations between
arrows involving only binary products and sums are the same. This shows that
the usual notion of equivalence of proofs in nondistributive
conjunctive-disjunctive logic is optimally defined: further assumptions would
make this notion collapse into triviality.

</DOC>
<DOC>
<DOCNO> 122564 </DOCNO>
Lead: Asymptotic Giant Branch production and Galactic Chemical Evolution


  The enrichment of Pb in the Galaxy is followed in the framework of a detailed
model of Galactic chemical evolution that already proved adequate to reproduce
the chemical enrichment of O and of the elements from Ba to Eu. The stellar
yields are computed through nucleosynthesis calculations in the Asymptotic
Giant Branch (AGB) phase of low- and intermediate-mass stars, covering a wide
range of metallicities. The physical parameters of the stellar structure were
derived from full stellar evolutionary models previously computed. We show that
low-mass AGB stars are the main producers of Pb in the Galaxy, with a complex
dependence on metallicity and a maximum efficiency at [Fe/H] ~ -1. Our
calculations succeed in reproducing the abundances of Pb isotopes in the solar
system: the role attributed by the classical analysis of the s-process to the
'strong component', in order to explain more than 50% of solar 208Pb, is
actually played by the high production of Pb in low-mass and low-metallicity
AGB stars. We then follow the Galactic chemical evolution of Pb isotopes and
give our expectations on the s-process contribution to each of them at the
epoch of the solar system formation. Finally, we present new spectroscopic
estimates of Pb abundance on a sample of field stars and compare them, together
with a few other determinations available, with the predicted trend of [Pb/Fe]
in the Galaxy.

</DOC>
<DOC>
<DOCNO> 178721 </DOCNO>
New method for measuring azimuthal distributions in nucleus-nucleus


  The methods currently used to measure azimuthal distributions of particles in
heavy ion collisions assume that all azimuthal correlations between particles
result from their correlation with the reaction plane. However, other
correlations exist, and it is safe to neglect them only if azimuthal
anisotropies are much larger than 1/sqrt(N), with N the total number of
particles emitted in the collision. This condition is not satisfied at
ultrarelativistic energies. We propose a new method, based on a cumulant
expansion of multiparticle azimuthal correlations, which allows to measure much
smaller values of azimuthal anisotropies, down to 1/N. It is simple to
implement and can be used to measure both integrated and differential flow.
Furthermore, this method automatically eliminates the major systematic errors,
which are due to azimuthal asymmetries in the detector acceptance.

</DOC>
<DOC>
<DOCNO> 12096 </DOCNO>
Swelling and Dissolution of onion phases: The effect of temperature


  Contact experiments have been performed between an onion lamellar phase and
brine, in the SDS/octanol/brine system. Using video microscopy we have studied
the nonequilibrium behaviour of the swelling and dissolution process of onions.
Experiments at T=20degC and 30degC showed that temperature has a strong effect
on their bahaviour. At low temperature onions are observed to diffuse away from
the onion phase and only swell slightly. However by increasing the temperature
we induce the formation of the sponge phase at the onion/brine interface.
Onions that initailly swell then dissolve into sponge phase expel a stable core
which moves to the micellar phase and remains stable there. Over a longer
period of time (several days) we have also observed coalescence leading to the
formation of large onions of up to 100microns in diameter. These huge onions
have a radial distribution of domains, or solvent cavities, within them.

</DOC>
<DOC>
<DOCNO> 11709 </DOCNO>
Orientation of Vortices in a Superconducting Thin-Film: Quantitative


  We present a quantitative comparison of the magnetization measured by
spin-polarized neutron reflectivity (SPNR) and DC magnetometry on a 1370 \AA\
-thick Nb superconducting film. As a function of magnetic field applied in the
film plane, SPNR exhibits reversible behavior whereas the DC magnetization
shows substantial hysteresis. The difference between these measurements is
attributed to a rotation of vortex magnetic field out of the film plane as the
applied field is reduced. Since SPNR measures only the magnetization parallel
to the film plane whereas DC magnetization is strongly influenced by the
perpendicular component of magnetization when there is a slight sample tilt,
combining the two techniques allows one to distinguish two components of
magnetization in a thin film.

</DOC>
<DOC>
<DOCNO> 100332 </DOCNO>
Graphs of groups and the Atiyah conjecture for one-relator groups


  Paper withdrawn because of a gap in the proof of Proposition 3 of Thomas
Schick: "Integrality of L2-Betti numbers", Math. Ann. 317, 727-750
(arXiv.org/abs/math.gt/0001101). Most results of the withdrawn paper were based
on this proposition.

</DOC>
<DOC>
<DOCNO> 84984 </DOCNO>
Dynamics of Rotating Cylindrical Shells in General Relativity


  Cylindrical spacetimes with rotation are studied using the Newmann-Penrose
formulas. By studying null geodesic deviations the physical meaning of each
component of the Riemann tensor is given. These spacetimes are further extended
to include rotating dynamic shells, and the general expression of the surface
energy-momentum tensor of the shells is given in terms of the discontinuation
of the first derivatives of the metric coefficients. As an application of the
developed formulas, a stationary shell that generates the Lewis solutions,
which represent the most general vacuum cylindrical solutions of the Einstein
field equations with rotation, is studied by assuming that the spacetime inside
the shell is flat. It is shown that the shell can satisfy all the energy
conditions by properly choosing the parameters appearing in the model, provided
that $ 0 \le \sigma \le 1$, where $\sigma$ is related to the mass per unit
length of the shell.

</DOC>
<DOC>
<DOCNO> 99554 </DOCNO>
Higher limits via subgroup complexes


  We study the higher derived functors of the inverse limit of a functor F: D
--> Z_{(p)}-mod, where D is one of the standard categories which arise when
studying the homotopy theory of the classifying space of a finite group G,
e.g., the orbit category or the Quillen category of G. These higher limits are
of importance e.g., for the study of maps between classifying spaces as well as
for group cohomology.
  We show that these higher limits can be identified with the G-equivariant
Bredon cohomology of the subgroup complex of p-subgroups in G (i.e., the nerve
of the poset of p-subgroups in G) with values in a G-local coefficient system.
We examine when smaller complexes can be used e.g., taking only p-radical
subgroups, p-centric subgroups, elementary abelian p-subgroups or various
subcollections thereof.
  Since the subgroup complexes are finite complexes, and often rather small,
this provides concrete, computable formulas for these higher limits,
generalizing earlier work of especially Jackowski-McClure-Oliver.
  As an application we look at the special case where all the higher limits
vanish, as for example is the case for group cohomology. If F is a functor on
the orbit category our formulas for the higher limits in this case yield five
different expressions of F(G) in terms of values of F on proper subgroups. Two
of these are `classical' namely Webb's exact sequence of Mackey functors and a
formula for calculating stable elements, previously obtained using Alperin's
fusion theorem. Examining this case also leads to improvements of sharpness
results of homology decompositions due to Dwyer and others.

</DOC>
<DOC>
<DOCNO> 150533 </DOCNO>
Extended Conformal Symmetry


  We show that the grading of fields by conformal weight, when built into the
initial group symmetry, provides a discrete, non-central conformal extension of
any group containing dilatations. We find a faithful vector representation of
the extended conformal group and show that it has a scale-invariant scalar
product and satisfies a closed commutator algebra. The commutator algebra
contains the infinite Heisenberg and Virasoro algebras. In contrast to the
classical treatment of scale invariance, covariant derivatives and gauge
transformations automatically incorporate the correct conformal weights when
the extended symmetry is gauged.

</DOC>
<DOC>
<DOCNO> 10882 </DOCNO>
Force fluctuation in a driven elastic chain


  We study the dynamics of an elastic chain driven on a disordered substrate
and analyze numerically the statistics of force fluctuations at the depinning
transition. The probability distribution function of the amplitude of the slip
events for small velocities is a power law with an exponent $+AFw-tau$
depending on the driving velocity. This result is in qualitative agreement with
experimental measurements performed on sliding elastic surfaces with
macroscopic asperities. We explore the properties of the depinning transition
as a function of the driving mode (i.e. constant force or constant velocity)
and compute the force-velocity diagram using finite size scaling methods. The
scaling exponents are in excellent agreement with the values expected in
interface models and, contrary to previous studies, we found no difference in
the exponents for periodic and disordered chains.

</DOC>
<DOC>
<DOCNO> 118660 </DOCNO>
Smoke Signals From IRC +10216: 1. Milliarcsecond Proper Motions of the


  The results of a 7-epoch interferometric imaging study, at wavelengths in the
near-infrared K-band, of the carbon star IRC +10216 are presented. The use of
non- and partially-redundant aperture masking techniques on the 10-m Keck-I
telescope has allowed us to produce images of the innermost regions of the
circumstellar dust envelope with unprecedented detail. With roughly twice the
resolving power of previous work, the complex asymmetric structures reported
within the central 0.5 arcsec (20 stellar radii) have been imaged at the size
scale of the stellar disk itself (about 50 mas). A prominent dark lane at a
position angle of approximately 120 deg is suggested to be an optically thick
disk or torus of dust which could help to explain IRC +10216's well-known
bipolarity at a position angle of 20 deg. Observations spanning more than a
pulsational cycle (638 days) have revealed significant temporal evolution of
the nebula, including the outward motion of bright knots and clumps.
Registering these displacements against the compact bright core, which we
tentatively identify as marking the location of the star, has allowed us to
determine the apparent angular velocity at a number of points. The magnitudes
of the proper motions were found to be in agreement with current estimates of
the stellar distance and radial velocity. Higher outflow speeds were found for
features with greater separation from the core. This is consistent with
acceleration taking place over the region sampled by the measurements, however
alternate interpretations are also presented. Although a number of changes of
morphology were found, none were clearly interpreted as the condensation of new
dust over the pulsation cycle.

</DOC>
<DOC>
<DOCNO> 101388 </DOCNO>
Limit canonical systems on curves with two components


  In the 80's D. Eisenbud and J. Harris considered the following problem:
``What are the limits of Weierstrass points in families of curves degenerating
to stable curves?'' But for the case of stable curves of compact type, treated
by them, this problem remained wide open since then. In the present article, we
propose a concrete approach to this problem, and give a quite explicit solution
for stable curves with just two irreducible components meeting at points in
general position.

</DOC>
<DOC>
<DOCNO> 13539 </DOCNO>
Resonances in one and two rows of triangular Josephson junction cells


  We present an experimental and analytical study of resonances in the
current-voltage characteristics of single and double row triangular Josephson
arrays. The magnetic field dependences of the voltage positions of the
resonances have been measured for various cell inductances and junction
critical currents. In double row arrays, we have observed a peculiar resonance,
whose voltage position decreases with magnetic field. We derive the spectrum of
linear electromagnetic waves propagating in the arrays. In the double row
array, the spectrum consists of many branches that differ by the behavior of
the Josephson junctions transverse to the bias current direction. The measured
magnetic field dependence of the resonance voltages is mapped to the linear
mode spectrum and good agreement between experiments and model is found.

</DOC>
<DOC>
<DOCNO> 151267 </DOCNO>
The transformations of non-abelian gauge fields under translations


  I consider infinitesimal translations $x'^{\alpha}=x^{\alpha}+\delta
x^{\alpha}$ and demand that Noether's approach gives a symmetric
energy-momentum tensor as it is required for gravitational sources. This
argument determines the transformations of non-abelian gauge fields under
infinitesimal translations to differ from the usually assumed invariance by the
gauge transformation, $A'^a_{\gamma} (x') - A^a_{\gamma}(x) = \partial_{\gamma}
[ \delta x_{\beta} A^{a \beta}(x)] + C^a_{bc} \delta x_{\beta} A^{c \beta}(x)
A^{b}_{\gamma}(x)$ where the $C^a_{bc}$ are the structure constants of the
gauge group.

</DOC>
<DOC>
<DOCNO> 12212 </DOCNO>
Josephson Plasma Resonance in Solid and Glass Phases of


  Vortex matter phases and phase transitions are investigated by means of
Josephson plasma resonance in under-doped Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$
single crystals in a microwave frequency range between 19 and 70 GHz.
Accompanied by the vortex lattice melting transition, a jump of the interlayer
phase coherence extracted from the field dependence of the plasma frequency was
observed. In the solid phase, the interlayer coherence little depends on field
at a temperature region well below $T_c$ while it gradually decreases as field
increases toward the melting line up to just below $T_c$. As a result, the
magnitude of the jump decreases with increasing temperature and is gradually
lost in the vicinity of $T_c$. This indicates that the vortex lines formed in
the vortex solid phase are thermally meandering and the phase transition
becomes weak especially just below $T_c$.

</DOC>
<DOC>
<DOCNO> 99767 </DOCNO>
Divergence operators and odd Poisson brackets


  We define the divergence operators on a graded algebra, and we show that,
given an odd Poisson bracket on the algebra, the operator that maps an element
to the divergence of the hamiltonian derivation that it defines is a generator
of the bracket. This is the ``odd laplacian'', $\Delta$, of Batalin-Vilkovisky
quantization. We then study the generators of odd Poisson brackets on
supermanifolds, where divergences of graded vector fields can be defined either
in terms of berezinian volumes or of graded connections. Examples include
generators of the Schouten bracket of multivectors on a manifold (the
supermanifold being the cotangent bundle where the coordinates in the fibres
are odd) and generators of the Koszul-Schouten bracket of forms on a Poisson
manifold (the supermanifold being the tangent bundle, with odd coordinates on
the fibres).

</DOC>
<DOC>
<DOCNO> 116236 </DOCNO>
Why Occam's Razor


  In this paper, I show why in an ensemble theory of the universe, we should be
inhabiting one of the elements of that ensemble with least information content
that satisfies the anthropic principle. This explains the effectiveness of
aesthetic principles such as Occam's razor in predicting usefulness of
scientific theories. I also show, with a couple of reasonable assumptions about
the phenomenon of consciousness, that quantum mechanics is the most general
{\em linear} theory satisfying the anthropic principle.

</DOC>
<DOC>
<DOCNO> 150885 </DOCNO>
Quasinormal modes of Reissner-Nordstr$\ddot{o}$m Anti-de Sitter Black


  Complex frequencies associated with quasinormal modes for large
Reissner-Nordstr$\ddot{o}$m Anti-de Sitter black holes have been computed.
These frequencies have close relation to the black hole charge and do not
linearly scale with the black hole temperature as in Schwarzschild Anti-de
Sitter case. In terms of AdS/CFT correspondence, we found that the bigger the
black hole charge is, the quicker for the approach to thermal equilibrium in
the CFT. The properties of quasinormal modes for $l>0$ have also been studied.

</DOC>
<DOC>
<DOCNO> 120053 </DOCNO>
Properties of observed Ly-$\alpha$ forest


  The main observed properties of Ly-$\alpha$ absorbers are investigated on the
basis of theoretical model of formation and evolution of DM structure elements.
This model is generally consistent with simulations of absorbers formation and
with statistical description of structure evolution based on the Zel'dovich
theory. The analysis of redshift variations of comoving linear number density
of absorbers was performed in our previous paper.
  We show that the observed characteristics of Doppler parameter can be related
to the size of DM structure elements what allows us to explain the observed
distribution of Doppler parameter. This distribution is found to be consistent
with the Gaussian initial perturbations. The observed characteristics of
entropy and column density, $N_{HI}$, confirm that merging of pancakes is the
main evolutionary process at redshifts $z\geq 2$. The observed sample of
absorbers characterizes mainly the matter distribution within large low density
regions and therefore it is difficult to reconstruct the density field from the
distribution of absorbers.

</DOC>
<DOC>
<DOCNO> 84740 </DOCNO>
Action of Singular Instantons of Hawking-Turok Type


  Using Kaluza-Klein technique we show that the singularity of Hawking-Turok
type has a fixed point (bolt) contribution to the action in addition to the
usual boundary contribution. Interestingly by adding this contribution we can
obtain a simple expression for the total action which is feasible for both
regular and singular instantons. Our result casts doubt on the constraint
proposed by Turok in the recent calculation in which Vilenkin's instantons are
regarded as a limit of certain constrained instantons.

</DOC>
<DOC>
<DOCNO> 150569 </DOCNO>
Dressing Symmetries of Holomorphic BF Theories


  We consider holomorphic BF theories, their solutions and symmetries. The
equivalence of Cech and Dolbeault descriptions of holomorphic bundles is used
to develop a method for calculating hidden (nonlocal) symmetries of holomorphic
BF theories. A special cohomological symmetry group and its action on the
solution space are described.

</DOC>
<DOC>
<DOCNO> 70094 </DOCNO>
Back-Reaction In Lightcone QED


  We consider the back-reaction of quantum electrodynamics upon an electric
field E(x_+) = - A'_-(x_+) which is parallel to x^3 and depends only on the
lightcone coordinate x_+ = (x^0 + x^3)/\sqrt{2}. Novel features are that the
mode functions have simple expressions for arbitrary A_-(x_+), and that one
cannot ignore the usual lightcone ambiguity at zero + momentum. Each mode of
definite canonical momenta k_+ experiences pair creation at the instant when
its kinetic momentum p_+=k_+ - e A_-(x_+) vanishes, at which point operators
from the surface at x_- =-\infty play a crucial role. Our formalism permits a
more explicit and complete derivation of the rate of particle production than
is usually given. We show that the system can be understood as the infinite
boost limit of the analogous problem of an electric field which is homogeneous
on surfaces of constant x^0.

</DOC>
<DOC>
<DOCNO> 178820 </DOCNO>
Pseudo SU(3) shell model: Normal parity bands in odd-mass nuclei


  A pseudo shell SU(3) model description of normal parity bands in 159-Tb is
presented. The Hamiltonian includes spherical Nilsson single-particle energies,
the quadrupole-quadrupole and pairing interactions, as well as three rotor
terms. A systematic parametrization is introduced, accompained by a detailed
discussion of the effect each term in the Hamiltonian has on the energy
spectrum. Yrast and excited band wavefunctions are analyzed together with their
B(E2) values.

</DOC>
<DOC>
<DOCNO> 40668 </DOCNO>
Direct probes of R-parity-violating supersymmetric couplings via


  We study the s-channel production of a single top squark in hadron collisions
through an R-parity-violating mechanism, examining in detail the case in which
the squark decays through an R-parity-conserving process into a bottom quark, a
lepton, and missing energy. We show that the top squark can be discovered if
its mass is less than 400 GeV, or that the current bound on the size of the
R-parity-violating couplings can be reduced by up to one order of magnitude
with existing data and by two orders of magnitude at the forthcoming run II of
the Fermilab Tevatron.

</DOC>
<DOC>
<DOCNO> 151008 </DOCNO>
Non-Relativistic Non-Commutative Field Theory and UV/IR Mixing


  We study a non-commutative non-relativistic scalar field theory in 2+1
dimensions. The theory shows the UV/IR mixing typical of QFT on non-commutative
spaces. The one-loop correction to the two-point function turns out to be given
by a delta-function in momentum space. The one-loop correction to the
four-point function is of logarithmic type. We also evaluate the thermodynamic
potential at two-loop order. To avoid an IR-singularity we have to introduce a
chemical potential. The suppression of the non-planar contribution with respect
to the planar one turns out to depend crucially on the value of the chemical
potential.

</DOC>
<DOC>
<DOCNO> 122993 </DOCNO>
Fractal Structure in Galactic Star Fields


  The fractal structure of star formation on large scales in disk galaxies is
studied using the size distribution function of stellar aggregates in kpc-scale
star fields. Achival HST images of 10 galaxies are Gaussian smoothed to define
the aggregates, and a count of these aggregates versus smoothing scale gives
the fractal dimension. Fractal and Poisson models confirm the procedure. The
fractal dimension of star formation in all of the galaxies is ~2.3. This is the
same as the fractal dimension of interstellar gas in the Milky Way and nearby
galaxies, suggesting that star formation is a passive tracer of gas structure
defined by self-gravity and turbulence. Dense clusters like the Pleiades form
at the bottom of the hierarchy of structures, where the protostellar gas is
densest. If most stars form in such clusters, then the fractal arises from the
spatial distribution of their positions, giving dispersed star fields from
continuous cluster disruption. Dense clusters should have an upper mass limit
that increases with pressure, from ~1000 Msun in regions like the Solar
neighborhood to one million Msun in starbursts.

</DOC>
<DOC>
<DOCNO> 150353 </DOCNO>
Brane-Antibrane Constructions


  In type II string theories, we examine intersecting brane constructions
containing brane-antibrane pairs suspended between 5-branes, and more general
non-BPS constructions. The tree-level spectra are obtained in each case. We
identify various models with distinct physics: parallel brane-antibrane pairs,
adjacent pairs, non-adjacent pairs, and configurations which break all
supersymmetry even though any pair of branes preserves some supersymmetry. In
each case we examine the possible decay modes. Some of these configurations
turn out to be tachyon-free, stable non-BPS states. We use T-duality to map
some of our brane constructions to brane-antibrane pairs at ALE singularities.
This enables us to explicitly derive the spectra by the analogue of the quiver
construction, and to compute the sign of the brane-antibrane force in each
case.

</DOC>
<DOC>
<DOCNO> 99643 </DOCNO>
Universality and scaling of zeros on symplectic manifolds


  This article is concerned with random holomorphic polynomials and their
generalizations to algebraic and symplectic geometry. A natural
algebro-geometric generalization studied in our prior work involves random
holomorphic sections $H^0(M,L^N)$ of the powers of any positive line bundle $L
\to M$ over any complex manifold. Our main interest is in the statistics of
zeros of $k$ independent sections (generalized polynomials) of degree $N$ as
$N\to\infty$. We fix a point $P$ and focus on the ball of radius $1/\sqrt{N}$
about $P$. Under a microscope magnifying the ball by the factor $\sqrt{N}$, the
statistics of the configurations of simultaneous zeros of random $k$-tuples of
sections tends to a universal limit independent of $P,M,L$. We review this
result and generalize it further to the case of pre-quantum line bundles over
almost-complex symplectic manifolds $(M,J,\omega)$. Following [SZ2], we replace
$H^0(M,L^N)$ in the complex case with the `asymptotically holomorphic' sections
defined by Boutet de Monvel-Guillemin and (from another point of view) by
Donaldson and Auroux. Using a generalization to an $m$-dimensional setting of
the Kac-Rice formula for zero correlations together with the results of [SZ2],
we prove that the scaling limits of the correlation functions for zeros of
random $k$-tuples of asymptotically holomorphic sections belong to the same
universality class as in the complex case.

</DOC>
<DOC>
<DOCNO> 170135 </DOCNO>
New hydrogen-like potentials


  Using the modified factorization method introduced by Mielnik, we construct a
new class of radial potentials whose spectrum for l=0 coincides exactly with
that of the hydrogen atom. A limiting case of our family coincides with the
potentials previously derived by Abraham and Moses

</DOC>
<DOC>
<DOCNO> 70811 </DOCNO>
Absence of higher order corrections to the non-Abelian Chern-Simons


  We extend the Coleman-Hill analysis to non-Abelian Chern-Simons theories
containing a tree level topological mass term. We show, in the case of a pure
Yang-Mills-Chern-Simons theory, that there are no corrections to the
coefficient of the Chern-Simons term beyond one loop in the axial gauge. Our
arguments use constraints coming only from small gauge Ward identities as well
as the analyticity of the amplitudes, much like the proof in the Abelian case.
Some implications of this result are also discussed.

</DOC>
<DOC>
<DOCNO> 84241 </DOCNO>
Vacuum polarization of scalar fields near Reissner-Nordstr\"{o}m black


  We study vacuum polarization of quantized massive scalar fields $\phi$ in
equilibrium at black-hole temperature in Reissner-Nordstr\"{o}m background. By
means of the Euclidean space Green's function we analytically derive the
renormalized expression $<\phi^{2}>_{H}$ at the event horizon with the area
$4\pi r_{+}^{2}$. It is confirmed that the polarization amplitude
$<\phi^{2}>_{H}$ is free from any divergence due to the infinite red-shift
effect. Our main purpose is to clarify the dependence of $<\phi^{2}>_{H}$ on
field mass $m$ in relation to the excitation mechanism. It is shown for
small-mass fields with $mr_{+}\ll1$ how the excitation of $<\phi^{2}>_{H}$
caused by finite black-hole temperature is suppressed as $m$ increases, and it
is verified for very massive fields with $mr_{+}\gg1$ that $<\phi^{2}>_{H}$
decreases in proportion to $m^{-2}$ with the amplitude equal to the
DeWitt-Schwinger approximation. In particular, we find a resonance behavior
with a peak amplitude at $mr_{+}\simeq 0.38$ in the field-mass dependence of
vacuum polarization around nearly extreme (low-temperature) black holes. The
difference between Scwarzschild and nearly extreme black holes is discussed in
terms of the mass spectrum of quantum fields dominant near the event horizon.

</DOC>
<DOC>
<DOCNO> 102824 </DOCNO>
Twisted connected sums and special Riemannian holonomy


  We give a new, connected-sum-like construction of Riemannian metrics with
special holonomy $G_2$ on compact 7-manifolds. The construction is based on a
gluing theorem for appropriate elliptic partial differential equations. As a
prerequisite, we also obtain asymptotically cylindrical Riemannian manifolds
with holonomy SU(3) building up on the work of Tian and Yau. Examples of new
topological types of compact 7-manifolds with holonomy $G_2$ are constructed
using Fano 3-folds.

</DOC>
<DOC>
<DOCNO> 10329 </DOCNO>
Phase structure of the QCD vacuum in a magnetic field at low temperature


  We study the QCD phase structure in magnetic field $H$ at low temperature
$T$. The hadronic phase free energy in a constant homogeneous magnetic field is
calculated in one-loop approximation of the chiral perturbation theory. The
dependence of the quark and gluon condensates upon the temperature and field
strength is found. It is shown that the chiral phase transition order parameter
$<\bar q q>$ remains constant provided field strength and temperature are
related via $H=const \cdot T^2$.

</DOC>
<DOC>
<DOCNO> 122840 </DOCNO>
Models for infrared and submillimetre counts and backgrounds


  A simple and versatile parameterized approach to the star formation history
allows a quantitative investigation of the constraints from far infrared and
submillimetre counts and background intensity measurements.
  The models include four spectral components: infrared cirrus, an M82-like
starburst, an Arp220-like starburst and an AGN dust torus. The 60 $\mu$m
luminosity function is determined for each chosen rate of evolution using the
PSCz redshift data for 15000 galaxies. The proportions of each spectral type as
a function of 60 $\mu$m luminosity are chosen for consistency with IRAS and
SCUBA colour-luminosity relations, and with the fraction of AGN as a function
of luminosity found in 12 $\mu$m samples.
  A good fit to the observed counts at 0.44, 2.2, 15, 60, 90, 175 and 850
$\mu$m can be found with pure luminosity evolution in all 3 cosmological models
investigated: $\Omega_o$ = 1, $\Omega_o$ = 0.3 ($\Lambda$ = 0), and $\Omega_o$
= 0.3, $\Lambda$ = 0.7. All 3 models also give an acceptable fit to the
integrated background spectrum. The total mass-density of stars generated is
consistent with that observed, in all 3 cosmological models.

</DOC>
<DOC>
<DOCNO> 69424 </DOCNO>
Verifiable Model of Neutrino Masses from Large Extra Dimensions


  We propose a new scenario of neutrino masses with a Higgs triplet
$(\xi^{++},\xi^+,\xi^0)$ in a theory of large extra dimensions. Lepton number
violation in a distant brane acts as the source of a very small trilinear
coupling of $\xi$ to the standard Higgs doublet in our brane. Small realistic
Majorana neutrino masses are \underline{naturally} obtained with the
fundamental scale $M_* \sim {\cal O}(1)$ TeV, foretelling the possible
discovery of $\xi$ $(m_\xi\lsim M_*)$ at future colliders. Decays of $\xi^{++}$
into same-sign dileptons are fixed by the neutrino mass matrix. Observation of
$\mu-e$ conversion in nuclei is predicted.

</DOC>
<DOC>
<DOCNO> 7891 </DOCNO>
The Partition Function of a Spinor Gas


  For a spinor gas, i.e., a mixture of identical particles with several
internal degrees of freedom, we derive the partition function in terms of the
Feynman-Kac functionals of polarized components. As an example we study a
spin-1 Bose gas with the spins subjected to an external magnetic field and
confined by a parabolic potential. From the analysis of the free energy for a
finite number of particles, we find that the specific heat of this ideal spinor
gas as a function of temperature has two maxima: one is related to a Schottky
anomaly, due to the lifting of the spin degeneracy by the external field, the
other maximum is the signature of Bose-Einstein condensation.

</DOC>
<DOC>
<DOCNO> 116238 </DOCNO>
Forecast and event control: On what is and what cannot be possible


  Consequences of the basic and most evident consistency requirement-that
measured events cannot happen and not happen at the same time-are shortly
reviewed. Particular emphasis is given to event forecast and event control. As
a consequence, particular, very general bounds on the forecast and control of
events within the known laws of physics are derived. These bounds are of a
global, statistical nature and need not affect singular events or groups of
events.

</DOC>
<DOC>
<DOCNO> 119165 </DOCNO>
A Galactic Bar to Beyond the Solar Circle and its Relevance for


  The Galactic kinematics of Mira variables have been studied using infrared
photometry, radial velocities, and Hipparcos parallaxes and proper motions. For
Miras in the period range 145 to 200 days (probably corresponding to [Fe/H] in
the range -0.8 to -1.3) the major axes of the stellar orbits are concentrated
in the first quadrant of Galactic longitude. This is interpreted as a
continuation of the bar-like structure of the Galactic Bulge out to the solar
circle and beyond.

</DOC>
<DOC>
<DOCNO> 68795 </DOCNO>
Naked Singularity and Gauss-Bonnet Term in Brane World Scenarios


  We add a Gauss-Bonnet term to the Einstein-Hilbert action and study the
recent proposal to solve the cosmological constant problem. We also consider
the possibility of adding a dilaton potential to the action. In the absence of
supersymmetry, we obtain first order Bogomol'nyi equation as a
solution-generating method in our scenario. When the coefficient of the
Gauss-Bonnet term is positive, the dilaton potential is bounded below. Assuming
a simple double-well potential, the dilaton field is found to be a kink in the
fifth dimension.

</DOC>
<DOC>
<DOCNO> 120232 </DOCNO>
Galaxies in the infrared


  The mid infrared spectra of the starbursts show the 9.7$\mu m$ silicate
absorption feature and strong mid infrared emission bands centered at 6.2, 7.7,
and 11.3 $\mu$m. Illustrative models of the {\it active} galaxies are
presented: As the starbursts are most likely confined to the central region of
the galaxy the radiative transfer in the nucleus is solved under the assumption
of spherical symmetry. The distribution of stars and dust are adjusted until
the complete infrared spectrum of the galaxies are modeled. The dust is
described as a mixture of large grains, very small grains and PAH, which are
undergoing temperature fluctuations. Although the galactic nuclei are deeply
hidden in the dust its global structure can be estimated by the simple
calculations presented. ISOPHOT samples of eleven {\it active} galaxies and
seven {\it inactive} spirals are presented. The far infrared and submillimeter
spectrum of the {\it active} galaxies can be described by a single modified
black--body at a color temperature of $31.5 \pm 2.8$ K. This leads to a ratio
of infrared luminosity to gas mass, $L_{\rm IR}/M_{\rm gas}$, of $\sim 90$
L$_\odot$/ M$_\odot$. In contrast, the spectral energy distributions of {\it
inactive} spirals require, apart from warm dust of $31.8 \pm 2.8$ K, an
additional very cold component of at most $12.9\pm 1.7$ K. This implies a
$L_{\rm IR}/M_{\rm gas}$ ratio of $\sim 3$ L$_\odot$/ M$_\odot$ for the {\it
inactive} spirals, a factor $\sim 30$ lower than for the {\it active} galaxies.
The detection of such cold dust can be predicted by radiative transfer models.

</DOC>
<DOC>
<DOCNO> 100965 </DOCNO>
The standard deviation effect (or why one should sit first base playing


  For a balanced cardcounting system we study the random variable of the true
count after a number of cards are removed from the remaining deck and we prove
a close formula for its standard deviation. As expected, the formula shows that
the standard deviation increases with the number of cards removed. This creates
a "standard deviation effect" with a two fold consequence: longer long run and
presumably larger fluctuations of the bankroll, but a small gain in playing
accuracy for the player sitting third base. The opposite happens for the player
sitting first base. Thus the optimal position in casino blackjack in terms of
shorter long run is first base.

</DOC>
<DOC>
<DOCNO> 178933 </DOCNO>
The production of charm mesons from quark matter at CERN SPS and RHIC


  We study the production of charm mesons and other charm baryons from quark
matter at CERN SPS and RHIC energies. Using quark coalescence models as
hadronization mechanism, we predict particle ratios, absolute yields and
transverse momentum spectra.

</DOC>
<DOC>
<DOCNO> 70153 </DOCNO>
Parallelizing the Symbolic Manipulation Program FORM Part I: Workstation


  The present paper is the first of a series of papers reporting on the
parallelization of the symbolic manipulation program FORM on different parallel
architectures. Part I deals with workstation clusters using dedicated network
hardware and the messages passing libraries (MPI and PVM). After a short
introduction to the sequential version of FORM a detailed analysis of the
different platforms used is given and the structure of the parallel version of
FORM is explained. The forthcoming part II will describe the parallelization of
FORM on SMP (symmetrical multi-processing) architectures.

</DOC>
<DOC>
<DOCNO> 68673 </DOCNO>
Bounds on extra quark-lepton generations from precision measurements


  The existence of extra chiral generations is strongly disfavored by the
precision electroweak data if all the extra fermions are heavier than m_Z.
However fits as good as the SM can be obtained if one allows the new neutral
leptons to have masses close to 50 GeV. In the framework of SUSY models
precision measurements cannot exclude one additional generation of heavy
fermions if chargino and neutralino have masses around 60 GeV with delta_m
around 1 GeV.

</DOC>
<DOC>
<DOCNO> 13581 </DOCNO>
Peak effect in laser ablated DyBa2Cu3O7-d films at microwave frequencies


  In this paper we report the observation of a peak in the microwave surface
resistance (at frequencies ~10GHz) of laser ablated DyBa2Cu3O7-d films in
magnetic field ranging from 2 to 9kOe (||c) close to the superconducting
transition temperature (Tc(H)). The exact nature of peak is sample dependent
but it follows a general behaviour. The peak shifts to lower temperature when
the magnetic field is increased. It has strong frequency dependence and the
peak is pronounced at frequencies close to the depinning frequency of the flux
line lattice. From the observed temperature and field dependence we argue that
this peak is associated with the order disorder transition of the flux line
lattice close to Tc(H).

</DOC>
<DOC>
<DOCNO> 68240 </DOCNO>
On Perturbative Gravity and Gauge Theory


  We review some applications of tree-level (classical) relations between
gravity and gauge theory that follow from string theory. Together with
$D$-dimensional unitarity, these relations can be used to perturbatively
quantize gravity theories, i.e. they contain the necessary information for
obtaining loop contributions. We also review recent applications of these ideas
showing that N=1 D=11 supergravity diverges, and review arguments that N=8 D=4
supergravity is less divergent than previously thought, though it does appear
to diverge at five loops. Finally, we describe field variables for the
Einstein-Hilbert Lagrangian that help clarify the perturbative relationship
between gravity and gauge theory.

</DOC>
<DOC>
<DOCNO> 178650 </DOCNO>
On the Migdal-Watson approach to FSI effects in meson production in NN


  The influence of the nucleon-nucleon final state interaction (FSI) on
properties of the meson production amplitude near threshold is discussed. For
the nucleon-nucleon interaction a simple Yamaguchi potential as well as
realistic potential models are considered. It is shown that FSI effects cannot
be factorized from the production amplitude. The absolute magnitude of FSI
effects depends on the momentum transfer (or on the mass of the produced meson)
and hence is not universal. Only in the case of the production of rather heavy
mesons like eta' or phi FSI effects become universal. The Jost function
approach to FSI effects is critically examined.

</DOC>
<DOC>
<DOCNO> 39697 </DOCNO>
Study of Two-Body B Decays to Kaons and Pions: Observation of B->pi+pi-,


  We have studied charmless hadronic decays of B mesons into two-body final
states with kaons and pions and observe three new processes with the following
branching fractions: BR(B-> pi+ pi-) = (4.3^{+1.6}_{-1.4} \pm 0.5) \times
10^{-6}, BR(B-> K0 pi0) = (14.6^{+5.9+2.4}_{-5.1-3.3}) \times 10^{-6}, and
BR(B-> K+- pi0) = (11.6^{+3.0+1.4}_{-2.7-1.3}) \times 10^{-6}. We also update
our previous measurements for the decays B->K+- pi-+ and B-> K0 pi+-.

</DOC>
<DOC>
<DOCNO> 40131 </DOCNO>
Wavelet-patterns in nucleus-nucleus collisions at 158A GeV


  We propose to use {\it multidimensional} \w \an for pattern recognition in
high multiplicity events and consider some examples. Wavelet analysis reveals
clustering phenomena in multiparticle production processes. Results of
event-by-event studies of some nucleus-nucleus collisions at 158A GeV are
reported. The clusterization topology is found to be different in different
events. Typical patterns include jets and ring-like structures. They are
demonstrated here for five high multiplicity events.

</DOC>
<DOC>
<DOCNO> 118602 </DOCNO>
Searching for periodicities in the MACHO light curve of LMC X-2


  Using the exceptional long-term monitoring capabilities of the MACHO project,
we present here the optical history of LMC X-2 for a continuous 6-yr period.
These data were used to investigate the previously claimed periodicities for
this source of 8.15 h and 12.54 d : we find upper amplitude limits of 0.10 mag
and 0.09 mag, respectively.

</DOC>
<DOC>
<DOCNO> 118308 </DOCNO>
The SCUBA Local Universe Galaxy Survey I: First Measurements of the


  We have used SCUBA to observe a complete sample of 104 galaxies selected at
60 microns from the IRAS BGS and we present here the 850 micron measurements.
Fitting the 60,100 and 850 micron fluxes with a single temperature dust model
gives the sample mean temperature T=36 K and beta = 1.3. We do not rule out the
possibility of dust which is colder than this, if a 20 K component was present
then our dust masses would increase by factor 1.5-3. We present the first
measurements of the luminosity and dust mass functions, which were well fitted
by Schechter functions (unlike those 60 microns). We have correlated many
global galaxy properties with the submillimetre and find that there is a
tendancy for less optically luminous galaxies to contain warmer dust and have
greater star formation efficiencies (cf. Young 1999). The average gas-to-dust
ratio for the sample is 581 +/- 43 (using both atomic and molecular hydrogen),
significantly higher than the Galactic value of 160. We believe this
discrepancy is due to a cold dust component at T < 20 K. There is a suprisingly
tight correlation between dust mass and the mass of molecular hydrogen as
estimated from CO measurements, with an intrinsic scatter of ~50%.

</DOC>
<DOC>
<DOCNO> 13799 </DOCNO>
Staggered magnetization, critical behavior and weak ferromagnetic


  We present a study of a microtwinned single crystal of LaMnO$_3$ by means of
implanted muons. Two muon stopping sites are identified from the symmetry of
the internal field in the ordered phase. The temperature dependence of these
fields yields the behavior of the staggered magnetization from which a static
critical exponent ($\beta=0.36(2)$) is extracted and discussed. The muon
spin-spin relaxation rate shows a critical slowing down (contrary to
preliminary findings) with a critical exponent $n=0.7(1)$, witnessing the Ising
nature of the dynamic fluctuations. The muon precession frequencies vs. applied
magnetic field reveal the saturation of the weak ferromagnetic domain structure
originated by the Dzialoshinski-Moriya antisymmetric exchange.

</DOC>
<DOC>
<DOCNO> 85281 </DOCNO>
Riemann normal coordinates, Fermi reference system and the geodesic


  We obtain the integral formulae for computing the tetrads and metric
components in Riemann normal coordinates and Fermi coordinate system of an
observer in arbitrary motion. Our approach admits essential enlarging the range
of validity of these coordinates. The results obtained are applied to the
geodesic deviation in the field of a weak plane gravitational wave and the
computation of plane-wave metric in Fermi normal coordinates.

</DOC>
<DOC>
<DOCNO> 117362 </DOCNO>
The BeppoSAX High Energy Large Area Survey (HELLAS): a progress Report


  The integrated emission of highly obscured AGN is expected to provide a major
contribution to the X-ray energy density in the Universe: the X-ray background
(XRB). The study of these objects is possible only at energies where the
effects of absorption are less severe. For this reason we have carried out the
BeppoSAX High Energy LLarge Area Survey in the hardest band (5-10 keV)
accessible so far with imaging X-ray instruments. The source surface density at
the survey limiting flux accounts for a significant fraction (20-30%) of the
hard XRB. The X-ray data complemented by multiwavelength follow--up
observations suggest that a large fraction of the hard sources are AGN and that
X-ray absorption with column densities in the range 10^22-23.5 cm-2 is common
among them. The great diversity in their optical-near-IR properties suggests
that the optical appearance of obscured sources is a function of the X-ray
luminosity. We briefly discuss the implications of these findings for the XRB
models.

</DOC>
<DOC>
<DOCNO> 99652 </DOCNO>
Statistical mechanics approach to some problems in conformal geometry


  A weak law of large numbers is established for a sequence of systems of N
classical point particles with logarithmic pair potential in $\bbR^n$, or
$\bbS^n$, $n\in \bbN$, which are distributed according to the configurational
microcanonical measure $\delta(E-H)$, or rather some regularization thereof,
where H is the configurational Hamiltonian and E the configurational energy.
When $N\to\infty$ with non-extensive energy scaling $E=N^2 \vareps$, the
particle positions become i.i.d. according to a self-consistent Boltzmann
distribution, respectively a superposition of such distributions. The
self-consistency condition in n dimensions is some nonlinear elliptic PDE of
order n (pseudo-PDE if n is odd) with an exponential nonlinearity. When n=2,
this PDE is known in statistical mechanics as Poisson-Boltzmann equation, with
applications to point vortices, 2D Coulomb and magnetized plasmas and
gravitational systems. It is then also known in conformal differential
geometry, where it is the central equation in Nirenberg's problem of prescribed
Gaussian curvature. For constant Gauss curvature it becomes Liouville's
equation, which also appears in two-dimensional so-called quantum Liouville
gravity. The PDE for n=4 is Paneitz' equation, and while it is not known in
statistical mechanics, it originated from a study of the conformal invariance
of Maxwell's electromagnetism and has made its appearance in some recent model
of four-dimensional quantum gravity. In differential geometry, the Paneitz
equation and its higher order n generalizations have applications in the
conformal geometry of n-manifolds, but no physical applications yet for general
n. Interestingly, though, all the Paneitz equations have an interpretation in
terms of statistical mechanics.

</DOC>
<DOC>
<DOCNO> 40320 </DOCNO>
Measurement of B0 and B+ lifetimes and B0-antiB0 mixing with fully


  Time-dependent B0-antiB0 flavor oscillations and B0 and B+ lifetimes are
studied in a sample of fully reconstructed B mesons collected with the BaBar
detector, running at the PEP-II asymmetric e+e- B Factory with center-of-mass
energies near the Upsilon(4S) resonance. This is the first time that
time-dependent mixing and lifetime measurements have been performed at
Upsilon(4S) energies.

</DOC>
<DOC>
<DOCNO> 8500 </DOCNO>
Some remarks on the Lieb-Schultz-Mattis theorem and its extension to


  The extension of the Lieb-Schultz-Mattis theorem to dimensions larger than
one is discussed. It is explained why the variational wave-function built by
the previous authors is of no help to prove the theorem in dimension larger
than one. The short range R.V.B. picture of Sutherland, Rokhsar and Kivelson,
Read and Chakraborty gives a strong support to the assertion that the theorem
is indeed valid in any dimension. Some illustrations of the general ideas are
displayed on exact spectra.

</DOC>
<DOC>
<DOCNO> 169904 </DOCNO>
Quantum computing with trapped ions, atoms and light


  We first consider the basic requirements for a quantum computer, arguing for
the attractiveness of nuclear spins as information-bearing entities, and light
for the coupling which allows quantum gates. We then survey the strengths of
and immediate prospects for quantum information processing in ion traps. We
discuss decoherence and gate rates in ion traps, comparing methods based on the
vibrational motion with a method based on exchange of photons in cavity QED. We
then sketch the main features of a quantum computer designed to allow an
algorithm needing 10^6 Toffoli gates on 100 logical qubits. We find that around
200 ion traps linked by optical fibres and high-finesse cavities could perform
such an algorithm in a week to a month, using components at or near current
levels of technology.

</DOC>
<DOC>
<DOCNO> 152640 </DOCNO>
A D2-brane realization of Maxwell-Chern-Simons-Higgs systems


  We show that N=2 supersymmetric Maxwell-Chern-Simons-Higgs systems in three
dimension can be realized as gauge theories on a D2-brane in D8-branes
background with a non-zero B-field. We reproduce a potential of Coulomb branch
of the Chern-Simons theory as a potential of a D2-brane in a classical D8-brane
solution and show that each Coulomb vacuum is realized by a D2-brane stabilized
in the bulk at a certain distance from D8-branes.

</DOC>
<DOC>
<DOCNO> 84496 </DOCNO>
Covariant symplectic structure of the complex Monge-Amp\`ere equation


  The complex Monge-Amp\`ere equation admits covariant bi-symplectic structure
for complex dimension 3, or higher. The first symplectic 2-form is obtained
from a new variational formulation of complex Monge- Amp\`ere equation in the
framework of the covariant Witten-Zuckerman approach to symplectic structure.
We base our considerations on a reformulation of the Witten-Zuckerman theory in
terms of holomorphic differential forms. The first closed and conserved
Witten-Zuckerman symplectic 2-form for the complex Monge-Amp\`ere equation is
obtained in arbitrary dimension and for all cases elliptic, hyperbolic and
homogeneous.
   The connection of the complex Monge-Amp\`ere equation with Ricci-flat
K\"ahler geometry suggests the use of the Hilbert action. However, we point out
that Hilbert's Lagrangian is a divergence for K\"ahler metrics. Nevertheless,
using the surface terms in the Hilbert Lagrangian we obtain the second
Witten-Zuckerman symplectic 2-form for complex dimension>2.

</DOC>
<DOC>
<DOCNO> 10369 </DOCNO>
Equilibrium shapes and faceting for ionic crystals of


  A mean field theory is developed for the calculation of the surface free
energy of the staggered BCSOS, (or six vertex) model as function of the surface
orientation and of temperature. The model approximately describes surfaces of
crystals with nearest neighbor attractions and next nearest neighbor
repulsions. The mean field free energy is calculated by expressing the model in
terms of interacting directed walks on a lattice. The resulting equilibrium
shape is very rich with facet boundaries and boundaries between reconstructed
and unreconstructed regions which can be either sharp (first order) or smooth
(continuous). In addition there are tricritical points where a smooth boundary
changes into a sharp one and triple points where three sharp boundaries meet.
Finally our numerical results strongly suggest the existence of conical points,
at which tangent planes of a finite range of orientations all intersect each
other. The thermal evolution of the equilibrium shape in this model shows
strong similarity to that seen experimentally for ionic crystals.

</DOC>
<DOC>
<DOCNO> 84506 </DOCNO>
Large-scale CMB anisotropies: wrinkles in the Galaxy rather than in time


  Withdrawm.
  Public data of COBE-DMR are not perfectly subtracted from dipole. Therefore,
the Galactic latitude dependence is affected by the remnants of the dipole and
the results previously announced in this paper about this are not valid.
  Anyway, the suspect of a high Galactic contamination announced in another
paper (Lopez-Corredoira 1999; A&A 346, 369) is still valid and to be
considered.
  Thanks are given to Ted Bunn for helpful discussions which made me realize of
the problem with the dipole.

</DOC>
<DOC>
<DOCNO> 116646 </DOCNO>
A Novel Approach to Structure Alignment


  A novel approach for structure alignment is presented, where the key
ingredients are: (1) An error function formulation of the problem
simultaneously in terms of binary (Potts) assignment variables and real-valued
atomic coordinates. (2) Minimization of the error function by an iterative
method, where in each iteration a mean field method is employed for the
assignment variables and exact rotation/translation of atomic coordinates is
performed, weighted with the corresponding assignment variables. The approach
allows for extensive search of all possible alignments, including those
involving arbitrary permutations. The algorithm is implemented using a C_alpha
representation of the backbone and explored on different protein structure
categories using the Protein Data Bank (PDB) and is successfully compared with
other algorithms. The approach performs very well with modest CPU consumption
and is robust with respect to choice of parameters. It is extremely generic and
flexible and can handle additional user-prescribed constraints easily.
Furthermore, it allows for a probabilistic interpretation of the results.

</DOC>
<DOC>
<DOCNO> 13052 </DOCNO>
Effects of Disorder on Ferromagnetism in Diluted Magnetic Semiconductors


  We present results of a numerical mean field treatment of interacting spins
and carriers in doped diluted magnetic semiconductors, which takes into account
the positional disorder present in these alloy systems. Disorder is found to
enhance the ferromagnetic transition temperature significantly for metallic
densities not too far from the metal-insulator transition. Concurrently, the
ferromagnetic phase is found to have very unusual temperature dependence of the
magnetization as well as specific heat as a result of disorder. Unusual spin
and charge transport is implied.

</DOC>
<DOC>
<DOCNO> 99360 </DOCNO>
Perturbed Poeschl-Teller oscillators


  Wave functions and energies are constructed in a short-range Poeschl-Teller
well (= negative quadratic secans hyperbolicus) with a quartic perturbation.
Within the framework of an innovated, Lanczos-inspired perturbation theory we
show that our choice of non-orthogonal basis makes all the corrections given by
closed formulae. The first few items are then generated using MAPLE.

</DOC>
<DOC>
<DOCNO> 84467 </DOCNO>
Brane-worlds and their Deformations


  A geometric theory of brane-worlds with large or non-compact extra dimensions
is presented. It is shown that coordinate gauge independent perturbations of
the brane-world correspond to the Einstein-Hilbert dynamics derived from the
embeddings of the brane-world. The quantum states of a perturbation are
described by Schr\"odinger's equation with respect to the extra dimensions and
the deformation Hamiltonian. A gauge potential with confined components is
derived from the differentiable structure of the brane-world

</DOC>
<DOC>
<DOCNO> 102185 </DOCNO>
The Kauffman bracket skein as an algebra of observables


  We prove that the Kauffman bracket skein algebra of a cylinder over a surface
with boundary, defined over complex numbers, is isomorphic to the observables
of an appropriate lattice gauge field theory.

</DOC>
<DOC>
<DOCNO> 100126 </DOCNO>
The Connes-Higson construction is an isomorphism


  Let $A$ be a separable $C^*$-algebra and $B$ a stable $C^*$-algebra
containing a strictly positive element. We show that the group $\Ext(SA,B)$ of
unitary equivalence classes of extensions of $SA$ by $B$, modulo the extensions
which are asymptotically split, coincides with the group of homotopy classes of
such extensions. This is done by proving that the Connes-Higson construction
gives rise to an isomorphism between $\Ext(SA,B)$ and the $E$-theory group
$E(A,B)$ of homotopy classes of asymptotic homomorphisms from $S^2A$ to $B$.

</DOC>
<DOC>
<DOCNO> 85561 </DOCNO>
Note on Signature Change and Colombeau Theory


  Recent work alludes to various `controversies' associated with signature
change in general relativity. As we have argued previously, these are in fact
disagreements about the (often unstated) assumptions underlying various
possible approaches. The choice between approaches remains open.

</DOC>
<DOC>
<DOCNO> 72268 </DOCNO>
A Few Aspects of Heavy Quark Expansion


  Two topics in heavy quark expansion are discussed. The heavy quark potential
in perturbation theory is reviewed in connection to the problem of the heavy
quark mass. The nontrivial reason behind the failure of the "potential
subtracted" mass in higher orders is elucidated. The heavy quark sum rules are
the second subject. The physics behind the new exact sum rules is described and
a simple quantum mechanical derivation is given. The question of saturation of
sum rules is discussed. A comment on the nonstandard possibility which would
affect analysis of BR_sl(B) vs. n_c is made.

</DOC>
<DOC>
<DOCNO> 118247 </DOCNO>
Measuring the Nonlinear Biasing Function from a Galaxy Redshift Survey


  We present a simple method for evaluating the nonlinear biasing function of
galaxies from a redshift survey. The nonlinear biasing is characterized by the
conditional mean of the galaxy density fluctuation given the underlying mass
density fluctuation, or by the associated parameters of mean biasing and
nonlinearity (following Dekel & Lahav 1999). Using the distribution of galaxies
in cosmological simulations, at smoothing of a few Mpc, we find that the mean
biasing can be recovered to a good accuracy from the cumulative distribution
functions (CDFs) of galaxies and mass, despite the biasing scatter. Then, using
a suite of simulations of different cosmological models, we demonstrate that
the matter CDF is robust compared to the difference between it and the galaxy
CDF, and can be approximated for our purpose by a cumulative log-normal
distribution of 1+\delta with a single parameter \sigma. Finally, we show how
the nonlinear biasing function can be obtained with adequate accuracy directly
from the observed galaxy CDF in redshift space. Thus, the biasing function can
be obtained from counts in cells once the rms mass fluctuation at the
appropriate scale is assumed a priori. The relative biasing function between
different galaxy types is measurable in a similar way. The main source of error
is sparse sampling, which requires that the mean galaxy separation be smaller
than the smoothing scale. Once applied to redshift surveys such as PSCz, 2dF,
SDSS, or DEEP, the biasing function can provide valuable constraints on galaxy
formation and structure evolution.

</DOC>
<DOC>
<DOCNO> 121995 </DOCNO>
The autocorrelation function of the soft X-ray background


  The first positive detection of the X-ray background fluctuations at small
angular scales is reported. ROSAT PSPC archive pointed observations are used to
measure fluctuations at scales of 0.03 - 0.4 deg. The pointings have been
selected from an area free from galactic contamination. At separations below
0.1 deg clusters of galaxies become a substantial source of the background
fluctuations. The autocorrelation function of the fluctuations in the power law
approximation has a slope of ~1 for all the data but is substantially flatter
(with slope of ~0.7) when pointings containing bright clusters are removed. At
separations 0.3 - 0.4 deg where the ACF estimates based on the ROSAT pointings
and All-Sky Survey are available, both data sets give consistent results.

</DOC>
<DOC>
<DOCNO> 10451 </DOCNO>
Resistivity and 1/f Noise in Non-Metallic Phase Separated Manganites


  A simple model is proposed to calculate resistivity, magnetoresistance, and
noise spectrum in non-metallic phase-separated manganites containing small
metallic droplets (magnetic polarons). The system is taken to be far from the
percolation transition into a metallic state. It is assumed that the charge
transfer occurs due to electron tunneling from one droplet to another through
the insulating medium. As a result of this tunneling, the droplets acquire or
lose extra electrons forming metastable two-electron and empty states. In the
framework of this model, explicit expressions for dc conductivity and noise
power of the system are derived. It is shown that the noise spectrum has 1/f
form in the low-frequency range.

</DOC>
<DOC>
<DOCNO> 151520 </DOCNO>
Consistent Warped-Space Kaluza-Klein Reductions, Half-Maximal Gauged


  We obtain new consistent Kaluza-Klein embeddings of the gauged supergravities
with half of maximal supersymmetry in dimensions D=7, 6, 5 and 4. They take the
form of warped embeddings in type IIA, type IIB, M-theory and type IIB
respectively, and are obtained by performing Kaluza-Klein circle reductions or
T-duality transformations on Hopf fibres in S^3 submanifolds of the
previously-known sphere reductions. The new internal spaces are in some sense
``mirror manifolds'' that are dual to the original internal spheres. The vacuum
AdS solutions of the gauged supergravities then give rise to warped products
with these internal spaces. As well as these embeddings, which have
singularities, we also construct new non-singular warped Kaluza-Klein
embeddings for the D=5 and D=4 gauged supergravities. The geometry of the
internal spaces in these cases leads us to study Fubini-Study metrics on
complex projective spaces in some detail.

</DOC>
<DOC>
<DOCNO> 8965 </DOCNO>
Defect-unbinding and the Bose-glass transition in layered


  The low-field Bose-glass transition temperature in heavy-ion irradiated
Bi_2Sr_2CaCu_2O_8+d increases progressively with increasing density of
irradiation-induced columnar defects, but saturates for densities in excess of
1.5 x10^9 cm^-2. The maximum Bose-glass temperature corresponds to that above
which diffusion of two-dimensional pancake vortices between different vortex
lines becomes possible, and above which the ``line-like'' character of vortices
is lost. We develop a description of the Bose-glass line that is in excellent
quantitative agreement with the experimental line obtained for widely different
values of track density and material parameters.

</DOC>
<DOC>
<DOCNO> 10752 </DOCNO>
Comment on the paper: Quantum backaction of optical observations on


  A recent paper, Quantum backaction of optical observations on Bose-Einstein
condensates by U. Leonhardt, T. Kiss, and P. Piwnicki, Eur. Phys. J. D7, 413
(1999), emphasized that the limit of dispersive imaging of Bose-Einstein
condensates with off-resonant light is not residual absorption, but a different
form of quantum backaction of the probe light. This note points out that these
conclusions are incorrect, and that Rayleigh scattering is the dominant quantum
backaction of dispersive imaging.

</DOC>
<DOC>
<DOCNO> 40013 </DOCNO>
QCD and the Structure of the Nucleon in Electron Scattering


  The internal structure of the nucleon is discussed within the context of QCD.
Recent progress in understanding the distribution of flavor and spin in the
nucleon is reviewed, and prospects for extending our knowledge of nucleon
structure in electron scattering experiments at modern facilities such as
Jefferson Lab are outlined.

</DOC>
<DOC>
<DOCNO> 100454 </DOCNO>
Rapidly converging series for the Weierstrass zeta-function and the


  We present expressions for the Weierstrass zeta-function and related elliptic
functions by rapidly converging series. These series arise as triple products
in the A-infinity category of an elliptic curve.

</DOC>
<DOC>
<DOCNO> 121041 </DOCNO>
A Shock-Induced PDR in the HH 80/81 Flow. Far Infrared Spectroscopy


  The two spectrometers on board the Infrared Space Observatory were used to
observe the Herbig-Haro objects HH 80, 81 and 80N, as well as their candidate
exciting source IRAS 18162-2048. The fine structure lines of [OI]63um,
[OI]145um and [CII]158um are detected everywhere, while [NII]122um and
[OIII]88um are only detected toward the HH objects; line ratios confirm for the
first time the collisionally excited HH nature of HH 80N. No molecular line is
detected in any of the observed positions. We use a full shock code to diagnose
shock velocities vs~100 km/s toward the HH objects, as expected from the
optical spectroscopy. Since proper motions suggest velocities in excess of 600
km/s, the HH objects probably represent the interface between two flow
components with velocity differing by ~vs. Aside from the flow exciting source,
the [CII]158um line is everywhere brighter than the [OI]63um line, indicating
the presence of a Photo-Dissociation Region (PDR) all along the flow. Continuum
emission from the HH objects and from other positions along the flow is only
detected longword of ~50 micron, and its proportionality to the [CII]158um line
flux suggests it is PDR in origin. We propose that the FUV continuum irradiated
by the HH objects and the jet is responsible for the generation of a PDR at the
walls of the flow cavity. We develop a very simple model which strengthens the
plausibility of this hypothesis.

</DOC>
<DOC>
<DOCNO> 72217 </DOCNO>
Split Fermions in Extra Dimensions and CP Violation


  We discuss CP violation in the quark sector within a novel approach to the
Yukawa puzzle proposed by Arkani-Hamed and Schmaltz, where Yukawa hierarchies
result from localising the Standard Model quark field wave-functions, at
different positions (in the extra dimensions) in a ``fat-brane.'' We show that
at least two extra dimensions are necessary in order to obtain sufficient CP
violation while reproducing the correct quark mass spectrum and mixing angles.

</DOC>
<DOC>
<DOCNO> 9929 </DOCNO>
Exact equqations and scaling relations for f-avalanche in the


  Infinite hierarchy of exact equations are derived for the newly-observed
f-avalanche in the Bak-Sneppen evolution model. By solving the first order
exact equation, we found that the critical exponent which governs the
divergence of the average avalanche size, is exactly 1 (for all dimensions),
confirmed by the simulations. Solution of the gap equation yields another
universal exponent, denoting the the relaxation to the attractor, is exactly 1.
We also establish some scaling relations among the critical exponents of the
new avalanche.

</DOC>
<DOC>
<DOCNO> 68991 </DOCNO>
Renormalization of the Cabibbo-Kobayashi-Maskawa Matrix


  Using the on-shell scheme and the general linear R_xi gauge we have
calculated the one-loop amplitude W+ -> u_I d_j. In agreement with previous
work we have shown that the Cabibbo-Kobayashi-Maskawa (CKM) matrix ought to be
renormalized. We show how to renormalize the CKM matrix and, at the same time,
obtain a gauge independent W decay amplitude.

</DOC>
<DOC>
<DOCNO> 121908 </DOCNO>
The Nuclear Stellar Cluster in the Seyfert~1 Galaxy NGC 3227: High


  NIR high angular resolution speckle imaging and imaging spectroscopy of the
nuclear region (10'' ~ 840pc) of the Seyfert1 galaxy NGC3227 are presented. A
nuclear stellar cluster is slightly resolved in the J and H band with
increasing contribution to the NIR continuum from the K to the J band. The
stellar absorption lines are extended compared to the neighboring continuum
suggesting a cluster size of ~ 70pc FWHM. Analysis of those lines suggests that
the stars are contributing about 65% (40%) of the total continuum emission in
the H (K) band in a 3.6'' aperture. Population synthesis in conjunction with
NIR spectral synthesis indicates an age of 25 to 50 Myr when red supergiants
contribute most to the NIR light. This is supported by published optical data
on the MgIb line and the CaII triplet. Although a higher age of ~ 0.5 Gyr where
AGB stars dominate the NIR light can not be excluded, the observed parameters
are at the limit of those expected for a cluster dominated by AGB stars.
However, in either case the resolved stellar cluster contributes only about ~
15 % of the total dynamical mass in the inner 300pc implying another much older
stellar population. Pure constant star formation over the last 10 Gyr can be
excluded. Therefore, at least two star formation/starburst events took place in
the nucleus of NGC3227. Since such sequences in the nuclear star formation
history are also observed in the nuclei of other galaxies a link between the
activity of the star formation and the AGN itself seems likely.

</DOC>
<DOC>
<DOCNO> 121451 </DOCNO>
Polarization measurements of Vega-like stars


  Optical linear polarization measurements are presented for about 30 Vega-like
stars. These are then compared with the polarization observed for normal field
stars. A significant fraction of the Vega-like stars are found to show
polarization much in excess of that expected to be due to interstellar matter
along the line of sight to the star. The excess polarization must be intrinsic
to the star, caused by circumstellar scattering material that is distributed in
a flattened disk. A correlation between infrared excess and optical
polarization is found for the Vega-like stars.

</DOC>
<DOC>
<DOCNO> 151249 </DOCNO>
Conformal String Sector of M-Theory


  We consider a conformal system of a string and a particle defined in D=10+2
space-time dimensions. The extra time-like dimension is a gauge artifact and
can be eliminated by choosing a gauge in which the SO(10,1) Lorentz symmetry is
manifest. The effective theory of string observables is the 11d supergravity.
The same theory compactified on T^2 provides a non-perturbative unified picture
of the Type IIA, Type IIB and 11d supergravity. This is confirmed by explicit
determination of the R^4-terms which are finite and manifestly SL(2,Z)
invariant as expected by the U-duality conjecture in nine non-compact
dimensions with maximal supersymmetry.

</DOC>
<DOC>
<DOCNO> 12945 </DOCNO>
Scaling and Crossover to Tricriticality in Polymer Solutions


  We propose a scaling description of phase separation of polymer solutions.
The scaling incorporates three universal limiting regimes: the Ising limit
asymptotically close to the critical point of phase separation, the "ideal-gas"
limit for the pure-solvent phase, and the tricritical limit for the
polymer-rich phase asymptotically close to the theta point. We have also
developed a phenomenological crossover theory based on the
near-tricritical-point Landau expansion renormalized by fluctuations. This
theory validates the proposed scaled representation of experimental data and
crossover to tricriticality.

</DOC>
<DOC>
<DOCNO> 101310 </DOCNO>
The Weil-Petersson Isometry Group


  We prove that every Weil-Petersson isometry of the Teichmuller space T(g,n)
is induced by an element of the extended mapping class group; here 3g-3+n > 1
and (g,n) is not (1,2). Our method follows Ivanov's proof of the Royden's
analogous theorem for the Teichmuller metric: we study the action of an
isometry on the frontier of the metric completion of the Teichmuller space, and
show that the isometry then induces an automorphism on the relevant complex of
curves. Some synthetic geometry of the Weil-Petersson metric completes the
proof.

</DOC>
<DOC>
<DOCNO> 85545 </DOCNO>
Supermassive boson stars: prospects for observational detection


  In a recent work (Torres, Capozziello and Lambiase, Physical Review D62,
104012 (2000)), it was shown that a supermassive boson star could provide an
alternative model for the galactic center, usually assumed as a black hole.
Here we comment on some of the possibilities to actually detect this object,
and how can it be distinguished from the standard and other alternative models.

</DOC>
<DOC>
<DOCNO> 122746 </DOCNO>
The variable XMM-Newton spectrum of Markarian 766


  The narrow-line Seyfert 1 galaxy Markarian 766 was observed for 60 ks with
the XMM-Newton observatory. The source shows a complex X-ray spectrum. The 2-10
keV spectrum can be adequately represented by a power law and broad Fe Ka
emission. Between 0.7 and 2 keV the spectrum is harder and exhibits a flux
deficit with respect to the extrapolated medium energy slope. Below 0.7 keV,
however, there is a strong excess of emission. The RGS spectrum shows an
edge-like feature at 0.7 keV; the energy of this feature is inconsistent with
that expected for an OVII edge from a warm absorber. Markarian 766 varies by a
factor of ~ 2 in overall count rate in the EPIC and RGS instruments on a
timescale of a few thousand seconds, while no significant flux changes are
observed in the ultraviolet with the OM. The X-ray variability is spectrally
dependent with the largest amplitude variability occurring in the 0.4-2 keV
band. The spectral variability can be explained by a change in flux and slope
of the medium energy continuum emission, superimposed on a less variable (or
constant) low energy emission component.

</DOC>
<DOC>
<DOCNO> 10789 </DOCNO>
Diffusion and Aggregation in an Agent Based Model of Stock Market


  We describe a new model to simulate the dynamic interactions between market
price and the decisions of two different kind of traders. They possess spatial
mobility allowing to group together to form coalitions. Each coalition follows
a strategy chosen from a proportional voting ``dominated'' by a leader's
decision. The interplay of both kind of agents gives rise to complex price
dynamics that is consistent with the main stylized facts of financial time
series.

</DOC>
<DOC>
<DOCNO> 84788 </DOCNO>
Notes for a brief history of quantum gravity


  I sketch the main lines of development of the research in quantum gravity,
from the first explorations in the early thirties to nowadays.

</DOC>
<DOC>
<DOCNO> 178466 </DOCNO>
Superheavy Nuclei in a Chiral Hadronic Model


  Superheavy nuclei are investigated in a nonlinear chiral SU(3)-model. The
proton number Z=120 and neutron numbers of N=172, 184 and 198 are predicted to
be magic. The charge distributions and alpha-decay chains hint towards a hollow
structure.

</DOC>
<DOC>
<DOCNO> 10880 </DOCNO>
Kondo tunneling through real and artificial molecules


  When a cerocene molecule is chemisorbed on metallic substrate, or when an
asymmetric double dot is hybridized with itinerant electrons, its singlet
ground state crosses its lowly excited triplet state, leading to a competition
between the Zhang-Rice mechanism of singlet-triplet splitting in a confined
cluster and the Kondo effect (which accompanies the tunneling through quantum
dot under a Coulomb blockade restriction). The rich physics of an underscreened
S=1 Kondo impurity in the presence of low-lying triplet/singlet excitations is
exposed. Estimates of the magnetic susceptibility and the electric conductance
are presented.

</DOC>
<DOC>
<DOCNO> 12831 </DOCNO>
Canonical and non-canonical equilibrium distribution


  We address the problem of the dynamical foundation of non-canonical
equilibrium. We consider, as a source of divergence from ordinary statistical
mechanics, the breakdown of the condition of time scale separation between
microscopic and macroscopic dynamics. We show that this breakdown has the
effect of producing a significant deviation from the canonical prescription. We
also show that, while the canonical equilibrium can be reached with no apparent
dependence on dynamics, the specific form of non-canonical equilibrium is, in
fact, determined by dynamics. We consider the special case where the thermal
reservoir driving the system of interest to equilibrium is a generator of
intermittent fluctuations. We assess the form of the non-canonical equilibrium
reached by the system in this case. Using both theoretical and numerical
arguments we demonstrate that Levy statistics are the best description of the
dynamics and that the Levy distribution is the correct basin of attraction. We
also show that the correct path to non-canonical equilibrium by means of
strictly thermodynamic arguments has not yet been found, and that further
research has to be done to establish a connection between dynamics and
thermodynamics.

</DOC>
<DOC>
<DOCNO> 9471 </DOCNO>
Nonuniversal correlations in multiple scattering


  We show that intensity of a wave created by a source embedded inside a
three-dimensional disordered medium exhibits a non-universal space-time
correlation which depends explicitly on the short-distance properties of
disorder, source size, and dynamics of disorder in the immediate neighborhood
of the source. This correlation has an infinite spatial range and is
long-ranged in time. We suggest that a technique of "diffuse microscopy" might
be developed employing spatially-selective sensitivity of the considered
correlation to the disorder properties.

</DOC>
<DOC>
<DOCNO> 102172 </DOCNO>
On the chiral ring of Calabi-Yau hypersurfaces in toric varieties


  We study the B-model chiral ring of Calabi-Yau hypersurfaces in Batyrev's
mirror construction. The main result is an explicit description of a subring of
the chiral ring of semiample regular (transversal to torus orbits) Calabi-Yau
hypersurfaces. This subring includes the marginal operators and contains all
information about the correlation functions used by physicists. Computation of
the chiral ring passes through a description of cohomology of semiample
hypersurfaces. Here, we develop the techniques for calculating of the
cohomology of resolutions.

</DOC>
<DOC>
<DOCNO> 120329 </DOCNO>
On Galaxy-Cluster Sizes and Temperatures


  We show that the distribution of the sizes and temperatures of clusters can
be used to constrain cosmological models. The size-temperature (ST)
distribution predicted in a flat Gaussian cluster-abundance-normalized
Omega_0=0.3 model agrees well with the fairly tight ST relation observed. A
larger power-spectrum amplitude sigma_8 would give rise to a larger scatter
about the ST relation as would a larger value of Omega_0 and/or long
non-Gaussian high-density tails in the probability density function. For
Gaussian initial conditions, the ST distribution suggests a constraint sigma_8
Omega_0^{0.26} \simeq 0.76. The ST relation is expected to get tighter at high
redshifts. In the process, we derive a simple formula for the halo
formation-redshift distribution for non-Gaussian models. We also suggest that
the discrepancy between the naive zero-redshift ST relation and that observed
may be due, at least in part, to the fact that lower-mass clusters form over a
wider range of redshifts. An Appendix derives an equation for the
formation-redshift distribution of halos.

</DOC>
<DOC>
<DOCNO> 151092 </DOCNO>
Classical relativistic systems of charged particles in the front form of


  Classical relativistic system of point particles coupled with an
electromagnetic field is considered in the three-dimensional representation.
The gauge freedom connected with the chronometrical invariance of the
four-dimensional description is reduced by use of the geometrical concept of
the forms of relativistic dynamics. The remainder gauge degrees of freedom of
the electromagnetic potential are analysed within the framework of Dirac's
constrained Hamiltonian mechanics in the front form of dynamics. The results
are implemented to the problems of relativistic statistical mechanics. Based on
the corresponding Liouville equation the classical partition function of the
system is written down in a gauge-invariant manner and an integration over
field variables is performed.

</DOC>
<DOC>
<DOCNO> 152527 </DOCNO>
Renormalization Group Flows In The Deformed AdS/CFT Correspondence


  In the AdS/CFT correspondence motion in the radial direction of the AdS space
is identified with renormalization group flow in the field theory. For the N=4
Yang-Mills theory this motion is trivial. More interesting examples of
renormalization group flow occur when the N=4 theory is deformed. Aspects of
the flows are discussed for the N=4 theory on its moduli space, and deformed to
N=2 in the infra-red within the context of 5d SUGRA. 10d lifts and brane
probing are crucial tools for linking the spacetime backgrounds to the dual
field theory.

</DOC>
<DOC>
<DOCNO> 68476 </DOCNO>
Comment on Erratum: Multiparticle Bose-Einstein Correlations, Phys. Rev.


  The formulas in the above Erratum are corrected.

</DOC>
<DOC>
<DOCNO> 152085 </DOCNO>
Cohomology and Topological Anomalies


  The chiral anomaly can be considered as an object defined either on the space
of gauge potentials or on the orbit space. We will discuss the relation between
the two descriptions. We will also relate to the cohomology of the group of
gauge transformations.

</DOC>
<DOC>
<DOCNO> 121634 </DOCNO>
Intermediate Velocity Clouds - Distances, Infall and Shadowing


  We present the current distance estimates to 11 intermediate velocity clouds
(IVCs) which are part of the David Dunlap Observatory Intermediate Velocity
Cloud (DDO IVC) Distance Project (Clarke et al. 1999). We briefly discuss
constraints these place on infall models and show the potential of IVCs to
constrain the radial distribution of hot gas in the Galaxy through shadowing of
the soft X-ray background.

</DOC>
<DOC>
<DOCNO> 170292 </DOCNO>
On quantum coding for ensembles of mixed states


  We consider the problem of optimal asymptotically faithful compression for
ensembles of mixed quantum states. Although the optimal rate is unknown, we
prove upper and lower bounds and describe a series of illustrative examples of
compression of mixed states. We also discuss a classical analogue of the
problem.

</DOC>
<DOC>
<DOCNO> 13977 </DOCNO>
Vortex Collisions: Crossing or Recombination?


  We investigate the collision of two vortex lines moving with viscous dynamics
and driven towards each other by an applied current. Using London theory in the
approach phase we observe a non-trivial vortex conformation producing
anti-parallel segments; their attractive interaction triggers a violent
collision. The collision region is analyzed using the time-dependent
Ginzburg-Landau equation. While we find vortices will always recombine through
exchange of segments, a crossing channel appears naturally through a double
collision process.

</DOC>
<DOC>
<DOCNO> 169692 </DOCNO>
On the Non-Orthonormality of Lippmann-Schwinger-Low States


  It is pointed out that for a general short-ranged potential the
Lippmann-Schwinger-Low scattering state $|\psi^L_k>$ does not strictly satisfy
the Schrodinger eigen equation, and the pair $|\psi^L_n>$, $|\psi^L_k>$ is
mutually nonorthogonal if $E_n=E_k$. For this purpose, we carefully use an
infinitesimal adiabatic parameter $\epsilon$, a nonlinear relation among
transition amplitudes, and a separable interaction as illustration.

</DOC>
<DOC>
<DOCNO> 121370 </DOCNO>
A Lack of Planets in 47 Tucanae from an HST Search


  We report results from a large Hubble Space Telescope project to observe a
significant (~34,000) ensemble of main sequence stars in the globular cluster
47 Tucanae with a goal of defining the frequency of inner-orbit, gas-giant
planets. Simulations based on the characteristics of the 8.3 days of
time-series data in the F555W and F814W WFPC2 filters show that ~17 planets
should be detected by photometric transit signals if the frequency of hot
Jupiters found in the solar neighborhood is assumed to hold for 47 Tuc. The
experiment provided high-quality data sufficient to detect planets. A full
analysis of these WFPC2 data reveals ~75 variables, but NO light curves
resulted for which a convincing interpretation as a planet could be made. The
planet frequency in 47 Tuc is at least an order of magnitude below that for the
solar neighborhood. The cause of the absence of close-in planets in 47 Tuc is
not yet known; presumably the low metallicity and/or crowding of 47 Tuc
interfered with planet formation, with orbital evolution to close-in positions,
or with planet survival.

</DOC>
<DOC>
<DOCNO> 101737 </DOCNO>
Philip Hall's Problem On Non-Abelian Splitters


  Philip Hall raised around 1965 the following question which is stated in the
Kourovka Notebook: Is there a non-trivial group which is isomorphic with every
proper extension of itself by itself? We will decompose the problem into two
parts: We want to find non-commutative splitters, that are groups G not= 1 with
Ext(G,G)=1 . The class of splitters fortunately is quite large so that extra
properties can be added to G. We can consider groups G with the following
properties: There is a complete group L with cartesian product L^omega cong G,
Hom(L^omega,S_omega)=0 (S_omega the infinite symmetric group acting on omega)
and End(L,L)=Inn(L) cup {0}. We will show that these properties ensure that G
is a splitter and hence obviously a Hall-group in the above sense. Then we will
apply a recent result from our joint paper math.GR/0009089 which also shows
that such groups exist, in fact there is a class of Hall-groups which is not a
set.

</DOC>
<DOC>
<DOCNO> 70894 </DOCNO>
Pi Pi Scattering and Scalar Mesons in an Effective Chiral Lagrangian


  In this talk I summarize recently proposed mechanisms to understand pi pi
scattering to 1 GeV in an effective chiral Lagrangian. The Lagrangian includes
higher resonances in addition to pions consistently with the chiral symmetry.
Iso-spin zero S-wave partial wave amplitude is reproduced up till about 1.2 GeV
by including a pion self-interaction and resonant pole exchanges of rho,
f0(980) and sigma derived from the effective chiral Lagrangian. The best fit
shows that sigma has a mass of around 560 MeV and a width of about 370 MeV.

</DOC>
<DOC>
<DOCNO> 151607 </DOCNO>
Rotations and e, $\nu$ Propagators, Part I


  Rotation symmetry is less constraining than space-time symmetry. The free
electron propagator is a projection operator that we show can be constructed
from rotation symmetric projection operators. Rotation-based identifications of
time, space, energy, momentum, polarization matrices, and the positron
hypothesis are determined by the constraints that turn rotation symmetric
projection operators into the electron propagator.
  PACS: 11.30.-j, 11.30.Cp, and 03.65.Fd

</DOC>
<DOC>
<DOCNO> 68919 </DOCNO>
Neutrino oscillations in structured matter


  A layered material structure in a monochromatic neutrino beam produces
interference effects that could be used for the measurement of features of the
neutrino mass matrix. The phenomenon would be most useful at high energies.

</DOC>
<DOC>
<DOCNO> 8540 </DOCNO>
Dynamical Origin of Decoherence in Clasically Chaotic Systems


  The decay of the overlap between a wave packet evolved with a Hamiltonian H
and the same state evolved with H}+$\Sigma $ serves as a measure of the
decoherence time $\tau_{\phi}$. Recent experimental and analytical evidence on
classically chaotic systems suggest that, under certain conditions,
$\tau_{\phi}$ depends on H but not on $\Sigma $. By solving numerically a
Hamiltonian model we find evidence of that property provided that the system
shows a Wigner-Dyson spectrum (which defines quantum chaos) and the
perturbation exceeds a crytical value defined by the parametric correlations of
the spectra.

</DOC>
<DOC>
<DOCNO> 80887 </DOCNO>
Laplacian gauge and instantons


  We exhibit the connection between local gauge singularities in the Laplacian
gauge and topological charge, which opens the possibility of studying instanton
excitations without cooling. We describe our version of Laplacian gauge-fixing
for SU(N).

</DOC>
<DOC>
<DOCNO> 40535 </DOCNO>
First Results in Exclusive Radiative Penguin Decays at BABAR


  We present a preliminary measurement of the branching fraction of the
exclusive penguin decay B^0 -> K^*0 gamma using (8.6+/-0.3) x 10^6 B-anti-B
decays BF(B^0 -> K^*0 gamma) = (5.2+/-0.82 (stat.) +/- 0.47 (sys.)) x 10^-5. In
addition we search for the related penguin decays with a lepton pair in the
final state, B^+ -> K^+ l^+l^-, B^0 -> K^*0 l^+l^-. We find no evidence for
these decays in 3.7+/-0.1 x 10^6 B-anti-B decays and set preliminary 90% C.L
upper limits of BF(B^+ -> K^+ e^+ e^-) < 12.5 x 10^{-6}, BF(B^+ -> K^+ mu^+
mu^-) < 8.3 x 10^{-6}, BF(B^0 -> K^*0 e^+ e^-) < 24.1 x 10^{-6}, BF(B^0 -> K^*0
mu^+ mu^-) < 24.5 x 10^{-6}.

</DOC>
<DOC>
<DOCNO> 12389 </DOCNO>
The Bose gas: A subtle many-body problem


  Now that the properties of the ground state of quantum-mechanical many-body
systems (bosons) at low density, $\rho$, can be examined experimentally it is
appropriate to revisit some of the formulas deduced by many authors 4-5 decades
ago. One of these is that the leading term in the energy/particle is $4\pi a
\rho$ where $a$ is the scattering length of the 2-body potential. Owing to the
delicate and peculiar nature of bosonic correlations (such as the strange
$N^{7/5}$ law for charged bosons), four decades of research failed to establish
this plausible formula rigorously. The only previous lower bound for the energy
was found by Dyson in 1957, but it was 14 times too small. The correct
asymptotic formula has recently been obtained jointly with J. Yngvason and this
work will be presented. The reason behind the mathematical difficulties will be
emphasized. A different formula, postulated as late as 1971 by Schick, holds in
two-dimensions and this, too, will be shown to be correct. Another problem of
great interest is the existence of Bose-Einstein condensation, and what little
is known about this rigorously will also be discussed. With the aid of the
methodology developed to prove the lower bound for the homogeneous gas, two
other problems have been successfully addressed. One is the proof (with
Yngvason and Seiringer) that the Gross-Pitaevskii equation correctly describes
the ground state in the `traps' actually used in the experiments. The other is
a very recent proof (with Solovej) that Foldy's 1961 theory of a high density
gas of charged particles correctly describes its ground state energy.

</DOC>
<DOC>
<DOCNO> 83473 </DOCNO>
SimLab 1.1, Software for Sensitivity and Uncertainty Analysis, tool for


  The aim of this paper is to present and describe SimLab 1.1 (Simulation
Laboratory for Uncertainty and Sensitivity Analysis) software designed for
Monte Carlo analysis that is based on performing multiple model evaluations
with probabilistically selected model input. The results of these evaluations
are used to determine both the uncertainty in model predictions and the input
variables that drive this uncertainty. This methodology is essential in
situations where a decision has to be taken based on the model results; typical
examples include risk and emergency management systems, financial analysis and
many others. It is also highly recommended as part of model validation, even
where the models are used for diagnostic purposes, as an element of sound model
building. SimLab allows an exploration of the space of possible alternative
model assumptions and structure on the prediction of the model, thereby testing
both the quality of the model and the robustness of the model based inference.

</DOC>
<DOC>
<DOCNO> 169981 </DOCNO>
Quantum Teleportation and Beam Splitting


  Following the previous paper in which quantum teleportation is rig orously
discussed with coherent entangled states given by beam splittings, we further
discuss two types of models, perfect teleportation model and non-perfect
teleportation model, in general scheme. Then the difference among several
models, i.e., the perfect models and the non-perfect models, is studied. Our
teleportation models are constructed by means of coherent states in some Fock
space with counting measures, so that our model can be treated in the frame of
usual optical communication.

</DOC>
<DOC>
<DOCNO> 119492 </DOCNO>
ASCA Observations of NLS1s: BH Mass Estimation from X-ray Variability


  ASCA observations of Narrow-Line Seyfert 1 galaxies (NLS1s) are presented. We
focus on the black hole size of the NLS1 sources by employing two independent
methods for the mass estimation; one is using X-ray variability, the other is
using a blackbody fit to the soft component. Although the coincidence is not
good for some sources, the mass estimated by these methods ranges from 1e5 to
1e7 solar masses, systematically smaller than those for typical (broad line)
Seyfert 1. We consider the small mass black hole to be the principal cause of
the several extreme characteristics of the NLS1s.

</DOC>
<DOC>
<DOCNO> 71279 </DOCNO>
Signatures of MSSM charged Higgs bosons via chargino-neutralino decay


  We assess the potential of detecting a charged Higgs boson of the MSSM at the
LHC via its decays into a chargino and a neutralino. We focus our attention on
the region of parameter space with $m_{H^{\pm}} > m_t$ and $3 \lsim tan(beta)
\lsim 10$, where identification of the $H^{\pm}$ via other decay modes has
proven to be ineffective. Searching for means to plug this hole, we simulate
the decays $H^{\pm} --> {\tilde\chi}_1^{\pm} {\tilde\chi}_1^0$ and $H^{\pm} -->
{\tilde\chi}_1^{\pm} {\tilde\chi}_2^0,
  {\tilde\chi}_1^{\pm} {\tilde\chi}_3^0$ --- the former can yield a single hard
lepton (from the chargino decay) while the latter can yield three leptons (from
the chargino and neutralino decays). Coupled with the dominant top quark +
charged Higgs boson production mode, the resulting signature is one or three
hard, isolated leptons, substantial missing transverse momentum and a
reconstructed (via a 3-jet invariant mass) top quark. The single lepton channel
is swamped by background processes; however, with suitable cuts, a trilepton
signal emerges. While such a signal suffers from a low number of surviving
events (after cuts) and is dependent on several MSSM input parameters (notably
$M_2$, $\mu$, and slepton masses), it does fill at least some of the void left
by previous investigations.

</DOC>
<DOC>
<DOCNO> 11181 </DOCNO>
Spin-triplet superconducting pairing due to local (Hund's rule, Dirac)


  We discuss general implications of the local spin-triplet pairing among
fermions induced by local ferromagnetic exchange, example of which is the
Hund's rule coupling. The quasiparticle energy and their wave function are
determined for the three principal phases with the gap, which is momentum
independent. We utilize the Bogolyubov-Nambu-De Gennes approach, which in the
case of triplet pairing in the two-band case leads to the four-components wave
function. Both gapless modes and those with an isotropic gap appear in the
quasiparticle spectrum. A striking analogy with the Dirac equation is briefly
explored. This type of pairing is relevant to relativistic fermions as well,
since it reflects the fundamental discrete symmetry-particle interchange. A
comparison with the local interband spin-singlet pairing is also made.

</DOC>
<DOC>
<DOCNO> 119368 </DOCNO>
Proton and Electron Acceleration through Magnetic Turbulence in


  Low frequency electromagnetic turbulence is generated in relativistically
outflowing plasma that sweeps up particles from the surrounding environment.
Electrons are energized by stochastic gyroresonant acceleration with the
turbulence produced by the isotropization of captured protons and charged dust.
Protons are accelerated stochastically by the dust-induced turbulence.
Analytical solutions for the proton and electron energy distributions are
obtained and used to calculate broadband synchrotron emission. The solutions
are compared with generic spectral behavior of blazars and gamma-ray bursts.
Dust captured by a blast wave can generate turbulence that could accelerate
protons to very high energies.

</DOC>
<DOC>
<DOCNO> 12127 </DOCNO>
Electron Interference Effects on the Conductance of Doped Carbon


  We investigate the effects of impurity scattering on the conductance of
metallic carbon nanotubes as a function of the relative separation of the
impurities. First we compute the conductance of a clean (6,6) tube, and the
effect of model gold contacts on this conductance. Then, we compute the effect
of introducing a single, two, and three oxygen atom impurities. We find that
the conductance of a single-oxygen-doped (6,6) nanotube decreases by about 30 %
with respect to that of the perfect nanotube. The presence of a second doping
atom induces strong changes of the conductance which, however, depend very
strongly on the relative position of the two oxygen atoms. We observe regular
oscillations of the conductance that repeat over an O-O distance that
corresponds to an integral number of half Fermi-wavelengths ($m\lambda_F/2$).
These fluctuations reflect strong electron interference phenomena produced by
electron scattering from the oxygen defects whose contribution to the
resistance of the tube cannot be obtained by simply summing up their individual
contributions.

</DOC>
<DOC>
<DOCNO> 121421 </DOCNO>
Bound near-equatorial orbits around neutron stars


  Recent discovery of kilohertz quasi-periodic brightness oscillations of low
mass X-ray binaries (LMXBs) has attracted attention to highly relativistic
periodic motion near accreting neutron stars. Most models proposed so far
involve (almost) inertial motion in the vicinity of the stars' innermost stable
circular orbits. In the present paper we study general-relativistic circular
and eccentric orbits around spinning neutron stars assuming the orbits are
slightly tilted with respect to the stars' equatorial planes. We develop
analytical and numerical techniques for integrating bound timelike geodesics in
fully relativistic neutron star spacetimes obtained by modern numerical codes.
We use equations of state of neutron star matter that span a broad range of
stiffness, while the explored range of masses M > 1.7 M(solar) and spin
frequencies nu_s < 600 Hz is motivated by the observations of LMXBs. We
investigate the general-relativistic effects of periastron advance and nodal
precession in the strong gravitational fields of rotating neutron stars and
compare quantitatively the associated orbital frequencies with the more readily
obtainable frequencies of orbits around Kerr black holes on the one hand, and
low-order post-Newtonian (PN) expansions, on the other. While Kerr results
approximate the periastron advance frequency much better than the PN
expressions, the retrograde torque caused by the high quadrupole moments of the
rotating stars clearly favours the PN approximation in the case of nodal
precession. The methods developed in the present paper are used in the
companion paper to test recent hypotheses regarding the origin of
quasi-periodic oscillations in accreting neutron star sources.

</DOC>
<DOC>
<DOCNO> 39797 </DOCNO>
The $B_c$ mass up to order $\alpha_s^4$


  We evaluate in perturbative QCD, up to order $\alpha_s^4$, the mass of the
$B_c$. We use the so-called 1S-mass in order to improve the convergence of the
perturbative series. Our result is $E(B_c)_{pert} = 6326^{+29}_{-9}$ MeV.
Non-perturbative effects are discussed. A comparison with potential models
seems to be consistent with non-perturbative contributions of the order $ -
(40\div 100)$ MeV.

</DOC>
<DOC>
<DOCNO> 123247 </DOCNO>
The Evolution of Starburst Galaxies


  I review the properties of starburst galaxies in the nearby and distant
universe to decipher their evolution as a distinct extragalactic class. The
physical processes and environments of massive star-formation appear to be
similar out to z = 4, although the modes of triggering are likely quite
different, varied, and still evolving. This is argued with the use of a
structural system that measures the physical conditions of galaxies. This
system provides evidence that starbursts at high-z are triggered by merging,
while nearby starbursts have a host of different triggering mechanisms, none of
which, besides merging, are currently known to exist at z > 2.

</DOC>
<DOC>
<DOCNO> 39970 </DOCNO>
Dyson-Schwinger Equations: Density, Temperature and Continuum Strong QCD


  Continuum strong QCD is the application of models and continuum quantum field
theory to the study of phenomena in hadronic physics, which includes; e.g., the
spectrum of QCD bound states and their interactions; and the transition to, and
properties of, a quark gluon plasma. We provide a contemporary perspective,
couched primarily in terms of the Dyson-Schwinger equations but also making
comparisons with other approaches and models. Our discourse provides a
practitioners' guide to features of the Dyson-Schwinger equations [such as
confinement and dynamical chiral symmetry breaking] and canvasses
phenomenological applications to light meson and baryon properties in cold,
sparse QCD. These provide the foundation for an extension to hot, dense QCD,
which is probed via the introduction of the intensive thermodynamic variables:
chemical potential and temperature. We describe order parameters whose
evolution signals deconfinement and chiral symmetry restoration, and chronicle
their use in demarcating the quark gluon plasma phase boundary and
characterising the plasma's properties. Hadron traits change in an equilibrated
plasma. We exemplify this and discuss putative signals of the effects. Finally,
since plasma formation is not an equilibrium process, we discuss recent
developments in kinetic theory and its application to describing the evolution
from a relativistic heavy ion collision to an equilibrated quark gluon plasma.

</DOC>
<DOC>
<DOCNO> 13920 </DOCNO>
Origin of Spin Ice Behavior in Ising Pyrochlore Magnets with Long Range


  Recent experiments suggest that the Ising pyrochlore magnets ${\rm
Ho_{2}Ti_{2}O_{7}}$ and ${\rm Dy_{2}Ti_{2}O_{7}}$ display qualitative
properties of the ferromagnetic nearest neighbor spin ice model proposed by
Harris {\it et al.}, Phys. Rev. Lett. {\bf 79}, 2554 (1997). The manifestation
of spin ice behavior in these systems {\it despite} the energetic constraints
introduced by the strength and the long range nature of dipole-dipole
interactions, remains difficult to understand. We report here results from a
mean field analysis that shed some light on the origin of spin ice behavior in
(111) Ising pyrochlores. Specifically, we find that there exist a large
frustrating effect of the dipolar interactions beyond the nearest neighbor, and
that the degeneracy established by effective ferromagnetic nearest neighbor
interactions is only very weakly lifted by the long range interactions. Such
behavior only appears beyond a cut-off distance corresponding to $O(10^2)$
nearest neighbor. Our mean field analysis shows that truncation of dipolar
interactions leads to spurious ordering phenomena that change with the
truncation cut-off distance.

</DOC>
<DOC>
<DOCNO> 101035 </DOCNO>
Commutativity up to a factor of bounded operators in complex Hilbert


  We explore commutativity up to a factor, $AB=\lambda BA$, for bounded
operators in a complex Hilbert space. Conditions on the possible values of the
factor $\lambda$ are formulated and shown to depend on spectral properties of
the operators involved. Commutativity up to a unitary factor is considered for
pairs of self-adjoint operators. Examples of nontrivial realizations of such
commutation relations are given.

</DOC>
<DOC>
<DOCNO> 12331 </DOCNO>
Experimental Characterization of the Ising Model in Disordered


  The current status of experiments on the d=2 and d=3 random-exchange and
random-field Ising models, as realized in dilute anisotropic antiferromagnets,
is discussed. Two areas of current investigation are emphasized. For d=3, the
large random field limit is being investigated and equilibrium critical
behavior is being characterized at high magnetic concentrations.

</DOC>
<DOC>
<DOCNO> 10448 </DOCNO>
Edwards measures for powders and glasses


  Can one construct a thermodynamics for compact, slowly moving powders and
grains? A few years ago, Edwards proposed a possible step in this direction,
raising the fascinating perspective that such systems have a statistical
mechanics of their own, different from that of Maxwell, Boltzmann and Gibbs,
allowing us to have some information while still ignoring dynamic details.
Recent developments in the theory of glasses have come to confirm these ideas
within mean-field. In order to go beyond, we explicitly generate Edwards'
measure in a model that, although schematic, is three dimensional. Comparison
of the results thus obtained with the irreversible compaction data shows very
good agreement. The present framework immediately suggests new experimental
checks.

</DOC>
<DOC>
<DOCNO> 100131 </DOCNO>
Supersymmetric Fluid Mechanics


  When anticommuting Grassmann variables are introduced into a fluid dynamical
model with irrotational velocity and no vorticity, the velocity acquires a
nonvanishing curl and the resultant vorticity is described by Gaussian
potentials formed from the Grassmann variables. Upon adding a further specific
interaction with the Grassmann degrees of freedom, the model becomes
supersymmetric.

</DOC>
<DOC>
<DOCNO> 85543 </DOCNO>
Detection of variable frequency signals using a fast chirp transform


  The detection of signals with varying frequency is important in many areas of
physics and astrophysics. The current work was motivated by a desire to detect
gravitational waves from the binary inspiral of neutron stars and black holes,
a topic of significant interest for the new generation of interferometric
gravitational wave detectors such as LIGO. However, this work has significant
generality beyond gravitational wave signal detection.
  We define a Fast Chirp Transform (FCT) analogous to the Fast Fourier
Transform (FFT). Use of the FCT provides a simple and powerful formalism for
detection of signals with variable frequency just as Fourier transform
techniques provide a formalism for the detection of signals of constant
frequency. In particular, use of the FCT can alleviate the requirement of
generating complicated families of filter functions typically required in the
conventional matched filtering process. We briefly discuss the application of
the FCT to several signal detection problems of current interest.

</DOC>
<DOC>
<DOCNO> 100848 </DOCNO>
A Generalization of the Random Assignment Problem


  We give a conjecture for the expected value of the optimal k-assignment in an
m x n-matrix, where the entries are all exp(1)-distributed random variables or
zeros. We prove this conjecture in the case there is a zero-cost
$k-1$-assignment. Assuming our conjecture, we determine some limits, as
$k=m=n\to \infty$, of the expected cost of an optimal n -assignment in an n x
n-matrix with zeros in some region. If we take the region outside a
quarter-circle inscribed in the square matrix, this limit is thus conjectured
to be $\pi^2/24$. We give a computer-generated verification of a conjecture of
Parisi for k=m=n=7 and of a conjecture of Coppersmith and Sorkin for $k\leq 5$.
We have used the same computer program to verify this conjecture also for k=6.

</DOC>
<DOC>
<DOCNO> 39756 </DOCNO>
Search for Resonances Decaying to e^+ jet in e^+ p Interactions at HERA


  The e^+ jet invariant mass spectrum produced in the reaction e^+ p -> e^+ X
has been studied at a center-of-mass energy of 300 GeV. The data were collected
using the ZEUS detector operating at the HERA collider, and correspond to an
integrated luminosity of 47.7 pb^{-1}. The observed mass spectrum is in good
agreement with Standard Model expectations up to an e^+ jet mass of 210 GeV.
Above this mass, some excess is seen. The angular distribution of these events
is typical of high-Q^2 neutral current events and does not give convincing
evidence for the presence of a narrow scalar or vector state. Limits are
presented on the product of cross section and branching ratio for such a state
and are interpreted as limits on leptoquark or R-parity-violating squark
production. Specific leptoquark types are ruled out at 95% confidence level for
coupling strength lambda=0.3 for masses between 150 and 280 GeV.

</DOC>
<DOC>
<DOCNO> 152512 </DOCNO>
On a Covariant Determination of Mass Scales in Warped Backgrounds


  We propose a method of determining masses in brane scenarios which is
independent of coordinate transformations. We apply our method to the scenario
of Randall and Sundrum (RS) with two branes, which provides a solution to the
hierarchy problem. The core of our proposal is the use of covariant equations
and expressing all coordinate quantities in terms of invariant distances. In
the RS model we find that massive brane fields propagate proper distances
inversely proportional to masses that are not exponentially suppressed. The
hierarchy between the gravitational and weak interactions is nevertheless
preserved on the visible brane due to suppression of gravitational interactions
on that brane. The towers of Kaluza-Klein states for bulk fields are observed
to have different spacings on different branes when all masses are measured in
units of the fundamental scale. Ratios of masses on each brane are the same in
our covariant and the standard interpretations. Since masses of brane fields
are not exponentiated, the fundamental scale of higher-dimensional gravity must
be of the order of the weak scale.

</DOC>
<DOC>
<DOCNO> 84601 </DOCNO>
Hyperbolic formulations and numerical relativity: Experiments using


  In order to perform accurate and stable long-time numerical integration of
the Einstein equation, several hyperbolic systems have been proposed. We here
present numerical comparisons between weakly hyperbolic, strongly hyperbolic,
and symmetric hyperbolic systems based on Ashtekar's connection variables. The
primary advantage for using this connection formulation in this experiment is
that we can keep using the same dynamical variables for all levels of
hyperbolicity. Our numerical code demonstrates gravitational wave propagation
in plane symmetric spacetimes, and we compare the accuracy of the simulation by
monitoring the violation of the constraints. By comparing with results obtained
from the weakly hyperbolic system, we observe the strongly and symmetric
hyperbolic system show better numerical performance (yield less constraint
violation), but not so much difference between the latter two. Rather, we find
that the symmetric hyperbolic system is not always the best in numerical
performances.
  This study is the premier to present full numerical simulations using
Ashtekar's variables. We also describe our procedures in detail.

</DOC>
<DOC>
<DOCNO> 69003 </DOCNO>
Leontovich Relations in Thermal Field Theory


  The application of generalized Kramers-Kronig relations, the so-called
Leontovich relations, to thermal field theory is discussed. Medium effects
contained in the full, thermal propagators can easily be taken into account by
this method. As examples the collisional energy loss of a charged particle in a
relativistic plasma and the radiation of energetic photons from a quark-gluon
plasma are considered. Within the leading logarithmic approximation the results
based on the hard thermal loop resummation technique are reproduced easily.
However, the method presented here is more general and provides exact
expressions, which allow in principle non-perturbative calculations.

</DOC>
<DOC>
<DOCNO> 12442 </DOCNO>
Vacancy Formation Energy at High Pressures in Tantalum


  We have computed the variation of the vacancy formation energy with pressure
for Ta. Total energy calculations were performed for 16 and 54 atom supercells
using a mixed basis pseudopotential method which uses pseudo-atomic orbitals
and low energy plane waves as the basis set, within density functional theory
(LDA and GGA). The vacancy formation energy is found to increase from 2.95 eV
at ambient pressures to 6.96 eV at 300 GPa, and the vacancy formation volume
decreases from being 53.4% of the bulk volume per atom at ambient pressure to
19.6% at 300 GPa, for a 54 atom supercell. The structural relaxation energy is
found to increase with pressure from 14% of the vacancy formation energy at
ambient pressure to 16% at 300 GPa.

</DOC>
<DOC>
<DOCNO> 8114 </DOCNO>
Signature of Dynamical Localization in the Lifetime Distribution of


  We consider the effect of dynamical localization on the lifetimes of the
resonances in open wave-chaotic dielectric cavities. We show that dynamical
localization leads to a log-normal distribution of the resonance lifetimes
which scales with the localization length in excellent agreement with the
results of numerical calculations for open rough microcavities.

</DOC>
<DOC>
<DOCNO> 122285 </DOCNO>
On the Origin of Faint Intracluster Starlight in Coma


  Using N-body numerical simulations, we examine possible mechanisms for the
origin of the intracluster starlight features recently discovered in the Coma
cluster of galaxies. We show that tidal interactions of a ``normal'' elliptical
galaxy with a symmetrically distributed dark matter potential do not produce
the observed intracluster starlight features. A head-on collision of two normal
ellipticals does, however, explain the origin of the intracluster features with
surface brightness about 26 mag/arcsec$^2$). Another possible explanation for
the intracluster starlight features is galactic tidal interactions with massive
intracluster substructures. The presence of substructures in Coma with a
density of $\sim$ 0.1 times the density in the center of the galaxy, and with a
total mass about three orders of magnitude larger than the mass of a normal
elliptical galaxy, would account for the observations.

</DOC>
<DOC>
<DOCNO> 118106 </DOCNO>
Magnetized Atmospheres around Accreting Neutron Stars


  We present a detailed investigation of atmospheres around accreting neutron
stars with high magnetic field ($B\gtrsim 10^{12}$ G) and low luminosity
($L\lesssim 10^{33}$ erg/s). We compute the atmospheric structure, intensity
and emergent spectrum for a plane-parallel, pure hydrogen medium by solving the
transfer equations for the normal modes coupled to the hydrostatic and energy
balance equations. The hard tail found in previous investigations for
accreting, non-magnetic neutron stars with comparable luminosity is suppressed
and the X-ray spectrum, although still harder than a blackbody at the star
effective temperature, is nearly planckian in shape. Spectra from accreting
atmospheres, both with high and low fields, are found to exhibit a significant
excess at optical wavelengths above the Rayleigh-Jeans tail of the X-ray
continuum.

</DOC>
<DOC>
<DOCNO> 117251 </DOCNO>
The status and programs of the New Relativity Theory


  A review of the most recent results of the New Relativity Theory is
presented. These include a straightforward derivation of the Black Hole
Entropy-Area relation and its $logarithmic$ corrections; the derivation of the
string uncertainty relations and generalizations ; ; the relation between the
four dimensional gravitational conformal anomaly and the fine structure
constant; the role of Noncommutative Geometry, Negative Probabilities and
Cantorian-Fractal spacetime in the Young's two-slit experiment. We then
generalize the recent construction of the Quenched-Minisuperspace bosonic
$p$-brane propagator in $D$ dimensions ($AACS$ [18]) to the full
multidimensional case involving all $p$-branes : the construction of the
Multidimensional-Particle propagator in Clifford spaces ($C$-spaces) associated
with a nested family of $p$-loop histories living in a target $D$-dim
background spacetime . We show how the effective $C$-space geometry is related
to $extrinsic$ curvature of ordinary spacetime. The motion of rigid
particles/branes is studied to explain the natural $emergence$ of classical
spin. The relation among $C$-space geometry and ${\cal W}$, Finsler Geometry
and (Braided) Quantum Groups is discussed. Some final remarks about the
Riemannian long distance limit of $C$-space geometry are made.

</DOC>
<DOC>
<DOCNO> 13530 </DOCNO>
Magnetization reversal triggered by spin injection in magnetic nanowires


  It is shown that a pulsed current driven through Ni nanowires provokes an
irreversible magnetization reversal at a field distant from the spontaneous
switching field $H_{sw}$ by $\Delta H$ of as much as 40 % of $H_{sw}$. The
state of the magnetization is assessed by magnetoresistive measurements carried
out on single, isolated nanowires. The reversible part of the magnetization
follows that of a uniform rotation. The switching occurs between the two states
accessible otherwise by normal field ramping. $\Delta H$ is studied as a
function of the angle between the applied field and the wire, and also of the
direction of the pulsed current. The results are interpreted in terms of
spin-flip transfer from the spin-polarized current to the magnetization, while
the switching is approximated by a curling reversal mode.

</DOC>
<DOC>
<DOCNO> 178959 </DOCNO>
Microscopic structure of fundamental excitations in N=Z nuclei


  Excitation energies of the $T$=1 states in even-even as well as $T$=0 and
$T$=1 states in odd-odd $N$=$Z$ nuclei are calculated within the mean-field
approach. It is shown that the underlying structure of these states can be
determined in a consistent manner only when both isoscalar and isovector
pairing collectivity as well as isospin projection, treated within the
iso-cranking approximation, are taken into account. In particular, in odd-odd
$N$=$Z$ nuclei, the interplay between quasiparticle excitations (relevant for
the case of $T$=0 states) and iso-rotations (relevant for the case of $T$=1
states) explains the near-degeneracy of these fundamental excitations.

</DOC>
<DOC>
<DOCNO> 170464 </DOCNO>
Schmidt number witnesses and bound entanglement


  The Schmidt number of a mixed state characterizes the minimum Schmidt rank of
the pure states needed to construct it. We investigate the Schmidt number of an
arbitrary mixed state by constructing a Schmidt number witness that detects it.
We present a canonical form of such witnesses and provide constructive methods
for their optimization. Finally, we present strong evidence that all bound
entangled states with positive partial transpose in two qutrit systems have
Schmidt number 2.

</DOC>
<DOC>
<DOCNO> 11551 </DOCNO>
Instabilities and disorder-driven first-order transition of the vortex


  Transport studies in a Corbino disk geometry suggest that the Bragg glass
phase undergoes a first-order transition into a disordered solid. This
transition shows a sharp reentrant behavior at low fields. In contrast, in the
conventional strip configuration, the phase transition is obscured by the
injection of the disordered vortices through the sample edges, which results in
the commonly observed vortex instabilities and smearing of the peak effect in
NbSe2 crystals. These features are found to be absent in the Corbino geometry,
in which the circulating vortices do not cross the sample edges.

</DOC>
<DOC>
<DOCNO> 84257 </DOCNO>
On Schwarzschild-Like Solutions in Curvature-Quadratic Gravity


  Partial results are obtained for Schwarzschild- like solutions in a gravity
theory with action density (-g)^(1/2)[Rik^2+bR^2]. A seven parameter family of
implicit solutions is found. A number of explicit solutions are also exhibited.

</DOC>
<DOC>
<DOCNO> 12037 </DOCNO>
Relevant boundary perturbations of CFT: A case study


  We consider simple CFT models which contain massless bosons, or massless
fermions or a supersymmetric combination of the two, on the strip. We study the
deformations of these models by relevant boundary operators. In particular, we
work out the details for a boundary operator with a quadratic dependence on the
fields and argue that some of our results can be extended to a more general
situation. In the fermionic models, several subtleties arise due to the
doubling of zero modes at the UV fixed point and a ``GSO projected'' RG flow.
We attempt to resolve these issues and to discuss how bulk symmetries are
realised along the flow. We end with some speculations on possible string
theory applications of these results.

</DOC>
<DOC>
<DOCNO> 102317 </DOCNO>
Statistical analysis of the inhomogeneous telegrapher's process


  We consider a problem of estimation for the telegrapher's process on the
line, say X(t), driven by a Poisson process with non constant rate. It turns
out that the finite-dimensional law of the process X(t) is a solution to the
telegraph equation with non constant coefficients. We give the explicit law
P(theta) of the process X(t) for a parametric class of intensity functions for
the Poisson process. We propose an estimator for the parameter theta of
P(theta) and we discuss its properties as a first attempt to apply statistics
to these models.

</DOC>
<DOC>
<DOCNO> 100474 </DOCNO>
On p-Adic Functional Integration


  p-Adic generalization of the Feynman path integrals in quantum mechanics is
considered. The probability amplitude for a particle in a constant field is
calculated. Path integrals over p-adic space have the same form as those over
R.

</DOC>
<DOC>
<DOCNO> 151156 </DOCNO>
How massless are massless fields in $AdS_d$


  Massless fields of generic Young symmetry type in $AdS_d$ space are analyzed.
It is demonstrated that in contrast to massless fields in Minkowski space whose
physical degrees of freedom transform in irreps of $o(d-2)$ algebra, $AdS$
massless mixed symmetry fields reduce to a number of irreps of $o(d-2)$
algebra. From the field theory perspective this means that not every massless
field in flat space admits a deformation to $AdS_d$ with the same number of
degrees of freedom, because it is impossible to keep all of the flat space
gauge symmetries unbroken in the AdS space. An equivalent statement is that,
generic irreducible AdS massless fields reduce to certain reducible sets of
massless fields in the flat limit. A conjecture on the general pattern of the
flat space limit of a general $AdS_d$ massless field is made. The example of
the three-cell ``hook'' Young diagram is discussed in detail. In particular, it
is shown that only a combination of the three-cell flat-space field with a
graviton-like field admits a smooth deformation to $AdS_d$.

</DOC>
<DOC>
<DOCNO> 120784 </DOCNO>
Relativistic Iron Emission and Disk Reflection in Galactic Microquasar


  We report evidence for an Fe K-alpha fluorescence line feature and disk
reflection in the Very High, High, and Low State X-ray spectra of the galactic
microquasar XTE J1748-288 during its June~1998 outburst. Spectral analyses are
made on data gathered throughout the outburst by the Rossi X-ray Timing
Explorer Proportional Counter Array. Gaussian line, relativistic disk emission
line, and ionized disk reflection models are fit to the data. In the Very High
State the line profile appears strongly redshifted, consistent with disk
emission from the innermost stable orbits around a maximally rotating Kerr
black hole. In the High State the line profile is less redshifted and
increasingly prominent. The Low State line profile is very strong (~0.5 keV
equivalent width) and centered at 6.7 +/- 0.10 keV; disk line emission model
fits indicate that the inner edge of the disk fluctuates between ~20 and ~100
gravitational radii in this state. The disk reflection fraction is traced
through the outburst; reflection from an ionized disk is preferred in the VHS
and HS, and reflection from a relatively neutral disk is preferred in the LS.
We discuss the implications of our findings for the binary system dynamics and
accretion flow geometry in XTE J1748-288.

</DOC>
<DOC>
<DOCNO> 7867 </DOCNO>
Localization-delocalization transition in disordered systems with a


  Using the supersymmetry technique, we study the localization-delocalization
transition in quasi-one-dimensional non-Hermitian systems with a direction. In
contrast to chains, our model captures the diffusive character of carriers'
motion at short distances. We calculate the joint probability of complex
eigenvalues and some other correlation functions. We find that the transition
is abrupt and occurs as a result of an interplay between two saddle-points in
the free energy functional.

</DOC>
<DOC>
<DOCNO> 70908 </DOCNO>
Reconciling neutrino anomalies in a simple four-neutrino scheme with


  We propose a simple extension of the MSSM based on extra compact dimensions
which includes an $SU(2) \otimes U(1)$ singlet superfield. The fermion present
in this superfield is the sterile neutrino, which combines with one linear
combination of $\nu_e-\nu_{\mu}-\nu_{\tau}$ to form a Dirac pair whose mass
accounts for the LSND anomaly. Its small mass can be ascribed to a volume
suppression factor associated with extra compact dimensions. On the other hand
the sterile neutrino scalar partner can trigger the spontaneous violation of
R-parity, thereby inducing the necessary mass splittings to fit also the solar
and atmospheric neutrino data. Thus the model can explain all neutrino
oscillation data. It leads to four predictions for the neutrino oscillation
parameters and implies that the atmospheric neutrino problem must include at
least some $\nu_{\mu} \to \nu_s$ oscillations, which will be testable in the
near future. Moreover it also predicts that the lightest supersymmetric
particle (LSP) decays visibly via lepton number violating modes, which could be
searched for at present and future accelerators.

</DOC>
<DOC>
<DOCNO> 11906 </DOCNO>
Criticality and Superfluidity in liquid He-4 under Nonequilibrium


  We review a striking array of recent experiments, and their theoretical
interpretations, on the superfluid transition in $^4$He in the presence of a
heat flux, $Q$. We define and evaluate a new set of critical point exponents.
The statics and dynamics of the superfluid-normal interface are discussed, with
special attention to the role of gravity. If $Q$ is in the same direction as
gravity, a self-organized state can arise, in which the entire sample has a
uniform reduced temperature, on either the normal or superfluid side of the
transition. Finally, we review recent theory and experiment regarding the heat
capacity at constant $Q$. The excitement that surrounds this field arises from
the fact that advanced thermometry and the future availability of a
microgravity experimental platform aboard the International Space Station will
soon open to experimental exploration decades of reduced temperature that were
previously inaccessible.

</DOC>
<DOC>
<DOCNO> 120868 </DOCNO>
Emergence of power-law correlation in 1-dimensional self-gravitating


  A new phase of temporal evolution of the one-dimensional self-gravitating
system is numerically discovered. Fractal structure is dynamically created from
non-fractal initial conditions. Implication to astrophysics and mathematical
physics is discussed.

</DOC>
<DOC>
<DOCNO> 9079 </DOCNO>
Temperature Dependent Scattering Rates at the Fermi Surface of Optimally


  For optimally doped Bi 2212, scattering rates in the normal state are found
to have a linear temperature dependence over most of the Fermi surface. In the
immediate vicinity of the (1,0) point, the scattering rates are nearly constant
in the normal state, consistent with models in which scattering at this point
determines the c-axis transport. In the superconducting state, the scattering
rates away from the nodal direction appear to level off and become
temperature-independent.

</DOC>
<DOC>
<DOCNO> 14089 </DOCNO>
The re-examined phenomenological phase transitions theory for


  The existence of the linear on the order parameter term of the thermodynamic
functions expansion near the critical point is justified. The criticism of the
arguments, used for the rejection of the odd-power expansion terms of the
ferromagnets thermodynamic functions is presented. It is shown, that taking
into account the linear term in expansion one achieves the consentency with
experimental data on the magnetization behavior near the transition temperature
in ferromagnets.

</DOC>
<DOC>
<DOCNO> 72291 </DOCNO>
Low Energy Pion-Hyperon Interaction


  We study the low energy pion-hyperon interaction considering effective
non-linear chiral invariant Lagrangians including pions, rho mesons, hyperons
and corresponding resonances. Then we calculate the S- and P-wave phase-shifts,
total cross sections, angular distributions and polarizations for the momentum
in the center-of-mass frame up to k=400 MeV. With these results we discuss the
CP violation in the csi-> pi-lambda and omega-> pi-csi weak decays.

</DOC>
<DOC>
<DOCNO> 101062 </DOCNO>
Limiting values of rational functions at the points of discontinuity


  In the present article we describe a class of algebraic curves on which
rational functions of two arguments may reach all their possible limiting
values. We also solve a similar question for functions that can be represented
as a uniform limit of a sequence of bounded rational functions.

</DOC>
<DOC>
<DOCNO> 83359 </DOCNO>
Estimators for Stochastic ``Unification-Based'' Grammars


  Log-linear models provide a statistically sound framework for Stochastic
``Unification-Based'' Grammars (SUBGs) and stochastic versions of other kinds
of grammars. We describe two computationally-tractable ways of estimating the
parameters of such grammars from a training corpus of syntactic analyses, and
apply these to estimate a stochastic version of Lexical-Functional Grammar.

</DOC>
<DOC>
<DOCNO> 83345 </DOCNO>
Aspects of Pattern-Matching in Data-Oriented Parsing


  Data-Oriented Parsing (dop) ranks among the best parsing schemes, pairing
state-of-the art parsing accuracy to the psycholinguistic insight that larger
chunks of syntactic structures are relevant grammatical and probabilistic
units. Parsing with the dop-model, however, seems to involve a lot of CPU
cycles and a considerable amount of double work, brought on by the concept of
multiple derivations, which is necessary for probabilistic processing, but
which is not convincingly related to a proper linguistic backbone. It is
however possible to re-interpret the dop-model as a pattern-matching model,
which tries to maximize the size of the substructures that construct the parse,
rather than the probability of the parse. By emphasizing this memory-based
aspect of the dop-model, it is possible to do away with multiple derivations,
opening up possibilities for efficient Viterbi-style optimizations, while still
retaining acceptable parsing accuracy through enhanced context-sensitivity.

</DOC>
<DOC>
<DOCNO> 170006 </DOCNO>
On Teleportation of a Completely Unknown State of Relativistic Photon


  The process of teleportation of a completely unknown single-photon
relativistic state is considered. Analysis of the relativistic case reveals
that the teleportation as it is understood in the non-relativistic quantum
mechanics is impossible if no {\it a priori} information on the state to be
teleported is available. It is only possible to speak of the amplitude of the
propagation of the field (taking into account the measurement procedure) since
the existence of a common vacuum state together with the microcausality
principle (the field operators commutation relations) make the concept of the
propagation amplitude for the individual subsystems physically meaningless.
When partial {\it a priori} information is available (for example, only the
polarization state of the photon is unknown while its spatial state is
specified beforehand), the teleportation does become possible in the
relativistic case. In that case the {\it a priori} information can be used to
``label'' the identical particles to make them effectively distinguishable.

</DOC>
<DOC>
<DOCNO> 10674 </DOCNO>
Stability of d-wave superconductivity in the t-J model


  We use a recently developed technique, which allows to perform few Lanczos
steps on a given wavefunction even for large system sizes, to investigate the
$t{-}J$ model in the physical parameter region and to check the stability of
the BCS d-wave variational wavefunction. Our statistical Lanczos algorithm,
which extends and improves the one Lanczos step, has been extensively tested on
the small L=18 sites cluster where many Lanczos iterations can be performed
exactly. In this case, at doping $\delta\sim 10%$ the BCS wavefunction
represents a very good initial state to achieve extremely accurate energies and
correlation functions with few Lanczos iterations. For large sizes ($L\le 98$)
the behavior is similar: the low-energy d-wave order parameter $P_d$ is weakly
affected by a couple of Lanczos iterations in the low doping $\delta\sim 10%$
region, whereas the energy is considerably lowered. As a further test of our
calculation we have computed the variance of the Hamiltonian $\Delta E_p=(<
\hat{H}^2 >-< \hat{H} >^2)/L^2$ on the BCS wavefunction with $p=0,1,2$ Lanczos
steps. For large $p$, when the Lanczos algorithm converges to the exact ground
state, the variance vanishes exponentially with increasing $p$. The remarkable
reduction of the variance, observed for $p=1,2$ Lanczos steps even for the
largest lattice size considered, suggests a smooth and rapid convergence to the
exact ground state. These results support the existence of off-diagonal
long-range d-wave superconducting order in the two-dimensional $t{-}J$ model.

</DOC>
<DOC>
<DOCNO> 68410 </DOCNO>
Critical couplings for chiral symmetry breaking via instantons


  Using an instanton effective action formalism, we compute the critical
coupling for the nonperturbative formation of a dynamical mass via instantons
in non-Abelian gauge theories with N_f massless fermions. Only continuous phase
transitions are considered. For large values of N_f the critical couplings are
found to be much smaller than the equivalent critical couplings obtained from
gauge exchange calculations in the ladder approximation.

</DOC>
<DOC>
<DOCNO> 13315 </DOCNO>
Using a Fermionic Ensemble of Systems to Determine Excited States


  We discuss a new numerical method for the determination of excited states of
a quantum system using a generalization of the Feynman-Kac formula. The method
relies on introducing an ensemble of non-interacting identical systems with a
fermionic statistics imposed on the systems as a whole, and on determining the
ground state of this fermionic ensemble by taking the large time limit of the
Euclidean kernel. Due to the exclusion principle, the ground state of an
$n$-system ensemble is realized by the set of individual systems occupying
successively the $n$ lowest states, all of which can therefore be sampled in
this way. To demonstrate how the method works, we consider a one-dimensional
oscillator and a chain of harmonically coupled particles.

</DOC>
<DOC>
<DOCNO> 80987 </DOCNO>
Unquenched QCD simulation results


  The recent progress on unquenched QCD simulations is critically reviewed.
After some discussions on problems and subtleties in unquenched simulations,
hadron spectra obtained from both quenched and unquenched simulations are
compared among various gauge and quark actions. It is found that the Edinburgh
plot does not agree in the continuum limit between Wilson and KS quark actions
even in quenched QCD. Dynamical quark effects on hadron spectra, in particular,
on meson masses are then presented for Wilson-type quark actions. Finally
dynamical quark effects on other quantities such as the topological
susceptibility and the flavor-singlet meson mass are discussed.

</DOC>
<DOC>
<DOCNO> 9596 </DOCNO>
Extended corresponding-states behavior for particles with variable range


  We propose an extension of the law of corresponding states that can be
applied to systems - such as colloidal suspensions - that have widely different
ranges of attractive interactions. We argue that, for such systems, the
``reduced'' second virial coefficient is a convenient parameter to quantify the
effective range of attraction. This procedure allows us to give a simple
definition of the effective range of attraction of potentials with different
functional forms. The advantage of the present approach is that it allows us to
estimate the relative location of the liquid-vapor and solid-fluid coexistence
curves exclusively on basis of the knowledge of the pair-potential.

</DOC>
<DOC>
<DOCNO> 8757 </DOCNO>
Derivation of Boltzmann Equiation in Closed-Time-Path Formalism


  A systematic derivation of Boltzmann equation is presented in the framework
of closed-time-path formalism. Introducing a new type of probe, the expectation
value of number operator is calculated as a functional of source. Then solving
for the source by inverting the relation, the equation of motion for number is
obtained when the source is removed, and it turns out to be the Boltzmann
equation. The inversion formula is used in the course of derivation.

</DOC>
<DOC>
<DOCNO> 169578 </DOCNO>
CSL Collapse Model And Spontaneous Radiation: An Update


  A brief review is given of the Continuous Spontaneous Localization (CSL)
model in which a classical field interacts with quantized particles to cause
dynamical wavefunction collapse. One of the model's predictions is that
particles "spontaneously" gain energy at a slow rate. When applied to the
excitation of a nucleon in a Ge nucleus, it is shown how a limit on the
relative collapse rates of neutron and proton could be obtained, and a rough
estimate is made from data. When applied to the spontaneous excitation of 1s
electrons in Ge, by a more detailed analysis of more accurate data than
previously given, an updated limit is obtained on the relative collapse rates
of the electron and proton, suggesting that the coupling of the field to
electrons and nucleons is mass proportional.

</DOC>
<DOC>
<DOCNO> 151060 </DOCNO>
Dual Projection and Selfduality in Three Dimensions


  We discuss the notion of duality and selfduality in the context of the dual
projection operation that creates an internal space of potentials. Contrary to
the prevailing algebraic or group theoretical methods, this technique is
applicable to both even and odd dimensions. The role of parity in the kernel of
the Gauss law to determine the dimensional dependence is clarified. We derive
the appropriate invariant actions, discuss the symmetry groups and their proper
generators. In particular, the novel concept of duality symmetry and
selfduality in Maxwell theory in (2+1) dimensions is analysed in details. The
corresponding action is a 3D version of the familiar duality symmetric
electromagnetic theory in 4D. Finally, the duality symmetric actions in the
different dimensions constructed here manifest both the SO(2) and $Z_2$
symmetries, contrary to conventional results.

</DOC>
<DOC>
<DOCNO> 150605 </DOCNO>
Chiral Gauge Anomalies on Noncommutative R^4


  We discuss the noncommutative counterparts of chiral gauge theories and
compute the associated anomalies.

</DOC>
<DOC>
<DOCNO> 178922 </DOCNO>
Review of N N Interaction from Lattice QCD


  Historically, lattice studies of QCD have concentrated on understanding the
properties and structure of an isolated hadron. Recently, there have efforts at
understanding the interactions between hadrons. In this talk I will review two
approaches to this problem.

</DOC>
<DOC>
<DOCNO> 84738 </DOCNO>
Present limits to cosmic bubbles from the COBE-DMR three point


  The existence of large scale voids in several galaxy surveys suggests the
occurence of an inflationary first order phase transition. This process
generates primordial bubbles that, before evolving into the present voids,
leave at decoupling a non-Gaussian imprint on the CMB. I this paper we evaluate
an analytical expression of the collapsed three point correlation function from
the bubble temperature fluctuations. Comparing the results with COBE-DMR
measures, we obtain upper limits on the allowed non-Gaussianity and hence on
the bubble parameters.

</DOC>
<DOC>
<DOCNO> 102401 </DOCNO>
Algebraic Quantum Field Theory: A Status Report


  Algebraic quantum field theory is an approach to relativistic quantum
physics, notably the theory of elementary particles, which complements other
modern developments in this field. It is particularly powerful for structural
analysis but has also proven to be useful in the rigorous treatment of models.
In this contribution a non-technical survey is given with emphasis on
interesting recent developments and future perspectives. Topics covered are the
relation between the algebraic approach and conventional quantum field theory,
its significance for the resolution of conceptual problems (such as the
revision of the particle concept) and its role in the characterization and
possibly also construction of quantum field theories with the help of modular
theory. The algebraic approach has also shed new light on the treatment of
quantum field theories on curved spacetime and made contact with recent
developments in string theory (algebraic holography).

</DOC>
<DOC>
<DOCNO> 13217 </DOCNO>
Tunneling conductance of SIN junctions with different gap symmetries and


  We theoretically investigate the effect of various symmetries of the
superconducting order parameter Delta(omega) on the normalized tunneling
conductance of SIN junctions by directly solving the real-axis Eliashberg
equations (EEs) for a half-filled infinite band, with the simplifying
assumption mu*=0. We analyze six different symmetries of the order parameter:
s, d, s+id, s+d, extended s and anisotropic s, by assuming that the spectral
function alpha^{2}F(Omega) contains an isotropic part alpha^{2}F(Omega)_{is}
and an anisotropic one, alpha^{2}F(Omega)_{an}, such that
alpha^{2}F(Omega)_{an} = g alpha^{2}F(Omega)_{is}, where g is a constant.
  We compare the resulting conductance curves at T=2 K to those obtained by
analytical continuation of the imaginary-axis solution of the EEs, and we show
that the agreement is not equally good for all symmetries. Then, we discuss the
effect of non-magnetic impurities on the theoretical tunneling conductance
curves at T=4 K for all the symmetries considered.
  Finally, as an example, we apply our calculations to the case of
optimally-doped high-T_{c} superconductors (HTSC). Surprisingly, although the
possibility of explaining the very complex phenomenology of HTSC is probably
beyond the limits of the Eliashberg theory, the comparison of the theoretical
curves calculated at T=4 K with the experimental ones obtained in various
optimally-doped copper-oxides gives fairly good results.

</DOC>
<DOC>
<DOCNO> 71907 </DOCNO>
Diagnostics of quark-gluon plasma in ultrarelativistic heavy ion


  We analyze the possibilities for studying properties of dense QCD-matter,
created in ultrarelativistic nuclear collisions, by hard QCD-production
processes, so-called "hard" probes -- heavy quarkonia, hard jets, high mass
dimuons. Special attention is paid to the potential of coming heavy ion
experiments on Large Hadron Collider to observe the rescattering and energy
losses of hard partons in quark-gluon plasma.

</DOC>
<DOC>
<DOCNO> 13254 </DOCNO>
Mean-atom-trajectory model for the velocity autocorrelation function of


  We present a model for the motion of an average atom in a liquid or
supercooled liquid state and apply it to calculations of the velocity
autocorrelation function $Z(t)$ and diffusion coefficient $D$. The model
trajectory consists of oscillations at a distribution of frequencies
characteristic of the normal modes of a single potential valley, interspersed
with position- and velocity-conserving transits to similar adjacent valleys.
The resulting predictions for $Z(t)$ and $D$ agree remarkably well with MD
simulations of Na at up to almost three times its melting temperature. Two
independent processes in the model relax velocity autocorrelations: (a)
dephasing due to the presence of many frequency components, which operates at
all temperatures but which produces no diffusion, and (b) the transit process,
which increases with increasing temperature and which produces diffusion.
Because the model provides a single-atom trajectory in real space and time,
including transits, it may be used to calculate all single-atom correlation
functions.

</DOC>
<DOC>
<DOCNO> 169877 </DOCNO>
Quantum Bit Escrow


  Unconditionally secure bit commitment and coin flipping are known to be
impossible in the classical world. Bit commitment is known to be impossible
also in the quantum world. We introduce a related new primitive - {\em quantum
bit escrow}. In this primitive Alice commits to a bit $b$ to Bob. The
commitment is {\em binding} in the sense that if Alice is asked to reveal the
bit, Alice can not bias her commitment without having a good probability of
being detected cheating. The commitment is {\em sealing} in the sense that if
Bob learns information about the encoded bit, then if later on he is asked to
prove he was playing honestly, he is detected cheating with a good probability.
Rigorously proving the correctness of quantum cryptographic protocols has
proved to be a difficult task. We develop techniques to prove quantitative
statements about the binding and sealing properties of the quantum bit escrow
protocol.
  A related primitive we construct is a quantum biased coin flipping protocol
where no player can control the game, i.e., even an all-powerful cheating
player must lose with some constant probability, which stands in sharp contrast
to the classical world where such protocols are impossible.

</DOC>
<DOC>
<DOCNO> 68835 </DOCNO>
Further Contents of Einstein's E = mc^{2}


  The energy-mass content of Einstein's E = mc^{2} is well known. For a fixed
value of mass, E = mc^{2} is an energy-momentum relation which takes the form E
= \sqrt{m^{2} + p^{2}}. This relation was formulated in 1905 for point
particles. Since then, particles have become more complicated. They have
internal space-time structures. Massive particles carry the package of internal
variables including mass, spin and quarks, while massless particles have the
package containing helicity, gauge variables, and partons. The question then is
whether these two different packages of variables can be unified into one
single covariant package as E = mc^{2} does for the energy-momentum relations
for massive and massless particles. The answer to this question is YES.

</DOC>
<DOC>
<DOCNO> 84207 </DOCNO>
General analysis of self-dual solutions for the


  The solutions of the Einstein-Maxwell-Chern-Simons theory are studied in
(1+2) dimensions with the self-duality condition imposed on the Maxwell field.
We give a closed form of the general solution which is determined by a single
function having the physical meaning of the quasilocal angular momentum of the
solution. This function completely determines the geometry of spacetime, also
providing the direct computation of the conserved total mass and angular
momentum of the configurations.

</DOC>
<DOC>
<DOCNO> 122709 </DOCNO>
Cosmological Parameter Estimation from CMB Experiments


  I review the general aspects of cosmological parameter estimation from
observations of the cosmic microwave background (CMB) temperature anisotropies
in the framework of inflationary adiabatic models. The most recent CMB datasets
are starting to give good constraints on the relevant parameters of
inflationary adiabatic models. They point toward a model consistent with the
basic predictions of inflation: a nearly flat universe, with a nearly scale
invariant spectrum of primordial fluctuation.

</DOC>
<DOC>
<DOCNO> 84553 </DOCNO>
Geometric Cone Surfaces and (2+1)- Gravity coupled to Particles


  We introduce the (2+1)-spacetimes with compact space of genus g and with r
gravitating particles which arise by ``Minkowskian suspensions of flat or
hyperbolic cone surfaces'', by ``distinguished deformations'' of hyperbolic
suspensions and by ``patchworking'' of suspensions. Similarly to the
matter-free case, these spacetimes have nice properties with respect to the
canonical Cosmological Time Function. When the values of the masses are
sufficiently large and the cone points are suitably spaced, the distinguished
deformations of hyperbolic suspensions determine a relevant open subset of the
full parameter space; this open subset is homeomorphic to the product of an
Euclidean space of dimension 6g-6+2r with an open subset of the Teichm\"uller
Space of Riemann surfaces of genus g with r punctures. By patchworking of
suspensions one can produce examples of spacetimes which are not distinguished
deformations of any hyperbolic suspensions, although they have the same masses;
in fact, we will guess that they belong to different connected components of
the parameter space.

</DOC>
<DOC>
<DOCNO> 72203 </DOCNO>
Unitarized pseudoscalar meson scattering amplitudes in three flavor


  The three flavor linear sigma model is studied as a ``toy model'' for
understanding the role of possible light scalar mesons in the \pi \pi, \pi K
and \pi \eta scattering channels. The approach involves computing the tree
level partial wave amplitude for each channel and unitarizing by a simple
K-matrix prescription which does not introduce any new parameters. If the
renormalizable version of the model is used there is only one free parameter.
While this highly constrained version has the right general structure to
explain \pi \pi scatteirng, it is ``not quite'' right. A reasonable fit can be
made if the renormalizability (for the {\it effective} Lagrangian) is relaxed
while chiral symmetry is maintained. The occurence of a Ramsauer Townsend
mechanism for the f_0(980) region naturally emerges. The effect of
unitarization is very important and leads to ``physical'' masses for the scalar
nonet all less than about 1 GeV. The a_0(1450) and K_0^*(1430) appear to be
``outsiders'' in this picture and to require additional fields. Comparison is
made with a scattering treatment using a more general non-linear sigma model
approach. In addition some speculative remarks and a highly simplified larger
toy model are devoted to the question of the quark substructure of the light
scalar mesons.

</DOC>
<DOC>
<DOCNO> 72047 </DOCNO>
The photon structure and exclusive production of vector mesons in


  The process of exclusive vector meson production (gamma gamma to J/psi rho^0)
is studied for almost real photons. This process may be reduced to
photoproduction of J/psi off the rho^0 meson. We discuss the possibility of
extracting the gluon distribution of rho^0 and of the photon from such
measurement. Predictions are also given for the reaction (e+e- to e+ e- J/psi
rho^0) for various e+e- cms energies typical for LEP and for the future linear
colliders.

</DOC>
<DOC>
<DOCNO> 117420 </DOCNO>
Mapping the Evolution of High Redshift Dusty Galaxies with Submillimeter


  Direct submm imaging has recently revealed the 850-micron background to be
mostly composed of a population of distant ultraluminous infrared galaxies, but
identifying the optical/NIR counterparts to these sources has proved difficult
due to the poor submm spatial resolution. However, the proportionality of both
cm and submm data to the star formation rate suggests that high resolution
radio continuum maps with subarcsecond positional accuracy can be exploited to
locate submm sources. In this paper we present results from a targeted SCUBA
survey of micro-Jansky radio sources in the flanking fields of the Hubble Deep
Field. Even with relatively shallow 850-micron SCUBA observations (>6 mJy at
3-sigma), we were successful at making submm detections of optical/NIR-faint
(I>24 and K~21-22) radio sources, and our counts closely match the bright
counts from submm surveys. Redshift estimates can be made from the ratio of the
submm flux to the radio flux across the 100 GHz break in the spectral energy
distribution. This millimetric redshift estimation places the bright submm
population at z=1-3 where it forms the high redshift tail of the faint radio
population. The star formation rate density (SFRD) due to ultraluminous
infrared galaxies increases by more than two orders of magnitude from z~0 to
z~1-3. The SFRD at high redshift inferred from our >6 mJy submm observations is
comparable to that observed in the UV/optical. (Abridged)

</DOC>
<DOC>
<DOCNO> 151383 </DOCNO>
A Canonical Formalism For Lagrangians With Nonlocality Of Finite Extent


  I consider Lagrangians which depend nonlocally in time but in such a way that
there is no mixing between times differing by more than some finite value
$\Delta t$. By considering these systems as the limits of ever higher
derivative theories I obtain a canonical formalism in which the coordinates are
the dynamical variable from $t$ to $t + {\Delta t}$. A simple formula for the
conjugate momenta is derived in the same way. This formalism makes apparent the
virulent instability of this entire class of nonlocal Lagrangians. As an
example, the formalism is applied to a nonlocal analog of the harmonic
oscillator.

</DOC>
<DOC>
<DOCNO> 170420 </DOCNO>
Optical tests of quantum nonlocality: from EPR-Bell tests towards


  Past, present and future experimental tests of quantum nonlocality are
discussed. Consequences of assuming that the state-vector collapse is a real
physical phenomenon in space-time are developed. These lead to experiments
feasible with today's technology.

</DOC>
<DOC>
<DOCNO> 169711 </DOCNO>
Unitary relation between a harmonic oscillator of time-dependent


  The unitary operator which transforms a harmonic oscillator system of
time-dependent frequency into that of a simple harmonic oscillator of different
time-scale is found, with and without an inverse-square potential. It is shown
that for both cases, this operator can be used in finding complete sets of wave
functions of a generalized harmonic oscillator system from the well-known sets
of the simple harmonic oscillator. Exact invariants of the time-dependent
systems can also be obtained from the constant Hamiltonians of unit mass and
frequency by making use of this unitary transformation. The geometric phases
for the wave functions of a generalized harmonic oscillator with an
inverse-square potential are given.

</DOC>
<DOC>
<DOCNO> 71781 </DOCNO>
Restricted flavor structure of soft SUSY breaking trilinear couplings


  We analyze the flavor structure of the trilinear couplings in the different
theoretical models of SUSY breaking. We generically obtain A_{ij}= A^L_i +
A^R_j in all the models examined. In fact, this is the rigorous form when SUSY
breaking effects appear through the Kahler metric of chiral fields or through
wave-function renormalization. Indeed, the low-energy phenomenological
requirements from the absence of charge and color breaking minima and the
measurements in flavor changing neutral current (FCNC) observables strongly
favor this restricted form of the trilinear matrices. As a straightforward
consequence, the number of unknown parameters associated with the trilinear
couplings is decreased in a factor of 2.

</DOC>
<DOC>
<DOCNO> 12664 </DOCNO>
Simple Analytical Particle and Kinetic Energy Densities for a Dilute


  We derive simple analytical expressions for the particle density $\rho(r)$
and the kinetic energy density $\tau(r)$ for a system of noninteracting
fermions in a $d-$dimensional isotropic harmonic oscillator potential. We test
the Thomas-Fermi (TF, or local-density) approximation for the functional
relation $\tau[\rho]$ using the exact $\rho(r)$ and show that it locally
reproduces the exact kinetic energy density $\tau(r)$, {\it including the shell
oscillations,} surprisingly well everywhere except near the classical turning
point. For the special case of two dimensions (2D), we obtain the unexpected
analytical result that the integral of $\tau_{TF}[\rho(r)]$ yields the {\it
exact} total kinetic energy.

</DOC>
<DOC>
<DOCNO> 152629 </DOCNO>
Anti-de-Sitter D-branes


  We study D-branes of the ${SL(2,\bR)}$ WZW model, and of its discrete
orbifolds. Gluing the currents by group automorphisms leads to three types of
D-branes: two-dimensional hyperbolic planes ($H_2$), de Sitter branes (dS$_2$),
or anti-de-Sitter branes (AdS$_2$). We explain that the dS$_2$ branes are
unphysical, because the electric field on their worldvolume is supercritical.
By combining ${SL(2,\bR)}$ and SU(2), we exhibit a class of supersymmetric
AdS$_2\times S^2$ three-brane worldvolumes, and consider their possible
embeddings in the near-horizon region of stringy black holes. We point out the
intriguing difference between the induced and the effective geometries of these
D-branes, and speculate on its possible significance.

</DOC>
<DOC>
<DOCNO> 101021 </DOCNO>
Algebras without noetherian filtrations


  We provide examples of finitely generated noetherian PI algebras for which
there is no finite dimensional filtration with a noetherian associated graded
ring; thus we answer negatively a question raised by M. Lorenz.

</DOC>
<DOC>
<DOCNO> 100464 </DOCNO>
Large characteristic subgroups of surface groups not containing any


  We determine the largest (i.e. smallest index) characteristic subgroup of
surface groups not containing any simple loops.

</DOC>
<DOC>
<DOCNO> 39677 </DOCNO>
Neutrino physics


  In the present lectures the following topics are considered: general
properties of neutrinos, neutrino mass phenomenology (Dirac and Majorana
masses), neutrino masses in the simplest extensions of the standard model
(including the seesaw mechanism), neutrino oscillations in vacuum, neutrino
oscillations in matter (the MSW effect) in 2- and 3-flavour schemes,
implications of CP, T and CPT symmetries for neutrino oscillations, double beta
decay, solar neutrino oscillations and the solar neutrino problem, and
atmospheric neutrinos. We also give a short overview of the results of the
accelerator and reactor neutrino experiments and of future projects. Finally,
we discuss how the available experimental data on neutrino masses and lepton
mixing can be summarized in the phenomenologically allowed forms of the
neutrino mass matrix.

</DOC>
<DOC>
<DOCNO> 80932 </DOCNO>
Quenched charmonium spectrum on anisotropic lattices


  We present the results of quenched charmonium spectrum for S- and P-states,
obtained by a relativistic heavy quark method on anisotropic lattices.
Simulations are carried out using the standard plaquette gauge action and a
meanfield-improved clover quark action at $a_t^{-1} = 3$--6 GeV with the
renormalized anisotropy fixed to $\xi \equiv a_s/a_t =3$. We study the scaling
of our fine and hyperfine mass splittings, and compare with previous results.

</DOC>
<DOC>
<DOCNO> 84798 </DOCNO>
Relativistic Quantum Non-Locality


  The controversy between relativistic causality and quantum non-locality can
be resolved by establishing the general relativistic background of quantum
non-locality.

</DOC>
<DOC>
<DOCNO> 178758 </DOCNO>
Sigma Decay at Finite Temperature and Density


  Sigma decay and its relation with chiral phase transition are discussed at
finite temperature and density in the framework of the Nambu-Jona-Lasinio
model. The decay rate for the process sigma -> 2 pions to first order in a
1/N_c expansion is calculated as a function of temperature T and baryon density
n_b. In particular, only when the chiral phase transition happens around the
tricritical point, the sigma decay results in a non-thermal enhancement of
pions in the final state distributions in relativistic heavy ion collisions.

</DOC>
<DOC>
<DOCNO> 8682 </DOCNO>
Metallization of molecular hydrogen


  We study metallization of molecular hydrogen under pressure using exact
exchange (EXX) Kohn-Sham density-functional theory in order to avoid well-known
underestimates of band gaps associated with standard local-density or
generalized-gradient approximations. Compared with the standard methods, the
EXX approach leads to considerably (1 - 2 eV) higher gaps and significant
changes in the relative energies of different structures. Metallization is
predicted to occur at a density of >= 0.6 mol/cm^3 (corresponding to a pressure
of >= 400 GPa), consistent with all previous measurements.

</DOC>
<DOC>
<DOCNO> 116724 </DOCNO>
A Review Essay: "Lise Meitner and the Dawn of the Nuclear Age", by


  The recently published book, ``Lise Meitner and the Dawn of the Nuclear
Age'', by Patricia Rife (Boston: Birkh\"{a}user, 1999) is reviewed in an essay
for the lay audience. Meitner was a leading nuclear physicist at the time that
the nucleus was the most exciting frontier of science. To establish her career,
she had to overcome daunting prejudices against women in science and academia.
Being of Jewish origin in Germany in the 1930's, she narrowly escaped certain
disaster. Meitner was a crucial participant in the discovery of nuclear
fission, yet did not share in the Nobel Prize that her collaborator, Otto Hahn,
received in 1945. How these events came about, how they were intertwined with
contemporary history and how they fit into the evolution of Meitner's social
conscience and her abhorrence of war are some of the fascinating subjects
discussed in the book and reviewed in this essay.

</DOC>
<DOC>
<DOCNO> 122013 </DOCNO>
Semi-Analytical Models for Lensing by Dark Halos: I. Splitting Angles


  We use the semi-analytical approach to analyze gravitational lensing of
quasars by dark halos in various cold dark matter (CDM) cosmologies, in order
to determine the sensitivity of the prediction probabilities of images
separations to the input assumptions regarding halos and cosmologies. The mass
function of dark halos is assumed to be given by the Press-Schechter function.
The mass density profile of dark halos is alternatively taken to be the
singular isothermal sphere (SIS), the Navarro-Frenk-White (NFW) profile, or the
generalized NFW profile. The cosmologies include: the Einstein-de Sitter model
(SCDM), the open model (OCDM), and the flat \Lambda-model (LCDM). As expected,
we find that the lensing probability is extremely sensitive to the mass density
profile of dark halos, and somewhat less so to the mean mass density in the
universe, and the amplitude of primordial fluctuations. NFW halos are very much
less effective in producing multiple images than SIS halos. However, none of
these models can completely explain the current observations: the SIS models
predict too many large splitting lenses, while the NFW models predict too few
small splitting lenses. This indicates that there must be at least two
populations of halos in the universe. A combination of SIS and NFW halos can
reasonably reproduce the current observations if we choose the mass for the
transition from SIS to NFW to be ~ 10^{13} solar masses. Additionally, there is
a tendency for CDM models to have too much power on small scales, i.e. too much
mass concentration; and it appears that the cures proposed for other apparent
difficulties of CDM would help here as well, an example being the warm dark
matter (WDM) variant which is shown to produce large splitting lenses fewer
than the corresponding CDM model by one order of magnitude.

</DOC>
<DOC>
<DOCNO> 121718 </DOCNO>
Convective proton and He3 ingestion into helium burning: Nucleosynthesis


  A thermal pulse during the post-AGB phase of stellar evolution may lead to a
unique mode of light element nucleosynthesis. The stage is set by the ingestion
of the unprocessed envelope material into the hot He-flash convection zone
below. If the temperature is sufficiently large and the C12 abundance high
enough (e.g. T_8 > 0.8, X(C12) ~ 0.4 and X(H) ~ 1E-3) protons react faster with
C12 and form C13 than destroying Be7 The latter forms by alpha-capture of He3
after an initial reduction of the He3 abundance to about 3E-5 X(He4) by the ppI
reaction He3(He3,2p)He4 (for T_8 ~ 1). All He3 is burned within minutes to
weeks depending on the temperature. Be7 is now present at about the previously
mentioned level of He3. Its further fate is determined by the reactions
Be7(e-,nu)Li7 and the alpha-capture reactions of Be7 and Li7. These captures
lead to the production of Be11 which in turn is finally destroyed by
Be11(alpha,n)N14$. The details of this mechanism of light element production in
real stars is expected to be fairly dependent on the description of mixing.

</DOC>
<DOC>
<DOCNO> 70159 </DOCNO>
Resonant Slepton Production in Hadron-Hadron Collisions


  We consider the resonant production of sleptons via R-parity violation in
hadron-hadron collisions followed by supersymmetric gauge decays of the
sleptons. We look at decay modes which lead to the production of a like-sign
dilepton pair. The dominant production mechanism giving this signature is the
resonant production of a charged slepton followed by a decay to a charged
lepton and a neutralino which then decays via R-parity violation. The discovery
potential of this process at Run II of the Tevatron and the LHC is investigated
using the HERWIG Monte Carlo event generator. We include the backgrounds from
the MSSM. We conclude with a discussion of the possibility of extracting the
lightest neutralino and slepton masses.

</DOC>
<DOC>
<DOCNO> 7643 </DOCNO>
Appearance of spontaneous macroscopic magnetization at the


  We report the observation of a weak spontaneous magnetic field appearing at
the transition temperature of $\rm YBa_2Cu_3O_{7-\delta}$ into the
superconducting state. The effect is observed in 14 out of 15 epitaxial films
grown on different substrates and by two distinct techniques. The average
magnetic field sensed by the SQUID magnetometer is of the order of 10$^{-5}$ G.
The effect indicates a breaking of both parity and time reversal symmetries in
the superconductor. We consider two different interpretations: (i) The
condensate carries an intrinsic magnetic moment. At T=0, this moment is between
$\rm 10^{-2} \mu_B$ and $\rm 10^{-4} \mu_B$ per plaquette, depending whether
the width of the unscreened region near the edge of the film is the coherence
length or the penetration length. (ii) $\pi$ junctions which may exist near the
edges produce circulating supercurrents and magnetic flux. Constraints imposed
on these scenarios by temperature and geometry dependence of the data are
discussed.

</DOC>
<DOC>
<DOCNO> 102003 </DOCNO>
Considerations on New Functions in Number Theory


  In this paper a small survey is presented on eighteen new functions and four
new sequences, such as: Inferior/Superior f-Part, Fractional f-Part,
Complementary function with respect with another function, S-Multiplicative,
Primitive Function, Double Factorial Function, S-Prime and S-Coprime Functions,
Smallest Power Function.

</DOC>
<DOC>
<DOCNO> 100704 </DOCNO>
Summing inclusion maps between symmetric sequence spaces


  We prove a substantial extension of a well-known result due to Bennett and
Carl: The inclusion of a 2-concave symmetric Banach sequence space E into l_2
is (E,1)-summing, i.e. for every unconditionally summable sequence (x_n) in E
the scalar sequence (||x_n||_2) is contained in E. Various applications are
given, e.g. to the theory of eigenvalue distribution of compact operators and
approximation theory.

</DOC>
<DOC>
<DOCNO> 83335 </DOCNO>
Comparing two trainable grammatical relations finders


  Grammatical relationships (GRs) form an important level of natural language
processing, but different sets of GRs are useful for different purposes.
Therefore, one may often only have time to obtain a small training corpus with
the desired GR annotations. On such a small training corpus, we compare two
systems. They use different learning techniques, but we find that this
difference by itself only has a minor effect. A larger factor is that in
English, a different GR length measure appears better suited for finding simple
argument GRs than for finding modifier GRs. We also find that partitioning the
data may help memory-based learning.

</DOC>
<DOC>
<DOCNO> 10272 </DOCNO>
From avalanches to fluid flow: A continuous picture of grain dynamics


  Surface flows are excited by steadily adding spherical glass beads to the top
of a heap. To simultaneously characterize the fast single-grain dynamics and
the much slower collective intermittency of the flow, we extend
photon-correlation spectroscopy via fourth-order temporal correlations in the
scattered light intensity. We find that microscopic grain dynamics during an
avalanche are similar to those in the continuous flow just above the
transition. We also find that there is a minimum jamming time, even arbitrarily
close to the transition.

</DOC>
<DOC>
<DOCNO> 117639 </DOCNO>
The spectra and energies of classical double radio lobes


  We compare two temporal properties of classical double radio sources: i)
radiative lifetimes of synchrotron-emitting particles and ii) dynamical source
ages. We discuss how these can be quite discrepant from one another, rendering
use of the traditional spectral ageing method inappropriate: we contend that
spectral ages give meaningful estimates of dynamical ages only when these ages
are << 10^7 years. In juxtaposing the fleeting radiative lifetimes with source
ages which are significantly longer, a refinement of the paradigm for radio
source evolution is required. The changing spectra along lobes are explained,
not predominantly by synchrotron ageing but, by gentle gradients in a magnetic
field mediated by a low-gamma matrix which illuminates an energy-distribution
of particles, controlled largely by classical synchrotron loss in the high
magnetic field of the hotspot. The energy in the particles is an order of
magnitude higher than that inferred from the minimum-energy estimate, implying
that the jet-power is of the same order as the accretion luminosity produced by
the quasar central engine. This refined paradigm points to a resolution of the
findings of Rudnick et al (1994) and Katz-Stone & Rudnick (1994) that both the
Jaffe-Perola and Kardashev-Pacholczyk model spectra are invariably poor
descriptions of the curved spectral shape of lobe emission, and indeed that for
Cygnus A all regions of the lobes are characterised by a `universal spectrum'.
[abridged]

</DOC>
<DOC>
<DOCNO> 120026 </DOCNO>
Microlensing in M31 - The MEGA Survey's Prospects and Initial Results


  January 2000 completes the first season of intensive, wide-field observations
of microlensing and stellar variability in M31 by MEGA (Microlensing
Exploration of the Galaxy and Andromeda) at the Isaac Newton 2.5m Telescope,
the KPNO 4m, and the 1.3m and 2.5m telescopes of MDM Observatory. In
preliminary analysis, we detect ~50000 variable objects, including some
consistent with microlensing events. We present the level of sensitivity to be
reached in our planned three-year program to test for the presence of a
significant halo microlensing population in M31, as well as its spatial
distribution and mass-function. We also discuss our application of image
subtraction to these wide fields and HST WFPC2 Snapshot followup observations
to confirm candidates identified from previous years' surveys.
   We present intermediate results from our smaller-field survey, on the MDM
1.3m and Vatican Advanced Technology 1.8m Telescope, from 1994-1998, wherein we
have discovered 8 additional probable microlensing events, over about one-half
the time base of the project, in addition to confirming three of our original 6
microlensing candidates from 1995.

</DOC>
<DOC>
<DOCNO> 7684 </DOCNO>
Asymptotic Behavior of Thermal Non-Equilibrium Steady States for a


  We consider a model of heat conduction which consists of a finite nonlinear
chain coupled to two heat reservoirs at different temperatures. We study the
low temperature asymptotic behavior of the invariant measure. We show that, in
this limit, the invariant measure is characterized by a variational principle.
We relate the heat flow to the variational principle. The main technical
ingredient is an extension of Freidlin-Wentzell theory to a class of degenerate
diffusions.

</DOC>
<DOC>
<DOCNO> 13305 </DOCNO>
A repulsive trap for two electrons in a magnetic field


  We study numerically and analytically the dynamics of two classical electrons
with Coulomb interaction in a two dimensional antidot superlattice potential in
the presence of crossed electric and magnetic fields. It is found that near one
antidot the electron pair can be trapped for a long time and the escape rate
from such a trap is proportional to the square of a weak electric field. This
is qualitatively different from the case of noninteracting electrons which are
trapped forever by the antidot. For the pair propagation in the antidot
superlattice we found a broad parameter regime for which the pair is stable and
where two repulsive electrons propagate together on an enormously large
distance.

</DOC>
<DOC>
<DOCNO> 119351 </DOCNO>
Type Ia Supernova Explosion Models: Homogeneity versus Diversity


  Type Ia supernovae (SN Ia) are generally believed to be the result of the
thermonuclear disruption of Chandrasekhar-mass carbon-oxygen white dwarfs,
mainly because such thermonuclear explosions can account for the right amount
of Ni-56, which is needed to explain the light curves and the late-time
spectra, and the abundances of intermediate-mass nuclei which dominate the
spectra near maximum light. Because of their enormous brightness and apparent
homogeneity SN Ia have become an important tool to measure cosmological
parameters. In this article the present understanding of the physics of
thermonuclear explosions is reviewed. In particular, we focus our attention on
subsonic (``deflagration'') fronts, i.e. we investigate fronts propagating by
heat diffusion and convection rather than by compression. Models based upon
this mode of nuclear burning have been applied very successfully to the SN Ia
problem, and are able to reproduce many of their observed features remarkably
well. However, the models also indicate that SN Ia may differ considerably from
each other, which is of importance if they are to be used as standard candles.

</DOC>
<DOC>
<DOCNO> 101022 </DOCNO>
Explicit formulas for the multivariate resultant


  We present formulas for the homogenous multivariate resultant as a quotient
of two determinants. They extend classical Macaulay formulas, and involve
matrices of considerably smaller size, whose non zero entries include
coefficients of the given polynomials and coefficients of their Bezoutian.
These formulas can also be viewed as an explicit computation of the morphisms
and the determinant of a resultant complex.

</DOC>
<DOC>
<DOCNO> 11892 </DOCNO>
Single electron magneto-conductivity of a nondegenerate 2D electron


  We study transport properties of a non-degenerate two-dimensional system of
non-interacting electrons in the presence of a quantizing magnetic field and a
short-range disorder potential. We show that the low-frequency
magnetoconductivity displays a strongly asymmetric peak at a nonzero frequency.
The shape of the peak is restored from the calculated 14 spectral moments, the
asymptotic form of its high-frequency tail, and the scaling behavior of the
conductivity for omega -> 0. We also calculate 10 spectral moments of the
cyclotron resonance absorption peak and restore the corresponding
(non-singular) frequency dependence using the continuous fraction expansion.
Both expansions converge rapidly with increasing number of included moments,
and give numerically accurate results throughout the region of interest. We
discuss the possibility of experimental observation of the predicted effects
for electrons on helium.

</DOC>
<DOC>
<DOCNO> 101245 </DOCNO>
Bures Geometry of the Three-Level Quantum Systems. I


  We compute, using a formula of Dittmann, the Bures metric tensor (g) for the
eight-dimensional convex set of three-level quantum systems, employing a
newly-developed Euler angle-based parameterization of the 3 x 3 density
matrices. Most of the individual metric elements (g_{ij}) are found to be
expressible in relatively compact form, many of them in fact being exactly
zero.

</DOC>
<DOC>
<DOCNO> 101499 </DOCNO>
Hausdorff Convergence and Universal Covers


  We prove that if $Y$ is the Gromov-Hausdorff limit of a sequence of compact
manifolds, $M^n_i$, with a uniform lower bound on Ricci curvature and a uniform
upper bound on diameter, then $Y$ has a universal cover. We then show that, for
$i$ sufficiently large, the fundamental group of $M_i$ has a surjective
homeomorphism onto the group of deck transforms of $Y$. Finally, in the
non-collapsed case where the $M_i$ have an additional uniform lower bound on
volume, we prove that the kernels of these surjective maps are finite with a
uniform bound on their cardinality. A number of theorems are also proven
concerning the limits of covering spaces and their deck transforms when the
$M_i$ are only assumed to be compact length spaces with a uniform upper bound
on diameter.

</DOC>
<DOC>
<DOCNO> 84543 </DOCNO>
Towards the classification of static vacuum spacetimes with negative


  We present a systematic study of static solutions of the vacuum Einstein
equations with negative cosmological constant which asymptotically approach the
generalized Kottler (``Schwarzschild--anti-de Sitter'') solution, within
(mainly) a conformal framework. We show connectedness of conformal infinity for
appropriately regular such space-times. We give an explicit expression for the
Hamiltonian mass of the (not necessarily static) metrics within the class
considered; in the static case we show that they have a finite and well defined
Hawking mass. We prove inequalities relating the mass and the horizon area of
the (static) metrics considered to those of appropriate reference generalized
Kottler metrics. Those inequalities yield an inequality which is opposite to
the conjectured generalized Penrose inequality. They can thus be used to prove
a uniqueness theorem for the generalized Kottler black holes if the generalized
Penrose inequality can be established.

</DOC>
<DOC>
<DOCNO> 11586 </DOCNO>
Melting and transverse depinning of driven vortex lattices in the


  We study the non-equilibrium dynamical regimes of a moving vortex lattice in
the periodic pinning of a Josephson junction array (JJA) for {\it finite
temperatures} in the case of a fractional or submatching field. We obtain a
phase diagram for the current driven JJA as a function of the driving current I
and temperature T. We find that when the vortex lattice is driven by a current,
the depinning transition at $T_p(I)$ and the melting transition at $T_M(I)$
become separated even for a field for which they coincide in equilibrium. We
also distinguish between the depinning of the vortex lattice in the direction
of the current drive, and the {\it transverse depinning} in the direction
perpendicular to the drive. The transverse depinning corresponds to the onset
of transverse resistance in a moving vortex lattice at a given temperature
$T_{tr}$. For driving currents above the critical current we find that the
moving vortex lattice has first a transverse depinning transition at low T, and
later a melting transition at a higher temperature, $T_{M}>T_{tr}$.

</DOC>
<DOC>
<DOCNO> 100502 </DOCNO>
Reduction of covers and Hurwitz spaces


  In this paper we study the reduction of Galois covers of curves, from
characteristic 0 to characteristic p. The starting point is a is a recent
result of Raynaud which gives a criterion for good reduction for covers of the
projective line branch at 3 points. Under some condition on the Galois group,
we extend this criterion to the case of 4 branch points. Moreover, we describe
the reduction of the Hurwitz space of such covers and compute the number of
covers with good reduction.

</DOC>
<DOC>
<DOCNO> 101370 </DOCNO>
Gap Probabilities for Edge Intervals in Finite Gaussian and Jacobi


  The probabilities for gaps in the eigenvalue spectrum of the finite dimension
$ N \times N $ random matrix Hermite and Jacobi unitary ensembles on some
single and disconnected double intervals are found. These are cases where a
reflection symmetry exists and the probability factors into two other related
probabilities, defined on single intervals. Our investigation uses the system
of partial differential equations arising from the Fredholm determinant
expression for the gap probability and the differential-recurrence equations
satisfied by Hermite and Jacobi orthogonal polynomials. In our study we find
second and third order nonlinear ordinary differential equations defining the
probabilities in the general $N$ case. For N=1 and N=2 the probabilities and
thus the solution of the equations are given explicitly. An asymptotic
expansion for large gap size is obtained from the equation in the Hermite case,
and also studied is the scaling at the edge of the Hermite spectrum as $ N \to
\infty $, and the Jacobi to Hermite limit; these last two studies make
correspondence to other cases reported here or known previously. Moreover, the
differential equation arising in the Hermite ensemble is solved in terms of an
explicit rational function of a {Painlev\'e-V} transcendent and its derivative,
and an analogous solution is provided in the two Jacobi cases but this time
involving a {Painlev\'e-VI} transcendent.

</DOC>
<DOC>
<DOCNO> 119346 </DOCNO>
A New Association of Post-T Tauri Stars Near The Sun


  Observing ROSAT sources in 20 x 25 deg centered at the high latitude active
star ER Eri, we found evidences for a new young nearby association (~30Myr
at~60pc), the Horologium Association (HorA), formed by at least 10 probable and
6 possible members, some being Post-T Tauri stars. We examine several
requirements that characterize a young association and they, together, create a
strong evidence for the reality of the HorA. In fact, the Li line intensities
are between those of the oldest classical T Tauri stars and the ones of the
Local Association stars. The space velocities of the HorA relative to the Sun,
U= -9.5+/-1.0, V = -20.9 +/- 1.1, W = -2.1 +/- 1.9, are not far from those of
the Local Association. We suggest that some hotter and non-X-ray active stars,
with similar space velocities, could be massive members of the HorA, among
them, the nearby Be star Achernar. The maximum of the mass distribution
function of the HorA is around 0.8 solar masses. At its distance, the projected
size of the HorA, ~50 pc, would be larger than our surveyed area and many other
members could have been missed. We also observed 3 control regions, two at
northern and southern galactic latitudes and a third one in the known TW Hya
Association (TWA), and the properties and distribution of their young stars
strengthen the reality of the HorA. Contrary to the TWA, the only known
binaries in the HorA are 2 very wide systems. The HorA is much more isolated
from clouds and older than the TWA and could give some clues about the lifetime
of the disks around T Tauri stars. Actually, none of the proposed members is an
IRAS source indicating an advanced stage of the evolution of their accreting
disks. ER Eri itself was found to be a RS CVn-like system.

</DOC>
<DOC>
<DOCNO> 7963 </DOCNO>
The sign problem in Monte Carlo simulations of frustrated quantum spin


  We discuss the sign problem arising in Monte Carlo simulations of frustrated
quantum spin systems. We show that for a class of ``semi-frustrated'' systems
(Heisenberg models with ferromagnetic couplings $J_z(r) < 0$ along the $z$-axis
and antiferromagnetic couplings $J_{xy}(r)=-J_z(r)$ in the $xy$-plane, for
arbitrary distances $r$) the sign problem present for algorithms operating in
the $z$-basis can be solved within a recent ``operator-loop'' formulation of
the stochastic series expansion method (a cluster algorithm for sampling the
diagonal matrix elements of the power series expansion of ${\rm exp}(-\beta H)$
to all orders). The solution relies on identification of operator-loops which
change the configuration sign when updated (``merons'') and is similar to the
meron-cluster algorithm recently proposed by Chandrasekharan and Wiese for
solving the sign problem for a class of fermion models (Phys. Rev. Lett. {\bf
83}, 3116 (1999)). Some important expectation values, e.g., the internal
energy, can be evaluated in the subspace with no merons, where the weight
function is positive definite. Calculations of other expectation values require
sampling of configurations with only a small number of merons (typically zero
or two), with an accompanying sign problem which is not serious. We also
discuss problems which arise in applying the meron concept to more general
quantum spin models with frustrated interactions.

</DOC>
<DOC>
<DOCNO> 13864 </DOCNO>
Dynamic critical properties of the vortex-glass transition derived from


  We present resistivity data on a high-quality
La$_{2-x}$Sr$_{x}$CuO$_{4-\delta}$ film measured in a magnetic field of 1 T
applied at an angle $\delta$ to the c axis. Using these data, the influence of
the orientation of the magnetic field and the effective mass anisotropy on the
vortex-glass transition can be studied. The variation of $\delta$ for a fixed
magnitude of the magnetic field allows us to investigate the critical
properties of interest, including the 2D-to-3D crossover and the 3D vortex
glass-to-fluid transition, as the temperature is decreased. The data are well
described by the scaling theory for the d.c. resistivity of an anisotropic
superconductor in a magnetic field applied at an angle $\delta$ to the c axis.
This scaling includes the critical properties close to and at the vortex-glass
transition. The main results include (i) evidence of a Kosterlitz-Thouless
transition in zero field, and (ii) a 2D-to-3D crossover at H=1 T as the
temperature is decreased below the zero-field transition temperature, leading
to the vortex fluid-to-vortex glass transition in D = 3 characterized by the
dynamic critical exponent $z\approx 5.7$.

</DOC>
<DOC>
<DOCNO> 72215 </DOCNO>
Beyond the Standard Model (In Search of Supersymmetry)


  The present lectures contain an introduction to low energy supersymmetry, a
new symmetry that relates bosons and fermions, in particle physics. The
Standard Model of fundamental interactions is briefly reviewed, and the
motivation to introduce supersymmetry is discussed. The main notions of
supersymmetry are introduced. The supersymmetric extension of the Standard
Model - the Minimal Supersymmetric Standard Model - is considered in more
detail. Phenomenological features of the MSSM as well as possible experimental
signatures of SUSY are described. An intriguing situation with the
supersymmetric Higgs boson is discussed.

</DOC>
<DOC>
<DOCNO> 68070 </DOCNO>
SUSY Higgs at the LHC: Effects of light charginos and neutralinos


  In view of the latest LEP data we consider the effects of charginos and
neutralinos on the two-photon and bbbar signatures of the Higgs at the LHC.
Assuming the usual GUT inspired relation between M_1 and M_2 we show that there
are only small regions with moderate tanbeta and large stop mixings that may be
dangerous. Pathological models not excluded by LEP which have degeneracy
between the sneutrino and the chargino are however a real danger because of
large branching fraction of the Higgs into invisibles. We have also studied
models where the gaugino masses are not unified at the GUT scale. We take
M_1=M_2/10 as an example where large reductions in the signal at the LHC can
occur. However we argue that such models with a very light neutralino LSP may
give a too large relic density unless the sleptons are light. We then combine
this cosmological constraint with neutralino production with light sfermions to
further reduce the parameter space that precludes observability of the Higgs at
the LHC. We still find regions of parameter space where the drops in the usual
Higgs signals at the LHC can be drastic. Nonetheless, in such scenarios where
Higgs may escape detection we show that one should be able to produce all
charginos and neutralinos. Although the heavier of these could cascade into the
Higgs, the rates are not too high and the Higgs may not always be recovered
this way.

</DOC>
<DOC>
<DOCNO> 85533 </DOCNO>
Static Anisotropic Solutions to Einstein Equations with a Nonlocal


  We present a general method to obtain static anisotropic spherically
symmetric solutions, satisfying a nonlocal equation of state, from known
density profiles. This equation of state describes, at a given point, the
components of the corresponding energy-momentum tensor not only as a function
at that point, but as a functional throughout the enclosed configuration. In
order to establish the physical aceptability of the proposed static family of
solutions satisfying nonlocal equation of state,\textit{}we study the
consequences imposed by the junction and energy conditions for anisotropic
fluids in bounded matter distribution. It is shown that a general relativistic
spherically symmetric bounded distributions of matter, at least for certain
regions, could satisfy a nonlocal equation of state.

</DOC>
<DOC>
<DOCNO> 120815 </DOCNO>
Theoretical Models of Photodissociation Fronts


  Observations of H2 line emission have revealed higher-than-expected gas
temperatures in a number of photodissociation fronts. We discuss the heating
and cooling processes in photodissociation regions. Observations of NGC 2023
are compared to a theoretical model in which there is substantial gas at
temperatures T = 500-1000K heated by photoelectric emission and collisional
deexcitation of H2. In general the model successfully reproduces the observed
H2 line emission from a wide range of energy levels. The observed [SiII]34.8um
emission appears to indicate substantial depletion of Si in NGC 2023.

</DOC>
<DOC>
<DOCNO> 118486 </DOCNO>
A Search for Stars of Very Low Metal Abundance. IV. uvbyCa Observations


  CCD photometry on the uvbyCa system has been obtained for 521 candidate
metal-poor stars from the northern hemisphere HK survey of Beers and
colleagues. Reddening corrections, classifications of stars by luminosity
class, and the derivation of metal abundances based on Stromgren indices m1 and
hk are described and presented, along with preliminary spectroscopic estimates
of abundance. A number of extremely metal-poor stars with [Fe/H] less than or
equal to -2.50 are identified.

</DOC>
<DOC>
<DOCNO> 119173 </DOCNO>
The Globular Cluster System in the Inner Region of the Giant Elliptical


  We present a study of globular clusters in the inner region of the giant
elliptical galaxy NGC 4472, based on the HST WFPC2 archive data. We have found
about 1560 globular cluster candidates at the galactocentric radius r < 4
arcmin. V-(V-I) diagram of these objects shows a dominant vertical structure
which consists obviously of two components: blue globular clusters (BGCs) and
red globular clusters (RGCs). The luminosity function of the globular clusters
is derived to have a peak at V(max)=23.50+/-0.16 from Gaussian fitting. The
distance to NGC 4472 is estimated to be d=14.7+/-1.3 Mpc.The peak luminosity
for the RGCs is similar to that for the BGCs, which indicates that the RGCs may
be several Gyrs younger than the BGCs. The mean luminosity of the bright BGCs
decreases by 0.2 mag with increasing galactocentric radius over the range of 9
arcmin, while that of the RGCs does not. The observed color distribution of
these globular clusters is distinctively bimodal with peaks at (V-I) = 0.98 and
1.23. The mean observed color of all the globular clusters with V < 23.9 mag is
derived to be (V-I)=1.11. These colors are exactly the same as those for the
globular clusters in M87. It is found that the relative number of the BGCs to
the RGCs is increasing with the increasing galactocentric radius. Surface
number density profiles of both the BGCs and RGCs get flat in the central
region, and the core radii of the globular cluster systems are measured to be
r_c = 1.9 arcmin for the BGCs, r_c = 1.2 arcmin for the RGCs, and r_c = 1.3
arcmin for the total sample, which are much larger than the stellar core of the
galaxy. In general the properties of the globular clusters in the inner region
of NGC 4472 are consistent with those of the globular clusters in the outer
region of NGC 4472.

</DOC>
<DOC>
<DOCNO> 12335 </DOCNO>
Two electrons in a two dimensional random potential: exchange,


  The problem of two electrons in a two-dimensional random potential is
addressed numerically. Specifically, the role of the Coulomb interaction
between electrons on localization is investigated by writing the Hamiltonian on
a localized basis and diagonalizing it exactly. The result of that procedure is
discussed in terms of level statistics, the expectation value of the
electron-electron separation, and a configuration-space inverse participation
number. We argue that, in the interacting problem, a
localization-delocalization crossover in real space does not correspond exactly
to a Poisson-Wigner crossover in level statistics.

</DOC>
<DOC>
<DOCNO> 119050 </DOCNO>
Status Report of Project GRAND: An Extensive Air Shower Array of


  Project GRAND is an extensive air shower array utilizing position sensitive
detectors of proportional wire chambers. The 64 detectors deployed in a field
100 m x 100 m are located at 86.2 deg W and 41.7 deg N, at 220 m above sea
level. The project was completed about two years ago and has been taking data,
simultaneously on two triggers: 1) multiple-hit coincidence triggers which
collect data on extensive air showers, and 2) 200 Hz triggers which collect the
single tracks stored in each station during the last 5 msec.

</DOC>
<DOC>
<DOCNO> 117235 </DOCNO>
Characterisation of the probabilistic travelling salesman problem


  A new stochastic optimisation technique has enabled us to explore the
probabilistic travelling salesman problem (PTSP) with large numbers of cities
(hitherto unobtainable). In this problem, the salesman must chose the
`a-priori' order in which to visit the cities, before learning that certain
cities do not need to be visited, and can be pruned from the tour. The
objective is to minimise the expected length of the pruned tour. We find the
mean length of the pruned tour, for n much less than 1, follows
E(L_{pruned})=\sqrt{np}(0.872-0.105p)f(np) where n is the number of cities, p
is the probability of a city needing a visit, and f(np) tends to 1 as np tends
to infinity. The mean length of the a-priori tour is found to be
E(L_{a-priori}) =\sqrt{(n/p)}\beta (p) where \beta (p)=1/(1.25 - 0.82 ln(p)) is
measured for 0.05 < p < 0.6. Scaling arguments and indirect measurements
suggest that \beta (p) tends towards a constant for p < 0.03.

</DOC>
<DOC>
<DOCNO> 10927 </DOCNO>
Rare-event induced binding transition of heteropolymers


  Sequence heterogeneity broadens the binding transition of a polymer onto a
linear or planar substrate. This effect is analyzed in a real-space
renormalization group scheme designed to capture the statistics of rare events.
In the strongly disordered regime, binding initiates at an exponentially rare
set of ``good contacts''. Renormalization of the contact potential yields a
Kosterlitz-Thouless type transition in any dimension. This and other
predictions are confirmed by extensive numerical simulations of a directed
polymer interacting with a columnar defect.

</DOC>
<DOC>
<DOCNO> 151159 </DOCNO>
Exact Cosmological Solution and Modulus Stabilization in the


  We provide the exact time-dependent cosmological solutions in the
Randall-Sundrum (RS) setup with bulk matter, which may be smoothly connected to
the static RS metric. In the static limit of the extra dimension, the solutions
are reduced to the standard Friedmann equations. In view of our solutions, we
also propose an explanation for how the extra dimension is stabilized in spite
of a flat modulus potential at the classical level.

</DOC>
<DOC>
<DOCNO> 70443 </DOCNO>
Effects of Instantons on the YN Interaction


  We investigate the symmetric and anti-symmetric spin-orbit forces (SLS and
ALS) of the effective $\Lambda$N interaction derived from a quark cluster model
with the instanton-induced interaction (\III), which can reproduce the observed
YN cross sections as well as the observed NN scattering data.
  It is found that coupling to the $\Sigma$N channel enhances $\Lambda$N ALS,
and therefore that the cancellation between SLS and ALS in the $\Lambda$N
channel becomes more complete. This may be one of the major reasons why the
single-particle spin-orbit force of $\Lambda$ in nuclei is weak.

</DOC>
<DOC>
<DOCNO> 84090 </DOCNO>
4d neutral dilatonic black holes and (4+p) dimensional nondilatonic


  It is shown that, in contrast to the case of extreme 4d dilatonic black
holes, 4d neutral dilatonic black holes with horizon singularities can not be
interpreted as nonsingular nondilatonic black p-branes in (4+p) dimensions,
regardless of the number of extra dimensions p. That is, extra dimensions do
not remove naked singularities of 4d neutral dilatonic black holes.

</DOC>
<DOC>
<DOCNO> 10957 </DOCNO>
Spinless impurities and Kondo-like behavior in strongly correlated


  We investigate magnetic properties induced by a spinless impurity in strongly
correlated electron systems, i.e. the Hubbard model in the spatial dimension
$D=1,2,$ and 3. For the 1D system exploiting the Bethe ansatz exact solution we
find that the spin susceptibility and the local density of states in the
vicinity of a spinless impurity show divergent behaviors. The results imply
that the induced local moment is not completely quenched at any finite
temperatures. On the other hand, the spin lattice relaxation rate obtained by
bosonization and boundary conformal field theory satisfies a relation analogous
to the Korringa law, $1/T_1T \sim \chi^2$. In the 2D and 3D systems, the
analysis based upon the antiferromagnetically correlated Fermi liquid theory
reveals that the antiferromagnetic spin fluctuation developed in the bulk is
much suppressed in the vicinity of a spinless impurity, and thus magnetic
properties are governed by the induced local moment, which leads to the
Korringa law of $1/T_1$.

</DOC>
<DOC>
<DOCNO> 10976 </DOCNO>
Inertial waves in a rotating spherical shell: attractors and asymptotic


  We investigate the asymptotic properties of inertial modes confined in a
spherical shell when viscosity tends to zero. We first consider the mapping
made by the characteristics of the hyperbolic equation (Poincar\'e's equation)
satisfied by inviscid solutions. Characteristics are straight lines in a
meridional section of the shell, and the mapping shows that, generically, these
lines converge towards a periodic orbit which acts like an attractor.
 We then examine the relation between this characteristic path and
eigensolutions of the inviscid problem and show that in a purely
two-dimensional problem, convergence towards an attractor means that the
associated velocity field is not square-integrable. We give arguments which
generalize this result to three dimensions. We then consider the viscous
problem and show how viscosity transforms singularities into internal shear
layers which in general betray an attractor expected at the eigenfrequency of
the mode. We find that there are nested layers, the thinnest and most internal
layer scaling with $E^{1/3}$-scale, $E$ being the Ekman number. Using an
inertial wave packet traveling around an attractor, we give a lower bound on
the thickness of shear layers and show how eigenfrequencies can be computed in
principle. Finally, we show that as viscosity decreases, eigenfrequencies tend
towards a set of values which is not dense in $[0,2\Omega]$, contrary to the
case of the full sphere ($\Omega$ is the angular velocity of the system).
Hence, our geometrical approach opens the possibility of describing the
eigenmodes and eigenvalues for astrophysical/geophysical Ekman numbers
($10^{-10}-10^{-20}$), which are out of reach numerically, and this for a wide
class of containers.

</DOC>
<DOC>
<DOCNO> 122948 </DOCNO>
Theoretical considerations on colliding clumped winds


  First attempts are made to derive astrophysical implications of the collision
of clumped stellar winds from order of magnitude estimates and preliminary
numerical simulations. Compared to colliding smooth winds, we find that the
most significant differences occur in widely separated systems like WR 140.
Clumped winds de-stabilize the wind-wind interaction zone of such systems.
Highly compressed, cold knots of WR-wind material can form. Hydrogen rich
material is likely to be mixed into these knots by the excited turbulence. Such
knots, therefore, are good candidates to form dust. We briefly discuss to what
degree our results can be applied to other systems and look at different
possibilities for the origin and nature of the inhomogeneities in hot star
winds.

</DOC>
<DOC>
<DOCNO> 69378 </DOCNO>
Quantum Field Theory of the Laser Acceleration


  After the historical background concerning the pressure of light, we derive
the quantum field theory force of the laser radiation acting on electron.
Numerically, we determine the velocity of an electron accelerated by laser
beam, after acceleration time $\Delta t = 1 {\rm s}$.

</DOC>
<DOC>
<DOCNO> 71942 </DOCNO>
Stochastic Theory of Relativistic Particles Moving in a Quantum Field:


  We treat a relativistically moving particle interacting with a quantum field
from an open system viewpoint of quantum field theory by the method of
influence functionals or closed-time-path coarse-grained effective actions. The
particle trajectory is not prescribed but is determined by the backreaction of
the quantum field in a self-consistent way. Coarse-graining the quantum field
imparts stochastic behavior in the particle trajectory. The formalism is set up
here as a precursor to a first principles derivation of the
Abraham-Lorentz-Dirac (ALD) equation from quantum field theory as the correct
equation of motion valid in the semiclassical limit. This approach also
discerns classical radiation reaction from quantum dissipation in the motion of
a charged particle; only the latter is related to vacuum fluctuations in the
quantum field by a fluctuation-dissipation relation, which we show to exist for
nonequilibrim processes under this type of nonlinear coupling. This formalism
leads naturally to a set of Langevin equations associated with a generalized
ALD equation. These multiparticle stochastic differential equations feature
local dissipation (for massless quantum fields), nonlocal particle-particle
interactions, multiplicative noise, and nonlocal particle-particle
correlations, interrelated in ways characteristic of nonlinear theories,
through generalized fluctuation-dissipation relations.

</DOC>
<DOC>
<DOCNO> 10961 </DOCNO>
Coulomb blockade of tunnelling through compressible rings formed around


  We consider single-electron tunnelling through antidot states using a
Coulomb-blockade model, and give an explanation for h/2e Aharonov-Bohm
oscillations, which are observed experimentally when the two spins of the
lowest Landau level form bound states. We show that the edge channels may
contain compressible regions, and using simple electrostatics, that the
resonance through the outer spin states should occur twice per h/e period. An
antidot may be a powerful tool for investigating quantum Hall edge states in
general, and the interplay of spin and charging effects that occurs in quantum
dots.

</DOC>
<DOC>
<DOCNO> 151904 </DOCNO>
Reduced Models and Noncommutative Gauge Theories


  This is a short review of the relation between the Reduced Models and
Noncommutative Yang-Mills Theories (NCYM) based on the work done in
collaboration with J. Ambjorn, J. Nishimura and R. Szabo. Contents: 1.Twisted
Eguchi-Kawai model (TEK), 2.Mapping onto NCYM, 3.Morita equivalence,
4.Fundamental matter, 5.Wilson loops in NCYM, 6.D-brane interpretation. Talk
given at the 11th International Seminar "Quarks'2000", Pushkin, Russia, May
13-21, 2000 and the E.S.Fradkin Memorial Conference, Moscow, June 5-10, 2000.

</DOC>
<DOC>
<DOCNO> 102906 </DOCNO>
Tilings of quadriculated annuli


  Tilings of a quadriculated annulus A are counted according to volume (in the
formal variable q) and flux (in p). We consider algebraic properties of the
resulting generating function \Phi_A(p,q). For q = -1, the non-zero roots in p
must be roots of unity and for q > 0, real negative.

</DOC>
<DOC>
<DOCNO> 121707 </DOCNO>
Microscopic calculations for solar nuclear reactions


  We have studied the 4He(3He,gamma)7Be, 3He(3He,2p)4He, and 7Be(p,gamma)8B
reactions of the solar p-p chain, using microscopic cluster models. Among other
results, we showed that the 6Li+p channel has a nontrivial effect on the
7Be-producing reaction, that the existence of a resonance in 6Be close to the
3He+3He threshold is rather unlikely, and that the correlations between some
properties of 7Be/8B and the low-energy cross section of 7Be(p,gamma)8B might
help one to constrain the value of the S_17(0) astrophysical S-factor.

</DOC>
<DOC>
<DOCNO> 12248 </DOCNO>
Simulating Dynamical Features of Escape Panic


  One of the most disastrous forms of collective human behaviour is the kind of
crowd stampede induced by panic, often leading to fatalities as people are
crushed or trampled. Sometimes this behaviour is triggered in life-threatening
situations such as fires in crowded buildings; at other times, stampedes can
arise from the rush for seats or seemingly without causes. Tragic examples
within recent months include the panics in Harare, Zimbabwe, and at the
Roskilde rock concert in Denmark. Although engineers are finding ways to
alleviate the scale of such disasters, their frequency seems to be increasing
with the number and size of mass events. Yet, systematic studies of panic
behaviour, and quantitative theories capable of predicting such crowd dynamics,
are rare. Here we show that simulations based on a model of pedestrian
behaviour can provide valuable insights into the mechanisms of and
preconditions for panic and jamming by incoordination. Our results suggest
practical ways of minimising the harmful consequences of such events and the
existence of an optimal escape strategy, corresponding to a suitable mixture of
individualistic and collective behaviour.

</DOC>
<DOC>
<DOCNO> 80903 </DOCNO>
Effects of non-perturbatively improved dynamical fermions in UKQCD


  We present results for QCD with 2 degenerate flavours of quark using a
non-perturbatively improved action on a lattice volume of $16^3\times32$ where
the bare gauge coupling and bare dynamical quark mass have been chosen to
maintain a fixed physical lattice spacing and volume (1.71 fm). By comparing
measurements from these matched ensembles, including quenched ones, we find
evidence of dynamical quark effects on the short distance static potential, the
scalar glueball mass and the topological susceptibility. There is little
evidence of effects on the light hadron spectrum over the range of quark masses
studied ($m_{\pi}/m_{\rho}\geq 0.60$).

</DOC>
<DOC>
<DOCNO> 8979 </DOCNO>
Sequential fragmentation: The origin of columnar quasi-hexagonal


  We present a model that explains the origin and predicts the statistical
properties of columnar quasi-hexagonal crack patterns, as observed in the
columnar jointing of basaltic lava flows. Irregular fractures appear at the
surface of the material, induced by temperature gradients during cooling. At
later times fractures penetrate into the material, and tend to form polygonal
patterns. We show that this ordering can be described as a tendency to minimize
an energy functional. Atomistic simulations confirm this interpretation.
Numerical simulations based on a phenomenological implementation of this
principle generate patterns that have remarkably good statistical agreement
with real ones.

</DOC>
<DOC>
<DOCNO> 99376 </DOCNO>
Abel ODEs: Equivalence and Integrable Classes


  A classification, according to invariant theory, of non-constant invariant
Abel ODEs known as solvable and found in the literature is presented. A set of
new integrable classes depending on one or no parameters, derived from the
analysis of the works by Abel, Liouville and Appell, is also shown. Computer
algebra routines were developed to solve ODEs members of these classes by
solving their related equivalence problem. The resulting library permits a
systematic solving of Abel type ODEs in the Maple symbolic computing
environment.

</DOC>
<DOC>
<DOCNO> 99381 </DOCNO>
Random almost holomorphic sections of ample line bundles on symplectic


  The spaces $H^0(M, L^N)$ of holomorphic sections of the powers of an ample
line bundle $L$ over a compact K\"ahler manifold $(M,\omega)$ have been
generalized by Boutet de Monvel and Guillemin to spaces $H^0_J(M, L^N)$ of
`almost holomorphic sections' of ample line bundles over an almost complex
symplectic manifold $(M, J, \omega)$. We consider the unit spheres $SH^0_J(M,
L^N)$ in the spaces $H^0_J(M, L^N)$, which we equip with natural inner
products. Our purpose is to show that, in a probabilistic sense, almost
holomorphic sections behave like holomorphic sections as $N \to \infty$. Our
first main result is that almost all sequences of sections $s_N \in SH^0_J(M,
L^N)$ are `asymptotically holomorphic' in the Donaldson-Auroux sense that
$||s_N||_{\infty}/||s_N||_{2} = O(\sqrt{\log N})$, $||\bar{\partial}
s_N||_{\infty}/||s_N||_{2} = O(\sqrt{\log N})$ and $||\partial
s_N||_{\infty}/||s_N||_{2} = O(\sqrt{N \log N})$. Our second main result
concerns the joint probability distribution of the random variables $s_N(z^p),\
\nabla s_N(z^p)$, $1\le p\le n$, for $n$ distinct points $z^1,..., z^n$ in a
neighborhood of a point $P_0\in M$. We show that this joint distribution has a
universal scaling limit about $P_0$ as $N \to \infty$. In particular, the limit
is precisely the same as in the complex holomorphic case. Our methods involve
near-diagonal scaling asymptotics of the Szeg\"o projector $\Pi_N$ onto
$H^0_J(M, L^N)$, which also yields proofs of symplectic analogues of the
Kodaira embedding theorem and Tian asymptotic isometry theorem.

</DOC>
<DOC>
<DOCNO> 117430 </DOCNO>
Cosmology with SZ and X-ray cluster surveys


  Hydrodynamical simulations are used in combination with the Press-Schechter
expression to simulate Sunyaev-Zel'dovich (SZ) galaxy cluster sky maps. These
are used to gauge the ability of future SZ observations to provide information
about the cosmological parameters H_0, Omega_M, and the gas fraction f_g in
clusters. This work concentrates on prospects for AMI, the Arcminute
MicroKelvin Imager, a new type of compact interferometric array currently
proposed in Cambridge. The expectations are contrasted with those for X-ray
missions, such as XMM, and the benefits of combining SZ and X-ray data are
highlighted.

</DOC>
<DOC>
<DOCNO> 122130 </DOCNO>
No Persistent Pulsations in Aql X-1 as it Fades into Quiescence


  We searched for coherent X-ray pulsations from Aql X-1 in a series of RXTE
observations taken shortly after a recent outburst. During the course of these
observations, Aql X-1 passes through an apparent ``propeller'' phase as its
luminosity fades to its quiescent value. No pulsations were detected, and we
place upper limits (ranging from 0.52% to 9.0%) on the fractional RMS amplitude
of any periodic signal contained in the various data sets searched. This result
has implications for the geometry of the system, if the quiescent luminosity is
due to continued low-level accretion. Alternatively, our result supports the
idea that the quiescent luminosity may be due to thermal emission.

</DOC>
<DOC>
<DOCNO> 13346 </DOCNO>
Transport Properties Calculation for a Quasi-Bidimensional System using


  We performed a self-consistent calculation using T-Matrix approximation for a
quasi-bidimensional system. We calculated the one particle spectrum function
A(k,\omega) in the presence of strong d-wave attractive interaction. The c-axis
charge dynamics was studied by considering incoherent interlayer hopping and
ab-plane charge dynamics was studied in the coherent limit. It is shown that
the c-axis charge dynamics is mainly governed by the scattering from the in
plane fluctuations. We also present results for c-axis and ab-plane resistivity
and for thermopower coefficient.

</DOC>
<DOC>
<DOCNO> 11008 </DOCNO>
Localization in a random phase-conjugating medium


  We theoretically study reflection and transmission of light in a
one-dimensional disordered phase-conjugating medium. Using an invariant
imbedding approach a Fokker-Planck equation for the distribution of the probe
light reflectance and expressions for the average probabilities of reflection
and transmission are derived. A new crossover length scale for localization of
light is found, which depends on the competition between phase conjugation and
disorder. For weak disorder, our analytical results are in good agreement with
numerical simulations.

</DOC>
<DOC>
<DOCNO> 101506 </DOCNO>
Integral Presentations for the Universal R-matrix


  We present an integral formula for the universal R-matrix of quantum affine
algebra with 'Drinfeld comultiplication'. We show that the properties of the
universal R-matrix follow from the factorization properties of the cycles in
proper configuration spaces. For general g we conjecture that such cycles exist
and unique. For $U_q(\hat{sl}_2)$ describe precisely the cycles and present a
new simple expression for the universal R-matrix as a result of calculation of
corresponding integrals.

</DOC>
<DOC>
<DOCNO> 84427 </DOCNO>
The quantum modes of the (1+1)-dimensional oscillators in general


  The quantum modes of a new family of relativistic oscillators are studied by
using the supersymmetry and shape invariance in a version suitable for (1+1)
dimensional relativistic systems. In this way one obtains the Rodrigues
formulas of the normalized energy eigenfunctions of the discrete spectra and
the corresponding rising and lowering operators.
  Pacs: 04.62.+v, 03.65.Ge

</DOC>
<DOC>
<DOCNO> 68001 </DOCNO>
Analyticity, crossing and the absorptive parts of the one-loop


  Starting from the known one-loop result for the $e^{+}e^{-}$-annihilation
process $e^{+}e^{-}\stackrel{\gamma,Z} {\longrightarrow} q\bar{q}g$ with
massless quarks we employ analyticity and crossing to determine the absorptive
parts of the corresponding one-loop contributions in Deep Inelastic Scattering
(DIS) and in the Drell-Yan process (DY). Whereas the ${\cal O}(\alpha_s^2)$
absorptive parts generate a non-measurable phase factor in the
$e^{+}e^{-}$-annihilation channel one obtains measurable phase effects from the
one-loop contributions in the deep inelastic and in the Drell-Yan case. We
compare our results with the results of previous calculations where the
absorptive parts in DIS and in the DY process were calculated directly in the
respective channels. We also present some new results on the dispersive and
absorptive contributions of the triangle anomaly graph to the DIS process.

</DOC>
<DOC>
<DOCNO> 116643 </DOCNO>
Combining Research Methods and Results from Psychology and Physics in


  Research methods and results from physics and psychology are used to explore
a question in quantum mechanics. In this investigation, an observer variable is
manipulated in an experimental context concerning the trajectory of electrons
affected by their movement through a Stern-Gerlach apparatus. The basis in
psychology concerning why the observer variable is significant in the
experimental context is discussed. This investigation can serve as a prototype
for more complicated investigations.

</DOC>
<DOC>
<DOCNO> 178802 </DOCNO>
Can we determine the nuclear equation of state from heavy ion


  We discuss the problems involved in extracting the nuclear equation-of-state
from heavy-ion collisions. We demonstrate that the equation of state becomes
effectively softer in non-equilibrium and this effect is observable in terms of
collective flow effects. Thus, non-equilibrium effects must be included in
transport descriptions on the level of the effective mean fields. A comparison
with transverse momentum, rapidity, and centrality selected flow data show the
reliability and limitations of the underlying interaction which was derived
from microscopic Dirac-Brueckner (DB) results.

</DOC>
<DOC>
<DOCNO> 120210 </DOCNO>
A Further Analysis of a Cosmological Model of Quintessence and Scalar


  We present the complete solution to a 95% scalar field cosmological model in
which the dark matter is modeled by a scalar field $\Phi$ with the scalar
potential $V(\Phi)=V_{o}[ \cosh {(\lambda \sqrt{\kappa_{o}}\Phi)}-1]$ and the
dark energy is modeled by a scalar field $\Psi$, endowed with the scalar
potential $\tilde{V}(\Psi)=\tilde{V_{o}}[ \sinh {(\alpha
\sqrt{\kappa_{o}}\Psi)}] ^{\beta}$. This model has only two free parameters,
$\lambda$ and the equation of state $\omega_{\Psi}$. With these potentials, the
fine tuning and the cosmic coincidence problems are ameliorated for both dark
matter and dark energy and the models agrees with astronomical observations.
For the scalar dark matter, we clarify the meaning of a scalar Jeans lenght and
then the model predicts a suppression of the Mass Power Spectrum for small
scales having a wave number $k > k_{min,\Phi}$, where $k_{min,\Phi} \simeq 4.5
h {\rm Mpc}^{-1}$ for $\lambda \simeq 20.28$. This last fact could help to
explain the dearth of dwarf galaxies and the smoothness of galaxy core halos.
  From this, all parameters of the scalar dark matter potential are completely
determined. The dark matter consists of an ultra-light particle, whose mass is
$m_{\Phi} \simeq 1.1\times 10^{-23} {\rm eV}$ and all the success of the
standard cold dark matter model is recovered. This implies that a scalar field
could also be a good candidate as the dark matter of the Universe.

</DOC>
<DOC>
<DOCNO> 100322 </DOCNO>
A classification of $S^3$-bundles over $S^4$


  We classify the total spaces of bundles over the four sphere with fiber a
three sphere up to orientation preserving and reversing homotopy equivalence,
homeomorphism and diffeomorphism. These total spaces have been of interest to
both topologists and geometers. It has recently been shown by Grove and Ziller
that each of these total spaces admits metrics with nonnegative sectional
curvature.

</DOC>
<DOC>
<DOCNO> 116448 </DOCNO>
Generalized Optimal Current Patterns and Electrical Safety in EIT


  There are a number of constraints which limit the current and voltages which
can be applied on a multiple drive electrical imaging system. One obvious
constraint is to limit the maximum Ohmic power dissipated in the body. Current
patterns optimising distinguishability with respect to this constraint are
singular functions of the difference of transconductance matrices with respect
to the power norm. (the optimal currents of Isaacson). If one constrains the
total current ($L^1$ norm) the optimal patterns are pair drives. On the other
hand if one constrains the maximum current on each drive electrode (an
$L^\infty$ norm), the optimal patterns have each drive channel set to the
maximum source or sink current value. In this paper we consider appropriate
safety constraints and discuss how to find the optimal current patterns with
those constraints.

</DOC>
<DOC>
<DOCNO> 151404 </DOCNO>
On Theories With Light-Like Noncommutativity


  We show that field theories with light-like noncommutativity, that is with
$\theta^{0i}=-\theta^{1i}$, are unitary quantum theories, and that they can be
obtained as decoupled field theory limits of string theory with D-branes in a
background NS-NS $B$ field. For general noncommutativity parameters, we show
that noncommutative field theories which are unitary can be obtained as
decoupled field theory limits of string theory, while those that are not
unitary cannot be obtained from string theory because massive open strings do
not decouple. We study the different theories with light-like noncommutativity
which arise from Type II D-branes. The decoupling limit of the D4-brane seems
to lead to a noncommutative field theory deformation of the $(2,0)$ SCFT of
M5-branes, while the D5-brane case leads to a noncommutative variation of
``little string theories''. We discuss the DLCQ description of these theories.

</DOC>
<DOC>
<DOCNO> 84219 </DOCNO>
R-mode runaway and rapidly rotating neutron stars


  We present a simple spin evolution model that predicts that rapidly rotating
accreting neutron stars will mainly be confined to a narrow range of
spin-frequencies; P= 1.5-5 ms. This is in agreement with current observations
of both neutron stars in the Low-Mass X-ray Binaries and millisecond
radiopulsars. The main ingredients in the model are; i) the instability of
r-modes above a critical spin rate, ii) thermal runaway due to heat released as
viscous damping mechanisms counteract the r-mode growth, and iii) a revised
estimate of the strength of dissipation due to the presence of a viscous
boundary layer at the base of the crust in an old and relatively cold neutron
star. We discuss the gravitational waves that are radiated during the brief
r-mode driven spin-down phase. We also briefly touch on how the new estimates
affects the predicted initial spin periods of hot young neutron stars.

</DOC>
<DOC>
<DOCNO> 39874 </DOCNO>
Search for new physics with ATLAS at the LHC


  Due to the high energy and luminosity of the LHC, the ATLAS experiment has a
huge discovery potential for new physics. A Standard Model Higgs boson can be
discovered over the full range of allowed masses, and its mass should be
measured with a precision of about 0.1%. The Higgs sector of the MSSM should be
fully explored by searches for supersymmetric Higgs bosons. Squarks and gluinos
can be discovered up to masses of 2.5 TeV and several precision measurements
can be performed in the SUSY sector. The existence of particles predicted by
other theories beyond the Standard Model has been also investigated.

</DOC>
<DOC>
<DOCNO> 13323 </DOCNO>
An alternate model for magnetization plateaus in the molecular magnet


  Starting from an antiferromagnetic Heisenberg Hamiltonian for the fifteen
spin-1/2 ions in V_15, we construct an effective spin Hamiltonian involving
eight low-lying states (spin-1/2 and spin-3/2) coupled to a phonon bath. We
numerically solve the time-dependent Schrodinger equation of this system, and
obtain the magnetization as a function of temperature in a time-dependent
magnetic field. The magnetization exhibits unusual patterns of hysteresis and
plateaus as the field sweep rate and temperature are varied. The observed
plateaus are not due to quantum tunneling but are a result of thermal
averaging. Our results are in good agreement with recent experimental
observations.

</DOC>
<DOC>
<DOCNO> 8973 </DOCNO>
Hydrogen Bonds in Polymer Folding


  The thermodynamics of a homopolymeric chain with both Van der Waals and
highly-directional hydrogen bond interaction is studied. The effect of hydrogen
bonds is to reduce dramatically the entropy of low-lying states and to give
raise to long-range order and to conformations displaying secondary structures.
For compact polymers a transition is found between helix-rich states and
low-entropy sheet-dominated states. The consequences of this transition for
protein folding and, in particular, for the problem of prions are discussed.

</DOC>
<DOC>
<DOCNO> 70309 </DOCNO>
Some Issues in Flat Direction Baryogenesis


  Motivated by recent developments, we explore some issues in Affleck-Dine
baryogenesis. We consider in greater detail the role of thermal effects in the
production of baryon number. We find that these effects are important even for
rather flat potentials, and obtain somewhat different estimates of the baryon
asymmetry than those in the literature. We also consider the decay of the
condensate, and possible implications of these observations for the formation
of Q-balls.

</DOC>
<DOC>
<DOCNO> 12106 </DOCNO>
Neutron Scattering study of Sr_2Cu_3O_4Cl_2


  We report a neutron scattering study on the tetragonal compound
Sr_2Cu_3O_4Cl_2, which has two-dimensional (2D) interpenetrating Cu_I and
Cu_{II} subsystems, each forming a S=1/2 square lattice quantum Heisenberg
antiferromagnet (SLQHA). The mean-field ground state is degenerate, since the
inter-subsystem interactions are geometrically frustrated. Magnetic neutron
scattering experiments show that quantum fluctuations lift the degeneracy and
cause a 2D Ising ordering of the Cu_{II} subsystem. Due to quantum fluctuations
a dramatic increase of the Cu_I out-of-plane spin-wave gap is also observed.
The temperature dependence and the dispersion of the spin-wave energy are
quantitatively explained by spin-wave calculations which include quantum
fluctuations explicitly. The values for the nearest-neighbor superexchange
interactions between the Cu_I and Cu_{II} ions and between the Cu_{II} ions are
determined experimentally to be J_{I-II} = -10(2)meV and J_{II}= 10.5(5)meV,
respectively. Due to its small exchange interaction, J_{II}, the 2D dispersion
of the Cu_{II} SLQHA can be measured over the whole Brillouin zone with thermal
neutrons, and a novel dispersion at the zone boundary, predicted by theory, is
confirmed. The instantaneous magnetic correlation length of the Cu_{II} SLQHA
is obtained up to a very high temperature, T/J_{II}\approx 0.75. This result is
compared with several theoretical predictions as well as recent experiments on
the S=1/2 SLQHA.

</DOC>
<DOC>
<DOCNO> 80943 </DOCNO>
Recent results using the overlap Dirac operator


  I derive the overlap Dirac operator starting from the overlap formalism,
discuss the numerical hurdles in dealing with this operator and present ways to
overcome them.

</DOC>
<DOC>
<DOCNO> 39893 </DOCNO>
Energy Spectra, Altitude Profiles and Charge Ratios of Atmospheric Muons


  We present a new measurement of air shower muons made during atmospheric
ascent of the High Energy Antimatter Telescope balloon experiment. The muon
charge ratio mu+ / mu- is presented as a function of atmospheric depth in the
momentum interval 0.3-0.9 GeV/c. The differential mu- momentum spectra are
presented between 0.3 and about 50 GeV/c at atmospheric depths between 13 and
960 g/cm^2. We compare our measurements with other recent data and with Monte
Carlo calculations of the same type as those used in predicting atmospheric
neutrino fluxes. We find that our measured mu- fluxes are smaller than the
predictions by as much as 70% at shallow atmospheric depths, by about 20% at
the depth of shower maximum, and are in good agreement with the predictions at
greater depths. We explore the consequences of this on the question of
atmospheric neutrino production.

</DOC>
<DOC>
<DOCNO> 13393 </DOCNO>
Complexation of a polyelectrolyte with oppositely charged spherical


  Complexation of a long flexible polyelectrolyte (PE) molecule with oppositely
charged spherical particles such as colloids, micelles, or globular proteins in
a salty water solution is studied. PE binds spheres winding around them, while
spheres repel each other and form almost periodic necklace. If the total charge
of PE is larger than the total charge of spheres, repulsive correlations of PE
turns on a sphere lead to inversion of the net charge of each sphere. In the
opposite case, we predict another correlation effect: under-screened by PE
spheres bind to PE in such a great number that they invert charge of PE. The
inverted charge by absolute value can be larger than the bare charge of PE even
when screening by monovalent salt is weak. At larger concentrations of
monovalent salt, the inverted charge can reach giant proportions. Our theory is
in qualitative agreement with recent experiments on micelles-PE systems.

</DOC>
<DOC>
<DOCNO> 70203 </DOCNO>
Three Generation Long-wavelength Vacuum Oscillation Solution to the


  We investigate the current status of the long-wavelength vacuum oscillation
solution to the solar neutrino problem and to what extent the presence of a
third neutrino can affect and modify it. Assuming that the smaller mass squared
difference that can induce such oscillations, $\Delta m^2_{12}$, is in the
range $10^{-11}-10^{-8}$ eV$^2$ and the larger one, $\Delta m^2_{23}$, in the
range relevant to atmospheric neutrino observations, we analyze the most recent
solar neutrino data coming from Homestake, SAGE, GALLEX, GNO and
Super-Kamiokande experiments in the context of three neutrino generations. We
include in our vacuum oscillation analysis the MSW effect in the Sun, which is
relevant for some of the parameter space scrutinized. We have also performed,
as an extreme exercise, the fit without Homestake data. % While we found that
the MSW effect basically does not affect the best fitted parameters, it
significantly modifies the allowed parameter space for $\Delta m^2_{12}$ larger
than $\sim 3 \times 10^{-10}$ eV$^2$, in good agreement with the result
obtained by A. Friedland in the case of two generations. % Although the
presence of a third neutrino does not essentially improve the quality of the
fit, the solar neutrino data alone can give an upper bound on $\theta_{13}$,
which is constrained to be less than $\sim 60^\circ$ at 95 % C.L.

</DOC>
<DOC>
<DOCNO> 119990 </DOCNO>
Timing the Kilohertz Quasi-Periodic Oscillations in Low-mass X-ray


  I describe a new technique that we have been using in the past few years to
get precise measurements of the frequency separation of the kHz QPOs in some
Low-mass X-ray binaries. I show how this technique (that we call
"shift-and-add") works, and I present some of the results we obtained using it.

</DOC>
<DOC>
<DOCNO> 151096 </DOCNO>
The c-Functions of Noncommutative Yang-Mills Theory from Holography


  In this paper we study non-commutative Yang-Mills theory (NCYM) through its
gravity dual. First it is shown that the gravity dual of an NCYM with self-dual
$\theta$-parameters has a Lagrangian in the form of five-dimensional dilatonic
gravity. Then we use the de-Boer-Verlinde-Verlinde formalism for holographic
renormalization group flows to calculate the coefficient functions in the Weyl
anomaly of the NCYM at low energies under the assumption of potential
dominance, and show that the $C$-theorem holds true in the present case.

</DOC>
<DOC>
<DOCNO> 116732 </DOCNO>
Equations for Stochastic Macromolecular Mechanics of Single Proteins:


  A modeling framework for the internal conformational dynamics and external
mechanical movement of single biological macromolecules in aqueous solution at
constant temperature is developed. Both the internal dynamics and external
movement are stochastic; the former is represented by a master equation for a
set of discrete states, and the latter is described by a continuous
Smoluchowski equation. Combining these two equations into one, a comprehensive
theory for the Brownian dynamics and statistical thermodynamics of single
macromolecules arises. This approach is shown to have wide applications. It is
applied to protein-ligand dissociation under external force, unfolding of
polyglobular proteins under extension, movement along linear tracks of motor
proteins against load, and enzyme catalysis by single fluctuating proteins. As
a generalization of the classic polymer theory, the dynamic equation is capable
of characterizing a single macromolecule in aqueous solution, in probabilistic
terms, (1) its thermodynamic equilibrium with fluctuations, (2) transient
relaxation kinetics, and most importantly and novel (3) nonequilibrium
steady-state with heat dissipation. A reversibility condition which guarantees
an equilibrium solution and its thermodynamic stability is established, an
H-theorem like inequality for irreversibility is obtained, and a rule for
thermodynamic consistency in chemically pumped nonequilibrium steady-state is
given.

</DOC>
<DOC>
<DOCNO> 119570 </DOCNO>
Acceleration time scale in an ultrarelativistic shock


  The acceleration mechanism at ultrarelativistic shocks is investigated using
the Monte Carlo simulations. We apply a method of discrete small amplitude
particle momentum scattering to reproduce highly anisotropic conditions at the
shock and carefully describe the acceleration mechanism. The obtained
acceleration times equal $1.0 r_{g}/c$ if the spectral index reach the value of
2.2, independent of physical conditions in the shock. Some other parameters of
the acceleration process are also provided.

</DOC>
<DOC>
<DOCNO> 85553 </DOCNO>
Remarks on vacuum fluctuations around a spinning cosmic string


  We apply the point-splitting method to investigate vacuum fluctuations in the
nonglobally hyperbolic background of a spinning cosmic string. Implementing
renormalization by removing the Minkowski contribution it is shown that
although the Green function in the literature satisfies the usual Green
function equation, it leads to pathological physical results.

</DOC>
<DOC>
<DOCNO> 116621 </DOCNO>
Efficient Dynamic Importance Sampling of Rare Events in One Dimension


  Exploiting stochastic path integral theory, we obtain \emph{by simulation}
substantial gains in efficiency for the computation of reaction rates in
one-dimensional, bistable, overdamped stochastic systems. Using a well-defined
measure of efficiency, we compare implementations of ``Dynamic Importance
Sampling'' (DIMS) methods to unbiased simulation. The best DIMS algorithms are
shown to increase efficiency by factors of approximately 20 for a $5 k_B T$
barrier height and 300 for $9 k_B T$, compared to unbiased simulation. The
gains result from close emulation of natural (unbiased), instanton-like
crossing events with artificially decreased waiting times between events that
are corrected for in rate calculations. The artificial crossing events are
generated using the closed-form solution to the most probable crossing event
described by the Onsager-Machlup action. While the best biasing methods require
the second derivative of the potential (resulting from the ``Jacobian'' term in
the action, which is discussed at length), algorithms employing solely the
first derivative do nearly as well. We discuss the importance of
one-dimensional models to larger systems, and suggest extensions to
higher-dimensional systems.

</DOC>
<DOC>
<DOCNO> 102849 </DOCNO>
Relation between quantum invariants of 3-manifolds and 2-dimensional


  We show that the Reshetikhin-Turaev-Walker invariant of 3-manifolds can be
normalized to obtain an invariant of 4-dimensional thickenings of 2-complexes.
Moreover when the underlying semisimple tortile category comes from the
representations of a quantum group at a primitive prime root of unity, the
0-term in the Ohtsuki expansion of this invariant depends only on the spine and
is the mod p invariant of 2-complexes defined previously from the second
author. As a consequence it is shown that when the Euler characteristic is
greater or equal to 1, the 2-complex invariant depends only on homology. The
last statement doesn't hold for the negative Euler characteristic case.

</DOC>
<DOC>
<DOCNO> 10044 </DOCNO>
Kuehn and Mazzeo Reply


  We reply to a comment of Van Enter, Kuelske and Maes (cond-mat/0005176) on
our letter "Critical Behavior of the Randomly Spin-Diluted 2-d Ising Model - A
Grand Ensemble Approach", Phys. Rev. Lett. {\bf 73}, 2268-2271 (1994).

</DOC>
<DOC>
<DOCNO> 80849 </DOCNO>
Damping and the Hartree Ensemble Approximation


  We study a Hartree ensemble approximation for real-time dynamics in the toy
model of 1+1 dimensional scalar field theory. Damping behavior seen in
numerical simulations is compared with analytical predictions based on
perturbation theory in the original (non-Hartree-approximated) model.

</DOC>
<DOC>
<DOCNO> 9155 </DOCNO>
Polymer Principles of Protein Calorimetric Two-State Cooperativity


  The experimental calorimetric two-state criterion requires the van't Hoff
enthalpy $\Delta H_{\rm vH}$ around the folding/unfolding transition midpoint
to be equal or very close to the calorimetric enthalpy $\Delta H_{\rm cal}$ of
the entire transition. We use an analytical model with experimental parameters
from chymotrypsin inhibitor 2 to elucidate the relationship among several
different van't Hoff enthalpies used in calorimetric analyses. Under reasonable
assumptions, the implications of these $\Delta H_{\rm vH}$'s being
approximately equal to $\Delta H_{\rm cal}$ are equivalent: Enthalpic
variations among denatured conformations in real proteins are much narrower
than some previous lattice-model estimates, suggesting that the energy
landscape theory ``folding to glass transition temperature ratio'' $T_{\rm
f}/T_{\rm g}$ may exceed 6.0 for real calorimetrically two-state proteins.
Several popular three-dimensional lattice protein models, with different
numbers of residue types in their alphabets, are found to fall short of the
high experimental standard for being calorimetrically two-state. Some models
postulate a multiple-conformation native state with substantial
pre-denaturational energetic fluctuations well below the unfolding transition
temperature and/or predict a significant post-denaturational continuous
conformational expansion of the denatured ensemble at temperatures well above
the transition point.

</DOC>
<DOC>
<DOCNO> 40596 </DOCNO>
Lorentz Angle Measurement for CO2/Isobutane Gas Mixtures


  We have developed a Lorentz angle measurement system for cool gas mixtures in
the course of our R&D for a proposed JLC central drift chamber (JLC-CDC). The
measurement system is characterized by the use of two laser beams to produce
primary electrons and flash ADCs to read their signals simultaneously. With
this new system, we have measured Lorentz angles for CO2/isobutane gas mixtures
with different proportions (95:5, 90:10, and 85:15), varying drift field from
0.6 to 2.0 kV/cm and magnetic field up to 1.5 T. The results of the measurement
are in good agreement with GARFIELD/MAGBOLTZ simulations.

</DOC>
<DOC>
<DOCNO> 84646 </DOCNO>
Multipole Moments of Static Spacetimes


  This paper reviews work, largely due to W. Simon and the author, on multipole
theory of static spacetimes. The main purpose is to make this work, which lies
at the interface of potential theory, conformal geometry and general
relativity, known to mathematicians and to perhaps motivate them to look at the
open problems which still remain.

</DOC>
<DOC>
<DOCNO> 10885 </DOCNO>
Microscopic dynamics underlying the anomalous diffusion


  The time dependent Tsallis statistical distribution describing anomalous
diffusion is usually obtained in the literature as the solution of a non-linear
Fokker-Planck (FP) equation [A.R. Plastino and A. Plastino, Physica A, 222, 347
(1995)]. The scope of the present paper is twofold. Firstly we show that this
distribution can be obtained also as solution of the non-linear porous media
equation. Secondly we prove that the time dependent Tsallis distribution can be
obtained also as solution of a linear FP equation [G. Kaniadakis and P.
Quarati, Physica A, 237, 229 (1997)] with coefficients depending on the
velocity, that describes a generalized Brownian motion. This linear FP equation
is shown to arise from a microscopic dynamics governed by a standard Langevin
equation in presence of multiplicative noise.

</DOC>
<DOC>
<DOCNO> 120820 </DOCNO>
Comptonization of Infrared Radiation from Hot Dust by Relativistic Jets


  We demonstrate the importance of near-infrared radiation from hot dust for
Compton cooling of electrons/positrons in quasar jets. In our model, we assume
that the non-thermal radiation spectra observed in OVV quasars are produced by
relativistic electrons/positrons accelerated in thin shells which propagate
down the jet with relativistic speeds. We show that the Comptonization of the
near-IR flux is likely to dominate the radiative output of OVV quasars in the
energy range from tens of keV up to hundreds of MeV, where it exceeds that
produced by Comptonization of the UV radiation reprocessed and rescattered in
the Broad Emission Line region. The main reason for this lies in the fact that
the jet encounters the ambient IR radiation over a relatively large distance as
compared to the distance where the energy density of the broad emission line
light peaks. In the soft - to mid energy X-ray band, the spectral component
resulting from Comptonization of the near-IR radiation joins smoothly with the
synchrotron-self-Compton component, which may be responsible for the soft X-ray
flux. At the highest observed gamma-ray energies, in the GeV range,
Comptonization of broad emission lines dominates over other components.

</DOC>
<DOC>
<DOCNO> 121090 </DOCNO>
The evolution of main sequence star + white dwarf binary systems towards


  Close binaries consisting of a main sequence star and a white dwarf are
considered as candidates for Type~Ia supernova progenitors. We present
selfconsistent calculations of the time dependence of the structure of the main
sequence star, the mass transfer rate, and the orbit by means of a binary
stellar evolution program. In contrast to results based on simple estimates of
the mass transfer rate in systems of the considered type, our results allow for
the possibility that even systems with rather small initial white dwarf masses
(~ 0.7 M_sun) may produce Type Ia supernovae. We present results for two
different metallicities, Z=0.02 and Z=0.001. We find that for systems with the
lower metallicity, the mass transfer rates are on average five times larger
than in comparable system at solar metallicity. This leads to a systematic
shift of the supernova Ia progenitor population. Firstly, while for Z=0.02
donor star initial masses in supernova progenitor systems are restricted to the
range 1.6...2.3 M_sun, they are in the interval 1.4...1.8 M_sun at low Z.
Secondly, the initial white dwarf masses need, on average, to be larger by 0.2
M_sun at low Z in order to obtain a Chandrasekhar mass white dwarf. This
metallicity dependences may be responsible for a drop of the Type Ia supernova
rate for low metallicity, and may introduce a Z-dependence in the properties of
supernovae. We also estimate the X-ray luminosities of the computed systems,
and investigate their donor star and orbital properties.

</DOC>
<DOC>
<DOCNO> 70696 </DOCNO>
QCD dipole model and k_T factorization


  It is shown that the colour dipole approach to hard scattering at high energy
is fully compatible with k_T factorization at the leading logarithm
approximation (in -log x_Bj). The relations between the dipole amplitudes and
unintegrated diagonal and non-diagonal gluon distributions are given. It is
also shown that including the exact gluon kinematics in the k_T factorization
formula destroys the conservation of transverse position vectors and thus is
incompatible with the dipole model for both elastic and diffractive amplitudes.

</DOC>
<DOC>
<DOCNO> 71576 </DOCNO>
Dimensional Regularization and Mellin Summation in High-Temperature


  A general method for calculating asymptotic expansions of infinite sums in
thermal field theory is presented. It is shown that the Mellin summation method
works elegantly with dimensional regularization. A general result is derived
for a class of one-loop Feynman diagrams at finite-temperature.

</DOC>
<DOC>
<DOCNO> 8976 </DOCNO>
Conformal Profiles in the Hilhorst--van Leeuwen Model


  We study the critical energy and magnetization profiles for the Ising quantum
chain with a marginal extended surface perturbation of the form A/y, y being
the distance from the surface (Hilhorst-van Leeuwen model). For weak local
couplings, A<A_c, the model displays a continuous surface transition with
A-dependent exponents, whereas, for A>A_c, there is surface order at the bulk
critical point. If conformal invariance is assumed to hold with such marginal
perturbations, it predicts conformal profiles with the same scaling form as for
the unperturbed quantum chain, with marginal surface exponents replacing the
unperturbed ones. The results of direct analytical and numerical calculations
of the profiles confirm the validity of the conformal expressions in the
regimes of second- and first-order surface transitions.

</DOC>
<DOC>
<DOCNO> 9512 </DOCNO>
Transport and Elastic Properties of Fractal Media


  We investigate the influence of fractal structure on material properties. We
calculate the statistical correlation functions of fractal media defined by
level-cut Gaussian random fields. This allows the modeling of both surface
fractal and mass fractal materials. Variational bounds on the conductivity,
diffusivity and elastic moduli of the materials are evaluated. We find that a
fractally rough interface has a relatively strong influence on the properties
of composites. In contrast a fractal volume (mass) has little effect on
material properties.

</DOC>
<DOC>
<DOCNO> 119051 </DOCNO>
Asymmetries of Secondary Cosmic Muons with High Statistics and Low


  Project GRAND measures the asymmetries of secondary cosmic muons by
calculating the differences between the muons from the east and the muons from
the west for complete solar days. A similar north-south difference is also
presented. These muons are identified in single track data taken with the 64
stations of Project GRAND; the data cover a two year span with a total muon
sample of 30 billion muons.

</DOC>
<DOC>
<DOCNO> 8339 </DOCNO>
Resonant Spin Excitation in an Overdoped High Temperature Superconductor


  An inelastic neutron scattering study of overdoped Bi_2Sr_2CaCu_2O_{8+\delta}
$ (T_c = 83 K) has revealed a resonant spin excitation in the superconducting
state. The mode energy is E_res=38 meV, significantly lower than in optimally
doped Bi_2Sr_2CaCu_2O_{8+\delta} (T_c = 91 K, E_ res =43 meV). This
observation, which indicates a constant ratio E_res /k_B T_c \sim 5.4, helps
resolve a long-standing controversy about the origin of the resonant spin
excitation in high-temperature superconductors.

</DOC>
<DOC>
<DOCNO> 71044 </DOCNO>
A CP-Violating Kinematic Structure


  A CP violating kinematic structure is presented. The essential physical input
is to question the textbook wisdom, ``Now when a particle is at rest, one
cannot define its spin as either left- or right-handed, so phi_R(0) =
phi_L(0),'' as found, e.g., in Lewis Ryder's Quantum Field Theory, and in many
other books on the representations of the Lorentz group. It is suggested that
this equality is true only up to a phase. The demand of C, P, and T
covariances, separately, fixes this phase to be pm 1. If these conditions are
relaxed, a natural CP-violating kinematic structure emerges. Having established
a CP-violating kinematic structure, we then discuss how Planck scale physics
necessarily invokes non-commutative space-time and that such changes in the
structure of space-time will force upon us additional violations/deformations
of the CPT structure of space-time, and a violation of the principle of
equivalence via a violation of the Lorentz symmetries. The latter may carry
significant consequences for understanding the data on ultra high energy cosmic
rays.

</DOC>
<DOC>
<DOCNO> 151243 </DOCNO>
Light as Caused by Neither by Bound States nor by Neutrinos


  Participants of this workshop pursue the old Neutrino Theory of Light
vigorously. Other physicists have long ago abandoned it, because it lacks gauge
invariance. In the recent Quantum Induction (QI), all basic Bose fields
${\mathcal B}^{P}$ are local limits of quantum fields composed of Dirac's
$\Psi$ (for leptons and quarks). The induced field equations of QI even
determine all the interactions of those ${\mathcal B}^{P}$. Thus a precise
gauge invariance and other physical consequences are unavoidable. They include
the absence of divergencies, the exclusion of Pauli terms, a prediction of the
Higgs mass and a `minimal' Quantum Gravity.
  As we find in this paper, however, photons can't be bound states while
Maxwell's potential $A_{\mu}$ contains all basic Dirac fields except those of
neutrinos.

</DOC>
<DOC>
<DOCNO> 117887 </DOCNO>
CHVCs: Galactic Building Blocks at z = 0


  A distinct sub-class of anomalous velocity HI emission features has emerged
from recent high quality surveys of the Local Group environment, namely the
compact high velocity clouds (CHVCs). A program of high-resolution imaging with
the Westerbork array and the Arecibo telescope has begun to provide many
insights into the nature of these objects. Elongated core components with a
velocity gradient consistent with rotation (V_Rot ~ 15 km/s) are seen in many
objects. Comparison of volume and column densities has allowed the first
distance estimates to be made (600+/-300 kpc). The objects appear to be
strongly dark-matter dominated with dark-to-gas mass ratios of 30-50 implied if
the typical distance is 700 kpc.

</DOC>
<DOC>
<DOCNO> 151128 </DOCNO>
Killing Spinors and SYM on Curved Spaces


  We construct two families of globally supersymmetric counterparts of standard
Poincar\'e supersymmetric SYM theories on curved space-times admitting Killing
spinors, in all dimensions less than six and eight respectively. The former
differs from the standard theory only by mass terms for the fermions and
scalars and modified supersymmetry transformation rules, the latter in addition
has cubic Chern-Simons like couplings for the scalar fields. We partially
calculate the supersymmetry algebra of these models, finding R-symmetry
extensions proportional to the curvature. We also show that generically these
theories have no continuous Coulomb branch of maximally supersymmetric vacua,
but that there exists a half-BPS Coulomb branch approaching the standard
Coulomb branch in the Ricciflat limit.

</DOC>
<DOC>
<DOCNO> 120703 </DOCNO>
Near-infrared and Br_gamma observations of post-AGB stars


  We investigate the infrared properties of the IRAS sources not confirmed as
PNe in Van de Steene & Pottasch (1993). We observed 28 objects in the N-band of
which 20 were detected and 5 were resolved. We obtained medium resolution
Br_gamma spectra and we took high resolution JHKL images of these 20 objects.
We critically assessed the identification of the IRAS counterpart in the
images. Of sixteen positively identified objects, seven show Br_gamma in
absorption, another six objects show Br_gamma in emission on top of a
continuum. In another three objects, no clear Br_gamma absorption or emission
was visible. Our detection rate of emission line objects is higher compared to
previous studies. None of the objects with Br_gamma in emission were detected
above a detection limit of 0.6 mJy/beam at 6 cm, while they should have been
easily detected if the radio flux was optically thin and Case B recombination
was applicable. Their SED's are typical for post-AGB stars. We also constructed
various color-color diagrams using the near-infrared and IRAS magnitudes. No
distinction can be made between the objects showing Br_gamma in emission,
absorption, or a flat spectrum in the near and far-infrared color-color
diagrams. The near-infrared color-color diagrams show evidence for a very large
range of extinction, which in part is of circumstellar origin. Near-infrared
versus far-infrared color-color diagrams show trends that are consistent with
the expected evolution of the circumstellar shell. This sample of post-AGB
stars show a larger range in color and are generally closer to the galactic
plane than the ones known so far.

</DOC>
<DOC>
<DOCNO> 83480 </DOCNO>
Provably Fast and Accurate Recovery of Evolutionary Trees through


  We give a greedy learning algorithm for reconstructing an evolutionary tree
based on a certain harmonic average on triplets of terminal taxa. After the
pairwise distances between terminal taxa are estimated from sequence data, the
algorithm runs in O(n^2) time using O(n) work space, where n is the number of
terminal taxa. These time and space complexities are optimal in the sense that
the size of an input distance matrix is n^2 and the size of an output tree is
n. Moreover, in the Jukes-Cantor model of evolution, the algorithm recovers the
correct tree topology with high probability using sample sequences of length
polynomial in (1) n, (2) the logarithm of the error probability, and (3) the
inverses of two small parameters.

</DOC>
<DOC>
<DOCNO> 69493 </DOCNO>
Light vector meson photoproduction at high $|t|$


  We have studied in perturbative QCD all independent helicity amplitudes
describing the photoproduction of light vector mesons at large $t$. We found a
new hard production mechanism which is related to the possibility for a real
photon to fluctuate into a massless $q\bar q$ pair in a chiral-odd spin
configuration. Each helicity amplitude is given as a sum of chiral-even
contribution (when the helicities of quark and antiquark are antiparallel) and
this additional chiral-odd part (where the helicities of quark and antiquark
are parallel). The chiral-odd contribution is large, it leads to a dominance of
the non spin-flip amplitude in a very broad region of intermediately high
$|t|$.}

</DOC>
<DOC>
<DOCNO> 121146 </DOCNO>
Complex Spectral Variability from Intensive Multi-wavelength Monitoring


  We conducted a multi-frequency campaign for the TeV blazar Mrk~421 in 1998
April. The campaign started from a pronounced high amplitude flare recorded by
SAX and Whipple; ASCA observation started three days later. In the X-ray data,
we detected multiple flares, occuring on time scales of about one day. ASCA
data clearly reveal spectral variability. The comparison of the data from ASCA,
EUVE and RXTE indicates that the variability amplitudes in the low energy
synchrotron component are larger at higher photon energies. In TeV Gamma-rays,
large intra-day variations -- which were correlated with the X-ray flux -- were
observed when results from three Cherenkov telescopes are combined. The RMS
variability of TeV Gamma--rays was similar to that observed in hard X-rays,
above 10 keV. The X-ray light curve reveals flares which are almost symmetric
for most of cases, implying the dominant time scale is the light crossing time
through the emitting region. The structure function analysis based on the
continuous X-ray light curve of seven days indicates that the characteristic
time scale is ~0.5 day. The analysis of ASCA light curves in various energy
bands appears to show both soft (positive) and hard (negative) lags. These may
not be real, as systematic effects could also produce these lags, which are all
much smaller than an orbit. If the lags of both signs are real, these imply
that the particle acceleration and X-ray cooling time scales are similar.

</DOC>
<DOC>
<DOCNO> 13842 </DOCNO>
Phase fluctuations and the pseudogap in YBa2Cu3Ox


  The thermodynamics of the superconducting transition is studied as a function
of doping using high-resolution expansivity data of YBa2Cu3Ox single crystals
and Monte-Carlo simulations of the anisotropic 3D-XY model. We directly show
that Tc of underdoped YBa2Cu3Ox is strongly suppressed from its mean-field
value (Tc-MF) by phase fluctuations of the superconducting order parameter. For
overdoped YBa2Cu3Ox fluctuation effects are greatly reduced and Tc ~ Tc-MF . We
find that Tc-MF exhibits a similar doping dependence as the pseudogap energy,
naturally suggesting that the pseudogap arises from phase-incoherent Cooper
pairing.

</DOC>
<DOC>
<DOCNO> 85608 </DOCNO>
On a Peculiar Family of Static, Axisymmetric, Vacuum Solutions of the


  The Zipoy-Voorhees family of static, axisymmetric vacuum solutions forms an
interesting family in that it contains the Schwarzschild black hole excepting
which all other members have naked singularity. We analyze some properties of
the region near singularity by studying a natural family of 2-surfaces. We
establish that these have the topology of the 2-sphere by an application of the
Gauss-Bonnet theorem. By computing the area, we establish that the singular
region is `point-like'. Isometric embedding of these surfaces in the three
dimensional Euclidean space is used to distinguish the two types of deviations
from spherical symmetry.

</DOC>
<DOC>
<DOCNO> 116259 </DOCNO>
Statistical mechanics of neocortical interactions: High resolution


  We present high-resolution path-integral calculations of a previously
developed model of short-term memory in neocortex. These calculations, made
possible with supercomputer resources, supplant similar calculations made in L.
Ingber, Phys. Rev. E 49, 4652 (1994), and support coarser estimates made in L.
Ingber, Phys. Rev. A 29, 3346 (1984). We also present a current experimental
context for the relevance of these calculations using the approach of
statistical mechanics of neocortical interactions, especially in the context of
electroencephalographic data.

</DOC>
<DOC>
<DOCNO> 85130 </DOCNO>
Einstein Manifolds, Abelian Instantons, Bundle Reduction, and the


  The anti-self-dual projection of the spin connections of certain
four-dimensional Einstein manifolds can be Abelian in nature. These
configurations signify bundle reductions. By a theorem of Kobayashi and Nomizu
such a process is predicated on the existence of a covariantly constant field.
It turns out that even without fundamental Higgs fields and other physical
matter, gravitational self-interactions can generate this mechanism if the
cosmological constant is non-vanishing. This article identifies the order
parameter, and clarifies how these Abelian instanton solutions are associated
with a Higgs triplet which causes the bundle reduction from SO(3) gauge group
to U(1).

</DOC>
<DOC>
<DOCNO> 72149 </DOCNO>
Hard Exclusive Production of Tensor Mesons


  We point out that hard exclusive production of tensor mesons $f_2(1270)$ with
helicity $\lambda=\pm 2$ is dominated by the gluon component in the meson wave
function and can be used to determine gluon admixture in tensor mesons in a
theoretically clean manner.
 We present a detailed analysis of the tensor meson distribution amplitudes and
calculate the transition form factor $\gamma+\gamma^*\to f_2(1270)$ for one
real and one virtual photon.

</DOC>
<DOC>
<DOCNO> 122418 </DOCNO>
Supernova 1991T and the Value of the Hubble Constant


  Based upon multi-epoch Hubble Space Telescope observations, we present the
discovery of sixteen high-quality Cepheid candidates in NGC 4527. Corrected for
metallicity effects in the Cepheid period-luminosity relation, we derive a
distance, including both random (r) and systematic (s) uncertainties, of
13.0+/-0.5(r)+/-1.2(s) Mpc. Our result is then used to provide a calibration of
the peak B-, V-, and I-band luminosities of the peculiar Type Ia supernova SN
1991T, a resident of NGC 4527. Despite its documented spectroscopic
peculiarities, after correction for the decline rate-luminosity correlation the
corrected peak luminosity is indistinguishable from those of so-called
``normal'' Type Ia SNe. With now nine local calibrators at our disposal, we
determine a robust value for the Hubble Constant of H_0=73+/-2(r)+/-7(s)
km/s/Mpc.

</DOC>
<DOC>
<DOCNO> 68945 </DOCNO>
Effects of Large CP Phases on the Proton Lifetime in Supersymmetric


  The effects of large CP violating phases arising from the soft SUSY breaking
parameters on the proton lifetime are investigated in supersymmetric grand
unified models. It is found that the CP violating phases can reduce as well as
enhance the proton lifetime depending on the part of the parameter space one is
in. Modifications of the proton lifetime by as much as a factor of 2 due to the
effects of the CP violating phases are seen. The largest effects arise for the
lightest sparticle spectrum in the dressing loop integrals and the effects
decrease with the increasing scale of the sparticle masses. An analysis of the
uncertainties in the determination of the proton life time due to uncertainties
in the quark masses and in the other input data is also given. These results
are of import in the precision predictions of the proton lifetime in
supersymmetric unification both in GUT and in string models when the soft SUSY
breaking parameters are complex.

</DOC>
<DOC>
<DOCNO> 11831 </DOCNO>
Higher order glass-transition singularities in colloidal systems with


  The transition from a liquid to a glass in colloidal suspensions of particles
interacting through a hard core plus an attractive square-well potential is
studied within the mode-coupling-theory framework. When the width of the
attractive potential is much shorter than the hard-core diameter, a reentrant
behavior of the liquid-glass line, and a glass-glass-transition line are found
in the temperature-density plane of the model. For small well-width values, the
glass-glass-transition line terminates in a third order bifurcation point, i.e.
in a A_3 (cusp) singularity. On increasing the square-well width, the
glass-glass line disappears, giving rise to a fourth order A_4 (swallow-tail)
singularity at a critical well width. Close to the A_3 and A_4 singularities
the decay of the density correlators shows stretching of huge dynamical
windows, in particular logarithmic time dependence.

</DOC>
<DOC>
<DOCNO> 101297 </DOCNO>
Destruction of CD4 T Lymphocytes Alone Cannot Account for their


  Following previous models describing a quasi steady state (QSS) for the
evolution of HIV infection and AIDS, we have developed a larger formalism
simulating the long-term evolution of the QSS We show that the long-term
evolution of AIDS cannot be explained by the destruction alone of CD4 T cells,
either directly or indirectly. The destruction of CD4 T cells can lead only to
a QSS with a lower concentration of CD4 T cells, but CD4 destruction cannot
generate the sustained long-term decrease in T cells leading to AIDS. We here
suggest some workable explanations.

</DOC>
<DOC>
<DOCNO> 169576 </DOCNO>
Anharmonic oscillators energies via artificial perturbation method


  A new pseudoperturbative (artificial in nature) methodical proposal [15] is
used to solve for Schrodinger equation with a class of phenomenologically
useful and methodically challenging anharmonice oscillator potentials
V(q)=\alpha_o q^2 + \alpha q^4. The effect of the [4,5] Pade' approximant on
the leading eigenenergy term is studied. Comparison with results from numerical
(exact) and several eligible (approximation) methods is made.

</DOC>
<DOC>
<DOCNO> 123010 </DOCNO>
Young Collapsed Supernova Remnants: Similarities and Differences in


  Type Ia supernovae are thought to explode completely, leaving no condensed
remnant, only an expanding shell. Other types of supernovae are thought to
involve core collapse and are expected to leave a condensed remnant, which
could be either a neutron star or a black hole, or just possibly, something
more exotic, such as a quark orstrange star, a naked singularity, a frozen
star, a wormhole or a red hole. It has proven surprisingly difficult to
determine which type of condensed remnant has been formed in those cases where
the diagnostic highly regular pulsar signature of a neutron star is absent. We
consider possible observational differences between the two standard
candidates, as well as the more speculative alternatives.
  We classify condensed remnants according to whether they do or do not possess
three major features: 1)a hard surface, 2)an event horizon, and 3)a
singularity. Black holes and neutron stars differ on all three criteria. Some
of the less frequently considered alternatives are "intermediate," in the sense
that they possess some of the traits of a black hole and some of the traits of
a neutron star. This possibility makes distinguishing the various possibilities
even more difficult.

</DOC>
<DOC>
<DOCNO> 150526 </DOCNO>
Non-Abelian Field Theory of stable non-BPS Branes


  We derive the action for the non-abelian field theory living on parallel
non-BPS D3-branes in type IIA theory on the orbifold T^4/I_4(-1)^F_L. The
classical moduli space for the massless scalars originating in the ``would be''
tachyonic sector shows an interesting structure. In particular, it contains
non-abelian flat directions. At a generic point in this branch of the moduli
space the scalars corresponding to the the separations of the branes acquire
masses and the branes condense. Although these tree level flat directions are
removed by quantum corrections we argue that within the loop approximation the
branes still condense.

</DOC>
<DOC>
<DOCNO> 67908 </DOCNO>
Baryogenesis and Degenerate Neutrinos


  We bring the theoretical issue of whether two important cosmological demands,
baryon asymmetry and degenerate neutrinos as hot dark matter, can be compatible
in the context of the seesaw mechanism. To realize leptogenesis with almost
degenerate Majorana neutrinos without severe fine-tuning of parameters, we
propose the hybrid seesaw mechanism with a heavy Higgs triplet and right-handed
neutrinos. Constructing a minimal hybrid seesaw model with SO(3) flavor
symmetry for the neutrino sector, we show that the mass splittings for the
atmospheric and solar neutrino oscillations which are consistent with the
requirements for leptogenesis can naturally arise.

</DOC>
<DOC>
<DOCNO> 118849 </DOCNO>
BeppoSAX observation of Cen X-4 in quiescence


  We report on a 61 ks BeppoSAX observation of the soft X-ray transient Cen X-4
during quiescence which allowed to study the source X-ray spectrum from ~ 0.3
keV to ~ 8 keV. A two-component spectral model was required, consisting of a
black body with temperature of ~ 0.1 keV and a power law with photon index ~ 2.
These values are compatible with earlier ASCA results indicating that Cen X-4
may be stable, within a factor of a few, over a 5 year baseline.

</DOC>
<DOC>
<DOCNO> 150328 </DOCNO>
Super-Poincare Covariant Quantization of the Superstring


  Using pure spinors, the superstring is covariantly quantized. For the first
time, massless vertex operators are constructed and scattering amplitudes are
computed in a manifestly ten-dimensional super-Poincar\'e covariant manner.
Quantizable non-linear sigma model actions are constructed for the superstring
in curved backgrounds, including the $AdS_5\times S^5$ background with
Ramond-Ramond flux.

</DOC>
<DOC>
<DOCNO> 85182 </DOCNO>
On the "renormalization" transformations induced by cycles of expansion


  We study the ``renormalization group action'' induced by cycles of cosmic
expansion and contraction, within the context of a family of stochastic
dynamical laws for causal sets derived earlier. We find a line of fixed points
corresponding to the dynamics of transitive percolation, and we prove that
there exist no other fixed points and no cycles of length two or more. We also
identify an extensive ``basin of attraction'' of the fixed points but find that
it does not exhaust the full parameter space. Nevertheless, we conjecture that
every trajectory is drawn toward the fixed point set in a suitably weakened
sense.

</DOC>
<DOC>
<DOCNO> 100556 </DOCNO>
Sylvester Waves in the Coxeter Groups


  A new recursive procedure of the calculation of partition numbers function
$W(s,{\bf d}^m)$ is suggested. We find its zeroes and prove a lemma on the
function parity properties. The explicit formulas of $W(s,{\bf d}^m)$ and their
periods $\tau(G)$ for the irreducible Coxeter groups and a list for the first
ten symmetric group ${\cal S}_m$ are presented. A {\it least common multiple}
${\cal L}(m)$ of the series of the natural numbers 1,2,..,$m$ plays a role of
the period $\tau({\cal S}_m)$ of $W(s,{\bf d}^m)$ in ${\cal S}_m$. An
asymptotic behaviour of ${\cal L}(m)$ with $m \to \infty$ is found.

</DOC>
<DOC>
<DOCNO> 178501 </DOCNO>
Inelastic photon scattering and the magnetic moment of the $\Delta$


  The reaction $\gamma+p\to\gamma'+p+\pi^0$ has been suggested as a means to
deduce the $\Delta^+$ magnetic moment. The cross section for this process is
estimated in both the constituent quark model and an effective Lagrangian
procedure. The resulting total cross section is of the order 5-10 nb, which is
at the limit of present experimental capabilities.

</DOC>
<DOC>
<DOCNO> 119007 </DOCNO>
Mixing Metals in the Early Universe


  We investigate the evolution of the metallicity of the intergalactic medium
(IGM) with particular emphasis on its spatial distribution. We propose that
metal enrichment occurs as a two step process. First, supernova (SN) explosions
eject metals into relatively small regions confined to the surroundings of
star-forming galaxies. From a comprehensive treatment of blowout we show that
SNae by themselves fail by more than one order of magnitude to distribute the
products of stellar nucleosynthesis over volumes large enough to pollute the
whole IGM to the metallicity levels observed. Thus, a additional (but as yet
unknown) physical mechanism must be invoked to mix the metals on scales
comparable to the mean distance between the galaxies which are most efficient
pollutants. From this simple hypothesis we derive a number of testable
predictions for the evolution of the IGM metallicity. Specifically, we find
that: (i) the fraction of metals ejected over the star formation history of the
universe is about 50% at z=0; that is, approximately half of the metals today
are found in the IGM; (ii) if the ejected metals were homogeneously mixed with
the baryons in the universe, the average IGM metallicity would be <Z> ~ 1/25
Z(solar) at z=3. However, due to spatial inhomogeneities, the mean of the
distribution of metallicities in the diffusive zones has a wide (more than 2
orders of magnitude) spread around this value; (iii) if metals become more
uniformly distributed at z < 1, as assumed, at z = 0 the metallicity of the IGM
is narrowly confined within the range Z ~ 0.1 +/- 0.03 Z(solar). Finally, we
point out that our results can account for the observed metal content of the
intracluster medium.

</DOC>
<DOC>
<DOCNO> 121999 </DOCNO>
INT-WFS + 2dFGRS: The Local Space & Luminosity Density


  We discuss the quantification of the local galaxy population and the impact
of the ``New Era of Wide-Field Astronomy'' on this field, and, in particular,
systematic errors in the measurement of the Luminosity Function. New results
from the 2dFGRS are shown in which some of these selection effects have been
removed. We introduce an INT-WFS project which will further reduce the
selection biases. We show that there is a correlation between the surface
brightness and the luminosity of galaxies and that new technologies are having
a big impact on this field. Finally selection criteria from different surveys
are modelled and it is shown that some of the major selection effects are
surface brightness selection effects.

</DOC>
<DOC>
<DOCNO> 170734 </DOCNO>
Reducing the communication complexity with quantum entanglement


  We propose a probabilistic two-party communication complexity scenario with a
prior nonmaximally entangled state, which results in less communication than
that is required with only classical random correlations. A simple all-optical
implementation of this protocol is presented and demonstrates our conclusion.

</DOC>
<DOC>
<DOCNO> 68358 </DOCNO>
From Prototype SU(5) to Realistic SU(7) SUSY GUT


  We construct a realistic SU(7) model which provides answers to many questions
presently facing the prototype SU(5) SUSY GUT. Among them are a solution to the
doublet-triplet splitting problem, string scale unification, proton decay, the
hierarchy of baryon vs lepton number violation and neutrino masses.

</DOC>
<DOC>
<DOCNO> 119926 </DOCNO>
The evolution of type 1 AGN at 15um from the ELAIS


  We present the first preliminary estimate of the evolution of type 1 AGNs at
15 um. A new sample of sources selected from the ELAIS-S1 survey has been used
together with the RMS sample. The ELAIS-S1 survey covers an effective area of
2.2 deg^2 (total: 4 deg^2) down to 1.2 mJy at 15 um. Spectroscopic
identifications have been carried out in the range 17.2<R<20.0 at the 3.6m/ESO,
NTT/ESO and 2dF/AAT. The luminosity function is steeper at bright luminosities
in comparison to the previous estimates of Rush, Malkan & Spinoglio (1993). The
evolution is compatible with a Pure Luminosity Evolution model with
L(z)=L(0)(1+z)^3.4.

</DOC>
<DOC>
<DOCNO> 119678 </DOCNO>
The effects of numerical resolution on hydrodynamical surface convection


  The computationally demanding nature of radiative-hydrodynamical simulations
of stellar surface convection warrants an investigation of the sensitivity of
the convective structure and spectral synthesis to the numerical resolution and
dimension of the simulations, which is presented here. With too coarse a
resolution the predicted spectral lines tend to be too narrow, reflecting
insufficient Doppler broadening from the convective motions, while at the
currently highest affordable resolution the line shapes have converged
essentially perfectly to the observed profiles. Similar conclusions are drawn
from the line asymmetries and shifts. In terms of abundances, weak FeI and FeII
lines show a very small dependence (~0.02 dex) while for intermediate strong
lines with significant non-thermal broadening the sensitivity increases (~0.10
dex). Problems arise when using 2D convection simulations to describe an
inherent 3D phenomenon, which translates to inaccurate atmospheric velocity
fields and temperature and pressure structures. In 2D the theoretical line
profiles tend to be too shallow and broad compared with the 3D calculations and
observations, in particular for intermediate strong lines. In terms of
abundances, the 2D results are systematically about 0.1 dex lower than for the
3D case for FeI lines. Furthermore, the predicted line asymmetries and shifts
are much inferior in 2D. Given these shortcomings and computing time
considerations it is better to use 3D simulations of even modest resolution
than high-resolution 2D simulations.

</DOC>
<DOC>
<DOCNO> 80756 </DOCNO>
Overlap-Dirac fermions with a small hopping parameter


  We consider overlap-Dirac fermions at non-zero bare coupling and for a small
hopping parameter, or, equivalently, large $|M|$ with $M$ the domain-wall
height. We prove the existence of a phase at large positive $M$ where the
abelian axial group $U_A(1)$ is a symmetry, and the corresponding pseudo-scalar
is an exact Goldstone boson. We also provide a conjecture for the phase diagram
of asymptotically free gauge theories with overlap-Dirac fermions. In
particular, we suggest that, for large gauge coupling, the massive-fermion
phase at negative $M$ possibly extends to all $M<4$.

</DOC>
<DOC>
<DOCNO> 69977 </DOCNO>
On |V_{ub}| from the B -> X_u l \nu dilepton invariant mass spectrum


  The invariant mass spectrum of the lepton pair in inclusive semileptonic
$\bar B\to X_u \ell\bar\nu$ decay yields a model independent determination of
$|V_{ub}|$. Unlike the lepton energy and hadronic invariant mass spectra,
nonperturbative effects are only important in the resonance region, and play a
parametrically suppressed role when $d\Gamma / dq^2$ is integrated over $q^2 >
(m_B-m_D)^2$, which is required to eliminate the $\bar B\to X_c \ell\bar\nu$
background. We discuss these backgrounds for $q^2$ slightly below
$(m_B-m_D)^2$, and point out that instead of $q^2 > (m_B-m_D)^2 = 11.6 GeV^2$,
the cut can be lowered to $q^2 \gtrsim 10.5 GeV^2$. This is important
experimentally, particularly when effects of a finite neutrino reconstruction
resolution are included.

</DOC>
<DOC>
<DOCNO> 116517 </DOCNO>
Equivalence of Descriptions of Gravity In Both Curved and Flat


  It is proved in the manuscript that as long as the proper coordinate
transformation is introduced,, the equations of geodetic lines described in
curved space-time can be transformed into the dynamic equations in flat
space-time, that is to say, the Einstein theory of gravitation and other
theories based on the curved space-time can be identically transformed into
flat space-time to describe. As an example, the Schwarzschild solution of the
spherical symmetry gravitational field is transformed into flat space-time to
study. The results show that there exists no any singularity in the all
processes and the whole space-time including at the point r=0. So it seems more
rational to discuss the problems of gravitation in flat space-time.

</DOC>
<DOC>
<DOCNO> 10433 </DOCNO>
Motion of an object through a dilute quantum fluid


  We simulate the motion of a massive object through a dilute Bose-Einstein
condensate by numerical solution of the non-linear Schr\"odinger equation
coupled to an equation of motion for the object. Under a constant applied
force, the object accelerates up to a maximum velocity where a vortex ring is
formed which slows the object down. If the applied force is less than a
critical value, the object becomes trapped within the vortex core. We show that
the motion can be described using the time-independent quantum states, and use
these states to predict the conditions required for vortex scattering.

</DOC>
<DOC>
<DOCNO> 118488 </DOCNO>
MHD Models of Axisymmetric Protostellar Jets


  We present the results of a series of axisymmetric time-dependent
magnetohydrodynamic (MHD) simulations of the propagation of cooling, overdense
jets, motivated by the properties of outflows associated with young stellar
objects. A variety of initial field strengths and configurations are explored
for both steady and time-variable (pulsed) jets. Even apparently weak magnetic
fields with strengths B < 60 micro-G in the pre-shocked jet beam can have a
significant effect on the dynamics, for example by altering the density, width,
and fragmentation of thin shells formed by cooling gas. A linear analysis
predicts that axisymmetric pinch modes of the MHD Kelvin-Helmholtz instability
should grow only slowly for the highly supermagnetosonic jets studied here; we
find no evidence for them in our simulations. Some of our models appear
unstable to current-driven pinch modes, however the resulting pressure and
density variations induced in the jet beam are not large, making this mechanism
an unlikely source of emission knots in the jet beam. In the case of pulsed
jets, radial hoop stresses confine shocked jet material in the pulses to the
axis, resulting in a higher density in the pulses in comparison to purely
hydrodynamic models.

</DOC>
<DOC>
<DOCNO> 9542 </DOCNO>
First-order transitions and triple point on a random p-spin interaction


  The effects of competing quadrupolar- and spin-glass orderings are
investigated on a spin-1 Ising model with infinite-range random $p$-spin
interactions. The model is studied through the replica approach and a phase
diagram is obtained in the limit $p\to\infty$. The phase diagram, obtained
within replica-symmetry breaking, exhibits a very unusual feature in magnetic
models: three first-order transition lines meeting at a commom triple point,
where all phases of the model coexist.

</DOC>
<DOC>
<DOCNO> 118180 </DOCNO>
Reionization of the Universe and the Photoevaporation of Cosmological


  The first sources of ionizing radiation to condense out of the dark and
neutral IGM sent ionization fronts sweeping outward through their surroundings,
overtaking other condensed objects and photoevaporating them. This feedback
effect of universal reionization on cosmic structure formation is demonstrated
here for the case of a cosmological minihalo of dark matter and baryons exposed
to an external source of ionizing radiation with a quasar-like spectrum, just
after the passage of the global ionization front created by the source. We
model the pre-ionization minihalo as a truncated, nonsingular isothermal sphere
in hydrostatic equilibrium following its collapse out of the expanding
background universe and virialization. Results are presented of the first gas
dynamical simulations of this process, including radiative transfer. A sample
of observational diagnostics is also presented, including the spatially-varying
ionization levels of C, N, and O in the flow if a trace of heavy elements is
present and the integrated column densities of H I, He I and II, and C IV thru
the photoevaporating gas at different velocities which would be measured in
absorption against a background source like that responsible for the
ionization.

</DOC>
<DOC>
<DOCNO> 8954 </DOCNO>
First-principles calculations of the self-trapped exciton in crystalline


  The atomic and electronic structure of the lowest triplet state of the
off-center (C2v symmetry) self-trapped exciton (STE) in crystalline NaCl is
calculated using the local-spin-density (LSDA) approximation. In addition, the
Franck-Condon broadening of the luminescence peak and the a1g -> b3u absorption
peak are calculated and compared to experiment. LSDA accurately predicts
transition energies if the initial and final states are both localized or
delocalized, but 1 eV discrepancies with experiment occur if one state is
localized and the other is delocalized.

</DOC>
<DOC>
<DOCNO> 71766 </DOCNO>
Constraints on color dipole-nucleon cross section from diffractive heavy


  We study the hard color dipole-nucleon cross section within perturbative QCD
and discuss its relation to observables in diffractive leptoproduction of heavy
quarkonium. The dipole cross section calculated with the unintegrated gluon
density of the nucleon substantially differs from the well-known perturbative
form $\sigma_{dip} \sim b^2$ for $b > 0.3$fm, where $b$ is the transverse
separation of the dipole. We show the measured ratio of $\psi '$ to $J / \psi$
photoproduction cross sections constrains the dipole cross section at
intermediate $b$, and in fact excludes the simple $\sigma_{dip} \sim b^2$
behavior. We also calculate the $t$-slopes of the diffractive $J / \psi, \psi
'$ productions. We emphasize the difference of $t$-slopes, $B_{J/\psi} -
B_{\psi '}$, is dominated by the dipole-nucleon dynamics. This difference is
found to be about $0.3 {GeV}^{-2}$ with our dipole cross section.

</DOC>
<DOC>
<DOCNO> 100508 </DOCNO>
On the Leibniz cohomology of vector fields


  I. M. Gelfand and D. B. Fuks have studied the cohomology of the Lie algebra
of vector fields on a manifold. In this article, we generalize their main tools
to compute the Leibniz cohomology, by extending the two spectral sequences
associated to the diagonal and the order filtration. In particular, we
determine some new generators for the diagonal Leibniz cohomology of the Lie
algebra of vector fields on the circle.

</DOC>
<DOC>
<DOCNO> 68946 </DOCNO>
Algebraic Models of Hadron Structure II. Strange Baryons


  The algebraic treatment of baryons is extended to strange resonances. Within
this framework we study a collective string-like model in which the radial
excitations are interpreted as rotations and vibrations of the strings. We
derive a mass formula and closed expressions for strong and electromagnetic
decay widths and use these to analyze the available experimental data.

</DOC>
<DOC>
<DOCNO> 80767 </DOCNO>
Residual Chiral Symmetry Breaking in Domain-Wall Fermions


  We study the effective quark mass induced by the finite separation of the
domain walls in the domain-wall formulation of chiral fermion as the function
of the size of the fifth dimension ($L_s$), the gauge coupling $\beta$ and the
physical volume $V$. We measure the mass by calculating the small eigenvalues
of the hermitian domain-wall Dirac operator ($H_{\rm DWF}(m_0))$ in the
topologically-nontrivial quenched SU(3) gauge configurations. We find that the
induced quark mass is nearly independent of the physical volume, decays
exponentially as a function of $L_s$, and has a strong dependence on the size
of quantum fluctuations controlled by $\beta$. The effect of the choice of the
lattice gluon action is also studied.

</DOC>
<DOC>
<DOCNO> 84711 </DOCNO>
Power, energy, and spectrum of a naked singularity explosion


  Naked singularity occurs in the gravitational collapse of an inhomogeneous
dust ball from an initial density profile which is physically reasonable. We
show that explosive radiation is emitted during the formation process of the
naked singularity. The energy flux is proportional to $(t_{\rm CH}-t)^{-3/2}$
for a minimally coupled massless scalar field, while is proportional to
$(t_{\rm CH}-t)^{-1}$ for a conformally coupled massless scalar field, where
$t_{\rm CH}-t$ is the `remained time' until the distant observer could observe
the singularity if the naked singularity was formed. As a consequence, the
radiated energy grows unboundedly for both scalar fields. The amount of the
power and the energy depends on parameters which characterize the initial
density profile but do not depend on the gravitational mass of the cloud. In
particular, there is characteristic frequency $\nu_{s}$ of singularity above
which the divergent energy is radiated. The energy flux is dominated by
particles of which the wave length is about $t_{\rm CH}-t$ at each moment. The
observed total spectrum is nonthermal, i.e., $\nu dN/d\nu \sim
(\nu/\nu_{s})^{-1}$ for $\nu>\nu_{s}$. If the naked singularity formation could
continue until a considerable fraction of the total energy of the dust cloud is
radiated, the radiated energy would reach about $10^{54}(M/M_{\odot})$ erg. The
calculations are based on the geometrical optics approximation which turns out
to be consistent as a rough order estimate. The analysis does not depend on
whether or not the naked singularity occurs in its exact meaning. This
phenomenon may provide a new candidate for a source of ultra high energy cosmic
rays or a central engine of gamma ray bursts.

</DOC>
<DOC>
<DOCNO> 120239 </DOCNO>
Substellar Companions to Nearby Stars from NICMOS Surveys


  A coronagraphic imaging survey of 65 nearby stars was conducted using the
Near Infrared Camera and Multi-Object Spectrometer (NICMOS) on the Hubble Space
Telescope by the Instrument Definition Team. Using these guaranteed time
observations we searched for very low mass stellar and substellar (extra-solar
giant planet and brown dwarf) companions to young main sequence and late M
dwarf stars. Nineteen additional stars, similarly observed in our circumstellar
disk program, were also examined for evidence of companions. We discuss the
large depth and dynamic range of these surveys which have given rise to several
putative and confirmed detections. Using follow-up spectrographic observations
obtained with the Space Telescope Imaging Spectrograph (STIS) we have begun to
characterize the physical nature of the objects found in the companion search
program.

</DOC>
<DOC>
<DOCNO> 9514 </DOCNO>
Exactly Solvable Ginzburg-Landau theories of Superconducting Order


  We consider two families of exactly solvable models describing thermal
fluctuations in two-dimensional superconductors coupled to phonons living in an
insulating layer, and study the stability of the superconducting state with
respect to vortices. The two families are characterized by one or two
superconducting planes. The results suggest that the effective critical
temperature increases with the thickness of the insulating layer. Also the
presence of the additional superconducting layer has the same effect.

</DOC>
<DOC>
<DOCNO> 10572 </DOCNO>
Shot noise at hopping via two sites


  The average current and the shot noise at correlated sequential tunneling via
two localized sites are studied. At zero temperature the Fano factor averaged
over the positions and energies of sites is shown to be 0.707. The noise
dependence on temperature and frequency is analyzed numerically.

</DOC>
<DOC>
<DOCNO> 101941 </DOCNO>
Wulff construction in statistical mechanics and in combinatorics


  We present the geometric solutions to some variational problems of
statistical mechanics and combinatorics. Together with the Wulff construction,
which predicts the shape of the crystals, we discuss the construction which
exhibits the shape of a typical Young diagram and of a typical skyscraper.

</DOC>
<DOC>
<DOCNO> 178413 </DOCNO>
Adiabatic Selfconsistent Collective Coordinate Method for Large


  An adiabatic approximation to the selfconsistent collective coordinate method
is formulated in order to describe large amplitude collective motions in
superconducting nuclei on the basis of the time-dependent
Hartree-Fock-Bogoliubov equations of motion. The basic equations are presented
in a local harmonic form which can be solved in a similar way as the
quasiparticle RPA equations. The formalism guarantees the conservation of
nucleon number expectation values. An extension to the multi-dimensional case
is also discussed.

</DOC>
<DOC>
<DOCNO> 117145 </DOCNO>
Vortex tubes in velocity fields of laboratory isotropic turbulence


  The streamwise and transverse velocities are measured simultaneously in grid
turbulence at Reynolds numbers 100-300. We extract typical intermittency
patterns, which are consistent with velocity profiles of Burgers and Lamb-Oseen
vortices. The radii of these vortex tubes are estimated to be several of the
Kolmogorov length.

</DOC>
<DOC>
<DOCNO> 122100 </DOCNO>
Accretion column eclipses in the X-ray pulsars GX 1+4 and RX


  Sharp dips observed in the pulse profiles of three X-ray pulsars (GX 1+4, RX
J0812.4-3114 and A 0535+26) have previously been suggested to arise from
partial eclipses of the emission region by the accretion column occurring once
each rotation period. We present pulse-phase spectroscopy from Rossi X-ray
Timing Explorer satellite observations of GX 1+4 and RX J0812.4-3114 which for
the first time confirms this interpretation. The dip phase corresponds to the
closest approach of the column axis to the line of sight, and the additional
optical depth for photons escaping from the column in this direction gives rise
to both the decrease in flux and increase in the fitted optical depth measured
at this phase. Analysis of the arrival time of individual dips in GX~1+4
provides the first measurement of azimuthal wandering of a neutron star
accretion column. The column longitude varies stochastically with standard
deviation 2-6 degrees depending on the source luminosity. Measurements of the
phase width of the dip both from mean pulse profiles and individual eclipses
demonstrates that the dip width is proportional to the flux. The variation is
consistent with that expected if the azimuthal extent of the accretion column
depends only upon the Keplerian velocity at the inner disc radius, which varies
as a consequence of the accretion rate Mdot.

</DOC>
<DOC>
<DOCNO> 99718 </DOCNO>
Geometry without Topology


  The proper Euclidean geometry is considered to be metric space and described
in terms of only metric and finite metric subspaces (sigma-immanent
description). Constructing the geometry, one does not use topology and
topological properties. For instance, the straight, passing through points A
and B, is defined as a set of such points R that the area S(A,B,R) of the
triangle ABR vanishes. The triangle area is expressed via metric by means of
the Hero's formula, and the straight appears to be defined only via metric,
i.e. without a reference to (topological) concept of curve. (Usually the
straight is defined as the shortest curve, connecting two points A and B). Such
a construction of geometry is free from constraints (continuity, dimensionality
of space), generated by a use of topology, but not by geometry in itself. At
such a description all information on the geometry properties (such as
uniformity, isotropy, continuity and degeneracy) is contained in metric.
Modifying the metric, one changes the geometry automatically. The Riemannian
geometry is constructed by two different ways: (1) by conventional way on the
basis of metric tensor, (2) as a result of modification of the metric in the
sigma-immanent description of the proper Euclidean geometry. The two obtained
geometries are compared. The convexity problem in geometry and the problem of
collinerity of vectors at distant points are considered. The nonmetric
definition of curve is shown to be a concept of only proper Euclidean geometry.
It is inadequate to any non-Euclidean geometry.

</DOC>
<DOC>
<DOCNO> 102222 </DOCNO>
Tangential Structures on Toric Manifolds, and Connected Sums of


  We extend work of Davis and Januszkiewicz by considering {\it omnioriented}
toric manifolds, whose canonical codimension-2 submanifolds are independently
oriented. We show that each omniorientation induces a canonical stably complex
structure, which is respected by the torus action and so defines an element of
an equivariant cobordism ring. As an application, we compute the complex
bordism groups and cobordism ring of an arbitrary omnioriented toric manifold.
We consider a family of examples $B_{i,j}$, which are toric manifolds over
products of simplices, and verify that their natural stably complex structure
is induced by an omniorientation. Studying connected sums of products of the
$B_{i,j}$ allows us to deduce that every complex cobordism class of dimension
>2 contains a toric manifold, necessarily connected, and so provides a positive
answer to the toric analogue of Hirzebruch's famous question for algebraic
varieties. In previous work, we dealt only with disjoint unions, and ignored
the relationship between the stably complex structure and the action of the
torus. In passing, we introduce a notion of connected sum $#$ for simple
$n$-dimensional polytopes; when $P^n$ is a product of simplices, we describe
$P^n# Q^n$ by applying an appropriate sequence of {\it pruning operators}, or
hyperplane cuts, to $Q^n$.

</DOC>
<DOC>
<DOCNO> 122822 </DOCNO>
The Genesis of Super Star Clusters as Self-Gravitating HII Regions


  We examine the effects of ionization, radiation pressure and main sequence
winds from massive stars on self-gravitating, clumpy molecular clouds, thereby
modeling the formation and pre-supernova feedback of massive star clusters. We
find the process of ``turbulent mass loading'' is effective in confining HII
regions. Extrapolating typical Galactic high-mass star forming regions to
greater initial gas cloud masses and assuming steady star formation rates, we
determine the timescales for cloud disruption. We find that a dense n_c ~ 2 x
10^5 cm^-3 cloud with initial mass M_c ~ 4 x 10^5 M_sun is able to form ~2 x
10^5 M_sun of stars (50% efficiency) before feedback disperses the gas after ~3
Myr. This mass and age are typical of young, optically visible super star
clusters (SSCs). The high efficiency permits the creation of a bound stellar
system.

</DOC>
<DOC>
<DOCNO> 178481 </DOCNO>
Three-Body-Cluster Effects on Lambda Single-Particle Energies in


  A method for a microscopic description of Lambda hypernuclei is formulated in
the framework of the unitary-model-operator approach. A unitarily transformed
hamiltonian is introduced and given in a cluster expansion form. The structure
of three-body-cluster terms are discussed especially on the Lambda
single-particle energy. The Lambda single-particle energies including the
three-body-cluster contributions are calculated for the 0s_{1/2}, 0p_{3/2} and
0p_{1/2} states in_{Lambda}^{17}O, and for the 0s_{1/2}, 0p_{3/2}, 0p_{1/2},
0d_{5/2}, 0d_{3/2} and 1s_{1/2} states in_{Lambda}^{41}Ca, using the Nijmegen
soft-core (NSC), NSC97a-f, the Juelich A (J A) and J B hyperon-nucleon
interactions. It is indicated that the three-body-cluster terms bring about
sizable effects in the magnitudes of the Lambda single-particle energies, but
hardly affect the Lambda spin-orbit splittings.

</DOC>
<DOC>
<DOCNO> 99988 </DOCNO>
The solution to a conjecture of Tits on the subgroup generated by the


  It was conjectured by Tits that the only relations amongst the squares of the
standard generators of an Artin group are the obvious ones, namely that a^2 and
b^2 commute if ab=ba appears as one of the Artin relations. In this paper we
prove Tits' conjecture for all Artin groups. More generally, we show that,
given a number m(s)>1 for each Artin generator s, the only relations amongst
the powers s^m(s) of the generators are that a^m(a) and b^m(b) commute if ab=ba
appears amongst the Artin relations.

</DOC>
<DOC>
<DOCNO> 151669 </DOCNO>
Maxwell Chern Simons Theory in a Geometric Representation


  We quantize the Maxwell Chern Simons theory in a geometric representation
that generalizes the Abelian Loop Representation of Maxwell theory. We find
that in the physical sector, the model can be seen as the theory of a massles
scalar field with a topological interaction that enforces the wave functional
to be multivalued. This feature allows to relate the Maxwell Chern Simons
theory with the quantum mechanics of particles interacting through a Chern
Simons field

</DOC>
<DOC>
<DOCNO> 69937 </DOCNO>
Equation of state of cosmic strings with fermionic current-carriers


  The relevant characteristic features, including energy per unit length and
tension, of a cosmic string carrying massless fermionic currents in the
framework of the Witten model in the neutral limit are derived through
quantization of the spinor fields along the string. The construction of a Fock
space is performed by means of a separation between longitudinal modes and the
so-called transverse zero energy solutions of the Dirac equation in the vortex.
As a result, quantization leads to a set of naturally defined state parameters
which are the number densities of particles and anti-particles trapped in the
cosmic string. It is seen that the usual one-parameter formalism for describing
the macroscopic dynamics of current-carrying vortices is not sufficient in the
case of fermionic carriers.

</DOC>
<DOC>
<DOCNO> 11328 </DOCNO>
Indications of Spin-Charge Separation at Short Distance and Stripe


  The recently discussed tendency of holes to generate nontrivial spin
environments in the extended two-dimensional t-J model (G. Martins, R. Eder,
and E. Dagotto, Phys. Rev. B{\bf 60}, R3716 (1999)) is here investigated using
computational techniques applied to ladders with several number of legs. This
tendency is studied also with the help of analytic spin-polaron approaches
directly in two dimensions. Our main result is that the presence of robust
antiferromagnetic correlations between spins located at both sides of a hole
either along the x or y axis, observed before numerically on square clusters,
is also found using ladders, as well as applying techniques based on a
string-basis expansion. This so-called ``across-the-hole'' nontrivial structure
exists even in the two-leg spin-gapped ladder system, and leads to an effective
reduction in dimensionality and spin-charge separation at short-distances, with
a concomitant drastic reduction in the quasiparticle (QP) weight Z. In general,
it appears that holes tend to induce one-dimensional-like spin arrangements to
improve their mobility. Using ladders it is also shown that the very small
J/t$\sim$0.1 regime of the standard t-J model may be more realistic than
anticipated in previous investigations, since such regime shares several
properties with those found in the extended model at realistic couplings.
Another goal of the present article is to provide additional information on the
recently discussed tendencies to stripe formation and spin incommensurability
reported for the extended t-J model.

</DOC>
<DOC>
<DOCNO> 80807 </DOCNO>
Renormalization-group Calculation of Color-Coulomb Potential


  We report here on the application of the perturbative renormalization-group
to the Coulomb gauge in QCD. We use it to determine the high-momentum
asymptotic form of the instantaneous color-Coulomb potential $V(\vec{k})$ and
of the vacuum polarization $P(\vec{k}, k_4)$. These quantities are
renormalization-group invariants, in the sense that they are independent of the
renormalization scheme. A scheme-independent definition of the running coupling
constant is provided by $\vec{k}^2 V(\vec{k}) = x_0
g^2(\vec{k}/\Lambda_{coul})$, and of $\alpha_s \equiv {{g^2(\vec{k} /
\Lambda_{coul})} \over {4\pi}}$, where $x_0 = {{12N} \over {11N - 2N_f}}$, and
$\Lambda_{coul}$ is a finite QCD mass scale. We also show how to calculate the
coefficients in the expansion of the invariant $\beta$-function $\beta(g)
\equiv |\vec{k}| {{\partial g} \over{\partial |\vec{k}|}} = -(b_0 g^3 + b_1 g^5
+b_2 g^7 + ...)$, where all coefficients are scheme-independent.

</DOC>
<DOC>
<DOCNO> 120884 </DOCNO>
Cosmic Statistics of Statistics: N-point Correlations


  The fully general calculation of the cosmic error on N-point correlation
functions and related quantities is presented. More precisely, the variance
caused by the finite volume, discreteness, and edge effects is determined for
{\em any} estimator which is based on a general function of N-tuples, such as
multi-point correlation functions and multi-spectra. The results are printed
explicitly for the two-point correlation function (or power-spectrum), and for
the three-point correlation (or bispectrum). These are the most popular
statistics in the study of large scale structure, yet, the a general
calculation of their variance has not been performed until now.

</DOC>
<DOC>
<DOCNO> 70681 </DOCNO>
Hard Parton Rescatterings and Minijets in Nuclear Collisions at LHC


  The average number of minijets and the corresponding transverse energy
produced in heavy ion collisions are evaluated by including explicitly
semi-hard parton rescatterings in the dynamics of the interaction. At the LHC
semi-hard rescatterings have a sizable effect on global characteristics of the
typical inelastic event. An interesting feature is that the dependence on the
cutoff which separates soft and hard parton interactions becomes less critical
after taking rescatterings into account.

</DOC>
<DOC>
<DOCNO> 40384 </DOCNO>
Perturbative contribution to the sin(phi) asymmetry in inclusive pi^{+}


  We consider the sin(phi) single target-spin asymmetry in deep-inelastic
pi^{+} inclusive electroproduction off a longitudinally polarized target. We
show that at larger transverse momentum of the outgoing hadron the evaluated
asymmetry decreases if one takes into account the first order alpha_S
perturbative contribution to the cross section, integrated over the azimuthal
angle. This leads to good agreement with recent HERMES data.

</DOC>
<DOC>
<DOCNO> 68802 </DOCNO>
Proton Decay in the Supersymmetric Grand Unified Models


  In this article we review proton decay in the supersymmetric grand unified
models.

</DOC>
<DOC>
<DOCNO> 83285 </DOCNO>
A Numerical Study of the Performance of a Quantum Adiabatic Evolution


  Quantum computation by adiabatic evolution, as described in quant-ph/0001106,
will solve satisfiability problems if the running time is long enough. In
certain special cases (that are classically easy) we know that the quantum
algorithm requires a running time that grows as a polynomial in the number of
bits. In this paper we present numerical results on randomly generated
instances of an NP-complete problem and of a problem that can be solved
classically in polynomial time. We simulate a quantum computer (of up to 16
qubits) by integrating the Schrodinger equation on a conventional computer. For
both problems considered, for the set of instances studied, the required
running time appears to grow slowly as a function of the number of bits.

</DOC>
<DOC>
<DOCNO> 40173 </DOCNO>
The strong coupling and the gluon density from jets in DIS


  The extraction of the parameters of perturbative QCD is one of the main tasks
for the HERA experiments. Studies on the structure of the hadronic final states
with jet algorithms give a direct handle on the parton density functions and
the strong coupling strength over a wide kinematic range. In this article, new
results of the H1 and ZEUS collaborations for the strong coupling and the gluon
density in the proton are presented.

</DOC>
<DOC>
<DOCNO> 71389 </DOCNO>
Classical Yang-Mills Vacua on $T^{3}$ : Explicit Constructions


  Flat connections for unitary gauge groups on a 3--torus with twisted boundary
conditions as well as recently discovered periodic nontrivial flat connections
with ``nondiagonalizable'' triples of holonomies for higher orthogonal and
exceptional groups are constructed explicitly in terms of Jacobi theta
functions with rational characteristics. The (fractional) Chern-Simons numbers
of these vacuum gauge field configurations are verified by direct computation.

</DOC>
<DOC>
<DOCNO> 12188 </DOCNO>
Statistically Significant Strings are Related to Regulatory Elements in


  Finding out statistically significant words in DNA and protein sequences
forms the basis for many genetic studies. By applying the maximal entropy
principle, we give one systematic way to study the nonrandom occurrence of
words in DNA or protein sequences. Through comparison with experimental
results, it was shown that patterns of regulatory binding sites in
Saccharomyces cerevisiae(yeast) genomes tend to occur significantly in the
promoter regions. We studied two correlated gene family of yeast. The method
successfully extracts the binding sites varified by experiments in each family.
Many putative regulatory sites in the upstream regions are proposed. The study
also suggested that some regulatory sites are a ctive in both directions, while
others show directional preference.

</DOC>
<DOC>
<DOCNO> 102765 </DOCNO>
Invitation to higher local fields (Introduction)


  The monograph "Invitation to higher local fields" is the result of the
conference on higher local fields held in Muenster, August 29 to September 5,
1999. The aim is to provide an introduction to higher local fields (more
generally complete discrete valuation fields with arbitrary residue field) and
render the main ideas of this theory (Part I), as well as to discuss several
applications and connections to other areas (Part II).
  The volume grew as an extended version of talks given at the conference. The
two parts are separated by a paper of K. Kato, an IHES preprint from 1980 which
has never been published.
  We hope that the volume will be a useful introduction and guide to the
subject. The contributions to this volume were received over the period
November 1999 to August 2000 and the electronic publication date is 10 December
2000. This is the introduction: math.NT/0012131.
  Other arXiv references are as follows:
  Part I: Sections 1: math.NT/0012132, 2:math.NT/0012133, A:math.NT/0012134,
4:math.NT/0012135, 5:math.NT/0012136, 6:math.NT/0012137, 7:math.NT/0012138,
8:math.NT/0012139, 9:math.NT/0012140, 10:math.NT/0012141, 11:math.NT/0012142,
12:math.NT/0012143, 13:math.NT/0012144, 14:math.NT/0012145, 15:math.NT/0012146,
16:math.NT/0012147, 17:math.NT/0012148, 18:math.NT/0012149 .
  Interlude: math.NT/0012150 .
  Part II: Sections 1:math.NT/0012151, 2:math.NT/0012152, 3:math.NT/0012153,
4:math.NT/0012154, 5:math.NT/0012155, 6:math.NT/0012156, 7:math.NT/0012157,
8:math.NT/0012158, 9:math.NT/0012159, 10:math.NT/0012160 .

</DOC>
<DOC>
<DOCNO> 123067 </DOCNO>
Effect of Magnetic Field on the Phase Transition from Nuclear Matter to


  We have studied phase transition from hadron matter to quark matter in the
presence of high magnetic fields incorporating the trapped electron neutrinos
at finite temperatures. We have used the density dependent quark mass (DDQM)
model for the quark phase while the hadron phase is treated in the frame-work
of relativistic mean field theory. It is seen that the nuclear energy at phase
transition decreases with both magnetic field and temperature. A brief
discussion of the effect of magnetic field in supernova explosions and
proto-neutron star evolution is given.

</DOC>
<DOC>
<DOCNO> 9243 </DOCNO>
Concept of local polaritons and optical properties of mixed polar


  The concept of local polaritons is used to describe optical properties of
mixed crystals in the frequency region of their {\it restrahlen} band. It is
shown that this concept allows for a physically transparent explanation of the
presence of weak features in the spectra of so called one-mode crystals, and
for one-two mode behavior. The previous models were able to explain these
features only with the use of many fitting parameters. We show that under
certain conditions new impurity-induced polariton modes may arise within the
{\it restrahlen} of the host crystals, and study their dispersion laws and
density of states. Particularly, we find that the group velocity of these
excitations is proportional to the concentration of the impurities and can be
thousands of times smaller then the speed of light in vacuum.

</DOC>
<DOC>
<DOCNO> 10846 </DOCNO>
Quantum Chaos & Quantum Computers


  The standard generic quantum computer model is studied analytically and
numerically and the border for emergence of quantum chaos, induced by
imperfections and residual inter-qubit couplings, is determined. This
phenomenon appears in an isolated quantum computer without any external
decoherence. The onset of quantum chaos leads to quantum computer hardware
melting, strong quantum entropy growth and destruction of computer operability.
The time scales for development of quantum chaos and ergodicity are determined.
In spite the fact that this phenomenon is rather dangerous for quantum
computing it is shown that the quantum chaos border for inter-qubit coupling is
exponentially larger than the energy level spacing between quantum computer
eigenstates and drops only linearly with the number of qubits n. As a result
the ideal multi-qubit structure of the computer remains rather robust against
imperfections. This opens a broad parameter region for a possible realization
of quantum computer. The obtained results are related to the recent studies of
quantum chaos in such many-body systems as nuclei, complex atoms and molecules,
finite Fermi systems and quantum spin glass shards which are also reviewed in
the paper.

</DOC>
<DOC>
<DOCNO> 102600 </DOCNO>
2-Cocycles on the Lie algebras of generalized differential operators


  In a recent paper by Zhao and the author, the Lie algebras $A[D]=A\otimes
F[D]$ of Weyl type were defined and studied, where $A$ is a commutative
associative algebra with an identity element over a field $F$ of any
characteristic, and $F[D]$ is the polynomial algebra of a commutative
derivation subalgebra $D$ of $A$. In the present paper, the 2-cocycles of a
class of the above Lie algebras $A[D]$ (which are called the Lie algebras of
generalized differential operators in the present paper), with $F$ being a
field of characteristic 0, are determined. Among all the 2-cocycles, there is a
special one which seems interesting. Using this 2-cocycle, the central
extension of the Lie algebra is defined.

</DOC>
<DOC>
<DOCNO> 12070 </DOCNO>
Kondo and mixed valence regimes in multi-level quantum dots


  We investigate the dependence of the ground state of a multi-level quantum
dot on the coupling to an external fermionic system and on the interactions in
the dot. As the coupling to the external system increases, the rearrangement of
the effective energy levels in the dot signals the transition from the Kondo
regime to a mixed valence (MV) regime. The MV regime in a two level dot is
characterized by an intrinsic mixing of the levels in the dot, resulting in
non-perturbative sub- and super-tunneling phenomena that strongly influence the
Kondo effect.

</DOC>
<DOC>
<DOCNO> 9197 </DOCNO>
Electrical conductance of a 2D packing of metallic beads under thermal


  Electrical conductivity measurements on a 2D packing of metallic beads have
been performed to study internal rearrangements in weakly pertubed granular
materials. Small thermal perturbations lead to large non gaussian conductance
fluctuations. These fluctuations are found to be intermittent and gathered in
bursts. The distributions of the waiting time between to peaks is found to be a
power law inside bursts. The exponent is independent of the bead network, the
intensity of the perturbation and external stress. these bursts are interpreted
as the signature of individual bead creep rather than collective vaults
reorganisations. We propose a simple model linking the exponent of the waiting
time distribution to the roughness exponent of the surface of the beads.

</DOC>
<DOC>
<DOCNO> 170681 </DOCNO>
Maximally entangled mixed states of two qubits


  We consider mixed states of two qubits and show under which global unitary
operations their entanglement is maximized. This leads to a class of states
that is a generalization of the Bell states. Three measures of entanglement are
considered: entanglement of formation, negativity and relative entropy of
entanglement. Surprisingly all states that maximize one measure also maximize
the others. We will give a complete characterization of these generalized Bell
states and prove that these states for fixed eigenvalues are all equivalent
under local unitary transformations. We will furthermore characterize all
nearly entangled states closest to the maximally mixed state and derive a new
lower bound on the volume of separable mixed states.

</DOC>
<DOC>
<DOCNO> 12606 </DOCNO>
Dynamical Phases of Driven Vortices Interacting with Periodic Pinning


  The finite temperature dynamical phases of vortices in films driven by a
uniform force and interacting with the periodic pinning potential of a square
lattice of columnar defects are investigated by Langevin dynamics simulations
of a London model. Vortices driven along the [0,1] direction and at densities
for which there are more vortices than columnar defects ($B>B_{\phi}$) are
considered. At low temperatures, two new dynamical phases, elastic flow and
plastic flow, and a sharp transition between them are identified and
characterized according to the behavior of the vortex spatial order, velocity
distribution and frequency-dependent velocity correlation

</DOC>
<DOC>
<DOCNO> 84324 </DOCNO>
Initial Conditions and the Structure of the Singularity in Pre-Big-Bang


  We propose a picture, within the pre-big-bang approach, in which the universe
emerges from a bath of plane gravitational and dilatonic waves. The waves
interact gravitationally breaking the exact plane symmetry and lead generically
to gravitational collapse resulting in a singularity with the Kasner-like
structure. The analytic relations between the Kasner exponents and the initial
data are explicitly evaluated and it is shown that pre-big-bang inflation may
occur within a dense set of initial data. Finally, we argue that plane waves
carry zero gravitational entropy and thus are, from a thermodynamical point of
view, good candidates for the universe to emerge from.

</DOC>
<DOC>
<DOCNO> 102500 </DOCNO>
On the constants in some inequalities for the Sobolev norms and


  We consider the Sobolev norms of the pointwise product of two functions, and
estimate from above and below the constants appearing in two related
inequalities.

</DOC>
<DOC>
<DOCNO> 99955 </DOCNO>
Compact singularities of meromorphic mappings between complex


  We prove that a meromorphic map defined on the complement of a compact subset
of a three-dimensional Stein manifold M and with values in a compact complex
three-fold X extends to the complement of a finite set of points. If X is
simply connected, then the map extends to all of M.

</DOC>
<DOC>
<DOCNO> 116738 </DOCNO>
The GPS global detection of the ionospheric response to solar flares


  This author suggests the concept of a new technology for global detection
(GLOBDET) of atmospheric disturbances of natural and technogenic origin, on the
basis of phase measurements of the total electron content (TEC) in the
ionosphere using an international GPS network. Temporal dependencies of TEC are
obtained for a set of spaced receivers of the GPS network simultaneously for
the entire set of "visible" (over a given time interval) GPS satellites (up to
5-10 satellites). These series are subjected to filtering in the selected range
of oscillation periods using algorithms for spatio-temporal analysis of signals
of non-equidistant GPS phased antenna arrays which are adequate to the detected
disturbance. An analysis is made of the possibilities of using the GLOBDET when
detecting the ionospheric response of solar flares. In this case it is best to
make the coherent summation of the filtered series of TEC. A powerful impulsive
flares of July 29, 1999 and December 28, 1999 were chosen to illustrate the
practical implementation of the proposed method.

</DOC>
<DOC>
<DOCNO> 7619 </DOCNO>
Persistence of Vibrational Modes in a Classical Two-Dimensional Electron


  Vibrational density of states of a classical two-dimensional electron system
obtained with a molecular-dynamics simulation is shown to have a peak in both
solid and liquid phases. From an exact diagonalisation of the dynamical matrix,
the peak is identified to be vibrational modes having wavelengths of the order
of the electron spacing, and the result is interpreted as persistent
vibrational modes with short wavelengths in a liquid.

</DOC>
<DOC>
<DOCNO> 100648 </DOCNO>
Self-dual Codes over the Kleinian Four Group


  We introduce self-dual codes over the Kleinian four group K = Z_2 x Z_2 for a
natural quadratic form on K^n and develop the theory.
  Topics studied are: weight enumerators, mass formulas, classification up to
length 8, neighbourhood graphs, extremal codes, shadows, generalized t-designs,
lexicographic codes, the Hexacode and its odd and shorter cousin, automorphism
groups, marked codes.
  Kleinian codes form a new and natural fourth step in a series of analogies
between binary codes, lattices and vertex operator algebras. This analogy will
be emphasized and explained in detail.

</DOC>
<DOC>
<DOCNO> 12804 </DOCNO>
Oscillator Strength of Metallic Carbon Nanotubes


  Based on the tight binding method with hopping integral between the
nearest-neighbor atoms, an oscillator strength $\int_0^{\infty} \d \omega {\rm
Re} \sigma (\omega)$ is discussed for armchair and metallic zigzag carbon
nanotubes. The formulae of the oscillator strength are derived for both types
of nanotubes and are compared with the result obtained by a linear chain model.
In addition, the doping dependence is investigated in the absence of Coulomb
interaction. It is shown that the oscillator strength of each carbon nanotube
shows qualitatively the same doping dependence, but the fine structure is
different due to it's own peculiar band structure. Some relations independent
of the radius of the tube are derived, and a useful formula for determining the
amount of doping is proposed.

</DOC>
<DOC>
<DOCNO> 99304 </DOCNO>
Special Lagrangian Geometry in irreducible symplectic 4-folds


  Having fixed a Kaehler class and the unique corresponding hyperkaehler
metric, we prove that all special Lagrangian submanifolds of an irreducible
symplectic 4-fold X are bi-Lagrangian and that they are obtained by complex
submanifolds via a sort of "hyperkaehler rotation trick"; thus they retain part
of the rigidity of complex submanifolds: indeed all special Lagrangian
submanifolds of X turn out to be real analytic.

</DOC>
<DOC>
<DOCNO> 123116 </DOCNO>
UHECR Production by a Compact Black-Hole Dynamo: Application to Sgr A*


  The possibility that the excess cosmic ray (CR) flux near 10$^{18}$ eV,
reported recently by the AGASA group, is due to a compact black hole dynamo
associated with the Sgr A* source is considered. Under the assumption that the
Galactic center black hole rotates with nearly maximal spin, and that the
magnetic field threading the horizon is in rough equipartition with matter
accreted by the hole, the spectra and total fluxes of accelerated CRs and their
associated curvature emission depend only on accretion rate. For the accretion
rate estimated on the basis of observations of stellar winds near Sgr A* ($\sim
10^{-3}$ Eddington), the maximum proton energy achievable by this mechanism is
of the order of $10^{18}$ eV, and the corresponding CR power is $\sim
10^{41}\alpha_{CR}$ erg s$^{-1}$, where $\alpha_{CR}<<1$ is the CR production
efficiency. The corresponding spectrum of curvature photons peaks at around a
hundred GeV, with a total luminosity comparable to the CR power released. For
much lower accretion rates both the CR and gamma-ray fluxes predicted are
completely insignificant. Upcoming gamma-ray experiments, such as CANGAROO,
HESS and GLAST, can be used to probe the parameters of this system.

</DOC>
<DOC>
<DOCNO> 39953 </DOCNO>
CsI(Tl) for WIMP dark matter searches


  We report a study of CsI(Tl) scintillator to assess its applicability in
experiments to search for dark matter particles. Measurements of the mean
scintillation pulse shapes due to nuclear and electron recoils have been
performed. We find that, as with NaI(Tl), pulse shape analysis can be used to
discriminate between electron and nuclear recoils down to 4 keV. However, the
discrimination factor is typically (10-15)% better than in NaI(Tl) above 4 keV.
The quenching factor for caesium and iodine recoils was measured and found to
increase from 11% to ~17% with decreasing recoil energy from 60 to 12 keV.
Based on these results, the potential sensitivity of CsI(Tl) to dark matter
particles in the form of neutralinos was calculated. We find an improvement
over NaI(Tl) for the spin independent WIMP-nucleon interactions up to a factor
of 5 assuming comparable electron background levels in the two scintillators.

</DOC>
<DOC>
<DOCNO> 117751 </DOCNO>
RR Lyrae - Theory vs Observation


  The luminosities, effective temperatures and metallicities that are derived
empirically by Kovacs and Jurcsik from the light curves of a large number of
globular cluster and field RRab and RRc stars are compared to theoretical RR
Lyrae models. The strong luminosity dependence of the empirical blue and red
edges (Log L vs Log Teff diagram) is in disagreement with that of both
radiative and convective models. A reexamination of the theoretical
uncertainties in the modelling leads us to conclude that the disagreement is
irreconcilable.

</DOC>
<DOC>
<DOCNO> 69158 </DOCNO>
How to Renormalize the Gap Equation in High Density QCD


  We discuss two technical issues related to the gap equation in high-density
QCD: i) how to obtain the asymptotic solution with well controlled
approximations, and ii) the renormalization of four-quark operators in the
high-density effective field theory.

</DOC>
<DOC>
<DOCNO> 118313 </DOCNO>
One-Line Redshifts and Searches for High-Redshift Lyman-Alpha Emission


  We report the serendipitous discovery of two objects close in projection with
fairly strong emission lines at long wavelength (~9190 A). One (A) seems not to
be hosted by any galaxy brighter than V(555)=27.5, or I(814)=26.7 (Vega-based
3-sigma limits in 1.0 arcsec diameter apertures), while the other line is
associated with a faint (I(814)~24.4) red galaxy (B) offset by 2.7 arcsec and 7
A spectrally. Both lines are broad (FWHM 700 km/s), extended spatially, and
have high equivalent widths (W(A,obs)>1225 A, 95% confidence limit;
W(B,obs)~150 A). No secondary spectral features are detected for galaxy A. Blue
continuum and the marginal detection of a second weak line in the spectrum of
galaxy B is consistent with [OII] (the strong line) and MgII (the weak line) at
z=1.466. By association, galaxy A is likely at z=1.464, implying a rest-frame
equivalent width of the [OII] emission line in excess of 600 A and a projected
separation of 30 kpc for the galaxy pair. Conventional wisdom states that
isolated emission lines with rest-frame equivalent widths larger than ~200 A
are almost exclusively Lyman-alpha. This moderate-redshift discovery therefore
compromises recent claims of high-redshift Lyman-alpha emitters for which other
criteria (i.e., line profile, associated continuum decrements) are not
reported. We discuss observational tests to distinguish Lyman-alpha emitters at
high redshift from foreground systems.

</DOC>
<DOC>
<DOCNO> 118196 </DOCNO>
The Effelsberg Search for Pulsars in the Galactic Centre


  We report the status of a search for pulsars in the Galactic Centre, using a
completely revised and improved high-sensitivity double-horn system at
4.85-GHz. We also present calculations about the success rate of periodicity
searches for such a survey, showing that in contrast to conclusions in recent
literature pulsars can be indeed detected at the chosen search frequency.

</DOC>
<DOC>
<DOCNO> 13896 </DOCNO>
Magnetic Scanning Tunneling Microscopy with a Two-Terminal Non-Magnetic


  We report numerical simulation result of a recently proposed \{P. Bruno,
Phys. Rev. Lett {\bf 79}, 4593, (1997)\} approach to perform magnetic scanning
tunneling microscopy with a two terminal non-magnetic tip. It is based upon the
spin asymmetry effect of the tunneling current between a ferromagnetic surface
and a two-terminal non-magnetic tip. The spin asymmetry effect is due to the
spin-orbit scattering in the tip. The effect can be viewed as a Mott scattering
of tunneling electrons within the tip. To obtain quantitative results we
perform numerical simulation within the single band tight binding model, using
recursive Green function method and Landauer-B\"uttiker formula for
conductance. A new model has been developed to take into account the spin-orbit
scattering off the impurities within the single-band tight-binding model. We
show that the spin-asymmetry effect is most prominent when the device is in
quasi-ballistic regime and the typical value of spin asymmetry is about 5%.

</DOC>
<DOC>
<DOCNO> 100325 </DOCNO>
Algebraic orbifold conformal field theories


  We formulate the unitary rational orbifold conformal field theories in the
algebraic quantum field theory framework. Under general conditions, we show
that the orbifold of a given unitary rational conformal field theories
generates a unitary modular category. Many new unitary modular categories are
obtained. We also show that the irreducible representations of orbifolds of
rank one lattice vertex operator algebras give rise to unitary modular
categories and determine the corresponding modular matrices, which has been
conjectured for some time.

</DOC>
<DOC>
<DOCNO> 99383 </DOCNO>
A Riemann-Roch Theorem For One-Dimensional Complex Groupoids


  We consider a smooth groupoid of the form \Sigma\rtimes\Gamma where \Sigma is
a Riemann surface and \Gamma a discrete pseudogroup acting on \Sigma by local
conformal diffeomorphisms. After defining a K-cycle on the crossed product
C_0(\Sigma)\rtimes\Gamma generalising the classical Dolbeault complex, we
compute its Chern character in cyclic cohomology, using the index theorem of
Connes and Moscovici. This involves in particular a generalisation of the Euler
class constructed from the modular automorphism group of the von Neumann
algebra L^{\infty}(\Sigma)\rtimes\Gamma.

</DOC>
<DOC>
<DOCNO> 80591 </DOCNO>
A Chiral Phase Transition using a Fermion Cluster Algorithm


  The recent solution to the fermion sign problem allows, for the first time,
the use of cluster algorithm techniques to compute certain fermionic path
integrals. To illustrate the underlying ideas behind the progress, a cluster
algorithm is constructed to study the chiral phase transition in a strongly
interacting staggered fermion model with an arbitrary mass term in 3+1
dimensions. Unlike conventional methods there is no difficulty in the cluster
method to approach the chiral (massless) limit. Results using the new algorithm
confirm that the chiral transition falls under the expected universality class.

</DOC>
<DOC>
<DOCNO> 116327 </DOCNO>
Bulk Viscous Cosmological Model with G and Lambda Variables Through


  A model with flat FRW symmetries and G and Lambda variable,is considered in
such a way that the momentum-energy tensor that describes the model is
characterized by a bulk viscosity parameter. In this paper it is showed how to
apply the dimensional method in order to solve the outlined equations in a
trivial way.

</DOC>
<DOC>
<DOCNO> 13616 </DOCNO>
High Accuracy Many-Body Calculational Approaches for Excitations in


  Two state-of-the-art computational approaches: quantum Monte Carlo (QMC),
based on accurate total energies, and GW with exciton effects (GW-BSE), based
on perturbation theory are employed to calculate ionization potentials,
electron affinities, and first excited singlet and triplet energies for the
silane and methane molecules. Results are in excellent agreement between these
dramatically different approaches and with available experiment. The optically
forbidden triplet excitation in silane is predicted to lie roughly 1 eV higher
than previously reported. For methane, the impact of geometry relaxation is
shown to be $\sim$ 2 eV for excited states. Further, in the GW-BSE method, we
demonstrate that inclusion of off-diagonal matrix elements in the self-energy
operator is crucial for an accurate picture.

</DOC>
<DOC>
<DOCNO> 71695 </DOCNO>
QCD at Finite Density


  At sufficiently high temperature and density, quantum chromodynamics (QCD)
predicts phase transition from the hadronic phase to the quark-gluon plasma
phase. Lattice QCD is the most useful tool to investigate this critical
phenomenon, which status is briefly reviewed. The usual problem in the
Lagrangian formulation at finite density is either an incorrect continuum limit
or its complex action and a premature onset of the transition as the chemical
potential is raised. We show how the difficulties are overcome in our
Hamiltonian approach.

</DOC>
<DOC>
<DOCNO> 121038 </DOCNO>
Chandra Observations of the Young Pulsar PSR B0540-69


  The young pulsar PSR B0540-69 was one of the first targets observed with the
Chandra X-Ray Observatory. The high angular resolution of Chandra allows us to
resolve the compact nebula surrounding the pulsar. We have determined a
position for PSR B0540-69 of R.A. = 05h 40m 11s.221, decl. = -69o 19' 54".98
(J2000) with a 1-sigma radial uncertainty of 0.7". Combining our measurements
of the pulsar period with previous measurements covering a span of 12 years, we
derive a braking index of 2.08. The spectrum of the pulsed emission is
consistent with a power-law with a photon index of 1.83 +/- 0.13. The compact
nebula has a softer spectrum with a photon index of 1.85 to 2.26.

</DOC>
<DOC>
<DOCNO> 40419 </DOCNO>
Photon Structure


  The LEP experiments measure the QED and QCD structure of the photon in
deep-inelastic electron-photon scattering. The status of these measurements is
discussed in this short review.

</DOC>
<DOC>
<DOCNO> 67719 </DOCNO>
Brane-Universe in Six Dimensions with Two Times


  Brane-Universe model embedded in 6-dimensional space-time with the signature
(2+4) is considered. A matter is gravitationally trapped in three space
dimensions, but both time-like directions are open. Choosing of the dimension
and the signature of the model is initiated with the conformal symmetry for
massless particles and any point in our world can be (1+1) string-like object.

</DOC>
<DOC>
<DOCNO> 69092 </DOCNO>
Nuclear Effects on the Extraction of Neutron Structure Functions


  Nuclear effects in light nuclei due to the presence of spin-one isosinglet
6-quark clusters are investigated. The quark distributions of 6-quark clusters
are obtained by using a perturbative QCD (pQCD) based framework, which allows
us to get a good description of the ratio of the deuteron structure function to
the free nucleon structure function. Nuclear effects on the extraction of the
neutron structure functions $F_2^n$ and $g_1^n$ are estimated. We find that the
effect on the extracted spin-dependent neutron structure function is very
different from that on the spin-independent neutron structure function. The
effect enhances the Bjorken sum by about 10%, whereas its correction to the
Gottfried sum is rather small. The formalism for calculating nuclear effects is
further used to evaluate the spin-dependent structure function of the $^3$He
nucleus and a good self-consistent check is obtained.

</DOC>
<DOC>
<DOCNO> 121097 </DOCNO>
On the coupling between different species during recombination


  Measurements of fluctuations in the Cosmic Microwave Background Radiation
(CMBR) is one of the most promising methods for measuring the fundamental
cosmological parameters. However, in order to infer parameters from precision
measurements it is necessary to calculate the theoretical fluctuation spectrum
to at least the measurement accuracy. Standard treatments assume that
electrons, ions and neutral hydrogen are very tightly coupled during the entire
recombination history, and that the baryon-photon plasma can be treated as a
two-fluid system consisting of baryons and photons interacting via Thomson
scattering. We investigate the validity of this approximation by explicitly
writing down and solving the full set of Boltzmann equations for electrons,
ions, neutral hydrogen and photons. The main correction to the standard
treatment is from including Rayleigh scattering between photons and neutral
hydrogen, a change of less than 0.1% in the CMBR power spectrum. Our conclusion
is thus that the standard treatment of the baryon-photon system is a very good
approximation, better than any possible measurement accuracy.

</DOC>
<DOC>
<DOCNO> 8482 </DOCNO>
Johnson-Nyquist noise in films and narrow wires


  The Johnson-Nyquist noise in narrow wires having a transverse size smaller
than the screening length is shown to be white up to the frequency $D/L^2$ and
to decay at higher frequencies as $\omega^{-{1/2}}$. In two-dimensional films
having a thickness smaller than the screening length, the Johnson-Nyquist noise
is predicted to be frequency independent up to the frequency $\sigma_{2D}/L$
and to have a {\it universal} $1/\omega$ spectrum at higher frequencies. These
results are contrasted with the conventional noise spectra in neutral and
three-dimensional charged liquids.

</DOC>
<DOC>
<DOCNO> 84993 </DOCNO>
Post-Newtonian Gravitational Radiation and Equations of Motion via


  We present a self-contained framework called Direct Integration of the
Relaxed Einstein Equations (DIRE) for calculating equations of motion and
gravitational radiation emission for isolated gravitating systems based on the
post-Newtonian approximation. We cast the Einstein equations into their
``relaxed'' form of a flat-spacetime wave equation together with a harmonic
gauge condition, and solve the equations formally as a retarded integral over
the past null cone of the field point (chosen to be within the near zone when
calculating equations of motion, and in the far zone when calculating
gravitational radiation). The ``inner'' part of this integral(within a sphere
of radius $\cal R \sim$ one gravitational wavelength) is approximated in a
slow-motion expansion using standard techniques; the ``outer'' part, extending
over the radiation zone, is evaluated using a null integration variable. We
show generally and explicitly that all contributions to the inner integrals
that depend on $\cal R$ cancel corresponding terms from the outer integrals,
and that the outer integrals converge at infinity, subject only to reasonable
assumptions about the past behavior of the source. The method cures defects
that plagued previous ``brute-force'' slow-motion approaches to motion and
gravitational radiation for isolated systems. We detail the procedure for
iterating the solutions in a weak-field, slow-motion approximation, and derive
expressions for the near-zone field through 3.5 post-Newtonian order in terms
of Poisson-like potentials.

</DOC>
<DOC>
<DOCNO> 174478 </DOCNO>
Energy resolution and energy-light response of CsI(TI) scintillators for


  This article describes the crystal selection and quality control utilized to
develop and calibrate a high resolution array of CsI(TI) scintillator crystals
for the detection of energetic charged particles. Alpha sources are used to
test the light output variation due to thallium doping gradients. Selection of
crystals with better than 1% non-uniformity in light output is accomplished
using this method. Tests with 240 MeV alpha beam reveal that local light output
variations within each of the tested CsI(TI) crystals limit the resolution to
about 0.5%. Charge and mass dependences in the energy - light output
relationship are determined by calibrating with energetic projectile
fragmentation beams.

</DOC>
<DOC>
<DOCNO> 7775 </DOCNO>
Many-body spin related phenomena in ultra-low-disorder quantum wires


  Zero length quantum wires (or point contacts) exhibit unexplained conductance
structure close to 0.7 X 2e^2/h in the absence of an applied magnetic field. We
have studied the density- and temperature-dependent conductance of
ultra-low-disorder GaAs/AlGaAs quantum wires with nominal lengths l=0 and 2 mu
m, fabricated from structures free of the disorder associated with modulation
doping. In a direct comparison we observe structure near 0.7 X 2e^2/h for l=0
whereas the l=2 mu m wires show structure evolving with increasing electron
density to 0.5 X 2e^2/h in zero magnetic field, the value expected for an ideal
spin-split sub-band. Our results suggest the dominant mechanism through which
electrons interact can be strongly affected by the length of the 1D region.

</DOC>
<DOC>
<DOCNO> 121283 </DOCNO>
Parsec-Scale Blazar Monitoring: Proper Motions


  We present proper motions obtained from a dual frequency, six-epoch, VLBA
polarization experiment monitoring a sample of 12 blazars. The observations
were made at 15 GHz and 22 GHz at bi-monthly intervals over 1996. Ten of the
eleven sources for which proper motion could be reliably determined are
superluminal. Only J2005+77 has no superluminal components. Three sources
(OJ287, J1224+21, and J1512-09) show motion faster than 10h^{-1}c, requiring
$\gamma_{pattern}$ of at least 10h^{-1}c (H_0 = 100h km/s/Mpc). We compare our
results to those in the literature and find motions outside the previously
observed range for four sources. While some jet components exhibit significant
non-radial motion, most motion is radial. In at least two sources there are
components moving radially at significantly different structural position
angles. In five of six sources (3C120, J1224+21, 3C273, 3C279, J1512-09, and
J1927+73) that have multiple components with measurable proper motion, the
innermost component is significantly slower than the others, suggesting that
acceleration occurs in the jet. In the motions of individual components we
observe at least one decelerating motion and two ``bending'' accelerations
which tend to align their motions with larger scale structure. We also discuss
in detail our procedures for obtaining robust kinematical results from
multi-frequency VLBI data spanning several epochs.

</DOC>
<DOC>
<DOCNO> 69896 </DOCNO>
Soft diffraction and the elastic slope at Tevatron and LHC energies: a


  We present a formalism for high energy soft processes, mediated by Pomerons,
which embodies pion-loop insertions in the Pomeron trajectory, rescattering
effects via a two-channel eikonal and high-mass diffractive dissociation. It
describes all the main features of the data throughout the ISR to Tevatron
energy interval. We give predictions for soft diffractive phenomena at the LHC
energy, and we calculate the different survival probabilities of rapidity gaps
which occur in various diffractive processes.

</DOC>
<DOC>
<DOCNO> 85579 </DOCNO>
The Role of Elliptic Operators in the Initial-Value Problem for General


  The Arnowitt-Deser-Misner (ADM) equations are deeply intertwined with
discrete spectral resolutions of an elliptic operator of Laplace type
associated with the spacelike hypersurfaces which foliate the space-time
manifold, and the non-linearities of the four-dimensional hyperbolic theory are
mapped into the potential term occurring in this operator. The ADM equations
are here re-expressed as a coupled first-order system for the induced metric
and the trace-free part of the extrinsic-curvature tensor, and their
formulation in terms of integral equations is studied.

</DOC>
<DOC>
<DOCNO> 151186 </DOCNO>
A Note on the Quadratic Divergence in Hybrid Regularization


  We consider the quadratic divergence of the Yang-Mills theory when we use the
hybrid regularization method consisting of the higher covariant derivative
terms and the Pauli-Villars fields. By the explicit calculation of the
diagrams, we show that the higher derivative terms for the ghost fields are
necessary for the complete cancellation of the quadratic divergence.

</DOC>
<DOC>
<DOCNO> 100141 </DOCNO>
PT invariant Non-Hermitian Potentials with Real QES Eigenvalues


  We show that at least the quasi-exactly solvable eigenvalues of the
Schr\"odinger equation with the potential $V(x) = -(\zeta \cosh 2x -iM)^2$ as
well as the periodic potential $V(x) = (\zeta \cos 2\theta -iM)^2$ are real for
the PT-invariant non-Hermitian potentials in case the parameter $M$ is any odd
integer. We further show that the norm as well as the weight functions for the
corresponding weak orthogonal polynomials are also real.

</DOC>
<DOC>
<DOCNO> 85463 </DOCNO>
(Quantum) Space-Time as a Statistical Geometry of Fuzzy Lumps and the


  We develop a kind of pregeometry consisting of a web of overlapping fuzzy
lumps which interact with each other. The individual lumps are understood as
certain closely entangled subgraphs (cliques) in a dynamically evolving network
which, in a certain approximation, can be visualized as a time-dependent random
graph. This strand of ideas is merged with another one, deriving from ideas,
developed some time ago by Menger et al, that is, the concept of probabilistic-
or random metric spaces, representing a natural extension of the metrical
continuum into a more microscopic regime. It is our general goal to find a
better adapted geometric environment for the description of microphysics. In
this sense one may it also view as a dynamical randomisation of the causal-set
framework developed by e.g. Sorkin et al. In doing this we incorporate, as a
perhaps new aspect, various concepts from fuzzy set theory.

</DOC>
<DOC>
<DOCNO> 118173 </DOCNO>
Numerical simulation of accretion discs in close binary systems and


  The history of hydrodynamic numerical simulations for accretion disks in
close binary systems is reviewed, in which emphasis is placed, in particular,
on the facts that spiral shock waves were numerically found in 1986 by
researchers including one of the present authors and that spiral structure was
discovered in IP Pegasi in 1997 by Steeghs et al. The results of our two and
three-dimensional numerical simulations in recent years are then summarized,
with comparison being made with observations.

</DOC>
<DOC>
<DOCNO> 122468 </DOCNO>
The local Hubble flow: a manifestation of dark energy


  Our local environment at $r<10$ Mpc expands linearly and smoothly, as if
ruled by a uniform matter distribution, while observations show the very clumpy
local universe. This is a long standing enigma in cosmology. We argue that the
recently discovered vacuum or quintessence (dark energy (DE) component with the
equation of state $p_Q = w \rho_Q c^2$, $w \in [-1,0)$) from observations of
the high-redshift universe may also manifest itself in the properties of the
very local Hubble flow. We introduce the concept of the critical distance $r_Q$
where the repulsive force of dark energy starts to dominate over the gravity of
a mass concentration. For the Local Group $r_Q$ is about 1.5 Mpc. Intriguingly,
at the same distance 1.5 Mpc the linear and very "cold" Hubble flow emerges,
with about the global Hubble constant. We also consider the critical epoch
$t_Q$, when the DE antigravity began to dominate over the local matter gravity
for a galaxy which at the present epoch is in the local DE dominated region.
Our main result is that the homogeneous dark energy component, revealed by SNIa
observations, resolves the old confrontation between the local Hubble flow and
local highly non-uniform, fractal matter distribution. It explains why the
Hubble law starts on the outskirts of the Local Group, with the same Hubble
constant as globally and with a remarkably small velocity dispersion.

</DOC>
<DOC>
<DOCNO> 12343 </DOCNO>
Commensurate-Incommensurate transition in the melting process of the


  The melting process of the orbital order in
 Pr0.5Ca0.5MnO3 single crystal has been studied in detail as a function of
temperature by neutron diffraction. It is demonstrated that a
commensurate-incommensurate (C-IC) transition of the orbital ordering takes
place in a bulk sample, being consistent with the electron diffraction studies.
The lattice structure and the transport properties go through drastic changes
in the IC orbital ordering phase below the charge/orbital ordering temperature
 Tco/oo, indicating that the anomalies are intimately related to the partial
disordering of the orbital order, unlike the consensus that it is related to
the charge disordering process. For the same T range, partial disorder of the
orbital ordering turns on the ferromagnetic spin fluctuations which were
observed in a previous neutron scattering study.

</DOC>
<DOC>
<DOCNO> 122082 </DOCNO>
Observations of Ammonia in External Galaxies. II. Maffei 2


  The ammonia (J,K) = (1,1), (2,2), (3,3), and (4,4) transitions at 23.7 --
24.1 GHz region were searched for in a nearby galaxy Maffei 2 to study relation
between molecular abundances and physical conditions in galaxies. The (1,1),
(2,2), and (3,3) emission lines were clearly detected. The rotational
temperatures and ortho-to-para abundance ratios obtained are about 30 K and
about 2.6, respectively. The abundance of NH3 relative to H2 in Maffei 2 was
found to be the largest among galaxies where NH3 is already detected, and the
abundance in Maffei 2 is more than an order of magnitude larger than the
already reported upper limit in M82. Hence, we further confirmed the
systematically peculiar molecular abundance in the aspect of formation
mechanisms of molecules already reported in M82.

</DOC>
<DOC>
<DOCNO> 70163 </DOCNO>
Real and Virtual Compton Scattering off the Nucleon


  A review is given of the very recent developments in the fields of real and
virtual Compton scattering off the nucleon. Both real and virtual Compton
scattering reactions are discussed at low outgoing photon energy where one
accesses polarizabilities of the nucleon. The real Compton scattering at large
momentum transfer is discussed which is asymptotically a tool to obtain
information on the valence quark wave function of the nucleon. The rapid
developments in deeply virtual Compton scattering and associated meson
electroproduction reactions at high energy, high photon virtuality and small
momentum transfer to the nucleon are discussed. A unified theoretical
description of those processes has emerged over the last few years, which gives
access to new, generalized parton distributions. The experimental status and
perspectives in these fields are also discussed.

</DOC>
<DOC>
<DOCNO> 102202 </DOCNO>
On the Cohomology of Theta Divisors of Hyperelliptic Jacobians


  We prove that k-th singular cohomology group of the complement of the theta
divisor in a hyperelliptic Jacobian is isomorphic to the k-th fundamental
representation of the symplectic group Sp(2g,C). This is one of the conjectures
in our previous paper.

</DOC>
<DOC>
<DOCNO> 99768 </DOCNO>
Some Aspects of Deformations of Supersymmetric Field Theories


  We investigate some aspects of Moyal-Weyl deformations of superspace and
their compatibility with supersymmetry. For the simplest case, when only
bosonic coordinates are deformed, we consider a four dimensional supersymmetric
field theory which is the deformation of the Wess-Zumino renormalizable theory
of a chiral superfield. We then consider the deformation of a free theory of an
abelian vector multiplet, which is a non commutative version of the rank one
Yang-Mills theory. We finally give the supersymmetric version of the
$\alpha'\mapsto 0$ limit of the Born-Infeld action with a B-field turned on,
which is believed to be related to the non commutative U(1) gauge theory.

</DOC>
<DOC>
<DOCNO> 101459 </DOCNO>
The Topological Structure of Contact and Symplectic Quotients


  We show that if a Lie group acts properly on a co-oriented contact manifold
preserving the contact structure, then the contact quotient is topologically a
stratified space (in the sense that a neighborhood of a point in the quotient
is a product of a disk with a cone on a compact stratified space). As a
corollary, we obtain that symplectic quotients for proper Hamiltonian actions
are topologically stratified spaces in this strong sense thereby extending and
simplifying previous work.

</DOC>
<DOC>
<DOCNO> 14149 </DOCNO>
Phase diagram of the three-dimensional Gaussian random field Ising


  With the help of the replica exchange Monte Carlo method and the improved
Monte Carlo renormalization-group scheme, we investigate over a wide area in
the phase diagram of the Gaussian random field Ising model on the simple cubic
lattice. We found that the phase transition at a weak random field belongs to
the same universality class as the zero-temperature phase transition. We also
present a possible scenario for the replica symmetry breaking transition.

</DOC>
<DOC>
<DOCNO> 8105 </DOCNO>
Extension of the Brinkman-Rice picture and the Mott transition


  In order to explain the metal-Mott-insulator transition, the Brinkman-Rice
(BR) picture is extended. In the case of less than one as well as one electron
per atom, the on-site Coulomb repulsion is given by U={kappa}{rho}^2U_c by
averaging the electron charge per atom over all atomic sites, where {kappa} is
the correlation strength of U, {rho} is the band filling factor, and U_c is the
critical on-site Coulomb energy. The effective mass of a quasiparticle is found
to be m*/m=1/{1-{kappa}^2{rho}^4} for 0<{kappa}{rho}^2<1 and seems to follow
the heat capacity data of Sr_{1-x}La_xTiO_3 and YBa_2Cu_3O_{7-delta} at
{kappa}=1 and 0<{kappa}{rho}^2<1. The Mott transition of the first order occurs
at {kappa}{rho}^2=1 and a band-type metal-insulator transition takes place at
{kappa}{rho}^2=0. This Mott transition is compared with that in the d=infinity
Hubbard model. The effective mass for 2D-DOS instead of the vHs can be used for
the mechanism of high T_c superconductivity.

</DOC>
<DOC>
<DOCNO> 119863 </DOCNO>
The response of an accretion disc to an inclined dipole with application


  We compute the warping of a disc induced by an inclined dipole. We consider a
magnetised star surrounded by a thin Keplerian diamagnetic disc with an inner
edge that corotates with the star. We suppose the stellar field is a dipole
with an axis that is slightly misaligned with the stellar rotation axis. The
rotation axes of the disc material orbiting at large distances from the star
and that of the star are supposed to coincide. The misalignment of the magnetic
and rotation axes results in the magnetic pressure not being the same on the
upper and lower surfaces of the disc. The resultant net vertical force produces
a warp which appears stationary in a frame corotating with the star. We find
that, if viscosity is large enough (alpha on the order of 0.01-0.1) to damp
bending waves as they propagate away, a smoothly varying warp of the inner
region of the disc is produced. The amplitude of the warp can easily be on the
order of ten percent of the disc inner radius for reasonably small misalignment
angles (less than 30 degrees). Viscous damping also introduces a phase shift
between the warp and the forcing torque, which results in the locations of
maximum elevation above the disc forming a trailing spiral pattern. We apply
these results to recent observations of AA Tau, and show that the variability
of its light curve, which occurs with a period comparable to the expected
stellar rotation period, could be due to obscuration produced by a warp
configuration of the type we obtain.

</DOC>
<DOC>
<DOCNO> 152534 </DOCNO>
The Structure of D2-Branes in the Presence of an RR field


  A Born-Infeld theory describing a D2-brane coupled to a 3-form RR potential
is reconsidered in order to determine the dominant nonsingular tunneling
trajectory with finite action which determines the decay rate of the brane.

</DOC>
<DOC>
<DOCNO> 151960 </DOCNO>
Perturbative ultraviolet and infrared dynamics of noncommutative quantum


  Perturbative aspects of ultraviolet and infrared dynamics of noncommutative
quantum field theory is examined in detail. It is observed that high loop
momentum contribution to the nonplanar diagram develops a new infrared
singularity with respect to the external momentum. This singular behavior is
closely related to that of ultraviolet divergence of planar diagram. It is also
shown that such a relation is precise in noncommutative Yang-Mills theory, but
the same feature does not persist in noncommutative generalization of QED.

</DOC>
<DOC>
<DOCNO> 178915 </DOCNO>
On the free volume in nuclear multifragmentation


  In many statistical multifragmentation models the volume available to the $N$
nonoverlapping fragments forming a given partition is a basic ingredient
serving to the simplification of the density of states formula. One therefore
needs accurate techniques for calculating this quantity. While the direct
Monte-Carlo procedure consisting of randomly generating the fragments into the
freeze-out volume and counting the events with no overlapped fragments is
numerically affordable only for partitions with small $N$, the present paper
proposes a Metropolis - type simulation which allows accurate evaluations of
the free volume even for cases with large $N$. This procedure is used for
calculating the available volume for various situations. Though globally this
quantity has an exponential dependence on $N$, variations of orders of
magnitude for partitions with the same $N$ may be identified. A parametrization
based on the virial approximation adjusted with a calibration function,
describing very well the variations of the free volume for different partitions
having the same $N$ is proposed. This parametrization was successfully tested
within the microcanonical multifragmentation model from [Al. H. Raduta and Ad.
R. Raduta, Phys. Rev. C {\bf 55}, 1344 (1997); {\it ibid.}, {\bf 56}, 2059
(1997)]. Finally, it is proven that parametrizations of the free volume solely
dependent on $N$ are rather inadequate for multifragmentation studies producing
important deviations from the exact results.

</DOC>
<DOC>
<DOCNO> 120523 </DOCNO>
Carbon in the N159/N160 Complex of the Large Magellanic Cloud


  We present a study of carbon in N159/N160, an HII region complex in the low
metallicity Large Magellanic Cloud. We have mapped this region, which comprises
four distinct molecular clouds spanning a wide range of star-formation
activity, in four transitions: 13CO (1-0) CO (2-1) and (4-3), and [CI] (1-0).
Combining these data with existing [CII] observations provides a complete
picture of the predominant forms of carbon in the gas phase of the ISM. The new
CO (2-1) data show that the complex is immersed in an envelope of extended, low
level emission, undetected by previous (1-0) mapping efforts. The CO
(2-1)/(1-0) ratio in this envelope is >~3, a value consistent with optically
thin CO emission. The envelope is also relatively bright in [CI] and [CII], and
calculations show that it is mostly photodissociated: it appears to be
translucent (Av<1). Neutral carbon emission in the complex unexpectedly peaks
at the quiescent southern cloud (N159S). In the northern portion of the map
(the N160 nebula), the HII regions prominent in [CII] correspond to holes in
the [CI] distribution. Overall we find that, while the [CII]/CO ratio is
enhanced with respect to similar complexes in the Milky Way, the [CI]/CO ratio
appears to be similar or reduced.

</DOC>
<DOC>
<DOCNO> 10815 </DOCNO>
Random Matrix approach to the crossover from Wigner to Poisson


  We analyze a class of parametrized Random Matrix models, introduced by
Rosenzweig and Porter, which is expected to describe the energy level
statistics of quantum systems whose classical dynamics varies from regular to
chaotic as a function of a parameter. We compute the generating function for
the correlations of energy levels, in the limit of infinite matrix size. Our
computations show that for a certain range of values of the parameter, the
energy-level statistics is given by that of the Wigner-Dyson ensemble. For
another range of parameter values, one obtains the Poisson statistics of
uncorrelated energy levels. However, between these two ranges, new statistics
emerge, which is neither Poissonnian nor Wigner. The crossover is measured by a
renormalized coupling constant. The model is exactly solved in the sense that,
in the limit of infinite matrix size, the energy-level correlation functions
and their generating function are given in terms of a finite set of integrals.

</DOC>
<DOC>
<DOCNO> 151051 </DOCNO>
Robustness and diffusion of pointer states


  Classical properties of an open quantum system emerge through its interaction
with other degrees of freedom (decoherence). We treat the case where this
interaction produces a Markovian master equation for the system. We derive the
corresponding distinguished local basis (pointer basis) by three methods. The
first demands that the pointer states mimic as close as possible the local
non-unitary evolution. The second demands that the local entropy production be
minimal. The third imposes robustness on the inherent quantum and emerging
classical uncertainties. All three methods lead to localized Gaussian pointer
states, their formation and diffusion being governed by well-defined quantum
Langevin equations.

</DOC>
<DOC>
<DOCNO> 12644 </DOCNO>
Multiplicity of Ordered Phases in Frustrated Systems Obtained from


  Random quenched dilution of the triangular-lattice antiferromagnetic Ising
model locally relieves frustration, leading to ordering phenomena. We have
studied this system, under such dilution of one sublattice, using hard-spin
mean-field theory. After a threshold dilution, two sublattices develop non-zero
magnetizations of equal magnitude and opposite signs, as all three sublattices
exhibit spin-glass order. In this phase, multiple sets of ordered solutions
occur. A phase diagram is obtained in dilution fraction and temperature.

</DOC>
<DOC>
<DOCNO> 102164 </DOCNO>
The mapping class group of a genus two surface is linear


  In this paper we construct a faithful representation of the mapping class
group of the genus two surface into a group of matrices over the complex
numbers. Our starting point is the Lawrence-Krammer representation of the braid
group B_n, which was shown to be faithful by Bigelow and Krammer. We obtain a
faithful representation of the mapping class group of the n-punctured sphere by
using the close relationship between this group and B_{n-1}. We then extend
this to a faithful representation of the mapping class group of the genus two
surface, using Birman and Hilden's result that this group is a Z_2 central
extension of the mapping class group of the 6-punctured sphere. The resulting
representation has dimension sixty-four and will be described explicitly. In
closing we will remark on subgroups of mapping class groups which can be shown
to be linear using similar techniques.

</DOC>
<DOC>
<DOCNO> 8527 </DOCNO>
Nature of 45 degree vortex lattice reorientation in tetragonal


  The transformation of the vortex lattice in a tetragonal superconductor which
consists of its 45 degree reorientation relative to the crystal axes is studied
using the nonlocal London model. It is shown that the reorientation occurs as
two successive second order (continuous) phase transitions. The transition
magnetic fields are calculated for a range of parameters relevant for
borocarbide superconductors in which the reorientation has been observed.

</DOC>
<DOC>
<DOCNO> 69267 </DOCNO>
On the hadron production from the quark-gluon plasma phase in


  We describe the quark gluon plasma (QGP) as a thermalized quark-gluon system,
the thermalized QGP phase of QCD. The hadronization of the thermalized QGP
phase is given in a way resembling a coalescence model with correlated quarks
and anti-quarks. The input parameters of the approach are the spatial volumes
of the hadronization. We introduce three dimensionless parameters C_M, C_B and
C_\bar{B} related to the spatial volumes of the production of low-lying mesons
(M), baryons (B) and antibaryons (\bar{B}). We show that at the temperature T=
175 MeV our predictions for the ratios of multiplicities agree good with the
presently available set of hadron ratios measured for various experiments given
by NA44, NA49, NA50 and WA97 Collaborations on Pb+Pb collisions at 158
GeV/nucleon, NA35 Collaboration on S+S collisions and NA38 Collaboration on O+U
and S+U collisions at 200 GeV/nucleon.

</DOC>
<DOC>
<DOCNO> 71860 </DOCNO>
Quons in Relativistic Theories Must be Bosons or Fermions


  The quon algebra describes particles, ``quons,'' that are neither fermions
nor bosons using a label q that parametrizes a smooth interpolation between
bosons (q = +1) and fermions (q = -1). We derive ``conservation of statistics''
relations for quons in relativistic theories, and show that in relativistic
theories quons must be either bosons or fermions.

</DOC>
<DOC>
<DOCNO> 12077 </DOCNO>
Ab initio study of BaTiO3 and PbTiO3 surfaces in external electric


  For the ferroelectric perovskite compounds BaTiO3 and PbTiO3, we have studied
the effects of external electric fields on the structural properties of the
(001) surfaces. The field-induced changes in the surface interlayer spacings
and bucklings have been calculated using a first-principles
ultrasoft-pseudopotential approach, and the change of the polarization and the
ferroelectric distortions in the surface layers have been obtained. The
surfaces are represented by periodically repeated slabs, and an external dipole
layer is included in the vacuum region of the supercells to control the
electric field normal to the surfaces. The influence of the electrical boundary
conditions on the ferroelectric properties of the slabs is discussed. In the
case of a vanishing internal electric field, our study indicates that even very
thin slabs can show a ferroelectric instability.

</DOC>
<DOC>
<DOCNO> 68063 </DOCNO>
Higgs Production: A Comparison of Parton Showers and Resummation


  The search for the Higgs boson(s) is one of the major priorities at the
upgraded Fermilab Tevatron and at the CERN Large Hadron Collider (LHC). Monte
Carlo event generators (MCs) are heavily utilized to extract and interpret the
Higgs signal, which depends on the details of the multiple soft-gluon emission
from the initial state partons in hadronic collisions. Thus, it is crucial to
establish the reliability of the MCs used by the experimentalists. In this
paper, the MC based parton shower formalism is compared to that of an analytic
resummation calculation. Theoretical input, predictions and, where they exist,
data for the transverse momentum distribution of Higgs bosons, $Z^0$ bosons,
and photon pairs are compared for the Tevatron and the LHC. This comparison is
useful in understanding the strengths and the weaknesses of the different
theoretical approaches, and in testing their reliability.

</DOC>
<DOC>
<DOCNO> 150580 </DOCNO>
Manifestly N=3 supersymmetric Euler-Heisenberg action in light-cone


  We find a manifestly N=3 supersymmetric generalization of the
four-dimensional Euler-Heisenberg (four-derivative, or F^4) part of the
Born-Infeld action in light-cone gauge, by using N=3 light-cone superspace.

</DOC>
<DOC>
<DOCNO> 70644 </DOCNO>
Possibility of Large FSI Phases in Light of $B\to K\pi$ & $\pi\pi$ Data


  After briefly reviewing how data indicated that factorization seems to work
in observed two body charmless modes, {\it if one takes $\gamma \gtap
90^\circ$}, we point out that the $K^0\pi^0$ mode seems too large. This and
other hints suggest that perhaps not only $\gamma$ is large, but rescattering
phase $\delta$ could be sizable as well.

</DOC>
<DOC>
<DOCNO> 68685 </DOCNO>
Polarized antiquark distributions from chiral quark-soliton model:


  In these short notes we present a parametrization of the results obtained in
the chiral quark-soliton model for polarized antiquark distributions
$\Delta\bar u$, $\Delta\bar d$ and $\Delta\bar s$ at a low normalization point
around mu=0.6 GeV.

</DOC>
<DOC>
<DOCNO> 101600 </DOCNO>
Maximal subalgebras of vector fields for equivariant quantizations


  The elaboration of new quantization methods has recently developed the
interest in the study of subalgebras of the Lie algebra of polynomial vector
fields over a Euclidean space. In this framework, these subalgebras define
maximal equivariance conditions that one can impose on a linear bijection
between observables that are polynomial in the momenta and differential
operators.Here, we determine which finite dimensional graded Lie subalgebras
are maximal. In order to characterize these, we make use of results of
Guillemin, Singer and Sternberg and Kobayashi and Nagano.

</DOC>
<DOC>
<DOCNO> 8726 </DOCNO>
Critical chain length and superconductivity emergence in


  The oxygen-order dependent emergence of superconductivity in YBa2Cu3O6+x is
studied, for the first time in a comparative way, on pair samples having the
same oxygen content and thermal history, but different Cu(1)Ox chain
arrangements deriving from their intercalated and deintercalated nature.
Structural and electronic non-equivalence of pairs samples is detected in the
critical region and found to be related, on microscopic scale, to a different
average chain length, which, on being experimentally determined by nuclear
quadrupole resonance (NQR), sheds new light on the concept of critical chain
length for hole doping efficiency.

</DOC>
<DOC>
<DOCNO> 11026 </DOCNO>
Ab-initio calculations of exchange interactions, spin-wave stiffness


  We have calculated Heisenberg exchange parameters for bcc-Fe, fcc-Co, and
fcc-Ni using the scalar-relativistic spin-polarized Green function technique
within the tight-binding linear muffin-tin orbital method and by employing the
magnetic force theorem to calculate total energy changes associated with a
local rotation of magnetization directions. We have also determined spin-wave
stiffness constants and found the dispersion curves for metals in question
employing the Fourier transform of calculated Heisenberg exchange parameters.
Curie temperatures were calculated both in the mean-field approximation and
within the Green function random phase approximation. The latter results were
found to be in a better agreement with available experimental data.

</DOC>
<DOC>
<DOCNO> 100717 </DOCNO>
Projectively equivariant symbol calculus for bidifferential operators


  We prove the existence and uniqueness of a *projectively equivariant symbol
map*, which is an isomorphism between the space of bidifferential operators
acting on tensor densities over $R^n$ and that of their symbols, when both are
considered as modules over an imbedding of $sl(n+1,\R)$ into polynomial vector
fields. The coefficients of the bidifferential operators are densities of an
arbitrary weight. We obtain the result for all values of this weight, except
for a set of critical ones, which does not contain 0. In the case of second
order operators, we give explicit formulas and examine in detail the critical
values.

</DOC>
<DOC>
<DOCNO> 70051 </DOCNO>
Collective Evolution of Hot QCD Matter from the QGP to Freeze-Out


  We present results on the evolution of <p_t> with energy, for hadrons
emerging from hadronization of a quark-gluon plasma possibly produced in
high-energy heavy-ion collisions. We find that BNL-RHIC energy corresponds to
the previously predicted plateau of <p_t>, reminiscent of the assumed
first-order QCD phase transition. Heavy hadrons are the best messengers of the
transverse flow stall.

</DOC>
<DOC>
<DOCNO> 83057 </DOCNO>
Effect of different packet sizes on RED performance


  We consider the adaptation of random early detection (RED) as an active queue
management algorithm for TCP traffic in Internet gateways where different
maximum transfer units (MTUs) are used. We studied the two existing RED
variants and point out a weakness in both. The first variant where the drop
probability is independent from the packet size discriminates connections with
smaller MTUs. The second variant results in a very high Packet Loss Ratio
(PLR), and as a consequence low goodput, for connections with higher MTUs. We
show that fairness in terms of loss and goodput can be supplied through an
appropriate setting of the RED algorithm.

</DOC>
<DOC>
<DOCNO> 178588 </DOCNO>
Description of Multi Quasi Particle Bands by the Tilted Axis Cranking


  The selfconsistent cranking approach is extended to the case of rotation
about an axis which is tilted with respect to the principal axes of the
deformed potential (Tilted Axis Cranking). Expressions for the energies and the
intra bands electromagnetic transition probabilities are given.
  The mean field solutions are interpreted in terms of quantal rotational
states. The construction of the quasiparticle configurations and the
elimination of spurious states is discussed. The application of the theory to
high spin data is demonstrated by analyzing the multi quasiparticle bands in
the nuclide-s with $N=102,103$ and $Z=71,72,73$.

</DOC>
<DOC>
<DOCNO> 119339 </DOCNO>
Electron-positron outflow from black holes and the formation of winds


  The collapse of young massive stars or the coalescence of a black
hole-neutron star binary is expected to give rise to a black hole-torus system.
When the torus is strongly magnetized, the black hole produces
electron-positron outflow along open magnetic field-lines. Through curvature
radiation in gaps, this outflow rapidly develops into a $e^\pm\gamma$-wind,
which is ultra-relativistic and of low comoving density, proposed here as a
possible input to GRB fireball models.

</DOC>
<DOC>
<DOCNO> 8677 </DOCNO>
Sublattice Magnetization and N\'eel Transition in the 2D Quantum


  We present an analytic expression for the finite temperature sublattice
magnetization, at the Josephson scale, in two dimensional quantum
antiferromagnets with short range N\'eel order. Our expression is able to
reproduce both the qualitative behaviour of the phase diagram $M(T)/M_{0}$ and
the experimental values of the N\'eel temperature $T_{N}$ for either doped
YBa$_{2}$Cu$_{3}$O$_{6.15}$ and stoichiometric La$_{2}$CuO$_{4}$.

</DOC>
<DOC>
<DOCNO> 119219 </DOCNO>
On the Role of Irradiation and Evaporation in Strongly Irradiated


  We examine a new paradigm to account for the exponential decay seen in the
light curves of some of the bright X-ray novae. These systems show an
exponential decay in soft X-rays with an e-folding time constant of ~30 d. We
investigate a scenario in which evaporation of matter into a corona is the
dominant mass removal mechanism from the accretion disk. We utilize the thermal
evaporative instability discovered by Shaviv and Wehrse. First we parametrize
local mass loss rates from the disk (fitted to vertical structure computations
of the optically thin structure using the photoionization code CLOUDY), and
then we utilize the scalings in our numerical time dependent model for the
decay. Both the ~30 d e-folding time scale for the decay and the secondary
maximum with its rapid rise time ~1-3 d which is seen in the X-ray nova light
curves can be produced by adjusting the strength of the evaporation.

</DOC>
<DOC>
<DOCNO> 170602 </DOCNO>
Characteristics of Quantum-Classical Correspondence for Two Interacting


  The conditions of quantum-classical correspondence for a system of two
interacting spins are investigated. Differences between quantum expectation
values and classical Liouville averages are examined for both regular and
chaotic dynamics well beyond the short-time regime of narrow states. We find
that quantum-classical differences initially grow exponentially with a
characteristic exponent consistently larger than the largest Lyapunov exponent.
We provide numerical evidence that the time of the break between the quantum
and classical predictions scales as log(${\cal J}/ \hbar$), where ${\cal J}$ is
a characteristic system action. However, this log break-time rule applies only
while the quantum-classical deviations are smaller than order hbar. We find
that the quantum observables remain well approximated by classical Liouville
averages over long times even for the chaotic motions of a few
degree-of-freedom system. To obtain this correspondence it is not necessary to
introduce the decoherence effects of a many degree-of-freedom environment.

</DOC>
<DOC>
<DOCNO> 102647 </DOCNO>
Coherent Sheaves on Configuration Schemes


  We introduce and study configuration schemes, which are obtained by
``glueing'' usual schemes along closed embeddings. The category of coherent
sheaves on a configuration scheme is investigated. Smooth configuration schemes
provide alternative ``resolutions of singularities'' of usual singular schemes.
We consider in detail the case when the singular scheme is a union of
hyperplanes in a projective space.

</DOC>
<DOC>
<DOCNO> 170479 </DOCNO>
Entanglement of Formation and Conditional Information Transmission


  We show that the separability of states in quantum mechanics has a close
counterpart in classical physics, and that conditional mutual information
(a.k.a. conditional information transmission) is a very useful quantity in the
study of both quantum and classical separabilities. We also show how to define
entanglement of formation in terms of conditional mutual information. This
paper lays the theoretical foundations for a sequel paper which will present a
computer program that can calculate a decomposition of any separable quantum or
classical state.

</DOC>
<DOC>
<DOCNO> 39676 </DOCNO>
$\Lambda$, $\bar{\Lambda}$ Polarization and Spin Transfer in Lepton


  The flavor and helicity distributions of the $\Lambda$ and $\bar{\Lambda}$
hyperons for both valence and sea quarks are calculated in a perturbative QCD
(pQCD) based model. We relate these quark distributions to the fragmentation
functions of the $\Lambda$ and $\bar{\Lambda}$, and calculate the
$z$-dependence of the longitudinal spin transfer to the $\Lambda$ and
$\bar{\Lambda}$ in lepton deep-inelastic scattering (DIS). It is shown that the
spin transfer to the $\Lambda$ is compatible with the first HERMES results at
DESY and further tests are suggested. We also make predictions for the
$z$-dependence of the $\Lambda$ and $\bar{\Lambda}$ longitudinal polarizations
in neutrino (antineutrino) DIS processes. We investigate the sea contribution
to the fragmentation functions, and we test a possible scenario where sea
quarks in $\Lambda$ (or sea antiquarks in $\bar{\Lambda}$) are negatively
polarized, whereas sea antiquarks in the $\Lambda$ (or sea quarks in
$\bar{\Lambda}$) are positively polarized. The asymmetry of the polarized
fragmentation functions of sea quarks and antiquarks to $\Lambda$ and
$\bar{\Lambda}$ provides a way to understand the different behaviour between
the $\Lambda$ and $\bar{\Lambda}$ spin transfers observed in the recent E665
experiment at FNAL.

</DOC>
<DOC>
<DOCNO> 120297 </DOCNO>
Multiple BeppoSAX Observations of IC 4329A to Probe the Origin of the


  IC 4329A is the brightest known Seyfert galaxy in hard (~2-30 keV) X-rays and
is likely to be representative of Seyfert 1 galaxies as a class. A recent 100
ks BeppoSAX observation (Perola et al. 1999) clearly confirmed the presence of
a warm absorber, a reflection component (R~0.6), and a high-energy cut-off in
the power law at Ec~270 keV. Its richness in spectral features, combined with
its large flux (~1.6 x 10**-10 erg/cm2s between 2-10 keV), make this target
ideal for multiple observations (in particular with BeppoSAX) to search for
spectral variations. Results obtained from 3 follow-up observations (40 ks
each) are presented here. The first and most important goal of this study was
to probe the origin of the Compton reflection component observed in Seyfert
galaxies by monitoring the variability of the reflection continuum and FeK line
in response to primary continuum variations. The second goal was to search for
variability in the high energy cutoff. We obtain however no conclusive results
on any of these issues. In fact, all four observations unfortunately caught the
source at almost the same flux, showing only little, and marginal, spectral
changes between different observations.

</DOC>
<DOC>
<DOCNO> 119115 </DOCNO>
A Proton Synchrotron Blazar Model for Flaring in Markarian~501


  (abr.) The spectral energy distribution (SED) of blazars typically has a
double-humped appearance usually interpreted in terms of synchrotron
self-Compton models. In proton blazar models, the SED is instead explained in
terms of acceleration of protons and subsequent cascading. We discuss a
variation of the Synchrotron Proton Blazar model, first proposed by M\"ucke &
Protheroe (1999), in which the low energy part of the SED is mainly synchrotron
radiation by electrons co-accelerated with protons which produce the high
energy part of the SED mainly asproton synchrotron radiation. Using a Monte
Carlo/numerical technique to simulate the interactions and subsequent cascading
of the accelerated protons, we are able to fit the observed SED of Markarian
501 during the April 1997 flare. We find that the emerging cascade spectra
initiated by gamma-rays from $\pi^0$ decay and by $e^\pm$ from $\mu^\pm$ decay
turn out to be relatively featureless. Synchrotron radiation produced by
$\mu^\pm$ from $\pi^\pm$ decay, and even more importantly by protons, and
subsequent synchrotron-pair cascading, is able to reproduce well the high
energy part of the SED. For this fit we find that synchrotron radiation by
protons dominates the TeV emission, pion photoproduction being less important
with the consequence that we predict a lower neutrino flux than in other proton
blazar models.

</DOC>
<DOC>
<DOCNO> 7677 </DOCNO>
Self-Consistent Tensor Product Variational Approximation for 3D


  We propose a numerical variational method for three-dimensional (3D)
classical lattice models. We construct the variational state as a product of
local tensors, and improve it by use of the corner transfer matrix
renormalization group (CTMRG), which is a variant of the density matrix
renormalization group (DMRG) applied to 2D classical systems. Numerical
efficiency of this approximation is investigated through trial applications to
the 3D Ising model and the 3D 3-state Potts model.

</DOC>
<DOC>
<DOCNO> 69635 </DOCNO>
Neutrino-photon reactions for energies above $m_e$


  We show that neutrino-photon reactions above $m_e$ are dominated by the
reaction $\nu \gamma \to \nu e^+ e^-$. We calculate its cross-section and see
that it is larger by several orders of magnitude than the cross-sections of
other neutrino-photon processes, for energies above $m_e$. We also discuss
potential astrophysical and cosmological consequences.

</DOC>
<DOC>
<DOCNO> 69895 </DOCNO>
Polarization Phenomena by Deuteron Fragmentation into Pions


  The fragmentation of deuterons into pions emitted forward in the kinematic
region forbidden for free nucleon-nucleon collisions is analyzed. The inclusive
relativistic invariant spectrum of pions and the tensor analyzing power T_{20}
are investigated within the framework of an impulse approximation using
different kinds of the deuteron wave function. The influence of P-wave
inclusion in the deuteron wave function is studied, too. The invariant spectrum
is shown to be more sensitive to the amplitude of the $NN \to \pi X$ process
than the tensor analyzing power T_{20}. It is shown that the inclusion of the
non-nucleon degrees of freedom in a deuteron results a satisfactory description
of experimental data about the inclusive pion spectrum and improves the
description of data about T_{20}. According to the experimental data, T_{20}
has the positive sign and very small values, less than 0.2, what contradicts to
the theoretical calculations ignoring these degrees of freedom.

</DOC>
<DOC>
<DOCNO> 122476 </DOCNO>
Multi-wavelength observations of the red giant R Doradus with the MAPPIT


  We present visibility measurements of the nearby Mira-like star R Doradus
taken over a wide range of wavelengths (650-990 nm). The observations were made
using MAPPIT (Masked APerture-Plane Interference Telescope), an interferometer
operating at the 3.9-m Anglo-Australian Telescope. We used a slit to mask the
telescope aperture and prism to disperse the interference pattern in
wavelength. We observed in R Dor strong decreases in visibility within the TiO
absorption bands. The results are in general agreement with theory but differ
in detail, suggesting that further work is needed to refine the theoretical
models.

</DOC>
<DOC>
<DOCNO> 83291 </DOCNO>
DISCO: An object-oriented system for music composition and sound design


  This paper describes an object-oriented approach to music composition and
sound design. The approach unifies the processes of music making and instrument
building by using similar logic, objects, and procedures. The composition
modules use an abstract representation of musical data, which can be easily
mapped onto different synthesis languages or a traditionally notated score. An
abstract base class is used to derive classes on different time scales. Objects
can be related to act across time scales, as well as across an entire piece,
and relationships between similar objects can replicate traditional music
operations or introduce new ones. The DISCO (Digital Instrument for
Sonification and Composition) system is an open-ended work in progress.

</DOC>
<DOC>
<DOCNO> 118915 </DOCNO>
The lithium isotope ratio in the metal-poor halo star G271-162 from


  A high resolution (R = 110.000), very high S/N (>600) spectrum of the
metal-poor turnoff star G271-162 has been obtained in connection with the
commissioning of UVES at VLT/Kueyen. Using both 1D hydrostatic and 3D
hydrodynamical model atmospheres, the lithium isotope ratio has been estimated
from the LiI 670.8 nm line by means of spectral synthesis. The necessary
stellar line broadening (1D: macroturbulence + rotation, 3D: rotation) has been
determined from unblended KI, CaI and FeI lines. The 3D line profiles agree
very well with the observed profiles, including the characteristic line
asymmetries. Both the 1D and 3D analyses reveal a possible detection of 6Li in
G271-162, 6Li/7Li = 0.02 +-0.01 (one sigma). It is discussed if the smaller
amount of 6Li in G271-162 than in the similar halo star HD84937 could be due to
differences in stellar mass and/or metallicity or whether it may reflect an
intrinsic scatter of the Li isotope ratio in the ISM at a given metallicity.

</DOC>
<DOC>
<DOCNO> 8433 </DOCNO>
Quantum Criticality at the Metal Insulator Transition


  We introduce a new method to analysis the many-body problem with disorder.
The method is an extension of the real space renormalization group based on the
operator product expansion. We consider the problem in the presence of
interaction, large elastic mean free path, and finite temperatures. As a result
scaling is stopped either by temperature or the length scale set by the
diverging many-body length scale (superconductivity). Due to disorder a
superconducting instability might take place at $T_{SC}\to 0$ giving rise to a
metallic phase or $T>T_{SC}$. For repulsive interactions at $T\to 0$ we flow
towards the localized phase which is analized within the diffusive Finkelstein
theory. For finite temperatures with strong repulsive backward interactions and
non-spherical Fermi surfaces characterized by $|\frac{d\ln N(b)}{\ln b}|\ll 1$
one finds a fixed point $(D^*,\Gamma^*_2)$ in the plane $(D,\Gamma_2^{(s)})$.
($D\propto(K_F\ell)^{-1}$ is the disorder coupling constant, $\Gamma_2^{(s)}$
is the particle-hole triplet interaction, $b$ is the length scale and $N(b)$ is
the number of channels.) For weak disorder, $D<D^*$, one obtains a metallic
behavior with the resistance
$\rho(D,\Gamma_2^{(s)},T)=\rho(D,\Gamma_2^{(s)},T)\simeq
\rho^*f(\frac{D-D^*}{D^*}\frac{1}{T^{z\nu_1}})$
($\rho^*=\rho(D^*,\Gamma_2^*,1)$, $z=1$, and $\nu_1>1$) in good agreement with
the experiments.

</DOC>
<DOC>
<DOCNO> 151435 </DOCNO>
The transformations of the electromagnetic potentials under translations


  I consider infinitesimal translations $x'^{\alpha}=x^{\alpha}+\delta
x^{\alpha}$ and demand that Noether's approach gives a symmetric
electromagnetic energy-momentum tensor as it is required for gravitational
sources. This argument determines the transformations of the electromagnetic
potentials under infinitesimal translations to be $A'_{\gamma} (x') =
A_{\gamma}(x)+\partial_{\gamma} [\delta x_{\beta} A^{\beta}(x)]$, which differs
from the usually assumed invariance $A'_{\gamma} (x') = A_{\gamma}(x)$, by the
gauge transformation $\partial_{\gamma} [\delta x_{\beta} A^{\beta}(x)]$.

</DOC>
<DOC>
<DOCNO> 72319 </DOCNO>
J/Psi suppression in colliding nuclei: statistical model analysis


  We consider the $J/\Psi$ suppression at a high energy heavy ion collision. An
ideal gas of massive hadrons in thermal and chemical equilibrium is formed in
the central region. The finite-size gas expands longitudinally in accordance
with Bjorken law. The transverse expansion in a form of the rarefaction wave is
taken into account. We show that $J/\Psi$ suppression in such an environment,
when combined with the disintegration in nuclear matter, gives correct
evaluation of NA38 and NA50 data in a broad range of initial energy densities.

</DOC>
<DOC>
<DOCNO> 71786 </DOCNO>
Trilinear Neutral Gauge Boson Couplings


  We study the CP even trilinear neutral gauge boson vertices at one-loop in
the context of the Standard Model and the Minimal Supersymmetric Standard
Model, assuming two of the vector bosons are on-shell. We also study the
changes in the form-factors when these two bosons are off-shell.

</DOC>
<DOC>
<DOCNO> 69281 </DOCNO>
Dynamical growth of the hadron bubbles during the quark-hadron phase


  The rate of dynamical growth of the hadron bubbles in a supercooled baryon
free quark-gluon plasma, is evaluated by solving the equations of relativistic
fluid dynamics in all regions. For a non-viscous plasma, this dynamical growth
rate is found to depend only on the range of correlation $\xi$ of order
parameter fluctuation, and the radius $R$ of the critical hadron bubble, the
two length scales relevant for the description of the critical phenomena.
Further, it is shown that the dynamical prefactor acquires an additive
component when the medium becomes viscous. Interestingly, under certain
reasonable assumption for the velocity of the sound in the medium around the
saddle configuration, the viscous and the non-viscous parts of the prefactor
are found to be similar to the results obtained by Csernai-Kapusta and
Ruggeri-Friedman (for the case of zero viscosity) respectively.

</DOC>
<DOC>
<DOCNO> 117533 </DOCNO>
H_3^(2+) molecular ion in a strong magnetic field: a triangular


  The bound state in the system of three protons and an electron (pppe) under a
homogeneous strong magnetic field where the protons are situated in the
vertices of an equilateral triangle perpendicular to the magnetic field lines
is found. It is shown that for magnetic fields B = 10^11 - 4.414x10^13 G the
potential energy curves as a function of the internuclear distance R have an
explicit minimum. For all magnetic fields studied, the binding energy of the
triangular configuration is less than the binding energy of the linear parallel
configuration (A. Turbiner et al. JETP Lett. 69, p. 844). In the contrary to
the linear case, the binding energy decreases with a magnetic field growth,
while the equilibrium internuclear distance slowly increases.

</DOC>
<DOC>
<DOCNO> 8793 </DOCNO>
Short Coherence Length Superconductivity: A Generalization of BCS Theory


  On the basis of the observed short coherence lengths in the cuprates we argue
that a BCS-Bose-Einstein condensation (BEC) crossover approach is an
appropriate starting point for correcting the mean field approach of BCS and,
thereby, for addressing pseudogap phenomena in these materials. Our version of
the BCS-BEC approach is based on a particular Greens' function decoupling
scheme which should be differentiated from others in the literature, and which
yields (i) the Leggett crossover ground state (for all coupling constants g, at
T=0) and (ii) BCS theory (for all $ T \leq T_c$ over a range of small g). In
this paper we provide a simple physical picture of the pseudogap phase above
and below $T_c$, and review the quantitative and qualitative implications of
this theory, which, for the most part have been published in a series of recent
papers.

</DOC>
<DOC>
<DOCNO> 68934 </DOCNO>
Power-law inflation with a nonminimally coupled scalar field


  We consider the dynamics of power-law inflation with a nonminimally coupled
scalar field $\phi$. It is well known that multiple scalar fields with
exponential potentials $V(\phi)=V_0 {\rm exp}(-\sqrt{16\pi/p m_{\rm pl}^2}
\phi)$ lead to an inflationary solution even if the each scalar field is not
capable to sustain inflation. In this paper, we show that inflation can be
assisted even in the one-field case by the effect of nonminimal coupling. When
$\xi$ is positive, since an effective potential which arises by a conformal
transformation becomes flatter compared with the case of $\xi=0$ for $\phi>0$,
we have an inflationary solution even when the universe evolves as
non-inflationary in the minimally coupled case. For the negative $\xi$, the
assisted inflation can take place when $\phi$ evolves in the region of $\phi<0$
\.

</DOC>
<DOC>
<DOCNO> 70089 </DOCNO>
Noncommutative Compactifications of Type I Strings on Tori with Magnetic


  We construct six- and four-dimensional toroidal compactifications of the Type
I string with magnetic flux on the D-branes. The open strings in this
background probe a noncommutative internal geometry. Phenomenologically
appealing features such as chiral fermions and supersymmetry breaking in the
gauge sector are naturally realized by these vacua. We investigate the spectra
of such noncommutative string compactifications and in a bottom-up approach
discuss the possibility to obtain the standard or some GUT like model.

</DOC>
<DOC>
<DOCNO> 39987 </DOCNO>
The Simplest Resonant Spin--Flavour Solution to the Solar Neutrino


  We re-analyse the resonant spin-flavour (RSF) solutions to the solar neutrino
problem in the framework of analytic solutions to the solar
magneto-hydrodynamics (MHD) equations. By substantially eliminating the
arbitrariness associated to the magnetic field profile due to both mathematical
consistency and physical requirements we propose the simplest scheme (MHD-RSF,
for short) for solar neutrino conversion using realistic static MHD solutions.
Using such effective two-parameter scheme we perform the first global fit of
the recent solar neutrino data, including event rates as well as zenith angle
distributions and recoil electron spectra induced by solar neutrino
interactions in Superkamiokande. We compare quantitatively our simplest MHD-RSF
fit with vacuum oscillation (VAC) and MSW-type (SMA, LMA and LOW) solutions to
the solar neutrino problem using a common well-calibrated theoretical
calculation and fit procedure. We find our MHD-RSF fit to be somewhat better
than those obtained for the favored neutrino oscillation solutions, though not
in a statistically significant way. We briefly discuss the prospects to
disentangle our MHD-RSF scenario at future solar neutrino experiments, giving
some predictions for the SNO experiment.

</DOC>
<DOC>
<DOCNO> 69339 </DOCNO>
Photon-Photon Interaction in a Photon Gas


  Using the effective Lagrangian for the low energy photon-photon interaction
the lowest order photon self energy at finite temperature and in
non-equilibrium is calculated within the real time formalism. The Debye mass,
the dispersion relation, the dielectric tensor, and the velocity of light
following from the photon self energy are discussed. As an application we
consider the interaction of photons with the cosmic microwave background
radiation.

</DOC>
<DOC>
<DOCNO> 85422 </DOCNO>
New properties of Cauchy and event horizons


  We present several recent results concerning Cauchy and event horizons. In
the first part of the paper we review the differentiablity properties of the
Cauchy and the event horizons. In the second part we discuss compact Cauchy
horizons and summarize their main properties.

</DOC>
<DOC>
<DOCNO> 70572 </DOCNO>
Non-perturbative calculations of a global U(1) theory at finite density


  We use an optimised hopping parameter expansion for the free energy (linear
delta expansion) to study the phase transitions at finite temperature and
finite charge density in a global U(1) scalar Higgs sector on the lattice at
large lattice couplings. We are able to plot out phase diagrams in lattice
parameter space and find that the standard second-order phase transition with
temperature at zero chemical potential becomes first order as the chemical
potential increases.

</DOC>
<DOC>
<DOCNO> 69322 </DOCNO>
Properties of the Langevin and Fokker-Planck equations for scalar fields


  I consider several Langevin and Fokker-Planck classes of dynamics for scalar
field theories in contact with a thermal bath at temperature T. These models
have been applied recently in the numerical description of the dynamics of
second order phase transitions and associated topological defect formation as
well as in other studies of these critical phenomena. Closed form solutions of
the Fokker-Planck equation are given for the harmonic potential and a dynamical
mean-field approximation is developed. These methods allow for an analytical
discussion of the behavior of the theories in several circumstances of interest
such as critical slowing down at a second order transition and the development
of spinodal instabilities. These insights allow for a more detailed
understanding of several numerical studies in the literature.

</DOC>
<DOC>
<DOCNO> 101712 </DOCNO>
On properties of theories which preclude the existence of universal


  In this paper we investigate some properties of first order theories which
prevent them from having universal models under certain cardinal arithmetic
assumptions. Our results give a new syntactical condition, oak property, which
is a sufficient condition for a theory not to have universal models in
cardinality lambda when certain cardinal arithmetic assumptions implying the
failure of GCH (and close to the failure of SCH) hold.

</DOC>
<DOC>
<DOCNO> 101116 </DOCNO>
Global existence for wave maps with torsion


  Wave maps (i.e. nonlinear sigma models) with torsion are considered in 2+1
dimensions. Global existence of smooth solutions to the Cauchy problem is
proven for certain reductions under a translation group action: invariant wave
maps into general targets, and equivariant wave maps into Lie group targets. In
the case of Lie group targets (i.e. chiral models), a geometrical
characterization of invariant and equivariant wave maps is given in terms of a
formulation using frames.

</DOC>
<DOC>
<DOCNO> 9675 </DOCNO>
Charge ordering in the TMTTF family of molecular conductors


  Using one- and two-dimensional NMR spectroscopy applied to $^{13}$C
spin-labeled (TMTTF)$_2$AsF$_6$ and (TMTTF)$_2$PF$_6$, we demonstrate the
existence of an intermediate charge-ordered phase in the TMTTF family of
charge-transfer salts. At ambient temperature, the spectra are characteristic
of nuclei in equivalent environments, or molecules. Below a continuous
charge-ordering transition temperature T$_{co}$, the spectra are explained by
assuming there are two inequivalent molecules with unequal electron densities.
The absence of an associated magnetic anomaly indicates only the charge degrees
of freedom are involved and the lack of evidence for a structural anomaly
suggests that charge/lattice coupling is too weak to drive the transition.

</DOC>
<DOC>
<DOCNO> 178571 </DOCNO>
The Half-Life and the Nuclear Matrix Element of the $2\nu\beta\beta$


  We apply the shell-model wave-functions of $^{76}Ge$ to calculate the nuclear
matrix elements and the half-life of the $2\nu\beta\beta$ decay in $^{76}Ge$.
Our result is comparable to the recent observed $2\nu\beta\beta$-decay
half-life of $^{76}Ge$. Furthemore it provides the upper limit of the effective
neutrino mass is about 0.4 eV from the recent experimental data of the
$0\nu\beta\beta$-decay half-life.

</DOC>
<DOC>
<DOCNO> 39777 </DOCNO>
A Review of Bs Mixing: Past, Present and Future


  We review the experimental status of Bs mixing. After a brief historical
overview, current studies of the time dependence of Bs oscillations are
described, with an emphasis on the different experimental techniques used by
the ALEPH, CDF, DELPHI, OPAL, and SLD Collaborations. To conclude, the outlook
for future experiments is presented.

</DOC>
<DOC>
<DOCNO> 120089 </DOCNO>
Ultra High Energy Cosmic Rays: propagation in the Galaxy and anisotropy


  We considered propagation of Ultra High Energy Cosmic Rays (UHECR) through
the galaxy. We investigated models with sources of UHECR distributed in the
same way as Cold Dark Matter (CDM) in a self-consistent way, taking into
account both extra-galactic and Galactic contributions. Using a very simple toy
model of galactic magnetic field we showed that in the case of galactic origin
of UHECRs the anisotropy can reach considerable values. In the case of
extragalactic UHECRs origin the anisotropy appears to be non-vanishing only for
electron and photon components due to synchrotron losses, but it hardly can be
reassured. The reason is an extremely low flux of UHE electrons and a too low
level of gamma-ray anisotropy.

</DOC>
<DOC>
<DOCNO> 120983 </DOCNO>
A Test for the Nature of the Type Ia Supernova Explosion Mechanism


  Currently popular models for Type Ia supernovae (SNe Ia) fall into two
general classes. The first comprises explosions of nearly pure carbon/oxygen
(C/O) white dwarfs at the Chandrasekhar limit which ignite near their centers.
The second consists of lower-mass C/O cores which are ignited by the detonation
of an accreted surface helium layer. Explosions of the latter type produce
copious Fe, Co and Ni K-alpha emission from 56Ni and 56Co decay in the
detonated surface layers, emission which is much weaker from Chandrasekhar-mass
models. The presence of this emission provides a simple and unambiguous
discriminant between these two models for SNe Ia. Both mechanisms may produce
0.1-0.6 solar masses of 56Ni, making them bright gamma-ray line emitters. The
time to maximum brightness of 56Ni decay lines is distinctly shorter in the
sub-Chandrasekhar mass class of model (approximately 15 days) than in the
Chandrasekhar mass model (approximately 30 days), making gamma-ray line
evolution another direct test of the explosion mechanism. It should just be
possible to detect K-shell emission from a sub-Chandrasekhar explosion from SNe
Ia as far away as the Virgo cluster with the XMM Observatory. A 1 to 2 square
meter X-ray telescope such as the proposed Con-X Observatory could observe
K-alpha emission from sub-Chandrasekhar mass SNe Ia in the Virgo cluster,
providing not just a detection, but high-accuracy flux and kinematic
information.

</DOC>
<DOC>
<DOCNO> 8763 </DOCNO>
Spontaneous magnetic moments in YBCO thin films


  We have observed spontaneous magnetic moments with random signs in c-axis
oriented thin films of the high-Tc cuprate superconductor YBCO, imaged with a
scanning SQUID microscope. These moments arise when the samples become
superconducting, and appear to be associated with non-ferromagnetic defects in
the films. In contrast with granular high-Tc samples, which also show
spontaneous magnetization with random signs, these samples shield
diamagnetically.

</DOC>
<DOC>
<DOCNO> 121366 </DOCNO>
Weighing 40 X-ray Luminous Clusters of Galaxies with Weak Gravitational


  Deep two-color imaging of 40 clusters of galaxies with the NOT and the
University of Hawaii 2.24-m telescope is used to measure the weak gravitational
shear acting on faint background galaxies. From this, maps of the projected
cluster mass distribution are constructed, and the cluster masses are measured
within circular apertures of up to ~3 Mpc/h. The results are used to derive the
cluster mass function at z~0.2. The average mass-to-light ratio of the clusters
indicate a low-density Universe with Omega_0 around 0.25. Additional mass
concentrations are found along the lines of sight to the clusters, some of
which are most likely associated with clusters at z > 0.5. In addition, the
data are used to measure weak gravitational lensing due to large-scale
structures along the line of sight. The future prospects for this kind of
research with the NOT are briefly discussed.

</DOC>
<DOC>
<DOCNO> 101351 </DOCNO>
Non-standard Construction of Hamiltonian Structures and of the


  Examples of non-standard construction of Hamiltonian structures for dynamical
systems and the respective Hamilton-Jacobi (H-J) equations, without using
Lagrangians, are presented. Alternative H-J equations for Euler top are
explicitly exhibited and solved. We demonstrate that some stability criterion,
relating the slope of a Casimir function parametrized by the Lagrange
multiplier to critical point type, depends on the used Hamiltonian structure
and it is inadequate for this reason.

</DOC>
<DOC>
<DOCNO> 100099 </DOCNO>
Normalisation des op\'erateurs d'entrelacement et r\'eductibilit\'e des


  On montre comment les conjectures d'Arthur permettent de calculer les points
de r\'eductibilit\'e pour les induites de cuspidales des groupes classiques.
Les conjectures d'Arthur utilis\'ees portent sur l'existence d'un rel\`evement
faible des repr\'esentations automorphes cuspidales d'un groupe classique vers
un groupe lin\'eaire convenable. Et les points de r\'eductibilit\'es sont
decrits en terme de la g\'eom\'etrie des orbites unipotentes des groupe dual.
On en d\'eduit des r\'esultats sur la normalisation des operateurs
d'entrelacement.
  We show how the global conjectures of Arthur allow us to calculate the
points of irreducibility for representations induced from cuspidal
representations of classical groups. The conjectures of Arthur used are
concerned with the existence of weak liftings of automorphic representations
from classical groups to suitable linear ones. And the points of
irreducibility are described in terms of the geometry of unipotent orbits on
the dual group. We deduce certain results about the normalization of
intertwining operators.

</DOC>
<DOC>
<DOCNO> 39658 </DOCNO>
Seesaw mechanism and the neutrino mass matrix


  The seesaw mechanism of neutrino mass generation is analysed under the
following assumptions: (1) minimal seesaw with no Higgs triplets, (2)
hierarchical Dirac masses of neutrinos, (3) large lepton mixing primarily or
solely due to the mixing in the right-handed neutrino sector, and (4) unrelated
Dirac and Majorana sectors of neutrino masses. It is shown that large mixing
governing the dominant channel of the atmospheric neutrino oscillations can be
naturally obtained and that this constrained seesaw mechanism favours the
normal mass hierarchy for the light neutrinos leading to a small $U_{e3}$ entry
of the lepton mixing matrix and a mass scale of the lightest right handed
neutrino $M\simeq 10^{10} - 10^{11}$ GeV. Any of the three main neutrino
oscillation solutions to the solar neutrino problem can be accommodated. The
inverted mass hierarchy and quasi-degeneracy of neutrinos are disfavoured in
our scheme.

</DOC>
<DOC>
<DOCNO> 71252 </DOCNO>
Instanton propagator and instanton induced processes in scalar model


  The propagator in the instanton background in the $(- \lambda \phi^{4})$
scalar model in four dimensions is studied.Leading and sub-leading terms of its
asymptotics for large momenta and its on-shell double residue are calculated
analytically. These results are applied to the analysis of the initial-state
and initial-final-state corrections and the calculation of the next-to-leading
(propagator) correction to the exponent of the cross section of instanton
induced multiparticle scattering processes.

</DOC>
<DOC>
<DOCNO> 122995 </DOCNO>
tau Boo b: Not so bright, but just as heavy


  We present new results derived from high-resolution optical spectra of the
tau Boo system, secured in March-May 2000. The results do not show the same
feature reported by Cameron et al (1999) as a candidate reflected-light
signature from the planet. Together with earlier results from the 1998 and 1999
seasons, the new data yield a 99.9 percent upper limit on the opposition
planet/star flux ratio epsilon<3.5E-5 between 387.4 and 586.3 nm, a factor 3
deeper than the upper limit of Charbonneau et al (1999). For an assumed planet
radius Rp= 1.2 RJup, the upper limit on the mean geometric albedo is p < 0.22,
40 percent that of Jupiter. We find new evidence that the star's rotation is
synchronised with the planet's orbital motion. Using a Monte Carlo analysis we
infer that the planet's mass must lie in the range 5.5 to 10 times the mass of
Jupiter.

</DOC>
<DOC>
<DOCNO> 100978 </DOCNO>
Regular basis and R-matrices for the su(n)_k Knizhnik-Zamolodchikov


  Dynamical R-matrix relations are derived for the group-valued chiral vertex
operators in the SU(n) WZNW model from the KZ equation for a general four-point
function including two step operators. They fit the exchange relations for the
U_q(sl_n) covariant quantum matrix derived previously by solving the dynamical
Yang-Baxter equation. As a byproduct, we extend the regular basis introduced
earlier for SU(2) chiral fields to SU(n) step operators and display the
corresponding triangular matrix representation of the braid group.

</DOC>
<DOC>
<DOCNO> 12797 </DOCNO>
Crystal structures and freezing of dipolar fluids


  We investigate the crystal structure of classical systems of spherical
particles with an embedded point dipole at T=0. The ferroelectric ground state
energy is calculated using generalizations of the Ewald summation technique.
Due to the reduced symmetry compared to the nonpolar case the crystals are
never strictly cubic. For the Stockmayer (i.e., Lennard-Jones plus dipolar)
interaction three phases are found upon increasing the dipole moment:
hexagonal, body-centered orthorhombic, and body-centered tetragonal. An even
richer phase diagram arises for dipolar soft spheres with a purely repulsive
inverse power law potential $\sim r^{-n}$. A crossover between qualitatively
different sequences of phases occurs near the exponent $n=12$. The results are
applicable to electro- and magnetorheological fluids. In addition to the exact
ground state analysis we study freezing of the Stockmayer fluid by
density-functional theory.

</DOC>
<DOC>
<DOCNO> 14143 </DOCNO>
Correlation induced phonon softening in low density coupled bilayer


  We predict a possible phonon softening instability in strongly correlated
coupled semiconductor bilayer systems. By studying the plasmon-phonon coupling
in coupled bilayer structures, we find that the renormalized acoustic phonon
frequency may be softened at a finite wave vector due to many-body local field
corrections, particularly in low density systems where correlation effects are
strong. We discuss experimental possibilities to search for this predicted
phonon softening phenomenon.

</DOC>
<DOC>
<DOCNO> 69354 </DOCNO>
Neutrino Masses and Mixing from Bilinear R-Parity Violation


  Neutrino masses and mixing are generated in a supersymmetric standard model
when R-parity is violated in bilinear mass terms. The mixing matrix among the
neutrinos takes a restrictive form if the lepton flavor universality holds in
the R-parity violating soft masses. It turns out that only the small angle MSW
solution to the solar neutrino problem is consistent with the result of the
CHOOZ experiment and the atmospheric neutrino data.

</DOC>
<DOC>
<DOCNO> 117070 </DOCNO>
Bayesian Blocks: Divide and Conquer, MCMC, and Cell Coalescence


  Identification of local structure in intensive data -- such as time series,
images, and higher dimensional processes -- is an important problem in
astronomy. Since the data are typically generated by an inhomogeneous Poisson
process, an appropriate model is one that partitions the data space into cells,
each of which is described by a homogeneous (constant event rate) Poisson
process. It is key that the sizes and locations of the cells are determined by
the data, and are not predefined or even constrained to be evenly spaced. For
one-dimensional time series, the method amounts to Bayesian changepoint
detection. Three approaches to solving the multiple changepoint problem are
sketched, based on: (1) divide and conquer with single changepoints, (2)
maximum posterior for the number of changepoints, and (3) cell coalescence. The
last method starts from the Voronoi tessellation of the data, and thus should
easily generalize to spaces of higher dimension.

</DOC>
<DOC>
<DOCNO> 118328 </DOCNO>
Multiwavelength observations of Mkn 501 during the 1997 high state


  During the observation period 1997, the nearby Blazar Mkn 501 showed
extremely strong emission and high variability. We examine multiwavelength
aspects of this event using radio, optical, soft and hard X-ray and TeV data.
We concentrate on the medium-timescale variability of the broadband spectra,
averaged over weekly intervals.
  We confirm the previously found correlation between soft and hard X-ray
emission and the emission at TeV energies, while the source shows only minor
variability at radio and optical wavelengths. The non-linear correlation
between hard X-ray and TeV fluxes is consistent with a simple analytic estimate
based on an SSC model in which Klein-Nishina effects are important for the
highest-energy electrons in the jet, and flux variations are caused by
variations of the electron density and/or the spectral index of the electron
injection spectrum.
  The time-averaged spectra are fitted with a Synchrotron Self-Compton (SSC)
dominated leptonic jet model, using the full Klein-Nishina cross section and
following the self-consistent evolution of relativistic particles along the
jet, accounting for gamma-gamma absorption and pair production within the
source as well as due to the intergalactic infrared background radiation. The
contribution from external inverse-Compton scattering is tightly constrained by
the low maximum EGRET flux and found to be negligible at TeV energies. We find
that high levels of the X-ray and TeV fluxes can be explained by a hardening of
the energy spectra of electrons injected at the base of the jet, in remarkable
contrast to the trend found for gamma-ray flares of the flat-spectrum radio
quasar PKS 0528+134.

</DOC>
<DOC>
<DOCNO> 12591 </DOCNO>
Mixed States of Composite Fermions Carrying Two and Four Vortices


  There now exists preliminary experimental evidence for some fractions, such
as $\nu$ = 4/11 and 5/13, that do not belong to any of the sequences
$\nu=n/(2pn\pm 1)$, $p$ and $n$ being integers. We propose that these states
are mixed states of composite fermions of different flavors, for example,
composite fermions carrying two and four vortices. We also obtain an estimate
of the lowest-excitation dispersion curve as well as the transport gap; the
gaps for 4/11 are smaller than those for 1/3 by approximately a factor of 50.

</DOC>
<DOC>
<DOCNO> 70946 </DOCNO>
$J/\psi$ suppression: gluonic dissociation {\em vs.} colour screening


  We evaluate the suppression of $J/\psi$ production in an equilibrating quark
gluon plasma for two competing mechanisms: Debye screening of colour
interaction and dissociation due to energetic gluons. Results are obtained for
$S+S$ and $Au+Au$ collisions at RHIC and LHC energies. At RHIC energies the
gluonic dissociation of the charmonium is found to be equally important for
both the systems while the screening of the interaction plays a significant
role only for the larger systems.
 At LHC energies the Debye mechanism is found to dominate for both the systems.
While considering the suppression of directly produced $\Upsilon$ at LHC
energies, we find that only the gluonic dissociation mechanism comes into play
for the initial conditions taken from the self screened parton cascade model in
these studies. Thus we find that a systematic study of quarkonium suppression
for systems of varying dimensions can help identify the source and the extent
of the suppression.

</DOC>
<DOC>
<DOCNO> 119282 </DOCNO>
Time-series Spectroscopy of Pulsating sdB Stars: PG1605+072


  We report the detection of velocity variations in the pulsating sdB star, PG
1605+072. Oscillations are detected at the same frequencies found from
photometry and have amplitudes of up to 14 km/s for H$\beta$. The strongest
oscillation found in previous photometric observations is not evident in our
spectroscopy or photometry, and may be absent due to beating of closely spaced
modes. Phase differences between spectroscopy and B magnitude photometry imply
that maximum brightness occurs not long after maximum radius. We have also
found evidence of variation in the observed amplitudes of five Balmer lines,
with a decrease in amplitude of the strongest mode blueward from H$\beta$. This
effect is not expected and a longer time-series will be needed to clarify it.

</DOC>
<DOC>
<DOCNO> 119119 </DOCNO>
A microcopic derivation of Einstein's Special Relativity: simple


  The starting point of Special Relativity$^1$ is the Lorentz transformation,
which in essence describes the lack of absolute measurements of space and time.
These effects came about when one applies the Second Relativity Postulate to
inertial observers. Here I demonstrate that there is a very elegant way of
explaining how exactly nature enforces Special Relativity, which compels us to
conclude that Einstein's theory necessitated quantization of space and time.
The model proposes that microscopically the structure of space-time is
analogous to a crystal which consists of lattice points or `tickmarks' (for
measurements) connected by identical `elastic springs'. When at rest the
`springs' are at their natural states. When set in motion, however, the lattice
vibrates in a manner described by Einstein's theory of the heat capacity of
solids, with consequent widening of the `tickmarks' because the
root-mean-square separation now increases. I associate a vibration temperature
$T$ with the speed of motion $v$ via the fundamental postulate of this theory,
viz. the relation $\frac{v^2}{c^2} = e^{-\frac{\epsilon}{kT}}$ where $\epsilon$
is a quantum of energy of the lattice harmonic oscillator. A moving observer
who measures distances and time intervals with such a vibrating lattice obtains
results which are precisely those given by the Lorentz transformation. Apart
from its obvious beauty, this approach provides many new prospects in
understanding space and time. For example, an consequence of the model is that
space-time, like mass, has an equivalence with energy.

</DOC>
<DOC>
<DOCNO> 170580 </DOCNO>
Improving the Fidelity of Quantum Cloning by Fast Cycling away the


  The fidelity of quantum cloning is very often limited by the accompanying
unwanted transitions. We show how the fidelity can be improved by using a
coherent field to cycle away the unwanted transitions. We demonstrate this
explicitly in the context of the model of Simon {\it et al.} [J. Mod. Opt. {\bf
47}, 233 (2000) ; Phys. Rev. Lett. {\bf 84}, 2993 (2000)]. We also investigate
the effects of the number of atoms on the quality of quantum cloning. We show
that the universality of the scheme can be maintained by choosing the cycling
field according to the input state of the qubit.

</DOC>
<DOC>
<DOCNO> 150452 </DOCNO>
On a possible quantum limit for the stabilization of moduli in


  I consider the implications for brane-world scenarios of the rather robust
quantum-gravity expectation that there should be a quantum minimum limit on the
uncertainty of all physical length scales. In order to illustrate the possible
significance of this issue, I observe that, according to a plausible estimate,
the quantum limit on the length scales that characterize the bulk geometry
could affect severely the phenomenology of a recently-proposed brane-world
scenario.

</DOC>
<DOC>
<DOCNO> 69252 </DOCNO>
Small x, Saturation and the High Energy Limit of QCD


  The high energy limit of QCD is controlled by the small-$x$ part of a hadron
wavefunction. We argue that this part is universal to all hadrons and is
composed of a new form of matter: a Colored Glass Condensate. This matter is
weakly interacting at very small $x$, but is non-perturbative because of the
highly occupied boson states which compose the condensate. Such a matter might
be studied in high energy lepton-hadron or hadron-hadron interactions.

</DOC>
<DOC>
<DOCNO> 116772 </DOCNO>
Scaling-violation phenomena and fractality in the human posture control


  By analyzing the movements of quiet standing persons by means of wavelet
statistics, we observe multiple scaling regions in the underlying body
dynamics. The use of the wavelet-variance function opens the possibility to
relate scaling violations to different modes of posture control. We show that
scaling behavior becomes close to perfect, when correctional movements are
dominated by the vestibular system.

</DOC>
<DOC>
<DOCNO> 85375 </DOCNO>
Equivalence between the ADM-Hamiltonian and the harmonic-coordinates


  The third post-Newtonian approximation to the general relativistic dynamics
of two point-mass systems has been recently derived by two independent groups,
using different approaches, and different coordinate systems. By explicitly
exhibiting the map between the variables used in the two approaches we prove
their physical equivalence. Our map allows one to transfer all the known
results of the Arnowitt-Deser-Misner (ADM) approach to the harmonic-coordinates
one: in particular, it gives the value of the harmonic-coordinates Lagrangian,
and the expression of the ten conserved quantities associated to global
Poincar\'e invariance.

</DOC>
<DOC>
<DOCNO> 13916 </DOCNO>
Measurement of the hydrodynamic forces between two polymer-coated


  The hydrodynamic forces between Brownian spheres are determined from a
measurement of the correlated thermal fluctuations in particle position using a
new method, two-particle cross-correlation spectroscopy (TCS). A pair of 1.3 um
diameter polymer-coated poly(methyl methacrylate) were held at separations of
between 2 um and 20 um using optical traps. The mobility tensor is determined
directly from the statistically-averaged Brownian fluctuations of the two
spheres. The observed distance dependence of the mobility tensor is in
quantitative agreement with low-Reynolds number calculations.

</DOC>
<DOC>
<DOCNO> 102577 </DOCNO>
Noncommutative scalar solitons: existence and nonexistence


  We study the variational equations for solitons in noncommutative scalar
field theories in an even number of spatial dimensions. We prove the existence
of spherically symmetric solutions for a sufficiently large noncommutativity
parameter $\theta$ and we prove the absence of spherically symmetric solutions
for small $\theta$.

</DOC>
<DOC>
<DOCNO> 151415 </DOCNO>
Information transfer via the phase: A local model of


  Conventionally, one interprets the correlations observed in
Einstein-Podolsky-Rosen experiments by Bell's inequalities and quantum
nonlocality. We show, in this paper, that identical correlations arise, if the
phase relations of electromagnetic fields are considered. In particular, we
proceed from an analysis of a one-photon model. The correlation probability in
this case contains a phase relation cos(b - a) between the two settings. In the
two photon model the phases of the photon's electromagnetic fields are related
at the origin. It is shown that this relation can be translated into a
linearity requirement for electromagnetic fields between the two polarizers.
Along these lines we compute the correlation integral with an expression
conserving linearity. This expression, as shown, correctly describes the
measured values. It seems thus that quantum nonlocality can be seen as a
combination of boundary conditions on possible electromagnetic fields between
the polarizers and a relation of the electromagnetic fields of the two photons
via a phase. We expect the same feature to arise in every experiment, where
joint probabilities of separate polarization measurements are determined.

</DOC>
<DOC>
<DOCNO> 170455 </DOCNO>
Neel state of antiferromagnet as a result of a local measurement in the


  Single-site measurement in a distributed macroscopic antiferromagnet is
considered; we show that it can create antiferromagnetic sublattices at
macroscopic scale. We demonstrate that the result of measurement depends on the
symmetry of the ground state: for the easy-axis case the Neel state is formed,
while for the easy-plane case unusual ``fan'' sublattices appear with unbroken
rotational symmetry, and a decoherence wave is generated. For the latter case,
a macroscopically large number of measurements is needed to pin down the
orientation of the sublattices, in spite of the high degeneracy of the ground
state. We note that the type of the final state and the appearance of the
decoherence wave are governed by the degree of entanglement of spins in the
system.

</DOC>
<DOC>
<DOCNO> 12112 </DOCNO>
Edge Singularity for the Optically Induced Kondo Effect in a Quantum Dot


  We analyze the optically induced Kondo effect in the absorption spectrum for
a quantum dot with an even number of electrons, for which the Kondo effect does
not occur in the ground state. The Kondo exchange couplings generated for
photo-excited states can be either antiferromagnetic or ferromagnetic, which
may result in different types of the edge singularities, depending on the
microscopic parameters of the dot. We discuss critical properties in the
spectrum by using low-energy effective field theory.

</DOC>
<DOC>
<DOCNO> 116737 </DOCNO>
Effects of the August 11, 1999 total solar eclipse as deduced from total


  We present the results derived from measuring fundamental parameters of the
ionospheric response to the August 11, 1999 total solar eclipse. Our study is
based on using the data from about 70 GPS stations located in the neighbourhood
of the eclipse totality phase in Europe. The eclipse period was characterized
by a low level of geomagnetic disturbance (Dst - variation from -10 to -20 nT),
which alleviated significantly the problem of detecting the ionospheric
response to the eclipse. Our analysis revealed a well-defined effect of a
decrease (depression) of the total electron content (TEC) for all GPS stations.
The delay between minimum TEC values with respect to the totality phase near
the eclipse path increased gradually from 4 min in Greenwich longitude (10:40
UT, LT) to 8 min at the longitude 16 degrees (12:09 LT). The depth and duration
of the TEC depression were found to be 0.2-0.3 TECU and 60 min, respectively.
The results obtained in this study are in good agreement with earlier
measurements and theoretical estimates.

</DOC>
<DOC>
<DOCNO> 67789 </DOCNO>
Updated Bounds on Milli-Charged Particles


  We update the bounds on fermions with electric charge $\epsilon e$ and mass
$m_\epsilon$. For $m_\epsilon\lsim m_e$ we find $10^{-15}\lsim\epsilon<1$ is
excluded by laboratory experiments, astrophysics and cosmology. For larger
masses, the limits are less restrictive and depend on $m_\epsilon$. For
milli-charged neutrinos, the limits are stronger, especially if the different
flavors mix as suggested by current experimental evidence.

</DOC>
<DOC>
<DOCNO> 39836 </DOCNO>
Prompt Photon Production and Observation of Deeply Virtual Compton


  Two recent results in ep physics using the ZEUS detector at HERA are
discussed: a measurement of the prompt photon production cross section in
photoproduction, and the first observation of Deeply Virtual Compton Scattering
in DIS.

</DOC>
<DOC>
<DOCNO> 68261 </DOCNO>
Pauli-Villars regularization and discrete light-cone quantization in


  The techniques of Pauli-Villars regularization and discrete light-cone
quantization are combined to analyze Yukawa theory in a single-fermion
truncation. A special form of the Lanczos algorithm is constructed for
diagonalization of the indefinite-metric light-cone Hamiltonian.

</DOC>
<DOC>
<DOCNO> 169928 </DOCNO>
Mixed-state twin observables


  Twin observables, i.e. opposite subsystem observables A+ and A- that are
indistinguishable in measurement in a given mixed or pure state W, are
investigated in detail algebraicly and geometrically. It is shown that there is
a far-reaching correspondence between the detectable (in W) spectral entities
of the two operators. Twin observables are state-dependently quantum-logically
equivalent, and direct subsystem measurement of one of them ipso facto gives
rise to the indirect (i.e. distant) measurement of the other. Existence of
nontrivial twins requires singularity of W. Systems in thermodynamic
equilibrium do not admit subsystem twins. These observables may enable one to
simplify the matrix representing W.

</DOC>
<DOC>
<DOCNO> 169920 </DOCNO>
Decoherence and thermalization dynamics of a quantum oscillator


  We introduce the quantitative measures characterizing the rates of
decoherence and thermalization of quantum systems. We study the time evolution
of these measures in the case of a quantum harmonic oscillator whose relaxation
is described in the framework of the standard master equation, for various
initial states (coherent, `cat', squeezed and number). We establish the
conditions under which the true decoherence measure can be approximated by the
linear entropy $1-{Tr}\hat\rho^2$. We show that at low temperatures and for
highly excited initial states the decoherence process consists of three
distinct stages with quite different time scales. In particular, the `cat'
states preserve 50% of the initial coherence for a long time interval which
increases logarithmically with increase of the initial energy.

</DOC>
<DOC>
<DOCNO> 70264 </DOCNO>
Overview of Grand Unified Models and Their Predictions for Neutrino


  A brief overview of Grand Unified Models is presented with some attention
paid to their predictions for neutrino oscillations. Given the well-known
features of the two non-unified standard models, SM and MSSM, a listing of the
features of classes of unified models is given, where a GUT flavor symmetry
and/or family symmetry are introduced to reduce the number of model parameters.
Some general remarks are then made concerning the type of predictions that
follow for the neutrino masses and mixings.

</DOC>
<DOC>
<DOCNO> 178519 </DOCNO>
Important role of the spin-orbit interaction in forming the 1/2^+


  The structure of the second 0^+ state of ^{10}Be is investigated using a
microscopic $\alpha+\alpha+n+n$ model based on the molecular-orbit (MO) model.
The second 0^+ state, which has dominantly the (1/2^+)^2 configuration, is
shown to have a particularly enlarged $\alpha-\alpha$ structure. The kinetic
energy of the two valence neutrons occupying along the $\alpha-\alpha$ axis is
reduced remarkably due to the strong $\alpha$ clustering and, simultaneously,
the spin-orbit interaction unexpectedly plays important role to make the energy
of this state much lower. The mixing of states with different spin structure is
shown to be important in negative-parity states. The experimentally observed
small-level spacing between 1^- and 2^- (~ 300 keV) is found to be an evidence
of this spin-mixing effect. ^{12}{Be} is also investigated using
$\alpha+\alpha+4n$ model, in which four valence neutrons are considered to
occupy the (3/2^-)^2(1/2^+)^2 configuration. The energy surface of ^{12}Be is
shown to exhibit similar characteristics, that the remarkable $\alpha$
clustering and the contribution of the spin-orbit interaction make the binding
of the state with (3/2^-)^2(1/2^+)^2 configuration properly stronger in
comparison with the closed p-shell (3/2^-)^2(1/2^-)^2 configuration.

</DOC>
<DOC>
<DOCNO> 116538 </DOCNO>
Stochastic Resonance in Neuron Models: Endogenous Stimulation Revisited


  The paradigm of stochastic resonance (SR)---the idea that signal detection
and transmission may benefit from noise---has met with great interest in both
physics and the neurosciences. We investigate here the consequences of reducing
the dynamics of a periodically driven neuron to a renewal process (stimulation
with reset or endogenous stimulation). This greatly simplifies the mathematical
analysis, but we show that stochastic resonance as reported earlier occurs in
this model only as a consequence of the reduced dynamics.

</DOC>
<DOC>
<DOCNO> 174513 </DOCNO>
Instrumentation for and First Results on Nuclear Responses for Supernova


  Our collaboration has set up a focal plane detection system and a focal plane
polarimeter at the large acceptance Big-Bite Spectrometer at AGOR. The detector
systems are equipped with a high performance readout and online data processing
system, which allows polarization transfer and charge transfer measurements at
extreme forward angles with high precision. Preliminary results on GT+ strength
distributions obtained in (d,2He) measurements revealing the fine structure of
the distributions are presented. Their relation to recent calculations of
stellar weak interaction rates is discussed.

</DOC>
<DOC>
<DOCNO> 13629 </DOCNO>
Quantum Correlations in Two-Fermion Systems


  We characterize and classify quantum correlations in two-fermion systems
having 2K single-particle states. For pure states we introduce the Slater
decomposition and rank (in analogy to Schmidt decomposition and rank), i.e. we
decompose the state into a combination of elementary Slater determinants formed
by mutually orthogonal single-particle states. Mixed states can be
characterized by their Slater number which is the minimal Slater rank required
to generate them. For K=2 we give a necessary and sufficient condition for a
state to have a Slater number of 1. We introduce a correlation measure for
mixed states which can be evaluated analytically for K=2. For higher K, we
provide a method of constructing and optimizing Slater number witnesses, i.e.
operators that detect Slater number for some states.

</DOC>
<DOC>
<DOCNO> 151997 </DOCNO>
Stringy Confining Wilson Loops


  The extraction of Wilson loops of confining gauge systems from their SUGRA
(string) duals is reviewed. I start with describing the basic classical setup.
A theorem that determines the classical values of the loops associated with a
generalized background is derived. In particular sufficient conditions for
confining behavior are stated . I then introduce quadratic quantum fluctuations
around the classical configurations. I discuss in details the following models
of confining behavior: (i) Strings in flat space-time, (ii) $AdS_5$ black hole
and its correspondence with pure YM theory in three dimensions. In particular
an attractive Luscher term is shown to be the outcome of the quantum
fluctuations. (iii) Type 0 string model (iv) The Polchinski Strassler $N=1*$
model. In the latter case we show that SUGRA alone is not enough to get the
correct nature of the loops, and only by incorporating the worldvolume
phenomena of the five branes a coherent qualitative picture can be derived.

</DOC>
<DOC>
<DOCNO> 123301 </DOCNO>
Wolf-Rayet stars and GRB connection


  Observed properties of GRBs, WR stars and their CO-cores in the end of
evolution are analyzed. A possible bimodality of the observed GRB energy
distribution ($10^{48}$ erg for GRB9809425; $3\times 10^{51}\div 2\times
10^{54}$ erg for others) is in accord with the bimodal mass distribution of
relativistic objects ($M_{NS}=(1.35\pm 0.15) M_\odot$; $M_{BH}=(4\div 15)
M_\odot$). The peculiarity of SN1998bw can be related to the rotation of the
collapsing CO-core. The expected galactic collapse rate of CO-cores of most
compact WR stars of type WO is $\sim 10^{-5}$ per year, only by one and a half
order of magnitude higher than the GRB rate. The allowance for a gamma-ray
beaming or random outcome of the CO-core collapse due to some instabilities
brings this rate in accordance GRB rate. We argue that WR stars (most probably,
of type WO) can be considered as progenitors of cosmic gamma-ray bursts. Two
types of GRBs are predicted in correspondence with the bimodal mass
distribution of the relativistic objects. Three types of optical afterglows
should appear depending on which CO-core is collapsing: of a single WR star, of
a WR star in a WR+O or a hypothetic WR+(A-M) binary system. We briefly discuss
a model of GRB as a transient phenomenon occurring at early stages of galactic
evolution ($z>1$), when very massive ($M>100 M_\odot$) low-metallicity stars
could form. WR-galaxies can be most probable candidates for GRB host galaxies.

</DOC>
<DOC>
<DOCNO> 123318 </DOCNO>
Effect of an Accretion Disk on the Gravitational Wave Signal from an


  Since black holes can only accrete sub-Keplerian matter, a companion black
hole orbiting on a circular and instantaneously Keplerian orbit around a
central, massive black hole in a galactic Centre will loss angular momentum and
energy to the accreting matter. This loss could be a significant fraction of
the loss due to gravitational wave (GW) emission. The corresponding GW signal
would be modified. We discuss this effects in the light of the modern accretion
disk theory.

</DOC>
<DOC>
<DOCNO> 40117 </DOCNO>
Setting Confidence Belts


  We propose using a Bayes procedure with uniform improper prior to determine
credible belts for the mean of a Poisson distribution in the presence of
background and for the continuous problem of measuring a non-negative quantity
$\theta$ with a normally distributed measurement error. Within the Bayesian
framework, these belts are optimal. The credible limits are then examined from
a frequentist point of view and found to have good frequentist and conditional
frequentist properties.

</DOC>
<DOC>
<DOCNO> 122454 </DOCNO>
The Formation and Evolution of Multiple Star Systems


  Multiple systems play an important role in the evolution of star clusters.
First we discuss several formation mechanisms which depend on the presence of
binaries, either primordial or of dynamical origin. Hierarchical configurations
are often stable over long times and yet may experience evolution of the
internal orbital parameters. We describe an attempt to model the eccentricity
change induced by the outer component using an averaging method, together with
the effects due to tidal dissipation and apsidal motion acting on the inner
binary. This treatment is adopted for systems with high induced eccentricity
which gives rise to some interesting outcomes of significant period shrinkage.

</DOC>
<DOC>
<DOCNO> 71532 </DOCNO>
Dileptons from a Quark Gluon Plasma with Finite Baryon Density


  We investigate the effects of a baryon-antibaryon asymmetry on the spectrum
of dileptons radiating from a quark gluon plasma. We demonstrate the existence
of a new set of processes in this regime. The dilepton production rate from the
corresponding diagrams is shown to be as important as that obtained from the
usual quark-antiquark annihilation.

</DOC>
<DOC>
<DOCNO> 68644 </DOCNO>
Possible Origin of Antimatter Regions in the Baryon Dominated Universe


  We discuss the evolution of U(1) symmetric scalar field at the inflation
epoch with a pseudo Nambu-Goldstone tilt revealing after the end of
exponential expansion of the Universe. The U(1) symmetry is supposed to be
associated with baryon charge. It is shown that quantum fluctuations lead in
natural way to baryon dominated Universe with antibaryon excess regions. The
range of parameters is calculated at which the fraction of Universe occupied by
antimatter and the size of antimatter regions satisfy the observational
constraints, survive to the modern time and lead to effects, accessible to
experimental search for antimatter.

</DOC>
<DOC>
<DOCNO> 150798 </DOCNO>
TASI Lectures on M Theory Phenomenology


  These lectures discuss some of the general issues in developing a
phenomenology for Superstring Theory/M Theory. The focus is on the question:
how might one obtain robust, generic predictions. For example, does the theory
predict low energy supersymmetry breaking? In the course of these explorations,
basics of supersymmetry and supersymmetry breaking, string moduli, cosmological
issues, and other questions are addressed. The notion of approximate moduli and
their possible role plays a central role in the discussion.

</DOC>
<DOC>
<DOCNO> 9728 </DOCNO>
Antiferromagnetic Zigzag Spin Chain in Magnetic Fields at Finite


  We study thermodynamic behaviors of the antiferromagnetic zigzag spin chain
in magnetic fields, using the density-matrix renormalization group method for
the quantum transfer matrix. We focus on the thermodynamics of the system near
the critical fields in the ground-state magnetization process($M$-$H$ curve):
the saturation field, the lower critical field associated with excitation gap,
and the field at the middle-field cusp singularity. We calculate magnetization,
susceptibility and specific heat of the zigzag chain in magnetic fields at
finite temperatures, and then discuss how the calculated quantities reflect the
low-lying excitations of the system related with the critical behaviors in the
$M$-$H$ curve.

</DOC>
<DOC>
<DOCNO> 150980 </DOCNO>
Reply to comment on Casimir energy for spherical boundaries


  It is shown that the recent criticism of Brevik et al. (hep-th/0004041) is in
error.

</DOC>
<DOC>
<DOCNO> 12429 </DOCNO>
Stability of a Vortex in a Rotating Trapped Bose-Einstein Condensate


  We briefly discuss energy, normal modes and dynamics of a vortex in a trapped
Bose-Einstein condensate. Theoretical results are compared with current
experiments.

</DOC>
<DOC>
<DOCNO> 39947 </DOCNO>
Search for Quark-Lepton Compositeness at Tevatron and LHC


  We make a Monte Carlo study on compositeness of first generation quarks and
leptons using the Drell-Yan distribution in the high dielectron mass region at
the Tevatron and LHC energies. The current experimental lower limits on the
compositeness scale, \Lambda, vary from 2.5 to 6.1 TeV. In the present
analysis, we assume that there will be no deviation of the dielectron mass
spectrum from Standard Model prediction at center of mass energy 2 TeV
(Tevatron) and 14 TeV (LHC). We then find that in the LL, RR, RL and LR
chirality channels of the quark-electron currents, it is possible to extend the
lower limits on \Lambda (at 95% {CL}) to a range of 6 to 10 TeV for 2 fb^{-1}
and 9 to 19 TeV for 30 fb^{-1} of integrated luminosity at Tevatron. At LHC,
the corresponding limits extend to a range of 16 to 25 TeV for 10 fb^{-1} and
20 to 36 TeV for 100 fb^{-1} of integrated luminosity.

</DOC>
<DOC>
<DOCNO> 100430 </DOCNO>
Generating-function method for fusion rules


  This is the second of two articles devoted to an exposition of the
generating-function method for computing fusion rules in affine Lie algebras.
The present paper focuses on fusion rules, using the machinery developed for
tensor products in the companion article. Although the Kac-Walton algorithm
provides a method for constructing a fusion generating function from the
corresponding tensor-product generating function, we describe a more powerful
approach which starts by first defining the set of fusion elementary couplings
from a natural extension of the set of tensor-product elementary couplings. A
set of inequalities involving the level are derived from this set using Farkas'
lemma. These inequalities, taken in conjunction with the inequalities defining
the tensor products, define what we call the fusion basis. Given this basis,
the machinery of our previous paper may be applied to construct the fusion
generating function. New generating functions for sp(4) and su(4), together
with a closed form expression for their threshold levels are presented.

</DOC>
<DOC>
<DOCNO> 71254 </DOCNO>
Hadronic centrality dependence in nuclear collisions


  The kaon number density in nucleus+nucleus and p+p reactions is investigated
for the first time as a function of the initial energy density $\epsilon$ and
is found to exhibit a discontinuity around $\epsilon$=1.3 GeV/fm$^3$. This
suggests a higher degree of chemical equilibrium for $\epsilon >$
  1.3 GeV/fm$^3$. It can also be interpreted as reflection of the same
discontinuity, appearing in the chemical freeze out temperature (T) as a
function of $\epsilon$. The $N^{\alpha \sim 1}$ dependence of (u,d,s) hadrons,
whith N the number of participating nucleons, also indicates a high degree of
chemical equilibrium and T saturation, reached at $\epsilon >$1.3 GeV/fm$^3$.
Assuming that the intermediate mass region (IMR) dimuon enhancement seen by
NA50 is due to open charm ($D \bar{D}$), the following observation can be made:
a) Charm is not equilibrated. b) $J/\Psi/D \bar{D}$ suppression -unlike
$J/\Psi/DY$- appears also in S+A collisions, above $\epsilon$ $\sim$1
GeV/fm$^3$. c) Both charm and strangeness show a discontinuity near the same
$\epsilon$. d) $J/\Psi$ could be formed mainly through $c \bar{c}$ coalescence.
e) The enhancement factors of hadrons with u,d,s,c quarks may be connected in a
simple way to the mass gain of these particles if they are produced out of a
quark gluon plasma (QGP). We discuss these results as possible evidence for the
QCD phase transition occuring near $\epsilon \sim $1.3 GeV/fm$^3$.

</DOC>
<DOC>
<DOCNO> 70614 </DOCNO>
Some possibilities for laboratory searches for variations of fundamental


  We consider different options for the search for possible variations of the
fundamental constants. We give a brief overview of the results obtained with
several methods. We discuss their advantages and disadvantages with respect to
simultaneous variations of all constants in both time and space in the range
10^{8}-10^{10} yr. We also suggest a few possibilities for the laboratory
search. Particularly, we propose some experiments with the hyperfine structure
of hydrogen, deuterium and ytterbium-171 and of some atoms with a small
magnetic moment. Other suggestions are for some measurements of the fine
structure associated with the ground state. Special attention is paid to the
interpretation of the hfs measurements in terms of variations of the
fundamental constants.

</DOC>
<DOC>
<DOCNO> 151160 </DOCNO>
Time reparametrization-invariant dynamics of a relativistic string


  The time-reparametrization-invariant dynamics of a relativistic string is
studied in the Dirac generalized Hamiltonian theory by resolving the first
class constraints. The reparametrization-invariant evolution parameter is
identified with the time-like coordinate of the "center of mass" of a string
which is separated from local degrees of freedom by transformations conserving
the group of diffeomorphisms of the generalized Hamiltonian formulation and the
Poincare covariance of local constraints. To identify the "center of mass"
time-like coordinate with the invariant proper time (measured by an observer in
the comoving frame of reference), we apply the Levi-Civita - Shanmugadhasan
canonical transformations which convert the global (mass-shell) constraint into
a new momentum, so that the corresponding gauge is not needed for the
Hamiltonian reduction. The resolving of local constraints leads to an
"equivalent unconstrained system" in the reduced phase space with the
Roehrlich-type Hamiltonian of evolution with respect to the proper time.

</DOC>
<DOC>
<DOCNO> 11734 </DOCNO>
Dynamic critical behavior of disordered 3D Heisenberg ferromagnets


  The influence of a strong disorder on the critical dynamics of 3D Heisenberg
ferromagnet was investigated by high-resolution quasielastic neutron
scattering. A new disorder-induced dynamical critical behavior was found,
characterized by its critical exponent z=2.3. The dynamical scaling function
appeared mainly unaffected by disorder but its description led to a new
parameterization of the Renormalization Group theory, as in the case of pure
Nickel.

</DOC>
<DOC>
<DOCNO> 70867 </DOCNO>
Supersymmetry versus precision experiments revisited


  We study constraints on the Minimal Supersymmetric Standard Model from
electroweak experiments. We find that the light sfermions always make the fit
worse than the Standard Model, while the light chargino generally make the fit
slightly better through the oblique corrections. The best overall fit to the
precision measurements are found when the mass of lighter chargino is about 100
GeV and the SU(2)_L doublet sfermions are all much heavier. We find the slight
improvement of the fit over the SM, where the total \chi^2 of the fit decreases
by about one unit.

</DOC>
<DOC>
<DOCNO> 121168 </DOCNO>
The Lithium Depletion Boundary as a Clock and Thermometer


  We take a critical look at the lithium depletion boundary (LDB) technique
that has recently been used to derive the ages of open clusters. We identify
the sources of experimental and systematic error and show that the probable
errors are larger by approximately a factor two than presently claimed in the
literature. We then use the Pleiades LDB age and photometry in combination with
evolutionary models to define empirical colour-T_eff relations that can be
applied to younger clusters. We find that these relationships DO NOT produce
model isochrones that match the younger cluster data. We propose that this is
due either to systematic problems in the evolutionary models or an age
(gravity) sensitivity in the colour-T_eff relation which is not present in
published atmospheric models.

</DOC>
<DOC>
<DOCNO> 70299 </DOCNO>
Intersections 2000: What's New in Hadron Physics


  Hadron physics is that part of QCD dealing with hadron structure and vacuum
structure, almost all of which is nonperturbative in nature. Some of the open
problems in this field are outlined. We argue that hadron physics is a distinct
subfield, no longer within particle physics, and not at all the same as
classical nuclear physics. We believe that it needs to be better organized, and
that a first step in doing so might be to establish hadron physics as a new
division within the American Physical Society.

</DOC>
<DOC>
<DOCNO> 11582 </DOCNO>
Field theory of avalanche formation


  Self-organizing system is studied whose behavior is governed by field of an
order parameter, a fluctuation amplitude of conjugate field and a couple of
Grassmannian conjugated fields that define the entropy as a control parameter.
Within the framework of self-consistent approach the dependencies of macro- and
microscopic susceptibilities as well as memory and nonergodicity parameters are
determined as a functions of the intensities of thermal and quenched disorders.
Making use of the sandpile model shows that proposed scheme determines the
conditions of avalanches formation in self-organized criticality phenomena.

</DOC>
<DOC>
<DOCNO> 69902 </DOCNO>
Basic Constituents of the Visible and Invisible Matter - A Microscopic


  One of the greatest achievements of twentieth century physics is the
discovery of a very close link between the microcosm and the macrocosm. This
follows from the two basic principles of quantum mechanics and relativity, the
uncertainty principle and the mass energy equivalence, along with the standard
big bang model of cosmology. As we probe deeper into the microcosm we encounter
states of higher mass and energy, which were associated with the early history
of the universe. Thus discovery of the atomic nucleus followed by the nuclear
particles, quarks & gluons and finally the $W$ & $Z$ bosons have recreated in
the laboratory the forms of matter that abounded in the very early universe.
This has helped us to trace back the history of the universe to within a few
picoseconds of its creation. Finally the discovery of the Higgs and
supersymmetric particles will help to solve the mystry of the invisible matter,
which abound throughout the universe today, as relics of that early history.

</DOC>
<DOC>
<DOCNO> 101127 </DOCNO>
Symplectic and orthogonal Lie algebra technology for bosonic and


  To provide tools, especially L-operators, for use in studies of rational
Yang-Baxter algebras and quantum integrable models when the Lie algebras so(N)
(b_n, d_n) or sp(2n) (c_n) are the invariance algebras of their R matrices,
this paper develops a presentation of these Lie algebras convenient for the
context, and derives many properties of the matrices of their defining
representations and of the ad-invariant tensors that enter their multiplication
laws. Metaplectic-type representations of sp(2n) and so(N) on bosonic and on
fermionic Fock spaces respectively are constructed. Concise general expressions
(see (5.2) and (5.5) below) for their L-operators are obtained, and used to
derive simple formulas for the T operators of the rational RTT algebra of the
associated integral systems, thereby enabling their efficient treatment by
means of the algebraic Bethe ansatz.

</DOC>
<DOC>
<DOCNO> 68850 </DOCNO>
The electric dipole moment of the neutron in chiral perturbation theory


  We calculate the electric dipole moments of the neutron and the Lambda within
the framework of heavy baryon chiral perturbation theory. They are induced by
strong CP-violating terms of the effective Lagrangian in the presence of the
vacuum angle theta_0. The construction of such a Lagrangian is outlined and we
are able to give an estimate for theta_0.

</DOC>
<DOC>
<DOCNO> 152249 </DOCNO>
Descent Relation of Tachyon Condensation from Boundary String Field


  We analyze how lower-dimensional bosonic D-branes further decay, using the
boundary string field theory. Especially we find that the effective tachyon
potential of the lower-dimensional D-brane has the same profile as that of
D25-brane.

</DOC>
<DOC>
<DOCNO> 118966 </DOCNO>
Collapse of Low Mass Clouds in the Presence of UV Radiation Field


  The collapse of marginally Jeans unstable primordial gas clouds in the
presence of UV radiation field is discussed. Assuming that the dynamical
collapse proceeds approximately in an isothermal self-similar fashion, we
investigate the thermal evolution of collapsing central core until H$_2$
cooling dominates photoheating and the temperature drops to below $10^4$K.
Consequently, the mass of the cooled core is evaluated as $M_{cool}=3.6\times
10^6 M_\odot(I_{21}/1)^{-0.32}$. This scale depends only on the incident UV
intensity, and provides a lower limit to the mass of collapsed objects in the
UV radiation field.

</DOC>
<DOC>
<DOCNO> 85537 </DOCNO>
Initial data for two Kerr-like black holes


  We prove the existence of a family of initial data for the Einstein vacuum
equation which can be interpreted as the data for two Kerr-like black holes in
arbitrary location and with spin in arbitrary direction. When the mass
parameter of one of them is zero, this family reduces exactly to the Kerr
initial data. The existence proof is based on a general property of the Kerr
metric which can be used in other constructions as well. Further
generalizations are also discussed.

</DOC>
<DOC>
<DOCNO> 84762 </DOCNO>
Self-similar spherically symmetric wave maps coupled to gravity


  We investigate spherically symmetric continuously self-similar (CSS)
solutions in the SU(2) sigma model coupled to gravity. Using mixed numerical
and analytical methods, we provide evidence for the existence (for small
coupling) of a countable family of regular CSS solutions. This fact is argued
to have important implications for the ongoing studies of black hole formation
in the model.

</DOC>
<DOC>
<DOCNO> 8590 </DOCNO>
Raman Scattering cross section of Spin Ladders


  The Raman scattering spectra from magnetic excitations in an
antiferromagnetic spin-1/2 two leg ladder is investigated for weak and strong
interladder coupling. In the first case, a cusp in the Raman intensityis
obtained at a frequency twice the gap. In the second case, a peak at twice the
gap replaces the cusp. We discuss the relevance of our calculation to recent
experiments on CaV2O5 and Sr14Cu24O41.

</DOC>
<DOC>
<DOCNO> 170783 </DOCNO>
Entanglement Teleportation Through Cat-like States


  We first consider teleportation of entangled states shared between Claire and
Alice to Bob1 and Bob2 when Alice and the two Bobs share a single copy of a
GHZ-class state and where {\it all} the four parties are at distant locations.
We then generalize this situation to the case of teleportation of entangled
states shared between Claire1, Claire2, ....., Claire(N-1) and Alice to Bob1,
Bob2, ....., BobN when Alice and the N Bobs share a single copy of a Cat-like
state and where again {\it all} the 2N parties are at distant locations.

</DOC>
<DOC>
<DOCNO> 10867 </DOCNO>
Non-spiky density of states of an icosahedral quasicrystal


  The density of states of the ideal three-dimensional Penrose tiling, a
quasicrystalline model, is calculated with a resolution of 10 meV. It is not
spiky. This falsifies theoretical predictions so far, that spikes of width
10-20 meV are generic for the density of states of quasicrystals, and it
confirms recent experimental findings. The qualitative difference between our
results and previous calculations is partly explained by the small number of k
points that has usually been included in the evaluation of the density of
states of periodic approximants of quasicrystals. It is also shown that both
the density of states of a small approximant of the three-dimensional Penrose
tiling and the density of states of the ideal two-dimensional Penrose tiling do
have spiky features, which also partly explains earlier predictions.

</DOC>
<DOC>
<DOCNO> 150542 </DOCNO>
Supersymmetric Wilson Lines and Loops, and Super Non-Abelian Stokes


  We generalize the standard product integral formalism to incorporate
Grassmann valued matrices and show that the resulting supersymmetric product
integrals provide a natural framework for describing supersymmetric Wilson
Lines and Wilson Loops. We use this formalism to establish the supersymmetric
version of the non-Abelian Stokes theorem.

</DOC>
<DOC>
<DOCNO> 11680 </DOCNO>
Universal Amplitude Ratios of The Renormalization Group: Two-Dimensional


  The scaling form of the free-energy near a critical point allows for the
definition of various thermodynamical amplitudes and the determination of their
dependence on the microscopic non-universal scales. Universal quantities can be
obtained by considering special combinations of the amplitudes. Together with
the critical exponents they characterize the universality classes and may be
useful quantities for their experimental identification. We compute the
universal amplitude ratios for the Tricritical Ising Model in two dimensions by
using several theoretical methods from Perturbed Conformal Field Theory and
Scattering Integrable Quantum Field Theory. The theoretical approaches are
further supported and integrated by results coming from a numerical
determination of the energy eigenvalues and eigenvectors of the off-critical
systems in an infinite cylinder.

</DOC>
<DOC>
<DOCNO> 80967 </DOCNO>
Quasi-local Update Algorithms for Numerical Simulations of d=3 SU(2) LGT


  In the dual formulation of d=3 SU(2) LGT, the link variables are group
representations and valid configurations are those satisfying a number of
triangle inequalities. In \cite{lat99} algorithms for local updates that
automatically respect these constraints were described. It was also pointed out
there that these local updates were not ergodic. In this presentation, we
describe two different quasi-local updating algorithms which, in conjunction
with the local updates, appear to be ergodic.

</DOC>
<DOC>
<DOCNO> 10732 </DOCNO>
Charge-ordering phase transition and order-disorder effects in the Raman


  In the ac polarized Raman spectra of NaV2O5 we have found anomalous phonon
broadening, and an energy shift of the low-frequency mode as a function of the
temperature. These effects are related to the breaking of translational
symmetry, caused by electrical disorder that originates from the fluctuating
nature of the V {4.5+} valence state of vanadium. The structural correlation
length, obtained from comparisons between the measured and calculated Raman
scattering spectra, diverges at T< 5 K, indicating the existence of the
long-range charge order at very low temperatures, probably at T=0 K.

</DOC>
<DOC>
<DOCNO> 101311 </DOCNO>
Knots of Ten or Fewer Crossings of Algebraic Order Two


  The concordance orders of many algebraic order two knots of ten or fewer
crossings have been heretofore unknown. We use Casson-Gordon invariants and
twisted Alexander polynomials to find that, in all but one case, these knots do
not have concordance order two. We also find that a certain family of algebraic
order two twisted doubles of the unknot have infinite concordance order.

</DOC>
<DOC>
<DOCNO> 85087 </DOCNO>
String-Inspired Higher-Curvature Terms and the Randall-Sundrum Scenario


  We consider the O(a') string effective action, with Gauss-Bonnet
curvature-squared and fourth-order dilaton-derivative terms, which is derived
by a matching procedure with string amplitudes in five space-time dimensions.
We show that a non-factorizable metric of the Randall-Sundrum (RS) type, with
four-dimensional conformal factor Exp(-2 k|z|), can be a solution of the
pertinent equations of motion. The parameter k is found proportional to the
string coupling g_s and thus the solution appears to be non-perturbative. It is
crucial that the Gauss-Bonnet combination has the right (positive in our
conventions) sign, relative to the Einstein term, which is the case
necessitated by compatibility with string (tree) amplitude computations. We
study the general solution for the dilaton and metric functions, and thus
construct the appropriate phase-space diagram in the solution space. In the
case of an anti-de-Sitter bulk, we demonstrate that there exists a continuous
interpolation between (part of) the RS solution at z=infinity and an
(integrable) naked singularity at z=0. This implies the dynamical formation of
domain walls (separated by an infinite distance), thus restricting the physical
bulk space time to the positive z axis. Some brief comments on the possibility
of fine-tuning the four-dimensional cosmological constant to zero are also
presented.

</DOC>
<DOC>
<DOCNO> 67642 </DOCNO>
Probing Intermediate Mass Higgs Interactions at the CERN Large Hadron


  We analyze the potentiality of the CERN Large Hadron Collider to probe the
Higgs boson couplings to the electroweak gauge bosons. We parametrize the
possible deviations of these couplings due to new physics in a model
independent way, using the most general dimension--six effective lagrangian
where the SU(2)_L x U(1)_Y is realized linearly. For intermediate Higgs masses,
the decay channel into two photons is the most important one for Higgs searches
at the LHC. We study the effects of these new interactions on the Higgs
production mechanism and its subsequent decay into two photons. We show that
the LHC will be sensitive to new physics scales beyond the present limits
extracted from the LEP and Tevatron physics.

</DOC>
<DOC>
<DOCNO> 84998 </DOCNO>
Embedding variables in the canonical theory of gravitating shells


  A thin shell of light-like dust with its own gravitational field is studied
in the special case of spherical symmetry. The action functional for this
system due to Louko, Whiting, and Friedman is reduced to Kucha\v{r} form: the
new variables are embeddings, their conjugate momenta, and Dirac observables.
The concepts of background manifold and covariant gauge fixing, that underlie
these variables, are reformulated in a way that implies the uniqueness and
gauge invariance of the background manifold. The reduced dynamics describes
motion on this background manifold.

</DOC>
<DOC>
<DOCNO> 69441 </DOCNO>
A new approach to multi-jet calculations in hadron collisions


  The ALPHA algorithm to evaluate the exact, tree-level matrix elements is
reviewed in the context of multi-parton processes in QCD. The algorithm is
suited for the authomatic calculation of tree-level scattering amplitudes and
allows for straightforward inclusion of mass effects. It's CPU cost grows like
K^n (K constant, n number of external particles) as opposed to the factorial
growth of Feynman graphs. I also discuss the summation over colour
configurations which is designed to allow the construction of parton-level
event generators suitable to interfacing with a parton-shower evolution
including the effects of colour-coherence. Explicit results for the total rates
and differential distributions of processes with 8 final-state partons are
given.

</DOC>
<DOC>
<DOCNO> 120657 </DOCNO>
The Bright SHARC Survey: The Selection Function and its Impact on the


  We present the results of a set of simulations designed to quantify the
selection function of the Bright SHARC survey for distant clusters. The
statistical significance of the simulations relied on the creation of thousands
of artificial clusters with redshifts and luminosities in the range 0.25<z<0.95
and 0.5<L_X<10x10^44 erg/s (0.5-2.0 keV). We created 1 standard and 19 varied
distribution functions, each of which assumed a different set of cluster,
cosmological and operational parameters. The parameters we varied included the
values of Omega_0, Omega_Lambda, Beta, core radius and ellipticity. We also
investigated how non-standard surface brightness profiles; cooling flows; and
the ROSAT pointing target, influence the selection function in the Bright SHARC
survey. For our standard set we adopted the parameters used during the
derivation of the Bright SHARC Cluster X-ray Luminosity Function (CXLF), i.e.
Omega_0=1, Omega_Lambda=0 and an isothermal Beta model with beta=0.67, r_c=250
kpc and e=0.15. We found that certain parameters have a dramatic effect on our
ability to detect clusters, e.g. the presence of a NFW profile or a strong
cooling flow profile, or the value of r_c and beta. Other parameters had very
little effect, e.g. the type of ROSAT target and the cluster ellipticity. We
show also that all the tested parameters have only a small influence on the
computed luminosity of the clusters except the presence of a strong cooling
flow. We conclude that the CXLF presented in Nichol et al. (1999) is robust
(under the assumption of standard parameters), but stress the importance of
cluster follow-up in order to better constrain the morphology of the distant
clusters found in the Bright SHARC and other surveys.

</DOC>
<DOC>
<DOCNO> 39684 </DOCNO>
Signatures for a Cosmic Flux of Magnetic Monopoles


  Any early universe phase transition occurring after inflation has the
potential to populate the universe with a flux of magnetic monopoles.
Observations of galactic magnetic fields, as well as observations matched with
models for extragalactic magnetic fields, lead to the conclusion that monopoles
of mass $\lsim 10^{15}$ GeV are accelerated in these fields to relativistic
velocities. We explore the possible signatures of a cosmic flux of relativistic
monopoles impinging on the earth. The electromagnetically-induced signatures of
monopoles are reliable. The hadronically-induced signatures are highly
model-dependent. Among our findings are (i) the electromagnetic energy losses
of monopoles continuously initiate a protracted shower of small intensity; (ii)
monopoles may traverse the earth's diameter, making them a probe of the earth's
interior structure; (iii) in addition to the direct monopole Cherenkov signal
presently employed, a very attractive search strategy for monopoles is
detection of their radio-Cherenkov signal produced by the coherent
charge-excess in the $e^+-e^-$ shower - in fact, Cherenkov-detectors have the
potential to discover a monopole flux (or limit it) several orders of magnitude
below the theoretical Parker limit of $10^{-15}/\rm{cm}^2$/s/sr; (iv) it is
conceivable (but not compelling) that bound states of colored monopoles may be
the primary particles initiating the air showers observed above the GZK cutoff.

</DOC>
<DOC>
<DOCNO> 170554 </DOCNO>
Control of squeezed light pulse spectrum in the Kerr medium with an


  The consistent quantum theory of self-phase modulation (SPM) and cross-phase
modulation (XPM) for ultrashort light pulses (USP) in medium with electronic
Kerr-nonlinearity are developed. The approach makes use of momentum operator of
electrical field which takes account of the inertial behaviour of the
nonlinearity. The spectrum of quantum fluctuations of squeezed-quadrature
component as a function of response time of nonlinearity and values of
nonlinear phase shifts due to the SPM and XPM effects, is investigated.

</DOC>
<DOC>
<DOCNO> 117732 </DOCNO>
Gas Stripping of Dwarf Galaxies in Clusters of Galaxies


  Many clusters of galaxies contain an appreciable amount of hot gas, the
intracluster medium. As a consequence, gas will be stripped from galaxies that
move through the inter cluster medium, if the ram pressure exceeds the internal
gravitational force. We study the interaction between the intracluster medium
and an extended gas component of dwarf galaxies confined by a surrounding cold
dark matter halo analytically and numerically, using axisymmetric
two-dimensional hydrodynamical simulations at high resolution. The results show
that the gas within the dark matter halo is totally stripped in a typical
galactic cluster. The process of ram pressure stripping therefore must have
played an important role during the chemo-dynamical evolution of dwarf galaxies
in galactic clusters. Our results predict that most of the chemical evolution
of dwarf galaxies must have occurred at high redshift, before the virialized
cluster had formed.

</DOC>
<DOC>
<DOCNO> 118982 </DOCNO>
Looking for non-Gaussianity in the COBE-DMR data with spherical wavelets


  We present an analysis of the Gaussianity of the 4-year COBE-DMR data (in
HEALPix pixelisation) based on spherical wavelets. The skewness, kurtosis and
scale-scale correlation spectra are computed from the detail wavelet
coefficients at each scale. The sensitivity of the method to the orientation of
the data is also taken into account. We find a single detection of
non-Gaussianity at the $>99%$ confidence level in one of our statistics. We use
Monte-Carlo simulations to assess the statistical significance of this
detection and find that the probability of obtaining such a detection by chance
for an underlying Gaussian field is as high as 0.69. Therefore, our analysis
does not show evidence of non-Gaussianity in the COBE-DMR data.

</DOC>
<DOC>
<DOCNO> 70538 </DOCNO>
Economic Model for Neutrino Masses and Mixings


  Working in the framework of three chiral neutrinos with Majorana masses, we
investigate a scenario where the neutrino mass matrix is strictly off-diagonal
in the flavor basis, with all its diagonal entries precisely zero.

</DOC>
<DOC>
<DOCNO> 99813 </DOCNO>
On the Balazard-Saias criterion for the Riemann Hypothesis


  The authors modify the Balazard-Saias criterion for the Riemann hypothesis
by changing the cutoff of the Dirichlet series. They establish some asymptotic
results related to the modified criterion.

</DOC>
<DOC>
<DOCNO> 123101 </DOCNO>
Towards a model of Quintessential Inflation


  A model of quintessential inflation is presented, which manages to achieve
the requirements of both inflation and quintessence with natural values of the
mass-scales and parameters.

</DOC>
<DOC>
<DOCNO> 7955 </DOCNO>
Aging in a topological spin glass


  We have examined the nonconventional spin glass phase of the 2-dimensional
kagome antiferromagnet (H_3 O) Fe_3 (SO_4)_2 (OH)_6 by means of ac and dc
magnetic measurements. The frequency dependence of the ac susceptibility peak
is characteristic of a critical slowing down at Tg ~ 18K. At fixed temperature
below Tg, aging effects are found which obey the same scaling law as in spin
glasses or polymers. However, in clear contrast with conventional spin glasses,
aging is remarkably insensitive to temperature changes. This particular type of
dynamics is discussed in relation with theoretical predictions for highly
frustrated non-disordered systems.

</DOC>
<DOC>
<DOCNO> 179010 </DOCNO>
Point Form Electrodynamics and the Construction of Conserved Current


  A general procedure for constructing conserved electromagnetic current
operators, for both finite and infinite degree of freedom systems, is given. A
four-momentum operator consisting of matter, photon, and electromagnetic
interactions is assumed to be polynomial in photon creation and annihilation
operators. Commutators of the four-momentum operator with the four-vector
potential operator at the space-time point zero give the electromagnetic field
tensor and current operator at the space-time point zero. In this construction
there are no equations of motion to be satisfied and field operators at an
arbitrary space-time point-defined as the four-momentum translates of the
corresponding operators at the space-time point zero-are not local operators.
Several examples are given to show how the construction is carried out.

</DOC>
<DOC>
<DOCNO> 122480 </DOCNO>
Magnetocentrifugal acceleration of plasma in a nonaxisymmetric


  Violation of the axial synnetry of a magnetic field essentially modifies the
physics of the plasma outflow in the magnetosphere of rotating objects. In
comparison to the axisymmetric outflow, two new affects appear: more efficient
magnetocentrifugal acceleration of the plasma along particular field lines and
generation of MHD waves. Here, we use an ideal MHD approximation to study the
dynamics of a cold wind in the nonaxisymmetric magnetosphere. We obtain a
self-consistent analytical solution of the problem of cold plasma outflow from
a slowly rotating star with a slightly nonaxisymmetric magnetic field using
perturbation theory. In the axisymmetric (monopole-like) magnetic field, the
first term in the expansion of the terminating energy of the plasama in powers
of $\Omega$ is proportional to $\Omega^4$, where $\Omega$ is the angular
velocity of the central source. Violation of the axial symmetry of the magnetic
field crucially changes this dependence. The first correction to the energy of
the plasma becomes proportional to $\Omega$. Efficient magnetocentrifugal
acceleration occurs along the field lines curved initially in the direction of
the rotation. I argue that all necessary conditions for the efficient
magnetocentrifugal acceleration of the plasma exist in the radio pulsar
megnetosphere. We calculated the first correction of the rotational losses due
to the generation of the MHD waves and analysed the plasma acceleration by
these waves.

</DOC>
<DOC>
<DOCNO> 40546 </DOCNO>
Dalitz Analysis of the Decay $D^{0}\to K^{-}\pi^{+}\pi^{0}$


  We use data collected with the CLEO II detector to perform a high-statistics
measurement of the resonant substructure in $D^0 \to K^-\pi^+\pi^0$ decays. We
find the Dalitz Plot is well represented by a combination of seven
quasi-two-body decay channels ($\bar{K}^{*0} \pi^0$, $K^- \rho$, $K^{*-}
\pi^+$, $K^*_0(1430)^-\pi^+$, $\bar{K}^*_0(1430)^0 \pi^0$, $K^- \rho^+(1700)$,
and $K^*(1680)^- \pi^+$), plus a small non-resonant component. Using the
amplitudes and phases from this analysis, we calculate an integrated CP
asymmetry of $-0.031 \pm 0.086$.

</DOC>
<DOC>
<DOCNO> 123156 </DOCNO>
The Deep X-ray Radio Blazar Survey (DXRBS). II. New Identifications


  We have searched the archived, pointed ROSAT Position Sensitive Proportional
Counter data for blazars by correlating the WGACAT X-ray database with several
publicly available radio catalogs, restricting our candidate list to
serendipitous X-ray sources with a flat radio spectrum (alpha_r <= 0.70). This
makes up the Deep X-ray Radio Blazar Survey (DXRBS). Here we present new
identifications and spectra for 106 sources, including 86 radio-loud quasars,
11 BL Lacertae objects, and 9 narrow-line radio galaxies. Together with our
previously published objects and already known sources, our sample now contains
298 identified objects: 234 radio-loud quasars (181 flat-spectrum quasars: FSRQ
[alpha_r <= 0.50] and 53 steep-spectrum quasars: SSRQ), 36 BL Lacs, and 28
narrow-line radio galaxies. Redshift information is available for 96% of these.
Thus our selection technique is ~ 90% efficient at finding radio-loud quasars
and BL Lacs. Reaching 5 GHz radio fluxes ~ 50 mJy and 0.1-2.0 keV X-ray fluxes
a few x 10^-14 erg/cm^2/s, DXRBS is the faintest and largest flat-spectrum
radio sample with nearly complete (~ 85%) identification. We review the
properties of the DXRBS blazar sample, including redshift distribution and
coverage of the X-ray-radio power plane for quasars and BL Lacs. Additionally,
we touch upon the expanded multiwavelength view of blazars provided by DXRBS.
By sampling for the first time the faint end of the radio and X-ray luminosity
functions, this sample will allow us to investigate the blazar phenomenon and
the validity of unified schemes down to relatively low powers.

</DOC>
<DOC>
<DOCNO> 7951 </DOCNO>
Laser probing of atomic Cooper pairs


  We consider a gas of attractively interacting cold Fermionic atoms which are
manipulated by laser light. The laser induces a transition from an internal
state with large negative scattering length to one with almost no interactions.
The process can be viewed as a tunneling of atomic population between the
superconducting and the normal states of the gas. It can be used to detect the
BCS-ground state and to measure the superconducting order parameter.

</DOC>
<DOC>
<DOCNO> 122752 </DOCNO>
Upper limits to low energy antineutrino flux from GRB990705


  The detection of Gamma Ray Burst GRB990705 on 1999, July 5.66765 UT, pointing
to the Large Magellanic Clouds, suggested the search for a possible neutrino
counterpart, both in coincidence with and slightly before (or after) the photon
burst. We exploited such a possibility by means of the LVD neutrino telescope
(National Gran Sasso Laboratory, Italy), which has the capability to study
low-energy cosmic neutrinos. No evidence for any neutrino signal, over a wide
range of time durations, has been found, at the occurrence of GRB990705. Due to
the lack of information about both the source distance and its emission
spectrum, the results of the search are expressed in terms of upper limits, at
the Earth, to the antineutrino flux $\cdot$ cross-section, integrated over
different time durations. Moreover, assuming thermal antineutrino spectra at
the source, upper limits to the antineutrino flux, integrated over time
duration, for different spectral temperatures, are obtained. Based on these
limits and on the expectations for neutrino emission from collapsing
astrophysical objects, the occurrence of a gravitational stellar collapse can
be excluded up to a distance r approximately 50 kpc, in the case of time
coincidence with GRB990705, and r approximately 20 kpc, for the 24 hours
preceding it.

</DOC>
<DOC>
<DOCNO> 13228 </DOCNO>
The ferromagnetic q-state Potts model on three-dimensional lattices: a


  We study the phase diagram of the ferromagnetic $q$-state Potts model on the
various three-dimensional lattices for integer and non-integer values of $q>1$.
Our approach is based on a thermodynamically self-consistent Ornstein-Zernike
approximation for the two-point correlation functions. We calculate the
transition temperatures and, when the transition is first order, the jump
discontinuities in the magnetization and the internal energy, as well as the
coordinates of the critical endpoint in external field. Our predictions are in
very good agreement with best available estimates. From the numerical study of
the region of weak first-order transition, we estimate the critical value $q_c$
for which the transition changes from second to first-order. The $q->1$ limit
that describes the bond-percolation problem is also investigated.

</DOC>
<DOC>
<DOCNO> 118550 </DOCNO>
The Energy Spectrum of TeV Gamma-Rays from the Crab Nebula as measured


  The Crab Nebula has been observed by the HEGRA (High-Energy Gamma-Ray
Astronomy) stereoscopic system of imaging air Cherenkov telescopes (IACTs) for
a total of about 200 hrs during two observational campaigns: from September
1997 to March 1998 and from August 1998 to April 1999. The recent detailed
studies of system performance give an energy threshold and an energy resolution
for gamma-rays of 500 GeV and ~ 18%, respectively. The Crab energy spectrum was
measured with the HEGRA IACT system in a very broad energy range up to 20 TeV,
using observations at zenith angles up to 65 degrees. The Crab data can be
fitted in the energy range from 1 to 20 TeV by a simple power-law, which yields
dJg/dE = (2.79+/-0.02 +/- 0.5) 10^{-7} E^{-2.59 +/- 0.03 +/- 0.05}, ph m^{-2}
s^{-1} TeV^{-1} The Crab Nebula energy spectrum, as measured with the HEGRA
IACT system, agrees within 15% in the absolute scale and within 0.1 units in
the power law index with the latest measurements by the Whipple, CANGAROO and
CAT groups, consistent within the statistical and systematic errors quoted by
the experiments. The pure power-law spectrum of TeV gamma-rays from the Crab
Nebula constrains the physics parameters of the nebula environment as well as
the models of photon emission.

</DOC>
<DOC>
<DOCNO> 118179 </DOCNO>
Geodetic Precession and the Binary Pulsar B1913+16


  A change of the component separation in the profiles of the binary pulsar PSR
B1913+16 has been observed for the first time (Kramer 1998) as expected by
geodetic precession. In this work we extend the previous work by accounting for
recent data from the Effelsberg 100-m telescope and Arecibo Observatory and
testing model predictions. We demonstrate how the new information will provide
additional information on the solutions of the system geometry.

</DOC>
<DOC>
<DOCNO> 72058 </DOCNO>
Brane preheating


  We study brane-world preheating in massive chaotic inflationary scenario
where scalar fields are confined on the 3-brane. Assuming that quadratic
contribution in energy densities dominates the Hubble expansion rate during
preheating, the amplitude of inflaton decreases slowly relative to the standard
dust-dominated case. This leads to an efficient production of $\chi$ particles
via nonperturbative decay of inflaton even if its coupling is of order
$g=10^{-5}$. We also discuss massive particle creation heavier than inflaton,
which may play important roles for the baryo- and lepto-genesis scenarios.

</DOC>
<DOC>
<DOCNO> 122208 </DOCNO>
On ionization effects and abundance ratios in damped Lyman alpha systems


  The similarity between observed velocity structures of Al III and singly
ionized species in damped Lyman-alpha systems (DLAs) suggests the presence of
ionized gas in the regions where most metal absorption lines are formed. A
simplified model consisting of Region 1) a plane-parallel ionization bounded
region illuminated by an internal radiation field, and Region 2) a neutral
region with a negligible metal content is considered. We calculate
photoionization equilibrium models for region 1, and constrain the ionization
parameter by the observed N(Al III)/N(Si II) column density ratio. Under these
conditions we find that ionization effects are important. If these effects are
taken into account, the element abundance ratios in DLAs are quite consistent
with those observed in Milky Way stars and in H II regions of local
low-metallicity blue compact dwarf galaxies. In particular we cannot exclude
the same primary N origin in both DLAs and metal-poor galaxies. No depletion of
heavy elements on dust grains needs to be invoked, although our models do not
exclude the presence of little depletion. Although highly simplified and
relying on the strong assumption of a significantly lower metal content in
region 2, our model appears to be supported by recent data on a local DLA and
it is not in contradiction with the current knowledge on high redshift DLAs. If
correct, it offers a clear simplification in the understanding of heavy element
abundance ratios in DLAs and their comparison with the local Universe.

</DOC>
<DOC>
<DOCNO> 119835 </DOCNO>
On the redshift cut-off for flat-spectrum radio sources


  We use data from the Parkes Half-Jansky Flat-Spectrum (PHJFS) sample
(Drinkwater et al. 1997) to constrain the cosmic evolution in the co-moving
space density of radio sources in the top decade of the flat-spectrum radio
luminosity function (RLF). A consistent picture for the high-redshift evolution
is achieved using both simple parametric models, which are the first to allow
for distributions in both radio luminosity and spectral index, and variants of
the V / V_max test, some of which incorporate the effects of radio spectral
curvature. For the most luminous flat-spectrum objects, the PHJFS sample is
extremely similar to that used by Shaver et al. (1996, 1998) to argue for an
abrupt `redshift cut-off': a decrease by a factor ~30 in space density between
a peak redshift z~2.5 and z~5. Our analysis finds that the observable co-moving
volume is too small to make definitive statements about any redshift cut-off
for the most luminous flat-spectrum sources, although both constant-space
density (no cut-off) models and models with cut-offs as abrupt as those
envisaged by Shaver et al. are outside the 90% confidence region. The inference
that the decline in space density is most likely to be gradual, by a factor ~4
between z~2.5 and z~5, is in accordance with previous work on the RLF by Dunlop
& Peacock (1990), but different to the abrupt decline favoured by studies of
optically-selected quasars. Dust obscuration provides one explanation for this
difference. We show that a significant fraction of the most radio-luminous
flat-spectrum objects are Giga-Hertz Peaked Spectrum (GPS) rather than
Doppler-Boosted (DB) sources, complicating any interpretation of the redshift
cut-off.

</DOC>
<DOC>
<DOCNO> 11610 </DOCNO>
Effect of resonances on the transport properties of two-dimensional


  We study both analytically and numerically how the electronic structure and
the transport properties of a two-dimensional disordered system are modified in
the presence of resonances. The energy dependence of the density of states and
the localization length at different resonance energies and strengths of
coupling between resonances and random states are determined. The results show,
that at energy equals to the resonance energy there is an enhancement in the
density of states. In contrast, the localization length remains unaffected from
the presence of the resonances and is similar to the one of the standard
Anderson model. Finally, we calculate the diffusion constant as a function of
energy and we reveal interesting analogies with experimental results on light
scattering in the presence of Mie resonances.

</DOC>
<DOC>
<DOCNO> 117337 </DOCNO>
The Heats of Reactions. Calorimetry and Van't-Hoff. 2


  Earlier, the author found that for the biggest part of chemical reactions the
law of conservation of energy must have the following form: dU=dQ+PdV+SUM In
the present paper this result is confirmed by other experiments.

</DOC>
<DOC>
<DOCNO> 67817 </DOCNO>
The Nucleon Sigma Term from Threshold Parameters


  A new sum rule determines the nucleon sigma term by the \pi N elastic
scattering threshold parameters alone. This "threshold" value of \sigma(2\mu^2)
provides an independent check of existing values obtained from global
dispersive analyses, and also provides a realistic error assignment. Employing
a recent analysis of low energy (T_\pi < 100 MeV) \pi N data our sum rule
implies \sigma(2\mu^2) = 71\pm 9 MeV.

</DOC>
<DOC>
<DOCNO> 11938 </DOCNO>
Selective quantum evolution of a qubit state due to continuous


  We consider a two-level quantum system (qubit) which is continuously measured
by a detector. The information provided by the detector is taken into account
to describe the evolution during a particular realization of measurement
process. We discuss the Bayesian formalism for such ``selective'' evolution of
an individual qubit and apply it to several solid-state setups. In particular,
we show how to suppress the qubit decoherence using continuous measurement and
the feedback loop.

</DOC>
<DOC>
<DOCNO> 117265 </DOCNO>
Generalized Heitler-London Theory for H_3: A Comparison of the Surface


  The generalized Heitler-London (GHL) theory provides a straightforward way to
express the potential energy surface of H_3 in terms of Coulomb and exchange
energies which can be calculated either by perturbation theory or using the
surface integral method (SIM). By applying the Rayleigh-Schroedinger
perturbation theory, GHL theory for the quartet spin state of H_3 is shown to
yield results equivalent to the symmetrized Rayleigh-Schroedinger version of
symmetry adapted perturbation theory (SAPT). This equivalence allows a
comparison with the corresponding results obtained by the surface integral
method. The surface integral result calculated with a product of atomic wave
functions is found to have certain advantages over the perturbation approach.

</DOC>
<DOC>
<DOCNO> 150422 </DOCNO>
Brane Descent Relations in M-theory


  We discuss how the BPS branes of M-theory could be described as bound states
of non-BPS M10-branes. This conjectured M10-brane is constructed as an unstable
spacetime-filling brane in the massive eleven dimensional supergravity defined
with a Killing direction, such that 1) the BPS M9-brane is obtained after the
tachyonic mode of an M2-brane ending on it condenses, and 2) it gives the
non-BPS D9-brane of the type IIA theory upon reduction. The existence of other
non-BPS M-branes is also discussed, together with their possible stabilisation
within the Horava-Witten construction.

</DOC>
<DOC>
<DOCNO> 11032 </DOCNO>
Single-hole dynamics in dimerized and frustrated spin-chains


  We present a unified account for the coupled single-hole- and spin-dynamics
in the spin-gap phase of dimerized and frustrated spin-chains and two-leg spin
ladders. Based on the strong dimer-limit of a one-dimensional
$t_123$-$J_123$-model a diagrammatic approach is presented which employs a
mapping of the spin-Hamiltonian onto a pseudo-fermion bond-boson model. Results
for the single-hole spectrum are detailed. A finite quasi-particle weight is
observed and studied for a variety of system parameters. A comparison with
existing exact diagonalization data is performed and good agreement is found.

</DOC>
<DOC>
<DOCNO> 170648 </DOCNO>
The Bargmann representation for the quantum mechanics on a sphere


  The Bargmann representation is constructed corresponding to the coherent
states for a particle on a sphere introduced in: K. Kowalski and J.
Rembielinski, J. Phys. A: Math. Gen. 33, 6035 (2000). The connection is
discussed between the introduced formalism and the standard approach based on
the Hilbert space of square integrable functions on a sphere S^2.

</DOC>
<DOC>
<DOCNO> 170244 </DOCNO>
Entangling Atoms and Ions in Dissipative Environments


  Quantum information processing rests on our ability to manipulate quantum
superpositions through coherent unitary transformations, and to establish
entanglement between constituent quantum components of the processor. The
quantum information processor (a linear ion trap, or a cavity confining the
radiation field for example) exists in a dissipative environment. We discuss
ways in which entanglement can be established within such dissipative
environments. We can even make use of a strong interaction of the system with
its environment to produce entanglement in a controlled way.

</DOC>
<DOC>
<DOCNO> 100431 </DOCNO>
Witten solution of the Gelfand-Dikii hierarchy


  Among solutions of n-Gelfand-Dikii's hierarchy there exists a remarkable
solution W, which satisfies the string equation. We call it Witten's solution
because according to the Witten conjecture the function F(x_1, x_2, x_3,...) =
W(x_1,(x_2)/2, (x_3)/3,...) is the generating function for intersection nambers
of Mumford-Morita-Muller cohomological classes of the moduli space of n-spin
Riemann surfaces. This conjecture was proved by Kontsevich for n=2 and by
Witten himself for surfaces of genus 0.
    In this paper we find recurrence relations between coefficients of Taylor
series of W. This reduces the Witten's conjecture to conjecture that the
Mamford-Morita-Muller numbers satisfy to the same relations. These relations
give also an algorithm for calculation of $n$-spin Mamford-Morita-Muller
numbers in assuming that the Witten conjecture is true. Moreover we prove that
F(x_1,x_2,...,x_{n-1},0,0,...)= W(x_1, (x_2)/2,...,(x_{n-1})/(n-1),0,0,...).

</DOC>
<DOC>
<DOCNO> 116458 </DOCNO>
Noise-based switches and amplifiers for gene expression


  The regulation of cellular function is often controlled at the level of gene
transcription. Such genetic regulation usually consists of interacting
networks, whereby gene products from a single network can act to control their
own expression or the production of protein in another network. Engineered
control of cellular function through the design and manipulation of such
networks lies within the constraints of current technology. Here we develop a
model describing the regulation of gene expression, and elucidate the effects
of noise on the formulation. We consider a single network derived from
bacteriophage $\lambda$, and construct a two-parameter deterministic model
describing the temporal evolution of the concentration of $\lambda$ repressor
protein. Bistability in the steady-state protein concentration arises
naturally, and we show how the bistable regime is enhanced with the addition of
the first operator site in the promotor region. We then show how additive and
multiplicative external noise can be used to regulate expression. In the
additive case, we demonstrate the utility of such control through the
construction of a protein switch, whereby protein production is turned ``on''
and ``off'' using short noise pulses. In the multiplicative case, we show that
small deviations in the transcription rate can lead to large fluctuations in
the production of protein, and describe how these fluctuations can be used to
amplify protein production significantly. These novel results suggest that an
external noise source could be used as a switch and/or amplifier for gene
expression. Such a development could have important implications for gene
therapy.

</DOC>
<DOC>
<DOCNO> 7628 </DOCNO>
Distribution of the magnetic field and current density in


  A one-dimensional equation describing the distribution of the effective
vector potential $\bar A(y)$ across a film width, which holds for thin
($d<\lambda$) and thick ($d>\lambda$) films alike, is derived based on the
analysis of a 2D Maxwell-Londons equation for superconducting films in a
perpendicular magnetic field. The validity of this equation for a
finite-thickness film is verified by a numerical analysis. An approximation
dependence $\bar A(y)$, finite (with all of its derivatives) across the entire
film width, is found for films, being in the Meissner state. The flux-entry
field is evaluated for a film of arbitrary thickness. An approximation
expression is obtained for the distribution of the sheet current density in the
mixed state of a pin-free superconducting film with an edge barrier. The latter
approximation allows to estimate magnetic field concentration factor at the
film edge as a function of external magnetic field and geometrical parameters
of the sample.

</DOC>
<DOC>
<DOCNO> 117509 </DOCNO>
N-body simulations of interactions and mergings in small galaxy groups


  In this paper I focus on three topics related to the dynamical evolution of
small galaxy groups, for which the input of N-body simulations has been
decisive. These are the merging rates in compact groups, the properties of
remnants of multiple mergers, and the evolution of disc galaxies surrounded by
one or more satellites. The short dynamical times of compact groups make it
difficult to understand why such groups are observed at all. N-body simulations
have pointed out two possible classes of solutions to this problem. The first
one proposes that there is on-going formation of compact groups, or that the
longevity of the group is due to secondary infall. For the second class of
solutions the longevity of compact groups is due either to their specific
initial conditions, or to a massive common halo, encompassing the whole group.
I discuss here these alternatives, together with their respective advantages
and disadvantages. I then turn to the structure of remnants of multiple mergers
and compare the results of N-body simulations with the properties of observed
elliptical galaxies. Finally I discuss the dynamical evolution of a disc galaxy
surrounded by one or more spherical satellites.

</DOC>
<DOC>
<DOCNO> 13277 </DOCNO>
On the Number of Metastable States in a Stripe Glass


  We estimate the number of metastable states of a self generated stripe glass,
relevant for the formation of glassy doped Mott insulators. Using replica bound
states, we demonstrate that the configurational entropy is the difference
between the entropy of the stripe liquid and of an amorphous stripe solid with
phonon-type excitations. Using simple scaling laws we then determine the
relationship between the modulation length and the configurational entropy.

</DOC>
<DOC>
<DOCNO> 11947 </DOCNO>
Detecting self-similarity in surface microstructures


  The relative configurational entropy per cell as a function of length scale
is a sensitive detector of spatial self-similarity. For Sierpinski carpets the
equally separated peaks of the above function appear at the length scales that
depend on the kind of the carpet. These peaks point to the presence of
self-similarity even for randomly perturbed initial fractal sets. This is also
demonstrated for the model population of particles diffusing over the surface
considered by Van Siclen, Phys. Rev. E 56 (1997) 5211. These results allow the
subtle self-similarity traces to be explored.

</DOC>
<DOC>
<DOCNO> 122551 </DOCNO>
The Edge of the Solar System


  The population of the Kuiper Belt within 50 AU of the Sun has likely been
severely depleted by gravitational perturbations from the giant planets,
particularly Neptune. The density of Kuiper Belt objects is expected to be two
orders of magnitude higher just beyond 50 AU, where planetary perturbations are
insignificant. In 1998 and 1999, we surveyed for Kuiper Belt Objects (KBOs) in
6 fields of the ecliptic (total sky area 1.5 deg^2) to limiting magnitudes
between R=24.9 and R=25.9. This is deep enough to detect KBOs of diameter >~
160 km at a distance of 65 AU. We detected 24 objects. None of these objects,
however, is beyond 53 AU. Our survey places a 95% CL upper limit of Sigma<5
deg^-2 on the surface density of KBOs larger than ~160 km beyond 55 AU. This
can be compared to the surface density of ~6 deg^-2 of 160 km KBOs at distances
30--50 AU determined from this survey and previous shallower surveys. The mean
volume density of D>160 km KBOs in the 55--65 AU region is, at >95% confidence,
less than the mean density in the 30--50 AU region, and at most twothirds of
the mean density from 40--50 AU. Thus, a substantial density increase beyond 50
AU is excluded in this model-independent estimate, implying that some process
or event in the history of the Solar System has truncated the distribution of
160-km planetesimals at ~50 AU. A dense primordial disk could be present beyond
50 AU if it contains only smaller objects, or is sufficiently thin and inclined
to have escaped detection in our 6 survey fields.

</DOC>
<DOC>
<DOCNO> 178882 </DOCNO>
Shift of the 2$^+_1$ state of $^{10}$Be in the ternary cold fission of


  Recent experimental data indicate that in the ternary cold fission of
$^{252}$Cf the energy of the first excited state of the accompanying light
cluster $^{10}$Be is decreased by an amount ranging between $\approx$ 6 and 26
keV. A model is proposed to calculate the shift of the vibrational 2$^+_1$
state in $^{10}$Be when its heavy companions are the even-even nuclei
$^{146}$Ba and $^{96}$Sr. The stiffness parameters of the $\beta$-vibrations
are calculated within the self-consistent Hartree-Fock method with BCS pairing
correlations taken into account, and its change is determined by the
interaction of the light cluster with the heavy fragments. The results are
pointing to a dependence of the shift magnitude and signature on the relative
distance between the three clusters and their mutual orientation. Eventually it
is the anharmonic perturbation of the spherical vibrator which is responsible
for obtaining a negative energy shift of the 2$^+_1$ state.

</DOC>
<DOC>
<DOCNO> 116249 </DOCNO>
Sun Microsystem's AutoClient and management of computer farms at BaBar


  Modern HEP experiments require immense amounts of computing power. In the
BaBar experiment at SLAC, most of it is provided by Solaris SPARC systems.
AutoClient, a product of Sun Microsystems, was designed to make setting up and
managing large numbers of Solaris systems more straightforward. AutoClient
machines keep all filesystems, except swap, on a server and employ CacheFS to
cache them onto a local disk, which makes them Field Replaceable Units with
performance of stand-alone systems. We began exploring the technology in Summer
1998, and currently operate online, reconstruction, analysis and console
AutoClient farms with the total number of nodes exceeding 400. Although the
technology has been available since 1995, it has not been widely used, and the
available documentation does not adequately cover many important details of
AutoClient installation and management. This paper discusses various aspects of
our experience with AutoClient, including tips and tricks, performance and
maintainability, scalability and server requirements, existing problems and
possible future enhancements.

</DOC>
<DOC>
<DOCNO> 13538 </DOCNO>
The order-disorder transition of the (3x3)Sn/Ge(111) phase


  Growing attention has been drawn in the past years to the \alpha-phase (1/3
monolayer) of Sn on Ge(111), which undergoes a transition from the low
temperature (3x3) phase to the room temperature (\sqrt3 x \sqrt3)R30 one. On
the basis of scanning tunnelling microscopy experiments, this transition was
claimed to be the manifestation of a surface charge density wave (SCDW), i.e. a
periodic redistribution of charge, possibly accompanied by a periodic lattice
distortion, which determines a change of the surface symmetry. As further
experiments with different techniques were being performed, increasing doubts
were cast about the SCDW model. We have measured by He scattering the long
range order of the 1/3 monolayer phase of Sn on the Ge(111) surface throughout
the phase transition. The transition has been found of the order-disorder type
with a critical temperature Tc=220 K. The expected 3-State Potts critical
exponents are shown to be consistent with the observed power law dependence of
the (3x3) order parameter and its correlation length close to Tc, thus
excluding a charge density wave driven phase transition.

</DOC>
<DOC>
<DOCNO> 120742 </DOCNO>
Galaxy Collisions and Star Formation


  We present a brief overview of some recent observations of colliding galaxies
and relevant numerical simulations. These are compared, and details of the
locations and history of collision induced star formation are explored, with
possible application to star formation at earlier epochs.

</DOC>
<DOC>
<DOCNO> 101898 </DOCNO>
The role of connectedness in the structure and the action of group of


  By proving that, if the quotient space S(X) of the connected components of
the locally compact metric space (X,d) is compact, then the full group I(X,d)
of isometries of X is closed in C(X,X) with respect to the pointwise topology,
i.e., that I(X,d) coincides in this case with its Ellis' semigroup, we complete
the proof of the following:
  Theorem
  (a) If S(X) is not compact, I(X,d) need not be locally compact, nor act
  properly on X.
  (b) If S(X) is compact, I(X,d) is locally compact but need not act properly
  on X.
  (c) If, especially, X is connected, the action (I(X,d),X) is proper.

</DOC>
<DOC>
<DOCNO> 152306 </DOCNO>
Type IIA and Heterotic String Vacua in D=2


  We study type IIA string theory compactified on Calabi-Yau fourfolds and
heterotic string theory compactified on Calabi-Yau threefolds times a
two-torus. We derive the resulting effective theories which have two space-time
dimensions and preserve four supercharges. The duality between such vacua is
established at the level of the effective theory. For type IIA vacua with
non-trivial Ramond-Ramond background fluxes a superpotential is generated. We
show that for a specific choice of background fluxes and a fourfold which has
the structure of a threefold fibred over a sphere the superpotential coincides
with the superpotential recently proposed by Taylor and Vafa in
compactifications of type IIB string theory on a threefold.

</DOC>
<DOC>
<DOCNO> 71117 </DOCNO>
At the edge of nuclear stability: nonlinear quantum amplifiers


  We show that nuclei lying at the edge of stability can behave as nonlinear
quantum amplifiers. A tiny change in the nucleon-nucleon interaction can
trigger a much bigger change in the binding energy of these systems, relative
to the few-cluster breakup threshold.

</DOC>
<DOC>
<DOCNO> 13565 </DOCNO>
Multi Parametric Deformed Heisenberg Algebras: A Route to Complexity


  We introduce a generalization of the Heisenberg algebra which is written in
terms of a functional of one generator of the algebra, $f(J_0)$, that can be
any analytical function. When $f$ is linear with slope $\theta$, we show that
the algebra in this case corresponds to $q$-oscillators for $q^2 = \tan
\theta$. The case where $f$ is a polynomial of order $n$ in $J_0$ corresponds
to a $n$-parameter deformed Heisenberg algebra. The representations of the
algebra, when $f$ is any analytical function, are shown to be obtained through
the study of the stability of the fixed points of $f$ and their composed
functions. The case when $f$ is a quadratic polynomial in $J_0$, the simplest
non-linear scheme which is able to create chaotic behavior, is analyzed in
detail and special regions in the parameter space give representations that
cannot be continuously deformed to representations of Heisenberg algebra.

</DOC>
<DOC>
<DOCNO> 11576 </DOCNO>
Evidence for the droplet picture in the 3D $\pm J$ spin glass


  A bivariate version of the multicanonical Monte Carlo method and its
application to the simulation of the three-dimensional $\pm J$ Ising spin glass
are described. We found the autocorrelation time associated with this
particular multicanonical method was approximately proportional to the system
volume, which is a great improvement over previous methods applied to
spin-glass simulations. The principal advantage of this version of the
multicanonical method however was its ability to access information predictive
of low-temperature behavior. At low temperatures we found results on the
three-dimensional $\pm J$ Ising spin glass consistent with the droplet picture:
the order-parameter distribution function $P(q)$ converged to two
delta-function peaks, and the Binder parameter approached unity as the system
size was increased. We also discuss the structure of the ground-state
degeneracy, introducing the concept of zero-energy droplets. The size
distribution of the zero-energy droplets was found to produce the two
delta-function peaks of $P(q)$.

</DOC>
<DOC>
<DOCNO> 151433 </DOCNO>
Leaving the BPS bound: Tunneling of classically saturated solitons


  We discuss quantum tunneling between classically BPS saturated solitons in
two-dimensional theories with N=2 supersymmetry and a compact space dimension.
Genuine BPS states form shortened multiplets of dimension two. In the models we
consider there are two degenerate shortened multiplets at the classical level,
but there is no obstruction to pairing up through quantum tunneling. The
tunneling amplitude in the imaginary time is described by instantons. We find
that the instanton is nothing but the 1/4 BPS saturated ``wall junction,''
considered previously in the literature in other contexts. Two central charges
of the superalgebra allow us to calculate the instanton action without finding
the explicit solution (it is checked, though, numerically, that the saturated
solution does exist). We present a quantum-mechanical interpretation of the
soliton tunneling.

</DOC>
<DOC>
<DOCNO> 99967 </DOCNO>
The polynomial property (V)


  Given Banach spaces E and F, we denote by ${\mathcal P}(^k!E,F)$ the space of
all k-homogeneous (continuous) polynomials from E into F, and by ${\mathcal
P}_{wb}(^k!E,F)$ the subspace of polynomials which are weak-to-norm continuous
on bounded sets. It is shown that if E has an unconditional finite dimensional
expansion of the identity, the following assertions are equivalent: (a)
${\mathcal P}(^k!E,F)={\mathcal P}_{wb}(^k!E,F)$; (b) ${\mathcal
P}_{wb}(^k!E,F)$ contains no copy of $c_0$; (c) ${\mathcal P}(^k!E,F)$ contains
no copy of $\ell_\infty$; (d) ${\mathcal P}_{wb}(^k!E,F)$ is complemented in
${\mathcal P}(^k!E,F)$. This result was obtained by Kalton for linear
operators. As an application, we show that if E has Pe\l czy\'nski's property
(V) and satisfies ${\mathcal P}(^k!E) ={\mathcal P}_{wb}(^k!E)$ then, for all
F, every unconditionally converging $P\in{\mathcal P}(^k!E,F)$ is weakly
compact. If E has an unconditional finite dimensional expansion of the
identity, then the converse is also true.

</DOC>
<DOC>
<DOCNO> 101798 </DOCNO>
Exponents of an irreducible plane curve singularity


  We give an explicit formula for the exponents (i.e. the spectra up to the
shift by one) of an irreducible plane curve singularity in terms of Puiseux
pairs. As an application we prove in this case Hertling's conjecture that the
variance (i.e. the square of the standard deviation) of the exponents is
bounded by the difference between the maximal and minimal exponents divided by
12.

</DOC>
<DOC>
<DOCNO> 12438 </DOCNO>
Pseudo-Casimir force in confined nematic polymers


  We investigate the pseudo-Casimir force in a slab of material composed of
nematically ordered long polymers. We write the total mesoscopic energy
together with the constraint connecting the local density and director
fluctuations and evaluate the corresponding fluctuation free energy by standard
methods. It leads to a pseudo-Casimir force of a different type than in the
case of standard, short molecule nematic. We investigate its separation
dependence and its magnitude and explicitly derive the relevant limiting cases.

</DOC>
<DOC>
<DOCNO> 101476 </DOCNO>
De Rham Cohomology and Hodge decomposition for Quantum Groups


  Let G=G(t,z) be one of the N^2-dimensional bicovariant first order
differential calculi for the quantum groups GL_q(N), SL_q(N), O_q(N), or
Sp_q(N), where q is a transcendental complex number and z is a regular
parameter. It is shown that the de Rham cohomology of Woronowicz' external
algebra G^ coincides with the de Rham cohomologies of its left-coinvariant, its
right-coinvariant and its (twosided) coinvariant subcomplexes. In the cases
GL_q(N) and SL_q(N) the cohomology ring is isomorphic to the coinvariant
external algebra G^_{inv} and to the vector space of harmonic forms. We prove a
Hodge decomposition theorem in these cases. The main technical tool is the
spectral decomposition of the quantum Laplace-Beltrami operator.
 Keywords: quantum groups, bicovariant differential calculi, de Rham
cohomology, Laplace-Beltrami operator, Hodge theory

</DOC>
<DOC>
<DOCNO> 99792 </DOCNO>
On the Extension of B. Sz.-Nagy's Dilation Theorem to Linear Pencils of


  The explicit constructions of minimal isometric, and minimal unitary
dilations of an arbitrary linear pencil of operators $T(\lambda)=T_0+\lambda
T_1$ consisting of contractions on a separable Hilbert space for $|\lambda
|=1$, which generalize the classical constructions (the case $T_1=0$), are
presented. In contrast to the classical case these dilations are essentially
non-unique.

</DOC>
<DOC>
<DOCNO> 122715 </DOCNO>
The Discovery of a Giant H-alpha Filament in NGC 7213


  The nearby Seyfert galaxy NGC 7213 has been imaged in H-alpha and HI with the
CTIO 1.5 m telescope and with the Australia Telescope Compact Array (ATCA),
respectively. Optically NGC 7213 looks undisturbed and relatively featureless
but the continuum-subtracted H-alpha image shows a 19 kpc long filament located
approximately 18.6 kpc from the nucleus. The H-alpha filament could be neutral
gas photo-ionized by the active nucleus, as has been suggested for the Seyfert
galaxy NGC 5252, or shock-ionized by a jet interacting with the surrounding HI,
as has been suggested for the radio galaxy PKS 2240-41. The HI map reveals NGC
7213 to be a highly disturbed system suggesting a past merging event.

</DOC>
<DOC>
<DOCNO> 120738 </DOCNO>
Bayesian joint estimation of non-Gaussianity and the power spectrum


  We propose a rigorous, non-perturbative, Bayesian framework which enables one
jointly to test Gaussianity and estimate the power spectrum of CMB
anisotropies. It makes use of the Hilbert space of an harmonic oscillator to
set up an exact likelihood function, dependent on the power spectrum and on a
set of parameters $\alpha_i$, which are zero for Gaussian processes. The latter
can be expressed as series of cumulants; indeed they perturbatively reduce to
cumulants. However they have the advantage that their variation is essentially
unconstrained. Any truncation(i.e.: finite set of $\alpha_i$) therefore still
produces a proper distribution - something which cannot be said of the only
other such tool on offer, the Edgeworth expansion. We apply our method to Very
Small Array (VSA) simulations based on signal Gaussianity, showing that our
algorithm is indeed not biased.

</DOC>
<DOC>
<DOCNO> 11418 </DOCNO>
Angle resolved photoemission spectroscopy of Sr_2CuO_2Cl_2 - a revisit


  We have investigated the lowest binding-energy electronic structure of the
model cuprate Sr_2CuO_2Cl_2 using angle resolved photoemission spectroscopy
(ARPES). Our data from about 80 cleavages of Sr_2CuO_2Cl_2 single crystals give
a comprehensive, self-consistent picture of the nature of the first
electron-removal state in this model undoped CuO_2-plane cuprate. Firstly, we
show a strong dependence on the polarization of the excitation light which is
understandable in the context of the matrix element governing the photoemission
process, which gives a state with the symmetry of a Zhang-Rice singlet.
Secondly, the strong, oscillatory dependence of the intensity of the Zhang-Rice
singlet on the exciting photon-energy is shown to be consistent with
interference effects connected with the periodicity of the crystal structure in
the crystallographic c-direction. Thirdly, we measured the dispersion of the
first electron-removal states along G->(pi,pi) and G->(pi,0), the latter being
controversial in the literature, and have shown that the data are best fitted
using an extended t-J-model, and extract the relevant model parameters. An
analysis of the spectral weight of the first ionization states for different
excitation energies within the approach used by Leung et al. (Phys. Rev. B56,
6320 (1997)) results in a strongly photon-energy dependent ratio between the
coherent and incoherent spectral weight. The possible reasons for this
observation and its physical implications are discussed.

</DOC>
<DOC>
<DOCNO> 102783 </DOCNO>
Invitation to higher local fields, Part I, section 18: On ramification


  Ramification theory of monogenic extensions of complete discrete valuation
fields is presented. Relations to Kato's conductor are discussed.

</DOC>
<DOC>
<DOCNO> 70207 </DOCNO>
Uncertainty of Predicted High Q2 Structure Functions due to


  The HERA luminosity upgrade is expected to provide statistically significant
measurements of the proton structure functions at 0.5<x<0.7 and very high Q2
(Q2>>M_{Z}^2). The behaviour of the parton densities (PDFs) in this high x, Q2
regime is predicted from DGLAP evolution of PDF parametrizations from lower Q2
fits of the data. Uncertainties in the PDFs at high x may propagate to lower x
through DGLAP evolution at very high Q2. In this presentation the behaviour of
the PDFs at high x is reexamined with different parametrizations that have been
tried earlier, and with somewhat different constraints, set primarily by
existing fixed target data. We present and discuss the effects at Q2=40000GeV^2
and compare our results with uncertainties obtained from propagation of
experimental errors at high x, high Q2 DIS data.

</DOC>
<DOC>
<DOCNO> 11597 </DOCNO>
Stability of the Period-Doubled Core of the 90-degree Partial in Silicon


  In a recent Letter [N. Lehto and S. Oberg, Phys. Rev. Lett. 80, 5568 (1998)],
Lehto and Oberg investigated the effects of strain fields on the core structure
of the 90-degree partial dislocation in silicon, especially the influence of
the choice of supercell periodic boundary conditions in theoretical
simulations. We show that their results for the relative stability between the
two structures are in disagreement with cell-size converged tight-binding total
energy (TBTE) calculations, which suggest the DP core to be more stable,
regardless of the choice of boundary condition. Moreover, we argue that this
disagreement is due to their use of a Keating potential.

</DOC>
<DOC>
<DOCNO> 68048 </DOCNO>
The proton and the photon, who is probing whom in electroproduction?


  The latest results on the structure of the proton and the photon as seen at
HERA are reviewed while discussing the question posed in the title of the talk.

</DOC>
<DOC>
<DOCNO> 85107 </DOCNO>
Domain walls without cosmological constant in higher order gravity


  We consider a class of higher order corrections with arbitrary power $n$ of
the curvature tensor to the standard gravity action in arbitrary space-time
dimension $D$. The corrections are in the form of Euler densities and are
unique at each $n$ and $D$. We present a generating functional and an explicit
form of the corresponding conserved energy-momentum tensors. The case of
conformally flat metrics is discussed in detail. We show that this class of
corrections allows for domain wall solutions since, despite the presence of
higher powers of the curvature tensor, the singularity structure at the wall is
of the same type as in the standard gravity. However, models with higher order
corrections have larger set of domain wall solutions and the existence of these
solutions no longer depends on the presence of cosmological constants. We find
for example that the Randall-Sundrum scenario can be realized without any need
for bulk and/or brane cosmological constant.

</DOC>
<DOC>
<DOCNO> 13828 </DOCNO>
Realization of an ultra-high magnetic field on a nano-scale


  In tunnel junctions of which at least one side is a ferromagnet, very large
magnetic polarization change ($\approx 0.1 \mu_B$) and splitting of the spin up
and spin down Fermi energy ($\approx 0.1 eV$) can be created under steady state
finite current conditions (bias voltage $\approx$ 1 volt). This is {\bf much
higher} than can be created by the highest magnetic field on earth. We
illustrate this with a specific calculation of a recently observed very large
Hall effect in the Al side of a Co-I-Al tunnel junction. Other recent
experiments that support this idea are discussed.

</DOC>
<DOC>
<DOCNO> 68317 </DOCNO>
Effects of flavor conserving CP violating phases in SUSY models


  I summarize our recent works on the effects of flavor conserving CP violating
phases in SUSY models on $B$ and $K$ phenomenology.

</DOC>
<DOC>
<DOCNO> 170109 </DOCNO>
Entropy decrease in Quantum Zeno Effect


  If a measurement process is regarded as an irreversible process, then by
Second law of thermodynamics the entropy should increase after any measurement
process. By the same spirit a quantum system undergoing repeated measurement
should show strong irreversibility leading to entropy production. On the
contrary we show that in quantum Zeno effect setting the entropy of a quantum
system decreases and goes to zero after a large number of measurements. We
discuss the entropy change under continuous measurement model and show that
entropy can decrease if we use a more accurate measuring apparatus.

</DOC>
<DOC>
<DOCNO> 120269 </DOCNO>
Public Release of N-body simulation and related data by the Virgo


  We are making available on the WWW a selection of the archived data from
N-body simulations carried out by the Virgo consortium and related groups. This
currently includes: (i) time-slice, lightcone and cluster data from the two
$10^9$-particle Hubble volume simulations described by Evrard 1998; (ii)
time-slice data from simulations of 4 different cold dark matter cosmological
models with $256^3$ particles analysed by Jenkins et al 1998; (iii) Dark halo
catalogs, merger trees and galaxy catalogs from the GIF project described by
Kauffmann et al 1999. Basic software is supplied to read the data. The data can
be accessed from: http://www.mpa-garching.mpg.de/Virgo/data_download.html

</DOC>
<DOC>
<DOCNO> 100638 </DOCNO>
Lectures on differentials, generalized differentials and on some


  These notes contain a survey of some aspects of the theory of differential
modules and complexes as well as of their generalization, that is, the theory
of $N$-differential modules and $N$-complexes. Several applications and
examples coming from physics are discussed. The commun feature of these
physical applications is that they deal with the theory of constrained or gauge
systems. In particular different aspects of the BRS methods are explained and a
detailed account of the $N$-complexes arising in the theory of higher spin
gauge fields is given.

</DOC>
<DOC>
<DOCNO> 169879 </DOCNO>
Multipartite pure-state entanglement and the generalized GHZ states


  We show that not all 4-party pure states are GHZ reducible (i.e., can be
generated reversibly from a combination of 2-, 3- and 4-party maximally
entangled states by local quantum operations and classical communication
asymptotically) through an example, we also present some properties of the
relative entropy of entanglement for those 3-party pure states that are GHZ
reducible, and then we relate these properties to the additivity of the
relative entropy of entanglement.

</DOC>
<DOC>
<DOCNO> 69035 </DOCNO>
Comment on "On the Origin of the OZI Rule in QCD", by N. Isgur and H. B.


  We comment on the recent paper (hep-lat/0005006) by Isgur and Thacker on the
origin of the OZI rule in QCD. We show that instantons explain the sign and
magnitude of the observed OZI-violating amplitude in all mesonic channels, not
just in the $\eta'$ channel. We comment on the role of instantons in hadronic
spectroscopy and the relation between instantons and the large $N_c$ limit of
QCD.

</DOC>
<DOC>
<DOCNO> 169656 </DOCNO>
Structure behind Mechanics II: Deduction


  This paper proves that protomechanics, previously introduced in
quant-ph/9909025, deduces both quantum mechanics and classical mechanics. It
does not only solve the problem of the arbitrariness on the operator ordering
for the quantization procedure, but also that of the analyticity at the exact
classical-limit of $\hbar =0 $. In addition, proto-mechanics proves valid also
for the description of a half-spin.

</DOC>
<DOC>
<DOCNO> 40113 </DOCNO>
Measurement of the W Boson Mass with the Collider Detector at Fermilab


  We present a measurement of the W boson mass using data collected with the
CDF detector during the 1994-95 collider run at the Fermilab Tevatron. A fit to
the transverse mass spectrum of a sample of 30,115 W -> enu events recorded in
an integrated luminosity of 84 pb^(-1) gives a mass Mw = 80.473 +- 0.065(stat.)
+- 0.092(syst.) GeV/c^2. A fit to the transverse mass spectrum of a sample of
14,740 W -> munu events from 80 pb^(-1) gives a mass Mw = 80.465 +-
0.100(stat.) +- 0.103(syst.) GeV/c^2. The dominant contributions to the
systematic uncertainties are the uncertainties in the electron energy scale and
the muon momentum scale, 0.075 GeV/c^2 and 0.085 GeV/c^2, respectively. The
combined value for the electron and muon channel is Mw = 80.470 +- 0.089
GeV/c^2. When combined with previously published CDF measurements, we obtain Mw
= 80.433 +- 0.079 GeV/c^2.

</DOC>
<DOC>
<DOCNO> 120658 </DOCNO>
Precursors of gamma-ray bursts: a clue to the burster's nature


  In relativistic strongly magnetized winds outflowing from the fast-rotating
compact progenitors of gamma-ray bursts (GRBs) there are three regions where
powerful high-frequency emission may be generated: (i) the thermal photosphere,
(ii) the region of the internal wind instability and (iii) the region of the
wind interaction with an ambient gas. This results in a multicomponent
structure of GRBs. The emission from the thermal photosphere may be observed as
a weak precursor to the main burst. The precursor should have a blackbody-like
spectrum with the mean energy of photons of $\sim 1$ MeV, and its intensity
should be tens to hundreds of times smaller than that of the main GRB emission.
Observations of such precursors with future $\gamma$-ray missions like GLAST
can clarify the nature of bursters.

</DOC>
<DOC>
<DOCNO> 99584 </DOCNO>
Finite Dimensional Representations of Quadratic Algebras with Three


  The finite dimensional representations of associative quadratic algebras with
three generators are investigated by using a technique based on the deformed
parafermionic oscillator algebra. One application on the calculation of the
eigenvalues of the two-dimensional superintegrable systems is discussed.

</DOC>
<DOC>
<DOCNO> 85461 </DOCNO>
Scaling solutions from interacting fluids


  We examine the dynamical implications of an interaction between some of the
fluid components of the universe. We consider the combination of three matter
components, one of which is a perfect fluid and the other two are interacting.
The interaction term generalizes the cases found in scalar field cosmologies
with an exponential potential. We find that attracting scaling solutions are
obtained in several regions of parameter space, that oscillating behaviour is
possible, and that new curvature scaling solutions exist. We also discuss the
inflationary behaviour of the solutions and present some of the constraints on
the strength of the coupling, namely those arising from nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 170282 </DOCNO>
Reply to `No Contradictions between Bohmian and quantum mechanics'


  Marchildon's claim (quant-ph/0007068) regarding Ghose's papers
(quant-ph/0001024 and 0003037) is shown to be erroneous.

</DOC>
<DOC>
<DOCNO> 7782 </DOCNO>
Ab-initio Theoretical Description of the Interrelation between


  The cubic lattice symmetry of ferromagnetic homogeneously disordered alloys
is when a compositional modulation is imposed. This can have a profound
influence on the magnetocrystalline anisotropy energy (MAE). We describe our
ab-initio theory of this effect and use the framework of concentration waves
with the electronic structure described within the spin-polarised relativistic
Korringa-Kohn-Rostoker coherent-potential approximation. We find that ordering
produces a 2 order of magnitude increase in the MAE as well as altering the
equilibrium direction of magnetisation. Using the same theoretical framework we
also examine directional compositional order produced by magnetic annealing
with an explicit study of permalloy.

</DOC>
<DOC>
<DOCNO> 85143 </DOCNO>
Cylindrically symmetric perfect-fluid universes


  The aim of this paper is to examine some obtained exact solutions of the
Einstein-Maxwell equations, especially their properties from a chronological
point of view. Each our spacetime is stationary cylindrically symmetric and it
is filled up with an perfect fluid that is electrically charged. There are two
classes of solutions and examples of each of them are investigated. We give
examples of the first class both for the vanishing as well as for the
non-vanishing Lorentz force.

</DOC>
<DOC>
<DOCNO> 100334 </DOCNO>
Mirror symmetry for concavex vector bundles on projective spaces


  Let V be a vector bundle in $\PP^m$ and X the zero locus of a generic section
of V. Assume that X is contained in Y with normal bundle the pullback of the
negative part of V. Relations between the Gromov-Witten theories of Y and X are
described by means of a suitably constructed Gromov-Witten theory in $\PP^m$.
We apply mirror symmetry to the latter to evaluate the gravitational
descendants of Y supported in X.

</DOC>
<DOC>
<DOCNO> 99373 </DOCNO>
Dual Baxter equations and quantization of Affine Jacobian


  A quantum integrable model is considered which describes a quantization of
affine hyper-elliptic Jacobian. This model is shown to possess the property of
duality: a dual model with inverse Planck constant exists such that the
eigen-functions of its Hamiltonians coincide with the eigen-functions of
Hamiltonians of the original model. We explain that this duality can be
considered as duality between homologies and cohomologies of quantized affine
hyper-elliptic Jacobian.

</DOC>
<DOC>
<DOCNO> 120359 </DOCNO>
Magnification cross-sections of gravitational lensing by galaxies in


  For a wide variety of cosmological models characterized by the cosmic mass
density $\Omega_M$ and the normalized cosmological constant $\Omega_{\Lambda}$,
we derive an analytic expression for the estimate of magnification
cross-sections by an ensemble of isothermal spheres as models of galactic mass
distributions. This provides a simple approach to demonstrate how the lensing
probability by galaxies depends on the cosmological parameters. An immediate
consequence is that, while a non-zero cosmological constant indeed leads to a
significant increase of the lensing probability as it has been shown in the
literature, only a small fraction of sky to $z\sim 3$ can be moderately ($\mu
\sim 1.3$) lensed by galaxies even in a $\Lambda$-dominated flat universe.
Therefore, whether or not there is a nonzero cosmological constant, it is
unlikely that the overall quasar counts have been seriously contaminated by the
presence of galactic lenses.

</DOC>
<DOC>
<DOCNO> 12224 </DOCNO>
Dislocation nucleation and vacancy formation during high-speed


  Recently, a dislocation free deformation mechanism was proposed by Kiritani
et al., based on a series of experiments where thin foils of fcc metals were
deformed at very high strain rates. In the experimental study, they observed a
large density of stacking fault tetrahedra, but very low dislocation densities
in the foils after deformation. This was interpreted as evidence for a new
dislocation-free deformation mechanism, resulting in a very high vacancy
production rate.
  In this paper we investigate this proposition using large-scale computer
simulations of bulk and thin films of copper. To favour such a dislocation-free
deformation mechanism, we have made dislocation nucleation very difficult by
not introducing any potential dislocation sources in the initial configuration.
Nevertheless, we observe the nucleation of dislocation loops, and the
deformation is carried by dislocations. The dislocations are nucleated as
single Shockley partials.
  The large stresses required before dislocations are nucleated result in a
very high dislocation density, and therefore in many inelastic interactions
between the dislocations. These interactions create vacancies, and a very large
vacancy concentration is quickly reached.

</DOC>
<DOC>
<DOCNO> 178977 </DOCNO>
Light Front Nuclear Theory and the HERMES Effect


  I discuss the use of light cone variables to compute the nucleonic and
mesonic components of nuclear wave functions. A Lagrangian and its
energy-momentum tensor $T^{^+\mu}$ is used to define the total momentum
operators $P^\mu$. The aim is to use wave functions, expressed in terms of
plus-momentum variables, which are used to analyze high energy experiments such
as deep inelastic scattering, Drell-Yan production, (e,e') and (p,p')
reactions. We discuss infinite nuclear matter within the mean field
approximation; finite nuclei using the mean field approximation;
nucleon-nucleon scattering, within the one boson exchange approximation; and,
infinite nuclear matter including the effects of two-nucleon correlations.
Standard good results for nuclear saturation properties are obtained, with a
possible improvement in the lowered value, 180 MeV, of the computed nuclear
compressibility. In our approach, manifest rotational invariance emerges at the
end of the calculation. Thus nuclear physics can be done in a manner in which
modern nuclear dynamics can be implemented and symmetries are respected. A
salient feature is that $\omega,\sigma$ and $\pi$ mesons are obtained as
important constituents. These can contribute coherently to enhance nuclear
electroproduction cross sections for longitudinal virtual photons at low $Q^2$,
while depleting the cross section for transverse photons. Thus the recent
HERMES inelastic lepton-nucleus scattering data at low $Q^2$ and small $x$ can
be described using photon-meson and meson-nucleus couplings which are
consistent with constraints obtained from meson decay widths, nuclear
structure, deep inelastic scattering, and lepton pair production data. Our
model makes a variety of testable predictions.

</DOC>
<DOC>
<DOCNO> 102742 </DOCNO>
Representations of the Exceptional Lie superalgebra E(3,6): I.


  Recently one of the authors obtained a classification of simple
infinite-dimensional Lie superalgebras of vector fields which extends the
well-known classification of E. Cartan in the Lie algebra case. The list
consists of many series defined by simple equations, and of several exceptional
superalgebras, among them E(3,6).
  In the article we study irreducible representations of the exceptional Lie
superalgebra E(3,6). This superalgebra has s\ell(3)\times s\ell(2)\times
g\ell(1) as the zero degree component of its consistent \ZZ-grading which leads
us to believe that its representation theory has potential for physical
applications.

</DOC>
<DOC>
<DOCNO> 68743 </DOCNO>
Matter effects for `just so' oscillations


  We study the effect of the matter term on the evolution of the solar
neutrinos when the neutrino parameters are those of the `just-so' case. The
extreme non-adiabatic effects at the edge of the sun reduce the expression for
the survival probability in the just-so case to that of the vacuum case. This
conclusion is independent of the width of the extreme non-adiabatic region,
which is a function of the density profile of the sun beyond $r > 0.9 R_s$.
However, in its propagation, neutrino encounters regions of moderate
(non-extreme) non-adiabticity. Neutrino traversal through these regions give
corrections to the survival probability which are profile dependent.

</DOC>
<DOC>
<DOCNO> 151717 </DOCNO>
On supermembrane actions on Calabi-Yau 3-folds


  In this note we examine the supermembrane action on Calabi-Yau 3-folds. We
write down the Dirac-Born-Infeld part of the action, and show that it is
invariant under the rigid spacetime supersymmetry.

</DOC>
<DOC>
<DOCNO> 101593 </DOCNO>
An Introduction To Small Divisors


  This is an introduction to small divisors problems. The material treated in
this book was brought together for a PhD course I tought at the University of
Pisa in the spring of 1999. Here is a Table of Contents: Part I One Dimensional
Small Divisors. Yoccoz's Theorems 1. Germs of Analytic Diffeomorphisms.
Linearization 2. Topological Stability vs. Analytic Linearizability 3. The
Quadratic Polynomial: Yoccoz's Proof of the Siegel Theorem 4. Douady-Ghys'
Theorem. Continued Fractions and the Brjuno Function 5. Siegel-Brjuno Theorem,
Yoccoz's Theorem. Some Open Problems 6. Small Divisors and Loss of
Differentiability Part II Implicit Function Theorems and KAM Theory 7.
Hamiltonian Systems and Integrable Systems 8. Quasi-Integrable Hamiltonian
Systems 9. Nash-Moser's Implicit Function Theorem 10. From Nash-Moser's Theorem
to KAM: Normal Form of Vector Fields on the Torus Appendices A1.
Uniformization, Distorsion and Quasi-conformal maps A2. Continued Fractions A3.
Distributions, Hyperfunctions. Hypoellipticity and Diophantine Conditions

</DOC>
<DOC>
<DOCNO> 71485 </DOCNO>
Solving the Solar and Atmospheric Neutrino Problems with Supersymmetry


  The simplest unified extension of the Minimal Supersymmetric Standard Model
with bi-linear R--Parity violation provides a predictive scheme for neutrino
masses which can account for the observed atmospheric and solar neutrino
anomalies. Despite the smallness of neutrino masses R-parity violation is
observable at present and future high-energy colliders, providing an
unambiguous cross-check of the model.

</DOC>
<DOC>
<DOCNO> 122229 </DOCNO>
Period changes in omega Centauri RR Lyrae stars


  A century of observations of omega Centauri allows us to accurately follow
the period changes of a large sample of variable stars. Although the period
changes are composed of monotone and irregular changes, period increases
dominate in most of the RRab stars. The typical period increase rates are of
the same order of magnitude as model calculations predict for the evolved,
redward phase of horizontal branch evolution. For the 44 well observed RRab
stars which show monotonic period changes, a mean rate of 0.15 d/Myr has been
found. The period changes of the first overtone RRc type stars show a much more
complex, irregular behavior.

</DOC>
<DOC>
<DOCNO> 178990 </DOCNO>
Elastic Form Factors in Point-form Approach


  Using the point-form approach to relativistic quantum mechanics, a covariant
framework is presented for the calculation of proton and neutron
electromagnetic form factors. Results for charge radii, magnetic moments, and
electric as well as magnetic form factors are produced using the wave functions
obtained in the so-called Goldstone-boson-exchange constituent quark model. All
the predictions are found in remarkable agreement with existing experimental
data.

</DOC>
<DOC>
<DOCNO> 121035 </DOCNO>
Evidences for two Gamma-Ray Burst afterglow emission regimes


  We applied cosmological and absorption corrections to the X-ray and optical
afterglow fluxes of a sample of Gamma-Ray Burst sources of known distance. We
find a good correlation in X-rays and that the GRBs in our sample form two well
defined classes. We tentatively interpret them as radiative and adiabatic
afterglow behaviours in the framework of the fireball model for GRBs. We do not
observe this correlation at optical wavelengths. This discrepancy with the
model may be due to the absorption in the source vicinity.

</DOC>
<DOC>
<DOCNO> 13658 </DOCNO>
The Strength of First and Second Order Phase Transitions from Partition


  We present a numerical technique employing the density of partition function
zeroes (i) to distinguish between phase transitions of first and higher order,
(ii) to examine the crossover between such phase transitions and (iii) to
measure the strength of first and second order phase transitions in the form of
latent heat and critical exponents. These techniques are demonstrated in
applications to a number of models for which zeroes are available.

</DOC>
<DOC>
<DOCNO> 85367 </DOCNO>
Sectors of spherical homothetic collapse


  A study is undertaken of the gravitational collapse of spherically symmetric
thick shells admitting a homothetic Killing vector field under the assumption
that the energy momentum tensor corresponds to the absence of a pure outgoing
component of field. The energy-momentum tensor is not specified beyond this,
but is assumed to satisfy the strong and dominant energy conditions. The metric
tensor depends on only one function of the similarity variable and the energy
conditions identify a class of functions ${\cal F}$ to which the metric
function may belong. The possible global structure of such space-times is
determined, with particular attention being paid to singularities and their
temporal nature (naked or censored). It is shown that there are open subsets of
${\cal F}$ which correspond to naked singularities; in this sense, such
singularities are stable. Furthermore, it is shown that these singularities can
arise from regular (continuous), asymptotically flat initial data which deviate
from the trivial data by an arbitrarily small amount.

</DOC>
<DOC>
<DOCNO> 69089 </DOCNO>
Peripheral Production of Sigmas in Proton Proton Collisions


  The Pomeron, which dominates high energy elastic and diffractive hadronic
processes, must be largely gluonic in nature. We use a recent picture of a
scalar glueball/sigma system with coupling of the sigma to glue determined from
experiment to predict strong peripheral sigma production seen in the p p
$\pi^o\pi^o$ final state.

</DOC>
<DOC>
<DOCNO> 122916 </DOCNO>
Proper motion of very low mass stars and brown dwarfs in the Pleiades


  We report proper motion measurements for 25 very-low mass (VLM) star and
brown dwarf (BD) candidates of the Pleiades cluster previously identified by
Bouvier et al. (1998). Proper motions are measured with an accuracy of 9
mas/yr, compared to an expected tangential motion of about 50 mas/yr for
Pleiades members. Of the 25 candidates, 15 have a membership probability of 95%
or more and 7 are rejected as being field dwarfs. The 3 remaining candidates
exhibit independent evidence for membership (lithium absorption or long-term
proper motion). From the firm identification of Pleiades VLM and BD members,
the cluster's substellar mass function is revised to dN/dM \propto M^{-0.5} in
the mass range from 0.04 to 0.3 M_solar.

</DOC>
<DOC>
<DOCNO> 170273 </DOCNO>
Quantum no-deleting principle and some of its implications


  Unmeasureability of a quantum state has important consequences in practical
implementation of quantum computers. Like copying, deleting of an unknown state
from among several copies is prohibited. This is called no-deletion prinicple.
Here, we present a no deleting principle for qudits. We obtain a bound on
$N$-to-$M$ deleting and show that the quality of deletion drops exponentially
with the number of copies to be deleted. In addition, we investigate
conditional, state-dependent and approximate quantum deleting of unknown
states. We prove that unitarity does not allow us to delete copies from an
alphabet of two non-orthogonal states exactly. Further, we show that
no-deleting principle is consistent with no-signalling.

</DOC>
<DOC>
<DOCNO> 71703 </DOCNO>
Properties of the scalar mesons $f_0(1370)$, $f_0(1500)$ and $f_0(1710)$


  In the three-state mixing framework, considering the possible glueball
components of $\eta$ and $\eta^\prime$, we investigate the hadronic decays of
$f_0(1370)$, $f_0(1500)$ and $f_0(1710)$ into two pseudoscalar mesons. The
quarkonia-glueball content of the three states is determined from the fit to
the new data presented by the WA102 Collaboration. We find that these data are
insensitive to the possible glueball components of $\eta$ and $\eta^\prime$.
Furthermore, we discuss some properties of the mass matrix describing the
mixing of the isoscalar scalar mesons.

</DOC>
<DOC>
<DOCNO> 85512 </DOCNO>
Homotopic Classification of Yang-Mills Vacua Taking into Account


  In this letter we study the existence of theta-vacuum states in Yang-Mills
theories defined over asymptotically flat, stationary space-times taking into
account not only the topology but the complicated causal structure of these
space-times, too. By a result of Chrusciel and Wald, apparently causality makes
all vacuum states, seen by a distant observer, homotopically equivalent making
the introduction of theta-terms unnecessary in (causally) effective
Lagrangians.
  But a more careful study shows that certain twisted classical vacuum states
survive even in this case eventually leading to the conclusion that the concept
of ``theta-vacua'' is meaningful in the case of general Yang-Mills theories. We
give a classification of these vacuum states based on Isham's results showing
that the Yang-Mills vacuum has the same complexity as in the flat Minkowskian
case hence the general CP-problem is not more complicated than the well-known
flat one.

</DOC>
<DOC>
<DOCNO> 119534 </DOCNO>
The enigmatic soft X-ray NLS1 RX J0134.2-4258


  We report the discovery and analysis of the follow-up ROSAT pointed
observation, an ASCA observation and optical and radio observations of the
enigmatic Narrow-Line Seyfert 1 galaxy RX J0134.2-4258. While its spectrum was
one of the softest observed from an AGN during the ROSAT All-Sky Survey, its
spectrum was found to be dramatically harder during a pointed observation
although the count rate remained constant. In the pointed observation we found
that the spectrum is softer when it is fainter, and spectral fitting
demonstrates that it is the hard component that is variable. The ASCA
observation confirms the presence of a hard X-ray power law, the slope of which
is rather flat compared with other NLS1s. Survey and follow-up radio
observations reveal that RX J0134.2-4258 is also unusual in that it is a member
of the rare class of radio-loud NLS1s, and, with R=71, it holds the current
record for the largest radio-to-optical ratio in NLS1s. We discuss possible
scenarios to explain its strange behaviour.

</DOC>
<DOC>
<DOCNO> 9843 </DOCNO>
Axioms and uniqueness theorem for Tsallis entropy


  The Shannon-Khinchin axioms for the ordinary information entropy are
generalized in a natural way to the nonextensive systems based on the concept
of nonextensive conditional entropy, and a complete proof of the uniqueness
theorem for the Tsallis entropy is presented.

</DOC>
<DOC>
<DOCNO> 10811 </DOCNO>
Quantum Coherence of the Ground State of a Mesoscopic Ring


  We discuss the phase coherence properties of a mesoscopic normal ring coupled
to an electric environment via Coulomb interactions. This system can be mapped
onto the Caldeira-Leggett model with a flux dependent tunneling amplitude. We
show that depending on the strength of the coupling between the ring and the
environment the free energy can be obtained either by a Bethe ansatz approch
(for weak coupling) or by using a perturbative expression which we derive here
(in the case of strong coupling). We demonstrate that the zero-point
fluctuations of the environment can strongly suppress the persistent current of
the ring below its value in the absence of the environment. This is an
indication that the equilibrium fluctuations in the environment disturb the
coherence of the wave functions in the ring. Moreover the influence of quantum
fluctuations can induce symmetry breaking seen in the polarization of the ring
and in the flux induced capacitance.

</DOC>
<DOC>
<DOCNO> 121817 </DOCNO>
Origin and Destiny of Dark Matter Halos: Cosmological Matter Exchange


  [Abridged] We analyze the exchange of dark matter between halos, subhalos,
and their environments in a high-resolution cosmological N-body simulation of a
Lambda CDM cosmology. At each analyzed redshift z we divide the dark matter
particles into 4 components: (i) isolated galactic halos, (ii) subhalos, (iii)
the diffuse medium of group and cluster halos, and (iv) the background outside
of virialized halos. We follow the time evolution of the mass distribution and
flows between these components and provide fitting functions for the exchange
rates. We use our derived exchange rates to gauge the importance of metal
redistribution in the universe due solely to gravity-induced interactions. The
diffuse metallicity in clusters is predicted to be ~40% that in isolated
galaxies (~55% of groups) at z=0, and should be lower only slightly by z=1,
consistent with observations. The metallicity of the diffuse media in poor
groups is expected to be lower by a factor of 5 by z~2, in agreement with the
observed metallicity of damped Ly$\alpha$ systems. The metallicity of the
background IGM is predicted to be (1-3)x10^{-4} that of z=0 clusters, also
consistent with observations. The agreement of predicted and observed trends
indicates that gravitational interaction alone may play an important role in
metal enrichment of the intra-cluster and intergalactic media.

</DOC>
<DOC>
<DOCNO> 118017 </DOCNO>
ISO-SWS Observations of OMC-1: H_2 and Fine Structure Lines


  Using the Short-Wavelength-Spectrometer on the Infrared Space Observatory
(ISO), we obtained near- and mid-infrared spectra toward the brightest H_2
emission peak of the Orion OMC-1 outflow. A wealth of emission and absorption
features were detected, dominated by 56 H_2 ro-vibrational and pure rotational
lines reaching from H_2 0-0 S(1) to 0-0 S(25). The spectra also show a number
of H I recombination lines, atomic and ionic fine structure lines, and
molecular lines of CO and H_2O. Between 6 and 12 mu the emission is dominated
by PAH features. The H_2 level column density distribution shows no signs of
fluorescent excitation or a deviation from an ortho-to-para ratio of three. It
shows an excitation temperature which increases from about 600 K for the lowest
rotational and vibrational levels to about 3200 K at level energies E(v,J)/k >
14 000 K. No single steady state shock model can reproduce the observed H_2
excitation. The higher energy H_2 levels may be excited either thermally in
non-dissociative J-shocks, through non-thermal collisions between fast ions and
molecules with H_2 in C-shocks, or they are pumped by newly formed H_2
molecules. The highest rotational levels may be populated by yet another
mechanism, such as the gas phase formation of H_2 through H^-.

</DOC>
<DOC>
<DOCNO> 83265 </DOCNO>
Bagging and Boosting a Treebank Parser


  Bagging and boosting, two effective machine learning techniques, are applied
to natural language parsing. Experiments using these techniques with a
trainable statistical parser are described. The best resulting system provides
roughly as large of a gain in F-measure as doubling the corpus size. Error
analysis of the result of the boosting technique reveals some inconsistent
annotations in the Penn Treebank, suggesting a semi-automatic method for
finding inconsistent treebank annotations.

</DOC>
<DOC>
<DOCNO> 150507 </DOCNO>
Quintessence in brane cosmology


  In order to reconcile the non conventional character of brane cosmology with
standard Friedmann cosmology, we introduce in this paper a slowly-varying
quintessence scalar field in the brane and analyse the cosmological solutions
corresponding to some equations of state for the scalar field. Different
compensation mechanisms between the cosmological constant in the bulk and the
constant tension resulting from the combined effect of ordinary matter and the
quintessence scalar field are derived or assumed. It has been checked that the
Randall-Sundrum approach is not necessarily the best procedure to reconcile
brane and standard cosmologies, and that there exists at least another
compensating mechanism that reproduces a rather conventional behaviour for an
accelerating universe.

</DOC>
<DOC>
<DOCNO> 12101 </DOCNO>
Fermion Damping Rate Effects in Cold Dense Matter


  We review the non-Fermi or marginal liquid behavior of a relativistic QED
plasma. In this medium a quasiparticle has a damping rate that depends linearly
on the distance between its energy and the Fermi surface. We stress that this
dependence is due to the long-range character of the magnetic interactions in
the medium. Finally, we study how the quark damping rate modifies the gap
equation of color superconductivity, reducing the value of the gap at the Fermi
surface.

</DOC>
<DOC>
<DOCNO> 122469 </DOCNO>
What is the Highest Plausible Redshift of Luminous Quasars?


  The recent discoveries of luminous quasars at high redshifts imply that black
holes more massive than a few billion solar masses have been assembled already
when the universe was less than a billion years old. We show that the existence
of these black holes is not surprising in popular hierarchical models of
structure formation. For example, the black hole needed to power the quasar
SDSS 1044-0125 at redshift z=5.8 can arise naturally from the growth of stellar
mass seeds forming at z>10, when typical values are assumed for the radiative
accretion efficiency and the bolometric accretion luminosity in Eddington
units. Nevertheless, SDSS 1044-0125 yields a non-trivial constraint on a
combination of these parameters. Extrapolating our model to future surveys, we
derive the highest plausible redshift for quasars which are not lensed or
beamed, as a function of their apparent magnitude. We find that at a limiting
magnitude of K(AB)=20, quasar surveys can yield strong constraints on the
growth of supermassive black holes out to z=10.

</DOC>
<DOC>
<DOCNO> 11917 </DOCNO>
Optimizing Schroedinger functionals using Sobolev gradients:


  In this paper we study the application of the Sobolev gradients technique to
the problem of minimizing several Schr\"odinger functionals related to timely
and difficult nonlinear problems in Quantum Mechanics and Nonlinear Optics. We
show that these gradients act as preconditioners over traditional choices of
descent directions in minimization methods and show a computationally
inexpensive way to obtain them using a discrete Fourier basis and a Fast
Fourier Transform. We show that the Sobolev preconditioning provides a great
convergence improvement over traditional techniques for finding solutions with
minimal energy as well as stationary states and suggest a generalization of the
method using arbitrary linear operators.

</DOC>
<DOC>
<DOCNO> 169850 </DOCNO>
Computing with highly mixed states


  We consider quantum computing in the k-qubit model where the starting state
of a quantum computer consists of k qubits in a pure state and n-k qubits in a
maximally mixed state. We ask the following question: is there a general method
for simulating an arbitrary m-qubit pure state quantum computation by a quantum
computation in the k-qubit model? We show that, under certain constraints, this
is impossible, unless m=O(k+ log n).

</DOC>
<DOC>
<DOCNO> 9064 </DOCNO>
Model of Hydrophobic Attraction in Two and Three Dimensions


  An earlier one-dimensional lattice model of hydrophobic attraction is
extended to two and three dimensions and studied by Monte Carlo simulation. The
solvent-mediated contribution to the potential of mean force between
hydrophobic solute molecules and the solubility of the solute are determined.
As in the earlier model, an inverse relation is observed between the strength
and range of the hydrophobic attraction. The mean force no longer varies
monotonically with distance, as it does in one dimension, but has some
oscillations, reflecting the greater geometrical complexity of the lattice in
the higher dimensions. In addition to the strong attraction at short distances,
there is now also a local minimum in the potential of depth about $kT$ at a
distance of three lattice spacings in two dimensions and one of depth about
$2kT$ at a distance of two lattice spacings in three dimensions. The solubility
of the solute is found to decrease with increasing temperature at low
temperatures, which is another signature of the hydrophobic effect and also
agrees with what had been found in the one-dimensional model.

</DOC>
<DOC>
<DOCNO> 40291 </DOCNO>
Measurement of triple gauge boson couplings from WW production at LEP


  A measurement of triple gauge boson couplings is presented, based on W-pair
data recorded by the OPAL detector at LEP during 1998 at a centre-of-mass
energy of 189 GeV with an integrated luminosity of 183 pb^-1. After combining
with our previous measurements at centre-of-mass energies of 161-183 GeV we
obtain k_g=0.97 +0.20 -0.16, g_1^z=0.991 +0.060 -0.057 and lambda_g=-0.110
+0.058 -0.055, where the errors include both statistical and systematic
uncertainties and each coupling is determined by setting the other two
couplings to their SM values. These results are consistent with the Standard
Model expectations.

</DOC>
<DOC>
<DOCNO> 119089 </DOCNO>
Abundance of Terrestrial Planets by Microlensing


  Terrestrial planets may be detected using the gravitational microlensing
technique. This was demonstrated in the high magnification event
MACHO-98-BLG-35. Observing strategies aimed at measuring the abundance of
terrestrial planets are discussed, using both existing telescopes and planned
telescopes.

</DOC>
<DOC>
<DOCNO> 11337 </DOCNO>
Switching of Geometric Phase in Degenerate Systems


  The geometric and open path phases of a four-state system subject to time
varying cyclic potentials are computed from the Schr\"{o}dinger equation. Fast
oscillations are found in the non-adiabatic case. For parameter values such
that the system possesses degenerate levels, the geometric phase becomes
anomalous, undergoing a sign switch. A physical system to which the results
apply is a molecular dimer with two interacting electrons. Additionally, the
sudden switching of the geometric phase promises to be an efficient control in
two-qubit quantum computing.

</DOC>
<DOC>
<DOCNO> 170542 </DOCNO>
Quantum-State Engineering of Multiple Trapped Ions for Center-of-Mass


  We propose a scheme to generate a superposition with arbitrary coefficients
on a line in phase space for the center-of-mass vibrational mode of N ions by
means of isolating all other spectator vibrational modes from the
center-of-mass mode. It can be viewed as the generation of previous methods for
preparing motional states of one ion. For large number of ions, we need only
one cyclic operatin to generate such a superposition of many coherent states.

</DOC>
<DOC>
<DOCNO> 67857 </DOCNO>
How Neutrinos Get Mass and What Other Things May Happen Besides


  In this talk I address the theoretical issue of what new physics is required
to make $m_\nu \neq 0$. I then discuss what other things may happen besides
neutrino oscillations. In particular I consider a possible new scenario of
leptogenesis in R parity nonconserving supersymmetry.

</DOC>
<DOC>
<DOCNO> 72246 </DOCNO>
On Radiative Weak Annihilation Decays


  We discuss a little-studied class of weak decay modes sensitive to only one
quark topology at leading order in G_F: M --> m gamma, where M,m are mesons
with completely distinct flavor quantum numbers. Specifically, they proceed via
the annihilation of the valence quarks through a W and the emission of a single
hard photon, and thus provide a clear separation between CKM and strong
interaction physics. We survey relevant calculations performed to date, discuss
experimental discovery potential, and indicate interesting future directions.

</DOC>
<DOC>
<DOCNO> 69651 </DOCNO>
Exchange-degenerate Regge trajectories: a fresh look from resonance and


  The exchange-degeneracy of the mesonic $f$, $\omega $, $\rho $ and $a_{2}$
Regge trajectories, dominant at moderate and high energies in hadron elastic
scattering, is analyzed from two viewpoints. The first one concerns the masses
of the resonances lying on these trajectories; the second one deals with the
total cross-sections and the ratios of the real to the imaginary parts of the
forward amplitudes of hadron and photon induced reactions. Neither set of data
supports exact exchange-degeneracy.

</DOC>
<DOC>
<DOCNO> 11838 </DOCNO>
Coupling of two superconductors through a ferromagnet : evidence for a


  We report measurements of the temperature dependence of the critical current
in Josephson junctions consisting of conventional superconducting banks of Nb
and a weakly ferromagnetic interlayer of a Cu$_x$Ni$_{1-x}$ alloy, with $x$
around 0.5. With decreasing temperature $I_c$ generally increases, but for
specific thicknesses of the ferromagnetic interlayer, a maximum is found
followed by a strong decrease down to zero, after which $I_c$ rises again. Such
a sharp cusp can only be explained by assuming that the junction changes from a
0-phase state at high temperatures to a $\pi$-phase state at low temperatures.

</DOC>
<DOC>
<DOCNO> 169676 </DOCNO>
On balance of information in bipartite quantum communication systems:


  We adopt the view according to which information is the primary physical
entity that posseses objective meaning. Basing on two postulates that (i)
entanglement is a form of quantum information corresponding to internal energy
(ii) sending qubits corresponds to work, we show that in the closed bipartite
quantum communication systems the information is conserved. We also discuss
entanglement-energy analogy in context of the Gibbs-Hemholtz-like equation
connecting the entanglement of formation, distillable entanglement and bound
entanglement. Then we show that in the deterministic protocols of distillation
the information is conserved. We also discuss the objectivity of quantum
information in context of information interpretation of quantum states and
alghoritmic complexity.

</DOC>
<DOC>
<DOCNO> 117975 </DOCNO>
Kinetic theory of cosmic ray and gamma-ray production in supernova


  Abbreviated Abstract: A kinetic model of particle acceleration in supernova
remnants (SNRs) is extended to study the cosmic ray (CR) and associated high
energy gamma-ray production during SN shock propagation through the
inhomogeneous circumstellar medium of a progenitor star that emits a strong
wind. The wind forms a low-density bubble surrounded by a swept-up shell of
interstellar matter. Gamma rays are produced as a result of decay of pions
which in turn are the result of collisions of CRs with nuclei of the thermal
plasma. The time evolution of the SNRs is followed numerically, taking into
account the nonlinear backreaction of the accelerated CRs. Examples typical for
SN type Ib and SN type II explosions are considered. Apart from the
confirmation of the known fact that acceleration is extremely rapid and that
the upper momentum cutoff is reached almost immediately after the explosion due
to the high wind magnetic field, it is also shown that the CRs are accelerated
with high efficiency. The CR energy spectrum, ultimately produced in the SNRs,
has a power law form with index = 2.0 to 2.1 in a wide energy range up to a
maximum energy which is about 10^14 eV if the CR diffusion coefficient is as
small as the Bohm limiting value. However, the expected pi^0-decay gamma-ray
flux is considerably lower than in the case of a uniform interstellar medium; a
relatively high gamma-ray luminosity in the TeV band, detectable at distances
of several kpc, is only expected in the case of a relatively dense ISM with a
number density above 10/cc.

</DOC>
<DOC>
<DOCNO> 70059 </DOCNO>
Global Features of Nucleus-Nucleus Collisions in the Ultrarelativistic


  HIJING generator simulation of nucleus-nucleus collisions at
ultrarelativistic energies are presented. Is shown, that the global
characteristics of nucleus-nucleus collisions, such as of distribution of a
charge multiplicity, total and electromagnetic transverse energy over
pseudorapidity are rather sensitive to some predictions of formation models of
high-exited nuclear medium, namely parton energy losses in dense nuclear
matter. This losses results to appearance of a broad maximum in global variable
distributions over pseudorapidity. The most profound of this effect occurs at
central heavy ion collisions at LHC energy.

</DOC>
<DOC>
<DOCNO> 14180 </DOCNO>
Modified critical correlations close to modulated and rough surfaces


  Correlation functions are sensitive to the presence of a boundary. Surface
modulations give rise to modified near surface correlations, which can be
measured by scattering probes. To determine these correlations, we develop a
perturbative calculation in deformations in height from a flat surface. The
results, combined with a renormalization group around four dimensions, are also
used to predict critical behavior near a self-affinely rough surface. We find
that a large enough roughness exponent can modify surface critical behavior.

</DOC>
<DOC>
<DOCNO> 99434 </DOCNO>
A Generalized Torelli Theorem


  Given a smooth projective curve $C$ of genus $g$ over the complex numbers,
Torelli's thoerem asserts that the pair $(J(C),W^{g-1})$ determines $C$, where
$W^{g-1}$ is an image of the $g-1$st symmetric power of $C$ inside the Jacobian
under an Abel-Jacobi map. We show that the theorem holds with $g-1$ replaced by
an integer $d$ in the range $1\le d\le g-1$.

</DOC>
<DOC>
<DOCNO> 150865 </DOCNO>
Instanton Calculus, Topological Field Theories and N=2 Super Yang-Mills


  The results obtained by Seiberg and Witten for the low-energy Wilsonian
effective actions of N=2 supersymmetric theories with gauge group SU(2) are in
agreement with instanton computations carried out for winding numbers one and
two. This suggests that the instanton saddle point saturates the
non-perturbative contribution to the functional integral. A natural framework
in which corrections to this approximation are absent is given by the
topological field theory built out of the N=2 Super Yang-Mills theory. After
extending the standard construction of the Topological Yang-Mills theory to
encompass the case of a non-vanishing vacuum expectation value for the scalar
field, a BRST transformation is defined (as a supersymmetry plus a gauge
variation), which on the instanton moduli space is the exterior derivative. The
topological field theory approach makes the so-called "constrained instanton"
configurations and the instanton measure arise in a natural way. As a
consequence, instanton-dominated Green's functions in N=2 Super Yang-Mills can
be equivalently computed either using the constrained instanton method or
making reference to the topological twisted version of the theory. We
explicitly compute the instanton measure and the contribution to $u=<\Tr
\phi^2>$ for winding numbers one and two. We then show that each
non-perturbative contribution to the N=2 low-energy effective action can be
written as the integral of a total derivative of a function of the instanton
moduli. Only instanton configurations of zero conformal size contribute to this
result. Finally, the 8k-dimensional instanton moduli space is built using the
hyperkahler quotient procedure, which clarifies the geometrical meaning of our
approach.

</DOC>
<DOC>
<DOCNO> 100402 </DOCNO>
Formulas of Verlinde type for non-simply connected groups


  We derive Verlinde's formula from the fixed point formula for loop groups
proved in the companion paper "A fixed point formula for loop group actions",
and extend it to compact, connected groups that are not necessarily
simply-connected.

</DOC>
<DOC>
<DOCNO> 70932 </DOCNO>
A fresh look at diffractive $J/\psi$ photoproduction at HERA, with


  We quantify perturbative and non-perturbative QCD effects in the exclusive
$J/\psi$-photoproduction cross section, and in the shrinkage of the
differential cross section with respect to momentum transfer, $t$. We predict
that in the high energy THERA region there will always be a significant
contribution to this process that rises quickly with energy. This implies that
the taming of the rise of the cross section with energy, due to both the
expansion of spatially-small fluctuations in the photon and to higher twist
effects, is rather gradual.

</DOC>
<DOC>
<DOCNO> 116863 </DOCNO>
Collector Failures on 350 MHz, 1.2 MW CW Klystrons at the Low Energy


  We are currently operating the front end of the accelerator production of
tritium (APT) accelerator, a 7 MeV radio frequency quadrapole (RFQ) using
three, 1.2 MW CW klystrons. These klystrons are required and designed to
dissipate the full beam power in the collector. The klystrons have less than
1500 operational hours. One collector has failed and all collectors are
damaged. This paper will discuss the damage and the difficulties in diagnosing
the cause. The collector did not critically fail. Tube operation was still
possible and the klystron operated up to 70% of full beam power with excellent
vacuum. The indication that finally led us to the collector failure was
variable emission. This information will be discussed. A hydrophonic system was
implemented to diagnose collector heating. The collectors are designed to allow
for mixed-phase cooling and with the hydrophonic test equipment we are able to
observe: normal, single-phase cooling, mixed-phase cooling, and a hard boil.
These data will be presented. The worst case beam profile from a collector
heating standpoint is presented. The paper will also discuss the steps taken to
halt the collector damage on the remaining 350 MHz klystrons and design changes
that are being implemented to correct the problem.

</DOC>
<DOC>
<DOCNO> 84406 </DOCNO>
Self force on particle in orbit around a black hole


  We study the self force acting on a scalar charge in uniform circular motion
around a Schwarzschild black hole. The analysis is based on a direct
calculation of the self force via mode decomposition, and on a regularization
procedure based on Ori's mode-sum regularization prescription. We find the four
self-force at arbitrary radii and angular velocities (both geodesic and
non-geodesic), in particular near the black hole, where general-relativistic
effects are strongest, and for fast motion. We find the radial component of the
self force to be repulsive or attractive, depending on the orbit.

</DOC>
<DOC>
<DOCNO> 9629 </DOCNO>
Synergetic theory for jamming transition in traffic flow


  The theory of a jamming transition is proposed for the homogeneous
car-following model within the framework of Lorenz scheme. We represent a
jamming transition as a result of the spontaneous deviations of headway and
velocity that is caused by the acceleration/braking rate to be higher than the
critical value. The stationary values of headway and velocity deviations, and
time of acceleration/braking are derived as functions of control parameter
(time needed for car to take the characteristic velocity).

</DOC>
<DOC>
<DOCNO> 121872 </DOCNO>
Disk-Jet Connection in the Microquasar GRS 1915+105 and IR and Radio


  We present evidence of a direct accretion disk-jet connection in the Galactic
microquasar GRS 1915+105 based on our analysis of RXTE/PCA data with a
``spike'' in X-ray light curves. We find that the radio emission increases as
the hardness ratio increases during the low hard state. We suggest that the
``spike'' which separates the dips with hard and soft spectra marks the
beginning of the burst phase when the luminosity of the soft X-rays (5-15 keV)
increases by a large factor (~ 10). This produces a major ejection episode of
the synchrotron - emitting plasma termed as ``baby jets'' which are associated
with infrared (IR) and radio flares of about half an hour period widely
reported in the literature. Subsequent short but frequent soft dips produce
overlapping faint flares which result in an enhanced level of quasi-steady
emission. We discuss the dissipation of accretion energy in the inner part of
the disk in terms of a comptonising cloud and the escaping mass which produces
synchrotron radiation. We discuss the differences between ``baby jets'' and
relativistic radio jets and especially investigate their signatures in X-rays.
Our results support the relativistic jet model with quasi-continuous mass
ejection and strong variations in the jet speeds required for the formation of
strong internal shocks to continuously accelerate the particles.

</DOC>
<DOC>
<DOCNO> 70955 </DOCNO>
Semileptonic form factors - a model-independent approach


  We demonstrate that the B->D(*) l nu form factors can be accurately predicted
given the slope parameter rho^2 of the Isgur-Wise function. Only weak
assumptions, consistent with lattice results, on the wavefunction for the light
degrees of freedom are required to establish this result. We observe that the
QCD and 1/m_Q corrections can be systematically represented by an effective
Isgur-Wise function of shifted slope. This greatly simplifies the analysis of
semileptonic B decay. We also investigate what the available semileptonic data
can tell us about lattice QCD and Heavy Quark Effective Theory. A rigorous
identity relating the form factor slope difference rho_D^2-rho_A1^2 to a
combination of form factor intercepts is found. The identity provides a means
of checking theoretically evaluated intercepts with experiment.

</DOC>
<DOC>
<DOCNO> 10087 </DOCNO>
Multi-Choice Minority Game


  The generalization of the problem of adaptive competition, known as the
minority game, to the case of $K$ possible choices for each player is
addressed, and applied to a system of interacting perceptrons with input and
output units of the type of $K$-states Potts-spins. An optimal solution of this
minority game as well as the dynamic evolution of the adaptive strategies of
the players are solved analytically for a general $K$ and compared with
numerical simulations.

</DOC>
<DOC>
<DOCNO> 99289 </DOCNO>
Derived categories for the working mathematician


  It is becoming increasingly difficult for geometers and even physicists to
avoid papers containing phrases like `triangulated category', not to mention
derived functors. I will give some motivation for such things from algebraic
geometry, and show how the concepts are already familiar from topology. This
gives a natural and simple way to look at cohomology and other scary concepts
in homological algebra like Ext, Tor, hypercohomology and spectral sequences.

</DOC>
<DOC>
<DOCNO> 12445 </DOCNO>
Magnetization reversal in a "quasi" single domain magnetic grain: a new


  Magnetization reversal in a fine ferromagnetic grain is simulated for the
case of an instantaneously applied reversal magnetic field. The Hamiltonian of
the system contains the exchange interaction, the uniaxial anisotropy, the
Zeeman energy and the dipole-dipole interactions. A cubic grain is discretized
into 64 cubic subgrains and the coupled gyromagnetic equations of motion are
solved without phenomenological damping. A new scheme to solve these equations
is developed that utilizes only two variables per sub-cube magnetization and
strictly conserves the absolute magnitude. The initial stage of reversal is
uniform rotation followed by a nonlinear excitation of nonuniform magnetic
oscillations driven by this uniform mode. An excess of the initial Zeeman
energy is transformed into nonlinear spin waves, allowing the average
magnetization to substantially reverse. The process of magnetization reversal
in fine quasi-single-domain grain exhibits general features of Hamiltonian wave
systems with nonlinear diffusion. This nonlinear diffusion is forbidden for
either a strong reversal field and/or a small grain size.

</DOC>
<DOC>
<DOCNO> 70100 </DOCNO>
Chiral Transition and Baryon-number Susceptibility


  We discuss the baryon-number susceptibility $\chi_B$ and related topics which
include the density fluctuations around the critical point of the chiral
transition at finite temperature $T$ and baryon density $\rho_B$.
Phenomenological implications of the density fluctuations near the first-order
chiral transition at finite density are also discussed.

</DOC>
<DOC>
<DOCNO> 120900 </DOCNO>
Near-Infrared Spectroscopy of Two Galaxies at z=2.3 and z=2.9: New


  This study presents Keck optical and infrared spectroscopy of the rest-frame
ultraviolet and optical emission lines in two Lyman alpha emitting galaxies at
z>2. These data provide insight on the evolution of fundamental galaxy scaling
relations at early epochs, especially the luminosity-velocity and
luminosity-metallicity relations. Lynx 2-9691 exhibits extended [O III]
emission over a diameter of >28 kpc, reminiscent of the Lyman alpha nebulae
discovered near Lyman-drop galaxies [Steidel et al 2000]. The ratios of strong
nebular emission lines indicate sub-solar oxygen abundances in the range
8.2<12+log(O/H)<8.8 (Z = 0.25-0.95 Z_sun). Interestingly, Galactic metal-rich
globular clusters have similar metallicities, consistent with the idea that we
could be seeing the formation of galaxies like the Milky Way at $z\sim3$. The
measured gas phase oxygen abundances are >4-10 times higher than the Z < 0.1
Z_sun metallicities found in damped Lyman alpha (DLA) absorbers at similar
redshifts, indicating that DLA systems trace different environments than the
vigorously star-forming objects observed here. Star-forming galaxies at
$z\sim3$ are 2-4 magnitudes more luminous than local spiral galaxies of similar
metallicity, and thus, are offset from the local luminosity-metallicity
relation. Their kinematic linewidths are sigma_v=65-130 km/s, making this
sample 1-3 magnitudes more luminous than local galaxies of similar linewidth
and mass. [Abridged]

</DOC>
<DOC>
<DOCNO> 150961 </DOCNO>
CP violation including universal one-loop corrections and heterotic


  CP violation by soft supersymmetry-breaking terms in orbifold
compactifications is investigated. We include the universal part of the
moduli-dependent threshold corrections in the construction of the
non-perturbative effective potential due to gaugino-condensation. This allows
interpolation of the magnitude of CP violating phases between the weakly and
strongly coupled regimes. We find that the universal threshold corrections have
a large effect on the CP violating phases in the weakly coupled regime.

</DOC>
<DOC>
<DOCNO> 100672 </DOCNO>
Study of the formal CR reflection mapping


  Corollary: Two germs of minimal real analytic CR-generic manifolds are
formally equivalent if and only if they are biholomorphic.

</DOC>
<DOC>
<DOCNO> 121263 </DOCNO>
The Star Clusters in the Starburst Irregular Galaxy NGC 1569


  We examine star clusters in the irregular, starburst galaxy NGC 1569 from HST
images. In addition to the two known super star clusters, we identify 45 other
clusters that are compact but resolved. Integrated UVI colors of the clusters
span a large range, and suggest that ages range from 3 Myrs to 1 Gyr. However,
most of the clusters were formed at the tail end of the recent starburst.
Numerous clusters in addition to the know super star clusters are similar in
luminosity to a small globular cluster. We examined the radial surface
brightness of four of the clusters. Their half-light radii and core radii are
in the range observed in present-day globular clusters. Therefore, conditions
that produced the recent starburst have also been those necessary for producing
compact, bright star clusters.
  We examine resolved stars in the outer parts of the two super star clusters.
Cluster A is dominated by bright blue stars with a small population of red
supergiants. Sub-components A1 and A2 have similar colors and a two-dimensional
color map does not offer evidence that one component is dominated by red
supergiants and the other not. The contradiction of the presence of red super-
giants with Wolf-Rayet stars may instead not be a contradiction at all since
there coexistence in a coeval population is not inconsistent with the evolution
of massive stars. Cluster B is dominated by red supergiants, and this is
confirmed by the presence of the stellar CO absorption feature in an integrated
spectrum. The various age indicators are consistent with a picture in which
cluster B is of order 10--20 Myrs old, and cluster A is >4-5 Myrs old.

</DOC>
<DOC>
<DOCNO> 116851 </DOCNO>
Reconstruction of Initial Beam Conditions at the Exit of the DARHT II


  We consider a technique to determine the initial beam conditions of the DARHT
II Accelerator by measuring the beam size under three different magnetic
transport settings. This may be time gated to resolve the parameters as a
function of time within the 2000 nsec pulse. This technique leads to three
equations in three unknowns with solution giving the accelerator exit beam
radius, tilt and emittance. We find that systematic errors cancel and so are
not a problem in unfolding the initial beam conditions. Random uncorrelated
shot to shot errors can be managed by one of three strategies: 1) make the
transport system optically de-magnifying; 2) average over many individual
shots; or 3) make the random uncorrelated shot to shot errors sufficiently
small. The high power of the DARHT II beam requires that the beam transport
system leading to a radius measuring apparatus be optically magnifying. This
means that the shot to shot random errors must either be made small (less than
about 1%) or that we average each of the three beam radius determinations over
many individual shots.

</DOC>
<DOC>
<DOCNO> 102687 </DOCNO>
Micro-support and Cauchy problem for temperate solutions of regular


  Let $X$ be a complex manifold, $V$ a smooth involutive submanifold of $T^*X$,
$\cal M$ a microdifferential system regular along $V$, and $F$ an
$\mathbb{R}$-constructible sheaf on $X$.
  The complex of temperate microfunction solutions of $\cal M$ associated with
$F$ is now well understood. In this paper we study the temperate case and give
a bound to the micro-support of the temperate microfunction solution sheaves
and solve the Cauchy problem under suitable hyperbolicity conditions.

</DOC>
<DOC>
<DOCNO> 69232 </DOCNO>
Relic Abundances and the Boltzmann Equation


  I discuss the validity of the quantum Boltzmann equation for the calculation
of WIMP relic densities.

</DOC>
<DOC>
<DOCNO> 169963 </DOCNO>
A study of the consistency between noncommutative quantum mechanics and


  A demonstration is given that the simplest model of quantum mechanics
formulated on a plane non-commutative geometry endowed with a Galilean symmetry
group in which the position and linear momentum-variable commutators are first
order in the dynamical variables (and thus constitute a true Lie algebra) is
incompatible with the hypothesis of spacial isotropy.

</DOC>
<DOC>
<DOCNO> 121302 </DOCNO>
A Model of Void Formation


  We introduce a simple model for the formation of voids. In this model the
underdensity of galaxies in voids is the product of two factors. The first
arises from a gravitational expansion of the negative density perturbation. The
second is due to biasing: galaxies are less likely to form in an underdense
region. One feature of the model is an upper cutoff in void sizes. We calculate
the volume filling factor of characteristic voids for different CDM models and
find that our formation model points to $\Lambda$CDM models as preferred models
of the power spectrum. A natural consequence of our model is that the
underdensity of the dark matter inside voids is smaller than the galaxy
underdensity.

</DOC>
<DOC>
<DOCNO> 68095 </DOCNO>
Emission of light mesons directly from the surface of quark-gluon plasma


  On the basis of hydrodynamic model of evolution we consider emission of
lightest (\pi,K,\eta,\rho,\omega,K^*) mesons directly from the surface of
quark-gluon plasma, created in the heavy ion collision, with accounting of
their absorption by surrounding hadronic gas. We evaluate upper and lower
limits on yields of these direct mesons in Pb+Pb collisions at SpS, RHIC and
LHC energies, and find, that even in the case of the lowest yield, direct K,
\eta and heavier mesons dominate over freeze-out ones at soft p_t (p_t < 0.5
GeV/c). This leads to enhancement of the low p_t production of these mesons
which hardly can be explained within pure hadronic gas scenario, and can be
considered as quark-gluon plasma signature.

</DOC>
<DOC>
<DOCNO> 70863 </DOCNO>
A Monte Carlo Study of the Dynamical-Flucautation Property of the


  A study of the dynamical fluctuation property of jets is carried out using
Monte Carlo method. The results suggest that, unlike the average properties of
the hadronic system inside jets, the anisotropy of dynamical fluctuations in
these systems changes abruptly with the variation of the cut parameter $\yct$.
A transition point exists, where the dynamical fluctuations in the hadronic
system inside jet behave like those in soft hadronic collisions, i.e. being
circular in the transverse plan with repect to dynamical fluctuations. This
finding obtained from Jetset and Herwig Monte Carlo is encouraged to be checked
by experiments.

</DOC>
<DOC>
<DOCNO> 151840 </DOCNO>
Some Remarks about Duality, Analytic Torsion and Gaussian Integration in


  From a path integral point of view (e.g. \cite{Q98}) physicists have shown
how {\it duality} in antisymmetric quantum field theories on a closed
space-time manifold $M$ relies in a fundamental way on Fourier Transformations
of formal infinite-dimensional volume measures. We first review these facts
from a measure theoretical point of view, setting the importance of the Hodge
decomposition theorem in the underlying geometric picture, ignoring the local
symmetry which lead to degeneracies of the action. To handle these degeneracies
we then apply Schwarz's Ansatz showing how duality leads to a factorization of
the analytic torsion of $M$ in terms of the partition functions associated to
degenerate "dual" actions, which in the even dimensional case corresponds to
the identification of these partition functions.

</DOC>
<DOC>
<DOCNO> 80979 </DOCNO>
An investigation into the Fermilab approach to heavy quarks on the


  We use a space-time asymmetric O(a) improved fermion action and fix the
asymmetry non-perturbatively to restore the relativistic dispersion relation.
We compute spectra and matrix elements of quarkonia and heavy-light mesons and
compare with results obtained using a symmetric action with the Fermilab
interpretation i.e. that the physics of heavy lattice quarks depends solely on
their kinetic mass. We provide additional evidence to support this.

</DOC>
<DOC>
<DOCNO> 12354 </DOCNO>
Spectral function and conductivity in the normal state of the cuprates:


  We study the spectral function $A_k (\omega)$ and the optical conductivity
$\sigma_1 (\omega)$ for a system of fermions interacting with their collective
spin fluctuations (the spin-fermion model), and apply the results to optimally
doped cuprates in the normal state. We show that there is no qualitative
distinction between hot and cold regions in the
 Brillouin zone - in both cases, there exists a wide range of frequencies where
the width of the peak in $A_k (\omega)$ scales linearly with $\omega$. We
demonstrate that $\sigma_1 (\omega)$ is inversely linear in $\omega$ up to very
high frequencies. We argue that these results agree {\it quantitatively} with
the photoemission and optical data for $Bi2212$.

</DOC>
<DOC>
<DOCNO> 121126 </DOCNO>
Cluster galaxies: contribution to the arc statistics


  We present the results of a set of numerical simulations aiming at evaluating
the effects of cluster galaxies on the arc statistics. At this goal we use nine
different galaxy clusters obtained from N-body simulations. We mimic the
presence of a population of galaxies inside each cluster, trying to reproduce
the observed luminosity function and the spatial distribution. We compare the
statistical distributions of the properties of the gravitational arcs produced
by our clusters with and without galaxies. We find that the cluster galaxies do
not introduce perturbations strong enough to significantly change the number of
arcs and the distributions of the properties of long arcs.

</DOC>
<DOC>
<DOCNO> 80919 </DOCNO>
Magnetic condensation and confinement in lattice gauge theory


  We investigate Abelian monopoles and Abelian vortices condensation in finite
temperature SU(2) and SU(3) pure lattice gauge theories.

</DOC>
<DOC>
<DOCNO> 152296 </DOCNO>
Conformal Invariance and Quantum Aspects of Matter


  The vacuum sector of the Brans-Dicke theory is studied from the viewpoint of
a non-conformally invariant gravitational model. We show that, this theory can
be conformally symmetrized using an appropriate conformal transformation. The
resulting theory allows a particle interpretation, and suggests that the
quantum aspects of matter may be geometrized.

</DOC>
<DOC>
<DOCNO> 85662 </DOCNO>
Conservative General Relativistic Radiation Hydrodynamics in Spherical


  The description of general relativistic radiation hydrodynamics in spherical
symmetry is presented in natural coordinate choices. For hydrodynamics,
comoving coordinates are chosen, and the momentum phase space for the radiation
particles is described in comoving frame four momenta. We also investigate a
description of the momentum phase space in terms of particle impact parameter
and energy at infinity and derive a simple approximation to the general
relativistic Boltzmann equation. Further developed are, however, the exact
equations in comoving coordinates, because the description of the interaction
between matter and radiation particles is best described in the closely related
orthonormal basis comoving with the fluid elements. We achieve a conservative
and concise formulation of radiation hydrodynamics that is well suited for
numerical implementation by a variety of methods. The contribution of radiation
to the general relativistic jump conditions at shock fronts is discussed, and
artificial viscosity is consistently included in the derivations in order to
support approaches relying on this option.

</DOC>
<DOC>
<DOCNO> 120296 </DOCNO>
Space-VLBI observations of OH maser OH34.26+0.15: low interstellar


  We report on the first space-VLBI observations of the OH34.26+0.15 maser in
two main line OH transitions at 1665 and 1667 MHz. The observations involved
the space radiotelescope on board the Japanese satellite HALCA and an array of
ground radio telescopes. The map of the maser region and images of individual
maser spots were produced with an angular resolution of 1 milliarcsec which is
several times higher than the angular resolution available on the ground. The
maser spots were only partly resolved and a lower limit to the brightness
temperature 6x10^{12} K was obtained. The maser seems to be located in the
direction of low interstellar scattering, an order of magnitude lower than the
scattering of a nearby extragalactic source and pulsar.

</DOC>
<DOC>
<DOCNO> 151754 </DOCNO>
A remark on Schwarz's topological field theory


  The standard evaluation of the partition function $Z$ of Schwarz's
topological field theory results in the Ray--Singer analytic torsion. Here we
present an alternative evaluation which results in Z=1. Mathematically, this
amounts to a novel perspective on analytic torsion: it can be formally written
as a ratio of volumes of spaces of differential forms which is formally equal
to 1 by Hodge duality. An analogous result for Reidemeister combinatorial
torsion is also obtained.

</DOC>
<DOC>
<DOCNO> 11898 </DOCNO>
Bosonic and Fermionic Eigenstates for Generalized Sutherland Models


  We construct bosonic and fermionic eigenstates for the generalized Sutherland
models associated with arbitrary reduced root systems respectively, through
W-symmetrization and W-anti-symmetrization of Heckman-Opdam's nonsymmetric
Jacobi polynomials. Square norms of the nonsymmetric Heckman-Opdam polynomials
are evaluated from their Rodrigues formulae. The W-symmetrization and
W-anti-symmetrization of the nonsymmetric polynomials enable us to evaluate
square norms of bosonic and fermionic eigenstates for the generalized
Sutherland models.

</DOC>
<DOC>
<DOCNO> 8289 </DOCNO>
New Software for Measurements of the Anisotropic Resistivity by


  We present an overview of the capabilities of a new software developed for
use with multiterminal measurements. The program supports two configurations of
current and voltage contacts known in the parlance of the field as "flux
transformer" and " I$\|$c" geometries. The problem of instability of the
results obtained by the multiterminal method and the ways to overcome it is
also discussed.

</DOC>
<DOC>
<DOCNO> 9821 </DOCNO>
Lattice Boltzmann simulations of segregating binary fluid mixtures in


  We apply lattice Boltzmann method to study the phase separation of a
two-dimensional binary fluid mixture in shear flow. The algorithm can simulate
systems described by the Navier-Stokes and convection-diffusion equations. We
propose a new scheme for imposing the shear flow which has the advantage of
preserving mass and momentum conservation on the boundary walls without
introducing slip velocities. Our main results concern the presence of two
typical lenght scales in the phase separation process, corresponding to domains
with two different thicknesses. Our simulations at low viscosity confirm
previous results only valid in the limit of infinite viscosity.

</DOC>
<DOC>
<DOCNO> 150695 </DOCNO>
What does the string/gauge correspondence teach us about Wilson loops?


  In these lectures we describe the attempt to extract the expectation values
of Wilson loops from the string/gauge correspondence. We start with the
original calculation in $AdS_5$. It is then extended to the non-conformal
background of $D_p$ in the near horizon limit. We discuss the computation at
finite temperature. Supergravity models that admit confinement in 3d and 4d are
described. A theorem that determines the classical values of loops associated
with a generalized background is derived.In particular we determine sufficient
conditions for confining behavior. We then apply the theorem to various string
models including type 0 ones. We describe an attempt to go beyond the classical
string picture by incorporating quadratic quantum fluctuations. In particular
we address the BPS configuration of a single quark, the supersymmetric
determinant of $AdS_5\times S^$ and a setup that corresponds to a confining
gauge theory. We determine the form of the Wilson loop for actions that include
non trivial $B_{\mu\nu}$ field. The issue of an exact determination of the
value of the stringy Wilson loop is discussed. We end with a brief review of
the baryons from the string/gauge correspondence Lectures presented in the
``Advanced School on Supersymmetry in the theories of fields, strings and
branes'' Santiago de Compostela-99.

</DOC>
<DOC>
<DOCNO> 120140 </DOCNO>
Stellar Evolution with Rotation V: Changes in all the Outputs of Massive


  Grids of models for rotating stars are constructed in the range of 9 to 120
M$_{\odot}$ at solar metallicity. The following effects of rotation are
included: shellular rotation, new structure equations for non-conservative
case, surface distorsions, increase of mass loss with rotation, meridional
circulation and interaction with horizontal turbulence, shear instability and
coupling with thermal effects, advection and diffusion of angular momentum
treated in the non-stationary regime, transport and diffusion of the chemical
elements.
  Globally we find that for massive stars the effects of rotation have an
importance comparable to those of mass loss. For an average rotation, the
tracks in the HR diagram are modified like a moderate overshoot would do. In
general, an average rotation may increase the MS lifetime up to about 30 %; for
the helium-burning phase the effects are smaller and amount to at most 10 %.
  Rotation also brings significant surface He- and N-enhancements, they are
higher for higher masses and rotation.

</DOC>
<DOC>
<DOCNO> 71835 </DOCNO>
Left Hand Singularities, Hadron Form Factors and the Properties of the


  By applying analyticity and single channel unitarity we derive a new formula
which is useful to analyze the role of the left-hand singularities in hadron
form factors and in the determination of the resonance parameters. Chiral
perturbation theory is used to estimate the left-hand cut effects in $\pi\pi$
scattering processes. We find that in the IJ=11 channel the left-hand cut
effect is negligible and in the IJ=20 channel the phase shift is dominated by
the left-hand cut effect. In the IJ=00 channel the left-hand cut contribution
to the phase shift has the wrong sign comparing with the experimental data and
therefore it necessitates the $\sigma$ resonance. The new experimental results
from the E865 collaboration is crucial in reducing the uncertainty in the
determination of the mass and width of the $\sigma$ resonance within our
scheme.

</DOC>
<DOC>
<DOCNO> 12217 </DOCNO>
Tunneling of localized excitations: giant enhancement due to


  We consider the tunneling of localized excitations (many boson bound states)
in the presence of a bosonic bath. We show both analytically and numerically
that the bath influence results in a dramatical enhancement of the amplitude of
the excitation tunneling. The order of the bosonic flow in the course of the
tunneling process is obtained. On the background of the giant tunneling
enhancement we observe and describe additional resonant enhancement and {\sl
suppression} of tunneling due to avoided level crossings.

</DOC>
<DOC>
<DOCNO> 10168 </DOCNO>
The exchange energy in the local Airy gas approximation


  The Airy gas model of the edge electron gas is used to construct an
exchange-energy functional which is an alternative to those obtained in the
local density and generalized gradient approximations. Test calculations for
rare gas atoms, molecules, solids and surfaces show that the Airy gas
functional performs better than the local density approximation in all cases
and better than the generalized gradient approximation for solids and surfaces.

</DOC>
<DOC>
<DOCNO> 119552 </DOCNO>
Observational Constraints on the Theory of the IMF


  Observational constraints on the theory of the IMF are reviewed. These
observations include the new result that star formation is very rapid, usually
going from start to finish in only 1 or 2 dynamical times on a wide range of
scales. This result, combined with the observation that the IMF is independent
of cluster density over a factor of several hundred, implies that protostar
coagulation during orbital motions in a cloud are not important for the IMF:
there is not enough time. The observation that the IMF in individual clusters
is about the same as the IMF in whole galaxies implies that stars of all masses
form randomly in self-gravitating clouds of all masses. There cannot be a
sequence of stellar masses in a cluster, based on stirring or heating for
example, where the largest star that forms keeps increasing until the cloud is
destroyed. The uniformity of the IMF over time and space argues for a process
that is independent of specific properties of molecular clouds. This
uniformity, along with the common observation of young stars in hierarchical
clusters that resemble the structures of interstellar gas, suggests that the
IMF, at least in the power law range, is a by-product of turbulence. Detailed
physical processes may affect the turnover at low mass, but even this may have
a universal character arising from a combination of turbulence-induced
variations in the local cloud properties, and fragmentation in unstable cloud
pieces.

</DOC>
<DOC>
<DOCNO> 119496 </DOCNO>
Evidence for a high accretion rate as the defining parameter of


  X-ray spectral features which are unusually strong in many Narrow-Line
Seyfert galaxies are found to be consistent with reflection from strongly
ionized matter, providing further evidence of a high accretion rate in these
objects and offering a unique signature of that key parameter in future
observations.

</DOC>
<DOC>
<DOCNO> 40370 </DOCNO>
Hadron-hadron and hadron-nuclei collisions at high energies


  A brief review is made of the present situation of hadron-hadron and
hadron-nuclei total elastic and inelastic cross sections at high energies

</DOC>
<DOC>
<DOCNO> 151416 </DOCNO>
Dissipation and memory domains in the quantum model of brain


  We shortly review the dissipative quantum model of brain and its parametric
extension.

</DOC>
<DOC>
<DOCNO> 121354 </DOCNO>
Peculiar Extended X-ray Emission around the "Radio-Loud" Black Hole


  We present the discovery of peculiar extended X-ray emission around
1E1740.7-2942, a black hole candidate that is known to produce prominent,
persistent radio jets. The data was obtained with the High-Energy Transmission
Grating Spectrometer (HETGS) aboard the Chandra X-ray Observatory. The
zeroth-order image reveals an elongated feature about 3" in length that is
roughly perpendicular to the radio lobes (or jets). The feature is roughly
symmetric about the point source. It is spatially resolved in the long
direction but not in the short direction.
  The position of 1E1740.7-2942 was determined with a statistical accuracy of
\~0.06" in the right ascension and ~0.04" in the declination, thanks to
Chandra's unprecedented spatial resolution. It is about 0.6" from the radio
position but the difference is well within the uncertainty in the absolute
aspect solutions of the observation. The dispersed HETGS spectra of
1E1740.7-2942 show evidence for the presence of weak, narrow emission lines,
although the statistics are quite limited. We discuss possible origins of the
extended emission and the implications of the emission lines.

</DOC>
<DOC>
<DOCNO> 13550 </DOCNO>
Effects of nuclear spins on the coherent evolution of a phase qubit


  The role of nuclear spins in decoherence and dephasing of a solid state phase
qubit is investigated. Both effects of static spin environment and spin
polarization fluctuations in time are considered on the basis of non-Markovian
Langevin-Bloch equations. We find conditions when coupling of a phase qubit to
a bath of nuclear spins does not impair coherent evolution of the qubit.

</DOC>
<DOC>
<DOCNO> 40310 </DOCNO>
Measurements of F_2 and xF_3(nu)-xF_3(nubar) from CCFR nu_mu-Fe and


  We report on the extraction of the structure functions F_2 and Delta xF_3 =
xF_3(nu)-xF_3(nubar) from CCFR nu_mu-Fe and nubar_mu-Fe differential cross
sections. The extraction is performed in a physics model independent (PMI) way.
This first measurement of Delta xF_3, which is useful in testingmodels of heavy
charm production, is higher than current theoretical predictions. The ratio of
the F_2(PMI) values measured in nu_mu and nubar_mu scattering is in agreement
(within 5%) with the predictions of NLO PDFS using massive charm production
schemes, thus resolvin long-standing discrepancy between the two sets of data.

</DOC>
<DOC>
<DOCNO> 11287 </DOCNO>
Critical Behaviour in the Spin Fluctuations and Superfluid Density of


  We study the doping dependence of low frequency spin fluctuations and the
zero-temperature superfluid density of La$_{2-x}$Sr$_x$CuO$_4$ using the muon
spin relaxation ($\mu$SR) and ac-susceptibility techniques. Superconductivity
is found to coexist with low frequency spin fluctuations over a large region of
the superconducting phase diagram. The characteristic temperature of spin
fluctuations detected by $\mu$SR decreases with increasing $x$ and vanishes
above a critical doping $x_c\sim 0.19$. This value of $x_c$ coincides with the
doping at which the normal state pseudogap extrapolates to zero. The superfluid
density behaves in the opposite way to the low frequency spin fluctuations. It
increases with $x$ and becomes nearly doping-independent for $x>x_c$. These
results are consistent with predictions involving quantum criticality at $x_c$.

</DOC>
<DOC>
<DOCNO> 69444 </DOCNO>
One-loop fermion determinant with explicit chiral symmetry breaking


  We use a proper-time regularization to define the one-loop fermion
determinant for the case in which explicit chiral symmetry breaking takes
place. We show how to obtain the polynomial by which the standard definition of
lndetD needs to be modified in order to arrive at the fermion determinant whose
transformation properties are consistent with the general symmetry requirements
of the basic Lagrangian. As an example it is shown how the fundamental
symmetries and the explicit chiral symmetry breaking pattern associated with
the ENJL model are preserved in a consistent way.

</DOC>
<DOC>
<DOCNO> 12697 </DOCNO>
Persistence of Li Induced Kondo Moments in the Superconducting State of


  We measure the magnetic susceptibility nearby Li spinless impurities in the
superconducting phase of the high Tc cuprate YBaCuO. The induced moment which
was found to exist above Tc persists below Tc. In the underdoped regime, it
retains its Curie law below Tc. In contrast, near optimal doping, the large
Kondo screening observed above Tc (T_K=135 K) is strongly reduced below Tc as
expected theoretically when the superconducting gap develops. This moment still
extends essentially on its 4 near neighbour Cu, showing the persistence of AF
correlations in the superconducting state. A direct comparison with recent STM
results of Pan et al. is proposed.

</DOC>
<DOC>
<DOCNO> 70202 </DOCNO>
Interesting consequences of brane cosmology


  We discuss cosmology in four dimensions within a context of brane-world
scenario.Such models can predict chaotic inflation with very low reheat
temperature depending on the brane tension. We notice that the gravitino
abundance is different in the brane-world cosmology and by tuning the brane
tension it is possible to get extremely low abundance. We also study
Affleck-Dine baryogenesis in our toy model.

</DOC>
<DOC>
<DOCNO> 12383 </DOCNO>
Structure and dynamics of a model glass: influence of long-range forces


  We vary the amplitude of the long-range Coulomb forces within a classical
potential describing a model silica glass and study the consequences on the
structure and dynamics of the glass, via molecular dynamics simulations. This
model allows us to follow the variation of specific features such as the First
Sharp Diffraction Peak and the Boson Peak in a system going continuously from a
fragile (no Coulomb forces) to a strong (with Coulomb forces) glass. In
particular we show that the characteristic features of a strong glass
(existence of medium range order, bell-shaped ring size distribution, sharp
Boson peak) appear as soon as tetrahedral units are formed.

</DOC>
<DOC>
<DOCNO> 170115 </DOCNO>
Efficient Raman Sideband Generation in a Coherent Atomic Medium


  We demonstrate the efficient generation of Raman sidebands in a medium
coherently prepared in a dark state by continuous-wave low-intensity laser
radiation. Our experiment is performed in sodium vapor excited in $\Lambda $
configuration on the D$_{1}$ line by two laser fields of resonant frequencies
$\omega_{1}$ and $\omega_{2}$, and probed by a third field $% \omega_{3}$.
First-order sidebands for frequencies $\omega_{1}$, $\omega_{2}$ and up to the
third-order sidebands for frequency $\omega_{3}$ are observed. The generation
starts at a power as low as 10 microwatt for each input field. Dependencies of
the intensities of both input and generated waves on the frequency difference
($\omega_{1}-\omega_{2}$), on the frequency $\omega_{3}$ and on the optical
density are investigated.

</DOC>
<DOC>
<DOCNO> 85293 </DOCNO>
Relativistic theory for time and frequency transfer to order c^{-3}


  This paper is motivated by the current development of several space missions
(e.g. ACES on International Space Station) that will fly on Earth orbit laser
cooled atomic clocks, providing a time-keeping accuracy of the order of
5~10^{-17} in fractional frequency. We show that to such accuracy, the theory
of frequency transfer between Earth and Space must be extended from the
currently known relativistic order 1/c^2 (which has been needed in previous
space experiments such as GP-A) to the next relativistic correction of order
1/c^3. We find that the frequency transfer includes the first and second-order
Doppler contributions, the Einstein gravitational red-shift and, at the order
1/c^3, a mixture of these effects. As for the time transfer, it contains the
standard Shapiro time delay, and we present an expression also including the
first and second-order Sagnac corrections. Higher-order relativistic
corrections, at least O(1/c^4), are numerically negligible for time and
frequency transfers in these experiments, being for instance of order 10^{-20}
in fractional frequency. Particular attention is paid to the problem of the
frequency transfer in the two-way experimental configuration. In this case we
find a simple theoretical expression which extends the previous formula (Vessot
et al. 1980) to the next order 1/c^3. In the Appendix we present the detailed
proofs of all the formulas which will be needed in such experiments.

</DOC>
<DOC>
<DOCNO> 12156 </DOCNO>
Highly anisotropic commensurability oscillations in two-dimensional


  Measurements of commensurability oscillations in GaAs/AlGaAs two-dimensional
(2D) hole systems grown on GaAs (311)A substrates reveal a remarkable
anisotropy: the amplitude of the measured commensurability oscillations along
the [$\bar{2}$33] direction is about 100 times larger than along [01$\bar{1}$].
For 2D electron systems at similar interfaces, however, we observe nearly
isotropic oscillations, suggesting that the anomalous anisotropy is intrinsic
to GaAs 2D holes at the (311)A interface.

</DOC>
<DOC>
<DOCNO> 85464 </DOCNO>
Sum-Over-Histories Quantization of Relativistic Particle


  Sum-over-histories quantization of particle-like theory in curved space is
discussed. It is reviewed that the propagator satisfies the Schrodinger
equation respective wave equation with a Laplace-like operator. The exact
dependence of the operator on the choice of measure is shown.
  Next, modifications needed for a manifold with a boundary are introduced, and
the exact form of the equation for the propagator is derived. It is shown that
the Laplace-like operator contains some distributional terms localized on the
boundary. These terms induce proper boundary conditions for the propagator.
This choice of boundary conditions is explained as a consequence of a
measurement of particles on the boundary.
  The interaction with sources inside of the domain and sources on the boundary
is also discussed.

</DOC>
<DOC>
<DOCNO> 151891 </DOCNO>
On the short-distance structure of irrational non-commutative gauge


  As shown by Hashimoto and Itzhaki in hep-th/9911057, the perturbative degrees
of freedom of a non-commutative Yang-Mills theory (NCYM) on a torus are
quasi-local only in a finite energy range. Outside that range one may resort to
a Morita equivalent (or T-dual) description appropriate for that energy. In
this note, we study NCYM on a non-commutative torus with an irrational
deformation parameter $\theta$. In that case, an infinite tower of dual
descriptions is generically needed in order to describe the UV regime. We
construct a hierarchy of dual descriptions in terms of the continued fraction
approximations of $\theta$. We encounter different descriptions depending on
the level of the irrationality of $\theta$ and the amount of non-locality
tolerated. The behavior turns out to be isomorphic to that found for the phase
structure of the four-dimensional Villain $Z_N$ lattice gauge theories, which
we revisit as a warm-up. At large 't Hooft coupling, using the AdS/CFT
correspondance, we find that there are domains of the radial coordinate $U$
where no T-dual description makes the derivative expansion converge. The radial
direction obtains multifractal characteristics near the boundary of AdS.

</DOC>
<DOC>
<DOCNO> 12715 </DOCNO>
Interference and interaction effects in multi-level quantum dots


  Using renormalization group techniques, we study spectral and transport
properties of a spinless interacting quantum dot consisting of two levels
coupled to metallic reservoirs. For strong Coulomb repulsion $U$ and an applied
Aharonov-Bohm phase $\phi$, we find a large direct tunnel splitting
$|\Delta|\sim (\Gamma/\pi)|\cos(\phi/2)|\ln(U/\omega_c)$ between the levels of
the order of the level broadening $\Gamma$. As a consequence we discover a
many-body resonance in the spectral density that can be measured via the
absorption power. Furthermore, for $\phi=\pi$, we show that the system can be
tuned into an effective Anderson model with spin-dependent tunneling.

</DOC>
<DOC>
<DOCNO> 118056 </DOCNO>
Limits on Hot Intracluster Gas Contributions to the Tenerife Temperature


  We limit the contribution of the hot intracluster gas, by means of the
Sunyaev-Zel'dovich effect, to the temperature anisotropies measured by the
Tenerife experiment. The data is cross-correlated with maps generated from the
ACO cluster catalogue, the ROSAT PSPC catalogue of clusters of galaxies, a
catalogue of superclusters and the HEAO 1 A-1 map of X-ray sources. There is no
evidence of contamination by such sources at an rms level of $\sim 8\mu$K at
99% confidence level at $5^o$ angular resolution. We place an upper limit on
the mean Comptonization parameter of $ y \le 1.5\times 10^{-6}$ at the same
level of confidence. These limits are slightly more restrictive than those
previously found by a similar analysis on the COBE/DMR data and indicate that
most of the signal measured by Tenerife is cosmological.

</DOC>
<DOC>
<DOCNO> 120175 </DOCNO>
Confidence levels of evolutionary synthesis models


  The stochastic nature of the IMF in young stellar clusters implies that
clusters of the same mass and age do not present the same unique values of
their observed parameters. Instead they follow a distribution. We address the
study of such distributions, parameterised in terms of their confidence limits,
in evolutionary synthesis models. These confidence limits can be understood as
the inherent uncertainties of the synthesis models. Here we concentrate on some
parameters such as EW(Hb) in emission. For instance, we show that for a cluster
where 10^5 Mo have been transformed into stars, the dispersion of EW(Hb) is
about 18% within the 90% confidence levels at ages between 3.5 and 5 Myrs.

</DOC>
<DOC>
<DOCNO> 40007 </DOCNO>
Correlations of Solar Neutrino Observables for SNO


  Neutrino oscillation scenarios predict correlations, and zones of avoidance,
among measurable quantities such as spectral energy distortions, total fluxes,
time dependences, and flavor content. The comparison of observed and predicted
correlations will enhance the diagnostic power of solar neutrino experiments. A
general test of all presently-allowed (two neutrino) oscillation solutions is
that future measurements must yield values outside the predicted zones of
avoidance. To illustrate the discriminatory power of the simultaneous analysis
of multiple observables, we map currently allowed regions of neutrino masses
and mixing angles onto planes of quantities measurable with the Sudbury
Neutrino Observatory (SNO). We calculate the correlations that are predicted by
vacuum and MSW (active and sterile) neutrino oscillation solutions that are
globally consistent with all available neutrino data. We derive approximate
analytic expressions for the dependence of individual observables and specific
correlations upon neutrino oscillations parameters. We also discuss the
prospects for identifying the correct oscillation solution using multiple SNO
observables.

</DOC>
<DOC>
<DOCNO> 39942 </DOCNO>
New Phenomena II: Recent Results from the Fermilab Tevatron


  The CDF and D\O collaborations continue to search for new physics using more
than 100~pb$^{-1}$ of \xxbar{p} collisions at $\sqrt{s}=1.8$ TeV collected at
the Fermilab Tevatron. We present recent results from both experiments on
R-parity violating Supersymmetry and $Z'$/Technicolor production with $ee$ and
\xxbar{t} final states. In addition we introduce Sherlock, a new
quasi-model-independent search strategy.

</DOC>
<DOC>
<DOCNO> 99537 </DOCNO>
Finiteness theorems for nonnegatively curved vector bundles


  We prove several finiteness theorems for the normal bundles to souls in
nonnegatively curved manifolds. More generally, we obtain finiteness results
for open Riemannian manifolds whose topology is concentrated on compact domains
of ``bounded geometry''.

</DOC>
<DOC>
<DOCNO> 150837 </DOCNO>
3-point functions of universal scalars in maximal SCFTs at large N


  We compute all 3-point functions of the ``universal'' scalar operators
contained in the interacting, maximally supersymmetric CFTs at large N by using
the AdS/CFT correspondence. These SCFTs are related to the low energy
description of M5, M2 and D3 branes, and the common set of universal scalars
corresponds through the AdS/CFT relation to the fluctuations of the metric and
the magnetic potential along the internal manifold. For the interacting (0,2)
SCFT_6 at large N, which is related to M5 branes, this set of scalars is
complete, while additional non-universal scalar operators are present in the
d=4, N=4 super Yang-Mills theory and in the N=8 SCFT_3, related to D3 and M2
branes, respectively.

</DOC>
<DOC>
<DOCNO> 8570 </DOCNO>
Dissipative Particle Dynamics with Energy Conservation: Dynamic and


  Simulation results of the thermal conductivity ${\cal L}$ of Dissipative
Particle Dynamics model with Energy Conservation (DPDE) are reported. We also
present an analysis of the transport equations and the transport coefficients
for DPDE based on a local equilibrium approximation. This approach is valid
when the particle-particle thermal conductivity $\lambda$ and the friction
coefficient $\zeta$ are large. A qualitative derivation of the scaling form of
the kinetic contribution of the transport of energy is derived, yielding two
different forms for the kinetic contribution to the heat transport, depending
on the value of $\lambda$. We find agreement between the theoretically
predicted value for ${\cal L}$ and the simulation results, for large $\lambda$
and many particles interacting at one time. Significant differences are found
for small number of interacting particles, even with large $\lambda$. For
smaller values of $\lambda$, the obtained macroscopic thermal conductivity is
dominated by diffusive transport, in agreement with the proposed scaling form.

</DOC>
<DOC>
<DOCNO> 12988 </DOCNO>
Critical behavior of the massless free field at the depinning transition


  We consider the d-dimensional massless free field localized by a
delta-pinning of strength e. We study the asymptotics of the variance of the
field, and of the decay-rate of its 2-point function, as e goes to zero, for
general Gaussian interactions. Physically speaking, we thus rigorously obtain
the critical behavior of the transverse and longitudinal correlation lengths of
the corresponding d+1-dimensional effective interface model in a non-mean-field
regime. We also describe the set of pinned sites at small e, for a broad class
of d-dimensional massless models.

</DOC>
<DOC>
<DOCNO> 99378 </DOCNO>
Non-linear connections on phase space and the Lorentz force law


  The equations of parallel transport for a non-linear connection on phase
space are examined. It is shown that, for a free-particle Lagrangian, the
connection term first-order in momentum reproduces the geodesic equation of
General Relativity and the term zeroth-order in the momentum reproduces the
Lorentz electromagnetic force law. Hence from one mathematical expression, a
non-linear parallel transport equation, one can derive the interaction laws for
both the gravitational and electromagnetic forces. These equations are free of
the difficulties associated with formalism of Weyl, which forms the basis for
the theory of Yang and Mills.

</DOC>
<DOC>
<DOCNO> 150341 </DOCNO>
On the Schrodinger Equation for the Minisuperspace Models


  We obtain a time-dependent Schrodinger equation for the Friedmann - Robertson
- Walker (FRW) model interacting with a homogeneous scalar matter field. We
show that for this purpose it is necesary to include an additional action
invariant under the reparametrization of time. The last one does not change the
equations of motion of the system, but changes only the constraint which at the
quantum level becomes time-dependent Schrodinger equation. The same procedure
is applied to the supersymmetric case and the supersymmetric quantum
constraints are obtained, one of them is a square root of the Schrodinger
operator.

</DOC>
<DOC>
<DOCNO> 122382 </DOCNO>
X-ray Luminosity Functions of Young Stars in Taurus-Auriga-Perseus


  X-ray luminosity functions (XLF) are frequently used to assess the properties
of the X-ray emission from a given sample of stars, and particularly important
for a comparison of different groups of stars. I present the results from a
detailed analysis of the XLF of pre-main sequence T Tauri Stars in
Taurus-Auriga and young main-sequence objects (represented by the Pleiades and
Hyades cluster). The study is based on the ROSAT public archive. Various
possible biases related to the sample selection are described, and their
influence on the luminosity distributions is discussed.

</DOC>
<DOC>
<DOCNO> 100267 </DOCNO>
Connection Between Type A and E Factorizations and Construction of


  Recently, we introduced a new class of symmetry algebras, called satellite
algebras, which connect with one another wavefunctions belonging to different
potentials of a given family, and corresponding to different energy
eigenvalues. Here the role of the factorization method in the construction of
such algebras is investigated. A general procedure for determining an so(2,2)
or so(2,1) satellite algebra for all the Hamiltonians that admit a type E
factorization is proposed. Such a procedure is based on the known relationship
between type A and E factorizations, combined with an algebraization similar to
that used in the construction of potential algebras. It is illustrated with the
examples of the generalized Morse potential, the Rosen-Morse potential, the
Kepler problem in a space of constant negative curvature, and, in each case,
the conserved quantity is identified. It should be stressed that the method
proposed is fairly general since the other factorization types may be
considered as limiting cases of type A or E factorizations.

</DOC>
<DOC>
<DOCNO> 178508 </DOCNO>
Fragment Formation and Phase Transitions in Heavy Ion Collisions


  We investigate the thermodynamical properties of nuclear matter in heavy ion
collisions, in particular with respect to questions of thermodynamical
instability, phase transitions and fragmentation. For this we analyze results
of relativistic transport calculations of Au+Au collisons at intermediate
energies, separately for spectator and participant matter. On one hand, we
determine local thermodynamical variables from the analysis of the local
momentum distribution; on the other, we analyze fragment energy spectra in a
blast model scenario. We find that the spectator represents an instable,
equilibrized fragmenting source, while in the participant no such common source
can be identified. Our results compare well with experimental determinations of
temperatures and flow velocities.

</DOC>
<DOC>
<DOCNO> 70434 </DOCNO>
Quark-gluon vertex in arbitrary gauge and dimension


  One-loop off-shell contributions to the quark-gluon vertex are calculated, in
an arbitrary covariant gauge and in arbitrary space-time dimension, including
quark-mass effects. It is shown how one can get results for all on-shell limits
of interest directly from the off-shell expressions. In order to demonstrate
that the Ward-Slavnov-Taylor identity for the quark-gluon vertex is satisfied,
we have also calculated the corresponding one-loop contribution involving the
quark-quark-ghost-ghost vertex.

</DOC>
<DOC>
<DOCNO> 70105 </DOCNO>
Geometric Bounds on Kaluza-Klein Masses


  We point out geometric upper and lower bounds on the masses of bosonic and
fermionic Kaluza-Klein excitations in the context of theories with large extra
dimensions. The characteristic compactification length scale is set by the
diameter of the internal manifold. Based on geometrical and topological
considerations, we find that certain choices of compactification manifolds are
more favoured for phenomenological purposes.

</DOC>
<DOC>
<DOCNO> 100029 </DOCNO>
Square numbers, spanning trees and invariants of achiral knots


  We examine and partially confirm some questions on properties of the the
Alexander and HOMFLY polynomial of achiral knots. In particular we show that
determinants of achiral knots are exactly the odd numbers representable as sums
of two squares. Using the checkerboard coloring, then an analogous statement
follows for the number of spanning trees in planar self-dual graphs.

</DOC>
<DOC>
<DOCNO> 71248 </DOCNO>
Review on B^0- \bar{\rm \bf{B^0}} mixing and b-lifetimes measurements at


  A review of the results on B^0- \bar {\rm B^0} mixing and b-lifetimes
obtained by CDF, LEP and SLD collaborations is presented with special emphasis
on B^0_s- \bar {{\rm B}^0_s} mixing.

</DOC>
<DOC>
<DOCNO> 68155 </DOCNO>
Physics Goals of the Next Century @ CERN


  After recalling briefly the main physics issues beyond the Standard Model,
the main physics objectives of experiments at CERN in the coming decade(s) are
reviewed. These include the conclusion of the LEP programme during the year
2000, a limited number of fixed-target experiments during the following years,
the CNGS long-baseline neutrino programme and the LHC, both scheduled to start
in 2005. Then possible accelerator projects at CERN after the LHC are reviewed,
in the expectation that an $e^+ e^-$ linear collider in the TeV energy range
will be built elsewhere. The default option for CERN's next major project may
be the CLIC multi-TeV $e^+ e^-$ collider project. Also interesting is the
option of a three-step scenario for muon storage rings, starting with a
neutrino factory, continuing with one or more Higgs factories, and culminating
in a $\mu^+ \mu^-$ collider at the high-energy frontier.

</DOC>
<DOC>
<DOCNO> 10719 </DOCNO>
Random background charges and Coulomb blockade in one-dimensional tunnel


  We have numerically studied the behavior of one dimensional tunnel junction
arrays when random background charges are included using the ``orthodox''
theory of single electron tunneling. Random background charge distributions are
verified in both amplitude and density. The use of a uniform array as a
transistor is discussed both with and without random background charges. An
analytic expression for the gain near zero gate voltage in a uniform array with
no background charges is derived. The gate modulation with background charges
present is simulated.

</DOC>
<DOC>
<DOCNO> 151023 </DOCNO>
On an effective action of monopoles in Abelian projections of Yang-Mills


  A path integral description of an effective action of monopoles in Abelian
projections of Yang-Mills theories is discussed and used to establish a
projection independence of the effective action. A dynamic regime in which the
effective dynamics may contain massive solitonic excitations is described.

</DOC>
<DOC>
<DOCNO> 150746 </DOCNO>
Understanding of the Renormalization Program in a mathematically


  we show there exists a mathematically consistent framework in which the
Renormalization Program can be understood in a natural manner. The framework
does not require any violations of mathematical rigor usually associated with
the Renormalization program. We use the framework of the non-local field
theories [these carry a finite mass scale (\Lambda)]and set up a finite
perturbative program. We show how this program leads to the perturbation series
of the usual renormalization program [except one difference] if the series is
restructured .We further show that the comparison becomes possible if there
exists a finite mass scale (\Lambda), with certain properties, in the Quantum
Field theory [which we take to be the scale present in the nonlocal theory]. We
give a way to estimate the scale (\Lambda). We also show that the finite
perturbation program differs from the usual renormalization program by a term;
which we propose can also be used to put a bound on (\Lambda).

</DOC>
<DOC>
<DOCNO> 69105 </DOCNO>
Light Fermion Finite Mass Effects in Non-relativistic Bound States


  We present analytic expressions for the vacuum polarization effects due to a
light fermion with finite mass in the binding energy and in the wave function
at the origin of QED and (weak coupling) QCD non-relativistic bound states.
Applications to exotic atoms, \Upsilon (1s) and t\bar{t} production near
threshold are briefly discussed.

</DOC>
<DOC>
<DOCNO> 8923 </DOCNO>
Kondo effect in multielectron quantum dots at high magnetic fields


  We present a general description of low temperature transport through a
quantum dot with any number of electrons at filling factor $1<\nu <2$. We
provide a general description of a novel Kondo effect which is turned on by
application of an appropriate magnetic field. The spin-flip scattering of
carriers by the quantum dot only involves two states of the scatterer which may
have a large spin. This process is described by spin-flip Hubbard operators,
which change the angular momentum, leading to a Kondo Hamiltonian. We obtain
antiferromagnetic exchange couplings depending on tunneling amplitudes and
correlation effects. Since Kondo temperature has an exponential dependence on
exchange couplings, quantitative variations of the parameters in different
regimes have important experimental consequences. In particular, we discuss the
{\it chess board} aspect of the experimental conductance when represented in a
grey scale as a function of both the magnetic field and the gate potential
affecting the quantum dot.

</DOC>
<DOC>
<DOCNO> 118192 </DOCNO>
Approximations of the self-similar solution for blastwave in a medium


  Approximations of the Sedov self-similar solution for a strong point
explosion in a medium with the power-law density distribution \rho^o\propto
r^{-m} are reviewed and their accuracy are analyzed. Taylor approximation is
extended to cases m\neq 0. Two approximations of the solution are presented in
the Lagrangian coordinates for spherical, cylindrical and plane geometry. These
approximations may be used for the investigation of the ionization structure of
the adiabatic flow, i.e., inside adiabatic supernova remnants.

</DOC>
<DOC>
<DOCNO> 100707 </DOCNO>
Gaussian limit for determinantal random point fields


  We prove that under fairly general conditions properly rescaled determinantal
random point field converges to a generalized Gaussian random process.

</DOC>
<DOC>
<DOCNO> 101112 </DOCNO>
Nonuniformly elliptic variational equations with gauge invariance


  A class of quasilinear systems for geometric objects is studied near a point
of elliptic degeneracy.

</DOC>
<DOC>
<DOCNO> 102183 </DOCNO>
A matrix model for quantum SL_2


  We describe a topological ribbon Hopf algebra whose elements are sequences of
matrices. The algebra is a quantum version of U(sl_2).

</DOC>
<DOC>
<DOCNO> 120171 </DOCNO>
Circular Polarization Induced by Scintillation in a Magnetized Medium


  A new theory is presented for the development of circular polarization as
radio waves propagate through the turbulent, birefringent interstellar medium.
The fourth order moments of the wavefield are calculated and it is shown that
unpolarized incident radiation develops a nonzero variance in circular
polarization. A magnetized turbulent medium causes the Stokes parameters to
scintillate in a non-identical manner. A specific model for this effect is
developed for the case of density fluctuations in a uniform magnetic field.

</DOC>
<DOC>
<DOCNO> 120781 </DOCNO>
Molecular Gas Concentrations Outside the Merging Disks


  We present our preliminary BIMA CO(1-0) images of II~Zw~96 which show huge
molecular gas concentrations outside the merging disks. The dominant extra-disk
CO concentrations in II~Zw~96 correspond to the two star-forming ``knots''
hidden by dust, whereas the others are associated with the two spiral disks.
The unique huge CO concentrations, $\approxgt 5$ kpc away from the merging
nuclei, account for $\approxgt 50 %$ of the total CO emission, yet only at a
moderate gas surface density as compared with that of ultraluminous infrared
galaxies (ULIGs). We tentatively conclude that the huge extra-disk gas
concentrations are most likely the overlap region of the gas disks, not
necessarily coinciding with the stellar disks overlap region. The gas disks
overlap region could be formed prior to the merging of the stellar disks and
become the overlap regions found between the disks like that in Arp~244 (the
``Antennae'' galaxies). These overlap regions would eventually nurture the {\it
extreme starbursts} and evolve into the extended gas disk surrounding the
double nuclei in final merging in most ULIGs.

</DOC>
<DOC>
<DOCNO> 11493 </DOCNO>
Superconductive properties of thin dirty SN bilayers


  The theory of superconductivity in thin SN sandwiches (bilayers) in the
diffusive limit is developed within the standard Usadel equation method, with
particular emphasis on the case of very thin superconductive layers, d_S <<
d_N. The proximity effect in the system is governed by the interlayer interface
resistance (per channel) \rho_{int}. The case of relatively low resistance
(which can still have large absolute values) can be completely studied
analytically. The theory describing the bilayer in this limit is of BCS type
but with the minigap (in the single-particle density of states) E_g << \Delta
substituting the order parameter \Delta in the standard BCS relations; the
original relations are thus severely violated. In the opposite limit of an
opaque interface, the behavior of the system is in many respects close to the
BCS predictions. Over the entire range of \rho_{int}, the properties of the
bilayer are found numerically. Finally, it is shown that the results obtained
for the bilayer also apply to more complicated structures such as SNS and NSN
trilayers, SNINS and NSISN systems, and SN superlattices.

</DOC>
<DOC>
<DOCNO> 170268 </DOCNO>
Interference of macroscopic superpositions


  We propose a simple experimental procedure based on the Elitzur-Vaidman
scheme to test the persistence of macroscopic superpositions. We conjecture
that its implementation will reveal the persistence of superpositions of
macroscopic objects in the absence of a direct act of observation.

</DOC>
<DOC>
<DOCNO> 118779 </DOCNO>
Possible evidence of quark matter in neutron star X-ray binaries


  We study the spin evolution of X-ray neutron stars in binary systems, which
are being spun up by mass transfer from accretion disks. Our investigation
reveals that a quark phase transition resulting from the changing central
density induced by the changing spin, can lead to a pronounced peak in the
frequency distribution of X-ray neutron stars. This finding provides one of
several possible explanations available in the literature, or at least a
contributor to part of the observed anomalous frequency distribution of neutron
stars in low-mass X-ray binaries (LMXBs), which lie in a narrow band centered
at about 300 Hz, as found by the Rossi Explorer (RXTE).

</DOC>
<DOC>
<DOCNO> 14014 </DOCNO>
Measurement of one-particle correlations and momentum distributions for


  van Hove's theory of scattering of probe particles by a macroscopic target is
generalized so as to relate the differential cross section for atomic ejection
via stimulated Raman transitions to one-particle momentum-time correlations and
momentum distributions of 1D trapped gases. This method is well suited to
probing the longitudinal momentum distributions of 1D gases in situ, and
examples are given for bosonic and fermionic atoms.

</DOC>
<DOC>
<DOCNO> 13711 </DOCNO>
Effect of controlled disorder on quasiparticle thermal transport in


  Low temperature thermal conductivity, $\kappa$, of optimally-doped Bi2212 was
studied before and after the introduction of point defects by electron
irradiation. The amplitude of the linear component of $\kappa$ remains
unchanged, confirming the universal nature of heat transport by zero-energy
quasiparticles. The induced decrease in the absolute value of $\kappa$ at
finite temperatures allows us to resolve a nonuniversal term in $\kappa$ due to
conduction by finite-energy quasiparticles. The magnitude of this term provides
an estimate of the quasiparticle lifetime at subkelvin temperatures.

</DOC>
<DOC>
<DOCNO> 83172 </DOCNO>
About the finding of independent vertices of a graph


  We examine the Maximum Independent Set Problem in an undirected graph. The
main result is that this problem can be considered as the solving the same
problem in a subclass of the weighted normal twin-orthogonal graphs. The
problem is formulated which is dual to the problem above. It is shown that, for
trivial twin-orthogonal graphs, any of its maximal independent set is also
maximum one.

</DOC>
<DOC>
<DOCNO> 12781 </DOCNO>
Path integral Monte Carlo simulations of silicates


  We investigate the thermal expansion of crystalline SiO$_2$ in the $\beta$--
cristobalite and the $\beta$-quartz structure with path integral Monte Carlo
(PIMC) techniques. This simulation method allows to treat low-temperature
quantum effects properly. At temperatures below the Debye temperature, thermal
properties obtained with PIMC agree better with experimental results than those
obtained with classical Monte Carlo methods.

</DOC>
<DOC>
<DOCNO> 71403 </DOCNO>
".. I didn't reflect much on what I was doing.." How Planck discovered


  On December 14. 1900, Max Planck communicated his derivation of his radiation
formula, which he later called ``an act of desperation''. This date is widely
recognized as birthday of quantum theory. For Planck it meant the end of his
carefully planned and ambitious research project, in which he wanted to
establish the second law of thermodynamics as strictly deterministic law for
systems of matter and electromagnetic radiation in interaction. He knew he
could not succeed within classical mechanics, but had the somewhat strange hope
that the inclusion of Maxwell's electrodynamics would change the situation.
Later he always disagreed with Einstein's light-quantum hypothesis, because it
implied a renunciation from Maxwell's theory, which in Germany gained full
recognition and acceptance as late as the 1890's, mainly through the
theoretical and experimental work of Heinrich Hertz.

</DOC>
<DOC>
<DOCNO> 71422 </DOCNO>
Weak Decays of Heavy Quarks


  We review some aspects of weak decays of hadrons containing one heavy quark.
The main emphasis is on $B$ physics, in particular in the framework of the
Heavy Quark Effective Theory.

</DOC>
<DOC>
<DOCNO> 70117 </DOCNO>
Evolution of DIS structure functions at small x


  A short review of recent theoretical results on the Deep Inelastic Scattering
is presented.

</DOC>
<DOC>
<DOCNO> 71885 </DOCNO>
Neutrino-Induced Giant Air Showers in Large Extra Dimension Models


  In models based on large extra dimensions where massive spin 2 exchange can
dominate at high energies, the neutrino-proton cross section can rise to
typical hadronic values at energies above 10^20 eV. The neutrino then becomes a
candidate for the primary that initiates the highest energy cosmic ray showers.
We investigate characteristics of neutrino-induced showers compared to
proton-induced showers. The comparison includes study of starting depth,
profile with depth, lateral particle distribution at ground and muon lateral
distribution at ground level. We find that for cross sections above 20 mb there
are regions of parameter space where the two types of showers are essentially
indistinguishable. We conclude that the neutrino candidate hypothesis cannot be
ruled out on the basis of shower characteristics.

</DOC>
<DOC>
<DOCNO> 9589 </DOCNO>
Phase transitions in social impact models of opinion formation


  We study phase transitions in models of opinion formation which are based on
the social impact theory. Two different models are discussed: (i) a
cellular--automata based model of a finite group with a strong leader where
persons can change their opinions but not their spatial positions, and (ii) a
model with persons treated as active Brownian particles interacting via a
communication field. In the first model, two stable phases are possible: a
cluster around the leader, and a state of social unification. The transition
into the second state occurs for a large leader strength and/or for a high
level of social noise. In the second model, we find three stable phases, which
correspond either to a ``paramagnetic'' phase (for high noise and strong
diffusion), a ``ferromagnetic'' phase (for small nose and weak diffusion), or a
phase with spatially separated ``domains'' (for intermediate conditions).

</DOC>
<DOC>
<DOCNO> 100181 </DOCNO>
The quantum supergroup SPO_q(2n|2m) and an SPO_q(2n|2m)-covariant


  Recently, the R-matrix of the symplecto-orthogonal quantum superalgebra
U_q(spo(2n|2m)) in the vector representation has been calculated. In the
present work, this R-matrix is used to introduce the corresponding quantum
supergroup SPO_q(2n|2m) and to construct an SPO_q(2n|2m)-covariant quantum Weyl
superalgebra.

</DOC>
<DOC>
<DOCNO> 116862 </DOCNO>
Pulsed Neutron Source using 100-MeV electron Linac at Pohang Accelerator


  The Pohang Accelerator Laboratory operates an electron linac for the pulsed
neutron source as one of the long-term nuclear R&D programs at the Korea Atomic
Energy Research Institute. The designed beam parameters are as follows; The
nominal beam energy is 100 MeV, the maximum beam power is 10 kW, and the beam
current is varied from 300 mA to 5A depends on the pulse repetition. The linac
has two operating modes: one for short pulse modes with the various repetitions
between 2 ns and 100 ns and the other for long pulse modes with 1 ms
repetition. We have constructed and tested an electron linac based on the
existing equipment such as a SLAC-5045 klystron, two constant gradient
accelerating sections, and a thermionic RF-gun. We present the characteristics
of the linac and report the status of the pulsed neutron source facilities
include a target system and time-of-flight paths.

</DOC>
<DOC>
<DOCNO> 71008 </DOCNO>
Tools for RHIC: Review of Models


  We discuss the present status of microscopic models for RHIC, with an
emphasis on models being realized via the Monte Carlo technique. This review is
to a large extent based on the OSCAR3 workshop, where general concepts and new
trends in this field have been discussed.

</DOC>
<DOC>
<DOCNO> 10009 </DOCNO>
Effects of Fermi energy, dot size and leads width on weak localization


  Magnetotransport in chaotic quantum dots at low magnetic fields is
investigated by means of a tight binding Hamiltonian on L x L clusters of the
square lattice. Chaoticity is induced by introducing L bulk vacancies. The
dependence of weak localization on the Fermi energy, dot size and leads width
is investigated in detail and the results compared with those of previous
analyses, in particular with random matrix theory predictions. Our results
indicate that the dependence of the critical flux Phi_c on the square root of
the number of open modes, as predicted by random matrix theory, is obscured by
the strong energy dependence of the proportionality constant. Instead, the size
dependence of the critical flux predicted by Efetov and random matrix theory,
namely, Phi_c ~ sqrt{1/L}, is clearly illustrated by the present results. Our
numerical results do also show that the weak localization term significantly
decreases as the leads width W approaches L. However, calculations for W=L
indicate that the weak localization effect does not disappear as L increases.

</DOC>
<DOC>
<DOCNO> 178522 </DOCNO>
A two-pion exchange three-nucleon force based on a realistic pi-N


  The contribution of a $\pi \pi$-exchange three-body force to the
three-nucleon binding energy is calculated in terms of a $\pi N$ amplitude. The
latter is based on a meson-theoretical model of $\pi N$ interaction developed
by the J\"ulich group. Similar to a previous study based on simple
phenomenological $\pi N$ potentials a very small effect of the resulting
three-body force is found. Possible origins of the two-orders-of-magnitude
descrepancy between the present result and the values obtained for the
Tucson-Melbourne three-body force are investigated. Evidence is provided that
this discrepancy is most likely due to strikingly different off-shell
properties of the $\pi N$ amplitudes underlying the two approaches.

</DOC>
<DOC>
<DOCNO> 117359 </DOCNO>
First Light Measurements of Capella with the Low Energy Transmission


  We present the first X-ray spectrum obtained by the Low Energy Transmission
Grating Spectrometer (LETGS) aboard the Chandra X-ray Observatory. The spectrum
is of Capella and covers a wavelength range of 5-175 A (2.5-0.07 keV). The
measured wavelength resolution, which is in good agreement with ground
calibration, is $\Delta \lambda \simeq$ 0.06 A (FWHM). Although in-flight
calibration of the LETGS is in progress, the high spectral resolution and
unique wavelength coverage of the LETGS are well demonstrated by the results
from Capella, a coronal source rich in spectral emission lines. While the
primary purpose of this letter is to demonstrate the spectroscopic potential of
the LETGS, we also briefly present some preliminary astrophysical results. We
discuss plasma parameters derived from line ratios in narrow spectral bands,
such as the electron density diagnostics of the He-like triplets of carbon,
nitrogen, and oxygen, as well as resonance scattering of the strong Fe XVII
line at 15.014 A.

</DOC>
<DOC>
<DOCNO> 151069 </DOCNO>
Hagedorn Behaviour of Little String Theory from String Corrections to


  Following the conjectured duality between near-horizon NS5-branes and little
string theory, the string-corrected thermodynamics of near-horizon NS5-branes
is studied and found to agree with the statistical thermodynamics of a 5+1
dimensional supersymmetric string theory near the Hagedorn temperature.
Specifically, tree-level corrections to the temperature are argued to vanish,
in accordance with the duality, while the one-loop string correction to the
NS5-brane thermodynamics is shown to generate the correct temperature
dependence of the entropy.

</DOC>
<DOC>
<DOCNO> 69179 </DOCNO>
Oscillating Color Transparency in $\pi A\to \pi p (A-1)$ and $\gamma


  The energy dependence of $90^o$ $cm$ fixed angle scattering of $\pi p \to
\pi' p'$ and $\gamma p\to \pi^+ n$ at large momentum transfer are found to be
well described in terms of interfering short and long distance amplitudes with
dynamical phases induced by Sudakov effects. We calculate the color
transparency ratio for the corresponding processes in nuclear environments $\pi
A\to \pi'p(A-1)$ and $\gamma A\to \pi N (A-1)$ taking nuclear filtering into
account. A prediction that the transparency ratio for these reactions will
oscillate with energy provides an important test of the Sudakov phase shift and
nuclear filtering hypothesis which is testable in upcoming experiments.

</DOC>
<DOC>
<DOCNO> 68229 </DOCNO>
Deeply virtual Compton scattering at small x


  We calculate the cross section of the deeply virtual Compton scattering at
large energies and intermediate momentum transfers.

</DOC>
<DOC>
<DOCNO> 12833 </DOCNO>
Topology of event distribution as a generalized definition of phase


  We propose a definition of phase transitions in finite systems based on
topology anomalies of the event distribution in the space of observations. This
generalizes all the definitions based on the curvature anomalies of
thermodynamical potentials and provides a natural definition of order
parameters. The proposed definition is directly operational from the
experimental point of view. It allows to study phase transitions in Gibbs
equilibria as well as in other ensembles such as the Tsallis ensemble.

</DOC>
<DOC>
<DOCNO> 10076 </DOCNO>
Charge, Orbital and Magnetic Order in Nd0.5Ca0.5MnO3


  In the manganite Nd0.5Ca0.5MnO3, charge ordering occurs at much higher
temperature than the antiferromagnetic order (TCO=250K,TN=160K).
 The magnetic behavior of the phase TN<T<TCO is puzzling: its magnetization and
susceptibility are typical of an antiferromagnet while no magnetic order is
detected by neutron diffraction.We have undertaken an extensive study of the
cristallographic, electric and magnetic properties of Nd0.5Ca0.5MnO3 and
established its phase diagram as a function of temperature and magnetic field.
The charge disordered, paramagnetic phase above TCO present ferromagnetic
correlations. An antiferromagnetic CE phase prevails below TN, with complete
charge and orbital ordering. In the intermediate temperature range, charge
ordering occurs while orbital ordering sets in progressively, with no magnetic
order. Strong magnetic fields destroy the charge ordered phases in a fisrt
order transition towards a ferromagnetic state.

</DOC>
<DOC>
<DOCNO> 123206 </DOCNO>
Post-Starburst Populations Near and Far - The Potential of Near-IR


  The efficient use of near-IR data in studies of external stellar populations
depends on our ability to recognize the nature of the predominant sources of
light, and to interprete these findings in terms of age and metallicity. Here
we focus on elderly post-starburst populations, with ages of 0.1-1 Gyr. New
models confirm that they are indeed expected to display specific spectral
signatures in the near-IR, due to variable M stars of the asymptotic giant
branch and to carbon stars. The signatures depend on age and metallicity. We
summarize the status of current quantitative predictions and emphasize the
importance of an empirical calibration of the spectral synthesis models.

</DOC>
<DOC>
<DOCNO> 150599 </DOCNO>
Curvature Singularities: the Good, the Bad, and the Naked


  Necessary conditions are proposed for the admissibility of singular classical
solutions with 3+1-dimensional Poincare invariance to five-dimensional gravity
coupled to scalars. Finite temperature considerations and examples from AdS/CFT
support the conjecture that the scalar potential must remain bounded above for
a solution to be physical. Having imposed some restrictions on naked
singularities allows us to comment on a recent proposal for solving the
cosmological constant problem.

</DOC>
<DOC>
<DOCNO> 68179 </DOCNO>
Measurement of entropy of a multiparticle system: a do-list


  An algorithm for measurement of entropy in multiparticle systems, based on
recently published proposal of the present authors, is given. Dependence on
discretization of the system and effects of multiparticle correlations are
discussed in some detail.

</DOC>
<DOC>
<DOCNO> 121363 </DOCNO>
ROSAT HRI catalogue of X-ray sources in the SMC region


  During the operational phase of the ROSAT satellite between 1990 and 1998 the
X-ray telescope pointed 71 times to the Small Magellanic Cloud (SMC) for
observations with the High Resolution Imager (HRI), covering a field of 5 deg x
5 deg. From this data a catalogue of 121 discrete X-ray sources was derived. By
cross-correlating the source catalogue with the SIMBAD data base and the TYCHO
catalogue, the systematic positional error of the HRI source positions could be
reduced. In total the X-ray position for 99 HRI sources was corrected yielding
positional errors between 1 arcsec and 16 arcsec. The HRI catalogue was also
cross-correlated with the catalogues derived from the ROSAT Position Sensitive
Propotional Counter (PSPC) pointings (Kahabka et al. 1999, Haberl et al. 2000).
For 75 HRI sources PSPC counterparts were found and thus hardness ratios are
given. With the help of the information obtained from the cross-correlations 56
HRI sources were identified with objects of known or proposed nature. Four
foreground stars, six supernova remnants, four supersoft sources, 12 X-ray
binaries, and one AGN were detected by the HRI. Based on the existence of a
likely optical counterpart or properties like hardness ratio and X-ray to
optical flux ratio, further 15 HRI sources were classified into different
source types.

</DOC>
<DOC>
<DOCNO> 174562 </DOCNO>
Production of hot nuclei in Fermi energy domain: from peripheral to


  The production mechanism of highly excited nuclei in the Fermi energy domain
is investigated. A phenomenological approach, based on the exciton model, is
used for the description of pre-equilibrium emission. A model of deep inelastic
transfer is employed for the peripheral collisions in the post-pre-equilibrium
stage. An approach to describe more central collisions is proposed. A geometric
overlap formula is employed in a way suitable for given energy domain. A simple
geometric approach describing the interaction of participant and spectator
zones is used to determine the incomplete fusion channel. Excitation energies
of both fragments are determined. Results of the calculation are compared to
available experimental data and an overall satisfactorily agreement is
obtained. The model's ability to describe the production of the hot nuclei can
be employed in the study of multifragmentation and/or in the production of rare
beams.

</DOC>
<DOC>
<DOCNO> 72081 </DOCNO>
Counting Form Factors of Twist-Two Operators


  We present a simple method to count the number of hadronic form factors based
on the partial wave formalism and crossing symmetry. In particular, we show
that the number of independent nucleon form factors of spin-n, twist-2
operators (the vector current and energy-momentum tensor being special
examples) is n+1. These generalized form factors define the generalized
(off-forward) parton distributions that have been studied extensively in the
recent literature. In proving this result, we also show how the J^{PC} rules
for onium states arise in the helicity formalism.

</DOC>
<DOC>
<DOCNO> 178694 </DOCNO>
Inclusive quasielastic electron scattering on $^6$He: a probe of the


  We investigate inclusive electron scattering reactions on two-neutron halo
nuclei in the quasielastic region. Expressions for the cross section and
structure functions are given assuming that the halo nucleus can be described
as a three-body system (${core}+n+n$). The method is applied to $^6$He. We
compute cross sections and structure functions, and investigate the kinematic
conditions for which the observables are determined either by $\alpha$-knockout
or by halo neutron-knockout. The optimal kinematical domain to disantangle the
momentum distributions of the various components of the three--body system ($q
\lesssim 200$ MeV/c and $\omega < q^2/2M_N + 20$ MeV) are explored.

</DOC>
<DOC>
<DOCNO> 101139 </DOCNO>
Three alternating sign matrix identities in search of bijective proofs


  This paper highlights three known identities, each of which involves sums
over alternating sign matrices. While proofs of all three are known, the only
known derivations are as corollaries of difficult results. The simplicity and
natural combinatorial interpretation of these identities, however, suggest that
there should be direct, bijective proofs.

</DOC>
<DOC>
<DOCNO> 122146 </DOCNO>
Charting the temperature of the Hot Neutron Star in a Soft X-ray


  We explore the thermal evolution of a neutron star undergoing episodes of
intense accretion, separated by long periods of quiescence. By using an exact
cooling code we follow in detail the flow of heat in the star due to the
time-dependent accretion-induced heating from pycno-nuclear reactions in the
stellar crust, to the surface photon emission, and the neutrino cooling. These
models allow us to study the neutron stars of the Soft X-Ray Transients. In
agreement with Brown, Bildsten and Rutledge (1998) we conclude that the soft
component of the quiescent luminosity of Aql X-1, 4U 1608-522, and of the
recently discovered SAX J1808.4, can be understood as thermal emission from a
cooling neutron star with negligible neutrino emission. However, we show that
in the case of Cen X-4, despite its long recurrence time, strong neutrino
emission from the neutron star inner core is necessary to understand the
observed low ratio of quiescent to outburst luminosity. This result implies
that the neutron star in Cen X-4 is heavier than the one in the other systems
and the pairing critical temperature in its center must be low enough (well
below 10^9 K) to avoid a strong suppression of the neutrino emission.

</DOC>
<DOC>
<DOCNO> 69153 </DOCNO>
Effects of neutrino mixing on high-energy cosmic neutrino flux


  Several cosmologically distant astrophysical sources may produce high-energy
cosmic neutrinos (E \geq 10^6 GeV) of all flavors above the atmospheric
neutrino background. We study the effects of vacuum neutrino mixing in three
flavor framework on this cosmic neutrino flux. We also consider the effects of
possible mixing between the three active neutrinos and the (fourth) sterile
neutrino with or without Big-Bang nucleosynthesis constraints and estimate the
resulting final high-energy cosmic neutrino flux ratios on earth compatible
with currently existing different neutrino oscillation hints in a model
independent way. Further, we discuss the case where the intrinsic cosmic
neutrino flux does not have the standard ratio.

</DOC>
<DOC>
<DOCNO> 151522 </DOCNO>
q-Deformed Conformal Quantum Mechanics


  We construct a q-deformed version of the conformal quantum mechanics model of
de Alfaro, Fubini and Furlan for which the deformation parameter is complex and
the unitary time evolution of the system is preserved. We also study
differential calculus on the q-deformed quantum phase space associated with
such system.

</DOC>
<DOC>
<DOCNO> 121308 </DOCNO>
The Demise of the Classical BLR in the Luminous Quasar PG1416-129


  New observations of the broad-line quasar PG1416-129 reveal a large decline
in its continuum luminosity over the past ten years. In response to the
continuum change the ``classical'' broad component of Hbeta has almost
completely disappeared (a x10 decrease in flux). In its place there remains a
redshifted/redward asymmetric very broad emission line component. The
significance of this change is multifold: (1) It confirms the existence of a
distinct redshifted Very Broad Line Region (VBLR) component that persists after
the demise of the broad component and that is frequently observed, along with
the broad component, in radio-loud sources. (2) The smaller (x2) intensity
change in the Hbeta very broad component supports the previously advanced idea
that the VBLR is physically distinct and likely to arise in an optically thin
region close to the central source. (3) The presence of a strong very broad
component in the radio-quiet quasar PG1416-129 reinforces the notion that such
``population B'' quasars share similar spectroscopic (and hence geometrical and
kinematical) properties to radio-loud sources. (4) AGN can show broad, very
broad, or both line components simultaneously, making statistical comparisons
of source profile widths difficult. (5) The interpretation, in reverberation
studies, of the presence or lack of correlated response in broad line wings
will be affected by this composite BLR/VBLR structure.

</DOC>
<DOC>
<DOCNO> 8956 </DOCNO>
Binary hard-sphere fluids near a hard wall


  By using the Rosenfeld density functional we determine the number density
profiles of both components of binary hard-sphere fluids close to a planar hard
wall as well as the corresponding excess coverage and surface tension. The
comparison with published simulation data demonstrates that the Rosenfeld
functional, both its original version and sophistications thereof, is superior
to previous approaches and exhibits the same excellent accuracy as known from
studies of the corresponding one-component system.

</DOC>
<DOC>
<DOCNO> 10398 </DOCNO>
The preservation of the individuality of 3d atoms in a solid


  On basis of analysis of experimental results for more than 200 compounds with
3d and 4f elements we conjecture that atoms with unfilled 3d and 4f shells
preserve much of their atomic properties, manifested by the discrete electronic
structure, even then when they become the part of a solid. As a consequence,
electronic and magnetic properties of the 3d-ion containing compounds are
strongly affected by the existence of the atomic-like crystal-field fine
electronic structure.

</DOC>
<DOC>
<DOCNO> 150787 </DOCNO>
On the Supersymmetry and Gauge Structure of Matrix Theory


  Supersymmetric Ward identity for the low energy effective action in the
standard background gauge is derived for {\it arbitrary} trajectories of
supergravitons in Matrix Theory. In our formalism, the quantum-corrected
supersymmetry transformation laws of the supergravitons are directly identified
in closed form, which exhibit an intricate interplay between supersymmetry and
gauge (BRST) symmetry. As an application, we explicitly compute the
transformation laws for the source-probe configuration at 1-loop and confirm
that supersymmetry fixes the form of the action completely, including the
normalization, to the lowest order in the derivative expansion.

</DOC>
<DOC>
<DOCNO> 39622 </DOCNO>
Coherent e^+e^- pair creation at high energy muon colliders


  It is shown that at muon colliders with the energy in the region of 100 TeV
the process of coherent pair creation by the muon in the field of the opposing
beam becomes important and imposes some limitations on collider parameters.

</DOC>
<DOC>
<DOCNO> 151391 </DOCNO>
Casimir Energy in Non-Covariant Gauges


  The zero-point energy of a conducting spherical shell is studied by imposing
the axial gauge via path-integral methods, with boundary conditions on the
electromagnetic potential and ghost fields. The coupled modes are then found to
be the temporal and longitudinal modes for the Maxwell field. The resulting
system can be decoupled by studying a fourth-order differential equation with
boundary conditions on longitudinal modes and their second derivatives.
Complete agreement is found with a previous path-integral analysis in the
Lorenz gauge, and with Boyer's value. This investigation leads to a better
understanding of how gauge independence is achieved in quantum field theory on
backgrounds with boundary.

</DOC>
<DOC>
<DOCNO> 14080 </DOCNO>
Approximate formula for the ground state energy of anyons in 2D


  We determine approximate formula for the ground state energy of anyons in 2D
parabolic well which is valid for the arbitrary anyonic factor \nu and number
of particles N in the system. We assume that centre of mass motion energy is
not excluded from the energy of the system. Formula for ground state energy
calculated by variational principle contains logarithmic divergence at small
distances between two anyons which is regularized by cut-off parameter. By
equating this variational formula to the analogous formula of Wu near bosonic
limit (\nu ~ 0)we determine the value of the cut-off and thus derive the
approximate formula for the ground state energy for the any \nu and N. We
checked this formula at \nu=1, when anyons become fermions, for the systems
containing two to thirty particles. We find that our approximate formula has an
accuracy within 6%. It turns out, at the big number N limit the ground state
energy has square root dependence on factor \nu.

</DOC>
<DOC>
<DOCNO> 170193 </DOCNO>
Experimental Realization of an Order-Finding Algorithm with an NMR


  We report the realization of a nuclear magnetic resonance (NMR) quantum
computer which combines the quantum Fourier transform (QFT) with exponentiated
permutations, demonstrating a quantum algorithm for order-finding. This
algorithm has the same structure as Shor's algorithm and its speed-up over
classical algorithms scales exponentially. The implementation uses a
particularly well-suited five quantum bit molecule and was made possible by a
new state initialization procedure and several quantum control techniques.

</DOC>
<DOC>
<DOCNO> 178849 </DOCNO>
Inclusive Particle Spectra at RHIC


  A simulation is performed of the recently reported data from PHOBOS at
energies of 56 and 130 A GeV using the relativistic heavy ion cascade LUCIFER
which had previously given a good description of the NA49 inclusive spectra at
E=17.2 A GeV. The results compare well with these early measurements at RHIC.

</DOC>
<DOC>
<DOCNO> 13617 </DOCNO>
Staggered liquid phases of the 1D Kondo-Heisenberg lattice model


  We introduce a new family of one dimensional liquids, which we label as
''Staggered-Liquids'', in the phase diagram of the 1D Kondo-Heisenberg model.
It encompasses three distinct spin gapped liquids and a new Luttinger liquid
phase. A Staggered Liquid is characterized by gapless modes with ''large
fermi-sea'' signature in the charge density wave (CDW) mode, and in that the
superconducting order involves the near condensation of charge-2e Cooper pairs
with finite center of mass momentum. In particular, the conventional gapless
$2k_{F}$ CDW and $k=0$ pairing modes are absent. In the process, we
analytically derive the phase transition from an intermediate coupling spin gap
phase to the strong coupling gapless LL phase of the Kondo-Heisenberg lattice
model.

</DOC>
<DOC>
<DOCNO> 174560 </DOCNO>
Robust Nuclear Observables and Constraints on Random Interactions


  The predictions of the IBM two-body random ensemble are compared to empirical
results on nuclei from Z=8 to 100. Heretofore unrecognized but robust empirical
trends are identified and related both to the distribution of valence nucleon
numbers and to the need for and applicability of specific, non-random
interactions. Applications to expected trends in exotic nuclei are discussed.

</DOC>
<DOC>
<DOCNO> 69033 </DOCNO>
On The Origin of the OZI Rule in QCD


  The OZI rule is prominent in hadronic phenomena only because OZI violation is
typically an order of magnitude smaller than expected from large N_c arguments.
With its standard ^3P_0 pair creation operator for hadronic decays by flux tube
breaking, the quark model respects the OZI rule at tree level and exhibits the
cancellations between OZI-violating meson loop diagrams required for this
dramatic suppression. However, if the quark model explanation for these
cancellations is correct, then OZI violation would be expected to be large in
the nonet with the same quantum numbers as the pair creation operator: the
0^{++} mesons. Experiment is currently unable to identify these mesons, but we
report here on a lattice QCD calculation which confirms that the OZI rule
arises from QCD in the vector and axial vector mesons as observed, and finds a
large violation of the rule in the scalar mesons as anticipated by the quark
model. In view of this result, we make some remarks on possible connections
between the ^3P_0 pair creation model, scalar mesons, and the U_A(1) anomaly
responsible for the large OZI violation which drives the \eta' mass. In
particular, we note that our result favors the large N_c and not the instanton
interpretation of the solution to the \eta' mass problem.

</DOC>
<DOC>
<DOCNO> 118904 </DOCNO>
Tidal spin-up of stars in dense stellar cusps around massive black holes


  We show that main-sequence stars in dense stellar cusps around massive black
holes are likely to rotate at a significant fraction of the centrifugal breakup
velocity due to spin-up by hyperbolic tidal encounters. We use realistic
stellar structure models to calculate analytically the tidal spin-up in soft
encounters, and extrapolate these results to close and penetrating collisions
using smoothed particle hydrodynamics simulations. We find that the spin-up
falls off only slowly with distance from the black hole because the increased
tidal coupling in slower collisions at larger distances compensates for the
decrease in the stellar density. We apply our results to the stars near the
massive black hole in the Galactic Center. Over their lifetime, ~1 Msol main
sequence stars in the inner 0.3 pc of the Galactic Center are spun-up on
average to ~10%--30% of the centrifugal breakup limit. Such rotation is ~20--60
times higher than is usual for such stars and may affect their subsequent
evolution and their observed properties.

</DOC>
<DOC>
<DOCNO> 178924 </DOCNO>
Nuclear Physics Neutrino PreTown Meeting: Summary and Recommendations


  In preparation for the nuclear physics Long Range Plan exercise, a group of
104 neutrino physicists met in Seattle September 21-23 to discuss both the
present state of the field and the new opportunities of the next decade. This
report summarizes the conclusions of that meeting and presents its
recommendations. Further information is available at the workshop's web site.
This report will be further reviewed at the upcoming Oakland Town Meeting.

</DOC>
<DOC>
<DOCNO> 102859 </DOCNO>
Convergence of formal equivalences of hypersurfaces


  A formal invertible equivalence between two minimal real analytic
hypersurfaces converges if and only if the hypersurfaces are holomorphically
nondegenerate

</DOC>
<DOC>
<DOCNO> 81011 </DOCNO>
Colour Confinement in the Lattice Landau Gauge QCD Simulation


  The colour confinement criterion proposed by Kugo and Ojima is tested in the
lattice Landau gauge QCD simulation. The renormalization effects are studied by
measuring the gluon propagator, ghost propagator, three gluon vertex and the
ghost-antighost-gluon vertex.

</DOC>
<DOC>
<DOCNO> 120858 </DOCNO>
The Current Status of CLASS


  I give a brief overview of the current status of some aspects of the Cosmic
Lens All-Sky Survey (CLASS): description of the survey, current list of lens
systems, cosmological parameters from lensing statistics, H_0 from time delays,
dark lenses, wide-separation lenses.

</DOC>
<DOC>
<DOCNO> 117696 </DOCNO>
Tests of the Accelerating Universe with Near-Infrared Observations of a


  We have measured the rest-frame B,V, and I-band light curves of a
high-redshift type Ia supernova (SN Ia), SN 1999Q (z=0.46), using HST and
ground-based near-infrared detectors.
  A goal of this study is the measurement of the color excess, E_{B-I}, which
is a sensitive indicator of interstellar or intergalactic dust which could
affect recent cosmological measurements from high-redshift SNe Ia. Our
observations disfavor a 30% opacity of SN Ia visual light by dust as an
alternative to an accelerating Universe. This statement applies to both
Galactic-type dust
 (rejected at the 3.4 sigma confidence level) and greyer dust (grain size > 0.1
microns; rejected at the 2.3 to 2.6 sigma confidence level) as proposed by
Aguirre (1999). The rest-frame $I$-band light cur ve shows the secondary
maximum a month after B maximum typical of nearby SNe Ia of normal luminosi ty,
providing no indication of evolution as a function of redshift out to z~0.5. A
n expanded set of similar observations could improve the constraints on any
contribution of extragalactic dust to the dimming of high-redshift SNe Ia.

</DOC>
<DOC>
<DOCNO> 10089 </DOCNO>
Spontaneous symmetry breaking in the colored Hubbard model


  The Hubbard model is reformulated in terms of different ``colored'' fermion
species for the electrons or holes at different lattice sites.
Antiferromagnetic ordering or d-wave superconductivity can then be described in
terms of translationally invariant expectation values for colored composite
scalar fields. A suitable mean field approximation for the two dimensional
colored Hubbard model shows indeed phases with antiferromagnetic ordering or
d-wave superconductivity at low temperature. At low enough temperature the
transition to the antiferromagnetic phase is of first order. The present
formulation also allows an easy extension to more complicated microscopic
interactions.

</DOC>
<DOC>
<DOCNO> 13955 </DOCNO>
Spatiotemporal Stochastic Resonance in Fully Frustrated Josephson


  We consider a Josephson-junction ladder in an external magnetic field with
half flux quantum per plaquette. When driven by external currents, periodic in
time and staggered in space, such a fully frustrated system is found to display
spatiotemporal stochastic resonance under the influence of thermal noise. Such
resonance behavior is investigated both numerically and analytically, which
reveals significant effects of anisotropy and yields rich physics.

</DOC>
<DOC>
<DOCNO> 120410 </DOCNO>
On the Energy Equation and Efficiency Parameter of the Common Envelope


  We have investigated the structure of evolved giant stars with masses 3-10
M_sun in order to evaluate the binding energy of the envelope to the core prior
to mass transfer in close binary systems. This binding energy is expressed by a
parameter lambda which is crucial for determining the outcome of binaries
evolving through a common envelope (CE) and spiral-in phase. We discuss the
lambda-parameter and the efficiency of envelope ejection in the CE-phase, and
show that lambda depends strongly on the evolutionary stage (i.e. stellar
radius) of the donor star at the onset of the mass transfer. The existence of
this relation enables us to introduce a new approach for solving the energy
equation. For a given observed binary system we can derive a unique solution
for the original mass and age of the donor star, as well as the pre-CE orbital
period. We find that the value of lambda is typically between 0.2 and 0.8. But
in some cases, particularly on the asymptotic giant branch of lower-mass stars,
it is possible that lambda > 5. A high value of lambda (rather than assuming a
high efficiency parameter, eta_CE >1) is sufficient to explain the long final
orbital periods observed among those binary millisecond pulsars which are
believed to have evolved through a CE-phase. We also present a tabulation of
lambda as a function of stellar radius and mass, which is useful for a quick
estimation of the orbital decay during a common envelope and spiral-in phase.

</DOC>
<DOC>
<DOCNO> 8678 </DOCNO>
Thermodynamic Fingerprints of Disorder in Flux Line Lattices and other


  We examine probability distributions for thermodynamic quantities in
finite-sized random systems close to criticality. Guided by available exact
results, a general ansatz is proposed for replicated free energies, which leads
to scaling forms for cumulants of various macroscopic observables. For the
specific example of a planar flux line lattice in a two dimensional
superconducting film near H_c1, we provide detailed results for the statistics
of the magnetic flux density, susceptibility, heat capacity, and their
cross-correlations.

</DOC>
<DOC>
<DOCNO> 118618 </DOCNO>
A generalized inflation model with cosmic gravitational waves


  We propose a $\Lambda$-inflation model which explains a large fraction of the
COBE signal by cosmic gravitational waves. The primordial density perturbations
fulfil both the contraints of large-scale microwave background and galaxy
cluster normalization. The model is tested against the galaxy cluster power
spectrum and the high-multipole angular CMB anisotropy.

</DOC>
<DOC>
<DOCNO> 118646 </DOCNO>
Infrared Classification of Galactic Objects


  Unbiased analysis shows that IRAS data reliably differentiate between the
early and late stages of stellar evolution because objects at these stages
clearly segregate in infrared color-color diagrams. Structure in these diagrams
is primarily controlled by the density distribution of circumstellar dust. The
density profile around older objects is the steepest, declining as $r^{-2}$,
while young objects have profiles that vary as $r^{-3/2}$ and flatter. The
different density profiles reflect the different dynamics that govern the
different environments. Our analysis also shows that high mass star formation
is strongly concentrated within \about 5 kpc around the Galactic center, in
support of other studies.

</DOC>
<DOC>
<DOCNO> 40516 </DOCNO>
Inclusive Jet Production in pbar p Collisions


  We report a new measurement of the pseudorapidity (eta) and transverse-energy
(Et) dependence of the inclusive jet production cross section in pbar b
collisions at sqrt(s) = 1.8 TeV using 95 pb**-1 of data collected with the
DZero detector at the Fermilab Tevatron. The differential cross section
d^2sigma/dEt deta is presented up to |eta| = 3, significantly extending
previous measurements. The results are in good overall agreement with
next-to-leading order predictions from QCD and indicate a preference for
certain parton distribution functions.

</DOC>
<DOC>
<DOCNO> 118517 </DOCNO>
Turbulence and diffusion: fossil turbulence


  Fossil turbulence processes are central to turbulence, turbulent mixing, and
turbulent diffusion in the ocean and atmosphere, in astrophysics and cosmology,
and in most other natural flows. George Gamov suggested in 1954 that galaxies
might be fossils of primordial turbulence produced by the Big Bang. John Woods
showed that breaking internal waves on horizontal dye sheets in the interior of
the stratified ocean form highly persistent remnants of these turbulent events,
which he called fossil turbulence. The dark mixing paradox of the ocean refers
to undetected mixing that must exist somewhere to explain why oceanic scalar
fields like temperature and salinity are so well mixed, just as the dark matter
paradox of galaxies refers to undetected matter that must exist to explain why
rotating galaxies don't fly apart by centrifugal forces. Both paradoxes result
from sampling techniques that fail to account for the extreme intermittency of
random variables involved in self-similar, nonlinear, cascades over a wide
range of scales; turbulent vorticity for dark mixing, and accreting
small-planetary-mass MACHO number density for dark matter.

</DOC>
<DOC>
<DOCNO> 118604 </DOCNO>
Knots in the outer shells of the planetary nebulae IC 2553 and NGC 5882


  We present images and high-resolution spectra of the planetary nebulae IC
2553 and NGC 5882. Spatio-kinematic modeling of the nebulae shows that they are
composed of a markedly elongated inner shell, and of a less aspherical outer
shell expanding at a considerably higher velocity than the inner one. Embedded
in the outer shells of both nebulae are found several low-ionization knots. In
IC 2553, the knots show a point-symmetric distribution with respect to the
central star: one possible explanation for their formation is that they are the
survivors of pre-existing point-symmetric condensations in the AGB wind, a fact
which would imply a quite peculiar mass-loss geometry from the giant
progenitor. In the case of NGC 5882, the lack of symmetry in the distribution
of the observed low-ionization structures makes it possible that they are the
result of in situ instabilities.

</DOC>
<DOC>
<DOCNO> 118870 </DOCNO>
Testing the Gaussianity of the COBE-DMR data with spherical wavelets


  We investigate the Gaussianity of the 4-year COBE-DMR data (in HEALPix
pixelisation) using an analysis based on spherical Haar wavelets. We use all
the pixels lying outside the Galactic cut and compute the skewness, kurtosis
and scale-scale correlation spectra for the wavelet coefficients at each scale.
We also take into account the sensitivity of the method to the orientation of
the input signal. We find a detection of non-Gaussianity at $> 99$ per cent
level in just one of our statistics. Taking into account the total number of
statistics computed, we estimate that the probability of obtaining such a
detection by chance for an underlying Gaussian field is 0.69. Therefore, we
conclude that the spherical wavelet technique shows no strong evidence of
non-Gaussianity in the COBE-DMR data.

</DOC>
<DOC>
<DOCNO> 101449 </DOCNO>
Cohomology and projectivity of modules for finite group schemes


  Let G be a finite group scheme over an algebraically closed field of positive
characteristic. Assume further that the connected component of G is unipotent.
It is shown that the projectivity of a rational G-module can be detected on a
family of closed subgroups. It is further shown that nilpotent cohomology or
extension classes can be detected on this family of subgroups.

</DOC>
<DOC>
<DOCNO> 99375 </DOCNO>
The kernel of Dirac operators on $\S^3$ and $\R^3$


  In this paper we describe an intrinsically geometric way of producing
magnetic fields on $\S^3$ and $\R^3$ for which the corresponding Dirac
operators have a non-trivial kernel. In many cases we are able to compute the
dimension of the kernel. In particular we can give examples where the kernel
has any given dimension. This generalizes the examples of Loss and Yau (Commun.
Math. Phys. 104 (1986) 283-290).

</DOC>
<DOC>
<DOCNO> 83130 </DOCNO>
DLV - A System for Declarative Problem Solving


  DLV is an efficient logic programming and non-monotonic reasoning (LPNMR)
system with advanced knowledge representation mechanisms and interfaces to
classic relational database systems.
  Its core language is disjunctive datalog (function-free disjunctive logic
programming) under the Answer Set Semantics with integrity constraints, both
default and strong (or explicit) negation, and queries. Integer arithmetics and
various built-in predicates are also supported.
  In addition DLV has several frontends, namely brave and cautious reasoning,
abductive diagnosis, consistency-based diagnosis, a subset of SQL3, planning
with action languages, and logic programming with inheritance.

</DOC>
<DOC>
<DOCNO> 119961 </DOCNO>
Detection of a spectroscopic transit by the planet orbiting the star


  We report the first detection of a planetary transit by spectroscopic
measurements. We have detected the distortion of the stellar line profiles
during a planetary transit. With the ELODIE spectrograph we took a sequence of
high precision radial velocities of the star HD209458 at time of a transit of
its planet. We detected an anomaly in the residuals of the orbit. The shape and
the amplitude of the anomaly are modeled as a change of the mean stellar line
profile resulting from the planet crossing the disk of the rotating star. The
planetary orbit is in the same direction as the stellar rotation. Using the
photometric transit to constrain the timing and the impact parameters of the
transit, we measure an angle alpha=3.9d between the orbital plane and the
apparent equatorial plane as well as a vsini=3.75(+-)1.25 kms-1. With
additional constrains on the inclination of the star and on the statistics of
the line of sight distribution, we can set an upper limit of 30d to the angle
between the orbital plane and the stellar equatorial plane.

</DOC>
<DOC>
<DOCNO> 8068 </DOCNO>
Numerical Simulation of Grain Boundary Grooving By Level Set Method


  A numerical investigation of grain-boundary grooving by means of a Level Set
method is carried out. An idealized polygranular interconnect which consists of
grains separated by parallel grain boundaries aligned normal to the average
orientation of the surface is considered. The surface diffusion is the only
physical mechanism assumed. The surface diffusion is driven by surface
curvature gradients, and a fixed surface slope and zero atomic flux are assumed
at the groove root. The corresponding mathematical system is an initial
boundary value problem for a two-dimensional Hamilton-Jacobi type equation. The
results obtained are in good agreement with both Mullins' analytical "small
slope" solution of the linearized problem (W.W. Mullins, 1957) (for the case of
an isolated grain boundary) and with solution for the periodic array of grain
boundaries (S.A. Hackney, 1988).

</DOC>
<DOC>
<DOCNO> 68475 </DOCNO>
Theory of Heavy Baryon Decay


  We discuss various topics in the theory of heavy baryon decays. Among these
are recent applications of the Relativistic Three Quark Model to semileptonic,
nonleptonic, one-pion and one-photon transitions among heavy baryons, new
higher order perturbative results on the correlator of two heavy baryon
currents and on the semi-inclusive decay $\Lambda_b \to X_c + D_s^{(*)-}$.

</DOC>
<DOC>
<DOCNO> 84093 </DOCNO>
Creation of an Open Universe from Valley Bounce


  It appears difficult to construct a simple model for an open universe based
on the one bubble inflationary scenario. The reason is that one needs a large
mass to avoid the tunneling via the Hawking Moss solution and a small mass for
successful slow-rolling. However, Rubakov and Sibiryakov suggest that the
Hawking Moss solution is not a solution for the false vacuum decay process
since it does not satisfy the boundary condition. Hence, we have reconsidered
the arguments for the defect of the simple polynomial model. We find the valley
bounce belonging to a valley line in the functional space represents the decay
process instead of the Hawking Moss solution. The point is that the valley
bounce gives the appropriate initial condition for the inflation. We show an
open inflation model can be constructed within the polynomial form of the
potential so that the fluctuations can be reconciled with the observations.

</DOC>
<DOC>
<DOCNO> 69822 </DOCNO>
Parapositronium Decay and Dispersion Relations


  Positronium decay rates are computed at the one-loop level, using
convolution-type factorized amplitudes. The dynamics of this factorization is
probed with dispersion relations, showing that unallowed approximations are
usually made, and some ordre alpha^2 corrections missed. Further, we discuss
the relevance of the Schrodinger wavefunction as the basis for perturbative
calculations. Finally, we apply our formalism to the parapositronium two-photon
decay.

</DOC>
<DOC>
<DOCNO> 69500 </DOCNO>
The Very Low Energy Solar Flux of Electron and Heavy-Flavor Neutrinos


  We calculate the thermal flux of low-energy solar neutrinos and antineutrinos
of all flavors arising from a variety of neutrino pair processes: Compton
production (including plasmon-pole diagrams), neutral current decay of
thermally populated nuclear states, plasmon decay, and electron transitions
from free to atomic bound states. The resulting flux density per flavor is
significant (10E8-10E9/cm2/sec/MeV) below about 5 keV, and the distributions
fill much of the valley between the high-energy edge of the cosmic background
neutrino spectrum and the low energy tails of the pp-chain electron neutrino
and terrestrial electron antineutrino spectra. Thermal neutrinos carry
information on the solar core temperature distribution and on heavy flavor
masses in the range of 1 keV. The detection of these neutrinos is a daunting
but interesting challenge.

</DOC>
<DOC>
<DOCNO> 11799 </DOCNO>
Optical creation of vibrational intrinsic localized modes in anharmonic


  Using an efficient optimal control scheme to determine the exciting fields,
we theoretically demonstrate the optical creation of vibrational intrinsic
localized modes (ILMs) in anharmonic perfect lattices with realistic
interatomic potentials. For systems with finite size, we show that ILMs can be
excited directly by applying a sequence of femtosecond visible laser pulses at
THz repetition rates. For periodic lattices, ILMs can be created indirectly via
decay of an unstable extended lattice mode which is excited optically either by
a sequence of pulses as described above or by a single picosecond far-infrared
laser pulse with linearly chirped frequency. In light of recent advances in
experimental laser pulse shaping capabilities, the approach is experimentally
promising.

</DOC>
<DOC>
<DOCNO> 40611 </DOCNO>
Search for Neutral Higgs Bosons of the Minimal Supersymmetric Standard


  A search for the lightest neutral CP-even and the neutral CP-odd Higgs bosons
of the Minimal Supersymmetric Standard Model is performed using 233.2 pb-1 of
integrated luminosity collected with the L3 detector at LEP at centre-of-mass
energies 192-202 GeV. No signal is observed and lower mass limits are given as
a function of tan(beta) for two scalar top mixing hypotheses. For tan(beta)
greater than 0.8, they are mh > 83.4 GeV and mA > 83.8 GeV at 95 % confidence
level.

</DOC>
<DOC>
<DOCNO> 123189 </DOCNO>
Gravitational lensing in eclipsing binary stars


  I consider the effect of the gravitational deflection of light upon the light
curves of eclipsing binary stars, focussing mainly upon systems containing at
least one white dwarf component. In absolute terms the effects are small,
however they are strongest at the time of secondary eclipse when the white
dwarf transits its companion, and act to reduce the depth of this feature. If
not accounted for, this may lead to under-estimation of the radius of the white
dwarf compared to that of its companion. I show that the effect is significant
for plausible binary parameters, and that it leads to ~25% reduction in the
transit depth in the system KPD 1930+2752. The reduction of eclipse depth is
degenerate with the stellar radius ratio, and therefore cannot be used to
establish the existence of lensing. A second order effect of the light bending
is to steepen the ingress and egress features of the secondary eclipse relative
to the primary eclipse, although it will be difficult to see this in practice.
I consider also binaries containing neutron stars and black-holes. I conclude
that, although relatively large effects are possible in such systems, a
combination of rarity, faintness and intrinsic variability make it unlikely
that lensing will be detectable in them.

</DOC>
<DOC>
<DOCNO> 150874 </DOCNO>
Quantum Inconsistency of Einstein Supergravity


  We show that N=1, D=4 Einstein-frame supergravity is inconsistent at one loop
because of an anomaly in local supersymmetry transformations. A Jacobian must
be added to the Einstein-frame Lagrangian to cancel this anomaly. We show how
the Jacobian arises from the super-Weyl field redefinition that takes the
superspace Lagrangian to the Einstein frame. We present an explicit example
which demonstrates that the Jacobian is necessary for one-loop scattering
amplitudes to be frame independent.

</DOC>
<DOC>
<DOCNO> 152149 </DOCNO>
No-go theorem for gravivector and graviscalar on the brane


  We prove the no-go theorem that the gravivector $(h_{5\mu})$ and graviscalar
$(h_{55})$ cannot have any on-shell propagation on the Randall-Sundrum (RS)
brane. For this purpose, we analyze all of their linearized equations with the
de Donder gauge (5D transverse-tracefree gauge).
  But we do not introduce any matter source. We use the Z$_2$-symmetry argument
and their ($h_{5\mu}, h_{55}$) compatibility conditions with the tensor
$h_{\mn}$-equation. It turns out that $h_{55}$ does not have any bulk (massive)
and brane (massless) propagations. Although $h_{5\mu}$ has a sort of massive
propagations, they do not belong to the physical solution. Hence we confirm
that the Randall-Sundrum gauge suffices the on-shell brane physics.

</DOC>
<DOC>
<DOCNO> 85440 </DOCNO>
Refractive gravitational waves and quantum fluctuations


  Refractive gravitational waves are a generalisation of impulsive waves on a
null hypersurface in which the metric is discontinuous but a weaker continuity
condition for areas holds. A simple example of a plane wave is examined in
detail and two arguments are given that this should be considered a solution of
Einstein's vacuum field equations. The study of these waves is motivated by
quantum gravity, where the refractive plane waves are considered as elementary
quantum fluctuations and the `area geometry' of a null hypersurface plays a
primary role.

</DOC>
<DOC>
<DOCNO> 170199 </DOCNO>
Three dimensional time and energy operators and an uncertainty relation


  Three dimensional time and energy operators are introduced and an uncertainty
relation between them is proved.

</DOC>
<DOC>
<DOCNO> 99805 </DOCNO>
Group Cohomology and Gauge Equivalence of some Twisted Quantum Doubles


  Dijkgraaf, Pasquier and Roche introduced twisted quantum doubles of a finite
group in the context of conformal field theory. We study equivalences that
arise among the braided monoidal categories associated to these quantum
doubles, especially in the commutative case. This involves a close study of the
cohomology of various complexes introduced by Eilenberg-MacLane. We show among
other things that an equivalence of braided monoidal categories is the same as
gauge equivalence of the corresponding quantum doubles, and that an invariant
for an equivalence class is given by a metabolic quadratic space.

</DOC>
<DOC>
<DOCNO> 170096 </DOCNO>
Optimal strategies for sending information through a quantum channel


  Quantum states can be used to encode the information contained in a
direction, i.e., in a unit vector. We present the best encoding procedure when
the quantum state is made up of $N$ spins (qubits). We find that the quality of
this optimal procedure, which we quantify in terms of the fidelity, depends
solely on the dimension of the encoding space. We also investigate the use of
spatial rotations on a quantum state, which provide a natural and less
demanding encoding. In this case we prove that the fidelity is directly related
to the largest zeros of the Legendre and Jacobi polynomials. We also discuss
our results in terms of the information gain.

</DOC>
<DOC>
<DOCNO> 11306 </DOCNO>
Fluctuations of the free energy in the REM and the p-spin SK models


  We consider the random fluctuations of the free energy in the $p$-spin
version of the Sherrington-Kirkpatrick model in the high temperature regime.
Using the martingale approach of Comets and Neveu as used in the standard SK
model combined with truncation techniques inspired by a recent paper by
Talagrand on the $p$-spin version, we prove that (for $p$ even) the random
corrections to the free energy are on a scale $N^{-(p-2)/4}$ only, and after
proper rescaling converge to a standard Gaussian random variable. This is shown
to hold for all values of the inverse temperature, $\b$, smaller than a
critical $\b_p$. We also show that $\b_p\to \sqrt{2\ln 2}$ as $p\uparrow
+\infty$. Additionally we study the formal $p\uparrow +\infty$ limit of these
models, the random energy model. Here we compute the precise limit theorem for
the partition function at {\it all} temperatures. For $\b<\sqrt{2\ln2}$,
fluctuations are found at an {\it exponentially small} scale, with two distinct
limit laws above and below a second critical value $\sqrt{\ln 2/2}$: For $\b$
up to that value the rescaled fluctuations are Gaussian, while below that there
are non-Gaussian fluctuations driven by the Poisson process of the extreme
values of the random energies. For $\b$ larger than the critical $\sqrt{2\ln
2}$, the fluctuations of the logarithm of the partition function are on scale
one and are expressed in terms of the Poisson process of extremes. At the
critical temperature, the partition function divided by its expectation
converges to 1/2.

</DOC>
<DOC>
<DOCNO> 150833 </DOCNO>
On the confining potential in 4d $SU(N_c)$ gauge theory with dilaton


  Using the formal analogy between the Dick superstring inspired model of
ref.[6] and the problem of building of Eguchi Hanson metric in 4d N=2 harmonic
superspace (hs), we derive a general formula for the quark-quark interaction
potential V(r) including the Dick confining potential. The interquark potential
V(r) depends on the dilaton-gluon coupling and may be related to the
parameterization of confinement by the quark and gluon vacuum condensates. It
is also shown how the axion field may be incorporated in agreement with 10d
type IIB superstring requirements. Others features are also discussed.

</DOC>
<DOC>
<DOCNO> 8748 </DOCNO>
BEC for a Coupled Two-type Hard Core Bosons Model


  We study a solvable model of two types hard core Bose particles. A complete
analysis is given of its equilibrium states including the proof of existence of
Bose-Einstein condensation. The plasmon frequencies and the quantum normal
modes corresponding to these frequencies are rigorously constructed. In
particular we show a two-fold degeneracy of these frequencies. We show that all
this results from spontaneous gauge symmetry breakdown.

</DOC>
<DOC>
<DOCNO> 170519 </DOCNO>
Entangled quantum states as direction indicators


  We consider the use of N spin-1/2 particles for indicating a direction in
space. If N>2, their optimal state is entangled. For large N, the mean square
error decreases as N^{-2} (rather than N^{-1} for parallel spins).

</DOC>
<DOC>
<DOCNO> 80626 </DOCNO>
Improved Gauge Actions on Anisotropic Lattices I


  On anisotropic lattices with the anisotropy $\xi=a_\sigma/a_\tau$ the
following basic parameters are calculated by perturbative method: (1) the
renormalization of the gauge coupling in spatial and temporal directions,
$g_\sigma$ and $g_\tau$, (2) the $\Lambda$ parameter, (3) the ratio of the
renormalized and bare anisotropy $\eta=\xi/\xi_B$ and (4) the derivatives of
the coupling constants with respect to $\xi$, $\partial g_\sigma^{-2}/\partial
\xi$ and $\partial g_\tau^{-2}/\partial \xi$. We employ the improved gauge
actions which consist of plaquette and six-link rectangular loops, $c_0 P(1
\times 1)_{\mu \nu} + c_1 P(1 \times 2)_{\mu \nu}$. This class of actions
covers Symanzik, Iwasaki and DBW2 actions. The ratio $\eta$ shows an impressive
behavior as a function of $c_{1}$, i.e.,$\eta>1$ for the standard Wilson and
Symanzik actions, while $\eta<1$ for Iwasaki and DBW2 actions. This is
confirmed non-perturbatively by numerical simulations in weak coupling regions.
The derivatives $\partial g^{-2}_{\tau}/\partial \xi$ and $\partial
g^{-2}_{\sigma}/\partial \xi$ also changes sign as $-c_{1}$ increases. For
Iwasaki and DBW2 actions they become opposite sign to those for standard and
Symanzik actions. However, their sum is independent of the type of actions due
to Karsch's sum rule.

</DOC>
<DOC>
<DOCNO> 170005 </DOCNO>
Teleportation of the Relativistic Quantum Field


  The process of teleportation of a completely unknown one-particle state of a
free relativistic quantum field is considered. In contrast to the
non-relativistic quantum mechanics, the teleportation of an unknown state of
the quantum field cannot be in principle described in terms of a measurement in
a tensor product of two Hilbert spaces to which the unknown state and the state
of the EPR-pair belong. The reason is of the existence of a cyclic (vacuum)
state common to both the unknown state and the EPR-pair. Due to the common
vacuum vector and the microcausality principle (commutation relations for the
field operators), the teleportation amplitude contains inevitably contributions
which are irrelevant to the teleportation process. Hence in the relativistic
theory the teleportation in the sense it is understood in the non-relativistic
quantum mechanics proves to be impossible because of the impossibility of the
realization of the appropriate measurement as a tensor product of the
measurements related to the individual subsystems so that one can only speak of
the amplitude of the propagation of the field as a whole.

</DOC>
<DOC>
<DOCNO> 8531 </DOCNO>
Critical behaviour of annihilating random walk of two species with


  The $A+A\to 0$, $B+B\to 0 $ process with exclusion between the different
kinds is investigated here numerically. Before treating this model explicitly,
we study the generalized Domany-Kinzel cellular automaton model of Hinrichsen
on the line of the parameter space where only compact clusters can grow. The
simplest version is treated with two absorbing phases in addition to the active
one. The two kinds of kinks which arise in this case do not react, leading to
kinetics differing from standard annihilating random walk of two species. Time
dependent simulations are presented here to illustrate the differences caused
by exclusion in the scaling properties of usually discussed characteristic
quantities. The dependence on the density and composition of the initial state
is most apparent. Making use of the parallelism between this process and
directed percolation limited by a reflecting parabolic surface we argue that
the two kinds of kinks exert marginal perturbation on each other leading to
deviations from standard annihilating random walk behavior.

</DOC>
<DOC>
<DOCNO> 116741 </DOCNO>
Experience with the Pep-II RF System at High Beam Currents


  The PEP-II B Factory Low-Level RF System (LLRF) is a fully programmable VXI
based design running under an EPICS control environment. Several RF feedback
loops are used to control longitudinal coupled-bunch modes driven by the
accelerating mode of the RF cavities. This paper updates the performance of the
LLRF system as beam currents reach design levels. Modifications which enhance
the stability, diagnostics, and overall operational performance are described.
Recent data from high current operation is included.

</DOC>
<DOC>
<DOCNO> 11019 </DOCNO>
Origin of Critical Behavior in Ethernet Traffic


  We perform a simplified Ethernet traffic simulation in order to clarify the
physical mechanism of the phase transition behavior which has been
experimentally observed in the flow density fluctuation of Internet traffic. In
one phase traffics from nodes connected with an Ethernet cable are mixed, and
in the other phase, the nodes alternately send bursts of packets. The
competition of sending packets among nodes and the binary exponential back-off
algorithm are revealed to play important roles in producing $1/f$ fluctuations
at the critical point.

</DOC>
<DOC>
<DOCNO> 118809 </DOCNO>
Mid-infrared ISO spectroscopy of NGC 4945


  We have observed the central region of the nearby starburst galaxy NGC4945
with the mid-infrared spectrometers SWS and PHT-S aboard ISO. We do not find
any evidence for the existence of the powerful AGN, inferred from hard X-ray
observations. The upper limits on our AGN tracers [NeV] 14.32um & 24.32um and
[NeVI] 7.65um imply an A(V)>160 towards the NLR, assuming the NLR to be of
equal strength as in the Circinus galaxy. Other possibilities are discussed.
The starburst excitation indicators [NeIII]15.56um/[NeII]12.81um and
L(bol)/L(lyc) suggest that the starburst in the central region is at least
5x10^6 yrs old, and that it accounts for at least half of the nuclear
bolometric luminosity. The starburst might well power the entire bolometric
luminosity, but the available constraints are also consistent with an up to 50%
contribution of the embedded AGN. With PHT-S, at a resolution of approximately
90, we detect strong absorption features of water ice, and, for the first time
in an external galaxy, of CO_2 and CO. The same PHT-S spectrum also reveals
strong emission from the family of PAH features. Finally, we have observed and
detected several pure rotational and ro-vibrational H_2 lines, two of which,
the (0-0) S(0) & S(1) lines, allow us to determine the excitation temperature
(160K) and warm H_2 mass (2.4x10^7 Msun). The low excitation temperature shows
Orion-like shocks not to be representative for the entire emission of the
central region of the galaxy and fairly normal PDRs to be perhaps more typical.

</DOC>
<DOC>
<DOCNO> 85582 </DOCNO>
Spectrum of Charged Black Holes - The Big Fix Mechanism Revisited


  Following an earlier suggestion of the authors(gr-qc/9607030), we use some
basic properties of Euclidean black hole thermodynamics and the quantum
mechanics of systems with periodic phase space coordinate to derive the
discrete two-parameter area spectrum of generic charged spherically symmetric
black holes in any dimension. For the Reissner-Nordstrom black hole we get
$A/4G\hbar=\pi(2n+p+1)$, where the integer p=0,1,2,.. gives the charge
spectrum, with $Q=\pm\sqrt{\hbar p}$. The quantity $\pi(2n+1)$, n=0,1,... gives
a measure of the excess of the mass/energy over the critical minimum (i.e.
extremal) value allowed for a given fixed charge Q. The classical critical
bound cannot be saturated due to vacuum fluctuations of the horizon, so that
generically extremal black holes do not appear in the physical spectrum.
Consistency also requires the black hole charge to be an integer multiple of
any fundamental elementary particle charge: $Q= \pm me$, m=0,1,2,.... As a
by-product this yields a relation between the fine structure constant and
integer parameters of the black hole -- a kind of the Coleman big fix mechanism
induced by black holes. In four dimensions, this relationship is
$e^2/\hbar=p/m^2$ and requires the fine structure constant to be a rational
number. Finally, we prove that the horizon area is an adiabatic invariant, as
has been conjectured previously.

</DOC>
<DOC>
<DOCNO> 71977 </DOCNO>
Equation of state of strongly coupled Hamiltonian lattice QCD at finite


  We calculate the equation of state of strongly coupled Hamiltonian lattice
QCD at finite density by constructing a solution to the equation of motion
corresponding to an effective Hamiltonian using Wilson fermions. We find that
up to and beyond the chiral symmetry restoration density the pressure of the
quark Fermi sea can be negative indicating its mechanical instability. This
result is in qualitative agreement with continuum models and should be
verifiable by future numerical simulations.

</DOC>
<DOC>
<DOCNO> 169871 </DOCNO>
Simple computer model for the quantum Zeno effect


  This paper presents a simple model for repeated measurement of a quantum
system: the evolution of a free particle, simulated by discretising the
particle's position. This model is easily simulated by computer and provides a
useful arena to investigate the effects of measurement upon dynamics, in
particular the slowing of evolution due to measurement (the `quantum Zeno
effect'). The results of this simulation are discussed for two rather different
sorts of measurement process, both of which are (simplified forms of)
measurements used in previous simulations of position measurement. A number of
interesting results due to measurement are found, and the investigation casts
some light on previous disagreements about the presence or absence of the Zeno
effect.

</DOC>
<DOC>
<DOCNO> 174489 </DOCNO>
The Halo of 14Be


  The two-neutron halo nucleus 14Be has been investigated in a kinematically
complete measurement of the fragments (12Be and neutrons) produced in
dissociation at 35 MeV/nucleon on C and Pb targets. Two-neutron removal
cross-sections, neutron angular distributions and invariant mass spectra
characteristic of a halo were observed and the electromagnetic (EMD)
contributions deduced. Comparison with three-body model predictions indicate
that the halo wavefunction contains a large 2s1/2^2 admixture. The EMD
invariant mass spectrum exhibited a relatively narrow structure near threshold
(Edecay=1.8+/-0.1 MeV, Gamma = 0.8+/-0.4 MeV) consistent with a soft-dipole
excitation.

</DOC>
<DOC>
<DOCNO> 7625 </DOCNO>
Quantitative Description of Thermodynamics of Layered Magnets in a Wide


  The thermodynamics of layered antiferro- and ferromagnets with a weak
interlayer coupling and/or easy-axis anisotropy is investigated. A crossover
from an isotropic 2D-like to 3D Heisenberg (or 2D Ising) regime is discussed
within the renormalization group (RG) analysis. Analytical results for the the
(sublattice) magnetization and the ordering temperature are derived are
obtained in different regimes. Numerical calculations on the base of the
equations obtained yield a good agreement with experimental data on La2CuO4 and
layered perovskites. Corresponding results for the Kosterlitz-Thouless and
Curie (N\'eel) temperatures in the case of the easy-plane anisotropy are
derived.

</DOC>
<DOC>
<DOCNO> 85502 </DOCNO>
Tests of strong-field gravity and gravitational radiation damping in


  This talk reviews the constraints imposed by binary-pulsar data on gravity
theories, and notably on "scalar-tensor" theories which are the most natural
alternatives to general relativity. Because neutron stars have a strong
gravitational binding energy, binary-pulsar tests are qualitatively different
from solar-system experiments: They have the capability of probing models which
are indistinguishable from general relativity in weak gravitational field
conditions. Besides the two most precise binary-pulsar experiments, in the
systems B1913+16 and B1534+12, we also present the results of the various
"null" tests of general relativity provided by several neutron star-white dwarf
binaries, notably those of gravitational radiation damping. [The main interest
of this very short paper is its figure, which also takes into account the
"strong equivalence principle" tests.]

</DOC>
<DOC>
<DOCNO> 169791 </DOCNO>
From Einstein Nonlocality to Von Neumann Reality


  Recent nonlocality results support a new picture of reality built on the
ideas of John von Neumanm

</DOC>
<DOC>
<DOCNO> 178742 </DOCNO>
Semiempirical Shell Model Masses with Magic Number Z=126 for Translead


  A semiempirical shell model mass equation based on magic number Z=126 and
applicable to translead elements with N smaller or equal to 126 is presented.
For alpha decay energies the equation is shown to have a high predictive power
and an rms deviation from the data of about 100 keV. The rms deviations for
masses and other mass differences are between about 200 and 300 keV.

</DOC>
<DOC>
<DOCNO> 120791 </DOCNO>
Multi-Frequency Analysis of the New Wide-Separation Gravitational Lens


  We report the discovery of a new two-image gravitational lens candidate. The
system RX J0921+4529 contains two z_s=1.66 quasars separated by 6."93 with an H
band magnitude difference of $\Delta m=1.39$. The HST NIC2 H band images reveal
an H=18.2 spiral galaxy between the quasar images, which is probably a member
of a z_l=0.32 X-ray cluster centered on the field. We detect an extended source
near the fainter quasar image but not in the brighter image. If this extended
source is the host galaxy of the fainter quasar, then the system is a binary
quasar rather than a gravitational lens. VLA observations at 3.6 cm reveal
emission from the lens galaxy at the flux level of 1 mJy and a marginal
detection of the brighter quasar.

</DOC>
<DOC>
<DOCNO> 100797 </DOCNO>
On the Uniqueness of the Chentsov Metric in Quantum Information Geometry


  We show that, in finite dimensions, the only monotone metrics for which the
(+1) and (-1) affine connections are mutually dual are constant multiples of
Bogoliubov-Kubo-Mori metric

</DOC>
<DOC>
<DOCNO> 69445 </DOCNO>
Towards a unified theory of gauge and Yukawa interactions


  It is suggested to combine gauge and Yukawa interactions into one expression
involving the generalized Dirac operator associated with a superconnection
$D+L$, $L$ being linked to the Higgs field (one doublet). We advocate a version
of the Minimal Standard Model where the Higgs field gives masses to the
neutrinos and a CKM matrix to the leptons.

</DOC>
<DOC>
<DOCNO> 68456 </DOCNO>
Dynamical Screening and Radiative Parton Energy Loss in a Quark-gluon


  Dynamical screening in the magnetic part of the one-gluon exchange
interaction is included in the study of radiative energy loss of a fast parton
propagating inside a quark-gluon plasma. As a result the final radiative energy
loss is about twice as large as when only the electric part of one-gluon
exchange interaction is considered. A non-perturbative magnetic screening mass
is also used in the estimate of the mean-free-path of parton scattering in a
hot QCD matter.

</DOC>
<DOC>
<DOCNO> 10074 </DOCNO>
Magnetization of ferrofluids with dipolar interactions - a Born--Mayer


  For ferrofluids that are described by a system of hard spheres interacting
via dipolar forces we evaluate the magnetization as a function of the internal
magnetic field with a Born--Mayer technique and an expansion in the dipolar
coupling strength. Two different approximations are presented for the
magnetization considering different contributions to a series expansion in
terms of the volume fraction of the particles and the dipolar coupling
strength.

</DOC>
<DOC>
<DOCNO> 9872 </DOCNO>
Nonexponential Relaxation of Magnetization at the Resonant Tunneling


  Nonexponential relaxation of magnetization at resonant tunneling points of
nanoscale molecular magnets is interpreted to be an effect of fluctuating
random field around the applied field. We demonstrate such relaxation in
Langevin equation analysis and clarify how the initial relaxation (square-root
time) changes to the exponential decay. The scaling properties of the
relaxation are also discussed.

</DOC>
<DOC>
<DOCNO> 83314 </DOCNO>
Dimension-Dependent behavior in the satisfability of random k-Horn


  We determine the asymptotical satisfiability probability of a random
at-most-k-Horn formula, via a probabilistic analysis of a simple version,
called PUR, of positive unit resolution. We show that for k=k(n)->oo the
problem can be ``reduced'' to the case k(n)=n, that was solved in
cs.DS/9912001. On the other hand, in the case k= a constant the behavior of PUR
is modeled by a simple queuing chain, leading to a closed-form solution when
k=2. Our analysis predicts an ``easy-hard-easy'' pattern in this latter case.
Under a rescaled parameter, the graphs of satisfaction probability
corresponding to finite values of k converge to the one for the uniform case, a
``dimension-dependent behavior'' similar to the one found experimentally by
Kirkpatrick and Selman (Science'94) for k-SAT. The phenomenon is qualitatively
explained by a threshold property for the number of iterations of PUR makes on
random satisfiable Horn formulas.

</DOC>
<DOC>
<DOCNO> 102519 </DOCNO>
Counting Singular Plane Curves Via Hilbert Schemes


  We give a method of counting the number of curves with a given type of
singularity in a suitably ample linear series on a smooth surface using
punctual Hilbert schemes. The types of singulaties for which our methods
suffice include the topological type with local equation x^a +y^b with b-1 < a
< 3b+1. We work out the example of curves with the analytic type of singularity
with local equation x^2+y^n for 1<n<9.

</DOC>
<DOC>
<DOCNO> 150358 </DOCNO>
Dirac Monopole in Non-Commutative Space


  We consider static U(1) monopole in non-commutative space. Up to the second
order in the non-commutativity scale $\theta$, we find no non-trivial
corrections to the Dirac solution, the monopole mass remains infinite. We argue
the same holds for any arbitrary higher order. Some speculation about the
nature of non-commutative spacetime and its relation to the cosmological
constant is made.

</DOC>
<DOC>
<DOCNO> 84702 </DOCNO>
Statistical Entropy of a Stationary Dilaton Black Hole from Cardy


  With Carlip's boundary conditions, a standard Virasoro subalgebra with
corresponding central charge for stationary dilaton black hole obtained in the
low-energy effective field theory describing string is constructed at a Killing
horizon. The statistical entropy of stationary dilaton black hole yielded by
standard Cardy formula agree with its Bekenstein-Hawking entropy only if we
take period $ T$ of function $v$ as the periodicity of the Euclidean black
hole. On the other hand, if we consider first-order quantum correction then the
entropy contains a logarithmic term with a factor $-{1/2}$, which is different
from Kaul and Majumdar's one, $-{3/2}$. We also show that the discrepancy is
not just for the dilaton black hole, but for any one whose corresponding
central change takes the form $\frac{c}{12}= \frac{A_H}{8\pi
G}\frac{2\pi}{\kappa T}$.

</DOC>
<DOC>
<DOCNO> 12865 </DOCNO>
Realistic modeling of strongly correlated electron systems: An


  The LDA+DMFT approach merges conventional band structure theory in the local
density approximation (LDA) with a state-of-the-art many-body technique, the
dynamical mean-field theory (DMFT). This new computational scheme has recently
become a powerful tool for ab initio investigations of real materials with
strong electronic correlations. In this paper an introduction to the basic
ideas and the set-up of the LDA+DMFT approach is given. Results for the
photoemission spectra of the transition metal oxide La_{1-x}Sr_xTiO_3, obtained
by solving the DMFT-equations by quantum Monte-Carlo (QMC) simulations, are
presented and are found to be in very good agreement with experiment. The
numerically exact DMFT(QMC) solution is compared with results obtained by two
approximative solutions, i.e., the iterative perturbation theory and the
non-crossing approximation.

</DOC>
<DOC>
<DOCNO> 118936 </DOCNO>
An Extended View of the Fornax Cluster


  The Multibeam survey at the Parkes Radio Telescope has provided a wealth of
21 cm HI data. We have mosaicked ten standard HIPASS cubes to produce a
datacube approximately 25 deg x 25 deg in size, centred on NGC1399, the optical
centre of the Fornax Cluster. Some properties of the initial approx. 80
galaxies identified in HI are described.
  In the optical, Ferguson's Fornax Cluster Catalogue (FCC) identified 340
likely member galaxies in the central 40 sq.deg. In the radio we have detected
a more uniform sheet of about 80 galaxies at the cluster velocity extending up
to 15 deg from the cluster centre. At the cluster distance of about 15 Mpc,
this corresponds to an elongated large-scale structure (LSS) more than 7 Mpc in
extent.
  Galaxies were detected to a lower mass limit of 1x10^8M_sun and fewer than 25
of these were within the central 40 sq.deg, suggesting considerable HI
depletion of galaxies in the centre of the cluster. Further, these results
strongly indicate that HI surveys do not readily identify galaxy clusters.

</DOC>
<DOC>
<DOCNO> 13606 </DOCNO>
Vortex charge in mesoscopic superconductors


  The electric charge density in mesoscopic superconductors with circular
symmetry, i.e. disks and cylinders, is studied within the phenomenological
Ginzburg-Landau approach. We found that even in the Meissner state there is a
charge redistribution in the sample which makes the sample edge become
negatively charged. In the vortex state there is a competition between this
Meissner charge and the vortex charge which may change the polarity of the
charge at the sample edge with increasing magnetic field. It is shown
analytically that in spite of the charge redistribution the mesoscopic sample
as a whole remains electrically neutral.

</DOC>
<DOC>
<DOCNO> 69998 </DOCNO>
Deconfinement in QCD at Finite Temperature


  We present a simple and intuitive picture for the deconfinement of quarks and
gluons at finite temperature: as the temperature increases, QCD behaves like
QED at T=0. We show this by calculating the QCD coupling constant as a function
of the temperature and of the external momenta used to probe quarks and gluons.

</DOC>
<DOC>
<DOCNO> 121734 </DOCNO>
Distance to the RR Lyrae Star V716 Monocerotis


  We present high quality BVRI CCD photometry of the variable star V716
Monocerotis (= NSV 03775). We confirm it to be an RR Lyrae star of variability
type ab (i.e. a fundamental mode pulsator), and determine its metallicity
([Fe/H] = -1.33 +/- 0.25), luminosity (Mv = 0.80 +/- 0.06), and foreground
reddening (E(B-V) = 0.05-0.17) from the Fourier components of its light curve.
These parameters indicate a distance of 4.1 +/- 0.3 kpc, placing V716 Mon near
the plane of the Galaxy well outside the solar circle. This research was
conducted as part of the 1999 Research Experiences for Undergraduates (REU) and
Practicas de Investigacion en Astronomia (PIA) Programs at Cerro Tololo
Inter-American Observatory (CTIO).

</DOC>
<DOC>
<DOCNO> 40500 </DOCNO>
Charm Hadroproduction at Fermilab E769


  E769 has just recorded on tape the interactions of 500 million pions, kaons,
and protons. A Cerenkov counter and a TRD were used to tag beam particle types
in both positive and negative 250 GeV/c hadron beams. Thin foil Be, Al, Cu, and
W targets were used with a spectrometer including silicon microstrips to look
for charm decay vertices. Preliminary results show D0 --> K- pi+ and D+ --> K-
pi+ pi+ mass peaks. As the event reconstruction progresses on numerous parallel
microprocessors, we intend to explore the pT, xF, A, and flavor dependence of
the production of charmed mesons and baryons.

</DOC>
<DOC>
<DOCNO> 68643 </DOCNO>
Neutrinoless double beta decay with and without Majoron-like boson


  We consider the contributions to the neutrinoless double beta decays in a
$SU(3)_L\otimes U(1)_N$ electroweak model. We show that for a range of the
parameters in the model there are diagrams involving vector-vector-scalar and
trilinear scalar couplings which can be potentially as contributing as the
light massive Majorana neutrino exchange one. We use these contributions to
obtain constraints upon some mass scales of the model, like the masses of the
new charged vector and scalar bosons. We also consider briefly the decay in
which besides the two electrons a Majoron-like boson is emitted.

</DOC>
<DOC>
<DOCNO> 83322 </DOCNO>
Knowledge Theoretic Properties of Topological Spaces


  We study the topological models of a logic of knowledge for topological
reasoning, introduced by Larry Moss and Rohit Parikh. Among our results is a
solution of a conjecture by the formentioned authors, finite satisfiability
property and decidability for the theory of topological models.

</DOC>
<DOC>
<DOCNO> 13316 </DOCNO>
Quantum pump for spin and charge transport in a Luttinger liquid


  We study two different parametric pumps for interacting quantum wires, one
for pumping spin currents, the other for charge currents. We find that the spin
or charge pumped per cycle has a non-universal crossover, depending on pumping
details, between two universal fixed point values of 0 and twice the electronic
spin or charge quantum number. These universal values are independent of
interactions, but the direction of flow between the two values depends on
whether the interactions are repulsive or attractive.

</DOC>
<DOC>
<DOCNO> 11254 </DOCNO>
Random incidence matrices: moments of the spectral density


  We study numerically and analytically the spectrum of incidence matrices of
random labeled graphs on N vertices : any pair of vertices is connected by an
edge with probability p. We give two algorithms to compute the moments of the
eigenvalue distribution as explicit polynomials in N and p. For large N and
fixed p the spectrum contains a large eigenvalue at Np and a semi-circle of
"small" eigenvalues. For large N and fixed average connectivity pN (dilute or
sparse random matrices limit), we show that the spectrum always contains a
discrete component. An anomaly in the spectrum near eigenvalue 0 for
connectivity close to e=2.72... is observed. We develop recursion relations to
compute the moments as explicit polynomials in pN. Their growth is slow enough
so that they determine the spectrum. The extension of our methods to the
Laplacian matrix is given in Appendix.
  Keywords: random graphs, random matrices, sparse matrices, incidence matrices
spectrum, moments

</DOC>
<DOC>
<DOCNO> 179025 </DOCNO>
Liquid-Drop Model and Quantum Resistance Against Noncompact Nuclear


  The importance of quantum effects for exotic nuclear shapes is demonstrated.
Based on the example of a sheet of nuclear matter of infinite lateral
dimensions but finite thickness, it is shown that the quantization of states in
momentum space, resulting from the confinement of the nucleonic motion in the
conjugate geometrical space, generates a strong resistance against such a
confinement and generates restoring forces driving the system towards compact
geometries. In the liquid-drop model, these quantum effects are implicitly
included in the surface energy term, via a choice of interaction parameters, an
approximation that has been found valid for compact shapes, but has not yet
been scrutinized for exotic shapes.

</DOC>
<DOC>
<DOCNO> 101241 </DOCNO>
Operational Galois adjunctions


  We present a detailed synthetic overview of the utilisation of categorical
techniques in the study of order structures together with their applications in
operational quantum theory. First, after reviewing the notion of residuation
and its implementation at the level of quantaloids we consider some standard
universal constructions and the extension of adjunctions to weak morphisms.
Second, we present the categorical formulation of closure operators and
introduce a hierarchy of contextual enrichments of the quantaloid of complete
join lattices. Third, we briefly survey physical state-property duality and the
categorical analysis of derived notions such as causal assignment and the
propagation of properties.

</DOC>
<DOC>
<DOCNO> 152027 </DOCNO>
Topics on Strings, Branes and Calabi-Yau Compactifications


  Basics of some topics on perturbative and non-perturbative string theory are
reviewed. After a mathematical survey of the Standard Model of particle physics
and GUTs, the bosonic string kinematics for the free case and with interaction
is described. The effective action of the bosonic string and the spectrum is
also discussed. Five perturbative superstring theories and their spectra is
briefly outlined. Calabi-Yau three-fold compactifications of heterotic strings
and their relation to some four-dimensional physics are given. T-duality in
closed and open strings are surveyed. D-brane definition is provided and some
of their properties and applications to brane boxes configurations, in
particular to the cube model are discussed. Finally, non-perturbative issues
like S-duality, M-theory, F-theory and basics of their non-perturbative
Calabi-Yau compactifications are considered.

</DOC>
<DOC>
<DOCNO> 9421 </DOCNO>
Observation of the parallel-magnetic-field-induced


  We study the response of a thin superconducting amorphous InO film with
variable oxygen content to a parallel magnetic field. A field-induced
superconductor-insulator transition (SIT) is observed that is very similar to
the one in normal magnetic fields. As the boson-vortex duality, which is the
key-stone of the theory of the field-induced SIT, is obviously absent in the
parallel configuration, we have to draw conclusion about the theory
insufficiency.

</DOC>
<DOC>
<DOCNO> 102275 </DOCNO>
Arnold's Diffusion in nearly integrable isochronous Hamiltonian systems


  We consider the problem of Arnold's diffusion for nearly integrable
isochronous Hamiltonian systems. We prove a shadowing theorem which improves
the known estimates for the diffusion time. We also develop a new method for
measuring the splitting of the separatrices. As an application we justify, for
three time scales systems, that the splitting is correctly predicted by the
Poincar\'e-Melnikov function.

</DOC>
<DOC>
<DOCNO> 40197 </DOCNO>
Measurement of the branching fractions for B^0 -> D^{*-}pi^+ and B^0 ->


  Using 5.2 fb-1 of e^+e^- annihilation data recorded with the BABAR detector
at the PEP-II storage ring while operating on the Y(4S) resonance, a sample of
fully reconstructed B^0 decays in the hadronic modes B^0 -> D^{*-}pi^+ and B^0
-> D^{*-}rho^+ have been reconstructed. In this paper, a study of these events
is reported, including preliminary measurements of the absolute branching
fractions for these modes, which are found to be B(B^0 -> D^{*-}pi^+) =
(2.9+/-0.3+/-0.3) x 10^{-3} and B(B^0 -> D^{*-}rho^+) = (11.2+/-1.1+/-2.5) x
10^{-3}.

</DOC>
<DOC>
<DOCNO> 151503 </DOCNO>
Fusion in coset CFT from admissible singular-vector decoupling


  Fusion rules for Wess-Zumino-Witten (WZW) models at fractional level can be
defined in two ways, with distinct results. The Verlinde formula yields fusion
coefficients that can be negative. These signs cancel in coset fusion rules,
however. On the other hand, the fusion coefficients calculated from decoupling
of singular vectors are non-negative. They produce incorrect coset fusion
rules, however, when factorisation is assumed. Here we give two prescriptions
that yield the correct coset fusion rules from those found for the WZW models
by the decoupling method. We restrict to the Virasoro minimal models for
simplicity, and because decoupling results are only complete in the $\su(2)$
case.

</DOC>
<DOC>
<DOCNO> 70473 </DOCNO>
On some new warped brane world solutions in higher dimensions


  We present new solutions of higher dimensional Einstein's equations with a
cosmological constant that localize gravity on branes which are transverse to
Ricci-flat manifolds or to homogeneous spaces with topologically non-trivial
solutions of gauge field equations. These solutions are relevant for the
localization of chiral fermions on a brane.

</DOC>
<DOC>
<DOCNO> 71557 </DOCNO>
QCD vacuum structure


  Several issues related to the structure of the QCD vacuum are reviewed. We
concentrate mostly on results concerning instantons and center vortices.

</DOC>
<DOC>
<DOCNO> 69393 </DOCNO>
Can Nucleon Tell Where the Couplings Run?


  The comparison of magnetic moments of neutron and proton reveals three
possible states of a nucleon with the same correction of 0.033 for the central
quarks. This may be interpreted as the contribution of a universal coupling as
the common value where all the running couplings unite.

</DOC>
<DOC>
<DOCNO> 122367 </DOCNO>
Isodensity Statistics on Clustering of High-z Objects in Cosmological


  We discuss the systematic effects arising from the cosmological
redshift-space (geometric) distortion on the statistical analysis of isodensity
contour using high-redshift catalogs. Especially, we present a simple
theoretical model for isodensity statistics in cosmological redshift-space, as
a generalization of the work by Matsubara (1996). The statistical quantities
considered here are the two- and three-dimensional genus of isodensity contour,
the area of surface, the length of contour intersecting with a plane and the
number of the crossing points of isodensity contour on a line. We give useful
analytic formulae for the isodensity statistics, which take into account the
corrections from the geometric distortion, the nonlinear clustering and the
nonlinear velocity distortion phenomenologically. We then demonstrate how the
geometric distortion and the nonlinear corrections alter shapes of the
statistical quantities on the basis of plausible cosmological models. Our
results show that the nonlinear correction can be sensitive to a choice of the
redshift-space coordinate as increasing the redshift. The low-dimensional
quantities such as two-dimensional genus systematically yield anisotropy due to
the geometric and velocity distortions and their angle-dependence shows the
$10\sim20%$ difference of amplitude. Sensitivity for typical high-redshift
samples are estimated in an analytic manner, and the influence of the
light-cone effect for the isodensity statistics is also discussed.

</DOC>
<DOC>
<DOCNO> 150360 </DOCNO>
Generalized two-dimensional Yang-Mills theory is a matrix string theory


  We consider two-dimensional Yang-Mills theories on arbitrary Riemann
surfaces. We introduce a generalized Yang-Mills action, which coincides with
the ordinary one on flat surfaces but differs from it in its coupling to
two-dimensional gravity. The quantization of this theory in the unitary gauge
can be consistently performed taking into account all the topological sectors
arising from the gauge-fixing procedure. The resulting theory is naturally
interpreted as a Matrix String Theory, that is as a theory of covering maps
from a two-dimensional world-sheet to the target Riemann surface.

</DOC>
<DOC>
<DOCNO> 117011 </DOCNO>
New complex variables for equations of ideal barotropic fluid


  We propose new construction of dependent variables for equations of an ideal
barotropic fluid. This construction is based on a direct generalization of the
known connection between Schroedinger equation and a system of Euler-type
equations. The system for two complex-valued functions is derived that is
equivalent to Euler equations. Possible advantages of the proposed formulation
are discussed.

</DOC>
<DOC>
<DOCNO> 13324 </DOCNO>
Comment on ``Analytic Structure of One-Dimensional Localization Theory:


  The low-frequency conductivity of a disordered Fermi gas in one spatial
dimension is governed by the Mott-Berezinskii law $\sigma(\omega) \propto
\omega^2 \ln \omega^2$. In a recent Letter [Phys. Rev. Lett. 84, 1760 (2000)]
A. O. Gogolin claimed that this law is invalid, challenging our basic
understanding of disordered systems and a massive amount of previous
theoretical work. We point out two calculational errors in Gogolin's paper.
Once we correct them, the Mott-Berezinskii formula is fully recovered. We also
present numerical results supporting the Mott-Berezinskii formula but ruling
out that of Gogolin.

</DOC>
<DOC>
<DOCNO> 100651 </DOCNO>
Maps of p-gons with a ring of q-gons


  We study 3-valent maps $M_n(p,q)$ consisting of a ring of $n$ $q$-gons whose
the inner and outer domains are filled by $p$-gons, for $p,q \ge 3$. We
describe a domain in the space of parameters $p$, $q$, and $n$, for which such
a map may exist. With four infinite sequences of maps - prisms $M_p(p \ge
3,4)$, $M_4(4,q \ge 4)$, $M_4(5,5t+2 \ge 7)$, $M_4(5,5t+3 \ge 8)$, we give 20
sporadic ones. The maps whose $p$-gons form two paths are first two infinite
sequences and 5 maps: $M_{28}(7,5)$, $M_{12}(6,5)$, $M_{10}(5,6)$,
$M_{20}(5,7)$, $M_{2}(3,6)$

</DOC>
<DOC>
<DOCNO> 84755 </DOCNO>
A Novel Spin-Statistics Theorem in (2 + 1)d Chern-Simons Gravity


  It has been known for some time that topological geons in quantum gravity may
lead to a complete violation of the canonical spin-statistics relation : there
may exist no connection between spin and statistics for a pair of geons. We
present an algebraic description of quantum gravity in (2 + 1)d based on the
first order formalism of general relativity and show that, although the usual
spin-statistics theorem is not valid, statistics is completely determined by
spin. Hence, a new spin-statistics theorem can be formulated.

</DOC>
<DOC>
<DOCNO> 84400 </DOCNO>
Boost-rotation symmetric spacetimes - review


  Boost-rotation symmetric spacetimes are the only locally asymptotically flat
axially symmetric electrovacuum spacetimes with a further symmetry that are
radiative. They are realized by uniformly accelerated particles of various
kinds or black holes. Their general properties are summarized. Several examples
of boost-rotation symmetric solutions of the Maxwell and Einstein equations are
studied: uniformly accelerated electric and magnetic multipoles, the
Bonnor-Swaminarayan solutions, the C-metric and the spinning C-metric.

</DOC>
<DOC>
<DOCNO> 11201 </DOCNO>
Spin Structure of Many-Body Systems with Two-Body Random Interactions


  We investigate the spin structure of many-fermion systems with a
spin-conserving two-body random interaction. We find a strong dominance of
spin-0 ground states and considerable correlations between energies and wave
functions of low-lying states with different spin, but no indication of
pairing. The spectral densities exhibit spin-dependent shapes and widths, and
depend on the relative strengths of the spin-0 and spin-1 couplings in the
two-body random matrix. The spin structure of low-lying states can largely be
explained analytically.

</DOC>
<DOC>
<DOCNO> 13707 </DOCNO>
The ground state properties of the spin-1/2 transverse Ising chain with


  Using continued fractions we study the ground state properties of the
spin-1/2 Ising chain in a transverse field with periodically varying
interaction strengths and external fields. We consider in detail the chain
having the period of modulation of interactions equals 2 and compare the
results obtained with those corresponding to the spin-1/2 isotropic XY chain in
a transverse field. In contrast to the behaviour of the transverse XY chain,
the transverse Ising chain does not exhibit a step-like magnetization vs. field
dependence caused by the alternation of bonds, its susceptibility exhibits a
logarithmic singularity at the field determined by interaction strengths, and
it is stable with respect to spin-Peierls dimerization.

</DOC>
<DOC>
<DOCNO> 9145 </DOCNO>
Gauge theory of self-similar system


  On the basis of a dilatation invariant Lagrangian, governed equations are
determined for probability density and gauge potential of the non-stationary
self-similar stochastic system. It is shown that an automodel regime is
observed at small time interval determined by the Tsallis' parameter $q>1$. An
exponential falling down happens at large time where the dilatation parameter
and the partial scale tend to constant values.

</DOC>
<DOC>
<DOCNO> 118236 </DOCNO>
Ultra-High-Energy Cosmic Ray Acceleration by Magnetic Reconnection in


  We here investigate the possibility that the ultra-high energy cosmic ray
(UHECR) events observed above the GZK limit are mostly protons accelerated in
econnection sites just above the magnetosphere of newborn millisecond pulsars
which are originated by accretion induced collapse (AIC).

</DOC>
<DOC>
<DOCNO> 119388 </DOCNO>
Radio Galaxy Clustering at z~0.3


  Radio galaxies are uniquely useful as probes of large-scale structure as
their uniform identification with giant elliptical galaxies out to high
redshift means that the evolution of their bias factor can be predicted. As the
initial stage in a project to study large-scale structure with radio galaxies
we have performed a small redshift survey, selecting 29 radio galaxies in the
range 0.19<z<0.45 from a contiguous 40 square degree area of sky. We detect
significant clustering within this sample. The amplitude of the two-point
correlation function we measure is consistent with no evolution from the local
(z<0.1) value. This is as expected in a model in which radio galaxy hosts form
at high redshift and thereafter obey a continuity equation, although the
signal:noise of the detection is too low to rule out other models. Larger
surveys out to z~1 should reveal the structures of superclusters at
intermediate redshifts and strongly constrain models for the evolution of
large-scale structure.

</DOC>
<DOC>
<DOCNO> 170440 </DOCNO>
Quantum teleportation criteria for continuous variables


  We discuss the criteria presently used for evaluating the efficiency of
quantum teleportation schemes for continuous variables. It is argued that the
fidelity criterion used so far has some severe drawbacks, and that a fidelity
value larger than 2/3 is actually required for successful quantum
teleportation. This value has never been reached experimentally so far.

</DOC>
<DOC>
<DOCNO> 151117 </DOCNO>
NDIM achievements: Massive, Arbitrary tensor rank and N-loop insertions


  One of the main difficulties in studying Quantum Field Theory, in the
perturbative regime, is the calculation of D-dimensional Feynman integrals. In
general, one introduces the so-called Feynman parameters and associated with
them the cumbersome parametric integrals. Solving these integrals beyond the
one-loop level can be a difficult task. Negative dimensional integration method
(\ndim{}) is a technique whereby such problem is dramatically reduced. In this
work we present the calculation of two-loop integrals in three diferent cases:
scalar ones with three diferent masses, massless with arbitrary tensor rank,
with N-insertions of a 2-loop diagram.

</DOC>
<DOC>
<DOCNO> 122396 </DOCNO>
BeppoSAX observation of Hercules A and MRC 0625-536


  We present BeppoSAX observations of the two FR I type radio galaxies Hercules
A (3C 348) and MRC 0625-536 in the energy range $0.2 - 200$ keV. Data analysis
shows that the X-ray flux from Hercules A is consistent with a diffuse thermal
plasma emitting at $T \approx 4-5$ keV with a possible, but somewhat uncertain,
contribution of a softer component at $T \approx 3 $ keV. The non thermal
emission from the active nucleus must be significantly smaller than the thermal
one, and no indication of relevant core obscuration by a surrounding torus was
detected. The flux from MRC 0625-536 originates form an extended region and has
been fitted to a thermal law with $T \approx 5.7$ keV and with a column density
consistent with the galactic absorption. A spatially resolved spectral analysis
does not show a relevant variation of the temperature and the metallicity
across the diffuse emission zone. A non thermal spectral component, related to
the nuclear activity, may be present in the innermost region with some possible
amount of local obscuration, contributing $\lapp 10%$ to the total luminosity.
Hard X-ray emission from MRC 0625-536 has been detected in the PDS (15 - 200
keV) that may be related either to its galactic core or to the intracluster
region.

</DOC>
<DOC>
<DOCNO> 169988 </DOCNO>
On a SUSY QM scheme for any linear homogeneous differential equation of


  A formal SUSY QM procedure for any linear homogeneous second-order
differential equation is briefly sketched up and applied to a simple exactly
solvable case

</DOC>
<DOC>
<DOCNO> 40375 </DOCNO>
Bounds on the CP Asymmetry in $b\to s\gamma$ Decays


  We have measured the CP asymmetry A_CP = [BF(b -> s gamma) - BF(bbar -> sbar
gamma)]/ [BF(b -> s gamma) + BF(bbar -> sbar gamma)] to be A_CP = (-0.079 +/-
0.108 +/- 0.022)(1.0 +/- 0.030), implying that, at 90% confidence level, A_CP
lies between -0.27 and +0.10. These limits rule out some extreme non-Standard
Model predictions, but are consistent with most, as well as with the Standard
Model.

</DOC>
<DOC>
<DOCNO> 11244 </DOCNO>
Exact Solution of the Statistical Multifragmentation Model and


  An exact analytical solution of the statistical multifragmentation model is
found in thermodynamic limit. The system of nuclear fragments exhibits a 1-st
order liquid-gas phase transition. The peculiar thermodynamic properties of the
model near the boundary between the mixed phase and the pure gaseous phase are
studied.

</DOC>
<DOC>
<DOCNO> 40655 </DOCNO>
QCD at the Tevatron: Status and Prospects


  I shall review the present status of Tevatron QCD studies, focusing on the
production of jets, vector bosons, photons and heavy quarks. In general there
is good agreement between the results of current calculational tools and the
experimental data. The major areas of discrepancy arise when the input parton
distributions become uncertain (for example, jets at high $E_T$) or when the
momentum scales become relatively small (for example, $b$ production at low
$p_T$). We can look forward to continued improvement in both calculations and
measurements over the next decade. However, fully exploiting the power of the
data will require considerable work, both from the experimentalists who must
understand and publish all the systematic errors and their correlations, and
from the phenomenologists who must understand the level of uncertainty in their
calculations and in the parton distributions.

</DOC>
<DOC>
<DOCNO> 8975 </DOCNO>
Segregation in a competing and evolving population


  We study a recently proposed model in which an odd number of agents are
competing to be in the minority. The agents have one strategy in hand which is
to follow the most recent history. Each agent is also assigned a value p, which
is the probability that an agent will follow the trend. Evolution is introduced
through the modification of the value of p when the performance of an agent
becomes unsatisfactory. We present numerical results for the distribution of p
values in the population as well as the average duration between modifications
at a given p for different values of the parameters in the model. We also point
out the difference between the present model and a slightly modified model in
which a strategy is randomly assigned to every agent initially.

</DOC>
<DOC>
<DOCNO> 99639 </DOCNO>
Quasi-exactly solvable quartic potentials with centrifugal and Coulombic


  PT symmetric complex potential V(r) = - r^4 + i a r^3 + b r^2 + i c r + i d/r
+ e/r^2 is studied. Arbitrarily large multiplets of its closed bound-state
solutions with real energies are shown obtainable quasi-exactly (i.e., with a
certain relationship between their charges and energies) from a single
underlying finite-dimensional secular equation.

</DOC>
<DOC>
<DOCNO> 122740 </DOCNO>
Gravitational lensing and elliptical galaxies


  If the statistics of quasar lensing are to be used to constrain the
cosmological model, the various potential systematic uncertainties in the
deflector population must be accounted for. One ambiguity in the lensing
properties of the dominant deflectors - elliptical galaxies - is their
dynamical normalisation. Assuming they can be modelled as isothermal spheres,
it is shown that their mass normalisation is sufficiently high that current
upper limits on the cosmological constant remain valid, and in fact probably
strengthened, even if ellipticals have significant core radii.

</DOC>
<DOC>
<DOCNO> 102537 </DOCNO>
The non-commutative Specker phenomenon in the uncountable case


  An infinitary version of the notion of free products has been introduced and
investigated by G.Higman. Let G_i (for i in I) be groups and ast_{i in X} G_i
the free product of G_i (i in X) for X Subset I and p_{XY}: ast_{i in Y}
G_{i}->ast_{i in X} G_{i} the canonical homomorphism for X subseteq Y Subset I.
(X Subset I denotes that X is a finite subset of I.) Then, the unrestricted
free product is the inverse limit lim (ast_{i in X} G_i, p_{XY}: X subseteq Y
Subset I). We remark ast_{i in emptyset} G_i= {e} . We prove:
  Theorem: Let F be a free group. Then, for each homomorphism h:lim ast G_i-> F
there exist countably complete ultrafilters u_0,...,u_m on I such that h = h .
p_{U_0 cup ... cup U_m} for every U_0 in u_0, ...,U_m in u_m. If the
cardinality of the index set I is less than the least measurable cardinal, then
there exists a finite subset X_0 of I and a homomorphism overline {h}: ast_{i
in X_0}G_i-> F such that h= overline {h} . p_{X_0}, where p_{X_0}: lim ast
G_i->ast_{i in X_0}G_i is the canonical projection.

</DOC>
<DOC>
<DOCNO> 120354 </DOCNO>
Probing large-distance higher-dimensional gravity with Cosmic Microwave


  It has been recently argued that higher dimensional gravity theories may
manifest themselves not only at short microscopic distances but also at large
cosmological scales. We study the constraints that cosmic microwave background
measurements set on such large distance modifications of the gravitational
potential.

</DOC>
<DOC>
<DOCNO> 116304 </DOCNO>
Superluminal effects for quantum tunneling through two successive


  We study the phenomenon of one-dimensional non-resonant tunnelling through
two successive potential barriers, separated by an intermediate free region R,
by analyzing the relevant solutions to the Schroedinger equation. We find that
the total traversal time is INDEPENDENT not only of the barrier widths (the
so-called "Hartman effect"), but also of the R-width: so that the effective
velocity in the region R, between the two barriers, can be regarded as
infinite. This agrees with the results known from the corresponding waveguide
experiments, which simulated the tunnelling experiment herein considered
because of the formal identity between the Schroedinger and the Helmholtz
equation [PACS numbers: 73.40.Gk; 03.65.-w; 03.30.+p; 41.20.Jb; 84.40.Az].

</DOC>
<DOC>
<DOCNO> 70453 </DOCNO>
Multivariate Fitting and the Error Matrix in Global Analysis of Data


  When a large body of data from diverse experiments is analyzed using a
theoretical model with many parameters, the standard error matrix method and
the general tools for evaluating errors may become inadequate. We present an
iterative method that significantly improves the reliability of the error
matrix calculation. To obtain even better estimates of the uncertainties on
predictions of physical observables, we also present a Lagrange multiplier
method that explores the entire parameter space and avoids the linear
approximations assumed in conventional error propagation calculations. These
methods are illustrated by an example from the global analysis of parton
distribution functions.

</DOC>
<DOC>
<DOCNO> 12877 </DOCNO>
Fingerprints of spin-fermion pairing in cuprates


  We demonstrate that the feedback effect from bosonic excitations on fermions,
which in the past allowed one to verify the phononic mechanism of a
conventional, $s-$wave superconductivity, may also allow one to experimentally
detect the ``fingerprints'' of the pairing mechanism in cuprates. We argue that
for spin-mediated $d-$wave superconductivity, the fermionic spectral function,
the density of states, the tunneling conductance through an insulating
junction, and the optical conductivity are affected by the interaction with
collective spin excitations, which below $T_c$ are propagating, magnon-like
quasiparticles with gap $\Delta_s$.
 We show that the interaction with a propagating spin excitation gives rise to
singularities at frequencies $\Delta + \Delta_s$ for the spectral function and
the density of states, and at
 $2\Delta + \Delta_s$ for tunneling and optical conductivities, where $\Delta$
is the maximum value of the $d-$wave gap. We further argue that recent optical
measurements also allow one to detect subleading singularities at $4\Delta$ and
$2\Delta + 2\Delta_s$. We consider the experimental detection of these
singularities as a strong evidence in favor of the magnetic scenario for
superconductivity in cuprates.

</DOC>
<DOC>
<DOCNO> 67685 </DOCNO>
Vector Mesons in Medium and Dileptons in Heavy-Ion Collisions


  Theoretical approaches to assess modifications of vector mesons in the
medium, as well as their experimental identification via electromagnetic
probes, are discussed. Implications for the nature of chiral symmetry
restoration in hot/dense matter are outlined and put into context with the
axialvector channel.

</DOC>
<DOC>
<DOCNO> 101870 </DOCNO>
A Survey of Mirror Principle


  This note briefly reviews the {\it Mirror Principle} as developed in the
series of papers \LLYI\LLYII\LLYIII\LLYIV\LCHY. We illustrate this theory with
a few new examples. One of them gives an intriguing connection to a problem of
counting holomorphic disks and annuli. This note has been submitted for the
proceedings of the Workshop on Strings, Duality and Geometry the C.R.M. in
Montreal of March 2000.

</DOC>
<DOC>
<DOCNO> 71194 </DOCNO>
Two-Photon Exclusive Processes in QCD


  Exclusive two-photon reactions such as Compton scattering at large angles,
deeply virtual Compton scattering, and hadron production in photon-photon
collisions provide important tests of QCD at the amplitude level, particularly
as measures of hadron distribution amplitudes and skewed parton distributions.

</DOC>
<DOC>
<DOCNO> 7656 </DOCNO>
Interchain conductivity of coupled Luttinger liquids and organic


  We reconsider the theory of dc and ac interchain conductivity in quasi-one
dimensional systems. Our results are in good agreement with the measured c-axis
optical conductivity of (TMTSF)_2{ClO}_4 and suggest that the c-axis
dc-conductivity of (TMTSF)_2{PF}_6 in the 150K < T < 300Kd$ range is dominated
by precursor effects of Mott localization. The crossover from a Luttinger
liquid at high energy to a Fermi liquid at low energy is also addressed, within
a dynamical mean-field theory. Implications for the inter-chain resistivity and
Drude weight in the Fermi liquid regime are discussed.

</DOC>
<DOC>
<DOCNO> 13834 </DOCNO>
Spin-dependent transport in a Luttinger liquid


  We develop a detailed theory for spin transport in a one-dimensional quantum
wire described by Luttinger liquid theory. A hydrodynamic description for the
quantum wire is supplemented by boundary conditions taking into account the
exchange coupling between the magnetization of ferromagnetic reservoirs and the
boundary magnetization in the wire. Spin-charge separation is shown to imply
drastic and qualitative consequences for spin-dependent transport. In
particular, the spin accumulation effect is quenched except for fine-tuned
parameter regimes. We propose several feasible setups involving an external
magnetic field to detect this phenomenon in transport experiments on
single-wall carbon nanotubes. In addition, electron-electron backscattering
processes, which do not have an important effect on thermodynamic properties or
charge transport, are shown to modify spin-dependent transport through long
quantum wires in a crucial way.

</DOC>
<DOC>
<DOCNO> 69752 </DOCNO>
Initial conditions for hybrid inflation


  In hybrid inflation models, typically only a tiny fraction of possible
initial conditions give rise to successful inflation, even if one assumes
spatial homogeneity. We analyze some possible solutions to this initial
conditions problem, namely assisted hybrid inflation and hybrid inflation on
the brane. While the former is successful in achieving the onset of inflation
for a wide range of initial conditions, it lacks sound physical motivation at
present. On the other hand, in the context of the presently much discussed
brane cosmology, extra friction terms appear in the Friedmann equation which
solve this initial conditions problem in a natural way.

</DOC>
<DOC>
<DOCNO> 12515 </DOCNO>
The Resonance Peak in Sr$_2$RuO$_4$: Signature of Spin Triplet Pairing


  We study the dynamical spin susceptibility, $\chi({\bf q}, \omega)$, in the
normal and superconducting state of Sr$_2$RuO$_4$. In the normal state, we find
a peak in the vicinity of ${\bf Q}_i\simeq (0.72\pi,0.72\pi)$ in agreement with
recent inelastic neutron scattering (INS) experiments. We predict that for spin
triplet pairing in the superconducting state a {\it resonance peak} appears in
the out-of-plane component of $\chi$, but is absent in the in-plane component.
In contrast, no resonance peak is expected for spin singlet pairing.

</DOC>
<DOC>
<DOCNO> 10001 </DOCNO>
Spin dynamics of Mn12-acetate in the thermally-activated tunneling


  In this work, we study the spin dynamics of Mn12-acetate molecules in the
regime of thermally assisted tunneling. In particular, we describe the system
in the presence of a strong transverse magnetic field. Similar to recent
experiments, the relaxation time/rate is found to display a series of
resonances; their Lorentzian shape is found to stem from the tunneling. The
dynamic susceptibility $\chi(w)$ is calculated starting from the microscopic
Hamiltonian and the resonant structure manifests itself also in $\chi(w)$.
Similar to recent results reported on another molecular magnet, Fe8, we find
oscillations of the relaxation rate as a function of the transverse magnetic
field when the field is directed along a hard axis of the molecules. This
phenomenon is attributed to the interference of the geometrical or Berry phase.
We propose susceptibility experiments to be carried out for strong transverse
magnetic fields to study of these oscillations and for a better resolution of
the sharp satellite peaks in the relaxation rates.

</DOC>
<DOC>
<DOCNO> 39980 </DOCNO>
SNO and the neutrino magnetic moment solution of the solar neutrino


  Assuming that the solar neutrino deficit observed in the Homestake, SAGE,
Gallex, Kamiokande and Super-Kamiokande experiments is due to the interaction
of the neutrino transition magnetic moment with the solar magnetic field, we
calculate the expected values of a number of observables to be measured by SNO.
For three model solar magnetic field profiles that produce the best fits of the
previous data we calculate the charged current event rate, the (neutral
current)/(charged current) event ratio and the charged current electron
spectrum as well as its first and second moments. We study the dependence of
the calculated observables on the choice of the magnetic field profile and on
the value of the solar $hep$ neutrino flux. We also compare our results with
those obtained assuming that the solar neutrino problem is due to neutrino
oscillations in vacuum or in matter. We show that there is an overlap or
partial overlap between our predictions and those found for each of the
oscillation solutions (SMA, LMA, LOW and VO). Given the uncertainties in the
calculations and the expected uncertainties in the experimental results, the
unambiguous discrimination between the two types of solutions to the solar
neutrino problem (neutrino oscillations and magnetic moments) on the basis of
the average rates and electron spectrum distortions appears to be difficult.
The possible time dependence of the charged current signal and spectrum
distortion in the case of the magnetic moment solution therefore remains the
best hope for such a discrimination. For a hybrid solution (neutrino magnetic
moment plus flavour mixing) the smoking gun signature would be an observation
of $\bar{\nu}_e$'s from the sun.

</DOC>
<DOC>
<DOCNO> 152451 </DOCNO>
The Symmetry Reduction from Interactions to Particles


  The hypercharge-isospin-color symmetry of the standard model interaction is
drastically reduced to a remaining Abelian electromagnetic $\U(1)$-symmetry for
the particles. It is shown that such a symmetry reduction comes as a
consequence of the central correlation in the internal group as represented by
the standard fields where the hypercharge properties are given by the central
isospin-color properties. A maximal diagonalizable symmetry subgroup (Cartan
torus) of the interaction group for the particles as eigenvectors has to
discard either color (confinement) or isospin. An additional diagonalization
for the external spin properties which come centrally correlated with the
isospin properties enforces the weak isospin breakdown.

</DOC>
<DOC>
<DOCNO> 8369 </DOCNO>
Probing Pseudogap by Josephson Tunneling


  We propose here an experiment aimed to determine whether there are
superconducting pairing fluctuations in the pseudogap regime of the high-$T_c$
materials. In the experimental setup, two samples above $T_c$ are brought into
contact at a single point and the differential AC conductivity in the presence
of a constant applied bias voltage between the samples, $V$, should be
measured. We argue the the pairing fluctuations will produce randomly
fluctuating Josephson current with zero mean, however the current-current
correlator will have a characteristic frequency given by Josephson frequency
$\omega_J = 2 e V /\hbar$. We predict that the differential AC conductivity
should have a peak at the Josephson frequency with the width determined by the
phase fluctuations time.

</DOC>
<DOC>
<DOCNO> 100035 </DOCNO>
Binomial Residues


  A binomial residue is a rational function defined by a hypergeometric
integral whose kernel is singular along binomial divisors. Binomial residues
provide an integral representation for rational solutions of A-hypergeometric
systems of Lawrence type. The space of binomial residues of a given degree,
modulo those which are polynomial in some variable, has dimension equal to the
Euler characteristic of the matroid associated with A.

</DOC>
<DOC>
<DOCNO> 70790 </DOCNO>
Flat Directions in Flipped SU(5) I: All-Order Analysis


  We present a systematic classification of field directions for the
string-derived flipped SU(5) model that are D- and F-flat to all orders.
Properties of the flipped SU(5) model with field values in these directions are
compared to those associated with other flat directions that have been shown to
be F-flat to specific finite orders in the superpotential. We discuss the
phenomenological Higgs spectrum, and quark and charged-lepton mass textures.

</DOC>
<DOC>
<DOCNO> 39696 </DOCNO>
Measurement of Charge Asymmetries in Charmless Hadronic in B Meson


  We search for CP-violating asymmetries (Acp) in the B meson decays to K+-
pi-+, K+- pi0, Ks pi+-, K+- eta', and omega pi+-. Using 9.66 million
Upsilon(4S) decays collected with the CLEO detector, the statistical precision
on Acp is in the range of \pm 0.12 to \pm 0.25 depending on decay mode. While
CP-violating asymmetries of up to \pm 0.5 are possible within the Standard
Model, the measured asymmetries are consistent with zero in all five decay
modes studied.

</DOC>
<DOC>
<DOCNO> 68882 </DOCNO>
Unitarity at small Bjorken x


  This paper presents a solution to the nonlinear small x ``projectile side''
evolution equations as derived by Balitskii in 1996. The solution is based on
functional Fokker-Planck methods. The fixed point at small x is explicitly
calculated and all correlation functions in this limit are determined. They
show clear saturation and unitarization properties. Scaling laws that hold
during the saturation phase and throughout the whole course of the evolution
are established. The corresponding Langevin equations are given as a basis for
numerical simulations opening the field for future studies of dynamical issues
of the evolution not analytically accessible. The methods used may be extended
to the ``target side'' equations of Jalilian-Marian, Kovner, Leonidov and
Weigert.

</DOC>
<DOC>
<DOCNO> 123251 </DOCNO>
Density waves in the shearing sheet I. Swing amplification


  The shearing sheet model of a galactic disk is studied anew. The theoretical
description of its dynamics is based on three building blocks: Stellar orbits,
which are described here in epicyclic approximation, the collisionless
Boltzmann equation determining the distribution function of stars in phase
space, and the Poisson equation in order to take account of the self-gravity of
the disk. Using these tools I develop a new formalism to describe perturbations
of the shearing sheet. Applying this to the unbounded shearing sheet model I
demonstrate again how the disturbances of the disk evolve always into `swing
amplified' density waves, i.e. spiral-arm like, shearing density enhancements,
which grow and decay while the wave crests swing by from leading to trailing
orientation. Several examples are given how such `swing amplification' events
are incited in the shearing sheet.

</DOC>
<DOC>
<DOCNO> 69858 </DOCNO>
U(1) Gauge Field of the Kaluza-Klein Theory in the Presence of Branes


  We investigate the zero mode dimensional reduction of the Kaluza-Klein
unifications in the presence of a single brane in the infinite extra dimension.
We treat the brane as fixed, not a dynamical object, and do not require the
orbifold symmetry. It seems that, contrary to the standard Kaluza-Klein models,
the 4D effective action is no longer invariant under the U(1) gauge
transformations due to the explicit breaking of isometries in the extra
dimension by the brane. Surprisingly, however, the linearized perturbation
analysis around the RS vacuum shows that the Kaluza-Klein gauge field does
possess the U(1) gauge symmetry at the linear level. In addition, the
graviscalar also behaves differently from the 4D point of view. Some physical
implications of our results are also discussed.

</DOC>
<DOC>
<DOCNO> 10806 </DOCNO>
Crossover behavior in He3 and Xe near their liquid-vapor critical point


  We present a detailed discussion of the crossover from mean-field to Ising
critical behavior upon approach of the critical point, both for He3 and Xe. By
combining different sets of experimental data, we are able to cover an
unusually large temperature range on either side of the critical temperature
T_c. Below T_c, we thus can make an accurate comparison with a recent
calculation for the crossover of the coexistence curve. For the regime above
T_c, an analysis of the compressibility demonstrates that the crossover regime
in He3 is unexpectedly widened by a subtle interplay between quantum and
critical fluctuations.

</DOC>
<DOC>
<DOCNO> 122947 </DOCNO>
Theoretical predictions for the cold part of the colliding wind


  We present 2D and 3D hydrodynamical simulations of the colliding wind
interaction zone in WR+O binaries. It is shown that 3D effects can basically
explain certain observed, orbit dependent flux variations. Possible connections
between the interior structure of the interaction zone and dust formation are
outlined and its stability is re-investigated.

</DOC>
<DOC>
<DOCNO> 122084 </DOCNO>
Deprojection Galaxy Cluster X-ray, Sunyaev-Zel'dovich Temperature


  A general method of deprojecting two-dimensional images to reconstruct the
three dimensional structure of the projected object --specifically X-ray,
Sunyaev-Zel'dovich (SZ) and gravitational lensing maps of rich clusters of
galaxies -- assuming axial symmetry (Zaroubi et. al. 98), is considered. Here
we test the applicability of the method for realistic, numerically simulated
galaxy clusters, viewed from three orthogonal projections at four redshift
outputs. We demonstrate that the assumption of axial symmetry is a good
approximation for the 3D structure in this ensemble of galaxy clusters.
Applying the method, we demonstrate that a unique determination of the cluster
inclination angle is possible from comparison between the SZ and X-ray images
and, independently, between SZ and surface density maps. Moreover, the results
from these comparisons are found to be consistent with each other and with the
full 3D structure inclination angle determination. The radial dark matter and
gas density profiles as calculated from the actual and reconstructed 3D
distributions show a very good agreement. The method is also shown to provide a
direct determination of the baryon fraction in clusters, independent of the
cluster inclination angle.

</DOC>
<DOC>
<DOCNO> 178474 </DOCNO>
eta d scattering in the region of the S11 resonance


  We have studied the reaction eta d -> eta d close to threshold within a
nonrelativistic three-body formalism. We considered several eta N and NN
models, in particular potentials with separable form, fitted to the low-energy
eta N and NN data to represent the two-body interactions. We found that with
realistic two-body interactions a quasibound state does not exist in this
system, although there is an enhancement of the cross section by one order of
magnitude, in the region near threshold, which is a genuine three-body effect
not predicted within the impulse approximation.

</DOC>
<DOC>
<DOCNO> 12204 </DOCNO>
Tunneling density of states of high T_c superconductors d-wave BCS model


  Motivated by recent experimental measurements of the tunneling
characteristics of high T_{c} materials using scanning tunneling spectroscopy,
we have calculated the IV and differential conductance curves in the
superconducting state at zero temperature. Comparing the two results obtained
via BCS-like d-wave pairing and the SU(2) slave boson approach, we find that
the slave-boson model can explain the asymmetric background observed in
experiments. The slave-boson model also predicts that the height of the
conductance peak relative to the background is proportional to the hole doping
concentration $x$, at least for under-doped samples. We also observe the
absence of the van Hove singularity, and comment on possible implications.

</DOC>
<DOC>
<DOCNO> 178518 </DOCNO>
Preserving the gauge invariance of meson production currents in the


  A comprehensive formalism is developed to preserve the gauge invariance of
currents describing the photo- or electroproduction of mesons off the nucleon
when the final-state interactions of mesons and nucleons is taken into account
explicitly. Replacing exchange currents by auxiliary currents, it is found that
all contributions due to explicit final-state interactions are purely
transverse and do not contain a Kroll-Ruderman-type contact current. The
relation of the present formulation to tree-level-type prescriptions is shown.

</DOC>
<DOC>
<DOCNO> 69869 </DOCNO>
The ground state of bottomium to two loops and higher


  We consider the properties of the ground state of bottomium. The $\Upsilon$
mass is evaluated to two loops, and including leading higher order
[$O(\alpha_s^5\log\alpha_s)$] and $m_c^2/m_b^2$ corrections. This allows us to
present updated values for the pole mass and $\bar{MS}$ mass of the $b$ quark:
$m_b=5022\pm58$ MeV, for the pole mass, and $\bar{m}_b(\bar{m}_b)=4286\pm36$
MeV for the $\bar{MS}$ one. The value for the \msbar mass is accurate including
and $O(\alpha_s^3)$ corrections and leading orders in the ratio $m_c^2/m_b^2$.
We then consider the wave function for the ground state of $\bar{b}b$, which is
calculated to two loops in the nonrelativistic approximation. Taking into
account the evaluation of the matching coefficients by Beneke and Signer one
can calculate, in principle, the width for the decay $\Upsilon\to e^+e^-$ to
order $\alpha_s^5$. Unfortunately, given the size of the corrections it is
impossible to produce reliable numbers. The situation is slightly better for
the ground state of toponium, where a decay width into $e^+e^-$ of 11 -- 14 keV
is predicted.

</DOC>
<DOC>
<DOCNO> 11861 </DOCNO>
From market games to real-world markets


  This paper uses the development of multi-agent market models to present a
unified approach to the joint questions of how financial market movements may
be simulated, predicted, and hedged against. We examine the effect of different
market clearing mechanisms and show that an out-of-equilibrium clearing process
leads to dynamics that closely resemble real financial movements. We then show
that replacing the `synthetic' price history used by these simulations with
data taken from real financial time-series leads to the remarkable result that
the agents can collectively learn to identify moments in the market where
profit is attainable. We then employ the formalism of Bouchaud and Sornette in
conjunction with agent based models to show that in general risk cannot be
eliminated from trading with these models. We also show that, in the presence
of transaction costs, the risk of option writing is greatly increased. This
risk, and the costs, can however be reduced through the use of a delta-hedging
strategy with modified, time-dependent volatility structure.

</DOC>
<DOC>
<DOCNO> 9423 </DOCNO>
The 1/2-XXZ spin-chain at finite magnetic field: Crossover phenomena


  We investigate the asymptotic behaviour of spin-spin correlation functions
for the integrable Heisenberg chain. To this end we use the Quantum Transfer
Matrix (QTM) technique developed in \cite{AK} which results in a set of
non-linear integral equations (NLIE). In the case of the largest eigenvalue the
solution to these equations yields the free energy and by modifications of the
paths of integration the next-leading eigenvalues and hence the correlation
lengths are obtained. At finite field $h>0$ and sufficiently high temperature
$T$ the next-leading eigenvalue is unique and given by a 1-string solution to
the QTM taking real and negative values thus resulting into exponentially
decaying correlations with antiferromagnetic oscillations. At sufficiently low
temperatures a different behaviour sets in where the next-leading eigenvalues
of QTM are given by a complex conjugate pair of eigenvalues resulting into
incommensurate oscillations.
  The above scenario is the result of analytical and numerical investigations
of the QTM establishing a well defined crossover temperature $T_c(h)$ at which
the 1-string eigenvalue to the QTM gets degenerate with the 2-string solution.
Among other things we find a simple particle-hole picture for the excitations
of the QTM and we make contact with the dressed charge formulation of CFT.

</DOC>
<DOC>
<DOCNO> 120155 </DOCNO>
Optimal Supernova Search Strategies


  Recent use of Type Ia supernovae to measure acceleration of the universe has
motivated questions regarding their optimal use to constrain cosmological
parameters Omega_M, Omega_{\Lambda} and w_Q. In this work we address the
question: what is the optimal distribution of supernovae in redshift in order
to best constrain the cosmological parameters? The solution to this problem is
not only of theoretical interest, but can be useful in planning supernova
searches. Using the Fisher matrix formalism we show that the error ellipsoid
corresponding to N parameters (for N=1, 2, 3) has the smallest volume if the
supernovae are located at N discrete redshifts, with equal number of supernovae
at each redshift and with one redshift always being the maximum one probed.
Including marginalization over the ``nuisance parameter'' M changes this result
only trivially.

</DOC>
<DOC>
<DOCNO> 100777 </DOCNO>
Conformal covariance of massless free nets


  In the present paper we review in a fibre bundle context the covariant and
massless canonical representations of the Poincare' group as well as certain
unitary representations of the conformal group (in 4 dimensions). We give a
simplified proof of the well-known fact that massless canonical representations
with discrete helicity extend to unitary and irreducible representations of the
conformal group mentioned before. Further we give a simple new proof that
massless free nets for any helicity value are covariant under the conformal
group. Free nets are the result of a direct (i.e. independent of any explicit
use of quantum fields) and natural way of constructing nets of abstract
C*-algebras indexed by open and bounded regions in Minkowski space that satisfy
standard axioms of local quantum physics. We also give a group theoretical
interpretation of the embedding ${\got I}$ that completely characterizes the
free net: it reduces the (algebraically) reducible covariant representation in
terms of the unitary canonical ones. Finally, as a consequence of the conformal
covariance we also mention for these models some of the expected algebraic
properties that are a direct consequence of the conformal covariance (essential
duality, PCT--symmetry etc.).

</DOC>
<DOC>
<DOCNO> 80896 </DOCNO>
Theories with global gauge anomalies on the lattice


  A global anomaly in a chiral gauge theory manifests itself in different ways
in the continuum and on the lattice. In the continuum case, functional
integration of the fermion determinant over the whole space of gauge fields
yields zero. In the case of the lattice, it is not even possible to define a
fermion measure over the whole space of gauge configurations. However, this is
not necessary, and as in the continuum, a reduced functional integral is
sufficient for the existence of the theory.

</DOC>
<DOC>
<DOCNO> 100051 </DOCNO>
Non-unitary set-theoretical solutions to the Quantum Yang-Baxter


  We develop a theory of non-unitary set-theoretical solutions to the Quantum
Yang-Baxter equation. Our results generalize those obtained by Etingof,
Schedler and the author. We remark that some of our constructions are similar
to constructions obtained by Lu, Yan and Zhu.

</DOC>
<DOC>
<DOCNO> 11656 </DOCNO>
Conductance fluctuations in a quantum dot under almost periodic ac


  It is shown that the variance of the linear dc conductance fluctuations in an
open quantum dot under a high-frequency ac pumping depends significantly on the
spectral content of the ac field. For a sufficiently strong ac field
$\gamma\tau_{\phi}<< 1$, where $1/\tau_{\phi}$ is the dephasing rate induced by
ac noise and $\gamma$ is the electron escape rate, the dc conductance
fluctuations are much stronger for the harmonic pumping than in the case of the
noise ac field of the same intensity. The reduction factor $r$ in a static
magnetic field takes the universal value of 2 only for the white--noise
pumping. For the strictly harmonic pumping $A(t)=A_{0}\cos\omega t$ of
sufficiently large intensity the variance is almost insensitive to the static
magnetic field $r-1= 2\sqrt{\tau_{\phi}\gamma} << 1$. For the quasi-periodic ac
field of the form $A(t)=A_{0} [\cos(\omega_{1} t)+\cos(\omega_{2} t)]$ with
$\omega_{1,2} >> \gamma$ and $\gamma\tau_{\phi} << 1$ we predict the novel
effect of enchancement of conductance fluctuations at commensurate frequencies
$\omega_{2}/\omega_{1}=P/Q$.

</DOC>
<DOC>
<DOCNO> 120457 </DOCNO>
Good Views of the Galaxy


  Fitting Galactic structure models to star counts only provides useful
information about the Galaxy in some directions. In this paper, we investigate
the use of $\chi^2$ goodness-of-fit tests to discriminate between degenerate
Galactic structure models, and the implications of this technique for the
Galactic spheroid and thick disk components. The axis ratio of the Galactic
spheroid and the normalization of spheroid stars with respect to disk stars
introduce a degenerate effect which means that Galactic structure models with
certain combinations of these parameters are indistinguishable from each other
in most directions. We present an analysis of the optimal directions in which
these degeneracies can be lifted. Poisson and magnitude errors are taken into
account, and an attempt is made to place an upper limit on the systematic error
due to separation of spheroid stars from thick/old disk stars. We find that the
magnitude range $20 < V < 21$ is the best for lifting most degeneracies, and
present the optimal combinations of directions using which this can be
achieved. We also give directions in which the signature of the presence of a
Galactic thick disk can be most readily identified, and the directions in which
contamination from a thick disk can be minimized. It is hoped that forthcoming
data from large-scale sky surveys would reveal much about the structure of our
Galaxy using star count techniques.

</DOC>
<DOC>
<DOCNO> 13863 </DOCNO>
Strain Relaxation Mechanisms and Local Structural Changes in


  In this work, we address issues pertinent to the understanding of the
structural and electronic properties of Si_{1-x} Ge_{x}alloys, namely, (i) how
does the lattice constant mismatch between bulk Si and bulk Ge manifests itself
in the alloy system? and (ii) what are the relevant strain release mechanisms?
To provide answers to these questions, we have carried out an in-depth study of
the changes in the local geometric and electronic structures arising from the
strain relaxation in Si_{1-x} Ge_{x} alloys using an ab initio molecular
dynamics scheme. The optimized lattice constant, while exhibiting a general
trend of linear dependence on the composition (Vegard's law), shows a negative
deviation from Vegard's law in the vicinity of x=0.5. We delineate the
mechanisms responsible for each one of the above features. We show that the
radial-strain relaxation through bond stretching is responsible for the overall
trend of linear dependence of the lattice constant on the composition. On the
other hand, the negative deviation from Vegard's law is shown to arise from the
angular-strain relaxation.

</DOC>
<DOC>
<DOCNO> 150765 </DOCNO>
On the relationship of gravitational constants in KK reduction


  In this short note, we try to clarify a seemly trivial but often confusing
question in relating a higher-dimensional physical gravitational constant to
its lower-dimensional correspondence in Kaluza-Klein reduction. In particular,
we re-derive the low-energy M-theory gravitational constant in terms of type
IIA string coupling $g_s$ and constant $\alpha'$ through the metric relation
between the two theories.

</DOC>
<DOC>
<DOCNO> 99712 </DOCNO>
Complete hyperbolic neighborhoods in almost-complex surfaces


  We prove that each point in an almost-complex surface has a basis of complete
hyperbolic neighborhoods. The problem is local, and therefore we can consider
the case when our surface is ${\bf R^4}$ with an arbitrary almost-complex
structure $J$ of class $C^{1.\alpha}$. Let $C$ be a non-singular $J$-complex
curve passing through the origin. Our result cah be stated as follows: There
exists a basis $\{U_j\}$ of neighborhoods of zero in ${\bf R^4}$, such that
$(U_j,J)$ are complete hyperbolic in the sence of Kobayashi, moreover
$(U_j\setminus C,J)$ are complete hyperbolic as well.
  The fact that this result remains true for any almost-complex structure is
somewhat suprising. Really, given any germ of a non-singular real surface $C\ni
0$ in ${\bf R^4}$, one can easily construct an almost-complex structure $J$ in
a neighborhood of zero, such that $C$ becomes a $J$-complex curve.
  Typical corollary is the following:
  Let ${\cal M}_{\omega, 5l}$ be the Banach manifold consisting of pairs
$(J,\{D_j\}_{j=1}^5)$, where $J$ is any almost-complex structure on ${\bf
CP^2}$ tamed by the Fubini-Studi form $\omega$ and $\{D_j\}_{j=1}^5$ the union
of five $J$-complex lines in ${\bf CP^2}$ in general position. The set ${\cal
H}_{\omega, 5l}$ consisting of $(J, \{D_j\}_{j=1}^5)$ with $Y=({\bf
CP^2}\setminus \bigcup_{j=1}^5 D_j,J)$ hyperbolically imbedded into $({\bf
CP^2}, J)$ is an open nonempty subset of ${\cal M}{\omega, 5l}$.

</DOC>
<DOC>
<DOCNO> 100809 </DOCNO>
Sharp L1 Stability Estimates for Hyperbolic Conservation Laws


  In this paper, we introduce a generalization of Liu-Yang's weighted norm to
linear and to nonlinear hyperbolic equations. Extending a result by Hu and
LeFloch for piecewise constant solutions, we establish sharp L1 continuous
dependence estimates for general solutions of bounded variation. Two different
strategies are successfully investigated. On one hand, we justify passing to
the limit in an $L^1$ estimate valid for piecewise constant wave-front tracking
approximations. On the other hand, we use the technique of generalized
characteristics and, following closely an approach by Dafermos, we derive the
sharp L1 estimate directly from the equation.

</DOC>
<DOC>
<DOCNO> 40422 </DOCNO>
An improved direct measurement of leptonic coupling asymmetries with


  We present final measurements of the Z boson-lepton coupling asymmetry
parameters Ae, Amu, and Atau with the complete sample of polarized Z bosons
collected by the SLD detector at the SLAC Linear Collider. From the left-right
production and decay polar angle asymmetries in leptonic Z decays we measure Ae
= 0.1544 +- 0.0060, Amu = 0.142 +- 0.015, and Atau = 0.136 +- 0.015. Combined
with our left-right asymmetry measured from hadronic decays, we find Ae =
0.1516 +- 0.0021. Assuming lepton universality, we obtain a combined effective
weak mixing angle of sin**2 theta^{eff}_W = 0.23098 +- 0.00026.

</DOC>
<DOC>
<DOCNO> 102132 </DOCNO>
Cohomological properties of ruled symplectic structures


  This survey presents some recent results by the authors and Polterovich on
the topological properties of ruled symplectic manifolds. The bundle M \to P
\to B that is associated with a ruled manifold has the group of Hamiltonian
symplectomorphisms of M as structure group if the base is simply connected.
Thus information about Hamiltonian bundles gives stability results for ruled
structures as well as obstructions to their existence.

</DOC>
<DOC>
<DOCNO> 9760 </DOCNO>
Trace and antitrace maps for aperiodic sequences, their extensions and


  We study aperiodic systems based on substitution rules by means of a
transfer-matrix approach. In addition to the well-known trace map, we
investigate the so-called `antitrace' map, which is the corresponding map for
the difference of the off-diagonal elements of the 2x2 transfer matrix. The
antitrace maps are obtained for various binary, ternary and quaternary
aperiodic sequences, such as the Fibonacci, Thue-Morse, period-doubling,
Rudin-Shapiro sequences, and certain generalizations. For arbitrary
substitution rules, we show that not only trace maps, but also antitrace maps
exist. The dimension of the our antitrace map is r(r+1)/2, where r denotes the
number of basic letters in the aperiodic sequence. Analogous maps for specific
matrix elements of the transfer matrix can also be constructed, but the maps
for the off-diagonal elements and for the difference of the diagonal elements
coincide with the antitrace map. Thus, from the trace and antitrace map, we can
determine any physical quantity related to the global transfer matrix of the
system. As examples, we employ these dynamical maps to compute the transmission
coefficients for optical multilayers, harmonic chains, and electronic systems.

</DOC>
<DOC>
<DOCNO> 152195 </DOCNO>
Scaling Behavior of Black Hole Entropy


  It is shown that the entropy of fourdimensional black holes in string theory
compactified on weighted Calabi-Yau hypersurfaces shows scaling behavior in a
certain limit. This leads to non-monotonic functions on the moduli space.

</DOC>
<DOC>
<DOCNO> 121552 </DOCNO>
A grid of composite models for the simulation of the emission-line


  A grid of composite models for the narrow line region of active galaxies,
which consistently account for both the effect of a photoionizing radiation
from the active center and of a shock front, is presented. Theoretical results,
calculated with the SUMA code, are given for different values of shock
velocities, preshock densities, geometrical thickness of the clouds, and,
particularly, for the ionizing radiation intensity in a large range. The input
parameters are chosen within the ranges indicated by previous fits of several
observed emission-line and continuum spectra from active galaxies. Shock
velocities from 100 \kms ~to 1500 \kms ~and preshock densities from 100 \cm3 to
1000 \cm3 are considered. The line intensities of the most important
ultraviolet, optical and infrared transitions are obtained and are listed in
several tables.

</DOC>
<DOC>
<DOCNO> 84162 </DOCNO>
Monopoles and Dyons in the Pure Einstein-Yang-Mills Theory


  In the pure Einstein-Yang-Mills theory in four dimensions there exist
monopole and dyon solutions. The spectrum of the solutions is discrete in
asymptotically flat or de Sitter space, whereas it is continuous in
asymptotically anti-de Sitter space. The solutions are regular everywhere and
specified with their mass, and non-Abelian electric and magnetic charges. In
asymptotically anti-de Sitter space a class of monopole solutions have no node
in non-Abelian magnetic fields, and are stable against spherically symmetric
perturbations.

</DOC>
<DOC>
<DOCNO> 11348 </DOCNO>
First principles study of strain/electronic interplay in ZnO; Stress and


  We present a first-principles study of the relationship between stress,
temperature and electronic properties in piezoelectric ZnO. Our method is a
plane wave pseudopotential implementation of density functional theory and
density functional linear response within the local density approximation. We
observe marked changes in the piezoelectric and dielectric constants when the
material is distorted. This stress dependence is the result of strong, bond
length dependent, hybridization between the O $2p$ and Zn $3d$ electrons. Our
results indicate that fine tuning of the piezoelectric properties for specific
device applications can be achieved by control of the ZnO lattice constant, for
example by epitaxial growth on an appropriate substrate.

</DOC>
<DOC>
<DOCNO> 150413 </DOCNO>
Hidden local, quasi-local and non-local Symmetries in Integrable Systems


  The knowledge of {\it non usual} and sometimes {\it hidden} symmetries of
(classical) integrable systems provides a very powerful setting-out of
solutions of these models. Primarily, the understanding and possibly the
quantisation of intriguing symmetries could give rise to deeper insight into
the nature of field spectrum and correlation functions in quantum integrable
models. With this perspective in mind we will propose a general framework for
discovery and investigation of local, quasi-local and non-local symmetries in
classical integrable systems. We will pay particular attention to the structure
of symmetry algebra and to the r\^ole of conserved quantities. We will also
stress a nice unifying point of view about KdV hierarchies and Toda field
theories with the result of obtaining a Virasoro algebra as exact symmetry of
Sine-Gordon Model.

</DOC>
<DOC>
<DOCNO> 13548 </DOCNO>
Electron-hole correlations in semiconductor quantum dots with


  The electron-hole states of semiconductor quantum dots are investigated
within the framework of empirical tight-binding descriptions for Si, as an
example of an indirect gap material, and InAs and CdSe as examples of typical
III-V and II-VI direct-gap materials. The electron-hole Coulomb interaction is
largely insensitive to both the real-space description of the atomic basis
orbitals and different ways of optimizing the tight-binding parameters.
Tight-binding parameters that are optimized to give the best effective masses
significantly improve the energies of the excitonic states due to the better
single-particle energies. However, the Coulomb interaction does not vary much
between different parameterizations. In addition, the sensitivity of the
Coulomb interaction to the choice of atomic or bitals decreases with increasing
dot size. Quantitatively, tight-binding treatments of correlation effects are
reliable for dots with radii larger than 15--20 angstrom. The calculated
excitonic gaps are in good agreement with recent photoluminescence data for Si
and CdSe but agree less well for InAs. Further, the effective range of the
electron-hole exchange interaction is investigated in detail. In quantum dots
of the direct-gap materials InAs and CdSe, the exchange interaction can be
long-ranged, extending over the whole dot when there is no local (onsite)
orthogonality between the electron and hole wave functions. By contrast, for Si
quantum dots the extra phase factor due to the indirect gap effectively limits
the range to about 15 angstrom, independent of the dot size.

</DOC>
<DOC>
<DOCNO> 121125 </DOCNO>
Blue Quasars and Blazar Unification Schemes


  Blue quasars (BQs) are sources with strong broad emission lines and flat hard
X-ray spectra, properties that resemble classical flat spectrum radio quasars
(FSRQs), and high peak frequencies and steep soft X-ray spectra, properties
that resemble intermediate or high peak frequency BL Lacertae objects(IBLs and
HBLs respectively).
  BQs challenge our understanding of blazar properties in terms of a luminosity
sequence, which makes their incorporation into current blazar unification
schemes problematic. In this work we show that this situation can be remedied
if, in addition to the intrinsic luminosity, the orientation of the blazar jet
is explicitly considered. We show, using published data, that the recently
studied BQs are relatively misaligned blazars, and we examine the predicted
aligned population. We examine both possible cases, sources with pure
synchrotron spectra and sources with an optical--UV thermal contribution, for
both constant velocity and accelerating jets. We show that the aligned sources
are similar to FSRQs, and we suggest ways to distinguish between constant
velocity and accelerating flows. We point out that IBLs are more aligned and
less powerful than BQs and we address the very different emission line
properties of these sources which display similar spectral energy
distributions.

</DOC>
<DOC>
<DOCNO> 118761 </DOCNO>
BeppoSAX observation of the transient X-ray pulsar GS 1843+00


  We present the results from both the timing and spectroscopic analysis of the
transient X-ray pulsar GS 1843+00 observed by the BeppoSAX satellite on 1997
April 4, when the source was at a luminosity of ~10^{37} erg s^{-1}. GS 1843+00
shows a very hard spectrum that is well fitted by an absorbed power law (N_H
\~2.3 10^{22} cm^{-2}) modified by a high energy cut-off above 6 keV. The source
shows a small pulse amplitude in the whole energy band. The pulse profile
evolves with energy from a double-peaked to single-peaked shape. The
barycentric pulse period is 29.477+/-0.001 s.

</DOC>
<DOC>
<DOCNO> 70444 </DOCNO>
The seesaw mechanism at arbitrary order: disentangling the small scale


  We develop a recipe which allows one to recursively and uniquely decouple the
large scale from the small scale in mass matrices of the seesaw type, up to any
order in the inverse of the large scale. Our method allows one to calculate the
mass matrix of the light neutrinos with arbitrary precision. The same method
can be applied in the case of quark mass matrices in an extension of the
Standard Model with vector-like quarks which have mass terms at a scale much
higher than the electroweak scale.

</DOC>
<DOC>
<DOCNO> 121014 </DOCNO>
Study of the Temporal Behavior of 4U 1728-34 as a Function of its


  We study the timing properties of the bursting atoll source 4U 1728-34 as a
function of its position in the X-ray color-color diagram. In the island part
of the color-color diagram (corresponding to the hardest energy spectra) the
power spectrum of 4U 1728-34 shows several features such as a band-limited
noise component present up to a few tens of Hz, a low frequency quasi-periodic
oscillation (LFQPO) at frequencies between 20 and 40 Hz, a peaked noise
component around 100 Hz, and one or two QPOs at kHz frequencies. In addition to
these, in the lower banana (corresponding to softer energy spectra) we also
find a very low frequency noise (VLFN) component below ~1 Hz. In the upper
banana (corresponding to the softest energy spectra) the power spectra are
dominated by the VLFN, with a peaked noise component around 20 Hz. We find that
the frequencies of the kHz QPOs are well correlated with the position in the
X-ray color-color diagram. For the frequency of the LFQPO and the break
frequency of the broad-band noise component the relation appears more complex.
These frequencies both increase when the frequency of the upper kHz QPO
increases from 400 to 900 Hz, but at this frequency a jump in the values of the
parameters occurs. We interpret this jump in terms of the gradual appearance of
a QPO at the position of the break at high inferred mass accretion rate, while
the previous LFQPO disappears. Simultaneously, another kind of noise appears
with a break frequency of ~7 Hz, similar to the NBO of Z sources. The 100 Hz
peaked noise does not seem to correlate with the position of the source in the
color-color diagram, but remains relatively constant in frequency. This
component may be similar to several 100 Hz QPOs observed in black hole
binaries.

</DOC>
<DOC>
<DOCNO> 101110 </DOCNO>
Weighing operator perturbation from quasi-critical source system


  In Hilbert space, a linear source-to-flux problem in the critical (zero
eigenvalue) limit is ill-posed, but regularized by a constraint on a linear
functional, fulfilled by tuning some control variable. For any exciting
perturbation, I obtain, by spectral decomposition and perturbation theory, the
regularized flux and the regularizing control variable non-linear responses.
May the exciting perturbation be obtained, inversely, from observable
responses? Yes, in some cases, from the existence of a weight scale, a
perturbation series, determined by recursion relations, involving well-posed
source problems, and the possibility of obtaining this weight scale from
observables of both the unconstrained and constrained systems.

</DOC>
<DOC>
<DOCNO> 170590 </DOCNO>
Entanglement of coherent states and decoherence


  A possibility to produce entangled superpositions of strong coherent states
is discussed. A recent proposal by Howell and Yazell [Phys. Rev. A 62, 012102
(2000)] of a device which entangles two strong coherent coherent states is
critically examined. A serious flaw in their design is found. New modified
scheme is proposed and it is shown that it really can generate non-classical
states that can violate Bell inequality. Moreover, a profound analysis of the
effect of losses and decoherence on the degree of entanglement is accomplished.
It reveals the high sensitivity of the device to any disturbances and the
fragility of generated states.

</DOC>
<DOC>
<DOCNO> 11847 </DOCNO>
Precursory Metal-Insulator transition in a small cluster of the `t-J'


  We study the effect of hole hopping in a doped antiferromagnet described by
the `t-J' model, using exact analytic solutions for small clusters. In spite of
the small size, they reveal interesting details about the magnetic order, which
are not apparent in Mean Field treatments or in numerical calculations. The
4-site cluster with one hole yields the most interesting physics, displaying
different behaviors for the ground state: i) an antiferromagnetic phase for
t<<J, where the hole seems to be localized, not affecting the order of the
Heisenberg spins; ii)another regime for t~J that presents mixed ferro and
antiferro correlations and coexistence of metallic and insulating behaviors,
with the presence of charge and spin density waves, in what may be the analog
of the spiral phase obtained in Mean Field solutions; and finally iii)for t>>J,
we obtain strong ferromagnetic correlations (maximum spin) and no density
waves, with quantum fluctuations precluding the saturation of the magnetic
moment. This behavior shows traces of a metal-insulator transition as the hole
kinetic energy competes with the antiferromagnetic interactions.

</DOC>
<DOC>
<DOCNO> 116508 </DOCNO>
Optimal Mutation Rates in Dynamic Environments


  In this paper we study the evolution of the mutation rate for simple
organisms in dynamic environments. A model with multiple fitness coding loci
tracking a moving fitness peak is developed and an analytical expression for
the optimal mutation rate is derived. Surprisingly it turns out that the
optimal mutation rate per genome is approximately independent of genome length,
something that also has been observed in nature. Simulations confirm the
theoretical predictions. We also suggest an explanation for the difference in
mutation frequency between RNA and DNA based organisms.

</DOC>
<DOC>
<DOCNO> 39711 </DOCNO>
Three-body Supersymmetric Top Decays


  We discuss three-body supersymmetric top decays, in schemes both with and
without R-parity conservation, assuming that sfermion masses are larger than
m_t. We find that MSSM top decays into chargino/neutralino pairs have a strong
kinematic suppression in the region of the supersymmetric parameter space
consistent with the LEP limits, with a decay width =< 10^{-5} GeV. MSSM top
decays into neutralino pairs have less kinematical suppression, but require a
flavour-changing vertex, and are likely to have a smaller rate. On the other
hand, R-violating decays to single charginos, neutralinos and conventional
fermions can be larger for values of the R-violating couplings still permitted
by other upper limits. The cascade decays of the charginos and neutralinos may
lead to spectacular signals with explicit lepton-number violation, such as
like-sign lepton events.

</DOC>
<DOC>
<DOCNO> 151295 </DOCNO>
1+1 Dimensional NCOS and its U(N) Gauge Theory Dual


  We study some aspects of open string theories on D-branes with critical
electric fields. We show that the massless open string modes that move in the
direction of the electric field decouple. In the 1+1 dimensional case the dual
theory is U(N) SYM with electric flux, and the decoupling of massless open
strings is dual to the decoupling of the U(1) degrees of freedom. We also show
that, if the direction along the electric field is compact, then there are
finite energy winding closed string modes. They are dual to Higgs branch
excitations of the SYM theory, and their energetics works accordingly. These
properties provide new non-trivial evidence for the duality.

</DOC>
<DOC>
<DOCNO> 174448 </DOCNO>
Nuclear multifragmentation, percolation and the Fisher Droplet Model:


  It is shown that the Fisher Droplet Model (FDM), percolation and nuclear
multifragmentation share the common features of reducibility (stochasticity in
multiplicity distributions) and thermal scaling (one-fragment production
probabilities are Boltzmann factors). Barriers obtained, for cluster production
on percolation lattices, from the Boltzmann factors show a power-law dependence
on cluster size with an exponent of 0.42 +- 0.02. The EOS Au multifragmentation
data yield barriers with a power-law exponent of 0.68 +- 0.03. Values of the
surface energy coefficient of a low density nuclear system are also extracted.

</DOC>
<DOC>
<DOCNO> 121130 </DOCNO>
Diffraction-limited near-IR imaging at Keck reveals asymmetric,


  We present multi-epoch, diffraction-limited images of the nebula around the
carbon star CIT 6 at 2.2 microns and 3.1 microns from aperture masking on the
Keck-I telescope. The near-IR nebula is resolved into two main components, an
elongated, bright feature showing time-variable asymmetry and a fainter
component about 60 milliarcseconds away with a cooler color temperature. These
images were precisely registered (~35 milliarcseconds) with respect to recent
visible images from the Hubble Space Telescope (Trammell et al. 2000), which
showed a bipolar structure in scattered light. The dominant near-IR feature is
associated with the northern lobe of this scattering nebula, and the
multi-wavelength dataset can be understood in terms of a bipolar dust shell
around CIT 6. Variability of the near-IR morphology is qualitatively consistent
with previously observed changes in red polarization, caused by varying
illumination geometry due to non-uniform dust production. The blue emission
morphology and polarization properties can not be explained by the above model
alone, but require the presence of a wide binary companion in the vicinity of
the southern polar lobe. The physical mechanisms responsible for the breaking
of spherical symmetry around extreme carbon stars, such as CIT 6 and IRC+10216,
remain uncertain.

</DOC>
<DOC>
<DOCNO> 40343 </DOCNO>
Direct measurement of the pion valence quark momentum distribution, the


  We present the first direct measurements of the pion valence quark momentum
distribution which is related to the square of the pion light-cone wave
function. The measurements were carried out using data on diffractive
dissociation of 500 GeV/c $\pi^-$ into di-jets from a platinum target at
Fermilab experiment E791. The results show that the $|q\bar {q}>$ light-cone
asymptotic wave function, which was developed using perturbative QCD methods,
describes the data well for $Q^2 \sim 10 ~{\rm (GeV/c)^2}$ or more. We also
measured the transverse momentum distribution of the diffractive di-jets.

</DOC>
<DOC>
<DOCNO> 122236 </DOCNO>
Advances in s-process models


  Within the framework of the current models for the slow neutron capture (s)
process in Asymptotic Giant Branch (AGB) stars we explore the uncertainties
introduced by the assumptions made on stellar modeling. On the basis of star
models constructed with three different evolutionary codes we generate detailed
neutron-capture nucleosynthesis post-processing models. The main difference
among the codes is that one of them includes an overshooting mechanism. As a
result, the neutron fluxes are stronger both during the interpulse periods and
within thermal pulses. The efficiency of the C13 source is also studied and we
find that a linear relationship exists between the initial C12 in the
intershell and the maximum number of neutrons produced.

</DOC>
<DOC>
<DOCNO> 10720 </DOCNO>
Stretched exponential relaxation in the Coulomb glass


  The relaxation of the specific heat and the entropy to their equilibrium
values is investigated numerically for the three-dimensional Coulomb glass at
very low temperatures. The long time relaxation follows a stretched exponential
function, $f(t)=f_0\exp[-(t/\tau)^\beta]$, with the exponent $\beta$ increasing
with the temperature. The relaxation time follows an Arrhenius behavior
divergence when $T\to 0$. A relation between the specific heat and the entropy
in the long time regime is found.

</DOC>
<DOC>
<DOCNO> 7714 </DOCNO>
Potential Energy in a Three-Dimensional Vibrated Granular Medium


  Fast NMR imaging was used to measure the density profile of a
three-dimensional granular medium fluidized by vertical vibrations of the
container. For container acceleration much larger than gravity, the rise in
center of mass of the granular medium is found to scale as (v0^alpha)/(N^beta)
with alpha = 1.0 +/-0.2 and beta = 0.5 +/- 0.1, where v0 is the vibration
velocity and N is the number of grains in the container. This value for alpha
is significantly less than found previously for experiments and simulations in
one dimension (alpha = 2) and two dimensions (alpha = 1.3-1.5).

</DOC>
<DOC>
<DOCNO> 152095 </DOCNO>
Asymptotically Anti-de Sitter spacetimes and their stress energy tensor


  We consider asymtotically anti-de Sitter spacetimes in general dimensions. We
review the origin of infrared divergences in the on-shell gravitational action,
and the construction of the renormalized on-shell action by the addition of
boundary counterterms. In odd dimensions, the renormalized on-shell action is
not invariant under bulk diffeomorphisms that yield conformal transformations
in the boundary (holographic Weyl anomaly). We obtain formulae for the
gravitational stress energy tensor, defined as the metric variation of the
renormalized on-shell action, in terms of coefficients in the asymptotic
expansion of the metric near infinity. The stress energy tensor transforms
anomalously under bulk diffeomorphisms broken by infrared divergences.

</DOC>
<DOC>
<DOCNO> 100398 </DOCNO>
Cobordisms and Reidemeister torsions of homotopy lens spaces


  We show that any 3-dimensional homotopy lens space M^3 that is
simple-homotopy equivalent to a lens space L(p,q) is topologically s-cobordant
to the lens space. It follows that M has the same multi-signature as L(p,q) and
the action of \pi_1(M) on the universal cover of M embeds in an orthogonal
action on S^7.

</DOC>
<DOC>
<DOCNO> 68770 </DOCNO>
On Stability of the Three 3-brane Model


  We show that the Goldberger-Wise mechanism for the three 3-brane scenario
proposed by Kogan et al. stabilizes the radion. We find that the system of
3-branes stabilizes in such a way that the loss in the scale factor is
insignificant. That is, the negative tension brane chooses to stay close to the
visible brane.

</DOC>
<DOC>
<DOCNO> 11210 </DOCNO>
Non-Langevin behaviour of the uncompensated magnetisation in


  The magnetic behaviour of nanoparticles of antiferromagnetic ferritin has
been investigated by 57Fe Mossbauer absorption spectroscopy and magnetisation
measurements, in the temperature range 2.5K-250K and with magnetic fields up to
7T. Samples containing nanoparticles with an average number of Fe atoms ranging
from 400 to 2500 were studied. The value of the anisotropy energy per unit
volume was determined and found to be in the range 3-6 10**5 ergs/cm3, which is
a value typical for ferric oxides. By comparing the results of the two
experimental methods at large field, we show that, contratry to what is
currently assumed, the uncompensated magnetisation of the feritin cores in the
superparamagnetic regime does not follow a Langevin law. For magnetic fields
below the spin-flop field, we propose an approximate law for the field and
temperature variation of the uncompensated magnetisation which has so far never
been applied in antiferromagnetic systems. This approach should more generally
hold for randomly oriented antiferro- magnetic nanoparticles systems with weak
uncompensated moments.

</DOC>
<DOC>
<DOCNO> 117643 </DOCNO>
The Diffusive Galactic GeV/TeV Gamma-Ray Background: Sources vs.


  The diffuse Galactic gamma-ray background, as observed with EGRET on CGRO,
exceeds the model predictions significantly above 1 GeV. This is particularly
true for the inner Galaxy. We shall discuss here the contribution of the
Galactic Cosmic Ray (GCR) sources, considered as unresolved, and in addition
the possibility that the transport of the GCRs out of the Galaxy is not uniform
over the Galactic disk. In both cases the spectrum of the diffuse gamma-rays is
harder than the GCR spectrum in the neighborhood of the Solar system, as
observed in situ. The source contribution is a necessary and, as it turns out,
significant part of the diffuse background, whereas the transport effect is one
of several conceivable additional causes for the hard diffuse gamma-ray
spectrum observed.

</DOC>
<DOC>
<DOCNO> 68845 </DOCNO>
Variable number schemes for heavy quark electroproduction


  We compare variable number schemes for heavy quark electroproduction

</DOC>
<DOC>
<DOCNO> 70830 </DOCNO>
The topological susceptibility and pion decay constant from lattice QCD


  We study the topological susceptibility, chi, in two flavour lattice QCD. We
find clear evidence for the expected suppression of chi at small quark mass.
The estimate of the pion decay constant, f_pi = 105 +/-5 +18/-10 MeV, is
consistent with the experimental value of approximately 93 MeV. We compare chi
to the large-N_c prediction and find consistency over a large range of quark
masses.

</DOC>
<DOC>
<DOCNO> 121624 </DOCNO>
Broad band spectrum of Cygnus X-1 in two spectral states with BeppoSAX


  We report on the 0.5--200 keV spectral properties of Cyg X-1 observed at
different epochs with the Narrow Field Instruments of the BeppoSAX satellite.
The source was in its soft state during the first observation of 1996 June. In
the second observation of 1996 September, the source had parameters
characteristic to its hard state. A soft X-ray excess, a broad Fe K$\alpha$
line and Compton reflection are clearly detected in both states. The soft-state
broad-band continuum is well modeled by a disk blackbody (accounting for the
soft excess) and Compton upscattering of the disk photons by a hybrid,
thermal/non-thermal, plasma, probably forming a corona above the disk (also
giving rise to the Compton-reflection component). In the hard state, the
primary hard X-ray spectrum can be well modeled by Compton upscattering of a
weak blackbody emission by a thermal plasma at a temperature of $\sim 60$ keV.
The soft excess is then explained by thermal Comptonization of the same
blackbody emission by another hot plasma cloud characterized by a low value of
its Compton parameter. Finally, we find the characteristic ratio of the
bolometric flux in the soft state to that in the hard state to be about 3. This
value is much more compatible with theories of state transitions than the
previously reported (and likely underestimated) value of 1.5.

</DOC>
<DOC>
<DOCNO> 169675 </DOCNO>
Physical model of Dirac electron. Calculation of its mass at rest and


  The physical model (PhsMdl) of the relativistic quantized Dirac's electron
(DrEl) is proposed. The DrEl is regarded as a point-like (PntLk) elementary
electric charge (ElmElcChrg), taking simultaneously part in following four
disconnected different motions: a/ in Einstein's random trembling harmonic
shudders as a result of momentum recoils (impulse kicks), forcing the DrEl's
PntLk ElmElcChrg at its continuous emission and absorption of high energy
stochastic virtual photons (StchVrtPhtns) by its PntLk ElmElcChrg ; b/ in
Schrodinger's fermion vortical harmonic oscillations of DrEl's fine spread
(FnSpr) ElmElcChrg, who minimizes the self-energy at a rest of is an
electromagnetic self-action between its continuously moving FnSpr ElmElcChrg
and proper magnetic dipole moment (MgnDplMmn) and the corresponding potential
and vector-potential; All the relativistic dynamical properties of the DrEl are
results of the participate of its FnSpr ElmElcChrg in the Schrodinger's fermion
vortical harmonic oscillations. c/ in Furthian quantized stochastic boson
circular harmonic oscillations as a result of the permanent electric or
magnetic interaction of its well spread (WllSpr) ElmElcChrg or proper MgnDplMmn
with the electric intensity (ElcInt) or the magnetic intensity (MgnInt) of the
resultant quantized electromagnetic field (QntElcMgnFld) of all the
StchVrtPhtns within the fluctuating vacuum (FlcVcm); All the quantized
dualistic dynamical properties of the SchEl are results of the participate of
its WllSpr ElmElcChrg in the Furth's stochastic boson circular harmonic
oscillations. d/ in Nweton's classical motion along a clear-cut smooth thin
line as a result of some interaction of its over spread (OvrSpr) ElmElcChrg,
MgnDplMmn or bare mass with the intensities of some classical fields.

</DOC>
<DOC>
<DOCNO> 71609 </DOCNO>
Theory of Hadronic Atoms


  A review of the modern theory of hadronic atoms based on the non-relativistic
effective Lagrangian approach and ChPT, is given. As an application of the
general framework, we consider the decay of the pi+pi- atom into two neutral
pions, and the energy-level shift of the pi-p atom. The analysis of the decay
width of the pi+pi- atom has been carried out at the first non-leading order in
isospin breaking, and at O(e^2p^2) in ChPT, that results in an accurate
theoretical prediction for this quantity. The study of the pi-p atom
energy-level shift within the same approach clearly demonstrates the necessity
to critically reaccess the values of the pi N scattering lengths, extracted
from the energy-level shift measurement by means of the potential model-based
theoretical analysis. The construction of short-range hadronic potentials from
field theory is also discussed.

</DOC>
<DOC>
<DOCNO> 70751 </DOCNO>
Excited State Contributions to the Heavy Baryon Fragmentation Functions


  Spin dependent fragmentation functions for heavy flavor quarks to fragment
into heavy baryons are calculated in a quark-diquark model. The production of
intermediate spin 1/2 and 3/2 excited states is explicity included. The
resulting $\Lambda_b$ production rate and polarization at LEP energies are in
agreement with experiment. The $\Lambda_c$ and $\Xi_c$ functions are also
obtained. The spin independent $f_1(z)$ is compared to data. The integrated
values for production rates agree with the data.

</DOC>
<DOC>
<DOCNO> 13976 </DOCNO>
Structure determination, valence, and superexchange in the dimerized low


  We report results of a new analysis for the low-temperature structure of
alpha'-NaV2O5 from synchrotron x-ray diffraction experiments. We confirm the
existence of two inequivalent ladder structures in each vanadium layer. Based
on our structural data we perform a bond-valence calculation for the vanadium
sites in the low temperature state. Due to an asymmetric charge ordering we
obtain only two different vanadium valences despite the three inequivalent
sites. This explains the 51V-NMR observation of only two resonant peaks in the
charge ordered phase. By use of a Slater-Koster method to obtain hopping matrix
elements and cluster calculations we obtain effective vanadium-vanadium
hoppings which compare well to LDA results. Using these in a cluster
calculation we obtain a superexchange of 0.047 eV between electrons on
neighbouring rungs of the same ladder for the undistorted phase. For the
distorted phase we find a significant alternation in the shifts of the oxygen
atoms along the legs of one of the two ladder types which leads to a
significant exchange dimerisation \delta_J \approx 0.25.

</DOC>
<DOC>
<DOCNO> 84447 </DOCNO>
Dynamic Cosmic Strings II: Numerical evolution of excited Cosmic Strings


  An implicit, fully characteristic, numerical scheme for solving the field
equations of a cosmic string coupled to gravity is described. The inclusion of
null infinity as part of the numerical grid allows us to apply suitable
boundary conditions on the metric and matter fields to suppress unphysical
divergent solutions. The code is tested by comparing the results with exact
solutions, checking that static cosmic string initial data remain constant when
evolved and undertaking a time dependent convergence analysis of the code. It
is shown that the code is accurate, stable and exhibits clear second order
convergence. The code is used to analyse the interaction between a
Weber--Wheeler pulse of gravitational radiation with the string. The
interaction causes the string to oscillate at frequencies inversely
proportional to the masses of the scalar and vector fields of the string. After
the pulse has largely radiated away the string continues to ring but the
oscillations slowly decay and eventually the variables return to their static
values.

</DOC>
<DOC>
<DOCNO> 122032 </DOCNO>
On the use of a non-extensive distribution in the solar plasma


  We describe the physical motivations why we are urged to look for an ionic
equilibrium distribution function slightly different from the Maxwellian to
calculate nuclear reaction rates in the solar core plasma answering, at the
same time, to a recent paper by Bahcall et al. (astro-ph/0010055).

</DOC>
<DOC>
<DOCNO> 84478 </DOCNO>
Gravity of higher-dimensional global defects


  Solutions of Einstein's equations are found for global defects in a
higher-dimensional spacetime with a nonzero cosmological constant Lambda. The
defect has a (p-1)-dimensional core (brane) and a `hedgehog' scalar field
configuration in the n extra dimensions. For Lambda = 0 and n > 2, the
solutions are characterized by a flat brane worldsheet and a solid angle
deficit in the extra dimensions. For Lambda > 0, one class of solutions
describes spherical branes in an inflating higher-dimensional universe.
Instantons obtained by a Euclidean continuation of such solutions describe
quantum nucleation of the entire inflating brane-world, or of a spherical brane
in an inflating higher-dimensional universe. For Lambda < 0, one class of
solutions exhibits an exponential warp factor. It is similar to spacetimes
previously discussed by Randall and Sundrum for n = 1 and by Gregory for n = 2.

</DOC>
<DOC>
<DOCNO> 122092 </DOCNO>
The Star Clusters in the Irregular Galaxy NGC 4449


  We examine the star clusters in the irregular galaxy NGC 4449. We use a
near-infrared spectrum and broad-band images taken with the HST to place a
limit of 8--15 Myrs on the age of the bright central ojbect in NGC 4449. Its
luminosity and size suggest that it is comparable to young super star clusters.
However, there is a peculiar nucleated-bar structure at the center of this star
cluster, and we suggest that this structure is debris from the interaction that
has produced the counter-rotating gas systems and extended gas streamers in the
galaxy.
  From the images we identify 60 other candidate compact star clusters in NGC
4449. Fourteen of these could be background elliptical galaxies or old globular
star clusters. Of the star clusters, three, in addition to the central object,
are potentially super star clusters, and many others are comparable to the
populous clusters found in the LMC. The star clusters span a large range in
ages with no obvious peak in cluster formation that might be attributed to the
interaction that the galaxy has experienced.

</DOC>
<DOC>
<DOCNO> 84683 </DOCNO>
On the nature of the force acting on a charged classical particle


  In general relativity the gravitational field is a manifestation of spacetime
curvature and unlike the electromagnetic field is not a force field. A particle
falling in a gravitational field is represented by a geodesic worldline which
means that no force is acting on it. If the particle is at rest in a
gravitational field, however, its worldline is no longer geodesic and it is
subjected to a force. The nature of that force is an open question in general
relativity. The aim of this paper is to outline an approach toward resolving it
in the case of classical charged particles which was initiated by Fermi in
1921.

</DOC>
<DOC>
<DOCNO> 71096 </DOCNO>
Quest for the dynamics of $\nu_{mu} \to \nu_{tau}$ conversion


  We perform a quantitative analysis of the capability of K2K, MINOS, OPERA and
a neutrino factory in a muon collider to discriminate the standard mass induced
vacuum oscillation from the pure decoherence solution to the atmospheric
neutrino problem and thereby contribute to unravel the dynamics that governs
the observed $\nu_mu$ disappearence.

</DOC>
<DOC>
<DOCNO> 120141 </DOCNO>
Stellar evolution with rotation VI: The Eddington and Omega-limits, the


  Several properties of massive stars with large effects of rotation and
radiation are studied. We show that there are 2 roots for the equation giving
the rotational velocities at break-up: 1) The usual solution, which is shown to
apply when the Eddington ratio $\Gamma$ of the star is smaller than formally
0.639. 2) Above this value of $\Gamma$, there is a second root, inferior to the
first one, for the break-up velocity. This second solution tends to zero, when
$\Gamma$ tends towards 1. This second root results from the interplay of
radiation and rotation, and in particular from the reduction by rotation of the
effective mass in the local Eddington factor. The analysis made here should
hopefully clarify a recent debate between Langer (\cite{La97,La98}) and Glatzel
(\cite{Gla98}).
  The expression for the global mass loss-rates is a function of both $\Omega$
and $\Gamma$, and this may give raise to extreme mass loss-rates ($\Omega
\Gamma $-limit). In particular, for O-type stars, LBV stars, supergiants and
Wolf-Rayet stars, even slow rotation may dramatically enhance the mass loss
rates. Numerical examples in the range of 9 to 120 M$_{\odot}$ at various
$T_\mathrm{eff}$ are given.

</DOC>
<DOC>
<DOCNO> 178856 </DOCNO>
Nucleon-Nucleon Optical Potentials \and Fusion of $\pi$N, KN, $\pi\pi$


  Several boson exchange potentials, describing the NN interaction $T_\ell\le
300$ MeV with high quality, are extended in their range of applicability as NN
optical models with complex local or separable potentials in r-space or as
complex boundary condition models. We determine in this work the separable
potential strengths or boundary conditions on the background of the Paris,
Nijmegen-I, Nijmegen-II, Reid93, AV18 and inversion potentials. Other hadronic
systems, $\pi$N, KN and $\pi\pi$, are studied with the same token. We use the
latest phase shift analyzes SP00, SM00 and FA00 by Arndt {\em et al.} as input
and thus extent the mentioned potential models from 300 MeV to 3 GeV . The
imaginary parts of the interaction account for loss of flux into direct or
resonant production processes. For a study of resonances and absorption the
partial waves wave functions with physical boundary conditions are calculated.
We display the energy and radial dependences of flux losses and radial
probabilities. The results lend quantitative support for the established mental
image of intermediate elementary particle formation in the spirit of fusion.

</DOC>
<DOC>
<DOCNO> 151806 </DOCNO>
Discrete torsion orbifolds and D-branes


  D-branes on orbifolds with and without discrete torsion are analysed in a
unified way using the boundary state formalism. For the example of the Z2 x Z2
orbifold it is found that both the theory with and without discrete torsion
possess D-branes whose world-volume carries conventional and projective
representations of the orbifold group. The resulting D-brane spectrum is shown
to be consistent with T-duality.

</DOC>
<DOC>
<DOCNO> 102199 </DOCNO>
Bass Numbers of Semigroup-Graded Local Cohomology


  Given a module M over a ring R which has a grading by a semigroup Q, we
present a spectral sequence that computes the local cohomology of M at any
Q-graded ideal I in terms of Ext modules. This method is used to obtain
finiteness results for the local cohomology of graded modules over semigroup
rings; in particular we prove that for a semigroup Q whose saturation is
simplicial, the Bass numbers of such local cohomology modules are finite.
Conversely, if the saturation of Q is not simplicial, one can find a graded
ideal I and a graded R-module M whose local cohomology at I in some degree has
an infinite-dimensional socle. We introduce and exploit the combinatorially
defined essential set of a semigroup.

</DOC>
<DOC>
<DOCNO> 178935 </DOCNO>
Do chemically saturated antihyperon abundancies signal the quark gluon


  We first review the production and the possible chemical equilibration of
strange particles at CERN-SPS energies within a microscopic hadronic transport
calculation. It is shown in particular that the strange quarks are produced
initially via string excitations in the primary, secondary and ternary
interactions. We then further elaborate on a recent idea of antihyperon
production by multi-mesonic reactions like $n_1\pi + n_2 K \to \bar{Y}+p $
corresponding to the inverse of the strong binary baryon-antibaryon
annihilation process. It is argued that by these reactions the (rare)
antihyperons are driven towards local chemical equilibrium with pions, nucleons
and kaons on a timescale of 1--3 fm/c in the still moderately baryon-dense
initial hadronic environment after the termination of the prehadronic string
phase. Accordingly this mechanism can provide a convenient explanation for the
antihyperon yields at CERN-SPS energies without any need of a deconfined quark
gluon plasma phase.

</DOC>
<DOC>
<DOCNO> 69040 </DOCNO>
Approximately self-consistent resummations for the thermodynamics of the


  We propose a gauge-invariant and manifestly UV finite resummation of the
physics of hard thermal/dense loops (HTL/HDL) in the thermodynamics of the
quark-gluon plasma. The starting point is a simple, effectively one-loop
expression for the entropy or the quark density which is derived from the fully
self-consistent two-loop skeleton approximation to the free energy, but subject
to further approximations, whose quality is tested in a scalar toy model. In
contrast to the direct HTL/HDL-resummation of the one-loop free energy, in our
approach both the leading-order (LO) and the next-to-leading order (NLO)
effects of interactions are correctly reproduced and arise from kinematical
regimes where the HTL/HDL are justifiable approximations. The LO effects are
entirely due to the (asymptotic) thermal masses of the hard particles. The NLO
ones receive contributions both from soft excitations, as described by the
HTL/HDL propagators, and from corrections to the dispersion relation of the
hard excitations, as given by HTL/HDL perturbation theory. The numerical
evaluations of our final expressions show very good agreement with lattice data
for zero-density QCD, for temperatures above twice the transition temperature.

</DOC>
<DOC>
<DOCNO> 120221 </DOCNO>
Prospects for the Lensing of Supernovae


  Observations of high redshift type Ia supernovae (SNe) will enable us to
probe the structure of galaxy halos and the composition of dark matter. The
future prospects for this field are briefly discussed here. First the ability
of SN observations to differentiate between dark matter made of macroscopic
compact objects and dark matter made of microscopic particles is reviewed. Then
a new method for probing the structure of galaxy halos and galaxy cluster halos
is described. This method utilizes the correlations between foreground galaxy
light and supernova brightnesses to substantially decrease possible systematic
errors. The technique may be particularly useful for measuring the size of dark
matter halos, a measurement to which the galaxy--galaxy lensing is not well
suited, and the level of substructure in galaxy halos, a problematic prediction
of the cold dark matter model. The required observations of hundreds of SNe at
z ~ 1 are already being proposed for the purposes of cosmological parameter
estimation.

</DOC>
<DOC>
<DOCNO> 102238 </DOCNO>
Exact Solvability of Superintegrable Systems


  It is shown that all four superintegrable quantum systems on the Euclidean
plane possess the same underlying hidden algebra $sl(3)$. The gauge-rotated
Hamiltonians, as well as their integrals of motion, once rewritten in
appropriate coordinates, preserve a flag of polynomials. This flag corresponds
to highest-weight finite-dimensional representations of the $sl(3)$-algebra,
realized by first order differential operators.

</DOC>
<DOC>
<DOCNO> 9810 </DOCNO>
Phase-field modeling of microstructural pattern formation during


  During the directional solidification of peritectic alloys, two stable solid
phases (parent and peritectic) grow competitively into a metastable liquid
phase of larger impurity content than either solid phase. When the parent or
both solid phases are morphologically unstable, i.e., for a small temperature
gradient/growth rate ratio ($G/v_p$), one solid phase usually outgrows and
covers the other phase, leading to a cellular-dendritic array structure closely
analogous to the one formed during monophase solidification of a dilute binary
alloy. In contrast, when $G/v_p$ is large enough for both phases to be
morphologically stable, the formation of the microstructurebecomes controlled
by a subtle interplay between the nucleation and growth of the two solid
phases. The structures that have been observed in this regime (in small samples
where convection effect are suppressed) include alternate layers (bands) of the
parent and peritectic phases perpendicular to the growth direction, which are
formed by alternate nucleation and lateral spreading of one phase onto the
other as proposed in a recent model [R. Trivedi, Metall. Mater. Trans. A 26, 1
(1995)], as well as partially filled bands (islands), where the peritectic
phase does not fully cover the parent phase which grows continuously. We
develop a phase-field model of peritectic solidification that incorporates
nucleation processes in order to explore the formation of these structures.
Simulations of this model shed light on the morphology transition from islands
to bands, the dynamics of spreading of the peritectic phase on the parent phase
following nucleation, which turns out to be characterized by a remarkably
constant acceleration, and the types of growth morphology that one might expect
to observe in large samples under purely diffusive growth conditions.

</DOC>
<DOC>
<DOCNO> 10166 </DOCNO>
Ando, Lavrov, and Segawa Reply


  Authors' Reply to the Comment by Janossy et al. [cond-mat/0005275] on our
article, "Magnetoresistance Anomalies in Antiferromagnetic
YBa_{2}Cu_{3}O_{6+x}: Fingerprints of Charged Stripes" [cond-mat/9905071,
Phys. Rev. Lett. 83, 2813 (1999)].

</DOC>
<DOC>
<DOCNO> 69916 </DOCNO>
Universality and Chaos in Quantum Field Theories


  We investigate the eigenvalue spectrum of the staggered Dirac matrix in SU(3)
gauge theory and in full QCD as well as in quenched U(1) theory on various
lattice sizes. As a measure of the fluctuation properties of the eigenvalues,
we consider the nearest-neighbor spacing distribution, $P(s)$. We further study
two-color QCD at nonzero chemical potential, $\mu$, by constructing the spacing
distribution of adjacent eigenvalues in the complex plane. We find that in all
regions of their phase diagrams, compact lattice gauge theories have bulk
spectral correlations given by random matrix theory, which is an indication for
quantum chaos. In the confinement phase, the low-lying Dirac spectrum of these
quantum field theories is well described by random matrix theory, exhibiting
universal behavior.

</DOC>
<DOC>
<DOCNO> 68584 </DOCNO>
Breaking the Barriers - Uniting Accelerator and Cosmic Ray p-p Cross


  We make a QCD-inspired parameterization of all accelerator data on forward
proton-proton and antiproton-proton scattering amplitudes. Using vector
dominance and the additive quark model, we show that the same parameters also
fit gamma p and gamma gamma interactions. Using the high energy predictions of
our model, along with Glauber theory, we calculate proton-air cross sections at
energies near sqrt s approx 30 TeV. The comparisons of p-air cosmic ray
measurements with our QCD model predictions provide a strong constraint on the
inclusive particle production cross section.

</DOC>
<DOC>
<DOCNO> 13400 </DOCNO>
Applications of Gaussian model of the vortex tangle in the superfluid


  In spite of an appearance of some impressive recent results in understanding
of the superfluid turbulence in HeII they fail to evaluate many characteristics
of vortex tangle needed for both applications and fundamental study. Early we
reported the Gaussian model of the vortex tangle in superfluid turbulent HeII.
That model is just trial distribution functional in space of vortex loop
configurations constructed on the basis of well established properties of
vortex tangle. It is designed to calculate various averages taken over
stochastic vortex loop configurations. In this paper we use this model to
calculate some important characteristics of the vortex tangle. In particular we
evaluate the average superfluid mass current J induced by vortices and the
average energy E associated with the chaotic vortex filament.

</DOC>
<DOC>
<DOCNO> 102380 </DOCNO>
Conservation laws for a class of nonlinear equations with variable


  The conservation laws for a class of nonlinear equations with variable
coefficients on discrete and noncommutative spaces are derived. For discrete
models the conserved charges are constructed explicitly. The applications of
the general method include equations on quantum plane, supersymmetric equations
for chiral and antichiral supermultiplets as well as auxiliary equations of
integrable models - principal chiral model and various cases of nonlinear Toda
lattice equations.

</DOC>
<DOC>
<DOCNO> 67637 </DOCNO>
Neutrino Masses and Grand Unification


  We discuss some models of neutrino masses and mixings in the context of
fermion masses in Grand Unified Theories.

</DOC>
<DOC>
<DOCNO> 102674 </DOCNO>
Little groups of irreps of O(3), SO(3), and the infinite axial subgroups


  Little groups are enumerated for the irreps and their components in any basis
of O(3) and SO(3) up to rank 9, and for all irreps of C$_{\infty}$, C$_{\infty
h}$, C$_{\infty v}$, D$_{\infty}$ and D$_{\infty h}$. The results are obtained
by a new chain criterion, which distinguishes massive (rotationally
inequivalent) irrep basis functions and allows for multiple branching paths,
and are verified by inspection. These results are relevant to the determination
of the symmetry of a material from its linear and nonlinear optical properties
and to the choices of order parameters for symmetry breaking in liquid
crystals.

</DOC>
<DOC>
<DOCNO> 11901 </DOCNO>
Soft Ellipsoid Model for Gaussian Polymer Chains


  A soft ellipsoid model for Gaussian polymer chains is studied, following an
idea proposed by Murat and Kremer [J. Chem. Phys. 108, 4340 (1998)]. In this
model chain molecules are mapped onto ellipsoids with certain shapes, and to
each shape a monomer density is assigned. In the first part of the work, the
probabilities for the shapes and the associated monomer densities are studied
in detail for Gaussian chains. Both quantities are expressed in terms of simple
approximate formulae. The free energy of a system composed of many ellipsoids
is given by an intramolecular part accounting for the internal degrees of
freedom and an intermolecular part following from pair interactions between the
monomer densities. Structural and kinetic properties of both homogeneous
systems and binary mixtures are subsequently studied by Monte-Carlo
simulations. It is shown that the model provides a powerful phenomenological
approach for investigating polymeric systems on semi-macroscopic time and
length scales.

</DOC>
<DOC>
<DOCNO> 11151 </DOCNO>
Real-Axis Solution of Eliashberg Equations in Various Order-Parameter


  In the present work we calculate the theoretical tunneling conductance curves
of SIN junctions involving high-Tc superconductors, for different possible
symmetries of the order parameter (s, d, s+id, s+d, anisotropic s and extended
s). To do so, we solve the real-axis Eliashberg equations in the case of an
half-filled infinite band. We show that some of the peculiar characteristics of
HTSC tunneling curves (dip and hump at eV > Delta, broadening of the gap peak,
zero bias and so on) can be explained in the framework of the Migdal-Eliashberg
theory. The theoretical dI/dV curves calculated for the different symmetries at
T=4 K are then compared to various experimental tunneling data obtained in
optimally-doped BSCCO, TBCO, HBCO, LSCO and YBCO single crystals. To best fit
the experimental data, the scattering by non-magnetic impurities has to be
taken into account, thus limiting the sensitivity of this procedure in
determining the exact gap symmetry of these materials. Finally, the effect of
the temperature on the theoretical tunneling conductance is also discussed and
the curves obtained at T=2 K are compared to those given by the analytical
continuation of the imaginary-axis solution.

</DOC>
<DOC>
<DOCNO> 102011 </DOCNO>
One Form of Successive Approximation Method and Choice Problem


  A mathematical model of Subject behaviour choice is proposed. The background
of the model is the concept of two preference relations determining Subject
behaviour. These are an "internal" or subjective preference relation and an
"external" or objective preference relation.
  The first (internal) preference relation is defined by some partial order on
a set of states of the Subject. The second (external) preference relation on
the state set is defined by a mapping from the state set to another partially
ordered set. The mapping will be called evaluation mapping (function).
  We research the process of external preference maximization in a fashion that
uses the external preference as little as possible. On the contrary, Subject
may use the internal preference without any restriction.
  The complexity of a maximization procedure depends on the disagreement
between these preferences. To solve the problem we apply some kind of the
successive approximations methods. In terms of evaluation mappings this method
operates on a decomposition of the mapping into a superposition of several
standard operations and "easy" mappings (see the details below). Obtained in
such way superpositions are called approximating forms.
  We construct several such forms and present two applications. One of them is
concerned with a hypothetic origin of logic. The other application provides a
new interpretation of the well known model of human choice by Lefebvre. The
interpretation seems to suggest a justification different from the one proposed
by Lefebvre himself.

</DOC>
<DOC>
<DOCNO> 71596 </DOCNO>
O(alpha_s) corrections to longitudinal and transverse W-bosons in top


  In this talk we consider the O(alpha_s) radiative corrections to the decay of
an unpolarized top quark into a bottom quark and a W gauge boson where the
helicities of the W are specified as transverse-plus, transverse-minus and
longitudinal. The O(alpha_s) radiative corrections lower the normalized
longitudinal rate Gamma_L/Gamma by 0.8%. We find that the normalized
transverse-plus rate Gamma_+/Gamma, which vanishes at the Born term level for
m_b->0, receives radiative correction contributions at the sub-percent level.
Our results are discussed in the light of recent measurements of the helicity
content of the W in top quark decays by the CDF Collaboration.

</DOC>
<DOC>
<DOCNO> 9411 </DOCNO>
Thermal conductivity of Mg-doped CuGeO_3 at very low temperatures: Heat


  Thermal conductivity \kappa is measured at very low temperatures down to 0.28
K for pure and Mg-doped CuGeO_3 single crystals. The doped samples carry larger
amount of heat than the pure sample at the lowest temperature. This is because
antiferromagnetic magnons appear in the doped samples and are responsible for
the additional heat conductivity, while \kappa of the pure sample represents
phonon conductivity at such low temperatures. The maximum energy of the magnon
is estimated to be much lower than the spin-Peierls-gap energy. The result
presents the first example that \kappa at very low temperatures probes the
magnon transport in disorder-induced antiferromagnetic phase of spin-gap
systems.

</DOC>
<DOC>
<DOCNO> 122313 </DOCNO>
Verifying the use of supernovae as probes of the cosmic expansion


  We present preliminary results of a follow-up survey which aims to
characterise in detail those galaxies which hosted Type Ia supernovae found by
the Supernova Cosmology Project (SCP). Our survey has two components: Hubble
Space Telescope imaging with STIS and Keck spectroscopy with ESI, the goal
being to classify each host galaxy into one of three broad
morphological/spectral classes and hence to investigate the dependence of
supernovae properties on host galaxy type over a large range in redshift. Of
particular interest is the supernova Hubble diagram characterised by host
galaxy class which suggests that most of the scatter arises from those
occurring in late-type irregulars. Supernovae hosted by (presumed dust-free)
E/S0 galaxies closely follow the adopted SCP cosmological model. Although
larger datasets are required, we cannot yet find any significant difference in
the light curves of distant supernovae hosted in different galaxy types.

</DOC>
<DOC>
<DOCNO> 13266 </DOCNO>
Static Charge Coupling of Intrinsic Josephson Junction


  A microscopic theory for the coupling of intrinsic Josephson oscillations due
to charge fluctuations on the quasi two-dimensional superconducting layers is
presented. Thereby in close analogy to the normal state the effect of the
scalar potential on the transport current is taken into account consistently.
The dispersion of collective modes is derived and an estimate of the coupling
constant is given. It is shown that the correct treatment of the quasiparticle
current is essential in order to get the correct position of Shapiro steps. In
this case the influence of the coupling on dc-properties like the $I-V$-curve
is negligible.

</DOC>
<DOC>
<DOCNO> 101650 </DOCNO>
Critical Behavior in Lossy Source Coding


  The following critical phenomenon was recently discovered. When a memoryless
source is compressed using a variable-length fixed-distortion code, the fastest
convergence rate of the (pointwise) compression ratio to the optimal $R(D)$
bits/symbol is either $O(\sqrt{n})$ or $O(\log n)$. We show it is always
$O(\sqrt{n})$, except for discrete, uniformly distributed sources.

</DOC>
<DOC>
<DOCNO> 14016 </DOCNO>
Resistance Spikes at Transitions between Quantum Hall Ferromagnets


  We report a new manifestation of first-order magnetic transitions in
two-dimensional electron systems. This phenomenon occurs in aluminum arsenide
quantum wells with sufficiently low carrier densities and appears as a set of
hysteretic spikes in the resistance of a sample placed in crossed parallel and
perpendicular magnetic fields, each spike occurring at the transition between
states with different partial magnetizations. Our experiments thus indicate
that the presence of magnetic domains at the transition starkly increases
dissipation, an effect also suspected in other ferromagnetic materials.
Analysis of the positions of the transition spikes allows us to deduce the
change in exchange-correlation energy across the magnetic transition, which in
turn will help improve our understanding of metallic ferromagnetism.

</DOC>
<DOC>
<DOCNO> 71844 </DOCNO>
Small-x Resummation and HERA Structure Function Data


  We apply our systematic NLO small x resummation of singlet splitting
functions to the scaling violations of structure functions and compare the
results with data. We develop various theoretical tools which are needed in
order to relate resummed parton distributions to measurable structure
functions, and we present results from a variety of fits to HERA data for the
structure functions F_2 and F_L using the resummation. The behaviour of the
singlet splitting functions at small x and fixed Q^2 is effectively
parametrized as x^{-lambda}. We find that, for lambda small or negative, the
resummed description of scaling violations may be phenomenologically as good as
or even better than the standard next-to-leading order treatment. However, the
best fit gluon density and value of alpha_s can be significantly modified by
the resummation.

</DOC>
<DOC>
<DOCNO> 40151 </DOCNO>
Search for charged Higgs bosons in e+e- collisions at energies up to


  The data collected at centre-of-mass energies of 188.6 GeV by ALEPH at LEP,
corresponding to an integrated luminosity of 176.2 pb-1, are analysed in a
search for pair-produced charged Higgs bosons H+/-. Three analyses are employed
to select the taunutaunu, taunucs and cscs final states. No evidence for a
signal is found. Upper limits are set on the production cross section as a
function of the branching fraction BR(H+ to tau nu) and of the mass M(H+),
assuming that the sum of the branching ratios is equal to one. In the framework
of a two-Higgs-doublet model, charged Higgs bosons with masses below 65.4
GeV/c2 are excluded at 95% confidence level independently of the decay mode.

</DOC>
<DOC>
<DOCNO> 84352 </DOCNO>
High energy physics and the very-early Universe with LISA


  Gravitational wave experiments will play a key role in the investigation of
the frontiers of cosmology and the structure of fundamental fields at high
energies, by detecting, or setting strong upper-limits to, the primordial
gravitational wave background produced in the early-Universe. Here we discuss
the impact of space-borne laser interferometric detectors operating in the
low-frequency window ($\sim 1 \mu$Hz - 1 Hz); the aim of our analysis is to
assess the detectability of a primordial background characterized by a
fractional energy density $\Omega \sim 10^{-16} - 10^{-15}$, which is
consistent with the prediction of "slow-roll" inflationary models.

</DOC>
<DOC>
<DOCNO> 100888 </DOCNO>
Rigidity and quasi-rigidity of extremal cycles in Hermitian symmetric


  I use local differential geometric techniques to prove that the algebraic
cycles in certain extremal homology classes in Hermitian symmetric spaces are
either rigid (i.e., deformable only by ambient motions) or quasi-rigid (roughly
speaking, foliated by rigid subvarieties in a nontrivial way).
  These rigidity results have a number of applications: First, they prove that
many subvarieties in Grassmannians and other Hermitian symmetric spaces cannot
be smoothed (i.e., are not homologous to a smooth subvariety). Second, they
provide characterizations of holomorphic bundles over compact Kahler manifolds
that are generated by their global sections but that have certain polynomials
in their Chern classes vanish (for example, c_2 = 0, c_1c_2 - c_3 = 0, c_3 = 0,
etc.).

</DOC>
<DOC>
<DOCNO> 68907 </DOCNO>
Generalized Gerasimov-Drell-Hearn Sum Rule for the Proton-Neutron


  Applications of the chiral expansion to generalize the Gerasimov-Drell-Hearn
sum rule for finite $Q^2$ are discussed. The observation of several authors
that the corrections to the leading order contributions are large and limit the
applicability to a very small range in $Q^2$, are valid when considering the
sum rule for protons and neutrons, separately. When using the proton-neutron
difference, the chiral expansion may be valid to considerably higher momentum
transfers where hadronic degrees of freedom at large distances may connect up
with quark and gluon degrees of freedom. This could mark the first time that
nucleon structure is decribed by fundamental theory from large to small
distances.

</DOC>
<DOC>
<DOCNO> 151378 </DOCNO>
On Noncommutative Open String Theories


  We investigate new compactifications of OM theory giving rise to a 3+1
dimensional open string theory with noncommutative $x^0$-$x^1$ and $x^2$-$x^3$
coordinates. The theory can be directly obtained by starting with a D3 brane
with parallel (near critical) electric and magnetic field components, in the
presence of a RR scalar field. The magnetic parameter permits to interpolate
continuously between the $x^0$-$x^1$ noncommutative open string theory and the
$x^2$-$x^3$ spatial noncommutative U(N) super Yang-Mills theory. We discuss
$SL(2,Z)$ transformations of this theory. Using the supergravity description of
the large $N$ limit, we also compute corrections to the quark-antiquark Coulomb
potential arising in the NCOS theory.

</DOC>
<DOC>
<DOCNO> 40643 </DOCNO>
Hadron Formation in Deep-Inelastic Positron Scattering in a Nuclear


  The influence of the nuclear medium on the production of charged hadrons in
semi-inclusive deep-inelastic scattering has been studied by the HERMES
experiment at DESY using a 27.5 GeV positron beam. The differential
multiplicity of charged hadrons and identified charged pions from nitrogen
relative to that from deuterium has been measured as a function of the virtual
photon energy \nu and the fraction z of this energy transferred to the hadron.
There are observed substantial reductions of the multiplicity ratio R_M^h at
low \nu and at high z, both of which are well described by a
gluon-bremsstrahlung model of hadronization. A significant difference of the
\nu-dependence of R_M^h is found between positive and negative hadrons. This is
interpreted in terms of a difference between the formation times of protons and
pions, using a phenomenological model to describe the \nu- and z-dependence of
R_M^h.

</DOC>
<DOC>
<DOCNO> 122452 </DOCNO>
Large scale grain mantle disruption in the Galactic Center


  We present observations of C2H5OH toward molecular clouds in Sgr A, Sgr B2
and associated with thermal and non-thermal features in the Galactic center.
C2H5OH emission in Sgr A and Sgr B2 is widespread, but not uniform. C2H5OH
emission is much weaker or it is not detected in some molecular clouds in both
complexes, in particular those with radial velocities between 70 and 120 km/s.
While most of the clouds associated with the thermal features do not show
C2H5OH emission, that associated with the Non-Thermal Radio Arc shows emission.
The fractional abundance of C2H5OH in most of the clouds with radial velocities
between 0 and 70 km/s in Sgr A and Sgr B2 is relatively high, of few 1e-8. The
C2H5OH abundance decreases by more than one order of magnitude (aprox. 1e-9) in
the clouds associated with the thermal features. The large abundance of C2H5OH
in the gas-phase indicates that C2H5OH has formed in grains and released to
gas-phase by shocks in the last aprox. 1e5 years.

</DOC>
<DOC>
<DOCNO> 151785 </DOCNO>
Exact Solutions of Multi-Vortices and False Vacuum Bubbles in


  We consider the noncommutative Abelian-Higgs theory and construct new types
of exact multi-vortex solutions that solve the static equations of motion. They
in general do not follow from the BPS equations; only for some specific values
of parameters, they satisfy the BPS equations saturating the Bogomol'nyi bound.
We further consider the Abelian-Higgs theory with more complicated scalar
potential allowing unstable minima and construct exact solutions of
noncommutative false vacuum bubble with integer magnetic flux. The classical
stability of the solutions is discussed.

</DOC>
<DOC>
<DOCNO> 174569 </DOCNO>
Potential and limitations of nucleon transfer experiments with


  As a tool for studying the structure of nuclei far off stability the
technique of gamma-ray spectroscopy after low-energy single-nucleon transfer
reactions with radioactive nuclear beams in inverse kinematics was
investigated. Modules of the MINIBALL germanium array and a thin
position-sensitive parallel plate avalanche counter (PPAC) to be employed in
future experiments at REX-ISOLDE were used in a test experiment performed with
a stable 36S beam on deuteron and 9Be targets. It is demonstrated that the
Doppler broadening of gamma lines detected by the MINIBALL modules is
considerably reduced by exploiting their segmentation, and that for beam
intensities up to 10^6 particles/s the PPAC positioned around zero degrees with
respect to the beam axis allows not only to significantly reduce the gamma
background by requiring coincidences with the transfer products but also to
control the beam and its intensity by single particle counting. The predicted
large neutron pickup cross sections of neutron-rich light nuclei on 2H and 9Be
targets at REX-ISOLDE energies of 2.2 MeV A are confirmed.

</DOC>
<DOC>
<DOCNO> 120037 </DOCNO>
The ORFEUS II Echelle Spectrum of HD 93521: A reference for interstellar


  During the second flight of the ORFEUS-SPAS mission in November/December
1996, the Echelle spectrometer was used extensively by the Principal and Guest
Investigator teams as one of the two focal plane instruments of the ORFEUS
telescope. The spectrum of HD 93521 was obtained during this mission with a
total integration time of 1740 s. This spectrum shows numerous sharp
interstellar absorption lines. We identified 198 lines of molecular hydrogen
including at least 7 lines with a high velocity component. Also most of the 67
identified interstellar metal lines are visible with a high velocity component.
  We present plots of the complete ORFEUS Echelle spectrum together with tables
of all identified interstellar absorption lines including all 14 detectable HI
lines. In addition several identified stellar lines, partially with narrow
absorption components, and stellar wind lines are given in a separate table.

</DOC>
<DOC>
<DOCNO> 120315 </DOCNO>
1.65 micron (H-band) surface photometry of galaxies. V: Profile


  We present near-infrared H-band (1.65 micron) surface brightness profile
decomposition for 1157 galaxies in five nearby clusters of galaxies: Coma,
A1367, Virgo, A262 and Cancer, and in the bridge between Coma and A1367 in the
"Great Wall". The optically selected (m_p<=16.0) sample is representative of
all Hubble types, from E to Irr+BCD, except dE and of significantly different
environments, spanning from isolated regions to rich clusters of galaxies. We
model the surface brightness profiles with a de Vaucouleurs r^(1/4) law (dV),
with an exponential disk law (E), or with a combination of the two (B+D). From
the fitted quantities we derive the H band effective surface brightness (mu_e)
and radius (r_e) of each component, the asymptotic magnitude H_T and the light
concentration index C_31. We find that: i) Less than 50% of the Elliptical
galaxies have pure dV profiles. The majority of E to Sb galaxies is best
represented by a B+D profile. All Scd to BCD galaxies have pure exponential
profiles. ii) The type of decomposition is a strong function of the total H
band luminosity (mass), independent of the Hubble classification: the fraction
of pure exponential decompositions decreases with increasing luminosity, that
of B+D increases with luminosity. Pure dV profiles are absent in the low
luminosity range L_H<10^(10) L_solar and become dominant above 10^(11) L_solar.

</DOC>
<DOC>
<DOCNO> 12187 </DOCNO>
Dynamical process for switching dynamics between metastable ordered


  We propose a dynamical mechanism of the two-way switching between the
metastable state and the stable state, which has been found in experiments of
photoinduced reversible magnetization and photoinduced structural phase
transition. We find that the two-way switching with a non-symmetry breaking
perturbation such as illumination is possible only in systems with appropriate
parameters. We make it clear that the existence of two time scales in the
dynamical process is important for the two-way switching.

</DOC>
<DOC>
<DOCNO> 117085 </DOCNO>
Formation of Root Singularities on the Free Surface of a Conducting


  The formation of singularities on a free surface of a conducting ideal fluid
in a strong electric field is considered. It is found that the nonlinear
equations of two-dimensional fluid motion can be solved in the small-angle
approximation. This enables us to show that for almost arbitrary initial
conditions the surface curvature becomes infinite in a finite time.

</DOC>
<DOC>
<DOCNO> 70356 </DOCNO>
Life time of resonances in transport simulations


  We calculate the life time of a resonance in our recently developed framework
for a test-particle description of transport processes for states with
continuous mass spectra. The result differs from the expression commonly used
in transport simulations but agrees with the one derived by Danielewicz and
Pratt relating the life time to the scattering phase shift.

</DOC>
<DOC>
<DOCNO> 68873 </DOCNO>
Measuring the relative CP-even and CP-odd Yukawa couplings of a Higgs


  We study a possibility of a measurement of muon Yukawa couplings in s-channel
Higgs boson production at a muon collider with transversely polarized beams. We
investigate sensitivity to the relative size of the CP-odd and CP-even muon
Yukawa couplings. Provided the event rate observed justify the operation of the
$\mu^+\mu^-$ Higgs boson factory, we have found that polarization degree 40% is
sufficient to resolve the CP nature of a single resonance as well as
disentangle it from two overlapping CP conserving resonances.

</DOC>
<DOC>
<DOCNO> 67770 </DOCNO>
Parametrisation of F_2^gamma at low Q^2 and of sigma(gamma,gamma) and


  A parametrisation of the real photon structure function F_2^gamma in the low
Q^2, low x region is formulated. It includes both the VMD and the QCD
components, the latter suitably extrapolated to the low Q^2 region and based on
arbitrary parton distributions in the photon. The parametrisation used together
with the GRV and GRS' parton densities describes reasonably well the existing
high energy data on F_2^gamma, sigma(gamma,gamma) and the low Q^2 data on
sigma(gamma^*, gamma). Predictions for sigma(gamma,gamma) and for sigma(gamma^*
,gamma) for energies which may become accessible in future linear colliders are
also given.

</DOC>
<DOC>
<DOCNO> 39659 </DOCNO>
Polarized Parton Distribution Functions in the Nucleon


  Polarized parton distribution functions are determined by using world data
from the longitudinally polarized deep inelastic scattering experiments. A new
parametrization of the parton distribution functions is adopted by taking into
account the positivity and the counting rule. From the fit to the asymmetry
data A_1, the polarized distribution functions of u and d valence quarks, sea
quarks, and gluon are obtained. The results indicate that the quark spin
content is \Delta\Sigma=0.20 and 0.05 in the leading order (LO) and the
next-to-leading-order (NLO) MS-bar scheme, respectively. However, if x
dependence of the sea-quark distribution is fixed at small x by "perturbative
QCD" and Regge theory, it becomes \Delta \Sigma=0.24 ~ 0.28 in the NLO. The
small-x behavior cannot be uniquely determined by the existing data, which
indicates the importance of future experiments. From our analysis, we propose
one set of LO distributions and two sets of NLO ones as the
longitudinally-polarized parton distribution functions.

</DOC>
<DOC>
<DOCNO> 68153 </DOCNO>
Phenomenology of stops, sbottoms, tau-sneutrinos, and staus at an e+e-


  We discuss production and decays of stops, sbottoms, tau-sneutrinos, and
staus in e+e- annihilation in the energy range \sqrt{s} = 0.5-1 TeV. We present
numerical predictions within the Minimal Supersymmetric Standard Model for
cross sections and decay rates, including one-loop radiative corrections as
well as initial state radiation. We also study the importance of beam
polarization for the determination of the underlying SUSY parameters. Moreover,
we make a comparison of the potential to study squarks and sleptons of the 3rd
generation between Tevatron, LHC, and Linear Collider.

</DOC>
<DOC>
<DOCNO> 68778 </DOCNO>
Limits on the size of extra dimensions


  We give a brief summary of present bounds on the size of possible
extra-dimensions from collider experiments.

</DOC>
<DOC>
<DOCNO> 12536 </DOCNO>
Symmetry broken motion of a periodically driven Brownian particle:


  We report a theoretical study of an overdamped Brownian particle dynamics in
the presence of both a spatially modulated one-dimensional periodic potential
and a periodic alternating force (AF). As the periodic potential has a low
symmetry (a ratchet potential) the Brownian particle displays a broken symmetry
motion with a nonzero time average velocity. By making use of the Green
function method and a mapping to the theory of Brillouin bands the probability
distribution of the particle coordinate is derived and the nonlinear dependence
of the macroscopic velocity on the frequency and the amplitude of AF is found.
In particular, our theory allows to go beyond the adiabatic limit and to
explain the peculiar reversal of the velocity sign found previously in the
numerical analysis.

</DOC>
<DOC>
<DOCNO> 100433 </DOCNO>
Similarity problems and length


  This is a survey of the author's recent results on the Kadison and Halmos
similarity problems and the closely connected notion of ``length'' of an
operator algebra.

</DOC>
<DOC>
<DOCNO> 99405 </DOCNO>
Canonical momenta of nonlinear combat


  The context of nonlinear combat calls for more sophisticated measures of
effectiveness. We present a set of tools that can be used as such supplemental
indicators, based on stochastic nonlinear multivariate modeling used to
benchmark Janus simulation to exercise data from the U.S. Army National
Training Center (NTC). As a prototype study, a strong global optimization tool,
adaptive simulated annealing (ASA), is used to explicitly fit Janus data,
deriving coefficients of relative measures of effectiveness, and developing a
sound intuitive graphical decision aid, canonical momentum indicators (CMI),
faithful to the sophisticated algebraic model. We argue that these tools will
become increasingly important to aid simulation studies of the importance of
maneuver in combat in the 21st century.

</DOC>
<DOC>
<DOCNO> 120964 </DOCNO>
Structure and evolution of the inner Milky Way galaxy: results from


  The DENIS/ISOGAL near/mid-IR survey of the Milky Way for the first time
probes stellar populations in the innermost obscured regions of our galaxy.
Ages, metallicities and extinction-corrected luminosities are derived for these
stars individually. An old metal-rich population dominates in the inner
galactic Bulge, but there are also indications for the presence of a younger
population. The inner Bulge has a tri-axial shape, as traced by depth effects
on the observed luminosity distributions.

</DOC>
<DOC>
<DOCNO> 71038 </DOCNO>
Leading-Order Gluon-Pair Production from a Space-Time Dependent


  We describe gluon-pair production from a space-time dependent chromofield via
vacuum polarization within the framework of the background field method of QCD.
The processes we consider are first order in the action. We derive the
corresponding source terms for gluon pair production for situations that can be
described by a 1+1 dimensional approach. Especially, we observe that within the
range of applicability of our approach the principal contribution to gluon
production is included. Gluon production from a space-time dependent
chromofield will play an important role in the production and evolution of the
quark-gluon plasma in ultra relativistic heavy-ion collisions at RHIC and LHC.

</DOC>
<DOC>
<DOCNO> 13714 </DOCNO>
$T_c$ suppression in co-doped striped cuprates


  We propose a model that explains the reduction of $T_c$ due to the pinning of
stripes by planar impurity co-doping in cuprates. A geometrical argument about
the planar fraction of carriers affected by stripe pinning leads to a a linear
$T_c$ suppression as a function of impurity concentration $z$. The critical
value $z_c$ for the vanishing of superconductivity is shown to scale like
$T_c^2$ in the under-doped regime and becomes universal in the optimally- and
over-doped regimes. Our theory agrees very well with the experimental data in
single- and bi-layer cuprates co-doped with Zn, Li, Co, etc...

</DOC>
<DOC>
<DOCNO> 70297 </DOCNO>
Quintessence Model and Cosmic Microwave Background


  A particular kind of quintessence is considered, with equation of motion
$p_Q/\rho_Q = -1$, corresponding to a cosmological term with time-dependence
$\Lambda(t) = \Lambda(t_0) (R(t_0)/R(t))^{P}$ and we examine how values of
$\Omega_m$ and $\Omega_{\Lambda}$ depend on $P$.

</DOC>
<DOC>
<DOCNO> 170789 </DOCNO>
Teleporting Noncommuting Qubits Require Maximal Entanglement


  Very recently, it was shown by Ghosh, Kar, Roy and Sen (\emph{Entanglement
vs. Noncommutativity in Teleportation}, quant-ph/0010012) that if it is \emph{a
priori} known that the state to be teleported is from a commuting set of
qubits, a separable channel is sufficient. We show that 1 ebit of entanglement
is a necessary resource to teleport a qubit even when it is known to be one of
two noncommuting states.

</DOC>
<DOC>
<DOCNO> 7899 </DOCNO>
Domino effect for world market fluctuations


  In order to emphasize cross-correlations for fluctuations in major market
places, series of up and down spins are built from financial data. Patterns
frequencies are measured, and statistical tests performed. Strong
cross-correlations are emphasized, proving that market moves are collective
behaviors.

</DOC>
<DOC>
<DOCNO> 10386 </DOCNO>
A Bosonic Model of Hole Pairs


  We numerically investigate a bosonic representation for hole pairs on a
two-leg t-J ladder where hard core bosons on a chain represent the hole pairs
on the ladder. The interaction between hole pairs is obtained by fitting the
density profile obtained with the effective model to the one obtained with the
\tj model, taking into account the inner structure of the hole pair given by
the hole-hole correlation function. For these interactions we calculate the
Luttinger liquid parameter, which takes the universal value $K_{\rho}=1$ as
half filling is approached, for values of the rung exchange $J'$ between strong
coupling and the isotropic case. The long distance behavior of the hole-hole
correlation function is also investigated. Starting from large $J'$, the
correlation length first increases as expected, but diminishes significantly as
$J'$ is reduced and bound holes sit mainly on adjacent rungs. As the isotropic
case is approached, the correlation length increases again. This effect is
related to the different kind of bonds in the region between the two holes of a
hole pair when they move apart.

</DOC>
<DOC>
<DOCNO> 152384 </DOCNO>
On the effective character of a non abelian DBI action


  We study the way Lorentz covariance can be reconstructed from Matrix Theory
as a IMF description of M-theory. The problem is actually related to the
interplay between a non abelian Dirac-Born-Infeld action and Super-Yang-Mills
as its generalized non-relativistic approximation. All this physics shows up by
means of an analysis of the asymptotic expansion of the Bessel functions
$K_\nu$ that profusely appear in the computations of amplitudes at finite
temperature and solitonic calculations. We hope this might help to better
understand the issue of getting a Lorentz covariant formulation in relation
with the $N\to +\infty$ limit. There are also some computations that could be
of some interest in Relativistic Statistical Mechanics.

</DOC>
<DOC>
<DOCNO> 9245 </DOCNO>
Dipole scattering in polarization induced two-dimensional electron gases


  Unusually large spontaneous and piezoelectric fields in the III-V nitrides
have led to the making of an entirely new class of two-dimensional electron
gas. Fluctuation from a perfectly periodic binary structure in highly polar
semiconductor alloys present the same physical situation as a random
distribution of microscopic dipoles. The excess dipole distribution in the
barrier layers is evaluated by a method similar to the virtual crystal
approximation. It is shown that the mobility of electrons in the
two-dimensional electron gas formed in highly polar heterostructures is
intrinsically limited by scattering from such dipoles.

</DOC>
<DOC>
<DOCNO> 10356 </DOCNO>
Molecular motor that never steps backwards


  We investigate the dynamics of a classical particle in a one-dimensional
two-wave potential composed of two periodic potentials, that are
time-independent and of the same amplitude and periodicity. One of the periodic
potentials is externally driven and performs a translational motion with
respect to the other. It is shown that if one of the potentials is of the
ratchet type, translation of the potential in a given direction leads to motion
of the particle in the same direction, whereas translation in the opposite
direction leaves the particle localized at its original location. Moreover,
even if the translation is random, but still has a finite velocity, an
efficient directed transport of the particle occurs.

</DOC>
<DOC>
<DOCNO> 119428 </DOCNO>
ISO Observations of Pre-Main Sequence and Vega-type Stars


  I present an overview of the results obtained by the Infrared Space
Observatory (ISO) on circumstellar material in pre-main sequence (PMS) stars.
Results obtained for embedded YSOs, Herbig Ae/Be systems and T Tauri stars are
reviewed and their connection to the disks around Vega-type systems is
discussed. Although the gas contents of the PMS environment will also be
discussed briefly, this review will mainly focus on the composition, mineralogy
and evolution of dust in these systems, and the results will be compared to
those found in other classes of objects, including solar system comets.

</DOC>
<DOC>
<DOCNO> 121846 </DOCNO>
Mapping the Galactic Halo IV. Finding Distant Giants Reliably with the


  We critically examine the use of the Washington photometric system (with the
51 filter) for identifying distant halo giants. While this is the most powerful
photometric technique for isolating G and K giant stars, spectroscopic
follow-up of giant candidates is vital. There are two situations in which
interlopers outnumber genuine giants in the diagnostic M-51/M-T2 plot, and are
indistinguishable photometrically from the giants. (1) In deep surveys covering
tens of square degrees, very metal-poor halo dwarfs are a significant
contaminant. An example is our survey of the outer halo (Morrison et al. 2000,
Dohm-Palmer et al. 2000), where these metal-poor dwarfs dominate the number of
photometric giant candidates at magnitudes fainter than V = 18 and cannot be
isolated photometrically. (2) In deep surveys of smaller areas with low
photometric precision, most objects in the giant region of the color-color plot
are dwarfs whose photometric errors have moved them there. Color errors in M-51
and M-T2 need to be smaller than 0.03 mag to avoid this problem. An example of
a survey whose photometric errors place the giant identifications under
question is the survey for extra-tidal giants around the Carina dwarf
spheroidal of Majewski et al. (2000a). Accurate photometry and spectroscopic
follow-up of giant candidates are essential when using the Washington system to
identify the rare outer-halo giants.

</DOC>
<DOC>
<DOCNO> 80657 </DOCNO>
Temperature Independent Renormalization of Finite Temperature Field


  We analyse 4-dimensional massive $\vp^4$ theory at finite temperature T in
the imaginary-time formalism. We present a rigorous proof that this quantum
field theory is renormalizable, to all orders of the loop expansion. Our main
point is to show that the counterterms can be chosen temperature independent,
so that the temperature flow of the relevant parameters as a function of $T$
can be followed. Our result confirms the experience from explicit calculations
to the leading orders. The proof is based on flow equations, i.e. on the
(perturbative) Wilson renormalization group. In fact we will show that the
difference between the theories at T>0 and at T=0 contains no relevant terms.
Contrary to BPHZ type formalisms our approach permits to lay hand on
renormalization conditions and counterterms at the same time, since both appear
as boundary terms of the renormalization group flow. This is crucial for the
proof.

</DOC>
<DOC>
<DOCNO> 118956 </DOCNO>
First results of the ROSEBUD Dark Matter experiment


  Rare Objects SEarch with Bolometers UndergrounD) is an experiment which
attempts to detect low mass Weak Interacting Massive Particles (WIMPs) through
their elastic scattering off Al and O nuclei. It consists of three small
sapphire bolometers (of a total mass of 100 g) with NTD-Ge sensors in a
dilution refrigerator operating at 20 mK in the Canfranc Underground
Laboratory. We report in this paper the results of several runs (of about 10
days each) with successively improved energy thresholds, and the progressive
background reduction obtained by improvement of the radiopurity of the
components and subsequent modifications in the experimental assembly, including
the addition of old lead shields. Mid-term plans and perspectives of the
experiment are also presented.

</DOC>
<DOC>
<DOCNO> 122507 </DOCNO>
Slow modes in Keplerian disks


  Low-mass disks orbiting a massive body can support "slow" normal modes, in
which the eigenfrequency is much less than the orbital frequency. Slow modes
are lopsided, i.e., the azimuthal wavenumber m=1. We investigate the properties
of slow modes, using softened self-gravity as a simple model for collective
effects in the disk. We employ both the WKB approximation and numerical
solutions of the linear eigenvalue equation. We find that all slow modes are
stable. Discrete slow modes can be divided into two types, which we label
g-modes and p-modes. The g-modes involve long leading and long trailing waves,
have properties determined by the self-gravity of the disk, and are only
present in narrow rings or in disks where the precession rate is dominated by
an external potential. In contrast, the properties of p-modes are determined by
the interplay of self-gravity and other collective effects. P-modes involve
both long and short waves, and in the WKB approximation appear in degenerate
leading/trailing pairs. Disks support a finite number---sometimes zero---of
discrete slow modes, and a continuum of singular modes.

</DOC>
<DOC>
<DOCNO> 70675 </DOCNO>
Supersymmetric Scaling Violations (I). Solving the Supersymmetric DGLAP


  We analize the renormalization group equations of supersymmetric QCD with N=1
for the evolution of parton distributions. For this purpose we develope a
simple recursive algorithm in x-space to include both regular regions and
supersymmetric regions in the evolution in the step approximation.
Supersymmetric distributions are generated within a radiative model, with
vanishing initial conditions for the superpartners. Here we focus on a scenario
with broken susy, characterized by a lighter gluino coupled to the standard
evolution and a decoupled scalar quark. Predictions for the all the
distributions are presented.

</DOC>
<DOC>
<DOCNO> 70448 </DOCNO>
Yukawa Unification as a Window into the Soft Supersymmetry Breaking


  We study Yukawa unification, including the effects of a physical neutrino
mass consistent with the Superkamiokande observations, in a string/$D$-brane
inspired Pati-Salam model which allows the most general non-universal scalar
and gaugino masses, including the usual $D$-term contributions which arise in
SO(10). We investigate how the tight constraints from rare decays such as $b
\to s \gamma$ and $\tau \to \mu \gamma$ can provide information about the
family dependent supersymmetry breaking soft Lagrangian, for example the
trilinears associated with the second and third family. Many of our results
also apply to SO(10) to which the model approximately reduces in a limiting
case. In both models we find that Yukawa unification is perfectly viable
providing the non-universal soft masses have particular patterns. In this sense
Yukawa unification acts as a window into the soft supersymmetry breaking
Lagrangian.

</DOC>
<DOC>
<DOCNO> 102887 </DOCNO>
Transgression on Hyperk\"{a}hler Manifolds and Generalized Higher


  We propose a generalization of the Hodge $dd_c$-lemma to the case of
hyperk\"ahler manifolds. As an application of this result we derive the global
construction of the fourth order transgression of the Chern character forms of
hyperholomorphic bundles over compact hyperk\"ahler manifolds. At the second
part of the paper we consider the fourth order transgression for the infinite
dimensional bundle arising from local families of hyperk\"ahler manifolds. We
propose a local construction of the fourth order transgression of the Chern
character form. We derive an explicit expression for arising hypertorsion
differential form. It's zero-degree part may be expressed in terms of the
Laplace operators defined on the fibers of the local family.

</DOC>
<DOC>
<DOCNO> 7887 </DOCNO>
Critical Dynamics of Singlet Excitations in a Frustrated Spin System


  We construct and analyze a two-dimensional frustrated quantum spin model with
plaquette order, in which the low-energy dynamics is controlled by spin
singlets. At a critical value of frustration the singlet spectrum becomes
gapless, indicating a quantum transition to a phase with dimer order. This T=0
transition belongs to the 3D Ising universality class, while at finite
temperature a 2D Ising critical line separates the plaquette and dimerized
phases.
 The magnetic susceptibility has an activated form throughout the phase
diagram, whereas the specific heat exhibits a rich structure and a power law
dependence on temperature at the quantum critical point.
 We argue that the novel quantum critical behavior associated with singlet
criticality discussed in this work can be relevant to a wide class of quantum
spin systems, such as antiferromagnets on Kagome and pyrochlore lattices, where
the low-energy excitations are known to be spin singlets, as well as to the
CAVO lattice and several recently discovered strongly frustrated square-lattice
antiferromagnets.

</DOC>
<DOC>
<DOCNO> 40457 </DOCNO>
Prospect for Searches for Gluinos and Squarks at a Tevatron Tripler


  We examine the discovery potential for SUSY new physics at a p{\bar p}
collider upgrade of Tevatron with \sqrt s = 5.4 TeV and luminosity L ~= 4\times
10^{32} cm^{-2}s^{-1} (the Tripler). We consider the reach for gluinos and
squarks using the experimental signatures with large missing transverse energy
(\met) of jets + \met and 1l + jets + \met (where l=electron or muon) within
the framework of minimal supergravity. The Tripler's strongest reach for the
gluino is 1060 GeV for the jets + \met channel and 1140 GeV for the 1l + jets +
\met channel for 30 fb^{-1} of integrated luminosity (approximately two years
running time). This is to be compared with the Tevatron where the reach is
440(460) GeV in the jets + \met channel for 15(30) fb^{-1} of integrated
luminosity.

</DOC>
<DOC>
<DOCNO> 83442 </DOCNO>
Utilizing the World Wide Web as an Encyclopedia: Extracting Term


  In this paper, we propose a method to extract descriptions of technical terms
from Web pages in order to utilize the World Wide Web as an encyclopedia. We
use linguistic patterns and HTML text structures to extract text fragments
containing term descriptions. We also use a language model to discard
extraneous descriptions, and a clustering method to summarize resultant
descriptions. We show the effectiveness of our method by way of experiments.

</DOC>
<DOC>
<DOCNO> 116308 </DOCNO>
A Simple Explanation for Taxon Abundance Patterns


  For taxonomic levels higher than species, the abundance distributions of
number of subtaxa per taxon tend to approximate power laws, but often show
strong deviationns from such a law. Previously, these deviations were
attributed to finite-time effects in a continuous time branching process at the
generic level. Instead, we describe here a simple discrete branching process
which generates the observed distributions and find that the distribution's
deviation from power-law form is not caused by disequilibration, but rather
that it is time-independent and determined by the evolutionary properties of
the taxa of interest. Our model predicts-with no free parameters-the
rank-frequency distribution of number of families in fossil marine animal
orders obtained from the fossil record. We find that near power-law
distributions are statistically almost inevitable for taxa higher than species.
The branching model also sheds light on species abundance patterns, as well as
on links between evolutionary processes, self-organized criticality and
fractals.

</DOC>
<DOC>
<DOCNO> 71817 </DOCNO>
A Novel Mass Hierarchy and Discrete Excitation Spectra from


  We elaborate further on a recently proposed scenario for generating a mass
hierarchy through quantum fluctuations of a single D3 brane, which represents
our world embedded in a bulk five-dimensional space time. In this scenario, the
quantum fluctuations of the D3-brane world in the bulk direction, quantified to
leading order via a `recoil' world-sheet logarithmic conformal field theory
approach, result in the dynamical appearance of a supersymmetry breaking
(obstruction) scale alpha. This may be naturally taken to be at the TeV range,
in order to provide a solution to the conventional gauge-hierarchy problem. The
bulk spatial direction is characterized by the dynamical appearance of an
horizon located at +- 1/alpha, inside which the positive energy conditions for
the existence of stable matter are satisfied. To ensure the correct value of
the four-dimensional Planck mass, the bulk string scale M_s is naturally found
to lie at an intermediate energy scale of 10^{14} GeV. As an exclusive feature
of the D3-brane quantum fluctuations (`recoil') we find that, for any given
M_5, there is a discrete mass spectrum for four-dimensional Kaluza-Klein (KK)
modes of bulk graviton and/or scalar fields. KK modes with masses 0 <= m <
sqrt{2}alpha << M_s are found to have wavefunctions peaked, and hence
localized, on the D3 brane at z=0.

</DOC>
<DOC>
<DOCNO> 13411 </DOCNO>
Failure regime in (1+1) dimensions in fibrous materials


  In this paper, we introduce a model for fracture in fibrous materials that
takes into account the rupture height of the fibers, in contrast with previous
models. Thus, we obtain the profile of the fracture and calculate its
roughness, defined as the variance around the mean height. We investigate the
relationship between the fracture roughness and the fracture toughness.

</DOC>
<DOC>
<DOCNO> 11037 </DOCNO>
Predictability, complexity and learning


  We define {\em predictive information} $I_{\rm pred} (T)$ as the mutual
information between the past and the future of a time series. Three
qualitatively different behaviors are found in the limit of large observation
times $T$: $I_{\rm pred} (T)$ can remain finite, grow logarithmically, or grow
as a fractional power law. If the time series allows us to learn a model with a
finite number of parameters, then $I_{\rm pred} (T)$ grows logarithmically with
a coefficient that counts the dimensionality of the model space. In contrast,
power--law growth is associated, for example, with the learning of infinite
parameter (or nonparametric) models such as continuous functions with
smoothness constraints. There are connections between the predictive
information and measures of complexity that have been defined both in learning
theory and in the analysis of physical systems through statistical mechanics
and dynamical systems theory. Further, in the same way that entropy provides
the unique measure of available information consistent with some simple and
plausible conditions, we argue that the divergent part of $I_{\rm pred} (T)$
provides the unique measure for the complexity of dynamics underlying a time
series. Finally, we discuss how these ideas may be useful in different problems
in physics, statistics, and biology.

</DOC>
<DOC>
<DOCNO> 121772 </DOCNO>
NICMOS Coronagraphic Observations of 55 Cancri


  We present new near-infrared (1.1-micron) observations of the circumstellar
environment of the planet-bearing star 55 Cancri. With these Hubble Space
Telescope images we are unable to confirm the observation of bright scattered
radiation at longer NIR wavelengths previously reported by Trilling & Brown
(1998), and Trilling, Brown & Rivkin (2000). NICMOS coronagraphic images with
detection sensitivities to ~ 100 microJy arcsec$^{-2}$ at 1.1 microns in the
region 28 - 60 AU from the star fail to reveal any significant excess flux in
point- spread-function (PSF) subtracted images taken in two Hubble Space
Telescope orbits. These new observations place flux densities in the 19-28 AU
zone at a factor of ten or more below the reported ground-based observations.
Applying a suite of a dozen well-matched coronagraphic reference PSFs,
including one obtained in the same orbits as the observations of 55 Cnc,
yielded consistently null results in detecting a disk. We also searched for,
and failed to find, a suggested flux-excess anisotropy in the ratio of ~1.7:1
in the circumstellar background along and orthogonal to the plane of the
putative disk. We suggest that, if such a disk does exist, then the total
1.1-micron spectral flux density in an annular zone 28 - 42 AU from the star
must be no more than ~0.4mJy, at least ten times smaller than suggested by
Trilling and Brown, upon which their very large estimate for the total dust
mass (0.4~$M_{\earth}$) was based. Based on the far infrared and submillimeter
flux of this system and observations of scattered light and thermal emission
from other debris disks, we also expect the intensity of the scattered light to
be at least an order of magnitude below our upper limits.

</DOC>
<DOC>
<DOCNO> 100111 </DOCNO>
Variational-Wavelet Approach to RMS Envelope Equations


  We present applications of variational-wavelet approach to nonlinear
(rational) rms envelope equations. We have the solution as a multiresolution
(multiscales) expansion in the base of compactly supported wavelet basis. We
give extension of our results to the cases of periodic beam motion and
arbitrary variable coefficients. Also we consider more flexible variational
method which is based on biorthogonal wavelet approach.

</DOC>
<DOC>
<DOCNO> 116810 </DOCNO>
Suppression of beam breakup instability in a long train by introducing


  Interaction between the bunches in the NLC main linac via long range
wakefields can cause a beam breakup instability. Although the magnitude of the
long range wakefields for an ideal NLC structure is below the instability
threshold, the wake increases when structure manufacturing errors are taken
into account. In case of large errors, the developing instability can result in
the projected emittance dilution of the bunch train. To suppress the
instability, we propose to introduce an energy spread between the bunches,
similar to the BNS energy spread for damping of the beam breakup within a
single bunch. Based on simple estimates, we show that the energy spread of
order of 1-2% should be enough for suppression of the instability. The results
of computer simulations with the simulation code LIAR confirm theoretical
estimates and indicate that both the tolerances for structure misalignments and
the incoming beam jitter can be considerably loosened by introducing the energy
spread within the beam.

</DOC>
<DOC>
<DOCNO> 71884 </DOCNO>
Nuclear Effects on the UHE Neutrino-Nucleon Deep Inelastic Scattering


  Using a recent parametrization of nuclear effects in parton distribution
functions we calculate the neutrino-nucleon cross section at energies relevant
for ultra high energy neutrino telescopes. The modification of the cross
section in comparison with the calculation using parton densities in free
nucleons is of the order of few per cent for the parameter range of interest in
neutrino telescopes (A=10 and E=10$^6$ GeV) and it reaches 20 % at the highest
energies (E=10$^{12}$ GeV) and for the largest nuclear size (A=190) considered.

</DOC>
<DOC>
<DOCNO> 100492 </DOCNO>
Approximately finitely acting operator algebras


  Let E be an operator algebra on a Hilbert space with finite-dimensional
generated C*-algebra. A classification is given of the locally finite algebras
and the operator algebras obtained as limits of direct sums of matrix algebras
over E with respect to star-extendible homomorphisms. The invariants in the
algebraic case consist of an additive semigroup, with scale, which is a right
module for the semiring $V_E = Hom_u(E \otimes \sK, E \otimes \sK)$ of unitary
equivalence classes of star-extendible homomorphisms. This semigroup is
referred to as the dimension module invariant. In the operator algebra case the
invariants consist of a metrized additive semigroup with scale and a
contractive right module $V_E$-action. Subcategories of algebras determined by
restricted classes of embeddings, such as 1-decomposable embeddings between
digraph algebras, are also classified in terms of simplified dimension module
invariants.

</DOC>
<DOC>
<DOCNO> 100721 </DOCNO>
Finite and p-adic polylogarithms


  The finite n-th polylogarithm li_n(z) in Z/p[z] is defined as the sum on k
from 1 to p-1 of z^k/k^n. We state and prove the following theorem. Let
Li_k:C_p to C_p be the p-adic polylogarithms defined by Coleman. Then a certain
linear combination F_n of products of polylogarithms and logarithms, with
coefficients which are independent of p, has the property that p^{1-n}
DF_n(z^p) reduces modulo p>n+1 to li_{n-1}(z) where D is the Cathelineau
operator z(1-z) d/dz. A slightly modified version of this theorem was
conjectured by Kontsevich. This theorem is used by Elbaz-Vincent and Gangl to
deduce functional equations of finite polylogarithms from those of complex
polylogarithms.

</DOC>
<DOC>
<DOCNO> 121622 </DOCNO>
Photometric redshifts and selection of high redshift galaxies in the NTT


  We present and compare in this paper new photometric redshift catalogs of the
galaxies in three public fields: the NTT Deep Field, the HDF-N and the HDF-S.
Photometric redshifts have been obtained for thewhole sample, by adopting a
$\chi^2$ minimization technique on a spectral library drawn from the Bruzual
and Charlot synthesis models, with the addition of dust and intergalactic
absorption. The accuracy, determined from 125 galaxies with known spectroscopic
redshifts, is $\sigma_z\sim 0.08 (0.3)$ in the redshift intervals $z=0-1.5
(1.5-3.5)$. The global redshift distribution of I-selected galaxies shows a
distinct peak at intermediate redshifts, z~0.6 at I_{AB}<26 and z~0.8 at
I_{AB}<27.5 followed by a tail extending to z~6. We also present for the first
time the redshift distribution of the total IR-selected sample to faint limits
($Ks \leq 21$ and $J\leq22$). It is found that the number density of galaxies
at 1.25<z<1.5 is ~ 0.1 /arcmin^22 at J<=21 and ~1./arcmin^2} at J<22, and drops
to 0.3/arcmin^2 (at J<22) at 1.5<z<2. The HDFs data sets are used to compare
the different results from color selection criteria and photometric redshifts
in detecting galaxies in the redshift range 3.5<z<4.5 Photometric redshifts
predict a number of high z candidates in both the HDF-N and HDF-S that is
nearly 2 times larger than color selection criteria, and it is shown that this
is primarily due to the inclusion of dusty models that were discarded in the
original color selection criteria by Madau et al 1998. In several cases, the
selection of these objects is made possible by the constraints from the IR
bands. Finally, it is shown that galactic M stars may mimic z>5 candidates in
the HDF filter set and that the 4 brightest candidates at $z>5$ in the HDF-S
are indeed most likely M stars. (ABRIDGED)

</DOC>
<DOC>
<DOCNO> 121120 </DOCNO>
A modification of the Monte Carlo method for simulation of radiative


  We propose a method of simulation that is based on the averaging of formal
solutions of the transfer equation by taking the integral by the Monte Carlo
method. This method is used to compute two models, which correspond to the
limiting cases of hot gas and cold background radiation and of hot background
radiation and cold gas, for E-methanol emission from a compact homogeneous
spherical region. We analyse model level populations by using rotational
diagrams in the limiting cases mentioned above. Model optical depths of the
lines with frequencies below 300 GHz up to J=11 inclusive are given.

</DOC>
<DOC>
<DOCNO> 7828 </DOCNO>
A Mechanism for Cutting Carbon Nanotubes with a Scanning Tunneling


  We discuss the local cutting of single-walled carbon nanotubes by a voltage
pulse to the tip of a scanning tunneling microscope. The tip voltage ($\mid V
\mid \ge $~3.8 eV) is the key physical quantity in the cutting process. After
reviewing several possible physical mechanisms we conclude that the cutting
process relies on the weakening of the carbon-carbon bonds through a
combination of localized particle-hole excitations induced by inelastically
tunneling electrons and elastic deformation due to the electric field between
tip and sample. The carbon network releases part of the induced mechanical
stress by forming topological defects that act as nucleation centers for the
formation of dislocations that dynamically propagate towards bond-breaking.

</DOC>
<DOC>
<DOCNO> 68285 </DOCNO>
New Formulation of Matter Effects on Neutrino Mixing and CP Violation


  Within the framework of three lepton families we have derived an exact and
compact formula to describe the matter effect on neutrino mixing and CP
violation. This model- and parametrization-independent result can be
particularly useful for recasting the fundamental lepton flavor mixing matrix
from a variety of long-baseline neutrino experiments.

</DOC>
<DOC>
<DOCNO> 152171 </DOCNO>
Simple models with Alice fluxes


  We introduce two simple models which feature an Alice electrodynamics phase.
In a well defined sense the Alice flux solutions we obtain in these models obey
first order equations similar to those of the Nielsen-Olesen fluxtube in the
abelian higgs model in the Bogomol'nyi limit. Some numerical solutions are
presented as well.

</DOC>
<DOC>
<DOCNO> 178462 </DOCNO>
Partial dynamical symmetry in a fermion system


  The relevance of the partial dynamical symmetry concept for an interacting
fermion system is demonstrated. Hamiltonians with partial SU(3) symmetry are
presented in the framework of the symplectic shell-model of nuclei and shown to
be closely related to the quadrupole-quadrupole interaction. Implications are
discussed for the deformed light nucleus $^{20}$Ne.

</DOC>
<DOC>
<DOCNO> 170356 </DOCNO>
Dynamical localization and signatures of classical phase space


  We study the dynamical localization of cold atoms in Fermi accelerator both
in position space and in momentum space. We report the role of classical phase
space in the development of dynamical localization phenomenon. We provide set
of experimentally assessable parameters to perform this work in laboratory.

</DOC>
<DOC>
<DOCNO> 80838 </DOCNO>
Critical exponents and equation of state of three-dimensional spin


  Three-dimensional spin models of the Ising and XY universality classes are
studied by a combination of high-temperature expansions and Monte Carlo
simulations. Critical exponents are determined to very high precision. Scaling
amplitude ratios are computed via the critical equation of state. Our results
are compared with other theoretical computations and with experiments, with
special emphasis on the lambda transition of 4He.

</DOC>
<DOC>
<DOCNO> 83153 </DOCNO>
SATEN: An Object-Oriented Web-Based Revision and Extraction Engine


  SATEN is an object-oriented web-based extraction and belief revision engine.
It runs on any computer via a Java 1.1 enabled browser such as Netscape 4.
SATEN performs belief revision based on the AGM approach. The extraction and
belief revision reasoning engines operate on a user specified ranking of
information. One of the features of SATEN is that it can be used to integrate
mutually inconsistent commensuate rankings into a consistent ranking.

</DOC>
<DOC>
<DOCNO> 118422 </DOCNO>
The Propagation of Magneto-Centrifugally Launched Jets: I


  We present simulations of the propagation of magnetized jets. This work
differs from previous studies in that the cross-sectional distributions of the
jets's state variables are derived from analytical models for
magneto-centrifugal launching. The source is a magnetized rotator whose
properties are specfied as boundary conditions. The jets in these simulations
are considerably more complex than the ``top-hat''constant density etc.
profiles used in previous work. We find that density and magnetic field
stratification (with radius) in the jet leads to new behavior including the
separation of an inner jet core from a low density collar. We find this {\it
jet within a jet} structure, along with the magnetic stresses, leads to
propagation behaviors not observed in previous simulation studies. Our
methodology allows us to compare MHD jets from different types of sources whose
properties could ultimately be derived from the behavior of the propagating
jets.

</DOC>
<DOC>
<DOCNO> 8760 </DOCNO>
Thomas-Fermi Theory


  This is a brief review of the Thomas-Fermi ("statistical" or "density
functional") theory of atoms and molecules.

</DOC>
<DOC>
<DOCNO> 121171 </DOCNO>
Chemical analysis of 8 recently discovered extra-solar planet host stars


  We present the chemical analysis of a new set of stars known to harbor low
mass companions, namely HD 1237, HD 52265, HD 82943, HD 83443, HD 169830, and
HD 202206. In addition, we have also analyzed HD 13445 and HD 7528}, already
studied elsewhere. The abundances of C and alpha-elements O, S, Si, Ca and Ti
are presented and discussed in the context of the metallicity distribution of
the stars with extra-solar planets. We compare the metallicity distribution of
stars with planets with the same distribution of field dwarfs. The results
further confirm that stars with planets are over-abundant in [Fe/H].

</DOC>
<DOC>
<DOCNO> 8600 </DOCNO>
Ion-Beam Induced Current in High-Resistance Materials


  The peculiarities of electric current in high-resistance materials, such as
semiconductors or semimetals, irradiated by ion beams are considered. It is
shown that after ion--beam irradiation an unusual electric current may arise
directed against the applied voltage. Such a negative current is a transient
effect appearing at the initial stage of the process. The possibility of using
this effect for studying the characteristics of irradiated materials is
discussed. A new method for defining the mean projected range of ions is
suggested.

</DOC>
<DOC>
<DOCNO> 71796 </DOCNO>
Neutralino Warm Dark Matter


  In the supersymmetric (SUSY) standard model, the lightest neutralino may be
the lightest SUSY particle (LSP), and it is is a candidate of the dark matter
in the universe. The LSP dark matter might be produced by the non-thermal
process such as heavy particle decay after decoupling of the thermal relic LSP.
If the produced LSP is relativistic, and does not scatter enough in the thermal
bath, the neutralino LSP may contribute as the warm dark matter (WDM) to wash
out the small scale structure of O(0.1) Mpc. In this letter we calculate the
energy reduction of the neutralino LSP in the thermal bath and study whether
the LSP can be the WDM. If temperature of the production time T_I is smaller
than 5MeV, the bino-like LSP can be the WDM and may contribute to the
small-scale structure of O(0.1) Mpc. The Higgsino-like LSP might also work as
the WDM if T_I< 2MeV. The wino-like LSP cannot be the WDM in the favoured
parameter region.

</DOC>
<DOC>
<DOCNO> 169624 </DOCNO>
Stochastic Resonance and Nonlinear Response by NMR Spectroscopy


  We revisit the phenomenon of quantum stochastic resonance in the regime of
validity of the Bloch equations. We find that a stochastic resonance behavior
in the steady-state response of the system is present whenever the
noise-induced relaxation dynamics can be characterized via a single relaxation
time scale. The picture is validated by a simple nuclear magnetic resonance
experiment in water.

</DOC>
<DOC>
<DOCNO> 8261 </DOCNO>
The puzzle of 90 degree reorientation in the vortex lattice of


  We explain 90 degree reorientation in the vortex lattice of borocarbide
superconductors on the basis of a phenomenological extension of the nonlocal
London model that takes full account of the symmetry of the system. We propose
microscopic mechanisms that could generate the correction terms and point out
the important role of the superconducting gap anisotropy.

</DOC>
<DOC>
<DOCNO> 151112 </DOCNO>
On the Bosonic Spectrum of QCD(1+1) with SU(N) Currents


  In this note we calculate the spectrum of two-dimensional QCD. We formulate
the theory with SU(N_c) currents rather than with fermionic operators. We
construct the Hamiltonian matrix in DLCQ formulation as a function of the
harmonic resolution K and the numbers of flavors N_f and colors N_c. The
resulting numerical eigenvalue spectrum is free from trivial multi-particle
states which obscured previous results. The well-known 't Hooft and large N_f
spectra are reproduced. In the case of adjoint fermions we present some new
results.

</DOC>
<DOC>
<DOCNO> 123162 </DOCNO>
Plerions and pulsar-powered nebulae


  In this brief review, I discuss recent developments in the study of
pulsar-powered nebulae ("plerions"). The large volume of data which has been
acquired in recent years reveals a diverse range of observational properties,
demonstrating how differing environmental and pulsar properties manifest
themselves in the resulting nebulae.

</DOC>
<DOC>
<DOCNO> 40542 </DOCNO>
Momentum Reconstruction and Triggering in the TALAS Detector


  A neural network solution for a complicated experimental High Energy Physics
problem is described. The method is used to reconstruct the momentum and charge
of muons produced in collisions of particle in the ATLAS detector. The
information used for the reconstruction is limited to the output of the outer
layer of the detector, after the muons went through strong and inhomogeneous
magnetic field that have bent their trajectory. It is demonstrated that neural
network solution is efficient in performing this task. It is shown that this
mechanism can be efficient in rapid classification as required in triggering
systems of the future particle accelerators. The parallel processing nature of
the network makes it relevant for hardware realization in the ATLAS triggering
system.

</DOC>
<DOC>
<DOCNO> 170647 </DOCNO>
Quantum channel locally interacting with environment


  The quantum channel subject to local interaction with two-level environment
is studied. The two-level environment is regarded as a quantum bit (qubit) as
well as a pair of particles owned by Alice and Bob. The amount of entanglement
initially shared by Alice and Bob is distributed among these three qubits due
to the interaction. In this model, we show that the singlet fraction of the
decohered quantum channel is uniquely determined by the distributed
entanglement. When the decohered quantum channel is used under the standard
teleportation scheme, the optimal teleportation fidelity is well understood by
considering the remaining entanglement between environment and transmitted
state.

</DOC>
<DOC>
<DOCNO> 122545 </DOCNO>
High-Resolution Keck Spectra of the Associated Absorption Lines in 3C


  Associated absorption lines (AALs) are valuable probes of the gaseous
environments near quasars. Here we discuss high-resolution (6.7 km/s) spectra
of the AALs in the radio-loud quasar 3C 191 (redshift z=1.956). The measured
AALs have ionizations ranging from Mg I to N V, and multi-component profiles
that are blueshifted by ~400 to ~1400 km/s relative to the quasar's broad
emission lines. These data yield the following new results. 1) The density
based on Si II*/Si II lines is ~300 cm-3, implying a distance of ~28 kpc from
the quasar if the gas is photoionized. 2) The characteristic flow time is thus
\~3 x 10^7 yr. 3) Strong Mg I AALs identify neutral gas with very low
ionization parameter and high density. We estimate n_H > 5 x 10^4 cm-3 in this
region, compared to ~15 cm-3 where the N V lines form. 4) The total column
density is N_H < 4 x 10^18 cm-2 in the neutral gas and N_H ~ 2 x 10^20 cm-2 in
the moderately ionized regions. 5) The total mass in the AAL outflow is M ~ 2 x
10^9 Mo, assuming a global covering factor (as viewed from the quasar) of ~10%
>. 6) The absorbing gas only partially covers the background light source(s)
along our line(s) of sight, requiring absorption in small clouds or filaments
<0.01 pc across. The ratio N_H/n_H implies that the clouds have radial (line-
of-sight) thicknesses <0.2 pc. These properties might characterize a sub-class
of AALs that are physically related to quasars but form at large distances. We
propose a model for the absorber in which pockets of dense neutral gas are
surrounded by larger clouds of generally lower density and higher ionization.
This outflowing material might be leftover from a blowout associated with a
nuclear starburst, the onset of quasar activity or a past broad absorption line
(BAL) wind phase.

</DOC>
<DOC>
<DOCNO> 100307 </DOCNO>
Quasi-modular forms and trace functions associated to free boson and


  We study graded traces of vectors in free bosonic vertex operator algebras
and lattice vertex operator algebras. We show in particular that trace
functions in these two theories always have the shape f(q)/\eta(q)^d where f(q)
is quasi-modular in the case of d free bosons, and modular (i.e., a sum of
holomorphic modular forms of various weights) in the case of theories based on
a lattice L of rank d. We also show how spherical harmonic polynomials with
respect to L are related to primary fields in lattice theories.

</DOC>
<DOC>
<DOCNO> 122878 </DOCNO>
Cosmic Momentum Field and Mass Fluctuation Power Spectrum


  We introduce the cosmic momentum field as a new measure of the large-scale
peculiar velocity and matter fluctuation fields. The momentum field is defined
as the peculiar velocity field traced and weighted by galaxies, and is equal to
the velocity field in the linear regime. We show that the radial component of
the momentum field can be considered as a scalar field with the power spectrum
which is practically 1/3 of that of the total momentum field. We present a
formula for the power spectrum directly calculable from the observed radial
peculiar velocity data. The momentum power spectrum is measured for the MAT
sample in the Mark III catalog of peculiar velocities of galaxies. Using the
momentum power spectrum we find the amplitude of the matter power spectrum is
6400^{+2800}_{-1800} and 4500^{+2000}_{-1300} \Omega^{-1.2} (h^{-1} Mpc)^{-3}
at the wavenumbers 0.049 and 0.074 h Mpc^{-1}, respectively, where \Omega is
the density parameter. The 68% confidence limits include the cosmic variance.
The measured momentum and density power spectra together indicate that the
parameter \beta_O = \Omega^{0.6}/b_O = 0.51^{+0.13}_{-0.08} or \Omega =
0.33^{+0.15}_{-0.09} b_O^{5/3} where b_O is the bias factor for optical
galaxies.

</DOC>
<DOC>
<DOCNO> 121688 </DOCNO>
Orientation effects on bent extragalactic jets


  We have investigated how varying several parameters affects the results of a
collision between an extragalactic jet and a dense, intergalactic cloud,
through a series of hydrodynamic simulations. We have produced synthetic radio
images for comparison with observations. These show that a variety of
structures may be produced from simple jet-cloud collisions. Moderate Mach
numbers and density contrasts are needed to produce observable bends. We
investigate the effect of viewing from various angles on the appearance of such
sources.

</DOC>
<DOC>
<DOCNO> 151073 </DOCNO>
A Noncommutative M-Theory Five-brane


  We investigate, in a certain decoupling limit, the effect of having a
constant C-field on the M-theory five-brane using an open membrane probe. We
define an open membrane metric for the five-brane that remains non-degenerate
in the limit. The canonical quantisation of the open membrane boundary leads to
a noncommutative loop space which is a functional analogue of the
noncommutative geometry that occurs for D-branes.

</DOC>
<DOC>
<DOCNO> 12174 </DOCNO>
Elastic Constants of Quantum Solids by Path Integral Simulations


  Two methods are proposed to evaluate the second-order elastic constants of
quantum mechanically treated solids. One method is based on path-integral
simulations in the (NVT) ensemble using an estimator for elastic constants. The
other method is based on simulations in the (NpT) ensemble exploiting the
relationship between strain fluctuations and elastic constants. The strengths
and weaknesses of the methods are discussed thoroughly. We show how one can
reduce statistical and systematic errors associated with so-called primitive
estimators. The methods are then applied to solid argon at atmospheric
pressures and solid helium 3 (hcp, fcc, and bcc) under varying pressures. Good
agreement with available experimental data on elastic constants is found for
helium 3. Predictions are made for the thermal expectation value of the kinetic
energy of solid helium 3.

</DOC>
<DOC>
<DOCNO> 8892 </DOCNO>
Density fluctuations and entropy


  A new functional for the entropy that is asymptotically correct both in the
high and low density limits is proposed. The new form is [
S=S^{(id)}+S^{(ln)}+S^{(r)}+S^{(c)} ] where the new term S^{(c)} depends on the
p-bodies density fluctuations $\alpha_p$ and has the form [ S^{(c)}= <N> {ln
2-1+\sum_{p=2}^\infty \frac{(\ln 2) ^p}{p!}\alpha_p-[ \exp
(\alpha_2-1)-\alpha_2]} +\hat S ], where $\hat S$ renormalizes the ring
approximation S^{(r)}. This result is obtained by analyzing the functional
dependence of the most general expression of the entropy: Two main results for
S^{(c)} are proven: i) In the thermodynamic limit, only the functional
dependence on the one body distribution function survives and ii) by summing to
infinite order the leading contributions in the density a new numerical
expression for the entropy is proposed with a new renormalized ring
approximation included. The relationship of these results to the incompressible
approximation to entropy is discussed.

</DOC>
<DOC>
<DOCNO> 10783 </DOCNO>
Low-dimensional BEC


  The Bose-Einstein condensation (BEC) temperature $T_{c}$ of Cooper pairs
(CPs) created from a very general interfermion interaction is determined for a
{\it linear}, as well as the usual quadratic, energy {\it vs}% center-of-mass
momentum dispersion relation. This $T_{c}$ is then compared to that of Wen &
Kan (1988) in $d=2+\epsilon $ dimensions, for small $\epsilon $, in a geometry
of an infinite stack of parallel (e.g., copper-oxygen) planes as in a cuprate,
and with a new result for linear-dispersion CPs. This allows addressing, as a
rough first approximation, superconductivity for any $d>1$.

</DOC>
<DOC>
<DOCNO> 119772 </DOCNO>
ROSAT/ASCA Observations of a Serendipitous BL Lac Object PKS 2316-423:


  We present the analysis of archival data from ROSAT and ASCA of a
serendipitous BL Lac object PKS 2316-423. Because of its featureless
non-thermal radio/optical continuum, PKS 2316-423 has been called as a BL Lac
candidate in the literature. PKS 2316-423 was evidently variable over the
multiple X-ray observations, in particular, a variable high-energy tail of the
synchrotron radiation is revealed. The X-ray spectral analysis provides further
evidence of the synchrotron nature of its broad-band spectrum: a steep and
downward curving spectrum between 0.1--10 keV, typical of high-energy peaked BL
Lacs (HBL). The spectral energy distribution (SED) through radio-to-X-ray
yields the synchrotron radiation peak at frequency Vp=7.3 10^{15} Hz, with
integrated luminosity of Lsyn=2.1 10^{44} ergs s^{-1}. The averaged SED
properties of PKS 2316-423 are very similar to those ``intermediate'' BL Lac
objects (IBL) found recently in several deep surveys, such as Deep X-ray Radio
Blazar, Radio-Emitting X-ray, and ROSAT-Green Bank surveys. We suggest that PKS
2316-423 is an IBL though it also shows some general features of a HBL.
Actually, this double attribute of PKS 2316-423 provides a good test of the
prediction that an IBL object can show either synchrotron or inverse-Compton
characteristics in different variability states.

</DOC>
<DOC>
<DOCNO> 13111 </DOCNO>
Divergence-free WKB method


  A new semiclassical approach to linear (L) and nonlinear (NL) one-dimensional
Schr\"odinger equation (SE) is presented. Unlike the usual WKB solution, our
solution does not diverge at the classical turning point. For LSE, our
zeroth-order solution, when expanded in powers of \hbar, agrees with the usual
WKB solution. For NLSE, our zeroth-order solution includes quantum corrections
to the Thomas-Fermi solution, thereby giving a smoothly decaying wave function
into the forbidden region.

</DOC>
<DOC>
<DOCNO> 8197 </DOCNO>
Search for Magnetic Field Induced Gap in a High-Tc Superconductor


  Break junctions made of the optimally doped high temperature superconductor
Bi2Sr2Ca2CuO8 with Tc of 90 K has been investigated in magnetic fields up to 12
T, at temperatures from 4.2 K to Tc. The junction resistance varied between
1kOhm and 300kOhm. The differential conductance at low biases did not exhibit a
significant magnetic field dependence, indicating that a magnetic-field-induced
gap (Krishana et al., Science 277 83 (1997)), if exists, must be smaller than
0.25 meV.

</DOC>
<DOC>
<DOCNO> 118184 </DOCNO>
The NASA Astrophysics Data System: Overview


  The NASA Astrophysics Data System Abstract Service has become a key component
of astronomical research. It provides bibliographic information daily, or near
daily, to a majority of astronomical researchers worldwide.
  We describe the history of the development of the system and its current
status.
  We show several examples of how to use the ADS, and we show how ADS use has
increased as a function of time. Currently it is still increasing
exponentially, with a doubling time for number of queries of 17 months.
  Using the ADS logs we make the first detailed model of how scientific
journals are read as a function of time since publication.
  The impact of the ADS on astronomy can be calculated after making some simple
assumptions. We find that the ADS increases the efficiency of astronomical
research by 333 Full Time Equivalent (2000 hour) research years per year, and
that the value of the early development of the ADS for astronomy, compared with
waiting for mature technologies to be adopted, is 2332 FTE research years.
  The ADS is available at http://adswww.harvard.edu/.

</DOC>
<DOC>
<DOCNO> 151056 </DOCNO>
Noncommutative Tachyons


  When unstable Dp-branes in type II string theory are placed in a B-field, the
resulting tachyonic world-volume theory becomes noncommutative. We argue that
for large noncommutativity parameter, condensation of the tachyon as a
noncommutative soliton leads to new decay modes of the Dp-brane into
(p-2)-brane configurations, which we interpret as suitably smeared BPS
D(p-1)-branes. Some of these configurations are metastable. We discuss various
generalizations of this decay process.

</DOC>
<DOC>
<DOCNO> 116505 </DOCNO>
Quasispecies evolution on a fitness landscape with a fluctuating peak


  A quasispecies evolving on a fitness landscape with a single peak of
fluctuating height is studied. In the approximation that back mutations can be
ignored, the rate equations can be solved analytically. It is shown that the
error threshold on this class of dynamic landscapes is defined by the time
average of the selection pressure. In the case of a periodically fluctuating
fitness peak we also study the phase-shift and response amplitude of the
previously documented low-pass filter effect. The special case of a small
harmonic fluctuation is treated analytically.

</DOC>
<DOC>
<DOCNO> 71291 </DOCNO>
Total Cross Sections and Event Properties from Real to Virtual Photons


  A model for total cross sections with virtual photons is presented. In
particular gamma*-p and gamma*-gamma* cross sections are considered. Our
approach extends on a model for photoproduction, where the total cross section
is subdivided into three distinct event classes: direct, VMD and anomalous.
With increasing photon virtuality, the latter two decrease in importance.
Instead Deep Inelastic Scattering dominates, with the direct class being the
O(alpha_s) correction thereof. Hence, the model provides a smooth transition
between the two regions. By the breakdown into different event classes, one may
aim for a complete picture of all event properties.

</DOC>
<DOC>
<DOCNO> 119820 </DOCNO>
Comparison of the ENEAR Peculiar Velocities with the PSCz Gravity Field


  We present a comparison between the peculiar velocity field measured from the
ENEAR all-sky $D_n-\sigma$ catalog and that derived from the galaxy
distribution of the IRAS PSCz redshift survey. The analysis is based on a modal
expansion of these data in redshift space by means of spherical harmonics and
Bessel functions. The effective smoothing scale of the expansion is almost
linear with redshift reaching 1500km/s at 3000km/s. The general flow patterns
in the filtered ENEAR and PSCz velocity fields agree well within 6000km/s,
assuming a linear biasing relation between the mass and the PSCz galaxies. The
comparison allows us to determine the parameter $\beta=\Omega^{0.6}/b$, where
$\Omega$ is the cosmological density parameter and $b$ is the linear biasing
factor. A likelihood analysis of the ENEAR and PSCz modes yields $\beta=0.5 +-
0.1$, in good agreement with values obtained from Tully-Fisher surveys.

</DOC>
<DOC>
<DOCNO> 85179 </DOCNO>
Matters of Gravity, the newsletter of the APS Topical Group on


  Research Briefs:
 Cosmic microwave background anisotropy experiments, by Sean Carroll
 LISA Project Update by Bill Folkner
 An update on the r-mode instability, by Nils Andersson
 Laboratory experiments: news from MG9, by Riley Newman
 Progress toward Commissioning the LIGO detectors, by Stan Whitcomb
 160 Hours of Data Taken on TAMA300, by Seiji Kawamura
 Conference reports:
 Kipfest, by Richard Price
 Third Capra meeting, by Eric Poisson
 GR at the XIIIth Congress on Mathematical Physics, by Abhay Ashtekar
 3rd International LISA Symposium, by Curt Cutler

</DOC>
<DOC>
<DOCNO> 71978 </DOCNO>
Quark model derivation of a NN* (1440) potential


  We derive a $NN^*$(1440) potential from a non-relativistic quark-quark
interaction and a chiral quark cluster model for the baryons. By making use of
the Born-Oppenheimer approximation we examine the most important features of
this interaction in comparison to those obtained from meson-exchange models.

</DOC>
<DOC>
<DOCNO> 118042 </DOCNO>
Simple dynamical models of the Sagittarius dwarf galaxy


  We present two simple dynamical models for Sagittarius based on N-body
simulations of the progressive disruption of a satellite galaxy orbiting for
12.5 Gyr within a realistic Galactic potential. In both models the satellite
initially has observable properties similar to those of current outlying
dwarfs; in one case it is purely stellar while in the other it is embedded in
an extended massive halo. The purely stellar progenitor is a King model with a
total velocity dispersion of 18.9 km/s, a core radius of 0.44 kpc and a tidal
radius of 3 kpc. The initial stellar distribution in the other case follows a
King profile with the same core radius, a slightly larger total velocity
dispersion and similar extent. Both these models are consistent with all
published data on the current Sagittarius system, they match not only the
observed properties of the main body of Sagittarius, but also those reported
for unbound debris at larger distances.

</DOC>
<DOC>
<DOCNO> 101524 </DOCNO>
Local statistics for random domino tilings of the Aztec diamond


  We prove an asymptotic formula for the probability that, if one chooses a
domino tiling of a large Aztec diamond at random according to the uniform
distribution on such tilings, the tiling will contain a domino covering a given
pair of adjacent lattice squares. This formula quantifies the effect of the
diamond's boundary conditions on the behavior of typical tilings; in addition,
it yields a new proof of the arctic circle theorem of Jockusch, Propp, and
Shor. Our approach is to use the saddle point method to estimate certain
weighted sums of squares of Krawtchouk polynomials (whose relevance to domino
tilings is demonstrated elsewhere), and to combine these estimates with some
exponential sum bounds to deduce our final result. This approach generalizes
straightforwardly to the case in which the probability distribution on the set
of tilings incorporates bias favoring horizontal over vertical tiles or vice
versa. We also prove a fairly general large deviation estimate for domino
tilings of simply-connected planar regions that implies that some of our
results on Aztec diamonds apply to many other similar regions as well.

</DOC>
<DOC>
<DOCNO> 13904 </DOCNO>
Superconductivity and Magnetism in a New Class of Heavy-Fermion


  We report a new family of Ce-based heavy-fermion compounds whose electronic
specific heat coefficients range from about 400 to over 700 mJ/mole Ce-K2.
Crystal in this family form as CenTmIn3n+2m, where T=Rh or Ir, n=1 or 2, and
m=1, with a tetragonal structure that can be viewed as n-layers of CeIn3 units
stacked sequentially along the c-axis with intervening m-layers of TIn2.
Ambient and high pressure studies show that the quasi-2D layers of CeIn3
produce unconventional superconducting and magnetic ground states. This family
should enable new understanding of the relationship between magnetism and
superconductivity in heavy-fermion materials and more generally of why
heavy-fermion superconductivity prefers to develop in one structure type and
not another.

</DOC>
<DOC>
<DOCNO> 12256 </DOCNO>
Landau and Dynamical Instabilities of the Superflow of Bose-Einstein


  The superfluidity of Bose-Einstein condensates in optical lattices are
investigated. Apart from the usual Landau instability which occurs when a BEC
flows faster than the speed of sound, the BEC can also suffer a dynamical
instability, resulting in period doubling and other sorts of symmetry breaking
of the system. Such an instability may play a crucial role in the dissipative
motion of a trapped BEC in an optical lattice recently observed [1].

</DOC>
<DOC>
<DOCNO> 169918 </DOCNO>
Nonclassical correlations between photon number and quadrature


  Finite resolution quantum nondemolition (QND) measurements allow a
determination of light field properties while preserving some of the original
quantum coherence of the input state. It is thus possible to measure
correlations between the photon number and a quadrature component of the same
light field mode. Nonclassical features emerge as photon number quantization is
resolved. In particular, a strong anti-correlation of quantization and
coherence is observable in QND measurements of photon number, and a correlation
between measurement induced quantum jumps and quadrature component measurement
results is obtained in QND measurements of quadrature fluctuations in the
photon vacuum. Such nonclassical correlations represent fundamental quantum
properties of the light field and may provide new insights into the nature of
quantization itself.

</DOC>
<DOC>
<DOCNO> 10989 </DOCNO>
Critical Temperature of Ferromagnetic Transition in Three-Dimensional


  Ferromagnetic transition in three-dimensional double-exchange models is
studied by the Monte Carlo method. Critical temperature $T_{\rm c}$ is
precisely determined by finite-size scaling analysis. Strong spin fluctuations
in this itinerant system significantly reduce $T_{\rm c}$ from mean-field
estimates. By choosing appropriate parameters, obtained values of $T_{\rm c}$
quantitatively agree with experiments for the ferromagnetic metal regime of
(La,Sr)MnO$_{3}$, which is a typical perovskite manganite showing colossal
magnetoresistance. This indicates that the double-exchange mechanism alone is
sufficient to explain $T_{\rm c}$ in this material. Critical exponents are also
discussed.

</DOC>
<DOC>
<DOCNO> 121122 </DOCNO>
Box- and peanut-shaped bulges: II. NIR observations


  We have observed 60 edge-on galaxies in the NIR in order to study the stellar
distribution in galaxies with box/peanut-shaped bulges. The much smaller amount
of dust extinction at these wavelengths allows us to identify in almost all
target galaxies with box/peanut-shaped bulges an additional thin, central
component in cuts parallel to the major axis. This structure can be identified
with a bar. The length of this structure scaled by the length of the bulge
correlates with the morphologically classified shape of the bulge. This newly
established correlation is therefore mainly interpreted as the projection of
the bar at different aspect angles. Galaxies with peanut bulges have a bar seen
nearly edge-on and the ratio of bar length to thickness, 14 +/- 4, can be
directly measured for the first time. In addition, the correlation of the
boxiness of bulges with the bar strength indicates that the bar characteristic
could partly explain differences in the bulge shape. Furthermore, a new size
relation between the box/peanut structure and the central bulge is found. Our
observations are discussed in comparison to a N-body simulation for barred
galaxies (Pfenniger & Friedli 1991). We conclude that the inner region of
barred disk galaxies are build up by three distinct components: the spheroidal
bulge, a thin bar, and a b/p structure most likely representing the thick part
of the bar.

</DOC>
<DOC>
<DOCNO> 68130 </DOCNO>
Influence of a medium on pair photoproduction and bremsstrahlung


  The creation of electron-positron pair by a photon and the bremsstrahlung of
an electron in a medium are considered in high-energy region, where influence
of the multiple scattering on the processes (the Landau-Pomeranchuk-Migdal
(LPM) effect) becomes essential. The pair photoproduction probability is
calculated with an accuracy up to the "next to leading logarithm". The integral
characteristics: the radiation length and the total probability of pair
photoproduction are analyzed under influence of the LPM effect, and the
asymptotic expansions of these characteristics are derived.

</DOC>
<DOC>
<DOCNO> 99979 </DOCNO>
Surjective factorization of holomorphic mappings


  We characterize the holomorphic mappings $f$ between complex Banach spaces
that may be written in the form $f=T\circ g$, where $g$ is another holomorphic
mapping and $T$ belongs to a closed surjective operator ideal.

</DOC>
<DOC>
<DOCNO> 101348 </DOCNO>
Sequential Bethe vectors and the quantum Ernst system


  We give a brief review on the use of Bethe ansatz techniques to construct
solutions of recursive functional equations which emerged in a bootstrap
approach to the quantum Ernst system. The construction involves two particular
limits of a rational Bethe ansatz system with complex inhomogeneities. First,
we pinch two insertions to the critical value. This links Bethe systems with
different number of insertions and leads to the concept of sequential Bethe
vectors. Second, we study the semiclassical limit of the system in which the
scale parameter of the insertions tends to infinity.

</DOC>
<DOC>
<DOCNO> 120288 </DOCNO>
Detection of mid-infrared Aromatic Hydrocarbon Emission Features from


  The mid-infrared (5-16 micron) spectral energy distribution for an individual
quiescent molecular cloud in the Small Magellanic Cloud (SMC) was observed
using ISOCAM. The spectrum is dominated by broad emission bands at 6.2, 7.7,
and 11.3 microns, with weaker bands at 8.6 and 12.7 microns. As these are the
same bands, with similar shape and relative strengths, as observed in the ISM
of our Galaxy, the same carriers must exist in both galaxies. The carriers are
widely consider to be large molecules or clusters of aromatic hydrocarbons,
which absorb ultraviolet and visible photons and emit mid-infrared photons
during high-temperature pulses. Based on the brightness of the mid-infrared
emission and the estimated strength of the radiation field in the SMC, the
absorption by aromatic hydrocarbons is of order 10% of total dust absorption,
comparable to the case for Galactic dust. Ultraviolet observations of
extinction of most SMC stars have shown that dust in the SMC does not absorb in
the 2175 Angstrom feature that is so prominent in Milky Way extinction. If
aromatic hydrocarbons and featureless extinction curves were ubiquitous in the
SMC, then we would conclude that aromatic hydrocarbons are not the carriers of
the 2175 Angstrom feature. However, SMC extinction curve measurements are
biased toward hot, luminous stars, where aromatic hydrocarbons are destroyed,
so that the absence of the 2175 Angstrom bump may not be typical of SMC dust.
The presence of aromatic hydrocarbons in the SMC further demonstrate that these
molecules exist even in an interstellar medium with an order-of-magnitude lower
metallicity than in the disk of the Milky Way.

</DOC>
<DOC>
<DOCNO> 40035 </DOCNO>
Structure Functions and Large Q^2 Cross Sections at HERA


  The data collected with the H1 and ZEUS detectors during the running period
1994-99 are used to give an experimental review on the proton structure
functions and the neutral current and charged current large Q^2 cross sections
in e^\pm p scattering at HERA.

</DOC>
<DOC>
<DOCNO> 40227 </DOCNO>
Valence-quark distributions in the pion


  We calculate the pion's valence-quark momentum-fraction probability
distribution using a Dyson-Schwinger equation model. Valence-quarks with an
active mass of 0.30 GeV carry 71% of the pion's momentum at a resolving scale
q_0=0.54 GeV = 1/(0.37 fm). The shape of the calculated distribution is
characteristic of a strongly bound system and, evolved from q_0 to q=2 GeV, it
yields first, second and third moments in agreement with lattice and
phenomenological estimates, and valence-quarks carrying 49% of the pion's
momentum. However, pointwise there is a discrepancy between our calculated
distribution and that hitherto inferred from parametrisations of extant
pion-nucleon Drell-Yan data.

</DOC>
<DOC>
<DOCNO> 151471 </DOCNO>
A Variational Principle for Radial Flows in Holographic theories


  We develop furthur the correspondence between a d+1 dimensional theory and a
d dimensional one with the "radial" (d+1)th corodinate \rho playing the role of
an evolution parameter. We discuss the evolution of an effective action defined
on a d dimensional surface charactarized by \rho by means of a new variational
principle. The conditions under which the flow equations are valid are
discussed in detail as is the choice of boundary conditions. It is explained
how domain walls may be incorporated in the framework and some generalized
junction conditions are obtained. The general principles are illustrated on the
example of a supergravity theory on AdS_{d+1}.

</DOC>
<DOC>
<DOCNO> 9424 </DOCNO>
Small-world networks and the conformation space of a lattice polymer


  We map the conformation space of a simple lattice polymer chain to a network,
where (i) the vertices of the network have a one-to-one correspondence to the
conformations of the chain, and (ii) a link between two vertices indicates the
possibility of switching from one conformation to the other by a single Monte
Carlo move of the chain. We find that the geometric properties of this network
are similar to those of small-world networks, namely, the diameter of
conformation space increases, for large networks, as the logarithm of the
number of conformations, while locally the network appears to have low
dimensionality.

</DOC>
<DOC>
<DOCNO> 117587 </DOCNO>
Neutrino decay and the thermochemical equilibrium of the interstellar


  We calculate the thermochemical equilibrium of the diffuse interstellar
medium, including ionization by a photon flux F_{nu} from neutrino decay. The
main heating mechanism considered is photoelectrons from grains and PAHs. For
the studied range of F_{nu} values, there always exists two regions of
stability (a warm and a cold phase) that can coexist in equilibrium if the
thermal interstellar pressure is between a maximum value P_{max} and a minimum
value P_{min}. High F_{nu} values (~10^4-10^5 cm^{-2} s^{-1}) can be consistent
with observed interstellar pressures only if more efficient sources are heating
the gas. It is shown that a neutrino flux increase (due, for example, to an
increase in the supernova explosion rate) may stimulate the condensation of
cold gas by decreasing P_{max} below the interstellar pressure value.

</DOC>
<DOC>
<DOCNO> 70064 </DOCNO>
Search for new physics in $\Delta S = 2$ two - body (VV, PP, VP) decays


  The $\Delta S = 2$ $b \to \bar d ss$ transition proceeds via the box -
diagram in the Standard Model with a branching ratio calculated to be below
$10^{-11}$, thus providing an appropriate testing ground for physics beyond the
Standard Model. We analyze the $\Delta S = 2$ two - body $B^- \to K^{*-} \bar
K^{*0}$, $B^- \to K^- \bar K^{0}$, $B^- \to K^{*-} \bar K^{0}$ and $B^- \to
K^{-} \bar K^{*0}$ exclusive decays which are driven by the $b \to \bar d ss$
transition, both in the Standard Model and in several extensions of it. The
models considered are the minimal supersymmetric model with and without ${\cal
R}$ parity conservation and two Higgs doublet models. All four modes are found
to have a branching ratio of the order of $10^{-13}$ in the Standard Model,
while the expected branching ratio in the different extensions vary between
$10^{-9} - 10^{-6}$.

</DOC>
<DOC>
<DOCNO> 123174 </DOCNO>
Current Problems for X-ray Emission from Radio Jets


  A list is presented of known extragalactic radio jets which also have
associated X-ray emission. The canonical emission processes for the production
of X-rays are reviewed and the sources are categorized on the basis of our
current understanding. Although it seems clear that the X-ray emission is
non-thermal, the two competing processes, synchrotron and inverse Compton
emissions, arise from extremely high energy (synchrotron) or extremely low
energy (beaming models with IC emission), relativistic electrons. Only
synchrotron self-Compton emission from a few hotspots provides information on
the `normal' energy range of the electrons responsible for the observed radio
emission.

</DOC>
<DOC>
<DOCNO> 121324 </DOCNO>
Non thermal emission from galaxy clusters: radio halos


  The number of diffuse radio halos in clusters of galaxies has grown in recent
years, making it possible to derive statistical properties of these sources and
of the hosting clusters. We show that diffuse sources are associated with X-ray
luminous clusters which have undergone recent merger processes. The radio and
X-ray structures are often similar, and correlations are found between radio
and X-ray parameters. A model for the formation and maintenance of these
sources is suggested, including a first phase of relativistic particle
injection by past major merger events, starbust and AGN activity and a second
phase of reacceleration by the energy supplied from shocks and turbulence in a
recent merger event.

</DOC>
<DOC>
<DOCNO> 68541 </DOCNO>
Color superconductivity in dense quark matter


  I discuss recent developments in our understanding of the
color-superconducting phases of cold, dense quark matter. I describe the phase
diagram as a function of density and the strange quark mass, and outline some
ideas about possible observational consequences of these exotic phases.

</DOC>
<DOC>
<DOCNO> 83168 </DOCNO>
A Finite State and Data-Oriented Method for Grapheme to Phoneme


  A finite-state method, based on leftmost longest-match replacement, is
presented for segmenting words into graphemes, and for converting graphemes
into phonemes. A small set of hand-crafted conversion rules for Dutch achieves
a phoneme accuracy of over 93%. The accuracy of the system is further improved
by using transformation-based learning. The phoneme accuracy of the best system
(using a large set of rule templates and a `lazy' variant of Brill's algoritm),
trained on only 40K words, reaches 99% accuracy.

</DOC>
<DOC>
<DOCNO> 119930 </DOCNO>
Hot HB stars in globular clusters - Physical parameters and consequences


  Atmospheric parameters (effective temperature Teff, surface gravity log g),
masses and helium abundances are derived for 42 hot horizontal branch (HB)
stars in the globular cluster NGC 6752. For 19 stars we derive magnesium and
iron abundances as well and find that iron is enriched by a factor of 50 on
average with respect to the cluster abundance whereas the magnesium abundances
are consistent with the cluster abundance. Radiation pressure may levitate
heavy elements like iron to the surface of the star in a diffusive process.
Taking into account the enrichment of heavy elements in our spectroscopic
analyses we find that high iron abundances can explain part, but not all, of
the problem of anomalously low gravities along the blue HB. The blue HB stars
cooler than about 15,100 K and the sdB stars (Teff > 20,000 K) agree well with
canonical theory when analysed with metal-rich ([M/H] = +0.5) model
atmospheres, but the stars in between these two groups remain offset towards
lower gravities and masses. Deep Mixing in the red giant progenitor phase is
discussed as another mechanism that may influence the position of the blue HB
stars in the (Teff, log g)-plane but not their masses.

</DOC>
<DOC>
<DOCNO> 13678 </DOCNO>
Lagrangian Statistical Mechanics applied to Non-linear Stochastic Field


  We consider non-linear stochastic field equations such as the KPZ equation
for deposition and the noise driven Navier-Stokes equation for hydrodynamics.
We focus on the Fourier transform of the time dependent two point field
correlation, $\Phi_{\bf{k}}(t)$. We employ a Lagrangian method aimed at
obtaining the distribution function of the possible histories of the system in
a way that fits naturally with our previous work on the static distribution.
Our main result is a non-linear integro-differential equation for
$\Phi_{\bf{k}}(t)$, which is derived from a Peierls-Boltzmann type transport
equation for its Fourier transform in time $\Phi_{\bf{k}, \omega}$. That
transport equation is a natural extension of the steady state transport
equation, we previously derived for $\Phi_{\bf{k}}(0)$. We find a new and
remarkable result which applies to all the non-linear systems studied here. The
long time decay of $\Phi_{\bf{k}}(t)$ is described by $\Phi_{\bf{k}}(t) \sim 
\exp(-a|{\bf k}|t^{\gamma})$, where $a$ is a constant and $\gamma$ is system
dependent.

</DOC>
<DOC>
<DOCNO> 8672 </DOCNO>
Kinetics of Ordering in Fluctuation-Driven First-Order Transitions:


  Many systems where interactions compete with each other or with constraints
are well described by a model first introduced by Brazovskii. Such systems
include block copolymers, alloys with modulated phases, Rayleigh-Benard Cells
and type-I superconductors. The hallmark of this model is that the fluctuation
spectrum is isotropic and has a minimum at a nonzero wave vector represented by
the surface of a d-dimensional hyper-sphere. It was shown by Brazovskii that
the fluctuations change the free energy structure from a $ \phi ^{4}$ to a
$\phi ^{6}$ form with the disordered state metastable for all quench depths.
The transition from the disordered to the periodic, lamellar structure changes
from second order to first order and suggests that the dynamics is governed by
nucleation. Using numerical simulations we have confirmed that the equilibrium
free energy function is indeed of a $ \phi ^{6}$ form. A study of the dynamics,
however, shows that, following a deep quench, the dynamics is described by
unstable growth rather than nucleation. A dynamical calculation, based on a
generalization of the Brazovskii calculations shows that the disordered state
can remain unstable for a long time following the quench.

</DOC>
<DOC>
<DOCNO> 119108 </DOCNO>
Three-dimensional modelling of edge-on disk galaxies


  We present detailed three-dimensional modelling of the stellar luminosity
distribution for the disks of 31 relatively nearby (<= 110 Mpc) edge-on spiral
galaxies. In contrast to most of the standard methods available in the
literature we take into account the full three-dimensional information of the
disk. We minimize the difference between the observed 2D-image and an image of
our 3D-disk model integrated along the line of sight. Thereby we specify the
inclination, the fitting function for the z-distribution of the disk, and the
best values for the structural parameters such as scalelength, scaleheight,
central surface brightness, and a disk cut-off radius. From a comparison of two
independently developed methods we conclude, that the discrepancies e.g. for
the scaleheights and scalelengths are of the order of ~10%. These differences
are not due to the individual method itself, but rather to the selected fitting
region, which masks the bulge component, the dust lane, or present foreground
stars. Other serious limitations are small but appreciable intrinsic deviations
of real disks compared to the simple input model. In this paper we describe the
methods and present contour plots as well as radial profiles for all galaxies
without previously published surface photometry. Resulting parameters are given
for the complete sample.

</DOC>
<DOC>
<DOCNO> 122920 </DOCNO>
On the use of a heterogeneous MIMD-SIMD platform to simulate the


  The dynamics of a large stellar (globular) cluster containing N=128,000 stars
has been simulated by a direct summation (O(N$^2$)) method by using a
heterogeneous platform. Preliminary simulations have been carried out on model
systems with and without the presence, in their center of mass, of a black hole
whose mass has been varied from 0.02 to 0.1 times the total mass of the
cluster. These simulations followed the evolution of the globular cluster in
order to describe its dynamics over an interval of time sufficiently large
respect to the internal crossing time. Computations have demonstrated that the
platform heterogeneity, allowing a very efficient use of the computational
resources, can be considered a key feature for sustaining large computational
loads. Our results show that the massive object in the center of the cluster
alters the surrounding star distribution very quickly; the following evolution
is much slower as it occurs via two-body collisional relaxation.

</DOC>
<DOC>
<DOCNO> 120686 </DOCNO>
Convective cores in galactic cooling flows


  We use hydrodynamic simulations with adaptive grid refinement to study the
dependence of hot gas flows in X-ray luminous giant elliptical galaxies on the
efficiency of heat supply to the gas. We consider a number of potential heating
mechanisms including Type Ia supernovae and sporadic nuclear activity of a
central supermassive black hole. As a starting point for this research we use
an equilibrium hydrostatic recycling model (Kritsuk 1996). We show that a
compact cooling inflow develops, if the heating is slightly insufficient to
counterbalance radiative cooling of the hot gas in the central few kiloparsecs.
An excessive heating in the centre, instead, drives a convectively unstable
outflow. We model the onset of the instability and a quasi-steady convective
regime in the core of the galaxy in two-dimensions assuming axial symmetry.
  Provided the power of net energy supply in the core is not too high, the
convection remains subsonic. The convective pattern is dominated by buoyancy
driven large-scale mushroom-like structures. Unlike in the case of a cooling
inflow, the X-ray surface brightness of an (on average) isentropic convective
core does not display a sharp maximum at the centre. A hybrid model, which
combines a subsonic peripheral cooling inflow with an inner convective core,
appears to be stable. We also discuss observational implications of these
results.

</DOC>
<DOC>
<DOCNO> 99416 </DOCNO>
Cayley Hypersurfaces


  We exhibit a family of homogeneous hypersurfaces in affine space, one in each
dimension, generalising the Cayley surface.

</DOC>
<DOC>
<DOCNO> 116567 </DOCNO>
Do The Particles With Nonzero Mass Need Duality ?


  Unsufficiency of conditions for the formation of interference in monoparticle
"which path" experiments is proven. The version of corpuscular interpretation
of diffraction pattern based on the action discreteness is presented, which
makes unnecessary to accredit duality to the particles with nonzero mass. The
experiment to check the above mentioned concepts are proposed.

</DOC>
<DOC>
<DOCNO> 69078 </DOCNO>
A New Model-Independent Method for Extracting Spin-Dependent Cross


  A new method is proposed for extracting limits on spin-dependent WIMP-nucleon
interaction cross sections from direct detection dark matter experiments. The
new method has the advantage that the limits on individual WIMP-proton and
WIMP-neutron cross sections for a given WIMP mass can be combined in a simple
way to give a model-independent limit on the properties of WIMPs scattering
from both protons and neutrons in the target nucleus. Extension of the
technique to the case of a target material consisting of several different
species of nuclei is discussed.

</DOC>
<DOC>
<DOCNO> 170598 </DOCNO>
The EPR Argument in a Relational Interpretation of Quantum Mechanics


  It is shown that in the Rovelli relational interpretation of quantum
mechanics, in which the notion of absolute or observer independent state is
rejected, the conclusion of the ordinary EPR argument turns out to be
frame-dependent, provided the conditions of the original argument are suitably
adapted to the new interpretation. The consequences of this result for the
`peaceful coexistence' of quantum mechanics and special relativity are briefly
discussed.

</DOC>
<DOC>
<DOCNO> 120706 </DOCNO>
CLASS B0739+366: A new two-image gravitational lens system


  We present the discovery of CLASS B0739+366, a new gravitational lens system
from the Cosmic Lens All-Sky Survey. Radio imaging of the source with the Very
Large Array (VLA) shows two compact components separated by $0\farcs54$, with a
flux density ratio of $\sim$ 6:1. High-resolution follow-up observations using
the Very Long Baseline Array (VLBA) at 1.7 GHz detect weak, parity-reversed jet
emission from each of the radio components. Hubble Space Telescope NICMOS F160W
observations detect infrared counterparts to the lensed images, as well as an
extended object between them which we identify as the lensing galaxy. Redshifts
for the galaxy and lensed source have not yet been obtained. For typical lens
and source redshifts of $z=0.5$ and $z=1.5$, respectively, preliminary mass
modeling predicts a time delay of $\sim7h^{-1}$ days in a flat $\Omega_{M}=1.0$
universe. The small predicted time delay and weak radio components will make
CLASS B0739+366 a challenging target for Hubble constant determination.

</DOC>
<DOC>
<DOCNO> 84133 </DOCNO>
Approximate Analytical Solutions to the Initial Data Problem of Black


  We present approximate analytical solutions to the Hamiltonian and momentum
constraint equations, corresponding to systems composed of two black holes with
arbitrary linear and angular momentum. The analytical nature of these initial
data solutions makes them easier to implement in numerical evolutions than the
traditional numerical approach of solving the elliptic equations derived from
the Einstein constraints. Although in general the problem of setting up initial
conditions for black hole binary simulations is complicated by the presence of
singularities, we show that the methods presented in this work provide initial
data with $l_1$ and $l_\infty$ norms of violation of the constraint equations
falling below those of the truncation error (residual error due to
discretization) present in finite difference codes for the range of grid
resolutions currently used. Thus, these data sets are suitable for use in
evolution codes. Detailed results are presented for the case of a head-on
collision of two equal-mass M black holes with specific angular momentum 0.5M
at an initial separation of 10M. A straightforward superposition method yields
data adequate for resolutions of $h=M/4$, and an "attenuated" superposition
yields data usable to resolutions at least as fine as $h=M/8$. In addition, the
attenuated approximate data may be more tractable in a full (computational)
exact solution to the initial value problem.

</DOC>
<DOC>
<DOCNO> 151172 </DOCNO>
Noncommutative D-Brane in Non-Constant NS-NS B Field Background


  We show that when the field strength H of the NS-NS B field does not vanish,
the coordinates X and momenta P of an open string endpoints satisfy a set of
mixed commutation relations among themselves. Identifying X and P with the
coordinates and derivatives of the D-brane world volume, we find a new type of
noncommutative spaces which is very different from those associated with a
constant B field background.

</DOC>
<DOC>
<DOCNO> 84225 </DOCNO>
A group of invariance transformations for nonrelativistic quantum


  This paper defines, on the Galilean space-time, the group of asymptotically
Euclidean transformations (AET), which are equivalent to Euclidean
transformations at space-time infinity, and proposes a formulation of
nonrelativistic quantum mechanics which is invariant under such
transformations. This formulation is based on the asymptotic quantum measure,
which is shown to be invariant under AET's. This invariance exposes an
important connection between AET's and Feynman path integrals, and reveals the
nonmetric character of the asymptotic quantum measure. The latter feature
becomes even clearer when the theory is formulated in terms of the
coordinate-free formalism of asymptotically Euclidean manifold, which do not
have a metric structure. This mathematical formalism suggests the following
physical interpretation: (i) Particles evolution is represented by trajectories
on an asymptotically Euclidean manifold; (ii) The metric and the law of motion
are not defined a priori as fundamental entities, but they are properties of a
particular class of reference frames; (iii) The universe is considered as a
probability space in which the asymptotic quantum measure plays the role of a
probability measure. Points (ii) and (iii) are used to build the asymptotic
measurement theory, which is shown to be consistent with traditional quantum
measurement theory. The most remarkable feature of this measurement theory is
the possibility of having a nonchaotic distribution of the initial conditions
(NCDIC), an extremely counterintuitive but not paradoxical phenomenon which
allows to interpret typical quantum phenomena, such as particle diffraction and
tunnel effect, while still providing a description of their motion in terms of
classical trajectories.

</DOC>
<DOC>
<DOCNO> 122388 </DOCNO>
Photon Scattering by Relativistic Flows in Schwarzschild Spacetimes. I.


  We study the spectra generated as a result of bulk Comptonization by
relativistic electrons in radial flows onto compact objects. We solve
numerically the general-relativistic radiative transfer equation in the
Schwarzschild spacetime, in steady-state and under minimal assumptions. We show
that power-law spectra result from multiple scatterings, in a way similar to
thermal Comptonization. We also find that photon-electron interactions taking
place near the black-hole event horizon affect very little the emerging
spectra. We, therefore, argue that bulk Comptonization spectra do not carry
distinguishing signatures of the compact object around which they are produced.
We examine the dependence of the spectra on simplifications often employed
regarding the spacetime geometry, the distribution of photon sources, and the
boundary conditions. We show that the existence of trapped characteristics
around a black hole reduces the efficiency of Comptonization and that general
relativistic effects identically cancel bulk Comptonization effects for a
free-falling flow and in the limit of infinitesimal mean-free path. As a
result, we find that neglecting the curved spacetime geometry leads to
overestimating the high-energy flux by up to an order of magnitude. Finally, we
demonstrate that the spectrum from accretion onto a neutron star depends
sensitively on the imposed boundary conditions, while that from a black hole is
immune to such choices.

</DOC>
<DOC>
<DOCNO> 7786 </DOCNO>
Strong vortex pinning in the low-temperature superconducting phase of


  We have found a sharp transition at T_c2=350 mK in the vortex creep rate of a
single crystal of (U_1-xTh_x)Be_13 with T_c=523 mK (x=0.0275). For T<<T_c2, no
creep of vortices is observed in a time scale of 10^5 s, while for T_c2<T<T_c,
vortices creep at very high rates (30 % of decay from a metastable
configuration in the first 10^5 s at T=400 mK). The sharp transition occurs at
the same temperature at which the second jump in the specific heat appears in
these samples. Similar low levels of creep rates have been reported by us in
the low-T superconducting phase of UPt_3.

</DOC>
<DOC>
<DOCNO> 151753 </DOCNO>
Phases of Thermal Super Yang-Mills


  We review the thermodynamics of the confined and unconfined phases of
superconformal Yang-Mills at large N on a three-sphere, focussing especially on
the confinement-deconfinement transition. We determine an N-dependent phase
boundary and point out some directions for future work.

</DOC>
<DOC>
<DOCNO> 178389 </DOCNO>
Solutions of the pion dispersion equation in the medium: new aspects


  In symmetrical nuclear matter the solutions of pion dispersion equation are
investigated in the complex plane of the pion frequency \omega. There are three
well-known branches of solutions on the physical sheet : sound, pion and
isobar, at the matter density less than the critical one \rho <\rho_c. At \rho
>\rho_c the fourth branch appears on the physical sheet. For this branch the
condition \omega^2_c\leq0 (in general case Re\omega^2_c\leq0) takes place. This
points out the instability of the ground state which is possibly related to the
pion condensation.

</DOC>
<DOC>
<DOCNO> 69311 </DOCNO>
Gauge dependence and matching procedure of a nonrelativistic QCD


  We investigate gauge dependence of a nonrelativistic boundstate formalism
used in contemporary calculations. It is known that the effective Hamiltonian
of the boundstate system depends on the choice of gauge. We obtain the gauge
transformation charge of the Hamiltonian, by which gauge independence of the
mass spectrum and gauge dependences of the boundstate wave functions are
dictated. We raise two questions of practical and physical interest, and
provide answers to them.

</DOC>
<DOC>
<DOCNO> 170578 </DOCNO>
Quantum computing via measurements only


  A quantum computer promises efficient processing of certain computational
tasks that are intractable with classical computer technology. While basic
principles of a quantum computer have been demonstrated in the laboratory,
scalability of these systems to a large number of qubits, essential for
practical applications such as the Shor algorithm, represents a formidable
challenge. Most of the current experiments are designed to implement sequences
of highly controlled interactions between selected particles (qubits), thereby
following models of a quantum computer as a (sequential) network of quantum
logic gates. Here we propose a different model of a scalable quantum computer.
In our model, the entire resource for the quantum computation is provided
initially in form of a specific entangled state (a so-called cluster state) of
a large number of qubits. Information is then written onto the cluster,
processed, and read out form the cluster by one-particle measurements only. The
entangled state of the cluster thus serves as a universal substrate for any
quantum computation. Cluster states can be created efficiently in any system
with a quantum Ising-type interaction (at very low temperatures) between
two-state particles in a lattice configuration.

</DOC>
<DOC>
<DOCNO> 39887 </DOCNO>
Polarimetry at a Future Linear Collider - How Precise?


  At a future linear collider, a polarized electron beam will play an important
role in interpreting new physics signals. Backgrounds to a new physics reaction
can be reduced by choice of the electron polarization state. The origin of a
new physics reaction can be clarified by measuring its polarization-dependence.
This paper examines some options for polarimetry with an emphasis on physics
issues that motivate how precise the polarization determination needs to be. In
addition to Compton polarimetry, the possibility of using Standard Model
asymmetries, such as the asymmetry in forward W-pairs, is considered as a
possible polarimeter. Both e+e- and e-e- collider modes are considered.

</DOC>
<DOC>
<DOCNO> 8094 </DOCNO>
Time dependence of evanescent quantum waves


  The time dependence of quantum evanescent waves generated by a point source
with an infinite or a limited frequency band is analyzed. The evanescent wave
is characterized by a forerunner (transient) related to the precise way the
source is switched on. It is followed by an asymptotic, monochromatic wave
which at long times reveals the oscillation frequency of the source. For a
source with a sharp onset the forerunner is exponentially larger than the
monochromatic solution and a transition from the transient regime to the
asymtotic regime occurs only at asymptotically large times. In this case, the
traversal time for tunneling plays already a role only in the transient regime.
To enhance the monochromatic solution compared to the forerunner we investigate
(a) frequency band limited sources and (b) the short time Fourier analysis (the
spectrogram) corresponding to a detector which is frequency band limited.
Neither of these two methods leads to a precise determination of the traversal
time. However, if they are limited to determine the traversal time only with a
precision of the traversal time itself both methods are successful: In this
case the transient behavior of the evanescent waves is at a time of the order
of the traversal time followed by a monochromatic wave which reveals the
frequency of the source.

</DOC>
<DOC>
<DOCNO> 69372 </DOCNO>
Chiral QED out of matter


  In a previous paper we have shown how the Wilsonian renormalization group
naturally leads to the equivalence of the standard QED with a matter-only
theory. In this paper we give an improved explanation of the equivalence and
discuss, as an example, the equivalence of a chiral QED in the Higgs phase with
a matter-only theory. Ignoring the contributions suppressed by the negative
powers of a UV cutoff, the matter-only theory is equivalent to the
perturbatively renormalizable chiral QED with two complex Higgs fields. In the
matter-only theory chiral anomaly arises without elementary gauge fields.

</DOC>
<DOC>
<DOCNO> 102413 </DOCNO>
Gradient corrections for semiclassical theories of atoms in strong


  This paper is divided into two parts. In the first one the von Weizs\"acker
term is introduced to the Magnetic TF theory and the resulting MTFW functional
is mathematically analyzed. In particular, it is shown that the von
Weizs\"acker term produces the Scott correction up to magnetic fields of order
$B \ll Z^2$, in accordance with a result of V. Ivrii on the quantum mechanical
ground state energy. The second part is dedicated to gradient corrections for
semiclassical theories of atoms restricted to electrons in the lowest Landau
band. We consider modifications of the Thomas-Fermi theory for strong magnetic
fields (STF), i.e. for $B \ll Z^3$. The main modification consists in replacing
the integration over the variables perpendicular to the field by an expansion
in angular momentum eigenfunctions in the lowest Landau band. This leads to a
functional (DSTF) depending on a sequence of one-dimensional densities. For a
one-dimensional Fermi gas the analogue of a Weizs\"acker correction has a
negative sign and we discuss the corresponding modification of the DSTF
functional.

</DOC>
<DOC>
<DOCNO> 13077 </DOCNO>
Tuning Fermi-surface properties through quantum confinement in metallic


  We describe a new class of nanoscale structured metals wherein the effects of
quantum confinement are combined with dispersive metallic electronic states to
induce modifications to the fundamental low-energy microscopic properties of a
three-dimensional metal: the density of states, the distribution of Fermi
velocities, and the collective electronic response.

</DOC>
<DOC>
<DOCNO> 40017 </DOCNO>
$\tan\beta$ Determination From Heavy Higgs Boson Production at Linear


  We study the production at future $e^+e^-$ linear colliders of the heavy
neutral Higgs bosons $H$ and $A$ of the minimal supersymmetric standard model
in association with top and bottom quarks. The cross sections have a strong
dependence on the parameter $\tan\beta$, and thus provide a good way to
determine it. At a linear collider with $\sqrt s = 0.5-1$ TeV and expected
integrated luminosities, we find significant sensitivities for determining
$\tan\beta$. In the Supergravity scenario, the sensitivity is particularly
strong for $\tan\beta > 10$, reaching a 15% or better measurement. In the
general MSSM scenario, the interplay between the $4b$ and $4t$ channels results
in a good determination for $\tan\beta < 10$, while the sensitivity is weakened
for higher values of $\tan\beta$.

</DOC>
<DOC>
<DOCNO> 100598 </DOCNO>
On the rigid algebraic structure of Euclidean spaces


  It is shown that the groups of automorphisms of Euclidean spaces are
isomorphic to the groups of topologic automorphisms of respectively factored
arithmetic spaces. In particular, the geometry of Euclidean n-space with
positive signature is associated with factorization of n-dimensional arithmetic
space into n-dimensional sphere.

</DOC>
<DOC>
<DOCNO> 12410 </DOCNO>
Exact Universal Amplitude Ratios for Two-Dimensional Ising Models and a


  We have derived analytic expressions for the amplitudes of correction terms
in the critical free energy and inverse correlation length expansions for
square, honeycomb, and plane-triangular lattices in strip geometry. We have
found that ratio of amplitudes for all of these lattices is universal. We have
also obtained similar expansions for the ground state energy and the first
energy gap of a critical quantum spin chain and find that the amplitude ratios
have the same values.

</DOC>
<DOC>
<DOCNO> 40062 </DOCNO>
Finding Z' bosons coupled preferentially to the third family at CERN LEP


  Z' bosons that couple preferentially to the third generation fermions can
arise in models with extended weak (SU(2)xSU(2)) or hypercharge (U(1)xU(1))
gauge groups. We show that existing limits on quark-lepton compositeness set by
the LEP and Tevatron experiments translate into lower bounds of order a few
hundred GeV on the masses of these Z' bosons. Resonances of this mass can be
directly produced at the Tevatron. Accordingly, we explore in detail the limits
that can be set at Run II using the process p pbar -> Z' -> tau tau -> e mu. We
also comment on the possibility of using hadronically-decaying taus to improve
the limits.

</DOC>
<DOC>
<DOCNO> 71491 </DOCNO>
Higgs, SUSY and the Standard Model at $\gamma\gamma$ Colliders


  In this report I surveyed physics potential of the gamma-gamma option of a
Linear e+e- Collider with the following questions in mind: What new discovery
can be expected at a gamma-gamma collider in addition to what will be learned
at its `parent' e+e- Linear Collider? By taking account of the hard energy
spectrum and polarization of colliding photons, produced by Compton
back-scattering of laser light off incoming e- beams, we find that a
gamma-gamma collider is most powerful when new physics appears in the neutral
spin-zero channel at an invariant mass below about 80% of the c.m. energy of
the colliding e-e- system. If a light Higgs boson exists, its properties can be
studied in detail, and if its heavier partners or a heavy Higgs boson exists in
the above mass range, they may be discovered at a gamma-gamma collider. CP
property of the scalar sector can be explored in detail by making use of linear
polarization of the colliding photons, decay angular correlations of final
state particles, and the pattern of interference with the Standard model
amplitudes. A few comments are given for SUSY particle studies at a gamma-gamma
collider, where a pair of charged spinless particles is produced in the s-wave
near the threshold. Squark-onium may be discovered. An e^\pm gamma collision
mode may measure the Higgs-Z-gamma coupling accurately and probe flavor
oscillations in the slepton sector. As a general remark, all the Standard Model
background simulation tools should be prepared in the helicity amplitude level,
so that simulation can be performed for an arbitrary set of Stokes parameters
of the incoming photon beams.

</DOC>
<DOC>
<DOCNO> 101398 </DOCNO>
Stable Equivalence of Knots on Surfaces and Virtual Knot Cobordisms


  We introduce an equivalence relation, called stable equivalence, on knot
diagrams and closed curves on surfaces. We give bijections between the set of
abstract knots, the set of virtual knots, and the set of the stable equivalence
classes of knot diagrams on surfaces. Using these bijections, we define
concordance and link homology for virtual links. As an application, it is shown
that Kauffman's example of a virtual knot diagram is not equivalent to a
classical knot diagram.

</DOC>
<DOC>
<DOCNO> 119236 </DOCNO>
Formation of binary millisecond pulsars with relatively high surface


  We have carried out numerical evolutionary calculations of binary systems to
investigate the formation of binary millisecond pulsars (pulsars with white
dwarf companions). We apply the ``standard scenario'' in which the binary
pulsars are formed from low-mass and intermediate-mass X-ray binaries as well
the alternative scenario in which the neutron stars are formed by
accretion-induced collapse (AIC) of white dwarfs. The mass transfer processes
are carefully followed by taking into account a number of binary interactions.
Assuming that the magnetic fields of the neutron stars decay due to the
accretion, we calculate the pulsar surface dipole magnetic field strength at
the end of the mass transfer as a function of the final orbital period. We find
that while the observed data of the majority of pulsars are compatible with the
derived relations, we fail to produce binary pulsars with relatively high
magnetic fields and short orbital periods (such as PSR B0655+64). We conclude
that those systems are most likely formed through common-envelope phase.

</DOC>
<DOC>
<DOCNO> 102273 </DOCNO>
Some examples related to the Deligne-Simpson problem


  We consider the variety of $(p+1)$-tuples of matrices $M_j$ from given
conjugacy classes from $GL(n,{\bf C})$ such that $M_1... M_{p+1}=I$. This
variety is connected with the Deligne-Simpson problem and the matrices $M_j$
are interpreted as monodromy operators of regular systems on Riemann's sphere.
We consider among others cases when the dimension of the variety is higher than
the expected one due to the presence of $(p+1)$-tuples with non-trivial
centralizers.

</DOC>
<DOC>
<DOCNO> 122381 </DOCNO>
The brightness of SN 1991T and the uniformity of decline-rate and colour


  We present a distance to NGC 4527, the host galaxy of the type Ia SN 1991T,
measured by surface brightness fluctuations. This supernova has been labelled
``peculiar'' both on the grounds of its spectroscopic behaviour and its
apparent overluminosity with respect to other supernovae. The distance modulus
to NGC 4527 and thus to SN 1991T is 30.26+-0.09. This relatively short distance
largely removes the discrepancy with other Ia supernovae having similar
light-curve characteristics and also removes the motivation for interpreting SN
1991T as a super-Chandrasekhar explosion. However, the reddening uncertainty
results in significant uncertainty of the absolute magnitudes.

</DOC>
<DOC>
<DOCNO> 9947 </DOCNO>
Topology of evolving networks: local events and universality


  Networks grow and evolve by local events, such as the addition of new nodes
and links, or rewiring of links from one node to another. We show that
depending on the frequency of these processes two topologically different
networks can emerge, the connectivity distribution following either a
generalized power-law or an exponential. We propose a continuum theory that
predicts these two regimes as well as the scaling function and the exponents,
in good agreement with the numerical results. Finally, we use the obtained
predictions to fit the connectivity distribution of the network describing the
professional links between movie actors.

</DOC>
<DOC>
<DOCNO> 12517 </DOCNO>
Smearing of Coulomb Blockade by Resonant Tunneling


  We study the Coulomb blockade in a grain coupled to a lead via a resonant
impurity level. We show that the strong energy dependence of the transmission
coefficient through the impurity level can have a dramatic effect on the
quantization of the grain charge. In particular, if the resonance is
sufficiently narrow, the Coulomb staircase shows very sharp steps even if the
transmission through the impurity at the Fermi energy is perfect. This is in
contrast to the naive expectation that perfect transmission should completely
smear charging effects.

</DOC>
<DOC>
<DOCNO> 99596 </DOCNO>
On the K-property of quantized Arnold cat maps


  We prove that some quantized Arnold cat maps are entropic K-systems. This
result was formulated by H. Narnhofer[1], but the fact that the optimal
decomposition for the multi-channel entropy constructed there is not strictly
local was not appropriately taken care of. We propose a strictly local
decomposition based on a construction of Voiculescu.

</DOC>
<DOC>
<DOCNO> 12896 </DOCNO>
Correlated versus Uncorrelated Stripe Pinning: the Roles of Nd and Zn


  We investigate the stripe pinning produced by Nd and Zn co-dopants in
cuprates via a renormalization group approach. The two dopants play
fundamentally different roles in the pinning process. While Nd induces a
correlated pinning potential that traps the stripes in a flat phase and
suppresses fluctuations, Zn pins the stripes in a disordered manner and
promotes line meandering. We obtain the zero temperature phase diagram and
compare our results with neutron scattering data. A good agreement is found
between theory and experiment.

</DOC>
<DOC>
<DOCNO> 9496 </DOCNO>
Thermodynamics' 0-th-Law in a nonextensive scenario


  Tsallis' thermostatistics is by now recognized as a new paradigm for
statistical mechanical considerations. However, it is still affected by a
serious hindrance: the generalization of thermodynamics' zero-th law to a
nonextensive scenario is plagued by difficulties. Here we show how to overcome
this problem.

</DOC>
<DOC>
<DOCNO> 150954 </DOCNO>
Irreducible antifield formalism for reducible constrained Hamiltonian


  Reducible constrained Hamiltonian systems are quantized accordingly an
irreducible BRST manner. Our procedure is based on the construction of an
irreducible theory which is physically equivalent with the original one. The
equivalence between the two systems makes legitimate the substitution of the
BRST quantization for the reducible theory by that of the irreducible system.
The general formalism is illustrated in detail on a model involving abelian
one- and two-form gauge fields.

</DOC>
<DOC>
<DOCNO> 69437 </DOCNO>
Symmetries and Symmetry Breaking


  Several new proton-proton parity violation experiments are presently either
being performed or are being prepared for execution in the near future.
Similarly, a new measurement of the parity-violating gamma-ray asymmetry in
polarized neutron capture on the proton is being developed with a ten-fold
improvement over previous measurements. These experiments are intended to
provide stringent constraints on the set of seven effective weak meson-nucleon
coupling constants. Time-reversal-invariance non-conservation has now been
unequivocally demonstrated in a direct measurement at CPLEAR. Tests may also be
made of time-reversal-invariance non-conservation in systems other than the
kaon system. There exist two classes of time-reversal invariance breaking
interactions: P-odd/T-odd and P-even/T-odd interactions. Constraints on the
first ones stem from measurements of the electric dipole moment of the neutron,
while constraints on the second ones stem from the same and measurements of
charge symmetry breaking in neutron-proton elastic scattering and from $K$
semi-leptonic decays. A series of precision experiments, either ongoing or
being prepared, will determine the neutral weak current of the proton by
measuring the parity-violating normalized asymmetry in electron-proton elastic
scattering. A direct comparison between the electromagnetic and neutral weak
ground state currents of the nucleon will allow a delineation of the
contributions to these currents of the various quark flavours, including quarks
which belong exclusively to the nucleon sea. An extension of these precision
experiments to very low momentum transfer would permit stringent limits to be
placed on physics beyond the standard model.

</DOC>
<DOC>
<DOCNO> 8001 </DOCNO>
Exact Potts Model Partition Functions on Ladder Graphs


  We present exact calculations of the partition function $Z$ of the $q$-state
Potts model and its generalization to real $q$, the random cluster model, for
arbitrary temperature on $n$-vertex ladder graphs with free, cyclic, and
M\"obius longitudinal boundary conditions. These partition functions are
equivalent to Tutte/Whitney polynomials for these graphs. The free energy is
calculated exactly for the infinite-length limit of these ladder graphs and the
thermodynamics is discussed.

</DOC>
<DOC>
<DOCNO> 100674 </DOCNO>
Flat Lorentz 3-Manifolds and Cocompact Fuchsian Groups


  This paper gives a new proof of a result of Geoff Mess that the linear
holonomy group of a complete flat Lorentz 3-manifold cannot be cocompact in
SO(2,1). The proof uses a signed marked Lorentzian length-spectrum invariant
developed by G.Margulis, reinterpreted in terms of deformations of hyperbolic
surfaces.

</DOC>
<DOC>
<DOCNO> 13663 </DOCNO>
Stochastics theory of log-periodic patterns


  We introduce an analytical model based on birth-death clustering processes to
help understanding the empirical log-periodic corrections to power-law scaling
and the finite-time singularity as reported in several domains including
rupture, earthquakes, world population and financial systems. In our
stochastics theory log-periodicities are a consequence of transient clusters
induced by an entropy-like term that may reflect the amount of cooperative
information carried by the state of a large system of different species. The
clustering completion rates for the system are assumed to be given by a simple
linear death process. The singularity at t_{o} is derived in terms of
birth-death clustering coefficients.

</DOC>
<DOC>
<DOCNO> 71129 </DOCNO>
Implications of the ALEPH tau-Lepton Decay Data for Perturbative and


  We use ALEPH data on hadronic $\tau$ decays in order to calculate Euclidean
coordinate space correlation functions in the vector and axial-vector channels.
The linear combination $V-A$ receives no perturbative contribution and is
quantitatively reproduced by the instanton liquid model. In the case of $V+A$
the instanton calculation is in good agreement with the data once perturbative
corrections are included. These corrections clearly show the evolution of
$\alpha_s$. We also analyze the range of validity of the Operator Product
Expansion (OPE). In the $V-A$ channel we find a dimension $d=6$ contribution
which is comparable to the original SVZ estimate, but the instanton model
provides a different non-singular term of the same magnitude. In the $V+A$ case
both the OPE and the instanton model predict the same $d=4$ power correction
induced by the gluon condensate, but it is masked by much larger perturbative
contributions. We conclude that the range of validity of the OPE is limited to
$x\lsim0.3$ fm, whereas the instanton model describes the data over the entire
range.

</DOC>
<DOC>
<DOCNO> 152022 </DOCNO>
Bound state problem for a Dirac particle in an external static charge


  We study the self-interaction effects for the Dirac particle moving in an
external field created by static charges in (1+1)-dimensions. Assuming that the
total electric charge of the system vanishes, we show that the asymptotically
linearly rising part of the external potential responsible for nonexistence of
bound states in the external field problem without self-interaction is
cancelled by the self-potential of the zero mode of the Dirac particle charge
density. We derive the Dirac equation which includes the self-potential of the
non-zero modes and is nonlinear. We solve the spectrum problem in the case of
two external positive charges of the same value and prove that the Dirac
particle and external charges are confined in a stable system.

</DOC>
<DOC>
<DOCNO> 101287 </DOCNO>
Uniform asymptotic estimates of transition probabilities on combs


  We investigate the asymptotical behaviour of the transition probabilities of
the simple random walk on the 2-comb. In particular we obtain space-time
uniform asymptotical estimates which show the lack of symmetry of this walk
better than local limit estimates. Our results also point out the impossibility
of getting Jones-type non-Gaussian estimates.

</DOC>
<DOC>
<DOCNO> 101268 </DOCNO>
Nonlocal Mathematics


  This is a research announcement on what is best termed `nonlocal' methods in
mathematics. (This is not to be confused with global analysis.) The nonlocal
formulation of physics in \cite{principia} points to a fresh viewpoint in
mathematics: Nonlocal viewpoint. It involves analyzing objects of geometry and
analysis using nonlocal methods, as opposed to the classical local methods,
e.g., Newton's calculus. It also involves analyzing new nonlocal geometries and
nonlocal analytical objects, i.e. nonlocal fields. In geometry, we introduce
and study (nonlocal) forms, differentials, integrals, connections, curvatures,
holonomy, G-structures, etc. In analysis, we analyze local fields using
nonlocal methods (semilocal analysis); nonlocal fields nonlocally (of course);
and the connection between nonlocal linear analysis and local nonlinear
analysis. Analysis and geometry are next synthesized to yield nonlocal (hence
noncommutative) homology, cohomology, de Rham theory, Hodge theory, Chern-Weil
theory, K-theory (called N-theory) and index theory. Applications include
theorems such as nonlocal-noncommutative Riemann-Roch, Gauss-Bonnet, Hirzebruch
signature, etc. The nonlocal viewpoint is also investigated in algebraic
geometry, analytic geometry, and, to some extent, in arithmetic geometry,
resulting in powerful bridges between the classical and nonlocal-noncommutative
aspects.

</DOC>
<DOC>
<DOCNO> 68185 </DOCNO>
Unusual bound states of quark matter within the NJL model


  Properties of dense quark matter in and out of chemical equilibrium are
studied within the SU(3) Nambu-Jona-Lasinio model. In addition to the 4-fermion
scalar and vector terms the model includes also the 6-fermion flavour mixing
interaction. First we study a novel form of deconfined matter, meso-matter,
which is composed of equal number of quarks and antiquarks. It can be thought
of as a strongly compressed meson gas where mesons are melted into their
elementary constituents, quarks and antiquarks. Strongly bound states in this
quark-antiquark matter are predicted for all flavour combinations of
quark-antiquark pairs. The maximum binding energy reaches up to 180 MeV per
pair for mixtures with about 70% of strange quark-antiquark pairs. Equilibrated
baryon-rich quark matter with various flavour compositions is also studied. In
this case only shallow bound states appear in systems with a significant
admixture (about 40%) of strange quarks (strangelets). Their binding energies
are quite sensitive to the relative strengths of scalar and vector
interactions. The common property of all these bound states is that they appear
at high particle densities when the chiral symmetry is nearly restored. Thermal
properties of meso-matter as well as chemically equilibrated strange quark
matter are also investigated. Possible decay modes of these bound states are
discussed.

</DOC>
<DOC>
<DOCNO> 70370 </DOCNO>
Soft Gluon Resummation for Polarized Deep-inelastic Production of Heavy


  We present the threshold resummation for the cross section of heavy quark
production in polarized deep-inelastic scattering to next-to-leading
logarithmic accuracy and in single-particle inclusive kinematics. We expand our
resummed result in alpha_s to next-to-leading and next-to-next-to-leading order
and study the impact of these higher order corrections on the charm structure
function g_1 in the kinematical range accessible to the HERMES and COMPASS
experiments.

</DOC>
<DOC>
<DOCNO> 10112 </DOCNO>
Charge occupancy of two interacting electrons on artificial molecules -


  We present exact solutions for two interacting electrons on an artificial
atom and on an artificial molecule made by one and two (single level) quantum
dots connected by ideal leads. Specifically, we calculate the accumulated
charge on the dots as function of the gate voltage, for various strengths of
the electron-electron interaction and of the hybridization between the dots and
the (one-dimensional) leads. With increasing of the (negative) gate voltage,
the accumulated charge in the two-electron ground state increases in gradual
steps from 0 to 1 and then to 2. The value 0 represents an "insulating" state,
where both electrons are bound to shallow states on the impurities. The value
of 1 corresponds to a "metal", with one electron localized on the dots and the
other extended on the leads. The value of 2 corresponds to another "insulator",
with both electrons strongly localized. The width of the "metallic" regime
diverges with strength of the electron-electron interaction for the single dot,
but remains very narrow for the double dot. These results are contrasted with
the simple Coulomb blockade picture.

</DOC>
<DOC>
<DOCNO> 67828 </DOCNO>
Relativistic Charge Form Factor of the Deuteron from (np)-Scattering


  Relativistic integral representation in terms of experimental neutron-proton
scattering phase shifts is used to compute the charge form factor of the
deuteron $ G_{Cd}(Q^2)$. The results of numerical calculations of
$|G_{Cd}(Q^2)|$ are presented in the interval of the four-momentum transfers
squared $0 \leq Q^2 \leq 35 fm^{-2}$. Zero and the prominent secondary maximum
in $|G_{Cd}(Q^2)|$ are the direct consequences of the change of sign in the
experimental $^3S_1 $- phase shifts. Till the point $Q^2 \simeq 20 fm^{-2}$ the
calculated total relativistic correction to $|G_{Cd}(Q^2)|$ is positive and
reaches the maximal value of 25% at $Q^2 \simeq 14 fm^{-2}$.

</DOC>
<DOC>
<DOCNO> 99830 </DOCNO>
Gauss Sums and Quantum Mechanics


  By adapting Feynman's sum over paths method to a quantum mechanical system
whose phase space is a torus, a new proof of the Landsberg-Schaar identity for
quadratic Gauss sums is given. In contrast to existing non-elementary proofs,
which use infinite sums and a limiting process or contour integration, only
finite sums are involved. The toroidal nature of the classical phase space
leads to discrete position and momentum, and hence discrete time. The
corresponding `path integrals' are finite sums whose normalisations are derived
and which are shown to intertwine cyclicity and discreteness to give a finite
version of Kelvin's method of images.

</DOC>
<DOC>
<DOCNO> 40206 </DOCNO>
A measurement of the charged and neutral B meson lifetimes using fully


  Data collected with the BABAR detector at the PEP-II asymmetric B Factory at
SLAC are used to study the lifetimes of the B^0 and B^+ mesons. The data sample
consists of 7.4 fb-1 collected near the Y(4S) resonance. B^0 and B^+ mesons are
fully reconstructed in several exclusive hadronic decay modes to charm and
charmonium final states. The B lifetimes are determined from the flight length
difference between the two B mesons which are pair-produced in the Y(4S) decay.
The preliminary measurements of the lifetimes are tau_B0 =
1.506+/-0.052(stat)+/-0.029(syst) ps, tau_B+ =
1.602+/-0.049(stat)+/-0.035(syst) ps, and of their ratio is tau_B+/tau_B0 =
1.065+/-0.044(stat)+/-0.021(syst).

</DOC>
<DOC>
<DOCNO> 80585 </DOCNO>
The Intrinsic Coupling in Integrable Quantum Field Theories


  The intrinsic 4-point coupling, defined in terms of a truncated 4-point
function at zero momentum, provides a well-established measure for the
interaction strength of a QFT. We show that this coupling can be computed
non-perturbatively and to high accuracy from the form factors of an
(integrable) QFT. The technique is illustrated and tested with the Ising model,
the XY-model and the O(3) nonlinear sigma-model. The results are compared to
those from high precision lattice simulations.

</DOC>
<DOC>
<DOCNO> 69999 </DOCNO>
On the use of the reciprocal basis in neutral meson mixing


  In the presence of CP violation, the effective Hamiltonian matrix describing
a neutral meson anti-meson system does not commute with its hermitian
conjugate. As a result, this matrix cannot be diagonalized by a unitary
transformation and one needs to introduce a reciprocal basis. Although known,
this fact is seldom discussed and almost never used. Here, we use this concept
to highlight a parametrization of the Hamiltonian matrix in terms of physical
observables, and we show that using it reduces a number of long and tedious
derivations into simple matrix multiplications. These results have a
straightforward application for propagation in matter. We also comment on the
(mathematical) relation with neutrino oscillations.

</DOC>
<DOC>
<DOCNO> 152052 </DOCNO>
Renormalisation group flows of boundary theories


  We review recent developments in the theory of renormalisation group flows in
minimal models with boundaries. Among these, we discuss in particular the
perturbative calculations of Recknagel et al, not only as a tool to predict the
IR endpoints of certain flows, but also as a motivation for considering the
particular limiting case of c = 1. By treating this limit, we are able to
investigate a wide class of perturbations by considering them as deformations
away from the c = 1 point. We also present the truncated conformal space
approach as a tool for investigating the space of RG flows and checking
particular predictions.

</DOC>
<DOC>
<DOCNO> 68843 </DOCNO>
Fat penguins and imaginary penguins in perturbative QCD


  We evaluate $B\to K\pi$ decay amplitudes in perturbative QCD picture. It is
found that penguin contributions are dynamically enhanced by nearly 50%
compared to those assumed in the factorization approximation. It is also shown
that annihilation diagrams are not negligible, and give large strong phases.
Our results for branching ratios of $B\to K\pi$ decays for a representative
parameter set are consistent with data. We evaluate $B\to K\pi$ decay
amplitudes in perturbative QCD picture. It is found that penguin contributions
are dynamically enhanced by nearly 50% compared to those assumed in the
factorization approximation. It is also shown that annihilation diagrams are
not negligible, and give large strong phases. Our results for branching ratios
of $B\to K\pi$ decays for a representative parameter set are consistent with
data.

</DOC>
<DOC>
<DOCNO> 71972 </DOCNO>
Charge asymmetry of pions in the process $e^-e^+\to e^-e^+\pi^+\pi^-$


  The study of the charge asymmetry of produced particles allows to investigate
the interference of different production mechanisms and to determine new
features of the corresponding amplitudes. In the process $e^- e^+ \to e^- e^+
\pi^+ \pi^-$ the two-pion system is produced via two mechanisms: two-photon
(C-even state) and bremsstrahlung (C-odd state) production. We study the charge
asymmetry of pions in a differential in the pion momenta cross section
originating from an interference between these two mechanisms. At low effective
mass of dipions this asymmetry is directly related to the s- and p-phases of
elastic $\pi\pi$ scattering. At higher energies it can give new information
about the $f_0$ meson family, $f_2(1270)$ meson, etc. The asymmetry is
expressed via the pion form factor $F_\pi$ and helicity amplitudes $M_{ab}$ for
the subprocess $\gamma^*\gamma\to \pi^+\pi^-$ as $\sum G_{ab}{\rm
Re}(F_\pi^*M_{ab})$ where we have calculated analytically the coefficients
$G_{ab}$ for the region giving the main contribution to the effect. Several
distributions of pions are presented performing a numerical analysis in a model
with point-like pions. In the region near the dipion threshold the asymmetry is
of the order of 1%. We show that with suitable cuts the signal to background
ratio can be increased up to about 10%.

</DOC>
<DOC>
<DOCNO> 117016 </DOCNO>
Entropy Shows that Global Warming Should Cause Increased Variability in


  Elementary physical reasoning seems to leave it inevitable that global
warming would increase the variability of the weather. The first two terms in
an approximation to the global entropy are used to show that global warming has
increased the free energy available to drive the weather, and that the variance
of the weather should increase correspondingly.

</DOC>
<DOC>
<DOCNO> 120102 </DOCNO>
Cooling sequences and color-magnitude diagrams for cool white dwarfs


  We present new cooling sequences, color-magnitude diagrams, and color-color
diagrams for cool white dwarfs with pure hydrogen atmospheres down to an
effective temperature $\te=1500$ K. We include a more detailed treatment of the
physics of the fully-ionized interior, particularly an improved discussion of
the thermodynamics of the temperature-dependent ion-ion and ion-electron
contributions of the quantum, relativistic electron-ion plasma. The present
calculations also incorporate accurate boundary conditions between the
degenerate core and the outermost layers as well as updated atmosphere models
including the H$_2$-H$_2$ induced-dipole absorption. We examine the differences
on the cooling time of the star arising from uncertainties in the initial
carbon-oxygen profile and the core-envelope $L$-$T_c$ relation. The maximum
time delay due to crystallization-induced chemical fractionation remains
substantial, from $\sim 1.0$ Gyr for 0.5 and 1.2 $\msol$ white dwarfs to $\sim
1.5$ Gyr for 0.6 to 0.8 $\msol$ white dwarfs, even with initial stratified
composition profiles, and cannot be ignored in detailed white dwarf cooling
calculations. These cooling sequences provide theoretical support to search for
or identify old disk or halo hydrogen-rich white dwarfs by characterizing their
mass and age from their observational signatures.

</DOC>
<DOC>
<DOCNO> 117704 </DOCNO>
HST Observations of M Subdwarfs


  We present the results of an HST snapshot program to search for very-low-mass
stellar companions to nearby M subdwarfs. None of our nine targetted metal-poor
primaries have companions more massive than the hydrogen burning limit,
implying that the halo binary fraction is equal to or less than the Galactic
disk binary fraction below 0.3 M_sun. In addition, the more distant tertiary
VB12, an sdM3.0 companion to an F subdwarf double, is also unresolved. We show
that the relation between WFPC2 F555W and F850LP photometry and ground V,I
photometry is consistent with theoretical expectations. We also report that two
recently observed Hyades M dwarfs appear single.

</DOC>
<DOC>
<DOCNO> 178997 </DOCNO>
Neutrinoless double beta decay within Self-consistent Renormalized


  The first, to our knowledge, calculation of neutrinoless double beta decay
($0\nu\beta\beta$-decay) matrix elements within the self-consistent
renormalised Quasiparticle Random Phase Approximation (SRQRPA) is presented.
The contribution from the momentum-dependent induced nucleon currents to
$0\nu\beta\beta$-decay amplitude is taken into account. A detailed nuclear
structure study includes the discussion of the sensitivity of the obtained
SRQRPA results for $0\nu\beta\beta$-decay of $^{76}$Ge to the parameters of
nuclear Hamiltonian, two-nucleon short-range correlations and the truncation of
the model space. A comparision with the standard and renormalized QRPA is
presented. We have found a considerable reduction of the SRQRPA nuclear matrix
elements, resulting in less stringent limits for the effective neutrino mass.

</DOC>
<DOC>
<DOCNO> 170742 </DOCNO>
Quantum optical weak measurements can visualize photon dynamics in real


  An experiment is proposed to visualize stroboscopically in real time the
dynamics of a photon oscillating between two cavities. The visualization is
implemented by a sequence of weak measurements (POVM), which are carried out by
probing one of the cavities with a Rydberg atom and detecting a resulting phase
shift by Ramsey interferometry. This way to measure the number of photons in a
cavity was experimentally realized by Brune et al.. We suggest a feedback
mechanism which minimizes the disturbance due to the measurement and enables a
detection of the original evolution of the radiation field. PACS numbers:
03.65.Ta, 32.80.-t, 03.67.-a

</DOC>
<DOC>
<DOCNO> 8017 </DOCNO>
Quantum Monte Carlo Methods in Statistical Mechanics


  This paper deals with the optimization of trial states for the computation of
dominant eigenvalues of operators and very large matrices. In addition to
preliminary results for the energy spectrum of van der Waals clusters, we
review results of the application of this method to the computation of
relaxation times of independent relaxation modes at the Ising critical point in
two dimensions.

</DOC>
<DOC>
<DOCNO> 10264 </DOCNO>
An exact-diagonalization study of rare events in disordered conductors


  We determine the statistical properties of wave functions in disordered
quantum systems by exact diagonalization of one-, two- and quasi-one
dimensional tight-binding Hamiltonians. In the quasi-one dimensional case we
find that the tails of the distribution of wave-function amplitudes are
described by the non-linear sigma-model. In two dimensions, the tails of the
distribution function are consistent with a recent prediction based on a direct
optimal fluctuation method.

</DOC>
<DOC>
<DOCNO> 7844 </DOCNO>
Fluid-solid phase-separation in hard-sphere mixtures is unrelated to


  In a recent letter, Buhot proposes that entropy driven phase-separation in
hard-core binary mixtures is directly related to a bond-percolation transition.
However, at least for binary hard-sphere mixtures, calculations based on an
accurate approximation to g_{ll}(r) demonstrate that n_b varies widely along
the phase-boundaries calculated directly by simulations, implying that
bond-percolation is unrelated to the phase-separation in these systems.

</DOC>
<DOC>
<DOCNO> 100830 </DOCNO>
Point-invariant classes of the third order ordinary differential


  Point transformations of the 3-rd order ordinary differential equations are
considered. Special classes of ordinary differential equations that are
invariant under the general point transformations are constructed.

</DOC>
<DOC>
<DOCNO> 119738 </DOCNO>
Weak lensing surveys and the intrinsic correlation of galaxy


  We explore the possibility that an intrinsic correlation between galaxy
ellipticities arising during the galaxy formation process may account for part
of the shear signal recently reported by several groups engaged in weak lensing
surveys. Using high resolution N-body simulations we measure the projected
ellipticities of dark matter halos and their correlations as a function of pair
separation. With this simplifying, but not necessarily realistic assumption
(halo shapes as a proxy for galaxy shapes), we find a positive detection of
correlations up to scales of at least 20 h^-1mpc (limited by the box size). The
signal is not strongly affected by variations in the halo finding technique, or
by the resolution of the simulations. We translate our 3d results into angular
measurements of ellipticity correlation functions and shear variance which can
be directly compared to observations. We also measure similar results from
simulated angular surveys made by projecting our simulation boxes onto the
plane of the sky and applying a radial selection function. Interestingly, the
shear variance we measure is a small, but not entirely negligible fraction
(from ~10-20 %) of that seen by the observational groups, and the ellipticity
correlation functions approximately mimic the functional form expected to be
caused by weak lensing. The amplitude depends on the width in redshift of the
galaxy distribution. If photometric redshifts are used to pick out a screen of
background galaxies with a small width, then the intrinsic correlation may
become comparable to the weak lensing signal. Although we are dealing with
simulated dark matter halos, whether there is a signal from real galaxies could
be checked with a nearby sample with known redshifts.

</DOC>
<DOC>
<DOCNO> 84831 </DOCNO>
A spin foam model without bubble divergences


  We present a spin foam model in which the fundamental ``bubble amplitudes''
(the analog of the one-loop corrections in quantum field theory) are finite as
the cutoff is removed. The model is a natural variant of the field theoretical
formulation of the Barrett-Crane model. As the last, the model is a quantum BF
theory plus an implementation of the constraint that reduces BF theory to
general relativity. We prove that the fundamental bubble amplitudes are finite
by constructing an upper bound, using certain inequalities satisfied by the
Wigner (3n)j-symbols, which we derive in the paper. Finally, we present
arguments in support of the conjecture that the bubble diagrams of the model
are finite at all orders.

</DOC>
<DOC>
<DOCNO> 151163 </DOCNO>
Zhu's Theorem and an algebraic characterization of conformal blocks


  Working in the axiomatic framework recently proposed by Gaberdiel and
Goddard, we prove a generalized version of Zhu's Theorem; for any chiral
bosonic conformal field theory on the sphere, our result characterizes the
chiral blocks in terms of a certain quotient of the Fock space. We also
establish, under a finiteness hypothesis closely related to rationality of the
theory, that the relevant Knizhnik-Zamolodchikov-type equation admits
solutions.

</DOC>
<DOC>
<DOCNO> 121218 </DOCNO>
Broad-band X-ray spectra of the persistent black hole candidates LMC X-1


  We report on observations of the two persistent black hole candidates LMC X-3
and LMCX-1 performed with \BS in October 1997. The flux of LMC X-1 was possibly
measured up to 60 keV, but there is a possible confusion with PSR 0540-69. Fits
with an absorbed multicolor disk black body are not satisfactory, while the
superposition of this model with a power law is acceptable. The sources showed
little variations during the observations. However in LMC X-1 some X-ray color
dependence on intensity is apparent, indicating a hardening of the spectrum in
the second half of the observation. The inner disk radius and temperature
change, featuring the same (anti)correlation found in {\it RXTE} data (Wilms et
al. 2000). QPOs were searched for. In LMC X-3 none was detected; in LMCX-1 a 3
sigma upper (9% rms) limit is given at 0.07 Hz, the frequency of the QPO
discovered with Ginga.

</DOC>
<DOC>
<DOCNO> 119725 </DOCNO>
HI Observations of the starburst galaxy NGC 2146


  NGC 2146 is a peculiar spiral galaxy which is currently undergoing a major
burst of star formation and is immersed in a extended HI structure that has
morphological and kinematical resemblence to a strong tidal interaction. This
paper reports aperture synthesis observations carried out in the 21cm line with
the Very Large Array (VLA - The National Radio Astronomy Observatory (NRAO) is
operated by Associated Universities, Inc. under cooperative agreement with the
National Science Foundation.) of two fields positioned to optimally cover the
HI streams to the north and south of the galaxy, along with a 300 ft total
power spectral mapping program to recover the low surface brightness extended
emission. The observations reveal elongated streams of neutral hydrogen towards
both the north and the south of the optical galaxy extending out up to 6
Holmberg radii. The streams are not in the principle plane of rotation of the
galaxy, but instead are suggestive of a tidal interaction between NGC 2146 and
a LSB companion that was destroyed by the encounter and remains undetected at
optical wavelengths. Part of the southern stream is turning back to fall into
the main galaxy, where it will create a long-lived warp in the HI disk of NGC
2146. Analysis of the trajectory of the outlying gas suggests that the closest
encounter took place about 0.8 billion years ago and that infall of debris will
continue for a similar time span.

</DOC>
<DOC>
<DOCNO> 85418 </DOCNO>
New Five Dimensional Black Holes Classified by Horizon Geometry, and a


  We introduce two new families of solutions to the vacuum Einstein equations
with negative cosmological constant in 5 dimensions. These solutions are static
black holes whose horizons are modelled on the 3-geometries nilgeometry and
solvegeometry. Thus the horizons (and the exterior spacetimes) can be foliated
by compact 3-manifolds that are neither spherical, toroidal, hyperbolic, nor
product manifolds, and therefore are of a topological type not previously
encountered in black hole solutions. As an application, we use the
solvegeometry solutions to construct Bianchi VI$_{-1}$ braneworld cosmologies.

</DOC>
<DOC>
<DOCNO> 150666 </DOCNO>
Three dimensional Conformal Field Theories from Sasakian seven-manifolds


  We present the construction of the candidate conformal field theories dual to
$AdS_4$ non-maximally supersymmetric compactifications of 11D supergravity. We
compare the spectra of the two theories and discuss the realization of the
baryonic symmetries. Finally we comment on the presence in the spectrum of long
multiplets with rational energies, trying to explain their existence.

</DOC>
<DOC>
<DOCNO> 84952 </DOCNO>
Tunneling of the Closed Friedmann Universe with Generation of Scalar


  The evolution of the closed Friedmann Universe with a packet of short scalar
waves is considered with the help of the Wheeler--DeWitt equation. The packet
ensures conservation of homogeneity and isotropy of the metric on average. It
is shown that during tunneling the amplitudes of short waves of a scalar field
can increase catastrophically promptly if their influence to the metric do not
take into account. This effect is similar to the Rubakov-effect of catastrophic
particle creation calculated already in 1984.
  In our approach to the problem it is possible to consider self-consistent
dynamics of the expansion of the Universe and amplification of short waves.
 It results in a decrease of the barrier and interruption of amplification of
waves, and we get an exit of the wave function from the quantum to the
classically available region.

</DOC>
<DOC>
<DOCNO> 72044 </DOCNO>
Systematics of one-loop Yang-Mills diagrams from bosonic string


  We present a general algorithm to compute off-shell, one-loop multigluon
Green functions using bosonic string amplitudes. We identify and parametrize
the regions in the space of moduli of one-loop Riemann surfaces that contribute
to the field theory limit of string amplitudes. Each of these regions can be
precisely associated with a Feynman-like scalar graph with cubic and quartic
vertices, whose lines represent the joint propagation of ghosts and gluons. We
give a procedure to compute the contribution of each graph to a gluon Green
function, for arbitrarily polarized off-shell gluons, reducible and irreducible
diagrams, planar and non-planar topologies. Explicit examples are given for up
to six gluons.

</DOC>
<DOC>
<DOCNO> 85353 </DOCNO>
The status of the Lambda term in quantum geometrodynamics in extended


  S. Weinberg pointed out a way to introduce a cosmological term by modifying
the theory of gravity. This modification would be justified if the Einstein
equations with the cosmological term could be obtained in the classical limit
of some physically satisfied quantum theory of gravity. We propose to consider
quantum geometrodynamics in extended phase space as a candidate for such a
theory. Quantum geometrodynamics in extended phase space aims at giving a
selfconsistent description of the integrated system ``the physical object (the
Universe) + observation means'', observation means being represented by a
reference frame. The Lambda term appears in classical equations under certain
gauge conditions and characterizes the state of gravitational vacuum related to
a chosen reference frame. The eigenvalue spectrum of Lambda depends on a
concrete cosmological model and can be found by solving the Schrodinger
equation for a wave function of the Universe. The proposed version of quantum
geometrodynamics enables one to make predictions concerning probable values of
the Lambda term at various stages of cosmological evolution.

</DOC>
<DOC>
<DOCNO> 170386 </DOCNO>
Remarks on the semi-classical theory of three state system


  The semi-classical solution of the three state system is considered to study
the population inversion at and away from resonance. At resonance, it is shown
that if the system is initially populated either in the upper or in the lower
level, then the population oscillation occurs in a way which is quite different
from that if it is initially populated in the middle state. At off resonance,
there is gradual suppression of the population in the excited states and in the
asymptotic limit of the detuning, the system returns to its initial state.

</DOC>
<DOC>
<DOCNO> 8187 </DOCNO>
Numerical studies of domains and bubbles of Langmuir monolayers


  A numerical algorithm based on the finite element methods has been developed
to accurately determine the shape of the boundary of a domain containing
``boojum'' textures. Within the context of the simple model we adopt, the
effects of both bulk elastic anisotropy and line-tension anisotropy on the
domain boundary can be examined. It is found that line-tension anisotropy must
be present in order to account for domains with protruding features. Both
elastic anisotropy and anisotropic line-tension can result in domains with
indentations. The numerical algorithm has been extended to investigate the
problem of a bubble in extended region ordered phase.

</DOC>
<DOC>
<DOCNO> 121219 </DOCNO>
{Chemo-spectrophotometric evolution of spiral galaxies: IV. Star


  We study the star formation history of normal spirals by using a large and
homogeneous data sample of local galaxies. For our analysis we utilise detailed
models of chemical and spectrophotometric galactic evolution, calibrated on the
Milky Way disc. We find that star formation efficiency is independent of
galactic mass, while massive discs have, on average, lower gas fractions and
are redder than their low mass counterparts; put together, these findings
convincingly suggest that massive spirals are older than low mass ones. We
evaluate the effective ages of the galaxies of our sample and we find that
massive spirals must be several Gyr older than low mass ones. We also show that
these galaxies (having rotational velocities in the 80-400 km/s range) cannot
have suffered extensive mass losses, i.e. they cannot have lost during their
lifetime an amount of mass much larger than their current content of gas+stars.

</DOC>
<DOC>
<DOCNO> 99755 </DOCNO>
Distortion of leaves in product foliations


  We produce examples of codimension one foliations of the Euclidean and
hyperbolic planes with bounded geometry which are topologically products, but
for which leaves are non-recursively distorted. That is, the function which
compares intrinsic distances in leaves with extrinsic distances in the ambient
space grows faster than any recursive function.

</DOC>
<DOC>
<DOCNO> 68569 </DOCNO>
Lepton Pair Production at the LHC and the Gluon Density in the Proton


  The hadroproduction of lepton pairs with mass $Q$ and finite transverse
momentum $Q_T$ is dominated by quark-gluon scattering in the region $Q_T >
Q/2$. This feature provides a new independent method for constraining the gluon
density with data at hadron collider energies. Predictions are provided at the
energy of the LHC.

</DOC>
<DOC>
<DOCNO> 119026 </DOCNO>
Global Spiral Modes in NGC 1566: Observations and Theory


  We present an observational and theoretical study of the spiral structure in
galaxy NGC 1566. A digitized image of NGC 1566 in I-band was used for
measurements of the radial dependence of amplitude variations in the spiral
arms. We use the known velocity dispersion in the disk of NGC 1566, together
with its rotation curve, to construct linear and 2D nonlinear simulations which
are then compared with observations. A two-armed spiral is the most unstable
linear global mode in the disk of NGC 1566. The nonlinear simulations are in
agreement with the results of the linear modal analysis, and the theoretical
surface amplitude and the velocity residual variations across the spiral arms
are in qualitative agreement with the observations. The spiral arms found in
the linear and nonlinear simulations are considerably shorter than those
observed in the disk of NGC 1566. We argue therefore, that the surface density
distribution in the disk of the galaxy NGC 1566 was different in the past, when
spiral structure in NGC 1566 was linearly growing.

</DOC>
<DOC>
<DOCNO> 170027 </DOCNO>
Decoherence and the Final Pointer Basis


  Using a functional method it is demonstrated that a generic quantum system
evolves to a decohered state in a final pointer basis.

</DOC>
<DOC>
<DOCNO> 151039 </DOCNO>
Light-Cone Kaluza-Klein Geometry: Confined Propagation as a Particle


  A modified Kaluza-Klein theory is proposed in which propagation takes place
only at the speed of light. The propagation can be confined to a small volume,
forming a particle with rest mass. The usual four space-time coordinates locate
the confinement volume, and Kaluza's fifth coordinate is replaced by an
internal degree of freedom. Electromagnetism corresponds to a gauge field on
the phase of the internal motion. Self-gravity might create the confinement, as
in a geon, but the particle would have a Planck mass. This large mass could be
made closer to the masses of observed particles if gravity were allowed to
increase in strength within the confinement volume.

</DOC>
<DOC>
<DOCNO> 67980 </DOCNO>
A Two-Loop Four-Gluon Helicity Amplitude in QCD


  We present the two-loop pure gauge contribution to the gluon-gluon scattering
amplitude with maximal helicity violation. Our construction of the amplitude
does not rely directly on Feynman diagrams, but instead uses its analytic
properties in 4 - 2 epsilon dimensions. We evaluate the loop integrals
appearing in the amplitude through O(epsilon^0) in terms of polylogarithms.

</DOC>
<DOC>
<DOCNO> 178599 </DOCNO>
Isovector and isoscalar superfluid phases in rotating nuclei


  The subtle interplay between the two nuclear superfluids, isovector T=1 and
isoscalar T=0 phases, are investigated in an exactly soluble model. It is shown
that T=1 and T=0 pair-modes decouple in the exact calculations with the T=1
pair-energy being independent of the T=0 pair-strength and vice-versa. In the
rotating-field, the isoscalar correlations remain constant in contrast to the
well known quenching of isovector pairing. An increase of the isoscalar (J=1,
T=0) pair-field results in a delay of the bandcrossing frequency. This
behaviour is shown to be present only near the N=Z line and its experimental
confirmation would imply a strong signature for isoscalar pairing collectivity.
The solutions of the exact model are also discussed in the
Hartree-Fock-Bogoliubov approximation.

</DOC>
<DOC>
<DOCNO> 9575 </DOCNO>
Exclusion Statistics in Classical Mechanics


  We present a general method to derive the classical mechanics of a system of
identical particles in a way that retains information about quantum statistics.
The resulting statistical mechanics can be interpreted as a classical version
of Haldane's exclusion statistics.

</DOC>
<DOC>
<DOCNO> 72038 </DOCNO>
The b-quark EDM in SUSY and CP-odd bottomonium formation


  We compute the electric dipole moment (EDM) of the bottom quark in minimal
supersymmetric model (SUSY) with explicit CP violation. We estimate its upper
bound to be 10^(-20) e-cm where the dominant contribution comes from the
charginos for most of the SUSY parameter space. We also find that chargino
contribution is directly correlated with the branching fraction of the B\to X_s
\gamma decay. Furthermore, we analyze the formation of 1 P_1 resonance of the
(\bar{b}b) system in e^+ e^- annihilation, and show that the CP-violating
transition amplitude, induced solely by the b-quark EDM, is significantly
larger than the CP-conserving ones. Therefore, observation of this CP-odd
resonance in e^+ e^- annihilation will be a direct probe of the CP-violating
phases in SUSY. In case experiment cannot establish the existence of such a
CP-odd (\bar{b}b) state, then either sparticle masses of all three generations
will be pushed well above TeV, weakening the possibility of weak-scale SUSY, or
the sparticle mass spectrum will be tuned so as to cancel different
contributions to EDMs.

</DOC>
<DOC>
<DOCNO> 99786 </DOCNO>
Connections on locally trivial quantum principal fibre bundles


  Following the approach of Budzy\'nski and Kondracki, we define covariant
differential algebras and connections on locally trivial quantum principal
fibre bundles. We also consider covariant derivatives, connection forms and
curvatures and explore the relations between these notions. As an example, a
U(1) quantum principal bundle over a glued quantum sphere and a connection in
this bundle is constructed. This connection may be interpreted as a q-deformed
Dirac monopole.

</DOC>
<DOC>
<DOCNO> 122300 </DOCNO>
Status of the CANGAROO-III Project


  The CANGAROO-III project, a system of four 10 m telecopes dedicated for
gamma-ray astrophysics, has started in 1999 and is expected to complete in 2004
in Woomera, South Australia. We report the construction work during the first
year, which includes the completion of the first 10 m telescope built as a 7 m
telescope in 1999, and the work in progess to increase the performance by
constructing three more similar telescopes based on the experience gained
during the construction of the first telescope.

</DOC>
<DOC>
<DOCNO> 80721 </DOCNO>
On the colour confinement and the minimal surface


  In the analysis of the energy of the four-quark system obtained in the SU(2)
lattice Monte Carlo, the f-model in which the transition potential is expressed
in the form $f=f_c exp(-k_A b_s A-k_P\sqrt{b_s}P)$, where A is the area and P
is the perimeter of the Wilson loop, was successful in the simple
configurations of the four quarks. In the case of tetrahedral geometry, an
estimation of the minimal surface whose contours run the positions of the four
quarks is necessary. We show that the regular surface approximation whose area
can be calculated analytically, is a good approximation for evaluating the
minimal surface. The numerical value of the coefficient $k_A b_s$ is close to
$2 fm^{-2}$ which is the density of the $Z_2$ vortex in the SU(2) lattice Monte
Carlo.

</DOC>
<DOC>
<DOCNO> 117207 </DOCNO>
The decay of plane wave pulses with complex structure in a nonlinear


  Nonlinear plane acoustic waves propagating through a fluid are studied using
Burgers' equation with finite viscosity. The evolution of a simple N-pulse with
regular and random initial amplitude and of pulses with monochromatic and noise
carrier is considered. In the latter case the initial pulses are characterized
by two length scales. The length scale of the modulation function is much
greater than the period or the length scale of the carrier. With increasing
time the initial pulses are deformed and shocks appear. The finite viscosity
leads to a finite shock width, which does not depend on the fine structure of
the initial pulse and is fully determined by the shock position in the zero
viscosity limit. The other effect of nonzero viscosity is the shift of the
shock position from the position at zero viscosity. This shift, as well as the
linear time, at which the nonlinear stage of evolution changes to the linear
stage, depends on the fine structure of the initial pulse. It is also shown
that the nonlinearity of the medium leads to generation of a nonzero mean field
from an initial random field with zero mean value. The relative fluctuation of
the field is investigated both at the nonlinear and the linear stage.

</DOC>
<DOC>
<DOCNO> 11997 </DOCNO>
Adaptive learning by extremal dynamics and negative feedback


  We describe a mechanism for biological learning and adaptation based on two
simple principles: (I) Neuronal activity propagates only through the network's
strongest synaptic connections (extremal dynamics), and (II) The strengths of
active synapses are reduced if mistakes are made, otherwise no changes occur
(negative feedback). The balancing of those two tendencies typically shapes a
synaptic landscape with configurations which are barely stable, and therefore
highly flexible. This allows for swift adaptation to new situations.
Recollection of past successes is achieved by punishing synapses which have
once participated in activity associated with successful outputs much less than
neurons that have never been successful. Despite its simplicity, the model can
readily learn to solve complicated nonlinear tasks, even in the presence of
noise. In particular, the learning time for the benchmark parity problem scales
algebraically with the problem size N, with an exponent $k\sim 1.4$.

</DOC>
<DOC>
<DOCNO> 10184 </DOCNO>
On the reliability of mean-field methods in polymer statistical


  The reliability of the mean-field approach to polymer statistical mechanics
is investigated by comparing results from a recently developed lattice
mean-field theory (LMFT) method to statistically exact results from two
independent numerical Monte Carlo simulations for the problems of a polymer
chain moving in a spherical cavity and a polymer chain partitioning between two
confining spheres of different radii. It is shown that in some cases the
agreement between the LMFT and the simulation results is excellent, while in
others, such as the case of strongly fluctuating monomer repulsion fields, the
LMFT results agree with the simulations only qualitatively. Various
approximations of the LMFT method are systematically estimated, and the
quantitative discrepancy between the two sets of results is explained with the
diminished accuracy of the saddle-point approximation, implicit in the
mean-field method, in the case of strongly fluctuating fields.

</DOC>
<DOC>
<DOCNO> 69876 </DOCNO>
Black holes in the brane world:Time symmetric initial data


  We numerically construct time-symmetric initial data sets of a black hole in
the Randall-Sundrum brane world model, assuming that the black hole is
spherical on the brane. We find that the apparent horizon is cigar-shaped in
the 5D spacetime.

</DOC>
<DOC>
<DOCNO> 9235 </DOCNO>
Fate of the classical false vacuum


  Thermalisation of configurations with initial white noise power spectrum is
studied in numerical simulations of a classical one-component $\Phi^4$ theory
in 2+1 dimensions, coupled to a small amplitude homogenous external field. The
study is performed for energy densities corresponding to the broken symmetry
phase of the system in equilibrium. The effective equation of the order
parameter motion is reconstructed from its trajectory which starts from an
initial value near the metastable point and ends in the stable ground state.
This phenomenological theory quantitatively accounts for the decay of the false
vacuum. The large amplitude transition of the order parameter between the two
minima displays characteristics reflecting dynamical aspects of the Maxwell
construction.

</DOC>
<DOC>
<DOCNO> 118638 </DOCNO>
Spectroscopic identification of ten faint hard X-ray sources discovered


  We report optical spectroscopic identifications of 10 hard (2-10 keV) X-ray
selected sources discovered by Chandra. The X-ray flux of the sources ranges
between 1.5 and 25 x 10-14 cgs, the lower value being 3 times fainter than in
previous BeppoSAX and ASCA surveys. Their R band magnitudes are in the range
12.8-22. Six of the Chandra sources are broad line quasars with redshifts
between 0.42 and 1.19, while the optical identification of the remaining four
is quite varied: two are X-ray obscured, emission line AGN at z=0.272 and
z=0.683, one is a starburst galaxy at z=0.016 and one, most unusually, is an
apparently normal galaxy at z=0.158. These findings confirm and extend down to
fainter X-ray fluxes the BeppoSAX results, in providing samples with a wide
range of X-ray and optical properties. The ratio between the soft X-ray and the
optical luminosity of the z=0.158 galaxy is a factor at least 30 higher than
that of normal galaxies, and similar to those of AGN. The high X-ray luminosity
and the lack of optical emission lines suggest an AGN in which either continuum
beaming dominates, or emission lines are obscured or not efficiently produced.

</DOC>
<DOC>
<DOCNO> 83396 </DOCNO>
Toward the Rectilinear Crossing Number of $K_n$: New Drawings, Upper


  Scheinerman and Wilf (1994) assert that `an important open problem in the
study of graph embeddings is to determine the rectilinear crossing number of
the complete graph K_n.' A rectilinear drawing of K_n is an arrangement of n
vertices in the plane, every pair of which is connected by an edge that is a
line segment. We assume that no three vertices are collinear, and that no three
edges intersect in a point unless that point is an endpoint of all three. The
rectilinear crossing number of K_n is the fewest number of edge crossings
attainable over all rectilinear drawings of K_n.
  For each n we construct a rectilinear drawing of K_n that has the fewest
number of edge crossings and the best asymptotics known to date. Moreover, we
give some alternative infinite families of drawings of K_n with good
asymptotics. Finally, we mention some old and new open problems.

</DOC>
<DOC>
<DOCNO> 85478 </DOCNO>
Unboundable Spacetimes with Metric Singularities and Matching Metrics


  Singularity theorems of general relativity utilize the notion of causal
geodesic incompleteness as a criterion of the presence of a spacetime
singularity. The incompleteness of a causal curve implies the end and/or
beginning of the existence of a particle, which is an event. In the commonly
accepted approach, singularities are not incorporated into spacetime. Thus
spacetime turns out to be event-incomplete. With creation from nothing,
singularities are sources of lawlessness. A straightforward way around those
conceptual problems consists in including metric singularities in spacetime and
then matching metrics and causal geodesics at the singularities. To this end, a
spacetime manifold is assumed to be unboundable, so that singularities may only
be interior. The matching the geodesics is achieved through weakening
conditions for their smoothness. This approach is applied to a black-white hole
and a big crunch-bang.

</DOC>
<DOC>
<DOCNO> 9625 </DOCNO>
Strain versus stress in a model granular material: a Devil's staircase


  The series of equilibrium states reached by disordered packings of rigid,
frictionless discs in two dimensions, under gradually varying stress, are
studied by numerical simulations. Statistical properties of trajectories in
configuration space are found to be independent of specific assumptions ruling
granular dynamics, and determined by geometry only. A monotonic increase in
some macroscopic loading parameter causes a discrete sequence of
rearrangements. For a biaxial compression, we show that, due to the statistical
importance of such events of large magnitudes, the dependence of the resulting
strain on stress direction is a Levy flight in the thermodynamic limit.

</DOC>
<DOC>
<DOCNO> 121356 </DOCNO>
Deep near-infrared luminosity function of a cluster of galaxies at z=0.3


  The deep near-infrared luminosity function of AC118, a cluster of galaxies at
z=0.3, is presented. AC118 is a bimodal cluster, as evidenced both by our
near-infrared images of lensed galaxies, by public X-ray Rosat images and by
the spatial distribution of bright galaxies. Taking advantage of the extension
and depth of our data, which sample an almost unexplored region in the depth
vs. observed area diagram, we derive the luminosity function (LF), down to the
dwarf regime (M*+5), computed in several cluster portions. The overall LF,
computed on a 2.66 Mpc2 areas (H_0=50 km/s/Mpc), has an intermediate slope
(alpha=-1.2). However, the LF parameters depend on the surveyed cluster region:
the central concentration has 2.6^{+5.1}_{-1.7} times more bright galaxies and
5.3^{+7.2}_{-2.3} times less dwarfs per typical galaxy than the outer region,
which includes galaxies at an average projected distance of ~580 kpc (errors
are quoted at the 99.9 % confidence level). The LF in the secondary AC118 clump
is intermediate between the central and outer one. In other words, the
near-infrared AC118 LF steepens going from high to low density regions. At an
average clustercentric distance of ~580 kpc, the AC118 LF is statistically
indistinguishable from the LF of field galaxies at similar redshift, thus
suggesting that the hostile cluster environment plays a minor role in shaping
the LF at large clustercentric distances, while it strongly affects the LF at
higher galaxy density.

</DOC>
<DOC>
<DOCNO> 99777 </DOCNO>
Trees and Branches in Banach Spaces


  An infinite dimensional notion of asymptotic structure is considered. This
notion is developed in terms of trees and branches on Banach spaces. Every
countably infinite countably branching tree $\mathcal T$ of a certain type on a
space X is presumed to have a branch with some property. It is shown that then
X can be embedded into a space with an FDD $(E_i)$ so that all normalized
sequences in X which are almost a skipped blocking of $(E_i)$ have that
property. As an application of our work we prove that if X is a separable
reflexive Banach space and for some $1<p<\infty$ and $C<\infty$ every weakly
null tree $\mathcal T$ on the sphere of X has a branch C-equivalent to the unit
vector basis of $\ell_p$, then for all $\epsilon>0$, there exists a finite
codimensional subspace of X which $C^2+\epsilon$ embeds into the $\ell_p$ sum
of finite dimensional spaces.

</DOC>
<DOC>
<DOCNO> 118110 </DOCNO>
The relativistic iron line profile in the Seyfert 1 Galaxy IC4329a


  We present simultaneous ASCA and RXTE data on the bright Seyfert 1 galaxy
IC4329a. The iron line is significantly broadened, but not to the extent
expected from an accretion disk which extends down to the last stable orbit
around a black hole. We marginally detect a narrow line component, presumably
from the molecular torus, but even including this gives a line profile from the
accretion disk which is significantly narrower that that seen in MCG-6-30-15,
and is much more like that seen from the low/hard state galactic black hole
candidates. This is consistent with the inner disk being truncated before the
last stable orbit, forming a hot flow at small radii as in the ADAF models.
However, we cannot rule out the presence of an inner disk which does not
contribute to the reflected spectrum, either because of extreme ionisation
suppressing the characteristic atomic features of the reflected spectrum or
because the X-ray source is intrinsically anisotropic, so it does not
illuminate the inner disk.
  The source was monitored by RXTE every 2 days for 2 months, and these
snapshot spectra show that there is intrinsic spectral variability. The data
are good enough to disentangle the power law from the reflected continuum and
we see that the power law softens as the source brightens. The lack of a
corresponding increase in the observed reflected spectrum implies that either
the changes in disk inner radial extent/ionisation structure are small, or that
the variability is actually driven by changes in the seed photons which are
decoupled from the hard X-ray mechanism.

</DOC>
<DOC>
<DOCNO> 101189 </DOCNO>
G-actions on graphs


  Let G be an n-dimensional torus and $\tau$ a Hamiltonian action of G on a
compact symplectic manifold, M. If M is pre-quantizable one can associate with
$\tau$ a representation of G on a virtual vector space, Q(M), by
$\spin^{\CC}$-quantization. If M is a symplectic GKM manifold we will show that
several well-known theorems about this ``quantum action'' of G: for example,
the convexity theorem, the Kostant multiplicity theorem and the ``quantization
commutes with reduction'' theorem for circle subgroups of G, are basically just
theorems about G-actions on graphs.

</DOC>
<DOC>
<DOCNO> 84485 </DOCNO>
Living on the edge: cosmology on the boundary of anti-de Sitter space


  We sketch a particularly simple and compelling version of D-brane cosmology.
Inspired by the semi-phenomenological Randall--Sundrum models, and their
cosmological generalizations, we develop a variant that contains a single
(3+1)-dimensional D-brane which is located on the boundary of a single bulk
(4+1)-dimensional region. The D-brane boundary is itself to be interpreted as
our visible universe, with ordinary matter (planets, stars, galaxies) being
trapped on this D-brane by string theory effects. The (4+1)-dimensional bulk
is, in its simplest implementation, adS_{4+1}, anti-de Sitter space. We
demonstrate that a k=+1 closed FLRW universe is the most natural option, though
the scale factor could quite easily be so large as to make it operationally
indistinguishable from a k=0 spatially flat universe. (With minor loss of
elegance, spatially flat and hyperbolic FLRW cosmologies can also be
accommodated.) We demonstrate how this model can be made consistent with
standard cosmology, and suggest some possible observational tests.

</DOC>
<DOC>
<DOCNO> 70357 </DOCNO>
Kaon properties and cross sections in nuclear medium


  Results for the $\pi + N \to \Lambda, \Sigma + K$ reactions in nuclear matter
of Ref. nucl-th/0004011 are presented. To evaluate the in-medium modification
of the reaction amplitude as a function of the baryonic density we introduce
relativistic, mean-field potentials for the initial, final and intermediate
mesonic and baryonic states in the resonance model. These vector and scalar
potentials were calculated using the quark meson coupling model. Contrary to
earlier work which has not allowed for the change of the cross section in
medium, we find that the data for kaon production at SIS energies are
consistent with a repulsive $K^+$-nucleus potential.

</DOC>
<DOC>
<DOCNO> 70242 </DOCNO>
The WIMP annual modulation signal and non-standard halo models


  Currently the best prospect for detecting Weakly Interacting Massive
Particles (WIMPs) is via the annual modulation, which occurs due to the Earth's
rotation around the Sun, of the direct detection signal. We investigate the
effect of uncertainties in our knowledge of the structure of the galactic halo
on the WIMP annual modulation signal. We compare the signal for three
non-standard halo models: Evans' power-law halos, Michie models with an
asymmetric velocity distribution and Maxwellian halos with bulk rotation. We
then compare the theoretical predictions of these models with the experimental
signal found by the DAMA experiment and investigate how the WIMP mass and
interaction cross section determined depend on the halo model assumed. We find
that the WIMP mass confidence limits are significantly extended to larger
masses, with the shape of the allowed region in the mass-cross section plane
depending on the model.

</DOC>
<DOC>
<DOCNO> 122522 </DOCNO>
Explosive Nucleosynthesis in Aspherical Hypernova Explosions and Late


  Aspherical explosion models for the hypernova (hyper-energetic supernova) SN
1998bw are presented. Nucleosynthesis in aspherical explosions is examined with
a two-dimensional hydrodynamical code and a detailed nuclear reaction network.
Aspherical explosions lead to a strong $\alpha$-rich freezeout, thus enhancing
the abundance ratios [$^{44}$Ca, $^{48}$Ti, and $^{64}$Zn / Fe] in the ejecta.
The nebular line profiles of the Fe-dominated blend near 5200 \AA and of [\OI]
6300,6363 \AA are calculated and compared with the observed late time spectra
of SN 1998bw. Compared with the spherical model, the unusual features of the
observed nebular spectra can be better explained if SN 1998bw is a strongly
aspherical explosion with a kinetic energy of $\sim 10^{52}$ ergs viewed from
near the jet direction.

</DOC>
<DOC>
<DOCNO> 102416 </DOCNO>
On rational curves in n-space with given normal bundle


  The stable rationality of components of the moduli space of (unparametrized)
rational curves in projective $n$-space with fixed normal bundle is proved,
provided these components dominate the moduli space of immersed rational curves
in the plane.

</DOC>
<DOC>
<DOCNO> 101435 </DOCNO>
On chiral differential operators over homogeneous spaces


  In this note we study algebras of chiral differential operators over an
algebraic group and over homogeneous spaces $G/G'$ where $G$ is simple and $G'$
is unipotent or parabolic.

</DOC>
<DOC>
<DOCNO> 100787 </DOCNO>
Numerical analysis of the Novikov problem of a normal metal in a strong


  We present the results of our numerical exploration of the fractal structure
found by S.P. Novikov in the problem of the behviour of magnetoresistance in a
normal metal under a strong magnetic field. The case we discuss in this paper
is the simplest non-trivial one, namely the case of 2 Fermi Surfaces that cut
the brillouin zone along of the coordinate axes (i.e. Fermi surfaces have genus
3).

</DOC>
<DOC>
<DOCNO> 99487 </DOCNO>
The elliptic curve in the S-duality theory and Eisenstein series for


  We establish a relation between the generating functions appearing in the
S-duality conjecture of Vafa and Witten and geometric Eisenstein series for
Kac-Moody groups. For a pair consisting of a surface and a curve on it, we
consider a refined geometric function E (involving G-bundles with parabolic
structures along the curve) which depends both on elliptic and modular
variables. We prove a functional equation for E with respect to the affine Weyl
group, thus establishing the elliptic behavior. When the curve is P^1, we
calculate the Eisenstein-Kac-Moody series explicitly and it turns out to be a
certain deformation of an irreducible Kac-Moody character, more precisely, an
analog of the Hall-Littlewood polynomial for the affine root system. We also
get an explicit formula for the universal blowup function for any simply
connected structure group.

</DOC>
<DOC>
<DOCNO> 69862 </DOCNO>
Probe of CP Violation in e+e- -> ttbar Near Threshold


  We report our theoretical study on how to probe the anomalous CP-violating
couplings of the top quark in the ttbar region at future e+e- linear colliders.
We focus on the unique role of the ttbar threshold region.

</DOC>
<DOC>
<DOCNO> 12751 </DOCNO>
Stability Puzzles in Phage Lambda


  The lysogeny maintenance switch in phage lambda is one of the simplest
examples on the molecular level of computation, command and control in a living
system. If, following infection of the bacterium E. coli, the virus enters the
lysogenic pathway, it represses its developmental functions, and integrates its
DNA into the host chromosome. In this state the prophage may be passively
replicated for many generations of E. coli. In fact, this repressed state is
intrinsically more stable than the gene encoding the repressor. We develop a
mathematical formalism to predict the stability of such epigenetic states from
affinities of the molecular components. We apply the model to the behavior of
recently published mutants at the right operator complex of lambda, and find
that the reported stability indicates that the current view of the switch is
incomplete. The approach described here should be generally applicable to the
stability of expressed states

</DOC>
<DOC>
<DOCNO> 178986 </DOCNO>
Nuclear Pairing in the T=0 channel revisited


  Recent published data on the isoscalar gap in symmetric nuclear matter using
the Paris force and the corresponding BHF single particle dispersion are
corrected leading to an extremely high proton-neutron gap of $\Delta \sim 8$
MeV at $\rho \sim 0.5\rho_0$. Arguments whether this value can be reduced due
to screening effects are discussed. A density dependent delta interaction with
cut off is adjusted so as to approximately reproduce the nuclear matter values
with the Paris force.

</DOC>
<DOC>
<DOCNO> 118419 </DOCNO>
A limit for the mass transfer rate in soft X-ray transients


  Many black hole X-ray transients are in a low state for several decades until
an outburst occurs. We interpret this outburst behaviour as a marginal
occurrence of a dwarf nova type disk instability in the cool outer accretion
disk. We compute the disk evolution including evaporation of matter from the
cool thin disk. This evaporation process causes the transition to a hot coronal
flow. The efficiency depends on the black hole mass.
  The new results are the dependence of the outburst recurrence time on the
mass transfer rate from the companion star and the fraction of the matter which
is accumulated in the disk for the outburst. We determine a lower limit of the
mass transfer rate, below which no disk instability can be triggered. We find
that for rates slightly lower than those in the known black hole X-ray
transients the disk would be stationary. We argue that many such optically
faint black hole X-ray binaries with stationary cool accretion disks exist.

</DOC>
<DOC>
<DOCNO> 118050 </DOCNO>
A New Complete Sample of Sub-millijansky Radio Sources: An Optical and


  The Very Large Array (VLA) has been used in C-configuration to map an area
\~0.3 square degrees at 1.4 GHz with 5sigma sensitivities of 0.305, 0.325,
0.380 and 0.450 mJy/beam over four equal subareas. Radio properties are
presented for 62 detected sources. Deep optical imaging to Gunn r~25 mag using
the Hale 5-m telescope covering ~0.21 square degrees is reported for a subset
of 43 sources. This optical follow-up is much deeper than that of existing
larger area radio surveys of similar radio sensitivity. Archival J, H and
K-band photometry from the Two-Micron All Sky Survey (2MASS) is also presented.
Using a robust likelihood-ratio technique, we optically identified 26 radio
sources with probabilities >80%. Nine are uncertain/ambiguous detections and
eight are empty fields. Comparisons with a stellar synthesis model that
includes radio emission and dust reddening suggests that the
near-infrared--to--optical emission in a small, bright sub-sample is reddened
by `optically-thin' dust with absorption A_V ~ 2-2.5 mag, regardless of
morphological type. This is consistent with other, more direct determinations
of absorption. The radio--to--optical(--near-infrared) flux ratios of
early-type galaxies require significant contamination in the radio by an active
galactic nucleus (AGN), consistent with the current paradigm. Using our simple
modeling approach, we also discuss a potential diagnostic for selecting
Ultraluminous Infrared Galaxies (ULIGS) to z~1.6 from microJansky radio
surveys.

</DOC>
<DOC>
<DOCNO> 13104 </DOCNO>
Noise Effects on the Complex Patterns of Abnormal Heartbeats


  Patients at high risk for sudden death often exhibit complex heart rhythms in
which abnormal heartbeats are interspersed with normal heartbeats. We analyze
such a complex rhythm in a single patient over a 12-hour period and show that
the rhythm can be described by a theoretical model consisting of two
interacting oscillators with stochastic elements. By varying the magnitude of
the noise, we show that for an intermediate level of noise, the model gives
best agreement with key statistical features of the dynamics.

</DOC>
<DOC>
<DOCNO> 69032 </DOCNO>
Ultrahigh energy neutrino interactions and weak-scale string theories


  It has been suggested that ultrahigh energy neutrinos can acquire
cross-sections approaching hadronic size if the string scale is as low as 1-10
TeV. In this case, the vertical air showers observed with energies above the
Greisen-Zatsepin-Kuzmin cutoff at E approximately 6x10^{19} eV could be
initiated by neutrinos which are the only known primaries able to travel long
distances unimpeded. We have calculated the neutrino-nucleon cross-section due
to the exchange of Kaluza-Klein excitations of the graviton in a field
theoretical framework. We have found that the neutrino-nucleon cross section
and the transferred energy per interaction are too small to explain vertical
showers even in the most optimistic scenario.

</DOC>
<DOC>
<DOCNO> 99855 </DOCNO>
Geodesic connectedness and conjugate points in GRW spacetimes


  Given two points of a Generalized Robertson-Walker spacetime, the existence,
multiplicity and causal character of geodesic connecting them is characterized.
Conjugate points of such geodesics are related to conjugate points of geodesics
on the fiber, and Morse-type relations are obtained. Applications to
bidimensional spacetimes and to GRW spacetimes satisfying the timelike
convergence condition are also found.

</DOC>
<DOC>
<DOCNO> 72146 </DOCNO>
b Quark Physics with 2 .10^9 Z Bosons


  It has been suggested to realize a factory for 10^9 Z^0 through a linear
e^+e^- collider with polarized beams. Very likely the relevant CP studies for B
mesons will already have been performed at the B factories by that time, hence
GIGA-Z will be a third generation b physics experiment. Yet such a facility
would provide us with unique opportunities in the domain of beauty physics that
would be of essential significance even in 2010: (1) Production and decay of
polarized beauty baryons; (2) searching for and probing transitions driven by b
--> q \nu \bar{\nu}; (3) detailed and comprehensive studies of inclusive
semileptonic B_s decays.

</DOC>
<DOC>
<DOCNO> 69173 </DOCNO>
NLO QCD Corrections to the Polarized Photo- and Hadroproduction of Heavy


  The complete details of our calculation of the NLO QCD corrections to heavy
flavor photo- and hadroproduction with longitudinally polarized initial states
are presented. The main motivation for investigating these processes is the
determination of the polarized gluon density at the COMPASS and RHIC
experiments, respectively, in the near future. All methods used in the
computation are extensively documented, providing a self-contained introduction
to this type of calculations. Some employed tools also may be of general
interest, e.g., the series expansion of hypergeometric functions. The relevant
parton level results are collected and plotted in the form of scaling
functions. However, the simplification of the obtained gluon-gluon virtual
contributions has not been completed yet. Thus NLO phenomenological predictions
are only given in the case of photoproduction. The theoretical uncertainties of
these predictions, in particular with respect to the heavy quark mass, are
carefully considered. Also it is shown that transverse momentum cuts can
considerably enhance the measured production asymmetries. Finally unpolarized
heavy quark production is reviewed in order to derive conditions for a
successful interpretation of future spin-dependent experimental data.

</DOC>
<DOC>
<DOCNO> 116550 </DOCNO>
Enhanced four-wave mixing via elimination of inhomogeneous broadening by


  We show that atoms from wide velocity interval can be concurrently involved
in Doppler-free two-photon resonant far from frequency degenerate four-wave
mixing with the aid of auxiliary electromagnetic field. This gives rise to
substantial enhancement of the output radiation generated in optically thick
medium. Numerical illustrations addressed to typical experimental conditions
are given.

</DOC>
<DOC>
<DOCNO> 10680 </DOCNO>
Bose-Einstein condensation of two interacting particles


  We investigate the notion of Bose-Einstein condensation of interacting
particles. The definition of the condensate is based on the existence of the
dominant eigenvalue of the single-particle density matrix. The statistical
properties and the characteristic temperature are computed exactly in the
soluble models of two interacting atoms.

</DOC>
<DOC>
<DOCNO> 150709 </DOCNO>
Conformal primaries of OSp(8/4,R) and BPS states in AdS4


  We derive short UIR's of the OSp(8/4,R) superalgebra of 3d N=8 superconformal
field theories by the requirement that the highest weight states are
annihilated by a subset of the super-Poincare odd generators. We then find a
superfield realization of these BPS saturated UIR's as "composite operators" of
the two basic ultrashort "supersingleton" multiplets. These representations are
the AdS4 analogue of BPS states preserving different fractions of supersymmetry
and are therefore suitable to classify perturbative and non-perturbative
excitations of M-theory compactifications.

</DOC>
<DOC>
<DOCNO> 70806 </DOCNO>
Effects of anomalous couplings of the tau lepton


  The dimension-six CP-conserving $SU_L(2)\times U_Y(1)$ invariant operators
involving the tau lepton are studied. It leads to the new physics effects to
the lepton flavor violation (LFV) and lepton flavor-changing neutral
current(FCNC). With the available experimental data on the decays $Z \to \tau^+
+ \tau^- $, $Z\to \mu^+ + \mu^- $ and $\mu^- \to e^- +\gamma$, the constraints
on parameters of the effective lagrangian can be given. According to such
constraints, the branching ratio of the decay $Z\to \mu^\pm + \tau^\mp $ could
reach to $10^{-6}-10^{-7}$. The size of the LFV effects depends crucially on
the dynamics of the lepton mass generation. Assuming the lepton mass matrices
in the form of a Fritzsch ansatz, we point out that the experiment on $\mu\to e
\gamma$ will put stronger limits on the anomalous magnitic and electric dipole
moments of the tau lepton than obtained by Escribano and Mass\'{o}.

</DOC>
<DOC>
<DOCNO> 120129 </DOCNO>
Dark Matter and Cold Fractal Clouds


  There is strong evidence for a large fraction of dark matter in the Universe.
Some of the evidence and candidates for dark matter are reviewed. Dark matter
in spiral galaxies may be in the form of cold dense clouds of molecular
hydrogen. This model is presented in more detail and perspectives for detecting
the cold H_2 are discussed.

</DOC>
<DOC>
<DOCNO> 70166 </DOCNO>
Hyperon Enhancement in the Dual Parton Model


  We review the two sources of hyperon enhancement in the dual parton model:
strings originating from diquark-antidiquark pairs in the nucleon sea and net
baryons containing two or three sea quarks with a yield controlled by the
observed stopping. We show that adding final state interactions (including
strangeness exchange reactions as well as the inverse reactions required by
detailed balance) with a single averaged cross-section $\sigma=0.2$ mb, we can
explain the observed hyperon enhancement in PbPb collisions at CERN SPS.

</DOC>
<DOC>
<DOCNO> 99575 </DOCNO>
Cubic Surfaces and Borcherds Products


  The moduli space of cubic surfaces in complex projective space is known to be
isomorphic to the quotient of the complex 4-ball by a certain arithmetic group.
We apply Borcherds' techniques to construct automorphic forms for this group
and show that these provide an embedding of the moduli space in 9-dimensional
projective space. We also show that our automorphic forms directly encode the
geometry of cubic surfaces, by showing that each of Cayley's invariants
(certain cross-ratios) is simply a quotient of two of our automorphic forms.

</DOC>
<DOC>
<DOCNO> 170502 </DOCNO>
Artificial Orbitals and a Solution to Grover's Problem


  By allowing measurements of observables other than the state of the qubits in
a quantum computer, one can find eigenvectors very quickly. If a unitary
operation U is implemented as a time-independent Hamiltonian, for instance, one
can collapse the state of the computer to a nearby eigenvector of U with a
measurement of the energy. We examine some recent proposals for quantum
computation using time-independent Hamiltonians and show how to convert them
into ``artificial orbitals'' whose energy eigenstates match those of U. This
system can be used to find eigenvectors and eigenvalues with a single
measurement. We apply this technique to Grover's algorithm and the continuous
variant proposed by Farhi and Gutmann.

</DOC>
<DOC>
<DOCNO> 11059 </DOCNO>
Hydrogen-Bonded Liquids: Effects of Correlations of Orientational


  We improve a lattice model of water introduced by Sastry, Debenedetti,
Sciortino, and Stanley to give insight on experimental thermodynamic anomalies
in supercooled phase, taking into account the correlations between
intra-molecular orientational degrees of freedom. The original Sastry et al.
model including energetic, entropic and volumic effect of the
orientation-dependent hydrogen bonds (HBs), captures qualitatively the
experimental water behavior, but it ignores the geometrical correlation between
HBs. Our mean-field calculation shows that adding these correlations gives a
more water-like phase diagram than previously shown, with the appearance of a
solid phase and first-order liquid-solid and gas-solid phase transitions.
Further investigation is necessary to be able to use this model to characterize
the thermodynamic properties of the supercooled region.

</DOC>
<DOC>
<DOCNO> 13435 </DOCNO>
Simulation of Material Properties Below the Debye Temperature: A


  Classical and path integral molecular dynamics (PIMD) simulations are used to
study alpha-quartz and beta-quartz in a large range of temperatures at zero
external stress. PIMD account for quantum fluctuations of atomic vibrations,
which can modify material properties at temperatures below the Debye
temperature. The difference between classical and quantum mechanical results
for bond lengths, bond angles, elastic modulii, and some dynamical properties
is calculated and comparison to experimental data is done. Only quantum
mechanical simulations are able to reflect the correct thermomechanical
properties below room temperature. It is discussed in how far classical and
PIMD simulations can be helpful in constructing improved potential energy
surfaces for silica.

</DOC>
<DOC>
<DOCNO> 11198 </DOCNO>
Statistics of velocity gradients in two-dimensional Navier-Stokes and


  Probability density functions and conditional averages of velocity gradients
derived from upper ocean observations are compared with results from forced
simulations of the two-dimensional Navier-Stokes equations. Ocean data are
derived from TOPEX satellite altimeter measurements. The simulations use rapid
forcing on large scales, characteristic of surface winds. The probability
distributions of transverse velocity derivatives from the ocean observations
agree with the forced simulations, though they differ from unforced simulations
reported elsewhere. The distribution and cross-correlation of velocity
derivatives provide clear evidence that large coherent eddies play only a minor
role in generating the observed statistics.

</DOC>
<DOC>
<DOCNO> 119903 </DOCNO>
Loose Groups of Galaxies in the Las Campanas Redshift Survey


  A ``friends-of-friends'' percolation algorithm has been used to extract a
catalogue of dn/n = 80 density enhancements (groups) from the six slices of the
Las Campanas Redshift Survey (LCRS). The full catalogue contains 1495 groups
and includes 35% of the LCRS galaxy sample. A clean sample of 394 groups has
been derived by culling groups from the full sample which either are too close
to a slice edge, have a crossing time greater than a Hubble time, have a
corrected velocity dispersion of zero, or contain a 55-arcsec ``orphan'' (a
galaxy with a mock redshift which was excluded from the original LCRS redshift
catalogue due to its proximity to another galaxy -- i.e., within 55 arcsec).
Median properties derived from the clean sample include: line-of-sight velocity
dispersion sigma_los = 164km/s, crossing time t_cr = 0.10/H_0, harmonic radius
R_h = 0.58/h Mpc, pairwise separation R_p = 0.64/h Mpc, virial mass M_vir =
(1.90x10^13)/h M_sun, total group R-band luminosity L_tot = (1.30x10^11)/h^2
L_sun, and R-band mass-to-light ratio M/L = 171h M_sun/L_sun; the median number
of observed members in a group is 3.

</DOC>
<DOC>
<DOCNO> 118822 </DOCNO>
A Theoretical Light-Curve Model for the Recurrent Nova V394 Coronae


  A theoretical light curve for the 1987 outburst of V394 Coronae Austrinae
(V394 CrA) is modeled to obtain various physical parameters of this recurrent
nova. We then apply the same set of parametersto a quiescent phase and confirm
that these parameters give a unified picture of the binary. The early visual
light curve (1-10 days after the optical maximum) is well reproduced by a
thermonuclear runaway model on a very massive WD close to the Chandrasekhar
limit (1.37 +- 0.01 M_sun). The ensuing plateau phase (10-30 days) is also
reproduced by the combination of a slightly irradiated MS and a fully
irradiated flaring-up disk with a radius ~1.4 times the Roche lobe size. The
best fit parameters are the WD mass 1.37 M_sun, the companion mass 1.5 M_sun
(0.8-2.0 M_sun is acceptable), the inclination angle of the orbit i~65-68
degree, and the flaring-up rim ~0.30 times the disk radius. The envelope mass
at the optical peak is estimated to be ~6 x 10^{-6} M_sun, which indicates an
average mass accretion rate of 1.5 x 10^{-7} M_sun yr^{-1} during the quiescent
phase between the 1949 and 1987 outbursts. In the quiescent phase, the observed
light curve can be reproduced with a disk size of 0.7 times the Roche lobe size
and a rather slim thickness of 0.05 times the accretion disk size at the rim.
About 0.5 mag sinusoidal variation of the light curve requires the mass
accretion rate higher than ~1.0 x 10^{-7} M_sun yr^{-1}, which is consistent
with the above estimation from the 1987 outburst. These newly obtained
quantities are exactly the same as those predicted in a new progenitor model of
Type Ia supernovae.

</DOC>
<DOC>
<DOCNO> 101039 </DOCNO>
Holonomy and parallel transport for Abelian gerbes


  In this paper we establish a one-to-one correspondence between $S^1$-gerbes
with connections, on the one hand, and their holonomies, for simply connected
manifolds, or their parallel transports, in the general case, on the other
hand. This result is a higher-order analogue of the familiar equivalence
between bundles with connections and their holonomies for connected manifolds.
The holonomy of a gerbe with group $S^1$ on a simply connected manifold $M$ is
a group morphism from the thin second homotopy group to $S^1$, satisfying a
smoothness condition, where a homotopy between maps from $[0,1]^2$ to $M$ is
thin when its derivative is of rank $\leq 2$. For the non-simply connected
case, holonomy is replaced by a parallel transport functor between two monoidal
Lie groupoids. The reconstruction of the gerbe and connection from its holonomy
is carried out in detail for the simply connected case. Our approach to abelian
gerbes with connections holds out prospects for generalizing to the non-abelian
case via the theory of double Lie groupoids.

</DOC>
<DOC>
<DOCNO> 150640 </DOCNO>
Geometric Construction of AdS Twistors


  Time-like geodesics in AdS_4, AdS_5 and AdS_7 are constructed geometrically
and independently of choice of AdS coordinates from division algebra spinors of
the corresponding AdS groups, explaining and generalising the construction by
Claus et al. of AdS_5 twistors.

</DOC>
<DOC>
<DOCNO> 68740 </DOCNO>
Exact non-factorizable O(alpha_s g^2) two-loop contribution to Z -> b


  For Z -> b bbar, we calculate all the two-loop top dependent Feynman graphs,
which have mixed QCD and electroweak contributions that are not factorizable.
For evaluating the graphs, without resorting to a mass expansion, we apply a
two-loop extension of the one-loop Passarino-Veltman reduction. This is an
analytic-numerical method, which first converts all diagrams into a set of ten
standard scalar functions, and then integrates them numerically over the
remaining Feynman parameters, with rapid convergence and high accuracy. We
discuss the treatment of infrared singularities within our methods. We do not
resort to unitarity cuts of two-point functionsfor calculating decay rates;
these are useful only to obtain an inclusive rate. For this reason,
experimental cuts and the experimental infrared energy resolution can be
implemented in our calculation, once the corresponding one-loop gluon
Bremsstrahlung process is added to this calculation.

</DOC>
<DOC>
<DOCNO> 70310 </DOCNO>
Non-factorizable effects in the $B-\bar B$ mixing


  We analyse the corrections to factorization for the $B-\bar B$ mixing
amplitude assuming that non-factorizable soft gluon exchanges can be described
by the local gluon condensate. Within this approximation the $<\alpha_s
GG>$-correction to the mixing amplitude can be expressed through the $B$-meson
transition form factors at zero momentum transfer. The correction is negative
independent of the particular values of the form factors.
  As a next step, we study these form factors making use of the relativistic
dispersion approach based on the constituent quark picture. We obtain spectral
representations for the form factors in terms of the $B$-meson soft wave
function and the propagator of the color-octet $b\bar q$ system. The $B$-meson
wave function has been determined previously from weak exclusive B decays, so
the main uncertainty in our estimates comes from the unknown details of the
propagator in the nonperturbative region. We obtain $\Delta
B_{B_d}(m_b)=-0.06\pm 0.035 $ and $\Delta B_{B_s}(m_b)=-0.05\pm 0.03 $.

</DOC>
<DOC>
<DOCNO> 116388 </DOCNO>
Energy distribution analysis of the wavepacket simulations of CH4 and


  The isotope effect in the scattering of methane is studied by wavepacket
simulations of oriented CH4 and CD4 molecules from a flat surface including all
nine internal vibrations. At a translational energy up to 96 kJ/mol we find
that the scattering is still predominantly elastic, but less so for CD4. Energy
distribution analysis of the kinetic energy per mode and the potential energy
surface terms, when the molecule hits the surface, are used in combination with
vibrational excitations and the corresponding deformation. They indicate that
the orientation with three bonds pointing towards the surface is mostly
responsible for the isotope effect in the methane dissociation.

</DOC>
<DOC>
<DOCNO> 70745 </DOCNO>
Spectator effects and quark-hadron duality in inclusive beauty decays


  The two important issues concerning the theory of inclusive decays are
studied: (1) evaluation of expectation values of four-quark operators in order
to systematically include the spectator effects and (2) estimation of duality
breaking corrections in heavy quark expansion. Our study leads to the
theoretical prediction of the ratio of lifetimes of $\Lambda_b$ and $B$ close
to the experimental one and the duality breaking corrections of about 10% of
the leading decay rate.

</DOC>
<DOC>
<DOCNO> 12897 </DOCNO>
Hierarchical learning in polynomial Support Vector Machines


  We study the typical properties of polynomial Support Vector Machines within
a Statistical Mechanics approach that allows us to analyze the effect of
different normalizations of the features. If the normalization is adecuately
chosen, there is a hierarchical learning of features of increasing order as a
function of the training set size.

</DOC>
<DOC>
<DOCNO> 70513 </DOCNO>
Strange mesons from quark and hadron matter: a comparison


  In a simplified model we study the hadronization of quark matter in an
expanding fireball, in particular the approach to a final hadronic composition
in equilibrium. Ideal hadron gas equilibrium constrained by conservation laws,
the fugacity parametrization, as well as linear and non-linear coalescence
approaches are recognized as different approximations to this in-medium quark
fusion process. It is shown that color confinement requires a dependence of the
hadronization cross section on quark density in the presence of flow (dynamical
confinement).

</DOC>
<DOC>
<DOCNO> 169631 </DOCNO>
Husimi Transform of an Operator Product


  It is shown that the series derived by Mizrahi, giving the Husimi transform
(or covariant symbol) of an operator product, is absolutely convergent for a
large class of operators. In particular, the generalized Liouville equation,
describing the time evolution of the Husimi function, is absolutely convergent
for a large class of Hamiltonians. By contrast, the series derived by
Groenewold, giving the Weyl transform of an operator product, is often only
asymptotic, or even undefined. The result is used to derive an alternative way
of expressing expectation values in terms of the Husimi function. The advantage
of this formula is that it applies in many of the cases where the anti-Husimi
transform (or contravariant symbol) is so highly singular that it fails to
exist as a tempered distribution.

</DOC>
<DOC>
<DOCNO> 101817 </DOCNO>
Properties of perturbative solutions of unilateral matrix equations


  A left-unilateral matrix equation is an algebraic equation of the form $$
a_0+a_1 x+a_2 x^2+... +a_n x^n=0 $$ where the coefficients $a_r$ and the
unknown $x$ are square matrices of the same order and all coefficients are on
the left (similarly for a right-unilateral equation). Recently certain
perturbative solutions of unilateral equations and their properties have been
discussed. We present a unified approach based on the generalized Bezout
theorem for matrix polynomials. Two equations discussed in the literature,
their perturbative solutions and the relation between them are described. More
abstractly, the coefficients and the unknown can be taken as elements of an
associative, but possibly noncommutative, algebra.

</DOC>
<DOC>
<DOCNO> 117177 </DOCNO>
Large-Scale Simulation of Beam Dynamics in High Intensity Ion Linacs


  In this paper we present results of using parallel supercomputers to simulate
beam dynamics in next-generation high intensity ion linacs. Our approach uses a
three-dimensional space charge calculation with six types of boundary
conditions. The simulations use a hybrid approach involving transfer maps to
treat externally applied fields (including rf cavities) and parallel
particle-in-cell techniques to treat the space-charge fields. The large-scale
simulation results presented here represent a three order of magnitude
improvement in simulation capability, in terms of problem size and speed of
execution, compared with typical two-dimensional serial simulations. Specific
examples will be presented, including simulation of the spallation neutron
source (SNS) linac and the Low Energy Demonstrator Accelerator (LEDA) beam halo
experiment.

</DOC>
<DOC>
<DOCNO> 102780 </DOCNO>
Invitation to higher local fields, Part I, section 15: On the structure


  This work contains a list of all known results on the quotient filtration on
the Milnor K-groups of a complete discrete valuation field in terms of
differential modules over the residue field . Author's recent study of the case
of a tamely ramified field of characteristic 0 with residue field of
characteristic p by using an exponential map and a syntomic complex is
explained.

</DOC>
<DOC>
<DOCNO> 120119 </DOCNO>
Spectroscopic confirmation of a cluster of galaxies at z=1 in the field


  We present new optical data on the cluster AX J2019+1127 identified by the
X-ray satellite ASCA at z\sim 1 (Hattori et al. 1997). The data suggest the
presence of a high-redshift cluster of galaxies responsible for the large
separation triple quasar MG2016+112. Our deep photometry reveals an excess of
z\sim 1 galaxy candidates, as already suspected by Benitez et al. (1999). Our
spectroscopic survey of 44 objects in the field shows an excess of 6 red
galaxies securely identified at z \sim 1, with a mean redshift of z =1.005 +/-
0.002. We estimate a velocity dispersion of \sigma = 771 (+430/-160) km s(-1)
based on these 6 galaxies and a V-band mass-to-light ratio of 215 (+308/-77)
h_50 M/L_sol. Our observations thus confirm the existence of a massive
structure acting as the lens, which explains the unusual configuration of the
triple quasar. Hence, there is no more need to invoke the existence of a ``dark
cluster'' to understand this lens system.

</DOC>
<DOC>
<DOCNO> 118879 </DOCNO>
GRBs from unstable Poynting dominated outflows


  Poynting flux driven outflows from magnetized rotators are a plausible
explanation for gamma-ray burst engines. We suggest a new possibility for how
such outflows might transfer energy into radiating particles. We argue that the
Poynting flux drives non-linearly unstable large amplitude electromagnetic
waves (LAEMW) which ``break'' at radii $r_t \sim 10^{14} $ cm where the MHD
approximation becomes inapplicable. In the ``foaming'' (relativisticly
reconnecting) regions formed during the wave breaks the random electric fields
stochastically accelerate particles to ultrarelativistic energies which then
radiate in turbulent electromagnetic fields. The typical energy of the emitted
photons is a fraction of the fundamental Compton energy $ \epsilon \sim f \hbar
c/r_e $ with $f \sim 10^{-3}$ plus additional boosting due to the bulk motion
of the medium. The emission properties are similar to synchrotron radiation,
with a typical cooling time $\sim 10^{-4}$ sec. During the wave break, the
plasma is also bulk accelerated in the outward radial direction and at larger
radii can produce afterglows due to the interactions with external medium. The
near equipartition fields required by afterglow models maybe due to magnetic
field regeneration in the outflowing plasma (similarly to the field generation
by LAEMW of laser-plasma interactions) and mixing with the upstream plasma.

</DOC>
<DOC>
<DOCNO> 13871 </DOCNO>
The 3d-electron states in LaCoO3


  Three fundamentally different electronic structures for 3d electron states in
LaCoO3, discussed in the current literature, have been presented. We are in
favour of the localized electron atomic- like approach that yields the discrete
energy spectrum associated with the atomic-like states of the Co3+ ions in
contrary to the continouos energy spectrum yielded by band theories. In our
atomic-like approach the d electrons form the highly-correlated system 3dn
described by S=2 and L=2. PACS No: 71.70.Ej : 75.10.Dg : 73.30.-m; Keywords:
Mott insulators, electronic structure, crystal field, LaCoO3 Phys.Rev.Lett.
03-08-2000

</DOC>
<DOC>
<DOCNO> 85194 </DOCNO>
Wiggly Strings in Linearized Brans-Dicke Gravity


  The metric around a wiggly cosmic string is calculated in the linear
approximation of Brans-Dicke theory of gravitation. The equations of motion for
relativistic and non-relativistic particles in this metric are obtained.
 Light propagation is also studied and it is shown that photon trajectories can
be bounded.

</DOC>
<DOC>
<DOCNO> 80994 </DOCNO>
Matrix Distributed Processing and FermiQCD


  Matrix Distributed Processing is a collection of classes and functions
written in C++ for fast development of efficient parallel algorithms for the
most general lattice/grid application. FermiQCD is an Object Oriented Lattice
QCD application of MDP, under development at Fermilab.

</DOC>
<DOC>
<DOCNO> 174614 </DOCNO>
Evidence for Thermal Equilibration in Multifragmentation Reactions


  The production of nuclear bremsstrahlung photons (E$_{\gamma}>$ 30 MeV) has
been studied in inclusive and exclusive measurements in four heavy-ion
reactions at 60{\it A} MeV. The measured photon spectra, angular distributions
and multiplicities indicate that a significant part of the hard-photons are
emitted in secondary nucleon-nucleon collisions from a thermally equilibrated
system. The observation of the thermal component in multi-fragment
$^{36}$Ar+$^{197}$Au reactions suggests that the breakup of the thermalized
source produced in this system occurs on a rather long time-scale.

</DOC>
<DOC>
<DOCNO> 117580 </DOCNO>
Sunyaev-Zel'dovich Surveys: Analytic treatment of cluster detection


  Thanks to advances in detector technology and observing techniques, true
Sunyaev-Zel'dovich (SZ) surveys will soon become a reality. This opens up a new
window into the Universe, in many ways analogous to the X-ray band and
inherently well-adapted to reaching high redshifts. I discuss the nature,
abundance and redshift distributions of objects detectable in ground-based
searches with state-of-the-art technology. An advantage of the SZ approach is
that the total SZ flux density depends only on the thermal energy of the
intracluster gas and not on its spatial or temperature structure, in contrast
to the X-ray luminosity. Because ground-based surveys will be characterized by
arcminute angular resolution, they will resolve a large fraction of the cluster
population. I quantify the resulting consequences for the cluster selection
function; these include less efficient cluster detection compared to idealized
point sources and corresponding steeper integrated source counts. This implies,
contrary to expectations based on a point source approximation, that deep
surveys are better than wide ones in terms of maximizing the number of detected
objects. At a given flux density sensitivity and angular resolution, searches
at millimeter wavelengths (bolometers) are more efficient than centimeter
searches (radio), due to the form of the SZ spectrum. Possible ground-based
surveys could discover up to $\sim 100$ clusters per square degree at a
wavelength of 2 mm and $\sim 10$/sq. deg. at 1 cm, modeling clusters as a
simple self-similar population.

</DOC>
<DOC>
<DOCNO> 102722 </DOCNO>
Noninvertibility, semisupermanifolds and categories regularization


  The categories with noninvertible morphisms are studied analogously to the
semisupermanifolds with noninvertible transition functions. The concepts of
regular n-cycles, obstruction and the regularization procedure are introduced
and investigated. It is shown that the regularization of a category with
nonivertible morphisms and obstruction form a 2-category. The generalization of
functors, Yang-Baxter equation, (co-) algebras, (co-) modules and some related
structures to the regular case is given.

</DOC>
<DOC>
<DOCNO> 119487 </DOCNO>
MAXIMA-1: A Measurement of the Cosmic Microwave Background Anisotropy on


  We present a map and an angular power spectrum of the anisotropy of the
cosmic microwave background (CMB) from the first flight of MAXIMA. MAXIMA is a
balloon-borne experiment with an array of 16 bolometric photometers operated at
100 mK. MAXIMA observed a 124 square degrees region of the sky with 10
arcminute resolution at frequencies of 150, 240 and 410 GHz. The data were
calibrated using in-flight measurements of the CMB dipole anisotropy. A map of
the CMB anisotropy was produced from three 150 and one 240 GHz photometer
without need for foreground subtractions. Analysis of this CMB map yields a
power spectrum for the CMB anisotropy over the range 36 < l < 785. The spectrum
shows a peak with an amplitude of 78 +/- 6 micro-Kelvin at l ~ 220 and an
amplitude varying between ~40 micro-Kelvin and ~50 micro-Kelvin for 400 < l <
785.

</DOC>
<DOC>
<DOCNO> 70684 </DOCNO>
Bottom-up thermalization in heavy ion collisions


  We describe how thermalization occurs in heavy ion collisions in the
framework of perturbative QCD. When the saturation scale $Q_s$ is large
compared to $\Lambda_{QCD}$, thermalization takes place during a time of order
$\alpha^{-13/5}Q_s^{-1}$ and the maximal temperature achieved is
$\alpha^{2/5}Q_s$.

</DOC>
<DOC>
<DOCNO> 174495 </DOCNO>
On the reliability of the theoretical internal conversion coefficients


  Possible sources of uncertainties in the calculations of the internal
conversion coefficients are studied. The uncertainties induced by them are
estimated.

</DOC>
<DOC>
<DOCNO> 12758 </DOCNO>
Multi-scale modeling of poly(isoprene) melts


  Atomistic (atom-scale) and coarse-grained (meso-scale) simulations of
structure and dynamics of poly-isoprene melts are compared. The local structure
and chain packing is mainly determined by the atomistic details of the polymer
architecture. The large-time dynamics encountered in NMR experiments can be
explained by meso-scale simulations including stiffness. The connecting link
between the two scales is the stiffness which, although being a local property,
influences strongly even the long-timescale dynamics. The standard reptation
scenario fails to explain the observed dynamics. We propose strong reptation as
a modified reptation scenario in which the local Rouse motion is absent.

</DOC>
<DOC>
<DOCNO> 68365 </DOCNO>
The east-west effect for atmospheric neutrinos


  The atmospheric neutrino fluxes observed by underground detectors are not
symmetric for rotations around the vertical axis. The flux is largest
(smallest) for the nu's traveling toward east (west). This asymmetry is the
result of the effects of the geomagnetic field on the primary cosmic rays and
on their showers. The size of the asymmetry is to a good approximation
independent from the existence of neutrino oscillations, and can in principle
be predicted without any ambiguity due to existence of unknown new physics. We
show that there is an interesting hint of discrepancy between the experimental
measurement of the east-west asymmetry by Super-Kamiokande and the existing
theoretical predictions. We argue that the discrepancy is a real effect caused
by the neglect, in the existing calculations, of the bending of the charged
secondary particles (in particular of the muons) in the cosmic ray showers. The
inclusion of this effect in the calculation gives results in quantitative
agreeement with the data. We comment on the implications of this result for the
study of neutrino oscillations.

</DOC>
<DOC>
<DOCNO> 100231 </DOCNO>
A formula for Gau{\ss}-Manin determinants


  We give an explicit formula for the determinant of the Gau{\ss}-Manin
connection for an irregular connection on a Zariski open set of the projective
line $\P^1_K$ over a function field $K$ over a field $k$ of characteristic
zero.

</DOC>
<DOC>
<DOCNO> 122411 </DOCNO>
Molecular hydrogen abundance in the dust-free damped Ly-alpha galaxy at


  New results from the search for H2 absorption in the damped Ly-alpha galaxy
at redshift z = 3.4 toward QSO 0000-2620 (z_em = 4.1) are reported. The
high-resolution (lambda/Delta lambda = 48,000) spectra of Q0000-2620 were
obtained using the Ultraviolet - Visual Echelle Spectrograph (UVES) on the 8.2m
ESO Kueyen telescope. The ortho-H2 column density is found to be N(J=1) = (5.55
+/- 1.35) 10^{13} cm^{-2} (2sigma C.L.). The combination of N(J=1) with the
limits available for other low rotational levels restricts the excitation
temperature T_ex in the range (290-540) K. This gives the total H2 column
density of N(H2) = (8.75 +/- 1.25) 10^{13} cm^{-2} and the corresponding
fraction of hydrogen atoms bound in molecules of f(H2) = (6.8 +/- 2.0) 10^{-8}.

</DOC>
<DOC>
<DOCNO> 120516 </DOCNO>
Can gravitational waves be detected in quasar microlensing?


  Studies of the lensed quasar ${\rm Q}0957+561 {\rm A,B}$ have shown evidence
for microlensing in the brightness history of the quasar images. It had been
suggested that a frequency offset between the brightness fluctuations in each
of the two images might possibly be caused by gravitational radiation generated
by a massive black hole binary at the center of the lensing galaxy. This paper
demonstrates that the fluctuations produced by such a source of gravitational
waves will be too small to account for the observed frequency offsets.

</DOC>
<DOC>
<DOCNO> 11686 </DOCNO>
Nagel scaling and relaxation in the kinetic Ising model on a n-isotopic


  The kinetic Ising model on a n-isotopic chain is considered in the framework
of Glauber dynamics. The chain is composed of N segments with n sites, each one
occupied by a different isotope. Due to the isotopic mass difference, the n
spins in each segment have different relaxation times in the absence of the
interactions, and consequently the dynamics of the system is governed by
multiple relaxation mechanisms. The solution is obtained in closed form for
arbitrary n, by reducing the problem to a set of n coupled equations, and it is
shown rigorously that the critical exponent z is equal to 2. Explicit results
are obtained numerically for any temperature and it is also shown that the
dynamic susceptibility satisfies the new scaling (Nagel scaling) proposed for
glass-forming liquids. This is in agreement with our recent results (L. L.
Goncalves, M. Lopez de Haro, J. Taguena-Martinez and R. B. Stinchcombe, Phys.
Rev. Lett. 84, 1507 (2000)), which relate this new scaling function to multiple
relaxation processes.

</DOC>
<DOC>
<DOCNO> 99780 </DOCNO>
Quantization of bending deformations of polygons in Euclidean space,


  We quantize the bending deformations of n-gon linkages by linearizing the
bending fields at a degenerate n-gon to get a representation of the Malcev Lie
algebra of the pure braid group. This linearization yields a flat connection on
the space of n distinct points on the complex line. We show that the monodromy
is (essentially) the Gassner representation.

</DOC>
<DOC>
<DOCNO> 99540 </DOCNO>
On the Splitting Type of an Equivariant Vector Bundle over a Toric


  From the work of Lian, Liu, and Yau on "Mirror Principle", in the explicit
computation of the Euler data $Q=\{Q_0, Q_1, ... \}$ for an equivariant
concavex bundle ${\cal E}$ over a toric manifold, there are two places the
structure of the bundle comes into play: (1) the multiplicative characteric
class $Q_0$ of $V$ one starts with, and (2) the splitting type of ${\cal E}$.
Equivariant bundles over a toric manifold has been classified by Kaneyama,
using data related to the linearization of the toric action on the base toric
manifold. In this article, we relate the splitting type of ${\cal E}$ to the
classifying data of Kaneyama. From these relations, we compute the splitting
type of a couple of nonsplittable equivariant vector bundles over toric
manifolds that may be of interest to string theory and mirror symmetry. A code
in Mathematica that carries out the computation of some of these examples is
attached.

</DOC>
<DOC>
<DOCNO> 8018 </DOCNO>
Hall effect and conduction anisotropy in the organic conductor TMTSF2PF6


  Long missing basic experiments in the normal phase of the anisotropic
electron system of TMTSF2PF6 were performed. Both the Hall effect and the
ab'-plane conduction anisotropy are directly addressing the unconventional
electrical properties of this Bechgaard salt. We found that the dramatic
reduction of the carrier density deduced from recent optical data is not
reflected in an enhanced Hall-resistance. The pressure- and temperature
dependence of the b'-direction resitivity reveal isotropic relaxation time and
do not require explanations beyond the Fermi liquid theory. Our results allow a
coherent-diffusive transition in the interchain carrier propagation, however
the possible crossover to Luttinger liquid behavior is placed to an energy
scale above room temperature.

</DOC>
<DOC>
<DOCNO> 169737 </DOCNO>
Simple Proof of Security of the BB84 Quantum Key Distribution Protocol


  We prove the security of the 1984 protocol of Bennett and Brassard (BB84) for
quantum key distribution. We first give a key distribution protocol based on
entanglement purification, which can be proven secure using methods from Lo and
Chau's proof of security for a similar protocol. We then show that the security
of this protocol implies the security of BB84. The entanglement-purification
based protocol uses Calderbank-Shor-Steane (CSS) codes, and properties of these
codes are used to remove the use of quantum computation from the Lo-Chau
protocol.

</DOC>
<DOC>
<DOCNO> 101864 </DOCNO>
On the topological entropy of an optical Hamiltonian flow


  In this article we prove two formulas for the topological entropy of an
F-optical Hamiltonian flow induced by a C^{\infty} Hamiltonian, where F is a
Lagrangian distribution. In these formulas, we calculate the topological
entropy as the exponential growth rate of the average of the determinant of the
differential of the flow, restricted to the Lagrangian distribution or to a
proper modification.

</DOC>
<DOC>
<DOCNO> 170302 </DOCNO>
The Backwards-Time Interpretation of Quantum Mechanics - Revisited With


  The classic paper of Clauser et al proved that Bell's Theorem experiments
rule out all theories of physics which assume locality, time-forwards causality
and the existence of an objective real world. The Backwards-Time Interpretation
(BTI) tries to recover realism and locality by permitting backwards time
causality. BTI should permit dramatic simplification of the assumptions or
axioms of physics, but requires new work in fundamental mathematics, such as
new tools for the "closure of turbulence," the derivation of statistics
generated by ODE or PDE.
  Recent events like the Delayed Choice Quantum Eraser experiment of Kim, Shih
et al have increased mainstream interest in the possibility of backwards
causality. The Backwards Time Quantum Teleportation (BTQT) experiment will take
this further. True backwards time communication channels (BTCC) are absolutely
impossible in most formulations of quantum theory but only almost impossible in
the BTI formulation. This paper discusses BTQT, the issue of backwards
causality in different versions of quantum theory and new mathematical
developments. It defines a new object, the "entropy matrix," which leads to
closure of turbulence for PDE systems. Predictions of a common toy field theory
(real phi-3 QFT) are reproduced by the corresponding PDE model combined with a
new model of the micro/macro interface (2M/M).

</DOC>
<DOC>
<DOCNO> 116792 </DOCNO>
Morphometry of Spatial Patterns


  Minkowski functionals constitute a family of order parameters which
discriminate spatial patterns according to size, shape and connectivity. Here
we point out, that these scalar descriptors can be complemented by
vector-valued curvature measures also known as Quermass vectors. Using examples
of galaxy clusters, we demonstrate that the Quermass vectors provide additional
morphological information on directional features and symmetries displayed by
spatial data.

</DOC>
<DOC>
<DOCNO> 102062 </DOCNO>
Dissipation in Turbulent Solutions of 2-D Euler


  We establish local balance equations for smooth functions of the vorticity in
the DiPerna-Majda weak solutions of 2D incompressible Euler, analogous to the
balance proved by Duchon and Robert for kinetic energy in 3D. The anomalous
term or defect distribution therein corresponds to the ``enstrophy cascade'' of
2D turbulence. It is used to define a rather natural notion of ``dissipative
Euler solution'' in 2D. However, we show that the DiPerna-Majda solutions with
vorticity in $L^p$ for $p>2$ are conservative and have zero defect. Instead, we
must seek an alternative approach to dissipative solutions in 2D. If we assume
an upper bound on the energy spectrum of 2D incompressible Navier-Stokes
solutions by the Kraichnan-Batchelor $k^{-3}$ spectrum, uniformly for high
Reynolds number, then we show that the zero viscosity limits of the
Navier-Stokes solutions exist, with vorticities in the zero-index Besov space
$B^{0,\infty}_2$, and that these give a weak solution of the 2D incompressible
Euler equations. We conjecture that for this class of weak solutions enstrophy
dissipation may indeed occur, in a sense which is made precise.

</DOC>
<DOC>
<DOCNO> 101191 </DOCNO>
Oscillatory integral operators with low-order degeneracies


  Sharp L^2 estimates for oscillatory integral operators and Fourier integral
operators associated with canonical relations having two-sided cusp or
one-sided swallowtail singularities are obtained.

</DOC>
<DOC>
<DOCNO> 40386 </DOCNO>
Two-Loop Correction to Bhabha Scattering


  We present the two-loop virtual QED corrections to e^+ e^- to mu^+ mu^- and
Bhabha scattering in dimensional regularization. The results are expressed in
terms of polylogarithms. The form of the infrared divergences agrees with
previous expectations. These results are a crucial ingredient in the complete
next-to-next-to-leading order QED corrections to these processes. A future
application will be to reduce theoretical uncertainties associated with
luminosity measurements at e^+ e^- colliders. The calculation also tests
methods that may be applied to analogous QCD processes.

</DOC>
<DOC>
<DOCNO> 40144 </DOCNO>
Standard Model correlations between K -> \pi \nu \bar\nu decays and


  Including the recent preliminary results of BaBar and BELLE experiments, we
update the currently allowed intervals for various CKM parameters: $\bar\rho$,
$\bar\eta$, $\sin2\beta$, $\sin2\alpha$, $\sin^2\gamma$. We also update the SM
prediction for the rates of the $K_L \to \pi^0 \nu \bar\nu$ and $K^+ \to \pi^+
\nu \bar\nu$ decays, their ratio $a_{\pi \nu \bar\nu}$, as well as for certain
observables related to $B$ Physics like the CP asymmetries $a_{\psi K_S}$ in
$B^0_d \to J/\psi K_S$ and $a_{\psi \phi}$ in $B^0_s \to J/\psi \phi$ or the
mass differences $\Delta m_q$ ($q=d,s$) in the $B^0_q-\bar B^0_q$ systems. We
investigate the correlations between them. The strongest correlations are
between i) $a_{\pi \nu \bar\nu}$ and $a_{\psi K_S}$, ii) $\BR(K^+ \to \pi^+ \nu
\bar\nu)$ and $\Delta m_d/\Delta m_s$ and iii) $\BR(K_L \to \pi^0 \nu \bar\nu)$
and $a_{\psi \phi}$. These correlations are likely to be violated in the
presence of New Physics and therefore provide stringent tests of the Standard
Model.

</DOC>
<DOC>
<DOCNO> 151466 </DOCNO>
Manifestly supersymmetric M-theory


  In this paper, the low-energy effective dynamics of M-theory,
eleven-dimensional supergravity, is taken off-shell in a manifestly
supersymmetric formulation. We show that a previously proposed relaxation of
the superspace torsion constraints does indeed accommodate a current
supermultiplet which lifts the equations of motion corresponding to the
ordinary second order derivative supergravity lagrangian. Whether the auxiliary
fields obtained this way can be used to construct an off-shell lagrangian is
not yet known. We comment on the relation and application of this completely
general formalism to higher-derivative (R^4) corrections. Some details of the
calculation are saved for a later publication.

</DOC>
<DOC>
<DOCNO> 12082 </DOCNO>
Is the Quantum Melting of a Polaron Wigner Crystal an


  On examining the stability of a Wigner Crystal (WC) in an ionic dielectric,
two competitive effects due to Polaron formation are found to be important: (i)
the screening of the Coulomb forces which destabilizes the crystal, compensated
by (ii) the increase of the carrier mass (polaron mass). The quantum melting of
the Polaron Wigner Crystal (PWC) is examined. By calculating the quantum
fluctuations of both the electrons and the polarization, we show that there is
a competition between the dissociation of the Polarons at the
insulator-to-metal transition (IMT), and a melting towards a polaron liquid. We
find that at strong coupling ($\alpha > \alpha^*$), a liquid state of polarons
cannot exist, and the IMT is driven by polaron dissociation. Next, we show that
the dipolar interactions between localized polarons are responsible for a
phonon instability of the PWC as the density increases. This provides a new
mechanism for the IMT in doped dielectrics. Examining the sign of the
dielectric constant of the PWC, we conjecture that such an instability could
yield an Insulator-to-Superconductor transition.

</DOC>
<DOC>
<DOCNO> 14097 </DOCNO>
Quantum Spin Fluctuations as a Source of Long-Range Proximity Effects in


  We show that quantum spin fluctuations in inhomogeneous ferromagnets
drastically affect the Andreev reflection of electrons and holes at a
ferromagnet-superconductor interface. As a result a strong long-range proximity
effect appears, associated with electron-hole spin triplet correlations and
persisting on a lenght scale typical for non-magnetic materials, but
anomalously large for ferromagnets.

</DOC>
<DOC>
<DOCNO> 101073 </DOCNO>
Vanishing of the Kontsevich integrals of the wheels


  We prove that the Kontsevich integrals (in the sense of the formality
theorem) of all even wheels are equal to zero. We deduce this theorem from the
result of \cite{FSh} on the deformation quantization with traces.

</DOC>
<DOC>
<DOCNO> 67698 </DOCNO>
Diffraction: A New Approach


  A phenomenological model of hard diffraction is presented, in which the
structure of the Pomeron is derived from the structure of the parent hadron.
Predictions for diffractive deep inelastic scattering are compared with data.

</DOC>
<DOC>
<DOCNO> 99478 </DOCNO>
Brownian motion on a smash line


  Brownian motion on a smash line algebra (a smash or braided version of the
algebra resulting by tensoring the real line and the generalized paragrassmann
line algebras), is constructed by means of its Hopf algebraic structure.
Further, statistical moments, non stationary generalizations and its diffusion
limit are also studied. The ensuing diffusion equation posseses triangular
matrix realizations.

</DOC>
<DOC>
<DOCNO> 101492 </DOCNO>
Approximating $L^2$ torsion on amenable covering spaces


  It was pointed out to us that the proof of a crucial lemma (Lemma 5.3) in the
paper is incorrect. Thus the approximation theorem (Theorem 0.1) for L^2
torsion of an amenable covering of a finite simplicial complex remains
unproved.
  However, results and proofs of the first four sections (in particular, the
approximation theorem (Theorem 0.3) for the spectral density function of an
amenable covering) are correct.

</DOC>
<DOC>
<DOCNO> 123137 </DOCNO>
Discriminating weak lensing from intrinsic spin correlations using the


  The distortion field defined by the ellipticities of galaxy shapes projected
on the sky can be uniquely decomposed into a gradient and a curl component. If
the observed ellipticities are induced by weak gravitational lensing, then the
distortion field is curl free. Here we show that, in contrast, the distortion
field resulting from intrinsic spin alignments is not curl free. This provides
a powerful discriminant between lensing and intrinsic contributions to observed
ellipticity correlations. We also show how these contributions can be
disentangled statistically from the ellipticity correlations or computed
locally from circular integrals of the ellipticity field. This allows for an
unambiguous detection of intrinsic galaxy alignments in the data. When the
distortions are dominated by lensing, as occurs at high redshifts, the
decomposition provides a valuable tool for understanding properties of the
noise and systematic errors. These techniques can be applied equally well to
the polarization of the microwave background, where it can be used to separate
curl-free scalar perturbations from those produced by gravity waves or defects.

</DOC>
<DOC>
<DOCNO> 118788 </DOCNO>
GENIUS: the first real-time detector for solar pp-neutrinos?


  The GENIUS project is a proposal for a large supersensitive Germanium
detector system for WIMP and double beta decay searches with a much increased
sensitivity relative to existing and other future experiments. In this paper,
the possibility to detect low energy solar neutrinos with GENIUS in real-time
through elastic neutrino-electron scattering is studied.

</DOC>
<DOC>
<DOCNO> 151199 </DOCNO>
Dual expansions of N=4 super Yang-Mills theory via IIB superstring


  We examine the dual correspondence between holographic IIB superstring theory
and N=4 super Yang-Mills theory at finite values of the coupling constants. In
particular we analyze a field theory strong-coupling expansion which is the
S-dual of the planar expansion. This expansion arises naturally as the AdS/CFT
dual of the IIB superstring scattering amplitudes given a genus truncation
property due to modular invariance. The space-time structure of the
contributions to the field theory four-point correlation functions obtained
from the IIB scattering elements is investigated in the example of the product
of four conserved stress tensors, and is expressed as an infinite sum of field
theory triangle integrals. The OPE structure of these contributions to the
stress tensor four-point function is analyzed and shown not to give rise to any
poles. Quantization of the string in the background of a five-form field
strength is performed through a covariantized background field approach, and
relations to the N=4 topological string are found.

</DOC>
<DOC>
<DOCNO> 72290 </DOCNO>
Abelian Monopole and Center Vortex Views at the Multi-Instanton Gas


  We consider full non-Abelian, Abelian and center projected lattice field
configurations built up from random instanton gas configurations in the
continuum. We study the instanton contribution to the $\bar{Q}Q$ force with
respect to ({\it i}) instanton density dependence, ({\it ii}) Casimir scaling
and ({\it iii}) whether various versions of Abelian dominance hold. We check
that the dilute gas formulation for the interaction potential gives an reliable
approximation only for densities small compared to the phenomenological value.
We find that Casimir scaling does not hold, confirming earlier statements in
the literature. We show that the lattice used to discretize the instanton gas
configurations has to be sufficiently coarse ($a \approx 2\bar{\rho}$ compared
with the instanton size $\bar{\rho}$) such that maximal Abelian gauge
projection and center projection as well as the monopole gas contribution to
the $\bar{Q}Q$ force reproduce the non-Abelian instanton-mediated force in the
intermediate range of linear quasi-confinement. We demonstrate that monopole
clustering also depends critically on the discretization scale confirming
earlier findings based on monopole blocking.

</DOC>
<DOC>
<DOCNO> 13384 </DOCNO>
Fokker-Planck equation of distributions of financial returns and power


  Our purpose is to relate the Fokker-Planck formalism proposed by [Friedrich
et al., Phys. Rev. Lett. 84, 5224 (2000)] for the distribution of stock market
returns to the empirically well-established power law distribution with an
exponent in the range 3-5. We show how to use Friedrich et al.'s formalism to
predict that the distribution of returns is indeed asymptotically a power law
with an exponent mu that can be determined from the Kramers-Moyal coefficients
determined by Friedrich et al. However, with their values determined for the
U.S. dollar-German mark exchange rates, the exponent mu predicted from their
theory is found around 12, in disagreement with the often-quoted value between
3 and 5. This could be explained by the fact that the large asymptotic value of
12 does not apply to real data that lie still far from the stationary state of
the Fokker-Planck description. Another possibility is that power laws are
inadequate. The mechanism for the power law is based on the presence of
multiplicative noise across time-scales, which is different from the
multiplicative noise at fixed time-scales implicit in the ARCH models developed
in the Finance literature.

</DOC>
<DOC>
<DOCNO> 72072 </DOCNO>
Nucleon Polarisabilities from Compton Scattering on the Deuteron


  An analytic calculation of the differential cross section for elastic Compton
scattering on the deuteron at photon energies \omega in the range of 25-50 MeV
is presented to next-to-next-to-leading order, i.e. to an accuracy of \sim 3%.
The calculation is model-independent and performed in the low energy nuclear
Effective Field Theory without dynamical pions. The iso-scalar, scalar electric
and magnetic nucleon polarisabilities \alpha_0 and \beta_0 enter as free
parameters with a theoretical uncertainty of about 20%. Using data at
$\omega_{Lab}=49 MeV$ we find $\alpha_0=8.4\pm 3.0(exp)\pm 1.7(theor)$,
$\beta_0=8.9\pm 3.9(exp)\pm 1.8(theor)$, each in units of $10^{-4} fm^3$. With
the experimental constraint for the iso-scalar Baldin sum rule,
$\alpha_0=7.2\pm 2.1(exp)\pm 1.6(theor)$, $\beta_0=6.9\mp 2.1(exp)\mp
1.6(theor)$. A more accurate result can be achieved by: (i) better experimental
data, and (ii) a higher order theoretical calculation including contributions
from a couple of so far undetermined four-nucleon-two-photon operators.

</DOC>
<DOC>
<DOCNO> 69097 </DOCNO>
$\omega-\rho$ Mixing and the $\omega\to\pi\pi\gamma$ Decay


  We reexamine the $\omega \to \pi^{0} \pi^{0} \gamma $ decay, adding the
effect of $\omega-\rho$ mixing to the amplitude calculated with the aid of
chiral perturbation theory and vector meson dominance. We predict the neutral
decay to occur with a width of $\Gamma($\omega \to \pi^{0} \pi^{0} \gamma $)
=(390\pm96) {\rm eV}$ and also analyze the effect of the $\omega-\rho$ mixing
on the $\Gamma($\omega \to \pi^{0} \pi^{0} \gamma $)/ \Gamma($\omega \to
\pi^{+} \pi^{-} \gamma $)$ ratio. Several remarks on the effect of
$\omega-\rho$ mixing on certain radiative decays of vector mesons are
presented.

</DOC>
<DOC>
<DOCNO> 8283 </DOCNO>
Magnetic instability of a two-dimensional Anderson non-Fermi liquid


  We show that in the Anderson model for a two-dimensional non-Fermi liquid a
magnetic instability can lead to the itinerant electron ferromagnetism. The
critical temperature and the susceptibility of the paramagnetic phase have been
analytically calculated. The usual Fermi behaviour is re-obtained taking the
anomalous exponent to be zero.

</DOC>
<DOC>
<DOCNO> 70935 </DOCNO>
Baryonic Q-balls as dark matter


  Supersymmetric extensions of the Standard Model predict the existence of
Q-balls, some of which can be entirely stable. Affleck-Dine baryogenesis can
result in a copious production of stable baryonic Q-balls, which can presently
exist as a form of dark matter.

</DOC>
<DOC>
<DOCNO> 39789 </DOCNO>
Strong and electromagnetic decays of p-wave heavy baryons $\Lambda_{c1},


  We first calculate the binding energy, the pionic and electromagnetic couping
constants of the lowest lying p-wave heavy baryon doublet $\Lambda_{c1}$,
$\Lambda_{c1}^*$ in the leading order of the heavy quark expansion. Then we
calculate the two-body decay widths with these couplings and compare our
results with other approaches. Our results are $\Gamma (\Lambda_{c1}\to
\Sigma_c \pi, \Sigma_c \gamma, \Sigma^*_c \gamma) =2.7, 0.011, 0.001$ MeV and
$\Gamma (\Lambda^*_{c1}\to \Sigma_c \pi, \Sigma_c \gamma, \Sigma^*_c \gamma,
\Lambda_{c1} \gamma) =33, 5, 6, 0.014$ keV respectively. We find $\Lambda_{c1},
\Lambda^*_{c1}\to \Lambda_c \gamma$ is strictly forbidden in the leading order
of the heavy quark expansion. At the order of ${\cal O} (1/m_c)$ their widths
are $36, 48$ keV respectively.

</DOC>
<DOC>
<DOCNO> 116600 </DOCNO>
Resampling Method For Unsupervised Estimation Of Cluster Validity


  We introduce a method for validation of results obtained by clustering
analysis of data. The method is based on resampling the available data. A
figure of merit that measures the stability of clustering solutions against
resampling is introduced. Clusters which are stable against resampling give
rise to local maxima of this figure of merit. This is presented first for a
one-dimensional data set, for which an analytic approximation for the figure of
merit is derived and compared with numerical measurements. Next, the
applicability of the method is demonstrated for higher dimensional data,
including gene microarray expression data.

</DOC>
<DOC>
<DOCNO> 84772 </DOCNO>
Kerr-Schild Symmetries


  We study continuous groups of generalized Kerr-Schild transformations and the
vector fields that generate them in any n-dimensional manifold with a
Lorentzian metric. We prove that all these vector fields can be intrinsically
characterized and that they constitute a Lie algebra if the null deformation
direction is fixed. The properties of these Lie algebras are briefly analyzed
and we show that they are generically finite-dimensional but that they may have
infinite dimension in some relevant situations. The most general vector fields
of the above type are explicitly constructed for the following cases: any
two-dimensional metric, the general spherically symmetric metric and
deformation direction, and the flat metric with parallel or cylindrical
deformation directions.

</DOC>
<DOC>
<DOCNO> 120918 </DOCNO>
Black Holes Must Die


  In light of recent evidence suggesting a nonzero present-day cosmological
constant, Adams, Mbonye, & Laughlin (1999) have considered the evolution of
black holes in the presence of vacuum energy. Using the assumption that Lambda
remains constant with time, and a conjecture based on a paper by Mallett
(1986), they reach the remarkable conclusion that black holes with current mass
greater than about 2*10^(-9) Msun will not Hawking evaporate in the distant
future, but will instead absorb vacuum energy and grow to roughly the de Sitter
horizon size. In this letter we reexamine black hole evaporation in the
presence of vacuum energy, and find instead that all known black holes will
eventually evaporate.

</DOC>
<DOC>
<DOCNO> 99689 </DOCNO>
Random triangle problem: geometrical approach


  Classical problem of random triangle in square is solved by simple and
transparent geometrical method.

</DOC>
<DOC>
<DOCNO> 122629 </DOCNO>
A shock-excited OH maser in a post-AGB envelope ?


  We have observed a sample of OH 1612-MHz masing objects in all four OH
ground--state transitions with the Australia Telescope Compact Array. One
likely post-AGB object is found to emit in the 1612-MHz, 1665-MHz and 1720-MHz
transitions. We discuss the evidence that this object may be an early post-AGB
object and the possibility for such a circumstellar envelope to harbour a
1720-MHz maser. We argue that during a very brief period, just after the star
has left the thermally-pulsing phase of the AGB and the wind velocity starts to
increase, post-AGB objects might show \sath emission. The best objects to
search for such emission would be those that are masing at 1612 MHz and 1665
MHz, but not at 1667 MHz nor in the 22-GHz H2O transition.

</DOC>
<DOC>
<DOCNO> 119704 </DOCNO>
Poststarburst Models of LINERs


  Since the discovery of low-ionization nuclear emission-line regions in many
galaxies (LINERs), it has been recognized that they constitute a class of
active galactic nuclei (AGNs) which are thought to be powered by gas accretion
onto a central, supermassive black hole. LINERs are observed in approximately
one third of galaxies in the local universe and it has been often thought that
they harbor an AGN-like central engine with moderate activity. However, some
LINERs show no direct evidence for AGNs such as broad emission lines, radio
jets, hard X-ray emission, spectral energy distributions which are inconsistent
with starlight, and so on. For such LINERs (a subset of type 2 LINERs), we
present new poststarburst models which explain some of their most important
optical narrow emission-line ratios. In these models, the ionization sources
are planetary nebula nuclei (PNNs) with temperature of ~ 10^5 K which appear in
the late-phase evolution of intermediate-mass stars with mass between ~ 3
M_solar and ~ 6 M_solar. Such PNNs left in a typical starburst nucleus can
produce an Halpha luminosity of L(Halpha) ~ 10^38 ergs s^-1 for typical
poststarburst LINERs and ~ 10^39 ergs s^-1 only in exceptionally bright cases.
The PNN phase lasts until the death of the lowest-mass stars formed in the
starburst, which is ~ 5 x 10^8 yr for an assumed lower limit of the initial
mass function of 3 M_solar. This long duration appears consistent with the
observed higher frequency of occurrence of LINERs if every galaxy could
experience the starburst activity several times in its life. We therefore
propose that some LINERs which show no direct evidence for AGNs may be
poststarburst nuclei powered by a cluster of PNNs.

</DOC>
<DOC>
<DOCNO> 122929 </DOCNO>
The Effect of Formation Redshifts on the Cluster Mass-Temperature


  I employ an ensemble of hydrodynamical simulations and the XSPEC MEKAL
emission model to reproduce observable spectral and flux-weighted temperatures
for 24 clusters. Each cluster is imaged at 16 points in its history, which
allows the investigation of evolutionary effects on the mass-temperature
relation. In the zero redshift scaling relations, I find no evidence for a
relationship between cluster temperature and formation epoch for those clusters
which acquired 75% of their final mass since a redshift of 0.6. This result
holds for both observable and intrinsic intracluster medium temperatures, and
implies that halo formation epochs are not an important variable in analysis of
observable cluster temperature functions.

</DOC>
<DOC>
<DOCNO> 10849 </DOCNO>
Small worlds


  Small world networks have recently recieved considerable attention. The most
basic version of such a network starts from a ring lattice with $L$ vertices,
where a vertex is connected to its $k$ nearest neighbours on each side by an
undirected adge. In addition, shortcuts are added to the graph with probability
$p$ per shortcut. A typical quantity computed to describe the graph is the
average shortest path between two vertices. Here, we analyze a continuous
model, in which a random number of chords are uniformly and independently
superimposed as shortcuts on a circle with circumference $L$. We prove a
distributional approximation for the distance between two randomly chosen
points, when the expected number of shortcuts is large, and we give a bound on
the order of the error, in terms of total variation distance. This distribution
differs, in both location and spread, from that suggested by Newman, Moore and
Watts (1999), though it agrees to the coarsest order. We also prove analogous
results in higher dimensions; here, the reduction in the typical distance
between pairs of points due to shortcuts is less pronounced than in one
dimension.

</DOC>
<DOC>
<DOCNO> 84812 </DOCNO>
Cerenkov radiation and scalar stars


  We explore the possibility that a charged particle moving in the
gravitational field generated by a scalar star could radiate energy via a
recently proposed gravitational \v{C}erenkov mechanism. We numerically prove
that this is not possible for stable boson stars. We also show that soliton
stars could have \v{C}erenkov radiation for particular values of the boson
mass, although diluteness of the star grows and actual observational
possibility decreases for the more usually discussed boson masses. These
conclusions diminish, although do not completely rule out, the observational
possibility of actually detecting scalar stars using this mechanism, and lead
us to consider other forms, like gravitational lensing.

</DOC>
<DOC>
<DOCNO> 118868 </DOCNO>
Source Reconstruction as an Inverse Problem


  Inverse Problem techniques offer powerful tools which deal naturally with
marginal data and asymmetric or strongly smoothing kernels, in cases where
parameter-fitting methods may be used only with some caution. Although they are
typically subject to some bias, they can invert data without requiring one to
assume a particular model for the source. The Backus-Gilbert method in
particular concentrates on the tradeoff between resolution and stability, and
allows one to select an optimal compromise between them. We use these tools to
analyse the problem of reconstructing features of the source star in a
microlensing event, show that it should be possible to obtain useful
information about the star with reasonably obtainable data, and note that the
quality of the reconstruction is more sensitive to the number of data points
than to the quality of individual ones.

</DOC>
<DOC>
<DOCNO> 69117 </DOCNO>
Topological Inflation in Supergravity


  We investigate a topological inflation model in supergravity. By means of
numerical simulations, it is confirmed that topological inflation can take
place in supergravity. We also show that the condition for successful inflation
depends not only on the vacuum-expectation value (VEV) of inflaton field but
also on the form of its K\"ahler potential. In fact, it is found that the
required VEV of the inflaton $\phi$ can be as small as $<\phi > \simeq 1 \times
M_G$, where $M_{G}$ is the gravitational scale.

</DOC>
<DOC>
<DOCNO> 151584 </DOCNO>
Absorption by Nonextremal D3-branes


  We calculate the absorption probabilities for a class of massless fields
whose linear perturbations leave the near-extremal D3-brane background metric
unperturbed. It has previously been found that, for extremal D3-branes, these
fields share the same absorption probability as that of the dilaton-axion. We
find that these absorption probabilities diverge from each other as we move
away from extremality. The form of the corresponding effective Schrodinger
potentials leads us to conjecture that the absorption of various fields by
nonextremal D3-branes depends on the polarization of angular momentum.

</DOC>
<DOC>
<DOCNO> 13021 </DOCNO>
Nonlinear fluctuation phenomena in the transport properties of


  There exists a wide temperature region $({\rm Gi}T<T-T_c<T\sqrt{{\rm Gi}})$,
where the influence of fluctuations on the thermodynamic properties of
superconductors can be taken into account in the linear (Gaussian)
approximation, while their influence on the kinetic properties is strongly
nonlinear. Maki-Thompson contribution to conductivity saturates in this region.
However, Aslamazov-Larkin contribution becomes even more singular. Such an
enhancement is connected with the fact that nonlinear effects yield an increase
in the lifetime of fluctuating pairs. Pairbreaking and energy relaxation
processes can diminish the nonlinear effects.

</DOC>
<DOC>
<DOCNO> 8704 </DOCNO>
Charge-orbital ordering and phase-separation in the two-orbital model


  The main properties of realistic models for manganites are studied using
analytic mean-field approximations and computational numerical methods,
focusing on the two-orbital model with electrons interacting through
Jahn-Teller (JT) phonons and/or Coulombic repulsions. Analyzing the model
including both interactions by the combination of the mean-field approximation
and the exact diagonalization method, it is argued that the spin-charge-orbital
structure in the insulating phase of the purely JT-phononic model is not
qualitatively changed by the inclusion of the Coulomb interactions. As an
important application of the present mean-field approximation, the CE-type AFM
state, the charge-stacked structure along the z-axis, and the
(3x^2-r^2)/(3y^2-r^2)-type orbital ordering are successfully reproduced based
on the JT-phononic model for the half-doped manganite. Topological arguments
and the relevance of the Heisenberg exchange among localized t_{\rm 2g} spins
explains why the nearest-neighbor Coulomb interaction does not destroy the
charge stacking structure. It is also verified that the phase-separation
tendency is observed both in purely JT-phononic and purely Coulombic models in
the vicinity of the hole undoped region, as long as realistic hopping matrices
are used. This highlights the qualitative similarities of both approaches, and
the relevance of mixed-phase tendencies in the context of manganites. In
addition, the rich and complex phase diagram of the two-orbital Coulombic model
in one dimension is presented. Our results provide robust evidence that
Coulombic and JT-phononic approaches to manganites are not qualitatively
different ways to carry out theoretical calculations, but they share a variety
of common features.

</DOC>
<DOC>
<DOCNO> 102604 </DOCNO>
A convexity theorem for torus actions on contact manifolds


  We show that the cone associated with a moment map for an action of a torus
on a contact compact connected manifold is a convex polyhedral cone and that
the moment map has connected fibers provided the dimension of the torus is
bigger than 2 and that no orbit is tangent to the contact distribution. This
may be considered as a version of the Atiyah - Guillemin - Sternberg convexity
theorem for torus actions on symplectic cones and as a direct generalization of
the convexity theorem of Banyaga and Molino for completely integrable torus
actions on contact manifolds.

</DOC>
<DOC>
<DOCNO> 84977 </DOCNO>
Mechanical quality factor of a sapphire fiber at cryogenic temperatures


  A mechanical quality factor of $1.1 \times 10^{7}$ was obtained for the 199
Hz bending vibrational mode in a monocrystalline sapphire fiber at 6 K.
Consequently, we confirm that pendulum thermal noise of cryogenic mirrors used
for gravitational wave detectors can be reduced by the sapphire fiber
suspension.

</DOC>
<DOC>
<DOCNO> 122378 </DOCNO>
Molecular hydrogen and the nature of damped Lyman-alpha systems


  We report results from our mini-survey for molecular hydrogen in eight high
redshift damped Lyman-alpha (DLA) systems using the ESO Ultra-violet and
Visible Spectrograph on the VLT. In addition, we investigate two systems using
ESO public data. We include in the sample the only system where H2 was
previously detected and studied at high-spectral resolution. Altogether our
sample consists of eleven absorbers with 1.85<z_abs<3.4. We confirm the
presence of H2 in the z_abs = 2.3377, metal-poor ([Si/H] = -1.20) system toward
PKS 1232+082. The derived molecular fraction, f = 2N(H2)/(2N(H2)+N(HI)) = 4
10-4, is two orders of magnitude less than what has been claimed previously
from low-resolution data. The physical conditions within the cloud can be
constrained directly from observation. The kinetic temperature and particle
density are in the ranges, respectively, 100<T<300 K and 30<nH<50 cm-3. In
addition, UV pumping is of the same order of magnitude than in our Galaxy. The
upper limits on the molecular fraction derived in nine of the systems are in
the range 1.2 10-7 - 1.6 10-5. The molecular abundance in a few DLA systems
(and in particular in the two systems where H2 is detected) is consistent with
what is seen in the Magellanic clouds. But most of the DLA measurements are
well below these values. This is probably partly due to small amounts of dust
and/or high UV flux. We argue however that the lack of molecules is a direct
consequence of high kinetic temperature (T>3000 K) implying a low formation
rate of H2 onto dust grains. Therefore, most of the DLA systems arise in warm
and diffuse neutral gas. (Abridged)

</DOC>
<DOC>
<DOCNO> 40426 </DOCNO>
Measurement of dijet cross sections for events with a leading neutron in


  Differential cross sections for dijet photoproduction in association with a
leading neutron using the reaction e^+ + p --> e^+ + n + jet + jet + X_r have
been measured with the ZEUS detector at HERA using an integrated luminosity of
6.4 pb^{-1}. The fraction of dijet events with a leading neutron in the final
state was studied as a function of the jet kinematic variables. The cross
sections were measured for jet transverse energies E^{jet}_T > 6 GeV, neutron
energy E_n > 400 GeV, and neutron production angle theta_n < 0.8 mrad. The data
are broadly consistent with factorization of the lepton and hadron vertices and
with a simple one-pion-exchange model.

</DOC>
<DOC>
<DOCNO> 8829 </DOCNO>
Low field negative magnetoresistance in double layer structures


  The weak localization correction to the conductivity in coupled double layer
structures is studied both experimentally and theoretically. Statistics of
closed paths has been obtained from the analysis of magnetic field and
temperature dependencies of negative magnetoresistance for magnetic field
perpendicular and parallel to the structure plane. The comparison of
experimental data with results of computer simulation of carrier motion over
two 2D layers with scattering shows that inter-layers transitions play decisive
role in the weak localization.

</DOC>
<DOC>
<DOCNO> 170785 </DOCNO>
Continuously induced coherence without induced emission


  The coherence properties of two downconversion processes continuously coupled
via idler beams are analyzed. We find that the amount of which-way information
about a signal photon carried by idler beams periodically attains its maximum
and minimum in the course of evolution. In correspondence with the famous
experiments by Mandel's group on the induced coherence without induced emission
the coherence of signal beams is governed by that information. The ideal
which-way measurement is constructed.

</DOC>
<DOC>
<DOCNO> 13289 </DOCNO>
Stochastic description for open quantum systems


  A linear open quantum system consisting of a harmonic oscillator linearly
coupled to an infinite set of independent harmonic oscillators is considered;
these oscillators have a general spectral density function and are initially in
a Gaussian state. Using the influence functional formalism a formal Langevin
equation can be introduced to describe the system's fully quantum properties
even beyond the semiclassical regime. It is shown that the reduced Wigner
function for the system is exactly the formal distribution function resulting
from averaging both over the initial conditions and the stochastic source of
the formal Langevin equation. The master equation for the reduced density
matrix is then obtained in the same way a Fokker-Planck equation can always be
derived from a Langevin equation characterizing a stochastic process. We also
show that a subclass of quantum correlation functions for the system can be
deduced within the stochastic description provided by the Langevin equation. It
is emphasized that when the system is not Markovian more information can be
extracted from the Langevin equation than from the master equation.

</DOC>
<DOC>
<DOCNO> 70195 </DOCNO>
Comment on Equal Velocity Assumption for Neutrino Oscillations


  The so-called equal velocity prescription for neutrino oscillations is
forbidden kinematically.

</DOC>
<DOC>
<DOCNO> 70895 </DOCNO>
Collective neutrino-pair emission due to Cooper pairing of protons in


  The neutrino emission due to formation and breaking of Cooper pairs of
protons in superconducting cores of neutron stars is considered with taking
into account the electromagnetic coupling of protons to ambient electrons. It
is shown that collective response of electrons to the proton quantum transition
contributes coherently to the complete interaction with a neutrino field and
enhances the neutrino-pair production. Our calculation shows that the
contribution of the vector weak current to the $\nu \bar{\nu}$ emissivity of
protons is much larger than that calculated by different authors without taking
into account the plasma effects. Partial contribution of the pairing protons to
the total neutrino radiation from the neutron star core is very sensitive to
the critical temperatures for the proton and neutron pairing. We show domains
of these parameters where the neutrino radiation, caused by a singlet-state
pairing of protons is dominating.

</DOC>
<DOC>
<DOCNO> 122215 </DOCNO>
VLBI imaging of the gravitational lenses B1422+231 and MGJ0414+0534


  We present wide-field images of the quadruple gravitational lenses B1422+231
and MGJ0414+0534 obtained from global Very Long Baseline Interferometry (VLBI)
observations at 8.4 GHz on 23 November 1997. We present also a lens model for
MGJ0414+0534, which reproduces the core positions and flux densities of the
VLBI images, combining a singular isothermal ellipsoid with external shear, and
a singular isothermal sphere to represent, respectively, the main lens galaxy
and its neighbor, a faint galaxy near one of the images.

</DOC>
<DOC>
<DOCNO> 7878 </DOCNO>
Transfer across Random versus Deterministic Fractal Interfaces


  A numerical study of the transfer across random fractal surfaces shows that
their responses are very close to the response of deterministic model
geometries with the same fractal dimension. The simulations of several
interfaces with prefractal geometries show that, within very good
approximation, the flux depends only on a few characteristic features of the
interface geometry: the lower and higher cut-offs and the fractal dimension.
Although the active zones are different for different geometries, the electrode
reponses are very nearly the same. In that sense, the fractal dimension is the
essential "universal" exponent which determines the net transfer.

</DOC>
<DOC>
<DOCNO> 117918 </DOCNO>
Transport Phenomena and Light Element Abundances in the Sun and Solar


  The observations of light elements in the Sun and Solar type stars give
special clues for understanding the hydrodynamical processes at work in stellar
interiors. In the Sun 7Li is depleted by 140 while 3He has not increased by
more than 10% in 3 Gyrs. Meanwhile the inversion of helioseismic modes lead to
a precision on the sound velocity of about .1%. The mixing processes below the
solar convection zone are constrained by these observations. Lithium is
depleted in most Pop I solar type stars. In halo stars however, the lithium
abundance seems constant in the "spite plateau" with no observed dispersion,
which is difficult to reconcile with the theory of diffusion processes. In the
present paper, the various relevant observations will be discussed. It will be
shown that the mu-gradients induced by element settling may help solving the
"lithium paradox".

</DOC>
<DOC>
<DOCNO> 119130 </DOCNO>
High magnetic field pulsars and magnetars: a unified picture


  We propose a unified picture of high magnetic field radio pulsars and
magnetars by arguing that they are all rotating high-field neutron stars, but
have different orientations of their magnetic axes with respective to their
rotation axes. In strong magnetic fields where photon splitting suppresses pair
creation near the surface, the high-field pulsars can have active inner
accelerators while the anomalous X-ray pulsars cannot. This can account for the
very different observed emission characteristics of the anomalous X-ray pulsar
1E 2259+586 and the high field radio pulsar PSR J1814-1744. A predicted
consequence of this picture is that radio pulsars having surface magnetic field
greater than about $2\times 10^{14}$ G should not exist.

</DOC>
<DOC>
<DOCNO> 118703 </DOCNO>
Clustering statistics on a light-cone in the cosmological redshift space


  We summarize a series of our recent work concerning the cosmological
redshift-space distortion and light-cone effects. After briefly describing the
theoretical formalism, we show how those effects are sensitive to the
cosmological parameters. Then we apply this formalism to predict the two-point
correlation functions and power spectra for the X-ray clusters, galaxies and
quasars in future surveys, and discuss their cosmological implications.

</DOC>
<DOC>
<DOCNO> 69887 </DOCNO>
Chiral fermions, orbifolds, scalars and fat branes


  We note that orbifold boundary conditions that produce chiral fermion zero
modes in compactified higher dimensional theories may distort scalar field
vacuum expectation values, giving rise to nontrivial dependence on the extra
dimensions. We illustrate this in a simple five dimensional model which has
chiral fermion zero-modes stuck to fat branes. The model could provide a simple
and explicit realization of the separation of quarks and leptons in the fifth
dimension. We discuss the KK expansion in some detail. We find that there are
in general non-zero-mode states stuck to the brane, like the chiral zero modes.
We see explicitly the transition from states dominated by the internal
structure of the fat brane to those dominated by the compactification.

</DOC>
<DOC>
<DOCNO> 67639 </DOCNO>
Atmospheric Neutrino Flux: A Review of Calculations


  Interpretation and understanding of the evidence for neutrino oscillations
depends on knowledge of the atmospheric neutrino beam. In this talk I assess
how well various features are known. The goal is to determine to what extent
uncertainties in the neutrino beam may limit the conclusions about neutrino
properties and which features of the evidence for neutrino oscillations are
most robust.

</DOC>
<DOC>
<DOCNO> 70388 </DOCNO>
Effective Field Theory of the Pion-Nucleon-Interaction


  In the first part of the talk, I discussed the nature of the effective theory
that describes the properties of the pion-nucleon-interaction at low energies,
using the static model as a starting point. In the second part, I then pointed
out that the infrared singularities occurring in the pi-N scattering amplitude
are stronger and of a more complex structure than those encountered in pi-pi
scattering. A formulation of the effective theory that properly accounts for
these was described and the results obtained thereby were illustrated with a
few examples.

</DOC>
<DOC>
<DOCNO> 101573 </DOCNO>
The inverse problem of the Birkhoff-Gustavson normalization and ANFER,


  In the series of papers [1-4], the inverse problem of the Birkhoff-Gustavson
normalization was posed and studied. To solve the inverse problem, the
symbolic-computing program named ANFER (Algorithm of Normal Form Expansion and
Restoration) is written up, with which a new aspect of the Bertrand and Darboux
integrability condition is found \cite{Uwano2000}. In this paper, the procedure
in ANFER is presented in mathematical terminology, which is organized on the
basis of the composition of canonical transformations.

</DOC>
<DOC>
<DOCNO> 69530 </DOCNO>
A Theoretical Prediction of the Bs-Meson Lifetime Difference


  We present the results of a quenched lattice calculation of the operator
matrix elements relevant for predicting the Bs width difference. Our main
result is (\Delta\Gamma_Bs/\Gamma_Bs)= (4.7 +/- 1.5 +/- 1.6) 10^(-2), obtained
from the ratio of matrix elements, R(m_b)=<\bar B_s^0|Q_S|B_s^0>/<\bar
B_s^0|Q_L|B_s^0>=-0.93(3)^(+0.00)_(-0.01). R(m_b) was evaluated from the two
relevant B-parameters, B_S^{MSbar}(m_b)=0.86(2)^(+0.02)_(-0.03) and
B_Bs^{MSbar}(m_b) = 0.91(3)^(+0.00)_(-0.06), which we computed in our
simulation.

</DOC>
<DOC>
<DOCNO> 9416 </DOCNO>
First-principles study of ferroelectric and antiferrodistortive


  We carry out first-principles density-functional calculations of the
antiferrodistortive (AFD) and ferroelectric (FE) soft-mode instabilities in
tetragonal SrTiO3, with the structural degrees of freedom treated in a
classical, zero-temperature framework. In particular, we use frozen-phonon
calculations to make a careful study of the anisotropy of the AFD and FE mode
frequencies in the tetragonal ground state, in which an R-point AFD soft phonon
has condensed. Because of the anharmonic couplings, the presence of this AFD
distortion substantially affects both the AFD and FE mode frequencies. The AFD
mode is found to be softer for rotations around a perpendicular axis (Eg mode)
than for rotations about the tetragonal axis (A1g mode), in agreement with
experimental results. The FE mode, on the other hand, is found to be softer
when polarized perpendicular to the tetragonal axis (Eu mode) than parallel to
it (A2u mode). The sign of this frequency splitting is consistent with the
experimentally reported anisotropy of the dielectric susceptibility and other
evidence. Finally, we present a discussion of the influence of various types of
structural distortions on the FE instability and its anisotropy.

</DOC>
<DOC>
<DOCNO> 116706 </DOCNO>
Stable oscillating nonlinear beams in


  We demonstrate experimentally that in a centrosymmetric paraelectric
non-stationary boundary conditions can dynamically halt the intrinsic
instability of quasi-steady-state photorefractive self-trapping, driving beam
evolution into a stable oscillating two-soliton-state configuration.

</DOC>
<DOC>
<DOCNO> 84172 </DOCNO>
Hyper-K{\"a}hler Hierarchies and their twistor theory


  A twistor construction of the hierarchy associated with the hyper-K\"ahler
equations on a metric (the anti-self-dual Einstein vacuum equations, ASDVE, in
four dimensions) is given. The recursion operator R is constructed and used to
build an infinite-dimensional symmetry algebra and in particular higher flows
for the hyper-K\"ahler equations. It is shown that R acts on the twistor data
by multiplication with a rational function. The structures are illustrated by
the example of the Sparling-Tod (Eguchi-Hansen) solution. An extended
space-time ${\cal N}$ is constructed whose extra dimensions correspond to
higher flows of the hierarchy. It is shown that ${\cal N}$ is a moduli space of
rational curves with normal bundle ${\cal O}(n)\oplus{\cal O}(n)$ in twistor
space and is canonically equipped with a Lax distribution for ASDVE
hierarchies. The space ${\cal N}$ is shown to be foliated by four dimensional
hyper-K{\"a}hler slices. The Lagrangian, Hamiltonian and bi-Hamiltonian
formulations of the ASDVE in the form of the heavenly equations are given. The
symplectic form on the moduli space of solutions to heavenly equations is
derived, and is shown to be compatible with the recursion operator.

</DOC>
<DOC>
<DOCNO> 102900 </DOCNO>
The Hodge Numbers of the Moduli Spaces of Vector Bundles over a Riemann


  Inductive formulas for the Betti numbers of the moduli spaces of stable
holomorphic vector bundles of coprime rank and degree over a fixed Riemann
surface of genus at least two were obtained by Harder, Narasimhan, Desale and
Ramanan using number theoretic methods and the Weil conjectures and were
rederived by Atiyah and Bott using gauge theory. In this note we observe that
there are similar inductive formulas for determining the Hodge numbers of these
moduli spaces.

</DOC>
<DOC>
<DOCNO> 9721 </DOCNO>
Combined Paramagnetic and Diamagnetic Response of YBCO


  It has been predicted that the zero frequency density of states of YBCO in
the superconducting phase can display interesting anisotropy effects when a
magnetic field is applied parallel to the copper-oxide planes, due to the
diamagnetic response of the quasi-particles. In this paper we incorporate
paramagnetism into the theory and show that it lessens the anisotropy and can
even eliminate it altogether. At the same time paramagnetism also changes the
scaling with the square root of the magnetic field first deduced by Volovik
leading to an experimentally testable prediction. We also map out the analytic
structure of the zero frequency density of states as a function of the
diamagnetic and paramagnetic energies. At certain critical magnetic field
values we predict kinks as we vary the magnetic field. However these probably
lie beyond currently accessible field strengths.

</DOC>
<DOC>
<DOCNO> 13588 </DOCNO>
Reply on Comment on ``Extraction of work from a single thermal bath in


  In our recent letter [1] we discussed that thermodynamics is violated in
quantum Brownian motion beyond the weak coupling limit. In his comment, Tasaki
[2] derives an inequality for the relative entropy and claims, without making
any dynamical assumption, that the Clausius inequality is valid, thus
contradicting our statements [1]. Here we point out that the claim is unfunded,
since the author did not properly identify the concept of heat. Tasaki also
applies the inequality to Thomson's formulation of the second law. This
application is invalid as well, since the author did not correctly identify the
concept of work. Therefore, Tasaki's inequality is perfectly compatible with
our findings.

</DOC>
<DOC>
<DOCNO> 170690 </DOCNO>
On the Qualitative Theory of Non-Gamov Decay States


  Complex potential transformations which add imaginary parts to chosen energy
levels are given and qualitatively explained. Unexpected shape similarity of
potential perturbations for real and imaginary E-shifts of bound states are
exhibited. The imaginary E-shifts in the continuous spectrum lead to a
surprising quasi-periodic field raking up initial propagating waves into
localized states. Complex periodic potentials without lacunas (!) are
constructed. The fission of quasi-bound states when neighbour complex
eigenvalues approach one another is demonstrated. E-shift algorithms represent
wide classes of exactly solvable quantum models for non-self-adjoint operators.

</DOC>
<DOC>
<DOCNO> 67881 </DOCNO>
Constraining the Higgs boson mass through the combination of direct


  We show that the likelihood ratio of Higgs search experiments is a form to
report the experimental results suitable to be combined with the information
from precision measurements to obtain a joint constraint on the Higgs mass. We
update our previous combined analysis using the new results on direct searches
and recent precision measurements, including also the Z0 leptonic partial width
result. The method is also improved to take into account small non linearity
effects in the theoretical formulae. We find an expected value for the Higgs
mass around 160-170 GeV with an expectation uncertainty, quantified by the
standard deviation of the distribution, of about 50-60 GeV. The 95% probability
upper limit comes out to be around 260-290 GeV.

</DOC>
<DOC>
<DOCNO> 85652 </DOCNO>
Quadratic s-Form Field Actions with Semi-bounded Energy


  We give in this paper a partial classification of the consistent quadratic
gauge actions that can be written in terms of s-form fields. This provides a
starting point to study the uniqueness of the Yang-Mills action as a
deformation of Maxwell-like theories. We also show that it is impossible to
write kinetic 1-form terms that can be consistently added to other 1-form
actions such as tetrad gravity in four space-time dimensions even in the
presence of a Minkowskian metric background.

</DOC>
<DOC>
<DOCNO> 83505 </DOCNO>
Towards Robust Quantum Computation


  Quantum computation is a subject of much theoretical promise, but has not
been realized in large scale, despite the discovery of fault-tolerant
procedures to overcome decoherence. Part of the reason is that the
theoretically modest requirements still present daunting experimental
challenges. The goal of this Dissertation is to reduce various resources
required for robust quantum computation, focusing on quantum error correcting
codes and solution NMR quantum computation. A variety of techniques have been
developed, including high rate quantum codes for amplitude damping, relaxed
criteria for quantum error correction, systematic construction of
fault-tolerant gates, recipes for quantum process tomography, techniques in
bulk thermal state computation, and efficient decoupling techniques to
implement selective coupled logic gates. A detailed experimental study of a
quantum error correcting code in NMR is also presented. The Dissertation
clarifies and extends results previously reported in quant-ph/9610043,
quant-ph/9704002, quant-ph/9811068, quant-ph/9904100, quant-ph/9906112,
quant-ph/0002039. Additionally, a procedure for quantum process tomography
using maximally entangled states, and a review on NMR quantum computation are
included.

</DOC>
<DOC>
<DOCNO> 101079 </DOCNO>
Relative Entropy: Free Energy Associated with Equilibrium Fluctuations


  Using a one-dimensional macromolecule in aqueous solution as an illustration,
we demonstrate that the relative entropy from information theory, $\sum_k
p_k\ln(p_k/p_k^*)$, has a natural role in the energetics of equilibrium and
nonequilibrium conformational fluctuations of the single molecule. It is
identified as the free energy difference associated with a fluctuating density
in equilibrium, and is associated with the distribution deviate from the
equilibrium in nonequilibrium relaxation. This result can be generalized to any
other isothermal macromolecular systems using the mathematical theories of
large deviations and Markov processes, and at the same time provides the
well-known mathematical results with an interesting physical interpretations.

</DOC>
<DOC>
<DOCNO> 120488 </DOCNO>
Evidence for Evolving Spheroidals in the Hubble Deep Fields North and


  We investigate the dispersion in the internal colours of faint spheroidals in
the HDFs North and South. We find that a remarkably large fraction ~30% of the
morphologically classified spheroidals with I<24 mag show strong variations in
internal colour, which we take as evidence for recent episodes of
star-formation. In most cases these colour variations manifest themselves via
the presence of blue cores, an effect of opposite sign to that expected from
metallicity gradients. Examining similarly-selected ellipticals in five rich
clusters with 0.37<z<0.83 we find a significant lower dispersion in their
internal colours. This suggests that the colour inhomogeneities have a strong
environmental dependence being weakest in dense environments where spheroidal
formation was presumably accelerated at early times. We use the trends defined
by the cluster sample to define an empirical model based on a high-redshift of
formation and estimate that at z~1 about half the field spheroidals must be
undergoing recent episodes of star-formation. Using spectral synthesis models,
we construct the time dependence of the density of star-formation. Although the
samples are currently small, we find evidence for an increase in $\rho_{SFR}$
between z=0 to z=1. We discuss the implications of this rise in the context of
that observed in the similar rise in the abundance of galaxies with irregular
morphology. Regardless of whether there is a connection our results provide
strong evidence for the continued formation of field spheroidals over 0<z<1.

</DOC>
<DOC>
<DOCNO> 100663 </DOCNO>
Connections between Linear Systems and Convolutional Codes


  The article reviews different definitions for a convolutional code which can
be found in the literature. The algebraic differences between the definitions
are worked out in detail. It is shown that bi-infinite support systems are dual
to finite-support systems under Pontryagin duality. In this duality the dual of
a controllable system is observable and vice versa. Uncontrollability can occur
only if there are bi-infinite support trajectories in the behavior, so finite
and half-infinite-support systems must be controllable. Unobservability can
occur only if there are finite support trajectories in the behavior, so
bi-infinite and half-infinite-support systems must be observable. It is shown
that the different definitions for convolutional codes are equivalent if one
restricts attention to controllable and observable codes.

</DOC>
<DOC>
<DOCNO> 85066 </DOCNO>
Instability of a membrane intersecting a black hole


  The stability of a Nambu-Goto membrane at the equatorial plane of the
Reissner-Nordstr{\o}m-de Sitter spacetime is studied. The covariant
perturbation formalism is applied to study the behavior of the perturbation of
the membrane. The perturbation equation is solved numerically. It is shown that
a membrane intersecting a charged black hole, including extremely charged one,
is unstable and that the positive cosmological constant strengthens the
instability.

</DOC>
<DOC>
<DOCNO> 121582 </DOCNO>
The HI halo of NGC 2403


  Deep VLA HI observations of the nearby spiral galaxy NGC 2403 reveal the
presence of an extended HI halo that shows slower rotation and a general inflow
(about 15-25 km\s) towards the center of the galaxy.

</DOC>
<DOC>
<DOCNO> 101190 </DOCNO>
Combinatorial formulas for products of Thom classes


  Let G be a torus of dimension n > 1 and M a compact Hamiltonian G-manifold
with $M^G$ finite. A circle, $S^1$, in G is generic if $M^G = M^{S^1}$. For
such a circle the moment map associated with its action on M is a perfect Morse
function. Let $\{ W_p^+ ; p \in M^G\}$ be the Morse-Whitney stratification of M
associated with this function, and let $\tau_p^+$ be the equivariant Thom class
dual to $W_p^+$. These classes form a basis of $H_G^*(M)$ as a module over
$\SS(\fg^*)$ and, in particular, $$\tau_p^+ \tau_q^+ = \sum c_{pq}^r \tau_r^+$$
with $c_{pq}^r \in \SS(\fg^*)$. For manifolds of GKM type we obtain a
combinatorial description of these $\tau_p^+$'s and, from this description, a
combinatorial formula for $c_{pq}^r$.

</DOC>
<DOC>
<DOCNO> 102691 </DOCNO>
A rigorous real time Feynman Path Integral and Propagator


  We will derive a rigorous real time propagator for the Non-relativistic
Quantum Mechanic $L^2$ transition probability amplitude and for the
Non-relativistic wave function. The propagator will be explicitly given in
terms of the time evolution operator. The derivation will be for all
self-adjoint nonvector potential Hamiltonians. For systems with potential that
carries at most a finite number of singularity and discontinuities, we will
show that our propagator can be written in the form of a rigorous real time,
time sliced Feynman path integral via improper Riemann integrals. We will also
derive the Feynman path integral in Nonstandard Analysis Formulation. Finally,
we will compute the propagator for the harmonic oscillator using the
Nonstandard Analysis Feynman path integral formuluation; we will compute the
propagator without using any knowledge of classical properties of the harmonic
oscillator.

</DOC>
<DOC>
<DOCNO> 70082 </DOCNO>
Renormalons and multiloop estimates in scalar correlators, Higgs decay


  The single renormalon-chain contribution to the correlator of scalar currents
in QCD is calculated in the $\bar{MS}$-scheme in the limit of a large $N_f$. We
find that in the factorial growth of the coefficients due to renormalons takes
over almost immediatelly in the euclidean region. The essential differences
between the large-order growth of coefficients in the scalar case, and in the
vector case are analysed. In the timelike region a stabilization of the
perturbative series for the imaginary part, with $n$-loop behaviour
$S_n/[\log(s/\Lambda^2)]^{n-1}$, where $S_n$ is essential constant for
$n\le{6}$, is observed. Only for $n\ge{7}$ does one discern the factorial
growth and alternations of sign. Out all-order results are used to scrutinize
the performance of multiloop estimates, within the ``naive nonabelianization''
procedure, and the effective charges approach. The asymtotic behaviour of
perturbative coefficients, in both large $N_f$ and large $N_c$ limits, is
analysed. A contour-improved resummation technique in the time-like region is
developed. Some subtleties of scheme-dependence are illustrated using results
in the $\bar{MS}$ and $V$-schemes. The all-order series under investigation are
summed up with the help of the Borel resummation method. The results obtained
are relevant to the analysis of the theoretical uncertainties in the 4-loop
extractions of the running and invariant $s$-quark masses from QCD sum rules,
and in calculations of the Higgs boson decay width into a quark-antiquark pair.

</DOC>
<DOC>
<DOCNO> 70126 </DOCNO>
Dimension-eight Operators in the Weak OPE


  We expose a potential flaw in standard treatments of weak decay amplitudes,
including that of epsilon'/epsilon. We show that (contrary to conventional
wisdom) dimension-eight operators do contribute to weak amplitudes, at order
G_F alpha_s and without 1/M_W^2 suppression. We demonstrate the existence of
these operators with a simple weak hamiltonian and proceed to discuss their
contribution in a general context. We estimate the effect of dimension-eight
operators to be at the 100% level in a sum rule determination of the operator
O_7 for mu = 1.5 GeV, suggesting presently available values of mu are too low
to justify neglect of these effects.

</DOC>
<DOC>
<DOCNO> 101643 </DOCNO>
Field theory and the Cohomology of Some Galois Groups


  We prove that two arithmetically significant extensions of a field F coincide
if and only if the Witt ring WF is a group ring Z/n[G]. Furthermore, working
modulo squares with Galois groups which are 2-groups, we establish a theorem
analogous to Hilbert's Theorem 90 and show that an identity linking the
cohomological dimension of the Galois group of the quadratic closure of F, the
length of a filtration on a certain module over a Galois group, and the
dimension over Z/2 of the square class group of the field holds for a number of
interesting families of fields. Finally we discuss the cohomology of a
particular Galois group in a topological context.

</DOC>
<DOC>
<DOCNO> 102341 </DOCNO>
Formation of singularities for equivariant 2+1 dimensional wave maps


  In this paper we report on numerical studies of the Cauchy problem for
equivariant wave maps from 2+1 dimensional Minkowski spacetime into the
two-sphere. Our results provide strong evidence for the conjecture that large
energy initial data develop singularities in finite time and that singularity
formation has the universal form of adiabatic shrinking of the degree-one
harmonic map from $\mathbb{R}^2$ into $S^2$.

</DOC>
<DOC>
<DOCNO> 150756 </DOCNO>
Local Quantum Observables in the Anti-deSitter - Conformal QFT


  Quantum field theory on d+1-dimensional anti-deSitter space-time admits a
re-interpretation as a quantum field theory with conformal symmetry on
d-dimensional Minkowski space-time. This conjecture originally emerged from
string theory considerations. Here, it is proven in a general framework by an
explicit identification between the local observables of the two corresponding
theories.

</DOC>
<DOC>
<DOCNO> 118088 </DOCNO>
QSO Absorption Line Constraints on Intragroup High-Velocity Clouds


  We show that the number statistics of moderate redshift MgII and Lyman limit
absorbers may rule out the hypothesis that high velocity clouds are infalling
intragroup material.

</DOC>
<DOC>
<DOCNO> 68620 </DOCNO>
Single top quark tW+X production at the LHC: a closer look


  We have reexamined the tW+X single top-quark production process which is
important at the LHC contrary to the Tevatron. The special attention was paid
to the treatment of the 2->2[Wt] process and the part of it's next-to-leading
correction: 2->3[Wtb] process. We show that 2->3[Wtb] process has to be
correctly taken into account with a proper subtraction of the top pair
contribution and that it has qualitatively different kinematical distributions
from the 2->2[Wt] process. We present the total cross section of the tW+X
production to be about 62 pb at QCD scale be taken as a top quark mass, suggest
the method of combining Wt and Wtb processes with gauge invariant subtraction
of the tt-bar part which allows to reproduce correct kinematical properties and
perform a proper event simulation of the tW+X process in the whole kinematical
region.

</DOC>
<DOC>
<DOCNO> 120106 </DOCNO>
The Reionization of the Universe and the Photoevaporation of


  The first sources of ionizing radiation to condense out of the dark and
neutral IGM sent ionization fronts sweeping outward through their surroundings,
overtaking other condensed objects and photoevaporating them. This feedback of
universal reionization on cosmic structure formation is demonstrated here by
gas dynamical simulations, including radiative transfer, for a cosmological
minihalo of dark matter and baryons exposed to an external source of ionizing
radiation, either starlight or quasar light, just after the passage of the
global ionization front created by the source.

</DOC>
<DOC>
<DOCNO> 70554 </DOCNO>
Light-Front QCD in Light-Cone Gauge


  The light-front (LF) quantization of QCD in light-cone (l.c.) gauge is
discussed. The Dirac method is employed to construct the LF Hamiltonian and
theory quantized canonically. The Dyson-Wick perturbation theory expansion
based on LF-time ordering is constructed. The framework incorporates in it
simultaneously the Lorentz gauge condition as an operator equation as well. The
propagator of the dynamical $\psi_+$ part of the free fermionic propagator is
shown to be causal while the gauge field propagator is found to be transverse.
The interaction Hamiltonian is re-expressed in the form closely resembling the
one in covariant theory, except for additional instantaneous interactions,
which can be treated systematically. Some explicit computations in QCD are
given.

</DOC>
<DOC>
<DOCNO> 8616 </DOCNO>
Remanent magnetization of high-temperature Josephson junction arrays


  In this work we study the remanent magnetization exhibited by tridimensional
disordered high-Tc Josephson junction arrays excited by an AC magnetic field.
The effect, as predicted by numerical simulations and previously verified for a
low-Tc array of Nb, occurs in a limited range of temperatures. We also show
that the magnetized state can be excited and detected by two alternative
experimental routines.

</DOC>
<DOC>
<DOCNO> 102361 </DOCNO>
Geometric Quantization on the Super-Disc


  In this article we discuss the geometric quantization on a certain type of
infinite dimensional super-disc. Such systems are quite natural when we analyze
coupled bosons and fermions. The large-N limit of a system like that
corresponds to a certain super-homogeneous space. First, we define an example
of a super-homogeneous manifold: a super-disc. We show that it has a natural
symplectic form, it can be used to introduce classical dynamics once a
Hamiltonian is chosen. Existence of moment maps provide a Poisson realization
of the underlying symmetry super-group. These are the natural operators to
quantize via methods of geometric quantization, and we show that this can be
done.

</DOC>
<DOC>
<DOCNO> 99608 </DOCNO>
Minimal Escape velocities


  We give a new derivation of the minimal velocity estimates for unitary
evolutions with some optimal bounds.

</DOC>
<DOC>
<DOCNO> 84693 </DOCNO>
Is Barbero's Hamiltonian formulation a Gauge Theory of Lorentzian


  This letter is a critique of Barbero's constrained Hamiltonian formulation of
General Relativity on which current work in Loop Quantum Gravity is based.
While we do not dispute the correctness of Barbero's formulation of general
relativity, we offer some criticisms of an aesthetic nature. We point out that
unlike Ashtekar's complex SU(2) connection, Barbero's real SO(3) connection
does not admit an interpretation as a space-time gauge field. We show that if
one tries to interpret Barbero's real SO(3) connection as a space-time gauge
field, the theory is not diffeomorphism invariant. We conclude that Barbero's
formulation is not a gauge theory of gravity in the sense that Ashtekar's
Hamiltonian formulation is. The advantages of Barbero's real connection
formulation have been bought at the price of giving up the description of
gravity as a gauge field.

</DOC>
<DOC>
<DOCNO> 121237 </DOCNO>
Discovery of a Luminous, Variable, Off-Center Source in the Nucleus of


  We present results from observations of the most famous starburst galaxy M82
with the High-Resolution Camera onboard the Chandra X-Ray Observatory. We found
nine sources in the central 1' x 1' region, but no source was detected at the
galactic center. Comparing the observations on 1999 October 28 and on 2000
January 20, we found four of the nine sources showed significant time
variability. In particular, CXOM82J095550.2+694047, which is 9" away from the
galactic center, showed extremely large time variability. We conclude that this
source is the origin of the hard X-ray time variability of M82 detected with
ASCA. Assuming a spectral shape obtained by the ASCA observation, its
luminosity in the 0.5 -- 10 keV band changed from 1.2E40 erg/s on 1999 October
28 to 8.7E40 erg/s on 2000 January 20.

</DOC>
<DOC>
<DOCNO> 11936 </DOCNO>
Conserved Dynamics and Interface Roughening in Spontaneous Imbibition :


  Imbibition phenomena have been widely used experimentally and theoretically
to study the kinetic roughening of interfaces. We critically discuss the
existing experiments and some associated theoretical approaches on the scaling
properties of the imbibition front, with particular attention to the
conservation law associated to the fluid, to problems arising from the actual
structure of the embedding medium, and to external influences such as
evaporation and gravity. Our main conclusion is that the scaling of moving
interfaces includes many crossover phenomena, with competition between the
average capillary pressure gradient and its fluctuations setting the maximal
lengthscale for roughening. We discuss the physics of both pinned and moving
interfaces and the ability of the existing models to account for their
properties.

</DOC>
<DOC>
<DOCNO> 178738 </DOCNO>
Time-Evolution of the Coherent and the Squeezed States of Many-Body


  Various works performed by the present authors in the 1990s are reviewed. The
topics discussed in this paper are mainly related to the time-evolution of the
coherent and the squeezed states of the systems obeying the su(2)- and the
su(1,1)-algebra. The formulations are based on the basic idea of the boson
mapping and the TDHF theory in canonical form. Under the time-dependent
variational procedure for trial states appropriately chosen, the time-evolution
of the systems under investigation is described. Further, it is shown that this
method enables us to obtain the classical counterparts of the original quantal
systems.

</DOC>
<DOC>
<DOCNO> 121757 </DOCNO>
Early Metal Enrichment of the Intergalactic Medium by Pregalactic


  We assess supernova (SN)-driven pregalactic outflows as a mechanism for
distributing the product of stellar nucleosynthesis over large cosmological
volumes prior to the reionization epoch. SN ejecta will escape the grasp of
halos with virial temperatures T_vir>10^{4.3} K (corresponding to masses M>10^8
h^{-1} M_sun at redshift z=9 when they collapse from 2-sigma fluctuations) if
rapid cooling can take place, and a significant fraction of their baryonic mass
is converted into stars over a dynamical timescale. We study the evolution of
SN-driven bubbles as they blow out from subgalactic halos and propagate into
the intergalactic medium (IGM), and show that to lift the halo gas out of the
potential well the energy injection must continue at least until blow-away
occurs. The collective explosive output of about ten thousands SNe per halo at
these early epochs could pollute vast regions of intergalactic space to a mean
metallicity <Z>=Omega_Z/Omega_b>0.003 (comparable to the levels observed in the
Lyman-alpha forest at z=3) without much perturbing the IGM hydrodynamically,
i.e. producing large variations of the baryons relative to the dark matter. The
volume filling factor of the ejecta is higher than 20% if the star formation
efficiency is of order 10%. When the filling factor of the ejecta becomes
significant, enriched material will typically be at a higher adiabat than
expected from photoionization.

</DOC>
<DOC>
<DOCNO> 39937 </DOCNO>
The ttbar Threshold and Machine Parameters at the NLC


  One of the problems in the design of a high energy e+e- linear collider is
the distribution of the luminosity as a function of real collision energy,
dL/dE, due to initial state radiation, beamstrahlung, and the energy spread of
the collider. These effects smear a sharp feature in the cross section of e+e-
-> hadrons such as the ttbar threshold into a flatter structure. This study
reviews the impact on dL/dE of these effects as a function of machine
parameters, explores some methods of measuring dL/dE with Bhabha scattering,
how the dL/dE flattens the ttbar cross section near threshold, and the effect
the dL/dE measurement has on extracting parameters of the top quark, such as
the mass and width, in a 2.5/fb scan of the ttbar threshold.

</DOC>
<DOC>
<DOCNO> 169952 </DOCNO>
Basic limitations for entanglement catalysis


  In this paper we summarize the necessary condition for incomparable states
which can be catalyzed under entanglement-assisted LQCC (ELQCC). When we apply
an extended condition for entanglement transformation to entanglement-assisted
local manipulation we obtain a fundamental limit for entanglement catalysts.
Some relative questions are also discussed.

</DOC>
<DOC>
<DOCNO> 40470 </DOCNO>
Novel Method of Measuring Electron Positron Colliding Beam Parameters


  Through the simultaneous measurement of the transverse size as a function of
longitudinal position, and the longitudinal distribution of luminosity, we are
able to measure the $\beta_y^\ast$ (vertical envelope function at the collision
point), vertical emittance, and bunch length of colliding beams at the Cornell
Electron-positron Storage Ring (CESR). This measurement is possible due to the
significant ``hourglass'' effect at CESR and the excellent tracking resolution
of the CLEO detector.

</DOC>
<DOC>
<DOCNO> 9148 </DOCNO>
Discontinuous transitions in double exchange materials


  It is shown that the double exchange Hamiltonian, with weak antiferromagnetic
interactions, has a rich variety of first order transitions between phases with
different electronic densities and/or magnetizations. For band fillings in the
range $0.3 \le x \le 0.5$, and at finite temperatures, a discontinuous
transition between phases with similar electronic densities but different
magnetizations takes place. This sharp transition, which is not suppressed by
electrostatic effects, and survives in the presence of an applied field, is
consistent with the phenomenology of the doped manganites near the transition
temperature.

</DOC>
<DOC>
<DOCNO> 13431 </DOCNO>
Localize energy in random media: A new phase state


  This Letter reports a new wave phenomenon. We show that wave energy can be
stored in random media. Associated with such energy storage is a global
collective behavior. The features depicted are so general that they may be
observed in many random systems.

</DOC>
<DOC>
<DOCNO> 9786 </DOCNO>
Highly anisotropic g-factor of two-dimensional hole systems


  Coupling the spin degree of freedom to the anisotropic orbital motion of
two-dimensional (2D) hole systems gives rise to a highly anisotropic Zeeman
splitting with respect to different orientations of an in-plane magnetic field
B relative to the crystal axes. This mechanism has no analogue in the bulk band
structure. We obtain good, qualitative agreement between theory and
experimental data, taken in GaAs 2D hole systems grown on (113) substrates,
showing the anisotropic depopulation of the upper spin subband as a function of
in-plane B.

</DOC>
<DOC>
<DOCNO> 123107 </DOCNO>
The ASCA Catalog of Potential X-Ray Counterparts of GeV Sources


  We present a catalog of 2-10 keV ASCA Gas Imaging Spectrometer images of
fields containing bright sources of GeV emission. The images cover $\sim 85%$
of the 95% confidence position contour for 28 of the 30 sources with $> 1$ GeV
fluxes above $4\times 10^{-8}$ ph ${\rm cm}^{-2} {\rm s}^{-1}$. We find an
excess of hard X-ray sources with $F_{2-10 keV} \ga 10^{-12}$ ergs ${\rm
cm}^{-2} {\rm s}^{-1}$ positionally coincident with unidentified sources of GeV
emission. We comment on radio-loud and radio-quiet pulsar candidates, as well
as several SNR and massive binaries as possible sources of the GeV emission. We
also find evidence for a class of variable $\gamma-$ray sources associated with
extended regions of hard X-ray emission, and propose that for these sources, a
significant percentage of the $\gamma-$ray emission is generated in synchrotron
nebulae surrounding fast, young pulsars.

</DOC>
<DOC>
<DOCNO> 13426 </DOCNO>
An entropy-driven noise-induced phase transition


  We introduce a class of exactly solvable models which exhibit an ordering
noise-induced phase transition driven by an entropic mechanism. In contrast
with previous studies, order does not appear in this case as a result of an
instability of the disordered phase produced by noise, but of a balance between
the relaxing deterministic dynamics and the randomizing (entropic) character of
the fluctuations. A finite-size scaling analysis of the phase transition
reveals that it belongs to the universality class of the equilibrium Ising
model. All these results are analyzed in the light of the nonequilibrium
probability distribution of the system, which can be derived analytically. The
relevance of our result as a possible scenario of the so-called Lower Critical
Solution Temperature (LCST) transitions is analysed.

</DOC>
<DOC>
<DOCNO> 118759 </DOCNO>
The Anisotropy of MHD Alfv\'{e}nic Turbulence


  We perform direct 3-dimensional numerical simulations for magnetohydrodynamic
(MHD) turbulence in a periodic box of size $2\pi$ threaded by strong uniform
magnetic fields. We use a pseudo-spectral code with hyperviscosity and
hyperdiffusivity to solve the incompressible MHD equations. We analyze the
structure of the eddies as a function of scale. A straightforward calculation
of anisotropy in wavevector space shows that the anisotropy is scale-{\it
independent}. We discuss why this is {\it not} the true scaling law and how the
curvature of large-scale magnetic fields affects the power spectrum and leads
to the wrong conclusion. When we correct for this effect, we find that the
anisotropy of eddies depends on their size: smaller eddies are more elongated
than larger ones along {\it local} magnetic field lines. The results are
consistent with the scaling law $\tilde{k}_{\parallel} \sim
\tilde{k}_{\perp}^{2/3}$ proposed by Goldreich and Sridhar (1995, 1997). Here
$\tilde{k}_{\|}$ (and $\tilde{k}_{\perp}$) are wavenumbers measured relative to
the local magnetic field direction. However, we see some systematic deviations
which may be a sign of limitations to the model, or our inability to fully
resolve the inertial range of turbulence in our simulations.

</DOC>
<DOC>
<DOCNO> 120786 </DOCNO>
Nuclear Aspects of Nucleosynthesis in Massive Stars


  Preliminary results of a new set of stellar evolution and nucleosynthesis
calculations for massive stars are presented. These results were obtained with
an extended reaction network up to Bi. The discussion focuses on the importance
of nuclear rates in pre- and post-explosive nucleosynthesis. The need for
further experiments to study specific reactions and nuclear properties (optical
alpha+nucleus potentials) is emphasized.

</DOC>
<DOC>
<DOCNO> 7980 </DOCNO>
Antilocalization in a 2D Electron Gas in a Random Magnetic Field


  We construct a supersymmetric field theory for the problem of a
two-dimensional electron gas in a random, static magnetic field. We find a new
term in the free energy, additional to those present in the conventional
unitary sigma-model, whose presence relies on the long-range nature of the
disorder correlations. Under a perturbative renormalization group analysis of
the free energy, the new term contributes to the scaling function at one-loop
order and leads to antilocalization.

</DOC>
<DOC>
<DOCNO> 7631 </DOCNO>
Effect of unitary impurities in non-STM-types of tunneling in high-T_c


  Based on an extended Hubbard model, we present calculations of both the local
(i.e., single-site) and spatially-averaged differential tunneling conductance
in d-wave superconductors containing nonmagnetic impurities in the unitary
limit. Our results show that a random distribution of unitary impurities of any
concentration can at most give rise to a finite zero-bias conductance (with no
peak there) in spatially-averaged non-STM type of tunneling, in spite of the
fact that local tunneling in the immediate vicinity of an isolated impurity
does show a conductance peak at zero bias, whereas to give rise to even a small
zero-bias conductance peak in the former type of tunneling the impurities must
form dimers, trimers, etc. along the [110] directions. In addition, we find
that the most-recently-observed novel pattern of the tunneling conductance
around a single impurity by Pan et al. [Nature (London) 403,746 (2000)] can be
explained in terms of a realistic model of the tunneling configuration which
gives rise to the experimental results reported there. The key feature in this
model is the blocking effect of the BiO and SrO layers which exist between the
tunneling tip and the CuO_2 layer being probed.

</DOC>
<DOC>
<DOCNO> 8352 </DOCNO>
Thermodynamically consistent mesoscopic fluid particle models for a van


  The GENERIC structure allows for a unified treatment of different discrete
models of hydrodynamics. We first propose a finite volume Lagrangian
discretization of the continuum equations of hydrodynamics through the Voronoi
tessellation. We then show that a slight modification of these discrete
equations has the GENERIC structure. The GENERIC structure ensures
thermodynamic consistency and allows for the introduction of correct thermal
noise. In this way, we obtain a consistent discrete model for Lagrangian
fluctuating hydrodynamics. For completeness, we also present the GENERIC
versions of the Smoothed Particle Dynamics model and of the Dissipative
Particle Dynamics model. The thermodynamic consistency endorsed by the GENERIC
framework allows for a coherent discussion of the gas-liquid phase coexistence
of a van der Waals fluid.

</DOC>
<DOC>
<DOCNO> 121188 </DOCNO>
Chandra study of an overdensity of X-ray sources around two distant


  We present results from a Chandra X-ray Observatory study of the field X-ray
source populations in 4 different observations: two high-redshift (z~0.5)
clusters of galaxies 3C295 and RXJ003033.2+261819; and two non-cluster fields
with similar exposure time. Surprisingly, the 0.5-2 keV source surface
densities (~900-1200 sources deg**-2 at a flux limit of 1.5x10**-15 erg
cm**-2s**-1) measured in an ~8'x8' area surrounding each cluster exceed by a
factor of ~2 the value expected on the basis of the ROSAT and Chandra
logN-logS, with a significance of ~2 sigma each, or ~3.5 sigma when the 2
fields are combined (i.e. a probability to be a statistical fluctuation of <1%
and <0.04%, respectively). The same analysis performed on the non-cluster
fields and on the outer chips of the cluster fields does NOT show evidence of
such an excess. In both cluster fields, the summed 0.5-10 keV spectrum of the
detected objects is well fitted by a power-law with Gamma~1.7 similar to AGNs
and shows no sign of intrinsic absorption. The few (~10 out of 35) optical
identifications available to date confirm that most of them are, as expected,
AGNs but the number of redshifts available is too small to allow conclusions on
their nature. We discuss possible interpretations of the overdensity in terms
of: a statistical variation of Cosmic Background sources; a concentration of
AGNs and/or powerful starburst galaxies associated with the clusters; and g
ravitational lensing of background QSO's by the galaxy clusters. All
explanations are however difficult to reconcile with the large number of excess
sources detected. Deeper X-ray observations and more redshifts measurements are
clearly required to settle the issue.

</DOC>
<DOC>
<DOCNO> 120917 </DOCNO>
The Intrinsic Absorber in QSO 2359-1241: Keck and HST Observations


  We present detailed analyses of the absorption spectrum seen in QSO 2359-1241
(NVSS J235953-124148). Keck HIRES data reveal absorption from twenty
transitions arising from: He I, Mg I, Mg II, Ca II, and Fe II. HST data show
broad absorption lines (BALs) from Al III 1857, C IV 1549, Si IV 1397, and N V
1240. Absorption from excited Fe II states constrains the temperature of the
absorber to 2000K < T < 10,000K and puts a lower limit of 10^5 cm^{-3} on the
electron number density. Saturation diagnostics show that the real column
densities of He I and Fe II can be determined, allowing to derive meaningful
constraints on the ionization equilibrium and abundances in the flow. The
ionization parameter is constrained by the iron, helium and magnesium data to
-3.0 < log(U) < -2.5 and the observed column densities can be reproduced
without assuming departure from solar abundances. From comparison of the He I
and Fe II absorption features we infer that the outflow seen in QSO 2359-1241
is not shielded by a hydrogen ionization front and therefore that the existence
of low-ionization species in the outflow (e.g., Mg II, Al III, Fe II) does not
necessitate the existence of such a front. We find that the velocity width of
the absorption systematically increases as a function of ionization and to a
lesser extent with abundance. Complementary analyses of the radio and
polarization properties of the object are discussed in a companion paper
(Brotherton et al. 2000).

</DOC>
<DOC>
<DOCNO> 72238 </DOCNO>
2000 CKM-Triangle Analysis A Critical Review with Updated Experimental


  Within the Standard Model, a review of the current determination of the sides
and angles of the CKM unitarity triangle is presented, using experimental
constraints from the measurements of |\epsilon_K|, |V_{ub}/V_{cb}|, \Delta m_d
and from the limit on \Delta m_s, available in September 2000. Results from the
experimental search for {B}^0_s-\bar{B}^0_s oscillations are introduced in the
present analysis using the likelihood. Special attention is devoted to the
determination of the theoretical uncertainties. The purpose of the analysis is
to infer regions where the parameters of interest lie with given probabilities.
The BaBar "95 %, C.L. scanning" method is also commented.

</DOC>
<DOC>
<DOCNO> 100841 </DOCNO>
Bicomplexes, Integrable Models, and Noncommutative Geometry


  We discuss a relation between bicomplexes and integrable models, and consider
corresponding noncommutative (Moyal) deformations. As an example, a
noncommutative version of a Toda field theory is presented.

</DOC>
<DOC>
<DOCNO> 83334 </DOCNO>
Interfacing Constraint-Based Grammars and Generation Algorithms


  Constraint-based grammars can, in principle, serve as the major linguistic
knowledge source for both parsing and generation. Surface generation starts
from input semantics representations that may vary across grammars. For many
declarative grammars, the concept of derivation implicitly built in is that of
parsing. They may thus not be interpretable by a generation algorithm. We show
that linguistically plausible semantic analyses can cause severe problems for
semantic-head-driven approaches for generation (SHDG). We use SeReal, a variant
of SHDG and the DISCO grammar of German as our source of examples. We propose a
new, general approach that explicitly accounts for the interface between the
grammar and the generation algorithm by adding a control-oriented layer to the
linguistic knowledge base that reorganizes the semantics in a way suitable for
generation.

</DOC>
<DOC>
<DOCNO> 85467 </DOCNO>
Asymptotic behaviour of cylindrical waves interacting with spinning


  We consider a family of cylindrical spacetimes endowed with angular momentum
that are solutions to the vacuum Einstein equations outside the symmetry axis.
This family was recently obtained by performing a complete gauge fixing adapted
to cylindrical symmetry. In the present work, we find boundary conditions that
ensure that the metric arising from this gauge fixing is well defined and that
the resulting reduced system has a consistent Hamiltonian dynamics. These
boundary conditions must be imposed both on the symmetry axis and in the region
far from the axis at spacelike infinity. Employing such conditions, we
determine the asymptotic behaviour of the metric close to and far from the
axis. In each of these regions, the approximate metric describes a conical
geometry with a time dislocation. In particular, around the symmetry axis the
effect of the singularity consists in inducing a constant deficit angle and a
timelike helical structure. Based on these results and on the fact that the
degrees of freedom in our family of metrics coincide with those of cylindrical
vacuum gravity, we argue that the analysed set of spacetimes represent
cylindrical gravitational waves surrounding a spinning cosmic string. For any
of these spacetimes, a prediction of our analysis is that the wave content
increases the deficit angle at spatial infinity with respect to that detected
around the axis.

</DOC>
<DOC>
<DOCNO> 71538 </DOCNO>
CP Violation


  Three possibilities for the origin of CP violation are discussed: (1) the
Standard Model in which all CP violation is due to one parameter in the CKM
matrix, (2) the superweak model in which all CP violation is due to new physics
and (3) the Standard Model plus new physics. A major goal of B physics is to
distinguish these possibilities. CP violation implies time reversal violation
(TRV) but direct evidence for TRV is difficult to obtain.

</DOC>
<DOC>
<DOCNO> 122525 </DOCNO>
Continuous Fields and Discrete Samples: Reconstruction through Delaunay


  Here we introduce the Delaunay Density Estimator Method. Its purpose is
rendering a fully volume-covering reconstruction of a density field from a set
of discrete data points sampling this field. Reconstructing density or
intensity fields from a set of irregularly sampled data is a recurring key
issue in operations on astronomical data sets, both in an observational context
as well as in the context of numerical simulations. Our technique is based upon
the stochastic geometric concept of the Delaunay tessellation generated by the
point set. We shortly describe the method, and illustrate its virtues by means
of an application to an N-body simulation of cosmic structure formation. The
presented technique is a fully adaptive method: automatically it probes high
density regions at maximum possible resolution, while low density regions are
recovered as moderately varying regions devoid of the often irritating
shot-noise effects. Of equal importance is its capability to sharply and
undilutedly recover anisotropic density features like filaments and walls. The
prominence of such features at a range of resolution levels within a
hierarchical clustering scenario as the example of the standard CDM scenario is
shown to be impressively recovered by our scheme.

</DOC>
<DOC>
<DOCNO> 13696 </DOCNO>
Dynamic dislocation drag near to a point of martensitic transformation


  The influence of coherent interface on dissipations of mechanical energy of
driven dislocations near to a point of martensite type phase transition is
considered. The expressions for dynamic braking of dislocations, owing to
losses of energy on excitation of deformations-type phase transition are
received.

</DOC>
<DOC>
<DOCNO> 71272 </DOCNO>
Hadronic centrality dependence in nuclear collisions


  The kaon number density in nucleus+nucleus and p+p reactions is investigated
for the first time as a function of the initial energy density $\epsilon$ and
is found to exhibit a discontinuity around $\epsilon$=1.3 GeV/fm$^3$. This
suggests a higher degree of chemical equilibrium for $\epsilon >$
  1.3 GeV/fm$^3$. It can also be interpreted as reflection of the same
discontinuity, appearing in the chemical freeze out temperature (T) as a
function of $\epsilon$. The $N^{\alpha \sim 1}$ dependence of (u,d,s) hadrons,
with N the number of participating nucleons, also indicates a high degree of
chemical equilibrium and T saturation, reached at $\epsilon >$1.3
GeV/fm$^3$.Assuming that the intermediate mass region (IMR) dimuon enhancement
seen by NA50 is due to open charm ($D \bar{D}$), the following observation can
be made: a) Charm is not equilibrated. b) $J/\Psi/D \bar{D}$ suppression
-unlike $J/\Psi/DY$- appears also in S+A collisions, above $\epsilon$ $\sim$1
GeV/fm$^3$. c) Both charm and strangeness show a discontinuity near the same
$\epsilon$. d) $J/\Psi$ could be formed mainly through $c \bar{c}$ coalescence.
e) The enhancement factors of hadrons with u,d,s,c quarks may be connected in a
simple way to the mass gain of these particles if they are produced out of a
quark gluon plasma (QGP). We discuss these results as possible evidence for the
QCD phase transition occuring near $\epsilon \sim $1.3 GeV/fm$^3$.

</DOC>
<DOC>
<DOCNO> 122293 </DOCNO>
Is There Still Room for Warm/Hot Gas? Simulating the X-ray Background


  At low redshifts, a census of the baryons in all known reservoirs falls a
factor of two to four below the total baryon density predicted from Big Bang
nucleosynthesis arguments and observed light element ratios. Recent
cosmological hydrodynamic simulations suggest that a significant fraction of
these missing baryons could be in the form of warm/hot gas in the filaments and
halos within which most field galaxies are embedded. With the release of source
count results from Chandra and recent detections of this gas in O VI quasar
absorption lines, it becomes interesting to examine the predictions and limits
placed on this component of the X-ray background (XRB). We have used new
hydrodynamical simulations to predict the total X-ray spectrum from the gas in
the 100 eV to 10 keV range. We find that, when uncertainties in the
normalization of the observed XRB and the value of Omega_b are taken into
account, our results are consistent with current observational limits placed on
the contribution of emission from gas to the XRB. In the 0.5-2 keV range, we
expect the contribution from this component to be 0.63 10^{-12} erg s^-1 cm^-2
deg^-2 or between 6% and 18% of the extragalactic surface brightness. The peak
fraction occurs in the 0.5-1 keV range where the predicted line emission
mirrors a spectral bump seen in the latest ASCA/ROSAT XRB data.

</DOC>
<DOC>
<DOCNO> 84384 </DOCNO>
Poincar\'e invariance in the ADM Hamiltonian approach to the general


  A previously found momentum-dependent regularization ambiguity in the third
post-Newtonian two point-mass Arnowitt-Deser-Misner Hamiltonian is shown to be
uniquely determined by requiring global Poincar\'e invariance. The phase-space
generators realizing the Poincar\'e algebra are explicitly constructed.

</DOC>
<DOC>
<DOCNO> 70536 </DOCNO>
Photon Structure Functions Beyind the SUSY Threshold


  We evolve virtual photon parton densities up to the SUSY threshold and higher
using coupled inhomogeneous DGLAP differential equations. Reliable input
parameterizations were available from the c-quark threshold. Limited
 $P^2$ ( target photon virtuality ) dependence is observed. The difference to
the photon structure function is shown to be significant with the introduction
of SUSY dependent splitting functions. A negligible difference is observed by
letting the gluino mass enter after the squark mass. An effort is made to
include the squark threshold effect in such a way that both the renormalization
group equations are satisfied and the perturbative calculation is reproduced.

</DOC>
<DOC>
<DOCNO> 178585 </DOCNO>
Effects of the Neutron Spin-Orbit Density on Nuclear Charge Density in


  The neutron spin-orbit density contributes to the nuclear charge density as a
relativistic effect. The contribution is enhanced by the effective mass
stemming from the Lorentz-scalar potential in relativistic models. This
enhancement explains well the difference between the cross sections of elastic
electron scattering off $^{40}$Ca and $^{48}$Ca which was not reproduced in
non-relativistic models. The spin-orbit density will be examined in more detail
in electron scattering off unstable nuclei which would be available in the
future.

</DOC>
<DOC>
<DOCNO> 71965 </DOCNO>
Integral characteristics of bremsstrahlung and pair photoproduction in a


  The bremsstrahlung of an electron and $e^{-}e^{+}$-pair creation by a photon
in a medium is considered in high-energy region, where influence of the
multiple scattering on the processes (the Landau-Pomeranchuk-Migdal (LPM)
effect) becomes essential. The integral characteristics: the radiation length
and the total probability of radiation and pair photoproduction are analyzed
under influence of the LPM effect.

</DOC>
<DOC>
<DOCNO> 70328 </DOCNO>
Lepton-Flavour-Violation in SUSY Models with and without R-parity


  We discuss Lepton-Flavour-Violating phenomena such as $\mu \to e \gamma$,
$\mu \to eee$, and $\mu \to e$ conversion in nuclei in SUSY models with and
without R-parity. We stress that experimental searches for all the LFV
processes are important to distinguish between the different models.

</DOC>
<DOC>
<DOCNO> 152153 </DOCNO>
Casimir energy and dilute dielectric ball


  General formalism of quantum field theory and addition theorem for Bessel
functions are applied to derive formula for Casimir-Polder energy of
interaction between a polarizable particle and a dilute dielectric ball. The
equivalence of dipole-dipole interaction and Casimir energy for dilute
homogeneous dielectrics is shown. A novel method is used to derive Casimir
energy of a dilute dielectric ball without divergences in calculations.
Physically realistic model of a dilute ball is discussed. Different approaches
to the calculation of Casimir energy of a dielectric ball are reviewed.

</DOC>
<DOC>
<DOCNO> 9100 </DOCNO>
Effects of interlayer coupling on the irreversibility lines of NbN/AlN


  We have studied the temperature dependence of the in-plane resistivity of
NbN/AlN multilayer samples with varying insulating layer thickness in magnetic
fields up to 7 Tesla parallel and perpendicular to the films. The upper
critical field shows a crossover from 2D to 3D behavior in parallel fields. The
irreversibility lines have the form (1-T/Tc)^alpha, where alpha varies from 4/3
to 2 with increasing anisotropy. The results are consistent with simultaneous
melting and decoupling transitions for low anisotropy sample, and with melting
of decoupled pancakes in the superconducting layers for higher anisotropy
samples.

</DOC>
<DOC>
<DOCNO> 178541 </DOCNO>
Dynamical constraints on phase transitions


  The numerical solutions of nonlocal and local Boltzmann kinetic equations for
the simulation of central heavy ion reactions are parameterized in terms of
time dependent thermodynamical variables in the Fermi liquid sense. This allows
one to discuss dynamical trajectories in phase space. The nonequilibrium state
is characterized by non-isobaric, non-isochoric etc. conditions, shortly called
iso-nothing conditions. Therefore a combination of thermodynamical observables
is constructed which allows one to locate instabilities and points of possible
phase transition in a dynamical sense. We find two different mechanisms of
instability, a short time surface - dominated instability and later a spinodal
- dominated volume instability. The latter one occurs only if the incident
energies do not exceed significantly the Fermi energy and might be attributed
to spinodal decomposition. In contrast the fast surface explosion occurs far
outside the spinodal region and pertains also in the cases where the system
develops too fast to suffer a spinodal decomposition and where the system
approaches equilibrium outside the spinodal region.

</DOC>
<DOC>
<DOCNO> 67837 </DOCNO>
Experimental Signatures of Split Fermions in Extra Dimensions


  The smallness and hierarchy of the fermion parameters could be explained in
theories with extra dimensions where doublets and singlets are localized at
slightly separated points. Scattering cross sections for collisions of such
fermions vanish exponentially at energies high enough to probe the separation
distance. This is because the separation puts a lower bound on the attainable
impact parameter in the collision. The NLC, and in particular the combination
of the e^+e^- and e^-e^- modes, can probe this scenario, even if the inverse
fermion separation is of order tens of TeVs.

</DOC>
<DOC>
<DOCNO> 102384 </DOCNO>
Wave scattering by small bodies of arbitrary shapes


  In this paper we review the results of the author on the theory of scalar and
vector wave scattering by small bodies of an arbitrary shape with the emphasis
on practical applicability of the formulas obtained and on the mathematical
rigor of the theory. For the scalar wave scattering by a single body, our main
results can be described as follows: (1) Analytical formulas for the scattering
amplitude for a small body of an arbitrary shape are obtained; dependence of
the scattering amplitude on the boundary conditions is described. (2) An
analytical formula for the scattering matrix for electromagnetic wave
scattering by a small body of an arbitrary shape is given. Applications of
these results are outlined (calculation of the properties of a rarefied medium;
inverse radio measurement problem; formulas for the polarization tensors and
capacitance). (3) The multi-particle scattering problem is analyzed and
interaction of the scattered waves is taken into account. For the
self-consistent field in a medium consisting of many particles ~ 10^{23},
integral-differential equations are found. The equations depend on the boundary
conditions on the particle surfaces. These equations offer a possibility of
solving the inverse problem of finding the medium properties from the
scattering data. For about 5 to 10 bodies the fundamental integral equations of
the theory can be solved numerically to study the interaction between the
bodies.

</DOC>
<DOC>
<DOCNO> 39661 </DOCNO>
Vacuum Alignment in Technicolor Theories-I. The Technifermion Sector


  We have carried out numerical studies of vacuum alignment in technicolor
models of electroweak and flavor symmetry breaking. The goal is to understand
alignment's implications for strong and weak CP nonconservation in quark
interactions. In this first part, we restrict our attention to the
technifermion sector of simple models. We find several interesting phenomena,
including (1) the possibility that all observable phases in the technifermions'
unitary vacuum-alignment matrix are integer multiples of \pi/N' where N' \le N,
the number of technifermion doublets, and (2) the possibility of exceptionally
light pseudoGoldstone technipions.

</DOC>
<DOC>
<DOCNO> 169644 </DOCNO>
Quantum tunneling dynamics using hydrodynamic trajectories


  In this paper we compute quantum trajectories arising from Bohm's causal
description of quantum mechanics. Our computational methodology is based upon a
finite-element moving least-squares method (MWLS) presented recently by Wyatt
and co-workers (Lopreore and Wyatt, Phys. Rev. Lett. {\bf 82}, 5190 (1999)).
This method treats the "particles" in the quantum Hamilton-Jacobi equation as
Lagrangian fluid elements which carry the phase, $S$, and density,
  $\rho$, required to reconstruct the quantum wavefunctions. Here, we compare
results obtained via the MWLS procedure to exact results obtained either
analytically or by numerical solution of the time dependent Schr\"odinger
equation. Two systems are considered: firstly, dynamics in a harmonic well and
secondly tunneling dynamics in a double well potential. In the case of
tunneling in the double well potential, the quantum potential acts to lower the
barrier separating the right and left hand sides of the well permitting
trajectories to pass from one side to another.
  However, as probability density passes from one side to the other, the
effective barrier begins to rise and eventually will segregate trajectories in
one side from the other. We note that the MWLS trajectories exhibited long time
stability in the purely harmonic cases. However, this stability was not evident
in the barrier crossing dynamics. Comparisons to exact trajectories obtained
via wave packet calculations indicate that the MWLS trajectories tend to
underestimate the effects of constructive and destructive interference effects.

</DOC>
<DOC>
<DOCNO> 178727 </DOCNO>
Production of $a_0$-mesons in the reactions $\pi N \to a_0 N$ and $p p


  We investigate the reactions $\pi N \to a_0 N$ and $p p \to d a_0^+$ near
threshold and at medium energies. An effective Lagragian approach and the Regge
pole model are applied to analyze different contributions to the cross section
of the reaction $\pi N \to a_0 N$. These results are used to calculate the
differential and total cross sections of the reaction $p p \to d a_0^+$ within
the framework of the two-step model in which two nucleons produce an
$a_0$-meson via $\pi$ -meson exchange and fuse to a deuteron. The necessity of
new measurements on $a_0$ production and branching fractions (of its decay to
the $K\bar K$ and $\pi\eta$ channels) is emphasized for clarifying the $a_0$
structure. Detailed predictions for the reaction $pp \to d a_0^+$ are presented
for the energy regime of the proton synchrotron COSY-J\"ulich.

</DOC>
<DOC>
<DOCNO> 70799 </DOCNO>
Electroweak Corrections to the Deacy $H^+\to W^+h$ in the Minimal


  We calculate the $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew}
m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the process
$H^+\to W^+h$ in the Minimal Supersymmetric Model. These corrections arise from
the virtual effects of the third family quaurks (top and bottom) and squarks
(top-squark and bottom-squark). We find that for $m_{H^+}>200$GeV at low
$\tan\beta(\leq 3)$, the corrections can increase the tree-level decay widths
and the branching radios more than 20% and 40%, respectively.

</DOC>
<DOC>
<DOCNO> 70531 </DOCNO>
Constraints on R-Parity violating stop couplings from flavor physics


  We perform a critical reassessment of the constraints on the R-parity and
baryon number violating (s)top couplings coming from flavor physics. In
particular, we study K0-K0bar mixing, including QCD corrections and a class of
diagrams that were neglected in previous analyses: both effects give sizeable
contributions. We explain how the resulting bounds can be translated into
constraints on individual couplings in the simplest class of flavor models,
based on U(1) horizontal symmetries. We finally discuss the implications for
the possibility of observing single superparticle production at the Tevatron.

</DOC>
<DOC>
<DOCNO> 12184 </DOCNO>
Parity (and time-reversal) anomaly in a semiconductor


  The physics of a parity anomaly, potentially observable in a narrow-gap
semiconductor, is revisited. Fradkin, Dagotto, and Boyanovsky have suggested
that a Hall current of anomalous parity can be induced by a Peierls distortion
on a domain wall. I argue that a perturbation inducing the parity anomaly must
break the time reversal symmetry, which rules out the Peierls distortion as a
potential cause. I list all possible perturbations that can generate the
anomaly.

</DOC>
<DOC>
<DOCNO> 120953 </DOCNO>
RXTE observations of Seyfert-2 galaxies: evidence for spectral


  We present a series of RXTE observations of the nearby obscured Seyfert
galaxies ESO103-G35, IC5063, NGC4507 and NGC7172. The period of monitoring
ranges from seven days for NGC7172 up to about seven months for ESO103-G035.
The spectra of all galaxies are well fit with a highly obscured (N_H>10^23
cm-2) power-law and an Fe line at 6.4 keV. We find strong evidence for the
presence of a reflection component in ESO103-G35 and NGC4507. The observed flux
presents strong variability on day timescales in all objects. Spectral
variability is also detected in the sense that the spectrum steepens with
increasing flux similar to the behaviour witnessed in some Seyfert-1 galaxies.

</DOC>
<DOC>
<DOCNO> 84244 </DOCNO>
Relational evolution of the degrees of freedom of generally covariant


  We study the classical and quantum dynamics of generally covariant theories
with vanishing a Hamiltonian and with a finite number of degrees of freedom. In
particular, the geometric meaning of the full solution of the relational
evolution of the degrees of freedom is displayed, which means the determination
of the total number of evolving constants of motion required. Also a method to
find evolving constants is proposed. The generalized Heinsenberg picture needs
M time variables, as opposed to the Heisenberg picture of standard quantum
mechanics where one time variable t is enough. As an application, we study the
parameterized harmonic oscillator and the SL(2,R) model with one physical
degree of freedom that mimics the constraint structure of general relativity
where a Schrodinger equation emerges in its quantum dynamics.

</DOC>
<DOC>
<DOCNO> 120340 </DOCNO>
A Possible Intrinsic Fluence-Duration Power-Law Relation in Gamma-ray


  We argue that the distributions of both the intrinsic fluence and the
intrinsic duration of the gamma-ray emission in gamma-ray bursts from the BATSE
sample are well represented by log-normal distributions, in which the intrinsic
dispersion is much larger than the cosmological time dilatation and redshift
effects. We perform separate bivariate log-normal distribution fits to the
BATSE short and long burst samples. The bivariate log-normal behavior results
in an ellipsoidal distribution, whose major axis determines an overall
statistical relation between the fluence and the duration. We show that this
fit provides evidence for a power-law dependence between the fluence and the
duration, with a statistically significant different index for the long and
short groups. We discuss possible biases which might affect this result, and
argue that the effect is probably real. This may provide a potentially useful
constraint for models of long and short bursts.

</DOC>
<DOC>
<DOCNO> 10211 </DOCNO>
Easy collective polarization switching in ferroelectrics


  The actual mechanism of polarization switching in ferroelectrics remains a
puzzle for many decades, since the usually estimated barrier for nucleation and
growth is insurmountable ("paradox of the coercive field"). To analyze the
mechanisms of the nucleation we consider the exactly solvable case of a
ferroelectric film with a "dead" layer at the interface with electrodes. The
classical nucleation is easier in this case but still impossible, since the
calculated barrier is huge. We have found that the {\em interaction} between
the nuclei is, however, long range, hence one has to study an {\em ensemble} of
the nuclei. We show that there are the ensembles of small (embryonic) nuclei
that grow {\em without the barrier}. We submit that the interaction between
nuclei is the key point for solving the paradox.

</DOC>
<DOC>
<DOCNO> 69715 </DOCNO>
Superconformal Symmetry, Supergravity and Cosmology


  We introduce the general N=1 gauge theory superconformally coupled to
supergravity. The theory has local SU(2,2|1) symmetry and no dimensional
parameters. The superconformal origin of the Fayet-Iliopoulos terms is
clarified. The phase of this theory with spontaneously broken conformal
symmetry gives various formulations of N=1 supergravity interacting with
matter, depending on the choice of the R-symmetry fixing.
  We have found that the locally superconformal theory is useful for describing
the physics of the early universe with a conformally flat FRW metric. Few
applications of superconformal theory to cosmology include the study of i)
particle production after inflation, particularly the non-conformal helicity
1/2 states of gravitino, ii) the super-Higgs effect in cosmology and the
derivation of the equations for the gravitino interacting with any number of
chiral and vector multiplets in the gravitational background with varying
scalar fields, iii) the weak coupling limit of supergravity and
gravitino-goldstino equivalence. This explains why gravitino production in the
early universe is not suppressed in the limit of weak gravitational coupling.
  We discuss the possible existence of an unbroken phase of the superconformal
theories, interpreted as a strong coupling limit of supergravity.

</DOC>
<DOC>
<DOCNO> 84908 </DOCNO>
A framework for perturbations and stability of differentially rotating


  The paper provides a new framework for the description of linearized
adiabatic lagrangian perturbations and stability of differentially rotating
newtonian stars. In doing so it overcomes problems in a previous framework by
Dyson and Schutz and provides the basis of a rigorous analysis of the stability
of such stars. For this the governing equation of the oscillations is written
as a first order system in time. From that system the generator of time
evolution is read off and a Hilbert space is given where it generates a
strongly continuous group. As a consequence the governing equation has a
well-posed initial value problem. The spectrum of the generator relevant for
stability considerations is shown to be equal to the spectrum of an operator
polynomial whose coefficients can be read off from the governing equation.
Finally, we give for the first time sufficient criteria for stability in the
form of inequalities for the coefficients of the polynomial. These show that a
negative canonical energy of the star does not necessarily indicate
instability. It is still unclear whether these criteria are strong enough to
prove stability for realistic stars.

</DOC>
<DOC>
<DOCNO> 10800 </DOCNO>
Density functional theory of spin-polarized disordered quantum dots


  Using density functional theory, we investigate fluctuations of the ground
state energy of spin-polarized, disordered quantum dots in the metallic regime.
To compare to experiment, we evaluate the distribution of addition energies and
find a convolution of the Wigner-Dyson distribution, expected for noniteracting
electrons, with a narrower Gaussian distribution due to interactions. The tird
moment of the total distribution is independent of interactions, and so is
predicted to decrease by a factor of 0.405 upon application of a magnetic field
which transforms from the Gaussian orthogonal to the Gaussian unitary ensemble.

</DOC>
<DOC>
<DOCNO> 14058 </DOCNO>
He-4 spectrum shift caused by He-3 admixture


  The shift of a maxon-roton He-4 excitation spectrum E via the He-3 admixture
is considered theoretically. The Bogoliubov formula for E(\rho, g) as a
function of Bose-condensate density \rho and of He-4/He-4 interaction g is used
as an element of partition function formalism of the whole system, presented in
the form of a path (functional) integral. The dependence of \rho on g,
He-4/He-3 interaction \lambda as well as on the pressure P, induced by He-3
admixture, is taken into account. The new model of g, suitable for analytical
calculations, is used for a description of a change of P within the constant
volume. The cases of positive and negative shifts are found as the result of
competition between interactions g and \lambda.

</DOC>
<DOC>
<DOCNO> 8925 </DOCNO>
Random Networks of Spiking Neurons: Instability in the Xenopus tadpole


  A large network of integrate-and-fire (IF) neurons is studied analytically
when the synaptic weights are independently randomly distributed according to a
gaussian distribution with arbitrary mean. The relevant order parameters are
identified, and it is shown that such network is statistically equivalent to an
ensemble of independent IF neurons with each input signal given by the sum of a
self-interaction deterministic term and a gaussian coloured noise. The model is
able to reproduce the quasi-synchronous oscillations, and the dropout of their
frequency, of the CNS neurons of the swimming Xenopus tadpole. The cause of the
instability of low firing-rate self-sustained activity is identified and
explained. Predictions from the model are proposed for future experiments.

</DOC>
<DOC>
<DOCNO> 9318 </DOCNO>
The Elastic Behavior of Entropic "Fisherman's Net"


  A new formalism is used for a Monte Carlo determination of the elastic
constants of a two-dimensional net of fixed connectivity. The net is composed
of point-like atoms each of which is tethered to six neighbors by a bond
limiting the distance between them to a certain maximal separation, but having
zero energy at all smaller lengths. We measure the elastic constants for many
values of the ratio $\gamma$ between the maximal and actual extensions of the
net. When the net is very stretched ($\gamma\sim 1$), a simple transformation
maps the system into a triangular hard disks solid, and we show that the
elastic properties of both systems, coincide. We also show that the crossover
to a Gaussian elastic behavior, expected for the non-stressed net, occurs when
the net is more loose ($\gamma\sim 3$).

</DOC>
<DOC>
<DOCNO> 13471 </DOCNO>
Quantum generalized constant coupling model for geometrically frustrated


  A generalized constant coupling approximation for quantum geometrically
frustrated antiferromagnets is presented. Starting from a frustrated unit, we
introduce the interactions with the surrounding units in terms of an internal
effective field which is fixed by a self consistency condition. Results for the
static magnetic susceptibility and specific heat are compared with previous
results in the framework of this same model for the classical limit. The range
of applicability of the model is discussed.

</DOC>
<DOC>
<DOCNO> 13422 </DOCNO>
Breakdown of Conformal Invariance at Strongly Random Critical Points


  We consider the breakdown of conformal and scale invariance in random systems
with strongly random critical points. Extending previous results on
one-dimensional systems, we provide an example of a three-dimensional system
which has a strongly random critical point. The average correlation functions
of this system demonstrate a breakdown of conformal invariance, while the
typical correlation functions demonstrate a breakdown of scale invariance. The
breakdown of conformal invariance is due to the vanishing of the correlation
functions at the infinite disorder fixed point, causing the critical
correlation functions to be controlled by a dangerously irrelevant operator
describing the approach to the fixed point. We relate the computation of
average correlation functions to a problem of persistence in the RG flow.

</DOC>
<DOC>
<DOCNO> 122537 </DOCNO>
The Importance of Fourier Phases for the Morphology of Gravitational


  The phases of the Fourier modes appearing in a plane-wave expansion of
cosmological density fields play a vital role in determining the morphology of
gravitationally-developed clustering. We demonstrate this qualitatively and
quantitatively using simulations. In particular, we use cross-correlation and
rank-correlation techniques to quantify the agreement between a simulated
distribution and phase-only reconstructions. The phase-only reconstructions
exhibit a high degree of correlation with the original distributions, showing
how meaningful spatial reconstruction of cosmological density fields depends
more on phase accuracy than on amplitudes.

</DOC>
<DOC>
<DOCNO> 121785 </DOCNO>
Details of the mass--temperature relation for clusters of galaxies


  We present results on the total mass and temperature determination using two
samples of clusters of galaxies. One sample is constructed with emphasis on the
completeness of the sample, while the advantage of the other is the use of the
temperature profiles, derived with ASCA. We obtain remarkably similar fits to
the M-T relation for both samples, with the normalization and the slope
significantly different from both prediction of self-similar collapse and
hydrodynamical simulations. We discuss the origin of these discrepancies and
also combine the X-ray mass with velocity dispersion measurements to provide a
comparison with high-resolution dark matter simulations. Finally, we discuss
the importance of a cluster formation epoch in the observed M-T relation.

</DOC>
<DOC>
<DOCNO> 169766 </DOCNO>
Comment on `Quantum Games and Quantum Strategies'


  In a recent paper, Eisert et al. presented a quantum mechanical
generalization of Prisoner's Dilemma. They asserted that the maximally
entangled game exhibits a unique Nash equilibrium which yields a pay-off
equivalent to cooperative behaviour. In this comment we show that their
observation is incorrect: there is no Nash equilibrium in the space of
deterministic quantum strategies.

</DOC>
<DOC>
<DOCNO> 152449 </DOCNO>
De Rham-Kodaira's Theorem and Dual Gauge Transformations


  A general action is proposed for the fields of $q$-dimensional differential
form over the compact Riemannian manifold of arbitrary dimensions. Mathematical
tools are based on the well-known de Rham-Kodaira decomposing theorem on
harmonic integral. A field-theoretic action for strings, $p$-branes and
high-spin fields is naturally derived. We also have, naturally, the generalized
Maxwell equations with an electromagnetic and monopole current on a curved
space-time. A new type of gauge transformations ({\it dual} gauge
transformations) plays an essential role for coboundary $q$-forms.

</DOC>
<DOC>
<DOCNO> 67853 </DOCNO>
Can extended duality uniquely explain the dilepton data in HICs at SPS?


  Extended duality is used to explain the dilepton data of heavy-ion
experiments at CERN-SPS. Taking into account the background contributions
(hadronic cocktail, Drell-Yan, semileptonic decays of open charm) the spectral
shapes of the CERES, NA38/50 and HELIOS-3 data in experiments with lead and
sulfur beams can be well described, however, the normalizations of the sulfur
beam data are problematic.

</DOC>
<DOC>
<DOCNO> 39834 </DOCNO>
Search for "light" magnetic monopoles


  We propose to implement one passive nuclear track detector array of 400 m^2
at the Chacaltaya High Altitude Laboratory (5230 m a.s.l.). The main purposes
of the experiment concern the searches for magnetic monopoles of relatively low
masses at the Parker bound level, searches for low mass nuclearites and
searches for some supersymmetric dark matter candidates (Q-balls).

</DOC>
<DOC>
<DOCNO> 169670 </DOCNO>
Perspectives on Nonlinearity in Quantum Theory


  An enlarged group G of nonlinear transformations, modeled on the general
linear group GL(2,R), leads to a beautiful, apparently unremarked symmetry
between the wave function's phase and the logarithm of its amplitude. Equations
Doebner and I earlier proposed are embedded in a wider, natural family of
nonlinear time-evolution equations, on which G acts as a gauge group (leaving
physical observations invariant). There exist G-invariant quantities that
reduce to the usual probability density and flux for linearizable quantum
theories in a particular gauge.

</DOC>
<DOC>
<DOCNO> 122550 </DOCNO>
First XMM-Newton observations of an isolated neutron star:


  We present the high resolution spectrum of the isolated neutron star
RXJ0720.4-3125, obtained with the Reflection Grating Spectrometer on
XMM-Newton, complemented with the broad band spectrum observed with the EPIC PN
camera. The spectrum appears smooth, with no evidence for strong photospheric
absorption or emission features. We briefly discuss the implications of our
failure to detect structure in the spectrum.

</DOC>
<DOC>
<DOCNO> 71390 </DOCNO>
On Wolfgang Pauli's most important contributions to physics


  After some brief biographical notes, Wolfgang Pauli's main contributions to
general relativity, quantum theory, quantum field theory, and elementary
particle physics are reviewed. A detailed description is given how Pauli
descovered - before the advent of the new quantum mechanics - his exclusion
principle.

</DOC>
<DOC>
<DOCNO> 152164 </DOCNO>
The Renormalization of the Non-Abelian Gauge Theories in the Causal


  We consider the gauge invariance of the standard Yang-Mills model in the
framework of the causal approach of Epstein-Glaser and Scharf and determine the
generic form of the anomalies. The method used is based Epstein-Glaser approach
to renormalization theory. In the case of quantum electrodynamics we obtain
quite easily the absence of anomalies in all orders.

</DOC>
<DOC>
<DOCNO> 118456 </DOCNO>
L1551NE - Discovery of a Binary Companion


  L1551NE is a very young (class 0 or I) low-mass protostar located close to
the well-studied L1551 IRS5. We present here evidence, from 1.3mm continuum
interferometric observations at ~1'' resolution, for a binary companion to
L1551NE. The companion, whose 1.3mm flux density is ~1/3 that of the primary
component, is located 1.43'' (~230 A.U. at 160pc) to the southeast. The
millimeterwave emission from the primary component may have been just barely
resolved, with deconvolved size ~0.82"x0.70" (~131x112 A.U.). The companion
emission was unresolved (<100 A.U.). The pair is embedded within a flattened
circum-binary envelope of size ~5.4'' x 2.3'' (~860 x 370 A.U.). The masses of
the three components (i.e. from the cicumstellar material of the primary star
and its companion, and the envelope) are approximately 0.044, 0.014 and 0.023
Mo respectively.

</DOC>
<DOC>
<DOCNO> 121102 </DOCNO>
An unresolved X-ray source inside the supernova remnant RCW 86


  We report on the discovery of an unresolved X-ray source inside the supernova
remnant G315.4-2.3 (RCW 86). The source is located 7' to the Southwest of the
geometrical centre and may be close to the actual explosion centre of the
supernova, which makes this a candidate for the stellar remnant associated with
RCW 86. However, the presence of a possible optical counterpart with $V \sim
14$ at 3" from the X-ray position and evidence for long term variability means
that the source is probably an active star. A better X-ray position and better
X-ray spectroscopy along with an identification of the optical source are
needed to exclude the X-ray source as a neutron star candidate.

</DOC>
<DOC>
<DOCNO> 120442 </DOCNO>
Galaxy-dark matter correlations applied to galaxy-galaxy lensing:


  We use semi-analytic models of galaxy formation combined with high resolution
N-body simulations to make predictions for galaxy-dark matter correlations and
apply them to galaxy-galaxy lensing. We analyze cross-correlation spectra
between the dark matter and different galaxy samples selected by luminosity,
color or star formation rate. We compare the predictions to the recent
detection by SDSS. We show that the correlation amplitude and the mean
tangential shear depend strongly on the luminosity of the sample on scales
below 1 Mpc, reflecting the correlation between the galaxy luminosity and the
halo mass. The cross-correlation cannot however be used to infer the halo
profile directly because different halo masses dominate on different scales and
because not all galaxies are at the centers of the corresponding halos. We
compute the redshift evolution of the cross-correlation amplitude and compare
it to those of galaxies and dark matter. We also compute the galaxy-dark matter
correlation coefficient and show it is close to unity on scales above r > 1 Mpc
for all considered galaxy types. This would allow one to extract the bias and
the dark matter power spectrum on large scales from the galaxy and galaxy-dark
matter correlations.

</DOC>
<DOC>
<DOCNO> 40139 </DOCNO>
Four-neutrino oscillations and the solar neutrino problem


  We perform a fit of solar neutrino data in the framework of the two
four-neutrino schemes that are compatible with the results of all neutrino
oscillation experiments. These schemes allow simultaneous transitions of solar
nu_e's into active nu_mu's, nu_tau's and sterile nu_s. The data imply that the
SMA solution is valid for any combination of nu_e->active and nu_e->sterile
transitions, whereas the LMA, LOW and VO solutions disappear when nu_e->nu_s
transitions are dominant.

</DOC>
<DOC>
<DOCNO> 80649 </DOCNO>
New Domain-Wall Fermion Actions


  In perturbation theory, the wave function of domain-wall quarks decreases
exponentially with the fifth coordinate. We show that, regardless of the
quark's own momentum, the fall-off rate of the one-loop wave function is equal
to the slowest rate encountered at tree-level for any lattice four-momentum. We
propose new domain-wall actions involving beyond-nearest neighbor couplings in
the four physical dimensions, for which the perturbative wave function
decreases much faster. It is hoped that the new actions may preserve the good
chiral properties of domain-wall fermions up to larger values of the lattice
spacing.

</DOC>
<DOC>
<DOCNO> 119924 </DOCNO>
Re-processing the Hipparcos Transit Data and Intermediate Astrometric


  The Intermediate Astrometric Data (IAD) and Transit Data (TD) made available
by ESA after the Hipparcos mission make it possible to re-process the
observations of any Hipparcos entry. This paper illustrates how TD and IAD may
be used in conjunction with the orbital parameters of spectroscopic binaries to
improve the astrometric parameters of binaries considered as single stars in
the original reduction process. That approach has been applied to 81 dwarf
barium stars, strong and mild barium stars, CH stars, and Tc-poor S stars for
which spectroscopic orbits became available recently. Among these 81 systems,
23 yield reliable astrometric orbits, thus making it possible to evaluate on
real data the impact of an unrecognized orbital motion on the proper motion
(Wielen, 1997, A&A 325, 367). Comparison of the proper motion from the
Hipparcos catalogue with that re-derived in the present work indicates that the
former are indeed far off the present value for binaries with periods in the
range 3 to about 8 years. Hipparcos parallaxes of unrecognized spectroscopic
binaries turn out to be reliable, except for systems with periods close to 1
year, as expected. Finally, we show that, even when a complete orbital
revolution was observed by Hipparcos, the inclination is unfortunately seldom
precise.

</DOC>
<DOC>
<DOCNO> 100155 </DOCNO>
A naive question about quantum groups


  The category O of BGG can be thought of as a category of sheaves over the
flag variety F in the sense that the algebra E of self-extensions of the
trivial object of O is isomorphic to the cohomology algebra of the flag
variety. A deformation of O' - giving rise to a "new" algebra E' - can be
thought of as a (possibly noncommutative) deformation F' of F. The mythic
variety F', being a deformation of F, should have the same homotopy type as F,
and E' should therefore be isomorphic to E.

</DOC>
<DOC>
<DOCNO> 121068 </DOCNO>
Revealing deuterium Balmer lines in HII regions with VLT-UVES


  The search for deuterium Balmer lines with VLT-UVES is reported in HII
regions of the Galaxy and the Magellanic Clouds. The DI lines appear as faint,
narrow emission features in the blue wings of the HI Balmer lines and can be
distinguished from high-velocity HI emission. The previous identification to
deuterium is re-inforced beyond doubt. The detection of D-alpha and D-beta in
Orion (Hebrard et al. 2000) is confirmed and deuterium lines are now detected
up to at least D-eta. The UVES observations provide the first detection of
Balmer DI lines in four new HII regions (M 8, M 16, M 20, and DEM S 103 in
SMC), demonstrating that these lines are of common occurence.

</DOC>
<DOC>
<DOCNO> 85139 </DOCNO>
Motions and world-line deviations in Einstein-Maxwell theory


  We examine the motion of charged particles in gravitational and
electro-magnetic background fields. We study in particular the deviation of
world lines, describing the relative acceleration between particles on
different space-time trajectories. Two special cases of background fields are
considered in detail: (a) pp-waves, a combination of gravitational and
electro-magnetic polarized plane waves travelling in the same direction; (b)
the Reissner-Nordstr{\o}m solution. We perform a non-trivial check by computing
the precession of the periastron for a charged particle in the
Reissner-Nordstr{\o}m geometry both directly by solving the geodesic equation,
and using the world-line deviation equation. The results agree to the order of
approximation considered.

</DOC>
<DOC>
<DOCNO> 122129 </DOCNO>
A High Resolution Method for Measuring Cosmic Ray Composition beyond 10


  The accurate determination of the elemental composition of cosmic rays at
high energies is expected to provide crucial clues on the origin of these
particles. Previous direct measurements of composition have been limited by
experiment collecting power, resulting in marginal statistics above $10^{14}$
eV, precisely the region where the ``knee'' of the cosmic-ray energy spectrum
is starting to develop. In contrast, indirect measurements using extensive air
showers can produce sufficient statistics in this region but generate elemental
measurements which have relatively large uncertainties. Here we discuss a
technique which has become possible through the use of modern ground-based
Cerenkov imaging detectors. We combine a measurement of the Cerenkov light
produced by the incoming cosmic-ray nucleus in the upper atmosphere with an
estimate of the total nucleus energy produced by the extensive air shower
initiated when the particle interacts deeper in the atmosphere. The emission
regions prior to and after the first hadronic interaction can be separated by
an imaging Cerenkov system with sufficient angular and temporal resolution.
Monte Carlo simulations indicate an expected charge resolution of $\Delta Z/Z
<5%$ for incident iron nuclei in the region of the ``knee'' of the cosmic-ray
energy spectrum. This technique also has the intriguing possibility to
unambiguously discover nuclei heavier than iron at energies above 10$^{14}$ eV.
The identification and rejection of background produced by charged particles in
ground based gamma-ray telescopes is also discussed.

</DOC>
<DOC>
<DOCNO> 7713 </DOCNO>
Decay on several sorts of heterogeneous centers: Special monodisperse


  The situation of the metastable phase decay on the several types of
heterogeneous centers is considered. This publication directly continues "
cond-mat@xxx.lanl.gov get 0001104 ", " cond-mat@xxx.lanl.gov get 0001108" and "
cond-mat@xxx.lanl.gov get 0001112 " . In this section the approximation od the
essential asymptotes is formulated. This approximation is more simple than the
floating monodisperse approximation and the special monodisperse approximation.
The evident advantage of this approximation is the absence of the exponential
nonlinearity.

</DOC>
<DOC>
<DOCNO> 116797 </DOCNO>
Slow light


  We present a brief classical discussion of a process to reduce the group
velocity of an electromagnetic pulse by many orders of magnitude.

</DOC>
<DOC>
<DOCNO> 11143 </DOCNO>
Isotropic Conductivity of Two-Dimensional Three-Component Symmetric


  The effective dc-conductivity problem of isotropic, two-dimensional (2D),
three-component, symmetric, regular composites is considered. A simple cubic
equation with one free parameter for $\sigma_{e}(\sigma_1,\sigma_2,\sigma_3)$
is suggested whose solutions automatically have all the exactly known
properties of that function. Numerical calculations on four different
symmetric, isotropic, 2D, three-component, regular structures show a
non-universal behavior of $\sigma_{e}(\sigma_1,\sigma_2,\sigma_3)$ with an
essential dependence on micro-structural details, in contrast with the
analogous two-component problem. The applicability of the cubic equation to
these structures is discussed. An extension of that equation to the description
of other types of 2D three-component structures is suggested, including the
case of random structures.
  Pacs: 72.15.Eb, 72.80.Tm, 61.50.Ah

</DOC>
<DOC>
<DOCNO> 150855 </DOCNO>
Nucleation at finite temperature beyond the superminispace model


  The transition from the quantum to the classical regime of the nucleation of
the closed Robertson-Walker Universe with spacially homogeneous matter fields
is investigated with a perturbation expansion around the sphaleron
configuration. A criterion is derived for the occurrence of a first-order type
transition, and the related phase diagram for scalar and vector fields is
obtained. For scalar fields both the first and second order transitions can
occur depending on the shape of the potential barrier. For a vector field, here
that of an O(3) nonlinear $\sigma$-model, the transition is seen to be only of
the first order.

</DOC>
<DOC>
<DOCNO> 72282 </DOCNO>
H-->WW as the discovery mode for a light Higgs boson


  The production cross section for a m_H=115 GeV, SM Higgs boson in weak boson
fusion at the LHC is sizable. However, the branching fraction for H-->WW is
expected to be relatively small. The signal, with its two forward jets, is
sufficiently different from the main backgrounds that a signal to background
ratio of better than 1:1 can nevertheless be obtained, with large enough rate
to allow for a 5 sigma signal with 35 fb^{-1} of data. The H-->WW signal in
weak boson fusion may thus prove to be the discovery mode for the Higgs boson
at the LHC.

</DOC>
<DOC>
<DOCNO> 10191 </DOCNO>
Interface resistance of disordered magnetic multilayers


  We study the effect of interface disorder on the spin-dependent interface
resistances of Co/Cu, Fe/Cr and Au/Ag multilayers using a newly developed
method for calculating transmission matrices from first-principles. The
efficient implementation using tight-binding linear-muffin-tin orbitals allows
us to model interface disorder using large lateral supercells whereby specular
and diffuse scattering are treated on an equal footing. Without introducing any
free parameters, quantitative agreement with experiment is obtained. We predict
that disorder {\it reduces} the majority-spin interface resistance of
Fe/Cr(100) multilayers by a factor 3.

</DOC>
<DOC>
<DOCNO> 12069 </DOCNO>
Ferromagnetism in a (001), (110), and (111)-oriented Ru mololayer on Ag,


  We have studied the magnetic behavior of a 4d transition metal Ru monolayer
(ML) on different substrates and orientations. In the ground state, a Ru-ML is
expected to be ferromagnetic on Ag(001) and Au(001) with a magnetic moment
$(\mu) $ of 1.73 Bohr magnetons $(\mu_{B}) $ in both cases. On Cu(001), a Ru-ML
is not magnetic. In this paper, we study the magnetic behavior of a Ru-ML at
other orientations, i.e., (110) and (111). We found magnetism on Au (111), and
Ag (111) ($\mu\thicksim 1.3\mu_{B}$ for both) but no magnetic activity on a Cu
substrate in any orientation. Further, we found that on Ag(110), a Ru-ML is
ferromagnetic with $\mu =1.3\mu_{B}$. On Au(110), a Ru-ML is not magnetic.
Since on the (001) and (111) orientations a Ru-ML has about the same magnetic
activity on Ag as on Au, we found surprising the behavior in the (110)
orientation. We analyze it in detail in the final part of the paper. We found
that there exists a metastable ferromagnetic state, in this case, and that a
Ru-ML becomes ferromagnetic under a small expansion of the Au-lattice. This is
not the case for Cu.

</DOC>
<DOC>
<DOCNO> 152194 </DOCNO>
Complex Gravity and Noncommutative Geometry


  The presence of a constant background antisymmetric tensor for open strings
or D-branes forces the space-time coordinates to be noncommutative. An
immediate consequence of this is that all fields get complexified. By applying
this idea to gravity one discovers that the metric becomes complex. Complex
gravity is constructed by gauging the symmetry $U(1,D-1)$. The resulting action
gives one specific form of nonsymmetric gravity. In contrast to other theories
of nonsymmetric gravity the action is both unique and gauge invariant. It is
argued that for this theory to be consistent one must prove the existence of
generalized diffeomorphism invariance. The results are easily generalized to
noncommutative spaces.

</DOC>
<DOC>
<DOCNO> 169714 </DOCNO>
Generalised coherent states and the diagonal representation for


  We consider the problem of existence of the diagonal representation for
operators in the space of a family of generalized coherent states associated
with an unitary irreducible representation of a (compact) Lie group. We show
that necessary and sufficient conditions for the possibility of such a
representation can be obtained by combining Clebsch-Gordan theory and the
reciprocity theorems associated with induced unitary group representation.
 Applications to several examples involving $SU(2),$ $SU(3),$ and the
Heisenberg-Weyl group are presented, showing that there are simple examples of
generalized coherent states which do not meet these conditions. Our results are
relevant for phase-space description of quantum mechanics and quantum state
reconstruction problems.

</DOC>
<DOC>
<DOCNO> 39933 </DOCNO>
Measurements of the Sigma_c^0 and Sigma_c^{++} Mass Splittings


  Using a high statistics sample of photoproduced charmed particles from the
FOCUS experiment at Fermilab (FNAL-E831), we measure the mass splittings of the
charmed baryons Sigma_c^0 and Sigma_c^{++}. We find M(Sigma_c^0 - Lambda_c^+) =
167.38 +/- 0.21 +/- 0.13 MeV/c^2 and M(Sigma_c^++ - Lambda_c^+) = 167.35 +/-
0.19 +/- 0.12 MeV/c^2 with samples of 362 +/- 36 and 461 +/- 39 events,
respectively. We measure the isospin mass splitting M(Sigma_c^++ - Sigma_c^0)
to be -0.03 +/- 0.28 +/- 0.11 Mev/c^2. The first errors are statistical and the
second are systematic.

</DOC>
<DOC>
<DOCNO> 69526 </DOCNO>
Semi-inclusive vector meson production in DIS


  We analyze one-particle inclusive DIS in the case when a spin-1 hadron (such
as a vector meson) is observed in the final state. We consider only leading
order contributions in 1/Q, but we include transverse momentum of partons.
Several new fragmentation functions appear in cross sections. One of them can
be measured in connection with the transverse-spin disbtribution function h_1.

</DOC>
<DOC>
<DOCNO> 120758 </DOCNO>
On the peculiar X-ray properties of the bright nearby radio-quiet quasar


  BeppoSAX and ASCA observations of the nearby (z=0.184), high-luminosity,
radio-quiet quasar PDS456 are presented. The X-ray spectrum is characterized by
a prominent ionized edge at 8-9 keV (originally discovered by RXTE, Reeves et
al. 2000) and by a soft excess below 1.5 keV. The lack of any significant iron
K alpha emission line suggests for the edge an origin from line-of-sight
material rather than from reflection from a highly ionized accretion disc. The
hard X-ray continuum is indeed well modelled by transmission through a
highly-ionized medium with a large column density (N_H warm = 4.5 x 10^24
cm^-2) plus an additional cold absorber with a lower column density (N_H cold =
2.7 x 10^22 cm^-2).

</DOC>
<DOC>
<DOCNO> 117912 </DOCNO>
X-ray absorption lines in the Seyfert 1 galaxy NGC 5548 discovered with


  We present for the first time a high-resolution X-ray spectrum of a Seyfert
galaxy. The Chandra-LETGS spectrum of NGC 5548 shows strong, narrow absorption
lines from highly ionised species (the H-like and He-like ions of C, N, O, Ne,
Na, Mg, Si, as well as Fe XIV--XXI). The lines are blueshifted by a few hundred
km/s. The corresponding continuum absorption edges are weak or absent. The
absorbing medium can be modelled by an outflowing, thin and warm shell in
photoionization equilibrium. The absorption lines are similar to lower
ionization absorption lines observed in the UV, although these UV lines
originate from a different location or phase of the absorbing medium.
Redshifted with respect to the absorption lines, emission from the O VIII Lyman
alpha line as well as the O VII triplet is visible. The flux of these lines is
consistent with emission from the absorbing medium. The O VII triplet intensity
ratios demonstrate that photoionization dominates and yield an upper limit to
the electron density.

</DOC>
<DOC>
<DOCNO> 84951 </DOCNO>
Three-dimensional adaptive evolution of gravitational waves in numerical


  Adaptive techniques are crucial for successful numerical modeling of
gravitational waves from astrophysical sources such as coalescing compact
binaries, since the radiation typically has wavelengths much larger than the
scale of the sources. We have carried out an important step toward this goal,
the evolution of weak gravitational waves using adaptive mesh refinement in the
Einstein equations. The 2-level adaptive simulation is compared with unigrid
runs at coarse and fine resolution, and is shown to track closely the features
of the fine grid run.

</DOC>
<DOC>
<DOCNO> 117684 </DOCNO>
Asteroseismology and Oblique Pulsator Model of Beta Cephei


  We discuss the oscillation features of Beta Cephei, which is a magnetic star
in which the magnetic axis seems to be oblique to the rotation axis. We
interpret the observed equi-distant fine structures of the frequency spectrum
as a manifestation of a magnetic perturbation of an eigenmode, which would be a
radial mode in the absence of the magnetic field. Besides these frequency
components, we interpret another peak in the frequency spectrum as an
independent quadrupole mode. By this mode identification, we deduce the mass,
the evolutionary stage, the rotational frequency, the magnetic field strength,
and the geometrical configuration of Beta Cephei.

</DOC>
<DOC>
<DOCNO> 152536 </DOCNO>
Applications of Exact Renormalization Group techniques to the


  Exact Renormalization Group techniques are applied to supersymmetric models
in order to get some insights into the low energy effective actions of such
theories. Starting from the ultra-violet finite mass deformed N=4
supersymmetric Yang-Mills theory, one varies the regularising mass and
compensates for it by introducing an effective Wilsonian action. (Polchinski's)
Renormalization Group equation is modified in an essential way by the presence
of rescaling (a.k.a. Konishi) anomaly, which is responsible for the
beta-function. When supersymmetry is broken up to N=1 the form of effective
actions in terms of massless fields is quite reasonable, while in the case of
the N=2 model we appear to have problems related to instantons.

</DOC>
<DOC>
<DOCNO> 68589 </DOCNO>
Novel Relations between Lepton and Quark Mixings


  A novel relation is found which gives the 2-3 lepton mixing angle in terms of
quark masses and CKM mixing: \tan\theta_{\mu\tau}=(m_b/m_s)V_{cb}. This
relation, which is remarkably in good agreement with the quark data and the
large lepton mixing recently observed, is a kind of SO(10) GUT relation similar
to the celebrated bottom-tau mass ratio in SU(5). The GUT models in which this
relation hold should have a `twisted SO(10)' structure between the second and
third generations, in order to really explain the large lepton mixing, or
equivalently, the right-hand side of the relation.

</DOC>
<DOC>
<DOCNO> 152317 </DOCNO>
A new Dirac-type equation for tachyonic neutrinos


  Based on experimental evidences supporting the hypothesis that neutrinos
might be tachyonic fermions, a new Dirac-type equation is proposed and a
spin-1/2 tachyonic quantum theory is developed. The new Dirac-type equation
provides a solution for the puzzle of negative mass-square of neutrinos. This
equation can be written in two spinor equations coupled together via nonzero
mass while respecting the maximum parity violation, and it reduces to one Weyl
equation in the massless limit. Some peculiar features of tachyonic neutrino
are discussed in this theoretical framework.

</DOC>
<DOC>
<DOCNO> 170482 </DOCNO>
Bunching and antibunching from single NV color centers in diamond


  We investigate correlations between fluorescence photons emitted by single
N-V centers in diamond with respect to the optical excitation power. The
autocorrelation function shows clear photon antibunching at short times,
proving the uniqueness of the emitting center. We also report on a photon
bunching effect, which involves a trapping level. An analysis using
rate-equations for the populations of the N-V center levels shows the intensity
dependence of the rate equation coefficients.

</DOC>
<DOC>
<DOCNO> 7669 </DOCNO>
Theoretical Investigation of Water Formation on Rh and Pt Surfaces


  In this report we present a theoretical investigation of the potential-energy
diagram for water formation from adsorbed O and H species on Rh(111) and
Pt(111) surfaces. The study is based on accurate first-principles calculations
applying density-functional theory. Our results are compared to the
potential-energy diagram for this reaction inferred from experimental data by
Hickman and Schmidt The calculations essentially reproduce the scheme of
Hickman and Schmidt for water formation on Rh(111) with the important
difference that the OH molecule is significantly more stable than assumed by
Hickman and Schmidt. On Pt(111) surfaces, however, the calculations predict a
barrier to OH formation very similar to that found on Rh(111). In particular,
the calculated barrier to OH formation of about 20 kcal/mol seems to contradict
the small 2.5 kcal/mol barrier assumed in the Hickman-Schmidt scheme and the
observed large rate of water formation on Pt. A possible explanation for the
apparent discrepancy between the large calculated barrier for OH formation on
Pt and the experimentally observed rapid formation of water even at low
temperatures is that the active sites for water formation on Pt are at "defect"
sites and not on the ideally flat terraces. A similar conclusion has been
reached by Verheij and Comsa, who did detailed experimental work on water
formation on Pt surfaces. Analyzing our results, we develop an explicit picture
of the interaction processes governing the formation of OH groups. This picture
rationalizes the calculated weak dependence of OH formation on substrate
material. An important conclusion from this work is that good catalysts for the
partial oxidation of hydrocarbons should resist defect formation at their
surfaces.

</DOC>
<DOC>
<DOCNO> 118004 </DOCNO>
Physics in Ultra-strong Magnetic Fields


  In magnetic fields stronger than B_Q = 4.4 X 10^13 Gauss, an electron's
Landau excitation energy exceeds its rest energy. I review the physics of this
strange regime and some of its implications for the crusts and magneto- spheres
of neutron stars. In particular, I describe how ultra-strong fields
  >> render the vacuum birefringent and capable of distorting and
   magnifying images ("magnetic lensing");
  >> change the self-energy of electrons: as B increases they are first
   slightly lighter than $m_e$, then slightly heavier;
  >> cause photons to rapidly split and merge with each other;
  >> distort atoms into long, thin cylinders and molecules into strong,
   polymer-like chains;
  >> enhance the pair density in thermal pair-photon gases; >> strongly
suppress photon-electron scattering, and >> drive the vacuum itself unstable,
at extremely large B.
  In a concluding section, I discuss recent observations of the spindown
histories of soft gamma repeaters and anomalous X-ray pulsars. The magnetar
model gives a promising framework for understanding these data.

</DOC>
<DOC>
<DOCNO> 40018 </DOCNO>
Beam-Generated Detector Backgrounds at CESR


  The CESR/CLEO Phase II interaction region is described. The operational
experience with beam-generated detector backgrounds is reviewed. The status of
our understanding of beam-generated detector backgrounds at CESR is described
and comparisons of background measurements with simulation predictions are
presented.

</DOC>
<DOC>
<DOCNO> 8409 </DOCNO>
Diffusion limited aggregation as a Markovian process. Part I:


  Cylindrical lattice Diffusion Limited Aggregation (DLA), with a narrow width
N, is solved using a Markovian matrix method. This matrix contains the
probabilities that the front moves from one configuration to another at each
growth step, calculated exactly by solving the Laplace equation and using the
proper normalization. The method is applied for a series of approximations,
which include only a finite number of rows near the front. The matrix is then
used to find the weights of the steady state growing configurations and the
rate of approaching this steady state stage. The former are then used to find
the average upward growth probability, the average steady-state density and the
fractal dimensionality of the aggregate, which is extrapolated to a value near
1.64.

</DOC>
<DOC>
<DOCNO> 123042 </DOCNO>
A new population of WIMPs in the solar system and indirect detection


  A new Solar System population of Weakly Interacting Massive Particle (WIMP)
dark matter has been proposed to exist. We investigate the implications of this
population on indirect signals in neutrino telescopes (due to WIMP
annihilations in the Earth) for the case when the WIMP is the lightest
neutralino of the MSSM, the minimal supersymmetric extension of the standard
model. The velocity distribution and capture rate of this new population is
evaluated and the flux of neutrino-induced muons from the center of the Earth
in neutrino telescopes is calculated. We show that the effects of the new
population can be crucial for masses around 60-120 GeV, where enhancements of
the predicted muon flux from the center of the Earth by up to a factor of 100
compared to previously published estimates occur. As a result of the new WIMP
population, neutrino telescopes should be able to probe a much larger region of
parameter space in this mass range.

</DOC>
<DOC>
<DOCNO> 11972 </DOCNO>
Shape deformations and angular momentum transfer in trapped


  Angular momentum can be transferred to a trapped Bose-Einstein condensate by
distorting its shape with an external rotating field, provided the rotational
frequency is larger than a critical frequency fixed by the energy and angular
momentum of the excited states of the system. By using the Gross-Pitaevskii
equation and sum rules, we explore the dependence of such a critical frequency
on the multipolarity of the excitations and the asymmetry of the confining
potential. We also discuss its possible relevance for vortex nucleation in
rotating traps.

</DOC>
<DOC>
<DOCNO> 150662 </DOCNO>
AdS/CFT Correspondence and Type 0 String Theory


  We review some applications of Type 0 string theory in the context of the
AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 13670 </DOCNO>
Semiconducting Characteristics of Magnesium-Doped Al2O3 Single Crystals


  DC and AC electrical measurements were performed to investigate the
electrical conductivity of alpha-Al2O3:Mg samples with different concentrations
of [Mg]^0 centers .The concentration of [Mg]^0 centers was monitored by the
opticalabsorption peak at 2.56 eV. At low electrical fields, DC measurements
reveal blocking contacts. Steady electroluminescence is emitted at the negative
electrodeindicating that the majority of carriers are holes. Low voltage AC
measurements show that the equivalent circuit for the sample is the bulk
resistance in series with the junction capacitance connected in parallel with a
capacitance, which represents the dielectric constant of the sample. The values
determined for the bulk resistance in both DC and AC experiments are in good
agreement. The electrical conductivity of Al2O3:Mg crystals increases linearly
with the concentration of [Mg]^0 centers, regardless of the amount of other
impurities also present in the crystals, and is four times higher in the
$c_{\perpendicular}$ than in the $c_{\parallel}$ direction. The conductivity is
thermally activated with an activation energy of 0.68 eV, which is independent
of: 1) the [Mg]^0 content, 2) the crystallographic orientation, and 3) the
concentration of other impurities. These results favor the {\it
small-polaron-motion} mechanism.

</DOC>
<DOC>
<DOCNO> 9391 </DOCNO>
Fermi level quantum numbers and secondary gap of conducting carbon


  For the single-wall carbon nanotubes conducting in the simplest tight binding
model, the complete set of line group symmetry based quantum numbers for the
bands crossing at Fermi level are given. Besides linear (k), helical (k'} and
angular momenta, emerging from roto-translational symmetries, the parities of U
axis and (in the zig-zag and armchair cases only) mirror planes appear in the
assignation. The helical and angular momentum quantum numbers of the crossing
bands never vanishes, what supports proposed chirality of currents. Except for
the armchair tubes, the crossing bands have the same quantum numbers and,
according to the non-crossing rule, a secondary gap arises, as it is shown by
the accurate tight-binding calculation. In the armchair case the different
vertical mirror parity of the crossing bands provides substantial conductivity,
though kF is slightly decreased.

</DOC>
<DOC>
<DOCNO> 39726 </DOCNO>
Search for new Physics in rare B Decays


  A search for the decay B+- to K+-K+-pi-+ was performed using data collected
by the OPAL detector at LEP. These decays are strongly suppressed in the
Standard Model but could occur with a higher branching ratio in supersymmetric
models, especially in those with R-parity violating couplings. No evidence for
a signal was observed and a 90% confidence level upper limit of 1.29x10^-4 was
set for the branching ratio.

</DOC>
<DOC>
<DOCNO> 119321 </DOCNO>
Towards global-phase-delay VLBI astrometry: observations of QSO 1150+812


  On 18 November 1993, we observed the QSO 1150+812 and the BL Lac object
1803+784, nearly 15\deg apart on the sky, with a VLBI array, simultaneously
recording at 8.4 and 2.3 GHz. Using difference astrometry techniques, we
determined the coordinates of 1803+784 relative to those of 1150+812 to be
\Delta\alpha = 6h 7m 33.18469 arcsec +- 0.00020 arcsec \Delta\delta = -2deg 30'
25''.13557 +- 0''.00075 These standard errors contain estimated contributions
from the propagation medium, the effects of source opacity, and the possible
misidentification of the reference point in some of the maps. We obtained
comparably accurate and consistent relative positions of the radio sources with
GPS-based ionosphere corrections, thus demonstrating that dual-frequency
observations are not required for state-of-the-art accuracy in VLBI astrometry.
These results also demonstrate the feasibility of using single-frequency
measurements for sources separated by 15$^\circ$ on the sky, and open the
avenue for the application of this technique on a full-sky scale.

</DOC>
<DOC>
<DOCNO> 68887 </DOCNO>
SARGE: an algorithm for generating QCD-antennas


  We present an algorithm to generate any number of random massless momenta in
phase space, with a distribution that contains the kinematical pole structure
that is typically found in multi-parton QCD-processes. As an application, we
calculate the cross-section of some \eplus\eminus \to partons processes, and
compare SARGE's performance with that of the uniform-phase space generator
RAMBO.

</DOC>
<DOC>
<DOCNO> 11967 </DOCNO>
Writhing Geometry at Finite Temperature: Random Walks and Geometric


  We study the geometry of a semiflexible polymer at finite temperatures. The
writhe can be calculated from the properties of Gaussian random walks on the
sphere. We calculate static and dynamic writhe correlation functions. The
writhe of a polymer is analogous to geometric or Berry phases studied in optics
and wave mechanics. Our results can be applied to confocal microscopy studies
of stiff filaments and to simulations of short DNA loops

</DOC>
<DOC>
<DOCNO> 102259 </DOCNO>
Dynamical Weyl groups and applications


  Following a preceding paper of Tarasov and the second author, we define and
study a new structure, which may be regarded as the dynamical analogue of the
Weyl group for Lie algebras and of the quantum Weyl group for quantized
enveloping algebras. We give some applications of this new structure.

</DOC>
<DOC>
<DOCNO> 12024 </DOCNO>
One-dimensional spinless fermion model with competing interactions


  An accurate numerical consideration of 1D spinless fermion model with
next-nearest neighbour (NNN) interactions is carried out for the electron
concentrations 4/7. It is shown that depending on the parameters of the model
it can be either Luttinger liquid or bipolaron liquid. In the former case
competing interactions can result in a smooth behavior of one-electron
distribution function at the Fermi surface with a divergence in the second
derivative with respect to the quasimomentum (and not in the first one, as
usual). In this connection, uncommon photoemission spectra for some 1D
conductors can be explained qualitatively.

</DOC>
<DOC>
<DOCNO> 170604 </DOCNO>
Quantum algorithms for solvable groups


  In this paper we give a polynomial-time quantum algorithm for computing
orders of solvable groups. Several other problems, such as testing membership
in solvable groups, testing equality of subgroups in a given solvable group,
and testing normality of a subgroup in a given solvable group, reduce to
computing orders of solvable groups and therefore admit polynomial-time quantum
algorithms as well. Our algorithm works in the setting of black-box groups,
wherein none of these problems can be computed classically in polynomial time.
As an important byproduct, our algorithm is able to produce a pure quantum
state that is uniform over the elements in any chosen subgroup of a solvable
group, which yields a natural way to apply existing quantum algorithms to
factor groups of solvable groups.

</DOC>
<DOC>
<DOCNO> 122703 </DOCNO>
Before Inflation


  Observations of the cosmic microwave sky are revealing the primordial
non-uniformities from which all structure in the Universe grew. The only known
physical mechanism for generating the inhomogeneities we see involves the
amplification of quantum fluctuations during a period of inflation. Developing
the theory further will require progress in quantum cosmology, connecting
inflation to a theory of the initial state of the Universe. I discuss recent
work within the framework of the Euclidean no boundary proposal, specifically
classical instanton solutions and the computation of fluctuations around them.
Within this framework, and for a generic inflationary theory, it appears that
an additional anthropic constraint is required to explain the observed
Universe. I outline an attempt to impose such a constraint in a precise
mathematical manner.

</DOC>
<DOC>
<DOCNO> 100687 </DOCNO>
Entropy and mixing for amenable group actions


  For \Gamma a countable amenable group consider those actions of \Gamma as
measure-preserving transformations of a standard probability space, written as
{T_\gamma}_{\gamma \in \Gamma} acting on (X,{\cal F}, \mu). We say
{T_\gamma}_{\gamma\in\Gamma} has completely positive entropy (or simply cpe
for short) if for any finite and nontrivial partition P of X the entropy
h(T,P) is not zero. Our goal is to demonstrate what is well known for actions
of \Bbb Z and even \Bbb Z^d, that actions of completely positive entropy have
very strong mixing properties. Let S_i be a list of finite subsets of \Gamma.
We say the S_i spread if any particular \gamma \neq id belongs to at most
finitely many of the sets S_i S_i^{-1}.
  Theorem 0.1. For {T_\gamma}_{\gamma \in \Gamma} an action of \Gamma of
completely positive entropy and P any finite partition, for any sequence of
finite sets S_i\subseteq \Gamma which spread we have \frac 1{\# S_i}
h(\spans{S_i}{P}){\mathop{\to}_i} h(P).
  The proof uses orbit equivalence theory in an essential way and represents
the first significant application of these methods to classical entropy and
mixing.

</DOC>
<DOC>
<DOCNO> 100812 </DOCNO>
Knots and Contact Geometry


  We classify Legendrian torus knots and figure eight knots in the tight
contact structure on the 3-sphere up to Legendrian isotopy. As a corollary to
this we also obtain the classification of transversal torus knots and figure
eight knots up to transversal isotopy.

</DOC>
<DOC>
<DOCNO> 151190 </DOCNO>
Two-dimensional black holes as open strings: A new realization of the


  We show that weak-coupled two-dimensional dilaton gravity on Anti-de Sitter
space can be described by the dynamics of an open string. Neumann and Dirichlet
boundary conditions for the string lead to two different realizations of the
Anti-de Sitter/Conformal Field Theory correspondence. In particular, in the
Dirichlet case the thermodynamical entropy of two-dimensional black holes can
be exactly reproduced by counting the string states.

</DOC>
<DOC>
<DOCNO> 12678 </DOCNO>
Spin waves in ultrathin ferromagnetic overlayers


  The influence of a non-magnetic metallic substrate on the spin wave
excitations in ultrathin ferromagnetic overlayers is investigated for different
crystalline orientations. We show that spin wave dumping in these systems occur
due to the tunneling of holes from the substrate into the overlayer, and that
the spin wave energies may be considerably affected by the exchange coupling
mediated by the substrate.

</DOC>
<DOC>
<DOCNO> 100129 </DOCNO>
Schubert Calculus and Threshold Polynomials of Affine Fusion


  We show how the threshold level of affine fusion, the fusion of
Wess-Zumino-Witten (WZW) conformal field theories, fits into the Schubert
calculus introduced by Gepner. The Pieri rule can be modified in a simple way
to include the threshold level, so that calculations may be done for all
(non-negative integer) levels at once. With the usual Giambelli formula, the
modified Pieri formula deforms the tensor product coefficients (and the fusion
coefficients) into what we call threshold polynomials. We compare them with the
q-deformed tensor product coefficients and fusion coefficients that are related
to q-deformed weight multiplicities. We also discuss the meaning of the
threshold level in the context of paths on graphs.

</DOC>
<DOC>
<DOCNO> 69293 </DOCNO>
Aspects of QCD, from the Tevatron to the LHC


  This contribution presents a selection of the topics (parton densities,
fixed-order calculations, parton showers, soft-gluon resummation) discussed in
my introductory lectures at the Workshop and includes a pedagogical overview of
the corresponding theoretical tools.

</DOC>
<DOC>
<DOCNO> 8869 </DOCNO>
Marshall-Peierls sign rule in frustrated Heisenberg chains


  We consider the frustrated antiferromagnetic s=1 Heisenberg quantum spin
chain with regard to the Marshall-Peierls sign rule (MPSR). By using exact
diagonalization data we investigate the breakdown of the MPSR in dependence on
frustration and compare our findings with data for s=1/2. We calculate a
critical value of frustration J_2(crit) where the MPSR is violated. The
extrapolation of this value to the infinite chain limit holds J_2(crit) approx.
0.016, lower than in the case of s=1/2 (J_2(crit) approx. 0.027). This points
to a stronger influence of frustration in the case of s=1. Nevertheless the
calculation of the weight of the Ising-states violating the MPSR shows that the
MPSR holds approximately even for quite large frustration and may be used for
numerical techniques.

</DOC>
<DOC>
<DOCNO> 8332 </DOCNO>
Onset of sliding friction in incommensurate systems


  We study the dynamics of an incommensurate chain sliding on a periodic
lattice, modeled by the Frenkel Kontorova hamiltonian with initial kinetic
energy, without damping and driving terms. We show that the onset of friction
at all velocities is due to a novel kind of dissipative parametric resonances,
involving several resonant phonons which are driven by the (dissipationless)
coupling of the center of mass motion to the phonons with wavevector related to
the modulating potential. We establish quantitative estimates for their
existence in finite systems and point out the analogy with the induction
phenomenon in Fermi-Ulam-Pasta lattices.

</DOC>
<DOC>
<DOCNO> 151015 </DOCNO>
The AdS-CFT correspondence, consistent truncations and gauge invariance


  We give arguments for a conjecture made in a previous paper, that one has to
use only the gauged sugra action for the calculation of correlators of certain
operators via the AdS-CFT correspondence. The existence of consistent
truncations implies that the massive modes decouple, and gauged supergravity is
sufficient for computing n-point functions of CFT operators coupled to the
massless (sugra) sector. The action obtained from the linear ansatz, of the
type $\phi(x,y)=\phi_I(x)Y^I(y)$ gives only part of the gauged sugra. This
means that there is a difference for the correlators on the boundary of AdS
space. We find, studying examples of correlators, that the right prescription
is to use the full gauged sugra, which implies using the full nonlinear KK
ansatz. To this purpose, we analyze 3 point functions of various gauge fields
in 5 and 7 dimensions, and the R-current anomaly in the corresponding CFT. We
also show that the nonlinear rotation in the tower of scalar fields of Lee et
al., Corrado et al. and Bastianelli and Zucchini produces a consistent
truncation to the massless level and coincides with the Taylor expansion of the
nonlinear KK ansatz in massless scalar fluctuations. Finally, we speculate
about the way to do the full nonlinear rotation for the massive tower.

</DOC>
<DOC>
<DOCNO> 169833 </DOCNO>
Physical implementation for entanglement purification of Gaussian


  We give a detailed description of the entanglement purification protocol
which generates maximally entangled states with high efficiencies from
realistic Gaussian continuous variable entangled states. The physical
implementation of this protocol is extensively analyzed using high finesse
cavities and cavity enhanced cross Kerr nonlinearities. In particular, we take
into account many imperfections in the experimental scheme and calculate their
influences. Quantitative requirements are given for the relevant experimental
parameters.

</DOC>
<DOC>
<DOCNO> 11045 </DOCNO>
Interactions of several replicas in the random field Ising model


  The replicated field theory of the random field Ising model involves the
couplings of replicas of different indices. The resulting correlation functions
involve a superposition of different types of long distance behaviours. However
the $n=0$ limit allows one to discuss the renormalization group properties in
spite of this phenomenon. The attraction of pairs of replicas is enhanced under
renormalization flow and no stable fixed point is found. Consequently an
instability occurs in the paramagnetic region, before one reaches the Curie
line, signalling the onset of replica symmetry breaking.

</DOC>
<DOC>
<DOCNO> 102349 </DOCNO>
Representations of distributive semilattices in ideal lattices of


  We study the relationships among existing results about representations of
distributive semilattices by ideals in dimension groups, von Neumann regular
rings, C*-algebras, and complemented modular lattices. We prove additional
representation results which exhibit further connections with the scattered
literature on these different topics.

</DOC>
<DOC>
<DOCNO> 13972 </DOCNO>
Extended Ensemble Monte Carlo


  ``Extended Ensemble Monte Carlo''is a generic term that indicates a set of
algorithms which are now popular in a variety of fields in physics and
statistical information processing. Exchange Monte Carlo (Metropolis-Coupled
Chain, Parallel Tempering), Simulated Tempering (Expanded Ensemble Monte
Carlo), and Multicanonical Monte Carlo (Adaptive Umbrella Sampling) are typical
members of this family. Here we give a cross-disciplinary survey of these
algorithms with special emphasis on the great flexibility of the underlying
idea. In Sec.2, we discuss the background of Extended Ensemble Monte Carlo. In
Sec.3, 4 and 5, three types of the algorithms, i.e., Exchange Monte Carlo,
Simulated Tempering, Multicanonical Monte Carlo are introduced. In Sec.6, we
give an introduction to Replica Monte Carlo algorithm by Swendsen and Wang.
Strategies for the construction of special-purpose extended ensembles are
discussed in Sec.7. We stress that an extension is not necessary restricted to
the space of energy or temperature. Even unphysical (unrealizable)
configurations can be included in the ensemble, if the resultant fast mixing of
the Markov chain offsets the increasing cost of the sampling procedure.
Multivariate (multi-component) extensions are also useful in many examples. In
Sec.8, we give a survey on extended ensembles with a state space whose
dimensionality is dynamically varying. In the appendix, we discuss advantages
and disadvantages of three types of extended ensemble algorithms.

</DOC>
<DOC>
<DOCNO> 169794 </DOCNO>
All Teleportation and Dense Coding Schemes


  We establish a one-to-one correspondence between (1) quantum teleportation
schemes, (2) dense coding schemes, (3) orthonormal bases of maximally entangled
vectors, (4) orthonormal bases of unitary operators with respect to the
Hilbert-Schmidt scalar product, and (5) depolarizing operations, whose Kraus
operators can be chosen to be unitary. The teleportation and dense coding
schemes are assumed to be ``tight'' in the sense that all Hilbert spaces
involved have the same finite dimension d, and the classical channel involved
distinguishes d^2 signals. A general construction procedure for orthonormal
bases of unitaries, involving Latin Squares and complex Hadamard Matrices is
also presented.

</DOC>
<DOC>
<DOCNO> 102128 </DOCNO>
Scattering theory for conformally compact metrics with variable


  We develop the scattering theory of general conformally compact metrics. For
low frequencies, the domain of the scattering matrix is shown to be frequency
dependent. In particular, generalized eigenfunctions exhibit L^2 decay in
directions where the asymptotic curvature is sufficiently negative. The
scattering matrix is shown to be a pseudodifferential operator. For generic
frequency in this part of the continuous spectrum, we give an explicit
construction of the resolvent kernel.

</DOC>
<DOC>
<DOCNO> 68884 </DOCNO>
Enhanced antiproton production in Pb(160 AGeV)+Pb reactions: evidence


  The centrality dependence of the antiproton per participant ratio is studied
in Pb(160 AGeV)+Pb reactions. Antiproton production in collisions of heavy
nuclei at the CERN/SPS seems considerably enhanced as compared to conventional
hadronic physics, given by the antiproton production rates in $pp$ and
antiproton annihilation in $\bar{p}p$ reactions. This enhancement is consistent
with the observation of strong in-medium effects in other hadronic observables
and may be an indication of partial restoration of chiral symmetry.

</DOC>
<DOC>
<DOCNO> 13691 </DOCNO>
Force Dependence of the Michaelis Constant in a Two-State Ratchet Model


  We present a quantitative analysis of recent data on the kinetics of ATP
hydrolysis, which has presented a puzzle regarding the load dependence of the
Michaelis constant. Within the framework of coarse grained two-state ratchet
models, our analysis not only explains the puzzling data, but provides a
modified Michaelis law, which could be useful as a guide for future
experiments.

</DOC>
<DOC>
<DOCNO> 99341 </DOCNO>
Stability of the solution to inverse obstacle scattering problem


  It is proved that if the scattering amplitudes at a fixed wavenumber for two
obstacles from a certain large class of obstacles differ a little, than the
obstacles differ a little. Error estimate is given. It is proved that there is
an inversion formula for finding the obstacle from a fixed-energy scattering
data.

</DOC>
<DOC>
<DOCNO> 170467 </DOCNO>
On The Biphoton Wavelength


  We report on an experiment showing that the wavelength of a biphoton is
clearly dependent on the measurement scheme and on the way it is defined. It is
shown that it can take any value, depending on the control of the
interferometer phase differences. It is possible to identify the interference
of the single and two-photon wavepackets as particular cases of the most
general interference process. The variable wavelength has no implication on the
energy of the individual photons neither on the total energy of the biphoton.

</DOC>
<DOC>
<DOCNO> 68429 </DOCNO>
Superheavy Majorana neutrino effects in the lepton-number violating e- +


  In the minimal extension of the standard electroweak theory with ultra
massive Majorana neutrinos, the process e- + e- -> mu- + mu- could be
observable, in sharp contrast with the reaction e- + e- -> W- + W- which is
entirely controlled by neutrinoless double beta decay $\beta \beta_{0 \nu}$
data. Our result provides the process background that must be confronted "new
physics" models which postulate doubly charged particles, such as the gauge
bilepton Y^{-} in the $SU(3)_{\rm c} \times SU(3)_{\rm L} \times U(1)$ model,
the left-right $SU(2)_{\rm L} \times SU(2)_{\rm R} \times U(1)_{\rm B-L}$ one,
and its supersymmetric version with doubly charged Higgs multiplets.

</DOC>
<DOC>
<DOCNO> 68847 </DOCNO>
NLO corrections to the BFKL equation in QCD and in supersymmetric gauge


  We study next-to-leading corrections to the integral kernel of the BFKL
equation for high energy cross-sections in QCD and in supersymmetric gauge
theories. The eigenvalue of the BFKL kernel is calculated in an analytic form
as a function of the anomalous dimension \gamma of the local gauge-invariant
operators and their conformal spin n. For the case of an extended N=4 SUSY the
kernel is significantly simplified. In particular, the terms non-analytic in n
are canceled. We discuss the relation between the DGLAP and BFKL equations in
the N=4 model.

</DOC>
<DOC>
<DOCNO> 120137 </DOCNO>
Bayesian Methods for Cosmological Parameter Estimation from Cosmic


  We present a strategy for a statistically rigorous Bayesian approach to the
problem of determining cosmological parameters from the results of observations
of anisotropies in the cosmic microwave radiation background. We propose the
application of Markov chain Monte Carlo methods, specifically the
Metropolis-Hastings algorithm, to estimate the parameters. A complete
statistical analysis is presented, with the Metropolis-Hastings algorithm
described in detail.

</DOC>
<DOC>
<DOCNO> 39705 </DOCNO>
Simulation of UHE muons propagation for GEANT3


  A simulation package for the transport of high energy muons has been
developed. It has been conceived to replace the muon propagation software
modules implemented in the detector simulation program GEANT3. Here we discuss
the results achieved with our package and we check the agreement with numerical
calculations up to 10**8 GeV.

</DOC>
<DOC>
<DOCNO> 9656 </DOCNO>
Possible Localized Modes in the Uniform Quantum Heisenberg Chains of


  A model of mobile-bond defects is tentatively proposed to analyze the
"anomalies" observed on the NMR spectrum of the quantum Heisenberg chains of
Sr2CuO3. A bond-defect is a local change in the exchange coupling. It results
in a local alternating magnetization (LAM), which when the defect moves,
creates a flipping process of the local field seen by each nuclear spin. At low
temperature, when the overlap of the LAM becomes large, the defects form a
periodic structure, which extends over almost all the chains. In that regime,
the density of bond-defects decreases linearly with T.

</DOC>
<DOC>
<DOCNO> 12995 </DOCNO>
Lattice Resistance and Peierls Stress in Finite-size Atomistic


  Atomistic computations of the Peierls stress in fcc metals are relatively
scarce. By way of contrast, there are many more atomistic computations for bcc
metals, as well as mixed discrete-continuum computations of the Peierls-Nabarro
type for fcc metals. One of the reasons for this is the low Peierls stresses in
fcc metals. Because atomistic computations of the Peierls stress take place in
finite simulation cells, image forces caused by boundaries must either be
relaxed or corrected for if system size independent results are to be obtained.
One of the approaches that has been developed for treating such boundary forces
is by computing them directly and subsequently subtracting their effects, as
developed by V. B. Shenoy and R. Phillips [Phil. Mag. A, 76 (1997) 367]. That
work was primarily analytic, and limited to screw dislocations and special
symmetric geometries. We extend that work to edge and mixed dislocations, and
to arbitrary two-dimensional geometries, through a numerical finite element
computation. We also describe a method for estimating the boundary forces
directly on the basis of atomistic calculations. We apply these methods to the
numerical measurement of the Peierls stress and lattice resistance curves for a
model aluminum (fcc) system using an embedded-atom potential.

</DOC>
<DOC>
<DOCNO> 9187 </DOCNO>
Two Kinds of the Coexistent States in One-Dimensional Quarter -Filled


  The coexistent state of the spin density wave (SDW) and the charge density
wave (CDW) in the one-dimensional quarter-filled system and with the Coulomb
interaction up to the next-nearest sites under magnetic fields is studied. It
is found that, in the coexistent state of $2k_{\rm F}$-SDW and $2k_{\rm
F}$-CDW, the charge order is suppressed and $2k_{\rm F}$-SDW changes to
$2k_{\rm F}$-SDW having the different alignment of spin under high magnetic
fields, whereas, in the coexistent state of $2k_{\rm F}$-SDW and $4k_{\rm
F}$-CDW, $4k_{\rm F}$-CDW still remains and $2k_{\rm F}$-SDW is suppressed. The
critical temperature of the charge order is higher than that of the spin order
when the inter-site Coulomb interaction is strong. These will be observed in
experiments such as the X-ray scattering measurement and NMR.

</DOC>
<DOC>
<DOCNO> 71745 </DOCNO>
Elastic $\nu e^-$ scattering of solar neutrinos with electromagnetic


  We consider the azimuthal asymmetry of the recoil electrons in elastic $\nu
e^-$ scattering of solar neutrinos, which can arise if neutrinos have
electromagnetic moments and there is a large solar magnetic field. We show that
using this effect it is not possible to distinguish between magnetic and
electric dipole moment in the 1-Dirac and 2-Majorana neutrino cases and that
averaging over neutrino energy is important and suppresses the azimuthal
asymmetry in the 2-Majorana case.

</DOC>
<DOC>
<DOCNO> 99838 </DOCNO>
Logarithmic Kodaira-Akizuki-Nakano vanishing and Arakelov-Parshin


  The article has two parts. The first part is devoted to proving a singular
version of the logarithmic Kodaira-Akizuki-Nakano vanishing theorem of Esnault
and Viehweg. This is then used to prove other vanishing theorems. In the second
part these vanishing theorems are used to prove an Arakelov-Parshin type
boundedness result for families of canonically polarized varieties with
rational Gorenstein singularities.

</DOC>
<DOC>
<DOCNO> 9972 </DOCNO>
Condensate fluctuations in finite Bose-Einstein condensates at finite


  A Langevin equation for the complex amplitude of a single-mode Bose-Einstein
condensate is derived. The equation is first formulated phenomenologically,
defining three transport parameters. It is then also derived microscopically.
Expressions for the transport parameters in the form of Green-Kubo formulas are
thereby derived and evaluated for simple trap geometries, a cubic box with
cyclic boundary conditions and an isotropic parabolic trap. The number
fluctuations in the condensate, their correlation time, and the
temperature-dependent collapse-time of the order parameter as well as its
phase-diffusion coefficient are calculated.

</DOC>
<DOC>
<DOCNO> 85101 </DOCNO>
On the stability of the Kerr metric


  The reduced (in the angular coordinate $\phi$) wave equation and Klein-Gordon
equation are considered on a Kerr background and in the framework of
$C^{0}$-semigroup theory. Each equation is shown to have a well-posed initial
value problem,i.e., to have a unique solution depending continuously on the
data. Further, it is shown that the spectrum of the semigroup's generator
coincides with the spectrum of an operator polynomial whose coefficients can be
read off from the equation. In this way the problem of deciding stability is
reduced to a spectral problem and a mathematical basis is provided for mode
considerations. For the wave equation it is shown that the resolvent of the
semigroup's generator and the corresponding Green's functions can be computed
using spheroidal functions. It is to be expected that, analogous to the case of
a Schwarzschild background, the quasinormal frequencies of the Kerr black hole
appear as {\it resonances}, i.e., poles of the analytic continuation of this
resolvent. Finally, stability of the background with respect to reduced massive
perturbations is proven for large enough masses.

</DOC>
<DOC>
<DOCNO> 10552 </DOCNO>
Real-Space Mesh Techniques in Density Functional Theory


  This review discusses progress in efficient solvers which have as their
foundation a representation in real space, either through finite-difference or
finite-element formulations. The relationship of real-space approaches to
linear-scaling electrostatics and electronic structure methods is first
discussed. Then the basic aspects of real-space representations are presented.
Multigrid techniques for solving the discretized problems are covered; these
numerical schemes allow for highly efficient solution of the grid-based
equations. Applications to problems in electrostatics are discussed, in
particular numerical solutions of Poisson and Poisson-Boltzmann equations.
Next, methods for solving self-consistent eigenvalue problems in real space are
presented; these techniques have been extensively applied to solutions of the
Hartree-Fock and Kohn-Sham equations of electronic structure, and to eigenvalue
problems arising in semiconductor and polymer physics. Finally, real-space
methods have found recent application in computations of optical response and
excited states in time-dependent density functional theory, and these
computational developments are summarized. Multiscale solvers are competitive
with the most efficient available plane-wave techniques in terms of the number
of self-consistency steps required to reach the ground state, and they require
less work in each self-consistency update on a uniform grid. Besides excellent
efficiencies, the decided advantages of the real-space multiscale approach are
1) the near-locality of each function update, 2) the ability to handle global
eigenfunction constraints and potential updates on coarse levels, and 3) the
ability to incorporate adaptive local mesh refinements without loss of optimal
multigrid efficiencies.

</DOC>
<DOC>
<DOCNO> 10514 </DOCNO>
Dynamical chaos and power spectra in toy models of heteropolymers and


  The dynamical chaos in Lennard-Jones toy models of heteropolymers is studied
by molecular dynamics simulations. It is shown that two nearby trajectories
quickly diverge from each other if the heteropolymer corresponds to a random
sequence. For good folders, on the other hand, two nearby trajectories may
initially move apart but eventually they come together. Thus good folders are
intrinsically non-chaotic. A choice of a distance of the initial conformation
from the native state affects the way in which a separation between the twin
trajectories behaves in time. This observation allows one to determine the size
of a folding funnel in good folders. We study the energy landscapes of the toy
models by determining the power spectra and fractal characteristics of the
dependence of the potential energy on time. For good folders, folding and
unfolding trajectories have distinctly different correlated behaviors at low
frequencies.

</DOC>
<DOC>
<DOCNO> 117164 </DOCNO>
Progress in the Next Linear Collider Design


  An electron/positron linear collider with a center-of-mass energy between 0.5
and 1 TeV would be an important complement to the physics program of the LHC in
the next decade. The Next Linear Collider (NLC) is being designed by a US
collaboration (FNAL, LBNL, LLNL, and SLAC) which is working closely with the
Japanese collaboration that is designing the Japanese Linear Collider (JLC).
The NLC main linacs are based on normal conducting 11 GHz rf. This paper will
discuss the technical difficulties encountered as well as the many changes that
have been made to the NLC design over the last year. These changes include
improvements to the X-band rf system as well as modifications to the injector
and the beam delivery system. They are based on new conceptual solutions as
well as results from the R&D programs which have exceeded initial
specifications. The net effect has been to reduce the length of the collider
from about 32 km to 25 km and to reduce the number of klystrons and modulators
by a factor of two. Together these lead to significant cost savings.

</DOC>
<DOC>
<DOCNO> 39952 </DOCNO>
Top Quark Mass Measurements at the Tevatron


  The general strategy, as well as channel-specific details, applied to the
measurement of the top quark mass at the Tevatron in Run I are reviewed, and
the combination of the results obtained by the CDF and DO collaborations
presented. The accelerator and detector upgrades for Run II are described, and
expected improvements in the systematic uncertainties on the measurement
evaluated.

</DOC>
<DOC>
<DOCNO> 122849 </DOCNO>
Reddenings and metallicities in the LMC and SMC from Stroemgren CCD


  The individual reddenings for B stars in two fields in the Small Magellanic
Cloud (SMC) and two fields in the Large Magellanic Cloud (LMC) are determined
by means of Stroemgren uvby CCD photometry. In both LMC fields we find a
foreground reddening of E(B-V) = 0.085 +/- 0.02, and for the SMC fields we find
E(B-V) = 0.070 +/- 0.02. In addition to the foreground reddening we find
contributions from reddening intrinsically in the Clouds up to E(B-V) ~ 0.21.
The intrinsic contribution is not correlated with position within our 6 x 4.5
arcmin CCD fields but varies in an essentially random way. Unless the reddening
is measured for a particular object, it will be uncertain by +/- 0.035 in
E(B-V) (best case, far from the central bars) to more than +/- 0.10 (close to
the central bars).
  The Stroemgren vby photometry has been used to derive metallicities for GK
giant stars in the observed fields. Adopting average reddenings we obtain mean
metallicities which are consistent with those found from spectroscopic studies
of F and G supergiants but with a considerable scatter, from [Fe/H]~ -2.0 to >
0. A significant fraction of the scatter is, however, due to reddening
variations rather than being intrinsic. The possible existence of high
metallicity stars should be investigated further using spectroscopic methods.

</DOC>
<DOC>
<DOCNO> 11968 </DOCNO>
Strengthening of a Polymer Interface: Interdiffusion and Crosslinking


  In many industrial processes, pieces of the same polymer material are brought
into contact at a temperature above the glass transition. Interdiffusion then
takes place across the interface and leads to a strengthening of the junction.
Often, a crosslinker agent is also added in order to improve the global
mechanical properties of the material, as in the formation of latex films from
dispersed solutions of polymer particles. In these systems, the interdiffusion
process and the crosslinking reaction couple strongly, and, in practice, may
sometimes interfere in a way that proves unfavorable to the tenacity of the
film. We studied theoretically the competition between interdiffusion and
crosslinking, and found a control parameter tuning the balance between these
two processes, in terms of simple physical quantities. The case of practical
interest occurs when this parameter is much smaller than unity: the reaction
locks the interfacial chains once a significant mixing has developed, resulting
in films with good mechanical properties.

</DOC>
<DOC>
<DOCNO> 68376 </DOCNO>
rho_T Production via W_L Z_L Fusion at Hadronic Colliders


  Multiscale technicolor models predict the existence of high mass resonances
at hadron colliders. Although the quark fusion process of production dominates,
vector boson fusion offers the advantage of allowing forward jet tagging for
background suppression. We calculate here the cross section and differential
distributions for $\rho_T$ production in the vector boson fusion channel at the
LHC.

</DOC>
<DOC>
<DOCNO> 152264 </DOCNO>
Non-perturbative Fermion Propagator for the Massless Quenched QED3


  For massless quenched QED in three dimensions, we evaluate a non-perturbative
expression for the fermion propagator which agrees with its two loop
perturbative expansion in the weak coupling regime. This calculation is carried
out by making use of the Landau-Khalatnikov-Fradkin transformations. Any
improved construction of the fermion-boson vertex must make sure that the
solution of the Schwinger-Dyson equation for the fermion propagator reproduces
this result. For two different gauges, we plot the fermion propagator against
momentum. We then make a comparison with a similar plot, using the earlier
expression for the fermion propagator, which takes into account only the one
loop result.

</DOC>
<DOC>
<DOCNO> 116838 </DOCNO>
Experimental Determination of the Characteristics of a Positron Source


  Numerical simulations and `proof of principle' experiments showed clearly the
interest of using crystals as photon generators dedicated to intense positron
sources for linear colliders. An experimental investigation, using a 10 GeV
secondary electron beam, of the SPS-CERN, impinging on an axially oriented
thick tungsten crystal, has been prepared and operated between May and August
2000. After a short recall on the main features of positron sources using
channeling in oriented crystals, the experimental set-up is described. A
particular emphasis is put on the positron detector made of a drift chamber,
partially immersed in a magnetic field. The enhancement in photon and positron
production in the aligned crystal have been observed in the energy range 5 to
40 GeV, for the incident electrons, in crystals of 4 and 8 mm as in an hybrid
target. The first results concerning this experiment are presented hereafter.

</DOC>
<DOC>
<DOCNO> 121061 </DOCNO>
The state of two neutrinos moving in the opposite directions


  It is considered the flux of neutrinos moving from the source in the opposite
directions. The state of two neutrinos moving in the opposite directions is a
superposition of the state $|\psi_{12}>$ and the state $|\psi_{21}>$ in which
the positions of neutrinos are interchanged. Neutrinos in the state
$|\psi_{21}>$ are P-transformed with respect to neutrinos in the state
$|\psi_{12}>$ therefore if one detects neutrinos in the state $|\psi_{12}>$ it
is forbidden to detect neutrinos in the state $|\psi_{21}>$. Under detection
the number of neutrinos decreases two times, and the energy of neutrinos
increases two times. Hence one can detect only one half of the solar neutrino
flux predicted by the SSM that may provide a solution for the solar neutrino
puzzle.

</DOC>
<DOC>
<DOCNO> 71075 </DOCNO>
Supernovae Ia, evolution and quintessence


  Quintessence models with a dark energy generated by pseudo Nambu-Goldstone
bosons provide a natural framework in which to test the possibility that type
Ia supernovae luminosity distance measurements are at least partially due to an
evolution of the sources, since these models can have parameter values for
which the expansion of the Universe is decelerating as well as values for which
it is accelerating, while being spatially flat in all cases and allowing for a
low density of clumped matter. The results of a recent investigation
(astro-ph/0004138) of current observational bounds which allow for SNe Ia
source evolution are discussed. It is found that models with source evolution
still favour cosmologies with an appreciable amount of acceleration in the
recent past, but that the region of parameter space which is most favoured
shifts significantly.

</DOC>
<DOC>
<DOCNO> 116634 </DOCNO>
A path-integral approach to the collisionless Boltzmann gas


  On contrary to the customary thought, the well-known ``lemma'' that the
distribution function of a collisionless Boltzmann gas keeps invariant along a
molecule's path represents not the strength but the weakness of the standard
theory. One of its consequences states that the velocity distribution at any
point is a condensed ``image'' of all, complex and even discontinuous,
structures of the entire spatial space. Admitting the inability to describe the
entire space with a microscopic quantity, this paper introduces a new type of
distribution function, called the solid-angle-average distribution function.
With help of the new distribution function, the dynamical behavior of
collisionless Boltzmann gas is formulated in terms of a set of integrals
defined by molecular paths. In the new formalism, not only that the
difficulties associated with the standard theory are surmounted but also that
some of practical gases become calculable in terms of today's computer.

</DOC>
<DOC>
<DOCNO> 9085 </DOCNO>
Paramagnetic Reentrance Effect in NS Proximity Cylinders


  A scenario for the unusual paramagnetic reentrance behavior at ultra-low
temperatures in Nb-Ag, Nb-Au, and Nb-Cu cylinders is presented. For the
diamagnetic response down to temperatures of the order 15 mK, the standard
theory (quasi-classical approximation) for superconductors appears to work very
well, assuming that Ag, Au, and Cu remain in the normal state except for the
proximity-induced superconductivity. Here it is proposed that these noble
metals may become p-wave superconductors with a transition temperature of order
10 mK. Below this temperature, p-wave triplet superconductivity emerges around
the periphery of the cylinder. The diamagnetic current flowing in the periphery
is compensated by a quantized paramagnetic current in the opposite direction,
thus providing a simple explanation for the observed increase in the
susceptibility at ultra-low temperatures.

</DOC>
<DOC>
<DOCNO> 99919 </DOCNO>
The projections of n-knots which are not the projection of any unknotted


  Let n be any integer greater than two. We prove that there exists a
projection P having the following properties. (1) P is not the projection of
any unknotted knot. (2) The singular point set of P consists of double points.
(3) P is the projection of an n-knot which is diffeomorphic to the standard
sphere.
  We prove there exists an immersed n-sphere (in R^{n+1}\times{0}) which is not
the projection of any n-knot (n>2). Note that the second theorem is different
from the first one.

</DOC>
<DOC>
<DOCNO> 121165 </DOCNO>
Kinematic Evidence of Minor Mergers in Normal Sa Galaxies


  A detailed study of nearby, morphologically normal Sa galaxies reveals that
about half show some spectrocopic evidence for kinematically distinct
components despite their undisturbed optical appearance. In eight of nine
objects mapped in the 21 cm HI line, the HI distribution extends far outside
the optical disk and warps of the HI disk are complex. The multiwavelength
evidence can be interpreted in terms of the kinematic "memory" of past minor
mergers in objects that otherwise exhibit no morphological signs of
interaction.

</DOC>
<DOC>
<DOCNO> 11555 </DOCNO>
Metastability and the Casimir Effect in Micromechanical Systems


  Electrostatic and Casimir interactions limit the range of positional
stability of electrostatically-actuated or capacitively-coupled mechanical
devices. We investigate this range experimentally for a generic system
consisting of a doubly-clamped Au suspended beam, capacitively-coupled to an
adjacent stationary electrode. The mechanical properties of the beam, both in
the linear and nonlinear regimes, are monitored as the attractive forces are
increased to the point of instability. There "pull-in" occurs, resulting in
permanent adhesion between the electrodes. We investigate, experimentally and
theoretically, the position-dependent lifetimes of the free state (existing
prior to pull-in). We find that the data cannot be accounted for by simple
theory; the discrepancy may be reflective of internal structural instabilities
within the metal electrodes.

</DOC>
<DOC>
<DOCNO> 100107 </DOCNO>
A derivation of Witten's conjecture relating Donaldson and


  We generalize Witten's conjectured formula relating Donaldson and
Seiberg-Witten invariants to manifolds of non-simple type, via equivariant
localization techniques. This approach does not use the theory of non-abelian
monopoles, but works directly on the Donaldson-Witten and Seiberg-Witten moduli
spaces. We give a formal derivation of Witten's conjecture and its
generalization, making use of an infinite dimensional version of the abelian
localization theorem.

</DOC>
<DOC>
<DOCNO> 9731 </DOCNO>
Critical behaviors of the one dimensional Hubbard model with alternating


  We study the critical behaviors of charge and spin excitations in the
one-dimensional Hubbard model with an alternating potential using the density
matrix renormalization group method. Fixing the staggered potential, we find
that there are two critical points separating the band and Mott gap phases. At
the first critical point, the charge-neutral spin-singlet exciton energy gap
vanishes. At the second critical point, both the charge and spin excitation
gaps become critical. Between these two critical points, the ground state is
dimerized.

</DOC>
<DOC>
<DOCNO> 39664 </DOCNO>
Drell-Yan proton-deuteron asymmetry and polarized light-antiquark


  We discuss the Drell-Yan proton-deuteron (p-d) asymmetry R_{pd}, which is
defined by the proton-proton and proton-deuteron cross-section ratio
\Delta_{(T)}\sigma^{pd}/2\Delta_{(T)}\sigma^{pp}, and its relation to the
polarized light-antiquark flavor asymmetry. Using a formalism of the polarized
{\it pd} Drell-Yan process, we show that the R_{pd} especially in the large-x_F
region is very useful for finding the flavor asymmetry in the
longitudinally-polarized and transversity distributions. Our results are
particularly important to study the flavor asymmetry in the transversity
distributions because they cannot be measured by inclusive deep inelastic
scattering and W-production process.

</DOC>
<DOC>
<DOCNO> 71416 </DOCNO>
Deducing the Source of Ultrahigh Energy Cosmic Rays


  The apparent lack of suitable astrophysical sources for cosmic rays with E >
10^{19.7} eV (UHECRs) is the "GZK Paradox". We argue that whatever mechanism
produces them must also account for events down to ~10^{18.7} eV, including
their isotropy and spectral smoothness. This rules out galactic sources,
distributed sources such as topological defects, and Gamma Ray Bursts (GRBs).
We are lead to identify the powerful radio galaxy Cen A, at 3.4 Mpc, as the
probable source of most UHECRs observed at Earth today, and to estimate the
extragalactic magnetic field to be ~0.3 microG.

</DOC>
<DOC>
<DOCNO> 150944 </DOCNO>
Confinement in a Model with Condensate of the Scalar Field


  The idea of ``soft'' confinement when the lifetime of hadron with respect to
quark-gluon channel of decay is greater or at least of the order of some
characteristic time for our Universe is considered. Within the framework of a
model of three nonlinearly interacting fields the explicit form of an effective
potential is found. It provides the confinement of a massive particle within
the limited region of space by means of constant component of the potential
which arises as a result of reorganization of vacuum of one of the scalar
fields. It is shown that the lifetime of hadron being equal to the age of the
Universe leads to the Higgs boson with the mass m > 63.7 GeV and realistic
self-constant.

</DOC>
<DOC>
<DOCNO> 84258 </DOCNO>
Weinberg's energy-momentum pseudotensor for Schwarzschild field


  Weinberg's energy-momentum pseudotensor is obtained for Schwarzschild metric
in harmonic coordinates. On the horizon it possesses unintegrable
singularities. For this reason the total energy of a collapsar can't be
obtained by integrating energy density over the system's volume. The
implication for gravity theories is noted. A thought on how to choose unique
energy-momentum tensor is given.

</DOC>
<DOC>
<DOCNO> 116400 </DOCNO>
Atomic data from the Iron Project.XLIV. Transition probabilities and


  Relativistic atomic structure calculations for electric dipole E1, electric
quadrupole E2 and magnetic dipole M1 transition probabilities among the first
80 fine-structure levels of Fe VI, dominated by configurations 3d^3, 3d^24s,
and 3d^24p, are carried out using the Breit-Pauli version of the code
Superstructure. Experimental energies are used to improve the accuracy of these
transition probabilities. Employing the 80-level collision-radiative (CR) model
with these dipole and forbidden transition probabilities, and Iron Project
R-matrix collisional data, we present a number of [Fe VI] line ratios
applicable to spectral diagnostics of photoionized H II regions. It is shown
that continuum fluorescent excitation needs to be considered in CR models in
order to interpret the observed line ratios of optical [Fe VI] lines in
planetary nebulae NGC 6741, IC 351, and NGC 7662. The analysis leads to
parametrization of line ratios as function of, and as constraints on, the
electron density and temperature, as well as the effective radiation
temperature of the central source and a geometrical dilution factor. The
spectral diagnostics may also help ascertain observational uncertainties. The
method may be generally applicable to other objects with intensive background
radiation fields, such as novae and active galactic nuclei. The extensive new
Iron Project radiative and collisional calculations enable a consistent
analysis of many line ratios for the complex iron ions.

</DOC>
<DOC>
<DOCNO> 117521 </DOCNO>
Stellar-Dynamics of Young Star Clusters


  The stellar-dynamical evolution of bound star clusters during the first few
Myr is dominated by binary-binary and binary-star interactions, the rapid
sinking of the most massive stars to the centre of the clusters and mass loss
from evolving stars. The consequences of these processes for the binary and
stellar population in clusters, and for the star clusters as a whole, are
studied by following the evolution over 150 Myr of a library of compact cluster
models containing up to 10^4 stars.

</DOC>
<DOC>
<DOCNO> 68874 </DOCNO>
Thermalization After Inflation and Reheating Temperature


  We present a detailed examination of thermalization after inflation for
perturbative inflaton decay. Different interactions among particles in the
plasma of inflaton decay products are considered and it will be shown that 2 ->
2 scatterings and particle decay are the important ones. We show that
thermalization occurs after decays dominate scatterings, and that depending on
the typical mass scale of inflaton decay products, different situations may
arise. In particular, thermalization may be delayed until late times, in which
case the bounds from thermal gravitino production on supersymmetric models of
inflation are considerably relaxed. We will also consider the case where the
observable sector consists only of the MSSM matter content, and point out that
flat directions with large vevs may result in earlier thermalization of the
plasma and push the reheat temperature towards its upper limit.

</DOC>
<DOC>
<DOCNO> 99330 </DOCNO>
Hyphs and the Ashtekar-Lewandowski Measure


  Properties of the space $\Ab$ of generalized connections in the Ashtekar
framework are investigated.
  First a construction method for new connections is given. The new parallel
transports differ from the original ones only along paths that pass an initial
segment of a fixed path. This is closely related to a new notion of path
independence. Although we do not restrict ourselves to the immersive smooth or
analytical case, any finite set of paths depends on a finite set of independent
paths, a so-called hyph. This generalizes the well-known directedness of the
set of smooth webs and that of analytical graphs, respectively.
  Due to these propositions, on the one hand, the projections from $\Ab$ to the
lattice gauge theory are surjective and open. On the other hand, an induced
Haar measure can be defined for every compact structure group irrespective of
the used smoothness category for the paths.

</DOC>
<DOC>
<DOCNO> 68791 </DOCNO>
Using the value of beta to help determine gamma from B decays


  It has been pointed out by Gronau and Rosner that the angle gamma of the
unitarity triangle could be determined by combining future results on B_s and
B_d decays to K pi. Here we show that it is important to include in the
analysis the information on the phase beta which will be determined in the near
future. Omitting this information could lead to an error as large as 8 degrees
in gamma.

</DOC>
<DOC>
<DOCNO> 100336 </DOCNO>
G-bundles on Abelian surfaces, hyperkahler manifolds, and stringy Hodge


  We study the moduli space M(G,A) of flat G-bundles on an Abelian surface A,
where G is a compact, simple, simply connected, connected Lie group.
Equivalently, M(G,A) is the (coarse) moduli space of s-equivalence classes of
holomorphic semi-stable G_C-bundles with trivial Chern classes where G_C is the
complexified group.
  M(G,A) has the structure of a hyperkahler orbifold. We show that when G is
Sp(n) or SU(n), M(G,A) has a natural hyperkahler desingularization which we
exhibit as a moduli space of G_C-bundles with an altered stability condition.
In this way, we obtain the two known families of hyperkahler manifolds, the
Hilbert scheme of points on a K3 surface and the generalized Kummer varieties.
We show that for G not Sp(n) or SU(n), the moduli space M(G,A) does not admit a
hyperkahler resolution, in fact, it does not have a crepant resolution.
  Inspired by the physicists Vafa and Zaslow, Batyrev and Dais define ``stringy
Hodge numbers'' for certain orbifolds. These numbers are conjectured to agree
with the Hodge numbers of a crepant resolution (when it exists). We compute the
stringy Hodge numbers of M(SU(n),A) and M(Sp(n),A) and verify the conjecture in
these cases.

</DOC>
<DOC>
<DOCNO> 102133 </DOCNO>
The Bennequin number of n-trivial closed n-braids is negative


  A famous result of Bennequin states that for any braid representative of the
unknot the Bennequin number is negative. We will extend this result to all
n-trivial closed n-braids. This is a class of infinitely many knots closed
under taking mirror images. Our proof relies on a non-standard parametrization
of the Homfly polynomial.

</DOC>
<DOC>
<DOCNO> 99807 </DOCNO>
The Periodic Response of Periodically Perturbated Stochastic Systems


  The paper introduces a new numerical characteristic of one dimensional
stochastic systems. This quantity is a measure of minimal periodicity, can be
detected in the process deep differential structure. The claim is that this new
measure of stochasticity is also a well adapted characteristic for research of
stochastic resonance phenomena.

</DOC>
<DOC>
<DOCNO> 119825 </DOCNO>
General considerations on the illumination of galactic nebulae


  The interpretation of observations over different wavelength domains, which
now exist over a large fraction of the sky, will be used to determine
relationships between a nebula and its' illuminating source.
  The illuminating source of a high latitude nebula must be behind the cloud
and e.g. at close angular distance. It is either a point source behind the
nebula or the average radiation field created by all the background stars. In
the latter case it is possible to estimate the maximum surface brightness a
nebula can reach. Illumination by the galactic plane is always negligible in up
to date observations.
  The red color of some nebulae, when they are not HII regions, is more likely
to be due to large column densities than to an emission process.
  Concerning interstellar grain properties, the same data will be used to
support the well known property that grains scatter starlight in forward
direction.

</DOC>
<DOC>
<DOCNO> 8890 </DOCNO>
A new approach to the ground state of quantum-Hall systems


  I present variational solutions of the many-body Schr\"odinger equation for a
two-dimensional electron system in strong magnetic fields, which have, at
$\nu=1$, the energy about 46% lower than the energy of the Laughlin liquid. At
$\nu=2/3$, I obtain the energy, about 29% lower than was reported so far.

</DOC>
<DOC>
<DOCNO> 118856 </DOCNO>
The Mass of the Andromeda Galaxy


  This paper argues that the Milky Way galaxy is probably the largest member of
the Local Group. The evidence comes from estimates of the total mass of the
Andromeda galaxy (M31) derived from the three dimensional positions and radial
velocities of its satellite galaxies, as well as the projected positions and
radial velocities of its distant globular clusters and planetary nebulae. The
available dataset comprises ten satellite galaxies, seventeen distant globular
clusters and nine halo planetary nebulae with radial velocities. We find the
halo of Andromeda has a mass of about 12 x 10^11 solar masses, together with a
scalelength of roughly 90 kpc and a predominantly isotropic velocity
distribution. For comparison, our earlier estimate for the Milky Way halo is 19
x 10^11 solar masses. Though the error bars are admittedly large, this suggests
that the total mass of M31 is probably less than that of the Milky Way. We
verify the robustness of our results to changes in the modelling assumptions
and to errors caused by the small size and incompleteness of the dataset.
Future prospects using radial velocity surveys of globular clusters and
planetary nebulae, as well as microarcsecond astrometry from the upcoming
satellite missions, are discussed.

</DOC>
<DOC>
<DOCNO> 13822 </DOCNO>
Polarized Neutron Scattering


  The technique of polarized neutron scattering is reviewed with emphasis on
applications. Many examples of the usefulness of the method in various fields
of physics are given like the determination of spin density maps, measurement
of complex magnetic structures with spherical neutron polarimetry, inelastic
neutron scattering and separation of coherent and incoherent scattering with
help of the generalized XYZ method.

</DOC>
<DOC>
<DOCNO> 9815 </DOCNO>
A real-space, rela-time method for the dielectric function


  We present an algorithm to calculate the linear response of periodic systems
in the time-dependent density functional thoery, using a real-space
representation of the electron wave functions and calculating the dynamics in
real time. The real-space formulation increases the efficiency for calculating
the interaction, and the real-time treatment decreases storage requirements and
the allows the entire frequency-dependent response to be calculated at once. We
give as examples the dielectric functions of a simple metal, lithium, and an
elemental insulator, diamond.

</DOC>
<DOC>
<DOCNO> 121053 </DOCNO>
Broad-Band Spectral Energy Distributions of Active Galactic Nuclei from


  We construct a disk-corona model which accounts for the optical-to-X-ray
spectral properties of Seyfert nuclei and QSOs. We study emission spectrum
emerging from a vertical disk-corona structure composed of two-temperature
plasma by solving hydrostatic equilibrium and radiative transfer
self-consistently. A fraction $f$ of viscous heating is assumed to be
dissipated in a corona with a Thomson optical depth of $\tau_c$, where
advective cooling is also included, and a remaining fraction, $1-f$, dissipates
within a main body of the disk. Our model can nicely reproduce the soft X-ray
excess with a power-law shape and the hard tail extending to $\sim$ 50 keV. The
different spectral slopes ($\alpha \sim$ 1.5 below 2keV and $\sim$ 0.5 above,
where $\Fnu \propto \nu^{- \alpha}$) are the results of different emission
mechanisms and different sites; the former slope is due to unsaturated
Comptonization from the innermost zone and the latter is due to a combination
of the Comptonization, bremsstrahlung and a reflection of the coronal radiation
at the disk-corona boundary from the inner to surrounding zone ($\leq$ 300
Schwarzschild radii). The emergent optical spectrum is redder ($\alpha \sim
0.3$) than that of the standard disk ($\alpha \sim -0.3$), being consistent
with observations, due to the different efficiencies of spectral distortion of
disk emission at different radii. Further, we find that the cut-off frequency
of the hard X-ray ($\sim$ coronal electron temperature) and broad-band spectral
shape are insensitive to the black-hole mass, while the peak frequency of the
big blue bump is sensitive to the mass as the peak frequency $\propto
\Mbh^{-1/4}$.

</DOC>
<DOC>
<DOCNO> 117413 </DOCNO>
Constraints on Cosmological Parameters from the Lyman-alpha Forest Power


  We combine COBE-DMR measurements of cosmic microwave background anisotropy
with a recent measurement of the mass power spectrum at redshift z=2.5 from Lya
forest data to derive constraints on cosmological parameters and test the
inflation+CDM scenario of structure formation. By treating the inflationary
spectral index n as a free parameter, we can find successful fits to the COBE
and Lya forest constraints in Omega_m=1 models with and without massive
neutrinos and in low-Omega_m models with and without a cosmological constant.
Within each class of model, the combination of COBE and the Lya forest P(k)
constrains a parameter combination of the form (Omega_m h^a n^b Omega_b^c),
with different indices for each case. This new constraint breaks some of the
degeneracies in cosmological parameter determinations from other measurements.
The Lya forest P(k) provides the first measurement of the slope of the linear
mass power spectrum on ~Mpc scales, and it confirms a basic prediction of the
inflationary CDM scenario: a nearly scale-invariant spectrum of primeval
fluctuations (n~1) that bends towards k^{n-4} on small scales. Considering
additional observational data, we find that COBE-normalized, Omega_m=1 models
that match the Lya forest P(k) do not match the observed masses of rich galaxy
clusters and that a low-Omega_m model with a cosmological constant provides the
best overall fit, even without the direct evidence for cosmic acceleration from
supernovae. Modest improvements in the Lya forest P(k) measurement could
greatly restrict the allowable region of parameter space for CDM models,
constrain the contribution of tensor fluctuations to CMB anisotropy, and
achieve a more stringent test of the current consensus model of structure
formation.

</DOC>
<DOC>
<DOCNO> 39912 </DOCNO>
Noncontact measurement of the tension of a wire


  We present a scheme for noncontact measurement of the tension of a wire, such
as that in a drift chamber or straw tube detector.

</DOC>
<DOC>
<DOCNO> 80901 </DOCNO>
Testing imaginary vs. real chemical potential in finite-temperature QCD


  One suggestion for determining the properties of QCD at finite temperatures
and densities is to carry out lattice simulations with an imaginary chemical
potential whereby no sign problem arises, and to convert the results to real
physical observables only afterwards. We test the practical feasibility of such
an approach for a particular class of physical observables, spatial correlation
lengths in the quark-gluon plasma phase. Simulations with imaginary chemical
potential followed by analytic continuation are compared with simulations with
real chemical potential, which are possible by using a dimensionally reduced
effective action for hot QCD. We find that for imaginary chemical potential the
system undergoes a phase transition at |mu/T| \approx pi/3, and thus
observables are analytic only in a limited range. However, utilising this
range, relevant information can be obtained for the real chemical potential
case.

</DOC>
<DOC>
<DOCNO> 117360 </DOCNO>
O-bearing Molecules in Carbon-rich Proto-Planetary Objects


  We present ISO LWS observations of the proto-planetary nebula CRL 618, a star
evolving very fast to the planetary nebula stage. In addition to the lines of
12CO, 13CO, HCN and HNC, we report on the detection of H2O and OH emission
together with the fine structure lines of [OI] at 63 and 145 um. The abundance
of the latter three species relative to 12CO are 4 10^{-2}, 8 10^{-4} and 4.5
(approximate value) in the regions where they are produced. We suggest that
O-bearing species other than CO are produced in the innermost region of the
circumstellar envelope. The UV photons from the central star photodissociate
most of the molecular species produced in the AGB phase and allow a chemistry
dominated by standard ion-neutral reactions. Not only allow these reactions the
formation of O-bearing species, but they also modify the abundances of C-rich
molecules like HCN and HNC for which we found an abundance ratio of roughly 1,
much lower than in AGB stars. The molecular abundances in the different regions
of the circumstellar envelope have been derived from radiative transfer models
and our knowledge of its physical structure.

</DOC>
<DOC>
<DOCNO> 85270 </DOCNO>
Exact non-singular waves in the anti-de Sitter universe


  A class of radiative solutions of Einstein's field equations with a negative
cosmological constant and a pure radiation is investigated. The space-times,
which generalize the Defrise solution, represent exact gravitational waves
which interact with null matter and propagate in the anti-de Sitter universe.
Interestingly, these solutions have homogeneous and non-singular wave-fronts
for all freely moving observers. We also study properties of sandwich and
impulsive waves which can be constructed in this class of space-times.

</DOC>
<DOC>
<DOCNO> 101017 </DOCNO>
Presentations of homotopy skein modules of oriented 3-manifolds


  A new method to derive presentations of skein modules is developed. For the
case of homotopy skein modules it will be shown how the topology of a
3-manifold is reflected in the structure of the module. The freeness problem
for q-homotopy skein modules is solved, and a natural skein module related to
linking numbers is computed.

</DOC>
<DOC>
<DOCNO> 13797 </DOCNO>
On a universal mechanism for long ranged volatility correlations


  We propose a general interpretation for long-range correlation effects in the
activity and volatility of financial markets. This interpretation is based on
the fact that the choice between `active' and `inactive' strategies is
subordinated to random-walk like processes. We numerically demonstrate our
scenario in the framework of simplified market models, such as the Minority
Game model with an inactive strategy. We show that real market data can be
surprisingly well accounted for by these simple models.

</DOC>
<DOC>
<DOCNO> 170725 </DOCNO>
Resonant photon creation in a three dimensional oscillating cavity


  We analyze the problem of photon creation inside a perfectly conducting,
rectangular, three dimensional cavity with one oscillating wall. For some
particular values of the frequency of the oscillations the system is resonant.
We solve the field equation using multiple scale analysis and show that the
total number of photons inside the cavity grows exponentially in time. This is
also the case for slightly off-resonance situations. Although the spectrum of a
cavity is in general non equidistant, we show that the modes of the
electromagnetic field can be coupled, and that the rate of photon creation
strongly depends on this coupling. We also analyze the thermal enhancement of
the photon creation.

</DOC>
<DOC>
<DOCNO> 14091 </DOCNO>
Some remarks about quantum diffusion for Hubbard models


  Some exact results are given, that connect, for a general magnitude of the
interaction term $U$, the repulsive and attractive Hubbard model, in terms of
the eigenspectra and quantum diffusion properties. In particular, it is shown
that, for some initial conditions, the quantum evolution cannot differenciate
between the attractive and repulsive models. These results apply to both
fermionic and bosonic models, in any dimension and for general filling, as far
as the underlying structure is bipartite.

</DOC>
<DOC>
<DOCNO> 39722 </DOCNO>
Three generation neutrino mixing is compatible with all experiments


  We consider the minimal extension of the Standard Model with three
generations of massive neutrinos that mix. We then determine the parameters of
the model that satisfy all experimental constraints.

</DOC>
<DOC>
<DOCNO> 10757 </DOCNO>
The connection between superconducting phase correlations and spin


  One of the most striking universal properties of the
high-transition-temperature (high-$T_c$) superconductors is that they are all
derived from the hole-doping of their insulating antiferromagnetic (AF) parent
compounds. From the outset, the intimate relationship between magnetism and
superconductivity in these copper-oxides has intrigued researchers. Evidence
for this link comes from neutron scattering experiments that show the
unambiguous presence of short-range AF correlations (excitations) in cuprate
superconductors. Even so, the role of such excitations in the pairing mechanism
and superconductivity is still a subject of controversy. For
YBa$_2$Cu$_3$O$_{6+x}$, where $x$ controls the hole-doping level, the most
prominent feature in the magnetic excitations spectra is the ``resonance''.
Here we show that for underdoped YBa$_2$Cu$_3$O$_{6.6}$, where $x$ and $T_c$
are below the optimal values, modest magnetic fields suppress the resonance
significantly, much more so for fields approximately perpendicular rather than
parallel to the CuO$_2$ planes. Our results indicate that the resonance
measures pairing and phase coherence, suggesting that magnetism plays an
important role in the superconductivity of cuprates. The persistence of a field
effect above $T_c$ favors mechanisms with preformed pairs in the normal state
of underdoped cuprates.

</DOC>
<DOC>
<DOCNO> 39617 </DOCNO>
A New Method for Searching for Free Fractional Charge Particles in Bulk


  We present a new experimental method for searching for free fractional charge
in bulk matter; this new method derives from the traditional Millikan liquid
drop method, but allows the use of much larger drops, 20 to 100 mm in diameter,
compared to the traditional method that uses drops less than 15 mm in diameter.
These larger drops provide the substantial advantage that it is then much
easier to consistently generate drops containing liquid suspensions of powdered
meteorites and other special minerals. These materials are of great importance
in bulk searches for fractional charge particles that may have been produced in
the early universe.

</DOC>
<DOC>
<DOCNO> 120352 </DOCNO>
Large scale dynamos with ambipolar diffusion nonlinearity


  It is shown that ambipolar diffusion as a toy nonlinearity leads to very
similar behaviour of large scale turbulent dynamos as full MHD. This is
demonstrated using both direct simulations in a periodic box and a closure
model for the magnetic correlation functions applicable to infinite space.
Large scale fields develop via a nonlocal inverse cascade as described by the
alpha-effect. However, because magnetic helicity can only change on a resistive
timescale, the time it takes to organize the field into large scales increases
with magnetic Reynolds number.

</DOC>
<DOC>
<DOCNO> 99972 </DOCNO>
The generalized Chern character and Lefschetz numbers in W*-modules


  We define N-theory being some analogue of K-theory on the category of von
Neumann algebras such that $K_0(A)\subset N_0(A)$ for any von Neumann algebra
A. Moreover, it turns out to be possible to construct the extension of the
Chern character to some homomorphism from $N_0(A)$ to even Banach cyclic
homology of A. Also, we define generalized Lefschetz numbers for an arbitrary
unitary endomorphism U of an A-elliptic complex. We study them in the situation
when U is an element of a representation of some compact Lie group.

</DOC>
<DOC>
<DOCNO> 9016 </DOCNO>
Stripe orders in the extended Hubbard model


  We study stripe orders of charge and spin density waves in the extended
Hubbard model with the nearest-neighbor Coulomb repulsion V within the mean
field approximation. We obtain V vs. T(temperature) phase diagram for the
on-site Coulomb interaction U/t=8.0 and the filling n=0.8, here t is a
nearest-neighbor transfer energy. Our result shows that the diagonal stripe
spin density wave state (SDW) is stable for small V, but for large V the most
stable state changes to a charge density wave-antiferromagnetic (CDW-AF) state.
Especially we find at low temperature and for a certain range of value of V, a
vertical stripe CDW-AF state becomes stable.

</DOC>
<DOC>
<DOCNO> 101434 </DOCNO>
Closed Loop Solitons and Sigma Functions: Classical and Quantized


  Closed loop solitons in a plane, whose curvatures obey the modified
Korteweg-de Vries equation, were investigated. It was shown that their
tangential vectors are expressed by ratio of Weierstrass sigma functions for
genus one case and ratio of Baker's sigma functions for the genus two case.
This study is closely related to classical and quantized elastica problems.

</DOC>
<DOC>
<DOCNO> 13415 </DOCNO>
Stochastic Aggregation of Point Particles Revisited


  In the present letter we employ the method of the dynamical renormalisation
group to compute the average mass distribution of aggregating point particles
in 2 dimensions in the regime when the effects of local mass distribution
fluctuations are essential

</DOC>
<DOC>
<DOCNO> 10994 </DOCNO>
Quasi-Particle density of states of disordered d-wave superconductors


  We present a numerical study of the quasi-particle density of states
  (DoS) of two-dimensional d-wave superconductors in the presence of
  smooth disorder. We find power law scaling of the DoS with an
  exponent depending on the strength of the disorder and the
  superconducting order parameter in quantitative agreement with the
  theory of Nersesyan et al. (Phys.Rev.Lett. 72,
  2628 (1994)). For strong disorder a transition to a constant DoS
  occurs. Our results are in contrast to the case of short-ranged
  disorder.

</DOC>
<DOC>
<DOCNO> 13134 </DOCNO>
Dark soliton creation in Bose-Einstein condensates


  It is demonstrated that stable, standing dark solitons can be created in
current dilute-gas Bose-Einstein condensate experiments by the proper
combination of phase and density engineering. Other combinations result in a
widely controllable range of grey solitons. The phonon contribution is small
and is calculated precisely. The ensuing dynamics should be observable in situ,
i.e. without ballistic expansion of the condensate.

</DOC>
<DOC>
<DOCNO> 119211 </DOCNO>
Abundances of light elements in metal-poor stars. IV. [Fe/O] and [Fe/Mg]


  The accurate O, Mg and Fe abundances derived in previous papers of this
series from a homogenous reanalysis of high quality data for a large sample of
stars are combined with stellar kinematics in order to discuss the history of
star formation in the solar neighborhood. We found that the Fe/O and Fe/Mg
abundance ratios are roughly constant in the (inner) halo and the thick disk;
this means that the timescale of halo collapse was shorter than or of the same
order of typical lifetime of progenitors of type Ia SNe (~ 1 Gyr), this
conclusion being somewhat relaxed (referring to star formation in the
individual fragments) in an accretion model for the Galaxy formation. Both Fe/O
and Fe/Mg ratios raised by ~ 0.2 dex while the O/H and Mg/H ratios hold
constant during the transition from the thick to thin disk phases, indicating a
sudden decrease in star formation in the solar neighbourhood at that epoch.
These results are discussed in the framework of current views of Galaxy
formation; they fit in a scenario where both dissipational collapse and
accretions were active on a quite similar timescale.

</DOC>
<DOC>
<DOCNO> 69563 </DOCNO>
Kahler Normal Coordinate Expansion in Supersymmetric Theories


  The Riemann normal coordinate expansion method is generalized to a Kahler
manifold. The Kahler potential and holomorphic coordinate transformations are
used to define a normal coordinate preserving the complex structure. The
existence of this Kahler normal coordinate is shown explicitly to all orders.
The formalism is applied to background field methods in supersymmetric
nonlinear sigma models.

</DOC>
<DOC>
<DOCNO> 85076 </DOCNO>
Energy-momentum of the gravitational field in the teleparallel geometry


  The Hamiltonian formulation of the teleparallel equivalent of general
relativity without gauge fixing has recently been established in terms of the
Hamiltonian constraint and a set of six primary constraints. Altogether, they
constitute a set of first class constraints. In view of the constraint
structure we establish definitions for the energy, momentum and angular
momentum of the gravitational field. In agreement with previous investigations,
the gravitational energy-momentum density follows from a total divergence that
arises in the constraints. This definition is applied successfully to the
calculation of the irreducible mass of the Kerr black hole. The definition of
the algular momentum of the gravitational field follows from the integral form
of primary constraints that satisfy the angular momentum algebra.

</DOC>
<DOC>
<DOCNO> 116679 </DOCNO>
Solution of the Scalar Coulomb Bethe-Salpeter Equation


  A relativistic two-body wave equation, local in configuration space, is
derived from the Bethe-Salpeter equation for two scalar particles bound by a
scalar Coulomb interaction. The two-body bound-state wave equation is solved
analytically, giving a two-body Bohr-Sommerfeld formula whose energies agree
with the Bethe-Salpeter equation to order alpha^4 for all quantum states. From
the Bohr-Sommerfeld formula, along with the expectation values of two remaining
small corrections, the energy levels of the scalar Coulomb Bethe-Salpeter
equation are worked out to order alpha^6 for all states.

</DOC>
<DOC>
<DOCNO> 121492 </DOCNO>
The Case Against Cosmology


  It is argued that some of the recent claims for cosmology are grossly
overblown. Cosmology rests on a very small database: it suffers from many
fundamental difficulties as a science (if it is a science at all) whilst
observations of distant phenomena are difficult to make and harder to
interpret. It is suggested that cosmological inferences should be tentatively
made and sceptically received.

</DOC>
<DOC>
<DOCNO> 9505 </DOCNO>
Emission Spectrum of a Dipole in a Semi-infinite Periodic Dielectric


  The emission spectrum of a dipole embedded in a semi-infinite photonic
crystal is calculated. For simplicity we study the case in which the dielectric
function is sinusoidally modulated only along the direction perpendicular to
the boundary surface plane. In addition to oscillations of the emission rate
with the distance of the dipole from the interface we also observed that the
shape of the emission spectrum srongly depends on the $\em initial$ $\em phase$
of the dielectric modulation. When the direction of light propagation inside
the periodic structure is not normal to the boundary surface plane we observed
aditional singularities in the emission spectrum, which arise due to different
angle-dependence of the Bragg stop-band for $TE$ and $TM$ polarizations.

</DOC>
<DOC>
<DOCNO> 70035 </DOCNO>
The impact of atomic precision measurements in high energy physics


  In this talk I discuss the relevance of atomic physics in understanding some
important questions about elementary particle physics. A particular attention
is devoted to atomic parity violation measurements which seem to suggest new
physics beyond the Standard Model. Atomic physics might also be relevant in
discovering possible violations of the CPT symmetry.

</DOC>
<DOC>
<DOCNO> 11743 </DOCNO>
Osmotic Pressure of Solutions Containing Flexible Polymers Subject to an


  The osmotic pressure $P$ in equilibrium polymers (EP) in good solvent is
investigated by means of a three dimensional off-lattice Monte Carlo
simulation. Our results compare well with real space renormalisation group
theory and the osmotic compressibility $K \propto \phi \upd \phi/\upd P$ from
recent light scattering study of systems of long worm-like micelles. We confirm
the scaling predictions for EP based on traditional physics of quenched
monodisperse polymers in the dilute and semidilute limit. Specifically, we find
$P\propto \phi^{2.3}$ and, hence, $K \propto \phi^{-0.3}$ in the semidilute
regime --- in agreement with both theory and experiment. At higher
concentrations where the semidilute blobs become too small and hard-core
interactions and packing effects become dominant, a much stronger increase %
$\log(P/\phi)\approx \log(\Nav^2/\phi) \propto \phi$ is evidenced and,
consequently, the compressibility decreases much more rapidly with $\phi$ than
predicted from semidilute polymer theory, but again in agreement with
experiment.

</DOC>
<DOC>
<DOCNO> 8903 </DOCNO>
Data clustering and noise undressing of correlation matrices


  We discuss a new approach to data clustering. We find that maximum likelyhood
leads naturally to an Hamiltonian of Potts variables which depends on the
correlation matrix and whose low temperature behavior describes the correlation
structure of the data. For random, uncorrelated data sets no correlation
structure emerges. On the other hand for data sets with a built-in cluster
structure, the method is able to detect and recover efficiently that structure.
Finally we apply the method to financial time series, where the low temperature
behavior reveals a non trivial clustering.

</DOC>
<DOC>
<DOCNO> 116576 </DOCNO>
CERN as a Non-School Resource for Science Education


  As a large international research laboratory, CERN feels it has a special
responsibility for outreach, and has many activities directed towards schools,
including organized visits, an on-site museum, hands-on experiments, a Summer
intern programme for high-school teachers, lecture series and webcasts. Ongoing
activities and future plans are reviewed, and some ideas stimulated by this
workshop are offered concerning the relevance of CERN's experience to Asia, and
the particular contribution that CERN can make as a non-school resource for
science education.

</DOC>
<DOC>
<DOCNO> 174449 </DOCNO>
A New Measurement of the Muon Magnetic Anomaly


  The muon magnetic anomaly may contain contributions from physics beyond the
standard model. At the Brookhaven National Laboratory (BNL) a precision
experiment aims for a measurement of the muon magnetic anomaly $a_{\mu}$ to
0.35 ppm, where conclusions about various theoretical approaches beyond
standard theory can be expected. The difference between the spin precession and
cyclotron frequencies is measured in a magnetic storage ring with highly
homogeneous field. Data taking is in progress and part of all recorded data has
been analyzed. Combining all experimental results to date yields preliminarily
$a_{\mu}(expt)=1~165~921(5) \cdot 10^{-9}$ (4 ppm) in agreement with standard
theory.

</DOC>
<DOC>
<DOCNO> 121470 </DOCNO>
Non-LTE Modeling of Nova Cygni 1992


  We present a grid of nova models that have an extremely large number of
species treated in non-LTE, and apply it to the analysis of an extensive time
series of ultraviolet spectroscopic data for Nova Cygni 1992. We use
ultraviolet colors to derive the time development of the effective temperature
of the expanding atmosphere during the fireball phase and the first ten days of
the optically thick wind phase. We find that the nova has a pure optically
thick wind spectrum until about 10 days after the explosion. During this
interval, we find that synthetic spectra based on our derived temperature
sequence agree very well with the observed spectra. We find that a sequence of
hydrogen deficient models provides an equally good fit providing the model
effective temperature is shifted upwards by ~1000 K. We find that high
resolution UV spectra of the optically thick wind phase are fit moderately well
by the models. We find that a high resolution spectrum of the fireball phase is
better fit by a model with a steep density gradient, similar to that of a
supernova, than by a nova model.

</DOC>
<DOC>
<DOCNO> 69985 </DOCNO>
Remark on approximation in the calculation of the primordial spectrum


  We re-examine approximations in the analytical calculation of the primordial
spectrum of cosmological perturbation produced during inflation. Taking two
inflation models (chaotic inflation and natural inflation) as examples, we
numerically verify the accuracy of these approximations.

</DOC>
<DOC>
<DOCNO> 151420 </DOCNO>
New modular invariance in the N=1* theory, operator mixings and


  We discuss the mass-deformed N=4 SU(N) supersymmetric Yang-Mills theory (also
known as the N=1* theory). We analyze how the correlation functions of this
theory transform under S-duality, and which correlation functions depend
holomorphically on the complexified gauge coupling \tau. We provide exact
modular-covariant expressions for the vacuum expectation values of chiral
operators in the massive vacua of the N=1* theory. We exhibit a novel modular
symmetry of the chiral sector of the theory in each vacuum, which acts on the
coupling ${\tilde \tau}= (p\tau+k)/q$, where p, k and q are integers which
label the different vacua. In the strong coupling limit, we compare our results
to the results of Polchinski and Strassler in the string theory dual of this
theory, and find non-trivial agreement after operator mixings are taken into
account. In particular we find that their results are consistent with the
predicted modular symmetry in ${\tilde \tau}$. Our results imply that certain
singularities found in solutions to five dimensional gauged supergravity should
not be resolvable in string theory, since there are no field theory vacua with
corresponding vacuum expectation values in the large N limit.

</DOC>
<DOC>
<DOCNO> 102657 </DOCNO>
A Remark on the Deformation of GNS Representations of *-Algebras


  Motivated by deformation quantization we investigate the algebraic GNS
construction of *-representations of deformed *-algebras over ordered rings and
compute their classical limit. The question if a GNS representation can be
deformed leads to the deformation of positive linear functionals. Various
physical examples from deformation quantization like the Bargmann-Fock and the
Schr{\"o}dinger representation as well as KMS functionals are discussed.

</DOC>
<DOC>
<DOCNO> 99804 </DOCNO>
The Flag Major Index and Group Actions on Polynomial Rings


  A new extension of the major index, defined in terms of Coxeter elements, is
introduced. For the classical Weyl groups of type $B$, it is equidistributed
with length. For more general wreath products it appears in an explicit formula
for the Hilbert series of the (diagonal action) invariant algebra.

</DOC>
<DOC>
<DOCNO> 122853 </DOCNO>
The bulge luminosity functions in the MSX infrared bands


  We use an inversion technique to derive the luminosity functions of the
Galactic bulge from point source counts extracted from the Midcourse Space
Experiment's Point Source Catalog (version 1.2).

</DOC>
<DOC>
<DOCNO> 9878 </DOCNO>
Coherent Optics and Localized Light


  Interplay between the effects of coherent radiation and localization of light
is analysed. A system of two-level atoms is placed in a medium interacting with
electromagnetic field. The matter-light interaction can result in the
appearance of a band gap in the spectrum of polariton states. If an atom with a
resonance frequency inside the gap is incorporated into such a medium, the
atomic spontaneous emission is suppressed, which is termed the localization of
light. However, a system of resonance atoms inside the gap can radiate due to
their coherent interactions. The peculiarity of the coherent radiation by a
system of atoms, under the localization of light for a single atom, is studied.

</DOC>
<DOC>
<DOCNO> 117811 </DOCNO>
The Distribution of Stellar Orbits in the Giant Elliptical Galaxy NGC


  We present direct observational constraints on the orbital distribution of
the stars in the giant elliptical NGC 2320. Long-slit spectra along multiple
position angles are used to derive the stellar line-of-sight velocity
distribution within one effective radius. In addition, the rotation curve and
dispersion profile of an ionized gas disk are measured from the [OIII] emission
lines. After correcting for the asymmetric drift, we derive the circular
velocity of the gas, which provides an independent constraint on the
gravitational potential.
  To interpret the stellar motions, we build axisymmetric three-integral
dynamical models based on an extension of the Schwarzschild orbit-
superposition technique. We consider two families of gravitational potential,
one in which the mass follows the light (i.e. no dark matter) and one with a
logarithmic gravitational potential. Using chi^2-statistics, we compare our
models to both the stellar and gas data to constrain the value of the V-band
mass-to-light ratio Upsilon-V. We find Upsilon-V = 15.0 \pm 0.6 h75 for the
mass-follows-light models and Upsilon-V = 17.0 \pm 0.7 h75 for the logarithmic
models. For the latter, Upsilon-V is defined within a sphere of 15'' radius.
  Models with radially constant Upsilon-V and logarithmic models with dark
matter provide comparably good fits to the data and possess similar dynamical
structure. Across the full range of Upsilon-V permitted by the observational
constraints, the models are radially anisotropic in the equatorial plane over
the radial range of our kinematical data (1'' < r < 40''). Along the true minor
axis, they are more nearly isotropic. (abridged)

</DOC>
<DOC>
<DOCNO> 9798 </DOCNO>
Metastable states in glassy systems


  Truly stable metastable states are an artifact of the mean-field
approximation or the zero temperature limit. If such appealing concepts in
glass theory as configurational entropy are to have a meaning beyond these
approximations, one needs to cast them in a form involving states with finite
lifetimes.
 Starting from elementary examples and using results of Gaveau and Schulman, we
propose a simple expression for the configurational entropy and revisit the
question of taking flat averages over metastable states. The construction is
applicable to finite dimensional systems, and we explicitly show that for
simple mean-field glass models it recovers, justifies and generalises the known
results. The calculation emphasises the appearance of new dynamical order
parameters.

</DOC>
<DOC>
<DOCNO> 11653 </DOCNO>
Schulman Replies


  This is a reply to a comment of Casati, Chirikov and Zhirov (PRL 85, 896
(2000)) on PRL 83, 5419 (1999).
  The suitability of the particlar two-time boundary value problem used in the
earlier PRL is argued.

</DOC>
<DOC>
<DOCNO> 9562 </DOCNO>
Generating entangled atom-photon pairs from Bose-Einstein condensates


  We propose using spontaneous Raman scattering from an optically driven
Bose-Einstein condensate as a source of atom-photon pairs whose internal states
are maximally entangled. Generating entanglement between a particle which is
easily transmitted (the photon) and one which is easily trapped and coherently
manipulated (an ultracold atom) will prove useful for a variety of
quantum-information related applications. We analyze the type of entangled
states generated by spontaneous Raman scattering and construct a geometry which
results in maximum entanglement.

</DOC>
<DOC>
<DOCNO> 121910 </DOCNO>
Clusters of Galaxies: Diagnostic Tools for Cosmology


  Clusters of galaxies can be used for very different kinds of cosmological
tests. I review a few of the methods: determination of cluster masses and dark
matter content, metal enrichment and its connection to the origin of the
intra-cluster gas, and the dynamical state of clusters. The progress in the
different fields expected from observations with the new X-ray satellites XMM
and Chandra is pointed out.

</DOC>
<DOC>
<DOCNO> 120263 </DOCNO>
Iron K line emission in AGN: observations


  Iron K-alpha lines are key diagnostics of the central regions of AGN. Their
profiles indicate that they are formed deep in the potential well of the
central black hole, where extreme broadening and red shift occur. The profiles
are most easily reproducible in an accretion disk: the lack of significant
emission blue-ward of the rest energy is difficult produce in other geometries.
In one source an apparent (and perhaps variable) absorption feature in the red
wing of the line may represent rare evidence for inflow onto the black hole.
Sample analysis has defined the mean properties, showing a strong concentration
of the emission in the central regions and face-on accretion disks, at least in
Seyfert 1 galaxies. Surprising results have been obtained from examination of
the line variability. Strong profile changes may be accounted for by changes in
the illumination pattern of the central, relativistic part of the disk. In at
least the case of MCG-6-30-15, there is evidence for emission from within 6
R_g, possibly indicating a spinning black hole. Developing an understanding of
these complex changes has the potential to reveal the geometry and kinematics
of the inner few gravitational radii around extragalactic black holes.

</DOC>
<DOC>
<DOCNO> 122940 </DOCNO>
The Nuclei of Nearby Radio-Loud Ellipticals


  We have observed a complete sample of 21 nearby (D < 70h^{-1} Mpc) Fanaroff &
Riley Type I galaxies with HST/WFPC2 and detected dust disks and lanes in 19 of
them. The radio jets are roughly perpendicular to the dust which is used to
constrain the Doppler boosting factors of the radio jet and cores. The VLBA
core flux correlates with the central Halpha+[NII] flux which might indicate
that the VLBA core is dominated by an isotropic component. Twelve galaxies show
nuclear optical sources. We discuss various possible origins for this emission.

</DOC>
<DOC>
<DOCNO> 120322 </DOCNO>
Mid-infrared interferometry on spectral lines: III. Ammonia and Silane


  Using the U.C. Berkeley Infrared Spatial Interferometer with an RF
filterbank, the first interferometric observations of mid-infrared molecular
absorption features of ammonia (NH_3) and silane (SiH_4) with very high
spectral resolution (R ~ 100000) were made. Under the assumptions of spherical
symmetry and uniform outflow, these new data permitted the molecular
stratification around carbon star IRC+10216 and red supergiant VY CMa to be
investigated. For IRC+10216, both ammonia and silane were found to form in the
dusty outflow significantly beyond both the dust formation and gas acceleration
zones. Specifically, ammonia was found to form before silane in a region of
decaying gas turbulence (>~ 20 R_star), while the silane is produced in a
region of relatively smooth gas flow much further from the star (>~ 80 R_star).
The depletion of gas-phase SiS onto grains soon after dust formation may fuel
silane-producing reactions on the grain surfaces. For VY CMa, a combination of
interferometric and spectral observations suggest that NH_3 is forming near the
termination of the gas acceleration phase in a region of high gas turbulence (~
40 R_star).

</DOC>
<DOC>
<DOCNO> 13671 </DOCNO>
Probing interactions in mesoscopic gold wires


  We have measured in gold wires the energy exchange rate between
quasiparticles, the phase coherence time of quasiparticles and the resistance
vs. temperature, in order to probe the interaction processes which are relevant
at low temperatures. We find that the energy exchange rate is higher than
expected from the theory of electron-electron interactions, and that it has a
different energy dependence. The dephasing time is constant at temperatures
between 8 K and 0.5 K, and it increases below 0.5 K. The magnetoresistance is
negative at large field scales, and the resistance decreases logarithmically
with increasing temperatures, indicating the presence of magnetic impurities,
probably Fe. Whereas resistivity and phase coherence measurements can be
attributed to magnetic impurities, the question is raised whether these
magnetic impurities could also mediate energy exchanges between quasiparticles.

</DOC>
<DOC>
<DOCNO> 84892 </DOCNO>
Demonstration of detuned dual recycling at the Garching 30m laser


  Dual recycling is an advanced optical technique to enhance the
signal-to-noise ratio of laser interferometric gravitational wave detectors in
a limited bandwidth. To optimise the center of this band with respect to
Fourier frequencies of expected gravitational wave signals detuned dual
recycling has to be implemented. We demonstrated detuned dual recycling on a
fully suspended 30m prototype interferometer. A control scheme that allows to
tune the detector to different frequencies will be outlined. Good agreement
between the experimental results and numerical simulations has been achieved.

</DOC>
<DOC>
<DOCNO> 10640 </DOCNO>
The problem of uniqueness in the reduced description of adsorption on


  In the reduced one-dimensional description of the adsorption on the
wedge-shaped substrate the mid-point interface height serves as the order
parameter. We point at the ambiguity which appears in the transfer-matrix
approach to this problem. We also propose how to avoid this problem by
introducing the appropriate order parameter.

</DOC>
<DOC>
<DOCNO> 11430 </DOCNO>
Multiphase segregation and metal-insulator transition in single crystal


  The insulator-metal transition in single crystal La(5/8-y)Pr(y)Ca(3/8)MnO3
with y=0.35 was studied using synchrotron x-ray diffraction, electric
resistivity, magnetic susceptibility, and specific heat measurements. Despite
the dramatic drop in the resistivity at the insulator-metal transition
temperature Tmi, the charge-ordering (CO) peaks exhibit no anomaly at this
temperature and continue to grow below Tmi. Our data suggest then, that in
addition to the CO phase, another insulating phase is present below Tco. In
this picture, the insulator-metal transition is due to the changes within this
latter phase. The CO phase does not appear to play a major role in this
transition. We propose that a percolation-like insulator-metal transition
occurs via the growth of ferromagnetic metallic domains within the parts of the
sample that do not exhibit charge ordering. Finally, we find that the
low-temperature phase-separated state is unstable against x-ray irradiation,
which destroys the CO phase at low temperatures.

</DOC>
<DOC>
<DOCNO> 9499 </DOCNO>
On Fermi systems with strong forward scattering in d spatial dimensions


  We consider a specific generalisation to spatial dimensions d greater than
one of a formalism based upon conservation laws and the associated Ward
identities, that exactly solves the one-dimensional Luttinger model, and expose
its inadequacies for d > 1. We conclude that findings arrived at through
application of this generalised formalism concerning systems of fermions with
strong forward scattering, in particular that d=1 would be the cross-over
dimension from Luttinger- to Fermi-liquid state, are open to question.

</DOC>
<DOC>
<DOCNO> 118866 </DOCNO>
Limits on the optical magnitude of PSR 1821-24 in M28


  The detection of a pulsed X-ray counterpart (RX J1824.2-2R52P) of the 3.05 ms
pulsar PSR 1821-24, suggests the possibility of a part of the rotational energy
loss of this high spindown rate pulsar being in the optical band. Archival HST
data for M28 is used here to set upper limits on the optical V-band magnitude
of PSR 1821-24. The optical limit extends the multiwavelength observations for
this source and provides a constraint for theoretical models of pulsar
emission.

</DOC>
<DOC>
<DOCNO> 85650 </DOCNO>
On junction conditions in gravity theories with higher curvature terms


  We discuss the junction conditions in the context of the Randall-Sundrum
model with the Gauss-Bonnet interaction. We consider the $Z_2$ symmetric model
where the brane is embedded in an $AdS_5$ bulk, as well as a model without
$Z_2$ symmetry in which the brane (in this case called by tradition ``shell'')
separates two metrically different $AdS_5$ regions. We show that the Israel
junction conditions across the membrane (that is either a brane or a shell)
have to be modified if more general equations than Einstein's, including higher
curvature terms, hold in the bulk, as is likely to be the case in a low energy
limit of string theory. We find that the membrane can then no longer be treated
in the thin wall approximation. We derive the junction conditions for the
Einstein-Gauss-Bonnet theory including second order curvature terms and show
that the microphysics of Gauss-Bonnet thick membranes may, in some instances,
be simply hidden in a renormalization of Einstein's constant.

</DOC>
<DOC>
<DOCNO> 13158 </DOCNO>
Mechanisms of Spontaneous Current Generation in an Inhomogeneous d-Wave


  A boundary between two d-wave superconductors or an s-wave and a d-wave
superconductor generally breaks time-reversal symmetry and can generate
spontaneous currents due to proximity effect. On the other hand, surfaces and
interfaces in d-wave superconductors can produce localized current-carrying
states by supporting the T-breaking combination of dominant and subdominant
order parameters. We investigate spontaneous currents in the presence of both
mechanisms and show that at low temperature, counter-intuitively, the
subdominant coupling decreases the amplitude of the spontaneous current due to
proximity effect. Superscreening of spontaneous currents is demonstrated to be
present in any d-d (but not s-d) junction and surface with d+id' order
parameter symmetry. We show that this supercreening is the result of
contributions from the local magnetic moment of the condensate to the
spontaneous current.

</DOC>
<DOC>
<DOCNO> 71373 </DOCNO>
Photoproduction of charm near threshold


  Charm and bottom production near threshold is sensitive to the multi-quark,
gluonic, and hidden-color correlations of hadronic and nuclear wavefunctions in
QCD since all of the target's constituents must act coherently within the small
interaction volume of the heavy quark production subprocess. Although such
multi-parton subprocess cross sections are suppressed by powers of $1/m^2_Q$,
they have less phase-space suppression and can dominate the contributions of
the leading-twist single-gluon subprocesses in the threshold regime. The small
rates for open and hidden charm photoproduction at threshold call for a
dedicated facility.

</DOC>
<DOC>
<DOCNO> 69620 </DOCNO>
Mikheyev-Smirnov-Wolfenstein Effect for Linear Electron Density


  When the electron density is a linear function of distance, it is known that
the MSW equations for two neutrino species can be solved in terms of known
functions. It is shown here that more generally, for any number of neutrino
species, these MSW equations can be solved exactly in terms of single
integrals. While these integrals cannot be expressed in terms of known
functions, some of their simple properties are obtained. Application to the
solar neutrino problem is briefly discussed.

</DOC>
<DOC>
<DOCNO> 102056 </DOCNO>
Irreducible subfactors of $L(\mathbb F_\infty)$ of index $\lambda>4$


  By utilizing an irreducible inclusion of type III$_{q^{2}} $ factors coming
from a free-product type action of the quantum group $ SU_{q}(2) $, we show
that the free group factor $ L(\mathbb {F}_{\infty}) $ possesses irreducible
subfactors of arbitrary index $ >4 $. Combined with earlier results of
Radulescu, this shows that $ L(\mathbb {F}_{\infty}) $ has irreducible
subfactors with any index value in $ \{4\cos ^{2}(\pi /n):n\geq 3\}\cup
[4,+\infty) $.

</DOC>
<DOC>
<DOCNO> 102553 </DOCNO>
Some light on Littlewood-Paley theory


  The purpose of this note is to correct an error in a paper of M. Cowling, G.
Fendler and J.J.F. Fournier, and to give a counterexample to a conjecture of
J.-L. Rubio de Francia.

</DOC>
<DOC>
<DOCNO> 13794 </DOCNO>
Spin dynamics in nonlinear optical spectroscopy of Fermi sea systems


  We discuss the role of many-body spin correlations in nonlinear optical
response of a Fermi sea system with a deep impurity level. Due to the Hubbard
repulsion between electrons at the impurity, the optical transitions between
the impurity level and the Fermi sea states lead to an optically-induced Kondo
effect. In particular, the third-order nonlinear optical susceptibility
logarithmiclly diverges at the absorption threshold. The shape of the
pump-probe spectrum is governed by the light-induced Kondo temperature, which
can be tuned by varying the intensity and frequency of the pump optical field.
In the Kondo limit, corresponding to off-resonant pump excitation, the
nonlinear absorption spectrum exhibits a narrow peak below the linear
absorption onset.

</DOC>
<DOC>
<DOCNO> 69607 </DOCNO>
Sudden Hadronization in Relativistic Nuclear Collisions


  We formulate and study a mechanical instability criterion for sudden
hadronization of dense matter fireballs formed in 158A GeV Pb--Pb collisions.
Considering properties of quark-gluon matter and hadron gas we obtain the phase
boundary between these two phases and demonstrate that the required deep QGP
supercooling prior to sudden hadronization has occurred.

</DOC>
<DOC>
<DOCNO> 12512 </DOCNO>
Spin orbit effects in a GaAs quantum dot in a parallel magnetic field


  We analyze the effects of spin-orbit coupling on fluctuations of the
conductance of a quantum dot fabricated in a GaAs heterostructure. We argue
that spin-orbit effects may become important in the presence of a large
parallel magnetic field B_{||}, even if they are negligble for B_{||}=0. This
should be manifest in the level repulsion of a closed dot, and in reduced
conductance fluctuations in dots with a small number of open channels in each
lead, for large B_{||}. Our picture is consistent with the experimental
observations of Folk et al.

</DOC>
<DOC>
<DOCNO> 151558 </DOCNO>
The dynamics of zeros of the finite-gap solutions to the Schrodinger


  Following the recent paper by J. F. van Diejen and H. Puschmann we
investigate the behavior of zeros of the finite-gap solutions to the
Schrodinger equation. As a result, a new system of particles on a punctured
Riemann surface is constructed. It is shown to be Hamiltonian and integrable.

</DOC>
<DOC>
<DOCNO> 8750 </DOCNO>
Why does a protein fold?


  With the help of lattice Monte Carlo modelling of heteropolymers, we show
that the necessary condition for a protein to fold on short call is to proceed
through partially folded intermediates. These elementary structures are formed
at an early stage in the folding process and contain, at the local level,
essentially all of the amino acids found in the folding core (transition state)
of the protein, providing the local guidance for its formation. The sufficient
condition for the protein to fold is that the designed sequence has an energy,
in the native conformation, below $E_c$ (the lowest energy of the structurally
dissimilar compact conformations) where it has not to compete with the bulk of
misfolded conformations. Sequences with energy close to $E_c$ can display
prion--like behaviour, folding to two structurally dissimilar conformations,
one of them being the native.

</DOC>
<DOC>
<DOCNO> 101482 </DOCNO>
The spectral gap of the 2-D stochastic Ising model with mixed boundary


  We establish upper bounds for the spectral gap of the stochastic Ising model
at low temperatures in an n-by-n box with boundary conditions which are not
purely plus or minus; specifically, we assume the magnitude of the sum of the
boundary spins over each interval of length n in the boundary is bounded by
\delta n, where \delta < 1. We show that for any such boundary condition, when
the temperature is sufficiently low (depending on \delta), the spectral gap
decreases exponentially in n.

</DOC>
<DOC>
<DOCNO> 12078 </DOCNO>
Atomic Solitons in Optical Lattices


  The experimental demonstration of Bose-Einstein condensation in atomic vapors
has rapidly lead to new advances in atom optics. It is now well established
that two-body collisions play for matter waves a role analogous to that of a
Kerr nonlinear crystal in optics. In particular, it is known that the nonlinear
Schr\"odinger equation which describes the condensate supports soliton
solutions. For the case of repulsive interactions normally encountered in BEC
experiments, the simplest solutions are dark solitons, that is, 'dips' in the
density profile of the condensate. However, it is desirable to achieve the
dispersionless transport of a spatially localized ensemble of atoms, rather
than a 'hole'. In that case, bright solitons are much more interesting although
the problem is that large condensates are necessarily associated with repulsive
interactions, for which bright solitons might seem impossible. While this is
true for atoms in free space, this is however not the case for atoms in
suitable potentials, eg. optical lattices. This result is known from nonlinear
optics, where such soliton solutions, called gap solitons, have been predicted
and demonstrated. We will briefly review the basic formalism for nonlinear atom
optics and summarize various soliton solutions and then describe a specific
model for gap solitons in a spinor Bose-Einstein condensate.

</DOC>
<DOC>
<DOCNO> 12091 </DOCNO>
Frequency Dependent Viscosity Near the Critical Point: The Scale to Two


  The recent accurate measurements of Berg, Moldover and Zimmerli of the
viscoelastic effect near the critical point of xenon has shown that the scale
factor involved in the frequency scaling is about twice the scale factor
obtained theoretically. We show that this discrepancy is a consequence of using
first order perturbation theory. Including two loop contribution goes a long
way towards removing the discrepancy.

</DOC>
<DOC>
<DOCNO> 178855 </DOCNO>
Dilepton production in proton-proton collisions at BEVALAC energies


  The dilepton production in elementary proton-proton collisions at BEVALAC
energies T = 1 - 5 GeV is investigated. The subthreshold vector meson
production cross sections in pp collisions are treated in a way sufficient to
avoid double counting with the inclusive vector meson production. The vector
meson dominance model for the transition form factors of the nucleon resonance
Dalitz decays is extended to ensure correct asymptotics which are in agreement
with the quark counting rules. By such a modification, unified and consistent
description of both $R\to N\gamma $ radiative decays and $R\to N\rho (\omega)$
meson decays is obtained without introducing new parameters. This provides
evidence for the validity of the quark counting rules in the baryon resonance
sector. The effect of multiple pion production on the experimental efficiency
for the detection of the dilepton pairs is studied. We found the dilepton yield
in reasonable agreement with the experimental data for the set of intermediate
energies whereas at the highest energy T = 4.88 GeV the number of dilepton
pairs is likely to be overestimated experimentally in the mass range $M=300\div
700$ MeV. The modification of the $pp\to e^{+}e^{-}X$ cross section due to a
decoherence of the vector meson propagation inside a hot and dense nuclear
medium is discussed.

</DOC>
<DOC>
<DOCNO> 40599 </DOCNO>
First Physics Results at BABAR


  The BABAR detector, which operates at the SLAC PEP-II asymmetric e^+e^-
collider at energies near the Y(4S) resonance, started operation on the 26th of
May 1999. We present the first study of sin2beta, with samples of B0 --> J/psi
K0S and B0 --> psi(2S) K0S decays, using 9.0 fb-1 of data recorded between
January and July 2000 at the Y(4S) resonance and 0.8 fb-1 recorded 40 MeV below
the Y(4S) resonance. A preliminary result of sin2beta = 0.12+/-0.37 (stat) +/-
0.09 (syst) was obtained. Details of the analysis are given. Moreover, we
present measurements of charged and neutral B meson lifetimes and B^0 B^0bar
oscillation frequency.

</DOC>
<DOC>
<DOCNO> 170403 </DOCNO>
Sympathetic ground state cooling and coherent manipulation with


  We have cooled a two-ion-crystal to the ground state of its collective modes
of motion. Laser cooling, more specific resolved sideband cooling is performed
sympathetically by illuminating only one of the two $^{40}$Ca$^+$ ions in the
crystal. The heating rates of the motional modes of the crystal in our linear
trap have been measured, and we found them considerably smaller than those
previously reported by Q. Turchette {\em et. al.} Phys. Rev. A 61, 063418
(2000) in the case of trapped $^9$Be$^+$ ions. After the ground state is
prepared, coherent quantum state manipulation of the atomic population can be
performed. Within the coherence time, up to 12 Rabi oscillations are observed,
showing that many coherent manipulations can be achieved. Coherent excitation
of each ion individually and ground state cooling are important tools for the
realization of quantum information processing in ion traps.

</DOC>
<DOC>
<DOCNO> 119684 </DOCNO>
Strong Evolution in the Luminosity-Velocity Relation at z>1?


  We present a method for constraining the evolution of the galaxy
luminosity-velocity (LV) relation in hierarchical scenarios of structure
formation. The comoving number density of dark-matter halos with circular
velocity of 200 km/s is predicted in favored CDM cosmologies to be nearly
constant over the redshift range 0<z<5. Any observed evolution in the density
of bright galaxies implies in turn a corresponding evolution in the LV
relation. We consider several possible forms of evolution for the zero-point of
the LV relation and predict the corresponding evolution in galaxy number
density. The Hubble Deep Field suggests a large deficit of bright (M_V < -19)
galaxies at 1.4 < z < 2. If taken at face value, this implies a dimming of the
LV zero-point by roughly 2 magnitudes. Deep, wide-field, near-IR selected
surveys will provide more secure measurements to compare with our predictions.

</DOC>
<DOC>
<DOCNO> 9511 </DOCNO>
Transport properties of heterogeneous materials derived from Gaussian


  We investigate the effective conductivity ($\sigma_e$) of a class of
amorphous media defined by the level-cut of a Gaussian random field. The three
point solid-solid correlation function is derived and utilised in the
evaluation of the Beran-Milton bounds. Simulations are used to calculate
$\sigma_e$ for a variety of fields and volume fractions at several different
conductivity contrasts. Relatively large differences in $\sigma_e$ are observed
between the Gaussian media and the identical overlapping sphere model used
previously as a `model' amorphous medium. In contrast $\sigma_e$ shows little
variability between different Gaussian media.

</DOC>
<DOC>
<DOCNO> 123129 </DOCNO>
A Large-Scale Jet and FR I Radio Source in a Spiral Galaxy: The Host


  We have identified a large (~200 kpc), powerful double radio source whose
host galaxy is clearly a disk and most likely a spiral. This FR I radio galaxy
is located very near the center of the RC 0 cluster Abell 428. The existence of
such an object violates a fundamental paradigm for radio loud AGN. In paper I,
we showed that this object was most likely a spiral host with optical line
ratios and colors consistent with an AGN. In this paper, we present new, higher
resolution radio imaging, a radio/mm continuum spectrum for the nucleus, a
detection of HI absorption against the bright radio core, an upper-limit to CO
and the gas mass, and 70 optical redshifts. We confirm the existence of a radio
jet at 20cm extending 42 kpc into the southern lobe. At 3.6cm, we also detect a
nuclear jet similar in length to that in M87 but 10 times weaker. We believe
that this is the first detection of a radio jet on these scales in a disk or
spiral host galaxy. The nuclear radio spectrum is similar to many blazar or QSO
like objects, suggesting that the galaxy harbors an imbedded and obscured AGN.
We model a turnover in the spectrum at low frequencies as Free-Free absorption.
We detect very strong and narrow HI absorption with nearly the entire 20 cm
core continuum absorbed, implying an unusually large optical depth (tau~1). We
suggest that the nucleus is seen through a disk-like distribution of ISM gas,
possibly through a spiral arm or a warp to account for the high column density.
  From the radial velocities, we find that A428 is in fact made up of at least
2 clumps of galaxies separated by 3300 km/s, which are imbedded in a nearly
continuous distribution of galaxies over 13000 km/s in velocity. Thus, the
environment resembles a poor group within a filament viewed end-on.

</DOC>
<DOC>
<DOCNO> 121821 </DOCNO>
Constraining Cosmological Models by the Cluster Mass Function


  We present a comparison between two observational and three theoretical mass
functions for eight cosmological models suggested by the data from the recently
completed BOOMERANG-98 and MAXIMA-1 cosmic microwave background (CMB)
anisotropy experiments as well as peculiar velocities (PVs) and type Ia
supernovae (SN) observations. The cosmological models have been proposed as the
best fit models by several groups. We show that no model is in agreement with
the abundances of X-ray clusters at $\sim 10^{14.7} h^{-1}M_{\odot}$.On the
other hand, we find that the BOOM+MAX+{\sl COBE}:I, Refined Concordance and
$\Lambda$MDM are in a good agreement with the abundances of optical clusters.
The P11 and especially Concordance models predict a slightly lower abundances
than observed at $\sim 10^{14.6} h^{-1}M_{\odot}$. The BOOM+MAX+{\sl COBE}:II
and PV+CMB+SN models predict a slightly higher abundances than observed at
$\sim 10^{14.9} h^{-1}M_{\odot}$. The nonflat MAXIMA-1 is in a fatal conflict
with the observational cluster abundances and can be safely ruled out.

</DOC>
<DOC>
<DOCNO> 99297 </DOCNO>
Signs in the cd-index of Eulerian partially ordered sets


  A graded partially ordered set is Eulerian if every interval has the same
number of elements of even rank and of odd rank. Face lattices of convex
polytopes are Eulerian. For Eulerian partially ordered sets, the flag vector
can be encoded efficiently in the cd-index. The cd-index of a polytope has all
positive entries. An important open problem is to give the broadest natural
class of Eulerian posets having nonnegative cd-index. This paper completely
determines which entries of the cd-index are nonnegative for all Eulerian
posets. It also shows that there are no other lower or upper bounds on
cd-coefficients (except for the coefficient of c^n).

</DOC>
<DOC>
<DOCNO> 80736 </DOCNO>
An Almost Perfect Quantum Lattice Action for Low-energy SU(2)


  We study various representations of infrared effective theory of SU(2)
Gluodynamics as a (quantum) perfect lattice action. In particular we derive a
monopole action and a string model of hadrons from SU(2) Gluodynamics. These
are lattice actions which give almost cut-off independent physical quantities
even on coarse lattices. The monopole action is determined by numerical
simulations in the infrared region of SU(2) Gluodynamics. The string model of
hadrons is derived from the monopole action by using BKT transformation. We
illustrate the method and evaluate physical quantities such as the string
tension and the mass of the lowest state of the glueball analytically using the
string model of hadrons. It turns out that the classical results in the string
model is near to the one in quantum SU(2) Gluodynamics.

</DOC>
<DOC>
<DOCNO> 101384 </DOCNO>
Generalized Lie bialgebroids and Jacobi structures


  The notion of a generalized Lie bialgebroid (a generalization of the notion
of a Lie bialgebroid) is introduced in such a way that a Jacobi manifold has
associated a canonical generalized Lie bialgebroid. As a kind of converse, we
prove that a Jacobi structure can be defined on the base space of a generalized
Lie bialgebroid. We also show that it is possible to construct a Lie
bialgebroid from a generalized Lie bialgebroid and, as a consequence, we deduce
a duality theorem. Finally, some special classes of generalized Lie
bialgebroids are considered: triangular generalized Lie bialgebroids and
generalized Lie bialgebras.

</DOC>
<DOC>
<DOCNO> 178885 </DOCNO>
Collective Modes of Tri-Nuclear Molecules


  A geometrical model for tri-nuclear molecules is presented. An analytical
solution is obtained provided the nuclei, which are taken to be prolately
deformed, are connected in line to each other. Furthermore, the tri-nuclear
molecule is composed of two heavy and one light cluster, the later sandwiched
between the two heavy clusters. A basis is constructed in which Hamiltonians of
more general configurations can be diagonalized. In the calculation of the
interaction between the clusters higher multipole deformations are taken into
account, including the hexadecupole one. A repulsive nuclear core is introduced
in the potential in order to insure a quasi-stable configuration of the system.
The model is applied to three nuclear molecules, namely $^{96}$Sr + $^{10}$Be +
$^{146}$Ba, $^{108}$Mo + $^{10}$Be + $^{134}$Te and $^{112}$Ru + $^{10}$Be +
$^{130}$Sn.

</DOC>
<DOC>
<DOCNO> 174447 </DOCNO>
Phenomenology of the Deuteron Electromagnetic Form Factors


  A rigorous extraction of the deuteron charge form factors from tensor
polarization data in elastic electron-deuteron scattering, at given values of
the 4-momentum transfer, is presented. Then the world data for elastic
electron-deuteron scattering is used to parameterize, in three different ways,
the three electromagnetic form factors of the deuteron in the 4-momentum
transfer range 0-7 fm^-1. This procedure is made possible with the advent of
recent polarization measurements. The parameterizations allow a
phenomenological characterization of the deuteron electromagnetic structure.
They can be used to remove ambiguities in the form factors extraction from
future polarization data.

</DOC>
<DOC>
<DOCNO> 121790 </DOCNO>
Uncovering the Intrinsic Shapes of Elliptical Galaxies. IV. Tests on


  We test the methods developed in previous papers for inferring the intrinsic
shapes of elliptical galaxies, using simulated objects from N-body experiments.
The shapes of individual objects are correctly reproduced to within the
statistical errors; close inspection of the results indicates a small
systematic bias in the sense of underestimating both the triaxiality and
short-to-long axis ratio. We also test the estimation of parent shape
distributions, using samples of independent, randomly oriented objects. The
best results are statistically accurate, but on average the parent
distributions are again slightly biased in the same sense. Using the posterior
probability densities for the individual objects, we estimate the magnitude of
the bias to be less than approximately 0.1 in both shape parameters. The
results support the continued use of these methods on real systems.

</DOC>
<DOC>
<DOCNO> 40146 </DOCNO>
Opportunities for future supernova studies of cosmic acceleration


  We investigate the potential of a future supernova dataset, as might be
obtained by the proposed SNAP satellite, to discriminate among different ``dark
energy'' theories that describe an accelerating Universe. We find that many
such models can be distinguished with a fit to the effective
pressure-to-density ratio, $w$, of this energy. More models can be
distinguished when the effective slope, $dw/dz$, of a changing $w$ is also fit,
but only if our knowledge of the current mass density, $\Omega_m$, is improved.
We investigate the use of ``fitting functions'' to interpret luminosity
distance data from supernova searches, and argue in favor of a particular
preferred method, which we use in our analysis.

</DOC>
<DOC>
<DOCNO> 178564 </DOCNO>
Role of deformation in the nonmesonic decay of light hypernuclei


  We discuss the nonmesonic decay of deformed p-shell hypernuclei. The Nilsson
model with angular momentum projection is employed in order to take into
account the deformation effects. The nonmesonic decay rate and the intrinsic
$\Lambda$ asymmetry parameter decrease as a function of the deformation
parameter, while the ratio of the neutron- to proton-induced decay rates
increases. We find that the deformation effects change these observables by
about 10 % for $^9_{\Lambda}$Be from the spherical limit.

</DOC>
<DOC>
<DOCNO> 170410 </DOCNO>
Comment on "Quantum key distribution without alternative measurements"


  In a recent paper [A. Cabello, Phys. Rev. A 61, 052312 (2000)], a quantum key
distribution protocol based on entanglement swapping was proposed. However, in
this comment, it is shown that this protocol is insecure if Eve use a special
strategy to attack.

</DOC>
<DOC>
<DOCNO> 85216 </DOCNO>
Dilaton Gravity with a Non-minmally Coupled Scalar Field


  We discuss the two-dimensional dilaton gravity with a scalar field as the
source matter. The coupling between the gravity and the scalar, massless, field
is presented in an unusual form. We work out two examples of these couplings
and solutions with black-hole behaviour are discussed and compared with those
found in the literature.

</DOC>
<DOC>
<DOCNO> 170463 </DOCNO>
Fundamental solution method applied to time evolution of two energy


  A method of fundamental solutions has been used to investigate transitions in
two energy level systems with no level crossing in a real time. Compact
formulas for transition probabilities have been found in their exact form as
well as in their adiabatic limit. No interference effects resulting from many
level complex crossings as announced by Joye, Mileti and Pfister (Phys. Rev.
{\bf A44} 4280 (1991)) have been detected in either case. It is argued that
these results of this work are incorrect. However, some effects of Berry's
phases are confirmed.

</DOC>
<DOC>
<DOCNO> 84268 </DOCNO>
Colliding Plane Impulsive Gravitational Waves


  When two non-interacting plane impulsive gravitational waves undergo a
head-on collision, the vacuum interaction region between the waves after the
collision contains backscattered gravitational radiation from both waves. The
two systems of backscattered waves have each got a family of rays (null
geodesics) associated with them. We demonstrate that if it is assumed that a
parameter exists along each of these families of rays such that the modulus of
the complex shear of each is equal then Einstein's vacuum field equations, with
the appropriate boundary conditions, can be integrated systematically to reveal
the well-known solutions in the interaction region. In so doing the mystery
behind the origin of such solutions is removed. With the use of the field
equations it is suggested that the assumption leading to their integration may
be interpreted physically as implying that the energy densities of the two
backscattered radiation fields are equal. With the use of different boundary
conditions this approach can lead to new collision solutions.

</DOC>
<DOC>
<DOCNO> 14056 </DOCNO>
Stability of critical behaviour of weakly disordered systems with


  A field-theoretic description of the critical behaviour of the weakly
disordered systems is given. Directly, for three- and two-dimensional systems a
renormalization analysis of the effective Hamiltonian of model with replica
symmetry breaking (RSB) potentials is carried out in the two-loop
approximation. For case with 1-step RSB the fixed points (FP's) corresponding
to stability of the various types of critical behaviour are identified with the
use of the Pade-Borel summation technique. Analysis of FP's has shown a
stability of the critical behaviour of the weakly disordered systems with
respect to RSB effects and realization of former scenario of disorder influence
on critical behaviour.

</DOC>
<DOC>
<DOCNO> 85491 </DOCNO>
Classical analogous of quantum cosmological perfect fluid models


  Quantization in the mini-superspace of a gravity system coupled to a perfect
fluid, leads to a solvable model which implies singularity free solutions
through the construction of a superposition of the wavefunctions. We show that
such models are equivalent to a classical system where, besides the perfect
fluid, a repulsive fluid with an equation of state $p_Q = \rho_Q$ is present.
This leads to speculate on the true nature of this quantization procedure. A
perturbative analysis of the classical system reveals the condition for the
stability of the classical system in terms of the existence of an anti-gravity
phase.

</DOC>
<DOC>
<DOCNO> 80685 </DOCNO>
Center Vortices at Strong Couplings and All Couplings


  Motivations for the center vortex theory of confinement are discussed. In
particular, it is noted that the abelian dual Meissner effect, which is the
signature of dual superconductivity, cannot adequately describe the confining
force at large distance scales. A long-range effective action is derived from
strong-coupling lattice gauge theory in D=3 dimensions, and it is shown that
center vortices emerge as the stable saddlepoints of this action. Thus, in the
case of strong couplings, the vortex picture is arrived at analytically. I also
respond briefly to a recent criticism regarding maximal center gauge.

</DOC>
<DOC>
<DOCNO> 101565 </DOCNO>
Processes with Long Memory: Regenerative Construction and Perfect


  We present a perfect simulation algorithm for stationary processes indexed by
Z, with summable memory decay. Depending on the decay, we construct the process
on finite or semi-infinite intervals, explicitly from an i.i.d. uniform
sequence. Even though the process has infinite memory, its value at time 0
depends only on a finite, but random, number of these uniform variables. The
algorithm is based on a recent regenerative construction of these measures by
Ferrari, Maass, Mart{\'\i}nez and Ney. As applications, we discuss the perfect
simulation of binary autoregressions and Markov chains on the unit interval.

</DOC>
<DOC>
<DOCNO> 100911 </DOCNO>
A Double Bounded Version of Schur's Partition Theorem


  Schur's partition theorem states that the number of partitions of n into
distinct parts congruent 1, 2 (mod 3) equals the number of partitions of n into
parts which differ by >= 3, where the inequality is strict if a part is a
multiple of 3. We establish a double bounded refined version of this theorem by
imposing one bound on the parts congruent 0,1 (mod 3) and another on the parts
congruent 2 (mod 3), and by keeping track of the number of parts in each of the
residue classes (mod 3). Despite the long history of Schur's theorem, our
result is new, and extends earlier work of Andrews, Alladi-Gordon and Bressoud.
We give combinatorial and q-theoretic proofs of our result. The special case
L=M leads to a representation of the generating function of the underlying
partitions in terms of the q-trinomial coefficients extending a similar
previous representation of Andrews.

</DOC>
<DOC>
<DOCNO> 84779 </DOCNO>
Comment about the Letter entitled ``Scalar fields as dark matter in


  In this comment we point out some problems with the approach used in the
paper "Scalar fields as dark matter in spiral galaxies" in the attempt to
explain the flatness of the rotation curves of galaxies.

</DOC>
<DOC>
<DOCNO> 11237 </DOCNO>
Delocalization of two interacting particles in a random potential:


  We consider a continuous one dimensional model of two charged interacting
particles in a random potential. The electric repulsion is strictly one
dimensional and it inhibits Anderson localization. In fact, the spectrum is
continuous. The case of electrical atraction is briefly studied and it shows
bounded states. So, the dynamics is sign dependent for this model. We support
our analytical results with numerical simulations where the effect of repulsion
breaking localization is clearly observed.

</DOC>
<DOC>
<DOCNO> 71712 </DOCNO>
Randall-Sundrum Phenomenology at Linear Colliders


  The physics of the Randall-Sundrum model relevant for future linear colliders
is briefly summarized. The differences between the case where Standard
Model(SM) fields are on the wall and where they are in the bulk are emphasized.

</DOC>
<DOC>
<DOCNO> 100247 </DOCNO>
Malliavin Calculus and Skorohod Integration for Quantum Stochastic


  A derivation operator and a divergence operator are defined on the algebra of
bounded operators on the symmetric Fock space over the complexification of a
real Hilbert space $\eufrak{h}$ and it is shown that they satisfy similar
properties as the derivation and divergence operator on the Wiener space over
$\eufrak{h}$. The derivation operator is then used to give sufficient
conditions for the existence of smooth Wigner densities for pairs of operators
satisfying the canonical commutation relations. For
$\eufrak{h}=L^2(\mathbb{R}_+)$, the divergence operator is shown to coincide
with the Hudson-Parthasarathy quantum stochastic integral for adapted
integrable processes and with the non-causal quantum stochastic integrals
defined by Lindsay and Belavkin for integrable processes.

</DOC>
<DOC>
<DOCNO> 151845 </DOCNO>
Condensates near the Argyres-Douglas point in SU(2) gauge theory with


  The behaviour of the chiral condensates in the SU(2) gauge theory with broken
N=2 supersymmetry is reviewed. The calculation of monopole, dyon, and charge
condensates is described. It is shown that the monopole and charge condensates
vanish at the Argyres-Douglas point where the monopole and charge vacua
collide. This phenomenon is interpreted as a deconfinement of electric and
magnetic charges at the Argyres-Douglas point.

</DOC>
<DOC>
<DOCNO> 174446 </DOCNO>
Search for the electric dipole excitations to the $3s_{1/2} \otimes


  The odd-mass $^{117}$Sn nucleus was investigated in nuclear resonance
fluorescence experiments up to an endpoint energy of the incident photon
spectrum of 4.1 MeV at the bremsstrahlung facility of the Stuttgart University.
More than 50 mainly hitherto unknown levels were found. From the measurement of
the scattering cross sections model independent absolute electric dipole
excitation strengths were extracted. The measured angular distributions
suggested the spins of 11 excited levels. Quasi-particle phonon model
calculations including a complete configuration space were performed for the
first time for a heavy odd-mass spherical nucleus. These calculations give a
clear insight in the fragmentation and distribution of the $E1$, $M1$, and $E2$
excitation strength in the low energy region. It is proven that the $1^{-}$
component of the two-phonon $[2^{+}_{1} \otimes 3^{-}_{1}]$ quintuplet built on
top of the $1/2^{+}$ ground state is strongly fragmented. The theoretical
calculations are consistent with the experimental data.

</DOC>
<DOC>
<DOCNO> 70024 </DOCNO>
Chiral Phase Transition within Effective Models with Constituent Quarks


  We investigate the chiral phase transition at nonzero temperature $T$ and
baryon-chemical potential $\mu_B$ within the framework of the linear sigma
model and the Nambu-Jona-Lasinio model. For small bare quark masses we find in
both models a smooth crossover transition for nonzero $T$ and $\mu_B=0$ and a
first order transition for T=0 and nonzero $\mu_B$. We calculate explicitly the
first order phase transition line and spinodal lines in the $(T,\mu_B)$ plane.
As expected they all end in a critical point. We find that, in the linear sigma
model, the sigma mass goes to zero at the critical point. This is in contrast
to the NJL model, where the sigma mass, as defined in the random phase
approximation, does not vanish. We also compute the adiabatic lines in the
$(T,\mu_B)$ plane. Within the models studied here, the critical point does not
serve as a ``focusing'' point in the adiabatic expansion.

</DOC>
<DOC>
<DOCNO> 152233 </DOCNO>
A note on the torsion dependence of D-brane RR couplings


  The dependence on the torsion H=db of the Wess-Zumino couplings of D-branes
that are trivially embedded in space-time is studied. We show that even in this
simple set-up some torsion components can be turned on, with a non-trivial
effect on the RR couplings. In the special cases in which either the tangent or
the normal bundle are trivial, the torsion dependence amounts to substitute the
standard curvature with its generalization in the presence of torsion, in the
usual couplings involving the roof genus A.

</DOC>
<DOC>
<DOCNO> 69217 </DOCNO>
Brane cosmological perturbations


  We address the question of cosmological perturbations in the context of brane
cosmology, where our Universe is a three-brane where matter is confined,
whereas gravity lives in a higher dimensional spacetime. The equations
governing the bulk perturbations are computed in the case of a general warped
universe. The results are then specialized to the case of a five-dimensional
spacetime, scenario which has recently attracted a lot of attention. In this
context, we decompose the perturbations into `scalar', `vector' and `tensor'
modes, which are familiar in the standard theory of cosmological perturbations.
The junction conditions, which relate the metric perturbations to the matter
perturbations in the brane, are then computed.

</DOC>
<DOC>
<DOCNO> 85342 </DOCNO>
Towards the solution of the relativistic gravitational radiation


  Here we present the results of applying the generalized Riemann zeta-function
regularization method to the gravitational radiation reaction problem. We
analyze in detail the headon collision of two nonspinning black holes with
extreme mass ratio. The resulting reaction force on the smaller hole is
repulsive. We discuss the possible extensions of these method to generic orbits
and spinning black holes. The determination of corrected trajectories allows to
add second perturbative corrections with the consequent increase in the
accuracy of computed waveforms.

</DOC>
<DOC>
<DOCNO> 68517 </DOCNO>
Charged Matter: Physics and Renormalisation


  Descriptions of the ground state in unbroken gauge theories with charged
particles are discussed. In particular it is shown that the on-shell Green's
functions and S-matrix elements corresponding to the scattering of these
variables in QED are free of soft and phase infra red divergences and that
these variables may be multiplicatively renormalised.

</DOC>
<DOC>
<DOCNO> 100886 </DOCNO>
The Combinatorial Gauss Diagram Formula for Kontsevich Integral


  In this paper, we shall give an explicit Gauss diagram formula for the
Kontsevich integral of links up to degree four. This practical formula enables
us to actually compute the Kontsevich integral in a combinatorial way.

</DOC>
<DOC>
<DOCNO> 8054 </DOCNO>
Central role of exchange-correlation hole in the 2D metal-insulator


  We show that the metal to insulator transition, whether generated by
decreasing the electron density or by increasing the spin alignment, is
determined by a universal functional form of the two-electron correlation
function g(r). This result provides direct evidence of the central role of the
Coulomb repulsion and exchange in driving the metal-insulator transition.

</DOC>
<DOC>
<DOCNO> 150489 </DOCNO>
IIB supergravity and various aspects of light-cone formalism in AdS


  Light-cone gauge manifestly supersymmetric formulation of type IIB
10-dimensional supergravity in $AdS_5 \times S^5$ background is discussed. The
formulation is given entirely in terms of light-cone scalar superfield,
allowing us to treat all component fields on an equal footing. Discrete energy
spectrum of field propagating in AdS space is explained within the framework of
light-cone approach. Light-cone gauge formulation of self-dual fields
propagating in AdS space is developed. An conjectured interrelation of higher
spin massless fields theory in AdS space-time and superstring theory in
Minkowski space is discussed.

</DOC>
<DOC>
<DOCNO> 117992 </DOCNO>
Erratum: Excitation Mechanism of Near-Infrared [Fe II] Emission in


  In the paper "Excitation Mechanism of Near-Infrared [Fe II] Emission in
Seyfert and Starburst Galaxies" by Hideaki Mouri, Kimiaki Kawara, and Yoshiaki
Taniguchi (ApJ, 528, 186 [2000]), the two panels of Figure 6 were printed into
different sizes, as the result of an error in the printing process. The correct
version of Figure 6 appears here.

</DOC>
<DOC>
<DOCNO> 12447 </DOCNO>
Hydrodynamics of crystals with interstitials


  The hydrodynamic equations for a crystals with interstitials, taking into
account the dissipative processes of the viscosity, heat conduction and the
interstitial diffusion are derived. To achieve that we use the phenomenological
approach has originally been applied in the theory of the superfluids for the
derivation of equations of the two-fluid hydrodynamics. On the basis of the
obtained equations the problem of the propagation of plane waves in the
crystals with low interstitial concentration has been considered. For the case
when effects of the viscosity and the heat conduction are absent and the
diffusion mobility of interstitials is small the absorption coefficient of
longitudinal sound wave has been calculated.

</DOC>
<DOC>
<DOCNO> 119345 </DOCNO>
A simple method of determining the Hubble constant


  Bidirectional relativistic proper motions of radio components of nearby
extragalactic sources give a strong constraint on the determination of the
Hubble constant $H_0$. Under the assumption that the real velocity of radio
components of extragalactic sources is not less than that of Galactic sources,
the value of $H_0$ can be estimated at a high level of accuracy. The assumption
is reasonable due to the general belief that the activity in the core of
galaxies must be more powerful than that of stars. This method is simple and
with only one uncertainty --- the real velocity of components. This uncertainty
is related to the value of the real velocity of componenets of Galactic sources
and the latter is always well-determined (note that the determination is
independent of $H_0$ and the distance of Galactic sources can be directly
measured at a rather high level of accuracy). Hopefully the method will play an
important role in future research to fix the value of $H_0$. With the data of
the three sources available so far and the assumption that the real velocity of
componenets of at least one of the sources is not less than a known velocity of
componenets of a Galactic source, the constant is estimated to be within
$27.08kms^{-1}Mpc^{-1} < H_0 \leq 53.15kms^{-1}Mpc^{-1}$ with this method.

</DOC>
<DOC>
<DOCNO> 7811 </DOCNO>
Magnetoconductivity of icosahedral and amorphous Al-Pd-Re films - a


  The magnetoconductivity of quasicrystals is often discussed in the frame of
quantum corrections, namely weak (anti-) localiza-tion and electron-electron
interaction. A premise for both effects is a strong elastic scattering of
conduction electrons. Amorphous and icosahedral phases are discussed as
Hume-Rothery alloys with an electronically induced structural peak at the
diameter of the Fermi sphere. Therefore, both should exhibit quantum
corrections. The preparation of quasicrystalline films via the amorphous route
offers the possibility to compare the magnetoconductivity on samples of
identical composition but different structure. We report on
magnetoconduc-tivity measurements at temperatures between 0.2 K and 22 K and
for magnetic fields up to 16 T. With the exception of the electronic diffusion
constant, amorphous as well as icosahedral Al-Pd-Re films can be described by
nearly the same set of parameters if the samples are well on the metallic side
of the metal-insulator transition.

</DOC>
<DOC>
<DOCNO> 151698 </DOCNO>
Casimir Force in Compact Noncommutative Extra Dimensions and Radius


  We compute the one loop Casimir energy of an interacting scalar field in a
compact noncommutative space of $R^{1,d}\times T^2_\theta$, where we have
ordinary flat $1+d$ dimensional Minkowski space and two dimensional
noncommuative torus. We find that next order correction due to the
noncommutativity still contributes an attractive force and thus will have a
quantum instability. However, the case of vector field in a periodic boundary
condition gives repulsive force for $d>5$ and we expect a stabilized radius.
This suggests a stabilization mechanism for a senario in Kaluza-Klein theory,
where some of the extra dimensions are noncommutative.

</DOC>
<DOC>
<DOCNO> 85376 </DOCNO>
Small strange stars and marginally stable orbit in Newtonian theory


  It is shown that for very rapidly rotating low mass strange stars the
marginally stable orbit is located above the stellar surface. This effect is
explained by the very important role of the oblateness of the rotating strange
star. The comparison with some ``academic'' examples is presented. This feature
is purely Newtonian in its nature and has nothing to do with relativistic
marginally stable orbit. The effect is very large and cannot be treated in a
perturbative way. It seems that strange stars as a very dense self-bound
objects are the only possibility in Nature to represent these toy models.

</DOC>
<DOC>
<DOCNO> 80991 </DOCNO>
Probability Distribution Function of the Diquark Condensate in Two


  We consider diquark condensation in finite density lattice SU(2). We first
present an extension of Vafa-Witten result, on spontaneous breaking of
vector-like global symmetries, that allows us to formulate a no-go theorem for
diquark condensation in a region of the chemical potential-mass parameter
space. We then describe a new technique to calculate diquark condensation at
any number of flavours directly at zero external source without using any
potentially dangerous extrapolation procedure. We apply it to the strong
coupling limit and find compelling evidences for a second order phase
transition, where a diquark condensate appears, as well as quantitative
agreement between lattice results and low-energy effective Lagrangian
calculations.

</DOC>
<DOC>
<DOCNO> 116464 </DOCNO>
Gravitational potential energy of simple bodies: the homogeneous


  Gravitational potential energy of the homogeneous bispherical concavo-convex
lens, with the equal absolute values of radii of curvature of both surfaces is
studied.

</DOC>
<DOC>
<DOCNO> 11836 </DOCNO>
A model for the atomic-scale structure of a dense, nonequilibrium fluid:


  It is shown that the equilibrium Generalized Mean Spherical Model of fluid
structure may be extended to nonequilibrium states with equation of state
information used in equilibrium replaced by an exact condition on the two-body
distribution function. The model is applied to the homogeneous cooling state of
granular fluids and upon comparison to molecular dynamics simulations is found
to provide an accurate picture of the pair distribution function.

</DOC>
<DOC>
<DOCNO> 119661 </DOCNO>
General relativistic treatment of the thermal, magnetic and rotational


  We investigate the thermal, magnetic and rotational evolution of isolated
neutron stars assuming that the dipolar magnetic field is confined to the
crust. Our treatment, for the first time, uses a fully general relativistic
formalism not only for the thermal but also for the magnetic part, and includes
partial general relativistic effects in the rotational part. Due to the fact
that the combined evolution depends crucially upon the compactness of the star,
three different equations of state have been employed in the calculations. In
the absence of general relativistic effects, while upon increasing compactness
a decrease of the crust thickness takes place leading into an accelerating
field decay, the inclusion of general relativistic effects intend to
``decelerate this acceleration''. As a consequence we find that within the
crustal field hypothesis, a given equation of state is compatible with the
observed periods $P$ and period derivative $\dot P$ provided the initial field
strength and current location as well as the magnitude of the impurity content
are constrained appropriately. Finally, we access the flexibility of the soft,
medium and stiff classes of equations of state as candidates in describing the
state of the matter in the neutron star interiors. The comparison of our model
calculations with observations, together with the consideration of independent
information about neutron star evolution, suggests that a not too soft equation
of state describes neutron star interiors and its cooling proceeds along the
`standard' scenario.

</DOC>
<DOC>
<DOCNO> 169662 </DOCNO>
Optimal States for Bell inequality Violations using Quadrature Phase


  We identify what ideal correlated photon number states are to required to
maximize the discrepancy between local realism and quantum mechanics when a
quadrature homodyne phase measurement is used. Various Bell inequality tests
are considered.

</DOC>
<DOC>
<DOCNO> 10701 </DOCNO>
Temperature-Dependence of the Resistivity of a Dilute 2D Electron System


  We report measurements of the resistance of silicon MOSFETs as a function of
temperature in high parallel magnetic fields where the 2D system of electrons
has been shown to be fully spin-polarized. A magnetic field suppresses the
metallic behavior observed in the absence of a magnetic field. In a field of
10.8 T, insulating behavior is found for densities up to n_s approximately 1.35
x 10^{11} cm^{-2} or 1.5 n_c; above this density the resistance is a very weak
function of temperature, varying less than 10% between 0.25 K and 1.90 K. At
low densities the resistance goes to infinity more rapidly as the temperature
is reduced than in zero field and the magnetoresistance diverges as T goes to
0.

</DOC>
<DOC>
<DOCNO> 83055 </DOCNO>
Why C++ is not very fit for GUI programming


  With no intent of starting a holy war, this paper lists several annoying C++
birthmarks that the author has come across developing GUI class libraries.
C++'s view of classes, instances and hierarchies appears tantalizingly close to
GUI concepts of controls, widgets, window classes and subwindows. OO models of
C++ and of a window system are however different. C++ was designed to be a
"static" language with a lexical name scoping, static type checking and
hierarchies defined at compile time. Screen objects on the other hand are
inherently dynamic; they usually live well beyond the procedure/block that
created them; the hierarchy of widgets is defined to a large extent by layout,
visibility and event flow. Many GUI fundamentals such as dynamic and geometric
hierarchies of windows and controls, broadcasting and percolation of events are
not supported directly by C++ syntax or execution semantics (or supported as
"exceptions" -- pun intended). Therefore these features have to be emulated in
C++ GUI code. This leads to duplication of a graphical toolkit or a window
manager functionality, code bloat, engaging in unsafe practices and forgoing of
many strong C++ features (like scoping rules and compile-time type checking).
This paper enumerates a few major C++/GUI sores and illustrates them on simple
examples.

</DOC>
<DOC>
<DOCNO> 101193 </DOCNO>
Norton's Trace Formulae for the Griess Algebra of a Vertex Operator


  Formulae expressing the trace of the composition of several (up to five)
adjoint actions of elements of the Griess algebra of a vertex operator algebra
are derived under certain assumptions on the action of the automorphism group.
They coincide, when applied to the moonshine module $V^\natural$, with the
trace formulae obtained in a different way by S.Norton, and the spectrum of
idempotents related to 2A, 2B, 3A and 4A element of the Monster is determined
by the representation theory of Virasoro algebra at $c=1/2$, $W_3$ algebra at
$c=4/5$ or $W_4$ algebra at $c=1$. The generalization to the trace function on
the whole space is also given for the composition of two adjoint actions, which
can be used to compute the McKay-Thompson series for a 2A involution of the
Monster.

</DOC>
<DOC>
<DOCNO> 100033 </DOCNO>
Bordism-finiteness and semi-simple group actions


  We give bordism-finiteness results for manifolds with semi-simple group
action. Consider the class of oriented manifolds which admit a circle action
with isolated fixed points such that the action extends to an $S^3$-action with
fixed point. We exhibit various subclasses, characterized by an upper bound for
the Euler characteristic and properties of the first Pontrjagin class, which
contain only finitely many oriented bordism types in any given dimension. Also
we show finiteness results for homotopy complex projective spaces and complete
intersections with $S^3$-action as above.

</DOC>
<DOC>
<DOCNO> 14124 </DOCNO>
Dielectric and Dilatometric Studies of Glass Transitions in Thin Polymer


  Dielectric relaxation and thermal expansion spectroscopy were made for thin
polystyrene films in order to measure the temperature $T_{\alpha}$
corresponding to the peak in the loss component of susceptibility due to the
$\alpha$-process and the $\alpha$-relaxation time $\tau$ as functions of film
thickness $d$. While the glass transition temperature $T_{\rm g}$ decreases
with decreasing film thickness, $T_{\alpha}$ and $\tau$ were found to remain
almost constant for $d>d_{\rm c}$ and decrease drastically for $d<d_{\rm c}$
for high temperatures. Here, $d_{\rm c}$ is a critical thickness. Near the
glass transition temperature, the thickness dependence of $T_{\alpha}$ and
$\tau$ is more prominent. The relation between the fragility index and
non-exponentiallity is discussed for thin films of polystyrene.

</DOC>
<DOC>
<DOCNO> 122297 </DOCNO>
Scattering in the inner accretion disk and the waveforms and


  The scattering by the inner accretion disk of X-ray radiation generated near
the surface of a spinning neutron star in a low-mass X-ray binary (LMXB) has
observable effects on the waveforms of millisecond X-ray flux oscillations
produced e.g. during type-I bursts or in the millisecond pulsar SAX
J1808.4--3658. We study these effects in the framework of a simplified model in
which there is a single emitting spot on the stellar surface, which is visible
both directly and in X-rays scattered from the disk. The main signature of
scattering from a thin disk is that the pulse of scattered flux leads (if the
star rotates in the same sense as the disk) or lags (in the contrary case) the
primary pulse of direct emission by a quarter of a spin cycle. This is caused
by Doppler boosting of radiation in the sub-relativistic Keplerian flow. The
disk-scattered flux is revealed better in energy-resolved waveforms and the
phase dependence of the polarized flux component. The phenomenon discussed
permits direct testing of the presence of standard thin disks near the neutron
stars in LMXBs and should be observable with future X-ray timing experiments
having a few times better sensitivity than RXTE and also with sensitive X-ray
polarimeters.

</DOC>
<DOC>
<DOCNO> 12063 </DOCNO>
Phase Behavior of a Simple Model for Membrane Proteins


  We report a numerical simulation of the phase diagram of a simple model for
membrane proteins constrained to move in a plane. In analogy with the
corresponding three dimensional models, the liquid-gas transition becomes
metastable as the range of attraction decreases. Spontaneous crystallization
happens much more readily in the two dimensional models rather than in their
three dimensional counterparts.

</DOC>
<DOC>
<DOCNO> 122464 </DOCNO>
Origin of Cosmic Radiation


  I give a brief overview of cosmic ray physics, highlighting some key
questions and how they will be addressed by new experiments.

</DOC>
<DOC>
<DOCNO> 11805 </DOCNO>
Osmotic Properties of Charged Cylinders: Critical Evaluation of


  The osmotic coefficient of B-DNA in water may, in moderately dilute
solutions, deviate as much as 100 % from predictions based on a simple
'counterion condensation' theory. We determine the results for osmotic
properties via a cell model description of the ionic atmosphere near a
cylindrical polyelectrolyte. The cell model predictions for the osmotic
properties disagree with predictions based on simple condensation theory, but
are in surprisingly good harmony with experimental findings. We argue that the
neglect of finite-radius effects makes simple condensation theory inapplicable
at all but impractically low polyelectrolyte concentrations and, unable to
reproduce osmotic properties of polyelectrolytes such as DNA.

</DOC>
<DOC>
<DOCNO> 122246 </DOCNO>
Buoyant radio plasma in clusters of galaxies


  Radio galaxies are known to inflate lobes of hot relativistic plasmas into
the intergalactic medium. Here we present hydrodynamical and
magnetohydrodynamical simulations of these hot plasma bubbles in FRII objects.
We focus on the later stages of their evolution after the jet has died down and
after the bow shock that surrounded the lobes at earlier stages has vanished.
We investigate the evolution of the plasma bubbles as they become subject to
Rayleigh-Taylor instabilities. From our simulations we calculate the radio and
X-ray emissivities of the bubbles and discuss their appearance in observations.
Finally, we investigate the influence of large-scale magnetic fields on the
evolution of the bubbles. The issues of re-acceleration and diffusion of
relativistic particles are briefly discussed.

</DOC>
<DOC>
<DOCNO> 118080 </DOCNO>
On the particle acceleration near the light surface of radio pulsars


  The two-fluid effects on the radial outflow of relativistic electron-positron
plasma are considered. It is shown that for large enough Michel magnetization
parameter (1969) and multiplication parameter, the one-fluid MHD approximation
remains correct in the whole region where |E| < |B|. In the case in which the
longitudinal electric current is smaller than the Goldreich-Julian one, the
acceleration of particles is determined near the light surface where |E| = |B|.
 It is shown that, as in the previously considered cylindrical geometry
(Beskin, Gurevich & Istomin 1983), almost all electromagnetic energy is
transformed into the energy of particles in the narrow boundary layer. The
relative thickness of this layer is shown to be of the order of the inverse of
multiplication parameter.

</DOC>
<DOC>
<DOCNO> 12191 </DOCNO>
Communication in networks with hierarchical branching


  We present a simple model of communication in networks with hierarchical
branching. We analyze the behavior of the model from the viewpoint of critical
systems under different situations. For certain values of the parameters, a
continuous phase transition between a sparse and a congested regime is observed
and accurately described by an order parameter and the power spectra. At the
critical point the behavior of the model is totally independent of the number
of hierarchical levels. Also scaling properties are observed when the size of
the system varies. The presence of noise in the communication is shown to break
the transition. Despite the simplicity of the model, the analytical results are
a useful guide to forecast the main features of real networks.

</DOC>
<DOC>
<DOCNO> 118279 </DOCNO>
Observed Smooth Energy is Anthropically Even More Likely As Quintessence


  For a universe presently dominated by static or dynamic vacuum energy,
cosmological constant (LCDM) or quintessence (QCDM), we calculate the
asymptotic collapsed mass fraction as function of the present ratio of vacuum
energy to clustered mass, \Omega_{Q0}/\Omega_{m0}. Identifying these collapsed
fractions as anthropic probabilities, we find the value \Omega_{Q0}/\Omega_{m0}
\sim 2 to be reasonably likely in LCDM, and very likely in QCDM.

</DOC>
<DOC>
<DOCNO> 119209 </DOCNO>
A Uniform Analysis of the Ly-alpha forest at z = 0 - 5: I. The sample


  We present moderate resolution data for 39 QSOs at z $\approx$ 2 obtained at
the Multiple Mirror Telescope. These data are combined with spectra of
comparable resolution of 60 QSOs with redshifts greater than 1.7 found in the
literature to investigate the distribution of Ly-alpha forest lines in redshift
and equivalent width. We find a value for $\gamma$, the parameter describing
the number distribution of Ly-alpha forest lines in redshift, of $1.88\pm0.22$
for lines stronger than a rest equivalent width of 0.32 $\AA$, in good
agreement with some previous studies. The Kolmogorov-Smirnov test was applied
to the data and it is found that this single power law is a good fit over the
relevant redshift ranges. Simulations of the Lyman alpha forest were performed
to determine the completeness of the line lists and to test how well the
analysis the underlying line statistics, given this level of completeness.

</DOC>
<DOC>
<DOCNO> 152020 </DOCNO>
On the Structure of Noncommutative N=2 Super Yang-Mills Theory


  We show that the recently proposed formulation of noncommutative N=2 Super
Yang-Mills theory implies that the commutative and noncommutative effective
coupling constants \tau(u) and \tau_{nc}(u) coincide. We then introduce a key
relation which allows to find a nontrivial solution of such equation, thus
fixing the form of the low-energy effective action. The dependence on the
noncommutative parameter arises from a rational function deforming the
Seiberg-Witten differential.

</DOC>
<DOC>
<DOCNO> 120283 </DOCNO>
The BeppoSAX view of the Galactic Center region


  The Galactic Center Region has been surveyed in 1997-1998 with the Narrow
Field Instruments on-board the BeppoSAX satellite (2-10keV energy range). The
X-ray emission from SgrA*, the putative supermassive black hole at the center
of our Galaxy, has been measured and its spectrum studied, together with the
X-ray emission from several bright X-ray sources, LMXBs containing neutron
stars and black holes located within the region ($|l|<2\deg)\times(|b|<1\deg$).
New point-like X-ray sources have also been discovered. The results on the
diffuse emission coming from the SgrA Complex are summarized here: it displays
a two-temperature thermal spectrum (kT1~0.6keV and kT2~8keV) and an
energy-dependent morphology, with the hard emission (5-10 keV) elongated along
the galactic plane and the soft one (2-5 keV) spatially correlated with the
radio halo of SgrAEast. The results of the study of the diffuse X-ray emission
from other three fields in the Galactic Center Region containing the giant
molecular clouds SgrB2, SgrC and SgrD are reported for the first time. The
diffuse emission from the direction of these three molecular clouds shows a
double temperature nature as well, with a prominent iron line at \~6.7keV, the
intensity and equivalent width of which depends on the galactic longitude.
Moreover, the SgrB2 spectrum shows an intense 6.4keV line of fluorescent
origin. While the hard component of the Galactic Center diffuse emission
displays a similar temperature with respect to the Galactic Ridge, the low
temperature plasma is significantly softer. This may be due to a net
contribution produced from the accretion of material onto old isolated neutron
stars located inside the giant molecular clouds.

</DOC>
<DOC>
<DOCNO> 12154 </DOCNO>
Hamiltonian theory of gaps, masses and polarization in quantum Hall


  I furnish details of the hamiltonian theory of the FQHE developed with Murthy
for the infrared, which I subsequently extended to all distances and apply it
to Jain fractions \nu = p/(2ps + 1). The explicit operator description in terms
of the CF allows one to answer quantitative and qualitative issues, some of
which cannot even be posed otherwise. I compute activation gaps for several
potentials, exhibit their particle hole symmetry, the profiles of charge
density in states with a quasiparticles or hole, (all in closed form) and
compare to results from trial wavefunctions and exact diagonalization. The
Hartree-Fock approximation is used since much of the nonperturbative physics is
built in at tree level. I compare the gaps to experiment and comment on the
rough equality of normalized masses near half and quarter filling. I compute
the critical fields at which the Hall system will jump from one quantized value
of polarization to another, and the polarization and relaxation rates for half
filling as a function of temperature and propose a Korringa like law. After
providing some plausibility arguments, I explore the possibility of describing
several magnetic phenomena in dirty systems with an effective potential, by
extracting a free parameter describing the potential from one data point and
then using it to predict all the others from that sample. This works to the
accuracy typical of this theory (10 -20 percent). I explain why the CF behaves
like free particle in some magnetic experiments when it is not, what exactly
the CF is made of, what one means by its dipole moment, and how the comparison
of theory to experiment must be modified to fit the peculiarities of the
quantized Hall problem.

</DOC>
<DOC>
<DOCNO> 10858 </DOCNO>
Statistical Mechanics of Recurrent Neural Networks I. Statics


  A lecture notes style review of the equilibrium statistical mechanics of
recurrent neural networks with discrete and continuous neurons (e.g. Ising,
coupled-oscillators). To be published in the Handbook of Biological Physics
(North-Holland). Accompanied by a similar review (part II) dealing with the
dynamics.

</DOC>
<DOC>
<DOCNO> 68554 </DOCNO>
Proposal for a Constant Cosmological Constant


  It is proposed that the apparent positive acceleration of the cosmological
scale factor is due to the vacuum energy of an incomplete chiral phase
transition in a hidden SU(2) sector. Constraints from primordial
nucleosynthesis imply that the present metastable phase is in a substantially
supercooled state. It is argued that massless chiral condensates can
substantially enhance the possibility of supercooling, and a linear sigma model
exhibiting scale invariance broken only at the quantum level is shown to
accommodate the required supercooling with a reasonable choice of quartic
couplings. The extensive supercooling can in principle be confirmed or rejected
on the basis of interface tension measurements in lattice simulations with
dynamical fermions.

</DOC>
<DOC>
<DOCNO> 13522 </DOCNO>
Spin Excitations in Localized and Itinerant Magnets


  Collective excitations in magnetic materials can be investigated by means of
inelastic neutron scattering. We show that this experimental method gives
access to the complete spectrum of magnetic fluctuations through the energy-
and momentum-dependence of the dynamical susceptibility. We focus on the
dynamical properties of magnets with localized spin densities and of metals.
  From such studies, microscopic parameters like exchange integrals, spin-wave
stiffness and relaxation times can be determined. This is of great help to test
current theories in magnetism.

</DOC>
<DOC>
<DOCNO> 100684 </DOCNO>
On commuting and non-commuting complexes


  In this paper we study various simplicial complexes associated to the
commutative structure of a finite group G. We define NC(G) (resp. C(G)) as the
complex associated to the poset of pairwise non-commuting (resp. commuting)
sets in G.
  We observe that NC(G) has only one positive dimensional connected component,
which we call BNC(G), and we prove that BNC(G) is simply connected.
  Our main result is a simplicial decomposition formula for BNC(G) which
follows from a result of A. Bjorner, M. Wachs and V. Welker on inflated
simplicial complexes. As a corollary, we obtain that if G has a nontrivial
center or if G has odd order, then the homology group H_{n-1}(BNC(G)) is
nontrivial for every n such that G has a maximal noncommuting set of order n.

</DOC>
<DOC>
<DOCNO> 101389 </DOCNO>
Remarks on the Schur-Howe-Sergeev Duality


  We establish a new Howe duality between a pair of two queer Lie superalgebras
(q(m),q(n)). This gives a representation theoretic interpretation of a
well-known combinatorial identity for Schur Q-functions. We further establish
the equivalence between this new Howe duality and the Schur-Sergeev duality
between q(n) and a central extension $\Hy_k$ of the hyperoctahedral group H_k.
We show that the zero-weight space of a q(n)-module with highest weight
$\lambda$ given by a strict partition of n is an irreducible module over the
finite group $\Hy_n$ parameterized by $\lambda$. We also discuss some
consequences of this Howe duality.

</DOC>
<DOC>
<DOCNO> 11994 </DOCNO>
Effects of Next-Nearest-Neighbor Repulsion on One-Dimensional


  We examine effects of the next-nearest-neighbor repulsion on electronic
states of a one-dimensional interacting electron system which consists of
quarter-filled band and interactions of on-site and nearest-neighbor repulsion.
We derive the effective Hamiltonian for the electrons around wave number $\pm
\kf$ ($\kf$: Fermi wave number) and apply the renormalization group method to
the bosonized Hamiltonian. It is shown that the next-nearest-neighbor repulsion
makes $4\kf$-charge ordering unstable and suppresses the spin fluctuation.
Further the excitation gaps and spin susceptibility are also evaluated.

</DOC>
<DOC>
<DOCNO> 151140 </DOCNO>
Matroid Theory and Chern-Simons


  It is shown that matroid theory may provide a natural mathematical framework
for a duality symmetries not only for quantum Yang-Mills physics, but also for
M-theory. Our discussion is focused in an action consisting purely of the
Chern-Simons term, but in principle the main ideas can be applied beyond such
an action. In our treatment the theorem due to Thistlethwaite, which gives a
relationship between the Tutte polynomial for graphs and Jones polynomial for
alternating knots and links, plays a central role. Before addressing this
question we briefly mention some important aspects of matroid theory and we
point out a connection between the Fano matroid and D=11 supergravity. Our
approach also seems to be related to loop solutions of quantum gravity based in
Ashtekar formalism.

</DOC>
<DOC>
<DOCNO> 80639 </DOCNO>
Comment on hep-lat/9901005 v1-v3 by W. Bietenholz


  I comment on the above paper(s) discussing the issue of non-ultralocality for
Ginsparg-Wilson fermionic actions. The purpose of this note is to point out
that the new claim in "v3" (Feb 24, 2000), alleging the proof for "all
Ginsparg-Wilson fermions", might not be substantiated. The remarkable evolution
of versions of this paper is put in context with the literature existing at the
time of their appearance.

</DOC>
<DOC>
<DOCNO> 117260 </DOCNO>
Dependence of the Energy of Molecules on Interatomic Distance at Large


  Earlier it has been supposed that energy of molecules depends on interatomic
distance according to the curve 1, Fig. 1. However, dissociation of molecules
(for example, Te2=2Te) often is a chemical reaction. According to chemical
kinetics, chemical reactions overcome a potential barrier. This barrier is
absent at the curve 1. It is a very strong argument against the curve 1. It has
been shown that the molecule energy dependence on interatomic distance can
behave at large distances not so but like the curve 2, Fig. 1. Earlier it has
been supposed that quantum chemical methods give a wrong result at big
distances if the wave function does not turn to zero. In this paper it has been
shown that it must not turn to zero.

</DOC>
<DOC>
<DOCNO> 151826 </DOCNO>
IIA/B, Wound and Wrapped


  We examine the T-duality relation between 1+1 NCOS and the DLCQ limit of type
IIA string theory. We show that, as long as there is a compact dimension, one
can meaningfully define an `NCOS' limit of IIB/A string theory even in the
absence of D-branes (and even if there is no B-field). This yields a theory of
closed strings with strictly positive winding, which is T-dual to DLCQ IIA/B
without any D-branes. We call this the Type IIB/A Wound String Theory. The
existence of decoupled sectors can be seen directly from the energy spectrum,
and mirrors that of the DLCQ theory. It becomes clear then that all of the
different p+1 NCOS theories are simply different states of this single Wound
IIA/B theory which contain D-branes. We study some of the properties of this
theory. In particular, we show that upon toroidal compactification, Wound
string theory is U-dual to various Wrapped Brane theories which contain OM
theory and the ODp theories as special states.

</DOC>
<DOC>
<DOCNO> 11772 </DOCNO>
Short-range polaron correlations in the ferromagnetic La(1-x)Ca(x)MnO(3)


  We use neutron scattering to demonstrate the presence of lattice polarons and
their short-range correlations for several samples of La$_{1-x}$Ca$_x$MnO$_3$
in the Ca doping range $0.15\leq x\leq 0.3$. We establish the doping dependence
of the orientation, commensuration, and coherence length of the polaron
correlations and show that the populations of correlated and uncorrelated
polarons are intimately related to the transport properties of the materials.

</DOC>
<DOC>
<DOCNO> 71107 </DOCNO>
Quarks in nuclear medium


  Using the quark-meson coupling (QMC) model we study nuclear matter from the
point of view of quark degrees of freedom. As the nucleon model we adopt the
MIT bag model and the relativistic constituent quark model, where a square well
and harmonic oscillator potentials are used to confine the quarks. We introduce
the Lorentz-vector type confining potential as well as the Lorentz-scalar type
one in order to examine how the vector confining potential contributes to the
properties of the nucleon and nuclear matter. Next, we perform a re-definition
of the scalar field in matter and transform the QMC model to a QHD-type model
with a non-linear scalar potential. The result obtained from QMC is then
compared with the potentials which are determined so as to fit various
properties of finite nuclei and nuclear matter in relativistic mean-field
models. The QMC model provides the parameters $\kappa \sim 20 - 40$ (fm$^{-1}$)
and $\lambda \sim 80 - 400$ for the standard, non-linear scalar potential. We
discuss a relationship between the QMC and QHD-type models in detail.

</DOC>
<DOC>
<DOCNO> 10107 </DOCNO>
Ground State Entropy of the Potts Antiferromagnet with


  We present exact calculations of the zero-temperature partition function
(chromatic polynomial) and $W(q)$, the exponent of the ground-state entropy,
for the $q$-state Potts antiferromagnet with next-nearest-neighbor spin-spin
couplings on square lattice strips, of width $L_y=3$ and $L_y=4$ vertices and
arbitrarily great length $L_x$ vertices, with both free and periodic boundary
conditions. The resultant values of $W$ for a range of physical $q$ values are
compared with each other and with the values for the full 2D lattice. These
results give insight into the effect of such non-nearest neighbor couplings on
the ground state entropy. We show that the $q=2$ (Ising) and $q=4$ Potts
antiferromagnets have zero-temperature critical points on the $L_x \to \infty$
limits of the strips that we study. With the generalization of $q$ from
${\mathbb Z}_+$ to ${\mathbb C}$, we determine the analytic structure of $W(q)$
in the $q$ plane for the various cases.

</DOC>
<DOC>
<DOCNO> 8145 </DOCNO>
Amplitude of Aharonov-Bohm oscillations in mesoscopic metallic rings as


  We report measurements of the amplitude of the Aharonov-Bohm oscillations in
a mesoscopic diffusive gold ring as a function of the DC bias voltage V. The
amplitude of the h/e oscillations increases with V once the Thouless energy Ec
and thermal energy are exceeded, and decreases at higher values of V. The
increase of the amplitude is interpreted in terms of a superposition of the
statistically independent contributions of eV/Ec energy intervals, whereas its
decrease at high V could be attributed to enhanced inelastic scattering
processes.

</DOC>
<DOC>
<DOCNO> 118498 </DOCNO>
Tests of Statistical Methods for Estimating Galaxy Luminosity Function


  We studied the statistical methods for the estimation of the luminosity
function (LF) of galaxies. We focused on four nonparametric estimators:
$1/V_{\rm max}$ estimator, maximum-likelihood estimator of Efstathiou et al.
(1988), Cho{\l}oniewski's estimator, and improved Lynden-Bell's estimator. The
performance of the $1/V_{\rm max}$ estimator has been recently questioned,
especially for the faint-end estimation of the LF. We improved these estimators
for the studies of the distant Universe, and examined their performances for
various classes of functional forms by Monte Carlo simulations. We also applied
these estimation methods to the mock 2dF redshift survey catalog prepared by
Cole et al. (1998). We found that $1/V_{\rm max}$ estimator yields a completely
unbiased result if there is no inhomogeneity, but is not robust against
clusters or voids. This is consistent with the well-known results, and we did
not confirm the bias trend of $1/V_{\rm max}$ estimator claimed by Willmer
(1997) in the case of homogeneous sample. We also found that the other three
maximum-likelihood type estimators are quite robust and give consistent results
with each other. In practice we recommend Cho{\l}oniewski's estimator for two
reasons: 1. it simultaneously provides the shape and normalization of the LF;
2. it is the fastest among these four estimators, because of the algorithmic
simplicity. Then, we analyzed the photometric redshift data of the Hubble Deep
Field prepared by Fern\'{a}ndez-Soto et al. (1999) using the above four
methods. We also derived luminosity density $\rho_{\rm L}$ at $B$- and
$I$-band. Our $B$-band estimation is roughly consistent with that of Sawicki,
Lin, & Yee (1997), but a few times lower at $2.0 < z < 3.0$. The evolution of
$\rho_{\rm L}(I)$ is found to be less prominent.

</DOC>
<DOC>
<DOCNO> 119608 </DOCNO>
Five High-Redshift Quasars Discovered in Commissioning Imaging Data of


  We report the discovery of five quasars with redshifts of 4.67 - 5.27 and
z'-band magnitudes of 19.5-20.7 M_B ~ -27. All were originally selected as
distant quasar candidates in optical/near-infrared photometry from the Sloan
Digital Sky Survey (SDSS), and most were confirmed as probable high-redshift
quasars by supplementing the SDSS data with J and K measurements. The quasars
possess strong, broad Lyman-alpha emission lines, with the characteristic sharp
cutoff on the blue side produced by Lyman-alpha forest absorption. Three
quasars contain strong, broad absorption features, and one of them exhibits
very strong N V emission. The amount of absorption produced by the Lyman-alpha
forest increases toward higher redshift, and that in the z=5.27 object (D_A ~
0.7) is consistent with a smooth extrapolation of the absorption seen in lower
redshift quasars. The high luminosity of these objects relative to most other
known objects at z >~ 5 makes them potentially valuable as probes of early
quasar properties and of the intervening intergalactic medium.

</DOC>
<DOC>
<DOCNO> 85031 </DOCNO>
Gravitational instabilities in helicity-1 waves propagating through


  It is shown that the interaction of helicity-1 waves of gravity and matter in
a thin slab configuration produces new types of instabilities. Indeed, a
transverse spin-2 helicity-1 mode interacts strongly with the shear motion of
matter. This mode is unstable above a critical wavelength which reminds the
Jeans wavelength but with the speed of sound interchanged by the speed of
light. The two instabilities are of course different. For the case analyzed, a
plane parallel configuration, Jeans instability appears through a density wave
perturbation, the material collapsing into a set of plane-parallel slabs. On
the other hand, the helicity-1 wave instability induces a transverse motion in
the fluid that tends to shear in the material along the node of the
perturbation.

</DOC>
<DOC>
<DOCNO> 84909 </DOCNO>
A Plane-Symmetric Gravitational Field as a Generalized Nonlinear Sigma


  The Einstein equations for a plane-symmetric gravitational field coupled to
an arbitrary nonlinear sigma model (NSM) are shown to be represented in the
form of dynamical equations of a {\it generalized effective NSM}. The
gravitational equations are studied in this case by the methods of analyzing
NSM equations. In the case of a two-component diagonal NSM exact solutions are
found by the functional parameter method.

</DOC>
<DOC>
<DOCNO> 12730 </DOCNO>
"Go with the winners"-Simulations


  We describe a general strategy for sampling configurations from a given
(Gibbs-Boltzmann or other) distribution. It is {\it not} based on the
Metropolis concept of establishing a Markov process whose stationary state is
the wanted distribution. Instead, it builds weighted instances according to a
biased distribution. If the bias is optimal, all weights are equal and
importance sampling is perfect. If not, "population control" is applied by
cloning/killing configurations with too high/low weight. It uses the fact that
nontrivial problems in statistical physics are high dimensional. Therefore,
instances are built up in many steps, and the final weight can be guessed at an
early stage. In contrast to evolutionary algorithms, the cloning/killing is
done such that the wanted distribution is strictly observed without
simultaneously keeping a large population in computer memory. We apply this
method (which is also closely related to diffusion type quantum Monte Carlo) to
several problems of polymer statistics, population dynamics, and percolation.

</DOC>
<DOC>
<DOCNO> 84939 </DOCNO>
Spin-1/2 Particles in Non-Inertial Reference Frames: Low- and


  Spin-1/2 particles can be used to study inertial and gravitational effects by
means of interferometers, particle accelerators, and ultimately quantum
systems. These studies require, in general, knowledge of the Hamiltonian and of
the inertial and gravitational quantum phases. The procedure followed gives
both in the low- and high-energy approximations. The latter affords a more
consistent treatment of mass at high energies. The procedure is based on
general relativity and on a solution of the Dirac equation that is exact to
first-order in the metric deviation. Several previously known acceleration and
rotation induced effects are re-derived in a comprehensive, unified way.
Several new effects involve spin, electromagnetic and inertial/gravitational
fields in different combinations.

</DOC>
<DOC>
<DOCNO> 121427 </DOCNO>
Diffraction-limited bispectrum speckle interferometry and speckle


  We present bispectrum speckle interferometry and speckle polarimetry of the
deeply embedded infrared bipolar outflow source S140 IRS1, a massive
protostellar object in the L1204 molecular cloud. Using the SAO 6 m telescope,
we obtained 280 mas resolution polarization maps of S140 IRS1 as well as a
K-band image with diffraction-limited resolution lambda/D of 76 mas, which is
the highest angular resolution image of a young outflow source ever obtained in
the infrared. Our data suggest that the central source is marginally resolved
with a FWHM diameter of approximately 20 mas (~ 20 AU). The most remarkable
feature in our image is a bright extended and very clumpy structure pointing
away from the central source in exactly the same direction as the blue-shifted
CO outflow lobe. A centro-symmetric pattern of high polarization in this
feature suggests that we see scattered light from the central source. We
interprete this feature as the clumpy inner surface of a partially evacuated
cavity in the circumstellar envelope around IRS1, which has been excavated by
the strong outflow from IRS1.

</DOC>
<DOC>
<DOCNO> 13656 </DOCNO>
Effect of nonmagnetic impurities on stripes in high-Tc cuprates


  We perform the numerically exact diagonalization study of the t-J model with
nonmagnetic impurities to clarify the relation between Zn impurities and the
stripes. By examining the hole-hole correlation function for a two-hole
\sqrt{18}x\sqrt{18} cluster with a single impurity, we find that the impurity
has a tendency to stabilize vertical charge stripes. This tendency is caused by
the gain of the kinetic energy of holes moving along the stripes that are
formed avoiding the impurity.

</DOC>
<DOC>
<DOCNO> 85082 </DOCNO>
On the local structure of the Klein-Gordon field on curved spacetimes


  This paper investigates wave-equations on spacetimes with a metric which is
locally analytic in the time. We use recent results in the theory of the
non-characteristic Cauchy problem to show that a solution to a wave-equation
vanishing in an open set vanishes in the ``envelope'' of this set, which may be
considerably larger and in the case of timelike tubes may even coincide with
the spacetime itself. We apply this result to the real scalar field on a
globally hyperbolic spacetime and show that the field algebra of an open set
and its envelope coincide. As an example there holds an analog of Borchers'
timelike tube theorem for such scalar fields and hence, algebras associated
with world lines can be explicitly given. Our result applies to cosmologically
relevant spacetimes.

</DOC>
<DOC>
<DOCNO> 40363 </DOCNO>
Search for Susy with Missing Transverse Energy and Jets at CDF


  Events with signatures involving large missing transverse energy (MET) are
among the quintessential search modes for R-parity conserving supersymmetry.
CDF has conducted two recent analyses for supersymmetry which use MET and jets.
The MET and monojet signature is employed to determine process independent
limits for the production of new physics beyond the Standard Model and then
applied to models of spontaneous breaking of supersymmetry to determine limits
on the supersymmetry breaking parameter and the gravitino mass. Direct searches
for scalar top and scalar bottom quarks within the framework of supersymmetric
models are performed using a signature of MET and two heavy flavor jets. Since
the data is found to be consistent with Standard Model expectations, limits are
determined in the mass planes $m (\tilde{\chi}_{1}^{0}) - m (\tilde{t}_{1})$
and $m (\tilde{\chi}_{1}^{0}) - m (\tilde{b}_{1})$.

</DOC>
<DOC>
<DOCNO> 9126 </DOCNO>
Nonlinear ac susceptibility studies of high-$T_c$ rings: Influence of


  We have studied the influence of the patterning procedure on the critical
current density of high-$T_c$ YBa$_2$Cu$_3$O$_{7-\delta}$ thin rings using the
nonlinear ac susceptibility method. At no applied dc magnetic field we have
found that laser ablation degrades strongly the critical current density
whereas ion beam etching has only a weak influence on it. From the measurements
at different frequencies and dc magnetic fields we analyzed the influence of
flux creep and obtained the field dependence of the flux creep exponent. Our
data reconfirm the recently observed scaling relation for the nonlinear
susceptibility response of type-II superconductors.

</DOC>
<DOC>
<DOCNO> 10993 </DOCNO>
Adsorption and collapse transitions of a linear polymer chain


  We study the problem of adsorption and collapse transition of a linear
polymer chain situated in a fractal container represented by a 4-simplex
lattice and interacting with a surface adsorbed linear polymer chain. The
adsorbed chain monomers act as pinning sites for the polymer chain. This
problem has been solved exactly using real space renormalization group
transformation. The resulting phase diagram and critical exponents are given.

</DOC>
<DOC>
<DOCNO> 117584 </DOCNO>
Probing the Cosmic Dark Age in X-rays


  Empirical studies of the first generation of stars and quasars will likely
become feasible within the next decade in several different wavelength bands.
Microwave anisotropy experiments, such as MAP or Planck, will set constraints
on the ionization history of the intergalactic medium due to these sources. In
the infrared, the Next Generation Space Telescope (NGST) will be able to
directly detect sub-galactic objects at redshifts z>10. In the optical, data
from the Hubble Deep Field already places a constraint on the abundance of
high-redshift quasars. However, the epoch of the first quasars might be first
probed in X-ray bands, by instruments such as the Chandra X-ray Observatory
(CXO) and the X-ray Multi-mirror Mission (XMM). In a 500 Ksec integration, CXO
reaches a sensitivity of 2x10-16 erg/s cm^2. Based on simple hierarchical CDM
models, we find that at this flux threshold approx. 100 quasars might be
detectable from redshifts z>5, and approx. 1 quasar at z=10, in each 17x17
arcmin field. Measurement of the power spectrum of the unresolved soft X-ray
background will further constrain models of faint, high-redshift quasars.

</DOC>
<DOC>
<DOCNO> 151583 </DOCNO>
Comment on Ambiguities in the Holographic Weyl Anomaly


  We consider possible ambiguities in the holographic Weyl anomaly that are
caused by local terms in the flow equation. We point out that such ambiguities
actually do not give physically meaningful contributions to the Weyl anomaly.

</DOC>
<DOC>
<DOCNO> 84730 </DOCNO>
Low Frequency Gravitational Waves from White Dwarf MACHO Binaries


  The possibility that Galactic halo MACHOs are white dwarfs has recently
attracted much attention. Using the known properties of white dwarf binaries in
the Galactic disk as a model, we estimate the possible contribution of halo
white dwarf binaries to the low-frequency (10^{-5} Hz} < f < 10^{-1}Hz)
gravitational wave background. Assuming the fraction of white dwarfs in
binaries is the same in the halo as in the disk, we find the confusion
background from halo white dwarf binaries could be five times stronger than the
expected contribution from Galactic disk binaries, dominating the response of
the proposed space based interferometer LISA. Low-frequency gravitational wave
observations will be the key to discovering the nature of the dark MACHO binary
population.

</DOC>
<DOC>
<DOCNO> 120038 </DOCNO>
The ORFEUS II Echelle Spectrometer: Instrument description, performance


  During the second flight of the ORFEUS-SPAS mission in November/December
1996, the Echelle spectrometer was used extensively by the Principal and Guest
Investigator teams as one of the two focal plane instruments of the ORFEUS
telescope. We present the in-flight performance and the principles of the data
reduction for this instrument. The wavelength range is 90 nm to 140 nm, the
spectral resolution is significantly better than lambda/(Delta lambda) = 10000,
where Delta lambda is measured as FWHM of the instrumental profile. The
effective area peaks at 1.3 cm^2 near 110 nm. The background is dominated by
straylight from the Echelle grating and is about 15% in an extracted spectrum
for spectra with a rather flat continuum. The internal accuracy of the
wavelength calibration is better than +/- 0.005 nm.

</DOC>
<DOC>
<DOCNO> 152371 </DOCNO>
Renormalization of non-locally regularized BRST-anti-BRST theories


  An extension of the non-local regularization scheme is formulated in the
Sp(2) symmetric Lagrangian BRST quantization framework. It generates a
systematic treatment of the anomalous quantum master equations and allows to
substract the divergences as well as to calculate genuine higher loop BRST and
anti-BRST anomalies.

</DOC>
<DOC>
<DOCNO> 69965 </DOCNO>
Inflaton Particles in Reheating


  In many theories of reheating starting from the classical spatially
homogeneous inflaton field, its accompanying inhomogeneous part (which arises
from primordial quantum fluctuations) is treated as a first order perturbation.
We examine some consequences of treating it non-perturbatively in a model where
a first order treatment is invalid. In particular we consider effects on the
long-wavelength curvature parameter relevant to the cosmic microwave background
fluctuations.

</DOC>
<DOC>
<DOCNO> 13363 </DOCNO>
Shell Effects in Bubble Nuclei, Atomic Clusters, and Inhomogeneous


  We analyze the character of the shell effects/Casimir energy in inhomogeneous
fermion systems. We estimate magnitude of the shell effects and discuss their
dependence on a number of physical parameters (geometry, fermion density,
temperature).

</DOC>
<DOC>
<DOCNO> 121527 </DOCNO>
Dynamical models for dusty disk galaxies


  Disk galaxies contain a large amount of interstellar dust, which affects the
projection of kinematic quantities. We investigate in detail the effects of
dust extinction on the mean projected velocity and the projected velocity
dispersion. We use our results to construct a general strategy to determine the
dynamical structure of disk galaxies, with the aim to constrain their mass
distribution and dynamical history.

</DOC>
<DOC>
<DOCNO> 7664 </DOCNO>
Generalized symmetric nonextensive thermostatistics and q-modified


  We formulate a convenient generalization of the q-expectation value, based on
the analogy of the symmetric quantum groups and q-calculus, and show that the
q->q^{-1} symmetric nonextensive entropy preserves all of the mathematical
structure of thermodynamics just as in the case of non-symmetric Tsallis
statistics. Basic properties and analogies with quantum groups are discussed.

</DOC>
<DOC>
<DOCNO> 68157 </DOCNO>
New exotics in the double beta decay contributions zoo


  We discuss the potential of neutrinoless double beta decay for testing
Lorentz invariance and the weak equivalence principle as well as contributions
from dilaton exchange gravity in the neutrino sector. While neutrino
oscillation bounds constrain the region of large mixing of the weak and
gravitational eigenstates, we obtain new constraints on violations of Lorentz
invariance and the equivalence principle from neutrinoless double beta decay,
applying even in the case of no mixing. Double beta decay thus probes a totally
unconstrained region in the parameter space.

</DOC>
<DOC>
<DOCNO> 8315 </DOCNO>
Thermoelastic Noise and Homogeneous Thermal Noise in Finite Sized


  An analysis is given of thermoelastic noise (thermal noise due to
thermoelastic dissipation) in finite sized test masses of laser interferometer
gravitational-wave detectors. Finite-size effects increase the thermoelastic
noise by a modest amount; for example, for the sapphire test masses tentatively
planned for LIGO-II and plausible beam-spot radii, the increase is less than or
of order 10 per cent. As a side issue, errors are pointed out in the currently
used formulas for conventional, homogeneous thermal noise (noise associated
with dissipation which is homogeneous and described by an imaginary part of the
Young's modulus) in finite sized test masses. Correction of these errors
increases the homogeneous thermal noise by less than or of order 5 per cent for
LIGO-II-type configurations.

</DOC>
<DOC>
<DOCNO> 170304 </DOCNO>
Transfer of quantum states using finite resources


  We discuss the problem of transfering a qubit from Alice to Bob using a noisy
quantum channel and only finite resources. As the basic protocol for the
transfer we apply quantum teleportation. It turns out that for a certain
quality of the channel direct teleportation combined with qubit purification is
superior to entanglement purification of the channel. If, however, the quality
of the channel is rather low one should simply apply an estimation-preparation
scheme.

</DOC>
<DOC>
<DOCNO> 11495 </DOCNO>
Glassy behaviour in a simple topological model


  In this article we study a simple, purely topological, cellular model which
is allowed to evolve through a Glauber-Kawasaki process. We find a
non-thermodynamic transition to a glassy phase in which the energy (defined as
the square of the local cell topological charge) fails to reach the equilibrium
value below a characteristic temperature which is dependent on the cooling
rate. We investigate a correlation function which exhibits aging behaviour, and
follows a master curve in the stationary regime when time is rescaled by a
factor of the relaxation time t_r. This master curve can be fitted by a von
Schweidler law in the late beta-relaxation regime. The relaxation times can be
well-fitted at all temperatures by an offset Arrhenius law. A power law can be
fitted to an intermediate temperature regime; the exponent of the power law and
the von Schweidler law roughly agree with the relationship predicted by
Mode-coupling Theory. By defining a suitable response function, we find that
the fluctuation-dissipation ratio is held until sometime later than the
appearance of the plateaux; non-monotonicity of the response is observed after
this ratio is broken, a feature which has been observed in other models with
dynamics involving activated processes.

</DOC>
<DOC>
<DOCNO> 100818 </DOCNO>
Random walks on wreath products of groups


  We bound the rate of convergence to uniformity for certain random walks on
the complete monomial groups G \wr S_n for any group G. These results provide
rates of convergence for random walks on a number of groups of interest: the
hyperoctahedral group Z_2 \wr S_n, the generalized symmetric group Z_m \wr S_n,
and S_m \wr S_n. These results provide benchmarks to which many other random
walks, modeling a wide range of phenomena, may be compared using the comparison
technique, thereby yielding bounds on the rates of convergence to uniformity
for previously intractable random walks.

</DOC>
<DOC>
<DOCNO> 102308 </DOCNO>
Transformations of compact locally conformally K\"ahler manifolds


  We characterize compact locally conformally K\"ahler (l.c.K.) manifolds under
the assumption of a purely conformal, holomorphic circle action. As an
application, we determine the structure of the compact l.c.K. manifolds with
parallel Lee form. We introduce the Lee-Cauchy-Riemann (LCR) transformations as
a class of diffeomorphisms preserving the specific $G$-structure of l.c.K.
manifolds. Then we characterize the Hopf manifolds, up to holomorphic isometry,
as compact l.c.K. manifolds admitting a certain closed LCR action of
$\mathbb{C}^*$.

</DOC>
<DOC>
<DOCNO> 151944 </DOCNO>
Self-adjointness of the two-dimensional massless Dirac Hamiltonian and


  A massless spinor field is quantized in the background of a singular static
magnetic vortex in 2+1-dimensional space-time. The method of self-adjoint
extensions is employed to define the most general set of physically acceptable
boundary conditions at the location of the vortex. Under these conditions, the
vacuum energy density and effective potential in the vortex background are
determined.

</DOC>
<DOC>
<DOCNO> 178893 </DOCNO>
Solution of the Faddeev-Yakubovsky equations using realistic NN and 3N


  We solve the Faddeev-Yakubovsky equations for 3N and 4N bound states based on
the most modern realistic nucleon-nucleon interactions. We include different
realistic 3N forces. It is shown that all 3N force models can remove the
underbinding of the triton and alpha-particle which one obtains with existing
NN interactions. The agreement of theoretical predictions and the experimental
binding energy is quite good and there is little room left for the action of
four-nucleon forces in the alpha-particle. The effect of 3N forces on the wave
function is investigated.

</DOC>
<DOC>
<DOCNO> 120484 </DOCNO>
Bizarre Hard X-ray Outbursts of Cygnus X-1


  A very high activity of Cygnus X-1 on 1999 April 19-21 was recorded by BATSE
Large Area Detectors onboard the Compton Gamma-Ray Observatory. The peak
luminosity was one order of magnitude higher than the normal luminosity of Cyg
X-1. This fact can be critical for models of the hard state of Cyg X-1. The
longest outburst lasted ~1000 s and demonstrated very unusual temporal and
spectral behavior which indicates the presence of two emission components. One
component is relatively soft (with a cutoff below 100 keV) and highly variable,
and the other one is hard (extending above 100 keV), with much slower
variability.

</DOC>
<DOC>
<DOCNO> 13480 </DOCNO>
Structural Phase Transition Accompanied by Metal - Insulator Transition


  A structural phase transition has been found using electron diffraction
technique in PrRu4P12 accompanied by a metal - insulator (M - I) transition
(TMI = 60K). Weak superlattice spots appeared at (H, K, L) (H + K + L = 2n + 1;
n is an integer) position at a temperature of T = 12 K and 40 K. Above T = 70
K, the spots completely vanished. The space group of the low temperature phase
is probably Pm3. This is the first observation of a symmetry other than Im3 in
skutterudite compounds.

</DOC>
<DOC>
<DOCNO> 120029 </DOCNO>
Theoretical Calculations of Atomic Data for Spectroscopy


  Several different approximations and techniques have been developed for the
calculation of atomic structure, ionization, and excitation of atoms and ions.
These techniques have been used to compute large amounts of spectroscopic data
of various levels of accuracy. This paper presents a review of these
theoretical methods to help non-experts in atomic physics to better understand
the qualities and limitations of various data sources and assess how reliable
are spectral models based on those data.

</DOC>
<DOC>
<DOCNO> 10770 </DOCNO>
Spectral Properties of Coupled Bose-Einstein Condensates


  We investigate the energy spectrum structure of a system of two (identical)
interacting bosonic wells occupied by N bosons within the Schwinger realization
of the angular momentum. This picture enables us to recognize the symmetry
properties of the system Hamiltonian H and to use them for characterizing the
energy eigenstates. Also, it allows for the derivation of the single-boson
picture which is shown to be the background picture naturally involved by the
secular equation for H. After deriving the corresponding eigenvalue equation,
we recast it in a recursive N-dependent form which suggests a way to generate
the level doublets (characterizing the H spectrum) via suitable inner
parameters. Finally, we show how the presence of doublets in the spectrum
allows to recover, in the classical limit, the symmetry breaking effect that
characterizes the system classically.

</DOC>
<DOC>
<DOCNO> 118948 </DOCNO>
Direct Observation of the Fourth Star in the Zeta Cancri System


  Direct imaging of the zeta Cnc system has resolved the fourth star in the
system, which is in orbit around zeta Cnc C. The presence of the fourth star
has been inferred for many years from irregularities in the motion of star C,
and recently from C's spectroscopic orbit. However, its mass is close to that
of C, making its non-detection puzzling. Observing at wavelengths of 1.2, 1.7,
and 2.2 microns with the adaptive-optics system of the CFHT, we have obtained
images which very clearly reveal star D and show it to have the color of an M2
star. Its brightness is consonant with its being two M stars, which are not
resolved in our observations but are likely to be in a short-period orbit,
thereby accounting for the large mass and the difficulty of detection at
optical wavelengths, where the magnitude difference is much larger. The
positions and colors of all four stars in the system are reported and are
consistent with the most recent astrometric observations.

</DOC>
<DOC>
<DOCNO> 174474 </DOCNO>
S-wave eta'-proton FSI; phenomenological analysis of near-threshold


  We describe a novel technique for comparing total cross sections for the
reactions pp --> pp pi(0), pp --> pp eta, and pp --> pp eta' close to
threshold. The initial and final state proton-proton interactions are factored
out of the total cross section, and the dependence of this reduced cross
section on the volume of phase space is discussed. Different models of the
proton-proton interaction are compared. We argue that the scattering length of
the S-wave eta'-proton interaction is of the order of 0.1 fm.

</DOC>
<DOC>
<DOCNO> 71156 </DOCNO>
Heavy quark production in $\gamma\gamma$ collisions: a theoretical


  Heavy quark production in $\gamma\gamma$ collisions is reanalyzed. It is
argued that evaluating the cross section $\sigma(\gamma\gamma\to
Q\overline{Q})$ in a well-defined renormalization scheme requires the inclusion
of direct photon contributions up to the order $\alpha^2\alpha_s^2$. The order
$\alpha^2\alpha_s^2$ direct photon contributions are furthermore needed for
factorization scale invariance of the sum of direct and resolved photon
contributions. The importance of quantitative analysis of renormalization and
factorization scale dependence of the approximation currently used for the
evaluation of $\sigma(\gamma\gamma\to Q\overline{Q})$ is emphasized as the only
way of estimating the theoretical uncertainty related to the ambiguity in
choosing these scales.

</DOC>
<DOC>
<DOCNO> 170611 </DOCNO>
Formal context for cryptographic models


  To clarify what is involved in linking models to instruments, we adapt
quantum mechanics to define models that display explicitly the points at which
they can be linked to statistics of results of the use of instruments.
Extending an earlier proof that linking models to instruments takes guesswork,
we show: Any model of cryptographic instruments can be *enveloped*,
nonuniquely, by another model that expresses conditions of instruments that
must be met if the first model is to fit a set of measured outcomes. As a
result, model A of key distribution can be enveloped in various ways to reveal
alternative models that Eve can try to implement, in conflict with model A and
its promise of security. A different enveloping model can help Alice and Bob by
expressing necessities of synchronization that they manipulate to improve their
detection of eavesdropping. Finally we show that models based on pre-quantum
physics are also open to envelopment.

</DOC>
<DOC>
<DOCNO> 83098 </DOCNO>
A database and lexicon of scripts for ThoughtTreasure


  Since scripts were proposed in the 1970's as an inferencing mechanism for AI
and natural language processing programs, there have been few attempts to build
a database of scripts. This paper describes a database and lexicon of scripts
that has been added to the ThoughtTreasure commonsense platform. The database
provides the following information about scripts: sequence of events, roles,
props, entry conditions, results, goals, emotions, places, duration, frequency,
and cost. English and French words and phrases are linked to script concepts.

</DOC>
<DOC>
<DOCNO> 151356 </DOCNO>
New Solutions for Evolution of the Scale Factor with a Variable


  The cosmological term is assumed to be a function of time such as $\Lambda
=Ba^{-2}$ where a(t) means the scale factor of standard cosmology. Analytical
solutions for radiation dominated epoch and open universe are found. For closed
universe, k=+1, and for flat universe, k=0, we show a numerical solution. In
general the scenario of Big Bang is preserved in our case for the
Friedmann-Robertson-Walker cosmology.

</DOC>
<DOC>
<DOCNO> 122882 </DOCNO>
On the viewing angle to broad-lined radio galaxies


  We address the nature of broad-lined radio galaxies, in particular their
radio axis orientation, using new, matched resolution, dual frequency radio
observations of a sample of twelve nearby broad-lined extragalactic 3C objects.
Radio spectral index and depolarisation asymmetries indicate that these objects
have a preferred orientation with respect to the observer. In addition, the
spectral asymmetries are suggestive of lower Doppler factors in the broad-lined
radio galaxies when compared to 3C quasars. This is in agreement with their
optical properties, and leads to the conclusion that some objects are lower
powered versions-at similar lines of sight-of the more distant quasars, whereas
others are at larger angles to the line of sight.

</DOC>
<DOC>
<DOCNO> 169590 </DOCNO>
Sensitivity to measurement perturbation of single atom dynamics in


  We consider continuous observation of the nonlinear dynamics of single atom
trapped in an optical cavity by a standing wave with intensity modulation. The
motion of the atom changes the phase of the field which is then monitored by
homodyne detection of the output field. We show that the conditional Hilbert
space dynamics of this system, subject to measurement induced perturbations,
depends strongly on whether the corresponding classical dynamics is regular or
chaotic. If the classical dynamics is chaotic the distribution of conditional
Hilbert space vectors corresponding to different observation records tends to
be orthogonal. This is a characteristic feature of hypersensitivity to
perturbation for quantum chaotic systems.

</DOC>
<DOC>
<DOCNO> 11070 </DOCNO>
The Fermion-Boson Transformation in Fractional Quantum Hall Systems


  A Fermion to Boson transformation is accomplished by attaching to each
Fermion a single flux quantum oriented opposite to the applied magnetic field.
When the mean field approximation is made in the Haldane spherical geometry,
the Fermion angular momentum $l_F$ is replaced by $l_B= l_F-{1\over2}(N-1)$.
The set of allowed total angular momentum multiplets is identical in the two
different pictures. The Fermion and Boson energy spectra in the presence of
many body interactions are identical if and only if the pseudopotential is
``harmonic'' in form. However, similar low energy bands of states with Laughlin
correlations occur in the two spectra if the interaction has short range. The
transformation is used to clarify the relation between Boson and Fermion
descriptions of the hierarchy of condensed fractional quantum Hall states.

</DOC>
<DOC>
<DOCNO> 123170 </DOCNO>
Size determination of the Centaur Chariklo from millimeter-wavelength


  Using the Max-Planck Millimeter Bolometer Array (MAMBO) at the IRAM 30m
telescope we detected emission at 250 GHz from the Centaur Chariklo (1997
CU26). The observed continuum flux density implies a photometric diameter of
273 km. The resulting geometric albedo is 0.055, somewhat higher than expected
from a comparison with most of the other few Centaurs and cometary nuclei for
which such data are available.

</DOC>
<DOC>
<DOCNO> 85209 </DOCNO>
"Self-dual" solutions of topologically massive gravity coupled with the


  We give a general class of exact solutions to the (1+2)-dimensional
topologically massive gravity model coupled with Maxwell-Chern-Simons theory
where a "self-duality" condition is imposed on the Maxwell field.

</DOC>
<DOC>
<DOCNO> 121652 </DOCNO>
Dark matter distribution in the universe and ultra-high energy cosmic


  Two of the greatest mysteries of modern physics are the origin of the dark
matter in the universe and the nature of the highest energy particles in the
cosmic ray spectrum. We discuss here possible direct and indirect connections
between these two problems, with particular attention to two cases: in the
first we study the local clustering of possible sources of ultra-high energy
cosmic rays (UHECRs) driven by the local dark matter overdensity. In the second
case we study the possibility that UHECRs are directly generated by the decay
of weakly unstable super heavy dark matter.

</DOC>
<DOC>
<DOCNO> 80959 </DOCNO>
Non-perturbative Renormalisation with Domain Wall Fermions


  We present results from a study of the renormalisation of both quark bilinear
and four-quark operators for the domain wall fermion action, using the
non-perturbative renormalisation technique of the Rome-Southampton group. These
results are from a quenched simulation, on a 16^3 x 32 lattice, with beta=6.0
and L_s=16.

</DOC>
<DOC>
<DOCNO> 152206 </DOCNO>
Consistency Relations for an Implicit n-dimensional Regularization


  We extend an implicit regularization scheme to be applicable in the
$n$-dimensional space-time. Within this scheme divergences involving parity
violating objects can be consistently treated without recoursing to dimensional
continuation. Special attention is paid to differences between integrals of the
same degree of divergence, typical of one loop calculations, which are in
principle undetermined. We show how to use symmetries in order to fix these
quantities consistently. We illustrate with examples in which regularization
plays a delicate role in order to both corroborate and elucidate the results in
the literature for the case of CPT violation in extended $QED_4$, topological
mass generation in 3-dimensional gauge theories and the Schwinger Model and its
chiral version.

</DOC>
<DOC>
<DOCNO> 178755 </DOCNO>
Compact and Loosely Bound Structures in Light Nuclei


  A role of different components in the wave function of the weakly bound light
nuclei states was studied within the framework of the cluster model, taking
into account of orbitals "polarization". It was shown that a limited number of
structures associated with the different modes of nucleon motion can be of
great importance for such systems. Examples of simple and quite flexible trial
wave functions are given for the nuclei $^8$Be, $^6$He. Expressions for the
microscopic wave functions of these nuclei were found and used for the
calculation of basic nuclear characteristics, using well known central-exchange
nucleon-nucleon potentials.

</DOC>
<DOC>
<DOCNO> 117087 </DOCNO>
A Program for the Geometric Classification of Particles and Relativistic


  Geometric relativistc interactions in a new geometric unified theory are
classified using the dynamic holonomy groups of the connection. Physical
meaning may be given to these interactions if the frame excitations represent
particles. These excitations have algebraic and topological quantum numbers.
The proton, electron and neutrino may be associated to the frame excitations of
the three dynamical holonomy subgroups. In particular, the proton excitation
has a dual mathematical structure of a triplet of subexcitations. Hadronic,
leptonic and gravitational interactions correspond to the same subgroups. The
background geometry determines non trivial fiber bundles where excitations
live, introducing topological quantum numbers that classify families of
excitations. From these three particles, the only stable ones, it may be
possible, as suggested by Barut, to build the rest of the particles. The
combinations of the three fundamental excitations display SU(3)xSU(2)xU(1)
symmetries.

</DOC>
<DOC>
<DOCNO> 11417 </DOCNO>
A variational perturbation scheme for many-particle systems in the


  A variational Perturbation theory based on the functional integral approach
is formulated for many-particle systems. Using the variational action obtained
through Jensen-Peierls' inequality, a perturbative expansion scheme for the
thermodynamic potential is established. A modified Wick's theorem is obtained
for the variational perturbation expansions. This theorem allows one to carry
out systematic calculations of higher order terms without worrying about the
double counting problem. A model numerical calculation was carried out on a
nucleon gas system interacting through the Yukawa-type potential to test the
efficiency of the present method.

</DOC>
<DOC>
<DOCNO> 117032 </DOCNO>
Optimal Control of Molecular Motion Expressed Through Quantum Fluid


  A quantum fluid dynamic control formulation is presented for optimally
manipulating atomic and molecular systems. In quantum fluid dynamic the control
quantum system is expressed in terms of the probability density and the quantum
current. This choice of variables is motivated by the generally expected slowly
varying spatial-temporal dependence of the fluid dynamical variables. The
quantum fluid dynamic approach is illustrated for manipulation of the ground
electronic state dynamics of HCl induced by an external electric field.

</DOC>
<DOC>
<DOCNO> 99630 </DOCNO>
Determinantal random point fields


  The paper contains an exposition of recent as well as old enough results on
determinantal random point fields. We start with some general theorems
including the proofs of the necessary and sufficient condition for the
existence of the determinantal random point field with Hermitian kernel and a
criterion for the weak convergence of its distribution. In the second section
we proceed with the examples of the determinantal random point fields from
Quantum Mechanics, Statistical Mechanics, Random Matrix Theory, Probability
Theory, Representation Theory and Ergodic Theory. In connection with the Theory
of Renewal Processes we characterize all determinantal random point fields in
R^1 and Z^1 with independent identically distributed spacings. In the third
section we study the translation invariant determinantal random point fields
and prove the mixing property of any multiplicity and the absolute continuity
of the spectra. In the fourth (and the last) section we discuss the proofs of
the Central Limit Theorem for the number of particles in the growing box and
the Functional Central Limit Theorem for the empirical distribution function of
spacings.

</DOC>
<DOC>
<DOCNO> 174571 </DOCNO>
The focal plane proton-polarimeter for the 3-spectrometer setup at MAMI


  For experiments of the type A(\vec e,e'\vec p) the 3-spectrometer setup of
the A1 collaboration at MAMI has been supplemented by a focal plane
proton-polarimeter. To this end, a carbon analyzer of variable thickness and
two double-planes of horizontal drift chambers have been added to the standard
detector system of Spectrometer A. Due to the spin precession in the
spectrometer magnets, all three polarization components at the target can be
measured simultaneously. The performance of the polarimeter has been studied
using elastic p(e,e'p) scattering.

</DOC>
<DOC>
<DOCNO> 11685 </DOCNO>
New Mechanism for Electronic Energy Relaxation in Nanocrystals


  The low-frequency vibrational spectrum of an isolated nanometer-scale solid
differs dramatically from that of a bulk crystal, causing the decay of a
localized electronic state by phonon emission to be inhibited. We show,
however, that an electron can also interact with the rigid translational motion
of a nanocrystal. The form of the coupling is dictated by the equivalence
principle and is independent of the ordinary electron-phonon interaction. We
calculate the rate of nonradiative energy relaxation provided by this mechanism
and establish its experimental observability.

</DOC>
<DOC>
<DOCNO> 100813 </DOCNO>
Random polynomials having few or no real zeros


  Consider a polynomial of large degree n whose coefficients are independent,
identically distributed, nondegenerate random variables having zero mean and
finite moments of all orders. We show that such a polynomial has exactly k real
zeros with probability n^{-b+o(1)}$ as n --> infinity through integers of the
same parity as the fixed integer k >= 0. In particular, the probability that a
random polynomial of large even degree n has no real zeros is n^{-b+o(1)}. The
finite, positive constant b is characterized via the centered, stationary
Gaussian process of correlation function sech(t/2). The value of b depends
neither on k nor upon the specific law of the coefficients. Under an extra
smoothness assumption about the law of the coefficients, with probability
n^{-b+o(1)} one may specify also the approximate locations of the k zeros on
the real line. The constant b is replaced by b/2 in case the i.i.d.
coefficients have a nonzero mean.

</DOC>
<DOC>
<DOCNO> 80846 </DOCNO>
Numerical Analysis of the Double Scaling Limit in the bosonic part of


  The bosonic IIB matrix model, which contains the bosonic part of the IIB
matrix model conjectured to be a non-perturbative definition of the type IIB
superstring theory, is studied using a numerical method. The large N scaling
behavior of the model is shown performing a Monte Carlo simulation. The
expectation value of the Wilson loop operator is measured and the string
tension is estimated. From the numerical results, the prescription of the
double scaling limit is obtained.

</DOC>
<DOC>
<DOCNO> 13718 </DOCNO>
The Magnetized Electron Gas in terms of Hurwitz Zeta Functions


  We obtain explicit expressions for thermodynamic quantities of a relativistic
degenerate free electron gas in a magnetic field in terms of Hurwitz Zeta
functions. The formulation allows for systematic expansion in all regimes.
Three energy scales appear naturally in the degenerate relativistic gas: the
Fermi energy Ef, the temperature T and an energy related to the magnetic field
or Landau level spacing, eB/Ef. We study the cold and warm scenarios, T <<
eB/Ef and eB/Ef << T, respectively. We reproduce the oscillations of the
magnetization as a function of the field in the cold regime and the dilution of
them in the warm regime.

</DOC>
<DOC>
<DOCNO> 100378 </DOCNO>
Representations of quantum tori and double-affine Hecke algebras


  We study a BGG-type category of infinite dimensional representations of H[W],
a semi-direct product of the quantum torus with parameter `q' built on the root
lattice of a semisimple group G, and the Weyl group of G. Irreducible objects
of our category turn out to be parameterized by semistable G-bundles on the
elliptic curve C^*/q^Z. In the second part of the paper we construct a family
of algebras depending on a parameter `v' that specializes to H[W] at v=0, and
specializes to the double-affine Hecke algebra introduced by Cherednik, at v=1.
We propose a Deligne-Langlands-Lusztig type conjecture relating irreducible
modules over the double-affine Hecke algebra to Higgs G-bundles on the elliptic
curve. The conjecture may be seen as a natural `v-deformation' of the
classification of simple H[W]-modules obtained in the first part of the paper.
Also, an `operator realization' of the double-affine Hecke algebra, as well as
of its Spherical subalgebra, in terms of certain `zero-residue' conditions is
given.

</DOC>
<DOC>
<DOCNO> 84422 </DOCNO>
A Spacetime Foam approach to the cosmological constant and entropy


  A simple model of spacetime foam, made by $N$ wormholes in a semiclassical
approximation, is taken under examination. The Casimir-like energy of the
quantum fluctuation of such a model and its probability of being realized are
computed. Implications on the Bekenstein-Hawking entropy and the cosmological
constant are considered.

</DOC>
<DOC>
<DOCNO> 70447 </DOCNO>
A superformula for neutrinoless double beta decay II: The short range


  A general Lorentz-invariant parameterization for the short-range part of the
0vBB decay rate is derived. Combined with the long range part already published
this general parameterization in terms of effective B-L violating couplings
allows one to extract the 0vBB limits on arbitrary lepton number violating
theories.

</DOC>
<DOC>
<DOCNO> 101585 </DOCNO>
Lusternik-Schnirelmann Theory for a Morse Decomposition


  Let $\phi^t$ be a continuous flow on a metric space $X$ and $I$ be an
isolated invariant set with an index pair $(N,L)$ and a Morse decomposition
$\{M_i\}^n_{i=1}$. For every category $\nu$ on $N/L$, we prove that
$\nu(N/L)\leq \nu([L])+\sum_{i=1}^n \nu(M_i)$. As a result if $\phi^t|_I$ is
gradient-like and $X$ is semi-locally contractible, then $\phi^t$ has at least
$\nu_H(h(I))-1$ rest points in $I$ where $h(I)$ is the Conley index of $I$ and
$\nu_H$ is the Homotopy Lusternik-Schnirelmann category.

</DOC>
<DOC>
<DOCNO> 40101 </DOCNO>
Investigation of an angular distribution of protons in peripheral and


  The experimental results on the relation between the number of events, the
angular distributions of protons and full number of protons are presented for
${}^{12}CC$-interactions at the momentum of 4.2 A GeV/c. The influence of
nuclear fragmentation process on the results is also considered. The obtai- ned
results confirm the assumption that there exist the critical phenomena among
the central collisions and it is necessary to use a percolation approa- ch for
the full description of the central collisions.

</DOC>
<DOC>
<DOCNO> 70421 </DOCNO>
Neutrino mass, bulk majoron and neutrinoless double beta decay


  A new economical model for neutrino masses is proposed in the context of
brane bulk scenarios for particle physics, where global B-L symmetry of the
standard model is broken spontaneously by a gauge singlet Higgs field in the
bulk. This leads to a bulk majoron whose KK excitations may make it visible if
neutrinoless double beta decay if the string scale is close to a TeV. It also
leads to neutron-anti-neutron oscillation process with transition times which
can be in the range accessible to proposed experiments.

</DOC>
<DOC>
<DOCNO> 68600 </DOCNO>
Semi-inclusive structure functions in the spectator model


  We establish the relationship between distribution and fragmentation
functions and the structure functions appearing in the cross section of
polarized 1-particle inclusive deep-inelastic scattering. We present spectator
model evaluations of these structure functions focusing on the case of an
outgoing spin-1/2 baryon. Distribution functions obtained in the spectator
model are known to fairly agree at low energy scales with global
parameterizations extracted, for instance, from totally inclusive DIS data.
Therefore, we expect it to give good hints on the functional dependence of the
structure functions on the scaling variables x(Bjorken), z and on the
transverse momentum of the observed outgoing hadron, P_{h\perp}. Presently,
this dependence is not very well known, but experiments are planned in the near
future.

</DOC>
<DOC>
<DOCNO> 100810 </DOCNO>
First Fundamental Theorem of Invariant Theory for covariants of


  Let $U(G)$ be a maximal unipotent subgroup of one of classical groups
$G=GL(V),O(V),Sp(V)$. Let $W$ be a direct sum of copies of $V$ and its dual
$V*$. For the natural action $U(G):W$, we describe a minimal system of
homogeneous generators for the algebra of $U(G)$-invariant regular functions on
$W$. For $G=GL(V)$, we also describe the syzygies among these generators in
some particular cases.

</DOC>
<DOC>
<DOCNO> 70070 </DOCNO>
Large-x Parton Distributions


  Reliable knowledge of parton distributions at large x is crucial for many
searches for new physics signals in the next generation of collider
experiments. Although these are generally well determined in the small and
medium x range, it has been shown that their uncertainty grows rapidly for
x>0.1. We examine the status of the gluon and quark distributions in light of
new questions that have been raised in the past two years about "large-x"
parton distributions, as well as recent measurements which have improved the
parton uncertainties. Finally, we provide a status report of the data used in
the global analysis, and note some of the open issues where future experiments,
including those planned for Jefferson Labs, might contribute.

</DOC>
<DOC>
<DOCNO> 39678 </DOCNO>
Lepton Energy Asymmetry and Precision SUSY study at Hadron Colliders


  We study the distribution of lepton pairs from the second lightest neutralino
decay \tilde{\chi}^0_2-->\tilde{l}l followed by \tilde{l}\to \tilde{\chi}^0_1
l. The distribution of the ratio of lepton transverse momenta A_T shows peak
structure if m_{ll}< m^{max}_{ll}/2 is required. The peak position A_T^{peak}
is described by a simple function of the ino and slepton masses in the
m_{ll}\sim 0 limit. When a moderate m_{ll} cut is applied, A_T^{peak} depends
on the \tilde{\chi}^0_2 velocity distribution, but the dependence would be
corrected by studying the lepton P_T distribution. A_T^{peak} and the edge of
m_{ll} distributions are used to determine the mass parameters involved in the
decay for parameters of interest to LHC experiments. For some cases the ino and
slepton masses may be determined within 10% by the lepton distribution only
independent of model assumptions. Correct combinations of A_{T}^{peak} and
m_{ll}^{edge} would be identified even if different \tilde{\chi}^0_2 decay
chains are co-existing. The analysis could be extended to the Tevatron energy
scale or other cascade decays.

</DOC>
<DOC>
<DOCNO> 99785 </DOCNO>
Bifurcating Continued Fractions


  The notion of 'bifurcating continued fractions' is introduced. Two coupled
sequences of non-negative integers are obtained from an ordered pair of
positive real numbers in a manner that generalizes the notion of continued
fractions. These sequences enable simple representations of roots of cubic
equations. In particular, remarkably simple and elegant 'bifurcating continued
fraction' representations of Tribonacci and Moore numbers, the cubic variations
of the 'golden mean', are obtained. This is further generalized to associate m
non-negative integer sequences with a set of m given real numbers so as to
provide simple 'bifurcating continued fraction' representation of roots of
polynomial equations of degree m+1.

</DOC>
<DOC>
<DOCNO> 12890 </DOCNO>
From favorable atomic configurations to supershell structures: a new


  Title: From favorable atomic configurations to supershell structures: a new
interpretation of conductance histograms Authors: A. Hasmy (IVIC), E. Medina
(IVIC), P.A. Serena (CSIC,IVIC) Comments: 7 pages, 3 figures,
cond-mat.anwar.10825 Subj-class: Soft Condensed Matter

</DOC>
<DOC>
<DOCNO> 178525 </DOCNO>
Neutron matter with a model interaction


  An infinite system of neutrons interacting by a model pair potential is
considered. We investigate a case when this potential is sufficiently strong
attractive, so that its scattering length tends to infinity. It appeared, that
if the structure of the potential is simple enough, including no finite
parameters, reliable evidences can be presented that such a system is
completely unstable at any finite density. The incompressibility as a function
of the density is negative, reaching zero value when the density tends to zero.
If the potential contains a sufficiently strong repulsive core then the system
possesses an equilibrium density. The main features of a theory describing such
systems are considered.

</DOC>
<DOC>
<DOCNO> 116332 </DOCNO>
Femtosecond soliton amplification in nonlinear dispersive traps and


  The nonlinear pulse propagation in an optical fibers with varying parameters
is investigated. The capture of moving in the frequency domain femtosecond
colored soliton by a dispersive trap formed in an amplifying fiber makes it
possible to accumulate an additional energy and to reduce significantly the
soliton pulse duration. Nonlinear dynamics of the chirped soliton pulses in the
dispersion managed systems is also investigated. The methodology developed does
provide a systematic way to generate infinite ``ocean'' of the chirped soliton
solutions of the nonlinear Schr\"odinger equation (NSE) with varying
coefficients.

</DOC>
<DOC>
<DOCNO> 80955 </DOCNO>
Towards the lattice study of M-theory


  We propose the Wilson discretization of the supersymmetric Yang-Mills Quantum
Mechanics as a lattice version of the matrix model of M-theory. An SU(2) model
is studied numerically in the quenched approximation for D=4. A clear signal
for the existence of two different phases is found and the continuum
pseudocritical temperature is determined. We have also extracted the continuum
limit of the total size of the system in both phases and for different
temperatures.

</DOC>
<DOC>
<DOCNO> 80985 </DOCNO>
Comparing Clusters and Supercomputers for Lattice QCD


  Since the development of the Beowulf project to build a parallel computer
from commodity PC components, there have been many such clusters built. The
MILC QCD code has been run on a variety of clusters and supercomputers. Key
design features are identified, and the cost effectiveness of clusters and
supercomputers are compared.

</DOC>
<DOC>
<DOCNO> 71228 </DOCNO>
Q-Ball Collisions in the MSSM


  Collisions of non-topological solitons, Q-balls, are studied in the Minimal
Supersymmetric Standard Model in two different cases: where supersymmetry has
been broken by a gravitationally coupled hidden sector and by a gauge mediated
mechanism at a lower energy scale. Q-ball collisions are studied numerically on
a two dimensional lattice for a range of Q-ball charges. Total cross-sections
as well as cross-sections for fusion and charge exchange are calculated.

</DOC>
<DOC>
<DOCNO> 9149 </DOCNO>
Ground State Energy Calculations of the \nu=1/2 and the \nu=5/2 FQHE


  We reconsider energy calculations of the spin polarized $\nu=1/2$
Chern-Simons theory. We show that one has to be careful in the definition of
the Chern-Simons path integral in order to avoid an IR divergent magnetic
ground state energy in RPA as in \cite{di1}. We correct the path integral and
get a well behaved magnetic energy by considering the energy of the maximal
divergent graphs as well as the Hartree-Fock graphs. Furthermore, we consider
the $\nu=1/2$ and the $\nu=5/2$ system with spin degrees of freedom. In doing
this we formulate a Chern-Simons theory of the $\nu=5/2$ system by transforming
the interaction operator to the next lower Landau level. We calculate the
Coulomb energy of the spin polarized as well as the spin unpolarized $\nu=1/2$
and the $\nu=5/2$ system as a function of the interaction strength in RPA.
These energies are in good agreement with numerical simulations of interacting
electrons in the first as well as in the second Landau level. Furthermore, we
calculate the compressibility, the effective mass and the excitations of the
spin polarized $\nu=2+1/\tilde{\phi}$ systems where $\tilde{\phi}$ is an even
number.

</DOC>
<DOC>
<DOCNO> 13329 </DOCNO>
SET based experiments for HTSC materials


  The cuprates seem to exhibit statistics, dimensionality and phase transitions
in novel ways. The nature of excitations [i.e. quasiparticle or collective],
spin-charge separation, stripes [static and dynamics], inhomogeneities,
psuedogap, effect of impurity dopings [e.g. Zn, Ni] and any other phenomenon in
these materials must be consistently understood. In this note we suggest Single
Electron Tunneling Transistor [SET] based experiments to understand the role of
charge dynamics in these systems. Assuming that SET operates as an efficient
charge detection system we can expect to understand the underlying physics of
charge transport and charge fluctuations in these materials for a range of
doping.
  Experiments such as these can be classed in a general sense as mesoscopic and
nano characterization of cuprates and related materials.

</DOC>
<DOC>
<DOCNO> 84897 </DOCNO>
The excitation of a charged string passing through a shock wave in a


  We investigate how much a first-quantized charged bosonic test string gets
excited after crossing a shock wave generated by a charged particle with mass
$\tilde{M}$ and charge $\tilde{Q}$. On the basis of Kaluza-Klein theory, we pay
attention to a closed string model where charge is given by a momentum along a
compactified extra-dimension. The shock wave is given by a charged
Aichelburg-Sexl (CAS) spacetime where $\tilde{Q}=0$ corresponds to the ordinary
Aichelburg-Sexl one. We first show that the CAS spacetime is a solution to the
equations of motion for the metric, the gauge field, and the axion field in the
low-energy limit. Secondly, we compute the mass expectation value of the
charged test string after passing through the shock wave in the CAS spacetime.
  In the case of small $\tilde{Q}$, gravitational and Coulomb forces are
canceled out each other and hence the excitation of the string remains very
small. This is independent of the particle mass $\tilde{M}$ or the strength of
the shock wave. In the case of large $\tilde{Q}$, however, every charged string
gets highly excited by quantum fluctuation in the extra-dimension caused by
both the gauge and the axion fields. This is quite different from classical
"molecule", which consists of two electrically charged particles connected by a
classical spring.

</DOC>
<DOC>
<DOCNO> 151460 </DOCNO>
T-dual R-R zero-norm states, D-branes and S-duality of type II string


  We calculate the R-R zero-norm states of type II string spectrum. To fit
these states into the right symmetry charge parameters of the gauge
transformations of the R-R tensor forms, one is forced to T-dualize some type I
open string space-time coordinates and thus to introduce D-branes into the
theory. We also demonstrate that the constant T-dual R-R 0-form zero-norm
state, together with the NS-NS singlet zero-norm state are responsible for the
SL(2,Z) S-duality symmetry of the type II B string theory.

</DOC>
<DOC>
<DOCNO> 83149 </DOCNO>
TnT - A Statistical Part-of-Speech Tagger


  Trigrams'n'Tags (TnT) is an efficient statistical part-of-speech tagger.
Contrary to claims found elsewhere in the literature, we argue that a tagger
based on Markov models performs at least as well as other current approaches,
including the Maximum Entropy framework. A recent comparison has even shown
that TnT performs significantly better for the tested corpora. We describe the
basic model of TnT, the techniques used for smoothing and for handling unknown
words. Furthermore, we present evaluations on two corpora.

</DOC>
<DOC>
<DOCNO> 71409 </DOCNO>
Screening in Hot SU(2) Gauge Theory and Propagators in 3d Adjoint Higgs


  We investigate the large distance behavior of the electric and magnetic
propagators of hot SU(2) gauge theory in different gauges using lattice
simulations of the full 4d theory and the effective, dimensionally reduced 3d
theory. A comparison of the 3d and 4d data for the propagators suggests that
dimensional reduction works surprisingly well down to temperatures T=2 T_c. A
detailed study of the volume dependence of magnetic propagators is performed.
The electric propagators show exponential decay at large distances in all
gauges considered and a possible gauge dependence of the electric screening
mass turns out to be statistically insignificant.

</DOC>
<DOC>
<DOCNO> 100000 </DOCNO>
Moduli of Riemann Surfaces, Transcendental Aspects


  This is an informal set of lecture notes on moduli spaces of curves based on
a set of lectures given at the ICTP last summer. It begins at an elementary
level and discusses the genus 1 case in detail. The notes then give an informal
treatement of Teichmuller space and higher genus moduli spaces. The point of
view is generally topological and analytical.

</DOC>
<DOC>
<DOCNO> 80891 </DOCNO>
Chiral Symmetry Breaking for Domain Wall Fermions in Quenched Lattice


  The domain wall fermion formulation exhibits full chiral symmetry for finite
lattice spacing except for the effects of mixing between the domain walls.
Close to the continuum limit these symmetry breaking effects should be
described by a single residual mass. We determine this mass from the
conservation law obeyed by the conserved axial current in quenched simulations
with beta=5.7 and 6.0 and domain wall separations varying between 12 and 48 on
8^3x32 and 16^3x32 lattices. Using the resulting values for the residual mass
we perform two complete and independent calculations of the pion decay
constant. Good agreement is found between these two methods and with
experiment.

</DOC>
<DOC>
<DOCNO> 122945 </DOCNO>
Mapping the Dynamics of the Quasar 3C 48


  The archetypical, nearby (z=0.37) quasar 3C 48 is an unusual CSS radio source
with excess far-IR emission, whose one-sided radio jet is aligned with the
extended ionized emission and a putative second nucleus. Because of its high
AGN luminosity and proximity, 3C 48 is a good candidate to search for kinematic
signatures of the radio jet-gas coupling and/or of a recent interaction. The
radio morphology and our ground-based integral field spectroscopy suggest that
the jet is interacting with its immediate environment. Using STIS aboard HST in
several slit positions within the central 1", we map the kinematics and
physical conditions of the extended emission line gas and their relations to
near-nuclear star forming regions found in existing HST images.

</DOC>
<DOC>
<DOCNO> 101503 </DOCNO>
2-adic behavior of numbers of domino tilings


  We study the 2-adic behavior of the number of domino tilings of a 2n-by-2n
square as nvaries. It was previously known that this number was of the form 2^n
f(n)^2, where f(n) is an odd, positive integer. We show that the function f is
uniformly continuous under the 2-adic metric, and thus extends to a function on
all of Z. The extension satisfies the functional equation f(-1-n) = +- f(n),
where +- sign is + if n is congruent to 0 or 3 modulo 4 and - otherwise.

</DOC>
<DOC>
<DOCNO> 10790 </DOCNO>
On two intrinsic length scales in polymer physics: topological


  The interplay of topological constraints, excluded volume interactions,
persistence length and dynamical entanglement length in solutions and melts of
linear chains and ring polymers is investigated by means of kinetic Monte Carlo
simulations of a three dimensional lattice model. In unknotted and
unconcatenated rings, topological constraints manifest themselves in the static
properties above a typical length scale $dt \sim 1/\sqrt{l\phi}$ ($\phi$ being
the volume fraction, $l$ the mean bond length).
  Although one might expect that the same topological length will play a role
in the dynamics of entangled polymers, we show that this is not the case.
Instead, a different intrinsic length de, which scales like excluded volume
blob size $\xi$, governs the scaling of the dynamical properties of both linear
chains and rings.

</DOC>
<DOC>
<DOCNO> 8269 </DOCNO>
Symmetry alteration of ensemble return distribution in crash and rally


  We select the $n$ stocks traded in the New York Stock Exchange and we form a
statistical ensemble of daily stock returns for each of the $k$ trading days of
our database from the stock price time series. We study the ensemble return
distribution for each trading day and we find that the symmetry properties of
the ensemble return distribution drastically change in crash and rally days of
the market. We compare these empirical results with numerical simulations based
on the single-index model and we conclude that this model is unable to explain
the behavior of the market in extreme days.

</DOC>
<DOC>
<DOCNO> 72281 </DOCNO>
Propagation of Muons and Taus at High Energies


  The photonuclear contribution to charged lepton energy loss has been
re-evaluated taking into account HERA results on real and virtual photon
interactions with nucleons. With large $Q^2$ processes incorporated, the
average muon range in rock for muon energies of $10^9$ GeV is reduced by only
5% as compared with the standard treatment. We have calculated the tau energy
loss for energies up to $10^9$ GeV taking into consideration the decay of the
tau. A Monte Carlo evaluation of tau survival probability and range show that
at energies below $10^7-10^8$ GeV, depending on the material, only tau decays
are important. At higher energies the tau energy losses are significant,
reducing the survival probability of the tau. We show that the average range
for tau is shorter than its decay length and reduce to 17 km in water for an
incident tau energy of $10^9$ GeV, as compared with its decay length of 49 km
at that energy. In iron, the average tau range is 4.7 km for the same incident
energy.

</DOC>
<DOC>
<DOCNO> 9650 </DOCNO>
Non-abelian quantum Hall states - exclusion statistics, K-matrices and


  We study excitations in edge theories for non-abelian quantum Hall states,
focussing on the spin polarized states proposed by Read and Rezayi and on the
spin singlet states proposed by two of the authors. By studying the exclusion
statistics properties of edge-electrons and edge-quasiholes, we arrive at a
novel K-matrix structure. Interestingly, the duality between the electron and
quasihole sectors links the pseudoparticles that are characteristic for
non-abelian statistics with composite particles that are associated to the
`pairing physics' of the non-abelian quantum Hall states.

</DOC>
<DOC>
<DOCNO> 120021 </DOCNO>
Non-equilibrium Ionization and FIP Effect Diagnostics


  We examine the accuracy of a common FIP effect diagnostic, the ratio of Ne VI
to Mg VI lines in the solar transition region. Since the two ions have quite
similar contribution functions near their maxima in equilibrium, the ratio of
these two ions is often taken to be the abundance ratio of Ne and Mg. First we
compute non-equilibrium ionization effects on the ratio f(Ne+5)/f(Mg+5) of ion
fractions for a variety of simple flows through the transition region.
Calculating the spectral line ratios for a few examples, we then show that
non-equilibrium effects as well as temperature and density dependence must be
evaluated for each line ratio used in the diagnostics.

</DOC>
<DOC>
<DOCNO> 122962 </DOCNO>
Deep HST Imaging of IC 1613. I. Variable Stars and Distance


  We present WFPC2 VI photometry of a field in the halo of IC 1613, finding 13
RR Lyraes and 11 Cepheids. Our photometry of the red giant branch tip and red
clump is used to derive distances to IC 1613, which are consistent with each
other and with distances based on the variable stars. We compare these values
with similarly-measured distances for the Magellanic Clouds, and are able to
measure metallicity dependencies of the RR Lyrae and Cepheid distances by
requiring consistent relative distance measurements from the four techniques.
For metallicities of [Fe/H] = -1.3 (RR Lyraes) and -1.0 (Cepheids), we find a
relatively steep slope of 0.34 +/- 0.20 magnitudes per dex for the RR Lyraes
and a shallow slope of -0.07 +/- 0.16 mag/dex for the Cepheids, both values
within the range of theoretical and empirical results in the literature. We
find that a dependence of the red clump absolute magnitude on age, in addition
to metallicity, is required to produce self-consistent relative distances
between IC 1613 and the Magellanic Clouds. Adopting such a red clump
calibration and self-consistent calibrations for the other three distance
indicators, we find that the distances to all three objects are in excellent
agreement. Our best distance modulus to IC 1613 is mu_0 = 24.31 +/- 0.06,
corresponding to a distance of 730 +/- 20 kpc. This distance produces an RR
Lyrae absolute magnitude of MV = 0.61 +/- 0.08.

</DOC>
<DOC>
<DOCNO> 116635 </DOCNO>
Comment on "Observation of Superluminal Behaviors in Wave Propagation"


  Mugnai et al. have reported an experiment in which microwave packets appear
to travel in air with a speed substantially greater than c. They calculate the
group velocity of their packets and find that it agrees with their experimental
result. That calculation is incorrect. A correct calculation gives a group
velocity less than c. The reported experimental result cannot be reconciled
with the Maxwell equations.

</DOC>
<DOC>
<DOCNO> 152488 </DOCNO>
Gravity localization on string-like defects in codimension two and the


  We study the localization of gravity on string-like defects in codimension
two. We point out that the gravity-localizing `local cosmic string' spacetime
has an orbifold singularity at the horizon. The supergravity embedding and the
AdS/CFT correspondence suggest ways to resolve the singularity. We find two
resolutions of the singularity that have a semiclassical gravity description
and study their effect on the low-energy physics on the defect. The first
resolution leads, at long distances, to a codimension one Randall-Sundrum
scenario. In the second case, the infrared physics is like that of a
conventional finite-size Kaluza-Klein compactification, with no power-law
corrections to the gravitational potential. Similar resolutions apply also in
higher codimension gravity-localizing backgrounds.

</DOC>
<DOC>
<DOCNO> 100767 </DOCNO>
On the converse to a theorem of Atiyah and Bott


  Let G be a complex reductive group and let C be a smooth curve of genus at
least one. We prove a converse to a theorem of Atiyah-Bott concerning the
stratification of the space of holomorphic G-bundles on C. In case the genus of
C is one, we establish that one has a stratification in the strong sense. The
paper concludes with a characterization of the minimally unstable strata in
case G is simple.

</DOC>
<DOC>
<DOCNO> 85172 </DOCNO>
Quantum Theory within the Framework of General Relativity


  A local conception is proposed to reconcile quantum theory with general
relativity, which allows one to avoid some difficulties --- as e.g. vacuum
catastrophe --- of the global approach.

</DOC>
<DOC>
<DOCNO> 123105 </DOCNO>
The Southern Galactic Plane Survey: The Test Region


  The Southern Galactic Plane Survey (SGPS) is a project to image the HI line
emission and 1.4 GHz continuum in the fourth quadrant of the Milky Way at high
resolution using the Australia Telescope Compact Array (ATCA) and the Parkes
Radio Telescope. In this paper we describe the survey details and goals,
present lambda 21-cm continuum data, and discuss HI absorption and emission
characteristics of the SGPS Test Region (325.5 deg < l < 333.5 deg; -0.5 deg <
b < +3.5 deg). We explore the effects of massive stars on the interstellar
medium (ISM) through a study of HI shells and the HI environments of HII
regions and supernova remnants. We find an HI shell surrounding the HII region
RCW 94 which indicates that the region is embedded in a molecular cloud. We
give lower limits for the kinematic distances to SNRs G327.4+0.4 and G330.2+1.0
of 4.3 kpc and 4.9 kpc, respectively. We find evidence of interaction with the
surrounding HI for both of these remnants. We also present images of a possible
new SNR G328.6-0.0. Additionally, we have discovered two small HI shells with
no counterparts in continuum emission.

</DOC>
<DOC>
<DOCNO> 174551 </DOCNO>
Single-neutron transfer from 11Be gs via the (p,d) reaction with a


  The 11Be(p,d)10Be reaction has been performed in inverse kinematics with a
radioactive 11Be beam of E/A = 35.3 MeV. Angular distributions for the 0+
ground state, the 2+, 3.37 MeV state and the multiplet of states around 6 MeV
in 10Be were measured at angles up to 16 deg CM by detecting the 10Be in a
dispersion-matched spectrometer and the coincident deuterons in a silicon
array. Distorted wave and coupled-channels calculations have been performed to
investigate the amount of 2+ core excitation in 11Be gs. The use of "realistic"
11Be wave functions is emphasised and bound state form factors have been
obtained by solving the particle-vibration coupling equations. This calculation
gives a dominant 2s component in the 11Be gs wave function with a 16% [2+ x 1d]
core excitation admixture. Cross sections calculated with these form factors
are in good agreement with the present data. The Separation Energy prescription
for the bound state wave function also gives satisfactory fits to the data, but
leads to a significantly larger [2 x 1d] component in 11Be gs.

</DOC>
<DOC>
<DOCNO> 152118 </DOCNO>
Supersymmetric higher-derivative actions in ten and eleven dimensions,


  Higher-derivative terms in the string and M-theory effective actions are
strongly constrained by supersymmetry. Using a mixture of techniques, involving
both string amplitude calculations and an analysis of supersymmetry
requirements, we determine the supersymmetric completion of the R^4 action in
eleven dimensions to second order in the fermions, in a form compact enough for
explicit further calculations. Using these results, we obtain the modifications
to the field transformation rules and determine the resulting field-dependent
modifications to the coefficients in the supersymmetry algebra. We then make
the link to the superspace formulation of the theory and discuss the mechanism
by which higher-derivative interactions lead to modifications to the
supertorsion constraints. For the particular interactions under discussion we
find that no such modifications are induced.

</DOC>
<DOC>
<DOCNO> 40056 </DOCNO>
Scrutinizing LSP Dark Matter at the LHC


  We show that LHC experiments might well be able to determine all the
parameters required for a prediction of the present density of thermal LSP
relics from the Big Bang era. If the LSP is an almost pure bino we usually only
need to determine its mass and the mass of the SU(2) singlet sleptons. This
information can be obtained by reconstructing the cascade $\tilde{q}_L \to
\tilde{\chi}_2^0 q \to \tilde{\ell}_R \ell q \to \tilde{\chi}_1^0 \ell^+ \ell^-
q$. The only requirement is that $m_{\tilde{\ell}_R} < m_{\tilde{\chi}_2^0}$,
which is true for most of the cosmologically interesting parameter space. If
the LSP has a significant higgsino component, its predicted thermal relic
density is smaller than for an equal--mass bino. We show that in this case
squark decays also produce significant numbers of $\tilde{\chi}_4^0$ and
$\tilde{\chi}_2^\pm$. Reconstructing the corresponding decay cascades then
allows to determine the higgsino component of the LSP.

</DOC>
<DOC>
<DOCNO> 12330 </DOCNO>
Luminescence Spectra of a Quantum-Dot Cascade Laser


  A quantum cascade laser where the quantum wells in the active regions are
replaced by quantum dots with their atom-like discrete energy levels is an
interesting system to study novel features in optical spectroscopy. We study
structures suitable for diagonal lasing transitions in coupled dots, and
vertical lasing transitions in a single dot, in the active regions of the laser
device. The luminescence spectra as a function of electron number and dot size
show that for diagonal transitions, a significant amount of blue-shift in the
emission spectra can be achieved by increasing electron population in the
quantum dots as well as by decreasing the size of the dots.

</DOC>
<DOC>
<DOCNO> 68953 </DOCNO>
Finite formation time effects in quasi-elastic $(e,e')$ scattering on


  The problem of the final state interaction in quasi-elastic $(e,e')$
scattering at large $Q^2$, is investigated by exploiting the idea that the
ejected nucleon needs a finite amount of time to assume its asymptotic form. It
is shown that when the dependence of the scattering amplitude of the ejected
nucleon on its virtuality is taken into account, the final state interaction is
decreased. The developed approach is simpler to implement than the one based on
the color transparency description of the damping of the final state
interaction, and is essentially equivalent to the latter in the case of the
single rescattering term. The $(e,e')$ process on the deuteron is numerically
investigated and it is shown that, at $x=1$, appreciable finite formation time
effects at $Q^2$ of the order of 10 (GeV/c)$^2$ are expected.

</DOC>
<DOC>
<DOCNO> 85388 </DOCNO>
General Relativistic Electromagnetic Fields of a Slowly Rotating


  We present analytic solutions of Maxwell equations in the internal and
external background spacetime of a slowly rotating magnetized neutron star. The
star is considered isolated and in vacuum, with a dipolar magnetic field not
aligned with the axis of rotation. With respect to a flat spacetime solution,
general relativity introduces corrections related both to the monopolar and the
dipolar parts of the gravitational field. In particular, we show that in the
case of infinite electrical conductivity general relativistic corrections due
to the dragging of reference frames are present, but only in the expression for
the electric field. In the case of finite electrical conductivity, however,
corrections due both to the spacetime curvature and to the dragging of
reference frames are shown to be present in the induction equation. These
corrections could be relevant for the evolution of the magnetic fields of
pulsars and magnetars. The solutions found, while obtained through some
simplifying assumption, reflect a rather general physical configuration and
could therefore be used in a variety of astrophysical situations.

</DOC>
<DOC>
<DOCNO> 13427 </DOCNO>
Performance of cryogenic microbolometers and calorimeters with on-chip


  Astronomical observations of cosmic sources in the far-infrared and X-ray
bands require extreme sensitivity. The most sensitive detectors are cryogenic
bolometers and calorimeters operating typically at about 100 mK. The last stage
of cooling (from 300 mK to 100 mK) often poses significant difficulties in
space-borne experiments, both in system complexity and reliability. We address
the possibility of using refrigeration based on normal
metal/insulator/superconductor (NIS) tunnel junctions as the last stage cooler
for cryogenic thermal detectors. We compare two possible schemes: the direct
cooling of the electron gas of the detector with the aid of NIS tunnel
junctions and the indirect cooling method, when the detector lattice is cooled
by the refrigerating system, while the electron gas temperature is decreased by
electron-phonon interaction. The latter method is found to allow at least an
order of magnitude improvement in detector noise equivalent power, when
compared to the direct electron cooling.

</DOC>
<DOC>
<DOCNO> 80653 </DOCNO>
Lattice Gauge Theories and the AdS/CFT Correspondence


  This is the write-up of a set of lectures on the comparison between Lattice
Gauge Theories and AdS/CFT results for the non-perturbative behaviour of
non-supersymmetric Yang Mills theories. These notes are intended for students
which are assumed not to be experts in L.G.T. For this reason the first part is
devoted to a pedagogical introduction to the Lattice regularization of QCD. In
the second part we discuss some basic features of the AdS/CFT correspondence
and compare the results obtained in the non-supersymmetric limit with those
obtained on the Lattice. We discuss in particular the behaviour of the string
tension and of the glueball spectrum. Lectures delivered at the School of
Theoretical Physics (S.N.F.T.), Parma, September 1999.

</DOC>
<DOC>
<DOCNO> 101586 </DOCNO>
Deformed Heisenberg algebras, a Fock-space representation and the


  We describe generally deformed Heisenberg algebras in one dimension. The
condition for a generalized Leibniz rule is obtained and solved. We analyze
conditions under which deformed quantum-mechanical problems have a Fock-space
representation. One solution of these conditions leads to a q-deformed
oscillator already studied by Lorek et al., and reduces to the harmonic
oscillator only in the infinite-momentum frame. The other solution leads to the
Calogero model in ordinary quantum mechanics, but reduces to the harmonic
oscillator in the absence of deformation.

</DOC>
<DOC>
<DOCNO> 151409 </DOCNO>
Sphaleron glueballs in NBI theory with symmetrized trace


  We derive a closed expression for the SU(2) Born-Infeld action with the
symmetrized trace for static spherically symmetric purely magnetic
configurations. The lagrangian is obtained in terms of elementary functions.
Using it, we investigate glueball solutions to the flat space NBI theory and
their self-gravitating counterparts. Such solutions, found previously in the
NBI model with the 'square root - ordinary trace' lagrangian, are shown to
persist in the theory with the symmetrized trace lagrangian as well. Although
the symmetrized trace NBI equations differ substantially from those of the
theory with the ordinary trace, a qualitative picture of glueballs remains
essentially the same. Gravity further reduces the difference between solutions
in these two models, and, for sufficiently large values of the effective
gravitational coupling, solutions tends to the same limiting form. The black
holes in the NBI theory with the symmetrized trace are also discussed.

</DOC>
<DOC>
<DOCNO> 101944 </DOCNO>
Canonical path integral quantization of the finite dimensional systems


  The path integral formulation of constrained systems leads to obtain the
equations of motion as total differential equations in many variables. If these
equations are integrable then one can constuct a valid and a canonical phase
space coordinates. The path integral is obtained as an integration over the
canonical phase space coordinates. This approach is applied to obtain the path
integral for three singular systems and it is shown that in our formulation
there is no need to distinguish between first and second-class constraints, no
need for fixing any gauge, as will as no need to enlarge the phase space.

</DOC>
<DOC>
<DOCNO> 121310 </DOCNO>
Star Formation in Viscous Galaxy Disks


  The Lin and Pringle model (1987) of galactic disk formation postulates that
if star formation proceeds on the same timescale as the viscous redistribution
of mass and angular momentum in disk galaxies, then the stars attain an
exponential density profile. Their claim is that this result holds generally:
regardless of the disk galaxy's initial gas and dark matter distribution and
independent of the nature of the viscous processes acting in the disk. We
present new results from a set of 2D hydro-simulations which investigate their
analytic result.

</DOC>
<DOC>
<DOCNO> 102833 </DOCNO>
Matroids, motives and conjecture of Kontsevich


  Let G be a finite connected graph. The Kirchhoff polynomial of G is a certain
homogeneous polynomial whose degree is equal to the first betti number of G.
These polynomials appear in the study of electrical circuits and in the
evaluation of Feynman amplitudes. Motivated by work of D. Kreimer and D. J.
Broadhurst associating multiple zeta values to certain Feynman integrals,
Kontsevich conjectured that the number of zeros of a Kirchhoff polynomial over
the field with q elements is always a polynomial function of q. We show that
this conjecture is false by relating the schemes defined by Kirchhoff
polynomials to the representation spaces of matroids. Moreover, using Mnev's
universality theorem, we show that these schemes essentially generate all
arithmetic of schemes of finite type over the integers.

</DOC>
<DOC>
<DOCNO> 9591 </DOCNO>
A new approach to the study of the ground-state properties of 2D Ising


  A new approach known as flat histogram method is used to study the +/-J Ising
spin glass in two dimensions. Temperature dependence of the energy, the
entropy, and other physical quantities can be easily calculated and we give the
results for the zero-temperature limit. For the ground-state energy and entropy
of an infinite system size, we estimate e0 = -1.4007 +/- 0.0085 and s0 = 0.0709
+/- 0.006, respectively. Both of them agree well with previous calculations.
The time to find the ground-states as well as the tunneling times of the
algorithm are also reported and compared with other methods.

</DOC>
<DOC>
<DOCNO> 72232 </DOCNO>
Mass determination of the lightest supersymmetric partner (C-boson and


  %auto-ignore This paper has been withdrawn by the author(s) because somebody
do not agree with my idea.

</DOC>
<DOC>
<DOCNO> 118540 </DOCNO>
Grain Survival in Supernova Remnants and Herbig-Haro Objects


  By using the flux ratio [FeII]8617/[OI]6300, we demonstrate that most of the
interstellar dust grains survive in shocks associated with supernova remnants
and Herbig-Haro objects. The [FeII]/[OI] flux ratio is sensitive to the
gas-phase Fe/O abundance ratio, but is insensitive to the ionization state,
temperature, and density of the gas. We calculate the [FeII]/[OI] flux ratio in
shocks, and compare the results with the observational data. When only 20% of
iron is in the gas phase, the models reproduce most successfully the
observations. This finding is in conflict with the current consensus that
shocks destroy almost all the grains and 100% of metals are in the gas phase.
We comment on previous works on grain destruction, and discuss why grains are
not destroyed in shocks.

</DOC>
<DOC>
<DOCNO> 123113 </DOCNO>
ASCA Discovery of Diffuse 6.4 keV Emission Near the Sgr C Complex: A New


  We present an ASCA discovery of diffuse hard X-ray emission from the Sgr C
complex with its peak in the vicinity of the molecular cloud core. The X-ray
spectrum is characterized by a strong 6.4-keV line and large absorption. These
properties suggest that Sgr C is a new X-ray reflection nebula which emits
fluorescent and scattered X-rays via irradiation from an external X-ray source.
We found no adequately bright source in the immediate Sgr C vicinity to fully
account for the fluorescence. The irradiating source may be the Galactic
nucleus Sgr A*, which was brighter in the past than it is now as is suggested
from observations of the first X-ray reflection nebula Sgr B2.

</DOC>
<DOC>
<DOCNO> 69476 </DOCNO>
Masses and Mixings from Neutrino Beams pointing to Neutrino Telescopes


  We discuss the potential to determine leading oscillation parameters, the
value and the sign of \Delta m^2_{31}, as well as the magnitude of \sin^2
2\theta_{13} using a conventional wide band neutrino beam pointing to water or
ice Cherenkov neutrino detectors known as ``Neutrino Telescopes''. We find that
precision measurements of \Delta m^2_{31} and \theta_{23} are possible and
that, even though it is not possible to discriminate between charges in the
detector, there is a remarkably good sensitivity to the mixing angle
\theta_{13} and the sign of \Delta m^2_{31}.

</DOC>
<DOC>
<DOCNO> 150853 </DOCNO>
Dimensional Transmutation and Dimensional Regularization in Quantum


  This is the first in a series of papers addressing the phenomenon of
dimensional transmutation in nonrelativistic quantum mechanics within the
framework of dimensional regularization. Scale-invariant potentials are
identified and their general properties are derived. A strategy for dimensional
renormalization of these systems in the strong-coupling regime is presented,
and the emergence of an energy scale is shown, both for the bound-state and
scattering sectors. Finally, dimensional transmutation is explicitly
illustrated for the two-dimensional delta-function potential.

</DOC>
<DOC>
<DOCNO> 13038 </DOCNO>
Wedge filling, cone filling and the strong fluctuation regime


  Interfacial fluctuation effects occuring at wedge and cone filling
transitions are investigated and shown to exhibit very different
characteristics. For both geometries we show how the conditions for observing
critical (continuous) filling are much less restrictive than for critical
wetting, which is known to require fine tuning of the Hamaker constants. Wedge
filling is critical if the wetting binding potential does not exhibit a local
maximum, whilst conic filling is critical if the integrated strength of the
potential is attractive. This latter scenario is particularly encouraging for
future experimental studies. Using mean-field and effective Hamiltonian
approaches, which allow for breather-mode fluctuations which translate the
interface up and down the sides of the confining geometry, we are able to
completely classify the possible critical behaviour (for purely thermal
disorder). For the three dimensional wedge, the interfacial fluctuations are
very strong and characterised by a universal roughness critical exponent
$\nu_{\perp} =1/4$ independent of the range of the forces. For the physical
dimensions d=2 and d=3, we show that the influence of the cone geometry on the
fluctuations at critical filling is to mimic the analogous interfacial
behaviour occuring at critical wetting in the strong-fluctuation regime. In
particular, for d=3 and for quite arbitary choices of intermolecular potential,
the filling height and roughness show the same critical properties as those
predicted for three dimensional critical wetting with short-ranged forces in
the large wetting parameter ($\omega>2$) regime.

</DOC>
<DOC>
<DOCNO> 8816 </DOCNO>
Dynamics of Rough Interfaces in Chemical Vapor Deposition: Experiments


  We study the surface dynamics of silica films grown by low pressure chemical
vapor deposition. Atomic force microscopy measurements show that the surface
reaches a scale invariant stationary state compatible with the
Kardar-Parisi-Zhang (KPZ) equation in three dimensions. At intermediate times
the surface undergoes an unstable transient due to shadowing effects. By
varying growth conditions and using spectroscopic techniques, we determine the
physical origin of KPZ scaling to be a low value of the surface sticking
probability, related to the surface concentration of reactive groups. We
propose a stochastic equation that describes the qualitative behavior of our
experimental system.

</DOC>
<DOC>
<DOCNO> 12394 </DOCNO>
Anomalous modes drive vortex dynamics in confined Bose-Einstein


  The dynamics of vortices in trapped Bose-Einstein condensates are
investigated both analytically and numerically. In axially symmetric traps, the
critical rotation frequency for the metastability of an isolated vortex
coincides with the largest vortex precession frequency (or anomalous mode) in
the Bogoliubov excitation spectrum. As the condensate becomes more elongated,
the number of anomalous modes increases. The largest frequency of these modes
exceeds both the thermodynamic critical frequency and the nucleation frequency
at which vortices are created dynamically. Thus, anomalous modes describe not
only the critical rotation frequency for creation of the first vortex in an
elongated condensate but also the vortex precession in a single-component
spherical condensate.

</DOC>
<DOC>
<DOCNO> 69188 </DOCNO>
Phenomenology of Neutrino Oscillations at a Neutrino Factory


  It is shown in the three flavor framework that neutrino factories enable us
to measure some of the oscillation parameters, such as the sign of $\Delta
m_{32}^2$, $\theta_{13}$, $\delta$. Some efforts are made to determine the
parameters (the muon energy and the neutrino path length) of a neutrino factory
to optimize the signals.

</DOC>
<DOC>
<DOCNO> 99551 </DOCNO>
Compact Stein surfaces with boundary as branched covers of $\B^4$


  We prove that Stein surfaces with boundary coincide up to orientation
preserving diffeomorphisms with simple branched coverings of $\B^4$ whose
branch set is a positive braided surface. As a consequence, we have that a
smooth oriented 3-manifold is Stein fillable iff it has a positive open-book
decomposition.

</DOC>
<DOC>
<DOCNO> 178593 </DOCNO>
Formation of Few-Body Clusters in Nuclear Matter


  Starting from a suitably modified three-body equation to include dominant
medium effects such as self energy corrections and Pauli blocking I present
results on several observables relevant for the formation of light clusters in
a heavy ion collision at moderate energies. Properly taking into account the
medium leads to the Mott effect, larger reaction rates, in turn, faster time
scales for the deuteron life time and chemical relaxation time. Within a
Boltzmann-Uehling-Uhlenbeck approach to simulate the heavy ion reactions, also
the total number of deuterons and the energy spectrum are significantly changed
due to medium effects in the elementary cross sections entering into the
collision integrals.

</DOC>
<DOC>
<DOCNO> 71582 </DOCNO>
Recent Developments in Superstring Theory


  The talk contains a brief introduction string theory, followed by a
discussion of some of the recent developments.

</DOC>
<DOC>
<DOCNO> 116328 </DOCNO>
Interfering with Interference: a Pancharatnam Phase Polarimeter


  A simple variation of the traditional Young's double slit experiment can
demonstrate several subtleties of interference with polarized light, including
Berry and Pancharatnam's phase. Since the position of the fringes depends on
the polarization state of the light at the input, the apparatus can also be
used to measure the light's polarization without a quarter-wave plate or an
accurate measurement of the light's intensity. In principle this technique can
be used for any wavelength of photon as long as one can effectively polarize
the incoming radiation.

</DOC>
<DOC>
<DOCNO> 123109 </DOCNO>
Thermal Relaxation in Young Neutron Stars


  The internal properties of the neutron star crust can be probed by observing
the epoch of thermal relaxation. After the supernova explosion, powerful
neutrino emission quickly cools the stellar core, while the crust stays hot.
The cooling wave then propagates through the crust, due to its finite thermal
conductivity. When the cooling wave reaches the surface (age 10-100 yr), the
effective temperature drops sharply from 250 eV to 30 or 100 eV, depending on
the cooling model. The crust relaxation time is sensitive to the (poorly known)
microscopic properties of matter of subnuclear density, such as the heat
capacity, thermal conductivity, and superfluidity of free neutrons. We
calculate the cooling models with the new values of the electron thermal
conductivity in the inner crust, based on a realistic treatment of the shapes
of atomic nuclei. Superfluid effects may shorten the relaxation time by a
factor of 4. The comparison of theoretical cooling curves with observations
provides a potentially powerful method of studying the properties of the
neutron superfluid and highly unusual atomic nuclei in the inner crust.

</DOC>
<DOC>
<DOCNO> 10853 </DOCNO>
Network of Hydrogen Bonds as a Medium for DNA Interaction in Solvents


  We suggest that the DNA molecules could form the cholesteric phase owing to
an interaction mediated by the network of the hydrogen bonds (H-network) in the
solvent. The model admits of the dependence of the optical activity of the
solution on the concentration of the PEG, and the change in the sense of the
cholesteric twist due to the intercalation by the daunomicyn. Using the
experimental data for the cholesteric phase of the DNA dispersion, we obtain a
rough estimate for the energy given by our model, and show that it should be
taken into account as well as the energy due to the steric repulsion, van der
Waals, and electrostatic forces, generally used for studying the DNA molecules.
The elastic constant of the H-network generating the interaction between the
DNA molecules is determined by the energy due to the proton's vibration in the
hydrogen bonds.

</DOC>
<DOC>
<DOCNO> 12748 </DOCNO>
Ground State Phase Diagrams of Frustrated Spin-S XXZ Chains: Chiral


  The ground-state phase diagram of the frustrated spin-S XXZ chain with the
competing nearest- and next-nearest-neighbor antiferromagnetic couplings is
studied numerically by using the density-matrix renormalization-group method
for the cases of S = 1/2, 3/2, and 2. We are paricularly interested in the
possible gapless and gapped chiral phases, in which the chirality \kappa_l =
S_l^x S_{l+1}^y - S_l^y S_{l+1}^x exhibits a finite long-range order whereas
the spin correlation decays either algebraically or exponentially. We show that
the gapless chiral phase appears in a broad region of the phase diagram for
general S. By contrast, the gapped chiral phase is found for integer S in a
narrow region of the phase diagram, while it has not been identified for
half-odd integer S within our numerical accuracy. By combining the results with
our previous result for S = 1, we discuss the S-dependence of the phase
diagram. The prediction from a bosonization analysis on the decay exponent of
the spin correlation is verified.

</DOC>
<DOC>
<DOCNO> 102771 </DOCNO>
Invitation to higher local fields, Part I, section 6: Topological Milnor


  Certain topologies on Milnor K-groups of higher local fields K are studied.
These are related to the topology on the multiplicative group and important for
explicit higher local class field theory. The structure of the quotient of
Milnor K-groups modulo the intersection of all neighbourhoods of zero is
described.

</DOC>
<DOC>
<DOCNO> 71994 </DOCNO>
Direct CP-asymmetry in Inclusive Rare B-decays in 2HDM


  The direct CP-asymmetry in the inclusive $B \to X_d \gamma$ and $B \to X_d
e^+ e^ - $ decays is investigated in the two-Higgs doublet extension of the
Standard Model (2HDM). The investigation is performed in the lowest
non-vanishing order of the perturbation theory using the existing restrictions
on the 2HDM parameters space. It is shown that the direct CP-asymmetry in the
$B \to X_d \gamma$ decay can deviate significantly from the Standard Model
predictions. In the presence of only one source of CP-violation (the CKM matrix
weak phase) $a_{CP}(B \to X_d \gamma)$ can have the sign opposite to that in
the SM. The new source of CP-violation can make $|a_{CP}(B \to X_d \gamma)|$
arbitrary small (unlike the SM case) and hence unmeasurable. Quantitatively,
the obtained results suffer from the uncertainty of the choice of
renormalization scale. As for the $B \to X_d e^+ e^ - $ rate asymmetry, its
renormalization scale dependence in the lowest non-vanishing order does not
allow to conclude if this quantity is efficient for testing New Physics beyond
the Standard Model.

</DOC>
<DOC>
<DOCNO> 7748 </DOCNO>
Interaction-induced localization-delocalization transition in the


  We report on numerical studies of the energy spectrum and the localization
properties in the double-layer quantum Hall system at $\nu = 1$. The Coulomb
interaction is treated by the Hartree-Fock approximation, and the localization
properties in the presence of disorder are studied by evaluating participation
ratios for the Hartree-Fock eigenfunctions. We show that the extended states
seem to exist only near each center of the two subbands split by the
exchange-enhanced energy gap. It is also shown that the self-consistent
orbitals whose energies are close to the Fermi energy appear to become extended
together with the reduction in the energy gap as the layer separation
increases. The collapse of the energy gap expected from our results is
consistent with the incompressible-compressible transition observed in recent
experiments, and the change of the localization properties near the Fermi
energy can explain the disappearance of the quantum Hall effect for large layer
separations very well.

</DOC>
<DOC>
<DOCNO> 84255 </DOCNO>
On existence of mini-boson stars


  We prove the existence of a countable family of globally regular solutions of
spherically symmetric Einstein-Klein-Gordon equations. These solutions, known
as mini-boson stars, were discovered numerically many years ago.

</DOC>
<DOC>
<DOCNO> 12799 </DOCNO>
Fractional transport equations for Levy stable processes


  The influence functional method of Feynman and Vernon is used to obtain a
quantum master equation for a Brownian system subjected to a Levy stable random
force. The corresponding classical transport equations for the Wigner function
are then derived, both in the limit of weak and strong friction. These are
fractional extensions of the Klein-Kramers and the Smoluchowski equations. It
is shown that the fractional character acquired by the position in the
Smoluchowski equation follows from the fractional character of the momentum in
the Klein-Kramers equation. Connections among fractional transport equations
recently proposed are clarified.

</DOC>
<DOC>
<DOCNO> 10889 </DOCNO>
Spin glasses without time-reversal symmetry and the absence of a genuine


  We study the three-spin model and the Ising spin glass in a field using
Migdal-Kadanoff approximation. The flows of the couplings and fields indicate
no phase transition, but they show even for the three-spin model a slow
crossover to the asymptotic high-temperature behaviour for strong values of the
couplings. We also evaluated a quantity that is a measure of the degree of
non-self-averaging, and we found that it can become large for certain ranges of
the parameters and the system sizes. For the spin glass in a field the maximum
of non-self-averaging follows for given system size a line that resembles the
de Almeida-Thouless line. We conclude that non-self-averaging found in
Monte-Carlo simulations cannot be taken as evidence for the existence of a
low-temperature phase with replica-symmetry breaking. Models similar to the
three-spin model have been extensively discussed in order to provide a
description of structural glasses. Their theory at mean-field level resembles
the mode-coupling theory of real glasses. At that level the one-step replica
symmetry approach breaking predicts two transitions, the first transition being
dynamical and the second thermodynamical. Our results suggest that in real
finite dimensional glasses there will be no genuine transitions at all, but
that some features of mean-field theory could still provide some useful
insights.

</DOC>
<DOC>
<DOCNO> 117317 </DOCNO>
Several New Cases Violating Time Reversal Symmetry In the Processes of


  It is pointed that we now actually have no enough proofs to prove that time
reversal symmetry is universally obeyed in the processes of particle
interactions. The analyses show that the time reversal symmetry is obviously
violated at least in the decay processes of particles, especially in the decay
processes of strange particles, and some resonance states with only one middle
resonance particle to appear, as well as the annihilation processes of particle
pairs. So the phenomena of violating time reversal symmetry may exist commonly
in the interaction processes between particles.

</DOC>
<DOC>
<DOCNO> 71338 </DOCNO>
The flavor of neutrinos in muon decays at a neutrino factory and the


  The accurate prediction of the neutrino beam produced in muon decays and the
absence of opposite helicity contamination for a particular neutrino flavor
make a future neutrino factory the ideal place to look for the lepton flavor
violating (LFV) decays of the kind $\mu^+\ra e^+\nuebar\numu$ and lepton number
violating (LNV) processes like $\mu^-\ra e^-\nue\numu$. Excellent sensitivities
can be achieved using a detector capable of muon and/or electron identification
with charge discrimination. This would allow to set experimental limits that
improve current ones by more than two orders of magnitude and test the
hypothesis that the LSND excess is due to such anomalous decays, rather than
neutrino flavor oscillations in vacuum.

</DOC>
<DOC>
<DOCNO> 10196 </DOCNO>
Self-Organized Criticality in a Transient System


  A simple model economy with locally interacting producers and consumers is
introduced. When driven by extremal dynamics, the model self-organizes {\em
not} to an attractor state, but to an asymptote, on which the economy has a
constant rate of deflation, is critical, and exhibits avalanches of activity
with power-law distributed sizes. This example demonstrates that self-organized
critical behavior occurs in a larger class of systems than so far considered:
systems not driven to an attractive fixed point, but, e.g., an asymptote, may
also display self-organized criticality.

</DOC>
<DOC>
<DOCNO> 121510 </DOCNO>
The Ultra-Luminous IR Galaxy Population


  We summarize results from an on-going Hubble Space Telescope (HST) survey of
a large sample of ULIRGs (Ultra-Luminous IR Galaxies). New ground-based
multi-fiber spectroscopic observations are now being obtained to complement the
HST data and to assist in the interpretation of these complex objects.

</DOC>
<DOC>
<DOCNO> 170049 </DOCNO>
Adiabatic Elimination in Compound Quantum Systems with Feedback


  Feedback in compound quantum systems is effected by using the output from one
sub-system (``the system'') to control the evolution of a second sub-system
(``the ancilla'') which is reversibly coupled to the system. In the limit where
the ancilla responds to fluctuations on a much shorter time scale than does the
system, we show that it can be adiabatically eliminated, yielding a master
equation for the system alone. This is very significant as it decreases the
necessary basis size for numerical simulation and allows the effect of the
ancilla to be understood more easily. We consider two types of ancilla: a
two-level ancilla (e.g. a two-level atom) and an infinite-level ancilla (e.g.
an optical mode). For each, we consider two forms of feedback: coherent (for
which a quantum mechanical description of the feedback loop is required) and
incoherent (for which a classical description is sufficient). We test the
master equations we obtain using numerical simulation of the full dynamics of
the compound system. For the system (a parametric oscillator) and feedback
(intensity-dependent detuning) we choose, good agreement is found in the limit
of heavy damping of the ancilla. We discuss the relation of our work to
previous work on feedback in compound quantum systems, and also to previous
work on adiabatic elimination in general.

</DOC>
<DOC>
<DOCNO> 116596 </DOCNO>
Bell's theorem, entanglement, and common sense


  A simple analogy to understand the quantum-mechanical entanglement within
local-realistic world is presented.

</DOC>
<DOC>
<DOCNO> 11694 </DOCNO>
Anomalous Sliding Friction and Peak Effect near the Flux Lattice Melting


  Recent experiments have revealed a giant "peak effect" in ultrapure high
$T_c$ superconductors. Moreover, the new data show that the peak effect
coincides exactly with the melting transition of the underlying flux lattice.
In this work, we show using dynamical scaling arguments that the friction due
to the pinning centers acting on the flux lattice develops a singularity near a
continuous phase transition and can diverge for many systems. The magnitude of
the nonlinear sliding friction of the flux lattice scales with this atomistic
friction. Thus, the nonlinear conductance should diverge for a true continuous
transition in the flux lattice or peak at a weakly first order transition or
for systems of finite size.

</DOC>
<DOC>
<DOCNO> 70503 </DOCNO>
Wilson Lines Near the Light Cone


  We study the dynamics of Wilson lines near the light cone in QCD. Lattice
simulations of the near light cone Hamiltonian in SU(2) show that the
correlation mass at strong coupling vanishes at intermediate coupling, which
signals a continuum transition on the light cone. We point out the possible
relevance of this mass for high energy scattering.

</DOC>
<DOC>
<DOCNO> 118143 </DOCNO>
From Historical Perspectives to Some Modern Possibilities


  A historical perspective on the study of asymmetries in planetary nebulae
(PNs) is presented. We also describe our ongoing work in high resolution
spectroscopy of planetaries, and discuss some likely future directions for the
study of asymmetrical PNs.

</DOC>
<DOC>
<DOCNO> 122182 </DOCNO>
Preliminary Spectral Analysis of the Type II Supernova 1999em


  We have calculated fast direct spectral model fits to two early-time spectra
of the Type-II plateau SN 1999em, using the SYNOW synthetic spectrum code. The
first is an extremely early blue optical spectrum and the second a combined HST
and optical spectrum obtained one week later. Spectroscopically this supernova
appears to be a normal Type II and these fits are in excellent agreement with
the observed spectra. Our direct analysis suggests the presence of enhanced
nitrogen. We have further studied these spectra with the full NLTE general
model atmosphere code PHOENIX. While we do not find confirmation for enhanced
nitrogen (nor do we rule it out), we do require enhanced helium. An even more
intriguing possible line identification is complicated Balmer and He I lines,
which we show falls naturally out of the detailed calculations with a shallow
density gradient. We also show that very early spectra such as those presented
here combined with sophisticated spectral modeling allows an independent
estimate of the total reddening to the supernova, since when the spectrum is
very blue, dereddening leads to changes in the blue flux that cannot be
reproduced by altering the ``temperature'' of the emitted radiation. These
results are extremely encouraging since they imply that detailed modeling of
early spectra can shed light on both the abundances and total extinction of SNe
II, the latter improving their utility and reliability as distance indicators.

</DOC>
<DOC>
<DOCNO> 39785 </DOCNO>
Discovering Ultra High Energy Neutrinos by Horizontal and Upward tau


  Ultra high energy neutrinos UHE neutrino Tau, anti-neutrino Tau,
anti-neutrino electron at PeVs, and higher energy may induce tau air-showers
whose detectability is million to billion times amplified by their secondaries.
We considered UHE nu_{tau}- N and UHE bar\nu_{e}- e interactions beyond
mountains as a source of such horizontal amplified Tau air-showers. We also
consider vertical upward UHE nu_{tau}-N interaction on Earth crust leading to
UHE Tau airshowers {UPTAUS} or at the horizont edges {HORTAUS} and their
beaming toward high mountains gamma, X, Cherenkov detectors on mountains. We
show their detectability. We notice that such rare upward Tau air-shower,
UPTAUS and HORTAUS, may hit even nearby airlines, ballons, satellite and flash
them by short diluted gamma-burst at the edge of Gamma Ray Observatory (GRO)
detection threshold. We suggest the identification of these events with recent
discovered (BATSE) Terrestrial Gamma Flashes and we claim their probable UHE
Tau by UHE nu_\tau origin. From these data approximated UHE nu_tau flux and
Delta m_{nu_mu \nu_tau} lower bound are derived. Known X-gamma-{TeV} active
galactic and extragalactic sources have been identified in most TGF arrival
directions. Maximal EGRET activity in galactic Center overlap with maximal TGF
flux. The UHECR AGASA an-isotropy at 10^{18} eV shows also possible
correlations with TGF events. The unique UHECR triplet in AGASA clustering,
pointing toward BL Lac 1ES0806+524, finds, within its error box, a
corresponding TGF event, BATSE (Trigger 2444). Finally a partial TGF Galactic
signature, combined with above correlations suggests an astrophysical tau
origin of TGF events.

</DOC>
<DOC>
<DOCNO> 122877 </DOCNO>
Spectroscopy of Ultra Steep Spectrum Radio Sources


  We present optical spectroscopy of 62 objects selected from several samples
of ultra steep spectrum (USS) radio sources. 46 of these are from our primary
catalog, consisting of 669 sources with radio spectral indices alpha < -1.30
(S_nu ~ nu^alpha); this first spectroscopic sub-sample was selected on the
basis of their faint optical and near-IR identifications. Most are identified
as narrow-lined radio galaxies with redshifts ranging from z=0.25 to z=5.19.
Ten objects are at z>3, nearly doubling the number of such sources known to
date. Four of the USS radio sources are identified with quasars, of which at
least three have very red spectral energy distributions. The source TN
J0936-2242 is identified with an extremely red object (ERO, R-K>5); both it and
a close companion are at z=1.479. The spectrum of the ERO closely resembles
that of previously discovered radio galaxies at z~1.5. Five sources show
continuum emission, but fail to show any clear emission or absorption features,
despite integrations of ~1 h with the Keck telescope. We suggest that these
objects could be (i) radio galaxies with faint emission lines in the ``redshift
desert'' at 1.5 <~ z <~ 2.3, (ii) radio galaxies with an obscured AGN, which
are dominated by a stellar continuum observed with insufficient S/N, or (iii)
pulsars. Three radio sources identified with faint objects in the K-band images
remain undetected in 50-90 min spectroscopic integrations with the Keck
telescope, and are possible z>7 candidates.

</DOC>
<DOC>
<DOCNO> 69061 </DOCNO>
Charge Asymmetries in charm photoproduction


  Charm quarks are expected to be produced mainly by the photon-gluon fusion
mechanism in photon-Nucleon interactions. However, a small part of the total
charm cross section originates in similar processes to those appearing in charm
hadroproduction through the resolved (hadronic) component of the photon.
Although the contribution of the resolved part of the photon is small at fixed
target energies, it can help to understand the small but sizeable charge
asymmetries measured in charm hadron photoproduction experiments.

</DOC>
<DOC>
<DOCNO> 100187 </DOCNO>
Intertwining operator superalgebras and vertex tensor categories for


  We construct the intertwining operator superalgebras and vertex tensor
categories for the N=2 superconformal unitary minimal models and other related
models.

</DOC>
<DOC>
<DOCNO> 119043 </DOCNO>
The Initial Mass Function of Low-Mass Stars and Brown Dwarfs in Young


  We have obtained images of the Trapezium Cluster (140" x 140"; 0.3 pc x 0.3
pc) with the Hubble Space Telescope Near-Infrared Camera and Multi-Object
Spectrometer (NICMOS). Combining these data with new ground-based K-band
spectra (R=800) and existing spectral types and photometry and the models of
D'Antona & Mazzitelli, we find that the distributions of ages of comparable
samples of stars in the Trapezium, rho Oph, and IC 348 indicate median ages of
\~0.4 Myr for the first two regions and ~1-2 Myr for the latter. The low-mass
IMFs in these sites of clustered star formation are similar over a wide range
of stellar densities and other environmental conditions. With current data, we
cannot rule out modest variations in the substellar mass functions among these
clusters. We then make the best estimate of the true form of the IMF in the
Trapezium by using the evolutionary models of Baraffe et al. and an empirically
adjusted temperature scale and compare this mass function to recent results for
the Pleiades and the field. All of these data are consistent with an IMF that
is flat or rises slowly from the substellar regime to about 0.6 Msun, and then
rolls over into a power law that continues from about 1 Msun to higher masses
with a slope similar to or somewhat larger than the Salpeter value of 1.35. For
the Trapezium, this behavior holds from our completeness limit of ~0.02 Msun
and probably, after a modest completeness correction, even from 0.01-0.02 Msun.
These data include ~50 likely brown dwarfs. We test the predictions of theories
of the IMF against various properties of the observed IMF.

</DOC>
<DOC>
<DOCNO> 121101 </DOCNO>
High redshift CO line emission: perspectives


  Although about a dozen high redshift (z larger than 2) starburst galaxies
have been recently detected in the CO lines, spectroscopic detections of
molecular gas of very young galaxies are still very difficult. The CO lines are
usually optically thick, which limits greatly the increase of emission with
redshift, as observed for the dust continuum. However the future instruments
(LMT, ALMA, etc..) will allow large progress in this domain, and perspectives
are discussed. Computations are based on a simple extrapolation of what is
known of starbursting galaxies at lower redshift.

</DOC>
<DOC>
<DOCNO> 71263 </DOCNO>
U-Spin Symmetry in Doubly Cabibbo-Suppressed Charmed Meson Decays


  We prove a U-spin amplitude triangle relation among doubly Cabibbo-suppressed
(DCS) charmed meson decays, $D^0\to K^+\pi^-, D^0 \to K^0\pi^0$ and $D^+_s \to
K^0 K^+$, congruent to an isospin relation among corresponding Cabibbo-favored
(CF) decays. U-spin breaking in relative phases between CF and DCS amplitudes
affects time-dependent studies of $D^0-\od$ mixing. Comparison of final state
phase patterns in DCS and CF amplitude triangles, which can shed some light on
these phases, is carried out in a phenomenological framework incorporating
resonance contributions.

</DOC>
<DOC>
<DOCNO> 7970 </DOCNO>
Universal Statistics of Inviscid Burgers Turbulence in Arbitrary


  We investigate the non-perturbative results of multi-dimensional forced
Burgers equation coupled to the continuity equation. In the inviscid limit, we
derive the exact exponents of two-point density correlation functions in the
universal region in arbitrary dimensions. We then find the universal generating
function and the tails of the probability density function (PDF) for the
longitudinal velocity difference. Our results exhibit that in the inviscid
limit, density fluctuations affect the master equation of the generating
function in such a way that we can get a positive PDF with the well-known
exponential tail. The exponent of the algebraic tail is derived to be -5/2 in
any dimension. Finally we observe that various forcing spectrums do not alter
the power law behaviour of the algebraic tail in these dimensions, due to a
relation between forcing correlator exponent and the exponent of the two-point
density correlation function.

</DOC>
<DOC>
<DOCNO> 68690 </DOCNO>
Frame-Independence of Exclusive Amplitudes in the Light-Front


  While the particle-number-conserving convolution formalism established in the
Drell-Yan-West reference frame is frequently used to compute exclusive
amplitudes in the light-front quantization, this formalism is limited to only
those frames where the light-front helicities are not changed and the good
(plus) component of the current remains unmixed. For an explicit demonstration
of such criteria, we present the relations between the current matrix elements
in the two typical reference frames used for calculations of the exclusive
amplitudes, i.e. the Drell-Yan-West and Breit frames and investigate both
pseudoscalar and vector electromagnetic currents in detail. We find that the
light-front helicities are unchanged and the good component of the current does
not mix with the other components of the current under the transformation
between these two frames. Thus, the pseudoscalar and vector form factors
obtained by the diagonal convolution formalism in both frames must indeed be
identical. However, such coincidence between the Drell-Yan-West and Breit
frames does not hold in general. We give an explicit example in which the
light-front helicities are changed and the plus component of the current is
mixed with other components under the change of reference frame. In such a
case, the relationship between the frames should be carefully analyzed before
the established convolution formalism in the Drell-Yan-West frame is used.

</DOC>
<DOC>
<DOCNO> 120847 </DOCNO>
The Edinburgh/Durham Southern Galaxy Catalogue - IX. The Galaxy


  We announce here the public availability of the Edinburgh/Durham Southern
Galaxy Catalogue (EDSGC, http://www.edsgc.org). This objective galaxy catalogue
was constructed using the COSMOS micro-densitometer at the Royal Observatory
Edinburgh and constitutes one of the largest digitized galaxy surveys currently
in existence. The EDSGC contains a total of 1,495,877 galaxies (each with 27
image parameters) covering an contiguous area of 1182 sq deg centered on the
South Galactic Pole. The data consists of photographic bj magnitudes calibrated
via CCD sequences which provide a plate-to-plate accuracy of bj~0.1. Extensive
external checks have demonstrated that the global EDSGC photometry is free of
large-scale systematic gradients and is therefore, ideal for studying the
distribution of galaxies on large angular scales. Independent spectroscopy of
EDSGC galaxies has shown that the accuracy of the star-galaxy separation is
consistent with earlier visual checks and that only 12% of EDSGC galaxies are
potentially mis-classified. This paper is intended to provide a summary of the
essential details of the catalogue's design and construction as well as provide
a brief summary of the main scientific achievements using the EDSGC over the
last ten years.

</DOC>
<DOC>
<DOCNO> 71468 </DOCNO>
Cosmic ray photodisintegration and the knee of the spectrum


  We explore in some detail the scenario proposed to explain the observed knee
of the cosmic ray (CR) spectrum as due to the effects of photodisintegration of
the CR nuclei by interactions with optical and soft UV photons in the source
region. We show that the photon column densities needed to explain the
experimental data are significantly lower than those obtained in previous
estimations which neglected multinucleon emission in the photodisintegration
process. We also treat more accurately the photodisintegration thresholds, we
discuss the effects of photopion production processes and the neutron escape
mechanism, identifying the physical processes responsible for the qualitative
features of the results. This scenario would require the CR nuclei to traverse
column densities of $\sim 5 \times 10^{27}- 2 \times 10^{28}$ eV/cm$^2$ after
being accelerated in order to reproduce the observed knee, and predicts that
the CR composition should become lighter above $\sim 10^{16}$ eV.

</DOC>
<DOC>
<DOCNO> 116802 </DOCNO>
Coherence-controlled transparency and far-from-degenerate parametric


  An inversionless gain of anti-Stokes radiation above the oscillation
threshold in an optically-dense far-from-degenerate double-Lambda
Doppler-broadened medium accompanied by Stokes gain is predicted. The outcomes
are illustrated with numerical simulations applied to sodium dimer vapor.
Optical switching from absorption to gain via transparency controlled by a
small variation of the medium and of the driving radiation parameters which are
at a level less than one photon per molecule is shown. Related video/audio
clips see in: A.K. Popov, S.A. Myslivets, and T.F. George, Optics Express Vol.
7, No 3, 148 (2000)(http://epubs.osa.org/oearchive/source/22947.htm) or
download: http://kirensky.krasn.ru/popov/opa/opa.htm

</DOC>
<DOC>
<DOCNO> 122846 </DOCNO>
Broad P Cygni X-ray Lines from Circinus X-1


  Chandra High Energy Transmission Grating Spectrometer (HETGS) observations of
the extremely luminous and violent X-ray binary Cir X-1 reveal many X-ray
emission lines showing broad P Cygni profiles. These are from H-like and
He-like ions of Ne, Mg, Si, S, Ar, and Fe. The lines originate in a
high-velocity (up to 2000 km s^-1) outflow, which may be an accretion disk
wind. Cir X-1 has a radio jet, and during some periastron passages of the
neutron star (orbital phase = 0.0), it flares at radio, infrared and X-ray
wavelengths. The X-ray P Cygni profiles were observed during this phase, where
we also expect the strongest mass transfer from the companion star. We present
new results on the time variability of the P Cygni profiles and discuss their
general importance.

</DOC>
<DOC>
<DOCNO> 70620 </DOCNO>
A Measurement of the Average Longitudinal Development Profile of Cosmic


  The average extensive air shower longitudinal development profile as a
function of shower age in the energy range from 10$^{17}$ to 10$^{18}$eV is
measured using data from the hybrid HiRes/MIA experiment. An angular bin signal
based Cerenkov light component subtraction method and a shower maximum fitting
method using a local parabolic function are used to correct and normalize the
data. The Gaisser-Hillas and Greisen functions work equally well for describing
the shower profile. The Gaussian function is a poor fit. A simple scale-free
function is proposed and fits the data equally well. The best-fit parameters
for the above functions are determined.

</DOC>
<DOC>
<DOCNO> 83318 </DOCNO>
To Preference via Entrenchment


  We introduce a simple generalization of Gardenfors and Makinson's epistemic
entrenchment called partial entrenchment. We show that preferential inference
can be generated as the sceptical counterpart of an inference mechanism defined
directly on partial entrenchment.

</DOC>
<DOC>
<DOCNO> 116951 </DOCNO>
High Power Operations of LEDA


  The LEDA RFQ, a 350-MHz continuous wave (CW) radio-frequency quadrupole
(RFQ), successfully accelerated a 100-mA CW proton beam from 75 keV to 6.7 MeV.
We have accumulated 111 hr of beam on time with at least 90 mA of CW output
beam current. The 8-m-long RFQ accelerates a dc, 75-keV, ~106-mA H+ beam from
the LEDA injector with ~94% transmission. When operating the RFQ at the RF
power level for which it was designed, the peak electrical field on the vane
tips is 33 MV/m. However, to maintain the high transmission quoted above with
the CW beam, it was necessary to operate the RFQ with field levels ~10% higher
than design. The RFQ dissipates 1.5 MW of RF power when operating with this
field. Three klystrons provide the 2.2 MW of RF power required by the RFQ to
accelerate the 100-mA beam. The beam power is 670 kW. Some of the challenges
that were met in accelerating a 100-mA CW proton beam to 6.7 MeV, will be
discussed.

</DOC>
<DOC>
<DOCNO> 120602 </DOCNO>
Detection of the old stellar component of the major Galactic bar


  We present near-IR colour--magnitude diagrams and star counts for a number of
regions along the Galactic plane. It is shown that along the l=27 b=0 line of
sight there is a feature at 5.7 +-0.7kpc with a density of stars at least a
factor two and probably more than a factor five times that of the disc at the
same position. This feature forms a distinct clump on an H vs. J-H diagram and
is seen at all longitudes from the bulge to about l=28, but at no longitude
greater than this. The distance to the feature at l=20 is about 0.5kpc further
than at l=27 and by l=10 it has merged with, or has become, the bulge. Given
that at l=27 and l=21 there is also a clustering of very young stars, the only
component that can reasonably explain what is seen is a bar with half length of
around 4kpc and a position angle of about 43+-7.

</DOC>
<DOC>
<DOCNO> 80651 </DOCNO>
One loop renormalisation of Lattice NRQCD currents for semileptonic


  We present the results of a perturbative calculation to match the axial and
vector currents for semileptonic $B\to D^{(\ast)}$ decays in lattice NRQCD to
the continuum \MSb scheme. The matching is performed to
$O(\alpha_s\frac{\vec{p}}{M})$ in Feynman gauge and in the on-shell
renormalisation scheme.
  The spatial and temporal components of the currents renormalise differently;
to this order the matching involves a straightforward renormalisation for the
$V_0$ and $A_k$ currents, and a rank two and four mixing matrix for the $A_0$
and $V_k$ currents respectively. The resultant one loop corrections are of
$O(5%)$, boding well for the accuracy of forthcoming simulations.

</DOC>
<DOC>
<DOCNO> 8722 </DOCNO>
Subtle Features in Transport Properties: Evidence for a Possible


  Transport properties of high transition temperature (high Tc) cuprate
superconductors are investigated within a two-band model. The doping dependent
Hall coefficients of La_{2-x}Sr_xCuO_4 (LSCO) and Nd_{2-x}Ce_xCuO_4 (NCCO) are
explained by assuming the coexistence of two carriers with opposite charges,
loosely speaking electrons (e) and holes (h). Such a possible electron-hole
coexistence (EHC) in other p-type cuprates is also inferred from subtle
features in the Hall coefficient R_H and thermopower S. The EHC possibly
relates to the pseudogap and sign reversals of transport coefficients near Tc.
It also corroborates the electronlike Fermi surface revealed in recent
photoemission results. An experimental verification is proposed.

</DOC>
<DOC>
<DOCNO> 11506 </DOCNO>
Pseudogap and Kinetic Pairing Under Critical Differentiation of


  Superconducting mechanism of cuprates is discussed in the light of the
proximity of the Mott insulator. The proximity accompanied by suppression of
coherence takes place in an inhomogeneous way in the momentum space in
finite-dimensional systems. Studies on instabilities of metals consisted of
such differentiated electrons in the momentum space are reviewed from a general
point of view. A typical example of the differentiation is found in the
flattening of the quasiparticle dispersion discovered around momenta $(\pi,0)$
and $(0,\pi)$ on 2D square lattices. This flattening even controls the
criticality of the metal-insulator transition. Such differentiation and
suppressed coherence subsequently cause an instability to the superconducting
state in the second order of the strong coupling expansion. The d-wave pairing
interaction is generated from such local but kinetic processes in the absence
of disturbance from the coherent single-particle excitations. The
superconducting mechanism emerges from a direct kinetic origin which is
conceptually different from the pairing mechanism mediated by bosonic
excitations as in magnetic, excitonic, and BCS mechanisms. Pseudogap phenomena
widely observed in the underdoped cuprates are then naturally understood from
the mode-mode coupling of d-wave superconducting (dSC) fluctuations repulsively
coupled with antiferromagnetic (AFM) ones. When we assume the existence of a
strong d-wave channel repulsively competing with AFM fluctuations under the
formation of flat and damped single-particle dispersion, we reproduce basic
properties of the pseudogap seen in the magnetic resonance, neutron scattering,
angle resolved photoemission and tunneling measurements in the cuprates.

</DOC>
<DOC>
<DOCNO> 170379 </DOCNO>
Decoherence within a single atom


  An "almost diagonal" reduced density matrix (in coordinate representation) is
usually a result of environment induced decoherence and is considered the sign
of classical behavior. We point out that the proton of a ground state hydrogen
atom can possess such a density matrix. We demonstrate on this example that an
"almost diagonal" reduced density matrix may derive from an interaction with a
low number of degrees of freedom (in our case with a single electron) which
play the role of the environment. We also show that decoherence effects in our
example can only be observed if the interaction with the measuring device is
significantly faster than the interaction with the environment (the electron).
In the opposite case, when the interaction with the environment is significant
during the measurement process, coherence is restored.
 Finally, we propose a neutron scattering experiment on cold He atoms to
observe decoherence which shows up as an additional contribution to the
differential scattering cross section.

</DOC>
<DOC>
<DOCNO> 40125 </DOCNO>
The Atmospheric Neutrino Anomaly: Muon Neutrino Disappearance


  With the 1998 announcement of new evidence for muon neutrino disappearance
observed by the Super-Kamiokande experiment, the more than a decade old
atmospheric neutrino anomaly moved from a possible indication for neutrino
oscillations to an almost inescapable implication. The evidence from all
experiments is reviewed, and indications are presented that the oscillations
are probably between muon and tau neutrinos with nearly maximal mixing.
Implications and future directions in neutrino oscillations research are
discussed.

</DOC>
<DOC>
<DOCNO> 8188 </DOCNO>
Temperature effect in the Casimir attraction of a thin metal film


  The Casimir effect for conductors at arbitrary temperatures is theoretically
studied. By using the analytical properties of the Green functions and applying
the Abel-Plan formula to Lifshitz's equation, the Casimir force is presented as
sum of a temperature dependent and vacuum contributions of the fluctuating
electromagnetic field. The general results are applied to the system consisting
of a bulk conductor and a thin metal film. It is shown that a characteristic
frequency of the thermal fluctuations in this system is proportional to the
square root of a thickness of the metal film. For the case of the sufficiently
high temperatures when the thermal fluctuations play the main role in the
Casimir interaction, this leads to the growth of the effective dielectric
permittivity of the film and to a disappearance of the dependence of Casimir's
force on the sample thickness.

</DOC>
<DOC>
<DOCNO> 11669 </DOCNO>
Ohmic Losses in Valence-band Photoemission Experiments


  Photoemission experiments involve the motion of an electron near a conducting
surface. This necessarily generates heat by ohmic losses from eddy currents.
This inelastic scattering of the electrons will result in a downward shift in
observed spectra. This effect is most pronounced in poorly conducting metals:
in good metals the electron's field is screened out of the material, while
insulators are by definition unable to absorb electromagnetic energy at low
frequencies. We give a classification of photoemission processes which shows
that the effect is an extrinsic proces distinct from final state effects. The
shift is illustrated by a model system with a Drude-like conductivity function
and a temperature-dependent relaxation time. We give a brief experimental
survey of systems in which the ohmic losses may be significant.

</DOC>
<DOC>
<DOCNO> 120054 </DOCNO>
Redshift distribution of {\bf Ly-$\alpha$} lines and metal systems


  The observed redshift distribution of Ly-$\alpha$ lines and metal systems is
examined in order to discriminate and to trace the evolution of structure
elements observed in the galaxy distribution, at small redshifts, and to test
the theoretical description of structure evolution. We show that the expected
evolution of filamentary component of structure describes quite well the
redshift distribution of metal systems and stronger Ly-$\alpha$ lines with
$\log(N_{HI})\geq$14, at $z\leq$ 3. The redshift distribution of weaker
Ly-$\alpha$ lines can be attributed to the population of poorer structure
elements (Zel'dovich pancakes), which were formed at high redshifts from the
invisible DM and non luminous baryonic matter, and at lower redshifts they
mainly merged and dispersed.

</DOC>
<DOC>
<DOCNO> 72092 </DOCNO>
Meson-Baryon Couplings and the F/D ratio in Light Cone QCD


  Using the general form of the baryon currents, we calculate the meson-baryon
coupling constants and the F/D ratio within the framework of light cone QCD sum
rules in the SU(3) flavor symmetry limit. The dependence of the results on the
Dirac structure and on the free parameter b appearing in the general baryon
current is considered. Comparison of our results on F/D ratio with the existing
results is presented.

</DOC>
<DOC>
<DOCNO> 120194 </DOCNO>
The IRAS view of the Local Universe


  We summarise results for the predicted density and peculiar velocity fields
from the PSCz survey. We have used a generalisation of the Path Interchange
Zeldovich Approximation to determine the velocity field; the most remarkable
feature being a coherent large-scale flow along the baseline connecting the
Local Supercluster, Centaurus and the Shapley Concentration. Comparison of the
predicted and observed bulk flows gives a value of beta = 0.50+-0.1.
  We re-examine the PSCz dipole, with improved redshift completeness at
low-latitudes and using PIZA to estimate real-space distances. We find the
dipole to be stable between 80 and 180 hMpc, although there appears to be a
significant contribution to the dipole around 200 hMpc. The overall
misalignment with the CMB dipole remains at 20degrees. The implied value of
beta is in the range 0.40-0.55 with statistical error +-0.1. We also present
the density field and a preliminary dipole analysis from the almost completed
Behind The Plane survey, which extends the PSCz to cover 93% of the sky
including the proposed core of the Great Attractor. We find a density peak at
(325,-5,3500km/s), about half as massive as Centaurus or Pavo-Indus, and
forming part of a continuous filament linking them across the Plane. We also
find evidence for a much larger `Greater Attractor' directly behind the GA, at
a distance of 125 hMpc, and more massive than the Shapley concentration.
  At large distances the dipole direction is in much improved agreement with
the CMB: at 250-300hMpc, the misalignment is only 5-10 degrees, though this
depends on the incompleteness corrections made. The dipole amplitude implies a
value for the parameter beta of 0.44+-0.1.

</DOC>
<DOC>
<DOCNO> 12272 </DOCNO>
Attractive Boson and the Gas-Liquid Condensation


  We calculate a grand partition function of the attractive Bose gas in the
infinite space within some approximations. Using the idea of the Yang-Lee
zeros, it is proved that the gas-liquid condensation occurs before the
conventional condition of the Bose-Einstein condensation is satisfied. Further,
it is pointed out that Bosons with a zero momentum play a role of a trigger to
this gas-liquid condensation. We discuss its implication to the trapped atomic
gas.

</DOC>
<DOC>
<DOCNO> 84114 </DOCNO>
On average properties of inhomogeneous cosmologies


  The present talk summarizes the recently progressed state of a systematic
re-evaluation of cosmological models that respect the presence of
inhomogeneities. Emphasis is given to identifying the basic steps towards an
effective (i.e. spatially averaged) description of structural evolution, also
unfolding the various facets of a `smoothed--out' cosmology. We shall highlight
some results obtained within Newtonian cosmology, discuss expansion laws in
general relativity within a covariant fluid approach, and put forward some
promising directions of future research.

</DOC>
<DOC>
<DOCNO> 67920 </DOCNO>
Testing kappa-Poincare' with neutral kaons


  In recent work on experimental tests of quantum-gravity-motivated
phenomenological models, a significant role has been played by the so-called
``$\kappa$'' deformations of Poincar\'e symmetries. Sensitivity to values of
the relevant deformation length $\lambda$ as small as $5 \cdot 10^{-33}m$ has
been achieved in recent analyses comparing the structure of $\kappa$-Poincar\'e
symmetries with data on the gamma rays we detect from distant astrophysical
sources. We investigate violations of CPT symmetry which may be associated with
$\kappa$-Poincar\'e in the physics of the neutral-kaon system. A simple
estimate indicates that experiments on the neutral kaons may actually be more
$\lambda$-sensitive than corresponding astrophysical experiments, and may
already allow to probe values of $\lambda$ of order the Planck length.

</DOC>
<DOC>
<DOCNO> 83410 </DOCNO>
Fault Detection using Immune-Based Systems and Formal Language


  This paper describes two approaches for fault detection: an immune-based
mechanism and a formal language algorithm. The first one is based on the
feature of immune systems in distinguish any foreign cell from the body own
cell. The formal language approach assumes the system as a linguistic source
capable of generating a certain language, characterised by a grammar. Each
algorithm has particular characteristics, which are analysed in the paper,
namely in what cases they can be used with advantage. To test their
practicality, both approaches were applied on the problem of fault detection in
an induction motor.

</DOC>
<DOC>
<DOCNO> 121377 </DOCNO>
Enhanced Microlensing by Stars Around the Black Hole in the Galactic


  The effect of stars on the lensing properties of the supermassive black hole
in the Galactic Center is similar to the effect of planets on microlensing by a
star. We show that the dense stellar cluster around SgrA* increases by factors
of a few the probability of high-magnification lensing events of a distant
background source by the black hole. Conversely, the gravitational shear of the
black hole changes and enhances the microlensing properties of the individual
stars. The effect is largest when the source image lies near the Einstein
radius of the black hole 1.75"+/-0.20" for a source at infinity). We estimate
that the probability of observing at least one distant background star which is
magnified by a factor >5 in any infrared snapshot of the inner ~ 2" of the
Galactic Center is 1% with a K-band detection threshold of 20 mag. The largest
source of uncertainty in this estimate is the luminosity function of the
background stars. The gravitational shear of the black hole lengthens the
duration of high-magnification events near the Einstein radius up to a few
months, and introduces a large variety of lightcurve shapes that are different
from those of isolated microlenses. Identification of such events by image
subtraction can be used to probe the mass function, density and velocity
distributions of faint stars near the black hole, which are not detectable
otherwise.

</DOC>
<DOC>
<DOCNO> 101827 </DOCNO>
Exact triangles in Seiberg-Witten Floer theory. Part IV: Z-graded


  Some aspects of the construction of SW Floer homology for manifolds with
non-trivial rational homology are analyzed. In particular, the case of
manifolds that are obtained as zero-surgery on a knot in a homology sphere, and
for torsion spinc structures. We discuss relative invariants in the case of
torsion spinc structures.

</DOC>
<DOC>
<DOCNO> 102076 </DOCNO>
A Deformation of Three Dimensional BF Theory


  We consider a deformation of three dimensional BF theory by means of the
antifield BRST formalism. Possible deformations for the action and the gauge
symmetries are analyzed. We find a new class of gauge theories which include
nonabelian BF theory, higher dimensional nonlinear gauge theory and topological
membrane theory.

</DOC>
<DOC>
<DOCNO> 85329 </DOCNO>
Evolution of Differentially Rotating Supermassive Stars to the Onset of


  Thermal emission from a rotating, supermassive star will cause the
configuration to contract slowly and spin up. If internal viscosity and
magnetic fields are sufficiently weak, the contracting star will rotate
differentially. For each of the six initial angular momentum distributions
considered, a cooling supermassive star will likely encounter the dynamical bar
mode instability, which may trigger the growth of nonaxisymmetric bars. This
scenario will lead to the generation of long wavelength gravitational waves,
which could be detectable by future space-based laser interferometers like
LISA.

</DOC>
<DOC>
<DOCNO> 99662 </DOCNO>
Prediction Properties of Aitken's Iterated Delta^2 Process, of Wynn's


  The prediction properties of Aitken's iterated Delta^2 process, Wynn's
epsilon algorithm, and Brezinski's iterated theta algorithm for (formal) power
series are analyzed. As a first step, the defining recursive schemes of these
transformations are suitably rearranged in order to permit the derivation of
accuracy-through-order relationships. On the basis of these relationships, the
rational approximants can be rewritten as a partial sum plus an appropriate
transformation term. A Taylor expansion of such a transformation term, which is
a rational function and which can be computed recursively, produces the
predictions for those coefficients of the (formal) power series which were not
used for the computation of the corresponding rational approximant.

</DOC>
<DOC>
<DOCNO> 116967 </DOCNO>
Beam Energy Stabilization of the Kek 40mev Proton Linac


  The new method to stabilize the beam energy of the KEK 40MeV proton linac, is
developed now. In this method, the signal of the velocity monitor installed
upstream the debuncher in the 40MeV beam line, is processed and then fed to the
phase shifter of the debuncher rf system so as to cancel the fluctuation of the
beam energy. In this article, the beam tests to prove the validity of this
method and the system are described.

</DOC>
<DOC>
<DOCNO> 13083 </DOCNO>
Effects of point defects on the phase diagram of vortex states in


  The phase diagram for the vortex states of high-$T_{\rm c}$ superconductors
with point defects in $\vec{B} \parallel c$ axis is drawn by large-scale Monte
Carlo simulations. The vortex slush (VS) phase is found between the vortex
glass (VG) and vortex liquid (VL) phases. The first-order transition between
this novel normal phase and the VL phase is characterized by a sharp jump of
the density of dislocations. The first-order transition between the Bragg glass
(BG) and VG or VS phases is also clarified. These two transitions are compared
with the melting transition between the BG and VL phases.

</DOC>
<DOC>
<DOCNO> 116710 </DOCNO>
A collision-induced satellite in the Lyman Beta profile due to H-H


  We present a theoretical profile of the Lyman Beta line of atomic hydrogen
perturbed by collisions with neutral hydrogen atoms and protons. We use a
general unified theory in which the electric dipole moment varies during a
collision. A collision-induced satellite appears on Lyman Beta, correlated to
the B''\barB 1Sigma+u - X 1Sigma+g asymptotically forbidden transition of H_2.
As a consequence, the appearance of the line wing between Lyman Alpha and Lyman
Beta is shown to be sensitive to the relative abundance of hydrogen ions and
neutral atoms, and thereby to provide a temperature diagnostic for stellar
atmospheres and laboratory plasmas.

</DOC>
<DOC>
<DOCNO> 71521 </DOCNO>
Leptogenesis in a Realistic Supersymmetric Model of Inflation with a Low


  We discuss leptogenesis in a realistic supersymmetric model of inflation with
a low reheat temperature 1-10 GeV. The lepton asymmetry is generated by a
decaying right handed sneutrino, which is produced after inflation during
preheating. The inflationary model is based on a simple variant of the
Next-to-Minimal Supersymmetric Standard model (NMSSM) which solves the \mu
problem, called \phiNMSSM, where the additional singlet \phi plays the role of
the inflaton in hybrid (or inverted hybrid) type models. The model is invariant
under an approximate Peccei-Quinn symmetry which also solves the strong CP
problem, and leads to an invisible axion with interesting cosmological
consequences. We show how the baryon number of the universe and the nature of
cold dark matter are determined by the same parameters controlling the strong
CP problem, the \mu problem and the neutrino masses and mixing angles.

</DOC>
<DOC>
<DOCNO> 170210 </DOCNO>
Optimal distillation of a GHZ state


  We present the optimal local protocol to distill a
Greenberger-Horne-Zeilinger (GHZ) state from a single copy of any pure state of
three qubits.

</DOC>
<DOC>
<DOCNO> 120751 </DOCNO>
Using galaxy redshift surveys to detect gravitationally-lensed quasars


  Gravitationally-lensed quasars can be discovered as a by-product of galaxy
redshift surveys. Lenses discovered spectroscopically in this way should
require less observational effort per event than those found in dedicated lens
surveys. Further, the lens galaxies should be relatively nearby, facilitating a
number of detailed observations that are impossible for the more common
high-redshift lenses. This is epitomised by the wide range of results that have
been obtained from Q 2237+0305, which was discovered as part of the Center for
Astrophysics redshift survey, and remains the only quasar lens discovered in
this way. The likelihood of this survey yielding a lens is calculated to be
about 0.03, which is an order of magnitude larger than previous estimates due
to two effects. Firstly, the quasar images themselves increase the observed
flux of the lens, so that lens galaxies up to a magnitude fainter than the
nominal survey limit must be included in the calculation. Secondly, it is
possible for lensed quasars with extremely faint deflectors to enter the survey
due to the extended morphology of the multiple images. Extrapolating these
results to future surveys, the 2 degree Field galaxy redshift survey should
contain between 10 and 50 lenses and the Sloan Digital Sky Survey should yield
between 50 and 300 lenses, depending on the cosmological model and the
observing conditions.

</DOC>
<DOC>
<DOCNO> 116889 </DOCNO>
Beam Position-Phase Monitors for SNS Linac


  Electromagnetic modeling with MAFIA of the combined beam position-phase
monitors (BPPMs) for the Spallation Neutron Source (SNS) linac has been
performed. Time-domain 3-D simulations are used to compute the signal
amplitudes and phases on the BPPM electrodes for a given processing frequency,
402.5 MHz or 805 MHz, as functions of the beam transverse position. Working
with a summed signal from all the BPPM electrodes provides a good way to
measure accurately the beam phase. While for an off-axis beam the signal phases
on the individual electrodes can differ from those for a centered beam by a few
degrees, the phase of the summed signal is found to be independent of the beam
transverse position inside the device. Based on the analysis results, an
optimal BPPM design with 4 one-end-shorted 60-degree electrodes has been
chosen. It provides a good linearity and sufficient signal power for both
position and phase measurements, while satisfying the linac geometrical
constrains and mechanical requirements.

</DOC>
<DOC>
<DOCNO> 118633 </DOCNO>
Supermassive Black Holes in Inactive Galaxies


  This article discusses stellar dynamical evidence for supermassive black
holes in inactive and weakly active galaxies.

</DOC>
<DOC>
<DOCNO> 10518 </DOCNO>
Sacrificial Learning in Nonlinear Perceptrons


  Using the cavity method we consider the learning of noisy teacher-generated
examples by a nonlinear student perceptron. For insufficient examples and weak
weight decay, the activation distribution of the training examples exhibits a
gap for the more difficult examples. This illustrates that the outliers are
sacrificed for the overall performance. Simulation shows that the picture of
the smooth energy landscape cannot describe the gapped distributions well,
implying that a rough energy landscape may complicate the learning process.

</DOC>
<DOC>
<DOCNO> 117196 </DOCNO>
The Principle of Synergy and Isomorphic Units


  A solution to the part and whole problem is presented in this paper by using
a complex mathematical representation that permits to define the Holon concept
as a Basic Unit System that remains itself in spite of complex operations such
as integration and derivation. This can be done because of the remarkable
isomorphic property of Euler Relation. We can then define a domain independent
both of the observer and the object, as within it, the object is embedded. We
will then be able to have a Quantum Mechanics solution without the "observer
drawback", as Karl R. Popper tried to find all his life but from the
philosophical point of view and which was Einstein main concern about QM too. A
unit that has always similar or identical structure or form, despite even
complex operations such as integration and derivation, is the ideal unit for
the new sciences of complexity or just the systems sciences too, where
structure or form, wholeness, organization, and complexity are main
requirements. A table for validating the results obtained is presented in case
of the pendulum formula.

</DOC>
<DOC>
<DOCNO> 101973 </DOCNO>
Subgroups of the group of self-homotopy equivalences


  Denote by E(Y) the group of homotopy classes of self-homotopy equivalences of
a finite-dimensional complex Y. We give a selection of results about certain
subgroups of E(Y). We establish a connection between the Gottlieb groups of Y
and the subgroup of E(Y) consisting of homotopy classes of self-homotopy
equivalences that fix homotopy groups through the dimension of Y, denoted by
E_#(Y). We give an upper bound for the solvability class of E_#(Y) in terms of
a cone decomposition of Y. We dualize the latter result to obtain an upper
bound for the solvability class of the subgroup of E(Y) consisting of homotopy
classes of self-homotopy equivalences that fix cohomology groups with various
coefficients. We also show that with integer coefficients, the latter group is
nilpotent.

</DOC>
<DOC>
<DOCNO> 101958 </DOCNO>
Super Star Products and Quantum Superalgebras


  We prove that the super star product on a Poisson Lie supergroup leads to the
structure of quantum superalgebra (triangular Hopf superalgebra) on the super
quantized enveloping algebra of the Lie superalgebra of the Lie supergroup and
that equivalents super star products generate isomorphic quantum superalgebras.

</DOC>
<DOC>
<DOCNO> 121441 </DOCNO>
Eclipse mapping of accretion discs


  The eclipse mapping method is an inversion technique that makes use of the
information contained in eclipse light curves to probe the structure, the
spectrum and the time evolution of accretion discs. In this review I present
the basics of the method and discuss its different implementations. I summarize
the most important results obtained to date and discuss how they have helped to
improve our understanding of accretion physics, from testing the theoretical
radial brightness temperature distribution and measuring mass accretion rates
to showing the evolution of the structure of a dwarf novae disc through its
outburst cycle, from isolating the spectrum of a disc wind to revealing the
geometry of disc spiral shocks. I end with an outline of the future prospects.

</DOC>
<DOC>
<DOCNO> 8396 </DOCNO>
Percolation and Conduction in Restricted Geometries


  The finite-size scaling behaviour for percolation and conduction is studied
in two-dimensional triangular-shaped random resistor networks at the
percolation threshold. The numerical simulations are performed using an
efficient star-triangle algorithm. The percolation exponents, linked to the
critical behaviour at corners, are in good agreement with the conformal
results. The conductivity exponent, t', is found to be independent of the shape
of the system. Its value is very close to recent estimates for the surface and
bulk conductivity exponents.

</DOC>
<DOC>
<DOCNO> 11479 </DOCNO>
The Debye-Waller factor of liquid silica: Theory and simulation


  We show that the prediction of mode-coupling theory for a model of a
network-forming strong glass-former correctly describes the wave-vector
dependence of the Debye-Waller factor. To obtain a good description it is
important to take into account the triplet correlation function c_3, which we
evaluate from a computer simulation. Our results support the possibility that
this theory is able to accurately describe the non-ergodicity parameters of
simple as well as of network-forming liquids.

</DOC>
<DOC>
<DOCNO> 119069 </DOCNO>
Still flat after all these years


  The Universe could be spatially flat, positively curved or negatively curved.
Each option has been popular at various times, partly affected by an
understanding that models tend to evolve away from flatness. The curvature of
the Universe is amenable to measurement, through tests such as the
determination of the angles of sufficiently large triangles. The angle
subtended by the characteristic scale on the Cosmic Microwave sky provides a
direct test, which has now been realised through a combination of exquisite
results from a number of CMB experiments.
  After a long and detailed investigation, with many false clues, it seems that
the mystery of the curvature of the Universe is now solved. It's an open and
shut case: the Universe is flat.

</DOC>
<DOC>
<DOCNO> 152069 </DOCNO>
Remarks on Tachyon Condensation in Superstring Field Theory


  We generalize recent results on tachyon condensation in boundary string field
theory to the superstring.

</DOC>
<DOC>
<DOCNO> 85349 </DOCNO>
Gravitational field and equations of motion of spinning compact binaries


  We derive spin-orbit coupling effects on the gravitational field and
equations of motion of compact binaries in the 2.5 post-Newtonian approximation
to general relativity, one PN order beyond where spin effects first appear. Our
method is based on that of Blanchet, Faye, and Ponsot, who use a post-Newtonian
metric valid for general (continuous) fluids and represent pointlike compact
objects with a delta-function stress-energy tensor, regularizing divergent
terms by taking the Hadamard finite part. To obtain post-Newtonian spin
effects, we use a different delta-function stress-energy tensor introduced by
Bailey and Israel. In a future paper we will use the 2.5PN equations of motion
for spinning bodies to derive the gravitational-wave luminosity and phase
evolution of binary inspirals, which will be useful in constructing matched
filters for signal analysis. The gravitational field derived here may help in
posing initial data for numerical evolutions of binary black hole mergers.

</DOC>
<DOC>
<DOCNO> 117355 </DOCNO>
A Hard Medium Survey with ASCA. III.: a Type 2 AGN revealed from X-ray


  In this paper we report the discovery of an hard X-ray selected Type 2
Seyfert galaxy and we present and discuss its X-ray and optical spectrum
together with the radio to X-ray energy distribution. The X-ray source -
AXJ2254+1146 - is part of the ASCA Hard Serendipitous Survey (HSS). What makes
this discovery particularly noteworthy is the fact that the Type 2
classification of this Seyfert galaxy has resulted directly from the X-ray data
and has been confirmed by optical spectroscopy only subsequently. The X-ray
spectrum of AXJ2254+1146 is best described by a model consisting of an
unresolved Gaussian line at $6.43\pm 0.1$ keV plus the so called
"leaky-absorber" continua having an intrinsic power law photon index of
$\Gamma$ = $2.51^{2.76}_{2.17}$ (1 $\sigma$ confidence interval). The best fit
values of the absorbing column density ($N_H$ = $1.85^{2.24}_{1.47} \times
10^{23}$ cm$^{-2}$), of the line equivalent width ($0.6^{0.84}_{0.36}$ keV) and
of the scattering fraction ($0.7^{1.4}_{0.1} %$), lead us to classify it as a
Type 2 AGN from an X-ray point of view. Inspection of the POSS II image reveals
the presence, within the ASCA X-ray error circle, of the nearby Sbc spiral
galaxy UGC 12237 ($m_{B_o}=14.26$) that, even on positional ground
considerations alone, is the most likely optical counterpart of AXJ2254+1146.
Subsequent optical spectroscopy of UGC 12237 has confirmed its Seyfert 2
optical nature.

</DOC>
<DOC>
<DOCNO> 39791 </DOCNO>
Theoretical Summary Lecture for EPS HEP99


  This is the proceedings article for the concluding lecture of the 1999 High
Energy Physics Conference of the European Physical Society. In this article, I
review a number of topics that were highlighted at the meeting and have more
general importance in high energy physics. The major topics discussed include:
(1) precision electroweak physics, (2) CP violation, (3) new directions in QCD,
(4) supersymmetry spectroscopy, (5) the experimental physics of extra
dimensions.

</DOC>
<DOC>
<DOCNO> 70294 </DOCNO>
Cancellations in Neutrinoless Double Beta Decay and the Neutrino Mass


  In a degenerate scheme with mass m_0 a complete analysis of the allowed range
of the effective electron neutrino Majorana mass <m> is performed. Special
attention is paid to effects of cancellations caused either by intrinsic CP
parities of the eigenstates (CP invariance) or by complex mixing matrix
elements (CP violation). We investigate all possibilities and give in each case
constraints on the phases, the relative CP parities or the neutrino mass scale.
A solar mixing angle \sin^2 2 \theta smaller than 0.7 jeopardizes the
degenerate mass scheme. A key value of <m>/m_0 is identified, which is
independent on the solar solution and would rule out certain schemes. Also it
would answer the question regarding the presence of CP violation. Even if a
total neutrino mass scale and an effective mass is measured, the value of the
phases or parities is not fixed, unless in some special cases. The resulting
uncertainty in the other mass matrix elements is at least of the same order
than the one stemming from nuclear matrix elements calculations.

</DOC>
<DOC>
<DOCNO> 10866 </DOCNO>
Atom loss and the formation of a molecular Bose-Einstein condensate by


  In experiments conducted recently at MIT on Na Bose-Einstein condensates [S.
Inouye et al, Nature 392, 151 (1998); J. Stenger et al, Phys. Rev. Lett. 82,
2422 (1999)], large loss rates were observed when a time-varying magnetic field
was used to tune a molecular Feshbach resonance state near the state of a pair
of atoms in the condensate. A collisional deactivation mechanism affecting a
temporarily formed molecular condensate [see V. A. Yurovsky, A. Ben-Reuven, P.
S. Julienne and C. J. Williams, Phys. Rev. A 60, R765 (1999)], studied here in
more detail, accounts for the results of the slow-sweep experiments. A best fit
to the MIT data yields a rate coefficient for deactivating atom-molecule
collisions of 1.6e-10 cm**3/s. In the case of the fast sweep experiment, a
study is carried out of the combined effect of two competing mechanisms, the
three-atom (atom-molecule) or four-atom (molecule-molecule) collisional
deactivation vs. a process of two-atom trap-state excitation by curve crossing
[F. H. Mies, P. S. Julienne, and E. Tiesinga, Phys. Rev. A 61, 022721 (2000)].
It is shown that both mechanisms contribute to the loss comparably and
nonadditively.

</DOC>
<DOC>
<DOCNO> 39883 </DOCNO>
A new conception experimental test of Bell inequalities using


  We report on a test of Bell inequalities using a non-maximally entangled
state, which represents an important step in the direction of eliminating the
detection loophole. The experiment is based on the creation of a polarisation
entangled state via the superposition, by use of an appropriate optics, of the
spontaneous fluorescence emitted by two non-linear crystals driven by the same
pumping laser. The alignment has profitably taken advantage from the use of an
optical amplifier scheme, where a solid state laser is injected into the
crystals together with the pumping laser. In principle a very high total
quantum efficiency can be reached using this configuration and thus the final
version of this experiment can lead to a resolution of the detection loophole,
we carefully discuss the conditions which must be satisfied for reaching this
result.

</DOC>
<DOC>
<DOCNO> 69684 </DOCNO>
Measuring the SUSY Mass Scale at the LHC


  An effective mass scale Meffsusy for supersymmetric particles is defined and
techniques for its measurement at the LHC discussed. Monte Carlo results show
that, for jets + ETmiss events, a variable constructed from the scalar sum of
the transverse momenta of all reconstructed jets together with ETmiss provides
in most cases the most accurate model independent measurement of Meffsusy
(intrinsic precision ~ 2.1 % for mSUGRA models). The overall precision with
which Meffsusy could be measured after given periods of LHC running and for
given classes of SUSY models is calculated. The technique is extended to
measurements of the total SUSY particle production cross section sigmasusy.

</DOC>
<DOC>
<DOCNO> 68831 </DOCNO>
Vortex configurations in the large N limit


  We study the properties of vortex-like configurations which are solutions of
the SU(N) Yang-Mills classical equations of motion. We show that these
solutions are concentrated along a two-dimensional wall with size growing with
the number of colors.

</DOC>
<DOC>
<DOCNO> 12115 </DOCNO>
Single hole transistor in a p-Si/SiGe quantum well


  A single hole transistor is patterned in a p-Si/SiGe quantum well by applying
voltages to nanostructured top gate electrodes. Gating is achieved by oxidizing
the etched semiconductor surface and the mesa walls before evaporation of the
top gates. Pronounced Coulomb blockade effects are observed at small coupling
of the transistor island to source and drain.

</DOC>
<DOC>
<DOCNO> 119404 </DOCNO>
Correlated V/R and IR photometric variations in the Be/X-ray binary LS I


  We report on the long-term variability of the Be/X-ray binary LS I +61 235/RX
J0146.9+6121. New optical spectroscopic and infrared photometric observations
confirm the presence of global one-arm oscillations in the circumstellar disc
of the Be star and allow us to derive a V/R quasi-period of 1240+-30 days.
Pronounced shell events, reminiscent of the spectacular variations in Be stars,
are also seen. We have found that the J, H and K infrared photometric bands
vary in correlation with the spectroscopic V/R variations, implying that the
one-armed disc oscillations are prograde. The effect of the oscillations is not
only seen in the Halpha line but also in the He I6678 and Paschen lines. Since
these lines are formed at different radii in the equatorial disc of the Be
star, such effect confirms the global nature of the perturbation. The Keplerian
disc has been found to be denser than the average of a sample of isolated Be
stars, which may be indicative of some kind of interaction with the compact
companion. Finally, from a Rossi X-ray Timing Explorer observation we derive a
spin period of the neutron star of 1404.5+-0.5 s.

</DOC>
<DOC>
<DOCNO> 39695 </DOCNO>
Highlights in Neutrino and Astroparticle Physics


  The main highlights from the papers presented at this workshop are briefly
reviewed and discussed in a general context.

</DOC>
<DOC>
<DOCNO> 178470 </DOCNO>
Violation of pseudospin symmetry in nucleon-nucleus scattering: exact


  An exact determination of the size of the pseudospin symmetry violating part
of the nucleon-nucleus scattering amplitude from scattering observables is
presented. The approximation recently used by Ginocchio turns out to
underestimate the violation of pseudospin symmetry. Nevertheless the conclusion
of a modestly broken pseudospin symmetry in proton-208Pb scattering at
EL=800MeV remains valid.

</DOC>
<DOC>
<DOCNO> 12594 </DOCNO>
On the Nature of the Phase Transition Triggered by Vortex-Like Deffects


  The two dimensional lattice Ginzburg-Landau hamiltonian is simulated
numerically for different values of the coherence length $\xi$ in units of the
lattice spacing $a$, a parameter which controls amplitude fluctuations. The
phase diagram on the plane $T-\xi$ is measured. Amplitude fluctuations change
dramatically the nature of the phase transition: for values of $\xi/a \simeq
1$, instead of the smooth Kosterlitz-Thouless transition there is a {\em first
order} transition with a discontinuity in the vortex density $v$ and a sharper
drop in the helicity modulus $\Gamma$. Both observables $v$ and $\Gamma$ are
analyzed in detail at the crossover region between first and second order which
occurs for intermediate values of $\xi/a$.

</DOC>
<DOC>
<DOCNO> 117820 </DOCNO>
Physics of Extremely High Energy Cosmic Rays


  Over the last third of the century, a few tens of events, detected by
ground-based cosmic ray detectors, have opened a new window in the field of
high-energy astrophysics. These events have macroscopic energies, unobserved
sources, an unknown chemical composition and a production and transport
mechanism yet to be explained. With a flux as low as one particle per century
per square kilometer, only dedicated detectors with huge apertures can bring in
the high-quality and statistically significant data needed to answer those
questions. In this article, we review the present status of the field both from
an experimental and theoretical point of view. Special attention is given to
the next generation of detectors devoted to the thorough exploration of the
highest energy ranges

</DOC>
<DOC>
<DOCNO> 71452 </DOCNO>
Chiral Symmetry Restoration and the sigma-meson


  The sigma-meson, which is at best a broad resonance in the vacuum, may suffer
a substantial red-shift and appear as a soft and narrow collective mode at
finite temperature and baryon densities. The physics behind this softening
phenomena and its relation to the partial restoration of chiral symmetry are
discussed. Possible experiments in laboratory to test the idea are also
summarized.

</DOC>
<DOC>
<DOCNO> 123041 </DOCNO>
DarkSUSY - A numerical package for dark matter calculations in the MSSM


  The question of the nature of the dark matter in the Universe remains one of
the most outstanding unsolved problems in basic science. One of the best
motivated particle physics candidates is the lightest supersymmetric particle,
assumed to be the lightest neutralino. We here describe DarkSUSY, an advanced
numerical FORTRAN package for supersymmetric dark matter calculations which we
release for public use. With the help of this package, the masses and
compositions of various supersymmetric particles can be computed, for given
input parameters of the minimal supersymmetric extension of the Standard Model
(MSSM). For the lightest neutralino, the relic density is computed, using
accurate methods which include the effects of resonances, pair production
thresholds and coannihilations. Accelerator bounds are checked to identify
viable dark matter candidates. Finally, detection rates are computed for a
variety of detection methods, such as direct detection and indirect detection
through antiprotons, gamma-rays and positrons from the Galactic halo or
neutrinos from the center of the Earth or the Sun.

</DOC>
<DOC>
<DOCNO> 70125 </DOCNO>
Searching for the Lightest Neutralino at Fixed Target Experiments


  Most ongoing supersymmetry searches have concentrated on the high-energy
frontier. High-intensity fixed target beamlines, however, offer an opportunity
to search for supersymmetric particles with long lifetimes and low
cross-sections in regions complementary to the ones accessible to collider
experiments. In this paper, we consider R-parity violating supersymmetry
searches for the lightest neutralino and use the NuTeV experiment as an example
for the experimental sensitivity which can be achieved.

</DOC>
<DOC>
<DOCNO> 11765 </DOCNO>
Bag Formation in Quantum Hall Ferromagnets


  Charged skyrmions or spin-textures in the quantum Hall ferromagnet at filling
factor nu=1 are reinvestigated using the Hartree-Fock method in the lowest
Landau level approximation. It is shown that the single Slater determinant with
the minimum energy in the unit charge sector is always of the hedgehog form. It
is observed that the magnetization vector's length deviates locally from unity,
i.e. a bag is formed which accommodates the excess charge. In terms of a
gradient expansion for extended spin-textures a novel O(3) type of effective
action is presented, which takes bag formation into account.

</DOC>
<DOC>
<DOCNO> 11503 </DOCNO>
Electron-Phonon Dynamics in an Ensemble of Nearly Isolated Nanoparticles


  We investigate the electron population dynamics in an ensemble of nearly
isolated insulating nanoparticles, each nanoparticle modeled as an electronic
two-level system coupled to a single vibrational mode. We find that at short
times the ensemble-averaged excited-state population oscillates but has a
decaying envelope. At long times, the oscillations become purely sinusoidal
about a ``plateau'' population, with a frequency determined by the
electron-phonon interaction strength, and with an envelope that decays
algebraically as t^-{1/2} We use this theory to predict electron-phonon
dynamics in an ensemble of Y_2 O_3 nanoparticles.

</DOC>
<DOC>
<DOCNO> 99808 </DOCNO>
Das Titsgebaeude von Siegelschen Modulgruppen vom Geschlecht 2


  We calculate Tits buildings for certain arithmetic subgroups of Sp(4). These
give information about the boundary of the corresponding moduli spaces of
abelian surfaces. More pictures (in colour) and a summary of the results (in
English) can be found at http://www.bath.ac.uk/~masgks/Buildings/

</DOC>
<DOC>
<DOCNO> 39991 </DOCNO>
Implications of Improved Upper Bounds on $|\Delta L|=2$ Processes


  We discuss implications of improved upper bounds on the $|\Delta L|=2$
processes (i) $K^+ \to \pi^- \mu^+ \mu^+$, from an experiment at BNL, and (ii)
$\mu^- \to e^+$ conversion, from an experiment at PSI. In particular, we
address the issue of constraints on neutrino masses and mixing, and on
supersymmetric models with R-parity violation.

</DOC>
<DOC>
<DOCNO> 170188 </DOCNO>
Creating macroscopic atomic EPR states from Bose condensates


  We present a scheme for creating quantum entangled atomic states through the
coherent spin-exchange collision of a spinor Bose-Einstein condensate. The
state generated possesses macroscopic Einstein-Podolsky-Roson correlation and
the fluctuation in one of its quasi-spin components vanishes. We show that an
elongated condensate with large aspect ratio is most suitable for creating such
a state.

</DOC>
<DOC>
<DOCNO> 100007 </DOCNO>
A note on asymptotically isometric copies of $l^1$ and $c_0$


  Nonreflexive Banach spaces that are complemented in their bidual by an
L-projection - like preduals of von Neumann algebras or the Hardy space $H^1$ -
contain, roughly speaking, many copies of $l^1$ which are very close to
isometric copies. Such $l^1$-copies are known to fail the fixed point property.
Similar dual results hold for $c_0$.

</DOC>
<DOC>
<DOCNO> 123099 </DOCNO>
Compton scattering sequence reconstruction algorithm for the liquid


  The Liquid Xenon Gamma-Ray Imaging Telescope (LXeGRIT) is a balloon born
experiment sensitive to \g -rays in the energy band of 0.2-20 MeV. The main
detector is a time projection chamber filled with high purity liquid xenon
(LXeTPC), in which the three-dimensional location and energy deposit of
individual \g -ray interactions are accurately measured in one homogeneous
volume. To determine the \g -ray initial direction (Compton imaging), as well
as to reject background, the correct sequence of interactions has to be
determined. Here we report the development and optimization of an algorithm to
reconstruct the Compton scattering sequence and show its performance on Monte
Carlo events and LXeGRIT data.

</DOC>
<DOC>
<DOCNO> 12544 </DOCNO>
"Colliding beam" enhancement mechanism of deuteron-deuteron fusion


  We suggest a ``ping-pong'' mechanism of enhancement for fusion reactions
between a low energy external deuteron beam and the deuterons in a condensed
matter or molecular target. The mechanism is based on the possibility of
acceleration of a target deuteron by the Coulomb field of a projectile deuteron
with its subsequent rebound from a heavy atom in matter and the following
fusion of the two deuterons moving towards each other. This effectively
converts the fixed target process into a colliding beam reaction. In a simple
limiting case this reduces the negative penetrability exponent by a factor of
$\sqrt{2}$. We also discuss a contribution given by ``zero oscillations'' of a
bound target deuteron. The proposed mechanism is expected to be efficient in
compounds with target deuterons localized in the vicinity of heavy atoms.

</DOC>
<DOC>
<DOCNO> 7781 </DOCNO>
Coherent Stranski-Krastanov growth in 1+1 dimensions with anharmonic


  The formation of coherently strained three-dimensional islands on top of the
wetting layer in Stranski-Krastanov mode of growth is considered in a model in
1+1 dimensions accounting for the anharmonicity and non-convexity of the real
interatomic forces. It is shown that coherent 3D islands can be expected to
form in compressed rather than in expanded overlayers beyond a critical lattice
misfit. In the latter case the classical Stranski-Krastanov growth is expected
to occur because the misfit dislocations can become energetically favored at
smaller island sizes. The thermodynamic reason for coherent 3D islanding is the
incomplete wetting owing to the weaker adhesion of the edge atoms. Monolayer
height islands with a critical size appear as necessary precursors of the 3D
islands. The latter explains the experimentally observed narrow size
distribution of the 3D islands. The 2D-3D transformation takes place by
consecutive rearrangements of mono- to bilayer, bi- to trilayer islands, etc.,
after exceeding the corresponding critical sizes. The rearrangements are
initiated by nucleation events each next one requiring to overcome a lower
energetic barrier. The model is in good qualitative agreement with available
experimental observations.

</DOC>
<DOC>
<DOCNO> 12117 </DOCNO>
Elastic response of [111]-tunneling impurities


  We study the dynamic response of a [111] quantum impurity, such as lithium or
cyanide in alkali halides, with respect to an external field coupling to the
elastic quadrupole moment. Because of the particular level structure of a
eight-state system on a cubic site, the elastic response function shows a
biexponential relaxation feature and a van Vleck type contribution with a
resonance frequency that is twice the tunnel frequency $\Delta/\hbar$. This
basically differs from the dielectric response that does not show relaxation.
Moreover, we show that the elastic response of a [111] impurity cannot be
reduced to that of a two-level system. In the experimental part, we report on
recent sound velocity and internal friction measurements on KCl doped with
cyanide at various concentrations. At low doping (45 ppm) we find the dynamics
of a single [111] impurity, whereas at higher concentrations (4700 ppm) the
elastic response rather indicates strongly correlated defects. Our theoretical
model provides a good description of the temperature dependence of $\delta v/v$
and $Q^{-1}$ at low doping, in particular the relaxation peaks, the absolute
values of the amplitude, and the resonant contributions. From our fits we
obtain the value of the elastic deformation potential $\gamma_t=0.192$ eV.

</DOC>
<DOC>
<DOCNO> 100772 </DOCNO>
Some Comments on the RHS Formulation of Resonance Scattering


  We discuss the validity of a formula concerning a relation between
functionals in quantum resonance scattering, which is often used in the current
literature.

</DOC>
<DOC>
<DOCNO> 39902 </DOCNO>
Magnetic monopoles, nuclearites, Q-balls: a qualitative picture


  We present qualitative pictures of the structures of magnetic monopoles
(MMs), nuclearites (nuggets of strange quark matter, strangelets, surrounded by
electrons) and Q-balls (supersymmetric states of squarks, sleptons and Higgs
fields). In particular we discuss the relation between their mass and size.
MMs, nuclearites and Q-balls could be part of the cold Dark Matter (DM); we
consider astrophysical limits on the flux of these particles in the cosmic
radiation.

</DOC>
<DOC>
<DOCNO> 8849 </DOCNO>
Quantum spin hydrodynamics and a new spin-current mode in ferromagnetic


  We derive the quantum spin hydrodynamic equations in a ferromagnetic metal.
  From these equations we show the existence of a new massive spin-current
mode. This mode can be observed in neutron scattering experiments and we
discuss the difficulties in seeing it. At the end we discuss the existence of
this mode in localized ferromagnets.

</DOC>
<DOC>
<DOCNO> 117116 </DOCNO>
Issues and Ramifications in Quantized Fractal Space Time: An Interface


  Recently a stochastic underpinning for space time has been considered, what
may be called Quantized Fractal Space Time. This leads us to a number of very
interesting consequences which are testable, and also provides a rationale for
several otherwise inexplicable features in Particle Physics and Cosmology.
These matters are investigated in the present paper.

</DOC>
<DOC>
<DOCNO> 71902 </DOCNO>
Quark Mass and Flavour Dependence of the QCD Phase Transition


  We analyze the quark mass and flavour dependence of the QCD phase transition
temperature. When the lightest pseudo-scalar meson mass (m_PS) is larger than 2
GeV the critical temperature is controlled by the gluonic sector of QCD alone.
For smaller values of the lightest meson mass the pseudo-critical temperature
decreases slowly with m_PS. For a large regime of meson masses the
pseudo-critical temperature of 2-flavour QCD is about 10% larger than in the
3-flavour case. On lattices with temporal extent N_t=4 an extrapolation to the
chiral limit yields T_c = 173(8) MeV and 154(8) MeV for 2 and 3-flavour QCD,
respectively. We also analyze dynamical quark mass effects on the screening of
the heavy quark potential. A detailed analysis of the heavy quark free energy
in 3-flavour QCD shows that close to T_c screening effects are approximately
quark mass independent already for pseudo-scalar meson masses m_PS = 800 MeV
and screening sets in at distances r = 0.3 fm.

</DOC>
<DOC>
<DOCNO> 122556 </DOCNO>
Gamma Rays from Dark Matter


  I give a brief review of high energy gamma-ray signatures of dark matter. The
decay of massive $X$-particles and subsequent hadronization have been suggested
as the origin of the highest energy cosmic rays. Propagation over cosmological
distances to Earth (as would be the case in some topological defect origin
models for the $X$-particles) results in potentially observable gamma-ray
fluxes at GeV energies. Massive relic particles on the other hand, would
cluster in galaxy halos, including that of our Galaxy, and may give rise to
anisotropic gamma ray and cosmic ray signals at ultra high energies. Future
observations above 100 Gev of gamma rays due to WIMP annihilation in the halo
of the Galaxy may be used to place constraints on supersymmetry parameter
space.

</DOC>
<DOC>
<DOCNO> 170344 </DOCNO>
Tripartite entanglement and quantum relative entropy


  We establish relations between tripartite pure state entanglement and
additivity properties of the bipartite relative entropy of entanglement. Our
results pertain to the asymptotic limit of local manipulations on a large
number of copies of the state. We show that additivity of the relative entropy
would imply that there are at least two inequivalent types of asymptotic
tripartite entanglement. The methods used include the application of some
useful lemmas that enable us to analytically calculate the relative entropy for
some classes of bipartite states.

</DOC>
<DOC>
<DOCNO> 85298 </DOCNO>
Gauge invariance of complex general relativity


  In this paper it is implemented how to make compatible the boundary
conditions and the gauge fixing conditions for complex general relativity
written in terms of Ashtekar variables using the Henneaux-Teitelboim-Vergara
approach. Moreover, it is found that at first order in the gauge parameters,
the Hamiltonian action is (on shell) fully gauge-invariant under the gauge
symmetry generated by the first class constraints in the case when spacetime
$\cal M$ has the topology ${\cal M}= R \times \Sigma$ and $\Sigma$ has no
boundary. Thus, the statement that the constraints linear in the momenta do not
contribute to the boundary terms is right, but only in the case when $\Sigma$
has no boundary.

</DOC>
<DOC>
<DOCNO> 84874 </DOCNO>
A class of colliding waves in metric-affine gravity, nonmetricity and


  By using our recent generalization of the colliding waves concept to
metric-affine gravity theories, and also our generalization of the advanced and
retarded time coordinate representation in terms of Jacobi functions, we find a
general class of colliding wave solutions with fourth degree polynomials in
metric-affine gravity. We show that our general approach contains the standard
second degree polynomials colliding wave solutions as a particular case.

</DOC>
<DOC>
<DOCNO> 170260 </DOCNO>
Quantum Teleportation and Bell's Inequality Using Single-Particle


  A single-particle entangled state can be generated by illuminating a beam
splitter with a single photon. Quantum teleportation utilizing such a
single-particle entangled state can be successfully achieved with a simple
setup consisting only of linear optical devices such as beam splitters and
phase shifters. Application of the locality assumption to a single-particle
entangled state leads to Bell's inequality, a violation of which signifies the
nonlocal nature of a single particle.

</DOC>
<DOC>
<DOCNO> 84472 </DOCNO>
Excision of `repulson' singularities: a spacetime result and its gauge


  We discuss spacetime singularity resolution in the context of the
gravity/gauge correspondence, for brane systems which give rise to gauge
theories with eight supercharges and no hypermultiplets. The discussion is
aimed at non-experts. Writeup of talk on hep-th/9911161 with C.V.Johnson and
J.Polchinski, given in various forms at: PASCOS-99, Aspen winter conference
`Way Beyond the Standard Models', Banff CIAR Gravity+Cosmology Programme
Meeting.

</DOC>
<DOC>
<DOCNO> 101950 </DOCNO>
One Particle (improper) states and Scattering States in Nelson's


  In the one nucleon sector of Nelson's massless model with an ultraviolet
cut-off and no infrared regularization, one particle improper states are
constructed and a scattering theory is developed both for the massless scalar
field and for the non-relativistic particle.

</DOC>
<DOC>
<DOCNO> 8183 </DOCNO>
Multiple-scattering effects on incoherent neutron scattering in glasses


  Incoherent neutron scattering experiments are simulated for simple dynamic
models: a glass (with a smooth distribution of harmonic vibrations) and a
viscous liquid (described by schematic mode-coupling equations). In most
situations multiple scattering has little influence upon spectral
distributions, but it completely distorts the wavenumber-dependent amplitudes.
This explains an anomaly observed in recent experiments.

</DOC>
<DOC>
<DOCNO> 120311 </DOCNO>
Extreme intranight variability in the BL Lacertae object AO 0235+164


  We present results of two-colour photometry with high time resolution of the
violently variable BL Lac object AO 0235+164. We have found extreme intranight
variability with amplitudes of ~ 100 % over time scales of 24 hours. Changes of
0.5 magnitudes in both R and V bands were measured within a single night, and
variations up to 1.2 magnitudes occurred from night to night. A complete
outburst with an amplitude ~ 30 % was observed during one of the nights, while
the spectrum remained unchanged. This seems to support an origin based on a
thin relativistic shock propagating in such a way that it changes the viewing
angle, as recently suggested by Kraus et al. (1999) and Qian et al. (2000).

</DOC>
<DOC>
<DOCNO> 174506 </DOCNO>
Properties of Some Resonances of the 55Mn(p,g)56Fe Reaction in the Ep =


  Radiative decay of 21 resonances in the 55Mn(p,g)56Fe reaction was studied in
the proton beam energy region Ep = 1.3 - 1.8 MeV. Branching of decay to many
low lying bound states up to excitation energy Ex ~ 8 MeV was measured. Exact
energy of all resonances has been established what pointed out that five of the
resonances are very close doublets. For all studied resonances were determined
their spin-parity charakteristics. Assignment of some resonances as isobaric
analogues of the states in the 56Mn nucleus was discused and short note about
energy systematics of isobaric analogue resonances was shown.

</DOC>
<DOC>
<DOCNO> 178798 </DOCNO>
Microscopic model approaches to fragmentation of nuclei and phase


  The properties of excited nuclear matter and the quest for a phase transition
which is expected to exist in this system are the subject of intensive
investigations. High energy nuclear collisions between finite nuclei which lead
to matter fragmentation are used to investigate these properties. The present
report covers effective work done on the subject over the two last decades. The
analysis of experimental data is confronted with two major problems, the
setting up of thermodynamic equilibrium in a time-dependent fragmentation
process and the finite size of nuclei. The present status concerning the first
point is presented. Simple classical models of disordered systems are derived
starting with the generic bond percolation approach. These lattice and cellular
equilibrium models, like percolation approaches, describe successfully
experimental fragment multiplicity distributions. They also show the properties
of systems which undergo a thermodynamic phase transition. Physical observables
which are devised to show the existence and to fix the order of critical
behaviour are presented. Applications to the models are shown. Thermodynamic
properties of finite systems undergoing critical behaviour are advantageously
described in the framework of the microcanonical ensemble. Applications to the
designed models and to experimental data are presented and analysed.
Perspectives of further developments of the field are suggested.

</DOC>
<DOC>
<DOCNO> 118457 </DOCNO>
Redshifts of CLASS Radio Sources


  Spectroscopic observations of a sample of 42 flat-spectrum radio sources from
the Cosmic Lens All-Sky Survey (CLASS) have yielded a mean redshift of $<z> =
1.27$ with an RMS spread of 0.95, at a completeness level of 64%. The sample
consists of sources with a 5-GHz flux density of 25-50 mJy, making it the
faintest flat-spectrum radio sample for which the redshift distribution has
been studied. The spectra, obtained with the Willam Herschel Telescope (WHT),
consist mainly of broad-line quasars at $z>1$ and narrow-line galaxies at
$z<0.5$. Though the mean redshift of flat-spectrum radio sources exhibits
little variation over more than two orders of magnitude in radio flux density,
there is evidence for a decreasing fraction of quasars at weaker flux levels.
In this paper we present the results of our spectroscopic observations, and
discuss the implications for constraining cosmological parameters with
statistical analyses of the CLASS survey.

</DOC>
<DOC>
<DOCNO> 13771 </DOCNO>
Interaction potential between dynamic dipoles: polarized excitons in


  The interaction potential of a two-dimensional system of excitons with
spatially separated electron-hole layers is considered in the strong magnetic
field limit. The excitons are assumed to have free dynamics in the $x$-$y$
plane, while being constrained or `polarized' in the $z$ direction. The model
simulates semiconductor double layer systems under strong magnetic field normal
to the layers. The {\em residual} interaction between excitons exhibits
interesting features, arising from the coupling of the center-of-mass and
internal degrees of freedom of the exciton in the magnetic field. This coupling
induces a dynamical dipole moment proportional to the center-of-mass magnetic
moment of the exciton. We show the explicit dependence of the inter-exciton
potential matrix elements, and discuss the underlying physics. The unusual
features of the interaction potential would be reflected in the collective
response and non-equilibrium properties of such system.

</DOC>
<DOC>
<DOCNO> 68664 </DOCNO>
Neutrino-photon Scattering in a Magnetic Field


  Previous calculations of photon-neutrino scattering in a constant background
magnetic field are extended and corrected.

</DOC>
<DOC>
<DOCNO> 178663 </DOCNO>
A Dirac-Hartree-Bogoliubov approximation for finite nuclei


  We develop a complete Dirac-Hartree-Fock-Bogoliubov approximation to the
ground state wave function and energy of finite nuclei. We apply it to
spin-zero proton-proton and neutron-neutron pairing within the
Dirac-Hartree-Bogoliubov approximation (we neglect the Fock term), using a
zero-range approximation to the relativistic pairing tensor. We study the
effects of the pairing on the properties of the even-even nuclei of the
isotopic chains of Ca, Ni and Sn (spherical) and Kr and Sr (deformed), as well
as the $N$=28 isotonic chain, and compare our results with experimental data
and with other recent calculations.

</DOC>
<DOC>
<DOCNO> 70302 </DOCNO>
Off-forward parton distributions and impact parameter dependent parton


  The connection between parton distributions as a function of the impact
parameter and off-forward parton distributions is discussed in the limit of
vanishing skewedness parameter $\xi$, i.e. when the off-forwardness is purely
transverse. It is also illustrated how to relate $\xi\neq 0$ data to $\xi=0$
data, which is important for experimental measurements of these observables.

</DOC>
<DOC>
<DOCNO> 121551 </DOCNO>
Red Quasars and Quasar Evolution: the Case of BALQSO FIRST


  We present the first near-IR spectroscopy of the z=1.5 radio-loud BALQSO
FIRST J155633.8+351758. Both the Balmer decrement and the slope of the
rest-frame UV-optical continuum independently suggest a modest amount of
extinction along the line of sight to the BLR (E(B-V)~0.5 for SMC-type screen
extinction at the QSO redshift). The implied gas column density along the line
of sight is much less than is implied by the weak X-ray flux of the object,
suggesting that either the BLR and BAL region have a low dust-to-gas ratio, or
that the rest-frame optical light encounters significantly lower mean column
density lines of sight than the X-ray emission. From the rest-frame UV-optical
spectrum, we are able to constrain the stellar mass content of the system.
Comparing the maximal stellar mass with the black hole mass estimated from the
bolometric luminosity of the QSO, we find that the ratio of the black hole to
stellar mass may be comparable to the Magorrian value, which would imply that
the Magorrian relation is already in place at z=1.5. However, multiple factors
favor a much larger black hole to stellar mass ratio. This would imply that if
the Magorrian relation characterizes the late history of QSOs, and the
situation observed for F1556+3517 is typical of the early evolutionary history
of QSOs, central black hole masses develop more rapidly than bulge masses.
[ABRIDGED]

</DOC>
<DOC>
<DOCNO> 122756 </DOCNO>
Galaxy mapping with the SAURON integral-field spectrograph: The star


  We report the first wide-field mapping of the kinematics and stellar
populations in the E3 galaxy NGC 4365. The velocity maps extend previous
long-slit work. They show two independent kinematic subsystems: the central 300
x 700 pc rotates about the projected minor axis, and the main body of the
galaxy, 3 x 4 kpc, rotates almost at right angles to this. The line-strength
maps show that the metallicity of the stellar population decreases from a
central value greater than solar, to one-half solar at a radius of 2 kpc. The
decoupled core and main body of the galaxy have the same luminosity-weighted
age, of ~14 Gyr, and the same elevated magnesium-to-iron ratio. The two
kinematically distinct components have thus shared a common star formation
history. We infer that the galaxy underwent a sequence of mergers associated
with dissipative star formation that ended >12 Gyr ago. The misalignment
between the photometric and kinematic axes of the main body is unambiguous
evidence of triaxiality. The similarity of the stellar populations in the two
components suggests that the observed kinematic structure has not changed
substantially in 12 Gyr.

</DOC>
<DOC>
<DOCNO> 178973 </DOCNO>
Cranked relativistic Hartree-Bogoliubov theory: Superdeformation in the


  A systematic investigation of the yrast superdeformed (SD) rotational bands
in even-even nuclei of the $A\sim 190$ mass region has been performed within
the framework of the cranked relativistic Hartree-Bogoliubov theory. The
particle-hole channel of this theory is treated fully relativistically, while a
finite range two-body force of Gogny type is used in the particle-particle
(pairing) channel. Using the well established parameter sets NL1 for the
Lagrangian and D1S for the Gogny force, very good description of experimental
data is obtained with no adjustable parameters.

</DOC>
<DOC>
<DOCNO> 11385 </DOCNO>
Cuprates: experiment vs. quasiparticle theory


  Comment on the view of P.W. Anderson on the cuprates, as expressed in the
Feb. '00 issue of Physics Today.

</DOC>
<DOC>
<DOCNO> 7778 </DOCNO>
Pair contact process with diffusion - A new type of nonequilibrium


  Recently Carlon et. al. investigated the critical behavior of the pair
contact process with diffusion [cond-mat/9912347]. Using density matrix
renormalization group methods, they estimate the critical exponents, raising
the possibility that the transition might belong to the same universality class
as branching annihilating random walks with even numbers of offspring. This is
surprising since the model does not have an explicit parity-conserving
symmetry. In order to understand this contradiction, we estimate the critical
exponents by Monte Carlo simulations. The results suggest that the transition
might belong to a different universality class that has not been investigated
before.

</DOC>
<DOC>
<DOCNO> 100462 </DOCNO>
2 and 3-dimensional Hamiltonians with Shape Invariance Symmetry


  Via a special dimensional reduction, that is, Fourier transforming over one
of the coordinates of Casimir operator of su(2) Lie algebra and 4-oscillator
Hamiltonian, we have obtained 2 and 3 dimensional Hamiltonian with shape
invariance symmetry. Using this symmetry we have obtained their eigenspectrum.
In the mean time we show equivalence of shape invariance symmetry and Lie
algebraic symmetry of these Hamiltonians.

</DOC>
<DOC>
<DOCNO> 9091 </DOCNO>
The Force-Velocity Relation for Growing Biopolymers


  The process of force generation by the growth of biopolymers is simulated via
a Langevin-dynamics approach. The interaction forces are taken to have simple
forms that favor the growth of straight fibers from solution. The
force-velocity relation is obtained from the simulations for two versions of
the monomer-monomer force field. It is found that the growth rate drops off
more rapidly with applied force than expected from the simplest theories based
on thermal motion of the obstacle. The discrepancies amount to a factor of
three or more when the applied force exceeds 2.5kT/a, where a is the step size
for the polymer growth. These results are explained on the basis of restricted
diffusion of monomers near the fiber tip. It is also found that the mobility of
the obstacle has little effect on the growth rate, over a broad range.

</DOC>
<DOC>
<DOCNO> 174543 </DOCNO>
Longitudinal Momentum Fraction X_L for Two High P_t Protons in pp->ppX


  We present an analysis of new data from Experiment E850 at BNL. We have
characterized the inclusive cross section near the endpoint for pp exclusive
scattering in Hydrogen and in Carbon with incident beam energy of 6 GeV. We
select events with a pair of back-to-back hadrons at large transverse momentum.
These cross sections are parameterized with a form $\frac{d \sigma}{d X_{L}}$
$\sim(1-X_{L})^{p}$, where ${X_{L}}$ is the ratio of the longitudinal momentum
of the observed pair to the total incident beam momentum. Small value of $p$
may suggest that the number of partons participating in the reaction is large
and reaction has a strong dependence on the center-of-mass energy. We also
discuss nuclear effects observed in our kinematic region.

</DOC>
<DOC>
<DOCNO> 116751 </DOCNO>
Physicists Thriving with Paperless Publishing


  The Stanford Linear Accelerator Center (SLAC) and Deutsches Elektronen
Synchrotron (DESY) libraries have been comprehensively cataloguing the High
Energy Particle Physics (HEP) literature online since 1974. The core database,
SPIRES-HEP, now indexes over 400,000 research articles, with almost 50% linked
to fulltext electronic versions (this site now has over 15 000 hits per day).
This database motivated the creation of the first site in the United States for
the World Wide Web at SLAC. With this database and the invention of the Los
Alamos E-print archives in 1991, the HEP community pioneered the trend to
"paperless publishing" and the trend to paperless access; in other words, the
"virtual library." We examine the impact this has had both on the way
scientists research and on paper-based publishing. The standard of work
archived at Los Alamos is very high. 70% of papers are eventually published in
journals and another 20% are in conference proceedings. As a service to
authors, the SPIRES-HEP collaboration has been ensuring that as much
information as possible is included with each bibliographic entry for a paper.
Such meta-data can include tables of the experimental data that researchers can
easily use to perform their own analyses as well as detailed descriptions of
the experiment, citation tracking, and links to full-text documents.

</DOC>
<DOC>
<DOCNO> 116814 </DOCNO>
The interpretations by experimenters of experiments on 'time dilation':


  Experimental tests on `time dilation' began in 1938 with Ives and Stilwell's
work of the transverse Doppler effect due to atoms in inertial flight. Rossi
and Hall (1941) inaugurated the era of fast moving elementary particles that
dominated the scene until the discovery of the Mossbauer effect (1957). This
discovery suggested the use of photons emitted without recoil in crystalline
solids for testing both time dilation and gravitational red shift. Finally,
around 1970, Hafele and Keating dealt again with time dilation by sending
macroscopic atomic clocks around the Earth. The interpretations of these
experiments by experimenters have been characterized by the use of additional
hypotheses not necessary for the formal development of the theories under test
(the idea that all clocks measure proper time) or hypotheses completely
extraneous to the theories themselves (the idea that atoms are clocks). If
these assumptions are dropped, it turns out that the only experiments
concerning time dilation are those performed with elementary particles in
inertial flight. The historical and epistemological implications are discussed.

</DOC>
<DOC>
<DOCNO> 12455 </DOCNO>
Evidence of two viscous relaxation processes in the collective dynamics


  New inelastic X-ray scattering experiments have been performed on liquid
lithium in a wide wavevector range. With respect to the previous measurements,
the instrumental resolution, improved up to 1.5 meV, allows to accurately
investigate the dynamical processes determining the observed shape of the the
dynamic structure factor, $S(Q,\omega)$. A detailed analysis of the lineshapes
shows the co-existence of relaxation processes with both a slow and a fast
characteristic timescales, and therefore that pictures of the relaxation
mechanisms based on a simple viscoelastic model must be abandoned.

</DOC>
<DOC>
<DOCNO> 8316 </DOCNO>
(Noncanonical) field quantization by means of a single harmonic


  The paper is an extension of quant-ph/9912102. The new framework is tested on
the 2-photon spontaneous emission and blackbody radiation. The new effects are
rather subtle. The probability of the 2-photon emission is shown to consist of
a product of several terms: One which is identical to this from standard
quantum optics and the remaining ones formally resembling detector
inefficiencies (here arising from nontrivial vacuum structure). The blackbody
distribution is indistinguishable from the Planck law for T<T_{critical} but
for T>T_{critical} the maximum of the distribution gets lowered and shifts
towards higher frequencies. T_{critical} is a parameter that, in principle,
should be observable. No normal ordering of operators is needed and vacuum
energy is nonzero but finite. Vacuum is represented by a subspace spanned by
ground states of the oscillators and is not equivalent to the cyclic vector of
the GNS construction. The non-CCR algebra is discussed in more detail.

</DOC>
<DOC>
<DOCNO> 123152 </DOCNO>
Associated HI in Absorbers at High Redshift


  WSRT observations have provided a first inventory of the incidence of HI 21
cm line absorption associated with AGN at redshifts up to z=1.0. There is a
large range in line depths, from tau=0.44 to tau less than 0.001, and a
substantial variety of line profiles, from Gaussians of less than ten km/s to
more typically a few hundred km/s, as well as irregular and multi-peaked
absorption, sometimes spanning many hundreds of km/s. The chance to detect
appreciable HI absorption is greatest in the most compact radio sources, GPSs
and CSOs, where it can occur in circumnuclear ``disks'' or ``tori'', as well as
in gas enveloping jets and hot spots; inferred densities range at least between
10 per cubic cm and 10000 per cubic cm. But HI absorption occurs also in some
CSSs, perhaps associated with jet-cloud interaction regions, and in quasars
with a large optical reddening. VLBI observations at the unusual UHF
frequencies of redshifted HI 21 cm can give unique ``sight''lines into the
physics and evolution of young radio sources and their inner galactic medium.

</DOC>
<DOC>
<DOCNO> 99803 </DOCNO>
Promoting finite to infinite symmetries: the 3+1-dimensional analogue of


  Infinite enlargements of finite pseudo-unitary symmetries are explicitly
provided in this letter. The particular case of u(2,2)=so(4,2)+u(1) constitutes
a (Virasoro-like) infinite-dimensional generalization of the 3+1-dimensional
conformal symmetry, in addition to matter fields with all conformal spins.
These algebras provide a new arena for integrable field models in higher
dimensions; for example, Anti-de Sitter and conformal gauge theories of
higher-so(4,2)-spin fields. A proposal for a non-commutative geometrical
interpretation of space is also outlined.

</DOC>
<DOC>
<DOCNO> 100512 </DOCNO>
F-Products and Nonstandard Hulls for Strongly Continuous One-parameter


  We give an overview of the F-product construction and the corresponding
nonstandard constructions for strongly continuous one-parameter semigroups of
linear operators, and show that (in the case of bounded ultrapowers) both
constructs are isomorphic. From this we also deduce a "classical" corollary
about the nonexistace of certain semigroups.

</DOC>
<DOC>
<DOCNO> 39765 </DOCNO>
Large-Area Scintillator Hodoscope with 50 ps Timing Resolution Onboard


  We describe the design and performance of a large-area scintillator hodoscope
onboard the BESS rigidity spectrometer; an instrument with an acceptance of 0.3
m^{2}sr.
  The hodoscope is configured such that 10 and 12 counters are respectively
situated in upper and lower layers.
  Each counter is viewed from its ends by 2.5 inch fine-mesh photomultiplier
tubes placed in a stray magnetic field of 0.2 Tesla.
  Various beam-test data are presented.
  Use of cosmic-ray muons at ground-level confirmed 50 ps timing resolution for
each layer, giving an overall time-of-flight resolution of 70 ps rms using a
pure Gaussian resolution function.
  Comparison with previous measurements on a similar scintillator hodoscope
indicates good agreement with the scaling law that timing resolution is
proportional to 1/$\sqrt{N_{\rm pe}}$, where $N_{\rm pe}$ is the effective
number of photoelectrons.

</DOC>
<DOC>
<DOCNO> 68898 </DOCNO>
Extra Dimension Kaluza-Klein Excitations and Electroweak Symmetry


  We review the possibilities that the Kaluza-Klein excitations of graviton
states induce electroweak symmetry breaking and that electroweak symmetry
breaking could have a large impact on KK phenomenology.

</DOC>
<DOC>
<DOCNO> 9124 </DOCNO>
Generic Criticality in a Model of Evolution


  Using Monte Carlo simulations, we show that for a certain model of biological
evolution, which is driven by non-extremal dynamics, active and absorbing
phases are separated by a critical phase. In this phase both the density of
active sites $\rho(t)$ and the survival probability of spreading $P(t)$ decay
as $t^{-\delta}$, where $\delta \sim 0.5$. At the critical point, which
separates the active and critical phases, $\delta\sim 0.29$, which suggests
that this point belongs to the so-called parity-conserving universality class.
The model has infinitely many absorbing states and, except for a single point,
has no conservation law.

</DOC>
<DOC>
<DOCNO> 117042 </DOCNO>
Comment on "Degenerate Wannier Theory for Multiple Ionization"


  Recent Letter of T.Pattard and J.M.Rost (Phys.Rev.Lett 80, 5081 (1998))
suggests that there exist logarithmic corrections to the near threshold cross
section for the processes of break up of a particle into several charged
fragments. This comment shows that it is incorrect, the logarithmic terms never
exist. The cross section for all processes behaves as some power of the
above-threshold energy, similarly to the known Wannier problem.

</DOC>
<DOC>
<DOCNO> 100757 </DOCNO>
Self-Similar Intermediate Asymptotics for a Degenerate Parabolic


  The equation $$ \partial_tu=u\partial^2_{xx}u-(c-1)(\partial_xu)^2 $$ is
known in literature as a qualitative mathematical model of some biological
phenomena. Here this equation is derived as a model of the groundwater flow in
a water absorbing fissurized porous rock, therefore we refer to this equation
as a filtration-absorption equation. A family of self-similar solutions to this
equation is constructed. Numerical investigation of the evolution of
non-self-similar solutions to the Cauchy problems having compactly supported
initial conditions is performed. Numerical experiments indicate that the
self-similar solutions obtained represent intermediate asymptotics of a wider
class of solutions when the influence of details of the initial conditions
disappears but the solution is still far from the ultimate state: identical
zero. An open problem caused by the nonuniqueness of the solution of the Cauchy
problem is discussed.

</DOC>
<DOC>
<DOCNO> 71527 </DOCNO>
Trace anomalies and the $\Delta I = 1/2$ rule


  Trace Anomaly Dominance in weak $K$-decays successfully reproduces the
$\Delta I = {1\over 2}$ selection rule results, as observed in $K_S \to \pi\pi,
K_L \to \pi\pi\pi, K_S \to \gamma\gamma$ and $K_L \to \pi^0 \gamma\gamma$.

</DOC>
<DOC>
<DOCNO> 70101 </DOCNO>
Three-Body Decays of SUSY Particles


  We analyze the decays of charginos, neutralinos, gluinos and the first/second
generation squarks in the Minimal Supersymmetric extension of the Standard
Model, focusing on the three-body decays in scenarios where the ratio $\tan
\beta$ of vacuum expectation values of the two Higgs doublet fields is large.
We show that the three-body decays of the next-to-lightest neutralinos
(lightest charginos) into $b\bar{b},\tau^+\tau^-$ ($\tau \nu$) final states,
where third generation sfermion and Higgs boson exchange diagrams play an
important role, are dominant. Furthermore, we show that decays of gluinos into
$b\bar{b}$ final states and squark decays into lighter sbottoms through gluino
exchange can also have sizeable branching fractions, especially in scenarios
where the soft SUSY breaking gaugino mass parameters are not unified at the GUT
scale.

</DOC>
<DOC>
<DOCNO> 100314 </DOCNO>
Semi-infinite cohomology and Hecke algebras


  This paper provides a homological algebraic foundation for generalizations of
classical Hecke algebras introduced in math.QA/9805134. These new Hecke
algebras are associated to triples of the form (A,B,e), where A is an
associative algebra containing subalgebra B with character e.
  These algebras are connected with cohomology of associative algebras in the
sense that for every left A-module V and right A-module W the Hecke algebra
associated to triple (A,B,e) naturally acts in the B-cohomology and B-homology
spaces of V and W, respectively.
  We also introduce the semi-infinite cohomology functor for associative
algebras and define modifications of Hecke algebras acting in semi-infinite
cohomology spaces. We call these algebras semi-infinite Hecke algebras.
  As an example we realize the W-algebra W(g) associated to a complex
semisimple Lie algebra g as a semi-infinite Hecke algebra. Using this
realization we explicitly calculate the algebra W(g) avoiding the bosonization
technique used by Feigin and Frenkel.

</DOC>
<DOC>
<DOCNO> 118321 </DOCNO>
Big Bang Nucleosynthesis updated with the NACRE Compilation


  We update the Big Bang Nucleosynthesis calculations on the basis of the
recent NACRE compilation. The average values of the calculated abundances of
light nuclei do not differ significantly from that obtained using the previous
Fowler's compilation.
 ${^7}Li$ is slightly depressed at high baryon to photon ratio $\eta$.
  The main uncertainty concerns the $D(p,\gamma){^3}He$ reaction rate affecting
the synthesis of ${^7}Li$ (via the ${^3}He(\alpha,\gamma){^7}Be(e\nu){^7}Li$)
at rather high baryonic density. On the left part of the lithium valley the
uncertainty is strongly reduced due to the improvement of the measurement of
the $T(\alpha,\gamma)^{7}Li$ reaction rate.
 We use lithium-7 as the main baryometer, since, though much efforts have been
devoted to the determination of Deuterium in absorbing clouds in the line of
sight of remote quasars, the statistics is very poor compared to the long
series of lithium measurements.
 Taking into account the lithium constraints, two possible baryonic density
ranges emerge,
 $\eta_{10}= 1.4 - 1.9$ and $\eta_{10} = 3.3 - 5.1$.
  The Be and B abundances produced in the big bang are orders of magnitudes
lower, and spallation of fast carbon and oxygen is probably their unique
source, in the early Galaxy.

</DOC>
<DOC>
<DOCNO> 152130 </DOCNO>
Fundamental Strings as Noncommutative Solitons


  The interpretation of closed fundamental strings as solitons in open string
field theory is reviewed. Noncommutativity is introduced to facilitate an
explicit construction. The tension is computed exactly and the correct spectrum
is recovered at long wave length.

</DOC>
<DOC>
<DOCNO> 12169 </DOCNO>
Optical properties of quantum wires: Disorder-scattering in the


  The Lloyd model is extended to the exciton problem in quasi one-dimensional
structures to study the interplay between the Coulomb attraction and disorder
scattering. Within this model the averaging and resummation of the locator
series can be performed analytically. As an application, the optical absorption
in quantum box wires is investigated. Without electron-hole interaction,
fluctuations in the well-width lead to an asymmetric broadening of the
minibands with respect to the lower and upper band-edges.

</DOC>
<DOC>
<DOCNO> 8868 </DOCNO>
Effect of short range order on electronic and magnetic properties of


  We here study electronic structure and magnetic properties of disordered CoPd
and CoPt alloys using Augmented Space Recursion technique coupled with the
tight-binding linearized muffin tin orbital (TB-LMTO) method. Effect of short
range ordering present in disordered phase of alloys on electronic and magnetic
properties has been discussed. We present results for magnetic moments, Curie
temperatures and electronic band energies with varying degrees of short range
order for different concentrations of Co and try to understand and compare the
magnetic properties and ordering phenomena in these systems.

</DOC>
<DOC>
<DOCNO> 117118 </DOCNO>
Formation and Primary Heating of The Solar Corona - Theory and


  An integrated Magneto-Fluid model, that accords full treatment to the
Velocity fields associated with the directed plasma motion, is developed to
investigate the dynamics of coronal structures. It is suggested that the
interaction of the fluid and the magnetic aspects of plasma may be a crucial
element in creating so much diversity in the solar atmosphere. It is shown that
the structures which comprise the solar corona can be created by particle
(plasma) flows observed near the Sun's surface - the primary heating of these
structures is caused by the viscous dissipation of the flow kinetic energy.

</DOC>
<DOC>
<DOCNO> 117579 </DOCNO>
The red giant branches of Galactic globular clusters in the [(V-I)o,Mv]


  The purpose of this study is to carry out a thorough investigation of the
changes in morphology of the red giant branch (RGB) of Galactic globular
clusters (GGC) as a function of metallicity, in the V,I bands. To this aim, two
key points are developed in the course of the analysis.
  (a) Using our photometric V,I database for Galactic globular clusters (the
largest homogeneous data sample to date; Rosenberg et al. 1999) we measure a
complete set of metallicity indices, based on the morphology and position of
the red-giant branch. In particular, we provide here the first calibration of
the S, DV_(1.1) and DV_(1.4) indices in the (V-I,V) plane. We show that our
indices are internally consistent, and we calibrate each index in terms of
metallicity, both on the Zinn & West (1984) and the Carretta & Gratton (1997)
scales. Our new calibrations of the (V-I)o,g, DV_(1.2), (V-I)_(-3.0) and
(V-I)_(-3.5) indices are consistent with existing relations.
  (b) Using a grid of selected RGB fiducial points, we define a function in the
{(V-I)o,Mi,[Fe/H]} space which is able to reproduce the whole set of GGC giant
branches in terms of a single parameter (the metallicity). As a first test, we
show that the function is able to predict the correct trend of our observed
indices with metallicity.
  The usage of this function will improve the current determinations of
metallicity and distances within the Local Group, since it allows to easily map
[(V-I)o,Mi] coordinates into {[Fe/H],Mi} ones. To this aim the ``synthetic''
RGB distribution is generated both for the currently used Lee et al. (1990)
distance scale, and for the most recent results on the RR Lyr distance scale.

</DOC>
<DOC>
<DOCNO> 85173 </DOCNO>
Distributional Sources in General Relativity: two point-like examples


  A regularization procedure, that allows one to relate singularities of
curvature to those of the Einstein tensor without some of the shortcomings of
previous approaches, is proposed. This regularization is obtained by requiring
that (i) the density $|det {\bf g}|^{{1/2}}G^a_{b}$, associated to the Einstein
tensor $G^a_{b}$ of the regularized metric, be a distribution with support on a
submanifold of codimension of at most one and (ii) the regularized metric be a
continuous metric which coincides with the singular one everywhere except on
this support. In this paper, the curvature and Einstein tensors of the
geometries associated to point sources in the 2+1-dimensional gravity and the
Schwarzschild spacetime are considered. In both examples the regularized
metrics are shown to be continuous regular metrics, as defined by Geroch and
Traschen, with well defined distributional curvature tensors at all the
intermediate steps of the calculation. The limit in which the support of these
curvature tensors tends to the singular region of the original spacetime is
studied and the results are contrasted with the ones obtained in previous
works.

</DOC>
<DOC>
<DOCNO> 84375 </DOCNO>
Spectral Evolution of the Universe


  We derive the evolution equations for the spectra of the Universe.
  Here "spectra" means the eigenvalues of the Laplacian defined on a space,
which contain the geometrical information on the space.
  These equations are expected to be useful to analyze the evolution of the
geometrical structures of the Universe.
  As an application, we investigate the time evolution of the spectral distance
between two Universes that are very close to each other; it is the first
necessary step for the detailed analysis of the model-fitting problem in
cosmology with the spectral scheme.
  We find out a universal formula for the spectral distance between two very
close Universes, which turns out to be independent of the detailed form of the
distance nor the gravity theory. Then we investigate its time evolution with
the help of the evolution equations we derive.
  We also formulate the criteria for a good cosmological model in terms of the
spectral distance.

</DOC>
<DOC>
<DOCNO> 102424 </DOCNO>
Formal schemes and formal groups


  We set up a framework for using algebraic geometry to study the generalised
cohomology rings that occur in algebraic topology. This idea was probably first
introduced by Quillen and it underlies much of our understanding of complex
oriented cohomology theories, exemplified by the work of Morava. Most of the
results have close and well-known analogues in the algebro-geometric
literature, but with different definitions or technical assumptions that are
often inconvenient for topological applications. We merely put everything
together in a systematic and convenient way.

</DOC>
<DOC>
<DOCNO> 68984 </DOCNO>
New Directions for New Dimensions: From Strings to Neutrinos to Axions


  In this talk, I discuss recent developments concerning the possibility of
large extra spacetime dimensions. After briefly reviewing how such dimensions
can lower the fundamental GUT, Planck, and string scales, I then outline how
these scenarios lead to a new higher-dimensional seesaw mechanism for
generating neutrino oscillations --- perhaps even without neutrino masses. I
also discuss how extra dimensions lead to new mechanisms contributing to the
``invisibility'' of the QCD axion. This talk reports on work done in
collaboration with Emilian Dudas and Tony Gherghetta.

</DOC>
<DOC>
<DOCNO> 85660 </DOCNO>
Positional correlation between low-latitude gamma-ray sources and SNRs


  We present the results of a spatial correlation analysis between unidentified
gamma-ray sources in the 3EG catalog and candidates to supernova remnants. This
work extends a previous study made by Romero, Benaglia & Torres (1999). We also
consider the gamma-ray emission variability and the spectral index for the
sources with positional coincidence.

</DOC>
<DOC>
<DOCNO> 71601 </DOCNO>
The Role of Hadronization in Charm and Beauty Production


  We discuss the relative role of fragmentation and recombination processes for
heavy flavour hadron production in different kinematical regions in high energy
hadron-hadron and photon-hadron collisions. We predict several qualitative
features which should be observed if our picture of heavy flavour production is
consistent.

</DOC>
<DOC>
<DOCNO> 178709 </DOCNO>
Relativistic nuclear structure effects in (e,e' vec{p})


  Results for recoil nucleon induced polarization for $(e,e'\vec{p})$ are
presented using various approximations for the relativistic nucleonic current,
at the kinematics of a recent experiment at Bates. We see that the dynamical
relativistic effects improve the agreement with the data. We make predictions
for the induced normal polarization and responses for TJNAF 89-033 and Mainz
A1/2-93 experiments.

</DOC>
<DOC>
<DOCNO> 71565 </DOCNO>
The $\mu$-Problem and Seesaw-type Mechanism in the Higgs Sector


  We explore a new solution to the $\mu$-problem. In the scenario of
SUSY-breaking mediation through anti-generation fields, we find that the $B\mu$
term has its origin in a seesaw-type mechanism as well as in a loop diagram
through gauge interactions. It is shown that the dominant contributions to the
$B\mu$ term are controlled by the flavor symmetry in the model.

</DOC>
<DOC>
<DOCNO> 10483 </DOCNO>
Spin-transport in multi-terminal normal metal - ferromagnet systems with


  A theory of spin-transport in hybrid normal metal - ferromagnetic electronic
circuits is developed, taking into account non-collinear spin-accumulation.
Spin-transport through resistive elements is described by 4 conductance
parameters. Microscopic expression for these conductances are derived in terms
of scattering matrices and explicitly calculated for simple models. The circuit
theory is applied to 2-terminal and 3-terminal devices attached to
ferromagnetic reservoirs.

</DOC>
<DOC>
<DOCNO> 152353 </DOCNO>
Symplectic leaves of W-algebras from the reduced Kac-Moody point of view


  The symplectic leaves of W-algebras are the intersections of the symplectic
leaves of the Kac-Moody algebras and the hypersurface of the second class
constraints, which define the W-algebra. This viewpoint enables us to classify
the symplectic leaves and also to give a representative for each of them. The
case of the (W_{2}) (Virasoro) algebra is investigated in detail, where the
positivity of the energy functional is also analyzed.

</DOC>
<DOC>
<DOCNO> 84824 </DOCNO>
Cosmological Constant and the Speed of Light


  By exploring the relationship between the propagation of electromagnetic
waves in a gravitational field and the light propagation in a refractive
medium, it is shown that, in the presence of a positive cosmological constant,
the velocity of light will be smaller than its special relativity value. Then,
restricting again to the domain of validity of geometrical optics, the same
result is obtained in the context of wave optics. It is argued that this
phenomenon and the anisotropy in the velocity of light in a gravitational field
are produced by the same mechanism.

</DOC>
<DOC>
<DOCNO> 118254 </DOCNO>
What do $\gamma$-ray bursts look like?


  There have been great and rapid progresses in the field of $\gamma$-ray
bursts (denoted as GRBs) since BeppoSAX and other telescopes discovered their
afterglows in 1997. Here, we will first give a brief review on the
observational facts of GRBs and direct understanding from these facts, which
lead to the standard fireball model. The dynamical evolution of the fireball is
discussed, especially a generic model is proposed to describe the whole
dynamical evolution of GRB remnant from highly radiative to adiabatic, and from
ultra-relativistic to non-relativistic phase. Then, Various deviations from the
standard model are discussed to give new information about GRBs and their
environment. In order to relax the energy crisis, the beaming effects and their
possible observational evidences are also discussed in GRB's radiations.

</DOC>
<DOC>
<DOCNO> 14078 </DOCNO>
First-Order Transition and Critical End-Point in Vortex Liquids in


  We calculate various thermodynamic quantities of vortex liquids in a layered
superconductor by using the nonperturbative parquet approximation method, which
was previously used to study the effect of thermal fluctuations in
two-dimensional vortex systems. We find there is a first-order transition
between two vortex liquid phases which differ in the magnitude of their
correlation lengths. As the coupling between the layers increases,the
first-order transition line ends at a critical point. We discuss the possible
relation between this critical end-point and the disappearance of the
first-order transition which is observed in experiments on high temperature
superconductors at low magnetic fields.

</DOC>
<DOC>
<DOCNO> 151519 </DOCNO>
Elongation of Moving Noncommutative Solitons


  We discuss the characteristic properties of noncommutative solitons moving
with constant velocity. As noncommutativity breaks the Lorentz symmetry, the
shape of moving solitons is affected not just by the Lorentz contraction along
the velocity direction, but also sometimes by additional `elongation'
transverse to the velocity direction. We explore this in two examples:
noncommutative solitons in a scalar field theory on two spatial dimension and
`long stick' shaped noncommutative U(2) magnetic monopoles. However the
elongation factors of these two cases are different, and so not universal.

</DOC>
<DOC>
<DOCNO> 121389 </DOCNO>
On the detection of neutrino oscillations with Planck surveyor


  The imprint of neutrino oscillations on the Cosmic Microwave Background (CMB)
anisotropy and polarization power spectra is evaluated in a $\Lambda$CHDM model
with two active neutrino flavors, consistent with the structure formation
models and the atmospheric neutrino oscillations data. We show the existence of
a significant overlap between the region of the oscillation parameter space
that can be measured by sc Planck surveyor and that implied by the atmospheric
neutrino oscillations data.

</DOC>
<DOC>
<DOCNO> 116773 </DOCNO>
Ultracold Metastable Calcium Ensembles, a Medium for Matter Wave


  We propose an experimental implementation of matter wave amplification by
optical pumping (MAO) with metastable calcium atoms. First experimental results
indicate that pumping rates can be significantly higher than in previous
experimental schemes and let it appear promising that the threshold condition
for generation of degeneracy can be reached.

</DOC>
<DOC>
<DOCNO> 9586 </DOCNO>
Thermodynamics of Gaussian fluctuations and paraconductivity in layered


  A detailed theoretical analysis of the Gaussian fluctuations of the order
parameter in layered superconductors is performed within the Ginzburg-Landau
(GL) theory. The available results for the Gaussian fluctuations are
systematized and a number of novel formulae for the fluctuation magnetization,
nonlinear magnetic susceptibility, heat capacity and high-frequency
conductivity in layered superconductors are derived. We propose several new
prescriptions: how to determine the life-time constant of fluctuation Cooper
pairs tau_0, the in-plane coherence length xi_ab(0), the energy cutoff
parameter e_cut=c hbar^2 / 2m_ab xi^2_ab(0), and the Ginzburg number e_Gi. It
is demonstrated, for example, how the spectroscopy of the life-time can be used
to verify the existence of depairing mechanisms in layered cuprates. The
ultraviolet regularization of the GL free energy is carried out by means of the
well-known from the field theory zeta-function method. We further show that the
archetype of the latter method has its origin in the century of enlightenment
and the novel result is that the fluctuation part of the thermodynamic
variables of the layered superconductors can be expressed in terms of the Euler
Gamma-function and its derivatives. Universal scaling curves for the magnetic
field dependence of the paraconductivity sigma_ab(T_c,B), fluctuation
magnetization M(T_c,B) and the heat capacity C(T_c,B) are found for the
quasi-2D superconductors at T_c and further related to the form-factor of the
Cooper pairs.

</DOC>
<DOC>
<DOCNO> 119982 </DOCNO>
Photospheric Metals in the FUSE Spectrum of the Subdwarf B Star


  We present an abundance analysis of the far-ultraviolet (905--1187 A)
spectrum of the subdwarf B star PG0749+658, obtained by the Far Ultraviolet
Spectroscopic Explorer (FUSE). The data have a resolution of about R = lambda /
Delta lambda = 12000--15000 (20--25 km/s). We determine C, N, Si, P, S, Cr, Mn,
Fe, Co, and Ni abundances, and upper limits on the abundance of Cl and V, using
a grid of synthetic spectra based on a LTE stellar atmosphere model. He, C, N,
Si, and Cl are depleted by a factor of >~10 with respect to solar, while P, S,
and Fe are diminished by less than a factor of 10. We measure a solar abundance
of Cr, Mn, and Co and a Ni enhancement of ~0.6 dex. We compare these values to
predictions based on radiative levitation theory. The radial velocity of the
foreground interstellar material has one dominant component, and coincides with
that of the photospheric lines.

</DOC>
<DOC>
<DOCNO> 70014 </DOCNO>
Three-loop Three-Linear Vertices and Four-Loop MOM beta functions in


  In this paper we present a full set of 2- and 3-point functions for massless
QCD at three-loop order in the MSbar scheme. The vertex functions are evaluated
at the asymmetric point with one vanishing momentum. These results are used to
relate the MSbar coupling constant to that of various momentum subtraction
renormalization schemes at three-loop order. With the help of the known
four-loop MS-bar beta-function we then determine the four-loop coefficients of
the corresponding MOM beta-functions.
  As an application we consider the momentum dependence (running) of the
three-gluon asymmetrical vertex recently computed within the lattice approach
by Ph. Boucaud et al. (JHEP 04 006 (2000)). An account of the four-loop term in
the corresponding beta-function leads to a significant (around 30%) decrease of
the value of the non-perturbative power-suppressed correction to the running.

</DOC>
<DOC>
<DOCNO> 150553 </DOCNO>
Modular Invariance in Superstring on Calabi-Yau n-fold with A-D-E


  We study the type II superstring theory on the background $\br^{d-1,1}\times
X_n$, where $X_n$ is a Calabi-Yau $n$-fold ($2n+d=10$) with an isolated
singularity, by making use of the holographically dual description proposed by
Giveon-Kutasov-Pelc (hep-th/9907178). We compute the toroidal partition
functions for each of the cases $d=6,4,2$, and obtain manifestly modular
invariant solutions classified by the standard $A-D-E$ series corresponding to
the type of singularities on $X_n$. Partition functions of these modular
invariants all vanish due to theta function identities and are consistent with
the presence of space-time supersymmetry.

</DOC>
<DOC>
<DOCNO> 118775 </DOCNO>
A microlensing search for cold molecular clouds in Virgo


  We report preliminary results from a first season of photometric monitoring
of 600 quasars behind the Virgo galaxy cluster with the aim of detecting
microlensing by the cluster dark matter. Our project is sensitive to dark
objects of surface mass densities down to ~20 g/cm^2. We are thus capable of
detecting diffuse objects, such as cold molecular clouds, unlike all Galactic
microlensing surveys whose surface mass density limits are > 10^4 g/cm^2. The
average optical depth to microlensing of quasars through the central 30 sq.
deg. of Virgo is ~1x10^-3. We report a null detection which implies that less
than half the dark matter in Virgo is in objects of mass ~10^-5 solar masses,
of surface mass density > 20 g/cm^2, at 90% confidence.

</DOC>
<DOC>
<DOCNO> 99802 </DOCNO>
Complementary Algorithms For Tableaux


  We study four operations defined on pairs of tableaux. Algorithms for the
first three involve the familiar procedures of jeu de taquin, row insertion,
and column insertion. The fourth operation, hopscotch, is new, although
specialised versions have appeared previously. Like the other three operations,
this new operation may be computed with a set of local rules in a growth
diagram, and it preserves Knuth equivalence class. Each of these four
operations gives rise to an a priori distinct theory of dual equivalence. We
show that these four theories coincide. The four operations are linked via the
involutive tableau operations of complementation and conjugation.

</DOC>
<DOC>
<DOCNO> 152157 </DOCNO>
Vertex Operators for AdS3 with Ramond Background


  This review gives results on vertex operators for the Type IIB superstring in
an AdS3 x S3 background with Ramond-Ramond flux, which were presented at
Strings 2000. Constraint equations for these vertex operators are derived, and
their components are shown to satisfy the supergravity linearized equations of
motion for the six-dimensional (2,0) theory of a supergravity and tensor
multiplet expanded around AdS3 x S3 spacetime.

</DOC>
<DOC>
<DOCNO> 72209 </DOCNO>
Production Processes as a Tool to Study Parameterizations of Quark


  We introduce diquarks as separable correlations in the two-quark Green's
function to facilitate the description of baryons as relativistic three-quark
bound states. These states then emerge as solutions of Bethe-Salpeter equations
for quarks and diquarks that interact via quark exchange. When solving these
equations we consider various dressing functions for the free quark and diquark
propagators that prohibit the existence of corresponding asymptotic states and
thus effectively parameterize confinement. We study the implications of
qualitatively different dressing functions on the model predictions for the
masses of the octet baryons as well as the electromagnetic and strong form
factors of the nucleon. For different dressing functions we in particular
compare the predictions for kaon photoproduction, $\gamma p\to K\Lambda$, and
associated strangeness production, $pp\to pK\Lambda$ with experimental data.
This leads to conclusions on the permissibility of different dressing
functions.

</DOC>
<DOC>
<DOCNO> 10161 </DOCNO>
Edge Critical Behaviour of the 2-Dimensional Tri-critical Ising Model


  Using previous results from boundary conformal field theory and
integrability, a phase diagram is derived for the 2 dimensional Ising model at
its bulk tri-critical point as a function of boundary magnetic field and
boundary spin-coupling constant. A boundary tri-critical point separates phases
where the spins on the boundary are ordered or disordered. In the latter range
of coupling constant, there is a non-zero critical field where the
magnetization is singular. In the former range, as the temperature is lowered,
the boundary undergoes a first order transition while the bulk simultaneously
undergoes a second order transition.

</DOC>
<DOC>
<DOCNO> 152123 </DOCNO>
Nonlinear Supersymmetry Without the GSO Projection and Unstable D9-Brane


  Orientable open string theories containing both bosons and fermions without
the GSO projection are expected to have the 10 dimensional N=2(A) space-time
supersymmetry in a spontaneously broken phase. We study the low-energy theorem
for the nonlinearly realized N=2 supersymmetry using the effective action for
an unstable D9-brane. It is explicitly confirmed that the 4-fermion open string
amplitudes without the GSO projection obey the low-energy theorem derived from
the nonlinear N=2 supersymmetry. An intimate connection between the existence
of the hidden supersymmetry and the open-open string (s-t) duality is pointed
out.

</DOC>
<DOC>
<DOCNO> 119110 </DOCNO>
Mirror Dark Matter


  There appear to be three challenges that any theory of dark matter must face:
(i) why is $\Omega_{DM}$ of the same order as $\Omega_{Baryons}$ ? (ii) what
are the near solar mass objects ($\sim 0.5 M_{\odot}$) observed by the MACHO
microlensing project ? and (iii) understanding the shallow core density profile
of the halos of dwarf as well as low surface brightness galaxies. The popular
cold dark matter candidates, the SUSY LSP and the axion fail to meet these
challenges. We argue that in the mirror model suggested recently to explain the
neutrino anomalies, the mirror baryons being 15-20 times heavier than familiar
baryons, can play the role of the cold dark matter and provide reasonable
explanation of all three above properties without extra assumptions.

</DOC>
<DOC>
<DOCNO> 152543 </DOCNO>
D1/D5 systems in ${\cal N}=4$ string theories


  We propose CFT descriptions of the D1/D5 system in a class of freely acting
Z_2 orbifolds/orientifolds of type IIB theory, with sixteen unbroken
supercharges. The CFTs describing D1/D5 systems involve N=(4,4) or N=(4,0)
sigma models on $(R^3\times S^1\times T^4\times (T^4)^N/S_N)/Z_2$, where the
action of Z_2 is diagonal and its precise nature depends on the model. We also
discuss D1(D5)-brane states carrying non-trivial Kaluza-Klein charges. The
resulting multiplicities for two-charge bound states are shown to agree with
the predictions of U-duality. We raise a puzzle concerning the multiplicities
of three-charge systems, which is generically present in all vacuum
configurations with sixteen unbroken supercharges studied so far, including the
more familiar type IIB on K3 case: the constraints put on BPS counting formulae
by U-duality are apparently in contradiction with any CFT interpretation. We
argue that the presence of RR backgrounds appearing in the symmetric product
CFT may provide a resolution of this puzzle.

</DOC>
<DOC>
<DOCNO> 102705 </DOCNO>
Compact homogeneous CR manifolds


  We classify all compact simply connected homogeneous CR manifolds $M$ of
codimension one and with non-degenerate Levi form up to CR equivalence. The
classification is based on our previous results and on a description of the
maximal connected compact group $G(M)$ of automorphisms of $M$. We characterize
also the standard homogeneous CR manifolds as the homogeneous CR manifolds
whose group $G(M)$ in not semisimple.

</DOC>
<DOC>
<DOCNO> 100692 </DOCNO>
Anti-self-dual Yang-Mills equations on noncommutative spacetime


  By replacing the ordinary product with the so called $\star$-product, one can
construct an analogue of the anti-self-dual Yang-Mills (ASDYM) equations on the
noncommutative $\bbR^4$. Many properties of the ordinary ASDYM equations turn
out to be inherited by the $\star$-product ASDYM equation. In particular, the
twistorial interpretation of the ordinary ASDYM equations can be extended to
the noncommutative $\bbR^4$, from which one can also derive the fundamental
strutures for integrability such as a zero-curvature representation, an
associated linear system, the Riemann-Hilbert problem, etc. These properties
are further preserved under dimensional reduction to the principal chiral field
model and Hitchin's Higgs pair equations. However, some structures relying on
finite dimensional linear algebra break down in the $\star$-product analogues.

</DOC>
<DOC>
<DOCNO> 170339 </DOCNO>
Wave Packet Echoes in the Motion of Trapped Atoms


  We experimentally demonstrate and systematically study the stimulated revival
(echo) of motional wave packet oscillations. For this purpose, we prepare wave
packets in an optical lattice by non-adiabatically shifting the potential and
stimulate their reoccurence by a second shift after a variable time delay. This
technique, analogous to spin echoes, enables one even in the presence of strong
dephasing to determine the coherence time of the wave packets. We find that for
strongly bound atoms it is comparable to the cooling time and much longer than
the inverse of the photon scattering rate.

</DOC>
<DOC>
<DOCNO> 84678 </DOCNO>
Spacetime Measurements in Kaluza-Klein Gravity


  We extend the classical general relativistic theory of measurement to include
the possibility of existence of higher dimensions. The intrusion of these
dimensions in the spacetime interval implies that the inertial mass of a
particle in general varies along its worldline if the observations are analyzed
assuming the existence of only the four spacetime dimensions. The variations of
mass and spin are explored in a simple 5D Kaluza-Klein model.

</DOC>
<DOC>
<DOCNO> 13796 </DOCNO>
Non-Boltzmann Equilibrium Probability Densities for Non-Linear L\'{e}vy


  We study, both analytically and by numerical modeling the equilibrium
probability density function for an non-linear L\'{e}vy oscillator with the
L\'{e}vy index \alpha, 1 \leq \alpha \leq 2, and the potential energy x^4. In
particular, we show that the equilibrium PDF is bimodal and has power law
asymptotics with the exponent -(\alpha +3).

</DOC>
<DOC>
<DOCNO> 84504 </DOCNO>
Relativistic Diskoseismology. II. Analytical Results for C-modes


  We first briefly review how we investigate the modes of oscillation trapped
within the inner region of accretion disks by the strong-field gravitational
properties of a black hole (or a compact, weakly-magnetized neutron star). Then
we focus on the `corrugation'(c)-modes, nearly incompressible perturbations of
the inner disk. The fundamental c-modes have eigenfrequencies (ordered by
radial mode number) which correspond to the Lense-Thirring frequency,
evaluated at the outer trapping radius of the mode, in the slow rotation limit.
This trapping radius is a decreasing function of the black hole angular
momentum, so a significant portion of the disk is modulated only for slowly
rotating black holes. The eigenfrequencies are thus strongly increasing
functions of black hole angular momentum. The dependence of the
eigenfrequencies on the speed of sound within (or the luminosity) within the
disk is very weak, except for slowly rotating black holes.

</DOC>
<DOC>
<DOCNO> 102808 </DOCNO>
Spectra of non-commutative dynamical systems and graphs related to


  We study spectra of noncommutative dynamical systems, representations of
fractal groups, and regular graphs. We explicitly compute these spectra for
five examples of groups acting on rooted trees, and in three cases obtain
totally disconnected sets.

</DOC>
<DOC>
<DOCNO> 9202 </DOCNO>
Direct observation of twist mode in electroconvection in I52


  I report on the direct observation of a uniform twist mode of the director
field in electroconvection in I52. Recent theoretical work suggests that such a
uniform twist mode of the director field is responsible for a number of
secondary bifurcations in both electroconvection and thermal convection in
nematics. I show here evidence that the proposed mechanisms are consistent with
being the source of the previously reported SO2 state of electroconvection in
I52. The same mechanisms also contribute to a tertiary Hopf bifurcation that I
observe in electroconvection in I52. There are quantitative differences between
the experiment and calculations that only include the twist mode. These
differences suggest that a complete description must include effects described
by the weak-electrolyte model of electroconvection.

</DOC>
<DOC>
<DOCNO> 8127 </DOCNO>
Quenched Averaged Correlation Functions of the Random Magnets


  It is shown that the ratios of the quenched averaged three and four-point
correlation functions of the local energy density operator to the connected
ones in the random-bond Ising model approach asymptotically to some $universal$
functions. We derive the explicit expressions of these universal functions.
Moreover it is shown that the individual logarithmic operators have not any
contribution to the connected correlation functions of the disordered Ising
model.

</DOC>
<DOC>
<DOCNO> 119555 </DOCNO>
Resolving the Controversy Over the Core Radius of 47 Tucanae (NGC 104)


  This paper investigates the discrepancy between recent measurements of the
density profile of the globular cluster 47 Tuc that have used HST data sets.
Guhathakurta et al. (1992) used pre-refurbishment WFPC1 V-band images to derive
r_c = 23" +/- 2". Calzetti et al. (1993) suggested that the density profile is
a superposition of two King profiles (r_c = 8" and r_c = 25") based on U-band
FOC images. De Marchi et al. (1996) used deep WFPC1 U-band images to derive r_c
= 12" +/- 2". Differences in the adopted cluster centers are not the cause of
the discrepancy. Our independent analysis of the data used by De Marchi et al.
reaches the following conclusions: (1) De Marchi et al.'s r_c ~ 12" value is
spuriously low, a result of radially-varying bias in the star counts in a
magnitude limited sample -- photometric errors and a steeply rising stellar
luminosity function cause more stars to scatter across the limiting magnitude
into the sample than out of it, especially near the cluster center where
crowding effects are most severe. (2) Changing the limiting magnitude to the
main sequence turnoff, away from the steep part of the luminosity function,
partially alleviates the problem and results in r_c = 18". (3) Combining such a
limiting magnitude with accurate photometry derived from PSF fitting, instead
of the less accurate aperture photometry employed by De Marchi et al., results
in a reliable measurement of the density profile which is well fit by r_c = 22"
+/- 2". Archival WFPC2 data are used to derive a star list with a higher degree
of completeness, greater photometric accuracy, and wider areal coverage than
the WFPC1 and FOC data sets; the WFPC2-based density profile supports the above
conclusions, yielding r_c = 24" +/- 1.9".

</DOC>
<DOC>
<DOCNO> 7868 </DOCNO>
Colour valued Scattering Matrices


  We describe a general construction principle which allows to add colour
values to a coupling constant dependent scattering matrix. As a concrete
realization of this mechanism we provide a new type of S-matrix which
generalizes the one of affine Toda field theory, being related to a pair of Lie
algebras. A characteristic feature of this S-matrix is that in general it
violates parity invariance. For particular choices of the two Lie algebras
involved this scattering matrix coincides with the one related to the scaling
models described by the minimal affine Toda S-matrices and for other choices
with the one of the Homogeneous sine-Gordon models with vanishing resonance
parameters. We carry out the thermodynamic Bethe ansatz and identify the
corresponding ultraviolet effective central charges.

</DOC>
<DOC>
<DOCNO> 152268 </DOCNO>
Single State Supermultiplet in 1+1 Dimensions


  We consider multiplet shortening for BPS solitons in N=1 two-dimensional
models. Examples of the single-state multiplets were established previously in
N=1 Landau-Ginzburg models. The shortening comes at a price of loosing the
fermion parity $(-1)^F$ due to boundary effects. This implies the disappearance
of the boson-fermion classification resulting in abnormal statistics. We
discuss an appropriate index that counts such short multiplets.
  A broad class of hybrid models which extend the Landau-Ginzburg models to
include a nonflat metric on the target space is considered. Our index turns out
to be related to the index of the Dirac operator on the soliton reduced moduli
space (the moduli space is reduced by factoring out the translational modulus).
The index vanishes in most cases implying the absence of shortening. In
particular, it vanishes when there are only two critical points on the compact
target space and the reduced moduli space has nonvanishing dimension.
  We also generalize the anomaly in the central charge to take into account the
target space metric.

</DOC>
<DOC>
<DOCNO> 100544 </DOCNO>
Encomplexing the writhe


  A detailed version of preprint "Self-linking number of a real algebraic link"
by the same author, alg-geom/9410030. For a nonsingular real algebraic curve in
3-dimensional projective space or 3-sphere, a new integer-valued characteristic
is introduced. It is invariant under rigid isotopy and multiplied by -1 under
mirror reflections. In a sense, it is a Vassiliev invariant of degree 1 and a
counterpart of a link diagram writhe. For a regular complete intersection this
invariant vanishes, while for rational knots of degree d it takes all the
values between -(d-1)(d-2)/2 and (d-1)(d-2)/2.

</DOC>
<DOC>
<DOCNO> 120885 </DOCNO>
A New Underground Laboratory in the USA for a Neutrino Factory Detector


  A neutrino factory storage ring can provide beams to various locations. We
discuss the ICANOE detector (at LNGS) at one such site. We then describe the
prospects for the use of the underground location at Carlsbad, NM for a
neutrino factory detector. A brief discussion is given of a simple magnetized
Fe detector of 10 50 kT for this site.

</DOC>
<DOC>
<DOCNO> 9050 </DOCNO>
Justification of Power-Law Canonical Distributions Based on Generalized


  A self-consistent thermodynamic framework is presented for power-law
canonical distributions based on the generalized central limit theorem by
extending the discussion given by Khinchin for deriving Gibbsian canonical
ensemble theory. The thermodynamic Legendre transform structure is invoked in
establishing its connection to nonextensive statistical mechanics.

</DOC>
<DOC>
<DOCNO> 80868 </DOCNO>
Chiral symmetry in lattice QCD


  A chiral invariant effective action for lattice QCD is proposed. Its
connection to the multifermion model is established. A possibility of using
this action for computer simulations is discussed.

</DOC>
<DOC>
<DOCNO> 101703 </DOCNO>
Upon h-normal \Gamma-linear connections on J^1(T,M)


  The paper introduces the notion of h-normal \Gamma-linear connection \nabla
on 1-jet fibre bundle J^1(T,M), and studies its local d-torsions and
d-curvatures togheter with theirs Bianchi identities. Also, it presents the
important deflection d-tensors identities attached to \nabla.

</DOC>
<DOC>
<DOCNO> 119726 </DOCNO>
Constraints on source and lens parameters from microlensing variability


  From regular monitoring of the Double Quasar QSO 0957+561 A,B there is now
general agreement on a time delay of about 416 days. This has made it possible
to determine the microlensing residual in the light-curve, see Pelt et al.
(1998). We have used two significant microlensing features: 1) A ``quiet''
period with a variability less than 0.05 mag lasting about 8 years, and 2) A
change in the residual of 0.25 mag during a time interval of about 5 years. The
first feature gives a lower limit for the lens mass, 'M', for a given
normalized source radius, 'r', whereas the second feature gives an upper limit.
We have considered the amount of mass in a continuum to be a free parameter
with possible values between 0% (all mass in lenses) and 90%. At a significance
level of 1% the mass can only be constrained within a rather wide range (1e-06
M_solar to 5 M_solar). For the radius 'R' of the source an upper limit of 1e16
cm is found, whereas the normalized source radius 'r' is restricted to be
smaller than 30. At a level of 10%, however, the range of possible masses is
much narrower (2e-03 M_solar to 0.5 M_solar), and the upper limit of R is about
6e15 cm, whereas the value of 'r' is restricted to be less than 2. We have used
an effective transverse velocity 'V' equal to 600 km/s.

</DOC>
<DOC>
<DOCNO> 68515 </DOCNO>
Graviton Propagators, Brane Bending and Bending of Light in Theories


  We derive the graviton propagator on the brane for theories with
quasi-localized gravity. In these models the ordinary 4D graviton is replaced
by a resonance in the spectrum of massive Kaluza-Klein modes, which can decay
into the extra dimension. We find that the effects of the extra polarization in
the massive graviton propagator is exactly cancelled by the bending of the
brane due to the matter sources, up to small corrections proportional to the
width of the resonance. Thus at intermediate scales the classic predictions of
Einstein's gravity are reproduced in these models to arbitrary precision.

</DOC>
<DOC>
<DOCNO> 102270 </DOCNO>
Newton polygon and string diagram


  In this work, we discuss graph like image of curves under moment maps and
their relation with the Newton polygon of the curve, which has applications to
Lagrangian torus fibration of Calabi-Yau manifolds.

</DOC>
<DOC>
<DOCNO> 151351 </DOCNO>
Quantum Groups and Noncommutative Geometry


  Quantum groups emerged in the latter quarter of the 20th century as, on the
one hand, a deep and natural generalisation of symmetry groups for certain
integrable systems, and on the other as part of a generalisation of geometry
itself powerful enough to make sense in the quantum domain. Just as the last
century saw the birth of classical geometry, so the present century sees at its
end the birth of this quantum or noncommutative geometry, both as an elegant
mathematical reality and in the form of the first theoretical predictions for
Planck-scale physics via ongoing astronomical measurements. Noncommutativity of
spacetime, in particular, amounts to a postulated new force or physical effect
called cogravity.

</DOC>
<DOC>
<DOCNO> 102187 </DOCNO>
On the structure of open-closed topological field theory in two


  I discuss the general formalism of two-dimensional topological field theories
defined on open-closed oriented Riemann surfaces, starting from an extension of
Segal's geometric axioms. Exploiting the topological sewing constraints allows
for the identification of the algebraic structure governing such systems. I
give a careful treatment of bulk-boundary and boundary-bulk correspondences,
which are responsible for the relation between the closed and open sectors. The
fact that these correspondences need not be injective nor surjective has
interesting implications for the problem of classifying `boundary conditions'.
In particular, I give a clear geometric derivation of the (topological)
boundary state formalism and point out some of its limitations. Finally, I
formulate the problem of classifying (on-shell) boundary extensions of a given
closed topological field theory in purely algebraic terms and discuss
reducibility of boundary extensions.

</DOC>
<DOC>
<DOCNO> 40681 </DOCNO>
A New Prediction for Direct CP Violation \epsilon'/\epsilon and \Delta I


  The low energy dynamics of QCD is investigated with special attention paid to
the matching between QCD and chiral perturbation theory(ChPT), and also to some
useful algebraic chiral operator relations which survive even when we include
chiral loop corrections. It then allows us to evaluate the hadronic matrix
elements below the energy scale $\Lambda_{\chi} \simeq 1$ GeV. Based on the new
analyzes, we present a consistent prediction for both direct CP-violating
parameter $\epsilon'/\epsilon$ and $\Delta I =1/2$ rule in the kaon decays. In
the leading $1/N_c$ approximation, the isospin amplitudes $A_0$ and $A_2$ are
found to agree well with the data, and the direct CP-violating parameter
$\epsilon'/\epsilon$ is predicted to be large, which also confirms our early
conclusion. Its numerical value is $\epsilon'/\epsilon =
23.6^{+12.4}_{-7.8}\times 10^{-4}(Im\lambda_t/1.2\times 10^{-4})$ which is no
longer sensitive to the strange quark mass due to the matching conditions.
Taking into account a simultaneous consistent analysis on the isospin
amplitudes $A_0$ and $A_2$, the ratio $\epsilon'/\epsilon$ is in favor of the
values $\epsilon'/\epsilon = (20\pm 9)\times 10^{-4}$.

</DOC>
<DOC>
<DOCNO> 150477 </DOCNO>
Gauge theories in local causal perturbation theory


  In this thesis quantum gauge theories are considered in the framework of
local, causal perturbation theory. Gauge invariance is described in terms of
the BRS formalism. Local interacting field operators are constructed
perturbatively and field equations are established. A nilpotent BRS
transformation is defined on the local algebra of fields. It allows the
definition of the algebra of local observables as an operator cohomology. This
algebra of local observables can be represented in a Hilbert space.
  The interacting field operators are defined in terms of time ordered products
of free field operators. For the results above to hold the time ordered
products must satisfy certain normalization conditions. To formulate these
conditions also for field operators that contain a spacetime derivative a
suitable mathematical description of time ordered products is developed.
  Among the normalization conditions are Ward identities for the ghost current
and the BRS current. The latter are generalizations of a normalization
condition that is postulated by D"utsch, Hurth, Krahe and Scharf for Yang-Mills
theory. It is not yet proven that this condition has a solution in every order.
All other normalization conditions can be accomplished simultaneously.
  A principle for the correspondence between interacting quantum fields and
interacting classical fields is established. Quantum electrodynamics and
Yang-Mills theory are examined and the results are compared with the
literature.

</DOC>
<DOC>
<DOCNO> 8822 </DOCNO>
Dynamic Approach to Weak First Order Phase Transitions


  A short-time dynamic approach to weak first order phase transitions is
proposed. Taking the 2-dimensional Potts models as examples, from short-time
behaviour of non-equilibrium relaxational processes starting from high
temperature and zero temperature states,x pseudo critical points K^{*} and
K^{**} are determined. A clear difference of the values for K^{*} and K^{**}
distinguishes a weak first order transition from a second order one. At the
pseudo critical points, pseudo critical exponents can be estimated.

</DOC>
<DOC>
<DOCNO> 68586 </DOCNO>
Single chargino production with R-parity lepton number violation in


  We examine single chargino production in conjunction with R-parity lepton
number violation in future lepton-lepton collisions. Present bounds on R-parity
violating couplings allow for a production cross section of the order of
${\cal{O}} (10 {fb})$ for a wide range of sneutrino and chargino masses.
Scenarios of chargino decay which lead to purely leptonic signals in the final
state and without missing energy are also discussed.

</DOC>
<DOC>
<DOCNO> 117226 </DOCNO>
Neutrino flux in the rotating reference frame


  It is considered neutrino flux in the rotating reference frame. Due to the
rotation of the frame, neutrino is observed as a superposition of two states
P-transformed one from another. Since P-transformation is forbidden for
neutrino, in the rotating reference frame one can detect a half of neutrino
flux. Due to the rotation of the earth, the detector of neutrinos can measure a
half of the solar neutrino flux predicted by the SSM that may provide a
solution for the solar neutrino puzzle.

</DOC>
<DOC>
<DOCNO> 40365 </DOCNO>
Implementation of the Dead-Time Free F1 TDC in the COMPASS Detector


  In the scope of the COMPASS experiment a multi-purpose, high rate capable TDC
with digitisation width of 60 ps has been developed. The integration into the
readout system and the flexible input of the CATCH readout driver is presented.

</DOC>
<DOC>
<DOCNO> 67851 </DOCNO>
Non-Standard Model of the Nucleon Electromagnetic Structure and its


  Unitary and analytic ten-resonance model of the nucleon electromagnetic
(e.m.) structure with canonical normalizations and asymptotics is constructed
on a four-sheeted Riemann surface. It describes well all existing experimental
space-like and time-like data on the nucleon e.m. form factors (ff's),
including also FENICE (Frascati) results on the neutron, for the first time.
This is achieved without any external constraints on the isovector spectral
functions following from the piN-scattering data and pion e.m. ff behaviour
through the unitarity condition. Just opposite, the model itself predicts a
pronounced effect of the two-pion continuum on the isovector spectral functions
revealing the strong enhancement of the left wing of the rho(770)-resonance
close to two-pion threshold. The existence of the fourth excited state of the
rho(770) meson with parameters mass and width equal to 2506 MeV and 700 MeV,
respectively. The isoscalar spectral function behaviours are predicted by the
presented model.

</DOC>
<DOC>
<DOCNO> 67718 </DOCNO>
Chiral phase transition at high temperature and density in the QCD-like


  The chiral phase transition at finite temperature T and/or chemical potential
$\mu$ is studied using the QCD-like theory with a variational approach. The
``QCD-like theory'' means the improved ladder approximation with an infrared
cutoff in terms of a modified running coupling. The form of
Cornwall-Jackiw-Tomboulis effective potential is modified by the use of the
Schwinger-Dyson equation for generally nonzero current quark mass. We then
calculate the effective potential at finite T and/or $\mu$ and investigate the
phase structure in the chiral limit. We have a second-order phase transition at
$T_c=129$ MeV for $\mu=0$ and a first-order one at $\mu_c=422$ MeV for T=0. A
tricritical point in the T-$\mu$ plane is found at T=107 MeV, $\mu=210$ MeV.
The position is close to that of the random matrix model and some version of
the Nambu-Jona-Lasinio model.

</DOC>
<DOC>
<DOCNO> 80773 </DOCNO>
Gluons in the lattice SU(2) classical field


  The SU(2) gluonic correlation functions, glueball effective masses in the
$J^{P}=0^{+}$, $2^{+}$ and $0^{-}$ channels were calculated from the lattice
classical gauge configurations which were obtained by smoothing the thermal
gauge configurations through the improved cooling method. The instanton-induced
attractive force in the $0^{+}$ channel and the repulsive force in the $0^-$
channel are confirmed in the Monte Carlo simulation. There is evidence that the
instanton vacuum contribution to the $0^+$ glueball mass is significant.

</DOC>
<DOC>
<DOCNO> 11671 </DOCNO>
Manifestation of superfluidity in an evolving Bose-condensed gas


  We study the generation of excitations due to an ''impurity''(static
perturbation) placed into an oscillating Bose-condensed gas in the
time-dependent trapping field. It is shown that there are two regions for the
position of the local perturbation. In the first region the condensate flows
around the ''impurity'' without generation of excitations demonstrating
superfluid properties. In the second region the creation of excitations occurs,
at least within a limited time interval, revealing destruction of
superfluidity. The phenomenon can be studied by measuring the damping of
condensate oscillations at different positions of the ''impurity''.

</DOC>
<DOC>
<DOCNO> 84230 </DOCNO>
Do semiclassical zero temperature black holes exist?


  The semiclassical Einstein equations are solved to first order in $\epsilon =
\hbar/M^2$ for the case of a Reissner-Nordstr\"{o}m black hole perturbed by the
vacuum stress-energy of quantized free fields. Massless and massive fields of
spin 0, 1/2, and 1 are considered. We show that in all physically realistic
cases, macroscopic zero temperature black hole solutions do not exist. Any
static zero temperature semiclassical black hole solutions must then be
microscopic and isolated in the space of solutions; they do not join smoothly
onto the classical extreme Reissner-Nordst\"{o}m solution as $\epsilon \to 0$.

</DOC>
<DOC>
<DOCNO> 10913 </DOCNO>
Physical perspectives on the global optimization of atomic clusters


  In this chapter the physical aspects of the global optimization of the
geometry of atomic clusters are elucidated. In particular, I examine the
structural principles that determine the nature of the lowest-energy structure,
the physical reasons why some clusters are especially difficult to optimize and
how the basin-hopping transformation of the potential energy surface enables
these difficult clusters to be optimized.

</DOC>
<DOC>
<DOCNO> 68500 </DOCNO>
Post-Inflationary Reheating


  We study a model for reheating that has been much investigated for parametric
resonance, having a quartic interaction of the scalar inflaton with another
scalar field. Attention is particularly on the quantum excitations of the
inflaton field and the metric perturbation with a smooth transition from
quantum to classical stochastic states, followed through from a specific
inflation model to a state including a relativistic fluid. The scalar fields
enter non-perturbatively but the metric enters perturbatively, and the validity
of this latter is assessed. In this model our work seems to point the large
scale curvature parameter changing.

</DOC>
<DOC>
<DOCNO> 84096 </DOCNO>
The virtual black hole in 2d quantum gravity


  As shown recently (W. Kummer, H. Liebl, D.V. Vassilevich, Nucl. Phys. B 544,
403 (1999)) 2d quantum gravity theories --- including spherically reduced
Einstein-gravity --- after an exact path integral of its geometric part can be
treated perturbatively in the loops of (scalar) matter. Obviously the classical
mechanism of black hole formation should be contained in the tree approximation
of the theory. This is shown to be the case for the scattering of two scalars
through an intermediate state which by its effective black hole mass is
identified as a ``virtual black hole''. The present discussion is restricted to
minimally coupled scalars without and with mass. In the first case the
probability amplitude diverges, except the black hole is ``plugged'' by a
suitable boundary condition. For massive scalars a finite S-matrix element is
obtained.

</DOC>
<DOC>
<DOCNO> 10509 </DOCNO>
A gauge invariant exact renormalization group II


  A manifestly gauge invariant and regularized renormalization group flow
equation is constructed for pure SU(N) gauge theory in the large N limit. In
this way we make precise and concrete the notion of a non-perturbative gauge
invariant continuum Wilsonian effective action. Manifestly gauge invariant
calculations may be performed, without gauge fixing, and receive a natural
interpretation in terms of fluctuating Wilson loops. Regularization is achieved
by covariant higher derivatives and by embedding in a spontaneously broken
SU(N|N) supergauge theory; the resulting heavy fermionic vectors are
Pauli-Villars fields. We prove the finiteness of this method to one loop and
any number of external gauge fields. A duality is uncovered that changes the
sign of the squared coupling constant. As a test of the basic formalism we
compute the one loop beta function, for the first time without any gauge
fixing, and prove its universality with respect to cutoff function.

</DOC>
<DOC>
<DOCNO> 13806 </DOCNO>
Anisotropic scattering and quantum magnetoresistivities of a


  We calculate the longitudinal conductivities of a two-dimensional
noninteracting electron gas in a uniform magnetic field and a lateral electric
or magnetic periodic modulation in one spatial direction, in the quantum
regime. We consider the effects of the electron-impurity scattering anisotropy
through the vertex corrections on the Kubo formula, which are calculated with
the Bethe-Salpeter equation, in the self-consistent Born approximation. We find
that due to the scattering anisotropy the band conductivity increases, and the
scattering conductivities decrease and become anisotropic. Our results are in
qualitative agreement with recent experiments.

</DOC>
<DOC>
<DOCNO> 71998 </DOCNO>
Neutrino propagation in matter and CP violation


  We point out that the dependence on the order of the matter through which
neutrinos pass can provide a window into CP violation in the neutrino sector.
This allows for study of CP in the neutrino sector without the necessity of
making a comparison between the behavior of neutrinos and that of
antineutrinos.

</DOC>
<DOC>
<DOCNO> 100615 </DOCNO>
Isoscattering Schottky Manifolds


  The authors exhibit pairs of infinite-volume, hyperbolic three-manifolds that
have the same scattering poles and conformally equivalent boundaries, but which
are not isometric. The examples are constructed using Schottky groups and the
Sunada construction.

</DOC>
<DOC>
<DOCNO> 151595 </DOCNO>
Noncommutative Tachyonic Solitons. Interaction with Gauge Field


  We show that in the presence of U(1) noncommutative gauge interaction the
noncommutative tachyonic system exhibits solitonic solutions for finite value
of the noncommutativity parameter.

</DOC>
<DOC>
<DOCNO> 13356 </DOCNO>
Localization of a polymer in random media: Relation to the localization


  In this paper we consider in detail the connection between the problem of a
polymer in a random medium and that of a quantum particle in a random
potential. We are interested in a system of finite volume where the polymer is
known to be {\it localized} inside a low minimum of the potential. We show how
the end-to-end distance of a polymer which is free to move can be obtained from
the density of states of the quantum particle using extreme value statistics.
We give a physical interpretation to the recently discovered one-step
replica-symmetry-breaking solution for the polymer (Phys. Rev. E{\bf 61}, 1729
(2000)) in terms of the statistics of localized tail states. Numerical
solutions of the variational equations for chains of different length are
performed and compared with quenched averages computed directly by using the
eigenfunctions and eigenenergies of the Schr\"odinger equation for a particle
in a one-dimensional random potential. The quantities investigated are the
radius of gyration of a free gaussian chain, its mean square distance from the
origin and the end-to-end distance of a tethered chain. The probability
distribution for the position of the chain is also investigated. The glassiness
of the system is explained and is estimated from the variance of the measured
quantities.

</DOC>
<DOC>
<DOCNO> 68689 </DOCNO>
Cosmology of Brane-Bulk Models in Five Dimensions


  We study the cosmology of models with four space and one time dimension where
our universe is a 3-brane and report a few results which extend existing work
in several directions. Assuming a stable fifth dimension, we obtain a solution
for the metric, which does not depend on any arbitrary parameters. We discuss
some implications of this result.

</DOC>
<DOC>
<DOCNO> 40129 </DOCNO>
Baryonic resonances mass spectrum from a modified perturbative QCD


  A recently proposed modified perturbation expansion for QCD is employed to
evaluate the quark self-energies. Results of the order of 1/3 of the nucleon
mass are obtained for the effective masses of the up and down quarks in a first
approximation. Also, the predicted flavor dependence of the calculated quarks
masses turns out to be the appropriate to well reproduce the spectrum of the
ground states within the various groups of hadronic resonances through the
simple addition of the evaluated constituent quark masses. The results suggests
to conjecture that the modified expansion, after also introducing quark
condensates in a same token as the gluonic ones, would be able to furnish a
natural explanation of the mass spectrum of the three generations of
fundamental fermions.

</DOC>
<DOC>
<DOCNO> 178459 </DOCNO>
Coupled $\Lambda N-\Sigma N$ and $\Lambda NN-\Sigma NN$ systems and


  This paper summarizes our studies of the hypertriton and describes our
findings on the hyperon-nucleon interaction, especially on the role of the
$\Lambda N-\Sigma N$ coupling and the strengths of the $S$-wave $YN$
interactions. We briefly comment on our ongoing analyses with electromagnetic
probes.

</DOC>
<DOC>
<DOCNO> 117050 </DOCNO>
Orientational melting of two-shell carbon nanoparticles: molecular


  The energetic characteristics of two-shell carbon nanoparticles ("onions")
with different shapes of second shell are calculated. The barriers of relative
rotation of shells are found to be surprisingly small; therefore, free relative
rotation of shells can take place at room temperature. The intershell
orientational melting of the nanoparticle $C_{60}@C_{240}$ is studied by
molecular dynamics. The parameters of Arrhenius formula for jump rotational
intershell diffusion are calculated. The definition of orientational melting
temperature is proposed as the temperature when the transition probability over
barrier between equivalent potential minima is equal to 1/2. The temperature of
orientational melting of the nanoparticle $C_{60}@C_{240}$ is about 60 K.

</DOC>
<DOC>
<DOCNO> 83042 </DOCNO>
Exploiting Syntactic Structure for Natural Language Modeling


  The thesis presents an attempt at using the syntactic structure in natural
language for improved language models for speech recognition. The structured
language model merges techniques in automatic parsing and language modeling
using an original probabilistic parameterization of a shift-reduce parser. A
maximum likelihood reestimation procedure belonging to the class of
expectation-maximization algorithms is employed for training the model.
Experiments on the Wall Street Journal, Switchboard and Broadcast News corpora
show improvement in both perplexity and word error rate - word lattice
rescoring - over the standard 3-gram language model. The significance of the
thesis lies in presenting an original approach to language modeling that uses
the hierarchical - syntactic - structure in natural language to improve on
current 3-gram modeling techniques for large vocabulary speech recognition.

</DOC>
<DOC>
<DOCNO> 85114 </DOCNO>
Equations of Motion of Spinning Relativistic Particles


  The motion of spinning relativistic particles in external electromagnetic and
gravitational fields is considered. Covariant equations for this motion are
demonstrated to possess pathological solutions, when treated nonperturbatively
in spin. A self-consistent approach to the problem is formulated, based on the
noncovariant description of spin and on the usual, ``naive'' definition of the
coordinate of a relativistic particle. A simple description of the
gravitational interaction of first order in spin, is pointed out for a
relativistic particle. The approach developed allows one to consider effects of
higher order in spin. Explicit expression for the second-order Hamiltonian is
presented. We discuss the gravimagnetic moment, which is a special spin effect
in general relativity.

</DOC>
<DOC>
<DOCNO> 101421 </DOCNO>
On the geometry of generalized Chaplygin systems


  Some aspects of the geometry and the dynamics of generalized Chaplygin
systems are investigated. First, two different but complementary approaches to
the construction of the reduced dynamics are reviewed: a symplectic approach
and an approach based on the theory of affine connections. Both are mutually
compared and further completed. Next, a necessary and sufficient condition is
derived for the existence of an invariant measure for the reduced dynamics of
generalized Chaplygin systems of mechanical type. A simple example is then
constructed of a generalized Chaplygin system which does not verify this
condition, thereby answering in the negative a question raised by Koiller.

</DOC>
<DOC>
<DOCNO> 120653 </DOCNO>
The cluster environments of the z~1 3CR radio galaxies


  An analysis of the environments around a sample of 28 3CR radio galaxies with
redshifts 0.6 < z < 1.8 is presented, based primarily upon K--band images down
to K ~ 20 taken using the UK Infrared Telescope (UKIRT). A net overdensity of
K-band galaxies is found in the fields of the radio galaxies, with the mean
excess counts being comparable to that expected for clusters of Abell Class 0
richness. A sharp peak is found in the angular cross-correlation amplitude
centred on the radio galaxies, which, for reasonable assumptions about the
luminosity function of the galaxies, corresponds to a spatial cross-correlation
amplitude between those determined for low redshift Abell Class 0 and Abell
Class 1 clusters.

</DOC>
<DOC>
<DOCNO> 117293 </DOCNO>
Coherent Transport


  We discuss the transport of matter waves in low-dimensional waveguides. Due
to scattering from uncontrollable noise fields, the spatial coherence gets
reduced and eventually lost. We develop a description of this decoherence
process in terms of transport equations for the atomic Wigner function. We
outline its derivation and discuss the special case of white noise where an
analytical solution can be found.

</DOC>
<DOC>
<DOCNO> 8130 </DOCNO>
Rotating Atomic Traps for Bosons and the Centrifuge Effect


  A rigorous time independent Hamiltonian for rotating atomic traps is
discussed. The steady states carry a mass current and thereby an angular
momentum. It is shown that the rotation positions the atoms away from the
rotation axis (after taking both the time and quantum mechanical averages) as
in a conventional centrifuge. Some assert that the rotation for Bose
condensates cause the atoms to move towards the rotation axis; i.e. act
oppositely to fluids in a centrifuge. The opposing physical pictures are
reminiscent of the difference between the rotational motion views of Newton and
Cassini.

</DOC>
<DOC>
<DOCNO> 11299 </DOCNO>
Chern-Simons Theory and Quantum Fields in the Lowest Landau Level


  By considering the area preserving geometric transformations in the
configuration space of electrons moving in the lowest Landau level (LLL) we
arrive at the Chern-Simons type Lagrangian. Imposing the LLL condition, we get
a scheme with the complex gauge fields and transformations. Quantum theory for
the matter field in LLL is considered and formal expressions for Read's
operator and Laughlin wave function are presented in the second quantized form.

</DOC>
<DOC>
<DOCNO> 123135 </DOCNO>
Dark Halo and Disk Galaxy Scaling Laws


  I highlight recent progress in our understanding of the origin of disk galaxy
scaling laws in a hierarchically clustering universe. Numerical simulations of
galaxy formation in Cold Dark Matter (CDM) dominated universes indicate that
the slope and scatter of the I-band Tully-Fisher (TF) relation are well
reproduced in this model, although not, as proposed in recent work, because of
the cosmological equivalence between halo mass and circular velocity, but
rather as a result of the dynamical response of the halo to the assembly of the
luminous component of the galaxy. The zero-point of the TF relation is
determined mainly by the stellar mass-to-light ratio ($\Upsilon_I$) as well as
by the concentration ($c$) of the dark halo. For $c \sim 10$, as is typical of
halos formed in the ``concordance'' $\Lambda$CDM model, we find that this
requires $\Upsilon_I \sim 1.5$, in reasonable agreement with the mass-to-light
ratios expected of stellar populations with colors similar to those of TF
galaxies. This conclusion supersedes that of Navarro & Steinmetz (2000a,b), who
claimed the $\Lambda$CDM halos were too concentrated to be consistent with the
observed TF relation. The disagreement can be traced to inconsistencies in the
normalization of the power spectrum used in that work. Our new results show
that simulated disk galaxies in the $\Lambda$CDM scenario are not clearly
inconsistent with the observed I-band Tully-Fisher relation. On the other
hand,their angular momenta is much lower than observed. Accounting
simultaneously for the spin, size and luminosity of disk galaxies remains a
challenge for hierarchical models of galaxy formation.

</DOC>
<DOC>
<DOCNO> 11076 </DOCNO>
Thermodynamic and structural aspects of the potential energy surface of


  Relations between the thermodynamics and dynamics of supercooled liquids
approaching a glass transition have been proposed over many years. The
potential energy surface of model liquids has been increasingly studied since
it provides a connection between the configurational component of the partition
function on one hand, and the system dynamics on the other. This connection is
most obvious at low temperatures, where the motion of the system can be
partitioned into vibrations within a basin of attraction and infrequent
inter-basin transitions. In this work, we present a description of the
potential energy surface properties of supercooled liquid water. The dynamics
of this model has been studied in great details in the last years.
Specifically, we locate the minima sampled by the liquid by ``quenches'' from
equilibrium configurations generated via molecular dynamics simulations. We
calculate the temperature and density dependence of the basin energy,
degeneracy, and shape. The temperature dependence of the energy of the minima
is qualitatively similar to simple liquids, but has anomalous density
dependence. The unusual density dependence is also reflected in the
configurational entropy, the thermodynamic measure of degeneracy. Finally, we
study the structure of simulated water at the minima, which provides insight on
the progressive tetrahedral ordering of the liquid on cooling.

</DOC>
<DOC>
<DOCNO> 68331 </DOCNO>
A note on spectator effects and quark-hadron duality in inclusive beauty


  In this paper, we evaluate the expectation values of four-quark operators for
the inclusive beauty decays from the differences in the inclusive total decay
rates, assuming that the heavy quark expansion converges at $O(1/m^3)$. The
obtained expectation values yeilds the ratio $\tau(\Lambda_b)/\tau(B)$ close to
the experimental onee. We further point out that the quark-hadron duality
violation would be rather small allowing predictions of inclusive quantities.

</DOC>
<DOC>
<DOCNO> 102752 </DOCNO>
Geometry of chain complexes and outer automorphisms under derived


  The two main theorems proved here are as follows: If $A$ is a finite
dimensional algebra over an algebraically closed field, the identity component
of the algebraic group of outer automorphisms of $A$ is invariant under derived
equivalence. This invariance is obtained as a consequence of the following
generalization of a result of Voigt. Namely, given an appropriate
geometrization $\text{Comp}^A_{\bold d}$ of the family of finite $A$-module
complexes with fixed sequence $\bold d$ of dimensions and an ``almost
projective'' complex $X\in \text{Comp}^A_{\bold d}$, there exists a canonical
vector space embedding $$T_{X}(\text{Comp}^A_{\bold d}) / T_{X}(G.X) \
\longrightarrow \text{Hom}_{D^b (A\text{-Mod})}(X, X[1]),$$ where $G$ is the
pertinent product of general linear groups acting on $\text{Comp}^A_{\bold d}$,
tangent spaces at $X$ are denoted by $T_X(-)$, and $X$ is identified with its
image in the derived category $D^b (A\text{-Mod})$.

</DOC>
<DOC>
<DOCNO> 178810 </DOCNO>
Possible S-wave Dibaryons in SU(3) Chiral Quark Model


  In the framework of the SU(3) chiral quark model, the $S-$wave baryon-baryon
bound states are investigated. It is found that according to the symmetry
character of the system and the contributions from chiral fields, there are
three types of bound states. The states of the first type, such as
$[\Omega\Omega]_{(0,0)}$ and $[\Xi^{*}\Omega]_{(0,1/2)}$ are deeply bound
dibaryon with narrow widths. The second type states, $[\Sigma^{*}
\Delta]_{(0,5/2)}$,$[\Sigma^{*} \Delta]_{(3,1/2)}$, $[\Delta\Delta]_{(0,3)}$
and $[\Delta\Delta]_{(3,0)}$ are also bound states, but with broad widths.
$[\Xi\Omega - \Xi^{*}\Omega]_{(1,1/2)}$, $[\Xi\Xi]_{(0,1)}$, and $[N
\Omega]_{(2,1/2)}$ are third type states. They, like {\em d}, are weakly bound
only if the chiral fields can provide attraction between baryons.

</DOC>
<DOC>
<DOCNO> 70638 </DOCNO>
Cosmological consequences of the brane/bulk interaction


  We investigate cosmological consequences arising from the interaction between
a homogeneous and isotropic brane-universe and the bulk. A Friedmann equation
is derived which incorporates both the brane and bulk matter contributions,
which are both assumed to be of arbitrary fluid form. In particular, new terms
arise which describe the energy flow onto (or away from) the brane, as well as
changes of the equation of state in the bulk. We discuss Randall-Sundrum type
models as well as dilatonic domain walls and carefully consider the conditions
for stabilising the induced gravitational constant. Furthermore, consequences
for cosmological perturbations are analysed. We show that, in general,
super-horizon amplitudes are not constant.

</DOC>
<DOC>
<DOCNO> 71642 </DOCNO>
Isgur--Wise function in a relativistic model of constituent quarks


  The integral representation for Isgur -- Wise function (IWF) is obtained in
the framework of instant--form relativistic Hamiltonian dynamics for mesons
with one heavy quark. The upper and lower limits are calculated for the slope
parameter of IWF $\rho^2$ by the model independent way. IWF is calculated for
different wave functions of quarks in the meson. The difference between the
limits of $\rho^2$ equals 1/3. The constraint on the slope parameter is in a
good agreement with experiments. The weak dependence of IWF on the choice of
wave functions is found.

</DOC>
<DOC>
<DOCNO> 151712 </DOCNO>
5D Actions for 6D Self-Dual Tensor Field Theory


  We present two equivalent five-dimensional actions for six-dimensional (N,0)
N=1,2 supersymmetric theories of self-dual tensor whose one spatial dimension
is compactified on a circle. The Kaluza-Klein tower consists of a massless
vector and infinite number of massive self-dual tensor multiplets living in
five-dimensions. The self-duality follows from the equation of motion. Both
actions are quadratic in field variables without any auxiliary field. When
lifted back to six-dimensions, one of them gives a supersymmetric extension of
the bosonic formulation for the chiral two-form tensor by Perry and Schwarz.

</DOC>
<DOC>
<DOCNO> 151063 </DOCNO>
Space/Time Non-Commutativity and Causality


  Field theories based on non-commutative spacetimes exhibit very distinctive
nonlocal effects which mix the ultraviolet with the infrared in bizarre ways.
In particular if the time coordinate is involved in the non-commutativity the
theory seems to be seriously acausal and inconsistent with conventional
Hamiltonian evolution. To illustrate these effects we study the scattering of
wave packets in a field theory with space/time non-commutativity. In this
theory we find effects which seem to precede their causes and rigid rods which
grow instead of Lorentz contract as they are boosted. These field theories are
evidently inconsistent and violate causality and unitarity. On the other hand
open string theory in a background electric field is expected to exhibit
space/time non-commutativity. This raises the question of whether they also
lead to acausal behavior. We show that this is not the case. Stringy effects
conspire to cancel the acausal effects that are present for the non-commutative
field theory.

</DOC>
<DOC>
<DOCNO> 101359 </DOCNO>
On Invariants of Morse Knots


  We define and study Vassiliev invariants for (long) Morse knots. It is shown
that there are Vassiliev invariants which can distinguish some topologically
equivalent Morse knots. In particular, there is an invariant of order 3 for
Morse knots with one maximum that distinguishes two different representations
of the figure eight knot. We also present the results of computer calculations
for some invariants of low order. It turns out that for Morse knots with two
maxima there is a Z/2-valued invariant of order 6 which is not a reduction of
any integer-valued invariant.

</DOC>
<DOC>
<DOCNO> 120761 </DOCNO>
The 3.4 micron absorption feature towards three obscured active galactic


  The results of 3-4 $\mu$m spectroscopy towards the nuclei of NGC 3094, NGC
7172, and NGC 7479 are reported. In ground-based 8-13 $\mu$m spectra, all the
sources have strong absorption-like features at $\sim$10 $\mu$m, but they do
not have detectable polycyclic aromatic hydrocarbon (PAH) emission features.
The 3.4 $\mu$m carbonaceous dust absorption features are detected towards all
nuclei. NGC 3094 shows a detectable 3.3 $\mu$m PAH emission feature, while NGC
7172 and NGC 7479 do not. Nuclear emission whose spectrum shows dust absorption
features but no PAH emission features is thought to dominated by highly
obscured active galactic nuclei (AGNs) activity. For NGC 7172, NGC 7479, and
three other such nuclei in the literature, we investigate the optical depth
ratios between the 3.4 $\mu$m carbonaceous dust and 9.7 $\mu$m silicate dust
absorption ($\tau_{3.4}$/$\tau_{9.7}$). The $\tau_{3.4}$/$\tau_{9.7}$ ratios
towards three highly obscured AGNs with face-on host galaxies are
systematically larger than the ratios in the Galactic diffuse interstellar
medium or the ratios for two highly obscured AGNs with edge-on host galaxies.
We suggest that the larger ratios can be explained if the obscuring dust is so
close to the central AGNs that a temperature gradient occurs in it. If this
idea is correct, our results may provide spectroscopic evidence for the
presence of the putative ``dusty tori'' in the close vicinity of AGNs.

</DOC>
<DOC>
<DOCNO> 83469 </DOCNO>
Algorithmic Theories of Everything


  The probability distribution P from which the history of our universe is
sampled represents a theory of everything or TOE. We assume P is formally
describable. Since most (uncountably many) distributions are not, this imposes
a strong inductive bias. We show that P(x) is small for any universe x lacking
a short description, and study the spectrum of TOEs spanned by two Ps, one
reflecting the most compact constructive descriptions, the other the fastest
way of computing everything. The former derives from generalizations of
traditional computability, Solomonoff's algorithmic probability, Kolmogorov
complexity, and objects more random than Chaitin's Omega, the latter from
Levin's universal search and a natural resource-oriented postulate: the
cumulative prior probability of all x incomputable within time t by this
optimal algorithm should be 1/t. Between both Ps we find a universal
cumulatively enumerable measure that dominates traditional enumerable measures;
any such CEM must assign low probability to any universe lacking a short
enumerating program. We derive P-specific consequences for evolving observers,
inductive reasoning, quantum physics, philosophy, and the expected duration of
our universe.

</DOC>
<DOC>
<DOCNO> 121378 </DOCNO>
Finding Pulsars at Parkes


  There are many reasons why it is important to increase the number of known
pulsars. Not only do pulsar searches continue to improve statistical estimates
of, for example, pulsar birthrates, lifetimes and the Galactic distribution,
but they continue to turn up interesting and, in some cases, unique individual
pulsars. In the early days of pulsar astronomy, the Molonglo radio telescope
led the world as a pulsar detection instrument. However, the Parkes radio
telescope, with its frequency versatility and greater tracking ablility,
combined with sensitive receivers and powerful computer detection algorithms,
is now the world's most successful telescope at finding pulsars. The Parkes
multibeam survey, begun in 1997, by itself will come close to doubling the
number of known pulsars. Parkes has also been very successful at finding
millisecond pulsars, especially in globular clusters. One third of the known
millisecond pulsars have been found in just one cluster, 47 Tucanae.

</DOC>
<DOC>
<DOCNO> 116480 </DOCNO>
Efficient Methods for Handling Long-Range Forces in Particle-Particle


  A number of problems arise when long-range forces, such as those governed by
Bessel functions, are used in particle-particle simulations. If a simple
cut-off for the interaction is used, the system may find an equilibrium
configuration at zero temperature that is not a regular lattice yet has an
energy lower than the theoretically predicted minimum for the physical system.
We demonstrate two methods to overcome these problems in Monte Carlo and
molecular dynamics simulations. The first uses a smoothed potential to truncate
the interaction in a single unit cell: this is appropriate for phenomenological
characterisations, but may be applied to any potential. The second is a new
method for summing the unmodified potential in an infinitely tiled periodic
system, which is in excess of 20,000 times faster than previous naive methods
which add periodic images in shells of increasing radius: this is suitable for
quantitative studies. Finally we show that numerical experiments which do not
handle the long-range force carefully may give misleading results: both of our
proposed methods overcome these problems.

</DOC>
<DOC>
<DOCNO> 170212 </DOCNO>
The Violation of Bell Inequalities in the Macroworld


  We show that Bell inequalities can be violated in the macroscopic world. The
macroworld violation is illustrated using an example involving connected
vessels of water. We show that whether the violation of inequalities occurs in
the microworld or in the macroworld, it is the identification of nonidentical
events that plays a crucial role. Specifically, we prove that if nonidentical
events are consistently differentiated, Bell-type Pitowsky inequalities are no
longer violated, even for Bohm's example of two entangled spin 1/2 quantum
particles. We show how Bell inequalities can be violated in cognition,
specifically in the relationship between abstract concepts and specific
instances of these concepts. This supports the hypothesis that genuine quantum
structure exists in the mind. We introduce a model where the amount of
nonlocality and the degree of quantum uncertainty are parameterized, and
demonstrate that increasing nonlocality increases the degree of violation,
while increasing quantum uncertainty decreases the degree of violation.

</DOC>
<DOC>
<DOCNO> 100147 </DOCNO>
Capacity of Quantum Channels Using Product Measurements


  The capacity of a quantum channel for transmission of classical information
depends in principle on whether product states or entangled states are used at
the input, and whether product or entangled measurements are used at the
output. We show that when product measurements are used, the capacity of the
channel is achieved with product input states, so that entangled inputs do not
increase capacity. We show that this result continues to hold if sequential
measurements are allowed, whereby the choice of successive measurements may
depend on the results of previous measurements.
  We also present a new simplified expression which gives an upper bound for
the Shannon capacity of a channel, and which bears a striking resemblance to
the well-known Holevo bound.

</DOC>
<DOC>
<DOCNO> 118151 </DOCNO>
A New Parameter In Accretion Disk Model


  Taking optically thin accretion flows as an example, we investigate the
dynamics and the emergent spectra of accretion flows with different outer
boundary conditions (OBCs) and find that OBC plays an important role in
accretion disk model. This is because the accretion equations describing the
behavior of accretion flows are a set of {\em differential} equations,
therefore, accretion is intrinsically an initial-value problem. We argue that
optically thick accretion flow should also show OBC-dependent behavior. The
result means that we should seriously consider the initial physical state of
the accretion flow such as its angular momentum and its temperature. An
application example to Sgr A$^*$ is presented.

</DOC>
<DOC>
<DOCNO> 12954 </DOCNO>
Coupled Cluster Treatment Of An Interpolating Triangle/Kagome


  The coupled cluster method (CCM) is applied to a spin-half model at zero
temperature which interpolates between a triangular lattice antiferromagnet
(TAF) and a Kagome lattice antiferromagnet (KAF). The strength of the bonds
which connect Kagome lattice sites is J, and the strength of the bonds which
link the non-Kagome lattice sites to the Kagome lattice sites on an underlying
triangular lattice is J'. Our results are found to be highly converged, and our
best estimate for the ground-state energy per spin for the spin-half KAF (J'=0)
of -0.4252 constitutes one of the most accurate results yet found for this
model. The amount of classical ordering on the Kagome lattice sites is also
considered, and it is seen that this parameter goes to zero for values of J'
very close the KAF point. Further evidence is also presented for CCM critical
points which reinforce the conjecture that there is a phase near to the KAF
point which is much different to that near to the TAF point (J=J').

</DOC>
<DOC>
<DOCNO> 85140 </DOCNO>
Expansion-induced contribution to the precession of binary orbits


  We point out the existence of new effects of global spacetime expansion on
local binary systems. In addition to a possible change of orbital size, there
is a contribution to the precession of elliptic orbits, to be added to the
well-known general relativistic effect in static spacetimes, and the
eccentricity can change. Our model calculations are done using geodesics in a
McVittie metric, representing a localized system in an asymptotically
Robertson-Walker spacetime; we give a few numerical estimates for that case,
and indicate ways in which the model should be improved.

</DOC>
<DOC>
<DOCNO> 100389 </DOCNO>
Variational methods, multisymplectic geometry and continuum mechanics


  This paper presents a variational and multisymplectic formulation of both
compressible and incompressible models of continuum mechanics on general
Riemannian manifolds. A general formalism is developed for non-relativistic
first-order multisymplectic field theories with constraints, such as the
incompressibility constraint. The results obtained in this paper set the stage
for multisymplectic reduction and for the further development of Veselov-type
multisymplectic discretizations and numerical algorithms. The latter will be
the subject of a companion paper.

</DOC>
<DOC>
<DOCNO> 11883 </DOCNO>
Magnetic field effects on quantum ring excitons


  We study the effect of magnetic field and geometric confinement on excitons
confined to a quantum ring. We use analytical matrix elements of the Coulomb
interaction and diagonalize numerically the effective-mass Hamiltonian of the
problem. To explore the role of different boundary conditions, we investigate
the quantum ring structure with a parabolic confinement potential, which allows
the wavefunctions to be expressed in terms of center of mass and relative
degrees of freedom of the exciton. On the other hand, wavefunctions expressed
in terms of Bessel functions for electron and hole are used for a hard-wall
confinement potential. The binding energy and electron-hole separation of the
exciton are calculated as function of the width of the ring and the strength of
a external magnetic field. The linear optical susceptibility as a function of
magnetic fields is also discussed. We explore the Coulomb electron-hole
correlation and magnetic confinement for several ring width and size
combinations. The Aharanov-Bohm oscillations of exciton characteristics
predicted for one-dimensional rings are found to not be present in these
finite-width systems.

</DOC>
<DOC>
<DOCNO> 8372 </DOCNO>
Temperature dependent changes of the Mn 3d and 4p bands near T$_c$ in


  We report high-resolution X-ray Absorption Near Edge Structure (XANES)
measurements at the Mn K-edge as a function of temperature, for
La$_{1-x}$Ca$_x$MnO$_3$ samples, with a focus mainly on the pre-edge region.
Small peaks labeled A$_1$-A$_3$ are observed which corresponds to 1s-3d
dipole-transitions, made weakly allowed via a hybridization of Mn 4p states
with Mn 3d states on {\it neighboring} atoms. Adjusting the parameters in an
LSDA calculation to approximately match the experimental A$_1$-A$_2$ splitting
yields U = 4 eV and J$_H$ = 0.7 eV. For colossal magnetoresistance samples,
A$_1$ decreases with T while A$_2$ increases with T below T$_c$, which shows
that the 3d bands change significant as T moves through T$_c$. There are also
small changes in the shape of the main edge (1s-4p transitions).

</DOC>
<DOC>
<DOCNO> 9302 </DOCNO>
Thermodynamic Properties of Three-Dimensional Orthogonal Dimer Model for


  Effects of the inter-layer couplings for the orthogonal dimer system
SrCu$_2$(BO$_3$)$_2$ are discussed. The spin-gap $\Delta$ of the
three-dimensional model is independent of the inter-layer couplings when they
are small. Therefore at low temperatures ($T < \Delta$) thermodynamic
properties are described well by the two-dimensional model. On the other hand
at high temperatures the mean-field type scaling ansatz is useful to discuss
the magnetic susceptibility for week inter-layer couplings.
  From fit of the magnetic susceptibility, the estimated coupling constants are
J = 85 K for the nearest-neighbor couplings, $J^{'} = 54$ K for the
next-nearest-neighbor couplings, and $J^{''} = 8$ K for the inter-layer
couplings. These parameters are consistent with the temperature dependence of
the specific heat at low temperatures.

</DOC>
<DOC>
<DOCNO> 119743 </DOCNO>
PSR J1907+0918 - a young radio pulsar near SGR 1900+14 and G42.8+0.6


  We have extensively searched for periodic signals from the soft-gamma
repeater SGR 1900+14, at 430 and 1410 MHz with the Arecibo telescope. Our
observations did not reveal the 5.16-s periodicity discovered at X-ray
wavelengths by Hurley et al. (1998). We place pulsed flux-density upper limits
of 150 and 30 uJy at 430 and 1410 MHz respectively. In the course of the 1410
MHz search we discovered a 226-ms radio pulsar, PSR J1907+0918. Its period
derivative implies that the age of J1907+0918 is only 38 kyr, making it one of
the youngest members of the known pulsar population. Independent lines of
evidence in support of this apparent youth are the unusually high degree of
circular polarization and a relatively flat radio spectrum. The close proximity
of this young radio pulsar to the supernova remnant G42.8+0.6 poses a problem
for the proposed association between the G42.8+0.6 and SGR 1900+14.

</DOC>
<DOC>
<DOCNO> 120160 </DOCNO>
Star formation in expanding shells


  We discuss the induced star formation in dense walls of expanding shells. The
fragmentation process is studied using the linear perturbation theory. The
influence of the energy input, the ISM distribution and the ISM speed of sound
is examined analytically and by numerical simulations. We formulate the
universal condition for the gravitational fragmentation of expanding shells: if
the total surface density of the disk is higher than a certain critical value,
shells are unstable. The value of the critical density depends on the energy of
the shell and the sound speed in the ISM.

</DOC>
<DOC>
<DOCNO> 11715 </DOCNO>
Nonperturbative Renormalization Flow and Essential Scaling for the


  The Kosterlitz-Thouless phase transition is described by the nonperturbative
renormalization flow of the two dimensional $\phi^4$-model. The observation of
essential scaling demonstrates that the flow equation incorporates
nonperturbative effects which have previously found an alternative description
in terms of vortices. The duality between the linear and nonlinear
$\sigma$-model gives a unified description of the long distance behaviour for
O(N)-models in arbitrary dimension $d$. We compute critical exponents in first
order in the derivative expansion.

</DOC>
<DOC>
<DOCNO> 151644 </DOCNO>
Large branes in AdS and their field theory dual


  Recently it was suggested that a graviton in $AdS_5 \times S^5$ with a large
momentum along the sphere can blow up into a spherical D-brane in $S^5$. In
this paper we show that the same graviton can also blow up into a spherical
D-brane in $AdS_5$ with exactly the same quantum numbers (angular momentum and
energy). These branes are BPS, preserving 16 of the 32 supersymmetries. We show
that there is a BPS {\it classical} solution for SYM on $S^3\times R$ with
exactly the same quantum numbers. The solution has non-vanishing Higgs
expectation values and hence is dual to the large brane in AdS.

</DOC>
<DOC>
<DOCNO> 151696 </DOCNO>
The Enhancon and N=2 Gauge Theory/Gravity RG Flows


  We study the family of ten dimensional type IIB supergravity solutions
corresponding to renormalisation group flows from N=4 to N=2 supersymmetric
Yang-Mills theory. Part of the solution set corresponds to a submanifold of the
Coulomb branch of the gauge theory, and we use a D3-brane probe to uncover
details of this physics. At generic places where supergravity is singular, the
smooth physics of the probe yields the correct one-loop form of the effective
low energy gauge coupling. The probe becomes tensionless on a ring at finite
radius. Supergravity flows which end on this ``enhancon'' ring correspond to
the vacua where extra massless degrees of freedom appear in the gauge theory,
and the gauge coupling diverges there. We identify an SL(2,Z) duality action on
the enhancon ring which relates the special vacua, and comment on the massless
dyons within them. We propose that the supergravity solution inside the
enhancon ring should be excised, since the probe's tension is unphysical there.

</DOC>
<DOC>
<DOCNO> 7674 </DOCNO>
Theory of the spin bath


  The quantum dynamics of mesoscopic or macroscopic systems is always
complicated by their coupling to many "environmental" modes.At low T these
environmental effects are dominated by localised modes, such as nuclear and
paramagnetic spins, and defects (which also dominate the entropy and specific
heat). This environment, at low energies, maps onto a "spin bath" model. This
contrasts with "oscillator bath" models (originated by Feynman and Vernon)
which describe {\it delocalised} environmental modes such as electrons,
phonons, photons, magnons, etc. One cannot in general map a spin bath to an
oscillator bath (or vice-versa); they constitute distinct "universality
classes" of quantum environment. We show how the mapping to spin bath models is
made, and then discuss several examples in detail, including moving particles,
magnetic solitons, nanomagnets, and SQUIDs, coupled to nuclear and paramagnetic
spin environments. We show how to average over spin bath modes, using an
operator instanton technique, to find the system dynamics, and give analytic
results for the correlation functions, under various conditions. We then
describe the application of this theory to magnetic and superconducting
systems.Particular attention is given to recent work on tunneling magnetic
macromolecules, where the role of the nuclear spin bath in controlling the
tunneling is very clear; we also discuss other magnetic systems in the quantum
regime, and the influence of nuclear and paramagnetic spins on flux dynamics in
SQUIDs.

</DOC>
<DOC>
<DOCNO> 9071 </DOCNO>
Is there a universality of the helix-coil transition in protein models?


  The similarity in the thermodynamic properties of two completely different
theoretical models for the helix-coil transition is examined critically. The
first model is an all-atomic representation for a poly-alanine chain, while the
second model is a minimal helix-forming model that contains no system
specifics. Key characteristics of the helix-coil transition, in particular, the
effective critical exponents of these two models agree with each other, within
a finite-size scaling analysis.

</DOC>
<DOC>
<DOCNO> 13914 </DOCNO>
Correlated adaptation of agents in a simple market: a statistical


  We discuss recent work in the study of a simple model for the collective
behaviour of diverse speculative agents in an idealized stockmarket, considered
from the perspective of the statistical physics of many-body systems. The only
information about other agents available to any one is the total trade at time
steps. Evidence is presented for correlated adaptation and phase
transitions/crossovers in the global volatility of the system as a function of
appropriate information scaling dimension. Stochastically controlled
irrationally of individual agents is shown to be globally advantageous. We
describe the derivation of the underlying effective stochastic differential
equations which govern the dynamics, and make an interpretation of the results
from the point of view of the statistical physics of disordered systems.

</DOC>
<DOC>
<DOCNO> 122561 </DOCNO>
HST-NICMOS Observations of M31's Metal Rich Globular Clusters and Their


  We have obtained HST-NICMOS observations of five of M31's most metal rich
globular clusters: G1, G170, G174, G177 & G280. For the two clusters farthest
from the nucleus we statistically subtract the field population and estimate
metallicities using K-(J-K) color-magnitude diagrams (CMDs). Based on the
slopes of their infrared giant branches we estimate [Fe/H]=-1.22+/-0.43 for G1
and -0.15+/-0.37 for G280. We combine our infrared observations of G1 with two
epochs of optical HST-WFPC2 V-band data and identify at least one LPV based on
color and variability. The location of G1's giant branch in the K-(V-K) CMD is
very similar to that of M107, indicating a higher metallicity than our purely
infrared CMD: [Fe/H]=-0.9+/-0.2.
  For the field surrounding G280, we estimate the metallicity to be -1.3 with a
spread of 0.5 from the slope and width of the giant branch. Based on the
numbers and luminosities of the brightest giants, we conclude that only a small
fraction of the stars in this field could be as young as 2 Gyr, while the
majority have ages closer to 10 Gyr.
  The K-band luminosity functions (LFs) of the upper few magnitudes of G1 and
G280, as well as for the fields surrounding all clusters, are indistinguishable
from the LF measured in the bulge of our Galaxy. This indicates that these
clusters are very similar to Galactic clusters, and at least in the surrounding
fields observed, there are no significant populations of young luminous stars.

</DOC>
<DOC>
<DOCNO> 12364 </DOCNO>
Dynamics of localization in a waveguide


  This is a review of the dynamics of wave propagation through a disordered
N-mode waveguide in the localized regime. The basic quantities considered are
the Wigner-Smith and single-mode delay times, plus the time-dependent power
spectrum of a reflected pulse. The long-time dynamics is dominated by resonant
transmission over length scales much larger than the localization length. The
corresponding distribution of the Wigner-Smith delay times is the Laguerre
ensemble of random-matrix theory. In the power spectrum the resonances show up
as a 1/t^2 tail after N^2 scattering times. In the distribution of single-mode
delay times the resonances introduce a dynamic coherent backscattering effect,
that provides a way to distinguish localization from absorption.

</DOC>
<DOC>
<DOCNO> 10780 </DOCNO>
Amplification of light and atoms in a Bose--Einstein condensate


  A Bose-Einstein condensate illuminated by a single off-resonant laser beam
(``dressed condensate'') shows a high gain for matter waves and light. We have
characterized the optical and atom-optical properties of the dressed condensate
by injecting light or atoms, illuminating the key role of long-lived matter
wave gratings produced by the condensate at rest and recoiling atoms. The
narrow bandwidth for optical gain gave rise to an extremely slow group velocity
of an amplified light pulse (1 m/s).

</DOC>
<DOC>
<DOCNO> 83463 </DOCNO>
Apache web server execution tracing using Third Eye


  Testing of modern software systems that integrate many components developed
by different teams is a difficult task. Third Eye is a framework for tracing
and validating software systems using application domain events. We use formal
descriptions of the constraints between events to identify violations in
execution traces. Third Eye is a flexible and modular framework that can be
used in different products. We present the validation of the Apache Web Server
access policy implementation. The results indicate that our tool is a helpful
addition to software development infrastructure.

</DOC>
<DOC>
<DOCNO> 68892 </DOCNO>
Magnetic Z(N) symmetry in hot QCD and the spatial Wilson loop


  We discuss the relation between the deconfining phase transition in gauge
theories and the realization of the magnetic Z(N) symmetry. At low temperature
the Z(N) symmetry is spontaneously broken while above the phase transition it
is restored. This is intimately related to the change of behaviour of the
spatial 't Hooft loop discussed in hep-ph/9909516. We also point out that the
realization of the magnetic symmetry has bearing on the behaviour of the
spatial Wilson loop. We give a physical argument to the effect that at zero
temperature the spatial Wilson loop must have perimeter law behaviour in the
symmetric phase but area law behaviour in the spontaneously broken phase. At
high temperature the argument does not hold and the restoration of magnetic
Z(N) is consistent with area law for the Wilson loop.

</DOC>
<DOC>
<DOCNO> 67891 </DOCNO>
Production of bound triplet $\mu^{+} \mu^{-}$ system in collisions of


  This paper deals with the production of orthodimuonium (OM) ($\mu^{+}
\mu^{-}$ atom in triplet state) in collisions of high-energy electrons with
nuclei or atoms. This reaction was previously studied by Holvik and Olsen
[Phys. Rev. D 35, 2124 (1987)] on the basis of a bremsstrahlung mechanism where
OM is produced by only one virtual photon. In the present paper we consider a
competing three-photon mechanism where the production of OM results from the
collision of a photon generated by the electron with two photons emitted by the
nucleus. We derive the corresponding spectrum and production rate of OM and
show that the three-photon mechanism is the dominant one for heavy atom target.

</DOC>
<DOC>
<DOCNO> 151613 </DOCNO>
Supergravity Solutions for Localised Brane Intersections


  We present a general method for constructing supergravity solutions for
intersecting branes. The solutions are written in terms of a single function,
which is the solution to a nonlinear differential equation. We illustrate this
procedure in detail for the case of M2-branes ending on M5-branes. We also
present supergravity solutions for strings ending on Dp-branes. Unlike previous
results in the literature, these branes are completely localized.

</DOC>
<DOC>
<DOCNO> 119645 </DOCNO>
Multiwavelength study of the nuclei of a volume-limited sample of


  We discuss ROSAT HRI X-ray observations of 33 very nearby galaxies, sensitive
to X-ray sources down to a luminosity of approximately 10^38 erg/s. The
galaxies are selected from a complete, volume limited sample of 46 galaxies
with d<7 Mpc for which we have extensive multi-wavelength data. For an almost
complete sub-sample with M_B<-14 (29/31 objects) we have HRI images. Contour
maps and source lists are presented within the central region of each galaxy,
together with nuclear upper limits where no nuclear source was detected.
Nuclear X-ray sources are found to be very common, occurring in ~35% of the
sample. Nuclear X-ray luminosity is statistically connected to host galaxy
luminosity - there is not a tight correlation, but the probability of a nuclear
source being detected increases strongly with galaxy luminosity and the
distribution of nuclear luminosities seems to show an upper envelope that is
roughly proportional to galaxy luminosity. While these sources do seem to be a
genuinely nuclear phenomenon rather than nuclear examples of the general X-ray
source population, it is far from obvious that they are miniature Seyfert
nuclei. The more luminous nuclei are very often spatially extended, and HII
region nuclei are detected just as often as LINERs. Finally, we also note the
presence of fairly common super-luminous X-ray sources in the off-nuclear
population - out of 29 galaxies we find 9 sources with a luminosity larger than
10^39 erg/s. These show no particular preference for more luminous galaxies.
One is already known to be a multiple SNR system, but most have no obvious
optical counterpart and their nature remains a mystery.

</DOC>
<DOC>
<DOCNO> 80981 </DOCNO>
Is the chiral U(1) theory trivial?


  The chiral U(1) theory differs from the corresponding vector theory by an
imaginary contribution to the effective action which amounts to a phase factor
in the partition function. The vector theory, i.e. QED, is known to be trivial
in the continuum limit. It is argued that the presence of the phase factor will
not alter this result and the chiral theory is non-interacting as well.

</DOC>
<DOC>
<DOCNO> 11737 </DOCNO>
An Empirical Pair-breaking Picture for the Non-linear Meissner Effect in


  A empirical model is proposed for the observed variation of the London
penetration depth of cuprate superconductors with applied magnetic field $H$
below the lower critical field H_c1. It is suggested that the Doppler shift of
the quasi-particle energies near the d-wave nodes could cause pair-breaking and
that this could be responsible for the non-linear Meissner effect (NLME)
investigated in recent experiments. This picture gives a somewhat better
description of the observed temperature and field dependencies than the
original theory proposed by Yip and Sauls. A calculation based on weak-coupling
BCS theory suggests that when there is a finite supercurrent, the state for
which pairs are broken in a small angular range around the nodes can have a
lower free energy than the d_x^2-y^2 state.

</DOC>
<DOC>
<DOCNO> 102246 </DOCNO>
Descendants of the Chiral Anomaly


  Chern-Simons terms are well-known descendants of chiral anomalies, when the
latter are presented as total derivatives. Here I explain that also
Chern-Simons terms, when defined on a 3-manifold, may be expressed as total
derivatives.

</DOC>
<DOC>
<DOCNO> 122419 </DOCNO>
SCUBA deep fields and source confusion


  Deep submillimetre(submm)-wave surveys made over the last three years using
the SCUBA camera at the 15-m James Clerk Maxwell Telescope (JCMT) have revealed
a new population of very luminous high-redshift galaxies. The properties of
this population, and their contribution to the intensity of the extragalactic
background radiation field are described briefly, especially in the context of
the SCUBA lens survey (carried out since 1997 by Ian Smail, Rob Ivison,
Jean-Paul Kneib and the author: a full description of the survey and references
to supporting work can be found in the recent catalogue paper). The potential
problems caused by source confusion in the large 15-arcsec SCUBA observing beam
for the identification and follow up of the results are discussed. The effects
of confusion are not important for the study of 850-micron SCUBA sources
brighter than about 2 mJy.

</DOC>
<DOC>
<DOCNO> 72178 </DOCNO>
The Monte Carlo Event Generator DPMJET-III


  A new version of the Monte Carlo event generator DPMJET is presented. It is a
code system based on the Dual Parton Model and unifies all features of the
DTUNUC-2, DPMJET-II and PHOJET 1.12 event generators. DPMJET-III allows the
simulation of hadron-hadron, hadron-nucleus, nucleus-nucleus, photon-hadron,
photon-photon and photon-nucleus interactions from a few GeV up to the highest
cosmic ray energies.

</DOC>
<DOC>
<DOCNO> 101816 </DOCNO>
Rigidity of geometrically finite hyperbolic cone-manifolds


  In a recent paper Hodgson and Kerckhoff prove a local rigidity theorem for
finite volume, three dimensional hyperbolic cone-manifolds. In this paper we
extend this result to geometrically finite cone-manifolds. Our methods also
give a new proof of a local version of the classical rigidity theorem for
geometrically finite hyperbolic 3-manifolds.

</DOC>
<DOC>
<DOCNO> 71830 </DOCNO>
Model for self-tuning the cosmological constant


  The vanishing cosmological constant in the four dimensional space-time is
obtained in a 5D Randall-Sundrum model with a brane (B1) located at $y=0$. The
matter fields can be located at the brane. For settling any vacuum energy
generated at the brane to zero, we need a three index antisymmetric tensor
field $A_{MNP}$ with a specific form for the Lagrangian. For the self-tuning
mechanism, the bulk cosmological constant should be negative.

</DOC>
<DOC>
<DOCNO> 116510 </DOCNO>
Contraction of a Bundle of Actin Filaments: 50 years after Szent-Gyorgyi


  Biological systems are among the most challenging subjects for theoretical
physicists, as well as experimentalists or simulationists. Physical principles
should have been both constraints and guide-lines for the evolution of living
systems over billions of years. One generally aims at clarifying what physical
principles, possibly new ones, are behind the phenomena of biological interest
and at understanding how they work within the entire biological world. In the
present talk we describe an example of such an effort.
  Since the discovery of `superprecipitation' by Szent-Gyorgyi's group in
1940's, it has been a long puzzle how an assemblage of actin filaments with
random orientation can contract in the presence of the two-headed myosin
molecules undergoing actin-activated ATP-hydrolysis reaction. It is widely
accepted that during the contraction the two-headed myosin mediates the
relative sliding of two actin filaments whose polarity directions are not
parallel but rather anti-parallel. But this fact solely does not account for
the shortening. We propose a dynamical model which, upon numerical simulation,
exhibits the shortening of an bundle of the actin filaments which are initially
dirstributed randomly both in space along a line and in polarity direction. In
the course of shortening several clusters of actins appears along the bundle.
The model also shows the sorting of the actin filaments according to their
polarity in the late stage. These findings are in accordance with the recent
experiment by Takiguchi.

</DOC>
<DOC>
<DOCNO> 121896 </DOCNO>
Clustering of Galaxies and Groups in the NOG Sample


  We use the two-point correlation function in redshift space, $\xi(s)$, to
study the clustering of the galaxies and groups of the Nearby Optical Galaxy
(NOG) Sample, which is a nearly all-sky, complete, magnitude-limited sample of
\~7000 bright and nearby optical galaxies. The correlation function of galaxies
is well-described by a power-law, $\xi(s)= (s/s_0)^{-\gamma}$, with
$\gamma\sim1.5$ and $s_0\sim 6.4 h^{-1}$ Mpc. We find evidence of morphological
segregation between early- and late-type galaxies, with a gradual decreasing of
the strength of clustering from the S0 to the late-type spirals, on
intermediate scales. Furthermore, luminous galaxies (with $M_B\leq -19.5 + 5
\log h$) are more clustered than dim galaxies. The groups show an excess of
clustering with respect to galaxies. Groups with greater velocity dispersions,
sizes, and masses are more clustered than those with lower values of these
quantities.

</DOC>
<DOC>
<DOCNO> 80679 </DOCNO>
The pion_0 to gamma gamma decay and the chiral anomaly in the


  We evaluate the pion_0 into two gammas decay amplitude by an effective action
derived from QCD in the quark composites approach, getting the standard value.
We also verify that our effective action correctly reproduces the chiral
anomaly.

</DOC>
<DOC>
<DOCNO> 117614 </DOCNO>
HEGRA Observations of Galactic Sources


  In this talk I will first give a summary of the observations of expected
Galactic TeV gamma-ray sources with the HEGRA CT-Sytem since the Kruger Park
Workshop in 1997. Then I will go into some detail regarding the observations of
Supernova Remnants (SNRs), especially those of Tycho's SNR and of Cas A. The
emphasis will not be on all aspects of these published data. I will rather
review the selection of these observational targets, and discuss some of the
physical implications of the results.

</DOC>
<DOC>
<DOCNO> 178631 </DOCNO>
Nuclear Shell Effects near the r-Process Path at N=82 in the


  Evolution of the shell structure of nuclei near the neutron drip line is
investigated in the Relativistic Hartree-Bogoliubov (RHB) theory. By
introducing the vector self-coupling of $\omega$ meson in the RHB theory, we
reproduce successfully the experimental data on the shell effects about the
waiting-point nucleus $^{80}$Zn. With this basis, it is shown that the shell
effects at N=82 in the inaccessible region of the r-process path remain strong.
In contrast, a quenching exhibited by the HFB+SkP approach is shown to be
incompatible with the available data. Consequently, the neutrino-driven
mechanism of the nucleosynthesis is supported.

</DOC>
<DOC>
<DOCNO> 83165 </DOCNO>
Axiomatic Synthesis of Computer Programs and Computability Theorems


  We introduce a set of eight universal Rules of Inference by which computer
programs with known properties (axioms) are transformed into new programs with
known properties (theorems). Axioms are presented to formalize a segment of
Number Theory, DataBase retrieval and Computability Theory. The resulting
Program Calculus is used to generate programs to (1) Determine if one number is
a factor of another. (2) List all employees who earn more than their manager.
(3) List the set of programs that halt no on themselves, thus proving that it
is recursively enumerable. The well-known fact that the set of programs that do
not halt yes on themselves is not recursively enumerable is formalized as a
program requirement that has no solution, an Incompleteness Axiom. Thus, any
axioms (programs) which could be used to generate this program are themselves
unattainable. Such proofs are presented to formally generate several additional
theorems, including (4) The halting problem is unsolvable.
  Open problems and future research is discussed, including the use of
temporary sort files, programs that calculate statistics (such as counts and
sums), the synthesis of programs to solve other well-known problems from Number
Theory, Logic, DataBase retrieval and Computability Theory, application to
Programming Language Semantics, and the formalization of incompleteness results
from Logic and the semantic paradoxes.

</DOC>
<DOC>
<DOCNO> 40024 </DOCNO>
Spectrum of neutrino masses and their nature in the light of present and


  The present experimental data on neutrino oscillations, neutrinoless double
beta decay and tritium beta decay are collected together and possible mass
ranges for Dirac and Majorana neutrinos are found. Four future experimental
situations are investigated: both decay experiments give only upper bounds, one
of them gives a positive result ($|< m_\nu > | \neq 0$ or $m_\beta \neq 0$), or
finally both effective neutrino masses are different from zero ($|< m_\nu > |
\neq 0$ and $m_\beta \neq 0$). Each scenario gives new information on neutrino
masses and nature but only the last has a chance to resolve the problem and
give some additional information on CP violation in the lepton sector.

</DOC>
<DOC>
<DOCNO> 11272 </DOCNO>
New physics of grain boundaries in bcc metals from the atomic level:


  We present a systematic trend study of the symmetric tilt grain boundaries
about the <110> axis in molybdenum. Our results show that multiple structural
phases, some incorporating vacancies, compete for the boundary ground state. We
find that at low external stress vacancies prefer to bind to the boundaries in
high concentrations, and moreover, that external stress drives structural phase
transitions which correspond to switching the boundaries on and off as
pipe-diffusion pathways for vacancies. Finally, we present physical arguments
which indicate these phenomena are likely to occur in the other bcc transition
metals as well.

</DOC>
<DOC>
<DOCNO> 11024 </DOCNO>
Short range ferromagnetism and spin glass state in


  Dynamic magnetic properties of $\mathrm{Y_{0.7}Ca_{0.3}MnO_{3}}$ are
reported. The system appears to attain local ferromagnetic order at
$T_{\mathrm{SRF}} \approx 70$ K. Below this temperature the low field
magnetization becomes history dependent, i.e. the zero field cooled (ZFC) and
field cooled (FC) magnetization deviate from each other and closely logarithmic
relaxation appears at our experimental time scales (0.3-$10^{4}$ sec). The zero
field cooled magnetization has a maximum at $T_{\mathrm{f}}\approx 30$ K,
whereas the field cooled magnetization continues to increase, although less
sharply, also below this temperature. Surprisingly, the dynamics of the system
shows non-equilibrium spin glass (SG) features not only below the maximum in
the ZFC magnetization, but also in the temperature region between this maximum
and $T_{\mathrm{SRF}}$. The aging and temperature cycling experiments show only
quantitative differences in the dynamic behavior above and below the maximum in
the ZFC-magnetization; similarly, memory effects are observed in both
temperature regions. We attribute the high temperature behavior to the
existence of clusters of short range ferromagnetic order below
$T_{\mathrm{SRF}}$; the configuration evolves into a conventional spin glass
state at temperatures below $T_{\mathrm{f}}$.

</DOC>
<DOC>
<DOCNO> 10131 </DOCNO>
Blind source separation in the presence of weak source


  We investigate the information processing of a linear mixture of independent
sources of different magnitudes. In particular we consider the case where a
number $m$ of the sources can be considered as ``strong'' as compared to the
other ones, the ``weak'' sources. We find that it is preferable to perform
blind source separation in the space spanned by the strong sources, and that
this can be easily done by first projecting the signal onto the $m$ largest
principal components. We illustrate the analytical results with numerical
simulations.

</DOC>
<DOC>
<DOCNO> 118530 </DOCNO>
Large Scale Structure in the weakly non-linear regime


  Is gravitational growth responsible for the observed large scale structure in
the universe? Do we need non-gaussian initial conditions or non-gravitational
physics to explain the large scale features traced by galaxy surveys? I will
briefly revise the basic ideas of non-linear perturbation theory (PT) as a tool
to understand structure formation, in particular through the study of higher
order statistics, like the skewness and the 3-point function. Contrary to what
happens with the second order statistics (the variance or power-spectrum), this
test of gravitational instability is independent of the overall amplitude of
fluctuations and of cosmic evolution, so that it does not require comparing the
clustering at different redshifts. Predictions from weakly non-linear PT have
been compared with observations to place constraints on our assumptions about
structure formation, the initial conditions and how galaxies trace the mass.

</DOC>
<DOC>
<DOCNO> 12500 </DOCNO>
Noise properties of the SET transistor in the co-tunneling regime


  Zero-frequency spectral densities of current noise, charge noise, and their
cross-correlation are calculated for the SET transistor in the co-tunneling
regime. The current noise has a form expected for the uncorrelated co-tunneling
events. Charge noise is created by the co-tunneling and also by the
second-order transitions in a single junction. Calculated spectral densities
determine transistor characteristics as quantum detector.

</DOC>
<DOC>
<DOCNO> 119198 </DOCNO>
Neutrino-antineutrino transition under CP-transformation and solar


  It is considered two neutrinos moving in the opposite directions. In one and
the same system of reference, one of the neutrinos is CP-transformed from
another neutrino, so one of two neutrinos transits into antineutrino. As a
consequence a half of neutrinos produced in the spherical shell transits into
antineutrinos. From this one observes a half of neutrino flux produced in the
sun that may provide a solution for the solar neutrino puzzle.

</DOC>
<DOC>
<DOCNO> 69914 </DOCNO>
Limitations in using luminosity distance to determine the equation of


  Supernova searches have been been suggested as a method for determining
precisely the current value and time variation of the equation of state, $w$,
of the dark energy component responsible for the accelerated expansion of the
Universe. We show that the method is fundamentally limited by the fact that
luminosity dista nce depends on $w$ through a multiple integral relation that
smears out information about $w$ and its time variatio n. The effect degrades
the resolution of $w$ that can be obtained from current d ata.

</DOC>
<DOC>
<DOCNO> 99962 </DOCNO>
Classification of Gauge Orbit Types for SU(n)-Gauge Theories


  A method for determining the orbit types of the action of the group of gauge
transformations on the space of connections for gauge theories with gauge group
SU(n) in space-time dimension d<=4 is presented. The method is based on the
1:1-correspondence between orbit types and holonomy-induced Howe subbundles of
the underlying principal SU(n)-bundle. It is shown that the orbit types are
labelled by certain cohomology elements of space-time satisfying two relations.
Thus, for every principal SU(n)-bundle the corresponding stratification of the
gauge orbit space can be determined explicitly. As an application, a criterion
characterizing kinematical nodes for physical states in 2+1-dimensional
Chern-Simons theory proposed by Asorey et al. is discussed.

</DOC>
<DOC>
<DOCNO> 119941 </DOCNO>
Chemical Abundances and Ionizing Clusters of HII Regions in the LINER


  We present long-slit observations in the optical and near infrared of eight
HII regions in the spiral galaxy NGC 4258. Six of the observed regions are
located in the SE inner spiral arms and the other two are isolated in the
northern outer arms. A detailed analysis of the physical conditions of the gas
has been performed. For two of the regions, an electron temperature has been
derived from the [SIII] 6312 A line. For the rest, an empirical calibration
based on the red and near infrared sulphur lines has been used. The oxygen
abundances derived by both methods are found to be significantly lower (by a
factor of two) than previously derived by using empirical calibrations based on
the optical oxygen lines. In the brightest region, 74C, the observation of a
prominent feature due to Wolf-Rayet stars provides an excellent constraint over
some properties of the ionizing clusters. In the light of the current
evolutionary synthesis models, no consistent solution is found to explain at
the same time both the WR feature characteristics and the emission line
spectrum of this region. In principle, the presence of WR stars could lead to
large temperature fluctuations and also to a hardening of the ionizing
radiation. None of these effects are found in region 74C for which the electron
temperatures found from the [SIII] 6312A and the Paschen discontinuity at 8200A
are equal within the errors and the effective temperature of the ionizing
radiation is estimated at around 35,300K. Both more observations of confirmed
high metallicity regions and a finer metallicity grid for the evolutionary
synthesis models are needed in order to understand the ionizing populations of
HII regions.

</DOC>
<DOC>
<DOCNO> 8418 </DOCNO>
Interplay of Disorder and Correlations


  I address here the question of the mutual interplay of strong correlations
and disorder in the system. I consider random version of the Hubbard model.
Diagonal randomness is introduced {\it via} random on-site energies and treated
by the coherent potential approximation. Strong, short ranged, electron -
electron interactions are described by the slave boson technique and found to
induce additional disorder in the system. As an example I calculate the density
of states of the random interacting binary alloy and compare it with that for
non-interacting system.

</DOC>
<DOC>
<DOCNO> 69156 </DOCNO>
Two-particle correlation from a relativistic fluid with a first order


  We numerically calculate two-particle correlation functions of CERN-SPS 158
 A GeV Pb+Pb central collisions based on a (3+1)-dimensional relativistic
hydrodynamics with a first order phase transition. We analyze the pair momentum
dependence of pion source sizes extracted from the
 Yano-Koonin-Podgoretski\u{\i} (YKP) parametrization which is expected to give
the source sizes directly. We find that, even in the case of the first order
phase transition, the collective expansion and surface dominant freeze-out of
the fluid naturally lead to the opaque source for which the interpretation of
the temporal source parameter as the emission duration breaks down.

</DOC>
<DOC>
<DOCNO> 80975 </DOCNO>
Computer Simulations of 3d Lorentzian Quantum Gravity


  We investigate the phase diagram of non-perturbative three-dimensional
Lorentzian quantum gravity with the help of Monte Carlo simulations. The system
has a first-order phase transition at a critical value $k_0^c$ of the bare
inverse gravitational coupling constant $k_0$. For $k_0 > k_0^c$ the system
reduces to a product of uncorrelated Euclidean 2d gravity models and has no
intrinsic interest as a model of 3d gravity. For $k_0 < k_0^c$, extended
three-dimensional geometries dominate the functional integral despite the fact
that we perform a sum over geometries and no particular background is
distinguished at the outset. Furthermore, all systems with $k_0 < k_0^c$ have
the same continuum limit. A different choice of $k_0$ corresponds merely to a
redefinition of the overall length scale.

</DOC>
<DOC>
<DOCNO> 83460 </DOCNO>
A Moment of Perfect Clarity II: Consequences of Sparse Sets Hard for NP


  This paper discusses advances, due to the work of Cai, Naik, and Sivakumar
and Glasser, in the complexity class collapses that follow if NP has sparse
hard sets under reductions weaker than (full) truth-table reductions.

</DOC>
<DOC>
<DOCNO> 102672 </DOCNO>
Construction of Monodromy Matrix in the F- basis and Scalar products in


  We present in a simple terms the theory of the factorizing operator
introduced recently by Maillet and Sanches de Santos for the spin - 1/2 chains.
We obtain the explicit expressions for the matrix elements of the factorizing
operator in terms of the elements of the Monodromy matrix. We use this results
to derive the expression for the general scalar product for the quantum spin
chain. We comment on the previous determination of the scalar product of Bethe
eigenstate with an arbitrary dual state. We also establish the direct
correspondence between the calculations of scalar products in the F- basis and
the usual basis.

</DOC>
<DOC>
<DOCNO> 123231 </DOCNO>
On the Influence of Magnetic Fields on the Structure of Protostellar


  We here present the first results of fully three-dimensional (3-D) MHD
simulations of radiative cooling pulsed (time-variable) jets for a set of
parameters which are suitable for protostellar outflows. Considering different
initial magnetic field topologies in approximate $equipartition$ with the
thermal gas, i.e., (i) a longitudinal, and (ii) a helical field, both of which
permeating the jet and the ambient medium; and (iii) a purely toroidal field
permeating only the jet, we find that the overall morphology of the pulsed jet
is not very much affected by the presence of the different magnetic field
geometries in comparison to a nonmagnetic calculation. Instead, the magnetic
fields tend to affect essentially the detailed structure and emission
properties behind the shocks at the head and at the pulse-induced internal
knots, particularly for the helical and toroidal geometries. In these cases, we
find, for example, that the $H_\alpha$ emissivity behind the internal knots can
be about three to four times larger than that of the purely hydrodynamical jet.
We also find that some features, like the nose cones that often develop at the
jet head in 2-D calculations involving toroidal magnetic fields, are smoothed
out or absent in the 3-D calculations.

</DOC>
<DOC>
<DOCNO> 69559 </DOCNO>
Black Holes and Spacetime Physics in String/M Theory


  In addition to briefly reviewing recent progress in studying black hole
physics in string/M theory, we describe several robust features pertaining to
spacetime physics that one can glean by studying quantum physics of black
holes. In particular, we review 't Hooft's S-matrix ansatz which results in a
noncommutative horizon. A recent construction of fuzzy AdS2 is emphasized, this
is a nice toy model for fuzzy black hole horizon. We demonstrate that this
model captures some nonperturbative features of quantum gravity.

</DOC>
<DOC>
<DOCNO> 117080 </DOCNO>
From Superluminal Velocity To Time Machines?


  Various experiments have shown superluminal group and signal velocities
recently. Experiments were essentials carried out with microwave tunnelling,
with frustrated total internal reflection, and with gain-assisted anomalous
dispersion. According to text books a superluminal signal velocity violates
Einstein causality implying that cause and effect can be changed and time
machines known from science fiction could be constructed. This naive analysis,
however, assumes a signal to be a point in the time dimension neglecting its
finite duration. A signal is not presented by a point nor by its front, but by
its total length. On the other hand a signal energy is finite thus its
frequency band is limited, the latter is a fundamental physical property in
consequence of field quantization with quantum $h \nu$. All superluminal
experiments have been carried out with rather narrow frequency bands. The
narrow band width is a condition sine qua non to avoid pulse reshaping of the
signal due to the dispersion relation of the tunnelling barrier or of the
excited gas, respectively. In consequence of the narrow frequency band width
the time duration of the signal is long so that causality is preserved.
However, superluminal signal velocity shortens the otherwise luminal time span
between cause and effect.

</DOC>
<DOC>
<DOCNO> 70257 </DOCNO>
One-loop Reggeon-Reggeon-gluon vertex at arbitrary space-time dimension


  In order to check the compatibility of the gluon Reggeization in QCD with the
$s$-channel unitarity, the one-loop correction to the Reggeon-Reggeon-gluon
vertex must be known at arbitrary space-time dimension $D$. We obtain this
correction from the gluon production amplitude in the multi-Regge kinematics
and present an explicit expression for it in terms of a few integrals over the
transverse momenta of virtual particles. The one-gluon contribution to the
non-forward BFKL kernel at arbitrary $D$ is also obtained.

</DOC>
<DOC>
<DOCNO> 40488 </DOCNO>
Report of the Working Group on Precision Measurements


  In the first part of this report, we discuss the prospects for measuring the
W mass and width in Run II. The basic techniques used to measure M_W are
described and the statistical, theoretical and detector-related uncertainties
are discussed in detail. Alternative methods of measuring the W mass at the
Tevatron and the prospects for M_W measurements at other colliders are also
described. In the second part, we discuss the measurement of the forward
backward asymmetry in Drell Yan production in Run II which can be used to
determine the effective weak mixing angle. Estimates of the statistical and
systematic uncertainties in Run II are given. The third part summarizes the
features of the FORTRAN package GAPP which performs a fit to the electroweak
observables and extracts the probability distribution function of the Higgs
boson mass.

</DOC>
<DOC>
<DOCNO> 120118 </DOCNO>
Radio Halos and Relics in Clusters of Galaxies and Detection Statistics


  New sensitive VLA observations confirm the existence of halo and relic
sources in 6 Abell clusters where a diffuse emission was found in the NVSS. We
find evidence that the frequency of clusters with halos and relics is larger in
clusters with high X-ray luminosity. The evidence that the occurrence of a halo
source is larger at high redshifts is marginal.

</DOC>
<DOC>
<DOCNO> 7738 </DOCNO>
Lattice parameters from direct-space images at two tilts


  Lattices in three dimensions are oft studied from the ``reciprocal space''
perspective of diffraction. Today, the full lattice of a crystal can often be
inferred from direct-space information about three sets of non-parallel lattice
planes. Such data can come from electron-phase or Z contrast images taken at
two tilts, provided that one image shows two non-parallel lattice
periodicities, and the other shows a periodicity not coplanar with the first
two. We outline here protocols for measuring the 3D parameters of cubic lattice
types in this way. For randomly-oriented nanocrystals with cell side greater
than twice the continuous transfer limit, orthogonal +/-15 deg and +/-10 deg
tilt ranges might allow one to measure 3D parameters of all such lattice types
in a specimen from only two well-chosen images. The strategy is illustrated by
measuring the lattice parameters of a 10 nm WC_{1-x} crystal in a
plasma-enhanced chemical-vapor deposited thin film.

</DOC>
<DOC>
<DOCNO> 39787 </DOCNO>
Implications of Quark-Lepton Symmetry for Neutrino Masses and


  We identify a plausible scenario based on quark-lepton symmetry which
correlates long baseline oscillations with maximal mixing to sterile neutrinos.
The implication for the Sudbury Neutrino Observatory (SNO) is that the neutral
current signal will be found to suffer the same suppression from the Standard
Solar Model prediction as obtains for the charged current signal. Flavor mixing
among active neutrinos is expected to occur on shorter baselines with smaller
mixing amplitudes.

</DOC>
<DOC>
<DOCNO> 40118 </DOCNO>
Observation of New States Decaying into Lambda_c^+pi-pi+


  Using 13.7 fb^{-1} of data recorded by the CLEO detector at CESR, we
investigate the spectrum of charmed baryons which decay into Lambda_c^+ pi^-
pi^+ and are more massive than the Lambda_{c1} baryons. We find evidence for
two new states: one is broad and has an invariant mass roughly 480 MeV above
that of the Lambda_c^+; the other is narrow with an invariant mass of 596 +- 1
+- 2 MeV above the Lambda_c^+ mass. These results are preliminary.

</DOC>
<DOC>
<DOCNO> 150418 </DOCNO>
Hopf instantons and the Liouville equation in target space


  We generalise recent results on Hopf instantons in a Chern--Simons and
Fermion theory in a fixed background magnetic field. We find that these
instanton solutions have to obey the Liouville equation in target space. As a
consequence, these solutions are given by a class of Hopf maps that consist of
the composition of the standard Hopf map with an arbitrary rational map.

</DOC>
<DOC>
<DOCNO> 120470 </DOCNO>
Non-LTE effects in neutron star atmospheres


  We present the first non-LTE model atmospheres for neutron stars (NS). We
study their structure and NLTE effects on the emergent thermal radiation of old
isolated NS.

</DOC>
<DOC>
<DOCNO> 119557 </DOCNO>
Dwarf satellite galaxies in the modified dynamics


  In the modified dynamics (MOND) the inner workings of dwarf satellites can be
greatly affected by their mother galaxy-over and beyond its tidal effects.
Because of MOND's nonlinearity a system's internal dynamics can be altered by
an external field in which it is immersed (even when this field, by itself, is
constant in space). As a result, the size and velocity dispersion of the
satellite vary as the external field varies along its orbit. A notable outcome
of this is a substantial increase in the dwarf's vulnerability to eventual
tidal disruption-rather higher than Newtonian dynamics (with a dark-matter
halo) would lead us to expect for a satellite with given observed parameters.

</DOC>
<DOC>
<DOCNO> 120068 </DOCNO>
Probing the Interstellar Medium in Early type galaxies with ISO


  Four IRAS-detected early type galaxies were observed with ISO. With the
exception of the 15 micron image of NGC1052, the mid-IR emission from NGC1052,
NGC1155, NGC5866 and NGC6958 at 4.5, 7 and 15 microns show extended emission.
Mid-IR emission from NGC1052, NGC1155, and NGC6958 follows a de Vaucouleurs
profile. The ratio of 15/7 micron flux decreases with radius in these galaxies,
approaching the values empirically observed for purely stellar systems. In
NGC5866, the 7 and 15 micron emission is concentrated in the edge-on dust lane.
All the galaxies are detected in the [CII] line, and the S0s NGC1155 and
NGC5866 are detected in the [OI] line as well. The ISO-LWS observations of the
[CII] line are more sensitive measures of cool, neutral ISM than HI and CO by
about a factor of 10-100. Three of four early type galaxies, namely NGC1052,
NGC6958 and NGC5866, have low ratio FIR/Blue and show a lower [CII]/FIR, which
is due to a softer radiation field from old stellar populations. The low
[CII]/CO ratio in NGC5866 ([CII]/CO(1-0) < 570) confirms this scenario. We
estimate the UV radiation expected from the old stellar populations in these
galaxies and compare it to that needed to heat the gas to account for the
cooling observed [CII] and [OI] lines. In three out of four galaxies, NGC1052,
NGC5866 and NGC6958, the predicted UV radiation falls short by a factor of 2-3.
In view of the observed intrinsic scatter in the "UV-upturn" in elliptical
galaxies and its great sensitivity to age and metallicity effects, this is not
significant. However, the much larger difference (about a factor of 20) between
the UV radiation from old stars and that needed to produce the FIR lines for
NGC 1155 is strong evidence for the presence of young stars, in NGC1155.

</DOC>
<DOC>
<DOCNO> 71335 </DOCNO>
Deep inelastic scattering at low x: Generalized vector dominance and the


  We summarize recent work on low-x deep inelastic scattering. The generalized
vector dominance/color-dipole picture (GVD/CDP) implies a scaling behavior for
$\sigma_{\gamma^* p} (W^2, Q^2)\cong \sigma_{\gamma^* p}(\eta)$, with $\eta =
(Q^2 + m^2_0)/\Lambda^2 (W^2)$ and yields an excellent representation of the
experimental results on $\sigma_{\gamma^* p}(\eta)$.

</DOC>
<DOC>
<DOCNO> 120862 </DOCNO>
Galaxy Groups at Intermediate Redshift


  Galaxy groups likely to be virialized are identified within the CNOC2
intermediate redshift galaxy survey using an iterative method. The
number-velocity dispersion relation is in agreement with the low-mass
extrapolation of the cluster normalized Press-Schechter function. The two-point
group-group correlation function has r_0=6.8+/- 0.3 Mpc, which is larger than
the correlations of individual galaxies at the level predicted from n-body
calibrated halo clustering.
 The groups are stacked in velocity and position to create a sample large
enough for measurement of a density and velocity dispersion profile. The
stacked mean galaxy density profile falls nearly as a power law with r^{-2.5}
and has no well-defined core. The projected velocity dispersion is examined for
a variety of samples with different methods and found to be either flat or
slowly rising outwards. The combination of a steeper-than-isothermal density
profile and the outward rising velocity dispersion implies that the
mass-to-light ratio of groups rises with radius. The M/L can be kept nearly
constant if the galaxy orbits are nearly circular, although such strong
tangential anisotropy is not supported by other evidence. The segregation of
mass and light is not dependent on galaxy luminosity but is far more prominent
in the red galaxies than the blue. The M/L gradient could arise from orbital
``sloshing'' of the galaxies in the group halos, dynamical friction acting on
the galaxies in a background of ``classical'' collisionless dark matter, or,
more speculatively, the dark matter may have a true core.

</DOC>
<DOC>
<DOCNO> 119710 </DOCNO>
Deep far infrared ISOPHOT survey in "Selected Area 57", I. Observations


  We present here the results of a deep survey in a 0.4 sq.deg. blank field in
Selected Area 57 conducted with the ISOPHOT instrument aboard ESAs Infrared
Space Observatory (ISO) at both 60 um and 90 um. The resulting sky maps have a
spatial resolution of 15 x 23 sq.arcsec. per pixel which is much higher than
the 90 x 90 sq.arcsec. pixels of the IRAS All Sky Survey. We describe the main
instrumental effects encountered in our data, outline our data reduction and
analysis scheme and present astrometry and photometry of the detected point
sources. With a formal signal to noise ratio of 6.75 we have source detection
limits of 90 mJy at 60 um and 50 mJy at 90 um. To these limits we find
cumulated number densities of 5+-3.5 per sq.deg. at 60 um and 14.8+-5.0 per
sq.deg.at 90 um. These number densities of sources are found to be lower than
previously reported results from ISO but the data do not allow us to
discriminate between no-evolution scenarios and various evolutionary models.

</DOC>
<DOC>
<DOCNO> 170522 </DOCNO>
Spin squeezing of mixed systems


  The notion of spin squeezing has been discussed in this paper using the
density matrix formalism. Extending the definition of squeezing for pure states
given by Kitagawa and Ueda in an appropriate manner and employing the spherical
tensor representation, we show that mixed spin states which are non-oriented
and possess vector polarization indeed exhibit squeezing. We construct a mixed
state of a spin 1 system using two spin 1/2 states and study its squeezing
behaviour as a function of the individual polarizations of the two spinors.

</DOC>
<DOC>
<DOCNO> 10223 </DOCNO>
Brownian Motion on a Sphere: Distribution of Solid Angles


  We study the diffusion of Brownian particles on the surface of a sphere and
compute the distribution of solid angles enclosed by the diffusing particles.
This function describes the distribution of geometric phases in two state
quantum systems (or polarised light) undergoing random evolution. Our results
are also relevant to recent experiments which observe the Brownian motion of
molecules on curved surfaces like micelles and biological membranes. Our
theoretical analysis agrees well with the results of computer experiments.

</DOC>
<DOC>
<DOCNO> 151106 </DOCNO>
The Renormalized Thermal Mass with Non-Zero Charge Density


  The linear $\delta$ expansion is used to obtain corrections up to
O$(\delta^2)$ to the self-energy for a complex scalar field theory with a
$\lambda (\phi^{\star}\phi)^2$ interaction at high temperature and non-zero
charge density. The calculation is done in the imaginary-time formalism via the
Hamiltonian form of the path integral. Nonperturbative results are generated by
a systematic order by order variational procedure and the dependence of the
critical temperature on the chemical potential $\mu$ is obtained.

</DOC>
<DOC>
<DOCNO> 121864 </DOCNO>
Discovery of short-period binary millisecond pulsars in four globular


  We report the discovery using the Parkes radio telescope of binary
millisecond pulsars in four clusters for which no associated pulsars were
previously known. The four pulsars have pulse periods lying between 3 and 6 ms.
All are in circular orbits with low-mass companions and have orbital periods of
a few days or less. One is in a 1.7-hour orbit with a companion of planetary
mass. Another is eclipsed by a wind from its companion for 40% of the binary
period despite being in a relatively wide orbit. These discoveries result from
the use of improved technologies and prove that many millisecond pulsars remain
to be found in globular clusters.

</DOC>
<DOC>
<DOCNO> 11379 </DOCNO>
Dissipative dynamics of vortex arrays in anisotropic traps


  We discuss the dissipative dynamics of vortex arrays in trapped
Bose-condensed gases and analyze the lifetime of the vortices as a function of
trap anisotropy and the temperature. In particular, we distinguish the two
regimes of the dissipative dynamics, depending on the relative strength of the
mutual friction between the vortices and the thermal component, and the
friction of the thermal particles on the trap anisotropy. We study the effects
of heating of the thermal cloud by the escaping vortices on the dynamics of the
system.

</DOC>
<DOC>
<DOCNO> 69564 </DOCNO>
Deconfining by Winding: The Magnetic Monopole Vacua at High Temperatures


  Characterizing the vacuum of a thermalized SU(3) Yang-Mills theory in the
dual Ginzburg-Landau description, the possibility of topologically nontrivial,
classical monopole fields in the deconfining phase is explored. These fields
are assumed to be Bogomoln'yi-Prasad-Sommerfield (BPS) saturated solutions
along the compact, euclidean time dimension. A corresponding, gauge invariant
monopole interaction is constructed. The model passes first tests. In
particular, a reasonable value for the critical temperature is obtained, and
the partial persistence of nonperturbative features in the deconfining phase of
SU(3) Yang-Mills theory, as it is measured on the lattice, follows naturally.

</DOC>
<DOC>
<DOCNO> 120962 </DOCNO>
Biased Galaxy Formation And Measurements Of Beta


  Measurements of the cosmological density parameter Omega using techniques
that exploit the gravity-induced motions of galaxies constrain, in linear
perturbation theory, the degenerate parameter combination beta = Omega^{0.6}/b,
where the linear bias parameter b is the ratio of the fluctuation amplitudes of
the galaxy and mass distributions. However, the relation between the galaxy and
mass density fields depends on the complex physics of galaxy formation, and it
can in general be non-linear, stochastic, and perhaps non-local. The
one-parameter linear bias model is almost certainly oversimplified, which leads
to the obvious question: What is the quantity beta that is actually measured by
different techniques? To address this question, we estimate beta from galaxy
distributions that are constructed by applying a variety of locally biased
galaxy formation models to cosmological N-body simulations. We compare the
values of beta estimated using three different techniques: a density-density
comparison similar to the POTENT analysis, a velocity-velocity comparison
similar to the VELMOD analysis, and an anisotropy analysis of the
redshift-space power spectrum. In most cases, we find that beta estimated using
all three methods is similar to the asymptotic value of
Omega^{0.6}/b_{sigma}(R) at large R, where b_{sigma}(R) is the ratio of rms
galaxy fluctuations to rms mass fluctuations on scale R. Thus, something close
to the conventional interpretation of beta continues to hold even for complex
bias models. Moreover, we find that beta estimates made using these three
methods should, in principle, agree with each other. It is thus unlikely that
non-linear or scale-dependent bias is responsible for the discrepancies that
exist among current measurements of beta from different techniques.

</DOC>
<DOC>
<DOCNO> 85057 </DOCNO>
Loop Quantum Cosmology IV: Discrete Time Evolution


  Using general features of recent quantizations of the Hamiltonian constraint
in loop quantum gravity and loop quantum cosmology, a dynamical interpretation
of the constraint equation as evolution equation is presented. This involves a
transformation from the connection to a dreibein representation and the
selection of an internal time variable. Due to the discrete nature of
geometrical quantities in loop quantum gravity also time turns out to be
discrete leading to a difference rather than differential evolution equation.
Furthermore, evolving observables are discussed in this framework which enables
an investigation of physical spectra of geometrical quantities. In particular,
the physical volume spectrum is proven to equal the discrete kinematical volume
spectrum in loop quantum cosmology.

</DOC>
<DOC>
<DOCNO> 8182 </DOCNO>
Number of distinct sites visited by N random walkers on a Euclidean


  The evaluation of the average number S_N(t) of distinct sites visited up to
time t by N independent random walkers all starting from the same origin on an
Euclidean lattice is addressed. We find that, for the nontrivial time regime
and for large N, S_N(t) \approx \hat S_N(t) (1-\Delta), where \hat S_N(t) is
the volume of a hypersphere of radius (4Dt \ln N)^{1/2},
\Delta={1/2}\sum_{n=1}^\infty \ln^{-n} N \sum_{m=0}^n s_m^{(n)} \ln^{m} \ln N,
d is the dimension of the lattice, and the coefficients s_m^{(n)} depend on the
dimension and time. The first three terms of these series are calculated
explicitly and the resulting expressions are compared with other approximations
and with simulation results for dimensions 1, 2, and 3. Some implications of
these results on the geometry of the set of visited sites are discussed.

</DOC>
<DOC>
<DOCNO> 69377 </DOCNO>
Large momentum transfer electroproduction of mesons


  Assuming the proton's light-cone wave function to be dominated by small
parton virtualities and small intrinsic transverse momenta, we show that the
electroproduction amplitudes at large momentum transfer factorize into
parton-level subprocess amplitudes and form factors representing 1/x-moments of
skewed parton distributions. On the basis of a wave function overlap model for
the form factors we present detailed predictions for the electroproduction
cross sections. We also comment on large momentum transfer photoproduction.

</DOC>
<DOC>
<DOCNO> 152333 </DOCNO>
Light-cone Form of Field Dynamics in AdS space-time


  Light-cone approach to field dynamics in AdS space-time is discussed.

</DOC>
<DOC>
<DOCNO> 8977 </DOCNO>
QCD In Extreme Conditions


  Recently we have made considerable progress in our understanding of the
behavior of QCD in extreme conditions of high temperature or large baryon
number density. Among the highlights are the prediction of a well-characterized
true critical point, and the discovery that the ground state of three-flavor
QCD at asymptotically high densities exhibits color-flavor locking. The
critical point occurs at the unique temperature and density where a sharp
distinction between an ionized plasma of quarks and gluons and the hadronic
phase first appears. It appears to be accessible both to numerical and to
laboratory experiments. Color-flavor locking provides a calculable,
weak-coupling realization of confinement and chiral symmetry breaking. It also
provides a microscopic realization of Han-Nambu charge assignments for quark
quasiparticles, and of Yang-Mills theory for the physical vector mesons. Here I
provide a self-contained introduction to these developments.

</DOC>
<DOC>
<DOCNO> 71602 </DOCNO>
On Superfluid Phases of Cold Deconfined QCD Matter at Moderate Baryon


  We present an overview of the arguments which lead to the picture that at low
temperatures the QCD matter not far above a critical confinement-deconfinement
density exists in one of several distinct superfluid phases exhibiting the
quantum behavior on macroscopic scales.

</DOC>
<DOC>
<DOCNO> 11932 </DOCNO>
Microscopic Theory of Protein Folding Rates.II: Local Reaction


  The motion involved in barrier crossing for protein folding are investigated
in terms of the chain dynamics of the polymer backbone, completing the
microscopic description of protein folding presented in the previous paper.
Local reaction coordinates are identified as collective growth modes of the
unstable fluctuations about the saddle-points in the free energy surface. The
description of the chain dynamics incorporates internal friction (independent
of the solvent viscosity) arising from the elementary isomerizations of the
backbone dihedral angles. We find that the folding rate depends linearly on the
solvent friction for high viscosity, but saturates at low viscosity because of
internal friction. For $\lambda$-repressor, the calculated folding rate
prefactor, along with the free energy barrier from the variational theory,
gives a folding rate that agrees well with the experimentally determined rate
under highly stabilizing conditions, but the theory predicts too large a
folding rate at the transition midpoint. This discrepancy obtained using a
fairly complete quantitative theory inspires a new set of questions about chain
dynamics, specifically detailed motions in individual contact formation.

</DOC>
<DOC>
<DOCNO> 152275 </DOCNO>
Finite-Temperature Casimir Effect on the Radius Stabilization of


  The one-loop correction to the spectrum of Kaluza-Klein system for the
$\phi^3$ model on $R^{1,d}\times (T_\theta^2)^L$ is evaluated in the high
temperature limit, where the $1+d$ dimensions are the ordinary flat Minkowski
spacetimes and the $L$ extra two-dimensional tori are chosen to be the
noncommutative torus with noncommutativity $\theta$. The corrections to the
Kaluza-Klein mass formula are evaluated and used to compute the Casimir energy
with the help of the Schwinger perturbative formula in the zeta-function
regularization method. The results show that the one-loop Casimir energy is
independent of the radius of torus if L=1. However, when $L>1$ the Casimir
energy could give repulsive force to stabilize the extra noncommutative torus
if $d-L$ is a non-negative even integral. This therefore suggests a possible
stabilization mechanism of extra radius in high temperature, when the extra
spaces are noncommutative.

</DOC>
<DOC>
<DOCNO> 40622 </DOCNO>
Measurement of sin2phi_1 at Belle


  With 6.2 fb^-1 of data collected on the Upsilon(4S), Belle reports its first
measurement of sin 2\phi_1 = 0.45^{+0.43}_{-0.44}(stat)^{+0.07}_{-0.09}(sys).
The result was obtained by fitting the proper time distribution of flavor
tagged and fully reconstructed neutral B mesons decays to five different
charmonia plus a Kshort or Klong channels. In this paper the analysis and
results will be described briefly.

</DOC>
<DOC>
<DOCNO> 170797 </DOCNO>
Strong Converse for Identification via Quantum Channels


  In this paper we present a simple proof of the strong converse for
identification via discrete memoryless quantum channels, based on a novel
covering lemma. The new method is a generalization to quantum communication
channels of Ahlswede's recently discovered appoach to classical channels. It
involves a development of explicit large deviation estimates to the case of
random variables taking values in selfadjoint operators on a Hilbert space.
This theory is presented separately in an appendix, and we illustrate it by
showing its application to quantum generalizations of classical hypergraph
covering problems.

</DOC>
<DOC>
<DOCNO> 122575 </DOCNO>
CORMASS: A Compact and Efficient NIR Spectrograph for Studying Low-Mass


  CorMASS (Cornell Massachusetts Slit Spectrograph) is a compact,
low-resolution (R=300), double-pass prism cross-dispersed near-infrared (NIR)
spectrograph in operation on the Palomar Observatory 60-inch telescope. Its
2-dimensional spectral format provides simultaneous coverage from lambda ~ 0.75
microns to lambda ~ 2.5 microns (z'JHK bands). A remotely operated cold flip
mirror permits its NICMOS3 detector to function as a K_s slit viewer to assist
object placement into the 2 arcsec x 15 arcsec slit. CorMASS was primarily
designed for the rapid spectral classification of low-mass stellar and
sub-stellar objects identified by the Two-Micron All Sky Survey (2MASS).
CorMASS' efficiency and resolution also make it a versatile instrument for the
spectral observation and classification of many other types of bright objects
(K<14) including quasars, novae, and emission line objects.

</DOC>
<DOC>
<DOCNO> 69435 </DOCNO>
Theoretical status of epsilon'/epsilon


  We review the theory of epsilon'/epsilon and present an updated
phenomenological analysis using hadronic matrix elements from lattice QCD. The
present status of the computation of epsilon'/epsilon, considering various
approaches to the matrix-element evaluation, is critically discussed.

</DOC>
<DOC>
<DOCNO> 9673 </DOCNO>
Periodic Ground States in the Neutral Falicov-Kimball Model in Two


  We consider the Falicov-Kimball model in two dimensions in the neutral case,
i.e, the number of mobile electrons is equal to the number of ions. For
rational densities between 1/3 and 2/5 we prove that the ground state is
periodic if the strength of the attraction between the ions and electrons is
large enough. The periodic ground state is given by taking the one dimensional
periodic ground state found by Lemberger and then extending it into two
dimensions in such a way that the configuration is constant along lines at a 45
degree angle to the lattice directions.

</DOC>
<DOC>
<DOCNO> 118024 </DOCNO>
Some Aspects of Inverse Compton Emission from 3K Background Photons


  We review the history and a few features of IC/3K emission. We discuss
observing strategies, the physical parameters which can be derived directly or
indirectly from successful detections, and the disparities between magnetic
field strength estimates found by different methods.

</DOC>
<DOC>
<DOCNO> 100893 </DOCNO>
The modelling and analysis of fractional-order control systems in


  This paper deals with fractional-order controlled systems and
fractional-order controllers in the discrete domain. The mathematical
description by the fractional difference equations and properties of these
systems are presented. A practical example for modelling the fractional-order
control loop is shown and obtained results are discussed in conclusion.

</DOC>
<DOC>
<DOCNO> 67776 </DOCNO>
Asymptotic Gluon Shadowing


  We examine the low Bjorken $x$ gluon distribution in nuclei in the asymptotic
region.

</DOC>
<DOC>
<DOCNO> 118266 </DOCNO>
Star Formation and Tidal Encounters with the Low Surface Brightness


  We present VLA H I observations of the low surface brightness galaxy UGC
12695 and its two companions, UGC 12687 and a newly discovered dwarf galaxy
2333+1234. UGC 12695 shows solid body rotation but has a very lopsided
morphology of the H I disk, with the majority of the H I lying in the southern
arm of the galaxy. The H I column density distribution of this very blue, LSB
galaxy coincides in detail with its light distribution. Comparing the H I
column density of UGC 12695 with the empirical (but not well understood) value
of Sigma_c = 10E21 atoms/cm^2 found in, i.e., Skillman's 1986 paper shows the
star formation to be a local affair, occurring only in those regions where the
column density is above this star formation threshold. The low surface
brightness nature of this galaxy could thus be attributed to an insufficient
gas surface density, inhibiting star formation on a more global scale.
Significantly, though, the Toomre criterion places a much lower critical
density on the galaxy (+/-10E20 atoms/cm^2), which is shown by the galaxy's low
SFR to not be applicable.
  Within a projected distance of 300kpc/30kms of UGC 12695 lie two companion
galaxies - UGC 12687, a high surface brightness barred spiral galaxy, and
2333+1234, a dwarf galaxy discovered during this investigation. The close
proximity of the three galaxies, combined with UGC 12695's extremely blue color
and regions of localized starburst and UGC 12687's UV excess bring to mind
mutually induced star formation through tidal activity.

</DOC>
<DOC>
<DOCNO> 8346 </DOCNO>
Fractional Kramers Equation


  We introduce a fractional Kramers equation for a particle interacting with a
thermal heat bath and external non-linear force field. For the force free case
the velocity damping follows the Mittag-Leffler relaxation and the diffusion is
enhanced. The equation obeys the generalized Einstein relation, and its
stationary solution is the Boltzmann distribution. Our results are compared to
previous results on enhanced L\'evy type of diffusion derived from stochastic
collision models.

</DOC>
<DOC>
<DOCNO> 13043 </DOCNO>
Limits on the Curie temperature of (III,Mn)V ferromagnetic


  Mean-field-theory predicts that the Curie temperature T_c of a (III,Mn)V
ferromagnet will be proportional to the valence band density-of-states of its
host (III,V) semiconductor, suggesting a route toward room-temperature
ferromagnetism in this materials class. In this Letter, we use theoretical
estimates of spin-wave energies and Monte-Carlo simulations to demonstrate that
long-wavelength collective fluctuations, neglected by mean-field theory, will
limit the critical temperature in large density-of-states materials. We discuss
implications for high T_c searches.

</DOC>
<DOC>
<DOCNO> 40135 </DOCNO>
Exploration of Elastic Scattering Rates for Supersymmetric Dark Matter


  We explore the possible cross sections for the elastic scattering of
neutralinos chi on nucleons p,n in the minimal supersymmetric extension of the
standard model (MSSM). Universality of the soft supersymmetry-breaking scalar
masses for the Higgs multiplets is not assumed, but the MSSM parameters are
nevertheless required to lead consistently to an electroweak vacuum. We explore
systematically the region of MSSM parameter space where LEP and other
accelerator constraints are respected, and the relic neutralino density lies in
the range 0.1 < Omega_chi h^2 < 0.3 preferred by cosmology. We also discuss
models with Omega_chi h^2 < 0.1, in which case we scale the density of
supersymmetric dark matter in our galactic halo by Omega_chi h^2 / 0.1,
allowing for the possible existence of some complementary form of cold dark
matter. We find values of the cross sections that are considerably lower than
the present experimental sensitivities. At low neutralino masses, m_chi < 100
GeV, the cross sections may be somewhat higher than in the constrained MSSM
with universal soft Higgs masses, though they are generally lower. In the case
of large m_chi, the cross sections we find may be considerably larger than in
the constrained model, but still well below the present experimental
sensitivity.

</DOC>
<DOC>
<DOCNO> 12358 </DOCNO>
Electrical transport through carbon nanotube junctions created by


  Using an atomic force microscope we have created nanotube junctions such as
buckles and crossings within individual single-wall metallic carbon nanotubes
connected to metallic electrodes. The electronic transport properties of these
manipulated structures show that they form electronic tunnel junctions. The
conductance shows power-law behavior as a function of bias voltage and
temperature, which can be well modeled by a Luttinger liquid model for
tunneling between two nanotube segments separated by the manipulated junction.

</DOC>
<DOC>
<DOCNO> 11396 </DOCNO>
Identification of the physical parameters of the paramagnetic phase of


  The paramagnetic phase of the one-dimensional Kondo lattice model is
investigated for electron densities below half-filling using a new mean-field
approach. The physical parameters that govern this phase are identified to be
the spin-flip processes of both the localized and itinerant spins. A
nonmagnetic quantum state, where the local magnetization is a rotating vector
with a nonzero average length, is proposed in order to describe this phase.
This state does not break SU(2) symmetry in agreement with Mermin-Wagner
theorem. The line boundary between this phase and the ferromagnetic phase is
calculated in the coupling-density phase diagram. Also, expressions are
calculated for the velocities of the conduction electrons excitations, and heat
capacity and entropy versus temperature are analyzed. Good agreement with many
of the available numerical data is achieved.

</DOC>
<DOC>
<DOCNO> 118253 </DOCNO>
Formation of Molecular Gas in the debris of violent Galaxy Interactions


  In many gravitational interactions between galaxies, gas and stars that have
been torn from either or both of the precursor galaxies can collect in 'tidal
tails'. Star formation begins anew in these regions to produce 'tidal dwarf
galaxies', giving insight into the process of galaxy formation through the
well-defined timescale of the interaction. But tracking the star formation
process has proved to be difficult: the tidal dwarf galaxies with young stars
showed no evidence of the molecular gas out of which new stars form. Here we
report the discovery of molecular gas (carbon monoxide emission) in two tidal
dwarf galaxies. In both cases, the molecular gas peaks at the same location as
the maximum in atomic-hydrogen density, unlike most gas-rich galaxies. We infer
from this that the molecular gas formed from the HI, rather than being torn in
molecular form from the interacting galaxies. Star formation in the tidal
dwarfs appears to mimic that process in normal spiral galaxies like our own.

</DOC>
<DOC>
<DOCNO> 84819 </DOCNO>
Null limits of the C-metric


  The C-metric is usually understood as describing two black holes which
accelerate in opposite directions under the action of some conical singularity.
Here, we examine all the solutions of this type which represent accelerating
sources and investigate the null limit in which the accelerations become
unbounded. We show that the resulting space-times represent spherical impulsive
gravitational waves generated by snapping or expanding cosmic strings.

</DOC>
<DOC>
<DOCNO> 102716 </DOCNO>
Para, pseudo, and orthosupersymmetric quantum mechanics and their


  We consider the problem of bosonizing supersymmetric quantum mechanics (SSQM)
and some of its variants, i.e., of realizing them in terms of only boson-like
operators without fermion-like ones. In the SSQM case, this is realized in
terms of the generators of the Calogero-Vasiliev algebra (also termed deformed
Heisenberg algebra with reflection). In that of the SSQM variants, this is done
by considering generalizations of the latter algebra, namely the
$C_{\lambda}$-extended oscillator algebras, where $C_{\lambda}$ is the cyclic
group of order~$\lambda$.

</DOC>
<DOC>
<DOCNO> 69933 </DOCNO>
A neutrino mass matrix with seesaw mechanism and two-loop mass splitting


  We propose a model which uses the seesaw mechanism and the lepton number
$\bar L = L_e - L_\mu - L_\tau$ to achieve the neutrino mass spectrum $m_1 =
m_2$ and $m_3 = 0$, together with a lepton mixing matrix $U$ with $U_{e3} = 0$.
In this way, we accommodate atmospheric neutrino oscillations. A small mass
splitting $m_1 > m_2$ is generated by breaking $\bar L$ spontaneously and using
Babu's two-loop mechanism. This allows us to incorporate ``just so''
solar-neutrino oscillations with maximal mixing into the model. The resulting
mass matrix has three parameters only, since $\bar L$ breaking leads
exclusively to a non-zero $ee$ matrix element.

</DOC>
<DOC>
<DOCNO> 69425 </DOCNO>
The GUT Scale and Superpartner Masses from Anomaly Mediated


  We consider models of anomaly-mediated supersymmetry breaking (AMSB) in which
the grand unification (GUT) scale is determined by the vacuum expectation value
of a chiral superfield. If the anomaly-mediated contributions to the potential
are balanced by gravitational-strength interactions, we find a
model-independent prediction for the GUT scale of order $M_{\rm Planck} /
(16\pi^2)$. The GUT threshold also affects superpartner masses, and can easily
give rise to realistic predictions if the GUT gauge group is asymptotically
free. We give an explicit example of a model with these features, in which the
doublet-triplet splitting problem is solved. The resulting superpartner
spectrum is very different from that of previously considered AMSB models, with
gaugino masses typically unifying at the GUT scale.

</DOC>
<DOC>
<DOCNO> 120859 </DOCNO>
The Lens-Redshift Test Revisited


  Kochanek (1992) suggested that the redshifts of gravitational lens galaxies
rule out a large cosmological constant. This result was questioned by Helbig &
Kayser (1996), who pointed out that selection effects related to the brightness
of the lens can bias the results of this test against a high lambda value;
however, we did not claim that the observations favoured a high lambda value,
merely that current observational data were not sufficient to say either way,
using the test as proposed by Kochanek (1992) but corrected for selection
effects. Kochanek (1996) pointed out that additional information (fraction of
measured lens redshifts) provides additional information which restores the
sensitivity of the test to the cosmological model, at least somewhat. Here, I
consider three aspects. First, I examine the accuracy of the correction to the
test proposed by Kochanek (1996). Second, I compare the slightly different
statistical methods which have been used in connection with this test. Third, I
discuss what results can be obtained today now that more and better-defined
observations are available.

</DOC>
<DOC>
<DOCNO> 80650 </DOCNO>
Half-integer topological charges below and above the deconfinement


  For pure SU(2) lattice gauge theory at finite T, by the help of the cooling
method, we search for classical (approximate) solutions having non-trivial
holonomy at the spatial boundary. We identify various typical objects and
provide their relative frequency of occurence for the confinement and
deconfinement phases. Among the configurations obtained we see also the
dissociated BPS monopole pairs recently discussed by van Baal and
collaborators.

</DOC>
<DOC>
<DOCNO> 8999 </DOCNO>
The resistance anomaly in the surface layer of


  We observed that radio-frequency (rf) irradiation significantly enhances the
$c$-axis resistance near and below the superconducting transition of the
CuO$_{2}$ layer in contact with a normal-metal electrode on the surface of
Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+x}$ single crystals. We attribute the
resistance anomaly to the rf-induced charge-imbalance nonequilibrium effect in
the surface CuO$_{2}$ layer. The relaxation of the charge-imbalance in this
highly anisotropic system is impeded by the slow quasiparticle recombination
rate, which results in the observed excessive resistance.

</DOC>
<DOC>
<DOCNO> 151810 </DOCNO>
First Order Phase Transitions in a Bianchi type-I universe


  Considering the theory of induced gravity coupled to matter fields, taking
the $\phi ^6$ interaction potential model we evaluate the one-loop effective
potential in a (3+1)dimensional Bianchi type-I spacetime. It is proved that the
$\phi ^6$ theory can be regularised in (3+1)dimensional curved spacetime. We
evaluate the finite temperature effective potential and study the temperature
dependence of phase transitions. The nature of phase transitions in the early
universe is clarified to be of first order. The effects of spacetime curvature
and arbitrary field coupling on the phase transitions in the early universe are
also discussed.

</DOC>
<DOC>
<DOCNO> 8108 </DOCNO>
Spin-Dependent Josephson Current through Double Quantum Dots and


  We study a double quantum dot each dot of which is tunnel-coupled to
superconducting leads. In the Coulomb blockade regime, a spin-dependent
Josephson coupling between two superconductors is induced, as well as an
antiferromagnetic Heisenberg exchange coupling between the spins on the double
dot which can be tuned by the superconducting phase difference. We show that
the correlated spin states-singlet or triplets-on the double dot can be probed
via the Josephson current in a dc-SQUID setup.

</DOC>
<DOC>
<DOCNO> 80876 </DOCNO>
Precision study of large-N Yang-Mills theory in 2+1 dimensions


  The boundstate problem in 2+1-dimensional large-N Yang-Mills theory is
accurately solved using the light-front Hamiltonian of transverse lattice gauge
theory. We conduct a thorough investigation of the space of couplings on coarse
lattices, finding a single renormalised trajectory on which Poincar\'e
symmetries are enhanced in boundstate solutions. Augmented by existing data
from finite-N Euclidean lattice simulations, we obtain accurate estimates of
the low-lying glueball spectrum at N=infinty

</DOC>
<DOC>
<DOCNO> 174598 </DOCNO>
Proton-deuteron elastic scattering at low energies


  We present measurements of differential cross sections and the analyzing
powers A_y, iT11, T20, T21, and T22 at E_c.m.=431.3 keV. In addition, an
excitation function of iT11(theta_c.m.=87.8 degrees) for 431.3 <= E_c.m. <=
2000 keV is presented. These data are compared to calculations employing
realistic nucleon-nucleon interactions, both with and without three-nucleon
forces. Excellent agreement with the tensor analyzing powers and cross section
is found, while the Ay and iT11 data are found to be underpredicted by the
calculations.

</DOC>
<DOC>
<DOCNO> 72107 </DOCNO>
Random values of the physical parameters


  I briefly describe two motivations, two mechanisms and two possible tests of
the hypothesis that the physical parameters of the ground state of a theory can
vary in different regions of the universe.

</DOC>
<DOC>
<DOCNO> 150901 </DOCNO>
Multiloop String Amplitudes with B-Field and Noncommutative QFT


  The multiloop amplitudes for the bosonic string in presence of a constant
B-field are built by using the basic commutation relations for the open string
zero modes and oscillators. The open string Green function on the annulus is
obtained from the one loop scattering amplitude among N tachyons. For higher
loops, it is necessary to use the so called three Reggeon vertex, which
describes the emission from the open string of another string and not simply of
a tachyon. We find that the modifications to the three (and multi) Reggeon
vertex due to the B-field only affect the zero modes and can be written in a
simple and elegant way. Therefore we can easily sew these vertices together and
write the general expression for the multiloop N-Reggeon vertex, which contains
any loop string amplitude, in presence of the B-field. The field theory limit
is also considered in some examples at two loops and reproduces exactly the
results of a noncommutative scalar field theory.

</DOC>
<DOC>
<DOCNO> 12194 </DOCNO>
Structural Susceptibilities in Toy Models of Proteins


  New definitions of the structural susceptibilities based on the fluctuations
of distances to the native state of toy protein models are proposed. The
calculation of such susceptibilities does not require the basin of native state
and the folding temperature can be defined from their peak if the native
conformation is compact. The number of peaks in the derivatives of distances to
the native state with respect to temperature, when plotted versus temperature,
may serve as a criterion for foldability. The thermodynamics quantities are
obtained by Monte Carlo and molecular dynamics simulations.

</DOC>
<DOC>
<DOCNO> 169774 </DOCNO>
About the Dirac Equation with a $\delta$ potential


  An elementary treatment of the Dirac Equation in the presence of a
three-dimensional spherically symmetric $\delta (r-r_0)$-potential is
presented. We show how to handle the matching conditions in the configuration
space, and discuss the occurrence of supercritical effects.

</DOC>
<DOC>
<DOCNO> 40249 </DOCNO>
Astrophysical neutrinos: 20th Century and Beyond


  I summarize the first four decades of solar neutrino research and suggest
what may be possible to learn with extragalactic neutrinos and with solar
neutrinos in the next decade.

</DOC>
<DOC>
<DOCNO> 100071 </DOCNO>
Geometry of Quaternionic K\"ahler connections with torsion


  The target space of a (4,0) supersymmetric two-dimensional sigma model with
Wess-Zumino term has a connection with totally skew-symmetric torsion and
holonomy contained in Sp(n).Sp(1), QKT-connection. We study the geometry of
QKT-connections. We find conditions to the existence of a QKT-connection and
prove that if it exists it is unique. Studying conformal transformations we
obtain a lot of (compact) examples of QKT manifolds. We present a (local)
description of 4-dimensional homogeneous QKT structures relying on the known
result of naturally reductive homogeneous Riemannian manifolds. We consider
Einstein-like QKT manifold and find closed relations with Einstein-Weyl
geometry in dimension four.

</DOC>
<DOC>
<DOCNO> 85176 </DOCNO>
Dust-filled axially symmetric universes with a cosmological constant


  Following the recent recognition of a positive value for the vacuum energy
density and the realization that a simple Kantowski-Sachs model might fit the
classical tests of cosmology, we study the qualitative behavior of three
anisotropic and homogeneous models: Kantowski-Sachs, Bianchi type-I and Bianchi
type-III universes, with dust and a cosmological constant, in order to find out
which are physically permitted. We find that these models undergo
isotropization up to the point that the observations will not be able to
distinguish between them and the standard model, except for the Kantowski-Sachs
model $(\Omega_{k_{0}}<0)$ and for the Bianchi type-III $(\Omega_{k_{0}}>0)$
with $\Omega_{\Lambda_{0}}$ smaller than some critical value
$\Omega_{\Lambda_{M}}$. Even if one imposes that the Universe should be nearly
isotropic since the last scattering epoch ($z\approx 1000$), meaning that the
Universe should have approximately the same Hubble parameter in all directions
(considering the COBE 4-Year data), there is still a large range for the matter
density parameter compatible with Kantowsky-Sachs and Bianchi type-III if
$|\Omega_0+\Omega_{\Lambda_0}-1|\leq \delta$, for a very small $\delta$ . The
Bianchi type-I model becomes exactly isotropic owing to our restrictions and we
have $\Omega_0+\Omega_{\Lambda_0}=1$ in this case. Of course, all these models
approach locally an exponential expanding state provided the cosmological
constant $\Omega_\Lambda>\Omega_{\Lambda_{M}}$.

</DOC>
<DOC>
<DOCNO> 84202 </DOCNO>
Gravitational Solitons and Monodromy Transform Approach to Solution of


  In this paper the well known Belinskii and Zakharov soliton generating
transformations of the solution space of vacuum Einstein equations with
two-dimensional Abelian groups of isometries are considered in the context of
the so called "monodromy transform approach", which provides some general base
for the study of various integrable space - time symmetry reductions of
Einstein equations. Similarly to the scattering data used in the known spectral
transform, in this approach the monodromy data for solution of associated
linear system characterize completely any solution of the reduced Einstein
equations, and many physical and geometrical properties of the solutions can be
expressed directly in terms of the analytical structure on the spectral plane
of the corresponding monodromy data functions. The Belinskii and Zakharov
vacuum soliton generating transformations can be expressed in explicit form
(without specification of the background solution) as simple
(linear-fractional) transformations of the corresponding monodromy data
functions with coefficients, polynomial in spectral parameter. This allows to
determine many physical parameters of the generating soliton solutions without
(or before) calculation of all components of the solutions. The similar
characterization for electrovacuum soliton generating transformations is also
presented.

</DOC>
<DOC>
<DOCNO> 178458 </DOCNO>
Phenomenological local potentials for \pi^- + ^{12}C scattering from 120


  Pion-nucleus scattering cross sections are calculated by solving a
Schr\"{o}dinger equation reduced from the Klein-Gordon equation. Local
potentials are assumed, and phenomenological potential parameters are searched
energy-dependently for $\pi^{-} + ^{12}$C system so as to reproduce not only
elastic differential cross sections but also total elastic, reaction and total
cross sections at 13 pion incident energies from 120 to 766 MeV. The real and
imaginary parts of the local potentials thus obtained are shown to satisfy the
dispersion relation. The imaginary part of the potentials as a function of the
pion energy is found to peak near the $\Delta$(1232)-resonance energy. The
strong absorption radius of the pion projectile with incident energies near the
$\Delta$-resonance region is found to be about $1.6 A^{1/3}$ fm, which is
consistent with previous studies of the region where the decay of the
$\Delta$'s takes place in nuclei. The phenomenological local potentials are
then compared with the local potentials exactly phase-shift equivalent to
Kisslinger potentials for pion energies near the $\Delta$-resonance.

</DOC>
<DOC>
<DOCNO> 151933 </DOCNO>
Two-loop effective potential in noncommutative scalar field theory


  The renormalization of effective potential for the noncommutative scalar
field theory is investigated to the two-loop approximation. It is seen that the
nonplanar diagram does not appear in the one-loop potential. However, nonplanar
diagram can become dominant in the two-loop level as the noncommutativity of
geometry is sufficiently small. The result shows that the radiative corrections
from the nonplanar diagrams have an inclination to induce the spontaneously
symmetry breaking if it is not broken in the tree level, and have an
inclination to restore the symmetry breaking if it has been broken in the tree
level.

</DOC>
<DOC>
<DOCNO> 12907 </DOCNO>
Initial-state dependence in time-dependent density functional theory


  Time-dependent density functionals in principle depend on the initial state
of the system, but this is ignored in functional approximations presently in
use. For one electron it is shown there is no initial-state dependence: for any
density, only one initial state produces a well-behaved potential. For two
non-interacting electrons with the same spin in one-dimension, an initial
potential that makes an alternative initial wavefunction evolve with the same
density and current as a ground state is calculated. This potential is
well-behaved and can be made arbitrarily different from the original potential.

</DOC>
<DOC>
<DOCNO> 9957 </DOCNO>
Anomalous crossover between thermal and shot noise in macroscopic


  We predict the existence of an anomalous crossover between thermal and shot
noise in macroscopic diffusive conductors. We first show that, besides thermal
noise, these systems may also exhibit shot noise due to fluctuations of the
total number of carriers in the system. Then we show that at increasing
currents the crossover between the two noise behaviors is anomalous, in the
sense that the low frequency current spectral density displays a region with a
superlinear dependence on the current up to a cubic law. The anomaly is due to
the non-trivial coupling in the presence of the long range Coulomb interaction
among the three time scales relevant to the phenomenon, namely, diffusion,
transit and dielectric relaxation time.

</DOC>
<DOC>
<DOCNO> 99900 </DOCNO>
Periodic and almost periodic potentials in the inverse problems


  We review basic ideas and basic examples of the theory of the inverse
spectral problems.

</DOC>
<DOC>
<DOCNO> 101721 </DOCNO>
Berezin quantization of the Schrodinger algebra


  We examine the Schrodinger algebra in the framework of Berezin quantization.
First, the Heisenberg-Weyl and sl(2) algebras are studied. Then the Berezin
representation of the Schrodinger algebra is computed. In fact, the sl(2) piece
of the Schrodinger algebra can be decoupled from the Heisenberg component. This
is accomplished using a special realization of the sl(2) component that is
built from the Heisenberg piece as the quadratic elements in the
Heisenberg-Weyl enveloping algebra. The structure of the Schrodinger algebra is
revealed in a lucid way by the form of the Berezin representation.

</DOC>
<DOC>
<DOCNO> 120393 </DOCNO>
Integral field spectroscopy of the radio galaxy 3C 171


  We have performed integral field spectroscopy of the radio galaxy 3C 171
(redshift z=0.238) with the TIGER instrument at the Canada France Hawaii
telescope in the Hbeta-[OIII]4959-5007 wavelength region. We present the
reconstructed Hbeta and [OIII] images and compare them to the HST and radio
maps. We discuss the variations of the [OIII]/Hbeta line ratio throughout the
nebulosity. We also analyze the velocity field in detail, in particular the
presence of several components. We find that the kinematics derived with
emission lines in the central region (inside 1 arcsec) are compatible with a
disk-like rotation of low amplitude (50 km/s). The continuum surface brightness
profile follows an r^{1/4} law, suggesting that the underlying galaxy is an
elliptical with an effective radius of 15 kpc.
  We have fit two components in the region centered 2.7 arcsec to the West and
of extension 3 arcsec^2. We find that the blueshifted component is an extension
of the central part, whereas the second one is redshifted by 600 km/s. In both
components, line ratios and FWHM are compatible with the presence of shocks
induced by jet-cloud interactions.

</DOC>
<DOC>
<DOCNO> 11763 </DOCNO>
Comment on "Spinless impurities in High-Tc Cu-prates: Kondo-like


  The recent obervation of a Kondo-like temperature dependence in the Li NMR
Knight shift in Ca- and Li- cosubstituted YBa2Cu3O7-d was attributed by Bobroff
et al. to be evidence of Li-induced local moments in overdoped Y123. It is
shown from Y-NMR measurements on Y0.8Ca0.2Ba2Cu3O7-d and heat capacity studies
on Bi2Sr2CaCu2O8 that such a Kondo-like temperature dependence is an intrinsic
overdoping effect quite generally present in cuprate superconductors which are
free of strong scatterers such as Zn and Li. It is probable that Zn and Li only
induce local moments in the underdoped pseudogap region and not in the
overdoped region.

</DOC>
<DOC>
<DOCNO> 122863 </DOCNO>
Does Light Gravitate? (Proposal on New Test of Equivalence Principle)


  On the basis of the relativistic mass-energy concept we found that a proper
mass of a test particle in a gravitational field depends on a potential energy,
hence, a freely falling particle has a varying proper mass. Consequently, a
multitude of freely falling reference frames cannot be regarded as the
multitude of equivalent inertial reference frames. There is a class of
experiments, which allow distinguishing between them. If so, a demonstration of
a violation of the Equivalence Principle is possible. It is shown that a
variant of the classical Pound-Rebka-Snider experiment on a photon frequency
shift in a gravitational field if conducted in a freely falling laboratory
would be such a test.

</DOC>
<DOC>
<DOCNO> 11948 </DOCNO>
Fractional vortices in the XY model with $\pi$ bonds


  We define a new set of excitations in the XY model which we call ``fractional
vortices''. In the frustrated XY model containing $\pi$ bonds, we make the
ansatz that the ground state configurations can be characterized by pairs of
oppositely charged fractional vortices. For a chain of $\pi$ bonds, the ground
state energy and the phase configurations calculated on the basis of this
ansatz agree well with the results from direct numerical simulations. Finally,
we discuss the possible connection of these results to some recent experiments
by Kirtley {\it et al} [Phys. Rev. B {\bf 51}, R12057 (1995)] on high-T$_c$
superconductors where fractional flux trapping was observed along certain grain
boundaries.

</DOC>
<DOC>
<DOCNO> 13673 </DOCNO>
Bose-Einstein condensates in symmetry breaking states


  We consider two models of interacting Bose gases: a gas of spin one particles
in the ground state of a cubic box and a one-dimension Bose gas with contact
interactions. We show how to calculate exact eigenstates of the corresponding
N-body Hamiltonians. Both models share the property of not leading to the
formation of a Bose-Einstein condensate, even at zero temperature, in the
strict sense of the existence of a single one-particle state with a macroscopic
population. We show that a lot of physical insight can be gained on these two
model systems by using the usual Hartree-Fock mean field approach: in this
approximation, that we test against the exact result, everything happens as if
a single realization of the system was a Bose-Einstein condensate in a state
phi breaking the rotational or translational symmetry, and varying in a random
way for any new experimental realization.

</DOC>
<DOC>
<DOCNO> 83369 </DOCNO>
The definition of a random sequence of qubits: from Noncommutative


  The issue of defining a random sequence of qubits is studied in the framework
of Algorithmic Free Probability Theory.Its connection with Quantum Algorithmic
Information Theory is shown

</DOC>
<DOC>
<DOCNO> 122245 </DOCNO>
Self-broadening in Balmer line wing formation in stellar atmospheres


  Details of a theory of self-broadening of hydrogen lines are presented. The
main features of the new theory are that the dispersive-inductive components of
the interaction (van der Waals forces) have been included, and the resonance
components have been computed by perturbation theory without the use of the
multipole expansion. The theory is applied to lower Balmer lines and the
theoretical and observational impact of the new broadening theory is examined.
It is shown that this theory leads to considerable differences in the predicted
line profiles in cool stars when compared with previous theories which include
only resonance interactions. In particular, the effect is found to be very
important in metal poor stars. The theory provides a natural explanation for
the behaviour of effective temperatures derived from Balmer lines by others
using a theory which includes only resonance broadening. When applied to Balmer
lines in the solar spectrum the theory predicts an improved agreement between
observed and computed profiles for models which also match limb darkening
curves and rules out a model which does not. However significant discrepancies
still remain which could be due to inadequacies in our theory or the
atmospheric model or both.

</DOC>
<DOC>
<DOCNO> 11331 </DOCNO>
Inelastic tunneling in a double quantum dot coupled to a bosonic


  Coupling a quantum system to a bosonic environment always give rise to
inelastic processes, which reduce the coherency of the system. We measure
energy dependent rates for inelastic tunneling processes in a fully
controllable two-level system of a double quantum dot. The emission and
absorption rates are well repro-duced by Einstein's coefficients, which relate
to the spontaneous emission rate. The inelastic tunneling rate can be
comparable to the elastic tunneling rate if the boson occupation number becomes
large. In the specific semiconductor double dot, the energy dependence of the
inelastic rate suggests that acoustic phonons are coupled to the double dot
piezoelectrically.

</DOC>
<DOC>
<DOCNO> 119410 </DOCNO>
Resolved Stellar Populations of Super-Metal-Rich Star Clusters in the


  We have applied the MCS image deconvolution algorithm (Magain, Courbin & Sohy
1998) to HST/WFPC2 V, I data of three M31 bulge globular clusters (G170, G177,
and G198) and control fields near each cluster. All three clusters are clearly
detected, with an increase in stellar density with decreasing radius from the
cluster centers; this is the first time that stars have been resolved in bulge
clusters in the inner regions of another galaxy. From the RGB slopes of the
clusters and the difference in I magnitude between the HB and the top of the
RGB, we conclude that these three clusters all have roughly solar metallicity,
in agreement with earlier integrated-light spectroscopic measurements. Our data
support a picture whereby the M31 bulge clusters and field stars were born from
the same metal-rich gas, early in the galaxy formation.

</DOC>
<DOC>
<DOCNO> 40392 </DOCNO>
The Probability Density of the Higgs Boson Mass


  The LEP Collaborations have reported a small excess of events in their
combined Higgs boson analysis at center of mass energies up to about 208 GeV.
In this communication, I present the result of a calculation of the probability
distribution function of the Higgs boson mass which can be rigorously obtained
if the validity of the Standard Model is assumed. It arises from the
combination of the most recent set of precision electroweak data and the
current results of the Higgs searches at LEP 2.

</DOC>
<DOC>
<DOCNO> 152127 </DOCNO>
Exploiting duality in a toy model of QCD at non-zero temperature and


  We focus on the massive Thirring model in 1+1 dimensions at finite
temperature and non-zero chemical potential, and comment on some parallels
between this model and QCD. In QCD, calculations of physical quantities such as
transport coefficients are extremely difficult. In the massive Thirring model,
similar calculations are greatly simplified by exploiting the duality which
exists with the sine-Gordon model and its relation, at high temperature, to the
exactly solvable classical Coulomb gas on the line.

</DOC>
<DOC>
<DOCNO> 118157 </DOCNO>
Determination of the EAS Attenuation Length from Data of the ANI


  Using the EAS size spectra measured with the MAKET ANI array on Mt. Aragats,
Armenia (3200m a.s.l.) in the range of the shower size 10^5 - 10^7 for
different angles-of-incidence, the EAS attenuation length has been determined
applying different analysis methods. The analysis is based on a data sample of
2.5*10^6 events collected in the period of June, 97 - April, 99. The results
are compared with results deduced from data of the EAS TOP and KASCADE
experiments.

</DOC>
<DOC>
<DOCNO> 151821 </DOCNO>
Superembedding Approach and S-Duality. A unified description of


  It is proved that a basic superembedding equation for the 2-dimensional
worldsheet superspace $\S^{(2|8+8)}$ embedded into D=10 type IIB superspace
$M^{(10|16+16)}$ provides a universal, S-duality invariant description of a
fundamental superstring and super-D1-brane. We work out generalized action
principle, obtain superfield equations of motion for both these objects and
find how the S-duality transformations relate the superfield equations of
superstring and super-D1-brane.
  The superembedding of 6-dimensional worldsheet superspace $\S^{(6|16)}$ into
the D=10 type IIB superspace will probably provide a similar universal
description for the set of type IIB super-NS5-brane, super-D5-brane and a
Kaluza-Klein monopole (super-KK5-brane).

</DOC>
<DOC>
<DOCNO> 150448 </DOCNO>
Gauge Theory on Noncommutative Spaces


  We introduce a formulation of gauge theory on noncommutative spaces based on
the concept of covariant coordinates. Some important examples are discussed in
detail. A Seiberg-Witten map is established in all cases.

</DOC>
<DOC>
<DOCNO> 101866 </DOCNO>
Standard Complex for Quantum Lie Algebras


  For a quantum Lie algebra $\Gamma$, let $\Gamma^\wedge$ be its exterior
extension (the algebra $\Gamma^\wedge$ is canonically defined). We introduce a
differential on the exterior extension algebra $\Gamma^\wedge$ which provides
the structure of a complex on $\Gamma^{\wedge}$. In the situation when $\Gamma$
is a usual Lie algebra this complex coincides with the "standard complex". The
differential is realized as a commutator with a (BRST) operator $Q$ in a larger
algebra $\Gamma^\wedge[\Omega]$, with extra generators canonically conjugated
to the exterior generators of $\Gamma^{\wedge}$. A recurrent relation which
defines uniquely the operator $Q$ is given.

</DOC>
<DOC>
<DOCNO> 84689 </DOCNO>
Contraction and distension by tidal stress and its role as the cause of


  I show that a cumulative contraction or expansion must result from repetitive
tidal action in a curved stress field, depending on the direction of the
curvature. The resulting expansion of solid materials onboard deep space probes
and the corresponding contraction on earth would be of the right magnitude to
account for all aspects of the Pioneer anomaly, leading to the two component
model previously proposed. Importantly, I show via signal path analysis that
the anomaly mathematically implies planetary Hubble flow, and that it is
predicted by the standard model equations when the cosmological constant is
also taken into account at this range. Also shown is that the variations of the
anomaly do not permit a different explanation. The prediction of the Hubble
flow occurring as a result in the view of the shrinking observer is now fully
explained from both quantum and Doppler perspectives, fundamentally challenging
the cosmological ideas of the past century. Lastly, I discuss how the
contraction reconciles the geological evidence of a past expansion of the
earth.

</DOC>
<DOC>
<DOCNO> 8422 </DOCNO>
Influence of center-of-mass correlations on spontaneous emission and


  Local field effects on the rate of spontaneous emission and Lamb shift in a
dense gas of atoms are discussed taking into account correlations of atomic
center-of-mass coordinates. For this the exact retarded propagator in the
medium is calculated in independent scattering approximation and employing a
virtual-cavity model. The resulting changes of the atomic polarizability lead
to modifications of the medium response which can be of the same order of
magnitude but of opposite sign than those due to local field corrections of the
dielectric function derived by Morice, Castin, and Dalibard [Phys.Rev.A 51,
3896 (1995)].

</DOC>
<DOC>
<DOCNO> 150468 </DOCNO>
Compactification, Geometry and Duality: N=2


  These are notes based on lectures given at TASI99. We review the geometry of
the moduli space of N=2 theories in four dimensions from the point of view of
superstring compactification. The cases of a type IIA or type IIB string
compactified on a Calabi-Yau threefold and the heterotic string compactified on
K3xT2 are each considered in detail. We pay specific attention to the
differences between N=2 theories and N>2 theories. The moduli spaces of vector
multiplets and the moduli spaces of hypermultiplets are reviewed. In the case
of hypermultiplets this review is limited by the poor state of our current
understanding. Some peculiarities such as ``mixed instantons'' and the
non-existence of a universal hypermultiplet are discussed.

</DOC>
<DOC>
<DOCNO> 68013 </DOCNO>
Alternative Solutions to Big Bang Nucleosynthesis


  Standard big bang nucleosynthesis (SBBN) has been remarkably successful, and
it may well be the correct and sufficient account of what happened. However,
interest in variations from the standard picture come from two sources: First,
big bang nucleosynthesis can be used to constrain physics of the early
universe. Second, there may be some discrepancy between predictions of SBBN and
observations of abundances. Various alternatives to SBBN include inhomogeneous
nucleosynthesis, nucleosynthesis with antimatter, and nonstandard neutrino
physics.

</DOC>
<DOC>
<DOCNO> 117058 </DOCNO>
A Generalization of the Maximum Noise Fraction Transform


  A generalization of the maximum noise fraction (MNF) transform is proposed.
Powers of each band are included as new bands before the MNF transform is
performed. The generalized MNF (GMNF) is shown to perform better than the MNF
on a time dependent airborne electromagnetic (AEM) data filtering problem.

</DOC>
<DOC>
<DOCNO> 85258 </DOCNO>
Generalized Hubble law, violation of the cosmological principle and


  The acceleration of the cosmic expansion has been discovered as a consequence
of redshift Supernovae data. In the usual way, this cosmic acceleration is
explained by the presence of a positive cosmological constant or quantum vacuum
energy, in the background of standard Friedmann models. Recently, looking for
an alternative explanation, I have considered an inhomogeneous barotropic
spherically symmetric spacetime. Obviously, in this inhomogeneous model the
philosophical cosmological principle is not verified. Within this framework,
the kinematical acceleration of the cosmic fluid or, equivalently, the
inhomogeneity of matter, is just the responsible of the SNe Ia measured cosmic
acceleration. Moreover, this model gives rise to a generalized Hubble law with
two anisotropic terms (dipole acceleration and quadrupole shear), besides the
expansion one. The dipole term of this generalized Hubble law could explain, in
a cosmological setting, the observed large scale flow of matter, without to
have recourse to peculiar velocity-type newtonian models which assume a Doppler
dipole.

</DOC>
<DOC>
<DOCNO> 169707 </DOCNO>
Temperature dependence of the Casimir effect between metallic mirrors


  We calculate the Casimir force and free energy for plane metallic mirrors at
non-zero temperature. Numerical evaluations are given with temperature and
conductivity effects treated simultaneously. The results are compared with the
approximation where both effects are treated independently and the corrections
simply multiplied. The deviation between the exact and approximated results
takes the form of a temperature dependent function for which an analytical
expression is given. The knowledge of this function allows simple and accurate
estimations at the % level.

</DOC>
<DOC>
<DOCNO> 39620 </DOCNO>
High energy photon colliders


  Using the laser backscattering method at future linear colliders one can
obtain gamma-gamma and gamma-electron colliding beams (photon colliders) with
energy and luminosity comparable to that in e^+e^- collisions. This option has
been included in the pre-conceptual designs of linear colliders and in work on
a Technical Design Report which is in progress. The physics motivation for
photon colliders is quite clear. The proof of its technical feasibility and the
search for the best solutions is of first priority now. A key element of a
photon collider is a laser with high peak power and repetition rate. One very
promising way to overcome this problem is the optical cavity approach which is
discussed in this paper. A very high gamma-gamma luminosity could be achieved
by further decreasing the beam emittances. This will be very challenging. One
possible way is laser cooling of electron beams. This method is discussed in my
second talk at this symposium. The solution to the first problem is vital for
photon colliders and provides an interesting physics program. Solution of the
second problem makes photon colliders a very powerful instrument for study of
matter, the best for study of many phenomena. How to achieve these goals is the
subject of this talk.

</DOC>
<DOC>
<DOCNO> 10555 </DOCNO>
Magnetostructural effects and phase transition in Cr_2O_3 under pressure


  We have successfully calculated the electronic and structural properties of
chromia (Cr_2O_3) in the Local Spin Density Approximation (LSDA). We predict a
transformation from the corundum to the Rh_2O_3(II) structure around 15 GPa in
the anti-ferromagnetic (AFM) phase as well as in the paramagnetic (PM)
insulating state which occurs above the Neel temperature (T_N). This transition
is relevant to interpreting the optical anomalies observed in the absorption
spectrum of ruby under pressure. We have modeled the structural properties of
the PM state using a Landau-like expansion of the magnetostriction energy. This
treatment correctly describes the structural anomalies across T_N in the
corundum phase and indicates that the AFM and PM insulating states should have
distinct compressive behaviors.

</DOC>
<DOC>
<DOCNO> 40225 </DOCNO>
Deep inelastic scattering on asymmetric nuclei


  We study deep inelastic scattering on isospin asymmetric nuclei. In
particular, the difference of the nuclear structure functions and the Gottfried
sum rule for the lightest mirror nuclei, 3He and 3H, are investigated. It is
found that such systems can provide significant information on charge symmetry
breaking and flavor asymmetry in the nuclear medium. Furthermore, we propose a
new method to extract the neutron structure function from radioactive isotopes
far from the line of stability. We also discuss the flavor asymmetry in the
Drell-Yan process with isospin asymmetric nuclei.

</DOC>
<DOC>
<DOCNO> 7888 </DOCNO>
XANES study of rare-earth valency in LRu4P12 (L = Ce and Pr)


  Valency of Ce and Pr in LRu4P12 (L = Ce and Pr) was studied by L2,3-edge
x-ray absorption near-edge structure (XANES) spectroscopy. The Ce-L3 XANES
spectrum suggests that Ce is mainly trivalent, but the 4f state strongly
hybridizes with ligand orbitals. The band gap of CeRu4P12 seems to be formed by
strong hybridization of 4f electrons. Pr-L2 XANES spectra indicate that Pr
exists in trivalent state over a wide range in temperature, 20 < T < 300 K. We
find that the metal-insulator (MI) transition at TMI = 60 K in PrRu4P12 does
not originate from Pr valence fluctuation.

</DOC>
<DOC>
<DOCNO> 178785 </DOCNO>
Relativistic Heavy--Ion Collisions in the Dynamical String--Parton Model


  We develop and extend the dynamical string parton model. This model, which is
based on the salient features of QCD, uses classical Nambu-Got\=o strings with
the endpoints identified as partons, an invariant string breaking model of the
hadronization process, and interactions described as quark-quark interactions.
In this work, the original model is extended to include a phenomenological
quantization of the mass of the strings, an analytical technique for treating
the incident nucleons as a distribution of string configurations determined by
the experimentally measured structure function, the inclusion of the gluonic
content of the nucleon through the introduction of purely gluonic strings, and
the use of a hard parton-parton interaction taken from perturbative QCD
combined with a phenomenological soft interaction. The limited number of
parameters in the model are adjusted to $e^+e^-$ and $p $--$p$ data. Utilizing
these parameters, the first calculations of the model for $p $--$A$ and
$A$--$A$ collisions are presented and found to be in reasonable agreement with
a broad set of data.

</DOC>
<DOC>
<DOCNO> 170290 </DOCNO>
Speed-up and entanglement in quantum searching


  Grover's algorithm on pure states naturally generates entanglement during
computation. For pseudo-pure state implementations we show that not only is
entanglement necessary to achieve a speed-up, but it must be present throughout
the computation. Despite the non-asymptotic character of this result we find
that it only unambiguously applies to ensemble implementations, such as in
liquid-state NMR, for asymptotically large search spaces. This ambiguity and
its implications for interpreting a claimed speed-up in existing NMR based
quantum searches is discussed.

</DOC>
<DOC>
<DOCNO> 123197 </DOCNO>
The Quiescent X-Ray Spectrum of the Neutron Star in Cen X-4 Observed


  We report on spectral and intensity variability analysis from a
Chandra/ACIS-S observation of the transient, type-I X-ray bursting low-mass
X-ray binary Cen X-4. The quiescent X-ray spectrum during this observation is
statistically identical to one observed previously with Beppo/SAX, and close,
but not identical, to one observed previously with ASCA. The X-ray spectrum is
best described as a pure Hydrogen atmosphere thermal spectrum plus a power-law
component that dominates the spectrum above 2 keV. The best-fit radius of the
neutron star is r=12.9+/-2.6 (d/1.2 kpc) km if the interstellar absorption is
fixed at the value implied by the optical reddening. Allowing the interstellar
absorption to be a free parameter yields r=19+45-10 (d/1.2 kpc) km (90%
confidence). The thermal spectrum from the neutron star surface is inconsistent
with a solar metallicity. We find a 3sigma upper-limit of root-mean-square
variability <18% (0.2-2.0 keV; 0.0001-1 Hz) during the observation. On the
other hand, the 0.5-10.0 keV luminosity decreased by 40+/-8% in the 4.9 years
between the Asca and Chandra observations. This variability can be attributed
to the power-law component. Moreover, we limit the variation in thermal
temperature to <10% over these 4.9 years. The stability of the thermal
temperature and emission area radius supports the interpretation that the
quiescent thermal emission is due to the hot neutron star core.

</DOC>
<DOC>
<DOCNO> 121530 </DOCNO>
Search for High Proper Motion White Dwarfs


  Recent results of microlensing surveys, show that 10-20% of the dark halo
mass of the Milky Way consists of compact objects. The masses of these compact
objects range from 0.1 to 1 solar mass. New theoretical cooling models for
white dwarfs, and the detection of faint blue high proper motion objects, imply
that ancient white dwarfs might make up part of this population. In this pilot
project, using data from the C and D patches of the ESO Imaging Survey and data
obtained at CTIO, we attempted to find such halo white dwarfs in the solar
neighbourhood. With a time baseline of approximately one year between data sets
and a limiting I-band magnitude of 23, we can find these high proper motion
objects up to distances of 85 parsecs. In the 2.5 square degrees studied so far
we have found three high proper motion candidates.

</DOC>
<DOC>
<DOCNO> 70113 </DOCNO>
Quark level linear \sigma model (L\sigma M) via loop graphs


  First, the L\sigma M is nonperturbatively solved via loop-order gap
equations. Then the Nambu-Goldstone theorem (NGT) is expressed in L\sigma M
language. Next, the Lee null tadpole sum for this SU(2) L\sigma M theory is
shown to require N_c = 3. Then L\sigma M s-wave chiral cancellations are
studied in tree-and in loop-order. Also, vector meson dominance (VMD) is shown
to follow from this L\sigma M. Next, the scalar nonet is studied in the
infinite momentum frame (IMF). Finally, the L\sigma M is suggested as the
infrared limit of nonperturbative QCD.

</DOC>
<DOC>
<DOCNO> 118695 </DOCNO>
Depletion curves in cluster lenses: simulations and application to the


  When the logarithmic slope of the galaxy counts is lower than 0.4 (this is
the case in all filters at large magnitude), the magnification bias due to the
lens makes the number density of objects decrease, and consequently, the radial
distribution shows a typical depletion curve. In this paper, we present
simulations of depletion curves obtained in different filters for a variety of
different lens models - e.g., a singular isothermal sphere, an isothermal
sphere with a core, a power-law density profile, a singular isothermal
ellipsoid and a NFW profile. The different model parameters give rise to
different effects, and we show how the filters, model parameters and redshift
distributions of the background populations affect the depletion curves. We
then compare our simulations to deep VLT observations of the cluster
MS1008--1224 and propose to constrain the mass profile of the cluster as well
as the ellipticity and the orientation of the mass distribution. This
application is based solely on deep photometry of the faint background
galaxies. We finally give some possible applications of this method, useful for
cluster lenses.

</DOC>
<DOC>
<DOCNO> 169894 </DOCNO>
Stability and instability in parametric resonance and quantum Zeno


  A quantum mechanical version of a classical inverted pendulum is analyzed.
The stabilization of the classical motion is reflected in the bounded evolution
of the quantum mechanical operators in the Heisenberg picture. Interesting
links with the quantum Zeno effect are discussed.

</DOC>
<DOC>
<DOCNO> 85605 </DOCNO>
New matrix formalism for heterotic string theory on a torus


  A new Lagrange formalism based on the use of a single scalar (d+1)X(d+1+n)
matrix potential is developed for the low-energy heterotic string theory with n
U(1) gauge fields compactified from d+3 to 3 dimensions on a torus. This
formalism also includes three pairs on-shell defined scalar and vector matrix
potentials of the dimensions (d+1)X(d+1), (d+1)X(d+1+n) and (d+1+n)X(d+1+n).
All these potentials undergo linear transformations when the group of charging
symmetries acts.

</DOC>
<DOC>
<DOCNO> 70896 </DOCNO>
Monte Carlo simulation for jet fragmentation in SUSY-QCD


  We present results from a new Monte Carlo simulation for jet fragmentation in
QCD and SUSY QCD for large primary energies $\sqrt s$ up to $10^{16}$ GeV. In
the case of SUSY QCD the simulation takes into account not only gluons and
quarks as cascading particles, but also their supersymmetric partners. A new
model-independent hadronization scheme is developed, in which the hadronization
functions are found from LEP data. An interesting feature of SUSY QCD is the
prediction of a sizeable flux of the lightest supersymmetric particles (LSPs),
if R-parity is conserved. About 10% of the jet energy is transferred to LSPs
which, owing to their harder spectra, constitute an important part of the
spectra for large $x=E/E_{jet}$. Spectra of protons and of secondary particles,
photons and neutrinos, are also calculated. These results have implications for
the decay of superheavy particles with masses up to the GUT scale, which have
been suggested as a source of ultrahigh energy cosmic rays.

</DOC>
<DOC>
<DOCNO> 102247 </DOCNO>
A Historical Perspective on the Topology and Physics of Hyperspace


  This paper examines the history of the development of dimensional analysis,
from Euclidean geometry to hyperspace. This is largely a secondary source work
intended to summarize, as briefly as possible, with enough mathematical rigor,
the mathematical developments in dimensional analysis over the past 2550 years.
It is intended to stimulate further research and interest in the topic while
also presenting a few original thoughts on certain aspects of the subject. In
particular, the paper focuses on the development of Euclidean geometry, the
intense study of the parallel axiom in the 1800's, the development of time as a
dimension leading to Kaluza-Klein theory, and finally the explosion of work in
the combined areas of string theory, M-theory, and F-theory in the past 30
years.

</DOC>
<DOC>
<DOCNO> 71980 </DOCNO>
Charged spin 1/2 particle in an arbitrary magnetic field in two spatial


  It is shown that the 2 X 2 matrix Hamiltonian describing the dynamics of a
charged spin 1/2 particle with g-factor 2 moving in an arbitrary, spatially
dependent, magnetic field in two spatial dimensions can be written as the
anticommuator of a nilpotent operator and its hermitian conjugate.
Consequently, the Hamiltonians for the two different spin projections form
partners of a supersymmetric quantum mechanical system. The resulting
supersymmetry algebra can then be exploited to explicitly construct the exact
zero energy ground state wavefunction for the system. Modulo this ground state,
the remainder of the eigenstates and eigenvalues of the two partner
Hamiltonians form positive energy degenerate pairs. We also construct the
spatially asymptotic form of the magnetic field which produces a finite
magnetic flux and associated zero energy normalizable ground state
wavefunction.

</DOC>
<DOC>
<DOCNO> 9142 </DOCNO>
Static and dynamic spin correlations in the spin-glass phase of


  Neutron scattering experiments reveal that a diagonal spin modulation, which
is a one-dimensional modulation rotated away by 45$^\circ$ from that in the
superconducting phase, occurs universally across the insulating spin-glass
phase in La$_{2-x}$Sr$_x$CuO$_4$ (0.02$\le x\le$0.055). This establishes an
intimate relation between the magnetism and the transport properties in the
high-temperature copper oxide superconductors. Furthermore, it is found that
the charge density per unit length estimated using a charge stripe model is
almost constant throughout the phase diagram, even when the modulation rotates
away by 45$^\circ$ at the superconducting boundary. However, at the lowest
values for $x$ the density changes approaching 1 hole/Cu as in
La$_{2-x}$Sr$_x$NiO$_4$. Magnetic excitation spectra suggest that magnetic
correlations change from incommensurate to commensurate at $\omega\sim$7 meV
and $T\sim$70 K, indicating a characteristic energy for the incommensurate
structure of 6-7 meV.

</DOC>
<DOC>
<DOCNO> 80958 </DOCNO>
The Gribov Ambiguity for Maximal Abelian and Center Gauges in SU(2)


  We present results for the fundamental string tension in SU(2) lattice gauge
theory after projection to maximal abelian and direct maximal center gauges. We
generate 20 Gribov copies/configuration. Abelian and center projected string
tensions slowly decrease as higher values of the gauge functionals are reached.

</DOC>
<DOC>
<DOCNO> 13100 </DOCNO>
Unconventional superconductivity in CeIrIn$_5$ and CeCoIn$_5$: Specific


  Low temperature specific heat and thermal conductivity measurements on the
ambient pressure heavy fermion superconductors CeIrIn5 and CeCoIn5 reveal power
law temperature dependences of these quantities below T$_c$. The low
temperature specific heat in both CeIrIn5 and CeCoIn5 includes T$^2$ terms,
consistent with the presence of nodes in the superconducting energy gap. The
thermal conductivity data present a T-linear term consistent with the universal
limit (CeIrIn5), and a low temperature T$^3$ variation in the clean limit
(CeCoIn5), also in accord with prediction for an unconventional superconductor
with lines of nodes.

</DOC>
<DOC>
<DOCNO> 70967 </DOCNO>
Glueballs, hybrid and exotic mesons and string breaking


  We review lattice QCD results for glueballs (including a discussion of mixing
with scalar mesons), hybrid mesons and exotic mesons (such as $B_s B_s$
molecules). We also discuss string breaking as a mixing between colour flux
states and $B \bar{B}$ states.

</DOC>
<DOC>
<DOCNO> 67864 </DOCNO>
Quark-Antiquark Pairing Induced by Instantons in QCD


  The quark-antiquark pairing due to the four-fermion direct coupling induced
by the instantons in QCD is studied in the framework of the functional integral
method. The integral equations for the order parameters are derived. Several
classes of the solutions of these non-linear equations are considered in
details. Their implications for the dynamical symmetry breakings are discussed

</DOC>
<DOC>
<DOCNO> 11775 </DOCNO>
The anisotropic XY-model on the 1d alternating superlattice


  The anisotropic XY-model in a transverse field (s=1/2) on the one-dimensional
alternating superlattice (closed chain) is considered. The solution of the
model is obtained by introducing a generalized Jordan-Wigner transformation
which maps the system onto a non-interacting fermion gas. The exact excitation
spectrum is determined by reducing the problem to a diagonalization of a block
matrix, and it is shown that it is numerically identical to the one obtained by
using the approximate transfer matrix method . The induced magnetization and
the susceptibility $\chi ^{zz}$ are determined as a function of the transverse
field, and it is shown that, at T=0, the susceptibility presents multiple
singularities. It is also shown, as expected, that this critical behaviour
driven by transverse field belongs to the same universality class of the model
on the alternating chain.

</DOC>
<DOC>
<DOCNO> 10104 </DOCNO>
Electromagnetic Field Correlation inside a Sonoluminescing Bubble


  We consider the correlation of the electromagnetic field to determine spatial
coherence inside a sonoluminescing bubble. We explicitly calculate the first
order correlation function for two limiting cases of the excitation field: a
blackbody spectrum and a discrete multifrequency spectrum. The correlation
length for blackbody fields at temperatures between 3000 K and 10000 K is found
to be on the order of the optical wavelength, increasing with decreasing
temperatures. We predict spectral lines in the emission spectrum of single
bubble sonoluminescence in cooler bubbles with interior temperatures below
10000 K.

</DOC>
<DOC>
<DOCNO> 68381 </DOCNO>
Status of Electroweak Phase Transition and Baryogenesis


  I review recent progress on the electroweak phase transition and
baryogenesis, focusing on the minimal supersymmetric standard model as the
source of new physics.

</DOC>
<DOC>
<DOCNO> 116730 </DOCNO>
Improved efficiency with variational Monte Carlo using two level


  A two level sampling method is applied to variational Monte Carlo (VMC) that
samples the one and two body parts of the wave function separately. The method
is demonstrated on a single Li_2 molecule in free space and 32 H_2 molecules in
a periodic box. This simple modification increases the efficiency of a VMC
simulation by up to 72%.

</DOC>
<DOC>
<DOCNO> 116341 </DOCNO>
Post acceleraed Frames


  Special relativistic effects occur only on post accelerated frames, which are
frames, which were accelerated in the past to reach a certain uniform velocity
before the measurement of these effects. A symmetry breaking in special
relativity is then obtained. The non-symmetrical equations for space time,
length and charge density are presented.

</DOC>
<DOC>
<DOCNO> 40066 </DOCNO>
New Clock Comparison Searches for Lorentz and CPT Violation


  We present two new measurements constraining Lorentz and CPT violation using
the Xe-129 / He-3 Zeeman maser and atomic hydrogen masers. Experimental
investigations of Lorentz and CPT symmetry provide important tests of the
framework of the standard model of particle physics and theories of gravity.
The two-species Xe-129 / He-3 Zeeman maser bounds violations of CPT and Lorentz
symmetry of the neutron at the 10^-31 GeV level. Measurements with atomic
hydrogen masers provide a clean limit of CPT and Lorentz symmetry violation of
the proton at the 10^-27 GeV level.

</DOC>
<DOC>
<DOCNO> 80892 </DOCNO>
Vortices and bags in 2+1 dimension


  We consider the effect of the (heavy) fundamental quarks on the low energy
effective Lagrangian description of nonabelian gauge theories in 2+1
dimensions. We show that in the presence of the fundamental charges, the
magnetic $Z_N$ symmetry becomes local. We construct the effective Lagrangian
representing this local symmetry in terms of magnetic vortex fields, and
discuss its physical consequences. We show that the finite energy states
described by this Lagrangian have distinct bag-like structure. The point-like
quarks are confined to the region of space where the value of the vortex field
is much smaller than in the surrounding vacuum.

</DOC>
<DOC>
<DOCNO> 84830 </DOCNO>
Detection of gravitational waves with quantum encryption technology


  We propose a new technique for detecting gravitational waves using Quantum
Entangled STate (QUEST) technology. Gravitational waves reduce the non-locality
of correlated quanta controlled by Bell's inequalities, distorting quantum
encryption key statistics away from a pure white noise. Gravitational waves
therefore act as shadow eavesdroppers. The resulting colour distortions can, at
least in principle, be separated from noise and can differentiate both
deterministic and stochastic sources.

</DOC>
<DOC>
<DOCNO> 169579 </DOCNO>
Is Supersymmetric Quantum Mechanics compatible with Duality


  Supersymmetry applied to quantum mechanics has given new insights in various
topics of theoretical physics like analytically solvable potentials, WKB
approximation or KdV solitons. Duality plays a central role in many
supersymmetric theories such as Yang-Mills theories or strings models. We
investigate the possible existence of some duality within supersymmetric
quantum mechanics.

</DOC>
<DOC>
<DOCNO> 12724 </DOCNO>
Ab initio determination of an extended Heisenberg Hamiltonian in CuO2


  Accurate ab initio calculations on embedded Cu_4O_{12} square clusters,
fragments of the La_2CuO_4 lattice, confirm a value of the nearest neighbor
antiferromagnetic coupling (J=124 meV) previously obtained from ab initio
calculations on bicentric clusters and in good agreement with experiment. These
calculations predict non negligible antiferromagnetic second-neighbor
interaction (J'=6.5 meV) and four-spin cyclic exchange (K=14 meV), which may
affect the thermodynamic and spectroscopic properties of these materials. The
dependence of the magnetic coupling on local lattice distortions has also been
investigated. Among them the best candidate to induce a spin-phonon effect
seems to be the movement of the Cu atoms, changing the Cu-Cu distance, for
which the variation of the nearest neighbor magnetic coupling with the Cu-O
distance is {\Delta J}/{\Delta d_{Cu-O}}\sim 1700 cm^{-1} A^{-1}.

</DOC>
<DOC>
<DOCNO> 178608 </DOCNO>
Generalized Faddeev Equations for N-Particle Scattering


  A proposal is made for reducing the solution of the N-particle
Lippmann-Schwinger equation to that of smaller sets of particles. This consists
of first writing the N-particle equation in terms of all possible
$N/2$-particle Lippmann-Schwinger equations. (If N is odd this needs a minor
modification.) The second step requires a decoupling of the resolvents for the
fewer particle systems so that each can be solved separately. This
generalization of the Faddeev approach deals only with connected kernels and
the homogeneous solution reproduces the N-particle Schr\"odinger equation.
For four particles the proposed method involves only a $3\times3$ matrix
whereas other approaches typically require the solution of at least a
$7\times7$ matrix equation.

</DOC>
<DOC>
<DOCNO> 102179 </DOCNO>
Apollonian Circle Packings: Geometry and Group Theory III. Higher


  Apollonian circle packings arise by repeatedly filling the interstices
between four mutually tangent circles with further tangent circles. Such
packings can be specified in terms of the Descartes configurations they
contain, where an (ordered) Descartes configuration is an ordered set of four
mutually tangent circles having disjoint interiors, on the Riemann sphere.
Parts I and II considered groups of transformations preserving Apollonian
packings or the Descartes configurations in such packings. The paper considers
generalizations of these results to dimensions $n \geq 3$, for Apollonian
ensembles of $n$-dimensional Descartes configurations. These are no longer
packings for $n \geq 4,$ but there are analogues of most of the properties in
parts I and II for such ensembles of $n$-dimensional Descartes configurations.
An Apollonian sphere ensemble is strongly rational if every sphere in it has a
rational curvature and a rational center. We show that strongly rational
Apollonian sphere ensembles exist in dimension $n$ if and only if $n = 2k^2$ or
$n = (2k + 1)^2$ for some positive integer $k$.

</DOC>
<DOC>
<DOCNO> 116498 </DOCNO>
Superheated drop as a neutron spectrometer


  Superheated drops are known to vaporise when exposed to energetic nuclear
radiation since the discovery of bubble chamber. As the degree of superheat
increases in a given liquid, less and less energetic neutrons are required to
cause nucleation. This property of superheated liquids are being utilised to
develope the neutron spectromer. A new principle of neutron spectrometry using
Superheated liquid are developed and the developed principle has been tested by
Am-Be neutron source.

</DOC>
<DOC>
<DOCNO> 11397 </DOCNO>
Many-body theory of dilute gas condensates - derivation of a


  The Hamiltonian of a moving atom in electromagnetic fields includes velocity-
dependent terms. We show that the leading velocity dependence emerges
systematically in the non-relativistic limit from a scheme firmly based on the
relativistic invariance of the energy-momentum stress tensor of the coupled
matter-fields system. We then extend the Hamiltonian to the many-body situation
suitable for describing a Bose-Einstein condensate (BEC). From first
principles, we use the equation of motion for the condensate wavefunction to
obtain an extended version of the Gross-Pitaevskii (GP) equation and an
equation for the internal states of the atoms. It is shown that laser fields
modify the GP equation by inclusion of convective terms involving a Rontgen
interaction plus a term coupling the centre of mass momentum to the Poynting
vector. We also obtain the modified Maxwell equations for the electromagnetic
fields coupled to the BEC involving the average velocity of the atoms.

</DOC>
<DOC>
<DOCNO> 120203 </DOCNO>
Solar cycle induced variations in GONG p-mode frequencies and splittings


  We have analysed the recently available GONG p-mode frequencies and splitting
coefficients for a period of three and half years, including the rapidly rising
phase of solar cycle 23. The analysis of mean frequency shift with different
activity indices shows that the shift is equally correlated with both magnetic
and radiative indices. During the onset of the new cycle 23, we notice that the
change in $b_4$ splitting coefficient is more prominent than the change in
$b_2$. We have estimated the solar rotation rate with varying depth and
latitude. In the equatorial region, the rotation first increases with depth and
then decreases, while an opposite behaviour is seen in the polar region. We
also find a small but significant temporal variation in the rotation rate at
high latitudes.

</DOC>
<DOC>
<DOCNO> 11934 </DOCNO>
Quasi-sparse eigenvector diagonalization and stochastic error correction


  We briefly review the diagonalization of quantum Hamiltonians using the
quasi-sparse eigenvector (QSE) method. We also introduce the technique of
stochastic error correction, which systematically removes the truncation error
of the QSE result by stochastically sampling the contribution of the remaining
basis states.

</DOC>
<DOC>
<DOCNO> 70424 </DOCNO>
Branching processes and Koenigs function


  An explicit solution of non-critical time-homogeneous branching processes is
described.

</DOC>
<DOC>
<DOCNO> 8414 </DOCNO>
The Ground State Energy of a Dilute Two-dimensional Bose Gas


  The ground state energy per particle of a dilute, homogeneous,
two-dimensional Bose gas, in the thermodynamic limit is shown rigorously to be
$E_0/N = (2\pi \hbar^2\rho /m){|\ln (\rho a^2)|^{-1}}$, to leading order, with
a relative error at most ${\rm O} (|\ln (\rho a^2)|^{-1/5})$. Here $N$ is the
number of particles, $\rho =N/V$ is the particle density and $a$ is the
scattering length of the two-body potential. We assume that the two-body
potential is short range and nonnegative. The amusing feature of this result is
that, in contrast to the three-dimensional case, the energy, $E_0$ is not
simply $N(N-1)/2$ times the energy of two particles in a large box of volume
(area, really) $V$. It is much larger.

</DOC>
<DOC>
<DOCNO> 99793 </DOCNO>
Formal biholomorphic maps of real analytic hypersurfaces


  Let f : (M,p)\to (M',p') be a formal biholomorphic mapping between two germs
of real analytic hypersurfaces in \C^n, p'=f(p). Assuming the source manifold
to be minimal at p, we prove the convergence of the so-called reflection
function associated to f. As a consequence, we derive the convergence of formal
biholomorphisms between real analytic minimal holomorphically nondegenerate
hypersurfaces. Related results on partial convergence of formal biholomorphisms
are also obtained.

</DOC>
<DOC>
<DOCNO> 8636 </DOCNO>
Many-body CPA for the Holstein-DE model


  A many-body coherent potential approximation (CPA) previously developed for
the double exchange (DE) model is extended to include coupling to local quantum
phonons. The Holstein-DE model studied (equal to the Holstein model for zero
Hund coupling) is considered to be a simple model for the colossal
magnetoresistance manganites. We concentrate on effects due to the quantisation
of the phonons, such as the formation of polaron subbands. The electronic
spectrum and resistivity are investigated for a range of temperature and
electron-phonon coupling strengths. Good agreement with experiment is found for
the Curie temperature and resistivity with intermediate electron-phonon
coupling strength, but phonon quantisation is found not to have a significant
effect in this coupling regime.

</DOC>
<DOC>
<DOCNO> 71321 </DOCNO>
The Two-Component Non-Perturbative Pomeron and the G-Universality


  In this communication we present a generalization of the Donnachie-Landshoff
model inspired by the recent discovery of a 2-component Pomeron in LLA-QCD by
Bartels, Lipatov and Vacca. In particular, we explore a new property, not
present in the usual Regge theory - the G-Universality - which signifies the
independence of one of the Pomeron components on the nature of the initial and
final hadrons. The best description of all the forward hadron-hadron, gamma-
gamma and gamma-proton data is obtained when G-universailty is imposed.
Moreover, the maximal (ln)**2 behaviour of the hadron amplitude, first
established by Heisenberg, is clearly favoured by the data.

</DOC>
<DOC>
<DOCNO> 40551 </DOCNO>
Measurements of the Cross Sections for Open Charm and Beauty Production


  The production of c and b quarks in gamma-gamma collisions is studied with
the L3 detector at LEP with 410 pb^-1 of data, collected at centre-of-mass
energies from 189 GeV to 202 GeV. Hadronic final states containing c and b
quarks are identified by detecting electrons or muons from their semileptonic
decays. The cross sections sigma(e+e- -> e+e- c c~ X) and sigma(e+e- -> e+e- b
b~ X) are measured and compared to next-to-leading order perturbative QCD
calculations. The cross section of b production is measured in gamma-gamma
collisions for the first time. It is in excess of the QCD prediction by a
factor of three.

</DOC>
<DOC>
<DOCNO> 99672 </DOCNO>
Quantization of Double Covers of Nilpotent Coadjoint Orbits I:


  We construct by geometric methods a noncommutative model E of the algebra of
regular functions on the universal (2-fold) cover M of certain nilpotent
coadjoint orbits O for a complex simple Lie algebra g. Here O is the dense
orbit in the cotangent bundle of the generalized flag variety X associated to a
complexified Cartan decomposition g=(p^+)+k+(p^-) where p^+- are Jordan
algebras by the TKK construction.
  We obtain E as the algebra of g-finite differential operators on a smooth
Lagrangian subvariety in M where g is given by differential operators twisted
according to a critical parameter. After Fourier transform, E is a quadratic
extension of the algebra of twisted differential operators for a (formal)
tensor power of the canonical bundle.
  Not only is E a Dixmier algebra for M, in the sense of the orbit method, but
also E has a lot of additional structure,including an anti-automorphism, a
supertrace, and a non-degenerate supersymmetric bilinear pairing. We show that
E is the specialization at t=1 of a graded (non-local) equivariant star product
with parity.

</DOC>
<DOC>
<DOCNO> 13589 </DOCNO>
Analytical Hartree-Fock gradients for periodic systems


  We present the theory of analytical Hartree-Fock gradients for periodic
systems as implemented in the code CRYSTAL. We demonstrate how derivatives of
the integrals can be computed with the McMurchie-Davidson algorithm. Highly
accurate gradients with respect to nuclear coordinates are obtained for systems
periodic in 0,1,2 or 3 dimensions.

</DOC>
<DOC>
<DOCNO> 11885 </DOCNO>
Large Scale Simulations of Two-Species Annihilation, A+B->0, with Drift


  We present results of computer simulations of the diffusion-limited reaction
process A+B->0, on the line, under extreme drift conditions, for lattices of up
to 2^{27} sites, and where the process proceeds to completion (no particles
left). These enormous simulations are made possible by the renormalized
reaction-cell method (RRC). Our results allow us to resolve an existing
controversy about the rate of growth of domain sizes, and about corrections to
scaling of the concentration decay.

</DOC>
<DOC>
<DOCNO> 116965 </DOCNO>
Observation of a H- Beam Ion Instability


  We report the results of observations of H- beam instabilities at the
Fermilab Linac. By intentionally creating "high" background pressure with
different gases in the 750 keV transport line we observed coherent transverse
beam oscillations. The minimal pulse length required to observe oscillations
and the frequency of oscillations are functions of pressure and mass of the
background gas. The oscillations are present in both transverse planes and very
quickly reach saturation in amplitude growth. The observed characteristics of
beam oscillations are in quantitative agreement with "fast beam-ion
instability" described by Raubenheimer and Zimmermann. Effects described here
are occur far from the normal operating range of the Fermilab Linac but may be
important for many future high intensity accelerators.

</DOC>
<DOC>
<DOCNO> 39989 </DOCNO>
Parton Scattering at Small-x and Scaling Violation


  Scaling violation of inclusive jet production at small-$x$ in hadron
scattering with increasing total collision energy is discussed. Perturbative
QCD based on the factorisation theorem for hard processes and GLAPD evolution
equations predicts a minimum for scaled cross-section ratio that depends on jet
rapidity. Studies of such a scaling violation can reveal a vivid indication of
new dynamical effects in the high-energy limit of QCD. The BFKL effects, which
seem to be seen in recent L3 data at CERN LEP2, should give different results
from GLAPD predictions.

</DOC>
<DOC>
<DOCNO> 13201 </DOCNO>
Mesoscopic fluctuations of the Coulomb drag at $\nu$=1/2


  We consider mesoscopic fluctuations of Coulomb drag transresistivity between
two layers at a Landau level filling factor $\nu=1/2$ each. We find that at low
temperature sample to sample fluctuations exceed both the ensemble average and
the corresponding fluctuations at B=0. At the experimentally relevant
temperatures, the variance of the transresistivity is proportional to
$T^{-1/2}$. We find the dependence of this variance on density and magnetic
field to reflect the attachment of two flux quanta to each electron.

</DOC>
<DOC>
<DOCNO> 40169 </DOCNO>
Search for anomalous couplings in the Higgs sector at LEP


  We search for a Higgs particle with anomalous couplings in the e+e- -> H
gamma, e+e- -> HZ and e+e- -> He+e- processes with the L3 detector at LEP. We
explore the mass range 70GeV < m_H < 170GeV using 176pb^-1 of integrated
luminosity at a center-of-mass energy of \sqrt{s} = 189GeV. The Higgs decays H
-> bb, H -> gamma gamma and H -> Z gamma are considered in the analysis. No
evidence for anomalous Higgs production is found. This is interpreted in terms
of limits on the anomalous couplings d, d_B, Delta g_1^Z and Delta kappa_gamma.
Limits on the Gamma(H -> gamma gamma) and Gamma(H -> Z gamma) partial widths in
the explored Higgs mass range are also obtained.

</DOC>
<DOC>
<DOCNO> 68970 </DOCNO>
Non-perturbative gluodynamics of high energy heavy-ion collisions


  The dynamics of low-x partons in the transverse plane of a high-energy
nuclear collision is classical, and therefore admits a fully non--perturbative
numerical treatment. We report results of a recent study estimating the initial
energy density in the central region of a collision. Preliminary estimates of
the number of gluons per unit rapidity, and the initial transverse momentum
distribution of gluons, are also provided.

</DOC>
<DOC>
<DOCNO> 118578 </DOCNO>
Kilohertz quasi-periodic oscillations in low mass X-ray binary sources


  Starting from the observation that kilohertz Quasi Period Oscillations (kHz
QPO) occur in a very narrow range of X-ray luminosities in neutron star low
mass X-ray binaries, we try to link the kHz QPO observability to variations of
the neutron star magnetospheric radius, in response to changing mass inflow
rate. At low luminosities, the drop off of kHz QPOs activity may be explained
by the onset of the centrifugal barrier, when the magnetospheric radius reaches
the corotation radius. At the opposite side, at higher luminosities, the
magnetospheric radius may reach the neutron star and the vanishing of the
magnetosphere may led to the stopping of the kHz QPOs activity. If we apply
these constraints, the magnetic fields of atoll (B ~ 0.3-1 10^8 G for Aql X-1)
and Z (B ~ 1-8 10^8 G for Cyg X-2) sources can be derived. These limits
naturally apply in the framework of beat frequency models but can also work in
the case of general relativistic models.

</DOC>
<DOC>
<DOCNO> 116598 </DOCNO>
Lagrangian Approaches of Dirac and Feynman to Quantum Mechanics


  Lagrangian method in quantum mechanics is discussed in a pedagogical context.
It is pointed out that introduction of the action principle into the quantum
theory is much in the way of a formal correspondence. A general formulation of
the action principle is outlined, embodying the main features of Dirac's and
Feynman's approaches to quantum mechanics. This review is carried to a point
further than that reached by these authors, in the discussion of the action
principle and correspondence. Judged by a criterion of correspondence arguments
energy levels of harmonic oscillator must be $E_n=n\hbar\omega$ instead of
being $E_n=(n+1/2)\hbar\omega$.

</DOC>
<DOC>
<DOCNO> 100424 </DOCNO>
Multiple zeta-values, Galois groups, and geometry of modular varieties


  We discuss the following two problems: 1) The properties of the multiple
zeta-values and their generalizations, multiple polylogarithms at N-th roots of
unity; 2) The action of the absolute Galois group on the pro-l-completion of
the fundamental group of the projective line without zero, infinity, and all
N-th roots of unity; and a surprising connection of these problems with the
geometry and topology of modular varieties for GL_m.

</DOC>
<DOC>
<DOCNO> 13215 </DOCNO>
The Condensed Matter Physics of QCD


  Important progress in understanding the behavior of hadronic matter at high
density has been achieved recently, by adapting the techniques of condensed
matter theory. At asymptotic densities, the combination of asymptotic freedom
and BCS theory make a rigorous analysis possible. New phases of matter with
remarkable properties are predicted. They provide a theoretical laboratory
within which chiral symmetry breaking and confinement can be studied at weak
coupling. They may also play a role in the description of neutron star
interiors. We discuss the phase diagram of QCD as a function of temperature and
density, and close with a look at possible astrophysical signatures.

</DOC>
<DOC>
<DOCNO> 170533 </DOCNO>
Cartan Decomposition of SU(2^n), Constructive Controllability of Spin


  In this paper we provide an explicit parameterization of arbitrary unitary
transformation acting on n qubits, in terms of one and two qubit quantum gates.
The construction is based on successive Cartan decompositions of the
semi-simple Lie group, SU(2^n). The decomposition highlights the geometric
aspects of building an arbitrary unitary transformation out of quantum gates
and makes explicit the choice of pulse sequences for the implementation of
arbitrary unitary transformation on $n coupled spins. Finally we make
observations on the optimality of the design procedure.

</DOC>
<DOC>
<DOCNO> 117993 </DOCNO>
Neutrino Afterglows and Progenitors of Gamma-Ray Bursts


  Currently popular models for progenitors of gamma-ray bursts (GRBs) are the
mergers of compact objects and the explosions of massive stars. These two cases
have distinctive environments for GRBs: compact object mergers occur in the
interstellar medium (ISM) and the explosions of massive stars occur in the
preburst stellar wind. We here discuss neutrino afterglows from reverse shocks
as a result of the interaction of relativistic fireballs with their surrounding
wind matter. After comparing with the analytical result of Waxman & Bahcall
(2000) for the homogeneous ISM case, we find that the differential spectrum of
neutrinos with energy from $\sim 3\times 10^{15}$ to $\sim 3\times 10^{17}$ eV
in the wind case is softer by one power of the energy than in the ISM case.
Furthermore, the expected flux of upward moving muons produced by neutrino
interactions below a detector on the surface of the Earth in the wind case is
$\sim 5$ events per year per km$^2$, which is about one order of magnitude
larger than in the ISM case. In addition, these properties are independent of
whether the fireballs are isotropic or beamed. Therefore, neutrino afterglows,
if detected, may provide a way of distinguishing between GRB progenitor models
based on the differential spectra of neutrinos and their event rates in a
detector.

</DOC>
<DOC>
<DOCNO> 122207 </DOCNO>
Modelling the spin pulse profile of the isolated neutron star RX


  We model the spin pulse intensity and hardness ratio profiles of the isolated
neutron star RXJ0720.4--3125 using XMM-Newton data. The observed variation is
approximately sinusoidal with a peak-to-peak amplitude of 15%, and the hardness
ratio is softest slightly before flux maximum. By using polar cap models we are
able to derive maximum polar cap sizes and acceptable viewing geometries. The
inferred sizes of the caps turn out to be more compatible with a scenario in
which the neutron star is heated by accretion, and place limits on the magnetic
field strength. The hardness ratio modulation can then be explained in terms of
energy-dependent beaming effects, and this constrains the acceptable models of
the emerging radiation to cases in which softer photons are more strongly
beamed than harder photons. An alternative explanation in terms of spatially
variable absorption co-rotating in the magnetosphere is also discussed.

</DOC>
<DOC>
<DOCNO> 69768 </DOCNO>
The nucleon spin structure in a simple quark model


  We investigate the spin structure of the nucleon in an extended Jaffe-Lipkin
quark model. In addition to the conventional $3q$ structure, different
$(3q)(Q\bar{Q})$ admixtures in the nucleon wavefunction are also taken into
account. The contributions to the nucleon spin from various components of the
nucleon wavefunction are discussed. The effect due to the Melosh-Wigner
rotation is also studied.

</DOC>
<DOC>
<DOCNO> 151141 </DOCNO>
Particle masses and the fifth dimension


  We solve a Dirac-like equation laid in five dimensions with a self-force
dependent on the fifth coordinate for the mass eigenstates of generic spin 1/2
fermions. The enlargement of space-time to five dimensions is forced and the
form of this equation is uniquely fixed if the present symmetry group of
space-time is enlarged from the Poincare group to the conformal group. The mass
spectrum consists of a few points with non-uniform spacing. Masses for the
isospin-down quarks d, s, and b of the right order of magnitude are predicted
for reasonable values of the parameters. Some consequences for the quantum
field theory based on this five-dimensional geometry are explored.

</DOC>
<DOC>
<DOCNO> 80937 </DOCNO>
Moments of Structure Functions in Full QCD


  Moments of the quark density distribution, moments of the quark helicity
distribution, and the tensor charge are calculated in full QCD. Calculations of
matrix elements of operators from the operator product expansion have been
performed on $16^3 \times 32$ lattices for Wilson fermions at $\beta = 5.6$
using configurations from the SESAM collaboration and at $\beta = 5.5$ using
configurations from SCRI. One-loop perturbative renormalization corrections are
included. Selected results are compared with corresponding quenched
calculations and with calculations using cooled configurations.

</DOC>
<DOC>
<DOCNO> 101977 </DOCNO>
A Set of Sequences in Number Theory


  74 new integer sequences are introduced in number theory, and for each of
them is given a characterization, followed by open problems. each one a general
question: how many primes each sequence has.

</DOC>
<DOC>
<DOCNO> 39833 </DOCNO>
Bottom Quark Physics - Past, Present, Future


  On the occasion of a symposium honoring my collegue Adrian Melissinos, I gave
an informal, personal review of bottom quark physics. This paper is a writeup
of that talk. I first summarize the early days, the decade from the discovery
through the determination of the b quark's rough features. I note a change in
objective which occurred around 1990, with the new emphasis being USING the b
quark, to probe the Standard Model and to search for physics `beyond the
Standard Model'. I review the flavor sector of the Standard Model, showing why
the b quark is such a useful probe. I then discuss three topics of current
interest: the determination of V_ub; studies of rare hadronic B decays; and the
radiative penguin decay b -> s gamma.

</DOC>
<DOC>
<DOCNO> 117830 </DOCNO>
On the Existence of Differences in Luminosity between Horizontal Branch


  The discrepancy between a LONG distance scale derived from Hipparcos based
distances to globular clusters via main sequence fitting to local subdwarfs,
and a SHORT distance scale derived from the absolute magnitude of field RR
Lyraes via statistical parallaxes and the Baade-Wesselink method could be
accounted for whether an intrinsic difference of about 0.1-0.2 mag was found to
exist between horizontal branch (HB) stars populating the "sparse" general
field and the "dense" globular clusters. In this paper we discuss the possible
existence of such a systematic difference comparing the "period-shifts"
observed for field and cluster RR Lyraes. Various approaches based on different
parameters and data-sets for both cluster and field variables were used in
order to establish the size of such a hypothetical difference, if any. We find
that on the whole very small not significant differences exist between the
period-metallicity distributions of field and cluster RR Lyraes, thus
confirming with a more quantitative approach, the qualitative conclusions by
Catelan (1998). This observational evidence translates into a very small
difference between the horizontal branch luminosity of field and cluster stars,
unless RR Lyraes in Globular Clusters are about 0.06 Mo more massive than field
RR Lyrae at same metallicity, which is to be proven.

</DOC>
<DOC>
<DOCNO> 40053 </DOCNO>
Light response of pure CsI calorimeter crystals painted with


  We have measured scintillation properties of pure CsI crystals used in the
shower calorimeter built for a precise determination of the pi+ -> pi0 e+ nu
decay rate at the Paul Scherrer Institute (PSI). All 240 individual crystals
painted with a special wavelength-shifting solution were examined in a
custom-build detection apparatus (RASTA=radioactive source tomography
apparatus) that uses a 137Cs radioactive gamma source, cosmic muons and a light
emitting diode as complementary probes of the scintillator light response. We
have extracted the total light output, axial light collection nonuniformities
and timing responses of the individual CsI crystals. These results predict
improved performance of the 3 pi sr PIBETA calorimeter due to the painted
lateral surfaces of 240 CsI crystals. The wavelength-shifting paint treatment
did not affect appreciably the total light output and timing resolution of our
crystal sample. The predicted energy resolution for positrons and photons in
the energy range of 10-100 MeV was nevertheless improved due to the more
favorable axial light collection probability variation. We have compared
simulated calorimeter ADC spectra due to 70 MeV positrons and photons with a
Monte Carlo calculation of an ideal detector light response.

</DOC>
<DOC>
<DOCNO> 85460 </DOCNO>
Search for Periodic Gravitational Wave Sources with the Explorer


  We have developped a procedure for the search of periodic signals in the data
of gravitational wave detectors. We report here the analysis of one year of
data from the resonant detector Explorer, searching for pulsars located in the
Galactic Center (GC). No signals with amplitude greater than $\bar{h}=
2.9~10^{-24}$, in the range 921.32-921.38 Hz, were observed using data
collected over a time period of 95.7 days, for a source located at
$\alpha=17.70 \pm 0.01$ hours and $\delta=-29.00 \pm 0.05$ degrees. Our
procedure can be extended for any assumed position in the sky and for a more
general all-sky search, even with a frequency correction at the source due to
the spin-down and Doppler effects.

</DOC>
<DOC>
<DOCNO> 70062 </DOCNO>
Global Characteristics of Nucleus-Nucleus Collisions in an


  The global observable distributions of nucleus-nucleus collisions at high
energy are studied. It is shown that these distributions are sensitive to
interaction dynamics and can be used to investigate the evolution of dense
nuclear matter. At the LHC energy scale ($\sqrt{s_{NN}}=5$ TeV in the heavy ion
mode), a central bump over pseudorapidity plateau in the differential
distributions of total transverse energy flows induced by the jet quenching
effect was obtained. The energy-loss dependence on the energy for various
colliding ion species was explored. Also a new scheme for collision geometry
determination is proposed as well. It is based on the correlation between
transverse energy flow in the pseudorapidity interval $3<|\eta|<5$ and an
impact parameter.

</DOC>
<DOC>
<DOCNO> 68787 </DOCNO>
Polarised parton densities from the fits to the deep inelastic spin


  We have made next to leading order QCD fit to the deep inelastic spin
asymmetries on nucleons and we have determined polarised quark and gluon
densities. The functional form for such distributions was inspired by the
unpolarised ones given by MRST (Martin, Roberts, Stirling and Thorne) fit. In
addition to usually used data points (averaged over $Q^2$) we have also
considered the sample containing points with the same $x$ and different $Q^2$.
Our fits to both groups of data give very similar results. For the integrated
quantities we get rather small gluon polarisation. For the non averaged data
the best fit is obtained with vanishing gluon contribution at $ Q^{2}=1 {\rm
GeV^{2}}$. For comparison models with alternative assumptions about quark sea
and in particular strange sea behaviour are discussed.

</DOC>
<DOC>
<DOCNO> 69095 </DOCNO>
Recent results on Charm Physics from Fermilab


  New high statistics, high resolution fixed target experiments producing
$10^5$ - $10^6$ fully reconstructed charm particles are allowing a detailed
study of the charm sector. Recent results on charm quark production from
Fermilab fixed target experiments E791, SELEX and FOCUS are presented.

</DOC>
<DOC>
<DOCNO> 170772 </DOCNO>
Comment on "Proposal for the Measurement of Bell-Type Correlations from


  In a recent paper [T. C. Ralph, W. J. Munro, R. E. S. Polkinghorne, Phys.
Rev. Lett. 85, 2035 (2000)], the authors propose a test for Bell's inequalities
based on quadrature measurements for a correlated parametric source. We present
here a local hidden variable model which reproduces all the expectation values
predicted in the described experimental scheme, and point out that the proposal
is based on an inconsistent use of Bell's inequalities.

</DOC>
<DOC>
<DOCNO> 83225 </DOCNO>
Finite-State Reduplication in One-Level Prosodic Morphology


  Reduplication, a central instance of prosodic morphology, is particularly
challenging for state-of-the-art computational morphology, since it involves
copying of some part of a phonological string. In this paper I advocate a
finite-state method that combines enriched lexical representations via
intersection to implement the copying. The proposal includes a
resource-conscious variant of automata and can benefit from the existence of
lazy algorithms. Finally, the implementation of a complex case from Koasati is
presented.

</DOC>
<DOC>
<DOCNO> 68760 </DOCNO>
On the derivation of the neutrino oscillation length formula


  Forsaking the traditionnal hand-waving in the treatment of the motion, we
show that the ultra-relativistic approximation and the equality of kinematical
variables are unnecessary ingredients in the derivation of the oscillation
length using plane waves, at least in a two flavor world. It ensues that the
formula is valid as it is in the non relativistic regime, provided one uses the
correct variable which is found to be momentum, not energy, and that the
precise production kinematics is irrelevant. Consequences for the more complete
treatments are briefly evoked.

</DOC>
<DOC>
<DOCNO> 70054 </DOCNO>
HIJING Model Prediction on Squeeze-Out of Particles in Nucleus-Nucleus


  Elliptic flow of hard partons (P>5 GeV), squeeze-out of soft partons (P<=5
GeV) and produced particles are predicted in the framework of the HIJING model.
They are caused due to jet quenching and heterogeneity of the interaction
region.

</DOC>
<DOC>
<DOCNO> 151720 </DOCNO>
Domain walls in five dimensional supergravity with non-trivial


  We study BPS domain wall solutions of 5-dimensional N=2 supergravity where
isometries of the hypermultiplet geometry have been gauged. We derive the
corresponding supersymmetric flow equations and define an appropriate
c-function. As an example we discuss a domain wall solution of Freedman,
Gubser, Pilch and Warner which is related to a RG-flow in a dual superconformal
field theory.

</DOC>
<DOC>
<DOCNO> 170619 </DOCNO>
Comment on "Foundations of quantum mechanics: Connection with stochastic


  Recently, Olavo has proposed several derivations of the Schrodinger equation
from different sets of hypothesis ("axiomatizations") [Phys. Rev. A 61, 052109
(2000)]. One of them is based on the infinitesimal inverse Weyl transform of a
classically evolved phase space density. We show however that the Schrodinger
equation can only be obtained in that manner for linear or quadratic potential
functions.

</DOC>
<DOC>
<DOCNO> 10342 </DOCNO>
Quantum computation using electrons trapped by surface acoustic waves


  We describe in detail a set of ideas for implementing qubits, quantum gates
and quantum gate networks in a semiconductor heterostructure device. Our
proposal is based on an extension of the technology used for surface acoustic
wave (SAW) based single-electron transport devices. These devices allow single
electrons to be captured from a two-dimensional electron gas in the potential
minima of a SAW. We discuss how this technology can be adapted to allow the
capture of electrons in pure spin states and how both single and two-qubit
gates can be constructed using magnetic and non-magnetic gate technology. We
give designs for readout gates to allow the spin state of the electrons to be
measured and discuss how combinations of gates can be connected to make
multi-qubit networks. Finally we consider decoherence and other sources of
error, and how they can be minimized for our design.

</DOC>
<DOC>
<DOCNO> 69292 </DOCNO>
Using differential equations to compute two-loop box integrals


  The calculation of exclusive observables beyond the one-loop level requires
elaborate techniques for the computation of multi-leg two-loop integrals. We
discuss how the large number of different integrals appearing in actual
two-loop calculations can be reduced to a small number of master integrals. An
efficient method to compute these master integrals is to derive and solve
differential equations in the external invariants for them. As an application
of the differential equation method, we compute the ${\cal O}(\epsilon)$-term
of a particular combination of on-shell massless planar double box integrals,
which appears in the tensor reduction of $2 \to 2$ scattering amplitudes at two
loops.

</DOC>
<DOC>
<DOCNO> 68287 </DOCNO>
Neutrino Mixing and Maximal CP Violation


  We propose a phenomenological model of lepton mixing and CP violation based
on the flavor democracy of charge leptons and the mass degeneracy of neutrinos.
A nearly bi-maximal flavor mixing pattern, which is favored by current data on
atmospheric and solar neutrino oscillations, emerges naturally from this model
after explicit symmetry breaking. The rephasing-invariant strength of CP or T
violation can be as large as one percent, leading to significant probability
asymmetries between \nu_\mu \to \nu_e and \bar{\nu}_\mu \to \bar{\nu}_e (or
\nu_e \to \nu_\mu) transitions in the long-baseline neutrino experiments. The
possible matter effects on CP- and T-violating asymmetries are also taken into
account.

</DOC>
<DOC>
<DOCNO> 120218 </DOCNO>
First search for gravitational wave bursts with a network of detectors


  We report the initial results from a search for bursts of gravitational
radiation by a network of five cryogenic resonant detectors during 1997 and
1998. This is the first significant search with more than two detectors
observing simultaneously. No gravitational wave burst was detected. The false
alarm rate was lower than 1 per 10^4 years when three or more detectors were
operating simultaneously. The typical threshold was H ~ 4 10^-21 Hz^-1 on the
Fourier component at ~ 10^3 Hz of the gravitational wave strain amplitude. New
upper limits for amplitude and rate of g.w. bursts have been set.

</DOC>
<DOC>
<DOCNO> 80706 </DOCNO>
The Sigma Commutator from Lattice QCD


  As a direct source of information on chiral symmetry breaking within QCD, the
sigma commutator is of considerable importance. Since hadron structure is a
non-perturbative problem, numerical calculations on a space-time lattice are
currently the only rigorous approach. With recent advances in the calculation
of hadron masses within full QCD, it is of interest to see whether the sigma
commutator can be calculated directly from the dependence of the nucleon mass
on the input quark mass. We show that, provided the correct chiral behaviour of
QCD is respected in the extrapolation to realistic quark masses, one can indeed
obtain a fairly reliable determination of the sigma commutator using present
lattice data. For two-flavour dynamical fermion QCD the sigma commutator lies
between 45 and 55 MeV based on recent data from CP-PACS and UKQCD.

</DOC>
<DOC>
<DOCNO> 14157 </DOCNO>
Solitary waves and supersonic reaction front in metastable solids


  Motivated by an increasing number of remarkable experimental observations on
the role of pressure and shear stress in solid reactions,explosions and
detonations,we present a simple toy model that embodies nonlinear elasticity
and dispersion as well as chemical or phase transformation.This generalization
of the Toda Lattice provides an effective model for the description of the
organization during an abrupt transformation in a solid.One of the challenges
is to capture both the equilibrium degrees of freedom as well as to quantify
the possible role of out-of-equilibrium perturbations.In the Toda Lattice,we
verify that the particle velocities converge in distribution towards the
Maxwell-Boltzmann distribution,thus allowing us to define a bona-fide
temperature.In addition,the balance between nonlinearity and wave dispersion
may create solitary waves that act as energy traps.In the presence of reactive
chemistry,we show that the trapping of the released chemical energy in solitary
waves that are excited by an initial perturbation provides a positive feedback
that enhances the reaction rate and leads to supersonic explosion front
propagation.These modes of rupture observed in our model may provide a
first-order description of ultrafast reactions of heterogeneous mixtures under
mechanical loading.

</DOC>
<DOC>
<DOCNO> 10320 </DOCNO>
Vortices observed and to be observed


  Linear defects are generic in continuous media. In quantum systems they
appear as topological line defects which are associated with a circulating
persistent current. In relativistic quantum vacuum they are known as cosmic
strings, in superconductors as quantized flux lines, and in superfluids and
low-density atomic Bose-Einstein condensates as quantized vortex lines. We
discuss unconventional vortices in unconventional superfluids and
superconductors, which have been observed or have to be observed, such as
continuous singly and doubly quantized vortices in 3He-A and chiral Bose
condensates; half-quantum vortices (Alice strings) in 3He-A and in nonchiral
Bose condensates; Abrikosov vortices with fractional magnetic flux in chiral
and d-wave superconductors; vortex sheets in 3He-A and chiral superconductors;
the nexus -- combined object formed by vortices and monopoles. Some properties
of vortices related to fermionic quasiparticles living in the vortex core are
also discussed.

</DOC>
<DOC>
<DOCNO> 178523 </DOCNO>
Baryon distribution for high energy heavy ion collisions in a parton


  The baryon distribution is studied by using a parton cascade model which is
based on pQCD incorporating hard partonic scattering and dynamical
hadronization scheme. In order to study baryon distribution,baryonic cluster
formation is newly implemented as well as hadronic higher resonance states from
parton/beam cluster decay. The net baryon number and charged hadron
distributions are calculated with different $K$-factors in which parameters are
fixed by elementary $p\bar p$ data at $E_{c.m.}=200$ GeV. It is found that
baryon stopping behavior at SPS and RHIC energies are not consequence of hard
parton scattering but soft processes.

</DOC>
<DOC>
<DOCNO> 39940 </DOCNO>
Measurement of the Proton Structure Function F_2 at Very Low Q^2 at HERA


  A measurement of the proton structure function F_2(x,Q^2) is presented in the
kinematic range 0.045 GeV^2 < Q^2 < 0.65 GeV^2 and 6*10^{-7} < x < 1*10^{-3}.
The results were obtained using a data sample corresponding to an integrated
luminosity of 3.9pb^-1 in e^+p reactions recorded with the ZEUS detector at
HERA. Information from a silicon-strip tracking detector, installed in front of
the small electromagnetic calorimeter used to measure the energy of the
final-state positron at small scattering angles, together with an enhanced
simulation of the hadronic final state, has permitted the extension of the
kinematic range beyond that of previous measurements. The uncertainties in F_2
are typically less than 4%. At the low Q^2 values of the present measurement,
the rise of F_2 at low x is slower than observed in HERA data at higher Q^2 and
can be described by Regge theory with a constant logarithmic slope. The
dependence of F_2 on Q^2 is stronger than at higher Q^2 values, approaching, at
the lowest Q^2 values of this measurement, a region where F_2 becomes nearly
proportional to Q^2.

</DOC>
<DOC>
<DOCNO> 9954 </DOCNO>
Local magnetism of isolated Mo atoms at substitutional and interstitial


  Using TDPAD experiment and local spin density calculations, we have observed
large 4d moments on isolated Mo atoms at substitutional and octahedral
interstitial lattice sites in Yb metal, showing Curie-Weiss local
susceptibility and Korringa like spin relaxation rate. As a surprising feature,
despite strong hybridization with the Yb neighbours, interstitial Mo atoms show
high moment stability with small Kondo temperature. While, magnetism of Mo, at
substitutional site is consistent with Kondo type antiferromagnetic d-sp
exchange interaction, we suggest that moment stability at the interstitial site
is strongly influenced by ferromagnetic polarization of Yb-4f5d band electrons.

</DOC>
<DOC>
<DOCNO> 121127 </DOCNO>
Prospects for future far-infrared/submillimeter studies of the


  Observations made using COBE, SCUBA, ISO and MAMBO have provided a reasonable
working knowledge of both the intensity of the submm and far-infrared
background radiation and the source counts of luminous high-redshift dusty
galaxies. However, because there are uncertainties in the background intensity
determinations, the samples of detected galaxies are small, and most
importantly, their redshift distributions are very incomplete, details of the
evolution of dusty galaxies remain unresolved. The next steps forward in the
field will be the launches of SIRTF and ASTRO-F, the commissioning of SOFIA and
new, more capable ground-based mm/submm-wave cameras - BOLOCAM, SHARC-II and
SCUBA-II - the use of ultra-long duration balloon experiments, such as BLAST,
the construction of ALMA and the arrival of FIRST, and ultimately the advent of
space-borne far-infrared interferometers, such as SPECS. There are also
exciting prospects for direct mm/submm-wave CO-line redshift surveys using
wide-band spectrographs. Using these new facilities, the number of
high-redshift dusty galaxies known will be increased dramatically. Spectroscopy
using SIRTF, SOFIA and FIRST will probe the astrophysical processes within
these sources in detail, hopefully addressing the open question of the fraction
of the counts and background radiation that is generated by the formation of
high-mass stars and by active galactic nuclei (AGNs). The spatial and spectral
structure of distant dusty galaxies will finally be resolved in detail using
ALMA and SPECS.

</DOC>
<DOC>
<DOCNO> 70171 </DOCNO>
On the forward-backward correlations in a two-stage scenario


  It is demonstrated that in a two-stage scenario with elementary Poissonian
emitters of particles (colour strings) arbitrarily distributed in their number
and average multiplicities, the forward- backward correlations are completely
determined by the final distribution of the forward particles. The observed
linear form of the correlations then necessarily requires this distribution to
have a negative binomial form. For emitters with a negative binomial
distribution of the produced particles distributed so as to give the final
distribution also of a negative binomial form, the forward-backward
correlations have an essentially non-linear form, which disagrees with the
experimental data.

</DOC>
<DOC>
<DOCNO> 101322 </DOCNO>
Property C for ODE and applications


  An overview of the authors results is given. Property C for ODE is defioned,
It is proved that the pair of Sturm-Liouville operators has property C. This
property is applied to many inverse problems. Some well-known results, such as
uniqueness of the recovery of the potential from scattering data, from the
spectral function and from two spectra are proved in a new short way based on
property C. Many new results are obtained. In particular, it is proved that a
compactly supported potential can be uniquely recovered from the phase shift of
s-wave alone, known at all energies, without knowledge of bound states and
norming constants. The fixed-energy phase shifts known at some values of the
angular momentum determine a compactly supported potential uniquely. Mixed data
inverse problems are studied. Analysis of the Newton-Sabatier procedure is
given. It is shown that this procedure is a parameter-fitting procedure rather
than an inversion method. Other results on inverse problems are obtained.

</DOC>
<DOC>
<DOCNO> 116648 </DOCNO>
Estimating the K-function of a point process with an application to


  Motivated by the study of an important data set for understanding the
large-scale structure of the universe, this work considers the estimation of
the reduced second moment function, or K-function, of a stationary point
process observed over a large number of segments of possibly varying lengths.
Theory and simulation are used to compare the behavior of isotropic and rigid
motion correction estimators and some modifications of these estimators. These
results generally support the use of modified versions of the rigid motion
correction. When applied to a catalog of astronomical objects known as
absorbers, the proposed methods confirm results from earlier analyses of the
absorber catalog showing clear evidence of clustering up to 50 Mpc and marginal
evidence for clustering of matter on spatial scales beyond 100 Mpc, which is
beyond the distance at which clustering of matter is now generally accepted to
exist.

</DOC>
<DOC>
<DOCNO> 39895 </DOCNO>
Inclusive production of omega mesons at large transverse momenta in


  We present results on the production of omega mesons at high transverse
momenta in pi^-Be interactions at 515 GeV/c. The data span the kinematic range
3.5 < p_T < 8 GeV/c. We compare the measured cross section with expectations
from Monte Carlo QCD generators. The relative yield of omega to pi^0 mesons is
used to extract the ratio of vector to pseudoscalar meson production for the
first generation of quarks.

</DOC>
<DOC>
<DOCNO> 99556 </DOCNO>
On the approximation of the values of exponential function and logarithm


  A sharp explicit estimate is proved for the difference $e^\beta-\alpha$ when
$\alpha$ and $\beta$ are nonzero algebraic numbers.

</DOC>
<DOC>
<DOCNO> 119916 </DOCNO>
Some Musings on Globular Cluster Systems


  Globular cluster systems exhibit a bewildering variety of characteristics. No
single scenario appears to be able to account for the wide range of specific
globular cluster frequencies that are observed in galaxies of various types.
The fraction of all star formation that produces massive bound clusters differs
from galaxy to galaxy, and (in some cases) appears to vary with time. Presently
available data strongly suggest that the specific cluster forming frequency is
highest during violent bursts of star formation. Globular cluster systems show
a wide variety of color (metallicity) distributions, with many luminous
galaxies having double (or even multiple) metallicity peaks that were probably
produced during distinct episodes of cluster formation. The bulk of the
globulars in the main body of the Galactic halo appear to have formed during a
single short-lived burst that took place ~ 13 Gyr ago. This was followed by a
second, perhaps more extended, burst associated with the formation of the
Galactic bulge. A few metal-rich clusters may also be associated with the
formation of the Galactic Thick Disk. Finally many of the clusters beyond RGc ?
15 kpc might have been formed in dwarf spheroidal galaxies that, after a few
Gyr, were accreted by the main body of the Galactic halo. Some of these outer
clusters are younger, and less luminous, than the majority of globular clusters
formed at smaller Galactocentric distances.

</DOC>
<DOC>
<DOCNO> 151632 </DOCNO>
Nambu-Goldstone mechanism at finite temperature in the imaginary-time


  In the imaginay-time formalism of thermal field theory, and also in the
real-time formalism but by means of some redefined physical propagators for
scalar bound states by diagonalization of four-point function matrices, we
reexamine the Nambu-Goldstone mechanism of electroweak symmetry breaking in a
one-generation fermion condensate scheme, based on the Schwinger-Dyson equation
in the fermion bubble diagram approximation, and compare the obtained results.
We have reached the conclusion that in both the formalisms, the Goldstone
theorem of spontaneous electroweak symmetry breaking is rigorously true for the
case of mass-degenerate two flavors of fermions and only approximately valid at
low energy scales for the mass-nondegenerate case, in spite of existence of
some difference between the two formalisms in the imaginary parts of the
denominators of the propagators for scalar bound states. When the two flavors
of fermions have unequal nonzero masses, the induced possible fluctuation
effect for the Higgs particle is negligible if the momentum cut-off in the zero
temperature loops is large enough. All the results show physical equivalence of
the two formalisms in the present discussed problems.

</DOC>
<DOC>
<DOCNO> 13319 </DOCNO>
Quantum TAP equations


  We derive Thouless-Anderson-Palmer (TAP) equations for quantum disordered
systems. We apply them to the study of the paramagnetic and glassy phases in
the quantum version of the spherical p spin-glass model. We generalize several
useful quantities (complexity, threshold level, etc.) and various ideas
(configurational entropy crisis, etc), that have been developed within the
classical TAP approach, to quantum systems. The analysis of the quantum TAP
equations allows us to show that the phase diagram (temperature-quantum
parameter) of the p spin-glass model should be generic. In particular, we argue
that a crossover from a second order thermodynamic transition close to the
classical critical point to a first order thermodynamic transition close to the
quantum critical point is to be expected in a large class of systems.

</DOC>
<DOC>
<DOCNO> 121771 </DOCNO>
Infrared Spectra and Spectral Energy Distributions of Late-M- and


  We have obtained 1.0-2.5um spectra at R~600 of 14 disk dwarfs with spectral
types M6 to L7. For four of the dwarfs we have also obtained infrared spectra
at R~3000 in narrow intervals. In addition, we present new L' photometry for
four of the dwarfs in the sample, which allows improved determinations of their
bolometric luminosities. We resolve the L-dwarf Denis-P J 0205-1159 into an
identical pair of objects separated by 0.35". The spectra, with the published
energy distribution for one other dwarf, are compared to synthetic spectra
generated by upgraded model atmospheres. Good matches are found for 2200> Teff
K>1900 (spectral types around M9 to L3), but discrepancies exist at Teff> 2300
K (M8) and for Teff<1800 K (L4-L7). At the higher temperatures the mismatches
are due to incompleteness in the water vapor linelist. At the lower
temperatures the disagreement is probably due to our treatment of dust: we
assume a photospheric distribution in equilibrium with the gas phase. We derive
effective temperatures for the sample from the comparison with synthetic
spectra and also by comparing our observed total intrinsic luminosities to
structural model calculations (which are mostly independent of the atmosphere
but are dependent on the unknown masses and ages of the targets). The two
derivations agree to ~200 K except for the faintest object in the sample where
the discrepancy is larger. Agreement with other temperature determinations is
also ~200 K, except for the L7 dwarf.

</DOC>
<DOC>
<DOCNO> 40562 </DOCNO>
Measurement of open beauty production in photoproduction at HERA


  The production and semi-leptonic decay of heavy quarks have been studied in
the photoproduction process $e^+p -> e^+ + {dijet} + e^- + X with the ZEUS
detector at HERA using an integrated luminosity of 38.5 ${\rm pb^{-1}}$. Events
with photon-proton centre-of-mass energies, $W_{\gamma p}$, between 134 and 269
GeV and a photon virtuality, Q^2, less than 1 ${\rm GeV^2}$ were selected
requiring at least two jets of transverse energy $E_T^{\rm jet1(2)} >7(6)$ GeV
and an electron in the final state. The electrons were identified by employing
the ionisation energy loss measurement. The contribution of beauty quarks was
determined using the transverse momentum of the electron relative to the axis
of the closest jet, $p_T^{\rm rel}$. The data, after background subtraction,
were fit with a Monte Carlo simulation including beauty and charm decays. The
measured beauty cross section was extrapolated to the parton level with the b
quark restricted to the region of transverse momentum $p_T^{b} > p_T^{\rm min}
=$ 5 GeV and pseudorapidity $|\eta^{b}| <$ 2. The extrapolated cross section is
$1.6 \pm 0.4 (stat.)^{+0.3}_{-0.5} (syst.) ^{+0.2}_{-0.4} (ext.) {nb}$. The
result is compared to a perturbative QCD calculation performed to
next-to-leading order.

</DOC>
<DOC>
<DOCNO> 117590 </DOCNO>
High Resolution Rotation Curves of Low Surface Brightness Galaxies


  High resolution Halpha rotation curves are presented for five low surface
brightness galaxies. These Halpha rotation curves have shapes different from
those previously derived from HI observations, probably because of the higher
spatial resolution of the Halpha observations. The Halpha rotation curves rise
more steeply in the inner parts than the HI rotation curves and reach a flat
part beyond about two disk scale lengths. With radii expressed in optical disk
scale lengths, the rotation curves of the low surface brightness galaxies
presented here and those of HSB galaxies have almost identical shapes. Mass
modeling shows that the contribution of the stellar component to the rotation
curves may be scaled to explain most of the inner parts of the rotation curves,
albeit with high stellar mass-to-light ratios. On the other hand, well fitting
mass models can also be obtained with lower contributions of the stellar disk.
These observations suggest that the luminous mass density and the total mass
density are coupled in the inner parts of these galaxies.

</DOC>
<DOC>
<DOCNO> 85557 </DOCNO>
Episodic Self-Similarity in Critical Gravitational Collapse


  We report on a new behavior found in numerical simulations of spherically
symmetric gravitational collapse in self-gravitating SU(2) sigma models at
intermediate gravitational coupling constants: The critical solution (between
black hole formation and dispersion) closely approximates the continuously
self-similar (CSS) solution for a finite time interval, then departs from this,
and then returns to CSS again. This cycle repeats several times, each with a
different CSS accumulation point. We have preliminary evidence that this same
critical solution is also discretely self-similar (DSS) between the CSS
episodes, but with an echoing period $\Delta$ which varies during the
evolution.

</DOC>
<DOC>
<DOCNO> 99959 </DOCNO>
On Asymptotic Expansions and Scales of Spectral Universality in Band


  We consider the family of N-dimensional real symmetric matrices H with random
independent entries whose variance is determined by a function U((x-y)/b). In
the limit of (relatively) narrow band width 1<<b<<N, we obtain explicitly first
terms of 1/b-expansion of the resolvent of H. The expressions derived show that
the rate of decay of U(t) determines several scale of the universal form of the
eigenvalue correlation function. In particular, in the case of U(t) = o(1/t^3),
the Altshuller-Shklovski asymptotics with the ratio N/b^2 is obtained.

</DOC>
<DOC>
<DOCNO> 40566 </DOCNO>
Study of gamma gamma Background in e+e- -> W+W- nu nu -> H nu nu Events


  The effect of the overlap of gamma gamma -> hadrons to H nu nu events has
been studied for the case of the Tesla e+e- linear collider at 350 GeV. It was
found that, due to the significant bunch length and the track extrapolation
accuracy provided by the Vertex Tracker, the gamma gamma background to physics
events can be substantially reduced, with moderate loss in reconstruction
efficiency, by a combination of kinematical and vertex topology observables.
The remaining background, being confined to very forward hadron production,
does not significantly interfere with the event reconstruction.

</DOC>
<DOC>
<DOCNO> 121164 </DOCNO>
Pulsar Astronomy: the HST Contribution


  HST observations have contributed significantly to our knowledge on the
behaviour of Isolated Neutron Stars (INSs) as optical emitters. First, HST has
been instrumental both to discover new optical counterparts (PSR B1055-52, PSR
B1929+10, PSR B0950+08) and to confirm proposed identifications (PSR B0656+14).
Second, HST multicolor photometry provided useful information to characterize
the optical emission mechanism(s) at work in middle-aged INSs like PSR B0656+14
and Geminga. Last, but not least, the superior angular resolution of the HST
allowed both to perform a very accurate morphological study of the plerionic
environments of young pulsars (e.g. the Crab and PSR B0540-69) and to perform
very accurate astrometric measurements yielding proper motions (Crab, Vela,
Geminga, PSR B0656+14) and parallaxes (Geminga).

</DOC>
<DOC>
<DOCNO> 9738 </DOCNO>
Hidden Order in the Cuprates


  We propose that the enigmatic pseudogap phase of cuprate superconductors is
characterized by a hidden broken symmetry of d(x^2-y^2)-type. The transition to
this state is rounded by disorder, but in the limit that the disorder is made
sufficiently small, the pseudogap crossover should reveal itself to be such a
transition. The ordered state breaks time-reversal, translational, and
rotational symmetries, but it is invariant under the combination of any two. We
discuss these ideas in the context of ten specific experimental properties of
the cuprates, and make several predictions, including the existence of an
as-yet undetected metal-metal transition under the superconducting dome.

</DOC>
<DOC>
<DOCNO> 117460 </DOCNO>
Analysis and interpretation of the X-ray properties of black hole


  The thesis is mainly devoted to the study of spectral and timing
characteristics of the X-ray emission from Galactic black hole candidates GRS
1915+105, GX 339-4, 4U 1630-47, XTE J1748-288, GRS 1739-278, KS/GRS 1730-312
and GRS 1737-31. The main results include: observation of the correlated
evolution of spectral and timing parameters of these sources and its
interpretation in the framework of two-phase model of the accretion flow near
the compact objects; development of the quantitative model for the evolution of
GRS 1915+105 during flaring state providing direct estimate of the disk
accretion rate in the system; restrictions on the parameters of the spatial
distribution and luminosity function of the Galactic hard X-ray transient
sources; application of the the bulk motion comptonization model to the
analytic approximation of the broad--band energy spectra of Galactic black hole
candidates in the high/very high state obtained with RXTE.

</DOC>
<DOC>
<DOCNO> 100368 </DOCNO>
Amenability and exactness for dynamical systems and their C*-algebras


  In this survey, we study the relations between amenability (resp. amenability
at infinity) of C*-dynamical systems and equality or nuclearity (resp.
exactness) of the corresponding crossed products.

</DOC>
<DOC>
<DOCNO> 70488 </DOCNO>
Gribov's Confinement Scenario


  I give a brief account of Gribov's scenario of supercritical charges in QCD.
Gribov's equation for the Green function of light quarks and its derivation
from the corresponding Dyson-Schwinger equation are described. The resulting
Green function is shown to exhibit chiral symmetry breaking.

</DOC>
<DOC>
<DOCNO> 170082 </DOCNO>
Proposal for the Measurement of Bell-like Correlations from Continuous


  We show theoretically that Bell-type correlations can be observed between
continuous variable measurements performed on a parametric source. An auxiliary
measurement, performed on the detection environment, negates the possibility of
constructing a local realistic description of these correlations.

</DOC>
<DOC>
<DOCNO> 169990 </DOCNO>
Position eigenstates, symmetries, and the redundant hermiticity of


  The quantum state of a particle can be completely specified by a position at
one instant of time. This implies a lack of information, hence a symmetry, as
to where the particle will move. We here study the consequences for free
particles of spin 0 and spin 1/2. On a cubic spatial lattice a hopping equation
is derived, and the continuum limit taken. Spin 0 leads to the Schroedinger
equation, and spin 1/2 to the Weyl equation. Both Hamiltonians are hermitian
automatically, if time-reversal symmetry is assumed. Hopping amplitudes with a
"slight" inhomogeneity lead to the Weyl equation in a metric-affine space-time.

</DOC>
<DOC>
<DOCNO> 121124 </DOCNO>
Modelling 20 years of synchrotron flaring in the jet of 3C 273


  We present a phenomenological jet model which is able to reproduce well the
observed variations of the submillimetre-to-radio emission of the bright quasar
3C 273 during the last 20 years. It is a generalization of the original shock
model of Marscher & Gear (1985), which is now able to describe an accelerating
or decelerating shock wave, in a curved, non-conical and non-adiabatic jet. The
model defines the properties of a synchrotron outburst which is expected to be
emitted by the jet material in a small region just behind the shock front. By a
proper parameterization of the average outburst's evolution and of the
peculiarities of individual outbursts, we are able to decompose simultaneously
thirteen long-term light-curves of 3C 273 in a series of seventeen distinct
outbursts. It is the first time that a model is so closely confronted to the
long-term multi-wavelength variability properties of a quasar. The ability of
the model to reproduce the very different shapes of the submillimetre-to-radio
light curves of 3C 273 gives strong support to the shock model of Marscher &
Gear (1985). Indirectly, it also reinforces the idea that the outbursts seen in
the light-curves are physically linked to the distinct features observed to
move along the jet with apparently superluminal velocities.

</DOC>
<DOC>
<DOCNO> 68366 </DOCNO>
Radiative corrections of $O(\a)$ for pion beta decay in the light-front


  If the CKM matrix element $V_{ud}$, that can be derived from superallowed
nuclear decays, neutron decay and pion beta decay, is used for a precision test
of the unitarity of the CKM matrix, the combination of the present world data
seems to indicate a small violation of the unitarity condition for the first
row. While an accurate calculation of the radiative corrections of $O(\a)$ (RC)
is crucial in order to determine the value of $V_{ud}$ as precisely as
possible, the theoretical analysis has been limited in the past by the rather
crude estimate of the effect of the hadronic structure. Only the contribution
due to the axial current depends on the hadronic environment. We develop a
strategy to deal with the influence of the hadronic structure on the decay
properties of the simplest hadron, the pion, and calculate the contribution of
the axial vector current to the RC, using a light-front model for the pion. Its
$q\bar{q}$ bound state structure is well described by two parameters,
constituent quark mass and confinement scale, that have been fixed by a
comparison with the data. We take into consideration three different groups of
two-loop diagrams, and derive their light-front representations. We discuss the
associated zero-mode problem and show that the respective light-front
amplitudes are free of spurious contributions. There is only a small model
dependent uncertainty of the final result for the RC for pion beta decay.

</DOC>
<DOC>
<DOCNO> 71171 </DOCNO>
Neutrino Interactions In Color-Flavor-Locked Dense Matter


  At high density, diquarks could condense in the vacuum with the QCD color
spontaneously broken. Based on the observation that the symmetry breaking
pattern involved in this phenomenon is essentially the same as that of the
Pati-Salam model with broken electroweak--color SU(3) group, we determine the
relevant electroweak interactions in the color-flavor locked (CFL) phase in
high density QCD. We briefly comment on the possible implications on the
cooling of neutron stars.

</DOC>
<DOC>
<DOCNO> 11754 </DOCNO>
Shubnikov-de Haas effect and Yamaji oscillations in the


  Shubnikov-De Haas effect (SdH) effect and angular dependent magnetoresistance
oscillations (AMRO) were observed in the organic superconductor:
$\kappa$-(BETS)$_2$FeBr$_4$. In contrast to its isostructural compound
$\kappa-(BETS)$_2$FeCl$_4$, SdH oscillations, for fields perpendicular to the
conducting planes, reveal three Fermi Surface (FS) closed orbits $\alpha$,
$\beta$, and $\gamma$ whose cross sectional areas are 19.8 %, 99.9 %, and 2.4 %
of the first Brillouin zone, respectively. The conduction electron effective
masses were found to be: $\mu_{\alpha} = (4.7 \pm 0.2)$ m$_e$, $\mu_{\beta} =
(8.0 \pm 1.0)$ m$_e$, and $\mu_{\gamma} = (2.0 \pm 0.2)$ m$_e$. The observation
of a $\gamma$ orbit is not expected from band structure calculations,
$\mu_{\beta}$ is among the heaviest masses ever reported for an organic
conductor. The observed Yamaji-like AMRO indicates a 2-D closed FS, warped
along the $k_z$ direction.

</DOC>
<DOC>
<DOCNO> 99914 </DOCNO>
Explicit regulator maps on polylogarithmic motivic complexes


  We define a regulator map from the weight n polylogarithmic motivic complex
to the weight n Deligne complex of an algebraic variety X. The regulator map is
constructed explicitly via the classical polylogarithms with some funny
combinations of Bernoulli numbers as coefficients. This leads to conjectures on
special values of L-functions at s=n which reduce to Zagier's conjecture when X
is of dimension zero over Q.
  The cone of this map, shifted by one, should be called the Arakelov motivic
complex of X. Its last cohomology group is identified with a group of
codimension n Arakelov cycles on X.

</DOC>
<DOC>
<DOCNO> 80883 </DOCNO>
B^0-\bar{B}^0 mixing with quenched lattice NRQCD


  We present our recent results for the B-parameters, which parameterize the
\Delta B=2 transition amplitudes. Calculations are made in quenched QCD at
\beta=5.7, 5.9, and 6.1, using NRQCD for heavy quark and the $O(a)$-improved
action for light quark. The operators are perturbatively renormalized including
corrections of O(\alpha_s/am_Q). We examine scaling behavior of the
B-parameters in detail, and discuss the systematic uncertainties using scatter
of results with different analysis procedures adopted. As a result, we find
B_{B_d}(m_b)=0.84(2)(8), B_{B_s}/B_{B_d}=1.017(10)(^{+4}_{-0}) and
B_{S_s}(m_b)=0.87(1)(9)(^{+1}_{-0}) in the quenched approximation.

</DOC>
<DOC>
<DOCNO> 13274 </DOCNO>
Magnetic Fingerprints in Superconducting Au$_{0.7}$In$_{0.3}$ Cylinders


  Reproducible, sample-specific magnetoresistance fluctuations (magnetic
fingerprints) were observed in the low-temperature part of the superconducting
transition regime of hollow Au$_{0.7}$In$_{0.3}$ cylinders of submicron
diameter. The amplitude of the fluctuations was found to exceed that of the
universal conductance fluctuation in normal metals by several orders of
magnitude. The physical origin of these observations is related to mesoscopic
fluctuations of the superconducting order parameter.

</DOC>
<DOC>
<DOCNO> 10619 </DOCNO>
Note on the Chandrasekhar Model of the Optical Activity of Crystals


  In this paper we discuss more wide applicability of the Chandrasekhar model
of coupled oscillators in the optical rotatory dispersion of the crystals. We
solve the problem using the Chandrasekhar model of two coupled oscillators in
the case when we include all couplings between adjacent oscillators on the
helix that is given by the crystal structure. Further we discuss the results of
coupled oscillators models in the case of the including of the couplings
between even and odd oscillators on the helix. The optical rotatory dispersion
results obtained after the approximations of the oscillator strengths verify
that these couplings have the important influence on the crystal optical
rotatory dispersion.

</DOC>
<DOC>
<DOCNO> 9859 </DOCNO>
Sonic black holes in dilute Bose-Einstein condensates


  The sonic analog of a gravitational black hole in dilute-gas Bose-Einstein
condensates is investigated. It is shown that there exist both dynamically
stable and unstable configurations which, in the hydrodynamic limit, exhibit a
behavior completely analogous to that of gravitational black holes. The
dynamical instabilities involve creation of quasiparticle pairs in positive and
negative energy states. We illustrate these features in two qualitatively
different one-dimensional models, namely, a long, thin condensate with an
outcoupler laser beam providing an ``atom sink,'' and a tight ring-shaped
condensate. We have also simulated the creation of a stable sonic black hole by
solving the Gross-Pitaevskii equation numerically for a condensate subject to a
trapping potential which is adiabatically deformed. A sonic black hole could in
this way be created experimentally with state-of-the-art or planned technology.

</DOC>
<DOC>
<DOCNO> 68147 </DOCNO>
A New Mechanism for J/psi Suppression in Nuclear Collisions


  We present new results based on an improved version of the Glauber model,
used to describe the nuclear absorption of J/psi in reactions between nuclei at
high energy. The excitation of the colour degrees of freedom of nucleons, due
to collisions mediated by one-gluon exchange, is taken into account. It is
found that the proposed mechanism leads to larger nuclear absorption of J/psi
than previously considered.

</DOC>
<DOC>
<DOCNO> 118955 </DOCNO>
X-rays from Radio-Galaxies: BeppoSAX Observations


  We briefly review BeppoSAX observations of X-ray bright radio-galaxies. Their
X-ray spectra are quite varied, and perhaps surprisingly, any similarity
between radio-loud AGN and Seyfert galaxies is the exception rather than the
rule. When detected, reprocessing features (iron line and reflection) are
generally weak, suggesting two possible scenarios: either: (1) non-thermal
(jet?) radiation dilutes the X-ray emission from the disk in radio-loud
objects, or (2) the solid angle subtended by the X-ray reprocessing material is
smaller in radio-loud than in radio-quiet AGN due to different characteristics
of the accretion disk itself.

</DOC>
<DOC>
<DOCNO> 119532 </DOCNO>
The response of the X-ray luminosity to the interaction strength in


  We have correlated a sample of 99 Seyfert 1 and 98 Seyfert 2 (Rafanelli et
al., 1995) interacting galaxies with the survey and pointed ROSAT data and have
detected 91 Seyferts 1 and 47 Seyfert 2s in the X-ray band. We have performed
spectral and timing analysis of the X-ray detected sources, and we have
examined the relation of the X-ray luminosity L_X with the interaction strength
Q.

</DOC>
<DOC>
<DOCNO> 11745 </DOCNO>
Instabilities in Josephson Ladders with Current Induced Magnetic Fields


  We report on a theoretical analysis, consisting of both numerical and
analytic work, of the stability of synchronization of a ladder array of
Josephson junctions under the influence of current induced magnetic fields.
Surprisingly, we find that as the ratio of the mutual to self inductance of the
cells of the array is increased a region of unstable behavior occurs followed
by reentrant stable synchronization. Analytic work tells us that in order to
understand fully the cause of the observed instabilities the behavior of the
vertical junctions, sometimes ignored in analytic analyses of ladder arrays,
must be taken into account.

</DOC>
<DOC>
<DOCNO> 116302 </DOCNO>
Coexistence of thermal noise and squeezing in the intensity fluctuations


  The intensity fluctuations of laser light are derived from photon number rate
equations. In the limit of short times, the photon statistics for small laser
devices such as typical semiconductor laser diodes show thermal characteristics
even above threshold. In the limit of long time averages represented by the low
frequency component of the noise, the same devices exhibit squeezing. It is
shown that squeezing and thermal noise can coexist in the multi-mode output
field of laser diodes. This result implies that the squeezed light generated by
regularly pumped semiconductor laser diodes is qualitatively different from
single mode squeezed light. In particular, no entanglement between photons can
be generated using this type of collective multi-mode squeezing.

</DOC>
<DOC>
<DOCNO> 123300 </DOCNO>
Nonlinear Stochastic Biasing of Peaks and Halos: Scale-Dependence,


  We quantify the degree of nonlinearity and stochasticity of the clustering of
biased objects, using cosmological N-body simulations. Adopting the peaks and
the halos as representative biasing models, we focus on the two-point
correlation of the biased objects, dark matter and their cross-correlation.
Especially, we take account of the effect of redshift-space distortion and
attempt to clarify the scale-dependence and the time-dependence by analyzing
the biasing factor and the cross-correlation factor. On small scales,
stochasticity and nonlinearity become appreciable and strongly
object-dependent, especially in redshift space due to the pair-wise velocity
dispersion of the biased objects. Nevertheless, an approximation of
deterministic linear biasing $\delta_{\rm obj}\simeq b_{\rm obj} \delta_{\rm
mass}$ works reasonably well even in the quasi-linear regime $r > 10 h^{-1}$
Mpc, and linear redshift-space distortion explains the clustering amplitudes in
redshift space in this regime.

</DOC>
<DOC>
<DOCNO> 100928 </DOCNO>
The Curvature of a Single Operator on a Hilbert Space


  This note studies Arveson's curvature invariant for d-contractions
specialized to the case d=1 of a single contraction operator on a Hilbert
space. It establishes a formula which gives an easy-to-understand meaning for
the curvature of a single contraction. The formula is applied to give an
example of an operator with nonintegral curvature. Under the additional
hypothesis that the contraction T be "pure", we show that its curvature K(T) is
given by K(T) = - index(T) := -(dim ker T - dim coker T).

</DOC>
<DOC>
<DOCNO> 121825 </DOCNO>
Microlensing results from APO monitoring of the double quasar


  If the halo of the lensing galaxy 0957+561 is made of massive compact objects
(MACHOs), they must affect the lightcurves of the quasar images Q0957+561 A and
B differently. We search for this microlensing effect in the double quasar by
comparing monitoring data for the two images A and B - obtained with the 3.5m
Apache Point Observatory from 1995 to 1998 - with intensive numerical
simulations. This way we test whether the halo of the lensing galaxy can be
made of MACHOs of various masses. We can exclude a halo entirely made out of
MACHOs with masses between 10e(-6) Msun and 10e(-2) Msun for quasar sizes of
less than 3*10e(14)cm (h = 0.6), hereby extending previous limits upwards by
one order of magnitude.

</DOC>
<DOC>
<DOCNO> 150403 </DOCNO>
Cancellation of linearised axion-dilaton self interaction divergence in


  The force densities exerted on a localised material system by linearised
interaction with fields of axionic and dilatonic type are shown to be
describable very generally by relatively simple expressions that are well
behaved for fields of purely external origin, but that will be subject to
ultraviolet divergences requiring regularisation for fields arising from self
interaction in submanifold supported ``brane'' type systems. In the particular
case of 2-dimensionally supported, i.e. string type, system in an ordinary
4-dimensional background it is shown how the result of this regularisation is
expressible in terms of the worldsheet curvature vector $K^\mu$, and more
particularly that (contrary to what was suggested by early work on this
subject) for a string of Nambu Goto type the divergent contribution from the
dilatonic self action will always be directed oppositely to its axionic
counterpart. This makes it possible for the dilatonic and axionic divergences
to entirely cancel each other out (so that there is no need of a
renormalisation to get rid of ``infinities'') when the relevant coupling
coefficents are related by the appropriate proportionality condition provided
by the low energy limit of superstring theory.

</DOC>
<DOC>
<DOCNO> 9713 </DOCNO>
Collective Spin Fluctuation Mode and Raman Scattering in Superconducting


  Although the low frequency electronic Raman response in the superconducting
state of the cuprates can be largely understood in terms of a d-wave energy
gap, a long standing problem has been an explanation for the spectra observed
in the $A_{1g}$ polarization orientations. We present calculations which
suggest that the peak position of the observed $A_{1g}$ spectra is due to a
collective spin fluctuation mode.

</DOC>
<DOC>
<DOCNO> 11704 </DOCNO>
Relaxation schemes for normal modes of magnetic vortices: Application to


  Relaxation schemes for finding normal modes of nonlinear excitations are
described, and applied to the vortex-spinwave scattering problem in classical
two-dimensional easy-plane Heisenberg models. The schemes employ the square of
an effective Hamiltonian to ensure positive eigenvalues, together with an
evolution in time or a self-consistent Gauss-Seidel iteration producing
diffusive relaxation. We find some of the lowest frequency spinwave modes in a
circular system with a single vortex present. The method is used to describe
the vortex-spinwave scattering (S-matrix and phase shifts) and other dynamical
properties of vortices in ferromagnets and antiferromagnets, for systems larger
than that solvable by diagonalization methods. The lowest frequency modes
associated with translation of the vortex center are used to estimate the
vortex mass.

</DOC>
<DOC>
<DOCNO> 71741 </DOCNO>
Extended quintessence and the primordial helium abundance


  In extended quintessence models, a scalar field which couples to the
curvature scalar R provides most of the energy density of the universe. We
point out that such models can also lead naturally to a decrease in the
primordial abundance of helium-4, relieving the tension which currently exists
between the primordial helium-4 abundance inferred from observations and the
amount predicted by Standard Big Bang Nucleosynthesis (SBBN) corresponding to
the observed deuterium abundance. Using negative power-law potentials for the
quintessence field, we determine the range of model parameters which can lead
to an interesting reduction in the helium-4 abundance, and we show that it
overlaps with the region allowed by other constraints on extended quintessence
models.

</DOC>
<DOC>
<DOCNO> 71241 </DOCNO>
Stars and black holes in varying speed of light theories


  We investigate spherically symmetric solutions to a recently proposed
covariant and locally Lorentz-invariant varying speed of light theory. We find
the metrics and variations in $c$ associated with the counterpart of black
holes, the outside of a star, and stellar collapse. The remarkable novelty is
that $c$ goes to zero or infinity (depending on parameter signs) at the
horizon. We show how this implies that, with appropriate parameters, observers
are prevented from entering the horizon. Concomitantly stellar collapse must
end in a ``Schwarzchild radius'' remnant. We then find formulae for
gravitational light deflection, gravitational redshift, radar echo delay, and
the precession of the perihelion of Mercury, highlighting how these may differ
distinctly from their Einstein counterparts but still evade experimental
constraints. The main tell-tale signature of this theory is the prediction of
the observation of a different value for the fine structure constant, $\alpha$,
in spectral lines formed in the surface of stars. We close by mentioning a
variety of new classical and quantum effects near stars, such as aging
gradients and particle production.

</DOC>
<DOC>
<DOCNO> 100987 </DOCNO>
Relation between the dimensions of the ring generated by a vector bundle


  M. Nori proved that on a projective smooth variety, a bundle is finite, (that
is the ring it generates has dimension 0), if and only if it trivializes on a
finite cover. In this note, we consider bundles of degree 0 on an elliptic
curve. We prove that the dimension of the ring generated by such a bundle is
the same as the dimension of a torsor trivializing the bundle (and is 1).

</DOC>
<DOC>
<DOCNO> 11073 </DOCNO>
Conductivity of Doped Two-Leg Ladders


  Recently, conductivity measurements were performed on the hole-doped two-leg
ladder material Sr_{14-x}Ca_xCu_{24}O_{41}. In this work, we calculate the
conductivity for doped two-leg ladders using a model of hole-pairs forming a
strongly correlated liquid - a single component Luttinger liquid - in the
presence of disorder. Quantum interference effects are handled using
renormalization group methods. We find that our model can account for the low
energy features of the experimental results. However, at higher energies the
experiments show deviations from the predictions of this model. Using the
results of our calculations as well as results on the ground state of doped
two-leg ladders, we suggest a scenario to account for the higher energy
features of the experimental results.

</DOC>
<DOC>
<DOCNO> 102266 </DOCNO>
Compatible sequences and a slow Winkler percolation


  Two infinite 0-1 sequences are called compatible when it is possible to cast
out 0's from both in such a way that they become complementary to each other.
Answering a question of Peter Winkler, we show that if the two 0-1-sequences
are random i.i.d. and independent from each other, with probability p of 1's,
then if p is sufficiently small they are compatible with positive probability.
The question is equivalent to a certain dependent percolation with a power-law
behavior: the probability that the origin is blocked at distance n but not
closer decreases only polynomially fast and not, as usual, exponentially.

</DOC>
<DOC>
<DOCNO> 117328 </DOCNO>
Linear Exp-6 Isotherm for Compressed Molten Cesium over the Whole Liquid


  The Linear exp-6 isotherm is presented as an approach to the thermodynamic
properties of liquid alkali metals over the whole liquid range including
metal-nonmetal transition. The exp-6 pair interaction potential is applied to
approach the underlying interplay between the characteristics soft repulsive
interaction in dense, large attractive interaction in expanded liquid alkali
metal and the observed thermodynamic properties. PVT of a dense liquid alkali
metals obey the linear exp-6 isotherm(Z-1)V2=A+Br-7/3exp{a(1-Cr-1/3/rm)} over
the whole range of liquid densities, where Z is the compression factor,r=1/V is
the density, rm is the position of potential minimum and a is a parameter and C
is a constant. The intercept A and the slope B significantly are related to

</DOC>
<DOC>
<DOCNO> 119764 </DOCNO>
The Evolution of Magnetic Field and Spin Period of Accreting Neutron


  Based on the accretion induced magnetic a field decay model, in which a
frozen field and an incompressible fluid are assumed, we obtain the following
results. (1) An analytic relation between the magnetic field and spin period,
if the fastness parameter of the accretion disk is neglected.
  The evolutionary tracks of accreting neutron stars in the P-B diagram in our
model are different from the equilibrium period lines when the influence of the
fastness parameter is taken into account. (2) The theoretical minimum spin
period of an accreting neutron star is $\max (1.1{\rm ms}(\frac{\Delta
M}{M_{\odot}})^{-1} R^{-5/14}_6 I_{45}(\frac{M}{M_{\odot}})^{-1/2}, 1.1{\rm ms}
(\frac{M}{M_{\odot}})^{-1/2} R^{17/14}_6)$, independent of the accretion rate
(X-ray luminosity) but dependent on the total accretion mass $\Delta M$.
However, the minimum magnetic field depends on the accretion rate. (3) The
magnetic field strength decreases faster with time than the period.

</DOC>
<DOC>
<DOCNO> 13598 </DOCNO>
Fermi surface, pseudogaps and dynamical stripes in La2-xSrxCuO4


  Doping dependence of the electronic structure of La$_{2-x}$Sr$_x$CuO$_4$
(LSCO) has been systematically studied in a series of photoemission
measurements. The unusual spectral features in the underdoped regime are
attributed to the formation of dynamical stripes and the opening of large and
small pseudogaps.

</DOC>
<DOC>
<DOCNO> 151347 </DOCNO>
Nonabelian topological mass mechanism for a three-dimensional 2-form


  Starting from a recently proposed abelian topological model in (2+1)
dimensions, we use the method of the consistent deformations to prove that a
topologically massive model involving the Kalb-Ramond two form field does not
admit a nonabelian generalization. The introduction of a connection-type one
form field keeps the previous result. However we show that the goal is achieved
if we introduce a vectorial auxiliary field, exhibiting a nonabelian
topological mass generation mechanism in D=3, that provides mass for the
Kalb-Ramond field. Further, we find the complete set of BRST and anti-BRST
equations using the horizontality condition, suggesting a connection between
this formalism and the method of the consistent deformations.

</DOC>
<DOC>
<DOCNO> 13650 </DOCNO>
The Saffman-Taylor problem on a sphere


  The Saffman-Taylor problem addresses the morphological instability of an
interface separating two immiscible, viscous fluids when they move in a narrow
gap between two flat parallel plates (Hele-Shaw cell). In this work, we extend
the classic Saffman-Taylor situation, by considering the flow between two
curved, closely spaced, concentric spheres (spherical Hele-Shaw cell). We
derive the mode-coupling differential equation for the interface perturbation
amplitudes and study both linear and nonlinear flow regimes. The effect of the
spherical cell (positive) spatial curvature on the shape of the interfacial
patterns is investigated. We show that stability properties of the fluid-fluid
interface are sensitive to the curvature of the surface. In particular, it is
found that positive spatial curvature inhibits finger tip-splitting. Hele-Shaw
flow on weakly negative, curved surfaces is briefly discussed.

</DOC>
<DOC>
<DOCNO> 99546 </DOCNO>
Wave Invariants for Non-degenerate Closed Geodesics


  This paper generalizes the methods and results of our article xxx.lanl.gov
math.SP/0002036 from elliptic to general non-degenerate closed geodesics. The
main purpose is to introduce a quantum Birkhoff normal form of the Laplacian at
a general non-degenerate closed geodesic in the sense of V.Guillemin. Guillemin
proved that the coefficients of the normal form at an elliptic closed geodesic
could be determined from the wave invariants of this geodesic. We give a new
proof, and extend its range to any non-degenerate closed geodesic.

</DOC>
<DOC>
<DOCNO> 84446 </DOCNO>
Existence, uniqueness and other properties of the BCT (minimal strain


  Brady, Creighton and Thorne have proposed a choice of the lapse and shift for
numerical evolutions in general relativity that extremizes a measure of the
rate of change of the three-metric (BCT gauge). We investigate existence and
uniqueness of this gauge, and comment on its use in numerical time evolutions.

</DOC>
<DOC>
<DOCNO> 8051 </DOCNO>
Statistical mechanics of money


  In a closed economic system, money is conserved. Thus, by analogy with
energy, the equilibrium probability distribution of money must follow the
exponential Gibbs law characterized by an effective temperature equal to the
average amount of money per economic agent. We demonstrate how the Gibbs
distribution emerges in computer simulations of economic models. Then we
consider a thermal machine, in which the difference of temperatures allows one
to extract a monetary profit. We also discuss the role of debt, and models with
broken time-reversal symmetry for which the Gibbs law does not hold.

</DOC>
<DOC>
<DOCNO> 69689 </DOCNO>
Asymmetric Quarks in the Proton


  Asymmetries in the quark momentum distributions in the proton reveal
fundamental aspects of strong interaction physics. Differences between u-bar
and d-bar quarks in the proton sea provide insight into the dynamics of the
pion cloud around the nucleon and the nature of chiral symmetry breaking.
Polarized flavor asymmetries allow the effects of pion clouds to be
disentangled from those of antisymmetrization. Asymmetries between s and s-bar
quark distributions in the nucleon are also predicted from the chiral
properties of QCD.

</DOC>
<DOC>
<DOCNO> 12695 </DOCNO>
Dark solitons in a two-component Bose-Einstein condensate


  The creation and interaction of dark solitons in a two-component
Bose-Einstein condensate is investigated. For a miscible case, the interaction
of dark solitons in different components is studied. Various possible scenarios
are presented, including the formation of a soliton-soliton bound pair. We also
analyze the soliton propagation in the presence of domains, and show that a
dark soliton can be transferred from one component to the other at the domain
wall when it exceeds a critical velocity. For lower velocities multiple
reflections within the domain are observed, where the soliton is evaporated and
accelerated after each reflection until it finally escapes from the domain.

</DOC>
<DOC>
<DOCNO> 170346 </DOCNO>
Quantum Measurement and Shannon Information, A Reply to M. J. W. Hall


  Motivated by Hall's recent comment in quant-ph/0007116 we point out in some
detail the essence of our reasoning why we believe that Shannon's information
is not an adequate choice when defining the information gain in quantum
measurements as opposed to classical observations.

</DOC>
<DOC>
<DOCNO> 102649 </DOCNO>
On a generic inverse differential Galois problem for GL_n


  \newcommand{\GLn}{\operatorname{GL}_n} \newcommand{\GL}{\GLn(C)}
  Let $F$ be a differential field with algebraically closed field of constants
$C$. We prove that $F< Y_{ij}>(X_{ij})\supset F< Y_{ij}>$ is a generic
Picard-Vessiot extension of $F$ for $\GL$. If $E\supset F$ is any
Picard-Vessiot extension with differential Galois group $\GL$ then $E\cong
F(X_{ij})$ as $F$- and $\GL$-modules and there are $f_{ij}\in F$ such that $F<
Y_{ij}>(X_{ij})\supset F< Y_{ij}>$ specializes to $E\supset F$ via $
Y_{ij}\mapsto f_{ij}$. The $[f_{ij}]\in M_n(F)$ for which the image of the map
$ Y_{ij}\mapsto f_{ij}$ is a Picard-Vessiot extension of $F$ with group $\GL$
can be characterized as those $[f_{ij}]\in M_n(F)$ for which the wronskians of
the monomials in $F< Y_{ij}>(X_{ij})$ of degree less than or equal to $k$ all
map to non-zero elements under $ Y_{ij}\mapstof_{ij}$.

</DOC>
<DOC>
<DOCNO> 116485 </DOCNO>
Second-harmonic interferometric spectroscopy of the buried


  The second-harmonic interferometric spectroscopy (SHIS) which combines both
amplitude (intensity) and phase spectra of the second-harmonic (SH) radiation
is proposed as a new spectroscopic technique being sensitive to the type of
critical points (CP's) of combined density of states at semiconductor surfaces.
The increased sensitivity of SHIS technique is demonstrated for the buried
Si(111)-SiO$_2$ interface for SH photon energies from 3.6 eV to 5 eV and allows
to separate the resonant contributions from $E^\prime_0/E_1$, $E_2$ and
$E^\prime_1$ CP's of silicon.

</DOC>
<DOC>
<DOCNO> 118429 </DOCNO>
Interaction in Abell 2256: the BeppoSAX view


  We present results from a spatially resolved spectral analysis of the merging
cluster Abell 2256. The long integration time (135 ks) and the good spatial
resolution of the MECS onboard BeppoSAX allow us to derive a new and
substantially improved measurement of the temperature structure. We find that,
within a central region of the cluster, where the effects of the merger are
visible in the ROSAT surface brightness image, the azimuthally averaged
projected temperature is remarkably flat; outside this region the projected
temperature rapidly declines. The BeppoSAX data also shows clear evidence of an
azimuthal temperature gradient in the 4'-8' (0.4-0.8 Mpc) radial bin, oriented
in the same direction as the merger itself. Our metal abundance profile shows,
for the first time, firm evidence of an abundance gradient in a rich merging
cluster. Intriguingly the abundance map shows, in the SE sector, i.e. the one
furthest away from the merger, a sharp factor of two drop in abundance at a
radius comparable to the core radius of the cluster. A possible interpretation
is that, prior to the merger event, a cooling flow had already developed in the
core of the infalling subgroup, as suggested by Fabian and Daines (1991). The
interaction between the substructures would have disrupted the cooling flow
thereby re-heating and re-mixing the gas. As the merger in A2256 is still in a
relatively early stage, the gas located on the side opposite to the merger
event would still retain the low abundances associated with the intra-cluster
medium (ICM) prior to the cooling flow disruption.

</DOC>
<DOC>
<DOCNO> 84846 </DOCNO>
Non Parallels Electric and Magnetic Fields in a F.R.W. Cosmology.


  At first, we discuss parallels electric and magnetic fields solutions in a
gravitational background. Then, considering eletromagnetic and gravitational
waves symmetries we show a particular solution for stationary gravitational
waves. Finally we consider gravitation as a gauge theory (effective
gravitational theory), evaluate the propagators of the model, analyze the
corresponding quantum excitations and verify (confirm) the tree-level unitarity
at many places of the model.

</DOC>
<DOC>
<DOCNO> 83270 </DOCNO>
The X-Files: Investigating Alien Performance in a Thin-client World


  Many scientific applications use the X11 window environment; an open source
windows GUI standard employing a client/server architecture. X11 promotes:
distributed computing, thin-client functionality, cheap desktop displays,
compatibility with heterogeneous servers, remote services and administration,
and greater maturity than newer web technologies. This paper details the
author's investigations into close encounters with alien performance in
X11-based seismic applications running on a 200-node cluster, backed by 2 TB of
mass storage. End-users cited two significant UFOs (Unidentified Faulty
Operations) i) long application launch times and ii) poor interactive response
times. The paper is divided into three major sections describing Close
Encounters of the 1st Kind: citings of UFO experiences, the 2nd Kind: recording
evidence of a UFO, and the 3rd Kind: contact and analysis. UFOs do exist and
this investigation presents a real case study for evaluating workload analysis
and other diagnostic tools.

</DOC>
<DOC>
<DOCNO> 116572 </DOCNO>
Optimal Mutation Rates on Static Fitness Landscpes


  We study the evolution of mutation rates for an asexual population living on
a static fitness landscape, consisting of multiple peaks forming an
evolutionary staircase. The optimal mutation rate is found by maximizing the
diffusion towards higher fitness. Surprisingly the optimal genomic copying
fidelity is given by Q = e^(-1/ln(n)) (where n is the genome length),
independent of all other parameters in the model. Simulations confirm this
theoretical result. We also discuss the relation between the optimal mutation
rate on static and dynamic fitness landscapes.

</DOC>
<DOC>
<DOCNO> 72012 </DOCNO>
Effects from the charm scale in K+ -> pi+ nu nubar


  We consider contributions to the rare decay K+ -> pi+ nu nubar which become
nonlocal at the charm scale. Compared to the leading term, such amplitudes are
suppressed by two powers of mK/mc and could potentially give corrections at the
level of 15%. We compute the leading coefficients of the subleading dimension
eight operators in the effective theory below the charm mass. The matrix
elements of these operators cannot all be calculated from first principles and
some must be modeled. We find that these contributions are likely to be small,
but the estimate is sufficiently uncertain that the result may be as large as
the existing theoretical uncertainty from other sources.

</DOC>
<DOC>
<DOCNO> 99903 </DOCNO>
Poles and zeros of the scattering matrix associated to defect modes


  We analyze electromagnetic waves propagation in one-dimensional periodic
media with single or periodic defects. The study is made both from the point of
view of the modes and of the diffraction problem. We provide an explicit
dispersion equation for the numerical calculation of the modes, and we
establish a connection between modes and poles and zeros of the scattering
matrix.

</DOC>
<DOC>
<DOCNO> 99441 </DOCNO>
Cohomology on Toric Varieties and Local Cohomology with Monomial


  We study the local cohomology modules H^i_B(R) for a reduced monomial ideal B
in a polynomial ring R=k[X_1,...,X_n]. We consider a grading on R which is
coarser than the Z^n-grading such that each component of H^i_B(R) is finite
dimensional and we give an effective way to compute these components. Using
Cox's description for sheaves on toric varieties, we apply these results to
compute the cohomology of coherent sheaves on toric varieties. We give
algorithms for this computation which have been implemented in the Macaulay 2
system. We obtain also a topological description for the cohomology of rank one
torsionfree sheaves on toric varieties.

</DOC>
<DOC>
<DOCNO> 121176 </DOCNO>
Galaxies at High Redshift


  Within just the last few years, we have advanced from knowing only a few
galaxies at z>2 to having redshifts for nearly 1000 z~2-5 objects. The majority
of this sample has been detected through the photometric ``drop-out'' technique
used so successfully by Steidel and his collaborators. In addition, a handful
of objects have already been detected at z>5, and we may already have a few
objects at z>6! These data, plus that at z<2 have resulted in a
characterization of the star formation history of the universe, commonly known
as the ``Madau plot'', which gives SFR per comoving volume vs redshift from the
present day at z=0 to z~5. Recently, we have realized that dust has
significantly affected our SFR estimates for the objects that have been
detected in the optical, and have developed approaches to correct for that
extinction. We now also have increasingly good evidence that a substantial
fraction (>50%?) of the high redshift star formation occurs in dust-enshrouded
starbursts that were detected at 850 micron with a submm bolometer SCUBA on the
JCMT telescope. These objects will typically be too faint to detect and measure
redshifts in the optical, though those that can have already provided valuable
constraints. The highest redshift objects at z~5 and beyond are intriguing
sources, but test even the limits of Keck and of HST. The detailed study of
such sources may well only be practical for gravitationally-lensed objects,
where the high magnification allows for a much more detailed study of the
proto-galaxy's structure, until even larger space-based (NGST) and ground-based
(30-m plus) telescopes are developed.

</DOC>
<DOC>
<DOCNO> 10816 </DOCNO>
Evidence for the immobile bipolaron formation in the paramagnetic state


  Recent research suggests that the charge carriers in the paramagnetic state
of the magnetoresistive manganites are small polarons. Here we report studies
of the oxygen-isotope effects on the intrinsic resistivity and thermoelectric
power in several ferromagnetic manganites. The precise measurements of these
isotope effects allow us to make a quantitative data analysis. Our results do
not support a simple small-polaron model, but rather provide compelling
evidence for the presence of small immobile bipolarons, i.e., pairs of small
polarons. Since the bipolarons in the manganites are immobile, the present
result alone appears not to give a positive support to the bipolaronic
superconductivity theory for the copper-based perovskites.

</DOC>
<DOC>
<DOCNO> 12618 </DOCNO>
Oscillatory Driving of Crystal surfaces: a Route to Controlled Pattern


  We show that the oscillatory driving of crystal surfaces can induce pattern
formation or smoothening. The driving force can be of quite different origin
such as a pulsed laser beam, an electric field, or elasticity. Depending on
driving conditions, step bunching and meandering, mound formation, or surface
smoothening may be seen in presence of a kinetic asymmetry at the steps or
kinks (the Ehrlich-Schwoebel effect). We employ a step model to calculate the
induced mass flux along misoriented surfaces, which accounts for surface
dynamics and stability. Flux inversion is found when varying the driving
frequency. Slope selection and metastability result from the cancellation of
the mass flux along special orientations. Kinetic Monte Carlo simulations
illustrate these points.

</DOC>
<DOC>
<DOCNO> 13307 </DOCNO>
Spin effects in the magneto-drag between double quantum wells


  We report on the selectivity to spin in a drag measurement. This selectivity
to spin causes deep minima in the magneto-drag at odd fillingfactors for
matched electron densities at magnetic fields and temperatures at which the
bare spin energy is only one tenth of the temperature. For mismatched densities
the selectivity causes a novel 1/B-periodic oscillation, such that negative
minima in the drag are observed whenever the majority spins at the Fermi
energies of the two-dimensional electron gasses (2DEGs) are anti-parallel, and
positive maxima whenever the majority spins at the Fermi energies are parallel.

</DOC>
<DOC>
<DOCNO> 70115 </DOCNO>
Further studies on relic neutrino asymmetry generation II: a rigorous


  We derive an approximate relic neutrino asymmetry evolution equation that
systematically incorporates repopulation processes from the full quantum
kinetic equations (QKEs). It is shown that in the collision dominant epoch, the
said equation reduces precisely to the expression obtained previously from the
static/adiabatic approximation. The present treatment thus provides a rigorous
justification for the seemingly incongruous assumptions of a negligible
repopulation function and instantaneous repopulation sometimes employed in
earlier works.

</DOC>
<DOC>
<DOCNO> 116746 </DOCNO>
Temperature of the SN1987A supernova provides an estimate of the


  Numerous estimates of upper bounds on the (anti)neutrino rest mass have been
published based on the SN1987A observations.
  Here, we use a nonkinematic (thermal) time extent to provide a rest mass
estimate of a few eV (as mc^2 mass), if not zero. In the solution, we find that
a typical upper bound formula for the mass implies that this thermal extent was
attributable to about 10% of the particle energy measured on Earth. The present
approach yields an expected value for the mass, given any theoretical or model
dependent estimate of the fraction of the detected neutrino energy attributable
to the supernova temperature.

</DOC>
<DOC>
<DOCNO> 120403 </DOCNO>
The frequency of nuclear star-formation in Seyfert 2 galaxies


  We investigate the detectability of starburst signatures in the nuclear
spectrum of Seyfert 2 galaxies by constructing spectral models in the
wavelength range 3500-4100A, combining the spectrum of a bulge population (of
age ~10Gyr) with that of younger stellar populations, spanning ages from ~3 Myr
to 1 Gyr. We also construct models combining the bulge template with a
power-law (PL) continuum, which is observed in some Seyfert 2's in polarized
light, contributing with typically 10-40% of the flux at 4020A. We conclude
that such continuum cannot be distinguished from that of a very young stellar
population (age < 10 Myr), contributing with less than ~0.02% of the mass of
the bulge. The models are compared with nuclear spectra - corresponding to a
radius of 200-300 pc at the galaxy - of 20 Seyfert 2 galaxies, in which we
specifically look for the signatures above of young to intermediate age stellar
populations. We find them in ten galaxies, thus 50% of the sample. But only in
six cases (30% of the sample) they can be attributed to young stars (age < 500
Myr): Mrk 1210, ESO 362-G8, NGC 5135, NGC 5643, NGC 7130 and NGC 7582. In the
remaining four cases, the signatures are due to intermediate age stars (~1
Gyr). We find a tendency for the young stars to be found more frequently among
the late type Seyfert's. This tendency is supported by a comparison between the
equivalent widths (W) of absorption lines of the nuclear spectra of the Seyfert
2's with those of normal galaxies of the same Hubble type.

</DOC>
<DOC>
<DOCNO> 102591 </DOCNO>
On asymptotic dimension of groups


  We prove a version of the countable union theorem for asymptotic dimension
and we apply it to groups acting on asymptotically finite dimensional metric
spaces. As a consequence we obtain the following finite dimensionality
theorems. A) An amalgamated product of asymptotically finite dimensional groups
has finite asymptotic dimension: asdim A *_C B < infinity. B) Suppose that G'
is an HNN extension of a group G with asdim G < infinity. Then asdim G'<
infinity. C) Suppose that \Gamma is Davis' group constructed from a group \pi
with asdim\pi < infinity. Then asdim\Gamma < infinity.

</DOC>
<DOC>
<DOCNO> 69910 </DOCNO>
Primordial Spectrum of Gauge Fields from Inflation


  We show that conformal invariance of gauge fields is naturally broken in
inflation, having as a consequence amplification of gauge fields. The resulting
spectrum of the field strength is approximately B_L ~ L^(-1), where L is the
relevant coherence scale. One realisation of our scenario is scalar
electrodynamics with a scalar whose mass is large enough to evade observational
constraints - the obvious candidates being supersymmetric partners of the
standard-model fermions. Our mechanism also leads naturally to amplification of
the standard-model Z-boson field due to its coupling to the electroweak Higgs
field. At preheating, the spectrum of the Z field is transferred to the
hypercharge field, which remains frozen in the plasma and is converted into a
magnetic field at the electroweak phase transition. With a reasonable model of
field evolution one obtains a magnetic field strength of the order of
$10^{-29}$ Gauss on a scale of 100 pc, the size of the largest turbulent eddy
in a virialised galaxy. Resonant amplification in preheating can lead to
primordial fields as large as $10^{-24}$ Gauss, consistent with the seed field
required for the galactic dynamo mechanism.

</DOC>
<DOC>
<DOCNO> 69054 </DOCNO>
The form factor of the transition gamma gamma * pi^0


  A simple method is used to extrapolate the form factor for the process gamma*
gamma *--->pi^0 when two virtual photons produce a pi ^0 from the region of
large spacelike photon virtualities to the experimentally accessible case when
one of the photons is real. The method is also applied to the study of the
axial anomaly and omega -rho -pi coupling and to the pion charge and charge
radius. The results compare favourably with the experimental measurements.

</DOC>
<DOC>
<DOCNO> 117306 </DOCNO>
An Estimate of the Age Distribution of Terrestrial Planets in the


  Planets like the Earth cannot form unless elements heavier than helium are
available. These heavy elements, or `metals', were not produced in the big
bang. They result from fusion inside stars and have been gradually building up
over the lifetime of the Universe. Recent observations indicate that the
presence of giant extrasolar planets at small distances from their host stars,
is strongly correlated with high metallicity of the host stars. The presence of
these close-orbiting giants is incompatible with the existence of earth-like
planets. Thus, there may be a Goldilocks selection effect: with too little
metallicity, earths are unable to form for lack of material, with too much
metallicity giant planets destroy earths. Here I quantify these effects and
obtain the probability, as a function of metallicity, for a stellar system to
harbour an earth-like planet. I combine this probability with current estimates
of the star formation rate and of the gradual build up of metals in the
Universe to obtain an estimate of the age distribution of earth-like planets in
the Universe. The analysis done here indicates that three quarters of the
earth-like planets in the Universe are older than the Earth and that their
average age is 1.8 +/- 0.9 billion years older than the Earth. If life forms
readily on earth-like planets - as suggested by the rapid appearance of life on
Earth - this analysis gives us an age distribution for life on such planets and
a rare clue about how we compare to other life which may inhabit the Universe.

</DOC>
<DOC>
<DOCNO> 100243 </DOCNO>
The Poincar\'{e} series of some special quasihomogeneous surface


  In the author's paper ''Poincar\'{e} series and monodromy of a
two-dimensional quasihomogeneous hypersurface singularity'' a relation is
proved between the Poincar\'{e} series of the coordinate algebra of a
two-dimensional quasihomogeneous isolated hypersurface singularity and the
characteristic polynomial of its monodromy operator. We study this relation for
Fuchsian singularities and show that it is connected with the mirror symmetry
of K3 surfaces and with automorphisms of the Leech lattice. We also indicate
relations between other singularities and Conway's group.

</DOC>
<DOC>
<DOCNO> 85585 </DOCNO>
Detecting Binary Black Holes With Efficient and Reliable Templates


  Detecting binary black holes in interferometer data requires an accurate
knowledge of the orbital phase evolution of the system. From the point of view
of data analysis one also needs fast algorithms to compute the templates that
will employed in searching for black hole binaries. Recently, there has been
progress on both these fronts: On the one hand, re-summation techniques have
made it possible to accelerate the convergence of poorly convergent asymptotic
post-Newtonian series and derive waveforms beyond the conventional adiabatic
approximation. We now have a waveform model that extends beyond the inspiral
regime into the plunge phase followed by the quasi-normal mode ringing. On the
other hand, explicit Fourier domain waveforms have been derived that make the
generation of waveforms fast enough so as not to be a burden on the
computational resources required in filtering the detector data. These new
developments should make it possible to efficiently and reliably search for
black hole binaries in data from first interferometers.

</DOC>
<DOC>
<DOCNO> 69987 </DOCNO>
Properties of a family of n reggeized gluon states in multicolour QCD


  A general relation between families of (n+1) gluon and n gluon eigenstates of
the BKP evolution kernels in the multicolour limit of QCD is derived. It allows
to construct an (n+1) gluon eigenstate if an n gluon eigenstate is known; this
solution is Bose symmetric and thus physical for even n. A recently found
family of odderon solutions corresponds to the particular case n=2.

</DOC>
<DOC>
<DOCNO> 116562 </DOCNO>
One topological secret of gravity and its surprises for astrophysics,


  It is shown, that the horizon (2-sphere) in fact is the central source point
(r=0) for a physical radius in Schwarzschild field and an interior of horizon
does not exists. Such topological difference between Newtonnian and
relativistic gravity leads to the observable effects. The light deflection and
the perihelion shift are examples of topological effects. A reflection on the
source of falling matter (mirror horizon effect), a hierarchy of supercompact
stars after neutron stage - multibaryon, quark, (possible) subquark and other
heavy particle stars are predicted instead of unphysical black holes. It is
shown, that the cosmological singularity and quantum field theory divergencies
are results of ignorance of the nontrivial topology of gravity near
gravitational radius and they can be simly excluded by taking into account
topology of gravity (the renormalization is a such prescription).

</DOC>
<DOC>
<DOCNO> 84502 </DOCNO>
Cosmic Strings Lens Phenomenology: Model of Poisson Energy Distribution


  We present a novel approach for investigating lens phenomenology of cosmic
strings in order to elaborate detection strategies in galaxy deep field images.
To account for the complexity of the projected energy distribution of string
networks we assume their lens effects to be similar to those of a straight
string carrying a {\em random} lineic energy distribution. In such a model we
show that, unlike the case of uniform strings, critical phenomena naturally
appear. We explore the properties of the critical lines and caustics. In
particular, assuming that the energy coherence length along the string is much
smaller than the observation scale, we succeeded in computing the total length
of critical lines per unit string length and found it to be $4/\sqrt{3} {\bf
E}(3/4)$. The length of the associated caustic lines can also be computed to be
$16/(\pi \sqrt{3}) {\bf E}(3/4)$. The picture we obtain here for the
phenomenology of cosmic string detection is clearly at variance with common
lore.

</DOC>
<DOC>
<DOCNO> 71436 </DOCNO>
Searching for T-Violating, P-Conserving New Physics with Neutrons


  The observance of parity conserving time reversal violation in light quark
systems could signal the presence of physics beyond the Standard Model. I
discuss the implications of low-energy time reversal tests for the existence of
such T-violating, P-conserving (TVPC) interactions. I argue that searches for
permanent electric dipole moments (EDM's) and direct TVPC searches provide
complementary information on P-conserving T-violation. EDM searches yield
constraints only under the assumption that parity symmetry is restored at the
scale Lambda associated with new TVPC physics. If parity remains broken at
short distances, direct searches yield the least ambiguous bounds. In the
latter case, improving the experimental precision of direct TVPC searches in
neutron beta-decay and polarized epithermal neutron transmission at the
Spallation Neutron Source could yield tighter bounds.

</DOC>
<DOC>
<DOCNO> 85015 </DOCNO>
Planck-Length Phenomenology


  This author's recent proposal of interferometric tests of
Planck-scale-related properties of space-time is here revisited from a strictly
phenomenological viewpoint. The results announced previously are rederived
using elementary dimensional considerations. The dimensional analysis is then
extended to the other two classes of experiments (observations of neutral kaons
at particle accelerators and observations of the gamma rays we detect from
distant astrophysical sources) which have been recently considered as
opportunities to explore "foamy" properties of space-time. The emerging picture
suggests that there is an objective and intuitive way to connect the
sensitivities of these three experiments with the Planck length. While in
previous studies the emphasis was always on some quantum-gravity scenario and
the analysis was always primarily aimed at showing that the chosen scenario
would leave a trace in a certain class of doable experiments, the analysis here
reported takes as starting point the experiments and, by relating in a direct
quantitative way the sensitivities to the Planck length, provides a
model-independent description of the status of Planck-length phenomenology.

</DOC>
<DOC>
<DOCNO> 84102 </DOCNO>
Reissner-Nordstr\"om-AdS black hole in the GEMS approach


  We obtain a (5+2)-dimensional global flat embedding of the (3+1)-dimensional
curved RN-AdS space. Our results include the various limiting cases of global
embedding Minkowski space (GEMS) geometries of the RN, Schwarzschild-AdS in
(5+2)-dimensions, Schwarzschild in (5+1)-dimensions, purely charged space, and
universal covering space of AdS in (4+1)-dimensions, through the successive
truncation procedure of parameters in the original curved space.

</DOC>
<DOC>
<DOCNO> 151221 </DOCNO>
Constraints on Brane-Localized Gravity


  In this paper we explore some general aspects of the embeddings associated
with brane-localized gravity. In particular we show that the consistency of
such embeddings can require (or impose) very specific relations between all the
involved bulk and brane matter source parameters. We specifically explore the
embeddings of 3-branes with non-zero spatial 3-curvature $k$ into 5-dimensional
spacetime bulks, and show that for such embeddings, a 5-dimensional bulk
cosmological constant is not able to produce the exponential suppression of the
geometry thought necessary to localize gravity to the brane.

</DOC>
<DOC>
<DOCNO> 10965 </DOCNO>
Low frequency response of a collectively pinned vortex manifold


  A low frequency dynamic response of a vortex manifold in type-II
superconductor can be associated with thermally activated tunneling of large
portions of the manifold between pairs of metastable states (two-level
systems). We suggest that statistical properties of these states can be
verified by using the same approach for the analysis of thermal fluctuations
the behaviour of which is well known. We find the form of the response for the
general case of vortex manifold with non-dispersive elastic moduli and for the
case of thin superconducting film for which the compressibility modulus is
always non-local.

</DOC>
<DOC>
<DOCNO> 85428 </DOCNO>
Radiation reaction and the self-force for a point mass in general


  A point particle of mass m moving on a geodesic creates a perturbation h, of
the spacetime metric g, that diverges at the particle. Simple expressions are
given for the singular m/r part of h and its quadrupole distortion caused by
the spacetime. Subtracting these from h leaves a remainder h^R that is C^1. The
self-force on the particle from its own gravitational field corrects the
worldline at O(m) to be a geodesic of g+h^R. For the case that the particle is
a small non-rotating black hole, an approximate solution to the Einstein
equations is given with error of O(m^2) as m approaches 0.

</DOC>
<DOC>
<DOCNO> 100088 </DOCNO>
Connected components of real double Bruhat cells


  Double Bruhat cells in a semisimple group are intersections of cells in two
Bruhat decompositions corresponding to two opposite Borel subgroups. They form
a geometric framework for the study of total positivity in semisimple groups;
they are also closely related to symplectic leaves in the corresponding
Poisson-Lie groups. The term "cells" might be misleading because their topology
can be quite non-trivial. As a first step towards understanding this topology,
we enumerate the connected components of real double Bruhat cells. This result
extends (from the simply-laced case to the general one) and proves the
conjecture made in a joint work with B.Shapiro-M.Shapiro-A.Vainshtein; it also
extends earlier work by B.Shapiro-M.Shapiro-A.Vainshtein and K.Rietsch.

</DOC>
<DOC>
<DOCNO> 119565 </DOCNO>
Was the Whirlpool (M51) a Spiral Galaxy before the Encounter with the


  Using the B-I color index in the radial photometry of M51, applied to defined
azimuthal sectors, we reveals asymmetries in the shape of the density pattern
of the galactic arms. The anomalous shape is present only in the side close to
the companion and not in the far side. Two more non-interacting check-spirals
do not show similar behaviour. The anomalous sawtooth-like shape is similar to
that produced by a progressive wave propagating in a preexisting density
pattern. In this hypothesis we have to conclude that the galaxy M51 could be a
spiral galaxy formerly, i.e. before the encounter with the companion.

</DOC>
<DOC>
<DOCNO> 101887 </DOCNO>
A numerical method for solving some nonlinear problems


  A nonlinear equation in a Banach space is written as a linear equation with a
linear operator depending on the unknown solution. This method, which we call a
global linearization method, differs essentially from the local linearization
methods of the Newton-type.
  Inverting the above linear operator by the methods known for linear operators
one gets an equation which sometimes is much better for numerical solution than
the original one. Some theorems about convergence of the proposed iterative
process for solving the transformed equation are given. Examples of
applications are considered.

</DOC>
<DOC>
<DOCNO> 152188 </DOCNO>
Wilson loops in strongly coupled noncommutative gauge theories


  We discuss Wilson loop averages in 4-dimensional non-commutative
superYang-Mills theory using the dual supergravity description. We postulate
that the Wilson loops are located at the mimimum length scale $R$ in the fifth
radial coordinate. We find that they exhibit a crossover from Coulomb type of
behaviour for large loops, for which non-commutativity is unimportant, to area
law for small loops, for which non-commutativity effects are large. The string
tension, which can be read off from the area law, is controlled by the
non-commutativity scale. The crossover itself, however, appears to involve
loops of size of order $R$ which is much larger than the non-commutativity
scale. The existence of the area law in non-commutative super Yang-Mills theory
which persists up to a large crossover length scale provides further evidence
for connection to an underlying string theory.

</DOC>
<DOC>
<DOCNO> 99302 </DOCNO>
Any 3-manifold 1-dominates at most finitely many geometric 3-manifolds


  In this paper, we proved that any closed orientable 3-manifold 1-dominates at
most finitely many geometric 3-manifolds.

</DOC>
<DOC>
<DOCNO> 11654 </DOCNO>
Electronic and Magnetic Properties of Electron-doped Superconductor,


  Temperature-dependent magnetization (M(T)) and specific heat (C_p(T))
measurements were carried out on single crystal Sm_{1.85}Ce_{0.15}CuO_{4-delta}
(T_c = 16.5 K). The magnetic anisotropy in the static susceptibility, chi
{equiv} M/H, is apparent not only in its magnitude but also in its temperature
dependence, with chi_{perp} for H{perp}c larger than chi_{parallel} for
H{parallel}c. For both field orientations, chi does not follow the Curie-Weiss
behavior due to the small energy gap of the J = 7/2 multiplet above the J = 5/2
ground-state multiplet. However, with increasing temperature, chi_{parallel}(T)
exhibits a broad minimum near 100 K and then a slow increase while
chi_{perp}(T) shows a monotonic decrease. A sharp peak in C_p(T) at 4.7 K
manifests an antiferromagnetic ordering. The electronic contribution, gamma, to
C_p(T) is estimated to be gamma = 103.2 (7) mJ/moleSmK^2. The entropy
associated with the magnetic ordering is much smaller than Rln2, where R is the
gas constant, which is usually expected for the doublet ground state of
Sm^{+3}. The unusual magnetic and electronic properties evident in M(T) and
C_p(T) are probably due to a strong anisotropic interaction between conduction
electrons and localized electrons at Sm^{+3} sites.

</DOC>
<DOC>
<DOCNO> 118605 </DOCNO>
Cepheid variables in the LMC cluster NGC 1866. I. New BVRI CCD


  We report BV(RI)c CCD photometric data for a group of seven Cepheid variables
in the young, rich cluster NGC 1866 in the Large Magellanic Cloud. The
photometry was obtained as part of a program to determine accurate distances to
these Cepheids by means of the infrared surface brightness technique, and to
improve the LMC Cepheid database for constructing Cepheid PL and PLC relations.
Using the new data together with data from the literature, we have determined
improved periods for all variables. For five fundamental mode pulsators, the
light curves are now of excellent quality and will lead to accurate distance
and radius determinations once complete infrared light curves and radial
velocity curves for these variables become available.

</DOC>
<DOC>
<DOCNO> 118051 </DOCNO>
Hot Stars and Cool Clouds: The Photodissociation Region M16


  We present high-resolution spectroscopy and images of a photodissociation
region (PDR) in M16 obtained during commissioning of NIRSPEC on the Keck II
telescope. PDRs play a significant role in regulating star formation, and M16
offers the opportunity to examine the physical processes of a PDR in detail. We
simultaneously observe both the molecular and ionized phases of the PDR and
resolve the spatial and kinematic differences between them. The most prominent
regions of the PDR are viewed edge-on. Fluorescent emission from nearby stars
is the primary excitation source, although collisions also preferentially
populate the lowest vibrational levels of H2. Variations in density-sensitive
emission line ratios demonstrate that the molecular cloud is clumpy, with an
average density n = 3x10^5 cm^(-3). We measure the kinetic temperature of the
molecular region directly and find T_H2 = 930 K. The observed density,
temperature, and UV flux imply a photoelectric heating efficiency of 4%. In the
ionized region, n_i=5x10^3 cm^(-3) and T_HII = 9500 K. In the brightest regions
of the PDR, the recombination line widths include a non-thermal component,
which we attribute to viewing geometry.

</DOC>
<DOC>
<DOCNO> 67806 </DOCNO>
The triple Higgs self-coupling at future e+e- colliders: a


  The experimental reconstruction of the Higgs self-energy potential is
essential to a verification of the Higgs boson's role in spontaneous
electroweak symmetry breaking. The first step towards this goal, the
measurement of the triple Higgs self-coupling, can possibly be accomplished at
the next generation of linear colliders. Here we present a background study of
the most promising channel, double Higgs-strahlung off a Z boson, e+e- -> HHZ,
with the subsequent decay H -> b bbar, and evaluate the feasibility of its
measurement.

</DOC>
<DOC>
<DOCNO> 8840 </DOCNO>
Self organization in a minority game: the role of memory and a


  A minority game whose strategies are given by probabilities p, is replaced by
a 'simplified' version that makes no use of memories at all. Numerical results
show that the corresponding distribution functions are indistinguishable. A
related approach, using a random walk formulation, allows us to identify the
origin of correlations and self organization in the model, and to understand
their disappearence for a different strategy's update rule, as pointed out in a
previous work

</DOC>
<DOC>
<DOCNO> 9657 </DOCNO>
Characteristic polynomials of random matrices at edge singularities


  We have discussed earlier the correlation functions of the random variables
$\det(\la-X)$ in which $X$ is a random matrix. In particular the moments of the
distribution of these random variables are universal functions, when measured
in the appropriate units of the level spacing. When the $\la$'s, instead of
belonging to the bulk of the spectrum, approach the edge, a cross-over takes
place to an Airy or to a Bessel problem, and we consider here these modified
classes of universality.
  Furthermore, when an external matrix source is added to the probability
distribution of $X$, various new phenomenons may occur and one can tune the
spectrum of this source matrix to new critical points. Again there are
remarkably simple formulae for arbitrary source matrices, which allow us to
compute the moments of the characteristic polynomials in these cases as well.

</DOC>
<DOC>
<DOCNO> 116401 </DOCNO>
Hierarchic model of consciousness: from molecular Bose condensation to


  Hierarchic Model of Consciousness (HMC), proposed, is based on Hierarchic
theory of matter, developed by the author
(physics/0003044). In accordance to HMC, each specific kind
of neuron ensembles excitation - corresponds to hierarchical system of
three-dimensional (3D) standing waves of different kind: thermal de Broglie
waves (waves B); electromagnetic (IR) waves; acoustic waves;
vibro-gravitational waves, excited by coherent translational and librational
oscillations of water molecules in microtubules (MTs). We assume the existence
of following reactions after excitation of neuron ensemble: a) 'pulsation' of
the volume and geometry of neurons bodies as a result of [gel-sol] transition
due to actin disassembly; c) correlated MTs re-orientations, stimulated by
their distant exchange interaction, mediated by coherent IR photons; d)
redistribution of ionic channels activity and synaptic contacts on the surface
of the 'tuned' nerve cells bodies, dependent on volume/geometry of cells.

</DOC>
<DOC>
<DOCNO> 67918 </DOCNO>
Enhanced Global Symmetry Constraints on epsilon Terms


  Recently it has been proposed that the physical spectrum of a vector-like
gauge field theory may exhibit an enhanced global symmetry near a
chiral/conformal phase transition. The new symmetry is related to the
possibility, supported by various investigations, that a parity-doubled
spectrum develops as the number of fermions Nf is increased to a critical value
above which it is expected that the symmetric phase is restored.
 We show that parity-doubling together with the associated enhanced global
symmetry severely constrains the epsilon terms of the effective Lagrangian
involving Goldstone bosons as well as massive spin-1 particles. We extend our
analysis to underlying fermions in pseudo-real representations of the gauge
group.

</DOC>
<DOC>
<DOCNO> 101656 </DOCNO>
Classical versions of q-Gaussian processes: conditional moments and


  We show that classical processes corresponding to operators what satisfy a
q-commutative relation have linear regressions and quadratic conditional
variances. From this we deduce that Bell's inequality for their covariances can
be extended from q=-1 to the entire range -1<q<1.

</DOC>
<DOC>
<DOCNO> 122891 </DOCNO>
ATCA search for 21 cm emission from a candidate damped Ly-$\alpha$


  We report a deep search for 21 cm emission/absorption from the $z \sim 0.101$
candidate damped Lyman-$\alpha$ system towards PKS 0439-433, using the
Australia Telescope Compact Array (ATCA). The spectrum shows a weak absorption
feature --- at the $3.3 \sigma$ level --- which yields a lower limit of 730 K
on the spin temperature of the system. No HI emission was detected: the
$3\sigma$ upper limit on the HI mass of the absorber is $2.25 \times 10^9
M_{\odot}$, for a velocity spread of $\sim 70$ km s$^{-1}$. The low HI mass and
the high spin temperature seem to rule out the possibility that the absorber is
a large gas-rich spiral galaxy.

</DOC>
<DOC>
<DOCNO> 119053 </DOCNO>
Secondary Cosmic Muon Angular Distributions with High Statistics


  Project GRAND preents a map in right ascension and declination for single
cosmic secondary tracks which have been identified as muons. These muons are
measured in stations of proportional wire chambers (PWCs) which have a mean
angular resolution of 0.26 deg. A 50 mm steel plate interspersed with the PWCs
is used to distinguish muons from electrons. Two years of data are accumulated
in a map of right ascension and declination which covers all of the northern
hemisphere and a small portion of the southern hemisphere. The total number of
muon tracks in this data sample are 40 billion. Significant large angular
structure is found in this map; the deviations from average are small compared
to the average, but because of the high statistics, the deviations from average
are statistically significant to many standard deviations. Systematic effects
in the data are minimized by averaging over this two year period. These results
are similar to those obtained in previous data.

</DOC>
<DOC>
<DOCNO> 12958 </DOCNO>
A New Approach to Doped Mott Insulators


  We describe a new microscopic approach for analyzing interacting electron
systems with local moments or, in principle, any local order parameter. We
specialize attention to the doped Mott insulator phase of the Hubbard model,
where standard weak-coupling perturbation methods fail. A rotationally
invariant Stratonovich-Hubbard field is introduced to decouple the static spin
components of the interaction at each site. Charge degrees of freedom are then
treated by ``slave'' Hartree-Fock in the presence of a spatially varying random
spin field. The effective action reduces to a classical Heisenberg model at
half filling, insuring that the system has (i) finite-range order at T>0 with
an exponentially diverging correlation length and (ii) a one-electron
Mott-Hubbard gap in the presence of disorder. Away from half-filling properties
are determined by strongly non-Gaussian fluctuations in the amplitude and
orientation of the local spin fields. The saddle point equations of the theory
at zero temperature reduce to inhomogeneous Hartree-Fock, so that disordering
of domain walls at finite temperature is in principle included. We present
preliminary small system results for the intermediate and large interaction
regimes obtained by Monte Carlo simulation of random spin field configurations.

</DOC>
<DOC>
<DOCNO> 67670 </DOCNO>
Contribution of the direct decay $\phi\to\pi^+ \pi^- \gamma$ to the


  The potential of DAPHNE to explore direct radiative decay $\phi \to \pi^+
\pi^- \gamma$ is studied in detail. Predictions of different theoretical models
for this decay are compared. We find that it should be possible to discriminate
between these models at DAPHNE in one year, even assuming a relatively low
luminosity ${\cal{L}} = 10^{31} {\rm cm}^{-2} {\rm sec^{-1}}$. The influence of
the decay $\phi \to \pi^+ \pi^- \gamma$ on the measurement of total cross
section $\sigma(e^+e^- \to {\rm hadrons})$ by tagging a photon in the reaction
$e^+e^- \to \pi^+\pi^- \gamma$ is also discussed.

</DOC>
<DOC>
<DOCNO> 150395 </DOCNO>
Open strings, Born--Infeld action and the heat kernel


  In the derivation of the Born-Infeld action for the case with a nontrivial
boundary of the string world sheet the appearance of a new term changes the
conformal anomaly. This may have many consequences, especially also in the
study of generalized interacting brane systems.

</DOC>
<DOC>
<DOCNO> 150827 </DOCNO>
Near-extremal correlators and vanishing supergravity couplings in


  We study near-extremal n-point correlation functions of chiral primary
operators, in which the maximal scale dimension k is related to the others by
k=\sum_i k_i-m with m equal to or smaller than n-3. Through order g^2 in field
theory, we show that these correlators are simple sums of terms each of which
factors into products of lower-point correlators. Terms which contain only
factors of two- and three-point functions are not renormalized, but other terms
have non-vanishing order g^2 corrections.
  We then show that the contributing AdS exchange diagrams neatly match this
factored structure. In particular, for n=4,5 precise agreement in form and
coefficient is established between supergravity and the non-renormalized
factored terms from field theory. On the other hand, contact diagrams in
supergravity would produce a non-factored structure. This leads us to
conjecture that the corresponding bulk couplings vanish, so as to achieve full
agreement between the structure of these correlators in supergravity and
weak-coupling field theory.

</DOC>
<DOC>
<DOCNO> 121801 </DOCNO>
Morphological Properties of PPNs: Mid-IR and HST Imaging Surveys


  We will review our mid-infrared and HST imaging surveys of the circumstellar
dust shells of proto-planetary nebulae. While optical imaging indirectly probes
the dust distribution via dust-scattered starlight, mid-IR imaging directly
maps the distribution of warm dust grains. Both imaging surveys revealed
preferencially axisymmetric nature of PPN dust shells, suggesting that
axisymmetry in planetary nebulae sets in by the end of the asymptotic giant
branch phase, most likely by axisymmetric superwind mass loss. Moreover, both
surveys yielded two morphological classes which have one-to-one correspondence
between the two surveys, indicating that the optical depth of circumstellar
dust shells plays an equally important role as the inclination angle in
determining the morphology of the PPN shells.

</DOC>
<DOC>
<DOCNO> 100968 </DOCNO>
Oriented Quantum Algebras and Invariants of Knots and Links


  In GT/0006019 oriented quantum algebras were motivated and introduced in a
natural categorical setting. Invariants of knots and links can be computed from
oriented quantum algebras, and this includes the Reshetikhin-Turaev theory for
Ribbon Hopf algebras. Here we continue the study of oriented quantum algebras
from a more algebraic perspective, and develop a more detailed theory for them
and their associated invariants.

</DOC>
<DOC>
<DOCNO> 40190 </DOCNO>
Supernova Neutrino Detection


  World-wide, several detectors currently running or nearing completion are
sensitive to a core collapse supernova neutrino signal in the Galaxy. I will
briefly describe the nature of the neutrino signal and then survey current and
future detection techniques. I will also explore what physics and astrophysics
we can learn from the next Galactic core collapse.

</DOC>
<DOC>
<DOCNO> 80833 </DOCNO>
P-vortices and Drama of Gribov Copies


  We present results of the careful study of the Gribov copies problem in SU(2)
lattice gauge theory for the direct maximal center projection widely used in
confinement studies. Applying simulated annealing algorithm we demonstrate that
this problem is more severe than it was thought before. The projected (gauge
noninvariant) string tension is not in the agreement with the physical string
tension. We do not find any indications that P-vortices reproduce the full
SU(2) string tension neither in the infinite volume limit nor in the continuum
limit.

</DOC>
<DOC>
<DOCNO> 71918 </DOCNO>
Pomeron contribution to Spin-flip


  The pp polarization data confirm the presence of a diffractive-like (Pomeron)
contribution in the spin-flip amplitude. The extrapolation to RHIC energies
does not appear very promising.

</DOC>
<DOC>
<DOCNO> 170608 </DOCNO>
Possible peculiarities of synchrotron radiation in a strong magnetic


  Relativistic quantum effects on physical observables of scalar charged
particles are studied. Possible peculiarities of their behavior that can be
verified in an experiment can confirm several fundamental conceptions of
quantum mechanics. For observables independent of charge variable, we propose
relativistic Wigner function formalism that contains explicitly the measurement
device frame. This approach can provide the description of charged particles
gas (plasma). It differs from the traditional one but is consistent with the
Copenhagen interpretation of quantum mechanics. The effects that are connected
with this approach can be observed in astrophysical objects - neutron stars.

</DOC>
<DOC>
<DOCNO> 9946 </DOCNO>
Phases of a Stack of Membranes at Large-d


  The phase diagram of a stack of tensionless membranes with nonlinear
curvature energy and vertical harmonic interaction is calculated exactly in a
large number of dimensions of configuration space. At low temperatures, the
system forms a lamellar phase with spontaneously broken translational symmetry
in the vertical direction. At a critical temperature, the stack disorders
vertically in a melting-like transition. The critical temperature is determined
as a function of the interlayer separation l.

</DOC>
<DOC>
<DOCNO> 10864 </DOCNO>
Josephson Effect in Metal - Polyimide - Metal Sandwich Structures


  We have observed that thin films of amorphous polyimide placed between two
metallic electrodes become highly conducting with no applied electric field,
and at a low pressure which was necessary only to achieve reliable electrical
contact with the metallic electrodes. We observed for the first time a
Josephson effect in a sandwich of a superconductor - polyimide film -
superconductor.

</DOC>
<DOC>
<DOCNO> 122333 </DOCNO>
Constraining the black hole mass and accretion rate in the narrow-line


  We present a comprehensive study of the spectrum of the narrow-line Seyfert 1
galaxy RE J1034+396, summarizing the information obtained from the optical to
X-rays with observations from the William Herschel 4.2m Telescope (WHT), the
Hubble Space Telescope, the Extreme UltraViolet Explorer, ROSAT, ASCA and
BeppoSAX. The BeppoSAX spectra reveal a soft component which is
well-represented by two blackbodies with kT of about 60 eV and 160 eV,
mimicking that expected from a hot, optically-thick accretion disc around a
low-mass black hole. This is borne out by our modeling of the optical to X-ray
nuclear continuum, which constrains the physical parameters of a NLS1 for the
first time. The models demonstrate that RE J1034+396 is likely to be a system
with a nearly edge-on accretion disk (60 to 75 degrees from the disk axis),
accreting at nearly Eddington rates (0.3 to 0.7 L_edd) onto a low mass (about 2
million solar masses) black hole (abridged).

</DOC>
<DOC>
<DOCNO> 151697 </DOCNO>
Diffeomorphisms, Anomalies and the Fefferman-Graham Ambiguity


  Using the Weyl transfomations induced by diffeomorphisms we set up a
cohomological problem for the Fefferman-Graham coefficients. The
cohomologically nontrivial solutions remove the ambiguity and give the nonlocal
terms in the effective action responsible for the trace anomalies.

</DOC>
<DOC>
<DOCNO> 12319 </DOCNO>
Swelling kinetics of the onion phase


  A theory is presented for the behavior of an array of multi-lamellar vesicles
(the onion phase) upon addition of solvent. A unique feature of this system is
the possibility to sustain pressure gradients by tension in the lamellae.
Tension enables the onions to remain stable beyond the unbinding point of a
flat lamellar stack. The model accounts for various concentration profiles and
interfaces developing in the onion as it swells. In particular, densely packed
`onion cores' are shown to appear, as observed in experiments. The formation of
interfaces and onion cores may represent an unusual example of stabilization of
curved interfaces in confined geometry.

</DOC>
<DOC>
<DOCNO> 40149 </DOCNO>
New Measurements of Nucleon Structure Functions from the CCFR/NuTeV


  We report on the extraction of the structure functions F_2 and Delta xF_3 =
xF_3nu-xF_3nubar from CCFR neutrino-Fe and antineutrino-Fe differential cross
sections. The extraction is performed in a physics model independent (PMI) way.
This first measurement for Delta xF_3, which is useful in testing models of
heavy charm production, is higher than current theoretical predictions. The F_2
(PMI) values measured in neutrino and muon scattering are in good agreement
with the predictions of Next to Leading Order PDFs (using massive charm
production schemes), thus resolving the long-standing discrepancy between the
two sets of data.

</DOC>
<DOC>
<DOCNO> 122416 </DOCNO>
Probing Galaxy Formation with High Energy Gamma-Rays


  We discuss how measurements of the absorption of $\gamma$-rays from GeV to
TeV energies via pair production on the extragalactic background light (EBL)
can probe important issues in galaxy formation. We use semi-analytic models
(SAMs) of galaxy formation, set within the hierarchical structure formation
scenario, to obtain predictions of the EBL for 0.1-1000$\mu$m. SAMs incorporate
simplified physical treatments of the key processes of galaxy formation ---
including gravitational collapse and merging of dark matter halos, gas cooling
and dissipation, star formation, supernova feedback and metal production ---
and have been shown to reproduce key observations at low and high redshift.
Here we also introduce improved modelling of the spectral energy distributions
in the mid-to-far-IR arising from emission by dust grains. Assuming a flat
\lcdm cosmology with $\Omega_m=0.3$ and Hubble parameter $h=0.65$, we
investigate the consequences of variations in input assumptions such as the
stellar initial mass function (IMF) and the efficiency of converting cold gas
into stars. We conclude that observational studies of the absorption of
$\gamma$-rays with energies from 10s of Gev to 10s of TeV will help to
determine the EBL, and also help to explain its origin by constraining some of
the most uncertain features of galaxy formation theory, including the IMF, the
history of star formation, and the reprocessing of light by dust.

</DOC>
<DOC>
<DOCNO> 118846 </DOCNO>
Redshifts For 220 BATSE Gamma-Ray Bursts Determined by Variability and


  We show that the time variability of a gamma-ray burst (GRB) appears to be
correlated with the absolute luminosity of the burst: smooth bursts are
intrinsically less luminous. This Cepheid-like relationship can be used to
determine the redshift of a GRB from parameters measured solely at gamma-ray
energies. The relationship is based on only seven events at present and needs
to be further confirmed with more events. We present the details of converting
GRB observables to luminosities and redshifts for 220 bright, long GRBs from
the Burst and Transient Source Experiment (BATSE) and explore the cosmological
consequences. In particular, we derive the GRB rate as a function of $z$
without assuming either a luminosity function or that the GRB rate follows the
star formation rate (SFR). We find that the GRB formation rate scales as
(1+z)^{3.3 \pm 0.3}. The observations used to derive the SFR can be strongly
affected by dust for z > 2 whereas GRB observations are not. If GRBs trace star
formation, then our results indicate that the SFR does not peak at z\sim 2 but
instead continues to increase until z \sim 10. We have used the burst formation
rate to correct the observed GRB luminosity function for the incompleteness due
to the detection threshold, resulting in a luminosity function with a power law
index of \sim -2.3 that slightly rolls over at low luminosities. The reality of
our variability--luminosity relationship requires confirmation but, if valid,
will provide a powerful tool for studying both GRBs and the early universe.

</DOC>
<DOC>
<DOCNO> 9070 </DOCNO>
On the genealogy of a population of biparental individuals


  If one goes backward in time, the number of ancestors of an individual
doubles at each generation. This exponential growth very quickly exceeds the
population size, when this size is finite. As a consequence, the ancestors of a
given individual cannot be all different and most remote ancestors are repeated
many times in any genealogical tree. The statistical properties of these
repetitions in genealogical trees of individuals for a panmictic closed
population of constant size N can be calculated. We show that the distribution
of the repetitions of ancestors reaches a stationary shape after a small number
Gc ~ log N of generations in the past, that only about 80% of the ancestral
population belongs to the tree (due to coalescence of branches), and that two
trees for individuals in the same population become identical after Gc
generations have elapsed. Our analysis is easy to extend to the case of
exponentially growing population.

</DOC>
<DOC>
<DOCNO> 99603 </DOCNO>
Lectures on Factorization of Birational Maps


  This is an expanded version of the notes for the lectures given by the author
at RIMS in the summer of 1999 to give a detailed account of the proof for the
(weak) factorization theorem of birational maps by
Abramovich-Karu-Matsuki-W{\l}odarczyk.

</DOC>
<DOC>
<DOCNO> 120627 </DOCNO>
Dynamical masses, time-scales, and evolution of star clusters


  This review discusses (i) dynamical methods for determining the masses of
Galactic and extragalactic star clusters, (ii) dynamical processes and their
time-scales for the evolution of clusters, including evaporation, mass
segregation, core collapse, tidal shocks, dynamical friction and merging. These
processes lead to significant evolution of globular cluster systems after their
formation.

</DOC>
<DOC>
<DOCNO> 122494 </DOCNO>
SDSS-RASS: Next Generation of Cluster-Finding Algorithms


  We outline here the next generation of cluster-finding algorithms. We show
how advances in Computer Science and Statistics have helped develop robust,
fast algorithms for finding clusters of galaxies in large multi-dimensional
astronomical databases like the Sloan Digital Sky Survey (SDSS). Specifically,
this paper presents four new advances: (1) A new semi-parametric algorithm -
nicknamed ``C4'' - for jointly finding clusters of galaxies in the SDSS and
ROSAT All-Sky Survey databases; (2) The introduction of the False Discovery
Rate into Astronomy; (3) The role of kernel shape in optimizing cluster
detection; (4) A new determination of the X-ray Cluster Luminosity Function
which has bearing on the existence of a ``deficit'' of high redshift, high
luminosity clusters. This research is part of our ``Computational
AstroStatistics'' collaboration (see Nichol et al. 2000) and the algorithms and
techniques discussed herein will form part of the ``Virtual Observatory''
analysis toolkit.

</DOC>
<DOC>
<DOCNO> 12552 </DOCNO>
Real-time correlation functions from imaginary-time evolution


  The problem of calculating real-time correlation functions is formulated in
terms of an imaginary-time partial differential equation. The latter is solved
analytically for the perturbed harmonic oscillator and compared with the known
exact result. The first order approximation for the short-time propagator is
derived and used for numerical solution of the equation by a Monte Carlo
integration. In general, the method provides a reformulation of the dynamic
sign problem, and is applicable to any two-time correlation function including
single-particle, density-density, current-current, spin-spin, and others. The
prospects of extending the technique onto multi-dimensional problems are
discussed.

</DOC>
<DOC>
<DOCNO> 84438 </DOCNO>
Unexpectedly large surface gravities for acoustic horizons?


  Acoustic black holes are fluid dynamic analogs of general relativistic black
holes, wherein the behaviour of sound waves in a moving fluid acts as an analog
for scalar fields propagating in a gravitational background. Acoustic horizons
possess many of the properties more normally associated with the event horizons
of general relativity, up to and including Hawking radiation. They have
received much attention because it would seem to be much easier to
experimentally create an acoustic horizon than to create an event horizon. We
wish to point out some potential difficulties (and opportunities) in actually
setting up an experiment that possesses an acoustic horizon. We show that in
zero-viscosity, stationary fluid flow with generic boundary conditions, the
creation of an acoustic horizon is accompanied by a formally infinite ``surface
gravity'', and a formally infinite Hawking flux. Only by applying a suitable
non-constant external body force, and for very specific boundary conditions on
the flow, can these quantities be kept finite. This problem is ameliorated in
more realistic models of the fluid. For instance, adding viscosity always makes
the Hawking flux finite, but greatly complicates the behaviour of the acoustic
radiation --- viscosity is tantamount to explicitly breaking ``acoustic Lorentz
invariance''. Thus, this issue represents both a difficulty and an opportunity
--- acoustic horizons may be somewhat more difficult to form than naively
envisaged, but if formed, they may be much easier to detect than one would at
first suppose.

</DOC>
<DOC>
<DOCNO> 117602 </DOCNO>
Optical Identification of the ASCA Large Sky Survey


  We present results of optical identification of the X-ray sources detected in
the ASCA Large Sky Survey. Optical spectroscopic observations were done for 34
X-ray sources which were detected with the SIS in the 2-7 keV band above 3.5
sigma. The sources are identified with 30 AGNs, 2 clusters of galaxies, and 1
galactic star. Only 1 source is still unidentified. The flux limit of the
sample corresponds to 1 x 10^{-13} erg s^{-1} cm^{-2} in the 2-10 keV band.
  Based on the sample, the paper discusses optical and X-ray spectral
properties of the AGNs, contribution of the sources to the Cosmic X-ray
Background, and redshift and luminosity distributions of the AGNs. An
interesting result is that the redshift distribution of the AGNs suggests a
deficiency of high-redshift (0.5 < z < 2) and luminous (Lx(2-10 keV) > 10^{44}
erg s^{-1}) absorbed narrow-line AGNs (so called type 2 QSOs).

</DOC>
<DOC>
<DOCNO> 70061 </DOCNO>
Calculation of fermionic two-loop contributions to muon decay


  The computation of the correction \Delta r in the W-Z mass correlation,
derived from muon decay, is described at the two-loop level in the Standard
Model. Technical aspects which become relevant at this level are studied, e.g.
gauge-parameter independent mass renormalization, ghost-sector renormalization
and the treatment of \gamma_5. Exact results for \Delta r and the W mass
prediction including O(\alpha^2) corrections with fermion loops are presented
and compared with previous results of a next-to-leading order expansion in the
top-quark mass.

</DOC>
<DOC>
<DOCNO> 68704 </DOCNO>
A fast algorithm for generating a uniform distribution inside a


  We describe a uniformly fast algorithm for generating points \vec{x}
uniformly in a hypercube with the restriction that the difference between each
pair of coordinates is bounded. We discuss the quality of the algorithm in the
sense of its usage of pseudo-random source numbers, and present an interesting
result on the correlation between the coordinates.

</DOC>
<DOC>
<DOCNO> 101888 </DOCNO>
Extrema of p-energy functional on a Finsler manifold


  The paper analyses the extrema of p-energy functional on a Finsler space with
constant curvature.

</DOC>
<DOC>
<DOCNO> 70925 </DOCNO>
Thermalisation after inflation


  During (re)heating of the universe after inflation, the relativistic decay
products of the inflaton field $\phi$ must lose energy and additional particles
must be produced to attain a thermalised state at a temperature $T_{\reh}$. We
estimate the rate of energy loss via elastic and inelastic scattering
interactions. Elastic scattering is an inefficient energy loss mechanism so
inelastic processes, although higher order in the coupling $\alpha$, can be
faster because more energy is transfered. The timescale to produce a particle
number density of ${\cal O}(T_{\reh}^3)$ is the inelastic energy loss
timescale, $\sim(\alpha^3 n_\phi/T_{\reh}^2)^{-1}$.

</DOC>
<DOC>
<DOCNO> 150334 </DOCNO>
Running Couplings in Hamiltonians


  We describe key elements of the perturbative similarity renormalization group
procedure for Hamiltonians using two, third-order examples: phi^3 interaction
term in the Hamiltonian of scalar field theory in 6 dimensions and triple-gluon
vertex counterterm in the Hamiltonian of QCD in 4 dimensions. These examples
provide insight into asymptotic freedom in Hamiltonian approach to quantum
field theory. The renormalization group procedure also suggests how one may
obtain ultraviolet-finite effective Schr\"odinger equations that correspond to
the asymptotically free theories, including transition from quark and gluon to
hadronic degrees of freedom in case of strong interactions. The dynamics is
invariant under boosts and allows simultaneous analysis of bound state
structure in the rest and infinite momentum frames.

</DOC>
<DOC>
<DOCNO> 117896 </DOCNO>
Emission-Line Properties of 3CR Radio Galaxies III: Origins and


  We present the results of an analysis of the large scale velocity fields of
the ionized gas associated with powerful radio galaxies. Long-slit spectra of
52 objects provide a sample of resolved velocities that span a wide range of
redshifts, radio and emission-line luminosities. Line widths reaching 1000 km/s
and resolved velocity fields with amplitudes of up 1500 km/ s are found on
scales from 10 to 100 kpc in the environments of radio galaxies at redshifts
larger than 0.5. The global velocities and FWHM are of comparable amplitudes in
the FRII sources, while the FRI sources have FWHM values that are larger than
their resolved velocity fields. We find evidence for systematically larger line
widths and velocity field amplitudes at z > 0.6. Several of the largest
amplitude systems contain two galaxies with small projected separations. All of
the > 1000 km/s systems occur in objects at z > 0.6 and all have comparable
radio and [OII] sizes. There is a weak correlation of off-nuclear line widths
and velocity field with the ratio of the radio and emission-line sizes, but it
is of low statistical significance and there is a very large dispersion. The
change in properties at redshifts above z ~ 0.6 could reflect a difference in
environments of the host galaxies, with the hosts inhabiting higher density
regions with increasing redshift. The mass of ionized gas and the apparent
enclosed dynamical mass are correllated and both increase steeply with redshift
and/or radio power.

</DOC>
<DOC>
<DOCNO> 117867 </DOCNO>
Do AGB Stars Differ Chemically from RGB Stars in Globular Clusters?


  Recent improvements in globular cluster colour-magnitude diagrams, coupled
with an increase in large-sample spectroscopic abundance studies of cluster
giants, finally allow some attempts at a statistically meaningful comparison of
the chemical compositions of red giant branch (RGB) and asymptotic branch (AGB)
cluster stars. We review some of the extant data here, concluding that in a few
clusters the AGB stars show on average smaller amounts of high-temperature
proton-capture synthesis products (low oxygen, high sodium and aluminum) at
their surfaces than do the first-ascent RGB stars. This suggests that those RGB
stars with envelopes that have been enriched with proton-capture material also
have high helium contents. Such stars after the He-flash then take up residence
on the bluest parts of the horizontal branch (as a consequence of their high
envelope helium), probably never to return to the AGB during subsequent
evolutionary stages.

</DOC>
<DOC>
<DOCNO> 13054 </DOCNO>
The second law of Thermodynamics as a theorem in quantum mechanics


  We treat a quantum mechanical system with certain general properties which
are expected to be common in macroscopic quantum systems. Starting from a PURE
initial state (which may not describe an equilibrium) in which energy is mildly
concentrated at a single value, we consider a time evolution determined by a
time-dependent Hamiltonian as a model of an adiabatic operation in
thermodynamics. We take a family of operations with the same procedure and
various ``waiting times.'' Then the Minimum Work Principle is rigorously proved
for almost all choices of the waiting time.

</DOC>
<DOC>
<DOCNO> 11145 </DOCNO>
The mean free path for electron conduction in metallic fullerenes


  We calculate the electrical resistivity due to electron-phonon scattering for
a model of A3C60 (A= K, Rb), using an essentially exact quantum Monte-Carlo
calculation. In agreement with experiment, we obtain exceptionally large
metallic resistivities at large temperatures T. This illustrates that the
apparent mean free path can be much shorter than the separation of the
molecules. An interpretation of this result is given. The calculation also
explains the linear behavior in T at small T.

</DOC>
<DOC>
<DOCNO> 85067 </DOCNO>
On the stability of cosmological metrics in Einstein-Cartan cosmologies


  Two metric perturbations in Einstein-Cartan cosmology are examined.The first
case is the scalar mode perturbation of de Sitter metric in Einstein-Cartan
cosmology.In this case small perturbations of de Sitter metric shows that this
metric is unstable for a universe with spin-torsion density and dilaton
fields.In the second case we show that the Friedmann metric in the same space
is also unstable under the small perturbations.

</DOC>
<DOC>
<DOCNO> 84573 </DOCNO>
Quantum Lightcone Fluctuations in Theories with Extra Dimensions


  The effects of small extra dimensions upon quantum fluctuations of the
lightcone are examined. We argue that compactified extra dimensions modify the
quantum fluctuations of gravitational field so as to induce lightcone
fluctuations. This phenomenon can be viewed as being related to the Casimir
effect. The observable manifestation of the lightcone fluctuations is
broadening of spectral lines from distant sources. In this paper, we further
develop the formalism used to describe the lightcone fluctuations, and then
perform explicit calculations for several models with flat extra dimensions. In
the case of one extra compactified dimension, we find a large effect which
places severe constraints on such models. When there is more than one
compactified dimension, the effect is much weaker and does not place a
meaningful constraint. We also discuss some brane worlds scenarios, in which
gravitons satisfy Dirichlet or Neumann boundary conditions on parallel
four-dimensional branes, separated by one or more flat extra dimensions.

</DOC>
<DOC>
<DOCNO> 121943 </DOCNO>
X-ray imaging of the Seyfert 2 galaxy Circinus with Chandra


  We present results from the zeroth-order imaging of a Chandra HETGS
observation of the nearby Seyfert 2 galaxy Circinus. Twelve X-ray sources were
detected in the ACIS-S image of the galaxy, embedded in diffuse X-ray emission.
The latter shows a prominent (~18arcsec) soft ``plume'' in the N-W direction,
coincident with the [OIII] ionization cone. The radial profiles of the
brightest X-ray source at various energies are consistent with an unresolved
(FWHM ~0.8arcsec) component, which we identify as the active nucleus, plus two
extended components with FWHMs ~ 2.3arcsec and 18arcsec, respectively. In a
radius of 3arcsec, the nucleus contributes roughly the same flux as the
extended components at the softest energies (< 2 keV). However, at harder
energies (> 2 keV), the contribution of the nucleus is dominant. The
zeroth-order ACIS spectrum of the nucleus exhibits emission lines at both soft
and hard X-rays, including a prominent Fe Kalpha line at 6.4 keV, showing that
most of the X-ray lines previously detected with ASCA originate in a compact
region (<15 pc). Based on its X-ray spectrum, we argue that the 2.3arcsec
extended component is scattered nuclear radiation from nearby ionized gas. The
large-scale extended component includes the emission from the N-W plume and
possibly from the outer starburst ring.

</DOC>
<DOC>
<DOCNO> 70433 </DOCNO>
The process \gamma \gamma -> \gamma \gamma, \gamma Z, ZZ


  The Standard Model contributions to the processes $\gamma \gamma \to \gamma
\gamma$, $\gamma Z$ and ZZ at sufficiently high energies, are found to be
helicity conserving and almost purely imaginary. This is due to the W-loop
contribution, which is much bigger than the fermionic ones at such energies.
Thus the structure of these amplitudes acquires an impressive simplicity at
high energies. Nothing like this appears in other process like e.g. the the
production of a pair of neutral Higgs bosons.

</DOC>
<DOC>
<DOCNO> 123115 </DOCNO>
ALMA and high redshift dusty starburst mergers


  By using a new numerical code for deriving the spectral energy distributions
of galaxies, we have investigated the time evolution of morphological
properties, the star formation rate, and the submillimeter flux at 850 $\mu$m
in high-redshift ($z$) dusty starburst mergers with mass ratio ($m_{2}$) of two
disks ranging from 0.1 (minor merger) to 1.0 (major one). We found that the
maximum star-formation rate, the degree of dust extinction, and the 850 $\mu$m
flux are larger for mergers with larger $m_{2}$. The 850 $\mu$m flux from
mergers at 1.5 $\le z \le$ 3.0 in the observer frame is found to be a few mJy
for major merger cases, and at most $\sim$ 100 $\mu$Jy for minor ones. This
result suggests that only high-redshift major mergers are now detected by SCUBA
with the current 850 $\mu m$ detection limit of a few mJy. These results imply
that LMSA (ALMA) with the expected detection limit of the order of 10 $\mu$Jy
at 850 $\mu m$ can be used to study high-redshift mergers with variously
different $m_2$, and thus provide an important clue to the formation of
galaxies in a high-redshift universe.

</DOC>
<DOC>
<DOCNO> 7760 </DOCNO>
Equilibrium and adhesion of Nb/sapphire: the effect of oxygen partial


  We derive a formula, useful for first-principles calculations, which relates
the free energy of an oxide/metal interface to the free energies of surfaces
and the work of separation of the interface. We distinguish the latter {\it
mechanical} quantity from the {\it thermodynamic} work of adhesion, and we
describe explicitly how both may be calculated. Our formulae for interfacial
and surface energies are cast in terms of quantities which can be calculated or
looked up in tables, and include as additional parameters the ambient
temperature and partial pressure of oxygen $P_{O_2}$. From total energy
calculations for the Nb(111)/alpha-alumina(0001) interface, free Nb and alumina
surfaces, we obtain firstly numerical estimates of the works of separation,
which are independent of $P_{O_2}$. We then obtain surface energies,
interfacial energies and the equilibrium work of adhesion as a function of
$P_{O_2}$.

</DOC>
<DOC>
<DOCNO> 11114 </DOCNO>
Multi-Player Quantum Games


  Recently the concept of quantum information has been introduced into game
theory. Here we present the first study of quantum games with more than two
players. We discover that such games can possess a new form of equilibrium
strategy, one which has no analogue either in traditional games or even in
two-player quantum games. In these `pure' coherent equilibria, entanglement
shared among multiple players enables new kinds of cooperative behavior: indeed
it can act as a contract, in the sense that it prevents players from
successfully betraying one-another.

</DOC>
<DOC>
<DOCNO> 122375 </DOCNO>
Slim Disk Model for Ultra-Luminous X-Ray Sources


  The Ultra Luminous X-ray Sources (ULXs) are unique in exhibiting moderately
bright X-ray luminosities, $L_{\rm x} \sim 10^{38-40} {\rm erg~s^{-1}}$, and
relatively high blackbody temperatures, $\Tin \sim 1.0-2.0 {\rm keV}$.
  From the constraint that $L_{\rm x}$ cannot exceed the Eddington luminosity,
$L_{\rm E}$, we require relatively high black-hole masses, $M\sim 10-100
M_\odot$, however, for such large masses the standard disk theory predicts
lower blackbody temperatures, $\Tin < 1.0$ keV. To understand a cause of this
puzzling fact, we carefully calculate the accretion flow structure shining at
$\sim L_{\rm E}$, fully taking into account the advective energy transport in
the optically thick regime and the transonic nature of the flow. Our
calculations show that at high accretion rate ($\dot M \ga 30~L_{\rm E}/c^2$)
an apparently compact region with a size of $\Rin \simeq (1-3)\rg$ (with $\rg$
being Schwarzschild radius) is shining with a blackbody temperature of $\Tin
\simeq 1.8 (M/10M_\odot)^{-1/4}$ keV even for the case of a non-rotating black
hole. Further, $\Rin$ decreases as $\dot M$ increases, on the contrary to the
canonical belief that the inner edge of the disk is fixed at the radius of the
marginally stable last circular orbit. Accordingly, the loci of a constant
black-hole mass on the "H-R diagram" (representing the relation between $L_{\rm
x}$ and $\Tin$ both on the logarithmic scales) are not straight but bent
towards the lower $M$ direction in the frame of the standard-disk relation.

</DOC>
<DOC>
<DOCNO> 8520 </DOCNO>
Carbon Nanotube Based Magnetic Tunnel Junctions


  Spin-coherent quantum transport in carbon nanotube magnetic tunnel junctions
was investigated theoretically. A spin-valve effect is found for metallic,
armchair tubes, with a magneto-conductance ratio ranging up to 20%. Because of
the finite length of the nanotube junctions, transport is dominated by resonant
transmission. The magnetic tunnel junctions are found to have distinctly
different transport behavior depending on whether or not the length of the
tubes is commensurate with a 3N+1 rule, with N the number of basic carbon
repeat units along the nanotube length.

</DOC>
<DOC>
<DOCNO> 101698 </DOCNO>
On the support of solutions to the g-KdV equation


  We discuss the question whether solutions of the initial value problem for
the generalized KdV equation can have compact support at two different times.

</DOC>
<DOC>
<DOCNO> 9116 </DOCNO>
Size and area of square lattice polygons


  We use the finite lattice method to calculate the radius of gyration, the
first and second area-weighted moments of self-avoiding polygons on the square
lattice. The series have been calculated for polygons up to perimeter 82.
Analysis of the series yields high accuracy estimates confirming theoretical
predictions for the value of the size exponent, $\nu=3/4$, and certain
universal amplitude combinations. Furthermore, a detailed analysis of the
asymptotic form of the series coefficients provide the firmest evidence to date
for the existence of a correction-to-scaling exponent, $\Delta = 3/2$.

</DOC>
<DOC>
<DOCNO> 84809 </DOCNO>
Symmetries of Bianchi I space-times


  All diagonal proper Bianchi I space-times are determined which admit certain
important symmetries. It is shown that for Homotheties, Conformal motions and
Kinematic Self-Similarities the resulting space-times are defined explicitly in
terms of a set of parameters whereas Affine Collineations, Ricci Collineations
and Curvature Collineations, if they are admitted, they determine the metric
modulo certain algebraic conditions. In all cases the symmetry vectors are
explicitly computed. The physical and the geometrical consequences of the
results are discussed and a new anisitropic fluid, physically valid solution
which admits a proper conformal Killing vector, is given.

</DOC>
<DOC>
<DOCNO> 72075 </DOCNO>
What if the Mass Difference $\Delta M_s$ is around 18 Inverse


  Present experiments in pursuit of the mass difference in the Bs-Bs(bar)
system have put a lower bound on this quantity of $\Delta M_s > 14.9 ps^{-1}$
(at 95% C.L.). The same experiments also yield a local minimum in the
log-likelihood function around $\Delta M_s = 17.7 ps^{-1}$, which is
$2.5\sigma$ away from being zero. Motivated by these observations, we
investigate the consequences of a possible measurement of $\Delta M_s = 17.7
\pm 1.4 ps^{-1}$, in the context of both the standard model and supersymmetric
models with minimal flavor violation. We perform a fit of the quark mixing
parameters in these theories and estimate the expected ranges of the CP
asymmetries in B decays, characterized by $\alpha$, $\beta$ and $\gamma$, the
interior angles of the CKM-unitarity triangle. Based on this study, we argue
that, if indeed $\Delta M_s$ turns out to be in its currently-favored range,
this would disfavor a large class of supersymmetric models. Indeed, of all the
models examined here, the best fit to the data occurs for the standard model.

</DOC>
<DOC>
<DOCNO> 70512 </DOCNO>
On Possibility of Higgs Mechanism Break Down Due to the Instantons


  Two-dimensional Abelian Higgs model is considered. It is shown that Higgs
mechanism of the gauge bosons masses generating is broken in presence of
instantons. It is supposed that discussion can be generalized into the standard
model of electroweak interactions.

</DOC>
<DOC>
<DOCNO> 12541 </DOCNO>
Localization on short-range potentials in dissipative quantum mechanics


  In this Letter the problem of the existence of a state localized on a weak
short-range attractive potential in the presence of dissipation is considered.
It is shown that, contrary to the pure quantum case, a localized state is
produced in any number of dimensions, while in low dimensions dissipation leads
to much stronger localization. The results have physical implications for the
dissipative dynamics of objects such as heavy particles in Fermi liquids and
for superconductivity in high-$T_c$ materials.

</DOC>
<DOC>
<DOCNO> 83457 </DOCNO>
Designing Proxies for Stock Market Indices is Computationally Hard


  In this paper, we study the problem of designing proxies (or portfolios) for
various stock market indices based on historical data. We use four different
methods for computing market indices, all of which are formulas used in actual
stock market analysis. For each index, we consider three criteria for designing
the proxy: the proxy must either track the market index, outperform the market
index, or perform within a margin of error of the index while maintaining a low
volatility. In eleven of the twelve cases (all combinations of four indices
with three criteria except the problem of sacrificing return for less
volatility using the price-relative index) we show that the problem is NP-hard,
and hence most likely intractable.

</DOC>
<DOC>
<DOCNO> 69749 </DOCNO>
Implications of a Rotating Mass Matrix


  The fermion mass matrix, in addition to having eigenvalues (masses) which
run, also changes its orientation (rotates) with changing energy scales. This
means that its eigenstates at one scale will no longer be eigenstates at
another scale, leading to effects where fermions of different flavours can
``transmute'' into one another. In this paper, the implications of a rotating
mass matrix are analysed and possible transmuation effects are investigated
both in the Standard Model (SM) and in the so-called Dualized Standard Model
(DSM) that we advocate, arriving at the conclusion that some transmutational
decays such as $\psi \longrightarrow \mu \tau$, $\Upsilon \longrightarrow \mu
\tau$ or $\pi^0 \longrightarrow e \mu$ may be within experimental range, if not
immediately, then in the near future.

</DOC>
<DOC>
<DOCNO> 13449 </DOCNO>
Comment on "Canonical and Mircocanonical Calculations for Fermi Systems"


  In the context of nuclear physics Pratt recently investigated noninteracting
Fermi systems described by the microcanonical and canonical ensemble. As will
be shown his discussion of the model of equally spaced levels contains a flaw
and a statement which is at least confusing.

</DOC>
<DOC>
<DOCNO> 68404 </DOCNO>
The Effects of Non-Local Interactions in Rare B Decays, B -> X_s l^+l^-


  The effects of non-local interactions in rare B decays, $\Bsll$, are
investigated. We show the correlation between the branching ratio and the
forward-backward asymmetry via two coefficients of the non-local interactions.
This will certainly help us find any deviations from the standard model through
the non-local interactions.

</DOC>
<DOC>
<DOCNO> 117772 </DOCNO>
LiBeB Evolution: Three Models


  We consider the three principal LiBeB evolutionary models, CRI in which the
cosmic-ray source at all epochs of Galactic evolution is the average ISM,
CRI+LECR in which metal enriched low energy cosmic rays (LECRs) are
superimposed onto the CRI cosmic rays, and CRS in which the cosmic-ray source,
accelerated in superbubbles, is constant, independent of the ISM metallicity.
By considering the evolutionary trend of log(Be/H) vs. both [Fe/H] and [O/H],
we demonstrate that the CRI model is energetically untenable. We present
evolutionary trends for B-11/B-10 and B/Be which, combined with future
precision measurements, could distinguish between the CRS and CRI+LECR models.
We show that delayed LiBeB synthesis in the CRS model, due to the transport of
the cosmic rays, could explain why log(Be/H) is steeper vs. [O/H] than vs.
[Fe/H]. We also show that delayed deposition of Fe into star forming regions,
due to its incorporation into high velocity dust, could provide an explanation
for the possible rise of [O/Fe] with decreasing [Fe/H]. Observations of
refractory and volatile alpha-elements could test this scenario. There seems to
be a need for pregalactic or extragalactic Li-6 sources.

</DOC>
<DOC>
<DOCNO> 68189 </DOCNO>
Axion Searches


  The strong CP problem and its resolution through the existence of an axion
are briefly reviewed. The constraints on the axion from accelerator searches,
from the evolution of red giants and from supernova SN1987a combine to require
$m_a < 3 \cdot 10^{-3}$ eV, where $m_a$ is the axion mass. On the other hand,
the constraint that axions do not overclose the universe implies $m_a \gtwid
10^{-6}$ eV. If $m_a \sim 10^{-5}$ eV, axions contribute significantly to the
cosmological energy density in the form of cold dark matter. Dark matter axions
can be detected by resonant conversion to microwave photons in a cavity
permeated by a static magnetic field and tuned to the axion mass. Experiments
using this effect are described, as well as several other types of axion
searches.

</DOC>
<DOC>
<DOCNO> 120076 </DOCNO>
Solar Oscillations and Convection: I. Formalism for Radial Oscillations


  We present a formalism for investigating the interaction between pmode
oscillations and convection by analyzing realistic, three-dimensional
simulations of the near-surface layers of the solar convection zone. By
choosing suitable definitions for fluctuations and averages, we obtain a
separation that retains exact equations. The equations for the horizontal
averages contain one part that corresponds directly to the wave equations for a
1-D medium, plus additional terms that arise from the averaging and correspond
to the turbulent pressure gradient in the momentum equation and the divergence
of the convective and kinetic energy fluxes in the internal energy equation.
These terms cannot be evaluated in closed form, but they may be measured in
numerical simulations. The additional terms may cause the mode frequencies to
shift, relative to what would be obtained if only the terms corresponding to a
1-D medium were retained---most straightforwardly by changing the mean
stratification, and more subtly by changing the effective compressibility of
the medium. In the presence of time dependent convection, the additional terms
also have a stochastic time dependence, that acts as a source of random
excitation of the coherent modes. In the present paper, we derive an expression
for the excitation power and test it by applying it to a numerical experiment
of sufficient duration for the excited modes to be spectrally resolved.

</DOC>
<DOC>
<DOCNO> 69030 </DOCNO>
The Cosmological Constant Problems (Talk given at Dark Matter 2000,


  The old cosmological constant problem is to understand why the vacuum energy
is so small; the new problem is to understand why it is comparable to the
present mass density. Several approaches to these problems are reviewed.
Quintessence does not help with either; anthropic considerations offer a
possibility of solving both. In theories with a scalar field that takes random
initial values, the anthropic principle may apply to the cosmological constant,
but probably to nothing else.

</DOC>
<DOC>
<DOCNO> 9131 </DOCNO>
High Field Mobility and Diffusivity of Electron Gas in Silicon Devices


  In this paper the Boltzmann equation describing the carrier transport in a
semiconductor is considered. A modified Chapman-Enskog method is used, in order
to find approximate solutions in the weakly non-homogeneous case. These
solutions allow to calculate the mobility and diffusion coefficients as
function of the electric field. The integral-differential equations derived by
the above method are numerically solved by means of a combination of spherical
harmonics functions and finite-difference operators. The Kane model for the
electron band structure is assumed; the parabolic band approximation is
obtained as a particular case. The numerical values for mobility and
diffusivity in a silicon device are compared with the experimental data. The
Einstein relation is also shown.

</DOC>
<DOC>
<DOCNO> 151019 </DOCNO>
Nonlocal Regularization For Non-Abelian Gauge Theories For Arbitrary


  We study the nonlocal regularization for the non-abelian gauge theories for
an arbitrary value of the gauge parameter (\xi). We show that the procedure for
the nonlocalization of field theories established earlier by the original
authors, when applied in that form to the Faddeev-Popov effective action in a
linear gauge cannot lead to a (\xi)-independent result for the observables. We
then show that an alternate procedure which is simpler can be used and that it
leads to the S-matrix elements (where they exist) independent of (\xi).

</DOC>
<DOC>
<DOCNO> 13461 </DOCNO>
Beyond the Gross-Pitaevskii Equation: Ground State and Low Energy


  The results of a modified Gross-Pitaevskii equation for a system of Bose hard
spheres trapped in a spherical harmonic potential are analyzed to study the
validity regime of the standard GP equation.

</DOC>
<DOC>
<DOCNO> 68299 </DOCNO>
Low-Scale Anomalous U(1) and Decoupling Solution to Supersymmetric


  Supersymmetric standard models where the ultraviolet cut-off scale is only a
few orders of magnitude higher than the electroweak scale are considered.
Phenomenological consequences of this class of models are expected to be very
different from, for example, the conventional supergravity scenario. We apply
this idea to a model with an anomalous U(1) gauge group and construct a viable
model in which some difficulties of the decoupling solution to the
supersymmetric flavor problem are ameliorated.

</DOC>
<DOC>
<DOCNO> 101272 </DOCNO>
Kashaev's invariant and the volume of a hyperbolic knot after Y. Yokota


  I follow Y. Yokota to explain how to obtain a tetrahedron decomposition of
the complement of a hyperbolic knot and compare it with the asymptotic behavior
of Kashaev's link invariant using the figure-eight knot as an example.

</DOC>
<DOC>
<DOCNO> 69132 </DOCNO>
The role of secondary Reggeons in central meson production


  We estimate the contribution of f_2 trajectory exchange to the central \eta
and \eta^\prime production. It is shown that secondary Reggeons may give a
large contribution to processes of double diffractive meson production at high
energy.

</DOC>
<DOC>
<DOCNO> 116525 </DOCNO>
Study of nucleating efficiency of superheated droplets by neutrons


  Superheated droplets are proven to be excelent detectors for neutrons and
could be used as a neutron dosimeter. To detect accurately the volume of the
vapour formed upon nucleation and hence to observe the nucleation
quantitatively an air displacement system has been developed.

</DOC>
<DOC>
<DOCNO> 11935 </DOCNO>
EQSE Diagonalization of the Hubbard Model


  The application of enhanced quasi-sparse eigenvector methods (EQSE) to the
Hubbard model is attempted. The ground state energy for the 4x4 Hubbard model
is calculated with a relatively small set of basis vectors. The results agree
to high precision with the exact answer. For the 8x8 case, exact answers are
not available but a simple first order correction to the quasi-sparse
eigenvector (QSE) result is presented.

</DOC>
<DOC>
<DOCNO> 101046 </DOCNO>
Nonclassical Lagrangian Dynamics and Potential Maps


  Section 1 refines the theory of harmonic and potential maps. Section 2
defines a generalized Lorentz world-force law and shows that any PDEs system of
order one generates such a law in suitable geometrical structure. In other
words, the solutions of any PDEs system of order one are harmonic or potential
maps, if we use semi-Riemann-Lagrange structures. Section 3 formulates open
problems regarding the geometry of semi-Riemann manifolds $(J^1(T,M), S_1)$,
$(J^2(T,M), S_2)$, and shows that the Lorentz-Udriste world-force law is
equivalent to covariant Hamilton PDEs on $(J^1(T,M), S_1)$.

</DOC>
<DOC>
<DOCNO> 116690 </DOCNO>
Optical Approach to Gravitational Redshift


  This paper explores an optical interpretation of the gravitational redshift
effect, and shows how the deflection of light and the radar echo delay can be
calculated from the point of view of optics. As a result of these
considerations, this work establishes new relationships between general
relativity and geometrical optics with regard to the propagation of light in
the gravitational field, introducing an optical metric - the optical version of
the Schwarzschild metric.

</DOC>
<DOC>
<DOCNO> 85602 </DOCNO>
Comparing quantum black holes and naked singularities


  There are models of gravitational collapse in classical general relativity
which admit the formation of naked singularities as well as black holes. These
include fluid models as well as models with scalar fields as matter. Even if
fluid models were to be regarded as unphysical in their matter content, the
remaining class of models (based on scalar fields) generically admit the
formation of visible regions of finite but arbitrarily high curvature. Hence it
is of interest to ask, from the point of view of astrophysics, as to what a
stellar collapse leading to a naked singularity (or to a visible region of very
high curvature) will look like, to a far away observer. The emission of energy
during such a process may be divided into three phases - (i) the classical
phase, during which matter and gravity can both be treated according to the
laws of classical physics, (ii) the semiclassical phase, when gravity is
treated classically but matter behaves as a quantum field, and (iii) the
quantum gravitational phase. In this review, we first give a summary of the
status of naked singularities in classical relativity, and then report some
recent results comparing the semiclassical phase of black holes with the
semiclassical phase of spherical collapse leading to a naked singularity. In
particular, we ask how the quantum particle creation during the collapse
leading to a naked singularity compares with the Hawking radiation from a star
collapsing to form a black hole. It turns out that there is a fundamental
difference between the two cases. A spherical naked star emits only about one
Planck energy during its semiclassical phase, and the further evolution can
only be determined by the laws of quantum gravity. This contrasts with the
semiclassical evaporation of a black hole.

</DOC>
<DOC>
<DOCNO> 13654 </DOCNO>
Consistent Anisotropic Repulsions for Simple Molecules


  We extract atom-atom potentials from the effective spherical potentials that
suc cessfully model Hugoniot experiments on molecular fluids, e.g., $O_2$ and
$N_2$. In the case of $O_2$ the resulting potentials compare very well with the
atom-atom potentials used in studies of solid-state propertie s, while for
$N_2$ they are considerably softer at short distances. Ground state (T=0K) and
room temperatu re calculations performed with the new $N-N$ potential resolve
the previous discrepancy between experimental and theoretical results.

</DOC>
<DOC>
<DOCNO> 170177 </DOCNO>
Scaling Considerations in Ground State Quantum Computation


  We study design challenges associated with realizing a ground state quantum
computer. In such a computer, the energy gap between the ground state and first
excited state must be sufficiently large to prevent disruptive excitations.
Here, an estimate is provided of this gap as a function of computer size. We
then address the problem of detecting the output of a ground state quantum
computer. It is shown that the exponential detection difficulties that appear
to be present at first can be overcome in a straightforward manner by small
design changes.

</DOC>
<DOC>
<DOCNO> 8066 </DOCNO>
Self-Similar Crossover in Statistical Physics


  An analytical method is advanced for constructing interpolation formulae for
complicated problems of statistical mechanics, in which just a few terms of
asymptotic expansions are available. The method is based on the self-similar
approximation theory, being its variant where control functions are defined
from asymptotic crossover conditions. Several examples from statistical physics
demonstrate that the suggested method results in rather simple and surprisingly
accurate formulae.

</DOC>
<DOC>
<DOCNO> 121575 </DOCNO>
Aberration of Light and Motion of Real Particle


  Correct and complete (to terms of $\vec{v} / c$ -- $\vec{v}$ is particle's
velocity, $c$ is the speed of light) derivation of equation of motion for real
dust particle under the action of electromagnetic radiation is derived. The
effect of aberration of light is used. Equation of motion is expressed in terms
of particle's optical properties, standardly used in optics for stationary
particles.

</DOC>
<DOC>
<DOCNO> 151396 </DOCNO>
BRST invariant $CP^{1}$ model through improved Dirac quantization


  The Batalin-Fradkin-Tyutin (BFT) scheme, which is an improved version of
Dirac quantization, is applied to the $CP^1$ model, and the compact form of a
nontrivial first-class Hamiltonian is directly obtained by introducing the BFT
physical fields. We also derive a BRST-invariant gauge fixed Lagrangian through
the standard path-integral procedure. Furthermore, performing collective
coordinate quantization we obtain energy spectrum of rigid rotator in the
$CP^1$ model. Exploiting the Hopf bundle, we also show that the $CP^1$ model is
exactly equivalent to the O(3) nonlinear sigma model at the canonical level.

</DOC>
<DOC>
<DOCNO> 13195 </DOCNO>
Free Random Levy Matrices


  Using the theory of free random variables (FRV) and the Coulomb gas analogy,
we construct stable random matrix ensembles that are random matrix
generalizations of the classical one-dimensional stable L\'{e}vy distributions.
We show that the resolvents for the corresponding matrices obey transcendental
equations in the large size limit. We solve these equations in a number of
cases, and show that the eigenvalue distributions exhibit L\'{e}vy tails. For
the analytically known L\'{e}vy measures we explicitly construct the density of
states using the method of orthogonal polynomials. We show that the L\'{e}vy
tail-distributions are characterized by a novel form of microscopic
universality.

</DOC>
<DOC>
<DOCNO> 119713 </DOCNO>
Cluster Correlation in Mixed Models


  We evaluate the dependence of the cluster correlation length r_c on the mean
intercluster separation D_c, for three models with critical matter density,
vanishing vacuum energy (Lambda = 0) and COBE normalized: a tilted CDM (tCDM)
model (n=0.8) and two blue mixed models with two light massive neutrinos
yielding Omega_h = 0.26 and 0.14 (MDM1 and MDM2, respectively). All models
approach the observational value of sigma_8 (and, henceforth, the observed
cluster abundance) and are consistent with the observed abundance of Damped
Lyman_alpha systems. Mixed models have a motivation in recent results of
neutrino physics; they also agree with the observed value of the ratio
sigma_8/sigma_25, yielding the spectral slope parameter Gamma, and nicely fit
LCRS reconstructed spectra. We use parallel AP3M simulations, performed in a
wide box (side 360/h Mpc) and with high mass and distance resolution, enabling
us to build artificial samples of clusters, whose total number and mass range
allow to cover the same D_c interval inspected through APM and Abell cluster
clustering data. We find that the tCDM model performs substantially better than
n=1 critical density CDM models. Our main finding, however, is that mixed
models provide a surprisingly good fit of cluster clustering data.

</DOC>
<DOC>
<DOCNO> 178549 </DOCNO>
Calculation of Exclusive Cross Sections with the Lorentz Integral


  The longitudinal structure function of the d(e,e'p) exclusive cross section
is calculated with the Lorentz integral transform method. In this approach
final state interaction is fully taken into account, but without using a final
state wave function. Cross sections are obtained via the inversion of the
transform. It is shown that the inversion results are very stable. The
comparison to a conventional calculation with an explicit np final state wave
function shows that the obtained results are also very precise. Thus the method
opens up the possibility to obtain exclusive cross sections for reactions with
more than two particles, where it is generally very difficult to calculate the
exact final state wave function.

</DOC>
<DOC>
<DOCNO> 117826 </DOCNO>
Superwind model of extended Lyman alpha emitters at high redshift


  We propose a new model for the extended Ly alpha blobs found recently at high
redshift z ~ 3. The observational properties of these blobs are; 1) the
observed Ly alpha luminosities are ~ 10^{43} h^{-2} ergs s^{-1}, 2) they appear
elongated morphologically, 3) their sizes amount to ~ 100 kpc, 4) the observed
line widths amount to ~ 1000 km s^{-1}, and 5) they are not associated with
strong radio-continuum sources. All these observational properties seem to be
explained in terms of galactic winds driven by successive supernova explosions
shortly after the initial burst of massive star formation in the galactic
centers. The observed number density of Ly alpha blobs (~ 3.4 x 10^{-5} h^3
Mpc^{-3}) may be explained if their present-day counterparts are elliptical
galaxies with a luminosity above ~ 1 L^*.

</DOC>
<DOC>
<DOCNO> 67991 </DOCNO>
Electron - Proton Scattering as a Probe of Nucleon Structure


  The problem of electron-proton scattering is handed over both the elastic and
inelastic scattering. Two models are presented in this sense. The first,
depends on the multi photon exchange ladder diagram, where the transition
matrix is expanded in multi steps form. The second model uses the multi
peripheral mechanism developed for the electromagnetic field. It allows the
particle production in the inelastic scattering processes. An iterative
procedure is found and inserted in a Monte Carlo program to reproduce the
differential cross section of the reaction. The comparison with the
experimental data shows bid fair in most cases.

</DOC>
<DOC>
<DOCNO> 170486 </DOCNO>
Zero knowledge convincing protocol on quantum bit is impossible


  Consider two parties: Alice and Bob and suppose that Bob is given a qubit
system in a quantum state $\phi$, unknown to him. Alice knows $\phi$ and she is
supposed to convince Bob that she knows $\phi$ sending some test message. Is it
possible for her to convince Bob providing him "zero knowledge" i. e. no
information about $\phi$ he has? We prove that there is no "zero knowledge"
protocol of that kind. In fact it turns out that basing on Alice message, Bob
(or third party - Eve - who can intercept the message) can synthetize a copy of
the unknown qubit state $\phi$ with nonzero probability. This "no-go" result
puts general constrains on information processing where information {\it about}
quantum state is involved.

</DOC>
<DOC>
<DOCNO> 121740 </DOCNO>
The Shape and Orientation of NGC 3379: Implications for Nuclear


  The intrinsic shape and orientation of the elliptical galaxy NGC 3379 are
estimated by dynamical modeling. The maximal ignorance shape estimate, an
average over the parameter space, is axisymmetric and oblate in the inner
parts, with an outward triaxiality gradient. The 1 sigma limits on total-mass
triaxiality T are T < 0.13 at 0.33 kpc and T = 0.08 +/- 0.07 at 3.5 kpc from
the center. The luminous short-to-long axis ratio c_L = 0.79 +0.05-0.1 inside
0.82 kpc, flattening to c_L = 0.66 +0.07-0.08 at 1.9 kpc. The results are
similar if the galaxy is assumed to rotate about its short axis. Estimates for
c_L are robust, but those for T are dependent on whether the internal rotation
field is disklike or spheroid-like. Short-axis inclinations between 30 and 50
degrees are preferred for nearly axisymmetric models; but triaxial models in
high inclination are also allowed, which can affect central black hole mass
estimates. The available constraints on orientation rule out the possibility
that the nuclear dust ring at R = 1.5" is in a stable equilibrium in one of the
galaxy's principal planes. The ring is thus a decoupled nuclear component not
linked to the main body of the galaxy. It may be connected with ionized gas
that extends to larger radii, since the projected gas rotation axis is near the
minor axis of the ring. The gas and dust may both be part of a strongly warped
disk; however, if caused by differential precession, the warp will wind up on
itself in a few 10^7 years. The decoupling with the stellar component suggests
that the gas has an external origin, but no obvious source is present.

</DOC>
<DOC>
<DOCNO> 40341 </DOCNO>
Comparison of Deep Inelastic Electron-Photon Scattering Data with the


  Deep inelastic electron-photon scattering is studied in the Q**2 range from
1.2 to 30 GeV**2 using the LEP1 data taken with the ALEPH, L3 and OPAL
detectors at centre-of-mass energies close to the mass of the Z boson.
Distributions of the measured hadronic final state are corrected to the hadron
level and compared to the predictions of the HERWIG and PHOJET Monte Carlo
models. For large regions in most of the distributions studied the results of
the different experiments agree with one another. However, significant
differences are found between the data and the models. Therefore the combined
LEP data serve as an important input to improve on the Monte Carlo models.

</DOC>
<DOC>
<DOCNO> 119235 </DOCNO>
28SiO, 29SiO and 30SiO excitation: effects of infrared line overlaps


  We have investigated the influence of several line overlaps between 28SiO,
29SiO and 30SiO on maser emission from the envelopes of late-type stars using
the Large Velocity Gradient radiative transfer formalism modified to account
for overlaps. Our model includes: (i) 40 rotational levels for each of the v=0
to 4 vibrational states and each isotopic species; (ii) collisions with
molecular and atomic hydrogen; and (iii) radiative pumping by a shell of dust
grains surrounding the SiO masing layers.
  We have shown that several line overlaps may play a role on the excitation of
the 28SiO v=3, J=1-0 maser, and on the anomalously weak v=3, J=2-1 emission. We
suggest that 28SiO maser emission in the v=4, J=5-4 line, the only one observed
in this vibrational level, may also result from line overlaps. For 29SiO,
infrared line overlaps successfully explain observed maser emission in the v=0,
J=5-4 and v=1, 2, J=6-5 lines. 30SiO, v=0, J=2-1, and v=0, J=4-3 maser
emissions could also result from line overlaps, and we find that several
overlaps could explain the newly discovered maser line 30SiO v=1, J=1-0.
Finally, we make some predictions for new 28SiO, 29SiO and 30SiO maser lines.

</DOC>
<DOC>
<DOCNO> 118743 </DOCNO>
Cut-off radii of galactic disks: A statistical study on the truncation


  We present the analysis of a CCD survey of 31 nearby (<= 110 Mpc) edge-on
spiral galaxies. The three-dimensional one-component best fit models provide
their disk-scalelengths h and for the first time their disk cut-off radii
R_{co}. We confirm for this sample the existence of such sharp truncations, and
find a significantly lower mean value of the distance independent ratio
R_{co}/h =2.9 +- 0.7 than the standard value of 4.5 often used in the
literature. Our data show no correlation of these parameters with Hubble type,
whereas we report a correlation between R_{co}/h and the distance based
scalelength in linear units. Compared to the Milky Way we find only lower
values of R_{co}/h, explained either by possible selection effects or by the
completely different techniques used. We discuss our data in respect to present
models for the origin of the cut-off radii, either as a relict of the galaxy
formation process, or as an evolutionary phenomenon.

</DOC>
<DOC>
<DOCNO> 69200 </DOCNO>
Solving the Hierarchy Problem in Two-Brane Cosmological Models


  We analyze cosmological solutions in the class of two-brane models with
arbitrary tensions which contain matter with general equations of state. We
show that the mass hierarchy between the two branes is determined by the ratio
of the lapse functions evaluated on the branes. This ratio can be sufficiently
small without fine-tuning the brane separation, once the transverse dimension
is stabilized. For suitably large interbrane separations, both brane tensions
are positive. We also find that the cosmological evolution obeys the standard
four-dimensional Friedman equation up to small corrections.

</DOC>
<DOC>
<DOCNO> 121754 </DOCNO>
A Hard Tail in the Broad Band Spectrum of the Dipper XB 1254-690


  We report on the results of spectral analysis of the dipping source XB
1254-690 observed by the BeppoSAX satellite. We find that the X-ray dips are
not present during the BeppoSAX observation, in line with recent RXTE results.
The broad band (0.1-100 keV) energy spectrum is well fitted by a
three-component model consisting of a multicolor disk blackbody with an inner
disk temperature of ~0.85 keV, a comptonized spectrum with an electron
temperature of ~2 keV, and a bremsstrahlung at a temperature of ~20 keV.
Adopting a distance of 10 kpc and taking into account a spectral hardening
factor of ~1.7 (because of electron scattering which modifies the blackbody
spectrum emitted by the disk) we estimated that the inner disk radius is
$R_{\rm in} \sqrt{\cos i} \sim 11$ km, where i is the inclination angle of the
system with respect to the line of sight. The comptonized component could
originate in a spherical corona or boundary layer, surrounding the neutron
star, with optical depth ~19. The bremsstrahlung emission, contributing ~4% of
the total luminosity, probably originates in an extended accretion disk corona
with radius $\sim 10^{10}$ cm. In this scenario we calculated that the optical
depth of this region is ~0.71 and its mean electron density is $N_e \sim 2.7
\times 10^{14}$ cm$^{-3}$. This last component might also be present in other
low mass X-ray binaries, but, because of its low intrinsic luminosity, it is
not easily observable. We also find an absorption edge at ~1.27 keV with an
optical depth of ~0.15. Its energy could correspond to the L-edge of Fe XVII,
or K-edge of Ne X or neutral Mg.

</DOC>
<DOC>
<DOCNO> 71803 </DOCNO>
On the Dual Standard Model's Structure and some Related Toy models


  Withdrawn; note hep-th/0110236 covers some similar material.

</DOC>
<DOC>
<DOCNO> 151833 </DOCNO>
Normalization of the Background Independent Open String Field Theory


  It has been shown recently that the background independent open string field
theory provides an exact description of the tachyon condensation on unstable
D-branes of bosonic string theory. In this analysis the overall normalisation
of the action was chosen so that it reproduces the conjectured relations
involving tachyon condensation. In this paper we fix this normalisation by
comparing the on-shell three tachyon amplitude computed from the background
independent open string field theory with the same amplitude computed from the
cubic open string field theory, which in turn agrees with the result of the
first quantised theory. We find that this normalisation factor is in precise
agreement with the one required for verifying the conjectured properties of the
tachyon potential.

</DOC>
<DOC>
<DOCNO> 68386 </DOCNO>
What are sterile neutrinos good for?


  Taken at face value, current experimental data indicate the existence of a
new particle, the sterile neutrino, which must be a singlet under the Standard
Model gauge group. Although they are not detectable through traditional means,
such particles have interesting observable consequences for particle
astrophysics and cosmology. Here we examine these implications and discuss, in
particular, sterile neutrino dark matter and the relationship between
matter-enhanced active-sterile neutrino transformation and the synthesis of
heavy elements in supernovae.

</DOC>
<DOC>
<DOCNO> 169716 </DOCNO>
Dynamical Generation of Noiseless Quantum Subsystems


  We present control schemes for open quantum systems that combine decoupling
and universal control methods with coding procedures. By exploiting a general
algebraic approach, we show how appropriate encodings of quantum states result
in obtaining universal control over dynamically-generated noise-protected
subsystems with limited control resources. In particular, we provide an
efficient scheme for performing universal encoded quantum computation in a wide
class of systems subjected to linear non-Markovian quantum noise and supporting
Heisenberg-type internal Hamiltonians.

</DOC>
<DOC>
<DOCNO> 170114 </DOCNO>
Single-Pulse Preparation of the Uniform Superpositional State used in


  We examine a single-pulse preparation of the uniform superpositional wave
function, which includes all basis states, in a spin quantum computer. The
effective energy spectrum and the errors generated by this pulse are studied in
detail. We show that, in spite of the finite width of the energy spectrum
bands, amplitude and phase errors can be made reasonably small.

</DOC>
<DOC>
<DOCNO> 72144 </DOCNO>
Rare decays $B\to X_s\tau^+\tau^-$ and $B_s\to \tau^+\tau^-\gamma$ in


  We examine the rare decays $B\to X_s\tau^+\tau^-$ and $B_s\to\tau^+\tau^-
\gamma$ in the framework of technicolor with scalars. The contributions from
both the neutral and charged scalars predicted in this model are evaluated. We
find that the branching ratios could be enhanced over the standard model
predictions by a couple of orders of magnitude in some part of parameter space.
The forward-backward asymmetry and the distributions of differential branching
ratios are also found to differ significantly from the standard model results.
Such large new physics effects might be observable in the new generation of B
experiments.

</DOC>
<DOC>
<DOCNO> 9193 </DOCNO>
The same superconducting criticality for underdoped and overdoped


  By measuring the superconducting diamagnetic moments for an underdoped and an
overdoped La_{2-x}Sr_xCuO_4 single crystal with equal qualities and roughly
equal transition temperatures, it is found that the underdoped sample has only
one transition which corresponds to H_{c2}, but the overdoped sample has two
transitions with the higher one at H_{c2}. Further investigation reveals the
same upper-critical field H_{c2} for both samples although the overall charge
densities are very different, indicating the possibility of a very direct and
detailed equivalence of the superconducting condensation process in the two
doping limits. The second transition for the overdoped sample can be understood
as the bulk coupling between the superconducting clusters produced by
macroscopic phase separation.

</DOC>
<DOC>
<DOCNO> 118996 </DOCNO>
Non-LTE Abundances and Consequences for the Evolution of the alpha


  Abundances of alpha-elements such as Ca and Mg in disk and halo stars are
usually derived from equivalent widths lines measured on high resolution
spectra, and assuming Local Thermodynamic Equilibrium (LTE) . In this paper, we
present non-LTE differential abundances derived by computing the statistical
equilibrium of CaI and MgI atoms, using high resolution equivalent widths
available in the literature for 252 dwarf to subgiant stars. These non-LTE
abundances combined with recent determination of non-LTE abundances of iron,
seem to remove the dispersion of the [Ca/Fe] and [Mg/Fe] ratios in the galactic
halo and disk phases, revealing new and surprising structures. These results
have important consequences for chemical evolution models of the Galaxy. In
addition, non-LTE abundance ratios for stars belonging to the M92 cluster
apparently have the same behavior. More high resolution observations, mainly of
globular clusters, are urgently needed to confirm our results.

</DOC>
<DOC>
<DOCNO> 121644 </DOCNO>
Charge Conjugation Violation in Supernovae and The Neutron Shortage for


  Core collapse supernovae are dominated by energy transport from neutrinos.
Therefore, some supernova properties could depend on symetries and features of
the standard model weak interactions. The cross section for neutrino capture is
larger than that for antineutrino capture by one term of order the neutrino
energy over the nucleon mass. This reduces the ratio of neutrons to protons in
the $\nu$-driven wind above a protoneutron star by approximately 20 % and may
significantly hinder r-process nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 11789 </DOCNO>
Hole distribution for (Sr,Ca,Y,La)_14 Cu_24 O_41 ladder compounds


  The unoccupied electronic structure for the Sr_14Cu_24O_41 family of two-leg
ladder compounds was investigated for different partial substitutions of Sr^2+
by Ca^2+, leaving the nominal hole count constant, and by Y^3+ or La^3+,
reducing the nominal hole count from its full value of 6 per formula unit.
Using polarization-dependent x-ray absorption spectroscopy on single crystals,
hole states on both the chain and ladder sites could be studied. While for
intermediate hole counts all holes reside on O sites of the chains, a partial
hole occupation on the ladder sites in orbitals oriented along the legs is
observed for the fully doped compound Sr_14Cu_24O_41. On substitution of Ca for
Sr orbitals within the ladder planes but perpendicular to the legs receive some
hole occupation as well.

</DOC>
<DOC>
<DOCNO> 13353 </DOCNO>
Recovery of the Fermi-liquid state in U_3Ni_3Sn_4 by pressure


  Measurements of the resistivity of single-crystalline U_3Ni_3Sn_4 under
hydrostatic pressure up to 1.8 GPa are reported. We show that the temperature
T_FL, below which the resistivity obeys the Fermi-liquid expression rho ~ T^2,
increases with pressure as T_FL ~ (p-p_c)^1/2. The analysis of the data within
the magnetotransport theory of Rosch lends strong support for an
antiferromagnetic quantum critical point in U_3Ni_3Sn_4 at a negative critical
pressure p_c of -0.04+-0.02 GPa. The proximity to an antiferromagnetic
instability in U_3Ni_3Sn_4 is consistent with the previously reported non-Fermi
liquid term in the low-temperature specific heat.

</DOC>
<DOC>
<DOCNO> 67844 </DOCNO>
Derivation of O(q^4) Effective Lagrangian in the Presence of External


  This is a progress report on the extension of the analysis of hep-ph/9909498
to constructing a complete list of O(q^4) terms in the presence of external
fields, directly within Heavy Baryon Chiral Perturbation Theory (HBChPT) {\it
without having to first construct the relativistic BChPT Lagrangian and then
carry out the ${1\over\rm m}$-reduction}. In addition to a phase rule to
implement all symmetries including charge conjugation invariance directly at
the nonrelativistic level, generalized Jacobi identities, curvature relation
(that relates the commutator of two covariant derivatives to a linear
combination of the traceless and isosinglet field strengths and the commutator
of two axial vector building blocks), Schouten's identity and the relationship
between the antisymmetrized covariant derivative - axial-(building block)
vector commutator and another traceless field strength, are used to ensure
linear independence of the terms and their low energy coupling constants. We
first construct O($q^4$) terms for off-shell nucleons, and then perform the
on-shell reduction, again within HBChPT.

</DOC>
<DOC>
<DOCNO> 8478 </DOCNO>
Critical behavior of n-vector model with quenched randomness


  We consider the Ginzburg-Landau phase transition model with O(n) symmetry
(i.e., the n-vector model) which includes a quenched randomness, i.e., a random
temperature disorder. We have proven rigorously that within the diagrammatic
perturbation theory the quenched randomness does not change the critical
exponents at n tending to 0, which is in contrast to the conventional point of
view based on the perturbative renormalization group theory.

</DOC>
<DOC>
<DOCNO> 11796 </DOCNO>
Magnetotransport measurements on freely suspended two-dimensional


  We present magnetotransport measurements on freely suspended two-dimensional
electron gases from AlGaAs/GaAs heterostructures. The technique to realize such
devices relies on a specially MBE grown GaAs/AlGaAs-heterostructure including a
sacrificial layer. We fabricated simple Hall-bars as well as quantum cavities
and quantum dot systems. We find well-pronounced Shubnikov-de Haas oscillations
and observe commensurability resonances, allowing characterization of the
electron gas in these 100 nm thin membranes.

</DOC>
<DOC>
<DOCNO> 101463 </DOCNO>
Extensions of Quasidiagonal C*-algebras and K-theory


  We study the extension problem for quasidiagonal (QD) C*-algebras (i.e. when
is an extension of QD C*-algebras again QD?). The main positive result states
that in many instances an extension will remain QD provided that a certain
boundary arising from the K-theory of the extension vanishes. A K-theoretic
Hahn-Banach type property is also introduced for QD C*-algebras. We show that
every nuclear QD C*-algebra has this Hahn-Banach property if and only if the
extension problem for many QD C*-algebras is completely determined by a
boundary map on K-theory.

</DOC>
<DOC>
<DOCNO> 14103 </DOCNO>
Optical response in one dimensional Mott Insulators


  We study the optical response of a Mott Hubbard system in the framework of
the half--filled Extended Hubbard Model using the Density Matrix
Renormalization Group (DMRG) method. We discuss the appearance of excitonic
features inside the spectral gap as the system goes from the Spin Density Wave
(SDW) to the Charge Density Wave (CDW) phase.

</DOC>
<DOC>
<DOCNO> 152579 </DOCNO>
Vector Supersymmetry and Finite Quantum Correction of Chern-Simons


  Vector supersymmetry is shown to exist also in light-cone gauge Chern-Simons
theory. Using a gauge invariant regularization scheme, we demonstrate
explicitly that the finite quantum correction to the coupling constant of
Chern-Simons theory is intimately associated with the breaking of vector
supersymmetry at the regularization level. The advantage of investigating such
a quantum phenomenon in the light-cone gauge is emphasized and the BRST and
vector supersymmetry invariance of quantum effective action is discussed.

</DOC>
<DOC>
<DOCNO> 120058 </DOCNO>
Halo Dark Matter and Ultra-High Energy Cosmic Rays


  The decay of very heavy metastable relics of the Early Universe can produce
ultra-high energy cosmic rays (UHECRs) in the halo of our own Galaxy. On
distance scales of the order of the halo size, energy losses are
negligible---no Greisen-Zatsepin-Kuzmin cutoff is expected. In this letter we
show that, as a consequence of the hierarchical build up of the halo, this
scenario predicts the existence of small scale anisotropies in the arrival
directions of UHECRs. We also suggest some consequences of this scenario which
will be testable with upcoming experiments, as Auger.

</DOC>
<DOC>
<DOCNO> 10888 </DOCNO>
Trions in a periodic potential


  The group-theoretical classification of trion states is presented. It is
based on considerations of products of irreducible representations of the 2D
translation group. For a given BvK period N degeneracy of obtained states is
N^2. Trions consist of two identical particles so the symmetrization of states
with respect to particles transposition is considered. Completely antisymmetric
states can be constructed by introducing antisymmetric spin functions. Two
symmetry adapted bases are considered. The third possibility is postponed for
the further investigations.

</DOC>
<DOC>
<DOCNO> 13837 </DOCNO>
Nonequilibrium Critical Dynamics of the 2D XY model


  The nonequilibrium critical dynamics of the 2D XY model is investigated
numerically through Monte Carlo simulations and analytically in the spin-wave
approximation. We focus in particular on the behaviour of the two-time response
and correlation functions and show that the ageing dynamics depends on the
initial conditions. The presence of critical fluctuations leads to non-trivial
violations of the fluctuation-dissipation theorem apparently reminiscent of the
three dimensional Edwards-Anderson spin glass model. We compute for this reason
the finite-size overlap probability distribution function and find that it is
related to the finite-time fluctuation-dissipation ratio obtained in the out of
equilibrium dynamics, provided that the temperature is not very low.

</DOC>
<DOC>
<DOCNO> 150527 </DOCNO>
Constructing the light-front QCD Hamiltonian


  We propose the light-front Lagrangian and the corresponding Hamiltonian that
produce a theory perturbatively equivalent to the conventional QCD in the
Lorentz coordinates after the regularization is removed. The regularization
used is nonstandard and breaks the gauge invariance. But after the
regularization is removed, this invariance is restored by the introduction of a
finite number of counterterms with coefficients dependent on the regularization
parameters.

</DOC>
<DOC>
<DOCNO> 119874 </DOCNO>
A combined analysis of cluster mass estimates from strong lensing, X-ray


  (Abridged)We present a combined analysis of mass estimates in the central
cores of galaxy clusters from the strong lensing, the X-ray measurements and
the universal density profile (NFW). Special attention is paid to the questions
(1)whether the previously claimed mass discrepancy between the strong lensing
and X-ray measurements is associated with the presence of cooling/non-cooling
flows, (2)whether the cusped NFW density model can provide a consistent cluster
mass with the strong lensing result and (3)whether a non-zero cosmological
constant can be of any help to reducing the strong lensing - X-ray mass ratios.
We analyse a sample of 26 arc-like images among 21 clusters. The X-ray and NFW
cluster masses are obtained by assuming that the intracluster gas is isothermal
and in hydrostatic equilibrium with the underlying gravitational potential of
the clusters. A statistical comparison of these three mass estimates reveals
that the mass discrepancies for all the events are well within a factor of 2.
We confirm the result of Allen that the larger mass discrepancy is only
detected in the intermediate cooling, especially non-cooling flow clusters,
thus attributing the mass discrepancy to the local dynamical activities in the
central regions. We show that the NFW profile yields a consistent cluster mass
with the conventional X-ray measurement, and any difference between these two
models must occur at even smaller radii (e.g. within the arc-like images) or at
large radii. Finally, a non-zero cosmological constant is able to moderately
reduce the mass ratios of m_lens to m_xray.

</DOC>
<DOC>
<DOCNO> 13080 </DOCNO>
Loop algorithm for Heisenberg models with biquadratic interaction and


  We present a new algorithm for quantum Monte Carlo simulation based on global
updating with loops. While various theoretical predictions are confirmed in one
dimension, we find, for S=1 systems on a square lattice with an
antiferromagnetic biquadratic interaction, that the intermediate phase between
the antiferromagnetic and the ferromagnetic phases is disordered and that the
two phase transitions are both of the first order in contrast to the
one-dimensional case. It is strongly suggested that the transition points
coincide those at which the algorithm changes qualitatively.

</DOC>
<DOC>
<DOCNO> 99505 </DOCNO>
Crystallographic Orbifolds: Towards a Classification of Unitary


  We study the moduli space C^2 of unitary two-dimensional conformal field
theories with central charge c=2. We construct all the 28 nonexceptional
nonisolated irreducible components of C^2 that may be obtained by an orbifold
procedure from toroidal theories. The parameter spaces and partition functions
are calculated explicitly, and all multicritical points and lines are
determined. We show that all but four of the 28 irreducible components of C^2
corresponding to nonexceptional orbifolds are directly or indirectly connected
to the moduli space of toroidal theories in C^2. We relate our results to those
by Dixon, Ginsparg, Harvey on the classification of c=3/2 superconformal field
theories and thereby give geometric interpretations to all nonisolated
orbifolds discussed there.

</DOC>
<DOC>
<DOCNO> 10544 </DOCNO>
The Jahn-Teller theorem for the 3d magnetic ions


  We argue that the Jahn-Teller theorem, if applied to 3d-ion compounds, has to
be considered in the orbital+spin space. It is despite of the weakness of the
intraatomic spin-orbit coupling.

</DOC>
<DOC>
<DOCNO> 151542 </DOCNO>
On HyperKahler Singularities


  Using a geometric realization of the $SU(2)_R$ symmetry and a procedure of
factorisation of the gauge and $SU(2)_R$ charges, we study the small instanton
singularities of the Higgs branch of supersymmetric $U(1)^r$ gauge theories
with eight supercharges. We derive new solutions for the moduli space of vacua
preserving manifestly the eight supercharges. In particular, we obtain an
extension of the ordinary ADE singularities for hyperKahler manifolds and show
that the classical moduli space of vacua is in general given by cotangent
bundles of compact weighted projective spaces.

</DOC>
<DOC>
<DOCNO> 174476 </DOCNO>
Dynamics of Multifragmentation in Heavy Ion Collisions


  We review multifragmentation data obtained at the SIS/GSI accelerator using
heavy ion beams with (0.1-1)A GeV together with the ALADIN and FOPI
experimental setups.

</DOC>
<DOC>
<DOCNO> 122832 </DOCNO>
Sunyaev-Zel'dovich distortion from early galactic winds


  We consider the distortion in the cosmic microwave background (CMB) due to
galactic winds at high redshift. Winds outflowing from galaxies have been
hypothesized to be possible sources of metals in the intergalactic medium,
which is known to have been enriched to $10^{-2.5}$ Z$_{\odot}$ at $z \sim 3$.
We model these winds as functions of mass of the parent galaxy and redshift,
assuming they activate at a common initial redshift, $z_{in}$, and calculate
the mean $y$ distortion and the angular power spectrum of the distortion in the
CMB. We find that the thermal Sunyaev-Zel'dovich (SZ) effect due to the winds
to be consistent with previous estimates. The distortion due to the kinetic SZ
(kSZ) effect is, however, found to be more important than the thermal SZ (tSZ)
effect. We find that the distortion due to galactic winds is an important
contribution to the power spectrum of distortion at very small angular scales
$(l \sim 10^4)$. We also find that the power spectrum due to clustering
dominates the Poisson power spectrum for $l \le 4\hbox{--}5 \times 10^5$. We
show explicitly how the combined power spectrum from wind dominates over that
of clusters at 217 GHz, relevant for PLANCK. We also show how these constraints
change when the efficiency of the winds is varied.

</DOC>
<DOC>
<DOCNO> 117215 </DOCNO>
Application of time-dependent density functional theory to


  Optical properties of symmetry-forbidden pi-pi transitions in benzene are
calculated with the time-dependent density functional theory (TDDFT), using an
adiabatic LDA functional. Quantities calculated are the envelopes of the
Franck-Condon factors of the vibrationally promoted transitions and the
associated oscillator strengths. The strengths, which span three orders of
magnitude, are reproduced to better than a factor of two by the theory.
Comparable agreement is found for the Franck-Condon widths. We conclude that
rather detailed information can be obtained with the TDDFT and it may be
worthwhile to explore other density functionals.

</DOC>
<DOC>
<DOCNO> 39853 </DOCNO>
Are Messages of R-parity Violating Supersymmetry Hidden within Top Quark


  In an R-parity nonconserving supersymmetric theory, the lighter stop can
dominantly decay into $b\mu$ and $b\tau$ if R-parity breaking has to explain
the neutrino mass and mixing pattern suggested by the data on atmospheric muon
neutrinos. This should give rise to $dilepton+dijet$ and $single-lepton+jets$,
signals resembling those of the top quark at the Fermilab Tevatron. One can
thus constrain the stop parameter space using the current top search data, and
similarly look for the first signals of supersymmetry at the upgraded runs of
the Tevatron.

</DOC>
<DOC>
<DOCNO> 68088 </DOCNO>
Non-Abelian Flat Directions in a Minimal Superstring Standard Model


  Recently, by studying exact flat directions of non-Abelian singlet fields, we
demonstrated the existence of free fermionic heterotic-string models in which
the SU(3)_C x SU(2)_L x U(1)_Y-charged matter spectrum, just below the string
scale, consists solely of the MSSM spectrum. In this paper we generalize the
analysis to include VEVs of non-Abelian fields. We find several,
MSSM-producing, exact non-Abelian flat directions, which are the first such
examples in the literature. We examine the possibility that hidden sector
condensates lift the flat directions.

</DOC>
<DOC>
<DOCNO> 11425 </DOCNO>
Many-Electron wave function and momentum density


  Summary for the review talk on recent progress in the theoretical studies of
electron momentum density distribution at the Sagamore XIII conference (Stare
Jablonki, Poland; September 3-9, 2000).

</DOC>
<DOC>
<DOCNO> 117242 </DOCNO>
Correlation consistent valence basis sets for use with the


  We propose large-core correlation-consistent pseudopotential basis sets for
the heavy p-block elements Ga-Kr and In-Xe. The basis sets are of cc-pVTZ and
cc-pVQZ quality, and have been optimized for use with the large-core
(valence-electrons only) Stuttgart-Dresden-Bonn relativistic pseudopotentials.
Validation calculations on a variety of third-row and fourth-row diatomics
suggest them to be comparable in quality to the all-electron cc-pVTZ and
cc-pVQZ basis sets for lighter elements. Especially the SDB-cc-pVQZ basis set
in conjunction with a core polarization potential (CPP) yields excellent
agreement with experiment for compounds of the later heavy p-block elements.
For accurate calculations on Ga (and, to a lesser extent, Ge) compounds,
explicit treatment of 13 valence electrons appears to be desirable, while it
seems inevitable for In compounds. For Ga and Ge, we propose correlation
consistent basis sets extended for (3d) correlation. For accurate calculations
on organometallic complexes of interest to homogenous catalysis, we recommend a
combination of the standard cc-pVTZ basis set for first- and second-row
elements, the presently derived SDB-cc-pVTZ basis set for heavier p-block
elements, and for transition metals, the small-core [6s5p3d] Stuttgart-Dresden
basis set-RECP combination supplemented by (2f1g) functions with exponents
given in the Appendix to the present paper.

</DOC>
<DOC>
<DOCNO> 99600 </DOCNO>
Entropy of automorphisms of II_1-factors arising from the dynamical


  Let a countable amenable group G acts freely and ergodically on a Lebesgue
space (X,mu), preserving the measure mu. If T is an automorphism of the
equivalence relation defined by G then T can be extended to an automorphism
alpha_T of the II_1-factor M=L^\infty(X,\mu)\rtimes G. We prove that if T
commutes with the action of G then H(alpha_T)=h(T), where H(alpha_T) is the
Connes- Stormer entropy of alpha_T, and h(T) is the Kolmogorov-Sinai entropy of
T. We prove also that for given s and t, 0\le s\le t\le\infty, there exists a T
such that h(T)=s and H(alpha_T)=t.

</DOC>
<DOC>
<DOCNO> 68830 </DOCNO>
Can a Large Neutron Excess Help Solve the Baryon Loading Problem in


  We point out that the baryon-loading problem in Gamma-Ray Burst (GRB) models
can be amelioriated if a significant fraction of the baryons which inertially
confine the fireball are converted to neutrons. A high neutron fraction in some
circumstances can result in a reduced transfer of energy from relativistic
light particles in the fireball to baryons. The energy needed to produce the
required relativistic flow in the GRB is consequently reduced, in some cases by
orders of magnitude. This could be relevant to GRB models because a high
neutron-to-proton ratio has been calculated in neutron star-merger fireball
environments. Significant neutron excess also could occur near compact objects
with high neutrino fluxes.

</DOC>
<DOC>
<DOCNO> 118698 </DOCNO>
The best unbiased estimator for the CMB angular bispectrum


  For those angular multipoles where cosmic variance is an issue,
non-Gaussianities in the Cosmic Microwave Background (CMB) anisotropies will be
hard to detect. Here, we construct explicitly the best unbiased estimator for
the CMB angular bispectrum.

</DOC>
<DOC>
<DOCNO> 80812 </DOCNO>
Lattice artefacts and the running of the coupling constant


  We study the running of the L\"uscher-Weisz-Wolff (LWW) coupling constant in
the two dimensional O(3) nonlinear $\sigma$ model. To investigate the continuum
limit we refine the lattice spacing from the $1\over 16$ value used by LWW up
to $1\over 160$. We find that the lattice artefacts are much larger than
estimated by LWW and that most likely the coupling constant runs slower than
predicted by perturbation theory. A precise determination of the running in the
continuum limit would require a controlled ansatz of extrapolation, which, we
argue, is not presently available.

</DOC>
<DOC>
<DOCNO> 120614 </DOCNO>
The redshift and the ordinary host galaxy of GRB 970228


  The gamma-ray burst of 28 February 1997 (GRB 970228) ushered in the discovery
of the afterglow phenomenon. Despite intense study of the host galaxy, however,
the nature of the host and the distance to the burst eluded the community. Here
we present the measurement of the redshift of GRB 970228, and, based on its
spectroscopic and photometric properties, identify the host as an
underluminous, but otherwise normal galaxy at redshift z=0.695 undergoing a
modest level of star formation. At this redshift, the GRB released an isotropic
equivalent energy of E = (6.8 +/- 0.5) x 10^51 erg [30-2000 keV restframe]. We
find no evidence that the host is much bluer or forming stars more rigorously
than the general field population. In fact, by all accounts in our analysis
(color-magnitude, magnitude-radius, star-formation rate, Balmer-break
amplitude) the host properties appear typical for faint blue field galaxies at
comparable redshifts.

</DOC>
<DOC>
<DOCNO> 9011 </DOCNO>
Bose-Einstein condensation in a two-dimensional trap


  The theory of Bose-Einstein condensation in a two-dimensional(2D) harmonic
trap is developed from 2D Gross-Pitaevskii equation. The 2D interaction
strength is obtained from a 2D collision theory.
 We show the realization of 2D condensation of trapped Bose atoms directly by
obtaining the stable solutions for the condensate wave function from the 2D
Gross-Pitaevskii equation. We calculate the ground-state energy of the 2D
system, and also the wave function of the 2D vortex state. In particular, the
2D energy state becomes less stable than the 3D case with the number of trapped
atoms. The results of the 2D Bose condensation are also compared with those of
the well-known 3D case.

</DOC>
<DOC>
<DOCNO> 10527 </DOCNO>
Nonlinear sigma model approach for chiral fluctuations and symmetry


  In this paper we discuss symmetry breakdown in NJL model at low N_c. In
particular we propose a modified NJL model that displays a symmetry breakdown
and also at finite temperatures under certain conditions the chiral
fluctuations in this model give rise to a phase analogous to pseudogap phase of
strong-coupling and low carrier density superconductors.

</DOC>
<DOC>
<DOCNO> 39747 </DOCNO>
A Search for Lightly Ionizing Particles with the MACRO Detector


  A search for lightly ionizing particles has been performed with the MACRO
detector. This search was sensitive to particles with charges between
$\fractional{5}$$e$ and close to the charge of an electron, with $\beta$
between approximately 0.25 and 1.0. Unlike previous searches both single track
events and tracks buried within high multiplicity muon showers were examined.
  In a period of approximately one year no candidates were observed. Assuming
an isotropic flux, for the single track sample this corresponds to a 90% C.L.
upper flux limit $\Phi \leq 9.2 \times 10^{-15} cm^{-2} sec^{-1} sr^{-1}$ .

</DOC>
<DOC>
<DOCNO> 13872 </DOCNO>
Traffic and Related Self-Driven Many-Particle Systems


  Since the subject of traffic dynamics has captured the interest of
physicists, many astonishing effects have been revealed and explained. Some of
the questions now understood are the following: Why are vehicles sometimes
stopped by so-called ``phantom traffic jams'', although they all like to drive
fast? What are the mechanisms behind stop-and-go traffic? Why are there several
different kinds of congestion, and how are they related? Why do most traffic
jams occur considerably before the road capacity is reached? Can a temporary
reduction of the traffic volume cause a lasting traffic jam? Under which
conditions can speed limits speed up traffic? Why do pedestrians moving in
opposite directions normally organize in lanes, while similar systems are
``freezing by heating''? Why do self-organizing systems tend to reach an
optimal state? Why do panicking pedestrians produce dangerous deadlocks? All
these questions have been answered by applying and extending methods from
statistical physics and non-linear dynamics to self-driven many-particle
systems. This review article on traffic introduces (i) empirically data, facts,
and observations, (ii) the main approaches to pedestrian, highway, and city
traffic, (iii) microscopic (particle-based), mesoscopic (gas-kinetic), and
macroscopic (fluid-dynamic) models. Attention is also paid to the formulation
of a micro-macro link, to aspects of universality, and to other unifying
concepts like a general modelling framework for self-driven many-particle
systems, including spin systems. Subjects such as the optimization of traffic
flows and relations to biological or socio-economic systems such as bacterial
colonies, flocks of birds, panics, and stock market dynamics are discussed as
well.

</DOC>
<DOC>
<DOCNO> 85366 </DOCNO>
Gluing 4-simplices: a derivation of the Barrett-Crane spin foam model


  We derive the the Barrett-Crane spin foam model for Euclidean 4 dimensional
quantum gravity from a discretized BF theory, imposing the constraints that
reduce it to gravity at the quantum level. We obtain in this way a precise
prescription of the form of the Barrett-Crane state sum, in the general case of
an arbitrary manifold with boundary. In particular we derive the amplitude for
the edges of the spin foam from a natural procedure of gluing different
4-simplices along a common tetrahedron. The generalization of our results to
higher dimensions is also shown.

</DOC>
<DOC>
<DOCNO> 102760 </DOCNO>
Moments of inertia associated with the lozenge tilings of a hexagon


  Consider the probability that an arbitrary chosen lozenge tiling of the
hexagon with side lengths a, b, c, a, b, c contains the horizontal lozenge with
lowest vertex (x,y) as if it described the distribution of mass in the plane.
We compute the horizontal and the vertical moments of inertia with respect to
this distribution. This solves a problem by Propp [1, Problem 7].

</DOC>
<DOC>
<DOCNO> 7904 </DOCNO>
Continuum field description of crack propagation


  We develop continuum field model for crack propagation in brittle amorphous
solids. The model is represented by equations for elastic displacements
combined with the order parameter equation which accounts for the dynamics of
defects. This model captures all important phenomenology of crack propagation:
crack initiation, propagation, dynamic fracture instability, sound emission,
crack branching and fragmentation.

</DOC>
<DOC>
<DOCNO> 68057 </DOCNO>
Effects of a general set of interactions on neutrino propagation in


  This talk is based on the article hep-ph/9903517 written in collaboration
with Sven Bergmann and Yuval Grossman. An analysis of the effective potential
for neutrino propagation in matter, assuming a generic set of Lorentz invariant
non-derivative interactions is presented. In addition to vector and axial
vector couplings, also tensor interactions can give coherent effects if the
medium is polarized, and the components of a tensor potential transverse to the
direction of neutrino propagation can induce a neutrino spin-flip.

</DOC>
<DOC>
<DOCNO> 7750 </DOCNO>
Microscopic theory of the coupling of intrinsic Josephson oscillations


  A microscopic theory for the coupling of intrinsic Josephson oscillations and
dispersive phonon branches in layered superconductors is developed. Thereby the
effect of phonons on the electronic c-axis transport enters through an
effective longitudinal dielectric function. This coupling provides an
explanation of recently observed subgap resonances in the $I_{dc}$-$V_{dc}$-
curve of anisotropic cuprate superconductors forming a stack of short Josephson
junctions. Due to the finite dispersion these resonances can appear at
van-Hove-singularities of both optical and acoustical phonon branches,
explaining low-voltage structures in the I-V-characteristic, which are not
understood in phonon models without dispersion. In long junctions the
dispersion of collective electron-phonon modes parallel to the layers is
investigated.

</DOC>
<DOC>
<DOCNO> 13469 </DOCNO>
Characterization of the frequency of extreme events by the Generalized


  Based on recent results in extreme value theory, we use a new technique for
the statistical estimation of distribution tails. Specifically, we use the
Gnedenko-Pickands-Balkema-de Haan theorem, which gives a natural limit law for
peak-over-threshold values in the form of the Generalized Pareto Distribution
(GPD). Useful in finance, insurance, hydrology, we investigate here the
earthquake energy distribution described by the Gutenberg-Richter seismic
moment-frequency law and analyze shallow earthquakes (depth h < 70 km) in the
Harvard catalog over the period 1977-2000 in 18 seismic zones. The whole GPD is
found to approximate the tails of the seismic moment distributions quite well
above moment-magnitudes larger than mW=5.3 and no statistically significant
regional difference is found for subduction and transform seismic zones. We
confirm that the b-value is very different in mid-ocean ridges compared to
other zones (b=1.50=B10.09 versus b=1.00=B10.05 corresponding to a power law
exponent close to 1 versus 2/3) with a very high statistical confidence. We
propose a physical mechanism for this, contrasting slow healing ruptures in
mid-ocean ridges with fast healing ruptures in other zones. Deviations from the
GPD at the very end of the tail are detected in the sample containing
earthquakes from all major subduction zones (sample size of 4985 events). We
propose a new statistical test of significance of such deviations based on the
bootstrap method. The number of events deviating from the tails of GPD in the
studied data sets (15-20 at most) is not sufficient for determining the
functional form of those deviations. Thus, it is practically impossible to give
preference to one of the previously suggested parametric families describing
the ends of tails of seismic moment distributions.

</DOC>
<DOC>
<DOCNO> 170262 </DOCNO>
Photon localization and vacuum noise in optical measurements


  Description of detection and emission in terms of the photon localization is
discussed. It is shown that the standard representation of plane waves of
photons should be revised to take into consideration the boundary conditions
caused by the presence of quantum emitters and detectors. In turn, the change
of the boundary conditions causes spatially inhomogeneous structure of the
electromagnetic vacuum which leads to the increase of the vacuum noise over the
level predicted in the frame of the model of plane photons.

</DOC>
<DOC>
<DOCNO> 118702 </DOCNO>
Correlated mixtures of adiabatic and isocurvature cosmological


  The Cosmic Microwave Background (CMB) anisotropies measurements can provide
many clues about the Universe. Although the common belief is that they will
allow a very precise measurement of the cosmological parameters (that is, the
current state of the Universe), they will alternatively give interesting
informations about the state of the initial perturbations (that is, the state
of the Universe at the end of inflation). In this paper, we study the
observational consequences on the CMB anisotropies of some wide set of inital
conditions, with a correlated mixture of adiabatic and isocurvature
perturbations.

</DOC>
<DOC>
<DOCNO> 7853 </DOCNO>
The Magnetic Excitation Spectrum and Thermodynamics of High-$T_c$


  Inelastic neutron scattering was used to study the wavevector- and
frequency-dependent magnetic fluctuations in single crystals of superconducting
YBa$_2$Cu$_3$O$_{6+x}$. The spectra contain several important features,
including a gap in the superconducting state, a pseudogap in the normal state
and the much-discussed resonance peak. The appearance of the pseudogap
determined from transport and nuclear resonance coincides with formation of the
resonance in the magnetic excitations. The exchange energy associated with the
resonance has the temperature and doping dependences as well as the magnitude
to describe approximately the electronic specific heat near the superconducting
transition temperature ($T_c$).

</DOC>
<DOC>
<DOCNO> 120084 </DOCNO>
Self-Interacting Dark Matter


  Spergel and Steinhardt have recently proposed the concept of dark matter with
strong self-interactions as a means to address numerous discrepancies between
observations of dark matter halos on subgalactic scales and the predictions of
the standard collisionless dark matter picture. We review the motivations for
this scenario and discuss some recent, successful numerical tests. We also
discuss the possibility that the dark matter interacts strongly with ordinary
baryonic matter, as well as with itself. We present a new analysis of the
experimental constraints and re-evaluate the allowed range of cross-section and
mass.

</DOC>
<DOC>
<DOCNO> 120606 </DOCNO>
Empirical Verification of the Fe II Oscillator Strengths in the FUSE


  We report empirical determinations of atomic oscillator strengths, or
f-values, for 11 ground-state transitions of Fe II in the wavelength range 1050
to 1150 Ang. We use ultraviolet absorption line observations of interstellar
material towards stars in the Galaxy and the Magellanic Clouds taken with
Copernicus, the Goddard High Resolution Spectrograph on-board the Hubble Space
Telescope, and the Far Ultraviolet Spectroscopic Explorer. We derive absolute
oscillator strengths by a combination of the apparent optical depth, component
fitting, and curve-of-growth fitting techniques. Our derived oscillator
strengths are generally in excellent agreement with recent theoretical
calculations by Raassen & Uylings using the orthogonal operator technique.
However, we identify three of the eleven transitions studied here whose
f-values seem to be incompatible with these calculations, by as much as a
factor of two. We suggest revisions to these f-values based upon our analysis.

</DOC>
<DOC>
<DOCNO> 117221 </DOCNO>
A Monitor of Beam Polarization Profiles for the TRIUMF Parity Experiment


  TRIUMF experiment E497 is a study of parity violation in pp scattering at an
energy where the leading term in the analyzing power is expected to vanish,
thus measuring a unique combination of weak-interaction flavour conserving
terms. It is desired to reach a level of sensitivity of 2x10^-8 in both
statistical and systematic errors. The leading systematic errors depend on
transverse polarization components and, at least, the first moment of
transverse polarization. A novel polarimeter that measures profiles of both
transverse components of polarization as a function of position is described.

</DOC>
<DOC>
<DOCNO> 117897 </DOCNO>
New Dark Matter Physics: Clues from Halo Structure


  We examine the effect of primordial dark matter velocity dispersion and/or
particle self-interactions on the structure and stability of galaxy halos,
especially with respect to the formation of substructure and central density
cusps. Primordial velocity dispersion is characterised by a ``phase density''
$Q\equiv \rho/<v^2>^{3/2}$, which for relativistically-decoupled relics is
determined by particle mass and spin and is insensitive to cosmological
parameters. Finite $Q$ leads to small-scale filtering of the primordial power
spectrum, which reduces substructure, and limits the maximum central density of
halos, which eliminates central cusps. The relationship between $Q$ and halo
observables is estimated. The primordial $Q$ may be preserved in the cores of
halos and if so leads to a predicted relation, closely analogous to that in
degenerate dwarf stars, between the central density and velocity dispersion.
Classical polytrope solutions are used to model the structure of halos of
collisional dark matter, and to show that self-interactions in halos today are
probably not significant because they destabilize halo cores via heat
conduction. Constraints on masses and self-interactions of dark matter
particles are estimated from halo stability and other considerations.

</DOC>
<DOC>
<DOCNO> 152497 </DOCNO>
Twisted K-homology theory, twisted Ext-theory


  These are notes on twisted K-homology theory and twisted Ext-theory from the
C*-algebra viewpoint, part of a series of talks on ``C*-algebras,
noncommutative geometry and K-theory'', primarily for physicists.

</DOC>
<DOC>
<DOCNO> 169723 </DOCNO>
Quantum searching with continuous variables


  A fast quantum search algorithm for continuous variables is presented. The
result is the quantum continuous variable analog of Grover's algorithm
originally proposed for qubits. A continuous variable analog of the Hadamard
(i.e., Fourier transform) operation is used in conjunction with inversion about
the average of quantum states to allow the approximate identification of an
unknown quantum state in a way that gives a square-root speed-up over search
algorithms using classical continuous variables. Also, we show that this
quantum search algorithm is robust for a generalised Fourier transformation on
continuous variables.

</DOC>
<DOC>
<DOCNO> 10727 </DOCNO>
Flow equation approach to the sine-Gordon model


  A continuous sequence of infinitesimal unitary transformations is used to
diagonalize the quantum sine-Gordon model for \beta^2\in(2\pi,\infty). This
approach can be understood as an extension of perturbative scaling theory since
it links weak- to strong-coupling behavior in a systematic expansion: a small
expansion parameter is identified and this parameter remains small throughout
the entire flow unlike the diverging running coupling constant of perturbative
scaling. Our approximation consists in neglecting higher orders in this small
parameter. We find very accurate results for the single-particle/hole spectrum
in the strong-coupling phase and can describe the full crossover from weak to
strong-coupling. The integrable structure of the sine-Gordon model is not used
in our approach. Our new method should be of interest for the investigation of
nonintegrable perturbations and for other strong-coupling problems.

</DOC>
<DOC>
<DOCNO> 119609 </DOCNO>
Star cluster ecology IVa: Dissection of an open star


  The evolution of star clusters is studied using N-body simulations in which
the evolution of single stars and binaries are taken self-consistently into
account. Initial conditions are chosen to represent relatively young Galactic
open clusters, such as the Pleiades, Praesepe and the Hyades. The calculations
include a realistic mass function, primordial binaries and the external
potential of the parent Galaxy. Our model clusters are generally significantly
flattened in the Galactic tidal field, and dissolve before deep core collapse
occurs. The binary fraction decreases initially due to the destruction of soft
binaries, but increases later because lower mass single stars escape more
easily than the more massive binaries. At late times, the cluster core is quite
rich in giants and white dwarfs. There is no evidence for preferential
evaporation of old white dwarfs, on the contrary the formed white dwarfs are
likely to remain in the cluster. Stars tend to escape from the cluster through
the first and second Lagrange points, in the direction of and away from the
Galactic center. Mass segregation manifests itself in our models well within an
initial relaxation time. As expected, giants and white dwarfs are much more
strongly affected by mass segregation than main-sequence stars. Open clusters
are dynamically rather inactive. However, the combined effect of stellar mass
loss and evaporation of stars from the cluster potential drives its dissolution
on a much shorter timescale than if these effects are neglected. The often-used
argument that a star cluster is barely older than its relaxation time and
therefore cannot be dynamically evolved is clearly in error for the majority of
star clusters.

</DOC>
<DOC>
<DOCNO> 122039 </DOCNO>
The Impact of Galaxy Formation on the Diffuse Background Radiation


  The far infrared background is a sink for the hidden aspects of galaxy
formation. At optical wavelengths, ellipticals and spheroids are old, even at
$z \sim 1.$ Neither the luminous formation phase nor their early evolution is
seen in the visible. We infer that ellipticals and, more generally, most
spheroids must have formed in dust-shrouded starbursts. In this article, we
show how separate tracking of disk and spheroid star formation enables us to
infer that disks dominate near the peak in the cosmic star formation rate at $z
\lapproxeq 2$ and in the diffuse ultraviolet/optical/infrared background,
whereas spheroid formation dominates the submillimetre background.

</DOC>
<DOC>
<DOCNO> 85348 </DOCNO>
Quantum, Gravity, and Geometry


  Recently, it is shown that, the quantum effects of matter are well described
by the conformal degree of freedom of the space-time metric. On the other hand,
it is a wellknown fact that according to Einstein's gravity theory, gravity and
geometry are interconnected. In the new quantum gravity theory, matter quantum
effects completely determine the conformal degree of freedom of the space-time
metric, while the causal structure of the space-time is determined by the
gravitational effects of the matter, as well as the quantum effects through
back reaction effects. This idea, previousely, is realized in the framework of
scalar-tensor theories. In this work, it is shown that quantum gravity theory
can also be realized as a purely metric theory. Such a theory is developed, its
consequences and its properties are investigated. The theory is applied, then,
to black holes and the radiation-dominated universe. It is shown that the
initial singularity can be avoided.

</DOC>
<DOC>
<DOCNO> 118598 </DOCNO>
Topological defects: fossils of an anisotropic era?


  We consider the evolution of domain walls produced during an anisotropic
phase in the very early universe, showing that the resulting network can be
very anisotropic. If the domain walls are produced during an inflationary era,
the network will soon freeze out in comoving coordinates retaining the imprints
of the anisotropic regime, even though inflation makes the universe isotropic.
Only at late times, when the typical size of the major axis of the domain walls
becomes smaller than the Hubble radius, does the network evolve rapidly towards
isotropy. Hence, we may hope to see imprints of the anisotropic era if by today
the typical size of the major axis of the domain walls is of the order of the
Hubble radius, or if the walls re-entered it only very recently. Depending on
the mass scale of the domain walls, there is also the possibility that they
re-enter at earlier times, but their evolution remains friction-dominated until
recently, in which case the signatures of the anisotropic era will be much
better preserved. These effects are expected to occur in generic topological
defect models.

</DOC>
<DOC>
<DOCNO> 39844 </DOCNO>
Is the Polarized Antiquark Sea in the Nucleon Flavor Symmetric?


  We show that the model which naturally explains the $\bar u \ne \bar d$
asymmetry in the nucleon and is in quantitative agreement with the Gottfried
sum rule data, also predicts that in the proton $\Delta \bar u > 0 > \Delta
\bar s > \Delta \bar d$ and $\Delta \bar u - \Delta \bar d > \bar d - \bar u >
0$. At the input scale, these results can be derived even analytically. Thus
the violation of the flavor symmetry is more serious in the polarized case than
in the unpolarized case. In contrast, many recent analyses of the polarized
data have made a simplifying assumption that all the three $\Delta \bar q$'s
have the same sign and magnitude. We point out the need to redo these analyses,
allowing for the alternate scenario as described above. We present predictions
of the model for the $W^-$ asymmetry in polarized $pp$ scattering, which can be
tested at RHIC; these are quite different from those available in the
literature.

</DOC>
<DOC>
<DOCNO> 119935 </DOCNO>
A cloud model of active galactic nuclei: the iron K-alpha line


  The origin and the profile of the iron K-alpha line from active galactic
nuclei is being studied. The model with a quasi-spherical distribution of
clouds around a compact galactic nucleus is explored in which the intrinsic
spectral feature around 6-7 keV is substantially affected by Comptonization of
primary X-rays. The predicted spectral profiles are influenced mainly by motion
of the clouds in strong gravitational field of the centre, and by orientation
of the source with respect to the observer. The case of the Seyfert galaxy
MCG-6-30-15 is examined in more detail and free parameters of the model are
determined. A robust result is obtained: acceptable fits to the observed
profile correspond to the spherical distribution of the clouds with strong
self-obscuration effects and with rather high value of ionization parameter.
This is a different situation from that considered in the model of a cold
illuminated disc. Nevertheless, geometrically flat (disc-type) configurations
are not rejected.

</DOC>
<DOC>
<DOCNO> 150632 </DOCNO>
Hyperkahler Singularities in Superstrings Compactification and 2d N=4


  We study the singularities of the Higgs branch of supersymmetric U(1)^r gauge
theories with eight supercharges. We derive new solutions for the moduli space
of vacua preserving manifestly the eight supercharges by using a geometric
realization of the SU(2)_R symmetry and a separation procedure of the gauge and
SU(2)_R charges, which allow us to put the hypermultiplet vacua in a form
depending on a parameter $\gamma$. For $\gamma=1$, we obtain new models which
flow in the infrared to 2d N=(4,4) conformal models and we show that the
classical moduli spaces are given by intersecting cotangent weighted complex
projective spaces containing the small instanton singularity, discussed in
[17], as a leading special case. We also make comments regarding the d$2d N=4
conformal Liouville description of the Higgs branch throat by following the
analysis of [18]. Other features are also discussed.

</DOC>
<DOC>
<DOCNO> 84721 </DOCNO>
Maximal Acceleration Effects in Reissner-Nordstrom Space


  The dynamics of a relativistic particle in a Reissner-Nordstrom background is
studied using Caianiello model with maximal acceleration. The behaviour of the
particle, embedded in a new effective geometry, changes with respect to the
classical scenario because of the formation of repulsive potential barriers
near the horizon. Black hole formation by accretion of massive particles is not
therefore a viable process in the model. At the same time, the naked
singularity remains largely unaffected by maximal acceleration corrections.

</DOC>
<DOC>
<DOCNO> 68924 </DOCNO>
Proposal to observe the strong Van der Waals force in the low energy


  In the neutron-Pb scattering in the MeV. region, existence of the long range
interaction has been known and people have hopefully expected to understand it
as the effect of the electric polarization of the neutron. However the precise
determination of $\alpha_{n}$ in the very low energy region indicates that the
polarizability of the neutron $\alpha_{n}$ is around two order of magnitude
smaller compared to what is expected in the phenomena in the MeV. region. We
need another strong long range potential which decreases faster than $r^{-4}$.
On the other hand, analysis of the low energy proton-proton data revealed the
existence of the strong long range potential whose tail was $V(r) \sim
-C/r^{\alpha}$ with $\alpha=6.08$. The neuton-nucleus scattering is a good
place to see such a force, since the strength $C$ is magnified by factor $A$,
the mass number. Using the long range parameters obtained in p-p, we predict
the characteristic angular dependency of the n-Pb amplitude for fixed energy.
Appearance of a cusp at $\nu=0$, which points upward, in the once subtracted
P-wave amplitude $a_{1}(\nu)/\nu$ is predicted.

</DOC>
<DOC>
<DOCNO> 119342 </DOCNO>
Distinguishing RBL-like objects and XBL-like objects with the peak


  We investigate quantitatively how the peak emission frequency of the overall
energy spectrum is at work in distinguishing RBL-like and XBL-like objects. We
employ the sample of Giommi et al. (1995) to study the distribution of BL
Lacertae objects with various locations of the cutoff of the overall energy
spectrum. We find that the sources with the cutoff located at lower frequency
are indeed sited in the RBL region of the $\alpha_{ro}-\alpha_{ox}$ plane,
while those with the cutoff located at higher frequency are distributed in the
XBL region. For a more quantitative study, we employ the BL Lacertae samples
presented by Sambruna et al. (1996), where, the peak emission frequency, $\nu
_p$, of each source is estimated by fitting the data with a parabolic function.
In the plot of $\alpha_{rx}-\log \nu_p$ we find that, in the four different
regions divided by the $\alpha_{rx}=0.75$ line and the $\log \nu_p=14.7$ line,
all the RBL-like objects are inside the upper left region, while most XBL-like
objects are within the lower right region. A few sources are located in the
lower left region. No sources are in the upper right region. This result is
rather quantitative. It provides an evidence supporting what Giommi et al.
(1995) suggested: RBL-like and XBL-like objects can be distinguished by the
difference of the peak emission frequency of the overall energy spectrum.

</DOC>
<DOC>
<DOCNO> 70187 </DOCNO>
From Minimal to Realistic Supersymmetric SU(5) Grand Unification


  We construct and discuss a "realistic" example of SUSY SU(5) GUT model, with
an additional U(1) flavour symmetry, that is not plagued by the need of large
fine tunings, like those associated with doublet-triplet splitting in the
minimal model, and that leads to an acceptable phenomenology. This includes
coupling unification with a value of alpha_s(m_Z) in much better agreement with
the data than in the minimal version, an acceptable hierarchical pattern for
fermion masses and mixing angles, also including neutrino masses and mixings,
and a proton decay rate compatible with present limits (but the discovery of
proton decay should be within reach of the next generation of experiments). In
the neutrino sector the preferred solution is one with nearly maximal mixing
both for atmospheric and solar neutrinos.

</DOC>
<DOC>
<DOCNO> 8765 </DOCNO>
Topological Defects in Size-Dispersed Solids


  We study the behavior of the topological defects in the inherent structures
of a two-dimensional binary Lennard-Jones system as the size dispersity varies.
We find that topological defects arising from the particle size dispersity are
responsible for destabilizing the solid as follows: (i) for particle density
$\rho \leq 0.9$, the solid melts through intermediate states of decreasing
hexatic order arising from the proliferation of unbounded dislocations, (ii)
for $\rho > 0.9$, the dislocations form grain boundaries, dividing the system
into micro-crystallites and destroying the translational and orientational
order.

</DOC>
<DOC>
<DOCNO> 122529 </DOCNO>
Test particle acceleration by rotating jet magnetospheres


  Centrifugal acceleration of charged test particles at the base of a rotating
jet magnetosphere is considered. Based on an analysis of forces we derive the
equation for the radial accelerated motion and present an analytical solution.
It is shown that for particles moving outwards along rotating magnetic field
lines, the energy gain is in particular limited by the breakdown of the
bead-on-the-wire approximation which occurs in the vicinity of the light
cylinder $r_{L}$. The corresponding upper limit for the maximum Lorentz factor
$\gamma_{max}$ for electrons scales $\propto B^{2/3} r_{L}^{2/3}$, with $B$ the
magnetic field strength at $r_{L}$, and is at most of the order of a
$10^2-10^3$ for the conditions regarded to be typical for BL Lac objects. Such
values suggest that this mechanism may provide pre-accelerated seed particles
which are required for efficient Fermi-type particle acceleration at larger
scales in radio jets.

</DOC>
<DOC>
<DOCNO> 99983 </DOCNO>
Quantum Lefschetz Hyperplane Theorem


  The mirror theorem is generalized to any smooth projective variety X. That
is, a fundamental relation between the Gromov-Witten invariants of X and
Gromov-Witten invariants of complete intersections Y in X is established.

</DOC>
<DOC>
<DOCNO> 101049 </DOCNO>
Neural Stabilization/Excitation Control of a High-Order Power System by


  This paper discusses the systematic design of an adaptive feedback
linearizing neurocontroller for a high-order model of the synchronous
machine/infinite bus power system. The power system is first modelled as an
input-output nonlinear discrete-time system approximated by two neural
networks. The approach allows a simple linear pole-placement controller (which
is itself not a neural network) to be designed. The control law is specified
such that the controller adaptively calculates an appropriate feedback
linearizing control law at each sampling instant by utilizing plant parameter
estimates provided by the neural system model. The control system also adapts
itself on-line. This avoids the requirement for exact knowledge of the power
system dynamics and full state measurement as well as other difficulties
associated with implementing analytical input-output feedback linearizing
control for a complex power system model. Furthermore, a departure is made from
the `ad hoc' manner in which many neural controllers have been designed for
power systems; the approach used here has foundations in control theoretic
concepts of adaptive feedback linearization and pole-placement control design.
  Simulation results demonstrate the performance of this controller for a
representative example of a single-machine/infinite bus power system
configuration under various operational conditions.

</DOC>
<DOC>
<DOCNO> 10379 </DOCNO>
Theory of Distinct Crystal Structures of Polymerized Fullerides AC60,


  The polymer phases of AC60 form distinct crystal structures characterized by
the mutual orientations of the (C60-)n chains. We show that the direct electric
quadrupole interaction between chains always favors the orthorhombic structure
Pmnn with alternating chain orientations. However the specific quadrupolar
polarizability of the alkali metal ions leads to an indirect interchain
coupling which favors the monoclinic structure I2/m with equal chain
orientations. The competition between direct and indirect interactions explains
the structural difference between KC60 and RbC60, CsC60.

</DOC>
<DOC>
<DOCNO> 9373 </DOCNO>
Dynamic critical behavior of cluster algorithms for 2D Ashkin-Teller and


  We study the dynamic critical behavior of two algorithms: the Swendsen-Wang
algorithm for the two-dimensional Potts model with q=2,3,4 and a
Swendsen-Wang-type algorithm for the two-dimensional symmetric Ashkin-Teller
model on the self-dual curve. We find that the Li--Sokal bound on the
autocorrelation time \tau_{{\rm int},{\cal E}} \geq const \times C_H is almost,
but not quite sharp. The ratio \tau_{{\rm int},{\cal E}}/C_H appears to tend to
infinity either as a logarithm or as a small power (0.05 \ltapprox p \ltapprox
0.12). We also show that the exponential autocorrelation time \tau_{{\rm
exp},{\cal E}} is proportional to the integrated autocorrelation time
\tau_{{\rm int},{\cal E}}.

</DOC>
<DOC>
<DOCNO> 152090 </DOCNO>
Towards a 3D reduction of the N-body Bethe-Salpeter equation


  Starting with the homogeneous Bethe-Salpeter equation for two fermions, we
perform a 3D reduction using a series expansion around an unspecified
positive-energy instantaneous approximation of the kernel. A second series
expansion is made, at the 3D level, in order to get an "hermitian" potential.
The combination of both series gives a very simple result, which does not
depend of the initial approximation of the kernel anymore, and could be
obtained directly by starting with an approximation of the free propagator. The
generalisation of this result to a system of f (=0,...N) fermions and N-f
bosons is easy.

</DOC>
<DOC>
<DOCNO> 9352 </DOCNO>
Weakly Interacting Bose-Einstein Condensates Under Rotation: Mean-field


  We consider a weakly-interacting, harmonically-trapped Bose-Einstein
condensed gas under rotation and investigate the connection between the
energies obtained from mean-field calculations and from exact diagonalizations
in a subspace of degenerate states. From the latter we derive an approximation
scheme valid in the thermodynamic limit of many particles. Mean-field results
are shown to emerge as the correct leading-order approximation to exact
calculations in the same subspace.

</DOC>
<DOC>
<DOCNO> 150476 </DOCNO>
Gravity and the Newtonian limit in the Randall-Sundrum model


  We point out that the gravitational evolution equations in the
Randall-Sundrum model appear in a different form than hitherto assumed. As a
consequence, the model yields a correct Newtonian limit in a novel manner.

</DOC>
<DOC>
<DOCNO> 7831 </DOCNO>
Field distributions and effective-medium approximation for weakly


  An effective-medium theory is proposed for random weakly nonlinear dielectric
media. It is based on a new gaussian approximation for the probability
distributions of the electric field in each component of a multi-phase
composite. These distributions are computed to linear order from a
Bruggeman-like self-consistent formula. The resulting effective-medium formula
for the nonlinear medium reduces to Bruggeman's in the linear case. It is exact
up to second order in a weak-disorder expansion, and close to the exact result
in the dilute limit (in particular, it is exact for d=1 and d=infinity. In a
high contrast situation, the noise exponents are kappa=kappa'=0 near the
percolation threshold. Numerical results are provided for different weak
nonlinearities.

</DOC>
<DOC>
<DOCNO> 122595 </DOCNO>
The helicity constraint in turbulent dynamos with shear


  The evolution of magnetic fields is studied using simulations of forced
helical turbulence with strong imposed shear. After some initial exponential
growth, the magnetic field develops a large scale travelling wave pattern. The
resulting field structure possesses magnetic helicity, which is conserved in a
periodic box by the ideal MHD equations and can hence only change on a
resistive time scale. This constrains strongly the growth time of the large
scale magnetic field, but less strongly the length of the cycle period.
Comparing with the case without shear, the time scale for large scale field
amplification is shortened by a factor Q, which depends on the relative
importance of shear and helical turbulence, and which controls also the ratio
of toroidal to poloidal field. The results of the simulations can be reproduced
qualitatively and quantitatively with a mean-field alpha-Omega dynamo model
with alpha-effect and the turbulent magnetic diffusivity coefficients that are
less strongly quenched than in the corresponding alpha^2-dynamo.

</DOC>
<DOC>
<DOCNO> 170200 </DOCNO>
Comment on "Thermal Effects on the Casimir Force in the 0.1-5 micrometer


  In a recent paper (M. Bostrom and Bo E. Sernelius, Phys. Rev. Lett. 84, 4757
(2000)) the combined effect of finite conductivity and finite temperature on
the Casimir force is analyzed, and significant deviations from other
theoretical results and a recent experiment are obtained.
  In this Comment, I show that the extrapolation to zero frequency is incorrect
because the authors have neglected that the wavenumber and frequency of the
electromagentic mode must simultaneously appraoch zero

</DOC>
<DOC>
<DOCNO> 116418 </DOCNO>
The Hawking-Unruh Temperature and Damping in a Linear Focusing Channel


  The Hawking-Unruh effective temperature, hbar a* / 2 pi c k, due to quantum
fluctuations in the radiation of an accelerated charged-particle beam can be
used to show that transverse oscillations of the beam in a practical linear
focusing channel damp to the quantum-mechanical limit. A comparison is made
between this behavior and that of beams in a wiggler.

</DOC>
<DOC>
<DOCNO> 80618 </DOCNO>
Understanding stochastic perturbation theory: toy models and statistical


  The numerical stochastic perturbation method based on Parisi-Wu quantisation
is applied to a suite of simple models to test its validity at high orders.
Large deviations from normal distribution for the basic estimators are
systematically found in all cases (``Pepe effect''). As a consequence one
should be very careful in estimating statistical errors. We present some
results obtained on Weingarten's ``pathological'' model where reliable results
can be obtained by an application of the bootstrap method. We also present some
evidence that in the far less trivial application to Lattice Gauge Theory a
similar problem should not arise at moderately high loops (up to
O(\alpha^{10})).

</DOC>
<DOC>
<DOCNO> 100074 </DOCNO>
Explicit upper bound for the Weil-Petersson volumes


  An explicit upper bound for the Weil-Petersson volumes of the moduli spaces
of punctured Riemann surfaces is obtained, using Penner's combinatorial
integration scheme with embedded trivalent graphs. It is shown that for a fixed
number of punctures n and for genus g going to infinity, the Weil-Petersson
volume of M_{g,n} has an upper bound c^g g^{2g}. Here c is an independent of n
constant, which is given explicitly.

</DOC>
<DOC>
<DOCNO> 150747 </DOCNO>
Disentangling Intertwined Embedded States and Spin Effects in


  Naive light-front quantization, carried out by a light-front energy
integration of covariant amplitudes, is not guaranteed to generate the
corresponding Feynman amplitudes. In an explicit example we show that the
nonvalence contribution to the minus-component of the EM current of a meson
with fermion constituents has a persistent end-point singularity. Only after
this term is subtracted, the result is covariant and satisfies current
conservation. If the spin-1/2 constituents are replaced by spin zero ones, the
singularity does not occur and the result is, without any adjustment, identical
to the Feynman amplitude. Numerical estimates of valence and nonvalence
contributions are presented for the cases of fermion and boson constituents.

</DOC>
<DOC>
<DOCNO> 120644 </DOCNO>
Noise-driven evolution in stellar systems: Theory


  We present a theory for describing the evolution of a galaxy caused by
stochastic events such as weak mergers, transient spiral structure, orbiting
blobs, etc. This noise excites large-scale patterns that drives the evolution
of the galactic density profile. In dark-matter haloes, the repeated stochastic
perturbations preferentially ring the lowest-order modes of the halo with only
a very weak dependence on the details of their source. Shaped by these modes,
the profile quickly takes on a nearly self-similar form. We show that this form
has the features of the ``universal profile'' reported by Navarro, Frenk, &
White independent of initial conditions in a companion paper. In this sense,
this noise-driven process is a near-equilibrium form of violent relaxation.

</DOC>
<DOC>
<DOCNO> 116847 </DOCNO>
The Physicist's Guide to the Orchestra


  An experimental study of strings, woodwinds (organ pipe, flute, clarinet,
saxophone and recorder), and the voice was undertaken to illustrate the basic
principles of sound production in music instruments. The setup used is simple
and consists of common laboratory equipment. Although the canonical examples
(standing wave on a string, in an open and closed pipe) are easily reproduced,
they fail to explain the majority of the measurements. The reasons for these
deviations are outlined and discussed.

</DOC>
<DOC>
<DOCNO> 68645 </DOCNO>
Supersymmetric Extension of the Standard Model with Naturally Stable


  A new supersymmetric standard model based on N=1 supergravity is constructed,
aiming at natural explanation for the proton stability without invoking an ad
hoc discrete symmetry through R parity. The proton is protected from decay by
an extra U(1) gauge symmetry. Particle contents are necessarily increased to be
free from anomalies, making it possible to incorporate the superfields for
right-handed neutrinos and an SU(2)-singlet Higgs boson. The vacuum expectation
value of this Higgs boson, which induces spontaneous breakdown of the U(1)
symmetry, yields large Majorana masses for the right-handed neutrinos, leading
to small masses for the ordinary neutrinos. The linear coupling of
SU(2)-doublet Higgs superfields, which is indispensable to the superpotential
of the minimal supersymmetric standard model, is replaced by a trilinear
coupling of the Higgs superfields, so that there is no mass parameter in the
superpotential. The energy dependencies of the model parameters are studied,
showing that gauge symmetry breaking is induced by radiative corrections.
Certain ranges of the parameter values compatible with phenomena at the
electroweak energy scale can be derived from universal values of masses-squared
and trilinear coupling constants for scalar fields at a very high energy scale.

</DOC>
<DOC>
<DOCNO> 117709 </DOCNO>
The star formation history as a function of type: constraints from


  Deep galaxy counts are among the best constraints on the cosmic star
formation history (SFH) of galaxies. The evolution of the star formation
activity is followed on a wide range of redshifts (0< z < 4) covering most of
the history of the Universe. Two incompatible interpretations of the
observations are currently competing. After applying star formation rate (SFR)
conversion factors to the CFRS, Halpha or ISO samples, many authors conclude to
a strong increase (~ a factor 10) of the SFR from z=0 to z=1. They also find
some evidence for a peak at z~1 and for a rapid decrease at higher redshifts.
On the other side, the Hawaii deep surveys favor only a mild increase between
z=0 and 1 (Cowie et al., 1996, 1999). To understand the reason for these
discrepant interpretations, we consider three classes of galaxies: E/S0,
Sa-Sb-Sbc, Sc-Sd-Im and bursting dwarfs. We use the new version of our
evolutionary synthesis code, PEGASE which takes into account metallicity and
dust effects. The main results are: i) Late-type galaxies contribute
significantly to the local SFR, especially bursting dwarfs (Fioc and
Rocca-Volmerange, 1999). Because of that, the cosmic SFR can not decrease by a
factor 10 from z=0 to 1. This is in agreement with Cowie's result. ii) The SFR
of intermediate-type galaxies has strongly decreased since z=1. Though the
decrease is less than what find Lilly et al., 1996, this suggests that the CFRS
and Halpha surveys are dominated by such bright early spirals. iii) The
contribution of early-type galaxies increases rapidly from z=1 to their
redshift of formation (> 2-3 for cosmological reasons). Their intense star
formation rates at high-z give strong constraints on early ionization phases,
primeval populations or metal enrichments.(abridged)

</DOC>
<DOC>
<DOCNO> 116869 </DOCNO>
Possibility of a Light Pulse with Speed Greater than c


  In two models it is shown that a light pulse propagates from a vacuum into
certain media with velocity greater than that of a light in a vacuum (c). By
numerical calculation the propagating properties of such a light are given.

</DOC>
<DOC>
<DOCNO> 12460 </DOCNO>
Phase behavior of three-component ionic fluids


  We study the phase behavior of solutions consisting of positive and negative
ions of valence z to which a third ionic species of valence Z>z is added. Using
a discretized Debye-Hueckel theory, we analyze the phase behavior of such
systems for different values of the ratio Z/z. We find, for Z/z>1.934, a
three-phase coexistence region and, for Z/z>2, a closed (reentrant) coexistence
loop at high temperatures. We characterize the behavior of these ternary ionic
mixtures as function of charge asymmetry and temperature, and show the complete
phase diagrams for the experimentally relevant cases of Z/z=2 and Z/z=3,
corresponding to addition of divalent and trivalent ions to monovalent ionic
fluids, respectively.

</DOC>
<DOC>
<DOCNO> 116447 </DOCNO>
Hierarchic Theory of Condensed Matter: Role of water in protein


  1. Role of inter-domain water clusters in large-scale dynamics of proteins;
2. Description of large-scale dynamics of proteins based on generalized
Stokes-Einstein and Eyring-Polany equation; 3. Dynamic model of protein-ligand
complexes formation; 4. The life-time of quasiparticles and frequencies of
their excitation; 5. Mesoscopic mechanism of enzyme catalysis; 6. The mechanism
of ATP hydrolysis energy utilization in muscle contraction and protein
polymerization; 7. Water activity as a regulative factor in the intra- and
inter-cell processes; 8. Water and cancer.

</DOC>
<DOC>
<DOCNO> 120619 </DOCNO>
Rapid State Transitions in the Galactic Black Hole Candidate Source GRS


  We examine the X-ray spectral and temporal behavior of the Galactic black
hole candidate source GRS 1915+105 during its spectral state transition
observed in 1997 March - August. The source was making a slow transition from a
low-hard state to a high-soft state in about three months and during this
transition it was exhibiting a series of fast variations which can be
classified as bursts. During one type of bursts, called the irregular bursts,
it was found that the source makes rapid transitions between two intensity
states. We have analyzed the RXTE PCA data obtained on 1997 June 18 (when the
source was making rapid state transitions) and compared the results with two
sets of data each pertaining to the low hard-state and high-soft states. We
find that the power density spectrum (PDS) during the burst shows remarkable
similarity to that seen during the high-soft state of the source. The PDS
during the quiescence, on the other hand, is quite flat and is very similar to
the PDS commonly seen during the canonical low-hard state of black hole X-ray
binaries. A low frequency QPO at $\sim$3 Hz is observed during the quiescence,
a property seen during the low-hard state of the source. The X-ray spectrum of
the source during quiescence is similar to the spectrum seen during the
low-hard state of the source and the spectra during the burst and high-soft
state are very similar to each other. These observations corroborate the
suggestion made by Yadav et al. (1999) that during the irregular bursts the
source shows spectral state variations at very fast time scales. We explain
such fast state changes using the two component accretion flow model in which
the accretion disk consists of a geometrically thin (and optically thick)
standard disk co-existing with an advection dominated hot thick disk.

</DOC>
<DOC>
<DOCNO> 68510 </DOCNO>
Light Hybrid Mesons in QCD


  Including the radiative perturbative corrections and the short distance
tachyonic gluon mass effects which mimic the ones of UV renormalons, we
re-estimate the decay amplitudes, masses and widths of light hybrid mesons from
QCD spectral sum rules. We show that the effects are tiny and confirm the
previous lowest order results. We discuss the phenomenological impacts of our
results for the vector hybrids.

</DOC>
<DOC>
<DOCNO> 101196 </DOCNO>
The Pseudospectral Properties of non-self-adjoint Schr\"odinger


  We describe the general qualitative behaviour of the resolvent norm for a
very wide class of non-self-adjoint Schroedinger operators in the
semi-classical regime, as the spectral parameter varies over the complex plane.

</DOC>
<DOC>
<DOCNO> 39842 </DOCNO>
The decay omega(782) -> 5 pi in chiral theory


  The arguments are put forward that the many pion decays omega ->2 pi^+ 2 pi^-
pi^0 and pi^+ pi^- 3 pi^0 provide an ideal test site for testing the
predictions of chiral models of the vector meson decays into many pions. Using
the approach based on the Weinberg Lagrangian or, in a new language, the
Lagrangian of hidden local symmetry added with the term induced by the
anomalous Lagrangian of Wess and Zumino, the partial widths of these decays are
evaluated, and their excitation curves in e^+e^- annihilation are obtained. The
discussed are the perspectives of the experimental study of the decays omega ->
5 pi in e^+e^- annihilation and photoproduction.

</DOC>
<DOC>
<DOCNO> 11161 </DOCNO>
Numerical study of surface-induced reorientation and smectic layering in


  Surface-induced profiles of both nematic and smectic order parameters in a
nematic liquid crystal, ranging from an orienting substrate to "infinity", were
evaluated numerically on base of an extended Landau theory. In order to obtain
a smooth behavior of the solutions at "infinity" a boundary energy functional
was derived by linearizing the Landau energy around its equilibrium solutions.
We find that the intrinsic wave number of the smectic structure, which plays
the role of a coupling between nematic and smectic order, strongly influences
the director reorientation. Whereas the smectic order is rapidly decaying when
moving away from the surface, the uniaxial nematic order parameter shows an
oscillatory behavior close to the substrate, accompanied by a non-zero local
biaxiality.

</DOC>
<DOC>
<DOCNO> 102268 </DOCNO>
Double Schubert polynomials and degeneracy loci for the classical groups


  Let $V$ be a vector bundle on an algebraic variety $X$ equipped with a
nondegenerate symplectic or orthogonal form. For each element $w$ in the
corresponding Weyl group there is a degeneracy locus $X_w$ defined using the
attitude of an isotropic flag $E_.$ with respect to a fixed complete isotropic
flag $F_.$ of subbundles of $V$. We define and study a family of 'double
Schubert polynomials' $P_w$ in the Chern roots of these bundles that represent
the class of $X_w$ in the Chow group $CH(X)$. We prove two main facts about
these polynomials: (i) when $w$ is a permutation in the symmetric group, $P_w$
has positive integer coefficients and is obtained by specializing a type $A$
double Schubert polynomial of Lascoux and Sch\"utzenberger; (ii) when $w$ is a
maximal Grassmannian element $P_w$ can be expressed in terms of Schur-type
determinants and Pfaffians, generalizing the formulas of Pragacz and Ratajski.
We also examine the question of extending (ii) to degeneracy loci of morphisms
of vector bundles satisfying isotropicity conditions, in analogy with the work
of Kempf and Laksov.

</DOC>
<DOC>
<DOCNO> 116351 </DOCNO>
Irreversibility and Measurement in Quantum Mechanics


  Irreversibility is often considered to characterize measurements in quantum
mechanics. Fundamental problems with this characterization are addressed.
First, whether a measurement is made in quantum mechanics is an arbitrary
decision on the part of the experimenter concerning how the experimental
circumstances are structured. Second, how is irreversibility that occurs in
making a measurement explained in terms of a neurophysiological mechanism where
a macroscopic measuring instrument is not required in principle to make the
measurement, as in macroscopic quantum tunneling? Third, how does
irreversibility characterize a negative observation where there is no physical
interaction in the measurement process?

</DOC>
<DOC>
<DOCNO> 69665 </DOCNO>
A Calculation of Higgs Mass in the Standard Model


  The assumption that the ratio of the Higgs self-coupling to the square of its
yukawa coupling to the top is (almost) independent of the renormalization scale
fixes the Higgs mass within narrow limits at m=160 GeV using only the values of
gauge couplings and top mass.

</DOC>
<DOC>
<DOCNO> 8077 </DOCNO>
Classes of behavior of small-world networks


  Small-world networks are the focus of recent interest because they appear to
circumvent many of the limitations of either random networks or regular
lattices as frameworks for the study of interaction networks of complex
systems. Here, we report an empirical study of the statistical properties of a
variety of diverse real-world networks. We present evidence of the occurrence
of three classes of small-world networks: (a) scale-free networks,
characterized by a vertex connectivity distribution that decays as a power law;
(b) broad-scale networks, characterized by a connectivity distribution that has
a power-law regime followed by a sharp cut-off; (c) single-scale networks,
characterized by a connectivity distribution with a fast decaying tail.
Moreover, we note for the classes of broad-scale and single-scale networks that
there are constraints limiting the addition of new links. Our results suggest
that the nature of such constraints may be the controlling factor for the
emergence of different classes of networks.

</DOC>
<DOC>
<DOCNO> 14155 </DOCNO>
Soft modes of collective domain-wall vibrations in epitaxial


  Mechanical restoring forces acting on ferroelastic domain walls displaced
from the equilibrium positions in epitaxial films are calculated for various
modes of their cooperative translational oscillations. For vibrations of the
domain-wall superlattice with the wave vectors corresponding to the center and
boundaries of the first Brillouin zone, the soft modes are singled out that are
distinguished by a minimum magnitude of the restoring force. It is shown that,
in polydomain ferroelectric thin films, the soft modes of wall vibrations may
create enormously large contribution to the film permittivity.

</DOC>
<DOC>
<DOCNO> 120040 </DOCNO>
Line Formation in the Atmosphere of Brown Dwarf Gliese 229B: $CH_4$ at


  We investigate the formation of methane line at 2.3 ${\rm \mu m}$ in Brown
Dwarf Gliese 229B. Two sets of model parameters with (a) $T_{\rm eff}=940 $K
and $\log (g) =5.0$, (b) $T_{\rm eff}=1030 $K and $ \log(g)=5.5$ are adopted
both of which provide excellent fit for the synthetic continuum spectra with
the observed flux at a wide range of wavelengths. In the absence of
observational data for individual molecular lines, we set the additional
parameters that are needed in order to model the individual lines by fitting
the calculated flux with the observed flux at the continuum. A significant
difference in the amount of flux at the core of the line is found with the two
different models although the flux at the ontinuum remains the same. Hence, we
show that if spectroscopic observation at $2.3{\rm \mu m}$ with a resolution as
high as $R \simeq 200,000$ is possible then a much better constraint on the
surface gravity and on the metallicity of the object could be obtained by
fitting the theoretical model of individual molecular line with the observed
data.

</DOC>
<DOC>
<DOCNO> 101588 </DOCNO>
An obstruction to conservation of volume in contact dynamics


  A theorem of Moser guarantees that every diffeomorphism of a closed manifold
can be isotoped to a volume preserving one. We show that this statement cannot
be extended into contact category: some connected components of
contactomorphism groups of certain contact manifolds contain no
volume-preserving diffeomorphisms. This phenomenon can be considered from
different viewpoints: geometric (isometric action of the contact mapping class
group on the moduli space of contact forms), topological (action in symplectic
homology) and dynamical (diffusion). We define a numerical invariant - a kind
of contact Lyapunov exponent - which leads to a quantitive version of the
abovementioned result.

</DOC>
<DOC>
<DOCNO> 119276 </DOCNO>
Photometric study of fields of nearby pulsars with the 6m telescope


  Fields of Geminga, PSR B0950+08, PSR J1908+0734 and PSR J0108-1431 have been
observed within the program of optical investigation of nearby neutron stars
carried out with the 6m telescope. Our multicolour BVR_cI_c photometry has
yielded the following magnitudes of Geminga: V=25.3+/-0.4; R_c=25.4+/-0.3. The
estimates of the 3\sigma upper limits in the B and I_c bands are 25.4 and 24.9,
respectively. This is in agreement with previous observations of Geminga. We
have suggested candidate for optical counterpart of PSR B0950+08, with
R_c=25.4+/-0.3. When compared to the HST data obtained in UV its flux shows
that this old pulsar can be brighter in near-IR than in near-UV. We have
obtained for the first time images of the fields of PSR J1908+0734 and PSR
J0108-1431. Although no optical counterparts have been detected, the magnutude
upper limits obtained suggest further observations of these pulsars.

</DOC>
<DOC>
<DOCNO> 71611 </DOCNO>
Spontaneous susy breaking in N=2 super Yang-Mills theories


  It is shown that the same essentially non-semiclassical mechanism, which
generates in the nonsupersymmetric pure Yang-Mills theory the binary condensate
of gauge field strengths, is responsible for the spontaneous breaking of the
two supersymmetries in N=2 super Yang-Mills systems. A detailed discussion is
presented in ref. \cite{LBPM}

</DOC>
<DOC>
<DOCNO> 69611 </DOCNO>
Noncyclic geometric phase for neutrino oscillation


  We provide explicit formulae for the noncyclic geometric phases or
Pancharatnam phases of neutrino oscillations. Since Pancharatnam phase is a
generalization of the Berry phase, our results generalize the previous findings
for Berry phase in a recent paper [Phys. Lett. B, 466 (1999) 262]. Unlike the
Berry phase, the noncyclic geometric phase offers distinctive advantage in
terms of measurement and prediction. In particular, for three-flavor mixing,
our explicit formula offers an alternative means of determining the
CP-violating phase. Our results can also be extended easily to explore
geometric phase associated with neutron-antineutron oscillations.

</DOC>
<DOC>
<DOCNO> 122562 </DOCNO>
Star Formation Histories of Nearby Dwarf Galaxies


  Properties of nearby dwarf galaxies are briefly discussed. Dwarf galaxies
vary widely in their star formation histories, the ages of their
subpopulations, and in their enrichment history. Furthermore, many dwarf
galaxies show evidence for spatial variations in their star formation history;
often in the form of very extended old populations and radial gradients in age
and metallicity. Determining factors in dwarf galaxy evolution appear to be
both galaxy mass and environment. We may be observing continuous evolution from
low-mass dwarf irregulars via transition types to dwarf spheroidals, whereas
other evolutionary transitions seem less likely.

</DOC>
<DOC>
<DOCNO> 118734 </DOCNO>
Increase of the pion-kaon Hawking radiation from Schwarzschild black


  An algorithm for numerical computation of the barrier transparency for the
potentials surrounding Schwarzschild black holes is described for massive
scalar particles. It is then applied to calculate the total (including all
particle species and the contributions of twisted field configurations
connected with Dirac monopoles) luminosity for the pion-kaon Hawking radiation
from a Schwarzschild black hole with mass $M=10^{12}$ g. It is found that the
contribution due to monopoles can be of order 11% of the total pion-kaon
luminosity.

</DOC>
<DOC>
<DOCNO> 84185 </DOCNO>
What Dimensions Do the Time and Space Have: Integer or Fractional?


  A theory of time and space with fractional dimensions (FD) of time and space
($d_{\alpha}, \alpha=t,{\bf r})$ defined on multifractal sets is proposed. The
FD is determined (using principle of minimum the functionals of FD) by the
energy densities of Lagrangians of known physical fields. To describe behaviour
of functions defined on multifractal sets the generalizations of the fractional
Riemann-Liouville derivatives $D_{t}^{d(t)}$ are introduced with the order of
differentiation (depending on time and coordinate) being equal the value of
fractional dimension. For $d_{t}=const$ the generalized fractional derivatives
(GFD) reduce to ordinary Riemann-Liouville integral functionals, and when
$d_{t}$ is close to integer, GFD can be represented by means of derivatives of
integer order. For time and space with fractional dimensions a method to
investigate the generalized equations of theoretical physics by means of GFD is
proposed. The Euler equations defined on multifractal sets of time and space
are obtained using the principle of the minimum of FD functionals. As an
example, a generalized Newton equation is considered and it is shown that this
equation coincide with the equation of classical limit of general theory of
relativity for $d_{t} \to 1$. Several remarks concerning existence of repulsive
gravitation are discussed. The possibility of geometrization all the known
physical fields and forces in the frames of the fractal theory of time and
space is demonstrated.

</DOC>
<DOC>
<DOCNO> 13734 </DOCNO>
Stripes Induced by Orbital Ordering in Layered Manganites


  Spin-charge-orbital ordered structures in doped layered manganites are
investigated using an orbital-degenerate double-exchange model tightly coupled
to Jahn-Teller distortions. In the ferromagnetic phase, unexpected diagonal
stripes at $x$=$1/m$ ($m$=integer) are observed, as in recent experiments.
These stripes are induced by the orbital degree of freedom, which forms a
staggered pattern in the background. A $\pi$-shift in the orbital order across
stripes is identified, analogous to the $\pi$-shift in spin order across
stripes in cuprates. At $x$=1/4 and 1/3, another non-magnetic phase with
diagonal static charge stripes is stabilized at intermediate values of the
$t_{\rm 2g}$-spins exchange coupling.

</DOC>
<DOC>
<DOCNO> 151523 </DOCNO>
T-duality of axial and vector dyonic integrable models


  A general construction of affine Non Abelian (NA) - Toda models in terms of
axial and vector gauged two loop WZNW model is discussed. They represent {\it
integrable perturbations} of the conformal $\sigma$-models (with tachyons
included) describing (charged) black hole type string backgrounds. We study the
{\it off-critical} T-duality between certain families of axial and vector type
of integrable models for the case of affine NA- Toda theories with one global
U(1) symmetry. In particular we find the Lie algebraic condition defining a
subclass of {\it T-selfdual} torsionless NA Toda models and their zero
curvature representation.

</DOC>
<DOC>
<DOCNO> 102807 </DOCNO>
Localic Galois Theory


  In Proposition I of "Memoire sur les conditions de resolubilite des equations
par radicaux", Galois established that any intermediate extension of the
splitting field of a polynomial with rational coefficients is the fixed field
of its galois group.
  We first state and prove the (dual) categorical interpretation of of this
statement, which is a theorem about atomic sites with a representable point. In
the general case, the point determines a proobject and it becomes
(tautologically) prorepresentable. We state and prove the, mutatus mutatis,
prorepresentable version of Galois theorem. In this case the classical group of
automorphisms has to be replaced by the localic group of automorphisms. These
developments form the content of a theory that we call "Localic Galois Theory".
  An straightforward corollary of this theory is the theorem: "A topos with a
point is connected atomic if and only if it is the classifying topos of a
localic group, and this group can be taken to be the locale of automorphisms of
the point". This theorem was first proved in print in Joyal A, Tierney M. "An
extension of the Galois Theory of Grothendieck", Mem. AMS 151, Theorem 1,
Section 3, Chapter VIII. Our proof is completely independent of descent theory
and of any other result in that paper.

</DOC>
<DOC>
<DOCNO> 170294 </DOCNO>
A sequence of unsharp measurements enabling a real time visualization of


  The normalized state $\ket{\psi(t)}=c_1(t)\ket{1}+c_2(t)\ket{2}$ of a single
two-level system performs oscillations under the influence of a resonant
driving field. It is assumed that only one realization of this process is
available. We show that it is possible to approximately visualize in real time
the evolution of the system as far as it is given by $|c_2(t)|^2$. For this
purpose we use a sequence of particular unsharp measurements separated in time.
They are specified within the theory of generalized measurements in which
observables are represented by positive operator valued measures (POVM). A
realization of the unsharp measurements may be obtained by coupling the
two-level system to a meter and performing the usual projection measurements on
the meter only.

</DOC>
<DOC>
<DOCNO> 12600 </DOCNO>
Nishimori point in the 2D +/- J random-bond Ising model


  We study the universality class of the Nishimori point in the 2D +/- J
random-bond Ising model by means of the numerical transfer-matrix method. Using
the domain-wall free-energy, we locate the position of the fixed point along
the Nishimori line at the critical concentration value p_c = 0.1094 +/- 0.0002
and estimate nu = 1.33 +/- 0.03. Then, we obtain the exponents for the moments
of the spin-spin correlation functions as well as the value for the central
charge c = 0.464 +/- 0.004. The main qualitative result is the fact that
percolation is now excluded as a candidate for describing the universality
class of this fixed point.

</DOC>
<DOC>
<DOCNO> 10392 </DOCNO>
The Spin Excitation Spectrum in Superconducting ${\bf


  A comprehensive inelastic neutron scattering study of magnetic excitations in
the near-optimally doped high-temperature superconductor ${\rm
YBa_{2}Cu_{3}O_{6.85}}$ is presented. The spin correlations in the normal state
are commensurate with the crystal lattice, and the intensity is peaked around
the wave vector characterizing the antiferromagnetic state of the insulating
precursor ${\rm YBa_{2}Cu_{3}O_{6}}$. Profound modifications of the spin
excitation spectrum appear abruptly below the superconducting transition
temperature, $\rm T_C$, where a commensurate resonant mode and a set of weaker
incommensurate peaks develop. The data are consistent with models based on an
underlying two-dimensional Fermi surface that predict a continuous, downward
dispersion relation connecting the resonant mode and the incommensurate
excitations. The magnetic incommensurability in the ${\rm
YBa_{2}Cu_{3}O_{6+x}}$ system is thus not simply related to that of another
high temperature superconductor, ${\rm La_{2-x}Sr_xCuO_{4}}$, where
incommensurate peaks persist well above $\rm T_C$. The temperature dependent
incommensurability is difficult to reconcile with interpretations based on
charge stripe formation in ${\rm YBa_{2}Cu_{3}O_{6+x}}$ near optimum doping.

</DOC>
<DOC>
<DOCNO> 122596 </DOCNO>
Extremely red galaxy counterparts to 7C radio sources


  We present RIJHK imaging of seven radio galaxies from the 7C Redshift Survey
(7CRS) which lack strong emission lines and we use these data to investigate
their spectral energy distributions (SEDs) with models which constrain their
redshifts. Six of these seven galaxies have extremely red colours (R-K>5.5) and
we find that almost all of them lie in the redshift range 1<z<2. We also
present near-infrared spectroscopy of these galaxies which demonstrate that
their SEDs are not dominated by emission lines, although tentative lines,
consistent with H-alpha at z=1.45 and z=1.61, are found in two objects.
Although the red colours of the 7CRS galaxies can formally be explained by
stellar populations which are either very old or young and heavily reddened,
independent evidence favours the former hypothesis. At z~1.5 at least 1/4 of
powerful radio jets are triggered in massive (>L*) galaxies which formed the
bulk of their stars several Gyr earlier, that is at epochs corresponding to
redshifts z>5. If a similar fraction of all z~1.5 radio galaxies are old, then
extrapolation of the radio luminosity function shows that, depending on the
radio source lifetimes, between 10-100% of the near-IR selected extremely red
object (ERO) population undergo a radio outburst at epochs corresponding to
1<z<2. An ERO found serendipitously in the field of one of the 7CRS radio
sources appears to be a radio-quiet analogue of the 7CRS EROs with an emission
line likely to be [OII] at z=1.20. The implication is that some of the most
massive elliptical galaxies formed the bulk of their stars at z>5 and these
objects probably undergo at least two periods of AGN activity: one at high
redshift during which the black hole forms and another one at an epoch
corresponding to z~1.5.

</DOC>
<DOC>
<DOCNO> 99573 </DOCNO>
Almost ring theory


  The categories of almost modules and almost algebras are introduced as a
convenient setting for the development of Faltings' method of almost etale
extensions. After some preliminaries of general "almost homological algebra" we
construct the almost version of the cotangent complex and we use it to
generalise some results of Faltings on the lifting of almost etale morphisms
and almost etale algebras over nilpotent extensions. We also study the "almost
trace" of an almost flat and almost finitely presented morphism, in particular
we show that the almost trace is (almost) perfect if and only if the morphism
is almost etale. Finally we study some cases of non-flat descent for almost
rings, and establish the invariance of almost etale morphisms under Frobenius.

</DOC>
<DOC>
<DOCNO> 40666 </DOCNO>
Analysis of B-> \phi K Decays in QCD Factorization


  We analyze the decay $B\to \phi K$ within the framework of QCD-improved
factorization. We found that although the twist-3 kaon distribution amplitude
dominates the spectator interactions, it will suppress the decay rates
slightly. The weak annihilation diagrams induced by $(S-P)(S+P)$ penguin
operators, which are formally power-suppressed by order $(\Lambda/m_b)^2$, are
chirally and logarithmically enhanced. Therefore, these annihilation
contributions are not subject to helicity suppression and can be sizable. The
predicted branching ratio of $B^-\to\phi K^-$ is $(3.8\pm0.6)\times 10^{-6}$ in
the absence of annihilation contributions and it becomes
$(4.3^{+3.0}_{-1.4})\times 10^{-6}$ when annihilation effects are taken into
account. The prediction is consistent with CLEO and BaBar data but smaller than
the BELLE result.

</DOC>
<DOC>
<DOCNO> 85019 </DOCNO>
On a model of an unconstrained hyperfluid


  A hyperfluid is a classical continuous medium carrying hypermomentum. We
modify the earlier developed variational approach to a hyperfluid in such a way
that the Frenkel type constraints imposed on the hypermomentum current are
eliminated. The resulting self-consistent model is different from the
Weyssenhoff type one. The essential point is a conservation of the
hypermomentum current such that the final metrical and canonical
energy-momentum forms coincide.

</DOC>
<DOC>
<DOCNO> 178689 </DOCNO>
The Love-Hate Relationship Between the Shell Model and Cluster Models


  We adopt a personal approach here reviewing several calculations over the
years in which we have experienced confrontations between cluster models and
the shell model. In previous cluster conferences we have noted that cluster
models go hand in hand with Skyrme Hartee-Fock calculations in describing
states which cannot easily, if at all, be handled by the shell model. These are
the highly deformed (many particle - many hole) intruder states, linear chain
states e.t.c. In the present work we will consider several topics; the
quadrupole moment of $^{6}$Li, the non-existence of low lying intruders in
$^{8}$Be, and then jumping to the $f_{7/2}$ shell, we discuss the two-faceted
nature of the nuclei - sometimes displaying shell model properties, other times
cluster properties.

</DOC>
<DOC>
<DOCNO> 84418 </DOCNO>
Massive Scalar Particles in a Modified Schwarzschild Geometry


  Massive, spinless bosons have vanishing probability of reaching the sphere
r=2M from the region r>2M when the original Schwarzschild metric is modified by
maximal acceleration corrections.

</DOC>
<DOC>
<DOCNO> 120205 </DOCNO>
Characterizing the non-linear growth of large-scale structure in the


  The local Universe displays a rich hierarchical pattern of galaxy clusters
and superclusters. The early Universe, however, was almost smooth, with only
slight 'ripples' seen in the cosmic microwave background radiation. Models of
the evolution of structure link these observations through the effect of
gravity, because the small initially overdense fluctuations attract additional
mass as the Universe expands. During the early stages, the ripples evolve
independently, like linear waves on the surface of deep water. As the
structures grow in mass, they interact with other in non-linear ways, more like
waves breaking in shallow water. We have recently shown how cosmic structure
can be characterized by phase correlations associated with these non-linear
interactions, but hitherto there was no way to use that information to reach
quantitative insights into the growth of structures. Here we report a method of
revealing phase information, and quantify how this relates to the formation of
a filaments, sheets and clusters of galaxies by non-linear collapse. We use a
new statistic based on information entropy to separate linear from non-linear
effects and thereby are able to disentangle those aspects of galaxy clustering
that arise from initial conditions (the ripples) from the subsequent dynamical
evolution.

</DOC>
<DOC>
<DOCNO> 122303 </DOCNO>
What can we infer about the underlying physics from burst distributions


  We determine that the sizes of bursts in mean-square current density in a
reduced magnetohydrodynamic (RMHD)simulation follow power-law probability
density function (PDF). The PDFs for burst durations and waiting time between
bursts are clearly not exponential and could also be power-law. This suffices
to distinguish their behaviour from the original Bak et al. sandpile model
which had exponential waiting time PDFs. However, it is not sufficient to
distinguish between turbulence, some other SOC-like models, and other red noise
sources.

</DOC>
<DOC>
<DOCNO> 152113 </DOCNO>
Recurrent dynamical symmetry breaking and restoration by Wilson lines at


  In this paper we derive the general expression of a one-loop effective
potential of the nonintegrable phases of Wilson lines for an SU(N) gauge theory
with a massless adjoint fermion defined on the spactime manifold
$R^{1,d-3}\times T^2$ at finite temperature and fermion density. The Phase
structure of the vacuum is presented for the case with $d=4$ and N=2 at zero
temperature. It is found that gauge symmetry is broken and restored alternately
as the fermion density increases, a feature not found in the Higgs mechanism.
It is the manifestation of the quantum effects of the nonintegrable phases.

</DOC>
<DOC>
<DOCNO> 121798 </DOCNO>
Wide Field Imaging of the Hubble Deep Field South Region II: The


  We present the galaxy-galaxy angular correlations as a function of
photometric redshift in a deep-wide galaxy survey centered on the Hubble Deep
Field South. Images were obtained with the Big Throughput Camera on the Blanco
4m telescope at CTIO, of 1/2 square degree in broad-band uBVRI, reaching ~24th
mag. Approximately 40,000 galaxies are detected in the survey. We determine
photometric redshifts using galaxy template fitting to the photometry. Monte
Carlo simulations show that redshifts from these data should be reliable out to
z~1, where the 4000 Angstrom break shifts into the I-band. The inferred
redshift distribution, n(z), shows good agreement with the distribution of
galaxies measured in the HDF North and the Canada-France Redshift Survey. After
assigning galaxies to redshift bins with width Delta_z=0.33, we determine the
two point angular correlation function in each bin. We find that the amplitude
of the correlation, A_w, drops across the three bins to redshift z~1. Simple
epsilon models of clustering evolution fit this result, with the best agreement
for epsilon=0. Hierarchical cold-dark-matter models best fit in a low density,
Lambda-dominated universe.

</DOC>
<DOC>
<DOCNO> 122161 </DOCNO>
Variability of eta Carinae III


  Spectra (1951-78) of the central object in eta Car, taken by A.D. Thackeray,
reveal three previously unrecorded epochs of low excitation. Since 1948, at
least, these states have occurred regularly in the 2020 day cycle proposed by
Damineli et al. They last about 10 percent of each cycle. Early slit spectra
(1899-1919) suggest that at that time the object was always in a low state.
JHKL photometry is reported for the period 1994-2000. This shows that the
secular increase in brightness found in 1972-94 has continued and its rate has
increased at the shorter wavelengths. Modulation of the infrared brightness in
a period near 2020 days continues. There is a dip in the JHKL light curves near
1998.0, coincident with a dip in the X-ray light curve. Evidence is given that
this dip in the infrared repeats in the 2020 day cycle. As suggested by
Whitelock & Laney, the dip is best interpreted as an eclipse phenomenon in an
interacting binary system; the object eclipsed being a bright region (`hot
spot'), possibly on a circumstellar disc or produced by interacting stellar
winds. The eclipse coincides in phase and duration with the state of low
excitation. It is presumably caused by a plasma column and/or by one of the
stars in the system.

</DOC>
<DOC>
<DOCNO> 67861 </DOCNO>
Anomaly mediated SUSY breaking at the LHC


  Anomaly Mediated SUSY Breaking models are reviewed. Possible signatures at
the LHC for one case of the minimal realistic model are examined.

</DOC>
<DOC>
<DOCNO> 100192 </DOCNO>
Ample Divisors, Automorphic Forms and Shafarevich's Conjecture


  In this article we give a general approach to the following analogue of
Shafarevich's conjecture for some polarized algebraic varieties; suppose that
we fix a type of an algebraic variety and look at families of such type of
varieties over a fixed Riemann surface with fixed points over which we have
singular varieties, then one can ask if the set of such families, up to
isomorphism, is finite.
  In this paper we give a general approach to such types of problems. The main
observation is the following; suppose that the moduli space of a fixed type of
algebraic polarized variety exists and suppose that in some projective smooth
compactification of the coarse moduli the discriminant divisor supports an
ample one, then it is not difficult to see that this fact implies the analogue
of Shafarevich's conjecture.
  In this article we apply this method to certain polarized algebraic K3
surfaces and also to Enriques surfaces.

</DOC>
<DOC>
<DOCNO> 8577 </DOCNO>
On global existence of localized solutions of some nonlinear lattices


  We prove global existence and uniqueness of solutions of some important
nonlinear lattices which include the Fermi-Pasta-Ulam (FPU) lattice. Our result
shows (on a particular example) that the FPU lattice with high nonlinearity and
its continuum limit display drastically different behaviour with respect to
blow up phenomenon.

</DOC>
<DOC>
<DOCNO> 39735 </DOCNO>
Measurement of omega meson parameters in pi^+pi^-pi^0 decay mode with


  About 11 200 e^+e^- -> omega -> pi^+pi^-pi^0 events selected in the center of
mass energy range from 760 to 810 MeV were used for the measurement of the
\omega meson parameters. The following results have been obtained: sigma
_{0}=(1457 \pm 23 \pm 19)nb, m_{\omega}=(782.71 \pm 0.07 \pm 0.04) MeV/c^{2},
  \Gamma_{\omega}=(8.68 \pm 0.23 \pm 0.10) MeV,
  \Gamma_{e^+e^-}\cdot Br (\omega -> pi^+pi^-pi^0)=
  (0.528 \pm 0.012 \pm 0.007) \cdot 10^{-3} MeV.

</DOC>
<DOC>
<DOCNO> 100606 </DOCNO>
Three-Manifold Invariants from Chern-Simons Field Theory with Arbitrary


  Invariants for framed links in $S^3$ obtained from Chern-Simons gauge field
theory based on an arbitrary gauge group (semi-simple) have been used to
construct a three-manifold invariant. This is a generalization of a similar
construction developed earlier for SU(2) Chern-Simons theory. The procedure
exploits a theorem of Lickorish and Wallace and also those of Kirby, Fenn and
Rourke which relate three-manifolds to surgeries on framed unoriented links.
The invariant is an appropriate linear combination of framed link invariants
which does not change under Kirby calculus. This combination does not see the
relative orientation of the component knots. The invariant is related to the
partition function of Chern-Simons theory. This thus provides an efficient
method of evaluating the partition function for these field theories. As some
examples, explicit computations of these manifold invariants for a few
three-manifolds have been done.

</DOC>
<DOC>
<DOCNO> 71645 </DOCNO>
Longitudinal, transverse-plus and transverse-minus W-bosons in


  We consider the O(alpha_s) radiative corrections to the decay of an
unpolarized top quark into a bottom quark and a W-gauge boson where the
helicities of the W are specified as longitudinal, transverse-plus and
transverse-minus. The O(alpha_s) radiative corrections lower the normalized
longitudinal rate Gamma_L/Gamma by 1.06% and increase the the normalized
transverse-minus rate Gamma_-/Gamma by 2.17%. We find that the normalized
transverse-plus rate Gamma_+/Gamma, which vanishes at the Born term level for
m_b->0, receives radiative correction contributions at the sub-percent level.
We discuss m_b!=0 effects for the Born term and the alpha_s-contributions but
find these to be small. Our results are discussed in the light of recent
measurements of the helicity content of the W in top quark decays by the CDF
Collaboration.

</DOC>
<DOC>
<DOCNO> 13131 </DOCNO>
Frictional drag between non-equilibrium charged gases


  The frictional drag force between separated but coupled two-dimensional
electron gases of different temperatures is studied using the non-equilibrium
Green function method based on the separation of center-of-mass and relative
dynamics of electrons. As the mechanisms of producing the frictional force we
include the direct Coulomb interaction, the interaction mediated via virtual
and real TA and LA phonons, optic phonons, plasmons, and TA and LA
phonon-electron collective modes. We found that, when the distance between the
two electron gases is large, and at intermediate temperature where plasmons and
collective modes play the most important role in the frictional drag, the
possibility of having a temperature difference between two subsystems modifies
greatly the transresistivity.

</DOC>
<DOC>
<DOCNO> 12754 </DOCNO>
Recurrent oligomers in proteins - an optimal scheme reconciling accurate


  A novel scheme is introduced to capture the spatial correlations of
consecutive amino acids in naturally occurring proteins. This knowledge-based
strategy is able to carry out optimally automated subdivisions of protein
fragments into classes of similarity. The goal is to provide the minimal set of
protein oligomers (termed ``oligons'' for brevity) that is able to represent
any other fragment. At variance with previous studies where recurrent local
motifs were classified, our concern is to provide simplified protein
representations that have been optimised for use in automated folding and/or
design attempts. In such contexts it is paramount to limit the number of
degrees of freedom per amino acid without incurring in loss of accuracy of
structural representations. The suggested method finds, by construction, the
optimal compromise between these needs. Several possible oligon lengths are
considered. It is shown that meaningful classifications cannot be done for
lengths greater than 6 or smaller than 4. Different contexts are considered
were oligons of length 5 or 6 are recommendable. With only a few dozen of
oligons of such length, virtually any protein can be reproduced within typical
experimental uncertainties. Structural data for the oligons is made publicly
available.

</DOC>
<DOC>
<DOCNO> 39638 </DOCNO>
Performance of the NuTeV Fe-Scintillator Sampling Calorimeter and


  NuTeV is a neutrino-nucleon deep inelastic scattering experiment at Fermilab.
The NuTeV detector is a traditional heavy target neutrino detector which
consists of an iron/liquid scintillator sampling calorimeter followed by a muon
spectrometer. The calorimeter response to hadrons, muons and electrons has been
measured in an in situ calibration beam over the energy range from 4.5 to 190
GeV. The small non-linearity of the response to hadrons is compared to the
expectation from the measured ratio of responses between electrons and hadrons
combined with the energy dependence of the fractional electromagnetic energy
deposition in the form of neutral pions in hadronic showers
$f_{\pi^{0}}(E_{\pi})$. The predictions use $f_{\pi^{0}}(E_{\pi})$ from the
Monte Carlo simulations by GHEISHA, GFLUKA and GCALOR and also from the
parameterizations of Wigmans and Groom. In addition, a study based on the NuTeV
hadron calibration data of the effectiveness of a thin calorimeter is
presented. The results of this study have important consequences for the energy
resolution of calorimeters used in other applications; for example, measuring
the cosmic ray flux in space or with balloon-based experiments.

</DOC>
<DOC>
<DOCNO> 84717 </DOCNO>
Modified Black Hole with Polar Jet and Vortex


  There are many models relating an accretion disk of Black Hole to jet
outflow. The herein heuristic model describes the continuation of an external
accretion disk to an internal accretion disk for less than Black Hole horizon,
and subsequent polar jet outflow along polar axis out of polar vortex wherein
the event horizon is no longer descriptive.

</DOC>
<DOC>
<DOCNO> 10646 </DOCNO>
A survey of nonadiabatic superconductivity in cuprates and fullerides


  High-$T_c$ superconductors are characterized by very low carrier densities.
This feature leads to two fundamental consequences: on one hand the Fermi
energies are correspondingly small and they can be of the same order of phonon
frequencies. In such a situation nonadiabatic corrections arising from the
breakdown of Migdal's theorem can not be longer neglected. In addition, small
carrier densities imply poor screening and correlation effects have to be taken
into account. We present a comprehensive overview of the theory of
superconductivity generalized into the nonadiabatic regime which is
qualitatively different from the conventional one. In this framework some of
the observed properties of the cuprates and the fullerene compounds can be
naturally accounted for, and a number of theoretical predictions are proposed
that can be experimentally tested.

</DOC>
<DOC>
<DOCNO> 10474 </DOCNO>
Time-temperature superposition in viscous liquids


  Dielectric relaxation measurements on supercooled triphenyl phosphite show
that at low temperatures time-temperature superposition (TTS) is accurately
obeyed for the primary (alpha) relaxation process. Measurements on 6 other
molecular liquids close to the calorimetric glass transition indicate that TTS
is linked to an $\omega^{-1/2}$ high-frequency decay of the alpha loss, while
the loss peak width is nonuniversal.

</DOC>
<DOC>
<DOCNO> 121181 </DOCNO>
On Black Hole Masses and Radio Loudness in AGN


  The distribution of radio to optical fluxes in AGN is bimodal. The physical
origin for this bimodality is not understood. In this Letter I describe
observational evidence, based on the Boroson & Green PG quasar sample, that the
radio loudness bimodality is strongly related to the black hole mass (M_BH).
Nearly all PG quasars with M_BH>10^9M_sun are radio loud, while quasars with
M_BH<3x10^8M_sun are practically all radio quiet. This result is consistent
with the dependence of quasar host galaxy morphology on radio loudness. There
is no simple physical explanation for this result, but it may provide a clue on
how jets are formed near massive black holes. The radio loudness--black hole
mass relationship suggests that the properties of various types of AGN may be
largely set by three basic parameters, M_BH, L/L_Eddington, and inclination
angle.

</DOC>
<DOC>
<DOCNO> 116907 </DOCNO>
A Highly Flexible Bunch Compressor for the APS LEUTL FEL


  The LEUTL FEL at the APS has achieved gain at 530 nm with peak beam current
\~100 A. In an effort to push to 120 nm and beyond, we have designed and are
commissioning a bunch compressor to increase the peak current to 600 A or more.
The bunch compressor uses a four-dipole chicane at an energy of 100 to 210 MeV.
To provide options for control of emittance growth due to coherent synchrotron
radiation (CSR), the chicane has variable R56. The central pair of dipoles is
movable, accommodating variable R56 with less concern about emittance dilution
from nonuniformity of the dipole field. The symmetry of the chicane is also
variable via longitudinal motion of the final dipole, which is predicted to
have an effect on emittance growth. Following the chicane, a three-screen
emittance measurement system should permit resolution of the difference in
emittance growth between various chicane configurations. A vertical bending
magnet analysis line is present to permit imaging of correlations between
transverse and energy coordinates. This paper reviews the features and expected
performance of the chicane. A companion paper discusses the physics design in
detail.
  Work supported by the U.S. Department of Energy, Office of Basic Energy
Sciences, under Contract No. W-31-109-ENG-38.

</DOC>
<DOC>
<DOCNO> 11260 </DOCNO>
Dimerization of Ferrimagnets on Chains and Square Lattices


  A linear spin wave analysis of dimerization of alternating Heisenberg system
with spins $s_{1}$ and $s_{2}$ on linear chain as well as square lattice is
presented. Among the several possible dimerized configurations considered in
two dimensions the plaquette configuration is found to be energetically the
most favored one. Inclusion of a variable nearest neighbor exchange coupling
$J(a)=\frac{J}{a}$ leads to a uniform power law behavior: that is to say, the
same $\delta $-dependence is found (i) in chains as well as in square lattices;
(ii) in systems consisting of different pairs of spins $s_{1}$ and $s_{2}$;
(iii) for the magnetic energy gain, the energy gap, the energy of the gapped
magnetic excitation mode as well as for the sublattice magnetization; (iv) for
all the configurations of the square lattice; and (v) in the entire range of
$\delta :$ $(0\leq \delta <1)$. The variable exchange coupling also allows \
the energy of the gapped excitation spectrum to be $\delta $-dependent even in
the linear spin wave theory.

</DOC>
<DOC>
<DOCNO> 9269 </DOCNO>
Field Driven Pairing State Phase Transition in d_x^2-y^2+id_xy-Wave


  Within the framework of the Ginzburg-Landau theory for
$d_{x^2-y^2}+id_{xy}$-wave superconductors, we discuss the pairing state phase
transition in the absence of the Zeeman coupling between the Cooper pair
orbital angular momentum and the magnetic field. We find that above a
temperature $T_{\ast}$, the pairing state in a magnetic field is pure
$d_{x^{2}-y^{2}}$-wave. However, below $T_{\ast}$, the pairing state is
$d_{x^{2}-y^{2}}+id_{xy}$-wave at low fields, and it becomes pure
$d_{x^{2}-y^{2}}$-wave at higher fields. Between these pairing states there
exists a field driven phase transition . The transition field increases with
decreasing temperature. In the field-temperature phase diagram, the phase
transition line is obtained theoretically by a combined use of a variational
method and the Virial theorem. The analytical result is found to be in good
agreement with numerical simulation results of the Gingzburg-Landau equations.
The validity of the variational method is discussed. The difference to the case
with the Zeeman coupling is discussed, which may be utilized to the detection
of the Zeeman coupling.

</DOC>
<DOC>
<DOCNO> 69008 </DOCNO>
Elastic pp and $\bar pp$ scattering in the Modified Additive Quark Model


  The modified additive quark model, proposed recently, allows to improve
agreement of the standard additive quark model with the data on the $pp, \bar
pp, \pi^{\pm} p, \gamma p$ and $\gamma \gamma$ total cross-sections, as well as
on the ratios of real to imaginary part of $pp$ and $\bar pp$ amplitudes at
$t=0$. Here, we extend this model to non forward elastic scattering of protons
and antiprotons. A high quality reproduction of angular distributions at 19.4
GeV $\leq \sqrt{s}\leq $ 1800 Gev is obtained. A zero at small $|t|$ in the
real part of even amplitude in accordance with a recently proved high energy
general theorem is found.

</DOC>
<DOC>
<DOCNO> 85459 </DOCNO>
Kruskal coordinates as canonical variables for Schwarzschild black holes


  We derive a transformation from the usual ADM metric-extrinsic curvature
variables on the phase space of Schwarzschild black holes, to new canonical
variables which have the interpretation of Kruskal coordinates. We explicitly
show that this transformation is non-singular, even at the horizon. The
constraints of the theory simplify in terms of the new canonical variables and
are equivalent to the vanishing of the canonical momenta. Our work is based on
earlier seminal work by Kuchar in which he reconstructed curvature coordinates
and a mass function from spherically symmetric canonical data. The key feature
in our construction of a nonsingular canonical transformation to Kruskal
variables, is the scaling of the curvature coordinate variables by the mass
function rather than by the mass at left spatial infinity.

</DOC>
<DOC>
<DOCNO> 70956 </DOCNO>
Resonant dynamics within the nonlinear Klein-Gordon Equation: Much ado


  This dissertation discusses solutions to the nonlinear Klein-Gordon equation
with symmetric and asymmetric double-well potentials, focusing on the collapse
and collision of bubbles and critical phenomena found therein. A new method is
presented that allows the solution of massive field equations on a (relatively)
small static grid. A coordinate transformation is used that transforms typical
flatspace coordnates to coordinates that move outward (near the outer boundary)
at nearly the speed of light. The outgoing radiation is compressed to nearly
the Nyquist limit of the grid where it is quenched by dissipation. The method
is implemented successfully in both spherically symmetric and axisymmetric
codes. New resonant oscillon solutions are discussed and the threshold of
expanding bubble formation is explored in both spherical and axial symmetry.
Approximate resonant oscillon solutions are obtained using trial function
methods and variational principles that are consistent with dynamical
evolutions.

</DOC>
<DOC>
<DOCNO> 69125 </DOCNO>
Phenomenology of transverse single spin asymmetries in inclusive


  A phenomenological description of single transverse spin asymmetries for the
inclusive production of hadrons in proton-proton and lepton-proton processes is
discussed within pQCD and a straightforward generalization of the factorization
theorem with the inclusion of parton intrinsic transverse motion. Fits to
existing data, predictions for new processes and interpretation of recent
results are presented.

</DOC>
<DOC>
<DOCNO> 85158 </DOCNO>
Notes on Isolated Horizons


  A general analysis for characterizing and classifying `isolated horizons' is
presented in terms of null tetrads and spin coefficients. The freely
specifiable spin coefficients corresponding to isolated horizons are identified
and specific symmetry classes are enumerated. For isolated horizons admitting
at least one spatial isometry, a standard set of spherical coordinates are
introduced and associated metric is obtained. An angular momentum is also
defined.

</DOC>
<DOC>
<DOCNO> 12133 </DOCNO>
Spin-phonon coupled modes in the incommensurate phases of doped


  The doping effect of the folded phonon mode at 98 cm$^{-1}$ was investigated
on the Si-doped CuGeO$_3$ by magneto-optical measurements in far-infrared (FIR)
region under high magnetic field. The folded phonon mode at 98 cm$^{-1}$
appears not only in the dimerized (D) phase but also in the
dimerized-anitiferromagnetic (DAF) phase on the doped CuGeO$_3$. The splitting
was observed in the incommensurate (IC) phase and the antiferromagnetically
ordered incommensurate (IAF) phase above $H_C$. The split-off branches exhibit
different field dependence from that of the pure CuGeO$_3$ in the vicinity of
$H_C$, and the discrepancy in the IAF phase is larger than that in the IC
phase. It is caused by the interaction between the solitons and the impurities.

</DOC>
<DOC>
<DOCNO> 83364 </DOCNO>
Temporal Expressions in Japanese-to-English Machine Translation


  This paper describes in outline a method for translating Japanese temporal
expressions into English. We argue that temporal expressions form a special
subset of language that is best handled as a special module in machine
translation. The paper deals with problems of lexical idiosyncrasy as well as
the choice of articles and prepositions within temporal expressions. In
addition temporal expressions are considered as parts of larger structures, and
the question of whether to translate them as noun phrases or adverbials is
addressed.

</DOC>
<DOC>
<DOCNO> 100823 </DOCNO>
DGBV Algebras and Mirror Symmetry


  We describe some recent development on the theory of formal Frobenius
manifolds via a construction from differential Gerstenhaber-Batalin-Vilkovisk
(DGBV) algebras and formulate a version of mirror symmetry conjecture: the
extended deformation problems of the complex structure and the Poisson
structure are described by two DGBV algebras; mirror symmetry is interpreted in
term of the invariance of the formal Frobenius manifold structures under
quasi-isomorphism.

</DOC>
<DOC>
<DOCNO> 120443 </DOCNO>
The GHz-Peaked Spectrum radio galaxy 2021+614: Detection of slow motion


  We have analysed VSOP (VLBI Space Observatory Programme) data at 5 GHz and
ground-based VLBI (Very Long Baseline Interferometry) data at 15 GHz for the
GHz-Peaked Spectrum (GPS) radio galaxy 2021+614. Its morphology is consistent
with it being a compact symmetric source extending over 30 h^-1 pc (H_0 = 100 h
km s^-1 Mpc^-1, q_0 = 0.5). From a comparison with earlier observations we have
detected an increase in the separation and a decrease in the size of the two
most prominent components. We determine the projected speed with which these
two components recede from each other to be 0.12+/-0.02 h^-1 c. Given the
projected separation of the two components of 16.1 h^-1 pc, the infered
kinematic age is 440+/-80 years, measured in the source reference frame. These
results provide additional support for the contention that compact symmetric
radio objects are young and the precursors of the classical FR I or FR II radio
sources. The sizes of individual components appear to contract with time which
is not consistent with the self-similar evolution model for peaked spectrum
sources.
  In order to overcome problems related to the estimation of uncertainties for
separation measurements between source components, we have developed and
applied a method that compares two uv-data sets obtained at different epochs.
This method parametrizes the most important structural change, the increase in
separation between components, by rescaling the u and v axis of the amplitude
interference pattern. It provides best-fit values for the parameters and uses a
bootstrap method to estimate the errors in the parameters.

</DOC>
<DOC>
<DOCNO> 10754 </DOCNO>
Dimensionality effects in restricted bosonic and fermionic systems


  The phenomenon of Bose-like condensation, the continuous change of the
dimensionality of the particle distribution as a consequence of freezing out of
one or more degrees of freedom in the low particle density limit, is
investigated theoretically in the case of closed systems of massive bosons and
fermions, described by general single-particle hamiltonians. This phenomenon is
similar for both types of particles and, for some energy spectra, exhibits
features specific to multiple-step Bose-Einstein condensation, for instance the
appearance of maxima in the specific heat.
  In the case of fermions, as the particle density increases, another
phenomenon is also observed. For certain types of single particle hamiltonians,
the specific heat is approaching asymptotically a divergent behavior at zero
temperature, as the Fermi energy $\epsilon_{\rm F}$ is converging towards any
value from an infinite discrete set of energies: ${\epsilon_i}_{i\ge 1}$. If
$\epsilon_{\rm F}=\epsilon_i$, for any i, the specific heat is divergent at T=0
just in infinite systems, whereas for any finite system the specific heat
approaches zero at low enough temperatures. The results are particularized for
particles trapped inside parallelepipedic boxes and harmonic potentials.
  PACS numbers: 05.30.Ch, 64.90.+b, 05.30.Fk, 05.30.Jp

</DOC>
<DOC>
<DOCNO> 122174 </DOCNO>
Cassiopeia A: on the origin of the hard X-ray continuum and the


  We present the first results on the hard X-ray continuum image (up to 15 keV)
of the supernova remnant Cas A measured with the EPIC cameras onboard
XMM-Newton. The data indicate that the hard X-ray tail, observed previously,
that extends to energies above 100 keV does not originate in localised regions,
like the bright X-ray knots and filaments or the primary blast wave, but is
spread over the whole remnant with a rather flat hardness ratio of the 8-10 and
10-15 keV energy bands. This result does not support an interpretation of the
hard X-radiation as synchrotron emission produced in the primary shock, in
which case a limb brightened shell of hard X-ray emission close to the primary
shock front is expected. In fact a weak rim of emission near the primary shock
front is discernable in the hardest X-ray image but it contains only a few
percent of the hard X-ray emissivity. The equivalent width of the Fe-K line
blend varies by more than an order of magnitude over the remnant, it is hard to
explain this as Fe-emission from the reverse shock heated ejecta given the
ejecta temperature and the age of the remnant. The uniquely high
wavelength-dispersive RGS-spectrometer has allowed, for the first time, to
extract monochromatic images in several highly ionised element species with
high spectral resolution. We present here a preliminary result on the
measurement of the O VIII Ly-alpha and Ly-beta brightness distribution and
brightness ratios. The large observed decrease of the Ly-alpha/Ly-beta ratio
going from the N to the SE can be explained by small-scale (10 arcsec)
variations in the N_H column over the remnant and the potential presence of
resonance scattering of the O VIII Ly-alpha photons in the limb brightened
shell.

</DOC>
<DOC>
<DOCNO> 150367 </DOCNO>
The Tachyon Potential in Open Neveu-Schwarz String Field Theory


  A classical action for open superstring field theory has been proposed which
does not suffer from contact term problems. After generalizing this action to
include the non-GSO projected states of the Neveu-Schwarz string, the pure
tachyon contribution to the tachyon potential is explicitly computed. The
potential has a minimum of $V = -{1\over{32 g^2}}$ which is 60% of the
predicted exact minimum of $V=-{1\over{2\pi^2 g^2}}$ from D-brane arguments.

</DOC>
<DOC>
<DOCNO> 68216 </DOCNO>
A comment on baryogenesis at the electroweak scale in alternative


  In this study we examine post-inflationary cosmologies dominated by a scalar
field with the equation of state: p_phi=w_phi rho_phi (0 leq w_phi leq 1) in
order to facilitate baryogenesis at the electroweak scale. We take a more
conventional approach from one in Ref. 1 [Joyce, Prokopec] and assume that the
Universe reheats by the scalar field decay before the nucleosynthesis epoch,
and find a larger expansion rate at the electroweak scale than the one obtained
in Ref. 1. The decaying field models suffer however from an entropy release
that dilutes the baryon number produced at the electroweak scale. This dilution
is minimized when the kinetic scalar field mode dominates (w_phi = 1), singling
it out as the preferred cosmology with regard to baryogenesis. We study both
cases, the electroweak transition with an expansion driven departure from
equilibrium, and a first order phase transition. We show that in the former
case with some tuning one can produce the amount of matter consistent with
observation. In the latter case the expansion rate at the electroweak scale may
be almost as large as the symmetric phase sphaleron rate, so that even the
electroweak models with a relatively weak first order phase transition can be
viable for baryogenesis.

</DOC>
<DOC>
<DOCNO> 7925 </DOCNO>
Electron momentum distribution in underdoped cuprates


  We investigate the electron momentum distribution function (EMD) in a weakly
doped two-dimensional quantum antiferromagnet (AFM) as described by the t-J
model. Our analytical results for a single hole in an AFM based on the
self-consistent Born approximation (SCBA) indicate an anomalous momentum
dependence of EMD showing 'hole pockets' coexisting with a signature of an
emerging large Fermi surface. The position of the incipient Fermi surface and
the structure of the EMD is determined by the momentum of the ground state. Our
analysis shows that this result remains robust in the presence of next-nearest
neighbor hopping terms in the model. Exact diagonalization results for small
clusters are with the SCBA reproduced quantitatively.

</DOC>
<DOC>
<DOCNO> 100861 </DOCNO>
From Coherent Structures to Universal Properties


  Given a 2-category $\twocat{K}$ admitting a calculus of bimodules, and a
2-monad T on it compatible with such calculus, we construct a 2-category
$\twocat{L}$ with a 2-monad S on it such that: (1)S has the
adjoint-pseudo-algebra property. (2)The 2-categories of pseudo-algebras of S
and T are equivalent. Thus, coherent structures (pseudo-T-algebras) are
transformed into universally characterised ones (adjoint-pseudo-S-algebras).
The 2-category $\twocat{L}$ consists of lax algebras for the pseudo-monad
induced by T on the bicategory of bimodules of $\twocat{K}$. We give an
intrinsic characterisation of pseudo-S-algebras in terms of representability.
Two major consequences of the above transformation are the classifications of
lax and strong morphisms, with the attendant coherence result for
pseudo-algebras. We apply the theory in the context of internal categories and
examine monoidal and monoidal globular categories (including their monoid
classifiers) as well as pseudo-functors into $\Cat$.

</DOC>
<DOC>
<DOCNO> 12400 </DOCNO>
Interfacial Tension of Electrolyte Solutions


  A theory is presented to account for the increase in surface tension of water
in the presence of electrolyte. Unlike the original ``grand-canonical''
calculation of Onsager and Samaras, which relied on the Gibbs adsorption
isotherm and lead to a result which could only be expressed as an infinite
series, our approach is ``canonical'' and produces an analytic formula for the
excess surface tension. For small concentrations of electrolyte, our result
reduces to the Onsager-Samaras limiting law.

</DOC>
<DOC>
<DOCNO> 85028 </DOCNO>
Global phase time and path integral for string cosmological models


  A global phase time is identified for homogeneous and isotropic cosmological
models yielding from the low energy effective action of closed bosonic string
theory. When the Hamiltonian constraint allows for the existence of an
intrinsic time, the quantum transition amplitude is obtained by means of the
usual path integral procedure for gauge systems.

</DOC>
<DOC>
<DOCNO> 152555 </DOCNO>
SO and Sp Chern-Simons at Large N


  We study the large N limit of SO(N) and Sp(N) Chern-Simons gauge theory on
S^3 and identify its closed string dual as topological strings on an
orientifold of the small resolution of the conifold. Applications to large N
dualities for N=1 supersymmetric gauge systems in 4 dimensions are also
discussed.

</DOC>
<DOC>
<DOCNO> 70461 </DOCNO>
Neutral heavy lepton production at next high energy $e^+e^-$ linear


  The discovery potential for detecting new heavy Majorana and Dirac neutrinos
at some recently proposed high energy $e^+e^-$ colliders is discussed. These
new particles are suggested by grand unified theories and superstring-inspired
models. For these models the production of a single heavy neutrino is shown to
be more relevant than pair production when comparing cross sections and
neutrino mass ranges.
  The process $ e^+e^- \longrightarrow {\nu} e^{\pm} W^{\mp}$ is calculated
including on-shell and off-shell heavy neutrino effects.
  We present a detailed study of cross sections and distributions that shows a
clear separation between the signal and standard model contributions, even
after including hadronization effects.

</DOC>
<DOC>
<DOCNO> 80818 </DOCNO>
Vortices and monopole distributions in $Z(2) \times SO(3)$ lattice gauge


  We examine the occurance of Z(2) and SO(3) vorticies and monopole
distributions in the neighborhood of Wilson loops. We use the Tomboulis
formulation, equivalent to the Wilson action, in which the links are invariant
under Z(2) transformations and new plaquette variables carry the Z(2) degrees
of freedom. This gives new gauge invariant observables to help gain insight
into the area law and structure of the flux tube.

</DOC>
<DOC>
<DOCNO> 11899 </DOCNO>
Dissipationless flow and superfluidity in gaseous Bose-Einstein


  We study dissipation in a dilute Bose gas induced by the motion of a
macroscopic object. A blue-detuned laser beam focused on the center of a
trapped gas of sodium atoms was scanned both above and below the BEC transition
temperature. The measurements allow for a comparison between the heating rates
for the superfluid and normal gas.

</DOC>
<DOC>
<DOCNO> 117135 </DOCNO>
Deterministic chaos, fractals and quantumlike mechanics in atmospheric


  The complex spaciotemporal patterns of atmospheric flows that result from the
cooperative existence of fluctuations ranging in size from millimetres to
thousands of kilometres are found to exhibit long-range spacial and temporal
correlations. These correlations are manifested as the self-similar fractal
geometry of the global cloud cover pattern and the inverse power-law form for
the atmospheric eddy energy spectrum. Such long-range spaciotemporal
correlations are ubiquitous in extended natural dynamical systems and are
signatures of deterministic chaos or self-organized criticality. In this paper,
a cell dynamical system model for atmospheric flows is developed by
consideration of microscopic domain eddy dynamical processes. This
nondeterministic model enables formulation of a simple closed set of governing
equations for the prediction and description of observed atmospheric flow
structure characteristics as follows. The strange-attractor design of the field
of deterministic chaos in atmospheric flows consists of a nested continuum of
logarithmic spiral circulations that trace out the quasi-periodic Penrose
tiling pattern, identified as the quasi-crystalline structure in condensed
matter physics. The atmospheric eddy energy structure follows laws similar to
quantum mechanical laws. The apparent wave-particle duality that characterize
quantum mechanical laws is attributed to the bimodal phenomenological form of
energy display in the bidirectional energy flow that is intrinsic to eddy
circulations, e.g., formation of clouds in updrafts and dissipation of clouds
in downdrafts that result in the observed discrete cellular geometry of cloud
structure.

</DOC>
<DOC>
<DOCNO> 169855 </DOCNO>
Error Avoiding Quantum Codes and Dynamical Stabilization of Grover's


  An error avoiding quantum code is presented which is capable of stabilizing
Grover's quantum search algorithm against a particular class of coherent
errors. This error avoiding code consists of states only which are factorizable
in the computational basis. Furthermore, its redundancy is smaller than the one
which is achievable with a general error correcting quantum code saturating the
quantum Hamming bound. The fact that this code consists of factorizable states
only may offer advantages for the implementation of quantum gates in the error
free subspace.

</DOC>
<DOC>
<DOCNO> 174485 </DOCNO>
Backward emitted high-energy neutrons in hard reactions of p and pi^+ on


  Beams of protons and pions of 5.9 GeV/c were incident on a C target. Neutrons
emitted into the back hemisphere, in the laboratory system, were detected in
(triple) coincidence with two emerging $p_t>$0.6 GeV/c particles. We present
the momentum spectra of the backward going neutrons, which have the same
universal shape observed in earlier (inclusive) reactions induced by hadrons,
$\gamma$, $\nu$, and $\bar{\nu}$ beams. We also integrated the spectra and
determined the fraction of the hard scattering events which are in coincidence
with at least one neutron emitted into the back hemisphere, with momenta above
0.32 GeV/c.
  Contrary to the earlier measurements which found that only a small fraction
(of the order of 10%) of the total inelastic cross section for light nuclei was
associated with backward going nucleons, we find that about half of the events
are of this nature. We speculate that the reason for the large difference is
the strong total center of mass (s) dependence of the hard reaction and short
range nucleon correlations in nuclei.

</DOC>
<DOC>
<DOCNO> 85226 </DOCNO>
The Numerical Evolution of Neutron Star Oscillations


  The present work investigates the numerical evolution of linearized
oscillations of non-rotating, spherically symmetric neutron stars within the
framework of general relativity. We derive the appropriate equations using the
(3+1)-formalism. We first focus on the evolution of radial oscillations, which
do not emit gravitational waves. We demonstrate how to handle a numerical
instability that also occurs in the non-radial case, when the stellar model is
constructed based on a realistic equation of state. We devise a coordinate
transformation that not only removes this instability but also provides much
more accurate results. [...] The main part deals with the evolution of
non-radial oscillations (l >= 2) of neutron stars. Here, we compare different
formulations of the equations and discuss how they have to be numerically dealt
with in order to avoid instabilities at the origin. We present results for
various polytropic stellar models and different initial data. [...] In the last
part of this thesis we consider a physical mechanism for exciting oscillations
of neutron stars. We use the time dependent gravitational field of a small
point mass \mu that orbits the neutron star to induce stellar oscillations.
With this particle we have a physical means which removes the arbitrariness in
choosing the initial data. [...] By sampling various orbital parameters of the
particle we show that in general the particle is not able to excite any
w-modes. It is only for speeds very close to the speed of light that the w-mode
is a significant part of the wave signal.

</DOC>
<DOC>
<DOCNO> 10896 </DOCNO>
Pressure-induced residual resistivity anomaly in CeCu_5Au


  The electrical resistivity of the magnetically ordered CeCu_5Au has been
investigated under pressure up to 8.5 GPa. In the magnetically ordered region
(p<3.4 GPa) the residual resistivity rho_0 shows a pronounced maximum as a
function of pressure. Even in the nonmagnetic region rho_0 decreases
monotonically by more than a factor of three. These two effects can be
qualitatively explained in terms of the interplay of pressure, magnetism and
disorder in a strongly correlated electron system with weak disorder.

</DOC>
<DOC>
<DOCNO> 118583 </DOCNO>
Persistent fluctuations and scaling properties in galaxy number counts


  Counts of galaxies as a function of apparent magnitude are among the most
time-honored observations in cosmology. In this Letter, we focus on some
statistical properties of these counts which are fundamental in order to
characterize the large scale correlations in the galaxy spatial distribution.
There are, in fact, no longer doubts since two decades of the existence of very
large scale structures. The still remaining problem concerns the correct
characterization of their statistical properties. We propose to study two
properties of galaxy counts data, in order to discriminate between a small
scale (~ 5 - 20 Mpc/h) homogeneous distribution, and a fractal structure on
large scales (~ 20 - 300 Mpc/h). Firstly, the average slope of the counts which
can be associated to an eventual fractal dimension in real space by simple
arguments. Secondly, we propose to study fluctuations of counts around the
average behavior as a function of apparent magnitude in the whole magnitude
range B_j > 11. These fluctuations can discriminate between a genuine fractal
distribution and a homogeneous one. In fact, they are related to the very
statistical properties of the spatial distribution, independently on
cosmological corrections. More specifically, in a fractal distribution one
expects to find persistent scale-invariant fluctuations around the average
behavior, which do not decay with apparent magnitude. On the other hand, in an
homogeneous distribution, on large enough scales, the relative variance of the
counts should decrease exponentially with apparent magnitude. Smooth
cosmological corrections cannot change such a behavior.

</DOC>
<DOC>
<DOCNO> 9495 </DOCNO>
Nonmonotonic roughness evolution in unstable growth


  The roughness of vapor-deposited thin films can display a nonmonotonic
dependence on film thickness, if the smoothening of the small-scale features of
the substrate dominates over growth-induced roughening in the early stage of
evolution. We present a detailed analysis of this phenomenon in the framework
of the continuum theory of unstable homoepitaxy. Using the spherical
approximation of phase ordering kinetics, the effect of nonlinearities and
noise can be treated explicitly. The substrate roughness is characterized by
the dimensionless parameter $Q = W_0/(k_0 a^2)$, where $W_0$ denotes the
roughness amplitude, $k_0$ is the small scale cutoff wavenumber of the
roughness spectrum, and $a$ is the lattice constant. Depending on $Q$, the
diffusion length $l_D$ and the Ehrlich-Schwoebel length $l_{ES}$, five regimes
are identified in which the position of the roughness minimum is determined by
different physical mechanisms. The analytic estimates are compared by numerical
simulations of the full nonlinear evolution equation.

</DOC>
<DOC>
<DOCNO> 121491 </DOCNO>
Stellar models and Hyades: the Hipparcos test


  We compare theoretical stellar models for Main Sequence (MS) stars with the
Hipparcos database for the Hyades cluster to give a warning against the
uncritical use of available theoretical scenarios and to show how formal MS
fittings can be fortuitous if not fictitious. Moreover, we find that none of
the current theoretical scenarios appears able to account for an observed
mismatch between theoretical predictions and observations of the coolest Hyades
MS stars. Finally, we show that current theoretical models probably give too
faint He burning luminosities unlike the case of less massive He burning
models, with degenerate progenitors, which have been suggested to suffer the
opposite discrepancy.

</DOC>
<DOC>
<DOCNO> 72204 </DOCNO>
Radiative decay of a massive particle and the non-thermal process in


  We consider the effects on big bang nucleosynthesis (BBN) of the radiative
decay of a long-lived massive particle. If high-energy photons are emitted
after the BBN epoch ($t \sim 1 - 10^3$ sec), they may change the abundances of
the light elements through photodissociation processes, which may result in a
significant discrepancy between standard BBN and observation. Taking into
account recent observational and theoretical developments in this field, we
revise our previous study constraining the abundance of the
radiatively-decaying particles. In particular, on the theoretical side, it was
recently claimed that the non-thermal production of $^6$Li, which is caused by
the photodissociation of $\hefour$, most severely constrains the abundance of
the radiatively-decaying particle. We will see, however, it is premature to
emphasize the importance of the non-thermal production of $^6$Li because (i)
the theoretical computation of the $^6$Li abundance has large uncertainty due
to the lack of the precise understanding of the $^6$Li production cross
section, and (ii) the observational data of $^6$Li abundance has large errors.

</DOC>
<DOC>
<DOCNO> 68309 </DOCNO>
A New Source for Electroweak Baryogenesis in the MSSM


  One of the most experimentally testable explanations for the origin of the
baryon asymmetry of the universe is that it was created during the electroweak
phase transition, in the minimal supersymmetric standard model. Previous
efforts have focused on the current for the difference of the two Higgsino
fields, $H_1-H_2$, as the source of biasing sphalerons to create the baryon
asymmetry. We point out that the current for the orthogonal linear combination,
$H_1+H_2$, is larger by several orders of magnitude. Although this increases
the efficiency of electroweak baryogenesis, we nevertheless find that large
CP-violating angles $\ge 0.15$ are required to get a large enough baryon
asymmetry.

</DOC>
<DOC>
<DOCNO> 116456 </DOCNO>
Acoustic coupling between two air bubbles in water


  The acoustic coupling between two air bubbles immersed in water is clearly
demonstrated. The system is acoustically forced, and its response is detected.
The experimental results confirm that both theoretically predicted eigenmodes,
respectively symmetrical and antisymmetrical, do exist. Their frequencies,
measured as a function of the bubbles spacing, follow theoretical estimations
within a 10% accuracy.

</DOC>
<DOC>
<DOCNO> 12787 </DOCNO>
Chromatic Polynomials for Lattice Strips with Cyclic Boundary Conditions


  The zero-temperature $q$-state Potts model partition function for a lattice
strip of fixed width $L_y$ and arbitrary length $L_x$ has the form
$P(G,q)=\sum_{j=1}^{N_{G,\lambda}}c_{G,j}(\lambda_{G,j})^{L_x}$, and is
equivalent to the chromatic polynomial for this graph. We present exact
zero-temperature partition functions for strips of several lattices with
$(FBC_y,PBC_x)$, i.e., cyclic, boundary conditions. In particular, the
chromatic polynomial of a family of generalized dodecahedra graphs is
calculated. The coefficient $c_{G,j}$ of degree $d$ in $q$ is
$c^{(d)}=U_{2d}(\frac{\sqrt{q}}{2})$, where $U_n(x)$ is the Chebyshev
polynomial of the second kind. We also present the chromatic polynomial for the
strip of the square lattice with $(PBC_y,PBC_x)$, i.e., toroidal, boundary
conditions and width $L_y=4$ with the property that each set of four vertical
vertices forms a tetrahedron. A number of interesting and novel features of the
continuous accumulation set of the chromatic zeros, ${\cal B}$ are found.

</DOC>
<DOC>
<DOCNO> 9769 </DOCNO>
Multifractal Behaviour of n-Simplex Lattice


  We study the asymptotic behaviour of resistance scaling and fluctuation of
resistance that give rise to flicker noise in an {\em n}-simplex lattice. We
propose a simple method to calculate the resistance scaling and give a
closed-form formula to calculate the exponent, $\beta_L$, associated with
resistance scaling, for any n. Using current cumulant method we calculate the
exact noise exponent for n-simplex lattices.

</DOC>
<DOC>
<DOCNO> 151325 </DOCNO>
Effective action for QED_4 through zeta function regularization


  We obtain, through zeta function methods, the one-loop effective action for
massive Dirac fields in the presence of a uniform, but otherwise general,
electromagnetic background. After discussing renormalization, we compare our
zeta function result with Schwinger's proper time approach.

</DOC>
<DOC>
<DOCNO> 9300 </DOCNO>
Static and dynamic properties of ferroelectric thin film multilayers


  A thermodynamic theory of ferroelectric thin film multilayers is developed.
The free energy function is written down using a multilayer model in which
c-domain layers of one ferroelectric material alternate with a-domain layers of
a second ferroelectric material. We assume that the interfaces are perfectly
sharp and that the polarization at these boundaries is zero. The
renormalization of the free energy coefficients due to the stresses in the
films and to the depolarizing field was taken into account, as well as the
renormalization of the coefficients of the polarization gradients. The
equilibrium inhomogeneous polarization temperature and its thickness dependence
were determined from the solutions of the Euler-Lagrange equations resulting
from the minimization of the free energy functional. A thickness induced
ferroelectric phase transition is shown to exist and its transition temperature
and critical layer thickness depend on the domain orientation. The criteria for
''a/c'', ''c/c'' and ''a/a'' domain multilayering are calculated and expressed
via coefficients of the free energy density and the layer thickness.
   The calculated multilayer susceptibility diverges at the transition
temperature of the thickness induced ferroelectric phase. This divergence is
shown to be the origin of the giant dielectric response observed in some
multilayers. The theory gives an excellent fit to the temperature dependence of
the giant susceptibility observed recently in multilayers of
PbTiO$_{3}$-Pb$_{1-x}$La$_{x}$TiO$_{3}$ ($x=0.28$).

</DOC>
<DOC>
<DOCNO> 169943 </DOCNO>
Renormalization Group Computation of Correlation Functions and Particle


  We show that the Renormalization Group formalism allows to compute with
accuracy the zero temperature correlation functions and particle densities of
quantum systems.

</DOC>
<DOC>
<DOCNO> 118771 </DOCNO>
Radiation Spectra of Advection Dominated Accretion Flows around Kerr


  We study the formation of the spectra in advection dominated accretion flows
(ADAFs) around Kerr black holes. We use a Monte Carlo approach and fully
general relativistic treatment to follow the paths of individual photons and
model their scattering with mildly relativistic, thermal electrons of the two
temperature plasma present in the flow. We study the influence of the accretion
rate, black hole mass, black hole angular momentum, and the strength of the
small scale magnetic field present in the plasma on the resulting spectra. The
impact of the black hole angular momentum on the spectra is present and can be
distinguished from the influence of changes in other parameters. This property
of the models should be taken into account when modeling the individual sources
and the population of inefficiently accreting black holes in the Universe.

</DOC>
<DOC>
<DOCNO> 118622 </DOCNO>
Temporal behaviour of emissions from Gamma-ray bursts and


  The CCD magnitudes in Cousins R and I photometric passbands are determined
for GRB 991216 and GRB 991208 afterglows respectively about 1 and about 3 day
after trigger of the corresponding gamma-ray bursts. Light curves of the
afterglow emissions are obtained by combining the published data with the
present measurements in R and I passbands for GRB 991208 and in R, Gunn I and J
passbands for GRB 991216. They indicate that the flux decay constants of a GRB
are almost the same in each passband with values about 2.2 for GRB 991208 and
about 1.2 for GRB 991216 indicating very fast optical flux decay in the case of
former which may be due to beaming effect. However, cause of steepening by 0.23
+/- 0.06 dex in the R light curve of GRB 991216 afterglow between 2 to 2.5 day
after the burst, is presently not understood. Redshift determinations indicate
that both GRBs are at cosmological distance with a value of 4.2 Gpc for GRB
991208 and 6.2 Gpc for GRB 991216. The observed fluence above 20 keV indicates,
if isotropic, release of energy about 1.3 x 10^{53} erg for GRB 991208 and
about 6.7 x 10^{53} erg for GRB 991216 by these bright gamma-ray flashes. The
enormous amount of released energy will be reduced, if the radiation is beamed
which seems to be case for GRB 991208 afterglow.The quasi-simultaneous
broad-band photometric spectral energy distributions of the afterglows are
determined about 8.5 day and about 35 hour after the bursts of GRB 991208 and
GRB 991216 respectively.The flux decreases exponentially with frequency. The
value of spectral index in the optical-near IR region is -0.75 +/- 0.03 for GRB
991208 and -1.0 +/- 0.12 for GRB 991216.

</DOC>
<DOC>
<DOCNO> 152056 </DOCNO>
An M-Theory Perspective on Heterotic K3 Orbifold Compactifications


  We analyze the structure of heterotic M-theory on K3 orbifolds by presenting
a comprehensive sequence of M-theoretic models constructed on the basis of
local anomaly cancellation. This is facilitated by extending the technology
developed in our previous papers to allow one to determine "twisted" sector
states in non-prime orbifolds. These methods should naturally generalize to
four-dimensional models, which are of potential phenomenological interest.

</DOC>
<DOC>
<DOCNO> 71370 </DOCNO>
Two-loop Radiative Corrections to Neutrino Masses in $SU(3)_L \times


  We have constructed two $SU(3)_L \times U(1)_N$ gauge models with the
$L^\prime = L_e-L_\mu-L_\tau$ symmetry, which accommodate tiny neutrino masses
generated by one-loop and two-loop radiative effects. The heavy neutral leptons
and heavy charged leptons are employed to specify the lepton triplets in
$SU(3)_L$, respectively, accompanied by ($\phi^0$, $\phi^-$, $h^+$) and
($\phi^+$, $\phi^0$, $h^+$), where $\phi$ stands for the standard Higgs scalar
and $h^+$ is a key ingredient for radiative mechanisms. From our numerical
calculations, we find that both our models are relevant to yield the VO
solution to the solar neutrino problem.

</DOC>
<DOC>
<DOCNO> 99880 </DOCNO>
Boundary actions for affine buildings and higher rank Cuntz-Krieger


  Let $\G$ be a group of type rotating automorphisms of an affine building
$\cB$ of type $\wt A_2$. If $\G$ acts freely on the vertices of $\cB$ with
finitely many orbits, and if $\Omega$ is the (maximal) boundary of $\cB$, then
$C(\Om)\rtimes \G$ is a p.i.s.u.n. $C^*$-algebra. This algebra has a structure
theory analogous to that of a simple Cuntz-Krieger algebra and is the
motivation for a theory of higher rank Cuntz-Krieger algebras, which has been
developed by T. Steger and G. Robertson. The K-theory of these algebras can be
computed explicitly in the rank two case. For the rank two examples of the form
$C(\Om)\rtimes \G$ which arise from boundary actions on $\wt A_2$ buildings,
the two K-groups coincide.

</DOC>
<DOC>
<DOCNO> 83479 </DOCNO>
A syntactical analysis of non-size-increasing polynomial time


  A syntactical proof is given that all functions definable in a certain affine
linear typed lambda-calculus with iteration in all types are polynomial time
computable. The proof provides explicit polynomial bounds that can easily be
calculated.

</DOC>
<DOC>
<DOCNO> 119187 </DOCNO>
Candidate RR Lyrae Stars Found in Sloan Digital Sky Survey Commissioning


  We present a sample of 148 candidate RR Lyrae stars selected from Sloan
Digital Sky Survey (SDSS) commissioning data for about 100 deg2 of sky surveyed
twice with Delta(t) = 1.9946 days. Although the faint magnitude limit of the
SDSS allows us to detect RR Lyrae stars to large galactocentric distances
(about 100 kpc, or r = 21), we find no candidates fainter than r = 20, i.e.
further than about 65 kpc from the Galactic center. On the assumption that all
148 candidates are indeed RR Lyrae stars (contamination by other species of
variable star is probably less than 10%), we find that their volume density has
roughly a power-law dependence on galactocentric radius, 1/R^(2.7+-0.2),
between 10 and 50 kpc, and drops abruptly at R = 50-60 kpc, possibly indicating
a sharp edge to the stellar halo as traced by RR Lyrae stars.
  The Galactic distribution of stars in this sample is very inhomogeneous and
shows a clump of over 70 stars at about 45 kpc from the Galactic center. This
clump is also detected in the distribution of nonvariable objects with RR Lyrae
star colors. When sources in the clump are excluded, the best power-law fit
becomes consistent with the 1/R^3 distribution found from surveys of bright RR
Lyrae stars. These results imply that the halo contains clumpy overdensities
inhomogeneously distributed within a smooth 1/R^3 background, with a possible
cutoff at about 50 kpc.

</DOC>
<DOC>
<DOCNO> 12710 </DOCNO>
Formation of a magnetic soliton lattice in copper metaborate


  The magnetic ground-state of copper metaborate is investigated by means of
elastic neutron scattering.The magnetic structure of CuB2O4 is incommensurate
with respect to the chemical lattice at T=1.8K and undergoes a continuous phase
transition to a non-collinear commensurate antiferromagnetic state which is
realized at T=10K. Close to the phase transition higher-order magnetic
satellites are observed. Coexistence of long-range and short range magnetic
order observed in both magnetic phases. This suggests that the association of
the Dzyialoshinskii-Moriya interaction, lattice symmetry and tetragonal
anisotropy leads to the formation of a three-dimensional magnetic soliton
lattice.

</DOC>
<DOC>
<DOCNO> 99631 </DOCNO>
Dominos and the Gaussian free field


  We define a scaling limit of the height function on the domino tiling model
(dimer model) on simply-connected regions in Z^2 and show that it is the
``massless free field'', a Gaussian process with independent coefficients when
expanded in the eigenbasis of the Laplacian.

</DOC>
<DOC>
<DOCNO> 100789 </DOCNO>
Perurbation expansions for the spiked harmonic oscillator and related


  We study weak-coupling perturbation expansions for the ground-state energy of
the Hamiltonian with the generalized spiked harmonic oscillator potential V(x)
= Bx^2 + A/x^2 + lambda/x^alpha, and also for the bottoms of the angular
momentum subspaces labelled by ell = 0,1,2 ..., in N-dimensions corresponding
to the spiked harmonic oscillator potential: V(x) = x^2 + lambda/x^alpha, where
alpha is a real positive parameter. A method of Znojil is then applied to
obtain closed form expressions for the sums of some infinite series whose terms
involve ratios and products of gamma functions.

</DOC>
<DOC>
<DOCNO> 70067 </DOCNO>
Neutrino Mixing and CP Violation in Matter


  Within the framework of three lepton families I present a transparent
analytical relationship between the neutrino mixing and CP-violating parameters
in vacuum and thos in matter. Such a model- and parametrization-independent
result will be particularly useful to recast the fundamental lepton flavor
mixing matrix from the future long-baseline neutrino experiments.

</DOC>
<DOC>
<DOCNO> 102028 </DOCNO>
Solution of Belousov's problem


  The authors prove that a local $n$-quasigroup defined by the equation x_{n+1}
= F (x_1, ..., x_n) = [f_1 (x_1) + ... + f_n (x_n)]/[x_1 + ... + x_n], where
f_i (x_i), i, j = 1, ..., n, are arbitrary functions, is irreducible if and
only if any two functions f_i (x_i) and f_j (x_j), i \neq j, are not both
linear homogeneous, or these functions are linear homogeneous but f_i (x_i)/x_i
\neq f_j (x_j)/x_j. This gives a solution of Belousov's problem to construct
examples of irreducible $n$-quasigroups for any n \geq 3.

</DOC>
<DOC>
<DOCNO> 69925 </DOCNO>
Quarkonium Decays and Production in NRQCD


  Some examples of the most recent applications of the NRQCD factorization
approach to quarkonium phenomenology are presented. In the first part of the
talk the NLO calculations for $\chicj$ and $\Upsilon$ decays rates are compared
to the data and the results critically analyzed. In the second part, I show how
information on the non-perturbative matrix elements can be extracted from the
hadronic fixed-target experiments and eventually used to test their
universality.

</DOC>
<DOC>
<DOCNO> 170672 </DOCNO>
Giant Radiative Interactions Among Distant Atoms


  We examine the feasibility of enhancing the fundamental radiative
interactions between distant atoms. We present general arguments for producing
enhancement. In particular, we show how giant dipole-dipole interaction can be
produced by considering dipoles placed close to micron sized silica spheres.
The giant interaction arises as the whispering gallery modes can resonantly
couple the dipoles.

</DOC>
<DOC>
<DOCNO> 122623 </DOCNO>
The Density Probability Distribution Function in Turbulent, Isothermal,


  We investigate the behavior of the magnetic pressure, $b^2$, in fully
turbulent MHD flows in ``1+2/3'' dimensions by means of its effect on the
probability density function (PDF) of the density field. We start by reviewing
our previous results for general polytropic flows, according to which the value
of the polytropic exponent $\gamma$ determines the functional shape of the PDF.
A lognormal density PDF appears in the isothermal ($\gamma=1$) case, but a
power-law tail at either large or small densities appears for large Mach
numbers when $\gamma >1$ and $\gamma < 1$, respectively. In the isothermal
magnetic case, the relevant parameter is the field fluctuation amplitude,
$\dbb$. A lognormal PDF still appears for small field fluctuations (generally
the case for {\it large mean fields}), but a significant low-density excess
appears at large fluctuation amplitudes ({\it weak mean fields}), similar to
the behavior at $\gamma > 1$ of polytropic flows. We interpret these results in
terms of simple nonlinear MHD waves, for which the magnetic pressure behaves
linearly with the density in the case of the slow mode, and quadratically in
the case of the fast wave. Finally, we discuss some implications of these
results, in particular the fact that the effect of the magnetic field in
modifying the PDF is strongest when the mean field is weak.

</DOC>
<DOC>
<DOCNO> 68990 </DOCNO>
The H -> gamma gamma in Multi-Higgs doublet models


  We study the dominant decays of the lightest Higgs boson in models with 2 and
3 Higgs doublets, for the case when its couplings to fermions are absent at
tree-level. It is found that the branching ratio for the decay $H\to
\gamma\gamma$ is above the one into fermion pairs, which is evaluated also at
the 1-loop level.

</DOC>
<DOC>
<DOCNO> 102052 </DOCNO>
Quantum Jordanian twist


  The quantum deformation of the Jordanian twist F_qJ for the standard quantum
Borel algebra U_q(B) is constructed. It gives the family U_qJ(B) of quantum
algebras depending on parameters x and h. In a generic point these algebras
represent the hybrid (standard-nonstandard) quantization. The quantum Jordanian
twist can be applied to the standard quantization of any Kac-Moody algebra. The
corresponding classical r-matrix is a linear combination of the Drinfeld- Jimbo
and the Jordanian ones. The obtained two-parametric families of Hopf algebras
are smooth and for the limit values of the parameters the standard and
nonstandard quantizations are recovered. The twisting element F_qJ also has the
correlated limits, in particular when q tends to unity it acquires the
canonical form of the Jordanian twist. To illustrate the properties of the
quantum Jordanian twist we construct the hybrid quantizations for U(sl(2)) and
for the corresponding affine algebra U(hat(sl(2))). The universal quantum
R-matrix and its defining representation are presented.

</DOC>
<DOC>
<DOCNO> 13702 </DOCNO>
Temporal Correlations and Persistence in the Kinetic Ising Model: the


  We study the statistical properties of the sum $S_t=\int_{0}^{t}dt'
\sigma_{t'}$, that is the difference of time spent positive or negative by the
spin $\sigma_{t}$, located at a given site of a $D$-dimensional Ising model
evolving under Glauber dynamics from a random initial configuration. We
investigate the distribution of $S_{t}$ and the first-passage statistics
(persistence) of this quantity. We discuss successively the three regimes of
high temperature ($T>T_{c}$), criticality ($T=T_c$), and low temperature
($T<T_{c}$). We discuss in particular the question of the temperature
dependence of the persistence exponent $\theta$, as well as that of the
spectrum of exponents $\theta(x)$, in the low temperature phase. The
probability that the temporal mean $S_t/t$ was always larger than the
equilibrium magnetization is found to decay as $t^{-\theta-\frac12}$. This
yields a numerical determination of the persistence exponent $\theta$ in the
whole low temperature phase, in two dimensions, and above the roughening
transition, in the low-temperature phase of the three-dimensional Ising model.

</DOC>
<DOC>
<DOCNO> 11235 </DOCNO>
Dynamics and Critical Behaviour of the q-model


  The $q$-model, a random walk model rich in behaviour and applications, is
investigated. We introduce and motivate the $q$-model via its application
proposed by Coppersmith {\em et al.} to the flow of stress through granular
matter at rest. For a special value of its parameters the $q$-model has a
critical point that we analyse. To characterise the critical point we imagine
that a uniform load has been applied to the top of the granular medium and we
study the evolution with depth of fluctuations in the distribution of load.
Close to the critical point explicit calculation reveals that the evolution of
load exhibits scaling behaviour analogous to thermodynamic critical phenomena.
The critical behaviour is remarkably tractable: the harvest of analytic results
includes scaling functions that describe the evolution of the variance of the
load distribution close to the critical point and of the entire load
distribution right at the critical point, values of the associated critical
exponents, and determination of the upper critical dimension. These results are
of intrinsic interest as a tractable example of a random critical point. Of the
many applications of the q-model, the critical behaviour is particularly
relevant to network models of river basins, as we briefly discuss. Finally we
discuss circumstances under which quantum network models that describe the
surface electronic states of a quantum Hall multilayer can be mapped onto the
classical $q$-model. For mesoscopic multilayers of finite circumference the
mapping fails; instead a mapping to a ferromagnetic supersymmetric spin chain
has proved fruitful. We discuss aspects of the superspin mapping and give a new
elementary derivation of it making use of operator rather than functional
methods.

</DOC>
<DOC>
<DOCNO> 117562 </DOCNO>
Suppressing Linear Power on Dwarf Galaxy Halo Scales


  Recently is has been suggested that the dearth of small halos around the
Milky Way arises due to a modification of the primordial power spectrum of
fluctuations from inflation. Such modifications would be expected to alter the
formation of structure from bottom-up to top-down on scales near where the
short-scale power has been suppressed. Using cosmological simulations we study
the effects of such a modification of the initial power spectrum. While the
halo multiplicity function depends primarily on the linear theory power
spectrum, most other probes of power are more sensitive to the non-linear power
spectrum. Collapse of large-scale structures as they go non-linear regenerates
a ``tail'' in the power spectrum, masking small-scale modifications to the
primordial power spectrum except at very high-z. Even the small-scale
(k>2h/Mpc) clustering of the Ly-alpha forest is affected by this process, so
that CDM models with sufficient power suppression to reduce the number of 10^10
Msun halos by a factor of about 5 give similar Ly-alpha forest power spectrum
results. We conclude that other observations that depend more directly on the
number density of collapsed objects, such as the number of damped Ly-alpha
systems, or the redshift of reionization may provide the most sensitive tests
of these models.

</DOC>
<DOC>
<DOCNO> 121192 </DOCNO>
The Cluster of Galaxies Abell 970


  We present a dynamical analysis of the galaxy cluster Abell 970 based on a
new set of radial velocities measured at ESO, Pic du Midi and Haute-Provence
observatories. Our analysis indicates that this cluster has a substructure and
is out of dynamical equilibrium. This conclusion is also supported by
differences in the positions of the peaks of the surface density distribution
and X-ray emission, as well as by the evidence of a large scale velocity
gradient in the cluster. We also found a discrepancy between the masses
inferred with the virial theorem and with the X-ray emission, what is expected
if the galaxies and the gas inside the cluster are not in hydrostatic
equilibrium. Abell 970 has a modest cooling flow, as is expected if it is out
of equilibrium as suggested by Allen (1998). We propose that cooling flows may
have an intermittent behavior, with phases of massive cooling flows being
followed by phases without significant cooling flows after the acretion of a
galaxy group massive enough to disrupt the dynamical equilibrium in the center
of the clusters. A massive cooling flow will be established again, after a new
equilibrium is achieved.

</DOC>
<DOC>
<DOCNO> 120036 </DOCNO>
Substructures revealed by the Sunyaev-Zel'dovich effect at 150GHz in the


  We report on mapping observations toward the region of the most luminous
X-ray cluster RXJ1347-1145 (z=0.45) through the Sunyaev-Zel'dovich effect at
21GHz and 150GHz with the Nobeyama 45-m telescope. While a low angular
resolution image at 21GHz (beam-size of 76'') shows a consistent feature with
the ROSAT/HRI X-ray image, a higher angular resolution image (13'') at 150GHz
reveals complex morphological structures of the cluster region, which cannot be
simply described by the spherical isothermal beta-model. If such inhomogeneous
morphological features prove to be generic for high redshift clusters, distance
measurements to the clusters based on their Sunyaev-Zel'dovich data with low
angular resolution imaging should be interpreted with caution.

</DOC>
<DOC>
<DOCNO> 85492 </DOCNO>
Fourth-Order Ricci Gravity


  The Euler-Lagrange equations of motion for the most general Ricci type
gravitational Lagrangians are derived by means of a purely metric formalism.

</DOC>
<DOC>
<DOCNO> 150648 </DOCNO>
A Novel Superstring in Four Dimensions and Grand Unification


  A string in four dimensions is constructed by supplementing it with forty
four Majorana fermions. The central charge is 26. The fermions are grouped in
such a way that the resulting action is supersymmetric. The energy momentum and
current generators satisfy the super-Virasoro algebra. The tachyonic ground
state decouples from the physical states. GSO projections are necessary for
proving modular invariance. Space-time supersymmetry provides reasons to
discard the tachyons and is substantiated for modes of zero mass. The symmetry
group of the model descends to the low energy standard model group $SU (3)
\times SU_L (2) \times U_Y (1)$ through the Pati-Salam group. Left right
symmetry is broken spontaneously and the mass of the tau neutrino is calculated
to be about 1/25 electron volt.

</DOC>
<DOC>
<DOCNO> 70485 </DOCNO>
Lessons from Recent Measurements of CP Violation


  We review various implications of recent experimental results concerning CP
violation and mixing in $K\to\pi\pi$, $B\to\psi K_S$, $D\to K\pi$ and $D\to KK$
decays.

</DOC>
<DOC>
<DOCNO> 83344 </DOCNO>
Meta-Learning for Phonemic Annotation of Corpora


  We apply rule induction, classifier combination and meta-learning (stacked
classifiers) to the problem of bootstrapping high accuracy automatic annotation
of corpora with pronunciation information. The task we address in this paper
consists of generating phonemic representations reflecting the Flemish and
Dutch pronunciations of a word on the basis of its orthographic representation
(which in turn is based on the actual speech recordings). We compare several
possible approaches to achieve the text-to-pronunciation mapping task:
memory-based learning, transformation-based learning, rule induction, maximum
entropy modeling, combination of classifiers in stacked learning, and stacking
of meta-learners. We are interested both in optimal accuracy and in obtaining
insight into the linguistic regularities involved. As far as accuracy is
concerned, an already high accuracy level (93% for Celex and 86% for Fonilex at
word level) for single classifiers is boosted significantly with additional
error reductions of 31% and 38% respectively using combination of classifiers,
and a further 5% using combination of meta-learners, bringing overall word
level accuracy to 96% for the Dutch variant and 92% for the Flemish variant. We
also show that the application of machine learning methods indeed leads to
increased insight into the linguistic regularities determining the variation
between the two pronunciation variants studied.

</DOC>
<DOC>
<DOCNO> 68436 </DOCNO>
Photon Plus Jet Cross Sections in Deep Inelastic ep Collisions at Order


  The production of a hard and isolated photon accompanied by one or two jets
in large-Q2 deep inelastic ep scattering is calculated at next-to-leading
order. We include consistently contributions from quark-to-photon fragmentation
and study various differential cross sections and their dependence on isolation
cut parameters. Numerical results relevant for HERA experiments are presented.

</DOC>
<DOC>
<DOCNO> 7795 </DOCNO>
Distribution of forces and 'hydrodynamic clustering' in a shear


  Sheared concentrated colloids with short range polymer coats are examined via
simulations. Distributions of force are found to be sums of exponentials. The
'hydrodynamic clustering' underlying the shear thickening effect is shown, in
this system, to be a network of percolating coat contacts, with coats both in
compression and extension. The geometry and kinetics of this network are
explored along with its relation to the bulk stress tensor. Particles
experience strong fluctuations in force over epochs $\it{circa}$ 10% strain.
Density fluctuations up to glassy volume fractions give rise to scattering
peaks at low Q in the thickening regime. There is some commonality in the
physics of this colloid particulate system and other granular media.

</DOC>
<DOC>
<DOCNO> 120776 </DOCNO>
Ca II activity and rotation in F-K evolved stars


  (Abridged) Ca II H and K high resolution observations for 60 evolved stars in
the field and in 5 open clusters are presented. From these spectra
chromospheric fluxes are derived, and a homogeneous sample of more than 100
giants is built adding data from the literature. In addition, for most stars,
rotational velocities were derived from CORAVEL observations. By comparing
chromospheric emission in the cluster stars we confirm that chromospheric
activity depends on T_eff, and mass, when intermediate mass stars (M~4 Msun)
are considered. The Hyades and Praesepe clump giants show the same level of
activity, as expected from stars with similar masses and T_effs. A difference
of up to 0.4 dex in the chromospheric fluxes among the Hyades giants is
recorded and this sets a clear limit to the intrinsic spread of stellar
activity in evolved giants. Among the field stars none of the giants with
(V-R)<0.4 and Ia supergiants observed shows a signature of Ca II activity. We
find that chromospheric activity scales linearly with stellar rotational
velocity and a high power of stellar effective temperature: F'_k propto
T_eff^7.7 Vsini^0.9. This result can be interpreted as the effect of two
chromospheric components of different nature: one mechanical and one magnetic.
For each range of masses activity can simply be expressed as a function of only
one parameter: either the T_eff or the angular rotation Omega. For the 1.6-3
solar mass stars the data are consistent with I Omega=const, while lower and
higher masses follow a law similar to I Omega^2=const. We find it intriguing
that Vsini remains almost constant for 1Msun stars along their evolution; if a
similar behavior is shared by Pop II stars, this could explain the relatively
high degree of activity observed in Pop II giants.

</DOC>
<DOC>
<DOCNO> 14067 </DOCNO>
Preferencial growth: exact solution of the time dependent distributions


  We consider a preferential growth model where particles are added one by one
to the system consisting of clusters of particles. A new particle can either
form a new cluster (with probability q) or join an already existing cluster
with a probability proportional to the size thereof. We calculate exactly the
probability $\Pm_i(k,t)$ that the size of the i-th cluster at time t is k. We
analyze the asymptotics, the scaling properties of the size distribution and of
the mean size as well as the relation of our system to recent network models.

</DOC>
<DOC>
<DOCNO> 70882 </DOCNO>
Coherent production of hard dijets on nuclei in QCD


  We formulate the perturbative QCD approach to coherent diffractive dijet
production in pion-nucleon and pion-nucleus collisions at high energy. For hard
dijets the Pomeron splitting mechanism in which both helicity amplitudes are
proportional to the unintegrated gluon structure function of the proton and the
pion distribution amplitude is shown to dominate. In nuclear diffraction
multiple Pomeron splitting components are found to give antishadowing
contributions at large jet momentum. To leading twist there is an exact
cancelation of effects of nuclear attenuation and antishadowing/broadening of
multiple Pomeron splitting contributions. The next-to-leading higher twist
correction driven by nuclear rescatterings is calculable in hard QCD and proves
to be numerically very large. We argue that large higher twist effects do not
preclude the determination of gross features of the pion distribution
amplitude. Our results on the atomic mass number and momentum dependence of
dijet cross sections agree well with the preliminary findings from the E791
experiment.

</DOC>
<DOC>
<DOCNO> 40527 </DOCNO>
Prescise measurement of jet energies with the ZEUS detector


  A method to correct the jet transverse energy has been developed for the ZEUS
detector which attains an uncertainty better than 3%. The procedure is based on
a combination of tracking and calorimeter information that optimises the
resolution of reconstructed kinematic variables. The selected calorimeter
clusters and tracks are referred to as Energy Flow Objects (EFOs). The
conservation of energy and momentum in neutral current deep inelastic $e^+p$
scattering events is exploited to determine the required energy corrections by
balancing the scattered positron with the hadronic final state. The method has
been applied to data and simulated events independently. The corrected EFOs are
used as input to a $k_T$-cluster jet algorithm to reconstruct the jets and to
determine kinematic variables. In addition, the corrected EFOs allow an
improved measurement of the internal structure of a jet.

</DOC>
<DOC>
<DOCNO> 117570 </DOCNO>
Radio Properties of the Shapley Concentration. III. Merging Clusters in


  We present the results of a 22 cm radio survey carried out with the A3558
complex, a chain formed by the merging ACO clusters A3556-A3558-A3562 and
thetwo groups SC1327-312 and SC1323-313, located in the central region of the
complex, a chain formed by the merging ACO clusters A3556-A3558-A3562 and the
two groups SC1327-312 and SC1323-313, located in the central region of the
Shapley Concentration. The purpose of our survey is to study the effects of
cluster mergers on the statistical properties of radio galaxies and to
investigate the connection between mergers and the presence of radio halos and
relic sources. We found that the radio source counts in the A3558 complex are
consistent with the background source counts. Furthermore, we found that no
correlation exists between the local density and the radio source power, and
that steep spectrum radio galaxies are not segregated in denser optical
regions. The radio luminosity function for elliptical and S0 galaxies is
significantly lower than that for cluster type galaxies and for those not
selected to be in clusters at radio powers logP(1.4) > 22.5, implying that the
probability of a galaxy becoming a radio source above this power limit is lower
in the Shapley Concentration compared with any other environment. The detection
of a head-tail source in the centre of A3562, coupled with careful inspection
of the 20 cm NRAO VLA Sky Survey (NVSS) and of 36 cm MOST observations, allowed
us to spot two extended sources in the region between A3562 and SC1329-313,
i.e. a candidate radio halo at the centre of A3562, and low brightness extended
emission around a 14.96 magnitude Shapley galaxy.

</DOC>
<DOC>
<DOCNO> 70249 </DOCNO>
Testing the Correlation of Ultra-High Energy Cosmic Rays with High


  We study the correlation between compact radio quasars or 3EG gamma-ray
blazars and the arrival directions of cosmic rays above 10^19 eV using an
updated list of air shower detections. Our Monte Carlo simulations reveal no
significant correlations above random and some previous positive results appear
to be an effect of the small sample size. Consequently, unless somehow severely
deflected, there is no evidence for ultra-high energy cosmic ray primaries
being new particles or particles with new interactions beyond the electroweak
scale, produced in high-redshift active galactic nuclei.

</DOC>
<DOC>
<DOCNO> 151440 </DOCNO>
Induced Field Theory on the Brane World


  We show how the gravity, gauge, and matter fields are induced on dynamically
localized brane world (domain wall, vortex etc.). Solitonic solutions localized
on a curved brane in certain field theories in higher dimensions are given in
terms of gravity, gauge and extrinsic curvature fields of the brane. Then we
deduce the effective field theory on the brane in terms of those fields and the
quantum fluctuations of the solitonic solution. The gravity, gauge and the
extrinsic curvature fields should obey the Gauss-Codazzi-Ricci equation in
addition to their own equations of motion.

</DOC>
<DOC>
<DOCNO> 72071 </DOCNO>
Sgoldstino events in top decays at LHC


  We study top-quark decays in models with light sgoldstinos. The off-diagonal
entries in the squark mass matrices can lead to FCNC top two-body decays into
sgoldstinos and u(c) quarks. We compute the rates for these decays and discuss
the corresponding signatures that could manifest the presence of sgoldstinos in
top decays at LHC. We expect that a supersymmetry breaking scale $\sqrt{F}$ up
to a scale of order 10 TeV could be probed through this process, for a maximal
squark mixing with the third generation. Justified by our preliminary analysis,
a thorough study of the corresponding signal versus background and systematics
in the LHC environment would be most welcome, in order to accurately assess the
potential of this promising process in determining $\sqrt{F}$.

</DOC>
<DOC>
<DOCNO> 13990 </DOCNO>
The quantum Hall plateau transition at order 1/N


  The localization behavior of noninteracting two-dimensional electrons in a
random potential and strong magnetic field is of fundamental interest for the
physics of the quantum Hall effect. In order to understand the emergence of
power-law delocalization near the discrete extended-state energies $E_n = \hbar
\omega_c (n+{1/2})$, we study a generalization of the disorder-averaged
Liouvillian framework for the lowest Landau level to $N$ flavors of electron
densities (N=1 for the physical case). We find analytically the large-N limit
and 1/N corrections for all disorder strengths: at $N = \infty$ this gives an
estimate of the critical conductivity, and at order 1/N an estimate of the
localization exponent $\nu$. The localization properties of the analytically
tractable $N \gg 1$ theory seem to be continuously connected to those of the
exact quantum Hall plateau transition at $N = 1$.

</DOC>
<DOC>
<DOCNO> 11220 </DOCNO>
Band structure and atomic sum rules for x-ray dichroism


  Corrections to the atomic orbital sum rule for circular magnetic x-ray
dichroism in solids are derived using orthonormal LMTOs as a single-particle
basis for electron band states.

</DOC>
<DOC>
<DOCNO> 117541 </DOCNO>
Error analysis for stellar population synthesis as an inverse problem


  Stellar population synthesis can be approached as an inverse problem.
  The physical information is extracted from the observations through an
inverse model.
  The process requires the transformation of the observational errors into
model errors.
  A description is given for the error analysis to obtain objectively the
errors in the model. Finding a solution for overdetermined and under-determined
case was the purpose of two preceding papers. This new one completes the
problem of stellar populations synthesis by means of a data base, by providing
practical formul\ae defining the set of acceptable solutions. All solutions
within this set are compatible, at a given confidence level, with the
observations.

</DOC>
<DOC>
<DOCNO> 120538 </DOCNO>
Abundance gradients and their evolution in the Milky Way disk


  Based on a simple, but fairly successful, model of the chemical evolution of
the Milky Way disk, we study the evolution of the abundances of the elements
He, C, N, O, Ne, Mg, Al, Si, S, Ar and Fe. We use metallicity dependent yields
for massive stars with and without mass loss. We find that most observed
abundance profiles are correctly reproduced by massive star yields, but C and N
require supplementary sources. We argue that massive, mass losing stars can
totally account for the abundance profile of C, while intermediate mass stars
are the main source of N; in both cases, some conflict with corresponding data
on extragalactic HII regions arises, at least if current observations in the
Galaxy are taken at face value. The observed behaviour of Al is marginally
compatible with current massive star yields, which probably overestimate the
``odd-even'' effect. We also find that the adopted ``inside-out'' formation
scheme for the Milky Way disk produce abundance profiles steeper in the past.
The corresponding abundance scatter is smaller in the inner disk than in the
outer regions for a given interval of Galactic age.

</DOC>
<DOC>
<DOCNO> 8886 </DOCNO>
Electron - hole asymmetry and activation energy in quantum Hall


  We argue that the dissipative transport in ferromagnetic quantum Hall effect
liquids at $\nu=2N+1$ is dominated by the thermal activation of pairs
consisting of an electron and an antiskyrmion (topological texture which
represents a hole with 'screened' exchange interaction), thus manifesting the
lack of electron-hole symmetry in quantum Hall ferromagnets. We find that the
activation energy of such a pair is not the exchange energy, but is determined
by the interplay between the excess Zeeman energy of a skyrmion and the
charging energy of its topological texture: $${\cal E}=a\epsilon_{{\rm
Z}}^{1/3}E_{{\rm C}}^{2/3}\ln ^{1/3}(\frac{\Im_{i}}{E_{{\rm
C}}^{2/3}\epsilon_{{\rm Z}}^{1/3}}), E_{{\rm C}}=\frac{e^{2}}{\chi \lambda}, $$
with $ a\approx 1.75$.

</DOC>
<DOC>
<DOCNO> 123130 </DOCNO>
Far Ultraviolet Spectroscopy of a Nonradiative Shock in the Cygnus Loop:


  We present far ultraviolet spectra of a fast (~ 300 km/s) nonradiative shock
in the Cygnus Loop supernova remnant. Our observations were performed with the
Far Ultraviolet Spectroscopic Explorer (FUSE) satellite, covering the
wavelength range 905-1187 Angstroms. The purpose of these observations was to
estimate the degree of electron-ion equilibration by (1) examining the
variation of O VI 1032, 1038 intensity with position behind the shock, and (2)
measuring the widths of the O VI lines. We find significant absorption near the
center of the O VI 1032 line, with less absorption in O VI 1038. The absorption
equivalent widths imply an O VI column density greatly exceeding that of
interstellar O VI along the Cygnus Loop line of sight. We suggest that the
absorption may be due to resonant scattering by O VI ions within the shock
itself. The widths of the O VI emission lines imply efficient ion-ion
equilibration, in agreement with predictions from Balmer-dominated spectra of
this shock.

</DOC>
<DOC>
<DOCNO> 169844 </DOCNO>
Quantum Computation and the localization of Modular Functors


  The mathematical problem of localizing modular functors to neighborhoods of
points is shown to be closely related to the physical problem of engineering a
local Hamiltonian for a computationally universal quantum medium. For genus
$=0$ surfaces, such a local Hamiltonian is mathematically defined. Braiding
defects of this medium implements a representation associated to the Jones
polynomial and this representation is known to be universal for quantum
computation.

</DOC>
<DOC>
<DOCNO> 40076 </DOCNO>
Search for QCD Instanton-Induced Processes in Deep-Inelastic Scattering


  Preliminary H1 results on dedicated searches for QCD instanton induced
processes in DIS are presented. The investigations are based on the expected
characteristics of their hadronic final state. Searches were performed in the
kinematical region x > 0.001, 0.1 < y < 0.6 and the polar angle of scattered
positron greater than 156 degrees.

</DOC>
<DOC>
<DOCNO> 11028 </DOCNO>
Transport and Coulomb drag for two interacting carbon nanotubes


  We study nonlinear transport for two coupled one-dimensional quantum wires or
carbon nanotubes described by Luttinger liquid theory. Transport properties are
shown to crucially depend on the contact length $L_c$. For a special
interaction strength, the problem can be solved analytically for arbitrary
$L_c$. For point-like contacts and strong interactions, a qualitatively
different picture compared to a Fermi liquid emerges, characterized by
zero-bias anomalies and strong dependence on the applied cross voltage. In
addition, pronounced Coulomb drag phenomena are important for extended
contacts.

</DOC>
<DOC>
<DOCNO> 80804 </DOCNO>
3+1 dimensional Yang-Mills theory as a local theory of evolution of


  An explicit canonical transformation is constructed to relate the physical
subspace of Yang-Mills theory to the phase space of the ADM variables of
general relativity. This maps 3+1 dimensional Yang-Mills theory to local
evolution of metrics on 3 manifolds.

</DOC>
<DOC>
<DOCNO> 151301 </DOCNO>
Noncommutative SO(n) and Sp(n) Gauge Theories


  We study the generalization of noncommutative gauge theories to the case of
orthogonal and symplectic groups. We find out that this is possible, since we
are allowed to define orthogonal and symplectic subgroups of noncommutative
unitary gauge transformations even though the gauge potentials and gauge
transformations are not valued in the orthogonal and symplectic subalgebras of
the Lie algebra of antihermitean matrices. Our construction relies on an
antiautomorphism of the basic noncommutative algebra of functions which
generalizes the charge conjugation operator of ordinary field theory. We show
that the corresponding noncommutative picture from low energy string theory is
obtained via orientifold projection in the presence of a non-trivial NSNS
B-field.

</DOC>
<DOC>
<DOCNO> 99496 </DOCNO>
Rigidity and Vanishing Theorems in K-Theory II


  We extend our family rigidity and vanishing theorems in [{\bf LiuMaZ}] to the
Spin^c case. In particular, we prove a K-theory version of the main results of
[{\bf H}], [{\bf Liu1}, Theorem B] for a family of almost complex manifolds.

</DOC>
<DOC>
<DOCNO> 71808 </DOCNO>
Measuring the P-odd Pion-Nucleon Coupling h_{\pi NN}^{(1)} in \pi^+


  We show that polarized gamma p -> \pi^+ n in the threshold region is an
excellent candidate for measuring the leading parity-violating pion-nucleon
coupling h_{\pi NN}^{(1)} to an uncertainty of 20% if it has a natural size
from dimensional analysis. The conclusion is based on a large unpolarized cross
section, a new low-energy theorem for the photon polarization asymmetry at the
threshold A_\gamma|_{th} = \sqrt{2} f_\pi (\mu_p-\mu_n) h_{\pi NN}^{(1)}/g_A
m_N \sim h_{\pi NN}^{(1)}/2, and its strong dominance at forward and backward
angles in the threshold region.

</DOC>
<DOC>
<DOCNO> 99816 </DOCNO>
Correlations of measurement information and noise in quantum


  The original purpose of measurements is to provide us with information about
a previously unknown physical property of the system observed. In the Hilbert
space formalism of quantum mechanics, this physical meaning of measurement
information is not immediately apparent. In order to study the relationship
between the Hilbert space coherence of the quantum state and the measurement
information obtained in the laboratory, we introduce a generalized measurement
postulate for finite resolution measurements. With this measurement model,
correlations between non-commuting observables can be investigated. These
experimentally accessible correlations reveal nonclassical features in their
dependence on the operator ordering, reflecting the particular measurement
context by which they are determined.

</DOC>
<DOC>
<DOCNO> 102109 </DOCNO>
A relative Yoneda Lemma (manuscript)


  We construct set-valued right Kan-extensions via a relative Yoneda Lemma.

</DOC>
<DOC>
<DOCNO> 9504 </DOCNO>
Mott transition, antiferromagnetism, and unconventional


  The phase diagram of the layered organic superconductor
$\kappa$-(ET)$_{2}$Cu[N(CN)$_{2}$]Cl has been accurately measured from a
combination of $^{1}$H NMR and AC susceptibility techniques under helium gas
pressure. The domains of stability of antiferromagnetic and superconducting
long-range orders in the pressure {\it vs} temperature plane have been
determined. Both phases overlap through a first-order boundary that separates
two regions of inhomogeneous phase coexistence. The boundary curve is found to
merge with another first order line related to the metal-insulator transition
in the paramagnetic region. This transition is found to evolve into a crossover
regime above a critical point at higher temperature. The whole phase diagram
features a point-like region where metallic, insulating, antiferromagnetic and
non s-wave superconducting phases all meet.

</DOC>
<DOC>
<DOCNO> 8383 </DOCNO>
Velocity Autocorrelation and Harmonic Motion in Supercooled Nondiffusing


  Studies of the many-body potential surface of liquid sodium have shown that
it consists of a great many intersecting nearly harmonic valleys, a large
fraction of which have the same frequency spectra. This suggests that a
sufficiently supercooled state of this system, remaining in a single valley,
would execute nearly harmonic motion. To test this hypothesis, we have compared
$\hat{Z}(t)$, the normalized velocity autocorrelation function, calculated from
MD simulations to that predicted under the assumption of purely harmonic
motion. We find nearly perfect agreement between the two, suggesting that the
harmonic approximation captures all essential features of the motion.

</DOC>
<DOC>
<DOCNO> 12553 </DOCNO>
Second-quantization picture of the edge currents in the fractional


  We study the quantum theory of two-dimensional electrons in a magnetic field
and an electric field generated by a homogeneous background. The dynamics
separates into a microscopic and macroscopic mode. The latter is a circular
Hall current which is described by a chiral quantum field theory. It is shown
how in this second quantized picture a Laughlin-type wave function emerges.

</DOC>
<DOC>
<DOCNO> 40071 </DOCNO>
An Efficient Multiprocessor Management System for Event-Parallel


  Performance of software using TCP/IP sockets to distribute events to UNIX
workstations is described. This simple software was written at the University
of Mississippi to control UMiss farm reconstruction of 8 billion raw events,
part of Fermilab E791's data. E791 reconstructed HEP's largest data set to
study charm physics.

</DOC>
<DOC>
<DOCNO> 99825 </DOCNO>
Isospectral deformations of negatively curved Riemannian manifolds with


  To what extent does the eigenvalue spectrum of the Laplace-Beltrami operator
on a compact Riemannian manifold determine the geometry of the manifold? We
give examples of isospectral manifolds with different local geometry including
continuous families of isospectral negatively curved manifolds with boundary as
well as various pairs of manifolds. The latter illustrate that the spectrum
does not determine whether a manifold with boundary has negative curvature,
whether it has constant Ricci curvature, and whether it has parallel curvature
tensor, and the spectrum does not determine whether a closed manifold has
constant scalar curvature.

</DOC>
<DOC>
<DOCNO> 14042 </DOCNO>
Local Structure and Dynamics of Trans-polyisoprene oligomers


  Mono- and poly-disperse melts of oligomers (average length 10 monomers) of
trans-1,4-polyisoprene are simulated in full atomistic detail. The force-field
is developed by means of a mixture of ab initio quantum-chemistry and an
automatic generation of empirical parameters. Comparisons to NMR and scattering
experiments validate the model. The local reorientation dynamics shows that for
C$-$H vectors there is a two-stage process consisting of an initial decay and a
late-stage decorrelation originating from overall reorientation. The atomistic
model can be successfully mapped onto a simple model including only beads for
the monomers with bond springs and bond angle potentials. End-bridging Monte
Carlo as an equilibration stage and molecular dynamics as the subsequent
simulation method together prove to be a useful method for polymer simulations.

</DOC>
<DOC>
<DOCNO> 117592 </DOCNO>
The Fractional Kinetic Equation and Thermonuclear Functions


  The paper discusses the solution of a simple kinetic equation of the type
used for the computation of the change of the chemical composition in stars
like the Sun. Starting from the standard form of the kinetic equation it is
generalized to a fractional kinetic equation and its solutions in terms of
H-functions are obtained. The role of thermonuclear functions, which are also
represented in terms of G- and H-functions, in such a fractional kinetic
equation is emphasized. Results contained in this paper are related to recent
investigations of possible astrophysical solutions of the solar neutrino
problem.

</DOC>
<DOC>
<DOCNO> 70133 </DOCNO>
Transverse momentum distributions and their forward- backward


  The forward-backward correlations in the $p_T$ distributions, which present a
clear signature of non-linear effects in particle production, are studied in
the model of percolating colour strings. Quantitative predictions are given for
these correlations at SPS, RHIC and LHC energies. Interaction of strings also
naturally explains the flattening of $p_T$ distributions and increase of
$<p_T>$ with energy and atomic number for nuclear collisions

</DOC>
<DOC>
<DOCNO> 120045 </DOCNO>
Is there ERE in diffuse galactic light at high latitude?


  In 1998 Gordon, Witt and Friedmann wrote of detection of ERE in diffuse
galactic light at high latitudes. The comparaison of diffuse galactic light and
starlight over a few regions of the sky cannot, according to the authors, be
fully explained by extinction of starlight. 50% of the red interstellar light
needs to come from an interstellar emitting process.
  Different aspects of Gordon et al.'s data reduction work, and of the model
which supports their assertion, will be considered here. Analysis of the 100
micron emission of the regions Gordon et al. have studied will prove that the
color of the diffuse galactic light is explained by scattering of the
background starlight by dust embedded in nearby cirrus.
  ERE may not be present in diffuse galactic light, and, more generally, in
interstellar space.

</DOC>
<DOC>
<DOCNO> 169595 </DOCNO>
Causality and probabilistic interpretation of quantum mechanics


  It is shown that probabilistic treatment of quantum mechanics can be
coordinated with causality of all physical processes. The physical
interpretation of quantum-mechanical phenomena such as process of measurement
and collapse of quantum state is given.

</DOC>
<DOC>
<DOCNO> 69723 </DOCNO>
Small Neutrino Masses from Supersymmetry Breaking


  An alternative to the conventional see-saw mechanism is proposed to explain
the origin of small neutrino masses in supersymmetric theories. The masses and
couplings of the right-handed neutrino field are suppressed by supersymmetry
breaking, in a way similar to the suppression of the Higgs doublet mass, $\mu$.
New mechanisms for light Majorana, Dirac and sterile neutrinos arise, depending
on the degree of suppression. Superpartner phenomenology is greatly altered by
the presence of weak scale right-handed sneutrinos, which may have a coupling
to a Higgs boson and a left-handed sneutrino. The sneutrino spectrum and
couplings are quite unlike the conventional case - the lightest sneutrino can
be the dark matter and predictions are given for event rates at upcoming halo
dark matter direct detection experiments. Higgs decays and search strategies
are changed. Copious Higgs production at hadron colliders can result from
cascade decays of squarks and gluinos.

</DOC>
<DOC>
<DOCNO> 170731 </DOCNO>
Optical implementation of continuous-variable quantum cloning machines


  We propose an optical implementation of the Gaussian continuous-variable
quantum cloning machines. We construct a symmetric N -> M cloner which
optimally clones coherent states and we also provide an explicit design of an
asymmetric 1 -> 2 cloning machine. All proposed cloning devices can be built
from just a single non-degenerate optical parametric amplifier and several beam
splitters.

</DOC>
<DOC>
<DOCNO> 169787 </DOCNO>
Partial Teleportation of Entanglement in the Noisy Environment


  Partial teleportation of entanglement is to teleport one particle of an
entangled pair through a quantum channel. This is conceptually equivalent to
quantum swapping. We consider the partial teleportation of entanglement in the
noisy environment, employing the Werner-state representation of the noisy
channel for the simplicity of calculation. To have the insight of the many-body
teleportation, we introduce the measure of correlation information and study
the transfer of the correlation information and entanglement. We find that the
fidelity gets smaller as the initial-state is entangled more for a given
entanglement of the quantum channel. The entangled channel transfers at least
some of the entanglement to the final state.

</DOC>
<DOC>
<DOCNO> 178613 </DOCNO>
Comparison of Relativistic Nucleon-Nucleon Interactions


  We investigate the difference between those relativistic models based on
interpreting a realistic nucleon-nucleon interaction as a perturbation of the
square of a relativistic mass operator and those models that use the method of
Kamada and Gl\"ockle to construct an equivalent interaction to add to the
relativistic mass operator. Although both models reproduce the phase shifts and
binding energy of the corresponding non-relativistic model, they are not
scattering equivalent. The example of elastic electron-deuteron scattering in
the one-photon-exchange approximation is used to study the sensitivity of
three-body observables to these choices. Our conclusion is that the differences
in the predictions of the two models can be understood in terms of the
different ways in which the relativistic and non-relativistic $S$-matrices are
related. We argue that the mass squared method is consistent with conventional
procedures used to fit the Lorentz-invariant cross section as a function of the
laboratory energy.

</DOC>
<DOC>
<DOCNO> 8980 </DOCNO>
Noise Probe of the Dynamic Phase Separation in La2/3Ca1/3MnO3


  Giant Random Telegraph Noise (RTN) in the resistance fluctuation of a
macroscopic film of perovskite-type manganese oxide La2/3Ca1/3MnO3 has been
observed at various temperatures ranging from 4K to 170K, well below the Curie
temperature (TC = 210K). The amplitudes of the two-level-fluctuations (TLF)
vary from 0.01% to 0.2%. We use a statistical analysis of the life-times of the
TLF to gain insight into the microscopic electronic and magnetic state of this
manganite. At low temperature (below 30K) The TLF is well described by a
thermally activated two-level model. An estimate of the energy difference
between the two states is inferred. At higher temperature (between 60K and
170K) we observed critical effects of the temperature on the life-times of the
TLF. We discuss this peculiar temperature dependence in terms of a sharp change
in the free energy functional of the fluctuators. We attribute the origin of
the RTN to be a dynamic mixed-phase percolative conduction process, where
manganese clusters switch back and forth between two phases that differ in
their conductivity and magnetization.

</DOC>
<DOC>
<DOCNO> 170739 </DOCNO>
Non-dissipative decoherence bounds on quantum computation


  We investigate the capabilities of a quantum computer based on cold trapped
ions in presence of non-dissipative decoherence. The latter is accounted by
using the evolution time as a random variable and then averaging on a properly
defined probability distribution. Severe bounds on computational performances
are found.

</DOC>
<DOC>
<DOCNO> 151192 </DOCNO>
On the Thermodynamic Bethe Ansatz Equation in Sinh-Gordon Model


  Two implicit periodic structures in the solution of sinh-Gordon thermodynamic
Bethe ansatz equation are considered. The analytic structure of the solution as
a function of complex $\theta$ is studied to some extent both analytically and
numerically. The results make a hint how the CFT integrable structures can be
relevant in the sinh-Gordon and staircase models. More motivations are figured
out for subsequent studies of the massless sinh-Gordon (i.e. Liouville) TBA
equation.

</DOC>
<DOC>
<DOCNO> 150684 </DOCNO>
Untwisting Noncommutative R^d and the Equivalence of Quantum Field


  We show that there is a duality exchanging noncommutativity and non-trivial
statistics for quantum field theory on R^d. Employing methods of quantum
groups, we observe that ordinary and noncommutative R^d are related by
twisting. We extend the twist to an equivalence for quantum field theory using
the framework of braided quantum field theory. The twist exchanges both
commutativity with noncommutativity and ordinary with non-trivial statistics.
The same holds for the noncommutative torus.

</DOC>
<DOC>
<DOCNO> 67923 </DOCNO>
The chiral effective pion-nucleon Lagrangian of order p^4


  We construct the minimal effective chiral pion-nucleon SU(2) Lagrangian at
fourth order in the chiral expansion. The Lagrangian contains 118 in principle
measurable terms. We develop both the relativistic as well as the heavy baryon
formulation of the effective field theory. For the latter, we also work out
explicitly all 1/m corrections at fourth order. We display all relevant
relations needed to find the linearly independent terms.

</DOC>
<DOC>
<DOCNO> 9952 </DOCNO>
Thermostatistics of extensive and non-extensive systems using


  We describe in detail two numerical simulation methods valid to study systems
whose thermostatistics is described by generalized entropies, such as Tsallis.
The methods are useful for applications to non-trivial interacting systems with
a large number of degrees of freedom, and both short-range and long-range
interactions. The first method is quite general and it is based on the
numerical evaluation of the density of states with a given energy. The second
method is more specific for Tsallis thermostatistics and it is based on a
standard Monte Carlo Metropolis algorithm along with a numerical integration
procedure. We show here that both methods are robust and efficient. We present
results of the application of the methods to the one-dimensional Ising model
both in a short-range case and in a long-range (non-extensive) case. We show
that the thermodynamic potentials for different values of the system size N and
different values of the non-extensivity parameter q can be described by scaling
relations which are an extension of the ones holding for the Boltzmann-Gibbs
statistics (q=1). Finally, we discuss the differences in using standard or
non-standard mean value definitions in the Tsallis thermostatistics formalism
and present a microcanonical ensemble calculation approach of the averages.

</DOC>
<DOC>
<DOCNO> 150846 </DOCNO>
Anomalous N=2 superconformal Ward identities


  The N=2 superconformal Ward identities and their anomalies are discussed in
N=2 superspace (including N=2 harmonic superspace), at the level of the
low-energy effective action (LEEA) in four-dimensional N=2 supersymmetric field
theories. The (first) chiral N=2 supergravity compensator is related to the
known N=2 anomalous Ward identity in the N=2 (abelian) vector mulitplet sector.
As regards the hypermultiplet LEEA given by the N=2 non-linear sigma-model
(NLSM), a new anomalous N=2 superconformal Ward identity is found, whose
existence is related to the (second) analytic compensator in N=2 supergravity.
The celebrated solution of Seiberg and Witten is known to obey the (first)
anomalous Ward identity in the Coulomb branch. We find a few solutions to the
new anomalous Ward identity, after making certain assumptions about unbroken
internal symmetries. Amongst the N=2 NLSM target space metrics governing the
hypermultiplet LEEA are the SU(2)-Yang-Mills-Higgs monopole moduli-space
metrics that can be encoded in terms of the spectral curves (Riemann surfaces),
similarly to the Seiberg-Witten-type solutions. After a dimensional reduction
to three spacetime dimensions (3d), our results support the mirror symmetry
between the Coulomb and Higgs branches in 3d, N=4 gauge theories.

</DOC>
<DOC>
<DOCNO> 8666 </DOCNO>
Spectral Equivalence of Bosons and Fermions in One-Dimensional Harmonic


  Recently, Schmidt and Schnack (cond-mat/9803151, cond-mat/9810036), following
earlier references, reiterate that the specific heat of N non-interacting
bosons in a one-dimensional harmonic well equals that of N fermions in the same
potential. We show that this peculiar relationship between specific heats
results from a more dramatic equivalence between bose and fermi systems.
Namely, we prove that the excitation spectrums of such bose and fermi systems
are spectrally equivalent. Two complementary proofs are provided, one based on
an analysis of the dynamical symmetry group of the N-body system, the other
using combinatoric analysis.

</DOC>
<DOC>
<DOCNO> 69218 </DOCNO>
Q-ball collisions in the MSSM: gauge-mediated supersymmetry breaking


  Collisions of non-topological solitons, Q-balls, are considered in the
Minimal Supersymmetric Standard Model where supersymmetry has been broken at a
low energy scale via a gauge mediated mechanism. Q-ball collisions are studied
numerically on a two dimensional lattice for a range of Q-ball charges. Total
cross-sections, as well as fusion and geometrical cross-sections are
calculated. The total and geometrical cross-sections appear to converge with
increasing charge. The fusion cross-section has been estimated to be larger
than 60% of the geometrical cross-section for large balls.

</DOC>
<DOC>
<DOCNO> 70686 </DOCNO>
Dispersion analysis for generalized spin polarizabilities


  We report on a dispersion relation formalism for the virtual Compton
scattering (VCS) reaction on the proton, which for the first time allows a
dispersive evaluation of 4 generalized polarizabilities. The dispersion
formalism provides a new tool to analyze VCS experiments above pion threshold,
thus increasing the sensitivity to the generalized polarizabilities of the
nucleon.

</DOC>
<DOC>
<DOCNO> 116545 </DOCNO>
Effect of resonance radiative processes on the amplification factor


  Optimal conditions to acomplish amplification without inversion in
three-level schemes based on quantum nonlinear interference effects are
analyzed. Specific features of relaxation processes in optical transitions
seting these conditions apart from those in microwave schemes are outlined.
Numerical evaluations related to neon 2s_2-2p_4-3s_2 transitions are given.

</DOC>
<DOC>
<DOCNO> 69601 </DOCNO>
Results on Diffraction at HERA and Tevatron


  Recent results on diffraction at HERA, from the H1 and ZEUS Collaborations,
and at Tevatron, from the CDF and D0 Collaborations, are reviewed. The
measurement of the diffractive structure function at HERA is presented, and the
pomeron structure function is extracted from QCD fits. Diffractive dijet
production is given as an example analysis of the diffractive final state.
These analysis are consistent with a leading gluon partonic structure for the
pomeron. Hard single diffraction, double diffraction and double pomeron
exchange processes are studied at the Tevatron and complement the studies
performed at HERA. Finally, HERA results on the diffractive (exclusive)
production of a vector particle, either a vector meson or a photon, are
presented and compared to models based on perturbative QCD.

</DOC>
<DOC>
<DOCNO> 11839 </DOCNO>
Theory of plastic vortex creep


  We develop a theory for plastic flux creep in a topologically disordered
vortex solid phase in type-II superconductors. We propose a detailed
description of the plastic vortex creep of the dislocated, amorphous vortex
glass in terms of motion of dislocations driven by a transport current $j$. The
{\em plastic barriers} $U_{pl}(j)\propto j^{-\mu}$ show power-law divergence at
small drives with exponents $\mu=1$ for single dislocation creep and $\mu =
2/5$ for creep of dislocation bundles. The suppression of the creep rate is a
hallmark of the transition from the topologically ordered vortex lattice to an
amorphous vortex glass, reflecting a jump in $\mu$ from $\mu = 2/11$,
characterizing creep in the topologically ordered vortex lattice near the
transition, to its plastic values. The lower creep rates explain the observed
increase in apparent critical currents in the dislocated vortex glass.

</DOC>
<DOC>
<DOCNO> 13338 </DOCNO>
Multi-particle States in Spin-1 Chain System CsNiCl3


  A continuum of magnetic states has been observed by neutron scattering from
the spin-1 chain compound CsNiCl3 in its disordered gapped one-dimensional
phase. Results using both triple-axis and time-of-flight spectrometers show
that around the antiferromagnetic point Qc=pi, the continuum lies higher in
energy than the Haldane gapped excitations. At 6K the integrated intensity of
the continuum is about 12(2)% of the total spectral weight. This result is
considerably larger than the 1-3% weight predicted by the non-linear sigma
model for the 3-particle continuum.

</DOC>
<DOC>
<DOCNO> 121610 </DOCNO>
Modelling of Polarization Properties of Cometary Dust Grains


  Observational data for dusty comets are summarized and systemized.
  The dependence of the linear polarization on various parameters (the phase
angle, wavelength, etc.) is analyzed. An ensemble of aligned spheroidal
particles having various sizes and chemical compositions is used to fit the
linear and circular polarization observed for the comet Halley.

</DOC>
<DOC>
<DOCNO> 152116 </DOCNO>
Fuzzy Sphere from Matrix Model


  Using a D0-brane as a probe, we study the spacetime geometry in the
neighborhood of N D-branes in matrix theory. We find that due to fermionic zero
modes, the coordinates of the probe in the transverse directions are
noncommutative, and the angular part is a fuzzy sphere.

</DOC>
<DOC>
<DOCNO> 72117 </DOCNO>
Beyond leading order effects in photon pair production at the Tevatron


  We discuss effects induced by beyond leading order contributions to photon
pair production. We point out that next to leading order contributions to the
fragmentation component of the signal lead to a change in the shape of
distributions. This is already mildly visible in present Tevatron data though
stringent isolation criteria tend to suppress the fragmentation component
considerably. We expect the effect to be experimentally confirmed in future
data samples with higher statistics which would serve as a precision test for
QCD.

</DOC>
<DOC>
<DOCNO> 122896 </DOCNO>
High-Redshift Quasars Found in Sloan Digital Sky Survey Commissioning


  We report the discovery of 27 quasars with redshifts between 3.58 and 4.49.
The objects were identified as high-redshift candidates based on their colors
in Sloan Digital Sky Survey commissioning data. The redshifts were confirmed
with low resolution spectra obtained at the Hobby-Eberly Telescope. The
quasars' $i^*$ magnitudes range from 18.55 to 20.97. Nearly 60% of the quasar
candidates observed are confirmed spectroscopically as quasars. Two of the
objects are Broad Absorption Line quasars, and several other quasars appear to
have narrow associated absorption features.

</DOC>
<DOC>
<DOCNO> 12662 </DOCNO>
Cosmic Strings and Cooper Pairs


  It is shown that it is possible for bound fermions on a cosmic string to form
a superconducting state. Due to the attractive force between them, particles
moving in opposite directions along the string form bound pairs. This involves
a similar mechanism to superconductivity in metals at low temperatures. The
method of Gorkov is used to analyse the system. In contrast to the situation in
metals, the unusual properties of the string fermion spectrum allow a massless
Abelian gauge field to provide the required attractive force. This results in
far stronger superconductivity than usual. A massive gauge field can also be
used, in which case the standard results apply.

</DOC>
<DOC>
<DOCNO> 70674 </DOCNO>
Like-sign dimuon charge asymmetry in the decay of B B-bar pairs


  We discuss the CP-violating dimuon charge asymmetry of events p p-bar ---> B
B-bar X ---> mu mu X in the Standard Model. Our conclusion is that the
asymmetry is larger than previously expected and may reach a few percent for
the (B_d^0, B-bar_d^0) system. The analysis is also extended to the Two Higgs
Doublet Model (Model II).

</DOC>
<DOC>
<DOCNO> 70400 </DOCNO>
Summary talk at the conference on the sigma resonance


  This report summarizes the most important results presented at the recent
conference held at the Yukawa Institute of Theoretical Physics in Kyoto,
devoted to the recently confirmed light sigma resonance. Remarkably, all
speakers at this meeting took the light sigma for granted and many mass and
width estimations near 500 MeV were presented. We emphasize that if the light
and broad sigma is accepted as a true resonance it explains many basic problems
of low energy hadronic physics in a simple way, especially if the linear sigma
model is used as an approximate effective low energy theory.

</DOC>
<DOC>
<DOCNO> 170133 </DOCNO>
Objective probabilities, quantum counterfactuals, and the ABL rule


  The ABL rule is derived as a tool of standard quantum mechanics. The
ontological significance of the existence of objective probabilities is
discussed. Objections by Kastner and others to counterfactual uses of the ABL
rule are refuted. Metaphysical presumptions leading to such views as Kastner is
defending in her Comment are examined and shown to be unwarranted.

</DOC>
<DOC>
<DOCNO> 11326 </DOCNO>
Grain boundary effects on magnetotransport in bi-epitaxial films of


  The low field magnetotransport of La$_{0.7}$Sr$_{0.3}$MnO$_3$ (LSMO) films
grown on SrTiO$_3$ substrates has been investigated. A high qualtity LSMO film
exhibits anisotropic magnetoresistance (AMR) and a peak in the
magnetoresistance close to the Curie temperature of LSMO. Bi-epitaxial films
prepared using a seed layer of MgO and a buffer layer of CeO$_2$ display a
resistance dominated by grain boundaries. One film was prepared with seed and
buffer layers intact, while a second sample was prepared as a 2D square array
of grain boundaries. These films exhibit i) a low temperature tail in the low
field magnetoresistance; ii) a magnetoconductance with a constant high field
slope; and iii) a comparably large AMR effect. A model based on a two-step
tunneling process, including spin-flip tunneling, is discussed and shown to be
consistent with the experimental findings of the bi-epitaxial films.

</DOC>
<DOC>
<DOCNO> 151272 </DOCNO>
Z(2) vortex solution in a field theory


  We present a finite energy topological Z(2) vortex solution in a 2+1
dimensional SO(3) gauge field theory minimally coupled to a matrix valued Higgs
field. The vortex carries a Z(2) magnetic charge and obeys a modulo two
addition property. The core of this vortex has a structure similar to that of
the Abrikosov vortex appearing in a type II superconductor. The implications of
this solution for Wilson loops are quite interesting. In two Euclidean
dimensions these vortices are instantons and a dilute gas of such vortices
disorders Wilson loops producing an area law behaviour with an exponentially
small string tension. In 2+1 dimensions the vortices are loops and they affect
the same disordering in the phase having large loops.

</DOC>
<DOC>
<DOCNO> 120824 </DOCNO>
Searching for MACHOs in Galaxy Clusters


  If cluster dark matter is in the form of compact objects it will introduce
fluctuations into the light curves of distant sources. Current searches for
MACHOs in clusters of galaxies focus on monitoring quasars behind nearby
systems. This paper considers the effect of such a compact population on the
surface brightness distribution of giant gravitationally lensed arcs. As the
microlensing optical depth is significant in these clusters, the expected
fluctuations are substantial and are observable. Focusing on the giant arc seen
in Abell 370, we demonstrate that several `extreme' events would be visible in
a comparison of HST observations at two epochs. Utilizing NGST, long term
monitoring should reveal a ubiquitous twinkling of brightness over the surface
of the arcs.

</DOC>
<DOC>
<DOCNO> 121198 </DOCNO>
Chandra High-Resolution Camera Observations of the Luminous X-Ray Source


  We have analyzed Chandra High Resolution Camera observations of the starburst
galaxy M82, concentrating on the most luminous x-ray source. We find a position
for the source of $\rm R.A. = 09^h 55^m 50^s.2, decl. = +69^{\circ} 40\arcmin
46\arcsec.7$ (J2000) with a $1\sigma$ radial error of $0.7\arcsec$. The
accurate x-ray position shows that the luminous source is not at the dynamical
centre of M82 nor coincident with any suggested radio AGN candidate. The source
is highly variable between observations, which suggests that the source is a
compact object and not a supernova or remnant. There is no significant short
term variability within the observations. Dynamical friction and the off-center
position place an upper bound of $10^{5} - 10^{6} M_{\odot}$ on the mass of the
object, depending on its age. The x-ray luminosity suggests a compact object
mass of at least $500 M_{\odot}$. Thus, the luminous source in M82 may
represent a new class of compact object with a mass intermediate between those
of stellar mass black hole candidates and supermassive black holes.

</DOC>
<DOC>
<DOCNO> 119311 </DOCNO>
Pulsars in the Westerbork Northern Sky Survey


  I have searched the Westerbork Northern Sky Survey (WENSS) source list for
detections of known radio pulsars. A source with a flux density greater than
five times the local noise level is found near the positions of 25 pulsars. The
probability that one out of these 25 sources is a chance coincidence is about
10%. I have looked at the WENSS maps of the non-detected pulsars. A flux
density between three and five times the local noise level is found near the
positions of 14 of these non-detected pulsars. There is a 50 percent
probability that (at least) one of these marginal detections is just a noise
fluctuation. Fourteen radio pulsars, which according to earlier flux
measurements have flux densities above three times the WENSS noise level, are
not detected. Of the 39 pulsars detected in the WENSS 19 are also detected in
the NRAO VLA Sky Survey (NVSS). By combining the WENSS and NVSS flux densities
for these 19 pulsars spectral indices are obtained that differ by up to 50%
from the long term averaged values reported in the literature. This affects the
reliability of pulsar candidates that are selected on the basis of their
WENSS-NVSS spectral index.

</DOC>
<DOC>
<DOCNO> 102140 </DOCNO>
Distribution of Values of Real Quadratic Zeta Functions


  The author has previously extended the theory of regular and irregular primes
to the setting of arbitrary totally real number fields. It has been conjectured
that the Bernoulli numbers, or alternatively the values of the Riemann zeta
function at odd negative integers, are evenly distributed modulo p for every p.
This is the basis of a well-known heuristic, given by Siegel, for estimating
the frequency of irregular primes. So far, analyses have shown that if
Q(\sqrt{D}) is a real quadratic field, then the values of the zeta function
\zeta_{D}(1-2m)=\zeta_{Q(\sqrt{D})}(1-2m) at negative odd integers are also
distributed as expected modulo p for any p. However, it has proven to be very
computationally intensive to calculate these numbers for large values of m. In
this paper, we present the alternative of computing \zeta_{D}(1-2m) for a fixed
value of D and a large number of different m.

</DOC>
<DOC>
<DOCNO> 83310 </DOCNO>
A Moment of Perfect Clarity I: The Parallel Census Technique


  We discuss the history and uses of the parallel census technique---an elegant
tool in the study of certain computational objects having polynomially bounded
census functions. A sequel will discuss advances (including Cai, Naik, and
Sivakumar [CNS95] and Glasser [Gla00]), some related to the parallel census
technique and some due to other approaches, in the complexity-class collapses
that follow if NP has sparse hard sets under reductions weaker than (full)
truth-table reductions.

</DOC>
<DOC>
<DOCNO> 102669 </DOCNO>
To what extent do the Classical Equations of Motion Determine the


  A simple example of one particle moving in a (1+1) space-time is considered.
As an example we take the harmonic oscillator. We confirm the statement that
the classical Equations of Motion do not determine at all the quantization
scheme. To this aim we use two inequivalent Lagrange functions, yielding
Euler-Lagrange Equations, having the same set of solutions. We present in
detail the calculations of both cases to emphasize the differences occuring
between them.

</DOC>
<DOC>
<DOCNO> 120214 </DOCNO>
Young Circumstellar Disks Near Evolved Massive Stars and Supernovae


  There is increasing evidence that low mass stars with circumstellar disks can
be born close to massive stars, in some cases within tenths of a pc. If the
disks have lifetimes greater than those of the more massive stars, they are
exposed to the radiation fields and gas flows from the late evolutionary phases
and supernovae of the massive stars. The fast flows from supernovae are likely
to give some stripping of mass from the disks, but do not typically lead to
complete disruption of the disks. In the slow wind from a red supergiant star,
there is the possibility of gravitational accretion of wind matter onto the
circumstellar disk. In the supernova explosion of a red supergiant, the
radiative flux at the time of shock breakout can heat and ionize a nearby disk,
leading to transient, narrow line emission. There are consequences for the
solar nebula if it was born ~0.2 pc from a massive star that became a red
supergiant. Accretion from the wind could supply a substantial amount of 26Al
to the disk. The high radiative luminosity of the eventual supernova could lead
to the melting of dust grains and the formation of chondrules. The passage of
the supernova ejecta could drive a shock wave in the disk, heating it.

</DOC>
<DOC>
<DOCNO> 120583 </DOCNO>
Asymmetric Beams in Cosmic Microwave Background Anisotropy Experiments


  We propose a new formalism to handle asymmetric beams in the data analysis of
cosmic microwave background anisotropy experiments. For any beam shape, the
formalism finds the optimal circularly symmetric equivalent and is thus easily
adaptable to existing data analysis methods. We demonstrate certain key points
by using a simulated highly elliptic beam, and the beams and data of the
MAXIMA-1 experiment, where the asymmetry is mild. In particular, we show that
in both cases the formalism does not bias the angular power spectrum estimates.
We analyze the limitations of the formalism and find that it is well suited for
most practical situations.

</DOC>
<DOC>
<DOCNO> 12908 </DOCNO>
Comment on ``Quantum Phase Transition of the Randomly Diluted Heisenberg


  In Phys. Rev. Lett. 84, 4204 (2000) (cond-mat/9905379), Kato et al. presented
quantum Monte Carlo results indicating that the critical concentration of
random non-magnetic sites in the two-dimensional antiferromagnetic Heisenberg
model equals the classical percolation density; pc=0.407254. The data also
suggested a surprising dependence of the critical exponents on the spin S of
the magnetic sites, with a gradual approach to the classical percolation
exponents as S goes to infinity. I here argue that the exponents in fact are
S-independent and equal to those of classical percolation. The apparent
S-dependent behavior found by Kato et al. is due to temperature effects in the
simulations as well as a quantum effect that masks the true asymptotic scaling
behavior for small lattices.

</DOC>
<DOC>
<DOCNO> 118568 </DOCNO>
Using HI to probe large scale structures at z ~ 3


  The redshifted 1420 MHz emission from the HI in unresolved damped
Lyman-\alpha clouds at high z will appear as a background radiation in low
frequency radio observations. This holds the possibility of a new tool for
studying the universe at high-z, using the mean brightness temperature to probe
the HI content and its fluctuations to probe the power spectrum. Existing
estimates of the HI density at z~3 imply a mean brightness temperature of 1 mK
at 320 Mhz. The cross-correlation between the temperature fluctuations across
different frequencies and sight lines is predicted to vary from 10^{-7} K^2 to
10^{-8} K^2 over intervals corresponding to spatial scales from 10 Mpc to 40
Mpc for some of the currently favoured cosmological models. Comparing this with
the expected sensitivity of the GMRT, we find that this can be detected with
\~10 hrs of integration, provided we can distinguish it from the galactic and
extragalactic foregrounds which will swamp this signal. We discuss a strategy
based on the very distinct spectral properties of the foregrounds as against
the HI emission, possibly allowing the removal of the foregrounds from the
observed maps.

</DOC>
<DOC>
<DOCNO> 122630 </DOCNO>
Star Forming Objects in the Tidal Tails of Compact Groups


  A search for star forming objects belonging to tidal tails has been carried
out in a sample of deep Halpha images of 16 compact groups of galaxies. A total
of 36 objects with Halpha luminosity larger than 10^38 erg s-1 have been
detected in five groups. The fraction of the total Halpha luminosity of their
respective parent galaxies shown by the tidal objects is always below 5% except
for the tidal features of HCG95, whose Halpha luminosity amounts to 65% of the
total luminosity. Out of this 36 objects, 9 star forming tidal dwarf galaxy
candidates have been finally identified on the basis of their projected
distances to the nuclei of the parent galaxies and their total Halpha
luminosities. Overall, the observed properties of the candidates resemble those
previously reported for the so-called tidal dwarf galaxies.

</DOC>
<DOC>
<DOCNO> 13542 </DOCNO>
Thermodynamics of osp(1|2) Integrable Spin Chain: Finite Size Correction


  This note is a supplement to our previous papers: Mod. Phys. Lett. A14 (1999)
2427 (math-ph/9911010); Int. J. Mod. Phys. A15 (2000) 2329 (math-ph/9912014).
The thermodynamic Bethe ansatz (TBA) equation for an integrable spin chain
related to the Lie superalgebra osp(1|2) is analyzed. The central charge
determined by low temperature asymptotics of the specific heat can be expressed
by the Rogers dilogarithmic function, and identified to be 1. Solving the TBA
equation numerically, we evaluate the several thermodynamic quantities. The
excited state TBA equation is also discussed.

</DOC>
<DOC>
<DOCNO> 101184 </DOCNO>
Twisted vertex representations via spin groups and the McKay


  We establish a twisted analog of our recent work on vertex representations
and the McKay correspondence. For each finite group $\Gamma$ and a virtual
character of $\Gamma$ we construct twisted vertex operators on the Fock space
spanned by the super spin characters of the spin wreath products
$\Gamma\wr\widetilde{S}_n$ of $\Gamma$ and a double cover of the symmetric
group $S_n$ for all $n$. When $\Gamma$ is a subgroup of $SL_2(\mathbb C)$ with
the McKay virtual character, our construction gives a group theoretic
realization of the basic representations of the twisted affine and twisted
toroidal algebras. When $\Gamma$ is an arbitrary finite group and the virtual
character is trivial, our vertex operator construction yields the spin
character tables for $\Gamma\wr\widetilde{S}_n$.

</DOC>
<DOC>
<DOCNO> 121745 </DOCNO>
Australian Cosmic Ray Modulation Research


  Australian research into variations of the cosmic ray flux arriving at the
Earth has played a pivotal role for more than 50 years. The work has been
largely led by the groups from the University of Tasmania and the Australian
Antarctic Division and has involved the operation of neutron monitors and muon
telescopes from many sites. In this paper the achievements of the Australian
researchers are reviewed and future experiments are described. Particular
highlights include: the determination of cosmic ray modulation parameters; the
development of modelling techniques of Ground Level Enhancements; the
confirmation of the Tail-In and Loss-Cone Sidereal anisotropies; the Space Ship
Earth collaboration; and the Solar Cycle latitude survey.

</DOC>
<DOC>
<DOCNO> 71293 </DOCNO>
Weak Interactions of Light Flavours


  An overview is given of weak interaction physics of the light flavours. It
starts with the definition of the CKM matrix and the measurement of its
components in the light-flavour sector via semi-leptonic decays. The main part
of the lectures is devoted to non-leptonic decays with a main emphasis on
analytical calculations of $K\to\pi\pi$ and $K^0\leftrightarrow \kob$ mixing.
It finishes with an overview of Chiral Perturbation Theory in $K\to3\pi$ and of
rare Kaon decays.

</DOC>
<DOC>
<DOCNO> 84245 </DOCNO>
Statistical mechanics of generally covariant quantum theories: A


  We study the possibility of applying statistical mechanics to generally
covariant quantum theories with a vanishing Hamiltonian. We show that (under
certain appropiate conditions) this makes sense, in spite of the absence of a
notion of energy and external time. We consider a composite system formed by a
large number of identical components, and apply Boltzmann's ideas and the
fundamental postulates of ordinary statistical physics. The thermodynamical
parameters are determined by the properties of the thermalizing interaction. We
apply these ideas to a simple example, in which the component system has one
physical degree of freedom and mimics the constraint algebra of general
relativity.

</DOC>
<DOC>
<DOCNO> 71457 </DOCNO>
Decay-lepton angular distributions in e+e- -> t tbar to O(alpha_s) in


  Order-alpha_s QCD corrections in the soft-gluon approximation to angular
distributions of decay charged leptons in the process e+e- -> t tbar, followed
by semileptonic decay of t or tbar, are obtained in the e+e- centre-of-mass
frame. As compared to distributions in the top rest frame, these have the
advantage that they would allow direct comparison with experiment without the
need to reconstruct the top rest frame or a spin quantization axis. Analytic
expressions for the distribution in the charged-lepton polar angle and triple
distribution in the polar angle of t and polar and azimuthal angles of the
lepton are obtained. Numerical values are discussed for total c.m. energies of
400 GeV and 800 GeV.

</DOC>
<DOC>
<DOCNO> 121040 </DOCNO>
Constraints on Galaxy Density Profiles from Strong Gravitational


  We consider a wide range of parametric mass models for B 1933+503, a
ten-image radio lens, and identify shared properties of the models with the
best fits. The approximate rotation curves varies by less than 8.5% from the
average value between the innermost and the outermost image (1.5h^{-1} kpc to
4.1h^{-1} kpc) for models within 1 \sigma of the best fit, and the radial
dependence of the shear strength and angle also have common behavior for the
best models. The time delay between images 1 and 6, the longest delay between
the radio cores, is \Delta t = (10.6^{+2.4}_{-1.1})h^{-1} days (\Omega_0=0.3,
\lambda_0=0.7) including all the modeling uncertainties. Deeper infrared
observations, to more precisely register the lens galaxy with the radio images
and to measure the properties of the Einstein ring image of the radio source's
host galaxy, would significantly improve the model constraints and further
reduce the uncertainties in the mass distribution and time delay.

</DOC>
<DOC>
<DOCNO> 100591 </DOCNO>
On the consistency of the definable tree property on \aleph_1


  In this paper we prove the equiconsistency of ``Every omega_1 tree which is
first order definable over H_{omega_1} has a cofinal branch'' with the
existence of a Pi^1_1 reflecting cardinal. The proof uses a definable version
of Ramsey theorem on aleph_1 which is again equiconsistent with a Pi^1_1
reflecting cardinal. We also prove that the addition of $MA$ to the definable
tree property increases the consistency strength to that of a weakly compact
cardinal. Finally we comment on the generalization to higher cardinals.

</DOC>
<DOC>
<DOCNO> 80799 </DOCNO>
QCD in a finite box: Numerical test studies in the three


  The Leutwyler-Smilga prediction regarding the (ir)relevance of the global
topological charge for QCD in a finite box is subject to a test. To this end
the lattice version of a suitably chosen analogue (massive 2-flavour Schwinger
model) is analyzed in the small ($V\Sigma m \ll 1$), intermediate ($V\Sigma m
\simeq 1$) and large ($V\Sigma m \gg 1$) Leutwyler-Smilga regimes. The
predictions for the small and large regimes are confirmed and illustrated. New
results about the role of the functional determinant in all three regimes and
about the sensitivity of physical observables on the topological charge in the
intermediate regime are presented.

</DOC>
<DOC>
<DOCNO> 69787 </DOCNO>
Toward a Symmetrization of Gravity I. Classical Formulation: Results and


  We propose an additional term in the classical gravitational force law, which
is repelling in nature, and which may solve the dark matter problem. As an
inverse cube field interaction, it operates over 4 real spatial dimensions and
its effect on our observable 3-D space may account both for flat rotation
curves and standard Newtonian dynamics at small radial distances. By utilizing
cosmological clustering scales, we can derive the universal interaction
strength, and show that this naturally leads to an altered Planck mass that
becomes the neutron/proton rest mass. Moreover, the correct value for the
electron rest mass can be predicted using only classical electrostatics coupled
with the current theory. On cosmological scales, the interaction easily
accounts for the acceleration of the Hubble flow.

</DOC>
<DOC>
<DOCNO> 9442 </DOCNO>
The QCD phase transition in the inhomogeneous Universe


  We investigate a new mechanism for the cosmological QCD phase transition:
inhomogeneous nucleation. The primordial temperature fluctuations, measured to
be $\delta T/T \sim 10^{-5}$, are larger than the tiny temperature interval, in
which bubbles would form in the standard picture of homogeneous nucleation.
Thus the bubbles nucleate at cold spots. We find the typical distance between
bubble centers to be a few meters. This exceeds the estimates from homogeneous
nucleation by two orders of magnitude. The resulting baryon inhomogeneities may
affect primordial nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 40442 </DOCNO>
Introduction and recent developments in gamma-gamma, gamma-electron


  High energy photon colliders (gamma-gamma, gamma-electron) based on backward
Compton scattering of laser light is a very natural addition to e+e- linear
colliders. In this report we consider mainly this option for the TESLA project.
Recent study has shown that the horizontal emittance in the TESLA damping ring
can be further decreased by a factor of four. In this case the gamma-gamma
luminosity luminosity in the high energy part of spectrum can reach 0.3--0.5
L_e+e-. Typical cross sections of interesting processes in gamma-gamma
collisions are higher than those in e+e- collisions by about one order of
magnitude, so the number of events in gamma-gamma collisions will be more that
in e+e- collisions. The key new element in photon colliders is a very powerful
laser system. The most straightforward solution is ``an optical storage ring
(optical trap)'' with diode pumped laser injector which is today technically
feasible. This paper briefly review the status of a photon collider based at
TESLA, its possible parameters.

</DOC>
<DOC>
<DOCNO> 11253 </DOCNO>
Wetting transitions of He4 on alkali metal surfaces from density


  We have studied the wetting properties of He4 adsorbed on the surface of
heavy alkali metals by using a non-local free-energy density-functional which
describes accurately the surface properties of liquid He4 in the temperature
range 0<T<3 K.Our results for He4 on the Cs surface give both the temperature
dependence of the contact angle and the wetting temperature in good agreement
with the experimental findings. For the He/Rb system we find that a wetting
transition on the Rb surface occurs at T=1.4 K, whereas the experiments show
either wetting down to T=0 or a wetting transition at T=0.3 K. We suggest that
this disagreement is due either to an inaccuracy of the fluid-substrate
potential used in our calculations or the consequence of substrate roughness,
which is known to affect the Rb surface, and whose effect would be to lower the
wetting temperature. The sensitivity of the wetting transition to the
He-surface potential are stressed for the He/Rb surface, which may justify the
controversial experimental findings for this system.

</DOC>
<DOC>
<DOCNO> 151922 </DOCNO>
A Five-brane Modulus in the Effective N=1 Supergravity of M-Theory


  Five-branes lead in four dimensions to massless N=1 supermultiplets if
M-theory is compactified on S1/Z2 x (a Calabi-Yau threefold). One of them
describes the modulus associated with the position of the five-brane along the
circle S1. We derive the effective four-dimensional supergravity of this
multiplet and its coupling to bulk moduli and to Yang-Mills and charged matter
multiplets located on Z2 fixed planes. The dynamics of the five-brane modes is
obtained by reduction and supersymmetrization of the covariant five-brane
bosonic action. Our construction respects all symmetries of M-theory, including
the self-duality of the brane antisymmetric tensor. Corrections to gauge
couplings are strongly constrained by this self-duality property. The brane
contribution to the effective scalar potential is formally similar to a
renormalization of the dilaton. The vacuum structure is not modified.
Altogether, the impact of the five-brane modulus on the effective supergravity
is reminiscent of string one-loop corrections produced by standard
compactification moduli.

</DOC>
<DOC>
<DOCNO> 100778 </DOCNO>
Coherent Bicartesian and Sesquicartesian Categories


  Sesquicartesian categories are categories with nonempty finite products and
arbitrary finite sums, including the empty sum. Coherence is here demonstrated
for sesquicartesian categories in which the first and the second projection
from the product of the initial object with itself are the same. (The category
Set is such a category.) This coherence amounts to the existence of a faithful
functor from free categories of this sort, generated by objects, to the
category of relations on finite ordinals. Coherence also holds for bicartesian
categories where, in addition to this equality for projections, we have that
the first and the second injection to the sum of the terminal object with
itself are the same.

</DOC>
<DOC>
<DOCNO> 11603 </DOCNO>
A simple variational approach to the quantum Frenkel-Kontorova model


  We present a simple and complete variational approach to the one-dimensional
quantum Frenkel-Kontorova model. Dirac's time-dependent variational principle
is adopted together with a Hatree-type many-body trial wavefunction for the
atoms. The single-particle state is assumed to have the Jackiw-Kerman form. We
obtain an effective classical Hamiltonian for the system which is simple enough
for a complete numerical solution for the static ground state of the model.
Numerical results show that our simple approach captures the essence of the
quantum effects first observed in quantum Monte Carlo studies.

</DOC>
<DOC>
<DOCNO> 67878 </DOCNO>
A Phenomenological Description of (\pi^{-}\Delta^{++}) Photo- and


  The (\pi^{-}\Delta^{++}) production on the nucleon by real and virtual
photons is discussed as initial step in a simple model approach for the two
pion photo- and electroproduction on the nucleon, with emphasis on nucleon
resonance excitation which is of interest for new facilities like TJNAF. A
calculation for (\pi^{-}\Delta^{++}) channel in resonance excitation region is
presented and compared to existing experimental data along with a discussion of
physical effects that we find to be of relevance. The calculation is proposed
as a starting basis for the investigation of (N^{*}) electromagnetic form
factors using experimental data about two pion production by real and virtual
photons.

</DOC>
<DOC>
<DOCNO> 80951 </DOCNO>
N* Spectrum using an O(a)-Improved Fermion Action


  The construction of operators and calculational methods for the determination
of the N* spectrum are discussed. The masses of the parity partners of the
nucleon and delta are computed from the O(a)-improved data of the UKQCD
Collaboration, and a clear splitting observed between the mass of the nucleon
and its parity partner.

</DOC>
<DOC>
<DOCNO> 102608 </DOCNO>
A uniqueness theorem for stable homotopy theory


  In this paper we study the global structure of the stable homotopy theory of
spectra. We establish criteria for when the homotopy theory associated to a
given stable model category agrees with the classical stable homotopy theory of
spectra. One sufficient condition is that the associated homotopy category is
equivalent to the stable homotopy category as a triangulated category with an
action of the ring of stable homotopy groups of spheres. In other words, the
classical stable homotopy theory, with all of its higher order information, is
determined by the homotopy category as a triangulated category with an action
of the stable homotopy groups of spheres. Another sufficient condition is the
existence of a small generating object (corresponding to the sphere spectrum)
for which a specific `unit map' from the infinite loop space QS^0 to the
endomorphism space is a weak equivalence.

</DOC>
<DOC>
<DOCNO> 121792 </DOCNO>
Parent Stars of Extrasolar Planets VI: Abundance Analyses of 20 New


  The results of new spectroscopic analyses of 20 recently reported extrasolar
planet parent stars are presented. The companion of one of these stars, HD
10697, has recently been shown to have a mass in the brown dwarf regime; we
find [Fe/H] $= +0.16$ for it. For the remaining sample, we derive [Fe/H]
estimates ranging from -0.41 to $+0.37$, with an average value of $+0.18 \pm
0.19$. If we add the 13 stars included in the previous papers of this series
and 6 other stars with companions below the 11 M$_{\rm Jup}$ limit from the
recent studies of Santos et al., we derive $<$[Fe/H]$> = +0.17 \pm 0.20$.
  Among the youngest stars with planets with F or G0 spectral types, [Fe/H] is
systematically larger than young field stars of the same Galactocentric
distance by 0.15 to 0.20 dex. This confirms the recent finding of Laughlin that
the most massive stars with planets are systematically more metal rich than
field stars of the same mass. We interpret these trends as supporting a
scenario in which these stars accreted high-Z material after their convective
envelopes shrunk to near their present masses. Correcting these young star
metallicities by 0.15 dex still does not fully account for the difference in
mean metallicity between the field stars and the full parent stars sample.
  The stars with planets appear to have smaller [Na/Fe], [Mg/Fe], and [Al/Fe]
values than field dwarfs of the same [Fe/H]. They do not appear to have
significantly different values of [O/Fe], [Si/Fe], [Ca/Fe], or [Ti/Fe], though.

</DOC>
<DOC>
<DOCNO> 101667 </DOCNO>
Boundedness and surjectivity in Banach spaces


  We define the ($w^\ast$-) boundedness property and the ($w^\ast$-)
surjectivity property for sets in normed spaces. We show that these properties
are pairwise equivalent in complete normed spaces by characterizing them in
terms of a category-like property called ($w^\ast$-) thickness. We give
examples of interesting sets having or not having these properties. In
particular, we prove that the tensor product of two $w^\ast$-thick sets in
$\Xastast$ and $\Yast$ is a $w^\ast$-thick subset in $L(X,Y)^\ast$ and obtain
as a concequense that the set $w^\ast -exp\:B_{K(l_2)^\ast}$ is $w^\ast$-thick.

</DOC>
<DOC>
<DOCNO> 117688 </DOCNO>
Evolution of the cluster X-ray luminosity function from the WARPS survey


  The evolution of the X-ray luminosity function of clusters of galaxies has
been measured to z=0.85 using over 150 X-ray selected clusters found in the
WARPS survey. We find no evidence for evolution of the luminosity function at
any luminosity or redshift. The observations constrain the evolution of the
space density of moderate luminosity clusters to be very small, and much less
than predicted by most models of the growth of structure with Omega=1.

</DOC>
<DOC>
<DOCNO> 118130 </DOCNO>
The Cosmic Microwave Background Radiation


  We summarize the theoretical and observational status of the study of the
Cosmic Microwave Background radiation. Its thermodynamic spectrum is a robust
prediction of the Hot Big Bang cosmology and has been confirmed
observationally. There are now 76 observations of Cosmic Microwave Background
anisotropy, which we present in a table with references. We discuss the
theoretical origins of these anisotropies and explain the standard jargon
associated with their observation.

</DOC>
<DOC>
<DOCNO> 13855 </DOCNO>
Comment on "Like-Charge Attraction and Hydrodynamic Interaction"


  Comment on T. M. Squires and M. P. Brenner, Phys.Rev.Lett. 85, 4976 (2000)

</DOC>
<DOC>
<DOCNO> 84639 </DOCNO>
Comment on "Formation of primordial black holes by cosmic strings"


  We show that in a pioneering paper by Polnarev and Zembowicz, some
conclusions concerning the characteristics of the Turok-strings are generally
not correct. In addition we show that the probability of string collapse given
there, is off by a large prefactor (~1000).

</DOC>
<DOC>
<DOCNO> 117577 </DOCNO>
The giant X-ray outbursts from nearby, non-active galaxies: tidal


  One efficient method to probe the direct vicinity of SMBHs in nearby galaxies
is to make use of the detection of flares from tidally disrupted stars (e.g.,
Lidskii & Ozernoi 1979, Rees 1988). The first few excellent candidates for the
occurrence of this process in non-active galaxies have emerged recently. Here,
we present a review of these observations, compare with variability in AGN, and
discuss theoretical implications. We concentrate on the cases of NGC 5905 and
RXJ1242-1119, and report results from a systematic search for further X-ray
flares from a sample of >100 nearby galaxies.

</DOC>
<DOC>
<DOCNO> 84288 </DOCNO>
Normal modes of relativistic systems in post-Newtonian approximation and


  In part I, we use the post-Newtonian (pn) order of Liouville's equation to
study the normal modes of oscillation of a spherically symmetric relativistic
system. Perturbations that are neutral in Newtonian approximation develop into
a new sequence of normal modes.
  In part II, stability curve of r-modes of neutron stars are calculated by
considering vorticity-shear viscosity coupling.
  As an application, the loss of angular momentum through gravitational
radiation, driven by the excitation of r-modes, is considered in neutron stars
having rotation frequencies smaller than the associated critical frequency.

</DOC>
<DOC>
<DOCNO> 117724 </DOCNO>
Microjansky radio sources in DC0107-46 (Abell 2877)


  The cluster DC0107-46 (Abell 2877) lies within the Phoenix Deep Survey, made
at 1.4 GHz with the Australia Telescope Compact Array. Of 89 known optical
cluster members, 70 lie within the radio survey area. Of these 70 galaxies, 15
(21%) are detected, with luminosities as faint as 10^20 W/Hz. Spectroscopic
observations are available for 14/15 of the radio-detected cluster galaxies.
Six galaxies show only absorption features and are typical low-luminosity AGN
radio sources. One galaxy hosts a Seyfert 2 nucleus, two are star-forming
galaxies, and the remaining five may be star-forming galaxies, AGNs, or both.

</DOC>
<DOC>
<DOCNO> 118783 </DOCNO>
Rotation, mass loss and pulsations of the star: an analytical model


  The characteristics of the star with the "prescribed" density distribution
$\rho=\rho_c[1-(r/R)^\alpha]$ are analytically studied.

</DOC>
<DOC>
<DOCNO> 72080 </DOCNO>
Violations of Lorentz Covariance in Light Front Quark Models


  Electromagnetic form factors of the nucleon from relativistic quark models
are analyzed: results from null-plane projection of the Feynman triangle
diagram are compared with a Bakamjian-Thomas model. The magnetic form factors
of the models differ by about 15% at spacelike momentum transfer 0.5 GeV^2,
while the charge form factors are much closer. Spurious contributions to
electromagnetic form factors due to violations of rotational symmetry are
eliminated from both models. One method changes magnetic form factors by about
10%, whereas the charge form factors stay nearly the same. Another one changes
the charge form factor of the Bakamjian-Thomas model by more than 50%.

</DOC>
<DOC>
<DOCNO> 118673 </DOCNO>
Calibration of Nebular Emission-line Diagnostics: II. Abundances


  (Abridged) We examine standard methods of measuring nebular chemical
abundances, including estimates based on direct T_e measurements, and also
bright-line diagnostics. We use observations of 4 LMC HII regions whose
ionizing stars have classifications ranging from O7 to WN3. We assume a 2-zone
T_e structure to compute ionic abundances. We compare with photoionization
models tailored to the properties of the individual objects, and emphasize the
importance of correctly relating T_e in the two zones, which can otherwise
cause errors of ~0.2 dex in abundance estimates. There are no spatial
variations to within 0.1 - 0.15 dex in any of the objects, even one hosting 3
WR stars.
  Our data agree with the modeled R23 and S23 diagnostics of O and S. We
present the first theoretical tracks for S23, which are in excellent agreement
with a larger dataset. However, contrary to earlier suggestions, S23 is much
more sensitive to the ionization parameter than is R23, because S23 does not
sample S IV. We therefore introduce S234 = ([SII]+[SIII]+[SIV])/H-beta.
Predicted and observed spatial variations in S234 are dramatically reduced in
contrast to S23. The intensity of [SIV]10.5 microns is easily estimated from a
simple relation between [SIV]/[SIII] and [OIII]/[OII]. This method of
estimating S234 yields excellent agreement with our models, hence we give a
theoretical calibration for S234. The double-valued structure of S23 and S234
remains an important problem as for R23, and presently we consider the S
diagnostics reliable only at Z < 0.5 Z_sol. However, the slightly larger
dynamic range and excellent compatibility with theoretical predictions suggest
the S diagnostics to be more effective abundance indicators than R23.

</DOC>
<DOC>
<DOCNO> 121046 </DOCNO>
Composite Spectra from the FIRST Bright Quasar Survey


  We present a very high signal-to-noise ratio composite spectrum created using
657 radio-selected quasars from the FIRST Bright Quasar Survey. The spectrum
spans rest-frame wavelengths 900 - 7500 Angstroms. Additionally we present
composite spectra formed from subsets of the total data set in order to
investigate the spectral dependence on radio loudness and the presence of broad
absorption. In particular, radio-loud quasars are red compared to radio-quiet
quasars, and quasars showing low-ionization broad absorption lines are red
compared to other quasars. We compare our composites with those from the Large
Bright Quasar Survey. Composite quasar spectra have proven to be valuable tools
for a host of applications, and in that spirit we make these publically
available via the FIRST survey web page.

</DOC>
<DOC>
<DOCNO> 169623 </DOCNO>
Dark-State Polaritons in Electromagnetically Induced Transparency


  We identify form-stable coupled excitations of light and matter (``dark-state
polaritons'') associated with the propagation of quantum fields in
Electromagnetically Induced Transparency. The properties of the dark-state
polaritons such as the group velocity are determined by the mixing angle
between light and matter components and can be controlled by an external
coherent field as the pulse propagates. In particular, light pulses can be
decelerated and ``trapped'' in which case their shape and quantum state are
mapped onto metastable collective states of matter. Possible applications of
this reversible coherent-control technique are discussed.

</DOC>
<DOC>
<DOCNO> 10992 </DOCNO>
Novel criticality in a model with absorbing states


  We study a one-dimensional model which undergoes a transition between an
active and an absorbing phase. Monte Carlo simulations supported by some
additional arguments prompted as to predict the exact location of the critical
point and critical exponents in this model. The exponents $\delta=0.5$ and
$z=2$ follows from random-walk-type arguments. The exponents $\beta =
\nu_{\perp}$ are found to be non-universal and encoded in the singular part of
reactivation probability, as recently discussed by H. Hinrichsen
(cond-mat/0008179). A related model with quenched randomness is also studied.

</DOC>
<DOC>
<DOCNO> 151293 </DOCNO>
Reminiscences


  Reminiscences of Bunji Sakita.

</DOC>
<DOC>
<DOCNO> 120865 </DOCNO>
The Disk and Dark Halo Mass of the Barred Galaxy NGC 4123. I.


  The non-circular streaming motions in barred galaxies are sensitive to the
mass of the bar and can be used to lift the degeneracy between disk and dark
matter halo encountered when fitting axisymmetric rotation curves of disk
galaxies. In this paper, we present photometric and kinematic observations of
NGC 4123, a barred galaxy of modest size (V_rot = 130 km/sec, L = 0.7 L_*),
which reveal strong non-circular motions. The bar has straight dust lanes and
an inner Lindblad resonance. The disk of NGC 4123 has no sign of truncation out
to 10 scale lengths, and star-forming regions are found well outside R_25. A
Fabry-Perot H-alpha velocity field shows velocity jumps of >100 km/sec at the
location of the dust lanes within the bar, indicating shocks in the gas flow.
VLA observations yield the velocity field of the H I disk. Axisymmetric mass
models yield good fits to the rotation curve outside the bar regionfor disk
I-band M/L of 2.25 or less, and dark halos with either isothermal or power-law
profiles can fit the data well. In a companion paper, we model the full 2-D
velocity field, including non-circular motions, to determine the stellar M/L
and the mass of the dark halo.

</DOC>
<DOC>
<DOCNO> 120394 </DOCNO>
A Kinematic Model for the Narrow-Line Region in NGC 4151


  We present a simple kinematic model for the narrow-line region (NLR) of the
Seyfert 1 galaxy NGC 4151, based on our previous observations of extended [O
III] emission with the Space Telescope Imaging Spectrograph (STIS). The model
is similar to a biconical radial outflow model developed for the Seyfert 2
galaxy NGC 1068, except that the bicone axis is tilted much more into our line
of sight (40 degrees out of the plane of the sky instead of 5 degrees), and the
maximum space velocities are lower (750 km/s instead of 1300 km/s. We find
evidence for radial acceleration of the emission-line knots to a distance of
160 pc, followed by deceleration that approaches the systemic velocity at a
distance of 290 pc (for a distance to NGC 4151 of 13.3 Mpc). Other similarities
to the kinematics of NGC 1068 are: 1) there are a number of high-velocity
clouds that are not decelerated, suggesting that the medium responsible for the
deceleration is patchy, and 2) the bicone in NGC 4151 is at least partially
evacuated along its axis. Together, these two Seyfert galaxies provide strong
evidence for radial outflow (e.g., due to radiation and/or wind pressure) and
against gravitational motion or expansion away from the radio jets as the
principal kinematic component in the NLR.

</DOC>
<DOC>
<DOCNO> 10582 </DOCNO>
Novel Electrostatic Attraction from Plasmon Fluctuations


  In this Letter, we show that at low temperatures, zero-point fluctuations of
the plasmon modes of two mutually coupled 2-D planar Wigner crystals give rise
to a novel long-range attractive force. For the case where the distance $d$
between two planar surfaces is large, this attractive force has an unusual
power-law decay, which scales as $d^{-7/2},$ unlike other fluctuation-induced
forces. Specifically, we note that its range is longer than the ``standard''
zero-temperature van der Waals interaction. This result may in principle be
observed in bilayer electronic systems and provides insight into the nature of
correlation effects for highly charged surfaces.

</DOC>
<DOC>
<DOCNO> 9337 </DOCNO>
Effects of uniaxial strain in LaMnO_3


  The effects of uniaxial strain on the structural, orbital, optical, and
magnetic properties of LaMnO_3 are calculated using a general elastic energy
expression, along with a tight-binding parameterization of the band theory.
Tensile uniaxial strain of the order of 2 % (i.e., of the order of magnitude of
those induced in thin films by lattice mismatch with substrates) is found to
lead to changes in the magnetic ground state, leading to dramatic changes in
the band structure and optical conductivity spectrum. The magnetostriction
effect associated with the Neel transition of bulk(unstrained) LaMnO_3 is also
determined. Due to the Jahn-Teller coupling, the uniform tetragonal distortion
mode is softer in LaMnO_3 than in doped cubic manganates. Reasons why the
observed (\pi \pi 0) orbital ordering is favored over a (\pi \pi \pi)
periodicity are discussed.

</DOC>
<DOC>
<DOCNO> 84941 </DOCNO>
Hyperbolic formulations and numerical relativity II: Asymptotically


  We study asymptotically constrained systems for numerical integration of the
Einstein equations, which are intended to be robust against perturbative errors
for the free evolution of the initial data. First, we examine the previously
proposed "$\lambda$-system", which introduces artificial flows to constraint
surfaces based on the symmetric hyperbolic formulation. We show that this
system works as expected for the wave propagation problem in the Maxwell system
and in general relativity using Ashtekar's connection formulation. Second, we
propose a new mechanism to control the stability, which we call the ``adjusted
system". This is simply obtained by adding constraint terms in the dynamical
equations and adjusting its multipliers. We explain why a particular choice of
multiplier reduces the numerical errors from non-positive or pure-imaginary
eigenvalues of the adjusted constraint propagation equations. This ``adjusted
system" is also tested in the Maxwell system and in the Ashtekar's system. This
mechanism affects more than the system's symmetric hyperbolicity.

</DOC>
<DOC>
<DOCNO> 83367 </DOCNO>
Probabilistic Constraint Logic Programming. Formal Foundations of


  In this thesis, we present two approaches to a rigorous mathematical and
algorithmic foundation of quantitative and statistical inference in
constraint-based natural language processing. The first approach, called
quantitative constraint logic programming, is conceptualized in a clear logical
framework, and presents a sound and complete system of quantitative inference
for definite clauses annotated with subjective weights. This approach combines
a rigorous formal semantics for quantitative inference based on subjective
weights with efficient weight-based pruning for constraint-based systems. The
second approach, called probabilistic constraint logic programming, introduces
a log-linear probability distribution on the proof trees of a constraint logic
program and an algorithm for statistical inference of the parameters and
properties of such probability models from incomplete, i.e., unparsed data. The
possibility of defining arbitrary properties of proof trees as properties of
the log-linear probability model and efficiently estimating appropriate
parameter values for them permits the probabilistic modeling of arbitrary
context-dependencies in constraint logic programs. The usefulness of these
ideas is evaluated empirically in a small-scale experiment on finding the
correct parses of a constraint-based grammar. In addition, we address the
problem of computational intractability of the calculation of expectations in
the inference task and present various techniques to approximately solve this
task. Moreover, we present an approximate heuristic technique for searching for
the most probable analysis in probabilistic constraint logic programs.

</DOC>
<DOC>
<DOCNO> 68867 </DOCNO>
Yukawa Unification, b --> s gamma and Bino-Stau Coannihilation


  The minimal supersymmetric standard model with universal boundary conditions
and "asymptotic" Yukawa unification is considered. The full one-loop effective
potential for radiative electroweak symmetry breaking as well as the one-loop
corrections to the charged Higgs boson, b-quark and tau lepton masses are
included. The CP-even Higgs boson masses are corrected to two-loops. The relic
abundance of the lightest supersymmetric particle (bino) is calculated by
including its coannihilations with the next-to-lightest supersymmetric particle
(lightest stau) consistently with Yukawa unification. The branching ratio of b
--> s gamma is evaluated by incorporating all the applicable next-to-leading
order QCD corrections. The bino-stau coannihilations reduce the bino relic
abundance below the upper bound from cold dark matter considerations in a
sizable fraction of the parameter space allowed by b --> s gamma for mu>0.
Thus, the mu>0 case, which also predicts an acceptable b-quark mass, is
perfectly compatible with data.

</DOC>
<DOC>
<DOCNO> 12172 </DOCNO>
Binding of Similarly Charged Plates: A Global Analysis


  Similarly and highly charged plates in the presence of multivalent counter
ions attract each other, leading to electrostatically bound states. Using
Monte-Carlo simulations we obtain the inter-plate pressure in the global
parameter space. The equilibrium plate separation, where the pressure changes
from attractive to repulsive, exhibits a novel unbinding transition. A
systematic and asymptotically exact strong-coupling field-theory yields the
bound state from a competition between counter-ion entropy and electrostatic
attraction, in agreement with simple scaling arguments.

</DOC>
<DOC>
<DOCNO> 122589 </DOCNO>
Fitting planes to early-type galaxies: MIST for the determination of the


  The present study deals with the problem of deriving the coefficients of the
fundamental plane (FP) of early-type galaxies.
  We introduce statistical models of the FP and relative fitting methods: the
MIST (Measurement errors and Intrinsic Scatter Three dimensional) fits. The
MIST fits account for the measurement errors on the variables and their
correlations as well as for the intrinsic scatter. We show that the lack of a
model of the intrinsic scatter of the FP is the origin of the systematic
differences between the various fitting methods.
  We also address the problem of estimating the uncertainties of the FP
coefficients and determine a simple relation between the sample size and the
expected accuracy of the coefficients.
  The present study leads to define a `minimum sample size' for a correct
estimate of the uncertainties. For N < 30, both theoretical formulae and
re-sampling techniques, like the bootstrap, do not give reliable estimates.
  The question of the 'universality' of the FP is addressed by applying the
MIST fits to ten samples of cluster galaxies. The FP slopes are actually
consistent between the different samples, but, due to the large uncertainties,
they could also hide significant systematic differences.
  The feasibility of the measurement of the possible variations of the FP
slopes as a function of redshift is also proved.

</DOC>
<DOC>
<DOCNO> 69328 </DOCNO>
Off-shell structure of the anomalous Z and gamma self-couplings


  We establish the general off-shell structure of the three neutral gauge boson
self-couplings V1*V2*V3*, with applications to the Z*Z*Z*, Z*Z*gamma*,
gamma*gamma*Z* cases. New coupling forms appear which do not exist when two
gauge bosons are on-shell. We give the contribution arising from a fermionic
triangle loop. It covers both the standard model (SM) and possible new physics
(NP) contributions like those arising in the MSSM. For what concerns NP
contributions with a high scale, we discuss the validity of an effective
Lagrangian involving a limited set of parameters. Finally we write the general
expression of the V1*V2*V3*-vertex contribution to the e+e- to (f(bar)
f)+(f'(bar) f') amplitude.

</DOC>
<DOC>
<DOCNO> 11320 </DOCNO>
Spin-1 Antiferromagnetic Heisenberg Chains in an External Staggered


  We present in this paper a nonlinear sigma-model analysis of a spin-1
antiferromagnetic Heisenberg chain in an external commensurate staggered
magnetic field. After rediscussing briefly and extending previous results for
the staggered magnetization curve, the core of the paper is a novel
calculation, at the tree level, of the Green functions of the model. We obtain
precise results for the elementary excitation spectrum and in particular for
the spin gaps in the transverse and longitudinal channels. It is shown that,
while the spectral weight in the transverse channel is exhausted by a single
magnon pole, in the longitudinal one, besides a magnon pole a two-magnon
continuum appears as well whose weight is a stedily increasing function of the
applied field, while the weight of the magnon decreases correspondingly. The
balance between the two is governed by a sum rule that is derived and
discussed. A detailed comparison with the present experimental and numerical
(DMRG) status of the art as well as with previous analytical approaches is also
made.

</DOC>
<DOC>
<DOCNO> 9340 </DOCNO>
Modified spin-wave description of the nuclear spin relaxation in


  We make a modified spin-wave description of the nuclear spin relaxation in
Heisenberg alternating-spin chains with antiferromagnetic exchange coupling. In
contrast with the conventional one-dimensional antiferromagnetic spin-wave
theory, which is plagued with the divergence of the sublattice magnetization
even in the ground state, the present spin-wave description is highly
successful over a wide temperature range. The temperature dependence of the
relaxation rate $T_1^{-1}$ significantly varies with the crystalline structure,
exhibiting both ferromagnetic and antiferromagnetic aspects. $T_1^{-1}$ further
shows a unique dependence on the applied field, which turns out an indirect
observation of the quadratic dispersion relations.

</DOC>
<DOC>
<DOCNO> 100374 </DOCNO>
On the action of the dual group on the cohomology of perverse sheaves on


  It was proved by Ginzburg and Mirkovic-Vilonen that the $G(O)$-equivariant
perverse sheaves on the affine grassmannian of a connected reductive group $G$
form a tensor category equivalent to the tensor category of finite dimensional
representations of the dual group $G^\vee$. The proof use the Tannakian
formalism. The purpose of this paper is to construct explicitely the action of
$G^\vee$ on the global cohomology of a perverse sheaf.

</DOC>
<DOC>
<DOCNO> 68909 </DOCNO>
Heavy Quark Pair Production in Polarized Photon--Photon Collisions


  We present the next-to-leading-order cross sections of the heavy
quark-antiquark pair production in polarized photon-photon collision for the
general case of photon polarizations. The numerical results for top-antitop
production cross sections together with production asymmetries are obtained for
linearly polarized photon-photon collisions, including one-loop QCD radiative
corrections.

</DOC>
<DOC>
<DOCNO> 116695 </DOCNO>
Phase Mixing of Nonlinear Plasma Oscillations in an Arbitrary Mass Ratio


  Nonlinear plasma oscillations in an arbitrary mass ratio cold plasma have
been studied using 1-D particle-in-cell simulation. In contrast to earlier work
for infinitely massive ion plasmas it has been found that the oscillations
phase mix away at any amplitude and that the rate at which phase mixing occurs,
depends on the mass ratio ($\Delta = m_{-}/m_{+}$) and the amplitude. A
perturbation theoretic calculation carried upto third order predicts that the
normalized phase mixing time $\omega_{p-} t_{mix}$ depends on the amplitude $A$
and the mass ratio $\Delta$ as $\sim [(A^{2}/24)(\Delta/\sqrt{1 +
\Delta})]^{-1/3}$. We have confirmed this scaling in our simulations and
conclude that stable non-linear oscillations which never phase mix, exist only
for the ideal case with $\Delta = 0.0$ and $A < 0.5$. These cold plasma results
may have direct relevance to recent experiments on superintense laser beam
plasma interactions with applications to particle acceleration, fast ignitor
concept etc.

</DOC>
<DOC>
<DOCNO> 119984 </DOCNO>
The Charge Transfer Efficiency and Calibration of WFPC2


  A new determination of WFPC2 photometric corrections is presented, using
HSTphot reduction of the WFPC2 Omega Centauri and NGC 2419 observations from
January 1994 through March 2000 and a comparison with ground-based photometry.
No evidence is seen for any position-independent photometric offsets (the
"long-short anomaly"); all systematic errors appear to be corrected with the
CTE and zero point solution. The CTE loss time dependence is determined to be
very significant in the Y direction, causing time-independent CTE solutions
(Stetson 1998; Saha, Lambert, & Prosser 2000) to be valid only for a small
range of times. On average, the present solution produces corrections similar
to Whitmore, Heyer, & Casertano (1999), although with an improved functional
form that produces less scatter in the residuals and determined with roughly a
year of additional data. In addition to the CTE loss characterization, zero
point corrections are also determined as functions of chip, gain, filter, and
temperature. Of interest, there are chip-to-chip differences of order 0.01-0.02
magnitudes relative to the Holtzman et al. (1995) calibrations, and the present
study provides empirical zero point determinations for the non-standard filters
such as the frequently-used F450W, F606W, and F702W.

</DOC>
<DOC>
<DOCNO> 102381 </DOCNO>
On the ordering of energy levels in homogeneous magnetic fields


  We study the energy levels of a single particle in a homogeneous magnetic
field and in an axially symmetric external potential. For potentials that are
superharmonic off the central axis, we find a general ``pseudoconcave''
ordering of the ground state energies of the Hamiltonian restricted to the
sectors with fixed angular momentum. The physical applications include atoms
and ions in strong magnetic fields. There the energies are monotone increasing
and concave in angular momentum. In the case of a periodic chain of atoms the
pseudoconcavity extends to the entire lowest band of Bloch functions.

</DOC>
<DOC>
<DOCNO> 13685 </DOCNO>
Band-structure trend in hole-doped cuprates and correlation with Tcmax


  By calculation and analysis of the bare conduction bands in a large number of
hole-doped high-temperature superconductors, we have identified the energy of
the so-called axial-orbital as the essential, material-dependent parameter. It
is uniquely related to the range of the intra-layer hopping. It controls the Cu
4s-character, influences the perpendicular hopping, and correlates with the
observed Tc at optimal doping. We explain its dependence on chemical
composition and structure, and present a generic tight-binding model.

</DOC>
<DOC>
<DOCNO> 11990 </DOCNO>
Improved perturbation theory in the vortex liquids state of type II


  We develop an optimized perturbation theory for the Ginzburg - Landau
description of thermal fluctuations effects in the vortex liquids. Unlike the
high temperature expansion which is asymptotic, the optimized expansion is
convergent. Radius of convergence on the lowest Landau level is $a_{T}=-3$ in
2D and $a_{T}=-5$ in 3D. It allows a systematic calculation of magnetization
and specific heat contributions due to thermal fluctuations of vortices in
strongly type II superconductors to a very high precision. The results are in
good agreement with existing Monte Carlo simulations and experiments.
Limitations of various nonperturbative and phenomenological approaches are
noted. In particular we show that there is no exact intersection point of the
magnetization curves both in 2D and 3D.

</DOC>
<DOC>
<DOCNO> 11283 </DOCNO>
Reentrant spin glass transition in


  Magnetic, electric and structural properties of
La$_{0.96-y}$Nd$_y$K$_{0.04}$MnO$_{3+\delta}$ with 0$\leq y \leq$0.4 have been
studied experimentally. A disordered magnetic state is formed as La is
substituted by Nd, reflecting the competition between ferromagnetic (FM) double
exchange and antiferromagnetic superexchange interactions. Key structural
parameters are identified and correlated with changes in magnetic and electric
properties. By application of a large magnetic field, spin disorder scattering
is removed, creating a new magnetoresistance peak at a temperature lower than
the first near-$T_c$ peak. Time dependent zero-field-cooled magnetisation
measurements have been performed for $y$=0.4 around this temperature. A
reentrant spin glass (RSG) transition is evidenced, with low field ageing
properties in both the RSG and FM phases, similar to those observed in
archetypal spin glass materials.

</DOC>
<DOC>
<DOCNO> 119612 </DOCNO>
Our Second Look at the Immature Universe: The Infrared View


  The long-awaited promise of studying high-redshift galaxies at long
wavelengths has been partially eclipsed by progress at optical wavelengths,
mostly because of the number of available pixels. It is nonetheless essential
to study optically selected high-redshift galaxies at wavelengths longward of
1\mic, for several reasons. One of the indications from such studies to date is
that interstellar dust (as an absorber of UV photons and re-emitter of IR
photons) plays an energetically significant role at high redshifts, just as it
does in present-day star-forming galaxies. This also provides a strong
motivation for new searches which detect high-redshift galaxies based on IR
observations. Some of these are already succeeding in clarifying our view of
galaxy evolution in the Immature Universe.

</DOC>
<DOC>
<DOCNO> 119670 </DOCNO>
Molecular gas in blue compact dwarf galaxies


  Blue compact dwarf galaxies (BCDGs) are currently undergoing strong bursts of
star formation. Nevertheless, only a few of them have been clearly detected in
CO, which is thought to trace the "fuel" of star formation: H_2. In this paper,
we present a deep search for CO J=1-->0 and J=2-->1 emission lines in a sample
of 8 BCDGs and two companions. Only 2 of them (Haro 2 and UM 465) are detected.
For the other galaxies we have obtained more stringent upper limits on the CO
luminosity than published values. We could not confirm the previously reported
``detection'' of CO for the galaxies UM 456 and UM 462. We analyze a possible
relation between metallicity, CO luminosity, and absolute blue magnitude of the
galaxies. We use previously determined relations between X = N(H_2)/I_CO and
the metallicity to derive molecular cloud masses or upper limits for them. With
these ``global'' X_CO values we find that for those galaxies which we detect in
CO, the molecular gas mass is similar to the HI mass, whereas for the
non-detections, the upper limits on the molecular gas masses are significantly
lower than the HI mass. Using an LVG (Large Velocity Gradient) model we show
that X_CO depends not only on metallicity, but also on other physical
parameters such as volume density and kinetic temperature, which rises the
question on the validity of ``global'' X_CO factors.

</DOC>
<DOC>
<DOCNO> 67872 </DOCNO>
K_{l4} decays


  An effective theory of large N_{C} QCD of mesons has been used to study six
K_{l4} decay modes. It has been found that the matrix elements of the
axial-vector current dominate the K_{l4} decays. PCAC is satisfied. A
relationship between three form factors of axial-vector current has been found.
Non-zero phase shifts are originated in \rho-->\pi\pi. The decay rates are
calculated in the chiral limit. In this study there is no adjustable parameter.

</DOC>
<DOC>
<DOCNO> 100081 </DOCNO>
Rank Equalities Related to Generalized Inverses of Matrices and Their


  This paper is divided into two parts. In the first part, we develop a general
method for expressing ranks of matrix expressions that involve Moore-Penrose
inverses, group inverses, Drazin inverses, as well as weighted Moore-Penrose
inverses of matrices. Through this method we establish a variety of valuable
rank equalities related to generalized inverses of matrices mentioned above.
Using them, we characterize many matrix equalities in the theory of generalized
inverses of matrices and their applications. In the second part, we consider
maximal and minimal possible ranks of matrix expressions that involve variant
matrices, the fundamental work is concerning extreme ranks of the two linear
matrix expressions $A - BXC$ and $A - B_1X_1C_1 - B_2X_2C_2$. As applications,
we present a wide range of their consequences and applications in matrix
theory.

</DOC>
<DOC>
<DOCNO> 101212 </DOCNO>
Polarized deformation quantization


  Let $A$ be a star product on a symplectic manifold $(M,\omega_0)$,
$\frac{1}{t}[\omega]$ its Fedosov class, where $\omega$ is a deformation of
$\omega_0$. We prove that for a complex polarization of $\omega$ there exists a
commutative subalgebra, $O$, in $A$ that is isomorphic to the algebra of
functions constant along the polarization.
  Let $F(A)$ consists of elements of $A$ whose commutator with $O$ belongs to
$O$. Then, $F(A)$ is a Lie algebra which is an $O$-extension of the Lie algebra
of derivations of $O$. We prove a formula which relates the class of this
extension, the Fedosov class, and the Chern class of $P$.

</DOC>
<DOC>
<DOCNO> 10164 </DOCNO>
Gaussian Tunneling Model of c-Axis Twist Josephson Junctions


  We calculate the critical current density $J^J_c$ for c-axis Josephson
tunneling between identical high temperature superconductors twisted an angle
$\phi_0$ about the c-axis. We model the tunneling matrix element squared as a
Gaussian in the change of wavevector q parallel to the junction,
$<|t({\bf q})|^2>\propto\exp(-{\bf q}^2a^2/2\pi^2\sigma^2)$. The
$J^J_c(\phi_0)/J^J_c(0)$ obtained for the s- and extended-s-wave order
parameters (OP's) are consistent with the Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$
data of Li {\it et al.}, but only for strongly incoherent tunneling,
$\sigma^2\ge0.25$. A $d_{x^2-y^2}$-wave OP is always inconsistent with the
data. In addition, we show that the apparent conventional sum rule violation
observed by Basov et al. might be understandable in terms of incoherent
c-axis tunneling, provided that the OP is not $d_{x^2-y^2}$-wave.

</DOC>
<DOC>
<DOCNO> 101428 </DOCNO>
Mechanical systems subjected to generalized nonholonomic constraints


  We study mechanical systems subject to constraint functions that can be
dependent at some points and independent at the rest. Such systems are modelled
by means of generalized codistributions. We discuss how the constraint force
can transmit an impulse to the motion at the points of dependence and derive an
explicit formula to obtain the ``post-impact'' momentum in terms of the
``pre-impact'' momentum.

</DOC>
<DOC>
<DOCNO> 174519 </DOCNO>
Chemical Equilibration and the Hadron-QGP Phase Transition


  We discuss recent experimental results on hadron multiplicities in
ultra-relativistic nuclear collisions. The data for central collisions are in
quantitative agreement with predictions of a thermal model assuming full
chemical equilibration. It is argued that this provides strong, albeit
indirect, evidence for the formation of a partonic phase in the collision prior
to hadron production.

</DOC>
<DOC>
<DOCNO> 11786 </DOCNO>
Coherent electron-phonon coupling and polaron-like transport in


  We present a technique to calculate the transport properties through
one-dimensional models of molecular wires. The calculations include inelastic
electron scattering due to electron-lattice interaction. The coupling between
the electron and the lattice is crucial to determine the transport properties
in one-dimensional systems subject to Peierls transition since it drives the
transition itself. The electron-phonon coupling is treated as a quantum
coherent process, in the sense that no random dephasing due to electron-phonon
interactions is introduced in the scattering wave functions. We show that
charge carrier injection, even in the tunneling regime, induces lattice
distortions localized around the tunneling electron. The transport in the
molecular wire is due to polaron-like propagation. We show typical examples of
the lattice distortions induced by charge injection into the wire. In the
tunneling regime, the electron transmission is strongly enhanced in comparison
with the case of elastic scattering through the undistorted molecular wire. We
also show that although lattice fluctuations modify the electron transmission
through the wire, the modifications are qualitatively different from those
obtained by the quantum electron-phonon inelastic scattering technique. Our
results should hold in principle for other one-dimensional atomic-scale wires
subject to Peierls transitions.

</DOC>
<DOC>
<DOCNO> 11505 </DOCNO>
Attractor Modulation and Proliferation in 1+$\infty$ Dimensional Neural


  We extend a recently introduced class of exactly solvable models for
recurrent neural networks with competition between 1D nearest neighbour and
infinite range information processing. We increase the potential for further
frustration and competition in these models, as well as their biological
relevance, by adding next-nearest neighbour couplings, and we allow for
modulation of the attractors so that we can interpolate continuously between
situations with different numbers of stored patterns. Our models are solved by
combining mean field and random field techniques. They exhibit increasingly
complex phase diagrams with novel phases, separated by multiple first- and
second order transitions (dynamical and thermodynamic ones), and, upon
modulating the attractor strengths, non-trivial scenarios of phase diagram
deformation. Our predictions are in excellent agreement with numerical
simulations.

</DOC>
<DOC>
<DOCNO> 13567 </DOCNO>
Absorption of a Randomly Accelerated Particle: Gambler's Ruin in a


  We consider a particle which is randomly accelerated by Gaussian white noise
on the line 0<x<1, with absorbing boundaries at x=0,1. Denoting the initial
position and velocity of the particle by x_0 and v_0 and solving a
Fokker-Planck type equation, we derive the exact probabilities q_0(x_0,v_0),
q_1(x_0,v_0) of absorption at x=0,1, respectively. The results are in excellent
agreement with computer simulations.

</DOC>
<DOC>
<DOCNO> 123127 </DOCNO>
Tunable-filter imaging of quasar fields at z~1. I. A cluster around MRC


  Using a combination of multicolour broad- and narrow-band imaging techniques
and follow-up spectroscopy, we have detected an overdensity of galaxies in the
field of quasar MRC B0450-221, whose properties are consistent with a cluster
at the quasar redshift z=0.9. An excess of red galaxies (V-I>2.2, I-K'>3.8) is
evident within 1' of the quasar, with the colours expected for galaxies at
z=0.9 that have evolved passively for 3 Gyr or more. A number of line-emitting
galaxies (nine candidates with equivalent widths EW>70A) are also detected in
the field using the TAURUS Tunable Filter (TTF). Three have been confirmed
spectroscopically to indeed lie at z=0.9. The TTF candidates with the strongest
[O II] line emission cluster in a group which lies 200-700 kpc away from the
quasar and the red galaxy excess, and therefore most likely on the outskirts of
the cluster. These observations are the first in a series probing quasar
environments at z~1 with TTF.

</DOC>
<DOC>
<DOCNO> 120906 </DOCNO>
Detection of Cosmic Shear with the William Herschel Telescope


  Gravitational lensing by large-scale structure induces weak coherent
alignments in the shapes of background galaxies. Here we present evidence for
the detection of this `cosmic shear' at the 3.4 sigma significance level with
the William Herschel Telescope. Analysis and removal of notable systematic
effects, such as shear induced by telescope optics and smearing by tracking and
seeing, are conducted in order to recover the physical weak shear signal.
Positive results for shear recovery on realistic simulated data are presented,
enhancing confidence in the measurement method. The detection of cosmic shear
is statistically characterised, and its cosmological significance is discussed.

</DOC>
<DOC>
<DOCNO> 150359 </DOCNO>
The RP^2 Valued Sigma and Baby Skyrme Models


  We investigate the sigma and baby Skyrme models with an RP^2 target space. We
compare these models to models with an S^2 target space. We investigate the
interactions between solitons and defects in the RP^2 sigma model.

</DOC>
<DOC>
<DOCNO> 119024 </DOCNO>
Theoretical Predictions for Surface Brightness Fluctuations and


  (Abridged) We present new theoretical predictions for surface brightness
fluctuations (SBFs) using models optimized for this purpose. Our predictions
agree well with SBF data for globular clusters and elliptical galaxies. We
provide refined theoretical calibrations and k-corrections needed to use SBFs
as standard candles. We suggest that SBF distance measurements can be improved
by using a filter around 1 micron and calibrating I-band SBFs with the
integrated V-K galaxy color. We also show that current SBF data provide useful
constraints on population synthesis models, and we suggest SBF-based tests for
future models. The data favor specific choices of evolutionary tracks and
spectra in the models among the several choices allowed by comparisons based on
only integrated light. In addition, the tightness of the empirical I-band SBF
calibration suggests that model uncertainties in post-main sequence lifetimes
are less than +/-50% and that the IMF in ellipticals is not much steeper than
that in the solar neighborhood. Finally, we analyze the potential of SBFs for
probing unresolved stellar populations. We find that optical/near-IR SBFs are
much more sensitive to metallicity than to age. Therefore, SBF magnitudes and
colors are a valuable tool to break the age/metallicity degeneracy. Our initial
results suggest that the most luminous stellar populations of bright cluster
galaxies have roughly solar metallicities and about a factor of three spread in
age.

</DOC>
<DOC>
<DOCNO> 101397 </DOCNO>
Homotopies and automorphisms of crossed modules of groupoids


  We give a detailed description of the structure of the actor 2-crossed module
related to the automorphisms of a crossed module of groupoids. This generalises
work of Brown and Gilbert for the case of crossed modules of groups, and part
of this is needed for work on 2-dimensional holonomy to be developed elsewhere
(see math.DG/0009082).

</DOC>
<DOC>
<DOCNO> 68156 </DOCNO>
Low energy onset of nuclear shadowing in photoabsorption


  The early onset of nuclear shadowing in photoabsorption at low photon
energies has recently been interpreted as a possible signature of a decrease of
the rho meson mass in nuclei. We show that one can understand this early onset
within simple Glauber theory if one takes the negative real part of the rho N
scattering amplitudes into account, corresponding to a higher effective mass of
the rho meson in nuclear medium.

</DOC>
<DOC>
<DOCNO> 102339 </DOCNO>
On the time evolution in totally constrained systems with weakly


  The Dirac method treatment for finite dimensional singular systems with
weakly vanishing Hamiltonian leads to obtain the equations of motion in terms
of parameter $\tau$. To obtain the correct equations of motion one should use
gauge fixing of the form $\tau - f(t)=0$. It is shown that the canonical method
leads to describe the evolution in both standard and constrained finite
dimensional systems with weakly vanishing Hamiltonian in terms of the physical
time $t$, without using any gauge fixing conditions. Besides the operator
quantization of the these systems is investigated using the canonical method
and it is shown that the evolution of the state $\Psi$ with the time $t$ is
described by the Schr/"odinger equation $i\frac{\partial \Psi}{\Partial t} =
{\hat H}\Psi$. The extension of this treatment to infinite dimensional systems
is given.

</DOC>
<DOC>
<DOCNO> 101199 </DOCNO>
Scattering rules in soliton cellular automata associated with crystal


  Solvable vertex models in a ferromagnetic regime give rise to soliton
cellular automata at q=0. By means of the crystal base theory, we study a class
of such automata associated with the quantum affine algebra U_q(g_n) for non
exceptional series g_n = A^{(2)}_{2n-1}, A^{(2)}_{2n}, B^{(1)}_n, C^{(1)}_n,
D^{(1)}_n and D^{(2)}_{n+1}. They possess a commuting family of time evolutions
and solitons labeled by crystals of the smaller algebra U_q(g_{n-1}).
Two-soliton scattering rule is identified with the combinatorial R of
U_q(g_{n-1})-crystals, and the multi-soliton scattering is shown to factorize
into the two-body ones.

</DOC>
<DOC>
<DOCNO> 68637 </DOCNO>
Can the mirror world explain the ortho-positronium lifetime puzzle?


  We suggest that the discrepant lifetime measurements of ortho-positronium can
be explained by ortho-positronium oscillations into mirror ortho-positronium.
This explanation can be tested in future vacuum experiments.

</DOC>
<DOC>
<DOCNO> 13950 </DOCNO>
Trapping Dynamics with Gated Traps: Stochastic Resonance-Like Phenomenon


  We present a simple one-dimensional trapping model prompted by the problem of
ion current across biological membranes. The trap is modeled mimicking the
ionic channel membrane behaviour. Such voltage-sensitive channels are open or
closed depending on the value taken by a potential. Here we have assumed that
the external potential has two contributions: a determinist periodic and a
stochastic one. Our model shows a resonant-like maximum when we plot the
amplitude of the oscillations in the absorption current vs. noise intensity.
The model was solved both numerically and using an analytic approximation and
was found to be in good accord with numerical simulations.

</DOC>
<DOC>
<DOCNO> 123279 </DOCNO>
AB Dor in '94: I. HST/GHRS Observations of the Quiescent Chromosphere of


  We analyze HST/GHRS spectra of AB Doradus, the prototypical ultra-rapidly
rotating K dwarf. We observed chromospheric (Mg II) and transition region (C
II, Si IV, C IV, and N V) lines periodically throughout the stellar rotation
period, and provide a low dispersion stellar atlas of 78 emission lines. The
quiescent line profiles of the chromospheric and transition region lines show
narrow cores superposed on very broad wings. The broad wings of the Mg II k & h
lines and of the transition region lines can be explained by emission from gas
co-rotating with the star and extending out to near the Keplerian co-rotation
radius (2.8 stellar radii). While this is not a unique solution, it is
consistent with previous studies of H-alpha emission that are naturally
explained by large co-rotating prominences. We find no evidence for rotational
modulation of the emission line fluxes. The density diagnostics suggest that
the transition region is formed at constant pressure, with an electron density
2-3 E12 /cm^3 at a temperature of 30,000 K. The electron pressure is about 100
times larger than that for the quiet Sun. The emission measure distribution
shows a minimum between log(T) = 5 and 5.5. The Mg II line exhibits three
interstellar absorption components along the 15 pc line of sight. We identify
the lowest velocity component with the G cloud, but the other components are
not identified with any interstellar clouds previously detected from other
lines of sight.

</DOC>
<DOC>
<DOCNO> 101927 </DOCNO>
Some infinite series related to Feynman diagrams


  Results are presented for some infinite series appearing in Feynman diagram
calculations, many of which are similar to the Euler series. These include both
one-, two- and three-dimensional series. The sums of these series can be
evaluated with the help of various integral representations for hypergeometric
functions, and expressed in terms of $\zeta(2)$, $\zeta(3)$, the Catalan
constant $G$ and ${\rm Cl}_2(\pi/3)$ where ${\rm Cl}_2(\theta)$ is Clausen's
function.

</DOC>
<DOC>
<DOCNO> 9994 </DOCNO>
Hellmann-Feynman theorem and fluctuation-correlation analysis of the


  Exploiting the results of the exact solution for the ground state of the
one-dimensional spinless quantum gas of Fermions and impenetrable Bosons with
the mu/x_{ij}^2 particle-particle interaction, the Hellmann-Feynman theorem
yields mutually compensating divergences of both the kinetic and the
interaction energy in the limiting case mu to -1/4. These divergences result
from the peculiar behavior of both the momentum distribution (for large
momenta) and the pair density (for small inter-particle separation). The
available analytical pair densities for mu=-1/4, 0, and 2 allow to analyze
particle-number fluctuations. They are suppressed by repulsive interaction
(mu>0), enhanced by attraction (mu<0), and may therefore measure the kind and
strength of correlation. Other recently proposed purely quantum-kinematical
measures of the correlation strength arise from the small-separation behavior
of the pair density or - for Fermions - from the non-idempotency of the
momentum distribution and its large-momenta behavior. They are compared with
each other and with reference-free, short-range correlation-measuring ratios of
the kinetic and potential energies.

</DOC>
<DOC>
<DOCNO> 11541 </DOCNO>
Long-term Relaxation of a Composite System in Partial Contact with a


  We study relaxational behavior from a highly excited state for a composite
system in partial contact with a heat bath, motivated by an experimental report
of long-term energy storage in protein molecules. The system consists of two
coupled elements: The first element is in direct contact with a heat bath,
while the second element interacts only with the first element. Due to this
indirect contact with the heat bath, energy injected into the second element
dissipates very slowly, according to a power law, whereas that injected into
the first one exhibits exponential dissipation. The relaxation equation
describing this dissipation is obtained analytically for both the underdamped
and overdamped limits. Numerical confirmation is given for both cases.

</DOC>
<DOC>
<DOCNO> 151671 </DOCNO>
An Exact Black Hole Entropy Bound


  We show that a Rademacher expansion can be used to establish an exact bound
for the entropy of black holes within a conformal field theory framework. This
convergent expansion includes all subleading corrections to the
Bekenstein-Hawking term.

</DOC>
<DOC>
<DOCNO> 101101 </DOCNO>
On the application of one M.G.Krein's result to the spectral analysis of


  Discovered by M.G.Krein analogy between polinomials orthogonal on the unit
circle and generalized eigenfunctions of certain differential systems is used
to obtain some new results in the spectral analysis of Sturm-Liouville
operators. Some properties of Dirac-type differential systems are studied.

</DOC>
<DOC>
<DOCNO> 9748 </DOCNO>
Integrable generalised spin ladder models


  We present two new integrable spin ladder models which posses three general
free parameters besides the rung coupling J. Wang's systems based on the SU(4)
and SU(3/1) symmetries can be obtained as special cases. The models are exactly
solvable by means of the Bethe ansatz method.

</DOC>
<DOC>
<DOCNO> 99690 </DOCNO>
SL(2) and z-measures


  We give a representation-theoretic proof of the formula for correlation
functions of z-measures obtained by Borodin and Olshanski in math.RT/9904010.
This paper is historically preceding my paper math.RT/9907127.

</DOC>
<DOC>
<DOCNO> 99632 </DOCNO>
A Note on the Intermediate Region in Turbulent Boundary Layers


  We demonstrate that the processing of the experimental data for the average
velocity profiles obtained by J. M. \"Osterlund
(www.mesh.kth.se/$\sim$jens/zpg/) presented in [1] was incorrect. Properly
processed these data lead to the opposite conclusion: they confirm the
Reynolds-number-dependent scaling law and disprove the conclusion that the flow
in the intermediate (`overlap') region is Reynolds-number-independent.

</DOC>
<DOC>
<DOCNO> 71871 </DOCNO>
Determining the sign of $\Delta_{31}$ at long baseline neutrino


  Recently it is advocated that high intensity and low energy $(E_\nu \sim 2
GeV)$ neutrino beams should be built to probe the $(13)$ mixing angle $\phi$ to
a level of a few parts in $10^4$. Experiments using such beams will have better
signal to background ratio in searches for $\nu_\mu \to \nu_e$ oscillations. We
propose that such experiments can also determine the sign of $\Delta_{31}$ even
if the beam consists of {\it neutrinos} only. By measuring the $\nu_\mu \to
\nu_e$ transitions in two different energy ranges, the effects due to
propagation of neutrinos through earth's crust can be isolated and the sign of
$\Delta_{31}$ can be determined. If the sensitivity of an experiment to $\phi$
is $\epsilon$, then the same experiment is automatically sensitive to matter
effects and the sign of $\Delta_{31}$ for values of $\phi \geq 2 \epsilon$.

</DOC>
<DOC>
<DOCNO> 80698 </DOCNO>
String breaking on a lattice


  String breaking is a non-perturbative long-distance feature of QCD that is
involved in for example meson decays. A mixing analysis of lattice operators at
zero temperature gives the level splitting and mixing energy between the broken
and unbroken string states.

</DOC>
<DOC>
<DOCNO> 70555 </DOCNO>
On the gauge parameter dependence of QED


  The gauge parameter dependence of QED in the covariant gauge can be
determined explicitly by introducing a Stueckelberg field, which is a
non-interacting fictitious Goldstone boson field. Examples of QED with
electrons or charged scalars are discussed. Our results generalize the long
known results on the gauge parameter dependence of the wave function
renormalization constant and the electron propagator.

</DOC>
<DOC>
<DOCNO> 99278 </DOCNO>
Askey-Wilson polynomials: an affine Hecke algebraic approach


  We study Askey-Wilson type polynomials using representation theory of the
double affine Hecke algebra. In particular, we prove bi-orthogonality relations
for non-symmetric and anti-symmetric Askey-Wilson polynomials with respect to a
complex measure. We give duality properties of the non-symmetric Askey-Wilson
polynomials, and we show how the non-symmetric Askey-Wilson polynomials can be
created from Sahi's intertwiners. The diagonal terms associated to the
bi-orthogonality relations (which replace the notion of quadratic norm
evaluations for orthogonal polynomials) are expressed in terms of residues of
the complex weight function using intertwining properties of the non-symmetric
Askey-Wilson transform under the action of the double affine Hecke algebra. We
evaluate the constant term, which is essentially the well-known Askey-Wilson
integral, using shift operators. We furthermore show how these results reduce
to well-known properties of the symmetric Askey-Wilson polynomials, as were
originally derived by Askey and Wilson using basic hypergeometric series
theory.

</DOC>
<DOC>
<DOCNO> 69023 </DOCNO>
QED in a Strong External Magnetic Field: Beyond the Constant Mass


  We solve the Schwinger-Dyson equations for QED in 2+1 or 3+1 dimensions in
the presence of a strong homogeneous external magnetic field. The magnetic
field is assumed strong enough, so that the lowest Landau level approximation
holds, but the usual assumption of a momentum-independent self-energy is not
made. In 2+1 dimensions, the scaling with logarithm changes to a square root
dependence on the magnetic field, but the most spectacular result takes place
in 3+1 dimensions, where the constant mass approximation turns out to be
unreliable and the (momentum-dependent) dynamical mass is larger by several
orders of magnitude compared to what has been found till now using the constant
mass approximation.

</DOC>
<DOC>
<DOCNO> 9089 </DOCNO>
Superconductors in realistic geometries: Geometric edge barrier versus


  The magnetic response of type-II superconductors can be irreversible due to
two different reasons: vortex pinning and barriers for flux penetration. Even
without bulk pinning and in absence of a microscopic Bean-Lingston surface
barrier for vortex penetration, superconductors of nonellipsoidal shape can
exhibit a large geometric barrier for flux penetration.
   This edge barrier and the resulting irreversible magnetization loops and
flux-density profiles are computed from continuum electrodynamics for
superconductor strips and disks with constant thickness, both without and with
bulk pinning. Expressions for the field of first flux entry H_en and for the
reversibility field H_rev above which the pin-free magnetization becomes
reversible are given. Both fields are proportional to the lower critical field
H_c1 and else depend only on the specimen shape. These realistic results are
compared with the reversible magnetic behavior of ideal superconductor
ellipsoids.

</DOC>
<DOC>
<DOCNO> 99442 </DOCNO>
Twisting the fake monster superalgebra


  We calculate twisted denominator identities of the fake monster superalgebra
and use them to construct new examples of supersymmetric generalized Kac-Moody
superalgebras. Their denominator identities give new infinite product
identities.

</DOC>
<DOC>
<DOCNO> 118794 </DOCNO>
The violent past of Cygnus X-2


  Cygnus X-2 appears to be the descendant of an intermediate-mass X-ray binary
(IMXB). Using Mazzitelli's (1989) stellar code we compute detailed evolutionary
sequences for the system and find that its prehistory is sensitive to stellar
input parameters, in particular the amount of core overshooting during the
main-sequence phase. With standard assumptions for convective overshooting a
case B mass transfer starting with a 3.5 M_sun donor star is the most likely
evolutionary solution for Cygnus X-2. This makes the currently observed state
rather short-lived, of order 3 Myr, and requires a formation rate > 1e-7 - 1e-6
per yr of such systems in the Galaxy. Our calculations show that neutron star
IMXBs with initially more massive donors (> 4 M_sun) encounter a delayed
dynamical instability; they are unlikely to survive this rapid mass transfer
phase. We determine limits for the age and initial parameters of Cygnus X-2 and
calculate possible dynamical orbits of the system in a realistic Galactic
potential, given its observed radial velocity. We find trajectories which are
consistent with a progenitor binary on a circular orbit in the Galactic plane
inside the solar circle that received a kick velocity < 200 km/s at the birth
of the neutron star. The simulations suggests that about 7% of IMXBs receiving
an arbitrary kick velocity from a standard kick velocity spectrum would end up
in an orbit similar to Cygnus X-2, while about 10% of them reach yet larger
Galactocentric distances.

</DOC>
<DOC>
<DOCNO> 84935 </DOCNO>
Biquaternion Electrodynamics and Weyl-Cartan Geometry of Space-Time


  The generalized Cauchy-Riemann equations (GCRE) in biquaternion algebra
appear to be Lorentz-invariant. The Laplace equation is in this case replaced
by a nonlinear (complexified) eikonal equation. GCRE contain the 2-spinor and
the gauge structures, and their integrability conditions take the form of
free-source Maxwell and Yang-Mills equations. For the value of electric charge
from GCRE only the quantization rule follows, as well as the treatment of
Coulomb law as a stereographic map. The equivalent geometrodynamics in a
Weyl-Cartan affine space and the conjecture of a complex-quaternion structure
of space-time are discussed.

</DOC>
<DOC>
<DOCNO> 120259 </DOCNO>
HeII Recombination Lines From the First Luminous Objects


  The hardness of the ionizing continuum from the first sources of UV radiation
plays a crucial role in the reionization of the intergalactic medium (IGM).
While usual stellar populations have soft spectra, mini-quasars or metal-free
stars with high effective temperatures may emit hard photons, capable of doubly
ionizing helium and increasing the IGM temperature. Absorption within the
source and in the intervening IGM will render the ionizing continuum of
high-redshift sources inaccessible to direct observation. Here we show that
HeII recombination lines from the first luminous objects are potentially
detectable by the Next Generation Space Telescope. Together with measurements
of the hydrogen Balmer alpha emission line, this detection can be used to infer
the ratio of HeII to HI ionizing photons. A measurement of this ratio would
shed light on the nature and emission mechanism of the first luminous sources,
with important astrophysical consequences for the reheating and reionization of
the IGM.

</DOC>
<DOC>
<DOCNO> 7662 </DOCNO>
Statistical Physics of the Travelling Salesman Problem


  If one places N cities on a continuum in an unit area, extensive numerical
results and their analysis (scaling, etc.) suggest that the best normalized
optimal travel distance becomes 0.72 for the Euclidean metric and 0.92 for the
Manhattan metric. The analytic bounds, we discuss here, give 0.5 and 0.92 as
the lower and upper bounds for the Euclidean metric, and 0.64 and 1.17 for the
Manhattan metric. When the cities are randomly placed on a lattice with
concentration p, we find that the normalized optimal travel distance vary
monotonically with p. For p=1, the values in both Euclidean and Manhattan
metric are 1, and as p tends to zero, the values are 0.72 and 0.92 in the
Euclidean and Manhattan metrics respectively.The problem is trivial for p=1 but
it reduces to the continuum TSP as p tends to zero. We do not get any irregular
behaviour at any intermediate point, e.g., the percolation point. The crossover
from the triviality to the NP- hard problem seems to occur at p<1.

</DOC>
<DOC>
<DOCNO> 69833 </DOCNO>
Statistical treatment of detection cross-section uncertainties in the


  We propose a modification to the standard statistical treatment of the
detection cross-section uncertainties in the analysis of solar neutrino data.
We argue that the uncertainties of the energy-averaged cross sections of the
different neutrino fluxes in the same experiment should be treated as
correlated. We show that the resulting allowed regions for the neutrino
oscillation parameters are significantly larger than the ones obtained with
uncorrelated uncertainties.

</DOC>
<DOC>
<DOCNO> 120262 </DOCNO>
Stellar orbits in triaxial clusters around black holes in galactic


  We investigate the orbital structure of a model triaxial star cluster,
centered around a supermassive black hole (BH), appropriate to galactic nuclei.
Sridhar and Touma (1999) proved that the presence of the BH enforces some
regularity in the dynamics within the radius of influence of the BH. We employ
their averaging method to reduce the degrees of freedom from three to two.
Numerical orbit integrations, together with Poincar\'e surfaces of section
allow us to draw a global portrait of the orbital structure; in our
calculations we employ a model cluster potential that is triaxial and harmonic.
The averaged dynamics of the axisymmetric case is integrable, and we present a
detailed comparison of orbits in oblate and prolate axisymmetric potentials.
Both cases support resonant orbits with fixed values of eccentricity,
inclination, and periapse, whose lines of nodes rotates steadily. We then
systematically explore significantly triaxial potentials, possessing small
oblateness, or prolateness. Resonant orbits and their families are studied both
numerically, and through secular perturbation theory. Chaos appears to be
suppressed for all the cases we studied, and we obtain effective third
integrals. Some of the orbits appear to reinforce the shape of the potential;
we provide phase space, as well as real space portraits of these orbits. A
particularly promising resonant orbit exists in highly prolate, triaxial
potentials.

</DOC>
<DOC>
<DOCNO> 39986 </DOCNO>
Micrometer Gravitinos and the Cosmological Constant


  We compute the 4--dimensional cosmological constant in string
compactifications in which the Standard Model fields live on a
non-supersymmetric brane inside a supersymmetric bulk. The cosmological
constant receives contributions only from the vacuum energy of the bulk
supergravity fields, but not from the vacuum energy of the brane fields. The
latter is absorbed in a warp factor. Supersymmetry breaking on the brane at the
TeV scale implies supersymmetry breaking in the bulk at the micrometer scale.
This produces a tiny cosmological constant that agrees with experiment within a
few orders of magnitude. Our argument predicts superpartners of the graviton
with mass of order $10^{-3}$ eV. They should be observable in short-distance
tests of Einstein Gravity.

</DOC>
<DOC>
<DOCNO> 119218 </DOCNO>
Transient Gamma Ray Spectrometer Measurements of Gamma-Ray Lines from


  The Transient Gamma Ray Spectrometer (TGRS) on board the WIND spacecraft has
spent most of the interval 1995-1997 in a high-altitude orbit where gamma-ray
backgrounds are low. Its high-resolution Ge spectrometer is thus able to detect
weak lines which are slightly offset from stronger background features. One
such line is predicted from nucleosynthesis in classical novae, where
beta-decays on a time-scale of a few hours in an expanding envelope produce
positrons that annihilate to generate a line which is blueshifted by a few keV
away from the background annihilation line at 511 keV. The broad TGRS field of
view contained five known Galactic novae during 1995 January - 1997 June, and
we have searched the spectra taken around the times of these events for the
blueshifted nova annihilation line. Although no definite detections were made,
the method is shown to be sensitive enough to detect novae occurring on
ONeMg-rich white dwarfs out to about 2.5 kpc.

</DOC>
<DOC>
<DOCNO> 101853 </DOCNO>
Restricted 132-avoiding permutations


  We study generating functions for the number of permutations on n letters
avoiding 132 and an arbitrary permutation $\tau$ on k letters, or containing
$\tau$ exactly once. In several interesting cases the generating function
depends only on k and is expressed via Chebyshev polynomials of the second
kind.

</DOC>
<DOC>
<DOCNO> 70441 </DOCNO>
Bottom-up model for maximal $\nu_{\mu} - \nu_{\tau}$ mixing


  We construct a model which provides maximal mixing between a pseudo-Dirac
$\nu_{\mu}/\nu_{\tau}$ pair, based on a local $U(1)_{L_{\mu}-L_{\tau}}$
symmetry. Its strengths, weaknesses and phenomenological consequences are
examined. The mass gap necessitated by the pseudo-Dirac structure is most
naturally associated with the LSND anomaly. The solar neutrino problem then
requires a light mirror or sterile neutrino. By paying a fine-tuning price to
nullify the mass gap, one can also invoke $\nu_e \to \nu_{\mu,\tau}$ for the
solar problem. The model predicts a new intermediate range force mediated by
the light gauge boson of $U(1)_{L_{\mu}-L_{\tau}}$. Through the mixing of
$\mu$, $\tau$ and $e$, this force couples to electrons and thus may be searched
for in precision ``gravity'' experiments.

</DOC>
<DOC>
<DOCNO> 84424 </DOCNO>
Toward a Traversable Wormhole


  In this talk I discuss pertinence of the wormholes to the problem of
circumventing the light speed barrier and present a specific class of
wormholes. The wormholes of this class are static and have arbitrarily wide
throats, which makes them traversable. The matter necessary for these
spacetimes to be solutions of the Einstein equations is shown to consist of two
components, one of which satisfies the Weak energy condition and the other is
produced by vacuum fluctuations of neutrino, electromagnetic (in dimensional
regularization), and/or massless scalar (conformally coupled) fields.

</DOC>
<DOC>
<DOCNO> 102267 </DOCNO>
Maximal abelian subalgebras of O_n


  We consider maximal abelian subalgebras of O_n which are invariant to the
standard circle action.

</DOC>
<DOC>
<DOCNO> 118864 </DOCNO>
Hybrid Thermal-Nonthermal Synchrotron Emission from Hot Accretion Flows


  We investigate the effect of a hybrid electron population, consisting of both
thermal and non-thermal particles, on the synchrotron spectrum, image size, and
image shape of a hot accretion flow onto a supermassive black hole. We find two
universal features in the emitted synchrotron spectrum: (i) a prominent
shoulder at low (< 10^11 Hz) frequencies that is weakly dependent on the shape
of the electron energy distribution, and (ii) an extended tail of emission at
high (> 10^13 Hz) frequencies whose spectral slope depends on the slope of the
power-law energy distribution of the electrons. In the low-frequency shoulder,
the luminosity can be up to two orders of magnitude greater than with a purely
thermal plasma even if only a small fraction (< 1%) of the steady-state
electron energy is in the non-thermal electrons. We apply the hybrid model to
the Galactic center source, Sgr A*. The observed radio and IR spectra imply
that at most 1% of the steady-state electron energy is present in a power-law
tail in this source. This corresponds to no more than 10% of the electron
energy injected into the non-thermal electrons and hence 90% into the thermal
electrons. We show that such a hybrid distribution can be sustained in the flow
because thermalization via Coulomb collisions and synchrotron self-absorption
are both inefficient. The presence of non-thermal electrons enlarges the size
of the radio image at low frequencies and alters the frequency dependence of
the brightness temperature. A purely thermal electron distributions produces a
sharp-edged image while a hybrid distribution causes strong limb brightening.
These effects can be seen up to frequencies ~10^11 Hz and are accessible to
radio interferometers.

</DOC>
<DOC>
<DOCNO> 39837 </DOCNO>
The $\phi\to\eta\pi^0\gamma$ decay


  Rare radiative decay $\phi\to\eta\pi^0\gamma$ was studied with SND detector
at {VEPP-2M} electron-positron collider and its branching ratio was measured:
$B(\phi\to\eta\pi^0\gamma)=(0.88\pm0.14\pm0.09)\cdot 10^{-4}$. Significant
contribution of the $a_0(980)\gamma$ intermediate state was observed in the
decay. The result is based on total integrated luminosity corresponding to
$2\cdot10^7$ produced $\phi$ mesons.

</DOC>
<DOC>
<DOCNO> 152163 </DOCNO>
Monopoles, Instantons and Confinement


  We review the physics of topological objects in QCD. Topics include:
solitons, vortices, magnetic monopoles, instantons, (effective theories of)
confinement.

</DOC>
<DOC>
<DOCNO> 101890 </DOCNO>
A theory of quaternionic algebra, with applications to hypercomplex


  In this paper we introduce a new algebraic device, which enables us to treat
the quaternions as though they were a commutative field. This is of interest
both for its own sake, and because it can be applied to develop an "algebraic
geometry" of noncompact hypercomplex manifolds.
  The basic building blocks of the theory are AH modules, which should be
thought of "vector spaces" over the quaternions. An AH-module is a left module
over the quaternions H, together with a real vector subspace. There are natural
concepts of linear map and tensor product of AH-modules, which have many of the
properties of linear maps and tensor products of vector spaces. However, the
definition of tensor product of AH-modules is strange and has some unexpected
properties.
  Let M be a hypercomplex manifold. Then there is a natural class of H-valued
"q-holomorphic functions" on M, satisfying a quaternionic analogue of the
Cauchy-Riemann equations, which are analogues of holomorphic functions on
complex manifolds. The vector space of q-holomorphic functions A on M is an
AH-module.
  Now some pairs of q-holomorphic functions can be multiplied together to get
another q-holomorphic function, but other pairs cannot. So A has a kind of
partial algebra structure. It turns out that this structure can be very neatly
described using the quaternionic tensor product and AH-morphisms, and that A
has the structure of an "H-algebra", a quaternionic analogue of commutative
algebra.

</DOC>
<DOC>
<DOCNO> 101228 </DOCNO>
An endpoint estimate for the Kunze-Stein phenomenon and related maximal


  One of the purposes of this paper is to prove that if G is a noncompact
connected semisimple Lie group of real rank one with finite center, then
L^{2,1}(G)\ast L^{2,1}({G})\subseteq L^{2,\infty}({G}). Let {K} be a maximal
compact subgroup of {G} and X=G/K a symmetric space of real rank one. We will
also prove that the noncentered maximal operator {\cal M}_2f(z) = \sup_{z\in
B} \frac{1}{|B|} \int_{B}|f(z')|\,dz' is bounded from L^{2,1}(X) to
L^{2,\infty}(X) and from L^p(X) to L^p(X) in the sharp range of exponents
p\in(2,\infty]. The supremum in the definition of {\cal M}_2f(z) is taken over
all balls containing the point z.

</DOC>
<DOC>
<DOCNO> 122384 </DOCNO>
On the role of extinction in failed gamma-ray burst optical/IR


  While all but one Gamma-Ray Bursts observed in the X-ray band showed an X-ray
afterglow, about 60 per cent of them have not been detected in the optical
band. We demonstrate that in many cases this is not due to adverse observing
conditions, or delay in performing the observations. We also show that the
optically non-detected afterglows are not affected by particularly large
Galactic absorbing columns, since its distribution is similar for both the
detected and non-detected burst subclasses. We then investigate the hypothesis
that the failure of detecting the optical afterglow is due to absorption at the
source location. We find that this is a marginally viable interpretation, but
only if the X-ray burst and afterglow emission and the possible optical/UV
flash do not destroy the dust responsible for absorption in the optical band.
If dust is efficiently destroyed, we are led to conclude that bursts with no
detected optical afterglow are intrinsically different. Prompt infrared
observations are the key to solve this issue.

</DOC>
<DOC>
<DOCNO> 70742 </DOCNO>
Strong CP problem and mirror world: the Weinberg Wilczek axion revisited


  A new possibility for solving the strong CP-problem is suggested,which
assumes that apart of the ordinary world of observable particles described by
standard model, there exits a mirror sector of particles and two sectors share
the same Peccei-Quinn symmetry realized {\it a l\`a} Weinberg-Wilczek model.
The mirror gauge group is completely analogous to that of the standard model
for ordinary particles but having somewhat larger electroweak scale,which in
turn implies the infrared scale $\Lambda'$ of the mirror strong interactions
has to be larger than the ordinary QCD scale $\Lambda$. In this way, the axion
mass and interaction constants are actually determined by mirror sector scales
$v'$ and $\Lambda'$, while the $\theta$ terms are simultaneously cancelled in
both sectors due to mirror symmetry. The experimental and astrophysical limits
on such an axion is discussed. An interesting parameter window is found where
$f_a \sim {\rm few}\times 10^4$ GeV whereas the axion mass is $\sim 1$ MeV.

</DOC>
<DOC>
<DOCNO> 122725 </DOCNO>
Luminous compact galaxies at intermediate redshifts: progenitors of


  VLT spectra of 14 luminous compact galaxies (LCGs) reveal strong metallic
absorption line sytems as well as narrow and intense emission lines. Their gas
extinction is found to be large (Av ~ 1.5 mag) leading to an upward revision of
their star formation rate (SFR) to an average value of ~ 40 Mo/yr. Large
extinction values are also supported by the large rate of detection in one
field observed by ISO. Gas metal abundances in LCGs have about half the solar
value. We argue that LCGs are the progenitors of present-day spiral bulges.
LCGs have masses and light concentrations similar to those of present-day
bulges. As in present-day galactic bulges, LCG stars show a wide range of
abundances. Thus, observing LCGs allows us to directly witness an important
stage in the formation of a massive galaxy, the building of the bulge prior to
that of the disk. The gas needed to feed the observed star formation is likely
to be falling in from the outskirts of the galaxy, being tidally pulled out
from interacting companion galaxies. Some LCGs also show evidence for the
beginning of a disk formation. If the above scenario holds for most LCGs, we
estimate that at least 20% of present-day spiral galaxies have formed the bulk
of their stars at relatively recent epochs, during the last 8-9 Gyr, at
redshifts less than ~ 1. Since they are heavily extincted, we predict their IR
luminosities to be relatively large, around Lir = 10^11 Lsun, i.e. near or
slightly below the luminosities of the galaxies detected by ISO in the same
redshift range. Taking into account the integrated IR luminosity of the LCG
galaxy population can lead to a significant upward revision of the cosmic SFR
density in the redshift range from 0.5 to 1.

</DOC>
<DOC>
<DOCNO> 11902 </DOCNO>
Peltier effect induced longitudinal resistivity of ideal 2D


  We demonstrate that in strong quantum limit the thermoelectric Peltier effect
could define the longitudinal resistivity of dissipationless two-dimensional
electron(hole) gas. The current results in heating(cooling) at first(second)
Hall bar sample contact due to Peltier effect. At small current the contacts
temperatures are different, the temperature gradient is linear on current. The
voltage swing downstream the current is proportional to Peltier effect induced
thermopower. As a result, nonzero longitudinal resistivity is measured in
experiment. The above effect could exist in 3D case.

</DOC>
<DOC>
<DOCNO> 152284 </DOCNO>
D-brane probes, RR tadpole cancellation and K-theory charge


  We study RR charge cancellation consistency conditions in string
compactifications with open string sectors, by introducing D-brane probes in
the configuration. We show that uncancelled charges manifest as chiral gauge
anomalies in the world-volume of suitable probes. RR tadpole cancellation can
therefore be described as the consistency of the effective compactified theory
not just in the vacuum, but also in all topological sectors (presence of
D-brane probes). The result explains why tadpole cancellation is usually much
stronger than anomaly cancellation of the compactified theory (in the vacuum
sector). We use the probe criterion to construct consistent six-dimensional
orientifolds of curved K3 spaces, where usual CFT techniques to compute
tadpoles are not valid. As a last application, we consider compactifications
where standard RR charge cancels but full K-theory charge does not. We show the
inconsistency of such models manifests as a global gauge anomaly on the
world-volume of suitable probes.

</DOC>
<DOC>
<DOCNO> 12345 </DOCNO>
Paramagnetic Meissner effect in superconductors from self-consistent


  The paramagnetic Meissner effect (PME) is observed in small superconducting
samples, and a number of controversial explanations of this effect are
proposed, but there is as yet no clear understanding of its nature. In the
present paper PME is considered on the base of the Ginzburg-Landau theory (GL).
The one-dimensional solutions are obtained in a model case of a long
superconducting cylinder for different cylinder radii R, the GL-parameters
\kappa and vorticities m. Acording to GL-theory, PME is caused by the presence
of vortices inside the sample. The superconducting current flows around the
vortex to screeen the vortex own field from the bulk of the sample. Another
current flows at the boundary to screen the external field H from entering the
sample. These screening currents flow in opposite directions and contribute
with opposite signs to the total magnetic moment (or magnetization) of the
sample. Depending on H, the total magnetization M may be either negative
(diamagnetism), or positive (paramagnetism). A very complicated saw-like
dependence M(H) (and other characteristics), which are obtained on the base of
self-consistent solutions of the GL-equations, are discussed.

</DOC>
<DOC>
<DOCNO> 80619 </DOCNO>
Polarized structure functions from the lattice


  We give a brief sketch of lattice structure function calculations and review
previous results for the axial coupling $g_A$. We outline a new technique for
treating fermions on the lattice that preserves chiral symmetry, domain wall
fermions. Finally, we give preliminary results for the nucleon spectrum using
this new technique. Remarkably, a large mass splitting between the $N$ and
$N^*$, roughly consistent with experiment, is produced in the calculation.
These results are encouraging for proposed calculations of nucleon structure
functions.

</DOC>
<DOC>
<DOCNO> 39685 </DOCNO>
On Upper Limits for Gravitational Radiation


  A procedure with a Bayesan approach for calculating upper limits to
gravitational wave bursts from coincidence experiments with multiple detectors
is described.

</DOC>
<DOC>
<DOCNO> 8947 </DOCNO>
Glass transition of a particle in a random potential, front selection in


  We study via RG, numerics, exact bounds and qualitative arguments the
equilibrium Gibbs measure of a particle in a $d$-dimensional gaussian random
potential with {\it translationally invariant logarithmic} spatial
correlations. We show that for any $d \ge 1$ it exhibits a transition at
$T=T_c>0$. The low temperature glass phase has a non trivial structure, being
dominated by {\it a few} distant states (with replica symmetry breaking
phenomenology). In finite dimension this transition exists only in this
``marginal glass'' case (energy fluctuation exponent $\theta=0$) and disappears
if correlations grow faster (single ground state dominance $\theta>0$) or
slower (high temperature phase). The associated extremal statistics problem for
correlated energy landscapes exhibits universal features which we describe
using a non linear (KPP) RG equation. These include the tails of the
distribution of the minimal energy (or free energy) and the finite size
corrections which are universal. The glass transition is closely related to
Derrida's random energy models. In $d=2$ the glass transition of the particle
exhibits interesting similarities with the weak to strong coupling transition
in Liouville ($c=1$ barrier) and with a transition that we conjecture for the
sinh-Gordon model. Glassy freezing of the particle is associated with the
generation under RG of new local operators and of non-smooth configurations in
Liouville. Applications to Dirac fermions in random magnetic fields at
criticality reveals a peculiar ``quasi-localized'' regime (the glass phase for
the particle) where eigenfunctions are concentrated over {\it a finite number}
of distant regions, and allows to recover the multifractal spectrum.

</DOC>
<DOC>
<DOCNO> 121873 </DOCNO>
Are CSO host-galaxies undergoing merging?


  The galaxy-type CSO (compact symmetric objects) rate from an intermediate
large sample PR+CJ1 is found to be consistent with the Sb-Sb merger rate of
4.6% in redshift z<1. The CSO detection rate seems going down when the sample
size is increasing, which could not reach the high merger rate in z>1, yet no
deep VLBI sample in z>1 is available now.

</DOC>
<DOC>
<DOCNO> 178792 </DOCNO>
Symmetry Violation in Heavy Nuclei


  The advantage of searching for violation of Time Reversal Invariance in
neutron induced reactions using relative measurements of Time and Parity
violating effects is discussed. This approach gives the enhancement of
$T$-violating effects by many orders of magnitude and, at the same time,
decrees theoretical uncertainties and experimental errors.

</DOC>
<DOC>
<DOCNO> 118141 </DOCNO>
The Warp of the Galaxy and the Orientation of the LMC Orbit


  After studying the orientation of a warp generated by a companion satellite,
we show that the Galactic Warp would be oriented in a different way if the
Magellanic Clouds were its cause. We have treated the problem analytically, and
complemented it with numerical N-Body simulations.

</DOC>
<DOC>
<DOCNO> 84435 </DOCNO>
New quantum aspects of a vacuum-dominated universe


  In a new model that we proposed, nonperturbative vacuum contributions to the
effective action of a free quantized massive scalar field lead to a
cosmological solution in which the scalar curvature becomes constant after a
time $t_j$ (when the redshift $z \sim 1$) that depends on the mass of the
scalar field and its curvature coupling. This spatially-flat solution implies
an accelerating universe at the present time and gives a good one-parameter fit
to high-redshift Type Ia supernovae (SNe-Ia) data, and the present age and
energy density of the universe. Here we show that the imaginary part of the
nonperturbative curvature term that causes the cosmological acceleration,
implies a particle production rate that agrees with predictions of other
methods and extends them to non-zero mass fields. The particle production rate
is very small after the transition and is not expected to alter the nature of
the cosmological solution. We also show that the equation of state of our model
undergoes a transition at $t_j$ from an equation of state dominated by
non-relativistic pressureless matter (without a cosmological constant) to an
effective equation of state of mixed radiation and cosmological constant, and
we derive the equation of state of the vacuum. Finally, we explain why
nonperturbative vacuum effects of this ultralow-mass particle do not
significantly change standard early universe cosmology.

</DOC>
<DOC>
<DOCNO> 120950 </DOCNO>
Observational signatures of X-ray irradiated accretion disks


  Reflection of X-rays from cool material around a black hole is one of the few
observational diagnostics of the accretion flow geometry. Models of this
reflected spectrum generally assume that the accretion disk can be
characterized by material in a single ionization state. However, several
authors have recently stressed the importance of the classic ionization
instability for X-ray irradiated gas in hydrostatic balance. This instability
leads to a discontinuous transition in the vertical structure of the disk,
resulting in a hot ionized skin above much cooler material. If the Compton
temperature of the skin is high then even iron is completely ionized, and the
skin does not produce any spectral features. These new models, where the
ionization structure of the disk is calculated self-consistently, require an
excessive amount of computing power and so are difficult to use in directly
fitting observed X-ray spectra. Instead, we invert the problem by simulating
X-ray spectra produced by the new reflection models, and then fit these with
the old, single zone reflection models, to assess the extent to which the
derived accretion geometry depends on the reflection model used. We find that
the single zone ionization models can severely underestimate the covering
fraction of the ``cold'' material as seen from the X-ray source if the optical
depth in the ionized skin is of order unity, and that this can produce an
apparent correlation between the covering fraction and the X-ray spectral index
similar in nature to that reported by Zdziarski, Lubinski and Smith (1999).

</DOC>
<DOC>
<DOCNO> 9956 </DOCNO>
Parity Effects in Stacked Nanoscopic Quantum Rings


  The ground state and the dielectric response of stacked quantum rings are
investigated in the presence of an applied magnetic field along the ring axis.
For odd number $N$ of rings and an electric field perpendicular to the axis, a
linear Stark effect occurs at distinct values of the magnetic field. At those
fields energy levels cross in the absence of electric field. For even values of
$N$ a quadratic Stark effect is expected in all cases, but the induced electric
polarization is discontinuous at those special magnetic fields. Experimental
consequences for related nanostructures are discussed.

</DOC>
<DOC>
<DOCNO> 120855 </DOCNO>
Are X-ray properties of loose groups different from those of compact


  We compare the X-ray properties of loose and compact galaxy groups, using a
combined sample of 42 groups. We find that we are unable to separate loose and
compact groups on the luminosity-temperature relation, the luminosity-velocity
dispersion relation or the velocity dispersion-temperature relation using
equally weighted errors. This suggests that the distinction between compact and
loose groups is not a fundamental one, and we argue that a more useful
distinction is that between X-ray bright and X-ray faint systems. Given their
similarity in X-ray properties, we combine the loose and compact subsamples to
derive relations based on the full sample. This provides the highest
statistical quality results to date on the way in which the correlations in
X-ray properties of low mass systems depart from those seen in rich clusters.

</DOC>
<DOC>
<DOCNO> 170404 </DOCNO>
Bounds on quantum ordered searching


  We prove that any exact quantum algorithm searching an ordered list of N
elements requires more than \frac{1}{\pi}(\ln(N)-1) queries to the list. This
improves upon the previously best known lower bound of {1/12}\log_2(N) - O(1).
  Our proof is based on a weighted all-pairs inner product argument, and it
generalizes to bounded-error quantum algorithms.
  The currently best known upper bound for exact searching is roughly 0.526
\log_2(N).
  We give an exact quantum algorithm that uses \log_3(N) + O(1) queries, which
is roughly 0.631 \log_2(N). The main principles in our algorithm are an quantum
parallel use of the classical binary search algorithm and a method that allows
basis states in superpositions to communicate.

</DOC>
<DOC>
<DOCNO> 170231 </DOCNO>
Bell State Preparation using Pulsed Non-Degenerate Two-Photon


  We report a novel Bell state preparation experiment. High-purity Bell states
are prepared by using femtosecond pulse pumped \emph{nondegenerate} collinear
spontaneous parametric down-conversion. The use of femtosecond pump pulse {\em
does not} result in reduction of quantum interference visibility in our scheme
in which post-selection of amplitudes and other traditional mechanisms, such
as, using thin nonlinear crystals or narrow-band spectral filters are not used.
Another distinct feature of this scheme is that the pump, the signal, and the
idler wavelengths are all distinguishable, which is very useful for quantum
communications.

</DOC>
<DOC>
<DOCNO> 122528 </DOCNO>
The disc-jet connection in GRS 1915+105


  We have compared simultaneous Ryle Telescope (RT) radio and Rossi X-Ray
Timing Explorer (RXTE) X-ray observations of the galactic microquasar GRS
1915+105. We find that radio emission, and therefore also the radio jet,
requires the presence of long (~100s), hard dips in the X-ray light curve which
seem to have a one-to-one relation with the radio events: each hard dip
produces a new radio "flare". We discuss the characteristic features of the
connection between the hard X-ray states and the radio emission.

</DOC>
<DOC>
<DOCNO> 9069 </DOCNO>
The N boson time dependent problem: an exact approach with stochastic


  We present a numerically tractable method to solve exactly the evolution of a
N boson system with binary interactions. The density operator of the system rho
is obtained as the stochastic average of particular operators |Psi_1><Psi_2| of
the system. The states |Psi_{1,2}> are either Fock states |N:phi_{1,2}> or
coherent states |coh:phi_{1,2}> with each particle in the state phi_{1,2}. We
determine the conditions on the evolution of phi_{1,2} -which involves a
stochastic element- under which we recover the exact evolution of rho. We
discuss various possible implementations of these conditions. The well known
positive P-representation arises as a particular case of the coherent state
ansatz. We treat numerically two examples: a two-mode system and a
one-dimensional harmonically confined gas. These examples, together with an
analytical estimate of the noise, show that the Fock state ansatz is the most
promising one in terms of precision and stability of the numerical solution.

</DOC>
<DOC>
<DOCNO> 10389 </DOCNO>
Behavior of the thermopower in amorphous materials at the


  We study the thermal transport properties in three-dimensional disordered
systems close to the metal-insulator transition within linear response. Using a
suitable form for the energy-dependent conductivity $\sigma$, we show that the
value of the dynamical scaling exponent for noninteracting disordered systems
such as the Anderson model of localization can be reproduced. Furthermore, the
values of the thermopower S have the right order of magnitude close to the
transition as compared to the experimental results. A sign change in the
thermoelectric power S - as is often observed in experiments - can also be
modeled within the linear response formulation using modified experimental
$\sigma$ data as input.

</DOC>
<DOC>
<DOCNO> 116908 </DOCNO>
Space Charge Effects in Bunch Shape Monitors


  The operation and parameters of Bunch Shape Monitors using coherent
transformation of time structure of an analyzed beam into a spatial one of low
energy secondary electrons emitted from a wire target is influenced by the
characteristics of a beam under study. The electromagnetic field of a bunch
disturbs the trajectories of secondary electrons, thus resulting in a
degradation of phase resolution and in errors of phase reading. Another effect
is the perturbation of the target potential due to the current in the wire
induced by a bunch as well as due to current compensating emission of the
secondary electrons. The methods, the models and the results of simulations are
presented.

</DOC>
<DOC>
<DOCNO> 116264 </DOCNO>
Gauge symmetry, chirality and parity violation in four-particle systems:


  Following recent work in search of a universal function (Van Hooydonk, Eur J
Inorg Chem, 1999, 1617), we test symmetric potentials for reproducing molecular
potential energy curves (PECs). For a bond, a four-particle system, charge
inversion is the key to explain this shape generically. A parity adapted
Hamiltonian reduces from ten to two terms. The analytical perturbed Coulomb
function scales attractive and repulsive branches of 13 PECs (HH, HF, LiH, KH,
AuH, LiLi, LiF, KLi, NaCs, RbRb,RbCs, CsCs and II) in a single straight line.
Turning points are reproduced with a deviation of 0.3 % (0.007 angstrom). At
the repulsive side, the deviation is 0.2 % (0.003 angstrom). The ab initio zero
molecular parameter function gives PECs of acceptable quality, just using
atomic ionisation energies. The function can be used as a model potential for
inverting energy levels. The theory may be tested with femtochemistry.
Reactions between hydrogen and anti-hydrogen, feasible in the near future, will
probably produce normal HH.

</DOC>
<DOC>
<DOCNO> 101672 </DOCNO>
L^2-invariants of locally symmetric spaces


  We explain how the Harish-Chandra Plancherel Theorem and results in relative
Lie algebra cohomology can be used in order to compute in a uniform way the
$L^2$-Betti numbers, the Novikov-Shubin invariants, and the $L^2$-torsion of
compact locally symmetric spaces thus completing results previously obtained by
Borel, Lott, Mathai, Hess and Schick. It turns out that the behaviour of these
invariants is essentially determined by the fundamental rank of the group of
isometries of the corresponding globally symmetric space. In particular, we
show the nonvanishing of the $L^2$-torsion whenever the fundamental rank is
equal to 1.

</DOC>
<DOC>
<DOCNO> 116429 </DOCNO>
Phase changes in 38 atom Lennard-Jones clusters. II: A parallel


  We study the 38-atom Lennard-Jones cluster with parallel tempering Monte
Carlo methods in the microcanonical and molecular dynamics ensembles. A new
Monte Carlo algorithm is presented that samples rigorously the molecular
dynamics ensemble for a system at constant total energy, linear and angular
momenta. By combining the parallel tempering technique with molecular dynamics
methods, we develop a hybrid method to overcome quasi-ergodicity and to extract
both equilibrium and dynamical properties from Monte Carlo and molecular
dynamics simulations. Several thermodynamic, structural and dynamical
properties are investigated for LJ$_{38}$, including the caloric curve, the
diffusion constant and the largest Lyapunov exponent. The importance of
insuring ergodicity in molecular dynamics simulations is illustrated by
comparing the results of ergodic simulations with earlier molecular dynamics
simulations.

</DOC>
<DOC>
<DOCNO> 117518 </DOCNO>
Superluminal Caustics of Close, Rapidly-Rotating Binary Microlenses


  The two outer triangular caustics (regions of infinite magnification) of a
close binary microlens move much faster than the components of the binary
themselves, and can even exceed the speed of light. When $\epsilon > 1$, where
$\epsilon c$ is the caustic speed, the usual formalism for calculating the lens
magnification breaks down. We develop a new formalism that makes use of the
gravitational analog of the Li\'enard-Wiechert potential. We find that as the
binary speeds up, the caustics undergo several related changes: First, their
position in space drifts. Second, they rotate about their own axes so that they
no longer have a cusp facing the binary center of mass. Third, they grow larger
and dramatically so for $\epsilon >> 1$. Fourth, they grow weaker roughly in
proportion to their increasing size. Superluminal caustic-crossing events are
probably not uncommon, but they are difficult to observe.

</DOC>
<DOC>
<DOCNO> 70881 </DOCNO>
Intercepts of the non-singlet structure functions


  Infrared evolution equations for small-$x$ behaviour of the non-singlet
structure functions $f_1^{NS}$ and $g_1^{NS}$ are obtained and solved in the
next-to-leading approximation, to all orders in $\alpha_s$, and including
running $\alpha_s$ effects. The intercepts of these structure functions, i.e.
the exponents of the power-like small-$x$ behaviour, are calculated. A detailed
comparison with the leading logarithmic approximation (LLA) and DGLAP is made.
We explain why the LLA predictions for the small-$x$ dependence of the
structure functions may be more reliable than the prediction for the $Q^2$
dependence in the range of $Q^2$ explored at HERA.

</DOC>
<DOC>
<DOCNO> 120380 </DOCNO>
Searches for astronomical neutrino sources and WIMPs with


  Searches for astronomical neutrino sources and weakly interactive massive
particles (WIMPs) using the Super-Kamiokande detector have been performed. We
select the neutrino-induced upward muon events for the first 4 years, which is
already the world largest data sample, and look for statistically significant
excesses compared to the atmospheric neutrino background. No excess has been
found so far. Limits of upward muon flux from various potential sources are
obtained. Also limits of upward muon flux due to annihilations of WIMPs in the
Earth core, the Sun and the Galactic center are obtained as a function of WIMP
masses.

</DOC>
<DOC>
<DOCNO> 178484 </DOCNO>
Limits on the low energy antinucleon-nucleus annihilations from the


  We show that the quantum uncertainty principle puts some limits on the
effectiveness of the antinucleon-nucleus annihilation at very low energies.
This is caused by the fact that the realization a very effective short-distance
reaction process implies information on the relative distance of the reacting
particles. Some quantitative predictions are possible on this ground, including
the approximate A-independence of antinucleon-nucleus annihilation rates.

</DOC>
<DOC>
<DOCNO> 7969 </DOCNO>
The low-energy scale of the periodic Anderson model


  Wilson's Numerical Renormalization Group method is used to study the
paramagnetic ground state of the periodic Anderson model within the dynamical
mean-field approach. For the particle-hole symmetric model, which is a Kondo
insulator, we find that the lattice Kondo scale T_0 is strongly enhanced over
the impurity scale T_K; T_0/T_K ~ exp(1/3I), where I is the Schrieffer-Wolff
exchange coupling. In the metallic regime, where the conduction band filling is
reduced from one, we find characteristic signatures of Nozi\`eres exhaustion
scenario, including a strongly reduced lattice Kondo scale, a significant
suppression of the states available to screen the f-electron moment, and a
Kondo resonance with a strongly enhanced height. However, in contrast to the
quantitative predictions of Nozi\`eres, we find that the T_0 ~ T_K with a
coefficient which depends strongly on conduction band filling.

</DOC>
<DOC>
<DOCNO> 116864 </DOCNO>
The Spallation Neutron Source (SNS) Linac RF System


  The SNS linac accelerates an average beam current of 2 mA to an energy of 968
MeV. The linac is pulsed at 60 Hz with an H- beam pulse of 1 ms. The first 185
Mev of the linac uses normal conducting cavities, and the remaining length of
the linac uses superconducting cavities. The linac operates at 402.5 MHz up to
87 MeV and then changes to 805 MHz for the remainder. This paper gives an
overview of the Linac RF system. The overview includes a description and
configuration of the high power RF components, the HV converter/modulator, and
the RF controls. Issues and tradeoffs in the RF system will be discussed,
especially with regards to the use of pulsed superconducting cavities.

</DOC>
<DOC>
<DOCNO> 85121 </DOCNO>
Chiral Superconducting Membranes


  We develop the dynamics of the chiral superconducting membranes in a
geometric approach either making a Lagrangian description and a Hamiltonian
point of view. Besides, we show the equivalence of the resulting descriptions
to the one known Dirac-Nambu-Goto (DNG) case. Integrability for chiral string
model is obtained using a proposed light-cone gauge. In a similar way, domain
walls are integrated by means of a special ansatz. We compare the results with
recently works appeared in the literature.

</DOC>
<DOC>
<DOCNO> 69022 </DOCNO>
$K_L\to\gamma\nu\bar{\nu}$ in the Light Front Model


  We study the CP conserving and violating contributions to the decay of
$\knng$ in the standard model. In our analysis, we use the form factors for
$K\to\gamma$ transitions calculated directly in the entire physical range of
momentum transfer within the light front model. We find that the branching
ratios for the CP conserving and violating parts are about $1.0\times 10^{-13}$
and $1.5\times 10^{-15}$, respectively.

</DOC>
<DOC>
<DOCNO> 11815 </DOCNO>
Theory and Experiment on the Surface Photovoltage Diffusion Length


  A simplified theoretical model for the constant-magnitude steady-state
surface photovoltage (SPV) technique is developed. Emphasis is placed on the
determination of the minority carrier diffusion length L in the particular case
for which the sample thickness is quite lower than the true value of L. The
model is derived from the theoretical basis with the assumption that incidental
light flux varies linearly in the explored range. This model fits very well to
experimental data points obtained from both FZ and CZ mono-silicon crystals. We
showed that in the case of thin wafers, SPV technique is not adapted to L
measurements. It leads only to extracting a short length proportional to the
sample thickness. However, if the recombination velocities and the minority
carrier diffusion coefficient are known, then we could reach the true value of
L by a computer calculation.

</DOC>
<DOC>
<DOCNO> 178943 </DOCNO>
Nuclear Molecular Halo: Threshold Effect or Soft Dipole in 11Li?


  The observation of large E1 strength near threshold in the electromagnetic
dissociation of 11Li poses a fundamental question: Is the large E1 strength due
to the threshold or is it due to a low lying E1 state? Such molecular cluster
states were observed in 18O and in several nuclei near the drip line. We
discuss the nature of the "threshold effect" as well as review the situation in
Molecular (and Particle Physics) where such Molecular States are observed near
the dissociation limit. We suggest that the situation in 11Li is reminiscent of
the argon-benzene molecule where the argon atom is loosely bound by a
polarization (van der Waals) mechanism and thus leads to a very extended object
lying near the dissociation limit. Such states are also suggested to dominate
the structure of mesons [a_0(980), f_0(975)] and baryons [Lambda(1405)] with
proposed Kaon molecular structure (e.g. by Dalitz) near threshold. The
inspection of such states throughout Physics allows us to gain insight into
this phenomenon and suggest that a new collective Molecular Dipole Degree of
Freedom plays a major role in the structure of hadrons (halo nuclei, mesons and
baryons), and that quantitative tools such as the E1 Molecular Sum Rule are
useful for elucidating the nature of the observed low lying E1 strength in halo
nuclei.

</DOC>
<DOC>
<DOCNO> 71394 </DOCNO>
Resummation of the Divergent Perturbation Series for a Hydrogen Atom in


  We consider the resummation of the perturbation series describing the energy
displacement of a hydrogenic bound state in an electric field (known as the
Stark effect or the LoSurdo-Stark effect), which constitutes a divergent formal
power series in the electric field strength. The perturbation series exhibits a
rich singularity structure in the Borel plane. Resummation methods are
presented which appear to lead to consistent results even in problematic cases
where isolated singularities or branch cuts are present on the positive and
negative real axis in the Borel plane. Two resummation prescriptions are
compared: (i) a variant of the Borel-Pade resummation method, with an
additional improvement due to utilization of the leading renormalon poles (for
a comprehensive discussion of renormalons see [M. Beneke, Phys. Rep. vol. 317,
p. 1 (1999)]), and (ii) a contour-improved combination of the Borel method with
an analytic continuation by conformal mapping, and Pade approximations in the
conformal variable. The singularity structure in the case of the LoSurdo-Stark
effect in the complex Borel plane is shown to be similar to (divergent)
perturbative expansions in quantum chromodynamics.

</DOC>
<DOC>
<DOCNO> 8972 </DOCNO>
Glassy Dynamics in a Frustrated Spin System: Role of Defects


  In an effort to understand the glass transition, the kinetics of a spin model
with frustration but no quenched randomness has been analyzed. The
phenomenology of the spin model is remarkably similiar to that of structural
glasses. Analysis of the model suggests that defects play a major role in
dictating the dynamics as the glass transition is approached.

</DOC>
<DOC>
<DOCNO> 122167 </DOCNO>
Searching for Supersymmetric Dark Matter- The Modulation Effect Due to


  The detection of the theoretically expected dark matter is central to
particle physics and cosmology. Current fashionable supersymmetric models
provide a natural dark matter candidate which is the lightest supersymmetric
particle (LSP). The theoretically obtained event rates are usually very low or
even undetectable. So the experimentalists would like to exploit the modulation
effect. In the present paper we study a specific class of non-isothermal models
involving flows of caustic rings. We find that the modulation effect arising
from such models is smaller than that predicted by the isothermal models.

</DOC>
<DOC>
<DOCNO> 69159 </DOCNO>
Impact Parameter Dependent Parton Distributions and Off-Forward Parton


  It is shown that off-forward parton distributions for $\zeta =0$, i.e. where
the initial and final state differ only in their transverse momenta, can be
interpreted as a simultaneous measurement of the longitudinal momentum and
transverse position (impact parameter) of partons in the infinite momentum
frame.

</DOC>
<DOC>
<DOCNO> 11222 </DOCNO>
Tunneling through an Anderson impurity between superconductors


  We consider an Anderson impurity (A) weakly connected to a superconducting
electrode (S) on one side and a superconducting or a normal metal electrode (N)
on the other side. A general path integral formalism is developed and the
response of SAN and SAS junctions to a constant voltage bias V is elucidated,
using a combination of the Keldysh technique (to handle non-equilibrium
effects) and a dynamical mean field approximation (to handle repulsive Hubbard
interactions). An interesting physics is exposed at sub-gap voltages ($eV <
\Delta$ for SAN and $eV < 2 \Delta$ for SAS). For an SAN junction, Andreev
reflection is strongly affected by Coulomb interaction. For superconductors
with p-wave symmetry the junction conductance exhibits a remarkable peak at $eV
< \Delta$, while for superconductors with s-wave symmetric pair potential the
peak is shifted towards the gap edge $eV=\Delta$ and strongly suppressed if the
Hubbard repulsive interaction increases.Electron transport in SAS junctions is
determined by an interplay between multiple Andreev reflection (MAR) and
Coulomb effects. For s-wave superconductors the usual peaks in the conductance
that originate from MAR are shifted by interaction to larger values of V. They
are also suppressed as the Hubbard interaction strength grows. For p-wave
superconductors the sub-gap current is much larger and the I-V characteristics
reveal a new feature, namely, a peak in the current resulting from a mid-gap
bound state in the junction.

</DOC>
<DOC>
<DOCNO> 122091 </DOCNO>
Solar variability and climate


  Recent precise observations of solar global parameters are used to calibrate
an upgraded solar model which takes into account magnetic fields in the solar
interior. Historical data about sunspot numbers (from 1500 to the present) and
solar radius changes (between 1715 and 1979) are used to compute solar
variability on years to centuries timescales. The results show that although
the 11 year variability of the total irradiance is of the order of 0.1%,
additional, longer lived changes of the order of 0.1% may have occurred in the
past centuries. These could, for example, account for the occurrence of climate
excursions such as little ice ages.

</DOC>
<DOC>
<DOCNO> 117329 </DOCNO>
Measurements of Spatial Resolution of ATLAS Pixel Detectors


  Standard as well as irradiated silicon pixel detectors developed for the
ATLAS experiment were tested in a beam. Digital and analog resolutions were
determined comparing the positions measured by a microstrip telescope and by
the pixel detector. Digital resolutions of 10 um and analog resolutions of 6 um
(before irradiation) and 10 um (after irradiation) are obtained without
subtracting the error on the position determined by the telescope.

</DOC>
<DOC>
<DOCNO> 84657 </DOCNO>
LISA observations of massive black holes binaries using post-Newtonian


  We consider LISA observations of in-spiral signals emitted by massive black
hole binary systems in circular orbit and with negligible spins. We study the
accuracy with which the source parameters can be extracted from the data
stream. We show that the use of waveforms retaining post-Newtonian corrections
not only to the phase but also the amplitude can drastically improve the
estimation of some parameters.

</DOC>
<DOC>
<DOCNO> 121208 </DOCNO>
The Starburst-Interstellar Medium Interaction of NGC 1569 I. Location


  We present the detection of He II sources in the Im galaxy NGC 1569 from HST
WFPC2 imagery. Out of the fifteen detections, seven were Wolf-Rayet stars, five
were stellar clusters with associated He II emission, and three were sources of
unknown origin. The detected Wolf-Rayet stars' colors and magnitudes are
similar to Large Magellanic Cloud late-type WN stars. The physical origin of
the other He II sources are discussed. We conclude that the equivalent of
51+/-19 WNL stars have been detected in NGC 1569, and we have estimated the
total Wolf-Rayet population in NGC 1569 as 78+/-51. These numbers are compared
with the Wolf-Rayet stellar populations in the SMC, LMC, Milky Way, and other
starburst galaxies relative to their luminosities, dynamical masses, and
ionized gas masses. Previous to this study, Wolf-Rayet stars in NGC 1569 were
not detected using ground-based imagery, but were only indicated through
longslit spectroscopy. This is the first time the exact locations of the
Wolf-Rayet stars in this nearby, well-studied, "post-starburst" galaxy have
been determined.

</DOC>
<DOC>
<DOCNO> 169908 </DOCNO>
Contracting the Wigner-Kernel of a Spin to the Wigner-Kernel of a


  A general relation between the Moyal formalisms for a spin and a particle is
established. Once the formalism has been set up for a spin, the phase-space
description of a particle is obtained from the `contraction' of the group of
rotations to the group of translations. This is shown by explicitly contracting
a spin Wigner-kernel to the Wigner kernel of a particle. In fact, only one out
of 2^{2s} different possible kernels for a spin shows this behaviour.

</DOC>
<DOC>
<DOCNO> 10036 </DOCNO>
Densification effects on the Boson peak in vitreous silica: a


  We perform classical molecular-dynamics simulation to study the effect of
densification on the vibrational spectrum of a model silica glass. We
concentrate this study on the so-called Boson peak and compare our results,
obtained from a direct diagonalization of the dynamical matrix, with
experimental Raman data. We show that, upon densification, the position of the
Boson peak shifts towards higher frequencies while its magnitude decreases
which is in agreement with a recent experimental study.

</DOC>
<DOC>
<DOCNO> 102840 </DOCNO>
Probability and Geometry on some Noncommutative Manifolds


  In a noncommutative torus, effect of perturbation by inner derivation on the
associated quantum stochastic process and geometric parameters like volume and
scalar curvature have been studied. Cohomological calculations show that the
above perturbation produces new spectral triples. Also for the Weyl
C^*-algebra, the Laplacian associated with a natural stochastic process is
obtained and associated volume form is calculated. Keywords: noncommutative
torus, Laplacian, Dixmier trace, quantum stochastic process.

</DOC>
<DOC>
<DOCNO> 13066 </DOCNO>
On the Best Quadratic Approximation in Feynman's Path Integral Treatment


  The best quadratic approximation to the retarded polaron action due to
Adamowski {\it et al.} and Saitoh is investigated numerically for a wide range
of coupling constants. The non-linear variational equations are solved
iteratively with an efficient method in order to obtain the ground state energy
and the effective mass of the polaron. The virial theorem and expansions for
small and large couplings are used to check the high accuracy of the numerical
results. Only small improvements over Feynman's (non-optimal) results are
observed. For a moving polaron it is shown that the most general quadratic
trial action may contain anisotropic terms which, however, do not lead to
improvements for the ground state energy and effective mass.

</DOC>
<DOC>
<DOCNO> 150925 </DOCNO>
On noncommutative and commutative equivalence for BFYM theory : :


  BFYM on commutative and noncommutative ${\mathbb{R}}^4$ is considered and a
Seiberg-Witten gauge-equivalent transformation is constructed for these
theories. Then we write the noncommutative action in terms of the ordinary
fields and show that it is equivalent to the ordinary action up to higher
dimensional gauge invariant terms.

</DOC>
<DOC>
<DOCNO> 99309 </DOCNO>
Incidence algebras of simplicial complexes


  With any locally finite partially ordered set $K$ its incidence algebra
$\Omega(K)$ is associated. We shall consider algebras over fields with
characteristic zero. In this case there is a correspondence $K \leftrightarrow
\Omega(K)$ such that the poset $K$ can be reconstructed from its incidence
algebra up to an isomorphism --- due to Stanley theorem. In the meantime, a
monotone mapping between two posets in general induces no homomorphism of their
incidence algebras.
  In this paper I show that if the class of posets is confined to simplicial
complexes then their incidence algebras acquire the structure of differential
moduli and the correspondence $K\leftrightarrow\Omega(K)$ is a contravariant
functor.

</DOC>
<DOC>
<DOCNO> 12407 </DOCNO>
Time reparametrization group and the long time behaviour in quantum


  We study the long time dynamics of a quantum version of the
Sherrington-Kirkpatrick model. Time reparametrizations of the dynamical
equations have a parallel with renormalization group transformations, and
within this language the long time behaviour of this model is controlled by a
reparametrization group (R$_p$G) fixed point of the classical dynamics. The
irrelevance of the quantum terms in the dynamical equations in the aging regime
explains the classical nature of the violation of the fluctuation-dissipation
theorem.

</DOC>
<DOC>
<DOCNO> 11741 </DOCNO>
Large Orbital Magnetic Moment in Febr2


  Magnetic moment of the Fe2+ ion in FeBr2 has been calculated to be 4.32 mB in
the magnetically-ordered state at 0 K. It is composed from the spin moment of
3.52 mB and the orbital moment of +0.80 mB. These calculations show that for
the meaningful analysis of e-m properties of FeBr2 the spin-orbit coupling is
essentially important and that the orbital moment is largely unquenched.

</DOC>
<DOC>
<DOCNO> 170034 </DOCNO>
Quantum jumps in backaction evasion measurements of a light field


  Backaction evasion measurements of a quadrature component of the light field
vacuum necessarily induce quantum jumps in the photon number. The correlation
between measurement results and quantum jump events reveals fundamental
nonclassical aspects of quantization.

</DOC>
<DOC>
<DOCNO> 68560 </DOCNO>
Radiative correction of the correlator for (0^{++},1$^{-+}$) light


  We calculate the radiative corrections to the current-current correlator of
the hybrid current $g\bar q(x)\gamma_{\nu}iG_{\mu\nu}^aT^aq(x)$. Based on this
new result we use the QCD sum rule approach to estimate lower bounds on the
masses of the $J^{PC}$=$1^{-+}$ and $0^{++}$ light hybrids.

</DOC>
<DOC>
<DOCNO> 120479 </DOCNO>
The Influence of Interactions and Minor Mergers on the Structure of


  We present the second part of a detailed statistical study focussed on the
effects of tidal interactions and minor mergers on the radial and vertical disk
structure of spiral galaxies. In the first part we reported on the sample
selection, observations, and applied disk models. In this paper the results are
presented, based on disk parameters derived from a sample of 110
highly-inclined/edge-on galaxies. This sample consists of two subsamples of 49
interacting/merging and 61 non-interacting galaxies. Additionally, 41 of these
galaxies were observed in the NIR. We find significant changes of the disk
structure in vertical direction, resulting in ~1.5 times larger scale heights
and thus vertical velocity dispersions. The radial disk structure,
characterized by the cut-off radius and the scale length, shows no
statistically significant changes. Thus, the ratio of radial to vertical scale
parameters, h/z0, is ~1.7 times smaller for the sample of interacting/merging
galaxies. The total lack of typical flat disk ratios (h/z0)>7 in the latter
sample implies that vertical disk heating is most efficient for (extremely)
thin disks. Statistically nearly all galactic disks in the sample (93%) possess
non-isothermal vertical luminosity profiles like the sech (60%) and exp (33%)
distribution, independent of the sample and passband investigated. This
indicates that, in spite of tidal perturbations and disk thickening, the
initial vertical distribution of disk stars is not destroyed by interactions or
minor mergers.

</DOC>
<DOC>
<DOCNO> 117281 </DOCNO>
Modelling horizontal and vertical concentration profiles of ozone and


  A Lagrangian column model has been developed to simulate the mean (monthly
and annual) three-dimensional structure in ozone and nitrogen oxides
concentrations in the boundary layer within and immediately around an urban
area. Short time-scale photochemical processes of ozone, as well as emissions
and deposition to the ground are simulated. The results show that the average
surface ozone concentration in the urban area is lower than the surrounding
rural areas by typically 50%. Model results are compared with observations.

</DOC>
<DOC>
<DOCNO> 39662 </DOCNO>
Effects Of Kaluza-Klein Excited W On Single Top Quark Production At


  In extra dimension theories if the gauge bosons of the standard model
propagate in the bulk of the extra dimensions then they will have Kaluza-Klein
excitations that can couple to the standard model fermions. In this paper we
study the effects of the first excited Kaluza-Klein mode of the W on single
top production at the Tevatron. We find that the cross section for the single
top production can be significantly reduced if the mass of the first
Kaluza-Klein excited $W \sim 1$ TeV. Hence, a measurement of the single top
production cross section smaller than the standard model prediction would not
necessarily imply $V_{tb} <1$ or evidence of extra generation(s) of fermions
mixed with the third generation.

</DOC>
<DOC>
<DOCNO> 85235 </DOCNO>
Naked Reissner-Nordstr\"{o}m Singularities and the Anomalous Magnetic


  We study the problem of the quantization of the massive charged Dirac field
on a naked Reissner-Nordstr\"{o}m background. We show that the introduction of
an anomalous magnetic moment for the electron field allows a well--defined
quantum theory for the one-particle Dirac Hamiltonian, because no boundary
condition on the singularity is required. This means that would-be higher order
corrections can play an essential role in determining physics on the naked
Reissner-Nordstr\"{o}m background and that a non-perturbative approach is
required. Moreover, we show that bound states for the Dirac equation are
allowed. Various aspects of the physical picture emerging from our study are
also discussed, such as the possibility to obtain exotic atomic systems, the
formation of black holes by electronic capture and some interesting consistency
problems involving quantum gravity.

</DOC>
<DOC>
<DOCNO> 102685 </DOCNO>
Global knot theory in F^2 x R


  We introduce a special class of knots, called global knots, in F^2 x R and we
construct new isotopy invariants, called T-invariants, for global knots.
  Some T-invariants are of finite type but they cannot be extracted from the
generalized Kontsevitch integral (which is consequently not the universal
invariant of finite type for the restricted class of global knots).
  We prove that T-invariants separate all global knots of a certain type. As a
corollary, we prove the non-invertibility of some links in S^3 without making
any use of the link group.

</DOC>
<DOC>
<DOCNO> 8057 </DOCNO>
Auger decay, Spin-exchange, and their connection to Bose-Einstein


  In view of the recent experiments of O'Hara, et al. on excitons in Cu_2O, we
examine the interconversion between the angular-momentum triplet-state excitons
and the angular-momentum singlet-state excitons by a spin-exchange process
which has been overlooked in the past. We estimate the rate of this
particle-conserving mechanism and find a substantially higher value than the
Auger process considered so far. Based on this idea, we give a possible
explanation of the recent experimental observations, and make certain
predictions, with the most important being that the singlet-state excitons in
Cu_2O is a very serious candidate for exhibiting the phenomenon of
Bose-Einstein condensation.

</DOC>
<DOC>
<DOCNO> 101883 </DOCNO>
Time Quasi-periodic unbounded perturbations of Schr\"odinger operators


  We eliminate by KAM methods the time dependence in a class of linear
differential equations in $\ell^2$ subject to an unbounded, quasi-periodic
forcing. This entails the pure-point nature of the Floquet spectrum of the
operator $ H_0+\epsilon P(\om t)$ for $\epsilon$ small. Here $H_0$ is the
one-dimensional Schr\"odinger operator $p^2+V$, $V(x)\sim |x|^{\alpha}, \alpha
>2$ for $|x|\to\infty$, the time quasi--periodic perturbation $P$ may grow as
$\displaystyle |x|^{\beta}, \beta <(\alpha-2)/{2}$, and the frequency vector
$\omega$ is non resonant. The proof extends to infinite dimensional spaces the
result valid for quasiperiodically forced linear differential equations and is
based on Kuksin's estimate of solutions of homological equations with non
constant coefficients.

</DOC>
<DOC>
<DOCNO> 121542 </DOCNO>
Star Formation in Galaxies between 0.7 < z < 1.8


  We present an analysis of the star formation rate in galaxies between
0.7<z<1.8 using Near Infrared Camera and Multi-Object Spectrograph (NICMOS)
grism spectral observations. We detect 163 galaxies in an area of ~4.4 square
arcminutes, 37 of which show possible H-alpha emission. We extend the observed
H-alpha luminosity function (LF) in this redshift range to luminosities a
factor of two fainter than earlier work, and are consistent in the region of
overlap. Using the H-alpha LF, we estimate a star formation rate (SFR) density
in this redshift range of 0.166 M_sun/yr/Mpc^3 (H0=75 km/s/Mpc), consistent
with other estimates based on emission lines, and supporting the order of
magnitude increase in SFR density between z=0 and z=1. Our measurement of SFR
density is a factor of ~2-3 greater than that estimated from UV data,
comparable to the factor observed locally, implying little evolution in the
relative extinctions between UV and H-alpha out to z~1.3.

</DOC>
<DOC>
<DOCNO> 118034 </DOCNO>
A deep search for the optical counterpart to the anomalous X-ray pulsar


  We present Keck R and I band images of the field of the anomalous X-ray
pulsar 1E 2259+58.6. We derive an improved X-ray position from archival ROSAT
HRI observations by correcting for systematic (boresight) errors. Within the
corresponding error circle, no object is found on the Keck images, down to
limiting magnitudes R = 25.7 and I = 24.3. We discuss the constraints imposed
by these limits, and conclude that it is unlikely that 1E 2259+58.6 is powered
by accretion from a disk, irrespective of whether it is in a binary or not,
unless the binary is extremely compact.

</DOC>
<DOC>
<DOCNO> 122080 </DOCNO>
Pressure- and magnetic shear- driven instabilities in rotating MHD jets


  We derive new stability criteria for purely MHD instabilities in rotating
jets, in the framework of the ballooning ordering expansion. Quite
unexpectedly, they involve a term which is linear in the magnetic shear. This
implies that cylindrical configurations can be destabilized by a negative
magnetic shear as well as by a favorable equilibrium pressure gradient, in
distinction with the predictions of Suydam's stability criterion, which
suggests on the contrary that the shear is always stabilizing.
  We have used these criteria to establish sufficient conditions for
instability. In particular, the magnetic shear can always destabilize jets with
vanishing current density on the axis, a feature which is generically found in
jets which are launched from an accretion disk. We also show that standard
nonrotating jet models (where the toroidal field dominates the poloidal one),
which are known to be unstable, are not stabilized by rotation, unless the
plasma $\beta$ parameter and the strength of the rotation forces are both close
to the limit allowed by the condition of radial equilibrium.
  The new magnetic shear-driven instability found in this paper, as well as the
more conventional pressure-driven instability, might provide us with a
potential energy source for the particle acceleration mechanisms underlying the
high energy emission which takes place in the interior of AGN jets.

</DOC>
<DOC>
<DOCNO> 121221 </DOCNO>
A Broad Search for Counterrotating Gas and Stars: Evidence for Mergers


  We measure the frequency of bulk gas-stellar counterrotation in a sample of
67 galaxies drawn from the Nearby Field Galaxy Survey, a broadly representative
survey of the local galaxy population down to M_B-15. We detect 4
counterrotators among 17 E/S0's with extended gas emission (24% +8 -6). In
contrast, we find no clear examples of bulk counterrotation among 38 Sa-Sbc
spirals, although one Sa does show peculiar gas kinematics. This result implies
that, at 95% confidence, no more than 8% of Sa-Sbc spirals are bulk
counterrotators. Among types Sc and later, we identify only one possible
counterrotator, a Magellanic irregular. We use these results together with the
physical properties of the counterrotators to constrain possible origins for
this phenomenon.

</DOC>
<DOC>
<DOCNO> 151680 </DOCNO>
Decay Modes of Highly Excited String States and Kerr Black Holes


  We consider four-graviton scattering in Type II string theory on one-loop
level in the large centre of mass energy M^2 limit. We extract from it an
explicit integral expression for the full string theory corrections to the
imaginary part of the mass-shift and the lifetime of a massive state with the
highest allowed spin J=2M^2+2. We find a decay rate that is up to log M
corrections of order 1 in string units, times g_s^2. We also find that the
dominant decay mode corresponds to the emission of light particles, whereas the
decay into two massive or two massless states is exponentially suppressed. We
discuss the relation of our results to quantum gravity aspects of a Kerr Black
Hole.

</DOC>
<DOC>
<DOCNO> 174601 </DOCNO>
Quest for double beta decay of 160-Gd and Ce isotopes


  The double beta decay study of 160-Gd has been performed in the Solotvina
Underground Laboratory with the help of Gd_2SiO_5(Ce) crystal scintillator
(volume 95 cc). The background of the detector in the vicinity of the 2 beta
energy of 160-Gd was reduced to 1.0 cpd/keV kg. The new improved half-life
limits have been established for neutrinoless 2 beta decay of 160-Gd to the
ground and first excited levels of 160-Dy: T1/2 > 2.3(1.3)E21 yr at 68%(90%)
C.L. The T1/2 bounds have been also set for two neutrino mode as well as for 2
beta decay with Majorons emission. Also the limits were established for
different 2 beta decay processes in 136-Ce, 138-Ce and 142-Ce.

</DOC>
<DOC>
<DOCNO> 70312 </DOCNO>
Viable Supersymmetric Models with an Inverted Scalar Mass Hierarchy at


  Supersymmetric models with an inverted mass hierarchy (IMH: multi-TeV first
and second generation matter scalars, and sub-TeV third generation and Higgs
scalars) have been proposed to ameliorate phenomenological problems arising
from flavor changing neutral currents (FCNCs) and CP violating processes, while
satisfying conditions of naturalness. Models with an IMH already in place at
the GUT scale have been shown to be constrained in that for many model
parameter choices, the top squark squared mass is driven to negative values. We
delineate regions of parameter space where viable models with a GUT scale IMH
can be generated. We find that larger values of GUT scale first and second
generation scalar masses act to suppress third generation scalars, leading to
acceptable solutions if GUT scale gaugino masses are large enough. We show
examples of viable models and comment on their characteristic features. For
example, in these models the gluino mass is bounded from below, and effectively
decouples, whilst third generation scalars remain at sub-TeV levels. While
possibly fulfilling criteria of naturalness, these models present challenges
for detection at future pp and e^+e^- collider experiments.

</DOC>
<DOC>
<DOCNO> 10884 </DOCNO>
Controlling chaos in diluted networks with continuous neurons


  Diluted neural networks with continuous neurons and nonmonotonic transfer
function are studied, with both fixed and dynamic synapses. A noisy stimulus
with periodic variance results in a mechanism for controlling chaos in neural
systems with fixed synapses: a proper amount of external perturbation forces
the system to behave periodically with the same period as the stimulus.

</DOC>
<DOC>
<DOCNO> 69245 </DOCNO>
The impact of LEP 2 data on possible anomalous enhancements of Re e'/e


  It has been shown in the past that the real part of the e'/e ratio is
particularly sensitive to anomalous gauge couplings that modify the Standard
Model Lagrangian. Due to the loose bounds on these couplings coming from low
energy processes and to the poor sensitivity of hadron colliders to couplings
such as $\Delta g_Z$, it has been argued that anomalous couplings could still
produce an enhancement of Re e'/e bringing this observable closer to the
experimental value obtained by KTeV, NA31 and NA48. The impact of the new
measurements done at LEP2 in these years is discussed and new severe
constraints to this hypothesis are determined.

</DOC>
<DOC>
<DOCNO> 99927 </DOCNO>
On the cohomology ring of the moduli space of Higgs bundles I:


  The moduli space of stable vector bundles on a Riemann surface is smooth when
the rank and degree are coprime, and is diffeomorphic to the space of unitary
connections of central constant curvature. A classic result of Newstead and
Atiyah-Bott asserts that its rational cohomology ring is generated by the
universal classes, that is, by the Kunneth components of the Chern classes of
the universal bundle.
      This paper studies the larger, non-compact moduli space of Higgs bundles,
as introduced by Hitchin and Simpson, with values in the canonical bundle K.
This is diffeomorphic to the space of all connections of central constant
curvature, whether unitary or not. The main result of the paper is that the
rational cohomology ring of this space is again generated by universal classes.
      The spaces of Higgs bundles with values in K(n) for n > 0 turn out to be
essential to the story. Indeed, we show that their direct limit has the
homotopy type of the classifying space of the gauge group, and hence has
cohomology generated by universal classes.
      A companion paper treats the problem of finding relations between these
generators in the rank 2 case.

</DOC>
<DOC>
<DOCNO> 102021 </DOCNO>
The spectral set conjecture and multiplicative properties of roots of


  We obtain new partial results supporting the spectral set conjecture in
dimension 1.

</DOC>
<DOC>
<DOCNO> 12929 </DOCNO>
Statistics of the occupation time for a class of Gaussian Markov


  We revisit the work of Dhar and Majumdar [Phys. Rev. E 59, 6413
(1999)] on the limiting distribution of the temporal mean
$M_{t}=t^{-1}\int_{0}^{t}du \sign y_{u}$, for a Gaussian Markovian process
$y_{t}$ depending on a parameter $\alpha $, which can be interpreted as
Brownian motion in the scale of time $t^{\prime}=t^{2\alpha}$. This quantity,
for short the mean `magnetization', is simply related to the occupation time of
the process, that is the length of time spent on one side of the origin up to
time t. Using the fact that the intervals between sign changes of the process
form a renewal process in the time scale t', we determine recursively the
moments of the mean magnetization. We also find an integral equation for the
distribution of $M_{t}$. This allows a local analysis of this distribution in
the persistence region $(M_t\to\pm1)$, as well as its asymptotic analysis in
the regime where $\alpha$ is large. We finally put the results thus found in
perspective with those obtained by Dhar and Majumdar by another method, based
on a formalism due to Kac.

</DOC>
<DOC>
<DOCNO> 178391 </DOCNO>
Production of \phi Mesons in Near-Threshold \pi N and N N Reactions


  We analyze the production of $\phi$ mesons in $\pi N$ and NN reactions in the
near-threshold region, using throughout the conventional ``non-strange''
dynamics based on such processes which are allowed by the non-ideal
$\omega-\phi$ mixing. We show that the occurrence of the direct $\phi NN$
interaction may show up in different unpolarized and polarization observables
in $\pi N\to N\phi$ reactions. We find a strong non-trivial difference between
observables in the reactions $pp\to pp\phi$ and $pn\to pn\phi$ caused by the
different role of the spin singlet and triplet states in the entrance channel.
A series of predictions for the experimental study of this effect is presented.

</DOC>
<DOC>
<DOCNO> 40208 </DOCNO>
Structure Functions at Very High Q^2 From HERA


  Measurements of Deep-Inelastic Neutral and Charged current interactions are
presented in lepton proton scattering at HERA. The measurements are obtained
from taken during 1996 to 1999 and consists of $30 \rm{pb^{-1}}$ of $e^+p$ and
$16 \rm{pb^{-1}}$ of $e^-p$ data. The addition of the new high statistics
electron data with the positron data allows the first extraction of the parity
violating structure function $xF_3$ and tests of high-$Q^2$ electroweak effects
of the heavy bosons $Z^0$ and $W$ are observed and found to be consistent with
the Standard Model expectation.

</DOC>
<DOC>
<DOCNO> 10893 </DOCNO>
Partially filled stripes in the two dimensional Hubbard model: statics


  The internal structure of stripes in the two dimensional Hubbard model is
studied by going beyond the Hartree-Fock approximation. Partially filled
stripes, consistent with experimental observations, are stabilized by quantum
fluctuations, included through the Configuration Interaction method. Hopping of
short regions of the stripes in the transverse direction is comparable to the
bare hopping element. The integrated value of $n_{\bf \vec{k}}$ compares well
with experimental results.

</DOC>
<DOC>
<DOCNO> 117276 </DOCNO>
Time dependent energy absorption of atomic clusters from an intense


  For the energy absorption of atomic clusters as a function of the laser pulse
duration we find a similar behavior as it has been observed for metallic
clusters [K\"oller et al., Phys. Rev. Lett. {\bf 82}, 3783 (1999)]. In both
situations there exists an optimum radius $R_{o}$ of the cluster for energy
absorption. In the metallic case the existence of $R_{o}$ has been interpreted
as a consequence of the collective oscillation of a delocalized electron cloud
in resonance with the laser frequency. Here, we give evidence that in the
atomic cluster the origin of $R_{o}$ is very different. Based on field assisted
tunneling it can be related to the phenomenon of enhanced ionization as it
occurs in small molecules. The dependence of $R_{o}$ on the laser frequency
turns out to be the key quantity to distinguish the processes.

</DOC>
<DOC>
<DOCNO> 102284 </DOCNO>
On the Fu/v cik spectrum with indefinite weights


  This paper is devoted to the study of the Fu/v cik spectrum with indefinite
weights in the one-dimensional case.

</DOC>
<DOC>
<DOCNO> 11422 </DOCNO>
The Charge-Spin Separated Fermi Fluid in the High Tc Cuprates: A Quantum


  We find experimental evidence for spin-charge separation in all four relevant
phases of the cuprates. It is argued that this phenomenon serves to protect the
properties of the cuprates from the effects of impurities and phonons.

</DOC>
<DOC>
<DOCNO> 101572 </DOCNO>
An affine analogue of the Hartman-Nirenberg cylinder theorem


  Let X be a smooth, complete, connected submanifold of dimension n < N in a
complex affine space A^N (C), and r is the rank of its Gauss map \gamma, \gamma
(x) = T_x (X). The authors prove that if 2 \leq r \leq n - 1, N - n \geq 2, and
in the pencil of the second fundamental forms of X, there are two forms
defining a regular pencil all eigenvalues of which are distinct, then the
submanifold X is a cylinder with (n-r)-dimensional plane generators erected
over a smooth, complete, connected submanifold Y of rank r and dimension r.
This result is an affine analogue of the Hartman-Nirenberg cylinder theorem
proved for X \subset R^{n+1} and r = 1. For n \geq 4 and r = n - 1, there exist
complete connected submanifolds X \subset A^N (C) that are not cylinders.

</DOC>
<DOC>
<DOCNO> 121279 </DOCNO>
The Impact of the NACRE Compilation on the Big Bang Nucleosynthesis


  We update the Big Bang Nucleosynthesis (BBN) calculations on the basis of the
recent NACRE compilation of reaction rates. We estimate the uncertainties
related to the nuclear reaction rates on the abundances of D, 3He, 4He, 6Li,
7Li, 9Be, 10B and 11B of cosmological and astrophysical interest. We use
lithium as the main indicator of the baryon density of the Universe, rather
than deuterium.

</DOC>
<DOC>
<DOCNO> 85479 </DOCNO>
Cosmological Consequences of Conformal General Relativity


  We consider cosmological consequences of a conformal-invariant unified theory
which is dynamically equivalent to general relativity and is given in a space
with the geometry of similarity. We show that the conformal-invariant theory
offers new explanations for to such problems as the arrow of time, initial
cosmic data, dark matter and accelerating evolution of the universe in the dust
stage.

</DOC>
<DOC>
<DOCNO> 116626 </DOCNO>
Atom Interference using microfabricated structures


  Atom density profile arising in the atomic beam after passing through the one
or two microfabricated structures (MS) is considered. Two limiting cases the
beam with large and small angular divergence are considered. An equivalence of
the considerations based on the Fresnel-Kirchhoff theory of diffraction and on
the atomic recoil-effect is established. Higher order gratings' profiles
produced in the collinear beam owing to the atomic Talbot effect are
calculated. For an atomic beam with large angular divergence, two regimes of
atoms' scattering off the MS, classical and quantum, are analyzed. For
classical scattering from two MSs, the atomic density periodic modulation
focusses at the echo points owing to the shadow effect. Elaborated simple
geometric interpretation of the echo-effect. Dephasing-rephasing processes
induced by two MSs having rational ratio of their periods are fully classified.
Positions and profiles of the higher order gratings are calculated. Gratings'
deformations caused by the quantum scattering are included. In this case,
corresponding to the atomic Talbot-Lau effect, for a distance between fields
equal to 1/n part of the Talbot distance, one compresses n times the grating
caused by the shadow effect.

</DOC>
<DOC>
<DOCNO> 119810 </DOCNO>
Iterative map-making for scanning experiments


  We describe here an iterative method for jointly estimating the noise power
spectrum from a scanning experiment's time-ordered data, together with the
maximum-likelihood map. We test the robustness of this method on simulated
datasets with colored noise, like those of bolometer receivers in CMB
experiments.

</DOC>
<DOC>
<DOCNO> 8637 </DOCNO>
Surface Hardening and Self-Organized Fractality Through Etching of


  When a finite volume of etching solution is in contact with a disordered
solid, complex dynamics of the solid-solution interface develop. If the etchant
is consumed in the chemical reaction, the dynamics stop spontaneously on a
self-similar fractal surface. As only the weakest sites are corroded, the solid
surface gets progressively harder and harder. At the same time it becomes
rougher and rougher uncovering the critical spatial correlations typical of
percolation. From this, the chemical process reveals the latent percolation
criticality hidden in any random system. Recently, a simple minimal model has
been introduced by Sapoval et al. to describe this phenomenon. Through analytic
and numerical study, we obtain a detailed description of the process. The time
evolution of the solution corroding power and of the distribution of resistance
of surface sites is studied in detail. This study explains the progressive
hardening of the solid surface. Finally, this dynamical model appears to belong
to the universality class of Gra dient Percolation.

</DOC>
<DOC>
<DOCNO> 70134 </DOCNO>
Role of relativistic kinematics in describing two-quark systems


  An attempt to incorporate relativistic kinematics in the description of light
quark systems is made. It seems that the way of such incorporation along the
suggestion expressed by R. Gaida and his collaborators is very promising.
Comparison of these results with the experimental data concerning boson mass
spectrum shows that this approach is among the best theoretical interpretation
of the data.

</DOC>
<DOC>
<DOCNO> 10820 </DOCNO>
Strong Attraction between Charged Spheres due to Metastable Ionized


  We report a mechanism which can lead to long range attractions between
like-charged spherical macroions, stemming from the existence of metastable
ionized states. We show that the ground state of a single highly charged
colloid plus a few excess counterions is overcharged. For the case of two
highly charged macroions in their neutralizing divalent counterion solution we
demonstrate that, in the regime of strong Coulomb coupling, the counterion
clouds are very likely to be unevenly distributed, leading to one overcharged
and one undercharged macroion. This long-living metastable configuration in
turn leads to a long range Coulomb attraction.

</DOC>
<DOC>
<DOCNO> 170050 </DOCNO>
Concurrent Quantum Computation


  A quantum computer is a multi-particle interferometer that comprises beam
splitters at both ends and arms, where the n two-level particles undergo the
interactions among them. The arms are designed so that relevant functions
required to produce a computational result is stored in the phase shifts of the
2^n arms. They can be detected by interferometry that allows us to utilize
quantum parallelism. Quantum algorithms are accountable for what
interferometers to be constructed to compute particular problems. A standard
formalism for constructing the arms has been developed by the extension of
classical reversible gate arrays. By its nature of sequential applications of
logic operations, the required number of gates increases exponentially as the
problem size grows. This may cause a crucial obstacle to perform a quantum
computation within a limited decoherence time. We propose a direct and
concurrent construction of the interferometer arms by one-time evolution of a
physical system with arbitrary multi-particle interactions. It is inherently
quantum mechanical and has no classical analogue. Encoding the functions used
in Shor's algorithm for prime factoring, Grover's algorithm and Deutsch-Jozsa
algorithm requires only one-time evolution of such a system regardless of the
problem size n as opposed to its standard sequential counterpart that takes
O(n^3), O(n) and O(n2^n).

</DOC>
<DOC>
<DOCNO> 13534 </DOCNO>
Spin orthogonality catastrophe in two-dimensional antiferromagnets and


  We compute the spectral function of a spin S hole injected into a
two-dimensional antiferromagnet or superconductor in the vicinity of a magnetic
quantum critical point. We show that, near van Hove singularities, the problem
maps onto that of a static vacancy carrying excess spin S. The hole creation
operator is characterized by a new boundary anomalous dimension and a vanishing
quasiparticle residue at the critical point. We discuss possible relevance to
photoemission spectra of cuprate superconductors near the anti-nodal points.

</DOC>
<DOC>
<DOCNO> 120208 </DOCNO>
The Space Density of low redshift AGN


  We present a new determination of the optical luminosity function (OLF) of
active galactic nuclei (AGN) at low redshifts (z<0.15) based on Hubble Space
Telescope (HST) observations of X-ray-selected AGN. The HST observations have
allowed us to derive a true nuclear luminosity function for these AGN. The
resulting OLF illustrates a two-power-law form similar to that derived for QSOs
at higher redshifts. At bright magnitudes, M_B<-20, the OLF derived here
exhibits good agreement with that derived from the Hamburg/ESO QSO survey.
However, the single power law form for the OLF derived from the Hamburg/ESO
survey is strongly ruled out by our data at M_B>-20. Although the estimate of
the OLF is best-fit by a power law slope at M_B<-20.5 that is flatter than the
slope of the OLF derived at z>0.35, the binned estimate of the low redshift OLF
is still consistent with an extrapolation of the $z>0.35$ OLF based on pure
luminosity evolution.

</DOC>
<DOC>
<DOCNO> 123136 </DOCNO>
Feedback from Galaxy Formation: Production and Photodissociation of


  We use one-dimensional radiative transfer simulations to study the evolution
of H_2 gas-phase (H^- catalyzed) formation and photo-dissociation regions in
the primordial universe. We find a new positive feedback mechanism capable of
producing shells of H_2 in the intergalactic medium, which are optically thick
in some Lyman-Werner bands. While these shells exist, this feedback effect is
important in reducing the H_2 dissociating background flux and the size of
photo-dissociation spheres around each luminous object. The maximum background
opacity of the IGM in the H_2 Lyman-Werner bands is \tau_{H_2} ~ 1-2 for a
relic molecular fraction x_{H_2}=2 x 10^{-6}, about 6 times greater than found
by Haiman, Abel & Rees. Therefore, the relic molecular hydrogen can decrease
the photo-dissociation rate by about an order of magnitude. The problem is
relevant to the formation of small primordial galaxies with masses M_{DM} <
10^8 M_\odot, that rely on molecular hydrogen cooling to collapse.
Alternatively, the universe may have remained dark for several hundred million
years after the birth of the first stars, until galaxies with virial
temperature T_{vir} > 10^4 K formed.

</DOC>
<DOC>
<DOCNO> 68100 </DOCNO>
Can the Higgs be seen in rapidity gap events at the Tevatron or the LHC?


  Double diffractive Higgs production at $pp$ (or $\bar{p}p$) colliders
continues to attract attention as a potential signal in the search for the
boson. We present improved perturbative QCD estimates of the event rates for
both the exclusive and inclusive double diffractive Higgs processes, paying
particular attention to the survival probability of the rapidity gaps. We find
that the major uncertainty is in the prediction for the survival probability
associated with soft rescattering. We show that an analogous process, the
double diffractive production of a pair of jets with large values of $E_T$, has
an event rate which makes it accessible at the Tevatron. Observation of this
process can therefore be used as a luminosity monitor for two- gluon exchange
processes, such as the production of a Higgs boson with rapidity gaps on either
side.

</DOC>
<DOC>
<DOCNO> 39840 </DOCNO>
Nucleon Electromagnetic Form Factors


  A review of data on the nucleon electromagnetic form factors in the
space-like region is presented. Recent results from experiments using polarized
beams and polarized targets or nucleon recoil polarimeters have yielded a
significant improvement on the precision of the data obtained with the
traditional Rosenbluth separation. Future plans for extended measurements are
outlined.

</DOC>
<DOC>
<DOCNO> 119732 </DOCNO>
Spatial resolution bias in the mid-infrared Starburst/AGN classification


  We present the effects of limited spatial resolution to the observed
mid-infrared (MIR) spectrum of an active galactic nucleus (AGN) surrounded by a
disk with massive star forming regions. Using MIR observations of the face-on
nearby Seyfert 1 galaxy NGC 6814, we vary the observing aperture and examine
the evolution of the observed AGN/starburst fraction with our MIR diagnostic.
We show that the spatial resolution of ISOCAM is sufficient to disentangle AGN
from starburst features in nuclear regions of nearby galaxies (D<50Mpc).
However, with the exception of a few ultra-luminous galaxies, dilution effects
hide completely the AGN contribution in more distant galaxies.

</DOC>
<DOC>
<DOCNO> 123288 </DOCNO>
Semi analytic approach to understanding the distribution of neutral


  Following Bi & Davidsen (1997), we perform one dimensional semi analytic
simulations along the lines of sight to model the intergalactic medium (IGM).
Since this procedure is computationally efficient in probing the parameter
space -- and reasonably accurate -- we use it to recover the values of various
parameters related to the IGM (for a fixed background cosmology) by comparing
the model predictions with different observations. For the currently favoured
LCDM model (\Omega_m=0.4, \Omega_{\Lambda}=0.6 and h=0.65), we obtain, using
statistics obtained from the transmitted flux, constraints on (i) the
combination f=(\Omega_B h^2)^2/J_{-12}, where \Omega_B is the baryonic density
parameter and J_{-12} is the total photoionisation rate in units of 10^{-12}
s^{-1}, (ii) temperature T_0 corresponding to the mean density and (iii) the
slope \gamma of the effective equation of state of the IGM at a mean redshift z
\simeq 2.5. We find that 0.8 <(T_0/10^4 K)< 2.5 and 1.3<\gamma<2.3. while the
constraint obtained on f is 0.020^2<f<0.032^2. A reliable lower bound on
J_{-12} can be used to put a lower bound on \Omega_B h^2, which can be compared
with similar constraints obtained from Big Bang Nucleosynthesis (BBN) and CMBR
studies. We find that if J_{-12}>1.2, the lower bound on \Omega_B h^2 is in
violation of the BBN value.

</DOC>
<DOC>
<DOCNO> 68888 </DOCNO>
Lepton number violating interactions and their effects on neutrino


  Mixing between bosons that transform differently under the standard model
gauge group, but identically under its unbroken subgroup, can induce
interactions that violate the total lepton number. We discuss four-fermion
operators that mediate lepton number violating neutrino interactions both in a
model-independent framework and within supersymmetry (SUSY) without R-parity.
The effective couplings of such operators are constrained by: i) the upper
bounds on the relevant elementary couplings between the bosons and the
fermions, ii) by the limit on universality violation in pion decays, iii) by
the data on neutrinoless double beta decay and, iv) by loop-induced neutrino
masses. We find that the present bounds imply that lepton number violating
neutrino interactions are not relevant for the solar and atmospheric neutrino
problems. Within SUSY without R-parity also the LSND anomaly cannot be
explained by such interactions, but one cannot rule out an effect
model-independently. Possible consequences for future terrestrial neutrino
oscillation experiments and for neutrinos from a supernova are discussed.

</DOC>
<DOC>
<DOCNO> 9897 </DOCNO>
A New Class of Magnetoresistance Oscillations: Interaction of a


  We report on a new class of magnetoresistance oscillations observed in a
high-mobility two-dimensional electron gas (2DEG) in GaAs-Al$_x$Ga$_{1-x}$As
heterostructures. Appearing in a weak magnetic field ($B<$ 0.3 T) and only in a
narrow temperature range (2 K $<T<$ 9 K), these oscillations are periodic in
1/B with a frequency proportional to the electron Fermi wave vector, $k_F$. We
interpret the effect as a magnetophonon resonance of the 2DEG with leaky
interface-acoustic phonon modes carrying a wave vector $q=2k_F$. Calculations
show a few branches of such modes on the GaAs-Al$_x$Ga$_{1-x}$As interface, and
their velocities are in quantitative agreement with the data.

</DOC>
<DOC>
<DOCNO> 121170 </DOCNO>
Near-infrared imaging of the host galaxies of three radio-loud quasars


  We present high spatial resolution near-infrared H-band (1.65 microns)
images, taken with ISAAC on UT1 of ESO VLT, of three radio-loud quasars at z =
1.5, as a pilot study for imaging of a larger sample of radio-loud and
radio-quiet quasars in the redshift range 1 < z < 2. We are able to clearly
detect the host galaxy in two quasars (PKS 0000-177 and PKS 0348-120) and
marginally in the third (PKS 0402-362). The host galaxies appear compact
(average bulge scale-length R(e) = 4 kpc) and luminous (average M(H) =
-27.6+-0.1). They are 2.5 mag more luminous than the typical galaxy luminosity
(M*(H) = -25.0+-0.2), and are comparable to the hosts of low redshift
radio-loud quasars (M(H) = -26), taking into account passive stellar evolution.
Their luminosities are also similar to those of high redshift radio galaxies.
All three quasars have at least one close companion galaxy at a projected
distance < 50 kpc from the quasar, assuming they are at the same redshift.

</DOC>
<DOC>
<DOCNO> 71036 </DOCNO>
Hadronic Decays of Excited Heavy Mesons


  We studied the hadronic decays of excited states of heavy mesons (D, D_s, B
and B_s) to lighter states by emission of pi, eta or K. Wavefunctions and
energy levels of these excited states are determined using a Dirac equation for
the light quark in the potential generated by the heavy quark (including first
order corrections in the heavy quark expansion). Transition amplitudes are
computed in the context of the Heavy Chiral Quark Model.

</DOC>
<DOC>
<DOCNO> 9606 </DOCNO>
Coherence scale of the Kondo lattice


  It is shown that the large-N approach yields two energy scales for the Kondo
lattice model. The single-impurity Kondo temperature, $T_K$, signals the onset
of local singlet formation, while Fermi liquid coherence sets in only below a
lower scale, $T^{\star}$. At low conduction electron density $n_c$
("exhaustion" limit), the ratio $T^{\star}/T_K$ is much smaller than unity, and
is shown to depend only on $n_c$ and not on the Kondo coupling. The physical
meaning of these two scales is demonstrated by computing several quantities as
a function of $n_c$ and temperature.

</DOC>
<DOC>
<DOCNO> 150432 </DOCNO>
Phases of dual superconductivity and confinement in softly broken N=2


  We study the electric flux tubes that undertake color confinement in N=2
supersymmetric Yang-Mills theories softly broken down to N=1 by perturbing with
the first two Casimir operators. The relevant Abelian Higgs model is not the
standard one due to the presence of an off-diagonal coupling among different
magnetic U(1) factors. We perform a preliminary study of this model at a
qualitative level. BPS vortices are explicitely obtained for particular values
of the soft breaking parameters. Generically however, even in the ultrastrong
scaling limit, vortices are not critical but live in a "hybrid" type II phase.
Also, ratios among string tensions are seen to follow no simple pattern. We
examine the situation at the half Higgsed vacua and find evidence for solutions
with the behaviour of superconducting strings. In some cases they are solutions
to BPS equations.

</DOC>
<DOC>
<DOCNO> 122155 </DOCNO>
The Origin of The Stellar Initial Mass Function


  Observations and theories of the stellar initial mass function are reviewed.
The universality and large total mass range of the power law portion of the IMF
suggest a connection between stellar mass and cloud structure. The fractal
patterns and formation times of young clusters suggest a further connection to
turbulence. There is also a similarity between the characteristic mass at the
lower end of the power law and the minimum self-gravitating mass in a typical
star-forming cloud. All of this suggests that the power law part of the IMF
comes from star formation in self-gravitating cloud pieces that are formed by
compressible turbulence. Timing constraints involving cloud destruction and
competition for gas might limit the upper stellar mass to several hundred suns.
This upper limit has to be less than the mass of a clump that has a dynamical
time equal to several times the dynamical time of the characteristic mass. The
smallest stars and brown dwarfs may not come directly from cloud clumps, which
are not self-gravitating at this mass in the cloudy phase, but from collapsed
fragments or other pieces connected with the formation of more massive stars.

</DOC>
<DOC>
<DOCNO> 174600 </DOCNO>
Simultaneous Measurements of the $p+d\to (A=3) +\pi$ Reactions


  A stack of annular detectors made of high purity germanium was used to
measure simultaneously $pd\to {^3H} \pi^+$ and $pd\to {^3He} \pi^0$
differential cross sections at beam momenta of 750 MeV/c, 800 MeV/c, and 850
MeV/c over a large angular range. The extracted total cross sections for the
$pd\to {^3He} \pi^0$ reactions bridge a gap between near threshold data and
those in the resonance region. The ratio of the cross sections for the two
reaction channels taken at the same $\eta={p^{cm}_\pi}/m_\pi$ yields
$2.11\pm0.08$ indicating that a deviation from isospin symmetry is very small.

</DOC>
<DOC>
<DOCNO> 102510 </DOCNO>
A Rationality Condition for the Existence of Odd Perfect Numbers


  A rationality condition is derived for the existence of odd perfect numbers
involving the square root of a product, which consists of a sequence of
repunits, multiplied by twice the base of one of the repunits. This constraint
also provides an upper bound for density of odd integers which could satisfy
${{\sigma(N)}\over N}=2$, where $N$ belongs to a fixed interval with a lower
limit greater than $10^{300}$. Characteristics of prime divisors of repunits
are used to establish whether the product containing the repunits can be a
perfect square. It is shown that the arithmetic primitive divisors with
different prime bases can be equal only when the exponents are different, with
the exception of a set of cases derived from solutions of a solution prime
equation. The proof of this result requires the demonstration of the
non-existence of solutions of a more general prime equation, a problem which is
equivalent to Catalan's conjecture. Results concerning the exponents of prime
divisors of the repunits are obtained, and they are combined with the method of
induction to prove to prove a general theorem on the non-existence of prime
divisors satisfying the rationality condition.

</DOC>
<DOC>
<DOCNO> 71405 </DOCNO>
Decay constants of B and D mesons from improved relativistic lattice QCD


  We present a calculation of the B and D meson decay constants in lattice QCD
with two (Nf=2) flavours of light dynamical quarks, using an O(a)-improved
Wilson action for both light and heavy quarks and a renormalization-group
improved gauge action. Simulations are made at three values of lattice spacing
a=0.22, 0.16, 0.11 fm and four values of sea quark mass in the range m_PS/m_V
\~= 0.8-0.6. Our estimate for the continuum values of the decay constants are
fBd = 208(10)(11) MeV, fBs = 250(10)(13)(^{+8}_{-0}) MeV, fDd = 225(14)(14)
MeV, fDs = 267(13)(17)(^{+10}_{-0}) MeV for Nf=2 where the statistical and
systematic errors are separately listed, and the third error for fBs and fDs
show uncertainty of determination of strange quark mass. We also carry out a
set of quenched simulations using the same action to make a direct examination
of sea quark effects. Taking the ratio of results for Nf=2 and Nf=0, we obtain
fb^{Nf=2}/fb^{Nf=0} = 1.11(6), fbs^{Nf=2}/fbs^{Nf=0} = 1.14(5),
fd^{Nf=2}/\fd^{Nf=0} = 1.03(6), fds^{Nf=2}/\fds^{Nf=0} = 1.07(5). They show a
10-15% increase in the Nf=2 results over those of Nf=0 for the B meson decay
constants, while evidence for such a trend is statistically less clear for the
D meson decay constants.

</DOC>
<DOC>
<DOCNO> 72034 </DOCNO>
The s-sbar and K-Kbar nature of f_0(980) in D_s decays


  We examine the D_s -> f_0(980) pi amplitude through a constituent quark-meson
model, incorporating heavy quark and chiral symmetries, finding a good
agreement with the recent E791 data analysis of D_s -> 3pi via f_0(980). The
f_0(980) resonance is considered at the moment of production as an s sbar
state, later evolving to a superposition of mainly s sbar and K Kbar. The
analysis is also extended to the more frequent process D_s -> phi pi.

</DOC>
<DOC>
<DOCNO> 117979 </DOCNO>
A Lens Mapping Algorithm for Weak Lensing


  We develop an algorithm for the reconstruction of the two-dimensional mass
distribution of a gravitational lens from the observable distortion of
background galaxies. From the measured reduced shear, the lens mapping is
obtained, from which a mass distribution is derived. This is unlike other
methods where the convergence ("kappa") is directly obtained. We show that this
method works best for sub-critical lenses, but can be applied to a critical
lens away from the critical lines. For finite fields the usual mass-sheet
degeneracy is shown to exist in this method as well. We show that the algorithm
reproduces the mass distribution within acceptable limits when applied to
simulated noisy data.

</DOC>
<DOC>
<DOCNO> 83385 </DOCNO>
A Tableau Calculus for Pronoun Resolution


  We present a tableau calculus for reasoning in fragments of natural language.
We focus on the problem of pronoun resolution and the way in which it
complicates automated theorem proving for natural language processing. A method
for explicitly manipulating contextual information during deduction is
proposed, where pronouns are resolved against this context during deduction. As
a result, pronoun resolution and deduction can be interleaved in such a way
that pronouns are only resolved if this is licensed by a deduction rule; this
helps us to avoid the combinatorial complexity of total pronoun disambiguation.

</DOC>
<DOC>
<DOCNO> 69195 </DOCNO>
Exclusive-Inclusive Ratio of Semileptonic Lambda_b-Decays


  We present theoretical evidence that the exclusive/inclusive ratio of
semileptonic $\Lambda_b$-decays exceeds that of semileptonic B-decays where the
experimental exclusive/inclusive ratio amounts to about 66%. We start from the
observation that the spectator quark model provides a lower bound on the
leading order Isgur-Wise function of the $\Lambda_b \to \Lambda_c$ transition
in terms of the corresponding $B \to D,D^*$ mesonic Isgur-Wise function.
Using experimental data for the $B \to D,D^*$ mesonic Isgur-Wise functions
this bound is established. Applying a Bethe-Salpeter model including spectator
quark interactions and a QCD sum rule estimate of the $\Lambda_b \to \Lambda_c$
transition form factor which satisfy the spectator quark model bound we predict
the exclusive/inclusive ratio of semileptonic $\Lambda_b$ decay rates to lie in
a range between 0.81 and 0.92. We also provide an upper bound on the baryonic
Isgur-Wise function which is determined from the requirement that the exclusive
rate should not exceed the inclusive rate.

</DOC>
<DOC>
<DOCNO> 10413 </DOCNO>
Reply to the Comment of Chudnovski and Garanin on Phonon assisted


  We reply to the comment of Chudnovsky and Garanin on the tunneling rate in
Mn_{12}.

</DOC>
<DOC>
<DOCNO> 118348 </DOCNO>
New gamma Doradus Stars from the Hipparcos Mission and Geneva Photometry


  A search for new gamma Dor stars was undertaken using the Hipparcos periodic
variable star catalogue and the Geneva photometric database, leading to a list
of 40 new candidates. We started a monitoring of the candidates which suited
the observational window with the CORALIE spectrograph at the Swiss Euler
Telescope for establishing a robust list of new gamma Dor stars and studying
line profile variations. We here present our long-term program.

</DOC>
<DOC>
<DOCNO> 102902 </DOCNO>
Dirac Operator on Embedded Hypersurfaces


  New extrinsic lower bounds are given for the classical Dirac operator on the
boundary of a compact domain of a spin manifold. The main tool is to solve some
boundary problems for the Dirac operator of the domain under boundary
conditions of Atiyah-Patodi-Singer type. Spinorial techniques are used to give
simple proofs of classical results for compact embedded hypersurfaces.

</DOC>
<DOC>
<DOCNO> 11025 </DOCNO>
Relativistic Fluctuations and Anomalous Darwin Terms in Superconductors


  The anomalous Darwin term, one of the recently derived relativistic
corrections to the conventional theory of superconductivity, is analysed in
detail. A new derivation of this term, much simpler than that given originally,
is presented and used to interpret the term physically, in terms of
fluctuations of the relativistic wave packet describing the paired electrons.
Several puzzling features of the original derivation find a simple explanation
in terms of this reinterpretation. The question of observability of the
anomalous Darwin term, and its relation to the conventional Darwin term and to
earlier proposed superconducting Darwin terms are also discussed.

</DOC>
<DOC>
<DOCNO> 11183 </DOCNO>
Mean Field Fluid Behavior of the Gaussian Core Model


  We show that the Gaussian core model of particles interacting via a
penetrable repulsive Gaussian potential, first considered by Stillinger (J.
Chem. Phys. 65, 3968 (1976)), behaves like a weakly correlated ``mean field
fluid'' over a surprisingly wide density and temperature range. In the bulk the
structure of the fluid phase is accurately described by the random phase
approximation for the direct correlation function, and by the more
sophisticated HNC integral equation. The resulting pressure deviates very
little from a simple, mean-field like, quadratic form in the density, while the
low density virial expansion turns out to have an extremely small radius of
convergence. Density profiles near a hard wall are also very accurately
described by the corresponding mean-field free-energy functional. The binary
version of the model exhibits a spinodal instability against de-mixing at high
densities. Possible implications for semi-dilute polymer solutions are
discussed.

</DOC>
<DOC>
<DOCNO> 121294 </DOCNO>
The cosmic rate of supernovae and the range of stars ending as Type Ia


  The present cosmic rate of Type Ia supernovae (SNeIa) suggests that about 6%
of all stars in binary systems with primaries in the initial mass range $3-9\
M\sun$ end up as SNeIa. If that is confirmed, the unavoidable conclusion is
that SNeIa can only be explained by the single degenerate scenario. At most 1%
of stars in binary systems in the above range end up as CO + CO WD pairs, with
total mass equal to or larger than the Chandrasekhar mass. Given that the
number of mergers from pairs of CO + He WDs that reach the Chandrasekhar mass
is even lower, the conclusion strongly favors binaries containing just one CO
WD as the progenitors of SNeIa, since the SNeIa production efficiency (relative
to the instantaneous star formation rate) predicted for double degenerate (DD)
pairs lies more than $3\sigma$ below the observational data, and the DD
scenario can be rejected at more than 99% confidence level. Only if the SFR
measurements from $z\sim 0.1$ to $z\sim 0.5$ are being underestimated by a
factor of 6 while SNeIa rates are not, can we escape the above conclusion. We
evaluate the numbers and characteristics of double WD systems with different
chemical compositions (CO and He WDs) that should form and compare them with
the observations, in order to check our predictions. Our conclusions appear
robust after that test.

</DOC>
<DOC>
<DOCNO> 40394 </DOCNO>
Neutrino suppression and extra dimensions: a minimal model


  We study flavour neutrinos confined to our 4-dimensional world coupled to one
"bulk" state, i.e. a Kaluza-Klein tower. We discuss the spatial development of
the neutrino disappearance, the possibility of resurgence and the effective
flavour transitions induced in this mechanism. We show that even a simple model
can produce an energy-independent suppression at large distances, and relate
this to experimental data.

</DOC>
<DOC>
<DOCNO> 10676 </DOCNO>
Topological Character of Excitations in Strongly Correlated Electronic


  Topologically nontrivial states are common in symmetry broken phases at
macroscopic scales. Low dimensional systems bring them to a microscopic level
where solitons emerge as single particles. The earliest and latest applications
are conducting polymers and spin-Peierls chains. After a history introduction,
we shall discuss the topological aspects of elementary excitations, especially
the confinement and the dimensional D crossover. At the 1D level we exploit
results of different exact and approximate techniques in theory of solitons,
for both quantum and semiclassical models, and the related knowledge on
anomalous charges and currents. At higher D the topological requirements for
the combined symmetry originate the spin- or charge- roton like excitations
with charge- or spin- kinks localized in the core. In quasi 1D world they can
be viewed as resulting from a spin-charge recombination due to the 3D
confinement.

</DOC>
<DOC>
<DOCNO> 151838 </DOCNO>
On the gravitational waves on the background of anomaly-induced


  In the very early Universe matter can be described as a conformal invariant
ultra-relativistic perfect fluid, which does not contribute, on classical
level, to the evolution of the isotropic and homogeneous metric. However, in
this situation the vacuum effects of quantum matter fields become important.
The vacuum effective action depends, essentially, on the particle content of
the underlying gauge model. If we suppose that there is some desert in the
particle spectrum, just below the Planck mass, then the effect of conformal
trace anomaly is dominating at the corresponding energies. With some additional
constraints on the gauge model (which favor extended or supersymmetric versions
of the Standard Model rather than the minimal one), one arrives at the stable
inflation. In this article we report about the calculation of the gravitational
waves in this model. The result for the perturbation spectrum is close to the
one for the conventional inflaton model, and is in agreement with the existing
Cobe data.

</DOC>
<DOC>
<DOCNO> 123249 </DOCNO>
The Peculiar Motions of Early-Type Galaxies in Two Distant Regions VI:


  The EFAR project is designed to measure the properties and peculiar motions
of early-type galaxies in two distant regions. Here we describe the maximum
likelihood algorithm we developed to investigate the correlations between the
parameters of the EFAR database. One-, two-, and three-dimensional gaussian
models are constructed to determine the mean value and intrinsic spread of the
parameters, and the slopes and intrinsic parallel and orthogonal spread of the
Mgb'-Mg2, Mg2-sigma, Mgb'-sigma relations, and the Fundamental Plane. In the
latter case, the cluster peculiar velocities are also determined. We show that
this method is superior to ``canonical'' approaches of least-squares type,
which give biased slopes and biased peculiar velocities. We test the algorithm
with Monte Carlo simulations of mock EFAR catalogues and derive the systematic
and random errors on the estimated parameters. We find that random errors are
always dominant. We estimate the influence of systematic errors due to the way
clusters were selected and the hard limits and uncertainties in the selection
function parameters for the galaxies. We explore the influence of uniform
distributions in the Fundamental Plane parameters and the errors. We conclude
that the mean peculiar motions of the EFAR clusters can be determined reliably.
In particular, the placement of the two EFAR sample regions relative to the
Lauer and Postman dipole allows us to strongly constrain the amplitude of the
bulk motion in this direction.

</DOC>
<DOC>
<DOCNO> 85156 </DOCNO>
High quality factor measured in fused silica


  We have measured the mechanical dissipation in a sample of fused silica drawn
into a rod. The sample was hung from a multiple-bob suspension, which isolated
it from rubbing against its support, from recoil in the support structure, and
from seismic noise. The quality factor, Q, was measured for several modes with
a high value of 57 million found for mode number 2 at 726 Hz. This result is
about a factor 2 higher than previous room temperature measurements. The
measured Q was strongly dependent on handling, with a pristine flame-polished
surface yielding a Q 3-4 times higher than a surface which had been knocked
several times against a copper tube.

</DOC>
<DOC>
<DOCNO> 120126 </DOCNO>
Low Redshift QSO Lyman alpha Absorption Line Systems Associated with


  In this paper we present Monte-Carlo simulations of Lyman alpha absorption
systems which originate in galactic haloes, galaxy discs and dark matter (DM)
satellites around big central haloes. It is found that for strong Lyman alpha
absorption lines galactic haloes and satellites can explain ~20% and 40% of the
line number density of QSO absorption line key project respectively. If big
galaxies indeed possess such large numbers of DM satellites and they possess
gas, these satellites may play an important role for strong Lyman alpha lines.
However the predicted number density of Lyman-limit systems by satellites is
\~0.1 (per unit redshift), which is four times smaller than that by halo
clouds. Including galactic haloes, satellites and HI discs of spirals, the
predicted number density of strong lines can be as much as 60% of the HST
result. The models can also predict all of the observed Lyman-limit systems.
The average covering factor within 250 kpc/h is estimated to be ~0.36. And the
effective absorption radius of a galaxy is estimated to be ~150 kpc/h. The
models predict W_r propto rho^{-0.5} L_B^{0.15} (1+z)^{-0.5}. We study the
selection effects of selection criteria similar to the imaging and
spectroscopic surveys. We simulate mock observations through known QSO
lines-of-sight and find that selection effects can statistically tighten the
dependence of line width on projected distance. (abridged)

</DOC>
<DOC>
<DOCNO> 118987 </DOCNO>
Density dependent strong coupling constant of QCD derived from compact


  The present work is an endeavour to connect the properties of tiny nearly
massless objects with those of some of the most massive ones, the compact
stars.
  Since 1996 there is major influx of X-ray and $\gamma$ ray data from binary
stars, one or both of which are compact objects that are difficult to explain
as neutron stars since they contain a mass M in too small a radius R . The
suggestion has been put forward that these are strange quark stars (SS)
explainable in a simple model with chiral symmetry restoration (CSR) for the
quarks and the M, R and other properties like QPOs (quasi periodic
oscillations) in their X-ray power spectrum.
  It would be nice if this astrophysical data could shed some light on
fundamental properties of quarks obeying QCD. One can relate the strong
coupling constant of QCD, $\alpha_s$ to the quark mass through the
Dyson-Schwinger gap equation using the real time formalism of Dolan and Jackiw.
This enables us to obtain the density dependence of $\alpha_s$ from the simple
CSR referred to above. This way fundamental physics, difficult to extract from
other models like for example lattice QCD, can be constrained from present-day
compact star data and may be put back to modelling the dense quark phase of
early universe.

</DOC>
<DOC>
<DOCNO> 9132 </DOCNO>
Three-point density correlation functions in the fractional quantum Hall


  In this paper we consider the three-particle density correlation function for
a fractional quantum Hall liquid. The study of this object is motivated by
recent experimental studies of fractional quantum Hall systems using inelastic
light scattering and phonon absorption techniques. Symmetry properties of the
correlation function are noted. An exact sum-rule is derived which this
quantity must obey. This sum-rule is used to assess the convolution
approximation that has been used to estimate the matrix elements for such
experiments. PACS Numbers: 73.40.Hm, 73.20.Mf, 72.10.Di

</DOC>
<DOC>
<DOCNO> 119260 </DOCNO>
Probing the gas content of the dwarf galaxy NGC 3109 with background


  We established the catalog of X-ray point sources in the field of the
Magellanic-type spiral galaxy NGC 3109 (DDO 236) from two ROSAT PSPC
observations. Of the 91 X-ray sources 26 are contained within the HI extent of
NGC 3109 as derived by Jobin & Carignan (1990) with the VLA. For 10 of these we
can determine accurate hardness ratios delta HR2<=0.2. We find 3 candidate AGN,
2 candidate X-ray binaries and one source which may belong to either class. We
also find 2 candidate foreground stars. In a field of 8'x8' observed with the
NTT in the I-band and centered on the nucleus of NGC 3109 we determine
candidate optical counterparts in the X-ray error circle of 7 ROSAT PSPC
sources. We apply a spectral fit to the ROSAT spectrum of the X-ray brightest
absorbed candidate AGN behind NGC 3109, RX J1003.2-2607. Assuming a galactic
foreground hydrogen column density of 4.3 10^20 cm^-2 we derive from the X-ray
spectral fit, assuming reduced metallicities (~0.2 solar), a hydrogen column
density due to NGC 3109 of 11(+7,-5) 10^20 cm^-2. This value is slightly larger
than the hydrogen column density derived from the 21-cm observations of ~8
10^20 cm^-2. We estimate that the molecular mass fraction of the gas is not
larger than ~60%.

</DOC>
<DOC>
<DOCNO> 119853 </DOCNO>
Collimated outflows of rapidly rotating young stellar objects


  We present an analytical model for the magnetic flux surfaces for rapidly
rotating magnetized young stellar objects which is based on ideal, stationary,
axisymmetric magnetohydrodynamics. The resulting cold wind solutions reproduce
observed wind velocities of a few hundred \kms$ $ and the outer jet radi us for
a collimated jet of several thousand stellar radii. The theory of axisymmetric
magnetospheres around rapidly rotating stellar sources is outlined including
electric fields due to the rapid rotation. Gravity of the central object is
consistently built into this theory. A consistent wind theory is developed
which contains the Newtonian theory as a classical limit. Current--carrying
plasma flows will lead to a collimation of the magnetospheric structure into a
cylindrical shape. We show that the asymptotic structure is essentially
determined by electric forces in the pinch equation, and not by centrifugal and
pressure forces.

</DOC>
<DOC>
<DOCNO> 122347 </DOCNO>
The X-ray outbursts of Be/X-ray transients


  We present a new scenario for the behaviour of Be/X-ray binaries based on
long-term multiwavelength monitoring and the decretion disc model. The
circumstellar discs of the primaries are truncated because of the tidal and
resonant effect of the neutron star. The geometry of the systems and the value
of viscosity determine the presence or absence of Type I X-ray outbursts. The
interaction of a strongly disturbed disc with the neutron star originates Type
II X-ray and optical outbursts.

</DOC>
<DOC>
<DOCNO> 117003 </DOCNO>
An Overview of the Spallation Neutron Source Project


  The Spallation Neutron Source (SNS) is being designed, constructed, installed
and commissioned by the staff of six national laboratories, Argonne National
Laboratory, Brookhaven National Laboratory, Jefferson National Accelerator
Laboratory, Lawrence Berkeley National Laboratory, Los Alamos National
Laboratory, and Oak Ridge National Laboratory. The accelerator systems are
designed to deliver a 695 ns proton-pulse onto a mercury target at a 60-Hz
repetition rate and an average power of 2-MW. Neutron moderators that will
convert the spallation neutrons into slow neutrons for material science
research will surround the target. The Front-End systems are designed to
generate an H- beam of minipulses, 68% beam on, 32% beam off every 965 ns, at
2.5 MeV for 1 ms, 60 times a second. The Front-End systems include a RF driven,
volume-production ion source, beam chopping system, RFQ, and beam transport.
The ion source will have to achieve about 65 mA to deliver 52 mA at the input
to the linac. The linac consists of a drift tube linac up to 86.8 MeV, a
coupled-cell linac to 185 MeV, and a superconducting RF linac to the nominal
energy of 1 GeV. The design of the superconducting section includes 11
cryomodules with three, 0.61-beta cavities per cryomodule and 17 cryomodules
with four, 0.81-beta cavities per cryomodule, with space to install four more
0.81-beta cryomodules. The accumulator ring is designed for charge exchange
injection at full energy. The peak charge per bunch at the end of the
accumulation cycle will reach 2.08x10**14 for 2-MW operation. The goal is to
control beam losses to less than 1x10**-4.

</DOC>
<DOC>
<DOCNO> 68819 </DOCNO>
Some Dynamical Effects of the Cosmological Constant


  Newton's law gets modified in the presence of a cosmological constant by a
small repulsive term (antigarvity) that is proportional to the distance.
Assuming a value of the cosmological constant consistent with the recent SnIa
data ($\Lambda \simeq 10^{-52} m^{-2}$) we investigate the significance of this
term on various astrophysical scales. We find that on galactic scales or
smaller (less than a few tens of kpc) the dynamical effects of the vacuum
energy are negligible by several orders of magnitude. On scales of 1Mpc or
larger however we find that vacuum energy can significantly affect the
dynamics. For example we show that the velocity data in the Local Group of
galaxies correspond to galactic masses increased by 35% in the presence of
vacuum energy. The effect is even more important on larger low density systems
like clusters of galaxies or superclusters.

</DOC>
<DOC>
<DOCNO> 67833 </DOCNO>
Delta I = 1/2 enhancement and the Glashow-Schnitzer-Weinberg sum rule


  In 1967 Glashow, Schnitzer and Weinberg derived a sum rule in the soft-pion
and soft kaon limit relating the Delta I=1/2 non-leptonic K->2pi amplitude to
integrals over strange and non-strange spectral functions. Using the recent
ALEPH data from tau-decay, we show that the sum rule, slightly modified to
reduce contributions near the cut, yields the correct magnitude decay amplitude
corresponding to the Delta I=1/2 rule.

</DOC>
<DOC>
<DOCNO> 151349 </DOCNO>
AdS Box Graphs, Unitarity and Operator Product Expansions


  We develop a method of singularity analysis for conformal graphs which, in
particular, is applicable to the holographic image of AdS supergravity theory.
It can be used to determine the critical exponents for any such graph in a
given channel. These exponents determine the towers of conformal blocks that
are exchanged in this channel. We analyze the scalar AdS box graph and show
that it has the same critical exponents as the corresponding CFT box graph.
Thus pairs of external fields couple to the same exchanged conformal blocks in
both theories. This is looked upon as a general structural argument supporting
the Maldacena hypothesis.

</DOC>
<DOC>
<DOCNO> 150345 </DOCNO>
On Open/Closed String Duality


  It was recently shown, using the AdS/CFT correspondence, that the low energy
effective action of a large $N$ open string theory satisfies a holographic RG
flow equation closely related to the Hamilton-Jacobi equation of 5-d
supergravity. In this paper we re-obtain the same flow equation in the dual
regime of small 't Hooft coupling $\lambda\ll 1$. Our derivation makes use of
the conformal equivalence between planar open string diagrams and closed string
tree diagrams. This equivalence can be viewed as a microscopic explanation of
the open/closed string duality that underlies the AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 178916 </DOCNO>
Asymptotic Behavior of Nucleon Electromagnetic Form Factors in Space-


  We compare the existing data about electromagnetic form factors of the proton
in the time-like region of momentum transfer (up to $q^2\simeq$ 14
(GeV/c)$^2$), with the corresponding data in the space-like region. From the
constrains given by the Phragm\`en-Lindel\"of theorem, it turns out that the
asymptotic regime can not be reached simultaneously for both form factors
(electric and magnetic) in the considered region of momentum transfer. The
angular dependence for the annihilation processes, such as
$\bar{p}+p\leftrightarrow e^++e^-$, is sensitive to the asymptotic properties
of form factors and to the two-photon physics in the time-like region.

</DOC>
<DOC>
<DOCNO> 70232 </DOCNO>
Single Top Production as a Window to Physics Beyond the Standard Model


  Production of single top quarks at a high energy hadron collider is studied
as a means to identify physics beyond the standard model related to the
electroweak symmetry breaking. The sensitivity of the $s$-channel $W^*$ mode,
the $t$-channel $W$-gluon fusion mode, and the \tw mode to various possible
forms of new physics is assessed, and it is found that the three modes are
sensitive to different forms of new physics, indicating that they provide
complimentary information about the properties of the top quark. Polarization
observables are also considered, and found to provide potentially useful
information about the structure of the interactions of top.

</DOC>
<DOC>
<DOCNO> 9746 </DOCNO>
Landau Level Mixing and Skyrmion Stability in Quantum Hall Ferromagnets


  We present a Hartree-Fock study that incorporates the effects of Landau level
mixing and screening due to filled levels into the computation of energies and
states of quasiparticles in quantum Hall ferromagnets.
  We use it to construct a phase diagram for skyrmion stability as a function
of magnetic field and Zeeman coupling strengths. We find that Landau level
mixing tends to favor spin-polarized quasiparticles, while finite thickness
corrections favor skyrmions. Our studies show that skyrmion stability in high
Landau levels is very sensitive to the way in which electron-electron
interactions are modified by finite thickness, and indicate that it is crucial
to use models with realistic short distance behavior to get qualitatively
correct results.
  We find that recent experimental evidence for skyrmions in higher Landau
levels cannot be explained within our model.

</DOC>
<DOC>
<DOCNO> 8991 </DOCNO>
Dynamic Scaling for First-order Phase Transtions


  The critical behaviour in short time dynamics for the q=6 and 7 state Potts
models in two-dimensions is investigated. It is shown that dynamic finite-size
scaling exists for first-order phase transitions.

</DOC>
<DOC>
<DOCNO> 118399 </DOCNO>
On the tilting of protostellar disks by resonant tidal effects


  We consider the dynamics of a protostellar disk surrounding a star in a
circular-orbit binary system. Our aim is to determine whether, if the disk is
initially tilted with respect to the plane of the binary orbit, the inclination
of the system will increase or decrease with time. The problem is formulated in
the binary frame in which the tidal potential of the companion star is static.
We consider a steady, flat disk that is aligned with the binary plane and
investigate its linear stability with respect to tilting or warping
perturbations. The dynamics is controlled by the competing effects of the m=0
and m=2 azimuthal Fourier components of the tidal potential. In the presence of
dissipation, the m=0 component causes alignment of the system, while the m=2
component has the opposite tendency. We find that disks that are sufficiently
large, in particular those that extend to their tidal truncation radii, are
generally stable and will therefore tend to alignment with the binary plane on
a time-scale comparable to that found in previous studies. However, the effect
of the m=2 component is enhanced in the vicinity of resonances where the outer
radius of the disk is such that the natural frequency of a global bending mode
of the disk is equal to twice the binary orbital frequency. Under such
circumstances, the disk can be unstable to tilting and acquire a warped shape,
even in the absence of dissipation. The outer radius corresponding to the
primary resonance is always smaller than the tidal truncation radius. For disks
smaller than the primary resonance, the m=2 component may be able to cause a
very slow growth of inclination through the effect of a near resonance that
occurs close to the disk center. We discuss these results in the light of
recent observations of protostellar disks in binary systems.

</DOC>
<DOC>
<DOCNO> 69204 </DOCNO>
Pair production of doubly heavy baryons


  We analytically calculate the total and differential cross sections for the
pair production of doubly heavy baryons in the framework of diquark model. The
processes of electron-positron and quark-antiquark annihilations are
considered. The fractions of doubly heavy baryons in the yields of heavy quarks
are evaluated numerically.

</DOC>
<DOC>
<DOCNO> 12997 </DOCNO>
Three-dimensional micro-electromagnet traps for neutral and charged


  Three-dimensional (3D) micro-electromagnets were developed to control
particle motion in magnetic field landscapes in vacuum near a chip. Multiple
layers of micron-scale conductors separated by transparent insulators create
particle containers with deep, symmetric and time-dependent potentials,
suitable for integration in quantum circuits. Single and coupled multiple 3D
traps, integrated 3D traps with a mirror, 3D guides for neutral particles with
spin, and traps for electrons in vacuum are described.

</DOC>
<DOC>
<DOCNO> 67674 </DOCNO>
Hadron spectroscopy based on relativistic Schr\"odinger-like wave


  Relativistic potential-type equations are proposed which approximately
reproduce important features and constraints of field-theoretic models and can
be useful tool in hadron spectroscopy. Within this approach, the
Regge-trajectory parameters and some properties of hihger radial excitations in
the light quark sector are discussed.

</DOC>
<DOC>
<DOCNO> 102071 </DOCNO>
The Symplectic Sum Formula for Gromov-Witten Invariants


  In the symplectic category there is a `connect sum' operation that glues
symplectic manifolds by identifying neighborhoods of embedded codimension two
submanifolds. This paper establishes a formula for the Gromov-Witten invariants
of a symplectic sum Z=X#Y in terms of the relative GW invariants of X and Y.
Several applications to enumerative geometry are given.

</DOC>
<DOC>
<DOCNO> 170432 </DOCNO>
How big is a quantum computer?


  Accounting for resources is the central issue in computational efficiency. We
point out physical constraints implicit in information readout that have been
overlooked in classical computing. The basic particle-counting mode of read-out
sets a lower bound on the resources needed to implement a quantum computer. As
a consequence, computers based on classical waves are as efficient as those
based on single quantum particles.

</DOC>
<DOC>
<DOCNO> 120902 </DOCNO>
Magnetized accretion-ejection structures V. Effects of entropy


  In this paper, steady-state MHD calculations of non-relativistic magnetized
accretion discs driving jets are presented. For the first time, an energy
equation describing the effects of entropy generation along streamlines is
included. Using a simplified approach, we showed that thermal effects have a
tremendous influence on the disc capability to feed jets with mass.
  The disc ejection efficiency is measured by the parameter $\xi= d \ln
\dot{M}_{a}/d \ln{r}$, where $ \dot{M}_{a}(r)$ is the local disc accretion
rate. While previous self-similar solutions were only able to produce jets with
$\xi \sim 0.01$, solutions with a coronal heating display huge efficiencies up
to $\xi \sim 0.5$. Moreover, taking thermal effects into account allows to
obtain both fast and slow magnetic rotators.
  Since most of the jet properties (like asymptotic velocity or degree of
collimation) depend on the mass load, it arises from this study that any
quantitative result requires a detailled analysis of the disc energetics.

</DOC>
<DOC>
<DOCNO> 71140 </DOCNO>
A Variational Fock-Space Treatment of Quarkonium


  The variational method and the Hamiltonian formalism of QCD are used to
derive relativistic, momentum space integral equations for a quark-antiquark
system with an arbitrary number of gluons present. As a first step, the
resulting infinite chain of coupled equations is solved in the nonrelativistic
limit by an approximate decoupling method. Comparison with experiment allows us
to fix the quark mass and coupling constant, allowing for the calculation of
the spectra of massive systems such as charmonium and bottomonium. Studying the
results with and without the nonAbelian terms, we find that the presence of the
nonAbelian factors yields better agreement with the experimental spectra.

</DOC>
<DOC>
<DOCNO> 11125 </DOCNO>
Algebraic Study of Quantum Many-Body Systems With Nearest And


  The bound and scattering states of the many-body systems, related to the
short-range Dyson model, are studied. The Hamiltonian for the full-line problem
is mapped to decoupled oscillators; using this connection we establish an
equivalent of the Stanley-Macdonald conjecture in the present case. Further, we
show that the scattering states can be realized as coherent states. As in the
Calogero case, the scattering scenario in our case yields that the initial
momenta, $\{k_i\}$, go over to the final momenta, $\{k_i^\prime = k_{N+1-i}\}$,
with energy independent phase shift. We also establish the unitary equivalence
of the scattering Hamiltonian to free particles. Finally, we analyse both the
$A_{N-1}$ and $BC_N$ models on circle and construct a number of eigenfunctions
by making use of symmetry arguments.

</DOC>
<DOC>
<DOCNO> 68903 </DOCNO>
The "recoil" correction of order $m \alpha^6$ to hyperfine splitting of


  The "recoil" correction of order $m \alpha^6$ to the hyperfine splitting of
positronium ground state was found. The formalism employed is based on the
noncovariant perturbation theory in QED. Equation for two-particle component of
full (many-body) wave function is used, in which effective Hamiltonian depends
on the energy of a system. The effective Hamiltonian is not restricted to the
nonrelativistic region, so there is no need in any regularization. To evaluate
integrals over loop momenta, they are divided into "hard" and "soft" parts,
coming from large and small momenta respectively. Soft contributions were found
analytically, and hard ones are evaluated by numerical integration. Some soft
terms due to the retardation cancel each other. To calculate the "hard"
contributions, a great number of noncovariant graphs is replaced by only a few
covariant ones. The hard contribution was found in two ways. The first way is
to evaluate contributions of separate graphs, using the Coulomb gauge. The
second one is to calculate full hard contribution as a whole using the Feynman
gauge. The final result for the "recoil" correction is $0.381(6) m\al^6$ and
agrees with those of previous papers. Diagram-to-diagram comparison with the
revised results of Adkins&Sapirstein was done. All the results agree, so the
"recoil" correction is now firmly established. This means a considerable
disagreement with the experimental data.

</DOC>
<DOC>
<DOCNO> 151394 </DOCNO>
D-branes on Stringy Calabi-Yau Manifolds


  We argue that D-branes corresponding to rational B boundary states in a
Gepner model can be understood as fractional branes in the Landau-Ginzburg
orbifold phase of the linear sigma model description. Combining this idea with
the generalized McKay correspondence allows us to identify these states with
coherent sheaves, and to calculate their K-theory classes in the large volume
limit, without needing to invoke mirror symmetry. We check this identification
against the mirror symmetry results for the example of the Calabi-Yau
hypersurface in $\WP^{1,1,2,2,2}$.

</DOC>
<DOC>
<DOCNO> 150729 </DOCNO>
Searching for S-duality in Gravitation


  We overview some attempts to find S-duality analogues of non-supersymmetric
Yang-Mills theory, in the context of gravity theories. The case of
MacDowell-Mansouri gauge theory of gravity is discussed. Three-dimensional
dimensional reductions from the topological gravitational sector in four
dimensions, enable to recuperate the 2+1 Chern-Simons gravity and the
corresponding S-dual theory, from the notion of self-duality in the
four-dimensional theory.

</DOC>
<DOC>
<DOCNO> 40143 </DOCNO>
Searching for a stop-pair sample from top counting experiments at hadron


  The light stop pair if produced in hadron colliders and decaying through the
likely decay chain stop->chargino + b followed by chargino->neutralino + f f',
can mimic closely a top quark event when the mass of the stop is close to that
of the top quark. Because of the much lower production rate, the stop event can
be buried under the top quark event sample. In order to uncover the stop event,
specific selection cuts need to be applied. Through Monte Carlo simulation with
suitable kinematic cuts, we found that such stop event can be extracted from
the top quark sample and detected by the top quark counting experiments in the
upcoming upgraded Tevatron and LHC. However, because of the small statistics of
the Run 1 of the Tevatron, the stop signal remains hidden at Run 1.

</DOC>
<DOC>
<DOCNO> 101147 </DOCNO>
A splitting theorem for Kahler manifolds whose Ricci tensors have


  It is proved that a compact Kahler manifold whose Ricci tensor has two
distinct, constant, non-negative eigenvalues is locally the product of two
Kahler-Einstein manifolds. A stronger result is established for the case of
Kahler surfaces. Irreducible Kahler manifolds with two distinct, constant
eigenvalues of the Ricci tensor are shown to exist in various situations: there
are homogeneous examples of any complex dimension n > 1, if one eigenvalue is
negative and the other positive or zero, and of any complex dimension n > 2, if
the both eigenvalues are negative; there are non-homogeneous examples of
complex dimension 2, if one of the eigenvalues is zero. The problem of
existence of Kahler metrics whose Ricci tensor has two distinct, constant
eigenvalues is related to the celebrated (still open) Goldberg conjecture.
Consequently, the irreducible homogeneous examples with negative eigenvalues
give rise to complete, Einstein, strictly almost Kahler metrics of any even
real dimension greater than 4.

</DOC>
<DOC>
<DOCNO> 152597 </DOCNO>
M-Fivebranes Wrapped on Supersymmetric Cycles


  We construct supergravity solutions dual to the twisted field theories
arising when M-theory fivebranes wrap general supersymmetric cycles. The
solutions are constructed in maximal D=7 gauged supergravity and then uplifted
to D=11. Our analysis covers Kahler, special Lagrangian and exceptional
calibrated cycles. The metric on the cycles are Einstein, but do not
necessarily have constant curvature. We find many new examples of AdS/CFT
duality, corresponding to the IR superconformal fixed points of the twisted
field theories.

</DOC>
<DOC>
<DOCNO> 68352 </DOCNO>
Virtual Color Superconductivity--Status and Perspective


  The status of our understanding of the properties and manifestations of color
superconductivity at zero and low density is briefly reviewed. Future
possibility is highlighted.

</DOC>
<DOC>
<DOCNO> 84991 </DOCNO>
Initial Data for Numerical Relativity


  Initial data are the starting point for any numerical simulation. In the case
of numerical relativity, Einstein's equations constrain our choices of these
initial data. We will examine several of the formalisms used for specifying
Cauchy initial data in the 3+1 decomposition of Einstein's equations. We will
then explore how these formalisms have been used in constructing initial data
for spacetimes containing black holes and neutron stars. In the topics
discussed, emphasis is placed on those issues that are important for obtaining
astrophysically realistic initial data for compact binary coalescence.

</DOC>
<DOC>
<DOCNO> 121601 </DOCNO>
The Formation of Broad Line Clouds in the Accretion Shocks of Active


  Recent work on the gas dynamics in the Galactic Center has improved our
understanding of the accretion processes in galactic nuclei, particularly with
regard to properties such as the specific angular momentum distribution,
density, and temperature of the inflowing plasma. This information can be
valuable in trying to determine the origin of the Broad Line Region (BLR) in
Active Galactic Nuclei (AGNs). In this paper, we explore various scenarios for
the cloud formation based on the underlying principle that the source of plasma
is ultimately that portion of the gas trapped by the central black hole from
the interstellar medium. Based on what we know about the Galactic Center, it is
likely that in highly dynamic environments such as this, the supply of matter
is due mostly to stellar winds from the central cluster. Winds accreting onto a
central black hole are subjected to several disturbances capable of producing
shocks, including a Bondi-Hoyle flow, stellar wind-wind collisions, and
turbulence. Shocked gas is initially compressed and heated out of thermal
equilibrium with the ambient radiation field; a cooling instability sets in as
the gas is cooled via inverse-Compton and bremsstrahlung processes. If the
cooling time is less than the dynamical flow time through the shock region, the
gas may clump to form the clouds responsible for broad line emission seen in
many AGN spectra. Clouds produced by this process display the correct range of
densities and velocity fields seen in broad emission lines. Very importantly,
the cloud distribution agrees with the results of reverberation studies, in
which it is seen that the central line peak responds slower to continuum
changes than the line wings.

</DOC>
<DOC>
<DOCNO> 102025 </DOCNO>
Construction of All WZW Orbifold Actions


  In terms of group orbifold elements with definite monodromy, we give a
construction for the action functionals of the twisted sectors of all WZW
orbifolds. Surprisingly, locality of the theory dictates a form of the general
twisted current algebra in which the twisted right and left mover current
algebras are not a priori copies of each other. For the permutation orbifolds
and the inner-automorphic orbifolds we are able to show by a mode relabelling
that the situation is equivalent to copies, but we do not have an argument that
this is always the case. In an extension, we also construct the actions for all
the orbifolds of any nonlinear sigma model with a symmetry which acts linearly
on the coordinates. Finally, implications for orbifold conformal field theory
are discussed, including a conjectured set of orbifold Einstein equations for
those sigma model orbifolds in this class which are also 1-loop conformal.

</DOC>
<DOC>
<DOCNO> 120065 </DOCNO>
Solar flare radio pulsations as a signature of dynamic magnetic


  Decimetric radio observations of the impulsive solar flare on October 5,
1992, 09:25 UT show a long series of quasi-periodic pulsations deeply
modulating a continuum in the 0.6-2 GHz range that is slowly drifting toward
lower frequencies. We propose a model in which the pulsations of the radio flux
are caused by quasi-periodic particle acceleration episodes that result from a
dynamic phase of magnetic reconnection in a large-scale current sheet. The
reconnection is dominated by repeated formation and subsequent coalescence of
magnetic islands (known as ``secondary tearing'' or ``impulsive bursty'' regime
of reconnection), while a continuously growing plasmoid is fed by newly
coalescing islands. Such a model, involving a current sheet and a growing
plasmoid, is consistent with the Yohkoh observations of the same flare (Ohyama
& Shibata 1998). We present two-dimensional MHD simulations of dynamic magnetic
reconnection that support the model. Within the framework of the proposed
interpretation, the radio observations reveal details of plasmoid formation in
flares.

</DOC>
<DOC>
<DOCNO> 10939 </DOCNO>
Spin magnetic susceptibility in the two-layer Hubbard model


  The two-layer Hubbard model is studied by using the composite operator
method. Magnetic properties of the model in the normal state are analyzed by
studying the uniform static spin magnetic susceptibility as a function of
doping and temperature. The relevance of the model to describe the physical
behavior of two-layered cuprate high-$T_{c}$ superconductors is discussed.

</DOC>
<DOC>
<DOCNO> 117739 </DOCNO>
Comptonization of the Cosmic Microwave Background by Relativistic Plasma


  (Abridged) We investigate the spectral distortion of the cosmic microwave
background (CMB) caused by relativistic plasma. Within the Thomson regime, an
exact analytic expression for the photon scattering kernel of a momentum
power-law electron distribution is given. The ultra-relativistic
Sunyaev-Zeldovich (SZ) decrement measures the electron number and not the
energy content. On the other hand, the relativistic SZ increment at higher
frequencies depends strongly on the spectral shape of the electrons. We
calculate the expected Comptonization due to the energy release of radio
galaxies, which we estimate to be 3 10^66 erg Gpc^-3. We investigate
Comptonization from (a) the part of the released energy which is thermalized
and (b) the relativistic, remnant radio plasma, which may form a second,
relativistic phase in the inter galactic medium, nearly unobservable for
present day instruments (presence of so called 'radio ghosts'). We find a
thermal Comptonization parameter due to (a) of y = 10^-6 and (b) an optical
depth of relativistic electrons in old radio plasma of tau_rel < 10^-7. If a
substantial fraction of the volume of clusters of galaxies is filled with such
old radio plasma the SZ effect based determination of the Hubble constant is
biased to lower values. Finally, it is shown that a supra-thermal population of
electrons in the Coma cluster would produce a signature in the Wien-tail of the
CMB, which is marginally detectable with a multifrequency measurement by the
Planck satellite. Such a population is expected to exist, since its
bremsstrahlung would explain Coma's recently reported high energy X-ray excess.

</DOC>
<DOC>
<DOCNO> 117411 </DOCNO>
Testing population synthesis models with globular cluster colors


  We have measured an extensive set of UBVRIJHK colors for M31 globular
clusters [Barmby et al. 2000]. We compare the predicted simple stellar
population colors of three population synthesis models to the intrinsic colors
of Galactic and M31 globular clusters. The best-fitting models fit the cluster
colors very well -- the weighted mean color offsets are all < 0.05 mag. The
most significant offsets between model and data are in the U and B passbands;
these are not unexpected and are likely due to problems with the spectral
libraries used by the models. The metal-rich clusters ([Fe/H] > -0.8) are best
fit by young (8 Gyr) models, while the metal-poor clusters are best fit by
older (12--16 Gyr) models. If this range of globular cluster ages is correct,
it implies that conditions for cluster formation must have existed for a
substantial fraction of the galaxies' lifetimes.

</DOC>
<DOC>
<DOCNO> 11973 </DOCNO>
Analysis of Vocal Disorders in a Feature Space


  This paper provides a way to classify vocal disorders for clinical
applications. This goal is achieved by means of geometric signal separation in
a feature space. Typical quantities from chaos theory (like entropy,
correlation dimension and first lyapunov exponent) and some conventional ones
(like autocorrelation and spectral factor) are analysed and evaluated, in order
to provide entries for the feature vectors. A way of quantifying the amount of
disorder is proposed by means of an healthy index that measures the distance of
a voice sample from the centre of mass of both healthy and sick clusters in the
feature space. A successful application of the geometrical signal separation is
reported, concerning distinction between normal and disordered phonation.

</DOC>
<DOC>
<DOCNO> 151508 </DOCNO>
On Discrete Symmetries in su(2) and su(3) Affine Theories and Related


  We classify the possible finite symmetries of conformal field theories with
an affine Lie algebra su(2) and su(3), and discuss the results from the
perspective of the graphs associated with the modular invariants. The
highlights of the analysis are first, that the symmetries we found in either
case are matched by the graph data in a perfect way in the case of su(2), but
in a looser way for su(3), and second, that some of the graphs lead naturally
to projective representations, both in su(2) and in su(3).

</DOC>
<DOC>
<DOCNO> 12551 </DOCNO>
Stability of Repulsive Bose-Einstein Condensates in a Periodic Potential


  The cubic nonlinear Schr\"odinger equation with repulsive nonlinearity and an
elliptic function potential models a quasi-one-dimensional repulsive dilute gas
Bose-Einstein condensate trapped in a standing light wave. New families of
stationary solutions are presented. Some of these solutions have neither an
analog in the linear Schr\"odinger equation nor in the integrable nonlinear
Schr\"odinger equation. Their stability is examined using analytic and
numerical methods. All trivial-phase stable solutions are deformations of the
ground state of the linear Schr\"odinger equation. Our results show that a
large number of condensed atoms is sufficient to form a stable, periodic
condensate. Physically, this implies stability of states near the Thomas-Fermi
limit.

</DOC>
<DOC>
<DOCNO> 119343 </DOCNO>
On the photodissociation of H2 by the first stars


  The first star formation in the universe is expected to take place within
small protogalaxies, in which the gas is cooled by molecular hydrogen. However,
if massive stars form within these protogalaxies, they may suppress further
star formation by photodissociating the H2. We examine the importance of this
effect by estimating the timescale on which significant H2 is destroyed. We
show that photodissociation is significant in the least massive protogalaxies,
but becomes less so as the protogalactic mass increases. We also examine the
effects of photodissociation on dense clumps of gas within the protogalaxy. We
find that while collapse will be inhibited in low density clumps, denser ones
may survive to form stars.

</DOC>
<DOC>
<DOCNO> 116499 </DOCNO>
Efficiency of neutron detection of superheated drops of Freon-22


  Neutron detection efficiency of superheated drops of Freon22 for neutrons
obtained from a 3Ci Am-Be neutron source has been reported in this paper.
Neutron detection efficiency of both F-22 and F-12 have been determined from
the measured nucleation rate using the volumetric method developed in our lab.
The result shows that the neutron detection efficiency of F-22 for the energy
spectrum obtained from Am-Be is almost double, while the life time is 58.6%
smaller than that of F-12, for a particular neutron flux of that source.

</DOC>
<DOC>
<DOCNO> 70642 </DOCNO>
Gaugino-Assisted Anomaly Mediation


  We present a model of supersymmetry breaking mediated through a small extra
dimension. Standard model matter multiplets and a supersymmetry-breaking (or
``hidden'') sector are confined to opposite four-dimensional boundaries while
gauge multiplets live in the bulk. The hidden sector does not contain a singlet
and the dominant contribution to gaugino masses is via anomaly-mediated
supersymmetry breaking. Scalar masses get contributions from both anomaly
mediation and a tiny hard breaking of supersymmetry by operators on the
hidden-sector boundary. These operators contribute to scalar masses at one loop
and in most of parameter space, their contribution dominates. Thus it is easy
to make all squared scalar masses positive. As no additional fields or
symmetries are required below the Planck scale, we consider this the simplest
working model of anomaly mediation. The gaugino spectrum is left untouched and
the phenomenology of the model is roughly similar to anomaly mediated
supersymmetry breaking with a universal scalar mass added. We identify the main
differences in the spectrum between this model and other approaches. We also
discuss mechanisms for generating the mu term and constraints on additional
bulk fields.

</DOC>
<DOC>
<DOCNO> 13142 </DOCNO>
Role of quantum entanglement due to a magnetic impurity on current


  We study the current magnification effect in presence of exchange scattering
of electron from a magnetic impurity placed in one arm of an open mesoscopic
ring. The exchange interaction causes entanglement of electron spin and
impurity spin. Earlier studies have shown that such an entanglement causes
reduction or loss of interference in the Aharonov-Bohm oscillations leading to
decoherence. We find however, that this entanglement, in contradiction to the
naive expectation of a reduction of current magnification, leads to enhancement
as well as suppression of the effect. We also observe additional novel features
like new resonances and current reversals.

</DOC>
<DOC>
<DOCNO> 68348 </DOCNO>
Self-interacting Dark Matter and Invisibly Decaying Higgs


  Self-interacting dark matter has been suggested in order to overcome the
difficulties of the Cold Dark Matter model on galactic scales. We argue that a
scalar gauge singlet coupled to the Higgs boson, which could lead to an
invisibly decaying Higgs, is an interesting candidate for this self-interacting
dark matter particle. We also present estimates on the abundance of these
particles today as well as consequences to non-Newtonian forces.

</DOC>
<DOC>
<DOCNO> 11911 </DOCNO>
Coiling Instability of Multilamellar Membrane Tubes with Anchored


  We study experimentally a coiling instability of cylindrical multilamellar
stacks of phospholipid membranes, induced by polymers with hydrophobic anchors
grafted along their hydrophilic backbone. Our system is unique in that coils
form in the absence of both twist and adhesion. We interpret our experimental
results in terms of a model in which local membrane curvature and polymer
concentration are coupled. The model predicts the occurrence of maximally tight
coils above a threshold polymer occupancy. A proper comparison between the
model and experiment involved imaging of projections from simulated coiled
tubes with maximal curvature and complicated torsions.

</DOC>
<DOC>
<DOCNO> 151690 </DOCNO>
Boundary spectrum in the sine-Gordon model with Dirichlet boundary


  We find the spectrum of boundary bound states for the sine-Gordon model with
Dirichlet boundary conditions, closing the bootstrap and providing a complete
description of all the poles in the boundary reflection factors. The boundary
Coleman-Thun mechanism plays an important role in the analysis. Two basic
lemmas are introduced which should hold for any 1+1-dimensional boundary field
theory, allowing the general method to be applied to other models.

</DOC>
<DOC>
<DOCNO> 8071 </DOCNO>
Decoherence of Schrodinger cat states in a Luttinger liquid


  Schrodinger cat states built from quantum superpositions of left or right
Luttinger fermions located at different positions in a spinless Luttinger
liquid are considered. Their decoherence rates are computed within the
bosonization approach using as environments the quantum electromagnetic field
or two or three dimensionnal acoustic phonon baths. Emphasis is put on the
differences between the electromagnetic and acoustic environments.

</DOC>
<DOC>
<DOCNO> 70921 </DOCNO>
Implications of Configuration Mixing in The Chiral Quark Model With


  The implications of Chiral Quark Model with SU(3) and axial U(1) symmetry
breakings as well as configuration mixing generated by one gluon exchange
forces ($\chi$QM$_{gcm}$) are discussed in context of proton flavor and spin
structure as well as hyperon $\beta$-decay data. Apart from reproducing the
success of $\chi$QM with symmetry breaking, it is able to improve upon the
agreement with data in several cases such as, $G_A/G_V, \Delta_8, <A_1^p>$
dependent on spin polarization functions and ($\frac{2 \bar s}{u+d}$),
($\frac{2 \bar s}{\bar u+\bar d}$) and f_s involving the quark distribution
functions.

</DOC>
<DOC>
<DOCNO> 39884 </DOCNO>
Measurement of B(/\c->pKpi)


  The /\c->pKpi yield has been measured in a sample of two-jet continuum events
containing a both an anticharm tag (Dbar) as well as an antiproton (e+e- ->
Dbar pbar X), with the antiproton in the hemisphere opposite the Dbar. Under
the hypothesis that such selection criteria tag e+e- -> Dbar pbar (/\c) X
events, the /\c->pkpi branching fraction can be determined by measuring the
pkpi yield in the same hemisphere as the antiprotons in our Dbar pbar X sample.
Combining our results from three independent types of anticharm tags, we obtain
B(/\c->pKpi)=(5.0+/-0.5+/-1.2)%

</DOC>
<DOC>
<DOCNO> 8438 </DOCNO>
Perpendicular transport properties of


  The coupling between the superconducting planes of YBa2Cu3O{7-\delta}/
PrBa2Cu3O{7-\delta} superlattices has been measured by c-axis transport. We
show that only by changing the thickness of the superconducting
YBa2Cu3O{7-\delta} layers, it is possible to switch between quasi-particle and
Josephson tunneling. From our data we deduce a low temperature c-axis coherence
length of 0.27 nm.

</DOC>
<DOC>
<DOCNO> 8558 </DOCNO>
Angle-resolved photoemission in high Tc cuprates from theoretical


  The angle-resolved photoemission (ARPES) technique has been developed rapidly
over the last decay, accompanied by the improvement of energy and momentum
resolutions. This technique has been established as the most powerful tool to
investigate the high Tc cuprate superconductors. We review recent ARPES data on
the cuprates from a theoretical point of view, with emphasis on the systematic
evolution of the spectral weight near the momentum (pi,0) from insulator to
overdoped systems. The effects of charge stripes on the ARPES spectra are also
reviewed. Some recent experimental and theoretical efforts to understand the
superconducting state and the pseudogap phenomenon are discussed.

</DOC>
<DOC>
<DOCNO> 102159 </DOCNO>
Countable structure does not have a free uncountable automorphism group


  Solecki proved that the group of automorphisms of a countable structure
cannot be an uncountable free abelian group. See more in Just, Shelah and
Thomas math.LO/0003120 where as a by product we can say something on on
uncountable structures. We prove here the following Theorem: If A is a
countable model, then Aut(M) cannot be a free uncountable group.

</DOC>
<DOC>
<DOCNO> 120946 </DOCNO>
Small-scale structures in Compact Steep-Spectrum and GHz-Peaked-Spectrum


  We determine the small-scale structure for a large sample of Compact Steep
Spectrum (CSS) and Gigahertz Peaked Spectrum (GPS) sources and a sample of
larger radio sources at 327 MHz using the technique of Inter-Planetary
Scintillation (IPS) with the Ooty Radio Telescope. Our observations provide
structural information on angular scales ranging from about 50 to a few hundred
milliarcsec. We estimate the size and flux density of the scintillating
components from the IPS observations. The fraction of flux density of the
hotspots estimated from both the IPS observations as well as from
interferometric observations for larger sources from the literature exhibits no
significant dependence on either the radio luminosity or linear size for the
high-luminosity sources. We examine the collimation of radio jets using the
sizes of hotspots from both IPS and interferometric observations. The hotspot
sizes do not exhibit a significant dependence on the overall linear size for
the larger sources, although the CSS and GPS sources were earlier found to
evolve in a self-similar way. The IPS observations show evidence of
larger-scale structures compared to the known VLBI-scale structures in 8 CSS
and GPS radio sources. We discuss the origin of these structures. We also
examine the spectra of compact components in GPS sources using both IPS and
interferometric measurements, and attempt to distinguish between different
processes for explaining their low-frequency spectra.

</DOC>
<DOC>
<DOCNO> 99515 </DOCNO>
Intersection cohomology on nonrational polytopes


  Viewing a fan as a partially ordered set (of cones) we consider a category of
sheaves on the fan which corresponds to a category of equivariant sheaves on
the corresponding toric variety if the fan is rational. In this category we
define an object which corresponds to the equivariant intersection cohomology
complex. Our first main result is the ``elementary'' decomposition theorem for
the direct image under subdivision of fans We also develop the Borel-Moore-
Verdier duality in the derived category of sheaves on the fan.

</DOC>
<DOC>
<DOCNO> 100573 </DOCNO>
Goldbach's Rule


  Goldbach`s Conjecture, "every even number greater than 2 can be expressed as
the sum of two primes" is renamed Goldbach`s Rule for it can not be otherwise.
The conjecture is proven by showing that the existence of prime pairs adding to
any even number greater than 2 is a natural by-product of the existence of the
prime sequence less than that even number. First it is shown that the remainder
of cancellations process which identifies primes less than an even number also
remainders prime pairs adding to that even number as a natural part of the
process. Then a minimum limit for the remaindered number of prime pairs adding
to an even number is expressed in terms of that even number and shown to exist
for every even number greater than 2. Furthermore, the reasonings and
formulations used in the proof are demonstrated to hold against observations.

</DOC>
<DOC>
<DOCNO> 7863 </DOCNO>
Critical phenomena near the antiferromagnetic quantum critical point of


  We present a study of the critical phenomena around the quantum critical
point in heavy-fermion systems. In the framework of the S=1/2 Kondo lattice
model, we introduce an extended decoupling scheme of the Kondo interaction
which allows one to treat the spin fluctuations and the Kondo effect on an
equal footing. The calculations, developed in a self-consistent one-loop
approximation, lead to the formation of a damped collective mode with a dynamic
exponent z=2 in the case of an antiferromagnetic instability. The system
displays a quantum-classical crossover at finite temperature depending how the
energy of the mode, on the scale of the magnetic correlation length, compares
to k_B T. The low temperature behavior, in the different regimes separated by
the crossover temperatures, is then discussed for both 2- and 3-dimensional
systems.

</DOC>
<DOC>
<DOCNO> 40417 </DOCNO>
A high-Q^2 measurement of the photon structure function F_2^gamma at


  The photon structure function F_2^gamma has been measured at <Q^2> of 706
GeV^2, using a sample of two-photon events with a scattered electron observed
in the OPAL electromagnetic endcap calorimeter. The data were taken during the
years 1997-1999, when LEP operated at e+e- centre-of-mass energies ranging from
183 to 202 GeV, and correspond to an integrated luminosity of 424 pb^-1. This
analysis represents the highest <Q^2> measurement of F_2^gamma made to date.

</DOC>
<DOC>
<DOCNO> 122766 </DOCNO>
MHD jets around galactic objects


  We present a self-similar, steady-state model describing both a magnetized
accretion disc and a magnetohydrodynamic jet. We focus on the role of a hot
corona in such a structure. This corona enables the disc to launch various
types of jets. By considering the energy conservation, we also present a
diagnostic of the luminosity of the magnetized disc, which could explain some
observational signatures of galactic objects.

</DOC>
<DOC>
<DOCNO> 178978 </DOCNO>
Fock-Bargmann space and classic trajectories


  In recent years, a new approach to the theory of nuclear reactions leading to
a break-down of the interacting subsytems into various channels has been
developed. This approach was named the Antisymmetrized Molecular Dynamic (AMD),
and its main idea lies in the description of the nucleons by wave packets in
which the antisymmetrization effects (but not other quantum effects) are
accounted for. In the present review, the basic principles of AMD are
illustrated on the examples of simplest nuclear systems, and the results are
compared with those provided by an exact quantum-mechanical description in the
Fock-Bargmann space. The applicability region of AMD is discussed, in
particular, in the cases of systems with discrete spectrum, and a relation
between the classical AMD trajectories and the quantum distributions is
established. At the same time, a new interpretation of Brink orbitals and
Slater determinants built on them as eigenfunctions of the coordinate operator
defined in the Fock-Bargmann space is proposed. It is shown that these
functions form the cluster geometry of nuclear systems.

</DOC>
<DOC>
<DOCNO> 71857 </DOCNO>
Baryon wave functions in QCD and integrable models


  A new theoretical framework is proposed for the description of baryon
light-cone distribution amplitudes, based on the observation that their scale
dependence to leading logarithmic accuracy is described by a completely
integrable model. The physical interpretation is that one is able to find a new
quantum number that distinguishes partonic components in the nucleon with
different scale dependence.

</DOC>
<DOC>
<DOCNO> 101069 </DOCNO>
Symmetric Hilbert spaces arising from species of structures


  Symmetric Hilbert spaces such as the bosonic and the fermionic Fock spaces
over some `one particle space' $\K$ are formed by certain symmetrization
procedures performed on the full Fock space. We investigate alternative ways of
symmetrization by building on Joyal's notion of a combinatorial species. Any
such species $F$ gives rise to an endofunctor $\G_F$ of the category of Hilbert
spaces with contractions mapping a Hilbert space $\K$ to a symmetric Hilbert
space $\G_F(\K)$ with the same symmetry as the species $F$. A general framework
for annihilation and creation operators on these spaces is developed, and
compared to the generalised Brownian motions of R. Speicher and M. Bo\.zejko.
As a corollary we find that the commutation relation
$a_ia_j^*-a_j^*a_i=f(N)\delta_{ij}$ with $Na_i^*-a_i^*N=a_i^*$ admits a
realization on a symmetric Hilbert space whenever $f$ has a power series with
infinite radius of convergence and positive coefficients.

</DOC>
<DOC>
<DOCNO> 117723 </DOCNO>
The enigmatic Soft X-ray AGN RX J0134.2--4258


  We report the discovery and analysis of the follow-up ROSAT pointed
observation, an ASCA observation and optical and radio observations of the
enigmatic soft X-ray AGN RX J0134.2-4258. In the optical, RX J0134.2-4258
appears as an extreme 'Narrow-Line Seyfert 1 galaxy' (NLS1), with very strong
FeII emission, very blue optical continuum spectrum and almost no Narrow Line
Region emission. While its spectrum was one of the softest observed from an AGN
during the ROSAT All-Sky Survey, its spectrum was found to be dramatically
harder during a pointed observation although the count rate remained constant.
We found in the pointed observation that the spectrum is softer when it is
fainter and spectral fitting demonstrates that it is the hard component that is
variable. The ASCA observation confirms the presence of a hard X-ray power law,
the slope of which is rather flat compared with other NLS1s. Survey and
followup radio observations reveal that RX J0134.2-4258 is also unusual in that
it is a member of the rare class of radio-loud NLS1s, and, with R=71, it holds
the current record for largest radio-to-optical ratio in NLS1s. We discuss
possible scenarios to explain its strange behaviour.

</DOC>
<DOC>
<DOCNO> 10360 </DOCNO>
Metallic behavior and related phenomena in two dimensions


  For about twenty years, it has been the prevailing view that there can be no
metallic state or metal-insulator transition in two dimensions in zero magnetic
field. In the last several years, however, unusual behavior suggestive of such
a transition has been reported in a variety of dilute two-dimensional electron
and hole systems. The physics behind these observations is presently not
understood. We review and discuss the main experimental findings and suggested
theoretical models.

</DOC>
<DOC>
<DOCNO> 119001 </DOCNO>
Variability Model for the Microquasar GRS 1915+105


  We analyse the radiation pressure instability of the standard, optically
thisc disc and propose it as an explanation of the obseved variability of the
superluminal microquasar GRS 1915+105. The quantitave agreement with the
observed outburst amplitudes is obtained under the assumption that substantial
part of the energy is carried away by the jet.

</DOC>
<DOC>
<DOCNO> 150969 </DOCNO>
Enhancons, Fuzzy Spheres and Multi-Monopoles


  We study the `enhancon', a spherical hypersurface apparently made of
D-branes, which arises in string theory studies of large N SU(N) pure gauge
theories with eight supercharges. When the gauge theory is 2+1 dimensional, the
enhancon is an S^2. A relation to charge N BPS multi-monopoles is exploited to
uncover many of its detailed properties. It is simply a spherical slice through
an Atiyah-Hitchin-like submanifold of the charge $N$ BPS monopole moduli space.
In the form of Nahm data, it is built from the N dimensional irreducible
representation of SU(2). In this sense the enhancon is a non-commutative
sphere, reminiscent of the spherical `dielectric' branes of Myers.

</DOC>
<DOC>
<DOCNO> 102410 </DOCNO>
Comment on: Modular Theory and Geometry


  In this note we comment on part of a recent article by B. Schroer and H.-W.
Wiesbrock. Therein they calculate some new modular structure for the
U(1)-current-algebra (Weyl-algebra). We point out that their findings are true
in a more general setting. The split-property allows an extension to
doubly-localized algebras.

</DOC>
<DOC>
<DOCNO> 83305 </DOCNO>
Polynomial-time Computation via Local Inference Relations


  We consider the concept of a local set of inference rules. A local rule set
can be automatically transformed into a rule set for which bottom-up evaluation
terminates in polynomial time. The local-rule-set transformation gives
polynomial-time evaluation strategies for a large variety of rule sets that
cannot be given terminating evaluation strategies by any other known automatic
technique. This paper discusses three new results. First, it is shown that
every polynomial-time predicate can be defined by an (unstratified) local rule
set. Second, a new machine-recognizable subclass of the local rule sets is
identified. Finally we show that locality, as a property of rule sets, is
undecidable in general.

</DOC>
<DOC>
<DOCNO> 99476 </DOCNO>
Scattering theory from microscopic first principles


  We sketch a derivation of abstract scattering theory from the microscopic
first principles defined by Bohmian mechanics. We emphasize the importance of
the flux-across-surfaces theorem for the derivation, and of randomness in the
impact parameter of the initial wave function---even for an, inevitably
inadequate, orthodox derivation.

</DOC>
<DOC>
<DOCNO> 100901 </DOCNO>
How weak is weak extent?


  A space X is star-Lindelof provided for every open cover U there is a finite
subset A of X such that St(A,U)=X. We show that a Tychonoff star-Lindelof space
can have arbitraryly big extent while the extent of a normal star-Lindelof
space can not be greater than c.

</DOC>
<DOC>
<DOCNO> 119184 </DOCNO>
Chandra X-Ray Observatory (CXO):Overview


  The Chandra X-Ray Observatory (CXO), the x-ray component of NASA's Great
Observatories, was launched early in the morning of 1999, July 23 by the Space
Shuttle Columbia. The Shuttle launch was only the first step in placing the
observatory in orbit. After release from the cargo bay, the Inertial Upper
Stage performed two firings, and separated from the observatory as planned.
Finally, after five firings of Chandra's own Integral Propulsion System--- the
last of which took place 15 days after launch--- the observatory was placed in
its highly elliptical orbit of 140,000 km apogee and 10,000 km perigee. After
activation, the first x-rays focussed by the telescope were observed on 1999,
August 12. Beginning with these initial observations one could see that the
telescope had survived the launch environment and was operating as expected.
The month following the opening of the sunshade door was spent adjusting the
focus for each set of instrument configurations, determining the optical axis,
calibrating the star camera, establishing the relative response functions,
determining energy scales, and taking a series of "publicity" images. Each
observation proved to be far more revealing than was expected. Finally, and
despite an initial surprise and setback due to the discovery that the Chandra
x-ray telescope was far more efficient for concentrating low-energy protons
than had been anticipated, the observatory is performing well and is returning
superb scientific data. Together with other space observatories, most notably
the recently activated XMM-Newton, it is clear that we are entering a new era
of discovery in high-energy astrophysics.

</DOC>
<DOC>
<DOCNO> 100021 </DOCNO>
Decompositions of Reflexive Modules


  We continue [GbSh:568] (math.LO/0003164), proving a stronger result under the
special continuum hypothesis (CH). The original question of Eklof and Mekler
related to dual abelian groups. We want to find a particular example of a dual
group, which will provide a negative answer to the question. In order to derive
a stronger and also more general result we will concentrate on reflexive
modules over countable principal ideal domains R. Following H.Bass, an R-module
G is reflexive if the evaluation map s:G-->G^{**} is an isomorphism. Here
G^*=Hom(G,R) denotes the dual group of G. Guided by classical results the
question about the existence of a reflexive R-module G of infinite rank with G
not cong G+R is natural. We will use a theory of bilinear forms on free
R-modules which strengthens our algebraic results in [GbSh:568]
(math.LO/0003164). Moreover we want to apply a model theoretic combinatorial
theorem from [Sh:e] which allows us to avoid the weak diamond principle. This
has the great advantage that the used prediction principle is still similar to
the diamond, but holds under CH.

</DOC>
<DOC>
<DOCNO> 40043 </DOCNO>
Inclusive Photoproduction of Neutral Pions in the Photon Hemisphere at


  The inclusive cross section for the photoproduction of neutral pions has been
measured as a function of the transverse momentum, rapidity, and Feynman x of
the pizero mesons at an average photon--proton centre-of-mass energy of 208 GeV
and for photon virtualities below Q^2=0.01 GeV^2. The pizero measurement
extends the range covered by previous charged particle measurements at HERA by
two units of rapidity in the photon direction down to a value of -5.5 in the
gamma p centre-of-mass frame. The pizero transverse momentum distribution is
well described over the whole measured range by a power law ansatz, while an
exponential fit falls below the data at transverse momentum values above 1.5
GeV/c. Good agreement with the predictions of the Monte Carlo models PYTHIA and
PHOJET is found. In the context of the PYTHIA model the data are inconsistent
with large intrinsic transverse momentum values in the photon.

</DOC>
<DOC>
<DOCNO> 101485 </DOCNO>
Homology TQFT's and the Alexander-Reidemeister Invariant of 3-Manifolds


  We develop an explicit skein theoretical algorithm to compute the Alexander
polynomial of a 3-manifold from a surgery presentation employing the methods
used in the construction of quantum invariants of 3-manifolds. As a
prerequisite we establish and prove a rather unexpected equivalence between the
topological quantum field theory constructed by Frohman and Nicas using the
intersection homology of U(1)-representation varieties on the one side and the
combinatorially constructed Hennings-TQFT based on the quasitriangular Hopf
algebra ${\cal N}=\Z/2\ltimes \ext *\R^2$ on the other side. We find that both
TQFT's are $SL(2,\R)$-equivariant functors and also as such isomorphic. The
$SL(2,\R)$-action in the Hennings construction comes from the natural action on
$\cal N$ and in the case of the Frohman-Nicas theory from the Hard-Lefschetz
decomposition of the U(1)-moduli spaces given that they are naturally K\"ahler.
The irreducible components of this TQFT, corresponding to simple
representations of $SL(2,\Z)$ and $Sp(2g,\Z)$, thus yield a large family of
homological TQFT's by taking sums and products. We give several examples of
TQFT's and invariants that appear to fit into this family, such as Milnor and
Reidemeister Torsion, Seiberg-Witten theories, Casson type theories for
homology circles \'a la Donaldson, higher rank gauge theories following Frohman
and Nicas, and the $\Z/r$ reductions of Reshetikhin-Turaev theories over the
cyclotomic integers $\Z[\zeta_r]$. We also conjecture that the Hennings TQFT
for quantum-${\mathfrak sl}_2$ is the product of the Reshetikhin-Turaev TQFT
and such a homological TQFT.

</DOC>
<DOC>
<DOCNO> 39821 </DOCNO>
Present Situation of Diffracted X-ray Radiation and Resonance (Coherent)


  The review is devoted to the modern investigations of electromagnetic
radiation by relativistic charged particles propagating with constant velocity
through the periodic media. Two examples of radiation are considered in this
review, the first corresponds to the Bragg scattering of charged particles
pseudophotons in crystals, the second one to the Fresnel scattering of
pseudophotons in periodic medium. Both examples play essential role in
construction new compact tunable sources in X-ray region.

</DOC>
<DOC>
<DOCNO> 117440 </DOCNO>
The Circumstellar Matter Around OH44.8-2.3


  I-band images of the OH maser source OH44.8-2.3 are presented. Having a
well-determined distance, this object is shown to be very young and physically
small, with an asymmetric compact bipolar nebula already present. In the
morphological terminology of Meixner et al. (2000) and Ueta et al. (2000), this
object would be classified as a DUPLEX nebula because of its high optical depth
and pole-to-equator density contrast.

</DOC>
<DOC>
<DOCNO> 7720 </DOCNO>
Quantum Projector Method on Curved Manifolds


  A generalized stochastic method for projecting out the ground state of the
quantum many-body Schr\"odinger equation on curved manifolds is introduced.
This random-walk method is of wide applicability to any second order
differential equation (first order in time), in any spatial dimension. The
technique reduces to determining the proper ``quantum corrections'' for the
Euclidean short-time propagator that is used to build up their path-integral
Monte Carlo solutions. For particles with Fermi statistics the ``Fixed-Phase''
constraint (which amounts to fixing the phase of the many-body state) allows
one to obtain stable, albeit approximate, solutions with a variational
property. We illustrate the method by applying it to the problem of an electron
moving on the surface of a sphere in the presence of a Dirac magnetic monopole.

</DOC>
<DOC>
<DOCNO> 39856 </DOCNO>
Signatures of the Induced $\Theta$ vacuum state in Heavy Ion Collisions


  It was argued recently that, in general, an arbitrary induced theta vacuum
state would be created in the heavy ion collisions, similar to the creation of
the disoriented chiral condensatewith an arbitrary isospin direction. It should
be a large domain with a wrong theta orientation which will mimic the physics
of the world when the fundamental theta is non-zero. I suggest a few simple
observables which can (hopefully) be measured on an event by event basis at
RHIC, and which uniquely determine whether the induced theta vacuum state is
created.

</DOC>
<DOC>
<DOCNO> 13386 </DOCNO>
Spectral functions and pseudogap in the t-J model


  We calculate spectral functions within the t-J model as relevant to cuprates
in the regime from low to optimum doping. On the basis of equations of motion
for projected operators an effective spin-fermion coupling is derived. The self
energy due to short-wavelength transverse spin fluctuations is shown to lead to
a modified selfconsistent Born approximation, which can explain strong
asymmetry between hole and electron quasiparticles. The coupling to
long-wavelength longitudinal spin fluctuations governs the low-frequency
behavior and results in a pseudogap behavior, which at low doping effectively
truncates the Fermi surface.

</DOC>
<DOC>
<DOCNO> 170226 </DOCNO>
Joint measurements via quantum cloning


  We explore the possibility of achieving optimal joint measurements of
noncommuting observables on a single quantum system by performing conventional
measurements of commuting self adjoint operators on optimal clones of the
original quantum system. We consider the case of both finite dimensional and
infinite dimensional Hilbert spaces. In the former we study the joint
measurement of three orthogonal components of a spin 1/2, in the latter we
consider the case of the joint measurements of any pair of noncommuting
quadratures of one mode of the electromagnetic field. We show that universally
covariant cloning is not ideal for joint measurements, and a suitable non
universally covariant cloning is needed.

</DOC>
<DOC>
<DOCNO> 118336 </DOCNO>
Interactions as a Driver of Galaxy Evolution


  Gravitational interactions and mergers are shaping and reshaping galaxies
throughout the observable universe. While observations of interacting galaxies
at low redshifts yield detailed information about the processes at work,
observations at high redshifts suggest that interactions and mergers were much
more frequent in the past. Major mergers of nearby disk galaxies form remnants
that share many properties with ellipticals and are, in essence, present-day
protoellipticals. There is also tantalizing evidence that minor mergers of
companions may help build bulges in disk galaxies. Gas plays a crucial role in
such interactions. Because of its dissipative nature, it tends to get crunched
into molecular form, turning into fuel for starbursts and active nuclei.
Besides the evidence for ongoing interactions, signatures of past interactions
and mergers in galaxies abound: tidal tails and ripples, counterrotating disks
and bulges, polar rings, systems of young globular clusters, and aging
starbursts. Galaxy formation and transformation clearly is a prolonged process
occurring to the present time. Overall, the currently available observational
evidence points towards Hubble's morphological sequence being mainly a sequence
of decreasing merger damage.

</DOC>
<DOC>
<DOCNO> 14061 </DOCNO>
String Limit of Vortex Current Algebra


  The Poisson structure generating the hamiltonian dynamics of string vortices
is reconstructed within the current algebra picture as a limiting case of the
standard brackets associated to fluids with a smooth vorticity field. The
approach implemented bypasses the use of Dirac's procedure. The fine structure
of the dynamical algebra is derived for planar fluids by implementing an
appropriate spatial fragmentation of the vorticity field, and the limit to the
point vortex gas is effected. The physical interpretation of the resulting
local currents is provided. Nontrivial differences characterizing the canonical
quantization of point vortices and the current algebra quantization are also
illustrated.

</DOC>
<DOC>
<DOCNO> 117629 </DOCNO>
Four Cometary Belts Associated with the Orbits of Giant Planets: A New


  Using numerical simulations, we examine the structure of a cometary
population near a massive planet, such as a giant planet of the Solar system,
starting with one-planet approximation (the Sun plus one planet). By studying
the distributions of comets in semimajor axis, eccentricity, pericenter, and
apocenter distances, we have revealed several interesting features in these
distributions. The most remarkable ones include (i) spatial accumulation of
comets near the planetary orbit (which we call the `cometary belt') and (ii)
avoidance of resonant orbits by comets. Then we abandon one-planet
approximation and examine as to how a cometary belt is modified when the
influence of all four giant planets is taken into consideration. To this end,
we simulate a stationary distribution of comets, which results from the
gravitational scattering of the Kuiper belt objects on the four giant planets
and accounts for the effects of mean motion resonances. Accounting for the
influence of four giant planets makes the cometary belts overlapping, but
nevertheless keeping almost all their basic features found in one-planet
approximation. In particular, the belts maintain the gaps in the (a,e)- and
(a,i)-space similar to the Kirkwood gaps in the main asteroid belt. We conclude
that the large-scale structure of the Solar system is featured by the four
cometary belts expected to contain 20-30 millions of scattered comets, and only
a tiny fraction of them is currently visible as Jupiter-, Saturn-, etc. family
comets.

</DOC>
<DOC>
<DOCNO> 119156 </DOCNO>
The Stellar Population Histories of Early-Type Galaxies. II. Controlling


  We analyze single-stellar-population (SSP) equivalent parameters for 50 local
elliptical galaxies as a function of their structural parameters. These
galaxies fill a two-dimensional plane in the four-dimensional space of [Z/H],
log t, log $\sigma$, and [E/Fe]. SSP age and velocity dispersion can be taken
as the two independent parameters that specify a galaxy's location in this
``hyperplane.'' The hyperplane can be decomposed into two sub-relations: (1) a
``Z-plane,'' in which [Z/H] is a linear function of log $\sigma$ and log t; and
(2) a relation between [E/Fe] and $\sigma$ in which [E/Fe] is larger in
high-$\sigma$ galaxies. Cluster and field ellipticals follow the same
hyperplane, but their ($\sigma$,t) distributions within it differ. Nearly all
cluster galaxies are old; the field ellipticals span a large range in SSP age.
The tight Mg--$\sigma$ relations of these ellipticals can be understood as
two-dimensional projections of the metallicity hyperplane showing it edge-on;
the tightness of these relations does not necessarily imply a narrow range of
ages at fixed $\sigma$. The relation between [E/Fe] and $\sigma$ is consistent
with a higher effective yield of Type II SNe elements at higher $\sigma$. The
Z-plane is harder to explain and may be a powerful clue to star formation in
elliptical galaxies if it proves to be general. Present data favor a
``frosting'' model in which low apparent SSP ages are produced by adding a
small frosting of younger stars to an older base population. If the frosting
abundances are close to or slightly greater than the base population, simple
two-component models run along lines of constant $\sigma$ in the Z-plane, as
required. This favors star formation from well-mixed pre-enriched gas rather
than unmixed low-metallicity gas from an accreted object. (Abridged)

</DOC>
<DOC>
<DOCNO> 118248 </DOCNO>
Astrophysical Effects Related to Gravity-Induced Electric Polarization


  The calculations in Thomas-Fermi approximation show that in a gravitational
field each cell of ultra dense matter inside celestial bodies obtains a very
small positive electric charge. A celestial body is electrically neutral as a
whole, because the negative electric charge exists at its surface. The positive
volume charge is very small, on the order of magnitude it equals to 10^{-18}e
per atom only. But it is sufficient to explain the occurrence of magnetic
fields of the celestial bodies and the existence of a discrete spectrum of
steady-state values of masses of planets, stars, and pulsars.

</DOC>
<DOC>
<DOCNO> 80948 </DOCNO>
QCD at a Finite Density of Static Quarks


  Recently, cluster methods have been used to solve a variety of sign problems
including those that arise in the presence of fermions. In all cases an
analytic partial re-summation over a class of configurations in the path
integral was necessary. Here the new ideas are illustrated using the example of
QCD at a finite density of static quarks. In this limit the sign problem
simplifies since the fermionic part decouples. Furthermore, the problem can be
solved completely when the gauge dynamics is replaced by a Potts model. On the
other hand in QCD with light quarks the solution will require a partial
re-summation over both fermionic and gauge degrees of freedom. The new approach
points to unexplored directions in the search for a solution to this more
challenging sign problem.

</DOC>
<DOC>
<DOCNO> 13020 </DOCNO>
Super-Radiance and the Unstable Photon Oscillator


  If the damping of a simple harmonic oscillator from a thermally random force
is sufficiently strong, then the oscillator may become unstable. For a photon
oscillator (radiatively damped by electric dipole moments), the instability
leads to a low temperature Hepp-Lieb-Preparata super-radiant phase transition.
The stable oscillator regime is described by the free energy of the
conventional Casimir effect. The unstable (strongly damped) oscillator has a
free energy corresponding to Dicke super-radiance.

</DOC>
<DOC>
<DOCNO> 10224 </DOCNO>
Quasi-one-dimensional spin chains in CuSiO3: an EPR study


  Temperature dependent EPR studies were performed on a single crystal of
CuSiO3.This recently discovered compound is isostructural with the spin-Peierls
compound CuGeO3. The EPR signals show different characteristics than those of
CuGeO3 and aredue to Cu2+ spins located along quasi one-dimensional chains. For
T > 8.2K the spin susceptibility closely follows the predictions of a S=1/2
one-dimensional Heisenberg antiferromagnet with J/kB = 21K. Below T = 8.2K the
spin susceptibility immediately drops to zero indicating long range magnetic
order.

</DOC>
<DOC>
<DOCNO> 9486 </DOCNO>
Glassy dynamics near zero temperature


  We numerically study finite-dimensional spin glasses at low and zero
temperature, finding evidences for (i) strong time/space heterogeneities, (ii)
spontaneous time scale separation and (iii) power law distributions of flipping
times. Using zero temperature dynamics we study blocking, clustering and
persistence phenomena.

</DOC>
<DOC>
<DOCNO> 40441 </DOCNO>
Photon collider at TESLA


  High energy photon colliders (gamma-gamma, gamma-electron) based on backward
Compton scattering of laser light is a very natural addition to e+e- linear
colliders. In this report we consider this option for the TESLA project. Recent
study has shown that the horizontal emittance in the TESLA damping ring can be
further decreased by a factor of four. In this case the gamma-gamma luminosity
luminosity in the high energy part of spectrum can reach (1/3)L_{e+e-}. Typical
cross sections of interesting processes in gamma-gamma collisions are higher
than those in e+e- collisions by about one order of magnitude, so the number of
events in gamma-gamma collisions will be more than that in e+e- collisions.
Photon colliders can, certainly, give additional information and they are the
best for the study of many phenomena. The main question is now the technical
feasibility. The key new element in photon colliders is a very powerful laser
system. An external optical cavity is a promising approach for the TESLA
project. A free electron laser is another option. However, a more
straightforward solution is ``an optical storage ring (optical trap)'' with
diode pumped solid state laser injector which is today technically feasible.
This paper briefly reviews the status of a photon collider based at TESLA, its
possible parameters and existing problems.

</DOC>
<DOC>
<DOCNO> 70119 </DOCNO>
Theories of violation of statistics


  I discuss theories of violations of statistics, including intermediate
statistics, parastatistics, parons, and quons. I emphasize quons, which allow
small violations of statistics. I analyze the quon algebra and its
representations, implications of the algebra including the observables allowed
by the superselection rule separating inequivalent representations of the
symmetric group, the conservation of statistics rules, and the rule for
composite systems of quons. I conclude by raising the question of possible
origins of violations of statistics and of the level at which violations should
be expected if they exist.

</DOC>
<DOC>
<DOCNO> 102812 </DOCNO>
Mirror Symmetry, D-Branes and Counting Holomorphic Discs


  We consider a class of special Lagrangian subspaces of Calabi-Yau manifolds
and identify their mirrors, using the recent derivation of mirror symmetry, as
certain holomorphic varieties of the mirror geometry. This transforms the
counting of holomorphic disc instantons ending on the Lagrangian submanifold to
the classical Abel-Jacobi map on the mirror. We recover some results already
anticipated as well as obtain some highly non-trivial new predictions.

</DOC>
<DOC>
<DOCNO> 8165 </DOCNO>
Conductivity Due to Classical Phase Fluctuations in a Model For High-T_c


  We consider the real part of the conductivity, \sigma_1(\omega), arising from
classical phase fluctuations in a model for high-T_c superconductors. We show
that the frequency integral of that conductivity, \int_0^\infty \sigma_1
d\omega, is non-zero below the superconducting transition temperature $T_c$,
provided there is some quenched disorder in the system. Furthermore, for a
fixed amount of quenched disorder, this integral at low temperatures is
proportional to the zero-temperature superfluid density, in agreement with
experiment. We calculate \sigma_1(\omega) explicitly for a model of overdamped
phase fluctuations.

</DOC>
<DOC>
<DOCNO> 100649 </DOCNO>
Stochastic monotonicity and realizable monotonicity


  We explore and relate two notions of monotonicity, stochastic and realizable,
for a system of probability measures on a common finite partially ordered set
(poset) S when the measures are indexed by another poset A. We give
counterexamples to show that the two notions are not always equivalent, but for
various large classes of S we also present conditions on the poset A that are
necessary and sufficient for equivalence. When A = S, the condition that the
cover graph of S have no cycles is necessary and sufficient for equivalence.
This case arises in comparing applicability of the perfect sampling algorithms
of Propp and Wilson and the first author of the present paper.

</DOC>
<DOC>
<DOCNO> 169996 </DOCNO>
The Pauli Equation for Probability Distributions


  The "marginal" distributions for measurable coordinate and spin projection is
introduced. Then, the analog of the Pauli equation for spin-1/2 particle is
obtained for such probability distributions instead of the usual wave
functions. That allows a classical-like approach to quantum mechanics. Some
illuminating examples are presented.

</DOC>
<DOC>
<DOCNO> 11749 </DOCNO>
Quantum phonons and the charge density wave transition temperature: a


  We use the dynamical mean-field method to calculate the charge density wave
transition temperature of the half-filled Holstein model as function of typical
phonon frequency in the physically relevant adiabatic limit of phonon frequency
Omega much less than electron bandwidth t. Our work is the first systematic
expansion of the charge density wave problem in Omega/t. Quantum phonon effects
are found to suppress Tco severely, in agreement with previous work on one
dimensional models and numerical studies of the dynamical mean field model in
the extreme antiadiabatic limit (Omega ~ t). We suggest that this is why there
are very few CDW systems with mean-field transition temperatures much less than
a typical phonon frequency.

</DOC>
<DOC>
<DOCNO> 83462 </DOCNO>
On-the-fly Query-Based Debugging with Examples


  Program errors are hard to find because of the cause-effect gap between the
time when an error occurs and the time when the error becomes apparent to the
programmer. Although debugging techniques such as conditional and data
breakpoints help to find error causes in simple cases, they fail to effectively
bridge the cause-effect gap in many situations. Query-based debuggers offer
programmers an effective tool that provides instant error alert by continuously
checking inter-object relationships while the debugged program is running. To
enable the query-based debugger in the middle of program execution in a
portable way, we propose efficient Java class file instrumentation and discuss
alternative techniques. Although the on-the-fly debugger has a higher overhead
than a dynamic query-based debugger, it offers additional interactive power and
flexibility while maintaining complete portability. To speed up dynamic query
evaluation, our debugger implemented in portable Java uses a combination of
program instrumentation, load-time code generation, query optimization, and
incremental reevaluation. This paper discusses on-the-fly debugging and
demonstrates the query-based debugger application for debugging Java gas tank
applet as well as SPECjvm98 suite applications.

</DOC>
<DOC>
<DOCNO> 174455 </DOCNO>
Cross-sections of spallation residues produced in 1.A GeV 208Pb on


  Spallation residues produced in 1 GeV per nucleon $^{208}$Pb on proton
reactions have been studied using the FRagment Separator facility at GSI.
Isotopic produc- tion cross-sections of elements from $_{61}$Pm to $_{82}$Pb
have been measured down to 0.1 mb with a high accuracy. The recoil kinetic
energies of the produced fragments were also determined. The obtained
cross-sections agree with most of the few existing gamma-spectroscopy data.
Data are compared with different intra nuclear-cascade and evaporation-fission
models. Drastic deviations were found for a standard code used in technical
applications.

</DOC>
<DOC>
<DOCNO> 40331 </DOCNO>
Design and Construction of the 3.2 Mev High Voltage Column for Darht II


  A 3.2 MeV injector has been designed and built for the Darht II Project at
Los Alamos Lab. The installation of the complete injector system is nearing
completion at this time. The requirements for the injector are to produce a 3.2
MeV, 2000 ampere electron pulse with a flattop width of at least 2-microseconds
and emittance of less than 0.15 p cm-rad normalized. A large high voltage
column has been built and installed. The column is vertically oriented, is 4.4
meters long, 1.2 meters in diameter, and weights 5700 kilograms. A novel method
of construction has been employed which utilizes bonded mycalex insulating
rings. This paper will describe the design, construction, and testing completed
during construction. Mechanical aspects of the design will be emphasized.

</DOC>
<DOC>
<DOCNO> 99940 </DOCNO>
On symmetries in Galilei classical mechanics


  In the framework of Galilei classical mechanics (i.e., general relativistic
classical mechanics on a spacetime with absolute time) developed by Jadczyk and
Modugno, we analyse systematically the relations between symmetries of the
geometric objects. We show that the (holonomic) infinitesimal symmetries of the
cosymplectic structure on spacetime and of its potentials are also symmetries
of spacelike metric, gravitational and electromagnetic fields, Euler-Lagrange
morphism, Lagrangians. Then, we provide a covariant momentum map associated
with a group of cosymplectic symmetries by using a covariant lift of functions
of phase space. In the case of an action that projects on spacetime we see that
the components of this momentum map are quantisable functions in the sense of
Jadczyck and Modugno. Finally, we illustrate the results in some examples.

</DOC>
<DOC>
<DOCNO> 174583 </DOCNO>
Nuclear Halo and Molecular States


  Significant advances have been made in recent years in the exploration of
clustering in light nuclei. This progress has arisen not only from the
investigation of new systems, but also through the development and application
of novel probes. This paper will briefly review selected topics concerning halo
and molecular states in light nuclei through examples provided by the
neutron-rich Be isotopes.

</DOC>
<DOC>
<DOCNO> 117769 </DOCNO>
Competitive Accretion in Clusters and the IMF


  Observations have revealed that most stars are born in clusters. As these
clusters typically contain more mass in gas than in stars, accretion can play
an important role in determining the final stellar masses. Numerical
simulations of gas accretion in stellar clusters have found that the stars
compete for the available reservoir of gas. The accretion rates are highly
nonuniform and are determined primarily by each star's position in the cluster.
Stars in the centre accrete more gas, resulting in initial mass segregation.
This competitive accretion naturally results in a mass spectrum and is
potentially the dominant mechanism for producing the initial mass function.
Furthermore, accretion on to the core of a cluster forces it to shrink, which
may result in formation of massive stars through collisions.

</DOC>
<DOC>
<DOCNO> 84590 </DOCNO>
Rigidly rotating dust in general relativity


  A solution to the Einstein field equations that represents a rigidly rotating
dust accompanied by a thin matter shell of the same type is found.

</DOC>
<DOC>
<DOCNO> 122394 </DOCNO>
The stellar content of the Hamburg/ESO survey. I. Automated selection of


  We describe automatic procedures for the selection of DA white dwarfs in the
Hamburg/ESO objective-prism survey (HES). For this purpose, and the selection
of other stellar objects (e.g., metal-poor stars and carbon stars), a flexible,
robust algorithm for detection of stellar absorption and emission lines in the
digital spectra of the HES was developed. Broad band (U-B, B-V) and narrow band
(Str\"omgren c_1) colours can be derived directly from HES spectra, with
precisions of sigma(U-B)=0.092mag; sigma(B-V)=0.095mag; sigma(c_1)=0.15mag.
  We describe simulation techniques that allow to convert model or slit spectra
to HES spectra. These simulated objective-prism spectra are used to determine
quantitative selection criteria, and for the study of selection functions. We
present an atlas of simulated HES spectra of DA and DB white dwarfs.
  Our current selection algorithm is tuned to yield maximum efficiency of the
candidate sample (minimum contamination with non-DAs). DA candidates are
selected in the B-V versus U-B and c_1 versus W_\lambda(Hbeta+Hgamma+Hdelta)
parameter spaces. The contamination of the resulting sample with hot subdwarfs
is expected to be as low as ~8%, while there is essentially no contamination
with main sequence or horizontal branch stars. We estimate that with the
present set of criteria, ~80% of DAs present in the HES database are recovered.
A yet higher degree of internal completeness could be reached at the expense of
higher contamination. However, the external completeness is limited by
additional losses caused by proper motion effects and the epoch differences
between direct and spectral plates used in the HES.

</DOC>
<DOC>
<DOCNO> 150645 </DOCNO>
Knot Theory from a Chern-Simons Gauge Theory Point of View


  A brief summary of the development of perturbative Chern-Simons gauge theory
related to the theory of knots and links is presented. Emphasis is made on the
progress achieved towards the determination of a general combinatorial
expression for Vassiliev invariants. Its form for all the invariants up to
order four is reviewed, and a table of their values for all prime knots with
ten crossings is presented.

</DOC>
<DOC>
<DOCNO> 70221 </DOCNO>
Theoretical Challenges for a Precision Measurement of the W Mass at


  We discuss the O(alpha) electroweak radiative corrections to W and Z boson
production and their impact on the measurement of the W mass at hadron
colliders. The results of recent improved calculations are presented. We also
briefly discuss the O(alpha) corrections to Drell-Yan production in the high
invariant mass region.

</DOC>
<DOC>
<DOCNO> 121066 </DOCNO>
The peculiar motions of early-type galaxies in two distant regions -


  We present peculiar velocities for 84 clusters of galaxies in two large
volumes at distances between 6000 and 15000 km/s in the directions of
Hercules-Corona Borealis and Perseus-Pisces-Cetus. These velocities are based
on Fundamental Plane (FP) distance estimates for early-type galaxies in each
cluster. We fit the FP using a maximum likelihood algorithm which accounts for
both selection effects and measurement errors, and yields FP parameters with
smaller bias and variance than other fitting procedures. We find a best-fit FP
with coefficients consistent with the best existing determinations. We measure
the bulk motions of the sample volumes using the 50 clusters with the
best-determined peculiar velocities. We find the bulk motions in both regions
are small, and consistent with zero at about the 5% level. The EFAR results are
in agreement with the small bulk motions found by Dale et al. (1999) on similar
scales, but are inconsistent with pure dipole motions having the large
amplitudes found by Lauer & Postman (1994) and Hudson et al. (1999). The
alignment of the EFAR sample with the Lauer & Postman dipole produces a strong
rejection of a large-amplitude bulk motion in that direction, but the rejection
of the Hudson et al. result is less certain because their dipole lies at a
large angle to the main axis of the EFAR sample. We find the bulk motion of our
sample is consistent with most cosmological models that approximately reproduce
the shape and normalisation of the observed galaxy power spectrum. We conclude
that existing measurements of large-scale bulk motions provide no significant
evidence against standard models for the formation of structure.

</DOC>
<DOC>
<DOCNO> 178666 </DOCNO>
Squeeze-out of nuclear matter in peripheral heavy-ion collisions and


  We perform a systematic study of in-plane and out-of-plane proton and neutron
flow from nucleus-nucleus collisions within the BUU transport approach
employing different parameter sets for the mean-field potentials that can be
characterized by the nuclear incompressibility and the stiffness of the
momentum-dependent potential. We find that a simultaneous description of the
experimental data from the BEVALAC and the SIS on both the nucleon squeeze-out
$v_2$ and the in-plane flow $F$ at beam energies $E_{lab} = 0.15 \div 2$ AGeV
requires a mean field with strong momentum dependence, i.e. an effective Landau
mass $m^* \simeq 0.68 m_0$ at normal nuclear matter density $\rho_0=0.17$
fm$^{-3}$, where $m_0=0.938$ GeV is the bare nucleon mass. Some experimental
data on the squeeze-out require an even stiffer momentum dependence ($m^*
\approx 0.62 m_0$). All systems investigated are found to be compatible with
$m^*/m_0 = 0.65 \pm 0.03$.

</DOC>
<DOC>
<DOCNO> 39717 </DOCNO>
NNLO Unquenched Calculation of the b Quark Mass


  By combining the first unquenched lattice computation of the B-meson binding
energy and the two-loop contribution to the lattice HQET residual mass, we
determine the (\bar{{MS}}) (b)-quark mass, (\bar{m}_{b}(\bar{m}_{b})). The
inclusion of the two-loop corrections is essential to extract
(\bar{m}_{b}(\bar{m}_{b})) with a precision of ({\cal
O}(\Lambda^{2}_{QCD}/m_{b})), which is the uncertainty due to the renormalon
singularities in the perturbative series of the residual mass. Our best
estimate is (\bar{m}_{b}(\bar{m}_{b}) = (4.26 \pm 0.09) {\rm GeV}), where we
have combined the different errors in quadrature. A detailed discussion of the
systematic errors contributing to the final number is presented. Our results
have been obtained on a sample of (60) lattices of size (24^{3}\times 40) at
(\beta =5.6), using the Wilson action for light quarks and the lattice HQET for
the (b) quark, at two values of the sea quark masses. The quark propagators
have been computed using the unquenched links generated by the T(\chi)L
Collaboration.

</DOC>
<DOC>
<DOCNO> 120114 </DOCNO>
Quasar Str\"omgren Spheres Before Cosmological Reionization


  Ionizing sources embedded in the neutral intergalactic medium (IGM) before
cosmological reionization generate discrete HII regions. We show that a
sufficiently bright quasar (for example, one tenth as luminous as that recently
discovered by Fan et al.) can ionize a large volume, allowing the transmission
of a substantial fraction of the flux of its intrinsic Lyman alpha emission
line on both sides of the Lyman alpha wavelength. The observed line profile is
richly informative. We show that a sufficiently accurate, high spectral
resolution ($R\approx 10^4$) measurement of the line profile of a bright quasar
is feasible using the Next Generation Space Telescope (NGST) as well as large
ground-based telescopes. Such a measurement has two potentially important
applications. First, the red side of the Lyman alpha emission line provides a
way to measure the quasar lifetime. Second, the blue side provides a direct
measure of the density fluctuations of the intergalactic medium at the quasar
redshift. The estimate of the absorption of the red side is limited by the
accuracy to which the intrinsic profile of the Lyman alpha emission line is
known. The blue side, however, does not sensitively depend on the intrinsic
profile, because the former is much narrower than the latter.

</DOC>
<DOC>
<DOCNO> 84284 </DOCNO>
Type II Critical Collapse of a Self-Gravitating Nonlinear $\sigma$-Model


  We report on the existence and phenomenology of type II critical collapse
within the one-parameter family of SU(2) $\sigma$-models coupled to gravity.
Numerical investigations in spherical symmetry show discretely self-similar
(DSS) behavior at the threshold of black hole formation for values of the
dimensionless coupling constant $\ccbeta$ ranging from 0.2 to 100; at 0.18 we
see small deviations from DSS. While the echoing period $\Delta$ of the
critical solution rises sharply towards the lower limit of this range, the
characteristic mass scaling has a critical exponent $\gamma$ which is almost
independent of $\ccbeta$, asymptoting to $0.1185 \pm 0.0005$ at large
$\ccbeta$. We also find critical scaling of the scalar curvature for
near-critical initial data. Our numerical results are based on an
outgoing-null-cone formulation of the Einstein-matter equations, specialized to
spherical symmetry. Our numerically computed initial-data critical parameters
$p^*$ show 2nd order convergence with the grid resolution, and after
compensating for this variation in $p^*$, our individual evolutions are
uniformly 2nd order convergent even very close to criticality.

</DOC>
<DOC>
<DOCNO> 85480 </DOCNO>
Black holes with toroidal, cylindrical and planar horizons in anti-de


  We review the toroidal, cylindrical and planar black hole solutions in
anti-de Sitter spacetimes and present their properties.

</DOC>
<DOC>
<DOCNO> 70175 </DOCNO>
Dynamics of the chiral phase transition at finite chemical potential


  We study the dynamics of the chiral phase transition at finite chemical
potential in the Gross-Neveu model in the leading order in large-N
approximation. We consider evolutions starting in local thermal equilibrium in
the massless unbroken phase for conditions pertaining to traversing a first or
second order phase transition. We assume boost invariant kinematics and
determine the evolution of the the order parameter $\sigma$, the energy density
and pressure as well as the effective temperature, chemical potential and
interpolating number densities as a function of $\tau$.

</DOC>
<DOC>
<DOCNO> 71685 </DOCNO>
Heavy Quark Production in Hadron Collisions


  We compare the numerical predictions for heavy quark production in high
energy hadron collisions in the conventional QCD parton model and the
k_T-factorization approach (semihard theory). The total production cross
sections, one-particle rapidity and p_T distributions as well as several
two-particle correlations are considered. Some of them can help to estimate QCD
scale. The differense in the predictions of the two approaches is not very
large, while the shapes of the distributions are sometimes different.

</DOC>
<DOC>
<DOCNO> 13698 </DOCNO>
All electron and pseudopotential study of the spin polarization of the V


  The spin-polarization at the V(001) surface has been studied by using
different local (LSDA) and semilocal (GGA) approximations to the
exchange-correlation potential of DFT within two ab initio methods: the
all-electron TB-LMTO-ASA and the pseudopotential LCAO code SIESTA (Spanish
Initiative for Electronic Simulations with Thousands of Atoms). A comparative
analysis is performed first for the bulk and then for a N-layer V(001) film (7
< N < 15). The LSDA approximation leads to a non magnetic V(001) surface with
both theoretical models in agreement (disagreement) with magneto-optical Kerr
(electron-capture spectroscopy) experiments. The GGA within the pseudopotential
method needs thicker slabs than the LSDA to yield zero moment at the central
layer, giving a high surface magnetization (1.70 Bohr magnetons), in contrast
with the non magnetic solution obtained by means of the all-electron code.

</DOC>
<DOC>
<DOCNO> 122374 </DOCNO>
Search for Microflaring Activity in the Magnetic Network


  We analyze the temporal behavior of Network Bright Points (NBPs) searching
for low-atmosphere signatures of flares occuring on the magnetic network. We
make use of a set of data acquired during coordinated observations between
ground based observatories (NSO/Sacramento Peak) and the MDI instrument onboard
SOHO. Light curves in chromospheric spectral lines show only small amplitude
temporal variations, without any sudden intensity enhancement that could
suggest the presence of a transient phenomenon such as a (micro) flare. Only
one NBP shows spikes of downward velocity, of the order of 2 - 4 Km/s,
considered as signals of compression associated to a (micro) flare occurrence.
For this same NBP, we also find a peculiar relationship between the magnetic
and velocity fields fluctuations, as measured by MDI. Only for this point the B
- V fluctuations are well correlated, suggesting the presence of magneto
acoustic waves propagating along the magnetic structure. This correlation is
lost during the compression episodes and resumes afterward. An A6 GOES soft
X-ray burst is temporally associated with the downward velocity episodes,
suggesting that this NBP is the footpoint of the flaring loop. This event has a
total thermal energy content of about $10^{28}$ erg, and hence belongs to the
microflare class.

</DOC>
<DOC>
<DOCNO> 71514 </DOCNO>
Asymptotic deconfinement in high-density QCD


  We discuss QCD with two light flavors at large baryon chemical potential mu.
Color superconductivity leads to partial breaking of the color SU(3) group. We
show that the infrared physics is governed by the gluodynamics of the remaining
SU(2) group with an exponentially soft confinement scale Lambda_QCD'
Delta*exp[-a*mu/(g*Delta)], where Delta<<mu is the superconducting gap, g is
the strong coupling, and a=0.81... We estimate that at moderate baryon
densities Lambda_QCD' is O(10 MeV) or smaller. The confinement radius increases
exponentially with density, leading to "asymptotic deconfinement." The velocity
of the SU(2) gluons is small due to the large dielectric constant of the
medium.

</DOC>
<DOC>
<DOCNO> 7820 </DOCNO>
Stripes: Why hole rich lines are antiphase domain walls?


  For stripes of hole rich lines in doped antiferromagnets, we investigate the
competition between anti-phase and in-phase domain wall ground state
configurations. We argue that a phase transition must occure as a function of
the electron/hole filling fraction of the domain wall. Due to {\em transverse}
kinetic hole fluctuations, empty domain walls are always anti-phase. At
arbitrary electron filling fraction ($\delta $) of the domain wall (and in
particular for $\delta \approx 1/4$ as in LaNdSrCuO), it is essential to
account also for the transverse magnetic interactions of the electrons and
their mobility {\em along} the domain wall.
  We find that the transition from anti-phase to in-phase stripe domain wall
occurs at a critical filling fraction $0.28<\delta_{c}<0.30$, for any value of
$\frac{J}{t}<{1/3}$. We further use our model to estimate the spin-wave
velocity in a stripe system. Finally, relate the results of our microscopic
model to previous Landau theory approach to stripes.

</DOC>
<DOC>
<DOCNO> 12503 </DOCNO>
Application of two-parameter dynamical replica theory to retrieval


  The two-parameter dynamical replica theory (2-DRT) is applied to investigate
retrieval properties of non-monotonic associative memory, a model which lacks
thermodynamic potential functions. 2-DRT reproduces dynamical properties of the
model quite well, including the capacity and basin of attraction.
Superretrieval state is also discussed in the framework of 2-DRT. The local
stability condition of the superretrieval state is given, which provides a
better estimate of the region in which superretrieval is observed
experimentally than the self-consistent signal-to-noise analysis (SCSNA) does.

</DOC>
<DOC>
<DOCNO> 170752 </DOCNO>
Negativity and Concurrence of mixed 2X2 states


  We consider two measures of entanglement of mixed bipartite states of
dimension 2X2: concurrence and negativity. We first prove the conjecture of
Eisert and Plenio that concurrence can never be smaller than negativity. We
then characterise all states for which concurrence equals negativity and also
those states for which the difference between concurrence and negativity is
maximal (keeping either the concurrence fixed, or the participation ratio
R=1/trace(rho^2)).

</DOC>
<DOC>
<DOCNO> 9557 </DOCNO>
The Properties of Matter in White Dwarfs and Neutron Stars


  White dwarfs and neutron stars are stellar objects with masses comparable to
that of our sun. However, as the endpoint stages of stellar evolution, these
objects do not sustain any thermonuclear burning and therefore can no longer
support the gravitational load of their own mass by generating thermal
pressure. Rather, matter in their interiors is compressed to much higher
densities than commonly found in normal stars, and pressure is created by
degenerate fermion kinetic energy and particle interactions. As a result, white
dwarfs and neutron stars offer unique cosmic laboratories for studying matter
at very high densities. In this review we discuss the basic properties of
condensed matter at extreme densities and summarize the extent to which these
properties can be examined by observations of compact objects.

</DOC>
<DOC>
<DOCNO> 40112 </DOCNO>
"Four Ways to TeV Scale", Ankara'97 Workshop and Something Else


  The first Part contains the invited talk given at the First International
Workshop on Linac-Ring Type ep and $gamma$p Colliders (9-11 April 1997, Ankara,
Turkey). Four known types of colliders, which may give an opportunity to
achieve TeV center of mass energies in the near future (10-15 years), are
discussed. Parameters of the linac-ring type e-p, $gamma$-p, e-nucleus and
$gamma$-nucleus machines are roughly estimated. Some speculations on TeV scale
physics are given. The physics goals of the TeV energy $gamma$-p and
$gamma$-nucleus colliders are considered. Information about the Ankara'97
Workshop, including Workshop Conclusion and Recommendations, is presented in
Part II. Finally, an Appeal to ICFA, ECFA and ACFA is presented in Part III.

</DOC>
<DOC>
<DOCNO> 68949 </DOCNO>
A three generation oscillation analysis of the Super-Kamiokande


  In this paper we do a three-generation oscillation analysis of the latest
(848 days) Super-Kamiokande (SK) atmospheric neutrino data going beyond the one
mass scale dominance (OMSD) approximation. We fix $\Delta_{12} = \Delta_{13}$
($\Delta_{LSND}$) in the range 0.5 - 2 eV$^2$ as allowed by the results from
LSND and other accelerator and reactor experiments on neutrino oscillation and
keep $\Delta_{23}$ ($\Delta_{ATM}$) and the three mixing angles as free
parameters. In such a scenario, the oscillation probabilities for the
accelerator and reactor neutrinos involve only two of the mixing angles
 $\theta_{12}$ and $\theta_{13}$ and one mass scale. But the atmospheric
neutrino oscillation is in general governed by both mass scales and all the
three mixing angles. The higher mass scale gives rise to $\Delta m^2$
independent average oscillations for atmospheric neutrinos and does not enter
the $\chi^2$ analysis as an independent parameter. The $\Delta_{23}$ and the
three mixing angles on the other hand appear as independent parameters in the
$\chi^2$ analysis and the best-fit values of these are determined from an
analysis of a) the SK data, b) the SK and CHOOZ data. The allowed values of the
mixing angles $\theta_{12}$ and $\theta_{13}$ from the above analysis are
compared with the constraints from LSND and other accelerator and reactor
experiments. Implications for future long baseline experiments are discussed.

</DOC>
<DOC>
<DOCNO> 102796 </DOCNO>
Counting Paths in Graphs


  We give a simple combinatorial proof of a formula that extends a result by
Grigorchuk (rediscovered by Cohen) relating cogrowth and spectral radius of
random walks. Our main result is an explicit equation determining the number of
`bumps' on paths in a graph: in a $d$-regular (not necessarily transitive)
non-oriented graph let the series $G(t)$ count all paths between two fixed
points weighted by their length $t^{length}$, and $F(u,t)$ count the same
paths, weighted as $u^{number of bumps}t^{length}$. Then one has
$$F(1-u,t)/(1-u^2t^2) = G(t/(1+u(d-u)t^2))/(1+u(d-u)t^2).$$ We then derive the
circuit series of `free products' and `direct products' of graphs. We also
obtain a generalized form of the Ihara-Selberg zeta function.

</DOC>
<DOC>
<DOCNO> 150712 </DOCNO>
Wilson Loops in N=4 Supersymmetric Yang--Mills Theory


  Perturbative computations of the expectation value of the Wilson loop in N=4
supersymmetric Yang-Mills theory are reported. For the two special cases of a
circular loop and a pair of anti-parallel lines, it is shown that the sum of an
infinite class of ladder-like planar diagrams, when extrapolated to strong
coupling, produces an expectation value characteristic of the results of the
AdS/CFT correspondence, $<W>\sim\exp((constant)\sqrt{g^2N})$. For the case of
the circular loop, the sum is obtained analytically for all values of the
coupling. In this case, the constant factor in front of $\sqrt{g^2N}$ also
agrees with the supergravity results. We speculate that the sum of diagrams
without internal vertices is exact and support this conjecture by showing that
the leading corrections to the ladder diagrams cancel identically in four
dimensions. We also show that, for arbitrary smooth loops, the ultraviolet
divergences cancel to order $g^4N^2$.

</DOC>
<DOC>
<DOCNO> 10002 </DOCNO>
Generation and evolution of vortex-antivortex pairs in Bose-Einstein


  We propose a method for generating and controlling a spatially separated
vortex--antivortex pair in a Bose-Einstein condensate trapped in a toroidal
potential. Our simulations of the time dependent Gross-Pitaevskii equation show
that in toroidal condensates vortex dynamics are different from the dynamics in
the homogeneous case. Our numerical results agree well with analytical
calculations using the image method. Our proposal offers an effective example
of coherent generation and control of vortex dynamics in atomic condensates.

</DOC>
<DOC>
<DOCNO> 169986 </DOCNO>
Supersymmetric and Shape-Invariant Generalization for Non-resonant


  A class of shape-invariant bound-state problems which represent transitions
in a two-level system introduced earlier are generalized to include arbitrary
energy splittings between the two levels. We show that the coupled-channel
Hamiltonians obtained correspond to the generalization of the non-resonant
Jaynes-Cummings Hamiltonian, widely used in quantized theories of laser. In
this general context, we determine the eigenstates, eigenvalues, the time
evolution matrix and the population inversion matrix factor.

</DOC>
<DOC>
<DOCNO> 69108 </DOCNO>
Can LSND be included in a 3-Neutrino framework?


  We study the special features emerging from a three lepton generation
analysis of the available neutrino oscillation data (solar, atmospheric and
LSND). First we find that it is possible to explain all three sets of data in
terms of the standard left handed neutrinos without the need of sterile
neutrinos. Second we find a significant difference in the mass matrix extracted
from the data, depending on the analysis (without or with LSND), if the mass of
the lightest neutrino, which cannot be determined from the neutrino oscillation
data alone, is relatively small, i.e $\leq$0.1 eV. To compare with other
processes we used the R-parity violating Minimal Supersymmetric Standard Model
(\rp-MSSM) for the theoretical description of the neutrino masses. Using the
oscillation data we were able to constrain the parameters of the model. In
particular we were able to obtain values for the coupling constants of the
\rp-MSSM.

</DOC>
<DOC>
<DOCNO> 85334 </DOCNO>
The fading of SN 1997D


  We present a new set of spectroscopic and photometric data extending the
observations of SN 1997D to over 400 days after the explosion. These
observations confirm the peculiar properties of SN 1997D, such as the very low
abundance of 56Co (0.002 Msolar) and the low expansion velocity of the ejecta
(~1000 km/s). We discuss the implications of these observations for the
character of the progenitor and the nature of the remnant showing that a
Crab-like pulsar or an accreting neutron star formed in the explosion of a low
mass progenitor should already have produced a detectable luminosity at this
epoch, in contrast with photometric data. On the other hand, the explosion of a
high mass progenitor with the formation of a black hole is consistent with the
available observations. The consequences of this conclusion regarding the
nature of the explosion and the prospects of directly identifying the black
hole are also addressed.

</DOC>
<DOC>
<DOCNO> 99654 </DOCNO>
Continuous time evolution from iterated maps and Carleman linearization


  Using the Carleman linearization technique the continuous iteration of a
mapping is studied. Based on the detailed analysis of the Carleman embedding
matrix the precise mathematical meaning is given to such notion. The ordinary
differential equations referring to continuous iterations are identified and
the discussion of the relationship between them and the corresponding iterated
maps is performed.
  Keywords: iterated systems, functional eigenequation

</DOC>
<DOC>
<DOCNO> 102081 </DOCNO>
From Mennicke symbols to Euler class groups


  Bhatwadekar and Raja Sridharan have constructed a homomorphism of abelian
groups from an orbit set Um(n,A)/E(n,A) of unimodular rows to an Euler class
group. We suggest that this is the last map in a longer exact sequence of
abelian groups. The hypothetical group G that precedes Um(n,A)/E(n,A) in the
sequence is an orbit set of unimodular two by n matrices over the ring A. If n
is at least four we describe a partially defined operation on two by n
matrices. We conjecture that this operation describes a group structure on G if
A has Krull dimension at most 2n-6. We prove that G is mapped onto a subgroup
of Um(n,A)/E(n,A) if A has Krull dimension at most 2n-5.

</DOC>
<DOC>
<DOCNO> 100449 </DOCNO>
The Configuration space integral for links and tangles in R^3


  The perturbative expression of Chern-Simons theory for links in Euclidean
3-space is a linear combination of integrals on configuration spaces. This has
successively been studied by Guadagnini, Martellini and Mintchev, Bar-Natan,
Kontsevich, Bott and Taubes, D. Thurston, Altschuler and Freidel, Yang... We
give a self-contained version of this study with a new choice of
compactification, and we formulate a rationality result. Then we generalise the
construction to braids and tangles by constructing the suitable limit of the
configuration spaces when we stretch the braid or tangle to a vertical line. We
show that the limit integral is multiplicative and we define the corresponding
connection. We also define a braiding and an associator which determine our
limit for tangles. The braiding is given as a function of the Bott and Taubes
anomaly. If the anomaly was zero in degrees >4, then our limit integral for
links would be equal to the Kontsevich integral.
  This article is a new version of the two preprints math.GT/9901028 and
math.GT/9902058, which contained all the main ideas except for the degree 3
anomaly and the Vassiliev universal property.

</DOC>
<DOC>
<DOCNO> 102531 </DOCNO>
On the determination of 2-step solvable Lie algebra from its weight


  By using the concept of weight graph associated to certain nilpotent Lie
algebras $\frak{g}$, we find necessary and sufficient conditions for a
semidirect product $\frak{g}\oplus T_{i}$, where $T_{i}<T$ is a subalgebra of a
maximal torus of derivations $T$ of $\frak{g}$ which induces a decomposition of
$\frak{g}$ into one dimensional weight spaces, to be 2-step solvable. In
particular we show that the semidirect product of such a Lie algebra with its
torus of derivations cannot be itself 2-step solvable.

</DOC>
<DOC>
<DOCNO> 10181 </DOCNO>
Overcharging of a macroion by an oppositely charged polyelectrolyte


  The complexation of a polyelectrolyte with an oppositely charged spherical
macroion is studied for both salt free and salty solutions. When a
polyelectrolyte winds around the macroion, its turns repel each other and form
an almost equidistant coil. It is shown that this repulsive correlations of
turns lead to the charge inversion: more polyelectrolyte winds around the
macroion than it is necessary to neutralize it. The charge inversion becomes
stronger with increasing concentration of salt and can exceed 100%. This paper
confirms that correlations are the universal mechanism of charge inversion.

</DOC>
<DOC>
<DOCNO> 71040 </DOCNO>
Theoretical estimate(s) of the CP-violating quontity


  I give a short presentation of the theoretical prediction of
epsilon-prime/epsilon. Short distance and especially long distance aspects of
the computation is discussed. I consentrate on the general framework and the
chiral quark model approach, while other approaches are also shortly presented.
Because of the intrinsic uncertainties of the long-distance computations, it is
unlikely that new physics effects can be disentangled from the standard model
prediction.

</DOC>
<DOC>
<DOCNO> 122392 </DOCNO>
Weakly nonlinear theory of the Jeans instability in disk galaxies of


  The reaction of collective oscillations excited in the interaction between
aperiodically growing Jeans-type gravity perturbations and stars of a rapidly
rotating disk of flat galaxies is considered. An equation is derived which
describes the change in the main body of equilibrium distribution of stars in
the framework of the nonresonant weakly nonlinear theory. Certain applications
of the theory to the problem of relaxation of the Milky Way at radii where
two-body relaxation is not effective are explored. The theory, as applied to
the Solar neighborhood, accounts for observed features, such as the shape for
the velocity ellipsoid of stars and the increase in star random velocities with
age.

</DOC>
<DOC>
<DOCNO> 70825 </DOCNO>
Einstein and the Kaluza-Klein particle


  In his search for a unified field theory that could undercut quantum
mechanics, Einstein considered five dimensional classical Kaluza-Klein theory.
He studied this theory most intensively during the years 1938-1943. One of his
primary objectives was finding a non-singular particle solution. In the full
theory this search got frustrated and in the x^5-independent theory Einstein,
together with Pauli, argued it would be impossible to find these structures.

</DOC>
<DOC>
<DOCNO> 119201 </DOCNO>
Population synthesis of HII galaxies


  We study the stellar population of galaxies with active star formation,
determining ages of the stellar components by means of spectral population
synthesis of their absorption spectra. The data consist of optical spectra of
185 nearby ($z \leq 0.075$) emission line galaxies. They are mostly HII
galaxies, but we also include some Starbursts and Seyfert 2s, for comparison
purposes. They were grouped into 19 high signal-to-noise ratio template
spectra, according to their continuum distribution, absorption and emission
line characteristics. The templates were then synthesized with a star cluster
spectral base. The synthesis results indicate that HII galaxies are typically
age-composite stellar systems, presenting important contribution from
generations up to as old as 500 Myr. We detect a significant contribution of
populations with ages older than 1 Gyr in two groups of HII galaxies. The age
distributions of stellar populations among Starbursts can vary considerably
despite similarities in the emission line spectra. In the case of Seyfert 2
groups we obtain important contributions of old population, consistent with a
bulge. From the diversity of star formation histories, we conclude that typical
HII galaxies in the local universe are not systems presently forming their
first stellar generation.

</DOC>
<DOC>
<DOCNO> 118901 </DOCNO>
Discovery of High-Frequency QPOs in Black Hole Candidate XTE J1859+226


  We report the discovery of quasi-periodic oscillations (QPOs) at roughly 187
Hz and 150 Hz in the X-ray intensity of X-ray nova XTE J1859+226. The source
was observed during a recent outburst with RXTE. Besides these high-frequency
QPOs, we have also detected QPOs (and sometimes their harmonics) at 6--7 Hz,
and significant broad-band variability at low frequencies. These properties, as
well as the observed hard X-ray spectrum, make XTE J1859+226 a black hole
candidate (BHC).
  The detection of QPOs at two distinct frequencies $\gtrsim 100$ Hz in two
observations separated by about 4 hours provide additional insights into the
high-frequency QPO phenomenon in BHCs. The importance lies in the proposed
interpretations which invariably involve the effects of strong gravity near a
black hole. We compare our results to those of other BHCs, and discuss the
impact of the observational data on the models in a global context.

</DOC>
<DOC>
<DOCNO> 101929 </DOCNO>
Exponential Mixing of the 2D Stochastic Navier-Stokes Dynamics


  We consider the Navier-Stokes equation on a two dimensional torus with a
random force which is white noise in time, and excites only a finite number of
modes. The number of excited modes depends on the viscosity $\nu$, and grows
like $\nu^{-3}$ when $\nu$ goes to zero. We prove that this Markov process has
a unique invariant measure and is exponentially mixing in time.

</DOC>
<DOC>
<DOCNO> 7711 </DOCNO>
Decay on several sorts of heterogeneous centers: Special monodisperse


  The situation of the metastable phase decay on the several types of
heterogeneous centers is considered. This publication directly continues "
cond-mat@xxx.lanl.gov get 0001104 ", " cond-mat@xxx.lanl.gov get 0001108 ".
Here we present the numerical results for the floating monodisperse
approximation.

</DOC>
<DOC>
<DOCNO> 70334 </DOCNO>
Effective Majorana neutrino masses


  A generalisation of the neutrinoless double beta decay process is presented.
Neutrinoless double beta decay measures only one out of nine possible effective
Majorana neutrino masses in case of three flavours. Limits obtained for all the
matrix elements - some of them for the first time - are presented using data
from $\mu - e$ conversion, neutrino-nucleon scattering, HERA and rare kaon
decays. An outlook towards future possibilities to improve on the bounds is
given.

</DOC>
<DOC>
<DOCNO> 71199 </DOCNO>
Theoretical status of epsilon'/epsilon


  The Standard Model prediction for epsilon'/epsilon is updated, taking into
account the most recent theoretical developments. The final numerical value,
epsilon'/\epsilon = (17\pm 6) x 10^{-4}, is in good agreement with present
measurements.

</DOC>
<DOC>
<DOCNO> 100286 </DOCNO>
Factorization of generalized theta functions at reducible case


  We proved the factorization of generalized theta functions when the curve has
two irreducible components meeting at one node.

</DOC>
<DOC>
<DOCNO> 118981 </DOCNO>
Morphology-Density Relation for Simulated Clusters of Galaxies in Cold


  We present a model to investigate the formation and evolution of cluster
galaxies using cosmological N-body simulations. The N-body simulations are used
to make merging history trees of dark halos. Gas cooling, star formation,
supernova feedback and mergers of galaxies within dark halos are included by
using simple prescriptions taken from semi-analytic models of galaxy formation.
In this {\it Letter} we exam the merger-driven bulge formation model and
represent the morphology-density relation of cluster galaxies at z = 0. We find
that this morphological evolution model can explain the distribution of
elliptical galaxies in the clusters well and cannot reproduce the distribution
of S0 galaxies. This result suggests that the elliptical galaxies are mainly
formed by the major mergers, while, in the S0 formation, the processes other
than major mergers play important role.

</DOC>
<DOC>
<DOCNO> 117618 </DOCNO>
Glimpses of a strange star


  There are about 2000 gamma ray burst (GRB) events known to us with data
pouring in at the rate of one per day. While the afterglows of GRBs in radio,
optical and X-ray bands are successfully explained by the fireball model, a
significant difficulty with the proposed mechanisms for GRBs is that a small
amount ($\le 10^{-6} M_{\odot}$) of baryons in the ejecta can be involved.
There are very few models that fulfill this criteria together with other
observational features, among which are the differentially rotating collapsed
object model and the "supernova" model. These models generally invoke rapidly
rotating neutron stars, and may be subject to uncertainties in the formation
mechanisms and the equations of state of neutron stars. According to Spruit,
the problem of making a GRB from an X-ray binary is reduced to finding a
plausible way to make the star rotate differentially. We suggest that a model
of strange star (SS) can naturally explain many of these bursts with not only
their low baryon content, but the differential rotation which leads to an
enhanced magnetic field that surfaces up and is responsible for GRBs.

</DOC>
<DOC>
<DOCNO> 116383 </DOCNO>
Electron-drift driven ion-acoustic mode in a dusty plasma with


  Instabilities of ion-acoustic waves in a dusty plasma with electron-drift,
collisional, and dust charge fluctuations effects, have been investigated. The
regimes are clearly marked out where the theory is applicable. The critical
electron-drift velocity required to drive the instability is predicted. It is
also shown that electron thermal conductivity and charged grains concentration
enhance the growth of the ion-acoustic mode whereas ion-viscosity, ion-thermal
conductivity, and dust charge fluctuations have a stabilizing effect.

</DOC>
<DOC>
<DOCNO> 71916 </DOCNO>
Application of new multiloop QCD input to the analysis of $xF_3$ data


  The new theoretical input to the analysis of the experimental data of the
CCFR collaboration for $F_3$ structure function of $\nu N$ deep inelastic
scattering is considered. This input comes from the next-to-next-to-leading
order corrections to the anomalous dimensions of the Mellin moments of the
$F_3$ structure function. The QCD scale $\Lambda_{\overline{MS}}^{(4)}$ is
extracted from higher-twist independent fits. The results obtained demonstrate
the minimization of the influence of perturbative QCD contributions to the
value of $\Lambda_{\overline{MS}}^{(4)}$

</DOC>
<DOC>
<DOCNO> 150543 </DOCNO>
Intersecting Noncommutative D-branes and Baryons in Magnetic Fields


  We study supersymmetric intersecting configurations of D-branes with B-field
backgrounds. Noncommutative D-brane or M-brane pairs can intersect
supersymmetrically over (p-1)-brane, as well as over (p-2)-brane like ordinary
branes. d=10 and d=11 supergravity solutions are obtained and the supersymmetry
projection rule is examined. As an application we study a noncommutative
D7-brane probe in noncommutative D3-brane background, intersecting at
noncommutative plane, which describes BPS baryons of noncommutative gauge
theory in the context of AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 8234 </DOCNO>
Physics of polymer melts: A novel perspective


  We have mapped the physics of polymer melts onto a time-dependent
Landau-Ginzburg $|\psi|^4$ field theory using techniques of functional
integration. Time in the theory is simply a label for the location of a given
monomer along the extent of a flexible chain. With this model, one can show
that the limit of infinitesimal concentration of a polymer melt corresponds to
a {\em dynamic} critical phenomenon. The transition to the entangled state is
also shown to be a critical point. For larger concentrations, when the role of
fluctuations is reduced, a mean field approximation is justifiably employed to
show the existence of tube-like structures reminiscent of Edwards' model.

</DOC>
<DOC>
<DOCNO> 116481 </DOCNO>
Ermakov-Lewis angles for one-parameter supersymmetric families of


  We apply the Ermakov-Lewis procedure to the one-parameter damped modes
\tilde{y} recently introduced by Rosu and Reyes, which are related to the
common Newtonian free damping modes y by the general Riccati solution [H.C.
Rosu and M. Reyes, Phys. Rev. E 57, 4850 (1998), physics/9707019]. In
particular, we calculate and plot the angle quantities of this approach that
can help to distinguish these modes from the common y modes

</DOC>
<DOC>
<DOCNO> 116335 </DOCNO>
Phase transition in the ground state of a particle in a double-well


  We analyse the ground state of a particle in a double-well potential, with a
cylindrical symmetry, and in the presence of a magnetic field. We find that the
azimuthal quantum number m takes the values m = 0,1,2... when we increase the
magnetic field. At critical values of the magnetic field, the ground state is
twice degenerate. The magnetisation shows an oscillatory behaviour and jumps at
critical values of the magnetic field. This phase transition could be seen in
the condensate of a dilute gas of charged bosons confined by a double-well
potential.

</DOC>
<DOC>
<DOCNO> 151900 </DOCNO>
Poisson-Lie T-Duality in Supersymmetric WZNW Model


  The description of the two sets of (4,0) supersymmetric models that are
related by non-abelian duality transformations is given. The (4,0)
supersymmetric WZNW is constructed and the formulation of the (4,0)
supersymmetric sigma model dual to (4,0) supersymmetric WZNW model in the sense
of Poisson-Lie T-duality is described.

</DOC>
<DOC>
<DOCNO> 120942 </DOCNO>
Construction and Testing of a Pixellated CZT Detector and Shield for a


  We report on the construction and laboratory testing of pixellated CZT
detectors mounted in a flip-chip, tiled fashion and read out by an ASIC, as
required for proposed hard X-ray astronomy missions. Two 10 mm x 10 mm x 5 mm
detectors were fabricated, one out of standard eV Products high-pressure
Bridgman CZT and one out of IMARAD horizontal Bridgman CZT. Each was fashioned
with a 4 x 4 array of gold pixels on a 2.5 mm pitch with a surrounding guard
ring. The detectors were mounted side by side on a carrier card, such that the
pixel pitch was preserved, and read out by a 32-channel VA-TA ASIC from IDE AS
Corp. controlled by a PC/104 single-board computer. A passive shield/collimator
surrounded by plastic scintillator encloses the detectors on five sides and
provides a ~40deg field of view. Thus this experiment tests key techniques
required for future hard X-ray survey instruments. The experiment was taken to
Ft Sumner, NM in May 2000 in preparation for a scientific balloon flight aboard
the joint Harvard-MSFC EXITE2/HERO payload. Although we did not receive a
flight opportunity, and are currently scheduled to fly in September 2000, we
present our calibration data in the flight configuration together with data
analysis techniques and simulations of the expected flight background spectrum.

</DOC>
<DOC>
<DOCNO> 101280 </DOCNO>
The Lusztig cones of a quantized enveloping algebra of type A


  We show that for each reduced expression for the longest word in the Weyl
group of type A_n, the corresponding cone arising in Lusztig's description of
the canonical basis in terms of tight monomials is simplicial, and construct
explicit spanning vectors.

</DOC>
<DOC>
<DOCNO> 8179 </DOCNO>
A recurrent neural network with ever changing synapses


  A recurrent neural network with noisy input is studied analytically, on the
basis of a Discrete Time Master Equation. The latter is derived from a
biologically realizable learning rule for the weights of the connections. In a
numerical study it is found that the fixed points of the dynamics of the net
are time dependent, implying that the representation in the brain of a fixed
piece of information (e.g., a word to be recognized) is not fixed in time.

</DOC>
<DOC>
<DOCNO> 119867 </DOCNO>
FUSE Observations of the Active Cool Star AB Doradus


  Far ultraviolet spectra were obtained of the active cool star AB Doradus (HD
36705) during the calibration and checkout period of the FUSE satellite.
Observations in this early phase of the mission were taken at a resolving power
of 12000-15000 (~20-25 km/s) and covered the spectral range 905-1187 A. The
integrated spectrum exhibits strong, rotationally broadened stellar emission
from C III (977, 1175) and O VI (1032, 1037), and many weaker lines. Strong
emission lines of C III and O VI exhibit broad wings. The C III 977 profile
shows blue-shifted absorption at ~30 km/s and C II 1036 absorption appears
superposed on emission in the wing of O VI 1037. Rotational modulation of C III
and O VI is present, in harmony with its photometric variability. Flares were
detected in the brightest lines and subexposures were analyzed to examine flux
and profile variations. Downflows that extend to 600 km/s during a flare are
found in the O VI profiles. These early observations demonstrate that FUSE will
be an exceptional instrument for studying chromospheres in cool stars.

</DOC>
<DOC>
<DOCNO> 169998 </DOCNO>
Time Evolution of Quantum Fractals


  We propose a general construction of wave functions of arbitrary prescribed
fractal dimension, for a wide class of quantum problems, including the infinite
potential well, harmonic oscillator, linear potential and free particle. The
box-counting dimension of the probability density $P_t(x)=|\Psi(x,t)|^2$ is
shown not to change during the time evolution. We prove a universal relation
$D_t=1+D_x/2$ linking the dimensions of space cross-sections $D_x$ and time
cross-sections $D_t$ of the fractal quantum carpets.

</DOC>
<DOC>
<DOCNO> 151627 </DOCNO>
Distillation of vacuum entanglement to EPR pairs


  It is shown that by means of local interactions between a quantized
relativistic field and a pair of non-entangled atoms, entanglement can be
extracted from the vacuum and delivered to the atoms. The resulting mixed state
of the atoms can be further distilled to EPR pairs. Therefore, in principle,
teleportation and other entanglement assisted quantum communication tasks can
rely on the vacuum alone as a resource for entanglement.

</DOC>
<DOC>
<DOCNO> 178867 </DOCNO>
Barrier penetration and rotational damping of thermally excited


  We construct a microscopic model of thermally excited superdeformed states
that describes both the barrier penetration mechanism, leading to the decay-out
transitions to normal deformed states, and the rotational damping causing
fragmentation of rotational E2 transitions. We describe the barrier penetration
by means of a tunneling path in the two-dimensional deformation energy surface,
which is calculated with the cranked Nilsson-Strutinsky model. The individual
excited superdeformed states and associated E2 transition strengths are
calculated by the shell model diagonalization of the many-particle many-hole
excitations interacting with the delta-type residual two-body force. The effect
of the decay-out on the excited superdeformed states are discussed in detail
for $^{152}$Dy, $^{143}$Eu and $^{192}$Hg.

</DOC>
<DOC>
<DOCNO> 119840 </DOCNO>
Chandra X-ray Observatory Study of the Orion Nebula Cluster and BN/KL


  About 1000 X-ray emitting young pre-main sequence (PMS) stars distributed in
mass from 0.05 to 50 solar masses are detected in an image of the Orion Nebula
obtained with the Advanced CCD Imaging Spectrometer on board the Chandra X-ray
Observatory. This is the richest field of sources ever obtained in X-ray
astronomy. ACIS sources include 85-90% of V<20 stars, plus a substantial
fraction of deeply embedded stars with extinctions as high as A_V~60.
  The relationships between X-ray and other PMS stellar properties suggest that
X-ray luminosity of lower-mass PMS stars depends more on mass, and possibly
stellar rotation, than on bolometric luminosity as widely reported. A subsample
of unabsorbed solar-mass stars show high X-ray luminosities around L_x ~ 2 x
10^30 erg/s for the first ~2 My but diverge during 2-10 My with X-ray emission
plummeting in some stars but remaining high in others. This behavior is
consistent with theories of stellar rotational history and magnetic dynamos.
  The Becklin-Neugebauer/Kleinman-Low (BN/KL) region of massive star formation
shows both unabsorbed and embedded low-mass members of the Orion Nebula
Cluster, the luminous infrared Source n, and a class of sources without
photospheric counterparts that may be new magnetically active embedded PMS
stars. Several X-ray sources are also variable radio emitters. Faint X-ray
emission is seen close to, but apparently not coincident with the BN object.
Its nature is not clear.

</DOC>
<DOC>
<DOCNO> 102205 </DOCNO>
Vassiliev invariants and the cubical knot complex


  We construct a cubical CW-complex CK(M^3) whose rational cohomology algebra
contains Vassiliev invariants of knots in the 3-manifold M^3. We construct
\bar{CK}(R^3) by attaching cells to CK(R^3) for every degenerate 1-singular and
2-singular knot, and we show that \pi_1(\bar{CK}(R^3))=1 and
\pi_2(\bar{CK}(R^3))=Z. We give conditions for Vassiliev invariants to be
nontrivial in cohomology. In particular, for R^3 we show that v_2 uniquely
generates H^2(CK,D), where D is the subcomplex of degenerate singular knots.
More generally, we show that any Vassiliev invariant coming from the Conway
polynomial is nontrivial in cohomology. The cup product in H^*(CK) provides a
new graded commutative algebra of Vassiliev invariants evaluated on ordered
singular knots. We show how the cup product arises naturally from a
cocommutative differential graded Hopf algebra of ordered chord diagrams.

</DOC>
<DOC>
<DOCNO> 69212 </DOCNO>
The Strange Quark Mass From Flavor Breaking in Hadronic Tau Decays


  The strange quark mass is extracted from a finite energy sum rule (FESR)
analysis of the flavor-breaking difference of light-light and light-strange
quark vector-plus-axial-vector correlators, using spectral functions determined
from hadronic tau decay data. We point out problems for existing FESR
treatments associated with potentially slow convergence of the perturbative
series for the mass-dependent terms in the OPE over certain parts of the FESR
contour, and show how to construct alternate weight choices which not only cure
this problem, but also (1) considerably improve the convergence of the
integrated perturbative series, (2) strongly suppress contributions from the
region of s values where the errors on the strange current spectral function
are still large and (3) essentially completely remove uncertainties associated
with the subtraction of longitudinal contributions to the experimental decay
distributions. The result is an extraction of m_s with statistical errors
comparable to those associated with the current experimental uncertainties in
the determination of the CKM angle, V_{us}. We find m_s(1 GeV)=158.6\pm 18.7\pm
16.3\pm 13.3 MeV (where the first error is statistical, the second due to that
on V_{us}, and the third theoretical).

</DOC>
<DOC>
<DOCNO> 11706 </DOCNO>
Density of states for dirty d-wave superconductors: A unified and dual


  A two-parameter field theoretical representation is given of a 2-dimensional
dirty d-wave superconductor that interpolates between the Gaussian limit of
uncorrelated weak disorder and the unitary limit of a dilute concentration of
resonant scatterers. It is argued that a duality holds between these two
regimes from which follows that a linearly vanishing density of states in the
Gaussian limit transforms into a diverging one in the unitary limit arbitrarily
close to the Fermi energy.

</DOC>
<DOC>
<DOCNO> 121290 </DOCNO>
Chandra Observations of Cygnus A: Magnetic Field Strengths in the Hot


  We report X-ray observations of the powerful radio galaxy Cygnus A with the
Chandra X-ray Observatory. This letter focuses on the radio hot spots, all four
of which are detected in X-rays with a very similar morphology to their radio
structure. X-ray spectra have been obtained for the two brighter hot spots (A
and D). Both are well described by a power law with photon index \Gamma = 1.8
\pm 0.2 absorbed by the Galactic column in the direction of Cygnus A. Thermal
X-ray models require too high gas densities and may be ruled out. The images
and spectra strongly support synchrotron self-Compton models of the X-ray
emission, as proposed by Harris, Carilli & Perley on the basis of ROSAT imaging
observations. Such models indicate that the magnetic field in each of the
brighter hot spots is 1.5 \times 10^-4 gauss, with an uncertainty of a few tens
of percent. This value is close to the equipartition field strengths assuming
no protons are present. The possibility that the X-rays are synchrotron
radiation is briefly discussed, but not favored. We speculate that production
of the \gamma \sim 10^7 electrons necessary for X-ray synchrotron radiation
from hot spots is inhibited when the external gas density is high, as is the
case when the radio galaxy is within a cooling flow.

</DOC>
<DOC>
<DOCNO> 10068 </DOCNO>
Generalized Entropy approach to far-from-equilibrium statistical


  We present a new approach to far-from-equilibrium statistical mechanics,
based on the concept of generalized entropy, which is a microscopically-defined
generalization of Onsager-Machlup functional. In the case when a set of slow
(adiabatic) variables can be chosen, our formalism yields a general form of the
macroscopic evolution law (Generalized Langevin Equation) and extends
Fluctuation Dissipative Theorem. It also provides for a simple understanding of
recently-discovered Fluctuation Theorem

</DOC>
<DOC>
<DOCNO> 170497 </DOCNO>
Quantum Information Theory


  In this thesis I present a short review of ideas in quantum information
theory. The first chapter contains introductory material, sketching the central
ideas of probability and information theory. Quantum mechanics is presented at
the level of advanced undergraduate knowledge, together with some useful tools
for quantum mechanics of open systems. In the second chapter I outline how
classical information is represented in quantum systems and what this means for
agents trying to extract information from these systems. The final chapter
presents a new resource: quantum information. This resource has some
bewildering applications which have been discovered in the last ten years, and
continually presents us with unexpected insights into quantum theory and the
universe.
  The treatment is pedagogical and suitable for beginning graduates in the
field.

</DOC>
<DOC>
<DOCNO> 9990 </DOCNO>
Exact Solution of the Infinite-Range Quantum Mattis Model


  We have solved the quantum version of the Mattis model with infinite-range
interactions. A variational approach gives the exact solution for the
infinite-range system, in spite of the non-commutative nature of the quantum
spin components; this implies that quantum effects are not predominant in
determining the macroscopic properties of the system. Nevertheless, the model
has a surprisingly rich phase behaviour, exhibiting phase diagrams with
tricritical, three-phase and critical end points.

</DOC>
<DOC>
<DOCNO> 122496 </DOCNO>
Constraints from the Lyman alpha forest power spectrum


  We use published measurements of the transmission power spectrum of the Lyman
alpha forest to constrain several parameters that describe cosmology and
thermal properties of the intergalactic medium (IGM). A 6 parameter grid is
constructed using Particle-Mesh dark matter simulations together with scaling
relations to make predictions for the gas properties. We fit for all parameters
simultaneously and identify several degeneracies. We find that the temperature
of the IGM can be well determined from the fall-off of the power spectrum at
small scales. We find a temperature around 20.000 K, dependent on the slope of
the gas equation of state. We see no evidence for evolution in the IGM
temperature. We place constraints on the amplitude of the dark matter
fluctuations. However, contrary to previous results, the slope of the dark
matter power spectrum is poorly constrained. This is due to uncertainty in the
effective Jeans smoothing scale, which depends on the temperature as well as
the thermal history of the gas.

</DOC>
<DOC>
<DOCNO> 10942 </DOCNO>
Green function of fermions in 2D superconducting Frohlich model with


  The fermion Green function and spectral characteristics for the 2D Frohlich
model of superconductivity at static fluctuations in the phase of the order
parameter are calculated. The results demonstrate strongly non-Fermi-liquid
properties of the system at finite temperatures and relate with the pseudogap
behavior of high-$T_{c}$ superconductors at relatively small charge carrier
densities.

</DOC>
<DOC>
<DOCNO> 84206 </DOCNO>
BTZ Black Hole Entropy in Higher Curvature Gravity


  For the BTZ black hole in the Einstein gravity, a statistical entropy has
been calculated. It is equal to the Bekenstein-Hawking entropy. In this
article, its statistical entropy in the higer curvature gravity is calculated
and shown to be equal to one derived by using the Noether charge method. This
suggests that the equivalence between the geometrical and statistical entropies
of the black hole is retained in the general diffeomorphism invariant theories
of gravity. A relation between the cosmic censorship conjecture and the
unitarity of the conformal field theory on the boundary of AdS_3 is also
discussed.

</DOC>
<DOC>
<DOCNO> 102907 </DOCNO>
Extended F_4-buildings and the Baby Monster


  The Baby Monster group B acts naturally on a geometry E(B) with diagram
c.F_4(t) for t=4 and the action of B on E(B) is flag-transitive. It possesses
the following properties:
   (a) any two elements of type 1 are incident to at most one common element of
type 2, and
   (b) three elements of type 1 are pairwise incident to common elements of
type 2 iff they are incident to a common element of type 5.
  It is shown that E(B) is the only (non-necessary flag-transitive)
c.F_4(t)-geometry, satisfying t=4, (a) and (b), thus obtaining the first
characterization of B in terms of an incidence geometry, similar in vein to one
known for classical groups acting on buildings. Further, it is shown that E(B)
contains subgeometries E(^2E_6(2)) and E(Fi22) with diagrams c.F_4(2) and
c.F_4(1). The stabilizers of these subgeometries induce on them flag-transitive
actions of ^2E_6(2):2 and Fi22:2, respectively. Three further examples for t=2
with flag-transitive automorphism groups are constructed. A complete list of
possibilities for the isomorphism type of the subgraph induced by the common
neighbours of a pair of vertices at distance 2 in an arbitrary c.F_4(t)
satisfying (a) and (b) is obtained.

</DOC>
<DOC>
<DOCNO> 121025 </DOCNO>
Sensitivity of the Radial Velocity Technique in Detecting Outer Planets


  The technique of radial velocity (RV) has produced spectacular discoveries of
short-period Jovian mass objects around a fraction (5 to 10%) of nearby G
stars. Although we expect Jovian planets to be located in long-period orbits of
decades or longer (if our solar system is any guide), detecting such planets
with RV technique is difficult due to smaller velocity amplitudes and the
limited temporal baseline (5-10 yr) of current searches relative to the
expected orbital periods. In this paper, we develop an analytical understanding
of the sensitivity of RV technique in the regime where the the orbital period
is larger than the total baseline of the survey. Moreover, we focus on the
importance of the orbital phase in this ``long-period'' regime, and develop a
Least Squares detection technique based on the amplitude and phase of the
fitted signal.
  To illustrate the benefits of this amplitude-phase analysis, we compare it to
existing techniques. Previous authors (e.g. Nelson & Angel 1998) have explored
the sensitivity of an amplitude-only analysis using Monte Carlo simulations.
Others have supplemented this by using the slope of the linear component of the
fitted sinusoid in addition (e.g. Walker et al. 1995; Cumming et al. 1999). In
this paper, we illustrate the benefits of Least Squares over periodogram
analysis, and demonstrate the superiority of an amplitude-phase technique over
previous analyses.

</DOC>
<DOC>
<DOCNO> 101863 </DOCNO>
Heat kernel asymptotics for Laplace type operators and matrix KdV


  We study the heat kernel asymptotics for the Laplace type differential
operators on vector bundles over Riemannian manifolds. In particular this
includes the case of the Laplacians acting on differential p-forms. We extend
our results obtained earlier for the scalar Laplacian and present closed
formulas for all heat invariants associated with these operators. As another
application, we present new explicit formulas for the matrix Korteweg-de Vries
hierarchy.

</DOC>
<DOC>
<DOCNO> 121573 </DOCNO>
Atmospheric Secondary Particles In Near Earth Space


  The Alpha Magnetic Spectrometer detects a large amount of particles below
rigidity cutoff. Those high energy particles create questions related to
radiation belts and atmospheric neutrinos. To understand the origin of these
particles, we use a trajectory tracing program to simulate particle
trajectories in realistic geomagnetic field. The complex behaviors and large
e^+/e^- are explained here.

</DOC>
<DOC>
<DOCNO> 100040 </DOCNO>
A simple question about a complicated object


  Let n and k be positive integers with and k < n.
  Then of course SU(k,1) is contained into SU(n,1).
  Moreover, which is less clear - but proved by Khoroshkin -, the
representation theory of SU(k,1) at the generalized infinitesimal character of
the trivial module can be fully (and even Ext-fully) embedded into that of
SU(n,1). Here is the obvious bet: This embedding is implemented by the
cohomological induction functor. I conjecture that a similar phenomenon occurs
whenever SU(k,1) is a Levi factor of a theta stable parabolic subalgebra of a
reductive group.

</DOC>
<DOC>
<DOCNO> 116985 </DOCNO>
Simulation Studies of the NLC with Improved Ground Motion Models


  The performance of various systems of the Next Linear Collider (NLC) have
been studied in terms of ground motion using recently developed models. In
particular, the performance of the beam delivery system is discussed. Plans to
evaluate the operation of the main linac beam-based alignment and feedback
systems are also outlined.

</DOC>
<DOC>
<DOCNO> 170224 </DOCNO>
Exact solutions for a family of discretely spiked harmonic oscillators


  Factorization method is developed for a family of discretely spiked harmonic
oscillators. Two sets of intertwining and ladder operators are presented to
algebraically generate eigenstates with energies isomorphic to those of the
ordinary harmonic oscillator. Normalization conditions are examined to reject
unphysical cases. Generic theory is specialized to one dimensional linear
oscillator and N dimensional radial oscillators in odd dimensions N=1,3,5..,
where orthogonal basis or sets of staggered orthogonal bases can be identified.
Even dimensions N=2,4,6.. are rejected as ill defined since they do not lead to
properly defined bases. The theory is augmented by a short Haskell program
Spike, which directly implements the intertwining and ladder operators,
generates the eigenfunctions, tests integrability of the solutions, verifies
orthogonality conditions and tests consistency of theoretical claims.

</DOC>
<DOC>
<DOCNO> 99616 </DOCNO>
Modern Mathematical Physics: what it should be?


  Personal view of author on goals and content of Mathematical Physics.

</DOC>
<DOC>
<DOCNO> 122580 </DOCNO>
Baryon-poor outflows from rotating black holes


  Cosmological gamma-ray bursts are probably powered by systems harboring a
rotating black hole. We show that frame-dragging creates baryon-poor outflows
in a differentially rotating gap along an open magnetic flux-tube with
dissipation $P=\Omega_T(\Omega_H-2\Omega_T)A_\phi^2$, where $2\pi A_\phi$
denotes the flux in the open tube, for angular velocities $\Omega_H$ and
$\Omega_T$ of the black hole and the torus, respectively. The output in
photon-pair outflow will be reprocessed in an intervening hypernova progenitor
wind or the ISM.

</DOC>
<DOC>
<DOCNO> 39794 </DOCNO>
MSW Effects in Vacuum Oscillations


  We point out that for solar neutrino oscillations with the mass-squared
difference of Delta m^2 ~ 10^-10 - 10^-9 eV^2, traditionally known as ``vacuum
oscillation'' range, the solar matter effects are non-negligible, particularly
for the low energy pp neutrinos. One consequence of this is that the values of
the mixing angle theta and pi/2-theta are not equivalent, leading to the need
to consider the entire physical range of the mixing angle 0<=theta<=pi/2 when
determining the allowed values of the neutrino oscillation parameters.

</DOC>
<DOC>
<DOCNO> 100872 </DOCNO>
Limits of Finite Dimensional Nest Algebras


  We introduce order conserving embeddings as a more general form of order
preserving embeddings between finite dimensional nest algebras. The structure
of these embeddings is determined, in terms of order indecomposable
decompositions, and they are shown to be determined up to inner conjugacy by
their induced maps on $K_0$. Classifications of direct systems and limit
algebras are obtained in terms of dimension distribution groups.

</DOC>
<DOC>
<DOCNO> 8432 </DOCNO>
Soft Phonon Anomalies in the Relaxor Ferroelectric


  Neutron inelastic scattering measurements of the polar TO phonon mode
dispersion in the cubic relaxor Pb(Zn_1/3Nb_2/3)_0.92Ti_0.08O_3 at 500K reveal
anomalous behavior in which the optic branch appears to drop precipitously into
the acoustic branch at a finite value of the momentum transfer q=0.2 inverse
Angstroms, measured from the zone center. We speculate this behavior is the
result of nanometer-sized polar regions in the crystal.

</DOC>
<DOC>
<DOCNO> 122188 </DOCNO>
An Approximate Determination of the Gas-Phase Metal Abundance in


  (modified for brevity) It is important to determine whether the observed bow
shocks in the working surfaces of Herbig-Haro outflows has lead to a
destruction of dust grains and consequently to a change in the gas phase metal
abundances (say of Fe) in the cooling regions of HH bow shocks. Detailed
studies are currently available for only 5 HH outflows (Beck-Winchatz et al.\
1996), due to the large observational and theoretical effort required to
determine metal abundances in HH objects.
        Information about metal abundances in more HH objects is badly needed.
We therefore use a very approximate method by introducing a "characteristic
number", A_me, whose definition is based only on often observed line fluxes. We
find a good correlation between A_me and the Fe abundance for the 5
well-studied HH objects. We use this correlation to determine approximate
values of the gas phase Fe abundance in 13 additional high excitation and in 3
additional low excitation HH objects.
        Of the 16 high excitation HH objects studied, there are 6 which
approximately agree with normal population I abundance (i.e., no depletion due
to dust formation). The remaining 10 show some Fe gas phase depletion which
never gets larger than by a factor of 2.5. This result is in agreement with our
qualitative expectations that fast shocks efficiently destroy dust grains. Of
the 5 low excitation HH objects studied, there are 4 which, unexpectedly, show
a normal population I abundance. In low excitation objects, one might expect
strong gas phase Fe depletion (showing the unchanged molecular cloud
composition), unless the matter has previously gone through shocks of much
higher shock velocities.

</DOC>
<DOC>
<DOCNO> 123080 </DOCNO>
Near-Infrared Spectral Classification of late-M and L Dwarfs


  We present near-infrared (1 to 2.5 micron) low-resolution spectroscopy of
eleven ultracool dwarfs with spectral types ranging from M7 to L8. Combining
our observations with data published previously by Leggett et al. (2001), we
have measured equivalent widths for the strongest atomic features and
constructed narrowband indices to gauge the strength of the strongest molecular
features. Those measurements show that the behaviourr at near-infrared
wavelengths is well correlated with spectral type, where the latter is defined
from observations between 6300 and 10000 Angstroms. In particular, four indices
designed to measure absorption in the wings of the 1.4 and 1.85 micron steam
bands exhibit a linear, monotonic correlation with spectral type on the
Kirkpatrick et al. (1999) system, allowing consistent calibration from both
optical and near-infrared spectroscopy.

</DOC>
<DOC>
<DOCNO> 12522 </DOCNO>
Statistical Mechanics of Low-Density Parity Check Error-Correcting Codes


  A variation of low density parity check (LDPC) error correcting codes defined
over Galois fields ($GF(q)$) is investigated using statistical physics. A code
of this type is characterised by a sparse random parity check matrix composed
of $C$ nonzero elements per column. We examine the dependence of the code
performance on the value of $q$, for finite and infinite $C$ values, both in
terms of the thermodynamical transition point and the practical decoding phase
characterised by the existence of a unique (ferromagnetic) solution. We find
different $q$-dependencies in the cases of C=2 and $C \ge 3$; the analytical
solutions are in agreement with simulation results, providing a quantitative
measure to the improvement in performance obtained using non-binary alphabets.

</DOC>
<DOC>
<DOCNO> 12352 </DOCNO>
The random field critical concentration in dilute antiferromagnets


  Monte Carlo techniques are used to investigate the equilibrium threshold
concentration, xe, in the dilute anisotropic antiferromagnet Fe(x)Zn(1-x)F2 in
an applied magnetic field, considered to be an ideal random-field Ising model
system. Above xe equilibrium behavior is observed whereas below xe
metastability and domain formation dominate. Monte Carlo results agree very
well with experimental data obtained using this system.

</DOC>
<DOC>
<DOCNO> 117364 </DOCNO>
Antikaon condensation in neutron stars


  We investigate the condensation of charged $K^-$ meson and neutral $\bar K^0$
meson in dense neutron star matter. Calculations are performed in relativistic
mean field models in which both the baryon-baryon and (anti)kaon-baryon
interactions are mediated by meson exchange. It is found that $\bar K^0$
condensation is quite sensitive to the antikaon optical potential and depends
more strongly on the nucleonic equation of state. For moderate values of
antikaon potential and a rather stiff equation of state, a significant region
of maximum mass star will contain $\bar K^0$ meson. The critical density of
$\bar K^0$ condensation is always higher than that of $K^-$ condensation. With
the appearance of $K^-$ and $\bar K^0$ condensates, pairs of $p-K^-$ and
$n-\bar K^0$ are produced with equal proportion leading to a perfectly
symmetric matter of nucleons and antikaons in neutron stars. Along with $K^-$
condensate, $\bar K^0$ condensate makes the equation of state much softer
resulting in smaller maximum mass stars compared to the case without any
condensate.

</DOC>
<DOC>
<DOCNO> 40530 </DOCNO>
Measurement of the $\Lambda_{c}^{+}$ Lifetime


  The $\Lambda_{c}^{+}$ lifetime is measured using 9.0 fb$^{-1}$ of $e^+e^-$
annihilation data collected on or just below the $\Upsilon(4S)$ resonance with
the CLEO II.V detector at CESR. Using an unbinned maximum likelihood fit, the
$\Lambda_{c}^{+}$ lifetime is measured to be $(179.6 \pm 6.9(stat.) \pm
4.4(syst.))$ fs. The precision of this colliding beam measurement is comparable
to other measurements, which are based on fixed target experiments with
different systematic errors.

</DOC>
<DOC>
<DOCNO> 150589 </DOCNO>
Finite energy/action solutions of $p_1$ Yang-Mills equations on $p_2$


  Physically relevant gauge and gravitational theories can be seen as special
members of hierarchies of more elaborate systems. The Yang-Mills (YM) system is
the first member of a hierarchy of Lagrangians which we will index by $p_1$,
and the Einstein-Hilbert (EH) system of general relativity is the first member
of another hierarchy which we index by $p_2$. In this paper, we study the
classical equations of the $p_1 = 1,2$ YM hierarchy considered in the
background of special geometries (Schwarzschild, deSitter,anti-deSitter) of the
$p_2=1,2,3$ EH hierarchy. Solutions are obtained in various dimensions and lead
to several examples of non-self-dual YM fields. When $p_1=p_2$ self-dual
solutions exist in addition. Their action is equal to the Chern-Pontryagin
charge and can be compared with that of the non-self-dual solutions.

</DOC>
<DOC>
<DOCNO> 9326 </DOCNO>
Modified BCS mechanism of Cooper pair formation in narrow energy bands


  The superconductor niobium possesses a narrow, roughly half-filled energy
band with Bloch functions which can be unitarily transformed into optimally
localized spin-dependent Wannier functions belonging to a double-valued
representation of the space group of Nb. The special symmetry of this
"superconducting band" can be interpreted within a nonadiabatic extension of
the Heisenberg model of magnetism. While the original Heisenberg model assumes
that there is exactly one electron at each atom, the nonadiabatic model
postulates that the Coulomb repulsion energy in narrow, partly filled energy
bands is minimum when the balance between the bandlike and atomiclike behavior
is shifted as far as possible towards the atomiclike behavior. Within this
nonadiabatic Heisenberg model, the electrons of the superconducting band form
Cooper pairs at zero temperature. Just as in the BCS theory of superconduc-
tivity, this formation of Cooper pairs is mediated by phonons. However, there
is an important difference: within the nonadiabatic Heisenberg model, the
electrons in a narrow superconducting band are constrained to form Cooper pairs
because the conservation of spin angular momentum would be violated in any
normal conducting state. There is great evidence that these constraining forces
are responsible for superconducting eigenstates. That means that an attractive
electron-electron interaction alone is not able to produce stable Cooper pairs.
In addition, the constraining forces established within the nonadiabatic
Heisenberg model must exist in a superconductor.

</DOC>
<DOC>
<DOCNO> 70899 </DOCNO>
Color Dynamics In Phase Space: The Balescu-Lenard-Vlasov Approach


  We propose to use the Balescu-Lenard-Vlasov (BLV) equation to describe
relativistic heavy ion collisions. We use an inter-quark Richardson's potential
consistent with the indications of Lattice QCD calculations. The color degrees
of freedom are explicitly taken into account.
 We explicitly demonstrate that the Vlasov approach alone is insufficient in
the hadronization region.
 In order to overcome this problem we prepare the initial condition for many
events using molecular dynamics with frictional cooling and a Thomas-Fermi
approximation to the Fermi motion.
  These events are averaged and propagated in time using the Vlasov approach.
The fluctuations are used to evaluate the collision term and in turn the number
of q-$\bar q$ created.

</DOC>
<DOC>
<DOCNO> 68308 </DOCNO>
Scaling and Duality in Semi-exclusive Processes


  We discuss extending scaling and duality studies to semi-exclusive processes.
We show that semi-exclusive hard pion photoproduction should exhibit scaling
behavior in kinematic regions where the photon and pion both interact directly
with the same quark. We show that such kinematic regions exist. We also show
that the constancy with changing momentum transfer of the resonance
peak/scaling curve ratio, familiar for many resonances in deep inelastic
scattering, is also expected in the semi-exclusive case.

</DOC>
<DOC>
<DOCNO> 7773 </DOCNO>
Fluctuations and correlations in population models with age structure


  We study the population profile in a simple discrete time model of population
dynamics. Our model, which is closely related to certain ``bit-string'' models
of evolution, incorporates competition for resources via a population dependent
death probability, as well as a variable reproduction probability for each
individual as a function of age. We first solve for the steady-state of the
model in mean field theory, before developing analytic techniques to compute
Gaussian fluctuation corrections around the mean field fixed point. Our
computations are found to be in good agreement with Monte-Carlo simulations.
Finally we discuss how similar methods may be applied to fluctuations in
continuous time population models.

</DOC>
<DOC>
<DOCNO> 84409 </DOCNO>
Relativistic Effects in the Motion of the Moon


  The main general relativistic effects in the motion of the Moon are briefly
reviewed. The possibility of detection of the solar gravitomagnetic
contributions to the mean motions of the lunar node and perigee is discussed.

</DOC>
<DOC>
<DOCNO> 117640 </DOCNO>
Oxygen Absorption in Cooling Flows


  The inhomogeneous cooling flow scenario predicts the existence of large
quantities of gas in massive elliptical galaxies, groups, and clusters that
have cooled and dropped out of the flow. Using spatially resolved, deprojected
X-ray spectra from the ROSAT PSPC we have detected strong absorption over
energies ~0.4-0.8 keV intrinsic to the central ~1 arcmin of the galaxy, NGC
1399, the group, NGC 5044, and the cluster, A1795. These systems have amongst
the largest nearby cooling flows in their respective classes and low Galactic
columns. Since no excess absorption is indicated for energies below ~0.4 keV
the most reasonable model for the absorber is warm, collisionally ionized gas
with T=10^{5-6} K where ionized states of oxygen provide most of the
absorption. Attributing the absorption only to ionized gas reconciles the large
columns of cold H and He inferred from Einstein and ASCA with the lack of such
columns inferred from ROSAT, and also is consistent with the negligible atomic
and molecular H inferred from HI, and CO observations of cooling flows. The
prediction of warm ionized gas as the product of mass drop-out in these and
other cooling flows can be verified by Chandra, XMM, and ASTRO-E.

</DOC>
<DOC>
<DOCNO> 119348 </DOCNO>
Detection of Strong Clustering of Extremely Red Objects: Implications


  We present the results of a wide-field survey for extremely red objects (EROs
hereafter), the widest so far, based on Ks and R band imaging. The survey
covers 701 arcmin^2 and it is 85% complete to Ks\leq18.8 over the whole area
and to Ks\leq19.2 over 447.5 arcmin^2. Thanks to the wide field covered, a
complete sample of about 400 EROs with R-Ks\geq5 was selected. The distribution
of the EROs on the sky is strongly inhomogeneous, being characterized by
overdensities and large voids. We detect at the 8 sigma level a strong
clustering signal of the EROs which is about an order of magnitude larger than
the clustering of K-selected field galaxies in the same magnitude range. A
smooth trend of increasing clustering amplitude with the R-Ks color is
observed. These results are strong evidence that the largest fraction of EROs
is composed of high-z ellipticals, of which we detect for the first time the
z\simgt1 large scale structure clustering signal. We show how the surface
density variations of the ERO population found in our survey can explain the
highly discrepant results obtained so far on the density of z > 1 ellipticals,
and we briefly discuss the main implications of our results for the evolution
of elliptical galaxies. The number counts and the colors of the K-selected
field galaxies are also presented and briefly discussed.

</DOC>
<DOC>
<DOCNO> 150807 </DOCNO>
Boundary Logarithmic Conformal Field Theory


  We discuss the effect of boundaries in boundary logarithmic conformal field
theory and show, with reference to both $c=-2$ and $c=0$ models, how they
produce new features even in bulk correlation functions which are not present
in the corresponding models without boundaries. We discuss the modification of
Cardy's relation between boundary states and bulk quantities.

</DOC>
<DOC>
<DOCNO> 8625 </DOCNO>
Tomonaga-Luttinger features in the resonant Raman spectra of quantum


  The differential cross section for resonant Raman scattering from the
collective modes in a one dimensional system of interacting electrons is
calculated non-perturbatively using the bosonization method. The results
indicate that resonant Raman spectroscopy is a powerful tool for studying
Tomonaga-Luttinger liquid behaviour in quasi-one dimensional electron systems.

</DOC>
<DOC>
<DOCNO> 84546 </DOCNO>
Wormholes in Simplicial Minisuperspace


  Using simplicial minisuperspace techniques we obtain a wormhole
configuration, capable of modelling both a throat between two equal Euclidean
and Lorentzian universes. Computing the wavefunction associated to such
configuration we conclude that for Planck-size Euclidean wormholes there is a
prediction of a finite non-vanishing radius of their throat, even in the
absence of matter. The wavefunction associated to their Lorentzian counterparts
predicts the growth of the wormhole's throat as the two Lorentzian universes
expand.

</DOC>
<DOC>
<DOCNO> 118938 </DOCNO>
Large scale magnetic fields and their dissipation in GRB fireballs


  We consider possible geometries of magnetic fields in GRB outflows, and their
evolution with distance from the source. For magnetically driven outflows, with
an assumed ratio of magnetic to kinetic energy density of order unity, the
field strengths are sufficient for efficient production of gamma-rays by
synchrotron emission in the standard internal shock scenario, without the need
for local generation of small scale fields. In these conditions, the MHD
approximation is valid to large distances (>10^19cm). In outflows driven by
nonaxisymmetric magnetic fields, changes of direction of the field cause
dissipation of magnetic energy by reconnection. This dissipation takes place
outside the photosphere of the outflow, and can convert a significant fraction
of the magnetic energy flux into radiation.

</DOC>
<DOC>
<DOCNO> 7616 </DOCNO>
Extinction transition in bacterial colonies under forced convection


  We report the spatio-temporal response of {\it Bacillus subtilis} growing on
a nutrient-rich layer of agar to ultra-violet (UV) radiation. Below a crossover
temperature, the bacteria are confined to regions that are shielded from UV
radiation. A forced convection of the population is effected by rotating a UV
radiation shield relative to the petri dish. The extinction speed at which the
bacterial colony lags behind the shield is found to be qualitatively similar to
the front velocity of the colony growing in the absence of the hostile
environment as predicted by the model of Dahmen, Nelson and Shnerb. A
quantitative comparison is not possible without considering the slow dynamics
and the time-dependent interaction of the population with the hostile
environment.

</DOC>
<DOC>
<DOCNO> 121450 </DOCNO>
The beryllium abundance in the very metal-poor halo star G 64-12 from


  We report on a new spectroscopic analysis of the very metal deficient star G
64-12 ([Fe/H]=-3.3), aimed at determining, for the first time, its Be content.
The spectra were observed during the Science Verification of UVES, the ESO VLT
Ultraviolet and Visible Echelle Spectrograph. The high resolution (~48,000) and
high S/N (~130 per pixel) achieved at the wavelengths of the BeII resonance
doublet allowed an accurate determination of its abundance: log N(Be/H) =
-13.10 +/- 0.15 dex. The Be abundance is significantly higher than expected
from previous measurements of Be in stars of similar metallicity (3D and NLTE
corrections acting to make a slightly higher value than an LTE analysis). When
compared to iron, the high [Be/Fe] ratio thus found may suggest a flattening in
the beryllium evolutionary trend at the lowest metallicity end or the presence
of dispersion at early epochs of galactic evolution.

</DOC>
<DOC>
<DOCNO> 68543 </DOCNO>
RG Flow, Wilson Loops and the Dilaton Tadpole


  We discuss the role of the dilaton tadpole in the holographic description of
non-supersymmetric gauge theories that are conformal in the planar limit. On
the string theory side, the presence of the dilaton tadpole modifies the AdS
background inducing a logarithmic running for the radius and the dilaton. Using
the holographic prescription we compute the Wilson loop on the gravity side and
find a smooth interpolating potential between asymptotic freedom and
confinement, as expected from field theory.

</DOC>
<DOC>
<DOCNO> 71266 </DOCNO>
Inverted Hierarchy of Neutrino Masses Disfavored by Supernova 1987A


  We discuss the flavor conversion of supernova neutrinos in the three-flavor
mixing scheme of neutrinos. We point out that by neutrino observation from
supernova one can discriminate the inverted hierarchy of neutrino masses from
the normal one if s_{13}^2 \gsim a few \times 10^{-4}, irrespective of which
oscillation solution to the solar neutrino problem is realized in nature. We
perform an analysis of data of SN1987A and obtain a strong indication that the
inverted mass hierarchy is disfavored unless s_{13}^2 \lsim a few \times
10^{-4}.

</DOC>
<DOC>
<DOCNO> 102072 </DOCNO>
Recent Progress in Algebraic Combinatorics


  A survey of recent progress in three areas of algebraic combinatorics: (1)
the Saturation Conjecture for Littlewood-Richardson coefficients, (2) the n!
and (n+1)^{n-1} conjectures, and (3) longest increasing subsequences of
permutations.

</DOC>
<DOC>
<DOCNO> 101517 </DOCNO>
Topological quantum field theory and four-manifolds


  I review some recent results on four-manifold invariants which have been
obtained in the context of topological quantum field theory. I focus on three
different aspects: (a) the computation of correlation functions, which give
explicit results for the Donaldson invariants of non-simply connected
manifolds, and for generalizations of these invariants to the gauge group
SU(N); (b) compactifications to lower dimensions, and relations with
three-manifold topology and with intersection theory on the moduli space of
flat connections on Riemann surfaces; (c) four-dimensional theories with
critical behavior, which give some remarkable constraints on Seiberg-Witten
invariants and new results on the geography of four-manifolds.

</DOC>
<DOC>
<DOCNO> 70363 </DOCNO>
Bottom Quark Mass from Upsilon Mesons: Charm Mass Effects


  The effects of the finite charm quark mass on bottom quark mass
determinations from $\Upsilon$ sum rules are examined in detail. The charm
quark mass effects are calculated at next-to-next-to-leading order in the
non-relativistic power counting for the $\Upsilon$ sum rules and at order
$\alpha_s^3$ for the determination of the bottom MSbar mass. For the bottom 1S
mass, which is extracted from the $\Upsilon$ sum rules directly, we obtain
$M_b^{1S}=4.69\pm 0.03$ GeV with negligible correlation to the value of the
strong coupling. For the bottom MSbar mass we obtain $\bar M_b(\bar M_b) =
4.17\pm 0.05$ GeV taking $\alpha_s^{(n_l=5)}(M_Z)=0.118\pm 0.003$ as an input.
Compared with an analysis where all quarks lighter than the bottom are treated
as massless, we find that the finite charm mass shifts the bottom 1S mass,
$M_b^{1S}$, by about -20 MeV and the MSbar mass, $\bar M_b(\bar M_b)$, by -30
to -35 MeV.

</DOC>
<DOC>
<DOCNO> 10027 </DOCNO>
Geometrical Approach for the Mean-Field Dynamics of a Particle in a


  The zero temperature relaxational dynamics of a particle in a short range
correlated random potential is addressed. We derive a set of "two-times"
mean-field dynamical equations, accounting for a possible mean displacement of
the particle when subject to an external force. We show first detailed results
from the numerical integration of the above mentionned equations. We mainly pay
attention to the exponentially decreasing spatial correlations case, for which
simple analytical arguments provide valuable results about the hessian of the
energy landscape, and we propose a geometrical description of the "mean-field
aging". Our numerical results and further analytical arguments give access to
the waiting time dependence of the main characteristic time scales.

</DOC>
<DOC>
<DOCNO> 123066 </DOCNO>
The "Number - Flux Density" Relation for Milliarcsecond Structures in


  ``Number - flux density'' distributions for total and correlated flux
densities at various interferometer spacings in 355 extragalactic radio sources
are analysed. Qualitative conclusions on the population of milliarcsecond
components in these sources are presented.

</DOC>
<DOC>
<DOCNO> 71465 </DOCNO>
Supersymmetry predictions for epsilon'/epsilon


  We study the predictions for the direct CP violation parameter
epsilon'/epsilon in a class of string-inspired model with non-universal soft
A-terms. We show that the non-universality of the A-terms plays an important
rule in enhancing the supersymmetric contributions to the CP violation
epsilon'/epsilon. In particular, the supersymmetric contribution to
epsilon'/epsilon can be of order the KTeV result, epsilon'/epsilon ~ 10^(-3).

</DOC>
<DOC>
<DOCNO> 151672 </DOCNO>
Born-Infeld Theory and Stringy Causality


  Fluctuations around a non-trivial solution of Born-Infeld theory have a
limiting speed given not by the Einstein metric but the Boillat metric. The
Boillat metric is S-duality invariant and conformal to the open string metric.
It also governs the propagation of scalars and spinors in Born-Infeld theory.
We discuss the potential clash between causality determined by the closed
string and open string light cones and find that the latter never lie outside
the former. Both cones touch along the principal null directions of the
background Born-Infeld field. We consider black hole solutions in situations in
which the distinction between bulk and brane is not sharp such as space filling
branes and find that the location of the event horizon and the thermodynamic
properties do not depend on whether one uses the closed or open string metric.
Analogous statements hold in the more general context of non-linear
electrodynamics or effective quantum-corrected metrics. We show how Born-Infeld
action to second order might be obtained from higher-curvature gravity in
Kaluza-Klein theory. Finally we point out some intriguing analogies with
Einstein-Schr\"odinger theory.

</DOC>
<DOC>
<DOCNO> 84119 </DOCNO>
The Planck quantum hypothesis and the Friedmannian models of flat


  Only one model from an infinite number of the Friedmannian models of flat
expansive isotropic and homogeneous universe satisfies the assumptions
resulting from the Planck quantum hypothesis.

</DOC>
<DOC>
<DOCNO> 80751 </DOCNO>
A note on the practical feasibility of domain-wall fermions


  Domain-wall fermions preserve chiral symmetry up to terms that decrease
exponentially when the lattice size in the fifth dimension is taken to
infinity. The associated rates of convergence are given by the low-lying
eigenvalues of a simple local operator in four dimensions. These can be
computed using the Ritz functional technique and it turns out that the
convergence tends to be extremely slow in the range of lattice spacings
relevant to large-volume numerical simulations of lattice QCD. Two methods to
improve on this situation are discussed.

</DOC>
<DOC>
<DOCNO> 13607 </DOCNO>
Generation of unpredictable time series by a Neural Network


  A perceptron that learns the opposite of its own output is used to generate a
time series. We analyse properties of the weight vector and the generated
sequence, like the cycle length and the probability distribution of generated
sequences. A remarkable suppression of the autocorrelation function is
explained, and connections to the Bernasconi model are discussed. If a
continuous transfer function is used, the system displays chaotic and
intermittent behaviour, with the product of the learning rate and amplification
as a control parameter.

</DOC>
<DOC>
<DOCNO> 120961 </DOCNO>
Effects of Environment and Energy Injection on Gamma-Ray Burst


  There is growing evidence that some long gamma-ray bursts (GRBs) arise from
the core collapse of massive stars, and thus it is inevitable that the
environments of these GRBs are preburst stellar winds or dense media. We
studied, for the first time, the wind model for afterglows based on the
Blandford-McKee self-similar solution of a relativistic shock, and suggested
that GRB 970616 is an interactor with a stellar wind. We also proposed a dense
medium model for some afterglows, e.g., the steepening in the light curve of
the R-band afterglow of GRB 990123 may be caused by the adiabatic shock which
has evolved from an ultrarelativistic phase to a nonrelativistic phase in a
dense medium. We further discussed the dense medium model in more details, and
investigated the effects of synchrotron self absorption and energy injection. A
shock in a dense medium becomes nonrelativistic rapidly after a short
relativistic phase. The afterglow from the shock at the nonrelativistic stage
decays more rapidly than at the relativistic stage. Since some models for GRB
energy sources predicted that a strongly magnetic millisecond pulsar may be
born during GRB formation, we discussed the effect of such a pulsar on the
evolution of the nonrelativistic shock through magnetic dipole radiation. We
found that in the pulsar energy injection case, the dense medium model fits
very well all the observational data of GRB 980519. Recently, we combined the
dense medium model with the pulsar energy injection effect to provide a good
fit to the optical afterglow data of GRB 000301C.

</DOC>
<DOC>
<DOCNO> 117796 </DOCNO>
Mapping the Galactic Halo I. The `Spaghetti' Survey


  We describe a major survey of the Milky Way halo designed to test for
kinematic substructure caused by destruction of accreted satellites. We use the
Washington photometric system to identify halo stars efficiently for
spectroscopic followup. Tracers include halo giants (detectable out to more
than 100 kpc), blue horizontal branch stars, halo stars near the main sequence
turnoff, and the ``blue metal-poor stars'' of Preston et al (1994). We
demonstrate the success of our survey by showing spectra of stars we have
identified in all these categories, including giants as distant as 75 kpc. We
discuss the problem of identifying the most distant halo giants. In particular,
extremely metal-poor halo K dwarfs are present in approximately equal numbers
to the distant giants for V fainter than 18, and we show that our method will
distinguish reliably between these two groups of metal-poor stars. We plan to
survey 100 square degrees at high galactic latitude, and expect to increase the
numbers of known halo giants, BHB stars and turnoff stars by more than an order
of magnitude. In addition to the strong test that this large sample will
provide for the question `was the Milky Way halo accreted from satellite
galaxies?', we will improve the accuracy of mass measurements of the Milky Way
beyond 50 kpc via the kinematics of the many distant giants and BHB stars we
will find. We show that one of our first datasets constrains the halo density
law over galactocentric radii of 5-20 kpc and z heights of 2-15 kpc. The data
support a flattened power-law halo with b/a of 0.6 and exponent -3.0. More
complex models with a varying axial ratio may be needed with a larger dataset.

</DOC>
<DOC>
<DOCNO> 71407 </DOCNO>
Mixing of scalar glueballs and flavour-singlet scalar mesons


  We discuss in detail the extraction of hadronic mixing strengths from lattice
studies. We apply this to the mixing of a scalar glueball and a scalar meson in
the quenched approximation. We also measure correlations appropriate for
flavour-singlet scalar mesons using dynamical quark configurations from UKQCD.
This enables us to compare the results from the quenched study of the mixing
with the direct determination of the mixed spectrum. Improved methods of
evaluating the disconnected quark diagrams are also presented.

</DOC>
<DOC>
<DOCNO> 150936 </DOCNO>
Intersecting branes with an arbitrary excess angle


  We find all possible static embeddings of a 4-brane in any dimension-6
spacetime with 4-dimensional Poincare symmetry and a negative cosmological
constant, subject to orbifolding across the brane. Our new solutions allow
intersecting branes at an angle determined by a new dynamical parameter. A
collection of branes intersecting in one 3-brane allows an arbitrary excess
angle that can be related to a vacuum density along the intersection. The
3-brane must be stabilized by additional fine-tuned interactions. We also note
that localization of gravity is tied to the approximate fine tuning of the
brane tensions.

</DOC>
<DOC>
<DOCNO> 84356 </DOCNO>
Scalar fields, energy conditions, and traversable wormholes


  We describe the different possibilities that a simple and apparently quite
harmless classical scalar field theory provides to violate the energy
conditions. We demonstrate that a non-minimally coupled scalar field with a
positive curvature coupling xi>0 can easily violate all the standard energy
conditions, up to and including the averaged null energy condition (ANEC).
Indeed this violation of the ANEC suggests the possible existence of
traversable wormholes supported by non-minimally coupled scalars. To
investigate this possibility we derive the classical solutions for gravity plus
a general (arbitrary xi) massless non-minimally coupled scalar field,
restricting attention to the static and spherically symmetric configurations.
Among these classical solutions we find an entire branch of traversable
wormholes for every xi>0. (This includes and generalizes the case of conformal
coupling xi=1/6 we considered in Phys. Lett. B466 (1999) 127--134;
gr-qc/9908029) For these traversable wormholes to exist we demonstrate that the
scalar field must reach trans-Planckian values somewhere in the geometry. We
discuss how this can be accommodated within the current state of the art
regarding scalar fields in modern theoretical physics. We emphasize that these
scalar field theories, and the traversable wormhole solutions we derive, are
compatible with all known experimental constraints from both particle physics
and gravity.

</DOC>
<DOC>
<DOCNO> 80880 </DOCNO>
Light hadron spectroscopy with two flavors of O(a) improved dynamical


  We report on our study of light hadron spectrum and quark masses in QCD with
two flavors of dynamical quarks. Simulations are made with the plaquette gauge
action and the non-perturbatively $O(a)$ improved Wilson quark action. We
simulate 5 sea qaurk masses corresponding to $m_{PS}/m_{V} \simeq 0.8$--0.6 at
$\beta=5.2$ on $12^3 \times 48$, $16^3 \times 48$ and $20^3 \times 48$
lattices. A comparison with previous calculations in quenched QCD indicates sea
quark effects in meson and quark masses.

</DOC>
<DOC>
<DOCNO> 178557 </DOCNO>
Why is the three-nucleon force so odd?


  By considering a class of diagrams which has been overlooked also in the most
recent literature on three-body forces, we extract a new contribution to the
three-nucleon interaction which specifically acts on the triplet odd states of
the two nucleon subsystem. In the static approximation, this 3N-force
contribution is fixed by the underlying 2N interaction, so in principle there
are no free parameters to adjust. The 2N amplitude however enters in the 3NF
diagram in a form which cannot be directly accessed or constrained by NN
phase-shift analysis. We conclude that this new 3N-force contribution provides
a mechanism which implies that the presence of the third nucleon modifies the
p-wave (and possibly the f-wave) components of the 2N subsystem in the
triplet-isotriplet channels.

</DOC>
<DOC>
<DOCNO> 119988 </DOCNO>
Implications of mean field accretion disc theory for vorticity and


  In addition to the scalar Shakura-Sunyaev $\alpha_{ss}$ turbulent viscosity
transport term used in simple analytic accretion disc modeling, a pseudoscalar
transport term also arises. The essence of this term can be captured even in
simple models for which vertical averaging is interpreted as integration over a
half-thickness and one separately studies each hemisphere. The additional term
highlights a complementarity between mean field magnetic dynamo theory and
accretion disc theory treated as a mean field theory. Such pseudoscalar terms
have been studied, and can lead to large scale magnetic field and vorticity
growth. Here it is shown that vorticity can grow even in the simplest azimuthal
and half-height integrated disc model, for which mean quantities depend only on
radius. The simplest vorticity growth solutions seem to have scales and vortex
survival times consistent those required for facilitating planet formation.
Also it is shown that when the magnetic back-reaction is included to lowest
order, the pseudoscalar driving the magnetic field growth and that driving the
vorticity growth will behave differently with respect to shearing and
non-shearing flows: the former can reverse sign in the two cases, while the
latter will have the same sign.

</DOC>
<DOC>
<DOCNO> 83178 </DOCNO>
Information Extraction from Broadcast News


  This paper discusses the development of trainable statistical models for
extracting content from television and radio news broadcasts. In particular we
concentrate on statistical finite state models for identifying proper names and
other named entities in broadcast speech. Two models are presented: the first
represents name class information as a word attribute; the second represents
both word-word and class-class transitions explicitly. A common n-gram based
formulation is used for both models. The task of named entity identification is
characterized by relatively sparse training data and issues related to
smoothing are discussed. Experiments are reported using the DARPA/NIST Hub-4E
evaluation for North American Broadcast News.

</DOC>
<DOC>
<DOCNO> 10580 </DOCNO>
Electrostatic Attraction of Coupled Wigner Crystals: Finite Temperature


  In this paper, we present a unified physical picture for the electrostatic
attraction between two coupled planar Wigner crystals at finite (but below
their melting) temperature. At very low temperatures, we find a new regime
where the attraction, arising from the long-wavelength excitation of the
plasmon mode, scales with the interplanar distance $d$ as $d^{-2}$. At higher
temperatures, our calculation agrees with known results. Furthermore, we
analyze the temperature dependence of the short-ranged attraction arising from
``structural'' correlations and argue that thermal fluctuations drastically
reduce the strength of this attraction.

</DOC>
<DOC>
<DOCNO> 151685 </DOCNO>
Three-Dimensional SCFTs, Supersymmetric Domain Wall and Renormalization


  By analyzing SU(3)xU(1) invariant stationary point, studied earlier by
Nicolai and Warner, of gauged N=8 supergravity, we find that the deformation of
S^7 gives rise to nontrivial renormalization group flow in a three-dimensional
boundary super conformal field theory from N=8, SO(8) invariant UV fixed point
to N=2, SU(3)xU(1) invariant IR fixed point. By explicitly constructing
28-beins u, v fields, that are an element of fundamental 56-dimensional
representation of E_7, in terms of scalar and pseudo-scalar fields of gauged
N=8 supergravity, we get A_1, A_2 tensors. Then we identify one of the
eigenvalues of A_1 tensor with ``superpotential'' of de Wit-Nicolai scalar
potential and discuss four-dimensional supergravity description of
renormalization group flow, i.e. the BPS domain wall solutions which are
equivalent to vanishing of variation of spin 1/2, 3/2 fields in the
supersymmetry preserving bosonic background of gauged N=8 supergravity. A
numerical analysis of the steepest descent equations interpolating two critical
points is given.

</DOC>
<DOC>
<DOCNO> 10298 </DOCNO>
Two-component model of a spin-polarized transport


  Effect of the spin-involved interaction of electrons with impurity atoms or
defects to the transport properties of a two-dimensional electron gas is
described by using a simplifying two-component model. Components representing
spin-up and spin-down states are supposed to be coupled at a discrete set of
points within a conduction channel. The used limit of the short-range
interaction allows to solve the relevant scattering problem exactly. By varying
the model parameters different transport regimes of two-terminal devices with
ferromagnetic contacts can be described. In a quasi-ballistic regime the
resulting difference between conductances for the parallel and antiparallel
orientation of the contact magnetization changes its sign as a function of the
length of the conduction channel if appropriate model parameters are chosen.
The effect is in agreement with recent experimental observations.

</DOC>
<DOC>
<DOCNO> 68506 </DOCNO>
Quark-Gluon Plasma: Status of Heavy Ion Physics


  Lattice quantum chromodynamics (QCD), defined on a discrete space time
lattice, leads to a spectacular non-perturbative prediction of a new state of
matter, called quark-gluon plasma (QGP), at sufficiently high temperatures or
equivalently large energy densities. The experimental programs of CERN, Geneva
and BNL, New York of relativistic heavy ion collisions are expected to produce
such energy densities, thereby providing us a chance to test the above
prediction. After a brief introduction of the necessary theoretical concepts, I
will present a critical review of the experimental results already obtained by
the various experiments in order to examine whether QGP has already been
observed by them.

</DOC>
<DOC>
<DOCNO> 118656 </DOCNO>
Constraints on the Stellar/Sub-stellar Mass Function in the Inner Orion


  We present the results of a 0.5-0.9" FWHM imaging survey at K (2.2 micron)
and H (1.6 micron) covering 5.1' x 5.1' centered on Theta 1C Ori, the most
massive star in the Orion Nebula Cluster (ONC). At the age and distance of this
cluster, and in the absence of extinction, the hydrogen burning limit (0.08 Mo)
occurs at K~13.5 mag while an object of mass 0.02 Mo has K~16.2 mag. Our
photometry is complete for source detection at the 7 sigma level to K~17.5 mag
and thus is sensitive to objects as low-mass as 0.02 Mo seen through visual
extinction values as high as 10 magnitudes. We use the observed magnitudes,
colors, and star counts to constrain the shape of the inner ONC stellar mass
function across the hydrogen burning limit. After determining the stellar age
and near-infrared excess properties of the optically visible stars in this same
inner ONC region, we present a new technique that incorporates these
distributions when extracting the mass function from the observed density of
stars in the K-(H-K) diagram. We find that our data are inconsistent with a
mass function that rises across the stellar/sub-stellar boundary. Instead, we
find that the most likely form of the inner ONC mass function is one that rises
to a peak around 0.15 Mo, and then declines across the hydrogen-burning limit
with slope N(log M) ~ M^(0.57+/-0.05). We emphasize that our conclusions apply
to the inner 0.71 pc x 0.71 pc of the ONC only; they may not apply to the ONC
as a whole where some evidence for general mass segregation has been found.

</DOC>
<DOC>
<DOCNO> 120494 </DOCNO>
Shallow cores in the dark matter halos: self-interaction in action?


  Using observational data for a sample of dark matter dominated galaxies and
two cluster of galaxies, we have found that the central halo density does not
depend on its mass, and the core radius is roughly proportional to the maximum
rotation velocity. A good agreement with these scaling laws is obtained for CDM
halos whose dense inner parts were expanded by gravothermal instabilities if
the particles efficiently self-interact only in these parts. We find that the
particle cross-section is inversely proportional to the velocity dispersion.

</DOC>
<DOC>
<DOCNO> 117729 </DOCNO>
Constraints on Photometric Calibration from Observations of


  The good match of the type Ia supernova (SNIa) Hubble Diagram to the
prediction of a not-unreasonable cosmological world model shows that
measurements of standard stars and their comparison with point sources down to
m=25 mag is good to better than +/-0.5 mag over an 11 mag range. It also shows
that the true spectral energy distribution (SED) shapes of standard stars are
known to better than +/-0.5 mag over an octave in wavelength. On the other
hand, the SNIa argument for an accelerating Universe assumes that the magnitude
system is good to much better than ~0.1 mag over the 11 mag range, and that SED
shapes are known to much better than ~10 percent over an octave in wavelength.
There is no independent empirical evidence for these plausible assumptions.

</DOC>
<DOC>
<DOCNO> 152169 </DOCNO>
Seiberg-Witten theory for the asymptotic free rank three tensors of


  We here give a first indication that there exists a Seiberg-Witten curve for
  SU(N) Seiberg-Witten theory with matter transforming in the totally
antisymmetric rank three tensor representation. We present a derivation of the
leading order hyperelliptic approximation of a curve for this case. Since we
are only interested in the asymptotic free theory we are restricted to
$N=6,7,8$. The derivation is carried out by reversed engineering starting from
the known form of the prepotential at tree level. We also predict the form of
the one instanton correction to the prepotential.

</DOC>
<DOC>
<DOCNO> 9998 </DOCNO>
Exact sampling from non-attractive distributions using summary states


  Propp and Wilson's method of coupling from the past allows one to efficiently
generate exact samples from attractive statistical distributions (e.g., the
ferromagnetic Ising model). This method may be generalized to non-attractive
distributions by the use of summary states, as first described by Huber. Using
this method, we present exact samples from a frustrated antiferromagnetic
triangular Ising model and the antiferromagnetic q=3 Potts model. We discuss
the advantages and limitations of the method of summary states for practical
sampling, paying particular attention to the slowing down of the algorithm at
low temperature. In particular, we show that such a slowing down can occur in
the absence of a physical phase transition.

</DOC>
<DOC>
<DOCNO> 117001 </DOCNO>
CW Performance of the Triumf 8 Meter Long RFQ for Exotic Ions


  The ISAC 35 MHz RFQ is designed to accelerate ions of A/q up to 30 from
2keV/u to 150keV/u in cw mode. The RFQ structure is 8 meters long and the
vane-shaped rods are supported by 19 rings spaced 40 cm apart. An unusual
feature of the design is the constant synchronous phase of -25; the buncher and
shaper sections are eliminated in favor of an external multi-harmonic buncher.
All 19 rings are installed with quadrature positioning of the four rod
electrodes aligned to +/- 0.08 mm. Relative field variation and quadruple
asymmetry along the 8 meters of the RFQ was measured to be within +/- 1%. Early
operation at peak inter-electrode voltage (75kV) was restricted by the rapid
growth of dark currents due to field emission; the nominal operating power of
75 kW increased to 100 kW in a few hours. A program of high power pulsing,
followed by cw operation have all but eliminated the problem leading to a
successful 150 hour test at full power. Successful beam test results confirm
beam dynamics and rf designs.

</DOC>
<DOC>
<DOCNO> 122719 </DOCNO>
Simulations of Deep Pencil-Beam Redshift Surveys


  We create mock pencil-beam redshift surveys from very large cosmological
$N$-body simulations of two Cold Dark Matter cosmogonies, an Einstein-de Sitter
model ($\tau$CDM) and a flat model with $\Omega_0 =0.3$ and a cosmological
constant ($\Lambda$CDM). We use these to assess the significance of the
apparent periodicity discovered by Broadhurst et al. (1990). Simulation
particles are tagged as `galaxies' so as to reproduce observed present-day
correlations. They are then identified along the past light-cones of
hypothetical observers to create mock catalogues with the geometry and the
distance distribution of the Broadhurst et al. data. We produce 1936 (2625)
quasi-independent catalogues from our $\tau$CDM ($\Lambda$CDM) simulation. A
couple of large clumps in a catalogue can produce a high peak at low
wavenumbers in the corresponding one-dimensional power spectrum, without any
apparent large-scale periodicity in the original redshift histogram. Although
the simulated redshift histograms frequently display regularly spaced clumps,
the spacing of these clumps varies between catalogues and there is no
`preferred' period over our many realisations. We find only a 0.72 (0.49) per
cent chance that the highest peak in the power spectrum of a $\tau$CDM
($\Lambda$CDM) catalogue has a peak-to-noise ratio higher than that in the
Broadhurst et al. data. None of the simulated catalogues with such high peaks
shows coherently spaced clumps with a significance as high as that of the real
data. We conclude that in CDM universes, the kind of regularity observed by
Broadhurst et al. has a priori probability well below $10^{-3}$.

</DOC>
<DOC>
<DOCNO> 100569 </DOCNO>
Pluricanonical maps of varieties of maximal Albanese dimension


  Let $X$ be a smooth complex projective algebraic variety of maximal Albanese
dimension. We give a characterization of $\kappa (X)$ in terms of the set
$V^0(X,\omega_{X})$ $:=\{P\in {\text{\rm Pic}}^0(X)|h^0(X, \omega_X \otimes P)
\ne 0\}$. An immediate consequence of this is that the Kodaira dimension
$\kappa (X)$ is invariant under smooth deformations. We then study the
pluricanonical maps $\phi_m:X -> \Bbb{P} (H^0(X,mK_X))$. We prove that if $X$
is of general type, $\phi_m$ is generically finite for $m\geq 5$ and birational
for $m\geq 5 \text{\rm dim} (X) +1$. More generally, we show that for $m\geq 6$
the image of $\phi_m$ is of dimension equal to $\kappa (X)$ and for $m\geq
6\kappa (X)+2$, $\phi_m$ is the stable canonical map.

</DOC>
<DOC>
<DOCNO> 116930 </DOCNO>
Main steps for the fabrication of IPHI RFQ


  The RFQ of the project IPHI is a 8 meter long, high power, very precise
tolerances (0.01 mm on 1 meter long for example) device to accelerate protons.
This RFQ is similar to the RFQ of the LEDA project. So, we realize a thermal
and mechanical studies followed by different tests for machining and brazing
copper. We describe in this paper those different steps and the way we proceed
to supply the fabrication itself by an independent company.

</DOC>
<DOC>
<DOCNO> 68768 </DOCNO>
Higgs Decay into Gravitons: Trees and Loops


  The decay of the Higgs particle into two gravitons was previously calculated
by us using a Born term from the Einstein field equations. Subsequently, others
computed the same decay via one loop diagrams but omitting the Born terms. Here
all of the diagrams up to one loop are discussed, and it is shown that the Born
term is overwhelmingly dominant in agreement with our original results.

</DOC>
<DOC>
<DOCNO> 100084 </DOCNO>
Irregular Input Data in Convergence Acceleration and Summation


  Sequence transformations accomplish an acceleration of convergence or a
summation in the case of divergence by detecting and utilizing regularities of
the elements of the sequence to be transformed. For sufficiently large indices,
certain asymptotic regularities normally do exist, but the leading elements of
a sequence may behave quite irregularly. The Gaussian hypergeometric series 2F1
(a, b; c; z) is well suited to illuminate problems of that kind. Sequence
transformations perform quite well for most parameters and arguments. If,
however, the third parameter $c$ of a nonterminating hypergeometric series 2F1
is a negative real number, the terms initially grow in magnitude like the terms
of a mildly divergent series. The use of the leading terms of such a series as
input data leads to unreliable and even completely nonsensical results. In
contrast, sequence transformations produce good results if the leading
irregular terms are excluded from the transformation process. Similar problems
occur also in perturbation expansions. For example, summation results for the
infinite coupling limit k_3 of the sextic anharmonic oscillator can be improved
considerably by excluding the leading terms from the transformation process.
Finally, numerous new recurrence formulas for the 2F1 (a, b; c; z) are derived.

</DOC>
<DOC>
<DOCNO> 71224 </DOCNO>
Space--Time Symmetry, CPT and Mirror Fermions


  The motivations for the construction of an 8-component representation of
fermion fields based on a two dimensional representation of time reversal
transformation and CPT invariance are discussed. Some of the elementary
properties of the quantum field theory in the 8-component representation are
studied. It includes the space-time and charge conjugation symmetries, the
implementation of a reality condition, the construction of interaction
theories, the field theoretical imaginary- and real-time approach to
thermodynamics of fermionic systems, the quantization of fermion fields, their
particle content and the Feynman rules for perturbation theories. It is shown
that in the new presentation, a CPT violation can be formulated in principle.
The construction of interaction theories in the 8-component theory for fermions
is shown to be constrained by the CPT invariance. The short distance behavior
and relativistic covariance are studied. In the path integral representation of
the thermodynamical potential, the conventional imaginary-time approach is
shown to be smoothly connected to a real-time thermal field theory in the
8-component representation for fermion fields without any additional
subtraction of infinities. The metastability at zero density and the nature of
the spontaneous CP violation in color superconducting phases of strong
interaction ground states are clarified.

</DOC>
<DOC>
<DOCNO> 71624 </DOCNO>
Supersymmetric CP-violating Currents and Electroweak Baryogenesis


  In this work we compute the CP-violating currents of the right-handed stops
and Higgsinos, induced by the presence of non-trivial vacuum expectation values
of the Higgs fields within the context of the minimal supersymmetric extension
of the Standard Model (MSSM) with explicit CP-violating phases. Using the
Keldysh formalism, we perform the computation of the currents at finite
temperature, in an expansion of derivatives of the Higgs fields. Contrary to
previous works, we implement a resummation of the Higgs mass insertion effects
to all orders in perturbation theory. While the components of the right-handed
stop current j^\mu_{\widetilde t_R} become proportional to the difference H_2
\partial^{\mu}H_1-H_1 \partial^{\mu} H_2 (suppressed by \Delta\beta), the
Higgsino currents, j^\mu_{\widetilde{H}_i}, present contributions proportional
to both H_2 \partial^{\mu}H_1\pm H_1 \partial^{\mu} H_2. For large values of
the charged Higgs mass and moderate values of \tan\beta the contribution to the
source proportional to H_2 \partial^{\mu}H_1+H_1 \partial^{\mu} H_2 in the
diffusion equations become sizeable, although it is suppressed by the Higgsino
number violating interaction rate \Gamma_\mu^{-1/2}. For small values of the
wall velocity, 0.04\simlt v_\omega \simlt 0.1, the total contribution leads to
acceptable values of the baryon asymmetry for values of the CP-violating phases
\phi_{CP} in the range 0.04\simlt|\sin\phi_{CP}|\simlt 1. Finally, we comment
on the relevance of the latest results of Higgs searches at LEP2 for the
mechanism of electroweak baryogenesis within the MSSM.

</DOC>
<DOC>
<DOCNO> 70844 </DOCNO>
The mystery of cosmological vacuum energy density and the accelerated


  The principles of General Relativity allow for a non-vanishing cosmological
constant, which can possibly be interpreted at least partially in terms of
quantum-fluctuations of matter fields. Depending on sign and magnitude it can
cause accelerated or decelerated expansion at certain stages of cosmic
evolution. Recent observations in cosmology seem to indicate that we presently
live in an accelerated phase. We recall the history and fundamental issues
connected with the cosmological constant and then discuss present evidences for
a positive value, which causes the accelerated expansion.

</DOC>
<DOC>
<DOCNO> 100060 </DOCNO>
Attainable sets for left invariant control systems and


  Let $G$ be a semidirect product of a simply connected nilpotent Lie group and
$\R$. For a left invariant control system on $G$ with a convex cone as a
control domain, it is proved that the attainable sets coincides with a
"halfspace" if the degree of contact of the with some special subspaces is
sufficiently high.

</DOC>
<DOC>
<DOCNO> 12975 </DOCNO>
Field-theory for reaction-diffusion processes with hard-core particles


  We show how to build up a systematic bosonic field-theory for a general
reaction-diffusion process involving hard-core particles in arbitrary
dimension. We criticize a recent approach proposed by Park, Kim and Park (Phys.
Rev. E 62 (2000)). As a testbench for our method, we show how to recover the
equivalence between asymmetric diffusion of excluding particles and the noisy
Burgers equation.

</DOC>
<DOC>
<DOCNO> 119037 </DOCNO>
FUSE Observations of Intrinsic Absorption in the Seyfert 1 Galaxy Mrk


  We present far-ultraviolet spectra of the Seyfert 1 galaxy Mrk 509 obtained
in 1999 November with the Far Ultraviolet Spectroscopic Explorer (FUSE). Our
data span the observed wavelength range 915-1185 A at a resolution of ~20 km/s.
The spectrum shows a blue continuum, broad OVI 1032,1038 emission, and a broad
CIII 977 emission line. Superposed on these emission components, we resolve
associated absorption lines of OVI 1032,1038, CIII 977, and Lyman lines through
Lzeta. Seven distinct kinematic components are present, spanning a velocity
range of -440 to +170 km/s relative to the systemic velocity. The absorption is
clustered in two groups, one centered at -370m km/s and another at the systemic
velocity. The blue-shifted cluster may be associated with the extended line
emission visible in deep images of Mrk 509 obtained by Phillips et al. Although
several components appear to be saturated, they are not black at their centers.
Partial covering or scattering permits ~7% of the broad-line or continuum flux
to be unaffected by absorption. Of the multiple components, only one has the
same ionization state and column density as highly ionized gas that produces
the OVII and OVIII ionization edges in X-ray spectra of Mrk 509.
  This paper will appear in a special issue of Astrophysical Journal Letters
devoted to the first scientific results from the FUSE mission.

</DOC>
<DOC>
<DOCNO> 71910 </DOCNO>
Suggestions for Identifying the Primary of Post-GZK Air Showers


  A procedure is suggested for systematically narrowing the choice of possible
primaries for (UHECR) air showers with energies beyond the
Greisen-Zatsepin-Kuz'min cut-off of $4 \times 10^{19} eV$.

</DOC>
<DOC>
<DOCNO> 39979 </DOCNO>
Effective Lagrangian induced by the anomalous Wess-Zumino action and the


  A simple model for the exotic waves with $I^G(J^{PC})=1^-(1^{-+})$ in the
reactions $VP\to VP$, $VP\to PP$, and $PP\to PP$ is constructed beyond the
scope of the quark-gluon approach. The model satisfies unitarity and
analyticity and uses as a "priming" the "anomalous" nondiagonal $VPPP$
interaction which couples together the four channels $\rho\pi$, $\eta\pi$,
$\eta'\pi$, and $K^*\bar K+\bar K^*K$. The possibility of the resonancelike
behavior of the $I^G(J^{PC})=1^-(1^{-+})$ amplitudes belonging to the $\{10\}-
\{\bar{10}\}$ and $\{8\}$ representations of SU(3) as well as their mixing is
demonstrated explicitly in the $1.3-1.6$ GeV mass range which, according to the
current experimental evidence, is really rich in exotics.

</DOC>
<DOC>
<DOCNO> 101784 </DOCNO>
Finite quantum groups over abelian groups of prime exponent


  Since the discovery of quantum groups (Drinfeld, Jimbo) and finite
dimensional variations thereof (Lusztig, Manin), these objects were studied
from different points of view and had many applications. The present paper is
part of a series where we intend to show that important classes of Hopf
algebras are quantum groups and therefore belong to Lie theory. One of our main
results is the explicit construction of a general family of pointed Hopf
algebras from Dynkin diagrams. All the Frobenius-Lusztig kernels and their
parabolic subalgebras belong to this family, but in addition we get many new
examples. We show that any finite dimensional pointed Hopf algebra with group
of prime exponent (greater than 17) is indeed in this family. An important step
in the proof follows from a another result, where we show that a wide family of
finite dimensional pointed Hopf algebras is generated by group-like and
skew-primitive elements, giving additional support to a conjecture in our
previous paper "Finite quantum groups and Cartan matrices", Adv. Math. 154
(2000), 1--45.

</DOC>
<DOC>
<DOCNO> 11569 </DOCNO>
X-Ray Scattering Evidence for Macroscopic Strong Pinning Centers in the


  Using high-resolution X-ray scattering techniques, we measure the variation,
q(x), of the position in reciprocal space of the CDW satellite, in the sliding
state, along the length of NbSe_3 whiskers. We show that structural defects and
intentionally X-ray radiation-damaged regions increase locally the CDW pinning
force, and induce CDW phase distortions which are consistent with those
observed near contacts. Using the semi-microscopic model from Brazovskii
describing the normal-condensed carrier conversion, with spatially varying
parameters, we account for the experimental spatial dependence of the CDW phase
gradient near both types of defects.

</DOC>
<DOC>
<DOCNO> 71477 </DOCNO>
NJL model in Four Dimension at Finite Temperature, Chemical Potentialand


  Two flavor Nambu-Jona-Lasinio model with N components is studied in curved
space time at finite temperature and density in the leading 1/N expansion. In
four space time dimension the model exhibits first order phase transition for
positive curvature. Whereas in flat space an increase in temperature induces a
second order phase transition even at finite density, in curved space the
transition becomes first order. We obtain the phase boundary in
density-temperature plane and exhibit its behavior with changing curvature. A
three dimensional plot of the phase boundary in $\mu$-T-R space is drawn.

</DOC>
<DOC>
<DOCNO> 71637 </DOCNO>
Synchronisation and MSW sharpening of neutrinos propagating in a flavour


  We consider neutrino oscillations in a medium in which scattering processes
are blind to the neutrino flavour. We present an analytical derivation of the
synchronised behaviour obtained in the limit where the average scattering rate
is much larger than the oscillation frequency. We also examine MSW transitions
in these circumstances, and show that a sharpening of the transition can
result.

</DOC>
<DOC>
<DOCNO> 151231 </DOCNO>
AdS in Warped Spacetimes


  We obtain a large class of AdS spacetimes warped with certain internal spaces
in eleven-dimensional and type IIA/IIB supergravities. The warp factors depend
only on the internal coordinates. These solutions arise as the near-horizon
geometries of more general semi-localised multi-intersections of $p$-branes. We
achieve this by noting that any sphere (or AdS spacetime) of dimension greater
than 3 can be viewed as a foliation involving S^3 (or AdS_3). Then the S^3 (or
AdS_3) can be replaced by a three-dimensional lens space (or a BTZ black hole),
which arises naturally from the introduction of a NUT (or a pp-wave) to the
M-branes or the D3-brane. We then obtain multi-intersections by performing a
Kaluza-Klein reduction or Hopf T-duality transformation on the fibre coordinate
of the lens space (or the BTZ black hole). These geometries provide further
possible examples of the AdS/CFT correspondence and of consistent embeddings of
lower-dimensional gauged supergravities in D=11 or D=10.

</DOC>
<DOC>
<DOCNO> 13737 </DOCNO>
Space-time versus particle-hole symmetry in quantum Enskog equations


  The non-local scattering-in and -out integrals of the Enskog equation have
reversed displacements of colliding particles reflecting that the -in and -out
processes are conjugated by the space and time inversions. Generalisations of
the Enskog equation to Fermi liquid systems are hindered by a request of the
particle-hole symmetry which contradicts the reversed displacements. We resolve
this problem with the help of the optical theorem. It is found that space-time
and particle-hole symmetry can only be fulfilled simultaneously for the
Bruckner-type of internal Pauli-blocking while the Feynman-Galitskii form
allows only for particle-hole symmetry but not for space-time symmetry due to a
stimulated emission of Bosons.

</DOC>
<DOC>
<DOCNO> 122183 </DOCNO>
Analysis of the Type IIn Supernova 1998S: Effects of Circumstellar


  We present spectral analysis of early observations of the Type IIn supernova
1998S using the general non-local thermodynamic equilibrium atmosphere code \tt
PHOENIX}. We model both the underlying supernova spectrum and the overlying
circumstellar interaction region and produce spectra in good agreement with
observations. The early spectra are well fit by lines produced primarily in the
circumstellar region itself, and later spectra are due primarily to the
supernova ejecta. Intermediate spectra are affected by both regions. A
mass-loss rate of order $\dot M \sim 0.0001-0.001$\msol yr$^{-1}$ is inferred
for a wind speed of 100-1000 \kmps. We discuss how future self-consistent
models will better clarify the underlying progenitor structure.

</DOC>
<DOC>
<DOCNO> 101957 </DOCNO>
Minimizers of the Lawrence-Doniach energy in the small-coupling limit:


  In this paper we study the Lawrence-Doniach model for layered
superconductors, for a sample with finite width subjected to a magnetic field
parallel to the superconducting layers. We provide a rigorous analysis of the
energy minimizers in the limit as the coupling between adjacent superconducting
layers tends to zero. We identify a unique global minimizer of the Gibbs free
energy in this regime ("vortex planes"), and reveal a sequence of first-order
phase transitions by which Josephson vortices are nucleated via the boundary.
The small coupling limit is studied via degenerate perturbation theory based on
a Lyapunov-Schmidt decomposition which reduces the Lawrence-Doniach system to a
finite-dimensional variational problem. Finally, a lower bound on the radius of
validity of the perturbation expansion (in terms of various parameters
appearing in the model) is obtained.

</DOC>
<DOC>
<DOCNO> 100675 </DOCNO>
The energy of unit vector fields on the 3-sphere


  The stability of the 3-dimensional Hopf vector field, as a harmonic section
of the unit tangent bundle, is viewed from a number of different angles. The
spectrum of the vertical Jacobi operator is computed, and compared with that of
the Jacobi operator of the identity map on the 3-sphere. The variational
behaviour of the 3-dimensional Hopf vector field is compared and contrasted
with that of the closely-related Hopf map. Finally, it is shown that the Hopf
vector fields are the unique global minima of the energy functional restricted
to unit vector fields on the 3-sphere.

</DOC>
<DOC>
<DOCNO> 13989 </DOCNO>
Structural, Electronic, and Magnetic Properties of MnO


  We calculate the structural, electronic, and magnetic properties of MnO from
first principles, using the full-potential linearized augmented planewave
method, with both local-density and generalized-gradient approximations to
exchange and correlation. We find the ground state to be of rhombohedrally
distorted B1 structure with compression along the [111] direction,
antiferromagnetic with type-II ordering, and insulating, consistent with
experiment. We show that the distortion can be understood in terms of a
Heisenberg model with distance dependent nearest-neighbor and
next-nearest-neighbor couplings determined from first principles. Finally, we
show that magnetic ordering can induce significant charge anisotropy, and give
predictions for electric field gradients in the ground-state rhombohedrally
distorted structure.

</DOC>
<DOC>
<DOCNO> 152364 </DOCNO>
Vacuum energy in the background of delta potentials


  The response of vacuum to the presence of external conditions is the subject
of this work. We consider a generalization of the Casimir effect in the
presence of curved boundaries on which a sharp potential is concentrated. The
profile of the potential is a delta function, which has some features in common
with a hard boundary and some with a smooth background field. The boundaries
investigated are: i) a spherical shell, ii) a cylindrical shell, iii) a
magnetic flux tube. The vacuum energy is calculated by means of the Jost
function of the scattering problem related to the field equation. The energy is
then renormalized by means of a zeta functional approach adopting the
heat-kernel expansion. The heat kernel coefficients are calculated and a
discussion of the UV-divergences of the model is presented. The renormalized
vacuum energy $E^{ren}$ is then numerically studied and plotted. The sign of
$E^{ren}$ is found to be always negative in the case of the cylindrical shell,
while in the case of the spherical shell and of the magnetic flux tube the sign
depends on the value of the radius.

</DOC>
<DOC>
<DOCNO> 85548 </DOCNO>
Data Processing for LISA's Laser Interferometer Tracking System (LITS)


  The purpose of this paper is twofold. First, we will present recent results
on the data processing for LISA, including algorithms for elimination of clock
jitter noise and discussion of the generation of the data averages that will
eventually need to be telemetered to the ground. Second, we will argue, based
partly on these results, that a laser interferometer tracking system (LITS)
that employs independent lasers in each spacecraft is preferable for reasons of
simplicity to that in which the lasers in two of the spacecraft are locked to
the incoming beam from the third.

</DOC>
<DOC>
<DOCNO> 8724 </DOCNO>
Computational probes of collective excitations in low-dimensional


  The investigation of the dynamics of quantum many-body systems is a concerted
effort involving computational studies of mathematical models and experimental
studies of material samples. Some commonalities of the two tracks of
investigation are discussed in the context of the quantum spin dynamics of
low-dimensional magnetic systems, in particular spin chains. The study of
quantum fluctuations in such systems at equilibrium amounts to exploring the
spectrum of collective excitations and the rate at which they are excited from
the ground state by dynamical variables of interest. The exact results obtained
via Bethe ansatz or algebraic analysis (quantum groups) for a select class of
completely integrable models can be used as benchmarks for numerical studies of
nonintegrable models, for which computational access to the spectrum of
collective excitations is limited.

</DOC>
<DOC>
<DOCNO> 99296 </DOCNO>
Chow groups of weighted hypersurfaces


  We extend a result of to Esnault-Levine-Viehweg concerning the Chow groups of
hypersurfaces in projective space to those in weighted projective spaces.

</DOC>
<DOC>
<DOCNO> 122879 </DOCNO>
Galaxy Cluster Gas Mass Fractions from Sunyaev-Zel'dovich Effect


  Using sensitive centimeter-wave receivers mounted on the Owens Valley Radio
Observatory and Berkeley-Illinois-Maryland-Association millimeter arrays, we
have obtained interferometric measurements of the Sunyaev-Zel'dovich (SZ)
effect toward massive galaxy clusters. We use the SZ data to determine the
pressure distribution of the cluster gas and, in combination with published
X-ray temperatures, to infer the gas mass and total gravitational mass of 18
clusters. The gas mass fraction, f_g, is calculated for each cluster, and is
extrapolated to the fiducial radius r_{500} using the results of numerical
simulations. The mean f_g within r_{500} is 0.081+0.009 -0.011/(h_{100}
(statistical uncertainty at 68% confidence level, assuming OmegaM=0.3,
OmegaL=0.7). We discuss possible sources of systematic errors in the mean f_g
measurement. We derive an upper limit for OmegaM from this sample under the
assumption that the mass composition of clusters within r_{500} reflects the
universal mass composition: Omega_M h < Omega_B/f_g. The gas mass fractions
depend on cosmology through the angular diameter distance and the r_{500}
correction factors.
  For a flat universe (OmegaL = 1 - OmegaM) and h=0.7, we find the measured gas
mass fractions are consistent with Omegam less than 0.40, at 68% confidence.
Including estimates of the baryons contained in galaxies and the baryons which
failed to become bound during the cluster formation process, we find OmegaM
\~0.25.

</DOC>
<DOC>
<DOCNO> 118442 </DOCNO>
2D Numerical Simulation of Stellar Convection


  The dynamics and thermal structure of the surface layers of stars with outer
convection zones can be studied in some detail by means of numerical
simulations of time-dependent compressible convection. In an effort to
investigate the properties of ``stellar granulation'' as a function of spectral
type, we have carried out elaborate 2-dimensional radiation hydrodynamics
calculations of surface convection for a variety of stellar parameters. The
main features of these simulations are reviewed, with particular reference to
standard mixing length models.

</DOC>
<DOC>
<DOCNO> 170700 </DOCNO>
Efficacy of non-locality theorems "without inequalities" for pairs of


  We prove that recent theorems of non-locality without inequalities are not
effective, for systems of two spacelike separated 2-level sub-systems, in
proving non-locality of any empirically valid theory sharing a set of
correlations with quantum theory.

</DOC>
<DOC>
<DOCNO> 72043 </DOCNO>
Mass of the $\eta'$ meson in the chiral limit in the zero momentum modes


  Using the trace anomaly and low energy relations, as well as the
Witten-Veneziano formula for the mass of the $\eta'$ meson, we have developed a
formalism which makes it possible to express the gluon condensate, the
topological susceptibility and the mass of the $\eta'$ meson as a functions of
the truly nonperturbative vacuum energy density which is one of the most
important characteristics of the QCD true ground state. It was directly applied
to the numerical evaluation of the chiral QCD vacuum topological structure
within its quantum zero momentum modes enhancement model. A rather good
agreement with phenomenological and experimental values of the above-mentioned
quantities has been achieved. With the help of the Witten-Veneziano formula, we
derived an absolute lower bounds for the pion decay constant and the mass of
the $\eta'$ meson in the chiral limit. By introducing the most general
parametrization of the gluon condensate, we also proposed how the correct $N_f$
(number of flavors) dependence of its phenomenologically extracted value could
be restored.

</DOC>
<DOC>
<DOCNO> 12276 </DOCNO>
Finite-size scaling at the dynamical transition of the mean-field


  We use Monte Carlo simulations to study the static and dynamical properties
of a Potts glass with infinite range Gaussian distributed exchange interactions
for a broad range of temperature and system size up to N=2560 spins. The
results are compatible with a critical divergence of the relaxation time tau at
the theoretically predicted dynamical transition temperature T_D, tau \propto
(T-T_D)^{-\Delta} with Delta \approx 2. For finite N a further power law at
T=T_D is found, tau(T=T_D) \propto N^{z^\star} with z^\star \approx 1.5 and for
T>T_D dynamical finite-size scaling seems to hold. The order parameter
distribution P(q) is qualitatively compatible with the scenario of a first
order glass transition as predicted from one-step replica symmetry breaking
schemes.

</DOC>
<DOC>
<DOCNO> 101433 </DOCNO>
Some remarks on the characters of the general Lie superalgebra


  We compute an explicit formula the Hilbert (Poincar\'e) series for the ring
of hook Schur functions and (equivalently) the generating function for
partitions which fit in a $(k,l)$-hook.

</DOC>
<DOC>
<DOCNO> 121852 </DOCNO>
An X-ray flare from the Lindroos binary system HD 560


  We report on a large X-ray flare from the Lindroos binary system HD 560
during a pointed ROSAT PSPC observation. Strong magnetic activity is expected
for the late-type component (a G dwarf star and post-T Tauri Star candidate).
The system is unresolved in the ROSAT image. Therefore, although not expected
from a theoretical point of view, it can not be excluded that the flare has
erupted on the primary, a late-B type star. We discuss the luminosity and
temperature evolution comparing the quiescent and the flare state of HD 560,
and present arguments for the G star as host of the flare.

</DOC>
<DOC>
<DOCNO> 121402 </DOCNO>
RX J1420.4+5334 - another tidal disruption event?


  We have discovered a transient X-ray source, RX J1420.4+5334, which displays
a ROSAT flux variation of >150 between the ROSAT All-Sky-Survey in 1990 and a
preceding pointed ROSAT observations in July 1990. Optical observations suggest
a non-active galaxy as the only visible counterpart. We therefore tentatively
identify RX J1420.4+5334 as a tidal disruption event in a non-active galaxy.

</DOC>
<DOC>
<DOCNO> 10881 </DOCNO>
Electrical spin injection and detection in a semiconductor. Is it


  The electrical injection of spin polarized electrons in a semiconductor can
be achieved in principle by driving a current from a ferromagnetic metal, where
current is known to be significantly spin polarized, into the semiconductor via
ohmic conduction. For detection a second ferromagnet can be used as drain. We
studied submicron lateral spin valve junctions, based on high mobility
InAs/AlSb two-dimensional electron gas (2DEG), with Ni, Co and Permalloy as
ferromagnetic electrodes. In the standard geometry it is very difficult to
separate true spin injection from other effects, including local Hall effect,
anomalous magnetoresistance (AMR) contribution from the ferromagnetic
electrodes and weak localization/anti-localization corrections, which can
closely mimic the signal expected from spin valve effect. The reduction in
size, and the use of a multiterminal non-local geometry allowed us to reduce
the unwanted effects to a minimum. Despite all our efforts, we have not been
able to observe spin injection. However, we find that this 'negative' result in
these systems is actually consistent with theoretical predictions for spin
transport in diffusive systems.

</DOC>
<DOC>
<DOCNO> 117733 </DOCNO>
BeppoSAX and Chandra Observations of SAXJ0103.2-7209=2E0101.5-7225: a


  We report the results of a 1998 July BeppoSAX observation of a field in the
SMC which led to the discovery of 345s pulsations in the X-ray flux of
SAXJ0103.2-7209. The BeppoSAX X-ray spectrum is well fit by an absorbed
power-law with photon index 1.0 plus a black body component with kT=0.1keV. The
unabsorbed luminosity in the 2-10 keV energy range is 1.2x10^{36} erg/s. In a
very recent Chandra observation the 345s pulsations are also detected. The
available period measurements provide a constant period derivative of -1.7s/yr
over the last three years making SAXJ0103.2-7209 one of the most rapidly
spinning-up X-ray pulsars known. The BeppoSAX position is consistent with that
of the Einstein source 2E0101.5-7225 and the ROSAT source RXJ0103.2-7209. This
source was detected at a luminosity level of few 10^{35}-10^{36} erg/s in all
datasets of past X-ray missions since 1979. The ROSAT HRI and Chandra positions
are consistent with that of a m_V=14.8 Be spectral type star already proposed
as the likely optical counterpart of 2E0101.5-7225. We conclude that
SAXJ0103.2-7209 and 2E0101.5-7225 are the same source, a relatively young and
persistent X-ray pulsar in the SMC.

</DOC>
<DOC>
<DOCNO> 101919 </DOCNO>
Spherically symmetrical configurations of self-dual Yang-Mills and


  Spherically symmetrical reductions of self-dual Yang-Mills and
Einstein-Plebanski equations are constructed at the same manner. As in the
first case we come back to known before solutions (under such kind of reduction
but in some different form) if in the second one we obtain unknown before
equation describing the spherically symmetrical configurations of Plebanski
equation and some number of its particular solutions.

</DOC>
<DOC>
<DOCNO> 80713 </DOCNO>
Gauge Field Theory Coherent States (GCS) : III. Ehrenfest Theorems


  In the preceding paper of this series of articles we established peakedness
properties of a family of coherent states that were introduced by Hall for any
compact gauge group and were later generalized to gauge field theory by
Ashtekar, Lewandowski, Marolf, Mour\~ao and Thiemann.
  In this paper we establish the ``Ehrenfest Property'' of these states which
are labelled by a point (A,E), a connection and an electric field, in the
classical phase space. By this we mean that i) The expectation value of {\it
all} elementary quantum operators $\hat{O}$ with respect to the coherent state
with label (A,E) is given to zeroth order in $\hbar$ by the value of the
corresponding classical function O evaluated at the phase space point (A,E) and
ii) The expectation value of the commutator between two elementary quantum
operators $[\hat{O}_1,\hat{O}_2]/(i\hbar)$ divided by $i\hbar$ with respect to
the coherent state with label (A,E) is given to zeroth order in $\hbar$ by the
value of the Poisson bracket between the corresponding classical functions
$\{O_1,O_2\}$ evaluated at the phase space point (A,E).
  These results can be extended to all polynomials of elementary operators and
to a certain non-polynomial function of the elementary operators associated
with the volume operator of quantum general relativity. It follows that the
infinitesimal quantum dynamics of quantum general relativity is to zeroth order
in $\hbar$ indeed given by classical general relativity.

</DOC>
<DOC>
<DOCNO> 121194 </DOCNO>
The interplay of observational errors through numerical simulations


  White dwarf cooling sequences provides a useful indicator of the evolutionary
time scales involved in the chronometry and star formation history of the
galactic disk and, for this reason, the luminosity function of white dwarfs has
become a powerful tool for studies of the evolution and formation of the Milky
Way.
  We examine the faint-end ($M_V > +14$) behavior of the disk white dwarf
luminosity function using the $1/V_{\rm max}$ method, but, for the first time,
fully including the effects of realistic observational errors in the derived
luminosity function.
  We find that observational errors, mostly in the bolometric corrections and
trigonometric parallaxes, play a major role in obliterating (real or
artificial) small scale fluctuations in the luminosity function. A better
estimator of the true luminosity function seems to be the median over
simulations, rather than the mean. When using the latter, an age of 10 Gyr or
older can not be ruled out from the sample of Leggett, Ruiz, and Bergeron
(1998).

</DOC>
<DOC>
<DOCNO> 102093 </DOCNO>
An Operator Hilbert space without the operator approximation property


  We use a technique of Szankowski to construct an operator Hilbert space that
does not have the operator approximation property

</DOC>
<DOC>
<DOCNO> 11204 </DOCNO>
Fermionic long range correlations realized by particles obeying deformed


  Deformed exchange statistics is realized in terms of electronic operators.
This is employed to rewrite Hubbard type lattice models for particles obeying
deformed statistics (we refer to them as deformed models) as lattice models for
electrons. The resulting models show up gauge--like modulations in the hopping
processes, which induce long-range correlations in the lattice. The conditions
for the Bethe ansatz solvability of the latter are interpreted as restrictions
imposed on the statistics to be compatible with the Bethe ansatz solvability of
the deformed models. It is found that solvable deformed models are not
unitarily equivalent to fermionic models if the exchange of particles with the
same spin-orientations is deformed. Statistics deformations, where the exchange
relation of two particles is influenced by the presence of other particles,
cannot be realized by fermionic operators.

</DOC>
<DOC>
<DOCNO> 116509 </DOCNO>
Characterization of a high-power tapered semiconductor amplifier system


  We have characterized a semiconductor amplifier laser system which provides
up to 200mW output after a single-mode optical fiber at 780nm wavelength. The
system is based on a tapered semiconductor gain element, which amplifies the
output of a narrow-linewidth diode laser. Gain and saturation are discussed as
a function of operating temperature and injection current. The spectral
properties of the amplifier are investigated with a grating spectrometer.
Amplified spontaneous emission (ASE) causes a spectral background with a width
of 4nm FWHM. The ASE background was suppressed to below our detection limit by
a proper choice of operating current and temperature, and by sending the light
through a single-mode optical fiber. The final ASE spectral density was less
than 0.1nW/MHz, i.e. less than 0.2 % of the optical power. Related to an
optical transition linewidth of $\Gamma/2\pi=6$ MHz for rubidium, this gives a
background suppression of better than -82dB. An indication of the beam quality
is provided by the fiber coupling efficiency up to 59 %. The application of the
amplifier system as a laser source for atom optical experiments is discussed.

</DOC>
<DOC>
<DOCNO> 67914 </DOCNO>
Discrete Symmetries (C,P,T) in Noncommutative Field Theories


  In this paper we study the invariance of the noncmmutative gauge theories
under C, P and T transformations. For the noncommutative space (when only the
spatial part of $\theta$ is non-zero) we show that NCQED is Parity invariant.
In addition, we show that under charge conjugation the theory on noncommutative
$R^4_{\theta}$ is transformed to the theory on $R^4_{-\theta}$, so NCQED is a
CP violating theory. The theory remains invariant under time reversal if,
together with proper changes in fields, we also change $\theta$ by $-\theta$.
Hence altogether NCQED is CPT invariant. Moreover we show that the CPT
invariance holds for general noncommutative space-time.

</DOC>
<DOC>
<DOCNO> 117842 </DOCNO>
Quasar Candidate Multicolor Selection Technique: a different approach


  We present a quasar candidate identification technique based on multicolor
photometry. The traditional multi-dimensional method (2 $\times$ N dimensions,
where N is the number of the color-color diagrams) is reduced to a
one-dimensional technique, which consists in a standard fitting procedure,
where the observed spectral energy distributions are compared to quasar
simulated spectra and stellar templates. This new multicolor approach is
firstly applied to simulated catalogues and its {\it efficiency} is examined in
various redshift ranges, as a function of the filter combination and the
available observing time for spectroscopy. We conclude that this method is
better suited than the usual multicolor selection techniques to quasar
identification, especially for high-redshift quasars. The application of the
method to real quasar samples found in the literature results in an {\it
efficiency} comparable to the one obtained from the use of color-color
diagrams. The major advantage of the new method is the estimation of the {\it
photometric} redshift of quasar candidates, enabling, in almost all cases,
spectroscopy to be targeted to best suited wavelength ranges.

</DOC>
<DOC>
<DOCNO> 13334 </DOCNO>
From Minority Games to real markets


  We address the question of market efficiency using the Minority Game (MG)
model. First we show that removing unrealistic features of the MG leads to
models which reproduce a scaling behavior close to what is observed in real
markets. In particular we find that i) fat tails and clustered volatility arise
at the phase transition point and that ii) the crossover to random walk
behavior of prices is a finite size effect. This, on one hand, suggests that
markets operate close to criticality, where the market is marginally efficient.
On the other it allows one to measure the distance from criticality of real
market, using cross-over times. The artificial market described by the MG is
then studied as an ecosystem with different_species_ of traders. This clarifies
the nature of the interaction and the particular role played by the various
populations.

</DOC>
<DOC>
<DOCNO> 11431 </DOCNO>
Quasiparticles and Vortices in Unconventional Superconductors


  Quasiparticles in the vortex lattice of strongly type-II superconductors are
investigated by means of a singular gauge transformation applied to the tight
binding lattice Bogoliubov-de Gennes Hamiltonian. We present a detailed
derivation of the gauge invariant effective low energy Hamiltonian for the
quasiparticle-vortex system and show how the physics of the "Doppler shift" and
"Berry phase" can be incorporated at the Hamiltonian level by working in the
singular gauge. In particular, we show that the "Berry phase" effect manifests
itself in the effective Hamiltonian through a half-flux Aharonov-Bohm
scattering of quasiparticles off vortices and stress the important role that
this effect plays in the quasiparticle dynamics. Full numerical solutions in
the regime of intermediate fields H_c1<<B<<H_c2 are presented for model
superconductors with s-, p- and d-wave symmetries and with square and
triangular vortex lattices. For s- and p-wave cases we obtain low energy bound
states in the core, in agreement with the existing results. For d-wave case
only extended quasiparticle states exist. We investigate in detail the nature
of these extended states and provide comparison to the previous results within
linearized ``Dirac fermion'' model. We also investigate internodal interference
effects when vortex and ionic lattices have high degree of commensurability and
discuss various specific choices for the singular gauge transformation.

</DOC>
<DOC>
<DOCNO> 122131 </DOCNO>
Kinematics of the ionized gas in the Local Group irregular galaxy IC


  We present Halpha and [SII] observations for the Local Group irregular galaxy
IC 1613 using the PUMA scanning Fabry-Perot interferometer. Our goal is to
analyze the kinematics of the ionized gas in the complex sample of superbubbles
located in the whole extension of our field (10 arcmin), which includes most of
the optical emission of this galaxy, and to study the inter-relationship
between young stellar associations and nebulae based on a previous study that
we have made on the stellar associations of the central region of this galaxy.
The ionized gas in this galaxy is distributed in classical HII regions and in a
series of superbubbles (also called giant shells) covering a large fraction of
the optical extent of the galaxy. We present a catalog of kinematical
properties of both the HII regions of this galaxy and the superbubbles. We have
also compared the kinematics of the ionized gas in HII regions to search for
possible dynamic differences between neutral and ionized gas.

</DOC>
<DOC>
<DOCNO> 13250 </DOCNO>
Elastic Wave Transmission at an Abrupt Junction in a Thin Plate, with


  The transmission coefficient for vibrational waves crossing an abrupt
junction between two thin elastic plates of different widths is calculated.
These calculations are relevant to ballistic phonon thermal transport at low
temperatures in mesoscopic systems and the Q for vibrations in mesoscopic
oscillators. Complete results are calculated in a simple scalar model of the
elastic waves, and results for long wavelength modes are calculated using the
full elasticity theory calculation. We suggest that thin plate elasticty theory
provide a useful and tractable approximation to the full three dimensional
geometry.

</DOC>
<DOC>
<DOCNO> 70184 </DOCNO>
O(alpha_s^5 m) quarkonium 1S spectrum in large-beta_0 approximation and


  Presently the quarkonium spectrum, written in terms of the quark MSbar-mass,
is known at O(alpha_s^3 m) accuracy. We point out that in order to achieve
O(alpha_s^4 m) accuracy it is sufficient to calculate further (I) the
O(alpha_s^4 m) relation between the MSbar-mass and the pole-mass, and (II) the
binding energy at O(alpha_s^5 m) in the large-beta_0 approximation. We
calculate the latter correction analytically for the 1S-state and study its
phenomenological implications.

</DOC>
<DOC>
<DOCNO> 8643 </DOCNO>
O(2) symmetry breaking vs. vortex loop percolation


  We study with lattice Monte Carlo simulations the relation of global O(2)
symmetry breaking in three dimensions to the properties of a geometrically
defined vortex loop network. We find that different definitions of constructing
a network lead to different results even in the thermodynamic limit, and that
with typical definitions the percolation transition does not coincide with the
thermodynamic phase transition. These results show that geometrically defined
percolation observables need not display universal properties related to the
critical behaviour of the system, and do not in general survive in the field
theory limit.

</DOC>
<DOC>
<DOCNO> 11907 </DOCNO>
Transport Anomalies and Marginal Fermi-Liquid Effects at a Quantum


  The conductivity and the tunneling density of states of disordered itinerant
electrons in the vicinity of a ferromagnetic transition at low temperature are
discussed. Critical fluctuations lead to nonanalytic frequency and temperature
dependences that are distinct from the usual long-time tail effects in a
disordered Fermi liquid. The crossover between these two types of behavior is
proposed as an experimental check of recent theories of the quantum
ferromagnetic critical behavior. In addition, the quasiparticle properties at
criticality are shown to be those of a marginal Fermi liquid.

</DOC>
<DOC>
<DOCNO> 122358 </DOCNO>
Supernovae in the nuclear regions of starburst galaxies


  The feasibility of using near-infrared observations to discover supernovae in
the nuclear and circumnuclear regions of nearby starburst galaxies is
investigated. We provide updated estimates of the intrinsic core-collapse
supernova rates in these regions. We discuss the problem of extinction, and
present new estimates of the extinction towards 33 supernova remnants in the
starburst galaxy M 82. This is done using H I and H_2 column density
measurements. We estimate the molecular to atomic hydrogen mass ratio to be 7.4
+- 1.0 in M 82. We have assembled near-infrared photometric data for a total of
13 core-collapse supernovae, some unpublished hitherto. This constitutes the
largest database of IR light curves for such events. We show that the IR light
curves fall into two classes, ``ordinary'' and ``slow-declining''. Template
JHKL light curves are derived for both classes. For ordinary core-collapse
supernovae, the average peak JHKL absolute magnitudes are -18.4, -18.6, -18.6,
and -19.0 respectively. The slow-declining core-collapse SNe are found to be
significantly more luminous than the ordinary events, even at early times,
having average peak JHKL absolute magnitudes of -19.9, -20.0, -20.0, and -20.4
respectively. We investigate the efficiency of a computerised image subtraction
method in supernova detection. We then carry out a Monte Carlo simulation of a
supernova search using K-band images of NGC 5962. The effects of extinction and
observing strategy are discussed. We conclude that a modest observational
programme will be able to discover a number of nuclear supernovae.

</DOC>
<DOC>
<DOCNO> 13577 </DOCNO>
Magnetic Phases of Electron-Doped Manganites


  We study the anisotropic magnetic structures exhibited by electron-doped
manganites using a model which incorporates the double-exchange between orbital
ly degenerate $e_{g}$ electrons and the super-exchange between $t_{2g}$
electrons with realistic values of the Hund's coupling($J_H$), the
super-exchange coupling($J_{AF}$), and the bandwidth($W$). We look at the
relative stabilities of the G, C and A type antiferromagnetic ph ases. In
particular we find that the G-phase is stable for low electron doping as seen
in experiments. We find good agreement with the experimentally observed
magnetic phase diagrams of electron-doped manganites
 ($x > 0.5$) such as Nd$_{1-x}$Sr$_{x}$MnO$_{3}$, Pr$_{1-x}$Sr$_{x}$MnO$_{3}$,
and Sm$_{1-x}$Ca$_{x}$MnO$_{3}$. We can also explain the experimentally
observed orbital structures of the C a nd A phases.
 We also extend our calculation for electron-doped bilayer manganites of the
form R$_{2-2x}$A$_{1+2x}$Mn$_2$O$_7$ and predict that the C-phase will be
absent in t hese systems due to their reduced dimensionality.

</DOC>
<DOC>
<DOCNO> 150792 </DOCNO>
Renormalisability of the SU(2)$\times$U(1) Electroweak Theory with


  We extend the previous work and study the renormalisability of the SU$_L$(2)
$\times$ U$_Y$(1) electroweak theory with massive W Z fields and massive matter
fields. We expound that with the constraint conditions caused by the W Z mass
term and the additional condition chosen by us we can still performed the
quantization in the same way as before. We also show that when the $\delta-$
functions appearing in the path integral of the Green functions and
representing the constraint conditions are rewritten as Fourier integrals with
Lagrange multipliers $\lambda_a$ and $\lambda_y$, the total effective action
consisting of the Lagrange multipliers, ghost fields and the original fields is
BRST invariant. Furthermore, with the help of the the renormalisability of the
theory without the the mass term of matter fields, we find the general form of
the divergent part of the generating functional for the regular vertex
functions and prove the renormalisability of the theory with the mass terms of
the W Z fields and the matter fields.

</DOC>
<DOC>
<DOCNO> 120425 </DOCNO>
Fluctuations in the Radio Background from Intergalactic Synchrotron


  The shocks produced in the intergalactic medium during large-scale structure
formation accelerate a population of highly relativistic electrons which emit
synchrotron radiation due to intergalactic magnetic fields. In a previous paper
(Loeb & Waxman 2000) we have shown that these electrons cool primarily by
inverse-Compton scattering of the microwave background photons and can thereby
produce the observed intensity and spectrum of the diffuse gamma-ray
background. Here we calculate the intensity and angular fluctuations of the
radio synchrotron background that results from the same high-energy electrons,
as well as the expected angular fluctuations in the gamma-ray background. On
angular scales smaller than a degree, the predicted fluctuations in the
microwave background temperature are of order 40micro-K*(xi_B/0.01)(nu/10
GHz)^{-3}, where xi_B is the magnetic fraction of the post-shock energy
density. This foreground might have already dominated the anisotropy signal
detected in existing low-frequency CMB experiments, and can be identified with
confidence through multi-frequency observations. Detection of the synchrotron
fluctuations would allow to determine the strength of the intergalactic
magnetic field. We predict a strong correlation between high-resolution maps
taken at low-frequency radio waves and at high-energy gamma-rays. Young X-ray
clusters may also appear as radio or gamma-ray clusters. The detailed study of
this correlation will become easily accessible with the future launch of GLAST.

</DOC>
<DOC>
<DOCNO> 85625 </DOCNO>
Twistor and "weak" gauge structures in the framework of quaternionic


  The earlier proposed conditions of (bi)quaternionic differentiability are
nonlinear, give rize to the 2-spinor and the self-dual gauge structures and may
be considered as the it generating system of equations (GSE) with respect to
the source-free Maxwell, Yang-Mills and eikonal equations. We present the
general solution of the GSE in terms of twistor variables, analize its rather
specific gauge symmetry and demonstrate the relation of GSE to the equations of
shear-free null congruences and, consequently, - to effective metrics of Kerr-
Shild type. The concept of particles as singularities of physical fields
associated with the solutions of GSE is developed

</DOC>
<DOC>
<DOCNO> 39762 </DOCNO>
The H1 Silicon Vertex Detector


  The design, construction and performance of the H1 silicon vertex detector is
described. It consists of two cylindrical layers of double sided, double metal
silicon sensors read out by a custom designed analog pipeline chip. The analog
signals are transmitted by optical fibers to a custom designed ADC board and
are reduced on PowerPC processors. Details of the design and construction are
given and performance figures from the first data taking periods are presented.

</DOC>
<DOC>
<DOCNO> 169973 </DOCNO>
Quantum decoherence and the Glauber dynamics from the Stochastic limit


  The effects of decoherence for quantum system coupled with a bosonic field
are investigated. An application of the stochastic golden rule shows that in
the stochastic limit the dynamics of such a system is described by a quantum
stochastic differential equation. The corresponding master equation describes
convergence of a system to equilibrium. In particular it predicts exponential
damping for off-diagonal matrix elements of the system density matrix, moreover
these elements for a generic system will decay at least as
\exp(-tN{kT\over\hbar}), where N is a number of particles in the system. As an
application of the described technique a derivation from first principles (i.e.
starting from a Hamiltonian description) of a quantum extension of the Glauber
dynamics for systems of spins is given.

</DOC>
<DOC>
<DOCNO> 99331 </DOCNO>
Les espaces duaux pour les ensembles ordonn\'es arbitraires


  A duality between general partially ordered sets and certain topolgical
spaces with two closures is established.

</DOC>
<DOC>
<DOCNO> 11154 </DOCNO>
Electron-Phonon Coupling Origin of the resistivity in YNi_{2}B_{2}C


  Resistivity measurements from 4.2 K up to 300 K were made on YNi_{2}B_{2}C
single crystals with Tc=15.5 K. The resulting rho(T) curve shows a perfect
Bloch-Grueneisen (BG) behavior, with a very small residual resistivity which
indicates the low impurity content and the high cristallographic quality of the
samples. The value lambda_{tr}=0.53 for the transport electron-phonon coupling
constant was obtained by using the high-temperature constant value of d(rho)/dT
and the plasma frequency reported in literature. The BG expression for the
phononic part of the resistivity rho_{ph}(T) was then used to fit the data in
the whole temperature range, by approximating alpha^{2}_{tr}F(Omega) with the
experimental phonon spectral density G(Omega) multiplied by a two-step
weighting function to be determined by the fit. The resulting fitting curve
perfectly agrees with the experimental points. We also solved the real-axis
Eliashberg equations in both s- and d-wave symmetries under the approximation
alpha^{2}F(Omega)= alpha^{2}_{tr}F(Omega). We found that the value of
lambda_{tr} here determined in single-band approximation is quite compatible
with Tc and the gap Delta experimentally observed. Finally, we calculated the
normalized tunneling conductance, whose comparison with break-junction tunnel
data gives indication of the possible s-wave symmetry for the order parameter
in YNi_{2}B_{2}C.

</DOC>
<DOC>
<DOCNO> 84793 </DOCNO>
A Gaussian Weave for Kinematical Loop Quantum Gravity


  Remarkable efforts in the study of the semi-classical regime of kinematical
loop quantum gravity are currently underway. In this note, we construct a
``quasi-coherent'' weave state using Gaussian factors. In a similar fashion to
some other proposals, this state is peaked in both the connection and the spin
network basis. However, the state constructed here has the novel feature that,
in the spin network basis, the main contribution for this state is given by the
fundamental representation, independently of the value of the parameter that
regulates the Gaussian width.

</DOC>
<DOC>
<DOCNO> 9192 </DOCNO>
Generating moment equations in the Doi model of liquid-crystalline


  We present a self-consistent method for deriving moment equations for kinetic
models of polymer dynamics. The Doi model [M. Doi, J.Polymer. Sci., Polym.
Phys. Ed. 19, 229 (1981)] of liquid-crystalline polymers with the Onsager
excluded-volume potential is considered as an example. To lowest order, this
method amounts to a simple effective potential different from the Maier-Saupe
form. Analytical results are presented which indicate that this effective
potential provides a better approximation to the Onsager potential than the
Maier-Saupe potential. Corrections to the effective potential are obtained.

</DOC>
<DOC>
<DOCNO> 70725 </DOCNO>
Unitarity and Interfering Resonances in pipi Scattering and in Pion


  Additivity of Breit-Wigner phases has been proposed to describe interfering
resonances in partial waves in $\pi\pi$ scattering. This assumption leads to an
expression for partial wave amplitudes that involves products of Breit-Wigner
amplitudes. We show that this expression is equivalent to a coherent sum of
Breit-Wigner amplitudes with specific complex coefficients which depend on the
resonance parameters of all contributing resonances. We use analyticity of
$\pi\pi$ partial wave amplitudes to show that they must have the form of a
coherent sum of Breit-Wigner amplitudes with complex coefficients and a complex
coherent background. The assumption of additivity of Breit-Wigner phases
restricts the partial waves to analytical functions with very specific form of
residues of Breit-Wigner poles. We argue that the general form provided by the
analyticity is more appropriate in fits to data to determine resonance
parameters. The partial wave unitarity can be imposed using the modern methods
of constrained optimization. We discuss unitarity and the production amplitudes
in $\pi N\to\pi\pi N$ and use analyticity in the dipion mass variable to
justify the common practice of writing the production amplitudes as a coherent
sum of Breit-Wigner amplitudes with free complex coefficients and a complex
coherent background in fits to mass spectra with interfering resonances.

</DOC>
<DOC>
<DOCNO> 69575 </DOCNO>
Low-Energy Limits of Theories With Two Supersymmetries


  Given its non-renormalization properties, low-energy supersymmetry provides
an attractive framework for extending the Standard Model and for resolving the
hierarchy problem. Models with softly broken N =1 supersymmetry were
extensively studied and are phenomenologically successful. However, it could be
that an extended N = 2 supersymmetry survives to low energies, as suggested by
various constructions. We examine the phenomenological viability and
implications of such a scenario. We show that consistent chiral fermion mass
generation emerges in N=2 theories, which are vectorial, as a result of
supersymmetry breaking at low energies. A rich mirror quark and lepton spectrum
near the weak scale with model-dependent decay modes is predicted. A Z_{2}
mirror parity is shown to play an important role in determining the
phenomenology of the models. It leads, if conserved, to a new stable particle,
the LMP. Consistency of the N=2 framework and its unique spectrum with
electroweak precision data is considered, and the discovery potential in the
next generation of hadron collider experiments is stressed. Mirror quark pair
production provides the most promising discovery channel. Higgs searches are
also discussed and it is shown that there is no upper bound on the prediction
for the Higgs boson mass in the framework of low-energy supersymmetry breaking,
in general, and in the N=2 framework, in particular. Possible N = 2
realizations of flavor symmetries and of neutrino masses are also discussed.

</DOC>
<DOC>
<DOCNO> 119080 </DOCNO>
Cosmic Ray Anisotropy Analysis with a Full-Sky Observatory


  A cosmic ray observatory with full-sky coverage can exploit standard
anisotropy analysis methods that do not work if part of the celestial sphere is
never seen. In particular, the distribution of arrival directions can be fully
characterized by a list of spherical harmonic coefficients. The dipole vector
and quadrupole tensor are of special interest, but the full set of harmonic
coefficients constitutes the anisotropy fingerprint that may be needed to
reveal the identity of the cosmic ray sources. The angular power spectrum is a
coordinate-independent synopsis of that fingerprint. The true cosmic ray
anisotropy can be measured despite non-uniformity in celestial exposure,
provided the observatory is not blind to any region of the sky. This paper
examines quantitatively how the accuracy of anisotropy measurement depends on
the number of arrival directions in a data set.

</DOC>
<DOC>
<DOCNO> 152030 </DOCNO>
Chern-Simons Gravity: From 2+1 to 2n+1 Dimensions


  These lectures provide an elementary introduction to Chern Simons Gravity and
Supergravity in $d=2n+1$ dimensions.

</DOC>
<DOC>
<DOCNO> 119992 </DOCNO>
Limits on the cosmic-ray ionization rate toward massive young stars


  Recent models of the envelopes of seven massive protostars are used to
analyze observations of H3+ infrared absorption and H13CO+ submillimeter
emission lines toward these stars, and to constrain the cosmic-ray ionization
rate zeta. The H13CO+ gives best-fit values of zeta=(2.6+/- 1.8) x 10^-17 s^-1,
in good agreement with diffuse cloud models and with recent Voyager/Pioneer
data but factors of up to 7 lower than found from the H3+ data. No relation of
zeta with luminosity or total column density is found, so that local (X-ray)
ionization and shielding against cosmic rays appear unimportant for these
sources. The difference between the H3+ and H13CO+ results and the correlation
of N(H3+) with heliocentric distance suggest that intervening clouds contribute
significantly to the H3+ absorptions in the more distant regions. The most
likely absorbers are low-density (<~10^4 cm^-3) clouds with most carbon in
neutral form or in CO.

</DOC>
<DOC>
<DOCNO> 118750 </DOCNO>
A Characteristic Scale on the Cosmic Microwave Sky


  The current suite of results from Cosmic Microwave Background anisotropy
experiments is fulfilling the promise of providing extraordinary levels of
discrimination between cosmological models. We calculate a binned anisotropy
power spectrum, which we tabulate, along with error bars and bin-to-bin
correlations, so that it can be easily used for constraining models. The
resulting power spectrum is flat at large angles, with a gradual rise to a
prominent peak at around 0.5 degrees and a decrease thereafter. This is
precisely the shape predicted by inflationary-inspired adiabatic models. Within
that class of cosmologies, this characteristic scale imprinted on the CMB sky
can be used to infer that the geometry of the Universe is very close to flat.
The next wave of CMB results should add fuel to the debate about whether or not
the Universe once inflated, as well as beginning in earnest the task of
measuring cosmological parameters.

</DOC>
<DOC>
<DOCNO> 11165 </DOCNO>
Spin-wave spectrum of a two-dimensional itinerant electron system:


  We study the zero-temperature spin fluctuations of a two-dimensional
itinerant-electron system with an incommensurate magnetic ground state
described by a single-band Hubbard Hamiltonian. We introduce the
(broken-symmetry) magnetic phase at the mean-field (Hartree-Fock) level through
a \emph{spiral spin configuration} with characteristic wave vector
$\gmathbf{Q}$ different in general from the antiferromagnetic wave vector
$\gmathbf{Q_{AF}}$, and consider spin fluctuations over and above it within the
electronic random-phase (RPA) approximation. We obtain a \emph{closed} system
of equations for the generalized wave vector and frequency dependent
susceptibilities, which are equivalent to the ones reported recently by Brenig.
We obtain, in addition, analytic results for the spin-wave dispersion relation
in the strong-coupling limit of the Hubbard Hamiltonian and find that at finite
doping the spin-wave dispersion relation has a \emph{hybrid form} between that
associated with the (localized) Heisenberg model and that associated with the
(long-range) RKKY exchange interaction. We also find an instability of the
spin-wave spectrum in a finite region about the center of the Brillouin zone,
which signals a physical instability toward a different spin- or, possibly,
charge-ordered phase, as, for example, the stripe structures observed in the
high-Tc materials. We expect, however, on physical grounds that for wave
vectors external to this region the spin-wave spectrum that we have determined
should survive consideration of more sophisticated mean-field solutions.

</DOC>
<DOC>
<DOCNO> 118855 </DOCNO>
Unusually rapid variability of the GRB000301C optical afterglow


  We present BVRI light curves of the afterglow of GRB000301C, one of the
brightest ever detected at a day time scale interval after GRB trigger. The
monitoring started 1.5 days after the GRB and ended one month later. Inspection
of the extremely well sampled R band light curve and comparison with BVI data
has revealed a complex behavior, with a long term flux decrease and various
short time scale features superimposed. These are uncommon among other observed
afterglows, and might trace either intrinsic variability within the
relativistic shock (re-acceleration and re-energization) or inhomogeneities in
the medium in which the shock propagates.

</DOC>
<DOC>
<DOCNO> 100121 </DOCNO>
There is no tame triangulation of the infinite real Grassmannian


  We show that there is no triangulation of the infinite real Grassmannian of
k-planes in R^\infty which is nicely situated with respect to the coordinate
axes. In terms of matroid theory, this says there is no triangulation of the
Grassmannian subdividing the matroid stratification. This is proved by an
argument in projective geometry, considering a specific sequence of
configurations of points in the plane.

</DOC>
<DOC>
<DOCNO> 119073 </DOCNO>
Multiple Sub-Jet Model of Gamma Ray Bursts and Possible Origin of X-ray


  We assume that internal shocks of Gamma Ray Bursts (GRBs) consist of multiple
sub-jets with a collimation half-angle $\sim {\rm several
}\times\gamma_i^{-1}$, where $\gamma_i$ is the Lorenz factor of each sub-jet.
If by chance a sub-jet is first emitted off-axis from the line of sight, the
observed peak energy can be in the X-ray region. Next if by chance a subsequent
sub-jet is emitted along the line of sight, then the peak energy will be in the
gamma ray region and the gamma ray may arrive after the X-ray precursor from
the former sub-jet depending on parameters. This model predicts a new class of
GRBs with extremely weak and short gamma ray emission but X-ray precursor
and/or post-cursor as well as an afterglow.

</DOC>
<DOC>
<DOCNO> 13748 </DOCNO>
Conservation-laws-preserving algorithms for spin dynamics simulations


  We propose new algorithms for numerical integration of the equations of
motion for classical spin systems with fixed spatial site positions. The
algorithms are derived on the basis of a mid-point scheme in conjunction with
the multiple time staging propagation. Contrary to existing predictor-corrector
and decomposition approaches, the algorithms introduced preserve all the
integrals of motion inherent in the basic equations. As is demonstrated for a
lattice ferromagnet model, the present approach appears to be more efficient
even over the recently developed decomposition method.

</DOC>
<DOC>
<DOCNO> 170160 </DOCNO>
Rigged Hilbert spaces and time-asymmetry: the case of the upside-down


  The upside-down simple harmonic oscillator system is studied in the contexts
of quantum mechanics and classical statistical mechanics. It is shown that in
order to study in a simple manner the creation and decay of a physical system
by ways of Gamow vectors we must formulate the theory in a time-asymmetric
fashion, namely using two different rigged Hilbert spaces to describe states
evolving towards the past and the future. The spaces defined in the contexts of
quantum and classical statistical mechanics are shown to be directly related by
the Wigner function.

</DOC>
<DOC>
<DOCNO> 122816 </DOCNO>
Do relativistic corrections affect microlensing amplification?


  Studies of gravitational microlensing are usually based on the lens equation,
which is valid only to first order in the gravitational constant $G$. However,
the amplification factor of microlensing is a second-order quantity with
respect to $G$. Despite this fact, conventional studies are still based on the
lowest-order lens equation. Then the question naturally arises: Why are these
conventional studies justified? We carefully study the relativistic correction
to the amplification factor at $O(G^2)$. We show that the amplification factor
for each image is corrected. However, the total amplification remains unchanged
at this order.

</DOC>
<DOC>
<DOCNO> 69879 </DOCNO>
Gaugino Mass Dependence of Electron and Neutron Electric Dipole Moments


  Unless squarks and sleptons are in the multi-TeV region or above, CP
violating induced electric dipole moments of elementary particles can pose
significant puzzles for supersymmetric (SUSY) models. We study the
dipole-moment-inducing one-loop amplitudes as a function of the fundamental
SUSY parameters and show that these puzzles are removed if there is a
sufficiently large hierarchy between the gaugino masses and the scalar mass. We
comment on the experimental status of the low gaugino mass scenario.

</DOC>
<DOC>
<DOCNO> 8572 </DOCNO>
Antiferromagnetic Correlations versus Superfluid Density in


  We have performed muon spin relaxation and low field ac-susceptibility
measurements in a series of high quality samples of La_{2-x}Sr_xCuO_4
(x=0.08-0.24) as a function of temperature. Superconductivity is found to
coexist with low temperature spin glass order up to the optimally doped region
where the normal state pseudogap also closes. The systematic depletion of the
superfluid density with the enhancement of aniferromagnetic correlations with
underdoping indicates a competition between antiferromagnetic correlations and
superconductivity.

</DOC>
<DOC>
<DOCNO> 84191 </DOCNO>
Generalized Affine Coherent States: A Natural Framework for Quantization


  Affine variables, which have the virtue of preserving the positive-definite
character of matrix-like objects, have been suggested as replacements for the
canonical variables of standard quantization schemes, especially in the context
of quantum gravity. We develop the kinematics of such variables, discussing
suitable coherent states, their associated resolution of unity, polarizations,
and finally the realization of the coherent-state overlap function in terms of
suitable path-integral formulations.

</DOC>
<DOC>
<DOCNO> 120712 </DOCNO>
Extended line emission around seven radio-loud quasars at redshift z~2


  We present near-infrared spectra of seven radio-loud quasars with a median
redshift of 2.1, five of which were previously known to have Ly alpha nebulae.
Extended [OIII]5007 and H alpha emission are evident around six objects, at the
level of a few times 1E-16 erg/cm^2/arcsec^2/s within 2 arcsec of the nucleus
(16 kpc in the adopted cosmology). Nuclear [OII]3727 is detected in three of
the 5 quasars studied at this wavelength, and clearly extended in one of them.
  The extended [OIII] tends to be brighter on the side of the nucleus with the
stronger, jet-like radio emission, indicating at least that the extranuclear
gas is distributed anisotropically. It is also redshifted by several hundred
km/s from the nuclear [OIII], perhaps because the latter is blueshifted from
the systemic velocity of the host galaxy. Alternatively, the velocity shifts
could be due to infall (which is suggested by line widths ~1000 km/s FWHM) in
combination with a suitable dust geometry. Lyalpha/Halpha ratios well below the
case B value suggest that some dust is present.
  Photoionization modelling of the [OIII]/[OII] ratios in the extended gas
suggests that its pressure is around or less than a few times 1E7 cm^-3 K; any
confining intracluster medium may thus host a strong cooling flow. A comparison
with lower-redshift work suggests that there has been little evolution in the
nuclear emission line properties of radio-loud quasars between redshifts 1 and
2.

</DOC>
<DOC>
<DOCNO> 178747 </DOCNO>
Missing Nucleon Resonances in Kaon Production with Pions and Photons


  Resonances with strong couplings to strangeness channels are investigated in
a coupled-channels framework of kaon production with pions and photons. We find
evidence for an additional D13 resonance around 1900 MeV that has a significant
decay width into the K Lambda final state. Such a state has been predicted in a
relativistic quark model at 1960 MeV with significant gamma N and K Lambda
branching ratios.

</DOC>
<DOC>
<DOCNO> 120724 </DOCNO>
Stellar Mass-to-Light Ratios and the Tully-Fisher relation


  We use spiral galaxy evolution models to argue that there are substantial
variations in stellar mass-to-light ratio (M/L) within and among galaxies. Our
models show a strong correlation between stellar M/L and galaxy color. We
compare the colors and maximum-disk M/L values of a sample of galaxies to the
model color-M/L relation, finding that a Salpeter IMF is too massive but that
an IMF with fewer low mass stars fits the observations well. Applying our
color-M/L relation to the Tully-Fisher (TF) relation, we find a stellar mass
TF-relation that is independent of originating passband. Adding the HI gas
mass, we find that the maximum slope of the baryonic TF-relation is 3.5.

</DOC>
<DOC>
<DOCNO> 13120 </DOCNO>
Superconductivity in the Kondo lattice: a mean-field approach


  We calculate the superconducting critical temperature T_c and the Kondo
temperature T_K of the Kondo lattice, decoupling the Kondo exchange interaction
in the unrestricted Hartree-Fock (HF) Bardeen-Cooper-Schrieffer (BCS)
approximation. We obtain that both T_K and T_c have an exponential dependence
in the Kondo coupling J_K. For optimum doping and realistic parameters, both
temperatures fall in the experimentally observed range.

</DOC>
<DOC>
<DOCNO> 72231 </DOCNO>
The Superspace WZNW Action for 4D, N=1 Supersymmetric QCD


  We discuss features of the 4D, N = 1 WZNW term expressed as a function of
chiral superfields and defined in a manner appropriate to calculate
phenomenological matrix elements.

</DOC>
<DOC>
<DOCNO> 8098 </DOCNO>
Strong Coupling Approach to the Supersymmetric Kondo Model


  We carry out the strong coupling expansion for the SU(N) Kondo model where
the impurity spin is represented by a L-shaped Young tableau. Using second
order perturbation theory around the strong coupling fixed point it is shown
that when the antisymmetric component of the Young-tableau contains more than
N/2 entries, the strong-coupling fixed point becomes unstable to a two-stage
Kondo effect. By comparing the strong coupling results obtained here with the
result using a supersymmetric large N expansion, we are also able to confirm
the validity of the the supersymmetric formalism for mixed symmetry Kondo
models.

</DOC>
<DOC>
<DOCNO> 152173 </DOCNO>
Global conformal anomaly in N=2 string


  We show the existence of a global anomaly in the one-loop graphs of N=2
string theory, defined by sewing tree amplitudes, unless spacetime
supersymmetry is imposed. The anomaly is responsible for the non-vanishing
maximally helicity violating amplitudes. The supersymmetric completion of the
N=2 string spectrum is formulated by extending the previous cohomological
analysis with an external spin factor; the target space-time spin-statistics of
these individual fields in a selfdual background are compatible with previous
cohomological analysis as fields of arbitrary spin may be bosonized into one
another. We further analyze duality relations between the open and closed
string amplitudes and demonstrate this in the supersymmetric extension of the
target space-time theory through the insertion of zero-momentum operators.

</DOC>
<DOC>
<DOCNO> 9248 </DOCNO>
Equilibrium and dynamical properties of the ANNNI chain at the


  We study the equilibrium and dynamical properties of the ANNNI (axial
next-nearest-neighbor Ising) chain at the multiphase point. An interesting
property of the system is the macroscopic degeneracy of the ground state
leading to finite zero-temperature entropy. In our equilibrium study we
consider the effect of softening the spins. We show that the degeneracy of the
ground state is lifted and there is a qualitative change in the low temperature
behaviour of the system with a well defined low temperature peak of the
specific heat that carries the thermodynamic ``weight'' of the ground state
entropy. In our study of the dynamical properties, the stochastic Kawasaki
dynamics is considered. The Fokker-Planck operator for the process corresponds
to a quantum spin Hamiltonian similar to the Heisenberg ferromagnet but with
constraints on allowed states. This leads to a number of differences in its
properties which are obtained through exact numerical diagonalization,
simulations and by obtaining various analytic bounds.

</DOC>
<DOC>
<DOCNO> 10660 </DOCNO>
Regimes of quantum degeneracy in trapped 1D gases


  We discuss the regimes of quantum degeneracy in a trapped 1D gas and obtain
the diagram of states. Three regimes have been identified: the BEC regimes of a
true condensate and quasicondensate, and the regime of a trapped gas of Tonks
(gas of impenetrable bosons). The presence of a sharp cross-over to the BEC
regime requires extremely small interaction between particles. We discuss how
to distinguish between true and quasicondensates in phase coherence
experiments.

</DOC>
<DOC>
<DOCNO> 151571 </DOCNO>
More on generalized simplicial chiral models


  By generalizing the auxiliary field term in the Lagrangian of simplicial
chiral models on a (d-1)-dimensional simplex, the generalized simplicial chiral
models has been introduced in \c{Ali}. These models can be solved analytically
only in d=0 and d=2 cases at large-N limit. In d=0 case, we calculate the
eigenvalue density function in strong regime and show that the partition
function computed from this density function is consistent with one calculated
by path integration directly. In d=2 case, it is shown that all $V= {\rm
Tr}(AA^{\d})^n$ models have a third order phase transition, same as the
2-dimensional Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 83177 </DOCNO>
Advances in domain independent linear text segmentation


  This paper describes a method for linear text segmentation which is twice as
accurate and over seven times as fast as the state-of-the-art (Reynar, 1998).
Inter-sentence similarity is replaced by rank in the local context. Boundary
locations are discovered by divisive clustering.

</DOC>
<DOC>
<DOCNO> 11585 </DOCNO>
Density fluctuations and the structure of a nonuniform hard sphere fluid


  We derive an exact equation for density changes induced by a general external
field that corrects the hydrostatic approximation where the local value of the
field is adsorbed into a modified chemical potential. Using linear response
theory to relate density changes self-consistently in different regions of
space, we arrive at an integral equation for a hard sphere fluid that is exact
in the limit of a slowly varying field or at low density and reduces to the
accurate Percus-Yevick equation for a hard core field. This and related
equations give accurate results for a wide variety of fields.

</DOC>
<DOC>
<DOCNO> 99638 </DOCNO>
Geometric variational problems of statistical mechanics and of


  We present the geometric solutions of the various extremal problems of
statistical mechanics and combinatorics. Together with the Wulff construction,
which predicts the shape of the crystals, we discuss the construction which
exhibits the shape of a typical Young diagram and of a typical skyscraper.

</DOC>
<DOC>
<DOCNO> 99454 </DOCNO>
Solutions Near Singular Points to the Eikonal and Related First Order


  A detailed study of solutions to the first order partial differential
equation H(x,y,z_x,z_y)=0, with special emphasis on the eikonal equation
z_x^2+z_y^2=h(x,y), is made near points where the equation becomes singular in
the sense that dH=0, in which case the method of characteristics does not
apply. The main results are that there is a strong lack of uniqueness of
solutions near such points and that solutions can be less regular than both the
function H and the initial data of the problem, but that this loss of
regularity only occurs along a pair of curves through the singular point. The
main tools are symplectic geometry and the Sternberg normal form for
Hamiltonian vector fields.

</DOC>
<DOC>
<DOCNO> 68255 </DOCNO>
Long-distance effects in $B\to V\gamma$ radiative weak decays


  A systematic approach to long-distance effects in exclusive radiative weak
$B$ decays is presented, based on a combination of the heavy quark limit with
perturbative QCD. The dominant long-distance effects, connected with weak
annihilation and $W$-exchange topologies, can be computed in a
model-independent way using experimental data on $B$ radiative leptonic decays.
Nonfactorizable corrections vanish in the chiral limit and to leading twist.
The left-handed photon amplitudes are shown to be enhanced relative to the
right-handed ones, both in the long- and short-distance parts of the $\bar B$
decay amplitudes. We discuss the implications of our results for the extraction
of $|V_{td}|$.

</DOC>
<DOC>
<DOCNO> 150928 </DOCNO>
Bosons Doubling


  It is shown that next-nearest-neighbor interactions may lead to unusual
paramagnetic or ferromagnetic phases which physical content is radically
different from the standard phases. Actually there are several particles
described by the same quantum field in a manner similar to the species doubling
of the lattice fermions. We prove the renormalizability of the theory at the
one loop level.

</DOC>
<DOC>
<DOCNO> 101602 </DOCNO>
Syzygies of Oriented Matroids


  We construct minimal cellular resolutions of squarefree monomial ideals
arising from hyperplane arrangements, matroids and oriented matroids. These are
Stanley-Reisner ideals of complexes of independent sets, and of triangulations
of Lawrence matroid polytopes. Our resolution provides a cellular realization
of Stanley's formula for their Betti numbers. For unimodular matroids our
resolutions are related to hyperplane arrangements on tori, and we recover the
resolutions constructed by Bayer, Popescu and Sturmfels. We resolve the
combinatorial problems posed in their paper by computing Mobius invariants of
graphic and cographic arrangements in terms of Hermite polynomials.

</DOC>
<DOC>
<DOCNO> 99841 </DOCNO>
Long Range Scattering and Modified Wave Operators for some Hartree Type


  We study the theory of scattering for a class of Hartree type equations with
long range interactions in arbitrary space dimension n > or = 1, including the
case of Hartree equations with time dependent potential V(t,x) = kappa t^(mu -
gamma) |x|^{- mu} with 0 < gamma < or =1 and 0 < mu < n.This includes the case
of potential V(x) = kappa |x|^(-gamma) and can be extended to the limiting case
of nonlinear Schr"odinger equations with cubic nonlinearity kappa t^(n- gamma)
u|u|^2.Using Gevrey spaces of asymptotic states and solutions,we prove the
existence of modified local wave operators at infinity with no size restriction
on the data and we determine the asymptotic behaviour in time of solutions in
the range of the wave operators,thereby extending the results of previous
papers (math.AP/9807031 and math.AP/9903073) which covered the range 0 < gamma
< or = 1, but only 0 < mu < or = n-2, and were therefore restricted to space
dimension n>2.

</DOC>
<DOC>
<DOCNO> 83464 </DOCNO>
Optimal Bidding Algorithms Against Cheating in Multiple-Object Auctions


  This paper studies some basic problems in a multiple-object auction model
using methodologies from theoretical computer science. We are especially
concerned with situations where an adversary bidder knows the bidding
algorithms of all the other bidders. In the two-bidder case, we derive an
optimal randomized bidding algorithm, by which the disadvantaged bidder can
procure at least half of the auction objects despite the adversary's a priori
knowledge of his algorithm. In the general $k$-bidder case, if the number of
objects is a multiple of $k$, an optimal randomized bidding algorithm is found.
If the $k-1$ disadvantaged bidders employ that same algorithm, each of them can
obtain at least $1/k$ of the objects regardless of the bidding algorithm the
adversary uses. These two algorithms are based on closed-form solutions to
certain multivariate probability distributions. In situations where a
closed-form solution cannot be obtained, we study a restricted class of bidding
algorithms as an approximation to desired optimal algorithms.

</DOC>
<DOC>
<DOCNO> 72284 </DOCNO>
Split Multiplets, Coupling Unification and Extra Dimension


  We study a gauge coupling unification scenario based on a non-supersymmetric
5-dimensional model. Through an orbifold compactification, we obtain the
Standard Model with split multiplets on a 4-dimensional wall, which is
compatible with a grand unification.

</DOC>
<DOC>
<DOCNO> 100089 </DOCNO>
Multiplier Ideals of Monomial Ideals


  In this note we calculate the multiplier ideal associated to an arbitrary
monomial ideal in C^n. We discuss applications to the calculation of log
canonical thresholds.

</DOC>
<DOC>
<DOCNO> 71566 </DOCNO>
Short Range Linear Potential in 3D Lattice Compact QED


  We study the static potential between electric charges in the finite
temperature three dimensional compact gauge theory on the lattice. We show that
in the deconfinement phase at small separations between the charges the
potential contains a linearly rising piece which goes over into the Coulomb
potential as the distance between the charges is increased. The linear
potential is due to the gas of magnetic dipoles which are realized as
monopole-antimonopole bound states.

</DOC>
<DOC>
<DOCNO> 84881 </DOCNO>
Regular Magnetic Black Holes and Monopoles from Nonlinear


  It is shown that general relativity coupled to nonlinear electrodynamics
(NED) with the Lagrangian $L(F)$, $F = F_mn F^mn$ having a correct weak field
limit, leads to nontrivial static, spherically symmetric solutions with a
globally regular metric if and only if the electric charge is zero and $L(F)$
tends to a finite limit as $F \to \infty$. Properties and examples of such
solutions, which include magnetic black holes and soliton-like objects
(monopoles), are discussed. Magnetic solutions are compared with their electric
counterparts. A duality between solutions of different theories specified in
two alternative formulations of NED (called $FP$ duality) is used as a tool for
this comparison.

</DOC>
<DOC>
<DOCNO> 70222 </DOCNO>
Single superpartner production at Tevatron Run II


  We study the single productions of supersymmetric particles at Tevatron Run
II which occur in the $2 \to 2-body$ processes involving R-parity violating
couplings of type $\l'_{ijk} L_i Q_j D_k^c$. We focus on the single gaugino
productions which receive contributions from the resonant slepton productions.
We first calculate the amplitudes of the single gaugino productions. Then we
perform analyses of the single gaugino productions based on the three charged
leptons and like sign dilepton signatures. These analyses allow to probe
supersymmetric particles masses beyond the present experimental limits, and
many of the $\l'_{ijk}$ coupling constants down to values smaller than the
low-energy bounds. Finally, we show that the studies of the single gaugino
productions offer the opportunity to reconstruct the $\tilde \chi^0_1$, $\tilde
\chi^{\pm}_1$, $\tilde \nu_L$ and $\tilde l^{\pm}_L$ masses with a good
accuracy in a model independent way.

</DOC>
<DOC>
<DOCNO> 170150 </DOCNO>
Self-Consistent Effective Action for Quantum Particle with


  We calculate the quantum corrections to the classical action of a particle
with coordinate-dependent mass. The result is made self-consistent by a
variational approach, thus making it applicable to strong-couplings and
singular potentials. By including thermal fluctuations, the we obtain an
effective action whose classical Euler-Lagrange equation describes the motion
of a particle including quantum and thermal effects.

</DOC>
<DOC>
<DOCNO> 12230 </DOCNO>
Tilt Modulus and Angle-Dependent Flux Lattice Melting in the Lowest


  For a clean high-T$_c$ superconductor, we analyze the Lawrence-Doniach free
energy in a tilted magnetic field within the lowest Landau level (LLL)
approximation. The free energy maps onto that of a strictly $c$-axis field, but
with a reduced interlayer coupling. We use this result to calculate the tilt
modulus $C_{44}$ of a vortex lattice and vortex liquid. The vortex contribution
to $C_{44}$ can be expressed in terms of the squared $c$-axis Josephson plasmon
frequency $\omega_{pl}^2$. The transverse component of the field has very
little effect on the position of the melting curve.

</DOC>
<DOC>
<DOCNO> 68433 </DOCNO>
Observing Quark-Gluon Plasma with Strange Hadrons


  We review the methods and results obtained in an analysis of the experimental
heavy ion collision research program at nuclear beam energy of 160-200A GeV. We
study strange, and more generally, hadronic particle production experimental
data. We discuss present expectations concerning how these observables will
perform at other collision energies. We also present the dynamical theory of
strangeness production and apply it to show that it agrees with available
experimental results. We describe strange hadron production from the
baryon-poor quark-gluon phase formed at much higher reaction energies, where
the abundance of strange baryons and antibaryons exceeds that of nonstrange
baryons and antibaryons.

</DOC>
<DOC>
<DOCNO> 117422 </DOCNO>
The X-ray/submillimetre link


  It is widely believed that most of the cosmic X-ray background (XRB) is
produced by a vast, hitherto undetected population of obscured AGN. Deep X-ray
surveys with Chandra and XMM will soon test this hypothesis. Similarly, recent
sub-mm surveys with SCUBA have revealed an analogous population of
exceptionally luminous, dust-enshrouded {\em star-forming} galaxies at high
redshift. There is now growing evidence for an intimate link between these
obscured populations. There are currently large uncertainties in the models,
but several independent arguments lead to the conclusion that a significant
fraction of the SCUBA sources ($10-30% $) will contain quasars. Recent
observational studies of SCUBA survey sources appear to confirm these
predictions, although the relative roles of AGN and star-forming activity in
heating the dust are unclear. Forthcoming surveys combining X-ray and sub-mm
observations will provide a very powerful tool for disentangling these
processes.

</DOC>
<DOC>
<DOCNO> 169777 </DOCNO>
On a quantum version of Shannon's conditional entropy


  In this article we propose a quantum version of Shannon's conditional
entropy. Given two density matrices $\rho$ and $\sigma$ on a finite dimensional
Hilbert space and with $S(\rho)=-\tr\rho\ln\rho$ being the usual von Neumann
entropy, this quantity $S(\rho|\sigma)$ is concave in $\rho$ and satisfies
$0\le S(\rho|\sigma)\le S(\rho)$, a quantum analogue of Shannon's famous
inequality. Thus we view $S(\rho|\sigma)$ as the entropy of $\rho$ conditioned
by $\sigma$.

</DOC>
<DOC>
<DOCNO> 117023 </DOCNO>
Higher Dipole Bands in the NLC Accelerating Structure


  We show that scattering matrix calculations for dipole modes between 23-43
GHz for the 206 cell detuned structure (DS) are consistent with finite element
calculations and results of the uncoupled model. In particular, the rms sum
wake for these bands is comparable to that of the first dipole band.
  We also show that for RDDS1 uncoupled wakefield calculations for higher bands
are consistent with measurements. In particular, a clear 26 GHz signal in the
short range wake is found in both results.

</DOC>
<DOC>
<DOCNO> 72054 </DOCNO>
Constraining Dark Matter candidates from structure formation


  We show that collisional damping of adiabatic primordial fluctuations yields
constraints on the possible range of mass and interaction rates of Dark Matter
particles. Our analysis relies on a general classification of Dark Matter
candidates, that we establish independently of any specific particle theory or
model. From a relation between the collisional damping scale and the Dark
Matter interaction rate, we find that Dark Matter candidates must have
cross-sections at decoupling smaller than $ 10^{-33} \frac{m_{dm}}{1 MeV} cm^2$
with photons and $10^{-37} \frac{m_{dm}}{1 MeV} cm^2$ with neutrinos, to
explain the observed primordial structures of $10^9$ Solar mass. These damping
constraints are particularly relevant for Warm Dark Matter candidates. They
also leave open less known regions of parameter space corresponding to
particles having rather high interaction rates with other species than
neutrinos and photons.

</DOC>
<DOC>
<DOCNO> 118107 </DOCNO>
The ages of quasar host galaxies


  We present the results of fitting deep off-nuclear optical spectroscopy of
radio-quiet quasars, radio-loud quasars and radio galaxies at z ~ 0.2 with
evolutionary synthesis models of galaxy evolution. Our aim was to determine the
age of the dynamically dominant stellar populations in the hos t galaxies of
these three classes of powerful AGN. Some of our spectra display residual
nuclear contamination at the shortest wavelengths, but the detailed quality of
the fits longward of the 4000A break provide unequivocal proof, if further
proof were needed, that quasars lie in massive galaxies with (at least at z ~
0.2) evolved stellar populations. By fitting a two-component model we have
separated the very blue (starburst and/or AGN contamination) from the redder
underlying spectral energy distribution, and find that the hosts of all three
classes of AGN are dominated by old stars of age 8 - 14 Gyr. If the blue
component is attributed to young stars, we find that, at most, 1% of the
baryonic mass of these galaxies is involved in star-formation activity at the
epoch of observation. These results strongly support the conclusion reached by
McLure et al. (1999) that the host galaxies of luminous quasars are massive
ellipticals which formed prior to the peak epoch of quasar activity at z ~ 2.5.

</DOC>
<DOC>
<DOCNO> 118444 </DOCNO>
VLA Polarimetry of Two Extended Radio Galaxies


  Multi-wavelength VLA observations of two extended radio galaxies, 0235-197
and 1203+043 are presented. There is some evidence from earlier studies that
these two sources exhibit low frequency (<1 GHz) variability. This work shows
that both sources have linear polarizations, if any, below the detection limits
at 320 MHz, so we cannot explain the variability as being due to instrumental
polarization effects as has been suggested for 3C159. Refractive scintillation
may be the cause of the variability in 0235-197. This would require the
existence of a bright, compact component in one of the hot spots seen in these
observations. This is not implausible but the resolution of this observational
program is insufficent to address that question. The radio source 1203+043
lacks any bright compact component thereby ruling out a refractive
scintillation mechanism for its variability. Consequently, it is possible that
claims of variability in this source are spurious. However, the 320 MHz VLA
observations show that 1203+043 has an `X'-shaped radio structure. This is a
rare morphology for the brightness distribution of a radio galaxy; the
implications of this are examined.

</DOC>
<DOC>
<DOCNO> 8624 </DOCNO>
Ultrafast optical nonlinearity in quasi-one-dimensional Mott-insulator


  We report strong instantaneous photoinduced absorption (PA) in the
quasi-one-dimensional Mott insulator ${\rm Sr_2CuO_3}$ in the IR spectral
region. The observed PA is to an even-parity two-photon state that occurs
immediately above the absorption edge. Theoretical calculations based on a
two-band extended Hubbard model explains the experimental features and
indicates that the strong two-photon absorption is due to a very large
dipole-coupling between nearly degenerate one- and two-photon states. Room
temperature picosecond recovery of the optical transparency suggests the strong
potential of ${\rm Sr_2CuO_3}$ for all-optical switching.

</DOC>
<DOC>
<DOCNO> 117414 </DOCNO>
Emission Lines in the Spectrum of the 3He Star 3 Cen A


  Emission in the 4d - 4f transitions of MnII (multiplet 13, 6122-6132 Ang), in
the 4f - 6g transitions of PII, and in 6149.5 Ang of HgII has been detected in
the spectrum of the helium weak star 3 Centauri A (B5 III-IVp). Weaker emission
from the same MnII multiplet is also seen in the hot, mild HgMn star 46 Aquila
(B9 III).It is suggested that the emission is of photospheric origin and may be
evidence for the stratification of manganese, phosphorus and mercury in the
photosphere of 3 CenA, and of manganese in 46Aql.

</DOC>
<DOC>
<DOCNO> 8052 </DOCNO>
Strong compensation of the quantum fluctuation corrections in clean


  The theory of fluctuation conductivity for an arbitrary impurity
concentration including ultra-clean limit is developed. It is demonstrated that
the formal divergency of the fluctuation density of states contribution
obtained previously for the clean case is removed by the correct treatment of
the non-local ballistic electron scattering. We show that in the ultra-clean
limit ($T\tau \gg \sqrt{\frac{T_c}{T-T_c}}$) the density-of-states quantum
corrections are canceled by the Maki-Thompson term and only quasi-classical
paraconductivity remains.

</DOC>
<DOC>
<DOCNO> 40439 </DOCNO>
Investigation of the Decay of Orbitally-Excited B Mesons and First


  From about 4 million hadronic Z decays recorded by the OPAL detector on and
near to the Z resonance, we select a sample of more than 570000 inclusively
reconstructed B mesons. Orbitally-excited mesons B*J are reconstructed using
Bpi+- combinations. Independently, B* mesons are reconstructed using the decay
B* -> Bgamma. The selected B* candidates are used to obtain samples enriched or
depleted in the decay B*J -> B*pi+-(X), where (X) refers to decay modes with or
without additional accompanying decay particles. From the number of signal
candidates in the Bpi+- mass spectra of these two samples, we perform the first
measurement of the branching ratio of orbitally-excited B mesons decaying into
B*pi(X):
  BR(B*J ->B*pi(X)) = 0.85 +0.36-0.37 +- 0.12, where the first error is
statistical and the second systematic. If B*J decay modes other than single
pion transitions can be neglected the measured ratio corresponds to the
branching ratio BR(B*J->B*pi). In the framework of Heavy Quark Symmetry, a
simultaneous fit to the Bpi+- mass spectra of the samples enriched or depleted
in B*J->B*pi+-(X) decays yields the mass and the width of the B1(3/2) state, as
well as the branching ratio of B*J mesons decaying into B*pi: M(B1(3/2)) =
(5.738 +0.005-0.006 +-0.007) GeV/c2 G(B1(3/2)) = (18 +15-13 +29-23) MeV/c
BR(B*J->B*pi) = 0.74 +0.12-0.10 +0.21-0.15, where the uncertainties are
statistical and systematic, respectively.

</DOC>
<DOC>
<DOCNO> 7852 </DOCNO>
Magnetopolaron effects in light reflection and absorption of a


  The light absorption {\cal A} and reflection{\calR} coefficients for a
three-level system in a quantum well (QW) in a strong magnetic field {\bf H},
directed perpendicularly to the QW's plane, have been calculated. The energy
levels correspond to the ground state and to magnetopolaron energy levels
\hbar\omega_{1(2)} with the inverse lifetimes \gamma_{r1(2)} and \gamma_{1(2)}.
The inverse radiative lifetime of an EHP in a QW \gamma_{r\xi}(\bf{\cal
K}_{\perp})\not=0 only under condition {\cal K}_{\perp}\le\omega_\xi n/c, where
\hbar\omega_\xi is the EHP energy. It has been shown that
\gamma_{r\xi}(\bf{\cal K}_{\perp}) is proportional to H. The values
\gamma_{ra}(\bf{\cal K}_{\perp}) and \gamma_{rb}(\bf{\cal K}_{\perp}) for an
excitation consisting of a hole and a usual magnetopolaron have been
calculated. The index a(b) designates a magnetopolaron upper (lower) term. In
the resonance at H_{res}=m_ec\omega_{LO}/|e|~~
\gamma_{ra}^{res}=\gamma_{rb}^{res}=\gamma_{r\xi_0}^{res}/2, where the index
\xi_0 corresponds to the EHP with n_e=n_h=1. The dependencies {\cal A}(H)$ and
${\cal R}(H) for various values of \omega_l in the magnetophonon resonance
vicinity have been obtained. The existence of "combined"and "weak" polarons has
been predicted. The resonant value H_{res} for the combined polaron case
depends on a QW's depth and width.

</DOC>
<DOC>
<DOCNO> 102499 </DOCNO>
Multiplicity results for some nonlinear Schroedinger equations with


  We prove some multiplicity results for a nonlinear equation of Schroedinger
type with potential functions

</DOC>
<DOC>
<DOCNO> 119030 </DOCNO>
Detection of dark matter concentrations in the field of Cl 1604+4304


  We present a weak-lensing analysis of a region around the galaxy cluster Cl
1604+4304 (z=0.897) on the basis of the deep observations with the {\sl
HST}/WFPC2. We apply a variant of Schneider's aperture mass technique to the
observed WFPC2 field and obtain the distribution of weak-lensing
signal-to-noise (S/N) ratio within the field. The resulting S/N map reveals a
clear pronounced peak located about $1\farcm 7$ ($850h_{50}^{-1}$ kpc at
z=0.897) southwest of the second peak associated with the optical cluster
center determined from the dynamical analysis of Postman et al. A non-linear
finite-field inversion method has been used to reconstruct the projected mass
distribution from the observed shear field. The reconstructed mass map shows a
super-critical feature at the location of the S/N peak as well as in the
cluster central region. Assuming the redshift distribution of field galaxies,
we obtain the total mass in the observed field to be $1.0 h_{50}^{-1}\times
10^{15} M_{\odot}$ for $<z>=1.0$. The estimated mass within a circular aperture
of radius $280h_{50}^{-1}$ kpc centered on the dark clump is
$2.4h_{50}^{-1}\times 10^{14}M_{\odot}$. We have confirmed the existence of the
` dark ' mass concentration from another deep {\sl HST} observation with a
slightly different ($\sim 20\arcsec$) pointing.

</DOC>
<DOC>
<DOCNO> 121993 </DOCNO>
Abundances and Evolution of Lithium in the Galactic Halo and Disk


  We have measured the Li abundance of 18 stars with -2 <~ [Fe/H] ~< -1 and
6000 K <~ Teff <~ 6400 K, a parameter range that was poorly represented in
previous studies. We examine the Galactic chemical evolution (GCE) of this
element, combining these data with previous samples of turnoff stars over the
full range of halo metallicities. We find that A(Li) increases from a level of
\~2.10 at [Fe/H] = -3.5, to ~2.40 at [Fe/H] = -1.0, where A(Li) = log_10
(n(Li)/n(H)) + 12.00.
  We compare the observations with several GCE calculations, including existing
one-zone models, and a new model developed in the framework of inhomogeneous
evolution of the Galactic halo. We show that Li evolved at a constant rate
relative to iron throughout the halo and old-disk epochs, but that during the
formation of young-disk stars, the production of Li relative to iron increased
significantly. These observations can be understood in the context of models in
which post-primordial Li evolution during the halo and old-disk epochs is
dominated by Galactic cosmic ray fusion and spallation reactions, with some
contribution from the $\nu$-process in supernovae. The onset of more efficient
Li production (relative to iron) in the young disk coincides with the
appearance of Li from novae and AGB stars. The major challenge facing the
models is to reconcile the mild evolution of Li during the halo and old-disk
phases with the more efficient production (relative to iron) at [Fe/H] > -0.5.
We speculate that cool-bottom processing (production) of Li in low-mass stars
may provide an important late-appearing source of Li, without attendant Fe
production, that might explain the Li production in the young disk.

</DOC>
<DOC>
<DOCNO> 72016 </DOCNO>
Viable Ultraviolet-Insensitive Supersymmetry Breaking


  It is known that one can add D-term contributions for U(1)_Y and U(1)_{B-L}
to the anomaly-mediated supersymmetry breaking to make the superparticle
spectrum phenomenologically viable. We point out that this can be done without
spoiling its important virtue, namely the ultraviolet insensitivity. This
framework can be derived from supersymmetry breaking and U(1)_{B-L} breaking on
hidden brane(s).

</DOC>
<DOC>
<DOCNO> 10061 </DOCNO>
Chain stiffness intensifies the reptation characteristics of polymer


  The reptation concept in polymer dynamics is studied for model chains with
added stiffness. The main idea of a chain diffusing inside a tube can be
transferred from fully flexible chains. However, the picture, which
renormalizes the chain of locally stiff Kuhn segments onto a flexible chain of
fewer segments fails. The entanglement length shrinks with increasing
persistence length. If entanglement length and persistence length come to the
same order of magnitude the picture of a tight tube is better suited, in which
chain segments can move only along the contour, any transverse motion being
much reduced. Thus, as stiffness increases, the monomers loose their freedom to
perform random walks inside the tube, the ``Rouse-like'' part of their
dynamics. As a result, for persistence lengths of more than five monomers no
length scale can be described by the Rouse model.

</DOC>
<DOC>
<DOCNO> 39922 </DOCNO>
Studies of Neutrino Oscillations at Reactors


  Experiments with reactor neutrinos continue to shed light on our
understanding of neutrino oscillations. We review some of the early decisive
experiments. We then turn to the recent long baseline oscillation experiments
at Palo Verde and Chooz which are leading to the conclusion that the
atmospheric neutrino anomaly if attributed to oscillations does not involve an
appreciable mixing with the $\bar\nu_e$ . The very long baseline KamLAND
experiment is now in the planning stages. Its goal is to help explore the large
mixing angle solar solution. A review of the $\bar\nu_e + d$ experiment at
Bugey and an outline of the $\bar\nu_e$ magnetic moment studies complete this
chapter.

</DOC>
<DOC>
<DOCNO> 10723 </DOCNO>
Hysteresis in an Electrochemical System: Br Electrodeposition on Ag(100)


  We examine hysteresis in cyclic voltammetry of Br electrosorption onto
single-crystal Ag(100) by dynamic Monte Carlo simulations. At room temperature,
this system displays a second-order phase transition from a low-coverage
disordered phase to a doubly degenerate $c (2 \times 2)$ phase. The
electrochemical potential is ramped back and forth across the phase transition,
linearly in time, and the phase lag between the response of the adlayer and the
potential is observed to depend on the sweep rate. The hysteresis in this
system is caused by slow ordering/disordering kinetics and critical
slowing-down.

</DOC>
<DOC>
<DOCNO> 67644 </DOCNO>
Recent Progress in PYTHIA


  PYTHIA is a general-purpose event generator for multiparticle production in
high-energy physics. After a general introduction and program news survey, some
areas of recent physics progress are considered: the matching to matrix
elements, especially for W/Z production; charm and bottom hadronization;
multiple interactions; and interconnection effects. The report concludes with
some words on the future, specifically the ongoing transition to C++.

</DOC>
<DOC>
<DOCNO> 12363 </DOCNO>
Sound emission due to superfluid vortex reconnections


  By performing numerical simulations of superfluid vortex ring collisions we
make direct quantitative measurements of the sound energy released due to
vortex reconnections. We show that the energy radiated expressed in terms of
the loss of vortex line length is a simple function of the reconnection angle.
In addition, we study the temporal and spatial distribution of the radiation
and show that energy is emitted in the form of a rarefaction pulse. The pulse
evolves into a sound wave with a wavelength of 6-8 healing lengths.

</DOC>
<DOC>
<DOCNO> 178691 </DOCNO>
Transverse energy fluctuations and the pattern of J/Psi suppression in


  The NA50 collaboration has recently observed that the J/psi production rate
in Pb-Pb collisions decreases more rapidly as a function of the transverse
energy for the most central collisions than for less central ones. We show that
this phenomenon can be understood as an effect of transverse energy
fluctuations in central collisions. A good fit of the data is obtained using a
model which relates J/psi suppression to the local energy density. Our results
suggest that the J/psi is completely suppressed at the highest densities
achieved in Pb-Pb collisions.

</DOC>
<DOC>
<DOCNO> 71828 </DOCNO>
Resolving the Solar Neutrino Problem with KamLAND


  We study how well KamLAND, the first terrestrial neutrino experiment capable
of addressing the solar neutrino problem, will perform in ascertaining whether
or not the large mixing angle MSW solution (with $10^{-5}<\Delta m_{21}^2<
10^{-4} eV^2$ and oscillation amplitude $sin^2 2 \theta_{12}>0.3$) is correct.
We find that in a year of operation KamLAND will provide unequivocal evidence
for or against this solution. Furthermore, its sensitivity to the
three-neutrino oscillation parameters in this region is sufficiently acute as
to determine $\Delta m_{21}^2$ to approximately $\pm 10$ % (for $sin^2 2
\theta_{12}>0.7$) and to fix $sin^2 2 \theta_{12}$ to within $\pm 0.1$ (at the
$2\sigma$ level) with three years of accumulated data, independent of the value
of $\theta_{13}$.

</DOC>
<DOC>
<DOCNO> 83105 </DOCNO>
Automatic Belief Revision in SNePS


  SNePS is a logic- and network- based knowledge representation, reasoning, and
acting system, based on a monotonic, paraconsistent, first-order term logic,
with compositional intensional semantics. It has an ATMS-style facility for
belief contraction, and an acting component, including a well-defined syntax
and semantics for primitive and composite acts, as well as for ``rules'' that
allow for acting in support of reasoning and reasoning in support of acting.
SNePS has been designed to support natural language competent cognitive agents.
  When the current version of SNePS detects an explicit contradiction, it
interacts with the user, providing information that helps the user decide what
to remove from the knowledge base in order to remove the contradiction. The
forthcoming SNePS 2.6 will also do automatic belief contraction if the
information in the knowledge base warrents it.

</DOC>
<DOC>
<DOCNO> 67832 </DOCNO>
On the structure of systematic perturbation theory with unstable fields


  Discussed is the structure of non-trivial counterterms that occur in the
systematic gauge-invariant perturbation theory with unstable fields introduced
in [hep-ph/9802307].

</DOC>
<DOC>
<DOCNO> 67659 </DOCNO>
The colour dipole approach to small-x processes


  We explain why it is possible to formulate a wide variety of high energy
(small-x) photon-proton processes in terms of a universal dipole cross section
and compare and contrast various parameterizations of this function that exist
in the literature.

</DOC>
<DOC>
<DOCNO> 14106 </DOCNO>
Impurity states and interlayer tunneling in high temperature


  We argue that the Scanning Tunneling Microscope (STM) images of resonant
states generated by doping Zn or Ni impurities into Cu-O planes of BSCCO are
the result of quantum interference of the impurity signal coming from several
distinct paths. The impurity image seen on the surface is greatly affected by
interlayer tunneling matrix elements. We find that the optimal tunneling path
between the STM tip and the metal (Cu, Zn, or Ni) $d_{x^2 - y^2}$ orbitals in
the Cu-O plane involves intermediate excited states. This tunneling path leads
to the four-fold nonlocal filter of the impurity state in Cu-O plane that
explains the experimental impurity spectra. Applications of the tunneling
filter to the Cu vacancy defects and ``direct'' tunneling into Cu-O planes are
also discussed.

</DOC>
<DOC>
<DOCNO> 150860 </DOCNO>
Commuting charges and symmetric spaces


  Every classical sigma-model with target space a compact symmetric space $G/H$
(with $G$ classical) is shown to possess infinitely many local, commuting,
conserved charges which can be written in closed form. The spins of these
charges run over a characteristic set of values, playing the role of exponents
of $G/H$, and repeating modulo an integer $h$ which plays the role of a Coxeter
number.

</DOC>
<DOC>
<DOCNO> 83323 </DOCNO>
Modal Logics for Topological Spaces


  In this thesis we shall present two logical systems, MP and MP, for the
purpose of reasoning about knowledge and effort. These logical systems will be
interpreted in a spatial context and therefore, the abstract concepts of
knowledge and effort will be defined by concrete mathematical concepts.

</DOC>
<DOC>
<DOCNO> 117222 </DOCNO>
Higher-order binding corrections to the Lamb shift of 2P states


  We present an improved calculation of higher-order corrections to the
one-loop self energy of 2P states in hydrogen-like systems with small nuclear
charge Z. The method is based on a division of the integration with respect to
the photon energy into a high- and a low-energy part. The high-energy part is
calculated by an expansion of the electron propagator in powers of the Coulomb
field. The low-energy part is simplified by the application of a
Foldy-Wouthuysen transformation. This transformation leads to a clear
separation of the leading contribution from the relativistic corrections and
removes higher order terms. The method is applied to the 2P_{1/2} and 2P_{3/2}
states in atomic hydrogen. The results lead to new theoretical values for the
Lamb shifts and the fine structure splitting.

</DOC>
<DOC>
<DOCNO> 100227 </DOCNO>
A General Theory of Lee-Yang Zeros in Models with First-Order Phase


  We present a general, rigorous theory of Lee-Yang zeros for models with
first-order phase transitions that admit convergent contour expansions. We
derive formulas for the positions and the density of the zeros. In particular,
we show that for models without symmetry, the curves on which the zeros lie are
generically not circles, and can have topologically nontrivial features, such
as bifurcation. Our results are illustrated in three models in a complex field:
the low-temperature Ising and Blume-Capel models, and the $q$-state Potts model
for $q$ large enough.

</DOC>
<DOC>
<DOCNO> 101066 </DOCNO>
Relative normal modes for nonlinear Hamiltonian systems


  An estimate on the number of distinct relative periodic orbits around a
stable relative equilibrium in a Hamiltonian system with continuous symmetry is
given. This result constitutes a generalization to the Hamiltonian symmetric
framework of a classical result by Weinstein and Moser on the existence of
periodic orbits in the energy levels surrounding a stable equilibrium.The
estimate obtained is very precise in the sense that it provides a lower bound
for the number of relative periodic orbits at each prescribed energy and
momentum values neighboring the stable relative equilibrium in question and
with any prefixed (spatiotemporal) isotropy subgroup. Moreover, it is easily
computable in particular examples. It is interesting to see how in our result
the existence of non trivial relative periodic orbits requires (generic)
conditions on the higher order terms of the Taylor expansion of the Hamiltonian
function, in contrast with the purely quadratic requirements of the
Weinstein--Moser Theorem, which emphasizes the highly non linear character of
the relatively periodic dynamical objects.

</DOC>
<DOC>
<DOCNO> 121671 </DOCNO>
Weak Lensing Determination of the Mass in Galaxy Halos


  We detect the weak gravitational lensing distortion of 450,000 background
galaxies (20<R<23) by 790 foreground galaxies (R<18) selected from the Las
Campanas Redshift Survey (LCRS). This is the first detection of weak lensing by
field galaxies of known redshift, and as such permits us to reconstruct the
shear profile of the typical field galaxy halo in absolute physical units
(modulo H_0), and to investigate the dependence of halo mass upon galaxy
luminosity. This is also the first galaxy-galaxy lensing study for which the
calibration errors are negligible. Within a projected radius of 200 \hkpc, the
shear profile is consistent with an isothermal profile with circular velocity
164+-20 km/s for an L* galaxy, consistent with typical disk rotation at this
luminosity. This halo mass normalization, combined with the halo profile
derived by Fischer et al (2000) from lensing analysis SDSS data, places a lower
limit of (2.7+-0.6) x 10^{12}h^{-1} solar masses on the mass of an L* galaxy
halo, in good agreement with satellite galaxy studies. Given the known
luminosity function of LCRS galaxies, and the assumption that $M\propto
L^\beta$ for galaxies, we determine that the mass within 260\hkpc of normal
galaxies contributes $\Omega=0.16\pm0.03$ to the density of the Universe (for
$\beta=1$) or $\Omega=0.24\pm0.06$ for $\beta=0.5$. These lensing data suggest
that $0.6<\beta<2.4$ (95% CL), only marginally in agreement with the usual
$\beta\approx0.5$ Faber-Jackson or Tully-Fisher scaling. This is the most
complete direct inventory of the matter content of the Universe to date.

</DOC>
<DOC>
<DOCNO> 9114 </DOCNO>
Quantum Tunneling and Quantum-Classical Transitions in Large Spin


  We have studied quantum tunneling of large spins in a biaxial spin system and
in a single-axial spin system with a transverse magnetic field. The
asymptotically exact eigenvalues and eigenstates of the spin systems are
obtained by solving the Mathieu equation. When the height $4q$ of energy
barrier formed by the anisotropy and the magnetic field exceeds some critical
values $4q_{1T}(r)$, the ground states and the excited states split due to
tunneling of large spins. We also have presented the phase diagram of these
spin systems in the extremely weak spin-phonon coupling limit. The crossover
from thermal to quantum regime is second order. With further decreasing
temperature, the first order phase transition occurs from a thermally-assisted
resonant tunneling to thermal regime as $q<q_{1T}(s)$. Our theory agrees with
recent experimental observations well.

</DOC>
<DOC>
<DOCNO> 68065 </DOCNO>
QCD sum rule analysis of excited $\Lambda_c$ mass parameter


  The mass parameter of orbitally excited $\Lambda_c$ baryons is calculated by
using QCD sum rule in the framework of heavy quark effective theory. Two kinds
of interpolating current for the excited heavy baryons are introduced. It is
obtained that $\bar{\Lambda}=1.08^{+0.095}_{-0.104}$ GeV for the non-derivative
current and $\bar{\Lambda}=1.06^{+0.090}_{-0.107}$ GeV for the current with
derivative. These results are consistent with experimental data.

</DOC>
<DOC>
<DOCNO> 117613 </DOCNO>
The Unique Potential of SKA Radio Observations of Gamma-Ray Bursts


  Radio observations with the Square Kilometer Array (SKA) provide the agility,
sensitivity, and spectral coverage to trace the evolution of the size, shape
and spectra of gamma-ray burst (GRB) remnants from the earliest moments on. In
the first hours to days after the burst a major, and unique tool, will be
provided through the study of dynamically evolving radio spectra, caused by
diffractive and refractive scintillation in the local ISM. Simultaneous
observations from optically thin to optically thick frequencies will provide
strong constraints on any model for the GRB remnant. SKA will also allow for
extremely rapid (within minutes, if not seconds) follow-up observations by
electronic steering of the array. SKA observations have the sensitivity to
detect GRB afterglows out to redshifts of 10 or greater. They therefore allow
studies of the high redshift universe, and measure the massive star formation
(and massive star death rate!) history of the universe, unbiased by optical
obscuration. Wide field surveys may detect thousands of GRBs within a few days
of observing (depending on the amount of collimation, the width of the GRB
luminosity function, the number of GRBs like GRB 980425/SN 1998bw). There would
be new ones, but many more would be old, fading afterglows, allowing the
determination of the multi-variate GRB-optical-radio luminosity function of
GRBs. This should elucidate the relation of the `faint' ones, like GRB 980425,
to the luminous ones like GRB 970508. Such surveys will also tell us whether
GRB fireballs (and which ones) are collimated into jets.

</DOC>
<DOC>
<DOCNO> 121359 </DOCNO>
Gravitational Lensing and Cluster of Galaxies


  Multiple images, giant arcs, Einstein cross, fold, cusp, lip, caustics,
critical lines, sources, mapping, time delay, arclets, weak shear,
magnification bias, depletion, ellipticities, polarization, smearing,
convergence, kernel, mass reconstruction, sub-structure, dark halos, natural
telescope, amplification, distant galaxies, faintest sources ... This is a non
exhaustive list of favorite terms used when using gravitational lensing in
clusters of galaxies. I will introduce here lensing in clusters as a useful
tool in modern observational cosmology. I will give a summary of what we are
learning in terms of cluster mass distribution in the strong and weak regime,
and what information we will gain in terms of the cluster physics. I will
underline the benefit of using cluster-lenses as natural telescopes to probe
the distant Universe.

</DOC>
<DOC>
<DOCNO> 40473 </DOCNO>
Observing Spin Correlations in Single Top Production and Decay


  The weak decay of a polarized top quark has a rich structure of angular
correlations among its decay products. We describe some of the noteworthy
features of such decays. We then examine the three modes of single top
production, with an emphasis on the status of calculations of the degree and
direction of polarization at Run II of the Tevatron. The associated production
of a top quark with a W boson will be very difficult to observe at the
Tevatron. Prospects for observing the other two production mechanisms are much
better. The spin state of the produced top quark is understood at leading order
in the W* production channel. For the Wg-fusion process, we present new results
including the resummed logarithmic corrections of the form ln(mt^2/mb^2). The
spin-dependence of the complete order alpha_s corrections to either of these
processes has not yet been determined. The fraction of spin up top quarks is
large (approx. 95%) for both modes provided that the appropriate spin
quantization axis is chosen.

</DOC>
<DOC>
<DOCNO> 70083 </DOCNO>
Semi-inclusive production of pions in DIS and $\bar d - \bar u$


  We discuss the role of some nonpartonic effects which lead to $N_p^{\pi^+}
\ne N_n^{\pi^+}$ and $N_p^{\pi^-} \ne N_n^{\pi^-}$ and may therefore modify the
conclusionon the $\bar d - \bar u$ asymmetry extracted from semi-inclusive
production of pions in DIS. Quantitative estimations for resolved photon and
exclusive $\rho^0$ are given as examples. The results are discussed in the
context of recent HERMES data.

</DOC>
<DOC>
<DOCNO> 152138 </DOCNO>
Tunneling between the giant gravitons in AdS5 x S5


  I consider the giant gravitons in AdS5 x S5. By numerical simulation, I show
a strong indication that there is no instanton solution describing the direct
tunneling between the giant graviton in the S5 and its dual counterpart in the
AdS5. I argue that it supports the supersymmetry breaking scenario suggested in
hep-th/0008015

</DOC>
<DOC>
<DOCNO> 151800 </DOCNO>
Functional Relation of interquark potential with interquark distance


  The functional relation between interquark potential and interquark distance
is explicitly derived by considering the Nambu--Goto action in the $AdS_5
\times S^5$ background. It is also shown that a similar relation holds in a
general background. The implications of this relation for confinement are
briefly discussed.

</DOC>
<DOC>
<DOCNO> 100222 </DOCNO>
Dickson Invariants in the image of the Steenrod Square


  Let D_n be the Dickson invariant ring of F_2[X_1,...,X_n] acted by the
general linear group GL(n,\F_2). In this paper, we provide an elementary proof
of the conjecture by [Hung]: each element in D_n is in the image of the
Steenrod square in F_2[X_1,...,X_n], where n>3.

</DOC>
<DOC>
<DOCNO> 100446 </DOCNO>
Cohomology of the variational complex


  Cohomology of the variational bicomplex in the calculus of variations in
classical field theory are computed in the class of exteriror forms of finite
jet order. This provides a solution of the global inverse problem of the finite
order calculus of variations.

</DOC>
<DOC>
<DOCNO> 11646 </DOCNO>
Aging and response properties in the parking-lot model


  An adsorption-desorption (or parking-lot) model can reproduce qualitatively
the densification kinetics and other features of a weakly vibrated granular
material. Here we study the the two-time correlation and response functions of
the model and demonstrate that their behavior is consistent with recently
observed memory effects in granular materials. Although the densification
kinetics and hysteresis are robust properties, we show that the aging behavior
of the adsorption-desorption model is different from other models of granular
compaction. We propose an experimental test to distinguish the possible aging
behaviors.

</DOC>
<DOC>
<DOCNO> 11514 </DOCNO>
Coherent population transfer in coupled semiconductor quantum dots


  We propose a solid-state implementation of stimulated Raman adiabatic passage
in two coupled semiconductor quantum dots. Proper combination of two pulsed
laser fields allows the coherent carrier transfer between the two
nanostructures without suffering significant losses due to environment
coupling. By use of a general solution scheme for the carrier states in the
double-dot structure, we identify the pertinent dot and laser parameters.

</DOC>
<DOC>
<DOCNO> 102755 </DOCNO>
On Quinn's Invariants of 2-dimensional CW-complexes


  Given a semisimple stable autonomous tensor category over a field $K$, to any
group presentation with finite number of generators we associate an element
$Q(P)\in K$ invariant under the Andrews-Curtis moves. We show that in fact,
this is the same invariant as the one produced by the algorithm of Frank Quinn.
The new definition allows us to present a relatively simple proof of the
invariance and to evaluate $Q(P)$ for some presentations. On the basis of some
numerical calculations over different Gelfand-Kazhdan categories, we make a
conjecture which relates the value of $Q(P)$ for two different classes of
presentations.

</DOC>
<DOC>
<DOCNO> 13956 </DOCNO>
Linear Exp6 Isotherm for Compressed Molten Cesium Over the Whole Liquid


  The linear exp6 isotherm is presented as an approach to the thermodynamic
properies of liquid alkali metals over the whole liquid range including
metal-nonmetal transition. The exp6 pair interaction potential is applied to
approach the underlying interplay between the characteristic soft repulsive
intercation in dense, large attractive interaction in the expanded liquid
alkali metal and the observed thermodynamic properties. PVT of dense liquid
alkali metals obey the linear exp6 isotherm (Z-1)V2=A+Br-7/3
exp{a(1-Cr-1/3/rm)} over the whole range of liquid densities, where Z is the
compression factor, r=1/V is the density, rm is the position of potential
minimum, a is a parameter, and C is constant. The intercept A and the slope B
significantly are related to attraction and repulsion, repectively, and both
depend on temperature. At the level of theory presented in this work, the
thermodynamic effects caused by the polarization of atoms in expanded liquid
alkali metals can be accounted for by exp6 potential function to demonestrat
their thermodynamic properties as normal liquids. This incluids the
metal-nonmetal tarnsition in which case the nature of forces are changed in
such a way that the thermodynamic properties would be different from those of
the high-density region. In particular the equation state for molten cesium is
analytical over the whole range of liquid densities. The linear exp6 isotherm
is used to estimate the binding energy (0.0733 eV) and the position of
potential minimum (0.5336 A) of liquid cesium st freezing temparature.

</DOC>
<DOC>
<DOCNO> 118780 </DOCNO>
HST spectroscopy of the double QSO HS 1216+5032 AB


  (Abridged) We report on HST FOS observations of the double QSO HS 1216+5032
AB (z(A)=1.455; z(B)=1.451, and angular separation theta=9 arcsec). An unusual
broad-absorption-line (BAL) system is observed only in the B component: maximum
outflow velocity of ~5000 km/s; probably a mixture of broad and narrow
components. Observed ions are: HI, CII, CIII, NIII, NV, OVI, and possibly SIV
and SVI. We also discuss two outstanding intervening systems: (1) a complex CIV
system at z=0.72 of similar strength in A and B, with a velocity span of 1500
km/s; and (2) a possible strong MgII system at z=0.04 observed in B only.
  Assuming HS 1216+5032 is a binary QSO, the size of Ly-alpha forest clouds is
constrained using S~ 80 /h_50 kpc at redshifts between z=1.15 and 1.45. Four
Ly-alpha systems not associated with metal lines and producing lines with
W_0>0.17 AA are observed in both spectra, while five appear in only one
spectrum. This sample, although scarce due to the redshift path blocked out by
the BALs in B, allows us to place upper limits on the transverse cloud sizes.
Modelling the absorbers as non-evolving spheres, a maximum-likelihood analysis
yields a most probable cloud diameter D=256 /h_50 kpc and 2 sigma bounds of
172<D<896 /h_50 kpc. If the clouds are modelled as filamentary structures, the
same analysis yields lower transverse dimensions by a factor of two.
Independently of the maximum-likelihood approach, the equivalent width
differences provide evidence for coherent structures. The suggestion that the
size of Ly-alpha forest clouds increases with decreasing redshift is not
confirmed.

</DOC>
<DOC>
<DOCNO> 102723 </DOCNO>
Two-dimensional Artin groups with CAT(0) dimension three


  We exhibit 3-generator Artin groups which have finite 2-dimensional
Eilenberg-Mac Lane spaces, but which do not act properly discontinuously by
semi-simple isometries on a 2-dimensional CAT(0) complex. We prove that
infinitely many of these groups are the fundamental groups of compact,
non-positively curved 3-complexes. These examples show that the geometric
dimension of a CAT(0) group may be strictly less than its CAT(0) dimension.

</DOC>
<DOC>
<DOCNO> 100037 </DOCNO>
On complete arcs arising from plane curves


  We show that the set of F_q-rational points of either certain Fermat curves
or certain F_q-Frobenius non-classical plane curves is a complete (k,d)-arc in
P^2(F_q), where k and d are respectively the number of F_q-rational points and
the degree of the underlying curve.

</DOC>
<DOC>
<DOCNO> 100782 </DOCNO>
Universality of the local spacing distribution in certain ensembles of


  Consider an $N\times N$ hermitian random matrix with independent entries, not
necessarily Gaussian, a so called Wigner matrix. It has been conjectured that
the local spacing distribution, i.e. the distribution of the distance between
nearest neighbour eigenvalues in some part of the spectrum is, in the limit as
$N\to\infty$, the same as that of hermitian random matrices from GUE. We prove
this conjecture for a certain subclass of hermitian Wigner matrices.

</DOC>
<DOC>
<DOCNO> 152269 </DOCNO>
Note on Open String/D-brane System and Noncommutative Soliton


  This is a summary of a series of papers hep-th/9910263,0005283,0010066
written with B. Chen, T. Matsuo and K. Murakami on a p-p', (p<p^{\prime}) open
string with B_{ij} field, which has led us to the explicit identification of
the Dp-brane with the noncommutative projector soliton via the gaussian damping
factor. A lecture given at Summer Institute 2000, FujiYoshida, Yamanashi,
Japan, at August 7-14, 2000.

</DOC>
<DOC>
<DOCNO> 8445 </DOCNO>
Role of Secondary Motifs in Fast Folding Polymers: A Dynamical


  A fascinating and open question challenging biochemistry, physics and even
geometry is the presence of highly regular motifs such as alpha-helices in the
folded state of biopolymers and proteins. Stimulating explanations ranging from
chemical propensity to simple geometrical reasoning have been invoked to
rationalize the existence of such secondary structures. We formulate a
dynamical variational principle for selection in conformation space based on
the requirement that the backbone of the native state of biologically viable
polymers be rapidly accessible from the denatured state. The variational
principle is shown to result in the emergence of helical order in compact
structures.

</DOC>
<DOC>
<DOCNO> 102737 </DOCNO>
The Trajectory-Coherent Approximation and the System of Moments for the


  The general construction of quasi-classically concentrated solutions to the
Hartree-type equation, based on the complex WKB-Maslov method, is presented.
The formal solutions of the Cauchy problem for this equation, asymptotic in
small parameter \h (\h\to0), are constructed with a power accuracy of
O(\h^{N/2}), where N is any natural number. In constructing the
quasi-classically concentrated solutions, a set of Hamilton-Ehrenfest
equations (equations for middle or centered moments) is essentially used. The
nonlinear superposition principle has been formulated for the class of
quasi-classically concentrated solutions of the Hartree-type equations. The
results obtained are exemplified by the one-dimensional equation Hartree-type
with a Gaussian potential.Comments: 6 pages, 4 figures, LaTeX Report no:
Subj-class: Accelerator Physics

</DOC>
<DOC>
<DOCNO> 8803 </DOCNO>
Induced Chern-Simons and WZW action in Noncommutative Spacetime


  We consider noncommutative gauge theory with Dirac or Majorana fermions in
odd dimensional spacetime and compute the induced noncommutative Chern-Simons
action generated at 1-loop. We observe that the Chern-Simons term induced by a
Dirac fermion has a smooth limit when $\th ---> 0$, but there is a finite jump
for the Chern-Simons term induced by a Majorana spinor. The induced
Chern-Simons action from a Majorana spinor is nonvanishing even in the $\th
---> 0$ limit, a discontinuity that shares a similar characteristic as the
UV/IR singularity discovered originally by Minwalla, Raamsdonk and Seiberg.
Properties of the noncommutative WZW action are also discussed.

</DOC>
<DOC>
<DOCNO> 67683 </DOCNO>
Neutrino scattering in strong magnetic fields


  We show that neutrino cross sections are direction dependent in a background
magnetic field.

</DOC>
<DOC>
<DOCNO> 117874 </DOCNO>
Flash-Heating of Circumstellar Clouds by Gamma Ray Bursts


  The blast-wave model for gamma-ray bursts (GRBs) has been called into
question by observations of spectra from GRBs that are harder than can be
produced through optically thin synchrotron emission. If GRBs originate from
the collapse of massive stars, then circumstellar clouds near burst sources
will be illuminated by intense gamma radiation, and the electrons in these
clouds will be rapidly scattered to energies as large as several hundred keV.
Low-energy photons that subsequently pass through the hot plasma will be
scattered to higher energies, hardening the intrisic spectrum. This effect
resolves the "line-of-death" objection to the synchrotron shock model.
Illuminated clouds near GRBs will form relativistic plasmas containing large
numbers of electron-positron pairs that can be detected within ~ 1-2 days of
the explosion before expanding and dissipating. Localized regions of pair
annihilation radiation in the Galaxy would reveal past GRB explosions.

</DOC>
<DOC>
<DOCNO> 118524 </DOCNO>
The Chemical Composition of the Small Magellanic Cloud H II Region NGC


  Spectrophotometry in the 3400-7400 range is presented for 13 areas of the
brightest H II region in the SMC: NGC 346. The observations were obtained at
CTIO with the 4-m telescope. Based on these observations its chemical
composition is derived. The helium and oxygen abundances by mass are given by:
Y(SMC)=0.2405+-0.0018 and O(SMC)=0.00171+-0.00025. From models and observations
of irregular and blue compact galaxies it is found that dY/dO=3.5+-0.9 and
consequently that the primordial helium abundance by mass is given by:
Yp=0.2345+-0.0026 (1-sigma). This result is compared with values derived from
Big Bang nucleosynthesis, and with other determinations of Yp.

</DOC>
<DOC>
<DOCNO> 151576 </DOCNO>
Scherk-Schwarz SUSY Breaking in Noncommutative Field Theory


  Motivated by a recent conjecture [1] that quantum corrections and the UV/IR
connection modify the classical relation between SUSY breaking and the
cosmological constant to the phenomenologically acceptable : $M_{SUSY} \sim M_P
(\Lambda /M_P^4)^{1/8}$, we study SUSY breaking by boundary conditions in
noncommutative field theories. In commutative field theory the violations of
SUSY are finite and vanish as the inverse fourth power of the radius of the
SUSY violating circle. We show that in the noncommutative theory, as a
consequence of its UV/IR connection, the perturbative corrections to SUSY
breaking are infinite. We have not yet performed the nonperturbative
resummations to extract the true behavior of the system.

</DOC>
<DOC>
<DOCNO> 71775 </DOCNO>
Neutralino Proton Cross Sections in SUGRA and D-BRANE Models


  We calculate the spin independent neutralino-proton cross section for
universal SUGRA, non universal SUGRA and D-brane models with R-parity
invariance. The regions of maximum cross section in these models has started to
be probed by the current detectors. The minimum cross section generally is
>~1\times 10^{-(9-10)}pb and hence will be accessible in the future detectors,
barring special regions of parameter space where it can reduce to =~10^{-12}pb.
However, the squarks and gluinos will be heavy (>~1 TeV) in the latter case,
but still accessible at the LHC.

</DOC>
<DOC>
<DOCNO> 102733 </DOCNO>
Temporally stable coherent states for infinite well and P\"oschl-Teller


  This paper is a direct illustration of a construction of coherent states
which has been recently proposed by two of us (JPG and JK). We have chosen the
example of a particle trapped in an infinite square-well and also in
P\"oschl-Teller potentials of the trigonometric type. In the construction of
the corresponding coherent states, we take advantage of the simplicity of the
solutions, which ultimately stems from the fact they share a common SU(1,1)
symmetry \`a la Barut--Girardello. Many properties of these states are then
studied, both from mathematical and from physical points of view.

</DOC>
<DOC>
<DOCNO> 151942 </DOCNO>
Bosonic sector of D=11 superstring action and the critical dimension.


  Bosonic model inspired by D=11 superstring action is investigated. An
appropriate set of variables is find, in which the light-cone quantization
turns out to be possible. It is shown that anomaly terms in the algebra of the
light-cone Poincare generators are absent for the case D=27.

</DOC>
<DOC>
<DOCNO> 7898 </DOCNO>
Non-gaussian electrical fluctuations in a quasi-2d packing of metallic


  The electrical properties of a two-dimensional packing of metallic beads are
studied. Small mechanical perturbations of the packing leads to giant
electrical fluctuations. Fluctuations are found to be non-gaussian and seem to
belong to Levy stable distributions. Anticorrelations have been also found for
the sign of these fluctuations.

</DOC>
<DOC>
<DOCNO> 72051 </DOCNO>
DVCS on the nucleon : study of the twist-3 effects


  We estimate the size of the twist-3 effects on deeply virtual Compton
scattering (DVCS) observables, in the Wandzura-Wilczek approximation. We
present results in the valence region for the DVCS cross sections, charge
asymmetries and single spin asymmetries, to twist-3 accuracy.

</DOC>
<DOC>
<DOCNO> 178788 </DOCNO>
Three-body system in leading order Effective Field Theory without


  The use of leading order effective field theory (EFT) to describe
neutron-deuteron scattering leads to integral equations that have unusual
behaviour: when only two-body interactions are included, the scattering
amplitude does not approach a limit when the cutoff used to solve the equations
is removed. It has recently been shown that this cutoff dependence can be
eliminated by the careful inclusion of a three-body force. In this paper we
show that the cutoff dependence is just a reflection of the fact that the
aforementioned integral equations admit an infinite number of solutions amongst
which only one corresponds to the physical scattering amplitude. We show how to
numerically extract the physical scattering amplitude from the general solution
and in this way explicitly demonstrate that the amplitude for a particle
scattering off a two-body bound state, in leading order EFT, is in fact
determined entirely by two-body forces.

</DOC>
<DOC>
<DOCNO> 118913 </DOCNO>
A modified parallel tree code for N-body simulation of the Large Scale


  N-body codes to perform simulations of the origin and evolution of the Large
Scale Structure of the Universe have improved significantly over the past
decade both in terms of the resolution achieved and of reduction of the CPU
time. However, state-of-the-art N-body codes hardly allow one to deal with
particle numbers larger than a few 10^7, even on the largest parallel systems.
In order to allow simulations with larger resolution, we have first
re-considered the grouping strategy as described in Barnes (1990) (hereafter
B90) and applied it with some modifications to our WDSH-PT (Work and Data
SHaring - Parallel Tree) code. In the first part of this paper we will give a
short description of the code adopting the Barnes and Hut algorithm
\cite{barh86} (hereafter BH), and in particular of the memory and work
distribution strategy applied to describe the {\it data distribution} on a
CC-NUMA machine like the CRAY-T3E system. In the second part of the paper we
describe the modification to the Barnes grouping strategy we have devised to
improve the performance of the WDSH-PT code. We will use the property that
nearby particles have similar interaction list. This idea has been checked in
B90, where an interaction list is builded which applies everywhere within a
cell C_{group} containing a little number of particles N_{crit}. B90 reuses
this interaction list for each particle $ p \in C_{group}$ in the cell in turn.
We will assume each particle p to have the same interaction list.
  Thus it has been possible to reduce the CPU time increasing the performances.
This leads us to run simulations with a large number of particles (N ~
10^7/10^9) in non-prohibitive times.

</DOC>
<DOC>
<DOCNO> 83339 </DOCNO>
On the Average Similarity Degree between Solutions of Random k-SAT and


  To study the structure of solutions for random k-SAT and random CSPs, this
paper introduces the concept of average similarity degree to characterize how
solutions are similar to each other. It is proved that under certain
conditions, as r (i.e. the ratio of constraints to variables) increases, the
limit of average similarity degree when the number of variables approaches
infinity exhibits phase transitions at a threshold point, shifting from a
smaller value to a larger value abruptly. For random k-SAT this phenomenon will
occur when k>4 . It is further shown that this threshold point is also a
singular point with respect to r in the asymptotic estimate of the second
moment of the number of solutions. Finally, we discuss how this work is helpful
to understand the hardness of solving random instances and a possible
application of it to the design of search algorithms.

</DOC>
<DOC>
<DOCNO> 120185 </DOCNO>
Global Cosmological Parameters Determined Using Classical Double Radio


  A sample of 20 powerful extended radio galaxies with redshifts between zero
and two were used to determine constraints on global cosmological parameters.
Data for six radio sources were obtained from the VLA archive, analyzed, and
combined with the sample of 14 radio galaxies used previously by Guerra & Daly
to determine cosmological parameters. The results are consistent with our
previous results, and indicate that the current value of the mean mass density
of the universe is significantly less than the critical value. A universe with
$\Omega_m$ of unity is ruled out at 99.0% confidence, and the best fitting
values of $\Omega_m$ in matter are $0.10^{+0.25}_{-0.10}$ and
$-0.25^{+0.35}_{-0.25}$ assuming zero space curvature and zero cosmological
constant, respectively. Note that identical results obtain when the low
redshift bin, which includes Cygnus A, is excluded; these results are
independent of whether the radio source Cygnus A is included. The method does
not rely on a zero-redshift normalization.
  The radio properties of each source are also used to determine the density of
the gas in the vicinity of the source, and the beam power of the source. The
six new radio sources have physical characteristics similar to those found for
the original 14 sources. The density of the gas around these radio sources is
typical of gas in present day clusters of galaxies. The beam powers are
typically about $10^{45} \hbox{erg s}^{-1}$.

</DOC>
<DOC>
<DOCNO> 121420 </DOCNO>
Neutrino Processes in Supernovae and the Physics of Protoneutron Star


  In preparation for a set of hydrodynamical simulations of core-collapse
supernovae and protoneutron star winds, we investigate the rates of production
and thermalization of $\nu_\mu$ and $\nu_\tau$ neutrinos in dense nuclear
matter. Included are contributions from electron scattering, electron-positron
annihilation, nucleon-nucleon bremsstrahlung, and nucleon scattering. We find
that nucleon scattering dominates electron scattering as a thermalization
process at neutrino energies greater than $\sim$15 MeV. In addition,
nucleon-nucleon bremsstrahlung dominates electron-positron annihilation as a
production mechanism at low neutrino energies, near and below the $\nu_\mu$ and
$\nu_\tau$ neutrinospheres. Furthermore, we have begun a study of steady-state
general relativistic protoneutron star winds employing simple neutrino heating
and cooling terms. From this analysis we obtain acceleration profiles as well
as asymptotic lepton fractions and baryon entropies essential in assessing the
wind as a potential site for $r$-process nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 9436 </DOCNO>
Quasiperiodic time dependent current in driven superlattices: distorted


  Intriguing routes to chaos have been experimentally observed in semiconductor
superlattices driven by an ac field. In this work, a theoretical model of time
dependent transport in ac driven superlattices is numerically solved. In
agreement with experiments, distorted Poincare maps in the quasiperiodic regime
are found. They indicate the appearance of very complex attractors and routes
to chaos as the amplitude of the AC signal increases. Distorted maps are caused
by the discrete well-to-well jump motion of a domain wall during spiky
high-frequency self-sustained oscillations of the current.

</DOC>
<DOC>
<DOCNO> 121186 </DOCNO>
Probing the Structure of Dark Matter in Galaxy Halos and Clusters using


  A new method for measuring gravitational lensing with high redshift type Ia
supernovae is investigated. The method utilizes correlations between foreground
galaxies and supernova brightnesses to substantially reduce possible systematic
errors and increase the signal to noise ratio. It is shown that this lensing
signal can be related to the mass, size and substructure of galaxy halos and
galaxy clusters if dark matter consists of microscopic particles. This
technique may be particularly useful for measuring the size of dark matter
halos, a measurement to which the lensing of galaxies is not well suited, and
for measuring the level of substructure in galaxy halos, a problematic
prediction of the cold dark matter model. The contributions to the signal from
galaxy halos and galaxy clusters are modeled and contributions to the noise
from fluctuations in the galaxy number counts, galaxy redshift error,
dispersion in SN luminosities and sample variance are estimated. The intrinsic
distribution of supernova luminosities and its redshift evolution are removed
as major sources of uncertainty. The method is found to be complimentary to
galaxy--galaxy lensing. The required observations of $\simgt 100$ supernovae
have already been proposed for the purposes of cosmological parameter
estimation.

</DOC>
<DOC>
<DOCNO> 11099 </DOCNO>
Exact Partition Function for the Potts Model with Next-Nearest Neighbor


  We present exact calculations of partition function $Z$ of the $q$-state
Potts model with next-nearest-neighbor spin-spin couplings, both for the
ferromagnetic and antiferromagnetic case, for arbitrary temperature, on
$n$-vertex strip graphs of width $L_y=2$ of the square lattice with free,
cyclic, and M\"obius longitudinal boundary conditions. The free energy is
calculated exactly for the infinite-length limit of these strip graphs and the
thermodynamics is discussed. Considering the full generalization to arbitrary
complex $q$ and temperature, we determine the singular locus ${\cal B}$ in the
corresponding ${\mathbb C}^2$ space, arising as the accumulation set of
partition function zeros as $n \to \infty$.

</DOC>
<DOC>
<DOCNO> 71797 </DOCNO>
Democratic Neutrino Mixing and Radiative Corrections


  The renormalization effect on a specific ansatz of lepton mass matrices,
arising naturally from the breaking of flavor democracy for charged leptons and
that of mass degeneracy for light neutrinos, is studied from a superhigh energy
scale M_0 \sim 10^{13} GeV to the electroweak scale in the framework of the
minimal supersymmetric standard model. We find that the democratic neutrino
mixing pattern obtained from this ansatz may in general be instable against
radiative corrections. With the help of similar flavor symmetries we prescribe
a slightly different scheme of lepton mass matrices at the scale M_0, from
which the democratic mixing pattern of lepton flavors can be achieved, after
radiative corrections, at the experimentally accessible scales.

</DOC>
<DOC>
<DOCNO> 12003 </DOCNO>
Shear-induced particle diffusivities from numerical simulations


  Using Stokesian dynamics simulations, we examine the flow of a monodisperse,
neutrally buoyant, homogeneous suspension of non-Brownian solid spheres in
simple shear, starting from a large number of independent hard-sphere
distributions and ensemble averaging the results. We construct a novel method
for computing the gradient diffusivity via simulations on a {\em homogeneous}
suspension and, although our results are only approximate due to the small
number of particles used in the simulations, we present here the first values
of this important parameter, both along and normal to the plane of shear, which
have ever been obtained directly either experimentally or numerically. We show
furthermore that, although the system of equations describing the particle
motions is deterministic, the particle displacements in the two directions
normal to the bulk flow have Gaussian distributions with zero mean and, a
variance which eventually grows linearly in time thereby establishing that the
system of particles is diffusive. In addition we show that although the
particle evolution equations are, in principle, reversible, the suspension has
in fact a finite correlation time $T_c$ of the order of the inverse shear rate.
For particle concentrations up to 45%, we compute the corresponding tracer
diffusivities both from the slope of the mean square particle displacement as
well as by integrating the corresponding velocity autocorrelations and find
good agreement between the two sets of results.

</DOC>
<DOC>
<DOCNO> 12148 </DOCNO>
Optical absorption from a non degenerate polaron gas


  We apply the Dynamical Mean Field Theory to calculate the low-density limit
of the optical conductivity in the Holstein model. This non perturbative
treatment allows to span continuously from the weak-coupling quasi-free
electron behaviour to the strong-coupling small polaron picture. New features
arise in the intermediate coupling regime: i) a noticeable transfer of spectral
weight towards low frequencies occurs at low temperatures, when coherent
processes acquire importance; ii) thermally activated Polaron Interband
Transitions appear at non zero temperature, whose spectral weight has a non
monotonic temperature behaviour. We propose an interpretation of the infrared
active vibrations (IRAV) observed in the optical spectra of the underdoped
superconducting cuprates in terms of small polarons in the intermediate
coupling regime.

</DOC>
<DOC>
<DOCNO> 10421 </DOCNO>
Supersymmetry solution for finitely extensible dumbbell model


  Exact relaxation times and eigenfunctions for a simple mechanical model of
polymer dynamics are obtained using supersymmetry methods of quantum mechanics.
The model includes the finite extensibility of the molecule and does not make
use of the self-consistently averaging approximation. The finite extensibility
reduces the relaxation times when compared to a linear force. The linear
viscoelastic behaviour is obtained in the form of the ``generalized Maxwell
model''. Using these results, a numerical integration scheme is proposed in the
presence of a given flow kinematics.

</DOC>
<DOC>
<DOCNO> 70271 </DOCNO>
Seesaw model with softly broken L_e - L_\mu - L_\tau


  We enlarge the lepton sector of the Standard Model by adding to it two
right-handed neutrino singlets, and propose a model based on the seesaw
mechanism and on the lepton number $\bar L = L_e - L_\mu - L_\tau$. The model
is innovative from the theoretical point of view in that the $\bar L$-invariant
mass term of the right-handed neutrinos is associated with the large mass scale
responsible for the seesaw mechanism, whereas $\bar L$ is softly broken at a
smaller scale by the remaining Majorana mass terms of the right-handed
neutrinos. While being very economical, the model has predictive power: one
neutrino is massless ($m_3 = 0$), the lepton mixing matrix $U$ features $U_{e3}
= 0$, and the solar-neutrino oscillations have maximal amplitude.

</DOC>
<DOC>
<DOCNO> 68534 </DOCNO>
On mass dependences of the one-loop effective action in simple


  If background fields are soft on the scale set by mass of the particle
involved, a reliable approximation to the field-theoretic one-loop effective
action is obtained by a systematic large mass expansion involving higher-order
Seeley-DeWitt coefficients. Moreover, if the small mass limit of the effective
action in a particular background has been found by some other means, the two
informations may be used to infer the corresponding result for {\em arbitrary}
mass values. This method is used to estimate the one-loop contribution to the
QCD vacuum tunneling amplitude by quarks of arbitrary mass.

</DOC>
<DOC>
<DOCNO> 119295 </DOCNO>
What are MACHOs? Interpreting LMC microlensing


  I discuss two hypotheses that might explain LMC microlensing: the Halo
stellar remnant lensing hypothesis and the unvirialized LMC lensing hypothesis.
I show that white dwarfs cannot contribute substantially to the cosmic baryon
budget; they are strongly constrained by chemical evolution and background
light measurements. Although there have been some claims of direct optical
detections of white dwarfs in the Halo, I show how the full sample of direct
optical searches for halo lenses do not support the Halo lens hypothesis.
  N-body simulations suggest that the LMC may be naturally excited out of
virial equilibrium by tidal forcing from the Milky Way. New measurements of LMC
kinematics not only do not rule out the unvirialized LMC lensing hypothesis,
but even moderately favor it (at 95% confidence).

</DOC>
<DOC>
<DOCNO> 13321 </DOCNO>
Competition and multiscaling in evolving networks


  The rate at which nodes in a network increase their connectivity depends on
their fitness to compete for links. For example, in social networks some
individuals acquire more social links than others, or on the www some webpages
attract considerably more links than others. We find that this competition for
links translates into multiscaling, i.e. a fitness dependent dynamic exponent,
allowing fitter nodes to overcome the more connected but less fit ones.
Uncovering this fitter-gets-richer phenomena can help us understand in
quantitative terms the evolution of many competitive systems in nature and
society.

</DOC>
<DOC>
<DOCNO> 70700 </DOCNO>
\chi_{cJ} polarizations at the Fermilab Tevatron


  We propose the measurement of $\chi_{cJ}$ polarizations at high energy hadron
colliders to study heavy quarkonium production mechanism. We find that the
color-singlet model in the $k_t$ factorization approach predicts very different
behavior for $\chi_{cJ}$ polarizations at the Fermilab Tevatron compared with
the NRQCD predictions in the collinear parton model. In the color-singlet $k_t$
factorization approach, for both $\chi_{c1}$ and $\chi_{c2}$ productions, the
helicity $h=0$ states dominate over other helicity states at large $p_T$. These
properties are very useful in distinguishing between the two production
mechanisms which are related to the interesting issue of $J\psi$ and $\psi'$
polarizations, and may provide a crucial test for the $k_t$ factorization
approach.

</DOC>
<DOC>
<DOCNO> 71301 </DOCNO>
Skewed Parton Distributions and F_2^D at beta -> 1


  We show that the diffractive structure function is perturbatively calculable
in the domain where the diffractive mass is small but still outside the
resonance region. In this domain, which can be characterized by Lambda^2/Q^2 <<
1-beta << (Lambda^2/Q^2)^1/2, the structure function represents a new
observable, which is highly sensitive to the small-x skewed gluon distribution.
Our leading order calculation and the estimate of next-to-leading order
corrections are consistent with available data and demonstrate the potential of
more precise data to put further constraints on skewing effects.

</DOC>
<DOC>
<DOCNO> 10635 </DOCNO>
Supersymmetry in Thermo Field Dynamics


  By considering the enlarged thermal system including the heat bath, it is
shown that this system has supersymmetry which is not broken at finite
temperature. The super algebra is constructed and the Hamiltonian is expressed
as the anti-commutator of two kinds of super charges. With this Hamiltonian and
the thermal vacuum $\mid 0(\beta)>$, this supersymmetry is found to be
preserved.

</DOC>
<DOC>
<DOCNO> 121930 </DOCNO>
A Comparison of UIT Far-Ultraviolet and H alpha Star Formation Rates


  We have used archival ultraviolet (UV) imaging of 50 nearby star-forming
galaxies obtained with the Ultraviolet Imaging Telescope (UIT) to derive
integrated near-UV and far-UV magnitudes, and have combined these data with H
alpha, far-infrared, and thermal radio continuum measurements to explore the
consistency of UV and H alpha star formation rates (SFRs). In agreement with
previous studies, we find that the UV and H alpha SFRs are qualitatively
consistent, even before corrections for extinction are applied. The uncorrected
UV SFRs are systematically lower by a factor of 1.5 (with a factor of two
scatter) among luminous galaxies with SFRs over 1 solar mass per year,
indicating a higher effective attenuation of the far-UV radiation. Among less
luminous galaxies there is no significant offset between the H alpha and far-UV
SFR scales. Far-infrared and thermal radio continuum data available for a
subset of our sample allow us to estimate the attenuation in the UV and at H
alpha independently. The UV and H alpha attenuations appear to be correlated,
and confirm systematically higher attenuations in the UV. Although the galaxies
in our sample show modest levels of attenuation (with median values of 0.9 mag
at H alpha and 1.4 mag at 1550 Angstroms), the range across the sample is
large, around 4 mag for H alpha and around 5 mag in the far-UV (1550
Angstroms). This indicates that the application of a single characteristic
extinction correction to H alpha or UV SFRs is only realistic for large,
well-defined and well-studied galaxy samples, and that extinction bias may be
important for UV or emission-line selected samples of star-forming galaxies.

</DOC>
<DOC>
<DOCNO> 84559 </DOCNO>
The general treatment of high/low energy particle interference phase in


  The interference phase of the high energy mass neutrinos and the low energy
thermal neutrons in a gravitational field are studied. For the mass neutrinos,
we obtain that the phase calculated along the null is equivalent to the half
phase along the geodesic in the high energy limit, which means that the correct
relative phase of the mass neutrinos is either the null phase or the half
geodesic phase.
 Further we point out the importance of the energy condition in calculating the
mass neutrino interference phase. Moreover, we apply the covariant phase to the
calculation of the thermal neutron interference phase, and obtain the
consistent result with that exploited in COW experiment.

</DOC>
<DOC>
<DOCNO> 169678 </DOCNO>
Entanglement and quantum computation with ions in thermal motion


  With bichromatic fields it is possible to deterministically produce entangled
states of trapped ions. In this paper we present a unified analysis of this
process for both weak and strong fields, for slow and fast gates. Simple
expressions for the fidelity of creating maximally entangled states of two or
an arbitrary number of ions under non-ideal conditions are derived and
discussed.

</DOC>
<DOC>
<DOCNO> 170452 </DOCNO>
Optical qubit using linear elements


  A conditional scheme to prepare optical superposition of the vacuum and
one-photon states using linear elements (beam splitters and phase-shifters) and
avalanche photodetectors is suggested.

</DOC>
<DOC>
<DOCNO> 13510 </DOCNO>
Current correlations and quantum localization in 2D disordered systems


  We study long-range correlations of equilibrium current densities in a
two-dimensional mesoscopic system with the time reversal invariance broken by a
random or homogeneous magnetic field. Our result is universal, i.e. it does not
depend on the type (random potential or random magnetic field) or correlation
length of disorder. This contradicts recent sigma-model calculations of
Taras-Semchuk and Efetov (TS&E) for the current correlation function, as well
as for the renormalization of the conductivity. We show explicitly that the new
term in the sigma-model derived by TS&E and claimed to lead to delocalization
does not exist. The error in the derivation of TS&E is traced to an incorrect
ultraviolet regularization procedure violating current conservation and gauge
invariance.

</DOC>
<DOC>
<DOCNO> 122722 </DOCNO>
New Results on the Helium Stars in the Galactic Center Using BEAR


  Integral field spectroscopy of the central parsec of the Galactic Center was
obtained at 2.06 microns using BEAR, an imaging Fourier Transform Spectrometer,
at a spectral resolution of 74 km/s. Sixteen stars were confirmed as helium
stars by detecting the He I 2.058 microns line in emission, providing a
homogeneous set of fully resolved line profiles.
 These observations allow us to discard some of the earlier detections of such
stars in the central cluster and to add three new stars. The sources detected
in the BEAR data were compared with adaptive optics images in the K band to
determine whether the emission was due to single stars. Two sub-classes of
almost equal number are clearly identified from the width of their line
profiles, and from the brightness of their continuum.
 Most of the emission lines show a P Cygni profile. From these results, we
propose that the latter group is formed of stars in or near the LBV phase, and
the other one of stars at the WR stage. The division into two groups is also
shown by their spatial distribution, with the narrow-line stars in a compact
central cluster (IRS 16) and the other group distributed at the periphery of
the central cluster of hot stars. In the same data cube, streamers of
interstellar helium gas are also detected.
 The helium emission traces the densest parts of the SgrA West Mini-Spiral.
Several helium stars have a radial velocity comparable to the velocity of the
interstellar gas in which they are embedded. In the final discussion, all these
findings are examined to present a possible scenario for the formation of very
massive stars in the exceptional conditions of the vicinity of the central
Black Hole.

</DOC>
<DOC>
<DOCNO> 9581 </DOCNO>
Bloch electron in a magnetic field and the Ising model


  The spectral determinant det(H-\epsilon I) of the Azbel-Hofstadter
Hamiltonian H is related to Onsager's partition function of the 2D Ising model
for any value of magnetic flux \Phi=2\pi P/Q through an elementary cell, where
P and Q are coprime integers. The band edges of H correspond to the critical
temperature of the Ising model; the spectral determinant at these (and other
points defined in a certain similar way) is independent of P. A connection of
the mean of Lyapunov exponents to the asymptotic (large Q) bandwidth is
indicated.

</DOC>
<DOC>
<DOCNO> 102446 </DOCNO>
Local characterisation of approximately finite operator algebras


  We show that the family of nest algebras with $r$ non-zero nest projections
is stable, in the sense that an approximate containment of one such algebra
within another is close to an exact containment. We use this result to give a
local characterisation of limits formed from this family. We then consider
quite general regular limit algebras and characterise these algebras using a
local condition which reflects the assumed regularity of the system.

</DOC>
<DOC>
<DOCNO> 102276 </DOCNO>
The Castelnuovo-Mumford regularity of an integral variety of a vector


  The Castelnuovo-Mumford regularity r of a complex, projective variety V is an
upper bound for the degrees of the hypersurfaces necessary to cut out V. In
this note we give a bound for r when V is left invariant by a vector field on
the ambient projective space. More precisely, assume V is arithmetically
Cohen-Macaulay, for instance, a complete intersection. Assume as well that V
projects to a normal-crossings hypersurface, which is the case when V is a
curve with at most ordinary nodes. Then we show that r<m+s+2, where s is the
dimension of V and m is the degree of the vector field. Our method consists of
using first central projections to reduce the problem to when V is a
hypersurface, and then bounds given by Brunella and Mendes.

</DOC>
<DOC>
<DOCNO> 152453 </DOCNO>
The Non-Abelian Self Dual String on the Light Cone


  We construct the scalar profile for the non-abelian self dual string
connecting two M5-branes compactified on a light-like circle. The construction
is based on a conjectured modified version of Nahm's equations describing a
D2-brane, with a magnetic field on it, suspended between two D4-branes. Turning
on a constant magnetic field on the D2-brane corresponds to a boost in the
eleventh direction. In the limit of infinite boost the D4-branes correspond to
light-like compactified M5-branes. The solution for the scalar profile of the
brane remains finite in this limit and displays all the correct expected
features such as smooth interpolation between the unbroken and broken phase
with the correct value for the Higgs field at infinity.

</DOC>
<DOC>
<DOCNO> 122915 </DOCNO>
X-ray emission in the direction of the SNR G318.2+0.1


  We report the discovery of three X-ray sources within the radio shell
G318.2+0.1, one of which may be extended. Two of the sources were detected
during the \sax Galactic Plane Survey and one was found in archival \ros data.
The fainter \sax source is coincident with an ultra-compact galactic H {\sc ii}
region, and we discuss the possibility that it can be a flaring young stellar
object, while the other \sax source has no obvious counterpart. The PSPC source
is consistent with emission from a foreground star. The hard spectrum of the
brighter \sax source is consistent with a non-thermal origin, although a
thermal nature cannot be formally excluded. If this source is associated with
G318.2+0.1, then its hard spectrum suggests that it may be site of non-thermal
electron acceleration.

</DOC>
<DOC>
<DOCNO> 9992 </DOCNO>
Hopping in Disordered Media: A Model Glass Former and A Hopping Model


  Two models involving particles moving by ``hopping'' in disordered media are
investigated:
  I) A model glass-forming liquid is investigated by molecular dynamics under
(pseudo-) equilibrium conditions. ``Standard'' results such as mean square
displacements, intermediate scattering functions, etc. are reported. At low
temperatures hopping is present in the system as indicated by a secondary peak
in the distribution of particle displacements during a time interval 't'. The
dynamics of the model is analyzed in terms of its potential energy landscape
(potential energy as function of the 3N particle coordinates), and we present
direct numerical evidence for a 30 years old picture of the dynamics at
sufficiently low temperatures. Transitions between local potential energy
minima in configuration space are found to involve particles moving in a
cooperative string-like manner.
  II) In the symmetric hopping model particles are moving on a lattice by doing
thermally activated hopping over energy barriers connecting nearest neighbor
sites. This model is analyzed in the extreme disorder limit (i.e. low
temperatures) using the Velocity Auto Correlation (VAC) method. The VAC method
is developed in this thesis and has the advantage over previous methods, that
it can calculate a diffusive regime in finite samples using periodic boundary
conditions. Numerical results using the VAC method are compared to three
analytical approximations, including the Diffusion Cluster Approximation (DCA),
which is found to give excellent agrement with the numerical results.

</DOC>
<DOC>
<DOCNO> 70233 </DOCNO>
Gaussian Sum-Rules and Prediction of Resonance Properties


  Techniques for using Gaussian QCD sum-rules to predict hadronic resonance
properties are developed for single-resonance and two-resonance
phenomenological models, and criteria are developed for determining which of
these models is required for analyzing a particular hadronic channel. The
vector current sum-rule coupled to the $\rho$ meson is shown to be consistent
with a single resonance model, and the Gaussian sum-rule analysis results in an
accurate $\rho$ mass prediction which exhibits excellent agreement between the
theoretical prediction of the Gaussian sum-rule and the phenomenological model.
A two-resonance model is shown to be necessary for the Gaussian sum-rule for
the non-strange quark scalar ($\bar n n$) currents. The two-resonance Gaussian
sum-rule analysis of the isoscalar and isovector ($I=0,1$) $\bar n n$ scalar
mesons exhibits excellent agreement between the theoretical prediction and
phenomenological model. The prediction of the resonance properties of the
$I=0,1$ $\bar n n$ scalar mesons in this two-resonance model provides valuable
information for the interpretation of the scalar mesons, including the X(1775).

</DOC>
<DOC>
<DOCNO> 70129 </DOCNO>
Parton-Based Gribov-Regge Theory


  We present a new parton model approach for hadron-hadron interactions and, in
particular, for the initial stage of nuclear collisions at very high energies
(RHIC, LHC and beyond). The most important aspect of our approach is a
self-consistent treatment, using the same formalism for calculating cross
sections and particle production, based on an effective, QCD-inspired field
theory, where many of the inconsistencies of presently used models will be
avoided.
  In addition, we provide a unified treatment of soft and hard scattering, such
that there is no fundamental cutoff parameter any more defining an artificial
border between soft and hard scattering.
  Our approach cures some of the main deficiencies of two of the standard
procedures currently used: the Gribov-Regge theory and the eikonalized parton
model. There, cross section calculations and particle production cannot be
treated in a consistent way using a common formalism. In particular, energy
conservation is taken care of in case of particle production, but not
concerning cross section calculations. In addition, hard contributions depend
crucially on some cutoff, being divergent for the cutoff being zero. Finally,
in case of several elementary scatterings, they are not treated on the same
level: the first collision is always treated differently than the subsequent
ones. All these problems are solved in our new approach.

</DOC>
<DOC>
<DOCNO> 69623 </DOCNO>
A Study on the Non-perturbative Existence of Yang-Mills Theories with


  Pure lattice SU(2) Yang-Mills theory in five dimensions is considered, where
an extra dimension is compactified on a circle. Monte-Carlo simulations
indicate that the theory possesses a continuum limit with a non-vanishing
string tension if the compactification radius is smaller than a certain value
$R_M$ which is $O(1/10)$ of the inverse of the square root of the string
tension. We verify non-perturbatively the power-law running of gauge coupling
constant. Our method can be applied to the investigation of continuum limits in
other higher-dimensional gauge theories.

</DOC>
<DOC>
<DOCNO> 150559 </DOCNO>
Time Evolution in the External Field: the Unitarity Paradox


  One of the axioms of quantum field theory is the property of unitarity of the
evolution operator. However, if one considers the quantum electrodynamics in
the external field in the leading order of perturbation theory, one will find
that the evolution transformation is a non-unitary canonical transformation of
creation and annihilation operators. This observation was one of the arguments
for the hypothesis that one should choose different representations of the
canonical commutation relations at different moments of time in the exact
quantum field theory. In this paper the contradiction is analyzed for the case
of a simple quantum mechanical model being an analog of the leading order of
the large-N field theory. On the one hand, this model is renormalized with the
help of the constructive field theory methods; the Hilbert space and unitary
evolution operator are constructed. On the other hand, the leading order of the
evolution transformation in the strong external field is shown to be
non-unitary. Thus, unitarity of evolution in the exact theory is not in
contradiction with non-unitarity of the approximate theory.

</DOC>
<DOC>
<DOCNO> 152121 </DOCNO>
Hodge Duality on the Brane


  It has been claimed that whereas scalars can be bound to a Randall-Sundrum
brane, higher p-form potentials cannot, in contradiction with the Hodge duality
between 0-form and 3-form potentials in the five-dimensional bulk. Here we show
that a 3-form in the bulk correctly yields a 2-form on the brane, in complete
agreement with both bulk and brane duality. We also emphasize that the
phenomenon of photon screening in the Randall-Sundrum geometry is ruled out by
the bulk Einstein equation.

</DOC>
<DOC>
<DOCNO> 67819 </DOCNO>
On the Mass and Width of the Z-boson and Other Relativistic Quasistable


  The ambiguity in the definition for the mass and width of relativistic
resonances is discussed, in particular for the case of the Z-boson. This
ambiguity can be removed by requiring that a resonance's width $\Gamma$
(defined by a Breit-Wigner lineshape) and lifetime $\tau$ (defined by the
exponential law) always and exactly fulfill the relation $\Gamma = \hbar/\tau$.
To justify this one needs relativistic Gamow vectors which in turn define the
resonance's mass M_R as the real part of the square root $\rm{Re}\sqrt{s_R}$ of
the S-matrix pole position s_R. For the Z-boson this means that $M_R \approx
M_Z - 26{MeV}$ and $\Gamma_R \approx \Gamma_Z-1.2{MeV}$ where M_Z and
$\Gamma_Z$ are the values reported in the particle data tables.

</DOC>
<DOC>
<DOCNO> 9860 </DOCNO>
Spinor condensates and light scattering from Bose-Einstein condensates


  These notes discuss two aspects of the physics of atomic Bose-Einstein
condensates: optical properties and spinor condensates. The first topic
includes light scattering experiments which probe the excitations of a
condensate in both the free-particle and phonon regime. At higher light
intensity, a new form of superradiance and phase-coherent matter wave
amplification were observed. We also discuss properties of spinor condensates
and describe studies of ground--state spin domain structures and dynamical
studies which revealed metastable excited states and quantum tunneling.

</DOC>
<DOC>
<DOCNO> 151924 </DOCNO>
Extended Objects from Warped Compactifications of M Theory


  We study the massive spectrum of fully wrapped branes in warped M-theory
compactifications, including regimes where these states are parametrically
lighter than the Planck scale or string scale. We show that many such states
behave classically as extended objects in the noncompact directions in the
sense that their mass grows with their size as measured along the Poincare
slices making up the noncompact dimensions. On the other hand these states can
be quantized in a nontrivial regime: in particular their spectrum of
excitations in a limited regime can be obtained by a warped Kaluza-Klein
reduction from ten dimensions. We briefly discuss scattering processes and loop
effects involving these states, and also note the possibility of an exponential
growth in the number of bound states of these objects as a function of energy.

</DOC>
<DOC>
<DOCNO> 68658 </DOCNO>
CP and T violation in neutrino oscillations


  The conditions to induce appreciable CP-and T-odd effects in neutrino
oscillations are discussed. The propagation in matter leads to fake CP-and
CPT-odd asymmetries, besides a Bohm-Aharonov type modification of the
interference pattern. We study the separation of fake and genuine CP violation
by means of energy and distance dependence.

</DOC>
<DOC>
<DOCNO> 71421 </DOCNO>
The heavy neutral Higgs signature in the gamma gamma to Z Z process


  If the Standard Model (SM) Higgs particle is sufficiently heavy, then its
contribution to gamma gamma to Z Z should be largely imaginary, interfering
with the also predominantly imaginary SM "background" generated by the W-loop.
For standard model Higgs masses in the region 200 \lsim m_H \lsim 500 GeV, this
interference is found to be constructive and increasing the Higgs signal. In
the minimal SUSY case an interference effect should also appear for the
contribution of the heavier CP-even neutral Higgs boson H^0, provided it is
sufficiently heavy. The effect is somewhat reduced though, by the smallness of
the H^0 width and the gamma gamma and ZZ branching ratios. The interference is
again found to be constructive for part of the parameter space corresponding to
sfermion masses at the TeV scale and maximal stop mixing. For both the SM and
SUSY cases, regions of the parameter space exist though, where the interference
may be destructive. It is therefore essential to take these effects into
account when searching for possible scalar Higgs-like candidates. To this aim,
we present the complete analytic expressions for both resonance and background
amplitudes.

</DOC>
<DOC>
<DOCNO> 118539 </DOCNO>
Hydrodynamical Models of Accretion Disks in SU UMa Systems


  We numerically test the mode-coupling model (Lubow 1991a) of tidal
instability in SU UMa systems. So far, all numercial models confirming it have
been based on SPH codes and isothermal equation of state. In our paper we
present Eulerian models, using both isothermal approximation and the full
energy equation. We also investigate influence of different ways of mass
transfer. While isothermal models behave similarly to SPH simulations, the
behaviour of models with full energy equation is quite different, and the
mode-coupling model is not confirmed in this case.

</DOC>
<DOC>
<DOCNO> 121009 </DOCNO>
Thermal and Viscous Instability of Accretion Disc in AGN


  The standard accretion discs are known to be thermally and viscously unstable
over a certain range of temperatures. In the inner disc regions there may
develop radiation pressure driven instability, which is possibly related to the
rapid variability detected in AGNs in the UV range. In the outer disc develops
the ionization instability, similar to that in the cataclysmic variables, but
operating on much longer timescales. Due to this process the spectrum of the
accretion disc differs from that of a stationary one.

</DOC>
<DOC>
<DOCNO> 84354 </DOCNO>
Entropy using Path Integrals for Quantum Black Hole Models


  Several eigenvalue equations that could describe quantum black holes have
been proposed in the canonical quantum gravity approach. In this paper, we
choose one of the simplest of these quantum equations to show how the usual
Feynman's path integral method can be applied to obtain the corresponding
statistical properties. We get a logarithmic correction to the
Bekenstein-Hawking entropy as already obtained by other authors by other means.

</DOC>
<DOC>
<DOCNO> 120187 </DOCNO>
Global MHD Simulation of the Inner Accretion Disk in a Pseudo-Newtonian


  We present a detailed three dimensional magnetohydrodynamic (MHD) simulation
describing the inner region of a disk accreting onto a black hole. To avoid the
technical complications of general relativity, the dynamics are treated in
Newtonian fashion using the pseudo-Newtonian Pacz\'ynski-Wiita potential. The
disk evolves due to angular momentum transport which is produced naturally from
MHD turbulence generated by the magnetorotational instability. We find that the
resulting stress is continuous across the marginally stable orbit, in
contradiction with the widely-held assumption that the stress should go to zero
there. As a consequence, the specific angular momentum of the matter accreted
into the hole is smaller than the specific angular momentum at the marginally
stable orbit. The disk exhibits large fluctuations in almost every quantity,
both spatially and temporally. In particular, the ratio of stress to pressure
(the local analog of the Shakura-Sunyaev $\alpha$ parameter) exhibits both
systematic gradients and large fluctuations; from $\sim 10^{-2}$ in the disk
midplane at large radius, it rises to $\sim 10$ both at a few gas density
scaleheights above the plane at large radius, and near the midplane well inside
the plunging region. Driven in part by large-amplitude waves excited near the
marginally stable orbit, both the mass accretion rate and the integrated stress
exhibit large fluctuations whose Fourier power spectra are smooth "red"
power-laws stretching over several orders of magnitude in timescale.

</DOC>
<DOC>
<DOCNO> 9261 </DOCNO>
Properties of the asymptotic nA+mB->C reaction-diffusion fronts


  We discuss, at the mean-field level, the asymptotic shape of the reaction
fronts in the general nA+mB->C reaction-diffusion processes with initially
separated reactants, thus generalizing to arbitrary reaction-order kinetics the
work done by Galfi and Racz for the case n=m=1. Consequences for the formation
of Liesegang patterns are discussed.

</DOC>
<DOC>
<DOCNO> 11665 </DOCNO>
Sequencing of folding events in Go-like proteins


  We have studied folding mechanisms of three small globular proteins: crambin
(CRN), chymotrypsin inhibitor 2 (CI2) and the fyn Src Homology 3 domain (SH3)
which are modelled by a Go-like Hamiltonian with the Lennard-Jones
interactions. It is shown that folding is dominated by a well-defined
sequencing of events as determined by establishment of particular contacts. The
order of events depends primarily on the geometry of the native state.
Variations in temperature, coupling strengths and viscosity affect the
sequencing scenarios to a rather small extent. The sequencing is strongly
correlated with the distance of the contacting aminoacids along the sequence.
Thus $\alpha$-helices get established first. Crambin is found to behave like a
single-route folder, whereas in CI2 and SH3 the folding trajectories are more
diversified. The folding scenarios for CI2 and SH3 are consistent with
experimental studies of their transition states.

</DOC>
<DOC>
<DOCNO> 39988 </DOCNO>
Quasivacuum solar neutrino oscillations


  We discuss in detail solar neutrino oscillations with \delta m^2/E in the
range [10^-10,10^-7] eV^2/MeV. In this range, which interpolates smoothly
between the so-called ``just-so'' and ``Mikheyev-Smirnov-Wolfenstein''
oscillation regimes, neutrino flavor transitions are increasingly affected by
matter effects as \delta m^2/E increases. As a consequence, the usual vacuum
approximation has to be improved through the matter-induced corrections,
leading to a ``quasi-vacuum'' oscillation regime. We perform accurate numerical
calculations of such corrections, using both the true solar density profile and
its exponential approximation. Matter effects are shown to be somewhat
overestimated in the latter case. We also discuss the role of Earth crossing
and of energy smearing. Prescriptions are given to implement the leading
corrections in the quasi-vacuum oscillation range. Finally, the results are
applied to a global analysis of solar nu data in a three-flavor framework.

</DOC>
<DOC>
<DOCNO> 83091 </DOCNO>
SLT-Resolution for the Well-Founded Semantics


  Global SLS-resolution and SLG-resolution are two representative mechanisms
for top-down evaluation of the well-founded semantics of general logic
programs. Global SLS-resolution is linear for query evaluation but suffers from
infinite loops and redundant computations. In contrast, SLG-resolution resolves
infinite loops and redundant computations by means of tabling, but it is not
linear. The principal disadvantage of a non-linear approach is that it cannot
be implemented using a simple, efficient stack-based memory structure nor can
it be easily extended to handle some strictly sequential operators such as cuts
in Prolog.
  In this paper, we present a linear tabling method, called SLT-resolution, for
top-down evaluation of the well-founded semantics. SLT-resolution is a
substantial extension of SLDNF-resolution with tabling. Its main features
include: (1) It resolves infinite loops and redundant computations while
preserving the linearity. (2) It is terminating, and sound and complete w.r.t.
the well-founded semantics for programs with the bounded-term-size property
with non-floundering queries. Its time complexity is comparable with
SLG-resolution and polynomial for function-free logic programs. (3) Because of
its linearity for query evaluation, SLT-resolution bridges the gap between the
well-founded semantics and standard Prolog implementation techniques. It can be
implemented by an extension to any existing Prolog abstract machines such as
WAM or ATOAM.

</DOC>
<DOC>
<DOCNO> 101005 </DOCNO>
Essential self-adjointness for semi-bounded magnetic Schr\"odinger


  We prove essential self-adjointness for semi-bounded below magnetic
Schr\"odinger operators on complete Riemannian manifolds with a given positive
smooth measure which is fixed independently of the metric. Some singularities
of the scalar potential are allowed.
  This is an extension of the Povzner--Wienholtz--Simader theorem. The proof
uses the scheme of Wienholtz but requires a refined invariant integration by
parts technique, as well as a use of a family of cut-off functions which are
constructed by a non-trivial smoothing procedure due to Karcher.

</DOC>
<DOC>
<DOCNO> 170247 </DOCNO>
Entangled webs: Tight bound for symmetric sharing of entanglement


  Quantum entanglement cannot be unlimitedly shared among arbitrary number of
qubits. Larger the number of entangled pairs in an N-qubit system, smaller the
degree of bi-partite entanglement is. We analyze a system of N qubits in which
an arbitrary pair of particles is entangled. We show that the maximum degree of
entanglement (measured in the concurrence) between any pair of qubits is 2/N.
This tight bound can be achieved when the qubits are prepared in a pure
symmetric (with respect to permutations) state with just one qubit in the basis
state |0> and the others in the basis state |1>.

</DOC>
<DOC>
<DOCNO> 84464 </DOCNO>
Couplings of gravity to antisymmetric gauge fields


  We classify all the first-order vertices of gravity consistently coupled to a
system of 2-form gauge fields by computing the local BRST cohomology H(s|d) in
ghost number 0 and form degree n. The consistent deformations are at most
linear in the undifferentiated two-form, confirming the previous results of [1]
that geometrical theories constructed from a nonsymmetric gravity theory are
physically inconsistent or trivial. No assumption is made here on the degree of
homogeneity in the derivatives nor on the form of the gravity action.

</DOC>
<DOC>
<DOCNO> 11389 </DOCNO>
Absence of a metallic phase in random-bond Ising models in two


  When the two-dimensional random-bond Ising model is represented as a
noninteracting fermion problem, it has the same symmetries as an ensemble of
random matrices known as class D. A nonlinear sigma model analysis of the
latter in two dimensions has previously led to the prediction of a metallic
phase, in which the fermion eigenstates at zero energy are extended. In this
paper we argue that such behavior cannot occur in the random-bond Ising model,
by showing that the Ising spin correlations in the metallic phase violate the
bound on such correlations that results from the reality of the Ising
couplings. Some types of disorder in spinless or spin-polarized p-wave
superconductors and paired fractional quantum Hall states allow a mapping onto
an Ising model with real but correlated bonds, and hence a metallic phase is
not possible there either. It is further argued that vortex disorder, which is
generic in the fractional quantum Hall applications, destroys the ordered or
weak-pairing phase, in which nonabelian statistics is obtained in the pure
case.

</DOC>
<DOC>
<DOCNO> 68195 </DOCNO>
Non-Equilibrium Statistical Mechanics of Classical Lattice $\phi^4$


  Classical $\phi^4$ theory in weak and strong thermal gradients is studied on
the lattice in (1+1) dimensions. Classical $\phi^4$ theory in weak and strong
thermal gradients is studied on the lattice in (1+1) dimensions. The steady
state physics of the theory is investigated from first principles and
classified into dynamical regimes. We derive the bulk properties associated
with thermal transport, and explore in detail the non-equilibrium statistical
mechanics of the theory as well as connections to equilibrium and irreversible
thermodynamics. Linear response predictions are found to be valid for systems
quite far from equilibrium and are seen to eventually break down simultaneously
with local equilibrium.

</DOC>
<DOC>
<DOCNO> 10511 </DOCNO>
Density Functional Theory of Magnetic Systems Revisited


  The Hohenberg-Kohn theorem of density functional theory (DFT) for the case of
electrons interacting with an external magnetic field (that couples to spin
only) is examined in more detail than previously. A unexpected generalization
is obtained: in certain cases (which include half metallic ferromagnets and
magnetic insulators) the ground state, and hence the spin density matrix, is
invariant for some non-zero range of a shift in uniform magnetic field. In such
cases the ground state energy is not a functional of the spin density matrix
alone. The energy gap in an insulator or a half metal is shown to be a ground
state property of the N-electron system in magnetic DFT.

</DOC>
<DOC>
<DOCNO> 102182 </DOCNO>
Annular Dehn fillings


  We show that if a simple 3-manifold $M$ has two Dehn fillings at distance
$\Delta \geq 4$, each of which contains an essential annulus, then $M$ is one
of three specific 2-component link exteriors in $S^3$. One of these has such a
pair of annular fillings with $\Delta = 5$, and the other two have pairs with
$\Delta = 4$.

</DOC>
<DOC>
<DOCNO> 178427 </DOCNO>
Collisional Quenching of the 2S State of Muonic Hydrogen


  We have calculated differential, total and transport cross sections for
muonic hydrogen in the n=2 state scattering from hydrogen. The metastable
fraction of the 2S state that slows down below the 2P threshold without
undergoing collisional quenching has been calculated as a function of the
initial kinetic energy using a Monte Carlo kinetics program. Contrary to
earlier estimates, the metastable fraction in the kinetic energy range of 2-5
eV cannot be neglected.

</DOC>
<DOC>
<DOCNO> 69944 </DOCNO>
Spin structure of the octet baryons


  We analyze the semileptonic weak decays of the octet baryons in a "{\em model
independent}" approach, based on the algebraic structure of the Chiral
Quark-Soliton Model. We argue that this analysis is in fact more general than
the model itself. While the symmetry breaking for the semileptonic decays
themselves is not strong, other quantities like $\Delta s$ and $\Delta \Sigma$
are much more affected. We calculate $\Delta \Sigma$ and $\Delta q$ for all
octet baryons. Unfortunately, large experimental errors of $\Xi^-$ decays
propagate in our analysis, in particular, in the case of $\Delta\Sigma $ and
$\Delta s$. Only if the errors for these decays are reduced, the accurate
theoretical predictions for $\Delta\Sigma$ and $\Delta s$ will be possible.

</DOC>
<DOC>
<DOCNO> 169862 </DOCNO>
Local measurements of nonlocal observables and the relativistic


  In this paper we reconsider the constraints which are imposed by relativistic
requirements to any model of dynamical reduction. We review the debate on the
subject and we call attention on the fundamental contributions by Aharonov and
Albert. Having done this we present a new formulation, which is much simpler
and more apt for our analysis, of the proposal put forward by these authors to
perform measurements of nonlocal observables by means of local interactions and
detections. We take into account recently proposed relativistic models of
dynamical reduction and we show that, in spite of some mathematical
difficulties related to the appearence of divergences, they represent a
perfectly appropriate conceptual framework which meets all necessary
requirements for a relativistic account of wave packet reduction. Subtle
questions like the appropriate way to deal with counterfactual reasoning in a
relativistic and nonlocal context are also analyzed in detail.

</DOC>
<DOC>
<DOCNO> 69706 </DOCNO>
Inclusive Heavy Hadron Decays and Light-Cone Dynamics


  The governing role of light-cone dynamics in inclusive heavy hadron decay
processes is demonstrated. Nonperturbative QCD effects on the processes can be
systematically calculated using light-cone expansion and heavy quark effective
theory. The applications of the light-cone approach to studying electroweak and
strong interactions and hadron structure with semileptonic and radiative decays
of beauty hadrons are briefly reviewed.

</DOC>
<DOC>
<DOCNO> 101438 </DOCNO>
How to calculate the Fedosov star--product (Exercices de style)


  This is an expository note on Fedosov's construction of deformation
quantization. Given a symplectic manifold and a connection on it, we show how
to calculate the star-product step by step.
 We draw simple diagrams to solve the recursive equations for the Fedosov
connection and for flat sections of the Weyl algebra bundle corresponding to
functions.
 We also reflect on the differences of symplectic and Riemannian geometries.

</DOC>
<DOC>
<DOCNO> 102578 </DOCNO>
Noncommutative renormalization for massless QED


  We study the renormalization of massless QED from the point of view of the
Hopf algebra discovered by D. Kreimer. For QED, we describe a Hopf algebra of
renormalization which is neither commutative nor cocommutative. We obtain
explicit renormalization formulas for the electron and photon propagators, for
the vacuum polarization and the electron self-energy, which are equivalent to
Zimmermann's forest formula for the sum of all Feynman diagrams at a given
order of interaction.
  Then we extend to QED the Connes-Kreimer map defined by the coupling constant
of the theory (i.e. the homomorphism between some formal diffeomorphisms and
the Hopf algebra of renormalization) by defining a noncommutative Hopf algebra
of diffeomorphisms, and then showing that the renormalization of the electric
charge defines a homomorphism between this Hopf algebra and the Hopf algebra of
renormalization of QED.
  Finally we show that Dyson's formulas for the renormalization of the electron
and photon propagators can be given in a noncommutative (e.g. matrix-valued)
form.

</DOC>
<DOC>
<DOCNO> 100042 </DOCNO>
Hilbertian versus Hilbert W*-modules, and applications to $L^2$- and


  Hilbert(ian) A-modules over finite von Neumann algebras A with a faithful
normal trace state (from global analysis) and Hilbert W*-modules over A (from
operator algebra theory) are compared, and a categorical equivalence is
established. The correspondence between these two structures sheds new light on
basic results in $L^2$-invariant theory providing alternative proofs. We
indicate new invariants for finitely generated projective B-modules, where B is
supposed any unital C*-algebra, (usually the full group C*-algebra $C^*(\pi)$
of the fundamental group $\pi=\pi_1(M)$ of a manifold $M$). The results are of
interest to specialists in operator algebras and global analysis.

</DOC>
<DOC>
<DOCNO> 99555 </DOCNO>
On embeddings into toric prevarieties


  What kind of schemes are embeddable into good toric prevarieties? To shed
some light on this question, we construct proper normal surfaces that are
embeddable into neither simplicial toric prevarieties nor toric prevarieties of
affine intersection.

</DOC>
<DOC>
<DOCNO> 118154 </DOCNO>
The Morphological and Structural Classification of Planetary Nebulae


  We present a statistical analysis of a complete sample (255) of northern
planetary nebulae (PNe).
 Our analysis is based on morphology as a main parameter.
 The major morphological classes are: round (26 % of the sample), elliptical
(61 %), and bipolar (13 %) PNe.
 About a half of the round and 30 % of the elliptical PNe present multiple
shells.
 Round PNe have higher galactic latitude (| b| = 12) and galactic height
 (<z> = 753 pc), than the elliptical (|b| = 7,<z> = 308 pc) and bipolar (|b| =
3, <z>=179 pc). This possibly implies a different progenitor mass range across
morphology, as a different stellar population would suggest.

</DOC>
<DOC>
<DOCNO> 67831 </DOCNO>
Scales of String Theory


  I review the arguments in favor of/against the traditional hypothesis that
the Planck, string and compactification scales are all within a couple of
orders of magnitude from each other. I explain how the extreme brane-world
scenario, with TeV type I scale and two large (near millimetric) transverse
dimensions, creates conditions analogous to those of the energy desert and is
thus naturally singled out. I comment on the puzzle of gauge coupling
unification in this context.

</DOC>
<DOC>
<DOCNO> 102206 </DOCNO>
Decomposition of pure states of a quantum register


  Using the leading vector method, we show that any vector $h\in(C^2)^{\otimes
l}$ can be decomposed as a sum of at most (and at least in the generic case)
$2^l-l$ product vectors using local bitwise unitary transformations. The method
is based on representing the vectors by chains of appropriate simplicial
complex. This generalizes the Scmidt decomposition of pure states of a 2-bit
register to registers of arbitrary length $l$.

</DOC>
<DOC>
<DOCNO> 119310 </DOCNO>
Helioseismic determination of Beryllium neutrinos produced in the Sun


  We provide a determination of the Beryllium neutrino luminosity directly by
means of helioseismology, without using additional assumptions. We have
constructed solar models where Beryllium neutrino, ($\nu_{Be}$) production is
artificially changed by varying in an arbitrary way the zero energy
astrophysical S-factor $S_{34}$ for the reaction $^3{\rm He}+^4{\rm He}\to
^7{\rm Be}+ \gamma$.
  Next we have compared the properties of such models with helioseismic
determinations of photospheric helium abundance, depth of the convective zone
and sound speed profile. We find that helioseismology directly confirms the
production rate of $\nu_{Be}$ as predicted by SSMs to within $\pm 25%$
($1\sigma$ error). This constraint is somehow weaker than that estimated from
uncertainties of the SSM ($\pm 10%$), however it relies on direct observational
data.

</DOC>
<DOC>
<DOCNO> 10663 </DOCNO>
Hopping between Random Locations: Spectrum and Instanton


  Euclidean random matrices appear in a broad class of physical problems
involving disorder. The problem of determining their spectra can be mapped,
using the replica method, into the study of a scalar field theory with an
interaction of the type e^(psi^2). We apply the instanton method to study their
spectral tails.

</DOC>
<DOC>
<DOCNO> 39859 </DOCNO>
Neutrino mass spectrum and neutrinoless double beta decay


  The relations between the effective Majorana mass of the electron neutrino,
$m_{ee}$, responsible for neutrinoless double beta decay, and the neutrino
oscillation parameters are considered. We show that for any specific
oscillation pattern $m_{ee}$ can take any value (from zero to the existing
upper bound) for normal mass hierarchy and it can have a minimum for inverse
hierarchy. This means that oscillation experiments cannot fix in general
$m_{ee}$. Mass ranges for $m_{ee}$ can be predicted in terms of oscillation
parameters with additional assumptions about the level of degeneracy and the
type of hierarchy of the neutrino mass spectrum. These predictions for $m_{ee}$
are systematically studied in the specific schemes of neutrino mass and flavor
which explain the solar and atmospheric neutrino data. The contributions from
individual mass eigenstates in terms of oscillation parameters have been
quantified. We study the dependence of $m_{ee}$ on the non-oscillation
parameters: the overall scale of the neutrino mass and the relative mass
phases. We analyze how forthcoming oscillation experiments will improve the
predictions for $m_{ee}$. On the basis of these studies we evaluate the
discovery potential of future \znbb decay searches. The role \znbb decay
searches will play in the reconstruction of the neutrino mass spectrum is
clarified. The key scales of $m_{ee}$, which will lead to the discrimination
among various schemes are: $m_{ee} \sim 0.1$ eV and $m_{ee} \sim 0.005$ eV.

</DOC>
<DOC>
<DOCNO> 39796 </DOCNO>
On the Structure of the Virtual Compton Amplitude in the Generalized


  A systematic study is performed of the structure of the twist-2 contributions
to the virtual Compton amplitude in deep-inelastic non-forward scattering for
general spin states in the non-local light cone expansion. The gauge invariance
is proven in this approach for the twist-2 contributions for non-forward
scattering. Relations are derived between the contributing non-forward
amplitudes.

</DOC>
<DOC>
<DOCNO> 10382 </DOCNO>
Influence of nonlocal electrodynamics on the anisotropic vortex pinning


  We have studied the pinning force density Fp of YNi_2B_2C superconductors for
various field orientations. We observe anisotropies both between the c-axis and
the basal plane and within the plane, that cannot be explained by usual mass
anisotropy. For magnetic field $H \parallel c$, the reorientation structural
transition in the vortex lattice due to nonlocality, which occurs at a field
$H_1 \sim 1kOe$, manifests itself as a kink in Fp(H). When $H \bot c$, Fp is
much larger and has a quite different H dependence, indicating that other
pinning mechanisms are present. In this case the signature of nonlocal effects
is the presence of a fourfold periodicity of Fp within the basal plane.

</DOC>
<DOC>
<DOCNO> 68129 </DOCNO>
CP violation effect in long-baseline neutrino oscillation in the


  We investigate CP-violation effect in the long-baseline neutrino oscillation
in the four-neutrino model with mass scheme of the two nearly degenerate pairs
separated with the order of 1 eV, by using the data from the solar neutrino
deficit, the atmospheric neutrino anomaly and the LSND experiments along with
the other accelerator and reactor experiments. By use of the most general
parametrization of the mixing matrix with six angles and six phases, we show
that the genuine CP-violation effect could attain as large as 0.3 for $\Delta
P(\nu_\mu\to\nu_\tau) \equiv P(\nu_\mu\to\nu_\tau) -
P(\bar{\nu_\mu}\to\bar{\nu_\tau})$ and that the matter effect is negligibly
small such as at most 0.01 for $\Delta P(\nu_\mu\to\nu_\tau)$ for $\Delta m^2 =
(1-5)\times 10^{-3} {\rm eV}^2$, which is the mass-squared difference relevant
to the long-baseline oscillation.

</DOC>
<DOC>
<DOCNO> 13627 </DOCNO>
Chiral Lagrangians from lattice gauge theories in the strong coupling


  We derive nonlinear sigma models (chiral Lagrangians) over symmetric spaces
U(n), U(2n)/Sp(2n), and U(2n)/O(2n) from U(N), O(N), and Sp(2N) lattice gauge
theories coupled to n flavors of staggered fermions, in the large-N and g^2 N
limit. To this end, we employ Zirnbauer's color-flavor transformation. We prove
the spatial homogeneity of the vacuum configurations of mesons by explicitly
solving the large-N saddle point equations, and thus establish the above
patterns of spontaneous chiral symmetry breaking without any assumptions.

</DOC>
<DOC>
<DOCNO> 100868 </DOCNO>
Quasi-Poisson Manifolds


  A quasi-Poisson manifold is a G-manifold equipped with an invariant bivector
field whose Schouten bracket is the trivector field generated by the invariant
element in $\wedge^3 \g$ associated to an invariant inner product. We introduce
the concept of the fusion for such manifolds, and we relate quasi-Poisson
manifolds to the previously introduced quasi-Hamiltonian manifolds with
group-valued moment maps.

</DOC>
<DOC>
<DOCNO> 119777 </DOCNO>
Stellar Populations in the Nucleus of NGC 6764


  We present first results of near-infrared integral field spectroscopy of the
central 8''$\times$8'' of the Wolf-Rayet nucleus of the barred spiral galaxy
NGC 6764. In addition to stellar CO and Na I absorption lines as well as
recombination lines of H and He I the K-band spectrum shows strong emission
from molecular hydrogen. Analysis of the stellar nuclear light using population
synthesis in conjunction with NIR spectral synthesis suggests either the
presence of two starbursts with ages of $\sim$ 5 Myrs and $\sim$ 20 Myrs or
continuous star formation with an star formation rate of $\sim$ 0.4 \solm
yr^{-1} over the past 1 Gyr.

</DOC>
<DOC>
<DOCNO> 10109 </DOCNO>
Optical conductivity in the normal state fullerene superconductors


  We calculate the optical conductivity, $\sigma(\omega)$, in the normal state
fullerene superconductors by self-consistently including the impurity
scatterings, the electron-phonon and electron-electron Coulomb interactions.
The finite bandwidth of the fullerenes is explicitely considered, and the
vertex corection is included $a$ $la$ Nambu in calculating the renormalized
Green's function. $\sigma(\omega)$ is obtained by calculating the
current-current correlation function with the renormalized Green's function in
the Matsubara frequency and then performing analytic continuation to the real
frequency at finite temperature. The Drude weight in $\sigma(\omega)$ is
strongly suppressed due to the interactions and transfered to the mid-infrared
region around and above 0.06 eV which is somewhat less pronounced and much
broader compared with the expermental observation by DeGiorgi $et$ $al$.

</DOC>
<DOC>
<DOCNO> 121597 </DOCNO>
Differential O and Si Abundances in M33 Early B Supergiants


  We present non-LTE analyses of four M33 early B-supergiant stars and five
Galactic counterparts. This is the first time that B supergiants beyond the
Magellanic Clouds are analyzed by means of detailed Non-LTE techniques. Stellar
temperatures, gravities, microturbulences and Si abundances are derived for all
objects using the Si ionization equilibrium and the Balmer line wings. O
abundances are then also derived. Important approximations made during the
calculations are described, and their influence on the results is analyzed. It
is found that these approximations have no significant effect on the results at
any microturbulence. We find that a strict differential analysis is needed to
detect abundance differences. Thus we compare results line by line in M33 and
Galactic stars of stellar parameters as similar as possible. Three of the four
M33 stars turned out to be O deficient as compared to their Galactic
counterparts, and only one, close to the center of M33 (M33 1054) is found to
be moderately O enriched. From these differential analyses we find that our
data are compatible with a radial O gradient in M33 as that derived from HII
region data: we obtain -0.19+/-0.13 or -0.20+/-0.07 dex/kpc, depending on
whether B133 is included or not. Our data are also consistent with other
possibilities such as a steep increase of the O abundance in the inner region
(at projected distances less than 9 arcmin from the center of M33), followed by
a flat O abundance profile towards the outer parts of M33. Si shows the same
pattern, and it is shown that Si and O correlate well, as expected for
alpha-elements, supporting then the high value of the O abundance gradient in
M33 as compared to the Milky Way and other nearby spiral galaxies.

</DOC>
<DOC>
<DOCNO> 40080 </DOCNO>
High E_T photoproduction and the photon strucure


  Dijet photoproduction results are presented from the H1 and ZEUS
collaborations and compared to next-to-leading order pQCD calculations.

</DOC>
<DOC>
<DOCNO> 12260 </DOCNO>
Strain effect in silicon-on-insulator materials: Investigation with


  We report a detailed experimental and theoretical investigation of the effect
of residual strain, and strain relaxation, which manifests itself at the
Si/SiO$_{2}$ interfaces in commercial silicon-on-insulator (SOI) wafers. SOI
material is made of a single-crystal silicon overlayer (SOL) on top of an
insulator (buried SiO$_{2}$ layer) sitting on a handle silicon wafer. Infrared
reflectivity spectra show that the buried SiO$_{2}$ layer relaxes continuously
when thinning the SOL. At the same time the SOL surface roughness and the
linewidth of optical phonons in Si near the Si/SiO$_2$ interface (probed by
micro-Raman specroscopy) increase. In the as-delivered wafers, this comes from
a slight expansion of Si on both sides of the buried SiO$_{2}$ layer which,
conversely, is compressed. Thinning the SOL modifies these initial equilibrium
conditions. To get quantitative results, we have modeled all our Raman spectra
using a theory of inhomogeneous shift and broadening for optical phonons, which
takes into account the phonon interaction with the static strain fluctuations.
  From the variation of linewidth versus interface distance, we have found that
the mean squared strain continues to relax in the bulk of the wafer through a
depth on the order of several $\mu m$. We also show that the SOL surface
roughness is related to strain fluctuations near the Si/SiO$_2$ interfaces.

</DOC>
<DOC>
<DOCNO> 71379 </DOCNO>
A Constraint on Yukawa-Coupling Unification from Lepton-Flavor Violating


  We present a new constraint on a lepton mixing matrix $V$ from lepton-flavor
violating (LFV) processes in supersymmetric standard models with massive
neutrinos. Here, we assume Yukawa-coupling unification $f_{\nu 3}\simeq f_{\rm
top}$, in which $\tau$-neutrino Yukawa coupling $f_{\nu 3}$ is unified into
top-quark Yukawa coupling $f_{\rm top}$ at the unification scale $M_*\simeq
3\times 10^{16}$ GeV. We show that the present experimental bound on $\mu \to e
\gamma$ decay already gives a stringent limit on the lepton mixing (typically
$V_{13}<0.02$ for $V_{23}=1/\sqrt{2}$). Therefore, many existing neutrino-mass
models are strongly constrained. Future improvement of bounds on LFV processes
will provide a more significant impact on the models with the Yukawa-coupling
unification. We also stress that a precise measurement of a neutrino mixing
$(V_{MNS})_{e3}$ in future neutrino experiments would be very important, since
the observation of non-zero $(V_{MNS})_{e3}$, together with negative
experimental results for the LFV processes, have a robust potential to exclude
a large class of SUSY standard models with the Yukawa-coupling unification.

</DOC>
<DOC>
<DOCNO> 151822 </DOCNO>
Supersymmetric Z_N times Z_M Orientifolds in 4D with D-Branes at Angles


  We construct orientifolds of type IIA string theory. The theory is
compactified on a T^6/Z_N times Z_M orbifold. In addition worldsheet parity in
combination with a reflection of three compact directions is modded out.
Tadpole cancellation requires to add D-6-branes at angles. The resulting four
dimensional theories are N=1 supersymmetric and non-chiral.

</DOC>
<DOC>
<DOCNO> 9022 </DOCNO>
Ground-State Magnetization in Disordered Systems : Exchange vs.


  In a Hartree-Fock picture, itinerant ferromagnetism results from a
competition between kinetic and exchange energy, with the magnetized state
being favored at large interaction strength. In a recent paper \cite{spings} we
showed that in contrast to this average effect, fluctuations of off-diagonal
interaction matrix elements systematically reduce the ground-state
magnetization. When the interaction dominates, the occurence of a non-zero
ground-state magnetization depends on the ratio $\lambda$ between average
exchange energy and the fluctuation amplitude of the off-diagonal matrix
elements, and a nonzero critical value $\lambda_c$ is necessary to magnetize
the ground-state. We extend these results by numerical studies of $\lambda$ for
standard tight-binding models which indicate a regime of intermediate disorder
where off-diagonal fluctuations should play an important role for ground-state
magnetization. We also emphasize the presence of strong correlations between
minimal eigenvalues of different magnetization blocks which further reduce the
probability of a nonzero ground-state spin.

</DOC>
<DOC>
<DOCNO> 71870 </DOCNO>
Neutrino masses through a type II seesaw mechanism at TeV scale


  In this work we show that we can generate neutrino masses through the type-II
see-saw mechanism working at TeV scale in the context of a 331 model.

</DOC>
<DOC>
<DOCNO> 8378 </DOCNO>
Dielectric response of cylindrical nanostructures in a magnetic field


  We study the magnetic field dependence of the dielectric response of large
cylindrical molecules such as nanotubes. When a field-induced level crossing
takes place, an applied electric field causes a linear instead of the usual
quadratic Stark effect. This results in a large dielectric response. Explicit
calculations are performed for doped nanotubes and a rich structure in the real
part of the low-frequency dielectric function $\epsilon'(H)$ is found when a
magnetic field is applied along the cylinder axis. It is suggested that studies
of $\epsilon'(H, T)$ can serve as a spectroscopic tool for the investigation of
large ring-shaped or cylindrical molecules.

</DOC>
<DOC>
<DOCNO> 119078 </DOCNO>
BeppoSAX observations of AM Herculis in intermediate and high states


  Temporal and spectral analyses from BeppoSAX observations of AM Her performed
during both an intermediate and a high state are presented and discussed.
Optical observations taken a few days after the X-ray ones are also presented.
  During the intermediate state observation, the source was in its "normal",
one-pole accretion mode. In the high state it switched to an hitherto
unobserved atypical "two-pole" accretion mode, with significant soft and hard
X-ray emission from both poles. The emission from the second pole is much
softer than that from the primary pole, while the soft X-ray excess of the
primary pole is fairly modest in this accretion mode. These facts suggest that
accretion onto the secondary is mainly due to blobs penetrating deeply in the
photosphere, while that on the primary pole is mostly via a more homogeneous
column, giving rise to the classical standing shock. A strong X-ray flaring
activity is also observed in the soft X-ray band, but not the hard X-ray and
optical emissions indicating that flares are due to inhomogeneous
blobby-accretion events.

</DOC>
<DOC>
<DOCNO> 12032 </DOCNO>
Self-organized critical topology of stock markets


  We have analyzed the cross-correlations of daily fluctuations for N=6 358 US
stock prices during the year 1999. From those $N(N-1)/2$ correlations
coefficients, the Minimum Spanning Tree (MST) has been built. We have
investigated the topology exhibited by the MST. Eventhough the average
topological number is $<n > \approx 2$, the variance $\sigma$ of the
topological distribution f(n) diverges. More precisely, we have found that
$f(n) \sim n^{-2.2}$ holding over two decades. We have studied the topological
correlations for neighbouring nodes: an extremely broad set of local
configurations exists, confirming the divergence of $\sigma$.

</DOC>
<DOC>
<DOCNO> 40325 </DOCNO>
MiniBooNE: Status of the Booster Neutrino Experiment


  MiniBooNE is preparing to search for nu_mu to nu_e oscillations at Fermilab.
The experiment is designed to make a conclusive statement about LSND's neutrino
oscillation evidence. We give a status report on the preparation of the
experiment and outline the experimental prospects.

</DOC>
<DOC>
<DOCNO> 151187 </DOCNO>
A Note on the Path Integral Representation of the Boundary State of


  In this paper we construct path integral representations of the boundary
states in some special backgrounds such as the U(1) gauge field background, the
linear dilaton background and the open string tachyon background. The initial
purpose of this paper is to construct a general solution of the boundary
conformal field theory with the analytical approach, mainly for the constraint
equations$(L_{n}-\tilde{L}_{-n}) |B > =0 $ are difficult to be solved to obtain
the solution represented by string modes from the pure algebraic approach.
However in the path integral representation it is easy transforming those
algebraic equations into the differential equations which can be solved.
Another purpose of this paper is to try to explore an open question. we do not
know how to construct an exact theory of D-branes in the general background
until now. However many recent researches show the boundary state description
indeed seizes some fundamental features of D-branes in the rather special
backgrounds. Since the general background field effects can be easily
introduced in the path integral representation, we argue that path integral
representation of the boundary state should provide an exact description of D
branes in the general backgrounds.

</DOC>
<DOC>
<DOCNO> 12580 </DOCNO>
Can Electric Field Induced Energy Gaps In Metallic Carbon Nanotubes?


  The low-energy electronic structure of metallic single-walled carbon nanotube
(SWNT) in an external electric field perpendicular to the tube axis is
investigated. Based on tight-binding approximation, a field-induced energy gap
is found in all (n, n) SWNTs, and the gap shows strong dependence on the
electric field and the size of the tubes. We numerically find a universal
scaling that the gap is a function of the electric field and the radius of
SWNTs, and the results are testified by the second-order perturbation theory in
weak field limit. Our calculation shows the field required to induce a 0.1
${\rm eV}$ gap in metallic SWNTs can be easily reached under the current
experimental conditions. It indicates a kind of possibility to apply nanotubes
to electric signal-controlled nanoscale switching devices.

</DOC>
<DOC>
<DOCNO> 118905 </DOCNO>
Constraining Galaxy Mass Profiles with Strong Gravitational Lensing


  Measured time delays between the images of a gravitationally lensed source
can lead to a determination of the Hubble constant ($H_o$), but only if the
lensing mass distribution is well understood. The inability to sufficiently
constrain galaxy mass models results in large uncertainties on the derived
$H_o$, and severely hampers the cosmological application of this otherwise
elegant method. At the same time, lensing must compete with new techniques that
have the potential to measure the Hubble constant to within a few percent by
the middle of the decade. In this letter we re-evaluate the role of strong
gravitational lensing in the age of precision cosmology, and present a series
of Monte Carlo simulations that demonstrate the effect of the galaxy mass
distribution on Hubble constant determination. Though most gravitational lens
systems are unlikely to contribute significantly to precision studies of the
cosmological distance scale, the strong dependence of predicted time delays on
the galaxy mass profile suggests that the most useful and interesting results
may be obtained by running the traditional lensing problem in reverse --
namely, combining measured time delays with a well-constrained value of $H_o$
to study galaxy mass distributions.

</DOC>
<DOC>
<DOCNO> 151055 </DOCNO>
A superspace gauge-invariant formulation of a massive tridimensional


  By dimensional reduction of a massive supersymmetric B$\wedge $F theory, a
manifestly N=1 supersymmetric completion of a massive antisymmetric tensor
gauge theory is constructed in (2+1) dimensions. In the N=1-D=3 superspace, a
new topological term is used to give mass for the Kalb-Ramond field. We have
introduced a massive gauge invariant model using the Stuckelberg formalism and
an abelian topologically massive theory for the Kalb-Ramond superfield. An
equivalence of both massive models is suggested. Further, a component field
analysis is performed, showing a second supersymmetry in the model.

</DOC>
<DOC>
<DOCNO> 71975 </DOCNO>
Finite temperature correlation functions


  Lattice measurements of the Pisa group (A.Di Giacomo et al., hep-lat/9603018)
are analyzed numerically and parameters of correlation functions are extracted
from the data - both below and above deconfinement temperature Tc. Gluon
condensate is found for six temperatures in the interval 0.956 Tc - 1.131 Tc
and field distributions in deconfined phase are obtained.

</DOC>
<DOC>
<DOCNO> 120198 </DOCNO>
Infrared Properties of SiO Maser Sources in Late-Type Stars


  Results of an SiO maser survey for the late-type stars selected by the IRTS
(Infrared Telescope in Space) are presented. We have detected SiO J=1-0, v=1
and/or v=2 lines in 27 stars out of 59 stars. The maser intensity increases
with the depth of the H2O absorption in the infrared spectra and redness of the
2.2 and 12 micron color. The column densities of the water vapor in the target
stars are estimated from the depth of the water absorption in the IRTS spectra.
We found that the SiO maser was detected mostly in the stars with the column
density of water vapor higher than 3x10^19-3x10^20 cm^-2. We further estimate
the density of hydrogen molecules in the outer atmosphere corresponding to
these column densities, obtaining 10^9 - 10^10 cm^-3 as a lower limit. These
values are roughly in agreement with the critical hydrogen density predicted by
models for the excitation of the SiO masers. It is possible that the SiO masers
are excited in clumps with even higher than this density. The present results
provide useful information on the understanding of the physical conditions of
the outer atmospheres in late-type stars.

</DOC>
<DOC>
<DOCNO> 123112 </DOCNO>
Extended SZ map of the most luminous X-ray cluster, RXJ1347-1145


  We present in this letter a high resolution (22'' FWHM) extended map at 2.1mm
of the Sunyaev-Zel'dovich effect toward the most luminous X-ray cluster,
RXJ1347-1145. These observations have been performed with the DIABOLO
photometer working at the focus of the 30m IRAM radiotelescope. We have derived
a projected gas mass of $(1.1 \pm 0.1)\times 10^{14} h_{50}^{-5/2}$M$_{\odot}$
within an angular radius of $\theta=74''$ (ie: projected radius of 0.6Mpc,
$H_{0}=50$km/s/Mpc, $\Omega_m=0.3$, $\Omega_\Lambda=0.7$). This result matches
very well the expected gas mass from the cluster models of X-ray data. With an
unprecedented sensitivity level our measurement does not show significant
departure from a spherical distribution. The data analysis also allows us to
characterize the 2.1mm flux of a well known radio source lying in the center of
the cluster: $F_{RS}(2.1\textrm{mm})=5.7\pm 1.6$mJy.

</DOC>
<DOC>
<DOCNO> 68571 </DOCNO>
Neutrino Masses and Mixing at the Millennium


  Recent evidence for neutrino oscillations has revolutionized the study of
neutrino masses and mixing. This report gives an overview of what we are
learning from the neutrino oscillation experiments, the prospects for the near
term, and the bright future of neutrino mass studies.

</DOC>
<DOC>
<DOCNO> 100110 </DOCNO>
Shape Invariant potentials depending on n parameters transformed by


  Shape Invariant potentials in the sense of [Gendenshte\"{\i}n L.\'E., JETP
Lett. 38, (1983) 356] which depend on more than two parameters are not know to
date. In [Cooper F., Ginocchio J.N. and Khare A., Phys. Rev. {\bf 36 D}, (1987)
2458] was posed the problem of finding a class of Shape Invariant potentials
which depend on n parameters transformed by translation, but it was not solved.
We analyze the problem using some properties of the Riccati equation and we
find the general solution.

</DOC>
<DOC>
<DOCNO> 8854 </DOCNO>
Effect of \gamma-irradiation on superconducting transition temperature


  A bulk polycrystalline sample of YBa_(2)Cu_(3)O_(7-\delta) (\delta \approx
0.1) has been irradiated by \gamma-rays with ^{60}Co source. Non-monotonic
behavior of T_{c} with increasing irradiation dose \Phi (up to 220 MR) is
observed: T_{c} decreases at low doses (\Phi < 50 MR) from initial value
(\approx 93 K) by about 2 K and then rises, forming a minimum. At higher doses
(\Phi > 120 MR) T_{c} goes down again. The temperature width of resistive
transition increases rather sharply with dose below 75 MR and drops somewhat at
higher dose. The results observed are discussed, taking into account the
granular structure of sample studied and the influence of \gamma-rays on
intergrain Josephson coupling.

</DOC>
<DOC>
<DOCNO> 120432 </DOCNO>
The Host Stars of Extrasolar Planets Have Normal Lithium Abundances


  The lithium abundances of planet-harbouring stars have been compared with
those of open clusters and field stars. Young (chromospherically active) and
subgiant stars have been eliminated from the comparison because they are at
different stages of evolution and Li processing to the planet-harbouring stars,
and hence have systematically higher Li abundances. The analysis showed that
the Li abundances of the planet-harbouring stars are indistinguishable from
those of non-planet-harbouring stars of the same age, temperature, and
composition. This conclusion is opposite to that arrived at by Gonzalez & Laws
(2000); it is believed that the field star sample used by them contained too
wide a range of ages, evolutionary types, and temperatures to be accommodated
by the model they adopted to describe the dependence on parameters. Li does not
appear set to provide key insights into the formation and evolution of
planetary systems.

</DOC>
<DOC>
<DOCNO> 121918 </DOCNO>
Strong constraints on cosmology from galaxy clusters


  In this work we show how galaxy clusters can be used to discriminate among
different cosmological models. We have used available X-ray & optical cluster
data to constrain the cosmological parameters as well as the cluster scaling
relations, T-M and L-T. We also show the power of future SZE data to constrain
even more these parameters.

</DOC>
<DOC>
<DOCNO> 121580 </DOCNO>
Antikaon condensation and the metastability of protoneutron stars


  We investigate the condensation of $\bar K^0$ meson along with $K^-$
condensation in the neutrino trapped matter with and without hyperons.
Calculations are performed in the relativistic mean field models in which both
the baryon-baryon and (anti)kaon-baryon interactions are mediated by meson
exchange. In the neutrino trapped matter relevant to protoneutron stars, the
critical density of $K^-$ condensation is shifted considerably to higher
density whereas that of $\bar K^0$ condensation is shifted slightly to higher
density with respect to that of the neutrino free case. The onset of $K^-$
condensation always occurs earlier than that of $\bar K^0$ condensation. A
significant region of maximum mass protoneutron stars is found to contain $\bar
K^0$ condensate for larger values of the antikaon potential. With the
appearance of $\bar K^0$ condensation, there is a region of symmetric nuclear
matter in the inner core of a protoneutron star. It is found that the maximum
mass of a protoneutron star containing $K^-$ and $\bar K^0$ condensate is
greater than that of the corresponding neutron star. We revisit the implication
of this scenario in the context of the metastability of protoneutron stars and
their evolution to low mass black holes.

</DOC>
<DOC>
<DOCNO> 99809 </DOCNO>
On Legendrian knots and polynomial invariants


  It is proved in this note that the analogues of the Bennequin inequality
which provide an upper bound for the Bennequin invariant of a Legendrian knot
in the standard contact three dimensional space in terms of the lower degree in
the framing variable of the HOMFLY and the Kauffman polynomials are not sharp.
Furthermore, the relationships between these restrictions on the range of the
Bennequin invariant are investigated, which leads to a new simple proof of the
inequality involving the Kauffman polynomial.

</DOC>
<DOC>
<DOCNO> 70846 </DOCNO>
eps'/eps in the standard model with hadronic matrix elements from the


  I discuss the estimate of the CP-violating parameter eps'/eps based on
hadronic matrix elements computed in the chiral quark model. This estimate
suggested, before the current experimental results, that the favored value of
eps'/eps in the standard model is of the order of 10^{-3}. I briefly review the
physical effects on which this result is based and summarize current estimates.

</DOC>
<DOC>
<DOCNO> 152606 </DOCNO>
Strings as Physical Lines in Vacuum: Basic Concepts for the Computation


  Certain linear objects, termed physical lines, are considered, and initial
assumptions concerning their properties are introduced. A closed physical line
in the form of a circle, termed J-string, is singled out for investigation. It
is shown that this curve consists of indivisible line segments of length
$\ell_\Delta$. It is assumed that a J-string has an angular momentum whose
value is $\hbar$.It is then established that a J-string of radius $R$ possesses
a mass $m_J$, equal to $h/2\pi c R$, a corresponding energy, as well as a
charge $q_J$, where $q_J = (hc/2\pi)^{1/2}$. It is also established that
$\ell_\Delta = 2\pi(hG/c^3)^{1/2}$, where $c$ is the speed of light and $G$ is
the gravitational constant. % Based upon investigation of the properties and
characteristics of J-strings, a method is developed for the computation of the
Planck length and mass $(\ell^*_P, m^*_P)$. The values of $\ell^*_P$ and
$m^*_P$ are computed according to the resulting formulae (and given in the
paper); these values differ from the currently accepted ones.

</DOC>
<DOC>
<DOCNO> 9686 </DOCNO>
Coherent Atomic Oscillations and Resonances between Coupled


  We study the quantum coherent-tunneling between two Bose-Einstein condensates
separated through an oscillating trap potential. The cases of slowly and
rapidly varying in time trap potential are considered. In the case of a slowly
varying trap we study the nonlinear resonances and chaos in the oscillations of
the relative atomic population. Using the Melnikov function approach, we find
the conditions for chaotic macroscopic quantum-tunneling phenomena to exists.
Criteria for the onset of chaos are also given. We find the values of frequency
and modulation amplitude which lead to chaos on oscillations in the relative
population, for any given damping and the nonlinear atomic interaction. In the
case of a rapidly varying trap we use the multiscale expansion method in the
parameter epsilon = 1/Omega, where Omega is the frequency of modulations and we
derive the averaged system of equations for the modes. The analysis of this
system shows that new macroscopic quantum self trapping regions, in comparison
with the constant trap case, exist.

</DOC>
<DOC>
<DOCNO> 83501 </DOCNO>
The Equity Tax and Shelter


  Taxes have major costs beyond the collected revenue: deadweight from
distorted incentives, compliance and enforcement costs, etc. A simple market
mechanism, the Equity Tax, avoids these problems for the trickiest cases:
corporate, dividend, and capital gains taxes.
 It exploits the ability of the share prices to reflect the expected true
annual return (as perceived by investors, not as defined by law) and works only
for publicly held corporations. Since going or staying public cannot be forced,
and for some constitutional reasons too, the conversion to equity tax must be a
voluntary contract. Repeated reconversions would be costly (all capital gains
are realized) and thus rare. The converts and their shareholders pay no income,
dividend, or capital gain taxes. Instead, they give the IRS, say, 2% of stock
per year to auction promptly. Debts are the lender's assets: its status, not
the debtor's, determines their equity-tax or income-tax treatment.
 The system looks too simple to be right. However, it does have no loopholes
(thus lowering the revenue-neutral tax rate), no compliance costs, requires
little regulation, and leaves all business decisions tax neutral. The total
capital the equity taxed sector absorbs is the only thing the tax could
possibly distort. The rates should match so as to minimize this distortion. The
equity tax enlarges the pre-tax profit since this is what the taxpayers
maximize, not a different after-tax net. The wealth shelter is paid for by
efficiency, not by lost tax.

</DOC>
<DOC>
<DOCNO> 151626 </DOCNO>
Noncommutative Scalar Solitons at Finite $\theta$


  We investigate the behavior of the noncommutative scalar soliton solutions at
finite noncommutative scale $\theta$. A detailed analysis of the equation of
the motion indicates that fewer and fewer soliton solutions exist as $\theta$
is decreased and thus the solitonic sector of the theory exhibits an overall
hierarchy structure. If the potential is bounded below, there is a finite
$\theta_c$ below which all the solitons cease to exist even though the
noncommutativity is still present. If the potential is not bounded below, for
any nonzero $\theta$ there is always a soliton solution, which becomes singular
only at $\theta = 0$. The $\phi^4$ potential is studied in detail and it is
found the critical $(\theta m^2)_c =13.92$ ($m^2$ is the coefficient of the
quadratic term in the potential) is universal for all the symmetric $\phi^4$
potential.

</DOC>
<DOC>
<DOCNO> 101575 </DOCNO>
Cyclic homology of the Taft algebras and of their Auslander algebras


  In this paper, we compute the cyclic homology of the Taft algebras and of
their Auslander algebras. Given a Hopf algebra $\Lambda,$ the Grothendieck
groups of projective $\Lambda -$modules and of all $\Lambda -$modules are
endowed with a ring structure, which in the case of the Taft algebras is
commutative (\cite{C2}, \cite{G}). We also describe the first Chern character
for these algebras.

</DOC>
<DOC>
<DOCNO> 99348 </DOCNO>
Calabi-Yau Threefolds and Moduli of Abelian Surfaces I


  We describe birational models and decide the rationality/unirationality of
moduli spaces AA_{d} (and AA^{lev}_{d}) of (1,d)-polarized abelian surfaces
(with canonical level structure, respectively) for small values of d.
  The projective lines identified in the rational/unirational moduli spaces
correspond to pencils of abelian surfaces traced on nodal threefolds living
naturally in the corresponding ambient projective spaces, and whose small
resolutions are new Calabi-Yau threefolds with Euler characteristic zero.

</DOC>
<DOC>
<DOCNO> 40281 </DOCNO>
Ratios of Multijet Cross Sections in p-pbar Collisions at sqrt(s)=1.8


  We report on a study of the ratio of inclusive three-jet to inclusive two-jet
production cross sections as a function of total transverse energy in p-pbar
collisions at a center-of-mass energy sqrt{s} = 1.8 TeV, using data collected
with the D0 detector during the 1992-1993 run of the Fermilab Tevatron
Collider. The measurements are used to deduce preferred renormalization scales
in perturbative O(alpha_s^3) QCD calculations in modeling soft-jet emission.

</DOC>
<DOC>
<DOCNO> 152211 </DOCNO>
Space- and Time-Like Superselection Rules in Conformal Quantum Field


  In conformally invariant quantum field theories one encounters besides the
standard DHR superselection theory based on spacelike (Einstein-causal)
commutation relations and their Haag duality another timelike (''Huygens'')
based superselection structure. Whereas the DHR theory based on spacelike
causality of observables confirmed the Lagrangian internal symmetry picture on
the level of the physical principles of local quantum physics, the attempts to
understand the timelike based superselection charges (associated with the
center of the conformal covering group) in terms of timelike localized charges
lead to a more dynamical role of charges outside the DR theorem and even
outside the Coleman-Mandula setting. The ensuing plektonic timelike structure
of conformal theories explains the spectrum of the anomalous scale dimensions
in terms of phase factors in admissable braid group representations, similar to
the explanation of the possible anomalous spin spectrum expected from
stringlike d=1+2 fields with braid group statistics.

</DOC>
<DOC>
<DOCNO> 99415 </DOCNO>
Domains of holomorphy with edges and lower dimensional boundary


  Necessary and sufficient geometric conditions are given for domains with
regular boundary points and edges to be domains of holomorphy provided the
remainder boundary subset is of zero Hausdorff 1-codimensional measure.

</DOC>
<DOC>
<DOCNO> 117336 </DOCNO>
Relativistic effects in Ni II and the search for variation of the fine


  Theories unifying gravity and other interactions suggest the possibility of
spatial and temporal variation of physical ``constants'' in the Universe.
Detection of high redshift absorption systems intersecting the sight lines
towards distant quasars provide a powerful tool for measuring these variations.
In the present paper we demonstrate that high sensitivity to variation of the
fine structure constant alpha can be obtained by comparing cosmic and
laboratory spectra of the Ni II ion. Relativistic effects in Ni II reveal many
interesting features. The Ni II spectrum exhibits avoided level crossing
phenomenon under variation of alpha and the intervals between the levels have
strong nonlinear dependencies on relativistic corrections. The values of the
transition frequency shifts, due to the change of alpha, vary significantly
from state to state including change of the sign. This enhances the sensitivity
to the variation of alpha and reduces possible systematic errors. The
calculations of alpha-dependence of the nickel ion spectral lines that are
detectable in quasar absorption spectra have been performed using a
relativistic configuration interaction method.

</DOC>
<DOC>
<DOCNO> 122567 </DOCNO>
An Ultraviolet Study of the Short-Period Binary OO Aquilae


  OO Aql is a rare W UMa-type eclipsing binary in which the two solar-type
stars may have only recently evolved into contact. The binary has an unusually
high mass ratio (0.84), and a relatively long orbital period (0.506 d) for it
spectral type (mid-G). Twelve ultraviolet spectra of OO Aql were obtained in
1988 with the IUE satellite, including a series of consecutive observations
that cover nearly a complete orbital cycle. Chromospheric activity is studied
by means of the Mg II h+k emission at 2800 A. The Mg II emission is found to
vary, even when the emission is normalized to the adjacent continuum flux. This
variation may be correlated with orbital phase in the 1988 observations. It
also appears that the normalized Mg II emission varies with time, as seen in
spectra obtained at two different epochs in 1988 and when compared with two
spectra obtained several years earlier. The level of chromospheric activity in
OO Aql is less than that of other W UMa-type binaries of similar colors, but
this is attributed to its early stage of contact binary evolution. Ultraviolet
light curves were composed from measurements of the ultraviolet continuum in
the spectra. These were analyzed along with visible light curves of OO Aql to
determine the system parameters. The large wavelength range in the light curves
enabled a well-constrained fit to a cool spot in the system.

</DOC>
<DOC>
<DOCNO> 85618 </DOCNO>
Spin, gravity, and inertia


  The gravitational effects in the relativistic quantum mechanics are
investigated. The exact Foldy-Wouthuysen transformation is constructed for the
Dirac particle coupled to the static spacetime metric. As a direct application,
we analyze the non-relativistic limit of the theory. The new term describing
the specific spin (gravitational moment) interaction effect is recovered in the
Hamiltonian. The comparison of the true gravitational coupling with the purely
inertial case demonstrates that the spin relativistic effects do not violate
the equivalence principle for the Dirac fermions.

</DOC>
<DOC>
<DOCNO> 122275 </DOCNO>
The Local Stellar Initial Mass Function


  This contribution describes the difficult task of inferring the IMF from
local star-count data, by discussing the mass-luminosity relation, unresolved
binary, triple and quadruple systems, abundance and age spreads and Galactic
structure, all of which must be accounted for properly for the results to be
meaningful. A consensus emerges that the local IMF may be represented by a
two-part power-law, with indices alpha=1-1.5 for stars with mass m<0.5 Msun,
and the Salpeter value alpha=2.3 for more massive stars, but some uncertainties
remain. Notable is also that the sensitivity of the stellar luminosity function
(LF) to the derivative of the mass-luminosity relation is very evident in the
(local) Hipparcos and HST, open-cluster and globular-cluster LFs, thus allowing
tests of stellar structure theory. The upcoming astrometry space missions DIVA
and GAIA will undoubtedly lead to significant advances in this field.

</DOC>
<DOC>
<DOCNO> 151517 </DOCNO>
Dimensional regularization of the path integral in curved space on an


  We use dimensional regularization to evaluate quantum mechanical path
integrals in arbitrary curved spaces on an infinite time interval. We perform
3-loop calculations in Riemann normal coordinates, and 2-loop calculations in
general coordinates. It is shown that one only needs a covariant two-loop
counterterm (V_{DR} = R/8) to obtain the same results as obtained earlier in
other regularization schemes. It is also shown that the mass term needed in
order to avoid infrared divergences explicitly breaks general covariance in the
final result.

</DOC>
<DOC>
<DOCNO> 12141 </DOCNO>
Resonant tunneling through zero-dimensional impurity states: Effects of


  We have performed temperature dependent tunneling experiments through a
single impurity in an asymmetric vertical double barrier tunneling structure.
In particular in the charging direction we observe at zero magnetic field a
clear shift in the onset voltage of the resonant tunneling current through the
impurity. With a magnetic field applied the shift starts to disappear. The
experimental observations are explained in terms of resonant tunneling through
a spin degenerate impurity level.

</DOC>
<DOC>
<DOCNO> 80632 </DOCNO>
Nonperturbative Dynamics of Noncommutative Gauge Theory


  We present a nonperturbative lattice formulation of noncommutative Yang-Mills
theories in arbitrary even dimension. We show that lattice regularization of a
noncommutative field theory requires finite lattice volume which automatically
provides both an ultraviolet and an infrared cutoff. We demonstrate explicitly
Morita equivalence of commutative U(p) gauge theory with (p*n_f) flavours of
fundamental matter fields on a lattice of size L with twisted boundary
conditions and noncommutative U(1) gauge theory with n_f species of matter on a
lattice of size (p*L) with single-valued fields. We discuss the relation with
twisted large N reduced models and construct observables in noncommutative
gauge theory with matter.

</DOC>
<DOC>
<DOCNO> 70425 </DOCNO>
Quark combinatorics and meson production ratios in hadronic Z^0 decays


  Rich experimental data accumulated in the past few years in the hadronic
$Z^0$ decays allow one to check the quark combinatorics relations for a new
type of processes, namely: quark jets in the decays $Z^0 \to q\bar q \to
hadrons$. In this paper we review quark combinatorics rules for the yields of
vector and pseudoscalar mesons, $V/P$, in the central and fragmentation regions
of the hadronic $Z^0$ decays. It is stressed that in the central region a
direct verification of quark combinatorics rules is rather problematic because
of a considerable background related to the decay of highly excited resonances;
however such a verification is possible in the fragmentation region, at
$x_{hadron} \sim 0.5-1$, where the contribution of resonance decays is
suppressed due to the rapid decrease of spectra with increasing $x_{hadron}$.
It is shown that the experimental data in the fragmentation region for
$\rho^0/\pi^0$ and $p/\pi^+$ are in a reasonable agreement with the predictions
of quark combinatorics. The ratios of the heavy meson yields, $B^*/B$ and
 $D^*/D$, are also discussed: the data demonstrate a good agreement with the
quark combinatorial results. We analyse the structure of the suppression
parameters for strange and heavy quark productions in soft processes and
estimate their order of magnitudes in the multiperipheral processes; the ratio
$K^{\pm}/\pi^{\pm}$ at $x_{hadron}\sim 0.5-0.8$ and production probabilities of
the $c\bar c$ and $b \bar b$ mesons are in a good agreement with the estimates.

</DOC>
<DOC>
<DOCNO> 68271 </DOCNO>
Effects of a dynamical role for exchanged quarks and nuclear gluons in


  It is shown that new data from the HERMES collaboration, as well as all of
the earlier improved data from experiments concerning the EMC effect and
shadowing in deep-inelastic scattering of leptons from nuclei, provide strong
evidence for an explicit dynamical role played by exchanged quarks and nuclear
gluons in the basic, tightly-bound systems of three and four nucleons, He3 and
He4. This opens the way for specific quark-gluon dynamics instigating
multinucleon correlations in nuclei.

</DOC>
<DOC>
<DOCNO> 101734 </DOCNO>
Classification, Casimir Invariants, and Stability of Lie-Poisson Systems


  We classify Lie-Poisson brackets that are formed from Lie algebra extensions.
The problem is relevant because many physical systems owe their Hamiltonian
structure to such brackets. A classification involves reducing all brackets to
a set of normal forms, independent under coordinate transformations, and is
achieved with the techniques of Lie algebra cohomology. For extensions of order
less than five, we find that the number of normal forms is small and they
involve no free parameters. A special extension, known as the Leibniz
extension, is shown to be the unique ``maximal'' extension.
  We derive a general method of finding Casimir invariants of Lie-Poisson
bracket extensions. The Casimir invariants of all brackets of order less than
five are explicitly computed, using the concept of `coextension.' We obtain the
Casimir invariants of Leibniz extensions of arbitrary order. We also offer some
physical insight into the nature of the Casimir invariants of compressible
reduced magnetohydrodynamics.
  We make use of the methods developed to study the stability of extensions for
given classes of Hamiltonians. This helps to elucidate the distinction between
semidirect extensions and those involving cocycles. For compressible reduced
magnetohydrodynamics, we find the cocycle has a destabilizing effect on the
steady-state solutions.

</DOC>
<DOC>
<DOCNO> 70717 </DOCNO>
Radiatively corrected shape function for inclusive heavy hadron decays


  We discuss the non-perturbative and the radiative corrections to inclusive B
decays from the point of view known from QED corrections to high energy e^+ e^-
processes. Here the leading contributions can be implemented through the so
called ``radiator function'' which corresponds to the shape function known in
heavy hadron decays. In this way some new insight into the origin of the shape
function is obtained. As a byproduct, a parameterization of the radiatively
corrected shape function is suggested which can be implemented in Monte Carlo
studies of inclusive heavy hadron decays.

</DOC>
<DOC>
<DOCNO> 84390 </DOCNO>
Comparative Studies of Lensing Methods


  Predictions of the standard thin lens approximation and a new iterative
approach to gravitational lensing are compared with an ``exact'' approach in
simple test cases involving one or two lenses. We show that the thin lens and
iterative approaches are remarkably accurate in predicting time delays, source
positions and image magnifications for a single monopole lens and combinations
of two monopole lenses. In the cases studied, the iterative method provided
greater accuracy than the thin lens method. We also study the accuracy of a ``2
lens, single lens plane model,'' where two monopole lenses colinear with the
observer are modeled by a mass distribution in a single lens plane lying
between them. We see that this model can lead to large inaccuracies in
physically meaningful situations.
  A previous version of this paper was published as Phys.Rev.D62, 024025,
(2000) with errors in the computation of two lens comparisons. This paper
corrects these errors and presents new conclusions which differ from the
previous version.

</DOC>
<DOC>
<DOCNO> 13984 </DOCNO>
The Temperature Evolution of the Spectral Peak in High Temperature


  Recent photoemission data in the high temperature cuprate superconductor
Bi2212 have been interpreted in terms of a sharp spectral peak with a
temperature independent lifetime, whose weight strongly decreases upon heating.
By a detailed analysis of the data, we are able to extract the temperature
dependence of the electron self-energy, and demonstrate that this intepretation
is misleading. Rather, the spectral peak loses its integrity above Tc due to a
large reduction in the electron lifetime.

</DOC>
<DOC>
<DOCNO> 101938 </DOCNO>
Riemannian Geometries


  This paper discusses a non-commutative version of the fundamental class of a
smooth closed Riemannian manifold, no spin structure assumed. The formulation
uses Connes' non-comm. geometry, Kasparov's KK-theory and the standard theory
of von Neumann algebras. Using an axiom scheme based on the spin case,
Riemannian manifolds are recovered when the algebra in question is commutative.

</DOC>
<DOC>
<DOCNO> 152578 </DOCNO>
Gauge-fixing independence of IR divergences in non-commutative U(1),


  It is argued that the quadratic and linear non-commutative IR divergences
that occur in U(1) theory on non-commutative Minkowski spacetime for small
non-commutativity matrices $\theta^{\mu\nu}$ are gauge-fixing independent. This
implies in particular that the perturbative tachyonic instability produced by
the quadratic divergences of this type in the vacuum polarization tensor is not
a gauge-fixing artifact. Supersymmetry can be introduced to remove from the
renormalized Green functions at one loop, not only the non-logarithmic
non-commutative IR divergences, but also all terms proportional to
$\theta^{\mu\nu}p_\nu$

</DOC>
<DOC>
<DOCNO> 9484 </DOCNO>
Phenomenological model of high-Tc superconductivity


  We present a phenomenological model of high-Tc superconductivity in
hole-doped cuprates: a Magnetic Coupling between Stripes (MCS) model. The MCS
model is based upon experimental facts, namely, the presence of (i) stripes,
(ii) spin fluctuations, and (iii) two order parameters (for pairing and
long-range phase coherence) in hole-doped cuprates. We discuss also the
superconductivity in electron-doped cuprates.

</DOC>
<DOC>
<DOCNO> 120199 </DOCNO>
Turbulent Molecular Cloud Cores: Rotational Properties


  The rotational properties of centrally condensed, turbulent molecular cloud
cores with velocity fields that are characterized by Gaussian random fields are
investigated. It is shown that the observed line width-size relationship can be
reproduced if the velocity power spectrum is a power-law with P(k)=k**n and
n=-3 to -4. The line-of-sight velocity maps of these cores show velocity
gradients that can be interpreted as rotation. For n=-4, both, the deduced
values of the angular velocity Omega=1.6 km/s/pc * (R/0.1 pc)**0.5 and the
scaling relations between Omega and the core radius R are in very good
agreement with the observations. As a result of the dominance of long
wavelength modes, the cores also have a net specific angular momentum with an
average value of j=7*(10**20)*(R/0.1 pc)**(1.5) cm**2/s with a large spread.
Their internal dimensionless rotational parameter is beta=0.03, independent of
the scale radius R. In general, the line-of-sight velocity gradient of an
individual turbulent core does not provide a good estimate of its internal
specific angular momentum. We find however that the distribution of the
specific angular momenta of a large sample of cores which are described by the
same power spectrum can be determined very accurately from the distribution of
their line-of-sight velocity gradients Omega using the simple formula
j=p*Omega*R*R where p depends on the density distribution of the core and has
to be determined from a Monte-Carlo study. Our results show that for centrally
condensed cores the intrinsic angular momentum is overestimated by a factor of
2-3 if p=0.4 is used.

</DOC>
<DOC>
<DOCNO> 68117 </DOCNO>
Finite pion width effects on the rho-meson and di-lepton spectra


  Within a field theoretical model where all damping width effects are treated
self-consistently we study the changes of the spectral properties of rho-mesons
due to the finite damping width of the pions in dense hadronic matter at finite
temperature. The corresponding effects in the di-lepton yields are presented.
Some problems concerning the self consistent treatment of vector or gauge
bosons are discussed.

</DOC>
<DOC>
<DOCNO> 116427 </DOCNO>
Hierarchic theory of condensed matter and its interaction with light:


  1: New approach to theory of light refraction 1.1. Refraction in gas; 1.2.
Light refraction in liquids and solids 2: Mesoscopic theory of Brillouin light
scattering 2.1. Traditional approach; 2.2. Fine structure of scattering; 2.3.
Mesoscopic approach; 2.4. Quantitative verification of hierarchic theory of
Brillouin scattering 3: Mesoscopic theory of Mossbauer effect 3.1. General
background; 3.2. Probability of elastic effects; 3.3. Doppler broadening in
spectra nuclear gamma-resonance (NGR) 3.4. Acceleration and forces, related to
thermal dynamics of molecules and ions.
  Vibro-gravitational interaction

</DOC>
<DOC>
<DOCNO> 123125 </DOCNO>
Towards a Precise Measurement of Matter Clustering: Lyman-alpha Forest


  We measure the filling factor, correlation function, and power spectrum of
transmitted flux in a large sample of Lya forest spectra, comprised of 30 Keck
HIRES and 23 Keck LRIS spectra. We infer the linear matter power spectrum P(k)
from the flux power spectrum P_F(k), using an improved version of the method of
Croft et al. (1998) that accounts for the influence of redshift-space
distortions, non-linearity, and thermal broadening on the shape of P_F(k). The
evolution of P(k) over the redshift of the sample (z ~ 2-4) is consistent with
gravitational instability, implying that non-gravitational fluctuations do not
make a large contribution. Our fiducial measurement of P(k) is from data with
2.3<z<2.9 (<z> = 2.72). The P(k) has amplitude Delta^2(k_p)= 0.54^+0.14_-0.12
at k_p=0.03(kms^-1)^-1; it is well described by a power-law of index nu = -2.47
+/-0.06 or by a CDM-like form with shape Gamma'= 9.6^+4.3_-4.8*10^-4
(kms^-1)^-1 at z=2.72 (1 sig errors). This is close to the predictions of
leading cosmological models, but different enough to create slight tensions on
parameters when combined with other constraints. For Omega_m=0.4,
Omega_Lam=0.6, and inflationary index n=1, the shape Gamma at z=0 =
0.12^+0.05_-0.06 (h^-1mpc)^-1. Matching the observed cluster mass function in
flat models requires Omega_m= 0.50^+0.13_-0.10 for Gamma=0.15, and higher
Omega_m for larger Gamma. A COBE-normalized model with Omega_m=0.4,
Omega_Lam=0.6, h=0.65, Omega_b h^2=0.02 requires n=0.91+/-0.03 for a tensor
normalization T/S=7(1-n). A better determination of the mean opacity of the Lya
forest would increase the precision of our P(k) measurement and remove the main
source of systematic uncertainty.(Abridged)

</DOC>
<DOC>
<DOCNO> 101651 </DOCNO>
An analogous of Jouanolou's Theorem in positive characteristic


  We show that a generic vector field on an affine space of positive
characteristic admits an invariant algebraic hypersurface. This contrast with
Jouanolou's Theorem that shows that in characteristic zero the situation is
completely opposite. That is a generic vector field in the complex plane does
not admit any invariant algebraic curve.

</DOC>
<DOC>
<DOCNO> 40412 </DOCNO>
Measurements of the bottom quark mass


  I will review new measurements of the b quark mass, presented at this
conference by ALEPH and DELPHI. A large set of observables has been used and
detailed studies on jet algorithms have been performed. These measurements at
the Z peak are consistent with the results obtained at the Upsilon scale when
assuming the running of the b quark mass as predicted by perturbative QCD.

</DOC>
<DOC>
<DOCNO> 170781 </DOCNO>
Liquid state NMR Quantum Computing


  This in an introduction on quantum computing and on the use of NMR to build
quantum computers, geared towards an NMR audience.

</DOC>
<DOC>
<DOCNO> 70727 </DOCNO>
Hidden Sector Gaugino Condensation and the Observable World


  We study the phenomenology of a class of models describing modular invariant
gaugino condensation in the hidden sector of a low-energy effective theory
derived from the heterotic string. Placing simple demands on the resulting
observable sector - such as proper electroweak symmetry-breaking, superpartner
spectra consistent with current limits and neutralino relic densities of an
acceptable magnitude - results in significant restrictions on the possible
configurations of the hidden sector.

</DOC>
<DOC>
<DOCNO> 174597 </DOCNO>
Antimatter and Matter Production in Heavy Ion Collisions at CERN (The


  Besides the dedicated search for strangelets NA52 measures light
(anti)particle and (anti)nuclei production over a wide range of rapidity.
Compared to previous runs the statistics has been increased in the 1998 run by
more than one order of magnitude for negatively charged objects at different
spectrometer rigidities. Together with previous data taking at a rigidity of
-20 GeV/c we obtained 10^6 antiprotons 10^3 antideuterons and two antihelium3
without centrality requirements. We measured nuclei and antinuclei
(p,d,antiprotons, antideuterons) near midrapidity covering an impact parameter
range of b=2-12 fm. Our results strongly indicate that nuclei and antinuclei
are mainly produced via the coalescence mechanism. However the centrality
dependence of the antibaryon to baryon ratios show that antibaryons are
diminished due to annihilation and breakup reactions in the hadron dense
environment. The volume of the particle source extracted from coalescence
models agrees with results from pion interferometry for an expanding source.
The chemical and thermal freeze-out of nuclei and antinuclei appear to coincide
with each other and with the thermal freeze-out of hadrons.

</DOC>
<DOC>
<DOCNO> 99288 </DOCNO>
Mirror symmetry and actions of braid groups on derived categories


  Talk given at Harvard, January 1999, published in the Proceedings of the
Harvard Winter School on mirror symmetry, vector bundles and lagrangian cycles,
1999, International Press. Surveys the joint work [ST, KS] with Paul Seidel and
Mikhail Khovanov.

</DOC>
<DOC>
<DOCNO> 13944 </DOCNO>
Phase transition in a magnetic field in V2-yO3 (y=0 and 0.04)


  The effect of a magnetic field on the two long-range-ordered magnetic phases,
the collinear insulating antiferromagnetic (AFI) and the incommensurate
metallic transverse spin density wave (SDW), is investigated for the vanadium
sesquioxide system. A field of 18 T has little effect on the AFI phase of a
nominal V2O3 sample. The transverse SDW phase of V1.96O3 can be suppressed by a
4.6(3)-T magnetic field applied in the plane of spiraling spins, while the same
magnetic field applied along the spiral axis has little effect on the SDW
phase.

</DOC>
<DOC>
<DOCNO> 119847 </DOCNO>
High-energy $\gamma$-ray emission from GRBs


  GRBs are nowadays a rather well understood phenomenon in the soft (KeV-MeV)
$\gamma$-ray energy band, while only a few GRBs have been observed at high
photon energies ($E_{\gamma} \ut > 1$ GeV). It is also widely recognized that
GRBs accelerate protons to relativistic energies and that dense media are often
present nearby the sources. Within this framework we compute in detail the
high-energy $\gamma$-ray flux from the decay of neutral pions produced through
the interaction of accelerate protons with nucleons in the surrounding medium.
We also take into account the local and intergalactic $\gamma$-ray absorption.
The presence of magnetic fields around the GRB sources causes the deflection of
the accelerated protons and so a temporal spread of the produced high-energy
$\gamma$-rays with respect to the signal in the soft $\gamma$-ray band.
Moreover, we analyze the possibility to detect the $\gamma$-ray signal in the
GeV-TeV energy range by the ARGO detector under construction in Tibet.

</DOC>
<DOC>
<DOCNO> 85162 </DOCNO>
Fundamental units of length and time


  Ideal rods and clocks are defined as an infinitesimal symmetry of the
spacetime. Since no a priori geometric structure is considered, all the
possible models of spacetime are obtained.

</DOC>
<DOC>
<DOCNO> 119437 </DOCNO>
The Global Cosmological Parameters


  This lecture note presents a survey of the current status of the
determination of the three cosmological parameters, the Hubble constant, the
mass density paramater and the cosmological constant, to the closing date of
the end of November 1999.

</DOC>
<DOC>
<DOCNO> 71391 </DOCNO>
Yang--Mills duality as origin of generations, quark mixing and neutrino


  The origin of fermion generations is one of the great mysteries in particle
physics. We consider here a possible solution within the Standard Model
framework based on a nonabelian generalization of electric-magnetic duality.
First, nonabelian duality says that dual to the colour (electric) symmetry
SU(3), there is a ``colour magnetic symmetry'' $\widetilde{SU}(3)$, which by a
result of 't~Hooft is spontaneously broken and can thus play the role of the
"horizontal symmetry" of generations. Second, nonabelian duality suggests the
manner this symmetry is broken with frame vectors in internal symmetry space
acting as Higgs fields. As a result, mass matrices factorize leading to fermion
mass hierarchy. A calculation to first order gives mixing (CKM and MNS)
matrices in general agreement with experiment. In particular, quark mixing is
seen naturally to be weak compared with leptons, while within the lepton
sector, $\mu-\tau$ mixing turns out near maximal but $e-\tau$ mixing small,
just as seen in recent $\nu$ oscillation experiments. In addition, the scheme
leads to many testable predictions ranging from rare FCNC meson decays and
$\mu-e$ conversion in nuclei to cosmic ray air showers above $10^{20}$ eV.

</DOC>
<DOC>
<DOCNO> 9960 </DOCNO>
Dynamical Charge Susceptibility of the Spinless Falicov-Kimball Model


  An exact solution is presented for the frequency-dependent charge
susceptibility of the spinless Falicov-Kimball model by using dynamical
mean-field theory. We develop a nontrivial application of the Baym-Kadanoff
"conserving approximation" formalism to exactly determine the
frequency-dependent vertex function (which turns out to assume a particularly
simple form). We show how the static and dynamic susceptibilities are decoupled
in this model and how the dynamic susceptibility generically does not show any
signal of the low-temperature charge-density-wave phase transition. We also
examine the temperature evolution of the dynamic charge susceptibility for the
special case of half-filling.

</DOC>
<DOC>
<DOCNO> 170102 </DOCNO>
Delocalized Qubits as a Computational Basis in the System of Interacting


  It is suggested to map the qubits into solid state NMR spin system collective
states instead of the states of the individual spin. Such an approach
introduces the stable computational basis without any additional actions and
allows to obtain the universal set of quantum gates, which operation time is
determined only by a RF pulse duration.

</DOC>
<DOC>
<DOCNO> 99519 </DOCNO>
Lie Methods in Growth of Groups and Groups of Finite Width


  In the first, mostly expository, part of this paper, a graded Lie algebra is
associated to every group G given with an N-series of subgroups. The
asymptotics of the Poincare series of this algebra give estimates on the growth
of the group G. This establishes the existence of a gap between polynomial
growth and growth of type $e^{\sqrt n}$ in the class of residually-p groups,
and gives examples of finitely generated p-groups of uniformly exponential
growth. In the second part, we produce two examples of groups of finite width
and describe their Lie algebras, introducing a notion of Cayley graph for
graded Lie algebras. We compute explicitly their lower central and dimensional
series, and outline a general method applicable to some other groups from the
class of branch groups. These examples produce counterexamples to a conjecture
on the structure of just-infinite groups of finite width.

</DOC>
<DOC>
<DOCNO> 71168 </DOCNO>
Energy-momentum uncertainties as possible origin of threshold anomalies


  A threshold anomaly refers to a theoretically expected energy threshold that
is not observed experimentally. Here we offer an explanation of the threshold
anomalies encountered in the ultra-high energy cosmic ray events and the
TeV-gamma ray events, by arguing that energy-momentum uncertainties due to
quantum gravity, too small to be detected in low-energy regime, can affect
particle kinematics so as to raise or even eliminate the energy thresholds. A
possible modification of the energy-momentum dispersion relation, giving rise
to time-of-flight differences between photons of different energies from gamma
ray bursts, is also discussed.

</DOC>
<DOC>
<DOCNO> 12249 </DOCNO>
Study Notes on Numerical Solutions of the Wave Equation with the Finite


  In this introductory work I will present the Finite Difference method for
hyperbolic equations, focusing on a method which has second order precision
both in time and space (the so-called staggered leapfrog method) and applying
it to the case of the 1d and 2d wave equation. A brief derivation of the energy
and equation of motion of a wave is done before the numerical part in order to
make the transition from the continuum to the lattice clearer. To illustrate
the extension of the method to more complex equations, I also add dissipative
terms of the kind $-\eta \dot{u}$ into the equations. The von Neumann numerical
stability analysis and the Courant criterion, two of the most popular in the
literature, are briefly discussed. In the end I present some numerical results
obtained with the leapfrog algorithm, illustrating the importance of the
lattice resolution through energy plots.

</DOC>
<DOC>
<DOCNO> 117459 </DOCNO>
A Preliminary Visual Orbit of BY Draconis


  We report on the preliminary determination of the visual orbit of the
double-lined spectroscopic binary system BY Draconis with data obtained by the
Palomar Testbed Interferometer in 1999. BY Dra is a nearly equal-mass
double-lined binary system whose spectroscopic orbit is well known. We have
estimated the visual orbit of BY Dra from our interferometric visibility data
fit both separately and in conjunction with archival radial velocity data. Our
BY Dra orbit is in good agreement with the spectroscopic results. Due to the
orbit's face-on orientation, the physical parameters implied by a combined fit
to our visibility data and radial velocity data do not yet result in precise
component masses and a system distance, but with continued interferometric
monitoring we hope to improve the mass estimates to better than 10%
determinations.

</DOC>
<DOC>
<DOCNO> 100304 </DOCNO>
A New Cohomology Theory for Orbifold


  Motivated by orbifold string theory, we introduce orbifold cohomology group
for any almost complex orbifold and orbifold Dolbeault cohomology for any
complex orbifold. Then, we show that our new cohomology group satisfies
Poincare duality and has a natural ring structure. Some examples of orbifold
cohomology ring are computed.

</DOC>
<DOC>
<DOCNO> 80890 </DOCNO>
The role of Monte Carlo within a diagonalization/Monte Carlo scheme


  We review the method of stochastic error correction which eliminates the
truncation error associated with any subspace diagonalization. Monte Carlo
sampling is used to compute the contribution of the remaining basis vectors not
included in the initial diagonalization. The method is part of a new approach
to computational quantum physics which combines both diagonalization and Monte
Carlo techniques.

</DOC>
<DOC>
<DOCNO> 102075 </DOCNO>
Fast Evaluation, Weights and Nonlinearity of Rotation-Symmetric


  We study the nonlinearity and the weight of the rotation-symmetric (RotS)
functions defined by Pieprzyk and Qu. We give exact results for the
nonlinearity and weight of 2-degree RotS functions with the help of the
semi-bent functions and we give the generating function for the weight of the
3-degree RotS function. Based on the numerical examples and our observations we
state a conjecture on the nonlinearity and weight of the 3-degree RotS
functions.

</DOC>
<DOC>
<DOCNO> 8196 </DOCNO>
Skyrmions in spinor Bose-Einstein condensates


  We show that spinor Bose-Einstein condensates not only have line-like vortex
excitations, but in general also allow for point-like topological excitations,
i.e., skyrmions. We discuss the static and dynamic properties of these
skyrmions for spin-1/2 and ferromagnetic spin-1 Bose gases.

</DOC>
<DOC>
<DOCNO> 120001 </DOCNO>
Blank Field X-Ray Sources


  The X-ray sky is not as well known as is sometimes thought. We report on our
search of minority populations (Kim & Elvis 1999). One of the most intriguing
is that of `blank field sources', i.e. bright ROSAT sources (F(X)>1e-13
erg/cm2/s) with no optical counterpart on the Palomar Sky Survey (to O=21.5)
within their 39"(99%) radius error circle. The nature of Blank Field sources is
unknown: no known extragalactic population has such extreme X-ray to optical
ratios (f(X)/f(V) >60). Moreover blank field source tend to have much flatter
PSPC spectra compared to radio-quiet AGN. Both properties suggest obscuration.
`Blank field sources' could be: Quasar-2s, low-mass AGNs, isolated neutron
stars, high redshift clusters of galaxies, failed clusters, AGNs with no big
blue bump. Identification with any of these populations would be an interesting
discovery.

</DOC>
<DOC>
<DOCNO> 152442 </DOCNO>
On Metric Perturbations in Brane-World Scenarios


  In this note we reconsider linearised metric perturbations in the one-brane
Randall-Sundrum Model. We present a simple formalism to describe metric
perturbations caused by matter perturbations on the brane and remedy some
misconceptions concerning the constraints imposed on the metric and matter
perturbations by the presence of the brane.

</DOC>
<DOC>
<DOCNO> 70484 </DOCNO>
Contribution of sigma meson pole to K_L-K_S mass difference


  The hypothesis of sigma meson pole dominance in the Delta I = 1/2 K -> pi pi
amplitudes is tested by using the K_L-K_S mass difference.

</DOC>
<DOC>
<DOCNO> 69111 </DOCNO>
Pion Cloud and Nucleon Mass in Finite Nuclei


  We study the mass of a nucleon in a nucleus using a model recently introduced
for a nucleon current with a pion cloud component. The method of QCD sum rules
is used to determine the mass shifts for nucleons to first order in nuclear
density in oxygen-16 and calcium-40, with the pion propagator determined by an
optical potential for pion-nucleus scattering. Mass shifts due to the pionic
contributions range from negligible in oxygen to -100 MeV in calcium at central
nuclear density, with larger shifts in the nuclear surface. The consistency of
this model with chiral perturbation theory is demonstrated.

</DOC>
<DOC>
<DOCNO> 68080 </DOCNO>
Do Stops Slow Down Electroweak Bubble Walls?


  We compute the wall velocity in the MSSM. We therefore generalize the SM
equations of motion for bubble walls moving through a hot plasma at the
electroweak phase transition and calculate the friction terms which describe
the viscosity of the plasma. We give the general expressions and apply them to
a simple model where stops, tops and W bosons contribute to the friction. In a
wide range of parameters including those which fulfil the requirements of
baryogenesis we find a wall velocity of order $v_w\approx 10^{-2}$ much below
the SM value.

</DOC>
<DOC>
<DOCNO> 7985 </DOCNO>
Double exchange-driven spin pairing at the (001) surface of manganites


  The (001) surface of La_{1-x}Ca_xMnO_3 system in various magnetic orderings
is studied by first principle calculations. A general occurrence is that z^2
dangling bond charge -- which is ``invisible'' in the formal valence picture --
is promoted to the bulk gap/Fermi level region. This drives a
double-exchange-like process that serves to align the surface Mn spin with its
subsurface neighbor, regardless of the bulk magnetic order. For heavy doping,
the locally ``ferromagnetic'' coupling is very strong and the moment enhanced
by as much as 30% over the bulk value.

</DOC>
<DOC>
<DOCNO> 117543 </DOCNO>
Wind properties of Wolf-Rayet stars at low metallicity: Sk41 (SMC)


  The stellar properties of Sk41 (AB4, WN5h), the only known single Wolf-Rayet
star in the SMC, are derived from ultraviolet (IUE), optical (AAT) and near-IR
(NTT) spectroscopy. Contrary to expectations, the stellar properties of Sk41
are typical of equivalent WN stars in the Galaxy and LMC, with T=42kK,
log(L/Lo)=5.7, v_inf=1300 km/s, Mdot/sqrt(f)=3x10^-5 Mo/yr and H/He=2 by
number, where f is the volume filling factor. The stellar luminosity of Sk41 is
50% below the minimum value predicted by single star evolutionary models at the
metallicity of the SMC.
  Emission line luminosities of HeII 4686A and CIV 5801-12A in SMC WR stars are
not systematically lower than their Galactic and LMC counterparts. From 43
late-type and 59 early-type WN stars, log L(HeII)=36.0 erg/s and 35.8 erg/s
respectively, while log L(CIV)=36.5 erg/s from 25 early-type WC stars. This new
calibration has application in deriving WR populations in young starburst
galaxies.
  Synthetic WN models are calculated with identical parameters except that
metal abundances are varied. Following the Smith et al. WN classification
scheme, CNO equilibrium models reveal that earlier spectral types are predicted
at lower metallicity, i.e. WN3--4 at 0.04 Z(solar) versus WN6 at 1.0 Z(solar).
This provides an explanation for the trend towards earlier WN spectral types at
low metallicity.

</DOC>
<DOC>
<DOCNO> 152608 </DOCNO>
Generalised scalar particle quantisation in 1+1 dimensions and


  The exceptional superalgebra $\D21a$ has been classified as a candidate
conformal supersymmetry algera in two dimensions. We propose an alternative
interpretation of it as an extended BFV-BRST quantisation superalgebra in 2D
($D(2,1;1) \simeq osp(2,2|2)$). A superfield realization is presented wherein
the standard extended phase space coordinates can be identified. The physical
states are studied via the cohomology of the BRST operator. Finally we reverse
engineer a classical action corresponding to the algebraic model we have
constructed, and identify the Lagrangian equations of motion.

</DOC>
<DOC>
<DOCNO> 120746 </DOCNO>
Limits on the Abundance of Galactic Planets From Five Years of Planet


  We search for signatures of planets in 43 intensively monitored microlensing
events that were observed between 1995 and 1999. Planets would be expected to
cause a short duration (~1 day) deviation on the smooth, symmetric light curve
produced by a single-lens. We find no such anomalies and infer that less than
1/3 of the ~0.3 M_sun stars that typically comprise the lens population have
Jupiter-mass companions with semi-major axes in the range of 1.5 AU <a < 4 AU.
Since orbital periods of planets at these radii are 3-15 years, the outer
portion of this region is currently difficult to probe with any other
technique.

</DOC>
<DOC>
<DOCNO> 117008 </DOCNO>
Integral methods for shallow free-surface flows with separation


  We study laminar thin film flows with large distortions in the free surface
using the method of averaging across the flow. Two concrete problems are
studied: the circular hydraulic jump and the flow down an inclined plane. For
the circular hydraulic jump our method is able to handle an internal eddy and
separated flow. Assuming a variable radial velocity profile like in
Karman-Pohlhausen's method, we obtain a system of two ordinary differential
equations for stationary states that can smoothly go through the jump where
previous studies encountered a singularity. Solutions of the system are in good
agreement with experiments. For the flow down an inclined plane we take a
similar approach and derive a simple model in which the velocity profile is not
restricted to a parabolic or self-similar form. Two types of solutions with
large surface distortions are found: solitary, kink-like propagating fronts,
obtained when the flow rate is suddenly changed, and stationary jumps,
obtained, e.g., behind a sluice gate. We then include time-dependence in the
model to study stability of these waves. This allows us to distinguish between
sub- and supercritical flows by calculating dispersion relations for
wavelengths of the order of the width of the layer.

</DOC>
<DOC>
<DOCNO> 13406 </DOCNO>
Quantum phases in an optical lattice


  We present the zero-temperature phase diagram of bosonic atoms in an optical
lattice, using two different mean-field approaches. The phase diagram consists
of various insulating phases and a superfluid phase. We explore the nature of
the insulating phase by calculating both the quasiparticle and quasihole
dispersion relation. We also determine the parameters of our single band
Bose-Hubbard model in terms of the microscopic parameters of the atoms in the
optical lattice.

</DOC>
<DOC>
<DOCNO> 119359 </DOCNO>
The jet of 3C 273 observed with ROSAT HRI


  ROSAT HRI observations of 3C 273 reveal X-ray emission all along the
optically visible jet with the peak of emission at the inner end. Whereas the
X-ray emission from the innermost knot A is consistent with a continuation of
the radio-to-optical synchrotron continuum, a second population of particles
with higher maximum energy has to be invoked to explain the X-ray emission from
knots B, C and D in terms of synchrotron radiation. Inverse Compton emission
could account for the X-ray flux from the hot spot. We detect a faint X-ray
halo with a characteristic scale of 29 kpc and particle density on the order of
6 x 10^4 m^-3, higher than previously thought.

</DOC>
<DOC>
<DOCNO> 10097 </DOCNO>
Caught Active Walkers


  A discrete implementation on a lattice of the Active Walker Model is
presented. After the model's validity is shown in simple simulations, more
complex simulations of walkers passing consecutively a lattice from an
arbitrary starting point at the left border to a random destination on the
right border are presented. It is found that walkers may be caught at a certain
position by bouncing back and forth between two contiguous lattice sites. The
statistical characteristics of this catchment effect are being studied. The
probability distribution of the number of walkers having passed the lattice
before the catchment occurred shows a exponential decrease to higher numbers.
Furthermore, the influence of some parameters of the model on the catchment
phenomenon is discussed. Position and height of the maxima of these
distributions show a linear dependency on a parameter.

</DOC>
<DOC>
<DOCNO> 11865 </DOCNO>
Influence of solvent granularity on the effective interaction between


  We study the effect of solvent granularity on the effective force between two
charged colloidal particles by computer simulations of the primitive model of
strongly asymmetric electrolytes with an explicitly added hard sphere solvent.
Apart from molecular oscillating forces for nearly touching colloids which
arise from solvent and counterion layering, the counterions are attracted
towards the colloidal surfaces by solvent depletion providing a simple
statistical description of hydration. This, in turn, has an important influence
on the effective forces for larger distances which are considerably reduced as
compared to the prediction based on the primitive model. When these forces are
repulsive, the long-distance behaviour can be described by an effective Yukawa
pair potential with a solvent-renormalized charge. As a function of colloidal
volume fraction and added salt concentration, this solvent-renormalized charge
behaves qualitatively similar to that obtained via the Poisson-Boltzmann cell
model but there are quantitative differences. For divalent counterions and
nano-sized colloids, on the other hand, the hydration may lead to overscreened
colloids with mutual attraction while the primitive model yields repulsive
forces. All these new effects can be accounted for through a solvent-averaged
primitive model (SPM) which is obtained from the full model by integrating out
the solvent degrees of freedom. The SPM was used to access larger colloidal
particles without simulating the solvent explicitly.

</DOC>
<DOC>
<DOCNO> 100153 </DOCNO>
Quadratic forms of rank 1, closed zones and laminae


  For a given lattice, we establish an equivalence involving a closed zone of
the corresponding Voronoi polytope, a lamina hyperplane of the corresponding
Delaunay partition and a quadratic form of rank 1 being an extreme ray of the
corresponding L-type domain.

</DOC>
<DOC>
<DOCNO> 7737 </DOCNO>
Multifractality of entangled random walks and non-uniform hyperbolic


  Multifractal properties of the distribution of topological invariants for a
model of trajectories randomly entangled with a nonsymmetric lattice of
obstacles are investigated. Using the equivalence of the model to random walks
on a locally nonsymmetric tree, statistical properties of topological
invariants, such as drift and return probabilities, have been studied by means
of a renormalization group (RG) technique. The comparison of the analytical
RG--results with numerical simulations as well as with the rigorous results of
P.Gerl and W.Woess demonstrates clearly the validity of our approach. It is
shown explicitly by direct counting for the discrete version of the model and
by conformal methods for the continuous version that multifractality occurs
when local uniformity of the phase space (which has an exponentially large
number of states) has been broken.

</DOC>
<DOC>
<DOCNO> 169984 </DOCNO>
Isotropic phase squeezing and the arrow of time


  We prove that isotropic squeezing of the phase is equivalent to reversing the
arrow of time.

</DOC>
<DOC>
<DOCNO> 121791 </DOCNO>
The Broken Light Curves of Gamma-Ray Bursts GRB 990123 and GRB 990510


  We have collected all of the published photometry for GRB 990123 and GRB
990510, the first two gamma-ray bursts where breaks were seen in the light
curves of their optical afterglows, and determined the shapes of their light
curves and the break times. These parameters were used to investigate the
physical mechanisms responsible for the breaks and the nature of the ambient
medium that the bursts occurred in. The light curve for GRB 990123 is best fit
by a broken power law with a break 1.68 +/- 0.19 days after the burst, a slope
of alpha1 = -1.12 +/- 0.08 before the break, and a slope of alpha2 = -1.69 +/-
0.06 after the break. This is consistent with a collimated outflow with a fixed
opening angle (theta0) of approximately five degrees. In this case the break in
the light curve is due to the relativistic fireball slowing to a gamma factor
of approximately 1 / theta0. The light curve for GRB 990510 is best fit by a
continuous function with an early-time slope of alpha1 = -0.54 +/- 0.14, a
late-time slope of alpha2 = -1.98 +/- 0.19, and a slow transition between the
two regimes approximately one day after the burst. This is consistent with a
collimated outflow with an opening angle of approximately five degrees that is
initially radiative, but undergoes a sideways expansion that begins
approximately one day after the burst. This sideways expansion is responsible
for the slow break in the light curve.

</DOC>
<DOC>
<DOCNO> 13432 </DOCNO>
Variational method to study vortex matter in mesoscopic superconductors


  A simple variational model is proposed to analyze the superconducting state
in long cylindrical type-II superconductor placed in the external magnetic
field. In the framework of this model, it is possible to solve the
Ginzburg-Landau equations for the states with axially symmetric distributions
of the order parameter. Phase transitions between different superconducting
states are studied in the presence of external magnetic field and an
equilibrium phase diagram of thin cylinder is obtained. The lower critical
field of the cylindrical type-II superconductor with arbitrary values of radius
and Ginzburg-Landau parameter is found. The field dependence of the
magnetization of thin cylinder, which can carry several magnetic flux quanta,
is calculated.

</DOC>
<DOC>
<DOCNO> 100356 </DOCNO>
Vassiliev invariants of Legendrian, of transverse and framed knots in


  We show that for a large class of contact 3-manifolds the groups of Vassiliev
invariants of Legendrian and of framed knots are canonically isomorphic. As a
corollary, we obtain that the group of finite order Arnold's $J^+$-type
invariants of wave fronts on a surface $F$ is isomorphic to the group of
Vassiliev invariants of framed knots in the spherical cotangent bundle $ST^*F$
of $F$.
  On the other hand we construct the first examples of contact manifolds for
which Vassiliev invariants of Legendrian knots can distinguish Legendrian knots
that realize isotopic framed knots and are homotopic as Legendrian immersions.

</DOC>
<DOC>
<DOCNO> 68943 </DOCNO>
Hierarchical Majorana Scales in the Seesaw Model


  If the mixing angles in each of the seesaw sectors are all small, and the
neutrino masses are hierarchical, we study the conditions for large neutrino
mixing using triangular matrices. In particular, the implication of the
neutrino oscillation data for the mass hierarchy in the heavy Majorana sector
is examined, and the heavy Majorana scales are shown to depend sensitively on
the solar mixing angle.

</DOC>
<DOC>
<DOCNO> 8156 </DOCNO>
Magnetic quantization of electronic states in d-wave superconductors


  We derive a general quasiclassical approach for long-range magnetic-field
quantization effects in superconductors. The method is applied to superclean
d-wave superconductors in the mixed state. We study the delocalized states with
energies $\epsilon \gg \Delta_{0}\sqrt{H/H_{c2}}$. We find that the energy
spectrum consists of narrow energy bands whose centers are located at the
Landau levels calculated in absence of the vortex potential. We show that
transitions between the states belonging to the different Landau levels give
rise to resonances in the a.c. quasiparticle conductivity and in the a.c.
vortex friction.

</DOC>
<DOC>
<DOCNO> 151758 </DOCNO>
Survey of Two-Time Physics


  Two-time physics (2T) is a general reformulation of one-time physics (1T)
that displays previously unnoticed hidden symmetries in 1T dynamical systems
and establishes previously unknown duality type relations among them. This may
play a role in displaying the symmetries and constructing the dynamics of
little understood systems, such as M-theory. 2T physics describes various 1T
dynamical systems as different d-dimensional ``holographic'' views of the same
2T system in $d+2$ dimensions. The ``holography'' is due to gauge symmetries
that tend to reduce the number of effective dimensions. Different 1T evolutions
(i.e. different Hamiltonians) emerge from the same 2T theory when gauge fixing
is done with different embeddings of d dimensions inside d+2 dimensions. Thus,
in the 2T setting, the distinguished 1T which we call ``time'' is a gauge
dependent concept. The 2T action has also a global SO(d,2) symmetry in flat
spacetime, or a more general d+2 symmetry in curved spacetime, under which all
dimensions are on an equal footing. This symmetry is observable in many 1T
systems, but it remained unknown until discovered in the 2T formalism. 2T
physics has mainly been developed in the context of particles, including spin
and supersymmetry, but some advances have also been made with strings and
p-branes, and insights for M-theory have already emerged. In the case of
particles, there exists a general worldline formulation with background fields,
as well as a field theory formulation, both described in terms of fields that
depend on d+2 coordinates. The Standard Model of particle physics can be
regarded as a gauge fixed form of a 2T theory in 4+2 dimensions. These facts
already provide evidence for a new type of higher dimensional unification.

</DOC>
<DOC>
<DOCNO> 116790 </DOCNO>
Entanglement versus disentanglement: Quantum Cryptography


  In quantum information, the role of entanglement and disentanglement is
itself a subject of research and debate. Earlier works on quantum cryptography
have almost established that entanglement has no special advantage in quantum
cryptography. In this paper we reveal that entanglement is better ingredient
than disentanglement for our alternative quantum cryptography.

</DOC>
<DOC>
<DOCNO> 120857 </DOCNO>
Detection of a Compact X-ray Source in the Supernova Remnant G29.6+0.1:


  We present follow-up observations of the serendipitously discovered 7-s X-ray
pulsar AX J1845-0258, which displays characteristics similar to those observed
in the anomalous X-ray pulsars (AXPs). We find a dramatic reduction in its 3-10
keV flux in both new ASCA and RXTE datasets. Within the pulsar's position-error
locus, we detect a faint point source, AX J184453-025640, surrounded by an arc
of diffuse X-ray emission. This arc is coincident with the South-East quadrant
of the radio shell of the newly discovered supernova remnant G29.6+0.1,
reported in our companion paper (Gaensler et al. 1999). Lack of sufficient flux
from the source prevents us from confirming the 7-s pulsed emission observed in
the bright state; hence, at present we cannot definitively resolve whether AX
J1845-0258 and AX J184453-025640 are one and the same. If they are the same,
then the peak-to-peak luminosity changes recorded for AX J1845-0258 may be
larger than seen in other AXPs; closer monitoring of this pulsar might lead to
a resolution on the mechanism that drives AXPs.

</DOC>
<DOC>
<DOCNO> 83076 </DOCNO>
Computing large and small stable models


  In this paper, we focus on the problem of existence and computing of small
and large stable models. We show that for every fixed integer k, there is a
linear-time algorithm to decide the problem LSM (large stable models problem):
does a logic program P have a stable model of size at least |P|-k. In contrast,
we show that the problem SSM (small stable models problem) to decide whether a
logic program P has a stable model of size at most k is much harder. We present
two algorithms for this problem but their running time is given by polynomials
of order depending on k. We show that the problem SSM is fixed-parameter
intractable by demonstrating that it is W[2]-hard. This result implies that it
is unlikely, an algorithm exists to compute stable models of size at most k
that would run in time O(n^c), where c is a constant independent of k. We also
provide an upper bound on the fixed-parameter complexity of the problem SSM by
showing that it belongs to the class W[3].

</DOC>
<DOC>
<DOCNO> 70708 </DOCNO>
Skyrmion-anti-Skyrmion Annihilation with Omega Mesons


  We study numerically the annihilation of an omega-stabilized Skyrmion and an
anti-Skyrmion in three spatial dimensions. To our knowledge this is a first
successful simulation of Skyrmion-anti-Skyrmion annihilation which follows
through to the point where the energy is carried by outgoing meson waves.
  We encounter instabilities similar to those encountered is earlier
calculations, but in our case these are not fatal and we are able to simulate
through this process with a global energy loss of less than 8%, and to identify
robust features of the final radiation pattern. The system passes through a
singular configuration at the time of half-annihilation. This is followed by
the onset of fast oscillations which are superimposed on the smoother process
which leads to the appearence of outgoing spherical waves.
  We investigate the two prominent features of this process, the proliferation
of small, fast oscillations, and the singular intermediate configuration. We
find that our equations of motion allow for a regime in which the amplitude of
certain small perturbations increases exponentially. This regime is similar but
not identical to the situation pointed out earlier regarding the original
Skyrme model. We argue that the singularity may be seen as the result of a
pinch effect similar to that encountered in plasmas.

</DOC>
<DOC>
<DOCNO> 120591 </DOCNO>
On the Origin of the Rotation Curves of Dark-Matter-Dominated Galaxies


  Rotation curves of dark-matter-dominated galaxies measure the mass profiles
of galactic halos and thereby test theories of their cosmological origin. While
attention has focused lately on the possible discrepancy at small
galactocentric radii between observed rotation curves and the singular density
profiles predicted by N-body simulations of the Cold Dark Matter (CDM) model,
the observed rotation curves nevertheless contain valuable additional
information with which to test the theory and constrain the fundamental
cosmological parameters, despite this uncertainty at small radii.
 An analytical model we derived elsewhere for the postcollapse equilibrium of
cosmological halos as truncated, nonsingular, isothermal spheres (TIS)
reproduces many of the average properties of halos in CDM simulations to good
accuracy, including the density profiles outside the central region. The
circular velocity profile of this TIS model is, moreover, in excellent
agreement with the observed ones and yields the mass and formation epoch of an
observed halo from the parameters of its rotation curve. This allows us to
predict correlations amongst rotation curve parameters, such as the maximum
velocity and the radius at which it occurs, for different mass halos forming at
different epochs in the CDM model. As an example, we derive the observed
v_max-r_max relation analytically, with preference for the flat Lambda-CDM
model.

</DOC>
<DOC>
<DOCNO> 122045 </DOCNO>
Global VLBI Observations of Compact Radio Sources in M82


  Observations of the starburst galaxy, M82, have been made with a 20-station
global VLBI array at $\lambda$18cm. Maps are presented of the brightest young
supernova remnants (SNR) in M82 and the wide-field mapping techniques used in
making images over a field of view of $\sim$1 arcminute with 3 milliarcsecond
resolution are discussed. A limit has been placed on the power law deceleration
of the young SNR, 43.31+592 with an index greater than 0.73 $\pm$ 0.11 from
observations with the European VLBI Network. Using the global array we have
resolved compact knots of radio emission in the source which, with future
global observations, will enable better constraints to be placed on the
expansion parameters of this SNR.
  The latest global observations have also provided high resolution images of
the most compact radio source in M82, 41.95+575. We determine an upper limit to
the radial expansion rate along the major axis of 2000 km s$^{-1}$. However,
the new images also show structure resembling that of collimated ejection which
brings into question the previous explanation of the source as being due to the
confinement of a supernova by a high density circumstellar medium.
  It is apparent that we are now able to image the brightest supernova remnants
in M82 with a linear scale which allows direct comparison with galactic SNR
such as Cassiopeia A.

</DOC>
<DOC>
<DOCNO> 84209 </DOCNO>
On the structure of solutions to the static vacuum Einstein equations


  A complete characterization is obtained of the asymptotic behavior of
solutions of the static vacuum Einstein equations which have a (pseudo)-compact
horizon or boundary and are complete away from the boundary. It is proved that
the time-symmetric space-like hypersurface has only finitely many ends, each of
which is either asymptotically flat (AF) or parabolic, as in the (static)
Kasner metric. Examples are given with both types of behavior, together with an
extensive discussion and new characterization of Weyl metrics. The asymptotics
result allows one in most circumstances to drop the AF assumption from the
static black hole uniqueness theorems and replace it with just a completeness
assumption.

</DOC>
<DOC>
<DOCNO> 71274 </DOCNO>
Color coherent phenomena on nuclei and the QCD evolution equation


  We review the phenomenon of color coherence in quantum chromodynamics (QCD),
its implications for hard and soft processes with nuclei, and its experimental
manifestations. The relation of factorization theorems in QCD with color
coherence phenomena in deep inelastic scattering (DIS) and color coherence
phenomena in hard exclusive processes is emphasized. Analyzing numerically the
QCD evolution equation for conventional and skewed parton densities in nuclei,
we study the onset of generalized color transparency and nuclear shadowing of
the sea quark and gluon distributions in nuclei as well as related phenomena.
Such novel results as the dependence of the effective coherence length on $Q^2$
and general trends of the QCD evolution are discussed. The limits of the
applicability of the QCD evolution equation at small Bjorken $x$ are estimated
by comparing the inelastic quark-antiquark- and two gluon-nucleon (nucleus)
cross sections, calculated within the DGLAP approximation, with the dynamical
boundaries, which follow from the unitarity of the $S$ matrix for purely QCD
interactions. We also demonstrate that principles of color coherence play an
important role in the processes of soft diffraction off nuclei.

</DOC>
<DOC>
<DOCNO> 100579 </DOCNO>
Group representations and the Euler characteristic of elliptically


  To every elliptic Calabi-Yau threefold with a section $X$ there can be
associated a Lie group $G$ and a representation $\rho$ of that group. The group
is determined from the Weierstrass model, which has singularities that are
generically rational double points; these double points lead to local factors
of $G$ which are either the corresponding A-D-E groups or some associated
non-simply laced groups.
  The representation $\rho$ is a sum of representations coming from the local
factors of $G$, and of other representations which can be associated to the
points at which the singularities are worse than generic.
  This construction first arose in physics, and the requirement of anomaly
cancellation in the associated physical theory makes some surprising
predictions about the connection between $X$ and $\rho$. In particular, an
explicit formula (in terms of $\rho$) for the Euler characteristic of $X$ is
predicted. We give a purely mathematical proof of that formula in this paper,
introducing along the way a new invariant of elliptic Calabi-Yau threefolds.
We also verify the other geometric predictions which are consequences of
anomaly cancellation, under some (mild) hypotheses about the types of
singularities which occur.
  As a byproduct we also discover a novel relation between the Coxeter number
and the rank in the case of the simply laced groups in the ``exceptional
series'' studied by Deligne.

</DOC>
<DOC>
<DOCNO> 14132 </DOCNO>
First order transition from antiferromagnetism to ferromagnetism in


  Results of dc magnetization study are presented showing interesting
thermomagnetic history effects across the antiferromagnetic to ferromagnetic
transition in Ce(Fe$_{0.96}$Al$_{0.04})_2$. Specifically, we observe
(i)ZFC/FC irreversibility rising with increasing field; (ii) virgin curve lying
outside the envelope M-H curve. We argue that these effects are quite different
from the characteristics seen in spin-glasses or in hard ferromagnets; they can
be understood as metastabilities associated with a first order magnetic phase
transition.

</DOC>
<DOC>
<DOCNO> 120086 </DOCNO>
Enrichment of the Intergalactic Medium by Radiation Pressure Driven Dust


  The presence of metals in hot cluster gas and in Ly-alpha absorbers, as well
as the mass-metallicity relation of observed galaxies, suggest that galaxies
lose a significant fraction of their metals to the intergalactic medium (IGM).
Theoretical studies of this process have concentrated on metal removal by
dynamical processes or supernova-driven winds. Here, we investigate the
enrichment of the IGM by the expulsion of dust grains from galaxies by
radiation pressure. We use already completed cosmological simulations, to which
we add dust assuming that most dust can reach the equilibrium point between
radiation pressure and gravitational forces. We find that the expulsion of dust
and its subsequent (partial) destruction in the IGM can plausibly account for
the observed level of C and Si enrichment of the z=3 IGM. At low-z, dust
ejection and destruction could explain a substantial fraction of the metals in
clusters, but it cannot account for all of the chemical species observed. Dust
expelled by radiation pressure could give clusters a visual opacity of up to
0.2-0.5 mag in their central regions even after destruction by the hot
intracluster medium; this value is interestingly close to limits and claimed
observations of cluster extinction. We also comment on the implications of our
results for the opacity of the general IGM. Finally, we suggest a possible
`hybrid' scenario in which winds expel gas and dust into galaxy halos but
radiation pressure distributes the dust uniformly through the IGM.

</DOC>
<DOC>
<DOCNO> 85539 </DOCNO>
Extended Kelvin theorem in relativistic magnetohydrodynamics


  We prove the existence of a generalization of Kelvin's circulation theorem in
general relativity which is applicable to perfect isentropic
magnetohydrodynamic flow. The argument is based on a new version of the
Lagrangian for perfect magnetohydrodynamics. We illustrate the new conserved
circulation with the example of a relativistic magnetohydrodynamic flow
possessing three symmetries.

</DOC>
<DOC>
<DOCNO> 13497 </DOCNO>
Complexity and fragility in ecological networks


  A detailed analysis of three species-rich ecosystem food webs has shown that
they display scale-free distributions of connections. Such graphs of
interaction are in fact shared by a number of biological and technological
networks, which have been shown to display a very high homeostasis against
random removals of nodes. Here we analyse the response of these ecological
graphs to both random and selective perturbations (directed to most connected
species). Our results suggest that ecological networks are extremely robust
against random removal but very fragile when selective attacks are used. These
observations can have important consequences for biodiversity dynamics and
conservation issues, current estimations of extinction rates and the relevance
and definition of keystone species.

</DOC>
<DOC>
<DOCNO> 39927 </DOCNO>
Improved Experimental Limits on the Production of Magnetic Monopoles


  We present new limits on low mass accelerator-produced point-like Dirac
magnetic monopoles trapped and bound in matter surrounding the D\O collision
region of the Tevatron at Fermilab (experiment E-882). In the context of a
Drell-Yan mechanism, we obtain cross section limits for the production of
monopoles with magnetic charge values of 1, 2, 3, and 6 times the minimum Dirac
charge of the order of picobarns, some hundred times smaller than found in
similar previous Fermilab searches. Mass limits inferred from these cross
section limits are presented.

</DOC>
<DOC>
<DOCNO> 100461 </DOCNO>
Lie algebras associated to fiber-type arrangements


  Given a hyperplane arrangement in a complex vector space of dimension n,
there is a natural associated arrangement of codimension k subspaces in a
complex vector space of dimension k*n. Topological invariants of the complement
of this subspace arrangement are related to those of the complement of the
original hyperplane arrangement. In particular, if the hyperplane arrangement
is fiber-type, then, apart from grading, the Lie algebra obtained from the
descending central series for the fundamental group of the complement of the
hyperplane arrangement is isomorphic to the Lie algebra of primitive elements
in the homology of the loop space for the complement of the associated subspace
arrangement. Furthermore, this last Lie algebra is given by the homotopy groups
modulo torsion of the loop space of the complement of the subspace arrangement.
Looping further yields an associated Poisson algebra, and generalizations of
the "universal infinitesimal Poisson braid relations."

</DOC>
<DOC>
<DOCNO> 123292 </DOCNO>
Deep-Imaging Observations of a Candidate of an Absorbed QSO at z=0.653,


  The results of deep-imaging observations of a candidate of an absorbed QSO at
z=0.653, AX J131831+3341, are presented. AX J131831+3341 was found during the
course of optical follow-up observations of the ASCA Large Sky Survey, and has
an X-ray luminosity of 10^{45} erg s^{-1} (2-10keV), which corresponds to those
of QSOs. Its optical spectrum shows no significant broad H_beta emission line,
suggesting that the object is an absorbed QSO. Deep R and V band images reveal
the presence of a point-like nucleus and an asymmetric extended component. The
nuclear component has a blue color, and the optical magnitude is much fainter
than that expected from the observed X-ray flux for typical type-1 AGNs. These
photometric properties and the presence of broad MgII 2800A emission can be
explained simultaneously if the observed nuclear light is dominated by
scattered nuclear light, though there is a possibility that the nuclear
component is a slightly absorbed nucleus if its intrinsic X-ray to optical flux
ratio is the largest among X-ray selected AGNs. The size of the extended
component, which is thought to be the host galaxy of the QSO, is larger than
those of normal disk galaxies at z=0-0.75, and the absolute magnitude is
similar to those of the brightest host galaxies of QSOs at redshifts smaller
than 0.5. The V-R and R-I colors of the component are consistent with a 1
Gyr-old stellar population model without absorption.

</DOC>
<DOC>
<DOCNO> 9987 </DOCNO>
Nonlinear acousto-electric transport in a two-dimensional electron


  We study both theoretically and experimentally the nonlinear interaction
between an intense surface acoustic wave and a two-dimensional electron plasma
in semiconductor-piezocrystal hybrid structures. The experiments on hybrid
systems exhibit strongly nonlinear acousto-electric effects. The plasma turns
into moving electron stripes, the acousto-electric current reaches its maximum,
and the sound absorption strongly decreases. To describe the nonlinear
phenomena, we develop a coupled-amplitude method for a two-dimensional system
in the strongly nonlinear regime of interaction. At low electron densities the
absorption coefficient decreases with increasing sound intensity, whereas at
high electron density the absorption coefficient is not a monotonous function
of the sound intensity. High-harmonic generation coefficients as a function of
the sound intensity have a nontrivial behavior. Theory and experiment are found
to be in a good agreement.

</DOC>
<DOC>
<DOCNO> 152445 </DOCNO>
Instanton amplitudes in open-closed topological string theory


  I use the universal instanton formalism to discuss quantum effects in the
open-closed topological string theory of a Calabi-Yau A-model, in the presence
of a multiply-wrapped `Floer' D-brane. This gives a precise meaning (up to the
issue of compactifying the relevant moduli spaces) to the instanton corrections
which affect sigma model and topological string amplitudes. The cohomological
formalism I use recovers the homological approach used by Fukaya and
collaborators in the singly-wrapped case, even though it is not a naive
generalization of the latter. I also prove some non-renormalization theorems
for amplitudes with low number of insertions. The non-renormalization argument
is purely geometric and based on the universal instanton formulation, and thus
it does not assume that the background satisfies the string equations of
motion. These results are valid even though the D-brane background typically
receives worldsheet instanton corrections. I also point out that the localized
form of the boundary BRST operator receives instanton corrections and make a
few comments on the consequences of this effect.

</DOC>
<DOC>
<DOCNO> 100195 </DOCNO>
Lattices, interpolation, and set theory


  We review a few results concerning interpolation of monotone functions on
infinite lattices, emphasizing the role of set-theoretic considerations.
  We also discuss a few open problems.

</DOC>
<DOC>
<DOCNO> 69704 </DOCNO>
A possible hadronic excess in psi(2S) decay and rho-pi puzzle


  We examine the so-called rho-pi puzzle of the psi(2S) decay by incorporating
two inputs: One is the relative phase between the one-photon and the gluon
decay amplitude, and the other is a possible anomaly in the inclusive
nonelectromagnetic decay rate of psi(2S). We propose the possibility that in
the psi(2S) decay a hadronic decay process of long distance origin is important
in addition to the short-distance decay process. The amplitude of this
additional process should nearly cancel the three-gluon amplitude in the
exclusive psi(2S)---> 1-0- and turn the sum dominantly real in contrast to the
J/psi decay. We present general consequences of this mechanism and then briefly
look into two models which possibly explain the course of this additional
amplitude. 

</DOC>
<DOC>
<DOCNO> 84758 </DOCNO>
Non-linear gravitational wave interactions with plasmas


  We consider the interactions of a strong gravitational wave with
electromagnetic fields using the 1+3 orthonormal tetrad formalism. A general
system of equations are derived, describing the influence of a plane fronted
parallel (pp) gravitational wave on a cold relativistic multi-component plasma.
We focus our attention on phenomena that are induced by terms that are higher
order in the gravitational wave amplitude. In particular, it is shown that
parametric excitations of plasma oscillations takes place, due to higher order
gravitational non-linearities. The implications of the results are discussed.

</DOC>
<DOC>
<DOCNO> 117024 </DOCNO>
Comments on "Effective Core Potentials" [M.Dolg, Modern Methods and


  The recent paper of M.Dolg is discussed and his critical remarks with respect
to the Generalized Relativistic Effective Core Potential (GRECP) method are
shown to be incorrect. Some main features of GRECP are discussed as compared
with the ``energy-consistent/adjusted'' pseudopotential and with the
conventional shape-consistent RECP.

</DOC>
<DOC>
<DOCNO> 8788 </DOCNO>
Structural Properties of the Sliding Columnar Phase in Layered Liquid


  Under appropriate conditions, mixtures of cationic and neutral lipids and DNA
in water condense into complexes in which DNA strands form local 2D smectic
lattices intercalated between lipid bilayer membranes in a lamellar stack.
These lamellar DNA-cationic-lipid complexes can in principle exhibit a variety
of equilibrium phases, including a columnar phase in which parallel DNA strands
from a 2D lattice, a nematic lamellar phase in which DNA strands align along a
common direction but exhibit no long-range positional order, and a possible new
intermediate phase, the sliding columnar (SC) phase, characterized by a
vanishing shear modulus for relative displacement of DNA lattices but a
nonvanishing modulus for compressing these lattices. We develop a model capable
of describing all phases and transitions among them and use it to calculate
structural properties of the sliding columnar phase. We calculate displacement
and density correlation functions and x-ray scattering intensities in this
phase and show, in particular, that density correlations within a layer have an
unusual $\exp(- {\rm const.} \ln^2 r)$ dependence on separation r. We
investigate the stability of the SC phase with respect to shear couplings
leading to the columnar phase and dislocation unbinding leading to the lamellar
nematic phase. For models with interactions only between nearest neighbor
planes, we conclude that the SC phase is not thermodynamically stable.
Correlation functions in the nematic lamellar phase, however, exhibit SC
behavior over a range of length scales

</DOC>
<DOC>
<DOCNO> 101605 </DOCNO>
The perturbation of the quantum Calogero-Moser-Sutherland system and


  The Hamiltonian of the trigonometric Calogero-Sutherland model coincides with
some limit of the Hamiltonian of the elliptic Calogero-Moser model. In other
words the elliptic Hamiltonian is a perturbed operator of the trigonometric
one. In this article we show the essential self-adjointness of the Hamiltonian
of the elliptic Calogero-Moser model and the regularity (convergence) of the
perturbation for the arbitrary root system. We also show the holomorphy of the
joint eigenfunctions of the commuting Hamiltonians w.r.t the variables (x_1,
>..., x_N) for the A_{N-1}-case. As a result, the algebraic calculation of the
perturbation is justified.

</DOC>
<DOC>
<DOCNO> 119677 </DOCNO>
The descendents of Lyman Break Galaxies in galaxy clusters: spatial


  We combine semi-analytical methods with a ultra-high resolution simulation
of a galaxy cluster (of mass 2.3 10^14h-1Msolar, and 4 10^6 particles within
its virial radius) formed in a standard CDM universe to study the spatial
distribution and orbital properties of the present-day descendents of Lyman
Break Galaxies (LBGs). At the present time only five (out of 12) of halos
containing LBGs survive as separate entities inside the cluster virial radius.
Their circular velocities are in the range 200 - 550 km/sec. Seven halos
merged together to form the central object at the very center of the cluster.
Using semi-analytical modeling of galaxy evolution we show that descendents of
halos containing LBGs now host giant elliptical galaxies. Galaxy orbits are
radial, with a pericenter to apocenter ratio of about 1:5. The orbital
eccentricities of LBGs descendents are statistically indistinguishable from
those of the average galaxy population inside the cluster, suggesting that the
orbits of these galaxies are not significantly affected by dynamical friction
decay after the formation of the cluster's main body. In this cluster, possibly
due to its early formation time, the descendents of LBGs are contained within
the central 60% of the cluster virial radius and have an orbital velocity
dispersion lower than the global galaxy population, originating a mild
luminosity segregation for the brightest cluster members. Mass estimates based
only on LBGs descendents (especially including the central cD) reflect this
bias in space and velocity and underestimate the total mass of this well
virialized cluster by up to a factor of two compared to estimates using at
least 20 cluster members.

</DOC>
<DOC>
<DOCNO> 12516 </DOCNO>
ABSSM - a new field-theoretic method of describing scattering/production


  A new relativistic field-theoretic formalism called "Asymptotic
Bethe-Salpeter State Method" (ABSSM) is presented, which allows to calculate
both electromagnetic formfactors and hadronic scattering and production
amplitudes of elementary and composite systems (being described by
Bethe-Salpeter amplitudes) within one theoretical framework. The ABSSM is then
applied to the deuteron as a composite system of two nucleons.

</DOC>
<DOC>
<DOCNO> 40021 </DOCNO>
Expected behaviour of different semiconductor materials in hadron fields


  The utilisation of semiconductor materials as detectors and devices operating
in high radiation environments, at the future particle colliders, in space
applications or in medicine and industry, necessitates to obtain radiation
harder materials. A systematic theoretical study has been performed,
investigating the interaction of charged hadrons with semiconductor materials
and the mechanisms of defect creation by irradiation. The mechanisms of the
primary interaction of the hadron with the nucleus of the semiconductor lattice
have been explicitly modelled and the Lindhard theory of the partition between
ionisation and displacements has been considered. The behaviour of silicon,
diamond, and some AIIIBV compounds, as GaAs, GaP, InP, InAs, InSb has been
investigated. The nuclear energy loss, and the concentration of primary defects
induced in the material bulk by the unit hadron fluence have been calculated.
The peculiarities of the proton and pion interactions as well as the specific
properties of the semiconductor material have been put in evidence.

</DOC>
<DOC>
<DOCNO> 178824 </DOCNO>
Quasideuteron configurations in 46V and 58Cu


  The data on low spin states in the odd-odd nuclei 46V and 58Cu investigated
with the 46Ti(p,ngamma)46V, 32S(16O,pn)46V and 58Ni(p,ngamma)58Cu reactions at
the FN-TANDEM accelerator in Cologne are reported. The states containing large
quasideuteron components are identified from the strong isovector M1
transitions, from shell model calculations and from experimental data for
low-lying states.

</DOC>
<DOC>
<DOCNO> 13575 </DOCNO>
Coherent stochastic resonance in one dimensional diffusion with one


  It is shown that the single-step periodic signal (periodic telegraph signal)
can not produce coherent stochastic resonance for diffusion on a segment with
one absorbing and one reflecting end points while the multi-step periodic
signal does. The general features of this process are exihibited. The resonant
frequency is found to decrease and the mean first passage time at resonant
frequency increases linearly, as we increase the length of the medium. The
cycle variable is shown to be the proper argument to express the first passage
time density function at resonance. A formula for first passage time density
function at resonance is derived in terms of two universal functions, which
clearly isolates its dependence on the length of the medium.

</DOC>
<DOC>
<DOCNO> 121858 </DOCNO>
The low surface brightness members of nearby groups


  We are undertaking a large, wide-field survey of nearby groups and poor
clusters. The main goals are identifying and characterizing the properties of
low-surface-brightness dwarf galaxies and determining the galaxy luminosity
function for M$_R > -17$. Large areas (typically 0.3--0.5 degree$^2$ per system
but up to 7 degree$^2$) of the groups Telescopium, Leo I, Dorado, N5575, HCG
42, HCG 44, HCG 68 and the poor clusters IC 4765 and Hydra have so far been
surveyed in V and I. We present the preliminary results for the photometric
study of the groups HCG 42, Telescopium (or NGC6868) and IC4765. Hundreds of
new low surface brightness galaxies are catalogued. Their spatial
distributions, colors, types and sizes will be studied as a function of the
richness of their environments.

</DOC>
<DOC>
<DOCNO> 170317 </DOCNO>
Generation of eigenstates using the phase-estimation algorithm


  The phase estimation algorithm is so named because it allows the estimation
of the eigenvalues associated with an operator. However it has been proposed
that the algorithm can also be used to generate eigenstates. Here we extend
this proposal for small quantum systems, identifying the conditions under which
the phase estimation algorithm can successfully generate eigenstates. We then
propose an implementation scheme based on an ion trap quantum computer. This
scheme allows us to illustrate two simple examples, one in which the algorithm
effectively generates eigenstates, and one in which it does not.

</DOC>
<DOC>
<DOCNO> 69101 </DOCNO>
Parton Distributions in Nuclei at Small x


  We study the nuclear shadowing effect in the context of Glauber-Gribov
multiple-scattering model and perturbative QCD. We find that at small x, the
$Q^2$ evolution of the shadowing is much slower than the DGLAP evolution, due
to the multiple scatterings at small x. We show that the gluon shadowing at
small x and for $Q^2 > 3GeV^2$ is perturbative in nature and does not depend on
the initial, non-perturbative condition. We evaluate the impact parameter
dependence of the gluon distribution and show that it is a non-linear effect in
the nuclear thickness function.

</DOC>
<DOC>
<DOCNO> 80791 </DOCNO>
Laplacian Center Vortices


  I present a unified picture of center vortices and Abelian monopoles. Both
appear as local gauge ambiguities in the Laplacian Center Gauge. This gauge is
constructed for a general SU(N) theory. Numerical evidence is presented, for
SU(2) and SU(3), that the projected $Z_N$ theory confines with a string tension
similar to the non-Abelian one.

</DOC>
<DOC>
<DOCNO> 152639 </DOCNO>
Non-Minimally Coupled Massive Scalar Field in a 2D Black Hole: Exactly


  We study a nonminimal massive scalar field in a 2-dimensional black hole
spacetime. We consider the black hole which is the solution of the 2d dilaton
gravity derived from string-theoretical models. We found an explicit solution
in a closed form for all modes and the Green function of the scalar field with
an arbitrary mass and a nonminimal coupling to the curvature. Greybody factors,
the Hawking radiation, and $ < \phi^2 >^{ren} $ are calculated explicitly for
this exactly solvable model.

</DOC>
<DOC>
<DOCNO> 80745 </DOCNO>
Fixed Point Gauge Actions with Fat Links: Scaling and Glueballs


  A new parametrization is introduced for the fixed point (FP) action in SU(3)
gauge theory using fat links. We investigate its scaling properties by means of
the static quark-antiquark potential and the dimensionless quantities $r_0 T_c,
T_c/\sqrt{\sigma}$ and $r_0 \sqrt{\sigma}$, where $T_c$ is the critical
temperature of the deconfining phase transition, $r_0$ is the hadronic scale
and $\sigma$ is the effective string tension. These quantities scale even on
lattices as coarse as $a \approx 0.3$ fm. We also measure the glueball spectrum
and obtain $m_{0^{++}}=1627(83)$ MeV and $m_{2^{++}}=2354(95)$ MeV for the
masses of the scalar and tensor glueballs, respectively.

</DOC>
<DOC>
<DOCNO> 151958 </DOCNO>
Logarithmic CFT on the Boundary and the World-Sheet


  The correspondences between logarithmic operators in the CFTs on the boundary
of AdS_3 and on the world-sheet and dipole fields in the bulk are studied using
the free field formulation of the SL(2,C)/SU(2) WZNW model. We find that
logarithmic operators on the boundary are related to operators on the
world-sheet which are in indecomposable representations of SL(2). The
Knizhnik-Zamolodchikov equation is used to determine the conditions for those
representations to appear in the operator product expansions of the model.

</DOC>
<DOC>
<DOCNO> 71581 </DOCNO>
Derivative expansion and gauge independence of the false vacuum decay


  In theories with radiative symmetry breaking, the calculation of the false
vacuum decay rate requires the inclusion of higher-order terms in the
derivative expansion of the effective action. I show here that, in the case of
covariant gauges, the presence of infrared singularities forbids the consistent
calculation by keeping the lowest-order terms. The situation is remedied,
however, in the case of $R_{\xi}$ gauges. Using the Nielsen identities I show
that the final result is gauge independent for generic values of the gauge
parameter $v$ that are not anomalously small.

</DOC>
<DOC>
<DOCNO> 10958 </DOCNO>
Computer simulations of liquid silica: equation of state and


  We conduct extensive molecular dynamics computer simulations of two models
for liquid silica [the model of Woodcock, Angell and Cheeseman, J. Phys. Chem.
65, 1565 (1976); and that of van Beest, Kramer and van Santen, Phys. Rev. Lett.
64, 1955, (1990)] to determine their thermodynamic properties at low
temperature T across a wide density range. We find for both models a wide range
of states in which isochores of the potential energy U are a linear function of
T^(3/5), as recently proposed for simple liquids [Rosenfeld and P. Tarazona,
Mol. Phys. 95, 141 (1998)]. We exploit this behavior to fit an accurate
equation of state to our thermodynamic data. Extrapolation of this equation of
state to low T predicts the occurrence of a liquid-liquid phase transition for
both models. We conduct simulations in the region of the predicted phase
transition, and confirm its existence by direct observation of phase separating
droplets of atoms with distinct local density and coordination environments.

</DOC>
<DOC>
<DOCNO> 7703 </DOCNO>
Critical behavior of frustrated systems: Monte Carlo simulations versus


  We study the critical behavior of frustrated systems by means of Pade-Borel
resummed three-loop renormalization-group expansions and numerical Monte Carlo
simulations. Amazingly, for six-component spins where the transition is second
order, both approaches disagree. This unusual situation is analyzed both from
the point of view of the convergence of the resummed series and from the
possible relevance of non perturbative effects.

</DOC>
<DOC>
<DOCNO> 117090 </DOCNO>
Apparent Superluminal Behavior


  The apparent superluminal propagation of electromagnetic signals seen in
recent experiments is shown to be the result of simple and robust properties of
relativistic field equations. Although the wave front of a signal passing
through a classically forbidden region can never move faster than light, an
attenuated replica of the signal is reproduced ``instantaneously'' on the other
side of the barrier. The reconstructed signal, causally connected to the
forerunner rather than the bulk of the input signal, appears to move through
the barrier faster than light.

</DOC>
<DOC>
<DOCNO> 116813 </DOCNO>
A Variational Approach in the Dissipative Nonlinear Schr\"{o}dinger


  The properties of pulse propagation in a nonlinear fiber including linear
damped term added in the usual nonlinear Schr\"odinger equation is analyzed
analytically. We apply variational modified approach based on the lagrangian
that describe the dynamic of system and with a trial function we obtain a
solution which is more accuracy when compared with a pertubative solution. As a
result, the problem of pulse propagation in a fiber with loss can be described
in good agreement with exact results.

</DOC>
<DOC>
<DOCNO> 101942 </DOCNO>
On the existence of nontrivial solutions for a nonlinear equation


  We prove the existence of a non-trivial solution for a nonlinear equation
related to a measure-valued Lagrangian. The result is based on a compact
embedding theorem of the Lagrangian domain and on the application of the
Mountain Pass Theorem joined to a Palais-Smale condition.

</DOC>
<DOC>
<DOCNO> 152357 </DOCNO>
Cosmology and Modulus Stabilization in the Randall-Sundrum Setup with


  We provide the exact time-dependent cosmological solutions in the
Randall-Sundrum (RS) setup with bulk matter, which may be smoothly connected to
the static RS metric. In the static limit of the extra dimension, the solutions
are reduced to the standard Friedmann equations. In view of our solutions, we
also propose an explanation for how the extra dimension is stabilized in spite
of a flat modulus potential at the classical level.

</DOC>
<DOC>
<DOCNO> 102690 </DOCNO>
Rigorous Real-Time Feynman Path Integral for Vector Potentials


  we will show the existence and uniqueness of a real-time, time-sliced Feynman
path integral for quantum systems with vector potential. Our formulation of the
path integral will be derived on the $L^2$ transition probability amplitude via
improper Riemann integrals. Our formulation will hold for vector potential
Hamiltonian for which its potential and vector potential each carries at most a
finite number of singularities and discontinuities.

</DOC>
<DOC>
<DOCNO> 150661 </DOCNO>
A uniform model of the massive spinning particle in any dimension


  The general model of an arbitrary spin massive particle in any dimensional
space-time is derived on the basis of Kirillov - Kostant - Souriau approach. It
is shown that the model allows consistent coupling to an arbitrary background
of electromagnetic and gravitational fields.

</DOC>
<DOC>
<DOCNO> 39660 </DOCNO>
Possible Studies of Parton Distributions at JHF: polarized pd Drell-Yan


  We discuss possible studies of parton distributions at the proposed 50-GeV PS
facility. First, comments are given in general on the importance of large-x
physics for finding new physics. Second, polarized deuteron reactions are
discussed in connection with new structure functions which are specific for a
spin-1 hadron. Third, if the polarized proton-deuteron Drell-Yan process is
studied at the facility, it could provide information on the light-antiquark
flavor asymmetry in the polarized distributions.

</DOC>
<DOC>
<DOCNO> 118183 </DOCNO>
The NASA Astrophysics Data System: Data Holdings


  Since its inception in 1993, the ADS Abstract Service has become an
indispensable research tool for astronomers and astrophysicists worldwide. In
those seven years, much effort has been directed toward improving both the
quantity and the quality of references in the database. From the original
database of approximately 160,000 astronomy abstracts, our dataset has grown
almost tenfold to approximately 1.5 million references covering astronomy,
astrophysics, planetary sciences, physics, optics, and engineering. We collect
and standardize data from approximately 200 journals and present the resulting
information in a uniform, coherent manner. With the cooperation of journal
publishers worldwide, we have been able to place scans of full journal articles
on-line back to the first volumes of many astronomical journals, and we are
able to link to current version of articles, abstracts, and datasets for
essentially all of the current astronomy literature. The trend toward
electronic publishing in the field, the use of electronic submission of
abstracts for journal articles and conference proceedings, and the increasingly
prominent use of the World Wide Web to disseminate information have enabled the
ADS to build a database unparalleled in other disciplines.
  The ADS can be accessed at http://adswww.harvard.edu

</DOC>
<DOC>
<DOCNO> 85556 </DOCNO>
On the derivation of the equation of motion in a scalar model


  A new method for derivation of the equation of motion from the field equation
is proposed. The problem of embedding the singularities in a field satisfying
the field equations is discussed.

</DOC>
<DOC>
<DOCNO> 121048 </DOCNO>
A new era of spectroscopy: SINFONI, NIR integral field spectroscopy at


  SINFONI, the SINgle Faint Object Near-infrared Investigation, is an
instrument for the Very Large Telescope (VLT), which will start its operation
mid 2002 and allow for the first time near infrared (NIR) integral field
spectroscopy at the diffraction limit of an 8-m telescope. SINFONI is the
combination of two state-of-the art instruments, the integral field
spectrometer SPIFFI, built by the Max-Planck-Institut fuer extraterrestrische
Physik (MPE), and the adaptive optics (AO) system MACAO, built by the European
Southern Observatory (ESO). It will allow a unique type of observations by
delivering simultaneously high spatial resolution (pixel sizes 0.025arcsec to
0.25arcsec) and a moderate spectral resolution (R~2000 to R~4500), where the
higher spectral resolution mode will allow for software OH suppression. This
opens new prospects for astronomy.

</DOC>
<DOC>
<DOCNO> 151270 </DOCNO>
Description of Intersecting Branes via Tachyon Condensation


  We construct a model describing BPS brane-systems using low energy effective
theory of brane-antibrane system. Both parallel branes and intersecting branes
can be treated by this model. After tachyon condensation, the dynamics of
fluctuations around such brane-systems is supersymmetric if the degrees of
freedom are restricted on the branes. The form of the tachyon potential and the
application of this model to the black hole physics are discussed.

</DOC>
<DOC>
<DOCNO> 80758 </DOCNO>
Chiral fermions on the lattice and index relations


  Comparing recent lattice results on chiral fermions and old continuum results
for the index puzzling questions arise. To clarify this issue we start with a
critical reconsideration of the results on finite lattices. We then work out
various aspects of the continuum limit. After determining bounds and norm
convergences we obtain the limit of the anomaly term. Collecting our results
the index relation of the quantized theory gets established. We then compare in
detail with the Atiyah-Singer theorem. Finally we analyze conventional
continuum approaches.

</DOC>
<DOC>
<DOCNO> 84766 </DOCNO>
Horizon Instability in the Cross Polarized Bell-Szekeres Spacetime


  The quasiregular singularities (horizons) that form in the collision of cross
polarized electromagnetic waves are, as in the linear polarized case unstable.
The validity of the Helliwell-Konkowski stability conjecture is tested for a
number of exact back-reaction cases. In the test electromagnetic case the
conjecture fails to predict the correct nature of the singularity while in the
scalar field and in the null dust cases the aggrement is justified.

</DOC>
<DOC>
<DOCNO> 121118 </DOCNO>
A cannonball model of gamma-ray bursts: superluminal signatures


  Recent observations suggest that the long-duration gamma ray bursts (GRBs)
and their afterglows are produced by highly relativistic jets emitted in
supernova explosions. We propose that the result of the event is not just a
compact object plus the ejecta: within a day, a fraction of the parent star
falls back to produce a thick accretion disk. The subsequent accretion
generates jets and constitutes the GRB ``engine'', as in the observed ejection
of relativistic ``cannonballs'' of plasma by microquasars and active galactic
nuclei. The GRB is produced as the jetted cannonballs exit the supernova shell
reheated by the collision, re-emitting their own radiation and boosting the
light of the shell. They decelerate by sweeping up interstellar matter, which
is accelerated to cosmic-ray energies and emits synchrotron radiation: the
afterglow. We emphasize here a smoking-gun signature of this model of GRBs: the
superluminal motion of the afterglow, that can be searched for ---the sooner
the better--- in the particular case of GRB 980425.

</DOC>
<DOC>
<DOCNO> 121291 </DOCNO>
Gamma-Ray Bursts from Up-Scattered Self-Absorbed Synchrotron Emission


  We calculate the synchrotron self-Compton emission from internal shocks
occurring in relativistic winds as a source of gamma-ray bursts, with allowance
for self-absorption. For plausible model parameters most pulses within a
Gamma-Ray Burst (GRB) are optically thick to synchrotron self-absorption at the
frequency at which most electrons radiate. Up-scattering of photon number
spectra harder than $\nu^0$ (such as the self-absorbed emission) yields inverse
Compton photon number spectra that are flat, therefore our model has the
potential of explaining the low-energy indices harder than $\nu^{-2/3}$ (the
optically thin synchrotron limit) that have been observed in some bursts. The
optical counterparts of the model bursts are sufficiently bright to be detected
by such experiments as LOTIS, unless the magnetic field is well below
equipartition.

</DOC>
<DOC>
<DOCNO> 8069 </DOCNO>
Correlation Effects in a One-Dimensional Quarter-Filled Electron System


  A one-dimensional electron system at quarter-filling has been examined by
applying the renormalization group method to a bosonized model with on-site (U)
and nearest-neighbor (V) repulsive interactions. By evaluating both normal
scattering and Umklapp scattering perturbatively, we obtain a phase diagram in
which a metallic state with a 2k_F spin density wave (k_F is the Fermi wave
number) moves into an insulating state with charge disproportionation of a 4k_F
charge density wave with an increase in both U and V. The effect of the
next-nearest-neighbor repulsion is also discussed.

</DOC>
<DOC>
<DOCNO> 70141 </DOCNO>
The 't Hooft interaction at finite T and $\mu$: Beyond the mean field


  We use the N-quantum approach (NQA) to quantum field theory to construct a
solution of the two flavor effective instanton induced `t Hooft interaction
model valid for any temperature (T) and chemical potential ($\mu$) beyond the
mean field theory. The model contains only the $\bar{q}q$ channels. In
constructing this solution we calculate the masses, widths and coupling
constants of bound $\sigma$ and resonant color $\bar{3}$ scalar diquark states.
We find that the chemical potential induced by the interaction cancel exactly
for all values of T in contrast to the Nambu-Jona-Lasinio model. Our method can
also be extended to include the qq channels in the model Lagrangian and we
discuss how the NQA can be used to study the properties of bound diquark states
at finite T and $\mu$.

</DOC>
<DOC>
<DOCNO> 84729 </DOCNO>
Vacuum Energy Density Fluctuations in Minkowski and Casimir States via


  We present calculations of the variance of fluctuations and of the mean of
the energy momentum tensor of a massless scalar field for the Minkowski and
Casimir vacua as a function of an intrinsic scale defined by a smeared field or
by point separation. We point out that contrary to prior claims, the ratio of
variance to mean-squared being of the order unity is not necessarily a good
criterion for measuring the invalidity of semiclassical gravity. For the
Casimir topology we obtain expressions for the variance to mean-squared ratio
as a function of the intrinsic scale (defined by a smeared field) compared to
the extrinsic scale (defined by the separation of the plates, or the
periodicity of space). Our results make it possible to identify the spatial
extent where negative energy density prevails which could be useful for
studying quantum field effects in worm holes and baby universe, and for
examining the design feasibility of real-life `time-machines'.
 For the Minkowski vacuum we find that the ratio of the variance to the
mean-squared, calculated from the coincidence limit, is identical to the value
of the Casimir case at the same limit for spatial point separation while
identical to the value of a hot flat space result with a temporal
point-separation. We analyze the origin of divergences in the fluctuations of
the energy density and discuss choices in formulating a procedure for their
removal, thus raising new questions into the uniqueness and even the very
meaning of regularization of the energy momentum tensor for quantum fields in
curved or even flat spacetimes when spacetime is viewed as having an extended
structure.

</DOC>
<DOC>
<DOCNO> 13784 </DOCNO>
Phase Separation and the Low-Field Bulk Magnetic Properties of


  We present a detailed magnetic study of the perovskite manganite
Pr0.7Ca0.3MnO3 at low temperatures including magnetization and a.c.
susceptibility measurements. The data appear to exclude a conventional spin
glass phase at low fields, suggesting instead the presence of correlated
ferromagnetic clusters embedded in a charge-ordered matrix. We examine the
growth of the ferromagnetic clusters with increasing magnetic field as they
expand to occupy almost the entire sample at H ~ 0.5 T. Since this is well
below the field required to induce a metallic state, our results point to the
existence of a field-induced ferromagnetic insulating state in this material.

</DOC>
<DOC>
<DOCNO> 12578 </DOCNO>
Numerical study of multilayer adsorption on fractal surfaces


  We report a numerical study of van der Waals adsoprtion and capillary
condensation effects on self-similar fractal surfaces. An assembly of uncoupled
spherical pores with a power-law distributin of radii is used to model fractal
surfaces with adjustable dimensions. We find that the commonly used fractal
Frankel-Halsey-Hill equation systematically fails to give the correct dimension
due to crossover effects, consistent with the findings of recent experiments.
The effects of pore coupling and curvature dependent surface tension were also
studied.

</DOC>
<DOC>
<DOCNO> 118810 </DOCNO>
Inflation models, spectral index and observational constraints


  We have evaluated the observational constraints on the spectral index $n$, in
the context of a $\Lambda$CDM model. For $n$ scale-independent, as predicted by
most models of inflation, present data require $n\simeq 1.0 \pm 0.1$ at the
2-$\sigma$ level. We have also studied the two-parameter scale-dependent
spectral index, predicted by running-mass inflation models. Present data allow
significant variation of $n$ in this case, within the theoretically preferred
region of parameter space.

</DOC>
<DOC>
<DOCNO> 169957 </DOCNO>
Contextuality of Approximate Measurements


  The claim of Meyer, Kent and Clifton (MKC) that finite precision measurement
nullifies the Kochen-Specker theorem is criticised. It is argued that, although
MKC have nullified the Kochen-Specker theorem strictly so-called, there are
other, related propositions which are not nullified. The argument given is an
elaboration of some of Mermin's critical remarks. Although MKC allow for the
fact that the observables to be measured cannot be precisely specified, they
continue to assume that the observables which are actually measured are
strictly commuting. As Mermin points out, this assumption is unjustified.
Consequently, the analysis of MKC is incomplete. To make it complete one needs
to investigate the predictions their models make regarding approximate joint
measurements of non-commuting observables. Such an investigation is carried
out, using methods previously developed in connection with approximate joint
measurements of position and momentum. It is shown that a form of contextuality
then re-emerges.

</DOC>
<DOC>
<DOCNO> 170029 </DOCNO>
Quantum Statistics of Hydrogen in Strong Magnetic Fields


  By an extension of the Feynman-Kleinert variational approach, we calculate
the temperature-dependent effective classical potential governing the quantum
statistical properties of a hydrogen atom in a uniform magnetic field. In the
zero-temperature limit, we obtain ground state energies which are accurate for
all magnetic field strengths from weak to strong fields.

</DOC>
<DOC>
<DOCNO> 8327 </DOCNO>
Completely Positive Quantum Dissipation


  A completely positive master equation describing quantum dissipation for a
Brownian particle is derived starting from microphysical collisions, exploiting
a recently introduced approach to subdynamics of a macrosystem. The obtained
equation can be cast into Lindblad form with a single generator for each
Cartesian direction. Temperature dependent friction and diffusion coefficients
for both position and momentum are expressed in terms of the collision
cross-section.

</DOC>
<DOC>
<DOCNO> 72294 </DOCNO>
Large Extra Dimensions and Cosmological Problems


  We consider a variant of the brane-world model in which the universe is the
direct product of a Friedmann, Robertson-Walker (FRW) space and a compact
hyperbolic manifold of dimension $d\geq2$. Cosmology in this space is
particularly interesting. The dynamical evolution of the space-time leads to
the injection of a large entropy into the observable (FRW) universe. The
exponential dependence of surface area on distance in hyperbolic geometry makes
this initial entropy very large, even if the CHM has relatively small diameter
(in fundamental units). This provides an attractive reformulation of the
cosmological entropy problem, in which the large entropy is a consequence of
the topology, though we would argue that a final solution of the entropy
problem requires a dynamical explanation of the topology of spacetime.
Nevertheless, it is reassuring that this entropy can be achieved within the
holographic limit if the ordinary FRW space is also a compact hyperbolic
manifold. In addition, the very large statistical averaging inherent in the
collapse of the initial entropy onto the brane acts to smooth out initial
inhomogeneities. This smoothing is then sufficient to account for the current
homogeneity of the universe. With only mild fine-tuning, the current flatness
of the universe can also then be understood. Finally, recent brane-world
approaches to the hierarchy problem can be readily realized within this
framework.

</DOC>
<DOC>
<DOCNO> 11601 </DOCNO>
Giant enhancement of the thermal Hall conductivity \kappa_{xy} in the


  In high-purity crystals of YBa_2Cu_3O_7, the quasiparticle (qp) lifetime
  \tau and the (weak-field) thermal Hall conductivity \kappa_{xy} undergo
dramatic increases below 90K. We present a detailed picture of the behavior of
\kappa_{xy} at low temperature, in particular its scaling properties, which are
directly relevant to the issue of whether Landau quantization of the qp states
occurs.

</DOC>
<DOC>
<DOCNO> 102419 </DOCNO>
On nonperturbative localization with quasi-periodic potential


  The two main results of the article are concerned with Anderson Localization
for one-dimensional lattice Schroedinger operators with quasi-periodic
potentials with d frequencies. First, in the case d = 1 or 2, it is proved
that the spectrum is pure-point with exponentially decaying eigenfunctions for
all potentials (defined in terms of a trigonometric polynomial on the
d-dimensional torus) for which the Lyapounov exponents are strictly positive
for all frequencies and all energies. Second, for every non-constant
real-analytic potential and with a Diophantine set of d frequencies, a lower
bound is given for the Lyapounov exponents for the same potential rescaled by
a sufficiently large constant.

</DOC>
<DOC>
<DOCNO> 101454 </DOCNO>
D-brane charge, flux quantisation and relative (co)homology


  We reconsider the problem of U(1) flux and D0-charge for D-branes in the WZW
model and investigate the relationship between the different definitions that
have been proposed recently. We identify the D0-charge as a particular
reduction of a class in the relative cohomology of the group modulo the
D-submanifold. We investigate under which conditions this class is equivalent
to the first Chern class of a line bundle on the D-submanifold and we find that
in general there is an obstruction given by the cohomology class of the NS
3-form. Therefore we conclude that for topologically nontrivial B-fields, there
is strictly speaking no U(1) gauge field on the D-submanifold. Nevertheless the
ambiguity in the flux is not detected by the D0-charge. This has a natural
interpretation in terms of gerbes.

</DOC>
<DOC>
<DOCNO> 14156 </DOCNO>
Phase transitions in autonomous reaction-diffusion systems on a


  The family of autonomous reaction-diffusion models on a one-dimensional
lattice with boundaries is studied. By autonomous, it is meant that the
evolution equation for n-point functions contain only n- or less- point
functions. It is shown that these models exhibit a static and a dynamic phase
transition.

</DOC>
<DOC>
<DOCNO> 169665 </DOCNO>
Discrete Phase Measurements and the Bell inequality


  We present a formulation of the Bell inequalities using simple correlated
photon number states and phase measurements. Such tests generally require
binning of the information, and this effect is closely examined. Our proposal
opens up the opportunity for a new novel test of quantum mechanics versus local
realism. Some insight in entanglement in such systems may be achieved.

</DOC>
<DOC>
<DOCNO> 13964 </DOCNO>
Velocity-force characteristics of a driven interface in a disordered


  Using a dynamic functional renormalization group treatment of driven elastic
interfaces in a disordered medium, we investigate several aspects of the
creep-type motion induced by external forces below the depinning threshold
$f_c$: i) We show that in the experimentally important regime of forces
slightly below $f_c$ the velocity obeys an Arrhenius-type law
$v\sim\exp[-U(f)/T]$ with an effective energy barrier $U(f)\propto (f_{c}-f)$
vanishing linearly when f approaches the threshold $f_c$. ii) Thermal
fluctuations soften the pinning landscape at high temperatures. Determining the
corresponding velocity-force characteristics at low driving forces for internal
dimensions d=1,2 (strings and interfaces) we find a particular non-Arrhenius
type creep $v\sim \exp[-(f_c(T)/f)^{\mu}]$ involving the reduced threshold
force $f_c(T)$ alone. For d=3 we obtain a similar v-f characteristic which is,
however, non-universal and depends explicitly on the microscopic cutoff.

</DOC>
<DOC>
<DOCNO> 119372 </DOCNO>
A New Narrow-Line Seyfert 1 galaxy : RXJ1236.9+2656


  We report identification of a narrow-line Seyfert 1 galaxy RXJ1236.9+2656.
X-ray emission from the NLS1 galaxy undergoes long-term variability with
0.1--2.0 keV flux changing by a factor of 2 within about 3 yr. The ROSAT PSPC
spectrum of RXJ1236.9+2656 is well represented by a power-law of Gamma = 3.7
absorbed by matter in our own Galaxy (N_H = 1.33X10^20 cm**-2). Intrinsic soft
X-ray luminosity of the NLS1 galaxy is estimated to be 1.5X10^43 erg/s in the
energy band of 0.1-2.0 keV. The optical spectrum of RXJ1236.9+2656 is typical
of NLS1 galaxies and shows narrow Balmer emission lines (1100 km/s < FWHM <
1700 km/s) of Hbeta, Halpha, and forbidden lines of [O III] and [N II]. Fe II
multiplets, usually present in optical spectra of NLS1 galaxies, are also
detected in RXJ1236.9+2656.

</DOC>
<DOC>
<DOCNO> 120755 </DOCNO>
Halo streams as relicts from the formation of the Milky Way


  In this contribution we discuss the expected properties of our halo if our
Galaxy had been built from mergers of smaller systems. Using both analytic
arguments and high-resolution simulations, we find that the Galactic halo in
the Solar neighbourhood should have a smooth spatial distribution and that its
stellar velocity ellipsoid should consist of several hundred kinematically cold
streams, relicts from the different merging events. We also discuss
observational evidence which supports this hierarchical picture: two stellar
streams originating in the same system that probably fell onto the Milky Way
about ten Gyr ago. Finally we address what future astrometric missions like
FAME or GAIA may reveal by observing the motions of nearby halo stars.

</DOC>
<DOC>
<DOCNO> 84430 </DOCNO>
Solutions to Cosmological Problems with Energy Conservation and Varying


  The flatness and cosmological constant problems are solved with varying speed
of light c, gravitational coupling strength G and cosmological parameter
Lambda, by explicitly assuming energy conservation of observed matter. The
present solution to the flatness problem is the same as the previous solution
in which energy conservation was absent.

</DOC>
<DOC>
<DOCNO> 70613 </DOCNO>
Analytical construction of a nonperturbative vacuum for the open bosonic


  Using analytical methods, a nonpertubative vacuum is constructed recursively
in the field theory for the open bosonic string. Evidence suggests it
corresponds to the Lorentz-invariant endpoint of tachyon condensation on a
D25-brane. The corresponding string field is a twisted squeezed state.

</DOC>
<DOC>
<DOCNO> 101732 </DOCNO>
Localizations of Groups


  A group homomorphism eta:A-> H is called a localization of A if every
homomorphism phi:A-> H can be `extended uniquely' to a homomorphism Phi:H-> H
in the sense that Phi eta = phi. This categorical concepts, obviously not
depending on the notion of groups, extends classical localizations as known for
rings and modules. Moreover this setting has interesting applications in
homotopy theory. For localizations eta:A-> H of (almost) commutative structures
A often H resembles properties of A, e.g. size or satisfying certain systems of
equalities and non-equalities. Perhaps the best known example is that
localizations of finite abelian groups are finite abelian groups. This is no
longer the case if A is a finite (non-abelian) group. Libman showed that A_n->
SO_{n-1}(R) for a natural embedding of the alternating group A_n is a
localization if n even and n >= 10 . Answering an immediate question by Dror
Farjoun and assuming the generalized continuum hypothesis GCH we recently
showed in math.LO/9912191 that any non-abelian finite simple has arbitrarily
large localizations. In this paper we want to remove GCH so that the result
becomes valid in ordinary set theory. At the same time we want to generalize
the statement for a larger class of A 's.

</DOC>
<DOC>
<DOCNO> 68272 </DOCNO>
An updated analysis of eps'/eps in the standard model with hadronic


  We discuss the theoretical and experimental status of the CP violating ratio
eps'/eps. We revise our 1997 standard-model estimate-based on hadronic matrix
elements computed in the chiral quark model up to O(p^4) in the chiral
expansion-by including an improved statistical analysis of the uncertainties
and updated determination of the Cabibbo-Kobayashi-Maskawa elements and other
short-distance parameters. Using normal distributions for the experimental
input data we find Re eps'/eps = (2.2 \pm 0.8) x 10^{-3}, whereas a flat
scanning gives 0.9 x 10^{-3} < Re eps'/eps < 4.8 x 10^{-3}. Both results are in
agreement with the current experimental data. The key element in our estimate
is, as before, the fit of the Delta I=1/2 rule, which allows us to absorb most
of the theoretical uncertainties in the determination of the model-dependent
parameters in the hadronic matrix elements. Our semi-phenomenological approach
leads to numerical stability against variations of the renormalization scale
and scheme dependence of the short- and long-distance components. The same
dynamical mechanism at work in the selection rule also explains the larger
value obtained for \ratio with respect to other estimates. A coherent picture
of K -> pi pi decays is thus provided.

</DOC>
<DOC>
<DOCNO> 80693 </DOCNO>
K0-K0bar Mixing with Wilson Fermions without Subtractions


  By using suitable Ward identities, we show that it is possible to compute
K0-K0bar mixing without subtracting the terms generated by explicit chiral
symmetry breaking present in Wilson-like lattice actions. The accuracy in the
determination of the amplitudes is of O(a), which is the best one attainable in
the absence of improvement.

</DOC>
<DOC>
<DOCNO> 178780 </DOCNO>
External Coulomb and angular momentum influence on isotope composition


  The Markov chain statistical multifragmentation model predicts inhomogeneous
distributions of fragments and their isospin in the freeze-out volume caused by
an angular momentum and external long-range Coulomb field. These effects can
take place in peripheral nucleus-nucleus collisions at intermediate energies
and lead to neutron-rich isotopes produced in the midrapidity kinematical
region of the reactions.

</DOC>
<DOC>
<DOCNO> 84582 </DOCNO>
Equivalent frames in Brans-Dicke theory


  We discuss the physical equivalence between the Einstein and Jordan frames in
Brans-Dicke theory. The inequivalence of conformal transformed theories is
clarified with the help of an old equivalence theorem of Chrisholm's.

</DOC>
<DOC>
<DOCNO> 102443 </DOCNO>
UHF flows and the flip automorphism


  A UHF flow is an infinite tensor product type action of the reals on a UHF
algebra $A$ and the flip automorphism is an automorphism of $A\otimes A$
sending $x\otimes y$ into $y\otimes x$. If $\alpha$ is an inner perturbation of
a UHF flow on $A$, there is a sequence $(u_n)$ of unitaries in $A\otimes A$
such that $\alpha_t\otimes \alpha_t(u_n)-u_n$ converges to zero and the flip is
the limit of $\Ad u_n$. We consider here whether the converse holds or not and
solve it with an additional assumption: If $A\otimes A\cong A$ and $\alpha$
absorbs any UHF flow $\beta$ (i.e., $\alpha\otimes\beta$ is cocycle conjugate
to $\alpha$), then the converse holds; in this case $\alpha$ is what we call a
universal UHF flow.

</DOC>
<DOC>
<DOCNO> 99935 </DOCNO>
Invariant Measures on Polarized Submanifolds in Group Quantization


  We provide an explicit construction of quasi-invariant measures on polarized
coadjoint orbits of a Lie group G. The use of specific (trivial) central
extensions of G by the multiplicative group ${R}^+$ allows us to restore the
strict invariance of the measures and, accordingly, the unitarity of the
quantization of coadjoint orbits. As an example, the representations of
$SL(2,\Real)$ are recovered.

</DOC>
<DOC>
<DOCNO> 85529 </DOCNO>
Deviation equations of Synge and Schild over spaces with affine


  Deviation equation of Synge and Schild has been investigated over spaces with
affine connections and metrics. It is shown that the condition for the
vanishing of the Lie derivative of a vector field along a given non-null
(non-isotropic) vector field u for obtaining this equation is only a sufficient
(but not necessary) condition. By means of the vector field u and the
projective metric (orthogonal to it) projected deviation equations of Synge and
Schild have been obtained for a vector field, orthogonal to the given vector
field u, as well as for the square of its length. For a given non-isotropic,
auto-parallel and normalized vector field u this equation could have some
simple solutions.
  PACS numbers: 02.90; 04.50+h; 04.90.+e: 04.30.+x

</DOC>
<DOC>
<DOCNO> 119584 </DOCNO>
Particle acceleration at ultrarelativistic shocks: an eigenfunction


  We extend the eigenfunction method of computing the power-law spectrum of
particles accelerated at a relativistic shock fronts to apply to shocks of
arbitrarily high Lorentz factor. In agreement with the findings of Monte-Carlo
simulations, we find the index of the power-law distribution of accelerated
particles which undergo isotropic diffusion in angle at an ultrarelativistic,
unmagnetized shock is s=4.23 (where s=-d(ln f)/dp with f the Lorentz invariant
phase-space density and p the momentum). This corresponds to a synchrotron
index for uncooled electrons of a=0.62 (taking cooling into account a=1.12),
where a=-d(ln F)/dn, F is the radiation flux and n the frequency. We also
present an approximate analytic expression for the angular distribution of
accelerated particles, which displays the effect of particle trapping by the
shock: compared with the non-relativistic case the angular distribution is
weighted more towards the plane of the shock and away from its normal. We
investigate the sensitivity of our results to the transport properties of the
particles and the presence of a magnetic field. Shocks in which the ratio of
Poynting to kinetic energy flux upstream is not small are less compressive and
lead to larger values of $s$.

</DOC>
<DOC>
<DOCNO> 119592 </DOCNO>
IR-TF Relation In The Zone Of Avoidance With 2MASS


  Using the Tully-Fisher relation, one can map the peculiar velocity field and
estimate the mass in regions such as the Great Attractor. 2MASS is surveying
the full sky in J, H and K bands and has the great advantage that it allows us
to detect galaxies more uniformly to lower Galactic latitude than optical
surveys. This study shows the feasibility of using 2MASS and the TF relation to
probe large scale structure. We found that (i) we can use axis ratio $b/a$ up
to 0.5; (ii) intrinsic extinction is present (up to 0.5mag at J, 0.1 mag at K);
(iii) the zero-point of the TF relation is independent of the 2MASS magnitude
measurement and is consistent with the HST Key-Project value; (iv) the 2MASS
K-band 20th mag/arcsec$^2$ isophotal aperture magnitude produces the best TF
relation; and (v) there is no type dependence of the residuals

</DOC>
<DOC>
<DOCNO> 123306 </DOCNO>
Ages and Metallicities of Fornax Dwarf Ellipticals


  Narrow band photometry is presented on 27 dwarf ellipticals in the Fornax
cluster. Calibrated with Galactic globular cluster data and spectrophotometric
population models, the colors indicated that dwarf ellipticals have a mean
[Fe/H] of -1.00+/-0.28 ranging from -1.6 to -0.4. The mean age of dwarf
ellipticals, also determined photometrically, is estimated at 10+/-1 Gyrs
compared to 13 Gyrs for bright Fornax ellipticals. Comparison of our
metallicity color and Mg_2 indices demonstrates that the [Mg/Fe] ratio is lower
in dwarf ellipticals than their more massive cousins, which is consistent with
a longer duration of initial star formation to explain their younger ages.
There is a increase in dwarf metallicity with distance from the Fornax cluster
center where core galaxies are, on average, 0.5 dex more metal-poor than halo
dwarfs. In addition, we find the halo dwarfs are younger in mean age compared
to core dwarfs. One possible explanation is that the intracluster medium ram
pressure strips the gas from dwarf ellipticals halting star formation (old age)
and stopping enrichment (low metallicity) as they enter the core.

</DOC>
<DOC>
<DOCNO> 10091 </DOCNO>
Disordered Quantum Solids


  Due to the peculiar non-fermi liquid of one dimensional systems, disorder has
particularly strong effects. We show that such systems belong to the more
general class of disordered quantum solids. We discuss the physics of such
disordered interacting systems and the methods that allows to treat them. In
addition to, by now standard renormalization group methods, We explain how a
simple variational approach allows to treat these problems even in case when
the RG fails. We discuss various physical realizations of such disordered
quantum solids both in one and higher dimensions (Wigner crystal, Bose glass).
We investigate in details the interesting example of a disordered Mott
insulator and argue that intermediate disorder can lead to a novel phase, the
Mott glass, intermediate between a Mott and and Anderson insulator.

</DOC>
<DOC>
<DOCNO> 170459 </DOCNO>
Maximum-likelihood reconstruction of CP maps


  We present a method for the determination of the completely positive (CP) map
describing a physical device based on random preparation of the input states,
random measurements at the output, and maximum-likelihood principle. In the
numerical implementation the constraint of completely positivity can be imposed
by exploiting the isomorphism between linear transformations from Hilbert
spaces $\cal H$ to $\cal K$ and linear operators in ${\cal K}\otimes {\cal H}$.
The effectiveness of the method is shown on the basis of some examples of
reconstruction of CP maps related to quantum communication channels for qubits.

</DOC>
<DOC>
<DOCNO> 152450 </DOCNO>
On the supersymmetric non-abelian Born-Infeld action


  We review an iterative construction of the supersymmetric non-abelian
Born-Infeld action. We obtain the action through second order in the
fieldstrength. Kappa-invariance fixes the ordenings which turn out to deviate
from the symmetrized trace proposal.

</DOC>
<DOC>
<DOCNO> 85163 </DOCNO>
Dyonic Wormholes in 5D Kaluza-Klein Theory


  New spherically symmetric dyonic solutions, describing a wormhole-like class
of spacetime configurations in five-dimensional Kaluza-Klein theory, are given
in an explicit form. For this type of solution the electric and magnetic fields
cause a significantly different global structure. For the electric dominated
case, the solution is everywhere regular but, when the magnetic strength
overcomes the electric contribution, the mouths of the wormhole become singular
points. When the electric and magnetic charge parameters are identical, the
throats ``degenerate'' and the solution reduces to the trivial embedding of the
four-dimensional massless Reissner-Nordstr{\"o}m black hole solution. In
addition, their counterparts in eleven-dimensional supergravity are constructed
by a non-trivial uplifting.

</DOC>
<DOC>
<DOCNO> 85151 </DOCNO>
Black Holes and Naked Singularities in Low Energy Limit of String


  We show that the black hole solutions of the effective string theory action,
where one-loop effects that couple the moduli to gravity via a Gauss-Bonnet
term are taken into account, admit primary scalar hair. The requirement of
absence of naked singularities imposes an upper bound on the scalar charges.

</DOC>
<DOC>
<DOCNO> 117964 </DOCNO>
Cosmic Equation of State, Quintessence and Decaying Dark Matter


  If CDM particles decay and their lifetime is comparable to the age of the
Universe, they can modify its equation of state. By comparing the results of
numerical simulations with high redshift SN-Ia observations we show that this
hypothesis is consistent with present data. Fitting the simplest quintessence
models with constant $w_q$ to data leads to $w_q \lesssim -1$. We show that a
universe with a cosmological constant or quintessence matter with $w_q \sim -1$
and a decaying Dark Matter has an effective $w_q < -1$ and fits SN data better
than stable CDM or quintessence models with $w_q > -1$.

</DOC>
<DOC>
<DOCNO> 116595 </DOCNO>
Axioms for Mach's mechanics


  We present an axiomatic framework for what we call Mach's mechanics, inspired
on the ideas by A. K. T. Assis and P. Graneau about relational mechanics. We
show that contrarily to what is suggested by these authors, Mach's principle
does not need to be committed with any Weber's like gravitational force.
Actually it is possible to settle an axiomatic framework for non-relativistic
classical particle mechanics which incorporates Mach's principle and is
consistent with any force that obeys the newtonian action-reaction principle.
We make further criticisms concerning relational mechanics.

</DOC>
<DOC>
<DOCNO> 102057 </DOCNO>
Holomorphic vector fields and minimal Lagrangian submanifolds


  The purpose of this note is to establish the following theorem: Let N be a
Kahler manifold, L be a compact oriented immersed minimal Lagrangian
submanifold in N and V be a holomorphic vector field in a neighbourhood of L in
N. Let div(V) be the (complex) divergence of V. Then the integral of div(V)
over L is 0. Vice versa let N^2n be Kahler-Einstein with non-zero scalar
curvature and L^n be a totally real oriented embedded n-dimensional
real-analytic submanifold of N s.t. the divergence of any holomorphic vector
field defined in a neighbourhood of L in N integrates to 0 on L. Then L is a
minimal Lagrangian submanifold of N.

</DOC>
<DOC>
<DOCNO> 101075 </DOCNO>
Implicit integration of the TDGL equations of superconductivity


  This article is concerned with the integration of the time-dependent
Ginzburg--Landau (TDGL) equations of superconductivity. Four algorithms,
ranging from fully explicit to fully implicit, are presented and evaluated for
stability, accuracy, and compute time. The benchmark problem for the evaluation
is the equilibration of a vortex configuration in a superconductor that is
embedded in a thin insulator and subject to an applied magnetic field.

</DOC>
<DOC>
<DOCNO> 178601 </DOCNO>
Algebraic Model for scattering in three-s-cluster systems. I.


  A framework to calculate two-particle matrix elements for fully
antisymmetrized three-cluster configurations is presented. The theory is
developed for a scattering situation described in terms of the Algebraic Model.
This means that the nuclear many-particle state and its asymptotic behaviour
are expanded in terms of oscillator states of the intra-cluster coordinates.
The Generating Function technique is used to optimize the calculation of matrix
elements. In order to derive the dynamical equations, a multichannel version of
the Algebraic Model is presented.

</DOC>
<DOC>
<DOCNO> 178517 </DOCNO>
Soliton excitations as emitted clusters on nuclear surfaces


  This work reports on calculations of the deformation energy of a nucleus plus
an emitted cluster as a soliton moving on its surface. The potential barrier
against the emission of a soliton is calculated within the
macroscopic-microscopic method. The outer turning point of the barrier
determines limitations on the geometrical and kinematical parameters for the
formation of a surface soliton. For large asymmetry, the two-center shell model
is used to assign a structure to the soliton. Calculations for
$^{248}$N\lowercase{o} with the emission of a $^{40}$C\lowercase{a} soliton are
reported; likewise for $^{224}$T\lowercase{h} with the emission of $^{16}$O.
Except for necked shapes at the very first stages of soliton formation, the
greatest portion of the deformation path displays rather compact configurations
with large neck radii. These shape sequences correspond to allowable soliton
velocities. Close to and just beyond the touching point configuration, where
the shape becomes concave, the width and the velocity of the soliton approach
zero. The calculations suggest that the emission of a $^{40}$C\lowercase{a}
structure is quite probable due to a low potential barrier, whereas the
emission of an $^{16}$O type soliton is rather unlikely due to the higher
penetration barrier.

</DOC>
<DOC>
<DOCNO> 150727 </DOCNO>
Dynamics of Multiparticle Systems with non - Abelian Symmetry


  We consider the dynamics governing the evolution of a many body system
constrained by an nonabelian local symmetry. We obtain explicit forms of the
global macroscopic condition assuring that at the microscopic level the
evolution respects the overall symmetry constraint. We demonstrate the
constraint mechanisms for the case of SU(2) system comprising particles in
fundamental, and adjoint representations (`nucleons' and `pions').

</DOC>
<DOC>
<DOCNO> 7870 </DOCNO>
Instantaneous Normal Mode analysis of liquid HF


  We present an Instantaneous Normal Modes analysis of liquid HF aimed to
clarify the origin of peculiar dynamical properties which are supposed to stem
from the arrangement of molecules in linear hydrogen-bonded network. The
present study shows that this approach is an unique tool for the understanding
of the spectral features revealed in the analysis of both single molecule and
collective quantities. For the system under investigation we demonstrate the
relevance of hydrogen-bonding ``stretching'' and fast librational motion in the
interpretation of these features.

</DOC>
<DOC>
<DOCNO> 150615 </DOCNO>
A consistent electromagnetic duality


  We present a new view for duality in classical electromagnetic theory, based
on the physical properties of a dual theory, eliminating the problems of the
usual treatment of the subject.

</DOC>
<DOC>
<DOCNO> 101708 </DOCNO>
Superatomic Boolean Algebras: maximal rigidity


  We prove that for any superatomic Boolean Algebra of cardinality >beth_omega
there is an automorphism moving uncountably many atoms. Similarly for larger
cardinals. Any of those results are essentially best possible.

</DOC>
<DOC>
<DOCNO> 67932 </DOCNO>
The Nonperturbative Color Meissner Effect in a Two-Flavor Color


  Color superconductivity in QCD breaks the SU(3) color gauge group down to
SU(2), inducing masses in five of the eight gluons. This is a dynamical Higgs
effect, in which the diquark condensate acts as the vacuum expectation value of
a composite scalar field. In order to analyze this effect at low quark density,
when gaps are large and generated nonperturbatively, we use instanton-induced
quark interactions augmented with gauge-invariant interactions between quarks
and perturbative gluons. The five gluon masses are found from the static limit
of the relevant polarization operators, in which transversality is maintained
via the Nambu-Goldstone modes of broken color symmetry. Working in the
microscopic theory we calculate these masses to one-loop order and estimate
their density dependence. Finally, we speculate that the Meissner effect may
postpone the onset of color superconductivity to higher matter density than
estimated previously.

</DOC>
<DOC>
<DOCNO> 122640 </DOCNO>
WIYN Open Cluster Study 5. Lithium Depletion and Metallicity in G and K


  We present an analysis of high quality spectra of members of the young
cluster M35. By using a multi-fiber spectrograph, we are able to collect high
signal-to-noise, high resolution spectra of a sample of photometric candidate
members. Accurate radial velocities are used to establish the membership status
and rotational velocities are measured using cross-correlation. We also derive
the metal content of the cluster, [Fe/H]= -0.21$\pm$0.10, based on spectral
synthesis. Finally, we derive the lithium abundances of the bona fide cluster
members and compare the results with members of other clusters. For example,
M35 shows a smaller range in both rotation rates and lithium abundances as
compared to the Pleiades. We discuss possible roles of various parameters. Our
high quality M35 database of lithium abundances and rotational velocities are
perfectly suited to be used as a laboratory to test theoretical models dealing
with the lithium depletion phenomenon.

</DOC>
<DOC>
<DOCNO> 84526 </DOCNO>
Lorenz Gauge in Quantum Cosmology


  In a path-integral approach to quantum cosmology, the Lorenz gauge-averaging
term is studied for Euclidean Maxwell theory on a portion of flat four-space
bounded by two concentric three-spheres, but with arbitrary values of the gauge
parameter. The resulting set of eigenvalue equations for normal and
longitudinal modes of the electromagnetic potential cannot be decoupled, and is
here studied with a Green-function method. This means that an equivalent
equation for longitudinal modes is obtained which has integro-differential
nature, after inverting a differential operator in the original coupled system.
A complete calculational scheme is therefore obtained for the one-loop
semiclassical evaluation of the wave function of the universe in the presence
of gauge fields. This might also lead to a better understanding of how gauge
independence is actually achieved on manifolds with boundary, whose
consideration cannot be avoided in a quantum theory of the universe.

</DOC>
<DOC>
<DOCNO> 70298 </DOCNO>
The Fractal Geometry of Critical Systems


  We investigate the geometry of a critical system undergoing a second order
thermal phase transition. Using a local description for the dynamics
characterizing the system at the critical point T=Tc, we reveal the formation
of clusters with fractal geometry, where the term cluster is used to describe
regions with a nonvanishing value of the order parameter. We show that,
treating the cluster as an open subsystem of the entire system, new
instanton-like configurations dominate the statistical mechanics of the
cluster. We study the dependence of the resulting fractal dimension on the
embedding dimension and the scaling properties (isothermal critical exponent)
of the system. Taking into account the finite size effects we are able to
calculate the size of the critical cluster in terms of the total size of the
system, the critical temperature and the effective coupling of the long
wavelength interaction at the critical point. We also show that the size of the
cluster has to be identified with the correlation length at criticality.
Finally, within the framework of the mean field approximation, we extend our
local considerations to obtain a global description of the system.

</DOC>
<DOC>
<DOCNO> 150592 </DOCNO>
Anomalies & Tadpoles


  We show that massless RR tadpoles in vacuum configurations with open and
unoriented strings are always related to anomalies. RR tadpoles arising from
sectors of the internal SCFT with non-vanishing Witten index are in one-to-one
correspondence with conventional irreducible anomalies. The anomalous content
of the remaining RR tadpoles can be disclosed by considering anomalous
amplitudes with higher numbers of external legs. We then provide an explicit
parametrization of the anomaly polynomial in terms of the boundary reflection
coefficients, i.e. one-point functions of massless RR fields on the disk. After
factorization of the reducible anomaly, we extract the relevant WZ couplings in
the effective lagrangians.

</DOC>
<DOC>
<DOCNO> 68784 </DOCNO>
Semileptonic inclusive heavy meson decay: duality in a nonrelativistic


  Quark-hadron duality in the inclusive semileptonic decay $B\to X_c l\nu$ in
the Shifman-Voloshin limit $\Lambda \ll \delta m=m_b - m_c \ll m_b, m_c$ is
studied within a nonrelativistic potential model. The integrated semileptonic
decay rate is calculated in two ways: first, by constructing the Operator
Product Expansion, and second by a direct summation of the exclusive channels.
Sum rules (Bjorken, Voloshin, etc.) for the potential model are derived,
providing a possibility to compare the two representations for $\Gamma(B\to X_c
l\nu)$. An explicit difference between them referred to as duality-violation
effect is found. The origin of this effect is related to higher charm
resonances which are kinematically forbidden in the decay process but are
nevertheless picked up by the OPE.
  Within the considered $1/m_c^2$ order the OPE and the sum over exclusive
channels match each other, up to the contributions of higher resonances, by
virtue of the sum rules. In particular this is true for the terms of order
$\delta m^2/m_c^2$ and $\Lambda \delta m/m_c^2$ which are present in each of
the decay channels and cancel in the sum of these channels due to the Bjorken
and Voloshin sum rules, respectively. The size of the duality violation effects
is estimated to be of the order $O(\Lambda^{2+b}/m_c^2\delta m^b)$ with $b>0$
depending on the details of the potential. Constraints for a better accuracy
are discussed.

</DOC>
<DOC>
<DOCNO> 152586 </DOCNO>
Role of Ambiguities and Gauge Invariance in the Calculation of the


  We investigate the possibility of Lorentz and CPT violations in the photon
sector, of the Chern-Simons form, be induced by radiative corrections arising
from the Lorentz and CPT non-invariant fermionic sector of an extended version
of QED. By analyzing the modified vacuum polarization tensor, three
contributions are considered: two of them can be identified with well known
amplitudes; the (identical) QED vacuum polarization tensor and the (closely
related) $AVV$ triangular amplitude. These amplitudes are evaluated in their
most general form (to include in our discussion automatically the question of
ambiguities) on the point of view of a strategy to manipulate and calculate
divergent amplitudes that can avoid the explicit calculation of divergent
integrals. Rather than this only general properties are used in intermediary
steps. With this treatment, the results obtained by others authors can be
easily recovered and we show that, if we choose to impose U(1) gauge invariance
maintenance in the pure QED calculated amplitudes, to be consistent with the
renormalizability, the induced Chern-Simons term assumes a nonvanishing
ambiguities free value. However if, in addition, we choose to get an answer
consistent with renormalizability by anomaly cancellation of the Standard Model
a vanishing value can be obtained, in accordance with what was previously
conjectured by other authors.

</DOC>
<DOC>
<DOCNO> 9335 </DOCNO>
Detection of a Schroedinger's Cat State in an rf-SQUID


  We present experimental evidence for a coherent superposition of
macroscopically distinct flux states in an rf-SQUID. When the external flux
Phi_x applied to the SQUID is near 1/2 of a flux quantum Phi_0, the SQUID has
two nearly degenerate configurations: the zero- and one-fluxoid states,
corresponding to a few microamperes of current flowing clockwise or
counterclockwise, respectively. The system is modeled as a particle in a
double-well potential where each well represents a distinct fluxoid state (0 or
1) and the barrier between the wells can be controlled in situ. For low damping
and a sufficiently high barrier, the system has a set of quantized energy
levels localized in each well. The relative energies of these levels can be
varied with Phi_x. External microwaves are used to pump the system from the
well-localized ground state of one well into one of a pair of excited states
nearer the top of the barrier. We spectroscopically map out the energy of these
levels in the neighborhood of their degeneracy point by varying Phi_x as well
as the barrier height. We find a splitting between the two states at this
point, when both states are below the classical energy barrier, indicating that
the system attains a coherent superposition of flux basis states that are
macroscopically distinct in that their mean fluxes differ by more than 1/4
Phi_0 and their currents differ by several microamperes.

</DOC>
<DOC>
<DOCNO> 13590 </DOCNO>
A Dynamical Thermostat Approach To Financial Asset Price Dynamics


  A dynamical price formation model for financial assets is presented. It aims
to capture the essence of speculative trading where mispricings of assets are
used to make profits. It is shown that together with the incorporation of the
concept of risk aversion of agents the model is able to reproduce several key
characteristics of financial price series. The approach is contrasted to the
conventional view of price formation in financial economics.

</DOC>
<DOC>
<DOCNO> 71911 </DOCNO>
Confining strings in the Abelian-projected SU(3)-gluodynamics II.


  The generalization of 4D confining string theory to the SU(3)-inspired case
is derived. It describes string representation of the Wilson loop in the
SU(3)-analogue of compact QED extended by the $\theta$-term. It is shown that
although the obtained theory of confining strings differs from that of compact
QED, their low-energy limits have the same functional form. This fact leads to
the appearance of the string $\theta$-term in the low-energy limit of the
SU(3)-inspired confining string theory. In particular, it is shown that in the
extreme strong coupling regime, the crumpling of string world sheets could
disappear owing to the string $\theta$-term at $\theta=\pi/12$. Finally, some
characteristic features of the SU(N)-case are pointed out.

</DOC>
<DOC>
<DOCNO> 122287 </DOCNO>
Testing current synthesis models of the X-ray background


  We present synthesis models of the X-ray background where the available X-ray
observational constraints are used to derive information on the AGN population
properties. We show the need for luminous X-ray absorbed AGNs, the QSO2s, in
reproducing the 2-10 keV source counts at relatively bright fluxes. We compare
a model where the evolution of absorbed AGNs is faster than that of unabsorbed
ones, with a standard model where absorbed and unabsorbed AGNs evolve at the
same rate. It is found that an increase by a factor of ~2 from z=0 to z~1.3 in
the ratio between absorbed and unabsorbed AGNs would provide a significant
improvement in the data description. Finally, we make predictions on the AGNs
to be observed in deep X-ray surveys which contain information on the AGN space
density at high redshift.

</DOC>
<DOC>
<DOCNO> 12283 </DOCNO>
Magnetization plateaus and phase diagram in polymerized S=1/2 XXZ chains


  The magnetization plateaus of $p$-merized $S=1/2$ XXZ chains are studied for
general values of $p$. Two plateau-non-plateau critical lines and one
plateau-plateau critical line are found for each value of $p$. The universality
class of the plateau-non-plateau transition belongs to
Brezinskii-Kosterlitz-Thouless (BKT) type and that of the plateau-plateau
transition, to the Gaussian type. The critical points are determined by level
spectroscopic analysis of the numerical diagonalization results for $4 \le p
\le 8$. The multicritical points are calculated using the integral equations
based on the Bethe ansatz solution of the XXZ model. The behavior of
multicritical points are analyzed in detail for large $p$. It is found that the
plateau region is enhanced with the increase of periodicity $p$ although the
non-plateau region persists as far as $p$ is finite.

</DOC>
<DOC>
<DOCNO> 178450 </DOCNO>
Realistic Shell-Model Calculations for Proton-Rich N=50 Isotones


  The structure of the N=50 isotones 98Cd, 97Ag, and 96Pd is studied in terms
of shell model employing a realistic effective interaction derived from the
Bonn-A nucleon-nucleon potential. The single-hole energies are fixed by
resorting to an analysis of the low-energy spectra of the isotones with A>= 91.
Comparison shows that our results are in very satisfactory agreement with the
available experimental data. This supports confidence in the predictions of our
calculations

</DOC>
<DOC>
<DOCNO> 152580 </DOCNO>
Derivative expansion for the effective action of chiral gauge fermions.


  Explicit exact formulas are presented, for the leading order term in a strict
chiral covariant derivative expansion, for the abnormal parity component of the
effective action of two- and four-dimensional Dirac fermions in presence of
scalar, pseudo-scalar, vector and axial vector background fields. The formulas
hold for completely general internal symmetry groups and general
configurations. In particular the scalar and pseudo-scalar fields need not be
on the chiral circle.

</DOC>
<DOC>
<DOCNO> 102764 </DOCNO>
State-estimators for chemical reaction networks of Feinberg-Horn-Jackson


  One of the most interesting questions in control theory is that of
constructing observers. Observers compute estimates of the internal states of a
dynamical system, using data provided by measurement probes or partial state
information. For linear systems, Luenberger observers (also known as
"deterministic Kalman filters" since they amount to Kalman filters designed
without regard to the statistics of measurement noise) provide a general
solution, but, for nonlinear systems, establishing generally applicable
conditions for existence and convergence of observers is an open and active
area of research. This paper provides a necessary and sufficient condition for
detectability, and an explicit construction of observers when this condition is
satisfied, for chemical reaction networks of the Feinberg-Horn-Jackson zero
deficiency type.

</DOC>
<DOC>
<DOCNO> 170806 </DOCNO>
Unconditionally Secure Quantum Coin Tossing via Entanglement Swapping


  An unconditionally secure quantum cion tossing protocol for two remote
participants via entangled swapping is presented. The security of this protocol
is guaranteed by the nonlocal property of quantum entanglement and the
classical complexity.

</DOC>
<DOC>
<DOCNO> 120810 </DOCNO>
HST Observations of Black Hole X-ray Transient Outbursts


  The Hubble Space Telescope has now observed four black hole X-ray transients
in outburst under an ongoing Target-of-Opportunity program: GRO J0422+32
(1994), GRO J1655-40 (1996), XTE J1859+226 (1999-2000) and XTE J1118+480
(2000). We summarise the highlights of this program to date, including a
diversity of spectral energy distributions, correlated X-ray/UV/optical rapid
variability and detailed UV spectroscopy.

</DOC>
<DOC>
<DOCNO> 101302 </DOCNO>
A note on interpolation in the generalized Schur class


  Realization theory for operator colligations on Pontryagin spaces is used to
study interpolation and factorization in generalized Schur classes. Several
criteria are derived which imply that a given function is almost the
restriction of a generalized Schur function. The role of realization theory in
coefficient problems is also discussed.

</DOC>
<DOC>
<DOCNO> 102009 </DOCNO>
A Generalized Numeration Base


  A Generalized Numeration Base is defined in this paper, and then particular
cases are presented, such as Prime Base, Square Base, m-Power Base, Factorial
Base, and operations in these bases. These bases are important for partitions
of integers into primes, squares, cubes, generally into m-powers, also into
factorials, and into any strictly increasing sequence.

</DOC>
<DOC>
<DOCNO> 7884 </DOCNO>
Many-body Correlation Effects in the Ultrafast Nonlinear Optical


  The dynamics of electrons and atoms interacting with intense and ultrashort
optical pulses presents an important problem in physics that cuts across
different materials such as semiconductors and metals. The currently available
laser pulses, as short as 5 fs, provide a time resolution shorter than the
dephasing and relaxation times in many materials. This allows for a systematic
study of many-body effects using nonlinear optical spectroscopy. In this review
article, we discuss the role of Coulomb correlations in the ultrafast dynamics
of modulation-doped quantum wells and metal nanoparticles. We focus in
particular on the manifestations of non-Markovian memory effects induced by
strong electron-hole and electron-plasmon correlations.

</DOC>
<DOC>
<DOCNO> 69865 </DOCNO>
Electroweak Sudakov at two loop level


  We investigate the Sudakov double logarithmic corrections to the form factor
of fermion in the SU(2)XU(1) electroweak theory. We adopt the familiar Feynman
gauge and present explicit calculations at the two loop level. We show that the
leading logarithmic corrections coming from the infrared singularities are
consistent with the "postulated" exponentiated electroweak Sudakov form factor.
The similarities and differences in the "soft" physics between the electroweak
theory and the unbroken non-abelian gauge theory (QCD) will be clarified.

</DOC>
<DOC>
<DOCNO> 84637 </DOCNO>
On Proper Time in General Relativity


  It is shown that the special relativistic relation ds=cd\tau between the
proper distance s and the proper time \tau is not generally correct when
spacetime is curved. The appropriate definition of \tau leads to the relation
ds=\sqrt{g_{t\prime t\prime}}cd\tau, where g_{t\prime t\prime} is the
coefficient of dt\prime^2 in the line element for the system S\prime of the
event. As a result of this, proper time is not invariant unless g_{t\prime
t\prime}is constant. A general relation in curved spacetime between d\tau and
dt is given. This relation reduces to the special relativistic one for flat
spacetime.

</DOC>
<DOC>
<DOCNO> 116269 </DOCNO>
Space-time geometry of quantum dielectrics


  Light experiences dielectric matter as an effective gravitational field and
matter experiences light as a form of gravity as well. Light and matter waves
see each other as dual space-time metrics, thus establishing a unique model in
field theory. Actio et reactio are governed by Abraham's energy-momentum tensor
and equations of state for quantum dielectrics.

</DOC>
<DOC>
<DOCNO> 102423 </DOCNO>
The BP<n> cohomology of elementary abelian groups


  In this paper we study E^*BV_k, where E=BP<m,n> is a cohomology theory with
coefficient ring F_p[v_m,...,v_n] (if m>0) or Z_(p)[v_1,...,v_n] (if m=0). We
use ideas from the theory of multiple level structures, developed in earlier
work of the author with John Greenlees. Our results apply when k is less than
or equal to w=n+1-m. If k<w we find that E^*BV_k has no v_m-torsion. When k=w,
we show that the v_m-torsion is annihilated by the ideal I_{n+1}=(v_m,...,v_n),
and that it is a free module on one generator over the ring
F_p[[x_0,...,x_{w-1}]]. We give three very different formulae for this
generator; it is not at all obvious that these give the same element, and we
only have a rather indirect proof of this.

</DOC>
<DOC>
<DOCNO> 84302 </DOCNO>
Simplicial minisuperspace models in the presence of a massive scalar


  We extend previous simplicial minisuperspace models to account for arbitrary
scalar coupling \eta R\phi^2

</DOC>
<DOC>
<DOCNO> 122665 </DOCNO>
Observational Estimates for the Mass-Loss Rates of Alpha Centauri and


  We study H I Lyman-alpha absorption observed by the Hubble Space Telescope
toward the nearby binary system Alpha Cen (G2 V+K0 V) and its distant companion
star Proxima Cen (M5.5 Ve). Absorption from heliospheric H I heated by the
solar wind/ISM interaction is observed toward both Alpha Cen and Proxima Cen.
Absorption from analogous "astrospheric" material surrounding the stars is
detected toward Alpha Cen, but not Proxima Cen. The nondetection of
astrospheric absorption toward Proxima Cen suggests that the stellar wind of
Proxima Cen must be significantly weaker than that of the Alpha Cen system. We
use hydrodynamic models of the astrospheres computed assuming different
mass-loss rates to predict astrospheric Lyman-alpha absorption for comparison
with the observations. The model that best matches the Alpha Cen data has a
mass-loss rate of twice the solar rate, and the models suggest an upper limit
of 0.2 solar for Proxima Cen. Finally, we note that the heliospheric absorption
observed toward Proxima Cen in 2000 May is identical to the heliospheric
absorption observed toward Alpha Cen in 1995 May, implying that the structure
of the outer heliosphere does not change significantly during the solar
activity cycle.

</DOC>
<DOC>
<DOCNO> 170445 </DOCNO>
Violation of Bell inequalities in classical continuum models


  A classical local particle hidden-variable model for quantum theory is taken
here not to be possible because of the experimental violation of Bell
inequalities, whereas it has been known since 1976 that a classical local
continuum hidden-variable model for quantum field theory is not ruled out,
because of what has become known as the "conspiracy" loophole. Although Bell's
view, and the conventional view, is that classical continuum models are not
impossible but implausible, this paper argues that they are plausible, and then
pursues the consequences of other requirements on them, including the
Kochen-Specker paradox and measurement. Since classical continuum models are
relatively intractable, a "classical continuum interpretation" for quantum
field theory is also introduced.

</DOC>
<DOC>
<DOCNO> 121900 </DOCNO>
Constraints on Omega_B, Omega_m and h from MAXIMA and BOOMERANG


  We analyse the BOOMERANG and MAXIMA results in the context of models with
$\Omega_{\rm Total} = 1$ and $n_s = 1$. We attempt to constrain three other
parameters---$h$, $\Omega_B$, and $\Omega_m$---from these observations. We show
that: (a) the value of $\Omega_B h^2$ is too high to be compatible with
primordial nucleosynthesis observations at 95% confidence level (b) universe
with age greater than $ 12 \rm Gyr$ is ruled out at 95% confidence level and
(c) the value of $\Omega_m h$ is too high to be compatible with the shape of
the power spectrum of gravitational clustering. In effect, our analysis shows
that models with $\Omega_{\rm Total} = 1$ and $n_s = 1$ are ruled out by
BOOMERANG and MAXIMA observations.

</DOC>
<DOC>
<DOCNO> 122582 </DOCNO>
Kaon Condensation in Neutron Stars


  We discuss the kaon-nucleon interaction and its consequences for the change
of the properties of the kaon in the medium. The onset of kaon condensation in
neutron stars under various scenarios as well its effects for neutron star
properties are reviewed.

</DOC>
<DOC>
<DOCNO> 85621 </DOCNO>
Superinflation, quintessence, and the avoidance of the initial


  We consider the dynamics of a spatially flat universe dominated by a
self-interacting nonminimally coupled scalar field. The structure of the phase
space and complete phase portraits for the conformal coupling case are given.
It is shown that the non-minimal coupling modifies drastically the dynamics of
the universe. New cosmological behaviors are identified, including
superinflation ($\dot{H}>0$), avoidance of big bang singularities through
classical birth of the universe from empty Minkowski space, and spontaneous
entry into and exit from inflation. The relevance of this model to the
description of quintessence is discussed.

</DOC>
<DOC>
<DOCNO> 84279 </DOCNO>
Hamiltonian formulation of teleparallel theories of gravity in the time


  We consider the most general class of teleparallel theories of gravity
quadratic in the torsion tensor, and carry out a detailed investigation of its
Hamiltonian formulation in the time gauge. Such general class is given by a
three-parameter family of theories. A consistent implementation of the Legendre
transform reduces the original theory to a one-parameter theory determined in
terms of first class constraints. The free parameter is fixed by requiring the
Newtonian limit. The resulting theory is the teleparallel equivalent of general
relativity.

</DOC>
<DOC>
<DOCNO> 11333 </DOCNO>
Observation of resonance trapping in an open microwave cavity


  The coupling of a quantum mechanical system to open decay channels has been
theoretically studied in numerous works, mainly in the context of nuclear
physics but also in atomic, molecular and mesoscopic physics. Theory predicts
that with increasing coupling strength to the channels the resonance widths of
all states should first increase but finally decrease again for most of the
states. In this letter, the first direct experimental verification of this
effect, known as resonance trapping, is presented. In the experiment a
microwave Sinai cavity with an attached waveguide with variable slit width was
used.

</DOC>
<DOC>
<DOCNO> 178506 </DOCNO>
Isoscalar dipole mode in relativistic random phase approximation


  The isoscalar giant dipole resonance structure in $^{208}$Pb is calculated in
the framework of a fully consistent relativistic random phase approximation,
based on effective mean-field Lagrangians with nonlinear meson self-interaction
terms. The results are compared with recent experimental data and with
calculations performed in the Hartree-Fock plus RPA framework. Two basic
isoscalar dipole modes are identified from the analysis of the velocity
distributions. The discrepancy between the calculated strength distributions
and current experimental data is discussed, as well as the implications for the
determination of the nuclear matter incompressibility.

</DOC>
<DOC>
<DOCNO> 122609 </DOCNO>
CMB Signatures of a Primordial Magnetic Field


  A primordial stochastic magnetic field will induce temperature and
polarization fluctuations in the cosmic microwave background. We outline a
calculation of the resulting fluctuation power spectra and present numerical
results.

</DOC>
<DOC>
<DOCNO> 117088 </DOCNO>
Cold collisions between atoms in optical lattices


  We have simulated binary collisions between atoms in optical lattices during
Sisyphus cooling. Our Monte Carlo Wave Function simulations show that the
collisions selectively accelerate mainly the hotter atoms in the thermal
ensemble, and thus affect the steady state which one would normally expect to
reach in Sisyphus cooling without collisions.

</DOC>
<DOC>
<DOCNO> 118059 </DOCNO>
Radio Supernovae and GRB 980425


  Study of radio supernovae (RSNe) over the past 20 years includes two dozen
detected objects and more than 100 upper limits. From this work we are able to
identify classes of radio properties, demonstrate conformance to and deviations
from existing models, estimate the density and structure of the circumstellar
material and, by inference, the evolution of the presupernova stellar wind, and
reveal the last stages of stellar evolution before explosion. It is also
possible to detect ionized hydrogen along the line of sight, to demonstrate
binary properties of the stellar system, and to show clumpiness of the
circumstellar material. More speculatively, it may be possible to provide
distance estimates to radio supernovae.
  The interesting and unusual radio supernova SN 1998bw, which is thought to be
related to the gamma-ray burst GRB 980425, is discussed in particular detail.
Its radio properties are compared and contrasted with those of other known
RSNe.

</DOC>
<DOC>
<DOCNO> 116818 </DOCNO>
Heart Rate Variability: Measures and Models


  We focus on various measures of the fluctuations of the sequence of intervals
between beats of the human heart, and how such fluctuations can be used to
assess the presence or likelihood of cardiovascular disease. We examine sixteen
such measures and their suitability for correctly classifying heartbeat records
of various lengths as normal or revealing the presence of cardiac dysfunction,
particularly congestive heart failure. Using receiver-operating-characteristic
analysis we demonstrate that scale-dependent measures prove substantially
superior to scale-independent ones. The wavelet-transform standard deviation at
a scale near 32 heartbeat intervals, and its spectral counterpart near 1/32
cycles/interval, turn out to provide reliable results using heartbeat records
just minutes long. We further establish for all subjects that the human
heartbeat has an underlying stochastic origin rather than arising from a
chaotic attractor. Finally, we develop a mathematical point process that
emulates the human heartbeat time series for both normal subjects and
heart-failure patients.

</DOC>
<DOC>
<DOCNO> 178551 </DOCNO>
A number projected model with generalized pairing interaction


  A mean-field model with a generalized pairing interaction that accounts for
neutron-proton pairing is presented. Both the BCS as well as number-projected
solutions of the model are presented. For the latter case the Lipkin-Nogami
projection technique was extended to encompass the case of non-separable
proton-neutron systems. The influence of the projection on various pairing
phases is discussed. In particular, it is shown that number-projection allows
for mixing of different pairing phases but, simultanously, acts destructively
on the proton-neutron correlations. The basic implications of proton-neutron
pairing correlations on nuclear masses are discussed. It is shown that these
correlations may provide a natural microscopic explanation of the Wigner energy
lacking in mean-field models. A possible phase transition from isovector to
isoscalar pairing condensate at high angular momenta is also discussed. In
particular predictions for the dynamical moments of inertia for the
superdeformed band in $^{88}$Ru are given.

</DOC>
<DOC>
<DOCNO> 100962 </DOCNO>
Vassiliev invariants for braids on surfaces


  We show that Vassiliev invariants separate braids on a closed oriented
surface, and we exhibit an universal Vassiliev invariant for these braids in
terms of chord diagrams labeled by elements of the fundamental group of the
considered surface.

</DOC>
<DOC>
<DOCNO> 117323 </DOCNO>
Differential cross sections for elastic and inelastic


  We report results of differential cross sections for elastic scattering,
target-elastic Ps excitations and target-inelastic excitation of hydrogen in a
five-state coupled-channel model allowing for Ps(1s)H(2s,2p) and Ps(2s,2p)H(1s)
excitations using a recently proposed time-reversal-symmetric regularized
electron-exchange model potential. The present model yields a singlet Ps-H
S-wave resonance at 4.01 eV of width 0.15 eV and a P-wave resonance at 5.08 eV
of width 0.004 eV. We also study the effect of the inclusion of the excited Ps
and H states on the convergence of the coupled-channel scheme.

</DOC>
<DOC>
<DOCNO> 69610 </DOCNO>
Current Issues In Quarkonium Production


  As a stringent test of the nonrelativistic QCD factorization approach for
inclusive heavy-quarkonium production in high-energy hadron collision, the
polarized heavy-quarkonium production at the Tevatron is discussed. The
polarization of prompt J/psi at the Tevatron is predicted within the
nonrelativistic QCD factorization framework. The contribution from radiative
decays of P-wave charmonium states decreases, but does not eliminate, the
transverse polarization at large transverse momentum. The prediction agrees
with measurements from the CDF collaboration at intermediate values of p_T, but
disagrees at the large values of p_T measured. Recent preliminary data of heavy
quarkonia from CDF and theoretical/experimental prospects related to the Run II
heavy quarkonium physics are also discussed.

</DOC>
<DOC>
<DOCNO> 80926 </DOCNO>
Hopf defects as seeds for monopole loops


  We investigate the relation between instantons and monopoles in the Laplacian
Abelian Gauge using analytical methods in the continuum. Our starting point is
the fact that the 't Hooft instanton with its high symmetry leads to a
pointlike defect with Hopf invariant one. In order to generalise this result we
partly break the symmetry by a local perturbation. We find that for generic
configurations near the 't Hooft instanton the defects become loops. The
analytical results show explicitly that these defects are magnetic monopoles
with unit charge. In addition, the monopoles are twisted to account for the
instanton number of the background.

</DOC>
<DOC>
<DOCNO> 40544 </DOCNO>
Nonmesonic decay of the Lambda-hyperon in hypernuclei produced by p+Au


  The lifetime of the Lambda-hyperon for the nonmesonic decay Lambda N ---> N N
has been determined by a measurement at COSY Juelich of the delayed fission of
heavy hypernuclei produced in proton - Au collisions at T_p=1.9 GeV. It is
found that heavy hypernuclei with mass numbers A= 180 +- 5 and atomic numbers
Z= 74 +-2 fission with a lifetime
      130ps +- 13ps (stat.) +- 15ps (syst.) . This value together with the
results obtained for other heavy hypernuclei in previous investigations
indicates (on the confidence level of 0.9) a violation of the phenomenological
Delta I = 1/2 rule for Lambda N ---> NN transitions as known from the weak
mesonic decays of kaons and hyperons. PACS:
      {13.30.-a}{Decays of baryons}
      {13.75.Ev}{Hyperon-nucleon interaction}
      {21.80}{Hypernuclei}
      {25.80.Pw}{Hyperon-induced reactions}

</DOC>
<DOC>
<DOCNO> 151781 </DOCNO>
Lie algebraic structures in integrable models, affine Toda field theory


  The most prominent class of integrable quantum field theories in 1+1
dimensions is affine Toda theory. Distinguished by a rich underlying Lie
algebraic structure these models have in recent years attracted much attention
not only as test laboratories for non-perturbative methods in quantum field
theory but also in the context of off-critical models. After a short
introduction the mathematical preliminaries such as root systems, Coxeter
geometry, dual algebras, q-deformed Coxeter elements and q-deformed Cartan
matrices are introduced. Using this mathematical framework the bootstrap
analysis of the affine Toda S-matrices with real coupling is performed and
several universal Lie algebraic formulae proved. The Lie algebraic methods are
then extended to define a new class of colour valued S-matrices and also here
universal expressions are derived. The second part of the thesis presents a
detailed analysis of the high-energy regime of the integrable models discussed
in the first part. By means of the thermodynamic Bethe ansatz the central
charges of the ultraviolet conformal field theories are calculated and in case
of affine Toda theories also the first order term in the scaling function is
analytically obtained. For the colour valued S-matrices the connection to WZNW
coset models is discussed. A particular subclass of them, the so-called
Homogeneous Sine-Gordon models, is investigated in some detail and it is found
that the presence of unstable particles in these theories gives rise to a
staircase pattern in the corresponding scaling function. This thesis summarizes
the results of previously published articles listed in the introduction.

</DOC>
<DOC>
<DOCNO> 85106 </DOCNO>
Born-Infeld electrodynamics: Clifford numbers and spinor representations


  Clifford numbers formalism for Maxwell equations system is considered. The
Clifford imaginary unit for space-time is introduced as coordinate independent
form of fully antisymmetric fourth-rank tensor. The representation of Maxwell
equations system in massless Dirac equation form is considered. In this
connection we consider two approach to the invariance of Dirac equation as
respects the Lorentz transformations. According the first approach the unknown
column is invariant and according the second approach it has the transformation
properties known as spinorial ones. Clifford numbers representation for
nonlinear electrodynamics equations system is obtained. From this
representation we obtain the nonlinear like Dirac equation which is the form of
nonlinear electrodynamics equations. As the special case we have the
appropriate representations for Born-Infeld nonlinear electrodynamics.

</DOC>
<DOC>
<DOCNO> 13391 </DOCNO>
Organization of Growing Random Networks


  The organizational development of growing random networks is investigated.
These growing networks are built by adding nodes successively and linking each
to an earlier node of degree k with attachment probability A_k. When A_k grows
slower than linearly with k, the number of nodes with k links, N_k(t), decays
faster than a power-law in k, while for A_k growing faster than linearly in k,
a single node emerges which connects to nearly all other nodes. When A_k is
asymptotically linear, N_k(t) tk^{-nu}, with nu dependent on details of the
attachment probability, but in the range 2<nu<infty. The combined age and
degree distribution of nodes shows that old nodes typically have a large
degree. There is also a significant correlation in the degrees of neighboring
nodes, so that nodes of similar degree are more likely to be connected. The
size distributions of the in-components and out-components of the network with
respect to a given node -- namely, its "descendants" and "ancestors" -- are
also determined. The in-component exhibits a robust s^{-2} power-law tail,
where s is the component size. The out component has a typical size of order ln
t and it provides basic insights about the genealogy of the network.

</DOC>
<DOC>
<DOCNO> 122765 </DOCNO>
Detection of a Corrugated Velocity Pattern in the Spiral Galaxy NGC 5427


  Here we report the detection, in Halpha emission, of a radial corrugation in
the velocity field of the spiral galaxy NGC 5427. The central velocity of the
Halpha line displays coherent, wavy-like variations in the vicinity of the
spiral arms. The spectra along three different arm segments show that the
maximum amplitude of the sinusoidal line variations are displaced some 500 pc
from the central part of the spiral arms. The peak blueshifted velocities
appear some 500 pc upstream the arm, whereas the peak redshifted velocities are
located some 500 pc downstream the arm. This kinematical behavior is similar to
the one expected in a galactic bore generated by the interaction of a spiral
density wave with a thick gaseous disk, as recently modeled by Martos & Cox
(1998).

</DOC>
<DOC>
<DOCNO> 69670 </DOCNO>
Diffractive structure function at very small beta and unitarity


  Starting from the phenomenologically successful color dipole representation
of the diffractive structure function, we identify the dominant contribution to
the diffractive cross section at small beta. The beta dependence is calculated
taking advantage of the Regge factorization properties of the hard mechanism
which drives the dependence on the diffractive mass. We impose the unitarity
constraints on the $x_\Pom$-dependence and comment on the screening corrections
to $F_{2p}$.

</DOC>
<DOC>
<DOCNO> 85346 </DOCNO>
Optical noise correlations and beating the standard quantum limit in


  The uncertainty principle, applied naively to the test masses of a
laser-interferometer gravitational-wave detector, produces a Standard Quantum
Limit (SQL) on the interferometer's sensitivity. It has long been thought that
beating this SQL would require a radical redesign of interferometers. However,
we show that LIGO-II interferometers, currently planned for 2006, can beat the
SQL by as much as a factor two over a bandwidth \Delta f \sim f, if their
thermal noise can be pushed low enough. This is due to dynamical correlations
between photon shot noise and radiation-pressure noise, produced by the LIGO-II
signal-recycling mirror.

</DOC>
<DOC>
<DOCNO> 71051 </DOCNO>
Perturbative QCD analysis of near-to-planar three jet events


  We present the all-order resummed thrust minor distribution as a measure of
aplanarity in three-jet events.

</DOC>
<DOC>
<DOCNO> 84947 </DOCNO>
Distinguishing Marks of Simply-connected Universes


  A statistical quantity suitable for distinguishing simply-connected
Robertson-Walker (RW) universes is introduced, and its explicit expressions for
the three possible classes of simply-connected RW universes with an uniform
distribution of matter are determined. Graphs of the distinguishing mark for
each class of RW universes are presented and analyzed.There sprout from our
results an improvement on the procedure to extract the topological signature of
multiply-connected RW universes, and a refined understanding of that
topological signature of these universes studied in previous works.

</DOC>
<DOC>
<DOCNO> 100959 </DOCNO>
Stability results for solutions of obstacle problems with measure data


  In this paper we study the continuous dependence with respect to obstacles
for obstacle problems with measure data. This is deeply investigated
introducing a suitable type of convergence, which gives stability under very
general hypotheses. Moreover stability with respect to H^1 and uniform
convergent obstacles is proved.

</DOC>
<DOC>
<DOCNO> 9937 </DOCNO>
A cluster algorithm for Potts models with fixed spin densities


  A cluster algorithm is presented for the simulation of the q-state Potts
models in which the number of spins is conserved in each state. The algorithm
constructs Fortuin-Kasteleyn cluster configurations from spin configurations,
in a way identical to the Swendsen-Wang algorithm; the spin assignment to these
clusters is however different, and conserves the number of spins for each
state. Compared to traditional non-local spin-exchange algorithms, the cluster
algorithm presented here suffers less from critical slowing down, and
consequently is more efficient near the critical temperature.

</DOC>
<DOC>
<DOCNO> 100383 </DOCNO>
Computational Arithmetic Geometry I: Sentences Nearly in the Polynomial


  We consider the average-case complexity of some otherwise undecidable or open
Diophantine problems. More precisely, consider the following: (I) Given a
polynomial f in Z[v,x,y], decide the sentence \exists v \forall x \exists y
f(v,x,y)=0, with all three quantifiers ranging over N (or Z). (II) Given
polynomials f_1,...,f_m in Z[x_1,...,x_n] with m>=n, decide if there is a
rational solution to f_1=...=f_m=0. We show that, for almost all inputs,
problem (I) can be done within coNP. The decidability of problem (I), over N
and Z, was previously unknown. We also show that the Generalized Riemann
Hypothesis (GRH) implies that, for almost all inputs, problem (II) can be done
via within the complexity class PP^{NP^NP}, i.e., within the third level of the
polynomial hierarchy. The decidability of problem (II), even in the case m=n=2,
remains open in general.
  Along the way, we prove results relating polynomial system solving over C, Q,
and Z/pZ. We also prove a result on Galois groups associated to sparse
polynomial systems which may be of independent interest. A practical
observation is that the aforementioned Diophantine problems should perhaps be
avoided in the construction of crypto-systems.

</DOC>
<DOC>
<DOCNO> 11874 </DOCNO>
Decay properties of the one-particle Green function in real space and


  The decay properties of the one-particle Green function in real space and
imaginary time are systematically studied for solids. I present an analytic
solution for the homogeneous electron gas at finite and at zero temperature as
well as asymptotic formulas for real metals and insulators that allow an
analytic treatment in electronic-structure calculations based on a space-time
representation. The generic dependence of the decay constants on known system
parameters is used to compare the scaling of reciprocal-space algorithms for
the GW approximation and the space-time method.

</DOC>
<DOC>
<DOCNO> 121974 </DOCNO>
Halo Formation in Warm Dark Matter Models


  Discrepancies have emerged between the predictions of standard cold dark
matter (CDM) theory and observations of clustering on sub-galactic scales. Warm
dark matter (WDM) is a simple modification of CDM in which the dark matter
particles have initial velocities due either to their having decoupled as
thermal relics, or having been formed via non-equilibrium decay. We investigate
the nonlinear gravitational clustering of WDM with a high resolution N-body
code, and identify a number of distinctive observational signatures. Relative
to CDM, halo concentrations and core densities are lowered, core radii are
increased, and large halos emerge with far fewer low mass satellites. The
number of small halos is suppressed, and those present are formed by `top down'
fragmentation of caustics, as part of a `cosmic web' connecting massive halos.
Few small halos form outside this web. If we identify small halos with dwarf
galaxies, their number, spatial distribution, and formation epoch appear in
better agreement with the observations for WDM than they are for CDM.

</DOC>
<DOC>
<DOCNO> 83362 </DOCNO>
Bunsetsu Identification Using Category-Exclusive Rules


  This paper describes two new bunsetsu identification methods using supervised
learning. Since Japanese syntactic analysis is usually done after bunsetsu
identification, bunsetsu identification is important for analyzing Japanese
sentences. In experiments comparing the four previously available
machine-learning methods (decision tree, maximum-entropy method, example-based
approach and decision list) and two new methods using category-exclusive rules,
the new method using the category-exclusive rules with the highest similarity
performed best.

</DOC>
<DOC>
<DOCNO> 117026 </DOCNO>
Rotation in liquid $^4$He: Lessons from a toy model


  This paper presents an analysis of a model problem, consisting of two
interacting rigid rings, for the rotation of molecules in liquid $^4$He. Due to
Bose symmetry, the excitation of the rotor corresponding to a ring of N helium
atoms is restricted to states with integer multiples of N quanta of angular
momentum. This minimal model shares many of the same features of the rotational
spectra that have been observed for molecules in nanodroplets of $\approx 10^3
- 10^4$ helium atoms. In particular, this model predicts, for the first time,
the very large enhancement of the centrifugal distortion constants that have
been observed experimentally. It also illustrates the different effects of
increasing rotational velocity by increases in angular momentum quantum number
or by increasing the rotational constant of the molecular rotor. It is found
that fixed node, diffusion Monte Carlo and a hydrodynamic model provide upper
and lower bounds on the size of the effective rotational constant of the
molecular rotor when coupled to the helium.

</DOC>
<DOC>
<DOCNO> 152641 </DOCNO>
Comments on the Thermodynamics of Little String Theory


  We study the high energy thermodynamics of Little String Theory, using its
holographic description. This leads to the entropy-energy relation $S=\beta_H
E+\alpha\log E+O(1/E)$. We compute $\alpha$ and show that it is negative; as a
consequence, the high energy thermodynamics is unstable. We exhibit a mode
localized near the horizon of the black brane, which has winding number one
around Euclidean time and a mass that vanishes at large $E$ (or
$\beta\to\beta_H$). We argue that the high temperature phase of the theory
involves condensation of this mode.

</DOC>
<DOC>
<DOCNO> 102692 </DOCNO>
Cohomology of Siegel Varieties with p-adic integral coefficients and


  Under the assumption that Galois representations associated to Siegel modular
forms exist (it is known only for genus at most 2), we show that the cohomology
with p-adic integral coefficients of Siegel Varieties, when localized at a
non-Eisenstein maximal ideal of the Hecke algebra, is torsion-free, provided
the prime p is large with the respect to the weight of the coefficient system.
The proof uses p-adic Hodge theory, the dual BGG complex modulo p in order to
compute the Hodge-Tate weights for the mod p cohomology. We apply this result
to the construction of Hida p-adic families for symplectic groups and to the
first step in the construction of a Taylor-Wiles system for these groups.

</DOC>
<DOC>
<DOCNO> 7923 </DOCNO>
Quantization of Hall Conductance in Double Exchange Systems: Topology


  We study quantization conditions of the Hall conductivity for a two
dimensional system described by a double exchange Hamiltonian with and without
an external magnetic field. This is obtained by an extension of the topological
arguments familiar from the theory of the integer quantum Hall effect. The
quantization conditions are related to spontaneous breaking of spin O(3),
time-reversal, and spin chiral symmetries. Extension to systems with higher
dimensions is briefly discussed.

</DOC>
<DOC>
<DOCNO> 70744 </DOCNO>
Large Two-Loop Contributions to g-2 from a Generic Pseudoscalar Boson


  We calculate the dominant contributions to the muon $g-2$ at the two-loop
level due to a generic pseudoscalar boson that may exist in any exotic Higgs
sector in most extensions of the standard model. The leading effect comes from
diagrams of the Barr-Zee type. A sufficiently light pseudoscalar Higgs boson
can give rise to contribution as large as the electroweak contribution which is
measurable in the next round of $g-2$ experiment. Through the contribution we
calculated here, the anticipated improved data in the recent future on the muon
$g-2$ can put the best limit on the possible existence of a light pseudoscalar
boson in physics beyond the standard model.

</DOC>
<DOC>
<DOCNO> 152542 </DOCNO>
String Theory on AdS_3 and Symmetric Products


  We consider string theory on a background of the form AdS_3 x N. Our aim is
to give a description of the dual CFT in a general set up. With the requirement
that we have N=2 supersymmetry in spacetime, we provide evidence that the dual
CFT is in the moduli space of a certain symmetric product M^p/S_p. On the way
to show this, we reproduce some recent results on string propagation on AdS_3
and extend them to the superstring.

</DOC>
<DOC>
<DOCNO> 83440 </DOCNO>
Faster Evaluation of Multidimensional Integrals


  In a recent paper Keister proposed two quadrature rules as alternatives to
Monte Carlo for certain multidimensional integrals and reported his test
results. In earlier work we had shown that the quasi-Monte Carlo method with
generalized Faure points is very effective for a variety of high dimensional
integrals occurng in mathematical finance. In this paper we report test results
of this method on Keister's examples of dimension 9 and 25, and also for
examples of dimension 60, 80 and 100. For the 25 dimensional integral we
achieved accuracy of 0.01 with less than 500 points while the two methods
tested by Keister used more than 220,000 points. In all of our tests, for n
sample points we obtained an empirical convergence rate proportional to n^{-1}
rather than the n^{-1/2} of Monte Carlo.

</DOC>
<DOC>
<DOCNO> 118976 </DOCNO>
Spectral Templates from Multicolor Redshift Surveys


  Understanding how the physical properties of galaxies (e.g. their spectral
type or age) evolve as a function of redshift relies on having an accurate
representation of galaxy spectral energy distributions. While it has been known
for some time that galaxy spectra can be reconstructed from a handful of
orthogonal basis templates, the underlying basis is poorly constrained. The
limiting factor has been the lack of large samples of galaxies (covering a wide
range in spectral type) with high signal-to-noise spectrophotometric
observations. To alleviate this problem we introduce here a new technique for
reconstructing galaxy spectral energy distributions directly from samples of
galaxies with broadband photometric data and spectroscopic redshifts.
Exploiting the statistical approach of the Karhunen-Loeve expansion, our
iterative training procedure increasingly improves the eigenbasis, so that it
provides better agreement with the photometry. We demonstrate the utility of
this approach by applying these improved spectral energy distributions to the
estimation of photometric redshifts for the HDF sample of galaxies. We find
that in a small number of iterations the dispersion in the photometric
redshifts estimator (a comparison between predicted and measured redshifts) can
decrease by up to a factor of 2.

</DOC>
<DOC>
<DOCNO> 68631 </DOCNO>
Dirac Strings and Monopoles in the Continuum Limit of SU(2) Lattice


  Magnetic monopoles are known to emerge as leading non-perturbative
fluctuations in the lattice version of non-Abelian gauge theories in some
gauges. In terms of the Dirac quantization condition, these monopoles have
magnetic charge |Q_M|=2. Also, magnetic monopoles with |Q_M|=1 can be
introduced on the lattice via the 't Hooft loop operator. We consider the
|Q_M|=1,2 monopoles in the continuum limit of the lattice gauge theories. To
substitute for the Dirac strings which cost no action on the lattice, we allow
for singular gauge potentials which are absent in the standard continuum
version. Once the Dirac strings are allowed, it turns possible to find a
solution with zero action for a monopole--antimonopole pair. This implies
equivalence of the standard and modified continuum versions in perturbation
theory. To imitate the nonperturbative vacuum, we introduce then a nonsingular
background. The modified continuum version of the gluodynamics allows in this
case for monopoles with finite non-vanishing action. Using similar techniques,
we construct the 't Hooft loop operator in the continuum and predict its
behavior at small and large distances both at zero and high temperatures.

</DOC>
<DOC>
<DOCNO> 119639 </DOCNO>
The European Large Area ISO Survey: Latest Result


  We present some recent results from the European Large Area ISO Survey
(ELAIS). This survey was the largest non-serendipitous ISO field survey. A
preliminary reduction has recently been completed and catalogues of sources
released to the community. Early results show strongly evolving source counts.
A comprehensive identification programme is underway and a number of extremely
luminous objects have already been discovered. This survey provides an exciting
legacy from the ISO mission and (amongst many goals) will allow us to provide
important constraints on the obscured star-formation history of the Universe.

</DOC>
<DOC>
<DOCNO> 67906 </DOCNO>
Anti-deSitter Vacua of Gauged Supergravities with 8 Supercharges


  We investigate supersymmetric extrema of Abelian gauged supergravity theories
with non-trivial vector multiplets and 8 supercharges in four and five
dimensions. The scalar fields of these models parameterize a manifold
consisting of disconnected branches and restricting to the case where this
manifold has a non-singular metric we show that on every branch there can be at
most one extremum, which is a local maximum (for W>0) or a minimum (for W<0) of
the superpotential W. Therefore, these supergravity models do not allow for
regular domain wall solutions interpolating between different extrema of the
superpotential and the space-time transverse to the wall asymptotically always
approaches the boundary of AdS (UV-fixed points in a dual field theory).

</DOC>
<DOC>
<DOCNO> 40514 </DOCNO>
Open Charm and Beauty Production at HERA


  Selected new results from the H1 and ZEUS collaborations on $ep$ interactions
at 300 - 318 GeV centre-of-mass energy are presented. The full pre-upgrade
integrated luminosity of HERA of 110 pb$^{-1}$ is used. Charm cross sections
are measured up to high values of $x_B$ and $Q^2$ and are found to be well
described by NLO QCD in the 3 flavour scheme. Orbitally excited $D$ mesons are
observed; radial excitations are searched for, but are not seen. The first $b$
cross section measurement is confirmed with a lifetime based method,
establishing the excess over NLO QCD.

</DOC>
<DOC>
<DOCNO> 99937 </DOCNO>
$C_{\lambda}$-extended oscillator algebras and some of their


  $C_{\lambda}$-extended oscillator algebras generalizing the Calogero-Vasiliev
algebra, where $C_{\lambda}$ is the cyclic group of order $\lambda$, are
studied both from mathematical and applied viewpoints. Casimir operators of the
algebras are obtained, and used to provide a complete classification of their
unitary irreducible representations under the assumption that the number
operator spectrum is nondegenerate. Deformed algebras admitting Casimir
operators analogous to those of their undeformed counterparts are looked for,
yielding three new algebraic structures. One of them includes the Brzezi\'nski
{\em et al.} deformation of the Calogero-Vasiliev algebra as a special case. In
its bosonic Fock-space representation, the realization of
$C_{\lambda}$-extended oscillator algebras as generalized deformed oscillator
ones is shown to provide a bosonization of several variants of supersymmetric
quantum mechanics: parasupersymmetric quantum mechanics of order $p =
\lambda-1$ for any $\lambda$, as well as pseudosupersymmetric and
orthosupersymmetric quantum mechanics of order two for $\lambda=3$.

</DOC>
<DOC>
<DOCNO> 178635 </DOCNO>
On the Delta-Delta component of the deuteron in the Nambu-Jona-Lasinio


  The probability P(Delta-Delta) to find the Delta-Delta component inside the
deuteron, where Delta stands for the Delta(1232) resonance, is calculated in
the Nambu-Jona-Lasinio model of light nuclei. We obtain P(Delta-Delta) = 0.3%.
This prediction agrees good with the experimental estimate P(Delta-Delta) <
0.4% at 90% of CL (D. Allasia et al., Phys. Lett. B174 (1986) 450).

</DOC>
<DOC>
<DOCNO> 102048 </DOCNO>
Extensions of algebraic function fields with complete splitting of all


  We introduce the notion of "quasi-symmetric" polynomials, which is a
generalization of the notion of symmetry, and is particularly suited to the
setting of polynomial rings over finite fields. The properties of this new
class of functions are studied. It is then shown that quasi-symmetric
polynomials are very useful in splitting rational places in extensions of
function fields over finite fields and thus may be used in constructing
extensions with many rational places.

</DOC>
<DOC>
<DOCNO> 118079 </DOCNO>
Radially truncated galactic discs


  We present the first results of a systematic analysis of radially truncated
exponential discs for four galaxies of a complete sample of disc-dominated
edge-on spiral galaxies. The discs of our sample galaxies are truncated at
similar radii on either side of their centres. With possible the exception of
the disc of ESO 416-G25, it appears that the truncations in our sample galaxies
are closely symmetric, in terms of both their sharpness and the truncation
length. However, the truncations occur over a larger region and not as abruptly
as found in previous studies. We show that the truncated luminosity
distributions of our sample galaxies, if also present in the mass
distributions, comfortably meet the requirements for longevity. The formation
and maintenance of disc truncations are likely closely related to stability
requirements for galactic discs.

</DOC>
<DOC>
<DOCNO> 83288 </DOCNO>
Using compression to identify acronyms in text


  Text mining is about looking for patterns in natural language text, and may
be defined as the process of analyzing text to extract information from it for
particular purposes. In previous work, we claimed that compression is a key
technology for text mining, and backed this up with a study that showed how
particular kinds of lexical tokens---names, dates, locations, etc.---can be
identified and located in running text, using compression models to provide the
leverage necessary to distinguish different token types (Witten et al., 1999)

</DOC>
<DOC>
<DOCNO> 169758 </DOCNO>
Light Pulse Squeezed State Formation In Medium With The Relaxation Kerr


  The consistent theory of formation of pulsed squeezed states as a result of
self-action of ultrashort light pulse in the medium with relaxation Kerr
nonlinearity has been developed. A simple method to form the ultrashort light
pulse with sub-Poissonian photon statistics is analyzed too.

</DOC>
<DOC>
<DOCNO> 83312 </DOCNO>
Efficient cache use for stencil operations on structured discretization


  We derive tight bounds on cache misses for evaluation of explicit stencil
operators on structured grids. Our lower bound is based on the isoperimetrical
property of the discrete octahedron. Our upper bound is based on good surface
to volume ratio of a parallelepiped spanned by a reduced basis of the inter-
ference lattice of a grid. Measurements show that our algorithm typically
reduces the number of cache misses by factor of three relative to a compiler
optimized code. We show that stencil calculations on grids whose interference
lattice have a short vector feature abnormally high numbers of cache misses. We
call such grids unfavorable and suggest to avoid these in computations by
appropriate padding. By direct measurements on MIPS R10000 we show a good
correlation of abnormally high cache misses and unfavorable three-dimensional
grids.

</DOC>
<DOC>
<DOCNO> 9921 </DOCNO>
Finite size effects on the phase diagram of a binary mixture confined


  A symmetrical binary mixture AB that exhibits a critical temperature T_{cb}
of phase separation into an A-rich and a B-rich phase in the bulk is considered
in a geometry confined between two parallel plates a distance D apart. It is
assumed that one wall preferentially attracts A while the other wall
preferentially attracts B with the same strength (''competing walls''). In the
limit $D\to \infty$, one then may have a wetting transition of first order at
a temperature T_{w}, from which prewetting lines extend into the one phase
region both of the A-rich and the B-rich phase. It is discussed how this phase
diagram gets distorted due to the finiteness of D% : the phase transition at
T_{cb} immediately disappears for D<\infty due to finite size rounding,
and the phase diagram instead exhibit two two-phase coexistence regions in a
temperature range T_{trip}<T<T_{c1}=T_{c2}. In the limit D\to \infty T_{c1},T_{c2} become the prewetting critical points and T_{trip}\to
T_{w}.
  For small enough D it may occur that at a tricritical value D_{t} the
temperatures T_{c1}=T_{c2} and T_{trip} merge, and then for D<D_{t} there
is a single unmixing critical point as in the bulk but with T_{c}(D) near
T_{w}. As an example, for the experimentally relevant case of a polymer
mixture a phase diagram with two unmixing critical points is calculated
explicitly from self-consistent field methods.

</DOC>
<DOC>
<DOCNO> 40252 </DOCNO>
High order PT calculations for heavy quarks near threshold


  Results of analytical calculations for heavy quark systems in higher orders
of perturbation theory are overviewed. I discuss baryons with one finite mass
quark in the next-to-leading order and heavy quark pair production near the
threshold within NRQCD.

</DOC>
<DOC>
<DOCNO> 170000 </DOCNO>
The Entanglement of Formation for Isotropic States


  We give an explicit expression for the entanglement of formation for
isotropic density matrices in arbitrary dimensions in terms of the convex hull
of a simple function. For two qutrit isotropic states we determine the convex
hull and we have strong evidence for its exact form for arbitrary dimension.
Unlike for two qubits, the entanglement of formation for two qutrits or more is
found to be a nonanalytic function of the maximally entangled fraction in the
regime where the density matrix is entangled.

</DOC>
<DOC>
<DOCNO> 9067 </DOCNO>
Generalized model for dynamic percolation


  We study the dynamics of a carrier, which performs a biased motion under the
influence of an external field E, in an environment which is modeled by dynamic
percolation and created by hard-core particles. The particles move randomly on
a simple cubic lattice, constrained by hard-core exclusion, and they
spontaneously annihilate and re-appear at some prescribed rates. Using
decoupling of the third-order correlation functions into the product of the
pairwise carrier-particle correlations we determine the density profiles of the
"environment" particles, as seen from the stationary moving carrier, and
calculate its terminal velocity, V_c, as the function of the applied field and
other system parameters. We find that for sufficiently small driving forces the
force exerted on the carrier by the "environment" particles shows a
viscous-like behavior. An analog Stokes formula for such dynamic percolative
environments and the corresponding friction coefficient are derived. We show
that the density profile of the environment particles is strongly
inhomogeneous: In front of the stationary moving carrier the density is higher
than the average density, $\rho_s$, and approaches the average value as an
exponential function of the distance from the carrier. Past the carrier the
local density is lower than $\rho_s$ and the relaxation towards $\rho_s$ may
proceed differently depending on whether the particles number is or is not
explicitly conserved.

</DOC>
<DOC>
<DOCNO> 99842 </DOCNO>
Brane Solitons and Hypercomplex Structures


  The investigation of strings and M-theory involves the understanding of
various BPS solitons which in a certain approximation can be thought of as
solutions of ten- and eleven-dimensional supergravity theories. These solitons
have a brane or a intersecting brane interpretation, saturate a bound and are
associated with parallel spinors with respect to a connection of the spin
bundle of spacetime. A class of intersecting brane configurations is examined
and it is shown that the geometry of spacetime is hyper-K\"ahler with torsion.
A relation between these hyper-K\"ahler geometries with torsion and
quaternionic calibrations is also demonstrated.

</DOC>
<DOC>
<DOCNO> 150882 </DOCNO>
Remark on Quantum Nambu Bracket


  We give an explicit realization of quantum Nambu bracket via matrix of
multi-index, which reduces in the continunm limit to the classical Nambu
bracket.

</DOC>
<DOC>
<DOCNO> 10102 </DOCNO>
Thermal Fluctuations of Elastic Filaments with Spontaneous Curvature and


  We study the effects of thermal flucutations on thin elastic filaments with
spontaneous curvature and torsion. We derive analytical expressions for the
orientational correlation functions and for the persistence length of helices,
and find that this length varies non-monotonically with the strength of thermal
fluctuations. In the weak fluctuation regime, the persistence length of a
spontaneously twisted helix has three resonance peaks as a function of the
twist rate. In the limit of strong fluctuations, all memory of the helical
shape is lost.

</DOC>
<DOC>
<DOCNO> 169961 </DOCNO>
Optimization of entanglement witnesses


  An entanglement witness (EW) is an operator that allows to detect entangled
states. We give necessary and sufficient conditions for such operators to be
optimal, i.e. to detect entangled states in an optimal way. We show how to
optimize general EW, and then we particularize our results to the
non-decomposable ones; the latter are those that can detect positive partial
transpose entangled states (PPTES). We also present a method to systematically
construct and optimize this last class of operators based on the existence of
``edge'' PPTES, i.e. states that violate the range separability criterion
[Phys. Lett. A{\bf 232}, 333 (1997)] in an extreme manner. This method also
permits the systematic construction of non-decomposable positive maps (PM). Our
results lead to a novel sufficient condition for entanglement in terms of
non-decomposable EW and PM. Finally, we illustrate our results by constructing
optimal EW acting on $H=\C^2\otimes \C^4$. The corresponding PM constitute the
first examples of PM with minimal ``qubit'' domain, or - equivalently - minimal
hermitian conjugate codomain.

</DOC>
<DOC>
<DOCNO> 119653 </DOCNO>
Observations of the Soft Gamma-Ray early Afterglow emission from Two


  We present the results of observations of the soft gamma-ray early afterglows
with the energy above 100keV from two bright Gamma-ray bursts detected by the
PHEBUS instrument of the GRANAT orbital observatory. We show that the light
curves of GRB910402 and GRB920723 events present the afterglow emission with
fading fluxes. During our observations ~700s for these gamma-ray bursts the
afterglow emission was fading as the power law of time with indices equal to
-0.70+/-0.04 and -0.60+/-0.05 (at 1sigma confidence level). In both cases just
after the end of the GRB event we observed the energy spectrum of the afterglow
emissions which was softer than the energy spectrum of the main GRB events. The
average photon index of the main GRB event (in 100-800keV range) is equal to
\~1.5. In the beginning of the afterglow emission the energy spectra of both
events correspond to the much softer spectra with the photon index of ~2.5. We
found that the times of abrupt softening of the burst spectra correspond within
statistical errors to the moment when the afterglow emission begins to dominate
over GRB emission. We found that during the afterglow emission of GRB910402 the
statistically significant hardening of its spectra was observed. This is the
first observation of hardening of GRB afterglow emission. Analysis of GRB910402
and its afterglow showed that this GRB source emits during ~700s of our
observations in soft gamma-rays (100-500keV) only ~1.6% of its total energy
released during the main event. For the GRB920723 we found that in afterglow
during ~700s of our observations ~6% of the GRB total energy was released.

</DOC>
<DOC>
<DOCNO> 13025 </DOCNO>
Comment on "Magnetic Breakdown at High Fields: Semiclassical and Quantum


  We comment on the study of the spin-damping factor on the de Haas-van Alphen
(dHvA) discussed by Han et al. (Phys. Rev. Lett. 85, 1500 (2000)).

</DOC>
<DOC>
<DOCNO> 116758 </DOCNO>
Comment on Hydrogen-Antihydrogen collisions


  A comment on a recent paper by P. Froelich et. al., Phys. Rev. Lett., 84,
4577 (2000) on hydrogen-antihydrogen collisions and on matter-antimatter
reactions in general. The center of mass of a stable HHbar system has prochiral
character. It is not necessary to look for large scale anti-matter domains at
distances Mpc away or at the cosmological horizon.

</DOC>
<DOC>
<DOCNO> 119504 </DOCNO>
Observational Similarities and Potential Connections Between Luminous


  Luminous ultrasoft NLS1s and low-ionization BALQSOs share many properties,
and they both represent important extremes of the active galaxy phenomenon. We
briefly discuss their observational similarities as well as potential physical
connections between them, concentrating on the X-ray point of view. We present
several ways by which potential connections might be further tested.

</DOC>
<DOC>
<DOCNO> 119956 </DOCNO>
Signs of the cusps in binary lenses


  The cusps of the caustics of any gravitational lens model can be classified
into positive and negative ones. This distinction lies on the parity of the
images involved in the creation/destruction of pairs occurring when a source
crosses a caustic in a cusp. In this paper, we generalize the former definition
of the sign of the cusps. Then we apply it to the binary lens. We demonstrate
that the cusps on the axis joining the two lenses are positive while the others
are negative. To achieve our objective, we combine catastrophe theory, usually
employed in the derivation of the properties of caustics, with perturbative
methods, in order to simplify calculations and get readable results. Extensions
to multiple lenses are also considered.

</DOC>
<DOC>
<DOCNO> 101003 </DOCNO>
On the commuting holomorphic endomorphisms of P^k


  Let f_1, f_2 be holomorphic endomorphisms of P^k, of degrees d_1\geq 2,
d_2\geq 2. Assume that f_1\circ f_2=f_2\circ f_1 and that d_1^{n_1}\not
=d_2^{n_2} for all integers n_1, n_2. We then show that f_j are critically
finite. Moreover there is an orbifold (P^k,n) such that f_1, f_2 are coverings
of (P^k,n). In the P^2 case we give the list of commuting pairs satisfying the
above conditions.

</DOC>
<DOC>
<DOCNO> 119611 </DOCNO>
Event reconstruction in high resolution Compton telescopes


  The development of germanium Compton telescopes for nuclear gamma-ray
astrophysics (~0.2-20 MeV) requires new event reconstruction techniques to
accurately determine the initial direction and energy of photon events, as well
as to consistently reject background events. This paper describes techniques
for event reconstruction, accounting for realistic instrument/detector
performance and uncertainties. An especially important technique is Compton
Kinematic Discrimination, which allows proper interaction ordering and
background rejection with high probabilities. The use of these techniques are
crucial for the realistic evaluation of the performance and sensitivity of any
germanium Compton telescope configuration.

</DOC>
<DOC>
<DOCNO> 151002 </DOCNO>
Dyons with axial symmetry


  We construct axially symmetric dyons in SU(2) Yang-Mills-Higgs theory. In the
Prasad-Sommerfield limit, they are obtained via scaling relations from axially
symmetric multimonopole solutions. For finite Higgs self-coupling they are
constructed numerically.

</DOC>
<DOC>
<DOCNO> 80974 </DOCNO>
Flop Transitions in Cuprate and Color Superconductors: From SO(5) to


  The phase diagrams of cuprate superconductors and of QCD at non-zero baryon
chemical potential are qualitatively similar. The Neel phase of the cuprates
corresponds to the chirally broken phase of QCD, and the high-temperature
superconducting phase corresponds to the color superconducting phase. In the
SO(5) theory for the cuprates the $SO(3)_s$ spin rotational symmetry and the
$U(1)_{em}$ gauge symmetry of electromagnetism are dynamically unified. This
suggests that the $SU(2)_L \otimes SU(2)_R \otimes U(1)_B$ chiral symmetry of
QCD and the $SU(3)_c$ color gauge symmetry may get unified to SO(10). Dynamical
enhancement of symmetry from $SO(2)_s \otimes \Z(2)$ to $SO(3)_s$ is known to
occur in anisotropic antiferromagnets. In these systems the staggered
magnetization flops from an easy 3-axis into the 12-plane at a critical value
of the external magnetic field. Similarly, the phase transitions in the SO(5)
and SO(10) models are flop transitions of a ``superspin''. Despite this fact, a
renormalization group flow analysis in $4-\epsilon$ dimensions indicates that a
point with full SO(5) or SO(10) symmetry exists neither in the cuprates nor in
QCD.

</DOC>
<DOC>
<DOCNO> 122341 </DOCNO>
HI gas disks in elliptical galaxies


  We discuss a class of low-luminosity E/S0 galaxies which have both HI disks
and (in contrast to more luminous E/S0s with HI) ongoing star formation. We
suggest that such objects are common, but that only a few are known at present
because optical magnitude-limited galaxy catalogues are biased against them.
The HI Parkes All-Sky Survey (HIPASS) should eventually detect many more. We
suggest that `boxy' and `disky' ellipticals are distinct not only in their
structure and kinematics, but in their star-formation history.

</DOC>
<DOC>
<DOCNO> 119859 </DOCNO>
Strange hadronic stellar matter within the Brueckner-Bethe-Goldstone


  In the framework of the non-relativistic Brueckner-Bethe-Goldstone theory, we
derive a microscopic equation of state for asymmetric and $\beta$-stable matter
containing $\Sigma^-$ and $\Lambda$ hyperons. We mainly study the effects of
three-body forces (TBFs) among nucleons on the hyperon formation and the
equation of state (EoS). We find that, when TBFs are included, the stellar core
is almost equally populated by nucleons and hyperons. The resulting EoS, which
turns out to be extremely soft, has been used in order to calculate the static
structure of neutron stars. We obtain a value of the maximum mass of 1.26 solar
masses (1 solar mass $M_o \simeq 1.99 \cdot 10^{33} g$). Stellar rotations
increase this value by about 12%.

</DOC>
<DOC>
<DOCNO> 122446 </DOCNO>
MACHO Project Limits on Black Hole Dark Matter in the 1-30 Solar Mass


  We report on a search for long duration microlensing events towards the Large
Magellanic Cloud. We find none, and therefore put limits on the contribution of
high mass objects to the Galactic dark matter. At 95% confidence level we
exclude objects in the mass range 0.3 solar masses to 30.0 solar masses from
contributing more than 4 times 10^11 solar masses to the Galactic halo.
Combined with earlier results, this means that objects with masses under 30
solar masses cannot make up the entire dark matter halo if the halo is of
typical size. For a typical dark halo, objects with masses under 10 solar
masses contribute less than 40% of the dark matter.

</DOC>
<DOC>
<DOCNO> 10205 </DOCNO>
Bluff your way in the second law of thermodynamics


  The aim of this article is to analyze the relation between the second law of
thermodynamics and the so-called arrow of time. For this purpose, a number of
different aspects in this arrow of time are distinguished, in particular those
of time-(a)symmetry and of (ir)reversibility. Next I review versions of the
second law in the work of Carnot, Clausius, Kelvin, Planck, Gibbs,
Carath\'eodory and Lieb and Yngvason, and investigate their connection with
these aspects of the arrow of time.
  It is shown that this connection varies a great deal along with these
formulations of the second law. According to the famous formulation by Planck,
the second law expresses the irreversibility of natural processes. But in many
other formulations irreversibility or even time-asymmetry plays no role.
  I therefore argue for the view that the second law has nothing to do with the
arrow of time.
  Key words: thermodynamics, second law, irreversibility, time-asymmetry, arrow
of time.

</DOC>
<DOC>
<DOCNO> 68792 </DOCNO>
Probing Left-handed Slepton Flavor Mixing at Future Lepton Colliders


  It has been argued in the literature that the search for the slepton
oscillation phenomenon can be a powerful probe of intergenerational mixing
between sleptons, once sleptons are found at future colliders. In this article
we estimate possible reach of future lepton colliders in probing left-handed
slepton flavor mixing, especially mixing between the first and third
generations, on which constraints imposed by other processes like $\tau \to e
\gamma$ are very weak. $e^+e^-$ collider is suitable for this purpose, since it
can produce, if kinematically allowed, sleptons of the first generation via
t-channel, in addition to s-channel. Utilizing $e^+e^- \to \tau e + 4jets + \E$
signal at $e^+e^-$ linear collider with integrated luminosity L=50 fb^{-1}(500
fb^{-1}) it may be possible to reach mixing angle $\sin 2\theta_{\tilde{\nu}}
\gtrsim 0.06 (0.04)$ and mass difference $\Delta m_{\tilde{\nu}} \gtrsim 0.07
(0.04)$ GeV for sneutrinos in the first and third generations at the
statistical significance of 5 \sigma.

</DOC>
<DOC>
<DOCNO> 102892 </DOCNO>
An arithmetic function of two variables


  The arithmetic function of two variables is defined. Some properties of the
function are given along with the formula that is an analog of the so-called
Mobius' inversion formula. A heuristic statement is suggested.

</DOC>
<DOC>
<DOCNO> 9379 </DOCNO>
Addendum on rotational properties of confined bosons: time-inversion


  In this addendum we introduce the concept of time-inversion referencing. This
is an extension of hypertext allowing authors to cite papers that where not yet
published (or even not yet written) when they publish a manuscript. We are
convinced that this concept will prove very useful especially when adjustments
to the so-called intellectual property rights have to be made. We apply the
concept to our paper on rotational properties of trapped bosons.

</DOC>
<DOC>
<DOCNO> 69019 </DOCNO>
Light-front vacuum and instantons in two dimensions


  We review several aspects of Yang-Mills theory (YMT) in two dimensions,
related to its perturbative and topological properties. Consistency between
light-front and equal-time formulations is thoroughly discussed.

</DOC>
<DOC>
<DOCNO> 116752 </DOCNO>
The shock-acoustic waves generated by earthquakes


  We investigate the form and dynamics of shock-acoustic waves generated by
earthquakes. We use the method for detecting and locating the sources of
ionospheric impulsive disturbances, based on using data from a global network
of receivers of the GPS navigation system and requiring no a priori information
about the place and time of associated effects. The practical implementation of
the method is illustrated by a case study of earthquake effects in Turkey
(August 17, and November 12, 1999), in Southern Sumatera (June 4, 2000), and
off the coast of Central America (January 13, 2001). It was found that in all
instances the time period of the ionospheric response is 180-390 s, and the
amplitude exceeds by a factor of two as a minimum the standard deviation of
background fluctuations in total electron content in this range of periods
under quiet and moderate geomagnetic conditions. The elevation of the wave
vector varies through a range of 20-44 degree, and the phase velocity
(1100-1300 m/s) approaches the sound velocity at the heights of the ionospheric
F-region maximum. The calculated (by neglecting refraction corrections)
location of the source roughly corresponds to the earthquake epicenter. Our
data are consistent with the present views that shock-acoustic waves are caused
by a piston-like movement of the Earth surface in the zone of an earthquake
epicenter.

</DOC>
<DOC>
<DOCNO> 84291 </DOCNO>
(^-L_n,g)-spaces. Length of a vector field and the angle between two


  The notions of length of a vector field and cosine of the angle between two
vector fields over a differentiable manifold with contravariant and covariant
affine connections and metrics are introduced and considered. The change of the
length of a vector field and of the angle between two vector fields along a
contravariant vector field are found. The introduced notions are necessary for
investigations of different types of transports over a manifold of the above
mentioned type.

</DOC>
<DOC>
<DOCNO> 101089 </DOCNO>
Heat asymptotics with spectral boundary conditions II


  Let $P$ be an operator of Dirac type on a compact Riemannian manifold with
smooth boundary. We impose spectral boundary conditions and study the
asymptotics of the heat trace of the associated operator of Laplace type.

</DOC>
<DOC>
<DOCNO> 121100 </DOCNO>
Long-term optical and X-ray observations of the old novae DI Lacertae


  We present an analysis of ground-based optical photometry and spectroscopy,
and Rossi X-ray Timing Explorer X-ray observations of the old novae DI Lacertae
and V841 Ophiuchi. Our optical photometry data (obtained with the automated
photometry telescope RoboScope) comprise an almost decade-long light curve for
each star, while the contemporaneous spectroscopy and X-ray observations
repeatedly sampled each nova during separate intervals of ~45-55 d in length.
The long-term optical light curves of both novae reveal quasiperiodic
variability on typical time scales of ~30-50 d with amplitudes of dV ~ 0.4-0.8
mag. V841 Oph also displays a long-term, sinusoidal modulation of its optical
light on a time scale of 3.5-5 yr. The optical spectra of these novae display
quite different characteristics from each other, with DI Lac showing narrow
Balmer emission cores situated in broad absorption troughs while V841 Oph
exhibits strong single-peaked Balmer, He I and He II emission lines. We find
little change between spectra obtained during different optical brightness
states. The X-ray count rates for both novae were very low (< ~1.5 ct/s) and
there was no reliable correlation between X-ray and optical brightness. The
combined X-ray spectrum of DI Lac is best fit by a bremsstrahlung emission
model (with kT ~ 4 keV and N_H < 1.8x10^22 cm^-3); the X-ray spectrum of V841
Oph is too weak to allow model fitting. We discuss the possible origin of
variability in these old novae in terms of magnetic activity on the secondary
star, dwarf nova type disk instabilities, and the ``hibernation'' scenario for
cataclysmic variable stars.

</DOC>
<DOC>
<DOCNO> 70127 </DOCNO>
Thermal Equilibration of Brane-Worlds


  We analyze the thermodynamical properties of brane-worlds, with a focus on
the second model of Randall and Sundrum. We point out that during an
inflationary phase on the brane, black holes will tend to be thermally
nucleated in the bulk. This leads us to ask the question: Can the black hole -
brane-world system evolve towards a configuration of thermal equilibrium? To
answer this, we generalize the second Randall-Sundrum scenario to allow for
non-static bulk regions on each side of the brane-world. Explicitly, we take
the bulk to be a {\it Vaidya-AdS} metric, which describes the gravitational
collapse of a spherically symmetric null dust fluid in Anti-de Sitter
spacetime. Using the background subtraction technique to calculate the
Euclidean action, we argue that at late times a sufficiently large black hole
will relax to a point of thermal equilibrium with the brane-world environment.
These results have interesting implications for early-universe cosmology.

</DOC>
<DOC>
<DOCNO> 10940 </DOCNO>
A nature of low-temperature resistivity minimum in ceramic manganites


  Measurements of magnetoresistance and magnetization were carried out on
ceramic samples of La_{0.5}Pb_{0.5}MnO_{3} and La_{0.5}Pb_{0.5}MnO_{3},
containing 10 at. % Ag in a dispersed form. The results obtained for the
resistivity at zero applied magnetic field exhibit a shallow minimum at
temperatures T about 25 K - 30 K, which shifts towards lower temperatures upon
applying magnetic field and disappears at a certain (rather low) field. Also
the resistivity at helium temperature decreases upon applying magnetic fields.
It is shown that the model of spin-dependent carrier tunneling between
antiferromagnetically coupled grains may account for the results observed.

</DOC>
<DOC>
<DOCNO> 9207 </DOCNO>
Thermal quasi-equilibrium states across Landau horizons in the effective


  We give an account of the physical behaviour of a quasiparticle horizon due
to non-Lorentz invariant modifications of the effective space-time experienced
by the quasiparticles (``matter'') for high momenta. By introducing a
``relativistic'' conserved energy-momentum tensor, we derive quasi-equilibrium
states of the fluid across the ``Landau'' quasiparticle horizon at temperatures
well above the quantum Hawking temperature. Nonlinear dispersion of the
quasiparticle energy spectrum is instrumental for quasiparticle communication
and exchange across the horizon. It is responsible for the establishment of the
local thermal equilibrium across the horizon with the Tolman temperature being
inhomogeneous behind the horizon. The inhomogeneity causes relaxation of the
quasi-equilibrium states due to scattering of thermal quasiparticles, which
finally leads to a shrinking black hole horizon. This process serves as the
classical thermal counterpart of the quantum effect of Hawking radiation and
will allow for an observation of the properties of the horizon at temperatures
well above the Hawking temperature. We discuss the thermal entropy related to
the horizon. We find that only the first nonlinear correction to the energy
spectrum is important for the thermal properties of the horizon. They are fully
determined by an energy of order $E_{\rm Planck}(T/E_{\rm Planck})^{1/3}$,
which is well below the Planck energy scale $E_{\rm Planck}$, so that Planck
scale physics is not involved in determining thermal quantities related to the
horizon.

</DOC>
<DOC>
<DOCNO> 84708 </DOCNO>
Huge Violations of Bekenstein's Entropy Bound


  Bekenstein's conjectured entropy bound for a system of linear size R and
energy E, S < 2 pi E R, can be violated by an arbitrarily large factor, among
other ways, by a scalar field having a symmetric potential allowing domain
walls, and by the electromagnetic field modes between an arbitrarily large
number of conducting plates.

</DOC>
<DOC>
<DOCNO> 178642 </DOCNO>
Collective Quadrupole Excitations in Transitional Nuclei


  The generalized Bohr Hamiltonian was used to describe the low-lying
collective excitations in even-even isotopes of Ru, Pd, Te, Ba and Nd. The
Strutinsky collective potential and cranking inertial functions were obtained
using the Nilsson potential. The effect of coupling with the pairing vibrations
is taken into account approximately when determining the inertial functions.
The calculation does not contain any free parameter.

</DOC>
<DOC>
<DOCNO> 8020 </DOCNO>
Scattering of positronium by H, He, Ne, and Ar


  The low-energy scattering of ortho positronium (Ps) by H, He, Ne, and Ar
atoms has been investigated in the coupled-channel framework by using a
recently proposed time-reversal-symmetric nonlocal electron-exchange model
potential with a single parameter $C$. For H and He we use a three-Ps-state
coupled-channel model and for Ar and Ne we use a static-exchange model. The
sensitivity of the results is studied with respect to the parameter $C$.
Present low-energy cross sections for He, Ne and Ar are in good agreement with
experiment.

</DOC>
<DOC>
<DOCNO> 117385 </DOCNO>
Observational Tests for the Cosmological Principle and World Models


  We review observational tests for the homogeneity of the Universe on large
scales. Redshift and peculiar velocity surveys, radio sources, the X-Ray
Background, the Lyman-$\alpha$ forest and the Cosmic Microwave Background are
used to set constraints on inhomogeneous models and in particular on
fractal-like models.
  Assuming the Cosmological Principle and the FRW metric, we estimate
cosmological parameters by joint analysis of peculiar velocities, the CMB,
cluster abundance, IRAS and Supernovae.
  Under certain assumptions the best fit density parameter is Omega_m = 1 -
lambda \approx 0.4 .
  We present a new method for joint estimation by combining different data sets
in a Bayesian way, and utilising `Hyper-Parameters'.

</DOC>
<DOC>
<DOCNO> 9463 </DOCNO>
Small Bipolarons in the 2-dimensional Holstein-Hubbard Model. II Quantum


  We study the effective mass of the bipolarons and essentially the possibility
to get both light and strongly bound bipolarons in the Holstein-Hubbard model
and some variations in the vicinity of the adiabatic limit. Several approaches
to investigate the quantum mobility of polarons and bipolarons are proposed for
this model. It is found that the bipolaron mass generally remains very large
except in the vicinity of the triple point of the phase diagram, where the
bipolarons have several degenerate configurations at the adiabatic limit
(single site (S0), two sites (S1) and quadrisinglet (QS)), while the polarons
are much lighter. This degeneracy reduces the bipolaron mass significantly. The
triple point of the phase diagram is washed out by the lattice quantum
fluctuations which thus suppress the light bipolarons. We show that some model
variations, for example a phonon dispersion may increase the stability of the
(QS) bipolaron against the quantum lattice fluctuations. The triple point of
the phase diagram may be stable to quantum lattice fluctuations and a very
sharp mass reduction may occur, leading to bipolaron masses of the order of 100
bare electronic mass for realistic parameters. Thus such very light bipolarons
could condense as a superconducting state at relatively high temperature when
their interactions are not too large, that is, their density is small enough.
This effect might be relevant for understanding the origin of the high Tc
superconductivity of doped cuprates far enough from half filling.

</DOC>
<DOC>
<DOCNO> 102554 </DOCNO>
Multiderivations of Coxeter arrangements


  Let $V$ be an $\ell$-dimensional Euclidean space. Let $G \subset O(V)$ be a
finite irreducible orthogonal reflection group. Let ${\cal A}$ be the
corresponding Coxeter arrangement. Let $S$ be the algebra of polynomial
functions on $V.$ For $H \in {\cal A}$ choose $\alpha_H \in V^*$ such that $H =
{\rm ker}(\alpha_H).$ For each nonnegative integer $m$, define the derivation
module $\sD^{(m)}({\cal A}) = \{\theta \in {\rm Der}_S | \theta(\alpha_H) \in S
\alpha^m_H\}$. The module is known to be a free $S$-module of rank $\ell$ by K.
Saito (1975) for $m=1$ and L. Solomon-H. Terao (1998) for $m=2$. The main
result of this paper is that this is the case for all $m$. Moreover we
explicitly construct a basis for $\sD^{(m)} (\cal A)$. Their degrees are all
equal to $mh/2$ (when $m$ is even) or are equal to $((m-1)h/2) + m_i (1 \leq i
\leq \ell)$ (when $m$ is odd). Here $m_1 \leq ... \leq m_{\ell}$ are the
exponents of $G$ and $h= m_{\ell} + 1$ is the Coxeter number. The construction
heavily uses the primitive derivation $D$ which plays a central role in the
theory of flat generators by K. Saito (or equivalently the Frobenius manifold
structure for the orbit space of $G$.) Some new results concerning the
primitive derivation $D$ are obtained in the course of proof of the main
result.

</DOC>
<DOC>
<DOCNO> 117511 </DOCNO>
Clustering in the X-ray Universe


  In this paper we discuss various possibilities of using X-ray observations to
gain information about the large-scale structure of the Universe. After
reviewing briefly the current status of these investigations we explore
different ways of making progress in this field, using deep surveys, large area
surveys and X-ray background observations.

</DOC>
<DOC>
<DOCNO> 178674 </DOCNO>
Are there universal freeze-out parameters for central 158AGeV Pb+Pb


  Earlier attempts to extract parameters of kinetic freeze-out in Pb+Pb
collisions at 158$A$GeV are critically reviewed. Many of these analyses have
used approximations which have significant impact on the extracted parameters.
Simple estimates are obtained which attempt to avoid the most critical
approximations. It is pointed out that constraints based on pion interferometry
are less reliable than those from momentum spectra. A universal set of
freeze-out parameters from transverse mass spectra would require T > 135 MeV
and <beta> < 0.35.

</DOC>
<DOC>
<DOCNO> 120586 </DOCNO>
A Sensitive Search for Methane in the Infrared Spectrum of Tau Bootis


  We have searched for a methane signature in the infrared spectrum of tau
Bootis, produced by the planetary companion. The observations comprise 598
low-noise, high resolution spectra near 3.28 microns, which we analyze by
cross-correlating with a modeled planetary spectrum based on the work of
Burrows and Sharp (1999), and Sudarsky et al. (2000). The 3-sigma random noise
level of our analysis is 0.00006 stellar continuum flux units, and the
confusion noise limit - measuring the resemblence of a cross-correlation
feature to the spectrum of methane - is 0.00025.
  We find a significant cross-correlation amplitude of 0.00033 continuum units
at a velocity near that of the star. This is likely due to methane from a
low-mass companion in a long-period orbit. Fischer, Butler and Marcy (2000)
report a long-term velocity drift indicative of such a companion. But the
system is known to be a visual binary with an eccentric orbit, and is rapidly
approaching periastron. Whether the visual companion can account for our
observations and the Fischer et al. velocity drift depends on knowing the orbit
more precisely. The stability of planetary orbits in this system also depends
crucially on the properties of the binary orbit. A second cross-correlation
feature, weaker and much more diffuse, has intensity amplitude 0.0002 continuum
units and occurs at a velocity amplitude of 71 +/-10 km/sec, in agreement with
the orbit claimed for the planet by Cameron et al. (1999). Like the first
feature, it has passed several tests designed to reject systematic errors. We
discuss the possibility that this second feature is due to the planet.

</DOC>
<DOC>
<DOCNO> 84512 </DOCNO>
Photon frequency conversion induced by gravitational radiation


  We consider propagation of gravitational radiation in a magnetized
multicomponent plasma. It is shown that large density perturbations can be
generated, even for small deviations from flat space, provided the cyclotron
frequency is much larger than the plasma frequency. Furthermore, the induced
density gradients can generate frequency conversion of electromagnetic
radiation, which may give rise to indirect observational effect of the
gravitational waves.

</DOC>
<DOC>
<DOCNO> 101653 </DOCNO>
Note on Extended Coherent Operators and Some Basic Properties


  This is a continuation of the paper (quant-ph/0009012).
  In this letter we extend coherent operators and study some basic properties
(the disentangling formula, resolution of unity, commutation relation, etc). We
also propose a perspective of our work.

</DOC>
<DOC>
<DOCNO> 151648 </DOCNO>
Noncommutative Superstring Worldsheet


  In this paper we consider the worldsheet of superstring as a noncommutative
space. Some additional terms can be added to the superstring action, that for
ordinary worldsheet are zero. Expansion of this extended action up to the first
order of the noncommutativity parameter of the string worldsheet, leads to the
new supersymmetric action for string. For the closed superstring, we obtain the
boundary state that describes a brane. From the open string point of view, the
new boundary conditions on the worldsheet bosons, generalize the
noncommutativity of spacetime. Finally, we suggest some definitions for the
noncommutativity parameter of the superstring worldsheet.

</DOC>
<DOC>
<DOCNO> 117978 </DOCNO>
Comptonization, reflection and noise in black hole binaries


  Based on the analysis of a large sample of RXTE/PCA observations of several
black hole binaries in the low spectral state we show that a correlation exists
between the spectral parameters and characteristic noise frequency. In
particular, the amplitude of reflection increases and the slope of Comptonized
radiation steepens as the noise frequency increases. We consider possible
implications of these results on the accretion flow models and discuss a
possible observational test aimed to discriminate between different geometries
of the accretion flow.

</DOC>
<DOC>
<DOCNO> 118559 </DOCNO>
The ROSAT Brightest Cluster Sample (BCS) - IV. The extended sample


  We present a low-flux extension of the X-ray selected ROSAT Brightest Cluster
Sample (BCS) published in Paper I of this series. Like the original BCS and
employing an identical selection procedure, the BCS extension is compiled from
ROSAT All-Sky Survey (RASS) data in the northern hemisphere (dec > 0 deg) and
at high Galactic latitudes (|b| > 20 deg). It comprises 100 X-ray selected
clusters of galaxies with measured redshifts z < 0.3 (as well as seven more at
z > 0.3) and total fluxes between 2.8 x 10-12 erg cm-2 s-1 and 4.4 x 10-12 erg
cm-2 s-1 in the 0.1-2.4 keV band (the latter value being the flux limit of the
original BCS). The extension can be combined with the main sample published in
1998 to form the homogeneously selected extended BCS (eBCS), the largest and
statistically best understood cluster sample to emerge from the ROSAT All-Sky
Survey to date.
  The nominal completeness of the combined sample (defined with respect to a
power law fit to the bright end of the BCS log N-log S distribution) is
relatively low at 75 per cent (compared to 90 per cent for the high-flux sample
of Paper I). However, just as for the original BCS, this incompleteness can be
accurately quantified, and thus statistically corrected for, as a function of
X-ray luminosity and redshift.
  In addition to its importance for improved statistical studies of the
properties of clusters in the local Universe, the low-flux extension of the BCS
is also intended to serve as a finding list for X-ray bright clusters in the
northern hemisphere which we hope will prove useful in the preparation of
cluster observations with the next generation of X-ray telescopes such as
Chandra or XMM-Newton.

</DOC>
<DOC>
<DOCNO> 7991 </DOCNO>
Antiferromagnetic Alignment and Relaxation Rate of Gd Spins in the High


  The complex surface impedance of a number of GdBa$_2$Cu$_3$O$_{7-\delta}$
single crystals has been measured at 10, 15 and 21 GHz using a cavity
perturbation technique. At low temperatures a marked increase in the effective
penetration depth and surface resistance is observed associated with the
paramagnetic and antiferromagnetic alignment of the Gd spins. The effective
penetration depth has a sharp change in slope at the N\'eel temperature, $T_N$,
and the surface resistance peaks at a frequency dependent temperature below 3K.
The observed temperature and frequency dependence can be described by a model
which assumes a negligibly small interaction between the Gd spins and the
electrons in the superconducting state, with a frequency dependent magnetic
susceptibility and a Gd spin relaxation time $\tau_s $ being a strong function
of temperature. Above $T_N$, $\tau_s$ has a component varying as $1 / (T -
T_N)$, while below $T_N$ it increases $\sim T^{-5}$.

</DOC>
<DOC>
<DOCNO> 9939 </DOCNO>
Current-spin-density functional study of persistent currents in quantum


  We present a numerical study of persistent currents in quantum rings using
current spin density functional theory (CSDFT). This formalism allows for a
systematic study of the joint effects of both spin, interactions and impurities
for realistic systems. It is illustrated that CSDFT is suitable for describing
the physical effects related to Aharonov-Bohm phases by comparing energy
spectra of impurity-free rings to existing exact diagonalization and
experimental results. Further, we examine the effects of a symmetry-breaking
impurity potential on the density and current characteristics of the system and
propose that narrowing the confining potential at fixed impurity potential will
suppress the persistent current in a characteristic way.

</DOC>
<DOC>
<DOCNO> 100434 </DOCNO>
Fusion bases for affine Lie algebras


  Fusion coefficients for affine Lie algebras are fixed by the corresponding
tensor-product coefficients and a set of threshold levels. It is shown how the
information concerning the threshold level is coded in the fusion basis, which
is a set of inequalities that completely describes the fusion coefficients. The
construction of the su(2) fusion basis is presented in detail.

</DOC>
<DOC>
<DOCNO> 10613 </DOCNO>
A simple theory for high $\Delta / T_{c}$ ratio in d-wave


  We investigate a simple explanation for the high maximum gap to $T_{c}$ ratio
found experimentally in high $T_{c}$ compounds. We ascribe this observation to
the lowering of $T_{c}$ by boson scattering of electrons between parts of the
Fermi surface with opposite sign for the order parameter. We study the simplest
possible model within this picture. Our quantitative results show that we can
account for experiment for a rather small value of the coupling constant, all
the other ingredients of our model being already known to exist in these
compounds. A striking implication of this theory is the fairly high value of
the critical temperature in the absence of boson scattering.

</DOC>
<DOC>
<DOCNO> 8573 </DOCNO>
Nonlinear viscosity and velocity distribution function in a simple


  A compressible flow characterized by a velocity field $u_x(x,t)=ax/(1+at)$ is
analyzed by means of the Boltzmann equation and the Bhatnagar-Gross-Krook
kinetic model. The sign of the control parameter (the longitudinal deformation
rate $a$) distinguishes between an expansion ($a>0$) and a condensation ($a<0$)
phenomenon. The temperature is a decreasing function of time in the former
case, while it is an increasing function in the latter. The non-Newtonian
behavior of the gas is described by a dimensionless nonlinear viscosity
$\eta^*(a^*)$, that depends on the dimensionless longitudinal rate $a^*$. The
Chapman-Enskog expansion of $\eta^*$ in powers of $a^*$ is seen to be only
asymptotic (except in the case of Maxwell molecules). The velocity distribution
function is also studied. At any value of $a^*$, it exhibits an algebraic
high-velocity tail that is responsible for the divergence of velocity moments.
For sufficiently negative $a^*$, moments of degree four and higher may diverge,
while for positive $a^*$ the divergence occurs in moments of degree equal to or
larger than eight.

</DOC>
<DOC>
<DOCNO> 71183 </DOCNO>
Analyticity and Quark-Gluon Structure of Hadrons


  The amplitudes of hadron-hadron forward elastic scattering at high energy a
re investigated on the basis of analiticity and crossing-symmetry which is
valid in QCD. The universal uniformizing variable for them is proposed and the
formulae for crossing-even and crossing-odd amplitudes are derived. The same
parameters in these formulae determine the real and imaginary (total cross
sections) parts of the amplitudes. The analysis of the parameters determined
from experimental data clearly points to the quark-gluon stracture of hadrons.
The total cross sections for hyperon-proton scattering are predicted. They are
consistent with experimental data and, in particular, with the new
SELEX-collaboration measurement $\sigma_{tot}(\Sigma^{-} p)$.

</DOC>
<DOC>
<DOCNO> 85134 </DOCNO>
Quantum metric fluctuations and Hawking radiation


  In this Letter we study the gravitational interactions between outgoing
configurations giving rise to Hawking radiation and in-falling configurations.
When the latter are in their ground state, the near horizon interactions lead
to collective effects which express themselves as metric fluctuations and which
induce dissipation, as in Brownian motion. This dissipation prevents the
appearance of trans-Planckian frequencies and leads to a description of Hawking
radiation which is very similar to that obtained from sound propagation in
condensed matter models.

</DOC>
<DOC>
<DOCNO> 101135 </DOCNO>
Systems of linear ordinary differential equations with bounded


  An elementary example shows that the number of zeroes of a component of a
solution of a system of linear ordinary differential equations cannot be
estimated through the norm of coefficients of the system alone.

</DOC>
<DOC>
<DOCNO> 170729 </DOCNO>
Communication of Spin Directions with Product States and Finite


  Total spin eigenstates can be used to intrinsically encode a direction, which
can later be decoded by means of a quantum measurement. We study the optimal
strategy that can be adopted if, as is likely in practical applications, only
product states of $N$-spins are available. We obtain the asymptotic behaviour
of the average fidelity which provides a proof that the optimal states must be
entangled. We also give a prescription for constructing finite measurements for
general encoding eigenstates.

</DOC>
<DOC>
<DOCNO> 100623 </DOCNO>
On a Vanishing Theorem of Kontsevich


  This paper has been withdrawn by the authors, due a crucial mistake in Lemma
2

</DOC>
<DOC>
<DOCNO> 12026 </DOCNO>
Charge induced energy fluctuations in thin organic films: effect on


  Effect of static charges on charge carrier transport in disordered organic
materials is considered. Long range nature of Coulomb interaction requires to
take into consideration a finite thickness of the transport layer. Presence of
conducting electrodes significantly modifies properties of organic medium,
removes a long range Coulomb divergence, and makes it possible to calculate in
finite form statistical properties of organic medium (with nonzero total charge
density), relevant for transport characteristics. A special attention is paid
to the particular case of charge induced disorder - a disorder originated from
the surface charge located at the rough surface of electrode. We present also a
generalization of 1D model of charge carrier transport to the case of
inhomogeneous energetic disorder that realizes in for charge induced disorder.

</DOC>
<DOC>
<DOCNO> 123185 </DOCNO>
The consequences of ram pressure stripping on the Virgo cluster spiral


  New H-alpha Fabry-Perot interferometer observations of the Virgo cluster
spiral galaxy NGC 4522 are presented. A velocity field up to a radius of 60''
was obtained. The observed rotation curve is symmetric. It is not perturbed in
the inner disk. For radii >50'' it shows a solid body rotation. We compare
these data with a numerical model which includes the effects of ram pressure
stripping. The model can reproduce the main characteristics of the H-alpha
emission distribution and velocity field. We therefore conclude that the
stripping event which caused the HI deficiency and the distorted H-alpha
distribution and velocity field has been due to ram pressure. The closest
passage of the galaxy to the cluster center is estimated to be approx. 6.5 10^8
yr ago. The observed recent star formation is due to the re-accretion of gas
clouds which were accelerated to velocities below the escape velocity during
the stripping event. Furthermore, the gas which is located at radii >60'' is
part of an asymmetric expanding ring of gas clouds. A substantial part of these
clouds is located above the disk plane. We predict the HI gas distribution and
velocity field as it would be observed by deep 21 cm observations.

</DOC>
<DOC>
<DOCNO> 69797 </DOCNO>
Kinematic Constraints to the Key Inflationary Observables


  The observables $T/S$ and $n-1$ are key to testing and understanding
inflation. ($T$, $S$, and $n-1$ respectively quantify the gravity-wave and
density-perturbation contributions to CMB anisotropy and the deviation of the
density perturbations from the scale-invariant form.) Absent a standard model,
there is no definite prediction for, or relation between, $T/S$ and $n-1$. By
reformulating the equations governing inflation we show that models generally
predict $T/S \approx -5(n-1)$ or 0, and in particular, if $n>0.85$, $T/S$ is
expected to be $>10^{-3}$.

</DOC>
<DOC>
<DOCNO> 99700 </DOCNO>
Absolutely singular dynamical foliations


  We show that for the C^1-open set of partially hyperbolic diffeomorphisms
constructed in (M. Shub and A. Wilkinson, "Pathological foliations and
removable zero exponents," Invent. math. 139 (2000) 3, 495-508), Lebesgue
measure on the 3-torus decomposes as atomic measure along the leaves of the
central foliation.

</DOC>
<DOC>
<DOCNO> 10595 </DOCNO>
Tsallis Statistics: Averages and a Physical Interpretation of the


  Tsallis has proposed a generalisation of the standard entropy, which has
since been applied to a variety of physical systems. In the canonical ensemble
approach that is mostly used, average energy is given by an unnromalised, or
normalised, $q$-expectation value. A Lagrange multiplier $\beta$ enforces the
energy constraint whose physical interpretation, however, is lacking. Here, we
use a microcanonical ensemble approach and find that consistency requires that
only normalised $q$-expectation values are to be used. We then present a
physical interpretation of $\beta$, relating it to a physical temperature. We
derive this interpretation by a different method also.

</DOC>
<DOC>
<DOCNO> 117528 </DOCNO>
A ROSAT HRI survey of bright nearby galaxies


  We use the extensive public archive of ROSAT High Resolution Imager (HRI)
observations to carry out a statistical investigation of the X-ray properties
of nearby galaxies. Specifically we focus on the sample of 486 bright (B_T <
12.5) northern galaxies studied by Ho, Filippenko and Sargent (HFS) in the
context of their exploration of the optical spectroscopic properties of nearby
galactic nuclei. Over 20% of HFS galaxies are encompassed in ROSAT HRI fields
of reasonable (> 10ks) exposure. The X-ray sources detected within the optical
extent of each galaxy are categorised as either nuclear or non-nuclear
depending on whether the source is positioned within or outside of a 25
arcsecond radius circle centred on the optical nucleus. A nuclear X-ray source
is detected in over 70% of the galaxies harbouring either a Seyfert or LINER
nucleus compared to a detection rate of only ~40% in less active systems. The
correlation of the H alpha luminosity with nuclear X-ray luminosity previously
observed in QSOs and bright Seyfert 1 galaxies appears to extend down into the
regime of ultra-low luminosity (L(x)~10^38 - 10^40 erg/s) active galactic
nuclei (AGN). The inferred accretion rates for this sample of low-luminosity
AGN are significantly sub-Eddington. In total 142 non-nuclear sources were
detected. In combination with published data for M31 this leads to a luminosity
distribution (normalised to an optical blue luminosity of L(B) = 10^10
L(solar)) for the discrete X-ray source population in spiral galaxies of the
form dN/dL38 = 1.0 +/- 0.2 L38^-1.8, where L38 is the X-ray luminosity in units
of 10^38 erg/s. The implied L(x)/L(B) ratio is ~1.1 x 10^39 erg/s/(10^10
L(solar)). The nature of the substantial number of ``super-luminous''
non-nuclear objects detected in the survey is discussed.

</DOC>
<DOC>
<DOCNO> 152060 </DOCNO>
Backreaction I: The Torus


  We use wrapped D-brane probes to measure position dependent perturbations of
compactification moduli. Due to the backreaction of the D-branes on the local
geometry, we suspect that measuring the fluctuations of one modulus to high
precision will generically affect the others. These considerations lead us to
conjecture a novel uncertainty principle on the Calabi-Yau moduli space. We
begin our investigation with a gedanken experiment on a torus.

</DOC>
<DOC>
<DOCNO> 121958 </DOCNO>
The Beta Problem: A Study of Abell 262


  We present an investigation of the dynamical state of the cluster A262.
Existing optical line of sight velocities for select cluster galaxies have been
augmented by new data obtained with the Automated Multi-Object Spectrograph at
Lick Observatory. We find evidence for a virialized early-type population
distinct from a late-type population infalling from the Pisces-Perseus
supercluster ridge. We also report on a tertiary population of low luminosity
galaxies whose velocity dispersion distinguishes them from both the early and
late-type galaxies. We supplement our investigation with an analysis of
archival X-ray data. A temperature is determined using ASCA GIS data and a gas
profile is derived from ROSAT HRI data. The increased statistics of our sample
results in a picture of A262 with significant differences from earlier work. A
previously proposed solution to the "beta-problem" in A262 in which the gas
temperature is significantly higher than the galaxy temperature is shown to
result from using too low a velocity dispersion for the early-type galaxies.
Our data present a consistent picture of A262 in which there is no
"beta-problem", and the gas and galaxy temperature are roughly comparable.
There is no longer any requirement for extensive galaxy-gas feedback to
drastically overheat the gas with respect to the galaxies. We also demonstrate
that entropy-floor models can explain the recent discovery that the beta values
determined by cluster gas and the cluster core radii are correlated.

</DOC>
<DOC>
<DOCNO> 40447 </DOCNO>
Rare Kaon Decays


  Rare kaon decays via Flavor Changing Neutral Currents are discussed in the
context of the CKM unitarity triangle with a particular interest in the rare
kaon decays K^+ --> pi^+ nu nubar and K^0_L --> pi^0 nu nubar. New results and
the status of these experiments are reported.

</DOC>
<DOC>
<DOCNO> 102774 </DOCNO>
Invitation to higher local fields, Part I, section 9: Exponential maps


  An exponential homomorphism for a complete discrete valuation field of
characteristic zero which relates differential forms and the Milnor K-groups of
the field is studied. An application to explicit formulas is included.

</DOC>
<DOC>
<DOCNO> 150440 </DOCNO>
A Note On Relation Between Holographic RG Equation And Polchinski's RG


  We clarify the relation between the recently formulated holographic
renormalization group equation and Polchinski's exact renormalization group
equation.

</DOC>
<DOC>
<DOCNO> 7793 </DOCNO>
Theory of Chiral Imprinting


  We present a continuum model for a nematic elastomer network formed in a
chiral environment, for instance in the presence of a chiral solvent. When this
environment is removed, the network can retain some memory of its chiral
genesis. We predict the residual chiral order parameter for a number of
possible scenarios, and go on to examine the robustness (stability) of the
imprinted chirality. We show that a twist-untwist transition can take place,
which determines whether the imprinting has been successful. A transition is
via a coarsening of the helical director pattern and a lengthening of its
pitch. Finally, the effect due to a subsequent swelling by an achiral solvent,
or by a solvent of differing chirality, is considered.

</DOC>
<DOC>
<DOCNO> 13090 </DOCNO>
Dynamics and delocalisation transition for an interface driven by a


  We study the effect of a uniform shear flow on an interface separating the
two broken-symmetry ordered phases of a two-dimensional system with
nonconserved scalar order parameter. The interface, initially flat and
perpendicular to the flow, is distorted by the shear flow. We show that there
is a critical shear rate, \gamma_c, proportional to 1/L^2, (where L is the
system width perpendicular to the flow) below which the interface can sustain
the shear. In this regime the countermotion of the interface under its
curvature balances the shear flow, and the stretched interface stabilizes into
a time-independent shape whose form we determine analytically. For \gamma >
\gamma_c, the interface acquires a non-zero velocity, whose profile is shown to
reach a time-independent limit which we determine exactly. The analytical
results are checked by numerical integration of the equations of motion.

</DOC>
<DOC>
<DOCNO> 40676 </DOCNO>
Composite Scalars at LEP: Constraining Technicolor Theories


  LEPI and LEPII data can be used to constrain technicolor models with light,
neutral pseudo-Nambu-Goldstone bosons, Pa. We use published limits on branching
ratios and cross sections for final states with photons, large missing energy,
jet pairs, and b bbar pairs to constrain the anomalous Pa Z0 Z0, Pa Z0 photon,
and Pa photon photon couplings. From these results, we derive bounds on the
size of the technicolor gauge group and the number of technifermion doublets in
models such as Low-scale Technicolor.

</DOC>
<DOC>
<DOCNO> 13157 </DOCNO>
Quantum Computing in Molecular Magnets


  Shor and Grover demonstrated that a quantum computer can outperform any
classical computer in factoring numbers and in searching a database by
exploiting the parallelism of quantum mechanics. Whereas Shor's algorithm
requires both superposition and entanglement of a many-particle system, the
superposition of single-particle quantum states is sufficient for Grover's
algorithm. Recently, the latter has been successfully implemented using Rydberg
atoms. Here we propose an implementation of Grover's algorithm that uses
molecular magnets, which are solid-state systems with a large spin; their spin
eigenstates make them natural candidates for single-particle systems. We show
theoretically that molecular magnets can be used to build dense and efficient
memory devices based on the Grover algorithm. In particular, one single crystal
can serve as a storage unit of a dynamic random access memory device. Fast
electron spin resonance pulses can be used to decode and read out stored
numbers of up to 10^5, with access times as short as 10^{-10} seconds. We show
that our proposal should be feasible using the molecular magnets Fe8 and Mn12.

</DOC>
<DOC>
<DOCNO> 179002 </DOCNO>
Relativistic Effects in Electroweak Nuclear Responses


  The electroweak response functions for inclusive electron scattering are
calculated in the Relativistic Fermi Gas model, both in the quasi-elastic and
in the $\Delta$ peak regions. The impact of relativistic kinematics at high
momentum transfer is investigated through an expansion in the initial nucleonic
momentum, which is however exact in the four-momentum of the exchanged boson.
The same expansion is applied to the meson exchange currents in the
particle-hole sector: it is shown that the non-relativistic currents can be
corrected by simple kinematical factors to account for relativity. The
left-right asymmetry measured via polarized electron scattering is finally
evaluated in the quasi-elastic and $\Delta$ peaks.

</DOC>
<DOC>
<DOCNO> 170171 </DOCNO>
Solution of the Deutsch-Josza Problem by NMR Ensemble Computing without


  Experimental NMR implementations of the Deutsch-Josza quantum algorithm based
on pesudo-pure spin states exhibit an exponential sensitivity scaling with the
number of qubits. By employing truly mixed spin states in spin Liouville space,
where molecules with different nuclear spin configurations represent different
input states, the Deutsch-Josza problem can be solved by single function
evaluation without sensitivity loss concomitant with increase of the number of
bits.

</DOC>
<DOC>
<DOCNO> 116833 </DOCNO>
Theory and Suppression of Multibunch Beam Breakup in Linear Colliders


  We recently developed an analytic theory of cumulative multibunch beam
breakup that includes a linear variation of transverse focusing across the
bunch train. The focusing variation saturates the exponential growth of the
beam breakup and establishes an algebraic decay of the transverse bunch
displacement versus bunch number. In this paper we illustrate how the focusing
variation works to suppress multibunch beam breakup, as well as how the
mechanism scales with accelerator and beam parameters.

</DOC>
<DOC>
<DOCNO> 7804 </DOCNO>
Chiral Twisting of a Smectic-A Liquid Crystal


  Chiral twisting of the molecular orientation within the layer of a smectic-A
liquid crystal has been investigated using circular dichroism spectroscopy. The
results indicate that a rotation of the layers away from the alignment
direction is induced by the surface electroclinic effect. This leads to an
interfacial region where the molecular director twists from the alignment
direction until it reaches the layer normal direction. A theory is presented to
explain the observed field and temperature dependence of the circular
dichroism.

</DOC>
<DOC>
<DOCNO> 119683 </DOCNO>
Measurement of the Parallax of PSR B0950+08 Using the VLBA


  A new technique has been developed to remove the ionosphere's distorting
effects from low frequency VLBI data. By fitting dispersive and non-dispersive
components to the phases of multi-frequency data, the ionosphere can be
effectively removed from the data without the use of {\em a priori} calibration
information. This technique, along with the new gating capability of the VLBA
correlator, was used to perform accurate astrometry on pulsar B0950+08,
resulting in a much improved measurement of this pulsar's proper motion
($\mu_{\alpha} = -1.6 \pm 0.4$ mas/yr, $\mu_{\delta} = 29.5 \pm 0.5$ mas/yr)
and parallax ($\pi = 3.6 \pm 0.3$ mas). This puts the pulsar at a distance of
$280 \pm 25$ parsecs, about twice as far as previous estimates, but in good
agreement with models of the electron density in the local bubble.

</DOC>
<DOC>
<DOCNO> 150637 </DOCNO>
Deformation Quantization of Bosonic Strings


  Deformation quantization of bosonic strings is considered. We show that the
light-cone gauge is the most convenient classical description to perform the
quantization of bosonic strings in the deformation quantization formalism.
Similar to the field theory case, the oscillator variables greatly facilitates
the analysis. The mass spectrum, propagators and the Virasoro algebra are
finally described within this deformation quantization scheme.

</DOC>
<DOC>
<DOCNO> 123169 </DOCNO>
Detailed abundance analysis of 8 super-metal-rich star candidates


  We provide detailed abundance analyses of 8 candidate super-metal-rich stars.
Five of them are confirmed to have [Fe/H] > 0.2 dex, the generally-accepted
limit for super-metal-richness. Furthermore, we derive abundances of several
elements and find that the stars follow trends seen in previous studies of
metal-rich stars. Ages are estimated from isochrones and velocities calculated.
We find that there do exist very metal-rich stars that are older than 10 Gyr.
This is contrary to what is found in several recent studies of the galactic
age-metallicity relation. This is tentative evidence that there might not exist
a one-to-one relation between age and metallicity for all stars. This is not
surprising considering the current models of the independent evolution of the
different galactic components. We also find that one star, HD 182572, could
with ~ 75 % chance be a thick disk star with, for the thick disk, an extremely
high metallicity at 0.34 dex. This star is, intriguingly, also somewhat
enhanced in the alpha-elements.

</DOC>
<DOC>
<DOCNO> 69919 </DOCNO>
Quark propagator in the Landau gauge


  The Landau gauge quark propagator in momentum space is investigated using the
O(a)-improved Sheikholeslami--Wohlert (SW) quark action with a tree-level
mean-field improved coefficient c_sw. We have studied the unimproved definition
of the quark propagator, as well as two different tree-level O(a)-improved
propagators. The ultraviolet behavior of the free lattice propagator is studied
for each of these in order to establish which of them provides the most
reliable description of the quark propagator up to the medium momentum regime.
A general method of tree-level correction is introduced. This exploits
asymptotic freedom and removes much of the trivial lattice artifacts at medium
to high momenta. We obtain results for the quark propagator which are
qualitatively similar to those typically used in quark models. A simple
extrapolation of the infrared quark mass M(p^2=0) to the chiral limit gives
(298+/-8+/-30) MeV, which is consistent with phenomenological expectations.

</DOC>
<DOC>
<DOCNO> 151892 </DOCNO>
Worldsheet of the discrete light front string


  Some aspects of light-like compactifications of superstring theory and their
implications for the matrix model of M-theory are discussed.

</DOC>
<DOC>
<DOCNO> 12056 </DOCNO>
Theory of tunable pH sensitive vesicles of anionic and cationic lipids


  The design of vesicles which become unstable at an easily tuned value of pH
is of great interest for targeted drug delivery. We present a microscopic
theory for two forms of such vesicles. A model of lipids introduced by us
previously is applied to a system of ionizable, anionic lipid, and permanently
charged, cationic lipid. We calculate the pH at which the lamellar phase
becomes unstable with respect to an inverted hexagonal one, a value which
depends continuously on the system composition. Identifying this instability
with that displayed by unilamellar vesicles undergoing fusion, we obtain very
good agreement with the recent experimental data of Hafez et al., Biophys. J.
2000 79: 1438-1446, on the pH at which fusion occurs vs. vesicle composition.
We explicate the mechanism in terms of the role of the counter ions. This
understanding suggests that a system of a neutral, non lamellar forming lipid
stabilized by an anionic lipid would serve equally well for preparing tunable,
pH sensitive vesicles. Our calculations confirm this. Further, we show that
both forms of vesicle have the desirable feature of exhibiting a regime in
which the pH at instability is a rapidly varying function of the vesicle
composition.

</DOC>
<DOC>
<DOCNO> 8031 </DOCNO>
Nonexistence of the non-Gaussian fixed point predicted by the RG field


  The Ginzburg-Landau phase transition model is considered in d=4-epsilon
dimensions within the renormalization group (RG) approach. The problem of
existence of the non-Gaussian fixed point is discussed. An equation is derived
from the first principles of the RG theory (under the assumption that the fixed
point exists) for calculation of the correction-to-scaling term in the
asymptotic expansion of the two-point correlation (Green's) function. It is
demonstrated clearly that, within the framework of the standard methods (well
justified in the vicinity of the fixed point) used in the perturbative RG
theory, this equation leads to an unremovable contradiction with the known RG
results. Thus, in its very basics, the RG field theory in 4-epsilon dimensions
is contradictory. To avoid the contradiction, we conclude that such a
non-Gaussian fixed point, as predicted by the RG field theory, does not exist.
Our consideration does not exclude existence of a different fixed point.

</DOC>
<DOC>
<DOCNO> 101961 </DOCNO>
Gauge Theory Techniques in Quantum Cohomology


  Quantum cohomology gives a finite dimensional integrable system via the
Dubrovin connection. Motivated by Givental's work on mirror symmetry, we use
gauge theory techniques and the Frobenius Integrability Theorem to find flat
sections for the Dubrovin connection. An explicit calculation is given for
projective space.

</DOC>
<DOC>
<DOCNO> 71486 </DOCNO>
A geometrical estimation of saturation of partonic densities


  We propose a new criterium for saturation of the density of partons both in
nucleons and nuclei. It is applicable to any multiple scattering model which
would be used to compute the number of strings exchanged in $ep$ and $eA$
collisions. The criterium is based on percolation of strings, and the onset of
percolation is estimated from expectations coming from the study of heavy ion
collisions at high energies. We interpret this onset as an indication of
saturation of the density of partons in the wave function of the hadron. In
order to produce quantitative results, a particular model fitted to describe
present HERA data and generalized to the nuclear case is used. Nevertheless,
with the number of scatterings controlled by the relation between inclusive and
diffractive processes, conclusions are weakly model-dependent as long as
different models are tuned to describe the experimental data. This constitutes
a new approach, based on the eikonal description of soft hadronic collisions,
and different from others which employ either perturbative QCD ideas or
semiclassical methods. It offers an alternative picture for saturation in the
small $Q^2$ region.

</DOC>
<DOC>
<DOCNO> 100198 </DOCNO>
Brown-Peterson spectra in stable A^1-homotopy theory


  We characterize ring spectra morphisms from the algebraic cobordism spectrum
$\QTR{Bbb}{MGL}$ (\QCITE{cite}{}{Vo1}) to an oriented spectrum $\QTR{Bbb}{E}$
(in the sense of Morel \QCITE{cite}{}{Mo}) via formal group laws on the
''topological'' subring $E^{*}=\oplus_iE^{2i,i}$ of $E^{**}$. This result is
then used to construct for any prime $p$ a motivic Quillen idempotent on
$\QTR{Bbb}{MGL}_{(p)}$. This defines the $BP$-spectrum associated to the prime
$p$ as in Quillen's \QCITE{cite}{}{Q1} for the complex-oriented topological
case.

</DOC>
<DOC>
<DOCNO> 83419 </DOCNO>
The Random Oracle Methodology, Revisited


  We take a critical look at the relationship between the security of
cryptographic schemes in the Random Oracle Model, and the security of the
schemes that result from implementing the random oracle by so called
"cryptographic hash functions". The main result of this paper is a negative
one: There exist signature and encryption schemes that are secure in the Random
Oracle Model, but for which any implementation of the random oracle results in
insecure schemes.
  In the process of devising the above schemes, we consider possible
definitions for the notion of a "good implementation" of a random oracle,
pointing out limitations and challenges.

</DOC>
<DOC>
<DOCNO> 11919 </DOCNO>
Influence of incommensurate dynamic charge-density wave scattering on


  We show that the spectral lineshape of superconducting
La$_{2-x}$Sr$_x$CuO$_4$ (LSCO) and Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ (Bi2212)
can be well described by the coupling of the charge carriers to collective
incommensurate charge-density wave (CDW) excitations. Our results imply that
besides antiferromagnetic (AF) fluctuations also low-energy CDW modes can
contribute to the observed dip-hump structure in the Bi2212 photoemission
spectra. In case of underdoped LSCO we propose a possible interpretation of
ARPES data in terms of a grid pattern of fluctuating stripes where the charge
and spin scattering directions deviate by $\alpha=\pi/4$. Within this scenario
we find that the spectral intensity along $(0,0) \to (\pi,\pi)$ is strongly
suppressed consistent with recent photoemission experiments. In addition the
incommensurate charge-density wave scattering leads to a significant broadening
of the quasiparticle-peak around $(\pi,0)$.

</DOC>
<DOC>
<DOCNO> 71259 </DOCNO>
Another Look at Charged Higgs Boson Production at LEP


  The current atmospheric and solar neutrino experimental data favors the
bi-maximal mixing solution of the Zee-type neutrino mass matrix in which
neutrino masses are generated radiatively. This model requires the existence of
a weak singlet charged Higgs boson. While low energy data are unlikely to
further constrain the parameters of this model, the direct search of charged
Higgs production at the CERN LEP experiments can provide useful information on
this mechanism of neutrino mass generation by analyzing their data with
electrons and/or muons (in contrast to taus or charms) in the final state with
missing transverse energies. We also discuss the difference in the production
rates of a weak singlet from a weak doublet charged Higgs boson pairs at LEP.

</DOC>
<DOC>
<DOCNO> 68152 </DOCNO>
Theory of epsilon'/epsilon


  I shortly review the present status of the theoretical estimates of eps'/eps.
I consider a few aspects of the theoretical calculations which may be relevant
in understanding the present experimental results. In particular, I discuss the
role of final state interactions and in general of non-factorizable
contributions for the explanation of the Delta I = 1/2 selection rule in kaon
decays and eps'/eps. Lacking reliable ``first principle'' calculations,
phenomenological approaches may help in understanding correlations among
theoretical effects and the experimental data. The same dynamics which
underlies the CP conserving selection rule drives eps'/eps in the range of the
recent experimental measurements.

</DOC>
<DOC>
<DOCNO> 84894 </DOCNO>
Entropy generation in cosmological particle creation


  A very simplified model of the Universe is considered in order to propose an
alternative approach to the irreversible evolution of the Universe at very
early times. The entropy generation at the quantum stage can be thought as a
consequence of an instability of the system. Then particle creation arises from
this instability.

</DOC>
<DOC>
<DOCNO> 7968 </DOCNO>
Conduction channels of superconducting quantum point contacts


  Atomic quantum point contacts accommodate a small number of conduction
channels. Their number N and transmission coefficients {T_n} can be determined
by analyzing the subgap structure due to multiple Andreev reflections in the
current-voltage (IV) characteristics in the superconducting state. With the
help of mechanically controllable break-junctions we have produced Al contacts
consisting of a small number of atoms. In the smallest stable contacts, usually
three channels contribute to the transport. We show here that the channel
ensemble {T_n} of few atom contacts remains unchanged up to temperatures and
magnetic fields approaching the critical temperature and the critical field,
respectively, giving experimental evidence for the prediction that the
conduction channels are the same in the normal and in the superconducting
state.

</DOC>
<DOC>
<DOCNO> 84283 </DOCNO>
Some Remarks on the Neutrino Oscillation Phase in a Gravitational Field


  The weak gravitational field expansion method to account for the
gravitationally induced neutrino oscillation effect is critically examined. It
is shown that the splitting of the neutrino phase into a ``kinematic'' and a
``gravitational'' phase is not always possible because the relativistic factor
modifies the particle interference phase splitting condition in a gravitational
field.

</DOC>
<DOC>
<DOCNO> 100958 </DOCNO>
Obstacles problems with measure data


  We give a definition for Obstacle Problems with measure data and general
obstacles. For such problems we prove existence and uniqueness of solutions and
consistency with the classical theory of Variational Inequalities. Continuous
dependence with respect to data is discussed.

</DOC>
<DOC>
<DOCNO> 116615 </DOCNO>
Quantum-like Chaos in Prime Number Distribution and in Turbulent Fluid


  Recent studies indicate a close association between the distribution of prime
numbers and quantum mechanical laws governing the subatomic dynamics of quantum
systems such as the electron or the photon. Number theoretical concepts are
intrinsically related to the quantitative description of dynamical systems of
all scales ranging from the microscopic subatomic dynamics to macroscale
turbulent fluid flows such as the atmospheric flows. It is now recognised that
Cantorian fractal spacetime characterise all dynamical systems in nature. A
cell dynamical system model developed by the author shows that the continuum
dynamics of turbulent fluid flows consist of a broadband continuum spectrum of
eddies which follow quantumlike mechanical laws. The model concepts enable to
show that the continuum real number field contains unique structures, namely
prime numbers which are analogous to the dominant eddies in the eddy continuum
in turbulent fluid flows. In this paper it is shown that the prime number
frequency spectrum follows quantumlike mechanical laws.

</DOC>
<DOC>
<DOCNO> 101453 </DOCNO>
Layered restrictions and Chebyshev polynomials


  A permutation is called layered if it consists of the disjoint union of
substrings (layers) so that the entries decrease within each layer, and
increase between the layers. We find the generating function for the number of
permutations on $n$ letters avoiding $(1,2,3)$ and a layered permutation on $k$
letters. In the most interesting case of two layers, the generating function
depends only on $k$ and is expressed via Chebyshev polynomials of the second
kind.

</DOC>
<DOC>
<DOCNO> 152093 </DOCNO>
Heat trace asymptotics of a time dependent process


  We study the heat trace asymptotics defined by a time dependent family of
operators of Laplace type which naturally appears for time dependent metrics.

</DOC>
<DOC>
<DOCNO> 170414 </DOCNO>
On the connection between the radial momentum operator and the


  The radial momentum operator in quantum mechanics is usually obtained through
canonical quantization of the (symmetrical form of the) classical radial
momentum. We show that the well known connection between the Hamiltonian of a
free particle and the radial momentum operator $\hat{H}=\hat{P}_{r}^2/2m+
$\hat{L}^2$}/2mr^{2}$ is true only in one or three dimensions. In general, an
extra term of the form $\hbar^{2}(n-1)(n-3)/ 2m \cdot 4r^{2}$ has to be added
to the Hamiltonian.

</DOC>
<DOC>
<DOCNO> 83162 </DOCNO>
A Polyvariant Binding-Time Analysis for Off-line Partial Deduction


  We study the notion of binding-time analysis for logic programs. We formalise
the unfolding aspect of an on-line partial deduction system as a Prolog
program. Using abstract interpretation, we collect information about the
run-time behaviour of the program. We use this information to make the control
decisions about the unfolding at analysis time and to turn the on-line system
into an off-line system. We report on some initial experiments.

</DOC>
<DOC>
<DOCNO> 40187 </DOCNO>
Jet Structure Studies at LEP and HERA


  A summary of some recent studies in jet physics is given. Topics include
leading particle production in light flavor events in e+e- annihilations, an
analytical treatment of gluon and quark jets at the
next-to-next-to-next-to-leading order (3NLO), and various studies performed at
LEP and HERA involving separated gluon and quark jets.

</DOC>
<DOC>
<DOCNO> 121788 </DOCNO>
Is there a maximum observable redshift in an open universe?


  An estimate of the maximum observable redshift is obtained using only t_{0}
approximately equal to (14+- 3)10^{9}years, H_{0} approximately equal to 65 +-
10Km\sec^{-1}Mpc^{-1}(t_{0}H_{0} approximately equal to 0.91 +- 0.08/0.18)
assuming \Lambda approximately equal to 0. The resulting maximum redshift z_{+}
approximately equal to 10 appears to give a reasonable upper limit to the
highest actually observed redshifts. Some implications are discussed.

</DOC>
<DOC>
<DOCNO> 120487 </DOCNO>
Thermal stability and nova cycles in permanent superhump systems


  Archival data on permanent superhump systems are compiled to test the thermal
stability of their accretion discs. We find that their discs are almost
certainly thermally stable as expected. This result confirms Osaki's suggestion
(1996) that permanent superhump systems form a new subclass of cataclysmic
variables (CVs), with relatively short orbital periods and high mass transfer
rates. We note that if the high accretion rates estimated in permanent
superhump systems represent their mean secular values, then their mass transfer
rates cannot be explained by gravitational radiation, therefore, either
magnetic braking should be extrapolated to systems below the period gap or they
must have mass transfer cycles. Alternatively, a new mechanism that removes
angular momentum from CVs below the gap should be invoked.
  We suggest applying the nova cycle scenarios offered for systems above the
period gap to the short orbital period CVs. Permanent superhumps have been
observed in the two non-magnetic ex-novae with binary periods below the gap.
Their post-nova magnitudes are brighter than their pre-outburst values. In one
case (V1974 Cyg) it has been demonstrated that the pre-nova should have been a
regular SU UMa system. Thus it is the first nova whose accretion disc was
observed to change its thermal stability. If the superhumps in this system
indicate persistent high mass transfer rates rather than a temporary change
induced by irradiation from the hot post-nova white dwarf, it is the first
direct evidence for mass transfer cycles in CVs. The proposed cycles are driven
by the nova eruption.

</DOC>
<DOC>
<DOCNO> 14084 </DOCNO>
Rotationally driven gas of inelastic rough spheres


  We study a two-dimensional gas of inelastic rough spheres, driven on the
rotational degrees of freedom. Numerical simulations are compared to mean-field
(MF) predictions with surprisingly good agreement for strong coupling of
rotational and translational degrees of freedom -- even for very strong
dissipation in the translational degrees. Although the system is spatially
homogeneous, the rotational velocity distribution is essentially Maxwellian.
Surprisingly, the distribution of tangential velocities is strongly deviating
from a Maxwellian. An interpretation of these results is proposed, as well as a
setup for an experiment.

</DOC>
<DOC>
<DOCNO> 13057 </DOCNO>
Theory of the Hall Coefficient and the Resistivity on the Layered


  In the organic superconducting \kappa-(BEDT-TTF) compounds, various transport
phenomena exhibit striking non-Fermi liquid behaviors, which should be the
important clues to understanding the electronic state of this system.
Especially, the Hall coefficient ($R_H$) shows Curie-Weiss type temperature
dependence, which is similar to that of high-Tc cuprates. In this paper, we
study a Hubbard model on an anisotropic triangular lattice at half filling,
which is an effective model of \kappa-(BEDT-TTF) compounds. Based on the
fluctuation-exchange (FLEX) approximation, we calculate the resistivity
($\rho$) and $R_H$ by taking account of the vertex corrections for the current,
which is necessary for satisfying the conservation laws. Our theoretical
results of $R_H$ and $cot(\theta_H)$ explain the experimental behaviors well,
which are unable to be reproduced by the conventional Boltzmann transport
approximation. Moreover, we extend the standard Eliashberg's transport theory
and derive the more precise formula for the conductivity, which becomes
important at higher temperatures.

</DOC>
<DOC>
<DOCNO> 80604 </DOCNO>
Smooth Gauge Strings and D>=2 Lattice Yang-Mills Theories


  Employing the nonabelian duality transformation, I derive the Gauge String
form of certain D>=3 lattice Yang-Mills (YM_{D}) theories in the strong
coupling (SC) phase. With the judicious choice of the actions, in D>=3 our
construction generalizes the Gross-Taylor stringy reformulation of the
continuous YM_{2} on a 2d manifold. Using the Eguchi-Kawai model as an example,
we develope the algorithm to determine the weights w[\tilde{M}] for connected
YM-flux worldsheets \tilde{M} immersed into the 2d skeleton of a D>=3
base-lattice. Owing to the invariance of w[\tilde{M}] under a continuous group
of area-preserving worldsheet homeomorphism, the set of the weights
{w[\tilde{M}]} can be used to define the theory of the smooth YM-fluxes which
unambiguously refers to a particular continuous YM_{D} system. I argue that the
latter YM_{D} models (with a finite ultraviolet cut-off) for sufficiently large
bare coupling constant(s) are reproduced, to all orders in 1/N, by the smooth
Gauge String thus associated. The asserted YM_{D}/String duality allows to make
a concrete prediction for the 'bare' string tension \sigma_{0} which implies
that (in the large N SC regime) the continuous YM_{D} systems exhibit
confinement for $D\geq{2}$. The resulting pattern is qualitatively consistent
(in the extreme D=4 SC limit) with the Witten's proposal motivated by the
AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 122658 </DOCNO>
Ambiguities in Determination Of Self-Affinity in the AE-index Time


  The interaction between the Earth's magnetic field and the solar wind plasma
results in a natural plasma confinement system which stores energy. Dissipation
of this energy through Joule heating in the ionosphere can be studied via the
 Auroral Electrojet (AE) index. The apparent broken power law form of the
frequency spectrum of this index has motivated investigation of whether it can
be described as fractal coloured noise. One frequently-applied test for
self-affinity is to demonstrate linear scaling of the logarithm of the
structure function of a time series with the logarithm of the dilation factor
$\lambda$. We point out that, while this is conclusive when applied to signals
that are self-affine over many decades in $\lambda$, such as Brownian motion,
the slope deviates from exact linearity and the conclusions become ambiguous
when the test is used over shorter ranges of $\lambda$. We demonstrate that non
self-affine time series made up of random pulses can show near-linear scaling
over a finite dynamic range such that they could be misinterpreted as being
self-affine. In particular we show that pulses with functional forms such as
those identified by Weimer within the $AL$ index, from which $AE$ is partly
derived, will exhibit nearly linear scaling over ranges similar to those
previously shown for $AE$ and $AL$. The value of the slope, related to the
Hurst exponent for a self-affine fractal, seems to be a more robust
discriminator for fractality, if other information is available.

</DOC>
<DOC>
<DOCNO> 67662 </DOCNO>
Diffraction and the Pomeron


  Recent experimental results on inclusive diffractive scattering and on
exclusive vector meson production are reviewed. The dynamical picture of hard
diffraction emerging in perturbative QCD is highlighted.

</DOC>
<DOC>
<DOCNO> 150337 </DOCNO>
A new "polarized version" of the Casimir Effect is measurable


  We argue that the exactly computable, angle dependent, Casimir force between
parallel plates with different directions of conductivity can be measured.

</DOC>
<DOC>
<DOCNO> 13633 </DOCNO>
Superconducting Gap Anisotropy in Nd$_{1.85}$Ce$_{0.15}$CuO$_4$: Results


  We have performed angle resolved photoelectron spectroscopy on the electron
doped cuprate superconductor Nd$_{1.85}$Ce$_{0.15}$CuO$_4$. A comparison of the
leading edge midpoints between the superconducting and normal states reveals a
small, but finite shift of 1.5-2 meV near the ($\pi$,0) position, but no
observable shift along the zone diagonal near ($\pi$/2,$\pi$/2). This is
interpreted as evidence for an anisotropic superconducting gap in the electron
doped materials, which is consistent with the presence of d-wave
superconducting order in this cuprate superconductor.

</DOC>
<DOC>
<DOCNO> 69907 </DOCNO>
Hot Dark Matter in Cosmology


  Cosmological dark matter in the form of neutrinos with masses of up to a few
electron volts is known as hot dark matter. After an historical review of the
subject, this article considers constraints on hot dark matter from current
data on neutrino oscillations and on cosmology. The atmospheric neutrino
oscillation data imply a lower limit on the HDM contribution to the
cosmological density $\Omega_\nu \gsim 0.001$. The possible improvement of
low-$\Omega_m$ flat ($\Lambda$CDM) cosmological models with the addition of
light neutrinos appears to be rather limited, but$\Lambda$CDM models with
$\Omega_\nu \lsim 0.1$ may be consistent with presently available data. Data
expected soon may permit detection of such a hot dark matter contribution, or
alternatively provide stronger upper limits on $\Omega_\nu$ and neutrino
masses.

</DOC>
<DOC>
<DOCNO> 68121 </DOCNO>
Finite T meson correlations and quark deconfinement


  Finite temperature spatial $\bar q q$ correlation modes in the $\pi$ and
$\rho$ channels are studied with the rainbow-ladder truncated quark
Dyson-Schwinger equation and Bethe-Salpeter equation in the Matsubara
formalism. To retain the finite range of the effective interaction while
facilitating summation over fermion Matsubara modes necessary to ensure
continuity at {T=0}, a separable kernel is used. The model is fixed by {T=0}
properties and it implements dynamical chiral symmetry breaking and quark
confinement. Above and below the deconfinement and chiral restoration
transitions, we study $M_\pi(T)$, $f_\pi(T)$ and the 3-space transverse and
longitudinal masses $M_\rho^T(T)$ and $M_\rho^L(T)$. For the $\rho$ mode we
also study the strong and electromagnetic partial widths to determine the
$T$-dependence that is generated by the quark content. The $\rho \to \pi \pi$
width decreases sharply just above the chiral restoration transition leaving
the $\rho$ with only its narrow {$e^+ e^-$} width. We discuss improvements
needed by this model, especially in regard to the high $T$ behavior of the
masses where we compare to lattice QCD simulations.

</DOC>
<DOC>
<DOCNO> 14073 </DOCNO>
On random graphs and the statistical mechanics of granular matter


  The dynamics of spins on a random graph with ferromagnetic three-spin
interactions is used to model the compaction of granular matter under a series
of taps. Taps are modelled as the random flipping of a small fraction of the
spins followed by a quench at zero temperature. We find that the density
approached during a logarithmically slow compaction
 - the random-close-packing density - corresponds to a dynamical phase
transition. We discuss the the role of cascades of successive spin-flips in
this model and link them with density-noise power fluctuations observed in
recent experiments.

</DOC>
<DOC>
<DOCNO> 40639 </DOCNO>
A Biased Review of Tau Neutrino Mass Limits


  After a quick review of astrophysically relevant limits, I present a summary
of MeV scale tau neutrino mass limits derived from accelerator based
experiments.
 I argue that the current published limits appear to be too consistent, and
that we therefore cannot conclude that the tau neutrino mass limit is as low as
usually claimed. I provide motivational arguments calling into question the
assumed statistical properties of the usual maxumum likelihood estimators, and
provide a prescription for deriving a more robust and understandable mass
limit.

</DOC>
<DOC>
<DOCNO> 71719 </DOCNO>
The bound on the mass of the new gauge boson $Z^{\prime}$ from the


  The new gauge boson $Z^{\prime}$ predicted by the strong top dynamical
symmetry breaking models has significant contributions to the lepton flavor
changing process $\mu\longrightarrow 3e $. We consider the bound on the mass of
the new gauge boson $Z^{\prime}$ from the experimental value of the branching
ratio $Br(\mu\longrightarrow 3e)$ in the framework of topcolor assisted
technicolor models. We find that the precision experimental value of
$Br(\mu\longrightarrow 3e)$ gives a severe bound on the $Z^{\prime}$ mass
$M_{Z^{\prime}}$. For $k_1 \leq 1$, $M_{Z^{\prime}}$ must be larger than 1.64
$TeV$.

</DOC>
<DOC>
<DOCNO> 10833 </DOCNO>
Fractons and Luttinger liquids


  We consider the concept of fractons as particles or quasiparticles which obey
a specific fractal statistics in connection with a one-dimensional Luttinger
liquid theory. We obtain a dual statistics parameter ${\tilde{\nu}}=\nu+1$
which is identified with the controlling parameter $e^{-2\phi}$ of the
Luttinger model. In this way, a bosonic system characterized by a fractal index
$i_{f}[h]=i_{f}[2]=1$ is considered as a conformal field theory with central
charge $c[\nu=0]=1=i_{f}[2]$ with a compactified radius
$R=\frac{1}{\sqrt{\tilde{\nu}}}=1$. Thus, we have a mapping of a bosonic theory
to a fermionic one and vice-versa, i.e., the duality symmetry ${{\tilde{h}}
=3-h}$ of the universal class $h$ of fractons defined in the interval 1< h <2
is satisfied.

</DOC>
<DOC>
<DOCNO> 12718 </DOCNO>
Discretized Diffusion Processes


  We study the properties of the ``Rigid Laplacian'' operator, that is we
consider solutions of the Laplacian equation in the presence of fixed
truncation errors. The dynamics of convergence to the correct analytical
solution displays the presence of a metastable set of numerical solutions,
whose presence can be related to granularity. We provide some scaling analysis
in order to determine the value of the exponents characterizing the process. We
believe that this prototype model is also suitable to provide an explanation of
the widespread presence of power-law in social and economic system where
information and decision diffuse, with errors and delay from agent to agent.

</DOC>
<DOC>
<DOCNO> 69924 </DOCNO>
Higgs-Boson Production and Decay Close to Thresholds


  At one loop in the conventional on-mass-shell renormalization scheme, the
production and decay rates of the Higgs boson H exhibit singularities
proportional to (2 M_V - M)^{-1/2} as the Higgs-boson mass M approaches from
below the pair-production threshold of a vector boson V with mass M_V. This
problem is of phenomenological interest because the values 2 M_W and 2 M_Z,
corresponding to the W- and Z-boson thresholds, lie within the M range
presently favoured by electroweak precision data. We demonstrate how these
threshold singularities are eliminated when the definitions of mass and total
decay width of the Higgs boson are based on the complex-valued pole of its
propagator. We illustrate the phenomenological implications of this
modification for the partial width of the H -> W^+ W^- decay.

</DOC>
<DOC>
<DOCNO> 68978 </DOCNO>
Confronting Dilaton-exchange gravity with experiments


  We study the experimental constraints on theories, where the equivalence
principle is violated by dilaton-exchange contributions to the usual
graviton-exchange gravity. We point out that in this case it is not possible to
have any CPT violation and hence there is no constraint from the CPT violating
measurements in the $K-$system. The most stringent bound is obtained from the
$K_L - K_S$ mass difference. In contrast, neither neutrino oscillation
experiments nor neutrinoless double beta decay imply significant constraints.

</DOC>
<DOC>
<DOCNO> 69081 </DOCNO>
On nuclear matrix element uncertainties in short range 0vBB decay


  The evaluation of short range contributions to neutrinoless double beta decay
has been challenged due to critics of the ansatz of the nuclear matrix element
calculations. We comment on the critics and uncertainties of these calculations
and the effect on the derived limits.

</DOC>
<DOC>
<DOCNO> 80914 </DOCNO>
Two-colour QCD at finite fundamental quark-number density and related


  We are simulating SU(2) Yang-Mills theory with four flavours of dynamical
quarks in the fundamental representation of SU(2) `colour' at finite chemical
potential, mu for quark number, as a model for QCD at finite baryon number
density. In particular we observe that for mu large enough this theory
undergoes a phase transition to a state with a diquark condensate which breaks
quark-number symmetry. In this phase we examine the spectrum of light scalar
and pseudoscalar bosons and see evidence for the Goldstone boson associated
with this spontaneous symmetry breaking. This theory is closely related to QCD
at finite chemical potential for isospin, a theory which we are now studying
for SU(3) colour.

</DOC>
<DOC>
<DOCNO> 12162 </DOCNO>
Kinetics of Strongly Non-Equilibrium Bose-Einstein Condensation


  We consider the ordering kinetics in a strongly non-equilibrium state of a
(weakly) interacting Bose gas, characterized, on one hand, by large occupation
numbers, and, on the other hand, by the absence of long-range order. Up to
higher-order corrections in inverse occupation numbers, the evolution is
described by non-linear Schrodinger equation with a turbulent initial state.
The ordering process is rather rich and involves a number of qualitatively
different regimes that take place in different regions of energy space.
Specially addressed is the case of evolution in an external potential.

</DOC>
<DOC>
<DOCNO> 84767 </DOCNO>
The Quantum States and the Statistical Entropy of the Charged Black Hole


  We quantize the Reissner-Nordstr\"om black hole using an adaptation of
Kucha\v{r}'s canonical decomposition of the Kruskal extension of the
Schwarzschild black hole. The Wheeler-DeWitt equation turns into a functional
Schroedinger equation in Gaussian time by coupling the gravitational field to a
reference fluid or dust. The physical phase space of the theory is spanned by
the mass, $M$, the charge, $Q$, the physical radius, $R$, the dust proper time,
$\tau$, and their canonical momenta. The exact solutions of the functional
Schroedinger equation imply that the difference in the areas of the outer and
inner horizons is quantized in integer units. This agrees in spirit, but not
precisely, with Bekenstein's proposal on the discrete horizon area spectrum of
black holes. We also compute the entropy in the microcanonical ensemble and
show that the entropy of the Reissner-Nordstr\"om black hole is proportional to
this quantized difference in horizon areas.

</DOC>
<DOC>
<DOCNO> 85051 </DOCNO>
Trajectories for the Wave Function of the Universe from a Simple


  Inspired by Mott's (1929) analysis of particle tracks in a cloud chamber, we
consider a simple model for quantum cosmology which includes, in the total
Hamiltonian, model detectors registering whether or not the system, at any
stage in its entire history, passes through a series of regions in
configuration space. We thus derive a variety of well-defined formulas for the
probabilities for trajectories associated with the solutions to the
Wheeler-DeWitt equation. The probability distribution is peaked about classical
trajectories in configuration space. The ``measured'' wave functions still
satisfy the Wheeler-DeWitt equation, except for small corrections due to the
disturbance of the measuring device. With modified boundary conditions, the
measurement amplitudes essentially agree with an earlier result of Hartle
derived on rather different grounds. In the special case where the system is a
collection of harmonic oscillators, the interpretation of the results is aided
by the introduction of ``timeless'' coherent states -- eigenstates of the
Hamiltonian which are concentrated about entire classical trajectories.

</DOC>
<DOC>
<DOCNO> 123059 </DOCNO>
Ram-Pressure Stripping of Galaxies in High-Redshift Clusters and


  We have investigated the ram-pressure stripping of disk galaxies in clusters
at various redshifts and in cluster progenitors; the clusters grow up on a
hierarchical clustering scenario. We consider a radially infalling galaxy whose
initial position and velocity are given by a spherical collapse model of
structure formation. Moreover, since observations show that the intracluster
medium (ICM) of nearby clusters is non-gravitationally heated, we study the
effect of the non-gravitational heating on the ram-pressure stripping. For a
given redshift, we find that ram-pressure stripping has more influence on
galaxies in more massive clusters. On the other hand, for a given mass, it has
more influence on galaxies in the clusters at higher redshifts. In particular,
we predict that in rich clusters at z ~> 1, most of the galaxies are affected
by the ram-pressure stripping. While the non-gravitational heating
significantly reduces the influence of ram-pressure stripping on galaxies in
clusters with mass smaller than 1-5 10^13 M_sun, it does not affect the
influence in richer clusters. If the ICM is heated non-gravitationally at z>>1,
ram-pressure stripping does not occur at z ~ 1-2 in the progenitors of clusters
observed at 0 ~< z ~< 0.5, because the heat makes the ICM fraction of the
cluster progenitors small. On the other hand, if the ICM is heated
non-gravitationally at z ~ 0 for the first time, the ram-pressure stripping
occurs even at z ~ 3. We compare the results with the observations of galaxies
in clusters at various redshifts.

</DOC>
<DOC>
<DOCNO> 68373 </DOCNO>
Spherical Scalar Field Halo in Galaxies


  We study a spherically symmetric fluctuation of scalar dark matter in the
cosmos and show that it could be the dark matter in galaxies, provided that the
scalar field has an exponential potential whose overall sign is negative and
whose exponent is constrained observationally by the rotation velocities of
galaxies. The local space-time of the fluctuation contains a three dimensional
space-like hypersurface with surplus of angle.

</DOC>
<DOC>
<DOCNO> 84928 </DOCNO>
Exact Inflationary Models and Consequences


  New exact inflationary solutions are presented in the scalar field theory,
minimally coupled to gravity, with a potential term. No use is made of the slow
rollover approximation. The scale factors are completely nonsingular and the
transition to the deccelerating phase is smooth. Moreover, in one of these
models, asymptotically one has transition to the matter dominated Universe.

</DOC>
<DOC>
<DOCNO> 85310 </DOCNO>
Can the gamma-ray source 3EG J2033+4118 be produced by the stellar


  We discuss the possibility that the stellar system Cyg OB2 No.5 can be a
gamma-ray source in the light of recent EGRET and radio data. This system is
formed by an O7 Ia + Ofpe/WN9 contact binary. A third star, probably a B0 V
star also associated with the system, is located at $\sim 1700$ AU from the
primary. We estimate the expected gamma-ray luminosity from the colliding winds
region, the terminal shock of the wind, and the unstable zone at the base of
the wind, and conclude that, under very reasonable assumptions, Cyg OB2 No.5
can generate about a half of the gamma-ray flux detected from the positionally
coincident source 3EG J2033+4118. We suggest, then, that other O stars
belonging to the association, also placed within the 95 % probability EGRET
location contour, could contribute to the observed gamma-ray flux.

</DOC>
<DOC>
<DOCNO> 69076 </DOCNO>
Duality in the non-relativistic harmonic oscillator quark model in the


  The detailed way in which duality between sum of exclusive states and the
free quark model description operates in semileptonic total decay widths, is
analysed. It is made very explicit by the use of the non relativistic harmonic
oscillator quark model in the SV limit, and a simple interaction current with
the lepton pair. In particular, the Voloshin sum rule is found to eliminate the
mismatches of order $\delta m/m_b^2$.

</DOC>
<DOC>
<DOCNO> 100939 </DOCNO>
BPS states and algebras from quivers


  We discuss several aspects of D-brane moduli spaces and BPS spectra near
orbifold points. We give a procedure to determine the decay products on a line
of marginal stability, and we define the algebra of BPS states in terms of
quivers. These issues are illustrated in detail in the case of type IIA theory
on C^2/Z_N. We also show that many of these results can be extended to
arbitrary points in the compactification moduli space using Pi-stability.

</DOC>
<DOC>
<DOCNO> 9577 </DOCNO>
Slow Coarsening in a Class of Driven Systems


  The coarsening process in a class of driven systems is studied. These systems
have previously been shown to exhibit phase separation and slow coarsening in
one dimension. We consider generalizations of this class of models to higher
dimensions. In particular we study a system of three types of particles that
diffuse under local conserving dynamics in two dimensions. Arguments and
numerical studies are presented indicating that the coarsening process in any
number of dimensions is logarithmically slow in time. A key feature of this
behavior is that the interfaces separating the various growing domains are
smooth (well approximated by a Fermi function). This implies that the
coarsening mechanism in one dimension is readily extendible to higher
dimensions.

</DOC>
<DOC>
<DOCNO> 178530 </DOCNO>
Collective states in nuclei and many-body random interactions


  Low-lying collective states in nuclei are investigated in the framework of
the interacting boson model using an ensemble of random many-body interactions.
It is shown that whenever the number of bosons is sufficiently large compared
to the rank of the interactions, the spectral properties are characterized by a
dominance of L(P)=0(+) ground states and the occurrence of both vibrational and
rotational band structures. This indicates that these features represent a
general and robust property of the collective model space.

</DOC>
<DOC>
<DOCNO> 8455 </DOCNO>
Magnetic free energy at elevated temperatures and hysteresis of magnetic


  We derive a free energy for weakly anisotropic ferromagnets which is valid in
the whole temperature range and interpolates between the micromagnetic energy
at zero temperature and the Landau free energy near the Curie point T_c. This
free energy takes into account the change of the magnetization length due to
thermal effects, in particular, in the inhomogeneous states. As an
illustration, we study the thermal effect on the Stoner-Wohlfarth curve and
hysteresis loop of a ferromagnetic nanoparticle assuming that it is in a
single-domain state. Within this model, the saddle point of the particle's free
energy, as well as the metastability boundary, are due to the change in the
magnetization length sufficiently close to T_c, as opposed to the usual
homogeneous rotation process at lower temperatures.

</DOC>
<DOC>
<DOCNO> 71073 </DOCNO>
Phase Transition in Hot Pion Matter


  The equation of state for the pion gas is analyzed within the third virial
approximation. The second virial coefficient is found from the pion-pion-
scattering data, while the third one is considered as a free parameter. The
proposed model leads to a first-order phase transition from the pion gas to a
more dense phase at the temperature T_pt < 136 MeV. Due to relatively low
temperature this phase transition cannot be related to the deconfinement. This
suggests that a new phase of hadron matter - 'hot pion liquid' - may exist.

</DOC>
<DOC>
<DOCNO> 67667 </DOCNO>
A note on low scale unification and gamma-gamma scattering


  In this note we study an interesting effect of low energy gravity on
photon-photon scattering at high energies.

</DOC>
<DOC>
<DOCNO> 9315 </DOCNO>
First-order theta-point of a single polymer chain


  Conformational transitions of a single macromolecule of finite size $N$
cannot be described within standard thermodynamic framework. Taking as a basis
a simple model of homopolymer exhibiting a coil-globule transition, we show
that a relevant approach is to describe the thermal equilibrium distribution
$P_N^{(\beta)}(t)$ of some variable $t$ characterizing the conformation.
Although the mean order parameter exhibits a second-order behaviour in the
infinite-size limit, the $\Theta$-point arises from the coexistence of two
distinct populations, associated with two well-separated peaks of
$P_N^{(\beta)}(t)$ and identified respectively with a coil state and a globule
state. Remarkably, this first-order feature increases with the size of the
chain. It allows to describe the transition within a two-state model,
well-suited to analyse experimental data.

</DOC>
<DOC>
<DOCNO> 99674 </DOCNO>
Groebner Basis Procedures for Testing Petri Nets


  This paper contains introductory material on Petri nets and Groebner basis
theory and makes some observations on the relation between the two areas. The
aim of the paper is to show how Groebner basis procedures can be applied to the
problem of reachability in Petri nets, and to give details of an application to
testing models of navigational systems.

</DOC>
<DOC>
<DOCNO> 121191 </DOCNO>
ASCA and other contemporaneous observations of the blazar B2 1308+326


  The high redshift (z=0.997) blazar B2 1308+326 was observed contemporaneously
at x-ray, optical and radio wavelengths in June 1996. The x-ray observations
were performed with ASCA. The ASCA results were found to be consistent with
reanalysed data from two earlier ROSAT observations. The combined ASCA and
ROSAT data reveal an x-ray spectrum that is best fit by a broken power law with
absorber model. The break in the x-ray spectrum is interpreted, to be the
emerging importance of inverse Compton (IC) emission which dominates the ASCA
spectrum. The faint optical state reported for these observations
(m_V=18.3+/-0.25) is incompatible with the high synchrotron flux previously
detected by ROSAT. The IC emission detected by both ROSAT and ASCA was not
significantly affected by the large change in the synchrotron component. MgII
emission was detected with an equivalent width (EW) significantly different
from previously reported values. Absorption at a level of in excess of the
Galactic value was detected, indicating the possible presence of a foreground
absorber. A gravitational microlensing scenario cannot therefore be ruled out
for this blazar. B2 1308+326 could be a typical radio-selected BL Lac in terms
of peak synchrotron frequency and optical and radio variability but its high
bolometric luminosity, variable line emission and high Doppler boost factor
make it appear more like a quasar than a BL Lac. It is suggested that B2
1308+326 be considered as the prototype of this class of composite source.

</DOC>
<DOC>
<DOCNO> 67773 </DOCNO>
Hard Loop Approach to Anisotropic Systems


  Anisotropic systems of quarks and gluons, which at least for sufficiently
short space-time intervals can be treated as homogeneous and static, are
considered. The gluon polarization tensor of such a system is explicitly
computed within the semiclassical kinetic and Hard Loop diagrammatic theories.
The equivalence of the two approaches is demonstrated. The quark self energy is
computed as well, and finally, the dispersion relations of quarks and gluons in
the anisotropic medium are discussed.

</DOC>
<DOC>
<DOCNO> 117542 </DOCNO>
Spectra of High Redshift Galaxies using a Cluster as a Gravitational


  Using the Focal Reducer Spectrograph (FORS) at the Very Large Telescope (VLT)
during the FORS commissioning time in December 1998 we took long slit spectra
of the gravitational arc visible on images of the galaxy cluster 1E 0657 (z =
0.296). This cluster is one of the hottest (massive) cluster known so far and
hence perfectly acts as a gravitational telescope magnifying the flux of
background sources up to a factor of 17. Here we present the spectra of the
gravitational arc (z = 3.23) and 4 additional high redshift objects (z=2.35 to
3.09), that also fall on the slit by chance coincidence. We briefly discuss the
stellar contents of these galaxies and show first models of the observed
spectra. Furthermore we point out the effectivity of using FORS in combination
with available gravitational telescopes.

</DOC>
<DOC>
<DOCNO> 99965 </DOCNO>
Twisted traces of quantum intertwiners and quantum dynamical R-matrices


  This paper is a continuation of math.QA/9907181 and math.QA/9908115. We
consider traces of intertwiners between certain representations of the
quantized enveloping algebra associated to a semisimple complex Lie algebra g,
which are twisted by a ``generalized Belavin-Drinfeld triple'', i.e a triple
consisting of two subdiagrams of the Dynkin diagram of g together with an
isomorphism between them. The generating functions F(lambda,mu) for such traces
depend on two weights lambda and mu. We show that F(lambda,mu) satisfy two sets
of difference equations in the variable lambda: the Macdonald-Ruijsenaars (MR)
equations and the quantum Knizhnik-Zamolodchikov
 (qKZB) equations. These equations involve as a main ingredient the quantum
dynamical R-matrices constructed in math.QA/9912009. When the generalized
Belavin-Drinfeld triple is an automorphism, we show that F(lambda,mu) satisfy
another two sets of difference equations with respect to the weight mu. These
dual MR and dual qKZB equations involve the usual Felder's dynamical R-matrix.
These results were first obtained by the first author and A. Varchenko in the
special case of the trivial Belavin-Drinfeld triple. However, the symmetry
between lambda and mu which exists in that case is destroyed in the twisted
setting. At the end, we brielfly treat the (simialr) case of Kac-Moody algebras
g and derive the classical limits of all the previous results.

</DOC>
<DOC>
<DOCNO> 150996 </DOCNO>
Black string instabilities in anti-de Sitter space


  We show how to extend the usual black string instability of vacuum or charged
black p-branes to the anti-de Sitter background. The string fragments in an
analogous fashion to the $\Lambda=0$ case, the main difference being that
instead of a periodic array of black holes forming, an accumulation of ``mini''
black holes occurs towards the AdS horizon. In the case where the AdS space is
of finite extent, such as an orbifold compactification, we show how the
instability switches off below a certain compactification scale.

</DOC>
<DOC>
<DOCNO> 99906 </DOCNO>
Exactly solvable two-dimensional Schrodinger operators and Laplace


  Different cases of sequences of the Laplace Transformations for the 2D
Schrodinger operator in the periodic magnetic field and electric potential are
considered. They lead to the exactly solvable operators with nonstandard
spectral properties including the double-periodic operators with algebraic
Fermi surface known from the periodic soliton theory. Two appendices are added.
In the Appendix I (the author - S. Novikov) two discretizations of the 2D
operators and Laplace transformations are constructed. In the Appendix II (the
authors - S. Novikov and I. Taimanov) some nonstandard 1D discrete operators
are constructed with very interesting spectral properties.

</DOC>
<DOC>
<DOCNO> 8707 </DOCNO>
Bond-Ordering Model for the Glass Transition


  We consider the idea of bond ordering as a model for glass transition: a
generic covalently bonded liquid may substantially reduce its energy through
bond ordering, without undergoing significant structural order. This concept is
developed for a model system using quantities such as a bond order parameter
and susceptibility which provide new identification for calorimetric glass
transition temperature. Monte Carlo simulation results exhibit bond ordering at
intermediate temperatures uncorrelated with any long-range structural ordering.
Also discussed are various other implications of bond-ordering model for glass
transition.

</DOC>
<DOC>
<DOCNO> 71013 </DOCNO>
Observing an invisible Higgs boson


  Given its weak coupling to bottom quarks and tau leptons, the Higgs boson may
predominantly decay into invisible particles like gravitinos, neutralinos, or
gravitons. We consider the manifestation of such an invisibly decaying Higgs
boson in weak boson fusion at the CERN LHC. Distinctive kinematic distributions
of the two quark jets of the signal as compared to Zjj and Wjj backgrounds
allow to restrict the Higgs branching ratio to 'invisible' final states to some
13% with 10fb^{-1} of data, provided events with two energetic forward jets of
high dijet invariant mass and with substantial missing transverse momentum can
be triggered efficiently. It is also possible to discover these particles with
masses up to 480 GeV in weak boson fusion, at the 5 sigma level, provided their
invisible branching ratio is close to 100%.

</DOC>
<DOC>
<DOCNO> 102791 </DOCNO>
Invitation to higher local fields, Part II, section 7: Recovering higher


  A main problem in Galois theory is to characterize the fields with a given
absolute Galois group. We apply a K-theoretic method for constructing
valuations to study this problem in various situations. As a first application
we obtain an algebraic proof of the 0-dimensional case of Grothendieck's
anabelian conjecture (proven by Pop), which says that finitely generated
infinite fields are determined up to purely inseparable extensions by their
absolute Galois groups. As a second application (which is a joint work with
Fesenko) we analyze the arithmetic structure of fields with the same absolute
Galois group as a higher-dimensional local field.

</DOC>
<DOC>
<DOCNO> 69165 </DOCNO>
Generations of Higgs Bosons in Supersymmetric Models


  We examine extensions of the MSSM with more than one generation of Higgs
bosons. If one assumes that a symmetry eliminates the tree-level FCNC, then the
extra scalar bosons do not acquire VEVs, do not couple to fermions and do not
mix with the ordinary Higgs bosons; the lightest is absolutely stable. The two
lightest neutral scalars, $\phi_S$, and $\phi_P$, are degenerate in mass, and
the mass difference between those and the lightest charged scalar, $\phi_+$, is
calculated. For most of the parameter space, the charged scalar is between a
hundred MeV and a few GeV heavier than the neutral scalars. The $\phi_+$ will
decay at the vertex; the signature for this decay will be like that of a
chargino with a nearly degenerate undetected neutralino. Next, the possibility
that the symmetry that eliminates FCNC is a flavor symmetry is discussed. In an
example, the U(2) model, tree-level FCNC processes can be calculated in terms
of quark masses. The strongest constraint on this model is from $D-\bar{D}$
mixing, which should be within an order of magnitude of the current bound.

</DOC>
<DOC>
<DOCNO> 120875 </DOCNO>
Evolution of Buoyant Bubbles in M87


  The morphology of the X-ray and radio emitting features in the central $\sim$
50 kpc region around the galaxy M87 strongly suggests that buoyant bubbles of
cosmic rays (inflated by an earlier nuclear active phase of the galaxy) rise
through the cooling gas at roughly half the sound speed. In the absence of
strong surface tension, initially spherical bubbles will transform into tori as
they rise through an external medium. Such structures can be identified in the
radio images of the halo of M87. During their rise, bubbles will uplift
relatively cool X-ray emitting gas from the central regions of the cooling flow
to larger distances. This gas is colder than the ambient gas and has a higher
volume emissivity. As a result, rising ``radio'' bubbles may be trailed by
elongated X-ray features as indeed is observed in M87. We performed simple
hydrodynamic simulations to qualitatively illustrate the evolution of buoyant
bubbles in the M87 environment.

</DOC>
<DOC>
<DOCNO> 120788 </DOCNO>
The mass distribution in the innermost regions of Spiral Galaxies


  We use high-spatial resolution ($\sim 100 pc$) rotation curves of 83 spiral
galaxies to investigate the mass distribution of their innermost kpc. We show
that, {\it in this region}, the luminous matter completely accounts for the
gravitational potential and no dark component is required. The derived I-band
disk mass-to-light ratios agree well with those obtained from population
synthesis models and correlate with color in a similar way. We find strict
upper limits of $\sim 10^7 M_\odot$ for the masses of compact bodies at the
center of spirals, ruling out that these systems host the remnants of the
quasar activity.

</DOC>
<DOC>
<DOCNO> 118547 </DOCNO>
Phase space transport in cuspy triaxial potentials: Can they be used to


  (Abridged) This paper studies chaotic orbit ensembles evolved in triaxial
generalisations of the Dehnen potential which have been proposed to model
ellipticals with a strong density cusp that manifest significant deviations
from axisymmetry. Allowance is made for a possible supermassive black hole, as
well as low amplitude friction, noise, and periodic driving which can mimic
irregularities associated with discreteness effects and/or an external
environment. The degree of chaos is quantified by determining how (1) the
relative number of chaotic orbits and (2) the size of the largest Lyapunov
exponent depend on the steepness of the cusp and the black hole mass, and (3)
the extent to which Arnold webs significantly impede phase space transport,
both with and without perturbations. In the absence of irregularities, chaotic
orbits tend to be extremely `sticky,' so that different pieces of the same
chaotic orbit can behave very differently for 10000 dynamical times or longer,
but even very low amplitude perturbations can prove efficient in erasing many
-- albeit not all -- these differences. The implications thereof are discussed
both for the structure and evolution of real galaxies and for the possibility
of constructing approximate near-equilibrium models using Schwarzschild's
method. Much of the observed qualitative behaviour can be reproduced with a toy
potential given as the sum of an anisotropic harmonic oscillator and a
spherical Plummer potential, which suggests that the results may be generic.

</DOC>
<DOC>
<DOCNO> 11940 </DOCNO>
Superconductive proximity effect in interacting disordered conductors


  We present a general theory of the superconductive proximity effect in
disordered normal--superconducting (N-S) structures, based on the recently
developed Keldysh action approach. In the case of the absence of interaction in
the normal conductor we reproduce known results for the Andreev conductance G_A
at arbitrary relation between the interface resistance R_T and the diffusive
resistance R_D. In two-dimensional N-S systems, electron-electron interaction
in the Cooper channel of normal conductor is shown to strongly affect the value
of G_A as well as its dependence on temperature, voltage and magnetic field. In
particular, an unusual maximum of G_A as a function of temperature and/or
magnetic field is predicted for some range of parameters R_D and R_T. The
Keldysh action approach makes it possible to calculate the full statistics of
charge transfer in such structures. As an application of this method, we
calculate the noise power of an N-S contact as a function of voltage,
temperature, magnetic field and frequency for arbitrary Cooper repulsion in the
normal metal and arbitrary values of the ratio R_D/R_T.

</DOC>
<DOC>
<DOCNO> 170062 </DOCNO>
Phenomenological approach to introduce damping effects on radiation


  In this work we propose an approach to deal with radiation field states which
incorporates damping effects at zero temperature. By using some well known
results on dissipation of a cavity field state, obtained by standard ab-initio
methods, it was possible to infer through a phenomenological way the explicit
form for the evolution of the state vector for the whole system: the
cavity-field plus reservoir. This proposal turns out to be of extreme
convenience to account for the influence of the reservoir over the cavity
field.
  To illustrate the universal applicability of our approach we consider the
attenuation effects on cavity-field states engineering. A proposal to maximize
the fidelity of the process is presented.

</DOC>
<DOC>
<DOCNO> 119627 </DOCNO>
An Extragalactic HI Cloud with No Optical Counterpart?


  We report the discovery, from the HI Parkes All-Sky Survey (HIPASS), of an
isolated cloud of neutral hydrogen which we believe to be extragalactic. The HI
mass of the cloud (HIPASS J1712-64) is very low, 1.7 x 10^7 Msun, using an
estimated distance of ~3.2 Mpc. Most significantly, we have found no optical
companion to this object to very faint limits (mu(B)~ 27 mag arcsec^-2). HIPASS
J1712-64 appears to be a binary system similar to, but much less massive than,
HI 1225+01 (the Virgo HI Cloud) and has a size of at least 15 kpc. The mean
velocity dispersion, measured with the Australia Telescope Compact Array
(ATCA), is only 4 km/s for the main component and because of the weak or
non-existent star-formation, possibly reflects the thermal linewidth (T<2000 K)
rather than bulk motion or turbulence. The peak column density for HIPASS
J1712-64, from the combined Parkes and ATCA data, is only 3.5 x 10^19 cm^-2,
which is estimated to be a factor of two below the critical threshold for star
formation. Apart from its significantly higher velocity, the properties of
HIPASS J1712-64 are similar to the recently recognised class of Compact High
Velocity Clouds. We therefore consider the evidence for a Local Group or
Galactic origin, although a more plausible alternative is that HIPASS J1712-64
was ejected from the interacting Magellanic Cloud/Galaxy system at
perigalacticon ~ 2 x 10^8 yr ago.

</DOC>
<DOC>
<DOCNO> 11102 </DOCNO>
Large oxygen-isotope effect in Sr_{0.4}K_{0.6}BiO_{3}: Evidence for


  Oxygen-isotope effect has been investigated in a recently discovered
superconductor Sr_{0.4}K_{0.6}BiO_{3}. This compound has a distorted perovskite
structure and becomes superconducting at about 12 K. Upon replacing ^{16}O with
^{18}O by 60-80%, the T_c of the sample is shifted down by 0.32-0.50 K,
corresponding to an isotope exponent of alpha_{O} = 0.40(5). This isotope
exponent is very close to that for a similar bismuthate superconductor
Ba_{1-x}K_{x}BiO_{3} with T_c = 30 K. The very distinctive doping and T_c
dependencies of alpha_{O} observed in bismuthates and cuprates suggest that
bismuthates should belong to conventional phonon-mediated superconductors while
cuprates might be unconventional supercondutors.

</DOC>
<DOC>
<DOCNO> 12398 </DOCNO>
WWW and Internet models from 1955 till our days and the ``popularity is


  We note that the model discussed in the communication of S. Bornholdt and H.
Ebel (World Wide Web scaling exponent from Simon's 1955 model,
cond-mat/0008465) is the particular case of the model considered and solved
exactly in our paper, cond-mat/0004434. These models may be used for estimation
of the order of the deviation of the scaling exponent from 2 both for the
distributions of incoming links and links coming out from nodes but not for the
obtaining some specific values of the exponents from the WWW growth data. We
emphasize that, unlike the statement of Bornholdt and Ebel, both the network
under consideration and the model of Barab\'{a}si and Albert provide quite
equal possibilities for individual growth. There is no great difference between
them in this respect. The resulting distributions for individual nodes and
arising scaling relations have been obtained in our paper, cond-mat/0004434. We
discuss briefly the modern state of art in the physics of the evolving networks
and the great role of the general principle -- {\em popularity is attractive}
-- in the self-organization of complex communications networks, in physics of
nonequilibrium phenomena, and in Nature.

</DOC>
<DOC>
<DOCNO> 178775 </DOCNO>
E1 transitions between spin-dipole and Gamow-Teller giant resonances


  The branching ratios for E1 transitions between the spin-dipole (SD) and
Gamow-Teller (GT) giant resonances in $^{90}$Nb and $^{208}$Pb are evaluated.
Assuming the main GT-state has the wave function close to that for the "ideal"
GT-state, we reduced the problem to calculate the SD and GT strength functions.
These strength functions are evaluated within an extended continuum-RPA
approach.

</DOC>
<DOC>
<DOCNO> 72136 </DOCNO>
New algebraic-numeric methods for loop integrals. Some 1-loop experience


  We report our experiences with the generalized integration-by-parts algorithm
[hep-ph/9609429] in the context of calculations of a realistic one-loop subset
of diagrams.

</DOC>
<DOC>
<DOCNO> 118804 </DOCNO>
Non-conservative Evolution of Cataclysmic Variables


  We suggest a new mechanism to account for the loss of angular momentum in
binaries with non-conservative mass exchange. It is shown that in some cases
the loss of matter can result in increase of the orbital angular momentum of a
binary. If included into consideration in evolutionary calculations, this
mechanism appreciably extends the range of mass ratios of components for which
mass exchange in binaries is stable. It becomes possible to explain the
existence of some observed cataclysmic binaries with high donor/accretor mass
ratio, which was prohibited in conservative evolution models.

</DOC>
<DOC>
<DOCNO> 68986 </DOCNO>
Propagation of polarized high-energy photons in crystals


  The density matrix is obtained for short-wavelength photons passing through a
medium. For sufficiently large thicknesses of a target this matrix is expressed
by the forward scattering amplitude of a photon. For multi-GeV photons
scattering via virtual electron-positron pairs is the most important process.
Its amplitude in a crystal is calculated. The results obtained are used to find
the optimal thicknesses, orientations and types of crystals for the circular -
to - linear polarization conversion process.

</DOC>
<DOC>
<DOCNO> 151444 </DOCNO>
Logarithmic operators in the SL(2,R) WZNW model


  We find some exact solutions of the Knizhnik-Zamolodchikov equation for the
four point correlation functions that occur in the SL(2,R) WZNW model. They
exhibit logarithmic behaviour in both the Kac-Moody and Virasoro parts. We
discuss their implication for the operator product expansion. We also observe
the appearance of several symmetries of the correlation functions.

</DOC>
<DOC>
<DOCNO> 84381 </DOCNO>
Double Scalar-Tensor Gravity Cosmologies


  We investigate homogeneous and isotropic cosmological models in scalar-tensor
theories of gravity where two scalar fields are nonminimally coupled to the
geometry. Exact solutions are found, by Noether symmetries, depending on the
form of couplings and self-interaction potentials. An interesting feature is
that we deal with the Brans-Dicke field and the inflaton on the same ground
since both are nonminimally coupled and not distinguished {\it a priori} as in
earlier models. This fact allows to improve dynamics to get successful extended
inflationary scenarios. Double inflationary solutions are also discussed.

</DOC>
<DOC>
<DOCNO> 71496 </DOCNO>
Unitarity and Asymptotic Behavior of Amplitudes in Non-Anticommutative


  The unitarity condition for scattering amplitudes in a non-anticommutative
quantum field theory is investigated. The Cutkosky rules are shown to hold for
Feynman diagrams in Euclidean momentum space and unitarity of amplitudes can be
satisfied. An analytic continuation of the diagrams to physical Minkowski
spacetime can be performed without invoking unphysical singularities in
amplitudes. The high energy behavior of amplitudes is found to be regular at
infinity provided that only space-space non-anticommutativity is allowed.

</DOC>
<DOC>
<DOCNO> 117597 </DOCNO>
The Spectroscopic Orbit of the Planetary Companion Transiting HD209458


  We report a spectroscopic orbit with period P = 3.52433 +/- 0.00027 days for
the planetary companion that transits the solar-type star HD209458. For the
metallicity, mass, and radius of the star we derive [Fe/H] = 0.00 +/- 0.02, M =
1.1 +/- 0.1 solar masses, and R = 1.3 +/- 0.1 solar radii. This is based on a
new analysis of the iron lines in our HIRES template spectrum, and also on the
absolute magnitude and color of the star, and uses isochrones from four
different sets of stellar evolution models. Using these values for the stellar
parameters we reanalyze the transit data and derive an orbital inclination of i
= 85.2 +/- 1.4 degrees. For the planet we derive a mass of Mp = 0.69 +/- 0.05
Jupiter masses, a radius of Rp = 1.54 +/- 0.18 Jupiter radii, and a density of
0.23 +/- 0.08 grams per cubic cm.

</DOC>
<DOC>
<DOCNO> 9757 </DOCNO>
Low-energy charge dynamics in


  Direct experimental estimations of the low-energy ($1.5\sim10$ meV) complex
dielectric constants spectrum and its temperature variation have been
investigated for La$_{0.7}$Ca$_{0.3}$MnO$_3$ thin films using terahertz
time-domain spectroscopy. At low temperatures, a clear Drude-term emerges. With
increasing temperature, the scattering rate increases, while the plasma
frequency decreases, derived both from a simple Drude model. Finally, a
Drude-term submerges well below the insulator-metal transition temperature. On
the basis of the present results, low-energy charge dynamics are discussed.

</DOC>
<DOC>
<DOCNO> 118506 </DOCNO>
Homogeneity of Stellar Populations in Early-Type Galaxies with Different


  We have found the stellar populations of early-type galaxies are homogeneous
with no significant difference in color or Mg2 index, despite the dichotomy
between X-ray extended early-type galaxies and X-ray compact ones. Since the
X-ray properties reflect the potential gravitational structure and hence the
process of galaxy formation, the homogeneity of the stellar populations implies
that the formation of stars in early-type galaxies predat es the epoch when the
dichotomy of the potential structure was established.

</DOC>
<DOC>
<DOCNO> 70690 </DOCNO>
On the number of colours in Quantum Chromodynamics


  It is commonly believed that ${\pi}^0 \to 2 \gamma$ decay shows that there
are three colours in Quantum Chromodynamics (QCD). It is shown here that this
is not correct. When correct colour dependent charges of the quarks are
considered then it is shown that this decay does not make any statement about
the number of colours in QCD.

</DOC>
<DOC>
<DOCNO> 116801 </DOCNO>
Inversionless gain in a three-level system driven by a strong field and


  Inversionless gain in a three-level system driven by a strong external field
and by collisions with a buffer gas is investigated. The mechanism of
populating of the upper laser level contributed by the collision transfer as
well as by relaxation caused by a buffer gas is discussed in detail. Explicit
formulae for analysis of optimal conditions are derived. The mechanism
developed here for the incoherent pump could be generalized to other systems.

</DOC>
<DOC>
<DOCNO> 100036 </DOCNO>
Remarks on plane maximal curves


  Some new results on plane F_{q^2}-maximal curves are stated and proved. It is
known that the degree d of such curves is upper bounded by q+1 and that d=q+1
if and only if the curve is F_{q^2}-isomorphic to the Hermitian. We show that
d\le q+1 can be improved to d\le (q+2)/2 apart from the case d=q+1 or q\le 5.
This upper bound turns out to be sharp for q odd. We also study the maximality
of Hurwitz curves of degree n+1. We show that they are F_{q^2}-maximal if and
only if (q+1) divides (n^2-n+1). Such a criterion is extended to a wider family
of curves.

</DOC>
<DOC>
<DOCNO> 118032 </DOCNO>
Stability of Relativistic Blast Waves


  A spherical blast wave with relativistic velocity can be described by a
similarity solution, that is used for theoretical models of gamma-ray bursts.
We consider the linear stability of such a relativistic blast wave propagating
into a medium with density gradient. The perturbation can also be expressed by
a self-similar form. We show that the shock front is unstable in general, and
we evaluate the growth rate.

</DOC>
<DOC>
<DOCNO> 118338 </DOCNO>
Hard X-Ray Spectra of Broad-Line Radio Galaxies from the Rossi X-Ray


  We present the results of hard-X-ray observations of four broad-line radio
galaxies (BLRGs) with the Rossi X-Ray Timing Explorer (RXTE). The original
motivation behind the observations was to search for systematic differences
between the BLRGs and their radio-quiet counterparts, the Seyfert galaxies. We
do, indeed, find that the Fe K-alpha lines and Compton "reflection" components,
which are hallmarks of the X-ray spectra of Seyferts galaxies, are weaker in
BLRGs by about a factor of 2. This observational result is in agreement with
the conclusions of other recent studies of these objects. We examine several
possible explanations for this systematic difference, including beaming of the
primary X-rays away from the accretion disk, a low iron abundance, a small
solid angle subtended by the disk to the primary X-ray source, and dilution of
the observed spectrum by beamed X-rays from the jet. We find that a small solid
angle subtended by the disk to the primary X-ray source is a viable and
appealing explanation, while all others suffer from drawbacks. We interpret
this as an indication of a difference in the inner accretion disk structure
between Seyfert galaxies and BLRGs, namely that the inner accretion disks of
BLRGs have the form of an ion-supported torus or an advection-dominated
accretion flow, which irradiates the geometrically thin outer disk.

</DOC>
<DOC>
<DOCNO> 8416 </DOCNO>
Random Fixed Point of Three-Dimensional Random-Bond Ising Models


  The fixed-point structure of three-dimensional bond-disordered Ising models
is investigated using the numerical domain-wall renormalization-group method.
It is found that, in the +/-J Ising model, there exists a non-trivial fixed
point along the phase boundary between the paramagnetic and ferromagnetic
phases. The fixed-point Hamiltonian of the +/-J model numerically coincides
with that of the unfrustrated random Ising models, strongly suggesting that
both belong to the same universality class. Another fixed point corresponding
to the multicritical point is also found in the +/-J model. Critical properties
associated with the fixed point are qualitatively consistent with theoretical
predictions.

</DOC>
<DOC>
<DOCNO> 102265 </DOCNO>
Completely tubing compressible tangles and standard graphs in genus one


  We prove a conjecture of Menasco and Zhang that if a tangle is completely
tubing compressible then it consists of at most two families of parallel
strands. This is related to problems of graphs in 3-manifold. A 1-vertex graph
$\Gamma$ in a 3-manifold $M$ with a genus 1 Heegaard splitting is standard if
it consists of one or two parallel sets of core curves lying in the Heegaard
splitting solid tori of $M$ in the standard way. The above conjecture then
follows from the theorem which says that a 1-vertex graph in $M$ is standard if
and only if the exteriors of all its nontrivial subgraphs are handlebodies.

</DOC>
<DOC>
<DOCNO> 118069 </DOCNO>
Metallicity Evolution in the Early Universe


  Observations of the damped Lya systems provide direct measurements on the
chemical enrichment history of neutral gas in the early universe. In this
Letter, we present new measurements for four damped Lya systems at high
redshift. Combining these data with [Fe/H] values culled from the literature,
we investigate the metallicity evolution of the universe from z~1.5-4.5.
Contrary to our expectations and the predictions of essentially every chemical
evolution model, the N(HI)-weighted mean [Fe/H] metallicity exhibits minimal
evolution over this epoch. For the individual systems, we report tentative
evidence for an evolution in the unweighted [Fe/H] mean and the scatter in
[Fe/H] with the higher redshift systems showing lower scatter and lower typical
[Fe/H] values. We also note that no damped Lya system has [Fe/H] < -2.7 dex.
Finally, we discuss the potential impact of small number statistics and dust on
our conclusions and consider the implications of these results on chemical
evolution in the early universe.

</DOC>
<DOC>
<DOCNO> 122450 </DOCNO>
The red stellar population in NGC 1569


  We present HST NICMOS photometry of the resolved stellar population in NGC
1569. The CMD in the F110W and F160W photometric bands contains ~2400 stars
with a formal photometric error < 0.1 mag down to J~23.5 and H~22.5. We
describe the data processing which is required to calibrate the instrumental
peculiarities of NICMOS. Two different packages for PSF-fitting photometry are
used to strengthen the photometric results in the crowded stellar field of NGC
1569. The resulting CMD is discussed in terms of the major evolutionary
properties of the resolved stellar populations. For a distance modulus of 26.71
and a reddening E(B-V)=0.56, our CMD samples stars down to ~0.8 Mo,
corresponding to look-back times > 15 Gyr. This is clear indication of SF
activity spanning an entire Hubble time. The metallicity of the reddest RGB
stars is in better agreement with Z=0.004 as measured in HII regions, than with
Z=0.0004 as expected from the stellar ages. The presence of - yet undetected -
very metal-poor stars embedded in the stellar distribution around J=22.75 and
J-H=1.15 is, however, not ruled out. The youngest stars (< 50 Myr) are
preferentially found around the two central super star clusters, whereas the
oldest population has a more uniform spatial distribution. A SFR per unit area
of 1 Mo yr*(-1) kpc*(-2) and a mass formed in stars of ~ 1.4x10*6 Mo in the
last 50 Myr are derived from the CMD. The NIR CMD places strong constraints on
the lower limit of the onset of SF in NGC 1569. The exceptionally high crowding
in the NICMOS images of NGC 1569 is a challenge for the photometric analysis.
As a result, optical and NIR images of NGC 1569 sample different populations
and cannot be cross-correlated. Nevertheless, we demonstrate the consistency of
the SF histories derived from the optical and NIR CMDs.

</DOC>
<DOC>
<DOCNO> 120973 </DOCNO>
Comparing Giant Molecular Clouds in M31, M33 & the Milky Way


  We present new observations of a 2' field in the north-eastern spiral arm of
M31. In the 0.8 x 3.6 kpc mosaicked region, we have detected six distinct,
large complexes of molecular gas, most of which lie along the spiral arm dust
lane or in the vicinity of HII regions. The mean properties of these complexes
are as follows: diameter ~ 57+/-13 pc, fwhm velocity ~ 6.5+/-1.2 km/s, M(CO) ~
3.0+/-1.6 x 10^5 solar masses, peak brightness temperatures ~ 1.6--4.2 K. We
investigate the effects of spatial filtering on the quantitative comparison of
Local Group and Milky Way giant molecular clouds properties and distributions.
We also discuss different cloud identification techniques and their impact on
derived cloud properties. When we employ the same cloud identification method
and account for differences in data acquisition for M31, Milky Way, and M33, we
find that the molecular cloud complexes in all three galaxies are similar.
While the global distribution of molecular gas may vary from galaxy to galaxy,
cloud complexes are similar, suggesting that cloud formation and destruction is
determined by local physics. This work is supported by grants AST-9613716 &
AST-9981289 from the National Science Foundation.

</DOC>
<DOC>
<DOCNO> 170802 </DOCNO>
Possibility for Teleportation of Nuclei


  Experimental realizations of QT have so far been limited to teleportation of
light. The present communication gives a new experimental scheme for QT of
heavy matter. We show that the standard experimental technique used in nuclear
physics may be successfully applied to teleportation of spin states of atomic
nuclei.
  It was shown that there are no theoretical prohibitions upon a possibility of
a complete Bell measurement, so that implementation of all four quantum
communication channels is at least theoretically available. A general
expression for scattering amplitude of two 1/2-spin particles was given in the
Bell operator basis, and peculiarities of Bell states registration are briefly
discussed.

</DOC>
<DOC>
<DOCNO> 119506 </DOCNO>
X-ray Continuum Slope and X-ray Spectral Features in NLS1 Galaxies


  The idea that some of the unusual features in the X-ray spectra of
Narrow-Line Seyfert 1 galaxies (NLS1s) are due to the steep X-ray continuum is
tested by comparing photoionization model calculations with various observed
properties of Seyfert 1 galaxies. A meaningful comparison must involve the
careful use of the right X-ray ionization parameter, designated here U(oxygen).
When this is done, it is found that the strength of the continuum absorption
features is insensitive to the exact slope of the 0.1-50 keV continuum. It is
also shown that the complex of iron L-shell lines near 1 keV can produce strong
absorption and emission features, depending on the gas distribution and line
widths. While this may explain some unusual X-ray features in AGN, the
predicted intensity of the features do not distinguish NLS1 from broader line
sources. Finally, acceleration of highly ionized gas, by X-ray radiation
pressure, is also not sensitive to the exact slope of the X-ray continuum.

</DOC>
<DOC>
<DOCNO> 68427 </DOCNO>
Multiplicity distribution tails at high eneries energies


  The idea that the hard channels may dominate in the very high multiplicity
processes is investigated. Quantitative realization of the `hard Pomeron', deep
inelastic scattering and large-angle annihilation mechanism combinations are
considered in the pQCD frame for this purpose.

</DOC>
<DOC>
<DOCNO> 123327 </DOCNO>
Optical and X-ray clusters as tracers of the supercluster-void network.


  We present a comparison of Abell and APM clusters of galaxies as tracers of
the large scale structure of the Universe. We investigate selection functions
of both cluster catalogs. We show that the supercluster-void network can be
traced with both cluster samples; the network has a well-defined period of ~120
h^{-1} Mpc. We calculate the correlation function and the power spectrum for
Abell and APM cluster samples. The APM cluster sample with measured redshifts
covers a small volume which contains only a few very rich superclusters that
surround one void and have exceptionally large mutual separations. Due to this
property the maximum of the power spectrum of APM clusters with measured
velocities is shifted to larger scales than the corresponding feature in the
power spectrum of Abell clusters. We conclude that the APM sample is not
representative for the large-scale structure as a whole due to the small space
coverage. We present a catalog of superclusters of galaxies, based on APM
clusters up to a redshift z_{lim}=0.13.

</DOC>
<DOC>
<DOCNO> 122876 </DOCNO>
The Formation of Black-Hole X-Ray Transients


  Studies of the observed characteristics of black-hole (BH) X-ray binaries can
be provide us with valuable information about the process of BH formation. In
this paper I address some of the aspects of our current understanding of BH
formation in binaries and point out some of the existing problems of current
theoretical models. In particular, the measured orbital periods and donor-star
properties indicate that a common-envelope phase appears to be a necessary
ingredient of the evolutionary history of observed BH X-ray transients, and
that it must be associated only with a modest orbital contraction. The timing
of this common-envelope phase is crucial in determining the final BH masses and
current evolutionary models of mass-losing massive stars place strong
constraints on the possible masses for immediate BH progenitors and wind mass
loss from helium stars. Last, it is interesting that, even in the absence of
any source of mass loss, the highest helium-star masses predicted by current
evolutionary models are still not high enough to account for the measured BH
mass in V404 Cyg (>10 solar masses). An alternative for the formation of
relatively massive BH may be provided by the evolutionary sequence proposed by
Eggleton & Verbunt (1986), which invokes hierarchical triples as progenitors of
BH X-ray binaries with low-mass companions.

</DOC>
<DOC>
<DOCNO> 8088 </DOCNO>
Experimental search for molecular-nuclear transitions in water


  Experimental search for molecular-nuclear transitions
H_2O\to^{18}Ne^*(4.522,1^-)\to^{18}F\to^{18}O in water molecules was carried
out. The measurements were performed in a low-background laboratory at the
Baksan Neutrino Observatory. Under the assumption that the above transitions
take place, the estimate for the half-life time of water molecule was found to
be about 10^{18} years.

</DOC>
<DOC>
<DOCNO> 117133 </DOCNO>
Bunch Length Measurements at the ATF Damping Ring in April 2000


  This report presents bunch length and energy spread measurements performed in
April 2000 at the ATF Damping Ring, at KEK. Measurements were performed with
the beam on and then off the linear (difference) coupling resonance. Due to
strong intra-beam scattering in the ATF ring, the results depended strongly on
the coupling.

</DOC>
<DOC>
<DOCNO> 13912 </DOCNO>
Should we abandon cascade models to describe the spatial complexity of


  We perform one- and two-points magnitude cumulant analysis of one-dimensional
longitudinal velocity profiles stemming from three different experimental
set-ups and covering a broad range of Taylor scaled Reynolds numbers from 89 to
2500. While the first-order cumulant behavior is found to strongly depend on
Reynolds number and experimental conditions, the second-order cumulant and the
magnitude connected correlation functions are shown to display respectively
universal scale and space-lag behavior. Despite the fact that the Extended
Self-Similarity (ESS) hypothesis is not consistent with these findings, when
extrapolating our results to the limit of infinite Reynolds number, one
confirms the validity of the log-normal multifractal description of the
intermittency phenomenon with a well defined intermittency parameter C2 = 0.025
+/- 0.003. But the convergence to zero of the magnitude connected correlation
functions casts doubt on the asymptotic existence of an underlying
multiplicative cascading spatial structure.

</DOC>
<DOC>
<DOCNO> 67699 </DOCNO>
Search Strategies for Non-Standard Higgs Bosons at Future e^+e^-


  Already in the simplest two-Higgs-doublet model with CP violation in the
Higgs sector, the $3\times3$ mixing matrix for the neutral Higgs bosons can
substantially modify their couplings, thereby endangering the ``classical''
Higgs search strategies. However, there are sum rules relating Yukawa and
Higgs-Z couplings which ensure that the ZZ, $b\anti b$ and $t\anti t$ couplings
of a given neutral 2HDM Higgs boson cannot all be simultaneously suppressed.
This result implies that any single Higgs boson will be detectable at an e^+e^-
collider if the Z+Higgs, $b\anti b+$Higgs {\it and} $t\anti t+$Higgs production
channels are all kinematically accessible {\it and} if the integrated
luminosity is sufficient. We explore, as a function of Higgs mass, the
luminosity required to guarantee Higgs boson detection, and find that for
moderate $\tan\beta$ values the needed luminosity is unlikely to be available
for all possible mixing scenarios. The additional difficulties for the case
when the two-doublet Higgs sector is extended by adding one more singlet are
summarized. Implications of the sum rules for Higgs discovery at the Tevatron
and LHC are briefly discussed.

</DOC>
<DOC>
<DOCNO> 70398 </DOCNO>
The abundance of relativistic axions in a flaton model of Peccei-Quinn


  Flaton models of Peccei-Quinn symmetry have good particle physics motivation,
and are likely to cause thermal inflation leading to a well-defined cosmology.
They can solve the $\mu$ problem, and generate viable neutrino masses.
Canonical flaton models predict an axion decay constant F_a of order 10^{10}
GeV and generic flaton models give F_a of order 10^9 GeV as required by
observation. The axion is a good candidate for cold dark matter in all cases,
because its density is diluted by flaton decay if F_a is bigger than 10^{12}
GeV. In addition to the dark matter axions, a population of relativistic axions
is produced by flaton decay, which at nucleosynthesis is equivalent to some
number \delta N_\nu of extra neutrino species. Focussing on the canonical
model, containing three flaton particles and two flatinos, we evaluate all of
the flaton-flatino-axion interactions and the corresponding axionic decay
rates. They are compared with the dominant hadronic decay rates, for both DFSZ
and KSVZ models. These formulas provide the basis for a precise calculation of
the equivalent \delta N_\nu in terms of the parameters (masses and couplings).
The KSVZ case is probably already ruled out by the existing bound \delta
N_\nu\lsim 1. The DFSZ case is allowed in a significant region of parameter
space, and will provide a possible explanation for any future detection of
nonzero $\delta N_\nu$.

</DOC>
<DOC>
<DOCNO> 116932 </DOCNO>
Frequency dependent hyperpolarizabilities of atoms; calculations using


  Using the orbitals generated by the van Leeuwen-Baerends potential, we
calculate frequency dependent response properties of noble gas atoms of He, Ne
and Ar and alkaline earth atoms Be and Mg, with particlar emphasis on their
nonlinear polarizabilities. For this we employ time-dependent Kohn-Sham
formalism with adiabatic local-density aproximation (ALDA) for exchange and
correlation. We show that results thus obtained for frequency dependent
polarizabilities of the inert gas atoms are highly acurate. On the other hand,
polarizabilities of the alkaline earths are not given with the same accuracy.
In light of this, we make an assessment of ALDA for obtaining linear and
nonlinear response properties by employing time-dependent density-functional
theory.

</DOC>
<DOC>
<DOCNO> 10739 </DOCNO>
Superfluid transition temperature from the Lindemann-like criterion


  We further analyze the recently proposed criterion, according to which a
superfluid transition occurs whenever the r.m.s. displacement of a particle
from its initial position in imaginary time reaches a certain fraction of the
interparticle distance. The critical temperature $T_\lambda$ is expressed in
terms of the single particle mobility. Within the Drude approximation for the
mobility $T_\lambda$ is determined by the friction coefficient (or by the
viscosity for dense liquids). To check the validity of the criterion the
resulting formula is applied to non-ideal Bose gas, to liquid helium and to
$^3$He-$^4$He mixtures. A reasonable qualitative agreement with available
experiments is obtained in all cases. In the case of the Bose gas the present
approach results also in an upper bound on the peak value of
$T_{\lambda}/T_{\lambda}^0$, where $T_{\lambda}^0$ is the critical temperature
for the ideal gas.

</DOC>
<DOC>
<DOCNO> 118431 </DOCNO>
Primordial black holes, phase transitions, and the fate of the universe


  Phase transitions in the early universe are prime settings for the production
of primordial black holes, since they can break the relatively quiescent
homogeneity and isotropy of Friedmann-Robertson-Walker (FRW) cosmologies. These
epochs of "symmetry breaking," moreover, can affect the subsequent development
of spacetime by changing the evolution of some FRW parameters, including the
present age and density of the universe. We discuss the relative importance of
such effects on constraining mechanisms of black hole formation.

</DOC>
<DOC>
<DOCNO> 121311 </DOCNO>
Secular Evolution of the Galactic Disk


  In the solar-neighbourhood, older stars have larger random velocities than
younger ones. It is argued that the increase in velocity dispersion with time
is predominantly a gradual process rather than one induced by discrete events
such as minor mergers. Ephemeral spiral arms seem to be the fundamental drivers
of disk heating, although scattering by giant molecular clouds plays an
important moderating role. In addition to heating the disk, spiral arms cause
stars' guiding centres to diffuse radially. The speed of this diffusion is
currently controversial.
  Data from the Hipparcos satellite has made it clear that the Galaxy is by no
means in a steady state. This development enormously increases the complexity
of the models required to account for the data. There are preliminary
indications that we see in the local phase-space distribution the dynamical
footprints of long-dissolved spiral waves.

</DOC>
<DOC>
<DOCNO> 151774 </DOCNO>
Consistency of Higher Derivative Gravity in the Brane Background


  We consider the theory of higher derivative gravity with non-factorizable
Randall-Sundrum type space-time and obtain the metric solutions which
characterize the $p$-brane world-volume as a curved or planar defect embedded
in the higher dimensions. We consider the string inspired effective actions of
the dilatonic Gauss-Bonnet type in the brane background and show its
consistency with the RS brane-world scenario and the conformal weight of the
dilaton couplings in the string theory with apppropriate choice of Regge slope
($\alpha'$) or Gauss-Bonnet coupling ($\alpha$) or both. We also discuss a time
dependent dilaton solution for a string-inspired fourth-derivative gravity.

</DOC>
<DOC>
<DOCNO> 68491 </DOCNO>
Scaling of the B and D meson spectrum in lattice QCD


  We give results for the $B$ and the $D$ meson spectrum using NRQCD on the
lattice in the quenched approximation. The masses of radially and orbitally
excited states are calculated as well as $S$-wave hyperfine and $P$-wave fine
structure. Radially excited $P$-states are observed for the first time. Radial
and orbital excitation energies match well to experiment, as does the
strange-non-strange $S$-wave splitting. We compare the light and heavy quark
mass dependence of various splittings to experiment. Our $B$-results cover a
range in lattice spacings of more than a factor of two. Our $D$-results are
from a single lattice spacing and we compare them to numbers in the literature
from finer lattices using other methods. We see no significant dependence of
physical results on the lattice spacing.
  PACS: 11.15.Ha 12.38.Gc 14.40.Lb 14.40.Nd

</DOC>
<DOC>
<DOCNO> 100657 </DOCNO>
New mathematical methods for psychophysical filtering of experimental


  The article is devoted to new mathematical methods for psychophysical
filtering of experimental data and their processing.

</DOC>
<DOC>
<DOCNO> 178697 </DOCNO>
Local and non-local equivalent potentials for p-12C scattering


  A Newton-Sabatier fixed energy inversion scheme has been used to equate
inherently non-local p-${}^{12}$C potentials at a variety of energies to pion
threshold, with exactly phase equivalent local ones. Those energy dependent
local potentials then have been recast in the form of non-local Frahn-Lemmer
interactions.

</DOC>
<DOC>
<DOCNO> 68962 </DOCNO>
Competition Between Induced Symmetry Breaking, Cooper Pairing and Chiral


  We study the competition between induced symmetry breaking (ISB),
 Cooper pairing (superconductivity) and chiral condensation at finite
non-asymptotic density. Using a quantum mechanical model studied recently by
Ilieva and Thirring, we analyze the expectation value of the fermion number
density $\la a^*a\ra$ in the presence of chemical potential and discuss
relevance of the ISB phenomenon in the model. By Bogoliubov transformation, we
obtain the ground state energy and find that a phase with both superconducting
and mean field gap is a true ground state. We also study the effective
potentials of a two-dimensional field theory model for competitions between
$\la\bar\psi\psi\ra$, $\la\psi\psi\ra$ and $\la\psi^\dagger\psi\ra$. We find
that in the regime $\mu <\mu_c$, where $\mu_c$ is found to be around $0.4 m_F$
with $m_F$ being the renormalizaton point of chiral condensate, we have a
chiral symmetry-breaking phase with almost zero fermion number density and in
the case of $\mu >\mu_c$ the system sits in the mixed phase characterized by
 $\la \psi^\dagger\psi\ra\neq 0$ and $\la \psi\psi\ra\neq 0$ as long as the
renormalization point, $M_0$, corresponding to a superconducting gap is not
zero, $M_0\neq 0$.

</DOC>
<DOC>
<DOCNO> 11405 </DOCNO>
Dynamic mechanical response of polymer networks


  The dynamic-mechanical response of flexible polymer networks is studied in
the framework of tube model, in the limit of small affine deformations, using
the approach based on Rayleighian dissipation function. The dynamic complex
modulus G* is calculated from the analysis of a network strand relaxation to
the new equilibrium conformation around the distorted primitive path. Chain
equilibration is achieved via a sliding motion of polymer segments along the
tube, eliminating the inhomogeneity of the polymer density caused by the
deformation. The characteristic relaxation time of this motion <tau> separates
the low-frequency limit of the complex modulus from the high-frequency one,
where the main role is played by chain entanglements, analogous to the rubber
plateau in melts. The dependence of storage and loss moduli, G' and G'', on
crosslink and entanglement densities gives an interpolation between polymer
melts and crosslinked networks. We discuss the experimental implications of the
rather short relaxation time and the slow square-root variation of the moduli
and the loss factor tan<delta> at higher frequencies.

</DOC>
<DOC>
<DOCNO> 68247 </DOCNO>
Bidyon or an electromagnetic model for charged particle with spin


  The general model of nonlinear electrodynamics with dyon singularities is
considered. We introduce the field configuration having two dyon singularities
with identical electric and opposite magnetic charges and we name it as bidyon.
We investigate the sum of two dyon solution as initial approximation to the
bidyon solution. We consider the case when the velocities of the dyons have
equal modules and opposite directions on a common line. It is shown that the
associated field configuration has a constant full angular momentum which is
independent of the interdyonic distance and their speed. This property permits
a consideration of this bidyon configuration as an electromagnetic model for
charged particle with spin. We discuss the possible electrodynamic world with
oscillating bidyons as particles.

</DOC>
<DOC>
<DOCNO> 101956 </DOCNO>
Wave Equations with Point Interactions in Finite Energy Space


  Given the abstract wave equation $\ddot\phi-\Delta_\alpha\phi=0$, where
$\Delta_\alpha$ is the Laplace operator with a point interaction of strength
$\alpha$, we define and study $\bar W_\alpha$, the associated wave generator in
the phase space of finite energy states. We prove the existence of the phase
flow generated by $\bar W_\alpha$, and describe its most relevant properties
with particular emphasis on the associated symplectic structure and scattering
theory

</DOC>
<DOC>
<DOCNO> 150946 </DOCNO>
On area and entropy of a black hole


  We consider a model of a black hole consisting of a number of elementary
components. Examples of such models occur in the Ashtekar's approach to
canonical Quantum Gravity and in M-theory. We show that treating the elementary
components as completely distinguishable leads to the area law for the black
hole entropy. Contrary to previous results, we show that no Bose condensation
occurs, the area has big local fluctuations and that in the framework of
canonical Quantum Gravity the area of the black hole horizon is equidistantly
quantized.

</DOC>
<DOC>
<DOCNO> 13067 </DOCNO>
Laser probing of Cooper-paired trapped atoms


  We consider a gas of trapped Cooper-paired fermionic atoms which are
manipulated by laser light. The laser induces a transition from an internal
state with large negative scattering length (superfluid) to one with weaker
interactions (normal gas). We show that the process can be used to detect the
presence of the superconducting order parameter. Also, we propose a direct way
of measuring the size of the gap in the trap. The efficiency and feasibility of
this probing method is investigated in detail in different physical situations.

</DOC>
<DOC>
<DOCNO> 117860 </DOCNO>
What can BeppoSAX tell us about short GRBs: An update from the Subsecond


  We present some statistical considerations on the BeppoSAX hunt for subsecond
GRBs at the Scientific Operation Center. Archive analysis of a BATSE/SAX
sub-sample of bursts indicates that the GRB Monitor is sensitive to short (< 2
sec) events, that are in fact about 22% of the total. The non-detection of
corresponding prompt X-ray counterparts to short bursts in the Wide Field
Cameras, in about 3 years of operations, is discussed: with present data no
implications on the X-to-gamma-ray spectra of short vs long GRBs may be
inferred. Finally, the status of searching procedures at SOC is reviewed.

</DOC>
<DOC>
<DOCNO> 99817 </DOCNO>
PT-symmetric sextic potentials


  The family of complex PT-symmetric sextic potentials is studied to show that
for various cases the system is essentially quasi-solvable and possesses real,
discrete energy eigenvalues. For a particular choice of parameters, we find
that under supersymmetric transformations the underlying potential picks up a
reflectionless part.

</DOC>
<DOC>
<DOCNO> 121737 </DOCNO>
Neutron stars in a class of non-linear relativistic models


  We introduce in this work a class of relativistic models for nuclear matter
and neutron stars which exhibits a parameterization, through mathematical
constants, of the non-linear meson-baryon couplings. For appropriate choices of
the parameters, it recovers current QHD models found in the literature: Walecka
and the Zimanyi and Moszkowski models (ZM and ZM3). For other choices of the
parameters, the new models give very interesting and new physical results.We
have obtained numerical values for the maximum mass and radius of a neutron
star sequence, red-shift, hyperon populations, radial distribution of
particles, among other relevant static properties of these stellar objects. The
phenomenology of neutron stars in ZM models is presented and compared to the
phenomenology obtained in other versions of the Walecka model. We have found
that the ZM3 model is too soft and predicts a very small maximum neutron star
mass, $\sim0.72 M_\odot$. A strong similarity between the results of ZM-like
models and those with exponential couplings is noted. Sensibility of the
results to the specific choice of the values for the binding energy and
saturation density is pointed out. Finally, we discuss the very intense scalar
condensates found in the interior of neutron stars which may lead to negative
effective masses.

</DOC>
<DOC>
<DOCNO> 71607 </DOCNO>
P-violating effects in low-energy Compton scattering


  Parity of effects induced by one loop corrections of Standard model of
 Compton scattering are considered. We note the main effects arise from W
contributions. Keeping in the mind scheme independent gauge invariance
amplitude we calculated the one spin asymmetries for the case when initial
electron is polarized and the case of circular polarized photon. They are of
order $10^{-13}$.

</DOC>
<DOC>
<DOCNO> 122974 </DOCNO>
MACHO 96-LMC-2: Lensing of a Binary Source in the LMC and Constraints on


  We present photometry and analysis of the microlensing alert MACHO 96-LMC-2.
The ~3% photometry provided by the Global Microlensing Alert Network follow--up
effort reveals a periodic modulation in the lightcurve. We attribute this to
binarity of the lensed source. Microlensing fits to a rotating binary source
magnified by a single lens converge on two minima, separated by delta chi^2 ~
1. The most significant fit X1 predicts a primary which contributes ~100% of
the light, a dark secondary, and an orbital period (T) of 9.2 days. The second
fit X2 yields a binary source with two stars of roughly equal mass and
luminosity, and T = 21.2 days.
  The lensed object appears to lie on the upper LMC main sequence. We estimate
the mass of the primary component of the binary system, M ~2 M_sun. For the
preferred model X1, we explore the range of dark companions by assuming 0.1
M_sun and 1.4 M_sun objects in models X1a and X1b, respectively. We find lens
velocities projected to the LMC in these models of v^hat_X1a = 18.3 +/- 3.1
km/s and v^hat_X1b = 188 +/- 32 k/ms. In both these cases, a likelihood
analysis suggests an LMC lens is preferred over a Galactic halo lens, although
only marginally so in model X1b. We also find v^hat_X2 = 39.6 +/- 6.1 k/ms,
where the likelihood for the lens location is strongly dominated by the LMC
disk. In all cases, the lens mass is consistent with that of an M-dwarf. The
LMC self-lensing rate contributed by 96-LMC-2 is consistent with model
self-lensing rates. (Abridged)

</DOC>
<DOC>
<DOCNO> 117502 </DOCNO>
On the optical pulsations from the Geminga pulsar


  We present a model for generation mechanisms of the optical pulsations
recently detected from the Geminga pulsar. We argue that this is just a
synchrotron radiation emitted along open magnetic field lines at altitudes of a
few light cylinder radii (which requires that Geminga is an almost aligned
rotator), where charged particles acquire non-zero pitch-angles as a result of
the cyclotron absorption of radio waves in the magnetized pair plasma. This
explains self-consistently both the lack of apparent radio emission, at least
at frequencies higher than about 100 MHz, and the optical pulsations from the
Geminga pulsar. From our model it follows that the synchrotron radiation is a
maximum in the infrared band, which suggests that Geminga should also be a
source of a pulsed infrared emission.

</DOC>
<DOC>
<DOCNO> 118014 </DOCNO>
Optical Counterparts to Damped Lyman Alpha Systems


  Previously we have shown (Maller et al, 1998) that the kinematics of Damped
Lyman Alpha Systems (DLAS) as measured by Prochaska and Wolfe (1998) can be
reproduced in a multiple disk model (MDM) if the gaseous disks are of
sufficient radial extent. Here we discuss this model's predictions for the
relationship between DLAS and Lyman break galaxies (LBGs), which we here take
to be objects at z~3 brighter than R=25.5. We expect that future observations
of the correlations between DLAS and LBGs will provide a new data set able to
discriminate between different theoretical models of the DLAS. Djorgovski
(1997) has already detected a few optical counterparts and more studies are
underway.

</DOC>
<DOC>
<DOCNO> 9852 </DOCNO>
Emergence of Quantum Chaos in Quantum Computer Core and How to Manage It


  We study the standard generic quantum computer model, which describes a
realistic isolated quantum computer with fluctuations in individual qubit
energies and residual short-range inter-qubit couplings. It is shown that in
the limit where the fluctuations and couplings are small compared to one-qubit
energy spacing the spectrum has a band structure and a renormalized Hamiltonian
is obtained which describes the eigenstate properties inside one band. The
studies are concentrated on the central band of the computer (``core'') with
the highest density of states. We show that above a critical inter-qubit
coupling strength, quantum chaos sets in, leading to quantum ergodicity of the
computer eigenstates. In this regime the ideal qubit structure disappears, the
eigenstates become complex and the operability of the computer is quickly
destroyed. We confirm that the quantum chaos border decreases only linearly
with the number of qubits n, although the spacing between multi-qubit states
drops exponentially with n. The investigation of time-evolution in the quantum
computer shows that in the quantum chaos regime, an ideal (noninteracting)
state quickly disappears and exponentially many states become mixed after a
short chaotic time scale for which the dependence on system parameters is
determined. Below the quantum chaos border an ideal state can survive for long
times and be used for computation. The results show that a broad parameter
region does exist where the efficient operation of a quantum computer is
possible.

</DOC>
<DOC>
<DOCNO> 122581 </DOCNO>
The Formal Underpinnings of the Response Functions used in X-Ray


  This work provides an in-depth mathematical description of the response
functions that are used for spatial and spectral analysis of X-ray data. The
use of such functions is well-known to anyone familiar with the analysis of
X-ray data where they may be identified with the quantities contained in the
Ancillary Response File (ARF), the Redistribution Matrix File (RMF), and the
Exposure Map. Starting from first-principles, explicit mathematical expressions
for these functions, for both imaging and dispersive modes, are arrived at in
terms of the underlying instrumental characteristics of the telescope including
the effects of pointing motion. The response functions are presented in the
context of integral equations relating the expected detector count rate to the
source spectrum incident upon the telescope. Their application to the analysis
of several source distributions is considered. These include multiple, possibly
overlapping, and spectrally distinct point sources, as well as extended
sources. Assumptions and limitations behind the usage of these functions, as
well as their practical computation are addressed.

</DOC>
<DOC>
<DOCNO> 100145 </DOCNO>
Classical and quantum dynamics of a spin-1/2


  We reply to a comment on `Semiclassical dynamics of a spin-1/2 in an
arbitrary magnetic field'.

</DOC>
<DOC>
<DOCNO> 83424 </DOCNO>
Exploring automatic word sense disambiguation with decision lists and


  The most effective paradigm for word sense disambiguation, supervised
learning, seems to be stuck because of the knowledge acquisition bottleneck. In
this paper we take an in-depth study of the performance of decision lists on
two publicly available corpora and an additional corpus automatically acquired
from the Web, using the fine-grained highly polysemous senses in WordNet.
Decision lists are shown a versatile state-of-the-art technique. The
experiments reveal, among other facts, that SemCor can be an acceptable (0.7
precision for polysemous words) starting point for an all-words system. The
results on the DSO corpus show that for some highly polysemous words 0.7
precision seems to be the current state-of-the-art limit. On the other hand,
independently constructed hand-tagged corpora are not mutually useful, and a
corpus automatically acquired from the Web is shown to fail.

</DOC>
<DOC>
<DOCNO> 68315 </DOCNO>
Minijets and Transverse Energy Flow in High Energy Collisions


  When studying the production of minijets and transverse energy flow in high
energy hadron-hadron or nucleus-nucleus collisions, two essential points have
to be taken into account. First, one has to account for the virtuality of the
colliding partons and secondly, it is important to avoid double counting, when
many links in a parton chain can be interpreted as the momentum transfer in a
hard subcollision. The Linked Dipole Chain model, introduced for low-x DIS, is
particularly suitable for a study of these problems. It describes (mini)jet
production in a kT-factorizing formalism, which includes all links in a parton
chain on an equal footing, avoiding double counting. In a ``naive'' calculation
based on integrated structure functions, the cross section blows up for small
pT, which makes it necessary to introduce a soft cutoff. In our approach we
find a dynamical suppression at low pT, which makes it possible to extrapolate
to higher energies and make more reliable predictions for RHIC and LHC.

</DOC>
<DOC>
<DOCNO> 170709 </DOCNO>
Speakable and unspeakable after John Bell


  `Philosophy' was speakable for John Bell but is not for many physicists. The
border between philosophy and physics is here illustrated through Brownian
motion and Bell experiments. `Measurement', however, was unspeakable for Bell.
His insistence that the physics of quantum measurement should not be confined
to the laboratory and that physics is concerned with the big world outside
leads us to examples from zoology, meteorology and cosmology.

</DOC>
<DOC>
<DOCNO> 10859 </DOCNO>
Statistical Mechanics of Recurrent Neural Networks II. Dynamics


  A lecture notes style review of the non-equilibrium statistical mechanics of
recurrent neural networks with discrete and continuous neurons (e.g. Ising,
graded-response, coupled-oscillators). To be published in the Handbook of
Biological Physics (North-Holland). Accompanied by a similar review (part I)
dealing with the statics.

</DOC>
<DOC>
<DOCNO> 12542 </DOCNO>
A boost to low energy nuclear reactions from preliminary elastic


  In conventional nuclear experiments a beam of accelerated nuclei collides
with a target nucleus that is surrounded by other nuclei in a molecule, in
condensed matter, or in a plasma environment. It is shown that for low
collision energies possible nuclear reactions (including deuterium fusion) are
strongly boosted by the environment. The effect originates from a chain of
preliminary three elastic collisions which transform the projectile-target
experiment into one with colliding beams. Firstly, the projectile-target pair
of nuclei undergo elastic scattering in which the projectile shares its energy
and momentum with the target nucleus. Then the projectile and target nuclei
collide with different heavy nuclei from the environment. These latter
collisions change the velocities of the target and projectile nuclei and set
them again on the collision course. Finally, the same pair of nuclei collide
inelastically, this time giving rise to the nuclear reaction. The increased
energy of the target nucleus increases the relative velocity up to sqrt 2
times, resulting in a drastic exponential increase of the probability to
penetrate the Coulomb barrier and therefore sharply increasing the likelihood
of the nuclear reaction. Applications to laser-induced fusion are discussed.

</DOC>
<DOC>
<DOCNO> 118174 </DOCNO>
Water Ice in 2060 Chiron and its Implications for Centaurs and Kuiper


  We report the detection of water ice in the Centaur 2060 Chiron, based on
near-infrared spectra (1.0 - 2.5 micron) taken with the 3.8-meter United
Kingdom Infrared Telescope (UKIRT) and the 10-meter Keck Telescope. The
appearance of this ice is correlated with the recent decline in Chiron's
cometary activity: the decrease in the coma cross-section allows previously
hidden solid-state surface features to be seen. We predict that water ice is
ubiquitous among Centaurs and Kuiper Belt objects, but its surface coverage
varies from object to object, and thus determines its detectability and the
occurrence of cometary activity.

</DOC>
<DOC>
<DOCNO> 119097 </DOCNO>
Status of HI searches for CHVCs beyond the Local Group


  Growing evidence supports the suggestion that the compact high-velocity
clouds of HI (CHVCs) are located throughout the Local Group and continue to
fuel galactic evolution. Recent distance estimates to individual objects lie in
the range 150-850 kpc, implying an HI mass range of 10^5.7 to 10^7.2 M_Sun
together with sizes ranging from 2-12 kpc, while the average linewidth is 30
km/s FWHM. It is natural to ask whether objects of this type would not already
have been seen by current blind HI surveys of the extragalactic sky. We
consider the properties of the deepest published surveys of this type and
conclude that the sensitivity and coverage have now begun to reveal the high
mass end of the distribution (M_HI >10^7 M_Sun). Achieving detection limits an
order of magnitude deeper should finally enable direct study of these systems
beyond the Local Group, or definitively rule out their existence.

</DOC>
<DOC>
<DOCNO> 102875 </DOCNO>
A signal-recovery system: asymptotic properties and construction of an


  We consider a linear sequence of `nodes', each of which can be in state 0
(`off') or 1 (`on'). Signals from outside are sent to the rightmost node and
travel instantaneously as far as possible to the left along nodes which are
`on'. These nodes are immediately switched off, and become on again after a
recovery time. The recovery times are independent exponentially distributed
random variables.
  We present properties for finite systems and use some of these properties to
construct an infinite-volume extension, with signals `coming from infinity'.
This construction is related to a question by D. Aldous and we expect that it
sheds some light on, and stimulates further investigation of, that question.

</DOC>
<DOC>
<DOCNO> 12143 </DOCNO>
Theory of STM Spectroscopy of Kondo Ions on Metal Surfaces


  The conduction electron density of states nearby a single magnetic impurity,
as measured recently by scanning tunneling microscopy (STM), is calculated. It
is shown that the Kondo effect induces a narrow Fano resonance as an intrinsic
feature in the conduction electron density of states. The line shape varies
with the distance between STM tip and impurity, in qualitative agreement with
experiments, and is sensitive to details of the band structure. For a Co
impurity the experimentally observed width and shift of the Kondo resonance are
in accordance with those obtained from a combination of band structure and
strongly correlated calculations.

</DOC>
<DOC>
<DOCNO> 122292 </DOCNO>
Optical and EUV Light Curves of Dwarf Nova Outbursts


  We combine AAVSO and VSS/RASNZ optical and Extreme Ultraviolet Explorer EUV
light curves of dwarf novae in outburst to place constraints on the nature of
dwarf nova outbursts. From the observed optical-EUV time delays of 0.75-1.5
days, we show that the propagation velocity of the dwarf nova instability
heating wave is ~ 3 km/s.

</DOC>
<DOC>
<DOCNO> 8067 </DOCNO>
Ising Model and L - Function


  The correlation functions are calculated for the two dimensional Ising model
with free boundary conditions and the two dimensional Ising model with periodic
boundary conditions.

</DOC>
<DOC>
<DOCNO> 72324 </DOCNO>
Pole Solution in Six Dimensions and Mass Hierarchy


  A solution of the 6D gravitational model, which has the pole configuration,
is found. The vacuum setting is done by the 6D Higgs potential and the solution
is for a family of the vacuum and boundary parameters. The boundary condition
is solved by the $1/k^2$-expansion (thin pole expansion) where $1/k$ is the
{\it thickness} of the pole. The obtained analytic solution is checked by the
numerical method. This is a dimensional reduction model from 6D to 4D by use of
the soliton solution (brane world). It is regarded as a higher dimensional
version of the Randall-Sundrum 5D model. The mass hierarchy is examined.
Especially the {\it geometrical see-saw} mass relation is obtained. Some
physical quantities in 4D world such as the Planck mass, the cosmological
constant, and fermion masses are focussed. Comparison with the 5D model is
made.

</DOC>
<DOC>
<DOCNO> 40257 </DOCNO>
CP-Violating MSSM Higgs Bosons in the Light of LEP 2


  In the MSSM, the CP parities of the neutral Higgs bosons may be mixed by
radiative effects induced by explicit CP violation in the third generation of
squarks. To allow for this possibility, we argue that the charged Higgs-boson
mass and tan(beta) should be used to parametrize the MSSM Higgs sector. We
introduce a new benchmark scenario of maximal CP violation appropriate for
direct searches of CP-violating MSSM Higgs bosons. We show that the bounds
established by LEP 2 on the MSSM Higgs sector may be substantially relaxed at
low and intermediate values of tan(beta) in the presence of CP violation, and
comment on possible Higgs boson signatures at LEP 2 within this framework.

</DOC>
<DOC>
<DOCNO> 118858 </DOCNO>
Local Group Dwarf Galaxies and the Star Formation Law at High Redshift


  I show how the existing observational data on Local Group dwarf galaxies can
be used to estimate the average star formation law during the first 3 Gyr of
the history of the universe. I find that the observational data are consistent
with the orthodox Schmidt law with a star formation efficiency of about 4
percent if the star formation is continuous (during the first 3 Gyr). The
efficiency is proportionally higher if most of the gas in the dwarfs was
consumed (and never replenished) in a short time interval well before the
universe turned 3 Gyr.

</DOC>
<DOC>
<DOCNO> 101064 </DOCNO>
Invariant Rings and Quasiaffine Quotients


  We study Hilbert's fourteenth problem from a geometric point of view.
Nagata's celebrated counterexample demonstrates that for an arbitrary group
action on a variety the ring of invariant functions need not be isomorphic to
the ring of functions of an affine variety. Nevertheless one can prove that
such a ring of invariants is always isomorphic to the ring of functions on a
quasi-affine variety. Conversely, for a given quasi-affine variety V there
exists always an action of the additive group on some affine variety W such
that the ring of functions of V is isomorphic to the ring of invariant
functions on W. Thus a k-algebra occurs as invariant ring for some group acting
on a k-variety iff it occurs as function ring for some quasi-affine k-variety.

</DOC>
<DOC>
<DOCNO> 84515 </DOCNO>
The nonlinear evolution of de Sitter space instabilities


  We investigate the quantum evolution of large black holes that nucleate
spontaneously in de Sitter space. By numerical computation in the s-wave and
one-loop approximations, we verify claims that such black holes can initially
"anti-evaporate" instead of shrink. We show, however, that this is a transitory
effect. It is followed by an evaporating phase, which we are able to trace
until the black holes are small enough to be treated as Schwarzschild. Under
generic perturbations, the nucleated geometry is shown to decay into a ring of
de Sitter regions connected by evaporating black holes. This confirms that de
Sitter space is globally unstable and fragments into disconnected daughter
universes.

</DOC>
<DOC>
<DOCNO> 119931 </DOCNO>
Tracing the Mass during Low-Mass Star Formation. I. Submillimeter


  We have obtained 850 and 450 micron continuum maps of 21 low mass cores with
SED's ranging from pre-protostellar to Class I (18K < Tbol < 370K), using SCUBA
at the JCMT. In this paper we present the maps, radial intensity profiles, and
photometry. Pre-protostellar cores do not have power-law intensity profiles,
whereas the intensity profiles of Class 0 and Class I sources can be fitted
with power laws over a large range of radii. A substantial number of sources
have companion sources within a few arcminutes (2 out of 5 pre-protostellar
cores, 9 out of 16 Class 0/I sources). The mean separation between sources is
10800 AU. The median separation is 18000 AU including sources without
companions as a lower limit. The mean value of the spectral index between 450
and 850 microns is 2.8 +- 0.4, with PPCs having slightly lower spectral indices
(2.5 +- 0.4). The mean mass of the sample, based on the dust emission in a 120
arcsecond aperture, is 1.1 +- 0.9 solar masses. For the sources fitted by
power-law intensity distributions (I_nu(b)/I_nu(0) = (b/b_0) ^ m), the mean
value of m is 1.52 +- 0.45 for Class 0 and I sources at 850 microns and 1.44 +-
0.25 at 450 microns. Based on a simple analysis, assuming the emission is in
the Rayleigh-Jeans limit and that T_d(r) ~ r ^ {-0.4}, these values of m
translate into power-law density distributions (n ~ r ^ {-p}) with p ~ 2.1.
However, we show that this result may be changed by more careful consideration
of effects such as beam size and shape, finite outer radii, more realistic
T_d(r), and failure of the Rayleigh-Jeans approximation.

</DOC>
<DOC>
<DOCNO> 9986 </DOCNO>
Quantum Force in Superconductor


  Transitions between states with continuous (called as classical state) and
discrete (called as quantum state) spectrum of permitted momentum values is
considered. The persistent current can exist along the ring circumference in
the quantum state in contrast to the classical state. Therefore the average
momentum can changes at the considered transitions. In order to describe the
reiterated switching into and out the quantum state an additional term is
introduced in the classical Boltzmann transport equation. The force inducing
the momentum change at the appearance of the persistent current is called as
quantum force. It is shown that dc potential difference is induced on ring
segments by the reiterated switching if the dissipation force is not
homogeneous along the ring circumference. The closing of the superconducting
state in the ring is considered as real example of the transition from
classical to quantum state

</DOC>
<DOC>
<DOCNO> 40572 </DOCNO>
Measurement of negative particle multiplicity in S-Pb collisions at 200


  A high statistics study of the negative multiplicity distribution from S-Pb
collisions at 200 GeV/c per nucleon is presented. The NA36 TPC was used to
detect charged particles; corrections are based upon the maximum entropy
method.

</DOC>
<DOC>
<DOCNO> 12540 </DOCNO>
Statistical Mechanics: A Selective Review of Two Central Issues


  I give a highly selective overview of the way statistical mechanics explains
the microscopic origins of the time asymmetric evolution of macroscopic systems
towards equilibrium and of first order phase transitions in equilibrium. These
phenomena are emergent collective properties not discernible in the behavior of
individual atoms. They are given precise and elegant mathematical formulations
when the ratio between macroscopic and microscopic scales becomes very large.

</DOC>
<DOC>
<DOCNO> 12621 </DOCNO>
Nonextensive Thermostatistical Investigation of The Blackbody Radiation


  Thermodynamical quantities of the blackbody radiation, such as free energy,
entropy, total radiation energy, specific heat are calculated within the
Tsallis thermostatistics where factorization method is incorparated. It is
shown that basic thermodynamical relation of the blackbody radiation is form
invariant with respect to nonextensivity entropic index q. Furthermore, the
nonextensive thermodynamical quantities related to the blackbody radiation is
seperately be obtained in terms of q and the standard thermodynamical
quantities of the blackbody radiation .It is indicated that the formulation may
give a way to determine the q which determines the degree of the nonextensivity
that is the one of the aims of the present study.

</DOC>
<DOC>
<DOCNO> 68265 </DOCNO>
Either neutralino dark matter or cuspy dark halos


  We show that if the neutralino in the minimal supersymmetric standard model
is the dark matter in our galaxy, there cannot be a dark matter cusp extending
to the galactic center. Conversely, if a dark matter cusp extends to the
galactic center, the neutralino cannot be the dark matter in our galaxy. We
obtain these results considering the synchrotron emission from neutralino
annihilations around the black hole at the galactic center.

</DOC>
<DOC>
<DOCNO> 169742 </DOCNO>
Motional sidebands and direct measurement of the cooling rate in the


  Resonance fluorescence of a single trapped ion is spectrally analyzed using a
heterodyne technique. Motional sidebands due to the oscillation of the ion in
the harmonic trap potential are observed in the fluorescence spectrum. From the
width of the sidebands the cooling rate is obtained and found to be in
agreement with the theoretical prediction.

</DOC>
<DOC>
<DOCNO> 100747 </DOCNO>
Mixing times for Markov chains on wreath products and related


  We develop a method for analyzing the mixing times for a quite general class
of Markov chains on the complete monomial group G \wr S_n (the wreath product
of a group G with the permutation group S_n) and a quite general class of
Markov chains on the homogeneous space (G \wr S_n) / (S_r \times S_{n - r}).
  We derive an exact formula for the L^2 distance in terms of the L^2 distances
to uniformity for closely related random walks on the symmetric groups S_j for
1 \leq j \leq n or for closely related Markov chains on the homogeneous spaces
S_{i + j} / (S_i \times S_j) for various values of i and j, respectively. Our
results are consistent with those previously known, but our method is
considerably simpler and more general.

</DOC>
<DOC>
<DOCNO> 100995 </DOCNO>
Multiple categories: the equivalence of a globular and a cubical


  We show the equivalence of two kinds of strict multiple category, namely the
well known globular omega-categories, and the cubical omega-categories with
connections.

</DOC>
<DOC>
<DOCNO> 13144 </DOCNO>
Optimization of semiconductor quantum devices by evolutionary search


  A novel simulation strategy is proposed to search for semiconductor quantum
devices which are optimized with respect to required performances. Based on
evolutionary programming, a tecnique implementing the paradigm of genetic
algorithms to more complex data structures than strings of bits, the proposed
algorithm is able to deal with quantum devices with preset non-trivial
constraints (transition energies, geometrical requirements, etc.). Therefore,
our approach allows for automatic design, thus avoiding costly by-hand
optimizations. We demonstrate the advantages of the proposed algorithm by a
relevant and non-trivial application, the optimization of a
second-harmonic-generation device working under resonance conditions.

</DOC>
<DOC>
<DOCNO> 12661 </DOCNO>
d-Wave Superconductivity Induced by Chern-Simons Term in High-$T_c$


  We show that a Chern-Simons term for a gauge field describing a fluctuation
of spins is induced by integrating out hole fields in the presence of
spin-orbit coupling which originates from a buckling of the CuO$_2$ plane.
Through the Chern-Simons term, holes behave like skyrmion excitations in a spin
system and become a superconducting state with $d_{x^2-y^2}$ symmetry after the
antiferromagnetic long-range order is destroyed.

</DOC>
<DOC>
<DOCNO> 40182 </DOCNO>
Measurement of Light-Cone Wave Functions by Diffractive Dissociation


  Diffractive dissociation of particles can be used to study their light-cone
wave function. Results from Fermilab experiment E791 for diffractive
dissociation of 500 GeV/c $\pi^-$ mesons into di-jets are presented. The
results show that the $|q\bar {q}>$ light-cone asymptotic wave function
describes the data well for $Q^2 \sim 10 ~{\rm (GeV/c)^2}$ or more. Evidence
for color transparency comes from a measurement of the $A$-dependence of the
yield of the diffractive di-jets. It is proposed to carry out similar studies
for the light-cone wave function of the photon.

</DOC>
<DOC>
<DOCNO> 99698 </DOCNO>
Reidemeister Torsion of 3-Dimensional Euler Structures with Simple


  We generalize Turaev's definition of torsion invariants of pairs (M,x), where
M is a 3-dimensional manifold and x is an Euler structure on M (a non-singular
vector field up to homotopy relative to bM and local modifications in int(M).
Namely, we allow M to have arbitrary boundary and x to have simple (convex
and/or concave) tangency circles to the boundary. We prove that Turaev's
H_1(M)-equivariance formula holds also in our generalized context. Our torsions
apply in particular to (the exterior of) pseudo-Legendrian knots (i.e. knots
transversal to a given vector field), and hence to Legendrian knots in contact
3-manifolds. We show that torsion, as an absolute invariant, contains a lifting
to pseudo-Legendrian knots of the classical Alexander invariant. We also
precisely analyze the information carried by torsion as a relative invariant of
pseudo-Legendrian knots which are framed-isotopic. Using branched standard
spines to describe vector fields we show how to explicitly invert Turaev's
reconstruction map from combinatorial to smooth Euler structures, thus making
the computation of torsions a more effective one. As an example we work out a
specific calculation.

</DOC>
<DOC>
<DOCNO> 178898 </DOCNO>
Review of existing breakup and transfer theories leading to continuum


  This is a brief review of recent experimental and theoretical works aiming at
extracting spectroscopic information from quasielasic projectile breakup
reactions at intermediate energies.

</DOC>
<DOC>
<DOCNO> 68347 </DOCNO>
Weak transition matrix elements from finite-volume correlation functions


  The two-body decay rate of a weakly decaying particle (such as the kaon) is
shown to be proportional to the square of a well-defined transition matrix
element in finite volume. Contrary to the physical amplitude, the latter can be
extracted from finite-volume correlation functions in euclidean space without
analytic continuation. The K -> pi pi transitions and other non-leptonic decays
thus become accessible to established numerical techniques in lattice QCD.

</DOC>
<DOC>
<DOCNO> 11708 </DOCNO>
Fluctuations in finite critical and turbulent systems


  We show that hyperscaling and finite-size scaling imply that the probability
distribution of the order parameter in finite size critical systems exhibit
data collapse. We consider the examples of equilibrium critical systems, and a
statistical model of ecology. We explain recent observations that the
probability distribution of turbulent power fluctuations in closed flows is the
same as that of the harmonic 2DXY model.

</DOC>
<DOC>
<DOCNO> 151403 </DOCNO>
Hamiltonian Formalism for Space-time Non-commutative Theories


  Space-time non-commutative theories are non-local in time. We develop the
Hamiltonian formalism for non-local field theories in d space-time dimensions
by considering auxiliary d+1 dimensional field theories which are local with
respect to the evolution time. The Hamiltonian path integral quantization is
considered and the Feynman rules in the Lagrangian formalism are derived. The
case of non-commutative \phi^3 theory is considered as an example.

</DOC>
<DOC>
<DOCNO> 83395 </DOCNO>
A Classification Approach to Word Prediction


  The eventual goal of a language model is to accurately predict the value of a
missing word given its context. We present an approach to word prediction that
is based on learning a representation for each word as a function of words and
linguistics predicates in its context. This approach raises a few new questions
that we address. First, in order to learn good word representations it is
necessary to use an expressive representation of the context. We present a way
that uses external knowledge to generate expressive context representations,
along with a learning method capable of handling the large number of features
generated this way that can, potentially, contribute to each prediction.
Second, since the number of words ``competing'' for each prediction is large,
there is a need to ``focus the attention'' on a smaller subset of these. We
exhibit the contribution of a ``focus of attention'' mechanism to the
performance of the word predictor. Finally, we describe a large scale
experimental study in which the approach presented is shown to yield
significant improvements in word prediction tasks.

</DOC>
<DOC>
<DOCNO> 102784 </DOCNO>
Invitation to higher local fields, Interlude: Existence theorem for


  Viewing higher local fields as ring objects in the category of iterated
pro-ind-objects, a definition of open subgroups in Milnor K-groups of the
fields is given. The self-duality of the additive group of a higher local field
is proved. By studying norm groups of cohomological objects and using
cohomological approach to higher local class field theory the existence theorem
is proved.

</DOC>
<DOC>
<DOCNO> 120489 </DOCNO>
Are "Bondi-Hoyle Wakes" detectable in clusters of galaxies?


  In clusters of galaxies, the reaction of the intracluster medium (ICM) to the
motion of the co-existing galaxies in the cluster triggers the formation of
unique features, which trace their position and motion. Galactic wakes, for
example, are an apparent result of the ICM/galaxy interactions, and they
constitute an important tool for deciphering the motion of the cluster
galaxies. In this paper we investigate whether Bondi-Hoyle accretion can create
galactic wakes by focusing the ICM behind moving galaxies. The solution of the
equations that describe this physical problem provide us with observable
quantities along the wake at any time of its lifetime. We also investigate
which are the best environmental conditions for the detectability of such
structures in the X-ray images of clusters of galaxies. We find that
significant Bondi-Hoyle wakes can only be formed in low temperature clusters,
and that they are more pronounced behind slow-moving, relatively massive
galaxies. The scale length of these elongated structures is not very large: in
the most favourable conditions a Bondi-Hoyle wake in a cluster at the redshift
of z=0.05 is 12 arcsec long. However, the wake's X-ray emission is noticeably
strong: the X-ray flux can reach ~30 times the flux of the surrounding medium.
Such features will be easily detectable in Chandra's and XMM-Newton's X-ray
images of nearby, relatively poor clusters of galaxies.

</DOC>
<DOC>
<DOCNO> 69915 </DOCNO>
Quantum deletion is possible via a partial randomization procedure


  An alternative kind of deleting/erasing operation is introduced which differs
from the commonly used {\it controlled-not} (C-not) conditional logical
operation $-$to flip to a standard, `zero' value the (classical or quantum)
state of the last copy in a chain, in a deletion process. It is completely
reversible, in the classical case, possessing a most natural cloning operation
counterpart. We call this deleting procedure R-deletion since, in a way, it can
be viewed as a `randomization' of the standard C-not operator. It has the
remarkable property of by-passing in a simple manner the `impossibility of
deletion of a quantum state' principle, put forward by Pati and Braunstein
recently \cite{pbn1}.

</DOC>
<DOC>
<DOCNO> 101801 </DOCNO>
Levi foliations in pseudoconvex boundaries and vector fields that


  Boas and Straube proved a general sufficient condition for global regularity
of the d-bar Neumann problem in terms of families of vector fields that commute
approximately with d-bar. In this paper, we study the existence of these vector
fields on a compact subset of the boundary whose interior is foliated by
complex manifolds. This question turns out to be closely related to properties
of interest from the point of view of foliation theory.

</DOC>
<DOC>
<DOCNO> 119685 </DOCNO>
A Glitch in an Anomalous X-ray Pulsar


  We report the detection of a sudden spin-up of the 11 s anomalous X-ray
pulsar 1RXS J170849.0-4000910 in regular timing observations made with the
Rossi X-ray Timing Explorer. The event, which occurred between MJD 51446 (1999
September 25) and 51472 (1999 October 21), is well characterized by an increase
in the rotational frequency of magnitude (Delta nu / nu) = (6.2 +/- 0.3) x
10^-7 and an increase in the rate of spin down (Delta \dot\nu / \dot\nu) =
(1.38 +/- 0.25) x 10^-2. These values are very similar to those of glitches
observed in the Vela radio pulsar and other young radio pulsars. The event
therefore suggests that the internal structure of this anomalous X-ray pulsar
is similar to those of the radio pulsars. In particular, it implies that the
fractional moment of inertia in neutron superfluid that is not corotating with
the crust is >= 1 %. The detection of a glitch in this anomalous X-ray pulsar
constrains models for the origin of glitches in neutron stars. Most notably, it
challenges models that preclude glitches in long-period pulsars, and, under the
magnetar hypothesis, suggests that large glitches can occur in hot neutron
stars. The glitch is consistent with the predictions of the magnetar model for
anomalous X-ray pulsars, but accretion-powered scenarios cannot be excluded
using our observations alone.

</DOC>
<DOC>
<DOCNO> 119969 </DOCNO>
Removing radio interference from contaminated astronomical spectra using


  The growing level of radio frequency interference (RFI) is a recognized
problem for research in radio astronomy. This paper describes an intuitive but
powerful RFI cancellation technique that is suitable for radio spectroscopy
where time-averages are recorded. An RFI ``reference signal,'' is constructed
from the cross power spectrum of the signals from the two polarizations of a
reference horn pointed at the source of the RFI signal. The RFI signal paths
obey simple phase and amplitude closure relations, which allows computation of
the RFI contamination in the astronomical data and the corrections to be
applied to the astronomical spectra.
  Since the method is immune to the effects of multipath scattering in both the
astronomy and reference signal channels, ``clean copies'' of the RFI signal are
not required.
  The method could be generalized (1) to interferometer arrays, (2) to correct
for scattered solar radiation that causes spectral ``standing waves'' in
single-dish spectroscopy, and (3) to pulsar survey and timing applications
where a digital correlator plays an important role in broadband pulse
dedispersion.
  Future large radio telescopes, such as the proposed LOFAR and SKA arrays,
will require a high degree of RFI suppression and could implement the technique
proposed here with the benefit of faster electronics, greater digital precision
and higher data rates.

</DOC>
<DOC>
<DOCNO> 8038 </DOCNO>
Optimizing Traffic in Virtual and Real Space


  We show how optimization methods from economics known as portfolio strategies
can be used for minimizing download times in the Internet and travel times in
freeway traffic. While for Internet traffic, there is an optimal restart
frequency for requesting data, freeway traffic can be optimized by a small
percentage of vehicles coming from on-ramps. Interestingly, the portfolio
strategies can decrease the average waiting or travel times, respectively, as
well as their standard deviation (``risk''). In general, portfolio strategies
are applicable to systems, in which the distribution of the quantity to be
optimized is broad.

</DOC>
<DOC>
<DOCNO> 151281 </DOCNO>
N=1 Supersymmetric Renormalization Group Flows from IIB Supergravity


  We consider N=1 supersymmetric renormalization group flows of N=4 Yang-Mills
theory from the perspective of ten-dimensional IIB supergravity. We explicitly
construct the complete ten-dimensional lift of the flow in which exactly one
chiral superfield becomes massive (the LS flow). We also examine the
ten-dimensional metric and dilaton configurations for the ``super-QCD'' flow
(the GPPZ flow) in which all chiral superfields become massive. We show that
the latter flow generically gives rise to a dielectric 7-brane in the
infra-red, but the solution contains a singularity that may be interpreted as a
``duality averaged'' ring distribution of 5-branes wrapped on S^2. At special
values of the parameters the singularity simplifies to a pair of S-dual branes
with (p,q) charge (1,\pm 1).

</DOC>
<DOC>
<DOCNO> 121541 </DOCNO>
A simple model of the hierarchical formation of galaxies


  We develop a simple, fast and predictive model of the hierarchical formation
of galaxies which is in quantitative agreement with observations. Comparing
simulations with observations we place constraints on the density of the
universe and on the power spectrum of density fluctuations.

</DOC>
<DOC>
<DOCNO> 13831 </DOCNO>
A Free Field Representation of the Osp(2|2) current algebra at level


  The Osp(2|2) current algebra at level k=-2 is known to describe the IR fixed
point of 2D Dirac fermions, subject to a random SU(2) gauge potential. We show
that this theory has a simple free-field representation in terms of a compact,
and a non-compact free scalar field, as well as a free fermionic ghost, at
c=-2. The fermionic twist fields are crucial for the construction. The
logarithmic current-algebra primary field with vanishing scaling dimension,
transforming in an indecomposable representation, appears as a consequence of
familiar logarithmic operators at c=-2.

</DOC>
<DOC>
<DOCNO> 13231 </DOCNO>
Master Equation for Electromagnetic Dissipation and Decoherence of


  We set up a forward--backward path integral for a point particle in a bath of
photons to derive a master equation for the density matrix which describes
electromagnetic dissipation and decoherence. As an application, we recalculate
the Weisskopf-Wigner formula for the natural line width of an atomic state at
zero temperature and find, in addition, the temperature broadening caused by
the decoherence term.

</DOC>
<DOC>
<DOCNO> 11447 </DOCNO>
Noisy Monte Carlo revisited


  We present an exact Monte Carlo algorithm designed to sample theories where
the energy is a sum of many couplings of decreasing strength. Our algorithm,
simplified from that of L. Lin et al. hep-lat/9905033, avoids the computation
of almost all non-leading terms. We illustrate its use by simulating SU(2)
lattice gauge theory with a 5-loop action, and discuss further applications to
full QCD.

</DOC>
<DOC>
<DOCNO> 8910 </DOCNO>
Two-magnon Raman scattering in insulating cuprates: Modifications of the


  Calculations of Raman scattering intensities in spin 1/2 square-lattice
Heisenberg model, using the Fleury-Loudon-Elliott theory, have so far been
unable to describe the broad line shape and asymmetry of the two magnon peak
found experimentally in the cuprate materials. Even more notably, the
polarization selection rules are violated with respect to the
Fleury-Loudon-Elliott theory. There is comparable scattering in $B_{1g}$ and
$A_{1g}$ geometries, whereas the theory would predict scattering in only
$B_{1g}$ geometry. We review various suggestions for this discrepency and
suggest that at least part of the problem can be addressed by modifying the
effective Raman Hamiltonian, allowing for two-magnon states with arbitrary
total momentum. Such an approach based on the Sawatzsky-Lorenzana theory of
optical absorption assumes an important role of phonons as momentum sinks. It
leaves the low energy physics of the Heisenberg model unchanged but
substantially alters the Raman line-shape and selection rules, bringing the
results closer to experiments.

</DOC>
<DOC>
<DOCNO> 170628 </DOCNO>
Fidelity of a t-error correcting quantum code with more than t errors


  It is important to study the behavior of a t-error correcting quantum code
when the number of errors is greater than t, because it is likely that there
are also small errors besides t large correctable errors. We give a lower bound
for the fidelity of a t-error correcting stabilizer code over a general
memoryless channel, allowing more than t errors. We also show that the fidelity
can be made arbitrary close to 1 by increasing the code length.

</DOC>
<DOC>
<DOCNO> 68318 </DOCNO>
Self-energy O(alpha^2) correction to the positronium decay rate


  Self-energy corrections of order O(alpha^2) to the parapositronium and
orthopositronium decay rates are calculated. Numerical values of the
corresponding coefficients are B_p=-3.74, B_o=2.02.

</DOC>
<DOC>
<DOCNO> 121538 </DOCNO>
Gravitational Lensing by Galaxy Groups in the Hubble Deep Field


  We investigate strong lensing of galaxies in the Hubble Deep Field by
foreground groups and clusters of galaxies with masses from $10^{13}$ to
$10^{15} \MSun$. Over this mass range, groups with the profile of Navarro,
Frenk, & White (1995) are less efficient than singular isothermal spheres at
producing multiple images of galaxies, by factors of $5 \times 10^{- 2}$ to
$10^{- 3}$. This difference highlights the sensitivity of the lensing cross
section to the central density profile. Nonetheless, with either profile we
find that the expected number of galaxies lensed by groups in the Hubble Deep
Field is at most $\lesssim 1$, consistent with the lack of clearly identified
group lens systems.

</DOC>
<DOC>
<DOCNO> 12794 </DOCNO>
Cellular Dynamical Mean Field Approach to Strongly Correlated Systems


  We propose a cellular version of dynamical-mean field theory which gives a
natural generalization of its original single-site construction and is
formulated in different sets of variables. We show how non-orthogonality of the
tight-binding basis sets enters the problem and prove that the resulting
equations lead to manifestly causal self energies.

</DOC>
<DOC>
<DOCNO> 116670 </DOCNO>
Work performed by a Classical-"reversible"-Carnot cycle: Raising's


  The expansions or the compressions of the ideal gas in the quasi-static
Carnot cycle, can be performed (on adiabatic or isothermal way) by slowly
increasing or decreasing the external pressure by means of small weights acting
on the piston of the vessel containing the gas. We call them shortly the
``driving weights'' (dw). Let N be their number, a large one.
  To determine the work performed by the ideal gas in the cycle the ``driving
weights'' must be handled carefully. If we let them move on-off the piston only
horizontally, their vertical motions will be due only to the gas. Here we show
that, at the end, while some of them will have moved down (will have negative
raising) the remaining ones (the majority) will have moved up (will have
positive raising) so that the total work performed by the ideal gas equals the
total variation of the gravitational potential energy of the ``driving
weghts''.
  The cycle is performed in 2N time-steps. For each step t_i, with i in
1,..,2N, we give H(t_i), and DH(t_{i-1},t_i), respectively the height and the
raising of the piston. Moreover the overall raising of the individual dw's
(i.e. h_k, with k in 1...N), and their distribution are given in simple,
general cases. The efficiency and the dissipated work are also evaluated.
  This paper is aimed at imparting a deeper understanding of the ideal Carnot
Engine and may also be useful as a segment in a didactic path on elementary
calculus and statistics.

</DOC>
<DOC>
<DOCNO> 152260 </DOCNO>
Non-abelian Born-Infeld and kappa-symmetry


  We define an iterative procedure to obtain a non-abelian generalization of
the Born-Infeld action. This construction is made possible by the use of the
severe restrictions imposed by kappa-symmetry. In this paper we will present
all bosonic terms in the action up to terms quartic in the Yang-Mills field
strength and all fermion bilinear terms up to terms cubic in the field
strength. Already at this order the fermionic terms do not satisfy the
symmetric trace-prescription.

</DOC>
<DOC>
<DOCNO> 12650 </DOCNO>
Memory Effects and Heat Transport in One-dimensional Insulators


  We study the dynamical correlation functions and heat conduction for the
simplest model of quasi one-dimensional (1d) dielectric crystal i.e. a chain of
classical particles coupled by quadratic and cubic intersite potential. Even in
the weakly nonlinear regime, numerical simulation on long enough chains reveal
sizeable deviations from the perturbative results in the form of a slower decay
of correlations in equilibrium. Their origin can be traced back to the subtle
nonlinear effects described by mode-coupling theories. Measures of thermal
conductivity with nonequilibrium molecular-dynamics method confirm the
relevance of such effects for low-dimensional lattices even at very low
temperatures.

</DOC>
<DOC>
<DOCNO> 8801 </DOCNO>
Zigzag Charge Ordering in alpha'-NaV2O5


  23Na NMR spectrum measurements in alpha'-NaV2O5 with a single- crystalline
sample are reported. In the charge-ordered phase, the number of inequivalent Na
sites observed is more than that expected from the low-temperature structures
of space group Fmm2 reported so far. This disagreement indicates that the real
structure including both atomic displacement and charge disproportionation is
of lower symmetry. It is suggested that zigzag ordering is the most probable.
The temperature variation of the NMR spectra near the transition temperature is
incompatible with that of second-order transitions. It is thus concluded that
the charge ordering transition is first-order.

</DOC>
<DOC>
<DOCNO> 118152 </DOCNO>
Extragalactic Globular Cluster Systems: A new Perspective on Galaxy


  We present an overview of observational progress in the study of
extragalactic globular cluster systems. Globular clusters turn out to be
excellent tracers not only for the star-formation histories in galaxies, but
also for kinematics at large galactocentric radii. Their properties can be used
to efficiently constrain galaxy formation and evolution. After a brief
introduction of the current methods and futures perspectives, we summarize the
knowledge gained in various areas of galaxy research through the study of
globular clusters. In particular, we address the star-formation histories of
early-type galaxies; globular cluster population in late-type galaxies and
their link to early-type galaxies; star and cluster formation during mergers
and violent interactions; and the kinematics at large radii in early-type
galaxies. The different points are reviewed within the context of galaxy
formation and evolution.
  Finally, we revisit the globular cluster luminosity function as a distance
indicator. Despite its low popularity in the literature, we demonstrate that it
ranks among one of the most precise distance indicators to early-type galaxies,
provided that it is applied properly.

</DOC>
<DOC>
<DOCNO> 150412 </DOCNO>
Super-D0-branes at the endpoints of fundamental superstring: an example


  We present a supersymmetric action functional for the coupled system of an
open fundamental superstring and super-D0-branes attached to (identified with)
the string endpoints. As a preliminary step the geometrical actions for a free
super-D0-brane and a free type IIA superstring have been built. The pure
bosonic limits of the action for the coupled system and of the equations of
motion are discussed in some detail.

</DOC>
<DOC>
<DOCNO> 72257 </DOCNO>
Production of 3pi0 and eta 2pi0 from pi-p Collision in GAMS Experiment


  The data on the pi- p --> M0 n, with M0 = pi0 pi0 pi0 or pi0 pi0 eta obtained
in the GAMS experiment may be useful to study the sigma(400--700) and a_1^chi
(1000), which can be taken as chiral partners of pi and rho, respectively. A
preliminary analysis for 3pi0 invariant mass spectra gives a support for the
assumed a_1^chi with a mass of 930 MeV and Gamma = 170 MeV.

</DOC>
<DOC>
<DOCNO> 13460 </DOCNO>
Thermodynamics of trapped interacting bosons in one dimension


  On the basis of Bethe ansatz solution of bosons with delta-function
interaction in a one-dimensional potential well, the thermodynamics equilibrium
of the system in finite temperature is studied by using the strategy of Yang
and Yang. The thermodynamics quantities, such as specific heat etc. are
obtained for the cases of strong coupling limit and weak coupling limit
respectively.

</DOC>
<DOC>
<DOCNO> 8070 </DOCNO>
Iterative algorithm versus analytic solutions of the parametrically


  We consider the Brownian motion of a quantum mechanical particle in a
one-dimensional parabolic potential with periodically modulated curvature under
the influence of a thermal heat bath. Analytic expressions for the
time-dependent position and momentum variances are compared with results of an
iterative algorithm, the so-called quasiadiabatic propagator path integral
algorithm (QUAPI). We obtain good agreement over an extended range of
parameters for this spatially continuous quantum system. These findings
indicate the reliability of the algorithm also in cases for which analytic
results may not be available a priori.

</DOC>
<DOC>
<DOCNO> 84705 </DOCNO>
Divergence of a quantum thermal state on Kerr space-time


  We present a simple proof, using the conservation equations, that any quantum
stress tensor on Kerr space-time which is isotropic in a frame which rotates
rigidly with the angular velocity of the event horizon must be divergent at the
velocity of light surface. We comment on our result in the light of the absence
of a `true Hartle-Hawking' vacuum for Kerr.

</DOC>
<DOC>
<DOCNO> 116482 </DOCNO>
Tumour Therapy with Particle Beams


  Photons are exponentially attenuated in matter producing high doses close to
the surface. Therefore they are not well suited for the treatment of deep
seated tumours. Charged particles, in contrast, exhibit a sharp increase of
ionisation density close to the end of their range, the so-called Bragg-peak.
The depth of the Bragg-peak can be adjusted by varying the particle's energy.
In parallel with the large energy deposit the increase in biological
effectiveness for cell killing at the end of the range provides an ideal
scalpel for the surgeon effectively without touching the surface tissue.
Consequently proton therapy has gained a lot of ground for treating well
localized tumours. Even superior still are heavy ions, where the ionisation
pattern is increased by the square of their charge.

</DOC>
<DOC>
<DOCNO> 84550 </DOCNO>
Another exact inflationary solution


  A new closed-form inflationary solution is given for a hyperbolic interaction
potential. The method used to arrive at this solution is outlined as it appears
possible to generate additional sets of equations which satisfy the model. In
addition a new form of decaying cosmological constant is presented.

</DOC>
<DOC>
<DOCNO> 83450 </DOCNO>
Small Maximal Independent Sets and Faster Exact Graph Coloring


  We show that, for any n-vertex graph G and integer parameter k, there are at
most 3^{4k-n}4^{n-3k} maximal independent sets I \subset G with |I| <= k, and
that all such sets can be listed in time O(3^{4k-n} 4^{n-3k}). These bounds are
tight when n/4 <= k <= n/3. As a consequence, we show how to compute the exact
chromatic number of a graph in time O((4/3 + 3^{4/3}/4)^n) ~= 2.4150^n,
improving a previous O((1+3^{1/3})^n) ~= 2.4422^n algorithm of Lawler (1976).

</DOC>
<DOC>
<DOCNO> 120827 </DOCNO>
Stromgren Photometry from z=0 to z~1. The Method


  We use rest-frame Stromgren photometry to observe clusters of galaxies in a
self-consistent manner from z=0 to z=0.8. Stromgren photometry of galaxies is
an efficient compromise between standard broad-band photometry and
spectroscopy, in the sense that it is more sensitive to subtle variations in
spectral energy distributions than the former, yet much less time-consuming
than the latter. Principal Component Analysis (PCA) is used to extract maximum
information from the Stromgren data. By calibrating the Principal Components
using well-studied galaxies (and stellar population models), we develop a
purely empirical method to detect, and subsequently classify, cluster galaxies
at all redshifts smaller than 0.8. Interlopers are discarded with unprecedented
efficiency (up to 100%). The first Principal Component essentially reproduces
the Hubble Sequence, and can thus be used to determine the global star
formation history of cluster members. The (PC2, PC3) plane allows us to
identify Seyfert galaxies (and distinguish them from starbursts) based on
photometric colors alone. In the case of E/S0 galaxies with known redshift, we
are able to resolve the age-dust- metallicity degeneracy, albeit at the
accuracy limit of our present observations. This technique will allow us to
probe galaxy clusters well beyond their cores and to fainter magnitudes than
spectroscopy can achieve. We are able to directly compare these data over the
entire redshift range without a priori assumptions because our observations do
not require k-corrections. The compilation of such data for different cluster
types over a wide redshift range is likely to set important constraints on the
evolution of galaxies and on the clustering process.

</DOC>
<DOC>
<DOCNO> 12739 </DOCNO>
Two-Dimensional Nature of Four-Layer Superconductors by Inequivalent


  The magnetization of the four-layer superconductor
CuBa_{2}Ca_{3}Cu_4O_{12-\delta} with T_c\simeq117 K is presented. The
high-field magnetization around T_c(H) follows the exact two-dimensional
scaling function given by Te\v{s}anovi\'{c} and Andreev. This feature is
contrary to the inference that the interlayer coupling becomes strong if the
number of CuO_2 planes in a unit cell increases. Also, the fluctuation-induced
susceptibility in the low-field region was analyzed by using the modified
Lawrence-Doniach model. The effective number of independently fluctuating CuO_2
layers per unit cell, g_{\rm eff}, turned out to be \simeq 2 rather than 4,
which indicated that two among the four CuO_2 layers were in states far from
their optimal doping levels. This result could explain why
CuBa_{2}Ca_{3}Cu_4O_{12-\delta} shows two-dimensional behavior.

</DOC>
<DOC>
<DOCNO> 121905 </DOCNO>
Chandra Observations of the X-ray Narrow-Line Region in NGC 4151


  We present the first high-resolution X-ray spectrum of the Seyfert 1.5 galaxy
NGC 4151. Observations with the Chandra High Energy Transmission Grating
Spectrometer reveal a spectrum dominated by narrow emission lines from a
spatially resolved (1.6 kpc), highly ionized nebula. The X-ray narrow-line
region is composite, consisting of both photoionized and collisionally ionized
components. The X-ray emission lines have similar velocities, widths, and
spatial extent to the optical emission lines, showing that they arise in the
same region. The clouds in the narrow-line region must contain a large range of
ionization states in order to explain both the optical and X-ray photoionized
emission. Chandra data give the first direct evidence of X-ray line emission
from a hot plasma (T~1e7 K) which may provide pressure confinement for the
cooler (T=3e4 K) photoionized clouds.

</DOC>
<DOC>
<DOCNO> 170140 </DOCNO>
A method of enciphering quantum states


  In this paper, we propose a method of enciphering quantum states of two-state
systems (qubits) for sending them in secrecy without entangled qubits shared by
two legitimate users (Alice and Bob). This method has the following two
properties. First, even if an eavesdropper (Eve) steals qubits, she can extract
information from them with certain probability at most. Second, Alice and Bob
can confirm that the qubits are transmitted between them correctly by measuring
a signature. If Eve measures m qubits one by one from n enciphered qubits and
sends alternative ones (the Intercept/Resend attack), a probability that Alice
and Bob do not notice Eve's action is equal to (3/4)^m or less. Passwords for
decryption and the signature are given by classical binary strings and they are
disclosed through a public channel. Enciphering classical information by this
method is equivalent to the one-time pad method with distributing a classical
key (random binary string) by the BB84 protocol. If Eve takes away qubits,
Alice and Bob lose the original quantum information. If we apply our method to
a state in iteration, Eve's success probability decreases exponentially. We
cannot examine security against the case that Eve makes an attack with using
entanglement. This remains to be solved in the future.

</DOC>
<DOC>
<DOCNO> 170218 </DOCNO>
Decoherence and the rate of entropy production in chaotic quantum


  We show that for an open quantum system which is classically chaotic (a
quartic double well with harmonic driving coupled to a sea of harmonic
oscillators) the rate of entropy production has, as a function of time, two
relevant regimes: For short times it is proportional to the diffusion
coefficient (fixed by the system--environment coupling strength). For longer
times (but before equilibration) there is a regime where the entropy production
rate is fixed by the Lyapunov exponent. The nature of the transition time
between both regimes is investigated.

</DOC>
<DOC>
<DOCNO> 40036 </DOCNO>
New Results on Vector Meson Production at HERA


  New results on elastic (exclusive) production of vector mesons are presented,
mainly on J/\psi and phi mesons with emphasis on an interpretation of the data
within pQCD.

</DOC>
<DOC>
<DOCNO> 9765 </DOCNO>
Scaling laws and vortex profiles in 2D decaying turbulence


  We use high resolution numerical simulations over several hundred of turnover
times to study the influence of small scale dissipation onto vortex statistics
in 2D decaying turbulence. A self-similar scaling regime is detected when the
scaling laws are expressed in units of mean vorticity and integral scale, as
predicted by Carnevale et al., and it is observed that viscous effects spoil
this scaling regime. This scaling regime shows some trends toward that of the
Kirchhoff model, for which a recent theory predicts a decay exponent $\xi=1$.
In terms of scaled variables, the vortices have a similar profile close to a
Fermi-Dirac distribution.

</DOC>
<DOC>
<DOCNO> 117313 </DOCNO>
Monte Carlo methods: Application to hydrogen gas and hard spheres


  Quantum Monte Carlo (QMC) methods can very accurately compute ground state
properties of quantum systems. We applied these methods to a system of boson
hard spheres to get exact, infinite system size results for the ground state at
several densities.
 Variational Monte Carlo (VMC) requires optimizing a parameterized wave
function to find the minimum energy. We examine several techniques for
optimizing VMC wave functions, focusing on the ability to optimize parameters
appearing in the Slater determinant.
 The kinds of problems that can be simulated with Monte Carlo methods are
expanded through the development of new algorithms for combining a QMC
simulation of the electrons with a classical Monte Carlo simulation for the
nuclei, which we call Coupled Electronic-Ionic Monte Carlo (CEIMC). The new
CEIMC method is applied to a system of molecular hydrogen at temperatures
ranging from 2800K to 4500K and densities from 0.25 to 0.46 g/cm**3.
 The challenges in constructing an efficient CEIMC simulation center mostly
around the noisy results generated from the QMC computations of the electronic
energy. The penalty method is a modification of the Metropolis method that can
tolerate noise. An improved correlated sampling method, the two-sided energy
difference method, is also presented as a method for reducing the noise.

</DOC>
<DOC>
<DOCNO> 150754 </DOCNO>
Diagrams of Noncommutative Phi-Three Theory from String Theory


  Starting from tree and one-loop tachyon amplitudes of open string theory in
the presence of a constant B-field, we explore two problems. First we show that
in the noncommutative field theory limit the amplitudes reduce to tree and
one-loop diagrams of the noncommutative phi-three theory. Next, we check
factorization of the one-loop amplitudes in the long cylinder limit.

</DOC>
<DOC>
<DOCNO> 121732 </DOCNO>
Biconical Outflow in the Seyfert Galaxy NGC 2992


  We report on a detailed kinematic study of the galactic-scale outflow in the
Seyfert galaxy NGC 2992. The TAURUS-2 Imaging Fabry-Perot Interferometer was
used on the Anglo-Australian 3.9-m telescope to derive the two-dimensional
velocity field of the Halpha-emitting gas over the central arcminute of NGC
2992. The complete two-dimensional coverage of the data combined with simple
kinematic models of rotating axisymmetric disks allows us to differentiate the
outflowing material from the line-emitting material associated with the
galactic disk. The kinematics of the disk component out to R = 3.0 kpc are well
modeled by pure circular rotation. The outflow component is distributed into
two wide cones with opening angle of 125 -- 135 degrees and extending 2.8 kpc
(18") on both sides of the nucleus at nearly right angles to the disk kinematic
major axis. The outflow on the SE side of the nucleus is made of two distinct
kinematic components interpreted as the front and back walls of a cone. The
azimuthal velocity gradient in the back-wall component reflects residual
rotational motion which indicates either that the outflowing material was
lifted from the disk or that the underlying galactic disk is contributing
slightly to this component. A single outflow component is detected in the NW
cone. The most likely energy source for this outflow is a hot bipolar thermal
wind powered on sub-kpc scale by the AGN and diverted along the galaxy minor
axis by the pressure gradient of the ISM in the host galaxy. The data are not
consistent with a starburst-driven wind or a collimated outflow powered by
radio jets. (abridged)

</DOC>
<DOC>
<DOCNO> 122054 </DOCNO>
The rotation curve of spiral galaxies and its cosmological implications


  We review the topic of rotation curves of spiral galaxies emphasizing the
standard interpretation as evidence for the existence of dark matter halos.
Galaxies other than spirals and late-type dwarfs may also possess great amounts
of dark matter, and therefore ellipticals, dwarf spirals, lenticulars and polar
ring galaxies are also considered. Furthermore, other methods for determining
galactic dark matter, such as those provided by binaries, satellites or
globular clusters, have to be included. Cold dark matter hierarchical models
constitute the standard way to explain rotation curves, and thus the problem
becomes just one aspect of a more general theory explaining structure and
galaxy formation. Alternative theories also are included. In the magnetic
model, rotation curves could also be a particular aspect of the whole history
of cosmic magnetism during different epochs of the Universe. Modifications of
Newtonian Dynamics provide another interesting possibility which is discussed
here.

</DOC>
<DOC>
<DOCNO> 151784 </DOCNO>
Magnetic Moments of Branes and Giant Gravitons


  We study the magnetic analogue of Myers' Dielectric Effect and, in some
cases, relate it to the blowing up of particles into branes, first investigated
by Greevy, Susskind and Toumbas. We show that $D0$ branes or gravitons in M
theory, moving in a magnetic four-form field strength background expand into a
non-commutative two sphere. Both examples of constant magnetic field and
non-constant fields in curved backgrounds generated by branes are considered.
We find, in all cases, another solution, consisting of a two-brane wrapping a
classical two-sphere, which has all the quantum numbers of the $D0$ branes.
Motivated by this, we investigate the blowing up of gravitons into branes in
backgrounds different from $AdS_m \times S^n$. We find the phenomenon is quite
general. In many cases with less or even no supersymmetry we find a brane
configuration which has the same quantum numbers and the same energy as a
massless particle in supergravity.

</DOC>
<DOC>
<DOCNO> 71818 </DOCNO>
Probing the violation of equivalence principle at a muon storage ring


  We examine the possible tests of violation of the gravitational equivalence
principle (VEP) at a muon storage ring via neutrino oscillation experiments. If
the gravitational interactions of the neutrinos are not diagonal in the flavour
basis and the gravitational interaction eigenstates have different couplings to
the gravitational field, this leads to the neutrino oscillation. If one starts
with $\mu ^+$ beam then appearance of $\tau ^\pm$, $e ^+$ and $\mu ^-$ in the
final state are the signals for neutrino oscillation. We have estimated the
number of $\mu ^-$ events in this scenario in $\nu_\mu -N$ deep inelastic
scattering. Final state lepton energy distribution can be used to distinguish
the VEP scenario from the others. A large area of VEP parameter space can be
explored at a future muon storage ring facility with moderate beam energy.

</DOC>
<DOC>
<DOCNO> 14076 </DOCNO>
The price dynamics of common trading strategies


  A deterministic trading strategy can be regarded as a signal processing
element that uses external information and past prices as inputs and
incorporates them into future prices. This paper uses a market maker based
method of price formation to study the price dynamics induced by several
commonly used financial trading strategies, showing how they amplify noise,
induce structure in prices, and cause phenomena such as excess and clustered
volatility.

</DOC>
<DOC>
<DOCNO> 150818 </DOCNO>
Open String and Morita Equivalence of the Dirac-Born-Infeld Action with


  Based on the canonical quantization of open strings ending on D-branes with a
background B field, we construct the open string propagator. We demonstrate the
relation between the T duality of the underlying string theory and the Morita
equivalence of the interpolating general Dirac-Born-Infeld theory on a
noncommutative torus in the nonzero modulus \Phi sector. The general
noncommutative Dirac-Born-Infeld action with the Wess-Zumino terms expressed by
the background R-R fields is shown to be Morita invariant.

</DOC>
<DOC>
<DOCNO> 14108 </DOCNO>
Theory of Dynamic Stripe Induced Superconductivity


  Since the recently reported giant isotope effect on T* [1] could be
consistently explained within an anharmonic spin-charge-phonon interaction
model, we consider here the role played by stripe formation on the
superconducting properties within the same model. This is a two-component
scenario and we recast its basic elements into a BCS effective Hamiltonian. We
find that the stripe formation is vital to high-Tc superconductivity since it
provides the glue between the two components to enhance Tc to the unexpectedly
large values observed experimentally.

</DOC>
<DOC>
<DOCNO> 178888 </DOCNO>
Enhanced Strange Particle Yields - Signal of a Phase of Massless


  The yields of strange particles are calculated with the UrQMD model for
p,Pb(158 AGeV)Pb collisions and compared to experimental data. The yields are
enhanced in central collisions if compared to proton induced or peripheral
Pb+Pb collisions. The enhancement is due to secondary interactions.
Nevertheless, only a reduction of the quark masses or equivalently an increase
of the string tension provides an adequate description of the large observed
enhancement factors (WA97 and NA49). Furthermore, the yields of unstable
strange resonances as the Lambda_star(1520) resonance or the phi meson are
considerably affected by hadronic rescattering of the decay products.

</DOC>
<DOC>
<DOCNO> 80787 </DOCNO>
On the Non-Abelian Stokes Theorem


  We present the non-Abelian Stokes theorem for the Wilson loop in various
forms and discuss its meaning. Its validity has been recently questioned by
Faber, Ivanov, Troitskaya and Zach. We demonstrate that all points of their
criticism are based on mistakes in mathematics. Finally, we derive a variant of
our formula for the Wilson loop in lattice regularization.

</DOC>
<DOC>
<DOCNO> 12399 </DOCNO>
Mixing of magnetic and phononic excitations in incommensurate


  We analyze the excitation spectra of a spin-phonon coupled chain in the
presence of a soliton. This is taken as a microscopic model of a Spin-Peierls
material placed in a high magnetic field. We show, by using a semiclassical
approximation in the bosonized representation of the spins that a trapped
magnetic state obtained in the adiabatic approximation is destroyed by
dynamical phonons. Low energy states are phonons trapped by the soliton. When
the magnetic gap is smaller than the phonon frequencies the only low energy
state is a mixed magneto-phonon state with the energy of the gap. We emphasize
that our results are relevant for the Raman spectra of the inorganic
Spin-Peierls material CuGeO$_3$.

</DOC>
<DOC>
<DOCNO> 40251 </DOCNO>
The Search for the QGP: A Critical Appraisal


  Over the past 15 years, an extensive program of high energy nuclear
collisions at BNL and CERN has been devoted to the experimental search for the
quark-gluon plasma predicted by QCD. The start of RHIC this year will increase
the highest available collision energy by a factor 10. This seems a good time
for a critical assessment: what have we learned so far and what can we hope to
learn in the coming years?

</DOC>
<DOC>
<DOCNO> 68019 </DOCNO>
Nonminimal global monopoles and bound orbits


  We perform a numerical analysis of the gravitational field of a global
monopole coupled nonminimally to gravity, and find that, for some given
nonminimal couplings (in constrast with the minimal coupling case), there is an
attractive region where bound orbits exist. We exhibit the behavior of the
frequency shifts that would be associated with `rotation curves' of stars in
circular orbits in the spacetimes of such global monopoles.

</DOC>
<DOC>
<DOCNO> 170632 </DOCNO>
Quantum Finite State Transducers


  We introduce quantum finite state transducers (qfst), and study the class of
relations which they compute. It turns out that they share many features with
probabilistic finite state transducers, especially regarding undecidability of
emptiness (at least for low probability of success). However, like their
`little brothers', the quantum finite automata, the power of qfst is
incomparable to that of their probabilistic counterpart. This we show by
discussing a number of characteristic examples.

</DOC>
<DOC>
<DOCNO> 11568 </DOCNO>
Double resonant processes in $\chi^{(2)}$ nonlinear periodic media


  In a one-dimensional periodic nonlinear $\chi^{(2)}$ medium, by choosing a
proper material and geometrical parameters of the structure, it is possible to
obtain two matching conditions for simultaneous generation of second and third
harmonics. This leads to new diversity of the processes of the resonant
three-wave interactions, which are discussed within the framework of slowly
varying envelope approach. In particular, we concentrate on the fractional
conversion of the frequency $\omega \to (2/3) \omega$. This phenomenon occurs
by means of intermediate energy transfer to the first harmonic at the frequency
$\omega/3$ and can be controlled by this mode. By analogy the same medium
allows "nondirect" second harmonic generation, controlled by the cubic
harmonic. Propagation of localized pulses in the form two coupled bright
solitons on first and third harmonics and a dark soliton on the second harmonic
is possible.

</DOC>
<DOC>
<DOCNO> 68810 </DOCNO>
Cosmological dynamics on the brane


  In Randall-Sundrum-type brane-world cosmologies, the dynamical equations on
the three-brane differ from the general relativity equations by terms that
carry the effects of imbedding and of the free gravitational field in the
five-dimensional bulk. We derive the covariant nonlinear dynamical equations
for the gravitational and matter fields on the brane, and then linearize to
find the perturbation equations on the brane. The local energy-momentum
corrections are significant only at very high energies. The imprint on the
brane of the nonlocal gravitational field in the bulk is more subtle, and we
provide a careful decomposition of this effect into nonlocal energy density,
flux and anisotropic stress. The nonlocal energy density determines the tidal
acceleration in the off-brane direction, and can oppose singularity formation
via the generalized Raychaudhuri equation. Unlike the nonlocal energy density
and flux, the nonlocal anisotropic stress is not determined by an evolution
equation on the brane. In particular, isotropy of the cosmic microwave
background may no longer guarantee a Friedmann geometry. Adiabatic density
perturbations are coupled to perturbations in the nonlocal bulk field, and in
general the system is not closed on the brane. But on super-Hubble scales,
density perturbations can be evaluated by brane observers. Tensor perturbations
on the brane are suppressed by local bulk effects during inflation, while the
nonlocal effects can serve as a source or a sink. Vorticity on the brane decays
as in general relativity, but nonlocal bulk effects can source the
gravito-magnetic field, so that vector perturbations can be generated in the
absence of vorticity.

</DOC>
<DOC>
<DOCNO> 11174 </DOCNO>
Statistical Physics of Vehicular Traffic and Some Related Systems


  In the so-called "microscopic" models of vehicular traffic, attention is paid
explicitly to each individual vehicle each of which is represented by a
"particle"; the nature of the "interactions" among these particles is
determined by the way the vehicles influence each others' movement. Therefore,
vehicular traffic, modeled as a system of interacting "particles" driven far
from equilibrium, offers the possibility to study various fundamental aspects
of truly nonequilibrium systems which are of current interest in statistical
physics. Analytical as well as numerical techniques of statistical physics are
being used to study these models to understand rich variety of physical
phenomena exhibited by vehicular traffic. Some of these phenomena, observed in
vehicular traffic under different circumstances, include transitions from one
dynamical phase to another, criticality and self-organized criticality,
metastability and hysteresis, phase-segregation, etc. In this critical review,
written from the perspective of statistical physics, we explain the guiding
principles behind all the main theoretical approaches. But we present detailed
discussions on the results obtained mainly from the so-called
"particle-hopping" models, particularly emphasizing those which have been
formulated in recent years using the language of cellular automata.

</DOC>
<DOC>
<DOCNO> 71987 </DOCNO>
Charged Higgs boson pair production via gluon-gluon collisions in MSSM


  The CP-violating effects to the subprocess $gg\to H^+H^-$ is studied in the
mSUGRA scenario at the CERN LHC, by taking into account the experimental bounds
of electron and neutron EDM's. The CP violation effects in this process are
related to the complex phases of $\mu$ and $A_{f}$ in the mSUGRA scenario. In
our calculation we consider small CP phases of $\mu$ and $A_{f}$ and neglect
the effects of neutral Higgs bosons mixing. In this case the CP effects to the
process mainly come from the complex couplings of Higgs-squark-squark. We find
a strong dependence of charged Higgs boson pair production rate on the complex
couplings in the MSSM parameter space.

</DOC>
<DOC>
<DOCNO> 174546 </DOCNO>
Study of Two-Step Mechanisms in Pion Absorption on 6Li, 12C via Deuteron


  The (pi+,pd), and (pi+,dd) reactions were investigated with pions of 100 and
165 MeV kinetic energy on 6Li and 12C targets. In comparison with previously
published (pi+,pp) data on the same targets and at the same beam energies,
kinematic regions were identified in which the neutron pickup process n+p->d
dominated the observed deuteron yield. The importance of this mechanism
increases with energy, contributing half of the observed cross section at 165
MeV. The contribution of direct quasi-triton absorption is significant only at
100 MeV.

</DOC>
<DOC>
<DOCNO> 178493 </DOCNO>
Odd-even staggering of binding energies as a consequence of pairing and


  Odd-even staggering of binding energies is studied in finite fermion systems
with pairing correlations. We discuss contributions of the pairing and
mean-field to the staggering, and we construct the binding-energy filters which
measure the magnitude of pairing correlations and the effective single-particle
spacings in a given system The analysis is based on studying several
exactly-solvable many-body Hamiltonians as well as on the analytical formulas
that can be applied in the weak and strong pairing limits.

</DOC>
<DOC>
<DOCNO> 8211 </DOCNO>
Analysis of occupational and displacive disorder using the atomic pair


  Many disordered crystalline materials show chemical short range order and
relaxation of neighboring atoms. Local structural information can be obtained
by analyzing the atomic pair distribution function (PDF). The viability of
reverse Monte Carlo (RMC) simulations to extract quantitative information about
chemical ordering as well as displacements is investigated. The method has been
applied to simulated PDFs of disordered structures showing chemical disorder
alone as well as in combination with displacements.

</DOC>
<DOC>
<DOCNO> 169724 </DOCNO>
Spiked and PT-symmetrized decadic potentials supporting elementary


  We show that the potential wells with a central spike
    V(x) = x^{10} + a x^8 + b x^6+ c x^4 + d x^2 + f/x^2 possess arbitrary
finite multiplets of elementary exact bound states. The strong asymptotic
growth of V(x) implies an ambiguity in the PT-symmetric quantization via
complex boundary conditions but the three eligible recipes coincide at our
exceptional solutions.

</DOC>
<DOC>
<DOCNO> 121149 </DOCNO>
The compact core-jet region of the superluminal quasar 3C216


  Space very long baseline interferometry (VLBI) observations of the quasar
3C216 with the VLBI Space Observatory Programme (VSOP) reveal that the parsec
scale structure of the source can be well described by compact jet models
developed for interpreting the core region of radio-loud active galactic nuclei
(AGN). The measured brightness temperature of T_(b) = 7.9*10^{11} K is
comparable to the inverse Compton limit, from which we determine a lower limit
of delta ~ 3.17 for the Doppler-boosting factor. The apparent transvers
velocity of the superluminal component is beta_(app) = (3.0+-0.2) h^{-1}
asuming a constant velocity, but deceleration of the jet material cannot be
excluded from our data. A combination of the above values indicates that the
viewing angle of the core-jet to the line-of-sight is less than 18.4 degrees,
and the jet Lorentz-factor exceeds 3.16. The observed small size of the source
is probably caused by both interaction with the interstellar medium, and a
projection effect.

</DOC>
<DOC>
<DOCNO> 85595 </DOCNO>
Gravitating macroscopic media in general relativity


  The problem of construction of a continuous (macroscopic) matter model for a
given point-like (microscopic) matter distribution in general relativity is
formulated. The existing approaches are briefly reviewed and a physical analogy
with the similar problem in classical macroscopic electrodynamics is pointed
out. The procedure by Szekeres in the linearized general relativity on
Minkowski background to construct a tensor of gravitational quadruple
polarization by applying Kaufman's method of molecular moments for derivation
of the polarization tensor in macroscopic electrodynamics and to derive an
averaged field operator by utilizing an analogy between the linearized Bianchi
identities and Maxwell equations, is analyzed. It is shown that the procedure
has some inconsistencies, in particular, (1) it has only provided the terms
linear in perturbations for the averaged field operator which do not contribute
into the dynamics of the averaged field, and (2) the analogy between
electromagnetism and gravitation does break upon averaging. A macroscopic
gravity approach in the perturbation theory up to the second order on a
particular background space-time taken to be a smooth weak gravitational field
is applied to write down a system of macroscopic field equations: Isaacson's
equations with a source incorporating the quadruple gravitational polarization
tensor, Isaacson's energy-momentum tensor of gravitational waves and
energy-momentum tensor of gravitational molecules and corresponding equations
of motion. A suitable set of material relations which relate all the tensors is
proposed.

</DOC>
<DOC>
<DOCNO> 150572 </DOCNO>
Comments on D branes and the renormalization group


  We review the de Boer-Verlinde-Verlinde formalism for the renormalization
group in the context of Dp brane vacua. We comment on various aspects of the
dictionary between bulk and boundary and relate the discussion to the
Randall-Sundrum scenario. We find that the gravitational coupling for the
Randall-Sundrum gravity on the Dp brane worldvolume is proportional to the
c-function of the Yang-Mills theory. We compute the beta function and find the
expected uneventful flow prescribed by the classical dimension of the
Yang-Mills operator. Finally, we argue for a dynamical mechanism for
determining the cosmology on the brane.

</DOC>
<DOC>
<DOCNO> 121028 </DOCNO>
The warm circumstellar envelope and wind of the G9 IIb star HR 6902


  IUE observations of the eclipsing binary system HR 6902 obtained at various
epochs spread over four years indicate the presence of warm circumstellar
material enveloping the G9 IIb primary. The spectra show Si IV and C IV
absorption up to a distance of 3.3 giant radii (R_g}. Line ratio diagnostics
yields an electron temperature of ~ 78000 K which appears to be constant over
the observed height range.
  Applying a least square fit absorption line analysis we derive column
densities as a function of height. We find that the inner envelope (< 3 R_g) of
the bright giant is consistent with a hydrostatic density distribution. The
derived line broadening velocity of ~ 70 kms^{-1} is sufficient to provide
turbulent pressure support for the required scale height. However, an improved
agreement with observations over the whole height regime including the emission
line region is obtained with an outflow model. We demonstrate that the common
beta power-law as well as a P \propto rho wind yield appropriate fit models.
Adopting a continuous mass outflow we obtain a mass-loss rate of M_loss= (0.8 -
3.4)*10^{-11} M_{sun}yr^{-1} depending on the particular wind model.

</DOC>
<DOC>
<DOCNO> 123232 </DOCNO>
X-ray Clusters of Galaxies as Tracers of Structure in the Universe


  Clusters of galaxies outline the network of the distribution of visible
matter in the Universe, marking the highest-mass knots where filamentary
structures join together. If we observe the sky in X rays, clusters of galaxies
stand out as cosmic lighthouses by virtue of a thin gas trapped and heated
within their gravitational potential wells. This powerful emission is directly
linked to the total gravitating mass they contain, such that they can be
efficiently used as tracers of the cosmic mass distribution within a sizeable
fraction of the observable Universe. Recent observational campaigns have for
the first time used X-ray clusters to map cosmic structures on scales
approaching 3 billion light years. The emerging picture is remarkably
consistent with the expectation of a low-density Universe dominated by cold
dark matter.

</DOC>
<DOC>
<DOCNO> 84801 </DOCNO>
Gravitational Effects of Rotating Bodies


  We study two type effects of gravitational field on mechanical gyroscopes
(i.e. rotating extended bodies). The first depends on special relativity and
equivalence principle. The second is related to the coupling (i.e. a new force)
between the spins of mechanical gyroscopes, which would violate the equivalent
principle. In order to give a theoretical prediction to the second we suggest a
spin-spin coupling model for two mechanical gyroscopes. An upper limit on the
coupling strength is then determined by using the observed perihelion
precession of the planet's orbits in solar system. We also give predictions
violating the equivalence principle for free-fall gyroscopes .

</DOC>
<DOC>
<DOCNO> 100780 </DOCNO>
Symmetries and reversing symmetries of toral automorphisms


  Toral automorphisms, represented by unimodular integer matrices, are
investigated with respect to their symmetries and reversing symmetries. We
characterize the symmetry groups of GL(n,Z) matrices with simple spectrum
through their connection with unit groups in orders of algebraic number fields.
For the question of reversibility, we derive necessary conditions in terms of
the characteristic polynomial and the polynomial invariants. We also briefly
discuss extensions to (reversing) symmetries within affine transformations, to
PGL(n,Z) matrices, and to the more general setting of integer matrices beyond
the unimodular ones.

</DOC>
<DOC>
<DOCNO> 9366 </DOCNO>
Mass enhancement in narrow band systems


  A perturbative study of the Holstein Molecular Crystal Model which accounts
for lattice structure and dimensionality effects is presented. Antiadiabatic
conditions peculiar of narrow band materials and an intermediate to strong
electron-phonon coupling are assumed. The polaron effective mass depends
crucially in all dimensions on the intermolecular coupling strengths which also
affect the size of the lattice deformation associated with the small polaron
formation.

</DOC>
<DOC>
<DOCNO> 119588 </DOCNO>
The Chandra X-ray Observatory Resolves the X-ray Morphology and Spectra


  The core-dominated radio-loud quasar PKS 0637-752 (z = 0.654) was the first
celestial object observed with the Chandra X-ray Observatory, offering the
early surprise of the detection of a remarkable X-ray jet. Several observations
with a variety of detector configurations contribute to a total exposure time
with the Chandra Advanced CCD Imaging Spectrometer (ACIS; Garmire et al. 2000,
in preparation) of about 100ks. A spatial analysis of all the available X-ray
data, making use of Chandra's spatial resolving power of about 0.4 arcsec,
reveals a jet that extends about 10 arcsec to the west of the nucleus. At least
four X-ray knots are resolved along the jet, which contains about 5% of the
overall X-ray luminosity of the source. Previous observations of PKS 0637-752
in the radio band (Tingay et al. 1998) had identified a kpc-scale radio jet
extending to the West of the quasar. The X-ray and radio jets are similar in
shape, intensity distribution, and angular structure out to about 9 arcsec,
after which the X-ray brightness decreases more rapidly and the radio jet turns
abruptly to the north. The X-ray luminosity of the total source is log Lx ~
45.8 erg/s (2 - 10keV), and appears not to have changed since it was observed
with ASCA in November 1996. We present the results of fitting a variety of
emission models to the observed spectral distribution, comment on the
non-existence of emission lines recently reported in the ASCA observations of
PKS 0637-752, and briefly discuss plausible X-ray emission mechanisms.

</DOC>
<DOC>
<DOCNO> 150650 </DOCNO>
The Vacua of 5d,N=2 Gauged Yang-Mills/Einstein/Tensor Supergravity:


  We give a detailed study of the critical points of the potentials of the
simplest non-trivial N=2 gauged Yang-Mills/Einstein supergravity theories with
tensor multiplets. The scalar field target space of these examples is
SO(1,1)XSO(2,1)/SO(2). The possible gauge groups are SO(2)XU(1)_R and
SO(1,1)XU(1)_R, where U(1)_R is a subgroup of the R-symmetry group SU(2)_R, and
SO(2) and SO(1,1) are subgroups of the isometry group of the scalar manifold.
The scalar potentials of these theories consist of a contribution from the
U(1)_R gauging and a contribution that is due to the presence of the tensor
fields. We find that the latter contribution can change the form of the
supersymmetric extrema from maxima to saddle points. In addition, it leads to
novel critical points not present in the corresponding gauged
Yang-Mills/Einstein supergravity theories without the tensor multiplets. For
the SO(2)XU(1)_R gauged theory these novel critical points correspond to
anti-de Sitter ground states. For the non-compact SO(1,1)XU(1)_R gauging, the
novel ground states are de Sitter. The analysis of the critical points of the
potential carries over in a straightforward manner to the generic family of N=2
gauged Yang-Mills/Einstein supergravity theories coupled to tensor multiplets
whose scalar manifolds are of the form SO(1,1)XSO(n-1,1)/SO(n-1).

</DOC>
<DOC>
<DOCNO> 13568 </DOCNO>
A model for single electron decays from a strongly isolated quantum dot


  Recent measurements of electron escape from a non-equilibrium charged quantum
dot are interpreted within a 2D separable model. The confining potential is
derived from 3D self-consistent Poisson-Thomas-Fermi calculations. It is found
that the sequence of decay lifetimes provides a sensitive test of the confining
potential and its dependence on electron occupation.

</DOC>
<DOC>
<DOCNO> 118820 </DOCNO>
The Radiative Stress Tensor


  We use the transfer equation in relativistic form to develop an expansion of
the one-photon distribution for a medium with constant photon mean free path,
$\epsilon$. The resulting radiative viscosity tensor may be expressed either as
a simple integral operator acting on the Thomas stress tensor or as the
solution of an inhomogenous, linear partial differential equation. The
expression obtained for the radiative viscosity tensor applies for media with
long, as well as short, photon mean free paths. We also develop results
applicable for relatively smooth flows by using the form of the Thomas stress
tensor with generalized transport coefficients derived by the application of a
suitable operator to the bare Thomas coefficients.

</DOC>
<DOC>
<DOCNO> 10285 </DOCNO>
Modelling fluctuations of financial time series: from cascade process to


  In this paper, we provide a simple, ``generic'' interpretation of
multifractal scaling laws and multiplicative cascade process paradigms in terms
of volatility correlations. We show that in this context 1/f power spectra, as
observed recently by Bonanno et al., naturally emerge. We then propose a simple
solvable ``stochastic volatility'' model for return fluctuations. This model is
able to reproduce most of recent empirical findings concerning financial time
series: no correlation between price variations, long-range volatility
correlations and multifractal statistics. Moreover, its extension to a
multivariate context, in order to model portfolio behavior, is very natural.
Comparisons to real data and other models proposed elsewhere are provided.

</DOC>
<DOC>
<DOCNO> 116638 </DOCNO>
Quantum mechanics can be led by metrics in Minkowski's time-space world


  A body of theory is completely different between relativity theory and
quantum mechanics. Most targeting physical phenomena are different between them
as well. Despite that both theories describe our time-space world, no one has
succeeded in arriving at one of these theories by using the other one,
deductively. Fusion of these two theories produced quantum field theory.
However this theory impresses us as a theory that was made by merging the two
theories by force. So this theory cannot indicate the reason why both
relativity theory and quantum mechanics exist in this world at the same time.
Here I show you that quantum mechanics can be led by the equation of
Minkowski's metrics, which stands up in the relativistic world of space and
time. This is the first report proving mathematically that quantum mechanics
can be born reductively in our relativistic world.

</DOC>
<DOC>
<DOCNO> 122276 </DOCNO>
NICMOS Imaging of the Host Galaxies of z ~ 2 - 3 Radio-Quiet Quasars


  We have made a deep NICMOS imaging study of a sample of 5 z ~ 2 - 3
radio-quiet quasars with low absolute nuclear luminosities, and we have
detected apparent host galaxies in all of these. Most of the hosts have
luminosities approximately equal to present-day L*, with a range from 0.2 L* to
about 4 L*. These host galaxies have magnitudes and sizes consistent with those
of the Lyman break galaxies at similar redshifts and at similar rest
wavelengths, but are about two magnitudes fainter than high-z powerful radio
galaxies. The hosts of our high-z sample are comparable to or less luminous
than the hosts of the low-z RQQs with similar nuclear absolute magnitudes.
However, the high z galaxies are more compact than the hosts of the low z
quasars, and probably have only 10 - 20% of the stellar mass of their low-z
counterparts. Application of the M(bulge)/M(BH) relation found for present-day
spheroids to the stellar masses implied for the high z host galaxies would
indicate that they contain black holes with masses around 10^8 Msolar.
Comparison to their nuclear magnitudes implies accretion rates that are near or
at the Eddington limit. Although these high z hosts already contain
supermassive black holes, the galaxies will need to grow significantly to
evolve into present-day L* galaxies. These results are basically consistent
with theoretical predictions for the hierarchical buildup of the galaxy host
and its relation to the central supermassive black hole.

</DOC>
<DOC>
<DOCNO> 9339 </DOCNO>
Relaxing Near the Critical Point


  Critical slowing down of the relaxation of the order parameter is relevant
both in early the universe and in ultrarelativistic heavy ion collisions. We
study the relaxation rate of the order parameter in an O(N) scalar theory near
the critical point to model the non-equilibrium dynamics of critical
fluctuations near the chiral phase transition.A lowest order perturbative
calculation (two loops in the coupling lambda) reveals the breakdown of
perturbation theory for long-wavelength fluctuations in the critical region and
the emergence of a hierarchy of scales with hard q>T, semisoft T >> q >> lambda
T and soft lambda T>>q loop momenta which are widely separated for weak
coupling. The non-perturbative resummation in the large N limit reveals the
renormalization of the interaction and the crossover to an effective 3D-theory
for soft momenta.The effective 3D coupling goes to the Wilson-Fisher 3D fixed
point in the soft limit.The relaxation rate of the order parameter for wave
vectors lambda T >>k>> k_{us} or near the critical temperature lambda
T>>m_T>>k_{us} with the ultra soft scale k_{us} = [(lambda T)/(4pi)]
exp[-(4pi/lambda)] is dominated by classical semisoft loop momentum leading to
Gamma(k,T) = lambda T/(2 pi N). For wavectors k<< k_{us} the damping rate is
dominated by hard loop momenta and given by Gamma(k,T)=4 pi T/[3N ln(T/k)].
Analogously, for homogeneous fluctuations in the ultracritical region
m_T<<k_{us} the damping rate is given by Gamma_0(m_T,T)=4 pi T/[3N ln(T/m_T)].
Thus critical slowing down emerges for ultrasoft fluctuations where the rate is
lambda-independent. The strong coupling regime and the shortcomings of the
quasiparticle interpretation are discussed.

</DOC>
<DOC>
<DOCNO> 117138 </DOCNO>
Generalized Radial Equations in a Quantum N-Body Problem


  We demonstrate how to separate the rotational degrees of freedom in a quantum
N-body problem completely from the internal ones. It is shown that any common
eigenfunction of the total orbital angular momentum ($\ell$) and the parity in
the system can be expanded with respect to $(2\ell+1)$ base-functions, where
the coefficients are the functions of the internal variables. We establish
explicitly the equations for those functions, called the generalized radial
equations, which are $(2\ell+1)$ coupled partial differential equations
containing only $(3N-6)$ internal variables.

</DOC>
<DOC>
<DOCNO> 70323 </DOCNO>
The effects of meson mixing on dilepton spectra


  The effect of scalar and vector meson mixing on the dilepton radiation from
hot and dense hadronic matter is estimated in different isospin channels. In
particular, we study the effect of $\sigma$-$\omega$ and $\rho-a_0$ mixing and
calculate the corresponding rates. Effects are found to be significant compared
to standard $\pi$-$\pi$ and $K$-${\bar K}$ annihilations. While the mixing in
the isoscalar channel mostly gives a contribution in the invariant mass range
between the two-pion threshold and the $\omega$ peak, the isovector channel
mixing induces an additional peak just below that of the $\phi$.
Experimentally, the dilepton signals from $\rho$-$a_0$ mixing seem to be more
tractable than those from $\sigma$-$\omega$ mixing.

</DOC>
<DOC>
<DOCNO> 83217 </DOCNO>
Reasoning with Individuals for the Description Logic SHIQ


  While there has been a great deal of work on the development of reasoning
algorithms for expressive description logics, in most cases only Tbox reasoning
is considered. In this paper we present an algorithm for combined Tbox and Abox
reasoning in the SHIQ description logic. This algorithm is of particular
interest as it can be used to decide the problem of (database) conjunctive
query containment w.r.t. a schema. Moreover, the realisation of an efficient
implementation should be relatively straightforward as it can be based on an
existing highly optimised implementation of the Tbox algorithm in the FaCT
system.

</DOC>
<DOC>
<DOCNO> 84957 </DOCNO>
General relativistic dynamics of compact binaries at the third


  The general relativistic corrections in the equations of motion and
associated energy of a binary system of point-like masses are derived at the
third post-Newtonian (3PN) order. The derivation is based on a post-Newtonian
expansion of the metric in harmonic coordinates at the 3PN approximation. The
metric is parametrized by appropriate non-linear potentials, which are
evaluated in the case of two point-particles using a Lorentzian version of an
Hadamard regularization which has been defined in previous works.
Distributional forms and distributional derivatives constructed from this
regularization are employed systematically. The equations of motion of the
particles are geodesic-like with respect to the regularized metric. Crucial
contributions to the acceleration are associated with the non-distributivity of
the Hadamard regularization and the violation of the Leibniz rule by the
distributional derivative. The final equations of motion at the 3PN order are
invariant under global Lorentz transformations, and admit a conserved energy
(neglecting the radiation reaction force at the 2.5PN order). However, they are
not fully determined, as they depend on one arbitrary constant, which reflects
probably a physical incompleteness of the point-mass regularization. The
results of this paper should be useful when comparing theory to the
observations of gravitational waves from binary systems in future detectors
VIRGO and LIGO.

</DOC>
<DOC>
<DOCNO> 152087 </DOCNO>
Functional Callan-Symanzik equation


  We describe a functional method to obtain the exact evolution equation of the
effective action with a parameter of the bare theory. When this parameter
happens to be the bare mass of the scalar field, we find a functional
generalization of the Callan-Symanzik equations. Another possibility is when
this parameter is the Planck constant and controls the amplitude of the
fluctuations. We show the similarity of these equations with the Wilsonian
renormalization group flows and also recover the usual one loop effective
action.

</DOC>
<DOC>
<DOCNO> 102453 </DOCNO>
On Hypersurface Quotient Singularity of Dimension 4


  We consider geometrical problems on Gorenstein hypersurface orbifolds of
dimension $n \geq 4$ through the theory of Hilbert scheme of group orbits. For
a linear special group $G$ acting on $\CZ^n$, we study the $G$-Hilbert scheme,
${\rm Hilb}^G(\CZ^n)$, and crepant resolutions of $\CZ^n/G$ for $G$=the
$A$-type abelian group $ A_r(n)$. For $n=4$, we obtain the explicit structure
of ${\rm Hilb}^{A_r(4)}(\CZ^4)$. The crepant resolutions of $\CZ^4/G$ are
constructed through their relation with ${\rm Hilb}^{A_r(4)}(\CZ^4)$, and the
connection between these crepant resolutions are found by the "flop" procedure
of 4-folds. We also make some primitive discussion on ${\rm Hilb}^G(\CZ^n)$ for
the $G$= alternating group ${\goth A}_{n+1}$ of degree $n+1$ with the standard
representation on $\CZ^n$; the detailed structure of ${\rm Hilb}^{{\goth
A}_4}(\CZ^3)$ is explicitly constructed.

</DOC>
<DOC>
<DOCNO> 119481 </DOCNO>
Semiclassical planetology : some results


  The aim of this lecture is to review the basic physical ideas and some
planetological results of the semiclassical theory of dense matter proposed by
P.Savic and R.Kasanin

</DOC>
<DOC>
<DOCNO> 150763 </DOCNO>
Testing the AdS/CFT correspondence beyond large N


  According to the AdS/CFT correspondence, the maximally supersymmetric SU(N)
Yang-Mills theory in 4 dimensions is dual to the type IIB string theory
compactified on AdS_5 x S^5. Most of the tests performed so far are confined to
the leading order at large N or equivalently string tree-level. To probe the
correspondence beyond this leading order and obtain 1/N^2 corrections is
difficult since string one-loop computations on an AdS_5 x S^5 background
generally are beyond feasibility. However, we will show that the chiral SU(4)_R
anomaly of the super YM theory provides an ideal testing ground to go beyond
leading order in N. We review and develop further our previous results that the
1/N^2 corrections to the chiral anomaly on the super YM side can be exactly
accounted for by the supergravity/string effective action induced at one loop.

</DOC>
<DOC>
<DOCNO> 71874 </DOCNO>
Calorons in Weyl Gauge


  We demonstrate by explicit construction that while the untwisted
Harrington-Shepard caloron $A_\mu$ is manifestly periodic in Euclidean time,
with period $\beta=\frac{1}{T}$, when transformed to the Weyl ($A_0=0$) gauge,
the caloron gauge field $A_i$ is periodic only up to a large gauge
transformation, with winding number equal to the caloron's topological charge.
This helps clarify the tunneling interpretation of these solutions, and their
relation to Chern-Simons numbers and winding numbers.

</DOC>
<DOC>
<DOCNO> 100379 </DOCNO>
On the Smooth Points of T-stable Varieties in G/B and the Peterson Map


  Let G be a semi-simple algebraic group over ${\mathbb C}$, B a Borel subgroup
of G and T a maximal torus in B. A beautiful unpublished result of Dale
Peterson says that if G is simply laced, then every rationally smooth point of
a Schubert variety X in G/B is nonsingular in X. The purpose of this paper is
to generalize this result to arbitrary T-stable subvarieties of G/B, the only
restriction being that G contains no $G_2$ factors. In particular, we show that
a Schubert variety X in such a G/B is nonsingular if and only if all the
reduced tangent cones of X are linear.

</DOC>
<DOC>
<DOCNO> 70414 </DOCNO>
Extra dimensions at the one loop level: Z -> b,b(bar) and B-B(bar)


  We study, at the one loop level, the dominant new physics contributions from
extra dimensions to Z -> b,b(bar), as well as B-B(bar) and K-K(bar) mixing. We
use a model with one extra dimension containing fermions which live in four
dimensions, and gauge bosons and one scalar doublet propagating in five
dimensions. We find that the effect of the infinite tower of Kaluza-Klein modes
in Z-> b,b(bar) is finite and gives a negative correction to
R_b=Gamma_b/Gamma_h, which is used to set a lower bound of 1 TeV on the
compactification scale M_c. On the other hand, we show that the box diagrams
contributing to B-B(bar) and K-K(bar) mixing are divergent and, after proper
regularization, we find that they increase the value of the function S(x_t)
which governs this mixing. The obtained value is perfectly compatible with
available data.

</DOC>
<DOC>
<DOCNO> 84450 </DOCNO>
Gravitational Waves in Open de Sitter Space


  We compute the spectrum of primordial gravitational wave perturbations in
open de Sitter spacetime. The background spacetime is taken to be the
continuation of an O(5) symmetric instanton saddle point of the Euclidean no
boundary path integral. The two-point tensor fluctuations are computed directly
from the Euclidean path integral. The Euclidean correlator is then analytically
continued into the Lorentzian region where it describes the quantum mechanical
vacuum fluctuations of the graviton field. Unlike the results of earlier work,
the correlator is shown to be unique and well behaved in the infrared. We show
that the infrared divergence found in previous calculations is due to the
contribution of a discrete gauge mode inadvertently included in the spectrum.

</DOC>
<DOC>
<DOCNO> 102800 </DOCNO>
The cup product of the Hilbert scheme for K3 surfaces


  To any graded Frobenius algebra A we associate a sequence of graded Frobenius
algebras A^[n] in such a way that for any smooth projective surface X with
trivial canonical divisor there is a canonical isomorphism of rings between
(H*X)^[n] and the cohomology H*(X^[n]) of the n-th Hilbert scheme of X.

</DOC>
<DOC>
<DOCNO> 71401 </DOCNO>
Correlation of Ultra High Energy Cosmic Rays with Compact Radio Loud


  Angular correlations of ultra-high energy cosmic rays with cosmologically
distant sources may provide clues to these mysterious events. We compare cosmic
ray tracks with energies above $ 10^{20}eV$ to a compilation of radio-loud
compact QSO positions. The statistical method emphasizes invariant quantities
and a test of {\it statistical independence} of track and source distributions.
Statistical independence is ruled out by several independent statistics at
confidence levels of less that $10^{-3}$ ($99.9% $.), indicating that track
directions and QSO source positions are correlated at a highly significant
level.

</DOC>
<DOC>
<DOCNO> 178591 </DOCNO>
Pairing gaps from nuclear mean-field models


  We discuss the pairing gap, a measure for nuclear pairing correlations, in
chains of spherical, semi-magic nuclei in the framework of self-consistent
nuclear mean-field models. The equations for the conventional BCS model and the
approximate projection-before-variation Lipkin-Nogami method are formulated in
terms of local density functionals for the effective interaction. We calculate
the Lipkin-Nogami corrections of both the mean-field energy and the pairing
energy. Various definitions of the pairing gap are discussed as three-point,
four-point and five-point mass-difference formulae, averaged matrix elements of
the pairing potential, and single-quasiparticle energies. Experimental values
for the pairing gap are compared with calculations employing both a delta
pairing force and a density-dependent delta interaction in the BCS and
Lipkin-Nogami model. Odd-mass nuclei are calculated in the spherical blocking
approximation which neglects part of the the core polarization in the odd
nucleus. We find that the five-point mass difference formula gives a very
robust description of the odd-even staggering, other approximations for the gap
may differ from that up to 30% for certain nuclei.

</DOC>
<DOC>
<DOCNO> 117232 </DOCNO>
A Measurement of the Three-Dimensional Clustering of C IV


  We examine the three-dimensional clustering of C IV absorption-line systems,
using an extensive catalog of QSO heavy-element absorbers drawn from the
literature. We measure clustering by a volume-weighted integral of the
correlation function called the reduced second-moment measure, and include
information from both along and across QSO lines of sight, thus enabling a full
determination of the three-dimensional clustering of absorbers, as well as a
comparison of line- and cross-line-of-sight clustering properties. Here we
present the three-dimensional reduced second-moment estimator for a
three-dimensional point process probed by one-dimensional lines of sight, and
apply our algorithm to a sample of 345 C IV absorbers with median redshift of
2.2, drawn from the spectra of 276 QSOs. We confirm the existence of
significant clustering on comoving scales up to 100 Mpc, and find that the
additional cross-line-of-sight information strengthens the evidence for
clustering on scales from 100 Mpc to 150 Mpc. There is no evidence of absorber
clustering along or across lines of sight for scales from 150 Mpc to 300 Mpc.
We show that with a 300-times larger catalog, such as that to be compiled by
the Sloan Digital Sky Survey (100,000 QSOs), use of the full three-dimensional
estimator and cross-line-of-sight information will substantially increase
clustering sensitivity. We find that standard errors are reduced by an
additional factor of 2 to 20 on scales of 30 to 200 Mpc, effectively increasing
the sample size by an extra factor of 4 to 400 at large distances.

</DOC>
<DOC>
<DOCNO> 117882 </DOCNO>
Perturbative Analysis of Adaptive Smoothing Methods in Quantifying


  Smoothing operation to make continuous density field from observed point-like
distribution of galaxies is crucially important for topological or
morphological analysis of the large-scale structure, such as, the genus
statistics or the area statistics (equivalently the level crossing statistics).
It has been pointed out that the adaptive smoothing filters are more efficient
tools to resolve cosmic structures than the traditional spatially fixed
filters. We study weakly nonlinear effects caused by two representative
adaptive methods often used in smoothed hydrodynamical particle (SPH)
simulations. Using framework of second-order perturbation theory, we calculate
the generalized skewness parameters for the adaptive methods in the case of
initially power-law fluctuations.
 Then we apply the multidimensional Edgeworth expansion method and investigate
weakly nonlinear evolution of the genus statistics and the area statistics.
Isodensity contour surfaces are often parameterized by the volume fraction of
the regions above a given density threshold. We also discuss this
parameterization method in perturbative manner.

</DOC>
<DOC>
<DOCNO> 83071 </DOCNO>
PushPush is NP-hard in 2D


  We prove that a particular pushing-blocks puzzle is intractable in 2D,
improving an earlier result that established intractability in 3D [OS99]. The
puzzle, inspired by the game *PushPush*, consists of unit square blocks on an
integer lattice. An agent may push blocks (but never pull them) in attempting
to move between given start and goal positions. In the PushPush version, the
agent can only push one block at a time, and moreover, each block, when pushed,
slides the maximal extent of its free range. We prove this version is NP-hard
in 2D by reduction from SAT.

</DOC>
<DOC>
<DOCNO> 99345 </DOCNO>
Examples of nonuniqueness for an inverse problems of geophysics


  The inverse problem of finding the velocity profile from the surface
measurements of acoustic field is considered. The dimensionalities of the data
and of the unknown velocity profile are equal, both are equal 3. Analytical
explicit examples are given showing vast non-uniqueness of the solution to this
inverse problem.

</DOC>
<DOC>
<DOCNO> 71462 </DOCNO>
Strong Decays of Scalar Glueball in a Scale-Invariant Chiral Quark Model


  An effective meson Lagrangian including a scalar glueball is constructed on
the base of $U(3)\times U(3)$ chiral symmetry. The glueball is introduced into
the meson Lagrangian by using the principle of scale invariance of an effective
Lagrangian and the dilaton model. The singlet-octet mixing of scalar meson
states is described by means of 't Hooft interaction. The contribution of the
scalar and pseudoscalar anomalies into the breaking of scale invariance is
taken into account. The mixing of quarkonia with the glueball is described. The
mass spectrum of scalar mesons together with the glueball and also their strong
decay widths are calculated. From comparing the obtained results with
experimental data, it follows that $f_0(1500)$ is rather a glueball, whereas
$f_0(1710)$ is a quarkonium. This accords with the results obtained in our
previous works where radially-excited scalar meson states were described. It is
shown that $\rho$-mesons play an important role in the description of glueball
decays.

</DOC>
<DOC>
<DOCNO> 84770 </DOCNO>
On long-time evolution in general relativity and geometrization of


  We describe some relations between the long-time asymptotic behavior of the
vacuum Einstein evolution equations and the geometrization of 3-manifolds.
These relations are expressed in terms of evolution of CMC hypersurfaces in the
vacuum space-time.Some results are also obtained on the singularity avoidance
of CMC foliations. In addition, the paper describes a number of open problems
relating these two areas.

</DOC>
<DOC>
<DOCNO> 85365 </DOCNO>
Dissipative Fluid in Brans Dicke theory and late time acceleration


  We have investigated the possibility of having a late time accelerated
expansion phase for the universe. We have used a dissipative fluid in
Brans-Dicke(BD) theory for this purpose. The model does not involve any
potential for the BD scalar field. We have obtained the best fit values for the
different parameters in our model by comparing our model predictions with SNIa
data and the also with the data from the ultra-compact radio sources.

</DOC>
<DOC>
<DOCNO> 152554 </DOCNO>
Exact spinor-scalar bound states in a QFT with scalar interactions


  We study two-particle systems in a model quantum field theory, in which
scalar particles and spinor particles interact via a mediating scalar field.
The Lagrangian of the model is reformulated by using covariant Green's
functions to solve for the mediating field in terms of the particle fields.
This results in a Hamiltonian in which the mediating-field propagator appears
directly in the interaction term. It is shown that exact two-particle
eigenstates of the Hamiltonian can be determined. The resulting relativistic
fermion-boson equation is shown to have Dirac and Klein-Gordon one-particle
limits. Analytic solutions for the bound state energy spectrum are obtained for
the case of massless mediating fields.

</DOC>
<DOC>
<DOCNO> 80663 </DOCNO>
Canonical Discretization. I. Discrete faces of (an)harmonic oscillator


  A certain notion of canonical equivalence in quantum mechanics is proposed.
It is used to relate quantal systems with discrete ones. Discrete systems
canonically equivalent to the celebrated harmonic oscillator as well as the
quartic and the quasi-exactly-solvable anharmonic oscillators are found. They
can be viewed as a translation-covariant discretization of the (an)harmonic
oscillator preserving isospectrality. The notion of the $q-$deformation of the
canonical equivalence leading to a dilatation-covariant discretization
preserving polynomiality of eigenfunctions is also presented.

</DOC>
<DOC>
<DOCNO> 122557 </DOCNO>
Oxygen line formation in 3D hydrodynamical model atmospheres


  The formation of [O I], O I and OH lines in metal-poor stars has been studied
by means of 3D hydrodynamical model atmospheres. For O I detailed 3D non-LTE
calculations have been performed. While the influence of 3D model atmospheres
is minor for [O I] and O I lines, the very low temperatures encountered at low
metallicities have a drastic impact on the OH lines. As a result, the derived O
abundances are found to be systematically overestimated in 1D analyses, casting
doubts on the recent claims for a monotonic increase in [O/Fe] towards lower
metallicities.

</DOC>
<DOC>
<DOCNO> 84690 </DOCNO>
Quantum Geometrodynamics in the Bohm-de Broglie Interpretation


  In this thesis the Bohm-de Broglie interpretation of quantum mechanics is
applied to canonical quantum gravity. It is shown that, irrespective of any
regularization or choice of factor ordering of the Wheeler-DeWitt equation, the
unique relevant quantum effect which does not break spacetime is the change of
its signature from lorentzian to euclidean. The other quantum effects are
either trivial or break the four-geometry of spacetime. A Bohm-de Broglie
picture of quantum geometrodynamics is constructed, which allows the
investigation of these latter structures. For instance, it is shown that any
real solution of the Wheeler-De Witt equation yields a generate four-geometry
compatible with the strong gravity limit of General Relativity and the Carroll
group. We prove that quantum geometrodynamics in the Bohm-de Broglie
interpretation is consistent for any quantum potential. As a previous step to
introduce our metodology, we study the quantum theory of fields in Minkowski
spacetime in the Bohm-de Broglie interpretation and exhibit a concrete example
where Lorentz invariance of individual events is broken.

</DOC>
<DOC>
<DOCNO> 178482 </DOCNO>
Equilibration within a semiclassical off-shell transport approach


  Equilibration times for nuclear matter configurations -- modelling
intermediate and high energy nucleus-nucleus collisions -- are evaluated within
the semiclassical off-shell transport approach developed recently. The
transport equations are solved for a finite box in coordinate space employing
periodic boundary conditions. The off-shell transport model is shown to give
proper off-shell equilibrium distributions in the limit $t \to \infty$ for the
nucleon and $\Delta$-resonance spectral functions. We find that equilibration
times within the off-shell approach are only slightly enhanced as compared to
the on-shell limit for the momentum configurations considered.

</DOC>
<DOC>
<DOCNO> 100146 </DOCNO>
Bures Measures over the Spaces of Two and Three-Dimensional Density


  Due to considerable recent interest in the use of density matrices for a wide
variety of purposes, including quantum computation, we present a general method
for their parameterizations in terms of Euler angles. We assert that this is of
more fundamental importance than (as several people have remarked to us) ``just
another parameterization of the density matrix.'' There are several uses to
which this methodology can be put. One that has received particular attention
is in the construction of certain distinguished (Bures) measures on the $(n^2
-1)$-dimensional convex sets of $n \times n$ density matrices.

</DOC>
<DOC>
<DOCNO> 10758 </DOCNO>
Numerical Test of Disk Trial Wave function for Half-Filled Landau Level


  The analyticity of the lowest Landau level wave functions and the relation
between filling factor and the total angular momentum severely limits the
possible forms of trial wave functions of a disk of electrons subject to a
strong perpendicular magnetic field. For N, the number of electrons, up to 12
we have tested these disk trial wave functions for the half filled Landau level
using Monte Carlo and exact diagonalization methods. The agreement between the
results for the occupation numbers and ground state energies obtained from
these two methods is excellent. We have also compared the profile of the
occupation number near the edge with that obtained from a field-theoretical
method. The results give qualitatively identical edge profiles. Experimental
consequences are briefly discussed.

</DOC>
<DOC>
<DOCNO> 116534 </DOCNO>
A Brief Note on Discrete Space Effects


  We discuss briefly discrete space effects and show that this leads to space
reflection asymmetry and also a minor modification of Einstein's energy-mass
formula.

</DOC>
<DOC>
<DOCNO> 118869 </DOCNO>
The Parameter Space Occupied by Galaxies: The Optical Window


  We discuss the optical parameter space (luminosity and surface brightness)
over which galaxies are known to exist and report on the results from three
recent datasets: the Two-degree Field Galaxy Redshift Survey, the Hubble Deep
Field north, and the Local Group. These data are combined to provide a unique
and comprehensive insight into the luminosity distribution of galaxies over the
range -24 < M(B) < -8 mags, and the surface brightness distribution over the
range 18 < SB(Effective) < 28 mags/sq arcsec. The main conclusions are: (1)
luminous low surface brightness galaxies are rare; (2) there exists a universal
luminosity-surface brightness relation; (3) the most numerous galaxies are low
luminosity low surface brightness dwarfs.

</DOC>
<DOC>
<DOCNO> 102281 </DOCNO>
Enumeration of ad-nilpotent $\frak b$-ideals for simple Lie algebras


  We provide explicit formulas for the number of ad-nilpotent ideals of a Borel
subalgebra of a complex simple Lie algebra having fixed class of nilpotence.

</DOC>
<DOC>
<DOCNO> 85252 </DOCNO>
Non spherical sources of strong gravitational fields out of hydrostatic


  We describe the departure from equilibrium of matter distributions
representing sources for a class of Weyl metric. It is shown that, for
extremely high gravitational fields, slight deviations from spherical symmetry
may enhance the stability of the system weakening thereby its tendency to a
catastrophic collapse. For critical values of surface gravitational potential,
in contrast with the exactly spherically symmetric case, the speed of entering
the collapse regime decreases substantially, at least for specific cases.

</DOC>
<DOC>
<DOCNO> 70277 </DOCNO>
Three Loop Free Energy Using Screened Perturbation Theory


  The conventional weak-coupling expansion for the pressure of a hot plasma
shows no sign of convergence unless the the coupling constant $g$ is tiny. In
this talk, I discuss screened perturbation theory (SPT) which is a
reorganization of the perturbative expansion by adding and subtracting a local
mass term in the Lagrangian. We consider several different mass prescriptions,
and compute the pressure to three-loop order. The SPT-improved approximations
appear to converge for rather large values of the coupling constant.

</DOC>
<DOC>
<DOCNO> 152553 </DOCNO>
Looking for event horizons using UV/IR relations


  A primary goal in holographic theories of gravity is to study the causal
structure of spacetime from the field theory point of view. This is a
particularly difficult problem when the spacetime has a non-trivial causal
structure, such as a black hole. We attempt to study causality through the
UV/IR relation between field theory and spacetime quantities, which encodes
information about bulk position. We study the UV/IR relations for charged black
hole spacetimes in the AdS/CFT correspondence. We find that the UV/IR relations
have a number of interesting features, but find little information about the
presence of a horizon in the bulk. The scale of Wilson loops is simply related
to radial position, whether there is a horizon or not. For time-dependent
probes, the part of the history near the horizon only effects the late-time
behaviour of field theory observables. Static supergravity probes have a finite
scale size related to radial position in generic black holes, but there is an
interesting logarithmic divergence as the temperature approaches zero.

</DOC>
<DOC>
<DOCNO> 11612 </DOCNO>
Bulk experimental evidence of half-metallic ferromagnetism in doped


  We report precise measurements and quantitative data analysis on the
low-temperature resistivity of several ferromagnetic manganite films. We
clearly show that there exists a T^{4.5} term in low-temperature resistivity,
and that this term is in quantitative agreement with the quantum theory of
two-magnon scattering for half metallic ferromagnets. Our present results
provide the first bulk experimental evidence of half-metallic ferromagnetism in
doped manganites.

</DOC>
<DOC>
<DOCNO> 67734 </DOCNO>
The atmospheric neutrino anomaly without maximal mixing?


  We consider a pattern of neutrino masses in which there is an approximate
mass degeneracy between the two mass eigenstates most coupled to the $\nu_\mu$
and $\nu_\tau$ flavour eigenstates. Earth-matter effects can lift this
degeneracy and induce an effectively maximal mixing between these two
generations. This occurs if $\nu_e$'s contain comparable admixtures of the
degenerate eigenstates, even rather small ones. This provides an explanation of
the atmospheric neutrino anomaly in which the {\it ab initio} introduction of a
large mixing angle is not required. To test this possibility we perform a novel
and detailed analysis of the 52 kiloton-year SuperKamiokande data, and we find
that in a large region of parameter space the corresponding confidence levels
are excellent. The most recent results from the Chooz reactor experiment,
however, severely curtail this region, so that the conventional scenario with
nearly maximal mixing angles --which we also analyse in detail-- is supported
by the data.

</DOC>
<DOC>
<DOCNO> 169797 </DOCNO>
Welcher Weg Experiments and the Orthodox Bohr's Complementarity


  In its most orthodox form, Bohr's Complementarity Principle states that a
quanton (a quantum system consisting of a Boson or Fermion) can either behave
as a particle or as wave, but never simultaneosuly as both. A less orthodox
interpretation of this Principle is the ``duality condition'' embodied in a
mathematical inequality due to Englert [B-G Englert, Phys. Rev. Lett., Vol. 77,
2154 (1996)] which allows wave and particle attributes to co-exist, but
postulates that a stronger manifestation of the particle nature leads to a
weaker manifestation of the wave nature and vice versa. In this Letter, we show
that some recent {\it welcher weg} ("which path") experiments in
interferometers and similar set-ups, that claim to have validated, or
invalidated, the Complementarity Principle, actually shed no light on the
orthodox interpretation. They may have instead validated the weaker duality
condition, but even that is not completely obvious. We propose simple
modifications to these experiments which we believe can test the orthodox
Complementarity Principle and also shed light on the nature of wavefunction
collapse and quantum erasure.

</DOC>
<DOC>
<DOCNO> 118015 </DOCNO>
Damped Ly-alpha Systems in Semi-Analytic Models: Sensitivity to


  Previously we have shown that it is possible to account for the kinematic
properties of damped Lyman alpha systems (DLAS) in the context of semi-analytic
models. In these models, hierarchical structure formation is approximated by
constructing a merger tree for each dark matter halo. A natural consequence is
that every virialized halo may contain not only a central galaxy, but also a
number of satellite galaxies as determined by its merging history. Thus the
kinematics of the DLAS arise from the combined effects of the internal rotation
of gas disks and the motions between gas disks within a common halo. Here we
investigate the sensitivity of this model to some of the assumptions made
previously, including the modeling of satellite dynamics, the scale height of
the gas, and the cosmology.

</DOC>
<DOC>
<DOCNO> 119615 </DOCNO>
Measurement of [OIII] Emission in Lyman Break Galaxies


  Measurements of [OIII] emission in Lyman Break galaxies (LBGs) at z>3 are
presented. Four galaxies were observed with narrow-band filters using the
Near-IR Camera on the Keck I 10-m telescope. A fifth galaxy was observed
spectroscopically during the commissioning of NIRSPEC, the new infrared
spectrometer on Keck II. The emission-line spectrum is used to place limits on
the metallicity. Comparing these new measurements with others available from
the literature, we find that strong oxygen emission in LBGs may suggest
sub-solar metallicity for these objects. The [OIII]5007 line is also used to
estimate the star formation rate (SFR) of the LBGs. The inferred SFRs are
higher than those estimated from the UV continuum, and may be evidence for dust
extinction.

</DOC>
<DOC>
<DOCNO> 169705 </DOCNO>
Phase measurements at the theoretical limit


  It is well known that the result of any phase measurement on an optical mode
made using linear optics has an introduced uncertainty in addition to the
intrinsic quantum phase uncertainty of the state of the mode.
 The best previously published technique [H.M. Wiseman and R.B. Killip, Phys.
Rev. A {\bf 57}, 2169 (1998)] is an adaptive technique that introduces a phase
variance that scales as $\bar{n}^{-1.5}$, where $\bar{n}$ is the mean photon
number of the state. This is far above the minimum intrinsic quantum phase
variance of the state, which scales as $\bar{n}^{-2}$. It has been shown that a
lower limit to the phase variance that is introduced scales as
$\ln(\bar{n})/\bar{n}^2$. Here we introduce an adaptive technique that attains
this theoretical lower limit.

</DOC>
<DOC>
<DOCNO> 11426 </DOCNO>
Topographic Mapping of the Quantum Hall Liquid using a Few-Electron


  A scanning probe technique was used to obtain a high-resolution map of the
random electrostatic potential inside the quantum Hall liquid. A sharp metal
tip, scanned above a semiconductor surface, sensed charges in an embedded
two-dimensional electron gas. Under quantum Hall effect conditions, applying a
positive voltage to the tip locally enhanced the 2D electron density and
created a ``bubble'' of electrons in an otherwise unoccupied Landau level. As
the tip scanned along the sample surface, the bubble followed underneath. The
tip sensed the motions of single electrons entering or leaving the bubble in
response to changes in the local 2D electrostatic potential.

</DOC>
<DOC>
<DOCNO> 121123 </DOCNO>
On the occurrence of dwarf nova outbursts in post novae


  We show that irradiation of the accretion disc by the white dwarf limits the
occurrence of dwarf nova outbursts in post nova accretion discs. After the nova
explosion, the white dwarf has to cool for up to ~100 yr - depending on the
orbital period (i.e., disc size) and the temperature of the white dwarf after
the nova-eruption - before the disc can begin producing dwarf nova outbursts.
During this time the inner disc is maintained in a hot, ionised state. Using
these calculations, we interpret the long-term photometric variability of the
post nova V446 Her (Nova Her 1960) which shows today regular dwarf nova
outbursts. As the white dwarf in V446 Her continues to cool over the next
\~10-20 yr, we predict an increase in the amplitude of outbursts and a decrease
of the outburst frequency, because the decreasing irradiation of the accretion
disc should allow an increasing annular extent of the accretion disc to
participate in limit cycle oscillations.

</DOC>
<DOC>
<DOCNO> 100865 </DOCNO>
From slightly coloured noises to unitless product systems


  Stationary Gaussian generalized random processes having slowly decreasing
spectral densities give rise to product systems in the sense of William Arveson
(basically, continuous tensor product systems of Hilbert spaces). A continuum
of nonisomorphic unitless product systems is produced, answering a question of
Arveson.

</DOC>
<DOC>
<DOCNO> 170041 </DOCNO>
Universal Quantum Computation with the Exchange Interaction


  Experimental implementations of quantum computer architectures are now being
investigated in many different physical settings. The full set of requirements
that must be met to make quantum computing a reality in the laboratory is
daunting, involving capabilities well beyond the present state of the art.
Theory can aid experiment by exposing new alternative routes for achieving
quantum computation by simpler means. In this report we indicate one route to
simplification that would apply to many recent solid-state approaches, using
quantum dots, and using donor-atom nuclear spins or electron spins. In all
these approaches, the basic two-qubit quantum gate is generated by a tunable
Heisenberg interaction (the Hamiltonian is $H_{ij}=J(t){\vec S}_i\cdot{\vec
S}_j$ between spins i and j); we show here that, at the expense of increasing
the number of devices and the number of computational steps by constant
factors, the Heisenberg interaction alone suffices to exactly implement any
quantum computer circuit. An explicit assessment of the tradeoffs involved is
given.

</DOC>
<DOC>
<DOCNO> 69059 </DOCNO>
Cold Dark Matter and b --> s gamma in the Horava-Witten Theory


  The minimal supersymmetric standard model with complete, partial or no Yukawa
unification and radiative electroweak breaking with boundary conditions from
the Horava-Witten theory is considered. The parameters are restricted by
constraining the lightest sparticle relic abundance by cold dark matter
considerations and requiring the b-quark mass after supersymmetric corrections
and the branching ratio of b --> s gamma to be compatible with data. Complete
Yukawa unification can be excluded. Also, t-b Yukawa unification is strongly
disfavored since it requires almost degenerate lightest and next-to-lightest
sparticle masses. However, the b-tau or no Yukawa unification cases avoid this
degeneracy. The latter with mu<0 is the most natural case. The lightest
sparticle mass, in this case, can be as low as about 77 GeV.

</DOC>
<DOC>
<DOCNO> 100085 </DOCNO>
Exponential and moment inequalities for U-statistics


  A Bernstein-type exponential inequality for (generalized) canonical
U-statistics of order 2 is obtained and the Rosenthal and Hoffmann-J{\o}rgensen
inequalities for sums of independent random variables are extended to
(generalized) U-statistics of any order whose kernels are either nonnegative or
canonical

</DOC>
<DOC>
<DOCNO> 120661 </DOCNO>
Accretion column disruption in GX 1+4


  Daily observations of the binary X-ray pulsar GX 1+4 were made with the Rossi
X-ray Timing Explorer (RXTE) satellite between 1997 May 16-20 as part of a
four-month monitoring program. On May 17 the sharp dips normally observed in
the lightcurve were all but absent, resulting in a pulse fraction f_p approx.
0.5 instead of the more typical value of approx. 0.8 measured before and after.
Also observed was a dramatic hardening of the 2-40 keV phase-averaged spectrum.
The power-law photon index was 1.16 +/- 0.02, whereas values of 1.6-2.0 are
more typical. In terms of a Comptonization continuum component, the optical
depth for scattering was tau approx 19, with 4-6 the usual range for RXTE
spectra (Galloway 2000). Pulse-phase spectrosopy indicates that tau is
decreased relative to the phase-averaged value around the primary minimum,
where an increase is normally observed. The reduced depth of the dip is
interpreted as disruption of the accretion column, and the accompanying
spectral variation suggests a substantially different accretion regime than is
usual for this source.

</DOC>
<DOC>
<DOCNO> 102054 </DOCNO>
On 2D Euler Equations: Part II. Lax Pairs and Homoclinic Structures


  In Part I of our study on 2D Euler equation, we established the spectral
theorem for a linearized 2D Euler equation. We also computed the point spectrum
through continued fractions, and identified the eigenvalues with nonzero real
parts.
  In this Part II of our study, first we discuss the Lax pairs for both 2D and
3D Euler equations. The existence of Lax pairs suggests that the hyperbolic
foliations of 2D and 3D Euler equations may be degenerate, i.e., there exist
homoclinic structures. Then we investigate the question on the degeneracy v.s.
nondegeneracy of the hyperbolic foliations for Galerkin truncations of 2D Euler
equation. In particular, for a Galerkin truncation, we have computed the
explicit representation of the hyperbolic foliation which is of the degenerate
case, i.e., figure-eight case. We also study the robustness of this degeneracy
for a so-called dashed-line model through higher order Melnikov functions. The
first order and second order Melnikov functions are all identically zero, which
indicates that the degeneracy is relatively robust. The study in this paper
serves a clue in searching for homoclinic structures for 2D Euler equation. The
recent breakthrough result of mine on the existence of a Lax pair for 2D Euler
equation, strongly supports the possible existence of homoclinic structures for
2D Euler equation.

</DOC>
<DOC>
<DOCNO> 84888 </DOCNO>
Relation of the oscillator and Coulomb systems on spheres and


  It is shown, that oscillators on the sphere and the pseudosphere are related,
by the so-called Bohlin transformation, with the Coulomb systems on the
pseudosphere. The even states of an oscillator yield the conventional Coulomb
system on the pseudosphere, while the odd states yield the Coulomb system on
the pseudosphere in the presence of magnetic flux tube generating spin 1/2. A
similar relation is established for the oscillator on the (pseudo)sphere
specified by the presence of constant uniform magnetic field $B_0$ and the
Coulomb-like system on pseudosphere specified by the presence of the magnetic
field $\frac{B}{2r_0}(|\frac{x_3}{{\bf x}}|-\epsilon)$. The correspondence
between the oscillator and the Coulomb systems the higher dimensions is also
discussed.

</DOC>
<DOC>
<DOCNO> 10444 </DOCNO>
Instabilities of waves in nonlinear disordered media


  We develop a self-consistent theory of temporal fluctuations of a speckle
pattern resulting from the multiple scattering of a coherent wave in a weakly
nonlinear disordered medium. The speckle pattern is shown to become unstable if
the nonlinearity exceeds a threshold value. The instability is due to a
feedback provided by the multiple scattering and manifests itself in
spontaneous fluctuations of the scattered intensity. The development of
instability is independent of the sign of nonlinearity.

</DOC>
<DOC>
<DOCNO> 84466 </DOCNO>
Freedman-Townsend vertex from Hamiltonian BRST cohomology


  Consistent interactions among a set of two-form gauge fields in four
dimensions are derived along a Hamiltonian cohomological procedure. It is shown
that the deformation of the BRST charge and BRST-invariant Hamiltonian for the
free model leads to the Freedman-Townsend interaction vertex. The resulting
interaction deforms both the gauge transformations and reducibility relations,
but not the algebra of gauge transformations.

</DOC>
<DOC>
<DOCNO> 11096 </DOCNO>
Carrier-induced ferromagnetism in p-Zn1-xMnxTe


  We present a systematic study of the ferromagnetic transition induced by the
holes in nitrogen doped Zn1-xMnxTe epitaxial layers, with particular emphasis
on the values of the Curie-Weiss temperature as a function of the carrier and
spin concentrations. The data are obtained from thorough analyses of the
results of magnetization, magnetoresistance and spin-dependent Hall effect
measurements. The experimental findings compare favorably, without adjustable
parameters, with the prediction of the Rudermann-Kittel-Kasuya-Yosida (RKKY)
model or its continuous-medium limit, that is, the Zener model, provided that
the presence of the competing antiferromagnetic spin-spin superexchange
interaction is taken into account, and the complex structure of the valence
band is properly incorporated into the calculation of the spin susceptibility
of the hole liquid. In general terms, the findings demonstrate how the
interplay between the ferromagnetic RKKY interaction, carrier localization, and
intrinsic antiferromagnetic superexchange affects the ordering temperature and
the saturation value of magnetization in magnetically and electrostatically
disordered systems.

</DOC>
<DOC>
<DOCNO> 13121 </DOCNO>
Giant and time-dependent magnetocaloric effect in high-spin molecular


  We have measured and calculated the magnetocaloric effect in macroscopic
samples of oriented high-spin molecular clusters like Mn12 and Fe8 as a
function of the temperature and both the intensity and the sweeping rate of the
applied magnetic field. We have observed a high magnetic entropy variation
around the blocking temperature of the magnetic moment of molecules and
calculated the shift of the entropy variation and cooling temperature, with the
sweeping rate of the magnetic field.

</DOC>
<DOC>
<DOCNO> 8665 </DOCNO>
Measurement of a Quantum System Coupled to Independent Heat-Bath and


  We present an exact derivation of a process in which a microscopic measured
system interacts with heat-bath and pointer modes of a measuring device, via a
coupling involving a general Hermitian operator $\Lambda$ of the system. In the
limit of strong interaction with these modes, over a small time interval, we
derive the exact effective many-body density matrix of the measured system plus
pointer. We then discuss the interpretation of the dynamics considered as the
first stage in the process of quantum measurement, eventually involving the
wave-function collapse due to interactions with "the rest of the universe." We
establish that the effective density matrix represents the required framework
for the measured system and the pointer part of the measuring device to evolve
into a statistical mixture described by direct-product states such that the
system is in each eigenstate of $\Lambda$ with the correct quantum-mechanical
probability, whereas the expectation values of pointer-space operators retain
amplified information of the system's eigenstate.

</DOC>
<DOC>
<DOCNO> 9101 </DOCNO>
Quantum chiral phases in frustrated easy-plane spin chains


  The phase diagram of antiferromagnetic spin-S chain with XY-type anisotropy
and frustrating next-nearest-neighbor interaction is studied in the limit of
large integer S with the help of a field-theoretical approach. It is shown that
the existence of gapless and gapped chiral phases found in recent numerical
studies [M.Kaburagi et al., J. Phys. Soc. Jpn. vol.68, 3185 (1999), T.Hikihara
et al., J. Phys. Soc. Jpn. vol.69, 259 (2000)] is not specific for S=1, but is
rather a generic large-S feature. Estimates for the corresponding transition
boundaries are obtained, and a sketch of the typical phase diagram is
presented. It is also shown that frustration stabilizes the Haldane phase
against the variation of the anisotropy.

</DOC>
<DOC>
<DOCNO> 8456 </DOCNO>
Statistical Physics of Structural Glasses


  This paper gives an introduction and brief overview of some of our recent
work on the equilibrium thermodynamics of glasses. We have focused onto first
principle computations in simple fragile glasses, starting from the two body
interatomic potential. A replica formulation translates this problem into that
of a gas of interacting molecules, each molecule being built of $m$ atoms, and
having a gyration radius (related to the cage size) which vanishes at zero
temperature. We use a small cage expansion, valid at low temperatures, which
allows to compute the cage size, the specific heat (which follows the Dulong
and Petit law), and the configurational entropy. The no-replica interpretation
of the computations is also briefly described. The results, particularly those
concerning the Kauzmann tempaerature and the configurational entropy, are
compared to recent numerical simulations.

</DOC>
<DOC>
<DOCNO> 13206 </DOCNO>
Aging and SOC in driven dissipative systems


  We study the noisy dynamics of a close relative of the sand pile model.
Depending on the type of noise and the time scale of observation, we find
stationary fluctuations (similar to SOC) or an aging dynamics with punctuated
equilibria, a decreasing rate of events and reset properties qualitatively
similar to those of glassy systems and evolution models.

</DOC>
<DOC>
<DOCNO> 120837 </DOCNO>
Sub-parsec-scale Accleration of the Radio Jet in the Powerful Radio


  In order to investigate the genesis of powerful radio jet, we have mapped the
central 10 pc region of the nearby radio galaxy NGC 6251 with a 0.2 pc
resolution using Very Long Baseline Interferometer (VLBI) at two radio
frequencies, 5 GHz and 15 GHz, we have found the sub-parsec-scale counterjet
for the first time in this radio galaxy. This discovery allows us to
investigate the jet acceleration based on the relativistic beaming model.

</DOC>
<DOC>
<DOCNO> 122536 </DOCNO>
Doppler Tomography


  I review the method of Doppler tomography which translates binary-star line
profiles taken at a series of orbital phases into a distribution of emission
over the binary. I begin with a discussion of the basic principles behind
Doppler tomography, including a comparison of the relative merits of maximum
entropy regularisation versus filtered back-projection for implementing the
inversion. Following this I discuss the issue of noise in Doppler images and
possible methods for coping with it. Then I move on to look at the results of
Doppler Tomography applied to cataclysmic variable stars. Outstanding successes
to date are the discovery of two-arm spiral shocks in cataclysmic variable
accretion discs and the probing of the stream/magnetospheric interaction in
magnetic cataclysmic variable stars. Doppler tomography has also told us much
about the stream/disc interaction in non-magnetic systems and the irradiation
of the secondary star in all systems. The latter indirectly reveals such
effects as shadowing by the accretion disc or stream. I discuss all of these
and finish with some musings on possible future directions for the method. At
the end I include a tabulation of Doppler maps published in refereed journals.

</DOC>
<DOC>
<DOCNO> 118746 </DOCNO>
Modeling Nonaxisymmetric Bow Shocks: Solution Method and Exact Analytic


  A new solution method is presented for steady-state, momentum-conserving,
non-axisymmetric bow shocks and colliding winds in the thin-shell limit. This
is a generalization of previous formulations to include a density gradient in
the pre-shock ambient medium, as well as anisotropy in the pre-shock wind. For
cases where the wind is unaccelerated, the formalism yields exact, analytic
solutions.
  Solutions are presented for two bow shock cases: (1) that due to a star
moving supersonically with respect to an ambient medium with a density gradient
perpendicular to the stellar velocity, and (2) that due to a star with a
misaligned, axisymmetric wind moving in a uniform medium. It is also shown
under quite general circumstances that the total rate of energy thermalization
in the bow shock is independent of the details of the wind asymmetry, including
the orientation of the non-axisymmetric driving wind, provided the wind is
non-accelerating and point-symmetric. A typical feature of the solutions is
that the region near the standoff point is tilted, so that the star does not
lie along the bisector of a parabolic fit to the standoff region. The principal
use of this work is to infer the origin of bow shock asymmetries, whether due
to the wind or ambient medium, or both.

</DOC>
<DOC>
<DOCNO> 72229 </DOCNO>
Supersymmetric Radion in the Randall-Sundrum Scenario


  We derive the effective action for the radion supermultiplet in the
supersymmetric Randall-Sundrum model with two opposite tension branes.

</DOC>
<DOC>
<DOCNO> 85474 </DOCNO>
Scalar-tensor $\sigma$-cosmologies


  We show that the scalar-tensor $\sigma$-model action is conformally
equivalent to general relativity with a minimally coupled wavemap with a
particular target metric. Inflation on the source manifold is then shown to
occur in a natural way due both to the arbitrary curvature couplings and the
wavemap self-interactions.

</DOC>
<DOC>
<DOCNO> 14176 </DOCNO>
Average Time Spent by Levy Flights and Walks on an Interval with


  We consider a Levy flyer of order alpha that starts from a point x0 on an
interval [O,L] with absorbing boundaries. We find a closed-form expression for
the average number of flights the flyer takes and the total length of the
flights it travels before it is absorbed. These two quantities are equivalent
to the mean first passage times for Levy flights and Levy walks, respectively.
Using fractional differential equations with a Riesz kernel, we find exact
analytical expressions for both quantities in the continuous limit. We show
that numerical solutions for the discrete Levy processes converge to the
continuous approximations in all cases except the case of alpha approaching 2
and the cases of x0 near absorbing boundaries. For alpha larger than 2 when the
second moment of the flight length distribution exists, our result is replaced
by known results of classical diffusion. We show that if x0 is placed in the
vicinity of absorbing boundaries, the average total length has a minimum at
alpha=1, corresponding to the Cauchy distribution. We discuss the relevance of
this result to the problem of foraging, which has received recent attention in
the statistical physics literature.

</DOC>
<DOC>
<DOCNO> 12209 </DOCNO>
Structural and Energetic Heterogeneity in Protein Folding


  A general theoretical framework is developed using free energy functional
methods to understand the effects of heterogeneity in the folding of a
well-designed protein. Native energetic heterogeneity arising from
non-uniformity in native stability, as well as entropic heterogeneity intrinsic
to the topology of the native structure are both investigated as to their
impact on the folding free energy landscape and resulting folding mechanism.
Given a minimally frustrated protein, both structural and energetic
heterogeneity lower the thermodynamic barrier to folding, and designing in
sufficient heterogeneity can eliminate the barrier at the folding transition
temperature. Sequences with different distributions of stability throughout the
protein and correspondingly different folding mechanisms may still be good
folders to the same structure. This theoretical framework allows for a
systematic study of the coupled effects of energetics and topology in protein
folding, and provides interpretations and predictions for future experiments
which may investigate these effects.

</DOC>
<DOC>
<DOCNO> 116310 </DOCNO>
Is it Possible to Transfer an Information with the Velocities Exceeding


  On the base of the theory of time and space with the fractional dimensions a
possibility for information transferring with arbitrary velocities is
demonstrated

</DOC>
<DOC>
<DOCNO> 100413 </DOCNO>
An information-spectrum approach to joint source-channel coding


  Given a general source $\sV=\{V^n\}\noi$ with {\em countably infinite} source
alphabet and a general channel $\sW=\{W^n\}\noi$ with arbitrary {\em abstract}
channel input and output alphabets, we study the joint source-channel coding
problem from the information-spectrum point of view. First, we generalize
Feinstein's lemma (direct part) and Verd\'u-Han's lemma (converse part) so as
to be applicable to the general joint source-channel coding problem. Based on
these lemmas, we establish a sufficient condition as well as a necessary
condition for the source $\sV$ to be reliably transmissible over the channel
$\sW$ with asymptotically vanishing probability of error. It is shown that our
sufficient condition coincides with the sufficient condition derived by Vembu,
Verd\'u and Steinberg, whereas our necessary condition is much stronger than
the necessary condition derived by them. Actually, our necessary condition
coincide with our sufficient condition if we disregard some asymptotically
vanishing terms appearing in those conditions. Also, it is shown that {\em
Separation Theorem} in the generalized sense always holds. In addition, we
demonstrate a sufficient condition as well as a necessary condition for the
$\vep$-transmissibility ($0\le \vep <1$). Finally, the separation theorem of
the traditional standard form is shown to hold for the class of sources and
channels that satisfy the (semi-) strong converse property.

</DOC>
<DOC>
<DOCNO> 83242 </DOCNO>
A Decision-Theoretic Approach to Resource Allocation in Wireless


  The allocation of scarce spectral resources to support as many user
applications as possible while maintaining reasonable quality of service is a
fundamental problem in wireless communication. We argue that the problem is
best formulated in terms of decision theory. We propose a scheme that takes
decision-theoretic concerns (like preferences) into account and discuss the
difficulties and subtleties involved in applying standard techniques from the
theory of Markov Decision Processes (MDPs) in constructing an algorithm that is
decision-theoretically optimal. As an example of the proposed framework, we
construct such an algorithm under some simplifying assumptions. Additionally,
we present analysis and simulation results that show that our algorithm meets
its design goals. Finally, we investigate how far from optimal one well-known
heuristic is. The main contribution of our results is in providing insight and
guidance for the design of near-optimal admission-control policies.

</DOC>
<DOC>
<DOCNO> 14006 </DOCNO>
The Effect of Helicity on the Effective Diffusivity for Incompressible


  The advection of a passive scalar by a quenched (frozen) incompressible
velocity field is studied by extensive high precision numerical simulation and
various approximation schemes. We show that second order self consistent
perturbation theory, in the absence of helicity, perfectly predicts the
effective diffusivity of a tracer particle in such a field. In the presence of
helicity in the flow simulations reveal an unexpectedly strong enhancement of
the effective diffusivity which is highly nonperturbative and is most visible
when the bare molecular diffusivity of the particle is small. We develop and
analyse a series of approximation schemes which indicate that this enhancement
of the diffusivity is due to a novel second order effect whereby the helical
component of the field, which does not directly renormalize the effective
diffusivity, enhances the strength of the non helical part of the flow, which
in turn renormalizes the molecular diffusivity. We show that this
renormalization is most important at low bare molecular diffusivity, in
agreement with the numerical simulations.

</DOC>
<DOC>
<DOCNO> 68133 </DOCNO>
Cross Sections for the Dissociation of J/psi and psi' by pi and rho at


  Using the quark-interchange model of Barnes and Swanson, we evaluate the
dissociation cross sections for $J/\psi$ and $\psi'$ by $\pi$ and $\rho$ at low
collision energies. In collisions with $\pi$ mesons near threshold the $\pi +
J/\psi$ dissociation cross section is predicted to be small, but the $\pi
+\psi'$ cross section is found to be quite large, in qualitative agreement with
experimental data on $J/\psi$ and $\psi'$ production in high-energy heavy-ion
collisions. The $\rho + J/\psi$ and $\rho + \psi'$ dissociation cross sections
are both predicted to be large numerically and are divergent near threshold.
These $\rho + J/\psi$ and $\rho + \psi'$ cross sections show considerable
sensitivity to the mass of the $\rho$ meson if it is off energy shell.

</DOC>
<DOC>
<DOCNO> 10262 </DOCNO>
Nonperturbative infrared dynamics of three-dimensional QED with a


  A non-linear Schwinger-Dyson (SD) equation for the gauge boson propagator of
massless QED in one time and two spatial dimensions is studied. It is shown
that the nonperturbative solution leads to a nontrivial renormalization-group
infrared fixed point quantitatively close to the one found in the leading order
of the 1/N expansion, with N the number of fermion flavors. In the gauged
Nambu-Jona-Lasinio (GNJL) model an equation for the Yukawa vertex is solved in
an approximation given by the one-photon exchange and an analytic expression is
derived for the propagator of the scalar fermion-antifermion composites.
Subsequently, the mass and width of the scalar composites near the phase
transition line are calculated as functions of the four-fermion coupling g and
flavor number N. The possible relevance of these results for describing
particle-hole excitations, in particular antiferromagnetic correlations,
observed in the underdoped cuprates, is briefly discussed.

</DOC>
<DOC>
<DOCNO> 120720 </DOCNO>
Mid-infrared imaging of the massive young star AFGL 2591: Probing the


  Most, if not all, stars are now believed to produce energetic outflows during
their formation. Yet, almost 20 years after the discovery of bipolar outflows
from young stars, the origins of this violent phenomenon are not well
understood. One of the difficulties of probing the outflow process,
particularly in the case of massive embedded stars, is a deficit of high
spatial resolution observations. Here, we present sub-arcsecond-resolution
mid-infrared images of one massive young stellar object, AFGL 2591, and its
immediate surroundings. Our images, at 11.7, 12.5 and 18.0 microns, reveal a
knot of emission ~6'' SW of the star, which may be evidence for a recent
ejection event or an embedded companion star. This knot is roughly coincident
with a previously seen near-infrared reflection nebula and a radio source, and
lies within the known large-scale CO outflow. We also find a new faint NW
source which may be another embedded lower-luminosity star. The IRAS
mid-infrared spectrum of AFGL 2591 shows a large silicate absorption feature at
10 microns, implying that the primary source is surrounded by an optically
thick dusty envelope. We discuss the interrelationship of these phenomena and
suggest that mid-infrared imaging and spectroscopy provide powerful tools for
probing massive star birth.

</DOC>
<DOC>
<DOCNO> 122961 </DOCNO>
Global Constraints On Key Cosmological Parameters


  Data from Type Ia supernovae, along with X-ray cluster estimates of the
universal baryon fraction and Big Bang Nucleosynthesis (BBN) determinations of
the baryon-to-photon ratio, are used to provide estimates of several global
cosmological parameters at epochs near zero redshift. We show that our estimate
of the present baryon density is in remarkably good agreement with that
inferred from BBN at high redshift, provided the primordial abundance of
deuterium is relatively low and the Universe is flat. We also compare these
estimates to the baryon density at z = 1100 as inferred from the CMB angular
power spectrum.

</DOC>
<DOC>
<DOCNO> 178957 </DOCNO>
The Isospin Asymmetry in the Pseudo-spin Dynamical Symmetry


  Pseudo-spin symmetry in nuclei is investigated considering the Dirac equation
with a Lorentz structured Woods-Saxon potential. The isospin correlation of the
energy splittings of pseudo-spin partners with the nuclear potential parameters
is studied. We show that in an isotopic chain, the pseudo-spin symmetry is
better realized for neutrons than for protons. This behavior comes from balance
effects amongst the central nuclear potential parameters. In general, we found
an isospin asymmetry of the nuclear pseudo-spin interaction, opposed to the
nuclear spin-orbit interaction which is quasi isospin symmetric.

</DOC>
<DOC>
<DOCNO> 8035 </DOCNO>
Fourier Acceleration of Langevin Molecular Dynamics


  Fourier acceleration has been successfully applied to the simulation of
lattice field theories for more than a decade. In this paper, we extend the
method to the dynamics of discrete particles moving in continuum. Although our
method is based on a mapping of the particles' dynamics to a regular grid so
that discrete Fourier transforms may be taken, it should be emphasized that the
introduction of the grid is a purely algorithmic device and that no smoothing,
coarse-graining or mean-field approximations are made. The method thus can be
applied to the equations of motion of molecular dynamics (MD), or its Langevin
or Brownian variants. For example, in Langevin MD simulations our acceleration
technique permits a straightforward spectral decomposition of forces so that
the long-wavelength modes are integrated with a longer time step, thereby
reducing the time required to reach equilibrium or to decorrelate the system in
equilibrium. Speedup factors of up to 30 are observed relative to pure
(unaccelerated) Langevin MD. As with acceleration of critical lattice models,
even further gains relative to the unaccelerated method are expected for larger
systems. Preliminary results for Fourier-accelerated molecular dynamics are
presented in order to illustrate the basic concepts. Possible extensions of the
method and further lines of research are discussed.

</DOC>
<DOC>
<DOCNO> 12240 </DOCNO>
The quantum phase transition of itinerant helimagnets


  We investigate the quantum phase transition of itinerant electrons from a
paramagnet to a state which displays long-period helical structures due to a
Dzyaloshinskii instability of the ferromagnetic state. In particular, we study
how the self-generated effective long-range interaction recently identified in
itinerant quantum ferromagnets is cut-off by the helical ordering. We find that
for a sufficiently strong Dzyaloshinskii instability the helimagnetic quantum
phase transition is of second order with mean-field exponents. In contrast, for
a weak Dzyaloshinskii instability the transition is analogous to that in
itinerant quantum ferromagnets, i.e. it is of first order, as has been observed
in MnSi.

</DOC>
<DOC>
<DOCNO> 68742 </DOCNO>
Inelastic electroproduction of $\eta_c$ at ep colliders


  Using the nonrelativistic QCD factorization formalism, we calculate the
electroproduction cross sections of $\eta_c$ in ep collisions, including the
contribution from both the transverse photon and the longitudinal photon. For
this process the color-singlet contribution vanishes up to the next to leading
order perturbative QCD calculations. The dominant contribution comes from the
color-octet ${}^1S_0^{(8)}$ subprocess. The nonperturbative color-octet matrix
element of ${}^1S_0^{(8)}$ of $\eta_c$ is related to that of ${}^3S_1^{(8)}$ of
$J/\psi$ by heavy quark spin symmetry, and the latter can be determined from
the direct production of $J/\psi$ at large transverse momentum at the Fermilab
Tevatron. The measurement of this process at DESY HERA can be viewed as another
independent test for the color-octet production mechanism

</DOC>
<DOC>
<DOCNO> 117829 </DOCNO>
Infrared spectroscopy of cataclysmic variables: III. Dwarf novae below


  We present K-band spectra of the short-period dwarf novae YZ Cnc, LY Hya, BK
Lyn, T Leo, SW UMa and WZ Sge, the novalike variables DW UMa, V1315 Aql, RW
Tri, VY Scl, UU Aqr and GP Com, and a series of field dwarf stars with spectral
types ranging from K2-M6.
  The spectra of the dwarf novae are dominated by emission lines of HI and HeI.
The large velocity and equivalent widths of these lines, in conjunction with
the fact that the lines are double-peaked in the highest inclination systems,
indicate an accretion disc origin. In the case of YZ Cnc and T Leo, for which
we obtained time-resolved data covering a complete orbital cycle, the emission
lines show modulations in their equivalent widths which are most probably
associated with the bright spot (the region where the gas stream collides with
the accretion disc). There are no clear detections of the secondary star in any
of the dwarf novae below the period gap, yielding upper limits of 10-30% for
the contribution of the secondary star to the observed K-band flux. In
conjunction with the K-band magnitudes of the dwarf novae, we use the derived
secondary star contributions to calculate lower limits to the distances to
these systems.
  The spectra of the novalike variables are dominated by broad, single-peaked
emission lines of HI and HeI - even the eclipsing systems we observed do not
show the double-peaked profiles predicted by standard accretion disc theory.
With the exception of RW Tri, which exhibits NaI, CaI and 12CO absorption
features consistent with a M0V secondary contributing 65% of the observed
K-band flux, we find no evidence for the secondary star in any of the novalike
variables. The implications of this result are discussed.

</DOC>
<DOC>
<DOCNO> 80664 </DOCNO>
On Pure Lattice Chern-Simons Gauge Theories


  We revisit the lattice formulation of the Abelian Chern-Simons model defined
on an infinite Euclidean lattice. We point out that any gauge invariant, local
and parity odd Abelian quadratic form exhibits, in addition to the zero
eigenvalue associated with the gauge invariance and to the physical zero mode
at p=0 due to traslational invariance, a set of extra zero eigenvalues inside
the Brillouin zone. For the Abelian Chern-Simons theory, which is linear in the
derivative, this proliferation of zero modes is reminiscent of the
Nielsen-Ninomiya no-go theorem for fermions. A gauge invariant, local and
parity even term such as the Maxwell action leads to the elimination of the
extra zeros by opening a gap with a mechanism similar to that leading to Wilson
fermions on the lattice.

</DOC>
<DOC>
<DOCNO> 101281 </DOCNO>
Evidence for a conjecture of Pandharipande


  In his paper "Hodge integrals and degenerate contributions", Pandharipande
studied the relationship between the enumerative geometry of certain 3-folds
and the Gromov-Witten invariants. In some good cases, enumerative invariants
(which are manifestly integers) can be expressed as a rational combination of
Gromov-Witten invariants. Pandharipande speculated that the same combination of
invariants should yield integers even when they do not have any enumerative
significance on the 3-fold. In the case when the 3-fold is the product of a
complex surface and an elliptic curve, Pandharipande has computed this
combination of invariants on the 3-fold in terms of the Gromov-Witten
invariants of the surface. This computation yields surprising conjectural
predictions about the genus 0 and genus 1 Gromov-Witten invariants of complex
surfaces. The conjecture states that certain rational combinations of the genus
0 and genus 1 Gromov-Witten invariants are always integers. Since the
Gromov-Witten invariants for surfaces are often enumerative (as oppose to
3-folds), this conjecture can often also be interpreted as giving certain
congruence relations among the various enumerative invariants of a surface.
  In this note, we state Pandharipande's conjecture and we prove it for an
infinite series of classes in the case of the projective plane blown-up at 9
points. In this case, we find generating functions for the numbers appearing in
the conjecture in terms of quasi-modular forms. We then prove the integrality
of the numbers by proving a certain a congruence property of modular forms that
is reminiscent of Ramanujan's mod 5 congruences of the partition function.

</DOC>
<DOC>
<DOCNO> 120578 </DOCNO>
Testing the AGN models for the X-ray background


  We will briefly examine the following three issues related to the AGN
synthesis models for X-ray background: 1) the possibility that absorbed AGNs
evolve faster than unabsorbed ones; 2) the existence of the still debated
population of luminous absorbed AGNs, the so-called QSO2s; 3) the behavior of
the AGN density at a redshift above ~3.

</DOC>
<DOC>
<DOCNO> 10133 </DOCNO>
Entropic lattice Boltzmann methods


  We present a general methodology for constructing lattice Boltzmann models of
hydrodynamics with certain desired features of statistical physics and kinetic
theory. We show how a methodology of linear programming theory, known as
Fourier-Motzkin elimination, provides an important tool for visualizing the
state space of lattice Boltzmann algorithms that conserve a given set of
moments of the distribution function. We show how such models can be endowed
with a Lyapunov functional, analogous to Boltzmann's H, resulting in
unconditional numerical stability. Using the Chapman-Enskog analysis and
numerical simulation, we demonstrate that such entropically stabilized lattice
Boltzmann algorithms, while fully explicit and perfectly conservative, may
achieve remarkably low values for transport coefficients, such as viscosity.
Indeed, the lowest such attainable values are limited only by considerations of
accuracy, rather than stability. The method thus holds promise for
high-Reynolds number simulations of the Navier-Stokes equations.

</DOC>
<DOC>
<DOCNO> 69795 </DOCNO>
Gravitational Collapse: The Story so far


  An outstanding problem in gravitation theory and relativistic astrophysics
today is to understand the final outcome of an endless gravitational collapse.
Such a continual collapse would take place when stars more massive than few
times the mass of the sun collapse under their own gravity on exhausting their
nuclear fuel. According to the general theory of relativity, this results
either in a black hole, or a naked singularity- which can communicate with
faraway observers in the universe. While black holes are (almost) being
detected and are increasingly used to model high energy astrophysical
phenomena, naked singularities have turned into a topic of active discussion,
aimed at understanding their structure and implications. Recent developments
here are reviewed, indicating future directions.

</DOC>
<DOC>
<DOCNO> 169995 </DOCNO>
Optically Driven Qubits in Artificial Molecules


  We present novel models of quantum gates based on coupled quantum dots in
which a qubit is regarded as the superposition of ground states in each dot.
Coherent control on the qubit is performed by both a frequency and a
polarization of a monochromatic light pulse illuminated on the quantum dots. We
also show that a simple combination of two single qubit gates functions as a
controlled NOT gate resulting from an electron-electron interaction. To examine
the decoherence of quantum states, we discuss electronic relaxation contributed
mainly by LA phonon processes.

</DOC>
<DOC>
<DOCNO> 71952 </DOCNO>
Prediction of three heavy spin-0 particles in the SM


  The axial-vector couplings of the internediate bosons with fermions lead to
the prediction of three very heavy spin-0 states in the SM, whose masses are
about 10^{14}GeV. If these states on mass shell there are problems of negative
probability. A new perturbation theory of the SM is proposed.

</DOC>
<DOC>
<DOCNO> 102461 </DOCNO>
Random perturbations of non-uniformly expanding maps


  We give both sufficient conditions and necessary conditions for the
stochastic stability of non-uniformly expanding maps either with or without
critical sets. We also show that the number of probability measures describing
the statistical asymptotic behaviour of random orbits is bounded by the number
of SRB measures if the noise level is small enough.
 As an application of these results we prove the stochastic stability of
certain classes of non-uniformly expanding maps introduced in \cite{V} and
\cite{ABV}.

</DOC>
<DOC>
<DOCNO> 101690 </DOCNO>
Numerical Approximation of Real Functions and One Minkowski's Conjecture


  In this paper I consider the applications of several kinds of approximations
of real functions to the problem of verified computation (reliable computing)
of the range of implicitly defined real function $x_{n+1} = G(x_{1}, ...,
x_{n}),$ where dependency $F(x_{1}, ..., x_{n+1}) = 0$ is defined on some
compact domain by a sufficiently smooth real function $F(x_{1}, ..., x_{n+1})
>.$ Constructive version of Kolmogorov-Arnold and implicit function theorems,
results about floating-point approximation, floating-point approximations which
give lower-bound and upper-bound estimates of some real functions, and
approximate algebraic computation are used for the purpose. The rigorous theory
can be build on the base of analysis on manifolds over floating points domains.
In the text we demonstrate our approach on examples from investigation of
Minkowski's conjecture on critical determinant of the region $\mid x \mid^p +
\mid y \mid^p \leq 1, p > 1.$.

</DOC>
<DOC>
<DOCNO> 10589 </DOCNO>
Spontaneous symmetry breaking in the finite, lattice quantum sine-Gordon


  The spontaneous breaking of a global discrete translational symmetry in the
finite, lattice quantum sine-Gordon model is demonstrated by a density matrix
renormalization group. A phase diagram in the coupling constant - inverse
system size plane is obtained. Comparison of the phase diagram with a
Woomany-Wyld finite-size scaling leads to an identification of the
Berezinskii-Kosterlitz-Thouless transition in the quantum sine-Gordon model as
the spontaneous symmetry breaking.

</DOC>
<DOC>
<DOCNO> 11591 </DOCNO>
Convergence to the critical attractor of dissipative maps: Log-periodic


  For a family of logistic-like maps, we investigate the rate of convergence to
the critical attractor when an ensemble of initial conditions is uniformly
spread over the entire phase space. We found that the phase space volume
occupied by the ensemble $W(t)$ depicts a power-law decay with log-periodic
oscillations reflecting the multifractal character of the critical attractor.
We explore the parametric dependence of the power-law exponent and the
amplitude of the log-periodic oscillations with the attractor's fractal
dimension governed by the inflexion of the map near its extremal point.
Further, we investigate the temporal evolution of $W(t)$ for the circle map
whose critical attractor is dense. In this case, we found $W(t)$ to exhibit a
rich pattern with a slow logarithmic decay of the lower bounds. These results
are discussed in the context of non-extensive Tsallis entropies.

</DOC>
<DOC>
<DOCNO> 11387 </DOCNO>
Interplay of spin and orbital ordering in the layered colossal


  The crystallographic and magnetic phase diagram of the n=2 layered manganite
La2-2xSr1+2xMn2O7 in the region x=>0.5 has been studied using temperature
dependent neutron powder diffraction. The magnetic phase diagram reveals a
progression of ordered magnetic structures generally paralleling that of 3-D
perovskites with similar electronic doping: A (0.5<=x<=0.66) --> C
(0.75<=x<=0.90) --> G (0.90<=x<=1.0). However, the quasi-2-D structure
amplifies this progression to expose features of manganite physics uniquely
accessible in the layered systems: (a) a "frustrated" region between the A and
C regimes where no long-range magnetic order is observed; (b) magnetic
polytypism arising from weak inter-bilayer magnetic exchange in the Type-C
regime; and (c) a tetragonal to orthorhombic phase transition whose temperature
evolution directly measures ordering of d3y2-r2 orbitals in the a-b plane. This
orbital-ordering transition is precursory to Type-C magnetic ordering, where
ferromagnetic rods lie parallel to the b-axis. These observations support the
notion that eg orbital polarisation is the driving force behind magnetic spin
ordering. Finally, in the crossover region between Type-C and Type-G states, we
see some evidence for the development of local Type-C clusters embedded in a
Type-G framework, directly addressing proposals of similar short-range magnetic
ordering in highly-doped La1-xCaxMnO3 perovskites.

</DOC>
<DOC>
<DOCNO> 102250 </DOCNO>
Symmetry, singularities and integrability in complex dynamics II:


  The explicit integrability of second order ordinary differential equations
invariant under time-translation and rescaling is investigated. Quadratic
systems generated from the linearisable version of this class of equations are
analysed to determine therelationship between the Painlev\'e and singularity
properties of the different systems. The transformation contains a parameter
and for critical values, intimately related to the possession of the Painlev\'e
Property in the parent second order equation, one finds a difference from the
generic behaviour. This study is a prelude to a full discussion of the class of
transformations which preserve the Painlev\'e Property in the construction of
quadratic systems from scalar nonlinear odes invariant under time translation
and rescaling.

</DOC>
<DOC>
<DOCNO> 169939 </DOCNO>
Partitioning optical solitons for generating entangled light beams


  It is shown that bipartition of optical solitons can be used to generate
entangled light beams. The achievable amount of entanglement can be
substantially larger for N-bound solitons N=2,3 than for the fundamental
soliton (N=1). An analysis of the mode structure of the entangled beams shows
that just N modes are essentially entangled. In particular, partitioning of the
fundamental soliton effectively produces 2-mode squeezed light.

</DOC>
<DOC>
<DOCNO> 118030 </DOCNO>
Revealing the Photodissociation Region: Hubble Space Telescope/NICMOS


  We report results from a Hubble Space Telescope (HST) and Near-Infrared
Camera and Multiobject Spectrometer (NICMOS) program to study the distribution
of hot neutral (molecular hydrogen) and ionized circumstellar material in the
young planetary nebulae NGC 7027. HST/NICMOS provided very high spatial
resolution imaging in line and continuum emission, and the stability and large
dynamic range needed for investigating detailed structures in the circumstellar
material. We present dramatic new images of NGC 7027 that have led to a new
understanding of the structure in this important planetary nebula. The central
star is clearly revealed, providing near-infrared fluxes that are used to
directly determine the stellar temperature very accurately (T = 198,000 K). It
is found that the photodissociation layer as revealed by near-infrared
molecular hydrogen emission is very thin, and is biconical in shape. The
interface region is structured and filamentary, suggesting the existence of
hydrodynamic instabilities. We discuss evidence for the presence of one or more
highly collimated, off-axis jets that might be present in NGC 7027. The
evolutionary future of NGC 7027 is discussed.

</DOC>
<DOC>
<DOCNO> 40595 </DOCNO>
A new limit on the permanent electric dipole moment of ^{199}Hg


  We present the first results of a new search for a permanent electric dipole
moment of the ^{199}Hg atom using a UV laser. Our measurements give d(Hg)= -
(1.06 +/- 0.49 +/- 0.40) 10^{-28} e cm. We interpret the result as an upper
limit |d(Hg)| < 2.1 10^{-28} e cm (95% C.L.), which sets new constraints on
theta_{QCD}, chromo-EDMs of the quarks, and CP violation in Supersymmetric
models.

</DOC>
<DOC>
<DOCNO> 116474 </DOCNO>
A microscopic derivation of Special Relativity: simple harmonic


  The starting point of the theory of Special Relativity$^1$ is the Lorentz
transformation, which in essence describes the lack of absolute measurements of
space and time. These effects came about when one applies the Second Relativity
Postulate to inertial observers. Here I demonstrate that there is a very
elegant way of explaining how exactly nature enforces Special Relativity, which
compels us to conclude that Einstein's great theory has already revealed
quantization of space and time. The model proposes that microscopically the
structure of space-time is analogous to a crystal which consists of lattice
points or `tickmarks' (for measurements) connected by identical `elastic
springs'. When at rest the `springs' are at their natural states. When set in
motion and used to measure objects at rest, however, the lattice effectively
vibrates in a manner described by Einstein's theory of the heat capacity of
solids, with consequent widening of the `tickmarks' because the
root-mean-square separation now increases. I associate a vibration temperature
$T$ with the speed of motion $v$ via the fundamental postulate of this theory,
viz. the relation $\frac{v^2}{c^2} = e^{-\frac{\epsilon}{kT}}$ where $\epsilon$
is a quantum of energy of the lattice harmonic oscillator. A moving observer
who measures distances with such a vibrating lattice obtains results which are
precisely those given by the Lorentz transformation. Apart from its obvious
beauty, this approach provides many new prospects in understanding space and
time. For example, a consequence of the model is that space-time, like mass,
can in principle be converted to energy.

</DOC>
<DOC>
<DOCNO> 102102 </DOCNO>
Hilbert schemes, polygraphs, and the Macdonald positivity conjecture


  We study the isospectral Hilbert scheme X_n, defined as the reduced fiber
product of C^2n with the Hilbert scheme H_n of points in the plane, over the
symmetric power S^n C^2. We prove that X_n is normal, Cohen-Macaulay, and
Gorenstein, and hence flat over H_n. We derive two important consequences.
  (1) We prove the strong form of the "n! conjecture" of Garsia and the author,
giving a representation-theoretic interpretation of the Kostka-Macdonald
coefficients K_{lambda,mu}(q,t). This establishes the Macdonald positivity
conjecture, that K_{lambda,mu}(q,t) is always a polynomial with non-negative
integer coefficients.
  (2) We show that the Hilbert scheme H_n is isomorphic to the Hilbert scheme
of orbits C^2n//S_n, in such a way that X_n is identified with the universal
family over C^2n//S_n.

</DOC>
<DOC>
<DOCNO> 71101 </DOCNO>
Neutrino mass spectrum and lepton mixing


  The program of reconstruction of the neutrino mass and flavor spectrum is
outlined and the present status of research is summarized. We describe the role
of future solar and atmospheric neutrino experiments, detection of the Galactic
supernovae and double beta decay searches in accomplishing this program. The
LSND result and four neutrino mass spectra are considered in connection with
recent searches for the sterile components in the solar and atmospheric
neutrino fluxes.

</DOC>
<DOC>
<DOCNO> 121756 </DOCNO>
Hard X-ray emission from IC443: evidence for a shocked molecular clump?


  We report BeppoSAX observations of spatially resolved hard X-ray emission
from IC 443, a supernova remnant interacting with a molecular cloud. The
emission is shown to come from two localized features spatially correlated with
bright molecular emission regions. Both hard X-ray features have soft X-ray
counterparts, in one case shifted by ~ 2 arcmin toward the remnant interior.
The spectra of X-ray emission from both isolated features have photon index ~2
in the MECS regime. The emission detected from the remnant with PDS detector
extends up to 100 keV. We discuss the observed properties of the hard X-ray
features in relation to non-thermal emission from shocked molecular clumps and
pulsar wind nebula.

</DOC>
<DOC>
<DOCNO> 151447 </DOCNO>
Fuzzy Cosets and their Gravity Duals


  Dp-branes placed in a certain external RR (p+4)-form field expand into a
transverse fuzzy two-sphere, as shown by Myers. We find that by changing the
(p+4)-form background other fuzzy cosets can be obtained. Three new examples,
S^2 X S^2, CP^2 and SU(3)/(U(1) X U(1)) are constructed. The first two are
four-dimensional while the last is six-dimensional. The dipole and quadrupole
moments which result in these configurations are discussed. Finally, the
gravity backgrounds dual to these vacua are examined in a leading order
approximation. These are multi-centered solutions containing (p+4)- or
(p+6)-dimensional brane singularities.

</DOC>
<DOC>
<DOCNO> 101468 </DOCNO>
Kauffman Monoids


  This paper gives a self-contained and complete proof of the isomorphism of
freely generated monoids extracted from Temperley-Lieb algebras with monoids
made of Kauffman's diagrams.

</DOC>
<DOC>
<DOCNO> 10165 </DOCNO>
Double Phase Transitions in Magnetized Spinor Bose-Einstein Condensation


  It is investigated theoretically that magnetized Bose-Einstein condensation
(BEC) with the internal (spin) degrees of freedom exhibits a rich variety of
phase transitions, depending on the sign of the interaction in the spin
channel. In the antiferromagnetic interaction case there exist always double
BEC transitions from single component BEC to multiple component BEC. In the
ferromagnetic case BEC becomes always unstable at a lower temperature, leading
to a phase separation. The detailed phase diagram for the temperature vs the
polarization, the spatial spin structure, the distribution of non-condensates
and the excitation spectrum are examined for the harmonically trapped systems.

</DOC>
<DOC>
<DOCNO> 71730 </DOCNO>
Degeneracy Symmetry Of Baryon Spectra


  We present a data-supported new interpretation of the Rarita-Schwinger fields
which reveals a well-defined pattern in the masses, spins, and parities of the
N-, Delta -, and Lambda -hyperon excitations and which allows to probe the
scale of the chiral phase transition for baryons. The degeneracy symmetry of
the baryonic spectra emerges to be Isospin(x)Space- Time.

</DOC>
<DOC>
<DOCNO> 151535 </DOCNO>
Seiberg-Witten curves for elliptic models


  Four-dimensional N=2 gauge theories may be obtained from configurations of
D-branes in type IIA string theory. Unitary gauge theories with two-index
representations, and orthogonal and symplectic gauge theories, are constructed
from configurations containing orientifold planes. Models with two orientifold
planes imply a compact dimension, and correspond to elliptic models. Lifting
these configurations to M-theory allows one to derive the Seiberg-Witten curves
for these gauge theories. We describe how the Seiberg-Witten curves,
necessarily of infinite order, are obtained for these elliptic models. These
curves are used to calculate the instanton expansion of the prepotential; we
explicitly find the one-instanton prepotential for all the elliptic models
considered.

</DOC>
<DOC>
<DOCNO> 9469 </DOCNO>
Pulling Pinned Polymers and Unzipping DNA


  We study a class of micromanipulation experiments, exemplified by the pulling
apart of the two strands of double-stranded DNA (dsDNA). When the pulling force
is increased to a critical value, an ``unzipping'' transition occurs. For
random DNA sequences with short-ranged correlations, we obtain exact results
for the number of monomers liberated and the specific heat, including the
critical behavior at the transition. Related systems include a random
heteropolymer pulled away from an adsorbing surface and a vortex line in a type
II superconductor tilted away from a fragmented columnar defect.

</DOC>
<DOC>
<DOCNO> 117445 </DOCNO>
Sunyaev-Zeldovich effect from hydrodynamical simulations: maps and low


  We use moving mesh hydrodynamical simulations to make maps of
Sunyaev-Zeldovich effect. We present these maps for several cosmological models
and explore their lowest moments. We find that the first moment, the mean
Compton $y$ parameter, is typically between $1-2\times 10^{-6}$ for cluster
abundance normalized models, the lower value corresponding to the high density
models, and scales as $\sigma_8^{3-4}$. Rms fluctuations at 10' scale have an
amplitude $ \Delta T/T \sim 1-3 \times 10^{-6}$ in the Rayleigh-Jeans regime.
The amplitude of the power spectrum strongly depends on the power spectrum
normalization and scales as $\sigma_8^{6-9}$. On smaller scales ($l>1000$) the
spectrum is dominated by halos below $10^{13}M_{\sun}$ and so is sensitive to
the thermal history of galactic halo gas. On larger scales ($l<1000$) the power
spectrum is less sensitive to nongravitational energy injection, but becomes
very noisy, with large field to field variations in the power spectrum caused
by rare bright sources in the maps, which dominate in the spectrum over the
large scale structure correlations. Cross-correlation power spectrum with weak
lensing or projected galaxy distribution is significant and the
cross-correlation coefficient is around 0.5 over a wide range of scales.
Comparison with Press-Schechter predictions gives very good agreement for all
the statistics, indicating that there is no significant contribution to SZ from
non-virialized structures. The one point distribution function shows clear
deviations from gaussianity and can be well-approximated as log-normal on small
scales.

</DOC>
<DOC>
<DOCNO> 122156 </DOCNO>
Effects of Preheating on X-ray Scaling Relations in Galaxy Clusters


  The failure of purely gravitational models of X-ray cluster formation to
reproduce basic observed properties of the local cluster population suggests
the need for one or more additional physical processes operating on the
intracluster medium (ICM). We present results from 84 moderate resolution gas
dynamic simulations designed to systematically investigate the effects of
preheating - an initially elevated ICM adiabat - on the resultant, local X-ray
size-temperature, luminosity-temperature and ICM mass-temperature relations.
Seven sets of twelve simulations are performed for a LambdaCDM cosmology, each
set characterized by a different initial entropy level S_i. The slopes of the
observable relations steepen monotonically as S_i is increased. Observed slopes
for all three relations are reproduced by models with S_i: 55-150 keV cm^2,
levels that compare favorably to empirical determinations of core ICM entropy
by Lloyd-Davies, Ponman & Cannon. The redshift evolution for the case of a
locally successful model with S_i = 106 keV cm^2 is presented. At temperatures
kT > 3 keV, little or no evolution in physical isophotal sizes or bolometric
luminosities is expected to z < 1. The ICM mass at fixed T is lower at higher z
as expected in the canonical evolution model. ICM mass fractions show a mild T
dependence. Clusters with T > 3 keV contain ICM mass fractions depressed by
modest amounts (< 25%) below the cosmic mean baryon fraction Omega_b/Omega_m;
hot clusters subject to preheating remain good tracers of the cosmic mix of
clustered mass components.

</DOC>
<DOC>
<DOCNO> 71383 </DOCNO>
Q^2 evolution of parton distributions at small x


  We investigate the Q^2 evolution of parton distributions at small x values,
obtained in the case of flat initial conditions. The results are in excellent
agreement with deep inelastic scattering experimental data from HERA.

</DOC>
<DOC>
<DOCNO> 102766 </DOCNO>
Invitation to higher local fields, Part I, section 1: Higher dimensional


  Basic concepts of higher local fields and topologies on their additive and
multiplicative groups are introduced.

</DOC>
<DOC>
<DOCNO> 99524 </DOCNO>
Polytopes for Crystallized Demazure Modules and Exremal Vectors


  We give a parametrization for crystal bases of Demazure modules as a set of
lattice points in some convex polytope and we also describe explicitly the
extremal vectors as solutions of some system of linear equations.

</DOC>
<DOC>
<DOCNO> 68665 </DOCNO>
Measurement of the gluon PDF at small x with neutrino telescopes


  We analyze the possibility that neutrino telescopes may provide an
experimental determination of the slope lambda of the gluon distribution in the
proton at momentum fractions x smaller than the accelerator reach. The method
is based on a linear relation between lambda and the spectral index (slope) of
the down-going atmospheric muon flux above 100 TeV, for which there is no
background. Considering the uncertainties in the charm production cross section
and in the cosmic ray composition, we estimate the error on the measurement of
lambda through this method, excluding the experimental error of the telescopes,
to be ~ +/- 0.2

</DOC>
<DOC>
<DOCNO> 83094 </DOCNO>
One Complexity Theorist's View of Quantum Computing


  The complexity of quantum computation remains poorly understood. While
physicists attempt to find ways to create quantum computers, we still do not
have much evidence one way or the other as to how useful these machines will
be. The tools of computational complexity theory should come to bear on these
important questions. Quantum computing often scares away many potential
researchers from computer science because of the apparent background need in
quantum mechanics and the alien looking notation used in papers on the topic.
This paper will give an overview of quantum computation from the point of view
of a complexity theorist. We will see that one can think of BQP as yet another
complexity class and study its power without focusing on the physical aspects
behind it.

</DOC>
<DOC>
<DOCNO> 122868 </DOCNO>
Populating a cluster of galaxies - I. Results at z=0


  We simulate the assembly of a massive rich cluster and the formation of its
constituent galaxies in a flat, low-density universe. Our most accurate model
follows the collapse, the star-formation history and the orbital motion of all
galaxies more luminous than the Fornax dwarf spheroidal, while dark halo
structure is tracked consistently throughout the cluster for all galaxies more
luminous than the SMC. Within its virial radius this model contains about 2.0e7
dark matter particles and almost 5000 distinct dynamically resolved galaxies.
Simulations of this same cluster at a variety of resolutions allow us to check
explicitly for numerical convergence both of the dark matter structures
produced by our new parallel N-body and substructure identification codes, and
of the galaxy populations produced by the phenomenological models we use to
follow cooling, star formation, feedback and stellar aging. This baryonic
modelling is tuned so that our simulations reproduce the observed properties of
isolated spirals outside clusters. Without further parameter adjustment our
simulations then produce a luminosity function, a mass-to-light ratio,
luminosity, number and velocity dispersion profiles, and a morphology-radius
relation which are similar to those observed in real clusters. In particular,
since our simulations follow galaxy merging explicitly, we can demonstrate that
it accounts quantitatively for the observed cluster population of bulges and
elliptical galaxies.

</DOC>
<DOC>
<DOCNO> 118104 </DOCNO>
X-Ray Wakes in Abell 160


  `Wakes' of X-ray emission have now been detected trailing behind a few (at
least seven) elliptical galaxies in clusters. To quantify how widespread this
phenomenon is, and what its nature might be, we have obtained a deep (70 ksec)
X-ray image of the poor cluster Abell 160 using the ROSAT HRI. Combining the
X-ray data with optical positions of confirmed cluster members, and applying a
statistic designed to search for wake-like excesses, we confirm that this
phenomenon is observed in galaxies in this cluster. The probability that the
detections arise from chance is less than 0.0038. Further, the wakes are not
randomly distributed in direction, but are preferentially oriented pointing
away from the cluster centre. This arrangement can be explained by a simple
model in which wakes arise from the stripping of their host galaxies'
interstellar media due to ram pressure against the intracluster medium through
which they travel.

</DOC>
<DOC>
<DOCNO> 120701 </DOCNO>
Atomic data from the Iron Project XLV. Relativistic transition


  The Breit-Pauli R-matrix method developed under the Iron Project has been
used to obtain extensive sets of oscillator strengths and transition
probabilities for dipole allowed and intercombination fine structure
transitions in carbon like ions, Ar XIII and Fe XXI. The complete set consists
of 1274 fine structure bound energy levels and 198,259 oscillator strengths for
Ar XIII, and 1611 bound levels and 300,079 oscillator strengths for Fe XXI.
These correspond to levels of total angular momenta of 0 <= J <= 7 of even and
odd parities formed from total spin of 2S+1=5,3,1, and orbital angular momenta
0 <= L <= 9 with n <= 10, 0 <= l <= 9 for each ion. The relativistic effects
are included in the Breit-Pauli approximation. The close coupling wavefunction
expansion for each ion is represented by the lowest 15 fine structure levels of
target configuations, 2s2.2p, 2s.2p2 and 2p3. The energy levels are identified
spectroscopically using a newly developed identification procedure. The
procedure also makes a correspondence between the fine strucure energy levels
and LS terms. This provides the check for completeness of the calculated
levels. Comparison is made of the present energies and the f-values with the
available observed and theoretical values. Present transition probabilitis
agree very well with the relativistic atomic structure calculations of Mendoza
et al. for the intercombination transitions, 2s.2p3(5So)2 -
2s2.2p2(3P){1,2},(1D)2. This further indicates that the importance of the
neglected Breit interaction decreases with ion charge and constrains the
uncertainty in the present calculations to within 15% even for the weak
transitions.

</DOC>
<DOC>
<DOCNO> 170720 </DOCNO>
A quantum-copying machine for equatorial qubits


  Bu\v{z}ek and Hillery proposed a universal quantum-copying machine (UQCM)
(i.e., transformation) to analyze the possibility of cloning arbitrary states.
The UQCM copies quantum-mechanical states with the quality of its output does
not depend on the input. We propose a slightly different transformation to
analyze a restricted set of input states. We impose the conditions (I) the
density matrices of the two output states are the same, and that (II) the
distance between input density operator and the output density operators is
input state independent. Using Hilbert-Schmidt norm and Bures fidelity, we show
that our transformation can achieves the bound of the fidelity.

</DOC>
<DOC>
<DOCNO> 14115 </DOCNO>
The rejuvenation effect in the two-state random energy model


  Theoretical analyses of the random energy model with only two states and its
extension with a hierarchy of only two levels show that these models reproduce
out-of-equilibrium phenomena observed in experiments of glassy materials; the
rejuvenation effect (the chaos effect), i.e. the abrupt jump and subsequent
relaxation of the out-of-phase susceptibility as if the system rejuvenates when
the temperature is lowered, and the power-law relaxation of the two-time
correlation function. Our results suggest that also in an assembly of small
systems with relaxation times distributed broadly some of these interesting
out-of-equilibrium phenomena can be observed.

</DOC>
<DOC>
<DOCNO> 68447 </DOCNO>
Kaon-baryon coupling constants in the QCD sum rule approach


  We improve our previous QCD sum rule calculation on G(KN\Lambda) and
G(KN\Sigma) coupling constants by including the contributions from higher
dimensional condensates, <\bar{q} g_s \sigma \cdot G q> and <\bar{q}q>
<(\alpha_s /\pi) G^2>, in the OPE. It is found that the contribution of these
condensates is non-negligible compared to that of the quark condensates. Using
a best-fit analysis we find |G(KN\Lambda)| = 2.49 $\pm$ 1.25 and |G(KN\Sigma)|
= 0.395 $\pm$ 0.377.

</DOC>
<DOC>
<DOCNO> 39892 </DOCNO>
Hadron Energy Reconstruction for the ATLAS Barrel Prototype Combined


  Hadron energy reconstruction for the Atlas barrel prototype combined
calorimeter, consisting of the lead-liquid argon electromagnetic part and the
iron-scintillator hadronic part, in the framework of the non-parametrical
method has been fulfilled. This method uses only the known e/h ratios and the
electron calibration constants and does not require the determination of any
parameters by a minimization technique and can be used for the fast energy
reconstruction in the first level trigger. The obtained reconstruction of the
mean values of energies is within $\pm 1%$ and the fractional energy resolution
is $[(58\pm3)% \sqrt{GeV}/\sqrt{E}+(2.5\pm0.3)%]\oplus (1.7\pm0.2) GeV/E$. The
obtained value of the e/h ratio for electromagnetic compartment of the combined
calorimeter is $1.74\pm0.04$ and agrees with the prediction that $e/h > 1.7$
for this electromagnetic calorimeter. The results of the study of the
longitudinal hadronic shower development are presented. The data have been
taken in the H8 beam line of the CERN SPS using pions of 10 -- 300 GeV.

</DOC>
<DOC>
<DOCNO> 8487 </DOCNO>
Crossover from classical to random-field critical exponents in As-doped


  Using birefringence techniques we have measured the critical exponents beta,
gamma, and delta in As-doped TbVO4, a structural realization of the
random-field Ising model where random strain fields are introduced by V-As size
mismatch. For pure TbVO4 we observe the expected classical critical exponents,
while for a mixed sample with 15% As concentration our results are beta=0.31
+/-0.03, gamma=1.22 +/-0.07, and delta=4.2 +/-0.7. These values are consistent
with the critical exponents for the short range pure Ising model in three
dimensions in agreement with a prediction by Toh. The susceptibility data
showed a crossover with temperature from classical to random field critical
behaviour.

</DOC>
<DOC>
<DOCNO> 118817 </DOCNO>
Radio Emission from GRO J1655-40 during the 1994 Jet Ejection Episodes


  We report multifrequency radio observations of GRO J1655-40 obtained with the
Australia Telescope Compact Array, the Molonglo Observatory Synthesis Telescope
and the Hartebeesthoek Radio Astronomy Observatory at the time of the major
hard X-ray and radio outbursts in 1994 August-September. The radio emission
reached levels of the order of a few Jy and was found to be linearly polarized
by up to 10%, indicating a synchrotron origin. The light curves are in good
agreement with those measured with the VLA, but our closer time sampling has
revealed two new short-lived events and significant deviations from a simple
exponential decay. The polarization data show that the magnetic field is well
ordered and aligned at right angles to the radio jets for most of the
monitoring period. The time evolution of the polarization cannot be explained
solely in terms of a simple synchrotron bubble model, and we invoke a hybrid
`core-lobe' model with a core which contributes both synchrotron and free-free
emission and `lobes' which are classical synchrotron emitters.

</DOC>
<DOC>
<DOCNO> 120611 </DOCNO>
On the Abundance Gradient of the Galactic Disk


  Estimates of the gas temperature in planetary nebulae obtained from the [O
III] emission line ratio and from the Balmer discontinuity indicate differences
reaching up to 6000 K (Liu and Danziger 1993). The [O III] temperature is
commonly used to obtain the ionic fractions of highly ionized ions,
particularly the O++ and Ne++ ions when using the empirical method to calculate
the elemental abundances of photoionized gas from the observed emission line
intensities. However, if the gas temperature is overestimated, the elemental
abundances may be underestimated, in particular, it may lead to an uncorrect
elemental abundance gradient of the Galaxy, usually used as a constraint for
the chemical evolution models. Using Monte Carlo simulations, we calculate the
systematic error, introduced in the abundance gradient obtained from planetary
nebulae by an overestimation of the gas temperature. The results indicate that
the abundance gradient in the Galaxy should be steeper than previously assumed.

</DOC>
<DOC>
<DOCNO> 67652 </DOCNO>
Non-leptonic hyperon weak decays in the Skyrme model revisited


  Non-leptonic hyperon weak decays are investigated in the SU(3) Skyrme model.
We use a collective coordinate scheme, following the approach in which the
symmetry breaking terms in the strong effective action are diagonalized
exactly. To describe the weak interactions we use an octet dominated weak
effective lagrangian that leads to a good description of the known 2\pi and
3\pi kaon decays. We show that the observed S-wave decays are reasonably well
reproduced in the model. On the other hand, our calculated P-wave amplitudes do
not agree with the empirical ones even though both pole and contact
contributions to these amplitudes are properly taken into account. Finally, an
estimate of the non-octet contributions to the decay amplitudes is presented.

</DOC>
<DOC>
<DOCNO> 121902 </DOCNO>
General Relativistic Collapse of Neutron Stars to Strange Stars: A


  It is known that Neutron Stars may be converted into more compact Strange
Stars (SS) on capture/formation of a ``seed'' of strange matter. It is also
known that the binding energy of the nascent hot SS is likely to be radiated as
$\nu -\bar\nu$s so that an electromagnetic pair fireball (FB) may be created by
neutrino annihilation. And already this process has been considered as a
probable source of Gamma Ray Bursts (GRB) by several authors, the most notable
of which is due to Cheng & Dai (PRL, 77, 1210, 1996). They mentioned that this
process may generate a FB luminosity (outside the neutrinosphere) of 10**(49)
erg. But we point out here that a SS is a relativistic object with surface
gravitation z=0.5. Accordingly, we present here a Relativistic Model of this
process, and show that, for a massive SS with M=2 solar mass, one may explain a
GRB energy of ~ 10**(53) erg., which is 4 orders higher than previous
non-relativistic estimate. Further since the baryonic mass of the thin crust of
a strange star is negligible, this FB will generate an extremely relativistic
blast wave. Thus this process may be one of the viable routes for the genesis
of hitherto unexplained cosmic Gamma Ray Bursts. While some of the GRBs might
be beamed, many of them do not show any long term spectral break in their
afterglows and are likely to be quasi-spherical. A particular example is GRB
971214 for which estimated GRB energy is 3. 10**(53) erg. Our model may be
useful for understanding the genesis of such powerful and unexplained bursts.

</DOC>
<DOC>
<DOCNO> 102714 </DOCNO>
Numerical analyses of a quantum-theoretic eight-dimensional Yang-Mills


  This paper has been superseded by math-ph/0102032, "Bures geometry of the
three-level quantum systems. II".

</DOC>
<DOC>
<DOCNO> 170478 </DOCNO>
The Representation of Numbers by States in Quantum Mechanics


  The representation of numbers by tensor product states of composite quantum
systems is examined. Consideration is limited to k-ary representations of
length L and arithmetic modulo k^{L}. An abstract representation on an L fold
tensor product Hilbert space H^{arith} of number states and operators for the
basic arithmetic operations is described. Unitary maps onto a physical
parameter based tensor product space H^{phy} are defined and the relations
between these two spaces and the dependence of algorithm dynamics on the
unitary maps is discussed. The important condition of efficient implementation
by physically realizable Hamiltonians of the basic arithmetic operations is
also discussed.

</DOC>
<DOC>
<DOCNO> 13738 </DOCNO>
Random walks on hyperbolic groups and their Riemann surfaces


  We investigate invariants for random elements of different hyperbolic groups.
We provide a method, using Cayley graphs of groups, to compute the probability
distribution of the minimal length of a random word, and explicitly compute the
drift in different cases, including the braid group $B_3$. We also compute in
this case the return probability. The action of these groups on the hyperbolic
plane is investigated, and the distribution of a geometric invariant, the
hyperbolic distance, is given. These two invariants are shown to be related by
a closed formula.

</DOC>
<DOC>
<DOCNO> 120248 </DOCNO>
Dissipative Collapse of a Spherical Cluster of Gas Clouds


  With a view to understand the galaxy/star formation scenario, we investigate
the dissipative collapse of a spherical cluster of gas clouds with an isotropic
velocity distribution. The time scale for collapse to one tenth radius is
studied as a function of the collision time in the system. The scalar virial
equation is used to investigate the evolution of the size of the cluster. This
is supplemented with an evolution equation for the random kinetic energy. The
above system is numerically solved and the results analyzed. For large values
of the collision time we find that the time scale for collapse is proportional
to the collision time as expected. However for large values of the dissipation,
i.e. for small collision times, the collapse time shows a nonlinear dependence
on the collision time.

</DOC>
<DOC>
<DOCNO> 68692 </DOCNO>
Self-interacting Warm Dark Matter


  It has been shown by many independent studies that the cold dark matter
scenario produces singular galactic dark halos, in strong contrast with
observations. Possible remedies are that either the dark matter is warm so that
it has significant thermal motion or that the dark matter has strong self
interactions. We have combined these ideas to calculate the linear mass power
spectrum and the spectrum of cosmic microwave background (CMB) fluctuations for
self-interacting warm dark matter. Our results indicate that such models have
more power on small scales than is the case for the standard warm dark matter
model, with a CMB fluctuation spectrum which is nearly indistinguishable from
standard cold dark matter. This enhanced small-scale power may provide better
agreement with the observations than does standard warm dark matter.

</DOC>
<DOC>
<DOCNO> 122700 </DOCNO>
On the nature of the microquasar V4641 Sagittarii


  We present photometric and spectroscopic optical and near-infrared (NIR)
observations taken during the outburst on September 1999 of the source V4641
Sgr = SAX J1819.3-2525 (in'tzand et al., 2000) = XTE J1819-254 (Markwardt et
al., 1999). We show that our observations suggest a distance between 4 and 8
kpc, the spectral type of the companion star being constrained between B3 and
A2 V, making the system a High Mass X-ray Binary System (HMXB). In view of the
radio and optical/NIR observations, it is possible that the ejecta of the
source interacted with the surrounding medium of the source.

</DOC>
<DOC>
<DOCNO> 12038 </DOCNO>
Dimension dependence of the conductance distribution in the non-metallic


  We study numerically the form of the conductance distribution in the
non-metallic regime for (1) weakly disordered systems which become insulating
due to increase of the system length and (2) cubic d-dimensional systems, in
which localization occours due to the increase of the disorder strength. In the
three dimensional systems, we prove that the one-channel approximation of the
conductance in the insulating regime is not sufficient. Obtained statistics of
the conductance indicates that the one-parameter scaling holds also in the
strongly insulating regime.

</DOC>
<DOC>
<DOCNO> 122861 </DOCNO>
How astrophysical mean field dynamos can circumvent existing quenching


  Mean field dynamo theory is a leading candidate to explain the observed large
scale magnetic fields of galaxies and stars. However, controversy arises over
the extent of premature quenching by the backreaction of the growing field. We
distinguish between rapid mean field dynamo action, which is required by
astrophysical systems, and resistively limited action. We show how the flow of
magnetic helicity is important for rapid action. Existing numerical and
analytic work suggesting that mean field dynamos are prematurely quenched and
resistively limited include approximations or boundary conditions which
suppress the magnetic helicity flow from the outset. Thus they do not
unambiguously reveal whether real astrophysical mean field dynamos are
dynamically suppressed when the helicity flow is allowed. An outflow of
helicity also implies an outflow of magnetic energy and so active coronae or
winds should accompany mean field dynamos. Open boundaries alone may not be
sufficient for rapid dynamo action and the additional physics of buoyancy and
outflows may be required. Possible simulation approaches to test some of the
principles are briefly discussed. Some limitations of the ``Zeldovich
relation'' are also addressed.

</DOC>
<DOC>
<DOCNO> 70224 </DOCNO>
Gravitational Stability and Extra Timelike Dimensions


  Tachyonic Kaluza-Klein modes normally appear from the compactification of
extra timelike dimensions with scale $L$ and lead to some instabilities of
physical systems. We calculate the contribution of tachyonic gravitons to the
self energies of spherical massive bodies of radius $R$ and discuss their
possible gravitational stability. We find that some spherical bodies can be
stable at critical radii $R=2\pi L p$ for some positive integers $p$. We also
prove the generic property of massive bodies that for the range $0<R\leq\pi L$
the gravitational force due to the ordinary massless graviton exchange is
screened by the Kaluza-Klein mode exchange of tachyonic gravitons.

</DOC>
<DOC>
<DOCNO> 100016 </DOCNO>
Euler systems of K_2 of CM elliptic curves


  We construct certain systems of elements in K_2 of CM elliptic curves. When
the classnumber of the field of CM is 1, the image of this system under the
regulator map forms an Euler system in the sense of Rubin.

</DOC>
<DOC>
<DOCNO> 102295 </DOCNO>
Braided Near-group Categories


  A near-group category is an additively semisimple category with a product
such that all but one of the simple objects is invertible. We classify braided
structures on near-group categories, and give explicit numerical formulas for
their associativity and commutativity morphisms.

</DOC>
<DOC>
<DOCNO> 84844 </DOCNO>
Non-Abelian Magnetic Monopoles in a Background of Gravitation with


  The purpose of this paper is to study static solution configuration which
describes the magnetic monopoles in a scenary where the gravitation is coupled
with Higgs, Yang-Mills and fermions. We are looking for analysis of the energy
functional and Bogomol'nyi equations. The Einstein equations now take into
consideration the fermions' contribution for energy-momentum tensor. The
interesting aspect here is to verify that the fermion field gives a
contribution for non abelian magnetic field and for potential which minimise
the energy functional.

</DOC>
<DOC>
<DOCNO> 119316 </DOCNO>
Cosmic Intelligence and Black Holes


  The paper is devoted to a new direction in SETI. After a general discussion
of the field, the authors put forth the hypothesis that the black holes may
serve as a physical substratum for intelligent beings. This hypothesis is based
on four parallels between the brain-psyche system, on the one hand, and black
holes, on the other. (1) The descriptions of brain and psyche, in the system
brain-psyche, are complementary to each other, as descriptions by internal and
external observers of a black hole in Susskind-t'Hooft's schema. (2) There is
an aspect of the inner structure of a black hole in Kerr's model of the
rotating black hole that is isomorphic to the structure of the human subjective
domain in the psychological model of reflexion. (3) Both black holes and the
brain-psyche system have a facet which can be represented using thermodynamic
concepts. (4) The brain lends itself to a holographic description; as has been
recently demonstrated by Susskind, black holes can also be described
holographically. The authors speculate that the intelligent black holes can
generate other black holes by triggering creation of massive stars from which
new black holes arise after the stars' collapse. In addition, the authors
analyze certain strange phenomena related to the birth of young massive stars
which may or may not be connected with such a triggering.

</DOC>
<DOC>
<DOCNO> 119092 </DOCNO>
The first galaxies: structure and stellar populations


  The Hubble Deep Fields continue to be a valuable resource for studying the
distant universe, particularly at z>2 where their comoving volume becomes large
enough to encompass several hundred L* galaxies or their progenitors. Here I
present recent results from a near-infrared imaging survey of the HDF-North
with NICMOS, which provides structural and photometric information in the
optical rest frame (4000-5500A) for hundreds of ordinary galaxies at 2<z<3, and
which offers the means to search for still more distant objects at z>>5. Lyman
break galaxies at 2<z<3 are compact and often irregular in the NICMOS images;
ordinary Hubble sequence spirals and ellipticals seem to be largely absent at
these redshifts, and apparently reached maturity at 1<z<2. The Lyman break
galaxies have UV-optical spectral energy distributions like those of local
starburst galaxies. Population synthesis models suggest typical ages ~few x
10^8 years and moderate UV extinction (~1.2 mag at 1700A), but the constraints
are fairly weak and there may be considerable variety. Considering a near-IR
selected galaxy sample, there is little evidence for a significant number of
galaxies at z~3 that have been missed by UV-based Lyman break selection. Using
the well-characterized z~3 galaxy population as a point of reference, I
consider Lyman break galaxy candidates at 4.5<z<9, as well as one remarkable
object which might (or might not) be at z>12. The space density of UV-bright
galaxies in the HDF appears to thin out toward larger redshifts, although
surface brightness selection effects may play an important role.

</DOC>
<DOC>
<DOCNO> 7754 </DOCNO>
Excitation energies from time-dependent density functional theory using


  The role of the exchange-correlation potential and the exchange-correlation
kernel in the calculation of excitation energues from time-dependent density
functional theory is studied. Excitation energies of the He and Be atoms are
calculated, both from the exact ground-state Kohn-Sham potential, and from two
orbital-dependent approximations. These are exact exchange and self-interaction
corrected local density approximation (SIC-LDA), both calculated using the
Krieger-Li-Iafrate (KLI) approximation. For the exchange-correlation kernela,
three adiabatic approximations were tested: The local density approximation,
exact exchange, and SIC-LDA. The choice of the ground-state
exchange-correlation potential has the largest impact on the absolute position
of most excitation energies. In particular, orbital-dependent approximate
potentials result in a uniform shift of the transition energies to the Rydberg
states.

</DOC>
<DOC>
<DOCNO> 170352 </DOCNO>
Invariants of Elementary Observations


  As physics searches for invariants in observations, this paper looks for
invariants of probabilistic observation without assuming physical structure.
Structure emerges from the basic assumption of science that new information
shall lead to more accurate knowledge of the invariants. This leads to
statistically unique random variables for expressing observed information:
Complex probability amplitudes. Predictions are also just random variables
computed from observed data, and must become more accurate with more
observations as input. This singles out the quantum mechanical superposition
principle. The external conditions of a probabilistic experiment can themselves
be monitored at the most detailed level, resulting in observation of coicidence
probabilities. The invariants of any multi-coincidence experiment are the same
as those of a one-event experiment with the same number of possible outcomes.
An observable probability turns out to be controllable by two independent
experimental conditions, naturally parametrized as a direction in a
3-dimensional space. In summary, the probabilistic paradigm itself defines a
unique method of forming concepts and making predictions. The method appears
irrefutable within probability, because, whenever a prediction turns out wrong
the existence of an as yet unmonitored condition is postulated, and a formal
way to incoroporate it is shown. The Hilbert space formalism of quantum theory
seems to be isomorphic to this method.

</DOC>
<DOC>
<DOCNO> 101812 </DOCNO>
On the moduli space of the Schwarzenberger bundles


  By proving a particular case of a conjecture of Drezet, we show that a
component of the Maruyama scheme of the semi-stable sheaves on the projective
space $\PP^n$ of rank n and Chern polynomial $(1+t)^{n+2}$ is isomorphic to the
Kronecher moduli $N(n+1,2,n+2)$, for any odd n. In particular, such scheme
defines a smooth minimal compactification of the moduli space of the rational
normal curves in $\PP^n$, that generalizes the construction defined by G.
Ellinsgrud, R. Piene and S. Str{\o}mme in the case $n=3$.

</DOC>
<DOC>
<DOCNO> 85133 </DOCNO>
Quantization of Dirac fields in static spacetime


  On a static spacetime, the solutions of the Dirac equation are generated by a
time-independent Hamiltonian. We study this Hamiltonian and characterize the
split into positive and negative energy. We use it to find explicit expressions
for advanced and retarded fundamental solutions and for the propagator.
Finally, we use a fermion Fock space based on the positive/negative energy
split to define a Dirac quantum field operator whose commutator is the
propagator.

</DOC>
<DOC>
<DOCNO> 39716 </DOCNO>
First experimental test of Bell inequalities performed using a


  We report on the realisation of a new test of Bell inequalities using the
superposition of type I parametric down conversion produced in two different
non-linear crystals pumped by the same laser, but with different polarisation.
The produced state is non-maximally entangled. We discuss the advantages and
the possible developments of this configuration.

</DOC>
<DOC>
<DOCNO> 12687 </DOCNO>
Gravity-driven instability in a spherical Hele-Shaw cell


  A pair of concentric spheres separated by a small gap form a spherical
Hele-Shaw cell. In this cell an interfacial instability arises when two
immiscible fluids flow. We derive the equation of motion for the interface
perturbation amplitudes, including both pressure and gravity drivings, using a
mode coupling approach. Linear stability analysis shows that mode growth rates
depend upon interface perimeter and gravitational force. Mode coupling analysis
reveals the formation of fingering structures presenting a tendency toward
finger tip-sharpening.

</DOC>
<DOC>
<DOCNO> 8293 </DOCNO>
Quantum Systems Obeying to Generalized Exclusion-Inclusion Principle


  In this work is studied a many body system obeying to a generalized
Exclusion-Inclusion Principle (EIP) originated by collective effect, the
dynamics, in mean field approximation, being ruled by a nonlinear Schroedinger
equation. The EIP is introduced by a judicious generalization of the particle
current. By means of variational principle is obtained a canonical nonlinear
Schroedinger equation. We study the Lagrangian and Hamiltonian formulation. We
study the symmetries of the nonlinear Schroedinger equation obeying to EIP and
by means of Noether theorem we obtain and discuss conserved quantities.
Successively, EIP-Schroedinger equation is coupled in a minimal way to an
abelian gauge field which dynamics is described by the Maxwell-Chern-Simons
Lagrangian. We show that the anyonic statistic behavior ascribed to the system
by the Chern-Simons Lagrangian is not destroyed by the presence of EIP
potential. Finally, we study special solutions of the system. Applications on
the Bose-Einstein condensation and vortex-like solution in the picture of
Chern-Simons interaction are considered.

</DOC>
<DOC>
<DOCNO> 102333 </DOCNO>
Evolution of a model quantum system under time periodic forcing:


  We analyze the time evolution of a one-dimensional quantum system with an
attractive delta function potential whose strength is subjected to a time
periodic (zero mean) parametric variation $\eta(t)$. We show that for generic
$\eta(t)$, which includes the sum of any finite number of harmonics, the
system, started in a bound state will get fully ionized as $t\to\infty$. This
is irrespective of the magnitude or frequency (resonant or not) of $\eta(t)$.
There are however exceptional, very non-generic $\eta(t)$, that do not lead to
full ionization, which include rather simple explicit periodic functions. For
these $\eta(t)$ the system evolves to a nontrivial localized stationary state
which is related to eigenfunctions of the Floquet operator.

</DOC>
<DOC>
<DOCNO> 84527 </DOCNO>
Selected solutions of Einstein's field equations: their role in general


  Contents: 1) Introduction and a few excursions [A word on the role of
explicit solutions in other parts of physics and astrophysics. Einstein's field
equations. "Just so" notes on the simplest solutions: The Minkowski, de Sitter
and anti-de Sitter spacetimes. On the interpretation and characterization of
metrics. The choice of solutions. The outline] 2) The Schwarzschild solution
[Spherically symmetric spacetimes. The Schwarzschild metric and its role in the
solar system. Schwarzschild metric outside a collapsing star. The
Schwarzschild-Kruskal spacetime. The Schwarzschild metric as a case against
Lorentz-covariant approaches. The Schwarzschild metric and astrophysics] 3) The
Reissner- Nordstrom solution [Reissner-Nordstrom black holes and the question
of cosmic censorship. On extreme black holes, d-dimensional black holes, string
theory and "all that"] 4) The Kerr metric [Basic features. The physics and
astrophysics around rotating black holes. Astrophysical evidence for a Kerr
metric] 5) Black hole uniqueness and multi-black hole solutions 6) Stationary
axisymmetric fields and relativistic disks [Static Weyl metrics. Relativistic
disks as sources of the Kerr metric and other stationary spacetimes. Uniformly
rotating disks] 7) Taub-NUT space [A new way to the NUT metric. Taub-NUT
pathologies and applications] 8) Plane waves and their collisions
[Plane-fronted waves. New developments and applications. Colliding plane waves]
9) Cylindrical waves [Cylindrical waves and the asymptotic structure of
3-dimensional general relativity. Cylindrical waves and quantum gravity. 
Cylindrical waves: a miscellany] 10) On the Robinson-Trautman solutions 11) The
boost-rotation symmetric radiative spacetimes 12) The cosmological models
[Spatially homogeneous cosmologies. Inhomogeneous models] 13) Concluding
remarks

</DOC>
<DOC>
<DOCNO> 150892 </DOCNO>
Dirichlet Boundary Conditions in Generalized Liouville Theory toward a


  We consider bosonic noncritical strings as QCD strings and we present a basic
strategy to construct them in the context of Liouville theory. We show that
Dirichlet boundary conditions play important roles in generalized Liouville
theory. Specifically, they are used to stabilize the classical configuration of
strings and also utilized to treat tachyon condensation in our model. We point
out that Dirichlet boundary conditions for the Liouville mode maintains Weyl
invariance, if an appropriate condition is satisfied, in the background with a
(non-linear) dilaton.

</DOC>
<DOC>
<DOCNO> 11120 </DOCNO>
Quantum Brain?


  In order to create a novel model of memory and brain function, we focus our
approach on the sub-molecular (electron), molecular (tubulin) and
macromolecular (microtubule) components of the neural cytoskeleton. Due to
their size and geometry, these systems may be approached using the principles
of quantum physics. We identify quantum-physics derived mechanisms conceivably
underlying the integrated yet differentiated aspects of memory encoding/recall
as well as the molecular basis of the engram. We treat the tubulin molecule as
the fundamental computation unit (qubit) in a quantum-computational network
that consists of microtubules (MTs), networks of MTs and ultimately entire
neurons and neural networks.
        We derive experimentally testable predictions of our quantum brain
hypothesis and perform experiments on these.

</DOC>
<DOC>
<DOCNO> 101930 </DOCNO>
On the quantum super Virasoro algebra


  The quantum super-algebra structure on the deformed super Virasoro algebra is
investigated. More specifically we established the possibility of defining a
non trivial Hopf super-algebra on both one and two-parameters deformed super
Virasoro algebras.

</DOC>
<DOC>
<DOCNO> 122794 </DOCNO>
A superfluid He3 detector for direct dark matter search


  MACHe3 (MAtrix of Cells of superfluid He3) is a project of a new detector for
direct Dark Matter Search. The idea is to use superfluid He3 as a sensitive
medium. The existing device, the superfluid He3 cell, will be briefly
introduced. Then a description of the MACHe3 project will be presented, in
particular the background rejection and the neutralino event rate that may be
achieved with such a device.

</DOC>
<DOC>
<DOCNO> 11819 </DOCNO>
Comparison of Global and Local Adaptive Coordinates for Density


  A globally-adaptive curvilinear coordinate formalism is shown to be easily
convertible to a class of curvilinear transformations locally optimized around
atom sites by a few parameters. Parameter transferability is established for a
demanding test case, and the results of the two methods are shown to be
comparable. Computational efficiencies realized in the local method are
discussed.

</DOC>
<DOC>
<DOCNO> 13036 </DOCNO>
Scaling in a continuous time model for biological aging


  In this paper we consider a generalization to the asexual version of the
Penna model for biological aging, where we take a continuous time limit. The
genotype associated to each individual is an interval of real numbers over
which Dirac $\delta$--functions are defined, representing genetically
programmed diseases to be switched on at defined ages of the individual life.
We discuss two different continuous limits for the evolution equation and two
different mutation protocols, to be implemented during reproduction. Exact
stationary solutions are obtained and scaling properties are discussed.

</DOC>
<DOC>
<DOCNO> 13414 </DOCNO>
Crossing the coexistence line at constant magnetization


  Using Monte Carlo histogram methods, the microcanonical caloric curve is
computed for the Ising model in two and three dimensions with fixed
magnetization. Whereas the signatures of a first order phase transition are
clearly visible for large systems, intriguing finite size effects are revealed
for smaller system sizes. The behaviour of the caloric curve is studied in a
systematic way. Furthermore, results for the thermal stability of
three-dimensional droplets of minority spins inside the two-phase region are
presented. The effect of the percolation transition on the stability of these
droplets is discussed.

</DOC>
<DOC>
<DOCNO> 122656 </DOCNO>
MERLIN/VLA imaging of the gravitational lens system B0218+357


  Gravitational lenses offer the possibility of accurately determining the
Hubble parameter (H_0) over cosmological distances, and B0218+357 is one of the
most promising systems for an application of this technique. In particular this
system has an accurately measured time delay (10.5+/-0.4 d; Biggs et al. 1999)
and preliminary mass modelling has given a value for H_0 of 69 +13/-19
km/s/Mpc. The error on this estimate is now dominated by the uncertainty in the
mass modelling. As this system contains an Einstein ring it should be possible
to constrain the model better by imaging the ring at high resolution. To
achieve this we have combined data from MERLIN and the VLA at a frequency of 5
GHz. In particular MERLIN has been used in multi-frequency mode in order to
improve substantially the aperture coverage of the combined data set. The
resulting map is the best that has been made of the ring and contains many new
and interesting features. Efforts are currently underway to exploit the new
data for lensing constraints using the LensClean algorithm (Kochanek & Narayan
1992).

</DOC>
<DOC>
<DOCNO> 121303 </DOCNO>
Metal Abundances of Red Clump Stars in Open Clusters: I. NGC 6819


  We present an analysis of high dispersion spectra (R~40000) of three red
clump stars in the old open cluster NGC 6819. The spectra were obtained with
SARG, the high dispersion spectrograph of the Telescopio Nazionale Galileo. The
spectra were analyzed using both equivalent widths measured with an automatic
procedure, and comparisons with synthetic spectra. NGC 6819 is found to be
slightly metal-rich ([Fe/H]= +0.09 +/-0.03, internal error); there are no
previous high resolution studies to compare with. Most element-to-element
abundance ratios are close to solar; we find a slight excess of Si, and a
significant Na overabundance. Our spectra can also be used to derive the
interstellar reddening towards the cluster, by comparing the observed colours
with those expected from line excitation: we derive E(B-V)=0.14 +/-0.04, in
agreement with the most recent estimate for this cluster.

</DOC>
<DOC>
<DOCNO> 81003 </DOCNO>
Geometry of Reduced Supersymmetric 4D Yang-Mills Integrals


  We study numerically the geometric properties of reduced supersymmetric
non-compact SU(N) Yang-Mills integrals in D=4 dimensions, for N = 2,3, ..., 8.
We show that in the range of large eigenvalues of the matrices A^mu, the
original D-dimensional rotational symmetry is spontaneously broken and the
dominating field configurations become one-dimensional, as anticipated by
studies of the underlying surface theory. We also discuss possible implications
of our results for the IKKT model.

</DOC>
<DOC>
<DOCNO> 119510 </DOCNO>
H-beta Line Width and the UV-X-ray Spectra of Luminous AGN


  The width of the broad H-beta emission line is the primary defining
characteristic of the NLS1 class. This parameter is also an important component
of Boroson and Green's optical Eigenvector 1 (EV1), which links steeper soft
X-ray spectra with narrower H-beta emission, stronger H-beta blue wing,
stronger optical Fe II emission, and weaker [O III] lambda 5007. Potentially,
EV1 represents a fundamental physical process linking the dynamics of fueling
and outflow with the accretion rate. We attempted to understand these
relationships by extending the optical spectra into the UV for a sample of 22
QSOs with high quality soft-X-ray spectra, and discovered a whole new set of UV
relationships that suggest that high accretion rates are linked to dense gas
and perhaps nuclear starbursts. While it has been argued that narrow (BLR)
H-beta means low Black Hole mass in luminous NLS1s, the C IV, lambda 1549 and
Ly alpha emission lines are broader, perhaps the result of outflows driven by
their high Eddington accretion rates. We present some new trends of optical-UV
with X-ray spectral energy distributions. Steeper X-ray spectra appear
associated with stronger UV relative to optical continua, but the presence of
strong UV absorption lines is associated with depressed soft X-rays and redder
optical-UV continua.

</DOC>
<DOC>
<DOCNO> 9446 </DOCNO>
Critical behavior of a non-equilibrium interacting particle system


  First- and second-order temperature driven transitions are studied, in a
lattice gas driven by an oscillatory field. The short time dynamics study
provides upper and lower bounds for the first-order transition points obtained
using standard simulations. The difference between upper and lower bounds is a
measure for the strength of the first-order transition and becomes negligible
small for densities close to one half. In addition, we give strong evidence on
the existence of multicritical points and a critical temperature gap, the
latter induced by the anisotropy introduced by the driving field.

</DOC>
<DOC>
<DOCNO> 121518 </DOCNO>
Using Perturbative Least Action to Reconstruct the Local Group


  In this paper, we apply the Perturbative Least Action Method to model the
Local Group of galaxies for various Cosmological models. We show that though
the galaxy masses are theoretically good discriminators of $\Omega_M$ given
some observed MW and M31 separation and radial velocity, current estimates of
the masses are insufficient to make any cosmological claims. We then discuss
additional complications to expand this analysis.

</DOC>
<DOC>
<DOCNO> 118940 </DOCNO>
Stringent constraints on single-star evolution theory from masses and


  Which sample of objects can give strong constraints on single-star evolution
theory ? Whilst star cluster members share the same age and the same
metallicity, many questions (e.g. field stars contamination, stellar rotation,
presence of unresolved binaries) are difficult to clarify properly when using
their colour-magnitude diagram to compare with theoretical isochrones.
Alternatively, binary stars can be used to put constraints on theoretical
predictions. However, while the stellar mass is accurately known for some
sample of well-detached binary stars, their metallicities are often poorly
known. Then it appears that a better test could be obtained by combining both
advantages (well-detached binaries members of a star cluster). This idea is
applied in this work to binaries in the Hyades and one binary in the Cepheus
OB3 association to test the validity of independent sets of theoretical tracks.
A detailed comparison of theoretical vs. observational masses (and radii when
possible) is presented.

</DOC>
<DOC>
<DOCNO> 119906 </DOCNO>
Can we see a rotating gravitational lens?


  It is known that the rotation of a gravitational lens affects properties of
images. We consider an inverse problem: If the lens is dark, can we infer its
rotation from the observed images? We find that, up to the first order in the
gravitational constant G, a rotating lens is not distinguishable from a
non-rotating one. The quadrupole contribution to the deflection angle is also
calculated for a general, extended lens object.

</DOC>
<DOC>
<DOCNO> 169573 </DOCNO>
Bound entanglement and continuous variables


  We introduce the definition of generic bound entanglement for the case of
continuous variables. We provide some examples of bound entangled states for
that case, and discuss their physical sense in the context of quantum optics.
We rise the question of whether the entanglement of these states is generic. As
a byproduct we obtain a new many parameter family of bound entangled states
with positive partial transpose. We also point out that the ``entanglement
witnesses'' and positive maps revealing the corresponding bound entanglement
can be easily constructed.

</DOC>
<DOC>
<DOCNO> 119297 </DOCNO>
Temporal properties of flares in accretion disk coronae


  Using a non-linear Monte-Carlo code we investigate the radiative response of
an accretion disk corona system to static homogeneous flares. We model a flare
by a rapid (comparable to the light crossing time) energy dissipation in the
corona or the disk.
  If the flares originate from the disk, the coronal response to the soft
photon shots produces a strongly non-linear Comptonised radiation output, with
complex correlation/anti-correlations between energy bands. This behavior
strongly differs from those found with usual linear calculations.
 Thus any model for the rapid aperiodic variability of X-ray binaries invoking
a varying soft photon input as a source for the hard X-ray variability has to
take into account the coronal temperature response.
  On the other hand, if the flare is due to a violent heating of the corona,
when the perturbation time scale is of the order of a few corona light crossing
times, the shot spectrum evolves from hard to soft.
 This general trend is independent of the shot profile and geometry.
 We show that for short dissipation time, the time averaged spectra are
generally harder than in steady state situation. In addition, annihilation line
and high energy tails can be produced without need for non-thermal processes.

</DOC>
<DOC>
<DOCNO> 69947 </DOCNO>
Unitarity triangles and geometrical description of CP violation with


  We generalize the geometrical description of CP violation in the Standard
Model in terms of a unitarity triangle. For three left-handed Majorana
neutrinos CP violation in the lepton sector is determined by three unitarity
triangles. With three additional right-handed neutrinos 15 quadrangles are
required to characterize CP violation. We show the relation of the unitarity
polygons with physical observables.

</DOC>
<DOC>
<DOCNO> 116434 </DOCNO>
Patterns on liquid surfaces: cnoidal waves, compactons and scaling


  Localized patterns and nonlinear oscillation formation on the bounded free
surface of an ideal incompressible liquid are analytically investigated .
Cnoidal modes, solitons and compactons, as traveling non-axially symmetric
shapes are discused. A finite-difference differential generalized Korteweg-de
Vries equation is shown to describe the three-dimensional motion of the fluid
surface and the limit of long and shallow channels one reobtains the well known
KdV equation. A tentative expansion formula for the representation of the
general solution of a nonlinear equation, for given initial condition is
introduced on a graphical-algebraic basis. The model is useful in multilayer
fluid dynamics, cluster formation, and nuclear physics since, up to an overall
scale, these systems display liquid free surface behavior.

</DOC>
<DOC>
<DOCNO> 9643 </DOCNO>
Dynamics of deviations from the Gaussian state in a freely cooling


  The time dependence of deviations from the Gaussian state in a freely cooling
homogeneous system of smooth inelastically colliding spheres is investigated by
kinetic theory. We determine the full time dependence of the coefficients of an
expansion around the Gaussian state in Generalized Laguerre polynomials.
Approximating this system of equations to sixth order, we find that the
asymptotic state, where the mean energy T follows Haff's law with time
independent cooling rate, is reached within a few collisions per particle.
Two-dimensional molecular dynamics simulations confirm our results and show
exponential behavior in the high-energy tails.

</DOC>
<DOC>
<DOCNO> 120618 </DOCNO>
Conference Summary: Mapping the Hidden Universe


  Two curiously connected topics provided a novel focus for this meeting in
Guanajuato, Mexico, 22--29, February, 2000. Two days were devoted to
discussions of galaxy surveys deep into the Galactic plane and to modeling of
the distribution of matter that makes use of quasi-full-sky coverage. Then the
meeting turned its attention for four further days to a look at the Universe
from surveys based on HI selection. How distorted is the world view of the
optical chauvinist?

</DOC>
<DOC>
<DOCNO> 116290 </DOCNO>
Everyone can understand quantum mechanics


  We show that everyone can understand quantum mechanics, only if he rejects
the following prejudice, namely classical continuous motion (CCM) is the only
possible and objective motion of particles.

</DOC>
<DOC>
<DOCNO> 119052 </DOCNO>
Dark Matter Scaling Relations


  We establish the presence of a dark matter core radius, for the first time in
a very large number of spiral galaxies of all luminosities. Contrary to common
opinion we find that the sizes of these cores and the " DM core problem" are
bigger for more massive spirals. As a result the Burkert profile provides an
excellent mass model for dark halos around disk galaxies. Moreover, we find
that the spiral dark matter core densities $\rho_{0}$ and core radii $r_{0}$
lie in the same scaling relation $\rho_{0}=4.5\times 10^-2 (r_{0}/kpc)^{-2/3}
M_{\odot}pc^{-3}$ of dwarf galaxies with core radii upto ten times more
smaller.

</DOC>
<DOC>
<DOCNO> 40529 </DOCNO>
Limits on radiative decays of solar neutrinos from a measurement during


  A search for possible radiative decays of solar neutrinos with emission of
photons in the visible range was performed during the total solar eclipse of
August 11, 1999. Due to very bad weather conditions our two telescopes were
unable to collect useful data; fortunately we obtained several video camera
images from a local TV station. An analysis of the digitised images is
presented and limits on the lifetime for radiative decay are discussed.

</DOC>
<DOC>
<DOCNO> 70798 </DOCNO>
Double-logarithmic asymptotics of the electromagnetic form factors of


  The asymptotic behaviour of the electromagnetic form factors of the electron
and quark is obtained in the double-logarithmic approximation for Sudakov
kinematics, i.e. for the case that the value of the momentum transfer is much
greater than the mass of the particle.

</DOC>
<DOC>
<DOCNO> 68577 </DOCNO>
Isospin Breaking and $\omega$->$\pi\pi$ Decay


  We study $\omega\to\pi^+\pi^-$ decay up to including all orders of the chiral
expansion and one-loop level of mesons in formlism of chiral constituent quark
model. This G-parity forbidden decay is caused by $m_u\neq m_d$ and
electromagnetic interaction of mesons. We illustrate that in the formlism both
nonresonant contact interaction and $\rho$ resonance exchange contribute to
this process, and the contribution from $\rho$ resonance exchange is dominant.
We obtain that transition matrix element is
$<~\rho|H_{\rho\omega}|\omega>=[-(3956\pm 280)-(1697\pm 130)i]$MeV$^2$, and
isospin breaking parameter is $m_d-m_u=3.9\pm 0.22$MeV at energy scale $\mu\sim
m_\omega$.

</DOC>
<DOC>
<DOCNO> 101854 </DOCNO>
Discrete approximation of functionals with jumps and creases


  We prove a discrete approximation of functionals with jumps and creases.

</DOC>
<DOC>
<DOCNO> 116294 </DOCNO>
Inelastic semiclassical Coulomb scattering


  We present a semiclassical S-matrix study of inelastic collinear
electron-hydrogen scattering. A simple way to extract all necessary information
from the deflection function alone without having to compute the stability
matrix is described. This includes the determination of the relevant Maslov
indices. Results of singlet and triplet cross sections for excitation and
ionization are reported. The different levels of approximation -- classical,
semiclassical, and uniform semiclassical -- are compared among each other and
to the full quantum result.

</DOC>
<DOC>
<DOCNO> 119299 </DOCNO>
L483: A Protostar In Transition From Class 0 to Class I


  We present molecular-line observations toward the dense core in L483 and its
bipolar outflow powered by the Class 0 object IRAS 18148-0440. CO (carbon
monoxide) maps show that the outflow is well collimated and asymmetric, and
that its gas is warmer than the surrounding cloud by at least a factor of 2.
H2CO (formaldehyde) lines toward the outflow show prominent high-velocity wings
and evidence for an H2CO abundance enhancement of a factor of 20. At ambient
velocities, these lines show strong self-absorption and a brighter blue peak, a
characteristic signature of inward motions. Finally, and in contrast with the
outflows from other Class 0 objects, the CH3OH (methanol) lines in L483 do not
show high velocity wings, and no evidence for abundance enhancement is found in
this molecule or in SiO (silicon monoxide). Comparing the physical and chemical
properties of the outflow in L483 with those of other outflows from Class 0 and
Class I sources, we find that the L483 outflow is somewhat intermediate between
these types. This suggests that the L483 central source has already started its
transition between Class 0 and Class I, and that its mixed properties
illustrate how this transition occurs.

</DOC>
<DOC>
<DOCNO> 100769 </DOCNO>
Virasoro algebra and wreath product convolution


  We present a group theoretic construction of the Virasoro algebra in the
framework of wreath products. This can be regarded as a counterpart of a
geometric construction of Lehn in the theory of Hilbert schemes of points on a
surface.

</DOC>
<DOC>
<DOCNO> 71284 </DOCNO>
Brane World Scenario with m-form field: Stabilisation of Radion Modulus


  We consider (n + m + 1) dimensional bulk spacetime, containing flat (n + m -
1) dimensional parallel branes, with topology R^{n - 1} \times T^m. We assume
that the graviton and an m-form field are the only bulk fields and that the
m-form field has non vanishing components along the T^m directions only. We
then find that the m-form field, with suitable bulk and brane potentials, can
stabilise the radion modulus at the required value with no fine tuning. We find
self tuning solutions also.

</DOC>
<DOC>
<DOCNO> 170477 </DOCNO>
Measurement of quantum devices


  Maximum-likelihood estimation is applied to identification of an unknown
quantum mechanical process represented by a ``black box''. In contrast to
linear reconstruction schemes the proposed approach always yields physically
sensible results. Its feasibility is demonstrated using the Monte Carlo
simulations for the two-level system (single qubit).

</DOC>
<DOC>
<DOCNO> 151994 </DOCNO>
Unstable Solitons in Noncommutative Gauge Theory


  We find a class of exact solutions of noncommutative gauge theories
corresponding to unstable non-BPS solitons. In the two-dimensional euclidean
(or 2+1 dimensional lorentzian) U(1) theory we find localized solutions
carrying nonzero magnetic flux. In four euclidean dimensions we find non-BPS
solutions with the same Pontrjagin charge but greater energy than the usual
self-dual Yang-Mills instanton. We conjecture that these solutions and
generalizations thereof correspond to nonsupersymmetric configurations of
D-(p-2k) branes (or intersections thereof) in a D-p brane in the noncommutative
scaling limit of large B-field. In the particular case of a 0-brane on a
2-brane the analysis of small fluctuations reveals an infinite tower of states
which agrees exactly with that of the 0-2 CFT in the scaling limit. The
spectrum contains a tachyon, and we show explicitly that the endpoint of
tachyon condensation corresponds to the 0-brane dissolved in the 2-brane.

</DOC>
<DOC>
<DOCNO> 102350 </DOCNO>
Irreducible subfactors derived from Popa's construction for non-tracial


  For an inclusion of the form $\Bbb C\subseteq M_n(\Bbb C)$, where $M_n(\Bbb
C)$ is endowed with a state with diagonal weights $\lambda=(\lambda_1, ...,
\lambda_n)$, we use Popa's construction, for non-tracial states, to obtain an
irreducible inclusion of $II_1$ factors, $N^\lambda(Q)\subseteq M^\lambda(Q) $
of index $\sum \frac{1}{\lambda_i}$. $M^\lambda(Q)$ is identified with a
subfactor inside the centralizer algebra of the canonical free product state on
$Q\star M_N(\Bbb C)$. Its structure is described by ``infinite'' semicircular
elements as in \cite{Ra3}. The irreducible subfactor inclusions obtained by
this method are similar to the first irreducible subfactor inclusions, of index
in $[4,\infty)$ constructed in \cite {Po1}, starting with the Jones' subfactors
inclusion $R^s\subseteq R$, $s>4$. In the present paper, since the inclusion we
start with has a simpler structure, it is easier to control the algebra
structure of the subfactor inclusions.

</DOC>
<DOC>
<DOCNO> 117763 </DOCNO>
A Search for Sub-millisecond Pulsations in Unidentified FIRST and NVSS


  We have searched 92 unidentified sources from the FIRST and NVSS 1400 MHz
radio survey catalogs for radio pulsations at 610 MHz. The selected radio
sources are bright, have no identification with extragalactic objects, are
point-like and are more than 5% linearly polarized. Our search was sensitive to
sub-millisecond pulsations from pulsars with dispersion measures (DMs) less
than 500 pc cm-3 in the absence of scattering. We have detected no pulsations
from these sources and consider possible effects which might prevent detection.
We conclude that as a population, these sources are unlikely to be pulsars.

</DOC>
<DOC>
<DOCNO> 122222 </DOCNO>
X-ray Imaging Spectroscopy of Abell 1835


  We present detailed spatially-resolved spectroscopy results of the
observation of Abell 1835 using the European Photon Imaging Cameras (EPIC) and
the Reflection Grating Spectrometers (RGS) on the XMM-Newton observatory. Abell
1835 is a luminous ($10^{46}$ ergs ${s}^{-1}$), medium redshift ($z=0.2523$),
  X-ray emitting cluster of galaxies. The observations support the
interpretation that large amounts of cool gas are present in a multi-phase
medium surrounded by a hot ($kT_{e}$=8.2 keV) outer envelope. We detect O VIII
Ly$\alpha$ and two Fe XXIV complexes in the RGS spectrum. The emission measure
of the cool gas below $kT_{e}$=2.7 keV is much lower than expected from
standard cooling-flow models, suggesting either a more complicated cooling
process than simple isobaric radiative cooling or differential cold absorption
of the cooler gas.

</DOC>
<DOC>
<DOCNO> 40234 </DOCNO>
Chiral loops and a_0(980) exchange in \phi->\pi^0\eta\gamma


  The radiative $\phi\to\pi^0\eta\gamma$ decay is discussed emphasizing the
effects of the $a_0$(980) scalar resonance which dominates the high values of
the $\pi^0\eta$ invariant mass spectrum. In its lowest part, the proposed
amplitude coincides with the reliable and ChPT-inspired contribution coming
from chiral loops. The $a_0$(980) resonance is then incorporated exploiting the
complementarity between ChPT and the linear sigma model for this channel. The
recently reported experimental invariant mass distribution and branching ratio
can be satisfactorily accommodated in our framework. For the latter, a value of
$B(\phi\to\pi^0\eta\gamma)$ in the range $(0.75$--$0.95)\times 10^{-4}$ is
predicted.

</DOC>
<DOC>
<DOCNO> 70810 </DOCNO>
QCD coherence effects in high energy reactions with nuclei


  In this work, coherence effects in deep inelastic scattering (DIS) and in the
Drell-Yan (DY) process off nuclei are investigated, in particular nuclear
shadowing. The target rest frame and the color dipole formulation are employed.
Multiple scatterings are treated in Glauber-Gribov theory, which is modified to
include the nuclear form factor to all orders. Based on the mean coherence
length, which is defined in this work, it is estimated that gluon shadowing is
negligible at x_{Bj}>0.01. Parameter free calculations are compared to NMC and
E665 data for DIS and to E772 data for DY. In both cases, good agreement is
found. It is however not possible to reproduce the effect observed by HERMES.
For dileptons in proton-nucleus collisions at RHIC energies, considerable
shadowing for the whole x_F range is predicted. The influence of the nucleus on
the DY transverse momentum distribution is also studied. Furthermore, a new
parametrization of the dipole cross section is presented.

</DOC>
<DOC>
<DOCNO> 123128 </DOCNO>
A Balloon-borne Large Aperture Submillimeter Telescope


  A new generation of sub-orbital platforms will be operational in the next few
years. These new telescopes will operate from airborne and balloon-borne
platforms where the atmosphere is transparent enough to allow sensitive
measurements to be made in the submillimeter bands. The telescopes will take
advantage of state-of-the-art instrumentation including large format bolometer
arrays and spectrometers. Other papers in this volume will deal specifically
with the potential of these bands. In this paper will review the capabilities
the BLAST balloon-borne telescope.

</DOC>
<DOC>
<DOCNO> 169628 </DOCNO>
Physical model of Schrodinger's electron. Heisenberg convenient way for


  The object of this paper is to discuss the physical interpretation of quantum
behaviour of Schrodinger electron (SchEl) and bring to light on the cause for
the Heisenberg convenient operator way of its describing, using the
nonrelativistic quantum mechanics laws and its mathematical results. We
describe the forced stochastically diverse circular oscillation motion, created
by force of the electrical interaction of the SchEl's elementary electric
charge with the electric intensity of the resultant quantum electromagnetic
field of the existing StchVrtPhtns, as a solution of Abraham-Lorentz equation.
By dint of this equation we obtain that the smooth thin line of a classical
macro particle is rapidly broken of many short and disorderly orientated lines,
owing the continuous dispersion of the quantum micro particle (QntMicrPrt) on
the StchVrtPhtns. Between two successive scattering the centers of diverse
circular oscillations with stochastically various radii are moving along this
short disordered line. These circular oscillations lie within the flats,
perpendicular to same disordered short line, along which are moving its
centers. In a result of same forced circular oscillation motion the smooth thin
line of the LrEl is roughly spread and turned out into some cylindrically wide
path of the SchEl. Hence the dispersions of different dynamical parameters,
determining the state of the SchEl, which are results of its continuously
interaction with the resultant quantum electromagnetic field of the
StchVrtPhtns. The absence of the smooth thin line trajectory at the circular
oscilation moving of the QntMicrPrt forces us to use the matrix elements
(Fourier components) of its roughly spread wide cylindrical path for its
description.

</DOC>
<DOC>
<DOCNO> 9073 </DOCNO>
Direct correlation functions and bridge functions in additive


  A method to obtain (approximate) analytical expressions for the radial
distribution functions in a multicomponent mixture of additive hard spheres
that was recently introduced is used to obtain the direct correlation functions
and bridge functions in these systems. This method, which yields results
practically equivalent to the Generalized Mean Spherical Approximation and
includes thermodynamic consistency, is an alternative to the usual integral
equation approaches and requires as input only the contact values of the radial
distribution functions and the isothermal compressibility. Calculations of the
bridge functions for a binary mixture using the
Boubl\'{\i}k-Mansoori-Carnahan-Starling-Leland equation of state are compared
to parallel results obtained from the solution of the Percus-Yevick equation.
We find that the conjecture recently proposed by Guzm\'{a}n and del R\'{\i}o
(1998, {\em Molec. Phys.}, {\bf 95}, 645) stating that the zeros of the bridge
functions occur approximately at the same value of the shifted distance for all
pairs of interactions is at odds with our results. Moreover, in the case of
disparate sizes, even the Percus-Yevick bridge functions do not have this
property. It is also found that the bridge functions are not necessarily
non-positive.

</DOC>
<DOC>
<DOCNO> 122653 </DOCNO>
47 Tuc: The Spectroscopic Versus CMD Age Discrepancy


  We investigate current problems in obtaining reliable ages for old stellar
systems based on stellar population synthesis modelling of their integrated
spectra. In particular, we address the large ages derived for the globular
cluster 47 Tuc, which is at odds with its Color-Magnitude-Diagram (CMD) age.
Using a new age indicator, Hgamma_sigma<130, which is particularly effective at
breaking the degeneracy between age and metallicity, we confirm the discrepancy
between the spectroscopic age and the CMD age of 47 Tuc, in that the
spectroscopic age is much older. Nebular emission appears unlikely to be a
source for weakening the observed Balmer lines. We then explore a number of key
parameters affecting the temperature of Turn-Off stars, which are the main
contributors to the Balmer lines for old metal-rich stellar populations. We
find that alpha-enhanced isochrones with atomic diffusion included not only
provides a good fit to the CMD of 47 Tuc, but also leads to a spectroscopic age
in better agreement with the CMD age.

</DOC>
<DOC>
<DOCNO> 13362 </DOCNO>
Orbital polarons and ferromagnetic insulators in manganites


  We argue that in lightly hole doped perovskite-type Mn oxides the holes
(Mn$^{4+}$ sites) are surrounded by nearest neighbor Mn$^{3+}$ sites in which
the occupied $3d$ orbitals have their lobes directed towards the central hole
(Mn$^{4+}$) site and with spins coupled ferromagnetically to the central spin.
This composite object, which can be viewed as a combined orbital-spin-lattice
polaron, is accompanied by the breathing type (Mn$^{4+}$) and Jahn-Teller type
(Mn$^{3+}$) local lattice distortions. We present calculations which indicate
that for certain doping levels these orbital polarons may crystallize into a
charge and orbitally ordered ferromagnetic insulating state.

</DOC>
<DOC>
<DOCNO> 84312 </DOCNO>
Passivity and microlocal spectrum condition


  In the setting of vector-valued quantum fields obeying a linear wave-equation
in a globally hyperbolic, stationary spacetime, it is shown that the two-point
functions of passive quantum states (mixtures of ground- or KMS-states) fulfill
the microlocal spectrum condition (which in the case of the canonically
quantized scalar field is equivalent to saying that the two-point function is
of Hadamard form). The fields can be of bosonic or fermionic character. We also
give an abstract version of this result by showing that passive states of a
topological *-dynamical system have an asymptotic pair correlation spectrum of
a specific type.

</DOC>
<DOC>
<DOCNO> 151438 </DOCNO>
Position Measurement for a Relativistic Particle:


  Measurements of the position of a relativistic particle is considered in the
framework of the Restricted-Path-Integral (RPI) approach. The amplitude
describing such a measurement is shown to be exponentially small outside the
light cone of the space-time point corresponding to the measurement output, in
a qualitative agreement with the Hellwig and Kraus' postulate of relativistic
state reduction. Theory of the measurement including the probability
distribution for different measurement outputs is suggested. It is shown that
correct theory does not exist (for arbitrary initial states) if the error of
the measurement is less than the Compton length. The physical reason is that
the picture of measurement is destroyed in this case by pair creation.

</DOC>
<DOC>
<DOCNO> 13073 </DOCNO>
Correlated tunneling into a superconductor in a multiprobe hybrid


  We consider tunneling in a hybrid system consisting of a superconductor with
two or more probe electrodes which can be either normal metals or polarized
ferromagnets. In particular we study transport at subgap voltages and
temperatures. Besides Andreev pair tunneling at each contact, in multi-probe
structures subgap transport involves additional channels, which are due to
coherent propagation of two particles (electrons or holes), each originating
from a different probe electrode. The relevant processes are electron
cotunneling through the superconductor and conversion of two electrons stemming
from different probes in a Cooper pair. These processes are non-local and decay
when the distance between the pair of involved contacts is larger than the
superconducting coherence length. The conductance matrix of a the three
terminal hybrid structure is calculated. The multi-probe processes enhance the
conductance of each contact. If the contacts are magnetically polarized the
contribution of the various conduction channels may be separately detected.

</DOC>
<DOC>
<DOCNO> 8651 </DOCNO>
Kondo screening and exhaustion in the periodic Anderson model


  We investigate the paramagnetic periodic Anderson model using the dynamical
mean-field theory in combination with the modified perturbation theory which
interpolates between the weak and strong coupling limits. For the symmetric
PAM, the ground state is always a singlet state. However, as function of the
hybridization strength, a crossover from collective to local Kondo screening is
found. Reducing the number of conduction electrons, the local Kondo singlets
remain stable. The unpaired f-electrons dominate the physics of the system. For
very low conduction electron densities, a large increase of the effective mass
of the quasiparticles is visible, which is interpreted as the approach of the
Mott-Hubbard transition.

</DOC>
<DOC>
<DOCNO> 71720 </DOCNO>
Matrix Elements of Four-quark Operators Relevant to Lifetime Difference


  We extract the matrix elements of four quark operators O_{L,S} relevant to
the B_s and \bar B_s life time difference from QCD sum rules. We find the
vacuum saturation approximation works reasonably well, i.e., within 10%. We
discuss the implications of our results and compare them with the recent
lattice QCD determination.

</DOC>
<DOC>
<DOCNO> 151816 </DOCNO>
Auxiliary Field Formulation of Supersymmetric Nonlinear Sigma Models


  Two dimensional N=2 supersymmetric nonlinear sigma models on hermitian
symmetric spaces are formulated in terms of the auxiliary superfields. If we
eliminate auxiliary vector and chiral superfields, they give D- and F-term
constraints to define the target manifolds. The integration over auxiliary
vector superfields, which can be performed exactly, is equivalent to the
elimination of the auxiliary fields by the use of the classical equations of
motion.

</DOC>
<DOC>
<DOCNO> 170328 </DOCNO>
Universal simulation of Markovian quantum dynamics


  Although the conditions for performing arbitrary unitary operations to
simulate the dynamics of a closed quantum system are well understood, the same
is not true of the more general class of quantum operations (also known as
superoperators) corresponding to the dynamics of open quantum systems. We
propose a framework for the generation of Markovian quantum dynamics and study
the resources needed for universality. For the case of a single qubit, we show
that a single nonunitary process is necessary and sufficient to generate all
unital Markovian quantum dynamics, whereas a set of processes parametrized by
one continuous parameter is needed in general. We also obtain preliminary
results for the unital case in higher dimensions.

</DOC>
<DOC>
<DOCNO> 8555 </DOCNO>
Experimental Investigation of Resonant Activation


  We experimentally investigate the escape from a metastable state over a
fluctuating barrier of a physical system. The system is switching between two
states under electronic control of a dichotomous noise. We measure the escape
time and its probability density function as a function of the correlation rate
of the dichotomous noise in a frequency interval spanning more than 4 frequency
decades. We observe resonant activation, namely a minimum of the average escape
time as a function of the correlation rate. We detect two regimes in the study
of the shape of the escape time probability distribution: (i) a regime of
exponential and (ii) a regime of non-exponential probability distribution.

</DOC>
<DOC>
<DOCNO> 14003 </DOCNO>
Dark-Bright Solitons in Inhomogeneous Bose-Einstein Condensates


  We investigate dark-bright vector solitary wave solutions to the coupled
non-linear Schr\"odinger equations which describe an inhomogeneous two-species
Bose-Einstein condensate. While these structures are well known in non-linear
fiber optics, we show that spatial inhomogeneity strongly affects their motion,
stability, and interaction, and that current technology suffices for their
creation and control in ultracold trapped gases. The effects of controllably
different interparticle scattering lengths, and stability against
three-dimensional deformations, are also examined.

</DOC>
<DOC>
<DOCNO> 70970 </DOCNO>
Possible large mass effects in direct determination of the CKM elements


  We discuss the possibility that mass effects, beyond phase space, may have
substantial influence on the direct determination of $V_{tq}$ in decays of top
quarks. In principle, our results are valid both for singly produced top and
for $t {\bar t}$ pair production.

</DOC>
<DOC>
<DOCNO> 13690 </DOCNO>
Zeroth and Second Laws of Thermodynamics Simultaneously Questioned in


  Several models of quantum open systems are known at present to violate,
according to principles of the standard quantum theory of open systems, the
second law of thermodynamics. Here, a new and rather trivial model of another
type is suggested describing mechanism that violates, according to the same
principles, the zeroth and the second laws of thermodynamics simultaneously. Up
to a technically minor modification, the model resembles some models already
known, solved by standard means, and properly understood. Universal validity of
two basic principles of thermodynamics in strictly quantum situations is thus
simultaneously called in question.

</DOC>
<DOC>
<DOCNO> 102145 </DOCNO>
Spherical harmonic polynomials for higher bundles


  We give a method of decomposing bundle-valued polynomials compatible with the
action of the Lie group $Spin(n)$, where important tools are
$Spin(n)$-equivariant operators and their spectral decompositions. In
particular, the top irreducible component is realized as an intersection of
kernels of these operators.

</DOC>
<DOC>
<DOCNO> 71471 </DOCNO>
An effective field theory for collinear and soft gluons: heavy to light


  We construct the Lagrangian for an effective theory of highly energetic
quarks with energy Q, interacting with collinear and soft gluons. This theory
has two low energy scales, the transverse momentum of the collinear particles,
p_perp, and the scale p_perp^2/Q. The heavy to light currents are matched onto
operators in the effective theory at one-loop and the renormalization group
equations for the corresponding Wilson coefficients are solved. This running is
used to sum Sudakov logarithms in inclusive B -> X_s gamma and B -> X_u \ell nu
decays. We also show that the interactions with collinear gluons preserve the
relations for the soft part of the form factor for heavy to light decays found
by Charles et al., establishing these relations in the large energy limit of
QCD.

</DOC>
<DOC>
<DOCNO> 8543 </DOCNO>
Suppression and enhancement of the critical current in multiterminal


  We analyse the measured critical current $I_{m\text{}}$ in a mesoscopic
4-terminal S/N/S structure. The current through the S/N interface is shown to
consist not only of the Josephson component $I_{c}\sin \phi ,$ but also a
phase-coherent part $I_{sg}\cos \phi $ of the subgap current. The current
$I_{m}$ is determined by the both components $I_{c}$ and $I_{sg},$ and depends
in a nonmonotonic way on the voltage $V$ between superconductors and normal
reservoirs reaching a maximum at $V\cong \Delta /e$. The obtained theoretical
resultas are in qualitative agreement with recent experimental data.

</DOC>
<DOC>
<DOCNO> 152482 </DOCNO>
De-singularization by rotation


  We consider certain BPS supergravity solutions of string theory which have
singularities and we show that the singularity goes away when we add angular
momentum. These smooth solutions enable us to obtain {\it global} $AdS_3$ as
the near horizon geometry of a BPS brane system in an asymptotically flat
space.

</DOC>
<DOC>
<DOCNO> 71876 </DOCNO>
KNO scaling 30 years later


  KNO scaling, i.e. the collapse of multiplicity distributions P_n onto a
universal scaling curve manifests when P_n is expressed as the distribution of
the standardized multiplicity (n-c)/lambda with c and lambda being location and
scale parameters governed by leading particle effects and the growth of average
multiplicity. At very high energies, strong violation of KNO scaling behavior
is observed (p-pbar) and expected to occur (e+e-). This challenges one to
introduce novel, physically well motivated and preferably simple scaling rules
obeyed by high-energy data. One possibility what I find useful and which
satisfies the above requirements is the repetition of the original scaling
prescription (shifting and rescaling) in Mellin space, that is, for the
multiplicity moments' rank. This scaling principle is discussed here,
illustrating its capabilities both on model predictions and on real data.

</DOC>
<DOC>
<DOCNO> 116973 </DOCNO>
Study of Nonlinearities and Small Particle Losses in High Power Linac


  The conception of High Power Linac developed in Russian accelerator centres
is based on the use of independently phased SC resonators with quadrupole
lenses between them. The type and parameters of the resonators as well as
focusing structure are varied along the linac to optimise beam dynamics and the
characteristics of the linac. The beam evolution in the linac was studied by
simulation in 3D accelerating and focusing fields by computer code DYNAMION.
  The simulation includes all nonlinearities of external fields and space
charge forces. Estimations of particle losses in the beam based on analysis of
the spectral properties of particle trajectories were carried out.

</DOC>
<DOC>
<DOCNO> 83154 </DOCNO>
Message Classification in the Call Center


  Customer care in technical domains is increasingly based on e-mail
communication, allowing for the reproduction of approved solutions. Identifying
the customer's problem is often time-consuming, as the problem space changes if
new products are launched. This paper describes a new approach to the
classification of e-mail requests based on shallow text processing and machine
learning techniques. It is implemented within an assistance system for call
center agents that is used in a commercial setting.

</DOC>
<DOC>
<DOCNO> 83077 </DOCNO>
Uniform semantic treatment of default and autoepistemic logics


  We revisit the issue of connections between two leading formalisms in
nonmonotonic reasoning: autoepistemic logic and default logic. For each logic
we develop a comprehensive semantic framework based on the notion of a belief
pair. The set of all belief pairs together with the so called knowledge
ordering forms a complete lattice. For each logic, we introduce several
semantics by means of fixpoints of operators on the lattice of belief pairs.
Our results elucidate an underlying isomorphism of the respective semantic
constructions. In particular, we show that the interpretation of defaults as
modal formulas proposed by Konolige allows us to represent all semantics for
default logic in terms of the corresponding semantics for autoepistemic logic.
Thus, our results conclusively establish that default logic can indeed be
viewed as a fragment of autoepistemic logic. However, as we also demonstrate,
the semantics of Moore and Reiter are given by different operators and occupy
different locations in their corresponding families of semantics. This result
explains the source of the longstanding difficulty to formally relate these two
semantics. In the paper, we also discuss approximating skeptical reasoning with
autoepistemic and default logics and establish constructive principles behind
such approximations.

</DOC>
<DOC>
<DOCNO> 12861 </DOCNO>
Aperiodicity and Disorder - Does it Matter?


  The effects of an aperiodic order or a random disorder on phase transitions
in statistical mechanics are discussed. A heuristic relevance criterion based
on scaling arguments as well as specific results for Ising models with random
disorder or certain kinds of aperiodic order are reviewed. In particular, this
includes an exact real-space renormalization treatment of the Ising quantum
chains with coupling constants modulated according to substitution sequences,
related to a two-dimensional classical Ising model with layered disorder.

</DOC>
<DOC>
<DOCNO> 116409 </DOCNO>
Nature of Sonoluminescence: Noble Gas Radiation Excited by Hot Electrons


  We show that strong electric fields occurring in water near the surface of
collapsing gas bubbles because of the flexoelectric effect can provoke dynamic
electric breakdown in a micron-size region near the bubble and consider the
scenario of the SBSL. The scenario is: (i) at the last stage of incomplete
collapse of the bubble the gradient of pressure in water near the bubble
surface has such a value and sign that the electric field arising from the
flexoelectric effect exceeds the threshold field of the dynamic electrical
breakdown of water and is directed to the bubble center; (ii) mobile electrons
are generated because of thermal ionization of water molecules near the bubble
surface; (iii) these electrons are accelerated in ''cold'' water by the strong
electric fields; (iv) these hot electrons transfer noble gas atoms dissolved in
water to high-energy excited states and optical transitions between these
states produce SBSL UV flashes in the trasparency window of water; (v) the
breakdown can be repeated several times and the power and duration of the UV
flash are determined by the multiplicity of the breakdowns. The SBSL spectrum
is found to resemble a black-body spectrum where temperature is given by the
effective temperature of the hot electrons. The pulse energy and some other
characteristics of the SBSL are found to be in agreement with the experimental
data when realistic estimations are made.

</DOC>
<DOC>
<DOCNO> 102224 </DOCNO>
On Partitions of Goldbach's Conjecture


  An approximate formula for the partitions of Goldbach's Conjecture is derived
using Prime Number Theorem and a heuristic probabilistic approach. A strong
form of Goldbach's conjecture follows in the form of a lower bounding function
for the partitions of Goldbach's conjecture. Numerical computations suggest
that the lower and upper bounding functions for the partitions satisfy a simple
functional equation. Assuming that this invariant scaling property holds for
all even integer $n$, the lower and upper bounds can be expressed as simple
exponentials.

</DOC>
<DOC>
<DOCNO> 118741 </DOCNO>
On the sources of the late integrated Sachs-Wolfe effect


  In some scenarios, the peculiar gravitational potential of linear and mildly
nonlinear structures depends on time and, as a result of this dependence, a
late integrated Sachs-Wolfe effect appears. Here, an appropriate formalism is
used which allows us to improve on the analysis of the spatial scales and
locations of the main cosmological inhomogeneities producing this effect. The
study is performed in the framework of the currently preferred flat model with
cosmological constant, and it is also developed in an open model for
comparisons. Results from this analysis are used to discuss the contribution of
Great Attractor-like objects, voids, and other structures to the CMB
anisotropy.

</DOC>
<DOC>
<DOCNO> 12237 </DOCNO>
Aspects of topology of condensates and knotted solitons in condensed


  The knotted solitons introduced by Faddeev and Niemi is presently a subject
of great interest in particle and mathematical physics. In this paper we give a
condensed matter interpretation of the recent results of Faddeev and Niemi.

</DOC>
<DOC>
<DOCNO> 13880 </DOCNO>
The ferroelectric Mott-Hubbard phase of organic (TMTTF)2X conductors


  We present experimental evidences for a ferro-electric transition in the
family of quasi one- dimensional conductors (TMTTF)2X. We interpret this new
transition in the frame of the combined Mott-Hubbard state taking into account
the double action of the spontaneous charge disproportionation on the TMTTF
molecular stacks and of the X anionic potentials.

</DOC>
<DOC>
<DOCNO> 120898 </DOCNO>
Large-scale Cosmic Homogeneity from a Multifractal Analysis of the PSCz


  We investigate the behaviour of galaxy clustering on large scales using the
PSCz catalogue. In particular, we ask whether there is any evidence of
large-scale fractal behaviour in this catalogue. We find the correlation
dimension in this survey varies with scale, consistent with other analyses. For
example, our results on small and intermediate scales are consistent those
obtained from the QDOT sample, but the larger PSCz sample allows us to extend
the analysis out to much larger scales. We find firm evidence that the sample
becomes homogeneous at large scales; the correlation dimension of the sample is
D_2=2.992(3) for r>30 h^{-1} Mpc. This provides strong evidence in favour of a
Universe which obeys the Cosmological Principle.

</DOC>
<DOC>
<DOCNO> 119442 </DOCNO>
Cosmic ray acceleration at relativistic and ultrarelativistic shock


  Using the Monte Carlo simulations we apply a method of discrete small
amplitude particle momentum scattering to reproduce highly anisotropic
conditions at relativistic shocks. We discusse acceleration times scales in
relativistic shocks. Next, we describe newly found acceleration mechanism at
ultrarelativistic shocks. The universal spectral index and the acceleration
time for the shocks are given. In the end reflections from ultrarelativistic
shocks are considered.

</DOC>
<DOC>
<DOCNO> 71492 </DOCNO>
Brane World Sum Rules


  A set of consistency conditions is derived from Einstein equations for brane
world scenarios with a spatially periodic internal space. In particular, the
sum of the total tension of the flat branes and the non-negative integral of
the gradient energy of the bulk scalars must vanish. This constraint allows us
to make a simple consistency check of several models. We show that the
two-brane Randall-Sundrum model satisfies this constraint, but it does not
allow a generalization with smooth branes (domain walls), independently of the
issue of supersymmetry. The Goldberger-Wise model of brane stabilization has to
include the backreaction on the metric and the fine tuning of the cosmological
constant to satisfy the constraints. We check that this is achieved in the
DeWolfe-Freedman-Gubser-Karch scenario. Our constraints are automatically
satisfied in supersymmetric brane world models.

</DOC>
<DOC>
<DOCNO> 69634 </DOCNO>
Soft remnant interactions and rapidity gaps


  Soft colour exchange models give a unified description of both diffractive
and non-diffractive events, such that e-p and p-pbar collider data with and
without rapidity gaps are well reproduced. We show that these models also
describe the new Tevatron data on diffraction based on observed leading
antiprotons, which provide new information on how to treat the beam particle
remnant in the Monte Carlo model.

</DOC>
<DOC>
<DOCNO> 69454 </DOCNO>
The Semiclassical Approach to Small x Physics


  The semiclassical approach to small-x physics is briefly reviewed, where the
main emphasis is on the determination of the gluon distribution at NLO.

</DOC>
<DOC>
<DOCNO> 14031 </DOCNO>
Patterned Irradiation of YBa_2Cu_3O_(7-x) Thin Films


  We present a new experiment on YBa_2Cu_3O_{7-x} (YBCO) thin films using
spatially resolved heavy ion irradiation. Structures consisting of a periodic
array of strong and weak pinning channels were created with the help of metal
masks. The channels formed an angle of +/-45 Deg with respect to the symmetry
axis of the photolithographically patterned structures. Investigations of the
anisotropic transport properties of these structures were performed. We found
striking resemblance to guided vortex motion as it was observed in YBCO single
crystals containing an array of unidirected twin boundaries. The use of two
additional test bridges allowed to determine in parallel the resistivities of
the irradiated and unirradiated parts as well as the respective current-voltage
characteristics. These measurements provided the input parameters for a
numerical simulation of the potential distribution of the Hall patterning. In
contrast to the unidirected twin boundaries in our experiment both strong and
weak pinning regions are spatially extended. The interfaces between
unirradiated and irradiated regions therefore form a Bose-glass contact. The
experimentally observed magnetic field dependence of the transverse voltage
vanishes faster than expected from the numerical simulation and we interpret
this as a hydrodynamical interaction between a Bose-glass phase and a vortex
liquid.

</DOC>
<DOC>
<DOCNO> 100308 </DOCNO>
From Finite Sets to Feynman Diagrams


  `Categorification' is the process of replacing equations by isomorphisms. We
describe some of the ways a thoroughgoing emphasis on categorification can
simplify and unify mathematics. We begin with elementary arithmetic, where the
category of finite sets serves as a categorified version of the set of natural
numbers, with disjoint union and Cartesian product playing the role of addition
and multiplication. We sketch how categorifying the integers leads naturally to
the infinite loop space Omega^infinity S^infinity, and how categorifying the
positive rationals leads naturally to a notion of the `homotopy cardinality' of
a tame space. Then we show how categorifying formal power series leads to
Joyal's `especes des structures', or `structure types'. We also describe a
useful generalization of structure types called `stuff types'. There is an
inner product of stuff types that makes the category of stuff types into a
categorified version of the Hilbert space of the quantized harmonic oscillator.
We conclude by sketching how this idea gives a nice explanation of the
combinatorics of Feynman diagrams.

</DOC>
<DOC>
<DOCNO> 69402 </DOCNO>
Facts of life with gamma(5)


  The increasing precision of many experiments in elementary particle physics
leads to continuing interest in perturbative higher order calculations in the
electroweak Standard Model or extensions of it. Such calculations are of
increasing complexity because more loops and/or more legs are considered.
Correspondingly efficient computational methods are mandatory for many
calculations. One problem which affects the feasibility of higher order
calculations is the problem with gamma(5) in dimensional regularization. Since
the subject thirty years after its invention is still controversial I advocate
here some ideas which seem not to be common knowledge but might shed some new
light on the problem. I present arguments in favor of utilizing an
anticommuting gamma(5) and a simple 4-dimensional treatment of the hard
anomalies.

</DOC>
<DOC>
<DOCNO> 174438 </DOCNO>
Magnetic Trapping of Neutrons


  Accurate measurement of the lifetime of the neutron (which is unstable to
beta decay) is important for understanding the weak nuclear force and the
creation of matter during the Big Bang. Previous measurements of the neutron
lifetime have mainly been limited by certain systematic errors; however, these
could in principle be avoided by performing measurements on neutrons stored in
a magnetic trap. Neutral and charged particle traps are widely used tool for
studying both composite and elementary particles, because they allow long
interaction times and isolation from perturbing environments. Here we report
the magnetic trapping of neutrons. The trapping region is filled with
superfluid 4-He, which is used to load neutrons into the trap and as a
scintillator to detect their decay. Neutrons have a lifetime in the trap of 750
+330/-200 seconds, mainly limited by their beta decay rather than trap losses.
Our experiment verifies theoretical predictions regarding the loading process
and magnetic trapping of neutrons. Further refinement of this method should
lead to improved precision in the neutron lifetime measurement.

</DOC>
<DOC>
<DOCNO> 101646 </DOCNO>
A note on the Legendrian isotopy problem


  This paper has been withdrawn by the authors, due to a mistake pointed out by
Lenny Ng and Josh Sabloff.

</DOC>
<DOC>
<DOCNO> 100666 </DOCNO>
The lines of the Kontsevich integral and Rozansky's rationality


  This work develops some technology for accessing the loop expansion of the
Kontsevich integral of a knot. The setting is an application of the LMO
invariant to certain surgery presentations of knots by framed links in the
solid torus. A consequence of this technology is a certain recent conjecture of
Rozansky's. Rozansky conjectured that the Kontsevich integral could be
organised into a series of ``lines'' which could be represented by finite
$\Qset$-linear combinations of diagrams whose edges were labelled, in an
appropriate sense, with rational functions. Furthermore, the conjecture
requires that the denominator of the rational functions be at most the
Alexander polynomial of the knot. This conjecture is obtained from an
Aarhus-style surgery formula for this setting which we expect will have other
applications.

</DOC>
<DOC>
<DOCNO> 151951 </DOCNO>
The Topology of the AdS/CFT/Randall-Sundrum Complementarity


  The background geometries of the AdS/CFT and the Randall-Sundrum theories are
locally similar, and there is strong evidence for some kind of
"complementarity" between them; yet the global structures of the respective
manifolds are very different. We show that this apparent problem can be
understood in the context of a more complete global formulation of AdS/CFT. In
this picture, the brane-world arises within the AdS/CFT geometry as the
inevitable consequence of recent results on the global structure of manifolds
with "infinities". We argue that the usual coordinates give a misleading
picture of this global structure, much as Schwarzschild coordinates conceal the
global form of Kruskal-Szekeres space.

</DOC>
<DOC>
<DOCNO> 84136 </DOCNO>
Geometric treatment of the gravitomagnetic clock effect


  We have developed a general geometric treatment of the GCE valid for any
stationary axisymmetric metric. The method is based on the remark that the
world lines of objects rotating along spacely circular trajectories are in any
case, for those kind of metrics, helices drawn on the flat bidimensional
surface of a cylinder. Applying the obtained formulas to the special cases of
the Kerr and weak field metric for a spinning body, known results for time
delays and synchrony defects are recovered.

</DOC>
<DOC>
<DOCNO> 10523 </DOCNO>
Critical Behavior of the Three-Dimensional Ising Spin Glass


  We have simulated, using parallel tempering, the three dimensional Ising spin
glass model with binary couplings in a helicoidal geometry. The largest lattice
(L=20) has been studied using a dedicated computer (the SUE machine). We have
obtained, measuring the correlation length in the critical region, a strong
evidence for a second-order finite temperature phase transition ruling out
other possible scenarios like a Kosterlitz-Thouless phase transition. Precise
values for the $\nu$ and $\eta$ critical exponents are also presented.

</DOC>
<DOC>
<DOCNO> 118619 </DOCNO>
Sunyaev-Zel'dovich constraints from black hole-seeded proto-galaxies


  Recent studies of galactic nuclei suggest that most galaxies are seeded by
super-massive black holes which power the central nucleus. In this picture, the
proto-galactic object is likely to have undergone a very active phase during
which the surrounding medium was shocked and heated up to very high
temperatures. We predict the cosmological effects of this scenario in terms of
the thermal and kinetic Sunyaev-Zel'dovich distortions induced on galactic
scales by a population of proto-galaxies. These predictions are compared to the
observational limit on the mean Compton distortion set by the COBE-FIRAS
instrument. This enables us to derive tight constraints on the fraction of
proto-galaxies seeded by super-massive black holes as well as on the black
hole-to-spheroid mass ratio. Finally, we estimate the contribution of such a
population to the angular power spectrum of the Cosmic Microwave Background
temperature anisotropies on very small angular scales ($l\simeq 10^4-10^5$).

</DOC>
<DOC>
<DOCNO> 9829 </DOCNO>
Dynamical Properties of Spin-Orbital Chains in a Magnetic Field


  The excitation spectrum of the one-dimensional spin-orbital model in a
magnetic field is studied, using a recently developed dynamical density matrix
renormalization group technique. The method is employed on chains with up to 80
sites, and examined for test cases such as the spin-1/2 antiferromagnetic
Heisenberg chain, where the excitation spectrum is known exactly from the Bethe
Ansatz. In the spin-orbital chain, the characteristic dynamical response
depends strongly on the model parameters and the applied magnetic field. The
coupling between the spin and orbital degrees of freedom is found to influence
the incommensuration at finite magnetizations. In the regions of the phase
diagram with only massive spin and orbital excitations, a finite field is
required to overcome the spin gap. An incommensurate orbital mode is found to
become massless in this partially spin-polarized regime, indicating a strong
coupling between the two degrees of freedom. In the critical region with three
elementary gapless excitations, a prominent particle-hole excitation is
observed at higher energies, promoted by the biquadratic term in the model
Hamiltonian of the spin-orbital chain.

</DOC>
<DOC>
<DOCNO> 152124 </DOCNO>
Smooth Loops, Generalized Coherent States and Geometric Phases


  A description of generalized coherent states and geometric phases in the
light of the general theory of smooth loops is given.

</DOC>
<DOC>
<DOCNO> 12532 </DOCNO>
Phase diagram of the Mott Transition in a two-band Hubbard model in


  The Mott metal-insulator transition in the two-band Hubbard model in infinite
dimensions is studied by using the linearized dynamical mean-field theory
recently developed by Bulla and Potthoff. The phase boundary of the
metal-insulator transition is obtained analytically as a function of the
on-site Coulomb interaction at the $d$-orbital, the charge-transfer energy
between the $d$- and $p$-orbitals and the hopping integrals between $p-d$,
$d-d$ and $p-p$ orbitals. The result is in good agreement with the numerical
results obtained from the exact diagonalization method.

</DOC>
<DOC>
<DOCNO> 102042 </DOCNO>
Metriques autoduales sur la boule


  A conformal metric on a 4-ball induces on the boundary 3-sphere a conformal
metric and a trace-free second fundamental form. Conversely, such a data on the
3-sphere is the boundary of a unique selfdual conformal metric, defined in a
neighborhood of the sphere. In this paper we characterize the conformal metrics
and trace-free second fundamental forms on the 3-sphere (close to the standard
round metric) which are boundaries of selfdual conformal metrics on the whole
4-ball.
  When the data on the boundary is reduced to a conformal metric (the
trace-free part of the second fundamental form vanishes), one may hope to find
in the conformal class of the filling metric an Einstein metric, with a pole of
order 2 on the boundary. We determine which conformal metrics on the 3-sphere
are boundaries of such selfdual Einstein metrics on the 4-ball. In particular,
this implies the Positive Frequency Conjecture of LeBrun.
  The proof uses twistor theory, which enables to translate the problem in
terms of complex analysis; this leads us to prove a criterion for certain
integrable CR structures of signature (1,1) to be fillable by a complex domain.
  Finally, we solve an analogous, higher dimensional problem: selfdual Einstein
metrics are replaced by quaternionic-Kahler metrics, and conformal structures
on the boundary by quaternionic contact structures (previously introduced by
the author); in contrast with the 4-dimensional case, we prove that any small
deformation of the standard quaternionic contact structure on the (4m-1)-sphere
is the boundary of a quaternionic-Kahler metric on the 4m-ball.

</DOC>
<DOC>
<DOCNO> 101839 </DOCNO>
New Weighted Rogers-Ramanujan Partition Theorems and their Implications


  This paper has a two-fold purpose. First, by considering a reformulation of a
deep theorem of G\"ollnitz, we obtain a new weighted partition identity
involving the Rogers-Ramanujan partitions, namely, partitions into parts
differing by at least two. Consequences of this include Jacobi's celebrated
triple product identity for theta functions, Sylvester's famous refinement of
Euler's theorem, as well as certain weighted partition identities. Next, by
studying partitions with prescribed bounds on successive ranks and replacing
these with weighted Rogers-Ramanujan partitions, we obtain two new sets of
theorems - a set of three theorems involving partitions into parts $\not\equiv
0, \pm i$ ($mod$ 6), and a set of three theorems involving partitions into
parts $\not\equiv 0, \pm i$ ($mod$ 7), $i=1,2,3$.

</DOC>
<DOC>
<DOCNO> 39630 </DOCNO>
Physics Beyond the Standard Model


  I briefly summarize the prospects for extending our understanding of physics
beyond the standard model within the next five years.

</DOC>
<DOC>
<DOCNO> 118226 </DOCNO>
UBVRI photometric comparison sequences for symbiotic stars


  We present accurate UBVRI photometric comparison sequences around 20
symbiotic stars. The sequences extend over wide brightness and color ranges,
and are suited to cover quiescence as well as outburst phases. The sequences
are intended to assist both present time photometry as well as measurement of
photographic plates from historical archives. The types of variability
presented by symbiotic stars are reviewed. Individual notes on the known
photometric behaviour of the program stars are provided.

</DOC>
<DOC>
<DOCNO> 71035 </DOCNO>
Hadronic Three Jet Production at Next-to-Leading Order


  I present results of a next-to-leading order calculation of three jet
production at hadron colliders. This calculation will have many applications.
In addition to computing three-jet observables (spectra, mass distributions),
this calculation permits the first next-to-leading order studies (at hadron
colliders) of jet and event shape variables.

</DOC>
<DOC>
<DOCNO> 13730 </DOCNO>
Observation of a Linearly Dispersing Collective Mode in a Quantum Hall


  Double layer two-dimensional electron systems can exhibit a fascinating
collective phase believed to exhibit both quantum ferromagnetism and excitonic
superfluidity. This unusual phase has recently been found to exhibit tunneling
phenomena reminiscent of the Josephson effect. A key element of the theoretical
understanding of this bizarre quantum fluid is the existence of linearly
dispersing Goldstone collective modes. Using the method of tunneling
spectroscopy, we have demonstrated the existence of these modes. We find the
measured velocity to be in reasonable agreement with theoretical estimates.

</DOC>
<DOC>
<DOCNO> 9094 </DOCNO>
Effect of memory and dynamical chaos in long Josephson junctions


  A long Josephson junction in a constant external magnetic field and in the
presence of a dc bias current is investigated. It is shown that the system,
simulated by the sine-Gorgon equation, "remembers" a rapidly damping initial
perturbation and final asymptotic states are determined exactly with this
perturbation. Numerical solving of the boundary sine-Gordon problem and
calculations of Lyapunov indices show that this system has a memory even when
it is in a state of dynamical chaos, i.e., dynamical chaos does not destroy
initial information having a character of rapidly damping perturbation.

</DOC>
<DOC>
<DOCNO> 71891 </DOCNO>
The differential equation method: evaluation of complicated Feynman


  We discuss a progress in calculation of Feynman integrals which has been done
with help of the differential equation method and demonstrate the results for a
class of two-point two-loop diagrams.

</DOC>
<DOC>
<DOCNO> 178440 </DOCNO>
The Quasi-Molecular Stage of Ternary Fission


  We developed a three-center phenomenological model,able to explain
qualitatively the recently obtained experimental results concerning the
quasimolecular stage of a light-particle accompanied fission process. It was
derived from the liquid drop model under the assumption that the aligned
configuration, with the emitted particle between the light and heavy fragment,
is reached by increasing continuously the separation distance, while the radii
of the heavy fragment and of the light particle are kept constant. In such a
way,a new minimum of a short-lived molecular state appears in the deformation
energy at a separation distance very close to the touching point. This minimum
allows the existence of a short-lived quasi-molecular state, decaying into the
three final fragments.The influence of the shell effects is discussed. The
half-lives of some quasimolecular states which could be formed in the $^{10}$Be
and $^{12}$C accompanied fission of $^{252}$Cf are roughly estimated to be the
order of 1 ns, and 1 ms, respectively.

</DOC>
<DOC>
<DOCNO> 8931 </DOCNO>
Micro- and Macrosimulation of Freeway Traffic


  We present simulations of congested traffic in circular and open systems with
a non-local, gas-kinetic-based traffic model and a novel car-following model.
The model parameters are all intuitive and can be easily calibrated. Micro- and
macrosimulations with these models for identical vehicles on a single lane
produce the same traffic states, which also qualitatively agree with empirical
traffic observations. Moreover, the phase diagrams of traffic states in the
presence of bottlenecks for the microscopic car-following model and the
macroscopic gas-kinetic-based model almost agree. In both cases, we found
metastable regimes, spatially coexistent states, and a small region of
tristability. The distinction of different types of vehicles (cars and long
vehicles) yields additional insight and allows to reproduce empirical data even
more realistically, including the observed fluctuation properties of traffic
flows like the wide scattering of congested traffic data.
  Finally, as an alternative to the gas-kinetic approach, we propose a new
scheme for deriving non-local macroscopic traffic models from given microscopic
car-following models. Assuming identical (macroscopic) initial and boundary
conditions, we show that there are microscopic models for which the
corresponding macroscopic version displays an almost identical dynamics. This
enables us to combine micro- and macrosimulations of road sections by simple
algorithms, and even to simulate them simultaneously.

</DOC>
<DOC>
<DOCNO> 99419 </DOCNO>
The Weinstein conjecture in the uniruled manifolds


  In this note we prove the Weinstein conjecture for a class of symplectic
manifolds including the uniruled manifolds based on Liu-Tian's result.

</DOC>
<DOC>
<DOCNO> 119046 </DOCNO>
Delayed Recombination


  Under the standard model for recombination of the primeval plasma, and the
cold dark matter model for structure formation, recent measurements of the
first peak in the angular power spectrum of the cosmic microwave background
temperature indicate the spatial geometry of the universe is nearly flat. If
sources of Lya resonance radiation, such as stars or active galactic nuclei,
were present at z ~ 1000 they would delay recombination, shifting the first
peak to larger angular scales, and producing a positive bias in this measure of
space curvature. It can be distinguished from space curvature by its
suppression of the secondary peaks in the spectrum.

</DOC>
<DOC>
<DOCNO> 101155 </DOCNO>
Dependence on the spin structure of the Dirac spectrum


  The theme is the influence of the spin structure on the Dirac spectrum of a
spin manifold. We survey examples and results related to this question.

</DOC>
<DOC>
<DOCNO> 121477 </DOCNO>
On the variation of the Initial Mass Function


  (shortened) In this contribution an average or Galactic-field IMF is defined,
stressing that there is evidence for a change in the power-law index at only
two masses: near 0.5 Msun and 0.08 Msun. Using this supposed universal IMF, the
uncertainty inherent to any observational estimate of the IMF is investigated,
by studying the scatter introduced by Poisson noise and the dynamical evolution
of star clusters. It is found that this apparent scatter reproduces quite well
the observed scatter in power-law index determinations, thus defining the
fundamental limit within which any true variation becomes undetectable.
Determinations of the power-law indices alpha are subject to systematic errors
arising mostly from unresolved binaries. The systematic bias is quantified
here, with the result that the single-star IMFs for young star-clusters are
systematically steeper by d_alpha=0.5 between 0.1 and 1 Msun than the
Galactic-field IMF, which is populated by, on average, about 5 Gyr old stars.
The MFs in globular clusters appear to be, on average, systematically flatter
than the Galactic-field IMF, and the recent detection of ancient white-dwarf
candidates in the Galactic halo and absence of associated low-mass stars
suggests a radically different IMF for this ancient population. Star-formation
in higher-metallicity environments thus appears to produce relatively more
low-mass stars.

</DOC>
<DOC>
<DOCNO> 100584 </DOCNO>
Gerbes of chiral differential operators. III


  This note is a sequel to "Gerbes of chiral differential operators. II",
math.AG/0003170. We study gerbes of chiral differential operators acting on the
exterior algebra $\Lambda E$ of a vector bundle over a smooth algebraic variety
$X$. When $E=\Omega^1_X$ this gerbe admits a canonical global section which
coincides with the chiral de Rham complex of $X$.

</DOC>
<DOC>
<DOCNO> 178544 </DOCNO>
Single particle spectrum and binding energy of nuclear matter


  In non-relativistic Brueckner calculations of nuclear matter, the
self-consistent single particle potential is strongly momentum dependent. To
simplify the calculations, a parabolic approximation is often used in the
literature. The variation in the binding energy value introduced by the
parabolic approximation is quantitatively analyzed in detail. It is found that
the approximation can introduce an uncertainty of 1-2 MeV near the saturation
density.

</DOC>
<DOC>
<DOCNO> 178520 </DOCNO>
The role of $\nu$-induced reactions on lead and iron in neutrino


  We have calculated cross sections and branching ratios for neutrino induced
reactions on ^{208}Pb and ^{56}Fe for various supernova and
accelerator-relevant neutrino spectra. This was motivated by the facts that
lead and iron will be used on one hand as target materials in future neutrino
detectors, on the other hand have been and are still used as shielding
materials in accelerator-based experiments. In particular we study the
inclusive ^{56}$Fe(\nu_e,e^-)$^{56}Co and ^{208}$Pb(\nu_e,e^-)$^{208}Bi cross
sections and calculate the neutron energy spectra following the decay of the
daughter nuclei. These reactions give a potential background signal in the
KARMEN and LSND experiment and are discussed as a detection scheme for
supernova neutrinos in the proposed OMNIS and LAND detectors. We also study the
neutron-emission following the neutrino-induced neutral-current excitation of
^{56}Fe and ^{208}Pb.

</DOC>
<DOC>
<DOCNO> 119564 </DOCNO>
First correlation between compact object and circumstellar disk in the


  A remarkable correlation between the H-alpha emission line and the radio
behaviour of LSI+61 303 (V615 Cas, GT 0236+610) over its 4 yr modulation is
discovered. The radio outburst peak is shifted by a quarter of the 4 yr
modulation period (about 400 days) with respect to the equivalent width of the
H-alpha emission line variability. The onset of the LSI+61 303 radio outbursts
varies in phase with the changes of the H-alpha emission line, at least during
the increase of H-alpha equivalent width. This is the first clear correlation
between the emission associated to the compact object and the Be circumstellar
disk in a Be/X-ray binary system.

</DOC>
<DOC>
<DOCNO> 9092 </DOCNO>
Role of Bond-Bond Interaction in the Extended Hubbard Chain


  Phase diagrams of the one-dimensional extended Hubbard model with a nearest
neighbor interaction $V$ and site-off-diagonal (bond-charge $X$ and bond-bond
$W$) interactions at half-filling are obtained numerically, using the
level-crossing approach for finite-size clusters. This analysis is
straightforward extension of the preceding work [cond-mat/9909277], where only
the $X$ term is considered as a site-off-diagonal term. Similarly to the $X$
term, the $W$ term enlarges bond-charge-density-wave (BCDW) and
bond-spin-density-wave
 (BSDW) phases for $W<0$ and $W>0$ cases, respectively. In the strong-coupling
region, however, the $W$ term causes ferromagnetism for
 $W>0$, and shifts the boundary of the phase separation in the
 $U/t\ll-1$ region, which are different from the roles of the $X$ term.
 In addition, we discuss a parameter region where the BSDW state is the exact
ground state, and show that the exactly solvable point appears just on the
phase boundary between the BSDW and the ferromagnetic phases.

</DOC>
<DOC>
<DOCNO> 8434 </DOCNO>
Strongly Correlated Cerium Systems: Non-Kondo Mechanism for Moment


  We present an ab initio based method which gives clear insight into the
interplay between the hybridization, the coulomb exchange, and the
crystal-field interactions, as the degree of 4f localization is varied across a
series of strongly correlated cerium systems. The results for the ordered
magnetic moments, magnetic structure, and ordering temperatures are in
excellent agreement with experiment, including the occurence of a moment
collapse of non-Kondo origin. In contrast, standard ab initio density
functional calculations fail to predict, even qualitatively, the trend of the
unusual magentic properties.

</DOC>
<DOC>
<DOCNO> 123202 </DOCNO>
Molecular Carbon Chains and Rings in TMC-1


  We present mapping results in several rotational transitions of HC3N, C6H,
both cyclic and linear C3H2 and C3H, towards the cyanopolyyne peak of the
filamentary dense cloud TMC-1 using the IRAM 30m and MPIfR 100m telescopes. The
spatial distribution of the cumulene carbon chain propadienylidene H2C3
(hereafter l-C3H2) is found to deviate significantly from the distributions of
the cyclic isomer c-C3H2, HC3N, and C6H which in turn look very similar. The
cyclic over linear abundance ratio of C3H2 increases by a factor of 3 across
the filament, with a value of 28 at the cyanopolyyne peak. This abundance ratio
is an order of magnitude larger than the range (3 to 5) we observed in the
diffuse interstellar medium. The cyclic over linear abundance ratio of C3H also
varies by ~2.5 in TMC-1, reaching a maximum value (13) close to the
cyanopolyyne peak. These behaviors might be related to competitive processes
between ion-neutral and neutral-neutral reactions for cyclic and linear
species.

</DOC>
<DOC>
<DOCNO> 71848 </DOCNO>
Infrared Fixed Point Structure in Minimal Supersymmetric Standard Model


  We study in detail the renomalization group evolution of Yukawa couplings and
soft supersymmetry breaking trilinear couplings in the minimal supersymmetric
standard model with baryon and lepton number violation. We obtain the exact
solutions of these equations in a closed form, and then depict the infrared
fixed point structure of the third generation Yukawa couplings and the highest
generation baryon and lepton number violating couplings. Approximate analytical
solutions for these Yukawa couplings and baryon and lepton number violating
couplings, and the soft supersymmetry breaking couplings are obtained in terms
of their initial values at the unification scale. We then numerically study the
infrared fixed surfaces of the model, and illustrate the approach to the fixed
points.

</DOC>
<DOC>
<DOCNO> 71048 </DOCNO>
Aspects of Chiral Symmetry


  We give a pedagogical review of implications of chiral symmetry in QCD.
First, we briefly discuss classical textbook subjects such as the axial
anomaly, spontaneous breaking of the flavor-nonsinglet chiral symmetry,
formation of light pseudo-Goldstone particles, and their effective
interactions. Then we proceed to other issues. We explain in some detail a
recent discovery how to circumvent the Nielsen--Ninomiya's theorem and
implement chirally symmetric fermions on the lattice. We touch upon such
classical issues as the Vafa-Witten's theorem and 't Hooft's anomaly matching
conditions. We derive a set of exact theorems concerning the dynamics of the
theory in a finite Euclidean volume and the behavior of the Dirac spectral
density. Finally, we discuss an imaginary world with a nonzero value of the
vacuum angle theta.

</DOC>
<DOC>
<DOCNO> 71651 </DOCNO>
Electroweak Radiative Corrections to W and Z Boson Production at Hadron


  For the envisioned high precision measurement of the W boson mass at the
Tevatron and LHC it is crucial that the theoretical predictions for the W and Z
production processes are under control. We briefly summarize the status of the
electroweak radiative corrections to p p(pbar) -> W -> l nu and p p(pbar) ->
Z,gamma -> l+ l- (l=e,mu), and present some numerical results.

</DOC>
<DOC>
<DOCNO> 11649 </DOCNO>
Quantum skyrmions and the destruction of long-range antiferromagnetic


  We study the destruction of the antiferromagnetic order in the high-Tc
superconductors La(2-x)Sr(x)CuO(4) and YBa(2)Cu(3)O(6+x) in the framework of
the CP1-nonlinear sigma model formulation of the 2D quantum Heisenberg
antiferromagnet. The dopants are introduced as independent fermions with
appropriate dispersion relations determined by the shape of the Fermi surface.
The energy of skyrmion topological defects, which are shown to be introduced by
doping, is used as an order parameter for antiferromagnetic order. We obtain
analytic expressions for this as a function of doping which allow us to plot
the curves T_N(x_c)\times x_c and M(x)\times x, for both YBCO and LSCO, in good
quantitative agreement with the experimental data.

</DOC>
<DOC>
<DOCNO> 119968 </DOCNO>
Cosmic Ray Generation by Quasar Remnants: Constraints and Implications


  The quasar remnant cores of nearby giant elliptical galaxies NGC 4486 (M87),
NGC 1399, NGC 4649 and NGC 4472 are the sites of supermassive (greater than one
billion solar masses) black holes. These objects are investigated as to the
viability of the conjecture that they could harbor compact dynamos capable of
generating the highest energy cosmic rays. For an accretion process involving
an equipartition magnetic field near the event horizons of the underlying
putative spun-up black holes, the energy achievable in accelerating protons
could well be greater or equal than 100 EeV for all these when only considering
the drag induced by curvature radiation. Estimates of the SED (spectral energy
distribution) of ambient core photons lead to the conclusion that the energy
losses arising from photo-pion production in proton collisions with these
target photons are relatively small for all but M87. For M87, the ambient
photon field is likely to be a limiting factor. Accretion rates on the order of
one solar mass per year, comparable to the Bondi rates and to the stellar mass
loss rates, are associated with (greater than 100 EeV) cosmic ray generation in
the other (electromagnetically dark) galactic core sites. If these sites are
found to be sources of such cosmic rays, it would suggest the presence of a
global inflow of interstellar gas all the way into the center of the host
galaxy.

</DOC>
<DOC>
<DOCNO> 119742 </DOCNO>
The role of nonthermal electrons in the optical continuum of stellar


  We explore the possibility that the continuum emission in stellar flares is
powered by nonthermal electrons accelerated during the flares. We compute the
continuum spectra from an atmospheric model for a dMe star, AD Leo, at its
quiescent state, when considering the nonthermal excitation and ionisation
effects by precipitating electron beams. The results show that if the electron
beam has an energy flux large enough, the U band brightening and, in
particular, the U-B colour are roughly comparable with observed values for a
typical large flare. Moreover, for electron beams with a moderate energy flux,
a decrease of the emission at the Paschen continuum appears. This can explain
at least partly the continuum dimming observed in some stellar flares. Adopting
an atmospheric model for the flaring state can further raise the continuum flux
but it yields a spectral colour incomparable with observations. This implies
that the nonthermal effects may play the chief role in powering the continuum
emission in some stellar flares.

</DOC>
<DOC>
<DOCNO> 116377 </DOCNO>
Asynchronous accelerator with RFQ injection for active longitudinal


  An asynchronous accelerator is described, in which the principle of its
operation permits the active longitudinal bunch compression of accelerated
proton beams, to overcome the space charge limitation effects of intense
bunches. It is shown that accelerated bunches from an RFQ linac can be adapted
for Asynchronac injection for a multiple of choices in the acceleration
frequencies of the RFQ and the Asynchronac. The offered new type of accelerator
system is especially suitable to accelerate proton beams for up to 100MeV
energy and hundreds of mA average current.

</DOC>
<DOC>
<DOCNO> 100950 </DOCNO>
Short geodesics and end invariants


  This expository article discusses some connections between the geometry of a
hyperbolic 3-manifold homotopy-equivalent to a surface, and the combinatorial
properties of its end invariants. In particular a necessary and sufficient
condition is stated for the manifold to have arbitrarily short geodesics, in
terms of a sequence of coefficients called subsurface projection distances,
which are analogous in some ways to continued-fraction coefficients. (The proof
of sufficiency appeared in math.GT/9907070)

</DOC>
<DOC>
<DOCNO> 83056 </DOCNO>
Multiplicative Algorithm for Orthgonal Groups and Independent Component


  The multiplicative Newton-like method developed by the author et al. is
extended to the situation where the dynamics is restricted to the orthogonal
group. A general framework is constructed without specifying the cost function.
Though the restriction to the orthogonal groups makes the problem somewhat
complicated, an explicit expression for the amount of individual jumps is
obtained. This algorithm is exactly second-order-convergent. The global
instability inherent in the Newton method is remedied by a
Levenberg-Marquardt-type variation. The method thus constructed can readily be
applied to the independent component analysis. Its remarkable performance is
illustrated by a numerical simulation.

</DOC>
<DOC>
<DOCNO> 9600 </DOCNO>
Vortex lattices in a stirred Bose-Einstein condensate


  We stir with a focused laser beam a Bose-Einstein condensate of $^{87}$Rb
atoms confined in a magnetic trap. We observe the formation of a single vortex
for a stirring frequency exceeding a critical value. At larger rotation
frequencies we produce states of the condensate for which up to eleven vortices
are simultaneously present. We present measurements of the decay of a vortex
array once the stirring laser beam is removed.

</DOC>
<DOC>
<DOCNO> 10631 </DOCNO>
Spin Excitation in d-wave Superconductors : A Fermi Liquid Picture


  A detailed study of the Inelastic Neutron Scattering (INS) spectra of the
high-$T_c$ cuprates based on the Fermi liquid (FL) picture is given. We focus
on the issue of the transformation between the commensurate and incommensurate
(IC) excitation driven by frequency or $temperature$. For
La$_{2-x}$Sr$_x$CuO$_4$ (LSCO), the condition of small $\Delta(0)/v_F a$ (where
$a$ is the lattice constant, and henceforth will be set to 1) can
simultaneously reproduces the always existing IC peaks in the superconducting
(SC) and normal state, and the always fixed location at temperature or
frequency change. For YBa$_2$Cu$_3$O$_{6+x}$ (YBCO), a moderate $\Delta(0)/v_F
a$ and proximity of the van Hove singularity (vHS) at ${\bar M}=(0,\pi)$ to the
Fermi level can reproduce the frequency- and temperature-driven shifting IC
peaks in the SC state, and the vanishing of the IC peak in the normal state.
The commensurate peak is found to be more appropriately described as a random
phase approximation (RPA) effect. We address the conditional peak shifting
behavior to a refined consideration on the nesting effect which is previously
overlook. As a result, both the data on LSCO and the recent data on YBCO (on
YBa$_2$Cu$_3$O$_{6.7}$ by Arai $et$ $al.$ and YBa$_2$Cu$_3$O$_{6.85}$ by
Bourges $et$ $al.$) can be reasonably reconciled within a FL picture. We also
point out that the one-dimensional-like data by Mook $et$ $al.$ on a detwinned
and more underdoped sample YBa$_2$Cu$_3$O$_{6.6}$ could be due to a gap
anisotropy effect discussed by Rendell and Carbotte, and we proceed to suggest
a way of clarifying it.

</DOC>
<DOC>
<DOCNO> 118381 </DOCNO>
Lithium and rotation on the subgiant branch II. Theoretical analysis of


  Lithium abundances and rotation, determined for 120 subgiant stars in Lebre
et al. (1999) are analyzed. To this purpose, the evolutionary status of the
sample as well as the individual masses have been determined using the
HIPPARCOS trigonometric parallax measurements to locate very precisely our
sample stars in the HR diagram. We look at the distributions of A(Li) and Vsini
with mass when stars evolve from the main sequence to the subgiant branch. For
most of the stars in our sample we find good agreement with the dilution
predictions. However, the more massive cool stars with upper limits of Li
abundances show a significant discrepancy with the theoretical predictions,
even if the Non-LTE effects are taken into account. For the rotation behaviour,
our analysis confirms that low mass stars leave the main sequence with a low
rotational rate, while more massive stars are slowed down only when reaching
the subgiant branch. We also checked the connection between the observed
rotation behaviour and the magnetic braking due to the deepening of the
convective envelope. Our results shed new light on the lithium and rotation
discontinuities in the evolved phase.

</DOC>
<DOC>
<DOCNO> 116796 </DOCNO>
Re-examination of the "3/4-law" of Metabolism


  We examine the scaling law $B \propto M^{\alpha}$ which connects organismal
metabolic rate $B$ with organismal mass $M$, where $\alpha$ is commonly held to
be 3/4. Since simple dimensional analysis suggests $\alpha=2/3$, we consider
this to be a null hypothesis testable by empirical studies. We re-analyze data
sets for mammals and birds compiled by Heusner, Bennett and Harvey, Bartels,
Hemmingsen, Brody, and Kleiber, and find little evidence for rejecting
$\alpha=2/3$ in favor of $\alpha=3/4$. For mammals, we find a possible
breakdown in scaling for larger masses reflected in a systematic increase in
$\alpha$. We also review theoretical justifications of $\alpha=3/4$ based on
dimensional analysis, nutrient-supply networks, and four-dimensional biology.
We find that present theories for $\alpha=3/4$ require assumptions that render
them unconvincing for rejecting the null hypothesis that $\alpha=2/3$.

</DOC>
<DOC>
<DOCNO> 8905 </DOCNO>
Nodal Quasiparticle Lifetime in the Superconducting State of BSCCO(2212)


  We have measured the complex conductivity of a BSCCO(2212) thin film between
0.2 and 1.0 THz. We find the conductivity in the superconducting state to be
well described as the sum of contributions from quasiparticles, the condensate,
and order parameter fluctuations which draw 30% of the spectral weight from the
condensate. An analysis based on this decomposition yields a quasiparticle
scattering rate on the order of k_(B)*T/(hbar) for temperatures below Tc.

</DOC>
<DOC>
<DOCNO> 85297 </DOCNO>
The Effect of Sources on the Inner Horizon of Black Holes


  Single pulse of null dust and colliding null dusts both transform a regular
horizon into a space-like singularity in the space of colliding waves. The
local isometry between such space-times and black holes extrapolates these
results to the realm of black holes. However, inclusion of particular scalar
fields instead of null dusts creates null singularities rather than space-like
ones on the inner horizons of black holes.

</DOC>
<DOC>
<DOCNO> 101410 </DOCNO>
Analysis of geometric operators on open manifolds: A groupoid approach


  We use algebras of pseudodifferential operators on groupoids to study
geometric operators on non-compact manifolds and singular spaces. The first
step is to establish that the geometric operators are in our algebras. This
then leads to criteria for Fredholmness for geometric operators on suitable
non-compact manifolds, as well as to an inductive procedure to study their
essential spectrum. As an application, we answer a question of Melrose on the
essential spectrum of the Laplace operator on manifolds with multi-cylindrical
ends.

</DOC>
<DOC>
<DOCNO> 118600 </DOCNO>
Blue compact galaxies and the primordial 4Helium abundance


  Blue compact galaxies (BCG) are ideal objects in which to derive the
primordial 4He abundance because they are chemically young and have not had a
significant stellar He contribution. We discuss a self-consistent method which
makes use of all the brightest He I emission lines in the optical range and
solves consistently for the electron density of the He II zone. We pay
particular attention to electron collision and radiative transfer as well as
underlying stellar absorption effects which may make the He I emission lines
deviate from their recombination values. Using a large homogeneous sample of 45
low-metallicity H II regions in BCGs, and extrapolating the Y-O/H and Y-N/H
linear regressions to O/H = N/H = 0, we obtain Yp = 0.2443+/-0.0015, in
excellent agreement with the weighted mean value Yp = 0.2452+/-0.0015 obtained
from the detailed analysis of the two most metal-deficient BCGs known, I Zw 18
and SBS 0335-052. The derived slope dY/dZ = 2.4+/-1.0 is in agreement with the
value derived for the Milky Way and with simple chemical evolution models with
homogeneous outflows. Adopting Yp = 0.2452+/-0.0015 leads to a baryon-to-photon
ratio of (4.7+/-1.0)x10^{-10} and to a baryon mass fraction in the Universe
Omega_b h^2_{50} = 0.068+/-0.015, consistent with the value derived from the
primordial D abundance of Burles & Tytler (1998).

</DOC>
<DOC>
<DOCNO> 69455 </DOCNO>
Reaction Operator Approach to Non-Abelian Energy Loss


  A systematic expansion of the induced inclusive gluon radiation associated
with jet production in a dense QCD plasma is derived using a reaction operator
formalism. Analytic expressions for the transverse momentum and light-cone
momentum distributions are derived to all orders in powers of the gluon opacity
of the medium, $N\sigma_g/A=L/\lambda_g$. The reaction operator approach also
leads to a simple algebraic proof of the ``color triviality'' of single
inclusive distributions and to a solvable set of recursion relations. The
analytic solution generalizes previous continuum solutions (BDMPS) for
applications to mesoscopic QCD plasmas. The solution is furthermore not
restricted to uncorrelated geometries and allows for evolving screening scales
as well as the inclusion of finite kinematic constraints. The later is
particularly important because below LHC energies the kinematic constraints
significantly decrease the non-abelian energy loss. Our solution for the
inclusive distribution also generalizes the finite order exclusive (tagged)
distribution case studied previously (GLV1). The form of the analytic solution
is well suited for numerical implementation in Monte Carlo event generators to
enable more accurate calculations of jet quenching in ultra-relativistic
nuclear collisions. Numerical results illustrating the constributions of the
first three orders in opacity are compared to the ``self-quenching'' hard
radiation intensity. A surprising result is that the induced gluon radiation
intensity is dominated by the (quadratic in $L$) first order opacity
contribution for realistic geometries and jet energies in nuclear collisions.

</DOC>
<DOC>
<DOCNO> 68521 </DOCNO>
Perspectives on Finding the Neutrino Nature


  The possibility of determining the neutrino nature is considered in view of
the most recent experimental observations. The analysis combines schemes with
three and four neutrinos.The data on oscillations is put together with that
from the search of neutrinoless double beta decay and results on tritium beta
decay. All solar neutrino oscillation solutions are taken into account. The
sensitivity of the problem on future experimental bounds from GENIUS is
studied. Dirac neutrinos are shown to be unavoidable already at present in some
schemes and the constraints will quickly become more stringent with future
data. The consequences of including bounds from Cosmology on the neutrino
content of Hot Dark Matter are commented.

</DOC>
<DOC>
<DOCNO> 151581 </DOCNO>
New vacua for Yang-Mills theory on a 3-torus


  In this thesis we discuss recent new insights in the structure of the moduli
space of flat connections of Yang-Mills theory on a 3-torus. Chapter 2
discusses the computation of Witten's index for 4-dimensional gauge theories,
and the paradox that arises in comparing various computations. This was
resolved by the discovery that for orthogonal and exceptional gauge groups,
periodic flat connections exist that are contained in seperate, disconnected
components of the moduli space. Chapter 3 and 4 discuss some aspects of the
construction of holonomies parametrising vacua on such disconnected components.
Chapter 5 demonstrates a construction of vacua and holonomies for gauge
theories with classical groups, with non-periodic (twisted) boundary
conditions, using an orientifold description. The new solutions with
exceptional and orthogonal gauge groups also occur in string theory. Chapter 6,
containing previously unpublished material, shows that they can be realised
within heterotic string theories as asymmetric orbifolds. The presence of
string winding states modifies the analysis for the gauge theory in a crucial
way, eliminating many possibilities. The remaining ones are related by string
dualities to known and new theories.

</DOC>
<DOC>
<DOCNO> 119740 </DOCNO>
Einstein Cluster Alignments Revisited


  We have examined whether the major axes of rich galaxy clusters tend to point
toward their nearest neighboring cluster. We have used the data of Ulmer,
McMillan, and Kowalski, who used position angles based on X-ray morphology. We
also studied a subset of this sample with updated positions and distances from
the MX Northern Abell Cluster Survey (for rich clusters ($R \geq 1$) with well
known redshifts). A Kolmogorov-Smirnov (KS) test showed no significant signal
for nonrandom angles on any scale $\leq 100h^{-1}$Mpc. However, refining the
null hypothesis with the Wilcoxon rank-sum test, we found a high confidence
signal for alignment. Confidence levels increase to a high of 99.997% as only
near neighbors which are very close are considered. We conclude there is a
strong alignment signal in the data, consistent with gravitational instability
acting on Gaussian perturbations.

</DOC>
<DOC>
<DOCNO> 121775 </DOCNO>
Dynamical Instabilities in Extrasolar Planetary Systems Containing Two


  Instabilities and strong dynamical interactions between several giant planets
have been proposed as a possible explanation for the surprising orbital
properties of extrasolar planetary systems. In particular, dynamical
instabilities would seem to provide a natural mechanism for producing the
highly eccentric orbits seen in many systems. Here we present results from
numerical integrations for the dynamical evolution of planetary systems
containing two identical giant planets in nearly circular orbits very close to
the dynamical stability limit. We determine the statistical properties of the
three main types of systems resulting from the development of an instability:
systems containing one planet, following either a collision between the two
initial planets, or the ejection of one of them to infinity, and systems
containing two planets in a new, quasi-stable configuration. We discuss the
implications of our results for the formation and evolution of observed
extrasolar planetary systems. We conclude that the distributions of
eccentricities and semimajor axes for observed systems cannot be explained
easily by invoking dynamical interactions between two planets initially on
circular orbits. While highly eccentric orbits can be produced naturally by
these interactions, collisions between the two planets, which occur frequently
in the range of observed semimajor axes, would result in many more nearly
circular orbits than in the observed sample.

</DOC>
<DOC>
<DOCNO> 10690 </DOCNO>
Nucleation of bended vortices in Bose-Einstein condensates in elongated


  We study the generation of vortices in rotating axially elongated
magneto-optical traps, a situation which has been realized in a recent
experiment (K. W. Madison, F. Chevy, W. Wohlleben, J. Dalibard, Phys. Rev.
Lett. 84, 806 (2000)). We predict that at a critical frequency the condensate
experiences a symmetry breaking and changes from a convex cloud to a state with
one bended vortex. We also discuss several effects which enlarge the critical
frequency with respect to other geometries of the trap: these are, (i) the
failure of the Thomas-Fermi approximation on the transverse degrees of freedom
of the condensate, (ii) the enhancement of the transverse asymmetry of the trap
by means of rotation and (iii) the yet unobserved bending of the vortex lines.

</DOC>
<DOC>
<DOCNO> 39792 </DOCNO>
Prospects of Measuring General Higgs Couplings at e^+e^- Linear


  We examine how accurately the general HZV couplings, with V=Z,gamma, may be
determined by studying e^+e^- --> Hff-bar processes at future e^+e^- linear
colliders. By using the optimal-observable method, which makes use of all
available experimental information, we find out which combinations of the
various HZV coupling terms may be constrained most efficiently with high
luminosity. We also assess the benefits of measuring the tau-lepton helicities,
identifying the bottom-hadron charges, polarizing the electron beam and running
at two different collider energies. The HZZ couplings are generally found to be
well constrained, even without these options, while the HZ-gamma couplings are
not. The constraints on the latter may be significantly improved by beam
polarization.

</DOC>
<DOC>
<DOCNO> 151057 </DOCNO>
A Note on Supergravity Duals of Noncommutative Yang-Mills Theory


  A class of supergravity backgrounds have been proposed as dual descriptions
of strong coupling large-N noncommutative Yang-Mills (NCYM) theories in 3+1
dimensions. However calculations of correlation functions in supergravity from
an evaluation of relevant classical actions appear ambiguous. We propose a
resolution of this ambiguity. Assuming that {\it some} holographic description
exists - regardless of whether it is the NCYM theory - we argue that there
should be operators in the holographic boundary theory which create normalized
states of definite energy and momenta. An operator version of the dual
correspondence then provides a calculation of correlators of these operators in
terms of bulk Green's functions. We show that in the low energy limit the
correlators reproduce expected answers of the ordinary Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 80670 </DOCNO>
Matrix Distributed Processing: A set of C++ Tools for implementing


  We present a set of programming tools (classes and functions written in C++
and based on Message Passing Interface) for fast development of generic
parallel (and non-parallel) lattice simulations. They are collectively called
MDP 1.2.
  These programming tools include classes and algorithms for matrices, random
number generators, distributed lattices (with arbitrary topology), fields and
parallel iterations. No previous knowledge of MPI is required in order to use
them.
  Some applications in electromagnetism, electronics, condensed matter and
lattice QCD are presented.

</DOC>
<DOC>
<DOCNO> 7869 </DOCNO>
Response of non-equilibrium systems at criticality: Ferromagnetic models


  We study the dynamics of ferromagnetic spin systems quenched from infinite
temperature to their critical point. We show that these systems are aging in
the long-time regime, i.e., their two-time autocorrelation and response
functions and associated fluctuation-dissipation ratio are non-trivial scaling
functions of both time variables. This is exemplified by the exact analysis of
the spherical model in any dimension D>2, and by numerical simulations on the
two-dimensional Ising model. We show in particular that, for $1\ll s$ (waiting
time) $\ll t$ (observation time), the fluctuation-dissipation ratio possesses a
non-trivial limit value $X_\infty$, which appears as a dimensionless amplitude
ratio, and is therefore a novel universal characteristic of non-equilibrium
critical dynamics. For the spherical model, we obtain $X_\infty=1-2/D$ for
2<D<4, and $X_\infty=1/2$ for D>4 (mean-field regime). For the two-dimensional
Ising model we measure $X_\infty\approx0.26\pm0.01$.

</DOC>
<DOC>
<DOCNO> 102287 </DOCNO>
Transformations on the set of all n-dimensional subspaces of a Hilbert


  Wigner's classical theorem on symmetry transformations plays a fundamental
role in quantum mechanics. It can be formulated, for example, in the following
way: Every bijective transformation on the set L of all 1-dimensional subspaces
of a Hilbert space H which preserves the angle between the elements of L is
induced by either a unitary or an antiunitary operator on H. The aim of this
paper is to extend Wigner's result from the 1-dimensional case to the case of
n-dimensional subspaces of H with n fixed.

</DOC>
<DOC>
<DOCNO> 121600 </DOCNO>
Scales of the Extra Dimensions and their Gravitational Wave Backgrounds


  Circumstances are described in which symmetry breaking during the formation
of our three-dimensional brane within a higher-dimensional space in the early
universe excites mesoscopic classical radion or brane-displacement degrees of
freedom and produces a detectable stochastic background of gravitational
radiation. The spectrum of the background is related to the unification energy
scale and the the sizes and numbers of large extra dimensions. It is shown that
properties of the background observable by gravitational-wave observatories at
frequencies $f\approx 10^{-4}$ Hz to $10^3$ Hz contain information about
unification on energy scales from 1 to $10^{10}$ TeV, gravity propagating
through extra-dimension sizes from 1 mm to $10^{-18}$mm, and the dynamical
history and stabilization of from one to seven extra dimensions.

</DOC>
<DOC>
<DOCNO> 68263 </DOCNO>
Phenomenology of the radion in Randall-Sundrum scenario at colliders


  Phenomenology of a radion ($\phi$) that stabilizes the modulus in the
Randall-Sundrum scenario is considered. The radion couples to the trace of
energy momentum tensor of the standard model (SM) with a strength suppressed
only by a new scale ($\Lambda_{\phi}$) of an order of the electroweak scale. In
particular, the effective coupling of a radion to two gluons are enhanced due
to the trace anomaly of QCD. Therefore, its production cross section at hadron
colliders could be enhanced, and the dominant decay mode of a relatively light
radion is $\phi$ -> g g, unlike the SM Higgs boson case. We also present
constraints on the mass $m_{\phi}$ and the new scale $\Lambda_{\phi}$ from the
Higgs search limit at LEP and perturbative unitarity bound.

</DOC>
<DOC>
<DOCNO> 122033 </DOCNO>
IRAM observations of JVAS/CLASS gravitational lenses


  We have searched for molecular absorption lines at millimeter wavelengths in
eleven gravitational lens systems discovered in the JVAS/CLASS surveys of flat
spectrum radio sources. Spectra of only one source 1030+074 were obtained in
the 3-, 2- and 1.3-millimeter band at the frequencies corresponding to common
molecular transitions of CO and HCO+ as continuum emission was not found in any
of the other sources. We calculated upper limits to the column density in
molecular absorption for 1030+074, using an excitation temperature of 15 K, to
be N_{CO} < 6.3 x 10^{13} cm^{-2} and N_{HCO+} < 1.3 x 10^{11} cm^{-2},
equivalent to hydrogen column density of the order N_H < 10^{18} cm^{-2},
assuming standard molecular abundances. We also present the best upper limits
of the continuum at the lower frequency for the other 10 gravitational lenses.

</DOC>
<DOC>
<DOCNO> 102304 </DOCNO>
Orthogonal polynomials associated with root systems


  Let R and S be two irreducible root systems spanning the same vector space
and having the same Weyl group W, such that S (but not necessarily R) is
reduced. For each such pair (R,S) we construct a family of W-invariant
orthogonal polynomials in several variables, whose coefficients are rational
functions of parameters $q,t_1,t_2,...,t_r$, where r (=1,2 or 3) is the number
of W-orbits in R. For particular values of these parameters, these polynomials
give the values of zonal spherical functions on real and p-adic symmetric
spaces. Also when R=S is of type $A_n$, they conincide with the symmetric
polynomials described in I. G. Macdonald, Symmetric Functions and Hall
Polynomials, 2nd edition, Oxford University Press (1995), Chapter VI.

</DOC>
<DOC>
<DOCNO> 10358 </DOCNO>
A problem with the escort distribution representation of nonextensive


  It is pointed out that the Tsallis entropy functional represented in terms of
the escort distribution is not concave of the entropic index $q$ is less than
unity. It is emphasized that the escort distribution is a secondary object
calculated from the basic original distribution.

</DOC>
<DOC>
<DOCNO> 118242 </DOCNO>
Beaming and Jets in GRBs


  The origin of GRBs have been a mystery for almost 30 years. The afterglow
observed in the last few years enabled redshift determination for a handful of
bursts, and the cosmological origin is now firmly established. Though the
distance scale is settled, there still remains orders of magnitude uncertainty
in their rate and in the total energy that is released in the explosion due to
the possibility that the emission is not spherical but jet-like. Contrary to
the GRB itself, the afterglow can be measured up to months and even years after
the burst, and it can provide crucial information on the geometry of the
ejecta. We review the theory of afterglow from jets and discuss the evidence
that at least some of the bursts are not spherical. We discuss the prospects of
polarization measurements, and show that this is a powerful tool in
constraining the geometry of the explosion.

</DOC>
<DOC>
<DOCNO> 40402 </DOCNO>
Pomeron physics: an update


  Key issues in pomeron physics include whether the hard and soft pomerons are
distinct objects, and whether the hard pomeron is already present in amplitudes
at $Q^2=0$. It is urgent to learn how to combine perturbative and
nonperturbative concepts, and to construct a sound theory of perturbative
evolution at small $x$. Other questions are whether screening corrections are
small, and gap survival probabilities large. Finally, do diffractive processes
present a good way to discover the Higgs?

</DOC>
<DOC>
<DOCNO> 70369 </DOCNO>
b --> s \tau^+ \tau^- decay in the two Higgs doublet model with flavor


  We study the decay width and forward-backward asymmetry of the lepton pair
for the inclusive decay b --> s \tau^+ \tau^- in the two Higgs doublet model
with three level flavor changing neutral currents (model III) and analyse the
dependencies of these quantities on the model III parameters, including the
leading order QCD corrections. We found that there is a considerable
enhancement in the decay width and neutral Higgs effects are detectable for
large values of the parameter \bar{\xi}_{N,\tau\tau}^D.

</DOC>
<DOC>
<DOCNO> 99269 </DOCNO>
HyperK\"ahler Potentials in Cohomogeneity Two


  A hyperK\"ahler potential is a function rho that is a K\"ahler potential for
each complex structure compatible with the hyperK\"ahler structure. Nilpotent
orbits in a complex simple Lie algebra are known to carry hyperK\"ahler metrics
admitting such potentials. In this paper, we explicitly calculate the
hyperK\"ahler potential when the orbit is of cohomogeneity two. In some cases,
we find that this structure lies in a one-parameter family of hyperK\"ahler
metrics with K\"ahler potentials, generalising the Eguchi-Hanson metrics in
dimension four.

</DOC>
<DOC>
<DOCNO> 8349 </DOCNO>
Charge and spin ordering in Nd{1/3}Sr{2/3}FeO{3}


  We have investigated the charge and spin ordering in Nd{1/3}Sr{2/3}FeO{3}
with neutron diffraction technique. This sample undergoes a charge ordering
transition accompanying charge disproportionation of 2Fe4+ -> Fe3+ + Fe5+. We
measured the superlattice reflections due to the charge and spin ordering, and
confirmed that charges and spins order simultaneously at Tco = 185 K. The
ordering pattern of charges and spins in this sample can be viewed as three
dimensional stripe order, and is compared with two dimensional stripe order
observed in other transition metal oxides.

</DOC>
<DOC>
<DOCNO> 70406 </DOCNO>
Universality limits on bulk fermions


  The Kaluza-Klein fermion excitations induce mixing between the Standard Model
fermions and loss of universality. The flavour mixing not present in the
Standard Model can be made to vanish aligning the Yukawa couplings and the
Dirac masses of the heavy modes, but universality is only recovered when these
masses go to infinity. This implies a bound on the lightest new heavy quark, M1
\~ 3-5 TeV, which together with the electroweak precision data limits will
allow the Large Hadron Collider to provide a crucial test of the
Randall-Sundrum ansatz for solving the gauge hierarchy.

</DOC>
<DOC>
<DOCNO> 12977 </DOCNO>
Coulomb Interaction and Quantum Transport through a Coherent Scatterer


  An interplay between charge discreteness, coherent scattering and Coulomb
interaction yields nontrivial effects in quantum transport. We derive a real
time effective action and an equivalent quantum Langevin equation for an
arbitrary coherent scatterer and evaluate its current-voltage characteristics
in the presence of interactions. Within our model, at large conductances $G_0$
and low $T$ (but outside the instanton-dominated regime) the interaction
correction to $G_0$ saturates and causes conductance suppression by a universal
factor which depends only on the type of the conductor.

</DOC>
<DOC>
<DOCNO> 151561 </DOCNO>
M(atrix)-Theory Scattering in the Noncommutative (2,0) theory


  We study the Quantum-Mechanics on the hyper-Kahler manifold that is the
blow-up of an $A_1$-singularity. This system is relevant for M(atrix)-theory as
it was conjectured to describe scattering in the "noncommutative" deformation
of a free 5+1D tensor multiplet in the sector with two units of longitudinal
light-like momentum.

</DOC>
<DOC>
<DOCNO> 120952 </DOCNO>
On the Association of Gamma-ray Bursts with Massive Stars: Implications


  Recent evidence appears to link gamma-ray bursts (GRBs) to star-forming
regions in galaxies at cosmological distances. If short-lived massive stars are
the progenitors of GRBs, the rate of events per unit cosmological volume should
be an unbiased tracer (i.e. unaffected by dust obscuration and surface
brightness limits) of the cosmic history of star formation. Here we use
realistic estimates for the evolution of the stellar birthrate in galaxies to
model the number counts, redshift distribution, and time-delay factors of GRBs.
We present luminosity function fits to the BATSE log N-log P relation for
different redshift distributions of the bursts. Our results imply about 1-2
GRBs every one million Type II supernovae, and a characteristic
`isotropic-equivalent' burst luminosity in the range 3-20 x 1e51 ergs/s (for
H_0=65 km/s/Mpc). We compute the rate of multiple imaging of background GRBs
due to foreground mass condensations in a Lambda-dominated cold dark matter
cosmology, assuming that dark halos approximate singular isothermal spheres on
galaxy scales and Navarro-Frenk-White profiles on group/cluster scales, and are
distributed in mass according to the Press-Schechter model. We show that the
expected sensivity increase of Swift relative to BATSE could result in a few
strongly lensed individual bursts detected down to a photon flux of 0.1
phot/s/cm^2 in a 3-year survey. Because of the partial sky coverage, however,
it is unlikely that the Swift satellite will observe recurrent events (lensed
pairs).

</DOC>
<DOC>
<DOCNO> 120665 </DOCNO>
Time-Delay Effect on the cOsmic Background Radiation by Static


  We present a quantitative analysis of the time-delay effect on the cosmic
background radiation (CBR) by static gravitational potential of galaxy
clusters. This is primarily motivated by growing observational evidence that
clusters have essentially experienced no-evolution since redshift $z\approx1$,
indicating that the contribution of a time-dependent potential to CBR
anisotropy discussed in literature could be rather small for the
dynamically-relaxed clusters. Using the softened isothermal sphere model and
the universal density profile for the mass distribution of rich clusters, we
calculate the CBR anisotropy by the time-delay effect and compare it with those
generated by the thermal and kinematic S-Z effects as well as by the transverse
motion of clusters. While it is unlikely that the time-delay effect is
detectable in the current S-Z measurement because of its small amplitude of
$10^{-6}$-$10^{-7}$ and its achromaticity, it nevertheless leads to an
uncertainty of $\sim10%$ in the measurement of the kinematic S-Z effect of
clusters. Future cosmological application of the peculiar velocity of clusters
to be measured through the S-Z effect should therefore take this uncertainty
into account.

</DOC>
<DOC>
<DOCNO> 70509 </DOCNO>
Vector Meson Dominance, Axial Anomaly and the Thermal behavior of


  By using a thermal Finite Energy QCD Sum Rule, we are able to establish the
temperature dependence of the $g_{\omega \rho \pi}(T)$ strong coupling. It
turns out that this coupling decreases as a function of temperature, vanishing
at the critical temperature. This corresponds to a possible deconfining
phenomenological signal. This result, together with the Vector Meson Dominance
(VMD) expression for the amplitude $\pi ^{0} \to \gamma \gamma $, allows us to
establish that this amplitude also vanishes at the critical temperature, in
agreement with previous independent analysis. This results supports, once
again, the validity of VMD at finite temperature. Several posssible scenarios
are discussed. However, if VMD would not hold at finite temperature, then we
will not be able to find a prediction for the thermal behavior of the $\pi ^{0}
\to \gamma \gamma $ amplitude.

</DOC>
<DOC>
<DOCNO> 117499 </DOCNO>
The Energy Output of the Universe


  The total energy emitted by the growth of massive black holes is large and
can be 10-50 per cent of that emitted by stars in the universe. I show how the
X-ray Background provides a good measure of this energy and also why most
accretion power is absorbed and re-emitted in the far infrared band. A model
for the obscured growth of massive black holes is presented which accounts for
both the high absorption and the observed black hole to galaxy spheroid mass
correlation. Future missions should detect the obscured X-ray sources
associated with the growth of massive black holes.

</DOC>
<DOC>
<DOCNO> 100570 </DOCNO>
On the dynamic flows


  It is investigated a possibility of physical interpretation of vector fields
(dynamic flows) in Euclidean spaces of higher dimension. There are analyzed the
methods of measurements of dynamic flows, the characteristics of dynamic flow
and the connection between its differential and integral characteristics. It is
obtained the criterion of local minimality of (n-1)-surfaces that is not
connected with interior geometry of surface. It is analyzed some analogy
between harmonicity of dynamic flows and dynamic principle of nature.

</DOC>
<DOC>
<DOCNO> 117798 </DOCNO>
Analytic model for galaxy and dark matter clustering


  We investigate an analytic model to compute nonlinear power spectrum of dark
matter, galaxies and their cross-correlation. The model is based on
Press-Schechter halos, which cluster and have realistic dark matter profiles.
The total power spectrum is a sum of two contributions, one from correlations
betwen the halos and one from correlations within the same halo. We show that
such a model can give dark matter power spectra which match well with the
results of N-body simulations, provided that concentration parameter decreases
with the halo mass.
 Galaxy power spectrum differs from dark matter power spectrum because pair
weighted number of galaxies increases less rapidly than the halo mass, as
predicted by theoretical models and observed in clusters. In this case the
resulting power spectrum becomes a power law with the slope closed to the
observed. Such a model also predicts a later onset of nonlinear clustering
compared to the dark matter, which is needed to reconcile the CDM models with
the data. Generic prediction of this model is that bias is scale dependent and
nonmonotonic. For red or elliptical galaxies bias in power spectrum may be
scale dependent even on very large scales.
 Our predictions for galaxy-dark matter correlations, which can be observed
through the galaxy-galaxy lensing, show that these cannot be interpreted simply
as an average halo profile of a typical galaxy, because different halo masses
dominate at different scales and because larger halos host more than one
galaxy. We discuss the prospects of using cross-correlations in combination
with galaxy clustering to determine the dark matter power spectrum (ABRIDGED).

</DOC>
<DOC>
<DOCNO> 11451 </DOCNO>
Diffraction of wave packets in space and time


  The phenomenon of wave packet diffraction in space and time is described. It
consists in a diffraction pattern whose spatial location progresses with time.
The pattern is produced by wave packet quantum scattering off an attractive or
repulsive time independent potential. An analytical formula for the pattern at
$t\to\infty$ is derived both in one dimension and in three dimensions. The
condition for the pattern to exist is developed. The phenomenon is shown
numerically and analytically for the Dirac equation in one dimension also. An
experiment for the verification of the phenomenon is described and simulated
numerically.

</DOC>
<DOC>
<DOCNO> 85521 </DOCNO>
Electromagnetic fields around black holes and Meissner effect


  The work on black holes immersed in external stationary magnetic fields is
reviewed in both test-field approximation and within exact solutions. In
particular we pay attention to the effect of the expulsion of the flux of
external fields across charged and rotating black holes which are approaching
extremal states. Recently this effect has been shown to occur for black hole
solutions in string theory and Kaluza-Klein theory.

</DOC>
<DOC>
<DOCNO> 101487 </DOCNO>
Microlocal properties of basic operations in Colombeau algebras


  The Colombeau algebra of generalized functions allows to unrestrictedly carry
out products of distributions. We analyze this operation from a microlocal
point of view, deriving a general inclusion relation for wave front sets of
products in the algebra. Furthermore, we give explicit examples showing that
the given result is optimal, i.e. its assumptions cannot be weakened. Finally,
we discuss the interrelation of these results with the concept of pullback
under smooth maps.

</DOC>
<DOC>
<DOCNO> 151739 </DOCNO>
(2+1)-Dimensional Black Hole with Coulomb-like Field


  A (2+1)-static black hole solution with a nonlinear electric field is
derived. The source to the Einstein equations is a nonlinear electrodynamics,
satisfying the weak energy conditions, and it is such that the energy momentum
tensor is traceless. The obtained solution is singular at the origin of
coordinates. The derived electric field E(r) is given by $E(r)=q/r^2$, thus it
has the Coulomb form of a point charge in the Minkowski spacetime. This
solution describes charged (anti)--de Sitter spaces. An interesting
asymptotically flat solution arises for $\Lambda=0$.

</DOC>
<DOC>
<DOCNO> 72011 </DOCNO>
Sharpening Low-Energy, Standard-Model Tests via Correlation Coefficients


  The correlation coefficients a, A, and B in neutron beta-decay are
proportional to the ratio of the axial-vector to vector weak coupling
constants, g_A/g_V, to leading recoil order. With the advent of the next
generation of neutron decay experiments, the recoil-order corrections to these
expressions become experimentally accessible, admitting a plurality of Standard
Model (SM) tests. The measurement of both a and A, e.g., allows one to test the
conserved-vector-current (CVC) hypothesis and to search for second-class
currents (SCC) independently. The anticipated precision of these measurements
suggests that the bounds on CVC violation and SCC from studies of nuclear
beta-decay can be qualitatively bettered. Departures from SM expectations can
be interpreted as evidence for non-V-A currents.

</DOC>
<DOC>
<DOCNO> 121890 </DOCNO>
Cool helium-rich white dwarfs from the Hamburg/ESO Survey


  We present an analysis of 40 cool helium-rich white dwarfs found in the
Hamburg/ESO survey. They were selected for follow-up spectroscopy because of
their U-B colour below -0.18, the absence of strong absorption lines, and a
continuum shape similar to that of a quasar. Effective temperatures for
individual stars were determined by fitting model atmospheres of nearly pure
helium with a small admixture of hydrogen. As a consequence of the selection
criteria all but one sample stars have Teff below 20000 K. Four stars clearly
show helium and hydrogen lines in their spectra. In the spectra of another
three, helium, hydrogen, and metal lines can be detected. For these stars
hydrogen and metal abundances were also determined by fitting appropriate model
atmospheres containing these elements. Seven sample stars most likely have
helium-rich atmospheres but do not show any helium lines. They either have
featureless spectra or show calcium lines.

</DOC>
<DOC>
<DOCNO> 68803 </DOCNO>
Order alpha^3 ln(1/alpha) Corrections to Positronium Decays


  The logarithmically enhanced alpha^3 ln(1/alpha) corrections to the para- and
orthopositronium decay widths are calculated in the framework of dimensionally
regularized nonrelativistic quantum electrodynamics.In the case of
parapositronium, the correction is negative, approximately doubles the effect
of the leading logarithmic alpha^3 ln^2(1/alpha) one, and is comparable to the
nonlogarithmic O(alpha^2) one. As for orthopositronium, the correction is
positive and almost cancels the alpha^3 ln^2(1/alpha) one. The uncertainties in
the theoretical predictions for the decay widths are reduced.

</DOC>
<DOC>
<DOCNO> 70139 </DOCNO>
Final State Interactions in Kaon Decays


  We quantify the important effect of strong final state interactions in the
weak $K\to 2\pi$ amplitudes, using the measured $\pi$-$\pi$ phase shifts with
J=0 and $I=0,2$. The main results of this analysis, with their implications for
$\epsilon'/\epsilon$ and the $\Delta I =1/2$ rule, have been already presented
in a previous paper [1]. Here we provide a detailed formal derivation of those
results and further discuss the Standard Model prediction of
$\epsilon'/\epsilon$.

</DOC>
<DOC>
<DOCNO> 122097 </DOCNO>
Spiral structure parameters in the solar neighbourhood


  Two samples of O- and B-type stars and Cepheids with Hipparcos data have been
used to characterize galactic rotation and spiral arm kinematics in the solar
neighbourhood. An extensive set of simulations has been performed in order to
assess the capabilities of the method and its sensitivity to sample errors and
biases in the adopted parameters.

</DOC>
<DOC>
<DOCNO> 84155 </DOCNO>
Energy conditions and their cosmological implications


  The energy conditions of general relativity permit one to deduce very
powerful and general theorems about the behaviour of strong gravitational
fields and cosmological geometries. However, the energy conditions these
theorems are based on are beginning to look a lot less secure than they once
seemed: (1) there are subtle quantum effects that violate all of the energy
conditions, and more tellingly (2), there are also relatively benign looking
classical systems that violate all the energy conditions. This opens up a
Pandora's box of rather disquieting possibilities --- everything from negative
asymptotic mass, to traversable wormholes, to warp drives, up to and including
time machines.

</DOC>
<DOC>
<DOCNO> 117582 </DOCNO>
Chandra Observation of Abell 2142: Survival of Dense Subcluster Cores in


  We use Chandra data to map the gas temperature in the central region of the
merging cluster A2142. The cluster is markedly nonisothermal; it appears that
the central cooling flow has been disturbed but not destroyed by a merger. The
X-ray image exhibits two sharp, bow-shaped, shock-like surface brightness edges
or gas density discontinuities. However, temperature and pressure profiles
across these edges indicate that these are not shock fronts. The pressure is
reasonably continuous across these edges, while the entropy jumps in the
opposite sense to that in a shock (i.e. the denser side of the edge has lower
temperature, and hence lower entropy). Most plausibly, these edges delineate
the dense subcluster cores that have survived a merger and ram pressure
stripping by the surrounding shock-heated gas.

</DOC>
<DOC>
<DOCNO> 85014 </DOCNO>
The Speed of Light and the Fine Structure Constant


  The fine structure constant $\alpha $ includes the speed of light as given by
$\alpha =\frac{e^{2}}{4\pi \epsilon_{0}c\hbar}$. It is shown here that,
following a $TH\epsilon \mu $ formalism, interpreting the permittivity
$\epsilon_{0}$ and permeabiliy $\mu_{0}$ of free space under Lorentz local and
position invariance, this is not the case. The result is a new expression as
$\alpha =\frac{e^{2}}{4\pi \hbar}$ in a new system of units for the charge that
preserves local and position invariance. Hence, the speed of light does not
explicitly enter in the constitution of the fine structure constant. The new
expressions for the Maxwell's equations are derived and some cosmological
implications discussed.

</DOC>
<DOC>
<DOCNO> 11021 </DOCNO>
Stable and Metastable vortex states and the first order transition


  The peak effect in weakly pinned superconductors is accompanied by metastable
vortex states. Each metastable vortex configuration is characterized by a
different critical current density J_c, which mainly depends on the past
thermomagnetic history of the superconductor. A recent model [G. Ravikumar, et
al, Phys. Rev. B 61, R6479 (2000)] proposed to explain the history dependent
J_c postulates a stable state of vortex lattice with a critical current density
J_c^{st}, determined uniquely by the field and temperature. In this paper, we
present evidence for the existence of the stable state of the vortex lattice in
the peak effect region of 2H-NbSe_2. It is shown that this stable state can be
reached from any metastable vortex state by cycling the applied field by a
small amplitude. The minor magnetization loops obtained by repeated field
cycling allow us to determine the pinning and "equilibrium" properties of the
stable state of the vortex lattice at a given field and temperature
unambiguously. The data imply the occurence of a first order phase transition
from an ordered phase to a disordered vortex phase across the peak effect.

</DOC>
<DOC>
<DOCNO> 69837 </DOCNO>
The Singlet g_2 Structure Function in the Next-to-Leading Order


  Following a previous study of the one-loop factorization of the nonsinglet
$g_2$ structure function of the nucleon, we present in this paper the
next-to-leading order coefficient functions in the singlet sector. To obtain
the result, the partonic processes of virtual Compton scattering off two and
three "on-shell" gluons are calculated. A key step in achieving the correct
factorization is to separate the correct twist-two contribution. The
Burkardt-Cottingham sum rule is nominally satisfied at this order.

</DOC>
<DOC>
<DOCNO> 100168 </DOCNO>
Une q - sp\'ecialisation pour les fonctions sym\'etriques monomiales


  We obtain the specialization of monomial symmetric functions on the alphabet
(a-b)/(1-q). This gives a remarkable algebraic identity, and four new
developments for the Macdonald polynomial associated with a row. The proofs are
given in the framework of $\lambda$-ring theory.

</DOC>
<DOC>
<DOCNO> 99577 </DOCNO>
Metastability of Breather Modes of Time-Dependent Potentials


  We study the solutions of linear Schroedinger equations in which the
potential energy is a periodic function of time and is sufficiently localized
in space. We consider the potential to be close to one that is time periodic
and yet explicitly solvable. A large family of such potentials has been
constructed and the corresponding Schroedinger equation solved by Miller and
Akhmediev. Exact bound states, or breather modes, exist in the unperturbed
problem and are found to be generically metastable in the presence of small
periodic perturbations. Thus, these states are long-lived but eventually decay.
On a time scale of order $\epsilon^{-2}$, where $\epsilon$ is a measure of the
perturbation size, the decay is exponential, with a rate of decay given by an
analogue of Fermi's golden rule. For times of order $\epsilon^{-1}$ the
breather modes are frequency shifted. This behavior is derived first by
classical multiple-scale expansions, and then in certain circumstances we are
able to apply the rigorous theory developed by Soffer and Weinstein and
extended by Kirr and Weinstein to justify the expansions and also provide
longer-time asymptotics that indicate eventual dispersive decay of the bound
states with behavior that is algebraic in time. As an application, we use our
techniques to study the frequency dependence of the guidance properties of
certain optical waveguides. We supplement our results with numerical
experiments.

</DOC>
<DOC>
<DOCNO> 118029 </DOCNO>
The Fraction of High Redshift Galaxies in Deep Infrared Selected Field


  Recent results on the incidence of red galaxies in a > 100 square arcminute
field galaxy survey to K=20 and a K=22 survey of the Hubble Deep Field are
presented. We argue that a simple photometric redshift indicator, based on J-K
color and supported by spectroscopic results obtained with Keck, gives a
reliable lower limit of ~25% for the fraction of z>1 galaxies in the 100 square
arcminute survey. This fraction is substantially higher than found in previous
smaller samples, and is at least as consistent with predictions for pure
luminosity evolution as with those for hierarchical models. The same technique
yields a very low fraction for the HDF, which appears to be unusually
underabundant in red galaxies.

</DOC>
<DOC>
<DOCNO> 122775 </DOCNO>
A comparison of the anelastic and subseismic approximations for


  A comparative study of the properties of the anelastic and subseismic
approximations is presented. The anelastic approximation is commonly used in
astrophysics in compressible convection studies whereas the subseismic
approximation comes from geophysics where it is used to describe long-period
seismic oscillations propagating in the Earth's outer fluid core. Both
approximations aim at filtering out the acoutic waves while retaining the
density variations of the equilibrium configuration. However, they disagree on
the form of the equation of mass conservation. We show here that the anelastic
approximation is in fact the only consistent approximation as far as stellar
low-frequency oscillations are concerned. We also show that this approximation
implies Cowling's approximation which neglects perturbations of the gravity
field. Examples are given to assert the efficiency of the anelastic
approximation.

</DOC>
<DOC>
<DOCNO> 11762 </DOCNO>
Iterated fully coordinated percolation on a square lattice


  We study, on a square lattice, an extension to fully coordinated percolation
which we call iterated fully coordinated percolation. In fully coordinated
percolation, sites become occupied if all four of its nearest neighbors are
also occupied. Repeating this site selection process again yields the iterated
fully coordinated percolation model. Our results show a substantial enhancement
in the size of highly connected regions after each iteration (from ordinary to
fully coordinated and then to iterated fully coordinated percolation). However,
using Monte Carlo methods to determine the static critical exponents and normal
mode analyses to determine the dynamic critical exponents, our results indicate
that the ordinary, fully coordinated, and iterated fully coordinated
percolation models belong to the same universality class. This is in contrast
to our previous results [*] wherein a different universality class dynamically
(but not statically) for fully coordinated percolation was indicated, though
the differences in the dynamic exponents were small. A possible cause might be
the different methods of generating clusters, i.e., in this work clusters were
generated statically in square lattices while in our previous work clusters
were grown dynamically, for studying the dynamic critical exponents.
  * E. Cuansing, J. H. Kim and H. Nakanishi, Phys. Rev. E, 60, 3670 (1999).

</DOC>
<DOC>
<DOCNO> 72019 </DOCNO>
Comparision of the Pion Emission Function in Hadron-Hadron and Heavy-Ion


  Combining results on single-particle distributions with those of the
 Bose-Einstein correlation analysis in the same experiment, the space-time
emission function is extracted as a function of time and longitudinal
coordinate, as well as a function of transverse coordinates.
 While the former function resembles a boomerang for both types of collision
(only shifted in the time direction due to the larger freeze-out time in
heavy-ion collisions), the latter function is Gaussian for heavy-ion
collisions, but ring-shaped for hadron-hadron collisions.

</DOC>
<DOC>
<DOCNO> 69273 </DOCNO>
Bulk U(1) Messenger


  We propose a new U(1) gauge interaction in the bulk in higher dimensional
spacetime, which transmits supersymmetry-breaking effects on the hidden brane
to the observable our brane. We find that rather small gauge coupling constant
of U(1)_{bulk}, $\alpha_{bulk} \simeq 5 \times 10^{-4}$, is required for a
successful phenomenology. This result implies the compactification length $L$
of the extra dimension to be $L^{-1} \simeq 2 \times 10^{15}GeV$ for
(4+1)-dimensional spacetime. This large compactification length $L$ is a
crucial ingredient to suppress unwanted flavor-changing neutral currents and
hence our proposal is very consistent with the Randall-Sundrum brane-world
scenario.

</DOC>
<DOC>
<DOCNO> 69687 </DOCNO>
Radiative corrections to the semileptonic Dalitz plot with angular


  We obtain a model-independent expression for the Dalitz plot of semileptonic
decays of polarized hyperons including radiative corrections to order alpha and
neglecting terms of order (alpha q)/(pi M_1), where q is the four-momentum
transfer and M_1 is the mass of the decaying hyperon. We specialize our results
to exhibit the correlation between the charged-lepton momentum and the spin of
the decaying hyperon. We present results for the three-body region of the
Dalitz plot and for the complete Dalitz plot (which includes the four-body
region). From these results we also obtain the corresponding radiative
corrections to the integrated lepton spin-asymmetry coefficient. Our formulas
are valid for charged as well as for neutral decaying hyperons and are
appropriate for model-independent experimental analysis whether the real photon
is discriminated or not.

</DOC>
<DOC>
<DOCNO> 118280 </DOCNO>
Photometric catalog of nearby globular clusters (I)


  We present the first part of the first large and homogeneous CCD
color-magnitude diagram (CMD) data base, comprising 52 nearby Galactic globular
clusters (GGC) imaged in the V and I bands using only two telescopes (one for
each hemisphere). The observed clusters represent 75% of the known Galactic
globulars with (m-M)v<=16.15 mag, cover most of the globular cluster
metallicity range (-2.2 <= [Fe/H] <= -0.4), and span Galactocentric distances
from ~1.2 to ~18.5 kpc.
  In this paper, the CMDs for the 39 GGCs observed in the southern hemisphere
are presented. The remaining 13 northern hemisphere clusters of the catalog are
presented in a companion paper. For four clusters (NGC 4833, NGC 5986, NGC
6543, and NGC 6638) we present for the first time a CMD from CCD data. The
typical CMD spans from the 22nd V magnitude to the tip of the red giant branch.
Based on a large number of standard stars, the absolute photometric calibration
is reliable to the ~0.02 mag level in both filters.
  This catalog, because of its homogeneity, is expected to represent a useful
data base for the measurement of the main absolute and relative parameters
characterizing the CMD of GGCs.

</DOC>
<DOC>
<DOCNO> 170155 </DOCNO>
Fast parallel circuits for the quantum Fourier transform


  We give new bounds on the circuit complexity of the quantum Fourier transform
(QFT). We give an upper bound of O(log n + log log (1/epsilon)) on the circuit
depth for computing an approximation of the QFT with respect to the modulus 2^n
with error bounded by epsilon. Thus, even for exponentially small error, our
circuits have depth O(log n). The best previous depth bound was O(n), even for
approximations with constant error. Moreover, our circuits have size O(n log
(n/epsilon)). We also give an upper bound of O(n (log n)^2 log log n) on the
circuit size of the exact QFT modulo 2^n, for which the best previous bound was
O(n^2).
  As an application of the above depth bound, we show that Shor's factoring
algorithm may be based on quantum circuits with depth only O(log n) and
polynomial-size, in combination with classical polynomial-time pre- and
post-processing. In the language of computational complexity, this implies that
factoring is in the complexity class ZPP^BQNC, where BQNC is the class of
problems computable with bounded-error probability by quantum circuits with
poly-logarithmic depth and polynomial size.
  Finally, we prove an Omega(log n) lower bound on the depth complexity of
approximations of the QFT with constant error. This implies that the above
upper bound is asymptotically optimal (for a reasonable range of values of
epsilon).

</DOC>
<DOC>
<DOCNO> 122470 </DOCNO>
Stellar Pollution in the Solar Neighborhood


  We study spectroscopically determined iron abundances of 642 solar-type stars
to search for the signature of accreted iron-rich material. We find that the
metallicity [Fe/H] of a subset of 466 main sequence stars, when plotted as a
function of stellar mass, mimics the pattern seen in lithium abundances in open
clusters. Using Monte Carlo models we find that, on average, these stars have
accreted about 0.4 Earth masses of iron while on the main sequence. A much
smaller sample of 19 stars in the Hertzsprung gap, which are slightly evolved
and whose convection zones are significantly more massive, have lower average
[Fe/H], and their metallicity shows no clear variation with stellar mass. These
findings suggest that terrestrial-type material is common around solar type
stars.

</DOC>
<DOC>
<DOCNO> 12058 </DOCNO>
Correcting the quantum clock: conditional sojourn times


  Can the quantum-mechanical sojourn time be clocked without the clock
affecting the sojourn time? Here we re-examine the previously proposed
non-unitary clock, involving absorption/amplification by an added infinitesimal
imaginary potential($iV_{i}$), and find it {\it not} to preserve, in general,
the positivity of the sojourn time, conditional on eventual reflection or
transmission. The sojourn time is found to be affected by the scattering
concomitant with the mismatch, however small, due to the very clock
potential($iV_{i}$) introduced for the purpose, as also by any prompt
scattering involving partial waves that have not traversed the region of
interest. We propose a formal procedure whereby the sojourn time so clocked can
be corrected for these spurious scattering effects. The resulting conditional
sojourn times are then positive definite for an arbitrary potential, and have
the proper high- and low-energy limits.

</DOC>
<DOC>
<DOCNO> 10603 </DOCNO>
Permeability of self-affine rough fractures


  The permeability of two-dimensional fractures with self-affine fractal
roughness is studied via analytic arguments and numerical simulations. The
limit where the roughness amplitude is small compared with average fracture
aperture is analyzed by a perturbation method, while in the opposite case of
narrow aperture, we use heuristic arguments based on lubrication theory.
Numerical simulations, using the lattice Boltzmann method, are used to examine
the complete range of aperture sizes, and confirm the analytic arguments.

</DOC>
<DOC>
<DOCNO> 117624 </DOCNO>
Supermassive Black Holes Can Hardly Be "Silent"


  There is now ample evidence that most - perhaps all - galactic spheroids host
a supermassive BH at their center. This has been assessed using a variety of
observational techniques, from stellar and/or gas dynamics to megamasers. Yet
another promising technique is offered by the case of the Virgo elliptical NGC
4552, in which early HST/FOC observations revealed a central low-luminosity
flare. Subsequent HST/FOS observations with a 0.21 arcsec aperture have
revealed a rich emission-line spectrum with broad and narrow components with
FWHM of 3000 and 700 km/s, respectively. This variable, mini-AGN at the center
of NGC 4552 is most naturally the result of a sporadic accretion event on a
central BH. It has a H$\alpha$ luminosity of only $\sim 10,000 \lsun$, making
it the likely, intrinsically faintest AGN known today. Only thanks to the
superior resolution of HST such a faint object has been discovered and studied
in detail, but adaptive optics systems on large ground-based telescopes may
reveal in the future that a low level of accretion onto central massive BHs is
an ubiquitous phenomenon among galactic spheroids. FOC/FOS observations of a
central spike in NGC 2681 reveal several analogies with the case of NGC 4552,
while yet another example is offered by a recent exciting finding with STIS by
R.W. O'Connell in NGC 1399, the third galaxy in our original program.
garchingbh

</DOC>
<DOC>
<DOCNO> 151934 </DOCNO>
Noncommutative Geometry from String Theory: Annulus Corrections


  We develop a method in which it is possible to calculate one loop corrections
to the noncommutativity parameter for open strings in a background F field. We
reproduce known disk level results, and find that annulus corrections give the
same structure multiplied by a constant due to the tachyon.

</DOC>
<DOC>
<DOCNO> 150728 </DOCNO>
Twist decomposition of nonlocal light-cone operators II: General tensors


  A group theoretical procedure, introduced earlier (hep-th/9901090), to
decompose bilocal light-ray operators into (harmonic) operators of definite
twist is applied to the case of arbitrary 2nd rank tensors. As a generic
example the bilocal gluon operator is considered which gets contributions of
twist-2 up to twist-6 from four different symmetry classes characterized by
conrresponding Young tableaus; also the twist decomposition of the related
vector and scalar operators is considered. In addition, we extend these reselts
to various trilocal light-ray operators, like the Shuryak-Vainshtein, the
three-gluon and the four-quark operators, which are required for the
consideration of higher twist distribution amplitudes. The present results rely
on the knowledge of harmonic tensor polynomials of any order n which habe been
determined up to the case of 2nd rank symmetric tensors for arbitrary
space-time dimension.

</DOC>
<DOC>
<DOCNO> 118593 </DOCNO>
The Mid-Infrared Spectra of Interacting Galaxies: From ISO to SIRTF


  We present mid-infrared (5--16micron) images and spectra of a sequence of
interacting galaxies, observed by ISOCAM. The galaxies were selected as being
at progressive stages in the time evolution of a merging event, following what
is known as Toomre's ``merger sequence'', and having no detected contribution
from an active galactic nucleus (AGN) in their mid-infrared spectrum. To trace
the intensity of the global star formation in those galaxies, we use the ratio
of the 15micron to 7micron flux. Our analysis indicates that this ratio
increases from ~1 to ~5 as galaxies move from the pre-starburst to the
merging/starburst phase only to decrease to ~1 again in the post-starburst
phase of the evolved merger remnants. Moreover, we find that the variation of
this ratio is well correlated with the one of the IRAS 25/12 and 60/100 flux
ratios. The potential to test and improve upon these results using the Infrared
Spectrograph (IRS) on board SIRTF is discussed.

</DOC>
<DOC>
<DOCNO> 68852 </DOCNO>
An automatized algorithm to compute infrared divergent multi-loop


  We describe a constructive procedure to separate overlapping infrared
divergences in multi-loop integrals. Working with a parametric representation
in D=4-2*epsilon dimensions, adequate subtractions lead to a Laurent series in
epsilon, where the coefficients of the pole- and finite terms are sums of
regular parameter integrals which can be evaluated numerically. We fully
automatized this algorithm by implementing it into algebraic manipulation
programs and applied it to calculate numerically some nontrivial 2-loop 4-point
and 3-loop 3-point Feynman diagrams. Finally, we discuss the applicability of
our method to phenomenologically relevant multi--loop calculations such as the
NNLO QCD corrections for e^+e^- --> 3 jets.

</DOC>
<DOC>
<DOCNO> 151336 </DOCNO>
S^3 Skyrmions and the Rational Map Ansatz


  This paper discusses multi-skyrmions on the 3-sphere with variable radius L
using the rational map ansatz. For baryon number B = 3,...,9 this ansatz
produces the lowest energy solutions known so far. By considering the geometry
of the model we find an approximate analytic formula for the shape function.
This provides an insight why skyrmions have a shell-like structure.

</DOC>
<DOC>
<DOCNO> 117514 </DOCNO>
Discovery of a Brown Dwarf Companion to Gliese 570ABC: A 2MASS T Dwarf


  We report the discovery of a widely separated (258$\farcs3\pm0\farcs$4) T
dwarf companion to the Gl 570ABC system. This new component, Gl 570D, was
initially identified from the Two Micron All Sky Survey (2MASS). Its
near-infrared spectrum shows the 1.6 and 2.2 $\micron$ CH$_4$ absorption bands
characteristic of T dwarfs, while its common proper motion with the Gl 570ABC
system confirms companionship. Gl 570D (M$_J$ = 16.47$\pm$0.07) is nearly a
full magnitude dimmer than the only other known T dwarf companion, Gl 229B, and
estimates of L = (2.8$\pm$0.3)x10$^{-6}$ L$_{\sun}$ and T$_{eff}$ = 750$\pm$50
K make it significantly cooler and less luminous than any other known brown
dwarf companion. Using evolutionary models by Burrows et al. and an adopted age
of 2-10 Gyr, we derive a mass estimate of 50$\pm$20 M$_{Jup}$ for this object.

</DOC>
<DOC>
<DOCNO> 13716 </DOCNO>
Phase Fluctuations and Pseudogap Phenomena


  This article reviews the current status of precursor superconducting phase
fluctuations as a possible mechanism for pseudogap formation in
high-temperature superconductors. In particular we compare this approach which
relies on the two-dimensional nature of the superconductivity to the often used
$T$-matrix approach. Starting from simple pairing Hamiltonians we present a
broad pedagogical introduction to the BCS-Bose crossover problem. The finite
temperature extension of these models naturally leads to a discussion of the
Berezinskii-Kosterlitz-Thouless superconducting transition and the related
phase diagram including the effects of quantum phase fluctuations and
impurities. We stress the differences between simple Bose-BCS crossover
theories and the current approach where one can have a large pseudogap region
even at high carrier density where the Fermi surface is well-defined. The
Green's function and its associated spectral function, which explicitly show
non-Fermi liquid behaviour, is constructed in the presence of vortices. Finally
different mechanisms including quasi-particle-vortex and vortex-vortex
interactions for the filling of the gap above $T_c$ are considered.

</DOC>
<DOC>
<DOCNO> 84331 </DOCNO>
The Fefferman-Graham Ambiguity and AdS Black Holes


  Asymptotically anti-de Sitter space-times in pure gravity with negative
cosmological constant are described, in all space-time dimensions greater than
two, by classical degrees of freedom on the conformal boundary at space-like
infinity. Their effective boundary action has a conformal anomaly for even
dimensions and is conformally invariant for odd ones. These degrees of freedom
are encoded in traceless tensor fields in the Fefferman-Graham asymptotic
metric for any choice of conformally flat boundary and generate all
Schwarzschild and Kerr black holes in anti-de Sitter space-time. We argue that
these fields describe components of an energy-momentum tensor of a boundary
theory and show explicitly how this is realized in 2+1 dimensions. There, the
Fefferman-Graham fields reduce to the generators of the Virasoro algebra and
give the mass and the angular momentum of the BTZ black holes. Their local
expression is the Liouville field in a general curved background.

</DOC>
<DOC>
<DOCNO> 120543 </DOCNO>
Stellar Companions and the Age of HD 141569 and its Circumstellar Disk


  We investigate the stellar environment of the Beta Pictoris-like star HD
141569 with optical spectroscopy and near infrared imaging. The B9.5Ve primary,
and an M2 and an M4 type star both located in projection less than nine
arseconds away have the same radial velocity and proper motion and therefore
almost certainly form a triple star system. From their x-ray flux, lithium
absorption and location on pre-main-sequence evolutionary tracks, the
companions appear to be 5 Myr old. HD 141569 A is now one of the few stars with
a circumstellar disk that has a well-determined age. The circumstellar disk is
composed of secondary debris material (Fisher et al. 2000), thus placing an
upper limit on the time needed for disk processing. These three stars may be
part of an association of young stars.

</DOC>
<DOC>
<DOCNO> 72048 </DOCNO>
Hyperon Beta-Decay Analysis and the Recent KTeV Data


  The analysis of hyperon semi-leptonic decay data is addressed with reference
to SU(3) breaking and isospin mixing between Lambda^O and Sigma^O. Various
approaches to SU(3) breaking are discussed and compared. The phenomenological
implications of Lambda^0-Sigma^0 mixing are not to be underestimated: it can
induce vector couplings in decays otherwise purely axial and may also modify
rates. In regard of the KTeV data on Xi^0O -> Sigma^+ e antineutrino,
predictions are presented and the impact of present a future data on the
extraction of F and D is also examined. In addition, the implications of the
new data for the use of octet baryon beta decays in determining V_us are
considered.

</DOC>
<DOC>
<DOCNO> 170613 </DOCNO>
Dynamical analysis of the buildup process near resonance


  The time evolution of the buildup process inside a double-barrier system for
off-resonance incidence energies is studied by considering the analytic
solution of the time dependent Schr\"{o}dinger equation with cutoff plane wave
initial conditions. We show that the buildup process exhibits invariances under
arbitrary changes on the system parameters, which can be successfully described
by a simple and easy-to-use one-level formula. We find that the buildup of the
off-resonant probability density is characterized by an oscillatory pattern
modulated by the resonant case which governs the duration of the transient
regime. This is evidence that off-resonant and resonant tunneling are two
correlated processes, whose transient regime is characterized by the same
transient time constant of two lifetimes.

</DOC>
<DOC>
<DOCNO> 71583 </DOCNO>
Probing Neutral Gauge Boson Self-interactions in ZZ Production at the


  We present an analysis of ZZ production at the upgraded Fermilab Tevatron for
general ZZZ and ZZ-gamma couplings. Achievable limits on these couplings are
shown to be a significant improvement over the limits currently obtained by LEP
II.

</DOC>
<DOC>
<DOCNO> 70733 </DOCNO>
Effective dissipative dynamics for polarized photons


  In the framework of open quantum systems, the propagation of polarized
photons can be effectively described using quantum dynamical semigroups. These
extended time-evolutions induce irreversibility and dissipation. Planned, high
sensitive experiments, both in the laboratory and in space, will be able to put
stringent bounds on these non-standard effects.

</DOC>
<DOC>
<DOCNO> 69327 </DOCNO>
Neutrino Majorana Mass and Baryon Number of the Universe below the


  If the neutrino is Majorana type and the electroweak phase transition is
second or weak first order, neutrino-induced interactions together with
sphaleron transitions have the potential to erase a previously generated baryon
asymmetry of the universe. Taking correctly into account the evolution of the
vacuum expectation of the Higgs field the effective light neutrino masses are
constrained to be lighter than order 10 MeV, while the effective heavy masses
are constrained to be heavier than order 10^7 GeV.

</DOC>
<DOC>
<DOCNO> 68955 </DOCNO>
Complementary Ansatz for the neutrino mass matrix


  We propose a simple Ansatz for the three generation neutrino mass matrix
$M_\nu$ which is motivated from an SO(10) grand unified theory. The Ansatz can
be combined with information from neutrino oscillation experiments and bounds
on neutrinoless double beta decay to determine the neutrino masses themselves
and to reconstruct, with some assumptions, the matrix $ M_\nu $ .

</DOC>
<DOC>
<DOCNO> 123272 </DOCNO>
Dynamics of embedded bars and the connection with AGN. I. ISAAC/VLT


  We present new stellar kinematical profiles of four galaxy hosts of active
galactic nuclei, using the CO bandhead around 2.3 micron with the ISAAC/VLT
spectrograph. We find that the nuclear bars or discs, embedded in large-scale
primary bars, have all a decoupled kinematics, in the sense that the maximum of
the rotational velocity occurs in the nuclear region. In three cases (NGC 1097,
NGC 1808 and NGC 5728), the velocity dispersion displays a significant drop at
the nucleus, a rarely observed phenomenon. We also detect kinematical
asymmetries (m=1 mode) along the nuclear bar major-axis of NGC 1808 and NGC
5728, dynamical counterparts of corresponding asymmetries in the surface
brightness. We have derived simple dynamical models in an attempt to fit the
kinematics of each galaxy and reconstruct the full velocity field. For all four
targets, the fits are good, and confirm the presence of the decoupled nuclear
components. These models cannot however reproduce the observed central drop in
the dispersion. We suggest that this drop is due to a transient cold nuclear
disc, fuelled by gas inflow along the bar, that has recently formed new stars.

</DOC>
<DOC>
<DOCNO> 99321 </DOCNO>
Slow Motion of Charges Interacting Through the Maxwell Field


  We study the Abraham model for $N$ charges interacting with the Maxwell
field. On the scale of the charge diameter, $R_{\phi}$, the charges are a
distance $\eps^{-1}R_{\phi}$ apart and have a velocity $\sqrt{\eps} c$ with
$\eps$ a small dimensionless parameter. We follow the motion of the charges
over times of the order $\eps^{-3/2}R_{\phi}/c$ and prove that on this time
scale their motion is well approximated by the Darwin Lagrangian. The mass is
renormalized. The interaction is dominated by the instantaneous Coulomb forces,
which are of the order $\eps^{2}$. The magnetic fields and first order
retardation generate the Darwin correction of the order $\eps^{3}$. Radiation
damping would be of the order $\eps^{7/2}$.

</DOC>
<DOC>
<DOCNO> 11782 </DOCNO>
Entropic measure of spatial disorder for systems of finite-sized objects


  We consider the relative configurational entropy per cell S_Delta as a
measure of the degree of spatial disorder for systems of finite-sized objects.
It is highly sensitive to deviations from the most spatially ordered reference
configuration of the objects. When applied to a given binary image it provides
the quantitatively correct results in comparison to its point object version.
On examples of simple cluster configurations, two-dimensional Sierpinski
carpets and population of interacting particles, the behaviour of S_Delta is
compared with the normalized information entropy H' introduced by Van Siclen
[Phys. Rev. E 56, (1997) 5211]. For the latter example, the additional
middle-scale features revealed by our measure may indicate for the traces of
self-similar structure of the weakly ramified clusters. In the thermodynamic
limit, the formula for S_Delta is also given.

</DOC>
<DOC>
<DOCNO> 11725 </DOCNO>
Finite Temperature Magnetism in Fractional Quantum Hall Systems:


  Using the Hamiltonian formulation of Composite Fermions developed recently,
the temperature dependence of the spin polarization is computed for the
translationally invariant fractional quantum Hall states at $\nu=1/3$ and
$\nu=2/5$ in two steps. In the first step, the effect of particle-hole
excitations on the spin polarization is computed in a Composite Fermion
Hartree-Fock approximation. The computed magnetization for $\nu=1/3$ lies above
the experimental results for intermediate temperatures indicating the
importance of long wavelength spin fluctuations which are not correctly treated
in Hartree-Fock. In the second step, spin fluctuations beyond Hartree-Fock are
included for $\nu=1/3$ by mapping the problem on to the coarse-grained
continuum quantum ferromagnet. The parameters of the effective continuum
quantum ferromagnet description are extracted from the preceding Hartree-Fock
analysis. After the inclusion of spin fluctuations in a large-N approach, the
results for the finite-temperature spin polarization are in quite good
agreement with the experiments.

</DOC>
<DOC>
<DOCNO> 151277 </DOCNO>
A model for time-dependent cosmological constant


  We present a model for a spacetime dependent cosmological {\it constant}. We
make a realization of this model based on a possible quantum aspects of the
initial stage of the universe and relate the cosmological constant with the
chiral anomaly.

</DOC>
<DOC>
<DOCNO> 11498 </DOCNO>
Tunneling of the Mn12-acetate spin cluster


  The term in spin Hamiltonian, which determines the quantum tunneling rate in
Mn12, is measured with neutron scattering. It is much smaller than previously
reported values. This may imply that other mechanisms such as hyperfine fields
may be more important in driving the tunneling.

</DOC>
<DOC>
<DOCNO> 99881 </DOCNO>
Density of integral points on algebraic varieties


  We study the distribution of integral points on log varieties.

</DOC>
<DOC>
<DOCNO> 84834 </DOCNO>
Effective field theory of slowly-moving "extreme black holes"


  We consider the non-relativistic effective field theory of ``extreme black
holes'' in the Einstein-Maxwell-dilaton theory with an arbitrary dilaton
coupling. We investigate finite-temperature behavior of gas of ``extreme black
holes'' using the effective theory. The total energy of the classical many-body
system is also derived.

</DOC>
<DOC>
<DOCNO> 117371 </DOCNO>
Evidence for TeV gamma-ray emission from the shell type SNR


  We report the results of TeV gamma-ray observations of the shell type SNR
RXJ1713.7-3946 (G347.3-0.5). The discovery of strong non-thermal X-ray emission
from the northwest part of the remnant strongly suggests the existence of
electrons with energies up to 100 TeV in the remnant, making the SNR a good
candidate TeV gamma-ray source. We observed RXJ1713.7-3946 from May to August
1998 with the CANGAROO 3.8m atmospheric imaging Cerenkov telescope and obtained
evidence for TeV gamma-ray emission from the NW rim of the remnant with the
significance of 5.6 sigma. The observed TeV gamma-ray flux from the NW rim
region was estimated to be (5.3 +/- 0.9[statistical] +/- 1.6[systematic]) *
10^{-12} photons cm^{-2} s^{-1} at energies >= 1.8 +/- 0.9 TeV. The data
indicate that the emitting region is much broader than the point spread
function of our telescope. The extent of the emission is consistent with that
of hard X-rays observed by ASCA. This TeV gamma-ray emission can be attributed
to the Inverse Compton scattering of the Cosmic Microwave Background Radiation
by shock accelerated ultra-relativistic electrons. Under this assumption, a
rather low magnetic field of 11 micro gauss is deduced for the remnant from our
observation.

</DOC>
<DOC>
<DOCNO> 151354 </DOCNO>
Infrared singularities in the renormalization group flow of Yang-Mills


  It is shown, by explicit calculation in the axial gauge, that the
renormalization group flow for the Wilson loop in perturbation theory does
exhibit singularities and consequently it can not eventually reproduce the
gauge invariant result, when the infrared cut off is removed

</DOC>
<DOC>
<DOCNO> 85563 </DOCNO>
Quantum Fluctuations of Radiation Pressure


  Quantum fluctuations of electromagnetic radiation pressure are discussed. We
use an approach based on the quantum stress tensor to calculate the
fluctuations in velocity and position of a mirror subjected to electromagnetic
radiation. Our approach reveals that radiation pressure fluctuations are due to
a cross term between vacuum and state dependent terms in a stress tensor
operator product. Thus observation of these fluctuations would entail
experimental confirmation of this cross term. We first analyze the pressure
fluctuations on a single, perfectly reflecting mirror, and then study the case
of an interferometer. This involves a study of the effects of multiple bounces
in one arm, as well as the correlations of the pressure fluctuations between
arms of the interferometer. In all cases, our results are consistent with those
previously obtained by Caves using different mehods.

</DOC>
<DOC>
<DOCNO> 69588 </DOCNO>
D=4 N=1 Type IIB Orientifolds with Continuous Wilson Lines, Moving


  We investigate four-dimensional N=1 Type IIB orientifolds with continuous
Wilson lines, and their T-dual realizations as orientifolds with moving branes.
When continuous Wilson lines become discrete the gauge symmetry is enhanced and
the T-dual orientifold corresponds to branes sitting at the orbifold fixed
points. There is a field theoretic analog describing these phenomena as D- and
F-flat deformations of the T-dual model, where the branes sit at the origin
(original model without Wilson lines) as well as a deformation of the T-dual
model where sets of branes sit at the fixed points (the model with discrete
Wilson lines). We demonstrate these phenomena for the prototype Z_3
orientifold: we present an explicit construction of the general set of
continuous Wilson lines as well as their explicit field theoretic realization.

</DOC>
<DOC>
<DOCNO> 9174 </DOCNO>
Spectral properties and pseudogaps in a model with d-wave pairing


  A model with d-wave pairing symmetry is studied by employing a
non-perturbative sum rule approach. At low temperature the magnitude of a
normal state pseudogap shows strong $\vec{k}$ or angle dependence well fitted
by $\cos 2\phi$ form. With increasing temperature, the pseudogap closes at some
critical angle $\phi_{c}$ and beyond this angle a single quasiparticle-like
peak appears. The resulting Fermi surface is strongly temperature dependent.
Both in the spectral function and the density of states, the pseudogap
disappears in a manner that the spectral weight fills in the pseudogap instead
of closing it with increasing temperature. All these features are qualitatively
consistent with ARPES for underdoped cuprates.

</DOC>
<DOC>
<DOCNO> 101809 </DOCNO>
Stable mixing for cat maps and quasi-morphisms of the modular group


  It is well-known that the action of a hyperbolic element (``cat map'') of the
modular group on the 2-torus has strong chaotic dynamical properties such as
mixing and exponential decay of correlations. In this note we study stability
of this behaviour with respect to kicks. Our approach is based on geometric
group theory, and in particular on a new result on quasimorphisms of the
modular group.

</DOC>
<DOC>
<DOCNO> 84371 </DOCNO>
A quasilocal calculation of tidal heating


  We present a method for computing the flux of energy through a closed surface
containing a gravitating system. This method, which is based on the quasilocal
formalism of Brown and York, is illustrated by two applications: a calculation
of (i) the energy flux, via gravitational waves, through a surface near
infinity and (ii) the tidal heating in the local asymptotic frame of a body
interacting with an external tidal field. The second application represents the
first use of the quasilocal formalism to study a non-stationary spacetime and
shows how such methods can be used to study tidal effects in isolated
gravitating systems.

</DOC>
<DOC>
<DOCNO> 12555 </DOCNO>
On the Ginzburg-Landau Free Energy of Charge Density Waves with a


  The effective free energy of a charge density wave (CDW) with a
three-dimensional order is derived from a microscopic model (Fr\"olich model)
based on the path integral method. Electron hoping and Coulomb interaction
between chains are taken into account perturbatively, leading to an elastic
interchain coupling of the CDW ordered state.

</DOC>
<DOC>
<DOCNO> 39954 </DOCNO>
The process $e^+e^-\to\omega\pi^0\to\pi^0\pi^0\gamma$ up to 1.4 GeV


  The cross section of the $e^+e^-\to\omega\pi^0\to\pi^0\pi^0\gamma$ reaction
was measured by the SND detector at VEPP-2M $e^+e^-$ collider in the energy
range from threshold up to 1.4 GeV. Results of the cross section fitting by the
sum of $\rho$, $\rho^{\prime}$ and $\rho^{\prime\prime}$ contributions are
presented.

</DOC>
<DOC>
<DOCNO> 101153 </DOCNO>
Second order families of special Lagrangian 3-folds


  A second order family of special Lagrangian submanifolds of complex m-space
is a family characterized by the satisfaction of a set of pointwise conditions
on the second fundamental form. For example, the set of ruled special
Lagrangian submanifolds of complex 3-space is characterized by a single
algebraic equation on the second fundamental form.
  While the `generic' set of such conditions turns out to be incompatible,
i.e., there are no special Lagrangian submanifolds that satisfy them, there are
many interesting sets of conditions for which the corresponding family is
unexpectedly large. In some cases, these geometrically defined families can be
described explicitly, leading to new examples of special Lagrangian
submanifolds. In other cases, these conditions characterize already known
families in a new way. For example, the examples of Lawlor-Harvey constructed
for the solution of the angle conjecture and recently generalized by Joyce turn
out to be a natural and easily described second order family.

</DOC>
<DOC>
<DOCNO> 10721 </DOCNO>
Spin-Polarization transition in the two dimensional electron gas


  We present a numerical study of magnetic phases of the 2D electron gas near
freezing. The calculations are performed by diffusion Monte Carlo in the fixed
node approximation. At variance with the 3D case we find no evidence for the
stability of a partially polarized phase. With plane wave nodes in the trial
function, the polarization transition takes place at Rs=20, whereas the best
available estimates locate Wigner crystallization around Rs=35. Using an
improved nodal structure, featuring optimized backflow correlations, we confirm
the existence of a stability range for the polarized phase, although somewhat
shrunk, at densities achievable nowadays in 2 dimensional hole gases in
semiconductor heterostructures . The spin susceptibility of the unpolarized
phase at the magnetic transition is approximately 30 times the Pauli
susceptibility.

</DOC>
<DOC>
<DOCNO> 123203 </DOCNO>
Supermassive Black Holes from the SUNNS survey


  We report three new accurate mass measurements for the supermassive black
holes hosted by the early-type disk galaxies NGC2787, NGC4459 and NGC4596. The
targets were selected from a larger set of long-slit spectra obtained with the
Hubble Space Telescope as part of the Survey of Nearby Nuclei with STIS
(SUNNS). They display symmetric gas velocity curves that could be modeled as a
rotating disk in the joint potential of the stellar bulge and a putative
central black hole. They also show regular dust lane patterns that could be
used to infer the nuclear disk orientation. These three galaxies fall in the
black-hole mass vs. central stellar velocity dispersion plane in agreement with
the recently reported relation between these two quantities.

</DOC>
<DOC>
<DOCNO> 70190 </DOCNO>
Colour Dipoles and Saturation


  We employ values of the colour dipole cross section extracted from
electroproduction and photoproduction data to show that gluon saturation
effects are not required by the current HERA data but will become important in
the THERA energy region.

</DOC>
<DOC>
<DOCNO> 100220 </DOCNO>
Idempotent relations and generalized p-ranks of curves


  Let $Y $be a smooth projective irreducible curve defined over a finite field
$\mathbb{F}_{q}$. We assume that $G$ is a finite subgroup of the automorphism
group of $Y$ whose order divides $q-1$. We show that relations among
idempotents corresponding to the irreducible characters of subgroups $H$ of $G$
imply similar relations among generalized $p$-ranks of $Y$. We also relate this
result to the realization of finite groups as Galois groups of finite
unramified Galois covers of a curve over $\bar{\mathbb{F}}_{q}$.

</DOC>
<DOC>
<DOCNO> 119327 </DOCNO>
Evolutionary models for very-low-mass stars and brown dwarfs with dusty


  We present evolutionary calculations for very-low-mass stars and brown dwarfs
based on synthetic spectra and non-grey atmosphere models which include dust
formation and opacity, i.e. objects with $\te\simle 2800$ K. The interior of
the most massive brown dwarfs is shown to develop a conductive core after $\sim
2$ Gyr which slows down their cooling. Comparison is made in optical and
infrared color-magnitude diagrams with recent late-M and L-dwarf observations.
The saturation in optical colors and the very red near-infrared colors of these
objects are well explained by the onset of dust formation in the atmosphere.
Comparison of the faintest presently observed L-dwarfs with these dusty
evolutionary models suggests that dynamical processes such as turbulent
diffusion and gravitational settling are taking place near the photosphere. As
the effective temperature decreases below $\te\approx 1300-1400$ K, the colors
of these objects move to very blue near-infrared colors, a consequence of the
ongoing methane absorption in the infrared. We suggest the possibility ofa
brown dwarf dearth in $J,H,K$ color-magnitude diagrams around this temperature.

</DOC>
<DOC>
<DOCNO> 102068 </DOCNO>
Stasheff structures and differentials of the Adams spectral sequence


  The Adams spectral sequence was invented by J.F.Adams almost fifty years ago
for calculations of stable homotopy groups of topological spaces and in
particular of spheres. The calculation of differentials of this spectral
sequence is one of the most difficult problem of Algebraic Topology. Here we
consider an approach to solve this problem in the case of Z/2 coefficients and
find inductive formulas for the differentials. It is based on the Stasheff
algebra structures, operad methods and functional homology operations.

</DOC>
<DOC>
<DOCNO> 122142 </DOCNO>
Further detections of OH masers in carbon stars with silicate features


  A sample of J-type carbon stars was searched for OH maser emission. The new
detection of three OH lines towards two silicate carbon stars is reported. In
V778 Cyg, previously known as the main-lines (1665 and 1667 MHz) maser source,
the satellite 1612 MHz emission was discovered while in NSV 2814 the main OH
lines were detected. The presence of OH maser lines confirms the former
suggestion that oxygen-rich material is located in the vicinity ($\approx$
$10^{15-16}$ cm) of silicate carbon stars.

</DOC>
<DOC>
<DOCNO> 123295 </DOCNO>
Galactic chemical abundance evolution in the solar neighborhood up to


  We have developed a detailed standard chemical evolution model to study the
evolution of all the chemical elements up to the iron peak in the solar
vicinity. We consider that the Galaxy was formed through two episodes of
exponentially decreasing infall, out of extragalactic gas. In a first infall
episode, with a duration of $\sim$ 1 Gyr, the halo and the thick disk were
assembled out of primordial gas, while the thin disk formed in a second episode
of infall of slightly enriched extragalactic gas, with much longer timescale.
The model nicely reproduces the main observational constraints of the solar
neighborhood, and the calculated elemental abundances at the time of the solar
birth are in excellent agreement with the solar abundances. By the inclusion of
metallicity dependent yields for the whole range of stellar masses we follow
the evolution of 76 isotopes of all the chemical elements between hydrogen and
zinc. Those results are confronted with a large and recent body of
observational data, and we discuss in detail the implications for stellar
nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 67791 </DOCNO>
Stabilizing Textures in 3+1 Dimensions with Semilocality


  It is shown that textures in 3+1 dimensions can be stabilized by partial
gauging (semilocality) of the vacuum manifold such that topological unwinding
by a gauge transformation is not possible. This introduction of gauge fields
can be used to evade Derrick's theorem without higher powers of derivatives and
prevent the usual collapse of textures by the effective `pressure' terms
induced by the gauge fields. A virial theorem is derived and shown to be a
manifestation of the stability of the configuration towards collapse.

</DOC>
<DOC>
<DOCNO> 40081 </DOCNO>
Study of B Decays to Charmonium States $B\to \eta_{c}K$ and $B\to


  In a sample of $9.66\times 10^6 B\bar{B}$ pairs collected with the CLEO
detector we make the first observation of B decays to an $\eta_c$ and a kaon.
We measure branching fractions $BR(B^+\to\eta_c K^+) = (0.69 + 0.26 - 0.21 +-
0.08 +- 0.20)\times 10^{-3}$ and $BR(B^0\to\eta_c K^0) = (1.09 + 0.55 - 0.42 +-
0.12 +- 0.31)\times 10^{-3}$, where the first error is statistical, the second
is systematic and the third is from the $\eta_c$ branching fraction
uncertainty. From these we extract the $\eta_c$ decay constant in the
factorization approximation, $f_{\eta_c} = 335 +- 75$ MeV. We also search for B
decays to a $\chi_{c0}$ and a kaon. No evidence for a signal is found and we
set 90% CL upper limits: $BR(B^+\to\chi_{c0} K^+) < 4.8\times 10^{-4}$ and
$BR(B^0\to\chi_{c0} K^0) < 5.0\times 10^{-4}$.

</DOC>
<DOC>
<DOCNO> 150509 </DOCNO>
OPEs and 4-point Functions in AdS/CFT Correspondence


  Recently D'Hoker et al. (1999) computed 4-point correlation functions of
axion and dilaton fields in type IIB SUGRA on AdS_5 x S^5. We reproduce from a
CFT point of view all power law singular terms in these AdS 4-point amplitudes.
We also calculate a corresponding 4-point function in the weak coupling limit,
g_{YM}^2 N -> 0. Comparison reveals the existence of a primary operator that
contributes to these same singular terms in the weak coupling limit but which
does not contribute to the power law singular terms of the type IIB SUGRA
4-point function. We conclude that this new operator is not a chiral primary
and hence acquires a large anomalous dimension in the strong coupling regime.

</DOC>
<DOC>
<DOCNO> 11017 </DOCNO>
Pairing, Stripes, Lattice Distortions and Superconductivity in Cuprate


  We propose a model for a spatially modulated collective state of
superconducting cuprates in which the electronic properties vary locally in
space. In this model the regions of higher hole density (called stripes) are
described as Luttinger liquids and the regions of lower density
(antiferromagnetic ladders) as an interacting bosonic gas of d$_{x^2-y^2}$ hole
pairs. We show that the transition to the superconducting state is topological
and driven by decay processes among these elementary excitations in the
presence of vibrations.

</DOC>
<DOC>
<DOCNO> 100041 </DOCNO>
Life and work of the mathemagician Srinivasa Ramanujan


  The Life of Srinivasa Ramanujan (1887 - 1920), the renowned Indian
Mathematician, is presented, in this the first of a series of lectures,
delivered at the Indian Institute for Advanced Study, Shimla.

</DOC>
<DOC>
<DOCNO> 101209 </DOCNO>
Representations of hermitian kernels by means of Krein spaces II.


  In this paper we study hermitian kernels invariant under the action of a
semigroup with involution. We characterize those hermitian kernels which
realize the given action by bounded operators on a Krein space. Applications to
the GNS representation of *-algebras associated to hermitian functionals are
given. We explain the key role played by the Kolmogorov decomposition in the
construction of Weyl exponentials associated to an indefinite inner product and
in the dilation thoery of hermitian maps on C*-algebras.

</DOC>
<DOC>
<DOCNO> 80727 </DOCNO>
The finite temperature QCD phase transition with domain wall fermions


  The domain wall formulation of lattice fermions is expected to support
accurate chiral symmetry, even at finite lattice spacing. Here we attempt to
use this new fermion formulation to simulate two-flavor, finite temperature QCD
near the chiral phase transition. In this initial study, a variety of quark
masses, domain wall heights and domain wall separations are explored using an
8^3 x 4 lattice. Both the expectation value of the Wilson line and the chiral
condensate show the temperature dependence expected for the QCD phase
transition. Further, the desired chiral properties are seen for the chiral
condensate, suggesting that the domain wall fermion formulation may be an
effective approach for the numerical study of QCD at finite temperature.

</DOC>
<DOC>
<DOCNO> 12926 </DOCNO>
Excitons and charged excitons in semiconductor quantum wells


  A variational calculation of the ground-state energy of neutral excitons and
of positively and negatively charged excitons (trions) confined in a
single-quantum well is presented. We study the dependence of the correlation
energy and of the binding energy on the well width and on the hole mass. The
conditional probability distribution for positively and negatively charged
excitons is obtained, providing information on the correlation and the charge
distribution in the system. A comparison is made with available experimental
data on trion binding energies in GaAs-, ZnSe-, and CdTe-based quantum well
structures, which indicates that trions become localized with decreasing
quantum well width.

</DOC>
<DOC>
<DOCNO> 84607 </DOCNO>
Large "Dipolar" Vacuum Fluctuations in Quantum Gravity


  We study a novel set of gravitational field configurations, called "dipolar
zero modes", which give an exactly null contribution to the Einstein action and
are thus candidates to become large fluctuations in the quantized theory. They
are generated by static unphysical sources satisfying (up to terms of order
G^2) the simple condition Int d^3x T_00(x) = 0. We give two explicit examples
of virtual sources: (i) a "mass dipole" consisting of two separated mass
distributions with different signs; (ii) two concentric "+/- shells". The field
fluctuations can be large even at macroscopic scale. There are some, for
instance, which last ~ 1 s or more and correspond to the field generated by a
virtual source with size ~ 1 cm and mass ~ 10^6 g. This appears paradoxical,
for several reasons, both theoretical and phenomenological. We also give an
estimate of possible suppression effects following the addition to the pure
Einstein action of cosmological or R^2 terms.

</DOC>
<DOC>
<DOCNO> 102437 </DOCNO>
Two-dimensional dynamical systems admitting the normal shift


  Two-dimensional case in the theory of dynamical systems admitting the normal
shift differs crucially from multidimensional case. Features of two-dimensional
case are gathered and studied in this thesis.

</DOC>
<DOC>
<DOCNO> 118461 </DOCNO>
Electron energy losses near pulsar polar caps: a Monte Carlo approach


  We use Monte Carlo approach to study the energetics of electrons accelerated
in a pulsar polar gap. As energy-loss mechanisms we consider magnetic Compton
scattering of thermal X-ray photons and curvature radiation. The results are
compared with previous calculations which assumed that changes of electron
energy occurred smoothly according to approximations for the average energy
loss rate due to the Compton scattering. We confirm a general dependence of
efficiency of electron energy losses due to inverse Compton mechanism on the
temperature and size of a thermal polar cap and on the pulsar magnetic field.
However, we show that trajectories of electrons in energy-altitude space as
calculated in the smooth way do not always coincide with averaged Monte Carlo
behaviour. In particular, for pulsars with high magnetic field strength
($B_{pc} > 3\times 10^{12}$ G) and low thermal polar cap temperatures ($T <
5\times 10^6$ K) final electron Lorentz factors computed with the two methods
may differ by a few orders of magnitude. We discuss consequences for particular
objects with identified thermal X-ray spectral components like Geminga, Vela,
and PSR B1055-52.

</DOC>
<DOC>
<DOCNO> 10070 </DOCNO>
Fluctuation-Facilitated Charge Migration along DNA


  We propose a model Hamiltonian for charge transfer along the DNA double helix
with temperature driven fluctuations in the base pair positions acting as the
rate limiting factor for charge transfer between neighboring base pairs. We
compare the predictions of the model with the recent work of J.K. Barton and
A.H. Zewail (Proc.Natl.Acad.Sci.USA, {\bf 96}, 6014 (1999)) on the unusual
two-stage charge transfer of DNA.

</DOC>
<DOC>
<DOCNO> 100857 </DOCNO>
H-bubbles through a point


  We prove existence of S^2-type parametric surfaces in R^3 having prescribed
noncostant mean curvature and passing through a given point in R^3.

</DOC>
<DOC>
<DOCNO> 70628 </DOCNO>
Constraints on R-parity Violation from Precision Electroweak


  We constrain the size of R-parity violating couplings using precision
electroweak data.

</DOC>
<DOC>
<DOCNO> 12675 </DOCNO>
Hydrodynamic Equation for the Breakdown of the Quantum Hall Effect in a


  The hydrodynamic equation for the spatial and temporal evolution of the
electron temperature T_e in the breakdown of the quantum Hall effect at
even-integer filling factors in a uniform current density j is derived from the
Boltzmann-type equation, which takes into account electron-electron and
electron-phonon scatterings. The derived equation has a drift term, which is
proportional to j and to the first spatial derivative of T_e. Applied to the
spatial evolution of T_e in a sample with an abrupt change of the width along
the current direction, the equation gives a distinct dependence on the current
direction as well as a critical relaxation, in agreement with the recent
experiments.

</DOC>
<DOC>
<DOCNO> 84616 </DOCNO>
Wave propagation in linear electrodynamics


  The Fresnel equation governing the propagation of electromagnetic waves for
the most general linear constitutive law is derived. The wave normals are found
to lie, in general, on a fourth order surface. When the constitutive
coefficients satisfy the so-called reciprocity or closure relation, one can
define a duality operator on the space of the two-forms. We prove that the
closure relation is a sufficient condition for the reduction of the fourth
order surface to the familiar second order light cone structure. We finally
study whether this condition is also necessary.

</DOC>
<DOC>
<DOCNO> 70378 </DOCNO>
A full one-loop charge symmetry breaking effective potential


  We calculate the one-loop contributions to the effective potential for the
minimal supersymmetric model when scalar fields other than the Higgses have
vacuum expectation values. The importance of these contributions for studies of
charge and colour breaking bounds is discussed.

</DOC>
<DOC>
<DOCNO> 116815 </DOCNO>
Negative Group Velocity


  The group velocity for pulses in an optical medium can be negative at
frequencies between those of a pair of laser-pumped spectral lines. The gain
medium then can amplify the leading edge of a pulse resulting in a time advance
of the pulse when it exits the medium, as has been recently demonstrated in the
laboratory. This effect has been called superluminal, but, as a classical
analysis shows, it cannot result in signal propgation at speeds greater than
that of light in vacuum.

</DOC>
<DOC>
<DOCNO> 9669 </DOCNO>
Bose-Einstein condensation in inhomogeneous Josephson arrays


  We show that spatial Bose-Einstein condensation of non-interacting bosons
occurs in dimension d < 2 over discrete structures with inhomogeneous topology
and with no need of external confining potentials. Josephson junction arrays
provide a physical realization of this mechanism. The topological origin of the
phenomenon may open the way to the engineering of quantum devices based on
Bose-Einstein condensation. The comb array, which embodies all the relevant
features of this effect, is studied in detail.

</DOC>
<DOC>
<DOCNO> 69853 </DOCNO>
Resolution of a long standing discrepancy in R with spin zero quarks


  A previously successful dispersive method has been applied to understand
different values for $R(\sqrt{s} = 5 \div 7.5 GeV)$ obtained by MARK I and
Crystal Ball collaborations. We compute $R$ in the disputed region with data
from outside this region and asymptotic behavior given by the standard model
with 5 quark flavors, and find agreement with the Crystal Ball result. On the
other hand, the MARK I data are reproduced if we augment the asymptotic
behavior with contributions from a single spin zero quark of charge ($ -1/3$).
The visible hadronic fragments from such scalar quarks are not likely to
produce predominantly pure 2-jet events at such low energies. Hence, such decay
modes may have been removed by the Crystal Ball energy imbalance cuts in their
definition of hadronic events but not in MARK I events, thus accounting for the
discrepancy in the two results. Upper bounds on spin zero quark production at
LEP through $Z$ decay data are used to estimate the mixing angle between $T_3\
= -1/2$ and $T_3 = 0$ scalar quarks. Recent negative results about spin zero
quarks from CLEO are critically examined. We briefly discuss diquark production
hypothesis and find it very unlikely to explain the discrepancy.

</DOC>
<DOC>
<DOCNO> 121774 </DOCNO>
Identification of the companion stars of Type Ia supernovae


  The nature of the binary systems giving rise to Type Ia supernovae (SNeIa)
remains an unsolved problem. In this {\it Letter} we calculate, from the
statistics of initial conditions (masses and binary separations), the mass,
luminosity, and velocity distributions of the possible binary companions
(main-sequence star, subgiant, red giant) following the explosion of the white
dwarf which gives rise to the SNeIa. Those companions could be detected from
either their proper or their radial motions, by means of high-precision
astrometric and radial-velocity measurements in young, nearby supernova
remnants. Peculiar velocities typically ranging from 100 to 450 km s$^{-1}$
should be expected, which places proper-motion measurements within reach of HST
instruments and makes radial-velocity ones feasible with 2.5-4m class
telescopes from the ground. Detections would solve the long-standing problem of
which kind of binaries do produce SNeIa and clear up the way to accurate
physical modeling of the explosions.

</DOC>
<DOC>
<DOCNO> 69145 </DOCNO>
Probing the Structure of Nucleons in the Resonance Region


  Status, open questions, and future prospects of the physics of excited
nucleons are discussed. Emphasis is on the study of the structure of nucleons
via measurements of their electromagnetic transition form factors, the search
for "missing" resonances, the spin structure of the nucleon in the resonance
region, and connections between the resonance and the deep-inelastic regimes.

</DOC>
<DOC>
<DOCNO> 117893 </DOCNO>
Study of Multi-muon Events from EAS with the L3 Detector at Shallow


  We present first preliminary data from the L3+Cosmics experiment and results
from Monte Carlo simulations of multi-muon events as observed 30 m underground.

</DOC>
<DOC>
<DOCNO> 117203 </DOCNO>
Number counts against K-corrections


  Having based on the analysis of Pietronero and collaborators the galaxy
number counts can be considered as an evidence of that the geometry of the
universe is euclidean and that the K-corrections are absent. In such a universe
measuring the cosmological redshift of the object and measuring the flux from
the object are inconsistent. It is considered the model of the universe which
describes the above properties.

</DOC>
<DOC>
<DOCNO> 68411 </DOCNO>
Virtual Color Superconductivity and Nucleon Structure


  The observed electromagnetic (EM) properties of a nucleon at high energy are
studied to search for a possible metastable color superconducting phase, called
a virtual phase, that has an energy density close to the true ground state of
the vacuum. The discussion is based on a mechanism of spontaneous partial
breaking of the EM U(1) gauge symmetry inside a color superconductor. Favorable
evidences for such a scenario are found.

</DOC>
<DOC>
<DOCNO> 152431 </DOCNO>
Constraints on the tachyon condensate from anomalous symmetries


  Using anomalous symmetries of the cubic string field theory vertex we derive
set of relations between the coefficients of the tachyon condensate. They are
in agreement with the results obtained from level truncation approximation.

</DOC>
<DOC>
<DOCNO> 100712 </DOCNO>
On integrability of infinitesimal actions


  We use foliations and connections on principal Lie groupoid bundles to prove
various integrability results for Lie algebroids. In particular, we show, under
quite general assumptions, that the semi-direct product associated to an
infinitesimal action of one integrable Lie algebroid on another is integrable.
This generalizes recent results of Dazord and Nistor.

</DOC>
<DOC>
<DOCNO> 85374 </DOCNO>
General exact solution of the Einstein-Dirac equations with the


  The general exact solution of the Einstein-Dirac equations with cosmological
constant in the homogeneous Riemannian space of the Bianchi 1 type is obtained.

</DOC>
<DOC>
<DOCNO> 151762 </DOCNO>
$CP^{1}$ model with Hopf interaction: the quantum theory


  The $CP^1$ model with Hopf interaction is quantised following the
Batalin-Tyutin (BT) prescription. In this scheme, extra BT fields are
introduced which allow for the existence of only commuting first-class
constraints. Explicit expression for the quantum correction to the expectation
value of the energy density and angular momentum in the physical sector of this
model is derived. The result shows, in the particular operator ordering that we
have chosen to work with, that the quantum effect has a divergent contribution
of $ {\cal O} (\hbar^2)$ in the energy expectation value. But, interestingly
the Hopf term, though topological in nature, can have a finite ${\cal O}
(\hbar)$ contribution to energy density in the homotopically nontrivial
topological sector. The angular momentum operator, however, is found to have no
quantum correction, indicating the absence of any fractional spin even at this
quantum level. Finally, the extended Lagrangian incorporating the BT auxiliary
fields is computed in the conventional framework of BRST formalism exploiting
Faddeev-Popov technique of path integral method.

</DOC>
<DOC>
<DOCNO> 122357 </DOCNO>
A New Approach to Mass Measurements of UHECR: Horizontal Air Showers


  The role of Horizontal Showers induced by cosmic rays is discussed in detail.
A new approach to the calculation of the muon component in horizontal air
showers induced by protons, heavier nuclei or photons is presented which allows
a simple analytical evaluation of the muon density profiles at ground level.
The results of the first application of these results to horizontal air showers
detected at the Haverah Park Array by the recently started {\sl Leeds-Santiago
collaboration}, leading to important restrictions on composition at ultra high
energies, are reported.

</DOC>
<DOC>
<DOCNO> 178468 </DOCNO>
Giant monopole resonance and nuclear compression modulus for 40Ca and


  Using a collective potential derived on the basis of the Generator Coordinate
Method with Skyrme interactions we obtain values for the compression modulus of
40Ca which are in good agreement with a recently obtained experimental value.
Calculated values for the compression modulus for 16O are also given. The
procedure involved in the derivation of the collective potential is briefly
reviewed and discussed.

</DOC>
<DOC>
<DOCNO> 122386 </DOCNO>
Particle modeling of disk-shaped galaxies of stars on nowadays


  The time evolution of initially balanced, rapidly rotating models for an
isolated disk of highly flattened galaxies of stars is calculated. The method
of direct integration of the Newtonian equations of motion of stars over a time
span of many galactic rotations is applied. Use of modern concurrent
supercomputers has enabled us to make long simulation runs using a sufficiently
large number of particles N=30,000. One of the goals of the present simulation
is to test the validities of a modified local criterion for stability of
Jeans-type gravity perturbations (e.g. those produced by a barlike structure, a
spontaneous perturbation and/or a companion galaxy) in a self-gravitating,
infinitesimally thin and collisionless disk. In addition to the local criterion
we are interested in how model particles diffuse in velocity. This is of
considerable interest in the kinetic theory of stellar disks. Certain
astronomical implications of the simulations to actual disk-shaped (i.e.
rapidly rotating) galaxies are explored. The weakly nonlinear, or quasi-linear
kinetic theory of the Jeans instability in disk galaxies of stars is described
as well.

</DOC>
<DOC>
<DOCNO> 116975 </DOCNO>
Multiple-Charge Beam Dynamics in an Ion Linac


  There is demand for the construction of a medium-energy ion linear
accelerator based on superconducting rf (SRF) technology. It must be capable of
producing several hundred kilowatts of CW beams ranging from protons to
uranium. A considerable amount of power is required in order to generate
intense beams of rare isotopes for subsequent acceleration. At present,
however, the beam power available for the heavier ions would be limited by ion
source performance. To overcome this limit, we have studied the possibility of
accelerating multiple-charge-state (multi-Q) beams through a linac. We show
that such operation is made feasible by the large transverse and longitudinal
acceptance which can be obtained in a linac using superconducting cavities.
Multi-Q operation provides not only a substantial increase in beam current, but
also enables the use of two strippers, thus reducing the size of linac
required. Since the superconducting (SC) linac operates in CW mode, space
charge effects are essentially eliminated except in the ECR/RFQ region.
Therefore an effective emittance growth due to the multi-charge beam
acceleration can be minimized.

</DOC>
<DOC>
<DOCNO> 10312 </DOCNO>
Conductance peak motion due to a magnetic field in weakly coupled


  We study the influence of moderate exchange interactions of electrons on the
behavior of the peaks in the conductance of single electron transistors. We
numerically reproduce recently observed features of both the peak positions and
the peak heights magnetic field dependence. These features unambiguously
identify the total spin $S$ of each ground state. We evaluate the probability
of each $S$ (combination of spontaneous and induced magnetization) as a
function of the exchange strength, $J$, and external magnetic field, $B$. The
expressions involve only $J$ and $g$-factor as adjustable parameters. Moreover,
in a surprisingly broad parameter range these probabilities are determined by
certain linear combinations of $J$ and $B$.

</DOC>
<DOC>
<DOCNO> 67759 </DOCNO>
Of Dips, Structures and Eikonalization


  We have investigated several models of Pomeron and Odderon contributions to
high energy elastic $pp$ and $\bar p p$ scattering. The questions we address
concern their role in this field, the behavior of the scattering amplitude (or
of the total cross-section) at high energy, and how to fit all high energy
elastic data. The data are extremely well reproduced by our approach at all
momenta and for sufficiently high energies. The relative virtues of Born
amplitudes and of different kinds of eikonalizations are considered. An
important point in this respect is that secondary structures are predicted in
the differential cross-sections at increasing energies and these phenomena
appear quite directly related to the procedure of eikonalizing the various Born
amplitudes. We conclude that these secondary structures arise naturally within
the eikonalized procedure (although their precise localization turns out to be
model dependent). The fitting procedure naturally predicts the appearance of a
zero at small $|t|$ in the real part of the even amplitude as anticipated by
general theorems. We would like to stress, once again, how important it would
be to have at LHC both $pp$ and $p \bar p$ options for many questions connected
to the general properties of high energy hadronic physics and for a check of
our predictions.

</DOC>
<DOC>
<DOCNO> 71543 </DOCNO>
From Anisotropy to Omega


  Following the recent measurement of the acoustic peak by the BOOMERanG and
MAXIMA experiments in the CMB anisotropy angular power spectrum, many analyses
have found that the geometry of the Universe is very close to flat, but
slightly closed models are favoured. In this paper we will briefly review how
the CMB anisotropies depend on the curvature, explaining any assumptions we
could make and showing that this skewness towards closed models can be easily
explained by degeneracies in the cosmological parameters. While it is difficult
to give independent constraints on the cosmological constant and/or different
forms of dark energies, we will also show that combining CMB measurements with
other observational data will introduce new and tighter constraints, like
$\Omega_\Lambda > 0$ at high significance.

</DOC>
<DOC>
<DOCNO> 101862 </DOCNO>
Rank frequencies for quadratic twists of elliptic curves


  We give explicit examples of infinite families of elliptic curves E over Q
with (nonconstant) quadratic twists over Q(t) of rank at least 2 and 3. We
recover some results announced by Mestre, as well as some additional families.
Suppose D is a squarefree integer and let r_E(D) denote the rank of the
quadratic twist of E by D. We apply results of Stewart and Top to our examples
to obtain results of the form #{D : |D| < x, r_E(D) >= 2} >> x^{1/3}, #{D : |D|
< x, r_E(D) >= 3} >> x^{1/6} for all sufficiently large x.

</DOC>
<DOC>
<DOCNO> 83504 </DOCNO>
A Virtual Java Simulation Lab for Computer Science Students


  The VJ-Lab is a project oriented to improve the students learning process of
Computer Science degree at the National University of La Plata. The VJ-Lab is a
Web application with Java based simulations. Java can be used to provide
simulation environments with simple pictorial interfaces that can help students
to understand the subject. There are many fields in which it is difficult to
give students a feel for the subject that they are learning. Computer based
simulations offer a fun and effective way to enable students to learn by doing.
Both, practicing skills and applying knowledge are both allowed in simulated
worlds. We will focus on the VJ-Lab project overview, the work in progress and
some Java based simulations running. They imitate the behavior of data network
protocol and data structure algorithms. These applets are produced by the
students of the 'Software Development Laboratory' course.

</DOC>
<DOC>
<DOCNO> 10895 </DOCNO>
Statistics of stable marriages


  In the stable marriage problem N men and N women have to be matched by pairs
under the constraint that the resulting matching is stable. We study the
statistical properties of stable matchings in the large N limit using both
numerical and analytical methods. Generalizations of the model including
singles and unequal numbers of men and women are also investigated.

</DOC>
<DOC>
<DOCNO> 122406 </DOCNO>
The Stellar IMF from Turbulent Fragmentation


  The morphology and kinematics of molecular clouds (MCs) are best explained as
the consequence of super-sonic turbulence. Super-sonic turbulence fragments MCs
into dense sheets, filaments and cores and large low density ``voids'', via the
action of highly radiative shocks. We refer to this process as turbulent
fragmentation.
  In this work we derive the mass distribution of dense cores due to turbulent
fragmentation. The distribution of core masses depends primarily on the power
spectrum of the turbulent flow and on the jump conditions for isothermal shocks
in a magnetized gas. For a power spectrum index beta=-1.8, consistent with
results of numerical experiments of super-sonic turbulence as well as with
Larson's velocity-size relation, we obtain a power law mass distribution of
dense cores with a slope equal to 3/(4-beta)=1.36, consistent with the slope of
the stellar IMF. Given the fact that turbulent fragmentation is unavoidable in
super-sonic turbulence, and given the success of the present model in
predicting the correct slope of the stellar IMF without any free parameter, we
conclude that turbulent fragmentation is the most important process at the
origin of the stellar IMF.
  If the magnetic field is so weak that the magnetic pressure in the postshock
gas is smaller than the thermal pressure the IMF is much steeper, with a power
law slope 3/(5-2*beta)=2.1, which may be relevant for star formation at high
redshift.

</DOC>
<DOC>
<DOCNO> 8837 </DOCNO>
Renormalization group study of the 1d polaron problem


  We investigate the one-dimensional polaron problem and calculate the ground
state energy and the effective mass. We use a real-time renormalization group
method and compare our results with first and second order perturbation theory,
with Feynman's variational principle and with the method of Lee, Low and Pines.

</DOC>
<DOC>
<DOCNO> 123257 </DOCNO>
Dust Migration and Morphology in Optically Thin Circumstellar Gas Disks


  We analyze the dynamics of gas-dust coupling in the presence of stellar
radiation pressure in circumstellar gas disks, which are in a transitional
stage between the gas-dominated, optically thick, primordial nebulae, and the
dust-dominated, optically thin Vega-type disks. Dust undergo radial migration,
seeking a stable equilibrium orbit in corotation with gas. The migration of
dust gives rise to radial fractionation of dust and creates a variety of
possible observed disk morphologies, which we compute by considering the
equilibrium between the dust production and the dust-dust collisions removing
particles from their equilibrium orbits. Sand-sized and larger grains are
distributed throughout most of the gas disk, with concentration near the gas
pressure maximum in the inner disk. Smaller grains (typically in the range of
10 to 200 micron) concentrate in a prominent ring structure in the outer region
of the gas disk (presumably at radius 100 AU), where gas density is rapidly
declining with radius. The width and density, as well as density contrast of
the dust ring with respect to the inner dust disk depend on the distribution of
gas. Our results open the prospect for deducing the distribution of gas in
circumstellar disks by observing their dust. We have qualitatively compared our
models with two observed transitional disks around HR 4796A and HD 141569A.
Dust migration can result in observation of a ring or a bimodal radial dust
distribution, possibly very similar to the ones produced by gap-opening
planet(s) embedded in the disk, or shepherding it from inside or outside. We
conclude that a convincing planet detection via dust imaging should include
specific non-axisymmetric structure following from the dynamical simulations of
perturbed disks.

</DOC>
<DOC>
<DOCNO> 84675 </DOCNO>
A Comment on Non-Archimedean Character of Quantum Buoyancy


  In a gedankenexperiment about the generalized second law (GSL) of black hole
thermodynamics, the buoyant force by black hole atmosphere (the acceleration
radiation) plays an important role, and then it is significant to understand
the nature of the buoyant force.
  Recently, Bekenstein criticizes that the fluid approximation of the
acceleration radiation which is often used in the estimation of the buoyant
force is invalid for the case that the size of the target is much less than a
typical wavelength of the acceleration radiation, due to the diffractive effect
of wave scattering.
  In this letter, we argue that even if it is correct that we should calculate
the buoyant force as a wave scattering process, its implication in the GSL
strongly depends on whether there exists any massless scalar field, that is,
S-wave scattering. By reconsidering the diffractive effect by S-wave
scattering, we show that if some massless scalar field exists, then the GSL can
hold without invoking a new physics, such as an entropy bound for matter.

</DOC>
<DOC>
<DOCNO> 117512 </DOCNO>
An Instability-driven Dynamo for Gamma Ray Bursts


  We show that an MHD-instability driven dynamo (IDD) operating in a hot
accretion disk is capable of generating energetically adequate magnetic flux
deposition rates above and below a mildly advective accretion disk structure.
  The dynamo is driven by the magnetorotational instability (MRI) of a toroidal
field in a shear flow and is limited by the buoyancy of `horizontal' flux and
by reconnection in the turbulent medium. The efficiency of magnetic energy
deposition is estimated to be comparable to the neutrino losses although an MHD
collimation mechanism may deem this process a more viable alternative to
neutrino-burst-driven models of gamma ray bursts.

</DOC>
<DOC>
<DOCNO> 119265 </DOCNO>
Lopsidedness in dwarf irregular galaxies


  We quantify the amplitude of the lopsidedness, the azimuthal angular
asymmetry index, and the concentration of star forming regions, as represented
by the distribution of the H$\alpha$ emission, in a sample of 78 late-type
irregular galaxies. We bin the observed galaxies in two groups representing
blue compact galaxies (BCDs) and low surface brightness dwarf galaxies (LSBs).
The light distribution is analysed with a novel algorithm, which allows
detection of details in the light distribution pattern.
 We find that while the asymmetry of the underlying continuum light,
representing the older stellar generations, is relatively small, the H$\alpha$
emission is very asymmetric and is correlated in position angle with the
continuum light.
 We test a model of random star formation over the extent of a galaxy by
simulating HII regions in artificial dwarf galaxies. The implication is that
random star formation over the full extent of a galaxy may be generated in LSB
dwarf-irregular galaxies but not in BCD galaxies.

</DOC>
<DOC>
<DOCNO> 40299 </DOCNO>
Search for the Decay Kl -> pi0 e+ e-


  We report on a search for the decay Kl -> pi0 e+ e- carried out by the
KTeV/E799 experiment at Fermilab. This decay is expected to have a significant
CP violating contribution and the measurement of its branching ratio could
support the CKM mechanism for CP violation or could point to new physics. Two
events were observed in the 1997 data with an expected background of 1.06
+-0.41 events, and we set an upper limit Br(Kl -> pi0 e+ e-) < 5.1 x 10^-10 at
the 90% confidence level.

</DOC>
<DOC>
<DOCNO> 14133 </DOCNO>
Effect of Screening of Intermicellar Interactions on the Linear and


  We report our studies of the linear and nonlinear rheology of aqueous
solutions of the surfactant cetyl trimethylammonium tosylate (CTAT) with
varying amounts of sodium chloride (NaCl). The CTAT concentration is fixed at
42mM and the salt concentration is varied between 0mM to 120mM. On increasing
the salt (NaCl) concentration, we see three distinct regimes in the zero-shear
viscosity and the high frequency plateau modulus data. In regime I, the
zero-shear viscosity shows a weak increase with salt concentration due to
enhanced micellar growth. The decrease in the zero-shear viscosities with salt
concentration in regimes I I and III can be explained in terms of
inter-micellar branching. The most intriguing feature of our data however, is
the anomalous behavior of the high frequency plateau modulus in regime II (0.12
$\le \frac{[NaCl]}{[CTAT]} \le$ 1. 42). In this regime, the plateau modulus
{\it increases} with an increase in NaCl concentration. This is highly
counter-intuitive, since the correlation length of concentration fluctuations
and hence the plateau modulus $G_{\circ}$ are not expected to change
appreciably in the semi-dilute regime. We propose to explain the changes in
regime II in terms of the unbinding of the organic counterions (tosylate) from
the CTA$^{+}$ surfaces on the addition of NaCl. In the nonlinear flow curves of
the samples with high salt content, significant deviations from the predictions
of the Giesekus model for entangled micelles are observed.

</DOC>
<DOC>
<DOCNO> 99680 </DOCNO>
Cyclic Cohomology and Hopf Symmetry


  Cyclic cohomology has been recently adapted to the treatment of Hopf symmetry
in noncommutative geometry. The resulting theory of characteristic classes for
Hopf algebras and their actions on algebras allows to expand the range of
applications of cyclic cohomology. It is the goal of the present paper to
illustrate these recent developments, with special emphasis on the application
to transverse index theory, and point towards future directions. In particular,
we highlight the remarkable accord between our framework for cyclic cohomology
of Hopf algebras on one hand and both the algebraic as well as the analytic
theory of quantum groups on the other, manifest in the construction of the
modular square.

</DOC>
<DOC>
<DOCNO> 7683 </DOCNO>
Field Dependent Specific-Heat of Rare Earth Manganites


  The low temperature specific heat C(H) of several rare-earth manganites
(La_(0.7)Sr_(0.3)MnO_(3), Nd_(0.5)Sr_(0.5)MnO_(3), Pr_(0.5)Sr_(0.5)MnO_(3),
La_(0.67)Ca_(0.33)MnO$_(3), La_(0.5)Ca_(0.5)MnO_(3), La_(0.45)Ca_(0.55)MnO_(3)
and La_(0.33)Ca_(0.67)MnO_(3)) was measured as a function of magnetic field. We
observed behaviour consistent with thermodynamic expectations, i.e., C(H)
decreases with field for ferromagnetic metallic compounds by an amount which is
in quantitative agreement with spin wave theory. We also find that C(H)
increases with field in most compounds with a charge-ordered antiferromagnetic
ground state. In compounds which show evidence of a coexistence of
ferromagnetic metallic and antiferromagnetic charge-ordered states, C(H)
displays some unusual non-equilibrium effects presumably associated with the
phase-separation of the two states. We also observe a large anomalous low
temperature specific heat at the doping induced metal-insulator transition (at
x = 0.50) in La_(1-x)Ca_(x)MnO_(3).

</DOC>
<DOC>
<DOCNO> 152197 </DOCNO>
Relativistically covariant formulation of the canonical theory of


  An explicit Lorentz covariant formulation of the canonical theory for
classical fields is established on a space-like hypersurface. Hamilton's
equations and a Poisson bracket are defined on the space-like hypersurface. The
Poisson bracket relations between total momentum and total angular momentum
satisfies the Poincar{\'e} algebra. It is shown that our Poisson bracket has
the same symplectic structure that was brought in the covariant symplectic
approach.

</DOC>
<DOC>
<DOCNO> 117513 </DOCNO>
Astrometric Resolution of Severely Degenerate Binary Microlensing Events


  We investigate whether the "close/wide" class of degeneracies in
caustic-crossing binary microlensing events can be broken astrometrically.
Dominik showed that these degeneracies are particularly severe because they
arise from a degeneracy in the lens equation itself rather than a mere
"accidental" mimicking of one light curve by another. A massive observing
campaign of five microlensing collaborations was unable to break this
degeneracy photometrically in the case of the binary lensing event MACHO
98-SMC-1. We show that this degeneracy indeed causes the image centroids of the
wide and close solutions to follow an extremely similar pattern of motion
during the time when the source is in or near the caustic. Nevertheless, the
two image centroids are displaced from one another and this displacement is
detectable by observing the event at late times. Photometric degeneracies
therefore can be resolved astrometrically, even for these most severe cases.

</DOC>
<DOC>
<DOCNO> 119995 </DOCNO>
BeppoSAX Observations of the Soft Gamma-Ray Repeater SGR 1806-20


  We have observed with the BeppoSAX satellite the quiescent counterpart of the
Soft Gamma-ray Repeater SGR 1806-20. Observations performed in October 1998 and
in March 1999 showed that this pulsar continued its long term spin-down trend
at an average rate of ~8 10e-11 s/s while its flux and spectrum remained
remarkably constant between the two observations, despite the soft gamma-ray
bursting activity that occurred in this period. We also reanalyzed archival
ASCA data, that when compared with the new BeppoSAX observations, show evidence
for a long term variation in luminosity.

</DOC>
<DOC>
<DOCNO> 9855 </DOCNO>
Some remarks on the Ginsparg-Wilson fermion


  We note that Fujikawa's proposal of generalization of the Ginsparg-Wilson
relation is equivalent to setting $R = (a \gamma_5 D)^{2k}$ in the original
Ginsparg-Wilson relation $D \gamma_5 + \gamma_5 D = 2 a D R \gamma_5 D$. An
explicit realization of D follows from the Overlap construction. The general
properties of D are derived. The chiral properties of these higher-order (k >
0) realizations of Overlap Dirac operator are compared to those of the
Neuberger-Dirac operator (k = 0), in terms of the fermion propagator, the axial
anomaly and the fermion determinant in a background gauge field. Our present
results (up to lattice size 16 x 16) indicate that the chiral properties of the
Neuberger-Dirac operator are better than those of higher-order ones.

</DOC>
<DOC>
<DOCNO> 69234 </DOCNO>
Pion Lattices in HI Transverse Phase Space and Sudden Traversal of the


  Correlation data from high-energy p-p collisions indicate substantial
anticorrelation of like-sign pions and correlation of unlike-sign pions on
rapidity and azimuth at small length scale suggesting approach to a 1D lattice
structure during string hadronization. I generalize this result to propose that
an {\em incipient} 3D pion lattice structure may be formed during hadronization
of a QGP. I then present a method to detect this structure in the transverse
phase space of heavy-ion collisions which depends on local transverse Hubble
flow. I also relate this correlation structure to recently proposed suppression
of net charge and baryon-number fluctuations on rapidity after sudden traversal
of the QCD phase boundary.

</DOC>
<DOC>
<DOCNO> 84123 </DOCNO>
The Interaction of Dirac Particles with Non-Abelian Gauge Fields and


  We consider a spherically symmetric, static system of a Dirac particle
interacting with classical gravity and an SU(2) Yang-Mills field. The
corresponding Einstein-Dirac-Yang/Mills equations are derived. Using numerical
methods, we find different types of soliton-like solutions of these equations
and discuss their properties. Some of these solutions are stable even for
arbitrarily weak gravitational coupling.

</DOC>
<DOC>
<DOCNO> 14090 </DOCNO>
Universal Distribution of Centers and Saddles in Two-Dimensional


  The statistical properties of the local topology of two-dimensional
turbulence are investigated using an electromagnetically forced soap film. The
local topology of the incompressible 2D flow is characterized by the Jacobian
determinant \Lambda(x,y) = (\omega^2 - \sigma^2)/4, where \omega (x,y) is the
local vorticity and \sigma (x,y) is the local strain rate. For turbulent flows
driven by different external force configurations, P(\Lambda) is found to be a
universal function when rescaled using the turbulent intensity. A simple model
that agrees with the measured functional form of P(\Lambda) is constructed
using the assumption that the stream function, \psi(x,y), is a Gaussian random
field.

</DOC>
<DOC>
<DOCNO> 40293 </DOCNO>
Developments in Rare Kaon Decay Physics


  We review the current status of the field of rare kaon decays. The study of
rare kaon decays has played a key role in the development of the standard
model, and the field continues to have significant impact. The two areas of
greatest import are the search for physics beyond the standard model and the
determination of fundamental standard-model parameters. Due to the exquisite
sensitivity of rare kaon decay experiments, searches for new physics can probe
very high mass scales. Studies of the k->pnn modes in particular, where the
first event has recently been seen, will permit tests of the standard-model
picture of quark mixing and CP violation.

</DOC>
<DOC>
<DOCNO> 69983 </DOCNO>
Complete one-loop corrections to e+ e- -> W+ W- in the MSSM


  The complete O(\alpha) corrections including soft-photon bremsstrahlung to
the process e^+ e^- -> W^+ W^- in the MSSM are calculated for on-shell W
bosons. The relative difference between the MSSM and Standard Model corrections
is generally quite small. The maximum deviation from the Standard Model within
the scanned region of parameter space is \lesssim 1.5% for unpolarized and
transversally polarized W bosons, and \lesssim 2.7% for longitudinal W bosons.

</DOC>
<DOC>
<DOCNO> 121285 </DOCNO>
The Hamburg/RASS optical identification project


  We use digitized Schmidt direct and prism plates taken for the northern
hemisphere Hamburg Quasar Survey (HQS) to obtain optical identifications for
all high galactic latitude X-ray sources in the ROSAT Bright Source Catalogue
(RASS-BSC) at |b|>=30 deg and DEC >= 0deg. In this part of the sky the RASS-BSC
contains about 5300 X-ray sources. Presently, identifications exist for about
4100 RASS-BSC sources in this galactic latitude range.

</DOC>
<DOC>
<DOCNO> 72161 </DOCNO>
Instanton-induced Inelastic Collisions in QCD


  We show that the instanton-induced inelastic processes, leading to
multi-gluon production in in high-energy parton-parton scattering, are
considerably enhanced over the quasi-elastic ones, by a factor of 100.
  The basic instanton-induced inelastic contribution cause the parton-parton
cross section to increase as ${\rm ln} {s}$, and their Poisson resummation in
hadron-hadron scattering yield a regge-type cross section. The pomeron slope
and intercept due to instanton-induced contributions are evaluated. We show
that the small intercept is due to the diluteness of the instantons in the QCD
vacuum, while the small slope is related to the smallness of the instanton
sizes.

</DOC>
<DOC>
<DOCNO> 119846 </DOCNO>
Three high-redshift millimeter sources and their radio and near-infrared


  We present millimeter wavelength detections of three faint sources that are
most likely high-redshift starburst galaxies. For one of the sources, which was
previously discovered with SCUBA at 850 mu m, we present a detection with the
IRAM interferometer at 240 GHz (1.25 mm) that shows the object unresolved at an
angular resolution of 2.''5, and coincident within 1'' with a radio source and
a galaxy detected in the near-infrared. The two other sources were discovered
in a deep 250 GHz (1.2 mm) survey with the Max-Planck Millimeter Bolometer
(MAMBO) array at the IRAM 30m telescope. Both have fluxes of ~4 mJy and radio
counterparts with a 1.4 GHz flux density of ~75 muJy. Their radio-to-mm flux
ratios suggest redshifts larger than 2. Both sources are faint in the optical
and near-infrared, one showing a 20.5 mag K-band counterpart. From our data and
that available in the literature, we estimate the redshift distribution of
twenty-two faint mm and sub-mm sources and conclude that the majority of them
are likely to be at z>2.

</DOC>
<DOC>
<DOCNO> 8782 </DOCNO>
Transport with three-particle interaction


  Starting from a point - like two - and three - particle interaction the
kinetic equation is derived. While the drift term of the kinetic equation turns
out to be determined by the known Skyrme mean field the collision integral
appears in two - and three - particle parts. The cross section results from the
same microscopic footing and is naturally density dependent due to the three -
particle force. By this way no hybrid model for drift and cross section is
needed for nuclear transport. Besides the mean field correlation energy the
resulting equation of state has also a two - and three - particle correlation
energy which are both calculated analytically for the ground state. These
energies contribute to the equation of state and lead to an occurrence of a
maximum at 3 times nuclear density in the total energy.

</DOC>
<DOC>
<DOCNO> 119186 </DOCNO>
The Inner Boundary Condition for a Thin Disk Accreting Into a Black Hole


  Contrary to some recent claims the `no torque inner boundary condition' as
applied at the marginally stable orbit is correct for geometrically thin disks
accreting into black holes.

</DOC>
<DOC>
<DOCNO> 119524 </DOCNO>
The UV spectra of NLS1s - Implications for their broad line regions


  We study the UV spectra of NLS1 galaxies and compare them with typical
Seyfert 1 galaxies and quasars. The NLS1 spectra show narrower UV lines as well
as weaker CIV lambda 1549 and CIII] lambda 1909 emission. We show that these
line properties are due to a lower ionization parameter and somewhat higher BLR
cloud densities. These modified conditions can be explained by the hotter big
blue bumps observed in NLS1s, which are in turn due to higher L/L_Edd ratios,
as shown by our accretion disk and corona modeling of the NLS1 continua. We
also present evidence that the Boroson & Green eigenvector 1, which is
correlated with the optical and UV emission-line properties, is not driven by
orientation and hence NLS1s, which have extreme eigenvector 1 values, are not
viewed from an extreme viewing angle.

</DOC>
<DOC>
<DOCNO> 8569 </DOCNO>
Dissipative particle dynamics with energy conservation: equilibrium


  The stochastic differential equations for a model of dissipative particle
dynamics, with both total energy and total momentum conservation at every
time-step, are presented. The algorithm satisfies detailed balance as well as
the fluctuation-dissipation theorems that ensure that the proper thermodynamic
equilibrium can be reached. Macroscopic equilibrium probability distributions
as well as equations of state for the model are also derived, and an
appropriate definition of the free energy of the system is consistently
proposed. Several simulations results of equilibrium as well as transport
properties, including heat transport and thermal convection in a box, are shown
as proof of the internal consistency of the model.

</DOC>
<DOC>
<DOCNO> 69726 </DOCNO>
Bound on $\cos\alpha$ from exclusive weak radiative B decays


  We present a bound on the weak phase $\alpha$ from isospin-breaking effects
in weak radiative decays, which requires the CP-averaged branching ratios for
the weak radiative decays $B^\pm\to \rho^\pm \gamma$, $B^0\to \rho^0/\omega
\gamma$, $B\to K^* \gamma$ and the photon energy spectrum in $B\to\gamma
\ell\nu_\ell$. We carefully identify all sources of isospin breaking, which
could possibly mask information about the CKM parameters. They are introduced
by diagrams with photon bremsstrahlung off the spectator quark and diagrams
with annihilation penguin topologies. The former can be eliminated by combining
$B\to\rho\gamma$ and $B\to K^{*}\gamma$ data, whereas the latter effects are
OZI-suppressed and can be controlled by measuring also the modes $B_s\to
\rho(\omega)\gamma$. The resulting bound excludes values of $\alpha$ around
$90^\circ$, provided that the combined ratio ${\cal B}(B^\pm \to
\rho^\pm\gamma)/{\cal B}(B^0 \to \rho^0/\omega\gamma) \times {\cal B}(B^0 \to
K^{*0}\gamma)/{\cal B}(B^\pm \to K^{*\pm}\gamma)$ is found to be different from
1.

</DOC>
<DOC>
<DOCNO> 72295 </DOCNO>
Possible galactic sources of ultrahigh-energy cosmic rays and a strategy


  If decays of superheavy relic particles in the galactic halo are responsible
for ultrahigh-energy cosmic rays, these particles must be clustered to account
for small-scale anisotropy in the AGASA data. We show that the masses of such
clusters are large enough for them to gravitationally lens stars and galaxies
in the background. We propose a general strategy that can be used to detect
such clusters via gravitational lensing, or to rule out the hypothesis of
decaying relic particles as the origin of highest-energy cosmic rays.

</DOC>
<DOC>
<DOCNO> 118705 </DOCNO>
G328.4+0.2 : A large and luminous Crab-like supernova remnant


  We report on radio continuum and HI observations of the radio source
G328.4+0.2 using the Australia Telescope Compact Array. Our results confirm
G328.4+0.2 to be a filled-center nebula with no surrounding shell, showing
significant linear polarization and an almost flat spectral index. These
results lead us to conclude that G328.4+0.2 is a Crab-like, or ``plerionic'',
supernova remnant (SNR), presumably powered by an unseen central pulsar. HI
absorption towards G328.4+0.2 puts a lower limit on its distance of 17.4 +/-
0.9 kpc, making it the largest (D=25 pc) and most luminous (L_R = 3e35 erg/s)
Crab-like SNR in the Galaxy. We infer G328.4+0.2 to be significantly older than
the Crab Nebula, but powered by a pulsar which is fast spinning (P<20 ms) and
which has a comparatively low magnetic field (B<1e12 G). We propose G328.4+0.2,
G74.9+1.2 and N157B as a distinct group of large-diameter, high-luminosity
Crab-like SNRs, all powered by fast-spinning low-field pulsars.

</DOC>
<DOC>
<DOCNO> 80821 </DOCNO>
Numerical study of the scaling properties of SU(2) lattice gauge theory


  In the framework of a non-compact lattice regularization of nonabelian gauge
theories we look, in the SU(2) case, for the scaling window through the
analysis of the ratio of two masses of hadronic states. In the two-dimensional
parameter space of the theory we find the region where the ratio is constant,
and equal to the one in the Wilson regularization. In the scaling region we
calculate the lattice spacing, finding it at least 20% larger than in the
Wilson case; therefore the simulated physical volume is larger.

</DOC>
<DOC>
<DOCNO> 70720 </DOCNO>
Influence of a medium on coherent scattering of high-energy photon


  The coherent scattering of photon in the Coulomb field (the Delbr\"uck
scattering) is considered for the momentum transfer $\Delta \ll m$ in the frame
of the quasiclassical operator method. In high-energy region this process
occurs over rather long distance. The process amplitude is calculated taking
into account the multiple scattering of particles of the intermediate
electron-positron pair in a medium. The result is the suppression of the
process.

</DOC>
<DOC>
<DOCNO> 84825 </DOCNO>
Electrostatic self-energy in static black holes with spherical symmetry


  We determine the expression of the electrostatic self-energy for a point
charge in the static black holes with spherical symmetry having suitable
properties

</DOC>
<DOC>
<DOCNO> 81012 </DOCNO>
Errata and Addenda to ``Anomaly Cancellation Condition in Lattice Gauge


  We correct some intermediate expressions and arguments in hep-lat/0002009
(Nucl. Phys. B 585 (2000) 471--513). The main results do not change. We also
mention some additional observations, including a constraint on a coefficient
of the possible nontrivial anomaly which was not given in the paper.

</DOC>
<DOC>
<DOCNO> 120972 </DOCNO>
Bimodal Accretion Disks: SSD-ADAF Transitions


  We show that, unlike the results presented previously in the literature, the
transition from an outer Shakura-Sunyaev disk (SSD) to an advection-dominated
accretion flow (ADAF) is possible for large values of the viscosity parameter
$\alpha >0.5$. The transition is triggered by thermal instability of a
radiation-pressure-supported SSD. The transition radius is close to the central
black hole. We confirm our qualitative prediction by actually constructing
global bimodal SSD-ADAF solutions.

</DOC>
<DOC>
<DOCNO> 119403 </DOCNO>
Orbital dynamics of Cygnus X-3


  Orbital-phased-resolved infrared spectra of Cygnus X-3 in outburst and
quiescence, including tomographic analysis, are presented. We confirm the
phasing of broad HeII and NV lines in quiescence, such that maximum blue shift
corresponds to the X-ray minimum at phase = 0.00 +/- 0.04. In outburst,
double-peaked HeI structures show a similar phasing with two significant
differences: (a) although varying in relative strength, there is continuous
line emission in blue and red peaks around the orbit, and (b) an absorption
component, ~1/4 of an orbit out of phase with the emission features, is
discerned. Doppler tomograms of the double-peaked profiles are consistent with
a disk-wind geometry, rotating at velocities of 1000 km/s. Regrettably, the
tomography algorithm will produce a similar ring structure from alternative
line sources if contaminated by overlying P Cygni profiles. This is certainly
the case in the strong 2.0587 micron HeI line, leading to an ambiguous solution
for the nature of double-peaked emission. The absorption feature, detected 1/4
of an orbit out of phase with the emission features, is consistent with an
origin in the He star wind and yields for the first time a plausible radial
velocity curve for the system. We directly derive the mass function of the
system, 0.027 M_sun. If we assume a neutron star accretor and adopt a high
orbital inclination, i > 60 degrees, we obtain a mass range for the He star of
5 M_sun < M_WR < 11 M_sun. Alternatively if the compact object is a black hole,
we estimate M_BH < 10 M_sun. We discuss the implications of these masses for
the nature and size of the binary system.

</DOC>
<DOC>
<DOCNO> 85325 </DOCNO>
Numerical Black Hole Interiors and String Cosmology Initial Conditions


  Recent work has proposed the principle of `asymptotic past triviality' to
characterize the initial state in the pre-big bang scenario of string
cosmology, that it is a generic perturbative solution of the low-energy
effective action. Among the more generic sets of solutions which is simple
enough to investigate thoroughly, yet complex enough to exhibit interesting
behavior, is the gravity-dilaton system in spherical symmetry. Since, in the
Einstein frame, this system reduces to a massless minimally coupled scalar,
which has been target of a large body of previous investigation, we will draw
on this and interpret it in the cosmological context. Since this scenario
necessarily involves the transition from weak field initial data into the
strong field regime, gravitational collapse, we have made numerical
computations to answer some of the questions raised on the road to the proposal
that `the pre-big bang is as generic as gravitational collapse'.

</DOC>
<DOC>
<DOCNO> 72329 </DOCNO>
Search for NN-decoupled dibaryons using the process $pp \to \gamma


  The energy spectrum for high energy $\gamma$-rays ($E_\gamma \geq 10$ MeV)
from the process $pp \to \gamma \gamma X$ emitted at $90^0$ in the laboratory
frame has been measured at an energy below the pion production threshold,
namely, at 216 MeV. The resulting photon energy spectrum extracted from
$\gamma-\gamma$ coincidence events consists of a narrow peak at a photon energy
of about 24 MeV and a relatively broad peak in the energy range of (50 - 70)
MeV. The statistical significances for the narrow and broad peaks are
5.3$\sigma$ and 3.5$\sigma$, respectively. This behavior of the photon energy
spectrum is interpreted as a signature of the exotic dibaryon resonance
$d^\star_1$ with a mass of about 1956 MeV which is assumed to be formed in the
radiative process $pp \to \gamma d^\star_1$ followed by its electromagnetic
decay via the $d^\star_1 \to pp \gamma$ mode. The experimental spectrum is
compared with those obtained by means of Monte Carlo simulations.

</DOC>
<DOC>
<DOCNO> 119949 </DOCNO>
The Bright Gamma-Ray Burst 991208 - Tight Constraints on Afterglow


  The millimeter wavelength emission from GRB 991208 is the second brightest
ever detected, yielding a unique data set. We present here well-sampled spectra
and light curves over more than two decades in frequency for a two-week period.
This data set has allowed us for the first time to trace the evolution of the
characteristic synchrotron self-absorption frequency nu_a and peak frequency
nu_m, and the peak flux density F_m: we obtain nu_a \propto t^{-0.15 +- 0.12},
nu_m \propto t^{-1.7 +- 0.4}, and $_m \propto t^{-0.47 +- 0.11}. From the radio
data we find that models of homogeneous or wind-generated ambient media with a
spherically symmetric outflow can be ruled out. A model in which the
relativistic outflow is collimated (a jet) can account for the observed
evolution of the synchrotron parameters, the rapid decay at optical
wavelengths, and the observed radio to optical spectral flux distributions that
we present here, provided that the jet transition has not been fully completed
in the first two weeks after the event. These observations provide additional
evidence that rapidly decaying optical/X-ray afterglows are due to jets and
that such transitions either develop very slowly or perhaps never reach the
predicted asymptotic decay F(t) \propto t^{-p}.

</DOC>
<DOC>
<DOCNO> 122716 </DOCNO>
The formation of life


  The formation of life is an automatic stage in the consolidation of rocky or
"terrestrial" planets. The organic (=carbonaceous) matter, light elements,
gases, and water must "float" toward the surface and the heavier metals must
sink toward the center. Random processes in the molecular soup that fills
microfractures in unmelted crust eventually produce self-replicating
microtubules. In an appendix I suggest that some primordial crust remains
because there is not enough consolidation energy to melt the whole planet.
Energy is lost when iron planetesimals first partially melt and then coalesce
to form the molten iron planetary core. Stony planetesimals accrete onto the
surface of an already consolidated core.

</DOC>
<DOC>
<DOCNO> 68741 </DOCNO>
Dark Matter and Cosmic Strings in Particle Models


  In this talk, I will discuss the mechanism of nonthermal production of the
neutralino cold dark matter from the decay of cosmic strings and the embedded
defects, the $\pi$ and $\eta^\prime$ strings in the strong interaction sector
of the standard model.

</DOC>
<DOC>
<DOCNO> 116325 </DOCNO>
Simulation of Laser-Compton Cooling of Electron Beams


  We study a method of laser-Compton cooling of electron beams. Using a Monte
Carlo code, we evaluate the effects of the laser-electron interaction for
transverse cooling. The optics with and without chromatic correction for the
cooling are examined. The laser-Compton cooling for JLC/NLC at E_0=2 GeV is
considered.

</DOC>
<DOC>
<DOCNO> 12608 </DOCNO>
A Microscopic Model for D-Wave Pairing in the Cuprates: What Happens


  We present a microscopic model for a strongly repulsive electron gas on a 2D
square lattice. We suggest that nearest neighbor Coulomb repulsion stabilizes a
state in which electrons undergo a "somersault" in their internal spin-space
(spin-flux). When this spin-1/2 antiferromagnetic (AFM) insulator is doped, the
charge carriers nucleate mobile, charged, bosonic vortex solitons accompanied
by unoccupied states deep inside the Mott-Hubbard charge-transfer gap. This
model provides a unified microscopic basis for (i) non-Fermi-liquid transport
properties, (ii) mid-infrared optical absorption, (iii) destruction of AFM long
range order with doping, (iv) angled resolved spectroscopy (ARPES), and (v)
d-wave preformed charged carrier pairs. We use the Configuration Interaction
(CI) method to study the quantum translational and rotational properties of
such pairs. The CI method systematically describes fluctuation and quantum
tunneling corrections to the Hartree-Fock approximation and recaptures
essential features of the (Bethe ansatz) exact solution of the Hubbard model in
1D. For a single hole in the 2D AFM plane, we find a precursor to spin-charge
separation. The CI ground state consists of a bound vortex-antivortex pair, one
vortex carrying the charge and the other one carrying the spin of the doping
hole.

</DOC>
<DOC>
<DOCNO> 99659 </DOCNO>
Supersingular Scattering


  In 'supersingular' scattering the potential $g^2U_A(r)$ involves a variable
nonlinear parameter $A$ upon the increase of which the potential also increases
beyond all limits everywhere off the origin and develops a uniquely high level
of singularity in the origin. The problem of singular scattering is shown here
to be solvable by iteration in terms of a smooth version of the semiclassical
approach to quantum mechanics. Smoothness is achieved by working with a pair of
centrifugal strengths within each channel. In both of the exponential and
trigonometric regions, integral equations are set up the solutions of which
when matched smoothly may recover the exact scattering wave function. The
conditions for convergence of the iterations involved are derived for both
fixed and increasing parameters. In getting regular scattering solutions, the
proposed procedure is, in fact, supplementary to the Born series by widening
its scope and extending applicability from nonsingular to singular potentials
and from fixed to asymptotically increasing, linear and nonlinear, dynamical
parameters.

</DOC>
<DOC>
<DOCNO> 170071 </DOCNO>
Optimal manipulations with qubits: Universal quantum entanglers


  We analyze various scenarios for entangling two initially unentangled qubits.
In particular, we propose an optimal universal entangler which entangles a
qubit in unknown state $|\Psi>$ with a qubit in a reference (known) state
$|0>$. That is, our entangler generates the output state which is as close as
possible to the pure (symmetrized) state $(|\Psi>|0> +|0>|\Psi>)$. The most
attractive feature of this entangling machine, is that the fidelity of its
performance (i.e. the distance between the output and the ideally entangled --
symmetrized state) does not depend on the input and takes the constant value
$F= (9+3\sqrt{2})/14\simeq 0.946$. We also analyze how to optimally generate
from a single qubit initially prepared in an unknown state $|\Psi\r$ a two
qubit entangled system which is as close as possible to a Bell state
$(|\Psi\r|\Psi^\perp\r+|\Psi^\perp\r|\Psi\r)$, where $\l\Psi|\Psi^\perp\r =0$.

</DOC>
<DOC>
<DOCNO> 121062 </DOCNO>
Detection of a Series of X-ray Dips Associated with a Radio Flare in GRS


  We report the detection of a series of X-ray dips in the Galactic black hole
candidate GRS 1915+105 during 1999 June 6-17 from observations carried out with
the Pointed Proportional Counters of the Indian X-ray Astronomy Experiment on
board the Indian satellite IRS-P3. The observations were made after the source
made a transition from a steady low-hard state to a chaotic state which
occuered within a few hours. Dips of about 20-160 seconds duration are observed
on most of the days. The X-ray emission outside the dips shows a QPO at ~ 4 Hz
which has characteristics similar to the ubiquitous 0.5 - 10 Hz QPO seen during
the low-hard state of the source. During the onset of dips this QPO is absent
and also the energy spectrum is soft and the variability is low compared to the
non-dip periods. These features gradually re-appear as the dip recovers. The
onset of the occurrence of a large number of such dips followed the start of a
huge radio flare of strength 0.48 Jy (at 2.25 GHz). We interpret these dips as
the cause for mass ejection due to the evacuation of matter from an accretion
disk around the black hole. We propose that a super-position of a large number
of such dip events produces a huge radio jet in GRS 1915+105.

</DOC>
<DOC>
<DOCNO> 170607 </DOCNO>
Classical behaviour of the Dirac bispinor


  It is usually supposed that the Dirac and radiation equations predict that
the phase of a fermion will rotate through half the angle through which the
fermion is rotated, which means, via the measured dynamical and geometrical
phase factors, that the fermion must have a half-integral spin. We demonstrate
that this is not the case and that the identical relativistic quantum mechanics
can also be derived with the phase of the fermion rotating through the same
angle as does the fermion itself. Under spatial rotation and Lorentz
transformation the bispinor transforms as a four-vector like the potential and
Dirac current. Previous attempts to provide this form of transformational
behaviour have foundered because a satisfactory current could not be
derived.(14)

</DOC>
<DOC>
<DOCNO> 70458 </DOCNO>
Charged Higgs Contribution into (t b_bar)-pair Production in Hadronic


  We investigate the charged Higgs boson contribution into $t\bar b$-pair
production in pp-collisions at LHC. It is shown that due to the $\cz$-boson
exchange the total yield of $t\bar b$ is modified significantly for small and
large values of $\tan\beta$. However, for the small values of $\tan\beta$ one
should expect also the production of right-polarized top quark contrary to pure
left-polarized t-quark production through $W^{\pm}$-boson exchange only. This
fact provides a possibility to separate $H^{\pm}$ and $W^{\pm}$ contributions
by means of the investigations of angular distributions of top decay products.
The detailed simulation of the signal and relevant background processes is
performed.

</DOC>
<DOC>
<DOCNO> 120789 </DOCNO>
High-Redshift Quasars Found in Sloan Digital Sky Survey Commissioning


  This is the third paper in a series aimed at finding high-redshift quasars
from five-color (u'g'r'i'z') imaging data taken along the Celestial Equator by
the SDSS during its commissioning phase. In this paper, we first present the
observations of 14 bright high-redshift quasars (3.66<z<4.77, i^*<20)
discovered in the SDSS Fall Equatorial Stripe, and the SDSS photometry of two
previously known high-redshift quasars in the same region of the sky. Combined
with the quasars presented in previous papers, we define a color-selected
flux-limited sample of 39 quasars at 3.6 < z < 5.0 and i^*<20, covering a total
effective area of 182 deg^2. From this sample, we estimate the average spectral
power law slope in the rest-frame ultraviolet for quasars at z~4 to be -0.79
with a standard deviation of 0.34, and the average rest-frame equivalent width
of the Ly alpha+N V emission line to be 69 A with a standard deviation of 18 A.
The selection completeness of this multicolor sample is determined from the
model colors of high-redshift quasars, taking into account the distributions of
emission line strengths, intrinsic continuum slope, the line and continuum
absorption from intervening material, and the effects of photometric errors.
The average completeness of this sample is about 75%. The selection function
calculated in this paper will be used to correct the incompleteness of this
color-selected sample and to derive the high-redshift quasar luminosity
function in a subsequent paper. In the Appendix, we present the observations of
an additional 18 faint quasars (3.57<z<4.80, 20.1<i^*<20.8) discovered in the
region on the sky that has been imaged twice. Several quasars presented in this
paper exhibit interesting properties, including a radio-loud quasar at z=4.77,
and a narrow-line quasar (FWHM = 1500 km s^-1) at z=3.57.

</DOC>
<DOC>
<DOCNO> 10959 </DOCNO>
A Waveguide for Bose-Einstein Condensates


  We report on the creation of Bose-Einstein condensates of $^{87}$Rb in a
specially designed hybrid, dipole and magnetic trap. This trap naturally allows
the coherent transfer of matter waves into a pure dipole potential waveguide
based on a doughnut beam. Specifically, we present studies of the coherence of
the ensemble in the hybrid trap and during the evolution in the waveguide by
means of an autocorrelation interferometer scheme. By monitoring the expansion
of the ensemble in the waveguide we observe a mean field dominated acceleration
on a much longer time scale than in the free 3D expansion. Both the
autocorrelation interference and the pure expansion measurements are in
excellent agreement with theoretical predictions of the ensemble dynamics.

</DOC>
<DOC>
<DOCNO> 100899 </DOCNO>
Answering a question on relative countable paracompactness


  We answer a question of Yasui. Morever, we show that if a Tychonoff space Y
is countably 1-paracompact in every Tychonoff space X that contains Y as a
closed subspace then Y is linearly Lindelof.

</DOC>
<DOC>
<DOCNO> 152281 </DOCNO>
A note on dilaton absorption and near-infrared D3 brane holography


  We consider the first subleading terms in the low-energy cross section for
the absorption of dilaton partial waves by D3-branes. We demonstrate that these
corrections, computed previously via supergravity, can be reproduced exactly in
a worldvolume calculation using a deformation of N=4 SYM theory by a dimension
eight chiral operator. The calculation does not depend on how the theory is
regularized. This result provides another hint that holographic duality between
the D3-brane worldvolume theory and the corresponding supergravity solution may
be valid beyond the near horizon limit.

</DOC>
<DOC>
<DOCNO> 101751 </DOCNO>
Some Results for the Local Subgroupoids


  The notion of local subgroupoids as generalition of a local equivalence
relations was defined by the first author and R.Brown. Here we investigate some
relations between transitive components and coherence properties of the local
subgroupoids.

</DOC>
<DOC>
<DOCNO> 9928 </DOCNO>
Different hierarchy of avalanches observed in the Bak-Sneppen evolution


  We introduce a new quantity, average fitness, into the Bak-Sneppen evolution
model. Through the new quantity, a different hierarchy of avalanches is
observed. The gap equation, in terms of the average fitness, is presented to
describe the self-organization of the model. It is found that the critical
value of the average fitness can be exactly obtained. Based on the simulations,
two critical exponents, avalanche distribution and avalanche dimension, of the
new avalanches are given.

</DOC>
<DOC>
<DOCNO> 101654 </DOCNO>
Covering groups of non-connected topological groups revisited


  In general a universal covering of a non connected topological group need not
admit a topological group structure such that the covering map is a morphism of
topological groups. This result is due to R.L. Taylor (1953). We generalise
this result and relate it to the theory of obstructions to group extensions.
The methods use: the equivalence between covering maps of X and covering
groupoids of the fundamental groupoid of X; the equivalence between group
groupoids and crossed modules; and descriptions of cohomology in terms of
crossed complexes.

</DOC>
<DOC>
<DOCNO> 83497 </DOCNO>
Finding Failure Causes through Automated Testing


  A program fails. Under which circumstances does this failure occur? One
single algorithm, the delta debugging algorithm, suffices to determine these
failure-inducing circumstances. Delta debugging tests a program systematically
and automatically to isolate failure-inducing circumstances such as the program
input, changes to the program code, or executed statements.

</DOC>
<DOC>
<DOCNO> 68286 </DOCNO>
Field strength correlators in the instanton gas: The importance of the


  The field strength correlators at zero temperature are semi-classically
evaluated fitting the random instanton liquid model to lattice data for
quenched SU(3) lattice gauge theory. We restrict ourselves to the lowest order
in an instanton density expansion necessary to explain the difference between
transverse and longitudinal correlation functions. In the instanton-instanton
and instanton-antiinstanton contributions the Schwinger line factors neglected
in a previous analysis are numerically taken into account in a weighted Monte
Carlo evaluation. This leads to different estimates for instanton size and
density. A reasonable description of the correlators within the intermediate
range from 0.4 fm to 1 fm is obtained.

</DOC>
<DOC>
<DOCNO> 84709 </DOCNO>
Quantum-Mechanical Detection of Non-Newtonian Gravity


  In this work the possibility of detecting the presence of a Yukawa term, as
an additional contribution to the usual Newtonian gravitational potential, is
introduced. The central idea is to analyze the effects at quantum level
employing interference patterns (at this respect the present proposal resembles
the Colella, Overhauser and Werner experiment), and deduce from it the possible
effects that this Yukawa term could have. We will prove that the corresponding
interference pattern depends on the phenomenological parameters that define
this kind of terms. Afterwards, using the so called restricted path integral
formalism, the case of a particle whose position is being continuously
monitored, is analyzed, and the effects that this Yukawa potential could have
on the measurement outputs are obtained. This allows us to obtain another
scheme that could lead to the detection of these terms. This last part also
renders new theoretical predictions that could enable us to confront the
restricted path integral formalism against some future experiments.

</DOC>
<DOC>
<DOCNO> 70903 </DOCNO>
Features of phase ordering in (2+1)D-O(3) models


  Numerical simulations of phase ordering under dissipative dynamics in a
(2+1)-dimensional 3-vector model with O(3) symmetry are reported. The energy
functional includes terms which stabilize the size of extended topological
defects. They emerge at the end of the coarsening process as particle- or
antiparticle-like structures floating in the globally aligned vacuum.
Approximate power-law growth of disoriented domains (with an exponent near 0.4)
is found to be rather insensitive to the size of the defects. An optional
filter for conservation of winding number allows to study phase ordering in
high defect-density environment which leads to large clusters of particles
surrounded by the aligned field.

</DOC>
<DOC>
<DOCNO> 11722 </DOCNO>
Statics and dynamics of domain patterns in hexagonal-orthorhombic


  We study the statics and the dynamics of domain patterns in proper
hexagonal-orthorhombic ferroelastics; these patterns are of particular interest
because they provide a rare physical realization of disclinations in crystals.
Both our static and dynamical theories are based entirely on classical,
nonlinear elasticity theory; we use the minimal theory consistent with
stability, symmetry and ability to explain qualitatively the observed patterns.
After scaling, the only parameters of the static theory are a temperature
variable and a stiffness variable. For moderate to large stiffness, our static
results show nested stars, unnested stars, fans and other nodes, triangular and
trapezoidal regions of trapped hexagonal phase, etc observed in electron
microscopy of Ta4N and Mg-Cd alloys, and also in lead orthovanadate (which is
trigonal-monoclinic); we even find imperfections in some nodes, like those
observed. For small stiffness, we find patterns like those observed in the
mineral Mg-cordierite. Our dynamical studies of growth and relaxation show the
formation of these static patterns, and also transitory structures such as
12-armed bursts, streamers and striations which are also seen experimentally.
The major aspects of the growth-relaxation process are quite unlike those in
systems with conventional order parameters, for it is inherently nonlocal; for
example, the changes from one snapshot to the next are not predictable by
inspection.

</DOC>
<DOC>
<DOCNO> 12229 </DOCNO>
Devonshire-Landau free energy of BaTiO3 from first principles


  We have studied the Devonshire-Landau potential underlying the phase
transition sequence of BaTiO3 using the first-principles effective Hamiltonian
of Zhong, Vanderbilt, and Rabe [Phys. Rev. Lett. 73, 1861 (1994)], which has
been very successful in reproducing the phase transitions and the dielectric
and piezoelectric properties of this compound. The configuration space
(determined by the polarization P as order parameter) was explored with the
help of auxiliary electric fields. We show that the typically assumed form of
the potential, a sixth-order expansion in P around the paraelectric cubic
phase, properly accounts for the behavior of the system, but we find a
non-trivial temperature dependence for all the coefficients in the expansion,
including the quadratic one, which is shown to behave non-linearly. Our results
also prove that the sixth-order terms in the free-energy expansion (needed to
account for the first-order character of the transitions and the occurrence of
an orthorhombic phase) emerge from an interaction model that only includes
terms up to fourth order.

</DOC>
<DOC>
<DOCNO> 102768 </DOCNO>
Invitation to higher local fields, Part I, section A: Appendix to


  This appendix discusses some basic definitions and properties of differential
forms and Kato's cohomology groups in characteristic p and a sketch of the
proof of Bloch-Kato-Gabber's theorem which describes the differential symbol
from the Milnor K-group K_n(F)/p of a field F of positive characteristic p to
the differential module \Omega_F^n.

</DOC>
<DOC>
<DOCNO> 118066 </DOCNO>
The MACHO project: Microlensing Optical Depth towards the Galactic Bulge


  We present the microlensing optical depth towards the Galactic bulge based on
the detection of 99 events found in our Difference Image Analysis (DIA) survey.
This analysis encompasses three years of data, covering ~ 17 million stars in ~
4 deg^2, to a source star baseline magnitude limit of V = 23. The DIA technique
improves the quality of photometry in crowded fields, and allows us to detect
more microlensing events with faint source stars. We find this method increases
the number of detection events by 85% compared with the standard analysis
technique. DIA light curves of the events are presented and the microlensing
fit parameters are given. The total microlensing optical depth is estimated to
be tau_(total)= 2.43^(+0.39/-0.38) x 10^(-6) averaged over 8 fields centered at
l=2.68 and b=-3.35. For the bulge component we find
tau_(bulge)=3.23^(+0.52/-0.50) x 10^(-6) assuming a 25% stellar contribution
from disk sources. These optical depths are in good agreement with the past
determinations of the MACHO Alcock et al. (1997) and OGLE Udalski et al. (1994)
groups, and are higher than predicted by contemporary Galactic models. We show
that our observed event timescale distribution is consistent with the
distribution expected from normal mass stars, if we adopt the stellar mass
function of Scalo (1986) as our lens mass function. However, we note that as
there is still disagreement about the exact form of the stellar mass function,
there is uncertainty in this conclusion. Based on our event timescale
distribution we find no evidence for the existence of a large population of
brown dwarfs in the direction of the Galactic bulge.

</DOC>
<DOC>
<DOCNO> 101114 </DOCNO>
Quantum and Classic Brackets


  We describe an $p$-mechanical (see funct-an/9405002 and quant-ph/9610016)
brackets which generate quantum (commutator) and classic (Poisson) brackets in
corresponding representations of the Heisenberg group. We \emph{do not} use any
kind of semiclassic approximation or limiting procedures for $\hbar \to 0$.
Harmonic oscillator considered within the approach. Keywords: Classic and
quantum mechanics, Hamilton and Heisenberg equations, Poisson brackets,
commutator, Heisenberg group.

</DOC>
<DOC>
<DOCNO> 71046 </DOCNO>
U_A(1) symmetry breaking, scalar mesons and the nucleon spin problem in


  We establish a relationship between the scalar meson spectrum and the $U_A
(1)$ symmetry-breaking 't Hooft interaction on one hand and the constituent
quark's flavor-singlet axial coupling constant $g_{A, Q}^{(0)}$ on the other,
using an effective chiral quark field theory. This analysis leads to the new
sum rule $g_{A, Q}^{(0)}[m_{\eta '}^{2} + m_{\eta}^{2} - 2 m_{K}^{2} ]\simeq -
m_{f_{0}^{'}}^{2} - m_{f_{0}}^{2} + 2 m_{K_{0}^{*}}^{2}$, where $\eta^{'},
\eta, K$ are the observed pseudoscalar mesons, $K_{0}^{*}$ is the strange
scalar meson at 1430 MeV and $f_{0}, f_{0}^{'}$ are "the eighth and the ninth"
scalar mesons. We discuss the relationship between the constituent quark
flavor-singlet axial coupling constant $g_{A, Q}^{(0)}$ and the nucleon one
$g_{A, N}^{(0)}$ (``nucleon's spin content'') in this effective field theory.
We also relate $g_{A, Q}^{(0)}$, as well as the flavour-octet constituent quark
axial coupling constant $g_{A, Q}^{(1)}$ to vector and axial-vector meson
masses in general as well as in the tight-binding limit.

</DOC>
<DOC>
<DOCNO> 120189 </DOCNO>
Optical Imaging of Nova Shells and the Maximum Magnitude-Rate of Decline


  An optical imaging study of recent 30 novae has been undertaken using both
ground-based and space-based observations. Resolved shells have been detected
around 9 objects in the ground-based data, while another four objects have
shells detected by HST observations; for RW UMi, we fail to detect a shell
which was observed five years earlier. Images in H-alpha, and when appropriate
[O III], are shown, and finding charts for novae without shells are given if no
published chart is available. Expansion parallaxes for all systems with shells
are derived, and absolute magnitudes for a total of 28 objects are presented,
along with a discussion of the maximum magnitude-rate of decline relation. We
find that separate linear fits for fast and slow novae may be a better
representation of the data than a single, global fit. At minimum, most novae
have similar magnitudes as those of dwarf novae at maximum and novalike stars.

</DOC>
<DOC>
<DOCNO> 9991 </DOCNO>
Reacting Polymers with Highly Correlated Initial Conditions


  We propose and theoretically study an experiment designed to measure short
time polymer reaction kinetics in melts or dilute solutions. The photolysis of
groups centrally located along chain backbones, one group per chain, creates
pairs of spatially highly correlated macroradicals. We calculate time-dependent
rate coefficients $\kappa(t)$ governing their first order recombination
kinetics, which are novel on account of the far-from-equilibrium initial
conditions. In dilute solutions (good solvents) reaction kinetics are
intrinsically weak, despite the highly reactive radical groups involved. This
leads to a generalised mean field kinetics in which the rate of radical density
decay $-\ndot \twid S(t)$ where $S(t)\twid t^{-(1+g/3)}$ is the {\em
equilibrium} return probability for 2 reactive groups, given initial contact.
Here $g\approx 0.27$ is the correlation hole exponent for self-avoiding chain
ends. For times beyond the longest coil relaxation time $\tau$, $-\ndot \twid
S(t)$ remains true, but center of gravity coil diffusion takes over with rms
displacement of reactive groups $x(t)\twid t^{1/2}$ and $S(t)\twid 1/x^3(t)$.
At the shortest times ($t\lsim 10^{-6}$ sec), recombination is inhibited due to
spin selection rules and we find $\ndot \twid t S(t)$. In melts, kinetics are
intrinsically diffusion-controlled, leading to entirely different rate laws.
During the regime limited by spin selection rules, the density of radicals
decays linearly, $n(0)-n(t)\twid t$. At longer times the standard result
$-\ndot\twid dx^3(t)/dt$ (for randomly distributed ends) is replaced by
$\ndot\twid d^2x^3(t)/dt^2$ for these correlated initial conditions. The long
time behavior, $t>\tau$, has the same scaling form in time as for dilute
solutions.

</DOC>
<DOC>
<DOCNO> 170591 </DOCNO>
The effect of multi-pair signal states in quantum cryptography with


  Real sources of entangled photon pairs (like parametric down conversion) are
not perfect. They produce quantum states that contain more than only one photon
pair with some probability. In this paper it is discussed what happens if such
states are used for the purpose of quantum key distribution. It is shown that
the presence of "multi-pair" signals (together with low detection efficiencies)
causes errors in transmission even if there is no eavesdropper. Moreover, it is
shown that even the eavesdropping, that draws information only from these
"multi-pair" signals, increases the error rate. Information, that can be
obtained by an eavesdropper from these signals, is calculated.

</DOC>
<DOC>
<DOCNO> 71962 </DOCNO>
Historical roots of gauge invariance


  Gauge invariance is the basis of the modern theory of electroweak and strong
interactions (the so called Standard Model). The roots of gauge invariance go
back to the year 1820 when electromagnetism was discovered and the first
electrodynamic theory was proposed. Subsequent developments led to the
discovery that different forms of the vector potential result in the same
observable forces. The partial arbitrariness of the vector potential A brought
forth various restrictions on it. div A = 0 was proposed by J. C. Maxwell;
4-div A = 0 was proposed L. V. Lorenz in the middle of 1860's . In most of the
modern texts the latter condition is attributed to H. A. Lorentz, who half a
century later was one of the key figures in the final formulation of classical
electrodynamics. In 1926 a relativistic quantum-mechanical equation for charged
spinless particles was formulated by E. Schrodinger, O. Klein, and V. Fock. The
latter discovered that this equation is invariant with respect to
multiplication of the wave function by a phase factor exp(ieX/hc) with the
accompanying additions to the scalar potential of -dX/cdt and to the vector
potential of grad X. In 1929 H. Weyl proclaimed this invariance as a general
principle and called it Eichinvarianz in German and gauge invariance in
English. The present era of non-abelian gauge theories started in 1954 with the
paper by C. N. Yang and R. L. Mills.

</DOC>
<DOC>
<DOCNO> 11322 </DOCNO>
Hole-mediated ferromagnetism in tetrahedrally coordinated semiconductors


  A mean field model of ferromagnetism mediated by delocalized or weakly
localized holes in zinc-blende and wurzite diluted magnetic semiconductors is
presented. The model takes into account: (i) strong spin-orbit and kp couplings
in the valence band; (ii) the effect of strain upon the hole density-of-states,
and (iii) the influence of disorder and carrier-carrier interactions,
particularly near the metal-to-insulator transition. A quantitative comparison
between experimental and theoretical results for (Ga,Mn)As demonstrates that
theory describes the values of the Curie temperatures observed in the studied
systems as well as explain the directions of the easy axis and the magnitudes
of the corresponding anisotropy fields as a function of biaxial strain.
Furthermore, the model reproduces unusual sign, magnitude, and temperature
dependence of magnetic circular dichroism in the spectral region of the
fundamental absorption edge. Chemical trends and various suggestions concerning
design of novel ferromagnetic semiconductor systems are described.

</DOC>
<DOC>
<DOCNO> 150340 </DOCNO>
Hyperk\"ahler Quotients, Mirror Symmetry, and F-theory


  Using the graphical method developed in hep-th/9908082, we obtain the full
curve corresponding to the hyperk\"ahler quotient from the extended E_7 Dynkin
diagram. As in the E_6 case discussed in the same paper above, the resulting
curve is the same as the one obtained by Minahan and Nemeschansky. Our results
seem to indicate that it is possible to define a generalized Coulomb branch
such that four dimensional mirror symmetry would act by interchanging the
generalized Coulomb branch with the Higgs branch of the dual theory. To
understand these phenomena, we discuss mirror symmetry and F-theory
compactifications probed by D3 branes.

</DOC>
<DOC>
<DOCNO> 117655 </DOCNO>
Gravitational Radiation from Strongly Magnetized White Dwarfs


  The magnetic fields of white dwarfs distort their shape generating an
anisotropic moment of inertia. A magnetized white dwarf which rotates obliquely
relative to the symmetry axis has a mass quadrupole moment which varies in
time, so it will emit gravitational radiation. LISA may be able to detect the
gravitational waves from two nearby, quickly rotating white dwarfs.

</DOC>
<DOC>
<DOCNO> 40553 </DOCNO>
Preliminary Results on Charmed Meson Spectroscopy


  We report the preliminary measurement by the FOCUS Collaboration
 (E831 at Fermilab) of masses and widths of the L=1 charm mesons $D_2^{*0}$ and
$D_2^{*+}$. The fit of the invariant mass distribution requires an additional
term to account for a broad structure over background.

</DOC>
<DOC>
<DOCNO> 102911 </DOCNO>
Explicit Zeta Functions for Bosonic and Fermionic Fields on a


  Explicit formulas for the zeta functions $\zeta_\alpha (s)$ corresponding to
bosonic ($\alpha =2$) and to fermionic ($\alpha =3$) quantum fields living on a
noncommutative, partially toroidal spacetime are derived. Formulas for the most
general case of the zeta function associated to a quadratic+linear+constant
form (in {\bf Z}) are obtained. They provide the analytical continuation of the
zeta functions in question to the whole complex $s-$plane, in terms of series
of Bessel functions (of fast, exponential convergence), thus being extended
Chowla-Selberg formulas. As well known, this is the most convenient expression
that can be found for the analytical continuation of a zeta function, in
particular, the residua of the poles and their finite parts are explicitly
given there. An important novelty is the fact that simple poles show up at
$s=0$, as well as in other places (simple or double, depending on the number of
compactified, noncompactified, and noncommutative dimensions of the spacetime),
where they had never appeared before. This poses a challenge to the
zeta-function regularization procedure.

</DOC>
<DOC>
<DOCNO> 8008 </DOCNO>
An asymptotic form of the reciprocity theorem with applications in x-ray


  The emission of electromagnetic waves from a source within or near a
non-trivial medium (with or without boundaries, crystalline or amorphous, with
inhomogeneities, absorption and so on) is sometimes studied using the
reciprocity principle. This is a variation of the method of Green's functions.
If one is only interested in the asymptotic radiation fields the generality of
these methods may actually be a shortcoming: obtaining expressions valid for
the uninteresting near fields is not just a wasted effort but may be
prohibitively difficult. In this work we obtain a modified form the reciprocity
principle which gives the asymptotic radiation field directly. The method may
be used to obtain the radiation from a prescribed source, and also to study
scattering problems. To illustrate the power of the method we study a few
pedagogical examples and then, as a more challenging application we tackle two
related problems. We calculate the specular reflection of x rays by a rough
surface and by a smoothly graded surface taking polarization effects into
account. In conventional treatments of reflection x rays are treated as scalar
waves, polarization effects are neglected. This is a good approximation at
grazing incidence but becomes increasingly questionable for soft x rays and UV
at higher incidence angles.
  PACs: 61.10.Dp, 61.10.Kw, 03.50.De

</DOC>
<DOC>
<DOCNO> 99336 </DOCNO>
Magic Squares of Lie Algebras


  This paper is an investigation of the relation between Tit's magic square of
Lie algebras and certain Lie algebras of 3 times 3 and 6 times 6 matrices with
entries in alternative algebras. By reformulating Tit's definition in terms of
trialities (a generalisation of derivations), we give a systematic explanation
of the symmetry of the magic square. We show that when the columns of the magic
square are labelled by the real division algebras and the rows by their split
versions, then the rows can be interpreted as analogues of the matrix Lie
algebras su(3), sl(3) and sp(6) defined for each division algebra. We also
define another magic square based on 2 times 2 and 4 times 4 matrices and prove
that it consists of various orthogonal or (in the split case) pseudo-orthogonal
Lie algebras.

</DOC>
<DOC>
<DOCNO> 71699 </DOCNO>
epsilon'/epsilon in the Standard Model


  In order to provide an estimate of eps'/eps several effective theories and
physical effects have to be disentangled. In this talk I discuss how it is
possible to predict eps '/eps taking into account all sources of large logs.
 The numerical result one obtains, $\eps '/\eps \sim (1.7\pm 0.6) \cdot
10^{-4}$, is in good agreement with present measurements.

</DOC>
<DOC>
<DOCNO> 8618 </DOCNO>
Low-dimensional Bose liquids: beyond the Gross-Pitaevskii approximation


  The Gross-Pitaevskii approximation is a long-wavelength theory widely used to
describe a variety of properties of dilute Bose condensates, in particular
trapped alkali gases. We point out that for short-ranged repulsive interactions
this theory fails in dimensions d less than or equal to 2, and we propose the
appropriate low-dimensional modifications. For d=1 we analyze density profiles
in confining potentials, superfluid properties, solitons, and self-similar
solutions.

</DOC>
<DOC>
<DOCNO> 170179 </DOCNO>
Continuous optical loading of a Bose-Einstein Condensate


  The continuous pumping of atoms into a Bose-Einstein condensate via
spontaneous emission from a thermal reservoir is analyzed. We consider the case
of atoms with a three-level $\Lambda$ scheme, in which one of the atomic
transitions has a very much shorter life-time than the other one. We found that
in such scenario the photon reabsorption in dense clouds can be considered
negligible. If in addition inelastic processes can be neglected, we find that
optical pumping can be used to continuously load and refill Bose-Einstein
condensates, i.e. provides a possible way to achieve a continuous atom laser.

</DOC>
<DOC>
<DOCNO> 102470 </DOCNO>
The Karp complexity of unstable classes


  A class K of structures is controlled if, for all cardinals lambda, the
relation of L_{infty,lambda}-equivalence partitions K into a set of equivalence
classes (as opposed to a proper class). We prove that the class of doubly
transitive linear orders is controlled, while any pseudo-elementary class with
the omega-independence property is not controlled.

</DOC>
<DOC>
<DOCNO> 9336 </DOCNO>
Spatio-temporal structure of traffic flow in a system with an open


  The spatio-temporal structure of traffic flow pattern is investigated under
the open boundary condition using the optimal velocity (OV) model. The
parameter region where the uniform solution is convectively unstable is
determined. It is found that a localized perturbation triggers a linearly
unstable oscillatory solution out of the linearly unstable uniform state, and
it is shown that the oscillatory solution is also convectively stabilized. It
is demonstrated that the observed traffic pattern near an on-ramp can be
interpreted as the noise sustained structure in the open flow system.

</DOC>
<DOC>
<DOCNO> 69049 </DOCNO>
Neutrino Oscillations Experiments at Fermilab


  Neutrino oscillations provide an unique opportunity to probe physics beyond
the Standard Model. Fermilab is constructing two new neutrino beams to provide
a decicive test of two of the recent positive indications for neutrino
oscillations: MiniBOONE experiment will settle the LSND controversy, MINOS will
provide detailed studies of the region indicated by the SuperK results.

</DOC>
<DOC>
<DOCNO> 71029 </DOCNO>
The Little Bang: Searching for quark-gluon matter in relativistic


  I review the status of the search for quark-gluon plasma in relativistic
heavy-ion collisions. The available data provide strong evidence for the "three
pillars of the Little Bang model": strong radial expansion of the collision
fireball with Hubble-like scaling, thermal hadron emission and primordial
hadrosynthesis. It is argued that the initial state of the reaction zone
exhibits features which cannot be understood with conventional hadronic
dynamics, but are consistent with the formation of deconfined quark-gluon
matter.

</DOC>
<DOC>
<DOCNO> 13689 </DOCNO>
Magnetic circular dichroism of x-ray absorption spectroscopy at


  Magnetic circular dichroism (MCD) in the x-ray absorption spectroscopy (XAS)
at the L2,3 edges for almost entire series of rare-earth (RE) elements in
RE2Fe14B, is studied experimentally and theoretically. By a quantitative
comparison of the complicated MCD spectral shapes, we find that (i) the 4f-5d
intra-atomic exchange interaction not only induces the spin and orbital
polarization of the 5d states, which is vital for the MCD spectra of the
electric dipole transition from the 2p core states to the empty 5d conduction
band, but also it accompanies a contraction of the radial part of the 5d wave
function depending on its spin and orbital state, which results in the
enhancement of the 2p-5d dipole matrix element, (ii) there are cases where the
spin polarization of the 5d states due to the hybridization with the spin
polarized 3d states of surrounding irons plays important roles, and (iii) the
electric quadrupole transition from the 2p core states to the magnetic vale!
nce 4f states is appreciable at the pre-edge region of the dipole spectrum.
Especially, our results evidence that it is important to include the
enhancement effect of the dipole matrix element in the correct interpretation
of the MCD spectra at the RE L2,3 edges.

</DOC>
<DOC>
<DOCNO> 9900 </DOCNO>
Possible Triplet Electron Pairing and an Anisotropic Spin Susceptibility


  We argue that (TMTSF)_2 PF_6 compound under pressure is likely a triplet
superconductor with a vector order parameter d(k) \equiv (d_a(k) \neq 0, d_c(k)
= ?, d_{b'}(k) = 0); |d_a(k)| > |d_c(k)|. It corresponds to an anisotropic spin
susceptibility at T=0: \chi_{b'} = \chi_0, \chi_a \ll \chi_0, where \chi_0 is
its value in a metallic phase. [The spin quantization axis, z, is parallel to a
so-called b'-axis]. We show that the suggested order parameter explains why the
upper critical field along the b'-axis exceeds all paramagnetic limiting
fields, including that for a nonuniform superconducting state, whereas the
upper critical field along the a-axis (a \perp b') is limited by the Pauli
paramagnetic effects [I. J. Lee, M. J. Naughton, G. M. Danner and P. M.
Chaikin, Phys. Rev. Lett. 78, 3555 (1997)]. The triplet order parameter is in
agreement with the recent Knight shift measurements by I. J. Lee et al. as well
as with the early results on a destruction of superconductivity by nonmagnetic
impurities and on the absence of the Hebel-Slichter peak in the NMR relaxation
rate.

</DOC>
<DOC>
<DOCNO> 71612 </DOCNO>
New Anomalous Exchange in Regge Phenomenology and Hard Diffraction


  A new mechanism for hard diffraction based on the anomalous $f_1$ trajectory
exchange, which we identify as the odd signature partner of the Pomeron, is
suggested. We calculate the contribution of the $f_1$ exchange to elastic and
dissociative electromagnetic production of vector mesons and show that it gives
a dominant contribution to the differential cross sections at large momentum
transfers.

</DOC>
<DOC>
<DOCNO> 71446 </DOCNO>
Chiral phase transition in a covariant nonlocal NJL model


  The properties of the chiral phase transition at finite temperature and
chemical potential are investigated within a nonlocal covariant extension of
the Nambu-Jona-Lasinio model based on a separable quark-quark interaction. We
consider both the situation in which the Minkowski quark propagator has poles
at real energies and the case where only complex poles appear. In the
literature, the latter has been proposed as a realization of confinement. In
both cases, the behaviour of the physical quantities as functions of T and \mu
is found to be quite similar. In particular, for low values of T the chiral
transition is always of first order and, for finite quark masses, at certain
"end point" the transition turns into a smooth crossover. In the chiral limit,
this "end point" becomes a "tricritical" point. Our predictions for the
position of these points are similar, although somewhat smaller, than previous
estimates. Finally, the relation between the deconfining transition and chiral
restoration is also discussed.

</DOC>
<DOC>
<DOCNO> 122255 </DOCNO>
Search for companions around Sirius


  Since the discovery of Sirius-B about 130 yr ago, there have been several
claims of a possible second companion around the brightest star Sirius-A. Such
a companion could, in particular, be responsible of the suspected colour change
of the star, now strongly suggested from two independent historical sources. We
reported here on a new observation of the sky region around Sirius, to search
for such a companion, using a coronographic device.
  By comparison of the new stellar field with a similar image obtained by us
$\sim$13 yr ago and using the Sirius proper motion, we are able to eliminate
the most obvious companion candidates down to a magnitude m$_v$$\sim$17 in a
field from 30 arcsec to 2.5 arcmin of the central star. None of the visible
stars appears consistent in magnitude and colours with what expected from
current theoretical models and observations of low-mass stars.
  From the study of the same field, it is also shown that the Sirius companion,
consistently reported by observers during the years 1920-1930, is most probably
an unrelated m$_g$$\simeq$12 background star, now $\sim$ 1 arcmin away but
located precisely on the Sirius proper motion trajectory. The closest apparent
conjunction with Sirius was realized in 1937 with a minimum angular distance of
6.9 arcsec, of the same order than the Sirius A-B binary separation.
  The reported observations do not eliminate the possibility of a second
companion but now confined the search to the more central 30 arcsec region
around Sirius. In particular, the existence of a long period companion cannot
definitively be ruled out since the arbitrary orientation of the orbit can
yield an observed projected position on sky inside this more central region.

</DOC>
<DOC>
<DOCNO> 150927 </DOCNO>
The Lax pair for C_2-type Ruijsenaars-Schneider model


  We study the C_2 Ruijsenaars-Schneider(RS) model with interaction potential
of trigonometric type. The Lax pairs for the model with and without spectral
parameter are constructed. Also given are the involutive Hamiltonians for the
system. Taking nonrelativistic limit, we obtain the Lax pair of C_2
Calogero-Moser model.

</DOC>
<DOC>
<DOCNO> 118064 </DOCNO>
The Rest-Frame Optical Spectrum of MS 1512-cB58


  Moderate resolution, near-IR spectroscopy of MS1512-cB58 is presented,
obtained during commissioning of the the Near IR Spectrometer (NIRSPEC) on the
Keck II telescope. The strong lensing of this z=2.72 galaxy by the foreground
cluster MS1512+36 makes it the best candidate for detailed study of the
rest-frame optical properties of Lyman Break Galaxies.
  A redshift of z=2.7290+/-0.0007 is inferred from the emission lines, in
contrast to the z=2.7233 calculated from UV observations of interstellar
absorption lines. Using the Balmer line ratios, we find an extinction of
E(B-V)=0.27. Using the line strengths, we infer an SFR=620+/-18 Msun/yr
(H_0=75, q_0=0.1, Lambda =0), a factor of 2 higher than that measured from
narrow-band imaging observations of the galaxy, but a factor of almost 4 lower
than the SFR inferred from the UV continuum luminosity. The width of the Balmer
lines yields a mass of M_vir=1.2x10^10 Msun. We find that the oxygen abundance
is 1/3 solar, in good agreement with other estimates of the metallicity.
However, we infer a high nitrogen abundance, which may argue for the presence
of an older stellar population.

</DOC>
<DOC>
<DOCNO> 10550 </DOCNO>
Quantum Suppression of the Rayleigh Instability in Nanowires


  A linear stability analysis of metallic nanowires is performed in the
free-electron model using quantum chaos techniques. It is found that the
classical instability of a long wire under surface tension can be completely
suppressed by electronic shell effects, leading to stable cylindrical
configurations whose electrical conductance is a magic number 1, 3, 5, 6,...
times the quantum of conductance. Our results are quantitatively consistent
with recent experiments with alkali metal nanowires.

</DOC>
<DOC>
<DOCNO> 83340 </DOCNO>
Data Mining to Measure and Improve the Success of Web Sites


  For many companies, competitiveness in e-commerce requires a successful
presence on the web. Web sites are used to establish the company's image, to
promote and sell goods and to provide customer support. The success of a web
site affects and reflects directly the success of the company in the electronic
market. In this study, we propose a methodology to improve the ``success'' of
web sites, based on the exploitation of navigation pattern discovery. In
particular, we present a theory, in which success is modelled on the basis of
the navigation behaviour of the site's users. We then exploit WUM, a navigation
pattern discovery miner, to study how the success of a site is reflected in the
users' behaviour. With WUM we measure the success of a site's components and
obtain concrete indications of how the site should be improved. We report on
our first experiments with an online catalog, the success of which we have
studied. Our mining analysis has shown very promising results, on the basis of
which the site is currently undergoing concrete improvements.

</DOC>
<DOC>
<DOCNO> 9002 </DOCNO>
Robustness as an Evolutionary Principle


  We suggest to simulate evolution of complex organisms constrained by the sole
requirement of robustness in their expression patterns. This scenario is
illustrated by evolving discrete logical networks with epigenetic properties.
Evidence for dynamical features in the evolved networks is found that can be
related to biological observables.

</DOC>
<DOC>
<DOCNO> 9759 </DOCNO>
Spectral function of one hole in several one-dimensional spin


  The spectral function of one hole in different magnetic states of the
one-dimensional t-J model including three-site term and frustration
$J^{\prime}$ is studied. In the strong coupling limit $J \to 0$ (corresponding
to $U \to \infty$ of the Hubbard-model) a set of eigenoperators of the
Liouvillian is found which allows to derive an exact expression for the
one-particle Green's function that is also applicable at finite temperature and
in an arbitrary magnetic state. The spinon dispersion of the pure t-J model
with the ground-state of the Heisenberg model can be obtained by treating the
corrections due to a small exchange term by means of the projection method. The
spectral function for the special frustration $J^{\prime}=J/2$ with the
Majumdar-Ghosh wave function is discussed in detail. Besides the projection
method, a variational ansatz with the set of eigenoperators of the $t$-term is
used. We find a symmetric spinon dispersion around the momentum $k=\pi/(2a)$
and a strong damping of the holon branch. Below the continuum a bound state is
obtained with finite spectral weight and a very small separation from the
continuum. Furthermore, the spectral function of the ideal paramagnetic case at
a temperature $k_B T \gg J$ is discussed.

</DOC>
<DOC>
<DOCNO> 11435 </DOCNO>
Measuring anisotropic scattering in the cuprates


  A simple model of anisotropic scattering in a quasi two-dimensional metal is
studied. Its simplicity allows an analytic calculation of transport properties
using the Boltzmann equation and relaxation time approximation. We argue that
the c-axis magnetoresistance provides the key test of this model of transport.
We compare this model with experiments on overdoped Tl-2201 and find reasonable
agreement using only weak scattering anisotropy. We argue that optimally doped
Tl-2201 should show strong angular-dependent magnetoresistance within this
model and would provide a robust way of determining the in-plane scattering
anisotropy in the cuprates.

</DOC>
<DOC>
<DOCNO> 72118 </DOCNO>
Comment on "Nucleon elastic form factors and local duality"


  We comment on the papers "Nucleon elastic form factors and local duality"
[Phys. Rev. {\bf D62}, 073008 (2000)] and "Experimental verification of
quark-hadron duality" [Phys. Rev. Lett. {\bf 85}, 1186 (2000)]. Our main
comment is that the reconstruction of the proton magnetic form factor, claimed
to be obtained from the inelastic scaling curve thanks to parton-hadron local
duality, is affected by an artifact.

</DOC>
<DOC>
<DOCNO> 13843 </DOCNO>
Limits of the dynamical approach to non-linear response of mesoscopic


  We have considered the nonlinear response of mesoscopic systems of
non-interacting electrons to the time-dependent external field. In this
consideration the inelastic processes have been neglected and the electron
thermalization occurs due to the electron exchange with the reservoirs. We have
demonstrated that the diagrammatic technique based on the method of analytical
continuation or on the Keldysh formalism is capable to describe the heating
automatically. The corresponding diagrams contain a novel element, {\it the
loose diffuson}. We have shown the equivalence of such a diagrammatic technique
to the solution to the kinetic equation for the electron energy distribution
function. We have identified two classes of problems with different behavior
under ac pumping. In one class of problems (persistent current fluctuations,
Kubo conductance) the observable depends on the electron energy distribution
renormalized by heating. In another class of problems (Landauer conductance)
the observable is insensitive to heating and depends on the temperature of
electron reservoirs. As examples of such problems we have considered in detail
the persistent current fluctuations under ac pumping and two types of
conductance measurements (Landauer conductance and Kubo conductance) that
behave differently under ac pumping.

</DOC>
<DOC>
<DOCNO> 169762 </DOCNO>
Silicon-based Quantum Computation


  An architecture for a quantum computer is presented in which spins associated
with donors in silicon function as qubits. Quantum operations on the spins are
performed using a combination of voltages applied to gates adjacent to the
spins and radio frequency applied magnetic fields resonant with spin
transitions. Initialization and measurement of electron spins is made by
electrostatic probing of a two electron system, whose orbital configuration
must depend on the spin states of the electrons because of the Pauli Principle.
Specific devices will be discussed which perform all the necessary operations
for quantum computing, with an emphasis placed on the qualitative principles
underlying their operation.
  The likely impediments to achieving large-scale quantum computation using
this architecture will be addressed: the computer must operate at extremely low
temperature, must be fabricated from devices built with near atomic precision,
and will require extremely accurate gating operations in order to perform
quantum logic. Refinements to the computer architecture will be presented which
could remedy each of these deficiencies. I will conclude by discussing a
specific realization of the computer using Si/SiGe heterostructures into which
donors are deposited using a low energy focused ion beam.

</DOC>
<DOC>
<DOCNO> 100230 </DOCNO>
Geometry of multisymplectic Hamiltonian first-order field theories


  In the jet bundle description of Field Theories (multisymplectic models, in
particular), there are several choices for the multimomentum bundle where the
covariant Hamiltonian formalism takes place. As a consequence, several
proposals for this formalism can be stated, and, on each one of them, the
differentiable structures needed for setting the formalism are obtained in
different ways. In this work we make an accurate study of some of these
Hamiltonian formalisms, showing their equivalence.
  In particular, the geometrical structures (canonical or not) needed for the
Hamiltonian formalism, are introduced and compared, and the derivation of
Hamiltonian field equations from the corresponding variational principle is
shown in detail. Furthermore, the Hamiltonian formalism of systems described by
Lagrangians is performed, both for the hyper-regular and almost-regular cases.
  Finally, the role of connections in the construction of Hamiltonian Field
theories is clarified.

</DOC>
<DOC>
<DOCNO> 70987 </DOCNO>
The Spherical Relativistic Detonation of Scalaron Stars


  Now the hypothesis of existence of scalar fields of a various nature and
energy density in the modern Universe is intensively explored. It can explain a
nature of the dark (non- baryon) matter in the Universe and an existence of
positive $\Lambda $-term (see e.g. gr-qc/9904398). One of component of such
field has a cluster nature and organizes in the closed gravitational
configurations from galactic scales up to relativistic microscopic stars. In
the authors paper astro-ph/0008334 the hypothesis of detonation of such fields
was considered. As a result of phase transition behind the wavefront a
relativistic plasma of high energy density can appear. This process is similar
to a relativistic detonation and it can create macroscopic fireballs sufficient
for an explanation of the phenomenon of gamma-ray bursts (see e.g. the review
astro-ph/9907392). In astro-ph/0008334 it was supposed that the front of such
''detonation'' wave is entered by the flow of scalar fields with constant
energy density. If the size of the formed plasma configuration is commensurable
with the size of scalaron cluster, this hypothesis is not correct. It is
necessary to take into account a modification of the energy density of the
scalar field from centre to a periphery. It is changes the dynamics of the
fireball on principle. The indicated problem in framework of special relativity
is considered in this paper.

</DOC>
<DOC>
<DOCNO> 85237 </DOCNO>
Co-accelerated particles in the C-metric


  With appropriately chosen parameters, the C-metric represents two uniformly
accelerated black holes moving in the opposite directions on the axis of the
axial symmetry (the z-axis). The acceleration is caused by nodal singularities
located on the z-axis.
     In the~present paper, geodesics in the~C-metric are examined. In general
there exist three types of timelike or null geodesics in the C-metric:
geodesics describing particles 1) falling under the black hole horizon;
2)crossing the acceleration horizon; and 3) orbiting around the z-axis and
co-accelerating with the black holes.
     Using an effective potential, it can be shown that there exist stable
timelike geodesics of the third type if the product of the parameters of the
C-metric, mA, is smaller than a certain critical value. Null geodesics of the
third type are always unstable. Special timelike and null geodesics of the
third type are also found in an analytical form.

</DOC>
<DOC>
<DOCNO> 10675 </DOCNO>
Dielectric catastrophe at the Mott transition


  We study the Mott transition as a function of interaction strength in the
half-filled Hubbard chain with next-nearest-neighbor hopping t' by calculating
the response to an external electric field using the Density Matrix
Renormalization Group. The electric susceptibility chi diverges when
approaching the critical point from the insulating side. We show that the
correlation length xi characterizing this transition is directly proportional
to fluctuations of the polarization and that chi ~ xi^2. The critical behavior
shows that the transition is infinite-order for all t', whether or not a spin
gap is present, and that hyperscaling holds.

</DOC>
<DOC>
<DOCNO> 116742 </DOCNO>
True Transformations of Spacetime Lengths and Apparent Transformations


  It is shown in this paper that the difference between the two forms of
relativity - the ''true transformation (TT) relativity'' and - the ''apparent
transformation (AT) relativity'' is essentially caused by the difference in the
concept of \emph{sameness} of a physical system, i.e., of a physical quantity,
for different, relatively moving, observers. In the ''TT relativity'' the same
quantity for different inertial frames of reference is covariantly defined
four-dimensional (4D) tensor quantity, which transforms according to the
Lorentz transformation as the TT. In the ''AT relativity'' parts of a 4D tensor
quantity are often considered as the same quantity for different observers,
although they correspond to different quantities in 4D spacetime, and they are
not connected by the Lorentz transformation than by the AT. Then the true
transformations of a spacetime length and the apparent transformations of a
spatial distance (the Lorentz contraction) and of a temporal distance (the
usual dilatation of time) are examined in detail. It is proved that only the
true transformations of the spacetime length are in agreement with the special
relativity as the theory of a 4D spacetime with the pseudo-Euclidean geometry.

</DOC>
<DOC>
<DOCNO> 151213 </DOCNO>
Strong field limit of the Born-Infeld p-form electrodynamics


  We study the strong field limit of p-form Born-Infeld theory. It turns out
that this limiting theory is a unique theory displaying the full symmetry group
of the underlying canonical structure. Moreover, being a nonlinear theory, it
possesses an infinite hierarchy of conservation laws.

</DOC>
<DOC>
<DOCNO> 117522 </DOCNO>
Disc instability models for X-ray transients: evidence for evaporation


  We construct time-dependent models of accretion discs around black holes and
neutron stars. We investigate the effect of evaporating the disc inner regions
during quiescence on the predictions of the Disc Instability Model (DIM) for
these systems. We do not include irradiation of the disc in the models.
  Removing the inner, most unstable parts of the accretion disc increases the
predicted recurrence times. However, DIMs with values of the viscosity
parameter alpha_hot ~ 0.1 and alpha_cold ~ 0.02 (typical of applications of the
DIM to standard dwarf nova outbursts) fail to reproduce the long recurrence
times of SXTs (unless we resort to fine-tuning of the parameters) independent
of the evaporation strength. We show that models with evaporation and a smaller
value of alpha_cold (~ 0.005) do reproduce the long recurrence times and the
accretion rates at the level of the Eddington rate observed in outburst. The
large difference between the values of alpha_hot and alpha_cold, if confirmed
when disc irradiation is included, suggests that several viscosity mechanisms
operate in these accretion discs.
  For some choices of parameters our models predict reflares during the decline
from outburst. They are a physical property of the model and result from a
heating front forming in the wake of an initial cooling front and subsequent,
multiple front reflections. The reflares disappear in low-alpha models where
front reflection can not occur.

</DOC>
<DOC>
<DOCNO> 80922 </DOCNO>
Structure Functions on the lattice


  We report on a lattice computation of the second moment of the pion matrix
element of the twist-2 non-singlet operator corresponding to the average
momentum of parton densities. We apply a fully non-perturbatively evaluated
running renormalization constant as well as a careful extrapolation of our
results to the continuum limit. Thus the only limitation of our final result is
the quenched approximation.

</DOC>
<DOC>
<DOCNO> 11687 </DOCNO>
Microscopic Theory of Damon-Eshbach Modes in Ferromagnetic Films


  The surface spin wave branches in ferromagnetic films are studied using a
microscopic theory which considers both magnetic dipole-dipole and Heisenberg
exchange interactions. The dipole terms are expressed in a Hamiltonian
formalism, and the dipole sums are calculated in a rapidly convergent form. The
Damon-Eshbach surface modes are analyzed for different directions of the
spin-wave propagation and also for different ratios of the strength of the
dipole interactions relative to the exchange interactions. Numerical results
are presented using parameters for Fe and GdCl$_3$.

</DOC>
<DOC>
<DOCNO> 68602 </DOCNO>
The Wave Function of 2S Radially Excited Vector Mesons from Data for


  In the color dipole gBFKL dynamics we predict a strikingly different Q^2 and
energy dependence of the diffraction slope for the elastic production of ground
state V(1S) and radially excited V'(2S) light vector mesons. The color dipole
model predictions for the diffraction slope for \rho^0 and \phi^0 production
are in a good agreement with the data from the fixed target and collider HERA
experiments. We present how a different form of anomalous energy and Q^2
dependence of the diffraction slope for V'(2S) production leads to a different
position of the node in radial wave function and discuss a possibility how to
determine this position from the fixed target and HERA data.

</DOC>
<DOC>
<DOCNO> 9595 </DOCNO>
Ab-initio prediction of the electronic and optical excitations in


  We calculate the electronic and optical excitations of polythiophene using
the GW approximation for the electronic self-energy, and include excitonic
effects by solving the electron-hole Bethe-Salpeter equation. Two different
situations are studied: excitations on isolated chains and excitations on
chains in crystalline polythiophene. The dielectric tensor for the crystalline
situation is obtained by modeling the polymer chains as polarizable line
objects, with a long-wavelength polarizability tensor obtained from the
ab-initio polarizability function of the isolated chain. With this model
dielectric tensor we construct a screened interaction for the crystalline case,
including both intra- and interchain screening. In the crystalline situation
both the quasi-particle band gap and the exciton binding energies are
drastically reduced in comparison with the isolated chain. However, the optical
gap is hardly affected. We expect this result to be relevant for conjugated
polymers in general.

</DOC>
<DOC>
<DOCNO> 83284 </DOCNO>
The Quantum Complexity of Set Membership


  We study the quantum complexity of the static set membership problem: given a
subset S (|S| \leq n) of a universe of size m (m \gg n), store it as a table of
bits so that queries of the form `Is x \in S?' can be answered. The goal is to
use a small table and yet answer queries using few bitprobes. This problem was
considered recently by Buhrman, Miltersen, Radhakrishnan and Venkatesh, where
lower and upper bounds were shown for this problem in the classical
deterministic and randomized models. In this paper, we formulate this problem
in the "quantum bitprobe model" and show tradeoff results between space and
time.In this model, the storage scheme is classical but the query scheme is
quantum.We show, roughly speaking, that similar lower bounds hold in the
quantum model as in the classical model, which imply that the classical upper
bounds are more or less tight even in the quantum case. Our lower bounds are
proved using linear algebraic techniques.

</DOC>
<DOC>
<DOCNO> 178766 </DOCNO>
Pairing anti-halo effect


  We discuss pairing correlations in weakly bound neutron rich nuclei, by using
the coordinate-space Hartree-Fock-Bogolyubov approach which allows to take
properly into account the coupling to particle continuum. We show that the
additional pairing binding energy acts against a development of an infinite rms
radius, even in situations when an l=0 single-particle orbital becomes unbound.

</DOC>
<DOC>
<DOCNO> 71460 </DOCNO>
Electroweak Corrections to the Top Quark Decay


  We have calculated the one-loop electroweak corrections to the decay t-> bW+,
including the counterterm for the CKM matrix elements V(tb). Previous
calculations used an incorrect delta V(tb) that led to a gauge dependent
amplitude. However, since the contribution stemming from delta V(tb) is small,
those calculations only underestimate the width by roughly one part in 10^5.

</DOC>
<DOC>
<DOCNO> 68668 </DOCNO>
CP Violation in the SM and Beyond in Hadronic B Decays


  Three different methods, using $B_d\to J/\psi K_S$, $J/\psi K_S \pi^0$,
$B_d\to K^-\pi^+, \pi^+\pi^-$ and $B_u\to K^- \pi^0, \bar K^0 \pi^-,
\pi^-\pi^0$, to extract hadronic model independent information about new
physics are discussed in this talk.

</DOC>
<DOC>
<DOCNO> 13345 </DOCNO>
Dirac quasiparticles in the mixed state


  Energies and wave functions are calculated for d-wave quasiparticles in the
mixed state using the formalism of Franz and Tesanovic for the low-lying energy
levels. The accuracy of the plane-wave expansion is explored by comparing
approximate to exact results for a simplified one-dimensional problem, and the
convergence of the plane- wave expansion to the two-dimensional case is
studied. The results are used to calculate the low-energy tunneling density of
states and the low-temperature specific heat, and these theoretical results are
compared to semiclassical treatments and to the available data. Implications
for the muon spin resonance measurements of vortex core size are also
discussed.

</DOC>
<DOC>
<DOCNO> 118060 </DOCNO>
The evolution of helium white dwarfs: III. On the ages of millisecond


  We employed recently computed evolutionary white-dwarf models with helium
cores, supplemented by heavier models with carbon-oxygen cores, in order to
investigate the ages of millisecond pulsar systems based on the cooling
properties of the compact companions. Contrary to the behaviour of more massive
white dwarfs, the evolutionary speed of low-mass white-dwarf models is
substantially slowed down by ongoing hydrogen burning. By comparing the cooling
ages of these models with the spin-down ages of the pulsars for those systems
for which reasonable information about the compact companions is available, we
found good correspondence between both ages. Based on these models any
revisions concerning the temporal evolution of millisecond pulsars do not
appear to be necessary.

</DOC>
<DOC>
<DOCNO> 99697 </DOCNO>
Asymptotic homomorphisms into the Calkin algebra


  Let $A$ be a separable $C^*$-algebra and let $B$ be a stable $C^*$-algebra
with a strictly positive element. We consider the (semi)group $\Ext^{as}(A,B)$
(resp. $\Ext(A,B)$) of homotopy classes of asymptotic (resp. of genuine)
homomorphisms from $A$ to the corona algebra $M(B)/B$ and the natural map
$i:\Ext(A,B)\ar\Ext^{as}(A,B)$. We show that if $A$ is a suspension then
$\Ext^{as}(A,B)$ coincides with $E$-theory of Connes and Higson and the map $i$
is surjective. In particular any asymptotic homomorphism from $SA$ to $M(B)/B$
is homotopic to some genuine homomorphism.

</DOC>
<DOC>
<DOCNO> 68327 </DOCNO>
Width effects in slepton production e+ e- --> ~mu_R ~mu_R


  A case study will be presented to investigate width effects in the precise
determination of slepton masses at the e+e- TESLA Linear Collider.

</DOC>
<DOC>
<DOCNO> 170009 </DOCNO>
Geometric phases for mixed states in interferometry


  We provide a physical prescription based on interferometry for introducing
the total phase of a mixed state undergoing unitary evolution, which has been
an elusive concept in the past. We define the parallel transport condition that
provides a connection-form for obtaining the geometric phase for mixed states.
The expression for the geometric phase for mixed state reduces to well known
formulas in the pure state case when a system undergoes noncyclic and unitary
quantum evolution.

</DOC>
<DOC>
<DOCNO> 39679 </DOCNO>
Standard Model: An Introduction


  We present a primer on the Standard Model of the electroweak interaction.
Emphasis is given to the historical aspects of the theory's formulation. The
radiative corrections to the Standard Model are presented and its predictions
for the electroweak parameters are compared with the precise experimental data
obtained at the Z pole. Finally, we make some remarks on the perspectives for
the discovery of the Higgs boson, the most important challenge of the Standard
Model.

</DOC>
<DOC>
<DOCNO> 85333 </DOCNO>
Scharnhorst effect at oblique incidence


  We consider the Scharnhorst effect (anomalous photon propagation in the
Casimir vacuum) at oblique incidence, calculating both photon speed and
polarization states as functions of angle. The analysis is performed in the
framework of nonlinear electrodynamics and we show that many features of the
situation can be extracted solely on the basis of symmetry considerations.
Although birefringence is common in nonlinear electrodynamics it is not
universal; in particular we verify that the Casimir vacuum is not birefringent
at any incidence angle. On the other hand, group velocity is typically not
equal to phase velocity, though the distinction vanishes for special directions
or if one is only working to second order in the fine structure constant. We
obtain an ``effective metric'' that is subtly different from previous results.
The disagreement is due to the way that ``polarization sums'' are implemented
in the extant literature, and we demonstrate that a fully consistent
polarization sum must be implemented via a bootstrap procedure using the
effective metric one is attempting to define. Furthermore, in the case of
birefringence, we show that the polarization sum technique is intrinsically an
approximation.

</DOC>
<DOC>
<DOCNO> 80789 </DOCNO>
Approximation of the determinant of large sparse symmetric positive


  This paper is concerned with the problem of approximating the determinant of
A for a large sparse symmetric positive definite matrix A. It is shown that an
efficient solution of this problem is obtained by using a sparse approximate
inverse of A. The method is explained and theoretical properties are discussed.
A posteriori error estimation techniques are presented. Furthermore, results of
numerical experiments are given which illustrate the performance of this new
method.

</DOC>
<DOC>
<DOCNO> 8866 </DOCNO>
Correlations of triggering noise in driven magnetic clusters


  We show that the temporal fluctuations $\Delta H(t)$ of the threshold driving
field $H(t)$, which triggers an avalanche in slowly driven disordered
ferromagnets with many domains, exhibit long-range correlations in space and
time. The probability distribution of the distance between {\it successive}
avalanches as well as the distribution of trapping times of domain wall at a
given point in space have fractal properties with the universal scaling
exponents. We show how these correlations are related to the scaling behavior
of Barkhausen avalanches occurring by magnetization reversal. We also suggest a
transport equation which takes into account the observed noise correlations.

</DOC>
<DOC>
<DOCNO> 102678 </DOCNO>
Derived Categories of Twisted Sheaves on Elliptic Threefolds


  We construct an equivalence between the derived category of sheaves on an
elliptic threefold without a section and a derived category of twisted sheaves
(modules over an Azumaya algebra) on any small resolution of its relative
Jacobian.

</DOC>
<DOC>
<DOCNO> 116767 </DOCNO>
The BaBar Calorimeter Light Pulser System


  To make precision measurements with a CsI(Tl) calorimeter in a high
luminosity environment requires that the crystals are well calibrated and
continually monitored for radiation damage. This should not effect the total
integrated luminosity which is particularly important for the \babar
calorimeter to enable it to make CP violation measurements in the $B$ meson
system. To achieve this goal a fibre-optic light pulser system was designed
using xenon flash lamps as the light source. A novel light distribution method
was developed using an array of graded index microlenses. Some initial results
from performance studies are presented.

</DOC>
<DOC>
<DOCNO> 83294 </DOCNO>
Incremental construction of minimal acyclic finite-state automata


  In this paper, we describe a new method for constructing minimal,
deterministic, acyclic finite-state automata from a set of strings. Traditional
methods consist of two phases: the first to construct a trie, the second one to
minimize it. Our approach is to construct a minimal automaton in a single phase
by adding new strings one by one and minimizing the resulting automaton
on-the-fly. We present a general algorithm as well as a specialization that
relies upon the lexicographical ordering of the input strings.

</DOC>
<DOC>
<DOCNO> 100415 </DOCNO>
Characterization of the atomic space $H^1$ for non doubling measures in


  Let $\mu$ be a Radon measure on $R^d$, which may be non doubling. The only
condition that $\mu$ must satisfy is $\mu(B(x,r))\leq C r^n$, for all $x,r$ and
for some fixed $0<n\leq d$. Recently we introduced spaces of type $BMO(\mu)$
and $H^1(\mu)$ which proved to be useful to study the $L^p(\mu)$ boundedness of
Calder\'on-Zygmund operators without assuming doubling conditions. In this
paper a characterization of the new atomic space $H^1(\mu)$ in terms of a grand
maximal operator $M_\Phi$ is given. It is shown that $f$ belongs to $H^1(\mu)$
iff $f\in L^1(\mu)$, $\int f d\mu=0$ and $M_\Phi(f)\in L^1(\mu)$, as in the
usual doubling situation. The lack of any regularity condition on $\mu$, apart
from the size condition stated above, is one of the main difficulties that
appears when one tries to extend the classical arguments to the present
situation.

</DOC>
<DOC>
<DOCNO> 70373 </DOCNO>
Meson Mixing and Dilepton Production in Heavy Ion Collisions


  We study the possibility of $\rho-a_0$ mixing via N-N excitations in dense
nuclear matter. This mixing is found to induce a peak in the dilepton spectra
at an invariant mass equal to that of the $a_0$. We calculate the cross section
for dilepton production through mixing and we compare its size with that of
$\pi-\pi$ annihilation. In-medium masses and mixing angles are also calculated.
Some preliminary results of the mixing effect on the dilepton production rates
at finite temperature are also presented.

</DOC>
<DOC>
<DOCNO> 69495 </DOCNO>
Decays and Lifetime of B_c in QCD Sum Rules


  In the framework of three-point QCD sum rules, the form factors for the
semileptonic decays of B_c^+ -> B_s(B_s^*) l \nu are calculated with account
for the Coulomb-like alpha_s/v-corrections in the heavy quarkonium. The
generalized relations due to the spin symmetry of HQET/NRQCD for the form
factors are derived at the recoil momentum close to zero. The nonleptonic
decays are studied using the assumption on the factorization. The B_c meson
lifetime is estimated by summing up the dominating exclusive modes in the c ->
s transition combining the current calculations with the previous analysis of b
-> c decays in the sum rules of QCD and NRQCD.

</DOC>
<DOC>
<DOCNO> 99465 </DOCNO>
A characterization of semiampleness and contractions of relative curves


  A line bundle with a base-point-free multiple is called semiample. I give a
cohomological characterization of semiample line bundles. The result is a
common generalization of the Fujita-Zariski criterion for semiampleness and the
Grothendieck-Serre characterization of ampleness. Applying the Fujita-Zariski
Theorem, I characterize contractible curves in 1-dimensional families.

</DOC>
<DOC>
<DOCNO> 84932 </DOCNO>
Classicity from Entangled Ensemble States of Knotted Spin Networks. A


  Referring to a conception put forward by Stuart Kauffman in his
"Investigations", it is shown how the onset of classicity can be visualized in
terms of an emergent process originating in entangled ensemble states of
knotted spin networks. The latter exhibit a suitable autocatalytic behaviour
effectively producing knots by knots acting upon other knots. In particular, a
quantum computational structure can be described underlying spin networks such
that most conditions for a partial ordering are not more valid for the latter.
A concep- tual argument is given then indicating that on a fundamental level,
physics is non-local and a-temporal, and hence does not admit of the concept of
causality. Hence, modelling the emergence of classicity in terms of a
percolating web of coherence eventually decohering (in using a cellular
automata architecture) does not imply the necessity of visualizing histories of
directed percolation as causal sets. These aspects are compatible though with
the recent concept of spin foams which do not actually imply distinguished
directions of time flow on the micro-level.

</DOC>
<DOC>
<DOCNO> 10672 </DOCNO>
High field magnetotransport in composite conductors: the effective


  The self consistent effective medium approximation (SEMA) is used to study
three-dimensional random conducting composites under the influence of a strong
magnetic field {\bf B}, in the case where all constituents exhibit isotropic
response. Asymptotic analysis is used to obtain almost closed form results for
the strong field magnetoresistance and Hall resistance in various types of two-
and three-constituent isotropic mixtures for the entire range of compositions.
Numerical solutions of the SEMA equations are also obtained, in some cases, and
compared with those results. In two-constituent
free-electron-metal/perfect-insulator mixtures, the magnetoresistance is
asymptotically proportional to $|{\bf B}|$ at {\em all concentrations above the
percolation threshold}. In three-constituent metal/insulator/superconductor
mixtures a line of critical points is found, where the strong field
magnetoresistance switches abruptly from saturating to non-saturating
dependence on $|{\bf B}|$, at a certain value of the
insulator-to-superconductor concentration ratio. This transition appears to be
related to the phenomenon of anisotropic percolation.

</DOC>
<DOC>
<DOCNO> 118491 </DOCNO>
Space VLBI at Low Frequencies


  At sufficiently low frequencies, no ground-based radio array will be able to
produce high resolution images while looking through the ionosphere. A
space-based array will be needed to explore the objects and processes which
dominate the sky at the lowest radio frequencies. An imaging radio
interferometer based on a large number of small, inexpensive satellites would
be able to track solar radio bursts associated with coronal mass ejections out
to the distance of Earth, determine the frequency and duration of early epochs
of nonthermal activity in galaxies, and provide unique information about the
interstellar medium. This would be a "space-space" VLBI mission, as only
baselines between satellites would be used. Angular resolution would be limited
only by interstellar and interplanetary scattering.

</DOC>
<DOC>
<DOCNO> 119376 </DOCNO>
Constraints on dark matter physics from dwarf galaxies through galaxy


  One of the predictions of the standard CDM is that dark haloes have centrally
divergent density profiles. An extensive body of rotation curve observations of
dwarf and low surface brightness galaxies shows the dark haloes of those
systems to be characterized by soft constant density central cores. Several
physical processes have been proposed to produce soft cores in dark haloes,
each one with different scaling properties. With the aim of discriminating
among them we have examined the rotation curves of dark matter dominated dwarf
and low surface brightness galaxies and the inner mass profiles of two clusters
of galaxies lacking a central cD galaxy and with evidence of soft cores in the
centre. The core radii and central densities of these haloes scale in a well
defined manner with the depth of their potential wells, as measured through the
maximum circular velocity. As a result of our analysis we identify
self-interacting CDM as a viable solution to the core problem, where a
non-singular isothermal core is formed in the halo center surrounded by a
Navarro, Frenk, & White profile in the outer parts. We show that this
particular physical situation predicts core radii in agreement with
observations. Furthermore, using the observed scalings, we derive an expression
for the minimum cross section (\sigma) which has an explicit dependence with
the halo dispersion velocity (v). If m_x is the mass of the dark matter
particle: \sigma/m_x ~4 10^-25 (v/100 km s^-1)^-1 cm^2/Gev.

</DOC>
<DOC>
<DOCNO> 39881 </DOCNO>
Why the Four SM Families


  The flavor democracy favors the existence of the nearly degenerate fourth SM
family, whereas the fifth SM family is disfavored both by the mass
phenomenology and precision tests of the Standard Model. The multi-hundreds GeV
fourth family quarks will be copiously produced at the LHC. However, the first
indication of the fourth family may come from the Higgs search at the upgraded
Tevatron.

</DOC>
<DOC>
<DOCNO> 69118 </DOCNO>
Precise predictions for W-pair production at LEP2 with RACOONWW


  RACOONWW is the first Monte Carlo generator for e+e- --> WW --> 4f(+gamma)
that includes the electroweak O(alpha) radiative corrections in the double-pole
approximation completely. Some numerical results for LEP2 energies are
discussed, and the predictions for the total W-pair cross section are
confronted with LEP2 data.

</DOC>
<DOC>
<DOCNO> 169927 </DOCNO>
Dynamic generation of maximally entangled photon multiplets by adiabatic


  The adiabatic passage scheme for quantum state synthesis, in which atomic
Zeeman coherences are mapped to photon states in an optical cavity, is extended
to the general case of two degenerate cavity modes with orthogonal
polarization. Analytical calculations of the dressed-state structure and Monte
Carlo wave-function simulations of the system dynamics show that, for a
suitably chosen cavity detuning, it is possible to generate states of photon
multiplets that are maximally entangled in polarization. These states display
nonclassical correlations of the type described by Greenberger, Horne, and
Zeilinger (GHZ). An experimental scheme to realize a GHZ measurement using
coincidence detection of the photons escaping from the cavity is proposed. The
correlations are found to originate in the dynamics of the adiabatic passage
and persist even if cavity decay and GHZ state synthesis compete on the same
time scale. Beyond entangled field states, it is also possible to generate
entanglement between photons and the atom by using a different atomic
transition and initial Zeeman state.

</DOC>
<DOC>
<DOCNO> 123056 </DOCNO>
Clustering Segregation With UV Luminosity in Lyman-Break Galaxies at z~3


  We report on the clustering properties of Lyman-break galaxies (LBGs) at z~3.
The correlation length of flux-limited samples of LBGs depends on their
rest-frame ultraviolet (UV) luminosity at lambda ~1700 Angstrom, with fainter
galaxies being less strongly clustered in space. It decreases by a factor ~3
over the range of limiting magnitudes that we have probed, namely 25<R<27,
suggesting that fainter samples include galaxies with smaller mass. We find
that: 1) the clustering strength of LBGs follows, within the errors, the same
scaling law with the volume density predicted for cold dark matter (CDM) halos;
2) the scaling law predicted for the galaxies using the halos mass spectrum and
a number of models for the relationship that maps the halos' mass into the
galaxies' UV luminosity depends only on how tightly mass and UV luminosity
correlate, but is otherwise insensitive to the details of the models. These
results provide additional evidence that the strong spatial clustering of LBGs
is due to galaxy biasing, supporting biased galaxy formation and gravitational
instability as the primary mechanism for the formation of structure. We also
find that 1) a scale invariant relationship between mass and UV luminosity
(e.g. a power law) is not supported, suggesting that the properties of star
formation of galaxies change along the mass spectrum of the observed LBGs; 2)
the scatter of the UV luminosity of LBGs of given mass must be relatively small
for massive LBGs, suggesting that the mass is an important parameter in
regulating the activity of star formation in these systems, and that the
fraction of massive halos at z~3 that are not observed in UV-selected surveys
is not large.

</DOC>
<DOC>
<DOCNO> 8271 </DOCNO>
d- and p-wave superconductivity mediated by spin fluctuations in two-


  We have systematically studied superconducting instabilities in the repulsive
Hubbard model for d-wave and p-wave pairing in various 2D and 3D lattices.
Using fluctuation exchange approximation, we consider 3D face centered cubic
lattice, 3D body centered cubic lattice, 3D simple cubic lattice, 2D square
lattice and 2D triangular lattice, where either strong ferro- or
antiferromagnetic spin fluctuation is present. We show that (i) d-wave
instability mediated by antiferromagnetic spin fluctuations is stronger than
p-wave instability mediated by ferromagnetic spin fluctuations both in 2D and
3D, and (ii)d-wave instability in 2D is much stronger than that in 3D. These
amount that the "best" situation is the antiferromagnetic-fluctuation mediated
in 2D as far as the single-band Hubbard model on ordinary lattices are
concerned.

</DOC>
<DOC>
<DOCNO> 13204 </DOCNO>
Localization in ruthenates: magnetic and electronic properties of


  The electronic structures of the metallic and insulating phases of
Ca(2-x)Sr(x)RuO(4) (0<= x <= 2) are calculated using LDA, LDA+U and Dynamical
Mean-Field Approximation methods. For x=0 the ground state is an orbitally
non-degenerate antiferromagnetic insulator. For 0.2<x<0.5 we propose a state
with partial orbital and spin ordering. For x>0.5 the observed Curie-Weiss
paramagnetic metallic state possessing a local moment with the unexpected spin
S=1/2 is explained by the localization of only two of the three Ru-4d-orbitals.

</DOC>
<DOC>
<DOCNO> 150796 </DOCNO>
Gravitational anomalies in a dispersive approach


  The gravitational anomalies in two dimensions, specifically the Einstein
anomaly and the Weyl anomaly, are fully determined by means of dispersion
relations. In this approach the anomalies originate from the peculiar infrared
feature of the imaginary part of the relevant formfactor which approaches a
$\delta$-function singularity at zero momentum squared when $m \to 0$.

</DOC>
<DOC>
<DOCNO> 69826 </DOCNO>
Dynamics of barrier penetration in thermal medium: exact result for


  Time evolution of quantum tunneling is studied when the tunneling system is
immersed in thermal medium. We analyze in detail the behavior of the system
after integrating out the environment. Exact result for the inverted harmonic
oscillator of the tunneling potential is derived and the barrier penetration
factor is explicitly worked out as a function of time. Quantum mechanical
formula without environment is modifed both by the potential renormalization
effect and by a dynamical factor which may appreciably differ from the
previously obtained one in the time range of 1/(curvature at the top of
potential barrier).

</DOC>
<DOC>
<DOCNO> 174518 </DOCNO>
Multifragmentation of a very heavy nuclear system (II): bulk properties


  The properties of fragments and light charged particles emitted in
multifragmentation of single sources formed in central 36AMeV Gd+U collisions
are reviewed. Most of the products are isotropically distributed in the
reaction c.m. Fragment kinetic energies reveal the onset of radial collective
energy. A bulk effect is experimentally evidenced from the similarity of the
charge distribution with that from the lighter 32AMeV Xe+Sn system. Spinodal
decomposition of finite nuclear matter exhibits the same property in simulated
central collisions for the two systems, and appears therefore as a possible
mechanism at the origin of multifragmentation in this incident energy domain.

</DOC>
<DOC>
<DOCNO> 84663 </DOCNO>
Perfect fluid space-times admitting a 3-dimensional conformal group


  Space-times admitting a 3-dimensional Lie group of conformal motions $C_3$
acting on null orbits are studied. Coordinate expressions for the metric and
the conformal Killing vectors (CKV) are then provided (irrespectively of the
matter content) and all possible perfect fluid solutions are found, although
none of them verifies the weak and dominant energy conditions over the whole
space-time manifold.

</DOC>
<DOC>
<DOCNO> 152356 </DOCNO>
Numerical Aspects of Bubble Nucleation


  Bubble nucleation has been studied on lattices using phenomenological
Langevin equations. Recently there have been theoretical motivations for using
these equations. These studies also conclude that the simple Langevin
description requires some modification. We study bubble nucleation on a lattice
and determine effects of the modified Langevin equations.

</DOC>
<DOC>
<DOCNO> 117765 </DOCNO>
The X-ray spectrum of a disk illuminated by ions


  The X-ray spectrum from a cool disk embedded in an ion supported torus is
computed. The interaction of the hot ions with the disk increases the hard
X-ray luminosity of the system}. A surface layer of the disk is heated by the
protons from the torus. The Comptonized spectrum produced by this layer has a
shape that depends only weakly on the incident energy flux and the distance
from the accreting compact object. It consists of a `blue bump' of
unComptonized soft photons and a flat high energy tail, reminiscent of the
observed spectra. The hard tail becomes flatter as the thermalization depth in
the cool disk is increased. Further evidence for ion illumination are the Li
abundance in the secondaries of low mass X-ray binaries and the 450 keV lines
sometimes seen in black-hole transient spectra.

</DOC>
<DOC>
<DOCNO> 117473 </DOCNO>
W UMa-type Binary Stars in Globular Clusters


  A sample of 86 contact binary systems in 14 globular clusters with available
color index data in (B-V) or in (V-I) has been analyzed. At least one third of
all systems are numerous foreground Galactic Disk projections over long lines
of sight to the clusters. Since the selection of the cluster members has been
based on the MV(logP, color) calibrations, the matter of a
metallicity-correction required particular attention with the result that such
a correction is apparently not needed at the present level of accuracy.
Analysis of the color-magnitude and period-color relations shows that globular
cluster members are under-luminous relative to the Galactic Disk contact
systems mainly because of the smaller sizes and, consequently, shorter orbital
periods; the color-index effect of the diminished blanketing is less important,
especially for (V-I). The variability amplitudes for the Blue Straggler systems
show a significantly different distribution from that for systems below the
Turn Off Point (TOP): The BS systems show only small amplitudes while the
distribution for the systems below the TOP is peculiar in containing only large
amplitude systems. This difference is linked to an observational selection
effect so that efforts at determining the frequency of occurrence of the
contact systems below the TOP have been judged to be premature; the frequency
among the BS stars could be at about 45+-10 BS stars per one contact BS binary.

</DOC>
<DOC>
<DOCNO> 13507 </DOCNO>
Absorption of Energy at a Metallic Surface due to a Normal Electric


  The effect of an oscillating electric field normal to a metallic surface may
be described by an effective potential. This induced potential is calculated
using semiclassical variants of the random phase approximation (RPA). Results
are obtained for both ballistic and diffusive electron motion, and for two and
three dimensional systems. The potential induced within the surface causes
absorption of energy. The results are applied to the absorption of radiation by
small metal spheres and discs. They improve upon an earlier treatment which
used the Thomas-Fermi approximation for the effective potential.

</DOC>
<DOC>
<DOCNO> 70027 </DOCNO>
Renormalization Group Flow Equations and the Phase Transition in


  We derive and solve flow equations for a general O(N)-symmetric effective
potential including wavefunction renormalization corrections combined with a
heat-kernel regularization. We investigate the model at finite temperature and
study the nature of the phase transition in detail. Beta functions, fixed
points and critical exponents \beta, \nu, \delta and \eta for various N are
independently calculated which allow for a verification of universal scaling
relations.

</DOC>
<DOC>
<DOCNO> 122925 </DOCNO>
Direct N-body Modelling of Stellar Populations: Blue Stragglers in M67


  We present a state-of-the-art N-body code which includes a detailed treatment
of stellar and binary evolution as well as the cluster dynamics. This code is
ideal for investigating all aspects relating to the evolution of star clusters
and their stellar populations. It is applicable to open and globular clusters
of any age. We use the N-body code to model the blue straggler population of
the old open cluster M67. Preliminary calculations with our binary population
synthesis code show that binary evolution alone cannot explain the observed
numbers or properties of the blue stragglers. On the other hand, our N-body
model of M67 generates the required number of blue stragglers and provides
formation paths for all the various types found in M67. This demonstrates the
effectiveness of the cluster environment in modifying the nature of the stars
it contains and highlights the importance of combining dynamics with stellar
evolution. We also perform a series of N = 10000 simulations in order to
quantify the rate of escape of stars from a cluster subject to the Galactic
tidal field.

</DOC>
<DOC>
<DOCNO> 122194 </DOCNO>
AMRA: An Adaptive Mesh Refinement Hydrodynamic Code for Astrophysics


  Implementation details and test cases of a newly developed hydrodynamic code,
AMRA, are presented. The numerical scheme exploits the adaptive mesh refinement
technique coupled to modern high-resolution schemes which are suitable for
relativistic and non-relativistic flows. Various physical processes are
incorporated using the operator splitting approach, and include self-gravity,
nuclear burning, physical viscosity, implicit and explicit schemes for
conductive transport, simplified photoionization, and radiative losses from an
optically thin plasma. Several aspects related to the accuracy and stability of
the scheme are discussed in the context of hydrodynamic and astrophysical
flows.

</DOC>
<DOC>
<DOCNO> 71087 </DOCNO>
Lepton Flavor Violation at the LHC


  Recent results from Super Kamiokande suggest $\nu_\mu-\nu_\tau$ mixing and
hence lepton flavor violation. In supersymmetric models, this flavor violation
may have implications for the pattern of slepton masses and mixings. Possible
signals for this mixing in the decays of sleptons produced at the LHC are
discussed. The sensitivity expected is compared to that of rare decays such as
$\tau\to \mu\gamma$.

</DOC>
<DOC>
<DOCNO> 152531 </DOCNO>
From stochastic quantization to bulk quantization: Schwinger-Dyson


  In stochastic quantization, ordinary 4-dimensional Euclidean quantum field
theory is expressed as a functional integral over fields in 5 dimensions with a
fictitious 5th time. This is advantageous, in particular for gauge theories,
because it allows a different type of gauge fixing that avoids the Gribov
problem. Traditionally, in this approach, the fictitious 5th time is the analog
of computer time in a Monte Carlo simulation of 4-dimensional Euclidean fields.
A Euclidean probability distribution which depends on the 5th time relaxes to
an equilibrium distribution. However a broader framework, which we call ``bulk
quantization", is required for extension to fermions, and for the increased
power afforded by the higher symmetry of the 5-dimensional action that is
topological when expressed in terms of auxiliary fields. Within the broader
framework, we give a direct proof by means of Schwinger-Dyson equations that a
time-slice of the 5-dimensional theory is equivalent to the usual 4-dimensional
theory. The proof does not rely on the conjecture that the relevant stochastic
process relaxes to an equilibrium distribution. Rather, it depends on the
higher symmetry of the 5-dimensional action which includes a BRST-type
topological invariance, and invariance under translation and inversion in the
5-th time. We express the physical S-matrix directly in terms of the truncated
5-dimensional correlation functions, for which ``going off the mass-shell''
means going from the 3 physical degrees of freedom to 5 independent variables.
We derive the Landau-Cutokosky rules of the 5-dimensional theory which include
the physical unitarity relation.

</DOC>
<DOC>
<DOCNO> 178397 </DOCNO>
Correlation and Finite Interaction-Range Effects in High-Energy Electron


  We calculate cross sections of high energy electron inclusive scattering off
nuclear matter in a new and consistent formulation based on the Green's
function method with the Glauber approximation, which is an extension of our
previous work on the nuclear transparency in (e, e'p) reaction. The comparison
with other approaches is discussed. In this framework, we study the
finite-range effect of the nucleon-nucleon interaction in the final-state
interactions, and the effect of the nuclear short-range correlation. We propose
a zero-range approximation, which works well when correlation and finite
interaction-range effects are included. It greatly reduces the numerical work,
while maintaining a reasonable accuracy.

</DOC>
<DOC>
<DOCNO> 13971 </DOCNO>
Microscopic theory of quadrupolar ordering in TmTe


  We have calculated the crystal electric field of TmTe (T>T_Q) and have
obtained that the ground state of a Tm 4f hole is the $\Gamma_7$ doublet in
agreement with Mossbauer experiments. We study the quadrupole interactions
arising from quantum transitions of 4f holes of Tm. An effective attraction is
found at the L point of the Brillouin zone, $\vec{q}_L$. Assuming that the
quadrupolar condensation involves a single arm of $\vec{q}_L$ we show that
there are two variants for quadrupole ordering which are described by the space
groups C2/c and C2/m. The Landau free energy is derived in mean-field theory.
The phase transition is of second order. The corresponding quadrupole order
parameters are combinations of $T_{2g}$ and $E_g$ components. The obtained
domain structure is in agreement with observations from neutron diffraction
studies for TmTe. Calculated lattice distortions are found to be different for
the two variants of quadrupole ordering. We suggest to measure lattice
displacements in order to discriminate between those two structures.

</DOC>
<DOC>
<DOCNO> 9677 </DOCNO>
Magnetic Excitations in the Spin Gap System TlCuCl$_3$


  Single-crystal neutron inelastic scattering was performed in order to
investigate the magnetic excitations in the spin gap system TlCuCl$_3$. The
constant-${\bf Q}$ energy scan profiles were collected in the $a^*-c^*$ plane.
Three excitations are observed for $E{\leq}15$ meV. One of the excitations is
identified to be magnetic excitation. The lowest magnetic excitation with
$E\sim 0.5$ meV occurs at ${\bf Q}=(1, 0, 1)$, as observed in KCuCl$_3$. The
dispersion relation of the magnetic excitation can be fitted to the dispersion
formula derived from the weakly coupled dimer model. The intradimer interaction
is evaluated as $J=5.23$ meV, which coincides with the value estimated from the
susceptibility data. However, one of the interdimer interactions obtained is so
large that the weakly coupled dimer model is broken down.

</DOC>
<DOC>
<DOCNO> 116925 </DOCNO>
Beam Loading Compensation in the Main Linac of CLIC


  Compensation of multi-bunch beam loading is of great importance in the main
linac of the Compact Linear Collider (CLIC). The bunch-to-bunch energy
variation has to stay below 1 part in 1000. In CLIC, the RF power is obtained
by decelerating a drive beam which is formed by merging a number of short bunch
trains. A promising scheme for tackling beam loading in the main linac is based
on varying the lengths of the bunch trains in the drive beam. The scheme and
its expected performance are presented.

</DOC>
<DOC>
<DOCNO> 39746 </DOCNO>
Upper Limits in the Case That Zero Events are Observed: An Intuitive


  We compare the ``unified approach'' for the estimation of upper limits with
an approach based on the Bayes theory, in the special case that no events are
observed. The ``unified approach'' predicts, in this case, an upper limit that
decreases with the increase in the expected level of background. This seems
absurd. On the other hand, the Bayesian approach leads to a result which is
background independent. An explanation of the Bayesian result is presented,
together with suggested reasons for the paradoxical result of the ``unified
approach''.

</DOC>
<DOC>
<DOCNO> 178752 </DOCNO>
Three-body analysis of incoherent $\eta$-photoproduction on the deuteron


  A three-body calculation of the reaction $\gamma d\to\eta np$ in the energy
region from threshold up to 30 MeV above has been performed. The primary goal
of this study is to assess the importance of the three-body aspects in the
hadronic sector of this reaction. Results are presented for the $\eta$-meson
spectrum as well as for the total cross section. The three-body results differ
significantly from those predicted by a simple rescattering model in which only
first-order $\eta N$- and $NN$-interactions in the final state are considered.
The major features of the experimental data are well reproduced although right
at threshold the rather large total cross section could not be explained.

</DOC>
<DOC>
<DOCNO> 117159 </DOCNO>
On the four dimensional Conformal Anomaly, Fractal Spacetime and the


  Antoniadis, Mazur and Mottola (AMM) two years ago computed the intrinsic
Hausdorff dimension of spacetime at the infrared fixed point of the quantum
conformal factor in 4D Gravity. The fractal dimension was determined by the
coefficient of the Gauss-Bonnet topological term associated with the conformal
gravitational anomaly and was found to be greater than 4. It is explicitly
shown how one can relate the value of the Hausdorff dimension computed by AMM
to the universal dimensional fluctuation of spacetime $\epsilon $ given by
$\phi^3/2$, where $\phi$ is the Golden Mean $0.618..$. Based on the infrared
scaling limit of the theory and using recent Renormalization Group arguments by
El Naschie, we conjecture that the unknown coefficient $Q^2$, associated with
the four dimensional gravitational conformal anomaly, could be precisely equal
to the inverse fine structure constant values ranging between $137.036 $ and
137.081. Our results generate decimal digits up to any $arbitrary$ number.

</DOC>
<DOC>
<DOCNO> 10130 </DOCNO>
Acoustic collective excitations and static dielectric response in


  Starting from the basic Landau model for the incommensurate-commensurate
materials of the class II, we derive the spectrum of collective modes for all
(meta)stable states from the corresponding phase diagram. It is shown that all
incommensurate states posses Goldstone modes with acoustic dispersions. The
representation in terms of collective modes is also used in the calculation and
discussion of static dielectric response for systems with the commensurate wave
number in the center of the Brillouin zone.

</DOC>
<DOC>
<DOCNO> 152556 </DOCNO>
Non-commutative Branes from M-theory


  The analysis of the worldvolume effective actions of the M-theory
Kaluza-Klein monopole and 9-brane suggests that it should be possible to
describe non-abelian configurations of M2-branes or M5-branes if the M2-branes
are transverse to the eleventh direction and the M5-branes are wrapped on it.
This is determined by the fact that the Kaluza-Klein monopole and the M9-brane
are constrained to move in particular isometric spacetimes. We show that the
same kind of situation is implied by the analysis of the brane descent
relations in M-theory. We compute some of the non-commutative couplings of the
worldvolume effective actions of these non-abelian systems of M2 and M5 branes
and show that they indicate the existence of configurations corresponding to N
branes expanding into a higher dimensional M-brane. The reduction to Type II
brings up new descriptions of coincident D-branes at strong coupling. We show
that these systems have the right non-commutative charges to describe certain
expanded configurations playing a role in the framework of the AdS/CFT
correspondence. Finally, we discuss the realization of non-commutative brane
configurations as topological solitons in non-abelian brane-antibrane systems.

</DOC>
<DOC>
<DOCNO> 71821 </DOCNO>
Shadowing Effects on Vector Boson Production


  We explore how nuclear modifications to the nucleon structure functions,
shadowing, affect massive gauge boson production in heavy ion collisions at
different impact parameters. We calculate the dependence of $Z^0$, $W^+$ and
$W^-$ production on rapidity and impact parameter to next-to-leading order in
Pb+Pb collisions at 5.5 TeV/nucleon to study quark shadowing at high $Q^2$. We
also compare our Pb+Pb results to the $pp$ rapidity distributions at 14 TeV.

</DOC>
<DOC>
<DOCNO> 121708 </DOCNO>
Superconducting Superfluids in Neutron Stars


  For treatment of the layers below the crust of a neutron star it is useful to
employ a relativistic model involving three independently moving constituents,
representing superfluid neutrons, superfluid protons, and degenerate negatively
charged leptons. A Kalb Ramond type formulation is used here to develop such a
model for the specific purpose of application at the semi macroscopic level
characterised by lengthscales that are long compared with the separation
between the highly localised and densely packed proton vortices of the
Abrikosov type lattice that carries the main part of the magnetic flux, but
that are short compared with the separation between the neutron vortices.

</DOC>
<DOC>
<DOCNO> 11884 </DOCNO>
Parametric Luminescence of Microcavity Polaritons


  The spectral and dispersive emission properties are analytically determined
for the two-dimensional system of exciton-polaritons in microcavities excited
by a resonant and coherent optical pump. New collective excitations result from
the anomalous coupling between one generic polariton state and its idler,
created by the scattering of two pumped polaritons. The corresponding
parametric correlation is stimulated by the emitter and idler populations and
drives very efficiently the luminescence. The intrinsic properties of the
collective excitations determine a peculiar emission pattern.

</DOC>
<DOC>
<DOCNO> 80899 </DOCNO>
Noisy Monte Carlo Algorithm


  We present an exact Monte Carlo algorithm designed to sample theories where
the energy is a sum of many couplings of decreasing strength. The algorithm
avoids the computation of almost all non-leading terms. Its use is illustrated
by simulating SU(2) lattice gauge theory with a 5-loop improved action. A new
approach for dynamical fermion simulations is proposed.

</DOC>
<DOC>
<DOCNO> 99571 </DOCNO>
A characterisation of Pfaffian near bipartite graphs


  In 1967 Kasteleyn introduced a powerful method for enumerating the 1-factors
of planar graphs. In fact his method can be extended to graphs which permit an
orientation under which every alternating circuit is clockwise odd. Graphs with
this property are called {\it Pfaffian}. Little characterised Pfaffian
bipartite graphs in terms of forbidden subgraphs in 1975. We extend his
characterisation to near bipartite graphs.

</DOC>
<DOC>
<DOCNO> 39738 </DOCNO>
The Physical Significance of Confidence Intervals


  We define some appropriate statistical quantities that indicate the physical
significance (reliability) of confidence intervals in the framework of both
Frequentist and Bayesian statistical theories. We consider the expectation
value of the upper limit in the absence of a signal (that we propose to call
"exclusion potential", instead of "sensitivity" as done by Feldman and Cousins)
and its standard deviation, we define the "Pull" of a null result, expressing
the reliability of an experimental upper limit, and the "upper and lower
detection functions", that give information on the possible outcome of an
experiment if there is a signal. We also give a new appropriate definition of
"sensitivity", that quantifies the capability of an experiment to reveal the
signal that is searched for at the given confidence level.

</DOC>
<DOC>
<DOCNO> 178950 </DOCNO>
The structure of lambda hypernuclei


  The density dependent relativistic hadron field theory is extended to also
describe strange systems. It is seen that the application to hypernuclei works
extremely well. Important spin orbit effects in lambda hypernuclei are studied
and their experimental relevance is pointed out.

</DOC>
<DOC>
<DOCNO> 70371 </DOCNO>
Coherence Effects in Diffractive Electroproduction of rho Mesons from


  A systematic multiple scattering formalism for vector meson electroproduction
from nuclei is developed, with emphasis on the formation, propagation and
hadronization scales for quark-gluon fluctuations of the virtual high-energy
photon. The theory is compared to HERMES measurements of rho electroproduction
on 14N. The nuclear transparency as a function of the vector meson propagation
length is well reproduced.

</DOC>
<DOC>
<DOCNO> 10480 </DOCNO>
Electron correlation induced transverse delocalization and longitudinal


  Electron-electron interactions in general lead to both ground state and
excited state confinement. We show, however, that in phenyl-substituted
polyacetylenes electron-electron interactions cause enhanced delocalization of
quasiparticles in the optically excited state from the backbone polyene chain
into the phenyl groups, which in turn leads to enhanced confinement in the
chain direction. This co-operative delocalization--confinement lowers the
energy of the one-photon state and raises the relative energy of the lowest
two-photon state. The two-photon state is slightly below the optical state in
mono-phenyl substituted polyacetylenes, but above the optical state in
di-phenyl substituted polyacetylenes, thereby explaining the strong
photoluminescence of the latter class of materials. We present a detailed
mechanism of the crossover in the energies of the one- and two-photon states in
these systems. In addition, we calculate the optical absorption spectra over a
wide wavelength region, and make specific predictions for the polarizations of
low and high energy transitions that can be tested on oriented samples. Within
existing theories of light emission from $\pi$-conjugated polymers, strong
photoluminescence should be restricted to materials whose optical gaps are
larger than that of trans-polyacetylene. The present work show that
conceptually at least, it is possible to have light emission from systems with
smaller optical gaps.

</DOC>
<DOC>
<DOCNO> 100128 </DOCNO>
Strongly n-trivial Knots


  A knot k is called ``strongly (n-1)-trivial.'' if there exists a projection
of k, such that one can choose n crossings of the projection with the property
that making the crossing changes corresponding to any of the $2^{n}-1$
nontrivial combinations of the selected crossings turns the original knot into
the unknot. We prove that given any non-trivial knot k of genus g, k fails to
be strongly n-trivial for all $n, n \geq 3g-1$.

</DOC>
<DOC>
<DOCNO> 70694 </DOCNO>
Centrality dependence of multiplicities in ultrarelativistic nuclear


  We compute the centrality dependence of multiplicities of particles produced
in ultrarelativistic nuclear collisions at various energies and atomic numbers.
The computation is carried out in perturbative QCD with saturated densities of
produced gluons and by including effects of nuclear geometry. Numbers are given
for Au+Au collisions at RHIC energies.

</DOC>
<DOC>
<DOCNO> 178496 </DOCNO>
LOCV calculation for Beta-stable matter at finite temperature


  The method of lowest-order constrained variational, which predicts reasonably
the nuclear matter semi-empirical data is used to calculate the equation of
state of beta-stable matter at finite temperature. The Reid soft-core with and
without the N-$\Delta$ interactions which fits the N-N scattering data as well
as the $UV_{14}$ potential plus the three-nucleon interaction are considered in
the nuclear many-body Hamiltonian. The electron and muon are treated
relativistically in the total Hamiltonian at given temperature, to make the
fluid electrically neutral and stable against beta decay. The calculation is
performed for a wide range of baryon density and temperature which are of
interest in the astrophysics. The free energy, entropy, proton abundance, etc.
of nuclear beta-stable matter are calculated.
 It is shown that by increasing the temperature, the maximum proton abundance
is pushed to the lower density while the maximum itself increases as we
increase the temperature. The proton fraction is not enough to see any
gas-liquid phase transition. Finally we get an overall agreement with other
many-body techniques, which are available only at zero temperature.

</DOC>
<DOC>
<DOCNO> 69004 </DOCNO>
Spectra of Doubly Heavy Quark Baryons


  Baryons containing two heavy quarks are treated in the Born-Oppenheimer
approximation. Schr\"odinger equation for two center Coulomb plus harmonic
oscillator potential is solved by the method of ethalon equation at large
intercenter separations. Asymptotical expansions for energy term and wave
function are obtained in the analytical form. Using those formulas, the energy
spectra of doubly heavy baryons with various quark compositions are calculated
analytically.

</DOC>
<DOC>
<DOCNO> 117152 </DOCNO>
Role and meaning of subjective probability: some comments on common


  Criticisms of so called `subjective probability' come on the one hand from
those who maintain that probability in physics has only a frequentistic
interpretation, and, on the other, from those who tend to `objectivise'
Bayesian theory, arguing, e.g., that subjective probabilities are indeed based
`only on private introspection'. Some of the common misconceptions on
subjective probability will be commented upon in support of the thesis that
coherence is the most crucial, universal and `objective' way to assess our
confidence on events of any kind.

</DOC>
<DOC>
<DOCNO> 101992 </DOCNO>
Van Kampen's embedding obstruction for discrete groups


  We give a lower bound to the dimension of a contractible manifold on which a
given group can act properly discontinuously. In particular, we show that the
$n$-fold product of nonabelian free groups cannot act properly discontinuously
on $\R^{2n-1}$.

</DOC>
<DOC>
<DOCNO> 10608 </DOCNO>
Macroscopic quantum coherence in antiferromagnetic molecular magnets


  The macroscopic quantum coherence in a biaxial antiferromagnetic molecular
magnet in the presence of magnetic field acting parallel to its hard anisotropy
axis is studied within the two-sublattice model. On the basis of instanton
technique in the spin-coherent-state path-integral representation, both the
rigorous Wentzel-Kramers-Brillouin exponent and preexponential factor for the
ground-state tunnel splitting are obtained. We find that the quantum
fluctuations around the classical paths can not only induce a new quantum phase
previously reported by Chiolero and Loss (Phys. Rev. Lett. 80, 169 (1998)), but
also have great influnence on the intensity of the ground-state tunnel
splitting. Those features clearly have no analogue in the ferromagnetic
molecular magnets. We suggest that they may be the universal behaviors in all
antiferromagnetic molecular magnets. The analytical results are complemented by
exact diagonalization calculation.

</DOC>
<DOC>
<DOCNO> 116329 </DOCNO>
Soliton electro-optic effects in paraelectrics


  The combination of charge separation induced by the formation of a single
photorefractive screening soliton and an applied external bias field in a
paraelectric is shown to lead to a family of useful electro-optic guiding
patterns and properties.

</DOC>
<DOC>
<DOCNO> 68931 </DOCNO>
Gradient Terms in the Microscopic Description of K-Atoms


  We analyze the spectra of kaonic atoms using optical potentials withnon-local
(gradient) terms. The magnitude of the non-local termsfollows from a self
consistent many-body calculation of the kaon selfenergy in nuclear matter,
which is based on s-wave kaon nucleoninteractions. The optical potentials
exhibit strong non-linearitiesin the nucleon density and sizeable non-local
terms. We find that thenon-local terms are quantitatively important in the
analysis of thespectra and that a phenomenologically successful description can
be obtained for p-wave like optical potentials. It is suggested that
themicroscopic form of the non-local interaction terms is
obtainedsystematically by means of a semi-classical expansion of the
nucleusstructure. The resulting optical potential leads to less pronounced
non-local effects.

</DOC>
<DOC>
<DOCNO> 10235 </DOCNO>
The Geometrical Structure of 2d Bond-Orientational Order


  We study the formulation of bond-orientational order in an arbitrary two
dimensional geometry. We find that bond-orientational order is properly
formulated within the framework of differential geometry with torsion. The
torsion reflects the intrinsic frustration for two-dimensional crystals with
arbitrary geometry. Within a Debye-Huckel approximation, torsion may be
identified as the density of dislocations. Changes in the geometry of the
system cause a reorganization of the torsion density that preserves
bond-orientational order. As a byproduct, we are able to derive several
identities involving the topology, defect density and geometric invariants such
as Gaussian curvature. The formalism is used to derive the general free energy
for a 2D sample of arbitrary geometry, both in the crystalline and hexatic
phases. Applications to conical and spherical geometries are briefly addressed.

</DOC>
<DOC>
<DOCNO> 122588 </DOCNO>
The Red-Sequence Cluster Survey: The Value of $\Omega_m$ and $\sigma_8$


  The Red-Sequence Cluster Survey (RCS) is a 100 deg$^2$ optical survey for
high-redshift galaxy clusters. One of the goals of the survey is a measurement
of $\Omega_m$ and $\sigma_8$ via the evolution of the mass spectrum of galaxy
clusters. Herein we briefly describe how this will initially be done, and also
demonstrate the eventual power of the RCS for this type of measurement by a
qualitative analysis of the first 1/10th of the survey data.

</DOC>
<DOC>
<DOCNO> 120378 </DOCNO>
Hubble Space Telescope Photometry of the Dwarf Spheroidal Galaxy ESO


  We present HST WFPC2 imaging of the nearby low-surface-brightness dwarf
spheroidal galaxy ESO 410-G005, which has been resolved into stars for the
first time. The resulting color-magnitude diagram for about 2500 stars shows a
red giant branch branch with a tip at I=(22.4+-0.15), which yields a distance
of D=(1.9+-0.2) Mpc. ESO 410-G005 is found to be metal-poor with a mean
metallicity of (-1.8+-0.4) dex estimated from its red giant branch. Upper
asymptotic giant branch stars appear to be present near the center of the
galaxy, indicative of a substantial, centrally concentrated intermediate-age
population, unless these objects are artifacts of crowding. Previous studies
did not detect ESO 410-G005 in H alpha or in HI. ESO 410-G005 is a probable
member of the Sculptor group. Its linear separation from the nearest spiral,
NGC 55, is 230 kpc on the sky. The deprojected separation ranges from 340 to
615 kpc depending on the assumed distance of NGC 55. ESO 410 G005 appears to be
a relatively isolated dSph within the Sculptor group. Its absolute magnitude,
Mv = (-12.1+-0.2) mag, its central surface brightness, mu_V = (22.7+-0.1)
mag/arcsec^2, and its mean metallicity, [Fe/H] = (-1.8+-0.4) dex, follow the
trend observed for dwarf galaxies in the Local Group. (abridged)

</DOC>
<DOC>
<DOCNO> 71220 </DOCNO>
Evolution of cosmological perturbations in a brane-universe


  The present article analyses the impact on cosmology, in particular on the
evolution of cosmological perturbations, of the existence of extra-dimensions.
The model considered here is that of a five-dimensional Anti-de Sitter
spacetime where ordinary matter is confined to a brane-universe. The
homogeneous cosmology is recalled. The equations governing the evolution of
cosmological perturbations are presented in the most transparent way: they are
rewritten in a form very close to the equations of standard cosmology with two
types of corrections: a. corrections due to the unconventional evolution of the
homogeneous solution, which change the background-dependent coefficients of the
equations; b. corrections due to the curvature along the fifth dimension, which
act as source terms in the evolution equations.

</DOC>
<DOC>
<DOCNO> 80708 </DOCNO>
Monte Carlo Studies of the IIB Matrix Model at Large N


  The low-energy effective theory of the IIB matrix model developed by H. Aoki
et al. is written down explicitly in terms of bosonic variables only. The
effective theory is then studied by Monte Carlo simulations in order to
investigate the possibility of a spontaneous breakdown of Lorentz invariance.
The imaginary part of the effective action, which causes the so-called sign
problem in the simulation, is dropped by hand. The extent of the eigenvalue
distribution of the bosonic matrices shows a power-law large N behavior,
consistent with a simple branched-polymer prediction. We observe, however, that
the eigenvalue distribution becomes more and more isotropic in the
ten-dimensional space-time as we increase N. This suggests that if the
spontaneous breakdown of Lorentz invariance really occurs in the IIB matrix
model, a crucial role must be played by the imaginary part of the effective
action.

</DOC>
<DOC>
<DOCNO> 117943 </DOCNO>
The Least-Action Principle: Theory of Cosmological Solutions and the


  Formulating the equations of motion for cosmological bodies (such as
galaxies) in an integral, rather than differential, form has several
advantages. Using an integral the mathematical instability at early times is
avoided and the boundary conditions of the integral correspond closely with
available data. Here it is shown that such a least-action calculation for a
number of bodies interacting by gravity has a finite number of solutions,
possibly only one. Characteristics of the different possible solutions are
explored. The results are extended to cover the motion of a continuous fluid. A
method to generalize an action to use velocities, instead of positions, in
boundary conditions, is given, which reduces in particular cases to those given
by Giavalisco et al. (1993) and Schmoldt & Saha (1998). The velocity boundary
condition is shown to have no effect on the number of solutions.

</DOC>
<DOC>
<DOCNO> 100724 </DOCNO>
A Fourier-Mukai approach to spectral data for instantons


  We study U(r) instantons on elliptic surfaces with a section and show that
they are in one-one correspondence with spectral data consisting of a curve in
the dual elliptic surface and a line bundle on that curve. We use relative
Fourier-Mukai transforms to analyse their properties and, in the case of the K3
and abelian surfaces, we show that the moduli space of instantons has a natural
Lagrangian fibration with respect to the canonical complex symplectic
structure.

</DOC>
<DOC>
<DOCNO> 123023 </DOCNO>
Evidence for a source size of less than 2000 AU in Quasar 2237+0305


  Recently, OGLE team have reported clear quasar microlensing signal in
Q2237+0305. We have analyzed the microlens event of ``image C'' by using their
finely and densely sampled lightcurves. From lightcurve fitting, we can
unambiguously set the source size of $\lsim 0.98$ Einstein Ring radius as a
conservative limit. This limit corresponds to $2000 {\rm (AU)}$, if we adopt
 $M_{\rm lens} \sim 0.1M_{\odot}$ obtained by a recent statistical study of
mean mass of lens object. This gives a clear evidence for the existence of an
accretion disk in the central region of the quasar.

</DOC>
<DOC>
<DOCNO> 83046 </DOCNO>
A Parallel Algorithm for Dilated Contour Extraction from Bilevel Images


  We describe a simple, but efficient algorithm for the generation of dilated
contours from bilevel images. The initial part of the contour extraction is
explained to be a good candidate for parallel computer code generation. The
remainder of the algorithm is of linear nature.

</DOC>
<DOC>
<DOCNO> 68822 </DOCNO>
Properties of cosmologies with dynamical pseudo Nambu-Goldstone bosons


  We study observational constraints on cosmological models with a quintessence
field in the form of a dynamical pseudo Nambu-Goldstone boson. After reviewing
the properties of the solutions, from a dynamical systems phase space analysis,
we consider the constraints on parameter values imposed by luminosity distances
from the 60 Type Ia supernovae published by Perlmutter et al., and also from
gravitational lensing statistics of distant quasars. In the case of the Type Ia
supernovae we explicitly allow for the possibility of evolution of the peak
luminosities of the supernovae sources, using simple empirical models which
have been recently discussed in the literature. We find weak evidence to
suggest that the models with supernovae evolution fit the data better in the
context of the quintessence models in question. If source evolution is a
reality then the greatest challenge facing these models is the tension between
current value of the expansion age, H_0 t_0, and the fraction of the critical
energy density, Omega_{phi0}, corresponding to the scalar field. Nonetheless
there are ranges of the free parameters which fit all available cosmological
data.

</DOC>
<DOC>
<DOCNO> 169875 </DOCNO>
Geometric Quantum Computation


  We describe in detail a general strategy for implementing a conditional
geometric phase between two spins. Combined with single-spin operations, this
simple operation is a universal gate for quantum computation, in that any
unitary transformation can be implemented with arbitrary precision using only
single-spin operations and conditional phase shifts. Thus quantum geometrical
phases can form the basis of any quantum computation. Moreover, as the induced
conditional phase depends only on the geometry of the paths executed by the
spins it is resilient to certain types of errors and offers the potential of a
naturally fault-tolerant way of performing quantum computation.

</DOC>
<DOC>
<DOCNO> 178868 </DOCNO>
Total 4He Photoabsorption Cross Section Revisited: Correlated HH versus


  Two conceptually different hyperspherical harmonics expansions are used for
the calculation of the total 4He photoabsorption cross section. Besides the
well known method of CHH the recently introduced effective interaction approach
for the hyperspherical formalism is applied. Semi-realistic NN potentials are
employed and final state interaction is fully taken into account via the
Lorentz integral transform method. The results show that the effective
interaction leads to a very good convergence, while the correlation method
exhibits a less rapid convergence in the giant dipole resonance region. The
rather strong discrepancy with the experimental photodisintegration cross
sections is confirmed by the present calculations.

</DOC>
<DOC>
<DOCNO> 150319 </DOCNO>
BPS states of D=4 N=1 supersymmetry


  We find the combinations of momentum and domain-wall charges corresponding to
BPS states preserving 1/4, 1/2 or 3/4 of D=4 N=1 supersymmetry, and we show how
the supersymmetry algebra implies their stability. These states form the
boundary of the convex cone associated with the Jordan algebra of $4\times 4$
real symmetric matrices, and we explore some implications of the associated
geometry. For the Wess-Zumino model we derive the conditions for preservation
of 1/4 supersymmetry when one of two parallel domain-walls is rotated and in
addition show that this model does not admit any classical configurations with
3/4 supersymmetry. Our analysis also provides information about BPS states of
N=1 D=4 anti-de Sitter supersymmetry.

</DOC>
<DOC>
<DOCNO> 67895 </DOCNO>
Quantum electrodynamics of composite fermions


  The quantum Dirac-like equation and the QED vertex operator for a composite
particle are suggested. The vertex operator and the fermionic propagator are
connected by the QED Ward identity. It is shown that all of the Feynman
QED-integrals for a three-component particle are finite with some suggestion
about large momentum dependence of the vertex operator. This dependence is in
agreement with the component counting rules.

</DOC>
<DOC>
<DOCNO> 7988 </DOCNO>
Surface collective excitations in ultrafast pump-probe spectroscopy of


  The role of surface collective excitations in the electron relaxation in
small metal particles is studied. It is shown that the dynamically screened
electron-electron interaction in a nanoparticle contains a size-dependent
correction induced by the surface. This leads to new channels of quasiparticle
scattering accompanied by the emission of surface collective excitations. In
noble-metal particles, the dipole collective excitations (surface plasmons)
mediate a resonant scattering of d-holes to the conduction band. The role of
this effect in the ultrafast optical dynamics of small nanoparticles is
studied. With decreasing nanoparticle size, it leads to a strong change in the
differential absorption lineshape and a strong frequency dependence of the
relaxation near the surface plasmon resonance. The experimental implications of
these results in ultrafast pump-probe spectroscopy are addressed. The
size-dependence of conduction electron scattering rates is also discussed.

</DOC>
<DOC>
<DOCNO> 99395 </DOCNO>
A remark on the Chisini conjecture


  The Chisini conjecture asserts that a generic ramified covering over the
complex projective plane of degree at least 5 is uniquely determined by its
branch curve. We prove this for degree at least 12 using the work of Kulikov
(math-AG/9803144).

</DOC>
<DOC>
<DOCNO> 169634 </DOCNO>
Quantum Computation by Adiabatic Evolution


  We give a quantum algorithm for solving instances of the satisfiability
problem, based on adiabatic evolution. The evolution of the quantum state is
governed by a time-dependent Hamiltonian that interpolates between an initial
Hamiltonian, whose ground state is easy to construct, and a final Hamiltonian,
whose ground state encodes the satisfying assignment. To ensure that the system
evolves to the desired final ground state, the evolution time must be big
enough. The time required depends on the minimum energy difference between the
two lowest states of the interpolating Hamiltonian. We are unable to estimate
this gap in general. We give some special symmetric cases of the satisfiability
problem where the symmetry allows us to estimate the gap and we show that, in
these cases, our algorithm runs in polynomial time.

</DOC>
<DOC>
<DOCNO> 7918 </DOCNO>
Q-Factor Measurement of Nonlinear Superconducting Resonators


  A novel method, which combined a multi-bandwidth measurement and an
extrapolation procedure, is proposed for extracting the loaded Q-factor (Q_{L})
with improved accuracy from non-Lorentzian resonances of nonlinear
superconducting resonators.

</DOC>
<DOC>
<DOCNO> 11231 </DOCNO>
Statistics of resonances and of delay times in quasiperiodic


  We study the statistical distributions of the resonance widths ${\cal P}
(\Gamma)$, and of delay times ${\cal P} (\tau)$ in one dimensional
quasi-periodic tight-binding systems with one open channel. Both quantities are
found to decay algebraically as $\Gamma^{-\alpha}$, and $\tau^{-\gamma}$ on
small and large scales respectively. The exponents $\alpha$, and $\gamma$ are
related to the fractal dimension $D_0^E$ of the spectrum of the closed system
as $\alpha=1+D_0^E$ and $\gamma=2-D_0^E$. Our results are verified for the
Harper model at the metal-insulator transition and for Fibonacci lattices.

</DOC>
<DOC>
<DOCNO> 69357 </DOCNO>
CP Violation from Supersymmetry in Hyperon Decays


  We point out that in supersymmetric models the direct CP violating asymmetry
$A(\Lambda^0_-)$ in $\Lambda \to \pi^- p$ can be of $O(10^{-3})$ in the range
to be probed by the current E871 experiment.

</DOC>
<DOC>
<DOCNO> 70930 </DOCNO>
Parity-violating 3-jet observables for massive quarks to order alphas^2


  In this talk we discuss the calculation of the QCD corrections to
parity-violating 3-jet observables in e^+e^- collisions, keeping the full quark
mass dependence.

</DOC>
<DOC>
<DOCNO> 116591 </DOCNO>
Algebraic Models: Coordinates, Scales, and Dynamical Symmetries


  We discuss the variety of coordinates often used to characterize the coherent
state classical limit of an algebraic model. We show selection of appropriate
coordinates naturally motivates a procedure to generate a single particle
Schr\"odinger hamiltonian which, for low energy states, gives equivalent
results to a bosonic algebraic model to leading order in $N$. The process is
used to study the associated geometries of the dynamical symmetries of U(3). By
demanding that the inner product be preserved in the Schr\"odinger picture we
conclude that different dynamical symmetries correspond to different scales.

</DOC>
<DOC>
<DOCNO> 122351 </DOCNO>
LOWL p-mode frequencies and their variation with solar activity


  We present an analysis of the frequency shift and the even terms of the
frequency splitting coefficients carried out using six years of LOWL data,
starting in 1994. The temporal variations, and their dependences with the
frequency and degree are addressed. The results are consistent with previous
analysis.

</DOC>
<DOC>
<DOCNO> 119617 </DOCNO>
Search for the Identification of 3EG J1835+5918: Evidence for a New Type


  The EGRET source 3EG J1835+5918 is the brightest and most accurately
positioned of the as-yet unidentified high-energy gamma-ray sources at high
Galactic latitude (l,b=89,25). We present a multiwavelength study of the region
around it, including X-ray, radio, and optical imaging surveys, as well as
optical spectroscopic classification of most of the active objects in this
area. The identified X-ray sources in or near the EGRET error ellipse are
radio-quiet QSOs, a galaxy cluster, and coronal emitting stars. The radio
sources inside the error ellipse are all fainter than 4 mJy at 1.4 GHz. In
addition there are no flat-spectrum radio sources in the vicinity. Since no
blazar-like or pulsar-like candidate has been found as a result of these
searches, 3EG J1835+5918 must be lacking one or more of the physically
essential attributes of these known classes of gamma-ray emitters. If it is an
AGN it lacks the beamed radio emission of blazars by at least a factor of 100
relative to identified EGRET blazars. If it is an isolated neutron star, it
lacks the steady thermal X-rays from a cooling surface and the magnetospheric
non-thermal X-ray emission that is characteristic of all EGRET pulsars. If a
pulsar, 3EG J1835+5918 must be either older or more distant than Geminga, and
probably an even more efficient or beamed gamma-ray engine.

</DOC>
<DOC>
<DOCNO> 69757 </DOCNO>
Computation of $\bar{\Lambda}$ and $\lambda_1$ with Lattice QCD


  We pursue a new method, based on lattice QCD, for determining the quantities
$\bar{\Lambda}$, $\lambda_1$, and $\lambda_2$ of heavy-quark effective theory.
We combine Monte Carlo data for the meson mass spectrum with perturbative
calculations of the short-distance behavior, to extract $\bar{\Lambda}$ and
$\lambda_1$ from a formula from HQET. Taking into account uncertainties from
fitting the mass dependence and from taking the continuum limit, we find
$\bar{\Lambda} = 0.68{+0.02}_{-0.12} \text{GeV}$ and $\lambda_1 = -(0.45 \pm
0.12) \text{GeV}^2$ in the quenched approximation.

</DOC>
<DOC>
<DOCNO> 83380 </DOCNO>
Modeling Ambiguity in a Multi-Agent System


  This paper investigates the formal pragmatics of ambiguous expressions by
modeling ambiguity in a multi-agent system. Such a framework allows us to give
a more refined notion of the kind of information that is conveyed by ambiguous
expressions. We analyze how ambiguity affects the knowledge of the dialog
participants and, especially, what they know about each other after an
ambiguous sentence has been uttered. The agents communicate with each other by
means of a TELL-function, whose application is constrained by an implementation
of some of Grice's maxims. The information states of the multi-agent system
itself are represented as a Kripke structures and TELL is an update function on
those structures. This framework enables us to distinguish between the
information conveyed by ambiguous sentences vs. the information conveyed by
disjunctions, and between semantic ambiguity vs. perceived ambiguity.

</DOC>
<DOC>
<DOCNO> 101460 </DOCNO>
AF flows and continuous symmetries


  We consider AF-flows, i.e., one-parameter automorphism groups of a unital
simple C*-algebra which leave invariant the dense union of an increasing
sequence of finite-dimensional *-subalgebras, and derive two properties for
these; an absence of continuous symmetry breaking and a kind of real rank zero
property for the almost fixed points.

</DOC>
<DOC>
<DOCNO> 121224 </DOCNO>
Iron Abundance Profiles of 12 Clusters of Galaxies Observed With


  We have derived azimuthally-averaged radial iron abundance profiles of the
X-ray gas contained within 12 clusters of galaxies with redshift 0.03 < z < 0.2
observed with BeppoSAX. We find evidence for a negative metal abundance
gradient in most of the clusters, particularly significant in clusters that
possess cooling flows. The composite profile from the 12 clusters resembles
that of cluster simulations of Metzler & Evrard (1997). This abundance gradient
could be the result of the spatial distribution of gas-losing galaxies within
the cluster being more centrally condensed than the primordial hot gas. Both
inside and outside the core region, we find a higher abundance in cooling flow
clusters than in non-cooling flow clusters. Outside of the cooling region this
difference cannot be the result of more efficient sputtering of metals into the
gaseous phase in cooling flow clusters, but might be the result of the mixing
of low metallicity gas from the outer regions of the cluster during a merger.

</DOC>
<DOC>
<DOCNO> 14051 </DOCNO>
Spin-stiffness and topological defects in two-dimensional frustrated


  Using a {\it collective} Monte Carlo algorithm we study the low-temperature
and long-distance properties of two systems of two-dimensional classical tops.
Both systems have the same spin-wave dynamics (low-temperature behavior) as a
large class of Heisenberg frustrated spin systems. They are constructed so that
to differ only by their topological properties. The spin-stiffnesses for the
two systems of tops are calculated for different temperatures and different
sizes of the sample. This allows to investigate the role of topological defects
in frustrated spin systems. Comparisons with Renormalization Group results
based on a Non Linear Sigma model approach and with the predictions of some
simple phenomenological model taking into account the topological excitations
are done.

</DOC>
<DOC>
<DOCNO> 170538 </DOCNO>
Photon-photon correlations and entanglement in doped photonic crystals


  We consider a photonic crystal (PC) doped with four-level atoms whose
intermediate transition is coupled near-resonantly with a photonic band-gap
edge. We show that two photons, each coupled to a different atomic transition
in such atoms, can manifest strong phase or amplitude correlations: One photon
can induce a large phase shift on the other photon or trigger its absorption
and thus operate as an ultrasensitive nonlinear photon-switch. These features
allow the creation of entangled two-photon states and have unique advantages
over previously considered media: (i) no control lasers are needed; (ii) the
system parameters can be chosen to cause full two-photon entanglement via
absorption; (iii) a number of PCs can be combined in a network.

</DOC>
<DOC>
<DOCNO> 101292 </DOCNO>
Bethe Equation at q=0, Moebius Inversion Formula, and Weight


  We study a family of power series characterized by a system of recursion
relations (Q-system) with a certain convergence property. We show that the
coefficients of the series are expressed by the numbers which formally count
the off-diagonal solutions of the U_q(X^{(1)}_n) Bethe equation at q=0. The
series are conjectured to be the X_n-character of a certain family of
irreducible finite-dimensional U_q(X^{(1)}_n) -modules which we call the KR
(Kirillov-Reshetikhin) modules. Under the above conjecture, these coefficients
give a formula of the weight multiplicities of the tensor products of the KR
modules, which is also interpreted as the formal completeness of the XXZ-type
Bethe vectors.

</DOC>
<DOC>
<DOCNO> 169585 </DOCNO>
Spin dynamics of wave packets evolving with the Dirac Hamiltonian in


  The motion of circular WP for one electron in central Coulomb field with high
Z is calculated. The WP is defined in terms of solutions of the Dirac equation
in order to take into account all possible relevant effects in particular the
spin-orbit potential. A time scale is defined within which spin dynamics must
be taken into account mainly in the atoms with high Z. Within this time scale
there exists a mechanism of collapses and revivals of the spin already shown by
the authors for harmonic oscillator potential and called the 'spin-orbit
pendulum'. However this effect has not the exact periodicity of the simpler
model, but the WP's spatial motion is nevertheless quite similar.

</DOC>
<DOC>
<DOCNO> 8958 </DOCNO>
Effective potentials for 6-coordinated Boron: structural geometry


  We have built a database of ab-initio total energies for elemental Boron in
over 60 hypothetical crystal structures of varying coordination $Z$, such that
every atom is equivalent. Fitting to each subset with a particular $Z$, we
extract a classical effective potential, written as a sum over coordination
shells and dominated by three-atom (bond angle dependent) terms. In the case
Z=6 (lowest in energy and most relevant), the classical potential has a typical
error of 0.1 eV/atom, and favours the ``inverted-umbrells'' environment seen in
real Boron.

</DOC>
<DOC>
<DOCNO> 67983 </DOCNO>
Bose Symmetry Interference Effects of $4\pi$ Final States


  We carefully analyze the relative branching ratios of $4\pi$ final states
$\pi^+\pi^-\pi^+\pi^-$, $\pi^+\pi^-\pi^0\pi^0$ and $\pi^0\pi^0\pi^0\pi^0$, from
various resonances of $J^{PC}=0^{++}$, $0^{-+}$, $2^{++}$. We find that the
Bose symmetry interference effects would make their ratios to obviously differ
from the naive counting values without considering these effects. The results
should be applied to estimate correctly various $4\pi$ decay branching ratios
of relevant resonances.

</DOC>
<DOC>
<DOCNO> 71456 </DOCNO>
Particle interferometry, binary sources and oscillations in two-particle


  The basics and the formalism of Bose-Einstein correlations is briefly
reviewed. The invariant Buda-Lund form is summarized. Tools are presented that
can be utilized in a model-independent search for non-Gaussian structuctures in
the two-particle Bose-Einstein correlation functions. The binary source
formalism of particle interferometry is presented and related to oscillations
in the two-particle Bose-Einstein and Fermi-Dirac correlation functions. The
frequency of the observed oscillations in the NA49 two-proton correlation
function in Pb+Pb collisions at CERN SPS energies is explained with the help of
the reconstructed space-time picture of particle production and the binary
nature of the proton source in this reaction.

</DOC>
<DOC>
<DOCNO> 84471 </DOCNO>
Supersymmetric Brane-Worlds


  We present warped metrics which solve Einstein equations with arbitrary
cosmological constants in both in upper and lower dimensions. When the
lower-dimensional metric is the maximally symmetric one compatible with the
chosen value of the cosmological constant, the upper-dimensional metric is also
the maximally symmetric one and there is maximal unbroken supersymmetry as
well. We then introduce brane sources and find solutions with analogous
properties, except for supersymmetry, which is generically broken in the
orbifolding procedure (one half is preserved in two special cases), and analyze
metric perturbations in these backgrounds In analogy with the D8-brane we
propose an effective $(\hat{d}-2)$-brane action which acts as a source for the
RS solution. The action consists of a Nambu-Goto piece and a Wess-Zumino term
containing a $(\hat{d}-1)$-form field. It has the standard form of the action
for a BPS extended object, in correspondence with the supersymmetry preserved
by the solution.

</DOC>
<DOC>
<DOCNO> 85632 </DOCNO>
Thermodynamics of Near-Extreme Black Holes


  The thermodynamics of nearly-extreme charged black holes depends upon the
number of ground states at fixed large charge and upon the distribution of
excited energy states. Here three possibilities are examined: (1) Ground state
highly degenerate (as suggested by the large semiclassical Hawking entropy of
an extreme Reissner-Nordstrom black hole), excited states not. (2) All energy
levels highly degenerate, with macroscopic energy gaps between them. (3) All
states nondegenerate (or with low degeneracy), separated by exponentially tiny
energy gaps. I suggest that in our world with broken supersymmetry, this last
possibility seems most plausible. An experiment is proposed to distinguish
between these possibilities, but it would take a time that is here calculated
to be more than about 10^837 years.

</DOC>
<DOC>
<DOCNO> 151494 </DOCNO>
On D-branes from Gauged Linear Sigma Models


  We study both A-type and B-type D-branes in the gauged linear sigma model by
considering worldsheets with boundary. The boundary conditions on the matter
and vector multiplet fields are first considered in the large-volume
phase/non-linear sigma model limit of the corresponding Calabi-Yau manifold,
where we also find that we need to add a contact term on the boundary. These
considerations enable to us to derive the boundary conditions in the full
gauged linear sigma model, including the addition of the appropriate boundary
contact terms, such that these boundary conditions have the correct non-linear
sigma model limit. Most of the analysis is for the case of Calabi-Yau manifolds
with one Kahler modulus (including those corresponding to hypersurfaces in
weighted projective space), though we comment on possible generalizations.

</DOC>
<DOC>
<DOCNO> 119315 </DOCNO>
UV excess galaxies: Wolf-Rayet galaxies


  We discuss V and R band photometry for 67% of the Sullivan et al. 2000 SA57
ultraviolet-selected galaxy sample. In a sample of 176 UV-selected galaxies,
Sullivan et al. 2000 find that 24% have (UV-B) colors too blue for consistency
with starburst spectral synthesis models. We propose that these extreme blue,
UV excess galaxies are Wolf-Rayet (WR) galaxies, starburst galaxies with strong
UV emission from WR stars. We measure a median (V-R)=0.38+-0.06 for the
UV-selected sample, bluer than a sample optically selected at R but consistent
with starburst and WR galaxy colors. We demonstrate that redshifted WR emission
lines can double or triple the flux through the UV bandpass at high redshifts.
Thus the (UV-B) color of a WR galaxy can be up to 1.3 mag bluer at high
redshift, and the expected selection function is skewed to larger redshifts.
The redshift distribution of the extreme blue, UV excess galaxies matches the
selection function we predict from the properties of WR galaxies.

</DOC>
<DOC>
<DOCNO> 10669 </DOCNO>
Vortex states in binary mixture of Bose-Einstein condensates


  The vortex configurations in the Bose-Einstein condensate of the mixture of
two different spin states |F=1,m_f=-1> and |2,1> of ^{87}Rb atoms corresponding
to the recent experiments by Matthews et. al. (Phys. Rev. Lett. 83, 2498
(1999)) are considered in the framework of the Thomas-Fermi approximation as
functions of N_2/N_1, where N_1 is the number of atoms in the state |1,-1> and
N_2 - in the state |2,1>. It is shown that for nonrotating condensates the
configuration with the |1,-1> fluid forming the shell about the |2,1> fluid
(configuration "a") has lower energy than the opposite configuration
(configuration "b") for all values of N_2/N_1. When the |1,-1> fluid has net
angular momentum and forms an equatorial ring around the resting central
condensate |2,1>, the total energy of the system is higher than the ground
energy, but the configuration "a" has lower energy than the configuration "b"
for all N_2/N_1. On the other hand, when the |2> fluid has the net angular
momentum, for the lowest value of the angular momentum \hbar l (l=1) there is
the range of the ratio N_2/N_1 where the configuration "b" has lower energy
than the configuration "a". For higher values of the angular momentum the
configuration "b" is stable for all values of N_2/N_1.

</DOC>
<DOC>
<DOCNO> 152376 </DOCNO>
Splitting of Heterogeneous Boundaries in a System of the Tricritical


  We study disk amplitudes whose boundaries have heterogeneous matter states in
a system of $(4,5)$ conformal matter coupled to 2-dim gravity. They are
analysed by using the 3-matrix chain model in the large $N$ limit. Each of the
boundaries is composed of two or three parts with distinct matter states. From
the obtained amplitudes, it turns out that each heterogeneous boundary loop
splits into several loops and we can observe properties in the splitting
phenomena that are common to each of them. We also discuss the relation to
boundary operators.

</DOC>
<DOC>
<DOCNO> 11391 </DOCNO>
Oscillatory Electron-Phonon Coupling in Ultra-Thin Silver Films on


  The temperature dependence of peak widths in high resolution angle-resolved
photoelectron spectroscopy from quantum well states in ultra thin Ag films on
V(100) has been used to determine the electron-phonon coupling constant,
lambda, for films of thickness 1-8 layers. A strong oscillatory variation in
coupling strength is observed as a function of film thickness, peaking at a 2
layer film for which lambda~1. A simple theory incorporating interaction of the
photo-hole with the thermal vibrations of the potential step at the
adlayer-vacuum interface is shown to reproduce the main features of these
results.

</DOC>
<DOC>
<DOCNO> 13405 </DOCNO>
Solving large nonlinear generalized eigenvalue problems from Density


  The quantum mechanical ground state of electrons is described by Density
Functional Theory, which leads to large minimization problems. An efficient
minimization method uses a selfconsistent field (SCF) solution of large
eigenvalue problems. The iterative Davidson algorithm is often used, and we
propose a new algorithm of this kind which is well suited for the SCF method,
since the accuracy of the eigensolution is gradually improved along with the
outer SCF-iterations. Best efficiency is obtained for small-block-size
iterations, and the algorithm is highly memory efficient. The implementation
works well on both serial and parallel computers, and good scalability of the
algorithm is obtained.

</DOC>
<DOC>
<DOCNO> 72021 </DOCNO>
Matter-antimatter domains in the universe


  A possible existence of cosmologically large domains of antimatter or
astronomical ``anti-objects'' is discussed. A brief review of different
scenarios of baryogenesis predicting a noticeable amount of antimatter is
given. Though both theory and observations indicate that the universe is most
possibly uniformly charge asymmetric without any noticeable amount of
antimatter, several natural scenarios are possible that allow for
cosmologically (astronomically) interesting objects in close vicinity to us.
The latter may be discovered by observation of cosmic ray antinuclei.

</DOC>
<DOC>
<DOCNO> 11089 </DOCNO>
Dielectric function of aggregates of small metallic particles embedded


  The optical properties of clusters with metallic spherical particles embedded
in an insulating matrix are studied. A theoretical approach is proposed for the
calculation of the macroscopic dielectric response for a collection of spheres
at random positions embedded in a homogeneous medium. While accounting for the
dipole interaction between particles, we have considered the frequency
dependence behavior of the imaginary part of the effective dielectric constant
in this system with two kinds of particles of different sizes.

</DOC>
<DOC>
<DOCNO> 84106 </DOCNO>
Predicting Future Duration from Present Age: A Critical Assessment


  Using a temporal version of the Copernican principle, Gott has proposed a
statistical predictor of future longevity based on present age [J. R. Gott III,
Nature 363, 315 (1993)] and applied the predictor to a variety of examples,
including the longevity of the human species. Though Gott's proposal contains a
grain of truth, it does not have the universal predictive power that he
attributes to it.

</DOC>
<DOC>
<DOCNO> 118932 </DOCNO>
Near/Mid Infrared-Wavelength Study of the Interacting Galaxy Pair UGC


  We report on an infrared 1 to 17 micron study of the nearby (cz = 4600 km/s)
interacting spiral galaxy system, UGC 12914/12915, using the ground-based
Palomar 200" telescope and PFIRCAM near-infrared detector and space-based
mid-infrared imaging and spectral observations using ISOCAM and Phot-S on the
Infrared Space Observatory (ISO). Strong line emission from aromatic band
features at 6.2, 7.7 and 11.3 microns are seen in both the mid-IR imaging and
Phot-S spectro-photometry centered on the nuclei. In the connecting bridge, the
mid-infrared imaging reveals dust grains intermixed with the atomic hydrogen
gas. The heating mechanism for the hot dust is likely to be UV photons
diffusing out from the galactic disks and the H II complex located along the
extreme northeastern portion of the bridge: The dust emission, or mid-infrared
intensity per atomic hydrogen column density ratio, is consistent with heating
from the local (bridge) interstellar radiation field.

</DOC>
<DOC>
<DOCNO> 151252 </DOCNO>
A Simple Volcano Potential with an Analytic, Zero-Energy, Ground State


  We describe a simple volcano potential, which is supersymmetric and has an
analytic, zero-energy, ground state. (The KK modes are also analytic.) It is an
interior harmonic oscillator potential properly matched to an exterior angular
momentum-like tail. Special cases are given to elucidate the physics, which may
be intuitively useful in studies of higher-dimensional gravity.

</DOC>
<DOC>
<DOCNO> 121742 </DOCNO>
Gas Dynamics in Galaxy Mergers


  In interacting and merging galaxies, gas is subject to direct hydrodynamic
effects as well as tidal forces. One consequence of interactions is the rapid
inflows of gas which may fuel starbursts and AGN. But gas dynamics is not
limited to inflows; a small survey of equal-mass and unequal-mass encounters
produces a wide variety of features, including plumes between galaxies,
extended disks formed by infall of tidal debris, and counterrotating nuclear
disks. An even richer spectrum of behavior awaits better thermodynamic models
for gas in merging galaxies.

</DOC>
<DOC>
<DOCNO> 123100 </DOCNO>
Spectroscopy and Imaging Performance of the Liquid Xenon Gamma-Ray


  LXeGRIT is a balloon-borne Compton telescope based on a liquid xenon time
projection chamber (LXeTPC) for imaging cosmic \g-rays in the energy band of
0.2-20 MeV. The detector, with 400 cm$^2$ area and 7 cm drift gap, is filled
with high purity LXe. Both ionization and scintillation light signals are
detected to measure the energy deposits and the three spatial coordinates of
individual \g -ray interactions within the sensitive volume. The TPC has been
characterized with repeated measurements of its spectral and Compton imaging
response to \g -rays from radioactive sources such as \na, \cs, \yt and Am-Be.
The detector shows a linear response to \g -rays in the energy range 511 keV
-4.4 MeV, with an energy resolution (FWHM) of $ \Delta E/E=8.8% \: \sqrt{1\MeV
/E}$. Compton imaging of \yt \g -ray events with two detected interactions is
consistent with an angular resolution of $\sim$ 3 degrees (RMS) at 1.8 MeV.

</DOC>
<DOC>
<DOCNO> 11428 </DOCNO>
Phase Transitions in one-dimensional nonequilibrium systems


  The phenomenon of phase transitions in one-dimensional systems is discussed.
Equilibrium systems are reviewed and some properties of an energy function
which may allow phase transitions and phase ordering in one dimension are
identified. We then give an overview of the one-dimensional phase transitions
which we have been studied in nonequilibrium systems. A particularly simple
model, the zero-range process, for which the steady state is know exactly as a
product measure, is discussed in some detail. Generalisations of the model, for
which a product measure still holds, are also discussed. We analyse in detail a
condensation phase transition in the model and show how conditions under which
it may occur may be related to the existence of an effective long-range energy
function. Although the zero-range process is not well known within the physics
community, several nonequilibrium models have been proposed that are examples
of a zero-range process, or closely related to it, and we review these
applications here.

</DOC>
<DOC>
<DOCNO> 120034 </DOCNO>
Monte Carlo Simulations of Type Ia Supernova Observations in Supernova


  We have performed Monte Carlo simulations of type Ia supernova (SN Ia)
surveys to quantify their efficiency in discovering peculiar overluminous and
underluminous SNe Ia. We determined how the type of survey (magnitude-limited,
distance-limited, or a hybrid) and its characteristics (observations frequency
and detection limit) affect the discovery of peculiar SNe Ia. We find that
there are strong biases against the discovery of peculiar SNe Ia introduced by
at least four observational effects: the Malmquist bias, the age of the SN Ia
at the time of its discovery, the shape of its light curve, and its degree of
extinction. Surveys with low observation frequency (less than once per 10 days)
tend to discover SNe Ia which are too old for observers to easily recognize
their peculi arity. Subluminous SNe Ia are underrepresented in
magnitude-limited surveys because they can only be found within a small volume
and they remain above the detection limit for less time. Conversely,
overluminous SNe Ia are more easily found in magnitude-limited surveys although
their likely association with dusty regions reduces the volume in which they
can be discovered. The unbiased rate of peculiar SNe Ia can be recovered only
in distance-limited surveys with high observation frequencies and with
detection limits which are fainter than the peak magnitude of a subluminous SN
Ia in the farthest potential host.

</DOC>
<DOC>
<DOCNO> 120668 </DOCNO>
SN 1984A and Delayed Detonation Models of Type Ia Supernovae


  SN 1984A shows unusually large expansion velocities in lines from freshly
synthesized material, relative to typical Type Ia Supernovae (SNe Ia). SN 1984A
is an example of a group of SNe Ia which have very large blue-shifts of the
P-Cygni features, but otherwise normal spectra. We have modeled several early
spectra of SN 1984A with the multi-purpose NLTE model atmosphere and spectrum
synthesis code, PHOENIX. We have used as input two delayed detonation models:
CS15DD3 (Iwamoto et al. 1999) and DD21c (Hoeflich, Wheeler & Thielemann 1998).
These models show line expansion velocities which are larger than that for a
typical deflagration model like W7, which we have previously shown to fit the
spectra of normal SNe Ia quite well. We find these delayed detonation models to
be reasonable approximations to large absorption feature blue-shift SNe Ia,
like SN 1984A. Higher densities of newly synthesized intermediate mass elements
at higher velocities, v > 15,000 km/s, are found in delayed detonation models
than in deflagration models. We find that this increase in density at high
velocities is responsible for the larger blue-shifts in the synthetic spectra.
We show that the variations in line width in observed SNe Ia are likely due to
density variations in the outer, high-velocity layers of their atmospheres.

</DOC>
<DOC>
<DOCNO> 120934 </DOCNO>
Star Formation History in the Nicmos Northern Hubble Deep Field


  This paper presents the star formation history in the NICMOS Northern Deep
HDF. It uses the techniques of photometric redshifts and extinctions to correct
for extinction of the ultra-violet flux. It presents a new method for
correcting for surface brightness diming. It also predicts the 850 micron
fluxes of the objects for comparison with SCUBA measurements

</DOC>
<DOC>
<DOCNO> 117673 </DOCNO>
Best Unbiased Estimators for the Three-Point Correlators of the Cosmic


  Measuring the three-point correlators of the Cosmic Microwave Background
(CMB) anisotropies could help to get a handle on the level of non-Gaussianity
present in the observational datasets and therefore would strongly constrain
models of the early Universe. However, typically, the expected non-Gaussian
signal is very small. Therefore, one has to face the problem of extracting it
from the noise, in particular from the `cosmic variance' noise. For this
purpose, one has to construct the best unbiased estimators for the three-point
correlators that are needed for concrete detections of non-Gaussian features.
In this article, we study this problem for both the CMB third moment and the
CMB angular bispectrum. We emphasize that the knowledge of the best estimator
for the former does not permit one to infer the best estimator for the latter
and vice versa. We present the corresponding best unbiased estimators in both
cases and compute their corresponding cosmic variances.

</DOC>
<DOC>
<DOCNO> 85519 </DOCNO>
Regularity and stability of electrostatic solutions in Kaluza-Klein


  We investigate the family of electrostatic spherically symmetric solutions of
the five-dimensional Kaluza-Klein theory. Besides black holes and wormholes, a
new class of geodesically complete solutions is identified. A monopole
perturbation is carried out, enabling us to prove analytically the stability of
a large class of solutions, including all black holes and neutral solutions.

</DOC>
<DOC>
<DOCNO> 69039 </DOCNO>
Metastable States of a Coupled Pair on a Repulsive Barrier


  Resonance penetration of two coupled particles through a repulsive barrier is
considered. It is shown that a local minimum of the total potential generates
metastable bound states, and their spectrum determines the position of
resonances in the penetration probability. It is pointed out that the
probabilities of tunneling of two interacting particles from the false vacuum
can be essentially higher than it has been assumed earlier.

</DOC>
<DOC>
<DOCNO> 170636 </DOCNO>
Efficient Quantum Key Distribution Scheme And Proof of Its Unconditional


  We devise a simple modification that essentially doubles the efficiency of
the BB84 quantum key distribution scheme proposed by Bennett and Brassard. We
also prove the security of our modified scheme against the most general
eavesdropping attack that is allowed by the laws of physics. The first major
ingredient of our scheme is the assignment of significantly different
probabilities to the different polarization bases during both transmission and
reception, thus reducing the fraction of discarded data. A second major
ingredient of our scheme is a refined analysis of accepted data: We separate
the accepted data into various subsets according to the basis employed and
estimate an error rate for each subset separately. We then show that such a
refined data analysis guarantees the security of our scheme against the most
general eavesdropping strategy, thus generalizing Shor and Preskill's proof of
security of BB84 to our new scheme. Up till now, most proposed proofs of
security of single-particle type quantum key distribution schemes have relied
heavily upon the fact that the bases are chosen uniformly, randomly and
independently. Our proof removes this symmetry requirement.

</DOC>
<DOC>
<DOCNO> 123119 </DOCNO>
Discovery of a Transient Absorption Edge in the X-ray Spectrum of GRB


  We report the discovery of a transient equivalent hydrogen column density
with an absorption edge at ~3.8 kiloelectron volts in the spectrum of the
prompt x-ray emission of gamma-ray burst (GRB) 990705. This feature can be
satisfactorily modeled with a photoelectric absorption by a medium located at a
redshift of ~0.86 and with an iron abundance of ~75 times the solar one. The
transient behavior is attributed to the strong ionization produced in the
circumburst medium by the GRB photons. The high iron abundance points to the
existence of a burst environment enriched by a supernova along the line of
sight. The supernova explosion is estimated to have occurred about 10 years
before the burst. Our results agree with models in which GRBs originate from
the collapse of very massive stars and are preceded by a supernova event

</DOC>
<DOC>
<DOCNO> 178939 </DOCNO>
Parity-Violating Electron-Deuteron Scattering


  The longitudinal asymmetry due to $Z^0$ exchange is calculated in
quasi-elastic electron-deuteron scattering at momentum transfers $|Q^2| \simeq
0.1$ GeV$^2$ relevant for the SAMPLE experiment. The deuteron and $pn$
scattering-state wave functions are obtained from solutions of a Schr\"odinger
equation with the Argonne $v_{18}$ potential. Electromagnetic and weak neutral
one- and two-nucleon currents are included in the calculation. The two-nucleon
currents of pion range are shown to be identical to those derived in Chiral
Perturbation Theory. The results indicate that two-body contributions to the
asymmetry are small ($\simeq$ 0.2%) around the quasi-elastic peak, but become
relatively more significant ($\simeq$ 3%) in the high-energy wing of the
quasi-elastic peak.

</DOC>
<DOC>
<DOCNO> 101601 </DOCNO>
A simple maximality principle


  In this paper, following an idea of Christophe Chalons, I propose a new kind
of forcing axiom, the Maximality Principle, which asserts that any sentence phi
holding in some forcing extension V^P and all subsequent extensions V^P*Q holds
already in V. It follows, in fact, that such sentences must also hold in all
forcing extensions of V. In modal terms, therefore, the Maximality Principle is
expressed by the scheme (diamond box phi) implies (box phi), and is equivalent
to the modal theory S5. In this article, I prove that the Maximality Principle
is relatively consistent with ZFC. A boldface version of the Maximality
Principle, obtained by allowing real parameters to appear in phi, is
equiconsistent with the scheme asserting that V_delta is an elementary
substructure of V for an inaccessible cardinal delta, which in turn is
equiconsistent with the scheme asserting that ORD is Mahlo. The strongest
principle along these lines is the Necessary Maximality Principle, which
asserts that the boldface MP holds in V and all forcing extensions. From this,
it follows that 0# exists, that x# exists for every set x, that projective
truth is invariant by forcing, that Woodin cardinals are consistent and much
more. Many open questions remain.

</DOC>
<DOC>
<DOCNO> 80774 </DOCNO>
Eigenvalue Distributions of the QCD Dirac Operator


  We compute by Monte Carlo methods the individual distributions of the $k$th
smallest Dirac operator eigenvalues in QCD, and compare them with recent
analytical predictions. We do this for both massless and massive quarks in an
SU(3) gauge theory with staggered fermions. Very precise agreement is found in
all cases. As a simple by-product we also extract the microscopic spectral
density of the Dirac operator in SU(3) gauge theory with dynamical massive
fermions for $N_f=1$ and 2, and obtain high-accuracy agreement with analytical
expressions.

</DOC>
<DOC>
<DOCNO> 117988 </DOCNO>
Evolution of Lyman Break Galaxies Beyond Redshift Four


  The formation rate of luminous galaxies seems to be roughly constant from z~2
to z~4 from the recent observations of Lyman break galaxies (LBGs) (Steidel et
al 1999). The abundance of luminous quasars, on the other hand, appears to drop
off by a factor of more than twenty from z~2 to z~5 (Warren, Hewett, & Osmer
1994; Schmidt, Schneider, & Gunn 1995). The difference in evolution between
these two classes of objects in the overlapping, observed redshift range,
z=2-4, can be explained naturally, if we assume that quasar activity is
triggered by mergers of luminous LBGs and one quasar lifetime is ~10^{7-8} yrs.
If this merger scenario holds at higher redshift, for the evolutions of these
two classes of objects to be consistent at z>4, the formation rate of luminous
LBGs is expected to drop off at least as rapidly as exp(-(z-4)^{6/5}) at z>4.

</DOC>
<DOC>
<DOCNO> 12064 </DOCNO>
Effect of a forbidden site on a d-dimensional lattice random walk


  We study the effect of a single excluded site on the diffusion of a particle
undergoing random walk in a d-dimensional lattice. The determination of the
characteristic function allows to find explicitly the asymptotical behaviour of
physical quantities such as the particle average position (drift) and the mean
square deviation. Contrarily to the one-dimensional case, where the average
coordinate diverges at infinite times as t**1/2 and where the diffusion
constant D is changed due to the impurity, the effects of the latter are shown
to be much less important in higher dimensions: for d=842, the position is
simply shifted by a constant and the diffusion constant remains unaltered
although dynamical corrections (logarithmic for d=2) still occur. Finally, the
continuum space version of the model is analyzed; it is shown that d=1 is the
lower dimensionality above which all the effects of the forbidden site are
irrelevant.

</DOC>
<DOC>
<DOCNO> 101295 </DOCNO>
Regions of linearity, Lusztig cones and canonical basis elements for the


  Let U_q be the quantum group associated to a Lie algebra g of rank n. The
negative part U^- of U has a canonical basis B with favourable properties,
introduced by Kashiwara and Lusztig. The approaches of Kashiwara and Lusztig
lead to a set of alternative parametrizations of the canonical basis, one for
each reduced expression for the longest word in the Weyl group of g. We show
that if g is of type A_4 there are close relationships between the Lusztig
cones, canonical basis elements and the regions of linearity of
reparametrization functions arising from the above parametrizations. A graph
can be defined on the set of simplicial regions of linearity with respect to
adjacency, and we further show that this graph is isomorphic to the graph with
vertices given by the reduced expressions of the longest word of the Weyl group
modulo commutation and edges given by long braid relations.
  Keywords: Quantum group, Lie algebra, Canonical basis, Tight monomials, Weyl
group, Piecewise-linear functions.

</DOC>
<DOC>
<DOCNO> 150876 </DOCNO>
Temperature of D3-branes off extremality


  We discuss non-extremal rotating D3-branes. We solve the wave equation for
scalars in the supergravity background of certain distributions of branes and
compute the absorption coefficients. The form of these coefficients is similar
to the gray-body factors associated with black-hole scattering. They are given
in terms of two different temperature parameters, indicating that fields (open
string modes) do not remain in thermal equilibrium as we move off extremality.
This should shed some light on the origin of the disagreement between the
supergravity and conformal field theory results on the free energy of a system
of non-coincident D-branes.

</DOC>
<DOC>
<DOCNO> 119551 </DOCNO>
Neutron-Capture Elements in the Early Galaxy: Insights from a Large


  New abundances for neutron-capture (n-capture) elements in a large sample of
metal-poor giants from the Bond survey are presented. The spectra were acquired
with the KPNO 4-m echelle and coude feed spectrographs, and have been analyzed
using LTE fine-analysis techniques with both line analysis and spectral
synthesis. Abundances of eight n-capture elements (Sr, Y, Zr, Ba, La, Nd, Eu,
Dy) in 43 stars have been derived from blue (lambda = 4070--4710, R~20,000, S/N
ratio~100-200) echelle spectra and red (lambda = 6100--6180, R~22,000, S/N
ratio~100-200) coude spectra, and the abundance of Ba only has been derived
from the red spectra for an additional 27 stars. Overall, the abundances show
clear evidence for a large star-to-star dispersion in the heavy element-to-iron
ratios. The new data also confirm that at metallicities [Fe/H] <~ --2.4, the
abundance pattern of the heavy (Z >= 56) n-capture elements in most giants is
well-matched to a scaled Solar System r-process nucleosynthesis pattern. The
onset of the main r-process can be seen at [Fe/H] ~ --2.9. Contributions from
the s-process can first be seen in some stars with metallicities as low as
[Fe/H] ~ --2.75, and are present in most stars with metallicities [Fe/H] >
--2.3. The lighter n-capture elements (Sr-Y-Zr) are enhanced relative to the
heavier r-process element abundances. Their production cannot be attributed
solely to any combination of the Solar System r- and main s-processes, but
requires a mixture of material from the r-process and from an additional
n-capture process which can operate at early Galactic time.

</DOC>
<DOC>
<DOCNO> 84931 </DOCNO>
Search for periodic gravitational radiation with the ALLEGRO


  We describe the search for a continuous signal of gravitational radiation
from a rotating neutron star in the data taken by the ALLEGRO gravitational
wave detector in early 1994. Since ALLEGRO is sensitive at frequencies near 1
kHz, only neutron stars with spin periods near 2 ms are potential sources.
There are no known sources of this typ e for ALLEGRO, so we directed the search
towards both the galactic center and the globular clus ter 47 Tucanae. The
analysis puts a constraint of roughly $8 \times 10^{-24}$ at frequencies near 1
kHz on the gravitational strain emitted from pulsar spin-down in either 47
Tucanae or the galactic center.

</DOC>
<DOC>
<DOCNO> 119167 </DOCNO>
Early galaxy evolution from deep wide field star counts. I. The spheroid


  As part of a global analysis of deep star counts to constrain scenarii of
galaxy formation and evolution, we investigate possible links between the
galactic spheroid and the dark matter halo. A wide set of deep star counts at
high and intermediate galactic latitudes is used to determine the large scale
density law of the spheroid. Assuming a power density law, the exponent,
flattening, local density and IMF slope of this population are estimated. The
estimation is checked for robustness against contamination of star counts by
the thick disc population. Contamination effects are derived from a model of
population synthesis under a broad variety of thick disc parameters. The
parameter fit is based on a maximum likelihood criterion. The best fit spheroid
density law has a flattening of 0.76, a power index of 2.44. There is a
significant degeneracy between these two parameters. The data are also
compatible with a slightly less flattened spheroid (c/a = 0.85), in combination
with a larger power index (2.75). A flatter spheroid (c/a = 0.6) with a power
index of 2 is not excluded either. We also constrain the spheroid IMF slope
\alpha to be 1.9 +/- 0.2, leading to a local density of 1.64 10$^{-4}$ stars
pc$^{-3}$ and a mass density of 4.15 10$^{-5}$ \Msun pc$^{-3}$. With this slope
the expected mass density of brown dwarfs in the halo makes a negligible part
of the dark matter halo, as already estimated from microlensing surveys.
  So, as star count data progresses in depth and extent, the picture of the
spheroid star population that comes out points to a shape quite compatible with
what we know about the distribution of baryonic dark matter if it is made of
stellar remnants, suggesting a common dynamical origin.

</DOC>
<DOC>
<DOCNO> 10569 </DOCNO>
Field theory of absorbing phase transitions with a non-diffusive


  We investigate the critical behavior of a reaction-diffusion system
exhibiting a continuous absorbing-state phase transition. The
reaction-diffusion system strictly conserves the total density of particles,
represented as a non-diffusive conserved field, and allows an infinite number
of absorbing configurations. Numerical results show that it belongs to a wide
universality class that also includes stochastic sandpile models. We derive
microscopically the field theory representing this universality class.

</DOC>
<DOC>
<DOCNO> 84542 </DOCNO>
Exact radiative spacetimes: some recent developments


  Five classes of radiative solutions of Einstein's field equations are
discussed in the light of some new developments. These are plane waves and
their collisions, cylindrical waves, Robinson-Trautman and type N spacetimes,
boost-rotation symmetric spacetimes and generalized Gowdy-type cosmological
models

</DOC>
<DOC>
<DOCNO> 121392 </DOCNO>
Late superhumps and the stream-disc impact in IY UMa


  We use the hot spot eclipse times of the newly discovered deeply-eclipsing
dwarf nova IY UMa to trace out the shape of its disc during the late superhump
era. We find an eccentric disc. We show that the brightness of the stream-disc
impact region varies as expected with |deltaV|^2, where deltaV is the
differential velocity of the stream with respect to the velocity of the disc at
the impact point. We conclude that the hot spot is the source of late superhump
light.

</DOC>
<DOC>
<DOCNO> 10627 </DOCNO>
Microscopic Theory of Dipole-Exchange Spin Waves in Ferromagnetic Films:


  The linear and nonlinear processes in ferromagnetic films at low temperatures
T<< Tc are studied in a microscopic theory. Both the long-range magnetic
dipole-dipole and the Heisenberg exchange interactions to nearest and
next-nearest neighbors are included. The results obtained for the linearized
spin-wave spectrum are compared with previous macroscopic theories. For
ultrathin films (or for large wave vectors) the microscopic theory provides
important corrections. The nonlinear dynamics of the spin waves are studied
through a finite-temperature perturbation theory based on Feynman diagrams. We
obtain explicit results for the energy shift and damping (or reciprocal
lifetime) of the dipole-exchange spin waves due to all possible three-magnon
and four-magnon processes involving combinations of the surface and quantized
bulk spin waves at low temperatures. To investigate different dipole
interaction strengths (relative to the exchange) numerical results are
presented using parameters for Fe, EuO, and GdCl3.

</DOC>
<DOC>
<DOCNO> 68120 </DOCNO>
Flavour-Conserving CP Phases in Supersymmetry and Implications for


  We study rare exclusive B decays based on the quark-level transition
b->s(d)l^+l^-, where l=e or mu, in the context of supersymmetric theories with
minimal flavour violation. We present analytic expressions for various mixing
matrices in the presence of new CP-violating phases, and examine their impact
on observables involving B and \bar{B} decays. An estimate is obtained for
CP-violating asymmetries in B->K^(*)l^+l^- and B->rho(pi)l^+l^- decays for the
dilepton invariant mass region 1.2 GeV < M_{l^+l^-}< M_{J/psi}. As a typical
result, we find a CP-violating partial width asymmetry of about -6% (-5%) in
the case of B->pi (B->rho) in effective supersymmetry with phases of O(1),
taking into account the measurement of the inclusive b->s gamma branching
fraction. On the other hand, CP asymmetries of less than 1% are predicted in
the case of B->K^(*). We argue that it is not sufficient to have additional CP
phases of O(1) to observe large CP-violating effects in exclusive b->s(d)l^+l^-
decays.

</DOC>
<DOC>
<DOCNO> 152568 </DOCNO>
Hierarchy Stabilization in Warped Supersymmetry


  We show that exponentially large warp factor hierarchies can be dynamically
generated in supersymmetric compactifications. The compactification we consider
is the supersymmetric extension of the Randall-Sundrum model. The crucial issue
is the stabilization of the radius modulus for large warp factor. The
stabilization sector we employ is very simple, consisting of two pure
Yang--Mills sectors, one in the bulk and the other localized on a brane. The
only fine-tuning required in our model is the cancellation of the cosmological
constant, achieved by balancing the stabilization energy against supersymmetry
breaking effects. Exponentially large warp factors arise naturally, with no
very large or small input parameters. To perform the analysis, we derive the
4-dimensional effective theory for the supersymmetric Randall-Sundrum model,
with a careful treatment of the radius modulus. The manifestly (off-shell)
supersymmetric form of this effective lagrangian allows a straightforward and
systematic treatment of the non-perturbative dynamics of the stabilization
sector.

</DOC>
<DOC>
<DOCNO> 84524 </DOCNO>
Gauge symmetries in Ashtekar's formulation of general relativity


  It might seem that a choice of a time coordinate in Hamiltonian formulations
of general relativity breaks the full four-dimensional diffeomorphism
covariance of the theory. This is not the case. We construct explicitly the
complete set of gauge generators for Ashtekar's formulation of canonical
gravity. The requirement of projectability of the Legendre map from
configuration-velocity space to phase space renders the symmetry group a gauge
transformation group on configuration-velocity variables. Yet there is a sense
in which the full four-dimensional diffeomorphism group survives. Symmetry
generators serve as Hamiltonians on members of equivalence classes of solutions
of Einstein's equations and are thus intimately related to the so-called
"problem of time" in an eventual quantum theory of gravity.

</DOC>
<DOC>
<DOCNO> 13596 </DOCNO>
Sympathetic cooling of bosonic and fermionic Lithium gases towards


  Sympathetic cooling of two atomic isotopes is experimentally investigated.
Using forced evaporation of a bosonic 7Li gas in a magnetic trap, a sample of 3
10^5 6Li fermions has been sympathetically cooled to 9(3)muK, corresponding to
2.2(0.8) times the Fermi temperature. The measured rate constant for 2-body
inelastic collisions of 7Li |2,2> state at low magnetic field is
1.0^{+0.8}_{-0.5} 10^-14 cm^3s^-1.

</DOC>
<DOC>
<DOCNO> 67788 </DOCNO>
An improved time-dependent Hartree-Fock approach for scalar \phi^4 QFT


  The $\lambda \phi^4$ model in a finite volume is studied within a
non-gaussian Hartree-Fock approximation (tdHF) both at equilibrium and out of
equilibrium, with particular attention to the structure of the ground state and
of certain dynamical features in the broken symmetry phase. The mean-field
coupled time-dependent Schroedinger equations for the modes of the scalar field
are derived and the suitable procedure to renormalize them is outlined. A
further controlled gaussian approximation of our tdHF approach is used in order
to study the dynamical evolution of the system from non-equilibrium initial
conditions characterized by a uniform condensate. We find that, during the slow
rolling down, the long-wavelength quantum fluctuations do not grow to a
macroscopic size but do scale with the linear size of the system, in accordance
with similar results valid for the large $N$ approximation of the O(N) model.
This behavior undermines in a precise way the gaussian approximation within our
tdHF approach, which therefore appears as a viable mean to correct an unlikely
feature of the standard HF factorization scheme, such as the so-called
``stopping at the spinodal line'' of the quantum fluctuations. We also study
the dynamics of the system in infinite volume with particular attention to the
asymptotic evolution in the broken symmetry phase. We are able to show that the
fixed points of the evolution cover at most the classically metastable part of
the static effective potential.

</DOC>
<DOC>
<DOCNO> 70316 </DOCNO>
Isospin breaking exposed in f0(980)- a0(980) mixing


  We suggest that mixing between the f0(980) and a0(980), due to their
dynamical interaction with the nearby KKbar thresholds, can give rise to a
significantly enhanced production rate of a0(980) relative to a2(1320) in pp ->
ps (eta pi0) pf as xF -> 0. The peaking of the cross section as phi -> 0 should
also occur. We show that such effects are seen in data and deduce that the
f0(980) - a0(980) mixing intensity is 8 +/- 3 %.

</DOC>
<DOC>
<DOCNO> 102239 </DOCNO>
Hopf instantons, Chern-Simons vortices, and Heisenberg ferromagnets


  The dimensional reduction of the three-dimensional fermion-Chern-Simons model
(related to Hopf maps) of Adam et el. is shown to be equivalent to (i) either
the static, fixed--chirality sector of our non-relativistic spinor-Chern-Simons
model in 2+1 dimensions, (ii) or a particular Heisenberg ferromagnet in the
plane.

</DOC>
<DOC>
<DOCNO> 102113 </DOCNO>
Non-Local Equivariant Star Product on the Minimal Nilpotent Orbit


  We construct a unique G-equivariant graded star product on the algebra
$S(g)/I$ of polynomial functions on the minimal nilpotent coadjoint orbit
$\Omin$ of G where G is a complex simple Lie group and $g\neq\sl_2(C)$. This
strengthens the result of Arnal, Benamor, and Cahen.
  Our main result is to compute, for G classical, the star product of a
momentum function $\mu_x$ with any function f. We find $\mu_x\star
f=\mu_xf+\half\{\mu_x,f\}t+\Lambda^x(f)t^2$. For $\g$ different from
$sp_n(\C)$, $\Lambda^x$ is not a differential operator. Instead $\Lamda^x$ is
the left quotient of an explicit order 4 algebraic differential operator $D^x$
by an order 2 invertible diagonalizable operator. Precisely,
$\Lambda^x=-{1/4}\frac{1}{E'(E'+1)}D^x$ where $E'$ is a positive shift of the
Euler vector field. Thus $\mu_x\star f$ is not local in f.
  Using $\star$ we construct a positive definite hermitian inner product on
$Sg/I$. The Hilbert space completion of $Sg/I$ is then a unitary representation
of $G$. This quantizes $\Omin$ in the sense of geometric quantization and the
orbit method.

</DOC>
<DOC>
<DOCNO> 151059 </DOCNO>
Lagrange Brackets and U(1) fields


  The idea of a companion Lagrangian associated with $p$-Branes is extended to
include the presence of U(1) fields. The Brane Lagrangians are constructed with
$F_{ij}$ represented in terms of Lagrange Brackets, which make manifest the
reparametrisation invariance of the theory; these are replaced by Poisson
Brackets in the companion Lagrangian, which is now covariant under field
redefinition. The ensuing Lagrangians possess a similar formal structure to
those in the absence of an anti-symmetric field tensor.

</DOC>
<DOC>
<DOCNO> 120146 </DOCNO>
Some aspects of the chemical evolution of 4He in the Galaxy: the He/H


  Two aspects of the chemical evolution of 4He in the Galaxy are considered on
the basis of a sample of disk planetary nebulae by the application of
corrections due to the contamination of 4He from the progenitor stars. First,
the He/H radial gradient is analyzed, and then, the helium to heavy element
enrichment ratio is determined for metallicities up to the solar value.

</DOC>
<DOC>
<DOCNO> 119412 </DOCNO>
Carbon and Oxygen Galactic Abundance Gradients: A Comparative Study of


  Chemical evolution models for the Galactic disk under an inside-out formation
scenario are presented for seven sets of stellar yields, all of them metal
dependent. In particular, the effects of yields from massive and
low-and-intermediate-mass stars on the C/O chemical history of the solar
neighborhood and on abundance gradients are discussed comparing the predictions
with abundance ratios from nearby HII regions, B-stars, dwarf stars, and the
Sun.
  In the solar vicinity, the increase of C/O with metallicity is due to massive
stars alone. Models with yields by Maeder (1992) or by Portinari, Chiosi, &
Bressan (1998) reproduce the observed C/O increase with metallicity, while
models assuming yields by Woosley & Weaver (1995) and Woosley, Langer, & Weaver
(1993) do not. Models based on yields by Maeder (1992) are in agreement with
the C/O gradient, while those based on yields by Portinari et al. (1998) or by
Woosley & Weaver (1995) and Woosley et al. (1993) are not. To match both, the
C/O enrichment history of the solar neighborhood and the C/O local gradient,
models call for: i) yields that take into account metal-dependent stellar
winds; and ii) for massive stars, a mass-loss rate with a metallicity
dependence not as simple as Z^{0.5}.
  C/O abundance ratios predicted with yields by Marigo, Bressan, & Chiosi
(1996, 1998) are higher than those with yields by Renzini & Voli (1981), which
in turn are higher than those with yields by the van den Hoek & Groenewegen
(1997).

</DOC>
<DOC>
<DOCNO> 9627 </DOCNO>
Experimental and numerical signatures of dynamical crossover in


  By means of NMR experiment and MD computer simulation we investigate the
dynamical properties of a chloroadamantane orientationally disordered crystal.
We find a plastic-plastic dynamical transition at T_x ~ 330 K in the
pico-nanosecond regime. It is interpreted as the rotational analogue of the
Goldstein crossing temperature between quasi-free diffusion and activated
regime predicted in liquids. Below T_x, NMR experimental data are well
described by a Frenkel model corresponding to a strongly anisotropic motion. At
higher temperatures, a drastic deviation is observed toward quasi-isotropic
rotational diffusion. Close to T_x, we observe that two-step relaxations
emerge. An interpretation which is based on the present study of a specific
heat anomaly detected by a recent calorimetric experiment is proposed.

</DOC>
<DOC>
<DOCNO> 70656 </DOCNO>
Effective theories and hadronic bound states


  Recent progress in the description of the properties of hadronic atoms on the
basis of non-relativistic effective Lagrangian approach and Chiral Perturbation
Theory (ChPT) is reported. For the case of the pi(+)pi(-) atom decay, the
problem is completely solved, both conceptually and numerically. For the pi(-)p
atom, a general expression for the ground-state energy is obtained in the first
non-leading order in isospin breaking, and the numerical analysis is carried
out at O(p^2) in ChPT. We briefly consider a possible solution of the
"potential model puzzle" in the hadronic atom problem, providing a constructive
algorithm for the derivation of the isospin-breaking part of the short-range
hadronic potential from field theory.

</DOC>
<DOC>
<DOCNO> 121685 </DOCNO>
The EMSS Radio Loud Quasar Sample


  We construct the first X-ray selected sample of radio-loud quasars from the
EMSS survey. The X-ray selection allows us to explore the properties of
radio-loud quasars 10-100 weaker than classical samples in the radio band.
There are no radio-loud quasars whose synchrotron peak reaches the UV-soft
X-ray band at these (radio) flux levels (as occurs for BL Lac objects selected
in the X-ray band), but they appear to have comparatively stronger optical-UV
emission. We suggest that this can be ascribed to a significant contribution
from a quasi-thermal optical-UV component, emerging due to the comparatively
weak non-thermal emission. The detection of sources at low radio fluxes also
shows the presence of a large population of steep spectrum quasars, and the
lack of the predicted turnover in the quasar counts.

</DOC>
<DOC>
<DOCNO> 116549 </DOCNO>
Potential equations for plasmas round a rotating black hole


  The generalized Helmholtz equations of relativistic multifluid plasmas can be
integrated for axisymmetric equilibria in close analogy to the magnetic flux
conservation law in ideal magnetohydrodynamics (J. D. Bekenstein and E. Oron,
Phys. Rev. D 18, 1809 (1978)). The results are, for each fluid component, two
flux functions and a potential equation for the poloidal stream function.
Ampere's equation for the four-potential A_\nu is reduced to two coupled
equations for the time-like and the toroidal component. So we have altogether
four potential equations for a two-component plasma; they can be derived from a
variational principle.

</DOC>
<DOC>
<DOCNO> 119328 </DOCNO>
Large-Scale Power Spectrum and Structures From the ENEAR galaxy Peculiar


  We estimate the mass density fluctuations power spectrum (PS) on large scales
by applying a maximum likelihood technique to the peculiarvelocity data of the
recently completed redshift-distance survey of early-type galaxies (ENEAR). The
general results are in agreement with the high amplitude power spectra found
from similar analysis of other independent all-sky catalogs of peculiar
velocity data such as MARK III and SFI. For Lambda & Open CDM COBE normalized
PS models, the best-fit parameters are confined by a contour approximately
defined by Omega h^{1.3}=0.377+-0.08 and Omega h^{0.88}=0.517+-0.083,
respectively. Gamma-shape models, free of COBE normalization, resultsin the
weak constraint of $\Gamma \geq 0.17$ and in the rather stringent constraint of
sigma_8 Omega^{0.6}=1.0+-0.25. All quoted uncertainties refer to 3-sigma
confidence-level. The calculated PS is used as a prior for Wiener
reconstruction of the density field at different resolutions and the
three-dimensional velocity field within a volume of radius ~80 Mpc/h. All major
structures in the nearby universe are recovered and are well matched to those
predicted from all-sky redshift surveys.

</DOC>
<DOC>
<DOCNO> 120024 </DOCNO>
Sinks of Light Elements in Stars - Part III


  The fragile light elements lithium, beryllium, and boron are easily destroyed
in stellar interiors, and are thus superb probes of physical processes occuring
in the outer stellar layers. The light elements are also excellent tracers of
the chemical evolution of the Galaxy, and can test big bang nucleosynthesis
(BBN). These inter-related topics are reviewed with an emphasis on stellar
physics.
  In Part I (presented by CPD), an overview is given of the physical processes
which can modify the surface abundances of the light elements, with emphasis on
Population I dwarfs - convection; gravitational settling, thermal diffusion,
and radiative levitation; slow mixing induced by gravity waves or rotation. We
will discuss the increasingly large body of data which begin to enable us to
discern the relative importance of these mechanisms in Population I main
sequence stars.
  In Part II (presented by MHP), discussion is extended to the issue of whether
or not the halo Li plateau is depleted, and includes the following topics: Li
dispersion in field and globular cluster stars, Li production vs. destruction
in Li-rich halo stars, and constraints from 6Li. Also discussed are trends with
metal abundance and Teff and implications for chemical evolution and BBN.
  In Part III (presented by CC), evidence is reviewed that suggests that in
situ mixing occurs in evolved low mass Population I and Population II stars.
Theoretical mechanisms that can create such mixing are discussed, as well as
their implications in stellar yields.

</DOC>
<DOC>
<DOCNO> 72311 </DOCNO>
A Matrix Approach to Numerical Solution of the DGLAP Evolution Equations


  A matrix-based approach to numerical integration of the DGLAP evolution
equations is presented. The method arises naturally on discretisation of the
Bjorken x variable, a necessary procedure for numerical integration. Owing to
peculiar properties of the matrices involved, the resulting equations take on a
particularly simple form and may be solved in closed analytical form in the
variable t=ln(alpha_0/alpha). Such an approach affords parametrisation via data
x bins, rather than fixed functional forms. Thus, with the aid of the full
correlation matrix, appraisal of the behaviour in different x regions is
rendered more transparent and free of pollution from unphysical
cross-correlations inherent to functional parametrisations. Computationally,
the entire programme results in greater speed and stability; the matrix
representation developed is extremely compact. Moreover, since the parameter
dependence is linear, fitting is very stable and may be performed analytically
in a single pass over the data values.

</DOC>
<DOC>
<DOCNO> 151987 </DOCNO>
Type IIB Orientifolds without Untwisted Tadpoles, and non-BPS D-branes


  We discuss the construction of six- and four-dimensional Type IIB
orientifolds with vanishing untwisted RR tadpoles, but generically non-zero
twisted RR tadpoles. Tadpole cancellation requires the introduction of D-brane
systems with zero untwisted RR charge, but non-zero twisted RR charges. We
construct explicit models containing branes and antibranes at fixed points of
the internal space, or non-BPS branes partially wrapped on it. The models are
non-supersymmetric, but are absolutely stable against decay to supersymmetric
vacua. For particular values of the compactification radii tachyonic modes may
develop, triggering phase transitions between the different types of non-BPS
configurations of branes, which we study in detail in a particular example. As
an interesting spin-off, we show that the $\IT^6/\IZ_4$ orientifold without
vector structure, previously considered inconsistent due to uncancellable
twisted tadpoles, can actually be made consistent by introducing a set of
brane-antibrane pairs whose twisted charge cancels the problematic tadpole.

</DOC>
<DOC>
<DOCNO> 119936 </DOCNO>
HCN in the inner envelope of {chi} Cygni


  We have detected the (0,11c,0)J=3-2 and (0,0,0)J=8-7 transitions of HCN
towards the S star {chi} Cygni. The excitation requirements of these
transitions are too high to be satisfied in the outer envelope of the star, and
the emission must originate within {solar}20 stellar radii, ie. the molecule
must be forming close to the star. This conclusion is supported by a model for
AGB stars in which molecules including HCN form in a shocked wind close to the
stellar surface.

</DOC>
<DOC>
<DOCNO> 10997 </DOCNO>
Vortex ordering in fully-frustrated superconducting systems with dice


  The structure and the degenracy of the ground state of a fully-frustrated
XY-model are investigated for the case of a dice lattice geometry.
 The results are applicable for the description of Josephson junction arrays
and thin superconducting wire networks in the external magnetic field providing
half-integer number of flux quanta per plaquette. The mechanisms of disordering
of vortex pattern in such systems are briefly discussed.

</DOC>
<DOC>
<DOCNO> 10878 </DOCNO>
Non-hermitean delocalization in an array of wells with variable-range


  Nonhermitean hamiltonians of convection-diffusion type occur in the
description of vortex motion in the presence of a tilted magnetic field as well
as in models of driven population dynamics. We study such hamiltonians in the
case of rectangular barriers of variable size. We determine Lyapunov exponent
and wavenumber of the eigenfunctions within an adiabatic approach, allowing to
reduce the original d=2 phase space to a d=1 attractor. PACS
numbers:05.70.Ln,72.15Rn,74.60.Ge

</DOC>
<DOC>
<DOCNO> 10265 </DOCNO>
Orientational Ordering and Binding in Alkali doped C60 solids


  The binding energy of A3C60, a conductor, is described well by an ionic solid
type calculation. This succeeds because there is little overlap between
molecular wave functions on neighbouring sites, so that electrons are
practically localized on-shell. This leads one to believe that even in A4C60
and A6C60 systems such calculation may suffice. However, for large charge on
the anion, there is a possibility for some electrons to delocalize and go into
the s-band. We calculate binding energy, keeping these delocalised electrons x,
as a parameter and minimize the energy w.r.t. it. We take the intermolecular
interaction to be arising out of a C-C potential of 6-exp form and a screened
Coulomb interaction between the anions and cations and among themselves. Model
calculations are presented for K1C60, K3C60, K4C60 and K6C60 for which the
minimum energy state shows no delocalisation. Cohesive Energy dependence on
Lattice constant is used to calculate Bulk Modulus for all systems. We have got
a reasonably good resemblance with experimental values. Further, we observe
that the cohesive energy shows poor resemblance with experimental values.
Further, delocalisation of a fraction of electron at the centre of double bond
show considerable increase in cohesive energy.

</DOC>
<DOC>
<DOCNO> 121823 </DOCNO>
Keck Hires Observations of the QSO First J104459.6+365605: Evidence for


  This paper presents an analysis of a Keck HIRES spectrum of the QSO FIRST
J104459.6+365605. The line of sight towards the QSO contains two clusters of
outflowing clouds that give rise to broad blue shifted absorption lines. The
outflow velocities of the clouds range from -200 to -1200 km/s and from -3400
to -5200 km/s, respectively. The width of the individual absorption lines
ranges from 50 to more than 1000 km/s. The most prominent absorption lines are
those of Mg II, Mg I, and Fe II. The low ionization absorption lines occur at
the same velocities as the most saturated Mg II lines, showing that the Fe II,
Mg I and Mg II line forming regions must be closely associated. Many absorption
lines from excited states of Fe II are present, allowing a determination of the
population of several low lying energy levels. From this we determine an
electron density in the Fe II line forming regions of 4000 per cubic cm.
Modelling the ionization state of the absorbing gas with this value of the
electron density as a constraint, we find that the distance between the Fe II
and Mg I line forming region and the continuum source is of order 700 parsec.
  From the correspondence in velocity between the Fe II, Mg I and Mg II lines
we infer that the Mg II lines must be formed at the same distance. The Mg II
absorption fulfills the criteria for Broad Absorption Lines defined by Weymann
et al. (1991). This large distance is surprising, since BALs are generally
thought to be formed in outflows at a much smaller distance from the nucleus.

</DOC>
<DOC>
<DOCNO> 9911 </DOCNO>
Scaling Behaviour of Developing and Decaying Networks


  We find that a wide class of developing and decaying networks has scaling
properties similar to those that were recently observed by Barab\'{a}si and
Albert in the particular case of growing networks. The networks considered here
evolve according to the following rules: (i) Each instant a new site is added,
the probability of its connection to old sites is proportional to their
connectivities. (ii) In addition, (a) new links between some old sites appear
with probability proportional to the product of their connectivities or (b)
some links between old sites are removed with equal probability.

</DOC>
<DOC>
<DOCNO> 99621 </DOCNO>
On the Counting of Colored Tangles


  The connection between matrix integrals and links is used to define matrix
models which count alternating tangles in which each closed loop is weighted
with a factor n, i.e. may be regarded as decorated with n possible colors. For
n=2, the corresponding matrix integral is that recently solved in the study of
the random lattice six-vertex model. The generating function of alternating
2-color tangles is provided in terms of elliptic functions, expanded to 16-th
order (16 crossings) and its asymptotic behavior is given.

</DOC>
<DOC>
<DOCNO> 102082 </DOCNO>
On weight graphs for nilpotent Lie algebras I


  We introduce the concept of weight graph for the weight system $P\frak{g}(T)$
of a finite dimensional nilpotent Lie algebra $\frak{g}$ and analyze the
necessary conditions for a $(p,q)$-graph to be a weight graph for some
$\frak{g}$.

</DOC>
<DOC>
<DOCNO> 122570 </DOCNO>
Models for the Origin of the Knee in the Cosmic-Ray Spectrum


  A sudden steepening of the cosmic-ray energy spectrum (the knee) is observed
at an energy of about 3 PeV (1 PeV = $10^{15}$ eV). The experimental study of
the PeV cosmic rays has intensified greatly during the last 3 years. The recent
results on extensive air showers allow us to conclude that: a) the knee has an
astrophysical origin; b) the `sharpness' and the fine structure of the knee
rule out `Galactic Modulation' as the origin of the knee; c) most likely the
knee is the result of the explosion of a single, recent, nearby supernova.

</DOC>
<DOC>
<DOCNO> 85205 </DOCNO>
Conflict between the Gravitational Field Energy and the Experiments


  From the equivalence principle and true gravitational (G) time dilation
experiments it is concluded that ``matter is not invariable after a change of
relative position with respect to other bodies''. As a general principle (GP),
such variations cannot be locally detected because the basic parameters of all
of the 'well-defined parts' of the instruments change, lineally, in the same
proportion with respect to their original values''. Only observers that don't
change of position can detect them. Thus, to relate quantities measured by
observers in different G potentials they must be previously transformed after
Lorenz and G transformations derived from experiments. They are account for all
of the ``G tests''. However ``they are not consistent with the presumed energy
exchange between the field and the bodies''. The lack of energy of the G field
is justified from the GP, according to which particles models made up of
photons in stationary state obey same inertial and G laws as particle. Such
model has been previously tested with relativistic quantum-mechanics and all of
the G tests.
  PACS: 04.80.cc, 04.20.Cv, 04.80.-y, 98.80.Cq

</DOC>
<DOC>
<DOCNO> 80636 </DOCNO>
High Temperature 3D QCD: Dimensional Reduction at Work


  We investigate the three-dimensional SU(3) gauge theory at finite temperature
in the framework of dimensional reduction. The large scale properties of this
theory are expected to be conceptually more complicated than in four
dimensions. The dimensionally reduced action is computed in closed analytical
form. The resulting effective two-dimensional theory is studied numerically
both in the electric and magnetic sector. We find that dimensional reduction
works excellently down to temperatures of 1.5 times the deconfinement phase
transition temperature and even on rather short length scales. We obtain strong
evidence that for ${\rm QCD}_3$, even at high temperature the colour averaged
potential is represented by the exchange of a single state, at variance with
the usual Debye screening picture involving a pair of electric gluons.

</DOC>
<DOC>
<DOCNO> 152080 </DOCNO>
Dp-D(p+4) in Noncommutative Yang-Mills


  An anti-self-dual instanton solution in Yang-Mills theory on noncommutative
${\R}^4$ with an anti-self-dual noncommutative parameter is constructed. The
solution is constructed by the ADHM construction and it can be treated in the
framework of the IIB matrix model. In the IIB matrix model, this solution is
interpreted as a system of a Dp-brane and D(p+4)-branes, with the Dp-brane
dissolved in the worldvolume of the D(p+4)-branes. The solution has a parameter
that characterises the size of the instanton. The zero of this parameter
corresponds to the singularity of the moduli space. At this point, the solution
is continuously connected to another solution which can be interpreted as a
system of a Dp-brane and D(p+4)-branes, with the Dp-brane separated from the
D(p+4)-branes. It is shown that even when the parameter of the solution comes
to the singularity of the moduli space, the gauge field itself is non-singular.
A class of multi-instanton solutions is also constructed.

</DOC>
<DOC>
<DOCNO> 121195 </DOCNO>
Luminous hot accretion disks


  We find a new two-temperature hot branch of equilibrium solutions for
stationary accretion disks around black holes. In units of Eddington accretion
rate defined as $10L_{\rm Edd}/c^2$, the accretion rates to which these
solutions correspond are within the range $\dot{m}_1 \la \dot{m} \la 1$, here
$\dot{m}_1$ is the critical rate of advecti$. In these solutions, the energy
loss rate of the ions by Coulomb energy transfer between the ions and electrons
is larger than the viscously heating rate and it is the advective heating
together with the viscous dissipation that balances the Coulomb cooling of
ions. When $\dot{m}_1 \la \dot{m} \la \dot{m}_2$, where $\dot{m}_2 \sim 5
\dot{m}_1 < 1$, the accretion flow remains hot throughout the disk. When
$\dot{m}_2 \la \dot{m}\la 1$, Coulomb interaction will cool the inner region of
the disk within a certain radius ($r_{\rm tr} \sim$ several -- tens of
Schwarzschild radii or larger depending on the accretion rate and the outer
boundary condition) and the disk will collapse onto the equatorial plane and
form an optically thick cold annulus. Compared to ADAF, these hot solutions are
much more luminous because of the high accretion rate and efficiency,
therefore, we name them luminous hot accretion disks.

</DOC>
<DOC>
<DOCNO> 151386 </DOCNO>
Excitations in Hot Non-Commutative Theories


  We study the dispersion relation for scalar excitations in supersymmetric,
non-commutative theories at finite temperature. In N=4 Yang-Mills the low
momenta modes have superluminous group velocity. In the massless Wess-Zumino
model the minimum of the dispersion relation is at non zero momentum for
temperatures above T_0 ~ (g \theta)^(-1\2). We briefly comment on N=2
Yang-Mills at finite density.

</DOC>
<DOC>
<DOCNO> 84516 </DOCNO>
The quantization of gravity - an introduction


  This is an introduction to quantum gravity, aimed at a fairly general
audience and concentrating on what have historically two main approaches to
quantum gravity: the covariant and canonical programs (string theory is not
covered). The quantization of gravity is discussed by analogy with the
quantization of the electromagnetic field. The conceptual and technical
problems of both approaches are discussed, and the paper concludes with a
discussion of evidence for quantum gravity from the rest of physics.
  The paper assumes some familiarity with non-relativistic quantum mechanics,
special relativity, and the Lagrangian and Hamiltonian formulations of
classical mechanics; some experience with classical field theory, quantum
electrodynamics and the gauge principle in electromagnetism might be helpful
but is not required. No knowledge of general relativity or of quantum field
theory in general is assumed.

</DOC>
<DOC>
<DOCNO> 71099 </DOCNO>
Comment on "No Primordial Magnetic Field from Domain Walls"


  We comment on the recent preprint hep-ph/0007123 by M.B. Voloshin, claiming
that domain walls are diamagnetic. We show that the results presented therein
are based on an incorrect treatment of the zero mode contribution to the vacuum
energy density. We also shown that the correct treatment leads to the
conclusion that domain walls are ferromagnetic, and can generate a primordial
magnetic field.

</DOC>
<DOC>
<DOCNO> 116841 </DOCNO>
The effects of the rotation in plasma


  Electric and magnetic self-fields can exist in the rotating plasma. A
self-sustained rotation can be established in the plasma. The disturbed
distribution function of rotating plasma is derived from the Vlasov equation.
The propagation of waves in rotating plasma differs from that in the usual
plasma. New terms for Landau damping appear. The local rotational behaviour may
become prevailing.

</DOC>
<DOC>
<DOCNO> 10439 </DOCNO>
Periodic forcing in viscous fingering of a nematic liquid crystal


  We study viscous fingering of an air -- nematic interface in a radial
Hele-Shaw cell when periodically switching on and off an electric field, which
reorients the nematic and thus changes the viscosity, the surface tension, and
its anisotropy (mainly enforced by a single groove in the cell). We observe
lateral undulations in the fingers which correlate with the switching
frequency, as well as with tip oscillations which give maximal velocity to
smallest curvatures. These oscillations appear to be decoupled from spontaneous
(noise-induced) side branching. We conclude that the lateral undulations are
generated by successive relaxations between two limiting patterns. The change
between these two selected patterns is mainly due to the change in the
anisotropy. This scenario is confirmed by numerical simulations in the strip
geometry, using a phase-field model for anisotropic viscous fingering.

</DOC>
<DOC>
<DOCNO> 71273 </DOCNO>
Mapping out the QCD phase transition in multiparticle production


  We analyze multiparticle production in a thermal framework for 7 central
nucleus nucleus collisions, $e^+$+ $e^-$ annihilation into hadrons on the Z
resonance and 4 hadronic reactions (p+p and p+$\bar{p}$ with partial centrality
selec tion), with center of mass energies ranging from $\sqrt{s}$= 2.6 GeV (per
nucleon pair) to 1.8 TeV. Thermodynamic parameters at chemical freeze-out
(temperature and baryon and strangeness fugacities) are obtained from
appropriate fits, generally improving in quality for reactions subjected to
centrality cuts. All systems with nonvanishing fugacities are extrapolated
along trajectories of equal energy density, density and entropy density to zero
fugacities. The so obtained temperatures extrapolated to zero fugacities as a
function of initial energy density $\epsilon_{in}$ universally show a strong
rise followed by a saturating limit of $T_{lim}$ = 155 $\pm$ 6 $\pm$ 20 MeV. We
interpret this behaviour as mapping out the boundary between quark gluon plasma
and hadronic phases. The ratio of strange antiquarks to light ones as a
function of the initial energy density $\epsilon_{in}$ shows the same behaviour
as the temperature, saturating at a value of 0.365 $\pm$ 0.033 $\pm$ 0.07. No
distinctive feature of 'strangeness enhancement' is seen for heavy ion
collisions relative to hadronic and leptonic reactions, when compared at the
same initial energy density.

</DOC>
<DOC>
<DOCNO> 8464 </DOCNO>
Thermodynamic properties of the periodic nonuniform spin-1/2 isotropic


  Using the Jordan-Wigner transformation and the continued-fraction method we
calculate exactly the density of states and thermodynamic quantities of the
periodic nonuniform spin-1/2 isotropic XY chain in a transverse field. We
discuss in detail the changes in the behaviour of the thermodynamic quantities
caused by regular nonuniformity. The exact consideration of thermodynamics is
extended including a random Lorentzian transverse field. The presented results
are used to study the Peierls instability in a quantum spin chain. In
particular, we examine the influence of a non-random/random field on the
spin-Peierls instability with respect to dimerization.

</DOC>
<DOC>
<DOCNO> 150844 </DOCNO>
Compactification and Identification of Branes in the Kaluza-Klein


  We study the properties of branes in supergravity theory. We investigate a
class of systems consisting of an M5-brane in the Kaluza-Klein monopole
background with 1/4 supersymmetry in 11-dimensions. In the near core region of
the KK-monopoles, the exact supergravity solution corresponding to each of
these configurations is obtained. Then we argue the compactified 10-dimensional
systems and suggest a way of unambiguous identification of branes in this
background. Here the location of Dirac string type singularity accompanied by
the D6-branes plays an important role. The method is essentially the same as
that of (p,q)5-branes or (p,q)-strings within the 7-brane background in the IIB
theory. We also argue the phenomena of D4-brane creation from D6-branes.

</DOC>
<DOC>
<DOCNO> 100130 </DOCNO>
Eigenfunctions of $GL(N,\RR)$ Toda chain: The Mellin-Barnes


  The recurrent relations between the eigenfunctions for $GL(N,\RR)$ and
$GL(N-1,\RR)$ quantum Toda chains is derived. As a corollary, the Mellin-Barnes
integral representation for the eigenfunctions of a quantum open Toda chain is
constructed for the $N$-particle case.

</DOC>
<DOC>
<DOCNO> 151498 </DOCNO>
Non-Supersymmetric SO(3)-Invariant Deformations of N=1* Vacua and their


  We study the SO(3)-invariant relevant deformations of N=4 SU(N) gauge theory
using the methods of Polchinski and Strassler. We present the region of
parameter space where the non-supersymmetric vacuum is still described by
stable ``dielectric'' five branes within the supergravity approximation.

</DOC>
<DOC>
<DOCNO> 150673 </DOCNO>
A Quantum field theory of dyons


  We construct a classical field theory action which upon quantization via the
functional integral approach, gives rise to a consistent Dirac-string
independent quantum field theory. The approach entails a systematic derivation
of the correlators of all gauge invariant observables, and also of charged
dyonic fields. Manifest SO(2)-duality invariance and Lorentz invariance are
ensured by the PST-approach.

</DOC>
<DOC>
<DOCNO> 122970 </DOCNO>
The Hamburg/SAO Survey for Emission--Line Galaxies. IV. The Fourth List


  We present the fourth list with results of the Hamburg/SAO Survey for
Emission-Line Galaxies (HSS hereafter, SAO - Special Astrophysical Observatory,
Russia). The list is a result of the follow-up spectroscopy conducted with the
6m SAO RAS telescope in 1998, 1999 and 2000. The data of this snap-shot
spectroscopy survey confirmed 127 emission-line objects out of 176 observed
candidates and allowed their quantitative spectral classification. We could
classify 76 emission-line objects as BCG/HII galaxies or probable BCGs, 8 - as
QSOs, 2 - as Seyfert galaxies, 2 - as super-associations in a subluminous
spiral and an irregular galaxy, and 37 as low-excitation objects - either
starburst nuclei (SBN), or dwarf amorphous nuclei starburst galaxies (DANS). We
could not classify 2 ELGs. Furthermore, for 5 galaxies we did not detect any
significant emission lines. For 91 emission-line galaxies, the redshifts and/or
line intensities are determined for the first time. Of the remaining 28
previously known ELGs we give either improved data on the line intensities or
some independent measurements. The candidates were taken from three different
samples selected by different criteria. Among our first priority candidates we
achieved a detection rate of emission-line objects (ELGs + QSOs) of 68%, among
which 51% are BCGs. Observations of a random selected sample among our second
priority candidates showed that only ~10% are BCGs. We found that the confirmed
BCGs have usually a blue colour ((B-R) < 1.0) and a non-stellar appearance in
the APM database. Our third sample is comprised of second priority candidates
fulfilling these criteria derived from the APM. Follow-up spectroscopy of a
small subsample indicates that the expected detection rate for BCGs is ~40%.

</DOC>
<DOC>
<DOCNO> 119529 </DOCNO>
Discovery of a narrow line Seyfert 1 galaxy


  We have discovered a Narrow-Line Seyfert 1 (NLS1) galaxy and identified it
with an ultrasoft X-ray source RX 215319-1514 detected with ROSAT. We present
its X-ray and optical spectral characteristics. Its redshift is found to be
0.0778+-0.0002. Its optical spectrum shows fairly strong Fe II emission lines,
and its X-ray spectrum has an extremely steep power-law index of Gamma
greater/equal 4, making it an extremely interesting example of this class of
AGNs. No low-energy absorption or variability is observed. The soft X-ray
(0.1-2.0 keV) luminosity is estimated to be 3.4-12.5 times 1e43 erg/s,
depending on the spectral model.

</DOC>
<DOC>
<DOCNO> 84105 </DOCNO>
On Gravity, Holography and the Quantum


  The holographic principle states that the number of degrees of freedom
describing the physics inside a volume (including gravity) is bounded by the
area of the boundary (also called the screen) which encloses this volume. A
stronger statement is that these (quantum) degrees of freedom live on the
boundary and describe the physics inside the volume completely. The obvious
question is, what mechanism is behind the holographic principle. Recently, 't
Hooft argued that the quantum degrees of freedom on the boundary are not
fundamental. We argue that this interpretation opens up the possibility that
the mapping between the theory in the bulk (the holographic theory) and the
theory on the screen (the dual theory) is always given by a (generalized)
procedure of stochastic quantization. We show that gravity causes differences
to the situation in Minkowski/Euclidean spacetime and argue that the fictitious
coordinate needed in the stochastic quantization procedure can be spatial. The
diffusion coefficient of the stochastic process is in general a function of
this coordinate. While a mapping of a bulk theory onto a (quantum) boundary
theory can be possible, such a mapping does not make sense in spacetimes in
which the area of the screen is growing with time. This is connected to the
average process in the formalism of stochastic quantization. We show where the
stochastic quantization procedure breaks down and argue, in agreement with `t
Hooft, that the quantum degrees of freedom are not fundamental degrees of
freedom. They appear as a limit of a more complex process.

</DOC>
<DOC>
<DOCNO> 40670 </DOCNO>
Jet algorithms. Wrapping up the subject


  This postscriptum to the theory of jet definition [hep-ph/9901444] summarizes
the points which did not find their way into the main text.

</DOC>
<DOC>
<DOCNO> 84694 </DOCNO>
Transport along Null Curves


  Fermi Transport is useful for describing the behaviour of spins or gyroscopes
following non-geodesic, timelike world lines. However, Fermi Transport breaks
down for null world lines. We introduce a transport law for polarisation
vectors along non-geodesic null curves. We show how this law emerges naturally
from the geometry of null directions by comparing polarisation vectors
associated with two distinct null directions. We then give a spinorial
treatment of this topic and make contact with the geometric phase of quantum
mechanics. There are two significant differences between the null and timelike
cases. In the null case (i) The transport law does not approach a unique smooth
limit as the null curve approaches a null geodesic. (ii) The transport law for
vectors is integrable, i.e the result depends only on the local properties of
the curve and not on the entire path taken. However, the transport of spinors
is not integrable: there is a global sign of topological origin.

</DOC>
<DOC>
<DOCNO> 68217 </DOCNO>
Phenomenology of the Flavor-Asymmetry in the Light-Quark Sea of the


  A phenomenological ansatz for the flavor-asymmetry of the light sea
distributions of the nucleon, based on the Pauli exclusion principle, is
proposed. This ansatz is compatible with the measured flavor-asymmetry of the
unpolarized sea distributions, $\bar{d}>\bar{u}$, of the nucleon. A prediction
for the corresponding polarized flavor-asymmetry is presented and shown to
agree with predictions of (chiral quark--soliton) models which successfully
reproduced the flavor-asymmetry of the unpolarized sea.

</DOC>
<DOC>
<DOCNO> 12379 </DOCNO>
Hermitian, symmetric and symplectic random ensembles: PDEs for the


  Given the Hermitian, symmetric and symplectic ensembles, it is shown that the
probability that the spectrum belongs to one or several intervals satisfies a
nonlinear PDE. This is done for the three classical ensembles: Gaussian,
Laguerre and Jacobi. For the Hermitian ensemble, the PDE (in the boundary
points of the intervals) is related to the Toda lattice and the KP equation,
whereas for the symmetric and symplectic ensembles the PDE is an inductive
equation, related to the so-called Pfaff-KP equation and the Pfaff lattice. The
method consists of inserting time-variables in the integral and showing that
this integral satisfies integrable lattice equations and Virasoro constraints.

</DOC>
<DOC>
<DOCNO> 12766 </DOCNO>
Magnets with strong geometric frustration


  A non-technical introduction to the theory of magnets with strong geometric
frustration is given, concentrating on magnets on corner-sharing (kagome,
pyrochlore, SCGO and GGG) lattices. Their rich behaviour is traced back to a
large ground-state degeneracy in model systems, which renders them highly
unstable towards perturbations. A systematic classification according to
properties of their ground states is discussed. Other topics addressed in this
overview article include a general theoretical framework for thermal order by
disorder; the dynamics of how the vast regions of phase space accessible at low
temperature are explored; the origin of the featureless magnetic susceptibility
fingerprint of geometric frustration; the role of perturbations; and spin ice.
The rich field of quantum frustrated magnets is also touched on.

</DOC>
<DOC>
<DOCNO> 102420 </DOCNO>
On the String-Theoretic Euler Number of 3-dimensional A-D-E


  The string-theoretic E-functions E_{str}(X;u,v) of normal complex varieties X
having at most log-terminal singularities are defined by means of
snc-resolutions. We give a direct computation of them in the case in which X is
the underlying space of the 3-dimensional A-D-E singularities by making use of
a canonical resolution process. Moreover, we compute the string-theoretic Euler
number for several compact complex threefolds with prescribed A-D-E
singularities.

</DOC>
<DOC>
<DOCNO> 40048 </DOCNO>
Photoproduction of phi(1020) mesons on the proton at large momentum


  The cross section for $\phi$ meson photoproduction on the proton has been
measured for the first time up to a four-momentum transfer -t = 4 GeV^2, using
the CLAS detector at the Thomas Jefferson National Accelerator Facility. At low
four-momentum transfer, the differential cross section is well described by
Pomeron exchange. At large four-momentum transfer, above -t = 1.8 GeV^2, the
data support a model where the Pomeron is resolved into its simplest component,
two gluons, which may couple to any quark in the proton and in the $\phi$.

</DOC>
<DOC>
<DOCNO> 70976 </DOCNO>
Lessons from Hadron Phenomenology


  Meson spectra can be well approximated by a specific form of a nonlinear
Regge trajectory which is consistent with a finite number of bound states. This
may have important consequencies for experiment, and may be a hint for the
theory.

</DOC>
<DOC>
<DOCNO> 10894 </DOCNO>
Explosion of a collapsing Bose-Einstein condensate


  We show that elastic collisions between atoms in a Bose-Einstein condensate
with attractive interactions lead to an explosion that ejects a large fraction
of the collapsing condensate. We study variationally the dynamics of this
explosion and find excellent agreement with recent experiments on magnetically
trapped Rubidium-85. We also determine the energy and angular distribution of
the ejected atoms during the collapse.

</DOC>
<DOC>
<DOCNO> 9906 </DOCNO>
Level Set Modeling of Transient Electromigration Grooving


  A numerical investigation of grain-boundary (GB) grooving by means of the
Level Set (LS) method is carried out. GB grooving is emerging as a key element
of electromigration drift in polycrystalline microelectronic interconnects, as
evidenced by a number of recent studies. The purpose of the present study is to
provide an efficient numerical simulation, allowing a parametric study of the
effect of key physical parameters (GB and surface diffusivities, grain size,
current density, etc) on the electromigration drift velocity as well as on the
morphology of the affected regions. An idealized polycrystalline interconnect
which consists of grains separated by parallel GBs aligned normal to the
average orientation of interconnect's surface is considered. Surface and
grain-boundary diffusion are the only diffusion mechanisms assumed. The
diffusion is driven by surface curvature gradients and by an externally applied
electric field. The corresponding mathematical system is an initial boundary
value problem for a two-dimensional Hamilton-Jacobi type equation. To solve for
the electrostatic problem at a given time step, a full model based on the
solution of Laplace's equation for the electric potential is employed. The
resulting set of linear algebraic equations (from the finite difference
discretization of the equation) is solved with an effective multigrid iterative
procedure. The details of transient slit and ridge formation processes are
presented and compared with theoretical predictions on steady-state grooving.

</DOC>
<DOC>
<DOCNO> 169743 </DOCNO>
On the possibility of quantum computation based on photon exchange


  We examine several proposed schemes by Franson et al. for quantum logic gates
based on non-local exchange interactions between two photons in a medium. In
these schemes the presence of a {\em single} photon in a given mode is supposed
to induce a large phase shift on another photon propagating in the same medium.
We conclude that the schemes proposed so far are not able to produce the
required conditional phase shift, even though the proposals contain many
stimulating and intriguing ideas.

</DOC>
<DOC>
<DOCNO> 101945 </DOCNO>
Hamiltonian dynamics on the moduli space of half weighted Bohr -


  Connecting ideas of geometric formulation of quantum mechanics with new
results in symplectic geometry a new approach to geometrical quantization
procedure is proposed. As a first result we verify that the correspondence
between "classical" Poisson bracket and "quantum" one takes place.

</DOC>
<DOC>
<DOCNO> 151299 </DOCNO>
Phase transition in scalar $\phi^4$-theory beyond the super daisy


  The temperature phase transition in scalar $\phi^4(x)$ field theory with
spontaneous symmetry breaking is investigated in a partly resummed perturbative
approach. The second Legendre transform is used and the resulting gap equation
is considered in the extrema of the free energy functional. It is found that
the phase transition is of first order in the super daisy as well as in a
certain beyond super daisy resummations. No unwanted imaginary parts in the
free energy are found but a loss of the smallness of the effective expansion
parameter near the phase transition temperature is found in both cases. This
means an insufficiency of the resummations or a deficit of the perturbative
approach.

</DOC>
<DOC>
<DOCNO> 123077 </DOCNO>
Adiabatic Losses and Stochastic Particle Acceleration in Gamma-Ray Burst


  We treat the problem of adiabatic losses and stochastic particle acceleration
in gamma-ray burst (GRB) blast waves that decelerate by sweeping up matter from
an external medium. The shocked fluid is assumed to be represented by a
homogeneous expanding shell. The energy lost by nonthermal particles through
adiabatic expansion is converted to the bulk kinetic energy of the outflow,
permitting the evolution of the bulk Lorentz factor Gamma of the blast wave to
be self-consistently calculated. The behavior of the system is shown to
reproduce the hydrodynamic self-similar solutions in the relativistic and
nonrelativistic limits, and the formalism is applicable to scenarios that are
intermediate between the adiabatic and fully radiative regimes. Nonthermal
particle energization through stochastic gyroresonant acceleration with
magnetic turbulence in the blast wave is treated by employing energy-gain rates
and diffusive escape timescales based upon expressions derived in the
quasilinear regime. If the magnetic field in the shocked fluid approaches its
equipartition value, this process can accelerate escaping particles to
>~10^{20} eV energies, consistent with the hypothesis that ultra-high energy
cosmic rays (UHECRs) are accelerated by GRB blast waves. Due to particle
trapping by the magnetic turbulence, only the highest energy particles can
escape during the prompt and afterglow phases of a GRB for acceleration by a
Kolmogorov spectrum of MHD turbulence. Lower energy particles begin to escape
as the blast wave becomes nonrelativistic and shock Fermi acceleration becomes
more important.

</DOC>
<DOC>
<DOCNO> 100497 </DOCNO>
Coarse Obstructions to Positive Scalar Curvature Metrics in Noncompact


  Block and Weinberger show that an arithmetic manifold can be endowed with a
positive scalar curvature metric if and only if its $\rationals$-rank exceeds
2. We show in this article that these metrics are never in the same coarse
class as the natural metric inherited from the base Lie group. Furthering the
coarse $C^\ast$-algebraic methods of Roe, we find a nonzero Dirac obstruction
in the $K$-theory of a particular operator algebra which encodes information
about the quasi-isometry type of the manifold as well as its local geometry.

</DOC>
<DOC>
<DOCNO> 151066 </DOCNO>
Zero modes in finite range magnetic fields


  We find a class of Fermion zero modes of Abelian Dirac operators in three
dimensional Euclidean space where the gauge potentials and the related magnetic
fields are nonzero only in a finite space region.

</DOC>
<DOC>
<DOCNO> 101399 </DOCNO>
Hyperbolic complex numbers in two dimensions


  A system of commutative hyperbolic complex numbers in 2 dimensions is studied
in this paper. Exponential and trigonometric forms are obtained for these
hyperbolic twocomplex numbers. Expressions are given for the elementary
functions of hyperbolic twocomplex variable. The functions of a hyperbolic
twocomplex variable which are defined by power series are analytic. Relations
of equality exist between partial derivatives of the real components a function
of a hyperbolic twocomplex variable. The integral of a twocomplex function
between two points is independent of the path connecting the points. A
hyperbolic twocomplex polynomial can be written as a product of linear or
quadratic factors, although the factorization may not be unique.

</DOC>
<DOC>
<DOCNO> 80783 </DOCNO>
Magnetic monopoles vs. Hopf defects in the Laplacian (Abelian) gauge


  We investigate the Laplacian Abelian gauge on the sphere S^4 in the
background of a single `t Hooft instanton. To this end we solve the eigenvalue
problem of the covariant Laplace operator in the adjoint representation. The
ground state wave function serves as an auxiliary Higgs field. We find that the
ground state is always degenerate and has nodes. Upon diagonalisation, these
zeros induce toplogical defects in the gauge potentials. The nature of the
defects crucially depends on the order of the zeros. For first-order zeros one
obtains magnetic monopoles. The generic defects, however, arise from zeros of
second order and are pointlike. Their topological invariant is the Hopf index
S^3 -> S^2. These findings are corroborated by an analysis of the Laplacian
gauge in the fundamental representation where similar defects occur. Possible
implications for the confinement scenario are discussed.

</DOC>
<DOC>
<DOCNO> 39957 </DOCNO>
TAC Proposal for Fundamental and Applied Research: Linac-Ring Type


  Main parameters of linac-ring type $phi$-factory proposed as the part of the
Turkic Accelerator Complex (TAC) in the framework of ATAM Science Sity Project
are discussed. Two sets of parameters, corresponding to E=130(260) MeV for
electron linac and E=2000(1000) MeV positron ring, are considered. It is swoun
that, in principle, L=10^(34)cm^(-2)s^(-1) can be achieved, which is more than
an order exceeds the design luminosity of the DA$Phi$NE. Parameters of the FEL
based on electron linac and synchrotron radiation sources based on the positron
ring are estimated.

</DOC>
<DOC>
<DOCNO> 80997 </DOCNO>
The Combination of Wilson Loops into $J^{PC}$ Operators in Lattice Pure


  To calculate the mass of glueballs with quantum number $J^{PC}$ in lattice
gauge theory by using Wilson loops, we discuss their combinations of Wilson
loops into irreducible representation of $O^{PC}$ group for arbitry-link wilson
loops. We present a general computational procedure for this combination which
is suitable for any finite groups.

</DOC>
<DOC>
<DOCNO> 68647 </DOCNO>
Flow equations in the light-front QCD: mass gap and confinement


  The light-front QCD is studied using the method of flow equations. Solving
the light-front gluon gap equation, the effective gluon mass is generated
dynamically. The effective interaction between static quark and antiquark,
generated through elimination of the quark-gluon minimal coupling by flow
equations, has the Coulomb, $1/q^2$, and confining, $1/q^4$, singular behavior.
Elimination of the quark-gluon coupling at small gluon momenta is governed by
the cutoff dependent, dynamical gluon mass, which makes this elimination
possible and provides such an enhancement at $q\sim 0$. The cutoff, which
regulates small light-front $x$ divergences, sets up a scale for the dynamical
gluon mass and the string tension in the $q\bar{q}$-potential. The mechanism of
confimenemet in the light-front frame is suggested, based on the singular
nature of the light-front gauge along the light-front $x$-axis.

</DOC>
<DOC>
<DOCNO> 117239 </DOCNO>
PARIS Interferometric Processor Analysis and Experimental Results:


  Several experimental results show that it is possible to extract useful phase
information from reflected GPS signals over the oceans. In this work we begin
the development of the theoretical background to account for these results and
fully understand the phenomena involved. This information will then be used to
define and carry out new experiments to evaluate the feasibility of using the
phase from reflected GPS signals for altimetric purposes and the advantages of
using interferometric combinations of the signals at different
frequencies---the PIP concept.
  We focus on the coherence properties of the signals, including the PIP
interferometric combination of phases in the different frequencies. In this
work we will concentrate on a static, 8 m high receiver (at least in regards to
the simulations), and an infinitely removed static source. As the ocean moves,
the received field will pick up a random phase. We want to understand the
behavior of this phase, as the goal is to carry out altimetric measurements
using phase ranging. We will also show that this random phase carries
geophysical information (intuitively, the bigger the significant wave height,
the larger the phase excursions).

</DOC>
<DOC>
<DOCNO> 40210 </DOCNO>
Physics at a Neutrino Factory


  In response to the growing interest in building a Neutrino Factory to produce
high intensity beams of electron- and muon-neutrinos and antineutrinos, in
October 1999 the Fermilab Directorate initiated two six-month studies. The
first study, organized by N. Holtkamp and D. Finley, was to investigate the
technical feasibility of an intense neutrino source based on a muon storage
ring. This design study has produced a report in which the basic conclusion is
that a Neutrino Factory is technically feasible, although it requires an
aggressive R&D program. The second study, which is the subject of this report,
was to explore the physics potential of a Neutrino Factory as a function of the
muon beam energy and intensity, and for oscillation physics, the potential as a
function of baseline.

</DOC>
<DOC>
<DOCNO> 116934 </DOCNO>
Development of the Low Energy Accelerator for Komac


  KAERI (Korea Atomic Energy Research Institute) has been performing the
project named KOMAC (Korea Multi-purpose Accelerator Complex) within the frame
work of national mid and long term nuclear research plan. The final objectives
of KOMAC is to build a 20-MW (1 GeV and 20 mA) cw (100% duty factor) proton
linear accelerator. As the first stage, the low energy accelerator up to 20 MeV
is being developed in KTF (KOMAC Test Facility). The low energy accelerator
consists of an injector, RFQ, CCDTL, and RF systems. The proton injector with
Duoplasmatron ion source has been developed, and the LEBT with solenoid lens is
under development. The RFQ linac that will accelerate a 20mA proton beam from
50keV to 3MeV has been designed and is being fabricated. The RF system for RFQ
is being developed, and the CCDTL up to 20MeV is being designed. The status of
the low energy accelerator will be presented.

</DOC>
<DOC>
<DOCNO> 9813 </DOCNO>
Half-quantum vortex and d-soliton in Sr$_2$RuO$_4$


  Assuming that the superconductivity in Sr$_2$RuO$_4$ is described by a planar
p-wave order parameter, we consider possible topological defects in
Sr$_2$RuO$_4$. In particular, it is shown that both of the ${\hat d}$-soliton
and half-quantum vortex can be created in the presence of the magnetic field
parallel to the $a$-$b$ plane. We discuss how one can detect the ${\hat
d}$-soliton and half-quantum vortex experimentally.

</DOC>
<DOC>
<DOCNO> 174497 </DOCNO>
Crossing the Dripline to 11N Using Elastic Resonance Scattering


  The level structure of the unbound nucleus 11N has been studied by 10C+p
elastic resonance scattering in inverse geometry with the LISE3 spectrometer at
GANIL, using a 10C beam with an energy of 9.0 MeV/u. An additional measurement
was done at the A1200 spectrometer at MSU. The excitation function above the
10C+p threshold has been determined up to 5 MeV. A potential-model analysis
revealed three resonance states at energies 1.27 (+0.18-0.05) MeV (Gamma=1.44
+-0.2 MeV), 2.01(+0.15-0.05) MeV, (Gamma=0.84 +-$0.2 MeV) and 3.75(+-0.05) MeV,
(Gamma=0.60 +-0.05 MeV) with the spin-parity assignments I(pi) =1/2+, 1/2- and
5/2+, respectively. Hence, 11N is shown to have a ground state parity inversion
completely analogous to its mirror partner, 11Be. A narrow resonance in the
excitation function at 4.33 (+-0.05) MeV was also observed and assigned
spin-parity 3/2-.

</DOC>
<DOC>
<DOCNO> 100916 </DOCNO>
Homogeneous symplectic manifolds with Ricci-type curvature


  We consider invariant symplectic connections $\nabla$ on homogeneous
symplectic manifolds $(M,\omega)$ with curvature of Ricci type. Such
connections are solutions of a variational problem studied by Bourgeois and
Cahen, and provide an integrable almost complex structure on the bundle of
almost complex structures compatible with the symplectic structure. If $M$ is
compact with finite fundamental group then $(M,\omega)$ is symplectomorphic to
$\P_n(\C)$ with a multiple of its K\"ahler form and $\nabla$ is affinely
equivalent to the Levi-Civita connection.

</DOC>
<DOC>
<DOCNO> 13622 </DOCNO>
Nuclear magnetic resonance spectrum of 31P donors in silicon quantum


  The influence of the electric field created by a gate potential of the
silicon quantum computer on the hyperfine interaction constant (HIC) is
obtained. The errors due to technological inaccuracy of location of donor atoms
under a gate are evaluated. The energy spectra of electron-nuclear spin system
of two interacting donor atoms with various values of HIC are calculated. The
presence of two pairs of anticrossing levels in the ground electronic state is
shown. Parameters of the structure at which errors rate can be greatly
minimized are found.

</DOC>
<DOC>
<DOCNO> 71734 </DOCNO>
LATTICEEASY: A Program for Lattice Simulations of Scalar Fields in an


  We describe a C++ program that we have written and made available for
calculating the evolution of interacting scalar fields in an expanding
universe. The program is particularly useful for the study of reheating and
thermalization after inflation. The program and its full documentation are
available on the Web at http://physics.stanford.edu/gfelder/latticeeasy/ . In
this paper we provide a brief overview of what the program does and what it is
useful for.

</DOC>
<DOC>
<DOCNO> 69765 </DOCNO>
Bulk Supersymmetry and Brane Cosmological Constant


  We consider a recent proposal to solve the cosmological constant problem
within the context of brane world scenarios with infinite volume extra
dimensions. In such theories bulk can be supersymmetric even if brane
supersymmetry is completely broken. We propose a setup where unbroken bulk
supersymmetry appears to protect the brane cosmological constant. This is due
to a non-trivial scalar potential in the bulk which implies a non-trivial
profile for a bulk scalar field. In the presence of the latter bulk
supersymmetry appears to be incompatible with non-vanishing brane cosmological
constant. Moreover, in this setup the corresponding domain wall interpolates
between an AdS and the Minkowski vacua, so that the weak energy condition is
not violated.

</DOC>
<DOC>
<DOCNO> 116740 </DOCNO>
The Proposed NLC Linac LLRF System


  The proposed Next Linear Collider (NLC) contains linac systems operating at
L,S,C, and X band. This paper describes a wideband modular low-level RF (LLRF)
system applicable for all NLC pulsed RF systems. High speed digital IF
techniques are used for both arbitrary klystron drive modulation and accurate
RF vector detection. Measurement of relative beam to RF phase, beam loading
compensation, and structure dipole modes for automated alignment are all
handled by the system. Modern signal processing techniques are also described.

</DOC>
<DOC>
<DOCNO> 169577 </DOCNO>
First Single Bubble Sonoluminescence in Dubna


  At the Institute in Physical-Technical Problems experiments on
sonoluminescence was started by our group at the beginning of 1998. The study
was focused at properties of the SBSL, and the aim was to find more optimum
conditions for a search for some recently predicted rare effects in SBSL-
process.

</DOC>
<DOC>
<DOCNO> 14033 </DOCNO>
Structural Phase Transition in the 2D Spin Dimer Compound SrCu2(BO3)2


  A displacive, 2nd order structural phase transition at Ts=395 K from space
group I`4 2 m below Ts to I 4/m c m above Ts has been discovered in the
two-dimensional spin dimer compound SrCu2(BO3)2. The temperature evolution of
the structure in both phases has been studied by X-ray diffraction and Raman
scattering, supplemented by differential scanning calorimetry and SQUID
magnetometry. The implications of this transition and of the observed phonon
anomalies in Raman scattering for spin-phonon and interlayer coupling in this
quantum spin system will be discussed.

</DOC>
<DOC>
<DOCNO> 152094 </DOCNO>
Perturbative and instanton corrections to the OPE of CPOs in N=4 SYM_4


  We study perturbative and instanton corrections to the Operator Product
Expansion of the lowest weight Chiral Primary Operators of N=4 SYM_4. We
confirm the recently observed non-renormalization of various operators (notably
of the double-trace operator with dimension 4 in the 20 irrep of SU(4)), that
appear to be unprotected by unitarity restrictions. We demonstrate the
splitting of the free-field theory stress tensor and R-symmetry current in
supermultiplets acquiring different anomalous dimensions in perturbation theory
and argue that certain double-trace operators also undergo a perturbative
splitting into operators dual to string and two-particle gravity states
respectively. The instanton contributions affect only those double-trace
operators that acquire finite anomalous dimensions at strong coupling. For the
leading operators of this kind, we show that the ratio of their anomalous
dimensions at strong coupling to the anomalous dimensions due to instantons is
the same number.

</DOC>
<DOC>
<DOCNO> 100156 </DOCNO>
Ribbon-moves of 2-knots: the Farber-Levine pairing and the


  Let K and K' be 2-knots. Suppose that K and K' are ribbon-move equivalent.
Then the Farber-Levine pairing for K is equivalent to that for K' and the
(Z-)torsion part of the first Alexander module of $K$ is isomorphic to that of
K' as Z[Z] modules.
  Let K be a 2-knot which is ribbon-move equivalent to the trivial knot. Then
the Atiyah-Patodi-Singer-Casson-Gordon-Ruberman Q/Z-valued
\widetilde\eta-invariants of K for Z_d is zero. (d is a natural number. d>2.).

</DOC>
<DOC>
<DOCNO> 100423 </DOCNO>
On a theorem of Henri Cartan concerning the equivaraint cohomology


  Suppose G is a compact Lie group and N is a closed normal subgroup of G
acting freely on a smooth manifold X. The Cartan theorem alluded to in the
title postulates the existence of a natural isomorphism between the
G-equivariant cohomology X and the G/N-equivariant cohomology of X/N.
 In this note we use J. Kalkman's explicit isomorphism between the Cartan and
Weil models of equivariant cohomology to show that 1) Cartan's theorem is a
simple consequence of Chern-Weil's transgression formula and 2) explicitly
describe this isomorphism at the cochain level.

</DOC>
<DOC>
<DOCNO> 178590 </DOCNO>
On the effects of the final state interaction in the


  The role of the final state interactions (FSI) in the inclusive quasi-elastic
disintegration of the deuteron is investigated treating the two-nucleon final
state within the exact continuum solutions of the non-relativistic Schroedinger
equation, as well as within the Glauber multiple scattering approach. It is
shown that for values of the Bjorken scaling variable $x_{Bj}\simeq 1$ both
approaches provide similar results, unless the case $x_{Bj}\gtrsim 1$, where
they appreciably disagree. It is demonstrated that present experimental data,
which are mostly limited to a region of four-momentum transfer ($Q^2 \lesssim 4
(GeV/c)^2$) where the Center-of-Mass energy of the final state is below the
pion threshold production, can be satisfactorily reproduced by the approach
based on the exact solution of the Schroedinger equation and not by the Glauber
approach. It is also pointed out that the latter, unlike the former, does not
satisfy the inelastic Coulomb sum rule, the violation being of the order of
about 20%.

</DOC>
<DOC>
<DOCNO> 119258 </DOCNO>
Irradiation and mass transfer in low-mass compact binaries


  We study the reaction of low-mass stars to anisotropic irradiation and its
importance for the long-term evolution of compact binaries binaries. We show by
means of a simple homology model that if the energy outflow through the surface
layers of a low-mass main sequence star is blocked over a fraction s_eff < 1 of
its surface it will inflate only modestly and that the maximum contribution to
mass transfer is s_eff times what one obtains in the isotropic case. The
duration of this mass transfer phase is roughly -0.1 ln(1-s_eff) times the
thermal time scale of the convective envelope. Numerical computations confirm
these results. Second, we present a simple analytic one-zone model for
computing the blocking effect by irradiation which gives results in acceptable
quantitative agreement with detailed numerical computations. Third, we show
that unless mass transfer is strongly enhanced by consequential angular
momentum losses, cataclysmic variables are stable against mass transfer if the
mass of the main sequence donor is less than about 0.7 solar masses. Otherwise
systems may be unstable, subject to the efficiency of irradiation. We argue
that low-mass X-ray binaries are even less susceptible to this instability. In
case of instability, mass transfer must evolve through a limit cycle in which
phases of high mass transfer alternate with phases of small (or no) mass
transfer.

</DOC>
<DOC>
<DOCNO> 69644 </DOCNO>
Magnetic string contribution to hadron dynamics in QCD


  Dynamics of a light quark in the field of static source (heavy-light meson)
is studied using the nonlinear Dirac equation, derived recently. Special
attention is paid to the contribution of magnetic correlators and it is found
that it yields a significant increase of string tension at intermediate
distances. The spectrum of heavy-light mesons is computed with account of this
contribution and compared to experimental and lattice data.

</DOC>
<DOC>
<DOCNO> 14088 </DOCNO>
Dynamics of a three terminal mechanically flexible tunneling contact


  The dynamics of a nanoelectromechanical system in the form of a
three-terminal tunneling device is studied by analytical and numerical methods.
The main results are the existence of bistable stationary states resulting in
directly detectable chaotic behavior.

</DOC>
<DOC>
<DOCNO> 69971 </DOCNO>
Instanton Effects on the Role of the Low-Energy Theorem for the Scalar


  Instanton contributions to the Laplace sum-rules for correlation functions of
scalar gluonic currents are calculated. It is demonstrated that the instanton
contributions consist of an instanton continuum that contributes to all
sum-rules and a (scale-independent) portion which makes a unique contribution
to the sum-rule containing the low-energy theorem. These instanton
contributions are found to diminish the role of the low-energy theorem in the
sum-rules, significantly increasing the resulting mass bounds for the ground
state of scalar gluonium.

</DOC>
<DOC>
<DOCNO> 116655 </DOCNO>
"Back-of-the-envelope" wind and altitude correction for 100 metre sprint


  A simple algebraic expression is presented to correct men's and women's 100
metre sprint times for ambient wind and altitude effects. The simplified
formula is derived from a more complicated equation of motion used to model the
athlete's velocity as a function of time (the velocity curve). This method
predicts adjustments to 0-wind and 0-altitude equivalents, which are in
excellent agreement to other estimates presented in the literature. The
expression is easily programmable on any computer, and could conveniently be
used by coaches, meet directors, or the media to assess the performance of
athletes and the quality of a race immediately following the event.

</DOC>
<DOC>
<DOCNO> 67653 </DOCNO>
Phases of Chiral Gauge Theories


  We discuss the behavior of two non-supersymmetric chiral SU(N) gauge
theories, involving fermions in the symmetric and antisymmetric two-index
tensor representations respectively. In addition to global anomaly matching, we
employ a recently proposed inequality constraint on the number of effective low
energy (massless) degrees of freedom of a theory, based on the thermodynamic
free energy. Several possible zero temperature phases are consistent with the
constraints. A simple picture for the phase structure emerges if these theories
choose the phase, consistent with global anomaly matching, that minimizes the
massless degree of freedom count defined through the free energy. This idea
suggests that confinement with the preservation of the global symmetries
through the formation of massless composite fermions is in general not
preferred. While our discussion is restricted mainly to bilinear condensate
formation, higher dimensional condensates are considered for one case. We
conclude by commenting briefly on two related supersymmetric chiral theories.

</DOC>
<DOC>
<DOCNO> 71089 </DOCNO>
Radiatively Induced Neutrino Masses and Oscillations in an


  We have constructed an $SU(3)_L \times U(1)_N$ gauge model utilizing an
$U(1)_{L^\prime}$ symmetry, where $L^\prime$ = $L_e-L_\mu-L_\tau$, which
accommodates tiny neutrino masses generated by $L^\prime$-conserving one-loop
and $L^\prime$-breaking two-loop radiative mechanisms. The generic smallness of
two-loop radiative effects compared with one-loop radiative effects describes
the observed hierarchy of $\Delta m_{atm}^2$ $\gg$ $\Delta m_\odot^2$. A key
ingredient for radiative mechanisms is a charged scalar ($h^+$) that couples to
charged lepton-neutrino pairs and $h^+$ together with the standard Higgs scalar
($\phi$) can be unified into a Higgs triplet as ($\phi^0$, $\phi^-$,
$h^+$)$^T$. This assignment in turn requires lepton triplets ($\psi_L^i$) with
heavy charged leptons ($\kappa_L^{+i}$) as the third member:
$\psi_L^i=(\nu^i_L,\ell^i_L,\kappa^{+i}_L)^T$, where $i$ ($=1,2,3$) denotes
three families. It is found that our model is relevant to yield quasi-vacuum
oscillations for solar neutrinos.

</DOC>
<DOC>
<DOCNO> 152622 </DOCNO>
Excited TBA Equations I: Massive Tricritical Ising Model


  We consider the massive tricritical Ising model M(4,5) perturbed by the
thermal operator phi_{1,3} in a cylindrical geometry and apply integrable
boundary conditions, labelled by the Kac labels (r,s), that are natural
off-critical perturbations of known conformal boundary conditions. We derive
massive thermodynamic Bethe ansatz (TBA) equations for all excitations by
solving, in the continuum scaling limit, the TBA functional equation satisfied
by the double-row transfer matrices of the A_4 lattice model of Andrews, Baxter
and Forrester (ABF) in Regime III. The complete classification of excitations,
in terms of (m,n) systems, is precisely the same as at the conformal
tricritical point. Our methods also apply on a torus but we first consider
(r,s) boundaries on the cylinder because the classification of states is simply
related to fermionic representations of single Virasoro characters
chi_{r,s}(q). We study the TBA equations analytically and numerically to
determine the conformal UV and free particle IR spectra and the connecting
massive flows. The TBA equations in Regime IV and massless RG flows are studied
in Part II.

</DOC>
<DOC>
<DOCNO> 170285 </DOCNO>
Universal Manipulation of a Single Qubit


  We find the optimal universal way of manipulating a single qubit,
|psi(theta,phi)>, such that (theta,phi)->(theta-k,phi-l). Such optimal
transformations fall into two classes. For 0 =< k =< pi/2 the optimal map is
the identity and the fidelity varies monotonically from 1 (for k=0) to 1/2 (for
k=pi/2). For pi/2 =< k =< pi the optimal map is the universal-NOT gate and the
fidelity varies monotonically from 1/2 (for k=pi/2) to 2/3 (for k=pi). The
fidelity 2/3 is equal to the fidelity of measurement. It is therefore rather
surprising that for some values of k the fidelity is lower than 2/3.

</DOC>
<DOC>
<DOCNO> 84166 </DOCNO>
Vacuum Polarization and Energy Conditions at a Planar Frequency


  The form of the vacuum stress-tensor for the quantized scalar field at a
dielectric to vacuum interface is studied. The dielectric is modeled to have an
index of refraction that varies with frequency. We find that the stress-tensor
components, derived from the mode function expansion of the Wightman function,
are naturally regularized by the reflection and transmission coefficients of
the mode at the boundary. Additionally, the divergence of the vacuum energy
associated with a perfectly reflecting mirror is found to disappear for the
dielectric mirror at the expense of introducing a new energy density near the
surface which has the opposite sign. Thus the weak energy condition is always
violated in some region of the spacetime. For the dielectric mirror, the mean
vacuum energy density per unit plate area in a constant time hypersurface is
always found to be positive (or zero) and the averaged weak energy condition is
proven to hold for all observers with non-zero velocity along the normal
direction to the boundary. Both results are found to be generic features of the
vacuum stress-tensor and not necessarily dependent of the frequency dependence
of the dielectric.

</DOC>
<DOC>
<DOCNO> 150523 </DOCNO>
Simulated Annealing for Topological Solitons


  The search for solutions of field theories allowing for topological solitons
requires that we find the field configuration with the lowest energy in a given
sector of topological charge. The standard approach is based on the numerical
solution of the static Euler-Lagrange differential equation following from the
field energy. As an alternative, we propose to use a simulated annealing
algorithm to minimize the energy functional directly. We have applied simulated
annealing to several nonlinear classical field theories: the sine-Gordon model
in one dimension, the baby Skyrme model in two dimensions and the nuclear
Skyrme model in three dimensions. We describe in detail the implementation of
the simulated annealing algorithm, present our results and get independent
confirmation of the studies which have used standard minimization techniques.

</DOC>
<DOC>
<DOCNO> 102152 </DOCNO>
Apollonian Circle Packings: Geometry and Group Theory I. The Apollonian


  Apollonian circle packings arise by repeatedly filling the interstices
between four mutually tangent circles with further tangent circles. The {\em
Descartes equation} relates the radii of curvature of any four mutually tangent
circles: $(a_1^2 + a_2^2 + a_3^2 + a_4^2) = 1/2(a_1+ a_2 + a_3 +a_4)^2 = 0.$ We
establish a generalization of the Descartes equation which similarly relates
the radii of curvature $\times$ the center of the circles, where the circle
center is regarded as a complex number, and give a further generalization that
characterizes {\em Descartes configurations} consisting of four mutually
tangent circles with disjoint interiors. This allows us to describe such
configurations using curvature-center coordinates. There are two natural group
actions on Descartes configurations: the group M\"{o}b(2) of conformal
transformations, and a group $Iso^\uparrow(Q_2)$ that it acts linearly on the
left on Descartes quadruples given in curvature-center coordinates. We study
the relation between the M\"{o}b(2)-action and the $Iso^\uparrow(Q_2)$-action,
showing that the M\"{o}b(2)-action corresponds to a linear action on the right
in an extension of curvature-center coordinates. We conclude that these actions
are different, but mutually commute.

</DOC>
<DOC>
<DOCNO> 12882 </DOCNO>
Substrate-mediated interaction on Ag(111) surfaces from first principles


  When two or more atoms bind to a solid surface, the substrate can mediate an
interaction between them. In this paper, we use density-functional theory to
quantify the substrate-mediated pair interaction between two adatoms on a
compressively strained Ag(111) surface and on unstrained Ag(111). On the
strained surface, the elastic interaction is significant over the short range
and leads to a net attraction between two adatoms. However, at the longest
distances probed, the interaction is primarily electronic and repulsive. The
repulsion can be as strong at 50 meV, and it forms a ring-like structure around
an atom. On unstrained Ag(111), the interaction is primarily electronic in
origin and it is weak relative to the interaction found on the strained
surface. We calculate the energy barrier for an isolated atom to diffuse in
each of these systems. For the strained surface, the magnitude of the diffusion
barrier is comparable to that of the adsorbate interaction. We discuss the
implications of our findings for growth at surfaces.

</DOC>
<DOC>
<DOCNO> 85260 </DOCNO>
The radial supersymmetry of the (d+1)-dimensional relativistic rotating


  We study the supersymmetry of the radial problems of the models of quantum
relativistic rotating oscillators in arbitrary dimensions, defined as
Klein-Gordon fields in backgrounds with deformed anti-de Sitter metrics. It is
pointed out that the shape invariance of the supersymmetric partner radial
potentials leads to simple operators forms of the Rodrigues formulas for the
normalized radial wave functions.

</DOC>
<DOC>
<DOCNO> 8481 </DOCNO>
Magnetic Field of an In-Plane Vortex Inside and Outside a Layered


  In the present work we study an anisotropic layered superconducting film of
finite thickness. The film surfaces are considered parallel to the $bc$ face of
the crystal. The vortex lines are oriented perpendicular to the film surfaces
and parallel to the superconducting planes. We calculate the local field and
the London free energy for this geometry. Our calculation is a generalization
of previous works where the sample is taken as a semi-infinite superconductor.
As an application of this theory we investigate the flux spreading at the
superconducting surface.

</DOC>
<DOC>
<DOCNO> 122646 </DOCNO>
Alkali Metals and the Color of Brown Dwarfs


  I summarize some of the consequences for the optical and very-near-infrared
spectra of T dwarfs (in particular) and brown dwarfs (in general) of their
possible dominance by the neutral alkali metal lines. As a byproduct of this
study, I estimate the true optical color of ``brown'' dwarfs.

</DOC>
<DOC>
<DOCNO> 178750 </DOCNO>
Quark Models of Baryon Masses and Decays


  The application of quark models to the spectra and strong and electromagnetic
couplings of baryons is reviewed. This review focuses on calculations which
attempt a global description of the masses and decay properties of baryons,
although recent developments in applying large N_c QCD and lattice QCD to the
baryon spectrum are described. After outlining the conventional
one-gluon-exchange picture, models which consider extensions to this approach
are contrasted with dynamical quark models based on Goldstone-boson exchange
and an algebraic collective-excitation approach. The spectra and
electromagnetic and strong couplings that result from these models are compared
with the quantities extracted from the data and each other, and the impact of
various model assumptions on these properties is emphasized. Prospects for the
resolution of the important issues raised by these comparisons are discussed.

</DOC>
<DOC>
<DOCNO> 150354 </DOCNO>
Supersymmetric Duality Rotations


  We derive N = 1, 2 superfield equations as the conditions for a (nonlinear)
theory of one abelian N = 1 or N = 2 vector multiplet to be duality invariant.
The N = 1 super Born-Infeld action is a particular solution of the
corresponding equation. A family of duality invariant nonlinear N = 1
supersymmetric theories is described. We present the solution of the N = 2
duality equation which reduces to the N = 1 Born-Infeld action when the (0,1/2)
part of N = 2 vector multiplet is switched off. We also propose a constructive
perturbative scheme to compute duality invariant N = 2 superconformal actions.

</DOC>
<DOC>
<DOCNO> 121016 </DOCNO>
Supernovae and the IGM


  An energetic argument implies that a galaxy like the Milky Way is blowing a
powerful wind that carries away most of the heavy elements currently
synthesized and has impacted the IGM out to at least 180 kpc. Rich clusters of
galaxies appear to be closed systems in which most heavy elements are ejected
from galaxies. More supernovae are required than the yield of core-collapse SNe
from a Salpeter IMF. X-ray observations imply that the IGM in groups and
clusters as been strongly preheated. SNe probably cannot supply the required
energy, which must come from AGN.

</DOC>
<DOC>
<DOCNO> 100365 </DOCNO>
Essential self-adjointness of symmetric linear relations associated to


  The purpose of this note is to present several criteria for essential
self-adjointness. The method is based on ideas due to Shubin.
  This note is divided into two parts. The first part deals with symmetric
first order systems on the line in the most general setting. Such a symmetric
first order system of differential equations gives rise naturally to a
symmetric linear relation in a Hilbert space. In this case even regularity is
nontrivial. We will announce a regularity result and discuss criteria for
essential self-adjointness of such systems. This part is based on joint work
with Mark Malamud. Details will be published elsewhere.
  In the second part we consider a complete Riemannian manifold, $M$, and a
first order differential operator, $D:\cinfz{E}\to \cinfz{F}$, acting between
sections of the hermitian vector bundles $E,F$. Moreover, let $V:\cinf{E}\to
L^{\infty}_{\loc}(E)$ be a self-adjoint zero order differential operator. We
give a sufficient condition for the Schr\"odinger operator $H=D^tD+V$ to be
essentially self-adjoint. This generalizes recent work of I. Oleinik
\cite{Ole:ESA,Ole:CCQ,Ole:ESAG}, M. Shubin \cite{Shu:CQC,Shu:ESA}, and M.
Braverman \cite{Bra:SAS}.

</DOC>
<DOC>
<DOCNO> 84296 </DOCNO>
Einstein-Yang-Mills Isolated Horizons: Phase Space, Mechanics, Hair and


  The concept of "Isolated Horizon" has been recently used to provide a full
Hamiltonian treatment of black holes. It has been applied successfully to the
cases of {\it non-rotating}, {\it non-distorted} black holes in Einstein
Vacuum, Einstein-Maxwell and Einstein-Maxwell-Dilaton Theories. In this note,
it is investigated the extent to which the framework can be generalized to the
case of non-Abelian gauge theories where `hairy black holes' are known to
exist. It is found that this extension is indeed possible, despite the fact
that in general, there is no `canonical normalization' yielding a preferred
Horizon Mass. In particular the zeroth and first laws are established for all
normalizations. Colored static spherically symmetric black hole solutions to
the Einstein-Yang-Mills equations are considered from this perspective. A
canonical formula for the Horizon Mass of such black holes is found. This
analysis is used to obtain nontrivial relations between the masses of the
colored black holes and the regular solitonic solutions in Einstein-Yang-Mills
theory. A general testing bed for the instability of hairy black holes in
general non-linear theories is suggested. As an example, the embedded Abelian
magnetic solutions are considered. It is shown that, within this framework, the
total energy is also positive and thus, the solutions are potentially unstable.
Finally, it is discussed which elements would be needed to place the Isolated
Horizons framework for Einstein-Yang-Mills theory in the same footing as the
previously analyzed cases. Motivated by these considerations and using the fact
that the Isolated Horizons framework seems to be the appropriate language to
state uniqueness and completeness conjectures for the EYM equations --in terms
of the horizon charges--, two such conjectures are put forward.

</DOC>
<DOC>
<DOCNO> 178861 </DOCNO>
Electromagnetic Structure of Few-Nucleon Systems: a Critical Review


  Our current understanding of the structure of nuclei with up to A=8,
including energy spectra, electromagnetic form factors, and capture reactions,
is critically reviewed within the context of a realistic approach to nuclear
dynamics based on two- and three-nucleon interactions and associated
electromagnetic currents.

</DOC>
<DOC>
<DOCNO> 8239 </DOCNO>
Path-integral Monte Carlo Simulations without the Sign Problem:


  The multilevel blocking algorithm recently proposed as a possible solution to
the sign problem in path-integral Monte Carlo simulations has been extended to
systems with long-ranged interactions along the Trotter direction. As an
application, new results for the real-time quantum dynamics of the spin-boson
model are presented.

</DOC>
<DOC>
<DOCNO> 13509 </DOCNO>
Phase Fluctuations and Vortex Lattice Melting in Triplet


  Assuming that the order parameter corresponds to an equal spin triplet
pairing symmetry state, we calculate the effect of phase fluctuations in
quasi-one-dimensional superconductors at high magnetic fields applied along the
y (b') axis. We show that phase fluctuations can destroy the theoretically
predicted triplet reentrant superconducting state, and that they are
responsible for melting the magnetic field induced Josephson vortex lattice
above a magnetic field dependent melting temperature Tm.

</DOC>
<DOC>
<DOCNO> 121409 </DOCNO>
Detection of spiral magnetic fields in two flocculent galaxies


  Two flocculent galaxies NGC 3521 and NGC 5055 has been observed at 10.55GHz
with the Effelsberg 100m telescope. In both cases polarized emission reveals
substantial radial component of regular magnetic field - similar to that in
grand-designed spirals. Comparison with H_alpha distribution obtained at Lowell
Observatory is presented. Polarization models discussed, support modern
non-standard dynamo concepts for magnetic field generation in galaxies.

</DOC>
<DOC>
<DOCNO> 70455 </DOCNO>
D and J/psi production from deconfined matter in relativistic heavy ion


  We study the production of the D and J/psi mesons from deconfined quark
matter at CERN SPS energy. Using the MICOR microscopical coalescence model we
determine the transverse momentum spectra of these charm mesons. We predict the
slopes of their transverse momentum spectra in Pb+Pb collision at 158
GeV/nucleon beam energy.

</DOC>
<DOC>
<DOCNO> 10573 </DOCNO>
New features of dislocation structures arising from lattice discreteness


  New aspects of a relation between lattice and dislocation structures are
examined within a physically transparent theoretical scheme. Predicted features
originating from the lattice discreteness include: (i) multiple core
dislocation structures and (ii) their dependence on the position of the
dislocation axis. These effects, which in principle can be observed directly
and may also manifest themselves in dislocation motion or/and transformation
(cross-slip) characteristics, are very general and present in any crystal in
which they may be more or less pronounced depending on the material.

</DOC>
<DOC>
<DOCNO> 178555 </DOCNO>
Discussing the possibility of observation of parity violation in heavy


  It was recently argued that in heavy ion collision the parity could be
broken. This Note addresses the question of possibility of the experimental
detection of the effect. We discuss how parity violating effects would modify
the final particle distributions and how one could construct variables
sensitive to the effect, and which measurement would be the (most) conclusive.
Discussing different observables we also discuss the question if the
``signals'' can be faked by ``conventional'' effects (such as anisotropic flow,
etc.) and make estimates of the signals.

</DOC>
<DOC>
<DOCNO> 178839 </DOCNO>
Nuclear fragmentation: sampling the instabilities of binary systems


  We derive stability conditions of Asymmetric Nuclear Matter ($ANM$) and
discuss the relation to mechanical and chemical instabilities of general
two-component systems. We show that the chemical instability may appear as an
instability of the system against isoscalar-like rather than isovector-like
fluctuations if the interaction between the two constituent species has an
attractive character as in the case of $ANM$. This leads to a new kind of
liquid-gas phase transition, of interest for fragmentation experiments with
radioactive beams.

</DOC>
<DOC>
<DOCNO> 170043 </DOCNO>
Separability of Density Matrices and Conditional Information


  We give necessary and sufficient conditions under which a density matrix
acting on a two-fold tensor product space is separable. Our conditions are
given in terms of quantum conditional information transmission.

</DOC>
<DOC>
<DOCNO> 102165 </DOCNO>
Helly-type Theorems for Plane Convex Curves


  Families of translates and homothets of strictly convex curves are proven to
possess Helly-type properties generalizing those of a circle. Weaker results
are shown for arbitrary convex curves.

</DOC>
<DOC>
<DOCNO> 118595 </DOCNO>
Cosmic Microwave Background at low frequencies


  The next generation low-frequency radio telescopes may probe cosmological
models by means of observations of the cosmic microwave background (CMB). I
discuss the prospects for observations of CMB imprints - recombination lines
from the epoch of recombination, \mu distortions and angular temperature
anisotropies - at low frequencies. A future low-frequency radio telescope, like
the proposed SKA, may be capable of attempting some difficult CMB measurements
because of the large collecting area and large element numbers; however, this
will require a telescope design that will allow specialized calibration
strategies and will give emphasis to the control of spurious responses.

</DOC>
<DOC>
<DOCNO> 122176 </DOCNO>
XMM-Newton observations of NGC 253: Resolving the emission components in


  The high XMM-Newton throughput allows a detailed investigation of the
spatial, spectral and variability properties of the extended and point source
emission of the starburst galaxy NGC 253 simultaneously. We characterize the
brightest sources by their hardness ratios, detect a bright X-ray transient,
and show the spectrum and light curve of the brightest point source, most
likely a black-hole X-ray binary. The unresolved emission of two disk regions
can be modeled by two thin thermal plasma components of 0.13 and 0.4 keV plus
residual harder emission, with the lower temperature component originating from
above the disk, the nuclear spectrum by a three temperature plasma (~0.6, 0.9,
and 6 keV) with the higher temperatures increasingly absorbed. The high
temperature component most likely originates from the starburst nucleus. No
non-thermal component, that would point at a significant contribution from an
active nucleus (AGN), is needed. Assuming that type IIa supernova remnants
(SNRs) are mostly responsible for the E>4 keV emission, the detection with EPIC
of the 6.7 keV line allows us to estimate a supernova rate within the nuclear
starburst of 0.2 yr^-1. RGS spectra and EPIC images reveal that the
limb-brightening of the plume is mostly seen in higher ionization emission
lines, while in the lower ionization lines, and below 0.5 keV, the plume is
more homogeneously structured. (abridged)

</DOC>
<DOC>
<DOCNO> 117935 </DOCNO>
Dynamical and chemical evolution of gas-rich dwarf galaxies


  We study the effect of a single, instantaneous starburst on the dynamical and
chemical evolution of a gas-rich dwarf galaxy, whose potential well is
dominated by a dark matter halo. We follow the dynamical and chemical evolution
of the ISM by means of an improved 2-D hydrodynamical code coupled with
detailed chemical yields originating from type II SNe, type Ia SNe and single
low and intermediate mass stars (IMS). In particular we follow the evolution of
the abundances of H, He, C, N, O, Mg, Si and Fe. We find that for a galaxy
resembling IZw18, a galactic wind develops as a consequence of the starburst
and it carries out of the galaxy mostly the metal-enriched gas. In addition, we
find that different metals are lost differentially in the sense that the
elements produced by type Ia SNe are more efficiently lost than others. As a
consequence of that we predict larger [$\alpha$/Fe] ratios for the gas inside
the galaxy than for the gas leaving the galaxy. A comparison of our predicted
abundances of C, N, O and Si in the case of a burst occurring in a primordial
gas shows a very good agreement with the observed abundances in IZw18 as long
as the burst has an age of $\sim 31$ Myr and IMS produce some primary nitrogen.
However, we cannot exclude that a previous burst of star formation had occurred
in IZw18 especially if the preenrichment produced by the older burst was lower
than $Z=0.01$ Z$_{\odot}$. Finally, at variance with previous studies, we find
that most of the metals reside in the cold gas phase already after few Myr.
This result is mainly due to the assumed low SNII heating efficiency, and
justifies the generally adopted homogeneous and instantaneous mixing of gas in
chemical evolution models.

</DOC>
<DOC>
<DOCNO> 39948 </DOCNO>
Central and Forward Inclusive Jets at the Tevatron


  We report on a new measurement of the rapidity dependence of the inclusive
jet production cross section in pbar p collisions at sqrt(s)=1.8 TeV using 92
pb^-1 of data collected by the DZero detector at the Tevatron collider. The
differential cross sections, d^2sigma/(dEt deta), are presented as a function
of jet transverse energy (Et) in five pseudorapidity (eta) intervals, up to
|eta|=3, significantly extending previous CDF and DZero measurements beyond
|eta|=0.7. The extended range of the measurement should provide greater
discrimination among different parton distribution functions. We also discuss
previous measurements of the inclusive jet cross sections made by the two
collider experiments at central pseudorapidities up to |eta|=0.7. Finally, we
present recent measurements from the CDF and DZero experiments of the ratio of
central inclusive cross sections from two center-of-mass energies, 0.63 TeV and
1.8 TeV, as a function of jet Xt. Experimental results are compared to
next-to-leading order QCD predictions.

</DOC>
<DOC>
<DOCNO> 169847 </DOCNO>
Theory of the Microscopic Maser Phase Transitions


  Phase diagrams of the micromaser system are mapped out in terms of the
physical parameters at hand like the atom cavity transit time, the atom-photon
frequency detuning, the number of thermal photons and the probability for a
pump atom to be in its excited state. Critical fluctuations are studied in
terms of correlation measurements on atoms having passed through the micromaser
or on the microcavity photons themselves. At sufficiently large values of the
detuning we find a ``twinkling'' mode of the micromaser system. Detailed
properties of the trapping states are also presented.

</DOC>
<DOC>
<DOCNO> 9039 </DOCNO>
Unusual magnetic relaxation behavior in La0.5Ca0.5MnO3


  We present an extensive study of the time dependence of the magnetization in
a polycrystalline and low temperature charge ordered La0.5Ca0.5MnO3 sample.
After application and removal of a 5 T magnetic field, a systematic variation
of the magnetic relaxation rate from 10 K to 245 K was found. At 195 K, the
magnetization decreases in a very short time and after that it increases slowly
as a function of time. Moreover, between 200 and 245 K, an increase in
magnetization, above the corresponding value just after removing the 5 T
magnetic field, was measured. This unusual behavior was tested in several other
relaxation procedures. PACS: 70, 74.25 Ha, 75.60.-d, 76.60.Es

</DOC>
<DOC>
<DOCNO> 101612 </DOCNO>
Covering properties of meromorphic functions, negative curvature and


  Every nonconstant meromorphic function in the plane univalently covers
spherical discs of radii arbitrarily close to arctan(sqrt 8) ~ 70^\circ 32'.
If in addition all critical points of the function are multiple, then a
similar statement holds with pi/2. These constants are the best possible. The
proof is based on the consideration of negatively curved singular surfaces
associated with meromorphic functions.

</DOC>
<DOC>
<DOCNO> 101409 </DOCNO>
Kahler-Einstein metrics on log del Pezzo surfaces in weighted projective


  We determine the complete list of anticanonically embedded quasi smooth log
del Pezzo surfaces in weighted projective 3-spaces. We prove that many of these
admit a K\"ahler-Einstein metric and most of them do not have tigers.

</DOC>
<DOC>
<DOCNO> 71494 </DOCNO>
Properties of color singlet chain states in $e^+e^-$ annihilation


  We use the method of the color effective Hamiltonian to study the structure
of color singlet chain states in $N_c=3$ and in the large $N_c$ limit. In order
to obtain their total fraction when $N_c$ is finite, we illustrate how to
orthogonalize these non-orthogonal states. We give numerical results for the
fraction of orthogonalized states in $e^+e^-\to q\bar{q}gg$. With the help of a
diagram technique, we derive their fraction up to $O(1/N_c^2)$ for the general
multigluon process. For large $N_c$ the singlet chain states correspond to
well-defined color topologies. Therefore we may expect that the fraction of
non-color-singlet-chain states is an estimate of the fraction of events where
color reconnection is possible. In the case of soft gluon bremsstrahlung, we
give an explicit form for the color effective Hamiltonian which leads to the
dipole cascade formulation for parton showering in leading order in $N_c$. The
next-to-leading order corrections are also given for $e^+e^-\to q\bar{q}g_1g_2$
and $e^+e^-\to q\bar{q}g_1g_2g_3$.

</DOC>
<DOC>
<DOCNO> 151824 </DOCNO>
Symmetry transform in the Faddeev-Jackiw quantization of dual models


  We study the presence of symmetry transformations in the Faddeev-Jackiw
approach for constrained systems. Our analysis is based in the case of a
particle submitted to a particular potential which depends on an arbitrary
function. The method is implemented in a natural way and symmetry generators
are identified. These symmetries permit us to obtain the absent elements of the
sympletic matrix which complement the set of Dirac brackets of such a theory.
The study developed here is applied in two different dual models. First, we
discuss the case of a two-dimensional oscillator interacting with an
electromagnetic potential described by a Chern-Simons term and second the
Schwarz-Sen gauge theory, in order to obtain the complete set of non-null Dirac
brackets and the correspondent Maxwell electromagnetic theory limit.

</DOC>
<DOC>
<DOCNO> 7629 </DOCNO>
Roton Instability of the Spin Wave Excitation in the Fully Polarized


  We consider the effect of interactions on electrons confined to two
dimensions at Landau level filling $\nu=2$, with the specific aim to determine
the range of parameters where the fully polarized state is stable. We calculate
the charge and the spin density collective modes in random phase approximation
(RPA) including vertex corrections (also known as time dependent Hartree Fock),
and treating the Landau level mixing accurately within the subspace of a single
particle hole pair. It is found that the spin wave excitation mode of the fully
polarized state has a roton minimum which deepens as a result of the
interaction induced Landau level mixing, and the energy of the roton vanishes
at a critical Zeeman energy signaling an instability of the fully polarized
state at still lower Zeeman energies. The feasibility of the experimental
observation of the roton minimum in the spin wave mode and its softening will
be discussed. The spin and charge density collective modes of the unpolarized
state are also considered, and a phase diagram for the $\nu =2$ state as a
function of $r_{S}$ and the Zeeman energy is obtained.

</DOC>
<DOC>
<DOCNO> 12202 </DOCNO>
The Kondo Effect in the Unitary Limit


  We observe a strong Kondo effect in a semiconductor quantum dot when a small
magnetic field is applied. The Coulomb blockade for electron tunneling is
overcome completely by the Kondo effect and the conductance reaches the
unitary-limit value. We compare the experimental Kondo temperature with the
theoretical predictions for the spin-1/2 Anderson impurity model. Excellent
agreement is found throughout the Kondo regime. Phase coherence is preserved
when a Kondo quantum dot is included in one of the arms of an Aharonov-Bohm
ring structure and the phase behavior differs from previous results on a
non-Kondo dot.

</DOC>
<DOC>
<DOCNO> 122768 </DOCNO>
Classification and Redshift Estimation in Multi-Color Surveys


  We present a photometric method for identifying stars, galaxies and quasars
in multi-color surveys and estimating multi-color redshifts for the
extragalactic objects. We use a library of >65000 color templates for
comparison with observed objects. The method was originally developed for the
Calar Alto Deep Imaging Survey (CADIS), but is now used in a variety of survey
projects. We checked its performance by spectroscopy of CADIS objects, where it
provides high reliability (6 mistakes among 151 objects with R<24), especially
for the quasar selection, and redshifts accurate within sigma_z = 0.03 for
galaxies and sigma_z = 0.1 for quasars. For an optimization of future surveys,
a few model surveys are compared, which use the same amount of telescope time
but different filter sets. In summary, medium-band surveys perform superior to
broad-band surveys although they collect less photons. A full account of this
work is already in print.

</DOC>
<DOC>
<DOCNO> 9880 </DOCNO>
Effects of Random Biquadratic Couplings in a Spin-1 Spin-Glass Model


  A spin-1 model, appropriated to study the competition between bilinear
(J_{ij}S_{i}S_{j}) and biquadratic (K_{ij}S_{i}^{2}S_{j}^{2}) random
interactions, both of them with zero mean, is investigated. The interactions
are infinite-ranged and the replica method is employed. Within the
replica-symmetric assumption, the system presents two phases, namely,
paramagnetic and spin-glass, separated by a continuous transition line. The
stability analysis of the replica-symmetric solution yields, besides the usual
instability associated with the spin-glass ordering, a new phase due to the
random biquadratic couplings between the spins.

</DOC>
<DOC>
<DOCNO> 169599 </DOCNO>
Efficient factorization with a single pure qubit and $log N$ mixed


  It is commonly assumed that Shor's quantum algorithm for the efficient
factorization of a large number $N$ requires a pure initial state. Here we
demonstrate that a single pure qubit together with a collection of $log_2 N$
qubits in an arbitrary mixed state is sufficient to implement Shor's
factorization algorithm efficiently.

</DOC>
<DOC>
<DOCNO> 8709 </DOCNO>
Magnetotransport in an array of magnetic antidots


  Classical transport properties of an electron, moving in plain, in an array
of magnetic antidot has been calculated. The homogeneous magnetic field in
z-direction fills the whole space except of cylinders of radius r_0. The
magnetoresistance shows additional peak and minimum according to pinned orbits
at antidots and to propagating orbits in transport direction, respectively.

</DOC>
<DOC>
<DOCNO> 13336 </DOCNO>
Coherent coupling of two quantum dots embedded in an Aharonov-Bohm ring


  We define two laterally gated small quantum dots (~ 15 electrons) in an
Aharonov-Bohm geometry in which the coupling between the two dots can be
broadly changed. For weakly coupled quantum dots we find Aharonov-Bohm
oscillations. In an intermediate coupling regime we concentrate on the
molecular states of the double dot and extract the magnetic field dependence of
the coherent coupling.

</DOC>
<DOC>
<DOCNO> 170711 </DOCNO>
Non-perturbative solution of nonlinear Heisenberg equations


  A new non-perturbative method of solution of the nonlinear Heisenberg
equations in the finite-dimensional subspace is illustrated. The method, being
a counterpart of the traditional Schrodinger picture method, is based on a
finite operator expansion into the elementary processes. It provides us with
the insight into the nonlinear quantal interaction from the different point of
view. Thus one can investigate the nonlinear system in both pictures of quantum
mechanics.

</DOC>
<DOC>
<DOCNO> 119443 </DOCNO>
ISO observations of a sample of 60 micron peaker galaxies


  The sample of IRAS galaxies with spectral energy distributions that peak near
60 microns are called Sixty Micron Peakers (SMPs or 60PKs). Their generally
peculiar and amorphous morphologies, hot dust and lack of a cirrus component
have been interpreted as being indicative of a recent interaction/merger event.
Mid-infrared spectra of eight SMPs, obtained with ISOPHOT-S in the ~2-11 micron
band are presented. Four of the observed sources are H II region-like (H2)
galaxies, three are Seyfert 2 and one is unclassified. Emission attributed to
Polycyclic Aromatic Hydrocarbons (PAHs) at 6.2, 7.7 and 8.6 micron is
ubiquitous in the spectra. The PHOT-S spectrum of the H2 galaxy IRAS 23446+1519
exhibits a bright 11.04 micron line and an 8.6 micron feature of comparable
size to its 7.7 micron feature. [S IV] emission at 10.5 micron was detected in
three of four H2 galaxies and in one Seyfert 2 galaxy. The ratio of the 7.7
\textmu m PAH feature to the continuum at 7.7 micron (PAH L/C) divides the
eight SMPs at a ratio greater than 0.8 for H2 and less than 0.8 for Seyfert
galaxies. An anti-correlation between PAH L/C and the ratio of the continuum
flux at 5.9 micron to the flux at 60 micron is found, similar to that found in
ultraluminous infrared galaxies. Silicate absorption at approximately 9.7
micron was observed in the Seyfert 2 galaxy, IRAS 04385-0828 and in IRAS
03344-2103. The previously unclassified SMP galaxy IRAS 03344-2103 is probably
a Seyfert 2.

</DOC>
<DOC>
<DOCNO> 152583 </DOCNO>
Multi-Domain Walls in Massive Supersymmetric Sigma-Models


  Massive maximally-supersymmetric sigma models are shown to exhibit multiple
static kink-domain wall solutions that preserve 1/2 of the supersymmetry. The
kink moduli space admits a natural Kahler metric. We examine in some detail the
case when the target of the sigma model is given by the co-tangent bundle of
CP^n equipped with the Calabi metric, and we show that there exist BPS
solutions corresponding to n kinks at arbitrary separation. We also describe
how 1/4-BPS charged and intersecting domain walls are described in the
low-energy dynamics on the kink moduli space. We comment on the similarity of
these results to monopole dynamics.

</DOC>
<DOC>
<DOCNO> 178952 </DOCNO>
QGP fireball explosion


  We identify the major physics milestones in the development of strange
hadrons as an observable for both the formation of quark-gluon plasma, and of
the ensuing explosive disintegration of deconfined matter fireball formed in
relativistic heavy ion collisions at 160--20A GeV. We describe the physical
properties of QGP phase and show agreement with the expectations based on an
analysis of hadron abundances. We than also demonstrate that the m_t shape of
hadron spectra is in qualitative agreement with the sudden breakup of a
supercooled QGP fireball.

</DOC>
<DOC>
<DOCNO> 12116 </DOCNO>
High-pressure study of the non-Fermi liquid material U_2Pt_2In


  The effect of hydrostatic pressure (p<= 1.8 GPa) on the non-Fermi liquid
state of U_2Pt_2In is investigated by electrical resistivity measurements in
the temperature interval 0.3-300 K. The experiments were carried out on
single-crystals with the current along (I||c) and perpendicular (I||a) to the
tetragonal axis. The pressure effect is strongly current-direction dependent.
For I||a we observe a rapid recovery of the Fermi-liquid T^2-term with
pressure. The low-temperature resistivity can be analysed satisfactorily within
the magnetotransport theory of Rosch, which provides strong evidence for the
location of U_2Pt_2In at an antiferromagnetic quantum critical point. For I||c
the resistivity increases under pressure, indicating the enhancement of an
additional scattering mechanism. In addition, we have measured the pressure
dependence of the antiferromagnetic ordering temperature (T_N= 37.6 K) of the
related compound U_2Pd_2In. A simple Doniach-type diagram for U_2Pt_2In and
U_2Pd_2In under pressure is presented.

</DOC>
<DOC>
<DOCNO> 123184 </DOCNO>
Nonthermal X-ray emission from young Supernova Remnants


  The cosmic-ray spectrum up to the knee ($E\sim 10^{15}$ eV) is attributed to
acceleration processes taking place at the blastwaves which bound supernova
remnants. Theoretical predictions give a similar estimate for the maximum
energy which can be reached at supernova remnant shocks by particle
acceleration. Electrons with energies of the order $\sim 10^{15}$ eV should
give a nonthermal X-ray component in young supernova remnants. Recent
observations of SN1006 and G347.3-0.5 confirm this prediction. We present a
method which uses hydrodynamical simulations to describe the evolution of a
young remnant. These results are combined with an algorithm which
simultaneously calculates the associated particle acceleration. We use the test
particle approximation, which means that the back-reaction on the dynamics of
the remnant by the energetic particles is neglected. We present synchrotron
maps in the X-ray domain, and present spectra of the energies of the electrons
in the supernova remnant. Some of our results can be compared directly with
earlier semi-analytical work on this subject by Reynolds [1].

</DOC>
<DOC>
<DOCNO> 152223 </DOCNO>
Supersymmetry and F-theory realization of the deformed conifold with


  It is shown that the deformed conifold solution with three-form flux, found
by Klebanov and Strassler, is supersymmetric, and that it admits a simple
F-theory description in terms of a direct product of the deformed conifold and
a torus. Some general remarks on Ramond-Ramond backgrounds and warped
compactifications are included.

</DOC>
<DOC>
<DOCNO> 11846 </DOCNO>
Integrable sigma models with theta=pi


  A fundamental result relevant to spin chains and two-dimensional disordered
systems is that the sphere sigma model with instanton coupling theta=pi has a
non-trivial low-energy fixed point and a gapless spectrum. This result is
extended to two series of sigma models with theta=pi: the SU(N)/SO(N) sigma
models flow to the SU(N)_1 WZW theory, while the O(2N)/O(N)\times O(N) models
flow to O(2N)_1 (2N free Majorana fermions). These models are integrable, and
the exact quasiparticle spectra and S matrices are found. One interesting
feature is that charges fractionalize when theta=pi. I compute the energy in a
background field, and verify that the perturbative expansions for \theta=0 and
pi are the same as they must be. I discuss the flows between the two sequences
of models, and also argue that the analogous sigma models with Sp(2N) symmetry,
the Sp(2N)/U(N) models, flow to Sp(2N)_1.

</DOC>
<DOC>
<DOCNO> 178480 </DOCNO>
Effect of Cluster Formation on Isospin Asymmetry in the Liquid-Gas Phase


  Nuclear matter within the liquid-gas phase transition region is investigated
in a mean-field two-component Fermi-gas model. Following largely analytic
considerations, it is shown that: (1) Due to density dependence of asymmetry
energy, some of the neutron excess from the high-density phase could be
expelled into the low-density region. (2) Formation of clusters in the gas
phase tends to counteract this trend, making the gas phase more liquid-like and
reducing the asymmetry in the gas phase. Flow of asymmetry between the
spectator and midrapidity region in reactions is discussed and a possible
inversion of the flow direction is indicated.

</DOC>
<DOC>
<DOCNO> 40216 </DOCNO>
Hadronic B Decays To Charm From CLEO


  Recent results include the measurement of B->D(*)pi+pi-pi-pi0 decays, with
rates of ~1.8% observation of a significant omega pi^- substructure that
appears to result from the decay of the rho' resonance, whose mass and width we
determine as 1418 MeV and 382 MeV, respectively. Using B to charmonium decays
we find that the neutral B fraction in Y(4S) decays is nearly half, that the CP
asymmetries in J/\psi K^(-/+) and psi' K^(-/+) are small, and we also report on
the first observation of B->eta_c K.

</DOC>
<DOC>
<DOCNO> 69229 </DOCNO>
Neutralino dark matter vs galaxy formation


  Neutralino dark matter may be incompatible with current cold dark matter
models with cuspy dark halos, because excessive synchrotron radiation may
originate from neutralino annihilations close to the black hole at the galactic
center.

</DOC>
<DOC>
<DOCNO> 67825 </DOCNO>
How Could the Proton Transversity be Measured


  The perspectives of two new nonstandard methods of transversal quark
polarization measurement are considered: the jet handedness and the so-called
"Collins effect" due to spin dependent T-odd fragmentation function responsible
for the left-right asymmetry in fragmenting of transversally polarized quarks.
Recent experimental indications in favor of these effects are observed: 1.The
correlation of the T-odd one-particle fragmentation functions found by DELPHI
in $Z\to 2$-jet decay. Integrated over the fraction of longitudinal and
transversal momenta, this correlation is of 1.6% order, which means order of
13% for the analyzing power. 2.A rather large ($\approx10%$) handedness
transversal to the production plane observed in the diffractive production of
($\pi^-\pi^+\pi^-$) triples from nuclei by the $40 {\rm GeV/c}$ $\pi^-$--beam.
It shows a clear dynamic origin and resembles the single spin asymmetry
behavior.
  All this makes us hope to use these effects in polarized DIS experiments for
transversity measurement. The first estimation of transversity was done by
using the azimuthal asymmetry in semi-inclusive DIS recently measured by HERMES
and SMC.

</DOC>
<DOC>
<DOCNO> 100211 </DOCNO>
On Numerically Effective Log Canonical Divisors


  Let $(X,\Delta)$ be a 4-dimensional log variety which is proper over the
field of complex numbers and with only divisorial log terminal singularities.
The log canonical divisor $K_X+\Delta$ is semi-ample, if it is nef (numerically
effective) and the Iitaka dimension $\kappa(X,K_X+\Delta)$ is strictly
positive. For the proof, we use Fujino's abundance theorem for semi log
canonical threefolds.

</DOC>
<DOC>
<DOCNO> 71497 </DOCNO>
QCD at finite isospin density: from pion to quark-antiquark condensation


  QCD at finite isospin chemical potential mu_I is studied. This theory has no
fermion sign problem and can be simulated on the lattice using present-day
techniques. We solve this theory analytically in two limits: low mu_I where
chiral perturbation theory is applicable, and asymptotically high mu_I where
perturbative QCD is at work. At low isospin density the ground state is a
superfluid pion condensate. At very high density it is a Fermi liquid with
Cooper pairing. The pairs carry the same quantum numbers as the pions.
Motivated by this observation, we put forward a conjecture that the transition
from hadron to quark matter is smooth. The conjecture passes several nontrivial
tests. Our results imply a nontrivial phase diagram in the space of temperature
and chemical potentials of isospin and baryon number. At asymtotically large
values of mu_I and small values of baryon chemical potential the ground state
is in a phase similar to Fulde-Ferrell-Larkin-Ovchinnikov phase. It is
characterized by a spatially modulated superfluid order parameter
<ubar*gamma_5*d> and may be the asymptotic limit of the inhomogeneous pion
condensation phase advocated by Migdal and others.

</DOC>
<DOC>
<DOCNO> 151749 </DOCNO>
Harmonic-Superspace Transform For N=3 SYM-Equations


  The SU(3)/U(1) x U(1) harmonic variables are used in the harmonic-superspace
representation of the D=4, N=3 SYM-equations. The harmonic superfield equations
of motion in the simple non-covariant gauge contain the nilpotent harmonic
analytic connections. It is shown that these harmonic SYM-equations are
equivalent to the finite set of solvable linear iterative equations.

</DOC>
<DOC>
<DOCNO> 69921 </DOCNO>
Cosmological magnetic fields


  Magnetic fields are observed not only in stars, but in galaxies, clusters,
and even high redshift Lyman-alpha systems. In principle, these fields could
play an important role in structure formation and also affect the anisotropies
in the cosmic microwave background radiation (CMB). The study of cosmological
magnetic fields aims not only to quantify these effects on large-scale
structure and the CMB, but also to answer one of the outstanding puzzles of
modern cosmology: when and how do magnetic fields originate? They are either
primordial, i.e. created before the onset of structure formation, or they are
generated during the process of structure formation itself.

</DOC>
<DOC>
<DOCNO> 174529 </DOCNO>
An Excitation Function of K$^-$ and K$^+$ Production in Au+Au Reactions


  Mid-rapidity spectra and yields of K$^-$ and K$^+$ have been measured for
Au+Au collisions at 4, 6, 8, and 10.7 AGeV. The K$^-$ yield increases faster
with beam energy than for K$^+$ and hence the K$^-$/K$^+$ ratio increases with
beam energy. This ratio is studied as a function of both $\sqrt{s}$ and
$\sqrt{s}$-$\sqrt{s_{th}}$ which allows the direct comparison of the kaon
yields with respect to the production threshold in p+p reactions. For equal
$\sqrt{s}$ - $\sqrt{s_{th}}$ the measured ratio K$^-$/K$^+$=0.2 at energies
above threshold in contrast to the K$^-$/K$^+$ ratio of near unity observed at
energies below threshold. The use of the K$^-$/K$^+$ ratio to test the
predicted changes of kaon properties in dense nuclear matter is discussed.

</DOC>
<DOC>
<DOCNO> 100771 </DOCNO>
Epsilon constants and Arakelov Euler characteristics


  We conjecture that the logarithm of the absolute value of the constant in the
functional equation of the Hasse-Weil L-function of a variety X over Z is equal
to a certain Arakelov de Rham Euler characteristic of X. This generalizes the
fact that the constant in the functional equation of the zeta function of a
number field is the square root of the discriminant of its ring of integers. We
show that this conjecture is equivalent to Bloch's conjecture which expresses
the conductor as the degree of a localized Chern class of the differentials. We
prove both of these conjectures in the case of "tame" reduction.

</DOC>
<DOC>
<DOCNO> 84228 </DOCNO>
Background Estimation in a Gravitational Wave Experiment


  The problem to estimate the background due to accidental coincidences in the
search for coincidences in gravitational wave experiments is discussed. The use
of delayed coincidences obtained by orderly shifting the event times of one of
the two detectors is shown to be the most correct

</DOC>
<DOC>
<DOCNO> 150626 </DOCNO>
On Type II NS5-branes in the presence of an RR field


  In this letter we use Type II NS5-branes in the presence of an RR field at
the decoupling limit to study a non-commutative version of little string
theory. We shall see that the decoupling limit of NS5-branes in the presence of
an RR field is completely different from the one we had in ordinary little
string theory; in particular for Type IIA NS5-branes this decoupling limit can
be defined only when the theory is wrapped on a circle, but nevertheless flows
to the ordinary non-compact (0,2) theory at the IR limit. We also see that
these theories, in the UV regime, where the non-commutative effects are
important, can be described by smeared ordinary D3(D2)-branes in Type IIB(A)
string theory.

</DOC>
<DOC>
<DOCNO> 68627 </DOCNO>
Anomalous U(1) Symmetry and Sparticles


  Using anomalous U(1) symmetry the quark mass texture is determined uniquely.
We analyze squark mass spectrum based on the above mass matrices and discuss
the possibility to solve the problems of FCNC and CP caused by complex phases
of soft terms, including the viewpoint of M theory.

</DOC>
<DOC>
<DOCNO> 152599 </DOCNO>
Nonrenormalization theorems for N=2 Super Yang-Mills


  The BRST algebraic proofs of the the nonrenormalization theorems for the beta
functions of N=2 and N=4 Super Yang-Mills theories are reviewed.

</DOC>
<DOC>
<DOCNO> 117241 </DOCNO>
Benchmark {\em ab initio} energy profiles for the gas-phase S$_N$2


  The energetics of the gas-phase S$_N$2 reactions Y$^-$ + CH$_3$X
$\longrightarrow$ CH$_3$Y + X$^-$ (where X,Y = F, Cl, Br), were studied using
(variants on) the recent W1 and W2 {\em ab initio} computational
thermochemistry methods. Our computed benchmark data (including cases for which
experimental data are unavailable altogether) are used to assess the quality of
a number of semiempirical compound thermochemistry schemes such as G2 theory,
G3 theory, and CBS-QB3, as well as a variety of density functional theory
methods. Upon applying some modifications to the level of theory used for the
reference geometry (adding diffuse functions, replacing B3LYP by the very
recently proposed mPW1K functional), the compound methods appear to perform
well. Only the 'half-and-half' functionals BH&HLYP and mPWH&HPW91, and the
empirical mPW1K functional, consistently find all required stationary points;
the other functionals fail to find a transition state in the F/Br case. BH&HLYP
and mPWH&HPW91 somewhat overcorrect for the tendency of B3LYP (and, to a lesser
extent, mPW1PW91) to underestimate barrier heights. The Becke97 and Becke97-1
functionals perform similarly to B3LYP for the problem under study, while the
HCTH and HCTH-120 functionals both appear to underestimate central barriers.
HCTH underestimates complexation energies; this problem is resolved in
HCTH-120. mPW1K appears to exhibit the best performance of the functionals
considered, although its energetics are still inferior to the compound
thermochemistry methods.

</DOC>
<DOC>
<DOCNO> 9238 </DOCNO>
Large sample-to-sample fluctuations of the nonequilibrium critical


  We present a theory for the nonequilibrium current in a mesoscopic Josephson
junction which is coupled to a normal electron reservoir, and apply it to a
chaotic junction. Large sample-to-sample fluctuations of the critical current
$I_{\rm c}$ are found, with ${rms} I_{\rm c} \simeq \sqrt{N}e\Delta/\hbar$,
when the voltage difference eV between the electron reservoir and the junction
exceeds the superconducting gap $\Delta$ and the number of modes N connecting
the junction to the superconducting electrodes is large.

</DOC>
<DOC>
<DOCNO> 169942 </DOCNO>
Mathematical Foundations of Holonomic Quantum Computer


  We make a brief review of (optical) Holonomic Quantum Computer (or
Computation) proposed by Zanardi and Rasetti (quant-ph/9904011) and Pachos and
Chountasis (quant-ph/9912093), and give a mathematical reinforcement to their
works.

</DOC>
<DOC>
<DOCNO> 70354 </DOCNO>
Magnetic monopoles and vortices in the standard model of electroweak


  These lectures start with an elementary introduction to the subject of
magnetic monopoles which should be accesible from any physics background. In
the Weinberg-Salam model of electroweak interactions, magnetic monopoles appear
at the ends of a type of non-topological vortices called electroweak strings.
These will also be discussed, as well as recent simulations of their formation
during a phase transition which indicate that, in the (unphysical) range of
parameters in which the strings are classically stable, they can form with a
density comparable to topological vortices.

</DOC>
<DOC>
<DOCNO> 101038 </DOCNO>
Clifford Homomorphisms and Higher Spin Dirac Operators


  We present a generalization of the Clifford action for other representations
spaces of $Spin(n)$, which is called the Clifford homomorphism. Their
properties extend to the ones for the higher spin Dirac operators on spin
manifolds. In particular, we have general Bochner identities for them, and an
eigenvalue estimate of a Laplace type operator on any associated bundle.

</DOC>
<DOC>
<DOCNO> 150322 </DOCNO>
Bi-local Fields in Noncommutative Field Theory


  We propose a bi-local representation in noncommutative field theory. It
provides a simple description for high momentum degrees of freedom. It also
shows that the low momentum modes can be well approximated by ordinary local
fields. Long range interactions are generated in the effective action for the
lower momentum modes after integrating out the high momentum bi-local fields.
The low momentum modes can be represented by diagonal blocks in the matrix
model picture and the high momentum bi-local fields correspond to off-diagonal
blocks. This block-block interaction picture simply reproduces the infrared
singular behaviors of nonplanar diagrams in noncommutative field theory.

</DOC>
<DOC>
<DOCNO> 150801 </DOCNO>
Target Space Duality II: Applications


  We apply the framework developed in Target Space Duality I: General Theory.
We show that both nonabelian duality and Poisson-Lie duality are examples of
the general theory. We propose how the formalism leads to a systematic study of
duality by studying few scenarios that lead to open questions in the theory of
Lie algebras. We present evidence that there are probably new examples of
irreducible target space duality.

</DOC>
<DOC>
<DOCNO> 13475 </DOCNO>
An efficient, multiple range random walk algorithm to calculate the


  We present a new Monte Carlo algorithm that produces results of high accuracy
with reduced simulational effort. Independent random walks are performed
(concurrently or serially) in different, restricted ranges of energy, and the
resultant density of states is modified continuously to produce locally flat
histograms. This method permits us to directly access the free energy and
entropy, is independent of temperature, and is efficient for the study of both
1st order and 2nd order phase transitions. It should also be useful for the
study of complex systems with a rough energy landscape.

</DOC>
<DOC>
<DOCNO> 68268 </DOCNO>
Static Solutions for Brane Models with a Bulk Scalar Field


  We present static solutions of the 5-dimensional Einstein equations in the
brane-world scenario by using two different approaches for the stabilization of
the extra dimension. Assuming a ``phenomenological'' stabilization mechanism,
that creates a non-vanishing $\hat T^5_5$ in the bulk, we construct a two-brane
model, which allows both branes to have positive self-energies. We then
consider a candidate theory for the dynamical stabilization, through the
introduction of a massless scalar field in the bulk, which interacts with the
branes. We find exact static solutions for the metric and scalar field in the
bulk and demonstrate that the inter-brane distance is determined by the
parameters of scalar field-brane interactions. However, these solutions are
always accompanied by a correlation between the bulk cosmological constant, the
brane self-energies and the interaction terms of the scalar field with the
branes and thus cannot be considered as candidates for the phenomenologically
viable stabilized geometry. We find that the aforementioned correlation cannot
be avoided even in the case of a single-brane solution with positive
self-energy where the fifth dimension ends on a singularity.

</DOC>
<DOC>
<DOCNO> 120117 </DOCNO>
Observational Properties of Diffuse Halos in Clusters


  The number of known diffuse radio sources in clusters of galaxies has grown
in recent years, making it possible to derive statistical properties of these
sources and of the hosting clusters. We show that diffuse sources are
associated with X-ray luminous clusters which have undergone recent merger
processes. The radio and X-ray structures are often similar, and correlations
are found between radio and X-ray parameters. This is indication of a link
between the diffuse relativistic and thermal plasma in clusters of galaxies.

</DOC>
<DOC>
<DOCNO> 122825 </DOCNO>
Morphological Evolution of Galaxies to z=4


  Galaxies have clearly evolved since the universe was 1 Gyr old, but methods
to trace and quantify this evolution are still in their infancy. In this paper
I demonstrate that with the careful use of a `physical morphology' it is
possible to determine quantitatively how the process of galaxy evolution is
occurring out to z=4. Using a system of parameters that traces star formation
and galaxy interactions, I show how distinct galaxy populations at high-z can
be identified in deep high-resolution optical and NIR images. These tools are
also used to measure a potential merger fraction of galaxies from 0<z<4. If
these methods are reliable, as is suggested by a local galaxy calibration, the
merger fraction of galaxies scales as (1+z)^{2.1+/-0.5}, peaks near z=2, and
declines thereafter. I also discuss how this system is likely part of the
ultimate physical classification of galaxies.

</DOC>
<DOC>
<DOCNO> 13252 </DOCNO>
Exact Potts Model Partition Functions on Wider Arbitrary-Length Strips


  We present exact calculations of the partition function of the q-state Potts
model for general q and temperature on strips of the square lattice of width
L_y=3 vertices and arbitrary length L_x with periodic longitudinal boundary
conditions, of the following types: (i) (FBC_y,PBC_x)= cyclic, (ii)
(FBC_y,TPBC_x)= M\"obius, (iii) (PBC_y,PBC_x)= toroidal, and (iv)
(PBC_y,TPBC_x)= Klein bottle, where FBC and (T)PBC refer to free and (twisted)
periodic boundary conditions. Results for the L_y=2 torus and Klein bottle
strips are also included. In the infinite-length limit the thermodynamic
properties are discussed and some general results are given for low-temperature
behavior on strips of arbitrarily great width. We determine the submanifold in
the {\mathbb C}^2 space of q and temperature where the free energy is singular
for these strips. Our calculations are also used to compute certain quantities
of graph-theoretic interest.

</DOC>
<DOC>
<DOCNO> 11005 </DOCNO>
Nonequilibrium molecular dynamics simulation of rapid directional


  We present the results of non-equilibrium molecular dynamics simulations for
the growth of a solid binary alloy from its liquid phase. The regime of high
pulling velocities, $V$, for which there is a progressive transition from
solute segregation to solute trapping, is considered. In the segregation
regime, we recover the exponential form of the concentration profile within the
liquid phase. Solute trapping is shown to settle in progressively as $V$ is
increased and our results are in good agreement with the theoretical
predictions of Aziz [J. Appl. Phys. {\bf 53}, 1158 (1981)]. In addition, the
fluid advection velocity is shown to remain directly proportional to $V$, even
at the highest velocities considered here ($V\simeq10$ms$^{-1}$).

</DOC>
<DOC>
<DOCNO> 150851 </DOCNO>
Q-ball Dynamics


  We investigate the dynamics of Q-balls in one, two and three space
dimensions, using numerical simulations of the full nonlinear equations of
motion. We find that the dynamics of Q-balls is extremely complex, involving
processes such as charge transfer and Q-ball fission. We present results of
simulations which illustrate the salient features of 2-Q-ball interactions and
give qualitative arguments to explain them in terms of the evolution of the
time-dependent phases.

</DOC>
<DOC>
<DOCNO> 80839 </DOCNO>
Vortices in SU(2) lattice gauge theory


  We investigate some properties of thick vortices and thick monopoles in the
SU(2) lattice gauge theory by inserting operators that create these
excitations. We measure the derivative of the free energy of the vortex with
respect to the coupling and we find that it falls exponentially with the cross
sectional area of the vortex. We also study the monopole-monopole potential
energy of thick and thin monopoles. Our results suggest that vortices and
monopoles of increasing thickness will play an important role in the large
$\beta$ limit.

</DOC>
<DOC>
<DOCNO> 84548 </DOCNO>
The Consistent Newtonian Limit of Einstein's Gravity with a Cosmological


  We derive the `exact' Newtonian limit of general relativity with a positive
cosmological constant $\Lambda$. We point out that in contrast to the case with
$\Lambda = 0 $, the presence of a positive $\Lambda$ in Einsteins's equations
enforces, via the condition $| \Phi | \ll 1$, on the potential $\Phi$, a range
${\cal R}_{max}(\Lambda) \gg r \gg {\cal R}_{min} (\Lambda)$, within which the
Newtonian limit is valid. It also leads to the existence of a maximum mass,
${\cal M}_{max}(\Lambda)$. As a consequence we cannot put the boundary
condition for the solution of the Poisson equation at infinity. A boundary
condition suitably chosen now at a finite range will then get reflected in the
solution of $\Phi$ provided the mass distribution is not spherically symmetric.

</DOC>
<DOC>
<DOCNO> 70339 </DOCNO>
Lepton Flavour Violation In Supersymmetric Models with Trilinear


  Supersymmetry with R-parity violation (RPV) provides an interesting framework
for naturally accommodating small neutrino masses. Within this framework, we
discuss the lepton-flavour violating (LFV) processes mu -> e gamma, mu -> eee,
and mu -> e conversion in nuclei. We make a detailed study of the observables
related to LFV in different RPV models, and compare them to the expectations of
R-conserving supersymmetry with heavy right-handed neutrinos. We show that the
predictions are vastly different and uniquely characterise each model, thus
providing a powerful framework for experimentally distinguishing between
different theories of LFV. Besides the obvious possibility of amplified
tree-level generation of mu -> eee and mu -> e conversion in nuclei, we find
that even in the case where these processes arise at the one-loop level, their
rates are comparable to that of mu -> e gamma, in clear contrast to the
predictions of R-conserving models. We conclude that in order to distinguish
between the different models, such a combined study of all the LFV processes is
necessary, and that measuring P-odd asymmetries in polarised mu -> eee can play
a decisive role. We also comment on the intriguing possibility of RPV models
yielding a large T-odd asymmetry in the decay of polarised mu -> eee.

</DOC>
<DOC>
<DOCNO> 8371 </DOCNO>
L\'evy Distribution of Single Molecule Line Shape Cumulants in Low


  We investigate the distribution of single molecule line shape cumulants,
$\kappa_1,\kappa_2,...$, in low temperature glasses based on the sudden jump,
standard tunneling model. We find that the cumulants are described by L\'evy
stable laws, thus generalized central limit theorem is applicable for this
problem.

</DOC>
<DOC>
<DOCNO> 9541 </DOCNO>
Effective charges and statistical signatures in the noise of normal


  Shot noise is studied in a single normal metal-superconductor (N-S) junction
at finite frequency, and for branched N-S junctions at zero frequency. The
noise spectral density displays a singularity at the Josephson frequency
($\omega = 2eV/\hbar$) when the applied bias is smaller than gap of the
superconductor. Yet, in the limit $eV\gg \Delta$, quasiparticle contributions
yield a singularity at $\omega = eV/\hbar$ analogous to that of a normal metal.
The crossover between these two regimes shows new structures in the noise
characteristic, pointing out the failure of the effective charge model. As an
alternative to a finite frequency measurement, if a sinusoidal external field
is superposed to the constant bias (non stationary Aharonov--Bohm effect), the
second derivative of the zero frequency noise with respect to the voltage
exhibits peaks when the frequency of the perturbation is commensurate with the
Josephson frequency. Finally, the statistical aspects of noise are studied with
an analog of the Hanbury-Brown and Twiss experiment for fermions: a
superconductor connected to two normal leads. Noise correlations are found to
be either negative (fermionic) or positive (bosonic), due to the presence of
evanescent Cooper pairs in the normal side of the junction, in the latter case.

</DOC>
<DOC>
<DOCNO> 123214 </DOCNO>
Evidence for solar-like oscillations in beta Hydri


  We have made a clear detection of excess power, providing strong evidence for
solar-like oscillations in the G2 subgiant beta Hyi. We observed this star over
five nights with the UCLES echelle spectrograph on the 3.9-m Anglo-Australian
Telescope, using an iodine absorption cell as a velocity reference. The time
series of 1196 velocity measurements shows an rms scatter of 3.30 m/s, and the
mean noise level in the amplitude spectrum at frequencies above 0.5 mHz is 0.11
m/s. We see a clear excess of power centred at 1.0 mHz, with peak amplitudes of
about 0.5 m/s, in agreement with expectations for this star. Fitting the
asymptotic relation to the power spectrum indicates the most likely value for
the large separation is 56.2 microHz, also in good agreement with the known
properties of beta Hyi.

</DOC>
<DOC>
<DOCNO> 116783 </DOCNO>
A Superconductive, Low Beta Single Gap Cavity for a High Intensity


  A single gap, 352 MHz superconducting reentrant cavity for 5-100 MeV beams
has been designed and it is presently under construction. This development is
being done in the framework of a 30 mA proton linac project for nuclear waste
transmutation. Mechanical, cryogenic and rf design characteristics of such
cavities will be described.

</DOC>
<DOC>
<DOCNO> 100739 </DOCNO>
Determinants of Hankel Matrices


  The purpose of this paper is to compute asymptotically Hankel determinants
for weights that are supported in a semi-infinite interval.The main idea is to
reduce the problem to determinants of other operators whose determinant
asymptotics are well known.

</DOC>
<DOC>
<DOCNO> 12322 </DOCNO>
The Thermodynamics of Social Processes: The Teen Birth Phenomenon


  We argue that a process of social interest is a balance of order and
randomness, thereby producing a departure from a stationary diffusion process.
The strength of this effect vanishes if the order to randomness intensity ratio
vanishes, and this property allows us to reveal, although in an indirect way,
the existence of a finite order to randomness intensity ratio. We aim at
detecting this effect. We introduce a method of statistical analysis
alternative to the compression procedures, with which the limitations of the
traditional Kolmogorov-Sinai approach are bypassed. We prove that this method
makes it possible for us to build up a memory detector, which signals the
presence of even very weak memory, provided that this is persistent over large
time intervals. We apply the analysis to the study of the teen birth phenomenon
and we find that the unmarried teen births are a manifestation of a social
process with a memory more intense than that of the married teens. We attempt
to give a social interpretation of this effect.

</DOC>
<DOC>
<DOCNO> 123309 </DOCNO>
Circumstellar Nebulae in Young Supernova Remnants


  Supernovae descendent from massive stars explode in media that have been
modified by their progenitors' mass loss and UV radiation. The supernova ejecta
will first interact with the circumstellar material shed by the progenitors at
late evolutionary stages, and then interact with the interstellar material.
Circumstellar nebulae in supernova remnants can be diagnosed by their small
expansion velocities and high [N II]/H$\alpha$ ratios. The presence of
circumstellar nebulae appears ubiquitous among known young supernova remnants.
These nebulae can be compared to those around evolved massive stars to assess
the nature of their supernova progenitors. Three types of archeological
artifacts of supernova progenitors have been observed in supernovae and/or
young supernova remnants: (1) deathbed ejecta, (2) circumstellar nebulae, and
(3) interstellar bubbles. Examples of these three types are given.

</DOC>
<DOC>
<DOCNO> 84120 </DOCNO>
Some Recent Progress in Classical General Relativity


  In this short survey paper, we discuss certain recent results in classical
gravity. Our main attention is restricted to two topics: the positive mass
conjecture and its extensions to the case with horizons, including the Penrose
conjecture (Part I), and the interaction of gravity with other force fields and
quantum-mechanical particles (Part II).

</DOC>
<DOC>
<DOCNO> 9353 </DOCNO>
Magnetoresistance and electronic structure of asymmetric GaAs/AlGaAs


  Bilayer two-dimensional electron systems formed by a thin barrier in the GaAs
buffer of a standard heterostructure were investigated by magnetotransport
measurements. In magnetic fields oriented parallel to the electron layers, the
magnetoresistance exhibits an oscillation associated with the depopulation of
the higher occupied subband and the field-induced transition into a decoupled
bilayer. Shubnikov-de Haas oscillations in slightly tilted magnetic fields
allow to reconstruct the evolution of the electron concentration in the
individual subbands as a function of the in-plane magnetic field. The
characteristics of the system derived experimentally are in quantitative
agreement with numerical self-consistent-field calculations of the electronic
structure.

</DOC>
<DOC>
<DOCNO> 11693 </DOCNO>
Field theory of spin-singlet quantum Hall states


  We formulate a field theory for a class of spin-singlet quantum Hall states
(the Haldane-Rezayi state and its variants) which have been proposed for the
quantized Hall plateaus observed at the second lowest Landau level. A new
essential ingredient is a class of super Chern-Simons field. We show that the
known properties of the states are consistently described by it. We also give a
2+1 dimensional hierarchical construction. Implications of the proposal are
discussed and a new physical picture of composite particles at the second
lowest Landau level emerges.

</DOC>
<DOC>
<DOCNO> 71004 </DOCNO>
Rare decays $B\to X_sl^+l^-$ and $B\to K^{(*)}l^+l^-$ in SM and beyond


  After a brief review of the inclusive and exclusive rare semileptonic decays
of B mesons in the standard model (SM), an overview of recent theoretical
developments in this field is given. New physics effects on various observables
such as branching ratio, backward-forward asymmetry, polarization of lepton and
CP violation in the decays are anlyzed in models beyond SM (supersymmetric
models and two Higgs doublet models).

</DOC>
<DOC>
<DOCNO> 101909 </DOCNO>
On tensor categories attached to cells in affine Weyl groups


  We prove a conjecture by Lusztig, which describes the tensor categories of
perverse sheaves on affine flag manifolds, with tensor structure provided by
truncated convolution, in terms of the Langlands dual group. We also give a
geometric (categorical) description of Lusztig's bijection between two-sided
cells in an affine Weyl group, and unipotent conjugacy classes in the Langlands
dual group. The main tool is the sheaf-theoretic construction of the center of
the affine Hecke algebra due to Gaitsgory (based on ideas of Beilinson and
Kottwitz), see math.AG/9912074.

</DOC>
<DOC>
<DOCNO> 69695 </DOCNO>
Glueballs: A central mystery


  Glueball candidates and qqbar mesons have been found to be produced with
different momentum and angular dependences in the central region of pp
collisions. This talk illustrates this phenomenon and explains the phi and t
dependences of mesons with JPC = 0++,0-+, 1++, 2++ and 2-+. For production of
0++ and 2++ mesons the analysis reveals a systematic behaviour in the data that
appears to distinguish between qqbar and non-qqbar or glueball candidates. An
explanation is given for the absence of 0-+ glueball candidates in central
production at present energies and the opportunity for their discovery at RHIC
is noted.

</DOC>
<DOC>
<DOCNO> 122488 </DOCNO>
Two Types of Radio Galaxies: A New Approach


  We do not fully understand the dynamics and evolution of a radio galaxy.
Models of classical double (Type II) sources are in a reasonable state, but
these objects are rare. Non-type II sources (generically called Type I) are far
more common, but much less well understood. In this paper I use the data to
suggest possible new models for Type I sources, and discuss the physical
questions which these new models raise.

</DOC>
<DOC>
<DOCNO> 120451 </DOCNO>
A Possible X-ray and Radio Counterpart of the High-Energy Gamma-ray


  The identity of the persistent EGRET sources in the Galactic plane is largely
a mystery. For one of these, 3EG J2227+6122, our complete census of X-ray and
radio sources in its error circle reveals a remarkable superposition of an
incomplete radio shell with a flat radio spectrum, and a compact, power-law
X-ray source with photon index Gamma = 1.5 and with no obvious optical
counterpart. The radio shell is polarized at a level of 25%. The anomalous
properties of the radio source prevent us from deriving a completely
satisfactory theory as to its nature. Nevertheless, using data from ROSAT,
ASCA, the VLA, and optical imaging and spectroscopy, we argue that the X-ray
source may be a young pulsar with an associated wind-blown bubble or bow shock
nebula, and an example of the class of radio-quiet pulsars which are
hypothesized to comprise the majority of EGRET sources in the Galaxy. The
distance to this source can be estimated from its X-ray absorption as 3 kpc. At
this distance, the X-ray and gamma-ray luminosities would be 1.7x10^{33} and
3.7x10^{35} erg s^{-1}, respectively, which would require an energetic pulsar
to power them.
  If, on the contrary, this X-ray source is not the counterpart of 3EG
J2227+6122, then by process of elimination the X-ray luminosity of the latter
must be less than 10^{-4} of its gamma-ray luminosity, a condition not
satisfied by any established class of gamma-ray source counterpart. This would
require the existence of at least a quantitatively new type of EGRET source, as
has been suggested in studies of other EGRET fields.

</DOC>
<DOC>
<DOCNO> 83226 </DOCNO>
A One-Time Pad based Cipher for Data Protection in Distributed


  A one-time pad (OTP) based cipher to insure both data protection and
integrity when mobile code arrives to a remote host is presented. Data
protection is required when a mobile agent could retrieve confidential
information that would be encrypted in untrusted nodes of the network; in this
case, information management could not rely on carrying an encryption key. Data
integrity is a prerequisite because mobile code must be protected against
malicious hosts that, by counterfeiting or removing collected data, could cover
information to the server that has sent the agent. The algorithm described in
this article seems to be simple enough, so as to be easily implemented. This
scheme is based on a non-interactive protocol and allows a remote host to
change its own data on-the-fly and, at the same time, protecting information
against handling by other hosts.

</DOC>
<DOC>
<DOCNO> 13097 </DOCNO>
Quantized acoustoelectric current in a finite-length ballistic quantum


  Fluctuations in the acoustoelectric current, induced by a surface acoustic
wave propagating along a ballistic quantum channel, are considered. We focus on
the large wave-amplitude case, in which it has been experimentally found that
the current is quantized, and analyze the noise spectrum. A phenomenological
description of the process, in terms of a random pulse sequence, is proposed.
The important ingredients of this description are the probabilities, p_n, for a
surface acoustic wave well to capture n electrons. It is found that from the
noise characteristics one can obtain these probabilities, and also estimate the
typical length scales of the regions in which the electrons are trapped.

</DOC>
<DOC>
<DOCNO> 68739 </DOCNO>
Supersymmetry Breaking, Fermion Masses and a Small Extra Dimension


  We present a supersymmetric model in which the observed fermion masses and
mixings are generated by localizing the three generations of matter and the two
Higgs fields at different locations in a compact extra dimension. Supersymmetry
is broken by the shining method and the breaking is communicated to standard
model fields via gaugino mediation. Quark masses, CKM mixing angles and the mu
term are generated with all dimensionless couplings of O(1). All dimensionful
parameters are of order the five-dimensional Planck scale except for the size
of the extra dimension which is of order the GUT scale. The superpartner
spectrum is highly predictive and is found to have a neutralino LSP over a wide
range of parameter space. The resulting phenomenology and interesting
extensions of the model are briefly discussed.

</DOC>
<DOC>
<DOCNO> 121342 </DOCNO>
ARCS, The Arcminute Radio Cluster-lens Search - I. Selection Criteria


  We present the results of an unbiased radio search for gravitational lensing
events with image separations between 15 and 60 arcsec, which would be
associated with clusters of galaxies with masses >10^{13-14}M_{\sun}. A parent
population of 1023 extended radio sources stronger than 35 mJy with stellar
optical identifications was selected using the FIRST radio catalogue at 1.4 GHz
and the APM optical catalogue. The FIRST catalogue was then searched for
companions to the parent sources stronger than 7 mJy and with separation in the
range 15 to 60 arcsec. Higher resolution observations of the resulting 38 lens
candidates were made with the VLA at 1.4 GHz and 5 GHz, and with MERLIN at 5
GHz in order to test the lens hypothesis in each case. None of our targets was
found to be a gravitational lens system. These results provide the best current
constraint on the lensing rate for this angular scale, but improved
calculations of lensing rates from realistic simulations of the clustering of
matter on the relevant scales are required before cosmologically significant
constraints can be derived from this null result. We now have an efficient,
tested observational strategy with which it will be possible to make an
order-of-magnitude larger unbiased search in the near future.

</DOC>
<DOC>
<DOCNO> 101527 </DOCNO>
Hidden classical symmetry in quantum spaces at roots of unity : From


  We study relations between different kinds of non-commutative spheres which
have appeared in the context of ADS/CFT correspondences recently, emphasizing
the connections between spaces that have manifest quantum group symmetry and
spaces that have manifest classical symmetry. In particular we consider the
quotient $SU_q(2)/U(1)$ at roots of unity, and find its relations with the
fuzzy sphere with manifest classical SU(2) symmetry. Deformation maps between
classical and quantum symmetry, the $U_q(SU(2))$ module structure of quantum
spheres and the structure of indecomposable representations of $U_q(SU(2))$ at
roots of unity conspire in an interesting way to allow the relation between
manifestly $U_q(SU(2)$ symmetric spheres and manifestly U(SU(2)) symmetric
spheres. The relation suggests that a subset of field theory actions on the
q-sphere are equivalent to actions on the fuzzy sphere. The results here are
compatible with the proposal that quantum spheres at roots of unity appear as
effective geometries which account for finite N effects in the ADS/CFT
correspondence.

</DOC>
<DOC>
<DOCNO> 13562 </DOCNO>
Theory of strongly correlated f and d-electron systems. I. Exact


  The theory of correlated electron systems is formulated in a form which
allows to use as a reference point an ab initio band structure theory (AIBST).
The theory is constructed in two steps. As a first step the total Hamiltonian
is transformed into a correlated form. In order to elucidate the microscopical
origin of the parameters of the periodical Hubbard-Anderson model (PHAM) the
terms of the full Hamiltonian which have the operator structure of PHAM are
separated. It is found that the matrix element of mixing interaction includes
ion-configuration and number-of-particles dependent contributions from the
Coulomb interaction. In a second step the diagram technique (DT) is developed
by means of generalization of the Baym-Kadanoff method for correlated systems.

</DOC>
<DOC>
<DOCNO> 99604 </DOCNO>
Addendum: Level Spacings for Integrable Quantum Maps in Genus Zero


  In this addendum we strengthen the results of math-ph/0002010 in the case of
polynomial phases. We prove that Cesaro means of the pair correlation functions
of certain integrable quantum maps on the 2-sphere at level N tend almost
always to the Poisson (uniform limit). The quantum maps are exponentials of
Hamiltonians which have the form a p(I) + b I, where I is the action, where p
is a polynomial and where a,b are two real numbers. We prove that for any such
family and for almost all a,b, the pair correlation tends to Poisson on average
in N. The results involve Weyl estimates on exponential sums and new metric
results on continued fractions. They were motivated by a comparison of the
results of math-ph/0002010 with some independent results on pair correlation of
fractional parts of polynomials by Rudnick-Sarnak.

</DOC>
<DOC>
<DOCNO> 84350 </DOCNO>
Noether Charges, Brown-York Quasilocal Energy and Related Topics


  The Lagrangian proposed by York et al. and the covariant first order
Lagrangian for General Relativity are introduced to deal with the (vacuum)
gravitational field on a reference background. The two Lagrangians are compared
and we show that the first one can be obtained from the latter under suitable
hypotheses. The induced variational principles are also compared and discussed.
A conditioned correspondence among Noether conserved quantities, quasilocal
energy and the standard Hamiltonian obtained by 3+1 decomposition is also
established. As a result, it turns out that the covariant first order
Lagrangian is better suited whenever a reference background field has to be
taken into account, as it is commonly accepted when dealing with conserved
quantities in non-asymptotically flat spacetimes. As a further advantage of the
use of a covariant first order Lagrangian, we show that all the quantities
computed are manifestly covariant, as it is appropriate in General Relativity.

</DOC>
<DOC>
<DOCNO> 69335 </DOCNO>
Basis-independent analysis of the sneutrino sector in R-parity violating


  In R-parity-violating supersymmetric models (with a conserved baryon number),
there are no quantum numbers that distinguish the lepton-doublet and down-type
Higgs supermultiplets. As a result, the R-parity-violating parameters depend on
the basis choice for these superfields, although physical observables are
independent of the choice of basis. This paper presents a basis-independent
computation of the sneutrino/antisneutrino squared-mass splitting in terms of
basis-independent quantities. Techniques are developed for an arbitrary number
of sneutrino generations; specific results are provided for the one, two and
three generation cases.

</DOC>
<DOC>
<DOCNO> 120553 </DOCNO>
Statistical properties of visual binaries as tracers of the formation of


  In this review, we summarize the observed statistical properties of visual
binaries in various young stellar clusters. The binary frequency, orbital
period distribution and mass ratio distribution are considered for populations
of both low-mass and high-mass stars. These properties are then compared to
numerical models of the dynamical evolution of stellar clusters and to the
predictions of binary formation mechanisms.

</DOC>
<DOC>
<DOCNO> 118427 </DOCNO>
On the Structure of Advective Accretion Disks At High Luminosity


  Global solutions of optically thick advective accretion disks around black
holes are constructed. The solutions are obtained by solving numerically a set
of ordinary differential equations corresponding to a steady axisymmetric
geometrically thin disk. We pay special attention to consistently satisfy the
regularity conditions at singular points of the equations. For this reason we
analytically expand a solution at the singular point, and use coefficients of
the expansion in our iterative numerical procedure. We obtain consistent
transonic solutions in a wide range of values of the viscosity parameter alpha
and mass acretion rate. We compare two different form of viscosity: one takes
the shear stress to be proportional to the pressure, while the other uses the
angular velocity gradient-dependent stress.
  We find that there are two singular points in solutions corresponding to the
pressure-proportional shear stress. The inner singular point locates close to
the last stable orbit around black hole. This point changes its type from a
saddle to node depending on values of alpha and accretion rate. The outer
singular point locates at larger radius and is always of a saddle-type. We
argue that, contrary to the previous investigations, a nodal-type inner
singular point does not introduce multiple solutions. Only one integral curve,
which corresponds to the unique global solution, passes simultaneously the
inner and outer singular points independently of the type of inner singular
point. Solutions with the angular velocity gradient-dependent shear stress have
one singular point which is always of a saddle-type and corresponds to the
unique global solution. The structure of accretion disks corresponding to both
viscosities are similar.

</DOC>
<DOC>
<DOCNO> 39811 </DOCNO>
Search for New Particles Decaying to top-antitop in proton-antiproton


  We use 106 $\ipb$ of data collected with the Collider Detector at Fermilab to
search for narrow-width, vector particles decaying to a top and an anti-top
quark. Model independent upper limits on the cross section for narrow, vector
resonances decaying to $\ttbar$ are presented. At the 95% confidence level, we
exclude the existence of a leptophobic $\zpr$ boson in a model of
topcolor-assisted technicolor with mass $M_{\zpr}$ $<$ 480 $\gev$ for natural
width $\Gamma$ = 0.012 $M_{\zpr}$, and $M_{\zpr}$ $<$ 780 $\gev$ for $\Gamma$ =
0.04 $M_{\zpr}$.

</DOC>
<DOC>
<DOCNO> 151715 </DOCNO>
Long quantum superstrings in AdS_5 x S^5


  Following hep-th/0001204 we discuss the computation of quantum corrections
near long IIB superstring configurations in AdS_5 x S^5 which are related to
the Wilson loop expectation values in the strong coupling expansion of the dual
n=4 SYM theory with large N. We use the Green-Schwarz description of
superstrings in curved R-R backgrounds and demonstrate that it is well-defined
and useful for developing perturbation theory near long string backgrounds.

</DOC>
<DOC>
<DOCNO> 10336 </DOCNO>
Charge Current Density from the Scattering Matrix


  A method to derive the charge current density and its quantum mechanical
correlation from the scattering matrix is discussed for quantum scattering
systems described by a time-dependent Hamiltonian operator. The current density
and charge density are expressed with the help of functional derivatives with
respect to the vector potential and the electric potential. A condition imposed
by the requirement that these local quantities are gauge invariant is
considered. Our formulas lead to a direct relation between the local density of
states and the total current density at a given energy. To illustrate the
results we consider, as an example, a chiral ladder model.

</DOC>
<DOC>
<DOCNO> 121332 </DOCNO>
Mean Field Dynamo Saturation: Toward Understanding Conflicting Results


  Mean field dynamos may explain the origin of large scale magnetic fields of
galaxies, but controversy arises over the extent of dynamo quenching by the
growing field. Here we explain how apparently conflicting results may be
mutually consistent, by showing the role of magnetic helicity conservation and
boundary terms usually neglected. We estimate the associated magnetic energy
flowing out of the Galaxy but emphasize that the mechanism of field escape
needs to be addressed.

</DOC>
<DOC>
<DOCNO> 152302 </DOCNO>
Abelian and center gauge fixing in continuum Yang-Mills-Theory for


  A prescription for center gauge fixing for pure Yang-Mills theory in the
continuum with general gauge groups is presented. The emergence of various
types of singularities (magnetic monopoles and center vortices) appearing in
the course of the gauge fixing procedure are discussed.

</DOC>
<DOC>
<DOCNO> 102654 </DOCNO>
On Solutions of Three Quasi-Geostrophic Models


  We consider the 2D quasi-geostrophic model and its two different
regularizations. Global regularity results are established for the regularized
models with subcritical or critical indices. The proof of Onsager's conjecture
concerning weak solutions of the 3D Euler equations and the notion of
dissipative solutions of Duchon and Robert are extended to weak solutions of
the quasi-geostrophic equation.

</DOC>
<DOC>
<DOCNO> 117142 </DOCNO>
The Heats of Reactions. Calorimetry and Van't-Hoff. 1


  It has been supposed that the law of conservation of energy in chemical
reactions has the following form: dU=dQ-PdV+SUM Earlier the author has shown
that for the biggest part of reactions it must have the following form:
dU=dQ+PdV+SUM In the present paper this result is confirmed by other
experiments.

</DOC>
<DOC>
<DOCNO> 85240 </DOCNO>
Chaos in Non-Abelian Gauge Fields, Gravity, and Cosmology


  This talk describes the evolution of studies of chaos in Yang-Mills fields,
gravity, and cosmology. The main subject is a BKL regime near the singularity
$t=0$ and its survival in higher dimensions and in string theory. We also
describe the recent progress in the search for particle-like solutions of the
Einstein-Yang-Mills system (monopoles and dyons), colored black holes and the
problem of their stability.

</DOC>
<DOC>
<DOCNO> 9927 </DOCNO>
Spin Degeneracy and Conductance Fluctuations in Open Quantum Dots


  The dependence of mesoscopic conductance fluctuations on parallel magnetic
field is used as a probe of spin degeneracy in open GaAs quantum dots. The
variance of fluctuations at high parallel field is reduced from the low-field
variance (with broken time-reversal symmetry) by factors ranging from roughly
two in a 1 square-micron dot at low temperature, to four or greater in 8
square-micron dots. The factor of two is expected for simple Zeeman splitting
of spin degenerate channels. A possible explanation for the unexpected larger
factors in terms of field-dependent spin orbit scattering is proposed.

</DOC>
<DOC>
<DOCNO> 174612 </DOCNO>
Neutral Pions and Eta Mesons as Probes of the Hadronic Fireball in


  Chemical and thermal freeze-out of the hadronic fireball formed in symmetric
collisions of light, intermediate-mass, and heavy nuclei at beam energies
between 0.8A GeV and 2.0A GeV are discussed in terms of an equilibrated,
isospin-symmetric ideal hadron gas with grand-canonical baryon-number
conservation. For each collision system the baryochemical potential mu_B and
the chemical freeze-out temperature T_c are deduced from the inclusive neutral
pion and eta yields which are augmented by interpolated data on deuteron
production. With increasing beam energy mu_B drops from 800 MeV to 650 MeV,
while T_c rises from 55 MeV to 90 MeV. For given beam energy mu_B grows with
system size, whereas T_c remains constant. The centrality dependence of the
freeze-out parameters is weak as exemplified by the system Au+Au at 0.8A GeV.
For the highest beam energies the fraction of nucleons excited to resonance
states reaches freeze-out values of nearly 15 %, suggesting resonance densities
close to normal nuclear density at maximum compression. In contrast to the
particle yields, which convey the status at chemical freeze-out, the shapes of
the related transverse-mass spectra do reflect thermal freeze-out. The observed
thermal freeze-out temperatures T_th are equal to or slightly lower than T_c,
indicative of nearly simultaneous chemical and thermal freeze-out.

</DOC>
<DOC>
<DOCNO> 116588 </DOCNO>
Relativity as the quantum mechanics of space-time measurements


  Can a simple microscopic model of space and time demonstrate Special
Relativity as the macroscopic (aggregate) behavior of an ensemble ? The
question will be investigated in three parts. First, it is shown that the
Lorentz transformation formally stems from the First Relativity Postulate (FRP)
{\it alone} if space-time quantization is a fundamental law of physics which
must be included as part of the Postulate. An important corollary, however, is
that when measuring devices which carry the basic units of lengths and time
(e.g. a clock ticking every time quantum) are `moving' uniformly, they appear
to be measuring with larger units. Secondly, such an apparent increase in the
sizes of the quanta can be attributed to extra fluctuations associated with
motion, which are precisely described in terms of a thermally agitated harmonic
oscillator by using a temperature parameter. This provides a stringent
constraint on the microscopic properties of flat space-time: it is an array of
quantized oscillators. Thirdly, since the foregoing development would suggest
that the space-time array of an accelerated frame cannot be in thermal
equilibrium, (i.e. it will have a distribution of temperatures), the approach
is applied to the case of acceleration by the field of {\it any} point object,
which corresponds to a temperature `spike' in the array. It is shown that the
outward transport of energy by phonon conduction implies an inverse-square law
of force at low speeds, and the full Schwarzschild metric at high speeds. A
prediction of the new theory is that when two inertial observers move too fast
relative to each other, or when fields are too strong, anharmonic corrections
will modify effects like time dilation, and will lead to asymmetries which
implies that the FRP may not be sustainable in this extreme limit.

</DOC>
<DOC>
<DOCNO> 68292 </DOCNO>
Theory of rare kaon decays


  We review some recent theoretical results on rare kaon decays. Particular
attention is devoted to find Standard Model tests. This is theoretically easy
in $K\to \pi \nu \bar{\nu}$, while a careful study of the long distance
contributions is needed for $K_{L}\to \pi ^{0}e% \bar{e}$, $K_{L}\to \mu
\bar{\mu}$ and $K\to \pi \pi \gamma$

</DOC>
<DOC>
<DOCNO> 12159 </DOCNO>
Critical dimensions of the diffusion equation


  We study the evolution of a random initial field under pure diffusion in
various space dimensions. From numerical calculations we find that the
persistence properties of the system show sharp transitions at critical
dimensions d1 ~ 26 and d2 ~ 46. We also give refined measurements of the
persistence exponents for low dimensions.

</DOC>
<DOC>
<DOCNO> 119753 </DOCNO>
Asteroids in the Inner Solar System I - Existence


  Ensembles of in-plane and inclined orbits in the vicinity of the Lagrange
points of the terrestrial planets are integrated for up to 100 million years.
The integrations incorporate the gravitational effects of Sun and the eight
planets (Pluto is neglected). Mercury is the least likely planet, as it is
unable to retain tadpole orbits over 100 million year timescales. Both Venus
and the Earth are much more promising, as they possess rich families of stable
tadpole and horseshoe orbits. Our survey of Trojans in the orbital plane of
Venus is undertaken for 25 million years. Some 40% of the survivors are on
tadpole orbits. For the Earth, the integrations are pursued for 50 million
years. The stable zones in the orbital plane are larger for the Earth than for
Venus, but fewer of the survivors are tadpoles. Both Venus and the Earth also
have regions in which inclined test particles can endure near the Lagrange
points. For Venus, only test particles close to the orbital plane are stable.
For the Earth, there are two bands of stability, one at low inclinations (i <
16 degrees) and one at moderate inclinations (between 24 degrees and 34
degrees). The inclined test particles that evade close encounters are primarily
moving on tadpole orbits. Our survey of in-plane test particles near the
Martian Lagrange points shows no survivors after 60 million years. Low
inclination test particles do not persist, as their inclinations are quickly
increased until the effects of a secular resonance with Jupiter cause
de-stabilisation. Numerical integrations of inclined test particles for
timespans of 25 million years show stable zones for inclinations between 14 and
40 degrees.

</DOC>
<DOC>
<DOCNO> 84445 </DOCNO>
Homogeneous magnetic fields in fully anisotropic string cosmological


  We present new solutions of the string cosmological effective action in the
presence of a homogeneous Maxwell field with pure magnetic component. Exact
solutions are derived in the case of space-independent dilaton and vanishing
torsion background. In our examples the four dimensional metric is either of
Bianchi-type III and VI$_{-1}$ or Kantowski-Sachs.

</DOC>
<DOC>
<DOCNO> 70718 </DOCNO>
Time-Like Extra Dimension and Cosmological Constant in Brane Models


  We discuss the general models with one time-like extra dimension and parallel
3-branes on the space-time $M^4 \times M^1$. We also construct the general
brane models or networks with $n$ space-like and $m$ time-like extra dimensions
and with constant bulk cosmological constant on the space-time $M^4\times
(M^1)^{n+m}$, and point out that there exist two kinds of models with zero bulk
cosmological constant: for static solutions, we have to introduce time-like and
space-like extra dimensions, and for non-static solutions, we can obtain the
models with only space-like extra dimension(s). In addition, we give two
simplest models explicitly, and comment on the 4-dimensional effective
cosmological constant.

</DOC>
<DOC>
<DOCNO> 69931 </DOCNO>
Measuring sparticle masses in non-universal string inspired models at


  We demonstrate that some of the suggested five supergravity points for study
at the LHC could be approximately derived from perturbative string theories or
M-theory, but that charge and colour breaking minima would result. As a pilot
study, we then analyse a perturbative string model with non-universal soft
masses that are optimised in order to avoid global charge and colour breaking
minima. By combining measurements of up to six kinematic edges from squark
decay chains with data from a new kinematic variable, designed to improve
slepton mass measurements, we demonstrate that a typical LHC experiment will be
able to determine squark, slepton and neutralino masses with an accuracy
sufficient to permit an optimised model to be distinguished from a similar
standard SUGRA point. The technique thus generalizes SUSY searches at the LHC.

</DOC>
<DOC>
<DOCNO> 72160 </DOCNO>
Improving alpha_QED(M_Z^2) and the charm mass by analytic continuation


  The standard determination of the QED coupling on the Z pole is performed
using the latest available data for R. The direct application of analytic
continuation techniques is found not to improve the accuracy of the value of
\alpha(M_Z^2). However they help to resolve an ambiguity in the values of R in
the energy region \sqrt{s} < 2 GeV, which, in turn, reduces the uncertainty in
\alpha(M_Z^2). Moreover, they provide a sensitive determination of the mass of
the charm quark. The favoured solution, which uses the inclusive data for R for
\sqrt{s} < 2 GeV, has a pole mass m_c = 1.33-1.40 GeV and \alpha^{-1}(M_Z^2) =
128.972 +/- 0.026; whereas if the sum of the exclusive channels is used to
determine R in this region, we find \alpha^{-1}(M_Z^2) = 128.941 +/- 0.029.

</DOC>
<DOC>
<DOCNO> 68942 </DOCNO>
Inverse meson mass ordering in color-flavor-locking phase of high


  We correct a mistake in the calculation of meson masses at large baryon
chemical potential made in hep-ph/9910491v2

</DOC>
<DOC>
<DOCNO> 8256 </DOCNO>
Shapes, contact angles, and line tensions of droplets on cylinders


  Using an interface displacement model we calculate the shapes of
nanometer-size liquid droplets on homogeneous cylindrical surfaces. We
determine effective contact angles and line tensions, the latter defined as
excess free energies per unit length associated with the two contact lines at
the ends of the droplet. The dependences of these quantities on the cylinder
radius and on the volume of the droplets are analyzed.

</DOC>
<DOC>
<DOCNO> 151071 </DOCNO>
On the global calculus in local cohomology in BRST theory


  We show that the cohomology groups of the horizontal (total) differential on
horizontal (local) exterior forms on the infinite-order jet manifold of an
affine bundle coincide with the De Rham cohomology groups of the base manifold.
This prevents one from the topological obstruction to the definition of global
descent equations in BRST theory on an arbitrary affine bundle.

</DOC>
<DOC>
<DOCNO> 116666 </DOCNO>
On the integration accuracy in molecular density functional theory


  The sensitivity of computed DFT (Density Functional Theory) molecular
properties (including energetics, geometries, vibrational frequencies, and
infrared intensities) to the radial and angular numerical integration grid
meshes, as well as to the partitioning scheme, is discussed for a number of
molecules using the Gaussian 98 program system. Problems with typical
production grid sizes are particularly acute for third-row transition metal
systems, but may still result in qualitatively incorrect results for a molecule
as simple as CCH. Practical recommendations are made with respect to grid
choices for the energy(+gradient) steps, as well as for the solution of the
CPKS (Coupled Perturbed Kohn-Sham) equations.

</DOC>
<DOC>
<DOCNO> 71537 </DOCNO>
The Challenge of Light-Front Quantisation: Recent Results


  We explain what is the challenge of light-front quantisation, and how we can
now answer it because of recent progress in solving the problem of zero modes
in the case of non-Abelian gauge theories. We also give a description of the
light-front Hamiltonian for SU(2) finite volume gluodynamics resulting from
this recent solution to the problem of light-front zero modes.

</DOC>
<DOC>
<DOCNO> 68276 </DOCNO>
Double Higgs production at TeV Colliders in the Minimal Supersymmetric


  The reconstruction of the Higgs potential in the Minimal Supersymmetric
Standard Model (MSSM) requires the measurement of the trilinear Higgs
self-couplings. The `double Higgs production' subgroup has been investigating
the possibility of detecting signatures of processes carrying a dependence on
these vertices at the Large Hadron Collider (LHC) and future Linear Colliders
(LCs). As reference reactions, we have chosen $gg\to hh$ and $e^+e^-\to h h Z$,
respectively, where $h$ is the lightest of the MSSM Higgs bosons. In both
cases, the $Hhh$ interaction is involved. For $m_H>2m_h$, the two reactions are
resonant in the $H\to hh$ mode, providing cross sections which are detectable
at both accelerators and strongly sensitive to the strength of the trilinear
coupling involved. We explore this mass regime of the MSSM in the $h\to b\bar
b$ decay channel, also accounting for irreducible background effects.

</DOC>
<DOC>
<DOCNO> 119767 </DOCNO>
Confirmation of a moving component in the H-alpha emission line of


  We report our attempts to detect and confirm a narrow moving component in the
H-alpha emission line of the radio emitting Be/X-ray binary LSI+61 303 (V615
Cas, GT0236+610). The existence of this spectral feature was already suspected
in the past. As a result, we find that this component does exist and that its
radial velocity varies in agreement with the radio period of the system. We
interpret it tentatively as due to a denser region, or bulge, orbiting near the
outer edge of the H-alpha emitting disk.

</DOC>
<DOC>
<DOCNO> 151568 </DOCNO>
From quiver diagrams to particle physics


  Recent scenarios of phenomenologically realistic string compactifications
involve the existence of gauge sectors localized on D-branes at singular points
of Calabi-Yau threefolds. The spectrum and interactions in these gauge sectors
are determined by the local geometry of the singularity, and can be encoded in
quiver diagrams. We discuss the physical models arising for the simplest case
of orbifold singularities, and generalize to non-orbifold singularities and
orientifold singularities. Finally we show that relatively simple singularities
lead to gauge sectors surprisingly close to the standard model of elementary
particles.

</DOC>
<DOC>
<DOCNO> 122542 </DOCNO>
High resolution X-Ray spectroscopy of Zeta Puppis with the XMM-Newton


  We present the first high resolution X-ray spectrum of the bright O4Ief
supergiant star Zeta Puppis, obtained with the Reflection Grating Spectrometer
on-board XMM-Newton. The spectrum exhibits bright emission lines of
hydrogen-like and helium-like ions of nitrogen, oxygen, neon, magnesium, and
silicon, as well as neon-like ions of iron. The lines are all significantly
resolved, with characteristic velocity widths of order 1000-1500 km s^{-1}. The
nitrogen lines are especially strong, and indicate that the shocked gas in the
wind is mixed with CNO-burned material, as has been previously inferred for the
atmosphere of this star from ultraviolet spectra. We find that the forbidden to
intercombination line ratios within the helium-like triplets are anomalously
low for N VI, O VII, and Ne IX. While this is sometimes indicative of high
electron density, we show that in this case, it is instead caused by the
intense ultraviolet radiation field of the star. We use this interpretation to
derive constraints on the location of the X-ray emitting shocks within the wind
that are consistent with current theoretical models for this system.

</DOC>
<DOC>
<DOCNO> 12974 </DOCNO>
Superconducting crossed correlations in ferromagnets: implications for


  It is demonstrated that non local Cooper pairs can propagate in ferromagnetic
electrodes having an opposite spin orientation. In the presence of such crossed
correlations, the superconducting gap is found to depend explicitly on the
relative orientation of the ferromagnetic electrodes. Non local Cooper pairs
can in principle be probed with dc-transport. With two ferromagnetic
electrodes, we propose a ``quantum switch'' that can be used to detect
correlated pairs of electrons. With three or more ferromagnetic electrodes, the
Cooper pair-like state is a linear superposition of Cooper pairs which could be
detected in dc-transport. The effect also induces an enhancement of the
ferromagnetic proximity effect on the basis of crossed superconducting
correlations propagating along domain walls.

</DOC>
<DOC>
<DOCNO> 101820 </DOCNO>
The Hanna Neumann Conjecture is true when one subgroup has a positive


  The Hanna Neumann conjecture states that if F is a free group, then for all
finitely generated subgroups H,K <= F, rank(H intersect K) - 1 <= [ rank(H)-1 ]
[ rank(K)-1 ] In this paper, we show that if one of the subgroups, say H, has a
generating set consisting of only positive words, then H is not part of any
counterexample to the conjecture. We further show that if H <= F({a,b}) is part
of a counterexample to the conjecture, then its folding Gamma_H must contain
source and/or sink vertices.

</DOC>
<DOC>
<DOCNO> 170698 </DOCNO>
Singular potentials and absorption problem in Quantum Mechanics


  We discuss a possible approach to the absorption problem in Quantum Mechanics
based on using of singular attractive potentials in the corresponding
Schr\"{o}dinger equations. Possible criteria for selection of exact solutions
of these equations are considered and it is shown that different models of
absorption can be realized by a special choice of exact solutions. As an
example, the motion of charged particles in the Aharonov-Bohm (AB) and the
scalar attractive $\rho^{-2}$ potentials is investigated in detail. Other
attractive potentials are briefly considered.

</DOC>
<DOC>
<DOCNO> 178384 </DOCNO>
Description of quadrupole collectivity in N ~ 20 nuclei with techniques


  Properties of the ground and several collective excited states of the light
nuclei ^{30,32,34}Mg are described in the framework of the angular momentum
projected Generator Coordinate Method using the quadrupole moment as collective
coordinate and the Gogny force as the effective interaction. The calculated
excitation energies and B(E2) transition probabilities agree reasonably well
with experiment. The results clearly indicate that both the restoration of the
rotational symmetry and the quadrupole dynamics are key ingredients for the
description of the properties of the above mentioned nuclei.

</DOC>
<DOC>
<DOCNO> 121942 </DOCNO>
Truncations in stellar disks


  The presence of radial truncations in stellar disks is reviewed. There is
ample evidence that many disk galaxies have relatively shaprt truncations in
their disks. These often are symmetric and independent of the wavelength band
of the observations. The ratio of the truncation radius R_{max} to the disk
scalelength h appears often less then 4.5, as expected on a simple model for
the disk collapse. Current samples of galaxies observed may however not be
representative and heavily biased towards disks with the largest scalelengths.
Many spiral galaxies also have HI warps and these generally start at the
truncation radius of the stellar disk. The HI surface density suddenly becomes
much flatter with radius. In some galaxies the start of the warp and the
position of the disk truncation radius is accompanied by a drop in the rotation
velocity. In the regiosn beyond the dis truncation in the HI layer some star
formation does occur, but the heavy element abundance and the dust content are
very low. All evidence is consistent with the notion that the outer gas parts
of the disks constitute recently accreted material, at least accreted after
formation of what is now the stellar thin disk. Although various models exist
for the origin of the truncations in the stellar disks, this at present remains
unclear.

</DOC>
<DOC>
<DOCNO> 83064 </DOCNO>
Measures of Distributional Similarity


  We study distributional similarity measures for the purpose of improving
probability estimation for unseen cooccurrences. Our contributions are
three-fold: an empirical comparison of a broad range of measures; a
classification of similarity functions based on the information that they
incorporate; and the introduction of a novel function that is superior at
evaluating potential proxy distributions.

</DOC>
<DOC>
<DOCNO> 116459 </DOCNO>
Elementary Quantum Mechanics


  This is the first graduate course on elementary quantum mechanics in Internet
written in Romanian for the benefit of Romanian speaking students (Romania and
Moldova). It is a translation (with corrections) of the Spanish version of the
course (physics/9808031, English translation physics/0004072), which I did at
the request of students of physics in Bucharest. The topics included refer to
the postulates of quantum mechanics, one-dimensional barriers and wells,
angular momentum and spin, WKB method, harmonic oscillator, hydrogen atom,
quantum scattering, and partial waves

</DOC>
<DOC>
<DOCNO> 121630 </DOCNO>
Peculiar velocities of galaxies and clusters


  We present a simple model for the shape of the distribution function of
galaxy peculiar velocities. We show how both nonlinear and linear theory terms
combine to produce a distribution which has an approximately Gaussian core with
exponential wings. The model is easily extended to study how the statistic
depends on the type of particle used to trace the velocity field (dark matter
particles, dark matter haloes, galaxies), and on the density of the environment
in which the test particles are. Comparisons with simulations suggest that our
model is accurate. We also show that the evolution of the peculiar velocities
depends on the local, rather than the global density. Since clusters populate
denser regions on average, using cluster velocities with the linear theory
scaling may lead to an overestimate of the global value of Omega. Conversely,
using linear theory with the global value of Omega to scale cluster velocities
from the initial to the present time results in an underestimate of their true
velocities. In general, however, the directions of motions of haloes are rather
well described by linear theory. Our results help to simplify models of
redshift-space distortions considerably.

</DOC>
<DOC>
<DOCNO> 121049 </DOCNO>
S 10947 Aql = RX J2009.8+1557: A probable RS CVn star which sometimes


  We report the discovery of a new variable star, called S 10947 Aql, as the
likely optical counterpart of RX J2009.8+1557. The optical variability pattern
as well as the detected X-ray emission suggest that it is a chromospherically
active binary of the RS Canum Venaticorum type. We discovered an occasional
disappearance of the eclipsing minima as well as large variations in the
eclipse amplitude. We discuss possible causes of this peculiarity.

</DOC>
<DOC>
<DOCNO> 151653 </DOCNO>
Renormalization Group Flow in BRST Invariant Open String $\sigma$-Model


  The renormalization group flow in the theory space of a BRST invariant string
$\sigma$-model is investigated. For the open bosonic string the
non-perturbative off-shell effective action and its gauge symmetry properties
are determined from $\beta$-functions defined by the local Weyl anomaly. The
interactions are shown to explicitly break the free theory BRST invariance
generating new non-linear gauge symmetries of the type present in Witten's
string field theory. In the Feynman-Siegel gauge the $\sigma$-model is shown to
generate Witten's structure of vertex couplings.

</DOC>
<DOC>
<DOCNO> 72270 </DOCNO>
Nonlinear effects in Compton scattering at photon colliders


  The backward Compton scattering is a basic process at future higher energy
photon colliders. To obtain a high probability of e->gamma conversion the
density of laser photons in the conversion region should be so high that
simultaneous interaction of one electron with several laser photons is possible
(nonlinear Compton effect). In this paper a detailed consideration of energy
spectra, helicities of final photons and electrons in nonlinear backward
Compton scattering of circularly polarized laser photons is given.
Distributions of gamma-gamma luminosities with total helicities 0 and 2 are
investigated. Very high intensity of laser wave leads to broadening of the
energy (luminosity) spectra and shift to lower energies (invariant masses).
Beside complicated exact formulae, approximate formulae for energy spectrum and
polarization of backscattered photons are given for relatively small nonlinear
parameter xi^2 (first order correction). All this is necessary for optimization
of the conversion region at photon colliders and study of physics processes
where a sharp edge of the luminosity spectrum and monochromaticity of
collisions are important.

</DOC>
<DOC>
<DOCNO> 170568 </DOCNO>
Finding Solutions to NP Problems: Philosophical Difference Between


  There is no known polynomial-time algorithm that can solve an NP problem.
Evolutionary search has been shown to be a viable method of finding acceptable
solutions within a reasonable time period. Recently quantum computers have
surfaced as another alternative method. But these two methods use radically
different philosophies for solving NP problems even though both search methods
are non-deterministic. This paper uses instances of {\bf SAT}, {\bf 3SAT} and
{\bf TSP} to describe how these two methods differ in their approach to solving
NP problems.

</DOC>
<DOC>
<DOCNO> 121677 </DOCNO>
K band Spectroscopy of Ultraluminous Infrared Galaxies: The 2 Jy Sample


  We present near-infrared spectroscopy for a complete sample of 33
ultraluminous infrared galaxies at a resolution of R\approx 1000. Most of the
wavelength range from 1.80-2.20 microns in the rest frame is covered, including
the Pa-alpha and Br-gamma hydrogen recombination lines, and the molecular
hydrogen vibration-rotation 1-0 S(1) and S(3) lines. Other species, such as He
I, [Fe II], and [Si VI] appear in the spectra as well, in addition to a number
of weaker molecular hydrogen lines. Nuclear extractions for each of the
individual galaxies are presented here, along with spectra of secondary nuclei,
where available. The Pa-alpha emission is seen to be highly concentrated on the
nuclei, typically with very little emision extending beyond a radius of 1 kpc.
Signatures of active nuclei are rare in the present sample, occurring in only
two of the 33 galaxies. It is found that visual extinctions to the nuclei via
the Pa-alpha/Br-gamma line ratio in excess of 10 magnitudes are relatively
common among ULIRGs, and that visual extinctions greater than 25 mag are
necessary to conceal a QSO emitting half the total bolometric luminosity. The
vibration-rotation lines of molecular hydrogen appear to be predominantly
thermal in origin, with effective temperatures generally around 2200 K. The
relative nuclear velocities between double nucleus ULIRGs are investigated,
through which it is inferred that the maximum deprojected velocity difference
is about 200 km/s. This figure is lower than the velocities predicted by
physical models of strong interactions/mergers of large, gas-rich galaxies.

</DOC>
<DOC>
<DOCNO> 12135 </DOCNO>
Incomplete statistics and nonextensive generalization of statistical


  Statistical mechanics is generalized on the basis of an information theory
for inexact or incomplete probability distributions. A parameterized
normalization is proposed and leads to a nonextensive entropy. The resulting
incomplete statistical mechanics is proved to have the same theoretical
characteristics as Tsallis one based on the conventional normalization.

</DOC>
<DOC>
<DOCNO> 68765 </DOCNO>
Next-to-leading Order Calculation of the Color-Octet 3S1 Gluon


  The short-distance coefficients for the color-octet 3S1 term in the
fragmentation function for a gluon to split into heavy quarkonium states is
calculated to order alpha_s^2. The gauge-invariant definition of the
fragmentation function by Collins and Soper is employed. Ultraviolet
divergences are removed using the MS-bar renormalization procedure. The
longitudinal term in the fragmentation function agrees with a previous
calculation by Beneke and Rothstein. The next-to-leading order correction to
the transverse term disagrees with a previous calculation.

</DOC>
<DOC>
<DOCNO> 151282 </DOCNO>
Non abelian N=2 supersymmetric Born Infeld action


  We present a N=2 supersymmetric action for the Born Infeld theory in the non
abelian case. We quantize the theory in N=1 superspace and compute divergences
at one-loop. The result is discussed in the N=4 case.

</DOC>
<DOC>
<DOCNO> 39845 </DOCNO>
Many pion decays of rho(770) and omega(782) mesons in chiral theory


  The decays rho(770) to 4 pi and omega(782) to 5pi are considered in detail in
the approach based on the Weinberg Lagrangian obtained upon the nonlinear
realization of chiral symmetry, added with the term induced by the anomalous
Lagrangian of Wess and Zumino. The partial widths and excitation curves of the
decays rho^0 to 2 pi^+ 2 pi^-, pi^+ pi^- 2 pi^0, rho^{+-} to 2 pi^{+-} pi^{-+}
pi^0, rho^(+-} to pi^(+-} 3 pi^0 are evaluated for e^+e^- annihilation,
photoproduction and tau lepton decays. The results of calculations are compared
with the recent CMD-2 data on the decay rho^0 to 2 pi^+ 2 pi^- observed in
e^+e^- annihilation. The omega to 5 pi decay widths and excitation curves in
e^+e^- annihilation are obtained. The angular distributions for various
combinations of the final pions in the decays rho to 4 pi and omega to 5 pi are
written. The perspectives of the experimental study of the above decays in
e^+e^- annihilation, tau lepton decays and photoproduction are discussed.

</DOC>
<DOC>
<DOCNO> 170513 </DOCNO>
Semiclassical description of Stern-Gerlach experiments


  The motion of neutral particles with magnetic moments in an inhomogeneous
magnetic field is described in a semi-classical framework. The concept of
Coherent Internal States is used in the formulation of the semiclassical
approximation from the full quantum mechanical expression. The classical
trajectories are defined only for certain spin state, that satusfy the
conditions for being Coherent Internal State. The raalibility of Stern-Gerlach
experiments to measure spin projectons is assessed in this framework.

</DOC>
<DOC>
<DOCNO> 84227 </DOCNO>
Maxwell equation, Shroedinger equation, Dirac equation, Einstein


  What forms will have an equations of modern physics if the dimensions of our
time and space are fractional? The generalized equations enumerated by title
are presented by help the generalized fractional derivatives of
Riemann-Liouville.

</DOC>
<DOC>
<DOCNO> 10978 </DOCNO>
Magetoresistance of RuO_2-based resistance thermometers below 0.3 K


  We have determined the magnetoresistance of RuO_2-based resistors (Scientific
Instruments RO-600) between 0.05 K and 0.3 K in magnetic fields up to 8 T. The
magnetoresistance is negative around 0.5 T and then becomes positive at larger
fields. The magnitude of the negative magnetoresistance increases rapidly as
the temperature is lowered, while that of the positive magnetoresistance has
smaller temperature dependence. We have also examined the temperature
dependence of the resistance below 50 mK in zero magnetic field. It is
described in the context of variable-range-hopping conduction down to 15 mK.
Hence, the resistors can be used as thermometers down to at least 15 mK.

</DOC>
<DOC>
<DOCNO> 120922 </DOCNO>
A Statistical Study of Emission Lines from High Redshift Radio Galaxies


  We have compiled a sample of 165 radio galaxies from the literature to study
the properties of the extended emission line regions and their interaction with
the radio source over a large range of redshift 0<z<5.2. For each source, we
have collected radio (size, lobe distance ratio and power) and spectroscopic
parameters (luminosity, line width and equivalent width) for the four brightest
UV lines. We also introduce a parameter A_{Ly-alpha} measuring the asymmetry of
the Ly-alpha line. Using these 18 parameters, we examine the statistical
significance of all 153 mutual correlations, and find the following significant
correlations: (i) Ly-alpha asymmetry A_{Ly-alpha} with radio size and redshift,
(ii) line luminosity with radio power, (iii) line luminosities of UV lines with
each other, and (iv) equivalent widths of UV lines with each other. Using
line-ratio diagnostic diagrams, we examine the ionization mechanism of the
extended emission line regions in HzRGs. The high ionization lines seem to
confirm previous results showing that AGN photo-ionization provides the best
fit to the data, but are inconsitent with the CII/CIII ratio, which favour the
highest velocity shock ionization models. We note that the CII line is 5 times
more sensitive to shock ionization than the high ionization UV lines, and show
that a combination of shock and photo-ionization provides a better overall fit
to the integrated spectra of HzRGs. Because most HzRGs have radio sizes <~150
kpc, their integrated spectra might well contain a significant contribution
from shock ionized emission. [abridged]

</DOC>
<DOC>
<DOCNO> 8147 </DOCNO>
Anderson localization in bipartite lattices


  We study the localization properties of a disordered tight-binding
Hamiltonian on a generic bipartite lattice close to the band center. By means
of a fermionic replica trick method, we derive the effective non-linear
$\sigma$-model describing the diffusive modes, which we analyse by using the
Wilson--Polyakov renormalization group. In addition to the standard parameters
which define the non-linear $\sigma$-model, namely the conductance and the
external frequency, a new parameter enters, which may be related to the
fluctuations of the staggered density of states. We find that, when both the
regular hopping and the disorder only couple one sublattice to the other, the
quantum corrections to the Kubo conductivity vanish at the band center, thus
implying the existence of delocalized states. In two dimensions, the RG
equations predict that the conductance flows to a finite value, while both the
density of states and the staggered density of states fluctuations diverge. In
three dimensions, we find that, for arbitrarily weak disorder, sufficiently
close to the band center, all states are extended. We also discuss the role of
various symmetry breaking terms, as a regular hopping between same sublattices,
or an on-site disorder.

</DOC>
<DOC>
<DOCNO> 71145 </DOCNO>
O(alpha^3 ln alpha) corrections to muonium and positronium hyperfine


  We compute O(alpha^3 ln alpha) relative corrections to the ground state
hyperfine splitting of a QED two body bound state with different masses of
constituents. The general result is then applied to muonium and positronium. In
particular, a new value of the muon to electron mass ratio is derived from the
muonium ground state hyperfine splitting.

</DOC>
<DOC>
<DOCNO> 101053 </DOCNO>
Non Complete Affine Connections on Filiform Lie Groups


  We give some examples of non-complete invariant affine connections on
nilpotent and filiform Lie groups. This permits to describe non-nilpotent
faithful representations on the model of filiform n-dimensional Lie algebras
and, in particular, on the 3 dimensional Heisenberg algebra.

</DOC>
<DOC>
<DOCNO> 40141 </DOCNO>
Effective description of quark mixing


  We use the effective Lagrangian formalism to describe quark mixing. The new
W, Z and H couplings generalizing the CKM matrix and the GIM mechanism fulfil
relations and inequalities which allow to discriminate among different SM
extensions. As a by-product we give a useful parametrization of the generalized
CKM matrix. We also show that the largest possible departures from the SM
predictions result from heavy exotic fermions, which can induce, for example,
top FCNC large enough to be observable at future colliders.

</DOC>
<DOC>
<DOCNO> 40049 </DOCNO>
Lepton Flavour Violation at HERA


  The $e^+p$-data collected with the ZEUS (${\cal L}=47.7$ pb$^{-1}$) and the
H1 (${\cal L}=37$ pb$^{-1}$) detectors at HERA in 1994--1997 are analysed for
signals of lepton flavour violation mediated by leptoquark exchange, both in
the muon and the tau channels. No evidence for lepton flavour violation is
found and limits on the leptoquarks' Yukawa couplings are set.

</DOC>
<DOC>
<DOCNO> 117099 </DOCNO>
p/e Geometric Mass Ratio


  A previously proposed geometric definition of mass in terms of energy, in a
geometrical unified theory, is used to obtain a numerical expression for a
ratio of masses of geometrical excitations. The resultant geometric ratio is
approximately equal the ratio of the proton to electron physical masses.

</DOC>
<DOC>
<DOCNO> 69241 </DOCNO>
Two-Loop QCD Anomalous Dimensions of Flavour-Changing Four-Quark


  We calculate the two-loop QCD anomalous dimension matrix (ADM) gamma^(1)_NDR
in the NDR-MSbar scheme for all the flavour-changing four-quark dimension-six
operators that are relevant in both the Standard Model and its extensions. Both
current-current and penguin diagrams are included. Some of our NDR-MSbar
results for Delta F=1 operators overlap with the previous calculations, but
several others have never been published before. In the case of Delta F=2
operators, our results are compatible with the ones obtained by Ciuchini et al.
in the Regularization-Independent renormalization scheme, but differ from their
NDR-MSbar results. In order to explain the difference, we calculate the ADM of
Delta F=2 operators again, extracting it from the ADM of Delta F=1 operators.

</DOC>
<DOC>
<DOCNO> 71426 </DOCNO>
Final State Interactions and eps'/eps


  I discuss the role of strong final state interactions (FSI) in K \to 2\pi
decays. In this case strong FSI effects can be resummed [1,2] by solving the
Omn\`es problem for K\to 2\pi amplitudes. Implications for the CP conserving
Delta I=1/2 ratio and the direct CP violation parameter eps'/eps are also
discussed.

</DOC>
<DOC>
<DOCNO> 102758 </DOCNO>
Degenerations of Schubert varieties of SL(n)/B to toric varities


  Using polytopes defined in an earlier paper, we show in this paper the
existence of degenerations of a large class of Schubert varieties of SL_n to
toric varieties by extending the method used by Gonciulea and Lakshmibai for a
minuscule G/P to Schubert varieties in SL_n

</DOC>
<DOC>
<DOCNO> 99719 </DOCNO>
Maps of surface groups to finite groups with no simple loops in the


  Let $F_g$ denote the closed orientable surface of genus $g$. What is the
least order finite group, $G_g$, for which there is a homomorphism $\psi$ from
$\pi_1(F_g)$ to $G_g$ so that no nontrivial simple closed curve on $F_g$
represents an element in Ker($\psi$)? For the torus it is easily seen that $G_1
= Z_2 \times Z_2$ suffices. We prove here that $G_2$ is a group of order 32 and
that an upper bound for the order of $G_g$ is given by $g^{2g +1}$. The
previously known upper bound was greater than $2^{g{2^{2g}}}$.

</DOC>
<DOC>
<DOCNO> 121173 </DOCNO>
Rayleigh-Taylor stability of a strong vertical magnetic field at the


  Observations of narrow radio-emitting filaments near the Galactic center have
been interpreted in previous studies as evidence of a pervasive vertical (i.e.
perpendicular to the Galactic plane) milliGauss magnetic field in the central
150 pc of the Galaxy. A simple cylindrically symmetric model for the
equilibrium in this central region is proposed in which horizontal (i.e.
parallel to the Galactic plane) magnetic fields embedded in an annular band of
partially ionized molecular material of radius 150 pc are wrapped around
vertical magnetic fields threading low-density hot plasma. The central vertical
magnetic field, which has a pressure that significantly exceeds the thermal
pressure of the medium, is confined by the weight of the molecular material.
The stability of this equilibrium is studied indirectly by analyzing a
uniformly rotating cylinder of infinite extent along the z axis in cylindrical
coordinates (r,theta,z), with low-density plasma and an axial magnetic field at
r< 150 pc, high-density plasma and an azimuthal field at r> 150 pc, and a
gravitational acceleration g* proportional to r directed in the negative-r-hat
direction. The density profile and gravity tend to destabilize the plasma, but
the plasma tends to be stabilized by rotation and magnetic tension--since the
interface between the high and low-density plasmas can not be perturbed without
bending either the horizontal or vertical field. It is shown analytically that
when beta= 8(pi)p/B^2 is small and the dense plasma is supported against
gravity primarily by rotation, the necessary and sufficient condition for
stability to k_z=0 modes is |g| < (2|Omega| a), where g = g* - Omega^2 r is the
effective gravity, Omega is the uniform angular velocity, and "a" is the sound
speed in the dense plasma.

</DOC>
<DOC>
<DOCNO> 13897 </DOCNO>
The phase diagram of the lattice Calogero-Sutherland model


  We introduce a {\it lattice} version of the Calogero Sutherland model adapted
to describe $1/d^2$ pairwise interacting steps with discrete positions on a
vicinal surface. The configurational free energy is obtained within a transfer
matrix method. The full phase diagram for attractive and for repulsive
interaction is deduced. For attraction, critical temperatures of faceting
transitions are found to depend on step density.

</DOC>
<DOC>
<DOCNO> 10326 </DOCNO>
Critical Resistivity along the Quantum Hall Liquid--Insulator Transition


  The critical resistivity measured along the quantum Hall liquid--insulator
transition line indicates a pronounced peak at a critical filling factor close
to 1, which marks the crossover from the high to low magnetic field regime in
the phase diagram. The origin of this behavior is explained in the framework of
classical transport in a puddle network model. The proposed scenario is also
consistent with the behavior of the critical Hall resistance along the
transition line. In addition, a formula is suggested as a fit for isotherms
($\rho_{xx}$ vs. $\nu$) in the moderately high field regime, which exhibits a
violation of duality symmetry as the critical resistivity is evelated from the
`universal' value $h/e^2$.

</DOC>
<DOC>
<DOCNO> 152469 </DOCNO>
Path Integral Quantization of Dual Abelian Gauge Theory


  The path integral for 3+1 abelian gauge theory is rewritten in terms of a
real antisymmetric field allowing a dual action that couples the electric and
magnetic currents to the photon and each other in a gauge invariant manner.
Standard perturbative abelian quantum electrodynamics reemerges when the
monopole current vanishes. For certain simple relationships between the
monopole current and the electric current, the altered photon propagator can
exhibit abelian charge confinement or develop mass, modeling effects believed
to be present in non-abelian theories.

</DOC>
<DOC>
<DOCNO> 8525 </DOCNO>
Effect of the Orbital Level Difference in Doped Spin-1 Chains


  Doping of a two-orbital chain with mobile S=1/2 Fermions and strong Hund's
rule couplings stabilizing the S=1 spins strongly depends on the presence of a
level difference among these orbitals. By DMRG methods we find a finite spin
gap upon doping and dominant pairing correlations without level-difference,
whereas the presence of a level difference leads to dominant charge density
wave (CDW) correlations with gapless spin-excitations. The string correlation
function also shows qualitative differences between the two models.

</DOC>
<DOC>
<DOCNO> 84589 </DOCNO>
Einstein--Proca model: spherically symmetric solutions


  The Proca wave equation describes a classical massive spin 1 particle. We
analyze the gravitational interaction of this vector field. In particular, the
spherically symmetric solutions of the Einstein-Proca coupled system are
obtained numerically. Although at infinity the metric field approaches the
usual Schwarzschild (Reissner-Nordstr\"om) limit, we demonstrate the absence of
black hole type configurations.

</DOC>
<DOC>
<DOCNO> 83384 </DOCNO>
Contextual Inference in Computational Semantics


  In this paper, an application of automated theorem proving techniques to
computational semantics is considered. In order to compute the presuppositions
of a natural language discourse, several inference tasks arise. Instead of
treating these inferences independently of each other, we show how integrating
techniques from formal approaches to context into deduction can help to compute
presuppositions more efficiently. Contexts are represented as Discourse
Representation Structures and the way they are nested is made explicit. In
addition, a tableau calculus is present which keeps track of contextual
information, and thereby allows to avoid carrying out redundant inference steps
as it happens in approaches that neglect explicit nesting of contexts.

</DOC>
<DOC>
<DOCNO> 152014 </DOCNO>
Massive Superparticle with Tensorial Central Charges


  We construct the manifestly Lorenz-invariant formulation of the N=1 D=4
massive superparticle with tensorial central charges. The model contains a real
parameter k and at $k\ne 0$ possesses one $\kappa$-symmetry while at k=0 the
number of $\kappa$-symmetry is two. The equivalence of the formulations at all
$k\ne 0$ is obtained. The local transformations of $\kappa$-symmetry are
written out. It is considered the using of index spinor for construction of the
tensorial central charges. It is obtained the equivalence at classical level
between the massive D=4 superparticle with one $\kappa$-symmetry and the
massive D=4 spinning particle

</DOC>
<DOC>
<DOCNO> 169649 </DOCNO>
The class of languages recognizable by 1-way quantum finite automata is


  In this paper we develop little further the theory of quantum finite automata
(QFA). There are already few properties of QFA known, that deterministic and
probabilistic finite automata do not have e.g. they cannot recognize all
regular languages. In this paper we show, that class of languages recognizable
by QFA is not closed under union, even not under any Boolean operation, where
both arguments are significant.

</DOC>
<DOC>
<DOCNO> 116848 </DOCNO>
Lifetime Testing 700 MHz RF Windows for the Accelerator Production of


  Radio frequency (RF) windows are historically a point where failure occurs in
input-power couplers for accelerators. To understand more about the reliability
of high power RF windows, lifetime testing was done on 700 MHz coaxial RF
windows for the Low Energy Demonstration Accelerator (LEDA) project of the
Accelerator Production of Tritium (APT) program. The RF windows, made by
Marconi Applied Technologies (formerly EEV), were tested at 800 kW for an
extended period of time. Changes in the reflected power, vacuum, air outlet
temperature, and surface temperature were monitored over time. The results of
the life testing are summarized.

</DOC>
<DOC>
<DOCNO> 120383 </DOCNO>
A Dwarf Galaxy Survey in the Local Volume


  We are carrying out a comprehensive multi-wavelength study of dwarf galaxies
in the Local Volume (< 5 Mpc). After our all-sky survey more than doubled the
dwarf census we are now measuring structural parameters, integrated properties,
and velocities. Our 200-orbit HST snapshot program yields stellar content, star
formation history, and TRGB distances. We can thus study the morphology-density
relation in galaxy groups in three dimensions, the influence of environment on
galaxy evolution, and the universality of the metallicity-surface
brightness-luminosity relation.

</DOC>
<DOC>
<DOCNO> 67824 </DOCNO>
Trends in Grand Unification: unification at strong coupling and


  We review several problems of conventional Grand Unification and some new
approaches. In particular, we discuss strongly coupled Grand Unified Theories.
Standard Model may emerge as a low energy effective theory of composite
particles in these models. We construct a realistic model of this kind.

</DOC>
<DOC>
<DOCNO> 118814 </DOCNO>
The Age-Redshift Relation for Standard Cosmology


  We present compact, analytic expressions for the age-redshift relation
$\tau(z)$ for standard Friedmann-Lema\^ \itre-Robertson-Walker (FLRW)
cosmology. The new expressions are given in terms of incomplete Legendre
elliptic integrals and evaluate much faster than by direct numerical
integration.

</DOC>
<DOC>
<DOCNO> 72188 </DOCNO>
Electroweak symmetry breaking and extra dimensions


  The electroweak symmetry may be broken by a composite Higgs which arises
naturally as a bound state of the top quark if the standard model gauge fields
and fermions propagate in extra dimenions. The top quark mass and the Higgs
mass can be predicted from the infrared fixed points of the renormalization
group equations. The top quark mass is in good agreement with the experimental
value, and the Higgs boson mass is predicted to be $\sim 200$ GeV. The bounds
on the compactification scale can be quite low if all standard model fields
propagate in the same extra dimensions due to the momentum conservation in
extra dimensions. The current lower limits are about 300 GeV for one extra
dimension and 400-800 GeV for two extra dimensions. The future collider
experiments may either discover the Kaluza-Klein (KK) states of the standard
model fields or raise their mass limits significantly. There may also be some
other light bound states which could be observed at upcoming collider
experiments.

</DOC>
<DOC>
<DOCNO> 102740 </DOCNO>
On the Ground State of Ferromagnetic Hamiltonians


  It is generally believed that the ground state of the ferromagnetic
Heisenberg-Dirac-Van Vleck Hamiltonians acting on s=1/2 spins of a lattice with
N sites has the maximal possible value of the total spin S=N/2 and is N+1 times
degenerate. We present a rigorous proof of this statement, independent of the
lattice dimension and topology.

</DOC>
<DOC>
<DOCNO> 122726 </DOCNO>
Steps to the Planck Function : A Centenary Reflection


  The year 2000 marks the centenary of the Planck function for the blackbody
spectral distribution. Here are traced the steps, over 100 years, along the
path leading to this important formula.

</DOC>
<DOC>
<DOCNO> 12281 </DOCNO>
Density-correlator signatures of the vulcanization transition


  Certain density correlators, measurable via various experimental techniques,
are studied in the context of the vulcanization transition. It is shown that
these correlators contain essential information about both the vulcanization
transition and the emergent amorphous solid state. Contact is made with various
physical ingredients that have featured in experimental studies of amorphous
colloidal and gel systems and in theoretical studies of the glassy state.

</DOC>
<DOC>
<DOCNO> 69824 </DOCNO>
E_6 unification model building II. Clebsch-Gordan coefficients of


  We have computed the Clebsch-Gordan coefficients for the product (000001)
$\otimes$ (000001), where (000001) is the adjoint 78-dimensional representation
of $E_6$. The results are presented for the dominant weights of the irreducible
representations in this product. As a simple application we express the singlet
operator in $ 27 \otimes 78 \otimes \bar{27}$ in terms of multiplets of the
Standard Model gauge group.

</DOC>
<DOC>
<DOCNO> 69967 </DOCNO>
Domain Walls in SU(5)


  We consider the Grand Unified SU(5) model with a small or vanishing cubic
term in the adjoint scalar field in the potential. This gives the model an
approximate or exact Z$_2$ symmetry whose breaking leads to domain walls. The
simplest domain wall has the structure of a kink across which the Higgs field
changes sign ($\Phi \to -\Phi$) and inside which the full SU(5) is restored.
The kink is shown to be perturbatively unstable for all parameters. We then
construct a domain wall solution that is lighter than the kink and show it to
be perturbatively stable for a range of parameters. The symmetry in the core of
this domain wall is smaller than that outside. The interactions of the domain
wall with magnetic monopole is discussed and it is shown that magnetic
monopoles with certain internal space orientations relative to the wall pass
through the domain wall. Magnetic monopoles in other relative internal space
orientations are likely to be swept away on collision with the domain walls,
suggesting a scenario where the domain walls might act like optical
polarization filters, allowing certain monopole ``polarizations'' to pass
through but not others. As SU(5) domain walls will also be formed at small
values of the cubic coupling, this leads to a very complicated picture of the
evolution of defects after the Grand Unified phase transition.

</DOC>
<DOC>
<DOCNO> 9196 </DOCNO>
Nonlinear electron transport in normally pinched-off quantum wire


  Nonlinear electron transport in normally pinched-off quantum wires was
studied. The wires were fabricated from AlGaAs/GaAs heterostructures with
high-mobility two-dimensional electron gas by electron beam lithography and
following wet etching. At certain critical source-drain voltage the samples
exhibited a step rise of the conductance. The differential conductance of the
open wires was noticeably lower than e^2/h as far as only part of the
source-drain voltage dropped between source contact and saddle-point of the
potential relief along the wire. The latter limited the electron flow injected
to the wire. At high enough source-drain voltages the decrease of the
differential conductance due to the real space transfer of electrons from the
wire in GaAs to the doped AlGaAs layer was found. In this regime the sign of
differential magnetoconductance was changed with reversing the direction of the
current in the wire or the magnetic field, whet the magnetic field lies in the
heterostructure plane and is directed perpendicular to the current. The
dependence of the differential conductance on the magnetic field and its
direction indicated that the real space transfer events were mainly mediated by
the interface scattering.

</DOC>
<DOC>
<DOCNO> 84121 </DOCNO>
Quantum Evolution of the Bianchi Type I Model


  The behaviour of the flat anisotropic model of the Universe with a scalar
field is explored within the framework of quantum cosmology. The principal
moment of the account of an anisotropy is the presence either negative
potential barrier or positive repelling wall. In the first case occur the above
barrier reflection of the wave function of the Universe, in the second one
there is bounce off a potential wall. The further evolution of the Universe
represents an exponential inflating with fast losses of an anisotropy and
approach to the standard cosmological scenario.

</DOC>
<DOC>
<DOCNO> 102180 </DOCNO>
The Rotation Class of a Flow


  Generalizing a construction of A. Weil, we introduce a topological invariant
for flows on compact, connected, finite dimensional, abelian, topological
groups. We calculate this invariant for some examples and compare the invariant
with other flow invariants.

</DOC>
<DOC>
<DOCNO> 100532 </DOCNO>
Banach embedding properties of non-commutative L^p-spaces


  Let N and M be von Neumann algebras. It is proved that L^p(N) does not Banach
embed in L^p(M) for N infinite, M finite, 1 < or = p < 2. The following
considerably stronger result is obtained (which implies this, since the
Schatten p-class C_p embeds in L^p(N) for N infinite). Theorem: Let 1 < or = p
< 2 and let X be a Banach space with a spanning set (x_{ij}) so that for some C
< or = 1: (i) any row or column is C-equivalent to the usual ell^2-basis; (ii)
(x_{i_k,j_k}) is C-equivalent to the usual ell^p-basis, for any i_1 < i_2 < ...
and j_1 < j_2 < ... . Then X is not isomorphic to a subspace of L^p(M), for M
finite. Complements on the Banach space structure of non-commutative L^p-spaces
are obtained, such as the p-Banach-Saks property and characterizations of
subspaces of L^p(M) containing ell^p isomorphically. The spaces L^p(N) are
classified up to Banach isomorphism, for N infinite-dimensional, hyperfinite
and semifinite, 1 < or = p< infty, p not= 2. It is proved that there are
exactly thirteen isomorphism types; the corresponding embedding properties are
determined for p < 2 via an eight level Hasse diagram. It is also proved for
all 1 < or = p < infty that L^p(N) is completely isomorphic to L^p(M) if N and
M are the algebras associated to free groups, or if N and M are injective
factors of type III_lambda and III_{lambda'} for 0 < lambda, lambda' < or = 1.

</DOC>
<DOC>
<DOCNO> 151496 </DOCNO>
Nielsen-Olesen Vortices in Noncommutative Abelian Higgs Model


  We construct Nielsen-Olesen vortex solution in the noncommutative abelian
Higgs model. We derive the quantized topological flux of the vortex solution.
We find that the flux is integral by explicit computation in the large $\theta$
limit as well as in the small $\theta$ limit. In the context of a tachyon
vortex on the brane-antibrane system we demonstrate that it is this topological
charge that gives rise to the RR charge of the resulting BPS D-brane. We also
consider the left-right-symmetric gauge theory which does not have a
commutative limit and construct an exact vortex solution in it.

</DOC>
<DOC>
<DOCNO> 121099 </DOCNO>
Density, Velocity, and Magnetic Field Structure in Turbulent Molecular


  We use 3D numerical MHD simulations to follow the evolution of cold,
turbulent, gaseous systems with parameters representing GMC conditions. We
study three cloud simulations with varying mean magnetic fields, but identical
initial velocity fields. We show that turbulent energy is reduced by a factor
two after 0.4-0.8 flow crossing times (2-4 Myr), and that the magnetically
supercritical cloud models collapse after ~6 Myr, while the subcritical cloud
does not collapse. We compare density, velocity, and magnetic field structure
in three sets of snapshots with matched Mach numbers. The volume and column
densities are both log-normally distributed, with mean volume density a factor
3-6 times the unperturbed value, but mean column density only a factor 1.1-1.4
times the unperturbed value. We use a binning algorithm to investigate the
dependence of kinetic quantities on spatial scale for regions of column density
contrast (ROCs). The average velocity dispersion for the ROCs is only weakly
correlated with scale, similar to the mean size-linewidth relation for clumps
within GMCs. ROCs are often superpositions of spatially unconnected regions
that cannot easily be separated using velocity information; the same difficulty
may affect observed GMC clumps. We analyze magnetic field structure, and show
that in the high density regime, total magnetic field strengths increase with
density with logarithmic slope 1/3 -2/3. Mean line-of-sight magnetic field
strengths vary widely across a projected cloud, and do not correlate with
column density. We compute simulated interstellar polarization maps at varying
orientations, and determine that the Chandrasekhar-Fermi formula multiplied by
a factor ~0.5 yields a good estimate of the plane-of sky magnetic field
strength provided the dispersion in polarization angles is < 25 degrees.

</DOC>
<DOC>
<DOCNO> 84902 </DOCNO>
Localization of Gravity on Dilatonic Domain Walls: Addendum to


  We supplement the discussion on localization of gravity on dilatonic domain
walls in ``Solitons in Brane Worlds'' (Nucl. Phys. B576, 106, hep-th/9911218)
by giving unified and coherent discussion which combines the result of this
paper and the expanded results in the author's subsequent papers in an attempt
to avoid misleading readers. We also discuss the possible string theory
embeddings of the Randall-Sundrum type brane world scenarios through
non-dilatonic and dilatonic domain walls, which straightforwardly follows from
the author's previous works but was not elaborated explicitly.

</DOC>
<DOC>
<DOCNO> 116866 </DOCNO>
New Developments in Linear Colliders Final Focus Systems


  The length, complexity and cost of the present Final Focus designs for linear
colliders grows very quickly with the beam energy. In the paper, a novel final
focus system is presented and compared with the one proposed for NLC. This new
design is simpler, shorter and cheaper, with comparable bandwidth, tolerances
and tunability. Moreover, the length scales slower than linearly with energy
allowing for a more flexible design which is applicable over a much larger
energy range.

</DOC>
<DOC>
<DOCNO> 12422 </DOCNO>
Equivalence of two approaches for the inhomogeneous density in the


  In this article we show that the inhomogeneous density obtained from a
density-functional theory of classical fluids in the canonical ensemble (CE),
recently presented by White et al [Phys. Rev. Lett. 84 (2000) 1220], is
equivalent to first order to the result of the series expansion of the CE
inhomogeneous density introduced by Gonzalez et al [Phys. Rev. Lett. 79 (1997)
2466].

</DOC>
<DOC>
<DOCNO> 10812 </DOCNO>
Spontaneous plaquette formation in the SU(4) Spin-Orbital ladder


  The low-energy properties of the SU(4) spin-orbital model on a two-leg ladder
are studied by a variety of analytical and numerical techniques. Like in the
case of SU(2) models, there is a singlet-multiplet gap in the spectrum, but the
ground-state is two-fold degenerate. An interpretation in terms of
SU(4)-singlet plaquettes is proposed. The implications for general
two-dimensional lattices are outlined.

</DOC>
<DOC>
<DOCNO> 39984 </DOCNO>
Discovering mirror particles at the Large Hadron Collider and the


  The Mirror Matter or Exact Parity Model sees every standard particle,
including the physical neutral Higgs boson, paired with a parity partner. The
unbroken parity symmetry forces the mass eigenstate Higgs bosons to be maximal
mixtures of the ordinary and mirror Higgs bosons. Each of these mass
eigenstates will therefore decay 50% of the time into invisible mirror
particles, providing a clear and interesting signature for the Large Hadron
Collider (LHC) which could thus establish the existence of the mirror world.
However, for this effect to be observable the mass difference between the two
eigenstates must be sufficiently large. In this paper, we study cosmological
constraints from Big Bang Nucleosynthesis on the mass difference parameter. We
find that the temperature of the radiation dominated (RD) phase of the universe
should never have exceeded a few 10's of GeV if the mass difference is to be
observable at the LHC. Chaotic inflation with very inefficient reheating
provides an example of how such a cosmology could arise. We conclude that the
LHC could thus discover the mirror world and simultaneously establish an upper
bound on the temperature of the RD phase of the universe.

</DOC>
<DOC>
<DOCNO> 100208 </DOCNO>
The dimensions of Hausdorff and Mendes France. A comparative study


  This paper contains a comparative study of two families of simple curves
drawn in the plane. On the one hand, we have the fractal curves on the unit
interval, with self-similar structure, which have associated a Hausdorff
dimension. On the other hand, we have the opposite: a class of locally
rectifiable unbounded curves, which have another "fractional dimension" defined
by M. Mendes France. We propose a geometrical constructive process that will
allow us to obtain - as the limit of a sequence of polygonal curves - one curve
of the first family, by contractive transformations; and another of the second
family, by expansive transformations. Thanks to this process of linking curves
from both families, we are able to compare their dimensions - our aim in this
work -, and to obtain interesting results such as the equality of the latter in
the case of strict self-similarity.

</DOC>
<DOC>
<DOCNO> 99743 </DOCNO>
Limit distributions of expanding translates of certain orbits on


  Let L be a Lie group and Lambda a lattice in L. Suppose G is a non-compact
simple Lie group realized as a Lie subgroup of L, and the image of G on
L/Lambda is dense. Let c be a diagonalizable element of G not contained in a
compact subgroup. Let U be the expanding horospherical subgroup of G associated
to c. Let Omega be a nonempty open subset of U, and {n_i} be a sequence of
natural numbers tending to infinity. It is shown that the image of the union of
the sets c^{n_i}.Omega in L/Lambda is dense. A stronger measure theoretic
formulation of this result is also obtained. Among other applications of the
above result, we describe G-equivariant topological factors of the product
space L/Lambda \times G/P, where the real rank of G is greater than 1, P is a
parabolic subgroup of G, and G acts diagonally. We also describe equivariant
topological factors of unipotent flows on finite volume homogeneous spaces of
Lie groups.

</DOC>
<DOC>
<DOCNO> 80642 </DOCNO>
The construction of generalized Dirac operators on the lattice


  We discuss the steps to construct Dirac operators which have arbitrary
fermion offsets, gauge paths, a general structure in Dirac space and satisfy
the basic symmetries (gauge symmetry, hermiticity condition, charge
conjugation, hypercubic rotations and reflections) on the lattice. We give an
extensive set of examples and offer help to add further structures.

</DOC>
<DOC>
<DOCNO> 118347 </DOCNO>
Mining for Metals in the Lyman Alpha Forest


  In order to ascertain the extent of metal enrichment in the Ly alpha forest,
we have analysed a very high S/N spectrum of the z = 3.625 QSO Q1422+231. We
find that in high column density Ly alpha clouds, the power law column density
distribution function of C IV continues down to log N(C IV) = 11.7. In
addition, by analysing pixel-by-pixel optical depths we show that there are
considerably more metals in the Ly alpha forest than are currently directly
detectable.

</DOC>
<DOC>
<DOCNO> 70974 </DOCNO>
Physics from Bose-Einstein correlations in high energy multiparticle


  Bose-Einstein correlations are being exploited to obtain information about
the structure of the sources of hadrons in multiple particle production
processes. In this paper the principles of this approach are described and some
of the controversies about their implementation are discussed.

</DOC>
<DOC>
<DOCNO> 120714 </DOCNO>
Polytropes: Implications for Molecular Clouds and Dark Matter


  Polytropic models are reasonably successful in acounting for the observed
features of molecular clouds. Multi-pressure polytropes include the various
pressure components that are important in molecular clouds, whereas composite
polytropes provide a representation for the core halo structure.
  Small, very dense (n~10^{11} cm^{-3}) molecular clouds have been proposed as
models for both dark matter and for extreme scattering events. Insofar as the
equation of state in these clouds can be represented by a single polytropic
relation (pressure varies as a power of the density), such models conflict with
observation. It is possible to contrive composite polytropes that do not
conflict with observation, but whether the thermal properties of the clouds are
consistent with such structure remains to be determined.

</DOC>
<DOC>
<DOCNO> 117410 </DOCNO>
Fluorescent Excitation of Spectral Lines in Planetary Nebulae


  Fluorescent excitation of spectral lines is demonstrated as a function of
temperature-luminosity and the distance of the emitting region from the central
stars of planetary nebulae. The electron densities and temperatures are
determined, and the method is exemplified through a detailed analysis of
spectral observations of a high excitation PN, NGC 6741, observed by Hyung and
Aller(1997). Fluorescence should also be important in the determination of
element abundances. It is suggested that the method could be generally applied
to determine or constrain the luminosity and the region of spectral emission in
other intensively radiative sources such as novae, supernovae, and active
galactic nuclei.

</DOC>
<DOC>
<DOCNO> 84854 </DOCNO>
Lectures on the Microscopic Modeling of the 5-dim. Black Hole of IIB


  In these notes we review the theory of the microscopic modeling of the 5-dim.
black hole of type IIB string theory in terms of the $D1-D5$ brane system. The
emphasis here is more on the brane dynamics rather than on supergravity
solutions. We present a discussion of the low energy brane dynamics and account
for black hole thermodynamics and Hawking radiation rates. These considerations
are valid in the regime of supergravity due to the non-renormalization of the
low energy dynamics in this model.

</DOC>
<DOC>
<DOCNO> 11444 </DOCNO>
Minimum Entropy Aproach to Word Segmentation Problems


  Given a sequence composed of a limit number of characters, we try to "read"
it as a "text". This involves to segment the sequence into "words". The
difficulty is to distinguish good segmentation from enormous number of random
ones.Aiming at revealing the nonrandomness of the sequence as strongly as
possible, by applying maximum likelihood method, we find a quantity called
Segmentation Entropy that can be used to fulfill the duty. Contrary to
commonplace where maximum entropy principle was applied to obtain good
solution, we choose to {\em minimize} the segmentation entropy to obtain good
segmentation. The concept developed in this letter can be used to study the
noncoding DNA sequences, e.g., for regulatory elements prediction, in eukaryote
genomes.

</DOC>
<DOC>
<DOCNO> 71554 </DOCNO>
Anisotropy dissipation in brane-world inflation


  We examine the behavior of an anisotropic brane-world in the presence of
inflationary scalar fields. We show that, contrary to naive expectations, a
large anisotropy does not adversely affect inflation. On the contrary, a large
initial anisotropy introduces more damping into the scalar field equation of
motion, resulting in greater inflation. The rapid decay of anisotropy in the
brane-world significantly increases the class of initial conditions from which
the observed universe could have originated. This generalizes a similar result
in general relativity. A unique feature of Bianchi I brane-world cosmology
appears to be that for scalar fields with a large kinetic term the initial
expansion of the universe is quasi-isotropic. The universe grows more
anisotropic during an intermediate transient regime until anisotropy finally
disappears during inflationary expansion.

</DOC>
<DOC>
<DOCNO> 170314 </DOCNO>
Correlated Errors in Quantum Error Corrections


  We show that errors are not generated correlatedly provided that quantum bits
do not directly interact with (or couple to) each other. Generally, this
no-qubits-interaction condition is assumed except for the case where two-qubit
gate operation is being performed. In particular, the no-qubits-interaction
condition is satisfied in the collective decoherence models. Thus, errors are
not correlated in the collective decoherence. Consequently, we can say that
current quantum error correcting codes which correct single-qubit-errors will
work in most cases including the collective decoherence.

</DOC>
<DOC>
<DOCNO> 69992 </DOCNO>
Finite pion width effects on the rho--meson


  We study the influence of the finite damping width of pions on the in-medium
properties of the rho-meson in an interacting meson gas model at finite
temperature. Using vector dominance also implications on the resulting dilepton
spectra from the decay of the rho-meson are presented. A set of coupled Dyson
equations with self energies up to the sunset diagram level is solved self
consistently. Following a Phi-derivable scheme the self energies are
dynamically determined by the self consistent propagators. Some problems
concerning the self consistent treatment of vector or gauge bosons on the
propagator level, in particular, if coupled to currents arising from particles
with a sizable damping width, are discussed.

</DOC>
<DOC>
<DOCNO> 83321 </DOCNO>
Language identification of controlled systems: Modelling, control and


  Formal language techniques have been used in the past to study autonomous
dynamical systems. However, for controlled systems, new features are needed to
distinguish between information generated by the system and input control. We
show how the modelling framework for controlled dynamical systems leads
naturally to a formulation in terms of context-dependent grammars. A learning
algorithm is proposed for on-line generation of the grammar productions, this
formulation being then used for modelling, control and anomaly detection.
Practical applications are described for electromechanical drives. Grammatical
interpolation techniques yield accurate results and the pattern detection
capabilities of the language-based formulation makes it a promising technique
for the early detection of anomalies or faulty behaviour.

</DOC>
<DOC>
<DOCNO> 11069 </DOCNO>
Resistivity of Mixed-Phase Manganites


  The resistivity $\rho_{dc}$ of manganites is studied using a
random-resistor-network, based on phase-separation between metallic and
insulating domains. When percolation occurs, both as chemical composition and
temperature vary, results in good agreement with experiments are obtained.
Similar conclusions are reached using quantum calculations and microscopic
considerations. Above the Curie temperature, it is argued that ferromagnetic
clusters should exist in Mn-oxides. Small magnetic fields induce large
$\rho_{dc}$ changes and a bad-metal state with (disconnected) insulating
domains.

</DOC>
<DOC>
<DOCNO> 39645 </DOCNO>
Leading Particle Production in Light Flavour Jets


  The energy distribution and type of the particle with the highest momentum in
quark jets are determined for each of the five quark flavours making only
minimal model assumptions. The analysis is based on a large statistics sample
of hadronic Z0 decays collected with the OPAL detector at the LEP e+e-
collider. These results provide a basis for future studies of light flavour
production at other centre-of-mass energies. We use our results to study the
hadronisation mechanism in light flavour jets and compare the data to the QCD
models JETSET and HERWIG. Within the JETSET model we also directly determine
the suppression of strange quarks to be gamma_s=0.422+-0.049 (stat.)+-0.059
(syst.) by comparing the production of charged and neutral kaons in strange and
non-strange light quark events. Finally we study the features of baryon
production.

</DOC>
<DOC>
<DOCNO> 10160 </DOCNO>
Conversion of free magnetic polaron into vortex lattice in diluted


  We show that in strong (quantizing) magnetic fields "ordinary" free magnetic
polaron in diluted magnetic semiconductors (of type $A^2MeB^6$, where
Me=Fe, Mn) exists in the form of vortex lattice quite similar to that
in type II superconductors (Abricosov vortex lattice). The region of external
parameters (like external magnetic field and temperature), where such lattice
exists, is determined from the condition that lattice dimension is less or
equal to polaron localization radius.

</DOC>
<DOC>
<DOCNO> 119477 </DOCNO>
Presupernova Evolution of Rotating Massive Stars II: -- Evolution of the


  We investigate the evolution of the surface properties of models for rotating
massive stars, i.e., their luminosities, effective temperatures, surface
rotational velocities, and surface abundances of all isotopes, from the zero
age main sequence to the supernova stage. Our results are based on the grid of
stellar models by Heger, Langer, & Woosley, which covers solar metallicity
stars in the initial mass range 8 - 25 solar masses. Results are parameterized
by initial mass, initial rotational velocity and major uncertainties in the
treatment of the rotational mixing inside massive stars.
  Rotationally induced mixing processes widen the main sequence and increase
the core hydrogen burning lifetime, similar to the effects of convective
overshooting. It can also significantly increase the luminosity during and
after core hydrogen burning, and strongly affects the evolution of the
effective temperature. Our models predict surface rotational velocities for
various evolutionary stages, in particular for blue supergiants, red
supergiants, and for the immediate presupernova stage.
  We discuss the changes of the surface abundances due to rotationally induced
mixing for main sequence and post main sequence stars. We single out two
characteristics by which the effect of rotational mixing can be distinguished
from that of massive close binary mass transfer, the only alternative process
leading to non-standard chemical surface abundances in massive stars. A
comparison with observed abundance anomalies in various types of massive stars
supports the concept of rotational mixing in massive stars and indicates that
it is responsible for most of the observed abundance anomalies.

</DOC>
<DOC>
<DOCNO> 119137 </DOCNO>
The KPNO International Spectroscopic Survey. I. Description of the


  The KPNO International Spectroscopic Survey (KISS) is a new objective-prism
survey for extragalactic emission-line objects. It combines many of the
features of previous slitless spectroscopic surveys that were carried out with
Schmidt telescopes using photographic plates with the advantages of modern CCD
detectors. It is the first purely digital objective-prism survey, and extends
previous photographic surveys to substantially fainter flux limits. In this,
the first paper in the series, we give an overview of the survey technique,
describe our data processing procedures, and present examples of the types of
objects found by KISS. Our first H-alpha-selected survey list detects objects
at the rate of 18.1 per square degree, which is 181 times higher than the
surface density of the Markarian survey.Since the sample is line-selected,
there is an imposed redshift limit of z ~ 0.095 due to the filter employed for
the objective-prism observations. We evaluate the quality of the observed
parameters derived from the survey data, which include accurate astrometry,
photometry, redshifts, and line fluxes. Finally, we describe some of the many
applications the KISS database will have for addressing specific questions in
extragalactic astronomy. Subsequent papers in this series will present our
survey lists of emission-line galaxy candidates.

</DOC>
<DOC>
<DOCNO> 39950 </DOCNO>
Search for Manifestations of New Physics in Fermion-Pair Production at


  The measurements of hadron and lepton-pair production cross sections and
leptonic forward-backward asymmetries performed with the L3 detector at
centre-of-mass energies between 130 GeV and 189 GeV are used to search for new
physics phenomena such as: contact interactions, exchange of virtual
leptoquarks, scalar quarks and scalar neutrinos, effects of TeV strings in
models of quantum gravity with large extra dimensions and non-zero sizes of the
fermions. No evidence for these phenomena is found and new limits on their
parameters are set.

</DOC>
<DOC>
<DOCNO> 119582 </DOCNO>
A method of self-consistent three-dimensional solution of the


  A technique is proposed for constructing three-dimensional solutions
comlplying with the self-consistent magnetohydrostatic (MHS) equations and with
observations along the line of sight of the magnetic field at the photosphere.
The technique is a generalization of a paper Rudenko, {\tt
arXiv:astro-ph/0004222} to a potential-field approximation. The solution of the
problem under consideration leans a representation of the magnetic field in
terms of a scalar function, with its subsequent harmonic expansion in terms of
a spherical functional basis that satisfies specified boundary conditions. A
numerical realization of the proposed method is expected to permit a real-time
modelling of three-dimensional magnetic field, temperature, pressure and
density distributions.

</DOC>
<DOC>
<DOCNO> 69131 </DOCNO>
MSSM Higgs Sector at the One-Loop Level


  This work provides an elementary introduction to the Higgs sector
renormalisation within the Minimal Suppersymmetric Standard Model (MSSM)
framework. The MSSM tree-level relation $m_h^2+m_H^2=m_A^2+m_Z^2$ is
renormalised using the standard technique of direct computation of the relevant
one-loop Feynman diagrams. The expected cancellation of ultraviolet divergences
is explicitly checked and the well-known leading-log term is recovered.

</DOC>
<DOC>
<DOCNO> 151827 </DOCNO>
Brane-world Kaluza-Klein reductions and Branes on the Brane


  We present a systematic study of a new type of consistent ``Brane-world
Kaluza-Klein Reduction,'' which describe fully non-linear deformations of
co-dimension one objects that arise as solutions of a large class of gauged
supergravity theories in diverse dimensions, and whose world-volume theories
are described by ungauged supergravities with one half of the original
supersymmetry. In addition, we provide oxidations of these Ansatze which are in
general related to sphere compactified higher dimensional string theory or
M-theory. Within each class we also provide explicit solutions of brane
configurations localised on the world-brane. We show that at the Cauchy horizon
(in the transverse dimension of the consistently Kaluza-Klein reduced
world-brane) there is a curvature singularity for any configuration with a
non-null Riemann curvature or a non-vanishing Ricci scalar that lives in the
world-brane. Since the massive Kaluza-Klein modes can be consistently
decoupled, they cannot participate in regulating these singularities.

</DOC>
<DOC>
<DOCNO> 40577 </DOCNO>
B decays to Ds^(*) and D^*


  The e+e- annihilation data recorded with the BABAR detector has been used to
study B^0 decays to Ds^(*)+ and D^*-$ mesons. The production fraction of
inclusive Ds^(*)+ and the corresponding momentum spectra have been determined.
Exclusive decays B^0 --> D^*- Ds^(*)+ have been identified with a partial
reconstruction technique and their branching ratios have been measured. Fully
reconstructed B^0 decays in the hadronic modes B^0 --> D^*- pi+ andB^0 --> D^*-
rho+ have been also studied and the measurement of their absolute branching
fractions is reported.

</DOC>
<DOC>
<DOCNO> 8400 </DOCNO>
Two time scales and FDT violation in a Finite Dimensional Model for


  We study the breakdown of fluctuation-dissipation relations between time
dependent density-density correlations and associated responses following a
quench in chemical potential in the Frustrated Ising Lattice Gas. The
corresponding slow dynamics is characterized by two well separated time scales
which are characterized by a constant value of the fluctuation-dissipation
ratio. This result is particularly relevant taking into account that activated
processes dominate the long time dynamics of the system.

</DOC>
<DOC>
<DOCNO> 13218 </DOCNO>
The Effect of Surface Roughness on the Universal Thermal Conductance


  We explain the reduction of the thermal conductance below the predicted
universal value observed by Schwab et al. in terms of the scattering of thermal
phonons off surface roughness using a scalar model for the elastic waves. Our
analysis shows that the thermal conductance depends on two roughness
parameters: the roughness amplitude $\delta $ and the correlation length $a$.
At sufficiently low temperatures the conductance decrease from the universal
value quadratically with temperature at a rate proportional to $\delta ^{2}a$.
Values of $\delta$ equal to 0.22 and $a$ equal to about 0.75 of the width of
the conduction pathway give a good fit to the data.

</DOC>
<DOC>
<DOCNO> 10869 </DOCNO>
Magnetization plateaus of the Shastry-Sutherland model for


  We study the Heisenberg antiferromagnet on the Shastry-Sutherland lattice
under magnetic fields, to clarify the magnetic properties of SrCu_2(BO_3)_2.
Treating magnetic excitations promoted by the field as Bose particles and using
strong coupling expansion, we derive an effective Hamiltonian for the effective
magnetic particles. Anisotropic repulsive interactions between effective
particles induce `insulating' states with a stripe SDW structure at
magnetization m/m_{sat}=1/3 and a checkerboard structure at 1/2, and thereby
form magnetization plateaus. Supersolid phases appear around insulating SDW
phases by changing the magnetic field. Nature of these supersolid phases is
discussed in detail. We also demonstrate how the geometry of the
Shastry-Sutherland lattice affects dynamical properties of magnetic excitations
significantly and makes a novel type of quintuplet (S=2) boundstates condense
for very small magnetization.

</DOC>
<DOC>
<DOCNO> 102226 </DOCNO>
Higher Abel-Jacobi Maps


  This paper forms the major portion of a talk given at the International
Colloquium on Arithmetic, Algebra and Geometry at TIFR, Mumbai in Jan 2000. We
look at the problem of detecting cycles with trivial Abel-Jacobi invariant. M.
Green proposed a Hodge-theoretic method to which C. Voisin found a
counter-example. We present an easier example. We also propose another possible
invariant to detect these classes using Hodge Theory. Similar methods have been
proposed earlier by M. Asakura and M. Saito.

</DOC>
<DOC>
<DOCNO> 83481 </DOCNO>
A Complete Characterization of Complete Intersection-Type Theories


  We characterize those intersection-type theories which yield complete
intersection-type assignment systems for lambda-calculi, with respect to the
three canonical set-theoretical semantics for intersection-types: the inference
semantics, the simple semantics and the F-semantics. These semantics arise by
taking as interpretation of types subsets of applicative structures, as
interpretation of the intersection constructor set-theoretic inclusion, and by
taking the interpretation of the arrow constructor a' la Scott, with respect to
either any possible functionality set, or the largest one, or the least one.
  These results strengthen and generalize significantly all earlier results in
the literature, to our knowledge, in at least three respects. First of all the
inference semantics had not been considered before. Secondly, the
characterizations are all given just in terms of simple closure conditions on
the preorder relation on the types, rather than on the typing judgments
themselves. The task of checking the condition is made therefore considerably
more tractable. Lastly, we do not restrict attention just to lambda-models, but
to arbitrary applicative structures which admit an interpretation function.
Thus we allow also for the treatment of models of restricted lambda-calculi.
Nevertheless the characterizations we give can be tailored just to the case of
lambda-models.

</DOC>
<DOC>
<DOCNO> 7948 </DOCNO>
The magnetic neutron scattering resonance of high-T_c superconductors in


  The magnetic resonance at 41 meV observed in neutron scattering studies of Y
Ba_2 Cu_3 O_7 holds a key position in the understanding of high-T_c
superconductivity. Within the SO(5) model for superconductivity and
antiferromagnetism, we have calculated the effect of an applied magnetic field
on the neutron scattering cross-section of the magnetic resonance. In the
presence of vortices, the neutron scattering cross-section shows clear
signatures of not only the fluctuations in the superconducting order parameter
\psi, but also the modulation of the phase of \psi due to vortices. In
reciprocal space we find that i) the scattering amplitude is zero at
(pi/a,pi/a), ii) the resonance peak is split into a ring with radius pi/d
centered at (pi/a,pi/a), d being the vortex lattice constant, and consequently,
iii) the splitting pi/d scales with the magnetic field as sqrt{B}.

</DOC>
<DOC>
<DOCNO> 71487 </DOCNO>
CP Violation in B Decays


  The role of B decays in the study of CP violation is reviewed. We treat the
interactions and spectroscopy of the $b$ quark and then introduce CP violation
in $B$ meson decays, including time-dependences, decays to CP eigenstates and
non-eigenstates, and flavor tagging. Additional topics include studies of
strange $B$'s, decays to pairs of light pseudoscalar mesons, and the roles of
gluonic and electroweak penguin diagrams, and final-state interactions.

</DOC>
<DOC>
<DOCNO> 69509 </DOCNO>
The Lame equation in parametric resonance after inflation


  We show that the most general inflaton potential in Minkowski spacetime for
which the differential equation for the Fourier modes of the matter fields
reduces to Lam\'e's equation is of the form $V(\phi)=
\lambda\phi^4/4+K\phi^2/2+\mu/(2\phi^2)+V_0$. As an application, we study the
preheating phase after inflation for the above potential with K=0 and arbitrary
$\lambda,\mu>0$. For certain values of the coupling constant between the
inflaton and the matter fields, we calculate the instability intervals and the
characteristic exponents in closed form.

</DOC>
<DOC>
<DOCNO> 68836 </DOCNO>
Topological susceptibility in full QCD at zero and finite temperature


  We present a study of the topological susceptibility $\chi$ on the lattice
for full QCD with 2 and 4 flavours of staggered fermions at zero and finite
temperature T. We find that $\chi$ presents a sharp drop across the
deconfinement transition. We also study the dependence of $\chi$ on the quark
mass at T=0: we have no conclusive evidence for the expected chiral behaviour.

</DOC>
<DOC>
<DOCNO> 120453 </DOCNO>
Metal Abundances in the Magellanic Stream


  We report on the first metallicity determination for gas in the Magellanic
Stream, using archival HST GHRS data for the background targets Fairall 9, III
Zw 2, and NGC 7469. For Fairall 9, using two subsequent HST revisits and new
Parkes Multibeam Narrowband observations, we have unequivocally detected the
MSI HI component of the Stream (near its head) in SII1250,1253 yielding a
metallicity of [SII/H]=-0.55+/-0.06(r)+/-0.2(s), consistent with either an SMC
or LMC origin and with the earlier upper limit set by Lu et al. (1994). We also
detect the saturated SiII1260 line, but set only a lower limit of
[SiII/H]>-1.5. We present serendipitous detections of the Stream, seen in
MgII2796,2803 absorption with column densities of (0.5-1)x10^13 cm^-2 toward
the Seyfert galaxies III Zw 2 and NGC 7469. These latter sightlines probe gas
near the tip of the Stream (80 deg down-Stream of Fairall 9). For III Zw 2, the
lack of an accurate HI column density and the uncertain MgIII ionization
correction limits the degree to which we can constrain [Mg/H]; a lower limit of
[MgII/HI]>-1.3 was found. For NGC 7469, an accurate HI column density
determination exists, but the extant FOS spectrum limits the quality of the
MgII column density determination, and we conclude that [MgII/HI]>-1.5.
Ionization corrections associated with MgIII and HII suggest that the
corresponding [Mg/H] may range lower by 0.3-1.0 dex. However, an upward
revision of 0.5-1.0 dex would be expected under the assumption that the Stream
exhibits a dust depletion pattern similar to that seen in the Magellanic
Clouds. Remaining uncertainties do not allow us to differentiate between an LMC
versus SMC origin to the Stream gas.

</DOC>
<DOC>
<DOCNO> 13641 </DOCNO>
Ground State and Quasiparticle Spectrum of a Two Component Bose-Einstein


  We consider a dilute atomic Bose-Einstein condensate with two non-degenerate
internal energy levels. The presence of an external radiation field can result
in new ground states for the condensate which result from the lowering of the
condensate energy due to the interaction energy with the field. In this
approach there are no instabilities in the quasiparticle spectrum as was
previously found by Goldstein and Meystre (Phys. Rev. A \QTR{bf}{55}, 2935
(1997)).

</DOC>
<DOC>
<DOCNO> 11134 </DOCNO>
Entropy Burst from Parabolic Potentials


  The change of the energy of ground state is investigated in a thermodynamical
process by using the model described by one-dimensional harmonic oscillator +
two-dimensional isotropic parabolic potential barrier such as
$V(x,y,z)=m\omega^2 x^2/2 -m\gamma^2 (y^2+z^2)/2$. In the process where two
independent many-particle systems suddenly touch with each other, it is shown
that the lowest energy after the interaction can possibly be smaller than that
before the interaction and then the entropy burst can occur.

</DOC>
<DOC>
<DOCNO> 100006 </DOCNO>
The Verlinde formula for parabolic bundles


  The moduli space M(n,d) is an algebraic variety parametrizing those
representations of the fundamental group of a punctured Riemann surface into
the Lie group SU(n) for which a loop around the boundary is sent to the n-th
root of unity exp (2 \pi i d/n) multiplied by the identity matrix. If n and d
are coprime it is in fact a K\"ahler manifold. One may relax the constraint and
study moduli spaces M(L) parametrizing those representations for which the loop
around the boundary is sent to an element conjugate to L, if L is some element
in SU(n), and these are also K\"ahler manifolds for a suitable class of L.
  The Verlinde formula calculates the dimension of the space of holomorphic
sections of certain line bundles over the spaces M(n,d) and M(L). We recall how
a new proof of the Verlinde formula for M(n,d) given in joint work with Frances
Kirwan may be obtained, and show how to modify this proof to obtain a proof of
the variant of the Verlinde formula which applies to M(L) (the moduli space of
parabolic bundles with one marked point) and to the analogous object with b
marked points.

</DOC>
<DOC>
<DOCNO> 179046 </DOCNO>
Structure functions for the three nucleon system


  The spectral functions and light-cone momentum distributions of protons and
neutrons in 3He and 3H are given in terms of the three-nucleon wave function
for realistic nucleon-nucleon interactions. To reduce computational complexity,
separable expansions are employed for the nucleon-nucleon potentials. The
results for the light-cone momentum distributions suggest that they are not
very sensitive to the details of the two-body interaction, as long as it has
reasonable short-range repulsion. The unpolarised and polarised structure
functions are examined for both 3He and 3H in order to test the usefulness of
3He as a neutron target. It is found that the measurement of the spin structure
function of polarised 3H would provide a very clear test of the predicted
change in the polarised parton distributions of a bound proton.

</DOC>
<DOC>
<DOCNO> 152464 </DOCNO>
Low-energy electron-electron bound states in planar QED


  In this talk, we present a parity-preserving QED3 model with spontaneous
breaking of a local U(1)-symmetry. The breaking is accomplished by a potential
of the phi^6-type. It is shown that a net attractive interaction appears in the
Moeller scattering (s- and p-wave scatterings between two electrons) as
mediated by the gauge field and a Higgs scalar. We show, by solving numerically
the Schroedinger equation for both the scattering potentials (s- and p-wave),
that in the weak-coupling regime only s-wave bound states appear, whereas in
the strong-coupling regime s- and p-wave bound states show up. Also, we discuss
possible applications of the model to the phenomenology of high-Tc
superconductors and to the re-entrant superconductivity effect.

</DOC>
<DOC>
<DOCNO> 120422 </DOCNO>
Riemannian collineations in General Relativity and in Einstein-Cartan 


  Riemannian vectorial collineations along with current Killing conservation are shown to lead to tensorial collineations for the energy-stress tensor in general relativity and in Einstein-Cartan Weyssenhoff fluid cosmology.

</DOC>
<DOC>
<DOCNO> 119667 </DOCNO>
Disk mass accretion rate and infrared flares in GRS 1915+105


  We have analyzed in detail a set of Rossi X-ray Timing Explorer (RXTE)
observations of the galactic microquasar GRS 1915+105 corresponding to times
when quasi-periodic oscillations in the infrared have been reported. From
time-resolved spectral analysis, we have estimated the mass accretion rate
through the (variable) inner edge of the accretion disk. We compare this
accretion rate to an estimate of the mass/energy outflow rate in the jet. We
discuss the possible implications of these results in terms of disk-instability
and jet ejection, and in particular note an apparent anti-correlation between
the accretion and ejection rates, implying that the gas expelled in the jet
must leave the accretion disk before reaching its innermost radius.

</DOC>
<DOC>
<DOCNO> 102865 </DOCNO>
Induced representations of quantum kinematical algebras


  We construct the induced representations of the null-plane quantum Poincar\'e
and quantum kappa Galilei algebras in (1+1) dimensions. The induction procedure
makes use of the concept of module and is based on the existence of a pair of
Hopf algebras with a nondegenerate pairing and dual bases.

</DOC>
<DOC>
<DOCNO> 39683 </DOCNO>
Partonic structure of pi and rho mesons from data on hard


  We fitted the pi-pi mass distribution in the range 0.5 < mpipi < 1.1 GeV
measured in hard exclusive positron-proton reactions at HERA by the form
dictated by QCD at leading twist level. Extracted parameters are related to
valence quark distribution in the pion, and to the pion and rho meson
distribution amplitudes. We obtain, for the first time, a measurement of the
second Gegenbauer coefficient of the rho meson distribution amplitude:
$a_2^{(\rho)}= -0.10\pm 0.20 $ for a photon virtuality of <Q^2>=21.2 GeV^2.

</DOC>
<DOC>
<DOCNO> 119192 </DOCNO>
HI 21cm-line observations with the GMRT towards interstellar clouds


  We have made HI 21cm-line absorption measurements using the GMRT towards 15
directions in the Galaxy which are known to have high random velocity clouds as
seen in the optical absorption lines of CaII and NaI. For the first time, in 6
out of these 15 directions we detect HI absorption features corresponding to
the high random velocity optical absorption lines. The mean optical depth of
these detections is ~ 0.08.

</DOC>
<DOC>
<DOCNO> 7659 </DOCNO>
The effect of compression on the global optimization of atomic clusters


  Recently, Locatelli and Schoen proposed a transformation of the potential
energy that aids the global optimization of Lennard-Jones clusters with
non-icosahedral global minima. These cases are particularly difficult to
optimize because the potential energy surface has a double funnel topography
with the global minimum at the bottom of the narrower funnel. Here we analyse
the effect of this type of transformation on the topography of the potential
energy surface. The transformation, which physically corresponds to a
compression of the cluster, firstly reduces the number of stationary points on
the potential energy surface. Secondly, we show that for a 38-atom cluster with
a face-centred-cubic global minimum the transformation causes the potential
energy surface to become increasingly dominated by the funnel associated with
the global minimum. The transformation has been incorporated in the
basin-hopping algorithm using a two-phase approach.

</DOC>
<DOC>
<DOCNO> 70723 </DOCNO>
Radiative Correction to the Transferred Polarization in Elastic


  Model independent radiative correction to the recoil proton polarization for
the elastic electron-proton scattering is calculated within method of electron
structure functions. The explicit expressions for the recoil proton
polarization are represented as a contraction of the electron structure and the
hard part of the polarization dependent contribution into cross-section. The
calculation of the hard part with first order radiative correction is
performed. The obtained representation includes the leading radiative
corrections in all orders of perturbation theory and the main part of the
second order next-to-leading ones. Numerical calculations illustrate our
analytical results.

</DOC>
<DOC>
<DOCNO> 120517 </DOCNO>
Dust Emission Features in NGC 7023 between 0.35 and 2.5 micron: Extended


  We present 0.35 to 2.5 micron spectra of the south and northwest filaments in
the reflection nebula NGC 7023. These spectra were used to test the theory of
Seahra & Duley that carbon nanoparticles are responsible for Extended Red
Emission (ERE). Our spectra fail to show their predicted second emission band
at 1.0 micron even though both filaments exhibit strong emission in the
familiar 0.7 micron ERE band. The northwest filament spectrum does show one,
and possibly two, new dust emission features in the near-infrared. We clearly
detect a strong emission band at 1.5 micron which we tentatively attribute to
beta-FeSi_2 grains. We tentatively detect a weaker emission band at 1.15 micron
which coincides with the location expected for transitions from the conduction
band to mid-gap defect states of silicon nanoparticles. This is added evidence
that silicon nanoparticles are responsible for ERE as they already can explain
the observed behavior of the main visible ERE band.

</DOC>
<DOC>
<DOCNO> 68142 </DOCNO>
Constraints on a Model with Pure Right-Handed Third Generation Couplings


  We examine constraints on a model with pure right-handed third generation
charged couplings. The parameters of the right-handed mixing matrix and the
right-handed coupling strength are constrained from semi-leptonic B decays, the
mass difference of neutral mesons, the CP violating observables epsilon and
epsilon', and the electric dipole moment of the neutron. We find the model to
be tightly constrained by these parameters with several fine tuning conditions
on the phases in the right-handed mixing matrix. There is also a necessarily
non-zero value of the left and right W mixing parameter. CP asymmetry phases in
neutral B decays are discussed.

</DOC>
<DOC>
<DOCNO> 174456 </DOCNO>
Isotopic Composition of Fragments in Nuclear Multifragmentation


  The isotope yields of fragments, produced in the decay of the quasiprojectile
in Au+Au peripheral collisions at 35 MeV/nucleon and those coming from the
disassembly of the unique source formed in Xe+Cu central reactions at 30
MeV/nucleon, were measured. We show that the relative yields of neutron-rich
isotopes increase with the excitation energy in multifragmentation reaction. In
the framework of the statistical multifragmentation model which fairly well
reproduces the experimental observables, this behaviour can be explained by
increasing N/Z ratio of hot primary fragments, that corresponds to the
statistical evolution of the decay mechanism with the excitation energy: from a
compound-like decay to complete multifragmentation.

</DOC>
<DOC>
<DOCNO> 85068 </DOCNO>
Self force on charges in the spacetime of spherical shells


  We study the self force acting on static electric or scalar charges inside or
outside a spherical, massive, thin shell. The regularization of the self force
is done using the recently-proposed Mode Sum Regularization Prescription. In
all cases the self force acting on the charge is repulsive. We find that in the
scalar case the force is quadratic in the mass of the shell, and is a second
post-Newtonian effect. For the electric case the force is linear in the shell's
mass, and is a first post-Newtonian effect. When the charge is outside the
shell our results correct the known zero self force in the scalar case or the
known repulsive, inverse-cubic force law in the electric case, for the finite
size of the shell. When the charge is near the center of the shell the charge
undergoes harmonic oscillations.

</DOC>
<DOC>
<DOCNO> 118388 </DOCNO>
Slim Disk Model for Soft X-Ray Excess and Variability of Narrow-Line


  Narrow-line Seyfert 1 galaxies (NLS1s) exhibit extreme soft X-ray excess and
large variability. We argue that both features can be basically accounted for
by the slim disk model. We assume that a central black-hole mass in NLS1 is
relatively small, $M \sim 10^{5-7}M_\odot$, and that a disk shines nearly at
the Eddington luminosity, $L_{\rm E}$. Then, the disk becomes a slim disk and
exhibits the following distinctive signatures: (1) The disk luminosity
(particularly of X-rays) is insensitive to mass-flow rates, $\dot M$, since the
generated energy is partly carried away to the black hole by trapped photons in
accretion flow. (2) The spectra are multi-color blackbody. The maximum
blackbody temperature is $T_{\rm bb} \simeq 0.2(M/10^5 M_\odot)^{-1/4}$ keV,
and the size of the blackbody emitting region is small, $r_{\rm bb} \lsim 3
r_{\rm S}$ (with $r_{\rm S}$ being Schwarzschild radius) even for a
Schwarzschild black hole. (3) All the ASCA observation data of NLS1s fall onto
the region of $\dot M/(L_{\rm E}/c^2)>10$ (with $L_{\rm E}$ being the Eddington
luminosity) on the ($r_{\rm bb},T_{\rm bb}$) plane, supporting our view that a
slim disk emits soft X-rays at $\sim L_{\rm E}$ in NLS1s. (4) Magnetic energy
can be amplified, at most, up to the equipartition value with the trapped
radiation energy which greatly exceeds radiation energy emitted from the disk.
Hence, energy release by consecutive magnetic reconnection will give rise to
substantial variability in soft X-ray emission.

</DOC>
<DOC>
<DOCNO> 102894 </DOCNO>
On the geometric Langlands conjecture


  Let X be a smooth, complete, geometrically connected curve over a field of
characteristic p. The geometric Langlands conjecture states that to each
irreducible rank n local system E on X one can attach a perverse sheaf on the
moduli stack of rank n bundles on X (irreducible on each connected component),
which is a Hecke eigensheaf with respect to E. In this paper we derive the
geometric Langlands conjecture from a certain vanishing conjecture.
Furthermore, using recent results of Lafforgue, we prove this vanishing
conjecture, and hence the geometric Langlands conjecture, in the case when the
ground field is finite.

</DOC>
<DOC>
<DOCNO> 150732 </DOCNO>
From cool pions to the chiral phase transition


  Using the ideas of effective field theory and dimensional reduction, we
relate the parameters of two low energy models of QCD: the O(N) nonlinear sigma
model in D=3+1, which describes the dynamics of cool pions, and the O(N)
Heisenberg magnet in D=3+0, which is commonly argued to reproduce the correct
critical behaviour of the chiral phase transition. As a result, we obtain a
generalized expression for the finite temperature pion decay constant which
reproduces, in certain limits, the available expressions in the literature.

</DOC>
<DOC>
<DOCNO> 9662 </DOCNO>
Rotational and vibrational spectra of quantum rings


  One can confine the two-dimensional electron gas in semiconductor
heterostructures electrostatically or by etching techniques such that a small
electron island is formed. These man-made ``artificial atoms'' provide the
experimental realization of a text-book example of many-particle physics: a
finite number of quantum particles in a trap. Much effort was spent on making
such "quantum dots" smaller and going from the mesoscopic to the quantum
regime. Far-reaching analogies to the physics of atoms, nuclei or metal
clusters were obvious from the very beginning: The concepts of shell structure
and Hund's rules were found to apply -- just as in real atoms! In this Letter,
we report the discovery that electrons confined in ring-shaped quantum dots
form rather rigid molecules with antiferromagnetic order in the ground state.
This can be seen best from an analysis of the rotational and vibrational
excitations.

</DOC>
<DOC>
<DOCNO> 69960 </DOCNO>
B ->PV Decays in the QCD Improved Factorization Approach


  Motivated by recent CELO measurements and the progress of the theory of B
decays, we investigate $B\to P V(P=\pi,K. V= K^{*},\rho,\omega)$ decay modes in
the framework of QCD improved factorization. We find that all the measured
branching ratios are well accommodated in the reasonable parameter space and
predictions for the other decay modes are well below the experimental upper
limits. We also have calculated CP asymmetries in these decay modes.

</DOC>
<DOC>
<DOCNO> 39709 </DOCNO>
Aspects of GMSB Phenomenology at TeV Colliders


  The status of two on-going studies concerning important aspects of the
phenomenology of gauge-mediated supersymmetry breaking (GMSB) models at TeV
colliders is reported. The first study deals with the characteristics of the
light Higgs boson spectrum allowed by the (minimal and non-minimal) GMSB
framework. Today's most accurate GMSB model generation and two-loop
Feynman-diagrammatic calculation of m_h have been combined. The Higgs masses
are shown in dependence of various model parameters at the messenger and
electroweak scales. In the minimal model, an upper limit on m_h of about 124
GeV is found for m_t = 175 GeV. The second study is focused on the measurement
of the fundamental SUSY breaking scale sqrt(F) at the LHC in the GMSB scenario
where a stau is the next-to-lightest SUSY particle (NLSP) and decays into a
gravitino with c*tau_NLSP in the range 0.5 m to 1 km. This implies the
measurement of mass and lifetime of long lived sleptons. The identification is
performed by determining the time of flight in the ATLAS muon chambers.
Accessible range and precision on sqrt(F) achievable with a counting method are
assessed.

</DOC>
<DOC>
<DOCNO> 170540 </DOCNO>
Spatial entanglement of twin quantum images


  We show that spatial entanglement of two twin images obtained by parametric
down-conversion is complete, i.e. concerns both amplitude and phase. This is
realised through a homodyne detection of these images which allows for
measurement of the field quadrature components. EPR correlations are shown to
exist between symmetrical pixels of the two images. The best possible
correlation is obtained by adjusting the phase of the local oscillator field
(LO) in the area of maximal amplification. The results for quadrature
components hold unchanged even in absence of any input image i.e. for pure
parametric fluorescence. In this case they are not related to intensity and
phase fluctuations.

</DOC>
<DOC>
<DOCNO> 119871 </DOCNO>
A Search of the Zone of Avoidance in Scorpius


  An optical search of the Scorpius region - close to the Galactic bulge - has
revealed some 1400 partially-obscured galaxies. Redshifts have been obtained
for nearly a hundred of these objects. Preliminary indications of large-scale
structures are reported.

</DOC>
<DOC>
<DOCNO> 12254 </DOCNO>
Reply to Comment of Yang, Sun, and Chang on "Theory of Diluted Magnetic


  We reply to the comment cond-mat/0008098 by Yang, Sun, and Chang on our paper
"Theory of Diluted Magnetic Semiconductor Ferromagnetism", Phys. Rev. Lett. 84,
5628 (2000).

</DOC>
<DOC>
<DOCNO> 122110 </DOCNO>
The Optical and Near-Infrared Morphologies of Isolated Early Type


  In order to study early type galaxies in their simplest environments, we have
constructed a well-defined sample of 30 isolated galaxies. The sample contains
all RC3 early-type galaxies with no other cataloged galaxy with known redshift
lying within a projected radius of 1 (h_100)^{-1} Mpc and =/- 1000 km/s (where
we use the recessional velocities in the RC3). We have obtained optical and
near-infrared images of 23 of the galaxies and of a comparison sample of 13
early-type galaxies in X-ray detected poor groups of galaxies. We have applied
the techniques of unsharp masking, galaxy model division, and color maps to
search for morphological features that might provide clues to the evolution of
these galaxies. Evidence for dust features is found in approximately 75% of
both the isolated and group galaxies (17 of 22 and 9 of 12, respectively).
However, shells or tidal features are much more prevalent in our isolated
sample than in our group sample (9 of 22 or 41% versus 1 of 12 or 8%,
respectively). The isolation and colors of these shell galaxies make it
unlikely that tidal interactions or asymmetric star formation are the causes of
such features. One model that is not ruled out is that mergers produce the
shells. If shells and dust are both merger signatures, the absence of shells in
group ellipticals implies that shells: 1) form more easily, 2) are younger,
and/or 3) are longer-lived in isolated environments.

</DOC>
<DOC>
<DOCNO> 123132 </DOCNO>
New Perspectives on Cooling Flows and Cluster Radio Sources


  We discuss new results from the Chandra X-ray Observatory and XMM-Newton on
cluster cooling flows, emphasizing early results from our Chandra programs. We
find cooling rates reduced by factors of 5-10 compared to those from earlier
missions. Nevertheless, substantial amounts of keV gas appear to be cooling and
fueling star formation in central dominant cluster galaxies (CDGs). The
structure of the keV thermal gas is remarkably complex, particularly in regions
surrounding the the radio source and sites of star formation in CDGs. The radio
sources are displacing the thermal gas leaving cavities filled with radio
emission. The cavities are apparently supported against the local gas pressure
by magnetic fields and cosmic rays. In addition, radio-faint, ``ghost''
cavities are seen in some clusters. They may be relics of earlier radio
outbursts rising buoyantly in the intracluster medium. The radio sources may
reduce the mass deposition rates by mechanical heating, and by inducing
convective currents that move cool material outward.

</DOC>
<DOC>
<DOCNO> 11058 </DOCNO>
Large non-adiabatic hole polarons and matrix element effects in the


  It has been made an extention of the conventional theory based on the
assumption of the well isolated Zhang-Rice singlet to be a first
electron-removal state in dielectric copper oxide. One assumes the photohole
has been localised on either small (pseudo)Jahn-Teller polaron or large
non-adiabatic polaron enclosed one or four to five $CuO_4$ centers,
respectively, with active one-center valent $(^{1}A_{1g}-{}^{1,3}E_{u})$
manifold. In the framework of the cluster model we have performed a model
microscopic calculation of the ${\bf k}$-dependence of the matrix element
effects and photon polarization effects for the angle-resolved photoemission in
dielectric cuprate like $Sr_{2}CuO_{2}Cl_{2}$. We show that effects like the
''remnant Fermi surface'' detected in ARPES experiment for
$Ca_{2}CuO_{2}Cl_{2}$ may be, in fact, a reflection of the matrix element
effects, not a reflection of the original band-structure Fermi surface, or the
strong antiferromagnetic correlations. The measured dispersion-like features in
the low-energy part of the ARPES spectra may be a manifestation of the complex
momentum-dependent spectral line-shape of the large PJT polaron response, not
the dispersion of the well-isolated Zhang-Rice singlet in antiferromagnetic
matrix.

</DOC>
<DOC>
<DOCNO> 169790 </DOCNO>
The Representation of Natural Numbers in Quantum Mechanics


  This paper represents one approach to making explicit some of the assumptions
and conditions implied in the widespread representation of numbers by composite
quantum systems. Any nonempty set and associated operations is a set of natural
numbers or a model of arithmetic if the set and operations satisfy the axioms
of number theory or arithmetic. This work is limited to k-ary representations
of length L and to the axioms for arithmetic modulo k^{L}. A model of the
axioms is described based on states in and operators on an abstract L fold
tensor product Hilbert space H^{arith}. Unitary maps of this space onto a
physical parameter based product space H^{phy} are then described. Each of
these maps makes states in H^{phy}, and the induced operators, a model of the
axioms. Consequences of the existence of many of these maps are discussed along
with the dependence of Grover's and Shor's Algorithms on these maps. The
importance of the main physical requirement, that the basic arithmetic
operations are efficiently implementable, is discussed. This conditions states
that there exist physically realizable Hamiltonians that can implement the
basic arithmetic operations and that the space-time and thermodynamic resources
required are polynomial in L.

</DOC>
<DOC>
<DOCNO> 151807 </DOCNO>
Field theory models for tachyon and gauge field string dynamics


  In hep-th/0008227, the unstable lump solution of \phi^3 theory was shown to
have a spectrum governed by the solvable Schroedinger equation with the \ell=3
reflectionless potential and was used as a model for tachyon condensation in
string theory. In this paper we study in detail an \ell\to \infty scalar field
theory model whose lump solution mimics remarkably the string theory setup: the
original field theory tachyon and the lump tachyon have the same mass, the
spectrum of the lump consists of equally spaced infinite levels, there is no
continuous spectrum, and nothing survives after tachyon condensation. We also
find exact solutions for lumps with codimension \ge 2, and show that that their
tensions satisfy (1/(2\pi)) (T_p/ T_{p+1})=e/(\sqrt{2\pi}) \approx 1.08. We
incorporate gauge fixed couplings to a U(1) gauge field which preserve
solvability and result in massless gauge fields on the lump.

</DOC>
<DOC>
<DOCNO> 84976 </DOCNO>
Causality of the brane universe


  Causal structure of the brane universe with respect to null geodesics in the
bulk spacetime is studied. It is pointed out that apparent causality violation
is possible for the brane universe which contains matter energy. It is also
shown that there is no 'horizon problem' in the Friedmann-Robertson-Walker
brane universe.

</DOC>
<DOC>
<DOCNO> 83383 </DOCNO>
A Tableaux Calculus for Ambiguous Quantification


  Coping with ambiguity has recently received a lot of attention in natural
language processing. Most work focuses on the semantic representation of
ambiguous expressions. In this paper we complement this work in two ways.
First, we provide an entailment relation for a language with ambiguous
expressions. Second, we give a sound and complete tableaux calculus for
reasoning with statements involving ambiguous quantification. The calculus
interleaves partial disambiguation steps with steps in a traditional deductive
process, so as to minimize and postpone branching in the proof process, and
thereby increases its efficiency.

</DOC>
<DOC>
<DOCNO> 71503 </DOCNO>
On the Radiative Corrections to the Pseudo-scalar Higgs Boson Mass


  We reexamine the one-loop corrections to the mass of the pseudo-scalar Higgs
boson, using the effective potential. In the absence of the chargino and
neutralino contributions its mass exhibits a large scale dependence in the
large $M_{1/2}$ regime, especially for values of $\tan \beta>20$. Thus,
although of electroweak origin, the heaviness of the $M_{1/2}$, in conjunction
with the largeness of $\tan \beta$, makes these corrections very important for
establishing a scale independent result and an unambiguous determination of the
pseudo-scalar mass in this region of the parameter space.

</DOC>
<DOC>
<DOCNO> 8033 </DOCNO>
Integer-spin Heisenberg Chains in a Staggered Magnetic Field. A


  We present here a nonlinear sigma-model (NL$\sigma$M) study of a spin-1
antiferromagnetic Heisenberg chain in an external commensurate staggered
magnetic field. We find, already at the mean-field level, excellent agreement
with recent and very accurate Density Matrix Renormalization Group (DMRG)
studies, and that up to the highest values of the field for which a comparison
is possible, for the staggered magnetization and the transverse spin gap.
Qualitative but not quantitative agreement is found between the NL$\sigma$M
predictions for the longitudinal spin gap and the DMRG results. The origin of
the discrepancies is traced and discussed. Our results allow for extensions to
higher-spin chains that have not yet been studied numerically, and the
predictions for a spin-2 chain are presented and discussed. Comparison is also
made with previous theoretical approaches that led instead to predictions in
disagreement with the DMRG results.

</DOC>
<DOC>
<DOCNO> 84630 </DOCNO>
Isotropization of Bianchi type models and a new FRW solution in


  Using scaled variables we are able to integrate an equation valid for
isotropic and anisotropic Bianchi type I, V, IX models in Brans-Dicke (BD)
theory. We analyze known and new solutions for these models in relation with
the possibility that anisotropic models asymptotically isotropize, and/or
possess inflationary properties. In particular, a new solution of curve
($k\neq0$) Friedmann-Robertson-Walker (FRW) cosmologies in Brans-Dicke theory
is analyzed.

</DOC>
<DOC>
<DOCNO> 102173 </DOCNO>
Elementary Transversality in the Schubert calculus in any Characteristic


  We give a characteristic-free proof that general codimension-1 Schubert
varieties meet transversally in a Grassmannian and in some related varieties.
Thus the corresponding intersection numbers computed in the Chow (and quantum
Chow) rings of these varieties are enumerative in all characteristics. We show
that known transversality results do not apply to these enumerative problems,
emphasizing the need for additional theoretical work on transversality. The
method of proof also strengthens some results in real enumerative geometry.

</DOC>
<DOC>
<DOCNO> 120057 </DOCNO>
The Far-Infrared emission of Radio Loud and Radio Quiet Quasars


  Continuum observations at radio, millimetre, infrared and soft X-ray energies
are presented for a sample of 22 quasars, consisting of flat and steep spectrum
radio loud, radio intermediate and radio quiet objects. The primary
observational distinctions, among the different kinds of quasars in the radio
and IR energy domains are studied using large observational datasets provided
by ISOPHOT on board the Infrared Space Observatory, by the IRAM interferometer,
by the sub-millimetre array SCUBA on JCMT, and by the European Southern
Observatory (ESO) facilities IRAC1 on the 2.2 m telescope and SEST.
  The spectral energy distributions of all quasars from radio to IR energies
are analyzed and modeled with non-thermal and thermal spectral components.
  The dominant mechanism emitting in the far/mid-IR is thermal dust emission in
all quasars, with the exception of flat spectrum radio loud quasars for which
the presence of thermal IR emission remains rather uncertain, since it is
difficult to separate it from the bright non-thermal component. The dust is
predominantly heated by the optical/ultraviolet radiation emitted from the
external components of the AGN. A starburst contributes to the IR emission at
different levels, but always less than the AGN (< 27%). The distribution of
temperatures, sizes, masses, and luminosities of the emitting dust are
independent of the quasar type.

</DOC>
<DOC>
<DOCNO> 121743 </DOCNO>
Dynamics of Stellar Collisions


  I compare gas-dynamical and stellar-dynamical models of collisions. These two
models have distinctly different physics; for example, shocks introduce
irreversibility in gas systems, while stellar systems evolve in a completely
reversible fashion. Nonetheless, both models yield broadly similar results,
suggesting that analogies between gas and stellar dynamics have some heuristic
validity even applied to collisions.

</DOC>
<DOC>
<DOCNO> 80660 </DOCNO>
M[any] Vacua of IIB


  Description of the spectrum of fluctuations around a commutative vacuum
solution, as well as around a solution with degenerate commutator in IIB matrix
model is given in terms of supersymmetric Yang-Mills (YM) model. We construct
explicitly the map from Hermitian matrices to YM fields and study the
dependence of the spectrum and respective YM model on the symmetries of the
solution. The gauge algebra of the YM model is shown to contain local
reparameterisation algebra as well as Virasoro one.

</DOC>
<DOC>
<DOCNO> 8613 </DOCNO>
Spin - glass transition in Kondo lattice with quenched disorder


  We use the Popov-Fedotov representation of spin operators to construct an
effective action for a Kondo lattice model with quenched disorder at finite
temperatures. We study the competition between the Kondo effect and frozen spin
order in Ising-like spin glass. We present the derivation of new mean-field
equations for the spin-glass order parameter and analyze the effects of
screening of localized spins by conduction electrons on the spin-glass phase
transition.

</DOC>
<DOC>
<DOCNO> 70201 </DOCNO>
Effects of Higher-Order Threshold Corrections in High-E_T Jet Production


  Results for higher-order threshold enhancements in high-E_T jet production in
hadron-hadron collisions are presented. Expressions are given for the
next-to-next-to-leading order (NNLO) threshold corrections to the single-jet
inclusive cross section at next-to-leading logarithmic (NLL) accuracy. The
corrections are found to be small for the specific choice of E_T/2 for the
factorization and renormalization scales, and the corrected cross section shows
a substantial reduction of the scale dependence. A comparison to experimental
results from the Tevatron is presented.

</DOC>
<DOC>
<DOCNO> 85075 </DOCNO>
Energy for N-Body Motion in Two Dimensional Gravity


  A general definition of energy is given, via the N\"other theorem, for the
N-body problem in (1+1) dimensional gravity. Within a first-order Lagrangian
framework, the density of energy of a solution relative to a background is
identified with the superpotential of the theory. For specific applications we
reproduce the expected Hamiltonian for the motion of N particles in a curved
spacetime. This Hamiltonian agrees with that found through an ADM-like
prescription for the energy when the latter is applicable but it also extends
to a wider class of solutions provided a suitable background is chosen.

</DOC>
<DOC>
<DOCNO> 85436 </DOCNO>
On the Hawking effect


  In terms of the Painlev{\'e}-Gullstrand-Lema{\^\i}tre coordinates a rather
general scenario for the gravitational collapse of an object and the subsequent
formation of a horizon is described by a manifestly $C^\infty$-metric. For a
1+1 dimensional model of the collapse the leading contributions to the
Bogoliubov coefficients are calculated explicitely and the Hawking temperature
is recovered. But depending on the particular dynamics of the collapse the
final state represents either evaporation or anti-evaporation. The
generalization of the calculation to 3+1 dimensions is outlined and possible
implications are addressed. PACS-numbers: 04.70.Dy, 04.70.-s, 04.62.+v.

</DOC>
<DOC>
<DOCNO> 71943 </DOCNO>
Diffraction at HERA and Prospects with H1


  In the context of the tremendous progress achieved at HERA in diffraction and
the need for a new level of statistical and systematic precision, the new very
large acceptance forward spectrometer planned by H1 (VFPS) is presented and the
physics issues are stressed.

</DOC>
<DOC>
<DOCNO> 99455 </DOCNO>
How many Turing degrees are there?


  A Borel equivalence relation on a Polish space is said to be countable if all
of its equivalence classes are countable. Standard examples of countable Borel
equivalence relations (on the space of subsets of the integers) that occur in
recursion theory are: recursive isomorphism, Turing equivalence, arithmetic
equivalence, etc. There is a canonical hierarchy of complexity of countable
Borel equivalence relations imposed by the notion of Borel reducibility. We
will survey results and conjectures concerning the problem of identifying the
place in this hierarchy of these equivalence relations from recursion theory
and also discuss some of their implications.

</DOC>
<DOC>
<DOCNO> 12567 </DOCNO>
Josephson Coupling, Phase Correlations, and Josephson Plasma Resonance


  Josephson plasma resonance has been introduced recently as a powerful tool to
probe interlayer Josephson coupling in different regions of the vortex phase
diagram in layered superconductors. In the liquid phase, the high temperature
expansion with respect to the Josephson coupling connects the Josephson plasma
frequency with the phase correlation function. This function, in turn, is
directly related to the pair distribution function of the liquid. We develop a
recipe to extract the phase and density correlation functions from the
dependencies of the plasma resonance frequency $\omega_p({\bf B})$ and the $c$
axis conductivity $\sigma_c({\bf B}) $ on the {\it ab}-component of the
magnetic field at fixed {\it c} -component. Using Langevin dynamic simulations
of two-dimensional vortex arrays we calculate density and phase correlation
functions at different temperatures. Calculated phase correlations describe
very well the experimental angular dependence of the plasma resonance field. We
also demonstrate that in the case of weak damping in the liquid phase,
broadening of the JPR line is caused mainly by random Josephson coupling
arising from the density fluctuations of pancake vortices. In this case the JPR
line has a universal shape, which is determined only by parameters of the
superconductors and temperature.

</DOC>
<DOC>
<DOCNO> 151654 </DOCNO>
Quantum Mechanics on a Noncommutative Brane in M(atrix) Theory


  We consider the quantum mechanics of a particle on a noncommutative
two-sphere with the coordinates obeying an SU(2)-algebra. The momentum operator
can be constructed in terms of an $SU(2)\times SU(2)$-extension and the
Heisenberg algebra recovered in the smooth manifold limit. Similar
considerations apply to the more general SU(n) case.

</DOC>
<DOC>
<DOCNO> 100317 </DOCNO>
The chain property for the associated primes of A-graded ideals


  We investigate how the chain property for the associated primes of monomial
degenerations of toric (or lattice) ideals can be generalized to arbitrary
A-graded ideals. The generalization works in dimension d=2, but it fails for
d>2.

</DOC>
<DOC>
<DOCNO> 101782 </DOCNO>
Metrical Multi-Time Lagrange Geometry of Physical Fields


  The author exposes the metrical multi-time Lagrange geometry of physical
fields which naturally generalizes the classical Lagrangian developped by Miron
and Anastasiei. In other words, one constructs a natural theory of physical
fields on the 1-jet fibre bundle, attached to a Kronecker h-regular multi-time
Lagrangian with partial derivatives of order one.

</DOC>
<DOC>
<DOCNO> 99398 </DOCNO>
Finite jet determination of holomorphic mappings at the boundary


  Let M,M' be smooth real hypersurfaces in N-dimensional space and assume that
M is k-nondegenerate at a point p in M. We prove that holomorphic mappings that
extend smoothly to M, sending a neighborhood of p in M diffeomorphically into
M' are completely determined by their 2k-jet at p. As an application of this
result, we also give sufficient conditions on a smooth real hypersurface which
guarantee that the space of infinitesimal CR automorphisms is finite
dimensional.

</DOC>
<DOC>
<DOCNO> 10143 </DOCNO>
Mesoscopic Spin Tunneling in Molecular Crystals


  The phenomenon of Quantum Tunneling of Mesoscopic Spins is reviewed in the
light of the behavior of the archetype of these systems: the molecular complex
Mn12-ac. Most observations can be understood in the framework of the reduced
Hilbert space dimension 2S+1=21. Due to the large spin S=10, the energy barrier
preventing spin rotation is large, and as a consequence, quantum relaxation is
very slow. The application of a magnetic field of a few Tesla below 1 K allows
to observe tunneling (i) between the states m=-10 and m=10-n with n=8 to 11 if
the field is longitudinal, or (ii) between the two ground-states m~-10 and m~10
if the field is transverse. The crossover temperature between ground-state and
thermally assisted tunneling in a longitudinal field extrapolates in zero field
at ~1.7 K. The observation of square root relaxation at
short-times/low-temperatures and of exponential relaxation at
long-times/high-temperatures, as observed previously above 1.5 K, confirms the
important role of the spin bath dynamics which is out of equilibrium in the
first regime and at equilibrium in the second one. In a second part of this
paper a new molecule, so-called V15, with resultant spin S=1/2 is investigated.
Contrary to high spin molecules, the energy barrier of low spin molecules is
small or null, and the splitting between the symmetrical and anti-symmetrical
states is sufficiently large to allow spin-phonon transitions during spin
rotation. In low spin molecules the coupling to the environment is quite
different from the one found in large spin molecules in low fields.

</DOC>
<DOC>
<DOCNO> 85465 </DOCNO>
Radion on the de Sitter brane


  The radion on the de Sitter brane is investigated at the linear perturbation
level, using the covariant curvature tensor formalism developed by Shiromizu,
Maeda and Sasaki. It is found that if there is only one de Sitter brane with
positive tension, there is no radion and thus the ordinary Einstein gravity is
recoverd on the brane other than corrections due to the massive Kaluza-Klein
modes. As a by-product of using the covariant curvature tensor formalism, it is
immediately seen that the cosmological scalar, vector and tensor type
perturbations all have the same Kaluza-Klein spectrum. On the other hand, if
there are two branes with positive and negative tensions, the gravity on each
brane takes corrections from the radion mode in addition to the Kaluza-Klein
modes and the radion is found to have a negative mass-squared proportional to
the curvature of the de Sitter brane, in contrast to the flat brane case in
which the radion mass vanishes and degenerates with the 4-dimensional graviton
modes. To relate our result with the metric perturbation approach, we derive
the second order action for the brane displacement. We find that the radion
identified in our approach indeed corresponds to the relative displacement of
the branes in the Randall-Sundrum gauge and describes the scalar curvature
perturbations of the branes in the gaussian normal coordinates around the
branes. Implications to the inflationary brane universe are briefly discussed.

</DOC>
<DOC>
<DOCNO> 170442 </DOCNO>
Homodyne characterization of active optical media


  An effective maximum likelihood method is suggested to characterize the
absorption/amplification properties of active optical media through homodyne
detection.

</DOC>
<DOC>
<DOCNO> 39855 </DOCNO>
Maximal $\nu_e$ oscillations, Borexino and smoking guns


  We examine the maximal $\nu_e --> \nu_s$ and $\nu_e --> \nu_\mu,\tau$
oscillation solutions to the solar neutrino problem. These solutions lead to
roughly a 50% solar flux reduction for the large parameter range $3\times
10^{-10} < \delta m^2/eV^2 < 10^{-3}$. It is known that the earth regeneration
effect may cause a potentially large night-day asymmetry even for maximal
neutrino oscillations. We investigate the night-day asymmetry predictions for
the forthcoming Borexino measurement of the ^7Be neutrinos for both maximal
$\nu_e --> \nu_s$ and $\nu_e --> \nu_\mu,\tau$ oscillations. If $y \times
10^{-8} < \delta m^2/eV^2 < 4y \times 10^{-5}$ (with y = 0.5 for $\nu_e -->
\nu_s$ case and y = 1 for $\nu_e --> \nu_\mu,\tau$ case) then the maximal
neutrino oscillations will lead to observable night-day asymmetries in Borexino
and/or superKamiokande. With Kamland covering the high mass range, $10^{-5} <
\delta m^2/eV^2 < 10^{-3}$ and Borexino/superK covering the low mass range,
$3\times 10^{-10} < \delta m^2/eV^2 < 5\times 10^{-9}$ ("just so" region),
essentially all of the $\delta m^2$ parameter space will soon be scrutinized.

</DOC>
<DOC>
<DOCNO> 102142 </DOCNO>
On the algebraicization of certain Stein manifolds


  To every real analytic Riemannian manifold M there is associated a complex
structure on a neighborhood of the zero section in the real tangent bundle of
M. This structure can be uniquely specified in several ways, and is referred to
as a Grauert tube. We say that a Grauert tube is entire if the complex
structure can be extended to the entire tangent bundle. We prove here that the
complex manifold given by an entire Grauert tube is, in a canonical way, an
affine algebraic variety. In the special case M = the 2-sphere, we show that
any entire Grauert tube associated to a metric (not necessarily round) on M
must be algebraically biholomorphic to the Grauert tube of the round metric,
that is, the non-singular quadric surface in complex affine 3-space. (This
second result has been discovered independently by B. Totaro.)

</DOC>
<DOC>
<DOCNO> 121651 </DOCNO>
Further Investigation of the Time Delay, Magnification Ratios, and


  High precision VLA flux density measurements for the lensed images of
0218+357 yield a time delay of 10.1(+1.5-1.6)days (95% confidence). This is
consistent with independent measurements carried out at the same epoch (Biggs
et al. 1999), lending confidence in the robustness of the time delay
measurement. However, since both measurements make use of the same features in
the light curves, it is possible that the effects of unmodelled processes, such
as scintillation or microlensing, are biasing both time delay measurements in
the same way. Our time delay estimates result in confidence intervals that are
somewhat larger than those of Biggs et al., probably because we adopt a more
general model of the source variability, allowing for constant and variable
components. When considered in relation to the lens mass model of Biggs et al.,
our best-fit time delay implies a Hubble constant of H_o = 71(+17-23) km/s-Mpc
for Omega_o=1 and lambda_o=0 (95% confidence; filled beam). This confidence
interval for H_o does not reflect systematic error, which may be substantial,
due to uncertainty in the position of the lens galaxy. We also measure the flux
ratio of the variable components of 0218+357, a measurement of a small region
that should more closely represent the true lens magnification ratio. We find
ratios of 3.2(+0.3-0.4) (95% confidence; 8 GHz) and 4.3(+0.5-0.8) (15 GHz).
Unlike the reported flux ratios on scales of 0.1", these ratios are not
strongly significantly different. We investigate the significance of apparent
differences in the variability properties of the two images of the background
active galactic nucleus. We conclude that the differences are not significant,
and that time series much longer than our 100-day time series will be required
to investigate propagation effects in this way.

</DOC>
<DOC>
<DOCNO> 68996 </DOCNO>
Pade-Improved Estimates of Hadronic Higgs Decay Rates


  Asymptotic Pade-approximant methods are utilized to estimate the order
$\alpha_s^5$ contribution to the $H\to gg$ rate and the order $\alpha_s^4$
contribution to the $H \to b \bar{b}$ rate. The former process is of particular
interest because of the slow convergence evident from the three known terms of
its QCD series, which begins with an order $\alpha_s^2$ leading-order term. The
order $\alpha_s^5$ contribution to the $H \to gg$ rate is expressed as a
degree-3 polynomial in $L \equiv ln (\mu^2 / m_t^2 (\mu))$. We find that
asymptotic Pade-approximant predictions for the coefficients of $L$, $L^2$, and
$L^3$ are respectively within 1%, 2%, and 7% of true values extracted via
renormalization-group methods. Upon including the full set of next-order
coefficients, the $H \to gg$ rate is found to be virtually scale-independent
over the 0.3 $M_{H} < \mu < M_t$ range of the renormalization scale-parameter
$\mu$. We conclude by discussing the small order $\alpha_s^4$ contribution to
the $H \to b \bar{b}$ rate, which is obtained from a prior asymptotic
Pade-approximant estimate of the order $\alpha_s^4$ contribution to the
quark-antiquark scalar-current correlation function.

</DOC>
<DOC>
<DOCNO> 68893 </DOCNO>
Large Extra Dimensions at Linear Colliders


  In this talk, I first present the motivation for theories wherein extra
spacetime dimensions can be compactified to have large magnitudes. In
particular, I discuss the Arkani-Hamed, Dimopoulos, Dvali (ADD) scenario. I
present the constraints that have been derived on these models from current
experiments and the expectations from future colliders. I concentrate
particularly on the possibilities of probing these extra dimensions at future
linear colliders.

</DOC>
<DOC>
<DOCNO> 102874 </DOCNO>
Noncommutative Instantons on the 4-Sphere from Quantum Groups


  We describe an approach to the noncommutative instantons on the 4-sphere
based on quantum group theory. We quantize the Hopf bundle S^7 --> S^4 making
use of the concept of quantum coisotropic subgroups. The analysis of the
semiclassical Poisson--Lie structure of U(4) shows that the diagonal SU(2) must
be conjugated to be properly quantized. The quantum coisotropic subgroup we
obtain is the standard SU_q(2); it determines a new deformation of the 4-sphere
Sigma^4_q as the algebra of coinvariants in S_q^7. We show that the quantum
vector bundle associated to the fundamental corepresentation of SU_q(2) is
finitely generated and projective and we compute the explicit projector. We
give the unitary representations of Sigma^4_q, we define two 0-summable
Fredholm modules and we compute the Chern-Connes pairing between the projector
and their characters. It comes out that even the zero class in cyclic homology
is non trivial.

</DOC>
<DOC>
<DOCNO> 71235 </DOCNO>
Minimal Hadronic Ansatz to Large-Nc QCD and Hadronic tau Decay


  I report on some recent work done in collaboration with Santi Peris and Boris
Phily (hep-ph/0007338) where, using the Aleph data on vector and axial-vector
spectral functions, we test simple duality properties of QCD in the large-Nc
limit which emerge in the approximation of a {\it minimal hadronic ansatz} of a
spectrum of narrow states. These duality properties relate the short- and
long-distance behaviours of specific correlation functions, which are order
parameters of spontaneous chiral symmetry breaking, in a way that we find well
supported by the data.

</DOC>
<DOC>
<DOCNO> 70670 </DOCNO>
Highlights of Cern Workshop on Charm Production in A+A Collisions


  Models and experimental effort concerning open and hidden charm production in
nuclear collisions discussed at Cern Workshop in December 99 are reviewed. The
most recent development is also mentioned.

</DOC>
<DOC>
<DOCNO> 100219 </DOCNO>
A Ring-Theorist's Description of Fedosov Quantization


  We present a formal, algebraic treatment of Fedosov's argument that the
coordinate algebra of a symplectic manifold has a deformation quantization. His
remarkable formulas are established in the context of affine symplectic
algebras.

</DOC>
<DOC>
<DOCNO> 84267 </DOCNO>
Peeling properties of lightlike signals in General Relativity


  The peeling properties of a lightlike signal propagating through a general
Bondi-Sachs vacuum spacetime and leaving behind another Bondi-Sachs vacuum
space-time are studied. We demonstrate that in general the peeling behavior is
the conventional one which is associated with a radiating isolated system and
that it becomes unconventional if the asymptotically flat space-times on either
side of the history of the light-like signal tend to flatness at future null
infinity faster than the general Bondi-Sachs space-time. This latter situation
occurs if, for example, the space-times in question are static Bondi-Sachs
space- times.

</DOC>
<DOC>
<DOCNO> 102837 </DOCNO>
On Cohen-Macaulay rings of invariants


  We investigate the transfer of the Cohen-Macaulay property from a commutative
ring to a subring of invariants under the action of a finite group. Our point
of view is ring theoretic and not a priori tailored to a particular type of
group action. As an illustration, we briefly discuss the special case of
multiplicative actions, that is, actions on group algebras $k[\bbZ^n]$ via an
action on $\bbZ^n$.

</DOC>
<DOC>
<DOCNO> 85084 </DOCNO>
Conserved Quantities in Kerr-anti-de Sitter Spacetimes in Various


  We compute the conserved charges for Kerr anti-de Sitter spacetimes in
various dimensions using the conformal and the counterterm prescriptions. We
show that the conserved charge corresponding to the global timelike killing
vector computed by the two methods differ by a constant dependent on the
rotation parameter and cosmological constant in odd spacetime dimensions,
whereas the charge corresponding to the rotational killing vector is the same
in either approach. We comment on possible implications of our results to the
AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 118763 </DOCNO>
What can GLAST say about the origin of cosmic rays in other galaxies ?


  Gamma rays in the band from 20 MeV to 300 GeV, used in combination with data
from radio and X-ray bands, provide a powerful tool for studying the origin of
cosmic rays in our sister galaxies Andromeda and the Magellanic Clouds.
Gamma-ray Large Area Space Telescope (GLAST) will spatially resolve these
galaxies and measure the spectrum and intensity of diffuse gamma radiation from
the collisions of cosmic rays with gas and dust in them. Observations of
Andromeda will give an external perspective on a spiral galaxy like the Milky
Way. Observations of the Magellanic Clouds will permit a study of cosmic rays
in dwarf irregular galaxies, where the confinement is certainly different and
the massive star formation rate is much greater.

</DOC>
<DOC>
<DOCNO> 121196 </DOCNO>
Modeling Mid-Ultraviolet Spectra. I. Temperatures of Metal-Poor Stars


  Determining the properties of old stellar systems using evolutionary
population synthesis requires a library of reliable model stellar fluxes.
Empirical libraries are limited to spectra of stars in the solar neighborhood,
with nearly solar abundances and abundance ratios. We report here a first step
towards providing a flux library that includes nonsolar abundances, based on
calculations from first principles that are calibrated empirically. We have
started with main-sequence stars, whose light dominates the mid-ultraviolet
spectrum of an old stellar system. We have calculated mid-ultraviolet spectra
for the Sun and nine nearby, near-main-sequence stars spanning metallicities
from less than 1/100 solar to greater than solar, encompassing a range of
light-element abundance enhancements. We first determined temperatures of eight
of the stars by analyzing optical echelle spectra together with the
mid-ultraviolet. Both could be matched at the same time only when models with
no convective overshoot were adopted, and only when an approximate chromosphere
was incorporated near the surface of relatively metal-rich models. Extensive
modifications to mid-UV line parameters were also required, notably the manual
assignment of approximate identifications for mid-UV lines missing from
laboratory linelists. Without recourse to additional missing opacity, these
measures suffice to reproduce in detail almost the entire mid-UV spectrum of
solar-temperature stars up to one-tenth solar metallicity, and the region from
2900A to 3100A throughout the entire metallicity range. Ramifications for
abundance determinations in individual metal-poor stars and for age-metallicity
determinations of old stellar systems are briefly discussed, with emphasis on
the predictive power of the calculations.

</DOC>
<DOC>
<DOCNO> 70856 </DOCNO>
Truncated BFKL Series and Hadronic Collisions


  A truncated BFKL series is studied and applied to hadronic processes. The
proton-(anti)proton cross sections are described with good agreement with data
and in a way consistent with the unitarity bound. The elastic scattering
amplitude is calculated at momentum transfer $t$ different from zero,
introducing two distinct ansatze for the proton impact factor. The elastic
differential cross section is obtained at small $t$ approximation and compared
with the data.

</DOC>
<DOC>
<DOCNO> 11141 </DOCNO>
Exact Ground State of the 2D Hubbard Model at Half Filling for $U=0^{+}$


  We solve analytically the $N\times N$ square lattice Hubbard model for even
$N$ at half filling and weak coupling by a new approach. The exact ground state
wave function provides an intriguing and appealing picture of the
antiferromagnetic order. Like at strong coupling, the ground state has total
momentum $K_{tot}=(0,0)$ and transforms as an $s$ wave for even $N/2$ and as a
$d$ wave otherwise.

</DOC>
<DOC>
<DOCNO> 117409 </DOCNO>
The discovery of the optical/IR counterpart of the 12s transient X-ray


  We report the discovery of the optical/infra-red counterpart of the 12.3s
transient X-ray pulsar GS0834-43. We re-analysed archival ROSAT PSPC
observations of GS0834-43, obtaining two new refined positions, about 14" and
18" away from the previously published one, and a new spin period measurement.
Within the new error circles we found a relatively faint (V=20.1) early type
reddened star (V-R=2.24). The optical spectrum shows a strong Halpha emission
line. The IR observations of the field confirm the presence of an IR excess for
the Halpha-emitting star (K'=11.4, J-K'=1.94) which is likely surrounded by a
conspicuous circumstellar envelope. Spectroscopic and photometric data indicate
a B0-2 V-IIIe spectral-type star located at a distance of 3-5kpc and confirm
the Be-star/X-ray binary nature of GS0834-43.

</DOC>
<DOC>
<DOCNO> 10716 </DOCNO>
Radiating dipoles in photonic crystals


  The radiation dynamics of a dipole antenna embedded in a Photonic Crystal are
modeled by an initially excited harmonic oscillator coupled to a non--Markovian
bath of harmonic oscillators representing the colored electromagnetic vacuum
within the crystal. Realistic coupling constants based on the natural modes of
the Photonic Crystal, i.e., Bloch waves and their associated dispersion
relation, are derived. For simple model systems, well-known results such as
decay times and emission spectra are reproduced. This approach enables direct
incorporation of realistic band structure computations into studies of
radiative emission from atoms and molecules within photonic crystals. We
therefore provide a predictive and interpretative tool for experiments in both
the microwave and optical regimes.

</DOC>
<DOC>
<DOCNO> 39739 </DOCNO>
Analytical and Numerical Flash-Algorithms for Track Fits


  Flash-algorithm track-reconstruction routines with speed factors 3000-4000 in
excess those of traditional iterative routines are presented.
 The methods were successfully tested in the alignment of the Test Beam setup
for the ATLAS Pixel Detector
 MCM-D modules yielding a
 60 fold increase in alignment resolution over iterative routines, for the same
amount of alocated CPU time.

</DOC>
<DOC>
<DOCNO> 151552 </DOCNO>
On the Fairlie's Moyal formulation of M(atrix)- theory


  Starting from the Moyal formulation of M-theory in the large N-limit, we
propose to reexamine the associated membrane equations of motion in 10
dimensions formulated in terms of Poisson bracket. Among the results obtained,
we rewrite the coupled first order Nahm's equations into a simple form leading
in turn to their systematic relation with $SU(\infty)$ Yang Mills equations of
motion. The former are interpreted as the vanishing condition of some conserved
currents which we propose. We develop also an algebraic analysis in which an
ansatz is considered and find an explicit form for the membrane solution of our
problem. Typical solutions known in literature can also emerge as special cases
of the proposed solution

</DOC>
<DOC>
<DOCNO> 11615 </DOCNO>
Effects of magnetic field induced chiral-spin interactions on


  It is known that in certain non-bipartite quasi-one dimensional spin systems
in a magnetic field, in addition to the usual Pauli coupling of the spins to
the field, new parity breaking three spin interactions, i.e. chiral spin
interactions, are induced at higher order due to virtual processes involving
the intrinsic electronic nature of the underlying spins. The strenght of these
interactions depend strongly on the orientation of the field, a feature which
can be exploited to detect chiral effects experimentally. In many spin systems,
these chiral interactions are generated and should be taken into account before
any comparison with experiments can be made. We study the effect of the chiral
interactions on certain quasi-one-dimensional gapped spin half systems and show
that they can potentially alter the physics expected from the Pauli coupling
alone. In particular, we demonstrate that these terms alter the universality
class of the C-IC transition in spin-tubes. More interestingly, in weakly
coupled XX zig-zag ladders, we find that the field induced chiral term can
close the singlet gap and drive a second order transition in the non-magnetic
singlet sector, which manifests itself as a two component Luttinger liquid-like
behaviour in the spin correlation functions. Finally, we discuss the relevance
of our results to experiments.

</DOC>
<DOC>
<DOCNO> 7950 </DOCNO>
Ordering Dynamics of Heisenberg Spins with Torque: Crossover, Spinwaves


  We study the effect of a torque induced by the local molecular field on the
phase ordering dynamics of the Heisenberg model when the total magnetization is
conserved. The torque drives the zero-temperature ordering dynamics to a new
fixed point, characterized by exponents $z=2$ and $\lambda \approx 5$. This
`torque-driven' fixed point is approached at times such that $g^2 t\gg 1$,
where $g$ is the strength of the torque. All physical quantities, like the
domain size $L(t)$ and the equal and unequal time correlation functions obey a
crossover scaling form over the entire range of $g$. An attempt to understand
this crossover behavior from the approximate Gaussian Closure Scheme fails
completely, implying that the dynamics at late times cannot be understood from
the dynamics of defects alone. We provide convincing arguments that the spin
configurations can be decomposed in terms of defects and spin-waves which
interact with each other even at late times. In the absence of the torque term,
the spin waves decay faster, but even so we find that the Gaussian closure
scheme is inconsistent. In the latter case the inconsistency may be remedied by
including corrections to a simple gaussian distribution. For completeness we
include a discussion of the ordering dynamics at $T_c$, where the torque is
shown to be relevant, with exponents $z=4-\epsilon/2$ and $\lambda = d$ (where
$\epsilon = 6-d$). We show to all orders in perturbation theory that
$\lambda=d$ as a consequence of the conservation law.

</DOC>
<DOC>
<DOCNO> 40005 </DOCNO>
Experimental Probes of Localized Gravity: On and Off the Wall


  The phenomenology of the Randall-Sundrum model of localized gravity is
analyzed in detail for the two scenarios where the Standard Model (SM) gauge
and matter fields are either confined to a TeV scale 3-brane or may propagate
in a slice of five dimensional anti-deSitter space. In the latter instance, we
derive the interactions of the graviton, gauge, and fermion Kaluza-Klein (KK)
states. The resulting phenomenological signatures are shown to be highly
dependent on the value of the 5-dimensional fermion mass and differ
substantially from the case where the SM fields lie on the TeV-brane. In both
scenarios, we examine the collider signatures for direct production of the
graviton and gauge KK towers as well as their induced contributions to
precision electroweak observables. These direct and indirect signatures are
found to play a complementary role in the exploration of the model parameter
space. In the case where the SM field content resides on the TeV-brane, we show
that the LHC can probe the full parameter space and hence will either discover
or exclude this model if the scale of electroweak physics on the 3-brane is
less than 10 TeV. We also show that spontaneous electroweak symmetry breaking
of the SM must take place on the TeV-brane.

</DOC>
<DOC>
<DOCNO> 150611 </DOCNO>
Quantum Field Theories on Null Surfaces


  We study the behaviour of quantum field theories defined on a surface $S$ as
it tends to a null surface $S_n$. In the case of a real, free scalar field
theory the above limiting procedure reduces the system to one with a finite
number of degrees of freedom. This system is shown to admit a one parameter
family of inequivalent quantizations. A duality symmetry present in the model
can be used to remove the quantum ambiguity at the self-dual point . In the
case of the non-linear $\sigma$-model with the Wess-Zumino-Witten term a
similar limiting behaviour is obtained. The quantization ambiguity in this case
however cannot be removed by any means.

</DOC>
<DOC>
<DOCNO> 118005 </DOCNO>
Extremely Red Objects in the Field of QSO 1213-0017: A Galaxy


  We have discovered a concentration of extremely red objects (EROs; R-K>6) in
the field of the z=2.69 quasar QSO 1213-0017 (UM 485), which is significantly
overabundant compared to the field ERO surface density. The optical/near-IR
colors of the EROs and numerous other red galaxies in this field are consistent
with elliptical galaxies at z=1-2. HST optical images for a subset of galaxies
show regular morphologies, most of them being disky or diffuse and without any
obvious evidence for interactions. Ground-based IR images show similar
morphologies, indicating any dust reddening in these objects is spatially
uniform. Optical spectroscopy with the W. M. Keck Telescope has found that four
of the red galaxies lie at <z>=1.31, and a fifth lies in the foreground at
z=1.20. Of the <z>=1.31 galaxies, one is a reddened AGN while the remaining
three have rest-frame UV absorption-line spectra characteristic of old (few
Gyr) stellar populations, similar to the old red galaxy LBDS 53W091 at z=1.55.
Including the MgII absorber seen in the QSO spectrum, we find five galaxies at
<z>=1.31 spread over 1.5 h_50^{-1} Mpc on the sky. These results suggest we
have discovered a coherent structure of old galaxies at high-redshift, possibly
associated with a massive galaxy cluster.

</DOC>
<DOC>
<DOCNO> 119162 </DOCNO>
High resolution Ks polarization mapping of OH 231.8+4.2 (OH 0739-14)


  The bipolar reflection nebula OH 231.8+4.2 (OH 0739-14), centred on the Mira
variable star QX Pup, has been mapped at Ks in linear polarization using the
ESO SOFI near-infrared multi-mode instrument. The large scale linear
polarization features agree with previous studies, validating the polarimetric
mode of the instrument. However the high spatial resolution of the polarization
map reveals considerable structure, some of which finds correspondence in the
surface brightness images. The core is crossed by low polarization filaments;
the northern lobe reveals an axial finger and a rim of very high linear
polarization (upto 80%) whilst the southern lobe shows less polarization
contrast. There is a trend in polarization perpendicular to the bipolar axis in
both lobes. The individual linear polarization features most probably arise
from localised dust structures with distinct orientations leading to differing
polarization through single scattering. A single scattering geometric model,
consisting of two lobes of ellipsoidal section and a central dense disk, is
considered which can explain the general features of the intensity and
polarization images.

</DOC>
<DOC>
<DOCNO> 119860 </DOCNO>
The Impact of Galaxy Formation on the X-ray Evolution of Clusters


  We present a new model for the X-ray properties of the intracluster medium
that explicitly includes heating of the gas by the energy released during the
evolution of cluster galaxies. We calculate the evolution of clusters by
combining the semi-analytic model of galaxy formation of Cole et al. with a
simple model for the radial profile of the intracluster gas. We focus on the
cluster X-ray luminosity function and on the relation between X-ray temperature
and luminosity. We show that cooling alone is not enough to account for the
flatness of the observed T-L relation or for the lack of strong redshift
evolution in the observed X-ray luminosity function. Gas heating, on the other
hand, can solve these two problems: in the \Lambda-CDM cosmology, our model
reproduces fairly well the T-L relation and the X-ray luminosity function.
Furthermore, it predicts only weak evolution in these two properties out to
z=0.5, in agreement with recent observational data. A successful model requires
an energy input of 1--2 x 10^49 ergs per solar mass of stars formed. This is
comparable to the total energy released by the supernovae associated with the
formation of the cluster galaxies. Thus, unless the transfer of supernovae
energy to the intracluster gas is very (perhaps unrealistically) efficient,
additional sources of energy, such as mechanical energy from AGN winds are
required. However, the amplification of an initial energy input by the response
of the intracluster medium to protocluster mergers might ease the energy
requirements. Our model makes definite predictions for the X-ray properties of
groups and clusters at high redshift which may soon be tested with data from
the Chandra and Newton satellites.

</DOC>
<DOC>
<DOCNO> 10556 </DOCNO>
Polymer confinement in undulated membrane boxes and tubes


  We consider quantum particle or Gaussian polymer confinement between two
surfaces and in cylinders with sinusoidal undulations. In terms of the
variational method, we show that the quantum mechanical wave equations have
lower ground state energy in these geometries under long wavelength
undulations, where bulges are formed and waves are localized in the bulges. It
turns out correspondingly that Gaussian polymer chains in undulated boxes or
tubes acquire higher entropy than in exactly flat or straight ones. These
phenomena are explained by the uncertainty principle for quantum particles, and
by a "polymer confinement rule" for Gaussian polymers. If membrane boxes or
tubes are flexible, polymer-induced undulation instability is suggested. We
find that the wavelength of undulations at the threshold of instability for a
membrane box is almost twice the distance between two walls of the box.
Surprisingly we find that the instability for tubes begins with a shorter
wavelength compared to the "Rayleigh" area-minimizing instability.

</DOC>
<DOC>
<DOCNO> 99366 </DOCNO>
Local uniqueness for the Dirichlet-to-Neumann map via the two-plane


  We consider the Dirichlet-to-Neumann map associated to the Schr\"odinger
equation with a potential in a bounded Lipschitz domain in three or more
dimensions. We show that the integral of the potential over a two-plane is
determined by the Cauchy data of certain exponentially growing solutions on any
neighborhood of the intersection of the two-plane with the boundary.

</DOC>
<DOC>
<DOCNO> 178860 </DOCNO>
Interactions, Currents, and the Structure of Few-Nucleon Systems


  Our current understanding of the structure of nuclei with up to A=8,
including energy spectra, electromagnetic form factors, and weak transitions,
is reviewed within the context of a realistic approach to nuclear dynamics
based on two- and three- nucleon interactions and associated electro-weak
currents. Low-energy radiative and weak capture reactions of astrophysical
relevance involving these light systems are also discussed.

</DOC>
<DOC>
<DOCNO> 8575 </DOCNO>
Steady-state selection in driven diffusive systems with open boundaries


  We investigate the stationary states of one-dimensional driven diffusive
systems, coupled to boundary reservoirs with fixed particle densities. We argue
that the generic phase diagram is governed by an extremal principle for the
macroscopic current irrespective of the local dynamics. In particular, we
predict a minimal current phase for systems with local minimum in the
current--density relation. This phase is explained by a dynamical phenomenon,
the branching and coalescence of shocks, Monte-Carlo simulations confirm the
theoretical scenario.

</DOC>
<DOC>
<DOCNO> 151650 </DOCNO>
On Chapline-Manton couplings: a cohomological approach


  Chern-Simons couplings between Yang-Mills gauge fields and an abelian 2-form
are derived by means of cohomological arguments.

</DOC>
<DOC>
<DOCNO> 69514 </DOCNO>
Deuteron Breakup pd\to pnp in Specific Kinematics and Short-Range


  Deuteron breakup processes $p+d\to (NN)_{s,t}+N$ are studied in the
kinematics of backward elastic pd-scattering at law relative momenta of the
NN-pair $k\sim 0-50 MeV/c$ for initial energies $T_0=0.5-2.5 GeV$ in the
framework of the known mechanisms of the $pd\to dp$ process including
rescatterings in the initial and final states. A considerable suppression of
the $\Delta-$ and $N^*-$ isobar excitation mechanisms is found for the
production of the singlet $(NN)_s$-pair. As a result, one nucleon exchange
mechanism can be identified in the cross section and polarization observables
by the node of the half-off-shell NN$(~^1S_0)$-scattering amplitude, $t(q,k)$,
at $q\sim 0.4 $ GeV/c.

</DOC>
<DOC>
<DOCNO> 102286 </DOCNO>
On certain automorphisms of sets of partial isometries


  Under the mild condition of continuity at a single point we describe all the
bijections of the set of all partial isometries on a Hilbert space which
preserve the order and the orthogonality in both directions. Moreover, we
present a natural analogue of Wigner's theorem on quantum mechanical symmetries
for the set of all rank-1 partial isometries.

</DOC>
<DOC>
<DOCNO> 10653 </DOCNO>
Montecarlo simulation of the role of defects as the melting mechanism


  We study in this paper the melting transition of a crystal of fcc structure
with the Lennard-Jones potential, by using isobaric-isothermal Monte Carlo
simulations.
  Local and collective updates are sequentially used to optimize the
convergence. We show the important role played by defects in the melting
mechanism in favor of modern melting theories.

</DOC>
<DOC>
<DOCNO> 178428 </DOCNO>
Pion abundance and entropy in the hydrodynamical description of


  We show that a hydrodynamical model with continuous particle emission instead
of sudden freeze out can explain both the strange particle abundances and pion
abundance from NA35 without extra assumption (e.g., sequential freeze out,
modified equation of state, sudden plasma hadronization,...). In this scenario,
the observation of a larger pion abundance is natural and does not imply a
higher initial entropy and early plasma phase.

</DOC>
<DOC>
<DOCNO> 174547 </DOCNO>
Elliptic flow in Au+Au collisions at sqrt(s_NN) = 130 GeV


  Elliptic flow from nuclear collisions is a hadronic observable sensitive to
the early stages of system evolution. We report first results on elliptic flow
of charged particles at midrapidity in Au+Au collisions at sqrt(s_NN)=130 GeV
using the STAR TPC at RHIC. The elliptic flow signal, v_2, averaged over
transverse momentum, reaches values of about 6% for relatively peripheral
collisions and decreases for the more central collisions. This can be
interpreted as the observation of a higher degree of thermalization than at
lower collision energies. Pseudorapidity and transverse momentum dependence of
elliptic flow are also presented.

</DOC>
<DOC>
<DOCNO> 14148 </DOCNO>
Self-Similar Traffic Originating in the Transport Layer


  We performed a network traffic simulation to clarify the mechanism producing
self-similar traffic originating in the transport layer level. Self-similar
behavior could be observed without assuming a long-tailed distribution of the
input file size. By repeating simulations with modified TCP we found that the
feedback mechanism from the network, such as packet transmission driven by
acknowledgement packets, plays an essential role in explaining the
self-similarity observed in the actual traffic.

</DOC>
<DOC>
<DOCNO> 10350 </DOCNO>
Inherent structures and non-equilibrium dynamics of 1D constrained


  e discuss the relevance of the Stillinger and Weber approach to the glass
transition investigating the non-equilibrium behavior of models with
non-trivial dynamics, but with simple equilibrium properties. We consider a
family of 1D constrained kinetic models, which interpolates between the
asymmetric chain introduced by Eisinger and J\"ackle [Z. Phys. {\bf B84}, 115
(1991)] and the symmetric chain introduced by Fredrickson and Andersen [Phys.
Rev. Lett {\bf 53}, 1244 (1984)], and the 1D version of the Backgammon model
[Phys. Rev. Lett. {\bf 75}, 1190 (1995)]. We show that the configurational
entropy obtained from the inherent structures is the same for all models
irrespective of their different microscopic dynamics. We present a detailed
study of the coarsening behavior of these models, including the relation
between fluctuations and response. Our results suggest that any approach to the
glass transition inspired by mean-field ideas and resting on the definition of
a configurational entropy must rely on the absence of any growing
characteristic coarsening pattern.

</DOC>
<DOC>
<DOCNO> 152231 </DOCNO>
Boundary Dynamics of Higher Dimensional Chern-Simons Gravity


  We review the relevance to the black hole entropy problem of boundary
dynamics in Chern-Simons gravity. We then describe a recent derivation of the
action induced on the four dimensional boundary in a five dimensional
Chern-Simons gravity theory with gauge invariant, anti-deSitter boundary
conditions.

</DOC>
<DOC>
<DOCNO> 117735 </DOCNO>
Black Hole Formation and Gamma Ray Bursts


  Recent work on the dyadosphere of a black hole is reviewed with special
emphasis on the explanation of gamma ray bursts. A change of paradigm in the
observations of black holes is presented.

</DOC>
<DOC>
<DOCNO> 121020 </DOCNO>
Dynamical Masses of T Tauri Stars and Calibration of PMS Evolution


  We have used the high sensitivity and resolution of the IRAM interferometer
to produce sub-arcsecond 12CO 2-1 images of 9 protoplanetary disks surrounding
T Tauri stars in the Taurus-Auriga cloud (7 singles and 2 binaries). The images
demonstrate the disks are in Keplerian rotation around their central stars.
Using the least square fit method described in Guilloteau and Dutrey (1998), we
derive the disk properties, in particular its inclination angle and rotation
velocity, hence the dynamical mass. Since the disk mass is usually small, this
is a direct measurement of the stellar mass. Typically, we reach an internal
precision of 10% in the determinations of stellar mass. The over-all accuracy
is limited by the uncertainty in the distance to a specific star. In a distance
independent way, we compare the derived masses with theoretical tracks of
pre-main-sequence evolution. Combined with the mean distance to the Taurus
region (140 pc), for stars with mass close to 1 Msun, our results tend to favor
the tracks with cooler photospheres (higher masses for a given spectral type).
We find that in UZ Tau E the disk and the spectroscopic binary orbit appear to
have different inclinations.

</DOC>
<DOC>
<DOCNO> 102261 </DOCNO>
Generalized Metrical Multi-Time Lagrange Geometry of Physical Field


  The paper developes a geometrization of a Kronecker $h$-regular vertical
fundamental metrical d-tensor $G^{(\alpha)(\beta)}_{(i)(j)}$ on the jet fibre
bundle of order one $J^1(T,M)$. This geometrization gives a mathematical model
for both gravitational and electromagnetic field theory, in a general setting.
In this context, the Einstein and Maxwell equations are described.

</DOC>
<DOC>
<DOCNO> 83471 </DOCNO>
Systematic Debugging of Attribute Grammars


  Although attribute grammars are commonly used for compiler construction,
little investigation has been conducted on debugging attribute grammars. The
paper proposes two types of systematic debugging methods, an algorithmic
debugging and slice-based debugging, both tailored for attribute grammars. By
means of query-based interaction with the developer, our debugging methods
effectively narrow the potential bug space in the attribute grammar description
and eventually identify the incorrect attribution rule. We have incorporated
this technology in our visual debugging tool called Aki.

</DOC>
<DOC>
<DOCNO> 119021 </DOCNO>
Spectral Variations in Early-Type Galaxies as a Function of Mass


  We report on the strengths of three spectral indicators - Mg_2, Hbeta, and
Hn/Fe - in the integrated light of a sample of 100 field and cluster E/S0
galaxies. The measured indices are sensitive to age and/or and metallicity
variations within the galaxy sample. Using linear regression analysis for data
with non-uniform errors, we determine the intrinsic scatter present among the
spectral indices of our galaxy sample as a function of internal velocity
dispersion. Our analysis indicates that there is significantly more intrinsic
scatter in the two Balmer line indices than in the Mg_2 index, indicating that
the Balmer indices provide more dynamic range in determining the age of a
stellar population than does the Mg_2 index. Furthermore, the scatter is much
larger for the low velocity dispersion galaxies, indicating that star formation
has occurred more recently in the lower mass galaxies.

</DOC>
<DOC>
<DOCNO> 69502 </DOCNO>
Transverse momentum dependence of directed particle flow at 160 AGeV


  The transverse momentum ($p_t$) dependence of hadron flow at SPS energies is
studied. In particular, the nucleon and pion flow in S+S and Pb+Pb collisions
at 160 AGeV is investigated. For simulations the microscopic quark-gluon string
model (QGSM) is applied. It is found that the directed flow of pions $v_1(y,
\Delta p_t)$ changes sign from a negative slope in the low-$p_t$ region to a
positive slope at $p_t \geq 0.6$ GeV/c as recently also observed
experimentally. The change of the flow behaviour can be explained by early
emission times for high-$p_t$ pions. We further found that a substantial amount
of high-$p_t$ pions are produced in the very first primary NN collisions at the
surface region of the touching nuclei. Thus, at SPS energies high-$p_t$
nucleons seem to be a better probe for the hot and dense early phase of nuclear
collisions than high-$p_t$ pions. Both, in the light and in the heavy system
the pion directed flow $v_1(p_t, \Delta y)$ exhibits large negative values when
the transverse momentum approaches zero, as also seen experimentally in Pb+Pb
collisions. It is found that this effect is caused by nuclear shadowing. The
proton flow, in contrary, shows the typical linear increase with rising $p_t$.

</DOC>
<DOC>
<DOCNO> 70526 </DOCNO>
On the Relationship between Large Order Graphs and Instantons for the


  The double well oscillator is used as a QCD-like model for studying the
relationship between large order graphs and the instanton-antiinstanton
solution. We derive an equation for the perturbative coefficients of the ground
state energy when the number of 3 and/or 4-vertices is fixed and large. These
coefficients are determined in terms of an exact``bounce'' solution. When the
number of 4-vertices is analytically continued to be near the negative of half
the number of 3-vertices the bounce solution approaches the
instanton-antiinstanton solution and detremines leading Borel singularity.

</DOC>
<DOC>
<DOCNO> 122444 </DOCNO>
Models of Cuspy Triaxial Galaxies


  We construct numerical models of mildly triaxial elliptical galaxies with
central density cusps. Using a technique we call ``adiabatic squeezing'', we
begin with a spherical gamma=1 Hernquist model and apply a drag to the
velocities of the particles along each principle axis. The final models are
stable in isolation, preserving their density structure and figure shape over
many dynamical timescales. The density profile and axial ratios compare well to
the observed properties of elliptical galaxies. The orbital structure of these
models show a mixture of tubes, boxes, and boxlets, as expected for triaxial
systems, with very few chaotic orbits. These N-body realizations of cuspy
triaxial galaxies provide a basis for the study of the dynamical evolution of
elliptical galaxies.

</DOC>
<DOC>
<DOCNO> 170149 </DOCNO>
A Kochen-Specker inequality


  A Kochen-Specker inequality is presented, which enables a test for contextual
hidden-variable models at low experimental error rates. This is achieved by
formulating the concept of "probabilistic contextuality", possible to use in
non-ideal experiments. Assuming that the errors are independent, an explicit
error bound of 1.057% is derived, below which a Kochen-Specker contradiction
occurs for a certain set of vectors.

</DOC>
<DOC>
<DOCNO> 170638 </DOCNO>
Creating Bell states and decoherence effects in quantum dots system


  We show how to improve the efficiency for preparing Bell states in coupled
two quantum dots system. A measurement to the state of driven quantum laser
field leads to wave function collapse. This results in highly efficiency
preparation of Bell states. The effect of decoherence on the efficiency of
generating Bell states is also discussed in this paper. The results show that
the decoherence does not affect the relative weight of $|00>$ and $|11>$ in the
output state, but the efficiency of finding Bell states.

</DOC>
<DOC>
<DOCNO> 70246 </DOCNO>
The Gluon Propagator without lattice Gribov copies


  We study the gluon propagator in quenched lattice QCD using the Laplacian
gauge which is free of lattice Gribov copies. We compare our results with those
obtained in the Landau gauge on the lattice, as well as with various
approximate solutions of the Dyson Schwinger equations. We find a finite value
$\sim (445 \rm{MeV})^{-2}$ for the renormalized zero-momentum propagator
(taking our renormalization point at 1.943 GeV), and a pole mass $\sim 640 \pm
140$ MeV.

</DOC>
<DOC>
<DOCNO> 120081 </DOCNO>
ORFEUS II echelle spectra: On the influence of iron-group line


  We present an analysis of the subdwarf O star Feige 67 with a fully
metal-line blanketed NLTE model atmosphere based on high-resolution Far-UV
(912-2000 A) and Near-UV (2000-3400 A) spectra from new ORFEUS II echelle
observations and the IUE final archive. The Far-UV spectra are heavily
blanketed by iron and nickel lines, preventing the detection of the stellar
continuum and complicating the abundance analysis.
  Important points concerning the account for blanketing by millions of
iron-group lines and for an accurate determination of iron and nickel
abundances are discussed: The usage of all theoretically and experimentally
known line opacities of the iron-group elements, the consideration of a broad
wavelength range for a reliable determination of the stellar continuum flux,
and the role of interstellar reddening. This paper outlines a basic approach
for spectral analysis of future high-resolution Far-UV spectra of hot compact
stars. During this study we re-analyzed the iron and nickel abundance of our
exemplary object Feige 67 and confirm their extraordinarily amount.

</DOC>
<DOC>
<DOCNO> 8333 </DOCNO>
Adsorption of benzene on Si(100) from first principles


  Adsorption of benzene on the Si(100) surface is studied from first
principles. We find that the most stable configuration is a
tetra-$\sigma$-bonded structure characterized by one C-C double bond and four
C-Si bonds. A similar structure, obtained by rotating the benzene molecule by
90 degrees, lies slightly higher in energy. However, rather narrow wells on the
potential energy surface characterize these adsorption configurations. A
benzene molecule impinging on the Si surface is most likely to be adsorbed in
one of three different di-$\sigma$-bonded, metastable structures, characterized
by two C-Si bonds, and eventually converts into the lowest-energy
configurations. These results are consistent with recent experiments.

</DOC>
<DOC>
<DOCNO> 150962 </DOCNO>
Invariants in Supersymmetric Classical Mechanics


  The bosonic second invariant of SuperLiouville models in supersymmetric
classical mechanics is described.

</DOC>
<DOC>
<DOCNO> 83070 </DOCNO>
Adaptive simulated annealing (ASA): Lessons learned


  Adaptive simulated annealing (ASA) is a global optimization algorithm based
on an associated proof that the parameter space can be sampled much more
efficiently than by using other previous simulated annealing algorithms. The
author's ASA code has been publicly available for over two years. During this
time the author has volunteered to help people via e-mail, and the feedback
obtained has been used to further develop the code. Some lessons learned, in
particular some which are relevant to other simulated annealing algorithms, are
described.

</DOC>
<DOC>
<DOCNO> 70427 </DOCNO>
b --> s gamma confronts B-violating scalar couplings: R-parity violating


  We investigate the possible role that baryon number violating Yukawa
interactions may take in the inclusive decay $ B \to X_s \gamma$. The
constraints, derived using the experimental results of the CLEO collaboration,
turn out, in many cases, to be more stringent than the existing bounds.

</DOC>
<DOC>
<DOCNO> 121158 </DOCNO>
Chandra measurements of the distribution of mass in the luminous lensing


  We present spatially-resolved X-ray spectroscopy of the luminous lensing
cluster Abell 2390, using observations made with the Chandra observatory. The
temperature of the X-ray gas is shown to rise with increasing radius within the
central ~200 kpc of the cluster, and then remain approximately isothermal, with
kT =11.5^{+1.5}_{-1.6} keV, out to the limits of the observations at r~1.0 Mpc.
The total mass profile determined from the Chandra data has a form in good
agreement with the predictions from numerical simulations. Using the
parameterization of Navarro, Frenk & White (1997), we measure a scale radius
r_s~0.9 Mpc and a concentration parameter c~4. The best-fit X-ray mass model is
in good agreement with independent gravitational lensing results and optical
measurements of the galaxy velocity dispersion in the cluster. The X-ray
gas-to-total-mass ratio rises with increasing radius with f_gas = 21 \pm 10 per
cent at r=0.9 Mpc. The azimuthally-averaged 0.3-7.0 keV surface brightness
profile exhibits a small core radius and a clear `break' at r~500 kpc, where
the slope changes from S_X \approxpropto r^{-1.5} to S_X \approxpropto
r^{-3.6}. The data for the central region of the cluster indicate the presence
of a cooling flow with a mass deposition rate of 200-300 solar masses per year
and an age of 2-3 Gyr.

</DOC>
<DOC>
<DOCNO> 69839 </DOCNO>
Higgs-mass predictions and electroweak precision observables in the


  Higher-order results for electroweak precision observables in the Standard
Model are analyzed in view of the experimental accuracies achievable at the
present and the next generation of colliders, and the indirect prediction of
the Higgs-boson mass from the precision data is discussed. Within the MSSM,
two-loop results for the lightest CP-even Higgs-boson mass are confronted with
the exclusion limits from LEP. Possible precision tests of the MSSM at a future
linear collider are furthermore investigated.

</DOC>
<DOC>
<DOCNO> 10910 </DOCNO>
Perturbative polydispersity: Phase equilibria of near-monodisperse


  The conditions of multi-phase equilibrium are solved for generic polydisperse
systems. The case of multiple polydispersity is treated, where several
properties (e.g. size, charge, shape) simultaneously vary from one particle to
another. By developing a perturbative expansion in the width of the
distribution of constituent species, it is possible to calculate the effects of
polydispersity alone, avoiding difficulties associated with the underlying
many-body problem. Explicit formulae are derived in detail, for the
partitioning of species at coexistence and for the shift of phase boundaries
due to polydispersity. `Convective fractionation' is quantified, whereby one
property (e.g. charge) is partitioned between phases due to a driving force on
another. To demonstrate the ease of use and versatility of the formulae, they
are applied to models of a chemically-polydisperse polymer blend, and of
fluid-fluid coexistence in polydisperse colloid-polymer mixtures. In each case,
the regime of coexistence is shown to be enlarged by polydispersity.

</DOC>
<DOC>
<DOCNO> 85127 </DOCNO>
On the Growth of the Number of Hyperbolic Gravitational Instantons with


  In this paper, we show that the number of hyperbolic gravitational instantons
grows superexponentially with respect to volume. As an application, we show
that the Hartle-Hawking wave function for the universe is infinitely peaked at
a certain closed hyperbolic 3-manifold.

</DOC>
<DOC>
<DOCNO> 119422 </DOCNO>
The Merging System Am 2049-691


  Spectroscopic and photometric observations of the peculiar object AM 2049-691
are presented here. Its systemic velocity is V(GSR) = (10956 +-30) km/s, and
the derived distance (H(0) = 75 km/s/Mpc) results 146 Mpc. A bridge is observed
between two very distinct nuclei whose separation is about 10 kpc, as well as
two tails that emerge from the extremes SW and NE of the main body and extend
up to 41 and 58 kpc respectively. The spectral characteristics of the all
observed zones are typical of H II regions of low excitation. The internal
reddening is quit high, particularly in the NE nucleus. All the derived
equivalent widths of the H(alpha)+[N II] lines indicate enhanced star formation
compared with isolated galaxies, specially in the NE nucleus; the equivalent
width corresponding to the integrated spectrum reflects starburst activity in
the whole object, and is compatible with a merger of two disk galaxies. All the
observed characteristics of AM 2049-691 indicate it is a merger, where a
overabundance of nitrogen is detected in one of the nuclei, which has the most
evolved population and would be the most massive one. The detected total IR
emission is not very high. The integrated total color B - V corresponds to a
Sc-Scd galaxy and its average integrated population is about F7 type.
Indicative B - V colors of the nuclei, corrected for internal absorption, are
in agreement with the spectroscopic results. The central radial velocity
dispersions at the nuclei suggest that the most massive galaxy would be the
progenitor of the SW component. The observed radial velocity curve shows the
presence of two subsystems, each one associated with a different nucleus.

</DOC>
<DOC>
<DOCNO> 68849 </DOCNO>
Exploring CP Violation with $B_c$ Decays


  We point out that the pure ``tree'' decays $B_c^\pm\to D^\pm_s D$ are
particularly well suited to extract the CKM angle $\gamma$ through amplitude
relations. In contrast to conceptually similar strategies using $B^\pm\to K^\pm
D$ or $B_d\to K^{\ast0} D$ decays, the advantage of the $B_c$ approach is that
the corresponding triangles have three sides of comparable length and do not
involve small amplitudes. Decays of the type $B_c^\pm\to D^\pm D$ -- the
$U$-spin counterparts of $B_c^\pm\to D^\pm_s D$ -- can be added to the
analysis, as well as channels, where the $D^\pm_s$- and $D^\pm$-mesons are
replaced by higher resonances.

</DOC>
<DOC>
<DOCNO> 122980 </DOCNO>
Weak lensing study of low mass galaxy groups: implications for Omega_m


  We report on the first measurement of the average mass and mass-to-light
ratio of galaxy groups by analysing the weak lensing signal induced by these
systems. The groups, which have velocity dispersions of 50-400 km/s, have been
selected from the Canadian Network for Observational Cosmology Field Galaxy
Redshift Survey (CNOC2). This survey allows the identification of a large
number of groups with redshifts ranging from z=0.12-0.55, ideal for a weak
lensing analysis of their mass distribution. For our analysis we use a sample
of 50 groups which are selected on the basis of a careful dynamical analysis of
group candidates. We detect a signal at the 99% confidence limit. The best fit
singular isothermal sphere model yields an Einstein radius of 0.72+-0.29". This
corresponds to a velocity dispersion of 274^{+48}_{-59} km/s (using photometric
redshift distributions for the source galaxies), which is in good agreement
with the dynamical estimate. Under the assumption that the light traces the
mass, we find an average mass-to-light ratio of 191+-83 h Msun/Lsun in the
restframe B band. Unlike dynamical estimates, this result is insensitive to
problems associated with determining group membership. After correction of the
observed mass-to-light ratio for luminosity evolution to z=0, we find 254+-110
h Msun/Lsun, lower than what is found for rich clusters. We use the observed
mass-to-light ratio to estimate the matter density of the universe, for which
we find Omega_m=0.19+-0.10 (Omega_Lambda=0), in good agreement with other
recent estimates. For a closed universe, we obtain Omega_m=0.13+-0.07.

</DOC>
<DOC>
<DOCNO> 122619 </DOCNO>
Microslit Nod-shuffle Spectroscopy - a technique for achieving very high


  We describe a new approach to obtaining very high surface densities of
optical spectra in astronomical observations with extremely accurate
subtraction of night sky emission. The observing technique requires that the
telescope is nodded rapidly between targets and adjacent sky positions; object
and sky spectra are recorded on adjacent regions of a low-noise CCD through
charge shuffling. This permits the use of extremely high densities of small
slit apertures (`microslits') since an extended slit is not required for sky
interpolation. The overall multi-object advantage of this technique is as large
as 2.9x that of conventional multi-slit observing for an instrument
configuration which has an underfilled CCD detector and is always >1.5 for high
target densities. The `nod-shuffle' technique has been practically implemented
at the Anglo-Australian Telescope as the `LDSS++ project' and achieves
sky-subtraction accuracies as good as 0.04%, with even better performance
possible. This is a factor of ten better than is routinely achieved with
long-slits. LDSS++ has been used in various observational modes, which we
describe, and for a wide variety of astronomical projects. The nod-shuffle
approach should be of great benefit to most spectroscopic (e.g. long-slit,
fiber, integral field) methods and would allow much deeper spectroscopy on very
large telescopes (10m or greater) than is currently possible. Finally we
discuss the prospects of using nod-shuffle to pursue extremely long
spectroscopic exposures (many days) and of mimicking nod-shuffle observations
with infrared arrays.

</DOC>
<DOC>
<DOCNO> 152491 </DOCNO>
Bosonic M Theory


  We conjecture that there exists a strong coupling limit of bosonic string
theory which is related to the 26 dimensional theory in the same way that 11
dimensional M theory is related to superstring theory. More precisely, we
believe that bosonic string theory is the compactification on a line interval
of a 27 dimensional theory whose low energy limit contains gravity and a
three-form potential. The line interval becomes infinite in the strong coupling
limit, and this may provide a stable ground state of the theory. We discuss
some of the consequences of this conjecture.

</DOC>
<DOC>
<DOCNO> 40057 </DOCNO>
On the masses, branching ratios, and full widths of heavy rho', rho''


  Based on the previous and recent fits of multiple data on the reactions of
e^+e^- annihilation, tau lepton decay, and the reaction K^-p -> pi^+pi^-
Lambda, the magnitude of the branching ratios and total widths of the isovector
rho', rho'', and the isoscalar omega', omega'' resonances are calculated. Some
topics on the spectroscopy of the rho(1450) and omega(1420) states are
discussed.

</DOC>
<DOC>
<DOCNO> 70770 </DOCNO>
Echoes of the fifth dimension?


  In this article we examine the question of whether the highest energy cosmic
ray primaries could be ultra relativistic magnetic monopoles. The analysis is
performed within the framework of large compact dimensions and TeV scale
quantum gravity. Our study indicates that while this hypothesis must be
regarded as highly speculative it cannot be ruled out with present data.

</DOC>
<DOC>
<DOCNO> 100264 </DOCNO>
Minimality of the data in wavelet filters


  Orthogonal wavelets, or wavelet frames, for L^2(R) are associated with
quadrature mirror filters (QMF). The latter constitute a set of complex numbers
which relate the dyadic scaling of functions on R to the Z-translates, and
which satisfy the QMF-axioms. In this paper, we show that generically, the data
in the QMF-systems of wavelets is minimal, in the sense that it cannot be
nontrivially reduced. The minimality property is given a geometric formulation
in the Hilbert space l^2(Z), and it is then shown that minimality corresponds
to irreducibility of a wavelet representation of the algebra O_2; and so our
result is that this family of representations of O_2 on the Hilbert space
l^2(Z) is irreducible for a generic set of values of the parameters which label
the wavelet representations.

</DOC>
<DOC>
<DOCNO> 122125 </DOCNO>
ISO continuum observations of quasars at z=1-4 I.Spectral energy


  Eight luminous quasars with $ -30 < M_B < -27$ at z = 1.4 - 3.7 have been
observed in the mid- and far-infrared using ISO. All the quasars have been
detected in the mid-infrared bands of ISOCAM, while no far-infrared detections
have been made with ISOPHOT. Supplementing ISO observations with photometry in
the optical and near-infrared made from the ground mostly within 17 months
after the ISO observations, SEDs (Spectral Energy Distributions) from the UV to
far-infrared have been obtained. SEDs (Spectral Energy Distributions) from the
UV to far-infrared have been obtained while supplementing ISO observations with
photometry in the optical and near-infrared made from the ground within 17
months. The SEDs are compared with the MED (Mean spectral Energy Distributions)
of low-redshift quasars with $-27 < M_B < -22$. It is shown that our
far-infrared observations were limited by confusion noise due to crowded
sources.

</DOC>
<DOC>
<DOCNO> 40292 </DOCNO>
Beam Test Results of the BTeV Silicon Pixel Detector


  The results of the BTeV silicon pixel detector beam test carried out at
Fermilab in 1999-2000 are reported. The pixel detector spatial resolution has
been studied as a function of track inclination, sensor bias, and readout
threshold.

</DOC>
<DOC>
<DOCNO> 13226 </DOCNO>
Spontaneous alloying in binary metal microclusters - A molecular


  Microcanonical molecular dynamics study of the spontaneous alloying(SA),
which is a manifestation of fast atomic diffusion in a nano-sized metal
cluster, is done in terms of a simple two dimensional binary Morse model.
Important features observed by Yasuda and Mori are well reproduced in our
simulation. The temperature dependence and size dependence of the SA phenomena
are extensively explored by examining long time dynamics. The dominant role of
negative heat of solution in completing the SA is also discussed. We point out
that a presence of melting surface induces the diffusion of core atoms even if
they are solid-like. In other words, the {\it surface melting} at substantially
low temperature plays a key role in attaining the SA.

</DOC>
<DOC>
<DOCNO> 101171 </DOCNO>
Riemann-Roch Theorem, Stability and New Zeta Functions for Number Fields


  With the help of Prof. Deninger, we are able to find the precise references
on semi-stable lattices now. So I add them here.

</DOC>
<DOC>
<DOCNO> 121646 </DOCNO>
A 2.14 ms Candidate Optical Pulsar in SN1987A


  We have monitored Supernova 1987A in optical/near-infrared bands from a few
weeks following its birth until the present time in order to search for a
pulsar remnant. We have found an apparent pattern of emission near the
frequency of 467.5 Hz - a 2.14 ms pulsar candidate, first detected in data
taken on the remnant at the Las Campanas Observatory (LCO) 2.5-m Dupont
telescope during 14-16 Feb. 1992 UT. We detected further signals near the 2.14
ms period on numerous occasions over the next four years in data taken with a
variety of telescopes, data systems and detectors, at a number of ground- and
space-based observatories. The sequence of detections of this signal from Feb.
`92 through August `93, prior to its apparent subsequent fading, is highly
improbable (< 1.e-10) for any noise source). We also find evidence for
modulation of the 2.14 ms period with a ~1,000 s period which, when taken with
the high spindown of the source (2-3e-10 Hz/s), is consistent with precession
and spindown via gravitational radiation of a neutron star with a
non-axisymmetric oblateness of ~1e-6, and an implied gravitational luminosity
exceeding that of the Crab Nebula pulsar by an order of magnitude.

</DOC>
<DOC>
<DOCNO> 101009 </DOCNO>
Positivity and complexity of ideal sheaves


  The problem of bounding the "complexity" of a polynomial ideal in terms of
the degrees of its generators has attracted considerable interest, brought into
focus by the influential survey of Bayer and Mumford. The present paper
examines some of these results and questions from a geometric perspective.
Specifically, motivated by work of Paoletti we introduce an invariant s(I) that
measures the "positivity" of an ideal sheaf I. Degree bounds on generators of I
yield bounds on this s-invariant, but s(I) may be small even when the degrees
of its generators are large. We prove that s(I) computes the asymptotic
Castelnuovo-Mumford regularity of large powers of I, and bounds the asymptotic
behavior of several other measures of complexity. We also show that this
s-invariant behaves very well with respect to natural geometric and algebraic
operations, which leads to considerably simplified constructions of varieties
with irrational asymptotic regularity. The main tools are intersection theory
and vanishing theorems.

</DOC>
<DOC>
<DOCNO> 102447 </DOCNO>
Strict Deformation Quantization for Actions of a Class of Symplectic Lie


  We present explicit universal strict deformation quantization formulae for
actions of Iwasawa subgroups AN of SU(1,n). This answers a question raised by
Rieffel.

</DOC>
<DOC>
<DOCNO> 150585 </DOCNO>
Two-Time Physics with gravitational and gauge field backgrounds


  It is shown that all possible gravitational, gauge and other interactions
experienced by particles in ordinary d-dimensions (one-time) can be described
in the language of two-time physics in a spacetime with d+2 dimensions. This is
obtained by generalizing the worldline formulation of two-time physics by
including background fields. A given two-time model, with a fixed set of
background fields, can be gauged fixed from d+2 dimensions to (d-1) +1
dimensions to produce diverse one-time dynamical models, all of which are
dually related to each other under the underlying gauge symmetry of the unified
two-time theory. To satisfy the gauge symmetry of the two-time theory the
background fields must obey certain coupled differential equations that are
generally covariant and gauge invariant in the target d+2 dimensional
spacetime. The gravitational background obeys a null homothety condition while
the gauge field obeys a differential equation that generalizes a similar
equation derived by Dirac in 1936. Explicit solutions to these coupled
equations show that the usual gravitational, gauge, and other interactions in d
dimensions may be viewed as embedded in the higher d+2 dimensional space, thus
displaying higher spacetime symmetries that otherwise remain hidden.

</DOC>
<DOC>
<DOCNO> 80784 </DOCNO>
On the Equivalence of Noncommutative Models in Various Dimensions and


  Here we construct a map from the algebra of fields in two-dimensional
noncommutative of U(1) Yang-Mills fields interacting with Kaluza-Klein scalars
to a D-dimensional one, as a solution in the two-dimensional model. This proves
the equivalence of noncommutative models in various (even) dimensions.
Physically this map describes condensation of D1-branes.

</DOC>
<DOC>
<DOCNO> 69720 </DOCNO>
Radiative corrections to e+e- --> WW --> 4f with RACOONWW


  RACOONWW is the first Monte Carlo generator for e+e- --> WW --> 4f(+gamma)
that includes the electroweak O(alpha) radiative corrections in the double-pole
approximation completely. Some numerical results for LEP2 energies are
discussed, and the predictions for the total W-pair cross section are
confronted with LEP2 data.

</DOC>
<DOC>
<DOCNO> 11713 </DOCNO>
Overcritical states of a superconductor strip in a magnetic environment


  A current-carrying superconducting strip partly penetrated by magnetic flux
and surrounded by a bulk magnet of high permeability is considered. Two types
of samples are studied: those with critical current controlled by an edge
barrier dominating over the pinning, and those with high pinning-mediated
critical current masking the edge barrier.It is shown for both cases that the
current distribution in a central flux-free part of the strip is strongly
affected by the actual shape of the magnetic surroundings. Explicit analytical
solutions for the sheet current and self-field distributions are obtained which
show that, depending on the geometry, the effect may suppress the total
loss-free transport current of the strip or enhance it by orders of magnitude.
The effect depends strongly on the shape of the magnet and its distance to the
superconductor but only weakly on the magnetic permeability.

</DOC>
<DOC>
<DOCNO> 8137 </DOCNO>
A numerical method for detecting incommensurate correlations in the


  We study two Heisenberg spin-1/2 chains coupled by a frustrating ``zigzag''
interaction. We are particularly interested in the regime of weak interchain
coupling, which is difficult to analyse by either numerical or analytical
methods. Previous density matrix renormalisation group (DMRG) studies of the
isotropic model with open boundary conditions and sizeable interchain coupling
have established the presence of incommensurate correlations and of a spectral
gap. By using twisted boundary conditions with arbitrary twist angle, we are
able to determine the incommensurabilities both in the isotropic case and in
the presence of an exchange anisotropy by means of exact diagonalisation of
relatively short finite chains of up to 24 sites. Using twisted boundary
conditions results in a very smooth dependence of the incommensurabilities on
system size, which makes the extrapolation to infinite systems significantly
easier than for open or periodic chains.

</DOC>
<DOC>
<DOCNO> 122815 </DOCNO>
The BAIKAL neutrino project: status report


  We review the present status of the Baikal Neutrino Project and present
preliminary results of a search for upward going atmospheric neutrinos, WIMPs
and magnetic monopoles obtained with the detector NT-2000 during 1998. Also the
results of a search for very high energy neutrinos with partially completed
detector in 1996 are presented.

</DOC>
<DOC>
<DOCNO> 123003 </DOCNO>
Accretion onto nearby supermassive black holes: Chandra constraints on


  Chandra observations of low-luminosity supermassive black holes in nearby
elliptical galaxies provide tight limits on both their nuclear luminosities and
on their Bondi accretion rates. We examine Chandra constraints on NGC 6166, the
dominant galaxy in the cluster Abell 2199, which hosts a \sim 10^9 \Msun black
hole. We measure a nuclear X-ray luminosity L_{x} \sim 10^{40} erg/s and show
that the density and temperature profiles of the hot interstellar medium imply
a Bondi accretion rate of Mdot_{Bondi} \sim 3 10^{-2} Msun/yr. This accretion
rate predicts a nuclear luminosity of \sim 10^{44} erg/s for a canonical
radiative efficiency of 10%. Unless the Bondi estimate is inappropriate and/or
the accretion rate onto the black hole is significantly reduced, the observed
nuclear flux constrains the radiative efficiency of the accretion flow to be
\eta \sim 10^{-5}. We show that low-radiative efficiency accretion flows with
radial density profiles \rho \approxpropto r^{-3/2} (and not significantly
flatter) can explain the observed nuclear X-ray luminosity but that the power
output from the jets in NGC 6166 is also important to the energetics of the
system.

</DOC>
<DOC>
<DOCNO> 118865 </DOCNO>
Possible evidence for the disk origin for the powering of jets in Sgr A*


  The predicted radio flux for nearby ellipticals by the canonical
ADAF(advection-dominated accretion flow) model is well above the observations.
If the mass accretion rate favored by the numerical simulation were adopted,
the ADAF model would also significantly overpredict the radio flux of Sgr A*.
On the observational side, strong evidence for the existence of jets in Sgr
A$^*$ and these ellipticals has been obtained. Based on these facts, we propose
a truncated ADAF model for these sources. We assume that the accretion disk is
truncated at a certain radius within which a jet forms by extracting the energy
of the disk therefore the radio flux is greatly suppressed due to the radiative
truncation of the disk and the fits to the observational data are excellent.
For example, for Sgr A*, the model fits the spectrum very well from radio
including the ``excess'' below the break frequency to hard X-ray under a high
accretion rate near the simulation value; for M87, the predicted upper limit of
the jet location is 24 $R_g$, in excellent agreement with the observational
result of < 30 $R_g$. The success of the model supplies a possible piece of
evidence for the disk rather than the hole origin for the powering of jets.

</DOC>
<DOC>
<DOCNO> 84576 </DOCNO>
Precanonical Perspective in Quantum Gravity


  Quantization of general relativity in metric variables using ``precanonical''
quantization based on the De Donder-Weyl covariant Hamiltonian formulation is
outlined. Elements of classical geometry needed to formulate the (Dirac-like)
wave equation emerge from a self-consistency with the underlying quantum
dynamics of the metric. In this sense the formulation can be viewed as
independent from an arbitrarily fixed background.

</DOC>
<DOC>
<DOCNO> 12844 </DOCNO>
Magnetization Plateaux in Quasi-One-Dimensional Strongly Correlated


  This is a short review of recent theoretical work on magnetization plateaux
in one-dimensional strongly correlated electron systems, i.e. in spin chains,
spin ladders or more generally, Hubbard chains and ladders.

</DOC>
<DOC>
<DOCNO> 70779 </DOCNO>
A Study of the Thermodynamical Properties of a Hot, Dense Hadron Gas


  We investigate the equilibration and the equation of state of a hot hadron
gas at finite baryon density using an event generator which is designed to
approximately satisfy detailed balance at finite temperatures and finite baryon
densities of the hadronic scale (80 MeV < T < 170 MeV and 0.157 fm^-3 < n_B <
0.315 fm^-3). Molecular-dynamical simulations were performed for a system of
hadrons in a box with periodic boundary conditions. Starting from an initial
state composed of only nucleons with a uniform phase-space distribution, the
evolution takes place through interactions such as collisions, productions and
absorptions. The system approaches a stationary state of baryons, mesons and
their resonances, which is characterized by the value of the exponent in the
energy distribution common to the different particles, i.e., the temperature.
After the equilibration, thermodynamic quantities, such as the energy density,
particle density, entropy and pressure are calculated. Above T - m_pi, the
obtained equation of state exhibits a significant deviation from the naive
mixed free gas model. Large values of the entropy per baryon are also notable.
In our system, the excitation of heavy baryon resonances and meson production
are enhanced simultaneously, and the increase of the temperature becomes
moderate, but a Hagedorn-type artificial temperature saturation does not occur.
The pressure exhibits a linear dependence on the energy density.

</DOC>
<DOC>
<DOCNO> 102089 </DOCNO>
Remarks on hereditarily indecomposable continua


  We recall a characterization of hereditary indecomposability originally
obtained by Krasinkiewicz and Minc, and show how it may be used to give unified
constructions of various hereditarily indecomposable continua. In particular we
answer a question asked by Mackowiak and Tymchatyn by showing that any
continuum of arbitrary weight is a weakly confluent image of a hereditarily
indecomposable continuum of the same weight.
  We present two methods of constructing these preimages: (a) by
model-theoretic means, using the compactness and completeness theorems from
first-order logic to derive these results for continua of uncountable weight
from their metric counterparts; and (b) by constructing essential mappings from
hereditarily indecomposable continua onto Tychonoff cubes.
  We finish by reviving an argument due to Kelley about hyperspaces of
hereditarily indecomposable continua and show how it leads to a point-set
argument that reduces Brouwer's Fixed-point theorem to its three-dimensional
version.

</DOC>
<DOC>
<DOCNO> 102456 </DOCNO>
The minimal entropy problem for 3-manifolds with zero simplicial volume


  We consider the minimal entropy problem, namely the question of whether there
exists a smooth metric of minimal entropy, for certain classes of 3-manifolds.
Among other resulsts, we show that if M is a closed, orientable, geometrizable
3-manifold with zero simplicial volume, then the minimal entropy can be solved
for M if and only if M admits a metric modelled on 4 of the 8 standard
3-dimensional geometries, namely $S^3$, $S^2\times R$, $E^3$, or Nil.

</DOC>
<DOC>
<DOCNO> 119369 </DOCNO>
Extra-Solar Planets


  The discovery of the first extra-solar planet surrounding a main-sequence
star was announced in 1995, based on very precise radial velocity (Doppler)
measurements. A total of 34 such planets were known by the end of March 2000,
and their numbers are growing steadily. The newly-discovered systems confirm
some of the features predicted by standard theories of star and planet
formation, but systems with massive planets having very small orbital radii and
large eccentricities are common and were generally unexpected. Other techniques
being used to search for planetary signatures include accurate measurement of
positional (astrometric) displacements, gravitational microlensing, and pulsar
timing, the latter resulting in the detection of the first planetary mass
bodies beyond our Solar System in 1992. The transit of a planet across the face
of the host star provides significant physical diagnostics, and the first such
detection was announced in 1999. Protoplanetary disks, which represent an
important evolutionary stage for understanding planet formation, are being
imaged from space. In contrast, direct imaging of extra-solar planets
represents an enormous challenge. Long-term efforts are directed towards
infrared space interferometry, the detection of Earth-mass planets, and
measurement of their spectral characteristics. Theoretical atmospheric models
provide predictions of planetary temperatures, radii, albedos, chemical
condensates, and spectral features as a function of mass, composition and
distance from the host star. Efforts to characterise planets occupying the
`habitable zone', in which liquid water may be present, and indicators of the
presence of life, are advancing quantitatively.

</DOC>
<DOC>
<DOCNO> 120285 </DOCNO>
Hard X-ray Emission and the Ionizing Source in LINERs


  We report X-ray fluxes in the 2--10 keV band from LINERs (low-ionization
nuclear emission-line regions) and low-luminosity Seyfert galaxies obtained
with the ASCA satellite. Observed X-ray luminosities are in the range between
4e39 and 5e41 ergs/s, which are significantly smaller than that of the
``classical'' low-luminosity Seyfert 1 galaxy NGC 4051. We found that X-ray
luminosities in 2--10 keV of LINERs with broad Halpha emission in their optical
spectra (LINER 1s) are proportional to their Halpha luminosities. This
correlation strongly supports the hypothesis that the dominant ionizing source
in LINER 1s is photoionization by hard photons from low-luminosity AGNs. On the
other hand, the X-ray luminosities of most LINERs without broad Halpha emission
(LINER 2s) in our sample are lower than LINER 1s at a given Halpha luminosity.
The observed X-ray luminosities in these objects are insufficient to power
their Halpha luminosities, suggesting that their primary ionizing source is
other than an AGN, or that an AGN, if present, is obscured even at energies
above 2 keV.

</DOC>
<DOC>
<DOCNO> 150381 </DOCNO>
Anomalous U(1) Vortices and The Dilaton


  The role of the (dynamical) dilaton in the vortices associated with the
spontaneous breaking of an anomalous U(1) from heterotic string theory is
examined. We demonstrate how the anomaly (and the coupling to the
dilaton/axion) can appear in the Lagrangian and associated field equations as a
controlled perturbation about the standard Nielsen-Olesen equations. In such a
picture, the additional field equation for the dilaton becomes a series of
corrections to a constant dilaton vev as the anomaly is turned on. In
particular we find that even the first nontrivial correction to a constant
dilaton generically leads to a (positive) logarithmic divergence of the
heterotic dilaton near the vortex core. Since the dilaton field governs the
strength of quantum fluctuations in string theory, this runaway behaviour
implies that anomalous U(1) vortices in string theory are intrinsically quantum
mechanical objects.

</DOC>
<DOC>
<DOCNO> 9314 </DOCNO>
Spin chirality induced by the Dzyaloshinskii-Moriya interaction and the


  We discuss the influence of the Dzyaloshinskii-Moriya (DM) interaction in the
Heizenberg spin chain model for the observables in the polarized neutron
scattering experiments. We show that different choices of the parameters of DM
interaction may leave the spectrum of the problem unchanged, while the
observable spin-spin correlation functions may differ qualitatively.
Particularly, for the uniform DM interaction one has the incommensurate
fluctuations and polarization-dependent neutron scattering in the paramagnetic
phase. We sketch the possible generalization of our treatment to higher
dimensions.

</DOC>
<DOC>
<DOCNO> 123265 </DOCNO>
Large scale dynamos with helicity loss through boundaries


  Dynamo action is investigated in simulations of locally isotropic and
homogeneous turbulence in a slab between open boundaries. It is found that a
`pseudo-vacuum' boundary condition (where the field is vertical) leads to
strong helicity fluxes which significantly reduce the amplitude of the
resulting large scale field. On the other hand, if there is a conducting halo
outside the dynamo-active region the large scale field amplitude can reach
larger values, but the time scale after which this field is reached increases
linearly with the magnetic Reynolds number. In both cases most of the helicity
flux is found to occur on large scales. From the variety of models considered
we conclude that open boundaries tend to lower the saturation field strength
compared to the case with periodic boundaries. The rate at which this lower
saturation field strength is attained is roughly independent of the strength of
the turbulence and of the boundary conditions. For dynamos with less helicity,
however, significant field strengths could be reached in a shorter time.

</DOC>
<DOC>
<DOCNO> 170110 </DOCNO>
Quantum Optimization


  We present a quantum algorithm for combinatorial optimization using the cost
structure of the search states. Its behavior is illustrated for overconstrained
satisfiability and asymmetric traveling salesman problems. Simulations with
randomly generated problem instances show each step of the algorithm shifts
amplitude preferentially towards lower cost states, thereby concentrating
amplitudes into low-cost states, on average. These results are compared with
conventional heuristics for these problems.

</DOC>
<DOC>
<DOCNO> 151941 </DOCNO>
An Observation on Finite Groups and WZW Modular Invariants


  In this short note, inspired by much recent activity centered around attempts
to formulate various correspondences between the classification of affine SU(k)
WZW modular-invariant partition functions and that of discrete finite subgroups
of SU(k), we present a small and perhaps interesting observation in this light.
In particular we show how the groups generated by the permutation of the terms
in the exceptional Affine SU(2)-WZW invariants encode the corresponding
exceptional SU(2) subgroups.

</DOC>
<DOC>
<DOCNO> 117756 </DOCNO>
Evaporation and Condensation Processes of Giant Molecular Clouds in a


  2d hydrodynamical simulations are performed to examine the evaporation and
condensation processes of giant molecular clouds in the hot phase of the
interstellar medium. The evolution of cold and dense clouds is calculated in
the subsonic stream of a hot tenuous plasma. Our code includes self-gravity,
heating and cooling processes and heat conduction by electrons. Significant
differences occur between simulations with and without heat conduction.

</DOC>
<DOC>
<DOCNO> 116326 </DOCNO>
Averages of static electric and magnetic fields over a spherical region:


  Submitted to "Notes and Discussions" in American Journal of Physics.

</DOC>
<DOC>
<DOCNO> 151247 </DOCNO>
Large N Expansion From Fuzzy AdS_2


  We study the quantum analogue of primary fields and their descendants on
fuzzy AdS_2, proposed in hep-th/0004072. Three-point vertices are calculated
and shown to exhibit the conventional 1/N expansion as well as nonperturtive
effects in large N, thus providing a strong consistency check of the fuzzy
AdS_2 model. A few new physical motivations for this model are also presented.

</DOC>
<DOC>
<DOCNO> 151935 </DOCNO>
A Note on the Non-Commutative Wess-Zumino Model


  We show that the noncommutative Wess-Zumino (NCWZ) Lagrangian with
permutation terms in the interaction parts is renormalizable at one-loop level
by only a wave function renormalization. When the non-commutativity vanishes,
the logarithmic divergence of the wave function renormalization of the NCWZ
theory is the same as that of the commutative one. Next the algebras of
noncommutative field theories (NCFT's) are studied. From Neother currents, the
field representation for the generators of NCFT's is extracted. Then based on
this representation, the commutation relations between the generators are
calculated for NCFT's. The symmetry properties of NCFT's inferred from these
commutation relations are discussed and compared with those of the commutative
ones.

</DOC>
<DOC>
<DOCNO> 100283 </DOCNO>
New Numerical Algorithm for Modeling of Boson-Fermion Stars in Dilatonic


  We investigate numerically a models of the static spherically symmetric
boson-fermion stars in scalar-tensor theory of gravity with massive dilaton
field. The proper mathematical model of such stars is interpreted as a
nonlinear two-parametric eigenvalue problem with unknown internal boundary. We
employ the Continuous Analogue of Newton Method (CANM) which leads on each
iteration to two separate linear boundary value problems with different
dimensions inside and outside the star, respectively. Along with them a
nonlinear algebraic system for the spectral parameters - radius of the star
$R_{s}$ and quantity $\Omega $ is solved also.
  In this way we obtain the behaviour of the basic geometric quantities and
functions describing dilaton field and matter fields which build the star.

</DOC>
<DOC>
<DOCNO> 170500 </DOCNO>
Vacuum-Stimulated Raman Scattering based on Adiabatic Passage in a


  We report on the first observation of stimulated Raman scattering from a
Lambda-type three-level atom, where the stimulation is realized by the vacuum
field of a high-finesse optical cavity. The scheme produces one intracavity
photon by means of an adiabatic passage technique based on a counter-intuitive
interaction sequence between pump laser and cavity field. This photon leaves
the cavity through the less-reflecting mirror. The emission rate shows a
characteristic dependence on the cavity and pump detuning, and the observed
spectra have a sub-natural linewidth. The results are in excellent agreement
with numerical simulations.

</DOC>
<DOC>
<DOCNO> 118067 </DOCNO>
Aluminum Abundances, Deep Mixing and the Blue-Tail Second-Parameter


  We explore the relatiohsip between deep mixing on the red-giant branch and
the second parameter that gives rise to the extended blue tail seen on the
horizontal branch of the globular cluster M 13. We use the [Al/Fe] values of 96
RGB stars and the [Na/Fe] values of 119 RGB stars in M 13 to follow the
evolution of mixing in this cluster. The data are compared to an
"instantaneous" mixing algorithm to predict the effects of deep mixing on the
HB morphology. In addition, we present new data for six giants in the cluster M
3 and three in M 13. Our final results are consistent with deep mixing as a
blue-tail second parameter. We also examine the question of overproducing
sodium during deep mixing and suggest ways around this problem and
observational tests that center around the s-process elements Sr, Y and Zr.

</DOC>
<DOC>
<DOCNO> 169915 </DOCNO>
Quantum dynamics and statistics of two coupled down-conversion processes


  In the framework of Heisenberg-Langevin theory the dynamical and statistical
effects arising from the linear interaction of two nondegenerate
down-conversion processes are investigated. Using the strong-pumping
approximation the analytical solution of equations of motion is calculated. The
phenomena reminiscent of Zeno and anti-Zeno effects are examined. The
possibility of phase-controlled and mismatch-controlled switching is
illustrated.

</DOC>
<DOC>
<DOCNO> 118484 </DOCNO>
The recent star formation history of the Hipparcos solar neighbourhood


  We use data from the Hipparcos catalogue to construct colour-magnitude
diagrams for the solar neighbourhood, which are then treated using advanced
Bayesian analysis techniques to derive the star formation history, $SFR(t)$, of
this region over the last 3 Gyr. The method we use allows the recovery of the
underlying $SFR(t)$ without the need of assuming any {\it a priori} structure
or condition on $SFR(t)$, and hence yields a highly objective result. The
remarkable accuracy of the data permits the reconstruction of the local
$SFR(t)$ with an unprecedented time resolution of $\approx 50 $ Myr. A $SFR(t)$
having an oscillatory component of period $\approx 0.5$ Gyr is found,
superimposed on a small level of constant star formation activity. Problems
arising from the non-uniform selection function of the Hipparcos satellite are
discussed and treated. Detailed statistical tests are then performed on the
results, which confirm the inferred $SFR(t)$ to be compatible with the observed
distribution of stars.

</DOC>
<DOC>
<DOCNO> 151657 </DOCNO>
Dipoles, Twists and Noncommutative Gauge Theory


  T-duality of gauge theories on a noncommutative $T^d$ can be extended to
include fields with twisted boundary conditions. The resulting T-dual theories
contain novel nonlocal fields. These fields represent dipoles of constant
magnitude. Several unique properties of field theories on noncommutative spaces
have simpler counterparts in the dipole-theories.

</DOC>
<DOC>
<DOCNO> 99924 </DOCNO>
On Mostow rigidity for variable negative curvature


  We prove a finiteness theorem for the class of complete finite volume
Riemannian manifolds with pinched negative sectional curvature, fixed
fundamental group, and of dimension $>2$. One of the key ingredients is that
the fundamental group of such a manifold does not admit a small nontrivial
action on an $R$-tree.

</DOC>
<DOC>
<DOCNO> 120715 </DOCNO>
Scaling and fluctuations in galaxy distribution: two tests to probe


  We present a brief introduction to the statistical properties of systems with
large fluctuations. We point out that for such systems the relevant statistical
quantities are scaling exponents and the nature of fluctuations is completely
different from the one belonging to system with small fluctuations. We then
propose two test to be performed on galaxy counts data as a function of
apparent magnitude, which may clarify in a direct way the nature of the large
scale galaxy clustering

</DOC>
<DOC>
<DOCNO> 151052 </DOCNO>
Adding Matter to Poincare Invariant Branes


  A solution to the cosmological constant problem has been proposed in which
our universe is a 3-brane in a 5-dimensional spacetime. With a bulk scalar, the
field equations admit a Poincare invariant brane solution regardless of the
value of the cosmological constant (tension) on the brane. However, the
solution does not include matter in the brane. We find new exact static
solutions with matter density and pressure in the brane. We study small
perturbations about these solutions. None seem consistent with observational
cosmology. As a byproduct we find a class of new matterless static solutions
and a non-static solution which, curiously, requires the string value for the
dilaton coupling.

</DOC>
<DOC>
<DOCNO> 100407 </DOCNO>
Kazhdan-Lusztig polynomials for 321-hexagon-avoiding permutations


  We give a combinatorial formula for the Kazhdan-Lusztig polynomials $P_{x,w}$
in the symmetric group when $w$ is a 321-hexagon-avoiding permutation. Our
formula, which depends on a combinatorial framework developed by Deodhar, can
be expressed in terms of a simple statistic on all subexpressions of any fixed
reduced expression for $w$. We also show that $w$ being 321-hexagon-avoiding is
equivalent to several other conditions, such as the Bott-Samelson resolution of
the Schubert variety $X_w$ being small. We conclude with a simple method for
completely determining the singular locus of $X_w$ when $w$ is
321-hexagon-avoiding.

</DOC>
<DOC>
<DOCNO> 8177 </DOCNO>
Probing the basins of attraction of a recurrent neural network


  A recurrent neural network is considered that can retrieve a collection of
patterns, as well as slightly perturbed versions of this `pure' set of patterns
via fixed points of its dynamics. By replacing the set of dynamical
constraints, i.e., the fixed point equations, by an extended collection of
fixed-point-like equations, analytical expressions are found for the weights
w_ij(b) of the net, which depend on a certain parameter b. This so-called basin
parameter b is such that for b=0 there are, a priori, no perturbed patterns to
be recognized by the net. It is shown by a numerical study, via probing sets,
that a net constructed to recognize perturbed patterns, i.e., with values of
the connections w_ij(b) with b unequal zero, possesses larger basins of
attraction than a net made with the help of a pure set of patterns, i.e., with
connections w_ij(b=0). The mathematical results obtained can, in principle, be
realized by an actual, biological neural net.

</DOC>
<DOC>
<DOCNO> 69719 </DOCNO>
SUSY Search in TeV Scale Polarized Photon-Proton Collisions


  Production of supersymmetric particles in TeV scale polarized photon-proton
collisions is discussed. Polarizations of both photon and proton beams are
considered. Associated productions of squark-chargino and squark-gluino, and
production of squark pairs have been examined. Although the cross sections for
different initial beam polarizations do not differ much, the polarization
asymmetry is sensitive to the sparticle mass. We conclude that the capacity of
future linac-ring type TeV scale photon-proton colliders is quite promising in
the search for SUSY particles.

</DOC>
<DOC>
<DOCNO> 71386 </DOCNO>
Clocks, computers, black holes, spacetime foam, and holographic


  What do simple clocks, simple computers, black holes, space-time foam, and
holographic principle have in common? I will show that the physics behind them
is inter-related, linking together our concepts of information, gravity, and
quantum uncertainty. Thus, the physics that sets the limits to computation and
clock precision also yields Hawking radiation of black holes and the
holographic principle. Moreover, the latter two strongly imply that space-time
undergoes much larger quantum fluctuations than what the folklore suggests ---
large enough to be detected with modern gravitational-wave interferometers
through future refinements.

</DOC>
<DOC>
<DOCNO> 67729 </DOCNO>
On the azimuthal asymmetries in DIS


  Using the recent experimental data on the left right asymmetry in
fragmentation of transversely polarized quarks and the theoretical calculation
of the proton transversity distribution in the effective chiral quark soliton
model we explain the azimuthal asymmetries in semi-inclusive hadron production
on longitudinal (HERMES) and transversely (SMC) polarized targets with no free
parameters. On this basis we state that the proton transversity distribution
could be successfully measured in future DIS experiments with longitudinally
polarized target.

</DOC>
<DOC>
<DOCNO> 170389 </DOCNO>
Experimental requirements for quantum communication complexity protocols


  I present a simple two-party quantum communication complexity protocol with
higher success rate than the best possible classical protocol for the same
task. The quantum protocol is shown to be equivalent to a quantum non-locality
test, except that it is not necessary to close the locality loophole. I derive
bounds for the detector efficiency and background count rates necessary for an
experimental implementation and show that they are close to what can be
currently achieved using ion trap technology. I also analyze the requirements
for a three-party protocol and show that they are less demanding than those for
the two-party protocol. The results can be interpreted as sufficient
experimental conditions for quantum non-locality tests using two or three
entangled qubits.

</DOC>
<DOC>
<DOCNO> 10419 </DOCNO>
Observation of Superfluid Flow in a Bose-Einstein Condensed Gas


  We have studied the hydrodynamic flow in a Bose-Einstein condensate stirred
by a macroscopic object, a blue detuned laser beam, using nondestructive {\em
in situ} phase contrast imaging. A critical velocity for the onset of a
pressure gradient has been observed, and shown to be density dependent. The
technique has been compared to a calorimetric method used previously to measure
the heating induced by the motion of the laser beam.

</DOC>
<DOC>
<DOCNO> 68593 </DOCNO>
An Analysis of the Asymptotic Limit of Gluon Shadowing


  We examine the gluon distributions in nuclei in the asymptotic region defined
by $Q^2 \to \infty$, $x \to 0$. An analysis using the Double Asymptotic Scaling
variables of Ball and Forte is proposed. New scaling relations are predicted
which can help disentangling the different mechanisms of low $x$ perturbative
QCD evolution in nuclei.

</DOC>
<DOC>
<DOCNO> 101668 </DOCNO>
Homogeneous hyper-Hermitian metrics which are conformally hyper-K\"ahler


  Let $g$ be a hyper-Hermitian metric on a simply connected hypercomplex
four-manifold $M$. We show that when the isometry group $I(M,g)$ contains a
subgroup acting simply transitively on $M$ by hypercomplex isometries then the
metric $g$ is conformal to a hyper-K\"ahler metric. We describe explicitely the
corresponding hyper-K\"ahler metrics and it follows that, in four dimensions,
these are the only hyper-K\"ahler metrics containing a homogeneous metric in
its conformal class.

</DOC>
<DOC>
<DOCNO> 122390 </DOCNO>
Lithium-Beryllium-Boron and Oxygen in the early Galaxy


  Oxygen is a much better evolutionary index than iron to follow the history of
Lithium-Beryllium-Boron (LiBeB) since it is the main producer of these light
elements at least in the early Galaxy. The O-Fe relation is crucial to the
determination of the exact physical process responsible for the LiBeB
production. Calculated nucleosynthetic yields of massive stars, estimates of
the energy cost of Be production, and above all recent observations reported in
this meeting seem to favor a mechanism in which fast nuclei enriched into He, C
and O arising from supernovae are accelerated in superbubbles and fragment on H
and He in the interstellar medium.

</DOC>
<DOC>
<DOCNO> 152215 </DOCNO>
Singular Calabi-Yau Manifolds and ADE Classification of CFTs


  We study superstring propagations on the Calabi-Yau manifold which develops
an isolated ADE singularity. This theory has been conjectured to have a
holographic dual description in terms of N=2 Landau-Ginzburg theory and
Liouville theory. If the Landau-Ginzburg description precisely reflects the
information of ADE singularity, the Landau-Ginzburg model of $D_4,E_6,E_8$ and
Gepner model of $A_2\otimes A_2, A_2\otimes A_3, A_2\otimes A_4$ should give
the same result. We compute the elements of $D_4,E_6,E_8$ modular invariants
for the singular Calabi-Yau compactification in terms of the spectral flow
invariant orbits of the tensor product theories with the theta function which
encodes the momentum mode of the Liouville theory. Furthermore we find the
interesting identity among characters in minimal models at different levels. We
give the complete proof for the identity.

</DOC>
<DOC>
<DOCNO> 117171 </DOCNO>
Auto-Correlation Functions and Solar Cycle Predictability


  Starting from the traditional definition of auto-correlation function we can
introduce a new quantity, based on the wavelet formalism, called local wavelet
auto-correlation function, which contains more information about the
correlation properties on a given signal on different scales. The application
of this formalism to the temporal variations of solar activity, from the
monthly time series of sunspot numbers, allows to derive some interesting
information about the correlation properties of different periodicities present
in the signal and in particular the correlation characteristics of the main 11
years Schwabe cycle. The scale selectivity, allowed by the local wavelet
auto-correlation function, can give interesting information about the range of
reliable predictions reachable through deterministic predictive models.

</DOC>
<DOC>
<DOCNO> 122342 </DOCNO>
Evidence for Galaxy Formation at High Redshift


  We have shown previously that galaxy counts from the UV to the near-IR are
well-fitted by simple evolutionary models where the space density of galaxies
remains constant with look-back time while the star-formation rate rises
exponentially. We now extend these results, first by using data from the
Herschel Deep Field to show that these same models give detailed fits to the
faint galaxy r-i:b-r colour-colour diagram. We then use these models to predict
the number counts of high redshift galaxies detected by the Lyman break
technique. At z~3 there is almost exact agreement between ou r prediction and
the data, suggesting that the space density of galaxies at z~3 may be close to
its local value. At z~4 the space density of bright galaxies remains unchanged;
however, the space density of dwarf galaxies is significantly lower than it is
locally, suggesting that we have detected an epoch of dwarf galaxy formation at
z~4. Finally, significant numbers of Lyman-break galaxy candidates are also
detected at z~6 in the Hubble and Herschel Deep Fields; taking this observation
together with a number of recent detections of spectroscopically confirmed z~6
galaxies suggests that the space density of bright galaxies at z~6 remains
comparable to the local space density and thus that the epoch of formation of
bright galaxies may lie at yet higher redshift.

</DOC>
<DOC>
<DOCNO> 117481 </DOCNO>
The Synchrotron Spectrum of Fast Cooling Electrons Revisited


  We discuss the spectrum arising from synchrotron emission by fast cooling
(FC) electrons, when fresh electrons are continually accelerated by a strong
blast wave, into a power law distribution of energies. The FC spectrum was so
far described by four power law segments divided by three break frequencies
$\nu_{sa} < \nu_{c} < \nu_{m}$. This is valid for a homogeneous electron
distribution. However, hot electrons are located right after the shock, while
most electrons are farther down stream and have cooled. This spatial
distribution changes the optically thick part of the spectrum, introducing a
new break frequency, $\nu_{ac} < \nu_{sa}$, and a new spectral slope, $F_{\nu
}\propto \nu^{11/8}$ for $\nu_{ac} < \nu < \nu_{sa}$. The familiar $F_{\nu
}\propto \nu ^{2}$ holds only for $\nu < \nu_{ac}$. This ordering of the break
frequencies is relevant for typical gamma-ray burst (GRB) afterglows in an ISM
environment. Other possibilities arise for internal shocks or afterglows in
dense circumstellar winds. We discuss possible implications of this spectrum
for GRBs and their afterglows, in the context of the internal-external shock
model. Observations of $F_{\nu} \propto \nu^{11/8}$ would enable us to probe
scales much smaller than the typical size of the system, and constrain the
amount of turbulent mixing behind the shock.

</DOC>
<DOC>
<DOCNO> 85187 </DOCNO>
Fermi co-ordinates and relativistic effects in non-inertial frames


  Fermi co-ordinates are proper co-ordinates of a local observer determined by
his trajectory in space-time. Two observers at different positions belong to
different Fermi frames even if there is no relative motion between them. Use of
Fermi co-ordinates leads to several physical conclusions related to
relativistic effects seen by observers in arbitrary motion. In flat space-time,
the relativistic length seen by an observer depends only on his instantaneous
velocity, not on his acceleration or rotation. In arbitrary space-time, for any
observer the velocity of light is isotropic and equal to $c$, provided that it
is measured by propagating a light beam in a small neighbourhood of the
observer. The value of a covariant field measured at the position of the
observer depends only on his instantaneous position and velocity, not on his
acceleration. The notion of radiation is observer independent. A "freely"
falling charge in curved space-time does not move along a geodesic and
therefore radiates.

</DOC>
<DOC>
<DOCNO> 122991 </DOCNO>
Chemical yields from low- and intermediate-mass stars: model predictions


  In this work we analyse the role of low- and intermediate-mass stars in
contributing to the chemical enrichment of the interstellar medium. First we
present new sets of stellar yields basing on the results of updated
evolutionary calculations, which extend from the ZAMS up to the end of the AGB
phase (Girardi et al. 2000; Marigo et al. 1999a). These new yields, that
present a significant dependence on metallicity, are then compared to those of
other available sets (Renzini & Voli 1981; van de Hoek & Groenewegen 1997). The
resulting differences are explained in terms of different model assumptions --
i.e. treatment of convective boundaries, mass loss, dredge-up, hot-bottom
burning --, and further discussed on the basis of important empirical
constraints which should be reproduced by theory -- i.e. the initial-final mass
relation, white dwarf mass distribution, carbon star luminosity function, and
chemical abundances of planetary nebulae. We show that present models are able
to reproduce such constraints in a satisfactory way.

</DOC>
<DOC>
<DOCNO> 83326 </DOCNO>
Relevance as Deduction: A Logical View of Information Retrieval


  The problem of Information Retrieval is, given a set of documents D and a
query q, providing an algorithm for retrieving all documents in D relevant to
q. However, retrieval should depend and be updated whenever the user is able to
provide as an input a preferred set of relevant documents; this process is
known as em relevance feedback. Recent work in IR has been paying great
attention to models which employ a logical approach; the advantage being that
one can have a simple computable characterization of retrieval on the basis of
a pure logical analysis of retrieval. Most of the logical models make use of
probabilities or similar belief functions in order to introduce the inductive
component whereby uncertainty is treated. Their general paradigm is the
following: em find the nature of conditional $d\imp q$ and then define a
probability on the top of it. We just reverse this point of view; first use the
numerical information, frequencies or probabilities, then define your own
logical consequence. More generally, we claim that retrieval is a form of
deduction. We introduce a simple but powerful logical framework of relevance
feedback, derived from the well founded area of nonmonotonic logic. This
description can help us evaluate, describe and compare from a theoretical point
of view previous approaches based on conditionals or probabilities.

</DOC>
<DOC>
<DOCNO> 169691 </DOCNO>
Symplectic areas, quantization, and dynamics in electromagnetic fields


  A gauge invariant quantization in a closed integral form is developed over a
linear phase space endowed with an inhomogeneous Faraday electromagnetic
tensor. An analog of the Groenewold product formula (corresponding to Weyl
ordering) is obtained via a membrane magnetic area, and extended to the product
of N symbols. The problem of ordering in quantization is related to different
configurations of membranes: a choice of configuration determines a phase
factor that fixes the ordering and controls a symplectic groupoid structure on
the secondary phase space. A gauge invariant solution of the quantum evolution
problem for a charged particle in an electromagnetic field is represented in an
exact continual form and in the semiclassical approximation via the area of
dynamical membranes.

</DOC>
<DOC>
<DOCNO> 10814 </DOCNO>
Enhanced quantized current driven by surface acoustic waves


  We present the experimental realization of different approaches to increase
the amount of quantized current which is driven by surface acoustic waves
through split gate structures in a two dimensional electron gas. Samples with
driving frequencies of up to 4.7 GHz have been fabricated without a
deterioration of the precision of the current steps, and a parallelization of
two channels with correspondingly doubled current values have been achieved. We
discuss theoretical and technological limitations of these approaches for
metrological applications as well as for quantum logics.

</DOC>
<DOC>
<DOCNO> 120881 </DOCNO>
Physical parameters of erupting Luminous Blue Variables: NGC 2363-V1


  A quantitative study of the Luminous Blue Variable NGC 2363-V1 in the
Magellanic galaxy NGC 2366 (D = 3.44 Mpc) is presented, based on ultraviolet
and optical HST/STIS spectroscopy. Contemporary WFPC2 and WHT imaging reveals a
modest V-band brightness increase of ~ 0.2 mag per year between 1996 January
and 1997 November, reaching V=17.4 mag, corresponding to Mv=-10.4 mag.
Subsequently, V1 underwent a similar decrease in V-band brightness, together
with a UV brightening of 0.35 mag from 1997 November to 1999 November.
  The optical spectrum of V1 is dominated by H emission lines, with Fe II, He I
and Na I also detected. In the ultraviolet, a forest of Fe absorption features
and numerous absorption lines typical of mid-B supergiants are observed. From a
spectral analysis with the non-LTE, line-blanketed code of Hillier & Miller
(1998), we derive stellar parameters of T*=11kK, R*=420Ro, log(L/Lo)=6.35
during 1997 November, and T*=13kK, R*=315Ro, log(L/Lo)=6.4 for 1999 July. The
wind properties of V1 are also exceptional, with Mdot ~ 4.4 x 10e-4 Mo/yr and
$v_{\infty} ~ $300 km/s, allowing for a clumped wind (filling factor = 0.3),
and assuming H/He ~ 4 by number.
  The presence of Fe lines in the UV and optical spectrum of V1 permits an
estimate of the heavy elemental abundance of NGC 2363 from our spectral
synthesis. Although some deficiencies remain, allowance for charge exchange
reactions in our calculations supports a SMC-like metallicity, that has
previously been determined for NGC 2363 from nebular oxygen diagnostics.
  Considering a variety of possible progenitor stars, V1 has definitely
undergone a giant eruption, with a substantial increase in stellar luminosity,
radius, and almost certainly mass-loss rate.

</DOC>
<DOC>
<DOCNO> 68053 </DOCNO>
TeV Emission by Ultra-High Energy Cosmic Rays in Nearby, Dormant AGNs


  The curvature radiation produced by particles accelerating near the event
horizon of a spinning supermassive black hole, threaded by externally supported
magnetic field lines is considered. It is shown that light nuclei suffer
catastrophic curvature losses that limit the maximum energy they can attain to
values well below that imposed by the maximum potential difference induced by
the black hole dynamo, unless the curvature radius of magnetic field lines
largely exceeds the gravitational radius. It is further shown that the dominant
fraction of the rotational energy extracted from the black hole is radiated in
the TeV band. Given the observed flux of ultra-high energy cosmic rays, and the
estimated number of nearby supermassive black holes, it is expected that if
dormant AGNs are the sources of UHECRs, as proposed recently by Boldt & Ghosh,
then they should also be detectable at TeV energies by present TeV experiments.

</DOC>
<DOC>
<DOCNO> 10401 </DOCNO>
Step-wise Behavior of Vortex-Lattice Melting Transition in Tilted


  The vortex lattice melting transition in single crystals Bi2Sr2CaCu2O8+d was
studied by the in-plane resistivity measurements in magnetic fields tilted away
from the c-axis to the ab-plane. In order to avoid the surface barrier effect
which hinders the melting transition in the conventional transport
measurements, we used the Corbino geometry of electric contacts. For the first
time, the complete Hc-Hab phase diagram of the melting-transition in
Bi2Sr2CaCu2O8+d is obtained. The c-axis melting field component Hc-melt
exhibits the novel, step-wise dependence on the in-plane magnetic fields Hab
which is discussed on the base of the crossing vortex lattice structure. The
sharp change of resistance behavior observed near the ab-plane suggests
transformation from first-order to second-order phase transition.

</DOC>
<DOC>
<DOCNO> 10305 </DOCNO>
Four-wave mixing in degenerate atomic gases


  We study the process of four-wave mixing (4WM) in ultracold degenerate atomic
gases. In particular we address the problem of 4WM in boson-fermion mixtures.
We develop an approximate description of such processes using asymptotic
analysis of high order perturbation theory taking into account quantum
statistics. We perform also numerical simulations of 4WM in boson-fermion
mixtures and obtain an analytic and numerical estimate of the efficiency of the
process.

</DOC>
<DOC>
<DOCNO> 151067 </DOCNO>
Covariant Schwinger terms


  There exist two versions of the covariant Schwinger term in the literature.
They only differ by a sign. However, we shall show that this is an essential
difference. We shall carefully (taking all signs into account) review the
existing quantum field theoretical computations for the covariant Schwinger
term in order to determine the correct expression.

</DOC>
<DOC>
<DOCNO> 71540 </DOCNO>
Supersymmetric Standard Models on D-Branes


  Type IIB superstring models with the standard model gauge group on D3-branes
and with massless matter associated with open strings joining D3-branes to
D3-branes or D3-branes to ${\rm D}7_3$-branes are studied. Models with gauge
coupling constant unification at an intermediate scale between about $10^{10}$
and $10^{12}$GeV and consistency with the observed value of $\sin^2 \theta_W
(M_Z)$ are obtained. Extra vector-like states and extra pairs of Higgs doublets
play a crucial role.

</DOC>
<DOC>
<DOCNO> 178934 </DOCNO>
Nuclear matter properties in the relativistic mean field model with


  The possibility of extending the linear sigma-omega model by introducing a
sigma-omega coupling phenomenologically is explored. It is shown that, in
contrast to the usual Walecka model, not only the effective nucleon mass M* but
also the effective sigma meson mass m*_sigma and the effective omega meson mass
m*_omega are nucleon density dependent. When the model parameters are fitted to
the nuclear saturation point (the nuclear radius constant r_0=1.14fm and volume
energy a_1=16.0MeV) as well as to the effective nucleon mass M*=0.85M, the
model yields m*_sigma=1.09m_sigma and m*_omega=0.90m_omega at the saturation
point, and the nuclear incompressibility K_0=501MeV. The lowest value of K_0
given by this model by adjusting the model parameters is around 227MeV.

</DOC>
<DOC>
<DOCNO> 99944 </DOCNO>
Universal Similarity Factorization Equalities over Real Clifford


  A variety of universal similarity factorization equalities over real Clifford
algebras ${\cal R}_{p,q}$ are established. On the basis of these equalities,
real, complex and quaternion matrix representations of elements in ${\cal
R}_{p,q}$ can be explicitly determined.

</DOC>
<DOC>
<DOCNO> 117504 </DOCNO>
Evidence for a substellar secondary in the magnetic cataclysmic binary


  Low-state spectrophotometry of the short-period polar EF Eridani (Porb=81
min) found the system at V=18.0 with no trace of the companion (Wheatley and
Ramsay 1998). We show that the lack of such spectral features implies that the
companion to the white dwarf in EF Eri has a spectral type later than M9 and is
either a transition object at the brink of hydrogen burning or a brown dwarf.
The optical low state spectrum indicates a temperature of the white dwarf of
Teff=9500+-500K. This is one of the coldest white dwarfs in cataclysmic
variables, implying a cooling age t_cool>=10e9 yrs or accretional heating at a
rate as given by gravitational radiation. The large age of the system excludes
a warm brown dwarf as companion. EF Eri has either just passed through the
period minimum of cataclysmic variable stars or has started mass transfer from
an old brown dwarf secondary.

</DOC>
<DOC>
<DOCNO> 7730 </DOCNO>
Magnetic relaxation in hard type-II superconductors


  Magnetic relaxation in a type-II superconductor is simulated for a range of
temperatures (T) in a simple model of 2D Josephson junction array (JJA) with
finite screening. The high-T phase, that is characterised by a single time
scale \tau_{\alpha}, crosses over to an intermediate phase at a lower
temperature T_{cr} wherein a second time scale \tau_{\beta}<<\tau_{\alpha}
emerges. The relaxation in the time window set by \tau_{\beta} follows power
law which is attributed to self-organization of the magnetic flux during
relaxation. Consequently, for T<T_{cr}, a transition from super-critical
(current density J>J_{c}) to sub-critical (J<J_{c}) state separated by an
intermediate state with frozen dynamics is observed. Both \tau_{\alpha} and
\tau_{\beta} diverges at T_{sc}<T_{cr}, marking the transition into a state
with true persistent current.

</DOC>
<DOC>
<DOCNO> 116612 </DOCNO>
Trajectories of light


  The trajectories of light are demostrated with experiments made with a
microwave oscilator coupled to a horn antenna and a movable metalic plate along
the radar beam. Two polarizations were made: Linear polarization that produced
double cycloids paths and circular polarization that produced helical paths.
Both trajectories filled the empty space around the trajectories. The new
photon model which is formed by two particles instead of the traditional one,
equations and physical behavior is totally filled.

</DOC>
<DOC>
<DOCNO> 101775 </DOCNO>
Large deviations for a zero mean asymmetric zero range process in random


  We consider an asymmetric zero range process in infinite volume with zero
mean and random jump rates starting from equilibrium. We investigate the large
deviations from the hydrodynamical limit of the empirical distribution of
particles and prove an upper and a lower bound for the large deviation
principle. Our main argument is based on a super-exponential estimate in
infinite volume. For this we extend to our case a method developed by Kipnis &
al. (1989) and Benois & al. (1995).

</DOC>
<DOC>
<DOCNO> 71881 </DOCNO>
Non standard analysis of the solar neutrino anomaly (updated including


  Continuing previous work, a model independent analysis of the solar neutrino
anomaly is performed in terms of neutrino oscillations, allowing a comparison
with the predictions of the Standard Solar Model. SMA and LMA solutions emerge
also in this case, although somewhat different from the standard ones. The
significance of the NC/CC double ratio measurable in SNO is illustrated in this
context.

</DOC>
<DOC>
<DOCNO> 39712 </DOCNO>
The Diffractive Quantum Limits of Particle Colliders


  Quantum Mechanics places limits on achievable transverse beam spot sizes of
particle accelerators. We estimate this limit for a linear collider to be
\Delta x > \hbar c f/E\delta_0 where f is the final focal length, E the beam
energy, and \delta_0 the intrinsic transverse Gaussian width of the electron
wave-function. \delta_0 is determined in the phase space damping rings, and we
find \delta_0 \approx \sqrt{\hbar c /eB} where B is the typical wiggler
magnetic field strength in this system. For the NLC \delta_0 = 25 nm, and
\Delta x = 0.06 nm, about two orders of magnitude smaller than the design goal.
We can recover a crude estimate of the classical result when we include
radiative relaxation effects. We also consider a synchrotron and obtain \Delta
x > \sqrt{\hbar c f/E} = O(1.0) nm. We discuss formulation of quantum beam
optics relevant to these issues.

</DOC>
<DOC>
<DOCNO> 178556 </DOCNO>
Practical approximation scheme for the pion dynamics in the


  We discuss a working approximation scheme to a recently developed formulation
of the coupled piNNN-NNN problem. The approximation scheme is based on the
physical assumption that, at low energies, the 2N-subsystem dynamics in the
elastic channel is conveniently described by the usual 2N-potential approach,
while the explicit pion dynamics describes small, correction-type effects.
Using the standard separable-expansion method, we obtain a dynamical equation
of the Alt-Grassberger-Sandhas (AGS) type. This is an important result, because
the computational techniques used for solving the normal AGS equation can also
be used to describe the pion dynamics in the 3N system once the matrix
dimension is increased by one component. We have also shown that this
approximation scheme treats the conventional 3N problem once the pion degrees
of freedom are projected out. Then the 3N system is described with an extended
AGS-type equation where the spin-off of the pion dynamics (beyond the 2N
potential) is taken into account in additional contributions to the driving
term. These new terms are shown to reproduce the diagrams leading to modern
3N-force models. We also recover two sets of irreducible diagrams that are
commonly neglected in 3N-force discussions, and conclude that these sets should
be further investigated, because a claimed cancellation is questionable.

</DOC>
<DOC>
<DOCNO> 123325 </DOCNO>
Optical and X-ray clusters as tracers of the supercluster-void network.


  We study the distribution of X-ray selected clusters of galaxies with respect
to superclusters determined by Abell clusters of galaxies and show that the
distribution of X-ray clusters follows the supercluster-void network determined
by Abell clusters. We find that in this network X-ray clusters are more
strongly clustered than other clusters. Poor, non-Abell X-ray clusters follow
the supercluster-void network as well: these clusters are embedded in
superclusters determined by rich clusters and populate filaments between them.
We present a new catalog of superclusters of Abell clusters out to a redshift
of z_{lim}=0.13, a catalog of X-ray clusters located in superclusters
determined by Abell clusters, and a list of additional superclusters of X-ray
clusters.

</DOC>
<DOC>
<DOCNO> 121706 </DOCNO>
A New Model for the Evolution of Light Elements in an Inhomogeneous


  We present predictions of the evolution of the light elements, Li, Be, and B,
in the early epochs of the Galactic halo, using a model of supernova-induced
chemical evolution based on contributions from supernovae (SNe) and cosmic rays
(CRs). The most important prediction from our model is that the abundances of
light elements in extremely metal-poor stars might be used as age indicators in
the very early stages of an evolving halo population, at times when metallicity
in most stars are dominated by local metal enrichment due to nearby SN events,
and is poorly correlated with age. Our results show that the best ``cosmic
clock'' is the $^6$Li abundance. We have derived relationships among various
cosmic-ray parameters. Although our model is successful for certain sets of
cosmic-ray parameters, larger energy should be absorbed by energetic particles
from each SN than required to the current situation of Galactic disk. We
discuss an alternative hypothesis of AGN activity in the early Galaxy as
another possible accelerator of CRs.

</DOC>
<DOC>
<DOCNO> 152348 </DOCNO>
Rolling among G_2 vacua


  We consider topology-changing transitions between 7-manifolds of holonomy G_2
constructed as a quotient of CY x S^1 by an antiholomorphic involution. We
classify involutions for Complete Intersection CY threefolds, focussing
primarily on cases without fixed points. The ordinary conifold transition
between CY threefolds descends to a transition between G_2 manifolds,
corresponding in the N=1 effective theory incorporating the light black hole
states either to a change of branch in the scalar potential or to a Higgs
mechanism. A simple example of conifold transition with a fixed nodal point is
also discussed. As a spin-off, we obtain examples of G_2 manifolds with the
same value for the sum of Betti numbers b_2+b_3, and hence potential candidates
for mirror manifolds.

</DOC>
<DOC>
<DOCNO> 84160 </DOCNO>
Boson stars in massive dilatonic gravity


  We study equilibrium configurations of boson stars in the framework of a
class scalar-tensor theories of gravity with massive gravitational scalar
(dilaton). In particular we investigate the influence of the mass of the
dilaton on the boson star structure. We find that the masses of the boson stars
in presence of dilaton are close to those in general relativity and they are
sensitive to the ratio of the boson mass to the dilaton mass within a typical
few percent. It turns out also that the boson star structure is mainly
sensitive to the mass term of the dilaton potential rather to the exact form of
the potential.

</DOC>
<DOC>
<DOCNO> 100561 </DOCNO>
A Power Function with A Fixed Finite Gap Everywhere


  We give an application of our extender based Radin forcing to cardinal
arithmetic. Using a preparation forcing and interleaving of Cohen and Levy
forcings in the normal Radin sequence we get a model with a power function
having a fixed finite gap on all cardinals.

</DOC>
<DOC>
<DOCNO> 99314 </DOCNO>
From random sets to continuous tensor products: answers to three


  The set of zeros of a Brownian motion gives rise to a product system in the
sense of William Arveson (that is, a continuous tensor product system of
Hilbert spaces). Replacing the Brownian motion with a Bessel process we get a
continuum of non-isomorphic product systems.

</DOC>
<DOC>
<DOCNO> 151250 </DOCNO>
A Consistent Noncommutative Field Theory: the Wess-Zumino Model


  We show that the noncommutative Wess-Zumino model is renormalizable to all
orders of perturbation theory. The noncommutative scalar potential by itself is
non-renormalizable but the Yukawa terms demanded by supersymmetry improve the
situation turning the theory into a renormalizable one. As in the commutative
case, there are neither quadratic nor linear divergences. Hence, the IR/UV
mixing does not give rise to quadratic infrared poles.

</DOC>
<DOC>
<DOCNO> 8102 </DOCNO>
Condensed Matter Physics - Biology Resonance


  The field of condensed matter physics had its genesis this century and it has
had a remarkable evolution. A closer look at its growth reveals a hidden aim in
the collective consciousness of the field - a part of the development this
century is a kind of warm up exercise to understand the nature of living
condensed matter, namely the field of biology, by a growing new breed of
scientists in the coming century. Through some examples the vitality of this
interaction will be pointed out.

</DOC>
<DOC>
<DOCNO> 39923 </DOCNO>
Measurements of Z0 Electroweak Couplings at SLD


  We present a summary of the results of several electroweak measurements
performed by the SLD experiment at the Stanford Linear Collider (SLC). Most of
these results are preliminary and are based, unless otherwise indicated, on the
full 1993-8 data set of approximately 550,000 hadronic decays of Z0 bosons
produced with an average electron beam polarization of 73%.

</DOC>
<DOC>
<DOCNO> 7821 </DOCNO>
Holon Pairing Instability based on the Bethe-Salpeter Equation obtained


  We investigate a possibility of holon pairing for bose condensation based on
the
 Bethe-Salpeter equation obtained from the use of the t-J Hamiltonians of both
t he U(1) and SU(2) slave-boson symmetries. It is shown that the vertex
function contributed from ladder diagram series involving holon-holon
scattering channel in the Bethe-Salpeter equation leads to a singular behavior
at a critical temperature at each hole doping concentration, showing the
instability of the normal state against holon pairing. We find that the holon
pairing instability occurs only in a limited range of hole doping, by showing
an "arch" shaped bose condensation line in agreement with observation for high
$T_c$ cuprates. It is revealed that this is in agreement with a functional
integral approach of the slave-boson theories.

</DOC>
<DOC>
<DOCNO> 11808 </DOCNO>
Mapping atomistic to coarse-grained polymer models using automatic


  We develop coarse-grained force fields for poly (vinyl alcohol) and poly
(acrylic acid) oligomers. In both cases, one monomer is mapped onto a
coarse-grained bead. The new force fields are designed to match structural
properties such as radial distribution functions of various kinds derived by
atomistic simulations of these polymers. The mapping is therefore constructed
in a way to take into account as much atomistic information as possible. On the
technical side, our approach consists of a simplex algorithm which is used to
optimize automatically non-bonded parameters as well as bonded parameters.
Besides their similar conformation (only the functional side group differs),
poly (acrylic acid) was chosen to be in aqueous solution in contrast to a poly
(vinyl alcohol) melt. For poly (vinyl alcohol) a non-optimized bond angle
potential turns out to be sufficient in connection with a special, optimized
non-bonded potential. No torsional potential has to be applied here. For poly
(acrylic acid), we show that each peak of the radial distribution function is
usually dominated by some specific model parameter(s). Optimization of the bond
angle parameters is essential. The coarse-grained forcefield reproduces the
radius of gyration of the atomistic model. As a first application, we use the
force field to simulate longer chains and compare the hydrodynamic radius with
experimental data.

</DOC>
<DOC>
<DOCNO> 70878 </DOCNO>
Status of theoretical B -> X_s gamma and B -> X_s l^+ l^- analyses


  Status of the theoretical B -> X_s gamma and B -> X_s l^+ l^- analyses is
reviewed. Recently completed perturbative calculations are mentioned. The level
at which non-perturbative effects are controlled is discussed.

</DOC>
<DOC>
<DOCNO> 178495 </DOCNO>
Generating new solutions for relativistic transverse flow at the softest


  Using the method of prolongation we generate new solutions from a simple
particular solution for relativistic transverse flow with cylindrical symmetry
in 1+3 dimensions. This is an extension of the longitudinal Bjorken flow ansatz
and can be applied among others during first order phase transition in an
expanding system. The prolongated solution allows for tracing back the flow
profile from a transverse flow conjectured at the end of phase transition at
CERN SPS heavy ion collisons.

</DOC>
<DOC>
<DOCNO> 85592 </DOCNO>
Gravitational radiation, energy and reaction on quasi-spherical black


  Gravitational radiation is locally defined where the wavefronts are roughly
spherical. A local energy tensor is defined for the gravitational radiation.
Including this energy tensor as a source in the truncated Einstein equations
describes gravitational radiation reaction, such as back-reaction on a roughly
spherical black hole. The energy-momentum in a canonical frame is covariantly
conserved. The strain to be measured by a distant detector is simply defined.

</DOC>
<DOC>
<DOCNO> 39671 </DOCNO>
Parametrization of polarized parton distribution functions


  Polarized parton distribution functions are determined by using asymmetry A_1
data from longitudinally polarized deep inelastic scattering experiments. From
our \chi^2 analysis, polarized u-valence, d-valence, antiquark, and gluon
distributions are obtained. We propose one set of leading-order distributions
and two sets of next-to-leading-order ones as the longitudinally-polarized
parton distribution functions.

</DOC>
<DOC>
<DOCNO> 119934 </DOCNO>
The inverse cascade and nonlinear alpha-effect in simulations of


  A numerical model of isotropic homogeneous turbulence with helical forcing is
investigated. The resulting flow, which is essentially the prototype of the
alpha^2 dynamo of mean-field dynamo theory, produces strong dynamo action with
an additional large scale field on the scale of the box (at wavenumber k=1;
forcing is at k=5). This large scale field is nearly force-free and exceeds the
equipartition value. As the magnetic Reynolds number R_m increases, the
saturation field strength and the growth rate of the dynamo increase. However,
the time it takes to built up the large scale field from equipartition to its
final super-equipartition value increases with magnetic Reynolds number. The
large scale field generation can be identified as being due to nonlocal
interactions originating from the forcing scale, which is characteristic of the
alpha-effect. Both alpha and turbulent magnetic diffusivity eta_t are
determined simultaneously using numerical experiments where the mean-field is
modified artificially. Both quantities are quenched in a R_m-dependent fashion.
The evolution of the energy of the mean field matches that predicted by an
alpha^2 dynamo model with similar alpha and eta_t quenchings. For this model an
analytic solution is given which matches the results of the simulations. The
simulations are numerically robust in that the shape of the spectrum at large
scales is unchanged when changing the resolution from 30^3 to 120^3 meshpoints,
or when increasing the magnetic Prandtl number (viscosity/magnetic diffusivity)
from 1 to 100. Increasing the forcing wavenumber to 30 (i.e. increasing the
scale separation) makes the inverse cascade effect more pronounced, although it
remains otherwise qualitatively unchanged.

</DOC>
<DOC>
<DOCNO> 102203 </DOCNO>
Ricci flow on Kaehler manifolds


  In this paper, we announce the following results: Let M be a Kaehler-Einstein
manifold with positive scalar curvature. If the initial metric has nonnegative
bisectional curvature and positive at least at one point, then the
K\"ahler-Ricci flow converges exponentially fast to a Kaehler-Einstein metric
with constant bisectional curvature.

</DOC>
<DOC>
<DOCNO> 121853 </DOCNO>
GRB Afterglows from Anisotropic Jets


  Some progenitor models of gamma-ray bursts (GRBs) (e.g., collapsars) may
produce anisotropic jets in which the energy per unit solid angle is a
power-law function of the angle ($\propto\theta^{-k}$). We calculate light
curves and spectra for GRB afterglows when such jets expand either in the
interstellar medium or in the wind medium. In particular, we take into account
two kinds of wind: one ($n\propto r^{-3/2}$) possibly from a typical red
supergiant star and another ($n\propto r^{-2}$) possibly from a Wolf-Rayet
star. We find that in each type of medium, one break appears in the late-time
afterglow light curve for small $k$ but becomes weaker and smoother as $k$
increases. When $k\ge 2$, the break seems to disappear but the afterglow decays
rapidly. Thus, one expects that the emission from expanding, highly anisotropic
jets provides a plausible explanation for some rapidly fading afteglows whose
light curves have no break. We also present good fits to the optical afterglow
light curve of GRB 991208. Finally, we argue that this burst might arise from a
highly anisotropic jet expanding in the wind ($n\propto r^{-3/2}$) from a red
supergiant to interpret the observed radio-to-optical-band afterglow data
(spectrum and light curve).

</DOC>
<DOC>
<DOCNO> 122503 </DOCNO>
PMN J0525-3343: soft X-ray spectral flattening in a blazar at z=4.4


  We report optical, radio and X-ray observations of a new distant blazar, PMN
J0525-3343, at a redshift of 4.4. The X-ray spectrum measured from ASCA and
BeppoSAX flattens below a few keV, in a manner similar to the spectra of two
other z>4 blazars, GB 1428+4217 (z=4.72) reported by Boller et al and RXJ
1028.6-0844 (z=4.28) by Yuan et al. The spectrum is well fitted by a power-law
continuum which is either absorbed or breaks at a few keV. An intrinsic column
density corresponding to 2 x 10^23 H-atoms cm-2 at solar abundance is required
by the absorption model. This is however a million times greater than the
neutral hydrogen, or dust, column density implied by the optical spectrum,
which covers the rest-frame UV emission of the blazar nucleus. We discuss the
problems raised and suggest that, unless there is intrinsic flattening in the
spectral distribution of the particles/seed photons producing X-rays via
inverse Compton scattering, the most plausible solution is a warm absorber
close to the active nucleus.

</DOC>
<DOC>
<DOCNO> 150563 </DOCNO>
Class of self-dual models in three dimensions


  In the present paper we introduce a hierarquical class of self-dual models in
three dimensions, inspired in the original self-dual theory of
Towsend-Pilch-Nieuwenhuizen. The basic strategy is to explore the powerful
property of the duality transformations in order to generate a new field. The
generalized propagator can be written in terms of the primitive one (first
order), and also the respective order and disorder correlation functions. Some
conclusions about the ``charge screening'' and magnetic flux were established.

</DOC>
<DOC>
<DOCNO> 122866 </DOCNO>
Synthesis of Small and Large scale Dynamos


  Using a closure model for the evolution of magnetic correlations, we uncover
an interesting plausible saturated state of the small-scale fluctuation dynamo
(SSD) and a novel anology between quantum mechanical tunneling and the
generation of large-scale fields. Large scale fields develop via the
$\alpha$-effect, but as magnetic helicity can only change on a resistive
timescale, the time it takes to organize the field into large scales increases
with magnetic Reynolds number. This is very similar to the results which obtain
from simulations using full MHD.

</DOC>
<DOC>
<DOCNO> 118322 </DOCNO>
CMB Anisotropies and the Determination of Cosmological Parameters


  I review the basic theory of the cosmic microwave background anisotropies in
adiabatic cold dark matter cosmologies. The latest observational results on the
CMB power spectrum are consistent with the simplest inflationary models and
indicate that the Universe is close to spatially flat with a nearly scale
invariant fluctuation spectrum. We are also beginning to see interesting
constraints on the density of CDM, with a best fit value of omega_c = Omega_c
h^2 of about 0.1. The CMB constraints, when combined with observations of
distant Type Ia supernovae, are converging on a Lambda-dominated Universe with
Omega_m approx 0.3 and Omega_Lambda approx 0.7.

</DOC>
<DOC>
<DOCNO> 84451 </DOCNO>
Lectures on Strings, D-branes and Gauge Theories


  In these lectures we review the basic ideas of perturbative and
non-perturbative string theory. On the non-perturbative side we give an
introduction to D-branes and string duality. The elementary concepts of non-BPS
branes and noncommutative gauge theories are also discussed.

</DOC>
<DOC>
<DOCNO> 151621 </DOCNO>
Bound state equation for 4 or more relativistic particles


  We apply the 3D reduction method we recently proposed for the N-particle
Bethe-Salpeter equation to the 4-particle case. We find that the writing of the
Bethe-Salpeter equation is not a straightforward task when N is larger or equal
to 4, owing to the presence of mutually unconnected interactions, which could
lead to an overcounting of some diagrams in the resulting full propagator. We
overcome this difficulty in the N=4 case by including three counterterms in the
Bethe-Salpeter kernel. The application of our 3D reduction method to the
resulting Bethe-Salpeter equation suggests us a modified 3D reduction method,
which gives directly the 3D potential, without the need of writing the
Bethe-Salpeter kernel explicitly. The modified reduction method is usable for
all N.

</DOC>
<DOC>
<DOCNO> 150977 </DOCNO>
Yang-Mills Integrals for Orthogonal, Symplectic and Exceptional Groups


  We apply numerical and analytic techniques to the study of Yang-Mills
integrals with orthogonal, symplectic and exceptional gauge symmetries. The
main focus is on the supersymmetric integrals, which correspond essentially to
the bulk part of the Witten index for susy quantum mechanical gauge theory. We
evaluate these integrals for D=4 and group rank up to three, using Monte Carlo
methods. Our results are at variance with previous findings. We further compute
the integrals with the deformation technique of Moore, Nekrasov and
Shatashvili, which we adapt to the groups under study. Excellent agreement with
all our numerical calculations is obtained. We also discuss the convergence
properties of the purely bosonic integrals.

</DOC>
<DOC>
<DOCNO> 122812 </DOCNO>
Naked eye star visibility and limiting magnitude mapped from DMSP-OLS


  We extend the method introduced by Cinzano et al. (2000a) to map the
artificial sky brightness in large territories from DMSP satellite data, in
order to map the naked eye star visibility and telescopic limiting magnitudes.
For these purposes we take into account the altitude of each land area from
GTOPO30 world elevation data, the natural sky brightness in the chosen sky
direction, based on Garstang modelling, the eye capability with naked eye or a
telescope, based on the Schaefer (1990) and Garstang (2000b) approach, and the
stellar extinction in the visual photometric band. For near zenith sky
directions we also take into account screening by terrain elevation. Maps of
naked eye star visibility and telescopic limiting magnitudes are useful to
quantify the capability of the population to perceive our Universe, to evaluate
the future evolution, to make cross correlations with statistical parameters
and to recognize areas where astronomical observations or popularisation can
still acceptably be made. We present, as an application, maps of naked eye star
visibility and total sky brightness in V band in Europe at the zenith with a
resolution of approximately 1 km.

</DOC>
<DOC>
<DOCNO> 170558 </DOCNO>
Environment-Induced Decoherence and the Transition From Quantum to


  We study dynamics of quantum open systems, paying special attention to those
aspects of their evolution which are relevant to the transition from quantum to
classical. We begin with a discussion of the conditional dynamics of simple
systems. The resulting models are straightforward but suffice to illustrate
basic physical ideas behind quantum measurements and decoherence. To discuss
decoherence and environment-induced superselection einselection in a more
general setting, we sketch perturbative as well as exact derivations of several
master equations valid for various systems. Using these equations we study
einselection employing the general strategy of the predictability sieve.
Assumptions that are usually made in the discussion of decoherence are
critically reexamined along with the ``standard lore'' to which they lead.
Restoration of quantum-classical correspondence in systems that are classically
chaotic is discussed. The dynamical second law -it is shown- can be traced to
the same phenomena that allow for the restoration of the correspondence
principle in decohering chaotic systems (where it is otherwise lost on a very
short time-scale). Quantum error correction is discussed as an example of an
anti-decoherence strategy. Implications of decoherence and einselection for the
interpretation of quantum theory are briefly pointed out.

</DOC>
<DOC>
<DOCNO> 121849 </DOCNO>
Physical Parameters for the Afterglows of GRB 980703, 990123, 990510,


  We model the radio, optical, and X-ray emission for the afterglows of GRB
980703, 990123, 990510, and 991216, within the framework of relativistic jets,
to determine their physical parameters. The models that yield acceptable fits
to the data have jet energies mostly between 10^{50} to 10^{51} erg and initial
opening angles between 1 deg and 4 deg. The external medium density is
uncertain by at least one order of magnitude in each case, being around
10^{-3}/cm^3 for GRB 980703 and 990123, ~0.1/cm^3 for GRB 990510, and ~3/cm^3
for GRB 991216. If the jets are uniform (i.e. there are no angular gradients of
the energy per solid angle) then the 20 keV -- 1 MeV radiative efficiency
during the GRB phase must have been at least 2-3% for GRB 990510, 20% for GRB
990123, and 30% for GRB 991216.

</DOC>
<DOC>
<DOCNO> 10047 </DOCNO>
Thermodynamics of Multi-Component Fermi Vapors


  We study the thermodynamical properties of Fermi vapors confined in a
harmonic external potential. In the case of the ideal Fermi gas, we compare
exact density profiles with their semiclassical approximation in the conditions
of recent experiments. Then, we consider the phase-separation of a
multi-component Fermi vapor. In particular, we analyze the phase-separation as
a function of temperature, number of particles and scattering length. Finally,
we discuss the effect of rotation on the stability and thermodynamics of the
trapped vapors.

</DOC>
<DOC>
<DOCNO> 11588 </DOCNO>
The stress field in granular systems: Loop forces and potential


  The transmission of stress through a marginally stable granular pile in two
dimensions is exactly formulated in terms of a vector field of loop forces, and
thence in terms of a single scalar potential.
  The loop force formulation leads to a local constitutive equation coupling
the stress tensor to {\it fluctuations} in the local geometry. For a disordered
pile of rough grains (even with simple orientational order) this means the
stress tensor components are coupled in a frustrated manner, analogous to a
spin glass.
  If the local geometry of the pile of rough grains has long range staggered
order, frustration is avoided and a simple linear theory follows. Known exact
lattice solutions for rough grains fall into this class.
  We show that a pile of smooth grains (lacking friction) can always be mapped
into a pile of unfrustrated rough grains. Thus it appears that the problems of
rough and smooth grains may be fundamentally distinct.

</DOC>
<DOC>
<DOCNO> 123029 </DOCNO>
The microwave background temperature at the redshift of 2.33771


  The Cosmic Microwave Background radiation is a fundamental prediction of Hot
Big Bang cosmology. The temperature of its black-body spectrum has been
measured at the present time, $T_{\rm CMBR,0}$ = 2.726$\pm$ 0.010 K, and is
predicted to have been higher in the past. At earlier time, the temperature can
be measured, in principle, using the excitation of atomic fine structure levels
by the radiation field. All previous measurements however give only upper
limits as they assume that no other significant source of excitation is
present. Here we report the detection of absorption from the first {\sl and}
second fine-structure levels of neutral carbon atoms in an isolated remote
cloud at a redshift of 2.33771. In addition, the unusual detection of molecular
hydrogen in several rotational levels and the presence of ionized carbon in its
excited fine structure level make the absorption system unique to constrain,
directly from observation, the different excitation processes at play. It is
shown for the first time that the cosmic radiation was warmer in the past. We
find 6.0 < T_{\rm CMBR} < 14 K at z = 2.33771 when 9.1 K is expected in the Hot
Big Bang cosmology.

</DOC>
<DOC>
<DOCNO> 9696 </DOCNO>
A model of a pumped continuous atom laser


  We present a model of a cw atom laser based on a system of coupled GP
equations. The model incorporates continuous Raman outcoupling, pumping and
three-body recombination. The outcoupled field has minimal atomic density
fluctuations and is locally monochromatic.

</DOC>
<DOC>
<DOCNO> 121110 </DOCNO>
TiO and H$_2$O absorption lines in cool stellar atmospheres


  We compare the structures of model atmospheres and synthetic spectra
calculated using different line lists for TiO and water vapor. We discuss the
effects of different line list combinations on the model strutures and spectra
for both dwarf and giant stars. It is shown that recent improvements result in
significantly improved spectra, in particular in the optical where TiO bands
are important. The water vapor dominated near-IR region remains problematic as
the current water line lists do not yet completely reproduce the shapes of the
observed spectra. We find that the AMES TiO list provides more opacity in most
bands and that the new, smaller oscillator strengths lead to systematically
cooler temperatures for early type M dwarfs than previous models. These effects
combine and will help to siginificantly improve the fits of models to
observations in the optical as well as result in improved synthetic photometry
of M stars. We show that the Davis 1986 \fel-values for the $\delta$ and $\phi$
bands of TiO best reproduce the observed (V-I) color indices.

</DOC>
<DOC>
<DOCNO> 118263 </DOCNO>
Inflationary Models and Connections to Particle Physics


  The basic workings of inflationary models are summarized, along with the
arguments that strongly suggest that our universe is the product of inflation.
The mechanisms that lead to eternal inflation in both new and chaotic models
are described. Although the infinity of pocket universes produced by eternal
inflation are unobservable, it is argued that eternal inflation has real
consequences in terms of the way that predictions are extracted from
theoretical models. The ambiguities in defining probabilities in eternally
inflating spacetimes are reviewed, with emphasis on the youngness paradox that
results from a synchronous gauge regularization technique. To clarify (but not
resolve) this ambiguity, a toy model of an eternally inflating universe is
introduced. Vilenkin's proposal for avoiding these problems is also discussed,
as is the question of whether it is meaningful to discuss probabilities for
unrepeatable measurements.

</DOC>
<DOC>
<DOCNO> 102264 </DOCNO>
Incompressible surfaces in link complements


  We generalize a theorem of Finkelstein and Moriah and show that if a link $L$
has a $2n$-plat projection satisfying certain conditions, then its complement
contains some closed essential surfaces. In most cases these surfaces remain
essential after any totally nontrivial surgery on $L$.

</DOC>
<DOC>
<DOCNO> 83426 </DOCNO>
Enriching very large ontologies using the WWW


  This paper explores the possibility to exploit text on the world wide web in
order to enrich the concepts in existing ontologies. First, a method to
retrieve documents from the WWW related to a concept is described. These
document collections are used 1) to construct topic signatures (lists of
topically related words) for each concept in WordNet, and 2) to build
hierarchical clusters of the concepts (the word senses) that lexicalize a given
word. The overall goal is to overcome two shortcomings of WordNet: the lack of
topical links among concepts, and the proliferation of senses. Topic signatures
are validated on a word sense disambiguation task with good results, which are
improved when the hierarchical clusters are used.

</DOC>
<DOC>
<DOCNO> 7823 </DOCNO>
Reducing quasi-ergodicity in a double well potential by Tsallis Monte


  A new Monte Carlo scheme based on the system of Tsallis's generalized
statistical mechanics is applied to a simple double well potential to calculate
the canonical thermal average of potential energy. Although we observed serious
quasi-ergodicity when using the standard Metropolis Monte Carlo algorithm, this
problem is largely reduced by the use of the new Monte Carlo algorithm.
Therefore the ergodicity is guaranteed even for short Monte Carlo steps if we
use this new canonical Monte Carlo scheme.

</DOC>
<DOC>
<DOCNO> 8220 </DOCNO>
Magnetic Field Effect on the Supercurrent of an SNS junction


  In this paper we study the effect of a Zeeman field on the supercurrent of a
mesoscopic SNS junction. It is shown that the supercurrent suppression is due
to a redistribution of current-carrying states in energy space. A dramatic
consequence is that (part of the) the suppressed supercurrent can be recovered
with a suitable non-equilibrium distribution of quasiparticles.

</DOC>
<DOC>
<DOCNO> 70308 </DOCNO>
Strong Bootstrap Conditions


  We reformulate the so-called ``strong bootstrap'' conditions for the gluon
Reggeization in the next-to-leading approximation (NLA), firstly suggested by
Braun and Vacca, using a different approach, which is not based on properties
of the eigenstates of the NLA octet BFKL kernel. We write the second strong
bootstrap condition for the NLA octet impact factors in a form which makes
clear their dependence on the process. According to this condition, the NLA
octet impact factors must be given by the product of the corresponding Reggeon
interaction vertices with a universal coefficient function. This function can
be used also in the formulation of the first strong bootstrap condition for the
NLA BFKL kernel in the octet state.

</DOC>
<DOC>
<DOCNO> 170274 </DOCNO>
The Universality of the Quantum Fourier Transform in Forming the Basis


  The quantum Fourier transform (QFT) is a powerful tool in quantum computing.
The main ingredients of QFT are formed by the Walsh-Hadamard transform H and
phase shifts P(.), both of which are 2x2 unitary matrices as operators on the
two-dimensional 1-qubit space. In this paper, we show that H and P(.) suffice
to generate the unitary group U(2) and, consequently, through controlled-U
operations and their concatenations, the entire unitary group U(2^n) on
n-qubits can be generated. Since any quantum computing algorithm in an n-qubit
quantum computer is based on operations by matrices in U(2^n), in this sense we
have the universality of the QFT.

</DOC>
<DOC>
<DOCNO> 99685 </DOCNO>
Ideal Perturbation Lemma


  We explain the essence of perturbation problems. The key to understanding is
the structure of chain homotopy equivalence -- the standard one must be
replaced by a finer notion which we call a strong chain homotopy equivalence.
We prove an Ideal Perturbation Lemma and show how both new and classical
results follow from this ideal statement.

</DOC>
<DOC>
<DOCNO> 7879 </DOCNO>
The Onset of Phase Transitions in Condensed Matter and Relativistic QFT


  Kibble and Zurek have provided a unifying causal picture for the appearance
of topological defects like cosmic strings or vortices at the onset of phase
transitions in relativistic QFT and condensed matter systems respectively.
There is no direct experimental evidence in QFT, but in condensed matter the
predictions are largely, but not wholly, supported in superfluid experiments on
liquid helium. We provide an alternative picture for the initial appearance of
strings/vortices that is commensurate with all the experimental evidence from
condensed matter and consider some of its implications for QFT.

</DOC>
<DOC>
<DOCNO> 118258 </DOCNO>
The Asiago-ESO/RASS QSO Survey. I.The Catalog and the Local QSO


  This paper presents the first results of a survey for bright quasars (V <
14.5 and R<15.4) covering the North Hemisphere at galactic latitudes |b|>30.
The photometric database is derived from the GSC and USNO catalogs. Quasars are
identified on the basis of their X-ray emission measured in the ROSAT All Sky
Survey. The surface density of quasars brighter than 15.5 mag turns out to be
$9 \pm 1 \cdot 10^{-3} deg^{-2}$, about 3 times higher than that estimated by
the PG survey. The quasar optical Luminosity Function (LF) at $0.04 < z \le
0.3$ is computed and shown to be consistent with a Luminosity Dependent
Luminosity Evolution of the type derived by La Franca and Cristiani (1997) in
the range $0.3 < z \le 2.2$. The predictions of semi-analytical models of
hierarchical structure formation agree remarkably well with the present
observations.

</DOC>
<DOC>
<DOCNO> 102625 </DOCNO>
Simple singularities of multigerms of curves


  We classify stably simple reducible curve singularities in complex spaces of
any dimension. This extends the same classification of of irreducible curve
singularities obtained by V.I.Arnold. The proof is essentially based on the
method of complete transversals by J.W.Bruce et al.

</DOC>
<DOC>
<DOCNO> 152239 </DOCNO>
Noncommutative Tachyon from Background Independent Open String Field


  We analyze the tachyon field in the bosonic open string theory in a constant
B-field background using the background independent open string field theory.
We show that in the large noncommutativity limit the action of tachyon field is
given exactly by the potential term which has the same form as in the case
without B-field but the product of tachyon field is taken to be the star
product.

</DOC>
<DOC>
<DOCNO> 13187 </DOCNO>
Role of intergranular silver in modulating the aperiodicity in


  Relaxation of the intergranular critical state has been observed at a very
low applied magnetic field (10-50 Oe) over a temperature regime of 20-77 K in
bulk polycrystalline YBa(2)Cu(3)O(7-x) (YBCO) and
Bi(1.75)Pb(0.35)Sr(2)Ca(2)Cu(3)O(10+x) (BPSCCO) samples. In such a disordered
Josephson junction network, the relaxation is slower than the intragranular
relaxation and, hence, it yields higher flux pinning energy U0 than the
corresponding intragranular values. Silver addition seems to have given rise to
much uniformity in the grain boundary characteristics which results in sharp
drop in the flux pinning energy since it depends on the variation of the
junction coupling energy EJ across the network. While U0 ~ 0.5 and 0.55 eV for
the parent BPSCCO and YBCO samples, respectively, in silver added (10-15 wt%)
samples the corresponding values are ~0.15 and 0.27 eV. The distribution
functions m(U) for the flux pinning energy and n(theta) for the grain boundary
mis-alignment angle(theta) have been evaluated from the experimentally observed
patterns of magnetic relaxation and variation of the grain boundary critical
fields with temperature. The distribution functions become narrower in the case
of silver added samples reflecing a reduction in the degree of disorder. The
variation of the effective vortex mass m* with the variation in the degree of
disorder is observed. Considering the width of the superconducting transition
delTc as the measure of the degree of disorder (inhomogeneity), it has been
shown that the transport critical current density Jc follows a relationship Jc
\~ exp(-delTc) while the flux pinning energy U ~ delTc. These relations may help
in devising a suitable strategy for achieving the desired effect : high Jc yet
slower decay rate, i.e., large U.

</DOC>
<DOC>
<DOCNO> 12557 </DOCNO>
MaxEnt Queries and Sequential Sampling


  In this paper we pose the question: After gathering N data points, at what
value of the control parameter should the next measurement be done?
  We propose an on-line algorithm which samples optimally by maximizing the
gain in information on the parameters to be measured. We show analytically that
the information gain is maximum for those potential measurements whose outcome
is most unpredictable, i.e. for which the predictive distribution has maximum
entropy. The resulting algorithm is applied to exponential analysis.

</DOC>
<DOC>
<DOCNO> 122830 </DOCNO>
$\Lambda$-Inflation and CMBR Anisotropy


  We argue that a $\Lambda$-inflation model can ensure large relative
contribution of cosmic gravity waves into the $\Delta T/T$ at COBE scale
preserving at the same time a near scale-invariant spectrum of cosmological
density perturbations favored by observational data ($n_S\simeq 1$). High
efficiency of these models to meet observational tests is discussed.

</DOC>
<DOC>
<DOCNO> 85287 </DOCNO>
The r-mode instability in rotating neutron stars


  In this review we summarize the current understanding of the
gravitational-wave driven instability associated with the so-called r-modes in
rotating neutron stars. We discuss the nature of the r-modes, the detailed
mechanics of the instability and its potential astrophysical significance. In
particular we discuss results regarding the spin-evolution of nascent neutron
stars, the detectability of r-mode gravitational waves and mechanisms limiting
the spin-rate of accreting neutron stars in binary systems.

</DOC>
<DOC>
<DOCNO> 170112 </DOCNO>
Complete Bell state measurement with controlled photon absorption and


  A solid state device to discriminate all the four Bell states is proposed.
The device is composed of controlled absorption crystals, rotators, and
retarders. The controlled absorption, where the state of one photon affects the
absorption of the other photon, is realized by two photon absorption in a cubic
crystal. The controlled absorption crystal detects a particular Bell state and
is transparent for the other Bell states. The rotators and retarders transform
a Bell state to another. This device may solve the problems in the early
quantum teleportation experiments in photon polarization states.

</DOC>
<DOC>
<DOCNO> 69138 </DOCNO>
Prospects of Detecting Baryon and Quark Superfluidity from Cooling


  Baryon and quark superfluidity in the cooling of neutron stars are
investigated. Observations could constrain combinations of the neutron or
Lambda-hyperon pairing gaps and the star's mass. However, in a hybrid star with
a mixed phase of hadrons and quarks, quark gaps larger than a few tenths of an
MeV render quark matter virtually invisible for cooling. If the quark gap is
smaller, quark superfluidity could be important, but its effects will be nearly
impossible to distinguish from those of other baryonic constituents.

</DOC>
<DOC>
<DOCNO> 67873 </DOCNO>
A Pomeron Approach to Hadron-Nucleus and Nucleus-Nucleus "Soft"


  We formulate a generalization of the Glauber formalism for hadron-nucleus and
nucleus-nucleus collisions based on the Pomeron approach to high energy
interactions. Our treatment is based on two physical assumptions (i.e. two
small parameters) : (i) that only sufficiently small distances contribute to
the Pomeron structure; and (ii) the triple Pomeron vertex $G_{3P}/g_{P-N}
  \ll 1$ (where $g_{P-N}$ is the Pomeron-nucleon vertex) is small. A systematic
method is developed for calculating the total, elastic and diffractive
dissociation cross sections as well as the survival probability of large
rapidity gap processes and inclusive observables, both for hadron - nucleus and
nucleus-nucleus collisions. Our approach suggests saturation of the density of
the produced hadrons in nucleus-nucleus collisions, the value of the saturation
density turns out to be large and depends on the number of nucleons in the
lightest nucleus.

</DOC>
<DOC>
<DOCNO> 116723 </DOCNO>
Prediction of long term stability by extrapolation


  This paper studies the possibility of using the survival function to predict
long term stability by extrapolation. The survival function is a function of
the initial coordinates and is the number of turns a particle will survive for
a given set of initial coordinates. To determine the difficulties in
extrapolating the survival function, tracking studies were done to compute the
survival function. The survival function was found to have two properties that
may cause difficulties in extrapolating the survival function. One is the
existence of rapid oscillations, and the second is the existence of plateaus.
It was found that it appears possible to extrapolate the survival function to
estimate long term stability by taking the two difficulties into account. A
model is proposed which pictures the survival function to be a series of
plateaus with rapid oscillations superimposed on the plateaus. The tracking
studies give results for the widths of these plateaus and for the seperation
between adjacent plateaus which can be used to extrapolate and estimate the
location of plateaus that indicate survival for longer times than can be found
by tracking.

</DOC>
<DOC>
<DOCNO> 72152 </DOCNO>
Cosmological Phase Transitions in a Brane World


  In brane world scenarios the Friedmann equation is modified, resulting in an
increased expansion at early times. This has important effects on cosmological
phase transitions which we investigate, elucidating significant differences to
the standard case. First order phase transitions require a higher nucleation
rate to complete; baryogenesis and particle abundances could be suppressed.
Topological defect evolution is also affected, though the current defect
densities are largely unchanged. In particular, the increased expansion does
not solve the usual monopole and domain wall problems.

</DOC>
<DOC>
<DOCNO> 70392 </DOCNO>
Higgs Particles in the Standard Model and Supersymmetric Theories


  This thesis presents a theoretical analysis of the properties of the Higgs
bosons in the Standard Model (SM) and the minimal supersymmetric extension
(MSSM), which can be investigated at the LHC and $e^+e^-$ linear colliders. The
final goal is the reconstruction of the Higgs potential and thus the
verification of the Higgs mechanism. MSSM Higgs boson production processes at
future $\gamma\gamma$ colliders are calculated in several decay channels. Heavy
scalar and pseudoscalar Higgs bosons can be discovered in the $b\bar{b}$ final
state in the investigated mass range 200 to 800 GeV for moderate and large
values of $\tan\beta$. The $\tau^+\tau^-$ channel provides a heavy Higgs boson
discovery potential for large values of $\tan\beta$. Several mechanisms that
can be exploited at $e^+e^-$ linear colliders for the measurement of the
lifetime of a SM Higgs boson in the intermediate mass range are analysed. In
the $WW$ mode, the lifetime of Higgs scalars with masses below $\sim 160$ GeV
can be determined with an error less than 10%. The reconstruction of the Higgs
potential requires the measurement of the Higgs self-couplings. The SM and MSSM
trilinear Higgs self-couplings are accessible in double and triple Higgs
production. A theoretical analysis is presented in the relevant channels at the
LHC and $e^+e^-$ linear colliders. For high luminosities, the SM trilinear
Higgs self-coupling can be measured with an accuracy of 20% at a 500 GeV
$e^+e^-$ linear collider. The MSSM coupling among three light Higgs bosons has
to be extracted from continuum production. The other trilinear Higgs couplings
are measurable in a restricted range of the MSSM parameter space. At the LHC,
the $Hhh$ coupling can be probed in resonant decays.

</DOC>
<DOC>
<DOCNO> 83394 </DOCNO>
An improved parser for data-oriented lexical-functional analysis


  We present an LFG-DOP parser which uses fragments from LFG-annotated
sentences to parse new sentences. Experiments with the Verbmobil and Homecentre
corpora show that (1) Viterbi n best search performs about 100 times faster
than Monte Carlo search while both achieve the same accuracy; (2) the DOP
hypothesis which states that parse accuracy increases with increasing fragment
size is confirmed for LFG-DOP; (3) LFG-DOP's relative frequency estimator
performs worse than a discounted frequency estimator; and (4) LFG-DOP
significantly outperforms Tree-DOP is evaluated on tree structures only.

</DOC>
<DOC>
<DOCNO> 119466 </DOCNO>
UVES observations of QSO 0000-2620: oxygen and zinc abundances in the


  Observations of the QSO 0000-2620 with UVES spectrograph at the 8.2m ESO
KUEYEN telescope are used for abundance analysis of the damped Ly-alpha system
at z_{abs}=3.3901. Several Oxygen lines are identified in the Ly_alpha forest
and a measure for the oxygen abundance is obtained at [O/H]=-1.85 +/- 0.1 by
means of the unsaturated OI 925 A and OI 950 A lines. This represents the most
accurate O measurement in a damped Ly_alpha galaxy so far. We have also
detected ZnII 2026 A and CrII 2056, 2062 A redshifted at about 8900 A and found
abundances [Zn/H] = -2.07 +/- 0.1 and [Cr/H]=-1.99 +/- 0.1. Furthermore,
previous measurements of Fe, Si, Ni and N have been refined yielding
[Fe/H]=-2.04 +/- 0.1, [Si/H]=-1.90 +/- 0.1, [Ni/H]=-2.27 +/- 0.1, and
[N/H]=-2.68 +/- 0.1. The abundance of the non-refractory element zinc is the
lowest among the damped Ly-alpha systems showing that the associated
intervening galaxy is indeed in the early stages of its chemical evolution. The
fact that the Zn abundance is identical to that of the refractory elements Fe
and Cr suggests that dust grains have not formed yet. In this Damped Ly-alpha
system the observed [O,S,Si/Zn,Fe,Cr] ratios, in whatever combination are
taken, are close to solar (i.e 0.1-0.2 dex) and do not show the
[alpha-element/Fe] enhancement observed in Milky Way stars of comparable
metallicity. The observed behavior supports a galaxy evolution model
characterized by either episodic or low star formation rate rather than a
Milky-Way-type evolutionary model.

</DOC>
<DOC>
<DOCNO> 12501 </DOCNO>
A Lattice Gas Coupled to Two Thermal Reservoirs: Monte Carlo and Field


  We investigate the collective behavior of an Ising lattice gas, driven to
non-equilibrium steady states by being coupled to {\em two} thermal baths.
Monte Carlo methods are applied to a two-dimensional system in which one of the
baths is fixed at infinite temperature. Both generic long range correlations in
the disordered state and critical poperties near the second order transition
are measured. Anisotropic scaling, a key feature near criticality, is used to
extract $T_{c}$ and some critical exponents. On the theoretical front, a
continuum theory, in the spirit of Landau-Ginzburg, is presented. Being a
renormalizable theory, its predictions can be computed by standard methods of
$\epsilon $-expansions and found to be consistent with simulation data. In
particular, the critical behavior of this system belongs to a universality
class which is quite {\em different} from the uniformly driven Ising model.

</DOC>
<DOC>
<DOCNO> 102399 </DOCNO>
The infrared behaviour in Nelson's model of a quantum particle coupled


  We prove that Nelson's massless scalar field model is infrared divergent in
three dimensions. In particular, the Nelson Hamiltonian and the Hamiltonian
obtained from Euclidean quantization are not unitarily equivalent. In contrast,
for dimensions higher than three the Nelson Hamiltonian has a unique ground
state in Fock space and the two Hamiltonians are unitarily equivalent. We also
show that the Euclidean Hamiltonian has no spectral gap.

</DOC>
<DOC>
<DOCNO> 70785 </DOCNO>
Charmed baryons from lattice QCD


  The results of a recent quenched lattice QCD simulation for charmed baryons
are presented. In contrast to a previous calculation, it is found that
hyperfine splittings are in agreement with quark model expectations and
comparable to experimental values. Preliminary calculations using lattice NRQCD
yield results which are compatible with those obtained using a Dirac-Wilson
action of the D234 type for the charm quark.

</DOC>
<DOC>
<DOCNO> 101162 </DOCNO>
Some linear Jacobi structures on vector bundles


  We study Jacobi structures on the dual bundle $A^\ast$ to a vector bundle $A$
such that the Jacobi bracket of linear functions is again linear and the Jacobi
bracket of a linear function and the constant function 1 is a basic function.
We prove that a Lie algebroid structure on $A$ and a 1-cocycle $\phi \in \Gamma
(A^\ast)$ induce a Jacobi structure on $A^\ast$ satisfying the above
conditions. Moreover, we show that this correspondence is a bijection. Finally,
we discuss some examples and applications.

</DOC>
<DOC>
<DOCNO> 99406 </DOCNO>
An inequality for the norm of a polynomial factor


  Let $p(z)$ be a monic polynomial of degree $n$, with complex coefficients,
and let $q(z)$ be its monic factor. We prove an asymptotically sharp inequality
of the form $\|q\|_{E} \le C^n \|p\|_E$, where $\|\cdot\|_E$ denotes the sup
norm on a compact set $E$ in the plane. The best constant $C_E$ in this
inequality is found by potential theoretic methods. We also consider
applications of the general result to the cases of a disk and a segment.

</DOC>
<DOC>
<DOCNO> 84860 </DOCNO>
Conceptual Issues for Noncommutative Gravity on Algebras and Finite Sets


  We discuss some of the issues to be addressed in arriving at a definitive
noncommutative Riemannian geometry that generalises conventional geometry both
to the quantum domain and to the discrete domain. This also provides an
introduction to our 1997 formulation based on quantum group frame bundles. We
outline now the local formulae with general differential calculus both on the
base `quantum manifold' and on the structure group Gauge transforms with
nonuniversal calculi, Dirac operator, Levi-Civita condition, Ricci tensor and
other topics are also covered. As an application we outline an intrinsic or
relative theory of quantum measurement and propose it as a possible framework
to explore the link between gravity in quantum systems and entropy.

</DOC>
<DOC>
<DOCNO> 13035 </DOCNO>
Transitions of I- and II-order in magnetic field for superconducting


  Basing on self-consistent solution of non-linear GL-equations, the phase
boundary is found, which divides the regions of I- and II-order phase
transitions of a superconducting cylinder in magnetic field to normal state.
This boundary is a complicated function of the parameters (m,R,kappa) (m is the
vorticity, R is the cylinder radius, kappa is the GL-parameter), which does not
coincide with the simple phase boundary kappa=1/\sqrt{2}, dividing the regions
of I- and II-order phase transitions in infinite (open) superconducting
systems.

</DOC>
<DOC>
<DOCNO> 68659 </DOCNO>
The relevance of $\gamma_L^*$ in hard collisions of virtual photons


  We explore the relevance of extending the concept of the structure to the
longitudinally polarized virtual photon involved in hard collisions. We show
that for moderate photon virtualities and in the kinematical region accessible
in current experiments at HERA and LEP, the contributions of its longitudinal
polarization to hard collisions are sizable and should be taken into account as
part of the resolved photon component.

</DOC>
<DOC>
<DOCNO> 71437 </DOCNO>
Current Topics in B Physics


  I discuss topics of particular interest in connection with the ongoing
experiments at the B factories BaBar and Belle: B-mixing, QCD effects in
nonleptonic decays and rare decays.

</DOC>
<DOC>
<DOCNO> 10201 </DOCNO>
Finite Temperature Collapse of a Bose Gas with Attractive Interactions


  We study the mechanical stability of the weakly interacting Bose gas with
attractive interactions, and construct a unified picture of the collapse valid
from the low temperature condensed regime to the high temperature classical
regime. As we show, the non-condensed particles play a crucial role in
determining the region of stability, even providing a mechanism for collapse in
the non-condensed cloud. Furthermore, we demonstrate that the mechanical
instability prevents BCS-type ``pairing'' in the attractive Bose gas. We extend
our results to describe domain formation in spinor condensates.

</DOC>
<DOC>
<DOCNO> 83495 </DOCNO>
Kima - an Automated Error Correction System for Concurrent Logic


  We have implemented Kima, an automated error correction system for concurrent
logic programs. Kima corrects near-misses such as wrong variable occurrences in
the absence of explicit declarations of program properties. Strong
moding/typing and constraint-based analysis are turning to play fundamental
roles in debugging concurrent logic programs as well as in establishing the
consistency of communication protocols and data types. Mode/type analysis of
Moded Flat GHC is a constraint satisfaction problem with many simple mode/type
constraints, and can be solved efficiently. We proposed a simple and efficient
technique which, given a non-well-moded/typed program, diagnoses the
``reasons'' of inconsistency by finding minimal inconsistent subsets of
mode/type constraints. Since each constraint keeps track of the symbol
occurrence in the program, a minimal subset also tells possible sources of
program errors. Kima realizes automated correction by replacing symbol
occurrences around the possible sources and recalculating modes and types of
the rewritten programs systematically. As long as bugs are near-misses, Kima
proposes a rather small number of alternatives that include an intended
program.

</DOC>
<DOC>
<DOCNO> 102767 </DOCNO>
Invitation to higher local fields, Part I, section 2: p-primary part of


  For an arbitrary field p-torsion and cotorsion of the Milnor groups K_n(F)
and K_n^{t}(F)=K_n(F)/\cap_{l\ge1} lK_n(F) are discussed. The work contains
further discussions of an analogue of Satz 90 for K_n(F) and K_n^{t}(F) and
computation of H^{n+1}_m(F) where F is either the rational function field in
one variable F=k(t) or the formal power series F=k((t)).

</DOC>
<DOC>
<DOCNO> 121989 </DOCNO>
The KPNO International Spectroscopic Survey. II. H-alpha Selected Survey


  The KPNO International Spectroscopic Survey (KISS) is a new objective-prism
survey for extragalactic emission-line objects. It combines many of the
features of previous slitless spectroscopic surveys with the advantages of
modern CCD detectors, and is the first purely digital objective-prism survey
for emission-line galaxies. Here we present the first list of emission-line
galaxy candidates selected from our red spectral data, which cover the spectral
range 6400 to 7200 Angstroms. In most cases, the detected emission line is
H-alpha. The current survey list covers a one-degree-wide strip located at Dec
(1950) = 29.5 degrees and spanning the RA range 12h 15m to 17h 0m. An area of
62.2 sq. degrees is covered. A total of 1128 candidate emission-line objects
have been selected for inclusion in the survey list (18.1 per sq. degree). We
tabulate accurate coordinates and photometry for each source, as well as
estimates of the redshift and emission-line flux and equivalent width based on
measurements of the digital objective-prism spectra. The properties of the KISS
emission-line galaxies are examined using the available observational data.

</DOC>
<DOC>
<DOCNO> 116283 </DOCNO>
Tentative statistical interpretation of non-equilibrium entropy


  We suggest a certain statistical interpretation for the entropy produced in
driven thermodynamic processes. The exponential function of the irreversible
entropy re-weights the probability of the standard Ornstein-Uhlenbeck-type
thermodynamic fluctuations.

</DOC>
<DOC>
<DOCNO> 84231 </DOCNO>
Gravitational event search with five resonant antennas


  Five cryogenic resonant gravitational antennas are now in operation. This is
the first time that such a large number of high sensitive antennas are taking
data and an agreement on data exchange has been signed by the responsible
groups. The data exchanged will consist essentially in lists of ''candidate
events''. In this paper the procedure used by the Rome group in order to obtain
''candidate events'' is presented.
  Some methods of analyzing the data of the "network" of the five antennas are
shown.

</DOC>
<DOC>
<DOCNO> 150914 </DOCNO>
Irreducible Decomposition of Products of 10D Chiral Sigma Matrices


  We review the enveloping algebra of the 10 dimensional chiral sigma matrices.
To facilitate the computation of the product of several chiral sigma matrices
we have developed a symbolic program. Using this program one can reduce the
multiplication of the sigma matrices down to linear combinations of irreducilbe
elements. We are able to quickly derive several identities that are not
restricted to traces. A copy of the program written in the Mathematica language
is provided for the community.

</DOC>
<DOC>
<DOCNO> 69884 </DOCNO>
Possible textures of neutrino and charged lepton mass matrices


  We study a variety of different texture patterns in the basis in which the
charged lepton mass matrix or neutrino mass matrix or neither are diagonal. The
experimental results on the neutrinos provide sufficient restrictions to allow
only a small number of simple patterns. We discuss particularly the texture
zeroes which provide important relations among the mass eigenvalues and the
mixing matrix.

</DOC>
<DOC>
<DOCNO> 102582 </DOCNO>
Coherent states and the quantization of 1+1-dimensional Yang-Mills


  This paper discusses the canonical quantization of 1+1-dimensional Yang-Mills
theory on a spacetime cylinder, from the point of view of coherent states, or
equivalently, the Segal-Bargmann transform. Before gauge symmetry is imposed,
the coherent states are simply ordinary coherent states labeled by points in an
infinite-dimensional linear phase space. Gauge symmetry is imposed by
projecting the original coherent states onto the gauge-invariant subspace,
using a suitable regularization procedure. We obtain in this way a new family
of "reduced" coherent states labeled by points in the reduced phase space,
which in this case is simply the cotangent bundle of the structure group K.
   The main result explained here, obtained originally in a joint work of the
author with B. Driver, is this: The reduced coherent states are precisely those
associated to the generalized Segal-Bargmann transform for K, as introduced by
the author from a different point of view. This result agrees with that of K.
Wren, who uses a different method of implementing the gauge symmetry. The
coherent states also provide a rigorous way of making sense out of the quantum
Hamiltonian for the unreduced system.
   Various related issues are discussed, including the complex structure on the
reduced phase space and the question of whether quantization commutes with
reduction.

</DOC>
<DOC>
<DOCNO> 169968 </DOCNO>
Asymmetric quantum channel for quantum teleportation


  There are a few obstacles, which bring about imperfect quantum teleportation
of a continuous variable state, such as unavailability of maximally entangled
two-mode squeezed states, inefficient detection and imperfect unitary
transformation at the receiving station. We show that all those obstacles can
be understood by a combination of an {\it asymmetrically-decohered} quantum
channel and perfect apparatuses for other operations. For the
asymmetrically-decohered quantum channel, we find some counter-intuitive
results; one is that teleportation does not necessarily get better as the
channel is initially squeezed more and another is when one branch of the
quantum channel is unavoidably subject to some imperfect operations, blindly
making the other branch as clean as possible may not result in the best
teleportation result. We find the optimum strategy to teleport an unknown field
for a given environment or for a given initial squeezing of the channel.

</DOC>
<DOC>
<DOCNO> 151871 </DOCNO>
Covariant Quantization of the Brink-Schwarz Superparticle


  The quantization of the Brink-Schwarz-Casalbuoni superparticle is performed
in an explicitly covariant way using the antibracket formalism. Since an
infinite number of ghost fields are required, within a suitable off-shell
twistor-like formalism, we are able to fix the gauge of each ghost sector
without modifying the physical content of the theory. The computation reveals
that the antibracket cohomology contains only the physical degrees of freedom.

</DOC>
<DOC>
<DOCNO> 102098 </DOCNO>
Numerical Analysis of the Non-uniform Sampling Problem


  We give an overview of recent developments in the problem of reconstructing a
band-limited signal from non-uniform sampling from a numerical analysis view
point. It is shown that the appropriate design of the finite-dimensional model
plays a key role in the numerical solution of the non-uniform sampling problem.
In the one approach (often proposed in the literature) the finite-dimensional
model leads to an ill-posed problem even in very simple situations. The other
approach that we consider leads to a well-posed problem that preserves
important structural properties of the original infinite-dimensional problem
and gives rise to efficient numerical algorithms. Furthermore a fast multilevel
algorithm is presented that can reconstruct signals of unknown bandwidth from
noisy non-uniformly spaced samples. We also discuss the design of efficient
regularization methods for ill-conditioned reconstruction problems. Numerical
examples from spectroscopy and exploration geophysics demonstrate the
performance of the proposed methods.

</DOC>
<DOC>
<DOCNO> 99332 </DOCNO>
Stratification of the Generalized Gauge Orbit Space


  The action of Ashtekar's generalized gauge group $\Gb$ on the space $\Ab$ of
generalized connections is investigated for compact structure groups $\LG$.
  First a stratum is defined to be the set of all connections of one and the
same gauge orbit type, i.e. the conjugacy class of the centralizer of the
holonomy group. Then a slice theorem is proven on $\Ab$. This yields the
openness of the strata. Afterwards, a denseness theorem is proven for the
strata. Hence, $\Ab$ is topologically regularly stratified by $\Gb$. These
results coincide with those of Kondracki and Rogulski for Sobolev connections.
As a by-product, we prove that the set of all gauge orbit types equals the set
of all (conjugacy classes of) Howe subgroups of $\LG$. Finally, we show that
the set of all gauge orbits with maximal type has the full induced Haar measure
1.

</DOC>
<DOC>
<DOCNO> 11041 </DOCNO>
Ferromagnetism from Undressing


  We have recently proposed that superconductivity may be understood as driven
by the undressing of quasiparticles as the superconducting state develops.
Similarly we propose here that ferromagnetism in metals may be understood as
driven by the undressing of quasiparticles as the ferromagnetic state develops.
In ferromagnets, the undressing is proposed to occur due to the reduction in
$bond$ $charge$ caused by spin polarization, in contrast to superconductors
where the undressing is proposed to occur due to the reduction in $site$
$charge$ caused by (hole) pairing. The undressing process manifests itself in
the one and two-particle Green's functions as a transfer of spectral weight
from high to low frequencies. Hence it should have universal observable
consequences in one- and two-particle spectroscopies such as photoemission and
optical absorption.

</DOC>
<DOC>
<DOCNO> 9508 </DOCNO>
Interplay between Zeeman Coupling and Swap Action in Spin-based Quantum


  We consider theoretically the interplay between Zeeman coupling and
exchange-induced swap action in spin-based quantum dot quantum computer models
in the presence of inhomogeneous magnetic fields, which are invariably present
in real systems. We estimate quantitatively swap errors caused by the
inhomogeneous field, establishing that error correction would, in principle, be
possible in the presence of non-uniform magnetic fields in realistic
structures.

</DOC>
<DOC>
<DOCNO> 100473 </DOCNO>
Uniform Bounds and Symbolic Powers on Smooth Varieties


  We show how multiplier ideals can be used to obtain uniform multiplicative
bounds for certain families of ideals on a smooth complex algebraic variety. In
particular we prove a quick but rather surprising result about symbolic powers
of radical ideals on such a variety. Specifically, let I be a radical ideal
sheaf on a smooth variety X defining a reduced subscheme Z of X and suppose
that every irreducible component of Z has codimension at most e in X. Given an
integer m > 0 suppose that f is a function germ that vanishes to order at least
e.m at a general point of each irreducible component of Z . Then in fact f lies
in the m-th power I^m of I.

</DOC>
<DOC>
<DOCNO> 170331 </DOCNO>
Characterizing mixing and measurement in quantum mechanics


  What fundamental constraints characterize the relationship between a mixture
$\rho = \sum_i p_i \rho_i$ of quantum states, the states $\rho_i$ being mixed,
and the probabilities $p_i$? What fundamental constraints characterize the
relationship between prior and posterior states in a quantum measurement? In
this paper we show that there are many surprisingly strong constraints on these
mixing and measurement processes that can be expressed simply in terms of the
eigenvalues of the quantum states involved. These constraints capture in a
succinct fashion what it means to say that a quantum measurement acquires
information about the system being measured, and considerably simplify the
proofs of many results about entanglement transformation.

</DOC>
<DOC>
<DOCNO> 117351 </DOCNO>
The Central X-Ray Point Source in Cassiopeia A


  The spectacular first light observation by the Chandra X-Ray Observatory
revealed an X-ray point source near the center of the 300 yr old Cas A
supernova remnant. We present an analysis of the public X-ray spectral and
timing data. No coherent pulsations were detected in the Chandra/HRC data. The
3-sigma upper limit on the pulsed fraction is <35% for P>20 ms. The
Chandra/ACIS spectrum of the point source may be fit with an ideal blackbody
(kT=0.5 keV), or with BB models modified by the presence of a NS atmosphere
(kT=0.25-0.35 keV), but the temperature is higher and the inferred emitting
area lower than expected for a 300 yr old NS according to standard cooling
models. The spectrum may also be fit with a power law model (photon index
2.8-3.6). Both the spectral properties and the timing limits of the point
source are inconsistent with a young Crab-like pulsar, but are quite similar to
the properties of the anomalous X-ray pulsars. The spectral parameters are also
very similar to those of the other radio-quiet X-ray point sources in the
supernova remnants Pup A, RCW 103, and PKS 1209-52. Current limits on an
optical counterpart for the Cas A point source rule out models that invoke
fallback accretion onto a compact object if fallback disk properties are
similar to those in quiescent low-mass X-ray binaries. However, the optical
limits are marginally consistent with plausible alternative assumptions for a
fallback disk. In this case, accreting NS models can explain the X-ray data,
but an accreting BH model is not promising.

</DOC>
<DOC>
<DOCNO> 11823 </DOCNO>
Weak ferromagnetism and field-induced spin reorientation in K2V3O8


  Magnetization and neutron diffraction measurements indicate long-range
antiferromagnetic ordering below TN=4 K in the 2D, S=1/2 Heisenberg
antiferromagnet K2V3O8. The ordered state exhibits ``weak ferromagnetism'' and
novel, field-induced spin reorientations. These experimental observations are
well described by a classical, two-spin Heisenberg model incorporating
Dzyaloshinskii-Moriya interactions and an additional c-axis anisotropy. This
additional anisotropy can be accounted for by inclusion of the symmetric
anisotropy term recently described by Kaplan, Shekhtman, Entin-Wohlman, and
Aharony. This suggests that K2V3O8 may be a very unique system where the
qualitative behavior relies on the presence of this symmetric anisotropy.

</DOC>
<DOC>
<DOCNO> 101313 </DOCNO>
Infinite families of exact sums of squares formulas, Jacobi elliptic


  In this paper we derive many infinite families of explicit exact formulas
involving either squares or triangular numbers, two of which generalize
Jacobi's 4 and 8 squares identities to 4n^2 or 4n(n+1) squares, respectively,
without using cusp forms. In fact, we similarly generalize to infinite families
all of Jacobi's explicitly stated degree 2, 4, 6, 8 Lambert series expansions
of classical theta functions. In addition, we extend Jacobi's special analysis
of 2 squares, 2 triangles, 6 squares, 6 triangles to 12 squares, 12 triangles,
20 squares, 20 triangles, respectively. These results, depending on new
expansions for powers of various products of classical theta functions, arise
in the setting of Jacobi elliptic functions, associated continued fractions,
regular C-fractions, Hankel or Turanian determinants, Fourier series, Lambert
series, inclusion/exclusion, Laplace expansion formula for determinants, and
Schur functions. The Schur function form of these infinite families of
identities are analogous to the eta-function identities of Macdonald. Moreover,
the powers 4n(n+1), 2n^2+n, 2n^2-n that appear in Macdonald's work also arise
at appropriate places in our analysis. A special case of our general methods
yields a proof of the two Kac--Wakimoto conjectured identities involving
representing a positive integer by sums of 4n^2 or 4n(n+1) triangular numbers,
respectively.

</DOC>
<DOC>
<DOCNO> 152413 </DOCNO>
An AAD Model of Point Particle and the Pauli Equation


  The classical relativistic linear AAD interaction, introduced by the author,
leads in the case of weak coupling to a pointlike particle capable to be sub-
mitted to quantization via Feynman's path integrals along the line adequate to
the requirements of the Pauli equation. In the discussed nonrelativistic case
of the model the concept of spin is considered within early Feynman's ideas.

</DOC>
<DOC>
<DOCNO> 9080 </DOCNO>
On dispersive energy transport and relaxation in the hopping regime


  A new method for investigating relaxation phenomena for charge carriers
hopping between localized tail states has been developed. It allows us to
consider both charge and energy {\it dispersive} transport. The method is based
on the idea of quasi-elasticity: the typical energy loss during a hop is much
less than all other characteristic energies. We have investigated two models
with different density of states energy dependencies with our method. In
general, we have found that the motion of a packet in energy space is affected
by two competing tendencies. First, there is a packet broadening, i.e. the
dispersive energy transport. Second, there is a narrowing of the packet, if the
density of states is depleting with decreasing energy. It is the interplay of
these two tendencies that determines the overall evolution. If the density of
states is constant, only broadening exists. In this case a packet in energy
space evolves into Gaussian one, moving with constant drift velocity and mean
square deviation increasing linearly in time. If the density of states depletes
exponentially with decreasing energy, the motion of the packet tremendously
slows down with time. For large times the mean square deviation of the packet
becomes constant, so that the motion of the packet is ``soliton-like''.

</DOC>
<DOC>
<DOCNO> 150612 </DOCNO>
Vacuum polarization for neutral particles in 2+1 dimensions


  In 2+1 dimensions there exists a duality between a charged Dirac particle
coupled minimally to a background vector potential and a neutral one coupled
nonminimally to a background electromagnetic field strength. A constant uniform
background electric current induces in the vacuum of the neutral particle a
fermion current which is proportional to the background one. A background
electromagnetic plane wave induces no current in the vacuum. For constant but
nonuniform background electric charge, known results for charged particles can
be translated to give the induced fermion number. Some new examples with
infinite background electric charge are presented. The induced spin and total
angular momentum are also discussed.

</DOC>
<DOC>
<DOCNO> 69586 </DOCNO>
Velocity distributions and annual-modulation signatures of


  An annual modulation in the event rate of the NaI detector of the DAMA
collaboration has been used to infer the existence of particle dark matter in
the Galactic halo. Bounds on the WIMP mass and WIMP-nucleon cross section have
been derived. These analyses have assumed that the local dark-matter velocity
distribution is either isotropic or has some bulk rotation. Here we consider
the effects of possible structure in the WIMP velocity distribution on the
annual-modulation amplitude. We show that if we allow for a locally anisotropic
velocity dispersion tensor, the interpretation of direct detection experiments
could be altered significantly. We also show that uncertainties in the velocity
distribution that arise from uncertainties in the radial density profile are
less important if the velocity dispersion is assumed to be isotropic.

</DOC>
<DOC>
<DOCNO> 119394 </DOCNO>
Interpretation of the Spatial Power Spectra of Neutral Hydrogen in the


  Recent 21 cm radio observations of H$_I$ regions in the Small Magellanic
Cloud, have revealed spatial power spectra of the intensity, which are quite
similar in shape to those previously deduced for the Galaxy. The similarity, in
spite the differences in the physical parameters between the Galaxy and the
SMC, suggests that the shape of the power spectra reflects some underlying
mechanism which is not too sensitive to the environmental specifics. In this
paper we present an interpretation for the observational power spectra in terms
of a large scale turbulence in the interstellar medium, in which the emitting
H$_I$ regions are embedded. The turbulence gives rise to density fluctuations
which lead to the observed intensity fluctuations, in the H$_I$ regions. The
observational power spectra are used to deduce the turbulence spectral
function.
 In the SMC, the turbulence largest eddies are comparable in scale to the SMC
itself. This implies that turbulent mixing should have smoothed out any large
scale abundance gradients. Indeed, this seems to be the case, observationally.
  The turbulence is also expected to amplify and shape up the large scale
magnetic field. Indeed, the observational data indicate the existence of a
large scale disordered field of the strength expected from energy equilibrium
with the turbulent velocity field. The large scale turbulence is most probably
generated by instabilities in the large scale flows induced by the tidal close
encounter with the LMC $ \sim 2\times 10^8{\rm yr}$ ago. The life-time of the
largest eddies is $\sim 4\times 10^8{\rm yr}$ so the turbulence had not yet
enough time to decay and persists even though the energy source is no longer
there.

</DOC>
<DOC>
<DOCNO> 170548 </DOCNO>
Quantum dynamical properties of a two-photon non-linear Jaynes-Cummings


  In this paper we study a two-photon time-dependent Jaynes-Cummings model
interacting with a Kerr-like medium. We assumed that the electromagnetic field
is in different states such as coherent, squeezed vacuum and pair coherent, and
that the atom is initially in the excited state. We studied the temporal
evolution of the population of the excited level, and the second order
coherence function. The results obtained show that this system has some
similarities with the two-mode Stark system. We analize two photon entanglement
for different initial conditions.

</DOC>
<DOC>
<DOCNO> 101869 </DOCNO>
The zeta(2) limit in the random assignment problem


  The random assignment (or bipartite matching) problem studies the random
total cost A_n of the optimal assignment of each of n jobs to each of n
machines, where the costs of the n^2 possible job-machine matches has
exponential (mean 1) distribution. Mezard - Parisi (1987) used the replica
method from statistical physics to argue non-rigorously that EA_n converges to
zeta(2) = pi^2/6. Aldous (1992) identified the limit as the optimal solution of
a matching problem on an infinite tree. Continuing that approach, we construct
the optimal matching on the infinite tree. This yields a rigorous proof of the
zeta(2) limit and of the conjectured limit distribution of edge-costs and their
rank-orders in the optimal matching.

</DOC>
<DOC>
<DOCNO> 67976 </DOCNO>
One-Loop Self Energy and Renormalization of the Speed of Light for some


  One-loop corrections to the fermion rest mass M_1, wave function
renormalization Z_2 and speed of light renormalization C_0 are presented for
lattice actions that combine improved glue with clover or D234 quark actions
and keep the temporal and spatial lattice spacings, a_t and a_s, distinct. We
explore a range of values for the anisotropy parameter \chi = a_s/a_t and treat
both massive and massless fermions.

</DOC>
<DOC>
<DOCNO> 70471 </DOCNO>
Active-Sterile Neutrino Transformation and r-Process Nucleosynthesis


  The type II supernova is considered as a candidate site for the production of
heavy elements. Since the supernova produces an intense neutrino flux, neutrino
scattering processes will impact element formation. We examine active-sterile
neutrino conversion in this environment and find that it may help to produce
the requisite neutron-to-seed ratio for synthesis of the r-process elements.

</DOC>
<DOC>
<DOCNO> 121682 </DOCNO>
Radio Properties of REX BL Lacs and Galaxies


  Detailed VLA observations have been gathered for a number of sources
classified as either BL Lacs or galaxies, derived from the REX survey. We focus
in particular on the sources identified by us, for which we have in hand
homogeneous optical data, to study in more detail than allowed by the NVSS the
radio properties of these sources in the framework of AGN unified models.

</DOC>
<DOC>
<DOCNO> 70345 </DOCNO>
NRQCD Analysis of Bottomonium Production at the Tevatron


  Recent data from the CDF collaboration on the production of spin-triplet
bottomonium states at the Tevatron p \bar p collider are analyzed within the
NRQCD factorization formalism. The color-singlet matrix elements are determined
from electromagnetic decays and from potential models. The color-octet matrix
elements are determined by fitting the CDF data on the cross sections for
Upsilon(1S), Upsilon(2S), and Upsilon(3S) at large p_T and the fractions of
Upsilon(1S) coming from chi_b(1P) and chi_b(2P). We use the resulting matrix
elements to predict the cross sections at the Tevatron for the spin-singlet
states eta_b(nS) and h_b(nP). We argue that eta_b(1S) should be observable in
Run II through the decay eta_b -> J/psi + J/psi.

</DOC>
<DOC>
<DOCNO> 122601 </DOCNO>
Stellar Population analysis from Broad-Band Colours


  We have developed an analytical method to investigate the stellar populations
in a galaxy using the broad-band colours. The method enables us to determine
the relative contribution, spatial distribution and age for different stellar
populations and gives a hint about the dust distribution in a galaxy. We apply
this method to the irregular galaxy NGC 3077, using CCD images in U, B, V and R
filters.

</DOC>
<DOC>
<DOCNO> 152511 </DOCNO>
The Kaluza-Klein Melvin Solution in M-theory


  We study some aspects of the Kaluza-Klein Melvin solution in M-theory. The
associated magnetic field has a maximal critical value $B=\pm 1/R$ where $R$ is
the radius of the compactification circle. It is argued that the Melvin
background of type IIA with magnetic field $B$ and of type 0A with magnetic
field $B'=B-1/R$ are equivalent. Evidence for this conjecture is provided using
a further circle compactification and a `9-11' flip. We show that partition
functions of nine-dimensional type IIA strings and of a $(-1)^F\sigma_{1/2}$
type IIA orbifold both with NS-NS Melvin fluxtubes are related by such shift of
the magnetic field. Then the instabilities of both IIA and 0A Melvin solutions
are analyzed. For each theory there is an instanton associated to the decay of
spacetime. In the IIA case the decay mode is associated to the nucleation of
$D6/D\bar{6}$-brane pairs, while in the 0A case spacetime decays through
Witten's bubble production.

</DOC>
<DOC>
<DOCNO> 101159 </DOCNO>
Minimal Lagrangian tori in Kahler Einstein manifolds


  In this paper we use structure preserving torus actions on Kahler-Einstein
manifolds to construct minimal Lagrangian submanifolds. Our main result is: Let
N^2n be a Kahler-Einstein manifold with positive scalar curvature with an
effective T^n-action. Then precisely one regular orbit L of the T-action is a
minimal Lagrangian submanifold of N. Moreover there is an (n-1)-torus T^n-1 in
T^n and a sequence of non-flat immersed minimal Lagrangian tori L_k in N,
invariant under T^n-1 s.t. L_k locally converge to L (in particular the
supremum of the sectional curvatures of L_k and the distance between L_k and L
go to 0 as k goes to infinity.

</DOC>
<DOC>
<DOCNO> 13739 </DOCNO>
Tribological Behavior of Very Thin Confined Films


  The tribological properties of two smooth surfaces in the presence of a thin
confined film are investigated with a generic model for the interaction between
two surfaces and with computer simulations. It is shown that at large normal
contact pressures, an ultra thin film automatically leads to static friction
between two flat surfaces - even if the surfaces are incommensurate.
Commensurability is nevertheless the key quantity to understand the
tribological behavior of the contact. Qualitative differences between
commensurate and incommensurate contacts remain even in the presence of a thin
film. The differences mainly concern the thermal diffusion of the contact and
the transition between smooth sliding and stick-slip.

</DOC>
<DOC>
<DOCNO> 119980 </DOCNO>
Sub-mm and X-ray background: two unrelated phenomena?


  Obscured AGNs are thought to contribute a large fraction of the hard X-ray
background (2-10 keV), and have also been proposed as the powerhouse of a
fraction of the SCUBA sources which make most of the background at 850um, thus
providing a link between the two spectral windows. We have tackled this issue
by comparing data at 2-10 keV and at 850um for a sample of 34 sources at fluxes
(or limiting fluxes) which resolve most of the background in the two bands. We
present here new SCUBA observations, and new correlations between separate data
sets retrieved from the literature. Similar correlations presented by others
are added for completeness. None of the 11 hard X-ray (2-10 keV) sources has a
counterpart at 850um, with the exception of a Chandra source in the SSA13
field, which is a candidate type 2, heavily absorbed QSO at high redshift. The
ratios F(850um)/F(5keV) (mostly upper limits) of the X-ray sources are
significantly lower than the value observed for the cosmic background. In
particular, we obtain that 2-10 keV sources brighter than 10^-15 erg s^-1
cm^-2, which make at least 75% of the background in this band, contribute for
less than 7% to the submillimeter background. Out of the 24 SCUBA sources, 23
are undetected by Chandra. The ratios F(850um)/F(5keV) (mostly lower limits) of
these SCUBA sources indicate that most of them must be powered either by
starburst activity, or by an AGN which is obscured by a column Nh > 10^25
cm^-2, with a reflection efficiency in the hard X rays significantly lower than
1% in most cases. However, AGNs of this type could not contribute significantly
to the 2-10 keV background.

</DOC>
<DOC>
<DOCNO> 170622 </DOCNO>
Absorption by cold Fermi atoms in a harmonic trap


  We study the absorption spectrum for a strongly degenerate Fermi gas confined
in a harmonic trap. The spectrum is calculated using both the exact summation
and also the Thomas-Fermi (TF) approximation. In the latter case, relatively
simple analytical expressions are obtained for the absorption lineshape at
large number of trapped atoms. At zero temperature, the approximated lineshape
is characterized by a $(1-z^2)^{5/2}$ dependence which agrees well with the
exact numerical calculations. At non-zero temperature, the spectrum becomes
broader, although remains non-Gaussian as long as the fermion gas is
degenerate. The changes in the trap frequency for an electronically excited
atom can introduce an additional line broadening.

</DOC>
<DOC>
<DOCNO> 118175 </DOCNO>
The CDS information hub


  The Centre de Donnees astronomiques de Strasbourg (CDS) provides homogeneous
access to heterogeneous information of various origins: information about
astronomical objects in Simbad; catalogs and observation logs in VizieR and in
the catalogue service; reference images and overlays in Aladin; nomenclature in
the Dictionary of Nomenclature; Yellow Page services; the AstroGLU resource
discovery tool; mirror copies of other reference services; and documentation.
With the implementation of links between the CDS services, and with other
on--line reference information, CDS has become a major hub in the rapidly
evolving world of information retrieval in astronomy, developing efficient
tools to help astronomers to navigate in the world-wide `Virtual Observatory'
under construction, from data in the observatory archives to results published
in journals. The WWW interface to the CDS services is available at:
http://cdsweb.u-strasbg.fr/

</DOC>
<DOC>
<DOCNO> 7942 </DOCNO>
Evidence from $^{77}$Se Knight shifts for triplet superconductivity in


  The layered quasi-one-dimensional molecular superconductor (TMTSF)$_2$PF$_6$
is a very exotic material with a superconducting order parameter whose ground
state symmetry has remained ill-defined. Here we present a pulsed NMR Knight
shift (K) study of $^{77}$Se measured simultaneously with transport in
pressurized (TMTSF)$_2$PF$_6$. The Knight shift is linearly dependent on the
electron spin susceptibility $\chi_s$, and is therefore a direct measure of the
spin polarization in the superconducting state. For a singlet superconductor,
the spin contribution to the Knight shift, K$_s$, falls rapidly on cooling
through the transition. The present experiments indicate no observable change
in K between the metallic and superconducting states, and thus strongly support
the hypothesis of triplet p-wave superconductivity in (TMTSF)$_2$PF$_6$.

</DOC>
<DOC>
<DOCNO> 68683 </DOCNO>
Constraints on the CKM Angle $\gamma$ and Strong Phases from $B\to\pi K$


  As we pointed out recently, the neutral decays $B_d\to\pi^\mp K^\pm$ and
$B_d\to\pi^0K$ may provide non-trivial bounds on the CKM angle $\gamma$. In
this paper, we reconsider this approach in the light of recent CLEO data, which
look very interesting. In particular, the results for the corresponding
CP-averaged branching ratios are in favour of strong constraints on $\gamma$,
where the second quadrant is preferred. Such a situation would be in conflict
with the standard analysis of the unitarity triangle. Moreover, constraints on
a CP-conserving strong phase $\delta_n$ are in favour of a negative value of
$\cos\delta_n$, which would be in conflict with the factorization expectation.
In addition, there seems to be an interesting discrepancy with the bounds that
are implied by the charged $B\to\pi K$ system: whereas these decays favour a
range for $\gamma$ that is similar to that of the neutral modes, they point
towards a positive value of $\cos\delta_c$, which would be in conflict with the
expectation of equal signs for $\cos\delta_n$ and $\cos\delta_c$. If future
data should confirm this ``puzzle'', it may be an indication for new-physics
contributions to the electroweak penguin sector, or a manifestation of large
non-factorizable SU(3)-breaking effects.

</DOC>
<DOC>
<DOCNO> 150320 </DOCNO>
Collapsing D-Branes in Calabi-Yau Moduli Space: I


  We study the quantum volume of D-branes wrapped around various cycles in
Calabi-Yau manifolds, as the manifold's moduli are varied. In particular, we
focus on the behaviour of these D-branes near phase transitions between
distinct low energy physical descriptions of the resulting string theory.
Whereas previous studies have solely considered quantum volumes in the context
of two-cycles in perturbative string theory or D-branes in the specific example
of the quintic hypersurface, we work more generally and find qualitatively new
features. On the mathematical side, as we briefly note, our work has some
interesting implications for certain issues in arithmetics.

</DOC>
<DOC>
<DOCNO> 69368 </DOCNO>
A non-singular infra-red flow from D=5 gauged supergravity


  We discuss domain wall solutions of 5-dimensional supergravity corresponding
to a cosine-superpotential, which is derived by a gauging of the two Abelian
isometries of the scalar coset SU(2,1)/U(2). We argue that this potential can
be obtained from M-theory compactification in the presence of G-fluxes and an
M5-brane instanton gas. If we decouple the volume scalar of the internal space,
the superpotential allows for two extrema, which are either ultra-violet or
infra-red attractive. Asymptotically we approach therefore either the boundary
or the Killing horizon of an anti-deSitter space or flat spacetime for a
vanishing cosmological constant. If the volume scalar does not decouple, we
obtain a run-away potential corresponding to dilatonic domain walls, which
always run towards a vanishing cosmological constant.

</DOC>
<DOC>
<DOCNO> 152485 </DOCNO>
Fine-Tuning of the Cosmological Constant in Brane Worlds


  We discuss how the fine-tuning of the cosmological constant enters brane
world setups. After presenting the Randall Sundrum model as a prototype case,
we focus on single brane models with curvature singularities which are
separated from the brane in the additional dimension. Finally, the issue of the
existence of nearby curved solutions is addressed.

</DOC>
<DOC>
<DOCNO> 8922 </DOCNO>
Time relaxation of microwave second order response of superconductors in


  Relaxation of the microwave second order response of YBa2Cu3O7 and
Ba0.6K0.4BiO3 crystals in the critical state is studied. The samples are
exposed to static and pulsed microwave magnetic fields. The second harmonic
signals decay during the time in which the microwave pulse endures. The decay
times depend on the supercon-ductor investigated and on the way the value of
the static field has been reached.

</DOC>
<DOC>
<DOCNO> 8440 </DOCNO>
Magnetic properties of frustrated spin ladder


  The magnetic properties of the antiferromagnetic spin ladder with the
next-nearest neighbor interaction, particularly under external field, are
investigated by the exact diagonalization of the finite clusters and size
scaling techniques. It is found that there exist two phases, the rung-dimer and
rung-triplet phases, not only in the nonmagnetic ground state but also
magnetized one, where the phase boundary has a small magnetization dependence.
Only in the former phase, the magnetization curve is revealed to have a
possible plateau at half the saturation moment, with a sufficient frustration.

</DOC>
<DOC>
<DOCNO> 150317 </DOCNO>
Supersymmetry and Bogomol'nyi equations in the Maxwell Chern-Simons


  We take advantage of the superspace formalism and explicitly find the N=2
supersymmetric extension of the Maxwell Chern-Simons model. In our construction
a special form of a potential term and indispensability of an additional
neutral scalar field arise naturally. By considering the algebra of
supersymmetric charges we find Bogomol'nyi equations for the investigated
model.

</DOC>
<DOC>
<DOCNO> 67951 </DOCNO>
Signatures of galactic magnetic lensing upon ultra high energy cosmic


  We analyse several implications of lensing by the regular component of the
galactic magnetic field upon the observed properties of ultra high energy
cosmic rays. Magnetic fields deflect cosmic ray trajectories, causing flux
(de)magnification, formation of multiple images of a single source, and time
delays. We derive the energy dependence of these effects near the caustics at
which the flux amplification of a point source diverges. We show that the large
magnification of images around caustics leads to an amplification bias, which
can make them dominate the flux in some energy ranges. We argue that clustering
in the arrival directions of UHECRs of comparable energy may be due to magnetic
lensing around caustics. We show that magnetic lensing can also significantly
alter the observed composition of cosmic rays at the highest energies. We also
show that the time delay between events from a single image may monotonically
decrease with decreasing energy in the neighborhood of a caustic, opposite to
its behaviour in normal regions.

</DOC>
<DOC>
<DOCNO> 102262 </DOCNO>
Scattering on stratified media: the micro-local properties of the


  The fixed energy scattering matrix is defined on a perturbed stratified
medium, and for a class of perturbations, its main part is shown to be a
Fourier integral operator on the sphere at infinity. This is facilitated by
developing a refined limiting absorption principle. The symbol of the
scattering matrix is shown to determine the asymptotics of a large class of
perturbations.

</DOC>
<DOC>
<DOCNO> 68656 </DOCNO>
Fermion masses in a model for spontaneous parity breaking


  In this paper we discuss a left-right symmetric model for elementary
particles and their connection with the mass spectrum of elementary fermions.
The model is based on the group $SU(2)_L\otimes SU(2)_R\otimes U(1)$. New
mirror fermions and a minimal set of Higgs particles that breaks the symmetry
down to $U(1)_{em}$ are proposed. The model can accommodate a consistent
pattern for charged and neutral fermion masses as well as neutrino
oscillations. An important consequence of the model is that the connection
between the left and right sectors can be done by the neutral vector gauge
bosons Z and a new heavy Z'.

</DOC>
<DOC>
<DOCNO> 100382 </DOCNO>
Computing Complex Dimension Faster and Deterministically


  We give a new complexity bound for calculating the complex dimension of an
algebraic set. Our algorithm is completely deterministic and approaches the
best recent randomized complexity bounds. We also present some new,
significantly sharper quantitative estimates on rational univariate
representations of roots of polynomial systems. As a corollary of the latter
bounds, we considerably improve a recent algorithm of Koiran for deciding the
emptiness of a hypersurface intersection over the complex numbers, given the
truth of the Generalized Riemann Hypothesis (GRH).

</DOC>
<DOC>
<DOCNO> 12409 </DOCNO>
Nonadiabatic extension of the Heisenberg model


  The localized states within the Heisenberg model of magnetism should be
represented by best localized Wannier functions forming a unitary
transformation of the Bloch functions of the narrowest partly filled energy
bands in the metals. However, as a consequence of degeneracies between the
energy bands near the Fermi level, in any metal these Wannier functions cannot
be chosen symmetry-adapted to the complete paramagnetic group M^P. Therefore,
it is proposed to use Wannier functions with the reduced symmetry of a magnetic
subgroup M of M^P [case (a)] or spin dependent Wannier functions [case (b)].
The original Heisenberg model is reinterpreted in order to understand the
pronounced symmetry of these Wannier functions. While the original model
assumes that there is exactly one electron at each atom, the extended model
postulates that in narrow bands there are as many as possible atoms occupied by
exactly one electron. However, this state with the highest possible atomiclike
character cannot be described within the adiabatic (or Born-Oppenheimer)
approximation because in the (true) nonadiabatic system the electrons move on
localized orbitals that are still symmetric on the average of time, but not at
any moment. The nonadiabatic states have the same symmetry as the adiabatic
states and determine the commutation properties of the nonadiabatic Hamiltonian
H^n. The nonadiabatic Heisenberg model is a purely group- theoretical model
which interprets the commutation properties of H^n that are explicitly given in
this paper for the two important cases (a) and (b). There is evidence that the
occurrence of these two types of Wannier functions in the band structure of a
metal is connected with the occurrence of magnetism and superconductivity,
respectively.

</DOC>
<DOC>
<DOCNO> 119626 </DOCNO>
ORFEUS II echelle spectra : H_2 measurements in the Magellanic Clouds


  More than 20 years after the Copernicus satellite, ORFEUS allows the
investigation of molecular hydrogen (H_2) in the diffuse interstellar medium by
way of FUV absorption spectroscopy once again. This time, targets in the
Magellanic Clouds were also observed, allowing the first investigation of cold
H_2 in a metal-poor environment outside the Milky Way disk. This paper presents
new H_2 measurements in LMC gas along the lines of sight toward HD 269698 (Sk
67 166), HD 269546 (Sk -68 82) and HD 36402 (Sk 67 104) and summarizes the
ORFEUS H_2 measurements in the the Magellanic Clouds. For seven lines of sight
we investigate correlations between N(H I), N(H_2), E(B-V) and compare the
results with H_2 observations in the Milky Way disk. We find that the abundance
of H_2 is low in comparison to the total gas quantity and speculate that the
fraction of hydrogen in molecular form is limited by the lower dust content of
the Magellanic Clouds.

</DOC>
<DOC>
<DOCNO> 118459 </DOCNO>
A ROSAT HRI study of the open cluster NGC 3532


  NGC 3532 is a very rich southern open cluster of age ~200-350 Myr; it is
therefore a good candidate to investigate the X-ray activity-age-rotation
relationship at ages intermediate between the Pleiades and the Hyades, where,
to our knowledge, X-rays studies exist for only one cluster (NGC 6475). We have
performed an X-ray study of NGC 3532 using HRI observations retrieved from the
ROSAT archive. The observations have a limiting sensitivity $L_{\mathrm x} \sim
4 \times 10^{28}$ erg sec$^{-1}$ in the center of the field. We detected ~50
X-ray sources above a $4 \sigma$ threshold, half of which have a known optical
counterpart within 10 arcsec; 15 of the X-ray sources have at least one cluster
member as optical counterpart.
  A comparison of NGC 3532 with the nearly coeval cluster NGC 6475 indicates
that the former cluster is considerably X-ray underluminous with respect to NGC
6475. However, because of the existence of possible selection effects,
additional X-ray and optical observations are needed before definitively
concluding that the X-ray properties of NGC 3532 and NGC 6475 are significantly
different.

</DOC>
<DOC>
<DOCNO> 100631 </DOCNO>
The Chow groups and the motive of the Hilbert scheme of points on a


  We compute the Chow motive and the Chow groups with rational coefficients of
the Hilbert scheme of points on a smooth algebraic surface

</DOC>
<DOC>
<DOCNO> 12728 </DOCNO>
Speculative bubbles and crashes in stock market: an interacting-agent


  We present an interacting-agent model of speculative activity explaining
bubbles and crashes in stock markets. We describe stock markets through an
infinite-range Ising model to formulate the tendency of traders getting
influenced by the investment attitude of other traders. Bubbles and crashes are
understood and described qualitatively and quantitatively in terms of the
classical phase transitions. The results of estimation the parameters of the
model using the actual financial data (the bubble and the subsequent crash in
the Japanese stock market in 1987-1992) show that the good quality of the fits,
as well as the consistency of the values of the parameters.

</DOC>
<DOC>
<DOCNO> 71738 </DOCNO>
Challenges in Hyperon Decays


  We give an personal overview of some of the unsolved problems related to
hyperon decays. We cover nonleptonic decays, radiative decays and magnetic
moments. Some of the theoretical issues are also touched upon.

</DOC>
<DOC>
<DOCNO> 99956 </DOCNO>
Relations among divisors on the moduli space of curves with marked


  We prove relations among the classes of certain divisors on the moduli spaces
of curves with marked points, generalizing the Brill-Noether Ray Theorem of
Eisenbud and Harris.

</DOC>
<DOC>
<DOCNO> 121088 </DOCNO>
VSOP observation of the quasar PKS 2215+020: a new laboratory for


  We report results of a VSOP (VLBI Space Observatory Programme) observation of
a high redshift quasar PKS 2215+020 (z=3.572). The ~1 milliarcsecond resolution
image of the quasar reveals a prominent `core-jet' structure on linear scales
from 5/h to 300/h pc ($H_0=100*h km/(s*Mpc). The brightness temperatures and
sizes of bright features identified in the jet are consistent with emission
from relativistic shocks dominated by adiabatic energy losses. The jet is
powered by the central black hole with estimated mass of ~4*10^9 solar masses.
Comparisons with VLA and ROSAT observations indicate a possible presence of an
extended radio/X-ray halo surrounding 2215+020.

</DOC>
<DOC>
<DOCNO> 151005 </DOCNO>
The Tachyon Potential in Witten's Superstring Field Theory


  We study the tachyon potential in the NS sector of Witten's cubic superstring
field theory. In this theory, the pure tachyon contribution to the potential
has no minimum. We find that this remains the case when higher modes up to
level two are included.

</DOC>
<DOC>
<DOCNO> 8649 </DOCNO>
Tight-Binding Linear Scaling Method Applications to Silicon Surfaces


  The past years have witnessed impressive advances in electronic structure
calculation, especially in the complexity and size of the systems studied, as
well as in computation time. Linear scaling methods based on empirical
tight-binding Hamiltonians which can describe chemical bonding, and have a
computational time proportional to the number of atoms N in the system, are of
particular interest for simulations in material science. By contrast
conventional diagonalization schemes scale as $N^{3}$. In combination with
judiciously fitted parameters and an implementation suited for MD, it is
possible to apply such \emph{O(N)} methods to structural, electronic and
dynamical properties of large systems which include up to 1000 atoms on a
workstation.
  Following a brief review of a tight-binding based linear-scaling method based
on a local orbital formulation and of parametrizations appropriate for
covalently bonded systems, we present recent test calculations on
\emph{Si(111)-5 $\times$}5 and \emph{Si(001)-c(4$\times$}2) reconstructed
surfaces in this framework, and compare our results with previous tight-binding
and \emph{ab-initio} calculations.

</DOC>
<DOC>
<DOCNO> 70893 </DOCNO>
Neutrino emission due to Cooper pairing of protons in cooling neutron


  The process of neutrino-pair radiation due to formation and breaking of
Cooper pairs of protons in superconducting cores of neutron stars is considered
with taking into account of the electromagnetic coupling of protons to ambient
electrons. It is shown that plasma polarization strongly modifies the effective
vector weak current of protons. Collective response of ambient electrons to the
proton quantum transition contributes coherently to the complete interaction
with the neutrino field and enhances the rate of neutrino-pair production by
two orders of magnitude.

</DOC>
<DOC>
<DOCNO> 83432 </DOCNO>
Super Logic Programs


  The Autoepistemic Logic of Knowledge and Belief (AELB) is a powerful
nonmonotic formalism introduced by Teodor Przymusinski in 1994. In this paper,
we specialize it to a class of theories called `super logic programs'. We argue
that these programs form a natural generalization of standard logic programs.
In particular, they allow disjunctions and default negation of arbibrary
positive objective formulas.
  Our main results are two new and powerful characterizations of the static
semant ics of these programs, one syntactic, and one model-theoretic. The
syntactic fixed point characterization is much simpler than the fixed point
construction of the static semantics for arbitrary AELB theories. The
model-theoretic characterization via Kripke models allows one to construct
finite representations of the inherently infinite static expansions.
  Both characterizations can be used as the basis of algorithms for query
answering under the static semantics. We describe a query-answering interpreter
for super programs which we developed based on the model-theoretic
characterization and which is available on the web.

</DOC>
<DOC>
<DOCNO> 101935 </DOCNO>
Stable identification of piecewise-constant potentials from fixed-energy


  An identification of a spherically symmetric potential by its phase shifts is
an important physical problem. Recent theoretical results assure that such a
potential is uniquely defined by a sufficiently large subset of its phase
shifts at any one fixed energy level. However, two different potentials can
produce almost identical phase shifts. That is, the inverse problem of the
identification of a potential from its phase shifts at one energy level $k^2$
is ill-posed, and the reconstruction is unstable. In this paper we introduce a
quantitative measure $D(k)$ of this instability. The diameters of minimizing
sets
 $D(k)$ are used to study the change in the stability with the change of $k$,
and the influence of noise on the identification. They are also used in the
stopping criterion for the nonlinear minimization method IRRS (Iterative Random
Reduced Search). IRRS combines probabilistic global and deterministic local
search methods and it is used for the numerical recovery of the potential by
the set of its phase shifts. The results of the identification for noiseless as
well as noise corrupted data are presented.

</DOC>
<DOC>
<DOCNO> 119382 </DOCNO>
Halo occupation numbers and galaxy bias


  We propose a heuristic model that displays the main features of realistic
theories for galaxy bias. We show that the low-order clustering statistics of
the dark-matter distribution depend almost entirely on the locations and
density profiles of dark-matter haloes. A hypothetical galaxy catalogue depends
on (i) the efficiency of galaxy formation, as manifested by the halo occupation
number -- the number of galaxies brighter than some sample limit contained in a
halo of a given mass; (ii) the location of these galaxies within their halo.
The first factor is constrained by the empirical luminosity function of groups.
For the second factor, we assume that one galaxy marks the halo centre, with
any remaining galaxies acting as satellites that trace the halo mass. These
simple assumptions amount to a recipe for non-local bias, in which the
probability of finding a galaxy is not a simple function of its local mass
density. We have applied this prescription to some CDM models of current
interest, and find that the predictions are close to the observed galaxy
correlations for a flat $\Omega=0.3$ model ($\Lambda$CDM), but not for an
$\Omega=1$ model with the same power spectrum ($\tau$CDM). This is an
inevitable consequence of cluster normalization for the power spectra:
cluster-scale haloes of given mass have smaller core radii for high $\Omega$,
and hence display enhanced small-scale clustering. Finally, the pairwise
velocity dispersion of galaxies in the $\Lambda$CDM model is lower than that of
the mass, allowing cluster-normalized models to yield a realistic Mach number
for the peculiar velocity field. This is largely due to the strong variation of
galaxy-formation efficiency with halo mass that is required in this model.

</DOC>
<DOC>
<DOCNO> 12953 </DOCNO>
Measuring non-extensitivity parameters in a turbulent Couette-Taylor


  We investigate probability density functions of velocity differences at
different distances r measured in a Couette-Taylor flow for a range of Reynolds
numbers Re. There is good agreement with the predictions of a theoretical model
based on non-extensive statistical mechanics (where the entropies are
non-additive for independent subsystems). We extract the scale-dependent
non-extensitivity parameter q(r, Re) from the laboratory data.

</DOC>
<DOC>
<DOCNO> 120087 </DOCNO>
A survey of hard spectrum ROSAT sources 1: X-ray source catalogue


  We present a catalogue of 147 serendipitous X-ray sources selected to have
hard spectra (alpha < 0.5) from a survey of 188 ROSAT fields. Such sources must
be the dominant contributors to the X-ray background at faint fluxes. We have
used Monte Carlo simulations to verify that our technique is very efficient at
selecting hard sources: the survey has > 10 times as much effective area to
hard sources as it has to soft sources above a 0.5 - 2 keV flux level of 10^-14
erg/cm^2/s. The distribution of best fit spectral slopes of the hard sources
suggests that a typical ROSAT hard source in our survey has a spectral slope
alpha ~0. The hard sources have a steep number flux relation (dN/dS propto
S^-gamma with a best fit value of gamma = 2.72 +- 0.12) and make up about 15%
of all 0.5 - 2 keV sources with S > 10^-14 erg/cm^2/s. If their N(S) continues
to fainter fluxes, the hard sources will comprise ~ 40% of sources with 5
10^-15 < S < 10^-14. The population of hard sources can therefore account for
the harder average spectra of ROSAT sources with S < 10^-14. They probably make
a strong contribution to the X-ray background at faint fluxes and could be the
solution to the X-ray background spectral paradox.

</DOC>
<DOC>
<DOCNO> 9111 </DOCNO>
First-order quantum phase transition in the orthogonal-dimer spin chain


  We investigate the low-energy properties of the orthogonal-dimer spin chain
characterized by a frustrated dimer-plaquette structure. When the competing
antiferromagnetic couplings are varied, the first-order quantum phase
transition occurs between the dimer and the plaquette phases, which is
accompanied by nontrivial features due to frustration: besides the
discontinuity in the lowest excitation gap at the transition point, a sharp
level-crossing occurs for the spectrum in the plaquette phase. We further
reveal that the plateau in the magnetization curve at 1/4 of the full moment
dramatically changes its character in the vicinity of the critical point. It is
argued that the first-order phase transition in this system captures some
essential properties found in the two-dimensional orthogonal-dimer model
proposed for $\rm SrCu_2(BO_3)_2$.

</DOC>
<DOC>
<DOCNO> 10153 </DOCNO>
Medium/high field magnetoconductance in chaotic quantum dots


  The magnetoconductance G in chaotic quantum dots at medium/high magnetic
fluxes Phi is calculated by means of a tight binding Hamiltonian on a square
lattice. Chaotic dots are simulated by introducing diagonal disorder on surface
sites of L x L clusters. It is shown that when the ratio W/L is sufficiently
large, W being the leads width, G increases steadily showing a maximum at a
flux Phi_max ~ W. Bulk disordered ballistic cavities (with an amount of
impurities proportional to L) does not show this effect. On the other hand, for
magnetic fluxes larger than that for which the cyclotron radius is of the order
of L/2, the average magnetoconductance inceases almost linearly with the flux
with a slope proportional to W^2, shows a maximum and then decreases stepwise.
These results closely follow a theory proposed by Beenakker and van Houten to
explain the magnetoconductance of two point contacts in series.

</DOC>
<DOC>
<DOCNO> 9244 </DOCNO>
Collective Multi-Vortex States in Periodic Arrays of Traps


  We examine the vortex states in a 2D superconductor interacting with a square
array of pinning sites. As a function of pinning size or strength we find a
series of novel phases including multi-vortex and composite superlattice states
such as aligned dimer and trimer configurations at individual pinning sites.
Interactions of the vortices give rise to an orientational ordering of the
internal vortex structures in each pinning site. We also show that these vortex
states can give rise to a multi-stage melting behavior.

</DOC>
<DOC>
<DOCNO> 122913 </DOCNO>
Formation of the Planetary Sequence in a Highly Flattened Disk of


  The kinetic theory is used to study the evolution of the self-gravitating
disk of planetesimals. The effects of frequent collisions between planetesimals
are taken into account by using a Krook integral in the Boltzmann kinetic
equation. It is shown that as a result of an aperiodic collision-dissipative
instability of small gravity disturbances the disk is subdivided into numerous
dense fragments. These can eventually condense into the planetary sequence.

</DOC>
<DOC>
<DOCNO> 99443 </DOCNO>
The exterior algebra and `Spin' of an orthogonal g-module


  A well-known result of Kostant gives a description of the G-module structure
for the exterior algebra of Lie algebra $\frak g$. We give a generalization of
this result for the isotropy representations of symmetric spaces. If $\frak
g={\frak g}_0+{\frak g_1}$ is a Z_2-grading of a simple Lie algebra, we
explicitly describe a ${\frak g}_0$-module $Spin_0({\frak g}_1)$ such that the
exterior algebra of ${\frak g}_1$ is the tensor square of this module times
some power of 2. Although $Spin_0({\frak g}_1)$ is usually reducible, we show
that a Casimir element for ${\frak g}_0$ always acts scalarly on it.
  We also a give classification of all orthogonal representations of simple
algebraic groups having an exterior algebra of skew-invariants.

</DOC>
<DOC>
<DOCNO> 101886 </DOCNO>
Isometries of elliptic 3-manifolds


  The closed 3-manifolds of constant positive curvature were classified long
ago by Seifert and Threlfall. Using well-known information about the orthogonal
group O(4), we calculate their full isometry groups Isom(M), determine which
elliptic 3-manifolds admit Seifert fiberings that are invariant under all
isometries, and verify that the inclusion of Isom(M) to Diff(M) is a bijection
on path components.

</DOC>
<DOC>
<DOCNO> 12347 </DOCNO>
Exact solution for the Bariev model with boundary fields


  The Bariev model with open boundary conditions is introduced and analysed in
detail in the framework of the Quantum Inverse Scattering Method. Two classes
of independent boundary reflecting $K$-matrices leading to four different types
of boundary fields are obtained by solving the reflection equations. The models
are exactly solved by means of the algebraic nested Bethe ansatz method and the
four sets of Bethe ansatz equations as well as their corresponding energy
expressions are derived.

</DOC>
<DOC>
<DOCNO> 101006 </DOCNO>
Twist maps for non-standard quantum algebras and discrete Schrodinger


  The minimal twist map introduced by B. Abdesselam, A. Chakrabarti, R.
Chakrabarti and J. Segar (Mod. Phys. Lett. A 14 (1999) 765) for the
non-standard (Jordanian) quantum sl(2,R) algebra is used to construct the twist
maps for two different non-standard quantum deformations of the (1+1)
Schrodinger algebra. Such deformations are, respectively, the symmetry algebras
of a space and a time uniform lattice discretization of the (1+1) free
Schrodinger equation. It is shown that the corresponding twist maps connect the
usual Lie symmetry approach to these discrete equations with non-standard
quantum deformations. This relationship leads to a clear interpretation of the
deformation parameter as the step of the uniform (space or time) lattice.

</DOC>
<DOC>
<DOCNO> 84246 </DOCNO>
Exact plane gravitational waves and electromagnetic fields


  The behaviour of a "test" electromagnetic field in the background of an exact
gravitational plane wave is investigated in the framework of Einstein's general
relativity. We have expressed the general solution to the de Rham equations as
a Fourier-like integral. In the general case we have reduced the problem to a
set of ordinary differential equations and have explicitly written the solution
in the case of linear polarization of the gravitational wave. We have expressed
our results by means of Fermi Normal Coordinates (FNC), which define the proper
reference frame of the laboratory. Moreover we have provided some "gedanken
experiments", showing that an external gravitational wave induces measurable
effects of non tidal nature via electromagnetic interaction. Consequently it is
not possible to eliminate gravitational effects on electromagnetic field, even
in an arbitrarily small spatial region around an observer freely falling in the
field of a gravitational wave. This is opposite to the case of mechanical
interaction involving measurements of geodesic deviation effects. This
behaviour is not in contrast with the principle of equivalence, which applies
to arbitrarily small region of both space and time.

</DOC>
<DOC>
<DOCNO> 116755 </DOCNO>
New Design Study and Related Experimental Program for the LCLS RF


  We report the results of a recent beam dynamics study, motivated by the need
to redesign the LCLS photoinjector, that lead to the discovery of a new
effective working point for a split RF photoinjector. We consider the emittance
compensation regime of a space charge beam: by increasing the solenoid
strength, the emittance evolution shows a double minimum behavior in the
drifting region. If the booster is located where the relative emittance maximum
and the envelope waist occur, the second emittance minimum can be shifted to
the booster exit and frozen at a very low level (0.3 mm-mrad for a 1 nC flat
top bunch), to the extent that the invariant envelope matching conditions are
satisfied. Standing Wave Structures or alternatively Traveling Wave Structures
embedded in a Long Solenoid are both candidates as booster linac. A careful
measurement of the emittance evolution as a function of position in the
drifting region is necessary to verify the computation and to determine
experimentally the proper position of the booster cavities. The new design
study and supporting experimental program under way at the SLAC Gun Test
Facility are discussed.

</DOC>
<DOC>
<DOCNO> 152096 </DOCNO>
Solving N=3 super-Yang-Mills equations in harmonic superspace


  We analyze the superfield constraints of the D=4, N=3 SYM-theory using
light-cone gauge conditions. The SU(3)/U(1)xU(1) harmonic variables are
interpreted as auxiliary spectral parameters, and the transform to the
harmonic-superspace representation is considered. Our nilpotent gauge for the
basic harmonic superfield simplifies the SYM-equations of motion. A partial
Grassmann decomposition of these equations yields the solvable linear system of
iterative equations.

</DOC>
<DOC>
<DOCNO> 102650 </DOCNO>
Hypersurfaces and generalized deformations


  This paper has been withdrawn by the author while under revision.

</DOC>
<DOC>
<DOCNO> 150930 </DOCNO>
Single-scale diagrams and multiple binomial sums


  The $\epsilon$-expansion of several two-loop self-energy diagrams with
different thresholds and one mass are calculated. On-shell results are reduced
to multiple binomial sums which values are presented in analytical form.

</DOC>
<DOC>
<DOCNO> 8242 </DOCNO>
Unusually High Thermal Conductivity of Carbon Nanotubes


  Combining equilibrium and non-equilibrium molecular dynamics simulations with
accurate carbon potentials, we determine the thermal conductivity $\lambda$ of
carbon nanotubes and its dependence on temperature. Our results suggest an
unusually high value ${\lambda}{\approx}6,600$~W/m$\cdot$K for an isolated
(10,10) nanotube at room temperature, comparable to the thermal conductivity of
a hypothetical isolated graphene monolayer or diamond. Our results suggest that
these high values of $\lambda$ are associated with the large phonon mean free
paths in these systems; substantially lower values are predicted and observed
for the basal plane of bulk graphite.

</DOC>
<DOC>
<DOCNO> 117068 </DOCNO>
The influence of a metallic sheet on an evanescent mode atomic mirror


  A theory of evanescent mode atomic mirrors utilising a metallic sheet on a
dielectric substrate is described. The emphasis here is on the role of the
metallic sheet and on the evaluation of atomic trajectories using the field-
dipole orientation picture. At low intensity, the atomic reflection process is
controlled by two separate mechanisms both of which are modified by the
presence of the metallic sheet and influenced by the use of the field-dipole
orientation picture. The first mechanism involves the spontaneous force which
accelerates the atom parallel to the sheet plane. The second mechanism involves
the combined dipole plus van der Waals force which acts to repel the atom from
the surface, decelerating its motion until it attains an instantaneous halt
before changing direction away from the surface at an appr opriate turning
point in the trajectory. Various quantitative features arising from varying the
controllable parameters of the system, including screening effects as well as
desirable enhancement effects, are pointed out and discussed.

</DOC>
<DOC>
<DOCNO> 13412 </DOCNO>
Surface critical behavior of random systems at the ordinary transition


  We calculate the surface critical exponents of the ordinary transition
occuring in semi-infinite, quenched dilute Ising-like systems. This is done by
applying the field theoretic approach directly in d=3 dimensions up to the
two-loop approximation, as well as in $d=4-\epsilon$ dimensions. At
$d=4-\epsilon$ we extend, up to the next-to-leading order, the previous
first-order results of the $\sqrt{\epsilon}$ expansion by Ohno and Okabe
[Phys.Rev.B 46, 5917 (1992)]. In both cases the numerical estimates for surface
exponents are computed using Pade approximants extrapolating the perturbation
theory expansions. The obtained results indicate that the critical behavior of
semi-infinite systems with quenched bulk disorder is characterized by the new
set of surface critical exponents.

</DOC>
<DOC>
<DOCNO> 10366 </DOCNO>
Pattern formation and selection in quasi-static fracture


  Fracture in quasi-statically driven systems is studied by means of a discrete
spring-block model. Developed from close comparison with desiccation
experiments, it describes crack formation induced by friction on a substrate.
The model produces cellular, hierarchical patterns of cracks, characterized by
a mean fragment size linear in the layer thickness, in agreement with
experiments. The selection of a stationary fragment size is explained by
exploiting the correlations prior to cracking. A scaling behavior associated
with the thickness and substrate coupling, derived and confirmed by
simulations, suggests why patterns have similar morphology despite their
disparity in scales.

</DOC>
<DOC>
<DOCNO> 100913 </DOCNO>
Quantum b-functions of prehomogeneous vector spaces of commutative


  We show that there exists a natural q-analogue of the b-function for the
prehomogeneous vector space of commutative parabolic type, and calculate them
explicitly in each case. Our method of calculating the b-functions seems to be
new even for the original case q=1.

</DOC>
<DOC>
<DOCNO> 7959 </DOCNO>
Bose-Einstein Condensation in Classical Systems


  It is shown, that Bose-Einstein statistical distributions can occur not only
in quantum system, but in classical systems as well. The coherent dynamics of
the system, or equivalently autocatalytic dynamics in momentum space of the
system is the main reason for the Bose-Einstein condensation. A coherence is
possible in both quantum and classical systems, and in both cases can lead to
Bose-Einstein statistical distribution.

</DOC>
<DOC>
<DOCNO> 101146 </DOCNO>
Theory of Finite Pseudoalgebras


  Conformal algebras, recently introduced by Kac, encode an axiomatic
description of the singular part of the operator product expansion in conformal
field theory. The objective of this paper is to develop the theory of
``multi-dimensional'' analogues of conformal algebras. They are defined as Lie
algebras in a certain ``pseudotensor'' category instead of the category of
vector spaces. A pseudotensor category (as introduced by Lambek, and by
Beilinson and Drinfeld) is a category equipped with ``polylinear maps'' and a
way to compose them. This allows for the definition of Lie algebras,
representations, cohomology, etc. An instance of such a category can be
constructed starting from any cocommutative (or more generally,
quasitriangular) Hopf algebra $H$. The Lie algebras in this category are called
Lie $H$-pseudoalgebras.
  The main result of this paper is the classification of all simple and all
semisimple Lie $H$-pseudoalgebras which are finitely generated as $H$-modules.
We also start developing the representation theory of Lie pseudoalgebras; in
particular, we prove analogues of the Lie, Engel, and Cartan-Jacobson Theorems.
We show that the cohomology theory of Lie pseudoalgebras describes extensions
and deformations and is closely related to Gelfand-Fuchs cohomology. Lie
pseudoalgebras are closely related to solutions of the classical Yang-Baxter
equation, to differential Lie algebras (introduced by Ritt), and to Hamiltonian
formalism in the theory of nonlinear evolution equations. As an application of
our results, we derive a classification of simple and semisimple linear Poisson
brackets in any finite number of indeterminates.

</DOC>
<DOC>
<DOCNO> 99912 </DOCNO>
Multivariate hypergeometric functions as tau functions of Toda lattice


  We present the q-deformed multivariate hypergeometric functions related to
Schur polynomials as tau-functions of the KP and of the two-dimensional Toda
lattice hierarchies. The variables of the hypergeometric functions are the
higher times of those hierarchies. The discrete Toda lattice variable shifts
parameters of hypergeometric functions. The role of additional symmetries in
generating hypergeometric tau-functions is explained.

</DOC>
<DOC>
<DOCNO> 120848 </DOCNO>
The Age of the Galaxy from Thorium Cosmochronometry


  The long-lived radioactive element thorium can potentially provide a simple
and direct clock to determine the age of our Galaxy. Spectroscopic
investigations of thorium in metal-poor stars have yielded some promising
initial results. We discuss the major observational and theoretical limitations
in thorium cosmochronometry, and point out the ways in which the implied
Galactic ages from thorium abundances can be made more accurate.

</DOC>
<DOC>
<DOCNO> 121408 </DOCNO>
Reconstruction of radial temperature profiles of galaxy clusters


  In this Letter we present the radial temperature profiles of three X-ray
clusters (A119, A2255 and A2256) reconstructed from a combination of the X-ray
surface brightness measurements and the universal density profile as the
underlying dark matter distribution. Our algorithm is based on the hydrostatic
equilibrium for intracluster gas and the universality of the total baryon
fraction within the virial radius. The scaled temperature profiles of these
three clusters appear to be remarkably similar in shape, reflecting the
underlying structural regularity, although they are inconsistent with either
isothermality or a significant decline with increasing radius. Nevertheless, we
find a good agreement between our derived temperature profiles and the recent
analysis of 11 clusters observed with BeppoSAX (Irwin & Bregman 2000), which
provides a useful clue to resolving the temperature profile discrepancy raised
recently in literature. A comparison of our derived temperature profiles with
future spatially-resolved spectral measurements may constitute a critical test
for the standard model of structure formation and the conventional scenario for
dynamical properties of clusters.

</DOC>
<DOC>
<DOCNO> 117519 </DOCNO>
APM 08279+5255: Keck Near- and Mid-IR High-Resolution Imaging


  We present Keck high-resolution near-IR (2.2 microns; FWHM~0.15") and mid-IR
(12.5 microns; FWHM~0.4") images of APM08279+5255, a z=3.91 IR-luminous BALQSO
with a prodigious apparent bolometric luminosity of 5x10^{15} Lsun, the largest
known in the universe. The K-band image shows that this system consists of
three components, all of which are likely to be the gravitationally lensed
images of the same background object, and the 12.5 micron image shows a
morphology consistent with such an image configuration. Our lens model suggests
that the magnification factor is ~100 from the restframe UV to mid-IR, where
most of the luminosity is released. The intrinsic bolometric luminosity and IR
luminosity of APM08279+5255 are estimated to be 5x10^{13} Lsun and 1x10^{13}
Lsun, respectively. This indicates that APM 08279+5255 is intriniscally
luminous, but it is not the most luminous object known. As for its dust
contents, little can be determined with the currently available data due to the
uncertainties associated with the dust emissivity and the possible effects of
differential magnification. We also suggest that the lensing galaxy is likely
to be a massive galaxy at z~3.

</DOC>
<DOC>
<DOCNO> 67820 </DOCNO>
CP Violating Phases and the Dark Matter Problem


  New CP violating phases in the MSSM can affect both the abundance and
detection of neutralino dark matter. We discuss the effect of including
cosmological constraints in the limits on new sources of CP violation in the
MSSM and the effects of new CP violating parameters on dark matter densities
and detection.

</DOC>
<DOC>
<DOCNO> 67794 </DOCNO>
Large-N Gauge Theories


  Four pedagogical Lectures at the NATO-ASI on "Quantum Geometry" in Akureyri,
Iceland, August 1999. Contents: 1. O(N) Vector Models, 2. Large-N QCD, 3. QCD
in Loop Space, 4. Large-N Reduction

</DOC>
<DOC>
<DOCNO> 121104 </DOCNO>
Low-luminosity AGN and Normal Galaxies


  Low-luminosity AGN (with X-ray luminosity < 1e42 ergs/s) far outnumber
ordinary AGN, and are therefore perhaps more relevant to our understanding of
AGN phenomena and the relationship between AGN and host galaxies. Many normal
galaxies harbor LINER and starburst nuclei, which, together with LLAGN, are a
class of ``low-activity'' galaxies that have a number of surprisingly similar
X-ray characteristics, despite their heterogenous optical classification. This
strongly supports the hypothesis of an AGN-starburst connection. Further, X-ray
observations of normal galaxies without starburst or AGN-like activity in their
nuclei offer opportunities to study populations of X-ray binaries, HII regions,
and warm or hot ISM under different conditions than is often the case in the
Milky Way. The results of recent X-ray observations of these types of galaxies
are reviewed, and what we hope to learn about both nearby and high redshift
galaxies of each type from observations with forthcoming and planned satellites
is discussed.

</DOC>
<DOC>
<DOCNO> 10560 </DOCNO>
Scaling of avalanche queues in directed dissipative sandpiles


  We simulate queues of activity in a directed sandpile automaton in 1+1
dimensions by adding grains at the top row with driving rate $0 < r \leq 1$.
The duration of elementary avalanches is exactly described by the distribution
$P_1(t) \sim t^{-3/2}\exp{(-1/L_c)}$, limited either by the system size or by
dissipation at defects $L_c= \min (L,\xi)$. Recognizing the probability $P_1$
as a distribution of service time of jobs arriving at a server with frequency
$r$, the model represents a new example of the $<E,1,GI/\infty/1> $ server
queue in the queue theory. We study numerically and analytically the tail
behavior of the distributions of busy periods and energy dissipated in the
queue and the probability of an infinite queue as a function of driving rate.

</DOC>
<DOC>
<DOCNO> 69400 </DOCNO>
Optimisation of the exact renormalisation group


  A simple criterion to optimise coarse-grainings for exact renormalisation
group equations is given. It is aimed at improving the convergence of
approximate solutions of flow equations. The optimisation criterion is generic,
as it refers only to the coarse-grained propagator at vanishing field. In
physical terms, it is understood as an optimisation condition for amplitude
expansions. Alternatively, it can be interpreted as the requirement to move
poles of threshold functions away from the physical region. The link to
expansions in field amplitudes is discussed as well. Optimal parameters are
given explicitly for a variety of different coarse-grainings. As a by-product
it is found that the sharp cut-off regulator does not belong to the class of
such optimal coarse-grainings, which explains the poor convergence of amplitude
expansions based on it.

</DOC>
<DOC>
<DOCNO> 152225 </DOCNO>
Damped harmonic oscillators in the holomorphic representation


  Quantum dynamical semigroups are applied to the study of the time evolution
of harmonic oscillators, both bosonic and fermionic. Explicit expressions for
the density matrices describing the states of these systems are derived using
the holomorphic representation. Bosonic and fermionic degrees of freedom are
then put together to form a supersymmetric oscillator; the conditions that
assure supersymmetry invariance of the corresponding dynamical equations are
explicitly derived.

</DOC>
<DOC>
<DOCNO> 8263 </DOCNO>
1D lattice dynamics of the diffusion limited reaction A+A->A+S:


  We use a boolean cellular automaton model to describe the diffusion limited
dynamics of the irreversible reaction A+A->A+S on a 1D lattice. We derive a set
of equations for the dynamics of the empty interval probabilities from which
explicit expressions for the particle concentration and the two-point
correlation can be obtained. It is shown that the long time dynamics is in
agreement with the off-lattice solution. The early time behavior, however,
predicts a slower decay of the concentration.

</DOC>
<DOC>
<DOCNO> 123083 </DOCNO>
Canonical elements for collision orbits


  I derive a set of canonical elements that are useful for collision orbits
(perihelion distance approaching zero at fixed semimajor axis). The coordinates
are the mean anomaly and the two spherical polar angles at aphelion.

</DOC>
<DOC>
<DOCNO> 117404 </DOCNO>
X-ray and optical observations of three clusters of galaxies: Abell 901,


  We analyse three clusters of galaxies, Abell 901 (z=0.17), Abell 1437
(z=0.13) and Abell 3570 (z=0.037). They have low to intermediate X-ray fluxes
and an irregular morphology in the ROSAT All-Sky Survey (RASS). These clusters
are chosen to test the abilities and limitations of the RASS in terms of
cluster fluxes and cluster morphologies. Therefore some ``worst'' cases are
used here. X-ray observations with the ROSAT/HRI and optical spectroscopic
observations are carried out. The ROSAT/HRI observations, which have a much
better spatial resolution than the RASS, reveal in two of the three cases a
significantly different morphology than seen in the RASS. The reasons are point
sources which could not be resolved in the RASS and were therefore confused
with the cluster emission. For A3570 we could confirm the relaxed state of the
cluster by the optical determination of a small velocity dispersion. In the
cluster with the lowest flux (Abell 901) the countrate measurement is strongly
affected by point sources, in the two other cases the countrate measurements of
the RASS are reliable, i.e. they are reproduced by the ROSAT/HRI measurement.
We conclude that for clusters with a flux of a few times 10^{-12} erg/cm^2/s or
smaller, which show at the same time a non-relaxed morphology, the flux
measurement of the RASS can be seriously affected by fore- or background
sources. We point out that an all-sky survey of a second ABRIXAS mission would
provide a much clearer source distinction for low-flux clusters and thus a much
improved countrate determination.

</DOC>
<DOC>
<DOCNO> 121160 </DOCNO>
Massive star populations and the IMF in metal-rich starbursts


  We present new spectroscopic observations of Mkn 309, a starburst galaxy with
one of the largest WR populations known. A highly super solar metallicity is
derived. Using additional objects we analyse a sample of five metal-rich WR
galaxies with the main goal of constraining the basic properties of the massive
star populations (IMF slope, M_up) and the star formation history (age, burst
duration) of these objects by quantitative comparisons with evolutionary
synthesis models. The following main results are obtained: 1) The observations
are well explained by extended bursts of star formation or a superposition of
several bursts. Ages and burst durations are estimated. This naturally explains
both the observed WR populations (including WN and WC stars) and the presence
of red supergiants. 2) The fitted SEDs indicate that the stellar light suffers
from a smaller extinction than that of the gas, confirming independent earlier
findings. 3) All the considered observational constraints are compatible with a
Salpeter IMF extending to masses >~ 40 Msun. Adopting a conservative approach
we derive a LOWER LIMIT of Mup >~ 30 Msun for the Salpeter IMF. From more
realistic assumptions on the metallicity and SF history we favour a lower limit
Mup >~ 30-40 Msun, which is also in agreement with Hbeta equivalent width
measurements of metal-rich HII regions in spiral galaxies indicating an upper
mass cut-off of at least ~ 35 - 50 Msun. Steep IMF slopes (alpha >~ 3.3) are
very unlikely. (abridged/modified abstract)

</DOC>
<DOC>
<DOCNO> 69614 </DOCNO>
Extraction of skewed parton distributions


  Skewed parton distributions contain new non-perturbative information about
hadronic states. Thus, their extraction from experimental data is an important
goal. Properties and models for skewed parton distributions as well as their
extraction, based on perturbative leading-order results, are shortly reviewed.

</DOC>
<DOC>
<DOCNO> 84333 </DOCNO>
On the selection of triads in the teleparallel geometry and Bondi's


  A consistent Hamiltonian formulation of the teleparallel equivalent of
general relativity (TEGR) requires the theory to be invariant under the global
SO(3) symmetry group, which acts on orthonormal triads in three-dimensional
spacelike hypersurfaces. In the TEGR it is possible to make definite statements
about the energy of the gravitational field. In this geometrical framework two
sets of triads related by a local SO(3) transformation yield different
descriptions of the gravitational energy. Here we consider the problem of
assigning a unique set of triads to the metric tensor restricted to the
three-dimensional hypersurface. The analysis is carried out in the context of
Bondi's radiating metric. A simple and original expression for Bondi's news
function is obtained, which allows us to carry out numerical calculations and
verify that a triad with a specific asymptotic behaviour yields the minimum
gravitational energy for a fixed space volume containing the radiating source.
This result supports the conjecture that the requirement of a minimum
gravitational energy for a given space volume singles out uniquely the correct
set of orthonormal triads.

</DOC>
<DOC>
<DOCNO> 119131 </DOCNO>
A deep X-ray observation of NGC 4258 and its surrounding field


  We present a deep X-ray observation of the low-luminosity active galactic
nucleus in NGC4258 (M106) using ASCA. The soft X-ray spectrum <2keV is
dominated by thermal emission from optically-thin plasma with kT~0.5keV. The
hard X-ray emission is clearly due to a power-law component with photon index
Gamma=1.8 absorbed by a column density of N_H=8x10^22/cm^2. The power-law is
readily identified with primary X-ray emission from the AGN central engine. We
also clearly detect a narrow iron K-alpha emission line at 6.4keV. No broad
component is detected. We suggest that the bulk of this narrow line comes from
the accretion disk and, furthermore, that the power-law X-ray source which
excites this line emission (which is typically identified with a disk corona)
must be at least 100GM/c^2 in extent. This is in stark contrast to many
higher-luminosity Seyfert galaxies which display a broad iron line indicating a
small 10 GM/c^2 X-ray emitting region. It must be stressed that this study
constrains the size of the X-ray emitting corona rather than the
presence/absence of a radiatively efficient accretion disk in the innermost
regions. If, instead, a substantial fraction of the observed narrow line
originates from material not associated with the accretion disk, limits can be
placed on the parameter space of possible allowed relativistically broad iron
lines. By comparing our data with previous ASCA observations, we find marginal
evidence for a change in absorbing column density through to the central
engine, and good evidence for a change in the AGN flux.

</DOC>
<DOC>
<DOCNO> 119655 </DOCNO>
Constraints on diffuse neutrino background from primordial black holes


  We calculated the energy spectra and the fluxes of electron neutrino emitted
in the process of evaporation of primordial black holes (PBHs) in the early
universe. It was assumed that PBHs are formed by a blue power-law spectrum of
primordial density fluctuations. We obtained the bounds on the spectral index
of density fluctuations assuming validity of the standard picture of
gravitational collapse and using the available data of several experiments with
atmospheric and solar neutrinos. The comparison of our results with the
previous constraints (which had been obtained using diffuse photon background
data) shows that such bounds are quite sensitive to an assumed form of the
initial PBH mass function.

</DOC>
<DOC>
<DOCNO> 102629 </DOCNO>
Inverse Grobner Basis Problem in Codimension Two


  Generic linkage is used to compute a prime ideal such that the radical of the
initial ideal of the prime ideal is equal to the radical of a given codimension
two monomial ideal that has a Cohen-Macaulay quotient ring.

</DOC>
<DOC>
<DOCNO> 10962 </DOCNO>
Electronic structure and magnetism in disordered bcc Fe alloys


  We here study electronic structure and magnetic properties of bcc
Co$_{x}$Fe$_{1-x}$, Cr$_{x}$Fe$_{1-x}$ and Mn$_{x}$Fe$_{1-x}$ in their
ferromagnetic phases using Augmented Space Recursion technique coupled with
tight-binding linearized muffin tin orbital (TB-LMTO) method. We make a
systematic study of magnetic properties like magnetic moment and Curie
temperature and try to draw some conclusions on their variation across the row
of 3-{\it d} transition metal series in periodic table using arguments based on
effects like charge transfer, exchange splitting and hybridization.

</DOC>
<DOC>
<DOCNO> 151366 </DOCNO>
Quantum structure of T-dualized models with symmetry breaking


  We study the principal sigma-models defined on any group manifold GL x GR/GD
with breaking of GR, and their T-dual transforms. For abritary breaking we can
express the torsion and Ricci tensor of the dual model in terms of the frame
geometry of the initial principal model. Using these results, we give necessary
and sufficient conditions for the dual model to be torsionless and prove that
the one-loop renormalizability of a given principal model is inherited by its
dual partner, who shares the same beta-functions. These results are shown to
hold also if the principal model is endowed with torsion. As an application we
compute the beta-functions for the full Bianchi family and show that for some
choices of the breaking parameters the dilaton anomaly is absent: for these
choices the dual torsion vanishes. For the dualized Bianchi V model (which is
torsionless for any breaking), we take advantage of its simpler structure, to
study its two-loops renormalizability.

</DOC>
<DOC>
<DOCNO> 71277 </DOCNO>
A sum rule from the shape function


  We present a sum rule relating the electron energy spectrum and the hadron
mass distribution in semileptonic b -> u decays close to threshold. The
relation found is free from non-perturbative effects and the theoretical error
is expected to be O(5%). An experimental confirmation of this prediction can
provide a check of the basic assumptions at the root of the theory of the shape
function.

</DOC>
<DOC>
<DOCNO> 40507 </DOCNO>
Neutrino Physics: An Experimental Overview


  The field of neutrino physics is currently very exciting, with several recent
results pointing to new physics. I will give an overview of the current
experimental situation, focusing primarily on neutrino oscillation results. The
data are not entirely consistent however, and puzzles remain. I will then
review the new experiments which are poised to solve the outstanding puzzles.

</DOC>
<DOC>
<DOCNO> 84178 </DOCNO>
Probable Values of the Cosmological Constant in a Holographic Theory


  We point out that for a large class of universes, holography implies that the
most probable value of the cosmological constant is zero. In four spacetime
dimensions, the probability distribution takes the Baum-Hawking form,
$dP\sim\exp(cM_p^2/\Lambda)d\Lambda$.

</DOC>
<DOC>
<DOCNO> 85508 </DOCNO>
Brane Cosmology in the Background of D-Brane with NS B Field


  We study the cosmological evolution of the four-dimensional universe on the
probe D3-brane in geodesic motion in the curved background of the source
Dp-brane with non-zero NS B field. The Friedman equations describing the
expansion of the brane universe are obtained and analyzed for various limits.
We elaborate on corrections to the cosmological evolution due to nonzero NS B
field.

</DOC>
<DOC>
<DOCNO> 7790 </DOCNO>
Friedel Oscillations and Charge-density Waves Pinning in


  We present an x-ray diffraction study of the Vanadium-doped blue bronze
K0.3(Mo0.972V0.028)O3. At low temperature, we have observed both an intensity
asymmetry of the +-2kF satellite reflections relative to the pure compound, and
a profile asymmetry of each satellite reflections. We show that the profile
asymmetry is due to Friedel oscillation around the V substituant and that the
intensity asymmetry is related to the charge density wave (CDW) pinning. These
two effects, intensity and profile asymmetries, gives for the first time access
to the local properties of CDW in disordered systems, including the pinning and
even the phase shift of FOs.

</DOC>
<DOC>
<DOCNO> 116452 </DOCNO>
Rapid acceleration of electrons in the magnetosphere by fast-mode MHD


  During major megnetic storms, enhanced flux of relativistic electrons in the
inner magnetosphere have been observed to correleated with ULF waves. The
enhancements can take place over a period of several hours. In order to account
for such a rapid generation of relativistic electrons, we examine the mechanism
of transit-time acceleration of electrons by low-frequency fast-mode MHD waves,
here the assumed form of ULF waves. Calcaulations of the acceleration
timescales in the model show that fast-mode waves in the Pc4 to Pc5 frequency
range, with typically observed wave amplitudes 10--20 nT, can accelerate the
seed electrons to energies of order MeV in a period of a few hours.

</DOC>
<DOC>
<DOCNO> 40233 </DOCNO>
$B\to \phi K$ and $B\to \phi X_s$ in the Heavy Quark Limit


  We study $B\to \phi K$ and $B\to \phi X_s$ decays in the heavy quark limit
using perturbative QCD. The next leading order corrections introduce
substantial modifications to the naive factorization results (more than 50%).
The branching ratio $Br(B\to \phi K)$ is predicted to be in the range $(F^{B\to
K}_1(m^2_\phi)/0.33)^2(3.5\sim 4.2) \times 10^{-6}$ which is within the one
$\sigma$ allowed region from the central value of $6.2\times 10^{-6}$ measured
by CLEO, but outside the one $\sigma$ allowed region from the central value of
$17.2\times 10^{-6}$ measured by BELLE for reasonable $F_1^{B\to K}$. For the
semi-inclusive decay $B\to \phi X_s$ we also include initial bound state effect
in the heavy quark limit which decreases the branching ratio by about 10%.
$Br(B\to \phi X_s)$ is predicted to be in the range $(5.1\sim 6.3)\times
10^{-5}$.

</DOC>
<DOC>
<DOCNO> 178582 </DOCNO>
Band Crossing and Signature Splitting in Odd Mass fp Shell Nuclei


  Structure of two sets of mirror nuclei: 47V - 47Cr and 49Cr - 49Mn, as well
as 49V and 51Mn, is studied using the projected shell model. Their yrast
spectra are described as an interplay between the angular momentum projected
states around the Fermi level which carry different intrinsic K-quantum
numbers. The deviations from a regular rotational sequence are attributed to
band crossing and signature splitting, which are usually discussed in heavy
nuclear systems. Our results agree reasonably with experimental data, and are
comparable with those from the full $pf$ shell model calculations.

</DOC>
<DOC>
<DOCNO> 68310 </DOCNO>
Sources for Electroweak Baryogenesis


  I review a computation of the baryon asymmetry arising from a first order
electroweak phase transition in the Minimal Supersymmetric Standard model by
classical force mechanism (CFM). I focus on CP violation provided by the
charginos and show that it is the usually neglected sum of the two Higgsino
fields, H_1+H_2, which gives a larger contribution to the baryon asymmetry than
does the combination H_1-H_2. In fact, the latter contribution is exactly zero
in CFM, because it is associated with a phase transformation of the fields.
Baryogenesis is found to be most effective in MSSM CFM when only $\tilde t_R$
is light, which lends independent support for the "light stop scenario", and it
remains viable for CP-violating phases as small as \delta_\mu \sim {\it few}
\times 10^{-3}.

</DOC>
<DOC>
<DOCNO> 71423 </DOCNO>
Chiral Limit Prediction for epsilon'/epsilon at NLO in 1/N_c


  We report on a calculation of $\epsilon_K'/\epsilon_K$ at next-to-leading in
the $1/N_c$ expansion and to lowest order in Chiral Perturbation Theory. We
discuss the short-distance matching, the scale and scheme dependence as well as
the long-distance short-distance matching. We include the two known chiral
corrections to our result and discuss further order $p^4$ corrections to it.

</DOC>
<DOC>
<DOCNO> 84800 </DOCNO>
Cosmology with Curvature-Saturated Gravitational Lagrangian R/\sqrt{1 +


  We argue that the Lagrangian for gravity should remain bounded at large
curvature, and interpolate between the weak-field tested Einstein-Hilbert
Lagrangian L_EH = R /16 pi G and a pure cosmological constant for large R with
the curvature-saturated ansatz L_cs=L_EH/ \sqrt{1+l^4 R^2}, where l is a length
parameter expected to be a few orders of magnitude above the Planck length. The
curvature-dependent effective gravitational constant defined by dL/dR = 1/16 pi
G_eff is G_eff = G \sqrt{1+l^4 R^2}^{3}, and tends to infinity for large $R$,
in contrast to most other approaches where G_eff-> 0. The theory possesses
neither ghosts nor tachyons. In a curvature-saturated cosmology, the
coordinates with ds^2 = a^2 [da^2/B(a) - dx^2 - dy^2- dz^2] are most convenient
since the curvature scalar becomes a linear function of $B(a)$. Solutions with
a big-bang singularity have a much milder behavior of the curvature than in
Einstein's theory. In synchronized time, the metric is given by ds^2 = dt^2 -
t^{6/5(dx^2 + dy^2+ dz^2). On the technical side we show that two different
conformal transformations make L_cs asymptotically equivalent to the
Gurovich-ansatz L= | R |^{4/3} on the one hand, and to Einstein's theory with a
minimally coupled scalar field with self-interaction on the other.

</DOC>
<DOC>
<DOCNO> 84193 </DOCNO>
Can Quantum Cosmology Give Observational Consequences of Many-Worlds


  Although many people have thought that the difference between the Copenhagen
and many-worlds versions of quantum theory was merely metaphysical, quantum
cosmology may allow us to make a physical test to distinguish between them
empirically. The difference between the two versions shows up when the various
components of the wavefunction have different numbers of observers and
observations. In the Copenhagen version, a random observation is selected from
the sample within the component that is selected by wavefunction collapse, but
in the many-worlds version, a random observation is selected from those in all
components. Because of the difference in the samples, probable observations in
one version can be very improbable in the other version.

</DOC>
<DOC>
<DOCNO> 80684 </DOCNO>
The Berry Phase and Monopoles in Non-Abelian Gauge Theories


  We consider the quantum mechanical notion of the geometrical (Berry) phase in
SU(2) gauge theory, both in the continuum and on the lattice. It is shown that
in the coherent state basis eigenvalues of the Wilson loop operator naturally
decompose into the geometrical and dynamical phase factors. Moreover, for each
Wilson loop there is a unique choice of U(1) gauge rotations which do not
change the value of the Berry phase. Determining this U(1) locally in terms of
infinitesimal Wilson loops we define monopole-like defects and study their
properties in numerical simulations on the lattice. The construction is gauge
dependent, as is common for all known definitions of monopoles. We argue that
for physical applications the use of the Lorenz gauge is most appropriate. And,
indeed, the constructed monopoles have the correct continuum limit in this
gauge. Physical consequences are briefly discussed.

</DOC>
<DOC>
<DOCNO> 121927 </DOCNO>
Known and unknown SCUBA sources


  Summary and discussion of some projects to use SCUBA to target sources
selected at other wavebands, as well as to find new sub-mm galaxies in `blank
fields': FIRBACK galaxies; Lyman break galaxies and `the Blob'; HDF flanking
fields and the Groth Strip; survey of lensing cluster fields.

</DOC>
<DOC>
<DOCNO> 10795 </DOCNO>
Solving the phase problem in i(AlPdMn)


  We apply a new technique for ab initio phase determination [Acta Crystallogr.
Sect. A, A55, 48 (1999)] to solve for the average structure of the icosahedral
(i) phase of AlPdMn. After an introduction to the crystallographic phase
problem and a description of the method, we present a brief report of our
findings for the structure of i(AlPdMn). Despite the use of data from extremely
high quality samples, we find strong evidence of disorder in the structure,
lending support to the random tiling model of quasicrystal stabilization.

</DOC>
<DOC>
<DOCNO> 84086 </DOCNO>
Fermion Stars with an Extra Dimension


  Many efforts have been devoted to the studies of the phenomenology in
particle physics with extra dimensions. We propose the degenerate fermion star
in the five dimensions, and study what effects caused by the geometry of extra
dimensions should appear in its structure. We note that Kaluza-Klein excited
modes have effects for the larger scale of extra dimensions and examine the
conditions on which different layers should be caused in the inside of the
stars. We expound how the effects of the extra dimensions appears on physical
quantities.

</DOC>
<DOC>
<DOCNO> 84480 </DOCNO>
Non-Linear gravitational growth of large scale structures inside and


  We reconsider the problem of gravitational structure formation inside and
outside General Relativity (GR), both in the weakly and strongly non-linear
regime. We show how these regimes can be explored observationally through
clustering of high order cumulants and through the epoch of formation,
abundance and clustering of collapse structures, using Press-Schechter
formalism and its extensions. We address the question of how different are
these predictions when using a non-standard theory of Gravity. We study
examples of cosmologies that do not necessarily obey Einstein's field
equations: scalar-tensor theories (STT), such as Brans-Dicke (BD), parametrized
with $\omega$, a non-standard parametrisation of the Hubble law, $H^2=
a^{-3(1+\epsilon)}$, or a non-standard cosmic equation of state $p=\gamma\rho$,
where $\gamma$ can be chosen irrespective of the cosmological parameters
($\Omega_M$ and $\Omega_\Lambda$). We present some preliminary bounds on
$\gamma$, $\omega$ and $\epsilon$ from observations of the skewness and
kurtosis in the APM Galaxy Survey. This test is independent of the overall
normalization of rms fluctuations. We also show how abundances and formation
times change under these assumptions. Upcoming data on non-linear growth will
place strong constraints on such variations from the standard paradigm.

</DOC>
<DOC>
<DOCNO> 68242 </DOCNO>
The Standard Model instability and the scale of new physics


  We apply a general formalism for the improved effective potential with
several mass scales to compute the scale M of new physics which is needed to
stabilize the Standard Model potential in the presence of a light Higgs. We
find, by imposing perturbativity of the new physics, that M can be as large as
one order of magnitude higher than the instability scale of the Standard Model.
This implies that, with the present lower bounds on the Higgs mass, the new
physics could easily (but not necessarily) escape detection in the present and
future accelerators.

</DOC>
<DOC>
<DOCNO> 102754 </DOCNO>
Smooth Character Varieties for Torus Knot Groups


  Semisimple representations of the free product Z_p*Z_q determine
\theta-semistable representations of a specific quiver Q_pq. The dimension
vectors of \theta-stable representations of this quiver were classified by Le
Bruyn and Adriaenssens. In this paper we classify the moduli spaces
M_\alpha^ss(Q_pq,\theta) which are smooth projective varieties.

</DOC>
<DOC>
<DOCNO> 69598 </DOCNO>
Error propagation in QCD fits


  The parton momentum density distributions of the proton were obtained from a
NLO QCD analysis of HERA and fixed target structure function data. The
resulting parton distribution set includes the full information on errors and
correlations.

</DOC>
<DOC>
<DOCNO> 69747 </DOCNO>
Time Evolution of Decay Spectrum in K^0, K^0 bar -> pi^+ pi^- e^+ e^-


  We consider the decay K^0 (K^0 bar) -> pi^+ pi^- e^+ e^- of a neutral K meson
prepared in a state of strangeness +1 (-1). The time evolution of the state
produces remarkable time-dependent effects in the angular distribution of the
pi^+ pi^- e^+ e^- system. These effects are correlated with the time-dependence
of the photon polarization in the radiative decay K^0 (K^0 bar) -> pi^+ pi^-
gamma. We study, in particular, the CP-odd, T-odd term in the distribution d
Gamma / d phi of the angle between the pi^+ pi^- and the e^+ e^- planes. We
also give the spectrum in the case that the decaying meson is an incoherent
mixture of K^0 and K^0 bar, and discuss the case of K_S regeneration in a K_L
beam.

</DOC>
<DOC>
<DOCNO> 152343 </DOCNO>
Left-Right Symmetric Models in Noncommutative Geometries?


  Left-right symmetric models are analyzed in the context of noncommutative
geometry where we show that spontaneous parity violation is ruled out.

</DOC>
<DOC>
<DOCNO> 85550 </DOCNO>
Essentials of Classical Brane Dynamics


  This article provides a self contained overview of the geometry and dynamics
of relativistic brane models, of the category that includes point particle,
string, and membrane representations for phenomena that can be considered as
being confined to a worldsheet of the corresponding dimension (respectively
one, two, and three) in a thin limit approximation in an ordinary 4 dimensional
spacetime background. This category also includes ``brane world'' models that
treat the observed universe as a 3-brane in 5 or higher dimensional background.
The first sections are concerned with purely kinematic aspects: it is shown
how, to second differential order, the geometry (and in particular the inner
and outer curvature) of a brane worldsheet of arbitrary dimension is
describable in terms of the first, second, and third fundamental tensor. The
later sections show how -- to lowest order in the thin limit -- the evolution
of such a brane worldsheet will always be governed by a simple tensorial
equation of motion whose left hand side is the contraction of the relevant
surface stress tensor $ bar T^{\mu\nu}$ with the (geometrically defined) second
fundamental tensor $K_{\mu\nu}{^\rho}$, while the right hand side will simply
vanish in the case of free motion and will otherwise be just the orthogonal
projection of any external force density that may happen to act on the brane.

</DOC>
<DOC>
<DOCNO> 69085 </DOCNO>
Total Cross Sections with Virtual Photons


  A model for total cross sections with virtual photons is presented, in
particular gamma-p and gamma-gamma cross sections are considered. Our approach
is based on an existing model for photoproduction, which subdivides the total
cross section into three distinct event classes: direct, VMD and anomalous. In
the region of large photon virtualities, the Deep Inelastic Scattering
processes (up to O(alpha_s) corrections) are obtained. Hence, the model
provides a smooth transition between the two regions. By the breakdown into
different event classes, a complete picture of all event properties is the
ultimate goal.

</DOC>
<DOC>
<DOCNO> 71684 </DOCNO>
Status of ring-like correlations and wavelets


  The problem of large-scale correlations of particles produced in high-energy
collisions is discussed. Among them are, e.g., those correlations which lead to
ring-like and elliptic flow shapes of individual high-multiplicity events in
the polar+azimuthal angles plane. The wavelet method of analysis which allows
to disentangle various patterns is proposed and applied to central Pb-Pb
collisions at 158A GeV.

</DOC>
<DOC>
<DOCNO> 85629 </DOCNO>
Consequences on variable Lambda-models from distant Type Ia supernovae


  We study the m-z relation for Type Ia supernovae data and the \theta-z
relation for the updated compact radio sources data in 4 variable \Lambda-
models: \Lambda \sim S^{-2}, \Lambda \sim H^2, \Lambda \sim \rho and \Lambda
\sim t^{-2}.
  It is found that all the models fit the data sets equally well and require
non-zero, positive values of \Lambda. The supernovae data favour an
accelerating expansion of the universe whereas the radio sources data imply
either sign of the deceleration parameter. The estimates of the density
parameter for the variable \Lambda-models are found higher than those for the
constant \Lambda-Friedmann model. It is also found that the Gurvits et al'
model (FRW model with \Lambda=0) is not the best-fitting model for the constant
\Lambda case. The best-fitting Friedmann model (with constant \Lambda) is found
to be a low density, vacuum-dominated accelerating universe. However, for
realistic values of the matter density parameter, the only interesting
solutions are (a) estimated from the supernovae data: the best-fit solutions
for the flat models (including the constant \Lambda case); (b) estimated from
the radio sources data: the global best-fit solutions for the models \Lambda
\sim H^2 and \Lambda \sim \rho, the best-fit solution for the flat model with
\Lambda=constant and the Gurvits et al' model.
  It is noted that, as in the case of recent CMB analyses, the data sets seem
to favour a spherical universe (k>0).

</DOC>
<DOC>
<DOCNO> 10429 </DOCNO>
Broken Symmetry, Boundary Conditions, and Band Gap Oscillations in


  We have shown how the interplay between the broken symmetry associated with
the finite single-wall nanotubes (SWNT) and the boundary conditions affects the
electronic properties of SWNTs in a profound way. For finite SWNTs (p,q)
characterized by p=k+l,q=k-l,p-q=2l,l=0,1...,k, and k=1,2..., we found that the
band gaps of finite SWNTs belonging to a certain k exhibit similar well-defined
oscillating patterns but with diminishing amplitudes from the armchair (l=0) to
the zigzag (l=k) SWNTs. These profound changes hold intiguing implications in
the potential utilization of these finite NTs as the basic component of
molecular scale devices.

</DOC>
<DOC>
<DOCNO> 119852 </DOCNO>
Tidal Tails Around 20 Galactic Globular Cluster: Observational Evidence


  Large-field multi-color images of 20 galactic globular clusters are used to
investigate the presence of tidal tails around these stellar systems. Field and
cluster stars are sorted with the help of color-magnitude diagrams, and
star-count analysis is performed on the selected cluster stars in order to
increase the signal-to-noise ratio of their surface density. We study the
overdensities of these stars using the wavelet transform of the star counts in
order to filter the background density noise and to detect the weak structures,
at large scale, formed by the numerous stars previously members of the
clusters. We associate these stellar overdensities with the stars evaporated
from the clusters because of dynamical relaxation and/or tidal stripping from
the clusters by the galactic gravitational field. Most of the globular clusters
in our sample display strong evidence of tidal interactions with the galactic
plane in the form of large and extended deformations. These tidal tails exhibit
projected directions preferentially towards the galactic center. All the
clusters observed, which do not suffer from strong observational biases,
present such tidal tails, tracing their dynamical evolution (evaporation, tidal
shocking, tidal torquing, and bulge shocking) in the Galaxy. The clusters
exhibit different regimes of mass loss rate, detected using the radial density
slope in the outer parts of the clusters. For NGC 5139 ($\omega$ Centauri), we
estimate, taking into account the possible presence of mass segregation in its
outer parts, that about 0.6 to 1% of its mass has been lost during the crossing
(Abridged)

</DOC>
<DOC>
<DOCNO> 121683 </DOCNO>
The Sunyaev-Zeldovich MITO Project


  Compton scattering of the cosmic microwave background radiation by electrons
in the hot gas in clusters of galaxies - the Sunyaev-Zeldovich effect - has
long been recognized as a uniquely important feature, rich in cosmological and
astrophysical information. We briefly describe the effect, and emphasize the
need for detailed S-Z and X-ray measurements of nearby clusters in order to use
the effect as a precise cosmological probe. This is the goal of the MITO
project, whose first stage consisted of observations of the S-Z effect in the
Coma cluster. We report the results of these observations.

</DOC>
<DOC>
<DOCNO> 120693 </DOCNO>
Four Years of Extreme Ultraviolet Observations of Markarian 421. I:


  We analyzed the ~950 ks of spectroscopic data accumulated by the Extreme
Ultraviolet Explorer (EUVE) satellite between 1994 and 1997 for the BL Lacertae
object Markarian 421. The EUV spectrum is well detected in the 70-110 A
(112-177 eV) range and can be fitted by a power law model plus an absorption
feature in the ~71-75 A range. Previous studies of EUV absorption features in
MRK 421 and in the other EUV bright BL Lac object, PKS2155-304, explain this
absorption feature as a superposition of Doppler-smeared absorption lines
(mainly L- and M-shell transitions of Mg and Ne) originating in high-velocity
gas clouds ionized by the beamed continuum of the associated relativistic jet.
We show that, for example, Fe IX L could also be a possibility consistent with
the marginal detection of oxygen absorption lines in the X-ray range. However
physical models are highly sensitive to the assumptions on the photoionizing
continuum and the surrounding gas.

</DOC>
<DOC>
<DOCNO> 69904 </DOCNO>
Topology of the Las Campanas Redshift Survey


  The topology of the Las Campanas Redshift Survey is analyzed using Minkowski
functional statistics, taking into account the selection effects of the survey.
The results are compared with the predictions of some toy models of structure
formation, including the Standard Cold Dark Matter Model and topological
defect-based models. All of the toy models have a scale invariant primordial
spectrum of perturbations, but quite different topologies. The statistics can
discriminate between the predictions of the models with high significance.
Amongst the four Minkowski functionals, the integrated mean curvature statistic
appears to be the most powerful discriminant, followed by the genus statistic.
None of the models considered gives an acceptable fit to the data.

</DOC>
<DOC>
<DOCNO> 122851 </DOCNO>
The Seyfert-Starburst Connection in X-rays. II. Results and Implications


  We present the results of X-ray imaging and spectroscopic analysis of a
sample of Seyfert 2 galaxies that contain starbursts, based on their optical
and UV characteristics. These composite galaxies exhibit extended, soft,
thermal X-ray emission, which we attribute to their starburst components.
Comparing their X-ray and far-infrared properties with ordinary Seyfert and
starburst galaxies, we identify the spectral characteristics of their various
intrinsic emission sources. The observed far-infrared emission of the composite
galaxies may be associated almost exclusively with star formation, rather than
the active nucleus. The ratio of the hard X-ray luminosity to the far-infrared
and [O III] 5007 luminosity distinguishes most of these composite galaxies from
``pure'' Seyfert 2 galaxies, while their total observed hard X-ray luminosity
distinguishes them from ``pure'' starbursts. The hard nuclear X-ray source is
generally heavily absorbed (N_H > 10^{23} cm^{-2}) in the composite galaxies.
Based on these results, we suggest that the interstellar medium of the nuclear
starburst is a significant source of absorption. The majority of the sample are
located in groups or are interacting with other galaxies, which may trigger the
starburst or allow rapid mass infall to the central black hole, or both. We
conclude that starbursts are energetically important in a significant fraction
of active galaxies, and starbursts and active galactic nuclei may be part of a
common evolutionary sequence.

</DOC>
<DOC>
<DOCNO> 70950 </DOCNO>
New mechanism for the generation of primordial seeds for the cosmic


  We discuss the inflationary production of magnetic seeds for the galactic
dynamo through the photon-graviphoton mixing typical of extended models of
local supersymmetry. An analisys of the allowed region in parameter space shows
that such a mechanism is compatible with existing phenomenological bounds on
the vector mass and on the mixing parameter, but requires a large enough mixing
that seems difficult to implement naturally in the context of a minimal
supersymmetric scenario.

</DOC>
<DOC>
<DOCNO> 84889 </DOCNO>
Non-time-orthogonality and Tests of Special Relativity


  An intriguing, and possibly significant, anomalous signal in the Brillet and
Hall experiment is contrasted with a simple first order test of special
relativity subsequently performed to discount that signal as spurious. Analysis
of the non-time-orthogonal nature of the rotating earth frame leads to the
conclusion that the latter test needed second order accuracy in order to detect
the effect sought, and hence was not sufficient to discount the potential cause
of the anomalous signal. The analysis also explains the results found in Sagnac
type experiments wherein different media were placed in the path of the light
beams.

</DOC>
<DOC>
<DOCNO> 118621 </DOCNO>
Non-Gaussian signature induced by the SZ effect of galaxy clusters


  We apply statistical tests, based on the study of thecoefficients in a
wavelet decomposition, to a cosmological signal: the Cosmic Microwave
Background (CMB) anisotropies. The latter represent the superposition of
primary anisotropy imprints of the initial density perturbations and secondary
anisotropies due to photon interactions after recombination. In an inflationary
scenario with Gaussian distributed fluctuations, we study the statistical
signature of the secondary effects. More specifically, we investigate the
dominant effects arising from the Sunyaev-Zel'dovich effect of galaxy clusters.
Our study predicts the non-Gaussian signature of these secondary anisotropies
and its detectability in the context of the future CMB satellite Planck
Surveyor.

</DOC>
<DOC>
<DOCNO> 102769 </DOCNO>
Invitation to higher local fields, Part I, section 4: Cohomological


  This is a sketch of main steps of the proof of Bloch--Kato's theorem which
states that the norm residue homomorphism
             K_q(K)/m\to H^q(K,\Bbb Z/m(q)) is an isomorphism for a henselian
discrete valuation field K of characteristic 0 with residue field of positive
characteristic.

</DOC>
<DOC>
<DOCNO> 150769 </DOCNO>
The String Dual of a Confining Four-Dimensional Gauge Theory


  We study N=1 gauge theories obtained by adding finite mass terms to N=4
Yang-Mills theory. The Maldacena dual is nonsingular: in each of the many
vacua, there is an extended brane source, arising from Myers' dielectric
effect. The source consists of one or more (p,q) 5-branes. In particular, the
confining vacuum contains an NS5-brane; the confining flux tube is a
fundamental string bound to the 5-brane. The system admits a simple
quantitative description as a perturbation of a state on the N=4 Coulomb
branch. Various nonperturbative phenomena, including flux tubes, baryon
vertices, domain walls, condensates and instantons, have new, quantitatively
precise, dual descriptions. We also briefly consider two QCD-like theories. Our
method extends to the nonsupersymmetric case. As expected, the N=4 matter
cannot be decoupled within the supergravity regime.

</DOC>
<DOC>
<DOCNO> 68023 </DOCNO>
Metric Unification of Gravitation and Electromagnetism Solves the


  We first review the cosmological constant problem, and then mention a
conjecture of Feynman according to which the general relativistic theory of
gravity should be reformulated in such a way that energy does not couple to
gravity. We point out that our recent unification of gravitation and
electromagnetism through a symmetric tensor has the property that the free
electromagnetic energy and the vacuum energy do not contribute explicitly to
the curvature of spacetime just like the free gravitational energy. Therefore
in this formulation of general relativity, the vacuum energy density has its
very large value today as in the early universe, while the cosmological
constant does not exist at all.

</DOC>
<DOC>
<DOCNO> 100608 </DOCNO>
Dirac operators and conformal invariants of tori in 3-space


  We show how to assign to any immersed torus in $\R^3$ or $S^3$ a Riemann
surface such that the immersion is described by functions defined on this
surface. We call this surface the spectrum or the spectral curve of the torus.
The spectrum contains important information about conformally invariant
properties of the torus and, in particular, relates to the Willmore functional.
We propose a simple proof that for isothermic tori in $\R^3$ (this class
includes constant mean curvature tori and tori of revolution) the spectrum is
invariant with respect to conformal transformations of $\R^3$. We show that the
spectral curves of minimal tori in $S^3$ introduced by Hitchin and of constant
mean curvature tori in $\R^3$ introduced by Pinkall and Sterling are particular
cases of this general spectrum. The construction is based on the Weierstrass
representation of closed surfaces in $\R^3$ and the construction of the
Floquet--Bloch varieties of periodic differential operators.

</DOC>
<DOC>
<DOCNO> 8934 </DOCNO>
Nonlinear evolution of the momentum dependent condensates in strong


  We discuss the relaxation of the scalar and pseudoscalar condensates after a
rapid quench from an initial state with fluctuations. If we include not only
the zero-mode but also higher modes of the condensates in the classical
evolution, we observe parametric amplification of those ``hard'' modes. Thus,
they couple nonlinearly to the ``soft'' modes. As a consequence, domains of
coherent pi-field emerge long after the initial spinodal decomposition. The
momentum-space distribution of pions emerging from the decay of that
momentum-dependent condensate is discussed.

</DOC>
<DOC>
<DOCNO> 12602 </DOCNO>
Phonons and Phonon Confinement in Transport through Double Quantum Dots


  We calculate the electron-phonon interaction coefficients for surface
acoustic waves and for phonons in free standing quantum wells. These are used
to derive the inelastic current through a double quantum dot caused by
spontaneous emission of phonons. For the case of the free standing structure
(phonon cavity), we predict a staircase-like inelastic current superimposed by
van Hove singularities. Therefore, the phonon confinement can be detected by
electron transport measurements.

</DOC>
<DOC>
<DOCNO> 117252 </DOCNO>
The generation of gravitational waves


  A proof that the generation of gravitational waves is physically impossible.

</DOC>
<DOC>
<DOCNO> 70941 </DOCNO>
Large metric perturbations from rescattering


  We study numerically evolution of metric perturbations during reheating in a
model with two fields and a strong parametric resonance. Our calculation is
fully nonlinear and includes gravity but is restricted to spherical symmetry.
In this model, super-Hubble metric perturbations can grow during reheating only
due to effects nonlinear in fluctuations of the fields. We find that they
indeed grow and, soon after the growth begins, dominate variances of the metric
functions. Thus, the metric functions become smooth but varying significantly
over large scales. Their profiles at late times are interpreted as signalling a
gravitational instability and formation of a black hole.

</DOC>
<DOC>
<DOCNO> 9023 </DOCNO>
Universality of the Kondo Effect in a Quantum Dot out of Equilibrium


  We study the Kondo effect in a quantum dot driven out of equilibrium by an
external ac field. The Kondo effect can be probed by measuring the dc current
induced by an auxiliary dc bias $V_{dc}$ applied across the dot. In the absence
of ac perturbation, the corresponding differential conductance $G(V_{dc})$ is
known to exhibit a sharp peak at $V_{dc}=0$, which is the manifestation of the
Kondo effect. In the equilibrium, there exists only one energy scale, the Kondo
temperature $T_K$, which controls all the low-energy physics of the system; $G$
is some universal function of $eV_{dc}/T_K$. We demonstrate that the dot out of
equilibrium is also characterized by a universal behavior: conductance $G$
depends on the ac field only through two dimensionless parameters, which are
the frequency $\omega$ and the amplitude of the ac perturbation, both divided
by $T_K$. We find analytically the large- and small-frequency asymptotes of the
universal dependence of $G$ on these parameters. The obtained results allow us
to predict the behavior of the conductance in the crossover regime
$\hbar\omega\sim T_K$.

</DOC>
<DOC>
<DOCNO> 120321 </DOCNO>
A Near-Infrared Stellar Census of Blue Compact Dwarf Galaxies: NICMOS


  We observed the Blue Compact Dwarf/Wolf-Rayet galaxy Mrk 178 with the NICMOS
camera aboard HST. The galaxy is well resolved into individual stars in the
near-IR; photometry in J and H yields color-magnitude diagrams containing 791
individual point sources. We discuss the stellar content, drawing particular
attention to the intermediate age and/or old stars. Mrk 178 is only the second
Blue Compact Dwarf galaxy in which the red giant branch has been resolved,
indicating stars with ages of at least 1-2Gyr. This allows us to derive a
distance of $\geq$4.2($\pm$0.5)Mpc. The near-IR color-magnitude diagram also
exhibits an abundance of luminous, asymptotic giant branch stars. We find that
this requires vigorous star formation several hundred Myr ago. Some candidate
carbon stars are identified via their extreme near-IR color. We argue that
Mrk178 is fundamentally an old galaxy, based on the NICMOS detection of red
giants underlying the blue, starburst core, and its extended, faint halo of
redder color.

</DOC>
<DOC>
<DOCNO> 85456 </DOCNO>
Gauge fixing and the Hamiltonian for cylindrical spacetimes


  We introduce a complete gauge fixing for cylindrical spacetimes in vacuo
that, in principle, do not contain the axis of symmetry. By cylindrically
symmetric we understand spacetimes that possess two commuting spacelike Killing
vectors, one of them rotational and the other one translational. The result of
our gauge fixing is a constraint-free model whose phase space has four
field-like degrees of freedom and that depends on three constant parameters.
Two of these constants determine the global angular momentum and the linear
momentum in the axis direction, while the third parameter is related with the
behavior of the metric around the axis. We derive the explicit expression of
the metric in terms of the physical degrees of freedom, calculate the reduced
equations of motion and obtain the Hamiltonian that generates the reduced
dynamics. We also find upper and lower bounds for this reduced Hamiltonian that
provides the energy per unit length contained in the system. In addition, we
show that the reduced formalism constructed is well defined and consistent at
least when the linear momentum in the axis direction vanishes. Furthermore, in
that case we prove that there exists an infinite number of solutions in which
all physical fields are constant both in the surroundings of the axis and at
sufficiently large distances from it. If the global angular momentum is
different from zero, the isometry group of these solutions is generally not
orthogonally transitive. Such solutions generalize the metric of a spinning
cosmic string in the region where no closed timelike curves are present.

</DOC>
<DOC>
<DOCNO> 8809 </DOCNO>
Proximity effect in planar TiN-Silicon junctions


  We measured the low temperature subgap resistance of titanium nitride
(superconductor, Tc=4.6K)/highly doped silicon (degenerated semiconductor) SIN
junctions, where I stands for the Schottky barrier. At low energies, the subgap
conductance is enhanced due to coherent backscattering of the electrons towards
the interface by disorder in the silicon (''reflectionless tunneling''). This
Zero Bias Anomaly (ZBA) is destroyed by the temperature or the magnetic field
above 250mK or 0.04T respectively. The overall differential resistance behavior
(vs temperature and voltage) is compared to existing theories and values for
the depairing rate and the barrier transmittance are extracted. Such an
analysis leads us to introduce an effective temperature for the electrons and
to discuss heat dissipation through the SIN interface.

</DOC>
<DOC>
<DOCNO> 13059 </DOCNO>
The differential energy distribution of the universal density profile of


  We study the differential energy distribution of dark matter halos, carrying
out cosmological N-body simulation.We give an analytical formula of the
differential energy distribution of dark matter in the halos obtained by the
numerical simulation.From the analytical formula we reconstruct the density
profile described by the Navarro,Frenk, & White (NFW) profile.The NFW profile
is consistent with the analytical formula of our fractional mass distribution.
We find that a parameter in our analytical formula of differential energy
distribution which is related with the slope of inner cusp of dark halo.We
obtain the distribution function for the NFW profile which has sharp cut off at
the high binding energy.We discuss physical reason of form of the analytical
formula.

</DOC>
<DOC>
<DOCNO> 116902 </DOCNO>
Estimates of dispersive effects in a bent NLC main linac


  An alternative being considered for the Next Linear Collider (NLC) is not to
tunnel in a straight line but to bend the Main Linac into an arc so as to
follow an equipotential. We begin here an examination of the effects that this
would have on vertical dispersion, with its attendant consequences on
synchrotron radiation and emittance growth by looking at two scenarios: a
gentle continuous bending of the beam to follow an equipotential surface, and
an introduction of sharp bends at a few sites in the linac so as to reduce the
maximum sagitta produced.

</DOC>
<DOC>
<DOCNO> 13954 </DOCNO>
Equilibrium Configurations and Energetics of Point Defects in


  We demonstrate a novel method of introducing point defects (mono and
di-vacancies) in a confined mono-layer colloidal crystal by manipulating
individual particles with optical tweezers. Digital video microscopy is used to
study defect dynamics in real space and time. We analyze the topological
arrangements of the particles in the defect core and establish their connection
with the energetics of the system. It is found that thermal fluctuations excite
point defects into \textit{dislocation multipole} configurations. We extract
the dislocation pair potential at near field, where cores overlap and linear
elasticity is not applicable.

</DOC>
<DOC>
<DOCNO> 69576 </DOCNO>
Supersymmetric Effects on Isospin Symmetry Breaking and Direct CP


  We argue that one can search for physics beyond the standard model through
measurements of the isospin-violating quantity $\Delta^{-0} \equiv \Gamma(B^-
\to \rho^- \gamma)/2\Gamma(B^0 \to \rho^0 \gamma)-1$, its charge conjugate
$\Delta^{+0}$, and direct CP violation in the partial decay rates of $B^\pm \to
\rho^\pm \gamma$. We illustrate this by working out theoretical profiles of the
charge-conjugate averaged ratio $\Delta \equiv {1 \over 2}(\Delta^{+0}
+\Delta^{-0})$ and the CP asymmetry $A_{CP}(B^\pm \to \rho^\pm \gamma)$ in the
standard model and in some variants of the minimal supersymmetric standard
model. We find that chargino contributions in the large $\tan \beta$ region may
modify the magnitudes and flip the signs of $\Delta$ and $A_{CP}(B^\pm \to
\rho^\pm \gamma)$ compared to their standard-model values, providing an
unmistakeable signature of supersymmetry.

</DOC>
<DOC>
<DOCNO> 151007 </DOCNO>
Consistent Linearized Gravity in Brane Backgrounds


  A globally consistent treatment of linearized gravity in the Randall-Sundrum
background with matter on the brane is formulated. Using a novel gauge, in
which the transverse components of the metric are non-vanishing, the brane is
kept straight. We analyze the gauge symmetries and identify the physical
degrees of freedom of gravity. Our results underline the necessity for
non-gravitational confinement of matter to the brane.

</DOC>
<DOC>
<DOCNO> 151269 </DOCNO>
Dynamical Symmetry Breaking and Magnetic Confinement in QCD


  We present a gauge independent method to construct the effective action of
QCD, and calculate the one loop effective action of $SU(2)$ QCD in an arbitrary
constant background field. Our result establishes the existence of a dynamical
symmetry breaking by demonstrating that the effective potential develops a
unique and stable vacuum made of the monopole condensation in one loop
approximation. This provides a strong evidence for the magnetic confinement of
color through the dual Meissner effect in the non-Abelian gauge theory. The
result is obtained by separating the topological degrees which describe the
non-Abelian monopoles from the dynamical degrees of the gauge potential, and
integrating out all the dynamical degrees of QCD. We present three independent
arguments to support our result.

</DOC>
<DOC>
<DOCNO> 9555 </DOCNO>
Covariant Vortex In Superconducting-Superfluid-Normal Fluid Mixtures


  The integrals of motion for a cylindrically symmetric stationary vortex are
obtained in a covariant description of a mixture of interacting
superconductors, superfluids and normal fluids. The relevant integrated
stress-energy coefficients for the vortex with respect to a vortex-free
reference state are calculated in the approximation of a ``stiff'', i.e. least
compressible, relativistic equation of state for the fluid mixture. As an
illustration of the foregoing general results, we discuss their application to
some of the well known examples of ``real'' superfluid and superconducting
systems that are contained as special cases. These include Landau's two-fluid
model, uncharged binary superfluid mixtures, rotating conventional
superconductors and the superfluid neutron-proton-electron plasma in the outer
core of neutron stars.

</DOC>
<DOC>
<DOCNO> 120978 </DOCNO>
Response of circumnuclear water masers to luminosity changes in an


  Circumnuclear water masers can respond in two ways to changes in the
luminosity of an active galactic nucleus. First, an increase in the X-ray
luminosity can lead to an increase in the maser emissivity; and second, an
increase in the intrinsic bolometric luminosity may result in a temporary
decrease in the difference between the gas and dust temperature and a
consequent decrease in the maser output. Whilst the latter effect can occur
over a period shorter than the thermal timescale, the former effect cannot.
Quantitative estimates of the response of the water maser emissivity to changes
in either the X-ray or bolometric luminosity are presented, together with
estimates of the relevant timescales. Either mechanism could account for recent
observations by Gallimore et al. which suggest that the water maser variability
in two widely separated regions of the circumnuclear gas in NGC 1068 have been
coordinated by a signal from the active nucleus. For either mechanism, a
minimum H2 density ~ 1.E+8 cm-3 is needed to explain the observed variability
timescale.

</DOC>
<DOC>
<DOCNO> 7933 </DOCNO>
Condensate growth in trapped Bose gases


  We study the dynamics of condensate formation in an inhomogeneous trapped
Bose gas with a positive interatomic scattering length. We take into account
both the nonequilibrium kinetics of the thermal cloud and the Hartree-Fock
mean-field effects in the condensed and the noncondensed parts of the gas. Our
growth equations are solved numerically by assuming that the thermal component
behaves ergodically and that the condensate, treated within the Thomas-Fermi
approximation, grows adiabatically. Our simulations are in good qualitative
agreement with experiment, however important discrepancies concerning details
of the growth behaviour remain.

</DOC>
<DOC>
<DOCNO> 151857 </DOCNO>
On the notion of potential in quantum gravity


  The problem of consistent definition of the quantum corrected gravitational
field is considered in the framework of the $S$-matrix method. Gauge dependence
of the one-particle-reducible part of the two-scalar-particle scattering
amplitude, with the help of which the potential is usually defined, is
investigated at the one-loop approximation. The $1/r^2$-terms in the potential,
which are of zero order in the Planck constant $\hbar,$ are shown to be
independent of the gauge parameter weighting the gauge condition in the action.
However, the $1/r^3$-terms, proportional to $\hbar,$ describing the first
proper quantum correction, are proved to be gauge-dependent. With the help of
the Slavnov identities, their dependence on the weighting parameter is
calculated explicitly. The reason the gauge dependence originates from is
briefly discussed.

</DOC>
<DOC>
<DOCNO> 101545 </DOCNO>
On Conley's Fundamental Theorem of Dynamical Systems


  In this paper, we generalize Conley's fundamental theorem of dynamical
systems in Conley index theory. We also conclude the existence of regular index
filtration for every Morse decomposition.

</DOC>
<DOC>
<DOCNO> 101467 </DOCNO>
The modelling and analysis of fractional-order control systems in


  This paper deals with fractional-order controlled systems and
fractional-order controllers in the frequency domain. The mathematical
description by fractional transfer functions and properties of these systems
are presented. The new ways for modelling of fractional-order systems are
illustrated with a numerical example and obtained results are discussed in
conclusion.

</DOC>
<DOC>
<DOCNO> 13888 </DOCNO>
Direct observation of molecular cooperativity near the glass transition


  We describe direct observations of molecular cooperativity near the glass
transition in poly-vinyl-acetate (PVAc), through nanometer-scale probing of
dielectric fluctuations. Molecular clusters switched spontaneously between two
to four distinct configurations, producing complex random-telegraph-signals
(RTS). Analysis of the RTS and their power spectra shows that individual
clusters exhibit both transient dynamical heterogeneity and non-exponential
kinetics.

</DOC>
<DOC>
<DOCNO> 69396 </DOCNO>
The Trans-Planckian Problem of Inflationary Cosmology


  In most current models of inflation based on a weakly self-coupled scalar
matter field minimally coupled to gravity, the period of inflation lasts so
long that, at the beginning of the inflationary period, the physical
wavelengths of comoving scales which correspond to the present large-scale
structure of the Universe were smaller than the Planck length. Thus, the usual
computations of the spectrum of fluctuations in these models involve
extrapolating low energy physics (both in the matter and gravitational sector)
into regions where this physics is not applicable. In this paper we demonstrate
that the usual predictions of inflation for the spectrum of cosmological
fluctuations do indeed depend on the hidden assumptions about super-Planck
scale physics. We introduce a class of modified dispersion relations to mimic
possible effects of super-Planck scale physics, and show that in some cases
important deviations from the usual predictions of inflation are obtained. Some
implications of this result for the unification of fundamental physics and
early Universe cosmology are discussed.

</DOC>
<DOC>
<DOCNO> 118521 </DOCNO>
Observations of Eddington-limited type-I X-ray bursts from 4U 1812-12


  During more than 3 years (August 1996-October 1999) monitoring of a 40x40
degree sky region around the Galactic Centre by the Wide Field Cameras on board
BeppoSAX, a total of 8 type-I bursts have been detected from a sky position
consistent with that of 4U 1812-12, a likely neutron-star low-mass X-ray
binary. We present the results of a detailed study of the bursts of 4U 1812-12,
about 15 years after the last reported observations of X-ray bursts from this
source (Murakami et al. 1983). Clear evidence for photospheric radius expansion
due to Eddington-limited burst luminosity is present in most of the observed
events, allowing an accurate estimate of the source distance (~4 kpc) and its
burst parameters.

</DOC>
<DOC>
<DOCNO> 11243 </DOCNO>
Stability of stationary states in the cubic nonlinear Schroedinger


  The stability properties and perturbation-induced dynamics of the full set of
stationary states of the nonlinear Schroedinger equation are investigated
numerically in two physical contexts: periodic solutions on a ring and
confinement by a harmonic potential. Our comprehensive studies emphasize
physical interpretations useful to experimentalists. Perturbation by stochastic
white noise, phase engineering, and higher order nonlinearity are considered.
We treat both attractive and repulsive nonlinearity and illustrate the
soliton-train nature of the stationary states.

</DOC>
<DOC>
<DOCNO> 9869 </DOCNO>
Low-Temperature Magnetic Penetration Depth in d-Wave Superconductors:


  We report a theoretical study on the deviations of the Meissner penetration
depth $\lambda(T)$ from its London value in d-wave superconductors at low
temperatures. The difference arises from low-energy surface Andreev bound
states. The temperature dependent penetration depth is shown to go through a
minimum at the temperature $T_{m0}\sim \sqrt{\xi_0/\lambda_0}T_c$ if the
broadening of the bound states is small. The minimum will straighten out when
the broadening reaches $T_{m0}$. The impurity scattering sets up the
low-temperature anomalies of the penetration depth and destroys them when the
mean free path is not sufficiently large. A phase transition to a state with
spontaneous surface supercurrent is investigated and its critical temperature
determined in the absence of a subdominant channel activated at low
temperatures near the surface. Nonlinear corrections from Andreev low-energy
bound states to the penetration length are obtained and shown, on account of
their broadening, to be small in the Meissner state of strong type II
superconductors.

</DOC>
<DOC>
<DOCNO> 101001 </DOCNO>
Unknotting virtual knots with Gauss diagram forbidden moves


  The forbidden moves can be combined with Gauss diagram Reidemeister moves to
obtain move sequences with which we may change any Gauss diagram (and hence any
virtual knot) into any other, including in particular the unknotted diagram

</DOC>
<DOC>
<DOCNO> 101473 </DOCNO>
The Witten genus and equivariant elliptic cohomology


  We construct a Thom class in complex equivariant elliptic cohomology
extending the equivariant Witten genus. This gives a new proof of the rigidity
of the Witten genus, which exhibits a close relationship to recent work on
non-equivariant orientations of elliptic spectra.

</DOC>
<DOC>
<DOCNO> 101750 </DOCNO>
Classical Equation of Gravity to Quantum Limit


  The fact that mass has an effect on surrounding space is the first essential
element of general relativity. This paper unifies this mass/space distinction
of general relativity with Newtonian gravity at a subatomic scale and with
reported experimental findings of the last century. The subatomic distinction
of mass concentration mainly in nucleons surrounded by empty space as we know
it now was not known when the general relativity was written. The author uses
this distinction to set forth a consistent classical equation of gravity valid
to the Planck length and peeps into the quantum world. It is difficult to
exaggerate the importance of fundamental nuclear theory for the understanding
of matter in the universe and its cosmological evaluation, and also for the
inclusion of gravity in the unified family of all four forces.

</DOC>
<DOC>
<DOCNO> 170667 </DOCNO>
Bounds on the generalized entanglement of formation for multi-party


  We present a general method to find the upper and lower bounds on the
generalized entanglement of formation for multi-party systems. The upper and
lower bounds can be expressed in terms of the bi-partite entanglements of
formation and/or entropies of various subsystems. The examples for tri- and
four-party systems in the both pure states and mixed states are given. We also
suggest a little modified definition of generalized entanglement of formation
for multi-party systems if EPR pairs are thought of belonging to the set of
maximally entangled states.

</DOC>
<DOC>
<DOCNO> 118674 </DOCNO>
Magnetic Photon Splitting: the S-Matrix Formulation in the Landau


  Calculations of reaction rates for the third-order QED process of photon
splitting in strong magnetic fields traditionally have employed either the
effective Lagrangian method or variants of Schwinger's proper-time technique.
Recently, Mentzel, Berg and Wunner (1994) presented an alternative derivation
via an S-matrix formulation in the Landau representation. Advantages of such a
formulation include the ability to compute rates near pair resonances above
pair threshold. This paper presents new developments of the Landau
representation formalism as applied to photon splitting, providing significant
advances beyond the work of Mentzel et al. by summing over the spin quantum
numbers of the electron propagators, and analytically integrating over the
component of momentum of the intermediate states that is parallel to field. The
ensuing tractable expressions for the scattering amplitudes are satisfyingly
compact, and of an appearance familiar to S-matrix theory applications. Such
developments can facilitate numerical computations of splitting considerably
both below and above pair threshold. Specializations to two regimes of interest
are obtained, namely the limit of highly supercritical fields and the domain
where photon energies are far inferior to that for the threshold of
single-photon pair creation. In particular, for the first time the
low-frequency amplitudes are simply expressed in terms of the Gamma function,
its integral and its derivatives. In addition, the equivalence of the
asymptotic forms in these two domains to extant results from effective
Lagrangian/proper-time formulations is demonstrated.

</DOC>
<DOC>
<DOCNO> 152201 </DOCNO>
Finite size effects in perturbed boundary conformal field theories


  We discuss the finite-size properties of a simple integrable quantum field
theory in 1+1 dimensions with non-trivial boundary conditions. Novel
off-critical identities between cylinder partition functions of models with
differing boundary conditions are derived.

</DOC>
<DOC>
<DOCNO> 119226 </DOCNO>
Multi-wavelength Observations of Galaxies in the Southern Zone of


  We discuss the possibilities of extragalactic large-scale studies behind the
Zone of Avoidance (ZOA) using complementary multi-wavelength data from optical,
systematic blind HI, and near-infrared (NIR) surveys. Applying these data to
the NIR Tully-Fisher relation permits the mapping of the peculiar velocity
field across the ZOA. Here, we present results of a comparison of galaxies
identified in the rich low-latitude cluster Abell 3627 in the B-band with NIR
(DENIS) data, and cross-identifications of galaxies detected with the blind
Parkes HI Multibeam survey with NIR data - many of which are optically
invisible.

</DOC>
<DOC>
<DOCNO> 40188 </DOCNO>
A New High Energy Photon Tagger for the H1 - Detector at HERA


  The H1 detector at HERA has been upgraded by the addition of a new
electromagnetic calorimeter. This is installed in the HERA tunnel close to the
electron beam line at a position 8m from the interaction point in the electron
beam direction. The new calorimeter extends the acceptance for tagged
photoproduction events to the high y range, 0.85 < y < 0.95, and thus
significantly improves the capability of H1 to study high energy gamma-p
processes. The calorimeter design, performance and first results obtained
during the 1996-1999 HERA running are described.

</DOC>
<DOC>
<DOCNO> 118541 </DOCNO>
Rearrangement of the Fermi Surface of Dense Neutron Matter and Direct


  It is proposed that a rearrangement of single-particle degrees of freedom may
occur in a portion of the quantum fluid interior of a neutron star. Such a
rearrangement is associated with the pronounced softening of the spin-isospin
collective mode which, under increasing density, leads to pion condensation.
Arguments and estimates based on fundamental relations of many-body theory show
that one realization of this phenomenon could produce very rapid cooling of the
star via a direct nucelon Urca process displaying a $T^5$ dependence on
temperature.

</DOC>
<DOC>
<DOCNO> 102289 </DOCNO>
A Wigner-type theorem in Banach spaces


  We obtain an anlogue of Wigner's classical theorem on symmetries for Banach
spaces. The proof is based on a result from the theory of linear preservers.
Moreover, we present two other Wigner-type results for finite dimensional
linear spaces over general fields.

</DOC>
<DOC>
<DOCNO> 100906 </DOCNO>
Faithful Linear Representations of the Braid Groups


  We give an exposition of the work of Bigelow and Krammer who proved that the
Artin braid groups are linear.

</DOC>
<DOC>
<DOCNO> 13937 </DOCNO>
Nonequilibrium dynamics of random field Ising spin chains: exact results


  Non-equilibrium dynamics of classical random Ising spin chains are studied
using asymptotically exact real space renormalization group. Specifically the
random field Ising model with and without an applied field (and the Ising spin
glass (SG) in a field), in the universal regime of a large Imry Ma length so
that coarsening of domains after a quench occurs over large scales. Two types
of domain walls diffuse in opposite Sinai random potentials and mutually
annihilate. The domain walls converge rapidly to a set of system-specific
time-dependent positions {\it independent of the initial conditions}. We obtain
the time dependent energy, magnetization and domain size distribution
(statistically independent). The equilibrium limits agree with known exact
results. We obtain exact scaling forms for two-point equal time correlation and
two-time autocorrelations. We also compute the persistence properties of a
single spin, of local magnetization, and of domains. The analogous quantities
for the spin glass are obtained. We compute the two-point two-time correlation
which can be measured by experiments on spin-glass like systems. Thermal
fluctuations are found to be dominated by rare events; all moments of truncated
correlations are computed. The response to a small field applied after waiting
time $t_w$, as measured in aging experiments, and the fluctuation-dissipation
ratio $X(t,t_w)$ are computed. For $(t-t_w) \sim t_w^{\hat{\alpha}}$,
$\hat{\alpha} <1$, it equals its equilibrium value X=1, though time
translational invariance fails. It exhibits for $t-t_w \sim t_w$ aging regime
with non-trivial $X=X(t/t_w) \neq 1$, different from mean field.

</DOC>
<DOC>
<DOCNO> 118271 </DOCNO>
Neutrino Pair Annihilation in the Gravitation of Gamma Ray Burst Sources


  We study semianalytically the gravitational effects on neutrino pair
annihilation near the neutrinosphere and around the thin accretion disk. For
the disk case, we assume that the accretion disk is isothermal and that the
gravitational field is dominated by the Schwarzschild black hole. General
relativistic effects are studied only near the rotation axis. The energy
deposition rate is enhanced by the effect of orbital bending toward the center.
However, the effects of the redshift and gravitational trapping of the
deposited energy reduce the effective energy of the gamma ray bursts' source.
Although each effect is substantial, the effects partly cancel one another. As
a result, the gravitational effects do not substantially change the energy
deposition rate for either the spherical symmetric case or the disk case.

</DOC>
<DOC>
<DOCNO> 100555 </DOCNO>
On the construction of some Buchsbaum varieties and the Hilbert scheme


  We study the degeneracy loci of general bundle morphisms from the direct sum
of m copies of the structural sheaf on $P^n$ to $\Omega(2)$, also from the
point of view of the classical geometrical interpretation of the sections of
$\Omega(2)$ as linear line complexes. We consider in particular the case of
$P^5$ with m=2, 3. For n=5 and m=3 we give an explicit description of the
Hilbert scheme H of elliptic normal scrolls in $P^5$, by defining a natural
rational map from the Grassmannian G(2,14) to H, which results to be dominant
with general fibre of degree four.

</DOC>
<DOC>
<DOCNO> 11364 </DOCNO>
X-ray Resonant Scattering Studies of Orbital and Charge Ordering in


  We present the results of a systematic x-ray scattering study of the charge
and orbital ordering in the manganite series Pr$_{1-x}$Ca$_x$MnO$_3$ with
$x$=0.25, 0.4 and 0.5. The temperature dependence of the scattering at the
charge and orbital wavevectors, and of the lattice constants, was characterized
throughout the ordered phase of each sample. It was found that the charge and
orbital order wavevectors are commensurate with the lattice, in striking
contrast to the results of earlier electron diffraction studies of samples with
$x$=0.5. High momentum-transfer resolution studies of the x=0.4 and 0.5 samples
further revealed that while long-range charge order is present, long-range
orbital order is never established. Above the charge/orbital ordering
temperature T$_o$, the charge order fluctuations are more highly correlated
than the orbital fluctuations. This suggests that charge order drives orbital
order in these samples. In addition, a longitudinal modulation of the lattice
with the same periodicity as the charge and orbital ordering was discovered in
the x=0.4 and 0.5 samples. For x=0.25, only long-range orbital order was
observed with no indication of charge ordering, nor of an additional lattice
modulation. We also report the results of a preliminary investigation of the
loss of charge and orbital ordering in the x=0.4 sample by application of a
magnetic field. Finally, the polarization and azimuthal dependence of the
charge and orbital ordering in these compounds is characterized both in the
resonant and nonresonant limits, and compared with the predictions of current
theories. The results are qualitatively consistent with both cluster and LDA+U
calculations of the electronic structure.

</DOC>
<DOC>
<DOCNO> 121178 </DOCNO>
The Effect of the Mass Accretion Rate on the Burst Oscillations in 4U


  We present a comprehensive study of the properties of nearly coherent
brightness oscillations (NCOs) in a large sample of type-I X-ray bursts
observed from low mass X-ray binary 4U 1728-34. We have analyzed ~545ks of data
of this source obtained with the Rossi X-ray Timing Explorer over a 3 year span
from 1996-1999. The data contain 38 bursts, 16 of which show NCOs. We find no
NCOs present when the inferred mass accretion rate of the system is lowest.
Furthermore, we define a measure of the strength of the oscillations and find
that this strength increases with increasing mass accretion rate. This
correlation is particularly evident within bursts detected only a few weeks
apart, and becomes less clear for bursts separated in time by several months to
years. The correlation we find for 4U 1728-34 between the NCOs and the inferred
accretion rate of the system is similar to that found for KS 1731-260 by Muno
et al. (2000), where the NCOs are only present at relatively high mass
accretion rates. However, unlike the case for KS 1731-260, we find an
anti-correlation in the bursts of 4U 1728-34 between the existence of episodes
of photospheric radius expansion and the inferred mass accretion rate of the
system. Moreover, we distinguish between NCOs present in the rise and in the
decay phase of the burst and find that the bursts with NCOs only in the decay
phase occur at intermediate accretion rates, while those with NCOs in both the
rise and the decay phases are concentrated at high inferred mass accretion
rates. We discuss these results in the context of the theory of thermonuclear
bursts and propose intrinsic differences in the neutron stars in KS 1731-260
and 4U 1728-34 as the origin of the different behaviors.

</DOC>
<DOC>
<DOCNO> 116839 </DOCNO>
Elliptical X-Ray Spot Measurement


  The so-called roll bar measurement uses a heavy metal material, optically
thick to x-rays, to form a shadow of the x-ray origination spot. This spot is
where an energetic electron beam interacts with a high Z target. The material
(the "roll bar") is slightly curved to avoid alignment problems. The roll bar
is constructed and positioned so that the x-rays are shadowed in the horizontal
and vertical directions, so information is obtained in two dimensions. If a
beam profile is assumed (or measured by other means), the equivalent x-ray spot
size can be calculated from the x-ray shadow cast by the roll bar. Thus the
ellipticity of the beam can be calculated, assuming the ellipse of the x-ray
spot is aligned with the roll bar. The data is recorded using a scintillator
and gated camera. Data will be presented from measurements using the ETA II
induction LINAC. The accuracy of the measurement is checked using small
elliptical targets.

</DOC>
<DOC>
<DOCNO> 117244 </DOCNO>
Random Scattering by Atomic Density Fluctuations in Optical Lattices


  We investigate hitherto unexplored regimes of probe scattering by atoms
trapped in optical lattices: weak scattering by effectively random atomic
density distributions and multiple scattering by arbitrary atomic
distributions. Both regimes are predicted to exhibit a universal semicircular
scattering lineshape for large density fluctuations, which depend on
temperature and quantum statistics.

</DOC>
<DOC>
<DOCNO> 152498 </DOCNO>
Vacuum polarization in the Schwarzschild spacetime and dimensional


  A massless scalar field minimally coupled to gravity and propagating in the
Schwarzschild spacetime is considered. After dimensional reduction under
spherical symmetry the resulting 2D field theory is canonically quantized and
the renormalized expectation values $< T_{a b} >$ of the relevant
energy-momentum tensor operator are investigated. Asymptotic behaviours and
analytical approximations are given for $< T_{a b} >$ in the Boulware, Unruh
and Hartle-Hawking states. Special attention is devoted to the black-hole
horizon region where the WKB approximation breaks down.

</DOC>
<DOC>
<DOCNO> 152362 </DOCNO>
D-branes in Singular Calabi-Yau n-fold and N=2 Liouville Theory


  Making use of the N=2 Liouville theory and world-sheet techniques, we study
the properties of D-branes wrapped around vanishing SUSY cycles of singular
Calabi-Yau n-folds (n=2,3,4). After constructing boundary states describing the
wrapped branes, we evaluate the disc amplitudes corresponding to the periods of
SUSY cycles. We use the old technique of KPZ scaling in Liouville theory and
derive holomorphicity and scaling behavior of vanishing cycles which are in
agreement with geometrical considerations.
  We also discuss the open string Witten index using the N=2 Liouville theory
and obtain the intersection numbers among SUSY cycles which also agree with
geometrical expectation.

</DOC>
<DOC>
<DOCNO> 85644 </DOCNO>
String Theory in Electromagnetic Fields


  A review of various aspects of superstrings in background electromagnetic
fields is presented. Topics covered include the Born-Infeld action, spectrum of
open strings in background gauge fields, the Schwinger mechanism,
finite-temperature formalism and Hagedorn behaviour in external fields, Debye
screening, D-brane scattering, thermodynamics of D-branes, and noncommutative
field and string theories on D-branes. The electric field instabilities are
emphasized throughout and contrasted with the case of magnetic fields. A new
derivation of the velocity-dependent potential between moving D-branes is
presented, as is a new result for the velocity corrections to the one-loop
thermal effective potential.

</DOC>
<DOC>
<DOCNO> 151263 </DOCNO>
Quantum Field Theory from First Principles


  When quantum fields are studied on manifolds with boundary, the corresponding
one-loop quantum theory for bosonic gauge fields with linear covariant gauges
needs the assignment of suitable boundary conditions for elliptic differential
operators of Laplace type. There are however deep reasons to modify such a
scheme and allow for pseudo-differential boundary-value problems. When the
boundary operator is allowed to be pseudo-differential while remaining a
projector, the conditions on its kernel leading to strong ellipticity of the
boundary-value problem are studied in detail. This makes it possible to develop
a theory of one-loop quantum gravity from first principles only, i.e. the
physical principle of invariance under infinitesimal diffeomorphisms and the
mathematical requirement of a strongly elliptic theory. It therefore seems that
a non-local formulation of quantum field theory has some attractive features
which deserve further investigation.

</DOC>
<DOC>
<DOCNO> 85115 </DOCNO>
A relativistic calculation of super-Hubble suppression of inflation with


  We investigated the evolution of the primordial density perturbations
produced by inflation with thermal dissipation. A full relativistic analysis on
the evolution of initial perturbations from the warm inflation era to a
radiation-dominated universe has been developed. The emphasis is on tracking
the ratio between the adiabatic and the isocurvature mode of the initial
perturbations. This result is employed to calculate a testable factor: the
super-Hubble suppression of the power spectrum of the primordial perturbations.
We show that based on the warm inflation scenario, the super-Hubble suppression
factor, $s$, for an inflation with thermal dissipation is at least 0.5. This
prediction does not depend on the details of the model parameters. If $s$ is
larger than 0.5, it implies that the friction parameter $\Gamma$ is larger than
the Hubble expansion parameter $H$ during the inflation era.

</DOC>
<DOC>
<DOCNO> 84679 </DOCNO>
Gamma-ray bursts as the birth-cries of black holes


  The origin of cosmic gamma-ray bursts remains one of the most intriguing
puzzles in astronomy. We suggest that purely general relativistic effects in
the collapse of massive stars could account for these bursts. The late
formation of closed trapped surfaces can occur naturally, allowing the escape
of huge energy from curvature-generated fireballs, before these are hidden
within a black hole.

</DOC>
<DOC>
<DOCNO> 178592 </DOCNO>
Nuclear isotope thermometry


  We discuss different aspects which could influence temperatures deduced from
experimental isotopic yields in the multifragmentation process. It is shown
that fluctuations due to the finite size of the system and distortions due to
the decay of hot primary fragments conspire to blur the temperature
determination in multifragmentation reactions. These facts suggest that caloric
curves obtained through isotope thermometers, which were taken as evidence for
a first-order phase transition in nuclear matter, should be investigated very
carefully.

</DOC>
<DOC>
<DOCNO> 150680 </DOCNO>
Vanishing Next-to-Leading Corrections to the \beta-Function of the SUSY


  We study the ultraviolet properties of the supersymmetric CP^{N-1} sigma
model in three dimensions to next-to-leading order in the 1/N expansion. We
calculate the \beta-function to this order and verify that it has no
next-to-leading order corrections.

</DOC>
<DOC>
<DOCNO> 152510 </DOCNO>
Consistent gravitino couplings in non-supersymmetric strings


  The massless spectrum of the ten dimensional USp(32) type I string has an N=1
supergravity multiplet coupled to non-supersymmetric matter. This raises the
question of the consistency of the gravitino interactions. We resolve this
apparent puzzle by arguing for the existence of a local supersymmetry which is
non-linearly realised in the open sector. We determine the leading order low
energy effective Lagrangian. Similar results are expected to apply to lower
dimensional type I models where supergravity is coupled to non-supersymmetric
branes.

</DOC>
<DOC>
<DOCNO> 13910 </DOCNO>
Charge and spin separation in the 1D Hubbard model


  We consider the repulsive Hubbard model in one dimension and show the
different mechanisms present in the charge and spin separation phenomena for an
electron, at half filling and bellow half filling. We also comment recent
experimental results.

</DOC>
<DOC>
<DOCNO> 68901 </DOCNO>
Neutrino Oscillation and Charged Lepton-Flavor Violation in the


  The neutrino experiment results suggest that the neutrinos have finite masses
and the lepton-flavor symmetries are violating in nature. In the supersymmetric
models, the charged lepton-flavor violating processes, such as mu -> e gamma
and tau -> mu gamma, may have the branching ratios accessible to the future
experiments, depending on origins of the neutrino masses and the SUSY breaking.
In this paper we discuss the branching ratios in the supergravity scenario
using the current solar and atmospheric neutrino experimental data.

</DOC>
<DOC>
<DOCNO> 8838 </DOCNO>
Membrane boundary condition


  Using a microscopic phase-space model of the membrane system, the boundary
condition at a membrane is derived. According to the condition, the substance
flow across the membrane is proportional to the difference of the substance
concentrations at the opposite membrane surfaces. The Green's function of the
diffusion equation is found for the derived boundary condition and the exact
solution of the equation is given.

</DOC>
<DOC>
<DOCNO> 150821 </DOCNO>
T-duality Covariance of SuperD-branes


  T-duality realized on SuperD-brane effective actions probing in constant
$G_{mn}$ and $b_{mn}$ backgrounds is studied from a pure world volume point of
view. It is proved that requiring {\em T-duality covariance} of such actions
``fixes'' the T-duality transformations of the world volume dynamical fields,
and consequently, of the NS-NS and R-R coupling superfields. The analysis is
extended to uncover the mapping of the symmetry structure associated with these
SuperD-brane actions. In particular, we determine the T-duality transformation
properties of kappa symmetry and supersymmetry, which allow us to prove that
bosonic supersymmetric world volume solitons of the original theory generate,
through T-duality, the expected ones in the T-dual theory. The latter proof is
generalized to arbitrary bosonic backgrounds. We conclude with some comments on
extensions of our approach to arbitrary kappa symmetric backgrounds, non-BPS
D-branes and non-abelian SuperD-branes.

</DOC>
<DOC>
<DOCNO> 150911 </DOCNO>
D-branes and boundary states in closed string theories


  In this Ph.D. thesis, we study some aspects of strings and branes. We mainly
focus on anomalous D-brane couplings and on non-supersymmetric branes.
  In Chapter 2, we illustrate three key concepts in a field theory context:
duality, supersymmetry and anomaly inflow.
  Chapter 3 contains an introduction to string theory, emphasizing the concepts
relevant to this thesis, like string scattering amplitudes and D-brane actions.
  In Chapter 4, we introduce the boundary state formalism and use it to check
the presence of anomalous couplings in the D-brane Wess-Zumino action. In
addition, we show that this action also contains non-anomalous terms.
  Chapter 5 gives a BPS analysis of D-branes in D-brane backgrounds, focusing
on the baryon vertex in the AdS/CFT correspondence.
  Chapter 6 is devoted to branes in type 0 string theory. We derive the D-brane
Wess-Zumino action and the massless spectra of NS-fivebranes, and combine these
ingredients to comment on type 0B S-duality.
  In Chapter 7, we study non-BPS D-branes in type II string theory. We propose
a Wess-Zumino action for these branes, check it by computing string scattering
amplitudes and show that it is consistent with the interpretation of BPS
D-branes as topologically non-trivial tachyon configurations on a non-BPS
D-brane.

</DOC>
<DOC>
<DOCNO> 170406 </DOCNO>
Experimental demonstration of ground state laser cooling with


  Ground state laser cooling of a single trapped ion is achieved using a
technique which tailors the absorption profile for the cooling laser by
exploiting electromagnetically induced transparency in the Zeeman structure of
a dipole transition. This new method is robust, easy to implement and proves
particularly useful for cooling several motional degrees of freedom
simultaneously, which is of great practical importance for the implementation
of quantum logic schemes with trapped ions.

</DOC>
<DOC>
<DOCNO> 120052 </DOCNO>
Explosions During Galaxy Formation


  As an idealized model of the effects of energy release by supernovae during
galaxy formation, we consider an explosion at the center of a halo which forms
at the intersection of filaments in the plane of a cosmological pancake by
gravitational instability during pancake collapse. Such halos resemble the
virialized objects found in N-body simulations in a CDM universe and,
therefore, serve as a convenient, scale-free test-bed model for galaxy
formation. ASPH/P3M simulations reveal that such explosions are anisotropic.
The energy and metals are channeled into the low density regions, away from the
pancake plane. The pancake remains essentially undisturbed, even if the
explosion is strong enough to blow away all the gas located inside the halo at
the onset of the explosion and reheat the IGM surrounding the pancake. Infall
quickly replenishes this ejected gas and gradually restores the gas fraction as
the halo mass continues to grow. Estimates of the collapse epoch and SN
energy-release for galaxies of different mass in the CDM model can relate these
results to scale-dependent questions of blow-out and blow-away and their
implication for early IGM heating and metal enrichment and the creation of
dark-matter-dominated dwarf galaxies.

</DOC>
<DOC>
<DOCNO> 122964 </DOCNO>
Linking the Metallicity Distribution of Galactic Halo Stars to the


  We compare the metallicity distribution of Galactic Halo stars with 3D
realizations of hierarchical galaxy formation. Outflows from dwarf galaxies
enrich the intergalactic medium inhomogeneously, at a rate depending on the
local galaxy density. Consequently, the first stars created in small
early-forming galaxies are less metal-rich that the first stars formed in more
massive galaxies which typically form later. As most halo stars are likely to
originate in accreted dwarfs, while disk stars formed out of outflow-enriched
gas, this scenario naturally generates a ``metallicity floor'' for old disk
stars, which we find to be roughly coincident with the higher end of our
predicted metallicity distribution of halo stars, in agreement with
observations. The broad and centrally peaked distribution of halo star
metallicities is well reproduced in our models, with a natural dispersion
depending on the exact accretion history. Our modeling includes the important
``baryonic stripping'' effect of early outflows, which brush away the tenuously
held gas in neighboring pre-virialized density perturbations. This stripping
process does not significantly modify the predicted shape of the halo star
metal distribution but inhibits star-formation and hence the number of accreted
stars, helping to reproduce the observed total Galactic halo luminosity and
also the lack of low-luminosity local dwarf galaxies relative to N-body
predictions.

</DOC>
<DOC>
<DOCNO> 68999 </DOCNO>
Field-Dependent BRS Tranformations and Correct Prescription for


  The axial-gauge boson propagator contains 1/(n.k)^p-type singularities. These
singularities have generally been treated by inventing prescriptions for them.
We propose an alternative procedere for treating these singularities in the
path-integral formalism using the known way of treating the 1/k^{2n}-type
singularities in Lorentz-type gauges. For this purpose we use a finite
field-dependent BRS transformation that inerpolates between the Lorentz and
axial-type gauges. We arrive at the \epsilon-dependent tree propagator in
axial-type gauges.

</DOC>
<DOC>
<DOCNO> 11531 </DOCNO>
Spontaneous Magnetisation in a Quantum Wire


  An existence of predominant symmetrical spin configuration (spin polarised
phase) and "diluted" density of states (pseudo-gap) in a layer under the Fermi
level in a quantum wire is predicted. The condition of cross-over from
non-polarised phase to polarised one was derived. The transition occurs for
sufficiently low electron density in a wire and is accompanied by an acute
decrease of electron density of states near the Fermi level.It may result in a
corresponding decrease of conductance. A similar effect may exist in a
two-dimensional electron gas.

</DOC>
<DOC>
<DOCNO> 170560 </DOCNO>
Geometry and Product States


  As separable states are a convex combination of product states, the geometry
of the manifold of product states is studied. Prior results by Sanpera, Vidal
and Tarrach are extended. Furthermore, it is proven that states in the set
tangent to the manifold of product states, at the maximally mixed state are
separable; the set normal constains, among others, all maximally entangled
states. A canonical decomposition is given. A surprising result is that for the
case of two particles, the closest product state to the maximally entangled
state is the maximally mixed state. An algorithm is provided to find the
closest product state.

</DOC>
<DOC>
<DOCNO> 118728 </DOCNO>
Additional Information from Astrometric Gravitational Microlensing


  Astrometric observations of microlensing events were originally proposed to
determine the lens proper motion with which the physical parameters of lenses
can be better constrained. In this proceeding, we demonstrate that besides this
original usage astrometric microlensing observations can be additionally used
in obtaining various important information about lenses. First, we demonstrate
that the lens brightness can be determined with astrometric observations,
enabling one to know whether the event is caused by a bright star or a dark
lens. Second, we show that with additional information from astrometric
observations one can resolve the ambiguity of the photometric binary lens fit
and thus uniquely determine the binary lens parameters. Finally, we propose two
astrometric methods that can resolve the degeneracy in the photometric lens
parallax determination. Since one can measure both the proper motion and the
parallax by these methods, the lens parameters of individual events can be
uniquely determined.

</DOC>
<DOC>
<DOCNO> 84822 </DOCNO>
Green's functions for topology change


  We explicitly calculate Green's functions for quantum changes of topology in
Friedman-Lemaitre-Robertson-Walker Universes, whose spacelike sections are
compact but with distinct topologies depending on the curvature parameter $k$.
We use the long-wavelength approximation at second order, and we demonstrate
that quantum topological transitions from $k=-1$ to $k=1$ (and vice-versa) are
allowed whereas no transition to a flat section is possible establishing thus a
selection rule. Finally, a toy model is considered where all these properties
are investigated concretely.

</DOC>
<DOC>
<DOCNO> 118370 </DOCNO>
X-ray variability and prediction of TeV emission in the HBL 1ES1101-232


  1ES1101-232 is a bright BL Lac of the High frequency peak class. We present
here the results of two BeppoSAX observations in which the source has shown a
variation of about 30% in flux with a corresponding spectral variability. We
interpret the overall spectral energy distribution in terms of an homogeneous
SSC model and, by using also the TeV upper limit from a short Mark 6 pointing,
derive constraints on the physical parameters of the source, in particular on
the magnetic field strength. The overall Spectral Energy Distribution makes
1ES1101-232 a very promising candidate for TeV detection.

</DOC>
<DOC>
<DOCNO> 151747 </DOCNO>
On the DLCQ as a light-like limit in string theory


  We study the issue of defining the discrete light-cone quantization (DLCQ) in
perturbative string theory as a light-like limit. While this limit is
unproblematic at the classical level, it is non-trivial at the quantum level
due to the divergences by the zero-mode loops. We reconsider this problem in
bosonic string theory. We construct the multi-loop scattering amplitudes in
both open and closed string theories by using the method of Kikkawa, Sakita and
Virasoro (KSV), and then we show that these scattering amplitudes are perfectly
well-defined in this limit. We also discuss the vacuum amplitudes of the string
theory. They are, however, ill-defined in the light-like limit due to the
zero-mode loop divergences, and hence we want supersymmetry to cure those
pathological divergences even in string theory.

</DOC>
<DOC>
<DOCNO> 118428 </DOCNO>
Model of peak separation in the gamma lightcurve of the Vela pulsar


  The separation $\del$ between two peaks in the gamma-ray pulse profile is
calculated as a function of energy for several polar cap models with
curvature-radiation-induced cascades. The Monte Carlo results are interpreted
with the help of analytical approximations and discussed in view of the recent
data analysis for the Vela pulsar (Kanbach 1999). We find that the behaviour of
$\del$ as a function of photon energy $\epsilon$ depends primarily on local
values of the magnetic field, $B_{\rm local}$, in the region where
electromagnetic cascades develop. For low values of $B_{\rm local}$ ($<
10^{12}$ G), $\del(\epsilon)$ is kept constant. However, for stronger magnetic
fields ($\ga 10^{12}$ G) in the hollow-column model $\del$ decreases with
increasing photon energy at a rate dependent on maximum energy of beam
particles as well as on viewing geometry. There exists a critical photon energy
$\et$ above which the relation $\del(\epsilon)$ changes drastically: for
$\epsilon > \et$, in hollow-column models the separation $\del$ increases
(whereas in filled-column model it decreases) rapidly with increasing
$\epsilon$, at a rate of $\sim 0.28$ of the total phase per decade of photon
energy. The existence of critical energy $\et$ is a direct consequence of
one-photon magnetic absorption effects. In general, $\et$ is located close to
the high-energy cutoff of the spectrum, thus photon statistics at $\et$ should
be very low. That will make difficult to verify the existence of $\et$ in real
gamma-ray pulsars. Spectral properties of the Vela pulsar would favour those
models which use low values of magnetic field in the emission region ($B_{\rm
local} \simless 10^{11}$ G) which in turn implies a constant value of the
predicted $\del$ within EGRET range.

</DOC>
<DOC>
<DOCNO> 14104 </DOCNO>
Watching dark solitons decay into vortex rings in a Bose-Einstein


  We have created spatial dark solitons in two-component Bose-Einstein
condensates in which the soliton exists in one of the condensate components and
the soliton nodal plane is filled with the second component. The filled
solitons are stable for hundreds of milliseconds. The filling can be
selectively removed, making the soliton more susceptible to dynamical
instabilities. For a condensate in a spherically symmetric potential, these
instabilities cause the dark soliton to decay into stable vortex rings. We have
imaged the resulting vortex rings.

</DOC>
<DOC>
<DOCNO> 68570 </DOCNO>
The Interface of Cosmology with String and M(ILLENNIUM) Theory


  The purpose of this review is to discuss recent developments occurring at the
interface of cosmology with string and M-theory. We begin with a short review
of 1980s string cosmology and the Brandenberger-Vafa mechanism for explaining
spacetime dimensionality. It is shown how this scenario has been modified to
include the effects of p-brane gases in the early universe. We then introduce
the Pre-Big-Bang scenario (PBB), Ho\v{r}ava-Witten heterotic M-theory and the
work of Lukas, Ovrut and Waldram, and end with a discussion of large extra
dimensions, the Randall-Sundrum model and Brane World cosmologies.

</DOC>
<DOC>
<DOCNO> 116291 </DOCNO>
Photo-induced intermolecular charge transfer in porphyrin complexes


  Optical excitation of the sequential supermolecule H_2P-ZnP-Q induces an
electron transfer from the free-base porphyrin (H_2P) to the quinone (Q) via
the zinc porphyrin (ZnP). This process is modeled by equations of motion for
the reduced density matrix which are solved numerically and approximately
analytically. These two solutions agree very well in a great region of
parameter space. It is shown that for the majority of solvents the electron
transfer occurs with the superexchange mechanism.

</DOC>
<DOC>
<DOCNO> 8337 </DOCNO>
Evidence for a two component magnetic response in UPt3


  The magnetic response of the heavy fermion superconductor UPt_3 has been
investigated on a microscopic scale by muon Knight shift studies. Two distinct
and isotropic Knight shifts have been found for the field in the basal plane.
While the volume fractions associated with the two Knight shifts are
approximately equal at low and high temperatures, they show a dramatic and
opposite temperature dependence around T_N. Our results are independent on the
precise muon localization site. We conclude that UPt_3 is characterized by a
two component magnetic response.

</DOC>
<DOC>
<DOCNO> 80884 </DOCNO>
Charmonium in finite temperature lattice QCD


  We study hadron properties near the deconfining transition in the finite
temperature lattice QCD. This paper focus on the heavy quarkonium states, such
as $J/\psi$ meson. We compare the meson correlators above and below $T_c$ and
discuss the possibility of the $c\bar{c}$ bound state by observing the wave
function.

</DOC>
<DOC>
<DOCNO> 170634 </DOCNO>
Effect of symmetry breaking on level curvature distributions


  We derive an exact general formalism that expresses the eigenvector and the
eigenvalue dynamics as a set of coupled equations of motion in terms of the
matrix elements dynamics. Combined with an appropriate model Hamiltonian, these
equations are used to investigate the effect of the presence of a discrete
symmetry in the level curvature distribution. An explanation of the unexpected
behavior of the data regarding frequencies of acoustic vibrations of quartz
block is provided.

</DOC>
<DOC>
<DOCNO> 8808 </DOCNO>
Evidence of quantum criticality in the doped Haldane system Y2BaNiO5


  Experimental bulk susceptibility X(T) and magnetization M(H,T) of the
S=1-Haldane chain system doped with nonmagnetic impurities, Y2BaNi1-xZnxO5
(x=0.04,0.06,0.08), are analyzed. A numerical calculation for the low-energy
spectrum of non-interacting open segments describes very well experimental data
above 4 K. Below 4 K, we observe power-law behaviors, X(T)=T^-alpha and
M(H,T)/T^(1-alpha)=f(alpha,(H/T)), with alpha (<1) depending on the doping
concentration x.This observation suggests the appearance of a gapless quantum
phase due to a broad distribution of effective couplings between the
dilution-induced moments.

</DOC>
<DOC>
<DOCNO> 69984 </DOCNO>
K_{L,S} \to \pi \pi \nu \bar{\nu} Decays Within and Beyond the Standard


  The decays K_{L,S} -> \pi^o \pi^o \nu \bar{\nu} and K_{L,S} -> \pi^+ \pi^-
\nu \bar{\nu} involve the weak transition from a strange to a non-strange
quark. Although they have considerably smaller branching ratios than those for
the corresponding rare processes involving single pions, some may be more
distinguishable experimentally from background processes and thus could provide
another probe of the s -> d \nu \bar{\nu} transition. Using recent knowledge of
the CKM matrix elements and measurements of related processes, we give improved
predictions for their branching ratios both within and beyond the Standard
Model.

</DOC>
<DOC>
<DOCNO> 101916 </DOCNO>
Harmonic analysis on the SU(2) dynamical quantum group


  Dynamical quantum groups were recently introduced by Etingof and Varchenko as
an algebraic framework for studying the dynamical Yang-Baxter equation, which
is precisely the Yang-Baxter equation satisfied by 6j-symbols. We investigate
one of the simplest examples, generalizing the standard SU(2) quantum group.
The matrix elements for its corepresentations are identified with Askey-Wilson
polynomials, and the Haar measure with the Askey-Wilson measure. The discrete
orthogonality of the matrix elements yield the orthogonality of q-Racah
polynomials (or quantum 6j-symbols). The Clebsch-Gordan coefficients for
representations and corepresentations are also identified with q-Racah
polynomials. This results in new algebraic proofs of the Biedenharn-Elliott
identity satisfied by quantum 6j-symbols.

</DOC>
<DOC>
<DOCNO> 7827 </DOCNO>
Presence of Many Stable Nonhomogeneous States in an Inertial


  A new single lane car following model of traffic flow is presented. The model
is inertial and free of collisions. It demonstrates experimentally observed
features of traffic flow such as the existence of three regimes: free,
fluctuative (synchronized) and congested (jammed) flow; bistability of free and
fluctuative states in a certain range of densities, which causes the hysteresis
in transitions between these states; jumps in the density-flux plane in the
fluctuative regime and gradual spatial transition from synchronized to free
flow. Our model suggests that in the fluctuative regime there exist many stable
states with different wavelengths, and that the velocity fluctuations in the
congested flow regime decay approximately according to a power law in time.

</DOC>
<DOC>
<DOCNO> 122218 </DOCNO>
The Progenitor Masses of Wolf-Rayet Stars and Luminous Blue Variables


  Here we examine 12 Galactic clusters and OB associations containing
Wolf-Rayet stars (W-Rs) and/or Luminous Blue Variables (LBVs), in order to
assess the progentor masses of these evolved massive stars. We find that in the
Milky Way, early-type WN stars evolve from stars with masses as low as 20Mo.
Some early-type WN stars are found in clusters with very high turn-off masses,
supporting our earlier results that the "WNE" class of W-Rs is a common stage
in the evolution of stars with a wide range of mases. In contrast, the
late-type WNs (particularly those of WN7 class) and the LBVs are only found in
clusters with the very highest turn-off masses, suggesting that only the most
massive stars evolve to these objects. An examination of the environment of the
archetype LBV Eta Car reveals that this star is coeval with the rest of the
Tr14/16 association, suggesting that its LBV properties is a normal consequence
of evolution, and has little to do with the possibility that it is a binary.

</DOC>
<DOC>
<DOCNO> 8754 </DOCNO>
A Fresh Look at Entropy and the Second Law of Thermodynamics


  This paper is a non-technical, informal presentation of our theory of the
second law of thermodynamics as a law that is independent of statistical
mechanics and that is derivable solely from certain simple assumptions about
adiabatic processes for macroscopic systems. It is not necessary to assume
a-priori concepts such as "heat", "hot and cold", "temperature". These are
derivable from entropy, whose existence we derive from the basic assumptions.
See cond-mat/9708200 and math-ph/9805005.

</DOC>
<DOC>
<DOCNO> 101511 </DOCNO>
Computing and Sampling Restricted Vertex Degree Subgraphs and


  Let $G=(V,E)$ be a bipartite graph embedded in a plane (or $n$-holed torus).
Two subgraphs of $G$ differ by a {\it $Z$-transformation} if their symmetric
difference consists of the boundary edges of a single face---and if each
subgraph contains an alternating set of the edges of that face. For a given
$\phi: V \mapsto \mathbb Z^+$, $S_{\phi}$ is the set of subgraphs of $G$ in
which each $v\in V$ has degree $\phi(v)$. Two elements of $S_{\phi}$ are said
to be adjacent if they differ by a $Z$-transformation. We determine the
connected components of $S_{\phi}$ and assign a {\it height function} to each
of its elements.
  If $\phi$ is identically two, and $G$ is a grid graph, $S_{\phi}$ contains
the partitions of the vertices of $G$ into cycles. We prove that we can always
apply a series of $Z$-transformations to decrease the total number of cycles
provided there is enough ``slack'' in the corresponding height function. This
allows us to determine in polynomial time the minimal number of cycles into
which $G$ can be partitioned provided $G$ has a limited number of non-square
faces. In particular, we determine the Hamiltonicity of polyomino graphs in
$O(|V|^2)$ steps. The algorithm extends to $n$-holed-torus-embedded graphs that
have grid-like properties. We also provide Markov chains for sampling and
approximately counting the Hamiltonian cycles of $G$.

</DOC>
<DOC>
<DOCNO> 121329 </DOCNO>
Parsec-scale properties of a complete sample of radio galaxies


  We report the most important results on the parsec-scale properties of a
complete sample of radio galaxies carried out at radio frequencies with the
Global VLBI array and with the VLBA. Relativistic parsec-scale jets are common
both in FRI and FRII radio galaxies, and their orientation to the line of sight
is in agreement with the expectations from the unified schemes for radio loud
AGNs. Proper motion has been detected in a few FRI galaxies in the sample. FRI
and FRII radio galaxies exhibit very similar properties on the parsec-scale.
Finally a few radio sources in the sample show evidence of velocity structure
in the parsec-scale jet, i.e. a central spine with high Lorentz factor $\gamma$
and slower layers.

</DOC>
<DOC>
<DOCNO> 71746 </DOCNO>
Flavor Alignment in SUSY GUTs


  A Supersymmetric Grand unified model is constructed based on SO(10)xSO(10)
symmetry in which new types of Yukawa matrices couple standard and exotic
fermions. Evolution of these couplings from the Grand Unified scale to the
electroweak scale causes some of them to be driven to their fixed points. This
solves the supersymmetric alignment problem and ensures that there are no
observable flavor changing neutral currents mediated by supersymmetric
particles. Fermion hierarchy and neutrino mixing constraints are automatically
satisfied in this formalism.

</DOC>
<DOC>
<DOCNO> 100400 </DOCNO>
A Note on Cyclic Gradients


  Simple necessary and sufficient conditions for a $n$-tuple of noncommutative
polynomials to be a cyclic gradient are given and similarly for a
noncommutative polynomial to have a vanishing cyclic gradient. Connections with
free probability are explained.

</DOC>
<DOC>
<DOCNO> 116983 </DOCNO>
Ground Motion Studies and Modeling for the Interaction Region of a


  Ground motion may be a limiting factor in the performance of future linear
colliders. Cultural noise sources, an important component of ground motion, are
discussed here, with data from the SLD region at SLAC.

</DOC>
<DOC>
<DOCNO> 119016 </DOCNO>
Windows through the Dusty Disks Surrounding the Youngest Low Mass


  The formation and evolution of young low mass stars are characterized by
important processes of mass loss and accretion ocurring in the innermost
regions of their placentary circumstellar disks. Because of the large
obscuration of these disks at optical and infrared wavelengths in the early
protostellar stages (Class 0 Sources), they were previously detected only at
radio wavelengths using interferometric techniques. We have detected with the
Infrared Space Observatory (ISO) the mid-infrared emission associated with the
Class 0 protostar VLA1 in the HH1-2 region located in the Orion nebula. The
emission arises in the three wavelength windows at 5.3, 6.6 and 7.5 micras
where the absorption due to ices and silicates has a local minimum that exposes
the central parts of the youngest protostellar systems to mid-infrared
investigations. The mid-infrared emission arises from a central source with 4
AU diameter at an averaged temperature of 700 K, deeply embedded in a dense
region with a visual extinction of Av=80-100mag.

</DOC>
<DOC>
<DOCNO> 117132 </DOCNO>
On Optimality in Auditory Information Processing


  We study limits for the detection and estimation of weak sinusoidal signals
in the primary part of the mammalian auditory system using a stochastic
Fitzhugh-Nagumo (FHN) model and an action-reaction model for synaptic
plasticity. Our overall model covers the chain from a hair cell to a point just
after the synaptic connection with a cell in the cochlear nucleus. The
information processing performance of the system is evaluated using so called
phi-divergences from statistics which quantify a dissimilarity between
probability measures and are intimately related to a number of fundamental
limits in statistics and information theory (IT). We show that there exists a
set of parameters that can optimize several important phi-divergences
simultaneously and that this set corresponds to a constant quiescent firing
rate (QFR) of the spiral ganglion neuron. The optimal value of the QFR is
frequency dependent but is essentially independent of the amplitude of the
signal (for small amplitudes). Consequently, optimal processing according to
several standard IT criteria can be accomplished for this model if and only if
the parameters are ``tuned'' to values that correspond to one and the same QFR.
This offers a new explanation for the QFR and can provide new insight into the
role played by several other parameters of the peripheral auditory system.

</DOC>
<DOC>
<DOCNO> 13229 </DOCNO>
Mean Field theory for a driven granular gas of frictional particles


  We propose a mean field (MF) theory for a homogeneously driven granular gas
of inelastic particles with Coulomb friction. The model contains three
parameters, a normal restitution coefficient $r_n$, a maximum tangential
restitution coefficient $r_t^m$, and a Coulomb friction coefficient $\mu$. The
parameters can be tuned to explore a wide range of physical situations. In
particular, the model contains the frequently used $\mu \to \infty$ limit as a
special case. The MF theory is compared with the numerical simulations of a
randomly driven monolayer of spheres for a wide range of parameter values. If
the system is far away from the clustering instability ($r_n \approx 1$), we
obtain a good agreement between mean field and simulations for $\mu=0.5$ and
$r_t^m=0.4$, but for much smaller values of $r_n$ the agreement is less good.
We discuss the reasons of this discrepancy and possible refinements of our
computational scheme.

</DOC>
<DOC>
<DOCNO> 67748 </DOCNO>
Gluon Radiation in Top Production and Decay


  We present the results of an exact calculation of gluon radiation in top
production and decay at high energy electron-positron colliders. We include all
spin correlations and interferences, the bottom quark mass, and finite top
width effects in the matrix element calculation. We study properties of the
radiated gluons and implications for top mass measurement.

</DOC>
<DOC>
<DOCNO> 13753 </DOCNO>
A New Criterion for Crack Formation in Disordered Materials


  Crack formation is conventionally described as a nucleation phenomenon
despite the fact that the temperatures necessary to overcome the nucleation
barrier are far too high. In this paper we consider the possibility that cracks
are created due to the presence of frozen disorder (e.g. heterogeneities or
frozen dislocations). In particular we calculate the probability for the
occurrence of a critical crack in a quasi two-dimensional disordered elastic
system. It turns out that this probability takes the form of an Arrhenius law
(as for thermal nucleation) but with the temperature T replaced by an effective
disorder temperature T_eff which depends on the strength of the disorder. The
extension of these results to d=3 dimensions is briefly discussed.

</DOC>
<DOC>
<DOCNO> 100859 </DOCNO>
Bijective and general arithmetic codings for Pisot automorphisms of the


  Let $T$ be an algebraic automorphism of $\mathbb{T}^{m}$ having the following
property: the characteristic polynomial of its matrix is irreducible over
$\mathbb{Q}$, and a Pisot number $\beta$ is one of its roots. We define the
mapping $\phi_{\mathbf{t}}$ acting from the two-sided $\beta$-compactum onto
$\mathbb{T}^{m}$ as follows: \[ \phi_{\mathbf{t}}(\bar{\epsilon})=
\sum_{k\in\mathbb{Z}}\epsilon_{k}T^{-k}\mathbf{t}, \] where $\mathbf{t}$ is a
fundamental homoclinic point for $T$, i.e., a point homoclinic to $\mathbf{0}$
such that the linear span of its orbit is the whole homoclinic group (provided
such a point exists). We call such a mapping an arithmetic coding of $T$. This
paper is aimed to show that under some natural hypothesis on $\beta$ (which is
apparently satisfied for all Pisot units) the mapping $\phi_{\mathbf{t}}$ is
bijective a.e. with respect to the Haar measure on the torus. Besides, we study
the case of more general parameters $\mathbf{t}$, not necessarily fundamental,
and relate the number of preimages of $\phi_{\mathbf{t}}$ to certain
number-theoretic quantities. We also give several full criteria for $T$ to
admit a bijective arithmetic coding. This work continues the study begun in
[Sidorov & Vershik, Journal Dynam. Control Systems 4 (1998), 365-399] for the
special case $m=2$.

</DOC>
<DOC>
<DOCNO> 69645 </DOCNO>
Self-Breaking of the Standard Model Gauge Symmetry


  If the gauge fields of the Standard Model propagate in TeV-size extra
dimensions, they rapidly become strongly coupled and can form scalar bound
states of quarks and leptons. If the quarks and leptons of the third generation
propagate in 6 or 8 dimensions, we argue that the most tightly bound scalar is
a composite of top quarks, having the quantum numbers of the Higgs doublet and
a large coupling to the top quark. In the case where the gauge bosons propagate
in a bulk of a certain volume, this composite Higgs doublet can successfully
trigger electroweak symmetry breaking. The mass of the top quark is correctly
predicted to within 20%, without the need to add a fundamental Yukawa
interaction, and the Higgs boson mass is predicted to lie in the range 165 -
230 GeV. In addition to the Higgs boson, there may be a few other scalar
composites sufficiently light to be observed at upcoming collider experiments.

</DOC>
<DOC>
<DOCNO> 100001 </DOCNO>
Study on the family of K3 surfaces induced from the lattice $(D_4)^3


  Let us consider the rank 14 lattice $P=D_4^3\oplus < -2> \oplus < 2>$. We
define a K3 surface S of type P with the property that $P\subset {\rm Pic}(S)
$, where ${\rm Pic}(S) $ indicates the Picard lattice of S. In this article we
study the family of K3 surfaces of type P with a certain fixed
multipolarization. We note the orthogonal complement of P in the K3 lattice
takes the form $$ U(2)\oplus U(2)\oplus (-2I_4). $$ We show the following
results: \item{(1)}
  A K3 surface of type P has a representation as a double cover over ${\bf
P}^1\times {\bf P}^1$ as the following affine form in (s,t,w) space: $$ S=S(x):
w^2=\prod_{k=1}^4 (x_{1}^{(k)}st+x_{2}^{(k)}s+x_{3}^{(k)}t+x_{4}^{(k)}), \
x_k=\pmatrix{x_{1}^{(k)}&x_{2}^{(k)}\cr x_{3}^{(k)}&x_{4}^{(k)}} \in M(2,{\bf
C}). $$ We make explicit description of the Picard lattice and the
transcendental lattice of S(x). \item{(2)}
  We describe the period domain for our family of marked K3 surfaces and
determine the modular group. \par \noindent \item{(3)}
  We describe the differential equation for the period integral of S(x) as a
function of $x\in (GL(2,{\bf C}))^4$. That bocomes to be a certain kind of
hypergeometric one. We determine the rank, the singular locus and the monodromy
group for it. \par \noindent \item{(4)} It appears a family of 8 dimensional
abelian varieties as the family of Kuga-Satake varieties for our K3 surfaces.
The abelian variety is characterized by the property that the endomorphism
algebra contains the Hamilton quarternion field over ${\bf Q}$.

</DOC>
<DOC>
<DOCNO> 101103 </DOCNO>
Antinomies of Mathematical Reason: The Inconsistency of Arithmetic and


  We elucidate an error in Goedel's own proof of Goedel's Theorems, and then
give a proof of the inconsistency of PM arithmetic, classical set theory and
related systems. The inconsistency proof proceeds by application of the first
axiom of propositional calculus to theorems arising from Kleene's (otherwise
correct) 1936 proof of a PM-isomorphic system's undecidability, showing that
theorems of the form R and ~R follow from it.

</DOC>
<DOC>
<DOCNO> 71739 </DOCNO>
Chiral Perturbation Theory and Unitarization


  We review our recent work on unitarization and chiral perturbation theory
both in the $\pi\pi$ and the $\pi N$ sectors. We pay particular attention to
the Bethe-Salpeter and Inverse Amplitude unitarization methods and their recent
applications to $\pi\pi$ and $\pi N$ scattering.

</DOC>
<DOC>
<DOCNO> 152142 </DOCNO>
Symmetries of string, M and F-theories


  The d=10 type II string theories, d=11 M-theory and d=12 F-theory have the
same symmetry group. It can be viewed either as a subgroup of a conformal group
OSp(1|64) or as a contraction of OSp(1|32). The theories are related by
different identifications of their symmetry operators as generators of
OSp(1|32). T- and S-dualities are recognized as redefinitions of generators.
Some (s,t) signatures of spacetime allow reality conditions on the generators.
All those that allow a real structure are related again by redefinitions within
the algebra, due to the fact that the algebra OSp(1|32) has only one real
realization. The redefinitions include space/space, time/time and space/time
dualities. A further distinction between the theories is made by the
identification of the translation generator. This distinguishes various
versions of type II string theories, in particular the so-called *-theories,
characterized by the fact that the P_0 generator is not the (unique)
positive-definite energy operator in the algebra.

</DOC>
<DOC>
<DOCNO> 40652 </DOCNO>
Multianode Photo Multipliers for Ring Imaging Cherenkov Detectors


  The 64-channel Multianode Photo Multiplier has been evaluated as a possible
choice for the photo detectors of the LHCb Ring Imaging Cherenkov detector.

</DOC>
<DOC>
<DOCNO> 84100 </DOCNO>
Physical Consequences of Moving Faster than Light in Empty Space


  Physical phenomena caused by particle's moving faster than light in a space
with multifractal time with dimension close to integer
($d_{t}=1+\epsilon(r(t),t), |\epsilon| \ll 1$ - time is almost homogeneous and
almost isotropic) are considered. The presence of gravitational field is taken
into account. According to the results of the developed by the author theory, a
particle with the rest energy $E_{0}$ would achieve the velocity of light if
given the energy of about $E \sim 10^{3}E_{0}$

</DOC>
<DOC>
<DOCNO> 80794 </DOCNO>
Center Vortices and Monopoles without lattice Gribov copies


  We construct a smooth gauge for the adjoint field which is free of
ambiguities on the lattice. In this Laplacian Center Gauge, center vortices and
monopoles appear together as local gauge defects. A numerical study of center
vortices in SU(2) and SU(3) supports equality of the $Z_N$ and SU(N) string
tensions in the continuum limit, and only then.

</DOC>
<DOC>
<DOCNO> 178655 </DOCNO>
On a q-analogue of the spin-orbit coupling


  Based on the tensor method, a q-analoque of the spin-orbit coupling is
introduced in a q-deformed Schroedinger equation, previously derived for a
central potential. Analytic expressions for the matrix elemnets of the
representation j=l\pm 1/2 are derived. The spectra of the harmonic oscillator
and the Coulomb potential are calculated numerically as a function of the
deformation parameter, without and with the spin-orbit coupling. The harmonic
oscillator spectrum presents strong analogies with the bound spectrum of an
Woods-Saxon potential customarily used in nuclear physics. The Coulomb spectrum
simulates relativistic effects. The addition of the spin-orbit coupling
reinforces this picture.

</DOC>
<DOC>
<DOCNO> 85119 </DOCNO>
Time-Symmetric ADI and Causal Reconnection: Stable Numerical Techniques


  Moving grids are of interest in the numerical solution of hydrodynamical
problems and in numerical relativity. We show that conventional integration
methods for the simple wave equation in one and more than one dimension exhibit
a number of instabilities on moving grids. We introduce two techniques, which
we call causal reconnection and time-symmetric ADI, which together allow
integration of the wave equation with absolute local stability in any number of
dimensions on grids that may move very much faster than the wave speed and that
can even accelerate. These methods allow very long time-steps, are fully
second-order accurate, and offer the computational efficiency of
operator-splitting.

</DOC>
<DOC>
<DOCNO> 84095 </DOCNO>
Spacetime perspective of Schwarzschild lensing


  We propose a definition of an exact lens equation without reference to a
background spacetime, and construct the exact lens equation explicitly in the
case of Schwarzschild spacetime. For the Schwarzschild case, we give exact
expressions for the angular-diameter distance to the sources as well as for the
magnification factor and time of arrival of the images. We compare the exact
lens equation with the standard lens equation, derived under the
thin-lens-weak-field assumption (where the light rays are geodesics of the
background with sharp bending in the lens plane, and the gravitational field is
weak), and verify the fact that the standard weak-field thin-lens equation is
inadequate at small impact parameter. We show that the second-order correction
to the weak-field thin-lens equation is inaccurate as well. Finally, we compare
the exact lens equation with the recently proposed strong-field thin-lens
equation, obtained under the assumption of straight paths but without the small
angle approximation, i.e., with allowed large bending angles. We show that the
strong-field thin-lens equation is remarkably accurate, even for lightrays that
take several turns around the lens before reaching the observer.

</DOC>
<DOC>
<DOCNO> 11668 </DOCNO>
Theory of extraordinary optical transmission through subwavelength hole


  We present a fully three-dimensional theoretical study of the extraordinary
transmission of light through subwavelength hole arrays in optically thick
metal films. Good agreement is obtained with experimental data. An analytical
minimal model is also developed, which conclusively shows that the enhancement
of transmission is due to tunneling through surface plasmons formed on each
metal-dielectric interfaces. Different regimes of tunneling (resonant through a
''surface plasmon molecule", or sequential through two isolated surface
plasmons) are found depending on the geometrical parameters defining the
system.

</DOC>
<DOC>
<DOCNO> 12208 </DOCNO>
Metal-insulator and magnetic collapse transitions in FeO at high


  The accuracy of LDA + U total energies is tested by predicting the high
pressure behavior of rocksalt-structured FeO, including metal-insulator and
magnetic transitions, equation of state, and lattice strain, as functions of
the Coulomb repulsion U. For U = 4.6 eV, 6.0 eV and 8.0 eV, two self-consistent
solutions, one with rhombohedral and one with monoclinic electronic symmetry,
are found, and for U = 4.6 eV the monoclinic solution becomes more stable than
the rhombohedral solution at 100 GPa, leading to an insulator-metal transition.
With increasing U, metallization occurs at higher pressures. Despite the
insulator-metal transition, the high-spin magnetic state persists to pressures
greater than 300 GPa for U > 0. The LDA + U method also gives improved
agreement with experiments for ground state properties as compared to LDA and
GGA methods.

</DOC>
<DOC>
<DOCNO> 71299 </DOCNO>
Soft Pomeron in QCD


  This is a talk, given at Diffraction'2000, Sept. 2 - 7, Centraro, Italy. This
talk is a brief presentation of our view on the Pomeron, as a non-perturbative
QCD phenomenon but from sufficiently short distances. Our approach is based on
the scale anomaly of QCD and emphasizes the r{\^o}le of semi-classical QCD
vacuum fields. We show that both the intercept and the slope of Pomeron
trajectory appear to be determined by the energy density of non-perturbative
QCD vacuum. The particular example of semi-classical QCD vacuum fields is
discussed based on a new type of instanton-induced interactions (``instanton
ladder'') that leads to the rising with energy cross section $\sigma \sim
s^{\Delta_P}$ of Regge type (the Pomeron).

</DOC>
<DOC>
<DOCNO> 119232 </DOCNO>
Discovery of 1RXS J171824.2-402934 as an X-ray burster


  We report the first-time detection of a type-I X-ray burst from a position
that is consistent with that of 1RXS J171824.2-402934. The detection was made
on Sep 23, 1996, with the Wide Field Cameras on board the BeppoSAX satellite.
The burst had a peak intensity of 1.3 Crab units in 2 to 28 keV and is
relatively long (at least 3.5 min). Analysis of the burst gives clear evidence
for photospheric radius expansion. Assuming the peak luminosity to be close to
the Eddington limit, standard burst parameters and taking into account
gravitational redshift effects, the distance to the source is approximately 6.5
kpc. No other bursts from this source have been observed during the rest of the
WFC observations. The detection of a type-I burst implies that 1RXS
J171824.2-402934in all likelihood is a low-mass X-ray binary where the compact
object is a neutron star.

</DOC>
<DOC>
<DOCNO> 9578 </DOCNO>
Bose-Einstein condensation in a stiff TOP trap with adjustable geometry


  We report on the realisation of a stiff magnetic trap with independently
adjustable trap frequencies, $\omega_z$ and $\omega_r$, in the axial and radial
directions respectively. This has been achieved by applying an axial modulation
to a Time-averaged Orbiting Potential (TOP) trap. The frequency ratio of the
trap, $\omega_z / \omega_r$, can be decreased continuously from the original
TOP trap value of 2.83 down to 1.6. We have transferred a Bose-Einstein
condensate (BEC) into this trap and obtained very good agreement between its
observed anisotropic expansion and the hydrodynamic predictions. Our method can
be extended to obtain a spherical trapping potential, which has a geometry of
particular theoretical interest.

</DOC>
<DOC>
<DOCNO> 68400 </DOCNO>
Scalar Exchange Forces and Generalized Most Attractive Channel Rule


  We discuss the possibility that fermionic condensates arise from the
dominance of scalar exchange forces over vector gluon exchange. When a scalar
in the adjoint representation is exchanged in the reaction $A+A \to A+A$, the
usual most attractive channel (MAC) rule is reversed in sign, with the
consequence that the formation of a condensate with the largest possible
Casimir is favored. More generally, when a scalar in a general representation
is exchanged in the reaction $A+B \to B+A$, the group theoretic sum giving the
force sign and strength can be expressed in terms of a Racah coefficient for
the group in question. We illustrate the formalism in the case of the group
SU(2), and give possible applications to SO(10) and $E_6$ grand unification.

</DOC>
<DOC>
<DOCNO> 9638 </DOCNO>
Gauge factor of thick film resistors: outcomes of the variable range


  Despite a large amount of data and numerous theoretical proposals, the
microscopic mechanism of transport in thick film resistors remains unclear.
However, recent low temperature measurements point toward a possible variable
range hopping mechanism of transport. Here we examine how such a mechanism
affects the gauge factor of thick film resistors. We find that at sufficiently
low temperatures $T$, for which the resistivity follows the Mott's law
$R(T)\sim \exp(T_0/T)^{1/4}$, the gauge factor GF is proportional to
$(T_0/T)^{1/4}$. Moreover, the inclusion of Coulomb gap effects leads to ${\rm
GF}\sim (T_0'/T)^{1/2}$ at lower temperatures. In addition, we study a simple
model which generalizes the variable range hopping mechanism by taking into
account the finite mean inter-grain spacing. Our results suggest a possible
experimental verification of the validity of the variable range hopping in
thick film resistors.

</DOC>
<DOC>
<DOCNO> 71019 </DOCNO>
Lepton asymmetries from neutrino oscillations


  Reasonably large relic neutrino asymmetries can be generated by
active-sterile neutrino oscillations. After briefly discussing possible
applications, I describe the Quantum Kinetic Equation formalism used to compute
the asymmetry growth curves. I then show how the basic features of these curves
can be understood on the basis of the adiabatic limit approximation in the
collision dominated epoch, and the pure MSW effect at lower temperatures.

</DOC>
<DOC>
<DOCNO> 170675 </DOCNO>
Tunable whispering gallery modes for spectroscopy and CQED experiments


  We have tuned the whispering gallery modes of a fused silica micro- resonator
over nearly 1 nm at 800 nm, i.e.over half of a free spectral range or the
equivalent of 10^6 linewidths of the resonator.This has been achieved by a new
method based on the stretching of a two-stem microsphere.The devices described
below will permit new Cavity-QED experiments with this ultra high .nesse
optical resonator when it is desirable to optimise its coupling to emitters
with given transition frequencies. The tuning capability demonstrated is
compatible with both UHV and low temperature operation which should be useful
for future experiments with laser cooled atoms or single quantum dots.A general
overview of the current state of the art in microspheres is given as well as a
more general introduction.

</DOC>
<DOC>
<DOCNO> 169795 </DOCNO>
Reply to a review of photon-exchange interactions by Opatrny and Kurizki


  In a recent review article, Opatrny and Kurizki [submitted to Fortschr.
Phys., e-print quant-ph/0003010] discussed a number of issues related to the
feasibility of quantum computation based on photon-exchange interactions. This
Reply summarizes my view of each of the issues and the overall prospects for
quantum computing based on photon-exchange interactions.

</DOC>
<DOC>
<DOCNO> 11980 </DOCNO>
Phonons in intrinsic Josephson systems with parallel magnetic field


  Subgap resonances in the I-V curves of layered superconductors are explained
by the coupling between Josephson oscillations and phonons with dispersion in
c-direction. In the presence of a magnetic field applied parallel to the layers
additional structures due to fluxon motion appear. Their coupling with phonons
is investigated theoretically and a shift of the phonon resonances in strong
magnetic fields is predicted.

</DOC>
<DOC>
<DOCNO> 40168 </DOCNO>
Measurement of the W+W-gamma Cross Section and Direct Limits on


  The process e+e- -> W+W-gamma is analysed using the data collected with the
L3 detector at LEP at a centre-of-mass energy of 188.6GeV, corresponding to an
integrated luminosity of 176.8pb^-1. Based on a sample of 42 selected W+W-
candidates containing an isolated hard photon, the W+W-gamma cross section,
defined within phase-space cuts, is measured to be: sigma_WWgamma = 290 +/- 80
+/- 16 fb, consistent with the Standard Model expectation. Including the
process e+e- -> nu nu gamma gamma, limits are derived on anomalous
contributions to the Standard Model quartic vertices W+W- gamma gamma and W+W-Z
gamma at 95% CL: -0.043 GeV^-2 < a_0/Lambda^2 < 0.043 GeV^-2 0.08 GeV^-2 <
a_c/Lambda^2 < 0.13 GeV^-2 0.41 GeV^-2 < a_n/Lambda^2 < 0.37 GeV^-2.

</DOC>
<DOC>
<DOCNO> 170596 </DOCNO>
Indeterminate-length quantum coding


  The quantum analogues of classical variable-length codes are
indeterminate-length quantum codes, in which codewords may exist in
superpositions of different lengths. This paper explores some of their
properties. The length observable for such codes is governed by a quantum
version of the Kraft-McMillan inequality. Indeterminate-length quantum codes
also provide an alternate approach to quantum data compression.

</DOC>
<DOC>
<DOCNO> 9670 </DOCNO>
Photonic Hall Effect in ferrofluids: Theory and Experiments


  An experimental and theoretical study on the Photonic Hall Effect (PHE) in
liquid and gelled samples of ferrofluids is presented. The ferrofluids are
aqueous colloidal suspensions of Fe(_{2})CoO(_{4}) particles, which can be
considered as anisotropic and absorbing Rayleigh scatterers.
  The PHE is found to be produced by the orientation of the magnetic moments of
the particles, as is also the case for the Faraday effect. The dependence of
the PHE with respect to the concentration of the scatterers, the magnetic field
and the polarization of the incident light is measured in liquid and in gelled
samples and is compared to a simple model based on the use of a scattering
matrix and the single scattering approximation.

</DOC>
<DOC>
<DOCNO> 67896 </DOCNO>
Possible Cosmological Implications of the Quark-Hadron Phase Transition


  We study the quark-hadron phase transition within an effective model of QCD,
and find that in a reasonable range of the main parameters of the model, bodies
with quark content between $10^{-2}$ and 10 solar masses can have been formed
in the early universe. In addition, we show that a significant amount of
entropy is released during the transition. This may imply the existence of a
higher baryon number density than what is usually expected at temperatures
above the QCD scale. The cosmological QCD transition may then provide a natural
way for decreasing the high baryon asymmetry created by an Affleck-Dine like
mechanism down to the value required by primordial nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 12435 </DOCNO>
Non-Quantized Penetration of Magnetic Field in the Vortex State of


  As first pointed out by Bardeen and Ginzburg in the early sixties, the amount
of magnetic flux carried by vortices depends on their distance to the sample
edge and can be smaller than one flux quantum, f0 = h/2e. In bulk
superconductors, this reduction of flux becomes negligible already at submicron
distances from the edge but, in thin films, the effect may survive at much
larger distances. In the absence of any experimental observation, such flux
reduction is perceived to be an exotic or unimportant effect, and it is often
assumed that magnetic field enters type-II superconductors in units of f0. Here
we report the measurements of the amount of flux associated with the entrance
of individual vortices in a superconducting film and show that the flux that
they bring in, always differs substantially from f0. We have observed vortices
that carry as little as 0.001 f0 as well as seemingly "negative vortices" whose
penetration leads to the expulsion of magnetic field. We distinguish two
phenomena responsible for non-quantized flux penetration: the finite-size
effect and a non-linear screening of magnetic field in the presence of a
surface barrier. The latter effect has previously not been considered but is
likely to cause non-quantized penetration in many cases.

</DOC>
<DOC>
<DOCNO> 100706 </DOCNO>
When Does the Positive Semidefiniteness Constraint Help In Lifting


  We study the lift-and-project procedures of Lov\'asz and Schrijver for 0-1
integer programming problems. We prove that the procedure using the positive
semidefiniteness constraint is not better than the one without it, in the worst
case. Various examples are considered. We also provide geometric conditions
characterizing when the positive semidefiniteness constraint does not help.

</DOC>
<DOC>
<DOCNO> 69716 </DOCNO>
Effective Field Theory at Moderate Nuclear Density


  Effective field theory of the in-medium nucleon-nucleon interaction is
considered. The effective range parameters are found to be of a natural scale.
The low density limit is discussed both in perturbative and nonperturbative
situations. In the nonperturbative case the attractive character of the
nucleon-nucleon interactions in the $^{1}S_0$ channel leads to the nuclear
superfluidity which is analyzed in the framework of the renormalization group.
The numerical values of the corresponding energy gap are in agreement with
results obtained by more more traditional many-body techniques. The S-wave part
of potential energy per particle is calculated for different values of nuclear
density. The role of pion and many-body effects is discussed. Problems and
challenges in constructing the chiral theory of nuclear matter are outlined.

</DOC>
<DOC>
<DOCNO> 101829 </DOCNO>
Singular Asymptotics Lemma and Push-Forward Theorem


  The Singular Asymptotics Lemma by Br\"uning and Seeley and the Push-Forward
 Theorem by Melrose lie at the very heart of their respective approaches to
singular analysis. We review both and show that they deal with the same basic
problem, giving solutions that emphasize different aspects of it. This also
points to a possible common extension.

</DOC>
<DOC>
<DOCNO> 101814 </DOCNO>
Multi-channel phase-equivalent transformation and supersymmetry


  Phase-equivalent transformation of local interaction is generalized to the
multi-channel case. Generally, the transformation does not change the number of
the bound states in the system and their energies. However, with a special
choice of the parameters, the transformation removes one of the bound states
and is equivalent to the multi-channel supersymmetry transformation recently
suggested by Sparenberg and Baye. Using the transformation, it is also possible
to add a bound state to the discrete spectrum of the system at a given energy
$E<0$ if the angular momentum at least in one of the coupled channels $l\ge 2$.

</DOC>
<DOC>
<DOCNO> 8405 </DOCNO>
Trapped atomic condensates with anisotropic interactions


  We study the ground state properties of trapped atomic condensates with
electric field induced dipole-dipole interactions. A rigorous method for
constructing the pseudo potential in the spirit of ladder approximation is
developed for general non-spherical (polarized) particles interacting
anisotropically. We discuss interesting features not previously considered for
currently available alkali condensates. In addition to provide a quantitative
assessment for controlling atomic interactions with electric fields, our
investigation may also shed new light into the macroscopic coherence properties
of the Bose-Einstein condensation (BEC) of dilute interacting atoms.

</DOC>
<DOC>
<DOCNO> 10370 </DOCNO>
Variety and Volatility in Financial Markets


  We study the price dynamics of stocks traded in a financial market by
considering the statistical properties both of a single time series and of an
ensemble of stocks traded simultaneously. We use the $n$ stocks traded in the
New York Stock Exchange to form a statistical ensemble of daily stock returns.
For each trading day of our database, we study the ensemble return
distribution. We find that a typical ensemble return distribution exists in
most of the trading days with the exception of crash and rally days and of the
days subsequent to these extreme events. We analyze each ensemble return
distribution by extracting its first two central moments. We observe that these
moments are fluctuating in time and are stochastic processes themselves. We
characterize the statistical properties of ensemble return distribution central
moments by investigating their probability density functions and temporal
correlation properties. In general, time-averaged and portfolio-averaged price
returns have different statistical properties. We infer from these differences
information about the relative strength of correlation between stocks and
between different trading days. Lastly, we compare our empirical results with
those predicted by the single-index model and we conclude that this simple
model is unable to explain the statistical properties of the second moment of
the ensemble return distribution.

</DOC>
<DOC>
<DOCNO> 121763 </DOCNO>
The critical velocity effect as a cause for the H\alpha emission from


  Observations show significant H\alpha-emissions in the Galactic halo near the
edges of cold gas clouds of the Magellanic Stream. The source for the
ionization of the cold gas is still a widely open question. In our paper we
discuss the critical velocity effect as a possible explanation for the observed
H\alpha-emission. The critical velocity effect can yield a fast ionization of
cold gas if this neutral gas passes through a magnetized plasma under suitable
conditions. We show that for parameters that are typical for the Magellanic
Stream the critical velocity effect has to be considered as a possible
ionization source of high relevance.

</DOC>
<DOC>
<DOCNO> 150850 </DOCNO>
The Image of Self Intersecting QCD Strings in Four Dimensions


  We numerically examine the self-dual solutions of self-intersecting strings
immersed in four dimensions. We find that open torus knots have topologies that
can support monopole/anti-monopole as well as q-qbar production and
annihilation. We give an estimate of the string tension from quark production
rates, show that the intersection number for torus-knots is 4(p-q), and discuss
a chiral symmetry breaking mechanism due to self-intersections. We supply a
MAPLE program that can annimate the torus-knot solutions. These annimations can
be found at http://www-hep.physics.uiowa.edu/~bacus/research.html under the
``Animation Control Panel''.

</DOC>
<DOC>
<DOCNO> 72103 </DOCNO>
Structure Functions for the Virtual and Real Photons


  Development of concepts related to the photon and its high energy hadronic
interaction is briefly reviewed. A photon considered as an ideal probe of
hadron structure, paradoxically is also considered as an ideal target to test
the perturbative QCD. The present status of the theoretical and experimental
analysis of the structure functions for a virtual and real photon is presented.

</DOC>
<DOC>
<DOCNO> 80875 </DOCNO>
Maxwell Theory from Matrix Model


  We present a scenario for deriving Maxwell theory from IIB matrix model. Four
dimensional spacetime and theories on it relate different dimensional ones by
applying appropriate limits of the backgrounds of matrix model. It is
understood by looking at open strings bits as bi-local fields on the spacetime,
which are decoupled from the bulk in the limits. The origin of
electric-magnetic duality is also discussed in matrix model.

</DOC>
<DOC>
<DOCNO> 116471 </DOCNO>
Scale Dependent Dimensionality


  We argue that dimensionality is not absolute, but that it depends on the
scale of resolution, from the Planck to the macro scale.

</DOC>
<DOC>
<DOCNO> 40561 </DOCNO>
A Luminosity Spectrometer for the Zeus Experiment at HERA


  The HERA luminosity upgrade is expected to generate two major problems in the
current method of luminosity determination which is based on counting
brehmsstrahlung photons: damage of the calorimeter monitor due to high primary
synchrotron radiation and large multiple event (pile-up) corrections. The
luminosity spectrometer presented in this talk, is a novel method that reduces
the impact of these problems in the luminosity measurement and is expected to
yield a total systematic uncertainty of 1.4%. The spectrometer counts
brehmsstrahlung photon conversions in the beam pipe exit window using two small
calorimeters (former ZEUS beam pipe calorimeters) symmetrically placed away
from the synchrotron radiation plane. The photon conversion rate is measured by
counting electron-positron (ep) coincidences in the calorimeters. The ep
acceptance is measured using a third calorimeter (6 meter tagger) which tags
the brehmsstrahlung electrons. The electron-positron pair is separated by a
small dipole magnet.

</DOC>
<DOC>
<DOCNO> 178908 </DOCNO>
Nucleon number dependence of the onset of anomalous J/psi suppression


  We point out that data on the onset of anomalous J/psi suppression as a
function of nucleon numbers A and B could provide information on the dynamics
of nuclear interactions. In particular the models of anomalous J/psi
suppression by Blaizot and Ollitrault (BO) and by Kharzeev, Lourenco, Nardi and
Satz (KLNS) are based on different assumptions on the dynamics of nuclear
collisions and lead to different predictions of the dependence of the onset of
anomalous J/psi suppression on nucleon numbers of colliding nuclei. The data on
this onset as function of A and B could become a tool for the study of the
dynamics of nuclear collisions and bring further evidence on J/psi suppression
by new form of hadronic matter, possibly Quark-Gluon Plasma.
  In particular we propose to study J/\psi suppression in A+Pb interaction with
nucleon number of A between 58 and 73 or a bit higher.

</DOC>
<DOC>
<DOCNO> 68635 </DOCNO>
Could a Slepton be the Zee boson?


  We study the feasibility of incorporating the popular Zee model for neutrino
mass in the framework of the supersymmetric standard model. While a singlet
slepton has the right quantum number to play the role of the Zee charged scalar
boson, the SUSY framework introduces extra contributions. We derive conditions
for the Zee contributions to dominate, hence retaining the flavor of the Zee
model.

</DOC>
<DOC>
<DOCNO> 100421 </DOCNO>
Banach space representations and Iwasawa theory


  The lack of a $p$-adic Haar measure causes many methods of traditional
representation theory to break down when applied to continuous representations
of a compact $p$-adic Lie group $G$ in Banach spaces over a given $p$-adic
field $K$. For example, Diarra showed that the abelian group $G=\dZ$ has an
enormous wealth of infinite dimensional, topologically irreducible Banach space
representations.
  We therefore address the problem of finding an additional ''finiteness''
condition on such representations that will lead to a reasonable theory. We
introduce such a condition that we call ''admissibility''. We show that the
category of all admissible $G$-representations is reasonable -- in fact, it is
abelian and of a purely algebraic nature -- by showing that it is
anti-equivalent to the category of all finitely generated modules over a
certain kind of completed group ring $K[[G]]$.
  As an application of our methods we determine the topological irreducibility
as well as the intertwining maps for representations of $GL_2(\dZ)$ obtained by
induction of a continuous character from the subgroup of lower triangular
matrices.

</DOC>
<DOC>
<DOCNO> 169734 </DOCNO>
Quantum Phase Transitions in a Linear Ion Trap


  We show that the quantum phase transition of the Tavis-Cummings model can be
realised in a linear ion trap of the kind proposed for quantum computation. The
Tavis-Cummings model describes the interaction between a bosonic degree of
freedom and a collective spin. In an ion trap, the collective spin system is a
symmetrised state of the internal electronic states of N ions, while the
bosonic system is the vibrational degree of freedom of the centre of mass mode
for the ions.

</DOC>
<DOC>
<DOCNO> 116466 </DOCNO>
The Chandra X-Ray Observatory's Radiation Environment and the AP-8/AE-8


  The Chandra X-ray Observatory (CXO) was launched on July 23, 1999 and reached
its final orbit on August 7, 1999. The CXO is in a highly elliptical orbit,
approximately 140,000 km x 10,000 km, and has a period of approximately 63.5
hours (~ 2.65 days). It transits the Earth's Van Allen belts once per orbit
during which no science observations can be performed due to the high radiation
environment. The Chandra X-ray Observatory Center (CXC) currently uses the
National Space Science Data Center's ``near Earth'' AP-8/AE-8 radiation belt
model to predict the start and end times of passage through the radiation
belts. However, our scheduling software uses only a simple dipole model of the
Earth's magnetic field. The resulting B, L magnetic coordinates, do not always
give sufficiently accurate predictions of the start and end times of transit of
the Van Allen belts. We show this by comparing to the data from Chandra's
on-board radiation monitor, the EPHIN (Electron, Proton, Helium Instrument
particle detector) instrument. We present evidence that demonstrates this
mis-timing of the outer electron radiation belt as well as data that also
demonstrate the significant variablity of one radiation belt transit to the
next as experienced by the CXO. We also present an explanation for why the
dipole implementation of the AP-8/AE-8 model is not ideally suited for the CXO.
Lastly, we provide a brief discussion of our on-going efforts to identify a
model that accounts for radiation belt variability, geometry, and one that can
be used for observation scheduling purposes.

</DOC>
<DOC>
<DOCNO> 70462 </DOCNO>
One-loop results for the quark-gluon vertex in arbitrary dimension


  Results on the one-loop quark-gluon vertex with massive quarks are reviewed,
in an arbitrary covariant gauge and in arbitrary space-time dimension. We show
how it is possible to get on-shell results from the general off-shell
expressions. The corresponding Ward-Slavnov-Taylor identity is discussed.

</DOC>
<DOC>
<DOCNO> 71244 </DOCNO>
Discrete Wilson Lines in N=1 D=4 Type IIB Orientifolds: A Systematic


  We develop techniques to construct general discrete Wilson lines in
four-dimensional N=1 Type IIB orientifolds, their T-dual realization
corresponds to branes positioned at the orbifold fixed points. The explicit
order two and three Wilson lines along with their tadpole consistency
conditions are given for D=4 N=1 Z_6 Type IIB orientifold. The systematic
search for all models with general order three Wilson lines leads to a small
class of inequivalent models. There are only two inequivalent classes of a
potentially phenomenologically interesting model that has a possible
SU(3)_{color} x SU(2)_L x SU(2)_R x U(1)_{B-L} gauge structure, arising from a
set of branes located at the Z_6 orbifold fixed point. We calculate the
spectrum and Yukawa couplings for this model. On the other hand, introduction
of anti-branes allows for models with three families and realistic gauge group
assignment, arising from branes located at the Z_3 orbifold fixed points.

</DOC>
<DOC>
<DOCNO> 71100 </DOCNO>
On the Emerging Phenomenology of <(A_\mu)^2>


  We discuss phenomenology of the vacuum condensate <(A_\mu)^2> in pure gauge
theories, where A_\mu is the gauge potential. Both Abelian and non-Abelian
cases are considered. In case of the compact U(1) the non-perturbative part of
the condensate <(A_\mu)^2> is saturated by monopoles. In the non-Abelian case,
a two-component picture for the condensate is presented according to which
finite values of order \Lambda_{QCD}^2 are associated both with large and short
distances. We obtain a lower bound on the <(A_\mu)^2> by considering its change
at the phase transition. Numerically, it produces an estimate similar to other
measurements. Possible physical manifestations of the condensate are discussed.

</DOC>
<DOC>
<DOCNO> 178687 </DOCNO>
Spin polarisabilities of the nucleon at NLO in the chiral expansion


  We present a calculation of the fourth-order (NLO) contribution to
spin-dependent Compton scattering in heavy-baryon chiral perturbation theory,
and we give results for the four spin polarisabilities. These results have been
presented before, in hep-ph/0002133. Here we address the issue of whether
one-particle reducible graphs in the heavy baryon theory contribute to the
polarisabilities.

</DOC>
<DOC>
<DOCNO> 80790 </DOCNO>
Phase structure and critical temperature of two-flavor QCD with a


  We study the finite-temperature phase structure and the transition
temperature of QCD with two flavors of dynamical quarks on a lattice with the
temporal size $N_t=4$, using a renormalization group improved gauge action and
the Wilson quark action improved by the clover term. The region of a
parity-broken phase is identified, and the finite-temperature transition line
is located on a two-dimensional parameter space of the coupling ($\beta=6/g^2$)
and hopping parameter $K$. Near the chiral transition point, defined as the
crossing point of the critical line of the vanishing pion mass and the line of
finite-temperature transition, the system exhibits behavior well described by
the scaling exponents of the three-dimensional O(4) spin model. This indicates
a second-order chiral transition in the continuum limit. The transition
temperature in the chiral limit is estimated to be $T_c = 171(4)$ MeV.

</DOC>
<DOC>
<DOCNO> 178515 </DOCNO>
Total cross section for p-d breakup below 30 MeV


  The total cross section for p-d breakup is studied in terms of the elastic
S-matrix through the unitary condition. Calculations using the complex Kohn
variational method along with the Pair Correlated Hyperspherical Harmonic basis
are presented. The results have been restricted to energies below Ep=30 MeV
where Coulomb effects are expected to be sizable and are compared to the
existing data. Two different measurements have been found in the literature: 40
years ago, Gibbons and Macklin (1959); and 26 years ago, Carlosn et al. (1973).
The calculations are found to be in reasonable agreement with these old data,
though a discrepancy is observed near the deuteron breakup threshold. Moreover,
a detailed analysis of the contributions to the observable from different
partial waves has been presented. Unexpectedly, the main contribution for a
wide range of energies has been detected in the J=3/2- state.

</DOC>
<DOC>
<DOCNO> 116367 </DOCNO>
On the effect of small-scale oceanic variability on topography-generated


  Small-scale oceanic motions, in combination with bottom topography, induce
mean large-scale along-isobaths flows. The direction of these mean flows is
usually found to be anticyclonic (cyclonic) over bumps (depressions). Here we
employ a quasigeostrophic model to show that the current direction of these
topographically induced large-scale flows can be reversed by the small-scale
variability. This result addresses the existence of a new bulk effect from the
small-scale activity that could have strong consequences on the circulation of
the world's ocean.

</DOC>
<DOC>
<DOCNO> 68124 </DOCNO>
Gravity, particle physics and their unification


  We explain the need for a theory of quantum gravity and some general ideas
about string theory, including the idea of the derivation of the Hawking
Bekenstein entropy formula for extremal black holes. We then give a general
description of the correspondence between the large N limit of certain gauge
theories and string theory on spacetimes with boundaries.

</DOC>
<DOC>
<DOCNO> 99625 </DOCNO>
Examples and Counterexamples for Existence of Categorical Quotients


  We give examples for existence and non-existence of categorical quotients for
algebraic group actions in the categories of algebraic varieties and
prevarieties. All our examples are subtorus actions on toric varieties.

</DOC>
<DOC>
<DOCNO> 100846 </DOCNO>
Ricci-flat Kaehler metrics on canonical bundles


  We prove the existence of a (unique) S^1-invariant Ricci-flat Kaehler metric
on a neighbourhood of the zero section in the canonical bundle of a
real-analytic Kaehler manifold X, extending the metric on X.

</DOC>
<DOC>
<DOCNO> 102839 </DOCNO>
Noncommutative Generalized NS and Super Matrix KdV Systems from a


  A noncommutative version of the (anti-) self-dual Yang-Mills equations is
shown to be related via dimensional reductions to noncommutative formulations
of the generalized (SO(3)/SO(2)) nonlinear Schrodinger (NS) equations, of the
super-Korteweg- de Vries (super-KdV) as well as of the matrix KdV equations.
Noncommutative extensions of their linear systems and bicomplexes associated to
conserved quantities are discussed.

</DOC>
<DOC>
<DOCNO> 118715 </DOCNO>
Molecular Abundances in the Atmosphere of the T Dwarf Gl 229B


  We present new, high resolution, infrared spectra of the T dwarf Gliese 229B
in the J, H, and K bandpasses. We analyze each of these as well as previously
published spectra to determine its metallicity and the abundances of NH3 and CO
in terms of the surface gravity of Gl 229B, which remains poorly constrained.
The metallicity increases with increasing gravity and is below the solar value
unless Gl 229B is a high-gravity brown dwarf with log g(cgs) ~ 5.5. The NH3
abundance is determined from both the H and the K band spectra which probe two
different levels in the atmosphere. We find that the abundance from the K band
data is well below that expected from chemical equilibrium, which we interpret
as strong evidence for dynamical transport of NH3 in the atmosphere. This is
consistent with the previous detection of CO and provides additional
constraints on the dynamics of the atmosphere of this T dwarf.

</DOC>
<DOC>
<DOCNO> 7634 </DOCNO>
Evidence for a transition from a bulk Meissner-state to a spontaneous


  From magnetisation measurements we provide evidence that the ferromagnetic
superconductor RuSr$_{2}$GdCu$_{2}$O$_{8}$ with \QTR{it}{T}$_{c}$=45 K and
\QTR{it}{T}$_{M}$=137 K exhibits a sizeable diamagnetic signal at low
temperature (\QTR{it}{T}<\QTR{it}{T}$^{\QTR{it}{ms}}$=30 K) and low magnetic
field (\QTR{it}{H}$^{ext}$<30 Oe), corresponding to a bulk Meissner-phase. At
intermediate temperatures,
\QTR{it}{T}$^{\QTR{it}{ms}}$<\QTR{it}{T}<\QTR{it}{T}$_{c}$, a spontaneous
vortex phase forms which is characterized by unique thermal hysteresis effects.
We argue that a recent negative report [C.W. Chu et al., cond-mat/9910056]
regarding the Meissner-effect in Ru-1212 can be explained by impurity
scattering or grain size effects.

</DOC>
<DOC>
<DOCNO> 170661 </DOCNO>
Why am I me? and why is my world so classical?


  This is an attempt to apply Nagel's distinction between internal and external
statements to the interpretation of quantum mechanics. I propose that this
distinction resolves the contradiction between unitary evolution and the
projection postulate. I also propose a more empirically realistic version of
the projection postulate. The result is a version of Everett's relative-state
interpretation, including a proposal for how probabilities are to be
understood.
  Based on a talk given at the 9th UK Foundations of Physics meeting in
Birmingham on 12 September 2000.

</DOC>
<DOC>
<DOCNO> 9488 </DOCNO>
Carrier and Light Trapping in Graded Quantum Well Laser Structures


  We investigated the carrier and light trapping in GaInAs/AlGaAs single
quantum well laser structures by means of time resolved photoluminescence and
Raman spectroscopy. The influence of the shape and depth of the confinement
potential and of the cavity geometry was studied by using different AlGaAs/GaAs
short-period superlattices as barriers. Our results show that grading the
optical cavity improves considerably both carrier and light trapping in the
quantum well, and that the trapping efficiency is enhanced by increasing the
graded confining potential.

</DOC>
<DOC>
<DOCNO> 178863 </DOCNO>
Quark-meson coupling model for a nucleon


  We considered the quark-meson coupling model for a nucleon. The model
describes a nucleon as an MIT bag, in which quarks are coupled to the scalar
and the vector mesons. A set of coupled equations for the quark and the meson
fields are obtained and are solved in a self-consistent manner. We show that
the mass of a dressed MIT bag interacting with $\sigma$- and $\omega$-meson
fields differs considerably from the mass of the free MIT bag. The effects of
the density-dependent bag constant are investigated. The results of our
calculations imply that the self-energy of the bag in the quark-meson coupling
model is significant and needs to be considered in doing the calculations for
nuclear matter or finite nuclei.

</DOC>
<DOC>
<DOCNO> 101925 </DOCNO>
On Rugina's System of Thought


  In this article one investigates Rugina's Orientation Table and one gives
particular examples for several of its seven models. Leon Walras's Economics of
Stable Equilibrium and Keynes's Economics of Disequilibrium are combined in
Rugina's Orientation Table in systems which are s% stable and 100-s% unstable,
where s may be 100, 95, 65, 50, 35, 5, and 0. The Classical Logic and Modern
Logic are united in Rugina's Integrated Logic, and then generalized in the
Neutrosophic Logic.

</DOC>
<DOC>
<DOCNO> 85393 </DOCNO>
Cosmic Censorship: The Role of Quantum Gravity


  The cosmic censorship hypothesis introduced by Penrose thirty years ago is
still one of the most important open questions in {\it classical} general
relativity. In this essay we put forward the idea that cosmic censorship is
intrinsically a {\it quantum gravity} phenomena. To that end we construct a
gedanken experiment in which cosmic censorship is violated within the purely
{\it classical} framework of general relativity. We prove, however, that {\it
quantum} effects restore the validity of the conjecture. This suggests that
classical general relativity is inconsistent and that cosmic censorship might
be enforced only by a quantum theory of gravity.

</DOC>
<DOC>
<DOCNO> 116921 </DOCNO>
Simulation of an Intra-Pulse Interaction Point Feedback for Future


  In future normal-conducting linear colliders, the beams will be delivered in
short bursts with a length of the order of 100 ns. The pulses will be separated
by several ms. In order to maintain high luminosity, feedback is necessary on a
pulse-to-pulse basis. In addition, intra-pulse feedback that can correct beam
positions and angles within one pulse seem technically feasible. The likely
performances of different feedback options are simulated for the NLC (Next
Linear Collider) and CLIC (Compact Linear Collider).

</DOC>
<DOC>
<DOCNO> 102659 </DOCNO>
Hopf group-coalgebras


  We study algebraic properties of Hopf group-coalgebras, recently introduced
by Turaev. We show the existence of integrals and traces for such coalgebras,
and we generalize the main properties of quasitriangular and ribbon Hopf
algebras to the setting of Hopf group-coalgebras.

</DOC>
<DOC>
<DOCNO> 72271 </DOCNO>
Photoabsorption sum rules and quark structure parameters of hadrons


  Following the idea of the quark-hadron duality we present, within the
constituent quark model approach, the relations between different
bremsstrahlung-weihgted integrals of the nucleon resonance photoexcitation
cross sections and correlation functions of the quark dipole moments in the
nucleon ground state. These functions are of interest for checking detailed
quark-configuration structure of the nucleon state vector. Some applications of
this approach in meson sector are made and the role of meson degrees of freedom
in the electromagnetic baryon observables is briefly discussed.

</DOC>
<DOC>
<DOCNO> 116500 </DOCNO>
On the Physical Cause and the Distance of Gamma Ray Bursts and Related


  The modified Lorentz transformation of a distance-dependent special theory of
relativity - which will be briefly summarized - predicts the possibility of
superluminal velocity of very distantly moving material bodies to be connected
with the generation of Cerencov radiation off the quantum vacuum. It is shown
that vacuum Cerencov radiation due to the superluminal propagation of
extraterrestrial spaceprobes in the interstellar space would account for all
known properties of gamma ray bursts (GRBs) and the "afterglow" at lower
frequencies. Distances and other parameter prove to be calculable and the
theoretical results on these grounds to be in good accord with experiment.

</DOC>
<DOC>
<DOCNO> 10502 </DOCNO>
Stripes And Nodal Fermions As Two Sides Of The Same Coin


  One of the central problems in High T_{c} superconductivity is to reconcile
the abundant evidence for stripe-like physics at `short' distances with the
equally convincing evidence for BCS like physics at large distance scales (the
`nodal fermions'). Our central hypothesis is that the duality notion applies:
the superconductor should be viewed as a condensate of topological excitations
associated with the fully ordered stripe phase. As we will argue, the latter
are not only a form of `straighforward' spin and charge order but also involve
a form of `hidden' or `topological' long range order which is also responsible
for the phenomenon of spin-charge separation in 1+1D. The topological
excitation associated with the destruction of this hidden order is of the most
unusual kind. We suggest that the associated disorder field theory has a
geometrical, gravity like structure concurrent with topological phases with no
precedent elsewhere.

</DOC>
<DOC>
<DOCNO> 121904 </DOCNO>
STIS observations of five hot white dwarfs


  We present some early results from a study of five hot DA white dwarf stars,
based on spectra obtained using STIS. All show multiple components in one or
more of the strong resonance absorption lines typically associated with the
stellar photosphere (e.g. C IV, Si IV, N V and O V). Possible relationships
between the non-photospheric velocity components and the interstellar medium or
local stellar environment, are investigated, including contributions from
gravitational redshifting.

</DOC>
<DOC>
<DOCNO> 100287 </DOCNO>
Noncommutative Rational Functions and Farber's Invariants of Boundary


  In [2] M. Farber constructed invariants of m-component boundary links with
values in algebra of noncommutative rational functions. In this paper we
simplify his constructions and express them by using noncommutative
generalizations of determinants introduced by Gelfand and Retakh. In
particular, for every finite-dimensional module N over the algebra of
noncommutative polynomials of m variables we construct a characteristic
rational power series chi(N). If N is an algebraically closed field of
arbitrary characteristic and N is semisimple, the series chi(N) determines N.

</DOC>
<DOC>
<DOCNO> 12245 </DOCNO>
Capacitance, Charge Fluctuations and Dephasing In Coulomb Coupled


  The charge fluctuations of two nearby mesoscopic conductors coupled only via
the long range Coulomb force are discussed and used to find the dephasing rate
which one conductor exerts on the other. The discussion is based on a
formulation of the scattering approach for charge densities and the density
response to a fluctuating potential. Coupling to the Poisson equation results
in an electrically self-consistent description of charge fluctuations. At
equilibrium the low-frequency noise power can be expressed with the help of a
charge relaxation resistance (which together with the capacitance determines
the RC-time of the structure). In the presence of transport the low frequency
charge noise power is determined by a resistance which reflects the presence of
shot noise. We use these results to derive expressions for the dephasing rates
of Coulomb coupled conductors and to find a self-consistent expression for the
measurement time.

</DOC>
<DOC>
<DOCNO> 68494 </DOCNO>
Power-suppressed Thermal Effects from Heavy Particles


  In quantum field theory, heavy particles with mass $M$ much greater than the
temperature $T$ give not only effects suppressed by the Boltzmann factor
$e^{-M/T}$, but also effects suppressed by powers of $T/M$. We show that
power-suppressed terms in equilibrium observables arise from effective
interactions among light particles due to virtual heavy particles. We study a
model introduced by Matsumoto and Yoshimura in which study a model introduced
by Matsumoto and Yoshimura in which heavy bosons interact only through a term
that allows pair annihilation into light particles. We construct an effective
Lagrangian for the light field by integrating out the heavy field, and use it
to calculate the leading power-suppressed terms in the energy density. The
thermal average of the Hamiltonian density for the heavy field includes a term
proportional to $T^6/M^2$, but we show that this term can be eliminated by a
field redefinition and therefore cannot have any physical significance.

</DOC>
<DOC>
<DOCNO> 84084 </DOCNO>
The self-force on a static scalar test-charge outside a Schwarzschild


  The finite part of the self-force on a static scalar test-charge outside a
Schwarzschild black hole is zero. By direct construction of Hadamard's
elementary solution, we obtain a closed-form expression for the minimally
coupled scalar field produced by a test-charge held fixed in Schwarzschild
spacetime. Using the closed-form expression, we compute the necessary external
force required to hold the charge stationary. Although the energy associated
with the scalar field contributes to the renormalized mass of the particle (and
thereby its weight), we find there is no additional self-force acting on the
charge. This result is unlike the analogous electrostatic result, where, after
a similar mass renormalization, there remains a finite repulsive self-force
acting on a static electric test-charge outside a Schwarzschild black hole. We
confirm our force calculation using Carter's mass-variation theorem for black
holes. The primary motivation for this calculation is to develop techniques and
formalism for computing all forces - dissipative and non-dissipative - acting
on charges and masses moving in a black-hole spacetime. In the Appendix we
recap the derivation of the closed-form electrostatic potential. We also show
how the closed-form expressions for the fields are related to the infinite
series solutions.

</DOC>
<DOC>
<DOCNO> 151090 </DOCNO>
S-Duality and Noncommutative Gauge Theory


  It is conjectured that strongly coupled, spatially noncommutative $\CN=4$
Yang-Mills theory has a dual description as a weakly coupled open string theory
in a near critical electric field, and that this dual theory is fully decoupled
from closed strings. Evidence for this conjecture is given by the absence of
physical closed string poles in the non-planar one-loop open string diagram.
The open string theory can be viewed as living in a geometry in which space and
time coordinates do not commute.

</DOC>
<DOC>
<DOCNO> 13303 </DOCNO>
Raman scattering near a quantum critical point


  Electronic Raman scattering experiments in a wide variety of materials
(ranging from mixed-valence materials to Kondo insulators to high-temperature
superconductors) show anomalous behavior in the B_{1g} channel when the system
is on the insulating side of the metal-insulator transition. Here we provide an
exact solution for B_{1g} Raman scattering in the Falicov-Kimball model, show
how these theoretical results are universal near the metal-insulator transition
and show how they produce the two main features seen in experiments near a
quantum critical point: (i) the rapid appearance of low-energy spectral weight
as T is increased from 0 and (ii) the existence of an isosbestic point (where
the Raman response is independent of T at a characteristic frequency).

</DOC>
<DOC>
<DOCNO> 10561 </DOCNO>
X-ray natural circular dichroism


  This paper discusses a theory of natural circular dichroism in the x-ray
region. Integrated spectra are interpreted in terms of microscopic effective
operators, which are derived in the framework of a localised (atomic) model. It
is shown that the generators of a de Sitter group, such as that introduced by
Goshen and Lipkin for nuclear structure, are suitable for describing electronic
properties of non-centrosymmetric crystals.

</DOC>
<DOC>
<DOCNO> 84653 </DOCNO>
Topologically massive magnetic monopoles


  We show that in the Maxwell-Chern-Simons theory of topologically massive
electrodynamics the Dirac string of a monopole becomes a cone in anti-de Sitter
space with the opening angle of the cone determined by the topological mass
which in turn is related to the square root of the cosmological constant. This
proves to be an example of a physical system, {\it a priory} completely
unrelated to gravity, which nevertheless requires curved spacetime for its very
existence. We extend this result to topologically massive gravity coupled to
topologically massive electrodynamics in the framework of the theory of Deser,
Jackiw and Templeton. These are homogeneous spaces with conical deficit. Pure
Einstein gravity coupled to Maxwell-Chern-Simons field does not admit such a
monopole solution.

</DOC>
<DOC>
<DOCNO> 118953 </DOCNO>
The Influence of Galactic Outflows on the Formation of Nearby Dwarf


  We show that the gas in growing density perturbations is vulnerable to the
influence of winds outflowing from nearby collapsed galaxies that have already
formed stars. This suggests that the formation of nearby galaxies with masses
less than 10^9 solar masses is likely to be suppressed, irrespective of the
details of galaxy formation. An impinging wind may shock heat the gas of a
nearby perturbation to above the virial temperature, thereby mechanically
evaporating the gas, or the baryons may be stripped from the perturbation
entirely if they are accelerated to above the escape velocity. We show that
baryonic stripping is the most effective of these two processes, because
shock-heated clouds that are too large to be stripped are able to radiatively
cool within a sound-crossing time, limiting evaporation. The intergalactic
medium temperatures and star-formation rates required for outflows to have a
significant influence on the formation of low-mass galaxies are consistent with
current observations, but may soon be examined directly via associated
distortions in the cosmic microwave background, and with near-infrared
observations from the Next Generation Space Telescope, which may detect the
supernovae from early-forming stars.

</DOC>
<DOC>
<DOCNO> 102539 </DOCNO>
Generalized Metrical Multi-Time Lagrange Model for General Relativity


  The paper construct a suitable generalized metrical multi-time Lagrange
geometrical model for both gravitational and electromagnetic fields, in a
general setting. In this construction, the gravitational potentials are
described by a distinguished vertical metrical tensor of the form
$h^{/alpha/beta}e^{2\sigma}/phi_{ij}$.

</DOC>
<DOC>
<DOCNO> 101091 </DOCNO>
Spectrum generating algebra of the C_{\lambda}-extended oscillator and


  The $C_{\lambda}$-extended oscillator spectrum generating algebra is shown to
be a $C_{\lambda}$-extended $(\lambda-1)$th-degree polynomial deformation of
su(1,1). Its coherent states are constructed. Their statistical and squeezing
properties are studied in detail. Such states include both some
Barut-Girardello and the standard $\lambda$-photon coherent states as special
cases.

</DOC>
<DOC>
<DOCNO> 101170 </DOCNO>
New Non-Abelian Zeta Functions for Curves over Finite Fields


  In this paper, we introduce and study two new types of non-abelian zeta
functions for curves over finite fields, which are defined by using (moduli
spaces of) semi-stable vector bundles and non-stable bundles. A Riemann-Weil
type hypothesis is formulated for zeta functions associated to semi-stable
bundles, which we think is more canonical than the other one. All this is
motivated by (and hence explains in a certain sense) our work on non-abelian
zeta functions for number fields.

</DOC>
<DOC>
<DOCNO> 117789 </DOCNO>
The Spectral Variability of Cygnus X-1 at MeV Energies


  In previous work, we have used data from the first three years of the CGRO
mission to assemble a broad-band $\gamma$-ray spectrum of the galactic black
hole candidate Cygnus X-1. Contemporaneous data from the COMPTEL, OSSE and
BATSE experiments on CGRO were selected on the basis of the hard X-ray flux
(45--140 keV) as measured by BATSE. This provided a spectrum of Cygnus X-1 in
its canonical low X-ray state (as measured at energies below 10 keV), covering
the energy range from 50 keV to 5 MeV. Here we report on a comparison of this
spectrum to a COMPTEL-OSSE spectrum collected during a high X-ray state of
Cygnus X-1 (May, 1996). These data provide evidence for significant spectral
variability at energies above 1 MeV. In particular, whereas the hard X-ray flux
{\it decreases} during the high X-ray state, the flux at energies above 1 MeV
{\it increases}, resulting in a significantly harder high energy spectrum. This
behavior is consistent with the general picture of galactic black hole
candidates having two distinct spectral forms at soft $\gamma$-ray energies.
These data extend this picture, for the first time, to energies above 1 MeV.

</DOC>
<DOC>
<DOCNO> 101723 </DOCNO>
Nonlinear boundary value problem of magnetic insulation


  On the basis of generalization of upper and lower solution method to the
singular two point boundary value problems, the existence theorem of solutions
for the system, which models a process of magnetic insulation in plasma is
proved.

</DOC>
<DOC>
<DOCNO> 83122 </DOCNO>
Logic Programs with Compiled Preferences


  We describe an approach for compiling preferences into logic programs under
the answer set semantics. An ordered logic program is an extended logic program
in which rules are named by unique terms, and in which preferences among rules
are given by a set of dedicated atoms. An ordered logic program is transformed
into a second, regular, extended logic program wherein the preferences are
respected, in that the answer sets obtained in the transformed theory
correspond with the preferred answer sets of the original theory. Our approach
allows both the specification of static orderings (as found in most previous
work), in which preferences are external to a logic program, as well as
orderings on sets of rules. In large part then, we are interested in describing
a general methodology for uniformly incorporating preference information in a
logic program. Since the result of our translation is an extended logic
program, we can make use of existing implementations, such as dlv and smodels.
To this end, we have developed a compiler, available on the web, as a front-end
for these programming systems.

</DOC>
<DOC>
<DOCNO> 12972 </DOCNO>
Density of states "width parity" effect in d-wave superconducting


  We calculate the density of states (DOS) in a clean mesoscopic d-wave
superconducting quantum wire, i.e. a sample of infinite length but finite width
$N$. For open boundary conditions, the DOS at zero energy is found to be zero
if $N$ is even, and nonzero if $N$ is odd. At finite chemical potential, all
chains are gapped but the qualtitative differences between even and odd $N$
remain.

</DOC>
<DOC>
<DOCNO> 122349 </DOCNO>
On the spin-up of neutron stars to millisecond pulsars in long-period


  We study the accretion efficiency of neutron stars in long-period binaries,
i.e. with periods longer than about 200d, which accrete from a giant companion.
Using alpha-disc models and taking into account the effect of irradiation of
the accretion disc by the central accretion light source we derive explicit
expressions for the duty cycle and the accretion efficiency in terms of the
parameters of the binary system and the disc instability limit cycle. We show
that the absence of millisecond pulsars in wide binaries with circular orbits
and periods longer than about 200d can be understood as a consequence of the
disc instability if the duration of the quiescent phase between two subsequent
outbursts is at least a few decades.

</DOC>
<DOC>
<DOCNO> 102572 </DOCNO>
Computable Legendrian invariants


  We establish tools to facilitate the computation and application of the
Chekanov-Eliashberg differential graded algebra (DGA), a Legendrian-isotopy
invariant of Legendrian knots in standard contact three-space. More
specifically, we reformulate the DGA in terms of front projection, and
introduce the characteristic algebra, a new invariant derived from the DGA. We
use our techniques to distinguish between several previously indistinguishable
Legendrian knots and links.

</DOC>
<DOC>
<DOCNO> 117819 </DOCNO>
Toy model of obscurational variability in active galactic nuclei


  We propose an explanation of the variability of AGN based on a cloud model of
accretion onto a black hole. These clouds, present at a distance of 10-100
Schwarzschild radii, possibly come from the disrupted innermost disk and they
can partially obscure the central X-ray source due to their extreme Compton
optical depth. We consider the implications of this scenario using a toy model
of AGN spectra and support the results with full radiative transfer
computations from the codes TITAN and NOAR. We show that small random
rearrangements of the cloud distribution can happen on timescales of the order
of 10^2 - 10^6 s and may lead to relatively high variability amplitude in the
X-ray band if the mean covering factor is large. The normalized variability
amplitude in the UV band is either the same as in the X-ray band, if the
contribution from the dark sides of the clouds to the UV band is negligible, or
it is smaller. The X-ray spectrum should basically preserve its spectral shape
even during the high amplitude variability, within the frame of our model.

</DOC>
<DOC>
<DOCNO> 11626 </DOCNO>
Diffusion with rearranging traps


  A model for diffusion on a cubic lattice with a random distribution of traps
is developed. The traps are redistributed at certain time intervals. Such
models are useful for describing systems showing dynamic disorder, such as
ion-conducting polymers. In the present model the traps are infinite, unlike an
earlier version with finite traps, this model has a percolation threshold. For
the infinite trap version a simple analytical calculation is possible and the
results agree qualitatively with simulation.

</DOC>
<DOC>
<DOCNO> 152152 </DOCNO>
D-dimensional Ideal Quantum Gases in $Ar^{n}+Br^{-n}$ Potential


  The paper is concerned with thermostatistics of both $D$-dimensional Bose and
Fermi ideal gases in a confining potential of type $Ar^{n}+Br^{-n}$. The
investigation is performed in the framework of the semiclassical approximation.
Some physical quantities for such systems are derived, like density of states,
density profiles and number of particles. Bose-Einstein condensation (BEC) is
discussed in the high and low temperature regimes.

</DOC>
<DOC>
<DOCNO> 39977 </DOCNO>
Parametrization of polarized parton distributions


  We report the polarized parton distributions proposed by the Asymmetry
Analysis Collaboration (AAC). Using parametrized distributions at Q^2=1 GeV^2
and measured A_1 data, we determine optimum polarized distributions in the
leading order (LO) and next-to-leading order (NLO). We find that the polarized
antiquark distribution is not well determined particularly at small x. It could
lead to a rather small quark spin content in comparison with usually-quoted
values of 10-30%. In our analysis, it varies from 5% to 28% depending on the
small-x extrapolation. It is necessary to have small-x (<10^{-3}) data for
precise determination. In addition, the large-x region should be also studied
for \Delta q-bar, which cannot be determined solely by g_1. We propose three
sets of distributions as the longitudinally polarized parton distribution
functions.

</DOC>
<DOC>
<DOCNO> 72186 </DOCNO>
Phenomenology of multiple parton radiation in semi-inclusive


  In the current region of semi-inclusive deep-inelastic scattering, most
events are accompanied by intensive radiation of soft and collinear partons
which cannot be reliably described at any fixed order of perturbative QCD. In
this paper, a resummation formalism that describes such multiple parton
radiation is compared to the HERA data on semi-inclusive DIS, including the
distributions of energy flow and charged particle multiplicity. We show that
the resummation of multiple parton radiation improves the agreement between the
theory and the data. We make some suggestions on further experimental study of
multiple parton radiation at HERA.

</DOC>
<DOC>
<DOCNO> 7785 </DOCNO>
Transition into a low temperature superconducting phase of


  We have found a sharp transition in the vortex creep rates at a temperature
T^\ast=0.05 T_c in a single crystal of Sr_2RuO_4 (T_{c}=1.03 K) by means of
magnetic relaxation measurements. For T<T^\ast, the initial creep rates drop to
undetectable low levels. One explanation for this transition into a phase with
such extremely low vortex creep is that the low-temperature phase of Sr_2RuO_4
breaks time reversal symmetry. In that case, degenerate domain walls separating
discreetly degenerate states of a superconductor can act as very strong pinning
centers.

</DOC>
<DOC>
<DOCNO> 100183 </DOCNO>
Pre-Lagrangian Submanifolds in Contact Manifolds


  In this paper we prove that there does not exists any closed Pre-Lagrangian
submanifolds in any closed contact manifolds by using the $J-$holomorphic
curves and Gromov's nonlinear Fredholm alternative.

</DOC>
<DOC>
<DOCNO> 170161 </DOCNO>
Classical trajectories compatible with quantum mechanics


  Consider any stationary Schroedinger wave equation (SWE) solution $psi (x)$
for a particle. The corresponding PDF on position QTR{em}{x} of the particle is
QTR{em}{p}$_{X}(x)=|psi (x)|^{2}$. There is a classical trajectory
QTR{em}{x(t)} for the particle that is consistent with this PDF. The trajectory
is unique to within an additive constant corresponding to an initial condition
QTR{em}{x(0).} However the value of QTR{em}{x(0)} cannot be known. As an
example, a free particle in its ground state in a box of length QTR{em}{L}
obeys a classical trajectory QTR{em}{x/L - (1/2}$pi)sin (2pi x/L)+t_{0}=t.$ The
constant QTR{em}{t}$_{0}$ is an unknowable time displacement. Momentum values,
however, cannot be determined by merely differentiating QTR{em}{d/dt} the
trajectory QTR{em}{x(t)} and, instead, follow the usual quantification rules of
Heisenberg's. This permits position and momentum to remain complementary
variables. Our approach is fundamentally different from that of D. Bohm.

</DOC>
<DOC>
<DOCNO> 119493 </DOCNO>
ASCA Observations of NLS1s


  The study of NLS1s using ASCA has many advantages. A representative sample
can be studied; to date, observations of more than 30 NLS1s have been made.
ASCA observations are conducted contiguously, so their X-ray variability
properties can be studied systematically. ASCA detectors have a broad band pass
and moderate energy resolution, properties which allow their complex X-ray
spectrum to be deconvolved. ASCA observations have revealed that a soft excess
extending up to 1 keV is frequently found in the X-ray spectra from NLS1s. The
hard X-ray photon index has been shown to be systematically steeper than in
Seyfert 1 galaxies with broad optical lines. NLS1s also exhibit larger
amplitude variability than broad-line Seyferts of similar hard X-ray
luminosity. On occasion, features in the soft X-ray band have been detected
that appear to be specific to NLS1s; ionized iron lines have also been
observed. These results have been fundamental for building our current picture
of the X-ray emission from NLS1s. Many of the properties can be explained if
the specific accretion rate is larger in NLS1s than in Seyfert 1 galaxies with
broad optical lines. NLS1s may exemplify an extreme state of an intrinsic
physical parameter and therefore their study may lead to an enhanced
understanding of AGN in general. This proceedings contribution has two parts.
First I describe and discuss some of the results obtained from a study of the
X-ray variability in NLS1s using ASCA data (Leighly 1999ab). Then, I discuss
the results from our HST observations of NLS1s that were first presented during
this meeting (Leighly & Halpern 2000).

</DOC>
<DOC>
<DOCNO> 120252 </DOCNO>
Induced Scattering and Two-Photon Absorption of Alfven Waves with


  The equation for temporary evolution of spectral energy of collisionless
Alfven waves is derived in framework of weak turbulence theory. The main
nonlinear processes for such conditions are induced scattering and two quantum
absorption of Alfven waves by thermal ions. The equation for velocity
distribution of thermal particles is derived that describes diffusion in
momentum space due to this nonlinear processes. Comparison is done with the
results of another authors. Results obtained are qualitatively differ from the
ones obtained for the case of Alfven waves propagation along mean magnetic
field.

</DOC>
<DOC>
<DOCNO> 80667 </DOCNO>
Domain Wall Fermions in Quenched Lattice QCD


  We study the chiral properties and the validity of perturbation theory for
domain wall fermions in quenched lattice QCD at beta=6.0. The explicit chiral
symmetry breaking term in the axial Ward-Takahashi identity is found to be very
small already at Ns=10, where Ns is the size of the fifth dimension, and its
behavior seems consistent with an exponential decay in Ns within the limited
range of Ns we explore. From the fact that the critical quark mass, at which
the pion mass vanishes as in the case of the ordinary Wilson-type fermion,
exists at finite Ns, we point out that this may be a signal of the parity
broken phase and investigate the possible existence of such a phase in this
model at finite Ns. The rho and pi meson decay constants obtained from the
four-dimensional local currents with the one-loop renormalization factor show a
good agreement with those obtained from the conserved currents.

</DOC>
<DOC>
<DOCNO> 11436 </DOCNO>
Network robustness and fragility: Percolation on random graphs


  Recent work on the internet, social networks, and the power grid has
addressed the resilience of these networks to either random or targeted
deletion of network nodes. Such deletions include, for example, the failure of
internet routers or power transmission lines. Percolation models on random
graphs provide a simple representation of this process, but have typically been
limited to graphs with Poisson degree distribution at their vertices. Such
graphs are quite unlike real world networks, which often possess power-law or
other highly skewed degree distributions. In this paper we study percolation on
graphs with completely general degree distribution, giving exact solutions for
a variety of cases, including site percolation, bond percolation, and models in
which occupation probabilities depend on vertex degree. We discuss the
application of our theory to the understanding of network resilience.

</DOC>
<DOC>
<DOCNO> 69600 </DOCNO>
Why the Cosmological Constant Problem is Hard


  We consider a recent proposal to solve the cosmological constant problem
within the context of brane world scenarios with infinite volume extra
dimensions. In such theories bulk can be supersymmetric even if brane
supersymmetry is completely broken. The bulk cosmological constant can
therefore naturally be zero. Since the volume of the extra dimensions is
infinite, it might appear that at large distances one would measure the bulk
cosmological constant which vanishes. We point out a caveat in this argument.
In particular, we use a concrete model, which is a generalization of the
Dvali-Gabadadze-Porrati model, to argue that in the presence of non-zero brane
cosmological constant at large distances such a theory might become effectively
four dimensional. This is due to a mass gap in the spectrum of bulk graviton
modes. In fact, the corresponding distance scale is set precisely by the brane
cosmological constant. This phenomenon appears to be responsible for the fact
that bulk supersymmetry does not actually protect the brane cosmological
constant.

</DOC>
<DOC>
<DOCNO> 102536 </DOCNO>
Whitehead modules over large principal ideal domains


  We consider the Whitehead problem for principal ideal domains of large size.
It is proved, in ZFC, that some p.i.d.'s of size >= aleph_{2} have non-free
Whitehead modules even though they are not complete discrete valuation rings.

</DOC>
<DOC>
<DOCNO> 100068 </DOCNO>
Cauchy-Riemann geometry and contact topology in three dimensions


  We introduce a global Cauchy-Riemann($CR$)-invariant and discuss its behavior
on the moduli space of $CR$-structures. We argue that this study is related to
the Smale conjecture in 3-topology and the problem of counting complex
structures. Furthermore, we propose a contact-analogue of Ray-Singer's analytic
torsion. This ``contact torsion'' is expected to be able to distinguish among
``contact lens'' spaces. We also propose the study of a certain kind of
monopole equation associated with a contact structure.

</DOC>
<DOC>
<DOCNO> 84915 </DOCNO>
Numerical Data-Processing Simulations of Microarcsecond Classical and


  The accuracy of astrometric observations conducted via a space-borne optical
interferometer orbiting the Earth is expected to approach a few
microarcseconds. Data processing of such extremely high-precision measurements
requires access to a rigorous relativistic model of light ray propagation
developed in the framework of General Relativity. The data-processing of the
space interferometric observations must rely upon the theory of
general-relativistic transformations between the spacecraft, geocentric, and
solar barycentric reference systems allowing unique and unambiguous
interpretation of the stellar aberration and parallax effects. On the other
hand, the algorithm must also include physically adequate treatment of the
relativistic effect of light deflection caused by the spherically-symmetric
(monopole-dependent) part of the gravitational field of the Sun and planets as
well as the quadrupole- and spin-dependent counterparts of it. In some
particular cases the gravitomagnetic field induced by the translational motion
of the Sun and planets should be also taken into account for unambigious
prediction of the light-ray deflection angle. In the present paper we describe
the corresponding software program for taking into account all classical
(proper motion, parallax, etc.) and relativistic (aberration, deflection of
light) effects up to the microarcsecond threshold and demonstrate, using
numerical simulations, how observations of stars and/or quasars conducted on
board a space optical interferometer orbiting the Earth can be processed and
disentangled.

</DOC>
<DOC>
<DOCNO> 67750 </DOCNO>
Z' Bosons and Kaluza-Klein Excitations at Muon Colliders


  After an extremely brief overview of the discovery reach for Z' bosons, we
will discuss the physics of Kaluza-Klein(KK) excitations of the Standard Model
gauge bosons that can be explored by a high energy muon collider in the era
after the LHC and TeV Linear Collider. We demonstrate that the muon collider is
a necessary ingredient in the unraveling the properties of such KK states and,
perhaps, proving their existence.

</DOC>
<DOC>
<DOCNO> 85401 </DOCNO>
On Quantum Mechanics in Friedmann-Robertson-Walker Universe


  It is shown that only in the space-times admitting a 1+3-foliation by flat
Cauchy hypesurfaces (i.e., in the Bianchi I type space-times the isotropic
version of which the spatially flat Friedmann-Robertson-Walker space-times are)
the canonical quantization of geodesic motion and quantum-mechanics obtained as
an asymptotics of the quantum theory of scalar field lead to the same canonical
commutation relations (CCR). Otherwise, the field-theoretical approach leads to
a deformation of CCR (particularly, operators of coordinates do not commute),
and the Principle of Correspondence is broken in a sense. Thus, the spatially
flat cosmology is distinguished intrinsically in the quantum theory.

</DOC>
<DOC>
<DOCNO> 70243 </DOCNO>
Topology and metastability in the lattice Skyrme model


  We offer the Skyrme model on a lattice as an effective field theory - fully
quantized - of baryon-meson interactions at temperatures below the chiral phase
transition. We define a local topological density that involves the volumes of
tetrahedra in the target space S^3 and we make use of Coxeter's formula for the
Schlafli function to implement it. This permits us to calculate the mean-square
radius of a skyrmion in the three-dimensional lattice Skyrme model, which may
be viewed as a Ginzburg-Landau effective theory for the full quantum theory at
finite temperature. We find that, contrary to expectations, the skyrmion
shrinks as quantum and thermal fluctuations are enhanced. We ascribe this to a
large number of metastable states that become accessible as the temperature is
raised.

</DOC>
<DOC>
<DOCNO> 178773 </DOCNO>
The effective \omega-meson mass with a vector field self-interaction


  We calculate the effective mass m_\omega^* of the \omega-meson in nuclear
medium by the \sigma-\omega model with a vector field self-interaction (VFSI).
We found that the direct and the indirect effects of the VFSI almost cancel
each other and the result is changed only slightly at the normal density. The
VFSI makes m^*_\omega smaller at lower density and makes m_\omega^* larger at
higher density. However, both effects are not large.

</DOC>
<DOC>
<DOCNO> 12764 </DOCNO>
Quantum group invariant, nonextensive quantum statistical mechanics


  We study the consequences of introducing quantum group invariance in the
formalism of nonextensive quantum statistical mechanics.
 We find that the corresponding thermodynamical system is equivalent to a
Bose-Einstein gas in the Boltzmann-Gibbs formalism with a higher critical
temperature than the standard Bose-Einstein case.

</DOC>
<DOC>
<DOCNO> 117692 </DOCNO>
Design and expected performance of the ANTARES neutrino telescope


  The ANTARES Collaboration is aiming at the construction and the operation of
a large undersea neutrino telescope for neutrino astronomy, neutrino
oscillation and indirect dark matter searches. Started 3 years ago an intensive
R&D program has shown the feasibility of such a detector in the deep waters of
the Mediterranean sea. We have now started the design and the construction of a
0.1 km(^{2}) detector for which the expected performance will be briefly
described here.

</DOC>
<DOC>
<DOCNO> 68454 </DOCNO>
The b-u skewed parton distributions


  The b - u skewed parton distributions (SPDs) are discussed. The SPDs allow an
unambigous superposition of overlap and resonsance contributions and their
zeroth order moments represent the B - pi transition form factors. The values
of the form factors at maximum recoil are found to be F+(0)=F0(0)=0.22 with an
error of 0.05 in agreement with measurements of the B - pi pi branching ratio.
The branching ratios for the semi-leptonic B - pi decays are evaluated too.

</DOC>
<DOC>
<DOCNO> 150643 </DOCNO>
Massive Symmetric Space sine-Gordon Soliton Theories and Perturbed


  The perturbed conformal field theories corresponding to the massive Symmetric
Space sine-Gordon soliton theories are identified by calculating the central
charge of the unperturbed conformal field theory and the conformal dimension of
the perturbation. They are described by an action with a positive-definite
kinetic term and a real potential term bounded from below, their equations of
motion are non-abelian affine Toda equations and, moreover, they exhibit a mass
gap. The unperturbed CFT corresponding to the compact symmetric space G/G_0 is
either the WZNW action for G_0 or the gauged WZNW action for a coset of the
form G_0/U(1)^p. The quantum integrability of the theories that describe
perturbations of a WZNW action, named Split models, is established by showing
that they have quantum conserved quantities of spin +3 and -3. Together with
the already known results for the other massive theories associated with the
non-abelian affine Toda equations, the Homogeneous sine-Gordon theories, this
supports the conjecture that all the massive Symmetric Space sine-Gordon
theories will be quantum integrable and, hence, will admit a factorizable
S-matrix. The general features of the soliton spectrum are discussed, and some
explicit soliton solutions for the Split models are constructed. In general,
the solitons will carry both topological charges and abelian Noether charges.
Moreover, the spectrum is expected to include stable and unstable particles.

</DOC>
<DOC>
<DOCNO> 151367 </DOCNO>
Higgs Mechanism and Luna Strata in N=1 Gauge Theories


  The classical moduli space M of a supersymmetric gauge theory with trivial
superpotential can be stratified according to the unbroken gauge subgroup at
different vacua. We apply known results about this stratification to obtain the
W \neq 0 theory classical moduli space M^W \subset M, working entirely with the
composite gauge invariant operators X that span M, assuming we do not known
their elementary matter chiral field content. In this construction, the
patterns of gauge symmetry breaking of the W \neq 0 theory are determined,
Higgs flows in these theories show important differences from the W=0 case. The
methods here introduced provide an alternative way to construct tree level
superpotentials that lift all classical flat directions leaving a candidate
theory for dynamical supersymmetry breaking, and are also useful to identify
heavy composite fields to integrate out from effective superpotentials when the
elementary field content of the composites is unknown. We also show how to
recognize the massless singlets after Higgs mechanism at a vacuum X \in M^W
among the moduli \delta X using the stratification of M, and establish
conditions under which the space of non singlet massless fields after Higgs
mechanism (unseen as moduli \delta X) is null. A small set of theories with so
called "unstable" representations of the complexified gauge group is shown to
exhibit unexpected properties regarding the dimension of their moduli space,
and the presence of non singlet massless fields after Higgs mechanism at all of
their vacua.

</DOC>
<DOC>
<DOCNO> 121155 </DOCNO>
Tidally-induced angular momentum transport in disks


  We discuss the transport of angular momentum induced by tidal effects in a
disk surrounding a star in a pre-main sequence binary system. We consider the
effect of both density and bending waves. Although tidal effects are important
for truncating protostellar disks and for determining their size, it is
unlikely that tidally-induced angular momentum transport plays a dominant role
in the evolution of protostellar disks. Where the disk is magnetized, transport
of angular momentum is probably governed by MHD turbulence. In a non
self-gravitating laminar disk, the amount of transport provided by tidal waves
is probably too small to account for the lifetime of protostellar disks. In
addition, tidal effects tend to be localized in the disk outer regions.

</DOC>
<DOC>
<DOCNO> 102293 </DOCNO>
Three mathematical faces of SU(2) - spin networks


  Spin networks are at the core of quantum gravity. Our aim is to plug the
mathematical community at large into the procedures turn to create a finite
quantum theory of general relativity. For this, because of the different
cultural backgraund, we would like to change the tack: to relate discrete
(combinatorial) objects to the standard "contineous" geometry.

</DOC>
<DOC>
<DOCNO> 116391 </DOCNO>
Excitation of resonators by electron beams


  In this paper the main consequences of the vector theory of excitation of
resonators by particle beams are presented. Some features of excitation of
broadband radiation in longitudinal modes of the enclosed and open resonators
are discussed.

</DOC>
<DOC>
<DOCNO> 99483 </DOCNO>
Transversality theory, cobordisms, and invariants of symplectic


  This paper gives methods for understanding invariants of symplectic
quotients. The symplectic quotients considered here are compact symplectic
manifolds (or more generally orbifolds), which arise as the symplectic
quotients of a symplectic manifold by a compact torus. (A companion paper
examines symplectic quotients by a nonabelian group, showing how to reduce to
the maximal torus.)
  Let X be a symplectic manifold, with a Hamiltonian action of a compact torus
T. The main topological result of this paper describes an explicit cobordism
that exists between a symplectic quotient of X by T, and a collection of
iterated projective bundles over components of the set of T-fixed-points.
  The characteristic classes of these bundles can be determined explicitly, and
another result uses this to give formulae for integrals of cohomology classes
over the symplectic quotient, in terms of data localized at the T-fixed points
of X.

</DOC>
<DOC>
<DOCNO> 12519 </DOCNO>
Measurement of the energy dependence of phase relaxation by single


  Single electron tunneling through a single impurity level is used to probe
the fluctuations of the local density of states in the emitter. The energy
dependence of quasi-particle relaxation in the emitter can be extracted from
the damping of the fluctuations of the local density of states (LDOS). At
larger magnetic fields Zeeman splitting is observed.

</DOC>
<DOC>
<DOCNO> 10083 </DOCNO>
Anisotropic Compression in Dimer C60 Fullerene Solid


  Dimer C60 solids are monoclinic crystals with molecular longer axis aligned
along the c-axis. A simple model based on atom-atom potential used to calculate
various bulk, structural and thermodynamic properties of this fullerite, has
also been used to investigate the pressure and temperature dependent properties
such as bulk modulus, lattice and orientational structure, phonon dispersion
relations, Gruneisen parameters, heat capacity and entropy. An important
feature of this solid evidently concerns its anisotropic pressure compression.
We calculate these directional compressibilities and find the anisotropy for
pressure compression very significant. It is expected that the properties of
dimer solid C60 calculated here will motivate further experimentation on this
solid.

</DOC>
<DOC>
<DOCNO> 11072 </DOCNO>
Polarons in Carbon Nanotubes


  We use ab initio total-energy calculations to predict the existence of
polarons in semiconducting carbon nanotubes (CNTs). We find that the CNTs' band
edge energies vary linearly and the elastic energy increases quadratically with
both radial and with axial distortions, leading to the spontaneous formation of
polarons. Using a continuum model parametrized by the ab initio calculations,
we estimate electron and hole polaron lengths, energies and effective masses
and analyze their complex dependence on CNT geometry. Implications of polaron
effects on recently observed electro- and opto-mechanical behavior of CNTs are
discussed.

</DOC>
<DOC>
<DOCNO> 117604 </DOCNO>
CADIS deep star counts: Galactic structure and the stellar luminosity


  In this paper we present the first results of deep star counts carried out
within the Calar Alto Deep Imaging Survey, CADIS (Meisenheimer 1998). Although
CADIS was designed as an extragalactic survey, it also attempts to identify the
stars in the fields in order to avoid confusion with quasars and compact
galaxies. We have identified a sample of about 300 faint stars 15.5< R < 23),
which are well suited to study the structure of the Galaxy. The stars lie in
two fields, hereafter 16h and 9h field, respectively. The stars have been
separated from galaxies by a classification scheme based on photometric spectra
and morphological criteria. Distances were derived by photometric parallaxes.
We are able to find stars up to distances of approximately 25 kpc above the
Galactic plane. The vertical density distribution of the stars shows the
contribution of the thin disk, the stellar halo and the ``thick disk'' of the
Galaxy. We give quantitative descriptions of the components in terms of
exponential disks and a de Vaucouleurs spheroid. For the disk stars we derive
the luminosity function. It is equal within the errors to the local luminosity
function and continues to rise out to at least M_V = 13. Implications for the
mass function are briefly discussed.

</DOC>
<DOC>
<DOCNO> 83404 </DOCNO>
A Fuzzy Relational Identification Algorithm and Its Application to


  Fuzzy relational identification builds a relational model describing systems
behaviour by a nonlinear mapping between its variables. In this paper, we
propose a new fuzzy relational algorithm based on simplified max-min relational
equation. The algorithm presents an adaptation method applied to gravity-center
of each fuzzy set based on error integral value between measured and predicted
system output, and uses the concept of time-variant universe of discourses. The
identification algorithm also includes a method to attenuate noise influence in
extracted system relational model using a fuzzy filtering mechanism. The
algorithm is applied to one-step forward prediction of a simulated and
experimental motor drive system. The identified model has its input-output
variables (stator-reference current and motor speed signal) treated as fuzzy
sets, whereas the relations existing between them are described by means of a
matrix R defining the relational model extracted by the algorithm. The results
show the good potentialities of the algorithm in predict the behaviour of the
system and attenuate through the fuzzy filtering method possible noise
distortions in the relational model.

</DOC>
<DOC>
<DOCNO> 170760 </DOCNO>
Quantum factoring, discrete logarithms and the hidden subgroup problem


  Amongst the most remarkable successes of quantum computation are Shor's
efficient quantum algorithms for the computational tasks of integer
factorisation and the evaluation of discrete logarithms. In this article we
review the essential ingredients of these algorithms and draw out the unifying
generalization of the so-called abelian hidden subgroup problem. This involves
an unexpectedly harmonious alignment of the formalism of quantum physics with
the elegant mathematical theory of group representations and fourier transforms
on finite groups. Finally we consider the non-abelian hidden subgroup problem
mentioning some open questions where future quantum algorithms may be expected
to have a substantial impact.

</DOC>
<DOC>
<DOCNO> 12779 </DOCNO>
Perturbation expansion for 2-D Hubbard model


  We develop an efficient method to calculate the third-order corrections to
the self-energy of the hole-doped two-dimensional Hubbard model in space-time
representation. Using the Dyson equation we evaluate the renormalized spectral
function in various parts of the Brillouin zone and find significant
modifications with respect to the second-order theory even for rather small
values of the coupling constant U. The spectral function becomes unphysical for
$ U \simeq W $, where W is the half-width of the conduction band. Close to the
Fermi surface and for U<W, the single-particle spectral weight is reduced in a
finite energy interval around the Fermi energy. The increase of U opens a gap
between the occupied and unoccupied parts of the spectral function.

</DOC>
<DOC>
<DOCNO> 40594 </DOCNO>
Ultra-High Energy Neutrinos: A Review of Theoretical and


  We review the phenomenology of ultra-high energy (UHE) neutrino detection.
The motivations for looking for such neutrinos stemming from observational
evidence and the potential for new physics discoveries are enumerated, and
their expected sources and fluxes are given. Cross-sections with nucleons all
the way upto neutrino energies of 10^20 eV, and the attenuation of the fluxes
in the earth are discussed. Finally, sample event-rates for existing and future
Water/Ice Cerenkov detectors are provided.

</DOC>
<DOC>
<DOCNO> 102864 </DOCNO>
Stochastic differential equations for trace-class operators and quantum


  The theory of measurements continuous in time in quantum mechanics (quantum
continual measurements) has been formulated by using the notions of instrument
and positive operator valued measure, functional integrals, quantum stochastic
differential equations and classical stochastic differential equations (SDE's).
Various types of SDE's are involved, and precisely linear and non linear
equations for vectors in Hilbert spaces and for trace-class operators. All such
equations contain either a diffusive part, or a jump one, or both.
  In this paper we introduce a class of linear SDE's for trace-class operators,
relevant to the theory of continual measurements, and we recall how such SDE's
are related to instruments and master equations and, so, to the general
formulation of quantum mechanics. We do not present the Hilbert space
formulation of such SDE's and we make some mathematical simplifications: no
time dependence is introduced into the coefficients and only bounded operators
on the Hilbert space of the quantum system are considered. Then we introduce
the notion of a posteriori state and the non linear SDE satisfied by such
states and we give conditions from which such equation is assured to preserve
pure states and to send any mixed state into a pure one for large times.
Finally we review the known results about the existence and uniqueness of
invariant measures in the purely diffusive case and we give some concrete
examples of physical systems.

</DOC>
<DOC>
<DOCNO> 101780 </DOCNO>
Hodge-theoretic obstruction to existence of quaternion algebras


  The class in the Brauer group of a quaternion algebra over a field is
2-torsion. We study the following question: Which 2-torsion elements of the
Brauer group of a complex function field are representable by quaternion
algebras? Using intersection theory to show that a certain cohomology class (on
a smooth projective model) is the class of an algebraic cycle, we arrive at an
obstruction, defined on a subgroup of the 2-torsion of the Brauer group, to
representability by quaternion algebras. For the function fields of some
complex threefolds, the obstruction map is computed and found to be nontrivial.

</DOC>
<DOC>
<DOCNO> 122603 </DOCNO>
Inner disk oscillations


  The RXTE observations of GRS 1915+105 have given a new impulse to the study
of spectral and timing properties of the X-ray emission of black hole
candidates. At variance with any other known source, GRS 1915+105 shows
dramatic changes on time scales as short as a tenth of a second. These changes
are associated to marked spectral changes which have been interpreted as
changes of the observable inner radius of the accretion disk. I review the
existing results and discuss the current evidence for such disk oscillations.
Independently of the precise theoretical models, the detailed study of these
fast variations can provide an extremely valuable insight on the accretion
processes onto black holes. Making use of these results, I compare the
properties of GRS 1915+105 with those of other black hole

</DOC>
<DOC>
<DOCNO> 68068 </DOCNO>
Hadronization in the Chromodielectric Model


  We study the dynamics of quarks and gluons in the Chromodielectric Model
(CDM), which contains a dynamical description of confinement. Results are
presented for hadronization out of an equilibrated quark--gluon plasma. It is
shown that hadronization is complete and hadrons are classified within the
scheme of CDM.

</DOC>
<DOC>
<DOCNO> 152055 </DOCNO>
Rank 48 gauge group in heterotic string


  We discuss the existence of a non-perturbative gauge sector that can raise
the rank of the gauge group of the N_4=2 heterotic string up to 48. These gauge
bosons, that don't exist in six dimensions, co-exist with those originating
from small instantons shrinking to zero size.

</DOC>
<DOC>
<DOCNO> 84753 </DOCNO>
Causal Boundary Entropy From Horizon Conformal Field Theory


  The quantum theory of near horizon regions of spacetimes with classical
spatially flat, homogeneous and isotropic Friedman-Robertson-Walker geometry
can be approximately described by a two dimensional conformal field theory. The
central charge of this theory and expectation value of its Hamiltonian are both
proportional to the horizon area in units of Newton's constant. The statistical
entropy of horizon states, which can be calculated using two dimensional state
counting methods, is proportional to the horizon area and depends on a
numerical constant of order unity which is determined by Planck scale physics.
This constant can be fixed such that the entropy is equal to a quarter of the
horizon area in units of Newton's constant, in agreement with thermodynamic
considerations.

</DOC>
<DOC>
<DOCNO> 119816 </DOCNO>
Gas in Galaxies


  The interstellar medium (ISM) can be thought of as the galactic atmosphere
which fills the space between stars. When clouds within the ISM collapse, stars
are born. When the stars die, they return their matter to the surrounding gas.
Therefore the ISM plays a vital role in galactic evolution. The medium includes
starlight, gas, dust, planets, comets, asteroids, fast moving charged particles
(cosmic rays) and magnetic fields. The gas can be further divided into hot,
warm and cold components, each of which appear to exist over a range of
densities, and therefore pressures. Remarkably, the diverse gas components,
cosmic rays, magnetic fields and starlight all have very roughly the same
energy density of about 1 eV cm$^{-3}$. All the major constituents (or phases)
of the interstellar medium appear to be identified now, although complete
multi-phase studies are extremely difficult beyond a few thousand parsecs from
the Sun. The interstellar medium is a highly complex environment which does not
lend itself to simple analysis. However, this has not stopped astrophysicists
from producing basic models of the ISM in order to make sense of the great
wealth of data coming in from ground-based telescopes and from satellites.

</DOC>
<DOC>
<DOCNO> 7866 </DOCNO>
Realistic simulations of Au(100): Grand Canonical Monte Carlo and


  The large surface density changes associated with the (100) noble metals
surface hex-reconstruction suggest the use of non-particle conserving
simulation methods. We present an example of a surface Grand Canonical Monte
Carlo applied to the transformation of a square non reconstructed surface to
the hexagonally covered low temperature stable Au(100). On the other hand,
classical Molecular Dynamics allows to investigate microscopic details of the
reconstruction dynamics, and we show, as an example, retraction of a step and
its interplay with the surface reconstruction/deconstruction mechanism.

</DOC>
<DOC>
<DOCNO> 119222 </DOCNO>
The Effect of the Cosmic Web on Cluster Weak Lensing Mass Estimates


  In modern hierarchical theories of structure formation, rich clusters of
galaxies form at the vertices of a weblike distribution of matter, with
filaments emanating from them to large distances and with smaller objects
forming and draining in along these filaments. The amount of mass contained in
structure near the cluster can be comparable to the collapsed mass of the
cluster itself. As the lensing kernel is quite broad along the line of sight
around cluster lenses with typical redshifts near z=0.5, structures many Mpc
away from the cluster are essentially at the same location as the cluster
itself, when considering their effect on the cluster's weak lensing signal. We
use large-scale numerical simulations of structure formation in a
Lambda-dominated cold dark matter model to quantify the effect that large-scale
structure near clusters has upon the cluster masses deduced from weak lensing
analysis. A correction for the scatter in possible observed lensing masses
should be included when interpreting mass functions from weak lensing surveys.

</DOC>
<DOC>
<DOCNO> 122159 </DOCNO>
Simulations of galaxy formation in a cosmological volume


  We present results of large N-body-hydrodynamic simulations of galaxy
formation. Our simulations follow the formation of galaxies in cubic volumes of
side 100Mpc, in two versions of the cold dark matter (CDM) cosmogony: the
standard, Omega=1 SCDM model and the flat, Omega=0.3 LCDM model. Over 2000
galaxies form in each of these simulations. We examine the rate at which gas
cools and condenses into dark matter halos. This roughly tracks the cosmic star
formation rate inferred from observations at various redshifts. Galaxies in the
simulations form gradually over time in the hierarchical fashion characteristic
of the CDM cosmogony. In the LCDM model, substantial galaxies first appear at
z=5 and the population builds up rapidly until z=1 after which the rate of
galaxy formation declines as cold gas is consumed and the cooling time of hot
gas increases. In both cosmologies, the present-day K-band luminosity function
of the simulated galaxies resembles observations. The galaxy autocorrelation
functions differ significantly from those of the dark matter. At the present
epoch there is little bias in either model between galaxies and dark matter on
large scales, but a significant anti-bias on scales of 1Mpc/h and a positive
bias on scales of 100kpc/h. The galaxy correlation function evolves little with
redshift in the range z=0-3, and depends on the luminosity of the galaxy
sample. The projected pairwise velocity dispersion of the galaxies is much
lower than that of the dark matter on scales less than 2Mpc/h. Applying a
virial mass estimator to the largest galaxy clusters recovers the cluster
virial masses in an unbiased way. (Abridged)

</DOC>
<DOC>
<DOCNO> 69446 </DOCNO>
Back reaction of a long range force on a Friedmann-Robertson-Walker


  It is possible that there may exist long-range forces in addition to gravity.
In this paper we construct a simple model for such a force based on exchange of
a massless scalar field and analyze its effect on the evolution of a
homogeneous Friedmann-Robertson-Walker cosmology. The presence of such an
interaction leads to an equation of state characterized by positive pressure
and to resonant particle production similar to that observed in preheating
scenarios.

</DOC>
<DOC>
<DOCNO> 70387 </DOCNO>
Twin Peaks


  The on-shell imaginary part of the retarded selfenergy of massive $\vr^4$
theory in 1+1 dimensions is logarithmically infrared divergent. This leads to a
zero in the spectral function, separating its usual bump into two. The twin
peaks interfere in time-dependent correlation functions, which causes
oscillating modulations on top of exponential-like decay, while the usual
formulas for the decay rate fail. We see similar modulations in our numerical
results for a mean field correlator, using a Hartree ensemble approximation.

</DOC>
<DOC>
<DOCNO> 150554 </DOCNO>
Wilson lines on noncommutative tori


  We introduce the notion of a monodromy for gauge fields with vanishing
curvature on the noncommutative torus. Similar to the ordinary gauge theory,
traces of the monodromies define noncommutative Wilson lines. Our main result
is that these Wilson lines are invariant under the Seiberg-Witten map changing
the deformation parameter of the noncommutative torus.

</DOC>
<DOC>
<DOCNO> 40548 </DOCNO>
A Quasi-Model-Independent Search for New Physics at Large Transverse


  We apply a quasi-model-independent strategy ("Sleuth") to search for new high
p_T physics in approximately 100 pb^-1 of ppbar collisions at sqrt(s) = 1.8 TeV
collected by the DZero experiment during 1992-1996 at the Fermilab Tevatron.
Over thirty-two e mu X, W+jets-like, Z+jets-like, and 3(lepton/photon)X
exclusive final states are systematically analyzed for hints of physics beyond
the standard model. Simultaneous sensitivity to a variety of models predicting
new phenomena at the electroweak scale is demonstrated by testing the method on
a particular signature in each set of final states. No evidence of new high p_T
physics is observed in the course of this search, and we find that 89% of an
ensemble of hypothetical similar experimental runs would have produced a final
state with a candidate signal more interesting than the most interesting
observed in these data.

</DOC>
<DOC>
<DOCNO> 71584 </DOCNO>
Weak decays of pseudo Goldstone bosons


  A short overview of recent progress in describing kaon and pion decays within
Chiral Perturbation Theory is presented. Particular attention is devoted to the
issues of final-state interactions and isospin breaking in $K \to 2 \pi$, as
well as to the estimate of long-distance contributions in $K \to \ell^+\ell^-
(\pi)$.

</DOC>
<DOC>
<DOCNO> 120473 </DOCNO>
Coherent radio emission from the magnetic chemically peculiar star CU


  Radio observations of the magnetic chemically peculiar star CU Vir, carried
out with the VLA in three different days, show that the radio emission at 20 cm
is characterized by a strong enhancement at particular rotational phases. This
radio emission is found to be right hand polarized with a degree of
polarization close to 100 %. As common for this class of stars, the magnetic
axis of CU Vir is oblique with respect to the rotational axis. By comparing the
20 cm radio light curve with the effective magnetic field available from the
literature, a coincidence of the main peaks of the radio emission with the
magnetic nulls has been found. This happens when the magnetic axis lies in the
plane of the sky. We suggest that the high degree of polarization, together
with the high directivity of the radiation, can be explained in terms of
coherent radio emission. The data have been interpreted on the basis of the
Electron Cyclotron Maser Emission from electrons accelerated in current sheets
out of the Alfven radius toward the stellar surface and eventually reflected
outward by magnetic mirroring.

</DOC>
<DOC>
<DOCNO> 99753 </DOCNO>
On q-Deformations of Clifford Algebras


  Several Clifford algebras that are covariant under the action of a Lie
algebra $g$ can be deformed in a way consistent with the deformation of $Ug$
into a quantum group (or into a triangular Hopf algebra) $U_qg$, i.e. so as to
remain covariant under the action of $U_qg$. In this report, after recalling
these facts, we review our results regarding the formal realization of the
elements of such ``q-deformed'' Clifford algebras as ``functions''
(polynomials) in the generators of the undeformed ones; in particular, the
intruiging interplay between the original and the q-deformed symmetry. Finally,
we briefly illustrate their dramatic consequences on the representation
theories of the original and of the q-deformed Clifford algebra, and mention
how these results could turn out to be useful in quantum physics.

</DOC>
<DOC>
<DOCNO> 150826 </DOCNO>
Thermodynamics of the Complex su(3) Toda Theory


  We present the first computation of the thermodynamic properties of the
complex su(3) Toda theory. This is possible thanks to a new string hypothesis,
which involves bound states that are non self-conjugate solutions of the Bethe
equations. Our method provides equivalently the solution of the su(3)
generalization of the XXZ chain. In the repulsive regime, we confirm that the
scattering theory proposed over the past few years - made only of solitons with
non diagonal S-matrices - is complete. But we show that unitarity does not
follow, contrary to early claims, eigenvalues of the monodromy matrix not being
pure phases. In the attractive regime, we find that the proposed minimal
solution of the bootstrap equations is actually far from being complete. We
discuss some simple values of the couplings, where, instead of the few
conjectured breathers, a very complex structure (involving E_6, or two E_8) of
bound states is necessary to close the bootstrap.

</DOC>
<DOC>
<DOCNO> 40179 </DOCNO>
Development of rf reference line for the linear collider


  The rf distribution system for the linear collider requires stable
x-band(11.424GHz) rf phase signal over 25km length. In order to realize the
distribution system, a fiber optic link using a phase stabilized optical fiber
was tested. The phase stabilized optical fiber has been employed at LEP, KEKB,
etc.. This paper describes the hardware system and result of the preliminary
test of the feed back system for stabilization of the phase change.

</DOC>
<DOC>
<DOCNO> 121267 </DOCNO>
Interstellar Gas and Star Formation Near the Peculiar Radio Galaxy NGC


  We present new multi-wavelength data for the NGC 4410 galaxy group. This
group contains the peculiar radio galaxy NGC 4410A, which has a distorted
double-lobed radio structure. NGC 4410A is strongly interacting with three
nearby galaxies, and has a peculiar ring-like optical morphology, a number of
luminous H II regions, as well as as tidal tails and bridges variously visible
in optical, HI, and X-ray light. The gravitational interaction has affected the
interstellar matter, the star formation rate, and the radio lobes in this
system.

</DOC>
<DOC>
<DOCNO> 121950 </DOCNO>
X-ray Spectroscopy of the Cluster of Galaxies Abell 1795 with XMM-Newton


  The initial results from XMM-Newton observations of the rich cluster of
galaxies Abell 1795 are presented. The spatially-resolved X-ray spectra taken
by the European Photon Imaging Cameras (EPIC) show a temperature drop at a
radius of $\sim 200$ kpc from the cluster center, indicating that the ICM is
cooling. Both the EPIC and the Reflection Grating Spectrometers (RGS) spectra
extracted from the cluster center can be described by an isothermal model with
a temperature of $\sim 4$ keV. The volume emission measure of any cool
component ($<1$ keV) is less than a few % of the hot component at the cluster
center. A strong OVIII Lyman-alpha line was detected with the RGS from the
cluster core. The O abundance and its ratio to Fe at the cluster center is
0.2--0.5 and 0.5--1.5 times the solar value, respectively.

</DOC>
<DOC>
<DOCNO> 12340 </DOCNO>
Surface and bulk critical behaviour of the XY chain in a transverse


  The surface magnetization of the quantum XY chain in a transverse field is
found for arbitrary nearest neighbour interactions in closed form. This allows
to derive the bulk phase diagram in a simple way. The magnetic surface
behaviour and the bulk correlation length are found exactly.

</DOC>
<DOC>
<DOCNO> 84109 </DOCNO>
Cosmological Constant, Quintessence and Scalar-Tensor Theories of


  We show how the scalar field, a candidate of quintessence, in a proposed
model of the scalar-tensor theories of gravity provides a way to understand a
small but nonzero cosmological constant as indicated by recent observations. A
particular emphasis is placed on the effort to inherit the success of the
scenario of a decaying cosmological constant. Discussions of a possible link to
non-Newtonian gravity, the coincidence problem, the issue of time-variability
of coupling constants as well as the chaos-like nature of the solution are also
included in a new perspective.

</DOC>
<DOC>
<DOCNO> 119197 </DOCNO>
A Finding List for Delta_mu Binaries derived from a Comparison of


  The comparison of quasi-instantaneously measured HIPPARCOS proper motions
with long-term averaged proper motions, derived from ground-based data, allows
the identification of many stellar objects as Delta_mu binaries (Wielen et al.,
1999, A&A 346, 675). We have used this method to find Delta_mu binaries among
the fundamental stars, among the GC stars, and among the Tycho-2 stars. A
finding list for about 4000 Delta_mu binaries is given under the URL
http://www.ari.uni-heidelberg.de/dmubin in a machine-readable format. This
information on the probable duplicity of the listed objects can be used for
planning specific observing programs, for improving our knowledge of binary
statistics, or for avoiding the use of these binaries in some astrophysical
calibrations or as astrometric reference stars.

</DOC>
<DOC>
<DOCNO> 151614 </DOCNO>
Casimir effect for scalar fields under Robin boundary conditions on


  We study the Casimir effect for scalar fields with general curvature coupling
subject to mixed boundary conditions $(1+\beta_{m}n^{\mu}\partial_{\mu})\phi
=0$ at $x=a_{m}$ on one ($m=1$) and two ($m=1,2$) parallel plates at a distance
$a\equiv a_{2}-a_{1}$ from each other. Making use of the generalized Abel-Plana
formula previously established by one of the authors \cite{Sahrev}, the Casimir
energy densities are obtained as functions of $\beta_{1}$ and of
$\beta_{1}$,$\beta_{2}$,$a$, respectively. In the case of two parallel plates,
a decomposition of the total Casimir energy into volumic and superficial
contributions is provided. The possibility of finding a vanishing energy for
particular parameter choices is shown, and the existence of a minimum to the
surface part is also observed. We show that there is a region in the space of
parameters defining the boundary conditions in which the Casimir forces are
repulsive for small distances and attractive for large distances. This yields
to an interesting possibility for stabilizing the distance between the plates
by using the vacuum forces.

</DOC>
<DOC>
<DOCNO> 120498 </DOCNO>
Proper Motions of Pre-Main Sequence Stars in Southern Star-Forming


  We present proper motion measurements of pre-main sequence (PMS) stars
associated with major star-forming regions of the southern hemisphere
(Chamaeleon, Lupus, Upper Scorpius - Ophiuchus, Corona Australis), situated in
the galactic longitude range l = 290\degr to l = 360\degr. A list of PMS stars
as complete as possible was established based on the Herbig and Bell catalogue
and many new catalogues like the PDS survey, the catalogue of Herbig Ae/Be
stars by Th\'e et al. (1994), X-rays surveys, etc. The measurements made use of
public material (mainly AC2000 and USNO--A2.0 catalogues) as well as scans of
SERC-J Schmidt plates with the MAMA measuring machine (Paris) and Valinhos CCD
meridian circle observations (Brazil). We derived proper motions for 214 stars,
with an accuracy of 5 to 10 mas/yr depending mainly on the difference of epochs
between the position sources. The main characteristics of the sample are
discussed. We show that systematic motions of groups of stars exist, which are
not explained by the reflex solar motion.

</DOC>
<DOC>
<DOCNO> 12244 </DOCNO>
Magnetotunneling in a Two-Dimensional Electron-Hole System Near


  We have measured the zero-bias differential tunneling conductance of
InAs/AlSb/GaS b/AlSb/InAs heterostructures at low temperatures (1.7K < T < 60K)
and unde r a magnetic field at various angles with the heterostructure's
interfaces. Shubni kov-de Haas oscillations in the magnetoconductance reveal
the two-dimensional (2D) character of the electrons accumulated at the InAs
interfaces and yield their num ber in each of them. The temperature dependence
of the oscillations suggests the f ormation of a field-induced energy gap at
the Fermi level, similar to that observe d before in simpler 2D-2D tunneling
systems. A calculation of the magnetoconductan ce that considers different 2D
densities in the two InAs electrodes agrees with th e main observations, but
fails to explain features that might be related to the pr esence of 2D holes in
the GaSb region.

</DOC>
<DOC>
<DOCNO> 10630 </DOCNO>
Finite-size-scaling analyses of the chiral order in the


  Chiral order of the Josephson-junction ladder with half a flux quantum per
plaquette is studied by means of the exact diagonalization method. We consider
an extreme quantum limit where each superconductor grain (order parameter) is
represented by S=1/2 spin. So far, the semi-classical S -> \infty case, where
each spin reduces to a plane rotator, has been considered extensively. We found
that in the case of S=1/2, owing to the strong quantum fluctuations, the chiral
(vortex lattice) order becomes dissolved except in a region, where attractive
intrachain and, to our surprise, repulsive interchain interactions both exist.
On the contrary, for considerably wide range of parameters, the superconductor
(XY) order is kept critical. The present results are regarded as a
demonstration of the critical phase accompanying chiral-symmetry breaking
predicted for frustrated XXZ chain field-theoretically.

</DOC>
<DOC>
<DOCNO> 70197 </DOCNO>
High Energy Nucleus-Nucleus Collisions In View Of The Multi-Peripheral


  The hypothesis of the multi peripheral model is extended to the
hadron-nucleus interactions and then generalized to the nucleus-nucleus case.
The processing of the model depends on input parameters that are extracted from
the features of the experiments in this field. The number of encountered
nucleons from both target and projectile are estimated according to the eikonal
scattering approach. The screening effect due to the interaction of the
projectile nucleons in successive manner with the target nucleus is considered.
The rapidity distributions of fast particles are reproduced for the successive
collisions in p-S and $^{32}$S-$^{32}$S interactions at 200 A GeV. A global
fair agreement is found in comparison with data of the experiment SLAC-NA-035.

</DOC>
<DOC>
<DOCNO> 70160 </DOCNO>
Baryon Transport in Dual Models and the Possibility of a Backward Peak


  We begin to briefly survey the experimental and conceptual side of baryon
transfers in particle scattering. A discussion of baryon transfers in heavy ion
scattering follows. It shortly reviews existing string model concepts, which
were found to be consistent with the data. With this motivation we turn to a
more careful consideration of the relevant topological structures. The baryon
transfer is associated with one of two possible cuts in baryonium exchange.
  From the color structure the baryonium can be identified with an Odderon
exchange. We conjecture that the two Odderon cuts occur with an opposite sign
and partially cancel. As the Odderon is predicted to have a rather high
trajectory it has to involve small coupling constants. As this suppression is
not anticipated for diffractive processes a tiny observable backward peak is
argued to occur in the initial baryon distribution in massive diffractive
systems.

</DOC>
<DOC>
<DOCNO> 13002 </DOCNO>
Ergodicity and the Classical Lambda Phi^4 Lattice Field Theory


  In this talk we present some studies in the approach to equilibrium of the
classical lambda phi^4 theory on the lattice, giving particular emphasis to its
pedagogical usefulness in the context of classical statistical field theory
(such as both the analytical and numerical evaluation of correlation
functions), as well as in the context of statistical mechanics (such as the
equivalence of ensembles in the thermodynamic limit). Since the quartic term
could be regarded as a smooth perturbation to the (integrable) gaussian theory,
we also discuss the connection of our results with the KAM theorem, showing
that the ergodic and non-ergodic regimes are not sharply separated.

</DOC>
<DOC>
<DOCNO> 119756 </DOCNO>
Multi-Read Out Data Simulator


  We present a data simulation package designed to create a series of simulated
data samples for a detector with non-destructive sampling capability. The
original intent of this software was to provide a method for generating
simulated images for the Next Generation Space Telescope, but it is general
enough to apply to almost any non-destructive detector or instrument.
MultiDataSim can be used to generate "practice" sampling strategies for an
instrument or field-of-view, and thus can be used to identify optimal
observation strategies.

</DOC>
<DOC>
<DOCNO> 116680 </DOCNO>
Nonzero angular momentum states of the helium atom in a strong magnetic


  The electronic structure of the helium atom in the magnetic field regime
B=0-100a.u. is investigated, using a full configuration interaction approach
which is based on a nonlinearly optimized anisotropic Gaussian basis set of
one-particle functions. The corresponding generalized eigenvalue problem is
solved for the magnetic quantum number M=-1 and for both even and odd z-parity
as well as singlet and triplet spin symmetry. Accurate total electronic
energies of the ground state and the first four excitations in each subspace as
well as their one-electron ionization energies are presented as a function of
the magnetic field. Additionally we present energies for electromagnetic
transitions within the M=-1 subspace and between the M=-1 subspace and the M=0
subspace treated in a previous work. A complete table of wavelengths and field
strengths for the detected stationary points is given.

</DOC>
<DOC>
<DOCNO> 80771 </DOCNO>
Quenched Lattice QCD with Domain Wall Fermions and the Chiral Limit


  Quenched QCD simulations on three volumes, $8^3 \times$, $12^3 \times$ and
$16^3 \times 32$ and three couplings, $\beta=5.7$, 5.85 and 6.0 using domain
wall fermions provide a consistent picture of quenched QCD. We demonstrate that
the small induced effects of chiral symmetry breaking inherent in this
formulation can be described by a residual mass ($\mres$) whose size decreases
as the separation between the domain walls ($L_s$) is increased. However, at
stronger couplings much larger values of $L_s$ are required to achieve a given
physical value of $\mres$. For $\beta=6.0$ and $L_s=16$, we find
$\mres/m_s=0.033(3)$, while for $\beta=5.7$, and $L_s=48$,
$\mres/m_s=0.074(5)$, where $m_s$ is the strange quark mass. These values are
significantly smaller than those obtained from a more naive determination in
our earlier studies. Important effects of topological near zero modes which
should afflict an accurate quenched calculation are easily visible in both the
chiral condensate and the pion propagator. These effects can be controlled by
working at an appropriately large volume. A non-linear behavior of $m_\pi^2$ in
the limit of small quark mass suggests the presence of additional infrared
subtlety in the quenched approximation. Good scaling is seen both in masses and
in $f_\pi$ over our entire range, with inverse lattice spacing varying between
1 and 2 GeV.

</DOC>
<DOC>
<DOCNO> 121201 </DOCNO>
Radio-Quiet Quasars in the Direction of the Northern Hubble Deep Field


  We match quasars discovered in a multi-color survey centered on the northern
Hubble Deep Field (HDF) with radio sources from an ultra-deep radio survey.
Although 3 out of 12 quasars are detected at a level below 0.2 mJy at 1.4 GHz,
all of the quasars in the search area are radio-quiet by the criterion L_r <
10^{25} h^{-1}_{50} W/Hz. We combine this information with other radio surveys
of quasars so as to break the degeneracy between redshift and luminosity. In
the redshift range 0.02 < z < 3.64, the radio-loud fraction increases with
increasing optical luminosity, consistent with some degree of correlation
between the non-thermal optical and radio emissions. More tentatively, for low
luminosity quasars in the range -22.5 < M_B < -25, the radio-loud fraction
decreases with increasing redshift. We can infer from this that the radio
luminosity function evolves more slowly than the optical luminosity function.
The mechanism that leads to strong radio emission in only a small fraction of
quasars at any epoch is still unknown.

</DOC>
<DOC>
<DOCNO> 8578 </DOCNO>
Renormalization group in Statistical Mechanics and Mechanics: gauge


  Two very different problems that can be studied by renormalization group
methods are discussed with the aim of showing the conceptual unity that
renormalization group has introduced in some areas of theoretical Physics. The
two problems are: the ground state theory of a one dimensional quantum Fermi
liquid and the existence of quasi periodic motions in classical mechanical
systems close to integrable ones. I summarize here the main ideas and show that
the two treatments, although completely independent of each other, are
strikingly similar.

</DOC>
<DOC>
<DOCNO> 170574 </DOCNO>
The importance of quantum decoherence in brain processes


  It is shown how environmental decoherence plays an essential and constructive
role in a quantum mechanical theory of brain process that has significant
explanatory power.

</DOC>
<DOC>
<DOCNO> 122422 </DOCNO>
Enhanced black hole formation by multiple winding cosmic strings


  Primordial black hole formation by cosmic string collapse is reconsidered
when the winding number of the string is larger than the unity. The line energy
density of the multiple winding string becomes greater than that of the single
winding string so that the probability of the black hole formation by the
string collapse during the loop oscillation would be strongly enhanced.
Although the production of the multiple winding defect is suppressed and its
number density should be small, the enhancement of the black hole formation by
the increased energy density may provide a large number of evaporating black
holes in the present universe which gives more stringent constraint on the
string model compared to the ordinary string scenario.

</DOC>
<DOC>
<DOCNO> 121540 </DOCNO>
Molecular Gas in Elliptical Galaxies


  The distribution and kinematics of the molecular gas in elliptical galaxies
give information on the origin and history of the gas and the rate of star
formation activity in ellipticals. I describe some preliminary results of a
survey which will more than double the number of elliptical galaxies with
resolved molecular distributions.

</DOC>
<DOC>
<DOCNO> 9838 </DOCNO>
Evolution of interfaces and expansion in width


  Interfaces in a model with a single, real nonconserved order parameter and
purely dissipative evolution equation are considered. We show that a systematic
perturbative approach, called the expansion in width and developed for curved
domain walls, can be generalized to the interfaces. Procedure for calculating
curvature corrections is described. We also derive formulas for local velocity
and local surface tension of the interface. As an example, evolution of
spherical interfaces is discussed, including an estimate of critical size of
small droplets.

</DOC>
<DOC>
<DOCNO> 8164 </DOCNO>
Control of Squeezed States


  In this paper we consider the classical and quantum control of squeezed
states of harmonic oscillators. This provides a method for reducing noise below
the quantum limit and provides an example of the control of under-actuated
systems in the stochastic and quantum context. We consider also the interaction
of a squeezed quantum oscillator with an external heat bath.

</DOC>
<DOC>
<DOCNO> 70364 </DOCNO>
Radion Mediated Supersymmetry Breaking


  We point out that in supersymmetric theories with extra dimensions, radius
stabilization can give rise to a VEV for the $F$ component of the radius
modulus. This gives an important contribution to supersymmetry breaking of
fields that propagate in the bulk. A particularly attractive class of models is
obtained if the standard-model gauge fields propagate in the bulk, while the
quark and lepton fields are localized on a brane. This leads to gaugino
mediated supersymmetry breaking without the need for singlets in the hidden
sector. We analyze a simple explicit model in which this idea is realized.

</DOC>
<DOC>
<DOCNO> 150460 </DOCNO>
String Loop Threshold Corrections for N=1 Generalized Coxeter Orbifolds


  We discuss the calculation of threshold corrections to gauge coupling
constants for the, only, non-decomposable class of abelian (2, 2) symmetric N=1
four dimensional heterotic orbifold models, where the internal twist is
realized as a generalized Coxeter automorphism. The latter orbifold was singled
out in earlier work as the only N=1 heterotic $Z_N$ orbifold that satisfy the
phenomenological criteria of correct minimal gauge coupling unification and
cancellation of target space modular anomalies.

</DOC>
<DOC>
<DOCNO> 84924 </DOCNO>
Solution of Dirac equation around a spinning Black Hole


  Chandrasekhar separated the Dirac equation for spinning and massive particles
in Kerr geometry in radial and angular parts. Chakrabarti solved the angular
equation and found the corresponding eigenvalues for different Kerr parameters.
The radial equations were solved asymptotically by Chandrasekhar. In the
present paper, we use the WKB approximation to solve the spatially complete
radial equation and calculate analytical expressions of radial wave functions
for a set of Kerr and wave parameters. From these solutions we obtain local
values of reflection and transmission coefficients.

</DOC>
<DOC>
<DOCNO> 150620 </DOCNO>
Free Large N Supersymmetric Yang-Mills Theory as a String Theory


  The strong version of Maldacena's AdS/CFT conjecture implies that the large N
expansion of free N=4 super-YM theory describes an interacting string theory in
the extreme limit of high spacetime curvature relative to the string length.
String states may then be understood as composed of SYM string bits. We
investigate part of the low-lying spectrum of the tensionless (zero-coupling)
limit and find a large number of states that are not present in the infinite
tension (strong-coupling) limit, notably several massless spin two particles.
We observe that all conformal dimensions are N-independent in the free SYM
theory, implying that masses in the corresponding string theory are unchanged
by string interactions. Degenerate string states do however mix in the
interacting string theory because of the complicated N-dependence of general
CFT two-point functions. Finally we verify the CFT crossing symmetry, which
corresponds to the dual properties of string scattering amplitudes. This means
that the SYM operator correlation functions define AdS dual models analogous to
the Minkowski dual models that gave rise to string theory.

</DOC>
<DOC>
<DOCNO> 8059 </DOCNO>
The critical equation of state of three-dimensional XY systems


  We address the problem of determining the critical equation of state of
three-dimensional XY systems. For this purpose we first consider the
small-field expansion of the effective potential (Helmholtz free energy) in the
high-temperature phase. We compute the first few nontrivial zero-momentum
n-point renormalized couplings, which parametrize such expansion, by analyzing
the high-temperature expansion of an improved lattice Hamiltonian with
suppressed leading scaling corrections.
  These results are then used to construct parametric representations of the
critical equation of state which are valid in the whole critical regime,
satisfy the correct analytic properties (Griffith's analyticity), and take into
account the Goldstone singularities at the coexistence curve. A systematic
approximation scheme is introduced, which is limited essentially by the number
of known terms in the small-field expansion of the effective potential.
  From our approximate representations of the equation of state, we derive
estimates of universal ratios of amplitudes. For the specific-heat amplitude
ratio we obtain A^+/A^-=1.055(3), to be compared with the best experimental
estimate A^+/A^-=1.054(1).

</DOC>
<DOC>
<DOCNO> 13114 </DOCNO>
Surface melting of methane and methane film on magnesium oxide


  Experiments on surface melting of several organic materials have shown
contradictory results. We study the Van der Waals interactions between
interfaces in surface melting of the bulk CH_4 and interfacial melting of the
CH_4 film on the MgO substrate. This analysis is based on the theory of
Dzyaloshinskii, Lifshitz, and Pitaevskii for dispersion forces in materials
characterized by the frequency dependent dielectric functions. These functions
for magnesium oxide and methane are obtained from optical data using an
oscillator model of the dielectric response. The results show that a repulsive
interaction between the solid-liquid and liquid-vapor interfaces exists for the
bulk methane. We also found that the van der Waals forces between two
solid-liquid interfaces are attractive for the CH_4 film on the MgO substrate.
This implies that the van der Waals forces induce the presence of complete
surface melting for the bulk methane and the absence of interfacial melting for
CH_4 on the MgO substrate.

</DOC>
<DOC>
<DOCNO> 84922 </DOCNO>
Satellite gravitational orbital perturbations and the gravitomagnetic


  In order to detect the gravitomagnetic clock effect by means of two
counter-orbiting satellites placed on identical equatorial and circular orbits
around the Earth with radius 7000 km their radial and azimuthal positions must
be known with an accuracy of delta r =10^{-1} mm and delta phi =10^{-2} mas per
revolution. In this work we investigate if the radial and azimuthal
perturbations induced by the dynamical and static parts of the Earth' s
gravitational field meet this requirements. While the radial direction is
affected only by harmonic perturbations with periods up to some tens of days,
the azimuthal location is perturbed by a secular drift and very long period
effects.It results that the present level of accuracy in the knowledge both of
the Earth solid and ocean tides, and of the static part of the geopotential
does not allow an easy detection of the gravitomagnetic clock effect, at least
by using short arcs only.

</DOC>
<DOC>
<DOCNO> 11273 </DOCNO>
Kinetics of Surfactant Adsorption: The Free Energy Approach


  We review the free energy approach to the kinetics of surfactant adsorption
at fluid/fluid interfaces. The formalism is applied to several systems. For
non-ionic surfactant solutions the results coincide with previous models while
indicating their limits of validity. We study the case of surfactant mixtures,
focusing on the relation between the mixture kinetics and the properties of its
individual constituents. Strong electrostatic interactions in salt-free ionic
surfactant solutions drastically modify the adsorption kinetics. In this case
the theory accounts for experimental results which could not be previously
understood. The effect of screening by added salt is studied as well. Our
theoretical predictions are compared with available experiments.

</DOC>
<DOC>
<DOCNO> 9006 </DOCNO>
Harvesting Thermal Fluctuations: Activation Process Induced by a


  We present a model in which the immediate environment of a bistable system is
a molecular chain which in turn is connected to a thermal environment of the
Langevin form. The molecular chain consists of masses connected by harmonic or
by anharmonic springs. The distribution, intensity, and mobility of thermal
fluctuations in these chains is strongly dependent on the nature of the springs
and leads to different transition dynamics for the activated process. Thus, all
else (temperature, damping, coupling parameters between the chain and the
bistable system) being the same, the hard chain may provide an environment
described as diffusion-limited and more effective in the activation process,
while the soft chain may provide an environment described as energy-limited and
less effective. The importance of a detailed understanding of the thermal
environment toward the understanding of the activation process itself is thus
highlighted.

</DOC>
<DOC>
<DOCNO> 40469 </DOCNO>
Recent results from the canfranc dark matter search with germanium


  Two germanium detectors are currently operating in the Canfranc Underground
Laboratory at 2450 m.w.e looking for WIMP dark matter. One is a 2 kg 76Ge IGEX
detector (RG-2) which has an energy threshold of 4 keV and a low-energy
background rate of about 0.3 c/keV/kg/day. The other is a small (234 g) natural
abundance Ge detector (COSME), of low energy threshold (2.5 keV) and an energy
resolution of 0.4 keV at 10 keV which is looking for WIMPs and for solar
axions. The analysis of 73 kg-days of data taken by COSME in a search for solar
axions via their photon Primakoff conversion and Bragg scattering in the Ge
crystal yields a 95% C.L. limit for the axion-photon coupling g < 2.8 10^-9
GeV^-1. These data, analyzed for WIMP searches provide an exclusion plot for
WIMP-nucleon spin-independent interaction which improves previous plots in the
low mass region. On the other hand, the exclusion plot derived from the 60
kg-days of data from the RG-2 IGEX detector improves the exclusion limits
derived from other ionization (non thermal) germanium detector experiments in
the region of WIMP masses from 30 to 100 GeV recently singled out by the
reported DAMA annual modulation effect.

</DOC>
<DOC>
<DOCNO> 10936 </DOCNO>
Thermal conductivity and specific heat of the linear chain cuprate


  We report measurements of the specific heat and the thermal conductivity of
the model Heisenberg spin-1/2 chain cuprate Sr$_{2}$CuO$_{3}$ at low
temperatures. In addition to a nearly isotropic phonon heat transport, we find
a quasi one-dimensional excess thermal conductivity along the chain direction,
most likely associated with spin excitations (spinons). The spinon energy
current is limited mainly by scattering on defects and phonons. Analyzing the
specific heat data, the intrachain magnetic exchange $J/k_{B}$ is estimated to
be 2650 K.

</DOC>
<DOC>
<DOCNO> 101745 </DOCNO>
Gap probabilities in the finite and scaled Cauchy random matrix


  The probabilities for gaps in the eigenvalue spectrum of finite $ N\times N $
random unitary ensembles on the unit circle with a singular weight, and the
related hermitian ensembles on the line with Cauchy weight, are found exactly.
The finite cases for exclusion from single and double intervals are given in
terms of second order second degree ODEs which are related to certain
\mbox{Painlev\'e-VI} transcendents. The scaled cases in the thermodynamic limit
are again second degree and second order, this time related to
\mbox{Painlev\'e-V} transcendents. Using transformations relating the second
degree ODE and transcendent we prove an identity for the scaled bulk limit
which leads to a simple expression for the spacing p.d.f. We also relate all
the variables appearing in the Fredholm determinant formalism to particular
\mbox{Painlev\'e} transcendents, in a simple and transparent way, and exhibit
their scaling behaviour.

</DOC>
<DOC>
<DOCNO> 123264 </DOCNO>
The Stellar Content and Distance of UGC 4483


  We present HST/WFPC2 observations of UGC 4483, an irregular galaxy in the
M81/NGC 2403 complex. Stellar photometry was carried out with HSTphot, and is
complete to V ~ 26.0 and I ~ 24.7. We measure the red giant branch tip at I =
23.56 +/- 0.10 and calculated a distance modulus of (m-M)o = 27.53 +/- 0.12
(corresponding to a distance of 3.2 +/- 0.2 Mpc), placing UGC 4483 within the
NGC 2403 subgroup. We were able to measure properties of a previously-known
young star cluster in UGC 4483, finding integrated magnitudes of V = 18.66 +/-
0.21 and I = 18.54 +/- 0.10 for the stellar contribution (integrated light
minus Halpha and [OIII] contribution), corresponding to an age of ~10-15 Myr
and initial mass of ~10^4 Msun. This is consistent with the properties of the
cluster's brightest stars, which were resolved in the data for the first time.
Finally, a numerical analysis of the galaxy's stellar content yields a roughly
constant star formation rate of 1.3x10^-3 Msun/yr and mean metallicity of
[Fe/H] = -1.3 dex from 15 Gyr ago to the present.

</DOC>
<DOC>
<DOCNO> 39951 </DOCNO>
On the e/h Ratio of the Electromagnetic Calorimeter


  The method of extraction of the e/h ratio for an electromagnetic compartment
of a combined calorimeter is suggested and the non-compensation was determined.
The results agree with the Monte Carlo prediction and results of the weighting
method for electromagnetic compartment of combined calorimeter. The new easy
method of a hadronic energy reconstruction for a combined calorimeter is also
suggested. The proposed methods can be used for a combined calorimeter, which
is being designed to perform energy measurement in a next-generation high
energy collider experiment like ATLAS at LHC.

</DOC>
<DOC>
<DOCNO> 151038 </DOCNO>
Dilaton-driven brane inflation in type IIB string theory


  We consider the cosmological evolution of the three-brane in the background
of type IIB string theory. For two different backgrounds which give nontrivial
dilaton profile we have derived the Friedman-like equations. These give the
cosmological evolution which is similar to the one by matter density on the
universe brane. The effective density blows up as we move towards the
singularity showing the initial singularity problem. The analysis shows that
when there is axion field in the ambient space the recollapsing of the universe
occurs faster compared with the case without axion field.

</DOC>
<DOC>
<DOCNO> 117288 </DOCNO>
The two-time Green's Function and screened Self-Energy for two-electron


  Precise predictions of atomic energy levels require the use of QED,
especially in highly-charged ions, where the inner electrons have relativistic
velocities. We present an overview of the two-time Green's function method;
this method allows one to calculate level shifts in two-electron highly-charged
ions by including in principle all QED effects, for any set of states
(degenerate, quasi-degenerate or isolated).

</DOC>
<DOC>
<DOCNO> 72060 </DOCNO>
Gauge bosons in an SU(2)right x SU(2)left x G(leptonique) electroweak


  By considering its generalization to composite J=0 mesons proposed in a
previous work [1], I show how and why a chiral extension of the
Glashow-Salam-Weinberg standard model of electroweak interactions calls, there,
for right-handed charged W_R's coupled with g_R = e/cos(theta_W), and the
masses of which are related to the ones of the left-handed W_L's through the
relation M_L^2 + M_R^2 = M_Z^2. The mesonic sector, having vanishing baryonic
and leptonic number, is neutral with respect to the corresponding U(1)
symmetries, making the natural chiral gauge group to be [SU(2)left x
SU(2)right], blind to the presence of extra Z's. The W_R gauge bosons cannot
have been detected in hadronic colliders and can be very elusive in electroweak
processes involving, in particular, pseudoscalar mesons. Present data select
one among two possible extensions for which, in the right sector: - a specific
breaking of universality occurs between families of quarks, which belong to
inequivalent representations of SU(2)right; - the mixing angle is a free
parameter, constrained to be smaller than the Cabibbo angle by the box diagrams
controlling the K_L-K_S mass difference; this also minimizes contributions to
muon -> electron + photon. The relation g_L^2/M_L^2 = g_R^2/M_R^2 implements
left-right symmetry for low energy charged effective weak interactions. For the
sake of simplicity, this study is performed for two generations only.

</DOC>
<DOC>
<DOCNO> 100216 </DOCNO>
Resultats sur la dualite etrange sur le plan projectif


  We compute the dimensions of spaces of sections of all powers of the
Donaldson determinant bundle on the moduli space of rank 2 semi-stable sheaves
on the projective plane, with zero first Chern class, and second Chern class
equal to 3 or 4. We prove Le Potier's strange duality conjecture in some cases.

</DOC>
<DOC>
<DOCNO> 151074 </DOCNO>
Lectures on Non-BPS Dirichlet branes


  A comprehensive introduction to the boundary state approach to Dirichlet
branes is given. Various examples of BPS and non-BPS Dirichlet branes are
discussed. In particular, the non-BPS states in the duality of Type IIA on K3
and the heterotic string on T4 are analysed in detail.

</DOC>
<DOC>
<DOCNO> 152402 </DOCNO>
A groupoid approach to spaces of generalized connections


  The quantum completion of the space of connections in a manifold can be seen
as the set of all morphisms from the groupoid of the edges of the manifold to
the (compact) gauge group. This algebraic construction generalizes an analogous
description of the gauge-invariant quantum configuration space of Ashtekar and
Isham, clarifying the relation between the two spaces. We present a description
of the groupoid approach which brings the gauge-invariant degrees of freedom to
the foreground, thus making the action of the gauge group more transparent.

</DOC>
<DOC>
<DOCNO> 10268 </DOCNO>
Experimental Evidence for Electron Channelling in Fe/Au (100)


  We present transport and structural data from epitaxial (100) and (111) Au/Fe
multilayers grown by molecular beam epitaxy. From their analysis, we conclude
that an electron channelling mechanism, due to strong specular reflection of
the minority spin carrier at the Au/Fe interfaces, is responsible for the high
conductivity in the (100) multilayers.

</DOC>
<DOC>
<DOCNO> 121502 </DOCNO>
Dwarf Galaxies in Clusters: the Effects of a Violent Environment


  Recent observations suggest that dwarf galaxies pervade the universe, for
they have been encountered in large numbers in all the environments. However,
we present evidence that suggests dwarf galaxies may be subject to strong
dynamical processes in high density environments, the combined effects of
multiple encounters and the tidal effects due to the potential well of rich
clusters could result in the effective disruption of dwarf galaxies in the
clusters' central regions. Alternatively, the lack of dwarf galaxies in rich
environments has been interpreted in terms of a "density-morphology relation":
dwarf galaxies prefer low density environments (Phillipps et al. 1998). We
argue that such an explanation cannot account for the relationship between the
cD halo luminosity and the gas mass in the ICM, whereas the dwarf disruption
scenario proposed by Lopez-Cruz et al. (1997) addresses this naturally.

</DOC>
<DOC>
<DOCNO> 11377 </DOCNO>
Band gaps of primary metallic carbon nanotubes


  Primary metallic, or small gap semiconducting nanotubes, are tubes with band
gaps that arise solely from breaking the bond symmetry due to the curvature. We
derive an analytic expression for these gaps by considering how a general
symmetry breaking opens a gap in nanotubes with a well defined chiral wrapping
vector. This approach provides a straightforward way to include all types of
symmetry breaking effects, resulting in a simple unified gap equation as a
function of chirality and deformations.

</DOC>
<DOC>
<DOCNO> 83402 </DOCNO>
Noise Effects in Fuzzy Modelling Systems


  Noise is source of ambiguity for fuzzy systems. Although being an important
aspect, the effects of noise in fuzzy modeling have been little investigated.
This paper presents a set of tests using three well-known fuzzy modeling
algorithms. These evaluate perturbations in the extracted rule-bases caused by
noise polluting the learning data, and the corresponding deformations in each
learned functional relation. We present results to show: 1) how these fuzzy
modeling systems deal with noise; 2) how the established fuzzy model structure
influences noise sensitivity of each algorithm; and 3) whose characteristics of
the learning algorithms are relevant to noise attenuation.

</DOC>
<DOC>
<DOCNO> 12401 </DOCNO>
Accurate effective pair potentials for polymer solutions


  Dilute or semi-dilute solutions of non-intersecting self-avoiding walk (SAW)
polymer chains are mapped onto a fluid of ``soft'' particles interacting via an
effective pair potential between their centers of mass. This mapping is
achieved by inverting the pair distribution function of the centers of mass of
the original polymer chains, using integral equation techniques from the theory
of simple fluids. The resulting effective pair potential is finite at all
distances, has a range of the order of the radius of gyration, and turns out to
be only moderately concentration-dependent. The dependence of the effective
potential on polymer length is analyzed in an effort to extract the scaling
limit. The effective potential is used to derive the osmotic equation of state,
which is compared to simulation data for the full SAW segment model, and to the
predictions of renormalization group calculations. A similar inversion
procedure is used to derive an effective wall-polymer potential from the center
of mass density profiles near the wall, obtained from simulations of the full
polymer segment model. The resulting wall-polymer potential turns out to depend
strongly on bulk polymer concentration when polymer-polymer correlations are
taken into account, leading to a considerable enhancement of the effective
repulsion with increasing concentration. The effective polymer-polymer and
wall-polymer potentials are combined to calculate the depletion interaction
induced by SAW polymers between two walls. The calculated depletion interaction
agrees well with the ``exact'' results from much more computer-intensive direct
simulation of the full polymer-segment model, and clearly illustrates the
inadequacy -- in the semi-dilute regime -- of the standard Asakura-Oosawa
approximation based on the assumption of non-interacting polymer coils.

</DOC>
<DOC>
<DOCNO> 9535 </DOCNO>
The XX-model with boundaries. Part III:Magnetization profiles and


  We calculate the magnetization profiles of the $\sigma_j^x$ and $\sigma_j^z$
operators for the XX-model with hermitian boundary terms. We study the profiles
on the finite chain and in the continuum limit. The results are discussed in
the context of conformal invariance. We also discuss boundary excitations and
their effect on the magnetization profiles.

</DOC>
<DOC>
<DOCNO> 100262 </DOCNO>
A Frobenius-Schur theorem for Hopf algebras


  In this note we prove a generalization of the Frobenius-Schur theorem for
finite groups for the case of semisimple Hopf algebra over an algebraically
closed field of characteristic 0. A similar result holds in characteristic $p >
2$ if the Hopf algebra is also cosemisimple. In fact we show a more general
version for any finite-dimensional semisimple algebra with an involution.

</DOC>
<DOC>
<DOCNO> 80709 </DOCNO>
Matrix Models: Fermion Doubling vs. Anomaly


  We present some arguments showing spectrum doubling of matrix models in the
limit $N\to\infty$ which is connected with fermionic determinant behaviour. The
problems are similar to ones encountered in the lattice gauge theories with
chiral fermions. One may discuss the ``physical meaning'' of the doubling
states or ways to eliminate them. We briefly consider both situations.

</DOC>
<DOC>
<DOCNO> 68895 </DOCNO>
Is Cabibbo-Kobayasi-Maskawa Matrix Unitary?


  First, we give summary of the present values of CKM matrix elements. Then, we
discuss whether CKM matrix is unitary or not, and how we can find out if it is
not unitary.

</DOC>
<DOC>
<DOCNO> 152499 </DOCNO>
D-branes on Singularities: New Quivers from Old


  In this paper we present simplifying techniques which allow one to compute
the quiver diagrams for various D-branes at (non-Abelian) orbifold
singularities with and without discrete torsion. The main idea behind the
construction is to take the orbifold of an orbifold. Many interesting discrete
groups fit into an exact sequence $N\to G\to G/N$. As such, the orbifold $M/G$
is easier to compute as $(M/N)/(G/N)$ and we present graphical rules which
allow fast computation given the $M/N$ quiver.

</DOC>
<DOC>
<DOCNO> 13779 </DOCNO>
Suppression of Superconductivity in Mesoscopic Superconductors


  We propose a new boundary-driven phase transition associated with vortex
nucleation in mesoscopic superconductors (of size of the order of, or larger
than, the penetration depth). We derive the rescaling equations and we show
that boundary effects associated with vortex nucleation lowers the conventional
transition temperature in mesoscopic superconductors by an amount which is a
function of the size of the superconductor. This result explains recent
experiments in small superconductors where it was found that the transition
temperature depends on the size of the system and is lower than the critical
Berezinsk\u{i}-Kosterlitz-Thouless temperature.

</DOC>
<DOC>
<DOCNO> 152352 </DOCNO>
$Q{\bar Q}$ potential in the Schwinger model on curved space - time


  We study the confining and screening aspects of the Schwinger model on curved
static backgrounds.

</DOC>
<DOC>
<DOCNO> 83209 </DOCNO>
Extending and Implementing the Stable Model Semantics


  An algorithm for computing the stable model semantics of logic programs is
developed. It is shown that one can extend the semantics and the algorithm to
handle new and more expressive types of rules. Emphasis is placed on the use of
efficient implementation techniques. In particular, an implementation of
lookahead that safely avoids testing every literal for failure and that makes
the use of lookahead feasible is presented. In addition, a good heuristic is
derived from the principle that the search space should be minimized.
  Due to the lack of competitive algorithms and implementations for the
computation of stable models, the system is compared with three satisfiability
solvers. This shows that the heuristic can be improved by breaking ties, but
leaves open the question of how to break them. It also demonstrates that the
more expressive rules of the stable model semantics make the semantics clearly
preferable over propositional logic when a problem has a more compact logic
program representation. Conjunctive normal form representations are never more
compact than logic program ones.

</DOC>
<DOC>
<DOCNO> 178840 </DOCNO>
Effect of in-medium properties on heavy-ion collisions


  The properties of strange hadrons, i.e. of kaons and hyperons, in the nuclear
medium are discussed in connection with neutron star properties and
relativistic heavy-ion collisions. Firstly, the relevant medium modifications
of a kaon in a medium as provided by heavy-ion collisions is critically
examined within a coupled channel calculation. We demonstrate, that particle
ratios for kaons are not a sensitive probe of in-medium effects while the K-
flow is more suited to pin down the K- optical potential in dense matter.
Secondly, the interaction between hyperons is studied and may form bound states
which can be produced in relativistic heavy-ion collisions. Signals for the
detection of strange dibaryons by their decay topology and/or in the invariant
mass spectra are outlined.

</DOC>
<DOC>
<DOCNO> 101718 </DOCNO>
Mirror symmetry, Langlands duality, and commuting elements of Lie groups


  By normalizing the space of commuting pairs of elements in a reductive Lie
group G, and the corresponding space for the Langlands dual group, we construct
pairs of hyperkahler orbifolds which satisfy the conditions to be mirror
partners in the sense of Strominger-Yau-Zaslow. The same holds true for
commuting quadruples in a compact Lie group. The Hodge numbers of the mirror
partners, or more precisely their orbifold E-polynomials, are shown to agree,
as predicted by mirror symmetry. These polynomials are explicitly calculated
when G is a quotient of SL(n).

</DOC>
<DOC>
<DOCNO> 101401 </DOCNO>
Commutative complex numbers in four dimensions


  Commutative complex numbers of the form u=x+\alpha y+\beta z+\gamma t in 4
dimensions are studied, the variables x, y, z and t being real numbers. Four
distinct types of multiplication rules for the complex bases \alpha, \beta and
\gamma are investigated, which correspond to hypercomplex entities called in
this paper circular fourcomplex numbers, hyperbolic fourcomplex numbers, planar
fourcomplex numbers, and polar fourcompex numbers. Exponential and
trigonometric forms for the fourcomplex numbers are given in all these cases.
Expressions are given for the elementary functions of the fourcomplex variables
mentioned above. Relations of equality exist between the partial derivatives of
the real components of the functions of fourcomplex variables. The integral of
a fourcomplex function between two points is independent of the path connecting
the points. The concepts of poles and residues can be introduced for the
circular, planar, and polar fourcomplex numbers, for which the exponential
forms depend on cyclic variables. A hypercomplex polynomial can be written as a
product of linear factors for circular and planar fourcomplex numbers, and as a
product of linear or quadratic factors for the hyperbolic and polar fourcomplex
numbers.

</DOC>
<DOC>
<DOCNO> 68558 </DOCNO>
Quantum fluctuations of the quark condensate


  The quantum fluctuations of the quark condensate are studied in a Nambu
Jona-Lasinio model. Two Lorenz invariant regularizations are considered: a
sharp 4-momentum cut-off and a soft gaussian regulator. The quantum
fluctuations of the quark condensate are found to be large although chiral
symmetry is not restored. Instabilities of the ground state appear when the
system is probed by a source term proportional to the squared quark condensate.
The instabilities are traced to unphysical poles introduced by the regulator
and their effect is greatly enhanced when a sharp cut-off is used.

</DOC>
<DOC>
<DOCNO> 119834 </DOCNO>
Optical and Infrared photometry of the type IIn SN 1998S:Days 11-146


  We present contemporaneous optical and infrared photometric observations of
the type IIn SN 1998S covering the period between 11 and 146 days after
discovery. The infrared data constitute the first ever infrared light curves of
a type IIn supernova. We use blackbody and spline fits to the photometry to
examine the luminosity evolution. During the first 2--3 months, the luminosity
is dominated by the release of shock-deposited energy in the ejecta. After
$\sim$100 days the luminosity is powered mostly by the deposition of
radioactive decay energy from 0.15$\pm$0.05 M$_{\odot}$ of $^{56}$Ni which was
produced in the explosion. We also report the discovery of an astonishingly
high infrared (IR) excess, $K-L'=2.5$, that was present at day 130. We
interpret this as being due to thermal emission from dust grains in the
vicinity of the supernova. We argue that to produce such a high IR luminosity
so soon after the explosion, the dust must be {\it pre-existing} and so is
located in the circumstellar medium of the progenitor. The dust could be heated
either by the UV/optical flash (IR echo) or by the X-rays from the interaction
of the ejecta with the circumstellar material

</DOC>
<DOC>
<DOCNO> 152092 </DOCNO>
On the Classification of N-extended Supersymmetric Quantum Mechanical


  In this paper some properties of the irreducible multiplets of representation
for the N = (p, q) - extended supersymmetry in one dimension are discussed.
Essentially two results are here presented. At first a peculiar property of the
one dimension is exhibited, namely that any multiplet containing 2d (d bosonic
and d fermionic) particles in M different spin states, is equivalent to a (d,d)
multiplet of just 2 spin states (all bosons and all fermions being grouped in
the same spin). Later, it is shown that the classification of all multiplets of
this kind carrying an irreducible representation of the N - extended
supersymmetry is in one-to-one correspondence with the classification of
real-valued Clifford Gamma-matrices of Weyl type. In particular, p+q is mapped
into D, the space-time dimensionality, while 2d is determined to be the
dimensionality of the corresponding Gamma-matrices. The implications of these
results to the theory of spinning particles are analyzed.

</DOC>
<DOC>
<DOCNO> 101136 </DOCNO>
Discreteness of spectrum for the magnetic Schr\"odinger operators. I


  We provide sufficient conditions for the discreteness of spectrum for
magnetic Schr\"odinger operators. They generalize the classical result by
K.Friedrichs (1934) and earlier results by J.Avron, I.Herbst and B.Simon
(1978), A.Dufresnoy (1983) and A.Iwatsuka (1990) which were obtained in the
absence of electric field. Our conditions are formulated as conditions of
growth at infinity for some effective potentials. More precise sufficient
conditions are formulated by use of the Wiener capacity and extend earlier work
by A.M.Molchanov (1953) and V.Kondratiev and M.Shubin (1999) who considered the
case of the operator without magnetic field. These conditions become necessary
and sufficient in case when there is no magnetic field and the electric
potential is semi-bounded below.

</DOC>
<DOC>
<DOCNO> 9835 </DOCNO>
State, rate and temperature-dependent sliding friction of elastomers


  We present an experimental investigation of the non stationary frictional
properties of multicontact interfaces between rough elastomers and rough hard
glass at low velocities (<= 200 mu m s^{-1}). These systems, for which the
deformation contribution to friction is negligible, are shown to exhibit a
phenomenology which is similar to what is observed for non elastomeric
materials in the same multi-contact configuration, and which are quantitatively
described by the state- and rate-dependent friction laws. This permits to
identify clearly the two contributions to adhesive friction which are mixed in
steady sliding: the interfacial shear stress which appears as thermally
activated formation and breaking of molecular bonds, and the real area of
contact which evolves through viscoelastic creep of the load bearing
asperities.

</DOC>
<DOC>
<DOCNO> 100917 </DOCNO>
Nonabelian mixed Hodge structures


  We propose a definition of ``nonabelian mixed Hodge structure'' together with
a construction associating to a smooth projective variety $X$ and to a
nonabelian mixed Hodge structure $V$, the ``nonabelian cohomology of $X$ with
coefficients in $V$'' which is a (pre-)nonabelian mixed Hodge structure denoted
$H=Hom(X_M, V)$. We describe the basic definitions and then give some
conjectures saying what is supposed to happen. At the end we compute an
example: the case where $V$ has underlying homotopy type the complexified
2-sphere, and mixed Hodge structure coming from its identification with $\pp
^1$. For this example we show that $Hom (X_M,V)$ is a namhs for any smooth
projective variety $X$.

</DOC>
<DOC>
<DOCNO> 69351 </DOCNO>
Grand Unified Theories without the Desert


  We present a Grand Unified Theory (GUT) that has GUT fields with masses of
the order of a TeV, but at the same time preserves (at the one-loop level) the
success of gauge-coupling unification of the MSSM and the smallness of proton
decay operators. This scenario is based on a five-dimensional theory with the
extra dimension compactified as in the Randall-Sundrum model. The MSSM gauge
sector and its GUT extension live in the 5D bulk, while the matter sector is
localized on a 4D boundary.

</DOC>
<DOC>
<DOCNO> 151214 </DOCNO>
A New Current Regularization of Thirring Model


  We study an ambiguity of the current regularization in the Thirring model. We
find a new current definition which enables to make a comprehensive treatment
of the current. Our formulation is simpler than Klaiber's formulation. We
compare our result with other formulations and find a very good agreement with
their result. We also obtain the Schwinger term and the general formula for any
current regularization.

</DOC>
<DOC>
<DOCNO> 7746 </DOCNO>
Probing quantum statistical mechanics with Bose gases: Non-trivial order


  This is a less technical presentation of the ideas in quant-ph/9804035 [Phys
Rev Lett 83 (1999), 1707-1710]. A second order phase transition induced by a
rapid quench can lock out topological defects with densities far exceeding
their equilibrium expectation values. This phenomenon is a generic prediction
of nonequilibrium statistical mechanics, and can appear in a wide range of
physical systems. We discuss it qualitatively in the context of trapped dilute
Bose-Einstein condensates, outline a simple quantitative theory based on the
time-dependent Ginzburg-Landau equation, and briefly compare the results of
quantum kinetic theory.

</DOC>
<DOC>
<DOCNO> 9770 </DOCNO>
Stripes in Doped Antiferromagnets: Single-Particle Spectral Weight


  Recent photoemission (ARPES) experiments on cuprate superconductors provide
important guidelines for a theory of electronic excitations in the stripe
phase. Using a cluster perturbation theory, where short-distance effects are
accounted for by exact cluster diagonalization and long-distance effects by
perturbation (in the hopping), we calculate the single-particle Green's
function for a striped t-J model. The data obtained quantitatively reproduce
salient (ARPES-) features and may serve to rule out "bond-centered" in favor of
"site-centered" stripes.

</DOC>
<DOC>
<DOCNO> 178702 </DOCNO>
Lepton U_l(1) symmetry and interaction of neutrinos with deuterons at


  The following items are discussed: 1. The lepton U_l(1) symmetry and its
relation to the presence of the neutrino mass term in the Hamiltonian. 2. The
possibility of the measurement of the neutrino-deuteron reactions with high
energy neutrinos at SNO by using neutrinos from a neutrino factory. 3. The weak
axial one-boson exchange currents for the Bethe-Salpeter equation.

</DOC>
<DOC>
<DOCNO> 83413 </DOCNO>
A Public-key based Information Management Model for Mobile Agents


  Mobile code based computing requires development of protection schemes that
allow digital signature and encryption of data collected by the agents in
untrusted hosts. These algorithms could not rely on carrying encryption keys if
these keys could be stolen or used to counterfeit data by hostile hosts and
agents. As a consequence, both information and keys must be protected in a way
that only authorized hosts, that is the host that provides information and the
server that has sent the mobile agent, could modify (by changing or removing)
retrieved data. The data management model proposed in this work allows the
information collected by the agents to be protected against handling by other
hosts in the information network. It has been done by using standard public-key
cryptography modified to support protection of data in distributed environments
without requiring an interactive protocol with the host that has dropped the
agent. Their significance stands on the fact that it is the first model that
supports a full-featured protection of mobile agents allowing remote hosts to
change its own information if required before agent returns to its originating
server.

</DOC>
<DOC>
<DOCNO> 119981 </DOCNO>
USA and RXTE Observations of a Variable Low-Frequency QPO in XTE


  The USA experiment on ARGOS and RXTE have exensively observed the X-ray
transient XTE J1118+480 during its recent outburst in 2000 April--June. We
present detailed monitoring of the evolution of a low frequency QPO which
drifts from 0.07 Hz to 0.15 Hz during the outburst. We examine possible
correlations of the QPO frequency with the flux and spectral characteristics of
the source, and compare this QPO to low frequency QPOs observed in other black
hole candidates.

</DOC>
<DOC>
<DOCNO> 68796 </DOCNO>
Vacuum selection by recollapsing


  We discuss the possibility that the vacuum is dynamically determined in the
history of the universe. The point is that some of the bubbles with a certain
vacuum shrink by the evolution of the universe via gravity and may become black
holes. When the temperature of the phase transition T_{PT} is higher than 10^9
GeV, these black holes evaporate until now. If T_{PT}<10^9 GeV, we may see
these black holes in our universe. It is interesting that in many cases false
vacua are favored in the context of cosmology. By using this argument,
supersymmetry(SUSY), if it exists, can be broken cosmologically. We can guess
the SUSY breaking scale from the mass of the black holes.

</DOC>
<DOC>
<DOCNO> 11806 </DOCNO>
Modelling of dislocation generation and interaction during high-speed


  Recent experiments by Kiritani et al. have revealed a surprisingly high rate
of vacancy production during high-speed deformation of thin foils of fcc
metals. Virtually no dislocations are seen after the deformation. This is
interpreted as evidence for a dislocation-free deformation mechanism at very
high strain rates.
  We have used molecular-dynamics simulations to investigate high-speed
deformation of copper crystals. Even though no pre-existing dislocation sources
are present in the initial system, dislocations are quickly nucleated and a
very high dislocation density is reached during the deformation.
  Due to the high density of dislocations, many inelastic interactions occur
between dislocations, resulting in the generation of vacancies. After the
deformation, a very high density of vacancies is observed, in agreement with
the experimental observations. The processes responsible for the generation of
vacancies are investigated. The main process is found to be incomplete
annihilation of segments of edge dislocations on adjacent slip planes. The
dislocations are also seen to be participating in complicated dislocation
reactions, where sessile dislocation segments are constantly formed and
destroyed.

</DOC>
<DOC>
<DOCNO> 13975 </DOCNO>
Neighborhood preferences in random matching problems


  We consider a class of random matching problems where the distance between
two points has a probability law which, for a small distance l, goes like l^r.
In the framework of the cavity method, in the limit of an infinite number of
points, we derive equations for p_k, the probability for some given point to be
matched to its k-th nearest neighbor in the optimal configuration. These
equations are solved in two limiting cases : r=0 - where we recover p_k=1/2^k,
as numerically conjectured by Houdayer et al. and recently rigorously proved by
Aldous - and r -> +infty. For 0<r<+infty, we are not able to solve the
equations analytically, but we compute the leading behavior of p_k for large k.

</DOC>
<DOC>
<DOCNO> 101512 </DOCNO>
Triangular Hopf algebras with the Chevalley property


  We say that a Hopf algebra has the Chevalley property if the tensor product
of any two simple modules over this Hopf algebra is semisimple. In this paper
we classify finite dimensional triangular Hopf algebras with the Chevalley
property, over the field of complex numbers. Namely, we show that all of them
are twists of triangular Hopf algebras with R-matrix having rank <=2, and
explain that the latter ones are obtained from group algebras of finite
supergroups by a simple modification procedure. We note that all examples of
finite dimensional triangular Hopf algebras which are known to the authors, do
have Chevalley property, so one might expect that our classification
potentially covers all finite dimensional triangular Hopf algebras.

</DOC>
<DOC>
<DOCNO> 13569 </DOCNO>
Metastable states of a ferromagnet on random thin graphs


  We calculate the mean number of metastable states of an Ising ferromagnet on
random thin graphs of fixed connectivity c. We find, as for mean field spin
glasses that this mean increases exponentially with the number of sites, and is
the same as that calculated for the +/- J spin glass on the same graphs. An
annealed calculation of the number <N_{MS}(E)> of metastable states of energy E
is carried out. For small c, an analytic result is obtained. The result is
compared with the one obtained for spin glasses in order to discuss the role
played by loops on thin graphs and hence the effect of real frustration on the
distribution of metastable states.

</DOC>
<DOC>
<DOCNO> 40340 </DOCNO>
$t\bar t$ cross section near the production threshold in NNLO of NRQCD


  The cross section near the $t\bar t$ production threshold in $e^+e^-$
annihilation and $\gamma\gamma$ collisions is discussed. The NNLO results
within NRQCD are briefly overviewed.

</DOC>
<DOC>
<DOCNO> 84722 </DOCNO>
Quasi-normal modes of charged, dilaton black holes


  In this paper we study the perturbations of the charged, dilaton black hole,
described by the solution of the low energy limit of the superstring action
found by Garfinkle, Horowitz and Strominger. We compute the complex frequencies
of the quasi-normal modes of this black hole, and compare the results with
those obtained for a Reissner-Nordstr\"{o}m and a Schwarzschild black hole. The
most remarkable feature which emerges from this study is that the presence of
the dilaton breaks the \emph{isospectrality} of axial and polar perturbations,
which characterizes both Schwarzschild and Reissner-Nordstr\"{o}m black holes.

</DOC>
<DOC>
<DOCNO> 69710 </DOCNO>
Parton Distributions Working Group


  The main focus of this working group was to investigate the different issues
associated with the development of quantitative tools to estimate parton
distribution functions uncertainties. In the conclusion, we introduce a
"Manifesto" that describes an optimal method for reporting data.

</DOC>
<DOC>
<DOCNO> 10530 </DOCNO>
Heuristic derivation of continuum kinetic equations from microscopic


  We present an approximate and heuristic scheme for the derivation of
continuum kinetic equations from microscopic dynamics for stochastic,
interacting systems. The method consists of a mean-field type, decoupled
approximation of the master equation followed by the `naive' continuum limit.
The Ising model and driven diffusive systems are used as illustrations. The
equations derived are in agreement with other approaches, and consequences of
the microscopic dependences of coarse-grained parameters compare favorably with
exact or high-temperature expansions. The method is valuable when more
systematic and rigorous approaches fail, and when microscopic inputs in the
continuum theory are desirable.

</DOC>
<DOC>
<DOCNO> 71606 </DOCNO>
CP Violation and Family Mixing in the Effective Electroweak Lagrangian


  We construct the most general effective Lagrangian of the matter sector of
the Standard Model, including mixing and CP violating terms. The Lagrangian
contains the effective operators that give the leading contribution in theories
where the physics beyond the Standard Model shows at a scale $\Lambda >>M_{W}$.
We perform the diagonalization and passage to the physical basis in full
generality. We determine the contribution to the different observables and
discuss the possible new sources of CP violation, the idea being to be able to
gain some knowledge about new physics beyond the Standard Model from general
considerations, without having to compute model by model. The values of the
coefficients of the effective Lagrangian in some theories, including the
Standard Model, are presented and we try to draw some general conclusions about
the general pattern exhibited by physics beyond the Standard Model in what
concerns CP violation. In the process we have had to deal with two theoretical
problems which are very interesting in their own: the renormalization of the
CKM matrix elements and the wave function renormalization in the on-shell
scheme when mixing is present.

</DOC>
<DOC>
<DOCNO> 11616 </DOCNO>
Dynamic Phase Transition, Universality, and Finite-size Scaling in the


  We study the two-dimensional kinetic Ising model below its equilibrium
critical temperature, subject to a square-wave oscillating external field. We
focus on the multi-droplet regime where the metastable phase decays through
nucleation and growth of many droplets of the stable phase. At a critical
frequency, the system undergoes a genuine non-equilibrium phase transition, in
which the symmetry-broken phase corresponds to an asymmetric stationary limit
cycle for the time-dependent magnetization. We investigate the universal
aspects of this dynamic phase transition at various temperatures and field
amplitudes via large-scale Monte Carlo simulations, employing finite-size
scaling techniques adopted from equilibrium critical phenomena. The critical
exponents, the fixed-point value of the fourth-order cumulant, and the critical
order-parameter distribution all are consistent with the universality class of
the two-dimensional equilibrium Ising model. We also study the cross-over from
the multi-droplet to the strong-field regime, where the transition disappears.

</DOC>
<DOC>
<DOCNO> 178768 </DOCNO>
The Effect of Deformation on the Twist Mode


  Using $^{12}$C as an example of a strongly deformed nucleus we calculate the
strengths and energies in the asymptotic (oblate) deformed limit for the
isovector twist mode operator $[rY^{1}\vec{l}]^{\lambda=2}t_{+}$ where l is the
orbital angular momentum. We also consider the $\lambda =1$ case. For
$\lambda=0$, the operator vanishes. Whereas in a $\Delta N=0$ Nilsson model the
summed strength is independent of the relative P$_{3/2}$ and P$_{1/2}$
occupancy when we allow for different frequencies $\omega_{i}$ in the x, y, and
z directions there is a weak dependency on deformation.

</DOC>
<DOC>
<DOCNO> 72026 </DOCNO>
Supersymmetric penguin contributions to the decay b -> s gamma with


  We give explicit expressions for the amplitudes associated with the
supersymmetric contributions to the process: b -> s gamma in the context of
SUSY extensions of Standard Model with non-universal soft SUSY breaking terms.
  From experimental data, we deduce the limits on the squark mass insertions
obtained from different contributions (gluinos, neutralinos and charginos).

</DOC>
<DOC>
<DOCNO> 84330 </DOCNO>
Yang-Mills Instantons in the Gravitational Instanton Backgrounds


  The simplest and the most straightforward new algorithm for generating
solutions to (anti) self-dual Yang-Mills (YM) equation in the typical
gravitational instanton backgrounds is proposed. When applied to the Taub-NUT
and the Eguchi-Hanson metrics, the two best-known gravitational instantons, the
solutions turn out to be the rather exotic type of instanton configurations
carrying finite YM action but generally fractional topological charge values.

</DOC>
<DOC>
<DOCNO> 116303 </DOCNO>
Inverse Time-Dependent Quantum Mechanics


  Using a new Bayesian method for solving inverse quantum problems, potentials
of quantum systems are reconstructed from coordinate measurements in
non-stationary states. The approach is based on two basic inputs: 1. a
likelihood model, providing the probabilistic description of the measurement
process as given by the axioms of quantum mechanics, and 2. additional "a
priori" information implemented in form of stochastic processes over
potentials.

</DOC>
<DOC>
<DOCNO> 150868 </DOCNO>
Difference equations for correlation functions of Belavin's


  Belavin's $\mathbb{Z}_n$-symmetric elliptic model with boundary reflection is
considered on the basis of the boundary CTM bootstrap. We find non-diagonal
$K$-matrices for $n>2$ that satisfy the reflection equation (boundary
Yang--Baxter equation), and also find non-diagonal Boltzmann weights for the
$A^{(1)}_{n-1}$-face model even for $n\geqq 2$. We derive difference equations
of the quantum Knizhnik-Zamolodchikov type for correlation functions of the
boundary model. The boundary spontaneous polarization is obtained by solving
the simplest difference equations. The resulting quantity is the square of the
spontaneous polarization for the bulk $\mathbb{Z}_n$-symmetric model, up to a
phase factor.

</DOC>
<DOC>
<DOCNO> 8935 </DOCNO>
Impurity Scattering in Carbon Nanotubes with Superconducting Pair


  Effects of the superconducting pair potential on the impurity scattering
processes in metallic carbon nanotubes are studied theoretically. The backward
scattering of electrons vanishes in the normal state. In the presence of the
superconducting pair correlations, the backward scatterings of electron- and
hole-like quasiparticles vanish, too. The impurity gives rise to backward
scatterings of holes for incident electrons, and it also induces backward
scatterings of electrons for incident holes. Negative and positive currents
induced by such the scatterings between electrons and holes cancel each other.
Therefore, the nonmagnetic impurity does not hinder the supercurrent in the
regions where the superconducting proximity effects occur, and the carbon
nanotube is a good conductor for Cooper pairs. Relations with experiments are
discussed.

</DOC>
<DOC>
<DOCNO> 71986 </DOCNO>
Single chargino production via gluon-gluon fusion in a supersymmetric


  We studied the production of single chargino$\tilde{\chi}_1^{\pm}$
accompanied by $\mu^{\mp}$ lepton via gluon-gluon fusion at the LHC. The
numerical analysis of their production rates is carried out in the mSUGRA
scenario with some typical parameter sets. The results show that the cross
sections of the $\tilde{\chi}_1^{\pm}\mu^{\mp}$ productions via gluon-gluon
collision are in the order of $1 \sim 10^{2}$ femto barn quantitatively at the
CERN LHC, and can be competitive with production mechanism via quark-antiquark
annihilation process.

</DOC>
<DOC>
<DOCNO> 118337 </DOCNO>
Optical Observations of Type II Supernovae


  I present an overview of optical observations (mostly spectra) of Type II
supernovae. SNe II are defined by the presence of hydrogen, and exhibit a very
wide variety of properties. SNe II-L tend to show evidence of late-time
interaction with circumstellar material. SNe IIn are distinguished by
relatively narrow emission lines with little or no P-Cygni absorption component
and (quite often) slowly declining light curves; they probably have unusually
dense circumstellar gas with which the ejecta interact. Some SNe IIn, however,
might not be genuine SNe, but rather are super-outbursts of luminous blue
variables. The progenitors of SNe IIb contain only a low-mass skin of hydrogen;
their spectra gradually evolve to resemble those of SNe Ib. Limited
spectropolarimetry thus far indicates large asymmetries in the ejecta of SNe
IIn, but much smaller ones in SNe II-P. There is intriguing, but still
inconclusive, evidence that some peculiar SNe IIn might be associated with
gamma-ray bursts. SNe II-P are useful for cosmological distance determinations
with the Expanding Photosphere Method, which is independent of the Cepheid
distance scale.

</DOC>
<DOC>
<DOCNO> 9439 </DOCNO>
Effect of quantum interference in the nonlinear conductance of


  The influence of the interference of electron waves, which were scattered by
single impurities, on nonlinear quantum conductance of metallic
microconstrictions (as was recently investigated experimentally) is studied
theoretically. The dependence of the interference pattern in the conductance
$G(V)$ on the contact diameter and the spatial distribution of impurities is
analyzed. It is shown that the amplitude of conductance oscillation is strongly
depended on the position of impurities inside the constriction.

</DOC>
<DOC>
<DOCNO> 178974 </DOCNO>
Moments of Inertia of Nuclei in the Rare Earth Region: A Relativistic


  A parameter free investigation of the moments of inertia of ground state
rotational bands in well deformed rare-earth nuclei is carried out using
Cranked Relativistic Hartree-Bogoliubov (CRHB) and non-relativistic Cranked
Hartree-Fock-Bogoliubov (CHFB) theories. In CRHB theory, the relativistic
fields are determined by the non-linear Lagrangian with the NL1 force and the
pairing interaction by the central part of finite range Gogny D1S force. In
CHFB theory, the properties in particle-hole and particle-particle channels are
defined solely by Gogny D1S forces. Using an approximate particle number
projection before variation by means of the Lipkin Nogami method improves the
agreement with the experimental data, especially in CRHB theory. The effect of
the particle number projection on the moments of inertia and pairing energies
is larger in relativistic than in non-relativistic theory.

</DOC>
<DOC>
<DOCNO> 169630 </DOCNO>
Globally singularity-free semi-classical wave functions in closed form


  We use a factorization technique and representation of canonical
transformations to construct globally valid closed form expressions without
singularities of semi-classical wave functions for arbitrary smooth potentials
over a one-dimensional position space.

</DOC>
<DOC>
<DOCNO> 102373 </DOCNO>
Equisingular Deformations of Plane Curve and of Sandwiched Singularities


  Let $C$ be an isolated plane curve singularity, and $(C,l)$ be a decorated
curve. In this article we compare the equisingular deformations of $C$ and the
sandwiched singularity $X(C,l)$. We will prove that for $l \gg 0$ the functor
of equisingular deformations of $C$ and $(C,l)$ are equivalent. From this we
deduce a proof of a formula for the dimension of the equisingular stratum.
  Furthermore we will show how compute the equisingularity ideal of the curve
singularity $C$, given the minimal (good) resolution of $C$.

</DOC>
<DOC>
<DOCNO> 102811 </DOCNO>
The Complexity of Finding Small Triangulations of Convex 3-Polytopes


  The problem of finding a triangulation of a convex three-dimensional polytope
with few tetrahedra is proved to be NP-hard. We discuss other related
complexity results.

</DOC>
<DOC>
<DOCNO> 72199 </DOCNO>
A practical gauge invariant regularization of the SO(10) grand unified


  It is shown that a simple modification of the dimensional regularization
allows to compute in a consistent and gauge invariant way any diagram with less
than four loops in the SO(10) unified model. The method applies also to the
Standard Model generated by the symmetry breaking $SO(10) \to SU(3)\times
SU(2)\times U(1)$. A gauge invariant regularization for arbitrary diagram is
also described.

</DOC>
<DOC>
<DOCNO> 13091 </DOCNO>
Field-induced metal-insulator transition in a two-dimensional organic


  The quasi-two-dimensional organic superconductor
beta-(BEDT-TTF)_2SF_5CH_2CF_2SO_3 (T_c approx 4.4 K)shows very strong
Shubnikov-de Haas (SdH) oscillations which are superimposed on a highly
anomalous steady background magnetoresistance, R_b. Comparison with de Haas-
van Alphen oscillations allow a reliable estimate of R_b which is crucial for
the correct extraction of the SdH signal. At low temperatures and high magnetic
fields insulating behavior evolves. The magnetoresistance data violate Kohler's
rule, i.e., cannot be described within the framework of semiclassical transport
theory, but converge onto a universal curve appropriate for dynamical scaling
at a metal-insulator transition.

</DOC>
<DOC>
<DOCNO> 119357 </DOCNO>
Cosmological Evolution Models for QSO/AGN Luminosity Functions: Effects


  We investigate a large number of cosmological evolution models for QSOs and
Active Galactic Nuclei (AGN). We introduce a spectrum-luminosity correlation as
a new input parameter and adopt the estimated mass function (MF) of massive
black holes in centers of nearby galactic nuclei as a constraint to distinguish
among different QSO/AGN models. We explore three basic types of
phenomenological scenarios; (i) Models with multiple short-lived ($\sim$ a few
$10^{6-8}$ yrs) populations, (ii) Models with a single long-lived ($\sim 10^9$
yr) QSO population, and (iii) Models with recurrent QSO/AGN activities which
are driven by long-term variabilities of the disk instability type. In each
model, we derive the expected theoretical luminosity function (LF) and the MF
of black holes which grow through mass accretion. We assess the plausibility of
each model based on whether each model's LF and MF are compatible with the
observed data. We find that the best fits to the observed LFs are obtained in
the model with multiple short-lived populations and without any significant
spectral evolution. This finding suggests that the QSO populations may be
composed of many short-lived generations ($\sim$ a few 10$^8$ yrs) and that
there is no significant spectral evolution within each generation. On the other
hand, we also show that there is no satisfactory model which can simultaneously
account for the observed LF and the estimated MF. We speculate that some of the
present-day black holes (BHs) found in galactic nuclei may have formed without
undergoing the QSO/AGN phase.

</DOC>
<DOC>
<DOCNO> 12293 </DOCNO>
Testing Bell's Inequality with Ballistic Electrons in Semiconductors


  We propose an experiment to test Bell's inequality violation in
condensed-matter physics. We show how to generate, manipulate and detect
entangled states using ballistic electrons in Coulomb-coupled semiconductor
quantum wires. Due to its simplicity (only five gates are required to prepare
entangled states and to test Bell's inequality), the proposed
semiconductor-based scheme can be implemented with currently available
technology. Moreover, its basic ingredients may play a role towards large-scale
quantum-information processing in solid-state devices.

</DOC>
<DOC>
<DOCNO> 99961 </DOCNO>
Variations on deformation quantization


  I have chosen, in this presentation of Deformation Quantization, to focus on
3 points: the uniqueness --up to equivalence-- of a universal star product
(universal in the sense of Kontsevich) on the dual of a Lie algebra, the
cohomology classes introduced by Deligne for equivalence classes of
differential star products on a symplectic manifold and the construction of
some convergent star products on Hermitian symmetric spaces. Those subjects
will appear in a promenade through the history of existence and equivalence in
deformation quantization.

</DOC>
<DOC>
<DOCNO> 72180 </DOCNO>
A Pati-Salam model from branes


  We explore the possibility of embedding the Pati-Salam model in the context
of Type I brane models. We study a generic model with U(4)_C x U(2)_L x U(2)_R
gauge symmetry and matter fields compatible with a Type I brane configuration.
Examining the anomaly cancellation conditions of the surplus abelian symmetries
we find an alternative hypercharge embedding that is compatible with a low
string/brane scale of the order of 5-7 TeV, when the U(4)_C and U(2)_R brane
stack couplings are equal. Proton stability is assured as baryon number is
associated to a global symmetry remnant of the broken abelian factors. It is
also shown that this scenario can accommodate an extra low energy abelian
symmetry that can be associated to lepton number. The issue of fermion and
especially neutrino masses is also discussed.

</DOC>
<DOC>
<DOCNO> 9319 </DOCNO>
Continuous time dynamics of the Thermal Minority Game


  We study the continuous time dynamics of the Thermal Minority Game. We find
that the dynamical equations of the model reduce to a set of stochastic
differential equations for an interacting disordered system with non-trivial
random diffusion. This is the simplest microscopic description which accounts
for all the features of the system. Within this framework, we study the phase
structure of the model and find that its macroscopic properties strongly depend
on the initial conditions.

</DOC>
<DOC>
<DOCNO> 8449 </DOCNO>
Comment on: "Auger decay, Spin-exchange, and their connection to


  It is shown that the interconversion mechanism for the triplet excitons in
Cu_2O suggested recently by G.M. Kavoulakis and A. Mysyrowicz in
cond-mat/0001438 can be tested by the two-photon direct creation of the triplet
excitons.

</DOC>
<DOC>
<DOCNO> 83088 </DOCNO>
Computing and Comparing Semantics of Programs in Multi-valued Logics


  The different semantics that can be assigned to a logic program correspond to
different assumptions made concerning the atoms whose logical values cannot be
inferred from the rules. Thus, the well founded semantics corresponds to the
assumption that every such atom is false, while the Kripke-Kleene semantics
corresponds to the assumption that every such atom is unknown. In this paper,
we propose to unify and extend this assumption-based approach by introducing
parameterized semantics for logic programs. The parameter holds the value that
one assumes for all atoms whose logical values cannot be inferred from the
rules. We work within multi-valued logic with bilattice structure, and we
consider the class of logic programs defined by Fitting.
  Following Fitting's approach, we define a simple operator that allows us to
compute the parameterized semantics, and to compare and combine semantics
obtained for different values of the parameter. The semantics proposed by
Fitting corresponds to the value false. We also show that our approach captures
and extends the usual semantics of conventional logic programs thereby unifying
their computation.

</DOC>
<DOC>
<DOCNO> 100905 </DOCNO>
Superconformal vertex algebras in differential geometry. I


  We show how to construct an N=1 superconformal vertex algebra (SCVA) from any
Riemannian manifold. When the Riemannian manifold has special holonomy groups,
we discuss the extended supersymmetry. When the manifold is complex or
K\"{a}hler, we also generalize the construction to obtain N=2 SCVA's. We study
the BRST cohomology groups of the topological vertex algebras obtained by the
$A$ twist and the $B$ twist from these N=2 SCVA's. We show that for one of
them, the BRST cohomologies are isomorphic to $H^*(M, \Lambda^*(T^*M))$ and
$H^*(M, \Lambda^*(TM))$ respectively. This provides a mathematical formulation
of the $A$ theory and $B$ theory in physics literature. The connection with
elliptic genera is also discussed. Furthermore, when the manifold is
hyperk\"{a}hler, we generalize our constructions to obtain N=4 SCVA's. A
heuristic relationship with super loop space is also discussed.

</DOC>
<DOC>
<DOCNO> 116366 </DOCNO>
Electromagnetic interaction between two uniformly moving charged


  This paper presents an intuitive, geometrical derivation of the relativistic
addition of velocities, and of the electromagnetic interaction between two
uniformly moving charged particles, based on 2 spatial + 1 temporal dimensional
Minkowski diagrams. We calculate the relativistic addition of velocities by
projecting the world-line of the particle on the spatio-temporal planes of the
reference frames considered. We calculate the real component of the electro-
magnetic 4-force, in the proper reference frame of the source particle,
starting from the Coulomb force generated by a charged particle at rest. We
then obtain the imaginary component of the 4-force, in the same reference
frame, from the requirement that the 4-force be orthogonal to the 4-velocity.
The 4-force is then projected on a real 3 dimensional space to get the Lorentz
force.

</DOC>
<DOC>
<DOCNO> 151054 </DOCNO>
A Black Hole Farey Tail


  We derive an exact expression for the Fourier coefficients of elliptic genera
of Calabi-Yau manifolds. When applied to k-fold symmetric products of K3
surfaces the expression is well-suited to studying the AdS/CFT correspondence
on AdS3 x S3. The expression also elucidates an SL(2,Z) invariant phase diagram
for the D1/D5 system involving deconfining transitions in the limit as k goes
to infinity.

</DOC>
<DOC>
<DOCNO> 151782 </DOCNO>
Microscopic entropy of the most general four-dimensional BPS black hole


  In a recent paper we have given the macroscopic and microscopic description
of the generating solution of toroidally compactified string theory BPS black
holes. In this note we compute its corresponding microscopic entropy. Since by
definition the generating solution is the most general solution modulo
U-duality transformations, this result allows for a description of the
fundamental degrees of freedom accounting for the entropy of any regular BPS
black holes of toroidally compactified string (or M) theory.

</DOC>
<DOC>
<DOCNO> 40517 </DOCNO>
K0s K0s Final State in Two-Photon Collisions and Implications for


  The K0s K0s final state in two-photon collisions is studied with the L3
detector at LEP. The mass spectrum is dominated by the formation of the
f_2'(1525) tensor meson in the helicity-two state with a two-photon width times
the branching ratio into K Kbar of 76 +- 6 +- 11 eV. A clear signal for the
formation of the f_J(1710) is observed and it is found to be dominated by the
spin-two helicity-two state. No resonance is observed in the mass region around
2.2 GeV and an upper limit of 1.4 eV at 95% C.L. is derived for the two-photon
width times the branching ratio into K0s K0s for the glueball candidate
xi(2230).

</DOC>
<DOC>
<DOCNO> 70212 </DOCNO>
Measuring MSSM CP-violating Phases through Spin Correlated


  We provide a detailed analysis of the supersymmetric tri-lepton signals for
sparticle searches at the Tevatron in the minimal supersymmetric standard model
with general CP-violating phases but without flavor mixing among sfermions of
different generation. The stringent experimental constraints on the
CP-violating phases from the electron and neutron electric dipole moments are
included in the analysis for two exemplary scenarios of the SUSY parameters;
one with decoupled first two generation sfermions and the other with
non-decoupled sfermions. In both scenarios, the production cross section and
the branching fractions of the leptonic chargino and neutralino decays are
sensitive to CP-violating phases. The production-decay spin correlations lead
to several non-trivial CP-even observables such as the lepton invariant mass
distribution and the lepton angular distribution, and several interesting T-odd
(CP-odd) momentum triple products. The possibility of measuring the
CP-violating phases directly through those T-odd observables is investigated in
detail.

</DOC>
<DOC>
<DOCNO> 118302 </DOCNO>
A Single Circumbinary Disk in the HD 98800 Quadruple System


  We present sub-arcsecond thermal infrared imaging of HD 98800, a young
quadruple system composed of a pair of low-mass spectroscopic binaries
separated by 0.8'' (38 AU), each with a K-dwarf primary. Images at wavelengths
ranging from 5 to 24.5 microns show unequivocally that the optically fainter
binary, HD 98800B, is the sole source of a comparatively large infrared excess
upon which a silicate emission feature is superposed. The excess is detected
only at wavelengths of 7.9 microns and longer, peaks at 25 microns, and has a
best-fit black-body temperature of 150 K, indicating that most of the dust lies
at distances greater than the orbital separation of the spectroscopic binary.
We estimate the radial extent of the dust with a disk model that approximates
radiation from the spectroscopic binary as a single source of equivalent
luminosity. Given the data, the most-likely values of disk properties in the
ranges considered are R_in = 5.0 +/- 2.5 AU, DeltaR = 13+/-8 AU, lambda_0 =
2(+4/-1.5) microns, gamma = 0+/-2.5, and sigma_total = 16+/-3 AU^2, where R_in
is the inner radius, DeltaR is the radial extent of the disk, lambda_0 is the
effective grain size, gamma is the radial power-law exponent of the optical
depth, tau, and sigma_total is the total cross-section of the grains. The range
of implied disk masses is 0.001--0.1 times that of the moon. These results show
that, for a wide range of possible disk properties, a circumbinary disk is far
more likely than a narrow ring.

</DOC>
<DOC>
<DOCNO> 9961 </DOCNO>
Scissors mode in a superfluid Fermi gas


  We evaluate the frequencies of scissors modes for density and concentration
fluctuations in a vapour of fermionic atoms placed in two hyperfine levels
inside a spherical harmonic trap. Both the superfluid and the normal state are
considered, with inclusion of the interactions at the random-phase level. Two
main results are obtained: (i) the transition to the superfluid state is
signalled by the disappearance of soft transverse modes of the normal fluid in
the collisionless regime and (ii) the eigenfrequency of the density
fluctuations in the superfluid coincides with that of the normal fluid in the
collisional regime. The latter property is related to the opening of the gap in
the single-pair spectrum.

</DOC>
<DOC>
<DOCNO> 120055 </DOCNO>
Pre-main sequence binaries with aligned disks ?


  We present the results of a study performed with the goal to investigate
whether low-mass pre-main sequence binary stars are formed by multiple
fragmentation or via stellar capture. If binaries form preferentially by
fragmentation, we expect their disks to be co-planar. On the other hand, the
capture scenario will lead to a random distribution of disk orientations. We
performed near-infrared polarization measurements of 49 young close binary
stars in the K band with SOFI at the NTT. The near-infrared excess radiation of
the targets mostly point to the presence of disks. For a major fraction of the
sample, evidence for disks is also obvious from other features (outflows, jets,
Herbig-Haro objects). We derived the disk orientation from the orientation of
the polarization vector of both components of each binary. This statistical
study allows to test which hypothesis (co-planarity, random orientation) is
consistent with the observed distribution of polarimetric

</DOC>
<DOC>
<DOCNO> 12744 </DOCNO>
Quasiparticles in the multicomponenet Zhang-Hansson-Kivelson model


  We study the vortex solutions in a multicomponent Zhang-Hansson-Kivelson
model for the fractional quantum Hall effect, at the self-dual point. Vortices
with minimal free energy represent Laughlin quasiholes. We find at least two
classes of solutions, distinguished by their global invariance, or by the
number of conserved charges.

</DOC>
<DOC>
<DOCNO> 9631 </DOCNO>
Quantum fluctuation-dissipation theorem: a time domain formulation


  A time-domain formulation of the equilibrium quantum fluctuation-dissipation
theorem (FDT) in the whole range of temperatures is presented. In the classical
limit, the FDT establishes a proportionality relation between the dissipative
part of the linear response function and the derivative of the corresponding
equilibrium correlation function. At zero temperature, the FDT takes the form
of Hilbert transform relations between the dissipative part of the response
function and the corresponding symmetrized equilibrium correlation function,
which allows to establish a connection with analytic signal theory. The
time-domain formulation of the FDT is especially valuable when
out-of-equilibrium dynamics is concerned, as it is for instance the case in the
discussion of aging phenomena.

</DOC>
<DOC>
<DOCNO> 10766 </DOCNO>
Quantum Coherence and Decoherence in Magnetic Nanostructures


  The prospect of developing magnetic qubits is discussed. The first part of
the article makes suggestions on how to achieve the coherent quantum
superposition of spin states in small ferromagnetic clusters, weakly
uncompensated antiferromagnetic clusters, and magnetic molecules. The second
part of the article deals with mechanisms of decoherence expected in magnetic
systems. Main decohering effects are coming from nuclear spins and magnetic
fields. They can be reduced by isotopic purification and superconducting
shielding. In that case the time reversal symmetry of spin Hamiltonians makes
spin-phonon coupling ineffective in destroying quantum coherence.

</DOC>
<DOC>
<DOCNO> 99724 </DOCNO>
Making non-trivially associated tensor categories from left coset


  The paper begins by giving an algebraic structure on a set of coset
representatives for the left action of a subgroup on a group. From this we
construct a non-trivially associated tensor category. Also a double
construction is given, and this allows the construction of a non-trivially
associated braided tensor category. In this category we explicitly reconstruct
a braided Hopf algebra, whose representations comprise the category itself.

</DOC>
<DOC>
<DOCNO> 84760 </DOCNO>
Metric-affine gravity and the Nester-Witten 2-form


  In this paper we redefine the well-known metric-affine Hilbert Lagrangian in
terms of a spin-connection and a spin-tetrad. On applying the Poincar\'e-Cartan
method and using the geometry of gauge-natural bundles, a global gravitational
superpotential is derived. On specializing to the case of the Kosmann lift, we
recover the result originally found by Kijowski (1978) for the metric (natural)
Hilbert Lagrangian. On choosing a different, suitable lift, we can also recover
the Nester-Witten 2-form, which plays an important role in the energy
positivity proof and in many quasi-local definitions of mass.

</DOC>
<DOC>
<DOCNO> 100490 </DOCNO>
Invariants of knot diagrams and relations among Reidemeister moves


  In this paper a classification of Reidemeister moves, which is the most
refined, is introduced. In particular, this classification distinguishes some
$\Omega_3$-moves that only differ in how the three strands that are involved in
the move are ordered on the knot.
 To transform knot diagrams of isotopic knots into each other one must in
general use $\Omega_3$-moves of at least two different classes. To show this,
knot diagram invariants that jump only under $\Omega_3$-moves are introduced.
 Knot diagrams of isotopic knots can be connected by a sequence of Reidemeister
moves of only six, out of the total of 24, classes. This result can be applied
in knot theory to simplify proofs of invariance of diagrammatical knot
invariants. In particular, a criterion for a function on Gauss diagrams to
define a knot invariant is presented.

</DOC>
<DOC>
<DOCNO> 11438 </DOCNO>
Skyrmions in the Quantum Hall effect and noncommutative solitons


  It has been recently shown that solitons are fundamental classical solutions
of non-commutative field theories. We reconsider this issue from the standpoint
of the Hall effect and identify some solutions with known solutions in the
integer Hall effect with no Zeeman coupling.

</DOC>
<DOC>
<DOCNO> 80764 </DOCNO>
Can Merons Describe Confinement?


  Merons, conjectured as a semiclassical mechanism for color confinement in
QCD, are topological charge-1/2, singular solutions to the classical Yang-Mills
equations of motion. I will discuss how lattice techniques can extend the study
of merons to nonsingular stationary solutions without destroying properties
believed to be essential for confinement, and how zero modes can be used to
identify these gauge field configurations in stochastic evaluations of the
lattice QCD path integral.

</DOC>
<DOC>
<DOCNO> 84997 </DOCNO>
Stewart-Lyth Inverse Problem


  In this paper the Stewart-Lyth inverse problem is introduced. It consists of
solving two non-linear differential equations for the first slow-roll parameter
and finding the inflaton potential. The equations are derived from the
Stewart--Lyth equations for the scalar and tensorial perturbations produced
during the inflationary period. The geometry of the phase planes transverse to
the trajectories is analyzed, and conclusions about the possible behaviour for
general solutions are drawn.

</DOC>
<DOC>
<DOCNO> 70270 </DOCNO>
Fate of the Sterile Neutrino


  In light of recent Super-Kamiokande data and global fits that seem to exclude
both pure \nu_\mu \to \nu_s oscillations of atmospheric neutrinos and pure
\nu_e \to \nu_s oscillations of solar neutrinos (where \nu_s is a sterile
neutrino), we reconsider four-neutrino models to explain the LSND, atmospheric,
and solar neutrino oscillation indications. We argue that the solar data, with
the exception of the ^{37}Cl results, are suggestive of \nu_e \to \nu_s
oscillations that average to a probability of approximately 1/2. In this
interpretation, with two pairs of nearly degenerate mass eigenstates separated
by order 1 eV, the day-night asymmetry, seasonal dependence, and energy
dependence for ^8B neutrinos should be small. Alternatively, we find that
four-neutrino models with one mass eigenstate widely separated from the others
(and with small sterile mixings to active neutrinos) may now be acceptable in
light of recently updated LSND results; the ^{37}Cl data can be accommodated in
this model. For each scenario, we present simple four-neutrino mixing matrices
that fit the stated criterion and discuss future tests.

</DOC>
<DOC>
<DOCNO> 121574 </DOCNO>
On ionisation effects and abundance ratios in damped Lyman-alpha systems


  The similarity between observed velocity structures of Al III and singly
ionised species in damped Lyman-alpha systems (DLAs) suggests the presence of
ionised gas in the regions where most metal absorption lines are formed.
  To explore the possible implications of ionisation effects we construct a
simplified two-region model for DLAs consisting of an ionisation bounded region
with an internal radiation field and a neutral region with a lower metal
content. Within this framework we find that ionisation effects are important.
If taken into account, the element abundance ratios in DLAs are quite
consistent with those observed in Milky Way stars and in metal-poor H II
regions in blue compact dwarf galaxies. In particular we cannot exclude the
same primary N origin in both DLAs and metal-poor galaxies. From our models no
dust depletion of heavy elements needs to be invoked; little depletion is
however not excluded.

</DOC>
<DOC>
<DOCNO> 40344 </DOCNO>
Observation of color-transparency in diffractive dissociation of pions


  We have studied the diffractive dissociation into di-jets of 500 GeV/c pions
scattering coherently from carbon and platinum targets. Extrapolating to
asymptotically high energies (where t_{min} approaches 0) we find that when the
per-nucleus cross-section for this process is parameterized as $\sigma =
\sigma_0 A^{\alpha}, \alpha$ has values near 1.6, the exact result depending on
jet transverse momentum. These values are in agreement with those predicted by
theoretical calculations of color-transparency.

</DOC>
<DOC>
<DOCNO> 68737 </DOCNO>
On the miracle of the Coleman-Glashow and other baryon mass formulas


  Due to a new measurement of the Xi(0) mass,the Coleman-Glashow formula for
the baryon octet e.m. masses (derived using unbroken SU(3) is satisfied to an
extraordinary level of precision.The same unexpected precision exists for the
Gell-Mann Okubo formula and for its octet-decuplet extension
(G.Morpurgo,Phys.Rev.Lett. 68(1992)139).We show that the old question "why do
they work so well?" is now answered by the general parameterization method.

</DOC>
<DOC>
<DOCNO> 101374 </DOCNO>
Functoriality and Morita equivalence of operator algebras and Poisson


  It is well known that a measured groupoid G defines a von Neumann algebra
W*(G), and that a Lie groupoid G canonically defines both a C*-algebra C*(G)
and a Poisson manifold A*(G). We show that the maps G -> W*(G), G -> C*(G) and
G -> A*(G) are functorial with respect to suitable categories. In these
categories Morita equivalence is isomorphism of objects, so that these maps
preserve Morita equivalence.

</DOC>
<DOC>
<DOCNO> 11113 </DOCNO>
Quantum-Information Processing with Semiconductor Macroatoms


  An all optical implementation of quantum information processing with
semiconductor macroatoms is proposed. Our quantum hardware consists of an array
of semiconductor quantum dots and the computational degrees of freedom are
energy-selected interband optical transitions. The proposed quantum-computing
strategy exploits exciton-exciton interactions driven by ultrafast sequences of
multi-color laser pulses. Contrary to existing proposals based on charge
excitations, the present all-optical implementation does not require the
application of time-dependent electric fields, thus allowing for a
sub-picosecond, i.e. decoherence-free, operation time-scale in realistic
state-of-the-art semiconductor nanostructures.

</DOC>
<DOC>
<DOCNO> 151312 </DOCNO>
Quotient Construction of 't Hooft's Quantum Equivalence Classes


  Most recently 't Hooft has postulated (G 't Hooft, Class. Quant. Grav. 16
(1999) 3263-3279) that quantum states at the ``atomic scale''can be understood
as equivalence classes of primordial states governed by a dissipative
deterministic theory underlying quantum theory at the ``Planck scale''.
Defining invariant subspaces clearly for primordial states according to a given
evolution, we mathematically re-formulate 't Hooft's theory as a quotient space
construction with the time-reversible evolution operator induced naturally.
With this observation and some analysis, 't Hooft's theory is generalized
beyond his case where the evolution at the ``Planck scale'' is periodic or the
time is discrete. We also give a novel illustration that the Fock space of
quantum oscillator could follow from the quotient space construction for
certain primordial states obeying non-reversible evolution governed by a
non-Hermitian Hamiltonian.

</DOC>
<DOC>
<DOCNO> 69432 </DOCNO>
A Possible Arena for Searching New Physics - the $\Gamma(D^0 \to \rho^0


  We propose to investigate flavour changing neutral currents in the $c \to u
\gamma$ transition through the measurement of the difference between $\Gamma
(D^0 \to \rho^0 \gamma)$ and $\Gamma (D^0 \to \omega \gamma)$. This is based on
the observation that $D^0 \to (d \bar d) \gamma$ is due to long distance
physics while $D^0 \to (u \bar u) \gamma$ arises from the $c \to u \gamma$
transition. The effect of $\rho - \omega$ mixing is included. A difference in
the decay widths of more than about 30% would be indicative of new physics.

</DOC>
<DOC>
<DOCNO> 101811 </DOCNO>
On the Galois Theory of Grothendieck


  In this paper we deal with Grothendieck's interpretation of Artin's
interpretation of Galois's Galois Theory (and its natural relation with the
fundamental group and the theory of coverings) as he developed it in Expose V,
section 4, ``Conditions axiomatiques d'une theorie de Galois'' in the SGA1
1960/61.
  This is a beautiful piece of mathematics very rich in categorical concepts,
and goes much beyond the original Galois's scope (just as Galois went much
further than the non resubility of the quintic equation). We show explicitly
how Grothendieck's abstraction corresponds to Galois work.
  We introduce some axioms and prove a theorem of characterization of the
category (topos) of actions of a discrete group. This theorem corresponds
exactly to Galois fundamental result. The theorem of Grothendieck characterizes
the category (topos) of continuous actions of a profinite topological group. We
develop a proof of this result as a "passage into the limit'' (in an inverse
limit of topoi) of our theorem of characterization of the topos of actions of a
discrete group. We deal with the inverse limit of topoi just working with an
ordinary filtered colimit (or union) of the small categories which are their
(respective) sites of definition.
  We do not consider generalizations of Grothendieck's work, except by
commenting briefly in the last section how to deal with the prodiscrete (not
profinite) case. We also mention the work of Joyal-Tierney, which falls
naturally in our discussion.
  There is no need of advanced knowledge of category theory to read this paper,
exept for the comments in the last section.

</DOC>
<DOC>
<DOCNO> 120754 </DOCNO>
Gas metallicities and early evolution of distant radiogalaxies


  By modeling the rich emission line spectra of a sample of high redshift
(HzRG, z\sim 2.5) radio galaxies we find that solar and supersolar
metallicities are common in the extended gas of these objects. Our models and
the comparison with high redshift quasars suggest that HzRG at z\sim 2.5 are
associated with intense star formation activity. This is consistent with
chemical evolution models for giant ellipticals and it supports the idea that
distant powerful radio galaxies are progenitors of giant ellipticals. We might
be witnessing different evolutive status in different objects.

</DOC>
<DOC>
<DOCNO> 121528 </DOCNO>
The HST snapshot survey of the B2 sample of low luminosity


  A Hubble Space Telescope snapshot survey of the B2 sample of low luminosity
radio galaxies has, at present, produced V and I images of 41 objects. Together
with 16 images of B2 sources taken from the HST archive, there are now high
resolution optical data for 57 % of the sample. All host galaxies are luminous
ellipticals, except one which is a spiral galaxy, while another one turns out
to be a misidentification.
  We present an album of the images of the B2 radio galaxies observed so far,
and give a brief description of the optical morphology of the galaxies. Dust
features (in the form of disks, lanes or irregular patches) are seen in most of
the galaxies of the sample, 58 %. Compact optical cores are also very common
(18/57). A preliminary analysis has revealed the presence of an optical jet in
three objects, indicating they can be detected in a sizeable percentage in
these low luminosity radio sources. Brightness profiles of dust-free galaxies
are well represented by a Nuker law and all shows the existence of a resolved
shallow cusp.

</DOC>
<DOC>
<DOCNO> 100836 </DOCNO>
Good Stein Neighborhood Bases and Regularity of the d-bar Neumann


  We show that if the closure of a smooth pseudoconvex domain admits a
"sufficiently nice" Stein neighborhood basis, then the d-bar Neumann problem on
the domain is globally regular.

</DOC>
<DOC>
<DOCNO> 100294 </DOCNO>
On subgroups of minimal topological groups


  The {\it Roelcke uniformity} on a topological group is the greatest lower
bound of the left and right uniformities. A group is {\it Roelcke-precompact}
if it is precompact with respect to the Roelcke uniformity. Many naturally
arising non-abelian topological groups are Roelcke-precompact and hence have a
natural compactification. We use such compactifications to prove that the
groups of isometries of generalized Urysohn metric spaces are minimal. A
topological group is {\it minimal} if it does not admit a strictly coarser
Hausdorff group topology. We show that every topological group is a subgroup of
a minimal topologically simple Roelcke-precompact group.

</DOC>
<DOC>
<DOCNO> 100552 </DOCNO>
On isomorphisms of standard operator algebras


  The aim of this paper is to show that between standard operator algebras
every bijective map with a certain multiplicativity property related to Jordan
triple isomorphisms of associative rings is automatically additive.

</DOC>
<DOC>
<DOCNO> 118268 </DOCNO>
A Theoretical Review of Axion


  It is emphasized that the existence of a very light axion is consistent with
the strong CP invariance and cosmological and astrophysical constraints. The
attempt to embed the very light axion in superstring models is discussed.

</DOC>
<DOC>
<DOCNO> 116539 </DOCNO>
Breit interaction in heavy atoms


  In this letter we discuss how to include Breit interaction in calculations of
low-energy properties of heavy atoms in accurate and effective way. In order to
illustrate our approach we give some results for Cs and Tl.

</DOC>
<DOC>
<DOCNO> 81019 </DOCNO>
Helicity modulus as renormalized coupling in the O(3) sigma-model


  For the family of O(n) invariant nonlinear sigma-models we consider boundary
conditions that are periodic up to an O(n) rotation. The helicity modulus is
related to the change in free energy under variations of the corresponding
angle. It defines a nonperturbative finite volume running coupling similar to
the Schr"odinger functional for QCD. For the two-dimensional O(3)-model we
investigate this quantity by analytical and numerical techniques. We establish
its universal continuum relation to the finite volume massgap coupling at all
scales and coupling strengths.

</DOC>
<DOC>
<DOCNO> 39960 </DOCNO>
The Parton Content of the Photon


  The structure of the photon is studied in photon-photon collisions at LEP.
New measurements have become available exploring the structure function F2g of
the photon to the lowest values of x yet, where the hadronic component of the
photon is most important. Inclusive cross sections for charged D* have been
measured as a function of their transverse momenta and are used to test the
validity of perturbative QCD in NLO in this region. The total charm quark
production cross section is extracted. For the first time the inclusive
production of D* mesons in deep inelastic electron-photon scattering has been
used to extract the charm structure function of the photon. A first sign of
beauty production in photon-photon collisions is reported.

</DOC>
<DOC>
<DOCNO> 69422 </DOCNO>
Improved Unitarized Heavy Baryon Chiral Perturbation Theory for $\pi N $


  We show how the unitarized description of pion nucleon scattering within
Heavy Baryon Chiral Perturbation Theory can be considerably improved, by a
suitable reordering of the expansion over the nucleon mass. Within this
framework, the $\Delta$ resonance and its associated pole can be recovered from
the chiral parameters obtained from low-energy determinations. In addition, we
can obtain a good description of the six $S$ and $P$ wave phase shifts in terms
of chiral parameters with a natural size and compatible with the Resonance
Saturation Hypothesis.

</DOC>
<DOC>
<DOCNO> 12775 </DOCNO>
Aharonov-Bohm effect of excitons in nano-rings


  The magnetic field effects on excitons in an InAs nano-ring are studied
theoretically. By numerically diagonalizing the effective-mass Hamiltonian of
the problem, which can be separated into terms in centre-of-mass and relative
coordinates, we calculate the low-lying exciton energy levels and oscillator
strengths as a function of the width of the ring and the strength of the
external magnetic field. The analytical results are obtained for a narrow-width
nano-ring in which the radial motion is the fastest one and adiabatically
decoupled from the azimuthal motions. It is shown that in the presence of
Coulomb correlation, the so called Aharonov-Bohm effect of excitons exists in a
finite (but small) width nano-ring. However, when the ring width becomes large,
the non-simply-connected geometry of nano-rings is destroyed and in turn yields
the suppression of Aharonov-Bohm effect. The conditional probability
distribution calculated for the low-lying exction states allows identification
of the presence of Aharonov-Bohm effect. The linear optical susceptibility is
also calculated as a function of the magnetic field, to be confronted with the
future measurements of optical emission experiments on InAs nano-rings.

</DOC>
<DOC>
<DOCNO> 150998 </DOCNO>
Supersymmetric Dirac-Born-Infeld theory in noncommutative space


  We present a supersymmetric version of Dirac-Born-Infeld (DBI) theory in
noncommutative space-time, both for Abelian and non-Abelian gauge groups. We
show, using the superfield formalism, that the definition of a certain ordering
with respect to the * product leads naturally to a DBI action both in the U(1)
as well as in the U(N) case. BPS equations are analysed in this context and
properties of the resulting theory are discussed.

</DOC>
<DOC>
<DOCNO> 8990 </DOCNO>
Microscopic Scenario for Striped Superconductors


  We argue that the superconducting state found in high-$T_c$ cuprates is
inhomogeneous with a corresponding inhomogeneous superfluid density. We
introduce two classes of microscopic models which capture the magnetic and
superconducting properties of these strongly correlated materials. We start
from a generalized t-J model, in which appropriate inhomogeneous terms mimic
stripes. We find that inhomogeneous interactions that break magnetic symmetries
are essential to induce substantial pair binding of holes in the thermodynamic
limit. We argue that this type of model reproduces the ARPES and neutron
scattering data seen experimentally.

</DOC>
<DOC>
<DOCNO> 118626 </DOCNO>
The Predicted Signature of Neutrino Emission in Observations of


  Pre-white dwarf (PWD) star evolution can be driven by energy losses from
neutrino interactions in the core. Unlike solar neutrinos, these are not the
by-product of nuclear fusion, but instead result from electron scattering
processes in the hot, dense regions of the PWD core. We show that the observed
rate of period change in cool PWD pulsators will constrain neutrino emission in
their cores, and we identify appropriate targets for future observation. Such a
measurement will tell us whether the theories of lepton interactions correctly
describe the production rates and therefore neutrino cooling of PWD evolution.
This would represent the first test of standard lepton theory in dense plasma.

</DOC>
<DOC>
<DOCNO> 116288 </DOCNO>
The Hydration Number of Li+ in Liquid Water


  A theoretical treatment based upon the quasi-chemical theory of solutions
predicts the most probable number of water neighbors in the inner shell of a
Li+ ion in liquid water to be four. The instability of a six water molecule
inner sphere complex relative to four-coordinated structures is confirmed by an
`ab initio' molecular dynamics calculation. A classical Monte Carlo simulation
equilibrated 26 water molecules with a rigid six-coordinated Li(H2O)6+ complex
with periodic boundary conditions in aqueous solution. With that initial
configuration for the molecular dynamics, the six-coordinated structure relaxed
into four-coordinated arrangements within 112 fs and stabilized. This
conclusion differs from prior interpretations of neutron and X-ray scattering
results on aqueous solutions.

</DOC>
<DOC>
<DOCNO> 122957 </DOCNO>
Optical Gravitational Lensing Experiment. OGLE 2000-BUL-43: A


  We present the photometry and theoretical models for a Galactic bulge
microlensing event OGLE-2000-BUL-43. The event is very bright with I=13.54 mag,
and has a very long time scale, t_E=156 days. The long time scale and its light
curve deviation from the standard shape strongly suggest that it may be
affected by the parallax effect. We show that OGLE-2000-BUL-43 is the first
discovered microlensing event, in which the parallax distortion is observed
over a period of 2 years. Difference Image Analysis (DIA) using the PSF
matching algorithm of Alard & Lupton enabled photometry accurate to 0.5%. All
photometry obtained with DIA is available electronically. Our analysis
indicates that the viewing condition from a location near Jupiter will be
optimal and can lead to magnifications ~ 50 around January 31, 2001. These
features offer a great promise for resolving the source (a K giant) and
breaking the degeneracy between the lens parameters including the mass of the
lens, if the event is observed with the imaging camera on the Cassini space
probe.

</DOC>
<DOC>
<DOCNO> 170536 </DOCNO>
Quantum Gambling Using Two Nonorthogonal States


  We give a (remote) quantum gambling scheme that makes use of the fact that
quantum nonorthogonal states cannot be distinguished with certainty. In the
proposed scheme, two participants Alice and Bob can be regarded as playing a
game of making guesses on identities of quantum states that are in one of two
given nonorthogonal states: if Bob makes a correct (an incorrect) guess on the
identity of a quantum state that Alice has sent, he wins (loses). It is shown
that the proposed scheme is secure against the nonentanglement attack. It can
also be shown heuristically that the scheme is secure in the case of the
entanglement attack.

</DOC>
<DOC>
<DOCNO> 150461 </DOCNO>
Effects of Trilinear Term in Softly Broken N=1 Supersymmetric QCD


  Softly broken dual magnetic theory of N=1 supersymmetric SU(N_c) QCD with N_f
flavours is investigated with the inclusion of trilinear coupling term of
scalar fields in the case of N_f>N_c+1. It is found that the trilinear soft
supersymmetric breaking term greatly change the phase and the vacuum structure.

</DOC>
<DOC>
<DOCNO> 101469 </DOCNO>
q-Analogs of symmetric function operators


  For any homomorphism V on the space of symmetric functions, we introduce an
operation which creates a q-analog of V. By giving several examples we
demonstrate that this quantization occurs naturally within the theory of
symmetric functions. In particular, we show that the Hall-Littlewood symmetric
functions are formed by taking this q-analog of the Schur symmetric functions
and the Macdonald symmetric functions appear by taking the q-analog of the
Hall-Littlewood symmetric functions in the parameter t. This relation is then
used to derive recurrences on the Macdonald q,t-Kostka coefficients.

</DOC>
<DOC>
<DOCNO> 84580 </DOCNO>
Classical Geometry from a Physical State in Canonical Quantum Gravity


  We construct a weave state which approximates a degenerate 3-metric of rank 2
at large scales. It turns out that a non-degenerate metric region can be
evolved from this degenerate metric by the classical Ashtekar equations, hence
the degeneracy of 3-metrics is not preserved by the evolution of Ashtekar's
equations. As the s-knot state corresponding to this weave is shown to solve
all the quantum constraints in loop quantum gravity, a physical state in
canonical quantum gravity is related to the familiar classical geometry.

</DOC>
<DOC>
<DOCNO> 69840 </DOCNO>
Methods for the nonperturbative approximation of form factors and


  Methods are described for the nonperturbative calculation of wave functions
and scattering amplitudes in light-cone quantization. Form factors are computed
from the boost-invariant wave functions, which appear as coefficients in a
Fock-state expansion of the field-theoretic eigenstate. A technique is proposed
for calculating scattering amplitudes from matrix elements of a T operator
between such composite-particle eigenstates.

</DOC>
<DOC>
<DOCNO> 99312 </DOCNO>
Conormal modules via Primitive ideals


  The main object of this note is to study the conormal module $M$ and the
computation of the second symbolic power $\bar I^{(2)}$ of an ideal $\bar I$ in
the residue ring $R/H$ of a polynomial ring $R$ over a field of characteristic
zero. The torsion part $T(M)$ of $M$ and the torsion free module $M/T(M)$ are
expressed by the primitive ideal of $I$ relative to $H$. Two characterizations
for $M/T(M)$ to be free are proved. Some immediate applications are worked out.

</DOC>
<DOC>
<DOCNO> 123314 </DOCNO>
Understanding Galactic Black Hole Candidate GRS 1915+105


  We interpret observed features of the black hole candidate GRS1915+105 in the
light of the advective flow paradigm. The light curve of this black hole is
seen to be of four classes, Soft, Hard, Semi-Soft and Intermediate. Each class
can display more than one type of light curve making altogether twelve or more
types of light curves. In each type, the mode of accretion may be one or more
of three types: which we identify as HW (hard state with winds), CC (Compton
cooling) and EA (enhanced accretion) respectively. Apart from these three
states there are two more fundamental states in a black hole accretion which
are soft and hard states. We also find that winds and outflows could soften
spectra in hard states and the enhanced accretion could harden the soft states.
These are observed in the spectra of GRS 1915+105. Generally, we find that
advective flow paradigm can satisfactorily explain all the features of the
enigmatic black hole GRS 1915+105.

</DOC>
<DOC>
<DOCNO> 68084 </DOCNO>
How precisely can we determine the pion-nucleon coupling constant from


  The isovector GMO sum rule for zero energy forward pion-nucleon scattering is
critically studied to obtain the charged pion-nucleon coupling constant using
the precise negatively charged pion-proton and pion-deuteron scattering lengths
deduced recently from pionic atom experiments. This direct determination leads
to a pseudoscalar charged pion-nucleon coupling constant of 14.23 +- 0.09
(statistic) +- 0.17 (systematic). We obtain also accurate values for the
pion-nucleon scattering lengths.

</DOC>
<DOC>
<DOCNO> 119665 </DOCNO>
The Nature of the Halo Population of NGC 5128 Resolved with NICMOS on


  We present the first infrared color-magnitude diagram (CMD) for the halo of a
giant elliptical galaxy. The CMD for the stars in the halo of NGC 5128
(Centaurus A) was constructed from HST NICMOS observations of the WFPC2 CHIP-3
field of Soria et al. (1996) to a 50% completeness magnitude limit of
[F160W]=23.8. This field is located at a distance of 08'50" (~9 kpc) south of
the center of the galaxy. The luminosity function (LF) shows a marked
discontinuity at [F160W]=20.0. This is 1-2 mag above the tip of the red giant
branch (TRGB) expected for an old population (~12 Gyr) at the distance modulus
of NGC 5128. We propose that the majority of stars above the TRGB have
intermediate ages (~2 Gyr), in agreement with the WFPC2 observations of Soria
et al. (1996). Five stars with magnitudes brighter than the LF discontinuity
are most probably due to Galactic contamination. The weighted average of the
mean giant branch color above our 50% completeness limit is
[F110W]-[F160W]=1.22+-0.08 with a dispersion of 0.19 mag. From our
artificial-star experiments we determine that the observed spread in color is
real, suggesting a real spread in metallicity. We estimate the lower and upper
bounds of the stellar metallicity range by comparisons with observations of
Galactic star clusters and theoretical isochrones. Assuming an old population,
we find that, in the halo field of NGC 5128 we surveyed, stars have
metallicities ranging from roughly 1% of solar at the blue end of the color
spread to roughly solar at the red end, with a mean of [Fe/H]=-0.76 and a
dispersion of 0.44 dex.

</DOC>
<DOC>
<DOCNO> 102525 </DOCNO>
The generalized Borwein conjecture. I. The Burge transform


  Given an arbitrary ordered pair of coprime integers (a,b) we obtain a pair of
identities of the Rogers--Ramanujan type. These identities have the same
product side as the (first) Andrews--Gordon identity for modulus 2ab\pm 1, but
an altogether different sum side, based on the representation of (a/b-1)^{\pm
1} as a continued fraction. Our proof, which relies on the Burge transform,
first establishes a binary tree of polynomial identities. Each identity in this
Burge tree settles a special case of Bressoud's generalized Borwein conjecture.

</DOC>
<DOC>
<DOCNO> 122160 </DOCNO>
Cosmic Gamma-Ray Bursts as a Probe of Star Formation History


  The cosmic gamma-ray burst (GRB) formation rate, as derived from the
variability-luminosity relation for long-duration GRBs, is compared with the
cosmic star formation rate. If GRBs are related to the collapse of massive
stars, one expects the GRB rate to be approximately proportional to the star
formation rate. We found that these two rates have similar slopes at low
redshift. This suggests that GRBs do indeed track the star formation rate of
the Universe, which in turn implies that the formation rate of massive stars
that produce GRBs is proportional to the total star formation rate. It also
implies that we might be able to use GRBs as a probe of the cosmic star
formation rate at high redshift. We find that the cosmic star formation rate
inferred from the variability-luminosity relation increases steeply with
redshift at z > 3. This is in apparent contrast to what is derived from
measurements of the cosmic star formation rate at high redshift from optical
observations of field galaxies, suggesting that much high-z star formation is
being missed in the optical surveys, even after corrections for dust extinction
have been made.

</DOC>
<DOC>
<DOCNO> 12475 </DOCNO>
Occam factors and model-independent Bayesian learning of continuous


  Learning of a smooth but nonparametric probability density can be regularized
using methods of Quantum Field Theory. We implement a field theoretic prior
numerically, test its efficacy, and show that the data and the phase space
factors arising from the integration over the model space determine the free
parameter of the theory ("smoothness scale") self-consistently. This persists
even for distributions that are atypical in the prior and is a step towards a
model-independent theory for learning continuous distributions. Finally, we
point out that a wrong parameterization of a model family may sometimes be
advantageous for small data sets.

</DOC>
<DOC>
<DOCNO> 9717 </DOCNO>
Scaling and Persistence in the Two-Dimensional Ising Model


  The spatial distribution of persistent spins at zero-temperature in the pure
two-dimensional Ising model is investigated numerically. A persistence
correlation length, $\xi (t)\sim t^Z$ is identified such that for length scales
$r<<\xi (t)$ the persistent spins form a fractal with dimension $d_f$; for
length scales $r>>\xi (t)$ the distribution of persistent spins is homogeneous.
The zero-temperature persistence exponent, $\theta$, is found to satisfy the
scaling relation $\theta = Z(2-d_f)$ with $\theta =0.209\pm 0.002, Z=1/2$ and
$d_f\sim 1.58$.

</DOC>
<DOC>
<DOCNO> 83256 </DOCNO>
Distorted English Alphabet Identification : An application of Difference


  The difference-boosting algorithm is used on letters dataset from the UCI
repository to classify distorted raster images of English alphabets. In
contrast to rather complex networks, the difference-boosting is found to
produce comparable or better classification efficiency on this complex problem.

</DOC>
<DOC>
<DOCNO> 152489 </DOCNO>
Complex geometry of conifolds and 5-brane wrapped on 2-sphere


  We investigate solutions of type II supergravity which have the product R^4 x
M^6 structure with non-compact M^6 factor and which preserve at least four
supersymmetries. In particular, we consider various conifolds and the N=1
supersymmetric NS5-brane wrapped on 2-sphere solution recently discussed in
hep-th/0008001. In all of these cases, we explicitly construct the complex
structures, and the Kaehler and parallel (3,0) forms of the corresponding M^6.
In addition, we verify that the above solutions preserve, respectively, eight
and four supersymmetries of type II theory. We also demonstrate that the
ordinary and fractional D3-brane solutions on singular, resolved and deformed
conifolds, and the (S-dual of) NS5-brane wrapped on 2-sphere can be obtained as
special cases from a universal ansatz for the supergravity fields and a single
1-d action governing their radial evolution. We show that like the 3-branes on
conifolds, the NS5-brane on 2-sphere background can be found as a solution of
first order system following from a superpotential.

</DOC>
<DOC>
<DOCNO> 119541 </DOCNO>
Eigenvector 1: An Optimal Correlation Space for Active Galactic Nuclei


  We identify a correlation space involving optical and UV emission line
parameters as well as the soft X-ray spectral index that provides optimal
discrimination between all principal classes of active galactic nuclei. Most of
the sources in our three high quality data samples show a strong
intercorrelation with narrow line Seyfert 1 (NLSy1) galaxies and steep spectrum
radio galaxies occupying opposite extrema in the space. NLSy1 sources show a
clear continuity with broader line sources indicating that they are not a
disjoint class of AGN as is sometimes suggested. We interpret the principal
intercorrelation in the parameter space as being driven by AGN luminosity to
black hole mass ratio (L/M prop. to the Eddington ratio). Source orientation no
doubt also plays an important role but it is not yet clear whether FWHM H beta
or CIV 1549 line shift is the better indicator. We tentatively identify two RQ
populations: an almost pure RQ population A with FWHM<=4000 and population B
which occupies the same parameter domain as the flat spectrum RL sources. A
possible interpretation sees Pop. A/NLSy1 as lower mass/high accretion rate
sources and Pop. B/RL sources the opposite.

</DOC>
<DOC>
<DOCNO> 69805 </DOCNO>
Strange quark matter in cosmic ray flux and exotic events


  There have been several reports of exotic nuclear fragments, with highly
unusual charge to mass ratio, in cosmic ray experiments. Although there exist
experimental uncertainties which make them, at best, only candidate "exotic"
events, it is important to understand what they could be, if they are
eventually confirmed. Among other possible explanations, some authors have
interpreted them to be lumps of strange quark matter (strangelets). A major
problem with such an interpretation is that to reach the earth's surface, they
must possess an unusually high penetrability through the terrestrial
atmosphere. We show that a recently proposed mechanism for the propagation of
strangelets through the earth's atmosphere, together with a proper account of
charge capture and ionisation loss, would solve this problem. We also argue
that this could lead to viable strategies for definitive detection of strange
quark matter in cosmic ray flux using a ground based large area array of
passive detectors.

</DOC>
<DOC>
<DOCNO> 121713 </DOCNO>
Euler, Hipparcos and the five dwarfs : Reconstructing star formation


  The unprecedented quality of recent colour-magnitude diagrams of resolved
stellar populations in nearby galaxies requires state-of-the-art techniques to
infer the star formation histories which gave rise to the observed
distributions. We have developed a maximum likelihood technique, which coupled
to a variational calculus allows us to make a robust, non-parametric
reconstruction of the evolution of the star formation rate. A full Bayesian
analysis is also applied to assess whether the best solutions found are also
good fits to the data. Applying this new method to WFPC2 observations of five
dSph galaxies of the Local Group, we find a wide variety of star formation
histories, with no particular epoch being dominant. In the case of the solar
neighbourhood observed by Hipparcos we infer, with an unprecedented resolution
of 50 Myr, its star formation history over the past 3 Gyr. The surprising
regularity of star formation episodes separated by some 0.5 Gyr could be
interpreted as the result of interactions with two spiral arms or the Galactic
bar. These bursts possibly trigger the formation of massive star clusters which
slowly dissolve into the galactic field.

</DOC>
<DOC>
<DOCNO> 40415 </DOCNO>
A Measurement of CP Violation in B0 Meson Decays with Belle


  We present a preliminary measurement of the Standard Model CP violation
parameter $\sin 2\phi_1$ using the Belle detector. A $6.2~{\rm fb}^{-1}$ sample
of events produced by the KEKB asymmetric $e^+e^-$ collider operating at the
$\Upsilon(4S)$ resonance is used. We report a preliminary result of $$\sin
2\phi_1=0.45^{+0.43}_{-0.44}({\rm stat})^{+0.07}_{-0.09}({\rm syst}).$$

</DOC>
<DOC>
<DOCNO> 170382 </DOCNO>
Quantum Mechanics and the Cookie Cutter Paradigm


  What has so far prevented us from decrypting quantum mechanics is the Cookie
Cutter Paradigm, according to which the world's synchronic multiplicity derives
from surfaces that carve up space in the manner of three-dimensional cookie
cutters. This insidious notion is shown to be rooted in our neurophysiological
make-up. An effort is made to liberate the physical world from this innate
fallacy.

</DOC>
<DOC>
<DOCNO> 9448 </DOCNO>
Topology dependent quantities at the Anderson transition


  The boundary condition dependence of the critical behavior for the three
dimensional Anderson transition is investigated. A strong dependence of the
scaling function and the critical conductance distribution on the boundary
conditions is found, while the critical disorder and critical exponent are
found to be independent of the boundary conditions.

</DOC>
<DOC>
<DOCNO> 9688 </DOCNO>
Non-quasiparticle microwave absorption in


  We show that a non-quasiparticle charge collective mode, in parallel and
coincident with the d-wave pair conductivity, leads to a quantitative
understanding of microwave surface impedance measurements on superconducting
$Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta}$. The analysis suggests an inhomogeneous
charge ground state in $Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta}$ and other HTS.

</DOC>
<DOC>
<DOCNO> 121786 </DOCNO>
The Warm Ionized Medium in the Milky Way and Other Galaxies


  Observations of the "Warm Ionized Medium" (or, equivalently, the "Diffuse
Ionized Gas") of the local ISM, the Perseus arm in the Milky Way, and also in
several other galaxies show strong [NII]6563 (~H-alpha in some cases) and
[SII]6717/[NII]6583 = 0.6 - 0.7 in all locations and objects. Other line ratios
(e.g., [O III]5007/H-beta) vary considerably. Simple photoionization models
reproduce the observed spectra, providing extra heating beyond that supplied by
photoionization is assumed (Reynolds, Haffner, & Tufte 1999). With observed
gas-phase abundances (not solar), the line ratios in the local arm at b = 0 deg
are fitted with no extra heating and (S/H) = 13 ppm (solar is 20 ppm). Local
gas observed at b = -35 deg requires extra heating of about gamma = 0.75, where
gamma is the extra heating in units of 10^{-25} erg H^{-1} s^{-1}. In the
Perseus arm, there are similar results, with a domposition consistent with the
Galactic abundance gradient. The requirements for NGC 891 are similar to the
Perseus arm: little or no extra heating at |z| = 1 kpc and gamma 3 at 2 kpc. In
NGC 891 there is also an increase of 5007/H-alpha with |z| that can only come
about if most of the ionizing radiation is supplied by stars with T~50000 K.
Either their radiation must propagate from the plane to high |z| through very
little intervening matter, or else the stars are located at high |z|. The total
power requirement of the extra heating is <15% of the photoionization power.
[O~II]3727/H-beta can serve as a useful diagnostic of extra heating, but
[S~III] 9065,9531/H-alpha is not useful in this regard.

</DOC>
<DOC>
<DOCNO> 123123 </DOCNO>
Are There ADAFs in Nearby Giant Elliptical Galaxies?


  Recently it has been suggested that the hard x-ray power-law tails exhibited
in the ASCA spectra of several nearby giant elliptical galaxies are caused by
low-radiative efficiency accretion flows (ADAFs) onto a massive black hole in
the centers of the galaxies. The estimated fluxes from these central ADAFs as
derived from the ASCA x-ray spectral analyses indicate that they may be visible
as x-ray point sources. We analyze archival ROSAT HRI images of three such
galaxies, NGCs 1399, 4636, and 4696, to determine whether point x-ray sources
consistent with ASCA-derived fluxes are present in the centers of the galaxies.
We find that the upper limit for the flux of a central point x-ray source in
each of these galaxies as determined by the ROSAT HRI data is only marginally
consistent with the predicted flux inferred from the ASCA spectra. We suggest
that although a central point source, such as a ADAF associated with a massive
black hole, cannot be completely ruled out, they can only account for a
fraction of the flux of the observed hard x-ray power law components.

</DOC>
<DOC>
<DOCNO> 152146 </DOCNO>
Covariant perturbation theory and the Randall-Sundrum picture


  The effective action for quantum fields on a $d$-dimensional spacetime can be
computed using a non local expansion in powers of the curvature. We show
explicitly that, for conformal fields and up to quadratic order in the
curvature, the non local effective action is equivalent to the $d+1$ action for
classical gravity in $AdS_{d+1}$ restricted to a $d-1$-brane. This generalizes
previous results about quantum corrections to the Newtonian potential and
provides an alternative method for making local a non-local effective action.
The equivalence can be easily understood by comparing the Kallen-Lehmann
decomposition of the classical propagator with the spectral representation of
the non local form factors in the quantum effective action.

</DOC>
<DOC>
<DOCNO> 152273 </DOCNO>
Null p-Branes


  The dissertation is devoted to the description and further investigation of
the properties of null p-branes.

</DOC>
<DOC>
<DOCNO> 14163 </DOCNO>
Thin-film effects on the surface stopping power of a free electron gas


  The electronic properties of thin films present quantum-size effects, which
are a consequence of the finite size of the system. Here we focus on the
investigation of these effects on the electronic energy loss of charged
particles moving parallel with thin metallic films. The energy loss is
calculated, within linear-response theory, from the knowledge of the
density-response function of the inhomogeneous electron system, which we
evaluate either in the random-phase approximation or with the use of an
adiabatic and local exchange-correlation kernel.

</DOC>
<DOC>
<DOCNO> 116881 </DOCNO>
Commissioning of the 1.4 Mev/u High Current Heavy Ion Linac at Gsi


  The disassembly of the Unilac prestripper linac of the Wideroe type took
place at the beginning of 1999. An increase of more than two orders of
magnitude in particle number for the most heavy elements in the SIS had to be
gained. Since that time the new High Current Injector (HSI) consisting of
H-type RFQ and DTL-structures for dual beam operation was installed and
successfully commissioned. The High Charge Injector (HLI) supplied the main
linac during that time. Simultaneously conditioning and running in of the
rf-transmitters and rf-structures were done. The HSI commissioning strategy
included beam investigation after each transport and acceleration section,
using a versatile diagnostic test stand. Results of the extensive commissioning
measurements (e.g. transverse emittance, bunch width, beam transmission) behind
LEBT, RFQ, Super Lens, IH tank I and II and stripping section will be
discussed. An 40Ar1+ beam coming from a MUCIS ion source was used to fill the
linac up to the theoretical space charge limit. Routine operation started in
November 1999.

</DOC>
<DOC>
<DOCNO> 68319 </DOCNO>
The geometry of atmospheric neutrino production


  The zenith angle distributions of atmospheric neutrinos are determined by the
possible presence of neutrino oscillations and the combination of three most
important contributions: (1) geomagnetic effects on the primary cosmic rays,
that suppress the primary flux in the Earth's magnetic equatorial region, (2)
the zenith angle dependence of the neutrino yields, due to the fact that
inclined showers produce more neutrinos, and (3) geometrical effects due to the
spherical shell geometry of the neutrino production volume. The last effect has
been recognized only recently and results in an important enhancement of the
flux of sub--GeV neutrinos for horizontal directions. In this work we discuss
the geometrical effect and its relevance in the interpretation of the
atmospheric neutrino data.

</DOC>
<DOC>
<DOCNO> 122727 </DOCNO>
Palomar 13's Last Stand


  We present a proper motion and CCD photometric study of stars in the distant
halo globular cluster Palomar 13. The absolute proper motion of Pal 13 with
respect to the background galaxies, derived from moderate scale photographic
plates separated by a 40-year baseline, is $(\mu_{\alpha cos \delta},
\mu_{\delta}) = (+2.30, +0.27) \pm (0.26, 0.25)$ milliarc-seconds per year. The
resultant total space velocity (315 km s$^{-1}$) implies that Pal 13 is in the
inner part of its orbit near perigalacticon. Orbital integration reveals the
cluster to possess an inclined, very eccentric, retrograde orbit. These data
confirm that Pal 13 is a paradigm "young halo" globular cluster.
  The derived proper motions for cluster stars are used to produce membership
probabilities and a cleaned CCD UBV catalogue for Pal 13. With this data set we
have made small revisions to Pal 13's distance, metallicity, position and light
profile. The membership of four previously reported RR Lyrae variables and a
proportionally large group of blue straggler stars are confirmed. As expected,
the blue stragglers are centrally concentrated.
  The small size of this cluster, combined with the shape of its light profile,
which shows a clear departure from a classical King function beyond the tidal
radius, suggests that Pal 13 is in the final throes of destruction. This could
explain the large blue straggler specific frequency, as destructive processes
would preferentially strip less massive stars.

</DOC>
<DOC>
<DOCNO> 174589 </DOCNO>
Polarization transfer in the $^{4}$He$(\vec{e},e' \vec{p}^{3}$H reaction


  Polarization transfer in the 4He(e,e'p)3H reaction at a Q^2 of 0.4 (GeV/c)^2
was measured at the Mainz Microtron MAMI. The ratio of the transverse to the
longitudinal polarization components of the ejected protons was compared with
the same ratio for elastic ep scattering. The results are consistent with a
recent fully relativistic calculation which includes a predicted medium
modification of the proton form factor based on a quark-meson coupling model.

</DOC>
<DOC>
<DOCNO> 150613 </DOCNO>
Casimir Effect in Background of Static Domain Wall


  In this paper we investigate the vacuum expectation values of energy-
momentum tensor for conformally coupled scalar field in the standard parallel
plate geometry with Dirichlet boundary conditions and on background of planar
domain wall case. First we calculate the vacuum expectation values of
energy-momentum tensor by using the mode sums, then we show that corresponding
properties can be obtained by using the conformal properties of the problem.
The vacuum expectation values of energy-momentum tensor contains two terms
which come from the boundary conditions and the the gravitational background.
In the Minkovskian limit our results agree with those obtained in [3].

</DOC>
<DOC>
<DOCNO> 13419 </DOCNO>
Electron Spin Flip Relaxation by One Magnon Processes: Application to


  The "s-f model", also known as the ferromagnetic Kondo lattice, contains a
description of band electrons coupled to localized spins which is an
appropriate description of the magnetic part of the low-energy physics of Gd
metal. Here the model is used to estimate the lifetime broadening of the
minority spin component of the surface electron band in ferromagnetic
gadolinium metal at temperatures below the Curie temperature. The low
temperature result 0.10 eV agrees nicely with a measurement by Fedorov et al.

</DOC>
<DOC>
<DOCNO> 100938 </DOCNO>
Monopole supersymmetries and the Biedenharn operator


  The hidden supersymmetry of the monopole found by De Jonghe et al. is
generalized to a spin $\2$ particle in the combined field of a Dirac monopole
plus a $\lambda^2/r^2$ potential [considered before by D'Hoker and Vinet], and
related to the operator introduced by Biedenharn a long time ago in solving the
Dirac-Coulomb problem. Explicit solutions are obtained by diagonalizing the
Biedenharn operator

</DOC>
<DOC>
<DOCNO> 170527 </DOCNO>
The Dirac algebra and its physical interpretation


  A version of the Dirac equation is derived from first principles using a
combination of quaternions and multivariate 4-vectors. The nilpotent form of
the operators used allows us to derive explicit expressions for the
wavefunctions of free fermions, vector bosons, scalar bosons; Bose-Einstein
condensates, and baryons;annihilation, creation and vacuum operators; the
quantum field integrals; and C, P and T transformations; and to suggest new
insights into the meaning of supersymmetry and renormalization.

</DOC>
<DOC>
<DOCNO> 40170 </DOCNO>
Search for Electroweak Production of Single Top Quarks in ppbar


  We present a search for electroweak production of single top quarks in the
electron+jets and muon+jets decay channels. The measurements use ~90 pb^-1 of
data from Run 1 of the Fermilab Tevatron collider, collected at 1.8 TeV with
the DZero detector between 1992 and 1995. We use events that include a tagging
muon, implying the presence of a b jet, to set an upper limit at the 95%
confidence level on the cross section for the s-channel process ppbar->tb+X of
39 pb. The upper limit for the t-channel process ppbar->tqb+X is 58 pb.

</DOC>
<DOC>
<DOCNO> 83467 </DOCNO>
When Can You Fold a Map?


  We explore the following problem: given a collection of creases on a piece of
paper, each assigned a folding direction of mountain or valley, is there a flat
folding by a sequence of simple folds? There are several models of simple
folds; the simplest one-layer simple fold rotates a portion of paper about a
crease in the paper by +-180 degrees. We first consider the analogous questions
in one dimension lower -- bending a segment into a flat object -- which lead to
interesting problems on strings. We develop efficient algorithms for the
recognition of simply foldable 1-D crease patterns, and reconstruction of a
sequence of simple folds. Indeed, we prove that a 1-D crease pattern is
flat-foldable by any means precisely if it is by a sequence of one-layer simple
folds.
  Next we explore simple foldability in two dimensions, and find a surprising
contrast: ``map'' folding and variants are polynomial, but slight
generalizations are NP-complete. Specifically, we develop a linear-time
algorithm for deciding foldability of an orthogonal crease pattern on a
rectangular piece of paper, and prove that it is (weakly) NP-complete to decide
foldability of (1) an orthogonal crease pattern on a orthogonal piece of paper,
(2) a crease pattern of axis-parallel and diagonal (45-degree) creases on a
square piece of paper, and (3) crease patterns without a mountain/valley
assignment.

</DOC>
<DOC>
<DOCNO> 99382 </DOCNO>
An Analysis on the Shape Equation for Biconcave Axisymmetric Vesicles


  We study the conditions on the physical parameters in the Helfrich bending
energy of lipid bilayer vesicles. Among embedded surfaces with a biconcave
axisymmetric shape, the variation equation is analyzed in detail. This leads to
simple conditions which guarantee the solution the information about the
geometry.

</DOC>
<DOC>
<DOCNO> 12301 </DOCNO>
Emergence of Fermi-Dirac Thermalization in the Quantum Computer Core


  We model an isolated quantum computer as a two-dimensional lattice of qubits
(spin halves) with fluctuations in individual qubit energies and residual
short-range inter-qubit couplings. In the limit when fluctuations and couplings
are small compared to the one-qubit energy spacing, the spectrum has a band
structure and we study the quantum computer core (central band) with the
highest density of states. Above a critical inter-qubit coupling strength,
quantum chaos sets in, leading to quantum ergodicity of eigenstates in an
isolated quantum computer. The onset of chaos results in the interaction
induced dynamical thermalization and the occupation numbers well described by
the Fermi-Dirac distribution. This thermalization destroys the noninteracting
qubit structure and sets serious requirements for the quantum computer
operability.

</DOC>
<DOC>
<DOCNO> 170443 </DOCNO>
Understanding Spin: the field theory of magnetic interactions


  Spin is commonly thought to reflect the true quantum nature of microphysics.
We show that spin is related to intrinsic and field-like properties of single
particles. These properties change continuously in external magnetic fields.
Interactions of massive particles with homogeneous and inhomogeneous fields
result in two discrete particle states, symmetric to the original one. We
analyze the difficulties in quantum mechanics to give a precise spacetime
account of the experiments and find that they arise from unsuitable analogies
for spin. In particular from the analogy of an angular momentum. Several
experiments are suggested to check the model against the standard model in
quantum mechanics.

</DOC>
<DOC>
<DOCNO> 11209 </DOCNO>
Some Recent Issues in Quantum Magnetism


  Summary of Quantum Magnetism Conference, Institute for Theoretical Physics,
University of California, Santa Barbara, California, August 16-20, 1999.

</DOC>
<DOC>
<DOCNO> 152267 </DOCNO>
Quantum Clifford Hopf Gebra for Quantum Field Theory


  We give arguments for the necessity to employ Quantum Clifford Hopf Gebras in
quantum field theory. The role of the antipode is examined, Feynman diagrams
are re-interpreted as tangles of graphical calculus. Regularization due to the
design of convolution Hopf gebras is given as a program for further research.

</DOC>
<DOC>
<DOCNO> 118776 </DOCNO>
The Ratio of Total to Selective Extinction Toward Baade's Window


  We measure the ratio of total to selective extinction, R_{VI}=A_V/E(V-I),
toward Baade's Window by comparing the VIK colors of 132 Baade's Window G and K
giants from Tiede, Frogel, & Terndrup with the solar-neighborhood (V-I),(V-K)
relation from Bessell & Brett. We find R_{VI}=2.283 +/- 0.016, and show that
our measurement has no significant dependence on stellar type from G0 to K4.
Adjusting the Paczynski et al. determination of the centroid of the dereddened
Baade's Window clump for this revised value of $R_{VI}$, we find I_{0,RC}=14.43
and (V-I)_{0,RC}=1.058. This implies a distance to the Baade's Window clump of
d_{BW} = 8.63 +/- 0.16 kpc, where the error bar takes account of statistical
but not systematic uncertainties.

</DOC>
<DOC>
<DOCNO> 100993 </DOCNO>
A local hidden variable theory for the GHZ experiment


  A recent analysis by de Barros and Suppes of experimentally realizable GHZ
correlations supports the conclusion that these correlations cannot be
explained by introducing local hidden variables. We show, nevertheless, that
their analysis does not exclude local hidden variable models in which the
inefficiency in the experiment is an effect not only of random errors in the
analyzer + detector equipment, but is also the manifestation of a pre-set,
hidden property of the particles ("prism models"). Indeed, we present an
explicit prism model for the GHZ scenario; that is, a local hidden variable
model entirely compatible with recent GHZ experiments.

</DOC>
<DOC>
<DOCNO> 120435 </DOCNO>
COBE- and Cluster-Normalized CDM Simulations


  We introduce a set of four new publicly available N-body simulations, the
most recent additions to the Texas P^3M Database. Our models probe the less
studied parameter space region of moderate volume (100/h Mpc box) combined with
fine mass resolution (~10^12 M_Sol, roughly comparable to a L_* galaxy), making
these simulations especially suitable for study of major large-scale structure
features such as voids, and for comparison with the largest three-dimensional
redshift surveys currently available. Our cosmological models (LCDM, TOCDM,
OCDM, TCDM) are all COBE-normalized, and when possible (LCDM and TOCDM) also
cluster-normalized, based on the X-ray cluster M--T relation. The COBE- and
cluster-normalized LCDM model reiterates the attractiveness of this currently
favored model which does not require the introduction of tilt in order to fit
the constraints imposed by observations of other cosmological parameters.

</DOC>
<DOC>
<DOCNO> 102327 </DOCNO>
Differentiable Cohomology of Gauge Groups


  We give a definition of differentiable cohomology of a Lie group G (possibly
infinite-dimensional) with coefficients in any abelian Lie group. This
differentiable cohomology maps both to the cohomology of the group made
discrete and to Lie algebra cohomology. We show that the secondary
characteristic classes of Beilinson lead to differentiable cohomology classes
with coefficients in C*. These may be viewed as an enrichment of the
Chern-Simons differential forms.
  By transgression, classes in differentiable cohomology of a Lie group G lead
to differentiable cohomology classes for gauge groups Map(M,G). These classes
generalize the central extensions of loop groups. We also discuss holomorphic
cohomology of complex Lie groups as the natural place to construct secondary
classes.
  We present several conjectures relating the above cohomology classes to the
differential forms of Bott-Shulman-Stasheff.

</DOC>
<DOC>
<DOCNO> 11716 </DOCNO>
Entropy concepts and DNA investigations


  Topological and metric entropies of the DNA sequences from different
organisms were calculated. Obtained results were compared each other and with
ones of corresponding artificial sequences. For all envisaged DNA sequences
there is a maximum of heterogeneity. It falls in the block length interval
[5,7].
 Maximum distinction between natural and artificial sequences is shifted on 1-3
position from the maximum of heterogeneity to the right as for metric as for
topological entropy. This point on the specificity of real DNA sequences in the
interval.

</DOC>
<DOC>
<DOCNO> 101024 </DOCNO>
The moduli space of N=1 superspheres with tubes and the sewing operation


  Within the framework of complex supergeometry and motivated by
two-dimensional genus-zero holomorphic N=1 superconformal field theory, we
define the moduli space of N=1 genus-zero super-Riemann surfaces with oriented
and ordered half-infinite tubes, modulo superconformal equivalence. We define a
sewing operation on this moduli space which gives rise to the sewing equation
and normalization and boundary conditions. To solve this equation, we develop a
formal theory of infinitesimal N=1 superconformal transformations based on a
representation of the N=1 Neveu-Schwarz algebra in terms of superderivations.
We solve a formal version of the sewing equation by proving an identity for
certain exponentials of superderivations involving infinitely many formal
variables. We use these formal results to give a reformulation of the moduli
space, a more detailed description of the sewing operation, and an explicit
formula for obtaining a canonical supersphere with tubes from the sewing
together of two canonical superspheres with tubes. We give some specific
examples of sewings, two of which give geometric analogues of associativity for
an N=1 Neveu-Schwarz vertex operator superalgebra. We study a certain linear
functional in the supermeromorphic tangent space at the identity of the moduli
space of superspheres with 1+1 tubes (one outgoing tube and one incoming tube)
which is associated to the N=1 Neveu-Schwarz element in an N=1 Neveu-Schwarz
vertex operator superalgebra. We prove the analyticity and convergence of the
infinite series arising from the sewing operation. Finally, we define a bracket
on the supermeromorphic tangent space at the identity of the moduli space of
superspheres with 1+1 tubes and show that this gives a representation of the
N=1 Neveu-Schwarz algebra with central charge zero.

</DOC>
<DOC>
<DOCNO> 121436 </DOCNO>
The GZK Feature in our Neighborhood of the Universe


  We calculate numerically the spectrum of ultra-high energy cosmic rays on
Earth assuming that their sources are distributed in space like the observed
galaxies. We use the CfA2 and the PSCz galaxy redshift surveys to model the
local galaxy distribution, properly taking into account the galaxy selection
functions for each survey. When the survey selection effects are included, we
find that the local overdensity is only a factor of two, an order of magnitude
less than used in some earlier studies. An overdensity of two is not enough to
bridge the gap between the predicted number of events above $10^{20}$ eV and
the measured flux at these highest energies. This conclusion is particularly
strong for soft injection spectra ($\propto E^{-3}$) where the observed number
of events is 6 $\sigma$ higher than the expected one. However, if the injection
spectrum is hard ($\propto E^{-2}$), the small local overdensity helps bring
the present data within 2$\sigma$ of the low number of events predicted above
$10^{20}$ eV. In this case, the Greisen-Zatzepin-Kuzmin cutoff is not a {\it
cutoff} but rather a {\it feature} in the cosmic ray spectrum.

</DOC>
<DOC>
<DOCNO> 120324 </DOCNO>
Modeling the X-ray - UV Correlations in NGC 3516


  We test the "reprocessing paradigm" of the optical -- UV AGN variability by
detailed modeling of the correlated X-ray -- optical (3590 and 5510 Angstrem)
variability of the recent multiwavelength campaign of NGC 3516. We produce
model optical light curves by convolving the observed X-ray flux with the
response function of an infinite, thin accretion disk, illuminated by a
point-like X-ray source at a given height above the compact object (the
lamp-post model) and compare their properties to those observed. Special
attention is given to the correct computation of the X-ray albedo of the disk.
We further compute the X-ray reflection response at two energies (E = 1 and 20
keV) and argue for the possibility of hard lags in their cross spectra. We also
compute the continuum Optical -- UV and the X-ray reflection spectra as well as
the Fe K-alpha fluorescent line profiles which we also compare to observations.
Despite the large (~50 percent) amplitude excursions of the X-ray flux, the
model optical light curves exhibit variability amplitudes of 3 -- 4 percent,
not unlike those observed. However, the model CCF between the X-ray and the
model optical variations show clear lags of 0.1 and 0.25 days for black hole
masses M = 10^7 and 10^8 Solar masses, respectively, not apparent in the data.
The synchrony of X-ray - optical variations points toward the BH mass < 10^7
Solar masses, whereas the X-ray spectra prefer BH mass > 10^8. Our conclusion
is that the combination of the observed optical/UV/X-ray spectral and timing
observations are inconsistent with the lamp-post model geometry for NGC 3516.

</DOC>
<DOC>
<DOCNO> 120292 </DOCNO>
Magnetic deformation of the white dwarf surface structure


  The influence of strong, large-scale magnetic fields on the structure and
temperature distribution in white dwarf atmospheres is investigated. Magnetic
fields may provide an additional component of pressure support, thus possibly
inflating the atmosphere compared to the non-magnetic case. Since the magnetic
forces are not isotropic, atmospheric properties may significantly deviate from
spherical symmetry. In this paper the magnetohydrostatic equilibrium is
calculated numerically in the radial direction for either for small deviations
from different assumptions for the poloidal current distribution. We generally
find indication that the scale height of the magnetic white dwarf atmosphere
enlarges with magnetic field strength and/or poloidal current strength. This is
in qualitative agreement with recent spectropolarimetric observations of
Grw$+10\degr8247$. Quantitatively, we find for e.g. a mean surface poloidal
field strength of 100 MG and a toroidal field strength of 2-10 MG an increase
of scale height by a factor of 10. This is indicating that already a small
deviation from the initial force-free dipolar magnetic field may lead to
observable effects. We further propose the method of finite elements for the
solution of the two-dimensional magnetohydrostatic equilibrium including
radiation transport in the diffusive approximation. We present and discuss
preliminary solutions, again indicating on an expansion of the magnetized
atmosphere.

</DOC>
<DOC>
<DOCNO> 8989 </DOCNO>
Inhomogeneity-Induced Superconductivity?


  A t-J-like model for inhomogeneous superconductivity of cuprate oxides is
presented, in which local anisotropic magnetic terms are essential. We show
that this model predicts pairing, consistent with experiments, and argue how
the macroscopic phase-coherent state gradually grows upon lowering of the
temperature. We show that appropriate inhomogeneities are essential in order to
have significant pair binding in the thermodynamic limit. Particularly, {\it
local} breaking of SU(2) spin symmetry is an efficient mechanism for inducing
pairing of two holes, as well as explaining the magnetic scattering properties.
We also discuss the connection of the resulting inhomogeneity-induced
superconductivity to recent experimental evidence for a linear relation between
magnetic incommensurability and the superconducting transition temperature, as
a function of doping.

</DOC>
<DOC>
<DOCNO> 8495 </DOCNO>
Vesicle propulsion in haptotaxis : a local model


  We study theoretically vesicle locomotion due to haptotaxis.
  Haptotaxis is referred to motion induced by an adhesion gradient on a
substrate. The problem is solved within a local approximation where a
Rayleigh-type dissipation is adopted. The dynamical model is akin to the Rousse
model for polymers. A powerful gauge-field invariant formulation is used to
solve a dynamical model which includes a kind of dissipation due to bond
breaking/restoring with the substrate. For a stationary situation where the
vesicle acquires a constant drift velocity, we formulate the propulsion problem
in terms of a nonlinear eigenvalue (the a priori unknown drift velocity) one of
Barenblat-Zeldovitch type. A counting argument shows that the velocity belongs
to a discrete set. For a relatively tense vesicle, we provide an analytical
expression for the drift velocity as a function of relevant parameters. We find
good agreement with the full numerical solution. Despite the oversimplification
of the model it allows the identification of a relevant quantity, namely the
adhesion length, which turns out to be crucial also in the nonlocal model in
the presence of hydrodynamics, a situation on which we have recently reported
[I. Cantat, and C. Misbah, Phys. Rev. Lett. {\bf 83}, 235 (1999)] and which
constitutes the subject of a forthcoming extensive study.

</DOC>
<DOC>
<DOCNO> 71461 </DOCNO>
Density perturbations arising from multiple field slow-roll inflation


  In this paper we analyze scalar gravitational perturbations on a
Robertson-Walker background in the presence of multiple scalar fields that take
values on a (geometrically non-trivial) field manifold during slow-roll
inflation. For this purpose modified and generalized slow-roll functions are
introduced and their properties examined. These functions make it possible to
estimate to what extent the gravitational potential decouples from the scalar
field perturbations. The correlation function of the gravitational potential is
calculated in an arbitrary state. We argue that using the vacuum state seems a
reasonable assumption for those perturbations that can be observed in the CMBR.
Various aspects are illustrated by examples with multiple scalar fields that
take values on flat and curved manifolds.

</DOC>
<DOC>
<DOCNO> 72065 </DOCNO>
Strong hadronic decays in QCD_2


  Strong hadronic decays are discussed in the 't Hooft model for the
two-dimensional QCD in the limit of infinite number of colours. Adler
selfconsistency condition is derived for decays with pions in the final state
and the corresponding amplitude is demonstrated to vanish identically in the
chiral limit.

</DOC>
<DOC>
<DOCNO> 152403 </DOCNO>
Gauge Symmetry Breakdown due to Dyanamical versus Elementary Higgs


  We study in details on how gauge bosons can acquire mass when the chiral
symmetry dynamically breaks down for massless gauge theory without scalars.
Introducing dynamical scalar fields into the original gauge theory, we show
that when the chiral symmetry breaks down, the theory gives gauge boson masses
different from what would be obatained if an elemetary Higgs is included. We
clarify the reason and propose one method how to calculate gauge boson masses
in the case of dynamical gauge symmtry breakdown. We explain the method by
using an example in which SU(5) massless gauge theory breaks down to SU(4) with
massless fermions in appropriate representations.

</DOC>
<DOC>
<DOCNO> 9548 </DOCNO>
The fully frustrated XY model with next nearest neighbor interaction


  We introduce a fully frustrated XY model with nearest neighbor (nn) and next
nearest neighbor (nnn) couplings which can be realized in Josephson junction
arrays. We study the phase diagram for $0\leq x \leq 1$ ($x$ is the ratio
between nnn and nn couplings). When $x < 1/\sqrt{2}$ an Ising and a
Berezinskii-Kosterlitz-Thouless transitions are present. Both critical
temperatures decrease with increasing $x$. For $x > 1/\sqrt{2}$ the array
undergoes a sequence of two transitions. On raising the temperature first the
two sublattices decouple from each other and then, at higher temperatures, each
sublattice becomes disorderd.

</DOC>
<DOC>
<DOCNO> 11127 </DOCNO>
Nonadiabatic theory of the superconducting state


  Fermi energies in fullerene compounds and cuprates are extremely small as
consequence of the small number of charge carriers and are comparable to the
phonon frequency scale. In this situation the conventional Migdal-Eliashberg
theory does not hold anymore and nonadiabatic effects need to be taken into
account. In previous studies, a generalization of Eliashberg theory in the
nonadiabatic regime has been proposed to calculate normal state properties and
the onset temperature $T_c$ of the superconductive phase. Here we extend the
nonadiabatic theory below $T_c$ where the opening of the superconducting order
parameter affects the nonadiabatic correction. The superconducting gap $\Delta$
is calculated in a self-consistent way. We find that large values of the ratio
$2 \Delta/T_c$ are obtained in the nonadiabatic theory by smaller
electron-phonon coupling $\lambda$ than in Migdal-Eliashberg theory. This
agrees with the picture that strong-coupling phenomenology can be achieved in
nonadiabatic theory by ``reasonable'' values of $\lambda$. We apply our
analysis to the case of the fullerene compounds.

</DOC>
<DOC>
<DOCNO> 68284 </DOCNO>
Impact of Physical Principles at Very High Energy Scales on the


  We survey a variety of proposals for new physics at high scales that serve to
relate the multitude of soft supersymmetry breaking parameters of the MSSM. We
focus on models where the new physics results in non-universal soft parameters,
in sharp contrast with the usually assumed mSUGRA framework. These include {\it
i}) SU(5) and SO(10) grand unified (GUT) models, {\it ii}) the MSSM plus a
right-handed neutrino, {\it iii}) models with effective supersymmetry, {\it
iv}) models with anomaly-mediated SUSY breaking and gaugino mediated SUSY
breaking, {\it v}) models with non-universal soft terms due to string dynamics,
and {\it vi}) models based on $M$-theory. We outline the physics behind these
models, point out some distinctive features of the weak scale sparticle
spectrum, and allude to implications for collider experiments. To facilitate
future studies, for each of these scenarios, we describe how collider events
can be generated using the program ISAJET. Our hope is that detailed studies of
a variety of alternatives will help point to the physics underlying SUSY
breaking and how this is mediated to the observable sector, once sparticles are
discovered and their properties measured.

</DOC>
<DOC>
<DOCNO> 7920 </DOCNO>
Two-dimensional charged electron-hole complexes in magnetic fields:


  Eigenstates of 2D charged electron-hole complexes in magnetic fields are
considered. The operator formalism that allows one to partially separate the
center-of-mass motion from internal degrees of freedom is presented. The scheme
using magnetic translations is developed for calculating in strong magnetic
fields the eigenspectra of negatively charged excitons X^-, a bound state of
two electrons and one hole.

</DOC>
<DOC>
<DOCNO> 116506 </DOCNO>
The Physical Origin of Intrinsic Bends in Double Helical DNA


  The macroscopic curvature induced in the double helical B-DNA by regularly
repeated adenine tracts (A-tracts) is a long known, but still unexplained
phenomenon. This effect plays a key role in DNA studies because it is unique in
the amount and the variety of the available experimental information and,
therefore, is likely to serve as a gate to the unknown general mechanisms of
recognition and regulation of genome sequences. We report the results of
molecular dynamics simulations of a 25-mer B-DNA fragment with a sequence
including three A-tract phased with the helical screw. It represents the first
model system where properly directed static curvature emerges spontaneously in
conditions excluding any initial bias except the base pair sequence. The effect
has been reproduced in three independent MD trajectories of 10-20 ns with
important qualitative details suggesting that the final bent state is a strong
attractor of trajectories form a broad domain of the conformational space. The
ensemble of curved conformations, however, reveals significant microscopic
heterogeneity in contradiction to all existing theoretical models of bending.
Analysis of these unexpected observations leads to a new, significantly
different hypothesis of the possible mechanism of intrinsic bends in the double
helical DNA.

</DOC>
<DOC>
<DOCNO> 11034 </DOCNO>
The Spallation Neutron Source: A Powerful Tool for Materials Research


  The wavelengths and energies of thermal and cold neutrons are ideally matched
to the length and energy scales in the materials that underpin technologies of
the present and future: ranging from semiconductors to magnetic devices,
composites to biomaterials and polymers. The Spallation Neutron Source (SNS)
will use an accelerator to produce the most intense beams of neutrons in the
world when it is complete at the end of 2005. The project is being built by a
collaboration of six U.S. Department of Energy laboratories. It will serve a
diverse community of users drawn from academia, industry, and government labs
with interests in condensed matter physics, chemistry, engineering materials,
biology, and beyond.

</DOC>
<DOC>
<DOCNO> 101759 </DOCNO>
Asymptotic Electromagnetic Fields in Models of Quantum-Mechanical Matter


  In models of (non-relativistic and pseudo-relativistic) electrons interacting
with static nuclei and with the (ultraviolet-cutoff) quantized radiation field,
the existence of asymptotic electromagnetic fields is established. Our results
yield some mathematically rigorous understanding of Rayleigh scattering and of
the phenomenon of relaxation of isolated atoms to their ground states. Our
proofs are based on propagation estimates for electrons inspired by similar
estimates known from $N$-body scattering theory.

</DOC>
<DOC>
<DOCNO> 71793 </DOCNO>
The Drell-Hearn Sum Rule at Order Alpha**3


  The Drell-Hearn-Gerasimov-Iddings (DHGI) sum rule for electrons is evaluated
at order $\alpha^3$ and shown to agree with the Schwinger contribution to the
anomalous magnetic moment.

</DOC>
<DOC>
<DOCNO> 84158 </DOCNO>
General Ether Theory


  The paper is an introduction into General Ether Theory (GET). We start with
few assumptions about an universal ``ether'' in a Newtonian space-time which
fulfils
 \partial_t \rho + \partial_i (\rho v^i) = 0
 \partial_t (\rho v^j) + \partial_i(\rho v^i v^j + p^{ij}) = 0
  For an ``effective metric'' $g_{\mu\nu}$ we derive a Lagrangian where the
Einstein equivalence principle is fulfilled:
  L=L_{GR}-(8\pi G)^{-1}(\Upsilon g^{00}-\Xi(g^{11}+g^{22}+g^{33}))\sqrt{-g}
  We consider predictions (stable frozen stars instead of black holes, big
bounce instead of big bang singularity, a dark matter term), quantization
(regularization by an atomic ether, superposition of gravitational fields),
related methodological questions (covariance, EPR criterion, Bohmian
mechanics).

</DOC>
<DOC>
<DOCNO> 120072 </DOCNO>
Joule Heating in Neutron Stars under Strong Gravitation


  Considering Joule heating caused by the dissipation of the magnetic field in
the neutron star crust to be an efficient mechanism in maintaining a relatively
high surface temperature in very old neutron stars, the role of general
relativity is investigated. It is found that, although the effect of space-time
curvature produced by the intense gravitational field of the star slows down
the decay rate of the magnetic field, modification of the initial magnetic
field configuration and the initial field strength by the space-time curvature
results in increasing the rate of Joule heating. Hence the space-time curvature
supports Joule heating in maintaining a relatively high surface temperature
which is consistent with the bservational detection.

</DOC>
<DOC>
<DOCNO> 101972 </DOCNO>
Linguistic Paradoxes and Tautologies


  Classes of linguistic paradoxes and linguistic tautologies are introduced
with examples and explanations. They are part of the author's work on the
Paradoxist Philosophy based on mathematical logic.
  The general cases exposed below are modeled on the English language structure
in a rigid way. In order to find nice particular examples of such paradoxes and
tautologies one grammatically adjusts the sentences.

</DOC>
<DOC>
<DOCNO> 85377 </DOCNO>
Supersymmetry of the extreme rotating toroidal black hole


  We study the supersymmetry of the charged rotating toroidal black hole
solutions found by Lemos and Zanchin, and show that the only configurations
that are supersymmetric are: (i) the non-rotating electrically charged naked
singularities already studied by Caldarelli and Klemm, and (ii) an extreme
rotating toroidal black hole with zero magnetic and electric charges. For this
latter case, the extreme uncharged black hole, we calculate the Killing spinors
and show that the configuration preserves the same supersymmetries as the
background spacetime.

</DOC>
<DOC>
<DOCNO> 67970 </DOCNO>
On the spontaneous breaking of Lorentz invariance


  We show that estimates of the Lorentz symmetry violation extracted from
ultra-high energy cosmic rays beyond the GZK cut-off set bounds on the
parameters of a Lorentz-violating extension of the Standard Model. Moreover, we
argue that correlated measurements of the difference in the arrival time of
gamma-ray photons and neutrinos emitted from Active Galactic Nuclei or
Gamma-Ray Bursts may provide a signature for a possible violation of the
Lorentz symmetry. We find that this time delay is energy independent, but that
it has a dependence on the chirality of the particles involved.

</DOC>
<DOC>
<DOCNO> 72285 </DOCNO>
Unitarity constraints on scalar parameters of the Standard and Two Higgs


  Unitarity constraints on the scalar parameters both for the Standard Model
and the general Two Higgs Doublet Model (THDM) are examined. In the case of the
THDM with an exact discrete symmetry transformation, we show that the mass of
the lightest CP-even Higgs boson ($M_h$) and $\tan\beta$ are strongly
correlated and consequently a strong lower bound can be put on $M_h$ for large
$\tan\beta$. It is also shown that the inclusion of the discrete symmetry
breaking term relaxes the aforementioned correlation.

</DOC>
<DOC>
<DOCNO> 121524 </DOCNO>
Spin induced galaxy alignments and their implications for weak lensing


  Large scale correlations in the orientations of galaxies can result from
alignments in their angular momentum vectors. These alignments arise from the
tidal torques exerted on neighboring proto-galaxies by the smoothly varying
shear field. We compute the predicted amplitude of such ellipticity
correlations using the Zel'dovich approximation for a realistic distribution of
galaxy shapes. Weak gravitational lensing can also induce ellipticity
correlations since the images of neighboring galaxies will be distorted
coherently. On comparing these two effects that induce shape correlations, we
find that for current weak lensing surveys with a median redshift of z_m = 1,
the intrinsic signal is of order 1 - 10 percent of the measured signal.
However, for shallower surveys with z_m < 0.3, the intrinsic correlations
dominate over the lensing signal. The distortions induced by lensing are
curl-free, whereas those resulting from intrinsic alignments are not. This
difference can be used to disentangle these two sources of ellipticity
correlations.

</DOC>
<DOC>
<DOCNO> 120051 </DOCNO>
Constraints on the physical properties of the damped Ly-alpha system of


  We present the detection of CII and CII* absorption in the z = 3.0543 damped
Ly-alpha system toward Q0000-2619. The derived population ratio implies a fine
structure excitation temperature between 19.6 and 21.6 K. The upper value sets
a strict upper limit on the CMB temperature at this redshift, which is
consistent with the predicted value of 11.05 K from standard cosmology. Under
the assumptions of an ionization degree ranging from 0 to 10%, a gas kinetic
temperature between 100 and 10000 K and a UV field with a Milky Way spectrum,
the density of the absorber is constrained to be between 0.7 and 40 cm^-3 and
the H-ionizing flux between 1 and 80 times the intensity of the Galactic UV
field. If the damped Ly-alpha system is assumed to be homogeneous, the
implication is that its size in the direction of the line of sight must be
between 1 and 100 pc.

</DOC>
<DOC>
<DOCNO> 80900 </DOCNO>
Scalar and Tensor Glueballs on Asymmetric Coarse Lattices


  Scalar and tensor glueball spectrum is studied using an improved gluonic
action on asymmetric lattices in the pure SU(3) gauge theory. The smallest
spatial lattice spacing is about 0.08fm which makes the extrapolation to the
continuum limit more reliable. In particular, attention is paid to the scalar
glueball mass which is known to have problems in the extrapolation. Converting
our lattice results to physical units using the scale set by the static quark
potential, we obtain the following results for the glueball masses:
$M_G(0^{++})=1730(90)MeV$ for the scalar glueball mass and
$M_G(2^{++})=2400(95)MeV$ for the tensor glueball.

</DOC>
<DOC>
<DOCNO> 69448 </DOCNO>
Effective String Theory of Vortices and Regge Trajectories


  Starting from a field theory containing classical vortex solutions, we obtain
an effective string theory of these vortices as a path integral over the two
transverse degrees of freedom of the string. We carry out a semiclassical
expansion of this effective theory, and use it to obtain corrections to Regge
trajectories due to string fluctuations.

</DOC>
<DOC>
<DOCNO> 68981 </DOCNO>
Topics in Finite Temperature Field Theory


  We discuss a few selected topics in finite temperature field theory.

</DOC>
<DOC>
<DOCNO> 12941 </DOCNO>
Formation of two-dimensional weak localization in conducting


  We report the magnetotransport properties up to 7 T in the organic highly
conducting Langmuir-Blodgett(LB) films formed by a molecular association of the
electroactive donor molecule bis(ethylendioxy)tetrathiafulvalene (BEDO-TTF) and
stearic acid CH$_3$(CH$_2$)$_{16}$COOH. We show the logarithmic decrease of dc
conductivity and the negative transverse magnetoresistance at low temperature.
They are interpreted in the weak localization of two-dimensional (2D)
electronic system based on the homogeneous conducting layer with the molecular
size thickness of BEDO-TTF. The electronic length with phase memory is given at
the mesoscopic scale, which provides for the first time evidence of the 2D
coherent charge transport in the conducting LB films.

</DOC>
<DOC>
<DOCNO> 14074 </DOCNO>
Magnetotransport in lateral superlattices with small-angle impurity


  An analytical study of the low-field magnetoresistance of a two-dimensional
electron gas subject to a weak periodic modulation is presented. We assume
small-angle impurity scattering characteristic for high-mobility semiconductor
heterostructures. It is shown that the condition for existence of the strong
low-field magnetoresistance induced by so-called channeled orbits is
$\eta^{3/2}ql\gg 1$, where $\eta$ and $q$ are the strength and the wave vector
of the modulation, and $l$ is the transport mean free path. Under this
condition, the magnetoresistance scales as $\eta^{7/2}$.

</DOC>
<DOC>
<DOCNO> 8267 </DOCNO>
Critical behavior of thermopower and conductivity at the metal-insulator


  This letter reports thermopower and conductivity measurements through the
metal-insulator transition for 2-dimensional electron gases in high mobility
Si-MOSFET's. At low temperatures both thermopower and conductivity show
critical behavior as a function of electron density which is very similar to
that expected for an Anderson transition. In particular, when approaching the
critical density from the metallic side the diffusion thermopower appears to
diverge and the conductivity vanishes. On the insulating side the thermopower
shows an upturn with decreasing temperature.

</DOC>
<DOC>
<DOCNO> 152049 </DOCNO>
Renormalization Constant of the Color Gauge Field as a Probe of


  The mechanism of color confinement as a consequence of an unbroken
non-abelian gauge symmetry and asymptotic freedom is elucidated and compared
with that of other models based on an analogy with the type II superconductor.
It is demonstrated that a sufficient condition for color confinement is given
by $Z_3^{-1}=0$ where $Z_3$ denotes the renormalization constant of the color
gauge field. It is shown that this condition is actually satisfied in quantum
chromodynamics and that some of the characteristic features of other models
follow from it.

</DOC>
<DOC>
<DOCNO> 116989 </DOCNO>
RF Processing of X-band Accelerator Structures at the NLCTA


  During the initial phase of operation, the linacs of the Next Linear Collider
(NLC) will contain roughly 5000 X-Band accelerator structures that will
accelerate beams of electrons and positrons to 250 GeV. These structures will
nominally operate at an unloaded gradient of 72 MV/m. As part of the NLC R&D
program, several prototype structures have been built and operated at the Next
Linear Collider Test Accelerator (NLCTA) at SLAC. Here, the effect of high
gradient operation on the structure performance has been studied. Significant
progress was made during the past year after the NLCTA power sources were
upgraded to reliably produce the required NLC power levels and beyond. This
paper describes the structures, the processing methodology and the observed
effects of high gradient operation.

</DOC>
<DOC>
<DOCNO> 152046 </DOCNO>
Maximal gauged supergravity in three dimensions


  We construct maximally supersymmetric gauged N=16 supergravity in three
dimensions, thereby obtaining an entirely new class of AdS supergravities.
These models are not derivable from any known higher-dimensional theory,
indicating the existence of a new type of supergravity beyond D=11. They are
expected to be of special importance also for the conjectured AdS/CFT
correspondence. One of their noteworthy features is a nonabelian generalization
of the duality between scalar and vector fields in three dimensions. Among the
possible gauge groups, SO(8)xSO(8) is distinguished as the maximal compact
gauge group, but there are also more exotic possibilities such as F_4 x G_2.

</DOC>
<DOC>
<DOCNO> 152626 </DOCNO>
Counterterms in Supergravity


  We examine the ultraviolet behaviour of supergravity theories as a function
of dimension and number of supercharges. We do so by the computation of one and
two-loop physical on-shell four point amplitudes. For maximal supergravity, our
computations prove the non-renomalisability of supergravity for $D \geq 6$
(including the maximal D=11 case) and give strong evidence for the existance of
a five-loop counterterm in D=4. For type I supergravity our results indicate
similar patterns. e shall also explore a remarkable relationship between
gravity amplitudes and those of Yang-Mills theories. In many ways gravity
calculations discover features which relate to the equivalent Yang-Mills
features by a squaring proceedure.

</DOC>
<DOC>
<DOCNO> 100697 </DOCNO>
Counting Yang-Mills Dyons with Index Theorems


  We count the supersymmetric bound states of many distinct BPS monopoles in
N=4 Yang-Mills theories and in pure N=2 Yang-Mills theories. The novelty here
is that we work in generic Coulombic vacua where more than one adjoint Higgs
fields are turned on. The number of purely magnetic bound states is again found
to be consistent with the electromagnetic duality of the N=4 SU(n) theory, as
expected. We also count dyons of generic electric charges, which correspond to
1/4 BPS dyons in N=4 theories and 1/2 BPS dyons in N=2 theories. Surprisingly,
the degeneracy of dyons is typically much larger than would be accounted for by
a single supermultiplet of appropriate angular momentum, implying many
supermutiplets of the same charge and the same mass.

</DOC>
<DOC>
<DOCNO> 102460 </DOCNO>
Some local wellposedness results for nonlinear Schroedinger equations


  We prove some local (in time) wellposedness results for nonlinear
Schroedinger equations with rough data, that is, the initial value belongs to
some Sobolev space of negative index. The proof uses the Fourier restriction
norm method.

</DOC>
<DOC>
<DOCNO> 150737 </DOCNO>
Comments on Instantons on Noncommutative R^4


  We study U(1) and U(2) instanton solutions on noncommutative R^4 based on the
noncommutative version of ADHM equation proposed by Nekrasov and Schwarz. It is
shown that the anti-self-dual gauge fields on self-dual noncommutative R^4
correctly give integer instanton numbers for all cases we consider. We also
show that the completeness relation in the ADHM construction is generally
satisfied even for noncommutative spaces.

</DOC>
<DOC>
<DOCNO> 70496 </DOCNO>
Corrections to the Higgs Boson Masses and Mixings from Chargino, W and


  One loop contributions to the Higgs boson masses and mixings from the
chargino sector consisting of the chargino, the W, and the charged Higgs boson
($\chi^+-W-H^+$) exchanges and including the effects of large CP violating
phases are computed. It is found that the chargino sector makes a large
contribution to the mixings of the CP even and the CP odd Higgs sectors through
the induced one loop effects and may even dominate the mixing generated by the
stop and the sbottom sectors. Effects of the chargino sector contribution to
the Higgs boson masses are also computed. It is found that the sum of the
$\chi^+-W-H^+$ exchange contribution lowers the lightest Higgs boson mass and
worsens the fine tuning problem implied by the LEP data. Phenomenological
implications of these results are discussed.

</DOC>
<DOC>
<DOCNO> 178764 </DOCNO>
Dyson-Schwinger calculations of meson form factors


  The ladder-rainbow truncation of the set of Dyson-Schwinger equations is used
to study the pion and kaon electromagnetic form factors and the $\gamma^\star
\pi^0 \gamma$ transition form factor in impulse approximation. With model
parameters previously fixed by the pseudoscalar meson masses and decay
constants, the obtained form factors are in good agreement with the data.

</DOC>
<DOC>
<DOCNO> 11689 </DOCNO>
Depinning of an anisotropic interface in random media: The tilt effect


  We study the tilt dependence of the pinning-depinning transition for an
interface described by the anisotropic quenched Kardar-Parisi-Zhang equation in
2+1 dimensions, where the two signs of the nonlinear terms are different from
each other. When the substrate is tilted by m along the positive sign
direction, the critical force F_c(m) depends on m as F_c(m)-F_c(0) \sim
-|m|^{1.9(1)}. The interface velocity v near the critical force follows the
scaling form v \sim |f|^{\theta}\Psi_{\pm}(m^2 /|f|^{\theta+\phi}) with \theta
= 0.9(1) and \phi= 0.2(1), where f \equiv F-F_c(0) and F is the driving force.

</DOC>
<DOC>
<DOCNO> 13935 </DOCNO>
Thermodynamically Important Contacts in Folding of Model Proteins


  We introduce a quantity, the entropic susceptibility, that measures the
thermodynamic importance-for the folding transition-of the contacts between
amino acids in model proteins. Using this quantity, we find that only one
equilibrium run of a computer simulation of a model protein is sufficient to
select a subset of contacts that give rise to the peak in the specific heat
observed at the folding transition. To illustrate the method, we identify
thermodynamically important contacts in a model 46-mer. We show that only about
50% of all contacts present in the protein native state are responsible for the
sharp peak in the specific heat at the folding transition temperature, while
the remaining 50% of contacts do not affect the specific heat.

</DOC>
<DOC>
<DOCNO> 11868 </DOCNO>
Irreversibility resulting from contact with a heat bath caused by the


  When a small dynamical system that is initially in contact with a heat bath
is detached from this heat bath and then caused to undergo a quasi-static
adiabatic processes, the statistical distribution of the system's energy
differs from that of an equilibrium ensemble. Subsequent contact of the system
with another heat bath is inevitably irreversible, hence the entire process
cannot be reversed without a net energy transfer to the heat baths.

</DOC>
<DOC>
<DOCNO> 116604 </DOCNO>
Mechanical model for gravity


  Assuming the existence of a Multidirectional Homogeneous and Constant Shower
of Elementary Particles (MHCSEP) traveling at light speed in space, several
basic laws of physics are derived mainly by geometrical considerations. When
placing two bodies in space, obstruction of the MHCSEP creates an attractive
force among them that coincides, for two bodies, with Newton's law of gravity,
generating a mechanical explanation for gravity.

</DOC>
<DOC>
<DOCNO> 11510 </DOCNO>
Response: Spin-Singlet clusters in the ladder compound NaV2O5


  This response on a Comment on Reference 2 discusses the space group Fmm2
determination of the low temperature structure of NaV2O5. We show that while
conventional crystallography is consistent with 'zig-zag' charge ordering of
half of the ladders, recent spectroscopic measurements suggest that the
symmetry is lower than Fmm2. We suggest space group C2, consistent with full
'zig-zag' charge ordering of all the ladders.

</DOC>
<DOC>
<DOCNO> 8224 </DOCNO>
Advanced Lanczos diagonalization for models of quantum disordered


  An application of an effective numerical algorithm for solving eigenvalue
problems which arise in modelling electronic properties of quantum disordered
systems is considered. We study the electron states at the
localization-delocalization transition induced by a random potential in the
framework of the Anderson lattice model. The computation of the interior of the
spectrum and corresponding wavefunctions for very sparse, hermitian matrices of
sizes exceeding 10^6 x 10^6 is performed by the Lanczos-type method especially
modified for investigating statistical properties of energy levels and
eigenfunction amplitudes.

</DOC>
<DOC>
<DOCNO> 85098 </DOCNO>
3D Gravity, Point Particles and Liouville Theory


  This paper elaborates on the bulk/boundary relation between negative
cosmological constant 3D gravity and Liouville field theory (LFT). We develop
an interpretation of LFT non-normalizable states in terms of particles moving
in the bulk. This interpretation is suggested by the fact that ``heavy'' vertex
operators of LFT create conical singularities and thus should correspond to
point particles moving inside AdS. We confirm this expectation by comparing the
(semi-classical approximation to the) LFT two-point function with the
(appropriately regularized) gravity action evaluated on the corresponding
metric.

</DOC>
<DOC>
<DOCNO> 69272 </DOCNO>
On the Consistency of the Exact Renormalization Group Approach Applied


  We study a class of Wilsonian formulations of non-Abelian gauge theories in
algebraic non-covariant gauges where the Wilsonian infrared cutoff $\Lambda$ is
inserted as a mass term for the propagating fields. In this way the
Ward-Takahashi identities are preserved to all scales. Nevertheless
BRST-invariance in broken and the theory is gauge-dependent and unphysical at
$\Lambda\neq0$. Then we discuss the infrared limit $\Lambda\to0$. We show that
the singularities of the axial gauge choice are avoided in planar gauge and
light-cone gauge. In addition the issue of infrared divergences is addressed in
some explicit example. Finally the rectangular Wilson loop of size $2L\times
2T$ is evaluated at lowest order in perturbation theory and a non commutativity
between the limits $\Lambda\to0$ and $T\to\infty$ is pointed out.

</DOC>
<DOC>
<DOCNO> 13181 </DOCNO>
Spin relaxation in asymmetrical heterostructures


  Electron spin relaxation caused by the D'yakonov-Perel' mechanism is
investigated theoretically in asymmetrical A$_3$B$_5$ heterostructures. The
total spin relaxation anisotropy is demonstrated for a wide range of structure
parameters and temperatures. The spin relaxation rates dependences are derived
for GaAs-based heterojunction and triangular quantum well. The calculations
show a few orders of magnitude difference in spin relaxation times.

</DOC>
<DOC>
<DOCNO> 70176 </DOCNO>
Electroweak Precision Physics at e+ e- Colliders with RacoonWW


  We present precise predictions for the processes e+ e- -> WW -> 4f(gamma) at
LEP2 and future Linear-Collider (LC) energies obtained with the Monte Carlo
generator RacoonWW. The program RacoonWW includes the complete O(alpha)
electroweak radiative corrections to e+ e- -> WW -> 4f in the double-pole
approximation (DPA). While the virtual corrections are treated in DPA, the
calculation of the bremsstrahlung corrections is based on the full lowest-order
matrix elements to the processes e+ e- -> 4f+gamma. This asymmetric treatment
of virtual and real photons requires a careful matching of the arising infrared
and collinear singularities. We also take into account higher-order
initial-state photon radiation via the structure-function method. Here, we
briefly describe the RacoonWW approach, give numerical results for the total
W-pair production cross sections, confront them with LEP2 data, and study the
impact of the radiative corrections on angular and W-invariant-mass
distributions at LEP2 and LC energies.

</DOC>
<DOC>
<DOCNO> 10402 </DOCNO>
The flux phase problem on the ring


  We give a simple proof to derive the optimal flux which minimizes the ground
state energy in one dimensional Hubbard model, provided the number of particles
is even.

</DOC>
<DOC>
<DOCNO> 170808 </DOCNO>
Classification of transformations of probabilities for preparation


  We provide frequency probabilistic analysis of perturbations of physical
systems by preparation procedures. We obtained the classification of possible
probabilistic transformations connecting input and output probabilities that
can appear in physical experiments. We found that so called quantum
probabilistic rule is just one of possible rules. Besides the well known
trigonometric transformation (for example, for the polarization of light),
there exist the hyperbolic transformation of probabilities. In fact,
`hyperbolic polarization' have laready been observed in experiments with
elementary particles. However, it was not interpreted in such a way. The
situation is more complex with the hyperbolic interference of alternatives.

</DOC>
<DOC>
<DOCNO> 99384 </DOCNO>
Remarks on the existence of Cartier divisors


  Given an invertible sheaf, does it come from a Cartier divisor? This might
fail in presence of embedded components. I give some examples and characterize
those invertible sheaves that allow a Cartier divisor.

</DOC>
<DOC>
<DOCNO> 12385 </DOCNO>
Anisotropy of flux-flow resistivity in UPt3


  The ac prenetration depth, \lambda_ac(T,H,f), has been measured in
superconducting UPt3 single crystals for H\parallel c and H\perp c in the range
f=0.01-1MHz and T=0.1-0.4 K. The contributions from bulk pinning and surface
pinning have been separated out to yield the flux-flow resistivity \rho_f(H).
With H\perp c, rho_f displays magneto-resistance at low field which agrees with
previous dc measurements and the characteristic scaling law of clean crystals
with anisotropic gap. When H\parallel c, the low-field \rho_f is three times
larger. We interpret this property as evidence for flux line with
unconventional core structure.

</DOC>
<DOC>
<DOCNO> 80949 </DOCNO>
Testing perturbative results with non-perturbative methods for the


  We present non-perturbative methods to calculate accurately the renormalized
quantities for Dyson's Hierarchical Model. We apply this method and calculate
the critical exponent gamma with 12 and 4 significant digits in the high and
low temperature phases, respectively. We report accurate values for universal
ratios of amplitudes and preliminary results concerning the comparison with
perturbative results.

</DOC>
<DOC>
<DOCNO> 120600 </DOCNO>
Radio Emission from the Composite Supernova Remnant G326.3-1.8


  High resolution radio observations of the composite supernova remnant (SNR)
G326.3-1.8 or MSH 15-56 with the Australia Telescope Compact Array show details
of both the shell and the bright plerion which is offset about 1/3 of the
distance from the center of the SNR to the shell. The shell appears to be
composed of thin filaments, typical of older shell SNRs. The central part of
the elongated plerion is composed of a bundle of parallel ridges which bulge
out at the ends and form a distinct ring structure on the northwestern end. The
magnetic field with a strength of order 45 microGauss, is directed along the
axis of the ridges but circles around the northwestern ring. This plerion is
large and bright in the radio but is not detected in x-ray or optical
wavelengths. There is, however, a faint hard x-ray feature closer to the shell
outside the plerion. Perhaps if the supernova explosion left a rapidly moving
magnetar with large energy input but initially rapid decay of both relativistic
particles and magnetic field, the observed differences with wavelength could be
explained.

</DOC>
<DOC>
<DOCNO> 8921 </DOCNO>
Macroscopic Evolution of Particle Systems with Short and Long Range


  We consider a lattice gas with general short range interactions and a Kac
potential $J_\gamma({r})$ of range $\gamma^{-1}$, $\gamma>0$, evolving via
particles hopping to nearest neighbor empty sites with rates which satisfy
detailed balance with respect to the equilibrium measure. Scaling space like
$\gamma^{-1}$ and time like $\gamma^{-2}$, we prove that in the limit $\gamma
\to 0$ the macroscopic density profile $\rho({r},t)$ satisfies a
integro-differential equation which is in the form of the gradient flux of the
energy functional $\cal F$, with a mobility given by the Einstein relation
Beside a regularity condition on J, the only requirement for this result is
that the reference system satisfy the hypotheses of the Varadhan--Yau Theorem
leading to the equation for $J\equiv 0$. Therefore the equation holds also if
$\cal F$ achieves its minimum on non constant density profiles and this
includes the cases in which {\sl phase segregation} occurs. Using the same
techniques we also derive hydrodynamic equations for the densities of a two
component A-B mixture with long range repulsive interactions between A and B
particles. The equations for the densities $\rho_A$ and $\rho_B$ are again in
the form of the gradient flux. They describe, at low temperatures, the demixing
transition in which segregation takes place via vacancies, i.e. jumps to empty
sites. In the limit of very few vacancies the problem becomes similar to phase
segregation in a continuum system in the so called incompressible limit.

</DOC>
<DOC>
<DOCNO> 150619 </DOCNO>
A Note on Interactions of (Non-Commutative) Instantons Via AdS/CFT


  We consider the interaction between instantons and anti-instantons in
four-dimensional N=4 super-Yang-Mills theory at large N and large 't Hooft
coupling as described by D-instantons via AdS/CFT duality. We give an estimate
of the strength of the interaction in various regimes. We discuss also the case
of Non-Commutative super Yang-Mills theory where the interaction between
instantons and anti-instantons can be used as a way to probe the locality
properties of the theory in the supergravity picture, without explicit
reference to the definition of local operators.

</DOC>
<DOC>
<DOCNO> 40348 </DOCNO>
Rare Kaon Decays


  The current status of the study of rare kaon decays is reviewed. Future
prospects are discussed.

</DOC>
<DOC>
<DOCNO> 13177 </DOCNO>
First-principles prediction of structure, energetics, formation


  A number of diverse bulk properties of the zincblende and wurtzite III-V
nitrides AlN, GaN, and InN, are predicted from first principles within density
functional theory using the plane-wave ultrasoft pseudopotential method, within
both the LDA (local density) and GGA (generalized gradient) approximations to
the exchange-correlation functional. Besides structure and cohesion, we study
formation enthalpies (a key ingredient in predicting defect solubilities and
surface stability), spontaneous polarizations and piezoelectric constants
(central parameters for nanostructure modeling), and elastic constants. Our
study bears out the relative merits of the two density functional approaches in
describing diverse properties of the III-V nitrides (and of the parent species
N$_2$, Al, Ga, and In), and leads us to conclude that the GGA approximation,
associated with high-accuracy techniques such as multiprojector ultrasoft
pseudopotentials or modern all-electron methods, is to be preferred in the
study of III-V nitrides.

</DOC>
<DOC>
<DOCNO> 8623 </DOCNO>
Ab initio Hartree-Fock Born effective charges of LiH, LiF, LiCl, NaF,


  We use the Berry-phase-based theory of macroscopic polarization of dielectric
crystals formulated in terms of Wannier functions, and state-of-the-art
Gaussian basis functions, to obtain benchmark ab initio Hartree-Fock values of
the Born effective charges of ionic compounds LiH, LiF, LiCl, NaF, and NaCl. We
find excellent agreement with the experimental values for all the compounds
except LiCl and NaCl, for which the disagreement with the experiments is close
to 10% and 16%, respectively. This may imply the importance of many-body
effects in those systems.

</DOC>
<DOC>
<DOCNO> 85482 </DOCNO>
A No-Go Theorem About Rotation in Relativity Theory


  Within the framework of general relativity, in some cases at least, it is a
delicate and interesting question just what it means to say that an extended
body is or is not "rotating". It is so for two reasons. First, one can easily
think of different criteria of rotation. Though they agree if the background
spacetime structure is sufficiently simple, they do not do so in general.
Second, none of the criteria fully answers to our classical intuitions. Each
one exhibits some feature or other that violates those intuitions in a
significant and interesting way. The principal goal of the paper is to make the
second claim precise in the form of a modest no-go theorem.

</DOC>
<DOC>
<DOCNO> 123017 </DOCNO>
Helicity in Hydro and MHD Reconnection


  Helicity, a measure of the linkage of flux lines, has subtle and largely
unknown effects upon dynamics. Both magnetic and hydrodynamic helicity are
conserved for ideal systems and could suppress nonlinear dynamics. What
actually happens is not clear because in a fully three-dimensional system there
are additional channels whereby intense, small-scale dynamics can occur. This
contribution shows one magnetic and one hydrodynamic case where for each the
presence of helicity does not suppress small-scale intense dynamics of the type
that might lead to reconnection.

</DOC>
<DOC>
<DOCNO> 151732 </DOCNO>
The UV and IR Origin of Nonabelian Chiral Gauge Anomalies on


  We discuss both the UV and IR origin of the one-loop triangle gauge anomalies
for noncommutative nonabelian chiral gauge theories with fundamental, adjoint
and bi-fundamental fermions for U(N) groups. We find that gauge anomalies only
come from planar triangle diagrams, the non-planar triangle contributions
giving rise to no breaking of the Ward identies. Generally speaking, theories
with fundamental and bi-fundamental chiral matter are anomalous. Theories with
only adjoint chiral fermions are anomaly free.

</DOC>
<DOC>
<DOCNO> 118875 </DOCNO>
A robust method for fitting peculiar velocity field models


  We present a new method for fitting peculiar velocity models to complete flux
limited magnitude-redshifts catalogues, using the luminosity function of the
sources as a distance indicator.The method is characterised by its robustness.
In particular, no assumptions are made concerning the spatial distribution of
sources and their luminosity function. Moreover, selection effects in redshift
are allowed. Furthermore the inclusion of additional observables correlated
with the absolute magnitude -- such as for example rotation velocity
information as described by the Tully-Fisher relation -- is straightforward.
  As an illustration of the method, the predicted IRAS peculiar velocity model
characterised by the density parameter beta is tested on two samples. The
application of our method to the Tully-Fisher MarkIII MAT sample leads to a
value of beta=0.6 \pm 0.125, fully consistent with the results obtained
previously by the VELMOD and ITF methods on similar datasets. Unlike these
methods however, we make a very conservative use of the Tully-Fisher
information. Specifically, we require to assume neither the linearity of the
Tully-Fisher relation nor a gaussian distribution of its residuals. Moreover,
the robustness of the method implies that no Malmquist corrections are
required.
  A second application is carried out, using the fluxes of the IRAS 1.2 Jy
sample as the distance indicator. In this case the effective depth of the
volume in which the velocity model is compared to the data is almost twice the
effective depth of the MarkIII MAT sample. The results suggest that the
predicted IRAS velocity model, while successful in reproducing locally the
cosmic flow, fails to describe the kinematics on larger scales.

</DOC>
<DOC>
<DOCNO> 119206 </DOCNO>
Weak Gravitational Lensing Bispectrum


  Weak gravitational lensing observations probe the spectrum and evolution of
density fluctuations and the cosmological parameters which govern them. The
non-linear evolution of large scale structure produces a non-Gaussian signal
which is potentially observable in galaxy shear data. We study the three-point
statistics of the convergence, specifically the bispectrum, using the dark
matter halo approach which describes the density field in terms of correlations
between and within dark matter halos. Our approach allows us to study the
effect of the mass distribution in observed fields, in particular the bias
induced by the lack of rare massive halos (clusters) in observed fields. We
show the convergence skewness is primarily due to rare and massive dark matter
halos with skewness converging to its mean value only if halos of mass M >
10^15 M_\sun are present. This calculational method can in principle be used to
correct for such a bias as well as to search for more robust statistics related
to the two and three point correlations.

</DOC>
<DOC>
<DOCNO> 150663 </DOCNO>
Thermodynamics of Field Theories from Spinning Branes


  We discuss general spinning p-branes of string and M-theory and use their
thermodynamics along with the correspondence between near-horizon brane
solutions and field theories with 16 supercharges to describe the thermodynamic
behavior of these theories in the presence of voltages under the R-symmetry.
The thermodynamics is used to provide two pieces of evidence in favor of a
smooth interpolation function between the free energy at weak and strong
coupling of the field theory. (i) A computation of the boundaries of stability
shows that for the D2, D3, D4, M2 and M5-branes the critical values of Omega/T
in the two limits are remarkably close and (ii) The tree-level R^4 corrections
to the spinning D3-brane generate a decrease in the free energy at strong
coupling towards the weak coupling result. We also comment on the
generalization to spinning brane bound states and their thermodynamics, which
are relevant for non-commutative field theories.

</DOC>
<DOC>
<DOCNO> 116522 </DOCNO>
Precision measurements of sodium-sodium and sodium-noble gas molecular


  Experimental apparatus and measurement technique are described for precision
absorption measurements in sodium - noble gas mixtures. The absolute absorption
coefficient is measured in the wavelength range from 425 nm to 760 nm with 2%
uncertainty and spectral resolution of 0.02 nm. The precision is achieved by
using a specially designed absorption cell with an accurately defined
absorption path length, low noise CCD detector and double-beam absorption
measurement scheme. The experimental set-up and the cell design details are
given. Measurements of sodium atomic number density with 5% uncertainty
complement absorption coefficient measurements and allow derivation of the
reduced absorption coefficients for certain spectral features. The sodium
atomic number density is measured using the anomalous dispersion method. The
accuracy of this method is improved by employing a least-squares fit to the
interference image recorded with CCD detector and the details of this technique
are given. The measurements are aimed at stringent testing of theoretical
calculations and improving the values of molecular parameters used in
calculations.

</DOC>
<DOC>
<DOCNO> 178680 </DOCNO>
J/psi suppression in ultrarelativistic nuclear collisions


  Using a multiphase transport model, we study the relative importance of J/psi
suppression mechanisms due to plasma screening, gluon scattering, and hadron
absorption in heavy ion collisions at the Relativistic Heavy Ion Collider. We
find that for collisions between heavy nuclei such as Au+Au, both plasma
screening and gluon scattering are important. As a result, the effect due to
absorption by hadrons becomes relatively minor. The final J/psi survival
probability in these collisions is only a few percent. In the case of
collisions between light nuclei such as S+S, the effect of plasma screening is,
however, negligible in spite of the initial high parton density. The final
J/psi survival probability thus remains appreciable after comparable absorption
effects due to gluons and hadrons.

</DOC>
<DOC>
<DOCNO> 84194 </DOCNO>
Regularity of Horizons and The Area Theorem


  We prove that the area of sections of future event horizons in space-times
satisfying the null energy condition is non-decreasing towards the future under
any one of the following circumstances: 1) the horizon is future geodesically
complete; 2) the horizon is a black hole event horizon in a globally hyperbolic
space-time and there exists a conformal completion with a ``H-regular'' Scri
plus; 3) the horizon is a black hole event horizon in a space-time which has a
globally hyperbolic conformal completion. (Some related results under less
restrictive hypotheses are also established.) This extends a theorem of
Hawking, in which piecewise smoothness of the event horizon seems to have been
assumed. No assumptions about the cosmological constant or its sign are made.
We prove smoothness or analyticity of the relevant part of the event horizon
when equality in the area inequality is attained - this has applications to the
theory of stationary black holes, as well as to the structure of compact Cauchy
horizons. In the course of the proof we establish several new results
concerning the differentiability properties of horizons.

</DOC>
<DOC>
<DOCNO> 71193 </DOCNO>
QCD Sum Rules, a Modern Perspective


  An introduction to the method of QCD sum rules is given for those who want to
learn how to use this method. Furthermore, we discuss various applications of
sum rules, from the determination of quark masses to the calculation of
hadronic form factors and structure functions. Finally, we explain the idea of
the light-cone sum rules and outline the recent development of this approach.

</DOC>
<DOC>
<DOCNO> 117250 </DOCNO>
Extension of Kohn-Sham theory to excited states by means of an


  Early work extending the Kohn-Sham theory to excited states utilized an
ensemble average of the Hamiltonian considered as a functional of the
corresponding average density. We propose and develop an alternative that
utilizes the matrix elements of the density operator taken between any two
states of the included space. The new theory is also based on a variational
principle for the trace of the Hamiltonian over a selected space of states
viewed, however, as a functional of the associated array of matrix elements of
the density. It leads to a matrix generalization of Kohn-Sham theory. To
illustrate the formalism, we study a suitably defined weak-coupling limit and
derive from it an eigenvalue equation that has the form of the random phase
approximation. The result can be identified with a similar equation derived
directly from the time-dependent Kohn-Sham equation that has been applied
recently with considerable success to molecular excitations. We prove, within
the defined approximations, that the eigenvalues can be interpreted as true
excitation energies.

</DOC>
<DOC>
<DOCNO> 101679 </DOCNO>
Where the Slopes Are


  Fix a prime number p and choose, once and for all, an embedding of the
algebraic closure of Q into Qp. Let k and N be integers, and suppose N is not
divisible by p. If f is a modular form of weight k, level N, and trivial
character which is an eigenform for the p-th Hecke operator Tp, we define the
slope of f to be the p-adic valuation of the eigenvalue of Tp. This paper
reports on computations that suggest that there is quite a lot of structure to
the set of slopes for eigenforms of varying weight k. In particular, we find
that the slopes are often smaller than expected, that they are almost always
integers, that there is evidence of a connection between fractional slopes and
slopes which are "bigger than usual", and that there are some hints of a
connection to the theory of theta-cycles.

</DOC>
<DOC>
<DOCNO> 117824 </DOCNO>
The Fornax Spectroscopic Survey I. Survey Strategy and Preliminary


  The Fornax Spectroscopic Survey will use the Two degree Field spectrograph
(2dF) of the Anglo-Australian Telescope to obtain spectra for a complete sample
of all 14000 objects with 16.5<=Bj<=19.7 in a 12 square degree area centred on
the Fornax Cluster. By selecting all objects---both stars and
galaxies---independent of morphology, we cover a much larger range of surface
brightness and scale size than previous surveys. In this paper we present
results from the first 2dF field. Redshift distributions and velocity
structures are shown for all observed objects in the direction of Fornax,
including Galactic stars, galaxies in and around the Fornax Cluster, and for
the background galaxy population. The velocity data for the stars show the
contributions from the different Galactic components, plus a small tail to high
velocities. We find no galaxies in the foreground to the cluster in our 2dF
field. The Fornax Cluster is clearly defined kinematically. The mean velocity
from the 26 cluster members having reliable redshifts is 1560+/-80 km/s. They
show a velocity dispersion of 380+/-50 km/s. Large-scale structure can be
traced behind the cluster to a redshift beyond z=0.3. Background compact
galaxies and low surface brightness galaxies are found to follow the general
galaxy distribution.

</DOC>
<DOC>
<DOCNO> 13249 </DOCNO>
Pair fluctuation induced pseudogap in the normal phase of the


  One-particle spectral properties in the normal phase of the two-dimensional
attractive Hubbard model are investigated in the weak coupling regime using the
non-selfconsistent T-matrix approximation. The corresponding equations are
evaluated numerically directly on the real frequency axis. For temperatures
sufficiently close to the superconducting transition temperature a pseudogap in
the one-particle spectral function is observed, which can be assigned to the
increasing importance of pair fluctuations.

</DOC>
<DOC>
<DOCNO> 116256 </DOCNO>
Canonical momenta indicators of financial markets and neocortical EEG


  A paradigm of statistical mechanics of financial markets (SMFM) is fit to
multivariate financial markets using Adaptive Simulated Annealing (ASA), a
global optimization algorithm, to perform maximum likelihood fits of
Lagrangians defined by path integrals of multivariate conditional
probabilities. Canonical momenta are thereby derived and used as technical
indicators in a recursive ASA optimization process to tune trading rules. These
trading rules are then used on out-of-sample data, to demonstrate that they can
profit from the SMFM model, to illustrate that these markets are likely not
efficient. This methodology can be extended to other systems, e.g.,
electroencephalography. This approach to complex systems emphasizes the utility
of blending an intuitive and powerful mathematical-physics formalism to
generate indicators which are used by AI-type rule-based models of management.

</DOC>
<DOC>
<DOCNO> 101843 </DOCNO>
On a conjecture of Atiyah


  In this note we explain how the computation of the spectrum of the
lamplighter group from \cite{Grigorchuk-Zuk(2000)} yields a counterexample to a
strong version of the Atiyah conjectures about the range of $L^2$-Betti numbers
of closed manifolds.

</DOC>
<DOC>
<DOCNO> 70775 </DOCNO>
Heavy Quarkonium Physics beyond the Next-to-Next-to-Leading Order of


  In this talk I briefly review the recent progress in calculation of the high
order corrections to the parameters of the nonrelativistic heavy
quark-antiquark system in the effective theory approach.

</DOC>
<DOC>
<DOCNO> 84235 </DOCNO>
Nonexistence of conformally flat slices of the Kerr spacetime


  Initial data for black hole collisions are commonly generated using the
Bowen-York approach based on conformally flat 3-geometries. The standard
(constant Boyer-Lindquist time) spatial slices of the Kerr spacetime are not
conformally flat, so that use of the Bowen-York approach is limited in dealing
with rotating holes. We investigate here whether there exist foliations of the
Kerr spacetime that are conformally flat. We limit our considerations to
foliations that are axisymmetric and that smoothly reduce in the Schwarzschild
limit to slices of constant Schwarzschild time. With these restrictions, we
show that no conformally flat slices can exist.

</DOC>
<DOC>
<DOCNO> 150984 </DOCNO>
On the Operator Product Expansion in Noncommutative Quantum Field Theory


  Motivated by the mixing of UV and IR effects, we test the OPE formula in
noncommutative field theory. First we look at the renormalization of local
composite operators, identifying some of their characteristic IR/UV
singularities. Then we find that the product of two fields in general cannot be
described by a series expansion of single local operator insertions.

</DOC>
<DOC>
<DOCNO> 151410 </DOCNO>
On the Relationship between the Rozansky-Witten and the 3-Dimensional


  The Seiberg-Witten analysis of the low-energy effective action of d=4 N=2 SYM
theories reveals the relation between the Donaldson and Seiberg-Witten (SW)
monopole invariants. Here we apply analogous reasoning to d=3 N=4 theories and
propose a general relationship between Rozansky-Witten (RW) and 3-dimensional
Abelian monopole invariants. In particular, we deduce the equality of the SU(2)
Casson invariant and the 3-dimensional SW invariant (this includes a special
case of the Meng-Taubes theorem relating the SW invariant to Milnor torsion).
Since there are only a finite number of basic RW invariants of a given degree,
many different topological field theories can be used to represent essentially
the same topological invariant. This leads us to advocate using higher rank
Abelian gauge theories to shed light on the higher (non-Abelian) RW invariants
and we write down candidate higher rank SW equations.

</DOC>
<DOC>
<DOCNO> 10464 </DOCNO>
Strongly reduced gap in the zigzag spin chain with a ferromagnetic


  We study a spin 1/2 Heisenberg zigzag spin chain model near decoupled two
chains. Taking into account a symmetry breaking perturbation, we discuss the
existence of an energy gap in the ferromagnetic interchain coupling as well as
the antiferromagnetic one. In the ferromagnetic model, a marginally relevant
fixed line reduces the gap strongly, so that the correlation length becomes an
astronomical length scale even in order 1 coupling. This result agrees with
density matrix renormalization group results.

</DOC>
<DOC>
<DOCNO> 68936 </DOCNO>
Lepton Number Violation in Supersymmetric Grand Unified Theories


  We argue that the nature of the global conservation laws in Supersymmetric
Grand Unified Theories is determined by the basic vacuum configuration in the
model rather than its Lagrangian. It is shown that the suppression of baryon
number violation in a general (R-parity violating) superpotential can naturally
appear in some extended SU(N) SUSY GUTs which, among other degenerate
symmetry-breaking vacua, have a missing VEV vacuum configuration giving a
solution to the doublet-triplet splitting problem. We construct SU(7) and SU(8)
GUTs where the effective lepton number violating couplings immediately evolve,
while the baryon number non-conserving ones are safely projected out as the GUT
symmetry breaks down to that of the MSSM. However at the next stage, when SUSY
breaks, the radiative corrections shift the missing VEV components to some
nonzero values of order M_{SUSY}, thereby inducing the ordinary Higgs doublet
mass, on the one hand, and tiny baryon number violation, on the other. So, a
missing VEV solution to the gauge hierarchy problem leads at the same time to a
similar hierarchy of baryon vs lepton number violation.

</DOC>
<DOC>
<DOCNO> 99864 </DOCNO>
Precise Propagation of Upper and Lower Probability Bounds in System P


  In this paper we consider the inference rules of System P in the framework of
coherent imprecise probabilistic assessments. Exploiting our algorithms, we
propagate the lower and upper probability bounds associated with the
conditional assertions of a given knowledge base, automatically obtaining the
precise probability bounds for the derived conclusions of the inference rules.
This allows a more flexible and realistic use of System P in default reasoning
and provides an exact illustration of the degradation of the inference rules
when interpreted in probabilistic terms. We also examine the disjunctive Weak
Rational Monotony of System P+ proposed by Adams in his extended probability
logic.

</DOC>
<DOC>
<DOCNO> 118090 </DOCNO>
Compact Stellar Systems in the Fornax Cluster: Super-massive Star


  We describe a population of compact objects in the centre of the Fornax
Cluster which were discovered as part of our 2dF Fornax Spectroscopic Survey.
These objects have spectra typical of old stellar systems, but are unresolved
on photographic sky survey plates. They have absolute magnitudes -13<Mb<-11, so
they are 10 times more luminous than any Galactic globular clusters, but
fainter than any known compact dwarf galaxies. These objects are all within 30
arcminutes of the central galaxy of the cluster, NGC 1399, but are distributed
over larger radii than the globular cluster system of that galaxy. We suggest
that these objects are either super-massive star clusters (intra-cluster
globular clusters or tidally stripped nuclei of dwarf galaxies) or a new type
of low-luminosity compact elliptical dwarf (M32-type) galaxy. The best way to
test these hypotheses will be to obtain high resolution imaging and
high-dispersion spectroscopy to determine their structures and mass-to-light
ratios. This will allow us to compare them to known compact objects and
establish if they represent a new class of hitherto unknown stellar system.

</DOC>
<DOC>
<DOCNO> 116805 </DOCNO>
Two large-area anode-pad MICROMEGAS chambers as the basic elements of a


  The design of a detector based on MICROMEGAS (MICRO MEsh GAseous Structure)
technology is presented. Our detector is characterized by a large active area
of 398(\times)281 mm(^{2}), a pad read-out with 20(\times)22 mm(^{2})
segmentation, and an uniform amplification gap obtained by insulating spacers
(100 (\mu)m high and 200 (\mu)m in diameter). The performances of several
prototypes have been evaluated under irradiation with secondary beams of 2
GeV/c momentum charged pions and electrons. We consider such a detector as the
basic element for a pre-shower detector to equip the PHOton Spectrometer (PHOS)
of the ALICE experiment. Its assets are modularity, small amount of material,
robustness and low cost.

</DOC>
<DOC>
<DOCNO> 122689 </DOCNO>
The Deuterium to Hydrogen Abundance Ratio Towards a Fourth QSO:


  We report the measurement of the primordial D/H abundance ratio towards QSO
\object. The column density of the hydrogen in the $z \simeq 2.536$ Lyman limit
system is high, \lnhi $= 19.422 \pm 0.009$ \cmm, allowing for the deuterium to
be seen in 5 Lyman series transitions. The measured value of the D/H ratio
towards QSO \object is found to be D/H$ = 2.54 \pm 0.23 \times 10^{-5}$. The
metallicity of the system showing D/H is found to be $\simeq 0.01$ solar,
indicating that the measured D/H is the primordial D/H within the measurement
errors. The gas which shows D/H is neutral, unlike previous D/H systems which
were more highly ionized. Thus, the determination of the D/H ratio becomes more
secure since we are measuring it in different astrophysical environments, but
the error is larger because we now see more dispersion between measurements.
Combined with prior measurements of D/H, the best D/H ratio is now D/H$ = 3.0
\pm 0.4 \times 10^{-5}$, which is 10% lower than the previous value. The new
values for the baryon to photon ratio, and baryonic matter density derived from
D/H are $\eta = 5.6 \pm 0.5 \times 10^{-10} $ and \ob $=0.0205 \pm 0.0018$
respectively.

</DOC>
<DOC>
<DOCNO> 123037 </DOCNO>
The Gaseous Environment of Seyfert Galaxies


  The VLA has been used to image HI in a heterogeneous sample of nine Seyferts
as part of a continuing investigation of the role of galactic host gas in the
triggering and fuelling of nuclear activity. Where previous single-dish
observations indicated complex, poorly understood kinematics, improved angular
resolution and sensitivity reveal tidal tails and intragroup gas, distinguish
dwarfs from main disks and resolve non-linear gas dynamical features such as
shocks in bars. Seyferts may be abnormally gas-rich, but a larger,
statistically significant comparison of HI properties of normal and active
galaxies is now required.

</DOC>
<DOC>
<DOCNO> 122364 </DOCNO>
Globular Clusters as Probes of the Virgo gE NGC 4472


  We present radial velocities for 144 globular clusters around the Virgo gE
NGC 4472 (M49), and ages and metallicities from co-added spectra of 131
clusters. We confirm our earlier finding that the metal-poor clusters have a
significantly higher velocity dispersion than the metal-rich clusters, and we
find little or no rotation in the metal-rich clusters. The velocity dispersion
profile is consistent with isotropic orbits for the clusters and the NGC 4472
mass distribution inferred from X-ray data. Our sample of clusters spans a
metallicity range of -1.6 < [Fe/H] < 0 dex. The metal-poor and metal-rich
cluster populations are coeval within the errors, and all clusters are older
than 6 Gyr at 95% confidence. Our findings are consistent with a merger origin
for NGC 4472, but other elliptical formation models cannot be ruled out.

</DOC>
<DOC>
<DOCNO> 170526 </DOCNO>
The Quantum-Classical Transition in Nonlinear Dynamical Systems


  Viewed as approximations to quantum mechanics, classical evolutions can
violate the positive-semidefiniteness of the density matrix. The nature of this
violation suggests a classification of dynamical systems based on
classical-quantum correspondence; we show that this can be used to identify
when environmental interaction (decoherence) will be unsuccessful in inducing
the quantum-classical transition. In particular, the late-time Wigner function
can become positive without any corresponding approach to classical dynamics.
In the light of these results, we emphasize key issues relevant for experiments
studying the quantum-classical transition.

</DOC>
<DOC>
<DOCNO> 71669 </DOCNO>
Symmetries Shared by Particle Physics and Quantum Optics


  It is known that two coupled harmonic oscillators can support the symmetry
group as rich as O(3,3) which corresponds to the Lorentz group applicable to
three space-like and three time-like coordinates. This group contains many
subgroups, including O(3), O(3,2), O(2,1) which are already familiar to us. In
this report, we discuss the symmetry of O(1,1) which plays pivotal roles in
quantum optics and particle physics. For this one-parameter group, a
full-fledged group theory is not necessary, and we can start the discussion
from the Hamiltonian of the coupled oscillator system. It is shown first that,
from the group theoretical point of view, the squeeze state of light is a
representation of this O(1,1) group. It is then shown that the same
mathematical device supports three seemingly different ideas of Feynman, namely
the parton model, the relativistic quark model for hadrons, and the ``rest of
the universe'' in connection with the density matrix. If these three theories
are combined, they produce a covariant picture of Feynman's parton model with a
built-in decoherence mechanism.

</DOC>
<DOC>
<DOCNO> 39758 </DOCNO>
Study of b -> u l nu Decays with an Inclusive Generator


  A generator for inclusive b -> u l nu decays has been developed. Different
prescriptions have been applied to describe the kinematics of the b-quark
inside the hadron and the generation of the hadronic final states. Results are
presented with particular attention to the invariant mass of the hadronic
system recoiling against the lepton and its resonance decomposition. These
studies are of special relevance for the extraction of Vub from semileptonic B
decays at LEP and at B factories.

</DOC>
<DOC>
<DOCNO> 83155 </DOCNO>
dcs: An Implementation of DATALOG with Constraints


  Answer-set programming (ASP) has emerged recently as a viable programming
paradigm. We describe here an ASP system, DATALOG with constraints or DC, based
on non-monotonic logic. Informally, DC theories consist of propositional
clauses (constraints) and of Horn rules. The semantics is a simple and natural
extension of the semantics of the propositional logic. However, thanks to the
presence of Horn rules in the system, modeling of transitive closure becomes
straightforward. We describe the syntax, use and implementation of DC and
provide experimental results.

</DOC>
<DOC>
<DOCNO> 11584 </DOCNO>
Four-state quantum chain as a model of sequence evolution


  A variety of selection-mutation models for DNA (or RNA) sequences, well known
in molecular evolution, can be translated into a model of coupled Ising quantum
chains. This correspondence is used to investigate the genetic variability and
error threshold behaviour in dependence of possible fitness landscapes. In
contrast to the two-state models treated hitherto, the model explicitly takes
the four-state nature of the nucleotide alphabet into account and allowes for
the distinction of mutation rates for the different base substitutions, as
given by standard mutation schemes of molecular phylogeny. As a consequence of
this refined treatment, new phase diagrams for the error threshold behaviour
are obtained, with appearance of a novel phase in which the nucleotide ordering
of the wildtype sequence is only partially conserved. Explicit analytic and
numeric results are presented for evolution dynamics and equilibrium behaviour
in a number of accessible situations, such as quadratic fitness landscapes and
the Kimura 2 parameter mutation scheme.

</DOC>
<DOC>
<DOCNO> 169640 </DOCNO>
Entangled Chains


  Consider an infinite collection of qubits arranged in a line, such that every
pair of nearest neighbors is entangled: an "entangled chain." In this paper we
consider entangled chains with translational invariance and ask how large one
can make the nearest neighbor entanglement. We find that it is possible to
achieve an entanglement of formation equal to 0.285 ebits between each pair of
nearest neighbors, and that this is the best one can do under certain
assumptions about the state of the chain.

</DOC>
<DOC>
<DOCNO> 100481 </DOCNO>
An Elementary Introduction to Groups and Representations


  These notes give an elementary introduction to Lie groups, Lie algebras, and
their representations. Designed to be accessible to graduate students in
mathematics or physics, they have a minimum of prerequisites. Topics include
definitions and examples of Lie groups and Lie algebras, the relationship
between Lie groups and Lie algebras via the exponential mapping, the basics of
representations theory, the Baker-Campbell-Hausdorff formula, a detailed study
of the representations of SU(3), and a brief survey of the representation
theory of general semisimple groups.

</DOC>
<DOC>
<DOCNO> 67830 </DOCNO>
A D-moduli problem?


  We point out a generic problem in string-inspired supergravity models with an
anomalous $U(1)_X$. A large number of matter multiplets charged under $U(1)_X$
remain massless above the supersymmetry-breaking scale because of degeneracy of
vacua solving the D-flatness conditions. A toy model is analyzed as an
illustration of the mechanism; we find the surprising result that many scalars
remain massless after supersymmetry-breaking in a hidden sector.

</DOC>
<DOC>
<DOCNO> 119850 </DOCNO>
Superbubbles and the Galactic evolution of Li, Be and B


  From a recent re-analysis of the available data, Be and B Galactic evolution
appears to show evidence for a two-slope behaviour with respect to O. The
inferred Be/O abundance ratio in halo stars is constant at very low metallicity
(primary behaviour) and increases proportionally to O/H at high metallicity
(secondary behaviour). We show that this can be explained in the framework of
one single model, the `superbubble model', in which Li, Be and B are produced
by spallation reactions induced by energetic particles accelerated out of a
mixture of supernova (SN) ejecta and ambient interstellar medium inside
superbubbles (SBs). All the qualitative and quantitative constraints, including
the energetics, the value of the transition metallicity and the 6Li/9Be
isotopic ratio, are satisfied provided that the energetic particles have a
spectrum flattened at low energy (in E^-1) and that the proportion of the SN
ejecta inside SBs is of the order of a few percent. This lends support to
Bykov's acceleration mechanism inside SBs and to the SB dynamical evolution
model of Mac Low & McCray (1988).

</DOC>
<DOC>
<DOCNO> 70610 </DOCNO>
Gravitational Stability and Screening Effect from D Extra Timelike


  We study (3+1)+D dimensional spacetime, where D extra dimensions are
timelike. Compactification of the D timelike dimensions leads to tachyonic
Kaluza-Klein gravitons. We calculate the gravitational self-energies of massive
spherical bodies due to the tachyonic exchange, discuss their stability, and
find that the gravitational force is screened in a certain number of the extra
dimensions. We also derive the exact relationship between the Newton constants
in the full 4+D dimensional spacetime with the D extra times and the ordinary
Newton constant of our 4 dimensional world.

</DOC>
<DOC>
<DOCNO> 70050 </DOCNO>
Next-to-leading virtual photon - Reggeized gluon interaction


  We present the results of the calculation of the one-loop correction to the
effective vertex for the quark-antiquark pair production in collisions of the
virtual photon with the Reggeized gluon. This vertex is supposed then to be
used for the calculation of the virtual photon impact factor, which is
extremely important, for instance, for the description of the small $x$ deep
inelastic scattering in the BFKL approach.

</DOC>
<DOC>
<DOCNO> 84842 </DOCNO>
Black Hole entropy in D=2+1 dimensions from extended Chern-Simons term


  We study the contribution to entropy of Black Holes in D=2+1 dimensions from
an extension of the Chern Simons theory including higher derivative in a curved
space-time.

</DOC>
<DOC>
<DOCNO> 151574 </DOCNO>
Gauge invariant derivative expansion of the effective action at finite


  A method is presented for the computation of the one-loop effective action at
finite temperature and density. The method is based on an expansion in the
number of spatial covariant derivatives. It applies to general background field
configurations with arbitrary internal symmetry group and space-time
dependence. Full invariance under small and large gauge transformations is
preserved without assuming stationary or Abelian fields nor fixing the gauge.
The method is applied to the computation of the effective action of spin zero
particles in 2+1 dimensions at finite temperature and density and in presence
of background gauge fields. The calculation is carried out through second order
in the number of spatial covariant derivatives. Some limiting cases are worked
out.

</DOC>
<DOC>
<DOCNO> 170735 </DOCNO>
Highly efficient photon-pair source using a Periodically Poled Lithium


  We report on a new kind of correlated photon-pair source based on a waveguide
integrated on a Periodically Poled Lithium Niobate substrate. Using a pump
laser of a few micro-Watts at 657 nm, we generate degenerate photon-pairs at
1314 nm. Detecting about 1500 coincidences per second, we can infer a
conversion rate of 10-6 pairs per pump photon, which is four orders of
magnitude higher than that obtained with previous bulk sources. These results
are very promising for the realization of sources for quantum communication and
quantum metrology experiments requiring a high signal-to-noise ratio or working
with more than one photon-pair at a time.

</DOC>
<DOC>
<DOCNO> 151510 </DOCNO>
Is a classical description of stable non-BPS D-branes possible?


  We study the classical geometry produced by a stack of stable (i.e. tachyon
free) non-BPS D-branes present in K3 compactifications of type II string
theory. This classical representation is derived by solving the equations of
motion describing the low-energy dynamics of the supergravity fields which
couple to the non-BPS state. Differently from what expected, this configuration
displays a singular behaviour: the space-time geometry has a repulson-like
singularity. This fact suggests that the simplest setting, namely a set of
coinciding non-interacting D-branes, is not acceptable. We finally discuss the
possible existence of other acceptable configurations corresponding to more
complicated bound states of these non-BPS branes.

</DOC>
<DOC>
<DOCNO> 13139 </DOCNO>
Driving superfluidity with photoassociation


  We theoretically examine photoassociation of a two-component Fermi degenerate
gas. Our focus is on adjusting the atom-atom interaction, and thereby
increasing the critical temperature of the BCS transition to the superfluid
state. In order to avoid spontaneous decay of the molecules, the
photoassociating light must be far-off resonance. Very high light intensities
are therefore required for effective control of the BCS transition.

</DOC>
<DOC>
<DOCNO> 119494 </DOCNO>
Black Holes and Host Galaxies of NLS1s


  Recently, reliable mass estimates for the central black holes in AGN became
feasible due to emission-line reverberation techniques. Using this method as a
calibrator, it is possible to determine black hole masses for a wide range of
AGN, in particular NLS1s. Do NLS1s have smaller black holes than ordinary
Seyfert 1 galaxies? Are their black holes smaller compared to the sizes of
their host galaxies? Do they have larger L/M ratios? Do NLS1s have hotter
accretion disks? I confront these questions with accretion disk theory and with
the data, showing that the above may well be the case.

</DOC>
<DOC>
<DOCNO> 151045 </DOCNO>
Brane solutions in strings with broken supersymmetry and dilaton


  The tachyon-free nonsupersymmetric string theories in ten dimensions have
dilaton tadpoles which forbid a Minkowski vacuum. We determine the maximally
symmetric backgrounds for the $USp(32)$ Type I string and the $SO(16)\times
SO(16)$ heterotic string. The static solutions exhibit nine dimensional
Poincar\'e symmetry and have finite 9D Planck and Yang-Mills constants. The low
energy geometry is given by a ten dimensional manifold with two boundaries
separated by a finite distance which suggests a spontaneous compactification of
the ten dimensional string theory.

</DOC>
<DOC>
<DOCNO> 101597 </DOCNO>
Equivariant Cyclic Cohomology of Hopf Module Algebras


  We introduce an equivariant version of cyclic cohomology for Hopf module
algebras. For any $H$-module algebra A, where $H$ is a Hopf algebra with $S^2 =
id_H$ we define the cocyclic module $C^{\natural}_H(A)$ and we find its
relation with cyclic cohomology of crossed product algebra $ A \rtimes H$. We
define $K_0^{H}(A)$, the equivariant K-theory group of A, and its pairing with
cyclic and periodic cyclic cohomology of $C^{\natural}_H(A)$.

</DOC>
<DOC>
<DOCNO> 118010 </DOCNO>
Observing high-redshift Supernovae in lensed galaxies


  Supernovae in distant galaxies that are gravitationally lensed by foreground
galaxy clusters make excellent cosmological candles for measuring quantities
like the density of the Universe in its various components and the Hubble
constant. Distant supernovae will be more easily detectable since foreground
cluster lenses would magnify such supernovae by up to 3-4 magnitudes. We show
that in the case of the lens cluster Abell 2218, the detectability of
high-redshift supernovae is significantly enhanced due to the lensing effects
of the cluster. Since lensed supernovae will remain point images even when
their host galaxies are stretched into arcs, the signal-to-noise ratio for
their observation will be further enhanced, typically by an order of magnitude.
We recommend monitoring well-modelled clusters with several known arclets for
the detection of cosmologically useful SNe around z=1 and beyond.

</DOC>
<DOC>
<DOCNO> 72163 </DOCNO>
On t anti-t threshold and top quark mass definition


  In this talk we discuss the process e^+e^-\to t\bar t near threshold,
calculated with NNLO accuracy as well as top quark mass definitions adequate
for the threshold. As new definition we suggest the PS-bar mass which allows to
calculate recoil corrections to the static PS mass. Using this result we
calculate the cross section of e^+e^-\to t\bar t near threshold at NNLO
accuracy adopting three alternative approaches, namely (1) fixing the pole
mass, (2) fixing the PS mass, and (3) fixing the new mass which we call the
PS-bar mass. We demonstrate that perturbative predictions for the cross section
become much more stable if we use the PS or the PS-bar mass for the
calculations. A careful analysis suggests that the top quark mass can be
extracted from a threshold scan at NLC with an accuracy of about 100 MeV.

</DOC>
<DOC>
<DOCNO> 122968 </DOCNO>
Growth of Galactic Bulges by Mergers: I. Dense Satellites


  Andredakis, Peletier & Balcells (1995) fit Sersic's law $\mu(r) \sim r^{1/n}$
to the bulges of the Balcells & Peletier (1994) galaxy sample, and infer that
$n$ drops with morphological type T from $n \approx$ 4--6 for S0 to $n=1$
(exponential) for Sc's. We use collisionless N body simulations to test the
assumption that initially the surface brightness profiles of all bulges were
exponential, and that the steepening of the profiles toward the early-types is
due to satellite accretion. The results are positive. After the accretion of a
satellite, bulge-disk fits show that the bulge grows and that the bulge profile
index $n$ increases proportional to the satellite mass. For a satellite as
massive as the bulge, $n$ rises from 1 to 4. We present kinematic diagnostics
on the remnants and disk thickening. The latter suggests that the bulge growth
must have occurred before the last formation of a thin disk in the galaxy. The
thick disks created by the merger are reminiscent of thick disks seen in
early-type edge-on galaxies.
  The efficiency of the process suggests that present day bulges of late-type
spirals showing exponential profiles cannot have grown significantly by
collisionless mergers.

</DOC>
<DOC>
<DOCNO> 40367 </DOCNO>
Measurements of Inclusive and Exclusive B Decays to Charmonium with


  Using 8.5M B-anti-B events recorded by the BABAR detector the yield of
inclusive J/psi, the branching ratios of psi(2S) and chi_C1 are presented.
Combining the charmonium state with either a K+,KS, K*+ or K*0 exclusive B
decays are reconstructed and their branching ratios determined. Using the fully
reconstructed decays, both the B0 and B+ masses and their difference is
measured. Finally the contributions of CP even and odd amplitudes in the decay
B to J/psi K* are determined from an angular analysis.

</DOC>
<DOC>
<DOCNO> 99527 </DOCNO>
Dimension estimates for Hilbert schemes and effective base point


  We obtain effective results for the global generation of pluritheta line
bundles on moduli spaces of vector bundles on curves. The main ingredient is an
independent result giving an upper bound on the dimension of the Hilbert scheme
of coherent quotients of a given vector bundle.

</DOC>
<DOC>
<DOCNO> 71103 </DOCNO>
Neutrinos and the Standard Model


  Since their "discovery" by Pauli in 1930, neutrinos have plaed a key part in
confirmation of the structure of the standard model of strong and electroweak
interactions. After reviewing ways in which this has been manifested in the
past, we discuss areas in which neutrinos continue to play this role.

</DOC>
<DOC>
<DOCNO> 10434 </DOCNO>
Statistical mechanics of semiflexible ribbon polymers


  The statistical mechanics of a ribbon polymer made up of two semiflexible
chains is studied using both analytical techniques and simulation. The system
is found to have a crossover transition at some finite temperature, from a type
of short range order to a fundamentally different sort of short range order. In
the high temperature regime, the 2-point correlation functions of the object
are identical to worm-like chains, while in the low temperature regime they are
different due to a twist structure. The crossover happens when the persistence
length of individual strands becomes comparable to the thickness of the ribbon.
In the low temperature regime, the ribbon is observed to have a novel
``kink-rod'' structure with a mutual exclusion of twist and bend in contrast to
smooth worm-like chain behaviour. This is due to its anisotropic rigidity and
corresponds to an {\it infinitely} strong twist-bend coupling. The
double-stranded polymer is also studied in a confined geometry. It is shown
that when the polymer is restricted in a particular direction to a size less
than the bare persistence length of the individual strands, it develops zigzag
conformations which are indicated by an oscillatory tangent-tangent correlation
function in the direction of confinement. Increasing the separation of the
confining plates leads to a crossover to the free behaviour, which takes place
at separations close to the bare persistence length. These results are expected
to be relevant for experiments which involve complexation of two or more stiff
or semiflexible polymers.

</DOC>
<DOC>
<DOCNO> 100699 </DOCNO>
Moduli problems of sheaves associated with oriented trees


  To every oriented tree, we associate a moduli problem for sheaves over a
projective manifold $X$. We define the corresponding notion of semistability
and establish the existence of moduli spaces. Applying the results to the tree
*->*, we obtain a GIT construction for the moduli space of holomorphic triples
of Bradlow and Garcia-Prada.

</DOC>
<DOC>
<DOCNO> 117764 </DOCNO>
The present rate of Supernovae


  We present and discuss the most recent determination of the rate of
Supernovae in the local Universe. A comparison with other results shows a
general agreement on the gross values but still significant differences on the
values of the rates of various SN rates in different kinds of galaxies. The
rate of SNe, used as a probe of Star Formation, confirms the young progenitor
scenario for SNII+Ib/c. The increasing diversity of SNe reflects also in the SN
yields which may affect the chemical evolution of the Galaxy but, because of
the limited statistics, we cannot estimate the contributions of the new
subtypes yet. It is also expected that in a few years observational
determinations of the SN rates at various look-back times will be available.

</DOC>
<DOC>
<DOCNO> 121779 </DOCNO>
Warm H2 in the Galactic center region


  We present ISO observations of several H2 pure-rotational lines (from S(0) to
S(5)) towards a sample of 16 molecular clouds distributed along the central ~
500 pc of the Galaxy. We also present C18O and 13CO J=1->0 and J=2->1
observations of these sources made with the IRAM-30m telescope. With the CO
data we derive H2 densities of 10e(3.5-4.0) cm-3 and H2 column densities of a
few 10e22 cm-2. We have corrected the H2 data for ~ 30 magnitudes of visual
extinction using a self-consistent method. In every source, we find that the H2
emission exhibits a large temperature gradient. The S(0) and S(1) lines trace
temperatures (T) of ~150 K while the S(4) and S(5) lines indicate temperatures
of ~ 600K. The warm H2 column density is typically ~1-2 x 10e22 cm-2, and is
predominantly gas with T=150 K. This is the first direct estimate of the total
column density of the warm molecular gas in the Galactic center region. These
warm H2 column densities represent a fraction of ~ 30 % of the gas traced by
the CO isotopes emission. The cooling by H2 in the warm component is comparable
to that by CO. Comparing our H2 and CO data with available ammonia NH3
observations from literature one obtains relatively high NH3 abundances of a
few 10e(-7) in both the warm and the cold gas. A single shock or
Photo-Dissociation Region (PDR) cannot explain all the observed H2 lines.
Alternatives for the heating mechanisms are discussed.

</DOC>
<DOC>
<DOCNO> 118651 </DOCNO>
Searching for AGN signatures in Mid-IR Spectra: The case of NGC1068


  We present mid-IR observations of the prototypical Seyfert 2 galaxy NGC 1068
obtained with ISOCAM between 5 and 16micron. The proximity of this galaxy
coupled with the spectro-imaging capabilities of the instrument allow us to
separate the mid-IR emission of the active galactic nucleus (AGN) from the
distinctly different emission of the circumnuclear star forming regions. The
Unidentified Infrared Bands (UIBs), which trace the starburst contribution very
well, are not detected in the spectrum of the AGN region where their carriers
could be destroyed. Moreover, the featureless continuum of the AGN exhibits a
strong hot dust component below 10micron not observed in the starburst regions.
Those two distinct mid-IR spectral properties, as well as the presence of high
excitation ionic lines such as [NeVI](7.7micron) and [NeV](14.3micron) in the
AGN spectrum, provide us with very powerful complementary tools to disentangle
AGNs from starbursts. The effects of high extinction on the mid-IR
identification of AGNs are also discussed.

</DOC>
<DOC>
<DOCNO> 12387 </DOCNO>
Hamiltonian self-adjoint extensions for (2+1)-dimensional Dirac


  We study the stationary problem of a charged Dirac particle in (2+1)
dimensions in the presence of a uniform magnetic field B and a singular
magnetic tube of flux Phi = 2 pi kappa/e. The rotational invariance of this
configuration implies that the subspaces of definite angular momentum l+1/2 are
invariant under the action of the Hamiltonian H. We show that, for l different
from the integer part of kappa, the restriction of H to these subspaces,
 H_l is essentially self-adjoint, while for l equal to the integer part of
kappa, H_l admits a one-parameter family of self-adjoint extensions (SAE). In
the later case, the functions in the domain of H_l are singular (but
square-integrable) at the origin, their behavior being dictated by the value of
the parameter gamma that identifies the SAE. We also determine the spectrum of
the Hamiltonian as a function of kappa and gamma, as well as its closure.

</DOC>
<DOC>
<DOCNO> 11166 </DOCNO>
Extinction Transition on a Pie


  Extinction transition of bacteria under forced rotation is analyzed in pie
geometry. Under convection, separation of the radial and the azimuthal degrees
of freedom is not possible, and the linearized evolution operator is
diagonalized numerically. Some characteristics scales are compared with the
results of recent experiments, and the ``integrable'' limit of the theory at
narrow growth region is analyzed.

</DOC>
<DOC>
<DOCNO> 101663 </DOCNO>
Linearization of holomorphic germs with resonant linear part


  We study the linearization problem of germs of holomorphic diffeomorphisms
with resonant linear part. The formal linearization requires in general an
infinite number of algebraic relations to be satisfied by the coefficients of
the power series defining the holomorphic germ. For a fixed germ, the
linearizing mappings are not unique, but the existence of a finite jet with a
formal divergent linearization but no convergent one forces all the other
linearizing mappings to be diverging. We consider also polynomial families
formally conjugated to a fixed resonant linear part. Then all the elements of
the family are holomorphically linearizable, or we are in the precedent
diverging situation for all but an exceptional set of parameter values of zero
$\Gamma$-capacity. In the case of maximal non-trivial resonance we prove the
optimality of Bruno condition.

</DOC>
<DOC>
<DOCNO> 69581 </DOCNO>
Big Bang in $AdS_{5}$ with external field and flat 4d Universe


  We describe spontaneous creation of the Brane World in $AdS_{5}$ with
external field. The resulting Brane World consists of a flat 4d spatially
finite expanding Universe and curved expanding "regulator" branes. No negative
tension branes are involved.

</DOC>
<DOC>
<DOCNO> 152010 </DOCNO>
Thermodynamic implications of some unusual quantum theories


  Various deformations of the position-momentum algebras operators have been
proposed. Their implications for single systems like the hydrogen atom or the
harmonic oscillator have been addressed. In this paper we investigate the
consequences of some of these algebras for macroscopic systems. The key point
of our analysis lies in the fact that the modification of the Heisenberg
uncertainty relations present in these theories changes the volume of the
elementary cell in the hamiltonian phase space and so the measure needed to
compute partition functions.
  The thermodynamics of a non interacting gas are studied for two members of
the Kempf-Mangano-Mann (K.M.M.) deformations. It is shown that the theory which
exhibits a minimal uncertainty in length predicts a new behavior at high
temperature while the one with a minimal uncertainty in momentum displays
unusual features for huge volumes. In the second model negative pressures are
obtained and mixing two different gases does not necessarily increase the
entropy . This suggests a possible violation of the second law of
thermodynamics. Potential consequences of these models in the evolution of the
early universe are briefly discussed.
  Constructing the Einstein model of a solid for the q deformed oscillator, we
find that the subset of eigenstates whose energies are bounded from above leads
to a divergent partition function.

</DOC>
<DOC>
<DOCNO> 12469 </DOCNO>
New approach to Monte Carlo calculation of buckling of supercoiled DNA


  The short supercoiled circular DNA molecules are shown to be glassy systems
and canonical Metropolis Monte Carlo simulations of the systems tend to get
stuck in local metastable energy basins. A novel Monte Carlo algorithm is
developed to alleviate the problem of ``ergodicity breaking'' of the glassy
systems, in which the Markov process is driven by an explicitly analytic weight
factor with enhanced probability in both low- and high-energy regions. To
characterize the degree of puckering of the supercoiled DNA loops, a new
quantity of aplanarity is introduced as the shortest principal axis of
configurational ellipsoid of DNA. With the suggested Monte Carlo method, the
quantitative correlation between supercoiling degree and buckling of DNA is
attained. With supercoiling stress increasing, the conformational transition
from a circle to mono-, diplo- or triple interwound superhelical structure will
take place in a successive but decreasingly abrupt mode.

</DOC>
<DOC>
<DOCNO> 10428 </DOCNO>
Noise-Activated Escape from a Sloshing Potential Well


  We treat the noise-activated escape from a one-dimensional potential well of
an overdamped particle, to which a periodic force of fixed frequency is
applied. We determine the boundary layer behavior, and the physically relevant
length scales, near the oscillating well top. We show how stochastic behavior
near the well top generalizes the behavior first determined by Kramers, in the
case without forcing. Both the case when the forcing dies away in the weak
noise limit, and the case when it does not, are examined. We also discuss the
relevance of various scaling regimes to recent optical trap experiments.

</DOC>
<DOC>
<DOCNO> 70980 </DOCNO>
Broken R Parity, Neutrino Anomalies and Collider Tests


  The solar and atmospheric neutrino anomalies constitute the only solid and
most remarkable evidence for physics beyond the Standard Model, indicating that
the lepton mixing matrix is fundamentally distinct from that describing the
quarks. Here I will report on how supersymmetry with spontaneously or
bilinearly broken R Parity provides a predictive theory for neutrino mass and
mixing which leads to a solution of neutrino anomalies which can be clearly
tested at high energy accelerators.

</DOC>
<DOC>
<DOCNO> 152541 </DOCNO>
Cosmological Perturbations in Brane Worlds: Brane Bending and


  Using a metric-based formalism to treat cosmological perturbations, we
discuss the connection between anisotropic stress on the brane and brane
bending. First we discuss gauge-transformations, and draw our attention to
gauges, in which the brane-positions remain unperturbed. We provide a unique
gauge, where perturbations both on the brane and in the bulk can be treated
with generality. For vanishing anisotropic stresses on the brane, this gauge
reduces to the generalized longitudinal gauge. We further comment on the
gravitational interaction between the branes and the bulk.

</DOC>
<DOC>
<DOCNO> 150824 </DOCNO>
Noncommutative Gauge Dynamics From The String Worldsheet


  We show how string theory can be used to reproduce the one-loop two-point
photon amplitude in noncommutative U(1) gauge theory. Using a simple
realization of the gauge theory in bosonic string theory, we extract from a
string cylinder computation in the decoupling limit the exact one loop field
theory result. The result is obtained entirely from the region of moduli space
where massless open strings dominate. Our computation indicates that the
unusual IR/UV singularities of noncommutative field theory do not come from
closed string modes in any simple way.

</DOC>
<DOC>
<DOCNO> 68211 </DOCNO>
A method for determining anomalous gauge boson couplings from e^{+}e^{-}


  We present a model-independent method for determining anomalous gauge boson
couplings from ongoing and future e^{+}e^{-} -> W^{+} W^{-} experiments. First
we generalize an already existing method, which relies on the study of four
observables constructed through appropriate projections of the unpolarized
differential cross-section. In particular, we retain both linear and quadratic
terms in the unknown couplings, and compute contributions to these observables
originating from anomalous couplings which do not separately conserve the
discrete C, P, and T symmetries. Second, we combine the above set of
observables with three additional ones, which can be experimentally obtained
from the total cross-sections for polarized final state W bosons. The resulting
set of seven observables may provide useful information for constraining, and
in some cases for fully determining, various of the possible anomalous gauge
boson couplings.

</DOC>
<DOC>
<DOCNO> 10923 </DOCNO>
Direct and indirect exciton mixing in a slightly asymmetric double


  We studied, theoretically, the optical absorption spectra for a slightly
asymmetric double quantum well (DQW), in the presence of electric and magnetic
fields. Recent experimental results for a 10.18/3.82/9.61 nm GaAs Al(_{.33}
)Ga(_{.67})As DQW show clearly the different behavior in the luminescence peaks
for the indirect exciton (IX) and left direct exciton (DX) as a function of the
external electric field. We show that the presence of a peak near the (DX)
peak, attributed to an impurity bound left (DX) in the experimental results,
could be a consequence of the non-trivial mixing between excitonic states.

</DOC>
<DOC>
<DOCNO> 100501 </DOCNO>
Affine Lie Algebras and Tame Quivers


  C.M. Ringel defined Hall algebra associated with the category of
representations of a quiver of Dynkin type and gave an explicit description of
the structure constants of the corresponding Lie algebra. We utilize functorial
properties of the Hall algebra to give a simple proof of Ringel's result, and
to generalize it to the case of a quiver of affine type.

</DOC>
<DOC>
<DOCNO> 10548 </DOCNO>
Net Charge on a Noble Gas Atom Adsorbed on a Metallic Surface


  Adsorbed noble gas atoms donate (on the average) a fraction of an electronic
charge to the substrate metal. The effect has been experimentally observed as
an adsorptive change in the electronic work function. The connection between
the effective net atomic charge and the binding energy of the atom to the metal
is theoretically explored.

</DOC>
<DOC>
<DOCNO> 10818 </DOCNO>
Off equilibrium properties of vortex creep in superconductors


  We study a model for the dynamics of vortices in type II superconductors. In
particular, we discuss glassy ``off equilibrium'' properties and ``aging'' in
magnetic creep. At low temperatures a crossover point is found, Tg, where
relaxation times seem to diverge a' la Vogel-Tamman-Fulcher. Magnetic creep
changes by crossing Tg: above Tg power law creep is found asymptotically
followed by stretched exponential saturation; below Tg the creep is logarithmic
and vortex motion strongly subdiffusive. In this region violation of time
translation invariance is found along with important dynamical scaling
properties. A thermodynamic glassy transition point can be found at a lower
temperature Tc.

</DOC>
<DOC>
<DOCNO> 84587 </DOCNO>
Large-distance behaviour of the graviton two-point function in de Sitter


  It is known that the graviton two-point function for the de Sitter invariant
"Euclidean" vacuum in a physical gauge grows logarithmically with distance in
spatially-flat de Sitter spacetime. We show that this logarithmic behaviour is
a gauge artifact by explicitly demonstrating that the same behaviour can be
reproduced by a pure-gauge two-point function.

</DOC>
<DOC>
<DOCNO> 8002 </DOCNO>
Double-exchange is not the cause of ferromagnetism in doped manganites


  The coexistence of ferromagnetism and metallic conduction in doped manganites
has long been explained by a double-exchange model in which the ferromagnetic
exchange arises from the carrier hopping. We evaluate the zero-temperature spin
stiffness D(0) and the Curie temperature T_{C} on the basis of the
double-exchange model using the measured values of the bare bandwidth W and the
Hund's rule coupling J_{H}. The calculated D(0) and T_{C} values are too small
compared with the observed ones even in the absence of interactions. A
realistic onsite interorbital Coulomb repulsion can reduce D(0) substantially
in the case of a 2-orbital model. Furthermore, experiment shows that D(0) is
simply proportional to x in La_{1-x}Sr_{x}MnO_{3} system, independent of
whether the ground state is a ferromagnetic insulator or metal. These results
strongly suggest that the ferromagnetism in manganites does not originate from
the double-exchange interaction. On the other hand, an alternative model based
on the d-p exchange can semi-quantitatively explain the ferromagnetism of doped
manganites at low temperatures.

</DOC>
<DOC>
<DOCNO> 13551 </DOCNO>
Interacting random Dirac fermions in superconducting cuprates


  We study the effects of quasiparticle interactions on disorder-induced
localization of Dirac-like nodal excitations in superconducting high-$T_c$
cuprates. As suggested by the experimental ARPES and terahertz conductivity
data in $Bi_2Sr_2CaCu_2O_{8+\delta}$, we focus on the interactions mediated by
the order parameter fluctuations near an incipient second pairing transition
$d\to d+is$. We find interaction corrections to the density of states, specific
heat, and conductivity as well as phase and energy relaxation rates and assess
the applicability of the recent localization scenarios for non-interacting
random Dirac fermions to the cuprates.

</DOC>
<DOC>
<DOCNO> 8561 </DOCNO>
Duality in the Quantum Hall Effect - the Role of Electron Spin


  At low temperatures the phase diagram for the quantum Hall effect has a
powerful symmetry arising from the Law of Corresponding States. This symmetry
gives rise to an infinite order discrete group which is a generalisation of
Kramers-Wannier duality for the two dimensional Ising model. The duality group,
which is a subgroup of the modular group, is analysed and it is argued that
there is a quantitative difference between a situation in which the spin
splitting of electron energy levels is comparable to the cyclotron energy and
one in which the spin splitting is much less than the cyclotron energy. In the
former case the group of symmetries is larger than in the latter case. These
duality symmetries are used to constrain the scaling functions of the theory
and, under an assumption of complex meromorphicity, a unique functional form is
obtained for the crossover of the conductivities between Hall states as a
function of the external magnetic field. This analytic form is shown to give
good agreement with experimental data.
  The analysis requires a consideration of the way in which longitudinal
resistivities are extracted from the experimentally measured longitudinal
resistances and a novel method is proposed for determining the correct
normalisation for the former.

</DOC>
<DOC>
<DOCNO> 12564 </DOCNO>
Magnetic relaxation phenomena and cluster glass properties of


  The dynamic magnetic properties of the distorted perovskite system
La{0.7-x}Y{x}Ca{0.3}MnO{3} (0 <= x <= 0.15) have been investigated by
ac-susceptibility and dc magnetization measurements, with emphasis on
relaxation and aging studies. They evidence for x >= 0.10 the appearance of a
metallic cluster glass phase, that develops just below the ferromagnetic
transition temperature. The clusters grow with decreasing temperature down to a
temperature T(f0) at which they freeze due to severe intercluster frustration.
The formation of these clusters is explained by the presence of yttrium induced
local structural distortions that create localized spin disorder in a magnetic
lattice where double-exchange ferromagnetism is dominant.

</DOC>
<DOC>
<DOCNO> 120831 </DOCNO>
Negative Vacuum Energy From Unrecaptured Matter


  Since the universe expansion is accelerating, it has been assumed that a
mysterious negative vacuum energy is the cause. There is a lack of more than
one peak on Boomerang and Maxima CBR analysis. These imply excess baryons,
which are difficult to reconcile with nucleosynthesis calculations. These and
other problems are solvable by having a hot and cold baryon bounce model. It
can simulate negative energy by having matter outside this universe from a
previous bounce. If the CBR planck spectrum is actually due to accretion
energy, early tidal forces will give a single peak on spectral analysis. Much
evidence is presented that supermassive galactic black holes originated in the
exploding shell of the big bang. A Biblical Genesis like model can solve the
hot big bang problems.

</DOC>
<DOC>
<DOCNO> 120172 </DOCNO>
Monte Carlo Simulations of Star Clusters


  A revision of Stod\'o{\l}kiewicz's Monte Carlo code is used to simulate
evolution of large star clusters. The survey on the evolution of multi-mass
N-body systems influenced by the tidal field of a parent galaxy and by stellar
evolution is discussed. For the first time, the simulation on the
"star-by-star" bases of evolution of 1,000,000 body star cluster is presented.
\

</DOC>
<DOC>
<DOCNO> 9025 </DOCNO>
Calculation of Second Topological Moment <m^2> of Two Entangled Polymers


  We set up a Chern-Simons theory for the entanglement of two polymers P_1 and
P_2, and calculate the second topological moment <m^2>, where m is the
linking number. The result applies approximately to a polymer in an ensemble of
many others, if these are considered as a single very long effective polymer.

</DOC>
<DOC>
<DOCNO> 71572 </DOCNO>
Domain wall fermions and applications


  Domain wall fermions provide a complimentary alternative to traditional
lattice fermion approaches. By introducing an extra dimension, the amount of
chiral symmetry present in the lattice theory can be controlled in a linear
way. This results in improved chiral properties as well as robust topological
zero modes. A brief introduction on the subject and a discussion of chiral
properties and applications, such as zero and finite temperature QCD, N = 1
super Yang-Mills, and four-fermion theories, is presented.

</DOC>
<DOC>
<DOCNO> 119458 </DOCNO>
The Palomar Abell Cluster Optical Survey I: Photometric Redshifts for


  This paper presents photometric redshifts for 431 Abell clusters imaged as
part of the Palomar Abell Cluster Optical Survey (PACOS), of which 236 are new
redshi fts. We have obtained moderately deep, 3--band (Gunn gri) imaging for
this sam ple at the Palomar Observatory 60'' telescope, as part of the
photometric calibration of DPOSS. Our data acquisition, reduction, and
photometric calibration techniques are described, and photometric accuracy and
consistency is demonstrated. An empirical redshift estimator is presented,
utilizing background-corrected median g-r colors and mean g magnitudes for the
ensemble of galaxies in each field. We present photometric redshift estimates
for the clusters in our sample with an accuracy of sigma_z=0.038. These
redshift estimates provide checks on single-galaxy cluster redshifts, as well
as distance information for studies of the Butcher-Oemler effect, luminosity
functions, M/L ratios, and many other projects.

</DOC>
<DOC>
<DOCNO> 170308 </DOCNO>
Renormalization and Short Distance Singular Structure


  The relation between renormalization and short distance singular divergencies
in quantum field theory is studied. As a consequence a finite theory is
presented. It is shown that these divergencies are originated by the
multiplication of distributions (and worse defined mathematical objects). Some
of them are eliminated defining a multiplication based in dimensional
regularization while others disappear considering the states as functionals
over the observables space. Non renormalizable theories turn to be finite, but
anyhow they are endowed with infinite arbitrary constants.

</DOC>
<DOC>
<DOCNO> 123223 </DOCNO>
The 2dF Galaxy Redshift Survey: Near Infrared Galaxy Luminosity


  We combine the 2MASS extended source catalogue and the 2dFGRS to produce an
IR selected galaxy catalogue with 17,173 measured redshifts. We use this
extensive dataset to estimate the J and K-band galaxy luminosity functions. The
LFs are fairly well fit by Schechter functions with J: M*-5log h=
-22.36+/-0.02, alpha= -0.93+/-0.04, Phi=0.0104+/-0.0016 h^3/Mpc^3 and K:
M*-5log h= -23.44+/-0.03, alpha=-0.96+/-0.05, Phi=0.0108+/-0.0016 h^3/Mpc^3
(2MASS Kron magnitudes). These parameters assume a cosmological model with
Omega=0.3 and Lambda=0.7. With datasets of this size, systematic rather than
random errors are the dominant source of uncertainty in the determination of
the LF. We carry out a careful investigation of possible systematic effects in
our data. The surface brightness distribution of the sample shows no evidence
that significant numbers of low surface brightness or compact galaxies are
missed by the survey. We estimate the present-day distributions of B-K and J-K
colours as a function of absolute magnitude and use models of the galaxy
stellar populations, constrained by the observed optical and infrared colours,
to infer the galaxy stellar mass function. Integrated over all galaxy masses,
this yields a total mass fraction in stars (in units of the critical mass
density) of Omega_*.h= (1.6+/-0.24)/10^3 for a Kennicutt IMF and Omega_*.h=
(2.9+/-0.43)/10^3 for a Salpeter IMF. These values agree with those inferred
from observational estimates of the star formation history of the universe
provided that dust extinction corrections are modest.

</DOC>
<DOC>
<DOCNO> 152529 </DOCNO>
Black holes on thick branes


  The interplay between topological defects (branes) and black holes has been a
subject of recent study, motivated in part by interest in brane-world
scenarios. In this paper we analyze in detail the description of a black hole
bound to a domain wall (a two-brane in four dimensions), for which an exact
description in the limit of zero wall thickness has been given recently. We
show how to smooth this singular solution with a thick domain wall. We also
show that charged extremal black holes of a size (roughly) smaller than the
brane thickness expel the wall, thereby extending the phenomenon of flux
expulsion. Finally, we analyze the process of black hole nucleation {\it on} a
domain wall, and argue that it is preferred over a previously studied mechanism
of black hole nucleation {\it away} from the wall.

</DOC>
<DOC>
<DOCNO> 85059 </DOCNO>
The Topological Origin of Black Hole Entropy


  In gravitational thermodynamics, the origin of a black hole's entropy is the
topology of its instanton or constrained instanton. We prove that the entropy
of an arbitrary nonrotating black hole is one quarter the sum of the products
of the Euler characteristics of its horizons with their respective areas. The
Gauss-Bonnet-like form of the action is not only crucial for the evaluation,
but also for the existence of the entropy. This result covers all previous
results on the entropy of a nonrotating black hole with a regular instanton.
The argument can be readily extended into the lower or higher dimensional
model. The problem of quantum creation of such a black hole is completely
resolved.

</DOC>
<DOC>
<DOCNO> 68612 </DOCNO>
Contact interaction probes at the Linear Collider with polarized


  For contact-interaction searches at the Linear Collider, we discuss the
advantages of polarizing both the electron and the positron beams as compared
with polarizing only the electron beam. In particular, for the processes
e^+e^-\to \mu^+\mu^-, \tau^+\tau^-, b\bar{b} and c\bar{c} at a future e^+e^-
collider with \sqrt{s}=0.5 TeV we derive model-independent bounds on the
four-fermion contact interaction parameters from studies of the helicity cross
sections.

</DOC>
<DOC>
<DOCNO> 69599 </DOCNO>
Soft gluon resummation for shape variable distributions in DIS


  We discuss the procedure to resum large logarithms to all orders for DIS
event shape variable distributions.
 Results are described for two variants of the thrust variable, both defined
wrt the boson axis in the current hemisphere of the Breit frame, but with
different normalisations.

</DOC>
<DOC>
<DOCNO> 169888 </DOCNO>
Quantum Codes for Controlling Coherent Evolution


  Control over spin dynamics has been obtained in NMR via coherent averaging,
which is implemented through a sequence of RF pulses, and via quantum codes
which can protect against incoherent evolution. Here, we discuss the design and
implementation of quantum codes to protect against coherent evolution. A
detailed example is given of a quantum code for protecting two data qubits from
evolution under a weak coupling (Ising) term in the Hamiltonian, using an
``isolated'' ancilla which does not evolve on the experimental time scale. The
code is realized in a three-spin system by liquid-state NMR spectroscopy on
13C-labelled alanine, and tested for two initial states. It is also shown that
for coherent evolution and isolated ancillae, codes exist that do not require
the ancillae to initially be in a (pseudo-)pure state. Finally, it is shown
that even with non-isolated ancillae quantum codes exist which can protect
against evolution under weak coupling. An example is presented for a six qubit
code that protects two data spins to first order.

</DOC>
<DOC>
<DOCNO> 118208 </DOCNO>
Multi-frequency VLBI observations of faint gigahertz peaked spectrum


  We present the data and analysis of VLBI observations at 1.6, 5 and 15 GHz of
a sample of faint Gigahertz Peaked Spectrum (GPS) sources selected from the
Westerbork Northern Sky Survey (WENSS). The 5 GHz observations involved a
global array of 16 stations and yielded data on the total sample of 47 sources.
A subsample of 26 GPS sources with peak frequencies > 5 GHz and/or peak flux
densities > 125 mJy was observed with the VLBA at 15 GHz. A second subsample of
29 sources, with peak frequencies <5 GHz, was observed at 1.6 GHz using a 14
station global VLBI array. In this way, 44 of the 47 sources (94%) in the
sample were observed above and at or below their spectral peak. Spectral
decomposition allowed us to identify 3, 11, 7, and 2 objects as compact
symmetric objects, compact doubles, core-jet and complex sources respectively.
 However, many of the sources classified as compact double or core-jet sources
show only two components making their classification rather tentative. This may
explain why the strong morphological dichotomy of GPS quasars and galaxies
found for radio-bright GPS sources, is not as clear in this faint sample.

</DOC>
<DOC>
<DOCNO> 13927 </DOCNO>
Thermodynamic Limit for Dipolar Media


  We prove existence of a shape and boundary condition independent
thermodynamic limit for fluids and solids of identical particles with electric
or magnetic dipole moments. Our result applies to fluids of hard core
particles, to dipolar soft spheres and Stockmayer fluids, to disordered solid
composites, and to regular crystal lattices. In addition to their permanent
dipole moments, particles may further polarize each other. Classical and
quantum models are treated. Shape independence depends on the reduction in free
energy accomplished by domain formation, so our proof applies only in the case
of zero applied field. Existence of a thermodynamic limit implies texture
formation in spontaneously magnetized liquids and disordered solids analogous
to domain formation in crystalline solids.

</DOC>
<DOC>
<DOCNO> 13155 </DOCNO>
Strong Coupling Fixed Points of Current Interactions and Disordered


  The all-orders beta function is used to study disordered Dirac fermions in
2D. The generic strong coupling fixed `points' of anisotropic current-current
interactions at large distances are actually isotropic manifolds corresponding
to subalgebras of the maximal current algebra at short distances. The IR
theories are argued to be current algebra cosets. We illustrate this with the
simple example of anisotropic su(2), which is the physics of
Kosterlitz-Thouless transitions. We work out the phase diagram for the
Chalker-Coddington network model which is in the universality class of the
integer Quantum Hall transition. One massless phase is in the universality
class of dense polymers.

</DOC>
<DOC>
<DOCNO> 69390 </DOCNO>
Possible formulations for three-charged particles correlations in terms


  The recent data for Bose-Einstein Correlations (BEC) of three-charged
particles obtained by NA44 Collaboration have been analysed using theoretical
formula with Coulomb wave functions. It has been recently proposed by Alt et
al. It turns out that there are discrepancies between these data and the
respective theoretical values. To resolve this problem we seek a possibly
modified theoretical formulation of this problem by introducing the degree of
coherence for the exchange effect due to the BEC between two-identical bosons.
As a result we obtain a modified formulation for the BEC of three-charged
particles showing good agreement with the data. Moreover, we investigate
physical connection between our modified formulation and the core-halo model
proposed by Csorgo et al. Our study indicates that the interaction region
estimated by the BEC of three-charged particles in the S + Pb collisions at 200
GeV/c per nucleon is equal to about 1.5 fm~1.8 fm.

</DOC>
<DOC>
<DOCNO> 117186 </DOCNO>
Progress in Induction Linacs


  This presentation will be a broad survey of progress in induction technology
over the past four years. Much work has been done on accelerators for
hydrodynamic test radiography and other applications. Solid-state pulsers have
been developed which can provide unprecedented flexibility and precision in
pulse format and accelerating voltage for both ion and electron induction
machines. Induction linacs can now be built which can operate with MHz
repetition rates. Solid-state technology has also made possible the development
of fast kickers for precision control of high current beams. New insulator
technology has been developed which will improve conventional induction linacs
in addition to enabling a new class of high gradient induction linacs.

</DOC>
<DOC>
<DOCNO> 67907 </DOCNO>
The static QCD potential in coordinate space with quark masses through


  The potential between infinitely heavy quarks in a color singlet state is of
fundamental importance in QCD. While the confining long distance part is
inherently non-perturbative, the short-distance (Coulomb-like) regime is
accessible through perturbative means. In this paper we present new results of
the short distance potential in coordinate space with quark masses through two
loops. The results are given in explicit form based on reconstructed solutions
in momentum space in the Euclidean regime. Thus, a comparison with lattice
results in the overlap region between the perturbative and non-perturbative
regime is now possible with massive quarks. We also discuss the definition of
the strong coupling based on the force between the static sources.

</DOC>
<DOC>
<DOCNO> 68857 </DOCNO>
New CMB constraints on the cosmic matter budget: trouble for


  We compute the joint constraints on ten cosmological parameters from the
latest CMB measurements. The lack of a significant second acoustic peak in the
latest Boomerang and Maxima data favors models with more baryons than Big Bang
nucleosynthesis predicts, almost independently of what prior information is
included. The simplest flat inflation models with purely scalar scale-invariant
fluctuations prefer a baryon density 0.022 <h^2 Omega_b < 0.040 and a total
nonbaryonic (hot + cold) dark matter density 0.14 < h^2 Omega_dm < 0.32 at 95%
confidence, and allow reionization no earlier than z~30.

</DOC>
<DOC>
<DOCNO> 69253 </DOCNO>
Next-to-Leading Order SUSY-QCD Predictions for Associated Production of


  We present complete results of a next-to-leading order calculation of the
production of gaugino-like charginos ($\chargino$) and neutralinos
($\neutralino$) in association with gluinos ($\gluino$) at hadron colliders,
including the strong corrections from the exchange of colored particles and
sparticles. Adopting a variety of models for the sparticle mass spectrum,
including typical supergravity (SUGRA) models and a light gluino model, we
provide predictions for total and differential cross sections at the energies
of the Fermilab Tevatron and CERN Large Hadron Collider (LHC).

</DOC>
<DOC>
<DOCNO> 121807 </DOCNO>
Helium white dwarf in PSR J0751+1807; too cool, in PSR J1012+5307; too


  We discuss the cooling history of the low-mass, helium core white dwarfs in
short orbital period millisecond pulsars PSR J0751+1807 and PSR J1012+5307. The
revised cooling age estimated by Alberts et al. agrees with the age estimation
for PSR J1012+5307, removing the discrepancy between the spin-down age and the
cooling age. However, if we accept this model then the helium white dwarf in
the binary pulsar system PSR J0751+1807 must be much hotter than is observed.
We propose that this discrepancy may be resolved if, after detachment of the
secondary star from its Roche lobe in PSR J0751+1807, the star loses its
hydrogen envelope due to pulsar irradiation. When hydrogen burning stops, the
white dwarf will cool down much more quickly than in the case of a thick
hydrogen envelope with a hydrogen burning shell. We discuss several
possibilities to explain different cooling histories of white dwarfs in both
systems.

</DOC>
<DOC>
<DOCNO> 13936 </DOCNO>
Criticality in polar fluids


  A model of polar fluid is studied theoretically. The interaction potential,
in addition to dipole-dipole term, possesses a dispersion contribution of the
van der Waals-London form. It is found that when the dispersion force is
comparable to dipole-dipole interaction, the fluid separates into coexisting
liquid and gas phases. The calculated critical parameters are in excellent
agreement with Monte Carlo simulations. When the strength of dispersion
attraction is bellow critical, no phase separation is found.

</DOC>
<DOC>
<DOCNO> 119249 </DOCNO>
Intrinsic and Extrinsic Galaxy Alignment


  We show with analytic models that the assumption of uncorrelated intrinsic
ellipticities of target sources that is usually made in searches for weak
gravitational lensing due to large-scale mass inhomogeneities (``field
lensing'') is unwarranted. If the orientation of the galaxy image is determined
either by the angular momentum or the shape of the halo in which it forms, then
the image should be aligned preferentially with the component of the tidal
gravitational field perpendicular to the line of sight. Long-range correlations
in the tidal field will thus lead to long-range ellipticity-ellipticity
correlations that mimic the shear correlations due to weak gravitational
lensing. We calculate the ellipticity-ellipticity correlation expected if halo
shapes determine the observed galaxy shape, and we discuss uncertainties (which
are still considerable) in the predicted amplitude of this correlation. The
ellipticity-ellipticity correlation induced by angular momenta should be
smaller. We consider several methods for discriminating between the
weak-lensing (extrinsic) and intrinsic correlations, including the use of
redshift information. An ellipticity--tidal-field correlation also implies the
existence of an alignment of images of galaxies near clusters. Although the
intrinsic alignment may complicate the interpretation of field-lensing results,
it is inherently interesting as it may shed light on galaxy formation as well
as on structure formation.

</DOC>
<DOC>
<DOCNO> 123273 </DOCNO>
Diffuse Gas and LMXBs in the Chandra Observation of the S0 Galaxy NGC


  We have spatially and spectrally resolved the sources of X-ray emission from
the X-ray faint S0 galaxy NGC 1553 using an observation from the Chandra X-ray
Observatory. The majority (70%) of the emission in the 0.3 - 10.0 keV band is
diffuse, and the remaining 30% is resolved into 49 discrete sources. Most of
the discrete sources associated with the galaxy appear to be low mass X-ray
binaries (LMXBs). The luminosity function of the LMXB sources is well-fit by a
broken power-law with a break luminosity comparable to the Eddington luminosity
for a 1.4 solar mass neutron star. It is likely that those sources with
luminosities above the break are accreting black holes and those below are
mostly neutron stars in binary systems. Spectra were extracted for the total
emission, diffuse emission, and sum of the resolved sources; the spectral fits
for all require a model including both a soft and hard component. The diffuse
emission is predominately soft while the emission from the sources is mostly
hard. Approximately 24% of the diffuse emission arises from unresolved LMXBs,
with the remainder resulting from thermal emission from hot gas. There is a
very bright source at the projected position of the nucleus of the galaxy. The
spectrum and luminosity derived from this central source are consistent with it
being an AGN; the galaxy also is a weak radio source. Finally, the diffuse
emission exhibits significant substructure with an intriguing spiral feature
passing through the center of the galaxy. The X-ray spectrum and surface
brightness of the spiral feature are consistent with adiabatic or shock
compression of ambient gas, but not with cooling. This feature may be due to
compression of the hot interstellar gas by radio lobes or jets associated with
the AGN.

</DOC>
<DOC>
<DOCNO> 68385 </DOCNO>
Top Quark Physics


  We review the prospects for studies of the top quark at the LHC.

</DOC>
<DOC>
<DOCNO> 12569 </DOCNO>
Bridge Hopping on Conducting Polymers in Solution


  Configurational fluctuations of conducting polymers in solution can bring
into proximity monomers which are distant from each other along the backbone.
Electrons can hop between these monomers across the "bridges" so formed. We
show how this can lead to (i) a collapse transition for metallic polymers, and
(ii) to the observed dramatic efficiency of acceptor molecules for quenching
fluorescence in semiconducting polymers.

</DOC>
<DOC>
<DOCNO> 120643 </DOCNO>
Comptonization in the accretion column of the X-ray pulsar GX~1+4


  X-ray observations of the binary pulsar GX 1+4 made using the Rossi X-ray
Timing Explorer (RXTE) satellite between February 1996 and May 1997 were
analysed to quantify source spectral variation with luminosity.
  Mean Proportional Counter Array (PCA) spectra over the range 2-40 keV are
best fitted with a Comptonization model, with source spectrum temperature T_0
approx 1-1.3 keV, plasma temperature T_e approx 6-10 keV, and optical depth tau
approx 2-6. The range of fitted T_0 was consistent with the source spectrum
originating at the neutron star polar cap, with Compton scattering taking place
primarily in the hot plasma of the accretion column. Both the fitted optical
depth and plasma temperature vary significantly with the source flux. The
variation of the optical depth (and hence the density of the scattering region)
with luminosity strongly suggests increasing cross-sectional area of the
accretion column at higher accretion rate Mdot.
  The wide range of source luminosity spanned by archival observations of GX
1+4 offers evidence for two distinct spectral states above and below L_X approx
2*10^{37} erg/s (2-60 keV, assuming a source distance of 10 kpc). GX 1+4
additionally exhibits dramatic hourly variations in neutral column density n_H
indicative of density variations in the stellar wind from the giant companion.

</DOC>
<DOC>
<DOCNO> 10420 </DOCNO>
Dynamical Quasi-Stationary States in a system with long-range forces


  The Hamiltonian Mean Field model describes a system of N fully-coupled
particles showing a second-order phase transition as a function of the energy.
The dynamics of the model presents interesting features in a small energy
region below the critical point. In particular, when the particles are prepared
in a ``water bag'' initial state, the relaxation to equilibrium is very slow.
In the transient time the system lives in a dynamical quasi-stationary state
and exhibits anomalous (enhanced) diffusion and L\'evy walks. In this paper we
study temperature and velocity distribution of the quasi-stationary state and
we show that the lifetime of such a state increases with N. In particular when
the $N\to \infty$ limit is taken before the $t \to \infty$ limit, the results
obtained are different from the expected canonical predictions. This scenario
seems to confirm a recent conjecture proposed by C.Tsallis.

</DOC>
<DOC>
<DOCNO> 120318 </DOCNO>
Compact star clusters of the LMC HII region N11C


  Based on imaging and spectroscopy obtained at the ESO NTT telescope and using
an efficient image analysis algorithm, we study the core of the LMC OB
association LH13, particularly the two compact stellar clusters Sk-6641 and HNT
in the HII, region N11C. We resolve Sk-6641 into 15 components and for the
first time the HNT cluster into 70 stars, and derive photometry for the
members. Moreover, from medium resolution spectroscopy we determine the
spectral types for sixteen stars in N11C. We compare the color-magnitude
diagrams of the clusters with that of the field stars and discuss the cluster
ages. With an age of ~100 Myr, the HNT cluster appears significantly older than
the very young (< 5 Myr) Sk-6641 starburst. We suggest that most of the `field'
O-stars in the core of N11C have actually been ejected from Sk-6641 through
dynamical interactions in the compact cluster. The properties of the Sk-6641
and HNT clusters suggest that we are viewing different star formation regions
lying at different distances along the same line of sight.

</DOC>
<DOC>
<DOCNO> 85104 </DOCNO>
A crucial ingredient of inflation


  Nonminimal coupling of the inflaton field to the Ricci curvature of spacetime
is generally unavoidable, and the paradigm of inflation should be generalized
by including the corresponding term in the Lagrangian of the inflationary
theory. This paper reports on the status of the programme of generalizing
inflation. First, the problem of finding the correct value (or set of values)
of the coupling constant is analyzed; the result has important consequences for
the success or failure of inflationary scenarios. Then, the slow-roll
approximation to generalized inflation is studied. Both the unperturbed
inflating universe models and scalar/tensor perturbations are discussed, and
open problems are pointed out.

</DOC>
<DOC>
<DOCNO> 123050 </DOCNO>
Low-latitude gamma-ray sources: correlations and variability


  A review of the main characteristics of low-latitude sources in the third
EGRET catalog is presented. There are 75 unidentified gamma-ray sources
detected by EGRET at less than 10 degrees from the galactic plane. About a half
of these sources are spatially correlated with potential galactic gamma-ray
emitters such as supernova remnants, OB associations and early-type stars with
very strong stellar winds. The other half is formed by sources without
positional correlation with known galactic objects capable to generate a gamma
ray flux significant enough as to be detected by EGRET. A variability analysis
shows that this second group of sources contains several objects with high
levels of gamma-ray variability. These variable sources resemble very much the
AGNs detected by EGRET, but without their typical strong radio emission. To
establish the nature of these sources is one of the most urgent problems of
high-energy astrophysics.

</DOC>
<DOC>
<DOCNO> 71025 </DOCNO>
Two-loop corrections to the topological mass term in thermal QED_3


  We study the radiative corrections to the Chern-Simons mass term at two loops
in 2+1 dimensional quantum electrodynamics at finite temperature. We show that,
in contrast to the behavior at zero temperature, thermal effects lead to a non
vanishing contribution at this order. Using this result, as well as the large
gauge Ward identity for the leading parity violating terms in the static limit,
we determine the leading order parity violating effective action in this limit
at two loops, which generalizes the one-loop effective action proposed earlier.

</DOC>
<DOC>
<DOCNO> 151678 </DOCNO>
Action, Hamiltonian and CFT for 2D black holes


  The boundary terms in the Hamiltonian, in the presence of horizons, are
carefully analyzed in a simple 2D theory admitting AdS black holes. The
agreement between the euclidean approach and Cardy's formula is obtained modulo
certain assumptions on the spectrum of the Virasoro's algebra. There is no
discrepancy factor "square root of 2" once the appropriate boundary conditions
are properly recognized. The peculiar features of gravity, that the on-shell
Hamiltonian is determined by boundary terms, is the reason of the mentioned
agreement.

</DOC>
<DOC>
<DOCNO> 71788 </DOCNO>
On importance of dark matter for LHC physics


  I would like to attract attention of the LHC high-energy physics community to
non-accelerator, low-energy experiments, that are also very sensitive to new
physics. My example concerns search for supersymmetric dark matter particles.
It is shown that non-observation of the SUSY dark matter candidates with a
high-accuracy detector can exclude large domains of the MSSM parameter space
and, in particular, can make especially desirable collider search for light
SUSY charged Higgs boson.

</DOC>
<DOC>
<DOCNO> 174477 </DOCNO>
Positron spectra from internal pair conversion observed in {238}U +


  We present new results from measurements and simulations of positron spectra,
originating from 238U + 181Ta collisions at beam energies close to the Coulomb
barrier. The measurements were performed using an improved experimental setup
at the double-Orange spectrometer of GSI. Particular emphasis is put on the
signature of positrons from Internal-Pair-Conversion (IPC) processes in the
measured e+ energy spectra, following the de-excitation of electromagnetic
transitions in the moving Ta-like nucleus. It is shown by Monte Carlo
simulations that, for the chosen current sweeping procedure used in the present
experiments, positron emission from discrete IPC transitions can lead to rather
narrow line structures in the measured energy spectra. The measured positron
spectra do not show evidence for line structures within the statistical
accuracy achieved, although expected from the intensities of the observed
$\gamma$ transitions (E$_{\gamma}~1250-1600$ keV) and theoretical conversion
coefficients. This is due to the reduced detection efficiency for IPC
positrons, caused by the limited spatial and momentum acceptance of the
spectrometer. A comparison with previous results, in which lines have been
observed, is presented and the implications are discussed.

</DOC>
<DOC>
<DOCNO> 8208 </DOCNO>
High Frequency EPR Spectra of [Fe8O2(OH)12(tacn)6]Br8. A Critical


  A detailed multifrequency high field - high frequency EPR (95-285 GHz) study
has been performed on the single-molecule magnet of formula
 [Fe8O2(OH)12(tacn)6]Br8 9H2O, where tacn=1,4,7-triazacyclononane.
Polycrystalline powder spectra have allowed estimating the zero field splitting
parameters up to the fourth order terms.
 The single crystal spectra have provided the principal directions of the
magnetic anisotropy of the cluster. These results have been compared to an
evaluation of the intra-cluster dipolar contribution to the magnetic
anisotropy, suggesting that single ion anisotropy is mainly contributing to the
magnetic anisotropy.
 The role of the transverse magnetic anisotropy in determining the height of
the barrier for the reversal of the magnetization is also discussed.

</DOC>
<DOC>
<DOCNO> 151238 </DOCNO>
Casimir Energy of a Semi-Circular Infinite Cylinder


  The Casimir energy of a semi-circular cylindrical shell is calculated by
making use of the zeta function technique. This shell is obtained by crossing
an infinite circular cylindrical shell by a plane passing through the symmetry
axes of the cylinder and by considering only a half of this configuration. All
the surfaces, including the cutting plane, are assumed to be perfectly
conducting. The zeta functions for scalar massless fields obeying the Dirichlet
and Neumann boundary conditions on the semi-circular cylinder are constructed
exactly. The sum of these zeta functions gives the zeta function for
electromagnetic field in question. The relevant plane problem is considered
also. In all the cases the final expressions for the corresponding Casimir
energies contain the pole contributions which are the consequence of the edges
or corners in the boundaries. This implies that further renormalization is
needed in order for the finite physical values for vacuum energy to be obtained
for given boundary conditions.

</DOC>
<DOC>
<DOCNO> 10080 </DOCNO>
Distribution of instanton sizes in a simplified instanton gas model


  We investigate the distribution of instanton sizes in the framework of a
simplified model for ensembles of instantons. This model takes into account the
non-diluteness of instantons. The infrared problem for the integration over
instanton sizes is dealt with in a self-consistent manner by approximating
instanton interactions by a repulsive hard core potential. This leads to a
dynamical suppression of large instantons. The characteristic features of the
instanton size distribution are studied by means of analytic and Monte Carlo
methods. In one dimension exact results can be derived. In any dimension we
find a power law behaviour for small sizes, consistent with the semi-classical
results. At large instanton sizes the distribution decays exponentially. The
results are compared with those from lattice simulations.

</DOC>
<DOC>
<DOCNO> 84623 </DOCNO>
Anholonomic Soliton-Dilaton and Black Hole Solutions in General


  A new method of construction of integral varieties of Einstein equations in
three dimensional (3D) and 4D gravity is presented whereby, under corresponding
redefinition of physical values with respect to anholonomic frames of reference
with associated nonlinear connections, the structure of gravity field equations
is substantially simplified. It is shown that there are 4D solutions of
Einstein equations which are constructed as nonlinear superpositions of soliton
solutions of 2D (pseudo) Euclidean sine-Gordon equations (or of Lorentzian
black holes in Jackiw-Teitelboim dilaton gravity). The Belinski-Zakharov-Meison
solitons for vacuum gravitational field equations are generalized to various
cases of two and three coordinate dependencies, local anisotropy and matter
sources. The general framework of this study is based on investigation of
anholonomic soliton-dilaton black hole structures in general relativity. We
prove that there are possible static and dynamical black hole, black torus and
disk/cylinder like solutions (of non-vacuum gravitational field equations) with
horizons being parametrized by hypersurface equations of rotation ellipsoid,
torus, cylinder and another type configurations. Solutions describing locally
anisotropic variants of the Schwarzschild-- Kerr (black hole), Weyl
(cylindrical symmetry) and Neugebauer--Meinel (disk) solutions with anisotropic
variable masses, distributions of matter and interaction constants are shown to
be contained in Einstein's gravity. It is demonstrated in which manner locally
anisotropic multi-soliton-- dilaton-black hole type solutions can be generated.

</DOC>
<DOC>
<DOCNO> 101251 </DOCNO>
Orthogonal divided differences and Schubert polynomials, \~P-functions,


  We give several new formulas which are useful for Schubert Calculus
associated with the orthogonal groups and related orthogonal degeneracy loci.

</DOC>
<DOC>
<DOCNO> 70631 </DOCNO>
New supersymmetric standard model with stable proton


  We discuss a supersymmetric extension of the standard model with an extra
U(1) gauge symmetry. In this model, the proton stability is guaranteed by the
gauge symmetry without invoking R parity. The gauge symmetry breakdown
automatically generates an effective $\mu$ term and large Majorana masses for
right-handed neutrinos. The supersymmetry-soft-breaking terms for scalar fields
could be universal at a very high energy scale, and the electroweak symmetry is
broken through radiative corrections.

</DOC>
<DOC>
<DOCNO> 11482 </DOCNO>
Universality of S-matrix correlations for deterministic plus random


  We study S-matrix correlations for random matrix ensembles with a Hamiltonian
which is the sum of a given deterministic part and of a random matrix with a
Gaussian probability distribution. Using Efetov's supersymmetry formalism, we
show that, in the limit of infinite matrix size of the Hamiltonian, correlation
functions of S-matrix elements are universal on the scale of the local mean
level spacing: the dependence of the deterministic part enters into these
correlation functions only through the average S-matrix and the average level
density. This statement applies to each of the three symmetry classes
(orthogonal, unitary, and symplectic).

</DOC>
<DOC>
<DOCNO> 119673 </DOCNO>
A Short History of the Missing Mass and Dark Energy Paradigms


  In 1900 it was believed that almost 100% of the mass of the Universe resided
in stars. Now, in the year 2000, such stars (and cold gas) are known to account
for only ~1% its mass. The remaining mass of the Universe is thought to reside
in hot baryons (~3%), cold dark matter (~30%) and dark energy (~66%). The
present paper traces the evolution of our thinking about the density of the
Universe during the Twentieth Century, with special emphasis on the of the
discovery of cold dark matter.

</DOC>
<DOC>
<DOCNO> 68603 </DOCNO>
Complete Two-loop Dominant Corrections to the Mass of the Lightest


  Using an effective potential approach, we compute two-loop radiative
corrections to the MSSM lightest ${\cal CP}$-even Higgs boson mass $M_{h^0}$ to
${\cal O}(\alpha_t^2)$ for arbitrary left-right top-squark mixing and
$\tan\beta$. We find that these corrections can increase $M_{h^0}$ by as much
as 5 GeV; assuming a SUSY scale of 1 TeV, the upper bound on the Higgs boson
mass is $M_{h^0}\approx 129\pm 5$ GeV for the top quark pole mass $175\pm 5$
GeV. We also derive an analytical approximation formula for $M_{h^0}$ which is
good to a precision of $\lsim 0.5$ GeV for most of the parameter space and
suitable to be further improved by including renormalization group resummation
of leading and next-to-leading order logarithmic terms. Our final compact
formula admits a clear physical interpretation: radiative corrections up to the
two-loop level can be well approximated by a one-loop expression with
parameters evaluated at the appropriate scales, plus a smaller finite two-loop
threshold correction term.

</DOC>
<DOC>
<DOCNO> 121581 </DOCNO>
Asphericity of galaxy clusters and Sunyaev-Zel'dovich effect


  In this paper we investigate the Sunyaev-Zel'dovich (SZ) effect and the X-ray
surface brightness for clusters of galaxies with a non-spherical mass
distribution. In particular, we consider the influence of the shape and the
finite extension of a cluster as well as of a polytropic thermal profile on the
Compton parameter, the X-ray surface brightness and on the determination of the
Hubble constant. We find that the the non-inclusion of such effects can induce
errors up to 30 per cent in the various parameters and in particular on the
Hubble constant value, when compared with results obtained under the
isothermal, infinitely extended and spherical shape assumptions.

</DOC>
<DOC>
<DOCNO> 85517 </DOCNO>
Algebraic integrability of FRW-scalar cosmologies


  For dynamical systems of dimension three or more the question of
integrability or nonintegrability is extended by the possibility of chaotic
behaviour in the general solution. We determine the integrability of isotropic
cosmological models in general relativity and string theory with a variety of
matter terms, by a performance of the Painlev\'{e} analysis in an effort to
examine whether or not there exists a Laurent expansion of the solution about a
movable pole which contains the number of arbitrary constants necessary for a
general solution.

</DOC>
<DOC>
<DOCNO> 7708 </DOCNO>
Quasiparticles and Phase Fluctuations in High Tc Superconductors


  We argue based on theoretical considerations and analysis of experimental
data that quasiparticle excitations near the nodes determine the low
temperature properties in the superconducting state of cuprates. Quantum
effects of phase fluctuations are shown to be quantitatively important, but
thermal effects are small for $T \ll T_c$. An anisotropic superfluid Fermi
liquid phenomenology is presented for the effect of quasiparticle interactions
on the temperature and doping dependence of the low $T$ penetration depth.

</DOC>
<DOC>
<DOCNO> 83099 </DOCNO>
Don't Trash your Intermediate Results, Cache 'em


  In data warehouse and data mart systems, queries often take a long time to
execute due to their complex nature. Query response times can be greatly
improved by caching final/intermediate results of previous queries, and using
them to answer later queries. In this paper we describe a caching system called
Exchequer which incorporates several novel features including optimization
aware cache maintenance and the use of a cache aware optimizer. In contrast, in
existing work, the module that makes cost-benefit decisions is part of the
cache manager and works independent of the optimizer which essentially
reconsiders these decisions while finding the best plan for a query. In our
work, the optimizer takes the decisions for the cache manager. Furthermore,
existing approaches are either restricted to cube (slice/point) queries, or
cache just the query results. On the other hand, our work is extens ible and in
fact presents a data-model independent framework and algorithm. Our
experimental results attest to the efficacy of our cache management techniques
and show that over a wide range of parameters (a) Exchequer's query response
times are lower by more than 30% compared to the best performing competitor,
and (b) Exchequer can deliver the same response time as its competitor with
just one tenth of the cache size.

</DOC>
<DOC>
<DOCNO> 170531 </DOCNO>
Quantum clock synchronization and quantum error correction


  I consider quantum protocols for clock synchronization, and investigate in
particular whether entanglement distillation or quantum error-correcting codes
can improve the robustness of these protocols. I also draw attention to some
unanswered questions about the relativistic theory of quantum measurement. This
paper is based on a talk given at the NASA-DoD Workshop on Quantum Information
and Clock Synchronization for Space Applications (QuICSSA), September 25-26,
2000.

</DOC>
<DOC>
<DOCNO> 10656 </DOCNO>
Nonlinear optical response and spin-charge separation in one-dimensional


  We theoretically study the nonlinear optical response and photoexcited states
of the Mott insulators. The nonlinear optical susceptibility \chi^(3) is
calculated by using the exact diagonalization technique on small clusters. From
the systematic study of the dependence of \chi^(3) on dimensionality, we find
that the spin-charge separation plays a crucial role in enhancing \chi^(3) in
the one-dimensional (1D) Mott insulators. Based on this result, we propose a
holon-doublon model, which describes the nonlinear response in the 1D Mott
insulators. These findings show that the spin-charge separation will become a
key concept of optoelectronic devices.

</DOC>
<DOC>
<DOCNO> 71366 </DOCNO>
Observation of a New J(PC)=1(+-) Isoscalar State in the Reaction Pi-


  Results are presented on a partial wave analysis of the Omega Eta final state
produced in Pi- Proton interactions at 18 GeVc where Omega -> Pi+ Pi- Pi0, Pi0
-> 2 Gammas, and Eta -> 2 Gammas. We observe the previously unreported decay
mode Omega(1650) -> Omega Eta and a new 1(+-) meson state h1(1595) with a mass
M=1594(15)(+10)(-60) MeV/c^2 and a width Gamma=384(60)(+70)(-100) MeV/c^2. The
h1(1595) state exhibits resonant-like phase motion relative to the Omega(1650).

</DOC>
<DOC>
<DOCNO> 84737 </DOCNO>
Plane Wave Limits and T-Duality


  The Penrose limit is generalized to show that, any leading order solution of
the low-energy field equations in any one of the five string theories has a
plane wave solution as a limit. This limiting procedure takes into account all
the massless fields that may arise and commutes with the T-duality so that any
dual solution has again a plane wave limit. The scaling rules used in the limit
are unique and stem from the scaling property of the D=11 supergravity action.
Although the leading order solutions need not be exact or supersymmetric, their
plane wave limits always preserve some portion of the Poincare supersymmetry
and solve the relevant field equations in all powers of the string tension
parameter. Further properties of the limiting procedure are discussed.

</DOC>
<DOC>
<DOCNO> 120341 </DOCNO>
Young Stellar Groups, Runaway Stars, and Pulsars


  Milli-arcsecond astrometry provided by Hipparcos and by radio observations
makes it possible to retrace the orbits of nearby runaway stars and pulsars
with sufficient accuracy to identify their parent stellar cluster or
association. For two cases it is even possible to deduce the specific formation
scenario. The runaway star zeta Oph and PSR J1932+1059 are the result of a
supernova explosion which took place 1 Myr ago in a massive binary in the Upper
Scorpius association. The pulsar received a kick velocity of about 350 km/s in
this event. The runaway stars mu Col and AE Aur and the isolated eccentric
massive binary iota Ori result from a binary-binary encounter, most likely
inside the Trapezium cluster, 2.5 Myr ago. Future astrometric missions such as
DIVA, FAME and in particular GAIA will allow extension of these studies to a
significant fraction of the Galactic disk, and will provide new constraints on
the formation and evolution of massive stars.

</DOC>
<DOC>
<DOCNO> 68486 </DOCNO>
Gluon Fragmentation into Glueballs and Hybrid Mesons


  The constituent nature of candidate gluonic mesons can be studied by
comparing their production in quark and gluon jets. The production rate for
such mesons depends on the colour confinement processes at the end of the
perturbative evolution. Whereas we expect enhanced production of hybrids in the
fragmentation region of a gluon jet, the rate for glueballs depends on the
relative importance of colour triplet and colour octet neutralization. These
neutralization processes can be studied independently in events with large
rapidity gaps. If octet processes turn out important the recently suggested
lightest J^{PC}=0^{++} glueball with mass around 1000 MeV should become visible
already in the spectrum of the leading charged particle pairs.

</DOC>
<DOC>
<DOCNO> 122880 </DOCNO>
The Properties of High Redshift Galaxies


  In recent years, a variety of techniques at optical, near-infrared, sub-mm,
and radio wavelengths have opened complementary windows on the high-redshift
Universe. Here we review the current understanding of the general properties of
the z>~2 galaxies detected in the optical (Lyman-break galaxies) and in the
sub-mm (SCUBA sources). We list some of the key questions that need to be
answered in order to understand the nature and evolution of the high-redshift
galaxies. Wherever possible, we present tentative answers given so far to those
questions, in particular on the low-redshift couterparts of the high-redshift
galaxies, on the impact of dust obscuration on the observed quantities, and on
physical characteristics of the high-z systems as inferred from observations.

</DOC>
<DOC>
<DOCNO> 99781 </DOCNO>
Multipartitions, Generalized Durfee Squares and Affine Lie Algebra


  We give some higher dimensional analogues of the Durfee square formula and
point out their relation to dissections of multipartitions. We apply the
results to write certain affine Lie algebra characters in terms of Universal
Chiral Partition Functions.

</DOC>
<DOC>
<DOCNO> 116446 </DOCNO>
Ultrahigh sensitivity of slow-light gyroscope


  Slow light generated by Electromagnetically Induced Transparency is extremely
susceptible with respect to Doppler detuning. Consequently, slow-light
gyroscopes should have ultrahigh sensitivity.

</DOC>
<DOC>
<DOCNO> 8552 </DOCNO>
Asymptotic form of two-point correlation function of the XXZ spin chain


  Correlation functions of the XXZ spin chain in the critical regime is studied
at zero-temperature. They are exactly represented in the Fredholm determinant
form and are related with an operator-valued Riemann-Hilbert problem. Analyzing
this problem we prove that a two-point correlation function consisting of
sufficiently separated spin operators is expressed by power-functions of the
distance between those operators.

</DOC>
<DOC>
<DOCNO> 122973 </DOCNO>
Structure of the X-ray Emission from the Jet of 3C 273


  We present images from five observations of the quasar 3C 273 with the
Chandra X-ray Observatory. The jet has at least four distinct features which
are not resolved in previous observations. The first knot in the jet (A1) is
very bright in X-rays. Its X-ray spectrum is well fitted with a power law with
alpha = 0.60 +/- 0.05. Combining this measurement with lower frequency data
shows that a pure synchrotron model can fit the spectrum of this knot from
1.647 GHz to 5 keV (over nine decades in energy) with alpha = 0.76 +/- 0.02,
similar to the X-ray spectral slope. Thus, we place a lower limit on the total
power radiated by this knot of 1.5e43 erg/s; substantially more power may be
emitted in the hard X-ray and gamma-ray bands.
  Knot A2 is also detected and is somewhat blended with knot B1. Synchrotron
emission may also explain the X-ray emission but a spectral bend is required
near the optical band. For knots A1 and B1, the X-ray flux dominates the
emitted energy. For the remaining optical knots (C through H), localized X-ray
enhancements that might correspond to the optical features are not clearly
resolved. The position angle of the jet ridge line follows the optical shape
with distinct, aperiodic excursions of +/-1 deg from a median value of
-138.0deg. Finally, we find X-ray emission from the ``inner jet'' between 5 and
10" from the core.

</DOC>
<DOC>
<DOCNO> 12632 </DOCNO>
Realistic spin glasses below eight dimensions: a highly disordered view


  By connecting realistic spin glass models at low temperature to the highly
disordered model at zero temperature, we argue that ordinary Edwards-Anderson
spin glasses below eight dimensions have at most a single pair of physically
relevant pure states at nonzero low temperature. Less likely scenarios that
evade this conclusion are also discussed.

</DOC>
<DOC>
<DOCNO> 11371 </DOCNO>
Statistics of lattice animals (polyominoes) and polygons


  We have developed an improved algorithm that allows us to enumerate the
number of site animals (polyominoes) on the square lattice up to size 46.
Analysis of the resulting series yields an improved estimate, $\tau =
4.062570(8)$, for the growth constant of lattice animals and confirms to a very
high degree of certainty that the generating function has a logarithmic
divergence. We prove the bound $\tau > 3.90318.$ We also calculate the radius
of gyration of both lattice animals and polygons enumerated by area. The
analysis of the radius of gyration series yields the estimate $\nu =
0.64115(5)$, for both animals and polygons enumerated by area. The mean
perimeter of polygons of area $n$ is also calculated. A number of new amplitude
estimates are given.

</DOC>
<DOC>
<DOCNO> 80695 </DOCNO>
Center-vortex dominance after dimensional reduction of SU(2) lattice


  The high-temperature phase of SU(2) Yang-Mills theory is addressed by means
of dimensional reduction with a special emphasis on the properties of center
vortices. For this purpose, the vortex vacuum which arises from center
projection is studied in pure 3-dimensional Yang-Mills theory as well as in the
3-dimensional adjoint Higgs model which describes the high temperature phase of
the 4-dimensional SU(2) gauge theory. We find center-dominance within the
numerical accuracy of 10%.

</DOC>
<DOC>
<DOCNO> 67862 </DOCNO>
An Early Proposal of "Brane World"


  Here we place the TeX-typeset version of the old preprint SMC-PHYS-66 (1982),
which was published in K. Akama, "Pregeometry", in Lecture Notes in Physics,
176, Gauge Theory and Gravitation, Proceedings, Nara, 1982, edited by K.
Kikkawa, N. Nakanishi and H. Nariai, (Springer-Verlag) 267--271. In the paper,
we presented the picture that we live in a "brane world" (in the present-day
terminology) i.e. in a dynamically localized 3-brane in a higher dimensional
space. We adopt, as an example, the dynamics of the Nielsen-Olesen vortex type
in six dimensional spacetime to localize our space-time within a 3-brane. At
low energies, everything is trapped in the 3-brane, and the Einstein gravity is
induced through the fluctuations of the 3-brane. The idea is important because
it provides a way basically distinct from the "compactification" to hide the
extra dimensions which become necessary for various theoretical reasons.

</DOC>
<DOC>
<DOCNO> 40649 </DOCNO>
Experimental Issues for Precision Electroweak Physics at a


  We discuss the ultimate precision for ALR, and therefore for the weak mixing
angle, at a high-luminosity Linear Collider. Drawing on our experience at the
SLC, and considering various machine parameter sets for the NLC and for TESLA,
it emerges that a compromise between peak luminosity and precision will be a
likely outcome. This arises due to the severe requirements on the uncertainty
in the luminosity weighted collision energy (Ecm). We consider the cases with
and without a polarized positron beam.

</DOC>
<DOC>
<DOCNO> 118808 </DOCNO>
An efficient algorithm for two-dimensional radiative transfer in


  We present an algorithm for two-dimensional radiative transfer in
axisymmetric, circumstellar media. The formal integration of the transfer
equation is performed by a generalization of the short characteristics (SC)
method to spherical coordinates. Accelerated Lambda Iteration (ALI) and Ng's
algorithm are used to converge towards a solution. By taking a logarithmically
spaced radial coordinate grid, the method has the natural capability of
treating problems that span several decades in radius, in the most extreme case
from the stellar radius up to parsec scale. Flux conservation is guaranteed in
spherical coordinates by a particular choice of discrete photon directions and
a special treatment of nearly-radially outward propagating radiation. The
algorithm works well from zero up to very high optical depth, and can be used
for a wide variety of transfer problems, including non-LTE line formation, dust
continuum transfer and high temperature processes such as compton scattering.
In this paper we focus on multiple scattering off dust grains and on non-LTE
transfer in molecular and atomic lines. Line transfer is treated according to
an ALI scheme for multi-level atoms/molecules, and includes both random and
systematic velocity fields. The algorithms are implemented in a multi-purpose
user-friendly radiative transfer program named RADICAL. We present two example
computations: one of dust scattering in the Egg Nebula, and one of non-LTE line
formation in rotational transitions of HCO$^{+}$ in a flattened protostellar
collapsing cloud.

</DOC>
<DOC>
<DOCNO> 178989 </DOCNO>
Isoscalar Giant Dipole Resonance and Nuclear Matter Incompressibility


  We present results of microscopic calculations of the strength function,
S(E), and alpha-particle excitation cross sections sigma(E) for the isoscalar
giant dipole resonance (ISGDR). An accurate and a general method to eliminate
the contributions of spurious state mixing is presented and used in the
calculations. Our results provide a resolution to the long standing problem
that the nuclear matter incompressibility coefficient, K, deduced from sigma(E)
data for the ISGDR is significantly smaller than that deduced from data for the
isoscalar giant monopole resonance (ISGMR).

</DOC>
<DOC>
<DOCNO> 8723 </DOCNO>
Quasi-Spin-Charge Separation and the Spin Quantum Hall Effect


  We use quantum field theory methods to study the network model for the spin
quantum hall transition. When the couplings are fine tuned in a certain way,
the spin and charge degrees of freedom, corresponding to the supercurrent
algebras su(2) and osp(2|2) respectively, decouple in the renormalization group
flow. The infrared fixed point of this simpler theory is the coset
osp(4|4)/su(2) which is closely related to the current algebra osp(2|2) but not
identical. Some critical exponents are computed and shown to agree with the
recent predictions based on percolation.

</DOC>
<DOC>
<DOCNO> 68773 </DOCNO>
Dynamical gluon mass corrections in heavy quarkonia decays


  Using the expression of the dynamical gluon mass obtained through the
operator product expansion we discuss the relevance of gluon mass effects in
the decays V -> hadrons (V = J/Psi, Upsilon). Relativistic and radiative
corrections are also introduced to calculate alpha_s(m_c) and alpha_s(m_b)
comparing them with other values available in the literature. The effects of
dynamical gluon masses are negligible for Upsilon decay but important for J/Psi
decay.

</DOC>
<DOC>
<DOCNO> 70648 </DOCNO>
One-loop contributions of the super-partner particles to $e^-e^+ \to


  One-loop contributions of super-partner particles to $W$-pair production at
$e^+e^-$ collision are discussed in the MSSM. To obtain trustworthy results we
test our calculation using three methods: (1) sum rules among form factors
which result from the BRS invariance, (2) the decoupling theorem, (3) the
high-energy stability. We examine the corrections taking into account
constraints from the direct search experiments and the precision data. The
results for the sfermion contributions are presented.

</DOC>
<DOC>
<DOCNO> 120916 </DOCNO>
QSO 2359-1241: A Bright, Highly Polarized, Radio-Moderate, Reddened,


  We report the discovery of a bright quasar (E=15.8, z=0.868) associated with
the flat spectrum radio source NVSS J235953-124148. This quasar we designate
QSO 2359-1241 possesses a rare combination of extreme properties that make it
of special interest. These properties include: intrinsic high-velocity outflow
seen in absorption for both high and low-ionization species, high optical
polarization (about 5%), significant radio emission, and dust reddening. The
dereddened absolute magnitude of QSO 2359-1241 places it among the three most
optically luminous quasars known at z<1. High-resolution spectroscopy and a
detailed analysis of the optical/ultraviolet absorption features will be given
in a companion paper (Arav et al 2000).

</DOC>
<DOC>
<DOCNO> 116644 </DOCNO>
Do Gravitational and Electromagnetic Fields Have Rest Masses in the


  As well known rest masses of elementary particles and physical fields appear
when temperature of Universe become low enough and symmetry broke. Are there
another sources of rest masses that are consequences of other nature of rest
masses or it is the only methods for generating rest masses? What will be with
massless fields when the laws of symmetry are not exact laws but only are very
good approximation and the time is not homogeneous, as it is in the fractal
world? In this paper based on the fractal theory of time and space (developed
by author earlier) a possible source of rest masses caused by the fractional
dimensions (FD) of the time is considered. It gives rest masses (very small)
for all particles and fields including gravitational and electromagnetic
fields. The estimation of the values of the rest masses gives
$m_{g}=\sqrt{\epsilon (tt_{i})^{-1}}$, $m_{f}= \sqrt{(t_{0}t_{i})^{-1}}$ where
$t_{i}$ is the necessary time for photons and gravitons with rest masses
$m_{ph}$ and $m_{g}$ to get the velocity equal the speed of light (in the
fractal Universe the moving with any velocities is possible), $t_{0}$ is the
time of existence of Universe. Under some assumption preliminary values of rest
masses photons and gravitons are obtained: for a rest mass of photons $
m_{f}\sim 10^{-39}g$, for a rest mass of gravitons $m_{g}\sim10^{-43}g$.

</DOC>
<DOC>
<DOCNO> 99966 </DOCNO>
Representation Functions for Jordanian Quantum Group SL_h(2) and Jacobi


  The explicit expressions of the representation functions (D-functions) for
Jordanian quantum group SL_h(2) are obtained by combination of tensor operator
technique and Drinfeld twist. It is shown that the D-functions can be expressed
in terms of Jacobi polynomials as the undeformed D-functions can. Some of the
important properties of the D-functions for SL_h(2) such as Winger's product
law, recurrence relations, RTT type relations are also presented.

</DOC>
<DOC>
<DOCNO> 13495 </DOCNO>
Dynamics of some constrained lattices


  We consider the dynamics of lattices which have constrained constitutive
units flexible in only their mutual orientations.
 A continuum description is derived through which it is shown that the models
have zero shear velocity, free-particle like internal rotational modes and
volume decreasing linearly with temperature. The relevance of modelsto a range
of problems is pointed out.

</DOC>
<DOC>
<DOCNO> 120466 </DOCNO>
Anomalous radial expansion in central heavy-ion reactions


  The expansion velocity profile in central heavy-ion reactions in the Fermi
energy domain is examined. The radial expansion is non-hubblean and in the
surface region it scales proportional to a higher exponent ($\alpha > 1$) of
the radius. The anomalous expansion velocity profile is accompanied by a power
law nucleon density profile in the surface region. Both these features of
central heavy-ion reactions disappear at higher energies, and the system
follows a uniform Hubble expansion ($\alpha \simeq 1$).

</DOC>
<DOC>
<DOCNO> 178693 </DOCNO>
Effective Field Theory in Nuclear Physics


  I review recent developments in the application of effective field theory to
nuclear physics. Emphasis is placed on precision two-body calculations and
efforts to formulate the nuclear shell model in terms of an effective field
theory.

</DOC>
<DOC>
<DOCNO> 122277 </DOCNO>
Molecular Tracers of the Central 12 pc of the Galactic Center


  We have used the BIMA array to image the Galactic Center with a 19-pointing
mosaic in HCN(1-0), HCO+(1-0), and H 42-alpha emission with 5 km/s velocity
resolution and 13'' x 4'' angular resolution. The 5' field includes the
circumnuclear ring (CND) and parts of the 20 and 50 km/s clouds. HCN(1-0) and
HCO+ trace the CND and nearby giant molecular clouds while the H 42-alpha
emission traces the ionized gas in Sgr A West. We find that the CND has a
definite outer edge in HCN and HCO+ emission at ~45'' radius and appears to be
composed of two or three distinct streams of molecular gas rotating around the
nucleus. Outside the CND, HCN and HCO+ trace dense clumps of high-velocity gas
in addition to optically thick emission from the 20 and 50 km/s clouds. A
molecular ridge of compressed gas and dust, traced in NH3 emission and
self-absorbed HCN and HCO+, wraps around the eastern edge of Sgr A East. Just
inside this ridge are several arcs of gas which have been accelerated by the
impact of Sgr A East with the 50 km/s cloud. HCN and HCO+ emission trace the
extension of the northern arm of Sgr A West which appears to be an independent
stream of neutral and ionized gas and dust originating outside the CND. Broad
line widths and OH maser emission mark the intersection of the northern arm and
the CND. Comparison to previous NH3 and 1.2mm dust observations shows that HCN
and HCO+ preferentially trace the CND and are weaker tracers of the GMCs than
NH3 and dust. We discuss possible scenarios for the emission mechanisms and
environment at the Galactic center which could explain the differences in these
images.

</DOC>
<DOC>
<DOCNO> 118267 </DOCNO>
Strong, Variable Circular Polarization in PKS 1519-273


  We report strong variability in the circular and linear polarization of the
intraday variable source PKS 1519-273. The circular polarization varies on a
timescale of hours to days at frequencies between 1.4 and 8.6 GHz, and is
strongly correlated with variations in the total intensity at 4.8 and 8.6 GHz.
We argue that the variability is due to interstellar scintillation of a highly
compact (15-35 \mu as) component of the source with -3.8\pm 0.4% circular
polarization at 4.8 GHz. We find that no simple model for the circular
polarization can account for both the high magnitude and the frequency
dependence in PKS 1519-273 at centimeter wavelengths.

</DOC>
<DOC>
<DOCNO> 101197 </DOCNO>
The flow completion of a manifold with vector field


  For a vector field $X$ on a smooth manifold $M$ there exists a smooth but not
necessarily Hausdorff manifold $M_\Bbb R$ and a complete vector field $X_\Bbb
R$ on it which is the universal completion of $(M,X)$.

</DOC>
<DOC>
<DOCNO> 101257 </DOCNO>
Groups that do not act by automorphisms of codimension-one foliations


  Let G be a finitely generated group having the property that any action of
any finite-index subgroup of G by homeomorphisms of the circle must have a
finite orbit. (By a theorem of E.Ghys, lattices in simple Lie groups of real
rank at least two have this property.) Suppose that such a G acts on a compact
manifold M by automorphisms of a codimension-one C2 foliation, F. We show that
if F has a compact leaf, then some finite-index subgroup of G fixes a compact
leaf of F. Furthermore, we give sufficient conditions for some finite-index
subgroup of G to fix each leaf of F.

</DOC>
<DOC>
<DOCNO> 102106 </DOCNO>
On FRT-Clifford Algebras


  We study the q-Clifford algebras Cl_q(N,c), called FRT-Clifford algebras,
introduced by Faddeev, Reshetikhin and Takhtajan. It is shown that Cl_q(N,c)
acts on the q-exterior algebra \Lambda(O_q^N). Moreover, explicit formulas for
the embedding of U_q(so_N) into Cl_q(N,c) and its relation to the vector and
spin representations of U_q(so_N) are given and proved.
 Key Words: q-Clifford algebra, Drinfeld-Jimbo algebra, spin representation

</DOC>
<DOC>
<DOCNO> 8362 </DOCNO>
Dynamics of Activated Escape, and Its Observation in a Semiconductor


  We report a direct experimental observation and provide a theory of the
distribution of trajectories along which a fluctuating system moves over a
potential barrier in escape from a metastable state. The experimental results
are obtained for a semiconductor laser with optical feedback. The distribution
of paths displays a distinct peak, which shows how the escaping system is most
likely to move. We argue that the specific features of this distribution may
give an insight into the nature of dropout events in lasers.

</DOC>
<DOC>
<DOCNO> 150979 </DOCNO>
Toroidal Compactification in String Theory from Chern-Simons Theory


  A detailed study of the charge spectrum of three dimensional Abelian
Topological Massive Gauge Theory (TMGT) is given. When this theory is defined
on a manifold with two disconnected boundaries there are induced chiral
Conformal Field Theories (CFT's) on the boundaries which can be interpreted as
the left and right sectors of closed strings. We show that Narain constraints
on toroidal compactification (integer, even, self-dual momentum lattice) have a
natural interpretation in purely three dimensional terms. This is an important
result which is necessary to construct toroidal compactification and heterotic
string from Topological Membrane (TM) approach to string theory. We also derive
the block structure of $c=1$ Rational Conformal Field Theory (RCFT) from the
three dimensional gauge theory.

</DOC>
<DOC>
<DOCNO> 120091 </DOCNO>
Small-scale inviscid accretion discs around black holes


  Gas falling quasi-spherically onto a black hole forms an inner accretion disc
if its specific angular momentum $l$ exceeds $\lmin\sim r_gc$ where $r_g$ is
the Schwarzschild radius. The standard disc model assumes $l\gg\lmin$. We argue
that, in many black-hole sources, accretion flows have angular momenta just
above the threshold for disc formation, $l\simgt\lmin$, and assess the
accretion mechanism in this regime. In a range $\lmin<l<\lcr$, a small-scale
disc forms in which gas spirals fast into the black hole without any help of
horizontal viscous stresses. Such an `inviscid' disc, however, interacts
inelastically with the feeding infall. The disc-infall interaction determines
the dynamics and luminosity of the accretion flow. The inviscid disc radius can
be as large as $14 r_g$, and the energy release peaks at $2r_g$. The disc emits
a Comptonized X-ray spectrum with a break at $\sim 100$ keV. This accretion
regime is likely to take place in wind-fed X-ray binaries and is also possible
in active galactic nuclei.

</DOC>
<DOC>
<DOCNO> 72244 </DOCNO>
Radiative Transitions in Heavy Mesons in a Relativistic Quark Model


  The radiative decays of $D^*$, $B^*$, and other excited heavy mesons are
analyzed in a relativistic quark model for the light degrees of freedom and in
the limit of heavy quark spin-flavor symmetry. The analysis of strong decays
carried out in the corresponding chiral quark model is used to calculate the
strong decays and determine the branching ratios of the radiative $D^*$ decays.
Consistency with the observed branching ratios requires the inclusion of the
heavy quark component of the electromagnetic current and the introduction of an
anomalous magnetic moment for the light quark. It is observed that not only
$D$, but also $B$ meson transitions within a heavy quark spin multiplet are
affected by the presence of the heavy quark current.

</DOC>
<DOC>
<DOCNO> 10238 </DOCNO>
Unstable topography of biphasic surfactant monolayers


  We study the conformation of a heterogeneous surfactant monolayer at a
fluid-fluid interface, near a boundary between two lateral regions of differing
elastic properties. The monolayer attains a conformation of shallow, steep
`mesas' with a height difference of up to 10 nm. If the monolayer is
progressively compressed (e.g. in a Langmuir trough), the profile develops
overhangs and finally becomes unstable at a surface tension of about K(delta
c_0)^2, where (delta c_0) is the difference in spontaneous curvature and K a
bending stiffness. We discuss the relevance of this instability to recently
observed folding behavior in lung surfactant monolayers, and to the absence of
domain structures in films separating oil and water in emulsions.

</DOC>
<DOC>
<DOCNO> 151046 </DOCNO>
Instantons and the monopole-like equations in eight dimensions


  We search for an abelian description of the Yang-Mills instantons on certain
eight dimensional manifolds with the special holonomies $Spin(7)$ and SU(4). By
mimicing the Seiberg-Witten theory in four dimensions, we propose a set of
monopole-like equations governing the 8-dimensional U(1) connections and
spinors, which are supposed to be the dual theory of the nonabelian instantons.
We also give a naive test of the generalized $S$-duality in the abelian sector
of 8-dimensional Yang-Mills theory. Some problems in this approach are pointed
out.

</DOC>
<DOC>
<DOCNO> 170658 </DOCNO>
Multiparticle Quantum Superposition and Stimulated Entanglement by


  A multiparticle quantum superposition state has been generated by a novel
phase-selective parametric amplifier of an entangled two-photon state. This
realization is expected to open a new field of investigations on the
persistence of the validity of the standard quantum theory for systems of
increasing complexity, in a quasi decoherence-free environment. Because of its
nonlocal structure the new system is expected to play a relevant role in the
modern endeavor on quantum information and in the basic physics of
entanglement.

</DOC>
<DOC>
<DOCNO> 150370 </DOCNO>
Noncommutative Super Yang-Mills Theories with 8 Supercharges and Brane


  In this paper we consider D=4 NCSYM theories with 8 supercharges. We study
these theories through a proper type IIA (and M-theory) brane configuration. We
find the one loop beta function of these theories and show that there is an
elliptic curve describing the moduli space of the theory, which is in principle
the same as the curve for the commutative counter-part of our theory. We study
some other details of the dynamics by means of this brane configuration.

</DOC>
<DOC>
<DOCNO> 170790 </DOCNO>
Satisfying Reality


  It is claimed elsewhere that the conscious states of humans must have evolved
together with their biological states, and that an ongoing interaction between
the two must have occurred to insure that they mirror one another in any
species. A quantum mechanical mechanism and an evolutionary model for the
assumed mind/body interaction are described in those papers. The present paper
outlines the related ontological and epistemological assumptions, showing how
the claimed connection between conscious states and physical states should be
understood. Keywords: consciousness, Copenhagen, epistemology, form, Godel,
matter, monism, objective reality, post modernism, psychology, subjective
reality, TOE, undecidability, universals

</DOC>
<DOC>
<DOCNO> 85350 </DOCNO>
The structure of non-spacelike geodesics in dust collapse


  We study here the behaviour of non-spacelike geodesics in dust collapse
models in order to understand the casual structure of the spacetime. The
geodesic families coming out, when the singularity is naked, corresponding to
different initial data are worked out and analyzed. We also bring out the
similarity of the limiting behaviour for different types of geodesics in the
limit of approach to the singularity.

</DOC>
<DOC>
<DOCNO> 84691 </DOCNO>
Estimating Hawking radiation for exotic black holes


  We study about an approximation method of the Hawking radiation. We analyze
an massless scalar field in exotic black hole backgrounds models which have
peculiar properties in black hole thermodynamics (monopole black hole in SO(3)
Einstein-Yang-Mills-Higgs system and dilatoic black hole in
Einstein-Maxwell-dilaton system). A scalar field is assumed not to be couple to
matter fields consisting of a black hole background. Except for extreme black
holes, we can well approximate the Hawking radiaition by `black body' one with
Hawking temperature estimated at a radius of a critical impact parameter.

</DOC>
<DOC>
<DOCNO> 120520 </DOCNO>
The formation of Encke meteoroids and dust trail


  We observed comet 2P/Encke with the Infrared Space Observatory ISOCAM on July
14, 1997 from a particularly favorable viewing geometry above the comet's
orbital plane and at a distance of 0.25 AU. A structured coma was observed,
along with a long, straight dust trail. For the first time, we are able to
observe the path of particles as they evolve from the nucleus to the trail. The
particles that produce the infrared coma are large, with a radiation to
gravitational force ratio beta<0.001 (corresponding to >mm-sized particles).
The dust trail follows the orbit of the comet across our image, with a central
core that is 20,000 km wide, composed of particles with beta<1e-5 (size $\sim
5$ cm) from previous apparitions. The abundant large particles near the comet
pose a significant hazard to spacecraft. There is no evidence of a classical
cometary dust tail due to small particles with beta>0.001, in marked contrast
to other comets like P/Halley or C/Hale-Bopp. The structure of the coma
requires anisotropic emission and that the spin axis of the nucleus to be
nearly parallel to the orbital plane, resulting in strong seasonal variations
of the particle emission. While most of the infrared coma emission is due to
dust produced during the 1997 apparition, the core of the dust trail requires
emissions from previous apparitions. The total mass lost during the 1997
apparition is estimated to be
 2-6e13 g. Comparing to the gas mass loss from ultraviolet observations, the
dust-to-gas mass ratio is 10-30, much higher than has ever been suggested from
visual light observations. Using the recently-measured nuclear diameter, we
find that Encke can only last 3000-10,000 rhoN yr (where rhoN is the nuclear
density in g/cc) at its present mass loss rate.

</DOC>
<DOC>
<DOCNO> 68183 </DOCNO>
The contribution of $\Sigma^* \to \Lambda\pi$ to measured $\Lambda$


  Calculations of the polarization of $\Lambda$ and $\bar{\Lambda}$ particles
after fragmentation of a polarized quark produced in processes like $Z$-decay
and deep inelastic polarized lepton scattering must include $\Lambda$ and
$\bar{\Lambda}$ produced as decay products of $\Sigma^0$ and $\Sigma^*$ as well
as those produced directly. These decay contributions are significant and not
feasibly included in theoretical calculations based on QCD without additional
input from other experimental data. Furthermore these contributions depend on
the spin structure of the $\Sigma^0$ or $\Sigma^*$ and are not directly related
to the structure function of the $\Lambda$

</DOC>
<DOC>
<DOCNO> 122668 </DOCNO>
Remnants from Gamma-Ray Bursts


  We model the intermediate time evolution of a "jetted" gamma-ray burst by two
blobs of matter colliding with the interstellar medium. We follow the
hydrodynamical evolution of this system numerically and calculate the
bremsstrahlung and synchrotron images of the remnant. We find that for a burst
energy of $10^{51}$ erg the remnant becomes spherical after $\sim 5000$ years
when it collects $\sim 50M_\odot$ of interstellar mass. This result is
independent of the exact details of the GRB, such as the opening angle. After
this time a gamma-ray burst remnant has an expanding sphere morphology. The
similarity to a supernova remnant makes it difficult distinguish between the
two at this stage. The expected number of non-spherical gamma-ray burst
remnants is $\sim0.05$ per galaxy for a beaming factor of 0.01 and a burst
energy of $10^{51}$ erg. Our results suggest that that the double-shell object
DEM L 316 is not a GRB remnant.

</DOC>
<DOC>
<DOCNO> 40434 </DOCNO>
Differential cross section for W boson production as a function of


  We report a measurement of the differential cross section for W boson
production as a function of its transverse momentum in proton-antiproton
collisions at sqrt{s} = 1.8 TeV. The data were collected by the D0 experiment
at the Fermilab Tevatron Collider during 1994-1995 and correspond to an
integrated luminosity of 85 pb^{-1}. The results are in good agreement with
quantum chromodynamics over the entire range of transverse momentum.

</DOC>
<DOC>
<DOCNO> 99499 </DOCNO>
Topological AE(0)-groups


  We investigate topological AE(0) -groups class of which contains the class of
Polish groups as well as the class of all locally compact groups. We establish
the existence of an universal AE(0) -group of a given weight as well as the
existence of an universal action of AE(0) -group of a given weight on a AE(0)
-space of the same weight. A complete characterization of closed subgroups of
powers of the symmetric group is obtained. It is also shown that every AE
(0)-group is Baire isomorphic to the product of Polish groups. These results
are obtained by using the spectral descriptions of AE(0)-groups which are
presented in Section 3.

</DOC>
<DOC>
<DOCNO> 119696 </DOCNO>
The likely detection of pulsed high-energy gamma-ray emission from


  We report circumstantial evidence for the first detection of pulsed
high-energy gamma-ray emission from a millisecond pulsar, PSR J0218+4232, using
data collected with the Energetic Gamma Ray Experiment (EGRET) on board the
Compton Gamma Ray Observatory (CGRO). The EGRET source 3EG J0222+4253 is shown
to be spatially consistent with PSR J0218+4232 for the energy range 100 - 300
MeV. Above 1 GeV the nearby BL Lac 3C 66A is the evident counterpart, and
between 300 MeV and 1 GeV both sources contribute to the gamma-ray excess.
Folding the 100-1000 MeV photons with an accurate radio ephemeris of PSR
J0218+4232 yields a double peaked pulse profile with a ~3.5 sigma modulation
significance and with a peak separation of ~0.45 similar to the 0.1-10 keV
pulse profile.

</DOC>
<DOC>
<DOCNO> 10198 </DOCNO>
Localization length and impurity dielectric susceptibility in the


  We have determined the localization length \xi and the impurity dielectric
susceptibility \chi_{\rm imp} as a function of Ga acceptor concentrations (N)
in nominally uncompensated ^{70}Ge:Ga just below the critical concentration
(N_c) for the metal-insulator transition. Both \xi and \chi_{\rm imp} diverge
at N_c according to the functions \xi\propto(1-N/N_c)^{-\nu} and \chi_{\rm
imp}\propto(N_c/N-1)^{-\zeta}, respectively, with \nu=1.2\pm0.3 and
\zeta=2.3\pm0.6 for 0.99N_c< N< N_c. Outside of this region (N<0.99N_c), the
values of the exponents drop to \nu=0.33\pm0.03 and \zeta=0.62\pm0.05. The
effect of the small amount of compensating dopants that are present in our
nominally uncompensated samples, may be responsible for the change of the
critical exponents at N\approx0.99N_c.

</DOC>
<DOC>
<DOCNO> 122807 </DOCNO>
The Be/X-ray binary LS 992/RX J0812.4-3114: physical parameters and


  We present the first long-term optical and infrared study of the optical
counterpart to the source RX J0812.4-3114, an X-ray pulsar with a Be type
companion. During the period covered by the observations the profile of some
Balmer lines changed from absorption to emission and back again to absorption.
Contemporaneously, the infrared magnitudes varied by more than 0.8 mag. This
long-term variability is interpreted as the formation and subsequent
dissipation of the Be star's disc. The building up of the disc ended up in an
active X-ray state characterised by regular outbursts occurring at 80 day
intervals. The overall duration of the formation/dissipation of the disc is
found to be < 4.3 years. Optical spectroscopic and infrared photometric
observations were used to refine the spectral type of the primary (B0.2IV) and
to monitor the circumstellar envelope around the Be star. UBVRI and uvby\beta
photometric observations allowed the determination of the astrophysical
parameters of the optical companion.

</DOC>
<DOC>
<DOCNO> 122417 </DOCNO>
CMBR in G\"{o}del Universe:A possible test to Einstein-Cartan gravity?


  A rotating universe represented by the G\"{o}del metric in spacetimes with
Cartan torsion is investigated where the Cosmic Microwave Background Radiation
(CMBR) is computed from the G\"{o}del rotation of the universe and the spin
density of the spinning fluid in Einstein-Cartan gravity.The autoparallel
equation in Riemann-Cartan spacetime is shown to lead to the evolution equation
of the cosmological perturbation where the spin-rotation coupling is the source
of the growth of inhomogeneities.It is shown that temperature anisotropy is
within the limits of COBE constraint yielding a value of
$\frac{{\delta}T}{T}=10^{-7}$.This result opens the possibility of testing
Einstein-Cartan gravity from a cosmological experiment such as PLANCK or MAP.

</DOC>
<DOC>
<DOCNO> 169613 </DOCNO>
Quantum cryptography with 3-state systems


  We consider quantum cryptographic schemes where the carriers of information
are 3-state particles. One protocol uses four mutually unbiased bases and
appears to provide better security than obtainable with 2-state carriers.
Another possible method allows quantum states to belong to more than one basis.
The security is not better, but many curious features arise.

</DOC>
<DOC>
<DOCNO> 121876 </DOCNO>
Short-timescale Fluctuations in the Difference Light Curves of QSO


  From optical R band data of the double quasar QSO 0957+561A,B, we made two
new difference light curves (about 330 days of overlap between the time-shifted
light curve for the A image and the magnitude-shifted light curve for the B
image). We observed noisy behaviours around the zero line and no
short-timescale events (with a duration of months), where the term event refers
to a prominent feature that may be due to microlensing or another source of
variability. Only one event lasting two weeks and rising - 33 mmag was found.
Measured constraints on the possible microlensing variability can be used to
obtain information on the granularity of the dark matter in the main lensing
galaxy and the size of the source. In addition, one can also test the ability
of the observational noise to cause the rms averages and the local features of
the difference signals. We focused on this last issue. The combined
photometries were related to a process consisting of an intrinsic signal plus a
Gaussian observational noise. The intrinsic signal has been assumed to be
either a smooth function (polynomial) or a smooth function plus a stationary
noise process or a correlated stationary process. Using these three pictures
without microlensing, we derived some models totally consistent with the
observations. We finally discussed the sensitivity of our telescope (at Teide
Observatory) to several classes of microlensing variability.

</DOC>
<DOC>
<DOCNO> 119702 </DOCNO>
Type Ia Supernovae and their implications for cosmology


  Models for Type Ia Supernovae (SNe Ia) are reviewed. It is shown that there
are strong reasons to believe that most SNe Ia represent thermonuclear
disruptions of C-O white dwarfs, when these white dwarfs reach the
Chandrasekhar limit and ignite carbon at their centers.
  Different progenitor scenarios are reviewed critically and the strengths and
weaknesses of each scenario are presented in detail. It is argued that
theoretical considerations currently favor single-degenerate models, in which
the white dwarf accretes from a subgiant or giant companion. However, it is
still possible that more than one progenitor class contributes to the observed
sample. The relation of the different models to the use of SNe Ia for the
determination of cosmological parameters is discussed. It is shown that while
the observed diversity of SNe Ia may argue for the existence of different
progenitor classes, this does not affect the interpretation of an accelerating
expansion of the universe.

</DOC>
<DOC>
<DOCNO> 100498 </DOCNO>
An Eulerian-Lagrangian approach to the Navier-Stokes equations


  This work presents an approach to the Navier-Stokes equations that is phrased
in unbiased Eulerian coordinates, yet describes objects that have Lagrangian
significance: particle paths, their dispersion and diffusion. The commutator
between Lagrangian and Eulerian derivatives plays an important role in the
Navier-Stokes equations: it contributes a singular perturbation to the Euler
equations, in addition to the Laplacian. Bounds for the Lagrangian
displacements, their first and second derivatives are obtained without
assumptions. Some of these rigorous bounds can be interpreted in terms of the
heuristic Richardson law of pair dispersion in turbulent flows.

</DOC>
<DOC>
<DOCNO> 121388 </DOCNO>
Neutrinos and the Highest Energy Cosmic Rays


  Observation of Ultra High Energy Cosmic Rays (UHECR) -whose energy exceeds
$10^20$eV- is still a puzzle for modern astrophysics. The transfer of more than
16 Joules to a microscopic particle can hardly be achieved, even in the most
powerful cosmic accelerators such as AGN's, GRB's or FR-II radio galaxy lobes.
Potential sources must also lie within 100 Mpc of the Earth as the interaction
length of protons, nuclei or photons is less than 10Mpc. However no visible
counterpart of those sources has been observed. Calling upon new physics such
as Topological Defect interactions or Super Massive Relic Particle decays is
therefore very tempting, but such objects are yet to be proven to exist. Due to
the very low flux of UHECR only very large dedicated experiments, such as the
Auger observatories, will allow to shed some light on the origin of those
cosmic rays. In this quest neutrinos, if they can be detected, are an
invaluable messengers of the nature of the sources.

</DOC>
<DOC>
<DOCNO> 117744 </DOCNO>
Broad-band colour evolution of star clusters


  We briefly review the main features in the broad-band colour evolution of
star clusters, over the complete age interval from 10^7 to 10^(10) yr. The
emphasis is in the problem of age-dating distant young clusters (<2 Gyr) from
their integrated colours. It is shown that U-B and B-V are less sensitive to
metallicity than colours involving red pass-bands, like V-I, at least up to
ages of some few Gyr. Since U-B and B-V are determined by well-understood and
well-populated evolutionary stages, they are also less affected by theoretical
uncertainties and by the ubiquitous effect of stochastic colour dispersion. The
latter effects become important for the V-K colour. Thus, we argue that U-B and
B-V are, presently, the more suitable broad-band colours for age-dating distant
clusters. For other potentially useful colours like V-R and V-I, empirical
tests of their evolution are still missing.

</DOC>
<DOC>
<DOCNO> 116254 </DOCNO>
Statistical mechanics of neocortical interactions: Reaction time


  A statistical mechanics of neuronal interactions (SMNI) is explored as
providing some substance to a physiological basis of the g factor. Some
specific elements of SMNI, previously used to develop a theory of short-term
memory (STM) and a model of electroencephalography (EEG) are key to providing
this basis. Specifically, Hick's Law, an observed linear relationship between
reaction time (RT) and the information storage of STM, in turn correlated to a
RT-g relationship, is derived.

</DOC>
<DOC>
<DOCNO> 85027 </DOCNO>
An exact solution for 2+1 dimensional critical collapse


  We find an exact solution in closed form for the critical collapse of a
scalar field with cosmological constant in 2+1 dimensions. This solution agrees
with the numerical simulation done by Pretorius and Choptuik of this system.

</DOC>
<DOC>
<DOCNO> 69648 </DOCNO>
A Consistent Calculation of Heavy Meson Decay Constants and Transition


  Within the complete heavy quark effective field theory (HQEFT), the QCD sum
rule approach is used to evaluate the decay constants including 1/m_Q
corrections and the Isgur-Wise function and other additional important wave
functions concerned at 1/m_Q for the heavy-light mesons. The 1/m_Q corrections
to the scaling law f_M \sim F/\sqrt{m_M} are found to be small in HQEFT, which
demonstrates again the validity of 1/m_Q expansion in HQEFT. It is also shown
that the residual momentum v.k of heavy quark within hadrons does be around the
binding energy \bar{\Lambda} of the heavy hadrons. The calculations presented
in this paper provide a consistent check on the HQEFT and shows that the HQEFT
is more reliable than the usual HQET for describing a slightly off-mass shell
heavy quark within hadron as the usual HQET seems to lead to the breakdown of
1/m_Q expansion in evaluating the meson decay constants. It is emphasized that
the introduction of the `dressed heavy quark' mass is useful for the
heavy-light mesons (Qq) with m_Q >> \bar{\Lambda} >> m_q, while for heavy-heavy
bound states (\psi_1\psi_2) with masses m_1, m_2 >> \bar{\Lambda}, like
bottom-charm hadrons or similarly for muonium in QED, one needs to treat both
particles as heavy effective particles via 1/m_1 and 1/m_2 expansions and
redefine the effective bound states and modified `dressed heavy quark' masses
within the HQEFT.

</DOC>
<DOC>
<DOCNO> 170342 </DOCNO>
Nonclassical Phenomena in Multiphoton Interferometry: More Stringent


  The thesis is divided into three parts. In the first part a new theoretical
analysis of interferometric experiments by Alley-Shih, Ou-Mandel and the
entanglement swapping experiment is performed. It is shown that the double- and
single-photon distinguishability is not necessary for the experiments to be
genuine tests against local realism. In the second part, basing on simple
geometrical properties of Hilbert space, new, stronger Bell inequalities for M
qubits in a maximally entangled state are derived. Application of the same
method to two maximally entangled qubits yields an inequality for all possible
positions of the local measuring apparatus. Finally, the series of the
Greenberger-Horne- Zeilinger paradoxes for M maximally entangled quNits
observed via symmetric unbiased 2N ports is derived. The last part of the
thesis is devoted to the numerical approach to the Bell theorem. The necessary
and sufficient conditions for the violation of local realism in the case of two
and three maximally entangled qubits, on which each observer performs up to 10
(two qubits) and up to 5 (three qubits) local measurements, are shown. It is
also numerically shown that in the case of two maximally entangled quNits (3 <
N < 9) a properly defined magnitude of violation increases with N. In both
cases the approach neither involves any simplifications, or additional
assumptions, nor does it utilise any symmetries of the problem.

</DOC>
<DOC>
<DOCNO> 67658 </DOCNO>
Cosmic rays and neutrino interactions beyond the standard model


  Some solutions of the hierarchy problem of particle physics can lead to
significantly increased neutrino cross sections beyond the electroweak scale.
We discuss some consequences for and constraints resulting from cosmic ray
physics.

</DOC>
<DOC>
<DOCNO> 69616 </DOCNO>
The Scale Dependence of Inclusive ep Scattering in the Resonance Region


  We examine the scale dependence in the resonance region of inclusive ep
scattering. In particular we discuss the invariants other than Q^2, which have
been proposed as a scale for pQCD evolution in a kinematical regime where both
infrared singularities and power corrections are expected to be largest. We
show that the region where most of the present data are available, can be
described using NLO pQCD evolution at fixed invariant mass, W^2, plus a leading
order power correction term. We find that the coefficient of the power
correction at W^2 < 4 GeV^2 is relatively small, i.e. comparable in size to the
one obtained in the large W^2 region.

</DOC>
<DOC>
<DOCNO> 101576 </DOCNO>
Kobayashi-Royden vs. Hahn pseudometric in ${\Bbb C}^2$


  For a domain $D\subset{\Bbb C}$ the Kobayashi--Royden $\kappa$ and Hahn $h$
pseudometrics are equal iff $D$ is simply connected. Overholt showed that for
$D\subset{\Bbb C}^n$, $n\geq3$, we have $h_D\equiv\kappa_D$. Let
$D_1,D_2\subset{\Bbb C}$. The aim of this paper is to show that $h_{D_1\times
D_2}\equiv\kappa_{D_1\times D_2}$ iff at least one of $D_1$, $D_2$ is simply
connected or biholomorphic to ${\Bbb C}\setminus\{0\}$. In particular, there
are domains $D\subset{\Bbb C}^2$ for which $h_D\not\equiv\kappa_D$.

</DOC>
<DOC>
<DOCNO> 102208 </DOCNO>
Homogenization of oscillating boundaries and applications to thin films


  We prove a homogenization result for integral functionals in domains with
oscillating boundaries, showing that the limit is defined on a degenerate
Sobolev space. We apply this result to the description of the asymptotic
behaviour of thin films with fast-oscillating profile, proving that they can be
described by first applying the homogenization result above and subsequently a
dimension-reduction technique.

</DOC>
<DOC>
<DOCNO> 83212 </DOCNO>
Reasoning with Axioms: Theory and Pratice


  When reasoning in description, modal or temporal logics it is often useful to
consider axioms representing universal truths in the domain of discourse.
Reasoning with respect to an arbitrary set of axioms is hard, even for
relatively inexpressive logics, and it is essential to deal with such axioms in
an efficient manner if implemented systems are to be effective in real
applications. This is particularly relevant to Description Logics, where
subsumption reasoning with respect to a terminology is a fundamental problem.
Two optimisation techniques that have proved to be particularly effective in
dealing with terminologies are lazy unfolding and absorption. In this paper we
seek to improve our theoretical understanding of these important techniques. We
define a formal framework that allows the techniques to be precisely described,
establish conditions under which they can be safely applied, and prove that,
provided these conditions are respected, subsumption testing algorithms will
still function correctly. These results are used to show that the procedures
used in the FaCT system are correct and, moreover, to show how efficiency can
be significantly improved, while still retaining the guarantee of correctness,
by relaxing the safety conditions for absorption.

</DOC>
<DOC>
<DOCNO> 116306 </DOCNO>
The Iron Project


  Recent advances in theoretical atomic physics have enabled large-scale
calculation of atomic parameters for a variety of atomic processes with high
degree of precision. The development and application of these methods is the
aim of the Iron Project. At present the primary focus is on collisional
processes for all ions of iron, Fe I- FeXXVI, and other iron-peak elements; new
work on radiative processes has also been initiated. Varied applications of the
Iron Project work to X-ray astronomy are discussed, and more general
applications to other spectral ranges are pointed out. The IP work forms the
basis for more specialized projects such as the RMaX Project, and the work on
photoionization/recombination, and aims to provide a comprehensive and
self-consistent set of accurate collsional and radiative cross sections, and
transition probabilities, within the framework of relativistic close coupling
formulation using the Breit-Pauli R-Matrix method. An illustrative example is
presented of how the IP data may be utilised in the formation of X-ray spectra
of the K$\alpha$ complex at 6.7 keV from He-like Fe XXV.

</DOC>
<DOC>
<DOCNO> 120308 </DOCNO>
Computational AstroStatistics: Fast Algorithms and Efficient Statistics


  We present initial results on the use of Mixture Models for density
estimation in large astronomical databases. We provide herein both the
theoretical and experimental background for using a mixture model of Gaussians
based on the Expectation Maximization (EM) Algorithm. Applying these analyses
to simulated data sets we show that the EM algorithm - using the both the AIC &
BIC penalized likelihood to score the fit - can out-perform the best kernel
density estimate of the distribution while requiring no ``fine-tuning'' of the
input algorithm parameters. We find that EM can accurately recover the
underlying density distribution from point processes thus providing an
efficient adaptive smoothing method for astronomical source catalogs. To
demonstrate the general application of this statistic to astrophysical problems
we consider two cases of density estimation; the clustering of galaxies in
redshift space and the clustering of stars in color space. From these data we
show that EM provides an adaptive smoothing of the distribution of galaxies in
redshift space (describing accurately both the small and large-scale features
within the data) and a means of identifying outliers in multi-dimensional
color-color space (e.g. for the identification of high redshift QSOs).
Automated tools such as those based on the EM algorithm will be needed in the
analysis of the next generation of astronomical catalogs (2MASS, FIRST, PLANCK,
SDSS) and ultimately in the development of the National Virtual Observatory.

</DOC>
<DOC>
<DOCNO> 10158 </DOCNO>
Coulomb blockade in one-dimensional arrays of high conductance tunnel


  Properties of one-dimensional (1D) arrays of low Ohmic tunnel junctions 
(i.e. junctions with resistances comparable to, or less than, the quantum
resistance $R_{\rm q}\equiv h/e^2\approx 25.8$ k$\Omega$) have been studied
experimentally and theoretically. Our experimental data demonstrate that -- in
agreement with previous results on single- and double-junction systems --
Coulomb blockade effects survive even in the strong tunneling regime and are
still clearly visible for junction resistances as low as 1 k$\Omega$. We have
developed a quasiclassical theory of electron transport in junction arrays in
the strong tunneling regime. Good agreement between the predictions of this
theory and the experimental data has been observed. We also show that, due to
both heating effects and a relatively large correction to the linear
relation between the half-width of the conductance dip around zero bias
voltage, $V_{1/2}$, and the measured electronic temperature, such arrays are
inferior to those conventionally used in the Coulomb Blockade Thermometry
(CBT). Still, the desired correction to the half-width, $\Delta V_{1/2}$, can
be determined rather easily and it is proportional to the magnitude of the
conductance dip around zero bias voltage, $\Delta G$. The constant of
proportionality is a function of the ratio of the junction and quantum
resistances, $R/R_{\rm q}$, and it is a pure strong tunneling effect.

</DOC>
<DOC>
<DOCNO> 151912 </DOCNO>
Equivalent Relations between Quantum Dynamics as Derived from a Gauge


  Equivalent relations between quantum mechanical systems in the
Robertson-Walker (RW) background metric and quantum dynamics with an induced
quadratic background potential are derived in this work. Two elementary
applications, which include an algebraic derivation of the evolution operator
for a simple harmonic oscillator without using any special function or the path
integral technique, and a moving soliton solution of a free particle in an
oscillating universe, are presented to illustrate the use of these equivalent
relations.

</DOC>
<DOC>
<DOCNO> 85039 </DOCNO>
The Energy of a Dyonic Dilaton Black Hole


  We calculate the energy distribution of a dyonic dilaton black hole by using
the Tolman's energy-momentum complex. All the calculations are performed in
quasi-Cartesian coordinates. The energy distribution of the dyonic dilaton
black hole depends on the mass, electric charge, magnetic charge and asymptotic
value of the dilaton. We get the same result as obtained by Y-Ching Yang,
Ching-Tzung Yeh, Rue-Ron Hsu and Chin-Rong Lee by using the Einstein's
prescription.

</DOC>
<DOC>
<DOCNO> 9858 </DOCNO>
A disorder analysis of the Ising model


  Lattice studies of monopole condensation in QCD are based on the construction
of a disorder parameter, a creation operator of monopoles which is written in
terms of the gauge fields. This procedure is expected to work for any system
which presents duality. We check it on the Ising model in 2d, which is exactly
solvable. The output is an amusing exercise in statistical mechanics.

</DOC>
<DOC>
<DOCNO> 83304 </DOCNO>
Examples, Counterexamples, and Enumeration Results for Foldings and


  We investigate how to make the surface of a convex polyhedron (a polytope) by
folding up a polygon and gluing its perimeter shut, and the reverse process of
cutting open a polytope and unfolding it to a polygon. We explore basic
enumeration questions in both directions: Given a polygon, how many foldings
are there? Given a polytope, how many unfoldings are there to simple polygons?
Throughout we give special attention to convex polygons, and to regular
polygons. We show that every convex polygon folds to an infinite number of
distinct polytopes, but that their number of combinatorially distinct gluings
is polynomial. There are, however, simple polygons with an exponential number
of distinct gluings.
  In the reverse direction, we show that there are polytopes with an
exponential number of distinct cuttings that lead to simple unfoldings. We
establish necessary conditions for a polytope to have convex unfoldings,
implying, for example, that among the Platonic solids, only the tetrahedron has
a convex unfolding. We provide an inventory of the polytopes that may unfold to
regular polygons, showing that, for n>6, there is essentially only one class of
such polytopes.

</DOC>
<DOC>
<DOCNO> 116520 </DOCNO>
Technique for measuring the parameters of polarization of an ultrasonic


  Method for precise measurements of the ellipticity and rotation of the
polarization of a transverse ultrasonic wave is presented. It is applicable for
investigating the acoustic analogs of the Faraday, Cotton-Mouton, and Kerr
effects. The technique consists of measuring amplitude of the voltage on the
receiving piezoelectric transducer at a certain magnetic induction B, relative
to an initial one using three different positions of the transducer with futher
processing the data with the formulars given in the paper.

</DOC>
<DOC>
<DOCNO> 122096 </DOCNO>
Dense Gas in Nearby Galaxies: XIV. Detection of hot ammonia in Maffei 2


  The (J,K) = (1,1), (2,2), (3,3), and (4,4) inversion lines of ammonia (NH3)
have been detected toward the nuclear 40'' sized bar of the nearby spiral
galaxy Maffei 2. The relative intensities of the ammonia lines are
characterized by a rotational temperature of 85 K. This is higher than
rotational temperatures measured toward IC342 and most Galactic Center clouds,
implying kinetic temperatures of at least 100 K. Since the kinetic temperature
of the gas is larger than that of the dust, NH3 is tracing a particularly dense
warm gas component that is heated by young massive stars, cloud-cloud
collisions, or ion-slip heating in the nuclear starburst. The gas north of the
nucleus (V(LSR} = -80 km/s) is more highly excited than the gas further south
(+6 km/s). This asymmetry might be related to a pronounced morphological
distortion that is observed in the north-eastern part of the galaxy.

</DOC>
<DOC>
<DOCNO> 84112 </DOCNO>
Generalised scalar-tensor theory in the Bianchi type I model


  We use a conformal transformation to find solutions to the generalised
scalar-tensor theory, with a coupling constant dependent on a scalar field, in
an empty Bianchi type I model. We describe the dynamical behaviour of the
metric functions for three different couplings: two exact solutions to the
field equations and a qualitative one are found. They exhibit non-singular
behaviours and kinetic inflation. Two of them admit both General Relativity and
string theory in the low-energy limit as asymptotic cases.

</DOC>
<DOC>
<DOCNO> 152336 </DOCNO>
AdS/CFT correspondence, conformal anomaly and quantum corrected entropy


  The role of conformal anomaly in AdS/CFT and related issues is clarified. The
comparison of holographic and QFT conformal anomalies (with account of brane
quantum gravity contribution) indicates on the possibility for brane quantum
gravity to occur within AdS/CFT set-up. 3d quantum induced inflationary (or
hyperbolic) brane-world is shown to be realized in frames of AdS3/CFT2
correspondence where the role of 2d brane cosmological constant is played by
effective tension due to two-dimensional conformal anomaly. The dynamical
equations to describe 4d FRW-Universe with account of quantum effects produced
by conformal anomaly are obtained. The quantum corrected energy, pressure and
entropy are found. Dynamical evolution of entropy bounds in inflationary
Universe is estimated and its comparison with quantum corrected entropy is
done. It is demonstrated that entropy bounds for quantum corrected entropy are
getting the approximate ones and occur for some limited periods of evolution of
inflationary Universe.

</DOC>
<DOC>
<DOCNO> 150991 </DOCNO>
Branes and Fluxes in D=5 Calabi-Yau Compactifications of M-Theory


  We discuss Poincare three-brane solutions in D=5 M-Theory compactifications
on Calabi-Yau (CY) threefolds with G-fluxes. We show that the vector moduli
freeze at an attractor point. In the case with background flux only, the
spacetime geometry contains a zero volume singularity with the three-brane and
the CY space shrinking simultaneously to a point. This problem can be avoided
by including explicit three-brane sources. We consider two cases in detail: a
single brane and, when the transverse dimension is compactified on a circle, a
pair of branes with opposite tensions.

</DOC>
<DOC>
<DOCNO> 122661 </DOCNO>
Constraints on the tensor mode from large scale structure observations


  Observational data on the large scale structure (LSS) of the Universe are
used to establish an upper limit for the amplitude of the tensor mode
marginalized over all other cosmological parameters within the class of
adiabatic inflationary models. It is shown that the upper 1$\sigma$ limit for
the contribution of a tensor mode to the COBE DMR data is T/S$<1$.

</DOC>
<DOC>
<DOCNO> 14001 </DOCNO>
Material-specific spin filtering in ferromagnet/superconductor ballistic


  We study spin-dependent electronic transport across
ferromagnet/superconductor ballistic junctions modeled using tight-binding
Hamiltonians with s, p and d orbitals and material-specific parameters. We show
that by accurately modeling the band structure of the bulk materials, one can
reproduce the measured differential conductance of Cu/Pb nanocontacts. In
contrast the differential conductance of Co/Pb contacts can only be reproduced
if an enhanced magnetic moment is present at the interface.

</DOC>
<DOC>
<DOCNO> 69801 </DOCNO>
The eta and eta' mesons in QCD


  We study the flavour singlet pseudoscalar mesons from first principles using
lattice QCD. We explore the quark content of the $\eta$ and $\eta'$ mesons and
we discuss their decay constants.

</DOC>
<DOC>
<DOCNO> 10132 </DOCNO>
Two-dimensional hydrodynamic lattice-gas simulations of binary


  The behaviour of two dimensional binary and ternary amphiphilic fluids under
flow conditions is investigated using a hydrodynamic lattice gas model. After
the validation of the model in simple cases (Poiseuille flow, Darcy's law for
single component fluids), attention is focussed on the properties of binary
immiscible fluids in porous media. An extension of Darcy's law which explicitly
admits a viscous coupling between the fluids is verified, and evidence of
capillary effects are described. The influence of a third component, namely
surfactant, is studied in the same context. Invasion simulations have also been
performed. The effect of the applied force on the invasion process is reported.
As the forcing level increases, the invasion process becomes faster and the
residual oil saturation decreases. The introduction of surfactant in the
invading phase during imbibition produces new phenomena, including
emulsification and micellisation. At very low fluid forcing levels, this leads
to the production of a low-resistance gel, which then slows down the progress
of the invading fluid. At long times (beyond the water percolation threshold),
the concentration of remaining oil within the porous medium is lowered by the
action of surfactant, thus enhancing oil recovery. On the other hand, the
introduction of surfactant in the invading phase during drainage simulations
slows down the invasion process -- the invading fluid takes a more tortuous
path to invade the porous medium -- and reduces the oil recovery (the residual
oil saturation increases).

</DOC>
<DOC>
<DOCNO> 70917 </DOCNO>
Suppression of Quarkonium Production in Heavy Ion Collisions at RHIC and


  A model for the production of quarkonium states in the midrapidity region at
RHIC and LHC energy range is presented which explores well understood
properties of QCD only. An increase of the quarkonium hadronisation time with
the initial energy leads to a gradual change of the most important phenomena
from fixed target- to collider-energies. We evaluate nuclear effects in the
quarkonium production due to medium modification of the momentum distribution
of the heavy quarks produced in the hard interactions, i.e. due to the
broadening of the transverse momentum distribution. Other nuclear effects, i.e.
nuclear shadowing and parton energy loss, are also evaluated.

</DOC>
<DOC>
<DOCNO> 12902 </DOCNO>
Magnetic-history-dependent nanostructural and resistivity changes in


  We show that nanostructure and resistivity of Pr0.5Ca0.5Mn0.98Cr0.02O3 are
sensitive to whether the sample is zero-field-cooled (ZFC) of field-cooled (FC)
either in the 'self magnetic field (H = 2 T)' of the electron microscope or
under the external magnetic field of 2 T. FC resistivity at H = 2 T is lower
than ZFC values below 140 K. The average value of the chare-orbital modulation
vector (q = 0.44) of the FC crystallites is lower than that of the ZFC
cystallites (q = 0.48) and the FC crystallites exhibit numerous defects like
discommensuration, dislocations and regios with loss of superstructures
compared to the ZFC crystallites.

</DOC>
<DOC>
<DOCNO> 169725 </DOCNO>
Decoherence and Planck's Radiation Law


  The foundations of environment-induced decoherence theory are discussed and
the role of unphysical assumptions is pointed out. An alternative
interpretation of decoherence is proposed.

</DOC>
<DOC>
<DOCNO> 99703 </DOCNO>
Higher order scattering on asymptotically Euclidean Manifolds


  We develop a scattering theory for perturbations of powers of the Laplacian
on asymptotically Euclidean manifolds. The (absolute) scattering matrix is
shown to be a Fourier integral operator associated to the geodesic flow at time
\pi on the boundary. Furthermore, it is shown that on \Real^n the asymptotics
of certain short-range perturbations of \Delta^k can be recovered from the
scattering matrix at a finite number of energies.

</DOC>
<DOC>
<DOCNO> 40665 </DOCNO>
Measuring the Top Yukawa coupling to a heavy Higgs boson at future e+e-


  The determination of the Yukawa coupling of the top quark to the Higgs boson
is one of the most important measurements that a future e^+e^- linear collider
could provide. For a Higgs boson of mass greater than 350 GeV, this coupling
can be determined using the Higgs resonant contribution to t \bar t production
from W^+ W^- fusion at TeV energies. We have made a careful evaluation of the
significance with which the signal of a Higgs decaying to t \bar t pairs could
be observed at future e^+ e^- linear colliders, with center of mass energies
close to 1 TeV and an integrated luminosity of 1 ab^{-1}. We find that a signal
significance greater than 5 \sigma and a relative error in the top Yukawa
measurement better than 10% can be achieved, for Higgs masses in the 350-500
GeV and 350-650 GeV ranges at facilities with 800 GeV and 1 TeV energies
respectively.

</DOC>
<DOC>
<DOCNO> 12251 </DOCNO>
Superconducting phase coherence in the presence of a pseudogap: Relation


  In this paper we demonstrate how, using a natural generalization of BCS
theory, superconducting phase coherence manifests itself in phase insensitive
measurements, when there is a smooth evolution of the excitation gap \Delta
from above to below Tc. In this context, we address the underdoped cuprates.
Our premise is that just as Fermi liquid theory is failing above Tc, BCS theory
is failing below. The order parameter \Delta_{sc} is different from the
excitation gap \Delta. Equivalently there is a (pseudo)gap in the excitation
spectrum above Tc which is also present in the underlying normal state of the
superconducting phase, and can be directly inferred from specific heat and
vortex core experiments. At the same time many features of BCS theory, e.g.,
fermionic quasiparticles below Tc, are clearly present. These observations can
be reconciled by a natural extension of BCS theory, which includes finite
center-of-mass momentum pair excitations, in addition to the usual fermionic
quasiparticles. Applying this theory we find that the Bose condensation of
Cooper pairs, which is reflected in \Delta_{sc}, leads to sharp peaks in the
spectral function once $T \le T_c$. These are manifested in ARPES spectra as
well as in specific heat jumps, which become more like the behavior in a
\lambda transition as the pseudogap develops. We end with a discussion of
tunneling experiments and condensation energy issues. Comparison between
theoretical and experimental plots of C_v, and of tunneling and vortex core
spectroscopy measurements is good.

</DOC>
<DOC>
<DOCNO> 118096 </DOCNO>
The giant radio galaxy 8C0821+695 and its environment


  We present new VLA and Effelsberg observations of the radio galaxy
8C0821+695. We have obtained detailed images in total intensity and
polarization of this 2 Mpc sized giant. The magnetic field has a configuration
predominantly parallel to the source main axis. We observe Faraday rotation at
low frequencies, most probably produced by an ionized medium external to the
radio source. The spectral index distribution is that typical of FR II radio
galaxies, with spectral indices gradually steepening from the source extremes
towards the core. Modeling the spectrum in the lobes using standard synchrotron
loss models yields the spectral age of the source and the mean velocity of the
jet-head with respect to the lobe material. The existence of a possible
backflow in the lobe is considered to relate spectral with dynamical
determinations of the age and the velocity with respect to the external medium.
Through a very simple model, we obtain a physical characterization of the jets
and the external medium in which the radio galaxy expands. The results in
8C0821+695 are consistent with a relativistic jet nourishing the lobes which
expand in a hot, low density halo. We infer a deceleration of the source
expansion velocity which we explain through a progressive increase in the
hot-spot size.

</DOC>
<DOC>
<DOCNO> 84386 </DOCNO>
On the Axiomatics of the 5-dimensional Projective Unified Field Theory


  For more than 40 years E.Schmutzer has developed a new approach to the
(5-dimensional) projective relativistic theory which he later called Projective
Unified Field Theory (PUFT). In the present paper we introduce a new axiomatics
for Schmutzer's theory. By means of this axiomatics we can give a new
geometrical interpretation of the physical concept of the PUFT.

</DOC>
<DOC>
<DOCNO> 40638 </DOCNO>
A Measurement of the QCD Colour Factors using Event Shape Distributions


  Measurements of the QCD colour factors C_A and C_F and of the number of
active quark flavours n_f in the process e+e- -> hadrons at high energy are
presented. They are based on fits of O(alpha_S**2)+NLLA QCD calculations to
distributions of the event shape observables 1-T, C, B_T and B_W measured at
centre-of-mass energies from 14 GeV to 189 GeV. Hadronisation effects are
approximated with power correction calculations which also depend on the QCD
gauge structure. In this approach potential biases from hadronisation models
are reduced. Our results for individually measured quantities are n_f = 5.64 +-
1.35, C_A = 2.88 +- 0.27 and C_F = 1.45 +- 0.27 in good agreement with QCD
based on the SU(3) symmetry group where n_f=5 for the energies considered here,
C_A=3 and C_F=4/3. From simultaneous fits of C_A and C_F we find C_A = 2.84 +-
0.24 and C_F = 1.29 +- 0.18, which is also in good agreement with the QCD
expectation.

</DOC>
<DOC>
<DOCNO> 120588 </DOCNO>
The First Acoustics Peak CMBR and Cosmic Total Density


  Boomerang measured the first peak in CMBR to be at location of $l_D=196\pm
6$, which excites our strong interesting in it. A widely cited formula is
$l_D\simeq 200\Omega_T^{-0.50}$ to estimate the cosmic total density. Weinberg
shows it is not correct and should be $l_D\propto \Omega_T^{-1.58}$ near the
interest point $(\Omega_m,\Omega_\Lambda)=(0.3,0.7)$. We show further that it
should be $l_D\propto \Omega_T^{-1.43}\Omega_m^{-0.147}$ or
$\Omega_T^{-1.92}\Omega_\Lambda^{0.343}$ near the same point in the more
veracious sense if we consider the effect from the sound horizon. We draw a
contour graph for the peak location, show that the recent data favor to a
closed universe with about $\Omega_T\simeq 1.03$. If we insist on obtaining a
flat universe, a point $(0.36,0.64)$, i.e., more matter and less vacuum energy,
is still possible, which has a more right-side first peak $l_D=208$ in CMBR and
a smaller acceleration parameter $-q_0=0.10$ for the $z=0.4$ redshift SNIa.

</DOC>
<DOC>
<DOCNO> 71311 </DOCNO>
Excitation of Color Degrees of Freedom of Nuclear Matter and $J/\psi$


  In high energy nuclear collisions, the conventional Glauber model is commonly
used to evaluate the contribution to $J/\psi$ suppression originating from the
inelastic interaction with colorless bound nucleons. This requires an effective
value for the $J/\psi$-nucleon absorption cross section which is larger than
theoretically expected. On the other hand, multiple nucleon-nucleon collisions
mediated by color exchange interactions, excite their color degrees of freedom.
We investigate the importance of this effect and find that these excited states
provide a larger cross section for $J/\psi$ absorption. We conclude that the
related corrections are important to explain the effective value extrapolated
from experiment.

</DOC>
<DOC>
<DOCNO> 10128 </DOCNO>
Relation between Raman spectra and Structure of Amorphous Silicon


  In 1985, Beeman, Tsu and Thorpe established an almost linear relation between
the Raman transverse-optic (TO) peak width and the spread in mean bond angle in
a-Si. This relation is often used to estimate the latter quantity in
experiments. In the last decade, there has been significant progress in the
computer generation of sample networks of amorphous silicon. Exploiting this
progress, this manuscript presents a more accurate determination of the
relation between the TO peak width and angular spread using 1000-atom
configurations. Also investigated and quantified are the relations between the
TO peak frequency and the ratio of the intensities of the transverse-acoustic
(TA) and TO peak, both as functions of the angular spread. As this spread
decreases, the TA/TO intensity ratio decreases and the TO peak frequency
increases. These relations offer additional ways to obtain structural
information on a-Si from Raman measurements.

</DOC>
<DOC>
<DOCNO> 100954 </DOCNO>
Pieri-type formulas for the non-symmetric Jack polynomials


  In the theory of symmetric Jack polynomials the coefficients in the expansion
of the $p$th elementary symmetric function $e_p(z)$ times a Jack polynomial
expressed as a series in Jack polynomials are known explicitly. Here analogues
of this result for the non-symmetric Jack polynomials $E_\eta(z)$ are explored.
Necessary conditions for non-zero coefficients in the expansion of $e_p(z)
E_\eta(z)$ as a series in non-symmetric Jack polynomials are given. A known
expansion formula for $z_i E_\eta(z)$ is rederived by an induction procedure,
and this expansion is used to deduce the corresponding result for the expansion
of $\prod_{j=1, j\ne i}^N z_j E_\eta(z)$, and consequently the expansion of
$e_{N-1}(z) E_\eta(z)$. In the general $p$ case the coefficients for special
terms in the expansion are presented.

</DOC>
<DOC>
<DOCNO> 71628 </DOCNO>
Baryogenesis at the Electroweak Phase Transition for a SUSY Model with a


  SUSY models with a gauge singlet easily allow for a strongly first order
electroweak phase transition (EWPT). We discuss the wall profile, in particular
transitional CP violation during the EWPT. We calculate CP violating source
terms for the charginos in the WKB approximation and solve the relevant
transport equations to obtain the generated baryon asymmetry.

</DOC>
<DOC>
<DOCNO> 118390 </DOCNO>
Gamma-loud quasars: a view with BeppoSAX


  We present $Beppo$SAX observations of the $\gamma $-ray emitting quasars
0836+710, 1510-089 and 2230+114. All the objects have been detected in the PDS
up to 100 keV and have extremely flat power-law spectra above 2 keV ($\alpha
_x$=0.3--0.5). 0836+710 shows absorption higher than the galactic value and
marginal evidence for the presence of the redshifted 6.4 keV Iron line.
1510-089 shows a spectral break around 1 keV, with the low energy spectrum
steeper ($\alpha_l$=1.6) than the high energy power-law ($\alpha_h$=0.3). The
data are discussed in the light of current Inverse Compton models for the high
energy emission.

</DOC>
<DOC>
<DOCNO> 150598 </DOCNO>
Gravity Duals of Supersymmetric SU(N) x SU(N+M) Gauge Theories


  The world volume theory on N regular and M fractional D3-branes at the
conifold singularity is a non-conformal n=1 supersymmetric SU(N+M) x SU(N)
gauge theory. In previous work the Type IIB supergravity dual of this theory
was constructed to leading non-trivial order in M/N: it is the AdS_5 x T^{1,1}
background with NS-NS and R-R 2-form fields turned on. Far in the UV this dual
description was shown to reproduce the logarithmic flow of couplings found in
the field theory. In this paper we study the supersymmetric RG flow at all
scales. We introduce an ansatz for the 10-d metric and other fields and show
that the equations of motion may be derived in first order form from a simple
superpotential. This allows us to explicitly solve for the gravity dual of the
RG trajectory.

</DOC>
<DOC>
<DOCNO> 151397 </DOCNO>
Bosonic D-Branes at Finite Temperature


  We derive the finite temperature description of bosonic D-branes in the
thermo field approach. The results might be relevant to the study of thermical
properties of D-brane systems.

</DOC>
<DOC>
<DOCNO> 7995 </DOCNO>
Far-infrared excitations in a quantum antidot at finite magnetic fields


  We have investigated the far-infrared dipole modes of a quantum antidot
submitted to a perpendicularly applied magnetic field B. The ground state of
the antidot is described within local spin-density functional theory, and the
spectrum within time-dependent local spin-density functional theory. The
results are compared with those corresponding to a quantum dot of similar
electronic surface density. The method is able to reproduce two of the more
salient experimental features, namely that main bulk and edge modes have the
same circular polarization, and that the negative B dispersion edge branch
oscillates, having minima at the B values corresponding to fully occupied
Landau levels. It fails, however, to yield the unique feature of short-period
antidot lattices that the energy of the edge magnetoplasmon approaches the
cyclotron frequency for small B. The existence of anticyclotron polarized bulk
modes is discussed, and a detailed account of the dipole spin mode is
presented.

</DOC>
<DOC>
<DOCNO> 10677 </DOCNO>
On the compatibility of causality and symmetry (Comments on "Analysis of


  It is argued that there exists the only one inverse of the linear response
function $\chi$, i.e. $\chi^{-1}$, which depends symmetrically of its
spatial-times variables, see M.K. Harbola, and A. Banerjee, Phys. Rev. A {\bf
60}, 5101 (1999). Some brief comments on this consideration are presented. We
show instead, that it is possible to construct the causal inverse also. At the
same time we confirm the main statement of M.K. Harbola and A. Banerjee that in
fact there is no contradiction between the symmetry and causality.

</DOC>
<DOC>
<DOCNO> 8735 </DOCNO>
Non-Fermi Liquid Behavior in U and Ce Alloys: Criticality, Disorder,


  In this paper we provide the theoretical basis for the problem of
Griffiths-McCoy singularities close to the quantum critical point for magnetic
ordering in U and Ce intermetallics. We show that the competition between Kondo
effect and RKKY interaction can be expressed in Hamiltonian form and the
dilution effect due to alloying leads to a quantum percolation problem driven
by the number of magnetically compensated moments. We argue that the exhaustion
paradox proposed by Nozi\`eres is explained when the RKKY interaction is taken
into account. We revisited the one impurity and two impurity Kondo problem and
showed that in the presence of particle-hole symmetry breaking operators the
system flows to a line of fixed points characterized by coherent motion of the
spins. This leads to a {\it cluster Kondo effect}. We calculate explicitly from
the microscopic Hamiltonian the parameters which appear in all the response
functions. We show that there is a maximum number $N_c$ of spins in the
clusters such that above this number tunneling ceases to occur. These effects
lead to a distribution of cluster Kondo temperatures which vanishes for finite
clusters and therefore leads to strong magnetic response. From these results we
propose a {\it dissipative quantum droplet model} which describes the critical
behavior of metallic magnetic systems. This model predicts that in the
paramagnetic phase there is a crossover temperature $T^*$ above which
Griffiths-McCoy like singularities with power law behavior. Below $T^*$,
however, a new regime dominated by dissipation occurs with stronger
divergences. We estimate that $T^*$ is exponentially small with $N_c$.

</DOC>
<DOC>
<DOCNO> 102656 </DOCNO>
The Diameter of Long-Range Percolation Clusters on Finite Cycles


  Bounds for the diameter and for the expansion of long-range percolation
clusters on the cycle $\Z / N\Z$ are given.

</DOC>
<DOC>
<DOCNO> 84285 </DOCNO>
On the triviality of certain non-Riemannian models of gravitation


  We prove in the Tucker-Wang approach to non-Riemannian Gravity that a general
homogeneous Lagrangian density in the general connection with order of
homogeneity of at least two, gives no contribution to the generalised Einstein
equations. Using this result other important cases are also considered.

</DOC>
<DOC>
<DOCNO> 178958 </DOCNO>
Statistical Multifragmentation in Thermodynamic Limit


  An exact analytical solution of the statistical multifragmentation model is
found in thermodynamic limit. The model exhibits a 1-st order phase transition
of the liquid-gas type. The mixed phase region of the phase diagram, where the
gas of nuclear fragments coexists with the infinite liquid condensate, is
unambiguously identified. The peculiar thermodynamic properties of the model
near the boundary between the mixed phase and the pure gaseous phase are
studied. The results for the caloric curve and specific heat are presented and
a physical picture of the nuclear liquid-gas phase transition is clarified.

</DOC>
<DOC>
<DOCNO> 71138 </DOCNO>
Weak and Electromagnetic Interactions of Hyperons: a Chiral Approach


  A range of issues in the field of weak and electromagnetic interactions of
hyperons is presented from the perspective of (broken) chiral symmetry,
together with an assessment of where important challenges remain.

</DOC>
<DOC>
<DOCNO> 69982 </DOCNO>
Strong Isospin Breaking in CP-even and CP-odd K -> pi pi Decays


  Complete next-to-leading (chiral) order (NLO) expressions for the strong
isospin-breaking (IB) contributions in K -> pi pi are used to discuss (1) for
CP-even, the impact on the magnitude of the Delta I=1/2 Rule, and (2) for
CP-odd, the strong IB correction, Omega_st, for the gluonic penguin
contribution to epsilon'/epsilon, with particular emphasis on the strong
low-energy constant (LEC) and loop contributions, numerical values for which
are model-independent at NLO.

</DOC>
<DOC>
<DOCNO> 8032 </DOCNO>
Two-channel Kondo model as a generalized one-dimensional inverse square


  Majorana fermion representations of the algebra associated with spin, charge,
and flavor currents have been used to transform the two-channel Kondo
Hamiltonian. Using a path integral formulation, we derive a reduced effective
action with long-range impurity spin-spin interactions at different imaginary
times. In the semiclassical limit, it is equivalent to a one-dimensional
Heisenberg spin chain with two-spin, three-spin, etc. long-range interactions,
as a generalization of the inverse-square long-range Haldane-Shastry spin
model. In this representation the elementary excitations are "semions", and the
non-Fermi-liquid low-energy properties of the two-channel Kondo model are
recovered.

</DOC>
<DOC>
<DOCNO> 102741 </DOCNO>
Descent Numbers and Major Indices for the Hyperoctahedral Group


  We introduce and study three new statistics on the hyperoctahedral group
$B_{n}$, and show that they give two generalizations of Carlitz's identity for
the descent number and major index over $S_{n}$. This answers a question posed
by Foata.

</DOC>
<DOC>
<DOCNO> 119648 </DOCNO>
MHD Stellar and Disk Winds: Application to Planetary Nebulae


  MHD winds can emanate from both stars and surrounding accretion disks. It is
of interest to know how much wind power is available and which (if either) of
the two rotators dominates that power. We investigate this in the context of
multi-polar planetary nebulae (PNe) and proto-planetary nebulae (PPNe), for
which recent observations have revealed the need for a wind power source in
excess of that available from radiation driving, and a possible need for
magnetic shaping. We calculate the MHD wind power from a coupled disk and star,
where the former results from binary disruption. The resulting wind powers
depend only on the accretion rate and stellar properties. We find that if the
stellar envelope were initially slowly rotating, the disk wind would dominate
throughout the evolution. If the envelope of the star were rapidly rotating,
the stellar wind could initially be of comparable power to the disk wind until
the stellar wind carries away the star's angular momentum. Since an initially
rapidly rotating star can have its spin and magnetic axes misaligned to the
disk, multi-polar outflows can result from this disk wind system. For times
greater than a spin-down time, the post-AGB stellar wind is slaved to the disk
for both slow and rapid initial spin cases and the disk wind luminosity
dominates. We find a reasonably large parameter space where a hybrid star+disk
MHD driven wind is plausible and where both or either can account for PPNe and
PNe powers. We also speculate on the morphologies which may emerge from the
coupled system. The coupled winds might help explain the shapes of a number of
remarkable multi-shell or multi-polar nebulae. Magnetic activity such as X-ray
flares may be associated with the both central star and the disk and would be a
valuable diagnostic for the dynamical role of MHD processes in PNe.

</DOC>
<DOC>
<DOCNO> 13438 </DOCNO>
Thermodynamic Bethe ansatz for generalized extensive statistics


  We investigate properties of the entropy density related to a generalized
extensive statistics and derive the thermodynamic Bethe ansatz equation for a
system of relativistic particles obeying such a statistics. We investigate the
conformal limit of such a system. We also derive a generalized Y-system. The
Gentile intermediate statistics and the statistics of gamma-ons are considered
in detail. In particular, we observe that certain thermodynamic quantities for
the Gentile statistics majorize those for the Haldane-Wu statistics.
Specifically, for the effective central charges related to affine Toda models
we obtain nontrivial inequalities in terms of dilogarithms.

</DOC>
<DOC>
<DOCNO> 9129 </DOCNO>
Phenomenological glass model for vibratory granular compaction


  A model for weakly excited granular media is derived by combining the free
volume argument of Nowak et al. [Phys. Rev. E 57, 1971 (1998)] and the
phenomenological model for supercooled liquids of Adam and Gibbs [J. Chem.
Phys. 43, 139 (1965)]. This is made possible by relating the granular
excitation parameter \Gamma, defined as the peak acceleration of the driving
pulse scaled by gravity, to a temperature-like parameter \eta(\Gamma). The
resulting master equation is formally identical to that of Bouchaud's trap
model for glasses [J. Phys. I 2, 1705 (1992)]. Analytic and simulation results
are shown to compare favourably with a range of known experimental behaviour.
This includes the logarithmic densification and power spectrum of fluctuations
under constant \eta, the annealing curve when \eta is varied cyclically in
time, and memory effects observed for a discontinuous shift in \eta. Finally,
we discuss the physical interpretation of the model parameters and suggest
further experiments for this class of systems.

</DOC>
<DOC>
<DOCNO> 68651 </DOCNO>
Duality, Equivalence, Mass and The Quest For The Vacuum


  I contemplate the possibility that the mismatch between the maximally
symmetric point (the free fermionic point) and the strictly self-dual point in
the Narain moduli space plays a role in the string vacuum selection. The role
of self-duality in the recent formulation of quantum mechanics from an
equivalence postulate, and the new perspective that it offers on the
foundations of quantum gravity and the origin of mass, are discussed.

</DOC>
<DOC>
<DOCNO> 118481 </DOCNO>
Narrow Line Seyfert 1 Galaxies and the Evolution of Galaxies & Active


  Narrow Line Seyfert 1 galaxies (NLS1s) are intriguing due to their continuum
as well as emission line properties. The observed peculiar properties of the
NLS1s are believed to be due to accretion rate close to Eddington limit. As a
consequence, for a given luminosity,
 NLS1s have smaller black hole (BH) masses compared to normal Seyfert galaxies.
Here we argue that NLS1s might be Seyfert galaxies in their early stage of
evolution and as such may be low redshift, low luminosity analogues of high
redshift quasars. We propose that NLS1s may reside in rejuvenated, gas rich
galaxies. We also argue in favor of collisional ionization for production of
FeII in active galactic nuclei (AGN).

</DOC>
<DOC>
<DOCNO> 118283 </DOCNO>
The superbubble model for Li, Be and B production and Galactic evolution


  We show that the available constraints relating to $^{6}$LiBeB Galactic
evolution can be accounted for by the so-called superbubble model, according to
which particles are efficiently accelerated inside superbubbles out of a
mixture of supernova ejecta and ambient interstellar medium. The corresponding
energy spectrum is required to be flat at low energy (in E^-1 below 500 MeV/n,
say), as expected from Bykov's acceleration mechanism. The only free parameter
is also found to have the value expected from standard SB dynamical evolution
models. Our model predicts a slope 1 (primary) and a slope 2 (secondary)
behaviour at respectively low and high metallicity, with all intermediate
slopes achieved in the transition region, between 10^-2 and 10^-1 Z_sol.

</DOC>
<DOC>
<DOCNO> 13191 </DOCNO>
Sandpiles and absorbing-state phase transitions: recent results and open


  We review some recent results on the relations between sandpiles and a class
of absorbing state phase transitions. We use the concept of fixed energy
sandpiles (FES), in which external driving and dissipation are absent.
 FES are shown to exhibit an absorbing state transition with critical
properties coinciding with those of the corresponding sandpile model. We
propose a set of Langevin equations capturing the relevant features of this
transition. These equations characterize the universality class of systems with
an infinite number of absorbing states and a static conserved field coupled to
the order parameter. Different models in this class are identified, and strong
evidence is presented showing that the Manna sandpile, as well as some other
stochastic sandpiles, belong in this universality class. Finally some open
problems and questions are discussed.

</DOC>
<DOC>
<DOCNO> 85417 </DOCNO>
Gravitational Wavetrains in the Quasi-Equilibrium Approximation: A Model


  A quasi-equilibrium (QE) computational scheme was recently developed in
general relativity to calculate the complete gravitational wavetrain emitted
during the inspiral phase of compact binaries. The QE method exploits the fact
that the the gravitational radiation inspiral timescale is much longer than the
orbital period everywhere outside the ISCO. Here we demonstrate the validity
and advantages of the QE scheme by solving a model problem in relativistic
scalar gravitation theory. By adopting scalar gravitation, we are able to
numerically track without approximation the damping of a simple, quasi-periodic
radiating system (an oscillating spherical matter shell) to final equilibrium,
and then use the exact numerical results to calibrate the QE approximation
method. In particular, we calculate the emitted gravitational wavetrain three
different ways: by integrating the exact coupled dynamical field and matter
equations, by using the scalar-wave monopole approximation formula
(corresponding to the quadrupole formula in general relativity), and by
adopting the QE scheme. We find that the monopole formula works well for weak
field cases, but fails when the fields become even moderately strong. By
contrast, the QE scheme remains quite reliable for moderately strong fields,
and begins to breakdown only for ultra-strong fields. The QE scheme thus
provides a promising technique to construct the complete wavetrain from binary
inspiral outside the ISCO, where the gravitational fields are strong, but where
the computational resources required to follow the system for more than a few
orbits by direct numerical integration of the exact equations are prohibitive.

</DOC>
<DOC>
<DOCNO> 151178 </DOCNO>
D-brane gauge theories from toric singularities of the form $C^3/\Gamma$


  We discuss examples of D-branes probing toric singularities, and the
computation of their world-volume gauge theories from the geometric data of the
singularities. We consider several such examples of D-branes on partial
resolutions of the orbifolds ${\bf C^3/Z_2\times Z_2}$,${\bf C^3/Z_2\times
Z_3}$ and ${\bf C^4/Z_2\times Z_2 \times Z_2}$.

</DOC>
<DOC>
<DOCNO> 14094 </DOCNO>
The magnetic ordering in the mixed valence compound beta-Na0.33V2O5


  The low-temperature electron spin resonance (ESR) spectra and the static
magnetization data obtained for the stoichiometric single crystals of
$\beta$-Na$_{0.33}$V$_2$O$_5$ indicate that this quasi-one-dimensional mixed
valence (V4+/V5+) compound demonstrates at $T_N=22$ K the phase transition into
the canted antiferromagnetically ordered state. The spontaneous magnetization
of $3.4\times 10^{-3}$ $\mu_B$ per V$^{4+}$ ion was found to be oriented along
the two-fold $b$ axis of the monoclinic structure, the vector of
antiferromagnetism is aligned with the $a$ axis and the Dzyaloshinsky vector is
parallel to the $c$-axis. The experimental data were successfully described in
the frame of the macroscopic spin dynamics and the following values for the
macroscopic parameters of the spin system were obtained: the Dzyaloshinsky
field $H_D=6$ kOe, the energy gaps of two branches of the spin wave spectrum
$\Delta_1=48$ GHz and $\Delta_2=24$ GHz.

</DOC>
<DOC>
<DOCNO> 116628 </DOCNO>
Damage of cellular material under simultaneous application of pressure


  Influence of pulsed electric field (PEF) simultaneous to pressure treatment
on moisture expression from fine-cut cellular raw material has been
investigated. Dependencies of specific conductivity $\sigma$, liquid yield $Y$,
instantaneous flow rate $v$ and qualitative juice characteristics at different
modes of PEF treatment are discussed. Three main consolidation phases were
observed in a case of mechanical expression. A unified approach is proposed for
liquid yield data analysis allowing to reduce the data scattering caused by
differences in the quality of samples. Simultaneous application of pressure and
PEF treatment allows to reveal a passive form of electrical damage. Pressure
provokes the damage of defected cells, enhances diffusion migration of moisture
in porous cellular material and depresses the cell resealing processes. PEF
application at a moment when a sample specific electrical conductivity reaches
minimum and pressure achieves its constant value seemed to be the most optimal.

</DOC>
<DOC>
<DOCNO> 178823 </DOCNO>
Neutral weak currents in pion electroproduction on the nucleon


  Parity violating asymmetry in inclusive scattering of longitudinally
polarized electrons by unpolarized protons with $\pi^0$ or $\pi^+$ meson
production, is calculated as a function of the momentum transfer squared $Q^2$
and the total energy $W$ of the $\pi N$-system. This asymmetry, which is
induced by the interference of the one-photon exchange amplitude with the
parity-odd part of the $Z^0$-exchange amplitude, is calculated for the
$\gamma^*(Z^*)+p\to N+\pi$ processes ($\gamma^*$ is a virtual photon and $Z^*$
a virtual Z-boson) considering the $\Delta$-contribution in the $s-$channel,
the standard Born contributions and vector meson ($\rho$ and $\omega$)
exchanges in the $t-$channel. Taking into account the known isotopic properties
of the hadron electromagnetic and neutral currents, we show that the P-odd term
is the sum of two contributions. The main term is model independent and it can
be calculated exactly in terms of fundamental constants. It is found to be
linear in $Q^2$. The second term is a relatively small correction which is
determined by the isoscalar component of the electromagnetic current. Near
threshold and in the $\Delta$-region, this isoscalar part is much smaller (in
absolute value) than the isovector one: its contribution to the asymmetry
depend on the polarization state (longitudinal or transverse) of the virtual
photon.

</DOC>
<DOC>
<DOCNO> 85429 </DOCNO>
Generating spherically symmetric static perfect fluid solutions


  By a choice of new variables the pressure isotropy condition for spherically
symmetric static perfect fluid spacetimes can be made a quadratic algebraic
equation in one of the two functions appearing in it. Using the other variable
as a generating function, the pressure and the density of the fluid can be
expressed algebraically by the function and its derivatives. One of the
functions in the metric can also be expressed similarly, but to obtain the
other function, related to the redshift factor, one has to perform an integral.
Conditions on the generating function ensuring regularity and physicality near
the center are investiagted. Two everywhere physically well behaving example
solutions are generated, one representing a compact fluid body with a zero
pressure surface, the other an infinite sphere.

</DOC>
<DOC>
<DOCNO> 169592 </DOCNO>
Freezing Light via hot gases


  We prove that it is possible to freeze a light pulse (i.e., to bring it to a
full stop) or even to make its group velocity negative in a coherently driven
Doppler broadened atomic medium via electromagnetically induced transparency
(EIT). This remarkable phenomenon of the ultra-slow EIT polariton is based on
the spatial dispersion of the refraction index $n(\w,k)$, i.e., its wavenumber
dependence, which is due to atomic motion and provides a negative contribution
to the group velocity. This is related to, but qualitatively different from,
the recently observed light slowing caused by large temporal (frequency)
dispersion.

</DOC>
<DOC>
<DOCNO> 150590 </DOCNO>
DeSitter entropy, quantum entanglement and ADS/CFT


  A deSitter brane-world bounding regions of anti-deSitter space has a
macroscopic entropy given by one-quarter the area of the observer horizon. A
proposed variant of the AdS/CFT correspondence gives a dual description of this
cosmology as conformal field theory coupled to gravity in deSitter space. In
the case of two-dimensional deSitter space this provides a microscopic
derivation of the entropy, including the one-quarter, as quantum entanglement
of the conformal field theory across the horizon.

</DOC>
<DOC>
<DOCNO> 119632 </DOCNO>
The Infrared Jet In 3C66B


  We present images of infrared emission from the radio jet in 3C66B. Data at
three wavelengths (4.5, 6.75 and 14.5 microns) were obtained using the Infrared
Space Observatory. The 6.75 micron image clearly shows an extension aligned
with the radio structure. The jet was also detected in the 14.5 micron image,
but not at 4.5 micron. The radio-infrared-optical spectrum of the jet can be
interpreted as synchrotron emission from a population of electrons with a
high-energy break of 4e11 eV. We place upper limits on the IR flux from the
radio counter-jet. A symmetrical, relativistically beamed twin-jet structure is
consistent with our results if the jets consist of multiple components.

</DOC>
<DOC>
<DOCNO> 121881 </DOCNO>
Molecular QSO Absorption Line Systems


  We review observations of molecular absorption line systems at high redshift
toward red quasars and gravitational lenses.

</DOC>
<DOC>
<DOCNO> 11055 </DOCNO>
Driven vortices in confined geometry: the Corbino disk


  The fabrication of artificial pinning structures allows a new generation of
experiments which can probe the properties of vortex arrays by forcing them to
flow in confined geometries. We discuss the theoretical analysis of such
experiments in both flux liquids and flux solids, focusing on the Corbino disk
geometry. In the liquid, these experiments can probe the critical behavior near
a continuous liquid-glass transition. In the solid, they probe directly the
onset of plasticity.

</DOC>
<DOC>
<DOCNO> 170633 </DOCNO>
On the fidelity of two pure states


  The fidelity of two pure states (also known as transition probability) is a
symmetric function of two operators, and well-founded operationally as an event
probability in a certain preparation-test pair. Motivated by the idea that the
fidelity is the continuous quantum extension of the combinatorial equality
function, we enquire whether there exists a symmetric operational way of
obtaining the fidelity. It is shown that this is impossible. Finally, we
discuss the optimal universal approximation by a quantum operation.

</DOC>
<DOC>
<DOCNO> 151348 </DOCNO>
Open and Closed Universes in Brane-World Cosmology


  We find two types [called (S) and (A)] of new vacuum solutions of open, flat,
and closed universes which are inflating in the brane-world scenario. We show
that the warp factor of the stabilized metric is universal for the three
different kinds of universes. For (S) type solution, we show that one
positive-tension brane universe solution is admitted as well as two positive
tension brane solution even if we consider the vacuum solution. For (A) type
solution, we find that the inflating bulk solutions have black hole like
regions and that the full extended space is the R-S solution.

</DOC>
<DOC>
<DOCNO> 71644 </DOCNO>
Electrogenesis in a scalar field dominated epoch


  In this talk I discuss models in which a homogeneous scalar field is used to
modify standard cosmology above the nucleosynthesis scale to provide an
explanation for the observed matter-antimatter asymmetry of the Universe.

</DOC>
<DOC>
<DOCNO> 11211 </DOCNO>
Critical Dynamics of Gelation


  Shear relaxation and dynamic density fluctuations are studied within a Rouse
model, generalized to include the effects of permanent random crosslinks. We
derive an exact correspondence between the static shear viscosity and the
resistance of a random resistor network. This relation allows us to compute the
static shear viscosity exactly for uncorrelated crosslinks. For more general
percolation models, which are amenable to a scaling description, it yields the
scaling relation $ k=\phi-\beta$ for the critical exponent of the shear
viscosity. Here $\beta$ is the thermal exponent for the gel fraction and $\phi$
is the crossover exponent of the resistor network. The results on the shear
viscosity are also used in deriving upper and lower bounds on the incoherent
scattering function in the long-time limit, thereby corroborating previous
results.

</DOC>
<DOC>
<DOCNO> 101391 </DOCNO>
Discrete series of representations for Uq(sl(2,R))


  A possible generalization of the method of orbits to SLq(2,R) is discussed.

</DOC>
<DOC>
<DOCNO> 150690 </DOCNO>
The role of complex structures in w-symmetry


  In a symplectic framework, the infinitesimal action of symplectomorphisms
together with suitable reparametrizations of the two dimensional complex base
space generate some type of W-algebras. It turns out that complex structures
parametrized by Beltrami differentials play an important role in this context.
The construction parallels very closely two dimensional Lagrangian conformal
models where Beltrami differentials are fundamental.

</DOC>
<DOC>
<DOCNO> 71926 </DOCNO>
Report of the Working Group on Goldstone Bosons


  An overview is presented of the talks in the working group on Goldstone
Bosons. Topics touched on are CP-violation in the Kaon system, rare Kaon
decays, $\pi\pi$-scattering, $\phi$-meson decays, scalar mesons, form-factors
and polarizabilities, $\eta$-decays, chiral symmetry breaking, connections with
QCD at short-distances and effective theories for electroweak physics.

</DOC>
<DOC>
<DOCNO> 169964 </DOCNO>
Quantum Kolmogorov Complexity


  In this paper we give a definition for quantum Kolmogorov complexity. In the
classical setting, the Kolmogorov complexity of a string is the length of the
shortest program that can produce this string as its output. It is a measure of
the amount of innate randomness (or information) contained in the string.
  We define the quantum Kolmogorov complexity of a qubit string as the length
of the shortest quantum input to a universal quantum Turing machine that
produces the initial qubit string with high fidelity. The definition of Vitanyi
(Proceedings of the 15th IEEE Annual Conference on Computational Complexity,
2000) measures the amount of classical information, whereas we consider the
amount of quantum information in a qubit string. We argue that our definition
is natural and is an accurate representation of the amount of quantum
information contained in a quantum state.

</DOC>
<DOC>
<DOCNO> 12314 </DOCNO>
The broad Brillouin doublets and central peak of KTaO_3


  The incipient ferroelectric KTaO3 presents low-T Brillouin spectra
anomalies,e.g. a broad central peak (CP), and some additional Brillouin
doublets (BD), whose origin is interpreted in terms of phonon-density
fluctuation processes. A parameterisation from new extensive high-resolution
neutron-scattering measurements is used to show that hydrodynamic second sound
from high damping (compared to BD frequency) TA phonons may exist in the
crystal. Furthermore, low damping thermal phonons may scatter light through
two-phonon difference processes and appear on the Brillouin spectra either as a
sharp or a broader BD, depending on the phonon damping and group velocity . The
comparison between computed anisotropies and experimental measurements favours
the second process.

</DOC>
<DOC>
<DOCNO> 12712 </DOCNO>
Exciton-exciton interaction in quantum wells. Optical properties and


  The gas of interacting excitons in quantum wells is studied. We obtain the
Hamiltonian of this gas by the projection of the electron-hole plasma
Hamiltonian to exciton states and an expansion in a small density. Matrix
elements of the exciton Hamiltonian are rather sensitive to the geometry of the
heterostructure. The mean field approximation of the exciton Hamiltonian gives
the blue shift and spin splitting of the exciton luminescence lines. We also
write down the Boltzmann equation for excitons and estimate the energy and spin
relaxation time resulting from the exciton-exciton scattering. Making use of
these calculations we succeeded to explain some recent experimental results
which have not been explained so far.

</DOC>
<DOC>
<DOCNO> 10022 </DOCNO>
Statistical properties of the 2D attached Rouse chain


  We study various dynamical properties (winding angles, areas) of a set of
harmonically bound Brownian particles (monomers), one endpoint of this chain
being kept fixed at the origin 0. In particular, we show that, for long times
t, the areas {A_i} enclosed by the monomers scale like t^{1/2}, with correlated
gaussian distributions. This is at variance with the winding angles {\theta_i}
around fixed points that scale like t and are distributed according to
independent Cauchy laws.

</DOC>
<DOC>
<DOCNO> 68861 </DOCNO>
A perturbative treatment of double gluon exchange in gamma*-proton DIS


  A new model for the exchange of two gluons between the virtual photon and the
proton, in non-diffractive deeply inelastic electron-proton scattering, is
developed and studied. This model relies on a perturbative calculation,
previously applied to diffraction, and a general result from Regge theory. As a
first application of the model, we study corrections to the momentum transfer
to the quark-anti-quark pair, at the photon-vertex. We find a significant
enhancement of the cross-section at ~Q^2 momentum transfers, and large negative
corrections for small momentum transfers. The implication of this result for
jet-distributions measured at HERA, is discussed.

</DOC>
<DOC>
<DOCNO> 69918 </DOCNO>
Perturbative Renormalization of Weak-Hamiltonian Four-Fermion Operators


  The renormalization of the most general dimension-six four-fermion operators
without power subtractions is studied at one loop in lattice perturbation
theory using overlap fermions. As expected, operators with different chirality
do not mix among themselves and parity-conserving and parity-violating
multiplets renormalize in the same way. The renormalization constants of
unimproved and improved operators are also the same. These mixing factors are
necessary to determine physical matrix elements relevant to many
phenomenological applications of weak interactions. The most important are the
K0-K0bar and B0-B0bar mixings in the Standard Model and beyond, the Delta I
=1/2 rule and epsilon'/epsilon.

</DOC>
<DOC>
<DOCNO> 152595 </DOCNO>
World Volume Action for Fractional Branes


  We study the world volume action of fractional Dp-branes of type IIA string
theory compactified on the orbifold T^4/Z_2. The geometric relation between
these branes and wrapped branes is investigated using conformal techniques. In
particular we examine in detail various scattering amplitudes and find that the
leading low-energy interactions are consistent with the boundary action derived
geometrically.

</DOC>
<DOC>
<DOCNO> 69439 </DOCNO>
Effects of The Initial Hadron in $B\to J/\psi+X$


  In the framework of HQET inclusive decays of b-flavored hadrons can be
handled as decays of the free b-quark approximately. We analyse the correction
to this approximation for the inclusive decays into a polarized $J/\psi$,the
correction is characterized by two matrix elements defined in HQET. For the
$J/\psi$ we use NRQCD to parameterize the formation of the $c\bar c$ pair into
$J/\psi$. Numerically the correction is remarkably large, it can be at the
level of 30% and it is mainly due to the Fermi-motion of the $b$-quark. With
this correction we give a new determination for combinations of two NRQCD
matrix elements.

</DOC>
<DOC>
<DOCNO> 170008 </DOCNO>
Broadcasting of entanglement in three-particle GHZ state via quantum


  We introduce entanglement measures to describe entanglement in a
three-particle system and apply it to studying broadcasting of entanglement in
three-particle GHZ state. We show that entanglement of three-qubit GHZ state
can be partially broadcasted with the help of local or non-local copying
processes. It is found that non-local cloning is much more efficient than local
cloning for the broadcasting of entanglement.

</DOC>
<DOC>
<DOCNO> 102498 </DOCNO>
Noncommutative Manifolds the Instanton Algebra and Isospectral


  We give new examples of noncommutative manifolds that are less standard than
the NC-torus or Moyal deformations of $\Rb^n$. They arise naturally from basic
considerations of noncommutative differential topology and have non-trivial
global features. The new examples include the instanton algebra and the
NC-4-spheres $S^4_{\theta}$. The noncommutative algebras $\Ac=C^{\ify}
(S^{4}_{\theta})$ of functions on NC-spheres are solutions to the vanishing, $
{\rm ch}_j (e) = 0, j < 2 $, of the Chern character in the cyclic homology of
$\Ac$ of an idempotent $e \in M_4 (\Ac), e^2 = e, e = e^*$. The universal
noncommutative space defined by this equation is a noncommutative Grassmanian
defined by very non trivial cubic relations. This space ${\rm Gr}$ contains the
suspension of a NC-3-sphere intimately related to quantum group deformations
${\rm SU}_q (2)$ of ${\rm SU} (2)$ but for unusual values (complex values of
modulus one) of the parameter $q$ of $q$-analogues, $q=\exp (2\pi i \t)$. We
then construct the noncommutative geometry of $S_{\t}^4$ as given by a spectral
triple $(\Ac, \Hc, D)$ and check all axioms of noncommutative manifolds. The
Dirac operator $D$ on the noncommutative 4-spheres $S_{\t}^4$ gives a solution
to the basic quartic equation defining the `volume form' $ < (e - {1/2})
[D,e]^4 > = \g_5$, where $<$ is the projection on the commutant of $4 \ts 4$
matrices. Finally, we show that any compact Riemannian spin manifold whose
isometry group has rank $r \geq 2$ admits isospectral deformations to
noncommutative geometries.

</DOC>
<DOC>
<DOCNO> 69246 </DOCNO>
epsilon'/epsilon in the Chiral Limit


  The $K\to\pi\pi$ system is analyzed in the chiral limit within the Standard
Model. We discuss how to connect the short-distance running in the $|\Delta
S|=1$ case to the matrix-elements calculated in a low-energy approximation in a
scheme-independent fashion. We calculate this correction and the resulting
Wilson Coefficients. The matrix elements are calculated to next-to-leading
order in the $1/N_c$ expansion and combined with the Wilson coefficients to
calculate the two isospin amplitudes and $\epsilon_K^\prime$. The $\Delta
I=1/2$ rule is reproduced within expected errors and we obtain a substantially
larger value for $\epsilon_K^\prime/\epsilon_K$ than most other analysises. We
discuss the reasons for this difference. We also suggest that the $X$-boson
method is an option for lattice QCD calculations.

</DOC>
<DOC>
<DOCNO> 100624 </DOCNO>
Class numbers of orders in cubic fields


  We give an asymptotic formula for class numbers of orders in cubic number
fields.

</DOC>
<DOC>
<DOCNO> 178671 </DOCNO>
Microcanonical Lattice Gas Model for Nuclear Disassembly


  Microcanonical calculations are no more difficult to implement than canonical
calculations in the Lattice Gas Model. We report calculations for a few
observables where we compare microcanonical model results with canonical model
results.

</DOC>
<DOC>
<DOCNO> 69362 </DOCNO>
The status of NLL BFKL


  This talk summarises the current status of the NLL corrections to BFKL
physics and discusses the question of small-x factorisation.

</DOC>
<DOC>
<DOCNO> 100225 </DOCNO>
Semi-Bounded Restrictions of Dirac Type Operators and the Unique


  Let M be a connected Riemannian manifold and let D be a Dirac type operator
acting on smooth compactly supported sections in a Hermitian vector bundle over
M. Suppose D has a self-adjoint extension A in the Hilbert space of
square-integrable sections. We show that any $L^2$-section $\phi$ contained in
a closed A-invariant subspace onto which the restriction of A is semi-bounded
has the unique continuation property: if $\phi$ vanishes on a non-empty open
subset of M, then it vanishes on all of M.

</DOC>
<DOC>
<DOCNO> 7965 </DOCNO>
"Thermometers" of Speculative Frenzy


  Establishing unambiguously the existence of speculative bubbles is an
on-going controversy complicated by the need of defining a model of fundamental
prices. Here, we present a novel empirical method which bypasses all the
difficulties of the previous approaches by monitoring external indicators of an
anomalously growing interest in the public at times of bubbles. From the
definition of a bubble as a self-fulfilling reinforcing price change, we
identify indicators of a possible self-reinforcing imitation between agents in
the market. We show that during the build-up phase of a bubble, there is a
growing interest in the public for the commodity in question, whether it
consists in stocks, diamonds or coins. That interest can be estimated through
different indicators: increase in the number of books published on the topic,
increase in the subscriptions to specialized journals. Moreover, the well-known
empirical rule according to which the volume of sales is growing during a bull
market finds a natural interpretation in this framework: sales increases in
fact reveal and pinpoint the progress of the bubble's diffusion throughout
society. We also present a simple model of rational expectation which maps
exactly onto the Ising model on a random graph. The indicators are then
interpreted as ``thermometers'', measuring the balance between idiosyncratic
information (noise temperature) and imitation (coupling) strength. In this
context, bubbles are interpreted as low or critical temperature phases, where
the imitation strength carries market prices up essentially independently of
fundamentals. Contrary to the naive conception of a bubble and a crash as times
of disorder, on the contrary, we show that bubbles and crashes are times where
the concensus is too strong.

</DOC>
<DOC>
<DOCNO> 85615 </DOCNO>
Characterizing exact solutions from asymptotic physical concepts


  We contribute to the subject of the physical interpretation of exact
solutions by characterizing them through a systematic study in terms of
unambiguous physical concepts coming from systems in linearized gravity. We use
the physical meaning of the leading order behavior of the Weyl spinor
components $\Psi_0^0$, $\Psi_1^0$ and $\Psi_2^0$ and of the Maxwell spinor
components $\phi_0^0$ and $\phi_1^0$ and integrate from future null infinity
inwards the exact field equations. In this way it is assigned an unambiguous
physical meaning to exact solutions. We indicate a method to generalize the
procedure to radiating spacetimes.

</DOC>
<DOC>
<DOCNO> 12088 </DOCNO>
Intermittent Switching between Potential Flow and Turbulence in


  Superfluid flow around an oscillating microsphere is investigated at
temperatures down to 25 mK. Stable laminar flow below a critical velocity and
turbulence at large drives are found to be separated below 0.5 K by an
intermediate range of driving forces where the flow is unstable, intermittently
switching between laminar and turbulent phases. We have recorded time series of
this switching phenomenon and have made a statistical analysis of the switching
probability. The mean lifetime of the turbulent phases grows with increasing
drive and becomes infinite at a critical value. Stability of the laminar phases
above the critical velocity is limited by natural background radioactivity or
cosmic rays.

</DOC>
<DOC>
<DOCNO> 102546 </DOCNO>
Orthonormal bases of polynomials in one complex variable


  Let a sequence $(P_n)$ of polynomials in one complex variable satisfy a
recurre ce relation with length growing slowlier than linearly. It is shown
that $(P_n) $ is an orthonormal basis in $L^2_{\mu}$ for some measure $\mu$ on
$\C$, if and o ly if the recurrence is a $3-$term relation with special
coefficients. The supp rt of $\mu$ lies on a straight line. This result is
achieved by the analysis of a formally normal irreducible Hessenberg operator
with only finitely many nonzero entries in every row. It generalizes the
classical Favard's Theorem and the Representation Theorem.

</DOC>
<DOC>
<DOCNO> 170413 </DOCNO>
Performance of a deterministic source of entangled photonic qubits


  We study the possible limitations and sources of decoherence in the scheme
for the deterministic generation of polarization-entangled photons, recently
proposed by Gheri et al. [K. M. Gheri et al., Phys. Rev. A 58, R2627 (1998)],
based on an appropriately driven single atom trapped within an optical cavity.
We consider in particular the effects of laser intensity fluctuations, photon
losses, and atomic motion.

</DOC>
<DOC>
<DOCNO> 85472 </DOCNO>
Searching for continuous gravitational wave sources in binary systems


  We consider the problem of searching for continuous gravitational wave
sources orbiting a companion object. This issue is of particular interest
because the LMXB's, and among them Sco X-1, might be marginally detectable with
2 years coherent observation time by the Earth-based laser interferometers
expected to come on line by 2002, and clearly observable by the second
generation of detectors. Moreover, several radio pulsars, which could be deemed
to be CW sources, are found to orbit a companion star or planet, and the
LIGO/VIRGO/GEO network plans to continuously monitor such systems. We estimate
the computational costs for a search launched over the additional five
parameters describing generic elliptical orbits using match filtering
techniques. These techniques provide the optimal signal-to-noise ratio and also
a very clear and transparent theoretical framework. We provide ready-to-use
analytical expressions for the number of templates required to carry out the
searches in the astrophysically relevant regions of the parameter space, and
how the computational cost scales with the ranges of the parameters. We also
determine the critical accuracy to which a particular parameter must be known,
so that no search is needed for it. In order to disentangle the computational
burden involved in the orbital motion of the CW source, from the other source
parameters (position in the sky and spin-down), and reduce the complexity of
the analysis, we assume that the source is monochromatic and its location in
the sky is exactly known. The orbital elements, on the other hand, are either
assumed to be completely unknown or only partly known. We apply our theoretical
analysis to Sco X-1 and the neutron stars with binary companions which are
listed in the radio pulsar catalogue.

</DOC>
<DOC>
<DOCNO> 83129 </DOCNO>
Declarative Representation of Revision Strategies


  In this paper we introduce a nonmonotonic framework for belief revision in
which reasoning about the reliability of different pieces of information based
on meta-knowledge about the information is possible, and where revision
strategies can be described declaratively. The approach is based on a
Poole-style system for default reasoning in which entrenchment information is
represented in the logical language. A notion of inference based on the least
fixed point of a monotone operator is used to make sure that all theories
possess a consistent set of conclusions.

</DOC>
<DOC>
<DOCNO> 100005 </DOCNO>
Solving the $\dibar$-Equation in Thin Tubes % and Applications to


  We construct a family of integral kernels for solving the $\dibar$-equation
with $\cC^k$ and H\"older estimates in thin tubes around totally real
submanifolds in $\C^n$ (theorems 1.1 and 3.1). Combining this with the proof of
a theorem of Serre we solve the $d$-equation with estimates for holomorphic
forms in such tubes (theorem 5.1). We apply these techniques and a method of
Moser to approximate $\cC^k$-diffeomorphisms between totally real submanifolds
in $\C^n$ in the $\cC^k$-topology by biholomorphic mappings in tubes, by
unimodular and symplectic biholomorphic mappings, and by automorphisms of
$\C^n$.

</DOC>
<DOC>
<DOCNO> 40391 </DOCNO>
Mass generation and the dynamical role of the Katoptron Group


  Heavy mirror fermions along with a new strong gauge interaction capable of
breaking the electroweak gauge symmetry dynamically were recently introduced
under the name of katoptrons. Their main function is to provide a viable
alternative to the Standard-Model Higgs sector. In such a framework, ordinary
fermions acquire masses after the breaking of the strong katoptron group which
allows mixing with their katoptron partners. The purpose of this paper is to
study the elementary-scalars-free mechanism responsible for this breaking and
its implications for the fermion mass hierarchies.

</DOC>
<DOC>
<DOCNO> 9908 </DOCNO>
On the Effects of Changing the Boundary Conditions on the Ground State


  We compute and analyze couples of ground states of 3D spin glass systems with
the same quenched noise but periodic and anti-periodic boundary conditions for
different lattice sizes. We discuss the possible different behaviors of the
system, we analyze the average link overlap, the probability distribution of
window overlaps (among ground states computed with different boundary
conditions) and the spatial overlap and link overlap correlation functions. We
establish that the picture based on Replica Symmetry Breaking correctly
describes the behavior of 3D Spin Glasses.

</DOC>
<DOC>
<DOCNO> 10966 </DOCNO>
Numerical Studies of the two-leg Hubbard ladder


  The Hubbard model on a two-leg ladder structure has been studied by a
combination of series expansions at T=0 and the density-matrix renormalization
group. We report results for the ground state energy $E_0$ and spin-gap
$\Delta_s$ at half-filling, as well as dispersion curves for one and two-hole
excitations. For small $U$ both $E_0$ and $\Delta_s$ show a dramatic drop near
$t/t_{\perp}\sim 0.5$, which becomes more gradual for larger $U$. This
represents a crossover from a "band insulator" phase to a strongly correlated
spin liquid. The lowest-lying two-hole state rapidly becomes strongly bound as
$t/t_{\perp}$ increases, indicating the possibility that phase separation may
occur. The various features are collected in a "phase diagram" for the model.

</DOC>
<DOC>
<DOCNO> 85123 </DOCNO>
Mode Generating Mechanism in Inflation with Cutoff


  In most inflationary models, space-time inflated to the extent that modes of
cosmological size originated as modes of wavelengths at least several orders of
magnitude smaller than the Planck length. Recent studies confirmed that,
therefore, inflationary predictions for the cosmic microwave background
perturbations are generally sensitive to what is assumed about the Planck
scale. Here, we propose a framework for field theories on curved backgrounds
with a plausible type of ultraviolet cutoff. We find an explicit mechanism by
which during cosmic expansion new (comoving) modes are generated continuously.
Our results allow the numerical calculation of a prediction for the CMB
perturbation spectrum.

</DOC>
<DOC>
<DOCNO> 120587 </DOCNO>
Baryons in the Warm-Hot Intergalactic Medium


  Approximately 30-40% of all baryons in the present day universe reside in a
warm-hot intergalactic medium (WHIM), with temperatures between 10^5<T<10^7 K.
This is a generic prediction from six hydrodynamic simulations of currently
favored structure formation models having a wide variety of numerical methods,
input physics, volumes, and spatial resolutions. Most of these warm-hot baryons
reside in diffuse large-scale structures with a median overdensity around
10-30, not in virialized objects such as galaxy groups or galactic halos. The
evolution of the WHIM is primarily driven by shock heating from gravitational
perturbations breaking on mildly nonlinear, non-equilibrium structures such as
filaments. Supernova feedback energy and radiative cooling play lesser roles in
its evolution. WHIM gas is consistent with observations of the 0.25 keV X-ray
background without being significantly heated by non-gravitational processes
because the emitting gas is very diffuse. Our results confirm and extend
previous work by Cen & Ostriker and Dave' et al.

</DOC>
<DOC>
<DOCNO> 119358 </DOCNO>
Jets in quasars, microquasars and gamma-ray bursts


  Relativistic outflows are common in accreting and forming black holes.
Despite the enormous differences in scale, stellar-mass black holes in X-ray
binaries and supermassive black holes in Galactic Nuclei produce jets with
analogous properties. In both are observed two types of relativistic outflows:
1) quasi-steady compact jets with flat-spectrum, and 2) episodic large-scale
ejections with steep-spectrum and apparent superluminal motions. Because of the
short time scale of the phenomena in black hole binaries, the formation of
synchrotron jets is associated to changes in the X-ray thermal emission from
the accretion disk. Besides, the most common class of gamma-ray bursts can be
conceived as extreme microquasars, since they are afterglows from
ultra-relativistic jets associated to the formation of black holes at
cosmological distances.

</DOC>
<DOC>
<DOCNO> 12415 </DOCNO>
Coulomb interaction in oxygen \textit{p}-shell in LDA+U method and its


  Coulomb interaction between electrons on p-orbitals of oxygen atom in
strongly correlated compounds is not negligible, since its value (U_p) has
comparable order of magnitude with the value of Coulomb interaction on
d-orbitals of transition metal atom (U_d). We investigate the effect of taking
into account Coulomb correlations in oxygen p-shell in addition to the
correlations in the transition metal d-shell in frame of the LDA+U method. Our
calculations for NiO, MnO and La2CuO4 show that this additional correction in
general improves the agreement with experimental data for the spectral (energy
gap values, relative position of the main peaks in X-ray photoemission
spectroscopy (XPS) and Bremsstrahlung isohromate spectroscopy (BIS)) and
magnetic properties (magnetic moment values and intersite exchange interaction
parameters values).

</DOC>
<DOC>
<DOCNO> 40454 </DOCNO>
Top Physics


  The Run I experiments at the Fermilab Tevatron Collider discovered the top
quark and provided first measurements of many of its properties. Run II (and
eventually the LHC and NLC experiments) promise to extend our knowledge of the
top quark significantly. Understanding the top quark's large mass, and indeed
the origin of all mass, appears to require physics beyond the Standard Model.
Thus, the top quark may have unusual properties accessible to upcoming
experiments.

</DOC>
<DOC>
<DOCNO> 150689 </DOCNO>
Correlation functions of chiral primary operators in perturbative {\cal


  We discuss recent results on two-point functions of chiral primary operators
in {\cal N}=4 SU(N) supersymmetric Yang-Mills theory. Our results give further
support to the belief that such correlators are not renormalized to all orders
in g and to all orders in N.

</DOC>
<DOC>
<DOCNO> 152323 </DOCNO>
Matrix Model, Noncommutative Gauge Theory and the Tachyon Potential


  The D2brane-anti-D2brane system is described in the framework of BFSS Matrix
model and noncommutative (NC) gauge theory. The physical spectrum of fields is
found by appropriate gauge fixing. The exact tachyon potential is computed in
terms of these variables and an exact description of tachyon condensation
provided. We exhibit multiple vortex production with increasing topological
charge and interpret this as gradual conversion of the brane-antibrane system
to $D0$ branes. The entire analysis is carried out using the known hamiltonian
of the Matrix model, which is equivalent to the hamiltonian of the NC gauge
theory. We identify the supersymmetric ground state of this hamiltonian with
the tachyonic vacuum; Sen's conjecture about the latter follows simply from
this identification. We also find two types of closed string excitations,
solitonic (a la Dijkgraaf, Verlinde and Verlinde) as well as perturbative,
around the tachyonic vacuum.

</DOC>
<DOC>
<DOCNO> 69154 </DOCNO>
Preheating with extra dimensions


  We investigate preheating in a higher-dimensional generalized Kaluza-Klein
theory with a quadratic inflaton potential $V(\phi)=\frac12 m^2\phi^2$
including metric perturbations explicitly. The system we consider is the
multi-field model where there exists a dilaton field $\sigma$ which corresponds
to the scale of compactifications and another scalar field $\chi$ coupled to
inflaton with the interaction $\frac12 g^2\phi^2\chi^2+\tilde{g}^2\phi^3\chi$.
In the case of $\tilde{g}=0$, we find that the perturbation of dilaton does not
undergo parametric amplification while the $\chi$ field fluctuation can be
enhanced in the usual manner by parametric resonance. In the presence of the
$\tilde{g}^2\phi^3\chi$ coupling, the dilaton fluctuation in sub-Hubble scales
is modestly amplified by the growth of metric perturbations for the large
coupling $\tilde{g}$. In super-Hubble scales, the enhancement of the dilaton
fluctuation as well as metric perturbations is weak, taking into account the
backreaction effect of created $\chi$ particles. We argue that not only is it
possible to predict the ordinary inflationary spectrum in large scales but
extra dimensions can be held static during preheating in our scenario.

</DOC>
<DOC>
<DOCNO> 11608 </DOCNO>
Hedged Monte-Carlo: low variance derivative pricing with objective


  We propose a new `hedged' Monte-Carlo (HMC) method to price financial
derivatives, which allows to determine simultaneously the optimal hedge. The
inclusion of the optimal hedging strategy allows one to reduce the financial
risk associated with option trading, and for the very same reason reduces
considerably the variance of our HMC scheme as compared to previous methods.
The explicit accounting of the hedging cost naturally converts the objective
probability into the `risk-neutral' one. This allows a consistent use of purely
historical time series to price derivatives and obtain their residual risk. The
method can be used to price a large class of exotic options, including those
with path dependent and early exercise features.

</DOC>
<DOC>
<DOCNO> 101213 </DOCNO>
Variance of the spectral numbers


  A formula for the variance of the spectrum of a quasihomogeneous singularity
is proved, using the G-function of a semisimple Frobenius manifold.

</DOC>
<DOC>
<DOCNO> 8901 </DOCNO>
Evolution of the universality class in slightly diluted (1>p>0.8) Ising


  The crossover of a pure (undiluted) Ising system (spin per site probability
p=1) to a diluted Ising system (spin per site probability p<0.8) is studied by
means of Monte Carlo calculations with p ranging between 1 and 0.8 at intervals
of 0.025. The evolution of the self averaging is analyzed by direct
determination of the normalized square widths for magnetization and
susceptibility as a function of p. We find a monotonous and smooth evolution
from the pure to the randomly diluted universality class. The p-dependent
transition is found to be independent of the size (L). This property is very
convenient for extrapolation towards the randomly diluted universality class
avoiding complications resulting from finite size effects.

</DOC>
<DOC>
<DOCNO> 70256 </DOCNO>
NLO evolution kernels for skewed transversity distributions


  We present a calculation of the two-loop evolution kernels of the twist-two
transversally polarized quark and linearly polarized gluon skewed parton
distributions in the minimal subtraction scheme and discuss a solution of the
evolution equations suitable for numerical implementations.

</DOC>
<DOC>
<DOCNO> 117477 </DOCNO>
Discovery of 9 Ly alpha emitters at redshift z~3.1 using narrow-band


  Narrow-band imaging surveys aimed at detecting the faint emission from the
5007 [O III] line of intracluster planetary nebulae in Virgo also probe high
redshift z=3.1 Ly alpha emitters. Here we report on the spectroscopic
identification of 9 Ly alpha emitters at z=3.13, obtained with the FORS
spectrograph at Unit 1 of the ESO Very Large Telescope (VLT UT1). The spectra
of these high redshift objects show a narrow, isolated Ly alpha emission with
very faint (frequently undetected) continuum, indicating a large equivalent
width. No other features are visible in our spectra. Our Ly alpha emitters are
quite similar to those found by Hu (1998), Cowie & Hu (1998) and Hu et al.
(1998). Using simple population synthesis models, on the assumption that these
sources are regions of star formation, we conclude that the nebulae are nearly
optically thick and must have a very low dust content, in order to explain the
high observed Ly alpha equivalent widths. For the cosmological and star
formation parameters we adopted, the total stellar mass produced would seem to
correspond to the formation of rather small galaxies, some of which are perhaps
destined to merge. The implied star formation density in our sampled comoving
volume is probably somewhat smaller than, but of the same order of magnitude as
the star formation density at z=3 derived by other authors from Lyman-break
galaxy surveys. This result agrees with the expectation that the Ly alpha
emitters are a low-metallicity (or low-dust) tail in a distribution of star
forming regions at high redshifts. Finally, the Ly alpha emitters may
contribute as many H-ionizing photons as QSOs at z=3.

</DOC>
<DOC>
<DOCNO> 122456 </DOCNO>
Properties and nature of Be stars. XX. Binary nature and orbital


  An analysis of accurate radial velocities (RVs) of the Be star gamma Cas from
295 Reticon spectrograms secured between October 1993 and May 2000 allowed us
to prewhiten the RVs for the long-term changes and to obtain the first orbital
RV curve of this star. The orbital period is 203d59 and the orbit has an
eccentricity of 0.26. The orbital motion is detectable even in the published
velocities, based on photographic spectra. This implies that gamma Cas is a
primary component of a spectroscopic binary. The secondary has a mass of about
1 solar mass, appropriate for a white dwarf or a neutron star, but it could
also be a normal late-type dwarf. The ultimate solution of the dispute whether
the observed X-ray emission is associated with the secondary or with the
primary will need further dedicated studies.

</DOC>
<DOC>
<DOCNO> 102675 </DOCNO>
Large Deviation Principles and Complete Equivalence and Nonequivalence


  We consider a general class of statistical mechanical models of coherent
structures in turbulence, which includes models of two-dimensional fluid
motion, quasi-geostrophic flows, and dispersive waves. First, large deviation
principles are proved for the canonical ensemble and the microcanonical
ensemble. For each ensemble the set of equilibrium macrostates is defined as
the set on which the corresponding rate function attains its minimum of 0. We
then present complete equivalence and nonequivalence results at the level of
equilibrium macrostates for the two ensembles.

</DOC>
<DOC>
<DOCNO> 70091 </DOCNO>
Magnetogenesis and the dynamics of internal dimensions


  The dynamical evolution of internal space-like dimensions breaks the
invariance of the Maxwell's equations under Weyl rescaling of the (conformally
flat) four-dimensional metric. Depending upon the number and upon the dynamics
of internal dimensions large scale magnetic fields can be created. The
requirements coming from magnetogenesis together with the other cosmological
constraints are examined under the assumption that the internal dimensions
either grow or shrink (in conformal time) prior to a radiation dominated epoch.
If the internal dimensions are growing the magnitude of the generated magnetic
fields can seed the galactic dynamo mechanism.

</DOC>
<DOC>
<DOCNO> 68718 </DOCNO>
The topological susceptibility and f_pi from lattice QCD


  We study the topological susceptibility, chi, in QCD with two quark flavours
using the lattice field configurations recently produced by the UKQCD
collaboration. We find clear evidence for the expected suppression at small
quark mass, and examine the variation of chi with this mass. The resulting
estimate of the pion decay constant, f_pi = 105 +/- 5 +18/-10 MeV, is
consistent with the experimental value of approximately 93 MeV. We compare chi
to the large-N_c prediction and find consistency over a large range of quark
masses. The benefits of the non-perturbative action improvement scheme and the
matched lattice spacings between simulation ensembles are discussed. We compare
our results with other studies and suggest a reason why such a quark mass
dependence has not been previously seen.

</DOC>
<DOC>
<DOCNO> 9140 </DOCNO>
Role of Phase Variables in Quarter-Filled Spin Density Wave States


  Several kinds of spin density wave (SDW) states with both quarter-filled band
and dimerization are reexamined for a one-dimensional system with on-site,
nearest-neighbor and next-nearest-neighbor repulsive interactions, which has
been investigated by Kobayashi et al. (J. Phys. Soc. Jpn. 67 (1998) 1098).
Within the mean-field theory, the ground state and the response to the density
variation are calculated in terms of phase variables, $\theta$ and $\phi$,
where $\theta$ expresses the charge fluctuation of SDW and $\phi$ describes the
relative motion between density wave with up spin and that with down spin
respectively. It is shown that the exotic state of coexistence of 2k_F-SDW and
2k_F-charge density wave (CDW) is followed by 4k_F-SDW but not by 4k_F-CDW
where k_F denotes a Fermi wave vector. The harmonic potential with respect to
the variation of $\theta$ and/or $\phi$ disappears for the interactions, which
lead to the boundary between the pure 2k_F-SDW state and the corresponding
coexistent state.

</DOC>
<DOC>
<DOCNO> 9722 </DOCNO>
Separable Structure of Many-Body Ground-State Wave Function


  We have investigated a general structure of the ground-state wave function
for the Schr\"odinger equation for $N$ identical interacting particles (bosons
or fermions) confined in a harmonic anisotropic trap in the limit of large $N$.
It is shown that the ground-state wave function can be written in a separable
form. As an example of its applications, this form is used to obtain the
ground-state wave function describing collective dynamics for $N$ trapped
bosons interacting via contact forces.

</DOC>
<DOC>
<DOCNO> 39825 </DOCNO>
Measurement of Structure Dependent K^+ -> mu^+ nu gamma


  We report the first measurement of a structure dependent component in the
decay K^+ -> mu^+ nu gamma. Using the kinematic region where the muon kinetic
energy is greater than 137 MeV and the photon energy is greater than 90 MeV, we
find that the absolute value of the sum of the vector and axial-vector form
factors is |F_V+F_A| =0.165 \pm 0.007 \pm 0.011. This corresponds to a
branching ratio of BR(SD^+) = (1.33 \pm 0.12 \pm 0.18) \times 10^{-5}. We also
set the limit -0.04 < F_V-F_A < 0.24 at 90% c.l.

</DOC>
<DOC>
<DOCNO> 122932 </DOCNO>
How to measure CMB polarization power spectra without losing information


  We present a method for measuring CMB polarization power spectra given
incomplete sky coverage and test it with simulated examples such as Boomerang
2001 and MAP. By augmenting the quadratic estimator method with an additional
step, we find that the E and B power spectra can be effectively disentangled on
angular scales substantially smaller than the width of the sky patch in the
narrowest direction. We find that the basic quadratic and maximum-likelihood
methods display a unneccesary sensitivity to systematic errors when T-E
cross-correlation is involved, and show how this problem can be eliminated at
negligible cost in increased error bars. We also test numerically the widely
used approximation that sample variance scales inversely with sky coverage, and
find it to be an excellent approximation on scales substantially smaller than
the sky patch.

</DOC>
<DOC>
<DOCNO> 118643 </DOCNO>
The Interstellar Medium of Young Stellar Clusters from the Mid-Infrared


  Effects of young stellar clusters on their gas and dust environment are
probed using mid-infrared (MIR) wavelengths. The strong MIR [NeIII]/[NeII]
ratios (5 to 10) reveal the presence of current massive stars less than 5 Myr.
Using MIR line ratios along with optical and NIR data from the literature,
composite SEDs are constructed for NGC 1569, NGC 1140 and IIZw40. The stellar
SEDs are then used as input to a dust model to study the impact of the hard,
penetrating radiation field on the dust components, particularly in low
metallicity environments, where the destructive effects of the massive stellar
clusters on the environments occur on global scales. For example, the smallest
dust particles are destroyed over larger regions in the dwarf galaxies than in
normal metallicity starbursts.

</DOC>
<DOC>
<DOCNO> 67749 </DOCNO>
BFKL Monte Carlo for Dijet Production at Hadron Colliders


  The production of jet pairs at large rapidity difference at hadron colliders
is potentially sensitive to BFKL physics. We present the results of a BFKL
Monte Carlo calculation of dijets at the Tevatron. The Monte Carlo incorporates
kinematic effects that are absent in analytic BFKL calculations; these effects
significantly modify the behavior of dijet cross sections.

</DOC>
<DOC>
<DOCNO> 8225 </DOCNO>
Interaction-assisted propagation of Coulomb-correlated electron-hole


  A two-band model of a disordered semiconductor is used to analyze dynamical
interaction induced weakening of localization in a system that is accessible to
experimental verification. The results show a dependence on the sign of the
two-particle interaction and on the optical excitation energy of the
Coulomb-correlated electron-hole pair.

</DOC>
<DOC>
<DOCNO> 83316 </DOCNO>
Parameter-free Model of Rank Polysemantic Distribution


  A model of rank polysemantic distribution with a minimal number of fitting
parameters is offered. In an ideal case a parameter-free description of the
dependence on the basis of one or several immediate features of the
distribution is possible.

</DOC>
<DOC>
<DOCNO> 12138 </DOCNO>
Phonon emission and absorption in the fractional quantum Hall effect


  We investigate the time dependent thermal relaxation of a two-dimensional
electron system in the fractional quantum Hall regime where ballistic phonons
are used to heat up the system to a non-equilibrium temperature. The thermal
relaxation of a 2DES at $\nu=1/2$ can be described in terms of a broad band
emission of phonons, with a temperature dependence proportional to $T^4$. In
contrast, the relaxation at fractional filling $\nu=2/3$ is characterized by
phonon emission around a single energy, the magneto-roton gap. This leads to a
strongly reduced energy relaxation rate compared to $\nu=1/2$ with only a weak
temperature dependence for temperatures 150 mK $< T <$ 400 mK.

</DOC>
<DOC>
<DOCNO> 119313 </DOCNO>
The flatness of the Universe is robust


  We combine the two balloon experiments BOOMERANG and MAXIMA-1 with our
previous fit which used 9 constraints and concluded that the Universe is flat.
The result is that the flatness is robust, $\Omega_0 = 0.97 \pm 0.05$.

</DOC>
<DOC>
<DOCNO> 150987 </DOCNO>
2T Physics Formulation of Superconformal Dynamics Relating to Twistors


  The conformal symmetry SO(d,2) of the massless particle in d dimensions, or
superconformal symmetry OSp(N|4), SU(2,2|N), OSp(8|N) of the superparticle in
d=3,4,6 dimensions respectively, had been previously understood as the global
Lorentz symmetry and supersymmetries of 2T physics in d+2 dimensions. By
utilising the gauge symmetries of 2T physics, it is shown that the dynamics can
be cast in terms of superspace coordinates, momenta and theta variables or in
terms of supertwistor variables a la Penrose and Ferber. In 2T physics these
can be gauge transformed to each other. In the supertwistor version the
quantization of the model amounts to the well known oscillator formalism for
non-compact supergroups.

</DOC>
<DOC>
<DOCNO> 68266 </DOCNO>
Weak Phase $\gamma$ and Strong Phase $\delta$ from CP Averaged $B\to


  Assuming SU(3) symmetry for the strong phases in the four decay modes
$B\rarrow \pi^-\pi^+, \pi^0 \pi^+, \pi^- K^+, \pi^- \bar{K}^0$ and ignoring the
relative small electroweak penguin effects in those decays, the weak phase
$\gamma$ and the strong phase $\delta$ can be determined in a model independent
way by the CP-averaged branching ratios of the four decay modes. It appears
that the current experimental data for $B\to \pi\pi$ and $\pi K$ decays prefer
a negative value of $\cos\gamma\cos\delta$. By combining with the other
constraints from $V_{ub}$, $B^{0}_{d,s}-\bar{B}^{0}_{d,s}$ mixings and indirect
CP-violating parameter $\epsilon_K$ within the standard model, two favorable
solutions for the phases $\gamma$ and $\delta$ are found to lie in the region:
$35^{\circ}\alt\gamma\alt 62^{\circ}$ and $106^{\circ}\alt \delta \alt
180^{\circ}$ or $86^{\circ}\alt\gamma\alt 151^{\circ}$ and
$0^{\circ}\alt\delta\alt 75^{\circ} $ within 1$\sigma$ standard deviation. It
is noted that if allowing the standard deviation of the data to be more than
1$\sigma$, the two solutions could approach to one solution with a much larger
region for the phases $\gamma$ and $\delta$. Direct CP asymme try
$a_{\epsilon''}^{(\pi^- K^+)}$ in $B\rarrow \pi^-K^+$ decay can be as large as
the present experimental upper bound. Direct CP asymmetry
$a_{\epsilon''}^{(\pi^+\pi^-)}$ in $B\rarrow \pi^-\pi^+$ decay can reach up to
about 40% at 1$\sigma$ level.

</DOC>
<DOC>
<DOCNO> 70483 </DOCNO>
Color transparency in deeply inelastic diffraction


  We suggest a simple physical picture for the diffractive parton distributions
that appear in diffractive deeply inelastic scattering. In this picture,
partons impinging on the proton can have any transverse separation, but only
when the separation is small can they penetrate the proton without breaking it
up. By comparing the predictions from this picture with the diffractive data
from HERA, we determine rough values for the small separations that dominate
the diffraction process.

</DOC>
<DOC>
<DOCNO> 70888 </DOCNO>
Neutrino-electron processes in a dense maqnetized plasma


  The neutrino-electron processes in a dense strongly degenerate magnetized
plasma are analyzed in the framework of the Standard Model. The total
probability and the mean values of the neutrino energy and momentum losses are
calculated. It is shown that neutrino scattering on the excited electrons with
Landau level number conservation dominates under the conditions "mu^2 > eB >>
mu T" but does not give a contribution into the neutrino force acting on plasma
along the magnetic field.

</DOC>
<DOC>
<DOCNO> 101697 </DOCNO>
On nice equivalence relations on 2^\lambda


  The main question here is the possible generalization of the following
theorem on ``simple'' equivalence relation on 2^omega to higher cardinals.
  Theorem: (1) Assume that:
  (a) E is a Borel 2-place relation on 2^omega,
  (b) E is an equivalence relation,
  (c) if eta, nu in 2^omega and (exists ! n)(eta(n) not= nu(n)), then eta, nu
are not E --equivalent.
  Then there is a perfect subset of 2^omega of pairwise non E-equivalent
members.
  (2) Instead of ``E is Borel'', ``E is analytic (or even a Borel combination
of analytic relations)'' is enough.
  (3) If E is a Pi^1_2 relation which is an equivalence relation satisfying
clauses (b)+(c) in V^Cohen, then the conclusion of (1) holds.

</DOC>
<DOC>
<DOCNO> 71079 </DOCNO>
Introduction to Effective Field Theory


  An introduction to methods of effective field theory is given. Examples are
presented, including Rayleigh scattering from nonrelativistic quantum mechnics,
chiral perturbation theory/QCD as well as electromagnetic and weak interactions
of nucleons.

</DOC>
<DOC>
<DOCNO> 120719 </DOCNO>
Caltech Faint Galaxy Redshift Survey XIV: Galaxy Morphology in the HDF


  Morphological classifications are reported for Hubble Space Telescope (HST)
images of 241 galaxies in the Hubble Deep Field (HDF) and its Flanking Fields
(FF) with measured redshifts in the interval 0.25 < z < 1.2, drawn from a
magnitude-limited redshift survey to R = 24.0. The galaxies are divided into
three groups with redshifts in the intervals [0.25,0.6], [0.6,0.8], [0.8,1.2].
R606 images from the first group and I814 images from the second and third
groups are compared with B-band images of nearby galaxies. All classifications
were therefore made at approximately the same rest wavelength. Selection biases
are discussed. We corroborate and extend the results of earlier investigations
by observing that: Most intermediate and late-type galaxies with $z\gtrsim0.5$
have morphologies that are dramatically different from those of local galaxies
and cannot be shoehorned into the Hubble ``tuning fork'' classification scheme.
Grand-design spirals appear to be rare or absent for $z\gtrsim0.3$. Many Sa and
Sb spirals with $z\gtrsim0.6$ do not exhibit well-defined spiral arms. The arms
of distant Sc galaxies appear more chaotic than those of their nearby
counterparts. (abridged) On the basis of these and similar observations, it is
inferred that the development of pronounced spiral structure was delayed until
\~5 Gyr and that most bulges are probably not formed by disintegrating bars.
Major morphological changes were still taking place only ~5 Gyr ago even though
changes in the integrated light of most galaxies were then much slower than
they were ~10 Gyr ago.

</DOC>
<DOC>
<DOCNO> 12607 </DOCNO>
Entropic nonextensivity: A possible measure of complexity


  An updated review [1] of nonextensive statistical mechanics and
thermodynamics is colloquially presented. Quite naturally the possibility
emerges for using the value of q-1 (entropic nonextensivity) as a simple and
efficient manner to provide, at least for some classes of systems, some
characterization of the degree of what is currently referred to as complexity
[2]. A few historical digressions are included as well.

</DOC>
<DOC>
<DOCNO> 72235 </DOCNO>
Top flavour-changing neutral coupling signals at a linear collider


  We present an analysis of the sensitivity of the TESLA e+ e- collider to top
flavour-changing neutral couplings to the Z boson and photon. We consider the
cases without beam polarization, with only e- polarization and with e- and e+
polarization, showing that the use of the latter substantially enhances the
sensitivity to discover or bound these vertices. For some of the couplings the
expected LHC limits could be improved up to an order of magnitude for equal
running times.

</DOC>
<DOC>
<DOCNO> 116314 </DOCNO>
Teaching the EPR-Paradox at High School?


  The discovery of quantum mechanics at the beginning of the last century led
to a revolution of the physical world view. Modern experiments, made possible
by new techniques on the border of the classical and the quantum regimes offer
new insights and better understanding of the quantum world and have impact on
technical development. Therefore it seems important that students gain
appreciation of the principles of quantum mechanics. A suitable way seems be
the treatment of the EPR-experiment at a prominent place.

</DOC>
<DOC>
<DOCNO> 116617 </DOCNO>
Does Special Relativity Have Limits of Applicability in the Domain of


  We have shown in the paper that for time with fractional dimensions
(multifractal time theory) there are small domain of velocities $v$ near $v=c$
where SR must be replaced by fractal theory of almost inertial system that do
not contains an infinity and permits moving with arbitrary velocities.

</DOC>
<DOC>
<DOCNO> 170758 </DOCNO>
Semiclassical Casimir Energies at Finite Temperature


  We study the dependence on the temperature T of Casimir effects for a range
of systems, and in particular for a pair of ideal parallel conducting plates,
separated by a vacuum. We study the Helmholtz free energy, combining
Matsubara's formalism, in which the temperature appears as a periodic Euclidean
fourth dimension of circumference 1/T, with the semiclassical periodic orbital
approximation of Gutzwiller. By inspecting the known results for the Casimir
energy at T=0 for a rectangular parallelepiped, one is led to guess at the
expression for the free energy of two ideal parallel conductors without
performing any calculation. The result is a new form for the free energy in
terms of the lengths of periodic classical paths on a two-dimensional cylinder
section. This expression for the free energy is equivalent to others that have
been obtained in the literature. Slightly extending the domain of applicability
of Gutzwiller's semiclassical periodic orbit approach, we evaluate the free
energy at T>0 in terms of periodic classical paths in a four-dimensional cavity
that is the tensor product of the original cavity and a circle. The validity of
this approach is at present restricted to particular systems. We also discuss
the origin of the classical form of the free energy at high temperatures.

</DOC>
<DOC>
<DOCNO> 68701 </DOCNO>
A Solution of the Randall-Sundrum Model and the Mass Hierarchy Problem


  A solution of the Randall-Sundrum model for a simplified case (one wall) is
obtained. It is given by the $1/k^2$-expansion (thin wall expansion) where
$1/k$ is the {\it thickness} of the domain wall. The vacuum setting is done by
the 5D Higgs potential and the solution is for a {\it family} of the Higgs
parameters. The mass hierarchy problem is examined. Some physical quantities in
4D world such as the Planck mass, the cosmological constant, and fermion masses
are focussed. Similarity to the domain wall regularization used in the chiral
fermion problem is explained. We examine the possibility that the 4D massless
chiral fermion bound to the domain wall in the 5D world can be regarded as the
real 4D fermions such as neutrinos, quarks and other leptons.

</DOC>
<DOC>
<DOCNO> 119699 </DOCNO>
Thermonuclear Explosions of Chandrasekhar-Mass White Dwarfs


  We present a new way of modeling turbulent thermonuclear deflagration fronts
in Chandrasekhar-mass white dwarfs, consisting of carbon and oxygen, undergoing
a type Ia supernova explosion. Our approach is a front capturing/tracking
hybrid scheme, based on a level set method, which treats the front as a
mathematical discontinuity and allows for full coupling between the front
geometry and the flow field. First results of the method applied to the problem
of type Ia supernovae are discussed. It will be shown that even in 2-D and even
with a physically motivated sub-grid model numerically ``converged'' results
are difficult to obtain.

</DOC>
<DOC>
<DOCNO> 121076 </DOCNO>
Evidence for a Massive Dark Object in NGC 4350


  In this work we build a detailed dynamic model for a S0 galaxy possibly
hosting a central massive dark object (MDO). We show that the photometric
profiles and the kinematics along the major and minor axes, including the h3
and h4 profiles, imply the presence of a central MDO of mass M = 1.5 - 9.7 10^8
solar masses, i.e. 0.3-2.8% of the mass derived for the stellar spheroidal
component. Models without MDO are unable to reproduce the kinematic properties
of the inner stars and of the rapidly rotating nuclear gas.
  The stellar population comprise of an exponential disc (27% of the light) and
a diffuse spheroidal component (73% of the light) that cannot be represented by
a simple de Vaucouleurs profile at any radius. The M/L ratios we found for the
stellar components (respectively 3.3 and 6.6) are typical of those of disc and
elliptical galaxies.

</DOC>
<DOC>
<DOCNO> 9381 </DOCNO>
Role of in-plane dissipation in dynamics of Josephson lattice in


  We calculate the flux-flow resistivity of the Josephson vortex lattice in a
layered superconductor taking into account both the inter-plane and in-plane
dissipation channels. We consider the limiting cases of small fields (isolated
vortices) and high fields (overlapping vortices). In the case of the dominating
in-plane dissipation, typical for high-temperature superconductors, the field
dependence of flux-flow resistivity is characterized by {\it three} distinct
regions. As usual, at low fields the flux-flow resistivity grows linearly with
field. When the Josephson vortices start to overlap the flux-flow resistivity
crosses over to the regime of {\it quadratic} field dependence. Finally, at
very high fields the flux-flow resistivity saturates at the c-axis
quasiparticle resistivity. The intermediate quadratic regime indicates dominant
role of the in-plane dissipation mechanism. Shape of the field dependence of
the flux-flow resistivity can be used to extract both components of the
quasiparticle

</DOC>
<DOC>
<DOCNO> 121912 </DOCNO>
Polarization and Extent of Maser Emission from Late-Type Stars: Support


  The integrated spectrum of OH emission from late-type stars is often
circularly polarized, by as much as 50% in some cases. While the spectra are
partially polarized, the individual maser components revealed by VLBI are much
more so. Using VLBI observations of late-type stars from the literature, we
show that the difference in circular polarization between main lines correlates
with a difference in angular extent for a given object. This is a natural
result if turbulent magnetic fields are causing the masers to be polarized via
the Cook mechanism, and might serve as a good diagnostic for determining which
objects should be investigated in the search for magnetic fields around evolved
stars.

</DOC>
<DOC>
<DOCNO> 11329 </DOCNO>
Spin diffusion in doped semiconductors: the role of Coulomb interactions


  We examine the effect of the Coulomb interaction on the mobility and
diffusion of spin packets in doped semiconductors. We find that the diffusion
constant is reduced, relative to its non-interacting value, by the combined
effect of Coulomb-enhanced spin susceptibility and spin Coulomb drag. In
ferromagnetic semiconductors, the spin diffusion constant vanishes at the
ferromagnetic transition temperature.

</DOC>
<DOC>
<DOCNO> 8356 </DOCNO>
Step wise destruction of the pair correlations in micro clusters by a


  The response of $nm$-size spherical superconducting clusters to a magnetic
field is studied for the canonical ensemble of electrons in a single degenerate
shell. For temperatures close to zero, the discreteness of the electronic
states causes a step like destruction of the pair correlations with increasing
field strength, which shows up as peaks in the susceptibility and heat
capacity.
 At higher temperatures the transition becomes smoothed out and extends to
field strengths where the pair correlations are destroyed at zero temperature.

</DOC>
<DOC>
<DOCNO> 117567 </DOCNO>
The influence of nova nucleosynthesis on the chemical evolution of the


  We adopt up-to-date yields of 7Li, 13C, 15N from classical novae and use a
well tested model for the chemical evolution of the Milky Way in order to
predict the temporal evolution of these elemental species in the solar
neighborhood. In spite of major uncertainties due to our lack of knowledge of
metallicity effects on the final products of explosive nucleosynthesis in nova
outbursts, we find a satisfactory agreement between theoretical predictions and
observations for 7Li and 13C. On the contrary, 15N turns out to be overproduced
by about an order of magnitude.

</DOC>
<DOC>
<DOCNO> 11740 </DOCNO>
Unique Translation between Hamiltonian Operators and Functional


  A careful treatment of the discretization errors in the path integral
formulation of quantum mechanics leads to a unique prescription for the
translation from the Hamiltonian to the action in the functional integral. An
example is given by an interaction quadratic in the occupation number,
characteristic for manybody bosonic systems. As a result, the term linear in
the occupation number (chemical potential) receives a correction as compared to
the usual formulation based on coherent states. A perturbative calculation
supports the relevance of this correction.

</DOC>
<DOC>
<DOCNO> 10266 </DOCNO>
Maximum entropy production as a selection principle for non-equilibrium


  We consider the macroscopic evolution of a non-equilibrium, open system over
a time interval of length tau. An information theoretic derivation is given of
the probability distribution of the underlying phase space trajectories. The
result leads immediately to the Fluctuation Theorem in the case of
microscopically reversible dynamics. In the limit as tau tends to infinity the
result implies that non-equilibrium steady states are states of maximum entropy
production, empirical evidence for which has been found in independent studies
of the earth's climate and crystal growth morphology.

</DOC>
<DOC>
<DOCNO> 170059 </DOCNO>
Optical realization of universal quantum cloning


  Beyond the no-cloning theorem, the universal symmetric quantum cloning
machine was first addressed by Buzek and Hillery. Here, we realized the
one-to-two qubits Buzek-Hillery cloning machine with linear optical devices.
This method relies on the representation of several qubits by a single photon.
We showed that, the fidelities between the two output qubits and the original
qubit are both 5/6 (which proved to be the optimal fidelity of one-to-two
qubits universal cloner) for arbitrary input pure states.

</DOC>
<DOC>
<DOCNO> 179034 </DOCNO>
On Charm Production near the Phase Boundary


  We discuss aspects of the statistical hadronization model for the production
of mesons with open and hidden charm in ultra-relativistic nuclear collisions.
Emphasis is placed on what can be inferred from the dependence of the yield of
charmonia on the number of participants in the collisions.

</DOC>
<DOC>
<DOCNO> 101084 </DOCNO>
QDYBE: some explicit formulas for exchange matrix and related objects in


  This mainly tutorial paper is intended as a somewhat larger example for parts
of the theory exposed in the Lectures on the dynamical Yang-Baxter equations by
P. Etingof and O. Schiffmann, math.QA/9908064. We explicitly compute the matrix
entries of the intertwining operator, fusion matrix and exchange matrix
associated to sl(2,R) for q=1. We also consider the weighted trace function and
the dual Macdonald-Ruijsenaars equation for this particular case. As expected,
the matrix entries of the exchange matrix turn out to be Racah polynomials.
However, the road to their explicit formula via the fusion matrix is quick, and
it also yields an interesting way to derive their orthogonality relations.

</DOC>
<DOC>
<DOCNO> 100925 </DOCNO>
On finitization of the Gordon identities


  In this paper we prove the identity that generalizes the Andrews-Gordon
identity. Also we discuss the relation of our formula to the geometry of affine
flag varieties and to the geometry of polyhedra.

</DOC>
<DOC>
<DOCNO> 12211 </DOCNO>
Speeding protein folding beyond the Go model: How a little frustration


  Perturbing a Go model towards a realistic protein Hamiltonian by adding
non-native interactions, we find that the folding rate is in general enhanced
as ruggedness is initially increased, as long as the protein is sufficiently
large and flexible. Eventually the rate drops rapidly towards zero when
ruggedness significantly slows conformational transitions. Energy landscape
arguments for thermodynamics and kinetics are coupled with a treatment of
non-native collapse to elucidate this effect.

</DOC>
<DOC>
<DOCNO> 178503 </DOCNO>
Theory of doorway states for one-nucleon transfer reactions. II.


  The correlation effects in nuclei owing to which the nuclear wave functions
are different from the Slater determinants are studied on the basis of the
original theory. The calculated numbers of nucleons out of the nuclear
Fermi-surface are in reasonable agreement with the finding from the
high-momentum components of the nucleon momentum distributions in nuclei. The
problems concerning the nuclear binding energy are also discussed.

</DOC>
<DOC>
<DOCNO> 71951 </DOCNO>
Chiral loop and LsigmaM predictions for phi->pi0etagamma


  A prediction for the contributions of chiral loops and the L$\sigma$M model
to the radiative $\phi\to\pi^0\eta\gamma$ decay mode is presented. The
L$\sigma$M is used as an appropriate framework for describing the pole effects
of the $a_0(980)$ scalar resonance. As a result, a better agreement with
present available data is achieved for the higher part of the $\pi^0\eta$
invariant mass spectrum. For the branching ratio, a value of
$B(\phi\to\pi^0\eta\gamma)=(0.75$--$0.95)\times 10^{-4}$ is found.

</DOC>
<DOC>
<DOCNO> 68359 </DOCNO>
Resonance Production of Three Neutral Supersymmetric Higgs Bosons at LHC


  Multiple production of Higgs particles is essential to study Higgs
self-couplings at future high-energy colliders. In this paper we calculated the
resonance contributions to the production of three lightest neutral
supersymmetric Higgs bosons in gluon fusion at LHC. The cross sections due to
trilinear Higgs couplings is sizeable but the measurement of the quartic
coupling hhhH(h) seems to be impossible.

</DOC>
<DOC>
<DOCNO> 118047 </DOCNO>
Post-Glitch RXTE-PCA Observations of the Vela Pulsar


  We report the results of analysis of observations of the Vela Pulsar by PCA
on RXTE. Our data consists of two parts. The first part contains observations
at 1, 4, and 9 days after the glitch in 1996 and has 27000 sec. total exposure
time. The second part of observations were performed three months after this
glitch and have a total exposure time of 93000 sec. We found pulsations in both
sets. The observed spectrum is a power-law with no apparent change in flux or
count rate. The theoretical expectations of increase in flux due to internal
heating after a glitch are smaller than the uncertainty of the observations.

</DOC>
<DOC>
<DOCNO> 150324 </DOCNO>
Type I' and Real Algebraic Geometry


  We revisit the duality between type I' and heterotic strings in 9 dimensions.
We resolve a puzzle about the validity of type I' perturbation theory and show
that there are regions in moduli which are not within the reach of type I'
perturbation theory. We find however, that all regions of moduli are described
by a special class of real elliptic $K3$'s in the limit where the $K3$ shrinks
to a one dimensional interval. We find a precise map between the geometry of
dilaton and branes of type I' on the one hand and the geometry of real elliptic
$K3$ on the other. We also argue more generally that strong coupling limits of
string compactifications generically do not have a weakly coupled dual in terms
of any known theory (as is exemplified by the strong coupling limit of
heterotic strings in 9 dimensions for certain range of parameters).

</DOC>
<DOC>
<DOCNO> 8929 </DOCNO>
Stripe glasses: self generated randomness in a uniformly frustrated


  We show that a system with competing interactions on different length scales,
as relevant for the formation of stripes in doped Mott insulators, undergoes a
self-generated glass transition which is caused by the frustrated nature of the
interactions and not related to the presence of quenched disorder. An
exponentially large number of metastable configurations is found, leading to a
slow, landscape dominated long time relaxation and a break up of the system
into a disordered inhomogeneous state.

</DOC>
<DOC>
<DOCNO> 12327 </DOCNO>
Stability of inverse bicontinuous cubic phases in lipid-water mixtures


  We investigate the stability of seven inverse bicontinuous cubic phases ($G$,
$D$, $P$, $C(P)$, $S$, $I-WP$, $F-RD$) in lipid-water mixtures based on a
curvature model of membranes. Lipid monolayers are described by parallel
surfaces to triply periodic minimal surfaces. The phase behavior is determined
by the distribution of the Gaussian curvature on the minimal surface and the
porosity of each structure. Only $G$, $D$ and $P$ are found to be stable, and
to coexist along a triple line. The calculated phase diagram agrees very well
with experimental results for 2:1 lauric acid/DLPC.

</DOC>
<DOC>
<DOCNO> 12375 </DOCNO>
Where is the pi particle?


  We discuss the interplay of particle-particle and particle-hole spin-triplet
channels in high-T_c superconductors using a quasiparticle dispersion motivated
by angle-resolved photoemission. Within a generalized RPA, we find a well
defined antibound state of two holes, the pi resonance of Demler and Zhang, as
well as a bound state of a particle and a hole, the spin exciton. We show that
the energy of the pi resonance always exceeds 2 Delta, twice the maximum d-wave
gap, therefore the neutron resonance observed in the cuprates around energy
Delta is most likely a spin exciton. At the same time, we speculate that the pi
particle can exist at higher energies and might be observed in neutron
scattering around 100 meV.

</DOC>
<DOC>
<DOCNO> 122376 </DOCNO>
Cosmochemistry in the early Universe


  At early times the Universe was filled up with an extremely dense and hot
gas. Due to the expansion it cooled below the binding energies of atoms which
led to the formation of the first nuclei. In the physical environment of the
post-recombination period of hydrogen, molecules such as $H_2$, $HD$ and $LiH$
can be formed. The proto-object formation, resulting from the growth of linear
density fluctuations in the early Universe, can have an important impact on the
chemical state of the Universe. Hence it can be enriched with metals, and thus
lead to the formation of the first pre-biotic molecules. In this contribution,
I will present some scheme for the formation of primordial molecules and
discuss the consequence of the formation of first stars on the existence of
possible primordial pre-biotic.

</DOC>
<DOC>
<DOCNO> 72157 </DOCNO>
Relationship of pionium lifetime with pion scattering lengths in


  The pionium lifetime is calculated in the framework of the
quasipotential-constraint theory approach, including the sizable
electromagnetic corrections. The framework of generalized chiral perturbation
theory allows then an analysis of the lifetime value as a function of the pion
S-wave scattering lengths with isospins I=0,2, the latter being dependent on
the quark condensate value.

</DOC>
<DOC>
<DOCNO> 71673 </DOCNO>
Finite Gluons Ladders and Hadronic Collisions


  A truncated BFKL series is studied and applied to hadronic processes. The
proton-(anti)proton cross sections are described with good agreement with data
and in a way consistent with the unitarity bound. The elastic scattering
amplitude is calculated at momentum transfer $t$ different from zero,
introducing two distinct ansatze for the proton impact factor. The elastic
differential cross section is obtained at small $t$ approximation and compared
with the data.

</DOC>
<DOC>
<DOCNO> 69129 </DOCNO>
Form Factors and QCD in Spacelike and Timelike Region


  We analyze the basic hard exclusive processes: \pi\gamma*\gamma - transition,
pion and nucleon electromagnetic form factors, and discuss the analytic
continuation of QCD formulas from the spacelike q^2<0 to the timelike region
q^2 >0 of the relevant momentum transfers. We describe the construction of the
timelike version of the coupling constant \alpha_s. We show that due to the
analytic continuation of the collinear logarithms each eigenfunction of the
evolution equation acqiures a phase factor and investigate the resulting
interference effects which are shown to be very small. We found no sources for
the K-factor-type enhancements in the perturbative QCD contribution to the
hadronic form factors. To study the soft part of the pion electromagnetic form
factor, we use a QCD sum rule inspired model and show that there are
non-canceling Sudakov double logarithms which result in a K-factor-type
enhancement in the timelike region.

</DOC>
<DOC>
<DOCNO> 119811 </DOCNO>
A Fundamental Relation Between Supermassive Black Holes and Their Host


  The masses of supermassive black holes correlate almost perfectly with the
velocity dispersions of their host bulges, M(BH) ~ sigma^alpha, where alpha
=4.8 +/- 0.5$. The relation is much tighter than the relation between M(BH) and
bulge luminosity, with a scatter no larger than expected on the basis of
measurement error alone. Black hole masses estimated by Magorrian et al. (1998)
lie systematically above the M(BH)-sigma relation defined by more accurate mass
estimates, some by as much as two orders of magnitude. The tightness of the
M(BH)-sigma relation implies a strong link between black hole formation and the
properties of the stellar bulge.

</DOC>
<DOC>
<DOCNO> 11998 </DOCNO>
2D XY Ordering in Striped Cu-O Planes in Underdoped Bi-2212


  It was discussed the possibility of determination of 2D XY ordering
temperature (Berezinskii-Kosterlitz-Thouless temperature) in striped Cu-O
planes for quasi-two dimensional HTS with the semiconducting behavior of
out-of-plane resistivity in normal state. From the results of the resistivity
measurements for samples of underdoped Bi-2212 the values of 2D XY ordering
temperature were found out. Its are compared with the results of the
measurements of frequency dependent conductivity. It is shown that these both
results give the value of 2D XY ordering temperature ~62 K for samples with
Tc=74 K and verify the importance of taken into account two dimensional
superconducting fluctuations at T>Tc.

</DOC>
<DOC>
<DOCNO> 10387 </DOCNO>
Effect of the additional second neighbor hopping on the spin dynamics in


  The effect of the additional second neighbor hopping t' on the spin dynamics
in the t-J model is studied within the fermion-spin theory. Although the
additional second neighbor hopping t' is systematically accompanied with the
reduction of the dynamical spin structure factor and susceptibility, the
qualitative behaviors of the dynamical spin structure factor and susceptibility
are the same as in the case of t-J model. It is also shown that the integrated
dynamical spin structure factor is almost t' independent in the underdoped
regime.

</DOC>
<DOC>
<DOCNO> 11638 </DOCNO>
Inattainability of Carnot efficiency in the Brownian heat engine


  We discuss the reversibility of Brownian heat engine.
We perform asymptotic analysis of Kramers equation on B\"uttiker-Landauer
system and show quantitatively that Carnot efficiency is inattainable even in a
fully overdamping limit.
The inattainability is attributed to the inevitable irreversible heat flow
over the temperature boundary.

</DOC>
<DOC>
<DOCNO> 121642 </DOCNO>
NGC 4340: Double Bar + Fossil Nuclear Ring


  NGC 4340 is a double-barred SB0 galaxy in the Virgo cluster (Wozniak et al.
1995). Here, we present evidence that this galaxy also posseses a luminous
stellar nuclear ring of relatively old stars with little or no gas. The ring
lies just outside the inner bar, at the probable inner inner Lindblad resonance
(IILR) of the outer bar. Careful inspection of the isophotes and unsharp masks
shows that the two bars are slightly misaligned, which suggests they may be
independently rotating.

</DOC>
<DOC>
<DOCNO> 122139 </DOCNO>
The Impact of Resolution on Observed HII Region Properties from WFPC2


  Two continuum subtracted H-alpha HST frames of M101 are used to determine the
positions, angular sizes and absolute fluxes of 237 HII regions using a
semi-automated technique. From these we have constructed the luminosity and
diameter distribution functions.
 We repeat this process on the images after artificially reducing the linear
resolution to that typically obtained with ground based imaging. We find
substantial differences in the luminosity function and diameter distribution.
The measured internal properties, such as central surface brightness and radial
gradient are dominated by the PSF at linear resolutions less than roughly 40 pc
FWHM. From the ground such resolutions are currently only obtainable for the
nearest galaxies.
 We find evidence for two regimes of clustering of the HII regions and diffuse
emission, suggesting two different regimes of star formation in late type
spiral galaxies. This property in combination with the blending that occurs at
ground based resolutions might be responsible for the break in the luminosity
function which is usually found at log L=38.6 erg/s.
 From the high resolution HST data we find a luminosity function slope of
alpha=-1.74+/-0.08. We also observe a flattening at luminosities log L<36.7
erg/s. For the diameter distribution we find a characteristic scale of D0=29.2
pc from an exponential fit. However, a scale free power law with index
beta=-2.84+/-0.16 provides a better fit to the data.

</DOC>
<DOC>
<DOCNO> 116711 </DOCNO>
The Theory of Gravitation in the Space - Time with Fractal Dimensions


  In the space and the time with a fractional dimensions the Lorents
transformations fulfill only as a good approach and become exact only when
dimensions are integer. So the principle of relativity (it is exact when
dimensions are integer) may be treated also as a good approximation and may
remain valid (but modified) in case of small fractional corrections to integer
dimensions of time and space. In this paper presented the gravitation field
theory in the fractal time and space (based on the fractal theory of time and
space developed by author early). In the theory are taken into account the
alteration of Lorents transformations for case including $v=c$ and are
described the real gravitational fields with spin equal 2 in the fractal time
defined on the Riemann or Minkowski measure carrier. In the theory introduced
the new "quasi-spin", given four equations for gravitational fields (with
different "quasi spins" and real and imaginary energies). For integer
dimensions the theory coincide with Einstein GR or Logunov- Mestvirichvili
gravitation theory.

</DOC>
<DOC>
<DOCNO> 39741 </DOCNO>
Solar panels as air Cherenkov detectors for extremely high energy cosmic


  Increasing interest towards the observation of the highest energy cosmic rays
has motivated the development of new detection techniques. The properties of
the Cherenkov photon pulse emitted in the atmosphere by these very rare
particles indicate low-cost semiconductor detectors as good candidates for
their optical read-out.
   The aim of this paper is to evaluate the viability of solar panels for this
purpose. The experimental framework resulting from measurements performed with
suitably-designed solar cells and large conventional photovoltaic areas is
presented.
 A discussion on the obtained and achievable sensitivities follows.

</DOC>
<DOC>
<DOCNO> 11511 </DOCNO>
Enhancement of Kondo Temperature in Nanometer-Size Point Contacts


  Point-contact spectroscopy is applied to study the energy dependence of
paramagnetic impurities in noble metals. The samples are in the form of the
so-called "mechanically controllable break-junctions" where the investigated
piece of alloy makes a nanowire connecting two bulk electrodes.The lateral
dimensions of the bridge are of the order of a few nm and can be continuously
changed. Three qualitative dependences manifest the size effect while
decreasing the contact diameter: 1) Intensity of Kondo peak due to Kondo
scattering in point-contact spectra decreases slower than the nonlinearities
due to phonon scatterings, 2) The width of the Kondo peak becomes broder, and
3) Due to the Zeeman energy, the splitting of Kondo peak in external and
internal (for a spin glass) fields, is suppressed. Explanation of the phenomena
is given in terms of the theory of Zarand and Udvardi where the local density
of states (LDOS) of conduction electron fluctuates strongly inside a nanowire
due to interference of electronic states. Since Kondo effect is a local probe
of LDOS, the impurities located close to the maxima of LDOS show the increase
of the Kondo temperature and give the primary contribution to the contact
resistance.

</DOC>
<DOC>
<DOCNO> 70041 </DOCNO>
Photoproduction of Charmonia and Total Charmonium-Proton Cross Sections


  Elastic virtual photoproduction cross sections gamma^*p -> J/psi(psi')p and
total charmonium-nucleon cross sections for J/psi, psi' and chi states are
calculated in a parameter free way with the light-cone dipole formalism and the
same input: factorization in impact parameters, light-cone wave functions for
the gamma^* and the charmonia, and the universal phenomenological dipole cross
section which is fitted to other data. The charmonium wave functions are
calculated with four known realistic potentials, and two models for the dipole
cross section are tested. Very good agreement with data for the cross section
of charmonium photoproduction is found in a wide range of s and Q^2. The
inclusion of the Melosh spin rotation increases the psi' photoproduction rate
by a factor 2-3 and removes previously observed discrepancies in the psi' to
J/psi ratio in photoproduction. We also calculate the charmonium-proton cross
sections whose absolute values and energy dependences are found to correlate
strongly with the sizes of the states.

</DOC>
<DOC>
<DOCNO> 169881 </DOCNO>
Discrete Moyal-type Representations for a Spin


  In Moyal's formulation of quantum mechanics, a quantum spin s is described in
terms of continuous symbols, i.e. by smooth functions on a two-dimensional
sphere. Such prescriptions to associate operators with Wigner functions, P- or
Q-symbols, are conveniently expressed in terms of operator kernels satisfying
the Stratonovich-Weyl postulates. In analogy to this approach, a discrete Moyal
formalism is defined on the basis of a modified set of postulates. It is shown
that appropriately modified postulates single out a well-defined set of kernels
which give rise to discrete symbols. Now operators are represented by functions
taking values on (2s+1)(2s+1) points of the sphere. The discrete symbols
contain no redundant information, contrary to the continuous ones. The
properties of the resulting discrete Moyal formalism for a quantum spin are
worked out in detail and compared to the continuous formalism, and it is
illustrated by the example of a spin 1/2.

</DOC>
<DOC>
<DOCNO> 150974 </DOCNO>
Orientifolds and twisted boundary conditions


  It is argued that the T-dual of a crosscap is a combination of an O+ and an
O- orientifold plane. Various theories with crosscaps and D-branes are
interpreted as gauge-theories on tori obeying twisted boundary conditions.
Their duals live on orientifolds where the various orientifold planes are of
different types. We derive how to read off the holonomies from the positions of
D-branes in the orientifold background. As an application we reconstruct some
results from a paper by Borel, Friedman and Morgan for gauge theories with
classical groups, compactified on a 2-- or 3--torus with twisted boundary
conditions.

</DOC>
<DOC>
<DOCNO> 85185 </DOCNO>
Energetic Cosmic Rays observed by the resonant gravitational wave


  Cosmic ray showers interacting with the resonant mass gravitational wave
antenna NAUTILUS have been detected. The experimental results show large
signals at a rate much greater than expected. The largest signal corresponds to
an energy release in NAUTILUS of 87 TeV. We remark that a resonant mass
gravitational wave detector used as particle detector has characteristics
different from the usual particle detectors, and it could detect new features
of cosmic rays. Among several possibilities, one can invoke unexpected
behaviour of superconducting Aluminium as particle detector, producing enhanced
signals, the excitation of non-elastic modes with large energy release or
anomalies in cosmic rays (for instance, the showers might include exotic
particles as nuclearites or Q-balls). Suggestions for explaining these
observations are solicited.

</DOC>
<DOC>
<DOCNO> 150790 </DOCNO>
K\"ahler Potential of Moduli Space in Large Radius Region of Calabi-Yau


  We study a kaehler potential K in the large radius region of a Calabi-Yau
d-fold M embedded in CP^{d+1}. It has a kaehler parameter t that describes a
deformation of the A-model moduli. Also the metric, curvature and hermitian
two-point functions in the large volume region are analyzed. We use a result of
our previous paper in the B-model of the mirror. We perform an analytic
continuation of a parameter to the large complex structure region. By
translating the result in the A-model side of M, we determine the K. The method
is not restricted to this specific model and we apply the recipe to complete
intersection Calabi-Yau cases.

</DOC>
<DOC>
<DOCNO> 68387 </DOCNO>
Treatment of Heavy Quarks in Deeply Inelastic Scattering


  We investigate a simplified version of the ACOT prescription for calculating
deeply inelastic scattering from Q^2 values near the squared mass M_H^2 of a
heavy quark to Q^2 much larger than M_H^2.

</DOC>
<DOC>
<DOCNO> 121033 </DOCNO>
Eros 2 proper motion survey for halo white dwarfs


  Since 1996 EROS 2 has surveyed 440 square degrees at high Galactic latitude
in order to search for high proper motion stars in the Solar neighbourhood. We
present here the analysis of 250 square degrees for which we have three years
of data. No object with halo-like kinematics has been detected. Using a
detailed Monte-Carlo simulation of the observations, we calculate our detection
efficiency for this kind of object and place constraints on their contribution
to various halo models. If 14 Gyr old, the halo cannot be made of more than 18%
of hydrogen white dwarfs (95% C.L.).

</DOC>
<DOC>
<DOCNO> 9704 </DOCNO>
Magnetotransport study of the charged stripes in high-T_c cuprates


  We present a study of the in-plane and out-of-plane magnetoresistance (MR) in
heavily-underdoped, antiferromagnetic YBa_{2}Cu_{3}O_{6+x}, which reveals a
variety of striking features. The in-plane MR demonstrates a "d-wave"-like
anisotropy upon rotating the magnetic field H within the ab plane. With
decreasing temperature below 20-25 K, the system acquires memory: exposing a
crystal to the magnetic field results in a persistent in-plane resistivity
anisotropy. The overall features can be explained by assuming that the CuO_2
planes contain a developed array of stripes accommodating the doped holes, and
that the MR is associated with the field-induced topological ordering of the
stripes.

</DOC>
<DOC>
<DOCNO> 102831 </DOCNO>
Fourier-Mukai Transform and Mirror Symmetry for D-Branes on Elliptic


  Fibrewise T-duality (Fourier-Mukai transform) for D-branes on an elliptic
Calabi-Yau three-fold $X$ is seen to have an expected adiabatic form for its
induced cohomology operation only when an appropriately twisted operation resp.
twisted charge is defined. Some differences with the case of $K3$ as well as
connections with the spectral cover construction for bundles on $X$ are pointed
out. In the context of mirror symmetry Kontsevich's association of line bundle
twists (resp. a certain 'diagonal' operation) with monodromies (esp. the
conifold monodromy) is made explicit and checked for two example models.
Interpreting this association as a relation between FM transforms and
monodromies, we express the fibrewise FM transform through known monodromies.
The operation of fibrewise duality as well as the notion of a certain index
relevant to the computation of the moduli space of the bundle is transported to
the sLag side. Finally the moduli space for D4-branes and its behaviour under
the FM transform is considered with an application to the spectral cover.

</DOC>
<DOC>
<DOCNO> 101571 </DOCNO>
Elliptic Islands on the Elliptical Stadium


  We investigate the existence of elliptic islands for a special family of
periodic orbits of a two-parameter family of maps corresponding to the billiard
problem on the elliptical stadium. The hyperbolic or elliptical character of
these orbits is also investigated. Depending on the parameters, we obtain upper
bounds of ellipticity for this special family as a lower bound for chaos. On a
different region of the parameter space, we can prove that there is no upper
bound for the existence of elliptic islands. The main results we use are
Birkhoff Normal Form and Moser's Twist Theorem.

</DOC>
<DOC>
<DOCNO> 121697 </DOCNO>
Rotation of the Disk of the Large Magellanic Cloud


  The rotation of the disk of the LMC is derived from the radial velocities of
975 carbon stars. The radial component of the disk's velocity ellipsoid is
sigma_R = 28 +- 14 km/s. The disk rotates with a true maximum circular velocity
of 79 km/s after correcting for asymmetric drift. For a typical submaximal
disk, the LMC's dark halo has a mass of 10 billion solar masses inside of 10
kpc. If the LMC microlensing lens population is halo of stars in the LMC, its
mass-to-light ratio is greater than 10.

</DOC>
<DOC>
<DOCNO> 123209 </DOCNO>
Can We Date Starbursts?


  Age dating starbursts is an exercise with many caveats. We attempt to
summarise a discussion session that was lead along a rather optimistic
guideline: the aim was to highlight that current age estimates, despite
undeniable uncertainties, do provide constraints on the physics of starbursts.
In many cases, better starburst theories will be needed before the improvement
of empirical timelines becomes crucial.

</DOC>
<DOC>
<DOCNO> 84981 </DOCNO>
(D-E)-dimensional brane worlds and de Rham distribution formalism:


  The proposed so far brane-world cosmological scenarios are concerned with
(D-1)-dimensional embeddings into the D-dimensional spacetime, besides, it is
supposed D=5 as a rule. However, it would be much more realistic to consider
our four-Universe as 4-shell or 3-brane inside, e.g., 10-dimensional spacetime.
In turn it immediately means that the theory of the $(D-D_E)$-dimensional
singular embeddings, where the number of extra dimensions $D_E > 1$, is needed.
Hence, the aim of this work is to provide such a theory: we construct the
rigorous general theory of the induced gravity on singular submanifolds. At
first, we perform the decomposition of the tangent bundle into the two
subbundles which will be associated later with external and visible (with
respect to some low-dimensional observer) parts of the high-$D$ manifold. Then
we go to physics and perform the split of the manifold (in addition to the
split of the tangent bundle) to describe both the induced internal geometry and
external as-a-whole dynamics of singular embeddings, assuming matter being
confined on the singular submanifold but gravity being propagated through the
high-$D$ manifold. With the use of the de Rham axiomatic approach to
delta-distributions we demonstrate that the four-Universe can be singularly
embedded only in five- and six-dimensional space so if we want to consider its
embedding in 10D then extra dimensions must be included as a product space
only. We discuss the revealed generic features of the theory such as the
multi-normal anisotropy, restrictions on an ambient space, reformulation of the
conserved gravitational stress-energy tensor problem, etc.

</DOC>
<DOC>
<DOCNO> 12932 </DOCNO>
Negative differential resistance in nanotube devices


  Carbon nanotube junctions are predicted to exhibit negative differential
resistance, with very high peak-to-valley current ratios even at room
temperature. We treat both nanotube p-n junctions and undoped
metal-nanotube-metal junctions, calculating quantum transport through the
self-consistent potential within a tight-binding approximation. The undoped
junctions in particular may be suitable for device integration.

</DOC>
<DOC>
<DOCNO> 10287 </DOCNO>
Thermodynamic picture of the glassy state


  A picture for thermodynamics of the glassy state is introduced. It assumes
that one extra parameter, the effective temperature, is needed to describe the
glassy state. This explains the classical paradoxes concerning the Ehrenfest
relations and the Prigogine-Defay ratio. As a second part, the approach
connects the response of macroscopic observables to a field change with their
temporal fluctuations, and with the fluctuation-dissipation relation, in a
generalized non-equilibrium way.

</DOC>
<DOC>
<DOCNO> 84373 </DOCNO>
Group Averaging and Refined Algebraic Quantization


  We review the framework of Refined Algebraic Quantization and the method of
Group Averaging for quantizing systems with first-class constraints. Aspects
and results concerning the generality, limitations, and uniqueness of these
methods are discussed.

</DOC>
<DOC>
<DOCNO> 12760 </DOCNO>
Double Exchange in Electron Doped Ca1-xYxMnO3 Manganites


  We have studied structural, magnetic and transport properties as a function
of temperature and magnetic field in the electron doped manganite YxCa1-xMnO3,
for 0<x<0.25. We found that in the paramagnetic regime, the magnetic
susceptibility, \chi, deviates substantially from a Curie-Weiss law for x>0.
With a simple model where antiferromagnetic (AF) superexchange and
ferromagnetic (FM) double exchange (DE) compete, we fit the experimental
\chi(x, T) obtaining parameter values which indicate that the FM-DE interaction
is about twice as intense as the AF interaction. In the ordered phase, the
H-dependence of the magnetization M(x,T) is explained in terms of magnetic
polarons. We propose that the displacement of the eg electrons (in the G-type
AF background) causes the alignement of the polaron with H. Signatures of
polaronic behavior were also found in the x and T dependence of the electric
resistivity.

</DOC>
<DOC>
<DOCNO> 71444 </DOCNO>
QCD Potentiology


  We review the connection between QCD and potential models of quarkonia in the
framework of effective field theories, with an emphasis on non-perturbative
methods such as lattice simulations. The static and heavy quark potentials are
introduced and the applicability of the non-relativistic and adiabatic
approximations are discussed. The roles of so-called hybrid potentials are
explored and we comment on the QCD analogue of the QED Lamb shift.

</DOC>
<DOC>
<DOCNO> 11540 </DOCNO>
Thermal conductivity of amorphous carbon thin films


  Thermal conductivities $\Lambda $ of amorphous carbon thin films are measured
in the temperatures range 80--400 K using the $3\omega $ method. Sample films
range from soft a-C:H prepared by remote-plasma deposition ($\Lambda = 0.20$ W
m$^{-1}$ K$^{-1}$ at room temperature) to amorphous diamond with a large
fraction of $sp^3$ bonded carbon deposited from a filtered-arc source ($\Lambda
= 2.2$ W m$^{-1}$ K$^{-1}$). Effective-medium theory provides a
phenomenological description of the variation of conductivity with mass
density. The thermal conductivities are in good agreement with the minimum
thermal conductivity calculated from the measured atomic density and
longitudinal speed of sound.

</DOC>
<DOC>
<DOCNO> 117599 </DOCNO>
Starbursts in barred spiral galaxies IV: On young bars and the formation


  The oxygen (O/H) and N/O abundance ratios along the bar of 16 barred spiral
starburst galaxies are determined using long-slit spectroscopy. The abundance
gradients and the spatial distribution of the ionized gas along the bar are
used to understand the role of bars in starburst galaxies.
  The oxygen abundance gradients are steeper than in normal barred galaxies,
while the intersects are low. This excludes the possibility that these are
chemically evolved galaxies rejuvenated by the effect of a bar. The
nitrogen-to-oxygen abundance gradients are flatter than the oxygen ones. But
N/O intersects are high, which rules out the possibility that a large quantity
of gas was recently funneled by a bar toward the center of a young galaxy.
Bars, therefore, cannot be at the origin of the bursts in the nuclei of our
sample galaxies.
  The oxygen and N/O abundance gradients are generally stronger in the bar than
in the disk and are linked together by a linear relation. This can be fully
explained in terms of star formation history: the gradients build up from the
inside out, becoming stronger as the oxygen and N/O abundances increase in the
bulge while staying low in the disk.
  In many of the sample galaxies, star formation occurs at one or both ends of
the bar. The low level of chemical enrichment in these regions suggests that
they recently experienced bar-triggered star formation: this is the only
visible effect of bars. Our analysis shows that bars probably appeared very
recently (a few 10^7 years) in the starburst galaxies, which are relatively
"young" galaxies still in the process of formation.(Abridged)

</DOC>
<DOC>
<DOCNO> 85587 </DOCNO>
Qualitative analysis of a scalar-tensor theory with exponential


  A qualitative analysis of a scalar-tensor cosmological model, with an
exponential potential for the scalar field, is performed. The phase diagram for
the flat case is constructed. It is shown that solutions with an initial and
final inflationary behaviour appear. The conditions for which the scenario
favored by supernova type Ia observations becomes an attractor in the space of
the solutions are established.

</DOC>
<DOC>
<DOCNO> 40390 </DOCNO>
A phenomenological description of $K\to\pi\pi\gamma$ magnetic


  A phenomenological analysis of $K\to \pi\pi\gamma$ ($K_L\to\pi^+\pi^-\gamma$
and $K^+\to\pi^+\pi^0\gamma$) with the direct emission photon is carried out
beyond the leading order in the chiral perturbation theory. We show that the
experimental evidence for the large photon energy dependence of the magnetic
amplitude in $K_L\to\pi^+\pi^-\gamma$ seems to indicate an interesting
consequence: vector meson dominance must be implemented at $O(p^4)$, which is
not a general feature of the chiral perturbation theory. The phenomenology of
$K^+\to\pi^+\pi^0\gamma$ is also analyzed using the same scheme.

</DOC>
<DOC>
<DOCNO> 13681 </DOCNO>
Theory and Applications of X-ray Standing Waves in Real Crystals


  Theoretical aspects of x-ray standing wave method for investigation of the
real structure of crystals are considered in this review paper. Starting from
the general approach of the secondary radiation yield from deformed crystals
this theory is applied to different concreat cases. Various models of deformed
crystals like: bicrystal model, multilayer model, crystals with extended
deformation field are considered in detailes. Peculiarities of x-ray standing
wave behavior in different scattering geometries (Bragg, Laue) are analysed in
detailes. New possibilities to solve the phase problem with x-ray standing wave
method are discussed in the review. General theoretical approaches are
illustrated with a big number of experimental results.

</DOC>
<DOC>
<DOCNO> 178479 </DOCNO>
Hartree-Fock-Bogoliubov for deformed neutron-rich nuclei


  The two-basis method to solve the HFB for deformed nuclei in coordinate space
is examined concerning the precision of the density tail. Small cutoff energies
are shown to give rise to ripples in the tail, whose wave length corresponds to
the cutoff momentum. More precise solutions require higher cutoff energies,
which result in HFB matrices of larger dimensions. To circumvent the difficulty
of the large dimension, we employ another method to solve the HFB ---the
natural-orbital method introduced originally for spherical nuclei--- to apply
it to deformed nuclei. The method can be successfully implemented with a
three-dimensional Cartesian mesh representation.

</DOC>
<DOC>
<DOCNO> 178776 </DOCNO>
Direct-decay properties of charge-exchange spin giant resonances


  An extended continuum-RPA approach is applied to describe direct-decay
properties of spin giant resonances in $^{208}$Bi and $^{90}$Nb. Partial
branching ratios for direct proton decay from these resonances are evaluated.
The branching ratio for $\gamma$-decay from the spin-dipole resonance to the
Gamow-Teller resonance (main peak) is estimated. The saturation-like behaviour
of the mean doorway-state spreading width in $^{208}$Pb is discussed in
connection with the branching ratio for direct proton decay from the
spin-monopole resonance and the Gamow-Teller strength distribution.

</DOC>
<DOC>
<DOCNO> 12900 </DOCNO>
Dynamic fitness landscapes: Expansions for small mutation rates


  We study the evolution of asexual microorganisms with small mutation rate in
fluctuating environments, and develop techniques that allow us to expand the
formal solution of the evolution equations to first order in the mutation rate.
Our method can be applied to both discrete time and continuous time systems.
While the behavior of continuous time systems is dominated by the average
fitness landscape for small mutation rates, in discrete time systems it is
instead the geometric mean fitness that determines the system's properties. In
both cases, we find that in situations in which the arithmetic (resp.
geometric) mean of the fitness landscape is degenerate, regions in which the
fitness fluctuates around the mean value present a selective advantage over
regions in which the fitness stays at the mean. This effect is caused by the
vanishing genetic diffusion at low mutation rates. In the absence of strong
diffusion, a population can stay close to a fluctuating peak when the peak's
height is below average, and take advantage of the peak when its height is
above average.

</DOC>
<DOC>
<DOCNO> 178579 </DOCNO>
Pion photo- and electroproduction and the partially-conserved axial


  The relevance of the axial current for pion production processes off the
nucleon with real or virtual photons is revisited. Employing the hypothesis of
a partially conserved axial current (PCAC), it is shown that, when all of the
relevant contributions are taken into account, PCAC does not provide any
additional constraint for threshold production processes that goes beyond the
Goldberger-Treiman relation. In particular, it is shown that pion
electroproduction processes at threshold cannot be used to extract any
information regarding the weak axial form factor. The relationships found in
previous investigations are seen to be an accident of the approximations
usually made in this context.

</DOC>
<DOC>
<DOCNO> 7694 </DOCNO>
Reentrant layering in rare gas adsorption: preroughening or premelting?


  The reentrant layering transitions found in rare gas adsorption on solid
substrates have conflictually been explained either in terms of preroughening
(PR), or of top layer melting-solidification phenomena. We obtain adsorption
isotherms of Lennard-Jones particles on an attractive substrate by off lattice
Grand Canonical Monte Carlo (GCMC) simulation, and reproduce reentrant
layering. Microscopic analysis, including layer-by-layer occupancies, surface
diffusion and pair correlations, confirms the switch of the top surface layer
from solid to quasi-liquid across the transition temperature. At the same time,
layer occupancy is found at each jump to switch from close to full to close to
half, indicating a disordered flat (DOF) surface and establishing preroughening
as the underlying mechanism. Our results suggest that top layer melting is
essential in triggering preroughening, which thus represents the threshold
transition to surface melting in rare gas solids.

</DOC>
<DOC>
<DOCNO> 120735 </DOCNO>
Cosmological Studies from Radio Source Samples


  I review some recent cosmological studies based on redshift surveys of radio
sources selected at low frequencies. The accretion rate onto the central black
hole is identified as the basis of a crude physical division of the
low-frequency population into two sub-populations: the first comprises
`Eddington-tuned' (high accretion rate) quasars and their torus-hidden
counterparts; the second comprises `starved quasars' like M87. There exist
remarkable similarities between the shapes and evolutionary behaviours of the
luminosity functions of radio sources and radio-quiet quasars; all luminous AGN
are $\sim300-$times rarer at epochs corresponding to $z \sim 0$ than at $z \sim
2.5$. I argue that any evidence that quasars were intrinsically rarer at $z
\sim 5$ than at $z \sim 2.5$ is as yet both tentative and indirect. A simple
calculation suggests that the radio source population has been over-looked as a
potentially important contributor to the entropy budget of the Universe. A
recent sub-mm survey of radio sources is used to demonstrate a connection
between the events which trigger jets and intense bursts of star formation, and
a close link between the histories of star formation and AGN activity is
proposed. I discuss the aims and methods of future large redshift surveys of
radio sources, emphasising the importance of dovetailing these with the
development of robust physical models for radio sources and their
epoch-dependent environments.

</DOC>
<DOC>
<DOCNO> 10111 </DOCNO>
Strong Effects of Weak Localization in Charge Density Wave/Normal Metal


  Collective transport through a multichannel disordered conductor in contact
with charge-density-wave electrodes is theoretically investigated. The
statistical distribution function of the threshold potential for charge-density
wave sliding is calculated by random matrix theory. In the diffusive regime
weak localization has a strong effect on the sliding motion.

</DOC>
<DOC>
<DOCNO> 118083 </DOCNO>
The Final Fate of Coalescing Compact Binaries: From Black Hole to Planet


  Coalescing compact binaries are thought to be involved in a wide variety of
astrophysical phenomena. In particular, they are important sources of
gravitational radiation for both ground-based and space-based
laser-interferometer detectors, and they may be sources of supernova explosions
or gamma-ray bursts. Mergers of two white dwarfs may produce neutron stars with
peculiar properties, including perhaps millisecond radio pulsars sometimes
accompanied by planets (as observed in PSR 1257+12). According to a widely held
belief, the coalescence of two neutron stars should produce a rapidly rotating
black hole surrounded by an accretion disk or torus, but this is by no means
certain. This review paper focuses on the final hydrodynamic coalescence and
merger of double neutron stars and double white dwarfs, and addresses the
question of the nature of the final merger products.

</DOC>
<DOC>
<DOCNO> 101259 </DOCNO>
Holomorphic Disks and the Chord Conjecture


  We prove (a weak version of) Arnold's Chord Conjecture using Gromov's
``classical'' idea in to produce holomorphic disks with boundary on a
Lagrangian submanifold.

</DOC>
<DOC>
<DOCNO> 13632 </DOCNO>
Detecting the Kondo screening cloud around a quantum dot


  A fundamental prediction of scaling theories of the Kondo effect is the
screening of an impurity spin by a cloud of electrons spread out over a
mesoscopic distance. This cloud has never been observed experimentally.
Recently, aspects of the Kondo effect have been observed in experiments on
quantum dots embedded in quantum wires. Since the length of the wire may be of
order the size of the screening cloud, such systems provide an ideal
opportunity to observe it. We point out that persistent current measurements in
a closed ring provide a conceptually simple way of detecting this fundamental
length scale.

</DOC>
<DOC>
<DOCNO> 7649 </DOCNO>
Computer Simulations of Friction, Lubrication and Wear


  An overview of computer simulations of tribology is presented. The chapter
begins with a brief overview of simulation techniques and the special
requirements for simulations of tribological processes. Then simple
one-dimensional models of friction between crystalline surfaces are introduced
to illustrate general features of friction, such as the importance of
metastability and the effect of commensurability. Next two- and
three-dimensional studies of dry sliding between crystalline surfaces are
described, and compared to scanning probe experiments and measurements of the
friction on adsorbed monolayers. Lubrication is then discussed, starting from
thick films and describing the breakdown in bulk hydrodynamics as the thickness
of the lubricant decreases to molecular scales. Deviations from the usual
no-slip boundary condition are quantified and the onset of solid behavior in
molecularly thick films is described. The possibility that solidification of
thin layers of adventitious carbon is responsible for the prevalence of static
friction is explored. The final sections describe stick-slip motion,
tribochemical reactions, machining, and the evolution of microstructure in
sliding contacts.

</DOC>
<DOC>
<DOCNO> 9286 </DOCNO>
Partition noise and statistics in the fractional quantum Hall effect


  A microscopic theory of current partition in fractional quantum Hall liquids,
described by chiral Luttinger liquids, is developed to compute the noise
correlations, using the Keldysh technique. In this Hanbury-Brown and Twiss
geometry, at Laughlin filling factor \nu=1/3, the real time noise correlator
exhibits oscillations which persist over larger time scales than that of an
uncorrelated Hall fluid. The zero frequency noise correlations are negative at
filling factor 1/3 as for bare electrons (anti-bunching), but are strongly
reduced in amplitude. These correlations become positive (bunching) for \nu\leq
1/5, suggesting a tendency towards bosonic behavior.

</DOC>
<DOC>
<DOCNO> 85560 </DOCNO>
Torsion waves in metric-affine field theory


  The approach of metric-affine field theory is to define spacetime as a real
oriented 4-manifold equipped with a metric and an affine connection. The 10
independent components of the metric tensor and the 64 connection coefficients
are the unknowns of the theory. We write the Yang-Mills action for the affine
connection and vary it both with respect to the metric and the connection. We
find a family of spacetimes which are stationary points. These spacetimes are
waves of torsion in Minkowski space. We then find a special subfamily of
spacetimes with zero Ricci curvature; the latter condition is the Einstein
equation describing the absence of sources of gravitation. A detailed
examination of this special subfamily suggests the possibility of using it to
model the neutrino. Our model naturally contains only two distinct types of
particles which may be identified with left-handed neutrinos and right-handed
antineutrinos.

</DOC>
<DOC>
<DOCNO> 12790 </DOCNO>
Effects of an in-plane magnetic field on c-axis sum rule and superfluid


  In layered cuprates, the application of an in-plane magnetic field $({\bf
H})$ changes the c-axis optical sum rule and superfluid density $\rho_{s}$. For
pure incoherent c-axis coupling, ${\bf H}$ has no effect on either quantities
but it does if an additional coherent component is present. For the coherent
contribution, different characteristic variations on ${\bf H}$ and on
temperature result from the constant part $(t_{\perp})$ of the hopping matrix
element and from the part $(t_{\phi})$ which has zero on the diagonal of the
Brillouin zone. Only the constant part $(t_{\perp})$ leads to a dependence on
the direction of ${\bf H}$ as well as on its magnitude.

</DOC>
<DOC>
<DOCNO> 116865 </DOCNO>
Beam Emittance Measurements for the Low-Energy Demonstration Accelerator


  The Low-Energy Demonstration Accelerator (LEDA) radio-frequency quadrupole
(RFQ) is a 100% duty factor (CW) linac that delivers >100 mA of H+ beam at 6.7
MeV. The 8-m-long, 350-MHz RFQ structure accelerates a dc, 75-keV, 110-mA H+
beam from the LEDA injector with >90% transmission. LEDA [1,2] consists of a
75-keV proton injector, 6.7-MeV, 350-MHz CW RFQ with associated high-power and
low-level rf systems, a short high-energy beam transport (HEBT) and high-power
(670-kW CW) beam stop. The beam emittance is inferred from wire scanner
measurements of the beam profile at a single location in the HEBT. The beam
profile is measured as a function of the magnetic field gradient in one of the
HEBT quadrupoles. As the gradient is changed the spot size passes through a
transverse waist. Measurements are presented for peak currents between 25 and
100 mA.

</DOC>
<DOC>
<DOCNO> 117350 </DOCNO>
Resonant capture, counter-rotating disks, and polar rings


  We suggest that polar rings and/or counter-rotating disks in flattened
galaxies can be formed from stars captured at the Binney resonance, where the
rate of precession of the angular momentum vector of a disk star equals the
pattern speed of a triaxial halo. If the halo pattern speed is initially
retrograde and slowly decays to zero, stars can be trapped as the Binney
resonance sweeps past them, and levitated into polar orbits. If the halo
pattern speed is initially retrograde and slowly changes to prograde, trapped
stars can evolve from prograde to retrograde disk orbits. The stellar
components of polar rings formed by this process should consist of two equal,
counter-rotating star streams.

</DOC>
<DOC>
<DOCNO> 170426 </DOCNO>
Experiments towards Falsification of Noncontextual Hidden Variable


  We present two experiments testing the hypothesis of noncontextual hidden
variables (NCHV's). The first one is based on observation of two-photon
pseudo-Greenberger-Horne-Zeilinger correlations, with two of the originally
three particles mimicked by the polarization degree of freedom and the spatial
degree of freedom of a single photon. The second one, a single-photon
experiment, utilizes the same trick to emulate two particle correlations, and
is an "event ready" test of a Bell-like inequality, derived from the
noncontextuality assumption. Modulo fair sampling, the data falsify NCHV's.

</DOC>
<DOC>
<DOCNO> 11705 </DOCNO>
Non-Fermi liquid angle resolved photoemission lineshapes of Li0.9Mo6O17


  A recent letter by Xue et al. (PRL v.83, 1235 ('99)) reports a Fermi-Liquid
(FL) angle resolved photoemission (ARPES) lineshape for quasi one-dimensional
Li0.9Mo6O17, contradicting our report (PRL v.82, 2540 ('99)) of a non-FL
lineshape in this material. Xue et al. attributed the difference to the
improved angle resolution. In this comment, we point out that this reasoning is
flawed. Rather, we find that their data have fundamental differences from other
ARPES results and also band theory.

</DOC>
<DOC>
<DOCNO> 169819 </DOCNO>
Comment on Mohrhoff's "What quantum mechanics is trying to tell us"


  Mohrhoff proposes using the Aharonov-Bergmann-Lebowitz (ABL) rule for
time-symmetric ``objective'' (meaning non-epistemic) probabilities
corresponding to the possible outcomes of not-actually-performed measurements
between specified pre- and post-selection measurement outcomes. It is
emphasized that the ABL rule was formulated on the assumption that such
intervening measurements are actually made and that it does not necessarily
apply to counterfactual situations. The exact nature of the application of the
ABL rule considered by Mohrhoff is made explicit and is shown to fall short of
his stated counterfactual claim.

</DOC>
<DOC>
<DOCNO> 68434 </DOCNO>
Determining the quantum numbers of excited heavy mesons


  We discuss the decays X^* -> Xe^+e^- (``Dalitz decays'') of excited heavy
mesons into their ground states and an electron-positron pair. We argue that
the measurement of the invariant mass spectrum of the lepton pair gives clear
indication on the quantum numbers of the excited meson and thus provides an
experimental test of the quark model predictions.

</DOC>
<DOC>
<DOCNO> 70965 </DOCNO>
A Tale of Two and Three Bodies


  This presentation is a concise teaser for the Effective Field Theory (EFT) of
two and three nucleon systems as it emerged in the last three years, using a
lot of words and figures, and a few cheats.

</DOC>
<DOC>
<DOCNO> 152088 </DOCNO>
Radiatively Induced Lorentz and CPT Violation in Schwinger Constant


  The Schwinger proper-time method is an effective calculation method,
explicitly gauge invariant and nonperturbative. We make use of this method to
investigate the radiatively induced Lorentz and CPT-violating effects in
quantum electrodynamics when an axial vector interaction term is introduced in
the fermionic sector. The induced Lorentz and CPT-violating Chern-Simons term
coincides with the one obtained using a covariant derivative expansion but
differs from the result usually obtained in other regularization schemes. A
possible ambiguity in the approach is also discussed.

</DOC>
<DOC>
<DOCNO> 68367 </DOCNO>
Collisional Energy Loss of Fast Charged Particles in Relativistic


  Following an argument by Kirzhnits we rederive an exact expression for the
energy loss of a fast charged particle in a relativistic plasma using the
quantum field theoretical language. We compare this result to perturbative
calculations of the collisional energy loss of an energetic electron or muon in
an electron-positron plasma and of an energetic parton in the quark-gluon
plasma.

</DOC>
<DOC>
<DOCNO> 150995 </DOCNO>
Crosscaps, Boundaries and T-Duality


  Open descendants with boundaries and crosscaps of non-trivial automorphism
type are studied. We focus on the case where the bulk symmetry is broken to a
Z_2 orbifold subalgebra. By requiring positivity and integrality for the open
sector, we derive a unique crosscap of automorphism type g \in Z_2 and a
corresponding g-twisted Klein bottle for a charge conjugation invariant. As a
specific example, we use T-duality to construct the descendants of the true
diagonal invariant with symmetry preserving crosscaps and boundaries.

</DOC>
<DOC>
<DOCNO> 71941 </DOCNO>
Domain walls of high-density QCD


  We show that in very dense quark matter there must exist metastable domain
walls where the axial U(1) phase of the color-superconducting condensate
changes by 2pi. The decay rate of the domain walls is exponentially suppressed
and we compute it semiclassically. We give an estimate of the critical chemical
potential above which our analysis is under theoretical control.

</DOC>
<DOC>
<DOCNO> 80797 </DOCNO>
Cost of the Generalised Hybrid Monte Carlo Algorithm for Free Field


  We study analytically the computational cost of the Generalised Hybrid Monte
Carlo (GHMC) algorithm for free field theory. We calculate the Metropolis
acceptance probability for leapfrog and higher-order discretisations of the
Molecular Dynamics (MD) equations of motion. We show how to calculate
autocorrelation functions of arbitrary polynomial operators, and use these to
optimise the GHMC momentum mixing angle, the trajectory length, and the
integration stepsize for the special cases of linear and quadratic operators.
We show that long trajectories are optimal for GHMC, and that standard HMC is
more efficient than algorithms based on Second Order Langevin Monte Carlo
(L2MC), sometimes known as Kramers Equation. We show that contrary to naive
expectations HMC and L2MC have the same volume dependence, but their dynamical
critical exponents are z = 1 and z = 3/2 respectively.

</DOC>
<DOC>
<DOCNO> 10229 </DOCNO>
Nanosized patterns as reference structures for macroscopic transport


  This paper studies the striking correlation between nanosized structural
patterns in YBCO films and macroscopic transport current. A nanosized network
of parallel Josephson junctions laced by insulating dislocations is almost
mimicking the grain boundary structural network. It contributes to the
macroscopic properties and accounts for the strong intergranular pinning across
the film in the intermediate temperature range. The correlation between the two
networks enables to find out an outstanding scaling law in the (Jc,B) plane and
to determine meaningful parameters concerning the matching between the vortex
lattice and the intergranular defect lattice. Two asymptotic behaviors of the
pinning force below the flux flow regime are checked: the corresponding vortex
phases are clearly individuated.

</DOC>
<DOC>
<DOCNO> 120995 </DOCNO>
Halo and Relic Sources in Clusters of Galaxies


  New images of 7 radio halos and relics, obtained with the Very Large Array at
20 or 90 cm, are presented here. The existence of a cluster-wide radio halo in
the clusters A 665 and CL 0016+16 is confirmed. Both these clusters share the
properties of the other clusters with radio halos, i.e. are luminous in X-rays,
have high temperature, and show recent merger processes. No diffuse sources are
detected in a sample of clusters showing at least a tailed radio galaxy within
300 kpc from the cluster center, indicating that the connection between tailed
radio galaxies and halos is not relevant. For these clusters we give limits to
the surface brightness and to the angular size of possible undetected diffuse
sources.

</DOC>
<DOC>
<DOCNO> 99787 </DOCNO>
Locally trivial quantum vector bundles and associated vector bundles


  We define locally trivial quantum vector bundles (QVB) and QVB associated to
locally trivial quantum principal fibre bundles. There exists a differential
structure on the associated vector bundle coming from the differential
structure on the principal bundle, which allows to define connections on the
associated vector bundle associated to connections on the principal bundle.

</DOC>
<DOC>
<DOCNO> 12985 </DOCNO>
Analytic approach to the one-dimensional spin-Peierls system in the


  We use the two cut-off renormalization group (RG) method to study the
spin-Peierls model in one-dimension for the entire phonon frequency range. We
integrate out the phonon and solve the effective Fermion system via mean field
and RG methods. We make use of the symmetry that the Neel, dimerization, and
spin current order parameters form an SU(2) triplet based on resolving the
Fermion into left and right movers. We present the phase diagram and discuss
its implications for the organic charge-transfer salt (TMTTF)$_2$PF$_6$.

</DOC>
<DOC>
<DOCNO> 71400 </DOCNO>
Scalar Field Dark Matter, Cross Section and Planck-Scale Physics


  In recent papers we have proposed that the dark matter of the Universe could
be from scalar field origin. In this letter, we find that if the scale of
renormalization of the model is of order of the Planck Mass, then a scalar
field $\Phi $ endowed with the scalar potential $V=V_{o}[\cosh {(\lambda
\sqrt{\kappa_{0}}\Phi)}-1] can be a reliable model for dark matter in galaxies.
The predicted scattering cross section fits the value required for
self-interacting dark matter and the additional degree of freedom of the theory
is of order of hundreds of TeV.

</DOC>
<DOC>
<DOCNO> 102801 </DOCNO>
Closedness of the Space of AHE Metrics on 4-Manifolds


  See comment above.

</DOC>
<DOC>
<DOCNO> 39829 </DOCNO>
Measurement of the Lifetime of the Tau Lepton


  The tau lepton lifetime is measured with the L3 detector at LEP using the
complete data taken at centre-of-mass energies around the Z pole resulting in
tau_tau = 293.2 +/- 2.0 (stat) +/- 1.5 (syst) fs. The comparison of this result
with the muon lifetime supports lepton universality of the weak charged current
at the level of six per mille. Assuming lepton universality, the value of the
strong coupling constant, alpha_s is found to be alpha_s(m_tau^2) = 0.319 +/-
0.015(exp.) +/- 0.014 (theory).

</DOC>
<DOC>
<DOCNO> 11002 </DOCNO>
Interacting electrons in a nearly straight quantum wire


  The conductance threshold of a clean nearly straight quantum wire in which a
single electron is bound is studied. This exhibits spin-dependent conductance
anomalies on the rising edge to the first conductance plateau, near
G=0.25(2e^{2}/h) and G=0.7(2e^{2}/h), related to a singlet and triplet
resonances respectively. We show that the problem may be mapped on to an
Anderson-type of Hamiltonian and calculate the energy dependence of the energy
parameters in the resulting model.

</DOC>
<DOC>
<DOCNO> 118760 </DOCNO>
The Generation of Magnetic Fields Through Driven Turbulence


  We have tested the ability of driven turbulence to generate magnetic field
structure from a weak uniform field using three dimensional numerical
simulations of incompressible turbulence. We used a pseudo-spectral code with a
numerical resolution of up to $144^3$ collocation points. We find that the
magnetic fields are amplified through field line stretching at a rate
proportional to the difference between the velocity and the magnetic field
strength times a constant. Equipartition between the kinetic and magnetic
energy densities occurs at a scale somewhat smaller than the kinetic energy
peak. Above the equipartition scale the velocity structure is, as expected,
nearly isotropic. The magnetic field structure at these scales is uncertain,
but the field correlation function is very weak. At the equipartition scale the
magnetic fields show only a moderate degree of anisotropy, so that the typical
radius of curvature of field lines is comparable to the typical perpendicular
scale for field reversal. In other words, there are few field reversals within
eddies at the equipartition scale, and no fine-grained series of reversals at
smaller scales. At scales below the equipartition scale, both velocity and
magnetic structures are anisotropic; the eddies are stretched along the local
magnetic field lines, and the magnetic energy dominates the kinetic energy on
the same scale by a factor which increases at higher wavenumbers. We do not
show a scale-free inertial range, but the power spectra are a function of
resolution and/or the imposed viscosity and resistivity. Our results are
consistent with the emergence of a scale-free inertial range at higher Reynolds
numbers.

</DOC>
<DOC>
<DOCNO> 100881 </DOCNO>
Infinitesimal aspects of the Laplace operator


  In the context of synthetic differential geometry, we study the Laplace
operator an a Riemannian manifold. The main new aspect is a neighbourhood of
the diagonal, smaller than the second neighbourhood usually required as support
for second order differential operators. The new neighbourhood has the property
that a function is affine on it if and only if it is harmonic.

</DOC>
<DOC>
<DOCNO> 71406 </DOCNO>
A precise determination of T_c in QCD from scaling


  Existing lattice data on the QCD phase transition are analyzed in
renormalized perturbation theory. In quenched QCD it is found that T_c scales
for lattices with only 3 time slices, and that T_c/Lambda_msbar=1.15 \pm 0.05.
A preliminary estimate in QCD with two flavours of dynamical quarks shows that
this ratio depends on the quark mass. For realistic quark masses we estimate
T_c/Lambda_msbar=0.49 \pm 0.02. We also investigate the equation of state in
quenched QCD at 1-loop order in renormalised perturbation theory.

</DOC>
<DOC>
<DOCNO> 80835 </DOCNO>
Order a improved renormalization constants


  We present non-perturbative results for the constants needed for on-shell
$O(a)$ improvement of bilinear operators composed of Wilson fermions. We work
at $\beta=6.0$ and 6.2 in the quenched approximation. The calculation is done
by imposing axial and vector Ward identities on correlators similar to those
used in standard hadron mass calculations. A crucial feature of the calculation
is the use of non-degenerate quarks. We also obtain results for the constants
needed for off-shell $O(a)$ improvement of bilinears, and for the scale and
scheme independent renormalization constants, (Z_A), (Z_V) and (Z_S/Z_P).
Several of the constants are determined using a variety of different Ward
identities, and we compare their relative efficacies. In this way, we find a
method for calculating $c_V$ that gives smaller errors than that used
previously. Wherever possible, we compare our results with those of the ALPHA
collaboration (who use the Schr\"odinger functional) and with 1-loop
tadpole-improved perturbation theory.

</DOC>
<DOC>
<DOCNO> 118951 </DOCNO>
The Optical Gravitational Lensing Experiment. A Hunt for Caustic


  In 1998 The Optical Gravitational Lensing Experiment (OGLE) successfully
implemented automated data reductions for QSO 2237+0305. Using a new image
subtraction method we achieved a differential photometry scatter of 1-5 % for
images A-D respectively. Combined with a time sampling of 1-2 times a week this
is sufficient for early detection of caustic crossings. Nearly real time
photometry of QSO 2237+0305 is available from the OGLE web site
http://www.astro.princeton.edu/~ogle/ogle2/huchra.html . During the 1999
observing season, the apparent V magnitude of the A, B, C and D images changed
by 0.50, 0.15, 0.65 and 0.35 mag, respectively. Most likely however, none of
the microlensing events involved a caustic crossing. The most rapid variation
was 0.25 mag in 30 days, observed for image C. The alert system will continue
to be active in the next observing season from late April until September 2000,
when OGLE suspends operation for an upgrade. Observations will resume for
season of 2001.

</DOC>
<DOC>
<DOCNO> 7847 </DOCNO>
Far-infrared reflectivity of Bi_2Sr_2CuO_6: the "anomalous Drude" model


  An optical "pseudogap" is usually assumed to open at low T in the "anomalous
Drude" absorption, which models the optical conductivity sigma(omega)
(proportional to omega-1) of HCTS by a linewidth Gamma (on the order of 1000
cm-1) varying with omega. In the sigma(omega) of BSCO, measured down to 10
cm-1, we have resolved instead: i) a normal Drude term with Gamma=35 cm-1 at 30
K, in very good agreement with transport data; ii) a strong band peaked in the
far infrared (FIR), likely due to bound charges, whose tail exhibits the
omega-1 dependence. As the FIR peak softens for decreasing T, it opens a
pseudogap-like depression in sigma(omega) accordingly to ordinary sum rules.

</DOC>
<DOC>
<DOCNO> 117940 </DOCNO>
Asymmetric, arc minute scale structures around NGC 1275


  ROSAT HRI observations show complicated substructure in the X-ray surface
brightness within $\sim$5 arcminutes around NGC 1275 -- the dominant galaxy of
the Perseus cluster. The typical amplitude of the variations is of the order of
30% of the azimuthally averaged surface brightness at a given distance from NGC
1275. We argue that this substructure could be related to the activity of NGC
1275 in the past. Bubbles of relativistic plasma, inflated by jets, be forced
to rise by buoyancy forces, mix with the ambient intracluster medium (ICM), and
then spread. Overall evolution of the bubble may resemble the evolution of a
hot bubble during a powerful atmospheric explosion. From a comparison of the
time scale of the bubble inflation to the rise time of the bubbles and from the
observed size of the radio lobes which displace the thermal gas, the energy
release in the relativistic plasma by the active nucleus of NGC 1275 can be
inferred. Approximate modeling implies a nuclear power output of the order of
$10^{45}$ erg s$^{-1}$ averaged over the last $\sim 3~10^7$ years. This is
comparable with the energy radiated in X-rays during the same epoch. Detailed
measurements of the morphology of the X-ray structure, the temperature and
abundance distributions with Chandra and XMM may test this hypothesis.

</DOC>
<DOC>
<DOCNO> 118973 </DOCNO>
On the late spectral types of cataclysmic variable secondaries


  We investigate why the spectral type of most cataclysmic variable (CV)
secondaries is significantly later than that of a ZAMS star with the same mean
density. Using improved stellar input physics, tested against observations of
low-mass stars at the bottom of the main sequence, we calculate the secular
evolution of CVs with low-mass donors. We consider sequences with different
mass transfer rates and with a different degree of nuclear evolution of the
donor prior to mass transfer. Systems near the upper edge of the gap ($P \sim 3
- 6$ h) can be reproduced by models with a wide range of mass transfer rates
from $1.5 \times 10^{-9} \msolyr$ to $10^{-8} \msolyr$. Evolutionary sequences
with a small transfer rate and donors that are substantially evolved off the
ZAMS (central hydrogen content $0.05-0.5$) reproduce CVs with late spectral
types above $P \simgr$ 6 h. Systems with the most discrepant (late) spectral
type should have the smallest donor mass at any given $P$. Consistency with the
period gap suggests that the mass transfer rate increases with decreasing donor
mass for evolved sequences above the period gap. In this case, a
single-parameter family of sequences with varying $\xc$ and increasing mass
transfer rate reproduces the full range of observed spectral types. This would
imply that CVs with such evolved secondaries dominate the CV population.

</DOC>
<DOC>
<DOCNO> 83124 </DOCNO>
Problem solving in ID-logic with aggregates: some experiments


  The goal of the LP+ project at the K.U.Leuven is to design an expressive
logic, suitable for declarative knowledge representation, and to develop
intelligent systems based on Logic Programming technology for solving
computational problems using the declarative specifications. The ID-logic is an
integration of typed classical logic and a definition logic. Different
abductive solvers for this language are being developed. This paper is a report
of the integration of high order aggregates into ID-logic and the consequences
on the solver SLDNFA.

</DOC>
<DOC>
<DOCNO> 13969 </DOCNO>
Using surface-wave spectroscopy to characterize tilt modes of a vortex


  A vortex in a condensate in a nonspherical trapping potential will in general
experience a torque. The torque will induce tilting of the direction of the
vortex axis. We observe this behavior experimentally and show that by applying
small distortions to the trapping potential, we can control the tilting
behaviour. By suppressing vortex tilt, we have been able to hold the vortex
axis along the line of sight for up to 15 seconds. Alternatively, we can induce
a 180 degree tilt, effectively reversing the charge on the vortex as observed
in the lab frame. We characterize the vortex non-destructively with a
surface-wave spectroscopic technique.

</DOC>
<DOC>
<DOCNO> 39763 </DOCNO>
Selex


  A summary of the path which lead to a high energy physics group at Instituto
de Fisica de la Universidad Autonoma de San Luis Potosi is presented. This
group is the result of the initial push made by Leon Lederman at the beginning
of the 80's.

</DOC>
<DOC>
<DOCNO> 84624 </DOCNO>
Cylindrical sources in full Einstein and Brans-Dicke gravity


  It was shown by Hiscock that the energy-momentum tensor commonly used to
model local cosmic strings in linearized Einstein gravity can be extended and
used in the full theory, obtaining a metric in the exterior of the source with
the same deficit angle. Here we show that this tensor is an exception within a
family for which a static solution does not exist in full Einstein nor in
Brans-Dicke gravity.

</DOC>
<DOC>
<DOCNO> 119195 </DOCNO>
The sign of temperature inhomogeneities deduced from time-distance


  Inhomogeneities in wave propagation conditions near and below the solar
surface have been detected by means of time-distance helioseismology. Here we
calculate the effect of temperature inhomogeneities on the travel times of
sound waves. A temperature increase, e.g. in active regions, not only increases
the sound speed but also lengthens the path along which the wave travels
because the expansion of the heated layers shifts the upper turning of the
waves upward. Using a ray tracing approximation we find that in many cases the
net effect of a temperature enhancement is an {\it increase} of the travel
times. We argue that the reduced travel times that are observed are caused by a
combination of magnetic fields in the active region and {\it reduced}
subsurface temperatures. Such a reduction may be related to the increased
radiative energy loss from small magnetic flux tubes.

</DOC>
<DOC>
<DOCNO> 178659 </DOCNO>
Charm meson scattering cross sections by pion and rho meson


  Using the local flavor SU(4) gauge invariance in the limit of vanishing
vector meson masses, we extend our previous study of charm meson scattering
cross sections by pion and rho meson, which is based only on the
pseudoscalar-pseudoscalar-vector meson couplings, to include also contributions
from the couplings among three vector mesons and among four particles. We find
that diagrams with light meson exchanges usually dominate the cross sections.
For the processes considered previously, the additional interactions lead only
to diagrams involving charm meson exchanges and contact interactions, and the
cross sections for these processes are thus not much affected. Nevertheless,
these additional interactions introduce new processes with light meson
exchanges and increase significantly the total scattering cross sections of
charm mesons by pion and rho meson.

</DOC>
<DOC>
<DOCNO> 10692 </DOCNO>
Penetration of Josephson vortices and measurement of the c-axis


  The first penetration field H_{J}(T) of Josephson vortices is measured
through the onset of microwave absorption in the locked state, in slightly
overdoped $\rm{Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta}}$ single crystals (T_{c} ~ 84
K). The magnitude of H_{J}(T) is too large to be accounted for by the first
thermodynamic critical field H_{c1}(T). We discuss the possibility of a
Bean-Livingston barrier, also supported by irreversible behavior upon flux
exit, and the role of defects, which relates H_{J}(T) to the c-axis penetration
depth $\lambda_{c}(T)$. The temperature dependence of the latter, determined by
a cavity perturbation technique and a theoretical estimate of the
defect-limited penetration field are used to deduce from H_{J}(T) the absolute
value of $\lambda_{c}(0)=(35 \pm 15) \mu m$.

</DOC>
<DOC>
<DOCNO> 120782 </DOCNO>
Optical Observations of the Black Hole Candidate XTE J1550-564 During


  We report optical monitoring of the soft X-ray transient XTE J1550-564 during
the 1999 season (4 January 1999 to 24 August 1999). The first optical
observations available in 1999 show that the peak ``re-flare'' brightness had
exceeded the peak brightness of the initial optical flare in September 1998 by
over half a magnitude. We compare the optical re-flare light curves with the
total X-ray flux, the power-law flux and disk flux light curves constructed
from the spectral fits to RXTE/PCA data made by Sobczak et al. (1999, 2000).
During the first 60 days of the observed optical re-flare, we find no
correspondence between the thermal component of the X-rays often associated
with a disk and the optical flux -- the former remains essentially flat whereas
the latter declines exponentially and exhibits three substantial dips. However,
the power law flux is anti-correlated with the optical dips, suggesting that
the optical flux may by up-scattered into the X-ray by the hot corona. Periodic
modulations were discovered during the final stage of the outburst (May to
June), with P=1.546+/-0.038 days, and during quiescence (July and August), with
P=1.540+/-0.008 days. The analysis of the combined data set reveals a strong
signal for a unique period at P=1.541+/-0.009 days, which we believe to be the
orbital period.

</DOC>
<DOC>
<DOCNO> 71573 </DOCNO>
"Free" Constituent Quarks and Dilepton Production in Heavy Ion


  An approach is suggested, invoking vitally the notion of constituent massive
quarks (valons) which can survive and propagate rather than hadrons (except of
pions) within the hot and dense matter formed below the chiral transition
temperature in course of the heavy ion collisions at high energies. This
approach is shown to be quite good for description of the experimentally
observed excess in dilepton yield at masses 250 MeV < M < 700 MeV over the
prompt resonance decay mechanism (CERES cocktail) predictions. In certain
aspects, it looks to be even more successful, than the conventional approaches:
it seems to match the data somewhat better at dilepton masses before the
two-pion threshold and before the rho-meson peak as well as at higher dilepton
masses (beyond the phi-meson one). The approach implies no specific assumptions
on the equation of state (EOS) or peculiarities of phase transitions in the
expanding nuclear matter.

</DOC>
<DOC>
<DOCNO> 102845 </DOCNO>
The Hodge structure of semiample hypersurfaces and a generalization of


  We solved the long-standing problem of describing the cohomology ring of
semiample hypersurfaces in complete simplicial toric varieties. Also, the
monomial-divisor mirror map is generalized to a map between the whole Picard
group and the space of infinitesimal deformations for a mirror pair of
Calabi-Yau hypersurfaces. This map is compatible with certain vanishing
limiting products of the subrings of the chiral rings, on which the ring
structure is related to a product of the roots of $A$-type Lie algebra.

</DOC>
<DOC>
<DOCNO> 101765 </DOCNO>
Singular lagrangians: some geometric structures along the Legendre map


  New geometric structures that relate the lagrangian and hamiltonian
formalisms defined upon a singular lagrangian are presented. Several vector
fields are constructed in velocity space that give new and precise answers to
several topics like the projectability of a vector field to a hamiltonian
vector field, the computation of the kernel of the presymplectic form of
lagrangian formalism, the construction of the lagrangian dynamical vector
fields, and the characterisation of dynamical symmetries.

</DOC>
<DOC>
<DOCNO> 39627 </DOCNO>
Confidence belts on bounded parameters


  We show that the unified method recently proposed by Feldman and Cousins to
put confidence intervals on bounded parameters cannot avoid the possibility of
getting null results. A modified bayesian approach is also proposed (although
not advocated) which ensures no null results and proper coverage.

</DOC>
<DOC>
<DOCNO> 70575 </DOCNO>
On the phase of the off-shell scattering amplitudes


  We prove that the phase of the partial wave amplitude does not depend on the
off-shell 4-momentum squared of one of the scattered particles.

</DOC>
<DOC>
<DOCNO> 116705 </DOCNO>
A Modified Theory Of Newtonian Mechanics


  A specific form of the inertial law is presented by which we can have some
deeper insight into the essence of mass and inertia. In this modified theory,
there is no need to keep the concept of absolute space and Newton's third law
as principles. By introducing a convenient form for gravitational law the
coupling constant G becomes a function of inertial parameters of the universe.

</DOC>
<DOC>
<DOCNO> 8794 </DOCNO>
Ab Initio Calculation of the Lattice Distortions induced by


  An ab initio study of the doping of alkali halide crystals (AX: A = Li, Na,
K, Rb; X = F, Cl, Br, I) by ns2 anions (Ag- and Cu-) is presented. Large active
clusters with 179 ions embedded in the surrounding crystalline lattice are
considered in order to describe properly the lattice relaxation induced by the
introduction of substitutional impurities. In all the cases considered, the
lattice distortions imply the concerted movement of several shells of
neighbors. The shell displacements are smaller for the smaller anion Cu-, as
expected. The study of the family of rock-salt alkali halides (excepting CsF)
allows us to extract trends that might be useful at a predictive level in the
study of other impurity systems. Those trends are presented and discussed in
terms of simple geometric arguments.

</DOC>
<DOC>
<DOCNO> 80822 </DOCNO>
Renormalons on the Lattice and the OPE for the plaquette: a status


  The first ten coefficients in the perturbative expansion of the plaquette in
Lattice SU(3) are computed both on a 8^4 and on a 24^4 lattice. They are shown
to be fully consistent with the growth dictated by the first IR Renormalon and
with the expected finite size effects on top of that. As already pointed out a
few years ago, this leads to a puzzling result on the smaller lattice: when the
contribution associated with the Renormalon is subtracted from Monte Carlo
measurements of the plaquette, what is left over does not scale (as expected)
as a^4, but as a^2. While the analysis is not yet complete on the larger
lattice, the implications of such a finding is discussed.

</DOC>
<DOC>
<DOCNO> 101096 </DOCNO>
Energy levels of neutral atoms via a new perturbation method


  The energy levels of neutral atoms supported by Yukawa potential, $V(r)=-Z
exp(-\alpha r)/r$, are studied, using both dimensional and dimensionless
quantities, via a new analytical methodical proposal (devised to solve for
nonexactly solvable Schrodinger equation). Using dimensionless quantities, by
scaling the radial Hamiltonian through $y=Zr$ and $\alpha^{'}=\alpha/Z$, we
report that the scaled screening parameter $\alpha^{'}$ is restricted to have
values ranging from zero to less than 0.4. On the other hand, working with the
scaled Hamiltonian enhances the accuracy and extremely speeds up the
convergence of the energy eigenvalues. The energy levels of several new
eligible scaled screening parameter $\alpha^{'}$ values are also reported.

</DOC>
<DOC>
<DOCNO> 100560 </DOCNO>
Normalizers of Operator Algebras and Reflexivity


  The set of normalizers between von Neumann (or, more generally, reflexive)
algebras A and B, (that is, the set of all operators x such that xAx* is a
subset of B and x*Bx is a subset of A) possesses `local linear structure': it
is a union of reflexive linear spaces. These spaces belong to the interesting
class of normalizing linear spaces, namely, those linear spaces U for which
UU*U is a subset of U. Such a space is reflexive whenever it is ultraweakly
closed, and then it is of the form U={x:xp=h(p)x, for all p in P}, where P is a
set of projections and h a certain map defined on P. A normalizing space
consists of normalizers between appropriate von Neumann algebras A and B.
Necessary and sufficient conditions are found for a normalizing space to
consist of normalizers between two reflexive algebras. Normalizing spaces which
are bimodules over maximal abelian selfadjoint algebras consist of operators
`supported' on sets of the form [f=g] where f and g are appropriate Borel
functions. They also satisfy spectral synthesis in the sense of Arveson.

</DOC>
<DOC>
<DOCNO> 117243 </DOCNO>
Infrared Fluorescence of Xe2 Molecules in beam-excited Xe Gas at high


  We report experimental results of proton- and electron-beam-induced
near-infrared (NIR) fluorescence in high-pressure Xe gas at room temperature.
The investigated wavelength band spans the range $0.7 \leq\lambda\leq 1.8
\mu{m}.$ In the previously unexplored range for $\lambda > 1.05 \mu{m}$ we have
detected a broad continuum NIR fluorescence at $\lambda\approx 1.3 \mu{m}$ that
shifts towards longer wavelengths as pressure is increased up to $1.5 {MPa}.$
We believe that this continuum is produced in a way similar to the VUV continua
of noble gas excimers and that the pressure-dependent shift can be explained by
the interaction of the outer electron of the excimer with the gas.

</DOC>
<DOC>
<DOCNO> 69961 </DOCNO>
The b--> s g g decay in the general two Higgs doublet model


  We study the decay width of the inclusive process b --> s g g in the two
Higgs doublet model with three level flavor changing neutral currents (model
III). We analyse the dependencies of the differential decay width to the s
quark energy E_s and model III parameters, charged Higgs mass m_{H^{\pm}} and
Yukawa coupling \bar{\xi}_{N,bb}^D. We observe that there exist a considerable
enhancement in the decay width for the relevant process. This enhancement can
be reduced by choosing C_7^{eff} as negative and increasing the lower bound of
m_{H^{\pm}} to the large values, such as 800 GeV . This is an interesting
result which gives an idea on the mass m_{H^{\pm}} and sign of C_7^{eff}.

</DOC>
<DOC>
<DOCNO> 72062 </DOCNO>
Flavour-Dependent CP Violation and Natural Suppression of the Electric


  We revisit the supersymmetric CP problem and find that it can be naturally
resolved if the origin of CP violation is closely related to the origin of
flavour structures. In this case, the supersymmetry breaking dynamics do not
bring in any new CP-violating phases. This mechanism requires hermitian Yukawa
matrices which naturally arise in models with a U(3) flavour symmetry. The
neutron electric dipole moment (NEDM) is predicted to be within one-two orders
of magnitude below the current experimental limit. The model also predicts a
strong correlation between A_{CP}(b --> s gamma)and the NEDM. The strong CP
problem is mitigated although not completely solved.

</DOC>
<DOC>
<DOCNO> 71242 </DOCNO>
QCD factorization with heavy quarks


  We further analyze the definition and the calculation of the heavy quark
impact factor at next-to-leading (NL) $\log s$ level, and we provide its
analytical expression in a previously proposed k-factorization scheme. Our
results indicate that k-factorization holds at NL level with a properly chosen
energy scale, and with the same gluonic Green's function previously found in
the massless probe case.

</DOC>
<DOC>
<DOCNO> 170493 </DOCNO>
Time Correlation in Tunneling of Photons


  A thought experiment is considered in which photons are tunneling through an
optical barrier and the moments of their emission and detection are determined
by clocks. The time correlation between the two events is calculated using an
appropriate counting rate formula derived from first principles. A sharp
correlation function is obtained which permits an interpretation in terms of a
tunneling time equal to zero.

</DOC>
<DOC>
<DOCNO> 151379 </DOCNO>
Localization of Matters on a String-like Defect


  After presenting string-like solutions with a warp factor to Einstein's
equations, we study localization of various spin fields on a string-like defect
in a general space-time dimension from the viewpoint of field theory. It is
shown that spin 0 and 2 fields are localized on a defect with the exponentially
decreasing warp factor. Spin 1 field can be also localized on a defect with the
exponentially decreasing warp factor. On the other hand, spin one-half and
three-half fields can be localized on a defect with the exponentially
increasing warp factor, provided that additional interactions are not
introduced. Thus, some mechanism of localization must be invoked for these
fermionic fields. These results are very similar to those of a domain wall in
five space-time dimensions except the case of spin 1 field.

</DOC>
<DOC>
<DOCNO> 100191 </DOCNO>
Witten's Geometric Quantization of the Moduli of CY Threefolds


  In this paper we will use our results about the local deformation theory of
Calabi-Yau manifolds to define a Higgs field on the tangent bundle of the
moduli space of CY threefolds. Combining this Higgs field with the
Levi-Chevitta connection of the Weil-Petersson metrics on the moduli space of
three dimensional CY manifolds, we construct a new $Sp(2h^{2,1}% ,\mathbb{R)}$
connection, following the ideas of Cecotti and Vafa. We prove that this new
connection is a flat connection. We proved earlier that the so-called extended
Teichm\"{u}ller space is a domain of holomorphy. The above described connection
is exactly the flat connection coming from the action of the mapping class
group on the Teichm\"{u}ller space.
  Using this flat connection, we apply the scheme of geometric quantization
introduced by Axelrod, Della Pietra and Witten to the tangent bundle of the
moduli space of three dimensional CY manifolds. By modifying the calculations
of E. Witten done in 1993 to the tangent bundle of the moduli space of CY
threefolds, we derive again the holomorphic anomaly equations of Bershadsky,
Cecotti, Ooguri and Vafa.

</DOC>
<DOC>
<DOCNO> 118612 </DOCNO>
UV Light Curves of Thermonuclear Supernovae


  Ultraviolet light curves are calculated for several thermonuclear supernova
models using a multifrequency radiation hydrodynamic code. It is found that
Chandrasekhar-mass models produce very similar light curves both for detonation
and deflagration. Sub-Chandrasekhar-mass models essentially differ from
``normal'' Chandrasekhar ones regarding behaviour of their UV fluxes.
Differences in absolute brightness and in shape of light curves of
thermonuclear supernovae could be detectable up to 300 Mpc with modern UV space
telescopes.

</DOC>
<DOC>
<DOCNO> 80798 </DOCNO>
Recent results in the center vortex model for the infrared sector of


  A model for the infrared sector of SU(2) Yang-Mills theory, based on magnetic
vortices represented by (closed) random surfaces, is presented. The model
quantitatively describes both confinement and the topological aspects of
Yang-Mills theory. Details (including an adequate list of references) can be
found in hep-lat/9912003 and hep-lat/0004013, both to appear in Nucl. Phys. B.

</DOC>
<DOC>
<DOCNO> 117944 </DOCNO>
HV Ursae Majoris, a new contact binary with early-type components


  We present the first UBV and uvby photometric observations for the short
period variable star HV Ursae Majoris classified as a field RRc variable. The
observed differences between the consecutive minima and the lack of colour
variations disagree with the RRc-classification and suggest the possible binary
nature of HV UMa. In order to reveal the real physical status of this star, we
took medium resolution spectra in the red spectral region centered at 6600 A.
Spectra obtained around the assumed quadratures clearly showed the presence of
the secondary component.
  An improved ephemeris calculated using our and Hipparcos epoch photometry is
Hel. JD_min=2451346.743+/-0.001, P=0.7107523(3) d. A radial velocity curve was
determined by modelling the cores of Halpha profiles with two Gaussian
components. This approximative approach gave a spectroscopic mass ratio of
q_sp=0.19+/-0.03. A modified Lucy model containing a temperature excess of the
secondary was fitted to the V light curve. The obtained set of physical
parameters together with the parallax measurement indicate that this binary
lies far from the galactic plane, and the primary component is an evolved
object, probably a subgiant or giant star. The large temperature excess of the
secondary may suggest a poor thermal contact between the components due to a
relatively recent formation of this contact system.

</DOC>
<DOC>
<DOCNO> 120316 </DOCNO>
Presupernova collapse models with improved weak-interaction rates


  Improved values for stellar weak interaction rates have been recently
calculated based upon a large shell model diagonalization. Using these new
rates (for both beta decay and electron capture), we have examined the
presupernova evolution of massive stars in the range 15-40 Msun. Comparing our
new models with a standard set of presupernova models by Woosley and Weaver, we
find significantly larger values for the electron-to-baryon ratio Ye at the
onset of collapse and iron core masses reduced by approximately 0.1 Msun. The
inclusion of beta-decay accounts for roughly half of the revisions, while the
other half is a consequence of the improved nuclear physics. These changes will
have important consequences for nucleosynthesis and the supernova explosion
mechanism.

</DOC>
<DOC>
<DOCNO> 40087 </DOCNO>
Measurement of the Low-x Behaviour of the Photon Structure Function


  The photon structure function F2-gamma(x,Q**2) has been measured using data
taken by the OPAL detector at centre-of-mass energies of 91Gev, 183Gev and
189Gev, in Q**2 ranges of 1.5 to 30.0 GeV**2 (LEP1), and 7.0 to 30.0 GeV**2
(LEP2), probing lower values of x than ever before. Since previous OPAL
analyses, new Monte Carlo models and new methods, such as multi-variable
unfolding, have been introduced, reducing significantly the model dependent
systematic errors in the measurement.

</DOC>
<DOC>
<DOCNO> 120584 </DOCNO>
Inter-Scale Correlations as Measures of CMB Gaussianity


  A description of CMB temperature fluctuations beyond the power spectrum is
important for verifying models of structure formation, especially in view of
forthcoming high-resolution observations. We argue that higher-order statistics
of inter-scale correlations, because of their low cosmic variance, may be
effective in detecting non-Gaussian features in the CMB. Inter-scale
correlations are generically produced in defect-based models of structure
formation. We analytically study properties of general higher-order cumulants
of Fourier components of homogeneous random fields and design a new set of
statistics suitable for small-scale data analysis. Using simulated non-Gaussian
fields, we investigate the performance of the proposed statistics in presence
of a Gaussian background and pixel noise, using the bispectrum as the
underlying cumulant. Our numerical results suggest that detection of
non-Gaussian features by our method is reliable if the power spectrum of the
non-Gaussian components dominates that of the Gaussian background and noise
within at least a certain range of accessible scales.

</DOC>
<DOC>
<DOCNO> 118019 </DOCNO>
The spark-associated soliton model for pulsar radio emission


  We propose a new, self-consistent theory of coherent pulsar radio emission
based on the non-stationary sparking model of Ruderman & Sutherland (1975),
modified by Gil & Sendyk (2000) in the accompanying Paper I. According to these
authors, the polar cap is populated as densely as possible by a number of
sparks with a characteristic perpendicular dimension D approximately equal to
the polar gap height scale h, separated from each other also by about h. Each
spark reappears in approximately the same place on the polar cap for a time
scale much longer than its life-time and delivers to the open magnetosphere a
sequence of electron-positron clouds which flow orderly along a flux tube of
dipolar magnetic field lines. The overlapping of particles with different
momenta from consecutive clouds leads to effective two-stream instability,
which triggers electrostatic Langmuir waves at the altitudes of about 50
stellar radii. The electrostatic oscillations are modulationally unstable and
their nonlinear evolution results in formation of ``bunch-like'' charged
solitons. A characteristic soliton length along magnetic field lines is about
30 cm, so they are capable of emitting coherent curvature radiation at radio
wavelengths. The net soliton charge is about 10^21 fundamental charges,
contained within a volume of about 10^14 cm^3. For a typical pulsar, there are
about 10^5 solitons associated with each of about 25 sparks operating on the
polar cap at any instant. One soliton moving relativisticaly along dipolar
field lines with a Lorentz factor of the order of 100 generates a power of
about 10^21 erg/s by means of curvature radiation. Then the total power of a
typical radio pulsar can be estimated as being about 10^(27-28) erg/s.

</DOC>
<DOC>
<DOCNO> 13684 </DOCNO>
Correlation versus mean-field contributions to excitons, multi-excitons,


  Single-dot spectroscopy is now able to resolve the energies of excitons,
multi-excitons, and charging of semiconductor quantum dots with ~<1 meV
resolution. We discuss the physical content of these energies and show how they
can be calculated via Quantum Monte Carlo (QMC) and Configuration Interaction
(CI) methods.

</DOC>
<DOC>
<DOCNO> 8823 </DOCNO>
Physical Questions Posed by DNA Condensation


  When multivalent salts are added to dilute DNA solution, the DNA chains
condense into bundles of a well-defined size. We explore two physical problems
motivated by this phenomenon: the origin of the attractive interactions between
the highly-negatively charged DNA chains that cause them to concentrate into
bundles, and the mechanism that provents the bundles from growing indefinitely
large.

</DOC>
<DOC>
<DOCNO> 7992 </DOCNO>
Semiclassical time evolution of the density matrix and tunneling


  The time dependent density matrix of a system with potential barrier is
studied using path integrals. The characterization of the initial state, which
is assumed to be restricted to one side of the barrier, and the time evolution
of the density matrix lead to a three-fold path integral which is evaluated in
the semiclassical limit. The semiclassical trajectories are found to move in
the complex coordinate plane and barrier penetration only arises due to
fluctuations. Both the form of the semiclassical paths and the relevant
fluctuations change significantly as a function of temperature. The
semiclassical analysis leads to a detailed picture of barrier penetration in
the real time domain and the changeover from thermal activation to quantum
tunneling. Deep tunneling is associated with quasi-zero modes in the
fluctuation spectrum about the semiclassical orbits in the long time limit. The
connection between this real time description of tunneling and the standard
imaginary time instanton approach is established. Specific results are given
for a double well potential and an Eckart barrier.

</DOC>
<DOC>
<DOCNO> 84953 </DOCNO>
Solar System Tests of the Equivalence Principle and Constraints on


  In most studies of equivalence principle violation by solar system bodies, it
is assumed that the ratio of gravitational to inertial mass for a given body
deviates from unity by a parameter Delta which is proportional to its
gravitational self-energy. Here we inquire what experimental constraints can be
set on Delta for various solar system objects when this assumption is relaxed.
Extending an analysis originally due to Nordtvedt, we obtain upper limits on
linearly independent combinations of Delta for two or more bodies from Kepler's
third law, the position of Lagrange libration points, and the phenomenon of
orbital polarization. Combining our results, we extract numerical upper bounds
on Delta for the Sun, Moon, Earth and Jupiter, using observational data on
their orbits as well as those of the Trojan asteroids. These are applied as a
test case to the theory of higher-dimensional (Kaluza-Klein) gravity. The
results are three to six orders of magnitude stronger than previous constraints
on the theory, confirming earlier suggestions that extra dimensions play a
negligible role in solar systemdynamics and reinforcing the value of
equivalence principle tests as a probe of nonstandard gravitational theories.

</DOC>
<DOC>
<DOCNO> 152089 </DOCNO>
New instantons in the double-well potential


  A new instanton solution is found in the quantum-mechanical double-well
potential with a four-fermion term. The solution has finite action and depends
on four fermionic collective coordinates. We explain why in general the
instanton action can depend on collective coordinates.

</DOC>
<DOC>
<DOCNO> 119203 </DOCNO>
Signatures of Interstellar-Intracluster Medium Interactions: Spiral


  We investigate the rich cluster Abell 2029 (z~0.08) using optical imaging and
long-slit spectral observations of 52 disk galaxies distributed throughout the
cluster field. No strong emission-line galaxies are present within ~400 kpc of
the cluster center, a region largely dominated by the similarly-shaped X-ray
and low surface brightness optical envelopes centered on the giant cD galaxy.
However, two-thirds of the galaxies observed outside the cluster core exhibit
line emission. H-alpha rotation curves of 14 cluster members are used in
conjunction with a deep I band image to study the environmental dependence of
the Tully-Fisher relation. The Tully-Fisher zero-point of Abell 2029 matches
that of clusters at lower redshifts, although we do observe a relatively larger
scatter about the Tully-Fisher relation. We do not observe any systematic
variation in the data with projected distance to the cluster center: we see no
environmental dependence of Tully-Fisher residuals, R-I color, H-alpha
equivalent width, and the shape and extent of the rotation curves.

</DOC>
<DOC>
<DOCNO> 150929 </DOCNO>
Warped Compactifications and AdS/CFT


  In this talk we discuss two classes of examples of warped products of AdS
spaces in the context of the AdS/CFT correspondence. The first class of
examples appears in the construction of dual Type I' string descriptions to
five dimensional supersymmetric fixed points with E_{N_f+1} global symmetry.
The background is obtained as the near horizon geometry of the D4-D8 brane
system in massive Type IIA supergravity. The second class of examples appears
when considering the N=2 superconformal theories defined on a 3+1 dimensional
hyperplane intersection of two sets of M5 branes. We use the dual string
formulations to deduce properties of these field theories.

</DOC>
<DOC>
<DOCNO> 7896 </DOCNO>
Coexistence of excited states in confined Ising systems


  Using the density-matrix renormalization-group method we study the
two-dimensional Ising model in strip geometry. This renormalization scheme
enables us to consider the system up to the size 300 x infinity and study the
influence of the bulk magnetic field on the system at full range of
temperature. We have found out the crossover in the behavior of the correlation
length on the line of coexistence of the excited states. A detailed study of
scaling of this line is performed. Our numerical results support and specify
previous conclusions by Abraham, Parry, and Upton based on the related bubble
model.

</DOC>
<DOC>
<DOCNO> 119695 </DOCNO>
X-ray and optical follow-up observations of the August 1998 X-ray


  The BeppoSAX Wide Field Cameras detected a transient in NGC6440 on 1998 Aug
22. ROSAT did not detect this source on 1998 Sep 8, indicating that the X-ray
flux had decreased by a factor 400 at least, and/or that the X-ray spectrum had
become appreciably softer. Analysis of archival ROSAT HRI data reveals two
sources associated with NGC6440; one of these may be the transient in
quiescence. We have also obtained B and R images of NGC6440 on 1998 Aug 26 and
again on 1999 July 15, when the transient had returned to quiescence.
Subtraction of these images reveals one object in the core which was brighter
in B, but not in R, during the X-ray outburst. We estimate B=22.7 and (B-R)o<0
on 1998 Aug 26, which makes it a viable candidate counterpart.

</DOC>
<DOC>
<DOCNO> 11010 </DOCNO>
Specific heat of Ce_{0.8}La_{0.2}Al_{3} in magnetic fields: a test of


  The specific heat C of Ce_{0.8}La_{0.2}Al_{3} has been measured as a function
of temperature T in magnetic fields up to 14 T. A large peak in C at 2.3 K has
recently been ascribed to an anisotropic Kondo effect in this compound. A 14-T
field depresses the temperature of the peak by only 0.2 K, but strongly reduces
its height. The corresponding peak in C/T shifts from 2.1 K at zero field to
1.7 K at 14 T. The extrapolated specific heat coefficient C/T(T->0) increases
with field over the range studied. We show that these trends are inconsistent
with the anisotropic Kondo model.

</DOC>
<DOC>
<DOCNO> 83390 </DOCNO>
A Comparison between Supervised Learning Algorithms for Word Sense


  This paper describes a set of comparative experiments, including cross-corpus
evaluation, between five alternative algorithms for supervised Word Sense
Disambiguation (WSD), namely Naive Bayes, Exemplar-based learning, SNoW,
Decision Lists, and Boosting. Two main conclusions can be drawn: 1) The
LazyBoosting algorithm outperforms the other four state-of-the-art algorithms
in terms of accuracy and ability to tune to new domains; 2) The domain
dependence of WSD systems seems very strong and suggests that some kind of
adaptation or tuning is required for cross-corpus application.

</DOC>
<DOC>
<DOCNO> 8883 </DOCNO>
High Temperature Expansion for Frustrated and Unfrustrated S=1/2 Spin


  A computer aided high temperature expansion of the magnetic susceptibility
and the magnetic specific heat is presented and demonstrated for frustrated and
unfrustrated spin chains. The results are analytic in nature since the
calculations are performed in the integer domain. They are provided in the form
of polynomials allowing quick and easy fits. Various representations of the
results are discussed. Combining high temperature expansion coefficients and
dispersion data yields very good agreement already in low order of the
expansion which makes this approach very promising for the application to other
problems, for instance in higher dimensions.

</DOC>
<DOC>
<DOCNO> 72097 </DOCNO>
The Non-commutative Brane World


  We propose a new higher-dimensional mechanism to localize scalar fields as
well as fermionic and gauge fields. The underlying theory is a six-dimensional
non-commutative field theory where non-commutativity is allowed along two extra
infinite spatial dimensions and the four-dimensional brane is provided by a
scalar soliton living in the non-commutative space. Making use of the powerful
correspondence between non-commutative coordinates and operators on a single
particle Hilbert space, we show that the non-commutative brane world admits
localized chiral fermions and it ensures the localization of massless gauge
fields. It may also give rise to a variety of different low-energy spectra
since the localized zero mode may come along either with a discrete tower of
degenerate heavy states or with a tower of Kaluza-Klein heavy states, or it may
even be the only state in the low-energy spectrum.

</DOC>
<DOC>
<DOCNO> 119453 </DOCNO>
Dynamics of the Galactic Bulge using Planetary Nebulae


  Evidence for a bar at the center of the Milky Way triggered a renewed
enthusiasm for dynamical modelling of the Galactic bar-bulge. Our goal is to
compare the kinematics of a sample of tracers, planetary nebulae, widely
distributed over the bulge with the corresponding kinematics for a range of
models of the inner Galaxy. Three of these models are N-body barred systems
arising from the instabilities of a stellar disk (Sellwood, Fux and Kalnajs),
and one is a Schwarzschild system constructed to represent the 3D distribution
of the COBE/DIRBE near-IR light and then evolved as an N-body system for a few
dynamical times (Zhao). For the comparison of our data with the models, we use
a new technique developed by Saha (1998). The procedure finds the parameters of
each model, i.e. the solar galactocentric distance R_o in model units, the
orientation angle phi, the velocity scale (in km/s per model unit), and the
solar tangential velocity which best fit the data.

</DOC>
<DOC>
<DOCNO> 117358 </DOCNO>
Radio emission of the Galactic X-rays binaries with relativistic jets


  Variable non-thermal radio emission from Galactic X-ray binaries is a trace
of relativistic jets, created near accretion disks. The spectral
characteristics of a lot of radio flares in the X-ray binaries with jets (RJXB)
is discussed in this report. We carried out several long daily monitoring
programs with the RATAN-600 radio telescope of the sources: SS433, Cyg X-3,
LSI+61o303, GRS 1915+10 and some others. We also reviewed some data from the
GBI monitoring program at two frequencies and hard X-ray BATSE (20-100 keV) and
soft X-ray RTXE (2-12 keV) ASM data. We confirmed that flaring radio emission
of Cyg X-3 correlated with hard and anti-correlated with soft X-ray emission
during the strong flare (>$ Jy) in May 1997. During two orbital periods we
investigated radio light curves of the remarkable X-binary LSI+61o303. Two
flaring events near a phase 0.6 of the 26.5-day orbital period have been
detected for first time at four frequencies simultaneously. Powerful flaring
events of SS433 were detected at six frequencies in May 1996 and in May 1999.
The decay of the flare is exactly fitted by an exponential law and the rate of
the decay $\tau$ depends upon frequency as tau \propto \nu^{-0.4} in the first
flare and does not depend upon frequency in the second flare, and is equal to
\tau=6+-1 days at frequencies from 0.96 to 21.7 GHz in the last flare in May
1999. Many flaring RJXB show two, exponential and power, laws of flare decay.
Moreover, these different laws could be present in one or several flares and
commonly flare decays are faster at a higher frequency. The decay law seems to
change because of geometric form of the conical hollow jets. The synchrotron
and inverse Compton losses could explain general frequency dependences in flare
evolution. In conclusion we summarized the general radio properties of RJXB.

</DOC>
<DOC>
<DOCNO> 70017 </DOCNO>
Charged radiative pion capture on the nucleon in heavy baryon chiral


  The differential cross sections and s-wave and p-wave multipoles for $\pi^- p
\to \gamma n$ and $\pi^+ n \to \gamma p$ have been calculated through $O(p^3)$
in heavy baryon chiral perturbation theory (HBChPT). Fits to existing data
allow several of the low energy constants to be determined. Generally results
of the calculation compare well with dispersion relation predictions.

</DOC>
<DOC>
<DOCNO> 68172 </DOCNO>
Spin polarisabilities of the nucleon at NLO in the chiral expansion


  We present a calculation of the fourth-order (NLO) contribution to
spin-dependent Compton scattering in heavy-baryon chiral perturbation theory,
and we give results for the four spin polarisabilities. No low-energy
constants, except for the anomalous magnetic moments of the nucleon, enter at
this order. For forward scattering the fourth-order piece of the spin
polarisability of the proton turns out to be almost twice the size of the
leading piece, with the opposite sign. This leads to the conclusion that no
prediction can currently be made for this quantity. For backward scattering the
fourth-order contribution is much smaller than the third-order piece which is
dominated by the anomalous scattering, and so cannot explain the discrepancy
between the CPT result and the current best experimental determination.

</DOC>
<DOC>
<DOCNO> 102137 </DOCNO>
The fourth skein module and the Montesinos-Nakanishi conjecture for


  We study the concept of the fourth skein module of 3-manifolds, that is a
skein module based on the skein relation b_0L_0 + b_1L_1 + b_2L_2 + b_3L_3 = 0
and a framing relation L^{(1)} = aL, where a, b_0, b_3 are invertible. We
introdule the concept of n-algebraic tangles (and links) and analyze the skein
module for 3-algebraic links. As a byproduct we prove the Montesinos-Nakanishi
3-move conjecture for 3-algebraic links (including 3-bridge links).

</DOC>
<DOC>
<DOCNO> 117479 </DOCNO>
The Off State of GX 339-4


  We report BeppoSAX and optical observations of the black hole candidate GX
339-4 during its X-ray `off' state in 1999. The broad-band (0.8-50 keV) X-ray
emission can be fitted by a single power law with spectral index, \alpha ~1.6.
The observed luminosity is 6.6e33 erg s^{-1} in the 0.5-10 keV band, which is
at the higher end of the flux distribution of black hole soft X-ray transients
in quiescence, comparable to that seen in GS 2023+338 and 4U 1630-47. An
optical observation just before the BeppoSAX observation shows the source to be
very faint at these wavelengths as well (B=20.1, V=19.2). By comparing with
previously reported `off' and low states (LS), we conclude that the `off' state
is actually an extension of the LS, i.e. a LS at lower intensities. We propose
that accretion models such as the advection-dominated accretion flows are able
to explain the observed properties in such a state.

</DOC>
<DOC>
<DOCNO> 150385 </DOCNO>
Aharonov-Bohm Effect in Cyclotron and Synchrotron Radiations


  We study the impact of Aharonov-Bohm solenoid on the radiation of a charged
particle moving in a constant uniform magnetic field. With this aim in view,
exact solutions of Klein-Gordon and Dirac equations are found in the
magnetic-solenoid field. Using such solutions, we calculate exactly all the
characteristics of one-photon spontaneous radiation both for spinless and
spinning particle. Considering non-relativistic and relativistic
approximations, we analyze cyclotron and synchrotron radiations in detail.
Radiation peculiarities caused by the presence of the solenoid may be
considered as a manifestation of Aharonov-Bohm effect in the radiation. In
particular, it is shown that new spectral lines appear in the radiation
spectrum. Due to angular distribution peculiarities of the radiation intensity,
these lines can in principle be isolated from basic cyclotron and synchrotron
radiation spectra

</DOC>
<DOC>
<DOCNO> 100341 </DOCNO>
No more than three favourite sites for simple random walk


  We prove that, with probability one, eventually there are no more than three
favourite (i.e. most visited) sites of simple random walk. This partially
answers a relatively long standing question of Pal Erdos and Pal Revesz.

</DOC>
<DOC>
<DOCNO> 120772 </DOCNO>
Structure of Dark Matter Halos From Hierarchical Clustering


  We investigate the structure of the dark matter halo formed in the cold dark
matter scenario using $N$-body simulations. We simulated 12 halos with the mass
of $6.6\times 10^{11}M_{\odot}$ to $8.0\times 10^{14}M_{\odot}$. In almost all
runs, the halos have density cusps proportional to $r^{-1.5}$ developed at the
center, which is consistent with the results of recent high-resolution
calculations. The density structure evolves in a self-similar way, and is
universal in the sense that it is independent of the halo mass and initial
random realization of density fluctuation. The density profile is in good
agreement with the profile proposed by Moore et al. (1999), which has central
slope proportional to $r^{-1.5}$ and outer slope proportional to $r^{-3}$. The
halo grows through repeated accretion of diffuse smaller halos. We argue that
the cusp is understood as a convergence slope for the accretion of tidally
disrupted matter.

</DOC>
<DOC>
<DOCNO> 67886 </DOCNO>
Electroweak Bubble Wall Friction: Analytic Results


  We present an entirely analytic, leading log order determination of the
friction an electroweak bubble wall feels during a first order electroweak
phase transition. The friction is dominated by W bosons, and gives a wall
velocity parametrically ~ alpha_w, and numerically small, ~ .01 -- 0.1
depending on the Higgs mass.

</DOC>
<DOC>
<DOCNO> 70469 </DOCNO>
Neutrinos in Extra Dimensions and the Anomalous Magnetic Moments of


  The use of extra dimensional scenarios as models for neutrino mass affects
many low energy observables. We consider the implications of virtual bulk
neutrinos in precision experiments of the anomalous magnetic moments of the
muon and the electron. We consider neutrino models in factorizable geometry of
the type M_4 x T as well as the sliced AdS_5 non-factorizable geometry. In both
geometries we find finite contributions to g-2 after summing over the KK
excitations of the bulk neutrinos. In the case of Randall-Sundrum geometry, we
find that the muon experiment is approaching the precision necessary to probe
these models.

</DOC>
<DOC>
<DOCNO> 71453 </DOCNO>
Two-photon annihilation into pion pairs


  We discuss pion pair production in two-photon collisions in two different
kinematical regimes. When both photons are real and at moderately large
center-of-mass energy s we elaborate on partonic transverse momentum and
Sudakov corrections within the hard scattering approach. We also point out the
difference between our approach and that of other authors. When one of the
photons is highly virtual the produced pion pair can be described in terms of a
two-pion distribution amplitude, for which we derive the perturbative limit at
large s.

</DOC>
<DOC>
<DOCNO> 102542 </DOCNO>
Exterior algebra methods for the Minimal Resolution Conjecture


  If r\geq 6, r\neq 9, we show that the Minimal Resolution Conjecture fails for
a general set of m points in P^r for almost 1/2\sqrt r values of m. This
strengthens the result of Eisenbud and Popescu [1999], who found a unique such
m for each r in the given range. Our proof begins like a variation of that of
Eisenbud and Popescu, but uses exterior algebra methods as explained by
Eisenbud and Schreyer [2000] to avoid the degeneration arguments that were the
most difficult part of the Eisenbud-Popescu proof. Analogous techniques show
that the Minimal Resolution Conjecture fails for linearly normal curves of
degree d and genus g when d\geq 3g-2, g\geq 4, reproving results of Schreyer,
Green, and Lazarsfeld.

</DOC>
<DOC>
<DOCNO> 150389 </DOCNO>
Fermion in the Nonabelian Gauge Field Theory in 2+1 Dimensions


  The massive SU(2) gauge field theory coupled with fermions is considered in
2+1 dimensions. Quark energy spectrum and radiative shift in constant external
nonabelian field, being exact solution of the gauge field equations with the
Chern-Simons term, are calculated. Under the condition $m = \theta/4$ the quark
state is shown to be supersymmetric.

</DOC>
<DOC>
<DOCNO> 40032 </DOCNO>
Heavy flavour physics results from LEP1


  Recent heavy flavour results from the LEP experiments are presented. These
include a search for new physics in rare B decays, a new model-independent
measurement of the b-quark fragmentation function at the Z peak, updated
measurements of |Vcb|, results on DeltaGamma_s, searches for B0s oscillations,
as well as a new measurement of sin(2beta). Many combined results, obtained by
dedicated working groups are also given...

</DOC>
<DOC>
<DOCNO> 102198 </DOCNO>
Monomialization of Morphisms From 3 Folds to Surfaces


  Suppose that $\Phi:X\to Y$ is a morphism from a 3 fold to a surface (over an
algebraically closed field of characteristic zero). We prove that there exist
sequences of blowups of nonsingular subvarieties $X_1\to X$ and $Y_1\to Y$ such
that the morphism $\Phi_1:X_1\to Y_1$ is a ``Monomial Morphism''. As a
corollary, we show that we can make $\Phi_1$ a toroidal morphism.

</DOC>
<DOC>
<DOCNO> 102829 </DOCNO>
Type A fusion rules from elementary group theory


  We show how the fusion rules for an affine Kac-Moody Lie algebra g of type
A_{n-1}, n = 2 or 3, for all positive integral level k, can be obtained from
elementary group theory. The orbits of the kth symmetric group, S_k, acting on
k-tuples of integers modulo n, Z_n^k, are in one-to-one correspondence with a
basis of the level k fusion algebra for g. If [a],[b],[c] are any three orbits,
then S_k acts on T([a],[b],[c]) = {(x,y,z)\in [a]x[b]x[c] such that x+y+z=0},
which decomposes into a finite number, M([a],[b],[c]), of orbits under that
action. Let N = N([a],[b],[c]) denote the fusion coefficient associated with
that triple of elements of the fusion algebra. For n = 2 we prove that
M([a],[b],[c]) = N, and for n = 3 we prove that M([a],[b],[c]) = N(N+1)/2. This
extends previous work on the fusion rules of the Virasoro minimal models
[Akman, Feingold, Weiner, Minimal model fusion rules from 2-groups, Letters in
Math. Phys. 40 (1997), 159-169].

</DOC>
<DOC>
<DOCNO> 71992 </DOCNO>
Final state interaction in inclusive and exclusive quasi-elastic


  We discuss a new approach to final state interactions, that keeps explicitly
into account the virtuality of the ejected nucleon in quasi-elastic $A(e,e'p)X$
scattering at very large $Q^2$, and we present some recent results, at
moderately large $Q^2$ values, for the nuclear transparency in $^4He$, $^{16}O$
and $^{40}Ca$ and for the momentum distributions of $^4He$.

</DOC>
<DOC>
<DOCNO> 85355 </DOCNO>
LISA Sources in Globular Clusters


  Globular clusters house a population of compact binaries that will be
interesting gravitational wave sources for LISA. We provide estimates for the
numbers of sources of several categories and discuss the sensitivity of LISA to
detecting these sources. The estimated total number of detectable sources
ranges from about 10 to about 1000 with gravitational wave frequencies above 1
mHz. These sources are typically undetectable by any other means and thus offer
an opportunity for doing true gravitational-wave astronomy. The detection of
these sources would provide information about both binary star evolution and
the dynamics of globular clusters.

</DOC>
<DOC>
<DOCNO> 71500 </DOCNO>
Reconstructing Supersymmetric Theories at the Linear Collider


  High precision measurements at the linear collider will allow a model-
independent reconstruction of nature at high energy scales. The method of
bottom-up extrapolation from the electroweak scale to the GUT scale is
explained and both a universal minimal supergravity and a gaugino-mediated
model are presented as examples. Comparisons are made with the LHC-only case.

</DOC>
<DOC>
<DOCNO> 169936 </DOCNO>
Teleportation Scheme of S-level Quantum Pure States by Two-level EPRs


  Unknown quantum pure states of arbitrary but definite S-level of a particle
can be transferred onto a group of remote two-level particles through two-level
EPRs as many as the number of those particles in this group. We construct such
a kind of teleportation, the realization of which need a nonlocal unitary
transformation to the quantum system that is made up of the s-level particle
and all the two-level particles at one end of the EPRs, and measurements to all
the single particles in this system. The unitary transformation to more than
two particles is also written into the product form of two-body unitary
transformations.

</DOC>
<DOC>
<DOCNO> 69337 </DOCNO>
Analytical Heavy Quark Expansion in the 't Hooft Model


  We present a number of exact relations for the heavy quark limit and develop
an analytical 1/m_Q expansion for heavy mesons in the 't Hooft model. Among the
new results are relation 3\mu_\pi^2=\bar\Lambda^2 - m_{sp}^2+\beta^2, 1/m_Q
corrections to the decay constants, to the kinetic expectation values and
1/m_Q^2 nonperturbative corrections to the B->D amplitude at zero recoil. The
properties of the IW functions are addressed and the small velocity sum rules
are verified.

</DOC>
<DOC>
<DOCNO> 99693 </DOCNO>
A flexible error estimate for the application of centre manifold theory


  In applications of centre manifold theory we need more flexible error
estimates than that provided by, for example, the Approximation Theorem~3 by
Carr (1981,1983). Here we extend the theory to cover the case where the order
of approximation in parameters and that in dynamical variables may be
completely different. This allows, for example, the effective evaluation of
low-dimensional dynamical models at finite parameter values.

</DOC>
<DOC>
<DOCNO> 69471 </DOCNO>
Superheavy Particles in Friedmann Cosmology and the Dark Matter Problem


  The model of creation of observable particles and particles of the dark
matter, considered to be superheavy particles, due to particle creation by the
gravitational field of the Friedmann model of the early Universe is given.
Estimates on the parameters of the model leading to observable values of the
baryon number of the Universe and the dark matter density are made.

</DOC>
<DOC>
<DOCNO> 10986 </DOCNO>
Many-body theory of pump-probe spectra for highly excited semiconductors


  We present a unified theory for pump-probe spectra in highly excited
semiconductors, which is applicable throughout the whole density regime
including the high-density electron-hole BCS state and the low-density
excitonic Bose-Einstein condensate (BEC). The analysis is based on the BCS-like
pairing theory combined with the Bethe-Salpeter (BS) equation, which first
enables us to incorporate the state-filling effect, the band-gap
renormalization and the strong/weak electron-hole pair correlations in a
unified manner. We show that the electron-hole BCS state is distinctly
stabilized by the intense pump-light, and this result strongly suggests that
the macroscopic quantum state can be observed under the strong photoexcitation.
The calculated spectra considerably deviate from results given by the BCS-like
mean field theory and the simple BS equation without electron-hole pair
correlation especially in the intermediate density states between the
electron-hole BCS state and the excitonic BEC state. In particular, we find the
sharp stimulated emission and absorption lines which originate from the optical
transition accompanied by the collective phase fluctuation mode in the
electron-hole BCS state. From the pump-probe spectral viewpoint, we show that
this fluctuation mode changes to the exciton mode with decreasing carrier
density

</DOC>
<DOC>
<DOCNO> 7712 </DOCNO>
Non-Linear and Non-Local Meissner Effect in Superconducting Wires


  The structure of the Meissner effect in a current-carrying cylindrical wire
with arbitrary disorder is studied using a numerical procedure that is exact
within the semiclassical approximation. A distribution of currents is found
that is non-monotonous as a function of the radial coordinate. For high
currents, a robust gapless superconducting state develops at the surface of
both clean and dirty leads. Our calculation provides a quantitative theory of
the critical current in realistic wires.

</DOC>
<DOC>
<DOCNO> 123141 </DOCNO>
New Evidence for the Unified Scheme of BL Lac Objects and Fri Radio


  In this paper, we collect radio and X-ray observations for most
Fanaroff-Riley I (FRI) radio galaxies in the Zirbel-Baum radio galaxy sample,
and investigate the distribution of the radio-to-X-ray effective spectral
index, $\alpha_{rx}$, to test the unified scheme of BL Lac objects and FRI
radio galaxies. It is found that the range of $\alpha_{rx}$ for FRI radio
galaxies is almost the same as that for BL Lac objects, that the distribution
of $\alpha_{rx}$ probably peaks at the same position as BL Lac objects, and
that the distribution of $\alpha_{rx}$ for FRIs is similar to that for BL Lac
objects. These suggest that there exist two subclasses of FRI radio galaxies:
one is HBL-like, and the other is LBL-like, corresponding to high-energy-peaked
(HBL) and low--energy-peaked (LBL) BL Lac objects, respectively. This result is
consistent with previous VLA observations, and supports the unified scheme of
BL Lac objects and FRI radio galaxies.

</DOC>
<DOC>
<DOCNO> 13283 </DOCNO>
Analog gravity from Bose-Einstein condensates


  We analyze prospects for the use of Bose-Einstein condensates as
condensed-matter systems suitable for generating a generic ``effective
metric'', and for mimicking kinematic aspects of general relativity. We extend
the analysis due to Garay et al, [gr-qc/0002015, gr-qc/0005131]. Taking a long
term view, we ask what the ultimate limits of such a system might be. To this
end, we consider a very general version of the nonlinear Schrodinger equation
(with a 3-tensor position-dependent mass and arbitrary nonlinearity). Such
equations can be used for example in discussing Bose-Einstein condensates in
heterogeneous and highly nonlinear systems. We demonstrate that at low momenta
linearized excitations of the phase of the condensate wavefunction obey a
(3+1)-dimensional d'Alembertian equation coupling to a (3+1)-dimensional
Lorentzian-signature ``effective metric'' that is generic, and depends
algebraically on the background field. Thus at low momenta this system serves
as an analog for the curved spacetime of general relativity. In contrast at
high momenta we demonstrate how to use the eikonal approximation to extract a
well-controlled Bogoliubov-like dispersion relation, and (perhaps unexpectedly)
recover non-relativistic Newtonian physics at high momenta. Bose-Einstein
condensates appear to be an extremely promising analog system for probing
kinematic aspects of general relativity.

</DOC>
<DOC>
<DOCNO> 69413 </DOCNO>
Lorentz and CPT Tests in Atomic Systems


  A review of Lorentz and CPT tests performed in atomic systems is presented. A
theoretical framework extending QED in the context of the standard model is
used to analyze a variety of systems. Experimental signatures of possible
Lorentz and CPT violation in these systems are investigated. Estimated bounds
attainable in future experiments and actual bounds obtained in recent
experiments are given.

</DOC>
<DOC>
<DOCNO> 70784 </DOCNO>
Color conductivity and ladder summation in hot QCD


  The color conductivity is computed at leading logarithmic order using a Kubo
formula. We show how to sum an infinite series of planar ladder diagrams,
assuming some approximations based on the dominance of soft scattering
processes between hard particles in the plasma. The result agrees with the one
obtained previously from a kinetical approach.

</DOC>
<DOC>
<DOCNO> 118960 </DOCNO>
Multiple Cyclotron Lines in the Spectrum of 4U 0115+63


  We report phase resolved spectroscopy of the transient accreting pulsar,
4U0115+63. For the first time, more than two cylotron resonance scattering
features are detected in the spectrum of an X-ray pulsar. The shape of the
fundamental line appears to be complex, and this is in agreement with
predictions of Monte-Carlo models. As in other pulsars, the line energies and
optical depths are strong functions of pulse phase. One possible model for this
is an offset of the dipole of the neutron star magnetic field.

</DOC>
<DOC>
<DOCNO> 123254 </DOCNO>
The parsec-scale central components of FR I radio galaxies


  A majority of a complete sample of 3CR FR I radio galaxies show unresolved
optical nuclear sources on the scales of 0.1 arcsec. About half of the 3CR FR
II radio galaxies observed with the HST also show Compact Central Cores (CCC).
These CCCs have been interpreted as the optical counterparts of the non-thermal
radio cores in these radio galaxies (Chiaberge, Capetti, & Celotti 1999). We
show that the optical flux density of the CCCs in FR Is is correlated with the
radio core prominence. This correlation supports the argument of Chiaberge et
al. that the CCC radiation is of a non-thermal synchrotron origin, which is
relativistically beamed along with the radio emission.

</DOC>
<DOC>
<DOCNO> 121696 </DOCNO>
The Wisconsin H-Alpha Mapper Northern Sky Survey


  The Wisconsin H-Alpha Mapper (WHAM) has completed a survey in Balmer Alpha of
the entire Northern sky above declination -30 deg. This survey provides the
first calibrated, velocity-resolved map of the H-Alpha emission from the
Galaxy. With one-degree spatial resolution, 12 km s^{-1} velocity resolution,
and sensitivity to features as faint as 0.1 R (EM ~ 0.2 cm^{-6} pc), this
survey provides the deepest maps of the ionized content of the Galaxy to date.
In addition to probing the detailed kinematic structure of the Warm Ionized
Medium and the vertical structure of the ionized content in spiral arms,
initial results include the discovery of several faint, extended (d > 1\deg) H
II regions and the first map of the ionized component of an intermediate
velocity cloud.

</DOC>
<DOC>
<DOCNO> 12904 </DOCNO>
Theory of the Reentrant Charge-Order Transition in the Manganites


  A theoretical model for the reentrant charge-order transition in the
manganites is examined. This transition is studied with a purely electronic
model for the Mn electrons: the extended Hubbard model. The electron-phonon
coupling results in a large nearest-neighbor repulsion between electrons. Using
a finite-temperature Lanczos technique, the model is diagonalized on a 16-site
periodic cluster to calculate the temperature-dependent phase boundary between
the charge-ordered and homogeneous phases. A reentrant transition is found. The
results are discussed with respect to the specific topology of the 16-site
cluster.

</DOC>
<DOC>
<DOCNO> 152378 </DOCNO>
Conformal Non-Geometric Gravity in Six Dimensions and M-Theory above the


  The proposal that a strong coupling limit of the five-dimensional type II
string theory (M-theory compactified on a 6-torus) in which the Planck length
becomes infinite could give a six-dimensional superconformal phase of M-theory
is reviewed. This limit exists for the free theory, giving a 6-dimensional
theory with (4,0) supersymmetry compactified on a circle whose radius gives the
5-dimensional Planck length. The free 6-dimensional theory has a fourth rank
tensor gauge field with the symmetries of the Riemann tensor instead of a
symmetric tensor gauge field, but its dimensional reduction gives conventional
linearised gravity in five dimensions. The possibility of an interacting form
of this theory existing and the consequences it would have for the geometric
picture of gravity are discussed.

</DOC>
<DOC>
<DOCNO> 68530 </DOCNO>
Parametric Amplification of Metric Fluctuations During Reheating in Two


  We study the parametric amplification of super-Hubble-scale scalar metric
fluctuations at the end of inflation in some specific two-field models of
inflation, a class of which is motivated by hybrid inflation. We demonstrate
that there can indeed be a large growth of fluctuations due to parametric
resonance and that this effect is not taken into account by the conventional
theory of isocurvature perturbations. Scalar field interactions play a crucial
role in this analysis. We discuss the conditions under which there can be
nontrivial parametric resonance effects on large scales.

</DOC>
<DOC>
<DOCNO> 85630 </DOCNO>
Global monopoles and scalar fields as the electrogravity dual of


  We prove that both global monopole and minimally coupled static zero mass
scalar field are electrogravity dual of the Schwarzschild solution or flat
space and they share the same equation of state, $T^0_0 - T^i_i = 0$. This
property was however known for the global monopole spacetime while it is for
the first time being established for the scalar field. In particular, it turns
out that the Xanthopoulos - Zannias scalar field solution is dual to flat
space.

</DOC>
<DOC>
<DOCNO> 11632 </DOCNO>
Scattering Theory of Kondo Mirages and Observation of Single Kondo Atom


  We explain the origin of the Kondo mirage seen in recent quantum corral
Scanning Tunneling Microscope (STM) experiments with a scattering theory of
electrons on the surfaces of metals. Our theory combined with experimental data
provides the first direct observation of a single Kondo atom phase shift. The
Kondo mirage at the empty focus of an elliptical quantum corral is shown to
arise from multiple electron bounces off the walls of the corral in a manner
analagous to the formation of a real image in optics. We demonstrate our theory
with direct quantitive comparision to experimental data.

</DOC>
<DOC>
<DOCNO> 99543 </DOCNO>
On the cover time of planar graphs


  The cover time of a finite connected graph is the expected number of steps
needed for a simple random walk on the graph to visit all the vertices. It is
known that the cover time on any n-vertex, connected graph is at least (1+o(1))
n log(n) and at most (1+o(1))(4/27)n^3. This paper proves that for
bounded-degree planar graphs the cover time is at least c n(log n)^2, and at
most 6n^2, where c is a positive constant depending only on the maximal degree
of the graph. The lower bound is established via use of circle packings.

</DOC>
<DOC>
<DOCNO> 169617 </DOCNO>
Quantum secret sharing for general access structures


  We explore the conversion of classical secret-sharing schemes to quantum
ones, and how this can be used to give efficient QSS schemes for general
adversary structures. Our first result is that quantum secret-sharing is
possible for any structure for which no two disjoint sets can reconstruct the
secret (this was also proved, somewhat differently, by D. Gottesman). To obtain
this we show that a large class of linear classical SS schemes can be converted
into quantum schemes of the same efficiency.
  We also give a necessary and sufficient condiion for the direct conversion of
classical schemes into quantum ones, and show that all group homomorphic
schemes satisfy it.

</DOC>
<DOC>
<DOCNO> 84676 </DOCNO>
Spin 1/2 Field Theory in the de Sitter space-time


  A covariant quantization of the free spinor fields (s=1/2) in 4-dimensional
de Sitter (dS) space-time based on analyticity in the complexified
pseudo-Riemanian manifold is presented. We define the Wigthman two-point
function ${\cal W}(x,y)$, which satisfies the conditions of: a) positivity, b)
locality, c) covariance, and d) normal analyticity. Then the Hilbert space
structure and the field operators $\psi (f)$ are defined. A
coordinate-independent formula for the unsmeared field operator $\psi (x)$ is
also given.

</DOC>
<DOC>
<DOCNO> 102728 </DOCNO>
One-sided M-Ideals and Multipliers in Operator Spaces, I


  The theory of M-ideals and multiplier mappings of Banach spaces naturally
generalizes to left (or right) M-ideals and multiplier mappings of operator
spaces. These subspaces and mappings are intrinsically characterized in terms
of the matrix norms. In turn this is used to prove that the algebra of left
adjointable mappings of a dual operator space X is a von Neumann algebra. If in
addition X is an operator A--B-bimodule for $C^{*}$-algebras A and B, then the
module operations on X are automatically weak$^{*}$ continuous. One sided
L-projections are introduced, and analogues of various results from the
classical theory are proved. An assortment of examples is considered.

</DOC>
<DOC>
<DOCNO> 102696 </DOCNO>
On harmonic elements for semi-simple Lie algebra


  Let ${\goth g}$ be a semi-simple complex Lie algebra, ${\goth g}={\goth
n^-}\oplus{\goth h}\oplus{\goth n}$ its triangular decomposition. Let $U({\goth
g})$, resp. $U_q({\goth g})$, be its enveloping algebra, resp. its quantized
enveloping algebra.
  This article gives a quantum approach to the combinatorics of (classical)
harmonic elements and Kostant's generalized exponents for ${\goth \g}$. On the
one hand, we give specialization results concerning harmonic elements, central
elements of $U_q({\goth g})$, and the Joseph and Letzter's decomposition. For
${\goth g}={\goth sl}_{n+1}$, we describe the specialization of quantum
harmonic space in the ${\math N}$-filtered algebra $U({\goth sl}_{n+1})$ as the
materialization of a theorem of Lascoux-Leclerc-Thibon. This enables us to
study a Joseph-Letzter decomposition in the algebra $U({\goth sl}_{n+1})$. On
the other hand, we prove that highest weight harmonic elements can be
calculated in terms of the dual of Lusztig's canonical base. In the simply
laced case, we parametrize a base of $\n$-invariants of minimal primitive
quotients by the set $\co$ of integral points of a convex cone.

</DOC>
<DOC>
<DOCNO> 11937 </DOCNO>
Conserved Dynamics and Interface Roughening in Spontaneous Imbibition :


  The propagation and roughening of a fluid-gas interface through a disordered
medium in the case of capillary driven spontaneous imbibition is considered.
The system is described by a conserved (model B) phase-field model, with the
structure of the disordered medium appearing as a quenched random field
$\alpha({\bf x})$. The flow of liquid into the medium is obtained by imposing a
non-equilibrium boundary condition on the chemical potential, which reproduces
Washburn's equation $H \sim t^{1/2}$ for the slowing down motion of the average
interface position $H$. The interface is found to be superrough, with global
roughness exponent $\chi \approx 1.25$, indicating anomalous scaling. The
spatial extent of the roughness is determined by a length scale $\xi_{\times}
\sim H^{1/2}$ arising from the conservation law. The interface advances by
avalanche motion, which causes temporal multiscaling and qualitatively
reproduces the experimental results of Horv\a'ath and Stanley [Phys. Rev. E
{\bf 52} 5166 (1995)] on the temporal scaling of the interface.

</DOC>
<DOC>
<DOCNO> 40334 </DOCNO>
Tagging Two-Photon Production at the LHC


  Tagging two-photon production offers a significant extension of the LHC
physics programme. Effective luminosity of high-energy gamma-gamma collisions
reaches 1% of the proton-proton luminosity and the standard detector techniques
used for measuring very forward proton scattering should allow for a reliable
extraction of interesting two-photon interactions. Particularly exciting is a
possibility of detecting two-photon exclusive Higgs boson production at the
LHC.

</DOC>
<DOC>
<DOCNO> 72114 </DOCNO>
A Feynman Diagram Analyser DIANA - Graphic Facilities


  New developments concerning the extension of the recently introduced Feynman
diagram analyser DIANA are presented.

</DOC>
<DOC>
<DOCNO> 119020 </DOCNO>
ISO Spectroscopy of the Young Bipolar Nebulae S106 IR and Cep A East


  We present the results of ISO SWS and LWS grating scans towards the embedded
Young Stellar Objects (YSOs) S106 IR and Cep A East. Emission from the pure
rotational lines of H2 and the infrared fine structure lines of [C II], [O I],
[S I], [Si II] and [Fe II], as well as absorption bands due to H2O, CO and CO2
ice were detected toward Cep A. In S106 we detected emission lines of H2, CO, H
I, and a large number of ionized species including Fe, O, N, C, Si, S, Ne and
Ar. S106 also shows many of the infrared PAH bands in emission. Excitation
temperatures and molecular hydrogen masses were derived from the low-lying pure
rotational levels of H2 and are 500 and 730 K and 8 and 3 x 10^{-3} solar
masses for S106 and Cep A, respectively. Since both objects are expected to
have several solar masses of H2 in their environment, we conclude that in both
cases the bulk of the H2 is cooler than a few hundred Kelvins. Excitation
temperatures and line ratios were compared with those predicted by theoretical
models for PDRs and dissociative and non-dissociative shocks. The [S I] 25.2
micron/[Si II] 34.8 micron ratio is a particularly useful shock versus PDR
discriminant and we conclude that S106 IR is dominated by PDR emission while
Cep A East has a large shock component. From an analysis of the ionic lines in
S106 we conclude that the central star must have a temperature around 37,000 K,
corresponding to a spectral type of O8. From its luminosity it is concluded
that the driving source of Cep A must also be a massive early-type star. The
absence of strong high-ionization ionic lines in its ISO spectrum shows that
Cep A has not yet created a significant H II region and must be younger than
S106, illustrating the process of the clearing of the surroundings of a massive
young star.

</DOC>
<DOC>
<DOCNO> 85109 </DOCNO>
Quantum Fluctuations of Bulk Inflaton in Inflationary Brane World


  The inflationary scenario for the brane world driven by the bulk inflaton is
proposed. The quantum fluctuations of the inflaton is calculated and compared
to those of the conventional 4-dimensional inflationary scenario. It is shown
that the deviation of the primordial spectrum of this model from that of the
conventional one is too small to be observed even if $AdS$ radius is very
large. Hence, it turns out that the inflation caused by the bulk inflaton is
viable in the context of brane world cosmology.

</DOC>
<DOC>
<DOCNO> 7661 </DOCNO>
Holons on a meandering stripe: quantum numbers


  We attempt to access the regime of strong coupling between charge carriers
and transverse dynamics of an isolated conducting ``stripe'', such as those
found in cuprate superconductors. A stripe is modeled as a partially doped
domain wall in an antiferromagnet (AF), introduced in the context of two
different models: the t-J model with strong Ising anisotropy, and the Hubbard
model in the Hartree-Fock approximation. The domain walls with a given linear
charge density are supported artificially by boundary conditions. In both
models we find a regime of parameters where doped holes lose their spin and
become holons (charge Q=1, spin S_z=0), which can move along the stripe without
frustrating AF environment. One aspect in which the holons on the AF domain
wall differ from those in an ordinary one-dimensional electron gas is their
transverse degree of freedom: a mobile holon always resides on a transverse
kink (or antikink) of the domain wall. This gives rise to two holon flavors and
to a strong coupling between doped charges and transverse fluctuations of a
stripe.

</DOC>
<DOC>
<DOCNO> 81010 </DOCNO>
Lattice supersymmetry with domain wall fermions


  Supersymmetry, like Poincare symmetry, is softly broken at finite lattice
spacing provided the gaugino mass term is strongly suppressed. Domain wall
fermions provide the mechanism for suppressing this term by approximately
imposing chiral symmetry. We present the first numerical simulations of N=1
supersymmetric SU(2) Yang-Mills on the lattice in four dimensions using domain
wall fermions.

</DOC>
<DOC>
<DOCNO> 100184 </DOCNO>
The asymptotic behavior of the colored Jones function of a knot and its


  I show various calculations of the limit of the colored Jones function for
the figure-eight knot and confirm R. Kashaev's conjecture in this case.

</DOC>
<DOC>
<DOCNO> 70349 </DOCNO>
Two Loop QCD Vertices and Three Loop MOM $\beta$ functions


  We present numerical results for the two loop QCD corrections to the ghost
gluon vertex, the quark gluon vertex, and the triple gluon vertex in the
massless limit at the symmetric point. We restrict ourselves to the tensor
structures existing in the tree level. The corrections are used to examine
different coupling constant definitions in momentum subtraction schemes and the
corresponding three-loop $\beta$ functions.

</DOC>
<DOC>
<DOCNO> 150583 </DOCNO>
Noncommutative Gauge Theories from Deformation Quantization


  We construct noncommutative gauge theories based on the notion of the Weyl
bundle, which appears in Fedosov's construction of deformation quantization on
an arbitrary symplectic manifold. These correspond to D-brane worldvolume
theories in non-constant B-field and curved backgrounds in string theory. All
such theories are embedded into a "universal" gauge theory of the Weyl bundle.
This shows that the combination of a background field and a noncommutative
field strength has universal meaning as a field strength of the Weyl bundle. We
also show that the gauge equivalence relation is a part of such a "universal"
gauge symmetry.

</DOC>
<DOC>
<DOCNO> 152475 </DOCNO>
Ricci-flat Metrics, Harmonic Forms and Brane Resolutions


  We discuss the geometry and topology of the complete, non-compact, Ricci-flat
Stenzel metric, on the tangent bundle of S^{n+1}. We obtain explicit results
for all the metrics, and show how they can be obtained from first-order
equations derivable from a superpotential. We then provide an explicit
construction for the harmonic self-dual (p,q)-forms in the middle dimension
p+q=(n+1) for the Stenzel metrics in 2(n+1) dimensions. Only the (p,p)-forms
are L^2-normalisable, while for (p,q)-forms the degree of divergence grows with
|p-q|. We also construct a set of Ricci-flat metrics whose level surfaces are
U(1) bundles over a product of N Einstein-Kahler manifolds, and we construct
examples of harmonic forms there. As an application, we construct new examples
of deformed supersymmetric non-singular M2-branes with such 8-dimensional
transverse Ricci-flat spaces. We show explicitly that the fractional D3-branes
on the 6-dimensional Stenzel metric found by Klebanov and Strassler is
supported by a pure (2,1)-form, and thus it is supersymmetric, while the
example of Pando Zayas-Tseytlin is supported by a mixture of (1,2) and (2,1)
forms. We comment on the implications for the corresponding dual field theories
of our resolved brane solutions.

</DOC>
<DOC>
<DOCNO> 119991 </DOCNO>
The Amplitude of the Kilohertz Quasi-periodic Oscillations in 4U


  We study the kilohertz quasi-periodic oscillations (kHz QPOs) in the low-mass
X-ray binaries 4U 1728-34, 4U 1608-52, and Aql X-1. Each source traces out a
set of nearly parallel lines in a frequency vs. X-ray count rate diagram. We
find that between two of these tracks, for similar QPO frequency, the source
count rate can differ by up to a factor of ~ 4, whereas at the same time the
rms amplitude of the kHz QPOs is only a factor of ~ 1.1 different. We also find
that, for 4U 1608-52 and Aql X-1, the rms spectrum of the kHz QPOs does not
depend upon which track the source occupies in the frequency vs. X-ray count
rate diagram. Our results for 4U 1728-34, 4U 1608-52, and Aql X-1 are
inconsistent with scenarios in which the properties of the kHz QPOs are only
determined by the mass accretion rate through the disk, whereas X-ray count
rate also depends upon other sources of energy that do not affect the QPOs.

</DOC>
<DOC>
<DOCNO> 84482 </DOCNO>
Cosmic magnetism, curvature and the expansion dynamics


  We discuss how a cosmological magnetic field could affect the expansion of
the universe, through its interaction with the spacetime geometry. The tension
of the field lines means that the magneto-curvature coupling tends to
accelerate positively curved regions and decelerate those with negative
curvature. Depending on the equation of state of the matter, the effect varies
from mimicking that of a cosmological constant to resembling a time-decaying
quintessence. Most interestingly, the coupling between magnetism and geometry
implies that even weak fields have a significant impact if the curvature
contribution is strong. This leads to kinematical complications that can
inhibit the onset of the accelerated phase in spatially open inflationary
models. We employ a simple cosmological model to illustrate these effects and
examine the conditions necessary for them to have a appreciable impact.

</DOC>
<DOC>
<DOCNO> 121213 </DOCNO>
The Chemical Evolution of the Universe I: High Column Density Absorbers


  We construct a simple, robust model of the chemical evolution of galaxies
from high to low redshift, and apply it to published observations of damped
Lyman-alpha quasar absorption line systems (DLAs). The elementary model assumes
quiescent star formation and isolated galaxies (no interactions, mergers or gas
flows). We consider the influence of dust and chemical gradients in the
galaxies, and hence explore the selection effects in quasar surveys. We fit
individual DLA systems to predict some observable properties of the absorbing
galaxies, and also indicate the expected redshift behaviour of chemical element
ratios involving nucleosynthetic time delays.
  Despite its simplicity, our `monolithic collapse' model gives a good account
of the distribution and evolution of the metallicity and column density of
DLAs, and of the evolution of the global star formation rate and gas density
below redshifts z 3. However, from the comparison of DLA observations with our
model, it is clear that star formation rates at higher redshifts (z>3) are
enhanced. Galaxy interactions and mergers, and gas flows very probably play a
major role.

</DOC>
<DOC>
<DOCNO> 68300 </DOCNO>
Implications of Anomalous U(1) Symmetry in Unified Models: the Flipped


  A generic feature of string-derived models is the appearance of an anomalous
Abelian U(1)_A symmetry which, among other properties, constrains the Yukawa
couplings and distinguishes the three families from each other. In this paper,
we discuss in a model-independent way the general constraints imposed by such a
U(1)_A symmetry on fermion masses, R-violating couplings and proton-decay
operators in a generic flipped SU(5) x U(1)' model. We construct all possible
viable fermion mass textures and give various examples of effective low-energy
models which are distinguished from each other by their different predictions
for B-, L- and R-violating effects. We pay particular attention to predictions
for neutrino masses, in the light of the recent Super-Kamiokande data.

</DOC>
<DOC>
<DOCNO> 123090 </DOCNO>
In-Orbit Performance of the Space Telescope NINA and GCR Flux


  The NINA apparatus, on board the Russian satellite Resurs-01 n.4, has been in
polar orbit since 1998 July 10, at an altitude of 840 km. Its main scientific
task is to study the galactic, solar and anomalous components of cosmic rays in
the energy interval 10--200 MeV/n. In this paper we present a description of
the instrument and its basic operating modes. Measurements of Galactic Cosmic
Ray spectra will also be shown.

</DOC>
<DOC>
<DOCNO> 102592 </DOCNO>
Orthonormal integrators based on Householder and Givens transformations


  We carry further our work [DV2] on orthonormal integrators based on
Householder and Givens transformations. We propose new algorithms and pay
particular attention to appropriate implementation of these techniques. We also
present a suite of Fortran codes and provide numerical testing to show the
efficiency and accuracy of our techniques.

</DOC>
<DOC>
<DOCNO> 150793 </DOCNO>
M-Theory N=1 Effective Supergravity in Four Dimensions


  We present a general `off-shell' description of the effective N=1
supergravity describing the low-energy limit of M-theory compactified on
(Calabi-Yau) x S1/Z2. In our formulation, the M-theory Bianchi identities are
imposed by the equations of motion of four-dimensional supermultiplets.
Modifications of these identities (resulting for instance from contributions
localized at orbifold singularities or non-perturbative sources like
five-branes) can then easily be implemented.

</DOC>
<DOC>
<DOCNO> 102143 </DOCNO>
Symplectic rigidity for Anosov hypersurfaces


  We show, using standard results in length spectrum rigidity and symplectic
homology, that if the unit tangent bundles of two compact surfaces of negative
curvature are exact symplectomorphic, then the underlying surfaces are
isometric, and hence the disk bundles are symplectomorphic smoothly up to the
boundaries. Motivated by the work of Eliashberg and Hofer on unseen symplectic
boundaries, we try to extend the above result to other classes of domains in
(co)tangent bundles of surfaces. The domains we can treat consist of those
bounded by deformations of negatively curved unit cotangent bundles through
boundaries with Anosov characteristic (Reeb) flows. We show that if two such
are exact symplectomorphic, then the two domains are symplectomorphic by a
diffeomorphism smooth up to the boundary. Furthermore, if two such surfaces
have the same marked length spectrum then they are connected by a 1-parameter
family of domains bounded by hypersurfaces with smoothly time preserving
conjugate Reeb flows by a smooth family of Hamiltonian diffeomorphisms. A few
counterexamples to easy generalizations are given.

</DOC>
<DOC>
<DOCNO> 8770 </DOCNO>
Schematic phase diagram and collective excitations in the collisional


  We discuss the ground state and the small-amplitude excitations of dilute
boson-fermion mixtures confined in spherical harmonic traps at $T = 0$,
assuming repulsive boson-boson interactions and with each component being in a
single hyperfine state. From previous studies of the equilibrium density
profiles we propose a schematic phase diagram in a plane defined by the
variables $a_{bf}/a_{bb}$ and $a_{bb}k_f^{(0)}$, where $a_{bb}$ and $a_{bf}$
are the boson-boson and boson-fermion scattering lengths and $k_f^{(0)}$ is the
Fermi wave number at the centre of the trap. With this background we turn to
the equations of motion for density fluctuations in the collisional regime and
discuss some general features of the eigenmodes. We display analytic solutions
for sound waves in a quasi-homogeneous mixture and for surface modes at weak
fermion-boson coupling.

</DOC>
<DOC>
<DOCNO> 10899 </DOCNO>
The Maximal Kinematical Invariance Group of Fluid Dynamics and


  It has recently been found that supernova explosions can be simulated in the
laboratory by implosions induced in a plasma by intense lasers. A theoretical
explanation is that the inversion transformation, ($\Sigma: t \to -1/t,~ {\bf
x}\to {\bf x}/t$), leaves the Euler equations of fluid dynamics, with standard
polytropic exponent, invariant. This implies that the kinematical invariance
group of the Euler equations is larger than the Galilei group. In this paper we
determine, in a systematic manner, the maximal invariance group ${\cal G}$ of
general fluid dynamics and show that it is a semi-direct product ${\cal G} =
SL(2,R) \wedge G$, where the $SL(2,R)$ group contains the time-translations,
dilations and the inversion $\Sigma$, and $G$ is the static (nine-parameter)
Galilei group. A subtle aspect of the inclusion of viscosity fields is
discussed and it is shown that the Navier-Stokes assumption of constant
viscosity breaks the $SL(2, R)$ group to a two-parameter group of time
translations and dilations in a tensorial way. The 12-parameter group ${\cal
G}$ is also known to be the maximal invariance group of the free Schr\"odinger
equation. It originates in the free Hamilton-Jacobi equation which is central
to both fluid dynamics and the Schr\"odinger equation.

</DOC>
<DOC>
<DOCNO> 71806 </DOCNO>
Strangeness Content in the Nucleon


  I review recent studies of strangeness content in the nucleon pertaining to
the flavor-singlet $g_A^0$, the $\bar{s}s$ matrix element and the strangeness
electric and magnetic form factors $G_E^s(q^2)$ and $G_M^s(q^2)$, based on
lattice QCD calculations. I shall also discuss the relevance of incorporating
the strangeness content in nuclei in regard to strange baryon-antibaryon
productions from proton-nucleus and nucleus-nucleus collisions at SPS and RHIC
energies.

</DOC>
<DOC>
<DOCNO> 178732 </DOCNO>
Improvement of the extended P+QQ interaction by modifying the monopole


  The extended pairing plus $QQ$ interaction with the $J$-independent isoscalar
proton-neutron force as an average monopole field, which has succeeded in
describing collective yrast states of $N \approx Z$ even-$A$ nuclei, is
improved.
 The improvement is accomplished by adding small monopole terms
 (relevant to spectroscopy) to the average monopole field
 (indispensable to the binding energy). This modification extends the
applicability of the interaction to nuclei with $N \approx 28$ such as
$^{48}$Ca, and moreover improves energy levels of noncollective states.
 The modified interaction successfully describes not only even-$A$ but also
odd-$A$ nuclei in the $f_{7/2}$ shell region.
  Results of exact shell model calculations in the model space
 ($f_{7/2}$, $p_{3/2}$, $p_{1/2}$) (its usefulness has been demonstrated
previously) are shown for $A$=47, 48, 49, 50 and 51 nuclei.

</DOC>
<DOC>
<DOCNO> 69758 </DOCNO>
Precision Studies of Duality in the 't Hooft Model


  We address numerical aspects of local quark-hadron duality using the example
of the exactly solvable 't Hooft model, two-dimensional QCD with N_c -->
infinity. The primary focus of these studies is total semileptonic decay widths
relevant for extracting |V_{cb}| and |V_{ub}|. We compare the exact
channel-by-channel sum of exclusive modes to the corresponding rates obtained
in the standard 1/m_Q expansion arising from the Operator Product Expansion. An
impressive agreement sets in unexpectedly early, immediately after the
threshold for the first hadronic excitation in the final state. Yet even at
higher energy release it is possible to discern the seeds of duality-violating
oscillations. We find the ``Small Velocity'' sum rules to be exceptionally well
saturated already by the first excited state. We also obtain a convincing
degree of duality in the differential distributions and in an analogue of
R_{e^+e^-}(s). Finally, we discuss possible lessons for semileptonic decays of
actual heavy quarks in QCD.

</DOC>
<DOC>
<DOCNO> 85408 </DOCNO>
Light propagation around a relativistic vortex flow of dielectric medium


  We determine the path of the light around a dielectric vortex described by
the relativistic vortex flow of a perfect fluid.

</DOC>
<DOC>
<DOCNO> 39769 </DOCNO>
Underground Muon Physics with the MACRO experiment


  Underground muon events detected by the MACRO experiment at Gran Sasso have
been studied for different purposes. The studies include the vertical muon
intensity measurement, multiplicity distribution, lateral and angular muon
distribution and searches for substructures inside muon bundles. These analyses
have contributed to bring new insights in cosmic ray physics, in particular in
the framework of primary cosmic ray composition studies. Moreover, this
activity allows the testing and tuning of Monte Carlo simulations, in
particular for aspects associated with models of hadronic interactions and muon
propagation through the rock.

</DOC>
<DOC>
<DOCNO> 67654 </DOCNO>
The MSSM at present and future colliders


  A brief overview over the phenomenology of the MSSM at present and future
colliders is given. The complementarity of indirect tests of the model via
precision observables and of the information from the direct production of SUSY
particles is emphasized. If the lightest Higgs boson of the MSSM will be
detected, its mass will also play an important role as a precision observable.

</DOC>
<DOC>
<DOCNO> 68896 </DOCNO>
Subleading Sudakov logarithms in electroweak high energy processes to


  In future collider experiments at the TeV scale, large logarithmic
corrections originating from massive boson exchange can lead to significant
corrections to observable cross sections. Recently double logarithms of the
Sudakov-type were resummed for spontaneously broken gauge theories and found to
exponentiate. In this paper we use the virtual contributions to the
Altarelli-Parisi splitting functions to obtain the next to leading order kernel
of the infrared evolution equation in the fixed angle scattering regime at high
energies where particle masses can be neglected. In this regime the virtual
corrections can be described by a generalized renormalization group equation
with infrared singular anomalous dimensions. The results are valid for virtual
electroweak corrections to fermions and transversely polarized vector bosons
with an arbitrary number of external lines. The subleading terms are found to
exponentiate as well and are related to external lines, allowing for a
probabilistic interpretation in the massless limit. For $Z$-boson and $\gamma$
final states our approach leads to exponentiation with respect to each
amplitude containing the fields of the unbroken theory. For longitudinal
degrees of freedom it is shown that the equivalence theorem can be used to
obtain the correct double logarithmic asymptotics. At the subleading level,
corrections to the would be Goldstone bosons contribute which should be
considered separately. Explicit comparisons with existing one loop calculations
are made.

</DOC>
<DOC>
<DOCNO> 69376 </DOCNO>
Finding eta_c' and h_c at HERA-B


  The production of Charmonium states $\etacp$ and $\hc$ at fixed-target
experiment of $pN$ collisions at HERA-$B$ is considered. It is found that the
HERA-$B$ at DESY is one of the best machines in further confirming and
detecting these two kinds of Charmonia in the near future.

</DOC>
<DOC>
<DOCNO> 68769 </DOCNO>
Extending the Frontiers - Reconciling Accelerator and Cosmic Ray p-p


  We simultaneously fit a QCD-inspired parameterization of all accelerator data
on forward proton-proton and antiproton-proton scattering amplitudes, together
with cosmic ray data (using Glauber theory), to predict proton-air and
proton-proton cross sections at energies near \sqrt s \approx 30 TeV. The p-air
cosmic ray measurements provide a strong constraint on the inclusive particle
production cross section, as well as greatly reducing the errors on the fit
parameters---in turn, greatly reducing the errors in the high energy
proton-proton and proton-air cross section predictions.

</DOC>
<DOC>
<DOCNO> 68975 </DOCNO>
A Novel Possibility to Determine the CP-violating Phase \gamma and the


  We show that a CP-violating phase can be model-independently determined from
the time-independent measurement of coherent B^0_s\bar{B}^0_s decays into
(D^{(*)\pm}_s K^{(*)\mp})(D^{(*)\pm}_s K^{(*)\mp}) states at the \Upsilon (5S)
resonance. This phase amounts to (-\gamma) within the standard model, where
\gamma is the well-known angle of the quark mixing unitarity triangle. It is
also possible to determine or constrain the B^0_s-\bar{B}^0_s mixing parameter
y_s from the same measurement.

</DOC>
<DOC>
<DOCNO> 118220 </DOCNO>
Detection of deuterium Balmer lines in the Orion Nebula


  The detection and first identification of the deuterium Balmer emission
lines, D-alpha and D-beta, in the core of the Orion Nebula is reported.
Observations were conducted at the 3.6m Canada-France-Hawaii Telescope, using
the Echelle spectrograph Gecko. These lines are very narrow and have identical
11 km/s velocity shifts with respect to H-alpha and H-beta. They are probably
excited by UV continuum fluorescence from the Lyman (DI) lines and arise from
the interface between the HII region and the molecular cloud.

</DOC>
<DOC>
<DOCNO> 8870 </DOCNO>
Compressibility crossover and quantum opening of a gap for two


  Using Hartree-Fock orbitals with residual Coulomb repulsion, we study
spinless fermions in a two dimensional random potential. When we increase the
system size $L$ at fixed particle density, the size dependence of the average
inverse compressibility exhibits a smooth crossover from a $1/L^2$ towards a
1/L decay when the Coulomb energy to Fermi energy ratio $r_s$ increases from 0
to 3. In contrast, the distribution of the first energy excitation displays a
sharp Poisson-Wigner-like transition at $r_s \approx 1$.

</DOC>
<DOC>
<DOCNO> 11640 </DOCNO>
A transfer matrix approach to the enumeration of plane meanders


  A closed plane meander of order $n$ is a closed self-avoiding curve
intersecting an infinite line $2n$ times. Meanders are considered distinct up
to any smooth deformation leaving the line fixed. We have developed an improved
algorithm, based on transfer matrix methods, for the enumeration of plane
meanders. While the algorithm has exponential complexity, its rate of growth is
much smaller than that of previous algorithms. The algorithm is easily modified
to enumerate various systems of closed meanders, semi-meanders, open meanders
and many other geometries.

</DOC>
<DOC>
<DOCNO> 122025 </DOCNO>
A sample of 6C radio sources with virtually complete redshifts. II -


  This is the second of two papers presenting basic observational data on the
6CE sample of extragalactic radio sources. It presents the results of optical
spectroscopy which has yielded virtually complete redshift information for the
6CE sample: 56 of the 59 sample members have spectroscopic redshifts which,
with the exception of seven cases, are secure. The redshift distribution N(z)
is fairly flat over the redshift range 0 < z < 2, with a median redshift of 1.1
and a high-redshift tail reaching to z = 3.4. The highest-redshift (z > 1.75)
members of the 6CE sample have similar optical spectra and a tight (less than
one dex) spread in narrow-Lyalpha emission line luminosity.

</DOC>
<DOC>
<DOCNO> 85218 </DOCNO>
Unimodular relativity and cosmological constant


  Unimodular relativity is a theory of gravity and space-time with a fixed
absolute space-time volume element, the modulus, which we suppose is
proportional to the number of microscopic modules in that volume element. In
general relativity an arbitrary fixed measure can be imposed as a gauge
condition, while in unimodular relativity it is determined by the events in the
volume. Since this seems to break general covariance, some have suggested that
it permits a non-zero covariant divergence of the material stress-energy tensor
and a variable cosmological ``constant.'' In Lagrangian unimodular relativity,
however, even with higher-derivatives of the gravitational field in the
dynamics, the usual covariant continuity holds and the cosmological constant is
still a constant of integration of the gravitational field equations.

</DOC>
<DOC>
<DOCNO> 71696 </DOCNO>
Naturally Small Seesaw Neutrino Mass with No New Physics Beyond the TeV


  If there is no new physics beyond the TeV energy scale, such as in a theory
of large extra dimensions, the smallness of the seesaw neutrino mass, i.e.
$m_\nu = m_D^2/m_N$, cannot be explained by a very large $m_N$. In contrast to
previous attempts to find an alternative mechanism for a small $m_\nu$, I show
how a solution may be obtained in a simple extension of the Standard Model,
without using any ingredient supplied by the large extra dimensions. It is also
experimentally testable at future accelerators.

</DOC>
<DOC>
<DOCNO> 11056 </DOCNO>
Integrated random processes exhibiting long tails, finite moments and


  A dynamical model based on a continuous addition of colored shot noises is
presented. The resulting process is colored and non-Gaussian. A general
expression for the characteristic function of the process is obtained, which,
after a scaling assumption, takes on a form that is the basis of the results
derived in the rest of the paper. One of these is an expansion for the
cumulants, which are all finite, subject to mild conditions on the functions
defining the process. This is in contrast with the Levy distribution -which can
be obtained from our model in certain limits- which has no finite moments. The
evaluation of the power spectrum and the form of the probability density
function in the tails of the distribution shows that the model exhibits a 1/f
spectrum and long tails in a natural way. A careful analysis of the
characteristic function shows that it may be separated into a part representing
a Levy processes together with another part representing the deviation of our
model from the Levy process. This allows our process to be viewed as a
generalization of the Levy process which has finite moments.

</DOC>
<DOC>
<DOCNO> 7777 </DOCNO>
Extensive infrared spectroscopic study of CuO: signatures of strong


  Optical properties of single-crystal monoclinic CuO in the range 70 - 6000
\cm were studied at temperatures from 7 to 300 K. Normal reflection spectra
were obtained from the (001) and (010) crystal faces thus giving for the first
time separate data for the $A_{u}$ and $B_{u}$ phonon modes excited in the
purely transverse way (TO modes). Mode parameters, including polarizations of
the $B_{u}$ modes not determined by the crystal symmetry, were extracted by the
dispersion analysis of reflectivity curves as a function of temperature.
Spectra of all the components of the optical conductivity tensor were obtained
using the Kramers-Kronig method recently extended to the case of the
low-symmetry crystals. The number of strong phonon modes is in agreement with
the factor-group analysis for the crystal structure, currently accepted for the
CuO. However, several "extra" modes of minor intensity are detected. Comparison
of frequencies of "extra" modes with the available phonon dispersion curves
points to possible "diagonal" doubling of the unit cell \{{\bf a}, {\bf b},
{\bf c}\} $\to$ \{{\bf a}+{\bf c}, {\bf b}, {\bf a}-{\bf c}\} and formation of
the superlattice. The previously reported softening of the $A^{3}_{u}$ mode
($\sim$ 400 \cm) with cooling at $T_{N}$ is found to be $\sim$ 10 % for the TO
mode. The mode is very broad at high temperatures and strongly narrows in the
AFM phase. We attribute this effect to strong resonance coupling of this mode
to optical or acoustic bi-magnons and reconstruction of the magnetic
excitations spectrum at the N\'eel point. A significant anisotropy of
$\epsilon^{\infty}$ is observed: it was found to be 5.9 along the {\bf b}-axis,
6.2 along the {[}101{]} chains and 7.8 the {[}10$\bar{1}${]} chains. The
"transverse" effective charge is value is about 2 electrons.

</DOC>
<DOC>
<DOCNO> 71908 </DOCNO>
One-loop QCD corrections to quark scattering at NNLO


  We present the O(as^4) virtual QCD corrections to unlike-quark and like-quark
scattering due to the interference of one-loop amplitudes with one-loop
amplitudes. The structure of the infrared divergences agrees with that
predicted by Catani. The results are expressed in an analytic form so that the
relevant expressions for crossed scattering processes can be obtained in a
straightforward manner. The one-loop contributions presented here, together
with the interference of tree with two-loop amplitudes given recently, complete
the 2 to 2 virtual QCD corrections at NNLO for the massless quark scattering
processes.

</DOC>
<DOC>
<DOCNO> 68122 </DOCNO>
Can the Inflaton and the Quintessence scalar be the same field?


  The most recent cosmological data point in the direction of a cosmological
constant dominated universe. A suitable candidate for providing the required
acceleration is a rolling scalar field named ``quintessence''. We address the
issue of building a particle physics model for quintessence in the context of
Susy QCD. We then go on to ask if the quintessence scalar can be identified
with the inflaton field and give two examples in which this is indeed the case.

</DOC>
<DOC>
<DOCNO> 8173 </DOCNO>
Demixing in binary mixtures of hard hyperspheres


  The phase behavior of binary fluid mixtures of hard hyperspheres in four and
five dimensions is investigated. Spinodal instability is found by using a
recent and accurate prescription for the equation of state of the mixture that
requires the equation of state of the single component fluid as input. The role
played by the dimensionality on the possible metastability of the demixing
transition with respect to a fluid-solid transition is discussed. The binodal
curves in the pressure--chemical potential representation are seen to lie on a
common line, independent of the size ratio

</DOC>
<DOC>
<DOCNO> 169625 </DOCNO>
Noncommutative analysis and quantum physics I. Quantities, ensembles and


  A unified conceptual foundation of classical and quantum physics is given,
free of undefined terms.
  Ensembles are defined by extending the `probability via expectation' approach
of Whittle to noncommuting quantities. This approach carries no connotations of
unlimited repeatability; hence it can be applied to unique systems such as the
universe. Precise concepts and traditional results about complementarity,
uncertainty and nonlocality follow with a minimum of technicalities.
Probabilities are introduced in a generality supporting so-called effects
(i.e., fuzzy events).
  States are defined as partial mappings that provide reference values for
certain quantities. An analysis of sharpness properties yields well-known no-go
theorems for hidden variables. By dropping the sharpness requirement, hidden
variable theories such as Bohmian mechanics can be accommodated, but so-called
ensemble states turn out to be a more natural realization of a realistic state
concept. The weak law of large numbers explains the emergence of classical
properties for macroscopic systems.

</DOC>
<DOC>
<DOCNO> 8952 </DOCNO>
Resonant tunnelling and quenching of tunnel splitting in Wess-Zumino


  We investigate the energy spectrum of the biaxial spin systems with magnetic
field along the hard anisotropy axis by using the complex periodic orbit
theory. All important features of the system appearing in whole energy range,
such as oscillations of level splittings due to Wess-Zumino effect and their
absence at higher magnetic field etc., can be completely understood within this
semiclassical scheme. We find out that the fields at which the tunnelling
quenches do not shift at higher energy levels and the absences of the quenching
at higher magnetic field have their origin in an exact coincidence of the
quenching field with the field of resonant tunnelling. Based on the result, we
propose that the complete cancellation of quenching with resonant tunnelling
would be a general property of Wess-Zumino tunnelling systems.

</DOC>
<DOC>
<DOCNO> 9185 </DOCNO>
Enhanced stability of layered phases in parallel hard-spherocylinders


  There is increasing evidence that entropy can induce microphase separation in
binary fluid mixtures interacting through hard particle potentials. One such
phase consists of alternating two dimensional liquid-like layers of rods and
spheres. We study the transition from a uniform miscible state to this ordered
state using computer simulations and compare results to experiments and theory.
We conclude that (1) there is stable entropy driven microphase separation in
mixtures of parallel rods and spheres, (2) adding spheres smaller then the rod
length decreases the total volume fraction needed for the formation of a
layered phase, therefore small spheres effectively stabilize the layered phase;
the opposite is true for large spheres and (3) the degree of this stabilization
increases with increasing rod length.

</DOC>
<DOC>
<DOCNO> 120211 </DOCNO>
Infrared interferometric observations of young stellar objects


  We present infrared observations of four young stellar objects using the
Palomar Testbed Interferometer (PTI). For three of the sources, T Tau, MWC 147
and SU Aur, the 2.2 micron emission is resolved at PTI's nominal fringe spacing
of 4 milliarcsec (mas), while the emission region of AB Aur is over-resolved on
this scale. We fit the observations with simple circumstellar material
distributions and compare our data to the predictions of accretion disk models
inferred from spectral energy distributions. We find that the infrared emission
region is tenths of AU in size for T Tau and SU Aur and ~1 AU for MWC 147.

</DOC>
<DOC>
<DOCNO> 116404 </DOCNO>
The Flotational Mechanism of Etobicoke Creek's Self-Purification


  A flotational mechanism of Etobicoke Creek's self-purification has been
investigated. It is shown that the froth contains a high concentration of
polluting agents. Chemical analyses of the top layer of surface water in
comparison to both before and after froth collector in the course of a year are
provided. As a result, the concentrations of pollutants by utilizing the model
froth collector are decreased.

</DOC>
<DOC>
<DOCNO> 178740 </DOCNO>
Dirac-Brueckner Approach to Hyperon Interactions and Hypernuclei


  The density dependent relativistic hadron (DDRH) theory is introduced as an
effective field theory for nuclei and hypernuclei. A Dirac-Brueckner approach
to in-medium nucleon-hyperon interactions is presented. Density dependent
meson-baryon vertices are determined from DBHF self-energies in infinite
matter. Scaling laws for hyperon vertices are derived from a diagrammatic
analysis of self-energies. In a local density approximation the DB vertices are
applied in relativistic DDRH Hartree calculations to finite hypernuclei. Lambda
single particle spectra and spin-orbit splittings are described reasonably well
over the whole mass region.

</DOC>
<DOC>
<DOCNO> 123126 </DOCNO>
The Brown Dwarf Mass Function from Pixel Microlensing


  We argue that gravitational microlensing is a feasible technique for
measuring the mass function of brown dwarf stars in distant galaxies.
Microlensing surveys of the bulge of M31, and of M87 in the Virgo cluster, may
provide enough events to differentiate the behaviour of the mass function of
lenses below the hydrogen burning limit (though we find that M87 is a more
favourable target). Such objects may provide a significant supply of baryonic
dark matter, an interesting possibility for the study of galactic dynamics.
Furthermore, these systems have different metallicities than the solar
neighbourhood, which may affect the mass function. These considerations are
relevant in the context of star formation studies.

</DOC>
<DOC>
<DOCNO> 10971 </DOCNO>
Spin-lattice relaxation in the mixed state of the high-$T_c$ cuprates:


  Recent experimental and theoretical studies have established that the
spin-lattice relaxation rate, $1/T_1$, measured in nuclear magnetic resonance
(NMR) experiments is a site-sensitive probe for the electronic spectrum in the
mixed state of the high-$T_c$ cuprates. While some groups suggested that
$1/T_1$ is solely determined by spin-flip scattering of BCS-like electrons,
other groups stressed the importance of antiferromagnetic spin-fluctuations. We
show that these two relaxation mechanisms give rise to a {\it qualitatively}
different temperature and frequency dependence of $^{17}$O $1/T_1$. A
comparison of our results with the experimental $^{17}$O $1/T_1$ data provides
support for a relaxation mechanism dominated by antiferromagnetic
spin-fluctuations.

</DOC>
<DOC>
<DOCNO> 84756 </DOCNO>
Note on Small Black Holes in AdS_p x S^q


  It is commonly believed that small black holes in AdS_5 x S^5 can be
described by the ten dimensional Schwarzschild solution. This requires that the
self-dual five-form (which is nonzero in the background) does not fall through
the horizon and cause the black hole to grow. We verify that this is indeed the
case: There are static solutions to the five-form field equations in a ten
dimensional Schwarzschild spacetime. Similar results hold for other backgrounds
AdS_p x S^q of interest in supergravity.

</DOC>
<DOC>
<DOCNO> 122695 </DOCNO>
Hydrodynamical simulations of the Sunyaev-Zel'dovich effect: the kinetic


  We use hydrodynamical N-body simulations to study the kinetic
Sunyaev-Zel'dovich effect. We construct sets of maps, one square degree in
size, in three different cosmological models. We confirm earlier calculations
that on the scales studied the kinetic effect is much smaller than the thermal
(except close to the thermal null point), with an rms dispersion smaller by
about a factor five in the Rayleigh-Jeans region. We study the redshift
dependence of the rms distortion and the pixel distribution at the present
epoch. We compute the angular power spectra of the maps, including their
redshift dependence, and compare them with the thermal Sunyaev-Zel'dovich
effect and with the expected cosmic microwave background anisotropy spectrum as
well as with determinations by other authors. We correlate the kinetic effect
with the thermal effect both pixel-by-pixel and for identified thermal sources
in the maps to assess the extent to which the kinetic effect is enhanced in
locations of strong thermal signal.

</DOC>
<DOC>
<DOCNO> 178526 </DOCNO>
The alpha-particle in nuclear matter


  Among the light nuclear clusters the alpha-particle is by far the strongest
bound system and therefore expected to play a significant role in the dynamics
of nuclei and the phases of nuclear matter. To systematically study the
properties of the alpha-particle we have derived an effective four-body
equation of the Alt-Grassberger-Sandhas (AGS) type that includes the dominant
medium effects, i.e. self energy corrections and Pauli-blocking in a consistent
way. The equation is solved utilizing the energy dependent pole expansion for
the sub system amplitudes. We find that the Mott transition of an
alpha-particle at rest differs from that expected from perturbation theory and
occurs at approximately 1/10 of nuclear matter densities.

</DOC>
<DOC>
<DOCNO> 117631 </DOCNO>
Closing the gap: an X-ray selected sample of clusters of galaxies behind


  We discuss the design and current status of the CIZA survey, the first
systematic X-ray search for clusters of galaxies in the Galactic plane region.
So far, we have compiled a sample of more than 70 X-ray selected clusters at
|b|<20 deg, 80% of which were previously unknown. Upon its completion the CIZA
cluster catalogue will complement the existing galaxy surveys in the Galactic
plane region and allow a fresh look at large-scale structure and local
streaming motions.

</DOC>
<DOC>
<DOCNO> 80718 </DOCNO>
Fermion doubling problem and noncommutative geometry II


  In our previous paper (hep-th/9911087), we proposed a resolution for the
fermion doubling problem in discrete field theories based on the fuzzy sphere
and its cartesian products. In this paper after a review of that work, we bring
out its relationship to the Ginsparg-Wilson approach.

</DOC>
<DOC>
<DOCNO> 117876 </DOCNO>
Formation and evolution of disk galaxies within cold dark matter halos


  We present results of extensive model calculations of disk galaxy evolution
within an hierarchical inside-out formation scenario. We first compare
properties of the dark halos identified in a cosmological N-body simulation
with predictions of a seminumerical method based on an extended collapse model
and find a good agreement. We also study the properties of the halos in
dependence on their environment. We then describe detailed modelling of the
formation and evolution of disks within the growing isolated cold dark matter
halos and predictions for the main properties, correlations and evolutionary
features of normal disk galaxies. The possible shortcomings of the scenario are
discussed.

</DOC>
<DOC>
<DOCNO> 122220 </DOCNO>
Metal Enrichment and Temperature of the Intergalactic Medium


  Hydrodynamic simulations of Lyman alpha clouds based on ab inito cosmological
models have produced results that are in broad agreement with observations.
However, further analyses have revealed that, with progressively higher
numerical resolution, the median or cutoff line width of the simulated Lyman
alpha clouds (i.e. the Doppler parameter) appears to converge to a value
significantly below what is observed at z~3 (by about a factor of 1.5). These
convergence test simulations do not include feedback from star formation. Given
the observed metallicity in the Lyman alpha clouds we suggest that supernovae,
which presumably polluted the IGM with metals, may have deposited a sufficient
amount of energy in the IGM to reconcile the theory with observations. Simple
arguments immediately narrow the redshift range of pollution down to
4<z_{dep}<9. It seems quite certain that dwarf and sub-dwarf galaxies with
total masses in the range 10^{6.5-9.0}Msun have to be largely responsible for
the pollution. Furthermore, it is implied that either star formation is very
efficient or metal yield is very high for these early dwarf galaxies, if the
mean metallicity in the universe at z=3 is as high as <Z>=0.01Zsun. Finally,
assuming the specific supernova heating energy is proportional to the
metallicity of a gas, we note that the picture proposed here would be
consistent with supernovae being the apparently needed heating source for the
intra-cluster gas, if the required heating of the intra-cluster gas is no
greater than 1 keV per particle.

</DOC>
<DOC>
<DOCNO> 68098 </DOCNO>
Quark Coulomb Interactions and the Mass Difference of Mirror Nuclei


  We study the Okamoto-Nolen-Schiffer (ONS) anomaly in the binding energy of
mirror nuclei at high density by adding a single neutron or proton to a quark
gluon plasma. In this high-density limit we find an anomaly equal to two-thirds
of the Coulomb exchange energy of a proton. This effect is dominated by quark
electromagnetic interactions---rather than by the up-down quark mass
difference. At normal density we calculate the Coulomb energy of neutron matter
using a string-flip quark model. We find a nonzero Coulomb energy because of
the neutron's charged constituents. This effect could make a significant
contribution to the ONS anomaly.

</DOC>
<DOC>
<DOCNO> 99412 </DOCNO>
Veronese webs for bihamiltonian structures of higher corank


  It is shown how the well-known class of bihamiltonian structures in general
position can be extended to a wider class. A generalization of the
corresponding notion of a Veronese web for this wider class is presented (in
the general position case Veronese webs form complete systems of local
invariants for bihamiltonian structures). Some examples are considered.

</DOC>
<DOC>
<DOCNO> 11313 </DOCNO>
Localization-Delocalization Transition of Electron States in a


  We investigate the localization behavior of electrons in a random lattice
which is constructed from a quasi-one-dimensional chain with large coordinate
number $Z$ and rewired bonds, resembling the small-world network proposed
recently but with site-energy disorder and quantum links instead of classical
ones. The random rewiring of bonds in the chain with large $Z$ enhances both
the topological disorder and the effective dimensionality. From the competition
between disorder and dimensionality enhancement a transition from localization
to delocalization is found by using the level statistics method combined with
the finite-size scaling analysis. The critical value of the rewiring rate for
this transition is determined numerically. We obtain a universal critical
integrated distribution of level spacing $s$ in the form $I_{p_{c}}(s)\propto
\exp (-A_{c}s^{\alpha})$, with $A_{c}\simeq 1.50$ and $\alpha \simeq 1.0$. This
reveals the possible existence of metal-insulator transition in materials with
chains as the backbones.

</DOC>
<DOC>
<DOCNO> 80796 </DOCNO>
The gluon condensate from gauge invariant vortex vacuum texture


  In SU(2) lattice gauge theory, a new self-restricted cooling procedure is
developed to uncover the gauge invariant vortex vacuum texture. The emerging
vortex vacuum structure amounts to the full string tension and gives rise to a
mass dimension four condensate which is of pure vortex origin.

</DOC>
<DOC>
<DOCNO> 11781 </DOCNO>
Finite Size Effects in Small Particle Systems


  We present the results of Monte Carlo simulations of a model of a
$\gamma$-Fe$_2$ O$_3$ (maghemite) single particle of spherical shape. The
magnetic Fe$^{3+}$ ions are represented by Ising spins on a spinel lattice that
consists on two sublattices with octhaedral and tetrahedral coordination with
exchange interactions among them and with an external magnetic field. By
varying the particle diameter, we have studied the influence of the finite size
of the particle on the equilibrium properties, field cooling magnetization and
hysteresis loops. The simulations allow to distinguish the different roles
played by the surface and the core spins of the particle on its magnetic
properties. We show that for small particle sizes the core is uncoupled from
the surface, that behaves as a quasi-independent layer, whereas for bigger
particles the surface and the core are coupled and follow the behaviour of the
bulk.

</DOC>
<DOC>
<DOCNO> 151333 </DOCNO>
Global calculus in BRST cohomology


  The iterated BRST cohomology is studied by computing cohomology of the
variational complex on the infinite order jet space of a smooth fibre bundle.
This computation also provides a solution of the global inverse problem of the
calculus of variations in Lagrangian field theory.

</DOC>
<DOC>
<DOCNO> 11991 </DOCNO>
Solitons in the one-dimensional forest fire model


  Fires in the one-dimensional Bak-Chen-Tang forest fire model propagate as
solitons, resembling shocks in Burgers turbulence. The branching of solitons,
creating new fires, is balanced by the pair-wise annihilation of oppositely
moving solitons. Two distinct, diverging length scales appear in the limit
where the growth rate of trees, $p$, vanishes. The width of the solitons, $w$,
diverges as a power law, $1/p$, while the average distance between solitons
diverges much faster as $ d \sim \exp({\pi}^2/12p)$.

</DOC>
<DOC>
<DOCNO> 8983 </DOCNO>
Striped superconductors in the extended Hubbard model


  We present a minimal model of a doped Mott insulator that simultaneously
supports antiferromagnetic stripes and d-wave superconductivity. We explore the
implications for the global phase diagram of the superconducting cuprates. At
the unrestricted mean-field level, the various phases of the cuprates,
including weak and strong pseudogap phases, and two different types of
superconductivity in the underdoped and the overdoped regimes, find a natural
interpretation. We argue that on the underdoped side, the superconductor is
intrinsically inhomogeneous -- striped coexistence of of superconductivity and
magnetism -- and global phase coherence is achieved through Josephson-like
coupling of the superconducting stripes. On the overdoped side, the state is
overall homogeneous and the superconductivity is of the classical BCS type.

</DOC>
<DOC>
<DOCNO> 13128 </DOCNO>
Josephson vortices and the Meissner effect in stacked junctions and


  We present an exact mathematical description of Josephson vortices and of the
Meissner effect in periodic thin-layer superconductor/insulator structures with
an arbitrary number of identical junctions N-1 (N is the number of
superconducting layers) in terms of localized solutions to a system of
differential equations for phase differences. We establish a general criterion
of the existence of localized solutions. We show that Meissner solutions are
characterized by several Josephson lengths [N/2 lengths for even N, and (N-1)/2
lengths for odd N]. We derive an exact expression for the superheating field of
the Meissner state as an explicit function of N. For Josephson vortices, we
find two basically different types of topological solutions: ''vortex-plane''
solutions and incoherent vortex solutions. Thermodynamically stable
''vortex-plane'' solutions represent a chain of N-1 vortices (one vortex per
each insulating layer). They are characterized by the same set of Josephson
lengths as the Meissner solutions. We obtain exact analytical expressions for
their self-energy and for the lower critical field. Incoherent vortex solutions
comprise solutions with k < N-1 vortices and different vortex-antivortex
configurations. In contrast to the ''vortex-plane'' solutions, they prove to be
thermodynamically unstable, and their spatial dependence is characterized, in
general, by N-1 length scales. As an illustration, we analyze
1-4-Josephson-junction stacks and investigate a transition to the layered
superconductor limit.

</DOC>
<DOC>
<DOCNO> 150959 </DOCNO>
Fermions on the Light-Front


  Issues that are specific for formulating fermions in light-cone quantization
are discussed. Special emphasis is put on the use of parity invariance in the
non-perturbative renormalization of light-cone Hamiltonians.

</DOC>
<DOC>
<DOCNO> 9365 </DOCNO>
Path integrals approach to resisitivity anomalies in anharmonic systems


  Different classes of physical systems with sizeable electron-phonon coupling
and lattice distortions present anomalous resistivity behaviors versus
temperature. We study a molecular lattice Hamiltonian in which polaronic charge
carriers interact with non linear potentials provided by local atomic
fluctuations between two equilibrium sites. We study a molecular lattice
Hamiltonian in which polaronic charge carriers interact with non linear
potentials provided by local atomic fluctuations between two equilibrium sites.
A path integral model is developed to select the class of atomic oscillations
which mainly contributes to the partition function and the electrical
resistivity is computed in a number of representative cases. We argue that the
common origin of the observed resistivity anomalies lies in the time retarded
nature of the polaronic interactions in the local structural instabilities.

</DOC>
<DOC>
<DOCNO> 14145 </DOCNO>
Unipolar spin diodes and transistors


  Unipolar devices constructed from ferromagnetic semiconducting materials with
variable magnetization direction are shown theoretically to behave very
similarly to nonmagnetic bipolar devices such as the p-n diode and the bipolar
(junction) transistor. Such devices may be applicable for magnetic sensing,
nonvolatile memory, and reprogrammable logic.

</DOC>
<DOC>
<DOCNO> 8700 </DOCNO>
Comment on ``Quantum mechanics of an electron in a homogeneous magnetic


  Recently Thienel [Ann. Phys. (N.Y.) 280 (2000), 140; quant-ph/9809047]
investigated the Pauli equation for an electron moving in a plane under the
influence of a perpendicular magnetic field which is the sum of a uniform field
and a singular flux tube. Here we criticise his claim that one cannot properly
solve this equation by treating the singular flux tube as the limiting case of
a flux tube of finite size.

</DOC>
<DOC>
<DOCNO> 101233 </DOCNO>
Supercriticality and Transmission Resonances in the Dirac equation


  It is shown that a Dirac particle of mass $m$ and arbitrarily small momentum
will tunnel without reflection through a potential barrier $V=U_c(x)$ of finite
range provided that the potential well $V=-U_c(x)$ supports a bound state of
energy $E=-m.$ This is called a supercritical potential well.

</DOC>
<DOC>
<DOCNO> 119259 </DOCNO>
The Connection between Globular Cluster Systems and the Host Galaxies


  A large number of early type galaxies are now known to possess blue and red
subpopulations of globular clusters. We have compiled a database of 28 such
galaxies exhibiting bimodal globular cluster colour distributions. After
converting to a common V-I colour system, we investigate correlations between
the mean colour of the blue and red subpopulations with galaxy velocity
dispersion. We support previous claims that the mean colour of the blue
globular clusters are unrelated to their host galaxy. They must have formed
rather independently of the galaxy potential they now inhabit. The mean blue
colour is similar to that for halo globular clusters in our Galaxy and M31. The
red globular clusters, on the other hand, reveal a strong correlation with
galaxy velocity dispersion. Futhermore, in well-studied galaxies the red
subpopulation has similar, and possibly identical, colours to the galaxy halo
stars. Our results indicate an intimate link between the red globular clusters
and the host galaxy; they share a common formation history. A natural
explanation for these trends would be the formation of the red globular
clusters during galaxy collapse.

</DOC>
<DOC>
<DOCNO> 80666 </DOCNO>
Lorentz gauge fixing and lattice QED


  The Gribov ambiguity problem is studied for compact lattice QED within the
Lorentz gauge. In the Coulomb phase, Gribov copies are mainly caused by double
Dirac sheets and zero-momentum modes of the gauge fields. Removing them by
(non-) periodic gauge transformations allows to reach the absolute extremum of
the Lorentz gauge functional. For standard Lorentz gauge fixing the Wilson
fermion correlator turns out to be strongly effected by the zero-momentum
modes. A reliable fermion mass estimate requires the proper treatment of these
modes.

</DOC>
<DOC>
<DOCNO> 9096 </DOCNO>
Intertube coupling in ropes of single-wall carbon nanotubes


  We investigate the coupling between individual tubes in a rope of single-wall
carbon nanotubes using four probe resistance measurements. By introducing
defects through the controlled sputtering of the rope we generate a strong
non-monotonic temperature dependence of the four terminal resistance. This
behavior reflects the interplay between localization in the intentionally
damaged tubes and coupling to undamaged tubes in the same rope. Using a simple
model we obtain the coherence length and the coupling resistance. The coupling
mechanism is argued to involve direct tunneling between tubes.

</DOC>
<DOC>
<DOCNO> 170295 </DOCNO>
Error correction for mutually interacting qubits


  For a simple model of mutually interacting qubits it is shown how the errors
induced by mutual interactions can be eliminated using concatenated coding. The
model is solved exactly for arbitrary interaction strength, for two well-known
codes, one and two levels deep: this allows one to see under which
circumstances error amplitudes add coherently or incoherently. For deeper
concatenation, approximate results are derived which make it possible to
calculate an approximate ``threshold'' value for the product of interaction
strength and free evolution time, below which the failure probability for an
encoded qubit decreases exponentially with the depth of the encoding. The
results suggest that concatenated coding could fully handle the errors arising
from mutual interactions, at no extra cost, in terms of resources needed, from
what would be required to deal with random environmental errors.

</DOC>
<DOC>
<DOCNO> 118158 </DOCNO>
The Dependence of the Age Parameter from EAS Size and Zenith Angle of


  The quality of the MAKET-ANI detector installation in view of the uniformity
of the registration efficiency is demonstrated. Based on a data sample
collected by the MAKET-ANI array in the period of June 1997 - March 1999, the
dependencies of the age parameter on the zenith angle and the EAS size
(10^5-10^7) are studied. The variation of the age parameter with the shower
size can be approximately related to the elongation rate.

</DOC>
<DOC>
<DOCNO> 10332 </DOCNO>
On the computational capabilities of physical systems part II:


  In the first of this pair of papers, it was proven that that no physical
computer can correctly carry out all computational tasks that can be posed to
it. The generality of this result follows from its use of a novel definition of
computation, ``physical computation''. This second paper of the pair elaborates
the mathematical structure and impossibility results associated with physical
computation. Analogues of Chomsky hierarcy results concerning universal Turing
Machines and the Halting theorem are derived, as are results concerning the
(im)possibility of certain kinds of error-correcting codes. In addition, an
analogue of algorithmic information complexity, ``prediction complexity'', is
elaborated. A task-independent bound is derived on how much the prediction
complexity of a computational task can differ for two different universal
physical computers used to solve that task, a bound similar to the ``encoding''
bound governing how much the algorithm information complexity of a Turing
machine calculation can differ for two universal Turing machines. Finally, it
is proven that either the Hamiltonian of our universe proscribes a certain type
of computation, or prediction complexity is unique (unlike algorithmic
information complexity).

</DOC>
<DOC>
<DOCNO> 69091 </DOCNO>
Constraints on Vacuum Oscillations from Recent Solar Neutrino Data


  A detailed study of the solar neutrino vacuum oscillation was made taking
into account three neutrino flavours and the seasonal effect. This analysis was
established for a range of the mixing parameter sin^2(2\phi), that is concerned
with the electron-tau neutrino oscillations, from 0 to 1. We obtained the
allowed mass regions versus mixing angles by fitting only the rates of the five
solar neutrino detectors in activity and we compared with the fits including
the recoil-electron spectrum of the Kamiokande and Super-Kamiokande
experiments. The averaged survival probabilities for electron neutrinos as a
function of the neutrino energy are also obtained, showing that the solutions
for sin^2(2\phi) greater than 0.50 with the maximum exclusion of Be7 neutrinos
and the minimum exclusion of pp neutrinos give a better explanation for the
suppression rates of all detectors.

</DOC>
<DOC>
<DOCNO> 11083 </DOCNO>
On the Effects of a Bulk Perturbation on the Ground State of 3D Ising


  We compute and analyze couples of ground states of 3D spin glasses before and
after applying a volume perturbation which adds to the Hamiltonian a repulsion
from the true ground state. The physical picture based on Replica Symmetry
Breaking is in excellent agreement with the observed behavior.

</DOC>
<DOC>
<DOCNO> 11658 </DOCNO>
Mobility Edge in Aperiodic Kronig-Penney Potentials with Correlated


  It is shown that a non-periodic Kronig-Penney model exhibits mobility edges
if the positions of the scatterers are correlated at long distances. An
analytical expression for the energy-dependent localization length is derived
for weak disorder in terms of the real-space correlators defining the
structural disorder in these systems. We also present an algorithm to construct
a non-periodic but correlated sequence exhibiting desired mobility edges. This
result could be used to construct window filters in electronic, acoustic, or
photonic non-periodic structures.

</DOC>
<DOC>
<DOCNO> 7756 </DOCNO>
Spin-dynamic field coupling in strongly THz driven semiconductors :


  We study theoretically the optics in undoped direct gap semiconductors which
are strongly driven in the THz regime. We calculate the optical sideband
generation due to nonlinear mixing of the THz field and the near infrared
probe. Starting with an inversion symmetric microscopic Hamiltonian we include
the THz field nonperturbatively using non-equilibrium Green function
techniques. We find that a self induced relativistic spin-THz field coupling
locally breaks the inversion symmetry, resulting in the formation of odd
sidebands which otherwise are absent.

</DOC>
<DOC>
<DOCNO> 121831 </DOCNO>
Kinematics of Molecular Hydrogen Emission from Pre-planetary Nebulae:


  We present high spectral resolution maps of near-infrared molecular hydrogen
emission from the bipolar pre-planetary nebulae RAFGL 2688 and RAFGL 618,
obtained with the NOAO Phoenix spectrometer. The measured velocity gradients
along the polar axes of both nebulae indicate that the highest velocity gas
lies closest to the central stars. These results support the suggestion that
the polar H_2 emission regions of both nebulae contain shocked gas formed as
fast (~50-150 km/s), collimated, post-asymptotic giant branch (AGB) winds
collide with slower-moving (~10-20 km/s) material previously ejected while the
central stars were still on the AGB. The kinematics of H_2 emission
perpendicular to the polar axis of RAFGL 2688 are consistent with a model
combining expansion along the equator at 5-10 km/s with rotation about the
polar axis at 5-10 km/s. The rapid onset of the common envelope phase of a
close binary system may explain both the bipolar structure of RAFGL 2688 and
the presence and complex kinematics of its shocked H_2 emission.

</DOC>
<DOC>
<DOCNO> 9018 </DOCNO>
d-wave superconductivity and Pomeranchuk instability in the


  We present a systematic stability analysis for the two-dimensional Hubbard
model, which is based on a new renormalization group method for interacting
Fermi systems. The flow of effective interactions and susceptibilities confirms
the expected existence of a d-wave pairing instability driven by
antiferromagnetic spin fluctuations. More unexpectedly, we find that strong
forward scattering interactions develop which may lead to a Pomeranchuk
instability breaking the tetragonal symmetry of the Fermi surface.

</DOC>
<DOC>
<DOCNO> 9270 </DOCNO>
Renormalization Group, hidden symmetries and approximate Ward identities


  An expansion based on renormalization group methods for the spin correlation
function in the z direction of the Heisenberg-Ising XYZ chain with an external
magnetic field directed as the z axis is derived. Moreover, by using the hidden
symmetries of the model, we show that the running coupling constants are small,
if the coupling in the z direction is small enough, that a critical index
appearing in the correlation function is exactly vanishing (because of an
approximate Ward identity) and other properties, so obtaining a rather detailed
description of the XYZ correlation function.

</DOC>
<DOC>
<DOCNO> 67700 </DOCNO>
Masses of the Goldstone modes in the CFL phase of QCD at finite density


  We construct the U_L(3) x U_R(3) effective lagrangian which encodes the
dynamics of the low energy pseudoscalar excitations in the Color-Flavor-Locking
superconducting phase of QCD at finite quark density. We include the effects of
instanton-induced interactions and study the mass pattern of the pseudoscalar
mesons. A tentative comparison with the analytical estimate for the gap
suggests that some of these low energy momentum modes are not stable for
moderate values of the quark chemical potential.

</DOC>
<DOC>
<DOCNO> 117056 </DOCNO>
On the sensitivity of wave channeling of X-ray beam to the shape of


  The effect of transmission of x-ray beams through submicron capillaries was
investigated with account for diffraction and roughness scattering. Possible
explanation of anomalous energy dependence of transmission through thin Cr/C/Cr
channeles was given due to effect of periodic deformations.

</DOC>
<DOC>
<DOCNO> 7994 </DOCNO>
Time correlations of a laser-induced Bose-Einstein condensate


  We analyze the multi-time correlations of a laser-induced Bose-Einstein
condensate. We use quantum stochastic methods to obtain under certain
circumstances a Fokker-Planck equation which describes the phase-difussion
process, and obtain an analytical expression of the two-time correlations. We
perform also quantum Monte Carlo numerical simulations of the correlations,
which are in good agreement with the predicted analytical results.

</DOC>
<DOC>
<DOCNO> 100883 </DOCNO>
Representable E-theory for Co(X)-algebras


  Let X be a locally compact space, and let A and B be Co(X)-algebras. We
define the notion of an asymptotic Co(X)-morphism from A to B and construct
representable E-theory groups RE(X;A,B). These are the universal groups on the
category of separable Co(X)-algebras that are Co(X)-stable,
Co(X)-homotopy-invariant, and half-exact. If A is RKK(X)-nuclear, these groups
are naturally isomorphic to Kasparov's representable KK-theory groups
RKK(X;A,B). Applications and examples are also discussed.

</DOC>
<DOC>
<DOCNO> 120999 </DOCNO>
X-ray Emission from Isolated Be Stars


  I discuss the X-ray observations of Be stars, and how their properties
compare to non-emission B stars. I focus on several specific stars that show
high flux levels and variability but also report on several interesting survey
results. The Be X-ray properties are discussed in the context of wind-shock
X-ray emission from normal OB stars as well as in the context of general
mechanisms that have been proposed to explain the Be phenomenon. Finally, I
conclude with a discussion of the spectral diagnostics that will be available
from the new generation of X-ray telescopes.

</DOC>
<DOC>
<DOCNO> 100143 </DOCNO>
On unentangled Gleason theorems for quantum information theory


  It is shown here that a strengthening of Wallach's Unentangled Gleason
Theorem can be obtained by applying results of the present authors on
generalised Gleason theorems for quantum multi-measures arising from
investigations of quantum decoherence functionals.

</DOC>
<DOC>
<DOCNO> 118139 </DOCNO>
Thomson Thick X-ray Absorption in a Broad Absorption Line Quasar


  We present a deep ASCA observation of a Broad
 Absorption Line Quasar (BALQSO) PG0946+301. The source was clearly detected in
one of the gas imaging spectrometers, but not in any other detector. If BALQSOs
have intrinsic X-ray spectra similar to normal radio-quiet quasars, our
observations imply that there is Thomson thick X-ray absorption (N_H >~10^{24}
cm^{-2}) toward
 PG0946+301. This is the largest column density estimated so far toward a
BALQSO. The absorber must be at least partially ionized and may be responsible
for attenuation in the optical and UV. If the
 Thomson optical depth toward BALQSOs is close to one, as inferred here, then
spectroscopy in hard X-rays with large telescopes like XMM would be feasible.

</DOC>
<DOC>
<DOCNO> 83443 </DOCNO>
A Novelty-based Evaluation Method for Information Retrieval


  In information retrieval research, precision and recall have long been used
to evaluate IR systems. However, given that a number of retrieval systems
resembling one another are already available to the public, it is valuable to
retrieve novel relevant documents, i.e., documents that cannot be retrieved by
those existing systems. In view of this problem, we propose an evaluation
method that favors systems retrieving as many novel documents as possible. We
also used our method to evaluate systems that participated in the IREX
workshop.

</DOC>
<DOC>
<DOCNO> 121729 </DOCNO>
Spiral and irregular galaxies in the Hubble Deep Field North -


  We analyze a morphologically-selected complete sample of 52 late-type (spiral
and irregular) galaxies in the Hubble Deep Field North with total K-magnitudes
brighter than K=20.47. This sample exploits in particular the ultimate imaging
quality achieved by HST in this field, allowing us to clearly disentangle the
galaxy morphologies, based on accurate profiles of the surface brightness
distributions. Our purpose was to investigate systematic differences between
the two classes, as for colours, redshift distributions and ages of the
dominant stellar populations. This sample appears to miss significantly
galaxies above z=1.4 (in a similar way as an early-type galaxy sample
previously studied by us), a fact which may be explained as a global decline of
the underlying mass function for galaxies at these high redshifts. Differences
between early and late-types are apparent -particularly in the colour
distributions and the evolutionary star-formation (SF) rates per unit volume-,
although the complication in spectro-photometric modelling introduced by
dust-extinction in the gas-rich systems prevents us to reach conclusive results
on the single sources. However, we find that an integrated quantity like the
comoving star-formation rate density (SFR(t)) as a function of redshift is much
less affected by these uncertainties: by combining this with the previously
studied early-type galaxy sample, we find a shallower dependence of SFR(t) on z
between z=0.2 and z=1.5 than found by Lilly et al. (1995).

</DOC>
<DOC>
<DOCNO> 150373 </DOCNO>
Conformal Anomaly and Large Scale Gravitational Coupling


  We present a model in which the breackdown of conformal symmetry of a quantum
stress-tensor due to the trace anomaly is related to a cosmological effect in a
gravitational model. This is done by characterizing the traceless part of the
quantum stress-tensor in terms of the stress-tensor of a conformal invariant
classical scalar field. We introduce a conformal frame in which the anomalous
trace is identified with a cosmological constant. In this conformal frame we
establish the Einstein field equations by connecting the quantum stress-tensor
with the large scale distribution of matter in the universe.

</DOC>
<DOC>
<DOCNO> 84933 </DOCNO>
Generalized Equivalence Principle in Extended New General Relativity


  In extended new general relativity, which is formulated as a reduction of
$\bar{Poincar\'e} $gauge theory of gravity whose gauge group is the covering
group of the Poincar\'e group, we study the problem of whether the total
energy-momentum, total angular momentum and total charge are equal to the
corresponding quantities of the gravitational source. We examine this for
charged axi-symmetric solutions of gravitational field equations. Our main
concern is the restriction on the asymptotic form of the gravitational field
variables imposed by the requirement that physical quantities of the total
system are equivalent to the corresponding quantities of the charged rotating
source body. This requirement can be regarded as an equivalence principle in a
generalized sense.

</DOC>
<DOC>
<DOCNO> 119964 </DOCNO>
Reconstructing the evolution of double helium white dwarfs: envelope


  The unique core-mass - radius relation for giants with degenerate helium
cores enables us to reconstruct the evolution of three observed double helium
white dwarfs with known masses of both components.
  The last mass transfer phase in their evolution must have been a spiral-in.
In the formalism proposed by Webbink (1984), we can constrain the efficiency of
the deposition of orbital energy into the envelope to be $1 \la \alpha \la 6$,
for an envelope structure parameter $\lambda=0.5$. We find that the two
standard mass transfer types (stable mass transfer and spiral-in) are both
unable to explain the first phase of mass transfer for these three binaries.
  We use a parametric approach to describe mass transfer in low-mass binaries,
where both stars are of comparable mass and find that the orbital
characteristics of the observed double helium white dwarfs can be well
reproduced if the envelope of the primary is lost with ~1.5 times the specific
angular momentum of the initial binary. In this case no substantial spiral-in
occurs.

</DOC>
<DOC>
<DOCNO> 116553 </DOCNO>
Polarization dependence of four-wave mixing in a degenerate two-level


  Nearly degenerate four-wave mixing (NDFWM) within a closed degenerate
two-level atomic transition is theoretically and experimentally examined. Using
the model presented by A. Lezama et al [Phys. Rev. A 61, 013801 (2000)] the
NDFWM spectra corresponding to different pump and probe polarization cases are
calculated and discussed. The calculated spectra are compared to the
observation of NDFWM within the $6S_{1/2}(F=4)\to 6P_{3/2}(F=5)$ transition of
cesium in a phase conjugation experiment using magneto optically cooled atoms

</DOC>
<DOC>
<DOCNO> 102683 </DOCNO>
Does the Jones polynomial detect the unknot?


  We address the question: Does there exist a non-trivial knot with a trivial
Jones polynomial? To find such a knot, it is almost certainly sufficient to
find a non-trivial braid on four strands in the kernel of the Burau
representation. I will describe a computer algorithm to search for such a
braid.

</DOC>
<DOC>
<DOCNO> 83498 </DOCNO>
The Role of Commutativity in Constraint Propagation Algorithms


  Constraint propagation algorithms form an important part of most of the
constraint programming systems. We provide here a simple, yet very general
framework that allows us to explain several constraint propagation algorithms
in a systematic way. In this framework we proceed in two steps. First, we
introduce a generic iteration algorithm on partial orderings and prove its
correctness in an abstract setting. Then we instantiate this algorithm with
specific partial orderings and functions to obtain specific constraint
propagation algorithms.
  In particular, using the notions commutativity and semi-commutativity, we
show that the {\tt AC-3}, {\tt PC-2}, {\tt DAC} and {\tt DPC} algorithms for
achieving (directional) arc consistency and (directional) path consistency are
instances of a single generic algorithm. The work reported here extends and
simplifies that of Apt \citeyear{Apt99b}.

</DOC>
<DOC>
<DOCNO> 71222 </DOCNO>
String Fluctuations, AdS/CFT and the Soft Pomeron Intercept


  We study high energy scattering amplitudes in a strongly coupled (confining)
gauge theory using the AdS/CFT correspondence. The scattering described by a
Wilson line/loop correlation function was shown earlier to correspond to
minimal surfaces of the helicoid type, and gave amplitudes with unit intercept
and linear trajectory. In this paper we find the correction to the intercept
from quadratic fluctuations of the string worldsheet around the helicoid. The
relevant term comes from analytical continuation of a L\"uscher like term. It
is coupling-constant independent and proportional to the number of effective
transverse flat dimensions. The shift of the intercept, under our assumptions,
is $n_\perp /96$, and for $n_\perp=7,8$ gives respectively 0.0729, 0.083.
Incidentally we note that this is surprisingly close to the observed value of
0.08.

</DOC>
<DOC>
<DOCNO> 68087 </DOCNO>
A new approach to the parametrization of the Cabibbo-Kobayashi-Maskawa


  The CKM-matrix V is written as a linear combination of the unit matrix I and
a matrix U which causes intergenerational-mixing. It is shown that such a V
results from a class of quark-mass matrices. The matrix U has to be hermitian
and unitary and therefore can depend at most on 4 real parameters. The
available data on the CKM-matrix including CP-violation can be reproduced by
$V=(I+iU)/\sqrt{2}$. This is also true for the special case when U depends on
\textit{only 2 real parameters}. There is no CP-violating phase in this
parametrization. Also, for such a V the invariant phase $\Phi \equiv \phi
_{12}+\phi_{23}-\phi_{13}$, satisfies a criterion suggested for `maximal'
CP-violation.

</DOC>
<DOC>
<DOCNO> 101874 </DOCNO>
Global regularity of wave maps I. Small critical Sobolev norm in high


  We show that wave maps from Minkowski space $R^{1+n}$ to a sphere are
globally smooth if the initial data is smooth and has small norm in the
critical Sobolev space $\dot H^{n/2}$ in the high dimensional case $n \geq 5$.
A major difficulty, not present in the earlier results, is that the $\dot
H^{n/2}$ norm barely fails to control $L^\infty$, potentially causing a
logarithmic divergence in the nonlinearity; however, this can be overcome by
using co-ordinate frames adapted to the wave map by approximate parallel
transport. In the sequel of this paper we address the more interesting
two-dimensional case, which is energy-critical.

</DOC>
<DOC>
<DOCNO> 10586 </DOCNO>
Some Fundamental Properties of the Integer-States in Open-System,


  Ensemble averages are an approximation technique for connecting macroscopic
and microscopic properties of a system. For systems open with respect to
exchange of particles with a bath, the microscopic states are those with
integer numbers of particles. When a property of the open system is represented
as an ensemble average over these microscopic states, self-consistency dictates
several implications for the properties of both for open-system energy density
functionals and the integer-state functionals describing the microscopic
states. The first is that each integer-state energy density functional is a
functional of the original type discovered by Levy. Another is that the
dependence of the open-system functional on the ensemble density is linear
whereas the dependence of the integer-state functional is decidedly nonlinear.
Finally, the derivative discontinuity behavior with respect to particle number
of some open-system density functionals appears to be connected to the
long-range behavior of the effective external potentials of the integer-state
functionals governing the interactions among subsystems in the ensemble.

</DOC>
<DOC>
<DOCNO> 100109 </DOCNO>
On the Landau-Ginzburg description of Boundary CFTs and special


  We consider Landau-Ginzburg (LG) models with boundary conditions preserving
A-type N=2 supersymmetry. We show the equivalence of a linear class of boundary
conditions in the LG model to a particular class of boundary states in the
corresponding CFT by an explicit computation of the open-string Witten index in
the LG model. We extend the linear class of boundary conditions to general
non-linear boundary conditions and determine their consistency with A-type N=2
supersymmetry. This enables us to provide a microscopic description of special
Lagrangian submanifolds in C^n due to Harvey and Lawson. We generalise this
construction to the case of hypersurfaces in P^n. We find that the boundary
conditions must necessarily have vanishing Poisson bracket with the combination
(W(\phi)-\bar{W}(\bar{\phi})), where W(\phi) is the appropriate superpotential
for the hypersurface. An interesting application considered is the T^3
supersymmetric cycle of the quintic in the large complex structure limit.

</DOC>
<DOC>
<DOCNO> 118260 </DOCNO>
Cluster Selection and the Evolution of Brightest Cluster Galaxies


  The K-band Hubble diagram of Brightest Cluster Galaxies (BCGs) is presented
for a large, X-ray selected cluster sample extending out to z = 0.8. The
controversy over the degree of BCG evolution is shown to be due to sample
selection, since the BCG luminosity depends upon the cluster environment.
Selecting only the most X-ray luminous clusters produces a BCG sample which
shows, under the assumption of an Einstein-de Sitter cosmology, significantly
less mass growth than that predicted by current semi-analytic galaxy formation
models, and significant evidence of any growth only if the dominant stellar
population of the BCGs formed relatively recently (z <= 2.6).

</DOC>
<DOC>
<DOCNO> 71021 </DOCNO>
Strangelets at Chacaltaya


  We discuss the possible imprints of strangelets (i.e., lumps of Strange Quark
Matter) in Chacaltaya experimental data using model of propagation of such
objects through the atmosphere developed by us recently.

</DOC>
<DOC>
<DOCNO> 85097 </DOCNO>
TASI lectures on black holes in string theory


  This is a write-up of introductory lectures on black holes in string theory
given at TASI-99. Topics discussed include: Black holes, thermodynamics and the
Bekenstein-Hawking entropy, the information problem; supergravity actions,
conserved quantum numbers, supersymmetry and BPS states, units and duality,
dimensional reduction, solution-generating; extremal M-branes and D-branes,
smearing, probe actions, nonextremal branes, the Gregory-Laflamme instability;
breakdown of supergravity and the Correspondence Principle, limits in parameter
space, singularity resolution; making black holes with branes,
intersection-ology, explicit d=5,4 examples; string/brane computations of
extremal black hole entropy in d=5,4, rotation, fractionation; non-extremality
and entropy, the link to BTZ black holes, Hawking radiation and absorption
cross-sections in the string/brane and supergravity pictures.

</DOC>
<DOC>
<DOCNO> 99974 </DOCNO>
Foliation groupoids and their cyclic homology


  In this paper we study the Lie groupoids which appear in foliation theory. A
foliation groupoid is a Lie groupoid which integrates a foliation, or,
equivalently, whose anchor map is injective. The first theorem shows that, for
a Lie groupoid G, the following are equivalent:
  - G is a foliation groupoid,
  - G has discrete isotropy groups,
  - G is Morita equivalent to an etale groupoid.
  Moreover, we show that among the Lie groupoids integrating a given foliation,
the holonomy and the monodromy groupoids are extreme examples.
  The second theorem shows that the cyclic homology of convolution algebras of
foliation groupoids is invariant under Morita equivalence of groupoids, and we
give explicit formulas. Combined with the previous results of Brylinski, Nistor
and the authors, this theorem completes the computation of cyclic homology for
various foliation groupoids, like the (full) holonomy/monodromy groupoid, Lie
groupoids modeling orbifolds, and crossed products by actions of Lie groups
with finite stabilizers. Some parts of the proof, such as the H-unitality of
convolution algebras, apply to general Lie groupoids.
  Since one of our motivation is a better understanding of various approaches
to longitudinal index theorems for foliations, we have added a few brief
comments at the end of the second section.

</DOC>
<DOC>
<DOCNO> 40085 </DOCNO>
Search for Trilinear Neutral Gauge Boson Couplings in Z-gamma production


  The data recorded at a centre-of-mass energy of 189GeV by the OPAL detector
at LEP are used to search for trilinear couplings of the neutral gauge bosons
in the process e+e- --> Z-gamma. The cross-sections are measured for
multihadronic events with an energetic isolated photon and for events with a
high energy photon accompanied by missing energy. These cross-sections and the
photon energy, polar angle and isolation angle distributions are compared to
the Standard Model predictions and to the theoretical expectations of a model
allowing for Z-gamma-Z and Z-gamma-gamma vertices. Since no significant
deviations with respect to the Standard Model expectations are found,
constraints are derived on the strength of neutral trilinear gauge couplings.

</DOC>
<DOC>
<DOCNO> 70802 </DOCNO>
On a fate of hot quantum field theories


  It is argued that for hot quantum fields, the necessary effective
perturbation theories may be based on a resummation procedure which, contrarily
to the zero temperature case, differs substantially from the one ordinarily in
use. Important differences show up in the infrared sector of hot quantum field
theories.

</DOC>
<DOC>
<DOCNO> 12372 </DOCNO>
Establishment of a stable vortex state in the peak effect region in a


  We present magnetization data on a weakly pinned CeRu_2 single crystal
showing the existence of a stable state of the vortex lattice in the peak
effect region. The stable state is achieved by cycling the magnetic field by
small amplitude. This stable state is characterized by a unique value of
critical current density (J_c), independent of the magnetic history of the
sample. The results support the recent model proposed by Ravikumar et al
\cite{r39} on the history dependence of the J_c.

</DOC>
<DOC>
<DOCNO> 100282 </DOCNO>
ad-nilpotent $\frak b$-ideals in sl(n) having a fixed class of


  We study the combinatorics of ad-nilpotent ideals of a Borel subalgebra of
$sl(n+1,\Bbb C)$. We provide an inductive method for calculating the class of
nilpotence of these ideals and formulas for the number of ideals having a given
class of nilpotence. We study the relationships between these results and the
combinatorics of Dyck paths, based upon a remarkable bijection between
ad-nilpotent ideals and Dyck paths. Finally, we propose a (q,t)-analogue of the
Catalan number $C_n$. These (q,t)-Catalan numbers count on the one hand
ad-nilpotent ideals with respect to dimension and class of nilpotence, and on
the other hand admit interpretations in terms of natural statistics on Dyck
paths.

</DOC>
<DOC>
<DOCNO> 123065 </DOCNO>
Leonid Electrophonic Bursters


  We investigate the conditions under which Leonid meteoroids might generate
short duration (burster) electrophonic sounds. A `first order' theory is
employed to estimate the approximate electron number density in the meteoroid
ablation column as a function of time. Using the threshold conditions discussed
in an earlier communication (Beech and Foschini 1999) we find that Leonid
meteoroids more massive than about 0.1 kg can potentially generate short
duration electrophonic bursters.

</DOC>
<DOC>
<DOCNO> 100529 </DOCNO>
Stieltjes integrals of H\"older continuous functions with applications


  We give a new estimate on Stieltjes integrals of H\"older continuous
functions and use it to prove an existence-uniqueness theorem for solutions of
ordinary differential equations with H\"older continuous forcing. We construct
stochastic integrals with respect to fractional Brownian motion, and establish
sufficient conditions for its existence. We prove that stochastic differential
equations with fractional Brownian motion have a unique solution with
probability 1 in certain classes of H\"older-continuous functions. We give tail
estimates of the maximum of stochastic integrals from tail estimates of the
H\"older coefficient of fractional Brownian motion. In addition we apply the
techniques used for ordinary Brownian motion to construct stochastic integrals
of deterministic functions with respect to fractional Brownian motion and give
tail estimates of its maximum.

</DOC>
<DOC>
<DOCNO> 8146 </DOCNO>
Spin Glass Ordering in Diluted Magnetic Semiconductors: a Monte Carlo


  We study the temperature-dilution phase diagram of a site-diluted Heisenberg
antiferromagnet on a fcc lattice, with and without the Dzyaloshinskii-Moriya
anisotropic term, fixed to realistic microscopic parameters for $IIB_{1-x} Mn_x
Te$ (IIB=Cd, Hg, Zn). We show that the dipolar Dzyaloshinskii-Moriya anisotropy
induces a finite-temperature phase transition to a spin glass phase, at
dilutions larger than 80%. The resulting probability distribution of the order
parameter P(q) is similar to the one found in the cubic lattice
Edwards-Anderson Ising model. The critical exponents undergo large finite size
corrections, but tend to values similar to the ones of the
Edwards-Anderson-Ising model.

</DOC>
<DOC>
<DOCNO> 178999 </DOCNO>
Effects of nuclear re-interactions in quasi-elastic neutrino-nucleus


  The effects of nuclear re-interactions in the quasi-elastic neutrino-nucleus
scattering are investigated with a phenomenological model. We found that the
nuclear responses are lowered and their maxima are shifted towards higher
excitation energies. This is reflected on the total neutrino-nucleus cross
section in a general reduction of about 15% for neutrino energies above 300
MeV.

</DOC>
<DOC>
<DOCNO> 84308 </DOCNO>
Inflation and quintessence with nonminimal coupling


  The nonminimal coupling (NMC) of the scalar field to the Ricci curvature is
unavoidable in many cosmological scenarios. Inflation and quintessence models
based on nonminimally coupled scalar fields are studied, with particular
attention to the balance between the scalar potential and the NMC term in the
action. NMC makes acceleration of the universe harder to achieve for the usual
potentials, but it is beneficial in obtaining cosmic acceleration with unusual
potentials. The slow-roll approximation with NMC, conformal transformation
techniques, and other aspects of the physics of NMC are clarified.

</DOC>
<DOC>
<DOCNO> 102073 </DOCNO>
Families of (1,2)-Symplectic M etrics on Full Flag Manifolds


  We obtain new families of (1,2)-symplectic invariant metrics on the full
complex flag manifolds F(n). For n > 4, we characterize n-3 different
n-dimensional families of (1,2)-symplectic invariant metrics on F(n). Any of
these families corresponds to a different class of non-integrable invariant
almost complex structure on F(n).

</DOC>
<DOC>
<DOCNO> 120608 </DOCNO>
Spatial Variability in the Ratio of Interstellar Atomic Deuterium to


  To measure interstellar atomic deuterium abundances, we used the Interstellar
Medium Absorption Profile Spectrograph (IMAPS) to obtain spectra of gamma2 Vel
and zeta Pup over the wavelength interval 930-1150 A at a resolving power of
80,000. The interstellar D I features are resolved and cleanly separated from
interstellar H I in the Ly-delta and Ly-epsilon profiles of both sight lines,
and also in the Ly-gamma profile of zeta Pup. The D I profiles were modeled
using a velocity template derived from several N I lines in the IMAPS spectra
recorded at higher S/N. To find the best D I column density, we minimized
chi-squares for model D I profiles that included not only the N(D I) as a free
parameter, but also the effects of several potential sources of systematic
error which could also be varied. For both stars, H I column densities were
measured by analyzing Ly-alpha absorption profiles in a large number of IUE
high dispersion spectra. Ultimately we found that D/H = 2.18(+0.36,-0.31)e-5
for gamma2 Vel and 1.42(+0.25,-0.23)e-5 for zeta Pup, values that contrast
markedly with D/H derived in Paper I for delta Ori (the stated errors are 90%
confidence limits). Evidently, the atomic D/H ratio in the ISM, averaged over
path lengths of 250 to 500 pc, exhibits significant spatial variability.
Furthermore, variations in D/H do not appear to be anticorrelated with N/H.
Within the framework of standard Big Bang Nucleosynthesis, the large value of
D/H found toward gamma2 Vel is equivalent to a cosmic baryon density of Omega_B
h^2 = 0.023 (+-0.002), which we regard as an upper limit since there is no
correction for the destruction of deuterium in stars.

</DOC>
<DOC>
<DOCNO> 118566 </DOCNO>
The European Large Area ISO Survey II: mid-infrared extragalactic source


  We present preliminary source counts at 6.7um and 15um from the Preliminary
Analysis of the European Large Area ISO survey, with limiting flux densities of
\~2mJy at 15um & ~1mJy at 6.7um. We separate the stellar contribution from the
extragalactic using identifications with APM sources made with the likelihood
ratio technique. We quantify the completeness & reliability of our source
extraction using (a) repeated observations over small areas, (b) cross-IDs with
stars of known spectral type, (c) detections of the PSF wings around bright
sources, (d) comparison with independent algorithms. Flux calibration at 15um
was performed using stellar IDs; the calibration does not agree with the
pre-flight estimates, probably due to effects of detector hysteresis and
photometric aperture correction. The 6.7um extragalactic counts are broadly
reproduced in the Pearson & Rowan-Robinson model, but the Franceschini et al.
(1997) model underpredicts the observed source density by ~0.5-1 dex, though
the photometry at 6.7um is still preliminary. At 15um the extragalactic counts
are in excellent agreement with the predictions of the Pearson & Rowan-Robinson
(1996), Franceschini et al. (1994), Guiderdoni et al. (1997) and the evolving
models of Xu et al. (1998), over 7 orders of magnitude in 15um flux density.
The counts agree with other estimates from the ISOCAM instrument at overlapping
flux densities (Elbaz et al. 1999), provided a consistent flux calibration is
used. Luminosity evolution at a rate of (1+z)^3, incorporating mid-IR spectral
features, provides a better fit to the 15um differential counts than (1+z)^4
density evolution. No-evolution models are excluded, and implying that below
around 10mJy at 15um the source counts become dominated by an evolving
cosmological population of dust-shrouded starbursts and/or active galaxies.

</DOC>
<DOC>
<DOCNO> 99576 </DOCNO>
Fuglede's conjecture for a union of two intervals


  We prove that a union of two intervals in R is a spectral set if and only if
it tiles R by translations.

</DOC>
<DOC>
<DOCNO> 71142 </DOCNO>
Nucleon Polarizabilities


  The subject of nucleon polarizabilities in real, virtual, and doubly virtual
Compton scattering is discussed with respect to what is known and how such
quantities can be extracted from data.

</DOC>
<DOC>
<DOCNO> 100050 </DOCNO>
Standard conjectures for the arithmetic Grassmannian G(2,N) and Racah


  We prove the arithmetic Hodge index and hard Lefschetz conjectures for the
Grassmannian $G=G(2,N)$ parametrizing lines in projective space, for the
natural arithmetic Lefschetz operator defined via the Pl\"ucker embedding of
$G$ in projective space. The analysis of the Hodge index inequalities involves
estimates on certain Racah polynomials.

</DOC>
<DOC>
<DOCNO> 9945 </DOCNO>
Experimental evidences of Luttinger liquid behavior in the crossed


  Luttinger liquid behavior was observed in a crossed junction formed with two
metallic multi-wall carbon nanotubes whose differential conductance vanished
with the power of bias voltage and temperature. With applying constant voltage
or current to one of the two carbon nanotubes in a crossed geometry, the
electrical transport properties of the other carbon nanotube were affected
significantly, implying there exists strong correlation between the carbon
nanotubes. Such characteristic features are in good agreement with the
theoretical predictions for the crossed two Luttinger liquids.

</DOC>
<DOC>
<DOCNO> 150325 </DOCNO>
A geometric discretisation scheme applied to the Abelian Chern-Simons


  We give a detailed general description of a recent geometrical discretisation
scheme and illustrate, by explicit numerical calculation, the scheme's ability
to capture topological features. The scheme is applied to the Abelian
Chern-Simons theory and leads, after a necessary field doubling, to an
expression for the discrete partition function in terms of untwisted
Reidemeister torsion and of various triangulation dependent factors. The
discrete partition function is evaluated computationally for various
triangulations of $S^3$ and of lens spaces. The results confirm that the
discretisation scheme is triangulation independent and coincides with the
continuum partition function

</DOC>
<DOC>
<DOCNO> 9346 </DOCNO>
Scattering of elastic waves by periodic arrays of spherical bodies


  We develop a formalism for the calculation of the frequency band structure of
a phononic crystal consisting of non-overlapping elastic spheres, characterized
by Lam\'e coefficients which may be complex and frequency dependent, arranged
periodically in a host medium with different mass density and Lam\'e
coefficients. We view the crystal as a sequence of planes of spheres, parallel
to and having the two dimensional periodicity of a given crystallographic
plane, and obtain the complex band structure of the infinite crystal associated
with this plane. The method allows one to calculate, also, the transmission,
reflection, and absorption coefficients for an elastic wave (longitudinal or
transverse) incident, at any angle, on a slab of the crystal of finite
thickness. We demonstrate the efficiency of the method by applying it to a
specific example.

</DOC>
<DOC>
<DOCNO> 72194 </DOCNO>
$\etap K$ puzzle of B meson decays and new physics effects in the


  we calculate the new physics contributions to seven measured decays $B \to
\pi^+ \pi^-, K \pi$ and $ K \etap$ in the general two-Higgs-doublet model
(Model III). Within the considered parameter space, we find that: (a) the
CLEO/BaBar measurement of $B\to \pi^+ \pi^-$ decay prefers a small
$F_0^{B\pi}(0)$: $F_0^{B\pi}(0)=0.25 \pm 0.03$; (b) the new physics
enhancements to the penguin-dominated $B \to K\pi$ and $B\to K \etap$ decays
are significant in size, $\sim (40-70)%$ $w.r.t$ the standard model
predictions; and (c) the new physics enhancements can boost the branching
ratios ${\cal B}(B \to K^+ \etap)$ and ${\cal B}(B \to K^0 \etap)$ to be
consistent with the data within one standard deviation, and hence lead to a
simple and plausible new physics interpretation for the $\etap K$ puzzle.

</DOC>
<DOC>
<DOCNO> 120147 </DOCNO>
Exploring Halo Substructure with Giant Stars: I. Survey Description and


  We have begun a survey of the structure of the Milky Way halo, as well as the
halos of other Local Group galaxies, as traced by their constituent giant
stars. These giant stars are identified via large area, CCD photometric
campaigns. Here we present the basis for our photometric search method, which
relies on the gravity sensitivity of the Mg I triplet + MgH features near 5150
Angstroms in F-K stars, and which is sensed by the flux in the intermediate
band DDO51 filter. To calibrate our (M-T_2, M-DDO51) diagram as a means to
discriminate field giant stars from nearby dwarfs, we utilize new photometry of
the main sequences of the open clusters NGC 3680 and NGC 2477 and the red giant
branches of the clusters NGC 3680, Melotte 66 and omega Centauri, supplemented
with data on field stars, globular clusters and open clusters by Doug Geisler
and collaborators. By combining the data on stars from different clusters, and
by taking advantage of the wide abundance spread within omega Centauri, we
verify the primary dependence of the M-DDO51 color on luminosity, and
demonstrate the secondary sensitivity to metallicity among giant stars. Our
empirical results are found to be generally consistent with those from analysis
of synthetic spectra by Paltoglou & Bell [1994, MNRAS, 268, 793].

</DOC>
<DOC>
<DOCNO> 9866 </DOCNO>
Synchronization, Diversity, and Topology of Networks of Integrate and


  We study synchronization dynamics of a population of pulse-coupled
oscillators. In particular, we focus our attention in the interplay between
networks topological disorder and its synchronization features. Firstly, we
analyze synchronization time $T$ in random networks, and find a scaling law
which relates $T$ to networks connectivity. Then, we carry on comparing
synchronization time for several other topological configurations,
characterized by a different degree of randomness. The analysis shows that
regular lattices perform better than any other disordered network. The fact can
be understood by considering the variability in the number of links between two
adjacent neighbors. This phenomenon is equivalent to have a non-random topology
with a distribution of interactions and it can be removed by an adequate local
normalization of the couplings.

</DOC>
<DOC>
<DOCNO> 10535 </DOCNO>
The excitation spectrum of mesoscopic proximity structures


  We investigate one aspect of the proximity effect, viz., the local density of
states of a superconductor-normal metal sandwich. In contrast to earlier work,
we allow for the presence of an arbitrary concentration of impurities in the
structure. The superconductor induces a gap in the normal metal spectrum that
is proportional to the inverse of the elastic mean free path l_N for rather
clean systems. For a mean free path much shorter than the thickness of the
normal metal, we find a gap size proportional to l_N that approaches the
behavior predicted by the Usadel equation (diffusive limit). We also discuss
the influence of interface and surface roughness, the consequences of a
non-ideal transmittivity of the interface, and the dependence of our results on
the choice of the model of impurity scattering.

</DOC>
<DOC>
<DOCNO> 170063 </DOCNO>
Perturbative evolution of far off-resonance driven two-level systems:


  The time evolution of driven two-level systems in the far off-resonance
regime is studied analytically. We obtain a general first-order perturbative
expression for the time-dependent density operator which is applicable
regardless of the coupling strength value. In the strong field regime, our
perturbative expansion remains valid even when the far off-resonance condition
is not fulfilled. We find that, in the absence of dissipation, driven two-level
systems exhibit coherent population trapping in a certain region of parameter
space, a property which, in the particular case of a symmetric double-well
potential, implies the well-known localization of the system in one of the two
wells. Finally, we show how the high-order harmonic generation that this kind
of systems display can be obtained as a straightforward application of our
formulation.

</DOC>
<DOC>
<DOCNO> 12894 </DOCNO>
Magnetic storage device with improved temporal stability


  The current efforts to fabricate non-volatile magnetic recording media with a
high areal density is deteriorated by the increasing temporal instability of
the stored information. If the stored energy per magnetic particle competes
with the thermal energy, spontaneous magnetic reversal processes may occur.
Deposition of the magnetic particles on top of an antiferromagnetic substrate
will increase its energy barrier due to the exchange coupling between the two
subsystems. For this the magnetic moments of the antiferromagnet in the
vicinity of the magnetic particle have to deviate from their undisturbed
arrangement. This disturbation vanishes within a few lattice constants. In the
framework of a classical spin model we calculate the spin arrangements and the
resulting energy barriers for typical systems.

</DOC>
<DOC>
<DOCNO> 116671 </DOCNO>
Charging kinetics of dust particles with a variable mass


  A kinetic equation for dust particles with a new kinetic variable - the mass
of grains - is suggested for the description of processes with changing mass in
dusty plasmas and neutral systems.

</DOC>
<DOC>
<DOCNO> 100043 </DOCNO>
Limits of Weierstrass points in regular smoothings of curves with two


  In the 80's D. Eisenbud and J. Harris posed the following question: "What are
the limits of Weierstrass points in families of curves degenerating to stable
curves not of compact type?" We answer their question for one-dimensional
families of smooth curves degenerating to stable curves with just two
components meeting at points in general position. In this note we treat only
those families whose total space is regular. Nevertheless, we announce here our
most general answer, to be presented in detail in a forthcoming submission.

</DOC>
<DOC>
<DOCNO> 13237 </DOCNO>
The Specific Heat of Normal, Degenerate Quark Matter: Non-Fermi Liquid


  In normal degenerate quark matter, the exchange of dynamically screened
transverse gluons introduces infrared divergences in the quark self-energies
that lead to the breakdown of the Fermi liquid description. If the core of
neutron stars are composed of quark matter with a normal component, cooling by
direct quark Urca processes may be modified by non-Fermi liquid corrections. We
find that while the quasiparticle density of states is finite and non-zero at
the Fermi surface, its frequency derivative diverges and results in non-Fermi
liquid corrections to the specific heat of the normal, degenerate component of
quark matter. We study these non-perturbative non-Fermi liquid corrections to
the specific heat and the temperature dependence of the chemical potential and
show that these lead to a reduction of the specific heat.

</DOC>
<DOC>
<DOCNO> 68416 </DOCNO>
Top quark, heavy fermions and the composite Higgs boson


  We study the properties of heavy fermions in the vector-like representation
of the electro-weak gauge group $SU(2)_W\times U(1)_Y$ with Yukawa couplings to
the standard model Higgs boson. Applying the renormalization group analysis, we
discuss the effects of heavy fermions to the vacuum stability bound and the
triviality bound on the mass of the Higgs boson. We also discuss the
interesting possibility that the Higgs particle is composed of the top quark
and heavy fermions. The bound on the composite Higgs mass is estimated using
the method of Bardeen, Hill and Lindner, 150GeV$\leq m_H\leq$ 450GeV.

</DOC>
<DOC>
<DOCNO> 118576 </DOCNO>
Reanalyses of Voyager Ultraviolet Spectrometer Limits to the EUV and FUV


  We re-examine {\em Voyager} Ultraviolet Spectrograph data used to establish
upper limits to the $\lambda$ 500-900 \AA and $\lambda$ 900-1100 \AA cosmic
diffuse background. The measurement of diffuse flux with the {\em Voyager} UVS
data requires complex corrections for noise sources which are far larger than
the astronomical signal. In the analyses carried out to date, the upper limits
obtained on the diffuse background show statistical anomalies which indicate
that substantial systematic errors are present. We detail these anomalies and
identify specific problems with the analysis. We derive statistically robust
2~$\sigma$ upper limits for continuum flux of 570~photons~s$^{-1}$
cm$^{-2}$~ster$^{-1}$~\AA$^{-1}$ and for the 1000 \AA~ diffuse line flux of
11,790~photons~s$^{-1}$ cm$^{-2}$~ster$^{-1}$. The true limits may be
substantially higher because of unknown systematic uncertainties. The new
statistical limits alone are insufficient to support previous conclusions based
on the {\em Voyager} data including work on the character of interstellar dust
and estimates of the diffuse extragalactic far UV background as absorbed by
intergalactic dust.

</DOC>
<DOC>
<DOCNO> 178421 </DOCNO>
Lambda-Neutron Scattering Lengths from Radiative K-minus Capture


  Radiative capture of the K-minus by the deuteron as a reaction for
measurement of the Lambda-neutron scattering lengths. The use of spin
information to separate the singlet and triplet scattering lengths is treated.

</DOC>
<DOC>
<DOCNO> 83414 </DOCNO>
On a cepstrum-based speech detector robust to white noise


  We study effects of additive white noise on the cepstral representation of
speech signals. Distribution of each individual cepstrum coefficient of speech
is shown to depend strongly on noise and to overlap significantly with the
cepstrum distribution of noise. Based on these studies, we suggest a scalar
quantity, V, equal to the sum of weighted cepstral coefficients, which is able
to classify frames containing speech against noise-like frames. The
distributions of V for speech and noise frames are reasonably well separated
above SNR = 5 dB, demonstrating the feasibility of robust speech detector based
on V.

</DOC>
<DOC>
<DOCNO> 84750 </DOCNO>
Evolution of Cosmological Perturbations in the Brane World


  The evolution of the cosmological perturbations is studied in the context of
the Randall-Sundrum brane world scenario, in which our universe is realized on
a three-brane in the five dimensional Anti-de Sitter(AdS) spacetime. We develop
a formalism to solve the coupled dynamics of the cosmological perturbations in
the brane world and the gravitational wave in the AdS bulk. Using our
formalism, the late time evolution of the cosmological scalar perturbations at
any scales larger than the AdS curvature scale $l$ is shown to be identical
with the one obtained in the conventional 4D cosmology, provided the effect of
heavy graviton modes may be neglected. Here the late time means the epoch when
the Hubble horizon $H^{-1}$ in the 4D brane world is sufficiently larger than
the AdS curvature scale $l$. If the inflation occurs sufficiently lower than
$l^{-1}$, the scalar temperature anisotropies in the Cosmic Microwave
Background at large scales can be calculated using the constancy of the Bardeen
parameter as is done in the 4D cosmology. The assumption of the result is that
the effect of the massive graviton with mass $m e^{-\alpha_0}>l^{-1}$ in the
brane world is negligible, where $e^{\alpha_0}$ is the scale factor of the
brane world. We also discuss the effect of these massive gravitons on the
evolution of the perturbations.

</DOC>
<DOC>
<DOCNO> 169788 </DOCNO>
Measurements in quantum physics: towards a physical picture of relevant


  We propose a new structure of ensembles in quantum theory, based on the
recently introduced intrinsic properties of electrons and photons. On this
statistical basis the spreading of a wave-packet, collapse of the wave
function, the quantum eraser, and interaction-free measurements are re-analyzed
and the usual conceptual problems removed.

</DOC>
<DOC>
<DOCNO> 118768 </DOCNO>
Dust Echos from Gamma Ray Bursts


  The deviation from the power-law decline of the optical flux observed in GRB
970228 and GRB 980326 has been used recently to argue in favor of the
connection between GRBs and supernovae. We consider an alternative explanation
for this phenomenon, based on the scattering of a prompt optical burst by 0.1
solar masses of dust located beyond its sublimation radius 0.1-1 pc from the
burst. In both cases, the optical energy observed at the time of the first
detection of the afterglow suffices to produce an echo after 20-30 days, as
observed. Prompt optical monitoring of future bursts and multiband photometry
of the afterglows will enable quantitative tests of simple models of dust
reprocessing and a prediction of the source redshift.

</DOC>
<DOC>
<DOCNO> 102815 </DOCNO>
Logarithmic orbifold Euler numbers of surfaces with applications


  We introduce orbifold Euler numbers for normal surfaces with Q-divisors.
These numbers behave multiplicatively under finite maps and in the log
canonical case we prove that they satisfy the Bogomolov-Miyaoka-Yau type
inequality. As a corollary we prove effective versions of Bogomolov's result on
boundedness of rational curves in some surfaces of general type. Finally, we
give some applications to singularities of plane curves.

</DOC>
<DOC>
<DOCNO> 150738 </DOCNO>
Realistic regularization of the QED Green functions


  Generalizing the 't Hooft and Veltman method of unitary regulators, we
demonstrate for the first time the existence of local, Lorentz-invariant,
physically motivated Lagrangians of quantum-electrodynamic phenomena such that:
(i) Feynman diagrams are finite and equal the diagrams of QED but with
regularized propagators. (ii) N-point Green functions are C-, P-, and
T-invariant up to a phase factor, Lorentz-invariant and causal. (iii) No
auxiliary particles or parameters are introduced.

</DOC>
<DOC>
<DOCNO> 10759 </DOCNO>
Magnetoresistance in quasi-one-dimensional metals due to Fermi surface


  In a number of quasi-one-dimensional organic metals the dependence of the
magnetoresistance on the direction of the magnetic field is quite different
from the predictions of Boltzmann transport theory for a Fermi liquid with a
scattering rate that is independent of momentum. We consider a model in which
there are large variations in the scattering rate over the Fermi surface. The
model is the quasi-one-dimensional version of the ``cold spots'' model
introduced by Ioffe and Millis to explain anomalous transport properties of the
metallic phase of the cuprate superconductors. The dependence of the
resistance, in the most and least conducting directions, on the direction and
magnitude of the magnetic field are calculated. The calculated
magnetoresistance has a number of properties that are quite distinct from
conventional transport theory such as magic angle effects a significant
magnetoresistance when the field and current are both in the least conducting
direction. However, the model cannot give a complete description of the unusual
properties of (TMTSF)2PF6 at pressures of 8-11 kbar.

</DOC>
<DOC>
<DOCNO> 72059 </DOCNO>
Hadronic final state predictions from CCFM: the hadron-level Monte Carlo


  We discuss a practical formulation of backward evolution for the CCFM
small-$x$ evolution equation and show results from its implementation in the
new Monte Carlo event-generator CASCADE.

</DOC>
<DOC>
<DOCNO> 117531 </DOCNO>
The triple degenerate star WD1704+481


  WD1704+481 is a visual binary in which both components are white dwarfs. We
present spectra of the H-alpha line of both stars which show that one component
(WD1704+481.2 = Sanduleak B = GR 577) is a close binary with two white dwarf
components. Thus, WD1704+481 is the first known triple degenerate star. From
radial velocity measurements of the close binary we find an orbital period of
0.1448d, a mass ratio, q=Mbright/Mfaint of q=0.70+-0.03 and a difference in the
gravitational redshifts of 11.5+-2.3km/s. The masses of the close pair of white
dwarfs predicted by the mass ratio and gravitational redshift difference
combined with theoretical cooling curves are 0.39+-0.05 solar mass and
0.56+-0.07 solar masses. WD1704+481 is therefore also likely to be the first
example of a double degenerate in which the less massive white dwarf is
composed of helium and the other white dwarf is composed of carbon and oxygen.

</DOC>
<DOC>
<DOCNO> 118095 </DOCNO>
ISO-SWS spectroscopy of NGC 1068


  We present ISO-SWS spectroscopy of NGC 1068 for the wavelength range 2.4 to
45um, detecting a total of 36 emission lines. Most of the observed transitions
are fine structure and recombination lines originating in the narrow line
region. We compare the line profiles of optical lines and reddening-insensitive
infrared lines to constrain the dynamical structure and extinction properties
of the NLR. The considerable differences found are most likely explained by two
effects. (1) The spatial structure of the NLR is a combination of a highly
ionized outflow cone and lower excitation extended emission. (2) Parts of the
NLR, mainly in the receding part at velocities above systemic, are subject to
extinction that is significantly suppressing optical emission. Line asymmetries
and net blueshifts remain, however, even for infrared fine structure lines
suffering very little obscuration. This may be either due to an intrinsic
asymmetry of the NLR, or due to a very high column density obscuring component
which is hiding part of the NLR even from infrared view. Mid-infrared emission
of molecular hydrogen in NGC 1068 arises in a dense molecular medium at
temperatures of a few hundred Kelvin that is most likely closely related to the
warm and dense components seen in the near-infrared H2 transitions, and in
millimeter wave tracers of molecular gas. Any emission of the putative pc-scale
molecular torus is likely overwhelmed by this larger scale emission.

</DOC>
<DOC>
<DOCNO> 117690 </DOCNO>
Ongoing Large Surveys for Metal-Poor Stars in the Galactic Halo


  We report on two major surveys for metal-poor stars in the galactic halo, the
HK survey, and the Hamburg/ESO survey, which have been undertaken in order to
provide targets for high-resolution spectroscopy with the Subaru HDS and other
large telescopes. We compare basic properties of these two surveys and their
current status, and add some historical remarks.
  The candidate selection procedures of both surveys are described in detail.
We evaluate the candidate selection by comparing effective yields (EYs) of the
survey techniques for the identification of metal-poor stars. It is found that
EY for stars below [Fe/H]=-2.0 in the HES can be up to 80% for stars selected
by automatic classification from machine-scanned unwidened plates, whereas in
the HK survey, where stars are selected by visual inspection of widened survey
plates, the EY is between 11% and 32%, depending on whether a pre-selection
based on BV photometry has been applied.
  Finally, we describe techniques used for determining stellar parameters of
the survey stars by means of moderate resolution follow-up spectroscopy, and
additional UBV photometry. While follow-up observations of HES stars have just
been started, the HK survey has already produced a list of ~4700 stars with
estimates of [Fe/H] typically precise to +/-0.2 dex, some 1000 of which have
[Fe/H]<-2.0, and roughly 100 of which have [Fe/H]<-3.0.

</DOC>
<DOC>
<DOCNO> 10577 </DOCNO>
Spectroscopic fingerprints of a surface Mott-Hubbard insulator: the case


  We discuss the spectroscopic fingerprints that a surface Mott-Hubbard
insulator should show at the intra-atomic level. The test case considered is
that of the Si-terminated SiC(0001) sqrt{3}xsqrt{3} surface, which is known
experimentally to be insulating. We argue that, due to the Mott-Hubbard
phenomenon, spin unpaired electrons in the Si adatom dangling bonds are
expected to give rise to a Si-2p core level spectrum with a characteristic
three-peaked structure, as seen experimentally. This structure results from the
joint effect of intra-atomic exchange, spatial anisotropy, and spin-orbit
coupling. Auger intensities are also discussed.

</DOC>
<DOC>
<DOCNO> 71652 </DOCNO>
One Loop Soft Supersymmetry Breaking Terms in Superstring Effective


  We perform a systematic analysis of soft supersymmetry breaking terms at the
one loop level in a large class of string effective field theories. This
includes the so-called anomaly mediated contributions. We illustrate our
results for several classes of orbifold models. In particular, we discuss a
class of models where soft supersymmetry breaking terms are determined by quasi
model independent anomaly mediated contributions, with possibly non-vanishing
scalar masses at the one loop level. We show that the latter contribution
depends on the detailed prescription of the regularization process which is
assumed to represent the Planck scale physics of the underlying fundamental
theory. The usual anomaly mediation case with vanishing scalar masses at one
loop is not found to be generic. However gaugino masses and A-terms always
vanish at tree level if supersymmetry breaking is moduli dominated with the
moduli stabilized at self-dual points, whereas the vanishing of the B-term
depends on the origin of the mu-term in the underlying theory. We also discuss
the supersymmetric spectrum of O-I and O-II models, as well as a model of
gaugino condensation. For reference, explicit spectra corresponding to a Higgs
mass of 114 GeV are given. Finally, we address general strategies for
distinguishing among these models.

</DOC>
<DOC>
<DOCNO> 150705 </DOCNO>
String-generated quartic scalar interactions


  The {\em cutting and sewing} procedure is used for getting two-loop order
Feynman diagrams of $\Phi^{4}$-theory with an internal SU(N) symmetry group,
starting from tachyon amplitudes of the open bosonic string theory. In a
suitably defined field theory limit, we reproduce the field theory amplitudes
properly normalized and expressed in the Schwinger parametrization.

</DOC>
<DOC>
<DOCNO> 117529 </DOCNO>
The stellar populations of early-type galaxies in the Fornax cluster


  We have measured central line strengths for a magnitude-limited sample of
early-type galaxies in the Fornax cluster, comprising 11 elliptical (E) and 11
lenticular (S0) galaxies, more luminous than MB=-17. When compared with
single-burst stellar population models we find that the centres of Fornax
ellipticals follow a locus of fixed age and have metallicities varying roughly
from half solar to two times solar. The centres of (lower luminosity)
lenticular galaxies, however, exhibit a substantial spread to younger
luminosity-weighted ages indicating a more extended star formation history.
Galaxies with old stellar populations show tight scaling relations between
metal-line indices and the central velocity dispersion. Remarkably also the
Fe-lines are well correlated with sigma. Our detailed analysis of the stellar
populations suggests that these scaling relations are driven mostly by
metallicity. Galaxies with a young stellar component do generally deviate from
the main relation. In particular the lower luminosity S0s show a large spread.
Furthermore we find that elliptical galaxies and the bulge of one bright S0 are
overabundant in magnesium, where the most luminous galaxies show the strongest
overabundances. The stellar populations of young and faint S0s are consistent
with solar abundance ratios or a weak Mg underabundance. (abriged)

</DOC>
<DOC>
<DOCNO> 121897 </DOCNO>
Absolute Proper Motions of Open Clusters: I. Observational data


  Mean proper motions and parallaxes of 205 open clusters were determined from
their member stars found in the Hipparcos Catalogue. 360 clusters were searched
for possible members, excluding nearby clusters with distances D < 200 pc.
Members were selected using ground based information (photometry, radial
velocity, proper motion, distance from the cluster centre) and information
provided by Hipparcos (proper motion, parallax). Altogether 630 certain and 100
possible members were found. A comparison of the Hipparcos parallaxes with
photometric distances of open clusters shows good agreement. The Hipparcos data
confirm or reject the membership of several Cepheids in the studied clusters.

</DOC>
<DOC>
<DOCNO> 101252 </DOCNO>
Inequalities for the Gamma Function and estimates for the volume of


  We consider $k$-dimensional central sections of the unit ball of $\ell_p^n$
(denoted $B_p^n$) and we prove that their volume are bounded by the volume of
$B_p^n$ whenever $1<p<2$ and $1\le k\le (n-1)/2$ or $k=n-1$. We also consider
$0<p<1$ and other cases. We obtain sharp inequalities involving Gamma Function
in order to get these results.

</DOC>
<DOC>
<DOCNO> 40283 </DOCNO>
Intrinsic Radioactivity in a GSO Crystal and Limits on Double Beta Decay


  Scintillating crystal detector offers potential advantages in low-energy
low-background experiments for particle physics and astrophysics. The GSO
crystal is an interesting detector to explore for future neutrino physics
experiments. The contributions to background due to the various channels of
intrinsic radio-isotopes from the Th-232 and U-238 series are identified and
studied with time-correlation analysis and detailed fits to the spectral shape.
Good agreement is achieved between measured and simulated spectra, indicating
background suppression factors to the 10^{-2} - 10^{-3} level are possible. The
procedures can be adopted for background understanding and suppression in other
low-count-rate experiments where the dominant source of background is from
internal radioactivity. Based on 1656 hours of data taking, limits on the
double beta decay half-life for the various channels in Gd-160 are presented.
The limit for the neutrinoless mode is T^{0 \nu \beta \beta}_{{1/2}} > 2.0(0.8)
X 10^{20} y at 68(90)% confidence level.

</DOC>
<DOC>
<DOCNO> 99367 </DOCNO>
Graph-Laplacians and Dirac Operators on (Infinite) Graphs and the


  We develop a graph-Hilbert-space framework, inspired by non-commutative
geometry, on (infinite) graphs and use it to study spectral properies of
\tit{graph-Laplacians} and so-called \tit{graph-Dirac-operators}. Putting the
various pieces together we define a {\it spectral triplet} sharing most (if not
all, depending on the particular graph model) of the properties of what Connes
calls a \tit{spectral triple}. With the help of this scheme we derive an
explicit expression for the {\it Connes-distance function} on general graphs
and prove both a variety of apriori estimates for it and calculate it for
certain examples of graphs. As a possibly interesting aside, we show that the
natural setting of approaching such problems may be the framework of
\tit{(non-)linear programming} or \tit{optimization}. We compare our results
(arrived at within our particular framework) with the results of other authors
and show that the seeming differences depend on the use of different
graph-geometries and/or Dirac operators.

</DOC>
<DOC>
<DOCNO> 12574 </DOCNO>
The Effect of Large Amplitude Fluctuations in the Ginzburg-Landau Phase


  The lattice Ginzburg-Landau model in d=3 and d=2 is simulated, for different
values of the coherence length $\xi$ in units of the lattice spacing $a$, using
a Monte Carlo method. The energy, specific heat, vortex density $v$, helicity
modulus $\Gamma_\mu$ and mean square amplitude are measured to map the phase
diagram on the plane $T-\xi$. When amplitude fluctuations, controlled by the
parameter $\xi$, become large ($\xi \sim 1$) a proliferation of vortex
excitations occurs changing the phase transition from continuous to first
order.

</DOC>
<DOC>
<DOCNO> 12808 </DOCNO>
Point defects on III-V semiconductor surfaces


  The basic properties of point defects (atomic geometry, the position of
charge-transfer levels, and formation energies) on the (110) surface of GaAs,
GaP, and InP have been calculated employing density-functional theory. Based on
these results we discuss the electronic properties of surface defects, defect
segregation, and compensation.

</DOC>
<DOC>
<DOCNO> 9679 </DOCNO>
Coulomb effects on the transport properties of quantum dots in strong


  We investigate the transport properties of quantum dots placed in strong
magnetic field using a quantum-mechanical ' approach based on the 2D
tight-binding Hamiltonian with direct Coulomb interaction and the
Landauer-B\"{u}ttiker (LB) formalism. The electronic transmittance and the Hall
resistance show Coulomb oscillations and also prove multiple addition
processes. We identify this feature as the 'bunching' of electrons observed in
recent experiments and give an elementary explanation in terms of spectral
characteristics of the dot. The spatial distribution of the added electrons may
distinguish between edge and bulk states and it has specific features for
bunched electrons. The dependence of the charging energy on the number of
electrons is discussed for strong and vanishing magnetic field. The crossover
from the tunneling to quantum Hall regime is analyzed in terms of dot-lead
coupling.

</DOC>
<DOC>
<DOCNO> 116937 </DOCNO>
Design of the Ess RFQs and Chopping Line


  The chopping line is a critical part of the ESS linac in term of technical
realisation of the choppers and preservation of the beam qualities. A new
optimised design of the ESS RFQs and chopping lines is reported. The beam
dynamics has been optimised with H- beam currents up to 100-mA to have safety
margin with respect to the ESS goals. The first RFQ transmits almost 99.7% of
the beam up to 2 MeV. The line with two choppers allows a perfect chopping
between 2 bunches. The second RFQ accelerates the particles up to 5 MeV with a
transmission close to 100%.

</DOC>
<DOC>
<DOCNO> 120408 </DOCNO>
Electron Heating and Cosmic Rays at a Supernova Shock from Chandra X-ray


  In this Letter we use the unprecedented spatial resolution of the Chandra
X-ray Observatory to carry out, for the first time, a measurement of the
post-shock electron temperature and proper motion of a young SNR, specifically
to address questions about the post-shock partition of energy among electrons,
ions, and cosmic rays. The expansion rate, 0.100 +/- 0.025 percent per yr, and
inferred age, ~1000 yr, of E0102.2-7219, from a comparison of X-ray
observations spanning 20 years, are fully consistent with previous estimates
based on studies of high velocity oxygen-rich optical filaments in the remnant.
With a radius of 6.4 pc for the blast wave estimated from the Chandra image,
our expansion rate implies a blast wave velocity of ~6000 km/s and a range of
electron temperatures 2.5 - 45 keV, dependent on the degree of collisionless
electron heating. Analysis of the Chandra ACIS spectrum of the immediate
post-shock region reveals a thermal plasma with abundances and column density
typical of the Small Magellanic Cloud and an electron temperature of 0.4-1 keV.
The measured electron temperature is significantly lower than the plausible
range above, which can only be reconciled if we assume that a significant
fraction of the shock energy, rather than contributing to the heating of the
post-shock electrons and ions, has gone into generating cosmic rays.

</DOC>
<DOC>
<DOCNO> 12029 </DOCNO>
A Statistical Mechanical Approach to Combinatorial Chemistry


  An analogy between combinatorial chemistry and Monte Carlo computer
simulation is pursued. Examples of how to design libraries for both materials
discovery and protein molecular evolution are given. For materials discovery,
the concept of library redesign, or the use previous experiments to guide the
design of new experiments, is introduced. For molecular evolution, examples of
how to use ``biased'' Monte Carlo to search the protein sequence space are
given. Chemical information, whether intuition, theoretical calculations, or
database statistics, can be naturally incorporated as an a priori bias in the
Monte Carlo approach to library design in combinatorial chemistry. In this
sense, combinatorial chemistry can be viewed as an extension of traditional
chemical synthesis.

</DOC>
<DOC>
<DOCNO> 85554 </DOCNO>
BF Actions for the Husain-Kuchar Model


  We show that the Husain-Kuchar model can be described in the framework of BF
theories. This is a first step towards its quantization by standard
perturbative QFT techniques or the spin-foam formalism introduced in the
space-time description of General Relativity and other diff-invariant theories.
The actions that we will consider are similar to the ones describing the
BF-Yang-Mills model and some mass generating mechanisms for gauge fields. We
will also discuss the role of diffeomorphisms in the new formulations that we
propose.

</DOC>
<DOC>
<DOCNO> 10090 </DOCNO>
Phononic crystals with planar defects


  We study the effect of planar defects in phononic crystals of spherical
scatterers. It is shown that a plane of impurity spheres introduces modes of
vibration of the elastic field localized on this plane at frequencies within a
frequency gap of a pure phononic crystal; these show up as sharp resonances in
the transmittance of elastic waves incident on a slab of the crystal. A
periodic arrangement of impurity planes along a given direction creates narrow
impurity bands with a width which depends on the position of these bands within
the frequency gap of the pure crystal and on the separation between the
impurity planes. We show how a slight deviation from periodicity (one impurity
plane is different from the rest) reduces dramatically the transmittance of
elastic waves incident on a slab of the crystal.

</DOC>
<DOC>
<DOCNO> 102379 </DOCNO>
Factorizing twists and R-matrices for representations of the quantum


  We calculate factorizing twists in evaluation representations of the quantum
affine algebra U_q(\hat sl_2). From the factorizing twists we derive a
representation independent expression of the R-matrices of U_q(\hat sl_2).
Comparing with the corresponding quantities for the Yangian Y(sl_2), it is
shown that the U_q(\hat sl_2) results can be obtained by `replacing numbers by
q-numbers'. Conversely, the limit q -> 1 exists in representations of U_q(\hat
sl_2) and both the factorizing twists and the R-matrices of the Yangian Y(sl_2)
are recovered in this limit.

</DOC>
<DOC>
<DOCNO> 12404 </DOCNO>
Disclination Unbinding Transition in Quantum Hall Liquid Crystals


  We derive the the long-wavelength elastic theory for the quantum Hall smectic
state starting from the Hartree-Fock approximation. Dislocations in this state
lead to an effective nematic model for $T>0$, which undergoes a disclination
unbinding transition from a phase with algebraic orientational order into an
isotropic phase. We obtain transition temperatures which are in qualitative
agreement with recent experiments which have observed large anisotropies of the
longitudinal resistivities in half-filled Landau levels, lending credence to
the liquid crystal interpretation of experiments.

</DOC>
<DOC>
<DOCNO> 12676 </DOCNO>
Domain State Model for Exchange Bias


  Monte Carlo simulations of a system consisting of a ferromagnetic layer
exchange coupled to a diluted antiferromagnetic layer described by a classical
spin model show a strong dependence of the exchange bias on the degree of
dilution in agreement with recent experimental observations on Co/CoO bilayers.
These simulations reveal that diluting the antiferromagnet leads to the
formation of domains in the volume of the antiferromagnet carrying a remanent
surplus magnetization which causes and controls exchange bias. To further
support this domain state model for exchange bias we study in the present paper
the dependence of the bias field on the thickness of the antiferromagnetic
layer. It is shown that the bias field strongly increases with increasing film
thickness and eventually goes over a maximum before it levels out for large
thicknesses. These findings are in full agreement with experiments.

</DOC>
<DOC>
<DOCNO> 170341 </DOCNO>
Bell's theorem without inequalities and without probabilities for two


  A proof of Bell's theorem using two maximally entangled states of two qubits
is presented. It exhibits a similar logical structure to Hardy's argument of
``nonlocality without inequalities''. However, it works for 100% of the runs of
a certain experiment. Therefore, it can also be viewed as a
Greenberger-Horne-Zeilinger-like proof involving only two spacelike separated
regions.

</DOC>
<DOC>
<DOCNO> 101666 </DOCNO>
On the order of the unitary subgroup of modular group algebra


  Let KG be a group algebra of a finite p-group G over a finite field K of
characteristic p. We compute the order of the unitary subgroup of the group of
units when G is either an extraspecial 2-group or the central product of such a
group with a cyclic group of order 4 or G has an abelian subgroup A of index 2
and an element b such that b inverts each element of A.

</DOC>
<DOC>
<DOCNO> 178537 </DOCNO>
Neutron density distributions for atomic parity nonconservation


  The neutron distributions of Cs, Ba, Yb and Pb isotopes are described in the
framework of relativistic mean-field theory. The self-consistent ground state
proton and neutron density distributions are calculated with the relativistic
Hartree-Bogoliubov model. The binding energies, the proton and neutron radii,
and the quadrupole deformations are compared with available experimental data,
as well as with recent theoretical studies of the nuclear structure corrections
to the weak charge in atomic parity nonconservation experiments.

</DOC>
<DOC>
<DOCNO> 70877 </DOCNO>
Obtaining the Spin of the Proton from the Spins of the Quarks


  Employing the experimental electro-weak interactions between quarks and
leptons, the spin of the proton may easily be understood in terms of the spins
of the constituent quarks.

</DOC>
<DOC>
<DOCNO> 68906 </DOCNO>
A Possible Two-Component Structure of the Non-Perturbative Pomeron


  We propose a QCD-inspired two-component Pomeron form which gives an excellent
description of the proton-proton, pi-proton, kaon-proton, gamma-proton and
gamma-gamma total cross sections. Our fit has a better CHI2/dof for a smaller
number of parameters as compared with the PDG fit. Our 2-Pomeron form is fully
compatible with weak Regge exchange-degeneracy, universality, Regge
factorization and the generalized vector dominance model.

</DOC>
<DOC>
<DOCNO> 8419 </DOCNO>
Analytical Charge-Control Model for DH-HEMT


  A new and simple analytical charge-control model of the two-dimensional
electron gas of a double-heterojunction AlGaAs/GaAs/AlGaAs HEMT is described.
It is found that, despite its simplicity, the charge-control model gives an
accurate description of the device operation for a wide range of physical
parameters. The validity of the analytical model is supported by the calculated
results of the self-consistent quantum mechanical model and agrees with
previously reported theoretical and experimental data. The influence of some
physical parameters on the device performance is also discussed.

</DOC>
<DOC>
<DOCNO> 71105 </DOCNO>
Compact Variables and Singular Fields in QCD


  Subject of our investigations is QCD formulated in terms of physical degrees
of freedom. Starting from the Faddeev-Popov procedure, the canonical
formulation of QCD is derived for static gauges. Particular emphasis is put on
obstructions occurring when implementing gauge conditions and on the
concomitant emergence of compact variables and singular fields. A detailed
analysis of non-perturbative dynamics associated with such exceptional field
configurations within Coulomb- and axial gauge is described. We present
evidence that compact variables generate confinement-like phenomena in both
gauges and point out the deficiencies in achieving a satisfactory
non-perturbative treatment concerning all variables. Gauge fixed formulations
are shown to constitute also a useful framework for phenomenological studies.
Phenomenological insights into the dynamics of Polyakov loops and monopoles in
confined and deconfined phases are presented within axial gauge QCD

</DOC>
<DOC>
<DOCNO> 13317 </DOCNO>
Magnetism, Spin-Orbit Coupling, and Superconducting Pairing in UGe$_2$


  A consistent picture on the mean-field level of the magnetic properties and
electronic structure of the superconducting itinerant ferromagnet UGe$_2$ is
shown to require inclusion of correlation effects beyond the local density
approximation (LDA). The "LDA+U" approach reproduces both the magnitude of the
observed moment, composed of strongly opposing spin and orbital parts, and the
magnetocrystalline anisotropy. The largest Fermi surface sheet is comprised
primarily of spin majority states with orbital projection $m_{\ell}$=0,
suggesting a much simpler picture of the pairing than is possible for general
strong spin-orbit coupled materials. This occurrence, and the
quasi-two-dimensional geometry of the Fermi surface, support the likelihood of
magnetically mediated p-wave triplet pairing.

</DOC>
<DOC>
<DOCNO> 170669 </DOCNO>
Experimental Test of Complementarity by Nuclear Magnetic Resonance


  We have tested complementarity for the ensemble-averaged spin states of
nuclei $^{13}$C in the molecule of $^{13}$CHCl$_{3}$ by the use of the spin
states of another nuclei $^{1}$H as the path marker. It turns out that the
wave-particle duality holds when one merely measures the probability density of
quantum states, and that the wave- and particle-like behavior is simultaneously
observed with the help of measuring populations and coherence in a single
nuclear magnetic resonance(NMR) experiment. Effects of path-marking schemes and
causes of the appearance and disappearance of the wave behavior are analysed.

</DOC>
<DOC>
<DOCNO> 101953 </DOCNO>
RC-graphs and a generalized Littlewood-Richardson rule


  Using a generalization of the Schensted insertion algorithm to rc-graphs, we
provide a Littlewood-Richardson rule for multiplying certain Schubert
polynomials by Schur polynomials.

</DOC>
<DOC>
<DOCNO> 99796 </DOCNO>
Quadratic-linar algebras associated with factorizations of


  This is the first of series of talks presented at a permanent Rutgers
workshop on noncommutative algebra and geometry. We study here quadratic and
quadratic-linear algebras defined by factorizations of noncommutative
polynomials and differential polynomials. Such algebras posses a natural
derivation and give us a new understanding of a nature of noncommutative
symmetric functions.

</DOC>
<DOC>
<DOCNO> 13267 </DOCNO>
Localization-Delocalization Transition in a Quantum Dot


  A model Hamiltonian is proposed in order to understand the
localization-delocalization transition in a quantum dot, where there are two
gate voltages: top and side. Considering energetically favorable degrees of
freedom only, we achieve a finite dimensional Hilbert space. As a result, exact
diagonalization is performed to find the ground state energy of the system. It
is the purpose to explain the peculiar pattern of the electron addition energy
measured in the dot of two gate voltages.

</DOC>
<DOC>
<DOCNO> 101598 </DOCNO>
Global existence for a quasilinear wave equation outside of star-shaped


  We establish global existence in 3+1 dimensions of small-amplitude solutions
of quasilinear Dirichlet-wave equations satisfying the null condition outside
of star-shapped obstacles.

</DOC>
<DOC>
<DOCNO> 150971 </DOCNO>
Type IIB orbifolds with D5-branes and their string duals


  We consider Z2, freely acting orbifolds of the type IIB string with 16
parallel D5-branes. When the string is compactified on T2 X T4 and the
D5-branes are wrapped on T2, these systems possess N=2 supersymmetry,
originating from the spontaneous, partial breaking of N=4. Extended
supersymmetry allows us to investigate the duality with certain heterotic and
type I constructions, and to obtain informations about their non-perturbative
regime.

</DOC>
<DOC>
<DOCNO> 118867 </DOCNO>
A TiO study of the dwarf nova IP Pegasi


  We present red spectra in the region 7000-8300A of the eclipsing dwarf nova
IP Peg, with simultaneous narrow-band photometry centered at 7322A. We show
that by placing a second star on the slit we can correct for the telluric
absorption bands which have hitherto made the TiO features from the secondary
star unusable. We use these TiO features to carry out a radial velocity study
of the secondary star, and find this gives an improvement in signal-to-noise of
a factor two compared with using the Na{I} doublet. In contrast with previous
results, we find no apparent ellipticity in the radial velocity curve. As a
result we revise the semi-amplitude to 331.3+/-5.8km/s, and thus the primary
and secondary star masses to 1.05Mo and 0.33Mo respectively. Although this is
the lowest mass yet derived for the secondary star, it is still over-massive
for its observed spectral type. However, the revised mass and radius bring IP
Peg into line with other CVs in the mass-radius-period relationships.
  By fitting the phase resolved spectra around the TiO bands to a mean
spectrum, we attempt to isolate the lightcurve of the secondary star. The
resulting light curve has marked deviations from the expected ellipsoidal
shape. The largest difference is at phase 0.5, and can be explained as an
eclipse of the secondary star by the disc, indicating that the disc is
optically thick when viewed at high inclination angles.

</DOC>
<DOC>
<DOCNO> 80739 </DOCNO>
Symmetry Nonrestoration in a Gross-Neveu Model with Random Chemical


  We study the symmetry behavior of the Gross-Neveu model in three and two
dimensions with random chemical potential. This is equivalent to a four-fermion
model with charge conjugation symmetry as well as Z_2 chiral symmetry. At high
temperature the Z_2 chiral symmetry is always restored. In three dimensions the
initially broken charge conjugation symmetry is not restored at high
temperature, irrespective of the value of the disorder strength. In two
dimensions and at zero temperature the charge conjugation symmetry undergoes a
quantum phase transition from a symmetric state (for weak disorder) to a broken
state (for strong disorder) as the disorder strength is varied. For any given
value of disorder strength, the high-temperature behavior of the charge
conjugation symmetry is the same as its zero-temperature behavior. Therefore,
in two dimensions and for strong disorder strength the charge conjugation
symmetry is not restored at high temperature.

</DOC>
<DOC>
<DOCNO> 71095 </DOCNO>
Extended HQEFT Lagrangian and currents


  From the tree-level heavy quark effective Lagrangian keeping
particle-antiparticle mixed sectors we derive the vector current coupling to a
hard gluonic field allowing for heavy quark-antiquark pair annihilation and
creation.

</DOC>
<DOC>
<DOCNO> 10259 </DOCNO>
Response of the two-dimensional electron gas of AlGaAs/GaAs


  We study the transport properties of the two-dimensional electron gas in
AlGaAs/GaAs heterostructures in parallel to the interface magnetic fields at
low temperatures. The magnetoresistance in the metallic phase is found to be
positive and weakly anisotropic with respect to the orientation of the in-plane
magnetic field and the current through the sample. At low electron densities
($n_s< 5\times 10^{10}$ cm$^{-2}$) the experimental data can be described
adequately within spin-related approach while at high $n_s$ the
magnetoresistance mechanism changes as inferred from $n_s$-independence of the
normalized magnetoresistance.

</DOC>
<DOC>
<DOCNO> 120294 </DOCNO>
The constant density region of the dark halos of spiral galaxies


  From the kinematics of 137 spirals we find that the DM halo density profiles
are self-similar at least out to R_opt and show core radii much larger that the
corresponding disk scale-lenghts. The luminous regions of spirals consist of
stellar disks embedded in dark halos with roughly constant density. With
respect to previous work, the present evidence is obtained by means of a robust
method and for a large and complete sample of normal spirals.

</DOC>
<DOC>
<DOCNO> 10711 </DOCNO>
Enhancement of magnetoresistance in manganite multilayers


  Magnanite multilayers have been fabricated using La0.67Ca0.33MnO3 as the
ferromagnetic layer and Pr0.7Ca0.3MnO3 and Nd0.5Ca0.5MnO3 as the spacer layers.
All the multilayers were grown on LaAlO3 (100) by pulse laser deposition. An
enhanced magnetoresistnace (defined (RH- R0)/R0) of more than 98% is observed
in these multilayers. Also a low field magnetoresistance of 41% at 5000 Oe is
observed in these multilayer films. The enhanced MR is attributed to the
induced double exchange in the spacer layer, which is giving rise to more
number of conducting carriers. This is compared by replacing the spacer layer
with LaMnO3 where Mn exists only in 3+ state and no enhancement is observed in
the La0.67Ca0.33MnO3 / LaMnO3 multilayers as double exchange mechanism can not
be induced by external magnetic fields.

</DOC>
<DOC>
<DOCNO> 40432 </DOCNO>
Inclusive pi0 and K0s in gamma-gamma at L3


  The ee -> ee+pi0+X and ee -> ee+K0s+X reactions are studied at LEP using data
collected with the L3 detector at sqrt{s}=189-202 GeV. Preliminary results for
the differential cross section dsigma/dpt in the transverse momentum range 0.2
GeV < pt < 7.5 GeV at central values of pseudo-rapidity, |eta| < 0.5 or |eta| <
1.5, and the differential cross section dsigma/d|eta| for different values of
pt are presented. For pt le 1 GeV, the pt -dependence of the data are well
described by an exponential fit. For pt > 1 GeV the cross sections are compared
to NLO QCD calculations and to LO Monte Carlo predictions.

</DOC>
<DOC>
<DOCNO> 123201 </DOCNO>
Signatures in a Giant Radio Galaxy of a Cosmological Shock Wave at


  Sensitive images of low-level, Mpc-sized radio cocoons offer new
opportunities to probe large scale intergalactic gas flows outside clusters of
galaxies. New radio images of high surface brightness sensitivity at
strategically chosen wavelengths of the giant radio galaxy NGC 315 (Mack et al.
1997,1998) reveal significant asymmetries and particularities in the
morphology, radio spectrum and polarization of the ejected radio plasma. We
argue that the combination of these signatures provides a sensitive probe of an
environmental shock wave. Analysis of optical redshifts in NGC 315 vicinity
confirms its location to be near, or at a site of large-scale flow collisions
in the 100 Mpc sized Pisces-Perseus Supercluster region. NGC 315 resides at the
intersection of several galaxy filaments, and its radio plasma serves there as
a `weather station' (Burns 1998) probing the flow of the elusive and previously
invisible IGM gas. If our interpretation is correct, this is the first
indication for a shock wave in flows caused by the cosmological large scale
structure formation, which is located in a filament of galaxies. The
possibility that the putative shock wave is a source of gamma-rays and ultra
high energy cosmic rays is briefly discussed.

</DOC>
<DOC>
<DOCNO> 9257 </DOCNO>
Dipolar ordering in Fe8?


  We show that the low-temperature physics of molecular nanomagnets, contrary
to the prevailing one-molecule picture, must be determined by the long-range
magnetic ordering due to many-body dipolar interactions. The calculations here
performed, using Ewald's summation, suggest a ferromagnetic ground state with a
Curie temperature of about 130 mK. The energy of this state is quite close to
those of an antiferromagnetic state and to a glass of frozen spin chains. The
latter may be realized at finite temperature due to its high entropy.

</DOC>
<DOC>
<DOCNO> 85580 </DOCNO>
R-mode oscillations of differentially and rapidly rotating Newtonian


  For the analysis of the r-mode oscillation of hot young neutron stars, it is
necessary to consider the effect of it differential rotation, because viscosity
is not strong enough for differentially rotating young neutron stars to be lead
to uniformly rotating configurations on a very short time scale after their
birth. In this paper, we have developed a numerical scheme to solve r-mode
oscillations of differentially rotating polytropic inviscid stars. This is the
extended version of the method which was applied to compute r-mode oscillations
of uniformly rotating Newtonian polytropic stars. By using this new method, we
have succeeded in obtaining eigenvalues and eigenfunctions of r-mode
oscillations of differentially rotating polytropic stars. Our numerical results
show that as the degree of differential rotation is increased, it becomes more
difficult to solve r-mode oscillations for slightly deformed configurations
from sphere compared to solving r-mode oscillations of considerably deformed
stars. One reason for it seems that for slightly deformed stars corotation
points appear near the surface region if the degree of differential rotation is
strong enough. This is similar to the situation that the perturbational
approach of r-mode oscillations for it slowly rotating stars in general
relativity results in a singular eigenvalue problem.

</DOC>
<DOC>
<DOCNO> 40612 </DOCNO>
Precise Determination of the Z Resonance Parameters at LEP : Zedometry


  This final analysis of hadronic and leptonic cross-sections and of leptonic
forward-backward asymmetries in e+e- collisions with the OPAL detector makes
use of the full LEP1 data sample comprising 161 pb^-1 of integrated luminosity
and 4.5 x 10^6 selected Z decays. An interpretation of the data in terms of
contributions from pure Z exchange and from Z-gamma interference allows the
parameters of the Z resonance to be determined in a model-independent way. Our
results are in good agreement with lepton universality and consistent with the
vector and axial-vector couplings predicted in the Standard Model. A fit to the
complete dataset yields the fundamental Z resonance parameters: mZ = 91.1852 +-
0.0030 GeV, GZ = 2.4948 +- 0.0041 GeV, s0h = 41.501 +- 0.055 nb, Rl = 20.823 +-
0.044, and Afb0l = 0.0145 +- 0.0017. Transforming these parameters gives a
measurement of the ratio between the decay width into invisible particles and
the width to a single species of charged lepton, Ginv/Gl = 5.942 +- 0.027.
Attributing the entire invisible width to neutrino decays and assuming the
Standard Model couplings for neutrinos, this translates into a measurement of
the effective number of light neutrino species, N_nu = 2.984 +- 0.013.
Interpreting the data within the context of the Standard Model allows the mass
of the top quark, mt = 162 +29-16 GeV, to be determined through its influence
on radiative corrections. Alternatively, utilising the direct external
measurement of mt as an additional constraint leads to a measurement of the
strong coupling constant and the mass of the Higgs boson: alfa_s(mZ) = 0.127 +-
0.005 and mH = 390 +750-280 GeV.

</DOC>
<DOC>
<DOCNO> 10932 </DOCNO>
withdrawn


  This paper has been withdrawn by the authors due to new experimental results.

</DOC>
<DOC>
<DOCNO> 116558 </DOCNO>
A Cupronickel Rotating Band Pion Production Target for Muon Colliders


  A conceptual design is presented for a high power cupronickel pion production
target. It forms a circular band in a horizontal plane with approximate
dimensions of: 2.5 meters radius, 6 cm high and 0.6 cm thick. The target is
continuously rotated at 3 m/s to carry heat away from the production region to
a water cooling channel. Bunches of 16 GeV protons with total energies of 270
kJ and repetition rates of 15 Hz are incident tangentially to arc of the target
along the symmetry axis of a 20 Tesla solenoidal magnetic capture channel. The
mechanical layout and cooling setup are described. Results are presented from
realistic MARS Monte Carlo computer simulations of the pion yield and energy
deposition in the target. ANSYS finite element calculations are beginning to
give predictions for the resultant shock heating stresses.

</DOC>
<DOC>
<DOCNO> 40061 </DOCNO>
Physics at high Q^2 and p^2_t: Summary of DIS 2000


  We summarize the experimental and theoretical results presented in the
"Physics at the Highest Q^2 and p^2_t" working group at the DIS 2000 Workshop.
High Q^2 and p^2_t processes measured at current and future colliders allow to
improve our knowledge of Standard Model (SM) physics, by providing precise
measurements of the SM parameters and, consequently, consistency checks of the
SM. Moreover, they give information on key quantities for the calculation of
the SM expectations in a yet unexplored domain, such as the parton densities of
the proton or the photon. In addition to these experimental inputs,
higher-order calculations are also needed to obtain precise expectations for SM
processes, which are a key ingredient for the searches for new phenomena in
high Q^2 and p^2_t processes at current and future experiments. The
experimental and theoretical status of SM physics at high Q^2 and p^2_t is
reviewed in the first part of this summary, with the remaining being dedicated
to physics beyond the Standard Model.

</DOC>
<DOC>
<DOCNO> 69736 </DOCNO>
Broadening of Transverse Momentum of Partons Propagating through a


  Broadening of the transverse momentum of a parton propagating through a
medium is treated using the color dipole formalism, which has the advantage of
being a well developed phenomenology in deep-inelastic scattering and soft
processes. Within this approach, nuclear broadening should be treated as color
filtering, i.e. absorption of large-size dipoles leading to diminishing
(enlarged) transverse separation (momentum). We also present a more intuitive
derivation based on the classic scattering theory of Moli\`ere. This derivation
helps to understand the origin of the dipole cross section, part of which comes
from attenuation of the quark, while another part is due to multiple
interactions of the quark. It also demonstrates that the lowest-order
rescattering term provides an A-dependence very different from the generally
accepted A^{1/3} behavior. The effect of broadening increases with energy, and
we evaluate it using different phenomenological models for the unintegrated
gluon density. Although the process is dominated by soft interactions, the
phenomenology we use is tested using hadronic cross section data.

</DOC>
<DOC>
<DOCNO> 101569 </DOCNO>
On the algebraic invariant curves of plane polynomial differential


  We consider a plane polynomial vector field $P(x,y)dx+Q(x,y)dy$ of degree
$m>1$. To each algebraic invariant curve of such a field we associate a compact
Riemann surface with the meromorphic differential $\omega=dx/P=dy/Q$. The
asymptotic estimate of the degree of an arbitrary algebraic invariant curve is
found. In the smooth case this estimate was already found by D. Cerveau and A.
Lins Neto [Ann. Inst. Fourier Grenoble 41, 883-903] in a different way.

</DOC>
<DOC>
<DOCNO> 70514 </DOCNO>
Symmetry-breaking corrections to heavy-to-light B meson form factors at


  Recently it has been shown that symmetries emerging in the heavy quark and
large recoil energy limit impose various relations on form factors that
parametrise the decay of B mesons into light mesons. These symmetries are
broken by perturbative effects. In this paper we discuss the structure of
heavy-to-light form factors including such effects and compute
symmetry-breaking corrections to first order in the strong coupling. As an
application of our results we consider the forward-backward asymmetry zero in
the rare decay B -> V l^+ l^- and the possibility to constrain potential new
physics contributions to the Wilson coefficient C_9.

</DOC>
<DOC>
<DOCNO> 39822 </DOCNO>
Z boson pair production in e+e- collisions at sqrt(s) = 183 and 189 GeV


  A study of Z boson pair production in e+e- annihilation at center-of-mass
energies near 183 GeV and 189 GeV is reported. Final states containing only
leptons, (l+l-l+l- and l+l-nu nubar), quark and lepton pairs, (q qbar l+l-, q
qbar nu nubar) and the all-hadronic final state (q qbar q qbar) are considered.
In all states with at least one Z boson decaying hadronically, q qbar and b
bbar final states are considered separately using lifetime and event-shape
tags, thereby improving the cross-section measurement. At sqrt(s) = 189 GeV the
Z-pair cross section was measured to be 0.80 (+0.14-0.13, stat.) (+0.06-0.05,
syst.) pb, consistent with the Standard Model prediction. At sqrt(s) = 183 GeV
the 95% C.L. upper limit is 0.55 pb. Limits on anomalous ZZgamma and ZZZ
couplings are derived.

</DOC>
<DOC>
<DOCNO> 101051 </DOCNO>
Unified description of quantum affine (super)algebras U_q(A_{1}^{(1)})


  We show that the quantum affine algebra U_{q}(A_{1}^{(1)}) and the quantum
affine superalgebra U_{q}(C(2)^{(2)}) admit unified description. The difference
between them consists in the phase factor which is equal to 1 for
U_{q}(A_{1}^{(1)}) and is equal to -1 for U_{q}(C(2)^{(2)}). We present such a
description for the construction of Cartan-Weyl generators and their
commutation relations, as well for the universal R-matrices.

</DOC>
<DOC>
<DOCNO> 116298 </DOCNO>
Finite-Correlation-Time Effects in the Kinematic Dynamo Problem


  Most of the theoretical results on the kinematic amplification of small-scale
magnetic fluctuations by turbulence have been confined to the model of
white-noise-like advecting turbulent velocity field. In this work, the
statistics of the passive magnetic field in the diffusion-free regime are
considered for the case when the advecting flow is finite-time correlated. A
new method is developed that allows one to systematically construct the
correlation-time expansion for statistical characteristics of the field. The
expansion is valid provided the velocity correlation time is smaller than the
characteristic growth time of the magnetic fluctuations. This expansion is
carried out up to first order in the general case of a d-dimensional
arbitrarily compressible advecting flow. The growth rates for all moments of
the magnetic field are derived. The effect of the first-order corrections is to
reduce these growth rates. It is shown that introducing a finite correlation
time leads to the loss of the small-scale statistical universality, which was
present in the limit of the delta-correlated velocity field. Namely, the shape
of the velocity time-correlation profile and the large-scale spatial structure
of the flow become important. The latter is a new effect, that implies, in
particular, that the approximation of a locally-linear shear flow does not
fully capture the effect of nonvanishing correlation time. Physical
applications of this theory include the small-scale kinematic dynamo in the
interstellar medium and protogalactic plasmas.

</DOC>
<DOC>
<DOCNO> 39779 </DOCNO>
Spin Physics with the STAR detector


  The STAR detector will bring unique capabilities to the study of
$\vec{p}+\vec{p}$ collisions up to total center of mass energies of 500 GeV at
RHIC. The large acceptance of the time projection chamber and the
electromagnetic calorimeter enable STAR to observe jets, and to detect photons
and electrons in important regions of phase space. The premier experiments of
the STAR spin program are discussed in this contribution. Photon + jet
coincidence measurements will provide the world's best determination of the
contribution gluons make to the proton's spin. Detection of the daughter
electrons and positrons from $W^\pm$ decay will enable the determination of the
polarization of the $q\bar{q}$ sea within the proton.

</DOC>
<DOC>
<DOCNO> 8827 </DOCNO>
Excluded volume effects on the structure of a linear polymer under shear


  The effect of excluded volume interactions on the structure of a polymer in
shear flow is investigated by Brownian Dynamics simulations for chains with
size $30\leq N\leq 300$. The main results concern the structure factor $S({\bf
q})$ of chains of N=300 Kuhn segments, observed at a reduced shear rate
$\beta=\dot{\gamma}\tau=3.2$, where $\dot{\gamma}$ is the bare shear rate and
$\tau$ is the longest relaxation time of the chain. At low q, where anisotropic
global deformation is probed, the chain form factor is shown to match the form
factor of the continuous Rouse model under shear at the same reduced shear
rate, computed here for the first time in a wide range of wave vectors. At high
q, the chain structure factor evolves towards the isotropic equilibrium power
law $q^{-1/\nu}$ typical of self-avoiding walk statistics. The matching between
excluded volume and ideal chains at small q, and the excluded volume power law
behavior at large q are observed for ${\bf q}$ orthogonal to the main
elongation axis but not yet for ${\bf q}$ along the elongation direction
itself, as a result of interferences with finite extensibility effects. Our
simulations support the existence of anisotropic shear blobs for polymers in
good solvent under shear flow for $\beta>1$ provided chains are sufficiently
long.

</DOC>
<DOC>
<DOCNO> 39713 </DOCNO>
The Nucleon Anapole Moment and Parity-Violating ep Scattering


  Parity-violating (PV) interactions among quarks in the nucleon induce a PV
$\gamma NN$ coupling, or anapole moment (AM). We compute electroweak
gauge-independent contributions to the AM through ${\cal O}(1/\lamchis)$ in
chiral perturbation theory. We estimate short-distance PV effects using
resonance saturation. The AM contributions to PV electron-proton scattering
slightly enhance the axial vector radiative corrections, R_A^p, over the scale
implied by the Standard Model when weak quark-quark interactions are neglected.
We estimate the theoretical uncertainty associated with the AM contributions to
R_A^p to be large, and discuss the implications for the interpretation PV of ep
scattering.

</DOC>
<DOC>
<DOCNO> 13604 </DOCNO>
Comparing schemes of displacement detection and subharmonic generation


  We present measurements on nanomechanical resonators operating in the radio
frequency range. We apply a setup which allows the comparison of two schemes of
displacement detection for mechanical resonators, namely conventional power
reflection measurements of a probing signal and direct detection by capacitive
coupling via a gate electrode. For capacitive detection, we employ an on-chip
preamplifier, which enables direct measurements of the resonator's
displacement. We observe that the response of the mechanical resonator depends
on the detection technique applied, which is verified in model calculations. We
show results on the detection of subharmonics.

</DOC>
<DOC>
<DOCNO> 8937 </DOCNO>
Spin-Gap States of a Periodic Mixed Spin Chain


  We examine a chain of periodic arrays of 4 quantum spins with magnitudes of
1/2, 1, 3/2 and 1. There are four kinds of nearest-neighbour exchange
parameters among them. We choose two independent parameters for concreteness:
one represents the ratio of typical exchange parameters, and the other
represents a distortion. We determine the phase diagram of the ground state in
the parameter space. The phase boundaries appear as gapless lines which
separate gapful disordered phases. They are determined by the gapless equation
which was previously derived by mapping a general periodic spin chain to the
nonlinear $\sigma$ model.

</DOC>
<DOC>
<DOCNO> 150535 </DOCNO>
Curing the Infinite Ghost Tower in 4d Siegel Superparticle


  On an explicit example of the Siegel superparticle we study an alternative to
the harmonic superspace approach. The latter seems to be the only method for
quantizing infinitely reducible first class constraints currently available. In
an appropriately extended phase space, the infinite ghost tower is effectively
canceled by that coming from the sector of auxiliary variables. After a proper
BRST treatment the theory proves to be of rank two which correlates well with
the results obtained earlier within the framework of the harmonic superspace
approach. The advantage of the novel technique, however, is the existence of an
explicit Lagrangian formulation and the standard spin--statistics relations
which hold for all the variables involved.

</DOC>
<DOC>
<DOCNO> 69523 </DOCNO>
Anisotropic transverse flow and the quark-hadron phase transition


  We use (3+1)-dimensional hydrodynamics with exact longitudinal
boost-invariance to study the influence of collision centrality and initial
energy density on the transverse flow pattern and the angular distributions of
particles emitted near midrapidity in ultrarelativistic heavy-ion collisions.
We concentrate on radial flow and the elliptic flow coefficient v2 as functions
of the impact parameter and of the collision energy. We demonstrate that the
finally observed elliptic flow is established earlier in the collision than the
observed radial flow and thus probes the equation of state at higher energy
densities. We point out that a phase transition from hadronic matter to a
color-deconfined quark-gluon plasma leads to non-monotonic behaviour in both
beam energy and impact parameter dependences which, if observed, can be used to
identify such a phase transition. Our calculations span collision energies from
the Brookhaven AGS (Alternating Gradient Synchrotron) to beyond the LHC (Large
Hadron Collider); the QGP phase transition signature is predicted between the
lowest available SPS (CERN Super Proton Synchrotron) and the highest RHIC
(Brookhaven Relativistic Heavy Ion Collider) energies. To optimize the chances
for applicability of hydrodynamics we suggest to study the excitation function
of flow anisotropies in central uranium-uranium collisions in the side-on-side
collision geometry.

</DOC>
<DOC>
<DOCNO> 119308 </DOCNO>
Spectroscopic confirmation of clusters from the ESO imaging survey


  We measure redshifts for 67 galaxies in the field of six cluster candidates
from the ESO Imaging Survey (EIS). The cluster candidates are selected in the
EIS patches C and D among those with estimated mean redshifts between 0.5 and
0.7. The observations were made with EFOSC2 at the 3.6m ESO telescope.
  In the six candidate cluster fields, we identify 19 possible sets of 2 to 7
galaxies in redshift space. In order to establish which of the 19 sets are
likely to correspond to real dense systems we compare our counts with those
expected from a uniform distribution of galaxies with given luminosity
function. In order to take into account the effect of the Large Scale
Structure, we modulate the probability computed from the luminosity function
with random samplings of the Canada-France Redshift Survey.
  We find that four out of six candidate EIS clusters are likely to correspond
to real systems in redshift space (> 95 % confidence level). Two of these
systems have mean redshift in agreement with the redshift estimate given by the
matched filter algorithm. The other two systems have significantly lower
redshifts.
  We discuss the implications of our results in the context of our ongoing
research projects aimed at defining high-redshift optically-selected cluster
samples.

</DOC>
<DOC>
<DOCNO> 85030 </DOCNO>
Conversion of conventional gravitational-wave interferometers into QND


  The LIGO-II gravitational-wave interferometers (ca. 2006--2008) are designed
to have sensitivities at about the standard quantum limit (SQL) near 100 Hz.
This paper describes and analyzes possible designs for subsequent, LIGO-III
interferometers that can beat the SQL. These designs are identical to a
conventional broad-band interferometer (without signal recycling), except for
new input and/or output optics. Three designs are analyzed: (i) a
"squeezed-input interferometer" (conceived by Unruh based on earlier work of
Caves) in which squeezed vacuum with frequency-dependent (FD) squeeze angle is
injected into the interferometer's dark port; (ii) a "variational-output"
interferometer (conceived in a different form by Vyatchanin, Matsko and
Zubova), in which homodyne detection with FD homodyne phase is performed on the
output light; and (iii) a "squeezed-variational interferometer" with squeezed
input and FD-homodyne output. It is shown that the FD squeezed-input light can
be produced by sending ordinary squeezed light through two successive
Fabry-Perot filter cavities before injection into the interferometer, and
FD-homodyne detection can be achieved by sending the output light through two
filter cavities before ordinary homodyne detection. With anticipated technology
and with laser powers comparable to that planned for LIGO-II, these
interferometers can beat the amplitude SQL by factors in the range from 3 to 5,
corresponding to event rate increases between ~30 and ~100 over the rate for a
SQL-limited interferometer.

</DOC>
<DOC>
<DOCNO> 120093 </DOCNO>
On the Mass Profile of Galaxy Cluster CL 0024+1654 Inferred from Strong


  Observations of a flat density profile in the cores of dark-matter-dominated
halos on the two extremes of mass for virialized objects in the universe, dwarf
galaxies and galaxy clusters, present a serious challenge to the current
standard theory of structure formation involving Cold Dark Matter (CDM). By
contrast, N-body simulations of halo formation in the latter indicate density
profiles which are singular and steeply rising towards the center. A
flat-density core on the cluster scale is indicated by gravitational lensing
observations, most significantly by the strong-lensing measurements of CL
0024+1654 by the Hubble Space Telescope. A recent re-analysis of this cluster
has suggested that a uniform-density core is not demanded by the data, thereby
eliminating a significant piece of the conflict between the observations and
the CDM theoretical predictions. We show here, however, that the singular mass
profile which that analysis reports as consistent with the lensing measurements
of CL 0024+1654 implies a velocity dispersion which is much higher than the
measured value for this cluster.

</DOC>
<DOC>
<DOCNO> 12733 </DOCNO>
Inhomogeneous relaxation in vibrated granular media: consolidation waves


  We investigate the spatial dependence of the density of vibrated granular
beds, using simulations based on a hybrid Monte Carlo algorithm. We find that
the initial consolidation is typically inhmogeneous, both in the presence of a
constant shaking intensity and when the granular bed is submitted to `annealed
shaking'. We also present a theoretical model which explains such inhomogeneous
relaxation in terms of a `consolidation wave', in good qualitative agreement
with our simulations. Our results are also in qualitative agreement with recent
simulations.

</DOC>
<DOC>
<DOCNO> 83193 </DOCNO>
Sorting Integers on the AP1000


  Sorting is one of the classic problems of computer science. Whilst well
understood on sequential machines, the diversity of architectures amongst
parallel systems means that algorithms do not perform uniformly on all
platforms. This document describes the implementation of a radix based
algorithm for sorting positive integers on a Fujitsu AP1000 Supercomputer,
which was constructed as an entry in the Joint Symposium on Parallel Processing
(JSPP) 1994 Parallel Software Contest (PSC94). Brief consideration is also
given to a full radix sort conducted in parallel across the machine.

</DOC>
<DOC>
<DOCNO> 119117 </DOCNO>
Confusion errors in astrometry and counterpart association


  In very crowded fields, the modulation of the background by the sea of
unresolved faint sources induces centroid shifts. The errors increase with the
number of sources per beam. Even the most optimistic simulations of imaging
data show that position errors can become severe (on the order of the beam
size) at flux levels at which images contain 1/50 to 1/15 sources per beam,
depending on the slope of the number-flux relation $d\log N/d\log S$. These
problems are expected to be significant for recent observations of faint
submillimeter sources and may be the reason that some sources appear to lack
optical counterparts.

</DOC>
<DOC>
<DOCNO> 119330 </DOCNO>
Mapping the X-ray Emitting Ejecta in Cassiopeia A with Chandra


  We present X-ray emission line equivalent width images of the bright Galactic
supernova remnant Cassiopeia A for the elements Si, S, Ar, Ca, and Fe using a
50,000 s observation with the Advanced CCD Imaging Spectrometer on the Chandra
X-ray Observatory. The images essentially identify the bulk of detectable
ejecta of these elements over a wide range of surface brightness, and show
morphologies distinctly different from that of the broadband X-ray emission and
of the 4-6 keV continuum emission. The Si, S, Ar, and Ca maps, while different
in turn from those of Fe, show that these X-ray emitting ejecta are distributed
similarly to the fast optical ejecta knots, and clearly delineate the X-ray
counterpart of the northeast optical jet. Low surface brightness regions just
outside the bright shell in the north and west are also shown to have strong
line emission. The strong Fe emission is exterior to that of other elements in
the east, as previously noted, but is generally coincident elsewhere. The
projected interior has relatively little emission traced by high line
equivalent widths.

</DOC>
<DOC>
<DOCNO> 7840 </DOCNO>
Anomalous Transmission in a Hierarchical Lattice


  We present an analytical method of studying "extended" electronic eigenstates
of a diamond hierarchical lattice, which may be taken as the simplest of the
hierarchical models recently proposed for stretched polymers. We use intuitive
arguments and a renormalization-group method to determine the distribution of
amplitudes of the wave functions corresponding to some of these "extended"
eigenstates. An exact analysis of the end-to-end transmission property of
arbitrarily large finite lattices reveals an anomalous behavoiur. It is seen
that while for a special value of the energy the lattice, however large,
becomes completely transparent to an incoming electron, for the other energy
eigenvalues the transmission decreases with system size. For one such energy
eigenvalue we analytically obtain the precise scaling form of the transmission
coefficient. The same method can easily be adopted for other energies.

</DOC>
<DOC>
<DOCNO> 119142 </DOCNO>
The gamma Velorum binary system. II. WR stellar parameters and the


  In this paper we derive stellar parameters for the Wolf-Rayet star in the
gamma Velorum binary system (WR11), from a detailed non-LTE model of its
optical and infrared spectra. Compared to the study of Schaerer et al., the
parameters of the WC8 star are revised to a hotter effective temperature
(Teff~57kK),a higher luminosity (log(L/Lsun = 5.00), and a lower mass loss rate
(log(Mdot / Msun/yr) = -5.0 - using a 10% clumping filling factor). These
changes lead to a significant decrease in wind efficiency number, from 144 to
7, so that the driving mechanism of the wind of this WR star may be simply
radiation pressure on lines. The derived spectroscopic luminosity is found to
be 40% lower than that derived by De Marco & Schmutz through the
mass-luminosity relationship for WR stars (log(L/Lsun = 5.2). The paper
furthermore presents a comparison of the independently-developed modelling
programs, CMFGEN and ISA-Wind . Overall, there seems to be very reasonable
agreement between the derived parameters for WR11, except for the carbon
content, which is 2 times higher for CMFGEN (C/He=0.15 vs. 0.06, by number).The
comparison also confirms a disparity in the predicted flux at lambda<$400A,
found by Crowther et al., which will have effects on several nebular line
strengths.
  The paper also presents the first independent check of the photon loss
mechanism proposed by Schmutz. We conclude that, not only is it important to
include very many lines to realistically model line blanketing, but in
particular those ones that critically interact with strong resonance lines
(e.g. HeII lambda303.78). The inclusion of these latter lines may significantly
alter the wind ionization structure.

</DOC>
<DOC>
<DOCNO> 99960 </DOCNO>
On the Law of Addition of Random Matrices


  Normalized eigenvalue counting measure of the sum of two Hermitian (or real
symmetric) matrices $A_{n}$ and $B_{n}$ rotated independently with respect to
each other by the random unitary (or orthogonal) Haar distributed matrix
$U_{n}$ (i.e. $A_{n}+U_{n}^{\ast}B_{n}U_{n}$) is studied in the limit of large
matrix order $n$. Convergence in probability to a limiting nonrandom measure is
established. A functional equation for the Stieltjes transform of the limiting
measure in terms of limiting eigenvalue measures of $A_{n}$ and $B_{n}$ is
obtained and studied.
  Keywords: random matrices, eigenvalue distribution

</DOC>
<DOC>
<DOCNO> 72310 </DOCNO>
Relativistic theories of interacting fields and fluids


  We investigate divergence-type theories (DTT) describing the dissipative
interaction between a field and a fluid. We look for theories which, under
equilibrium conditions, reduce to the theory of a Klein-Gordon scalar field and
a perfect fluid. We show that the requirements of causality and positivity of
entropy production put non-trivial constarints to the structure of the
interaction terms. These theories provide a basis for the phenomonological
study of the reheating period.

</DOC>
<DOC>
<DOCNO> 8106 </DOCNO>
History dependence of peak effect in CeRu$_2$ and V$_3$Si: an analogy


  We present results of transport measurements showing distinct path dependence
of the electrical resistance in the superconducting vortex state of single
crystal samples of CeRu$_2$ and V$_3$Si. Resistance measured in the vortex
state of both the systems prepared by field cooling (FC), indicates a
relatively higher degree of disorder than when it is prepared by isothermal
variation of field. Small oscillations of magnetic field modify the resistance
in the FC state, highlighting the metastable nature of that state. An analogy
is drawn with the FC state of the random-field Ising systems.

</DOC>
<DOC>
<DOCNO> 69120 </DOCNO>
Masses of Heavy Hadrons


  An estimate has been made of the masses of heavy hadrons in nonrelativistic
quark model, which includes spin and flavor-dependent hyperfine splitting for
two quarks. The effect of variation of the wavefunction value at origin and the
strong coupling constant, with flavor, has also been included in calculating
the mass values.

</DOC>
<DOC>
<DOCNO> 84307 </DOCNO>
Localization of gravitational energy in ENU model and its consequences


  The contribution provides the starting points and background of the model of
Expansive Nondecelerative Universe (ENU), manifests the advantage of
exploitation of Vaidya metrics for the localization and quantization of
gravitational energy, and offers four examples of application of the ENU model,
namely energy of cosmic background radiation, energy of Z and W bosons acting
in weak interactions, hyperfine splitting observed for hydrogen 1s orbital.
Moreover, time evolution of vacuum permitivity and permeability is predicted.%

</DOC>
<DOC>
<DOCNO> 13763 </DOCNO>
On the constitution of sodium at higher densities


  Using density functional theory the atomic and electronic structure of sodium
are predicted to depart substantially from those expected of simple metals for
$r_s <$ 2.48 ($p > 130$ GPa). Newly-predicted phases include those with low
structural symmetry, semi-metallic electronic properties (including zero-gap
semiconducting limiting behavior), unconventional valence charge density
distributions, and even those that raise the possibility of superconductivity,
all at currently achievable pressures. Important differences emerge between
sodium and lithium at high densities, and these are attributable to
corresponding differences in their respective cores.

</DOC>
<DOC>
<DOCNO> 117677 </DOCNO>
Starquake-Induced Glitches in Pulsars


  The neutron star crust is rigid material floating on a neutron-proton liquid
core. As the star's spin rate slows, the changing stellar shape stresses the
crust and causes fractures. These starquakes may trigger pulsar glitches as
well as the jumps in spin-down rate that are observed to persist after some
glitches. Earlier studies found that starquakes in spinning-down neutron stars
push matter toward the magnetic poles, causing temporary misalignment of the
star's spin and angular momentum. After the star relaxes to a new equilibrium
orientation, the magnetic poles are closer to the equator, and the magnetic
braking torque is increased. The magnitude and sign of the predicted torque
changes are in agreement with the observed persistent spin-down offsets. Here
we examine the relaxation processes by which the new equilibrium orientation is
reached. We find that the neutron superfluid in the inner crust slows as the
star's spin realigns with the angular momentum, causing the crust to spin more
rapidly. For plausible parameters the time scale and the magnitude of the
crust's spin up agree with the giant glitches in the Vela and other pulsars.

</DOC>
<DOC>
<DOCNO> 122447 </DOCNO>
Presupernova Evolution with Improved Rates for Weak Interactions


  Recent shell-model calculations of weak-interaction rates for nuclei in the
mass range A = 45 - 65 have resulted in substantial revisions to the hitherto
standard set of Fuller, Fowler, & Newman (FFN). In particular, key
electron-capture rates, such as that for Co60 are much smaller. We consider
here the effects of these revised rates on the presupernova (post-oxygen
burning) evolution of massive stars in the mass range 11 to 40 M_sun. Moreover,
we include, for the first time in models by our group, the effects of modern
rates for beta-decay in addition to electron capture and positron emission.
Values for the central electron mole number at the time of iron core collapse
in the new models are typically larger, by delta Y_e = 0.005 to 0.015, than
those of Woosley & Weaver 1995, with a tendency for the more massive models to
display larger differences. About half of this change is a consequence of
including beta-decay; the other half, result of the smaller rates for electron
capture. Unlike what might be expected solely on basis of the larger Y_e's, the
new iron core masses are systematically smaller owing to a decrease in the
entropy in the outer iron core. The changes in iron core mass range from zero
to 0.1 M_sun. We also observe, as predicted by Aufderheide et al. (1994), a
tendency towards beta-equilibrium just prior to the collapse of the core, and
the subsequent loss of that equilibrium as core collapse proceeds. We discuss
the key weak reaction rates, both beta-decay and electron-capture, responsible
for the evolution of Y_e and make suggestions for future measurements.

</DOC>
<DOC>
<DOCNO> 152611 </DOCNO>
Brane-Antibrane Action from Boundary String Field Theory


  In this paper we give the boundary string field theory description of
brane-antibrane systems. From the world-sheet action of brane-antibrane systems
we obtain the tachyon potential and discuss the tachyon condensation exactly.
We also find the world-volume action including the gauge fields. Moreover we
determine RR-couplings exactly for non-BPS branes and brane-antibranes. These
couplings are written by superconnections and correspond to K^1(M) and K^0(M)
for the non-BPS branes and brane-antibranes, respectively. We also show that
Myers terms appear if we include the transverse scalars in the boundary sigma
model action.

</DOC>
<DOC>
<DOCNO> 12682 </DOCNO>
Towards Better Integrators for Dissipative Particle Dynamics Simulations


  Coarse-grained models that preserve hydrodynamics provide a natural approach
to study collective properties of soft-matter systems. Here, we demonstrate
that commonly used integration schemes in dissipative particle dynamics give
rise to pronounced artifacts in physical quantities such as the compressibility
and the diffusion coefficient. We assess the quality of these integration
schemes, including variants based on a recently suggested self-consistent
approach, and examine their relative performance. Implications of
integrator-induced effects are discussed.

</DOC>
<DOC>
<DOCNO> 121898 </DOCNO>
Parameterisation of Galaxy Spectra in the 2dF Galaxy Redshift Survey


  The 2dF Galaxy Redshift Survey has already yielded over 130,000 galaxy
spectra (out of the planned 250,000). We present a method for the
parameterisation of galaxy spectra in the 2dF and other large redshift surveys
using a new continuous parameter eta=0.44pc1 - pc2, based on a Principal
Components Analysis (where pc1 and pc2 are the projections onto the first and
second principal components respectively). This parameter is designed to be
robust to instrumental uncertainties and it represents the absorption/emission
strength of a galaxy.

</DOC>
<DOC>
<DOCNO> 116896 </DOCNO>
Tests of the CERN Proton Linac Performance for LHC-Type Beams


  As the pre-injector of the LHC injector chain, the proton linac at CERN is
required to provide a high-intensity (180mA) beam to the Proton Synchrotron
Booster. The results of measurements at this intensity will be presented.
Furthermore, the linac is now equipped with bunch shape monitors from INR,
Moscow, which have allowed the comparison of the Alvarez tank RF settings with
simulations.

</DOC>
<DOC>
<DOCNO> 151227 </DOCNO>
Monopole in the dilatonic gauge field theory


  A numerical study of coupled to the dilaton field, static, spherically
symmetric monopole solutions inspired by the Kaluza-Klein theory with large
extra dimensions are presented. The generalized Prasad-Sommerfield solution is
obtained. We show that monopole may have also the dilaton cloud configurations.

</DOC>
<DOC>
<DOCNO> 72023 </DOCNO>
Testing Scalar-Sector CP Violation in Top-Quark Production and Decay at


  We consider a general two-Higgs-doublet model with CP violation in the scalar
sector. Three neutral Higgs fields of the model all mix and the resulting
physical Higgs bosons have no definite CP properties. That leads, at the
one-loop level of the perturbation expansion, to CP-violating form factors for
gamma-t-tbar, Z-t-tbar and W-t-b interaction vertices. We discuss asymmetries
sensitive to CP violation induced by the form factors for the process e^+ e^-
-> t tbar -> l^\pm ... and e^+ e^- -> t tbar -> b/bbar ... at future linear e+
e- colliders.

</DOC>
<DOC>
<DOCNO> 170594 </DOCNO>
On the equivalence of the Langevin and auxiliary field quantization


  Recently two methods have been developed for the quantization of the
electromagnetic field in general dispersing and absorbing linear dielectrics.
The first is based upon the introduction of a quantum Langevin current in
Maxwell's equations [T. Gruner and D.-G. Welsch, Phys. Rev. A 53, 1818 (1996);
Ho Trung Dung, L. Kn\"{o}ll, and D.-G. Welsch, Phys. Rev. A 57, 3931 (1998); S.
Scheel, L. Kn\"{o}ll, and D.-G. Welsch, Phys. Rev. A 58, 700 (1998)], whereas
the second makes use of a set of auxiliary fields, followed by a canonical
quantization procedure [A. Tip, Phys. Rev. A 57, 4818 (1998)]. We show that
both approaches are equivalent.

</DOC>
<DOC>
<DOCNO> 7705 </DOCNO>
Electron Localization at Metal Surfaces


  We investigate some surfaces of a paradigmatic sp bonded metal--namely,
Al(110), Al(100), and Al(111)--by means of the "electron localization function"
(ELF), implemented in a first-principle pseudopotential framework. ELF is a
ground-state property which discriminates in a very sharp, quantitative, way
between different kinds of bonding. ELF shows that in the bulk of Al the
electron distribution is essentially jelliumlike, while what happens at the
surface strongly depends on packing. At the least packed surface, Al(110), ELF
indicates a free-atom nature of the electron distribution in the outer region.
The most packed surface, Al(111), is instead at the opposite end, and can be
regarded as a jellium surface weakly perturbed by the presence of the ionic
cores.

</DOC>
<DOC>
<DOCNO> 151843 </DOCNO>
Holography and the C-Theorem


  We review the geometric definition of C-function in the context of field
theories that admit a holographic gravity dual.

</DOC>
<DOC>
<DOCNO> 68536 </DOCNO>
The Wh decay channel as a probe of charged Higgs boson production at the


  We analyse the chances of detecting charged Higgs bosons of the Minimal
Supersymmetric Standard Model (MSSM) at the Large Hadron Collider (LHC) in the
$W^\pm h$ mode, followed by the dominant decay of the lightest Higgs scalar,
$h\to b\bar b$. If the actual value of $M_h$ is already known, this channel
offers possibly the optimal final state kinematics for charged Higgs discovery,
thanks to the narrow resonances appearing around the $W^\pm$ and $h$ masses.
Besides, within the MSSM, the $H^\pm\to W^\pm h$ decay rate is significant for
not too large $\tan\beta$ values, thus offering the possibility of accessing a
region of MSSM parameter space left uncovered by other search channels. We
consider both strong (QCD) and electroweak (EW) `irreducible' backgrounds in
the $3b$-tagged channel to the $gg\to t\bar bH^-$ production process that had
not been taken into account in previous analyses. After a series of kinematic
cuts, the largest of these processes is $t\bar bW^\pm h$ production in the
continuum. However, for optimum $\tan\beta$, i.e., between 2 and 3, the charged
Higgs boson signal overcomes this background and a narrow discovery region
survives around $M_{H^\pm}\approx200$ GeV

</DOC>
<DOC>
<DOCNO> 9227 </DOCNO>
On the criterion for Bose-Einstein condensation for particles in traps


  We consider the criterion for Bose condensation for particles in a harmonic
trap. For a fixed angular momentum, the lowest energy state for a cloud of
bosons with attractive interactions is the ground state of the cloud with all
the angular momentum in the center-of-mass motion, and the one-particle reduced
density matrix generally does not have a single large eigenvalue, but a number
of them, suggesting that the state is an example of a fragmented condensate
(Wilkin, Gunn, and Smith, Phys. Rev. Lett. 80, 2265 (1998)). We show that a
convenient way to describe correlations in the system is by defining an
internal one-particle reduced density matrix, in which the center-of-mass
motion is eliminated, and that this has a single eigenvalue equal to the number
of particles for the problem considered here. Our considerations indicate that
care is necessary in formulating a criterion for Bose-Einstein condensation.

</DOC>
<DOC>
<DOCNO> 121949 </DOCNO>
Astronomical Constraints on the Cosmic Evolution of the Fine Structure


  We present measurements of absorption by the 21cm hyperfine transition of
neutral hydrogen toward radio sources at substantial look-back times. These
data are used in combination with observations of rotational transitions of
common interstellar molecules, to set limits on the evolution of the fine
structure constant: (dot alpha)/alpha < 3.5e-15/yr to a look-back time of 4.8
Gyr. The neutral hydrogen observations employed Very Long Baseline
Interferometry in order to mitigate the substantial uncertainty arising from
the fact that observations at very different wavelengths may probe different
lines-of-site due to frequency dependent structure of the background source. We
discuss the implication of these results on theories unifying natural forces
based on compact quantum dimensions. In the context of string theory, the limit
on the secular evolution of the scale factor of these compact dimensions, R, is
(dot R)/R < 1e-15/yr. Including terrestrial and other astronomical measurements
places limits (2sigma) on slow oscillations of R from the present to the epoch
of cosmic nucleosynthesis, just seconds after the big bang, of (Delta R)/R <
1e-5.

</DOC>
<DOC>
<DOCNO> 119870 </DOCNO>
Six-body calculation of the alpha-deuteron radiative capture cross


  We have computed the cross section for the process d + alpha -> 6Li + gamma
at the low energies relevant for primordial nucleosynthesis and comparison with
laboratory data. The final state is a six-body wave function generated by the
variational Monte Carlo method from the Argonne v_18 and Urbana IX potentials,
including improved treatment of large-particle-separation behavior. The initial
state is built up from the alpha-particle and deuteron ground-state solutions
for these potentials, with phenomenological descriptions of scattering and
cluster distortions. The dominant E2 cross section is in reasonable agreement
with the laboratory data. Including center-of-energy and other small
corrections, we obtain an E1 contribution which is larger than the measured
contribution at 2 MeV by a factor of 7. We calculate explicitly the
impulse-approximation M1 contribution, which is expected to be very small, and
obtain a result consistent with zero. We find little reason to suspect that the
cross section is large enough to produce significant 6Li in the big bang.

</DOC>
<DOC>
<DOCNO> 69930 </DOCNO>
The radion contribution to the weak mixing angle


  In the Randall-Sundrum (RS) compactification, the gap between two branes is
stabilized by the vacuum expectation value of a scalar field called {\it
radion}, $\phi$. This radion behaves like a weak interaction singlet scalar
field, coupling to matter through the trace of the energy momentum tensor. We
find that it can induce a sizable correction to the weak mixing angle if the
vacuum expectation value and the mass of the radion is around TeV. We also
comment on the contribution to the $K_L-K_S$ mass difference and to
$(g-2)_\mu$.

</DOC>
<DOC>
<DOCNO> 8331 </DOCNO>
Violation of ensemble equivalence in the antiferromagnetic mean-field XY


  It is well known that long-range interactions pose serious problems for the
formulation of statistical mechanics. We show in this paper that ensemble
equivalence is violated in a simple mean-field model of N fully coupled
classical rotators with repulsive interaction (antiferromagnetic XY model).
While in the canonical ensemble the rotators are randomly dispersed over all
angles, in the microcanonical ensemble a bi-cluster of rotators separated by
angle $\pi$, forms in the low energy limit. We attribute this behavior to the
extreme degeneracy of the ground state: only one harmonic mode is present,
together with N-1 zero modes. We obtain empirically an analytical formula for
the probability density function for the angle made by the rotator, which
compares extremely well with numerical data and should become exact in the zero
energy limit. At low energy, in the presence of the bi-cluster, an extensive
amount of energy is located in the single harmonic mode, with the result that
the energy temperature relation is modified. Although still linear, $T = \alpha
U$, it has the slope $\alpha \approx 1.3$, instead of the canonical value
$\alpha =2$.

</DOC>
<DOC>
<DOCNO> 151029 </DOCNO>
D2-branes in B fields


  This note focuses on the coupling of a type IIA D2-brane to a background B
field. It is shown that the D0-brane charge arising from the integral over the
D2-brane of the pullback of the B field is cancelled by bulk contributions, for
a compact D2-brane wrapping a homotopically trivial cycle in space-time. In
M-theory this cancellation is a straightforward consequence of momentum
conservation. This result resolves a puzzle recently posed by Bachas, Douglas
and Schweigert related to the quantization of R-R charges on stable spherical
D2-branes on the group manifold SU(2).

</DOC>
<DOC>
<DOCNO> 85403 </DOCNO>
Relativity and Nonlocality


  The basic physical structure of the relativistic theory of gravitation is
discussed. The significant role that the Hypothesis of Locality plays in
relativity theory is elucidated via the phenomenon of spin-rotation coupling.
The limitations of this hypothesis are critically examined. A nonlocal theory
of accelerated observers is presented and some of its observational
consequences are described.

</DOC>
<DOC>
<DOCNO> 12344 </DOCNO>
Tradable Schemes


  In this article we present a new approach to the numerical valuation of
derivative securities. The method is based on our previous work where we
formulated the theory of pricing in terms of tradables. The basic idea is to
fit a finite difference scheme to exact solutions of the pricing PDE. This can
be done in a very elegant way, due to the fact that in our tradable based
formulation there appear no drift terms in the PDE. We construct a mixed scheme
based on this idea and apply it to price various types of arithmetic Asian
options, as well as plain vanilla options (both european and american style) on
stocks paying known cash dividends. We find prices which are accurate to $\sim
0.1%$ in about 10ms on a Pentium 233MHz computer and to $\sim 0.001%$ in a
second. The scheme can also be used for market conform pricing, by fitting it
to observed option prices.

</DOC>
<DOC>
<DOCNO> 150600 </DOCNO>
Dilatonic formulation for conducting cosmic string models


  It is shown how the the introduction of a suitably defined dilatonic
auxiliary field, $\Phi$ say, makes it possible for the non-linear Lagrangian
for a generic elastic string model, of the kind appropriate for representing
superconducting cosmic strings, to be converted into a standardised form as the
sum of a kinetic term that is just homogeneously quadratic in the relevant
scalar phase gradient (as in a simple linear model) together with a potential
energy term, $V$ say, that is specified as a generically non-linear function of
$\Phi$. The explicit form of this function is derived for various noteworthy
examples, of which the most memorable is that of the transonic string model, as
characterised by a given mass scale, $m$ say, for which this potential energy
density will be expressible in terms of the zero current limit value
$\Phi_{_0}$ of $\Phi$ by $ V= {1\over 2} m \big(\Phi_{_0}^{-2} \Phi^2+
\Phi_{_0}^{2} \Phi^{-2} \big)$.

</DOC>
<DOC>
<DOCNO> 70253 </DOCNO>
Nonperturbative Techniques for QED Bound States


  Advantages of using a low-energy effective theory to study bound state
properties are briefly discussed, and a nonperturbative implementation of such
an effective theory is described within the context of nonrelativistic quantum
mechanics. The hydrogen atom, in the approximation of a structureless,
infinite-mass nucleus, but with the leading relativistic and radiative
corrections included, is used to demonstrate the construction and solution of
the effective theory. The resulting Hamiltonian incorporates a finite
ultraviolet cutoff and can be solved nonperturbatively. An appendix lists
explicit formulae for the various matrix elements necessary to diagonalize the
Hamiltonian using gaussian basis sets.

</DOC>
<DOC>
<DOCNO> 99872 </DOCNO>
Projectively Quantization Map


  Let M be a manifold endowed with a symmetric affine connection $\Gamma.$ The
aim of this paper is to describe a quantization map between the space of
second-order polynomials on the cotangent bundle T^{*} M and the space of
second-order linear differential operators, both viewed as modules over the
group of diffeomorphisms and the Lie algebra of vector fields on M. This map is
an isomorphism, for almost all values of certain constants, and it depend only
on the projective class of the affine connection $\Gamma.$

</DOC>
<DOC>
<DOCNO> 122751 </DOCNO>
The population of close double white dwarfs in the Galaxy


  We present a new model for the Galactic population of close double white
dwarfs. The model accounts for the suggestion of the avoidance of a substantial
spiral-in during mass transfer between a giant and a main-sequence star of
comparable mass and for detailed cooling models. It agrees well with the
observations of the local sample of white dwarfs if the initial binary fraction
is close to 50% and an ad hoc assumption is made that white dwarfs with mass
less than about 0.3 solar mass cool faster than the models suggest. About 1000
white dwarfs brighter than V=15 have to be surveyed for detection of a pair
which has total mass greater than the Chandrasekhar mass and will merge within
10 Gyr.

</DOC>
<DOC>
<DOCNO> 68771 </DOCNO>
Quarkonium Production through Hard Comover Scattering. II


  We extend to large transverse momentum pt an approach to quarkonium
hadroproduction previously suggested for low pt. The dynamics involves a
perturbative rescattering of the heavy quark pair off a comoving color field
which originates from gluon radiation prior to the heavy quark production
vertex. Assuming simple properties of the comoving field we find the
rescattering scenario to be in reasonable agreement with data. At large pt,
psi' is predicted to be unpolarized, and chi1 production is favoured compared
to chi2. We predict the chi1 polarization to be transverse at low pt, and to
get a longitudinal component at large pt.

</DOC>
<DOC>
<DOCNO> 71708 </DOCNO>
Numerical simulations of fragmentation of the Affleck-Dine condensate


  We present numerical simulations of fragmentation of the Affleck-Dine
condensate in two spatial dimensions. We argue analytically that the final
state should consist of both Q-balls and anti-Q-balls in a state of maximum
entropy, with most of the balls small and relativistic. Such a behaviour is
found in simulations on a 100x100 lattice with cosmologically realistic
parameter values. During fragmentation process, we observe filament-like
texture in the spatial distribution of charge. The total charge in Q-balls is
found to be almost equal to the charge in anti-Q-balls and typically orders of
magnitude larger than charge asymmetry. Analytical considerations indicate
that, apart from geometrical factors, the results of the simulated two
dimensional case should apply also to the fully realistic three dimensional
case.

</DOC>
<DOC>
<DOCNO> 117492 </DOCNO>
2 micron Spectroscopy within 0.3 arcseconds of SgrA*


  We present moderate (R~$\approx$~2,700) and high resolution
(R~$\approx$~22,000) 2.0$-$2.4 \micron\ spectroscopy of the central 0.1 square
arcseconds of the Galaxy obtained with NIRSPEC, the facility near-infrared
spectrometer for the Keck II telescope. The composite spectra do not have any
features attributable to the brightest stars in the central cluster, i.e.\
after background subtraction, W$_{\rm ^{12}CO(2-0)}$~$<$~2~\AA. This stringent
limit leads us to conclude that the majority, if not all, of the stars are
hotter than typical red giants. Coupled with previously reported photometry, we
conclude that the sources are likely OB main sequence stars. In addition, the
continuum slope in the composite spectrum is bluer than that of a red giant and
is similar to that of the nearby hot star, IRS16NW. It is unlikely that they
are late-type giants stripped of their outer envelopes because such sources
would be much fainter than those observed. Given their inferred youth
($\tau_{\rm age}$~$<$~20~\Myr), we suggest the possibility that the stars have
formed within 0.1 pc of the supermassive black hole. We find a newly-identified
broad-line component (V$_{\rm FWHM}$ $\approx$ 1,000 \kms) to the 2.2178
\micron\ [\ion{Fe}{3}] line located within a few arcseconds of Sgr~A$^*$. A
similar component is not seen in the Br-$\gamma$ emission.

</DOC>
<DOC>
<DOCNO> 83175 </DOCNO>
Variable Word Rate N-grams


  The rate of occurrence of words is not uniform but varies from document to
document. Despite this observation, parameters for conventional n-gram language
models are usually derived using the assumption of a constant word rate. In
this paper we investigate the use of variable word rate assumption, modelled by
a Poisson distribution or a continuous mixture of Poissons. We present an
approach to estimating the relative frequencies of words or n-grams taking
prior information of their occurrences into account. Discounting and smoothing
schemes are also considered. Using the Broadcast News task, the approach
demonstrates a reduction of perplexity up to 10%.

</DOC>
<DOC>
<DOCNO> 67912 </DOCNO>
Decompactification of space or time in large N QCD_2


  QCD_2 with fundamental quarks on a cylinder is solved to leading order in the
1/N expansion, including the zero mode gluons. As a result of the
non-perturbative dynamics of these gauge degrees of freedom, the compact
space-time direction gets effectively decompactified. In a thermodynamic
interpretation, this implies that there is no pressure of order N and that the
chiral condensate of order N is temperature independent. These findings are
consistent with confinement of quarks, rule out both chiral and deconfining
phase transitions in the finite temperature 't Hooft model, and help to resolve
some controversial issues in the literature

</DOC>
<DOC>
<DOCNO> 12514 </DOCNO>
Specific heat of (Y,Lu)Ni2B2C in the mixed state


  The temperature and magnetic field dependences of the electronic specific
heat in the superconducting mixed state as well as the upper critical field
have been measured on a (Y,Lu)Ni2B2C series to study the influence of disorder.
The electronic specific heat in the vortex state shows deviations from the
usual gamma(H) proportional to H-law for conventional superconductors for all
samples resulting in a disorder dependent negative curvature of gamma
proportional to H sup(1-beta). For samples with disorder at the R site beta and
the positive curvature exponent alpha of H sub(c2) are reduced but alpha, beta
remain always positive, as distinct from much stronger disorder due to Pt
substions at the Ni site where alpha, beta rapidly tend to 0. Alpha shows a
minimum at equal Y and Lu concentration. H sub(c2)(00, T sub(c), the curvatures
of H sub(c2) and gamma(h), as well as the normal state Sommerfeld constant
gamma sub(N) are reduced similarly.

</DOC>
<DOC>
<DOCNO> 121086 </DOCNO>
The Supergiant Shell LMC2: II. Physical Properties of the 10^6 K Gas


  LMC2 has the highest X-ray surface brightness of all know supergiant shells
in the Large Magellanic Cloud (LMC). The X-ray emission peaks within the
ionized filaments that define the shell boundary, but also extends beyond the
southern border of LMC2 as an X-ray bright spur. ROSAT HRI images reveal the
X-ray emission from LMC2 and the spur to be truly diffuse, indicating a hot
plasma origin. We have obtained ROSAT PSPC and ASCA SIS spectra to study the
physical conditions of the hot gas interior to LMC2 and the spur. Raymond-Smith
thermal plasma model fits to the X-ray spectra, constrained by HI 21-cm
emission-line measurements of the column density, show the plasma temperature
of the hot gas interior of LMC2 to be kT = 0.1 - 0.7 keV and of the spur to be
kT = 0.1 - 0.5 keV. We have compared the physical conditions of the hot gas
interior to LMC2 with those of other supergiant shells, superbubbles, and
supernova remnants (SNRs) in the LMC. We find that our derived electron
densities for the hot gas inside LMC2 is higher than the value determined for
the supergiant shell LMC4, comparable to the value determined for the
superbubble N11, and lower than the values determined for the superbubble N44
and a number of SNRs.

</DOC>
<DOC>
<DOCNO> 101790 </DOCNO>
Conjugated filter approach for solving Burgers' equation with high


  We propose a conjugated filter oscillation reduction scheme for solving
Burgers' equation with high Reynolds numbers. Computational accuracy is tested
at a moderately high Reynolds number for which analytical solution is
available. Numerical results at extremely high Reynolds numbers indicate that
the proposed scheme is efficient, robust and reliable for shock capturing.

</DOC>
<DOC>
<DOCNO> 100931 </DOCNO>
Modular categories of types B,C and D


  We construct four series of modular categories from the two-variable Kauffman
polynomial, without use of the representation theory of quantum groups at roots
of unity. The specializations of this polynomial corresponding to quantum
groups of types B, C and D produce series of pre-modular categories. One of
them turns out to be modular and three others satisfy Brugui\`eres'
modularization criterion. For these four series we compute the Verlinde
formulas, and discuss spin and cohomological refinements.

</DOC>
<DOC>
<DOCNO> 118199 </DOCNO>
Rotations and Abundances of Blue Horizontal-Branch Stars in Globular


  High-resolution optical spectra of eighteen blue horizontal-branch (BHB)
stars in the globular cluster M15 indicate that their stellar rotation rates
and photospheric compositions vary strongly as a function of effective
temperature. Among the cooler stars in the sample, at Teff ~ 8500 K, metal
abundances are in rough agreement with the canonical cluster metallicity, and
the v sin i rotations appear to have a bimodal distribution, with eight stars
at v sin i < 15 km/s and two stars at v sin i ~ 35 km/s. Most of the stars at
Teff > 10000 K, however, are slowly rotating, v sin i < 7 km/s, and their iron
and titanium are enhanced by a factor of 300 to solar abundance levels.
Magnesium maintains a nearly constant abundance over the entire range of Teff,
and helium is depleted by factors of 10 to 30 in three of the hotter stars.
Diffusion effects in the stellar atmospheres are the most likely explanation
for these large differences in composition. Our results are qualitatively very
similar to those previously reported for M13 and NGC 6752, but with even larger
enhancement amplitudes, presumably due to the increased efficiency of radiative
levitation at lower intrinsic [Fe/H]. We also see evidence for faster stellar
rotation explicitly preventing the onset of the diffusion mechanisms among a
subset of the hotter stars.

</DOC>
<DOC>
<DOCNO> 40383 </DOCNO>
Nuclear shadowing in polarized DIS on ^6LiD at small x and its effect on


  We consider the effect of nuclear shadowing in polarized deep inelastic
scattering (DIS) on ^6LiD at small Bjorken x and its relevance to the
extraction of the deuteron spin structure function g_{1}^{d}(x,Q^2). Using
models, which describe nuclear shadowing in unpolarized DIS, we demonstrate
that the nuclear shadowing correction to g_{1}^{d}(x,Q^2) is significant.

</DOC>
<DOC>
<DOCNO> 72139 </DOCNO>
Absence of higher order corrections to the non-Abelian topological mass


  We study the Yang-Mills-Chern-Simons theory systematically in an effort to
generalize the Coleman-Hill result to the non-Abelian case. We show that, while
the Chern-Simons coefficient is in general gauge dependent in a non-Abelian
theory, it takes on a physical meaning in the axial gauge. Using the
non-Abelian Ward identities as well as the analyticity of the amplitudes in the
momentum variables, we show that, in the axial gauge, the Chern-Simons
coefficient does not receive any quantum correction beyond one loop. This
allows us to deduce that the ratio ${4\pi m\over g^{2}}$ is unrenormalized, in
a non-Abelian theory, beyond one loop in any infrared safe gauge. This is the
appropriate generalization of the Coleman-Hill result to non-Abelian theories.
Various other interesting properties of the theory are also discussed.

</DOC>
<DOC>
<DOCNO> 70304 </DOCNO>
Multiplicity distributions of quark and gluon jets in QCD


  The solution of the equations for the generating functions of multiplicity
distributions of quark and gluon jets in higher order 3NLO perturbative QCD is
obtained. The non-perturbative effects are discussed as well. The results are
compared to recent experimental data on mean multiplicities, their ratio and
its slope, higher moments of the distributions.

</DOC>
<DOC>
<DOCNO> 152589 </DOCNO>
Scalar Casimir effect for D-dimensional spherically symmetric Robin


  The vacuum expectation values for the energy-momentum tensor of a massive
scalar field with general curvature coupling and obeying the Robin boundary
condition on spherically symmetric boundaries in D-dimensional space are
investigated. The expressions are derived for the regularized vacuum energy
density, radial and azimuthal stress components (i) inside and outside a single
spherical surface and (ii) in the intermediate region between two concentric
spheres. Regularization procedure is carried out by making use of the
generalized Abel-Plana formula for the series over zeros of cylinder functions.
Asymptotic behavior of the vacuum densities near the sphere and at large
distances is investigated. A decomposition of the Casimir energy into volumic
and surface parts is provided for both cases (i) and (ii). We show that the
mode sum energy, evaluated as a sum of the zero-point energies for each normal
mode of frequency, and the volume integral of the energy density in general are
different, and argue that this difference is due to the existence of an
additional surface energy contribution.

</DOC>
<DOC>
<DOCNO> 117434 </DOCNO>
BeppoSAX observations of the nearby low-mass X-ray binary and fast


  SAX J1819.3-2525 is a nearby X-ray transient which exhibited a fast and large
X-ray outburst on Sep. 15, 1999 (Smith et al. 1999). The Wide Field Cameras and
the Narrow Field Instruments (NFI) on board BeppoSAX observed SAX J1819.3-2525
at various stages of its activity before that, in the spring and fall of 1999.
The fluxes range between 0.012 and 0.3 Crab units (2-10 keV). The NFI
observation is unique because it is the longest semi-continuous observation of
SAX J1819.3-2525 so far, and it offers a study of the spectrum at a relatively
high resolution of 8% full width at half maximum at 6 keV. We discuss the
observations with emphasis on the X-ray spectrum. A strong Fe-K emission line
was detected in SAX J1819.3-2525 with an equivalent width between 0.3 and 1
keV. The line energy is up to 6.85 +/- 0.02 keV and suggests the presence of
highly ionized iron. We identify this as fluorescent emission from a
photo-ionized plasma. The continuum spectrum is typical for a low-mass X-ray
binary in which emission from an accretion disk corona plays an important role.
There is no sign of an eclipse or periodic signal due to the binary orbit in
this exposure, despite the fact that the twin jets seen at radio wavelengths
suggest a high inclination angle.

</DOC>
<DOC>
<DOCNO> 71892 </DOCNO>
Primordial Nucleosynthesis, Cosmic Microwave Background and Neutrinos


  We report the results of a recent likelihood analysis combining the
primordial nucleosynthesis and the BOOMERanG and MAXIMA-1 data on cosmic
microwave background radiation anisotropies. We discuss the possible
implications for relic neutrino background of a high value for the baryonic
matter content of the universe, larger than what is expected in a standard
nucleosynthesis scenario.

</DOC>
<DOC>
<DOCNO> 119094 </DOCNO>
The Evolution of 3He, 4He and D in the Galaxy


  In this work we present the predictions of a modified version of the
``two-infall model'' (Chiappini et al. 1997) for the evolution of 3He, 4He and
D in the solar vicinity, as well as their distributions along the Galactic
disk. In particular, we show that when allowing for extra-mixing process in low
mass stars, as predicted by Charbonnel and do Nascimento (1998), a long
standing problem in chemical evolution is solved, namely: the overproduction of
3He by the chemical evolution models as compared to the observed values in the
sun and in the interstellar medium. Moreover, we show that chemical evolution
models can constrain the primordial value of the deuterium abundance and that a
value of primordial D/H < 3 x 10(-5) is suggested by the present model.
Finally, adopting the primordial 4He abundance suggested by Viegas et al.
(1999), we obtain a value for dY/dZ around 2 and a better agreement with the
solar He abundance.

</DOC>
<DOC>
<DOCNO> 13376 </DOCNO>
Vortex Matter Transition in Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+y}$ under


  Vortex phase diagram under tilted fields from the $c$ axis in
Bi${}_2$Sr${}_2$CaCu${}_2$O${}_{8+y}$ is studied by local magnetization
hysteresis measurements using Hall probes. When the field is applied at large
angles from the $c$ axis, an anomaly ($H_p^\ast$) other than the well-known
peak effect ($H_p$) are found at fields below $H_p$. The angular dependence of
the field $H_p^\ast$ is nonmonotonic and clearly different from that of $H_p$
and depends on the oxygen content of the crystal. The results suggest existence
of a vortex matter transition under tilted fields. Possible mechanisms of the
transition are discussed.

</DOC>
<DOC>
<DOCNO> 13166 </DOCNO>
On direction of spontaneous magnetization in a "cubic" ferromagnet


  The magnetic properties of anisotropic films have been studied using
3D-neutron polarization analysis. The experimental facts refer to essential
distinction of the sample states, magnetized in opposite directions. For an
explanation of asymmetrical effects the model is offered, in which the
fundamental theoretical principles of structural phase transitions are used.

</DOC>
<DOC>
<DOCNO> 152508 </DOCNO>
D-branes in Massive IIA and Solitons in Chern-Simons Theory


  We investigate D2-branes and D4-branes parallel to D8-branes. The low energy
world volume theory on the branes is non-supersymmetric Chern-Simons theory. We
identify the fundamental strings as the anyons of the 2+1 Chern-Simons theory
and the D0-branes as solitons. The Chern-Simons theory with a boundary is
modeled using NS 5-branes with ending D6-branes. The brane set-up provides for
a graphical description of anomaly inflow. We also model the 4+1 Chern-Simons
theory using branes and conjecture that D4-branes with a boundary describes a
supersymmetric version of Kaplan's theory of chiral fermions.

</DOC>
<DOC>
<DOCNO> 152007 </DOCNO>
Gauge and BRST Generators for Space-Time Non-commutative U(1) Theory


  The Hamiltonian (gauge) symmetry generators of non-local (gauge) theories are
presented. The construction is based on the d+1 dimensional space-time
formulation of d dimensional non-local theories. The procedure is applied to
U(1) space-time non-commutative gauge theory. In the Hamiltonian formalism the
Hamiltonian and the gauge generator are constructed. The nilpotent BRST charge
is also obtained. The Seiberg-Witten map between non-commutative and
commutative theories is described by a canonical transformation in the
superphase space and in the field-antifield space. The solutions of classical
master equations for non-commutative and commutative theories are related by a
canonical transformation in the antibracket sense.

</DOC>
<DOC>
<DOCNO> 71297 </DOCNO>
The effect of primordial temperature fluctuations on the QCD transition


  We analyze a new mechanism for the cosmological QCD first-order phase
transition: inhomogeneous nucleation. The primordial temperature fluctuations
are larger than the tiny temperature interval, in which bubbles would form in
the standard picture of homogeneous nucleation. Thus the bubbles nucleate at
cold spots. We find the typical distance between bubble centers to be a few
meters. This exceeds the estimates from homogeneous nucleation by two orders of
magnitude. The resulting baryon inhomogeneities may affect primordial
nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 117575 </DOCNO>
Electron Firehose instability and acceleration of electrons in solar


  An electron distribution with a temperature anisotropy T_par/T_perp > 1 can
lead to the Electron Firehose instability (Here par and perp denote directions
relative to the background magnetic field B_0). Since possible particle
acceleration mechanisms in solar flares exhibit a preference of energizing
particles in parallel direction, such an anisotropy is expected during the
impulsive phase of a flare. The properties of the excited waves and the
thresholds for instability are investigated by using linearized kinetic theory.
These thresholds were connected to the pre-flare plasma parameters by assuming
an acceleration model acting exclusively in parallel direction. For usually
assumed pre-flare plasma conditions the electrons become unstable during the
acceleration process and lefthand circularly polarized waves with frequencies
of about the proton gyrofrequency are excited at parallel propagation.
Indications have been found, that the largest growth rates occur at oblique
propagation and the according frequencies lie well above the proton
gyrofrequency.

</DOC>
<DOC>
<DOCNO> 71425 </DOCNO>
Extra Dimensions: A View from the Top


  In models with compact extra dimensions, where the Standard Model fields are
confined to a 3+1 dimensional hyperplane, the $t \bar t$ production
cross-section at a hadron collider can receive significant contributions from
multiple exchange of KK modes of the graviton. These are carefully computed in
the well-known ADD and RS scenarios, taking the energy dependence of the sum
over graviton propagators into account. Using data from Run-I of the Tevatron,
95% C.L. bounds on the parameter space of both models are derived. For Run-II
of the Tevatron and LHC, discovery limits are estimated.

</DOC>
<DOC>
<DOCNO> 80648 </DOCNO>
Meron-cluster algorithms and chiral symmetry breaking in a (2+1)-d


  The recently developed Meron-Cluster algorithm completely solves the
exponentially difficult sign problem for a number of models previously
inaccessible to numerical simulation. We use this algorithm in a high-precision
study of a model of N=1 flavor of staggered fermions in (2+1)-dimensions with a
four-fermion interaction. This model cannot be explored using standard
algorithms. We find that the Z(2) chiral symmetry of this model is
spontaneously broken at low temperatures and that the finite-temperature chiral
phase transition is in the universality class of the 2-d Ising model, as
expected.

</DOC>
<DOC>
<DOCNO> 68140 </DOCNO>
Yukawa hierarchy from extra dimensions and infrared fixed points


  We discuss the existence of hierarchy of Yukawa couplings in the models with
extra spatial dimensions. The hierarchical structure is induced by the power
behavior of the cutoff dependence of the evolution equations which yield large
suppressions of couplings at the compactification scale. The values of coupling
constants at this scale can be made stable almost independently of the initial
input parameters by utilizing the infrared fixed point. We find that the Yukawa
couplings converge to the fixed points very quickly because of the enhanced
energy dependence of the suppression factor from extra dimensions as well as in
the case of large gauge couplings at high-energy scale.

</DOC>
<DOC>
<DOCNO> 71798 </DOCNO>
A Comparison of the Momentum Spectra in Deep Inelastic Scattering with


  The evolution of the logarithmic scaled energy spectra with energy scale, in
the framework of the modified leading logarithmic approximation (MLLA), is
investigated. The behaviour of the higher order moments of HERA deep inelastic
scattering data are compared with the analytic predictions of MLLA.

</DOC>
<DOC>
<DOCNO> 7956 </DOCNO>
Polymerized Membranes, a Review


  Membranes are of great technological and biological as well as theoretical
interest. Two main classes of membranes can be distinguished: Fluid membranes
and polymerized, tethered membranes. Here, we review progress in the
theoretical understanding of polymerized membranes, i.e. membranes with a fixed
internal connectivity. We start by collecting basic physical properties,
clarifying the role of bending rigidity and disorder, theoretically and
experimentally as well as numerically. We then give a thorough introduction
into the theory of self-avoiding membranes, or more generally non-local field
theories with delta-like interactions. Based on a proof of perturbative
renormalizability for non-local field-theories, renormalization group
calculations can be performed up to 2-loop order, which in 3 dimensions predict
a crumpled phase with fractal dimension of about 2.4. The tricritical behavior
of membranes is discussed and shown to be quite different from that of
polymers. Dynamical properties are studied in the same frame-work. Along the
same lines, disorder can be included leading to interesting applications. We
also construct a generalization of the O(N)-model, which in the limit N->0
reduces to self-avoiding membranes in analogy with the O(N)-model, which in the
limit N->0 reduces to self-avoiding polymers. We also describe the
instanton-contribution governing the large-order behavior of perturbation
theory. Some technical details are relegated to the appendices.

</DOC>
<DOC>
<DOCNO> 117500 </DOCNO>
A deep ROSAT survey XV. the average QSO spectrum and its evolution


  Using a sample of 165 X-ray selected QSOs from seven deep ROSAT fields we
investigate the X-ray spectral properties of an ``average''radio-quiet broad
line QSO as a function of redshift. The QSO stacked spectra, in the observers
0.1-2 keV band, in five redshift bins over the range 0.1<z<3.2 apparently
harden from an equivalent photon index of 2.6 at z=0.4 to ~2.1 at z=2.4 as seen
in other QSO samples. In contrast, the spectra in the 0.5-2 keV band show no
significant variation in spectral index with redshift. This suggests the
presence of a spectral upturn at low energies (<0.5 keV). Indeed, while at high
redshifts (z>1.0) the single power-law model gives an acceptable fit to the
data over the full energy band, at lower redshifts the spectra need a second
component at low energies, a `soft excess'. Inclusion of a simple model for the
soft excess, i.e. a black-body component (kT~100 eV), results in a significant
improvement to the model fit, and yields power-law slopes of 1.8-1.9, for all
redshift bins. This power-law is not inconsistent, within the error bars, with
those of nearby AGN in the 2-10 keV band, suggesting that the same intrinsic
power-law slope may continue from 10 keV down to below 0.5 keV. We caution that
there is a possibility that the spectral upturn observed may not represent a
real physical component but could be due to co-adding spectra with a large
dispersion in spectral indices. Regardless of the origin of the soft excess,
the average QSO spectrum has important consequences for the origin of the X-ray
background: the average spectra of the typical, faint, high redshift QSO are
significantly steeper than the spectrum of the X-ray background extending the
spectral paradox into the soft 0.1-2 keV X-ray band.

</DOC>
<DOC>
<DOCNO> 12981 </DOCNO>
The probability distribution of the conductance at the mobility edge


  The probability distribution of the conductance p(g) of disordered 2d and 3d
systems is calculated by transfer matrix techniques. As expected, p(g) is
Gaussian for extended states while for localized states it is log-normal. We
find that at the mobility edge p(g) is highly asymmetric and universal.

</DOC>
<DOC>
<DOCNO> 67865 </DOCNO>
B-meson hadroproduction cross sections and up-to-date models


  The comparison of B-meson production cross sections as the results of PYTHIA
code and Quark Gluon String Model (QGSM) is carried out for energies of proton
colliders: $Sp\bar(p)S$, Tevatron and LHC. Model predictions are based on the
theory of supercritical Pomeron exchanges with the phenomenological intercept
$\Delta_P$(0)=0.3, accepted for heavy quark production.Transverse momentum
spectra of B-mesons are also compared. It is shown that the cross sections
calculated with PYTHIA using CTEQ structure functions are in a contradiction
with the asymptotical estimation of B$\bar{B}$ production cross sections in
QGSM. Asymmetries between the spectra of $B^0$ and $\bar{B0}$ mesons are also
contradicting. The reasons of the difference are discussed.

</DOC>
<DOC>
<DOCNO> 84366 </DOCNO>
Solar System Tests of Higher-Dimensional Gravity


  The classical tests of general relativity - light deflection, time delay and
perihelion shift - are applied, along with the geodetic precession test, to the
five-dimensional extension of the theory known as Kaluza-Klein gravity, using
an analogue of the four-dimensional Schwarzschild metric. The perihelion
advance and geodetic precession calculations are generalized for the first time
to situations in which the components of momentum and spin along the extra
coordinate do not vanish. Existing data on light- bending around the Sun using
long- baseline radio interferometry, ranging to Mars using the Viking lander,
and the perihelion precession of Mercury all constrain a small parameter b
associated with the extra part of the metric to be less than |b| < 0.07 in the
solar system. An order-of-magnitude increase in sensitivity is possible from
perihelion precession, if better limits on solar oblateness become available.
Measurement of geodetic precession by the Gravity Probe B satellite will
improve this significantly, probing values of b with an accuracy of one part in
10^4 or more.

</DOC>
<DOC>
<DOCNO> 9926 </DOCNO>
Influence of temperature dependent inelastic scattering on the


  We have measured the differential resistance of mesoscopic gold wires of
different lengths connected to an aluminum superconductor as a function of
temperature and voltage. Our experimental results differ substantially from
theoretical predictions which assume an infinite temperature independent gap in
the superconductor. In addition to taking into account the temperature
dependence of the gap, we must also introduce a temperature dependent inelastic
scattering length in order to fit our data.

</DOC>
<DOC>
<DOCNO> 118907 </DOCNO>
PLANET observations of microlensing event OGLE-1999-BUL-23: limb


  We present PLANET observations of OGLE-1999-BUL-23, a binary-lens
microlensing event towards the Galactic bulge. PLANET observations in the I and
V bands cover the event from just before the first caustic crossing until the
end of the event. In particular, a densely-sampled second caustic crossing
enables us to derive the linear limb-darkening coefficients of the source star;
c_V = 0.786^{+0.080}_{-0.078} and c_I = 0.632^{+0.047}_{-0.037}. Combined
analysis of the light curve and the color-magnitude diagram suggests that the
source star is a G/K subgiant in the Galactic bulge (T_eff = 4800 K). The
resulting linear limb-darkening coefficient of the source is consistent with
theoretical predictions, although it is likely that non-linearity of the
stellar surface brightness profile complicates the interpretation, especially
for the I band. The global light curve fit to the data indicates that the event
is due to a binary lens of a mass ratio q = 0.39 and a projected separation d =
2.42. The lens/source relative proper motion is (22.8 +_ 1.5) km/s/kpc, typical
of bulge/bulge or bulge/disk events.

</DOC>
<DOC>
<DOCNO> 120243 </DOCNO>
CO and Near-Infrared Observations of High-Redshift Submillimeter


  I discuss our ongoing Owens Valley Millimeter Array observations and Keck
near-infrared wavelength observations of the high-redshift sub-mm population of
galaxies. These observations are important for our understanding of the distant
universe since the sub-mm population accounts for a large fraction of the
extragalactic background at mm/sub-mm wavelengths and contributes significantly
to the total amount of star-formation and AGN activity at high redshift. The CO
data suggest that the sub-mm galaxies are analogous to the gas-rich
ultraluminous systems found in the local universe. Initial near-infrared data
show that many of the sub-mm galaxies are faint-red sources which are
undetected at ultraviolet/optical wavelengths. These results highlight the
importance that future sensitive mm-wavelength instruments, such as the LMT and
ALMA, will have on our understanding of the early evolution and formation of
galaxies.

</DOC>
<DOC>
<DOCNO> 68607 </DOCNO>
A Sterile Neutrino Needed for Heavy-Element Nucleosynthesis


  A neutrino mass-mixing scheme which successfully avoids the "alpha effect,"
allowing r-process nucleosynthesis in the neutrino-heated ejecta of supernovae,
quite independently requires the same parameters as the scheme which best fits
all current indications for neutrino mass. The significance for particle
physics is this independent evidence for (1) at least one light sterile
neutrino, nu_s; (2) a near maximally-mixed nu_mu-nu_tau doublet split from a
lower mass nu_mu-nu_s doublet; (3) nu_mu-nu_e mixing >~ 10^-4; and (4) a
splitting between the doublets (measured by the nu_mu-nu_e mass difference) >~
1 eV^2, favoring the upper part of the LSND range. If correct, it is
tantalizing that neutrinos with tiny masses which mix with sterile species have
profound effects on massive objects and the creation of the heaviest elements.

</DOC>
<DOC>
<DOCNO> 120224 </DOCNO>
Chemical Abundances in our Galaxy and Other Galaxies Derived from H II


  We discuss the accuracy of the abundance determinations of H II regions in
our Galaxy and other galaxies. We focus on the main observational constraints
derived from abundance determinations that have implications for models of
galactic chemical evolution: a) the helium to hydrogen abundance ratio, He/H;
b) the oxygen to hydrogen abundance ratio, O/H; c) the carbon to oxygen
abundance ratio, C/O; d) the helium to oxygen and helium to heavy elements
abundance ratios, Delta Y/ Delta O and Delta Y/ Delta Z; and e) the primordial
helium abundance, Yp.

</DOC>
<DOC>
<DOCNO> 101346 </DOCNO>
A Discourse on the Benney Equation


  It is shown that the Benney system is equivalent to a one body classical
dynamical problem in which the interaction potential is a functional of the
action function. The general solution of this equation is responsible for the
general solution of the Benney system. Some particular solutions of the
selfconsistent Hamilton-Jacobi equation arising in this investigation are
presented in explicit form.

</DOC>
<DOC>
<DOCNO> 85234 </DOCNO>
Auto-parallel equation as Euler-Lagrange's equation in spaces with


  The auto-parallel equation over spaces with affine connections and metrics is
considered as a result of the application of the method of Lagrangians with
covariant derivatives (MLCD) on a given Lagrangian density.

</DOC>
<DOC>
<DOCNO> 120167 </DOCNO>
Intrinsic colour calibration for F, G, K stars


  We derive an intrinsic colour calibration for F--K stars using broad band
Johnson colours and line indices KP and HP2. Through this calibration we can
determine E(B-V) of an individual star within 0.03 mag. The E(B-V) values thus
derived are in excellent agreement with those derived from Stromgren photometry
through the Schuster & Nissen (1989) calibration. The agreement is also good
with the reddening maps of Burstein & Heiles (1982) and Schlegel et al (1998),
although in this case there exists a small offset of about 0.01 mag. This
calibration may be applied to the large body of data of the HK survey extension
which will be published in the near future.

</DOC>
<DOC>
<DOCNO> 151236 </DOCNO>
Exact Wavefunctions in a Noncommutative Field Theory


  We consider the nonrelativistic field theory with a quartic interaction on a
noncommutative plane. We compute the four point scattering amplitude within
perturbative analysis to all orders and identify the beta function and the
running of the coupling constant. Since the theory admits an equivalent
description via the N particle Schrodinger equation, we regain the scattering
amplitude by finding an exact scattering wavefunction of the two body equation.
The wave function for the bound state is also identified. These wave functions
unusually have two center positions in the relative coordinates. The separation
of the centers is in the transverse direction of the total momentum and grows
linearly with the noncommutativity scale and the total momentum, exhibiting the
stringy nature of the noncommutative field theory.

</DOC>
<DOC>
<DOCNO> 10307 </DOCNO>
Stripes in charge-transfer Mott insulators: effects of lattice


  Applying the canonical transformation with the 1/\lambda perturbation
expansion in the nonadiabatic and intermediate regime and the discrete
generalisation of Pekar's continuous nonlinear equation in the extreme
adiabatic regime we show that there are no strings in narrow-band ionic
insulators due to the Frohlich electron-phonon interaction alone. The
multi-polaron system is a homogeneous state in a wide range of physically
interesting parameters, no matter how strong correlations are. At the same time
the Frohlich interaction allows the antiferromagnetic interactions and/or a
short-range electron-phonon interactions to form short strings in doped
antiferromagnetic insulators if the static dielectric constant is large enough.

</DOC>
<DOC>
<DOCNO> 10007 </DOCNO>
Nonequilibrium Josephson current in ballistic multiterminal


  We study the nonequilibrium Josephson current in a long two-dimensional
ballistic SNS-junction with a normal reservoir coupled to the normal part of
the junction. The current for a given superconducting phase difference $\phi$
oscillates as a function of voltage applied between the normal reservoir and
the SNS-junction. The period of the oscillations is $\pi \hbar v_F/L$, with $L$
the length of the junction, and the amplitude of the oscillations decays as
$V^{-3/2}$ for $eV \gg \hbar v_{F}/L$ and zero temperature. The critical
current $I_c$ shows a similar oscillating, decaying behavior as a function of
voltage, changing sign every oscillation. Normal specular or diffusive
scattering at the NS-interfaces does not qualitatively change the picture.

</DOC>
<DOC>
<DOCNO> 83260 </DOCNO>
A Real-Time Novelty Detector for a Mobile Robot


  Recognising new or unusual features of an environment is an ability which is
potentially very useful to a robot. This paper demonstrates an algorithm which
achieves this task by learning an internal representation of `normality' from
sonar scans taken as a robot explores the environment. This model of the
environment is used to evaluate the novelty of each sonar scan presented to it
with relation to the model. Stimuli which have not been seen before, and
therefore have more novelty, are highlighted by the filter. The filter has the
ability to forget about features which have been learned, so that stimuli which
are seen only rarely recover their response over time. A number of robot
experiments are presented which demonstrate the operation of the filter.

</DOC>
<DOC>
<DOCNO> 69487 </DOCNO>
Nature of Chiral Transition in QCD and Sigma Meson


  After showing the characteristic features of the chiral transition in QCD at
finite temperature $T$, we note the significance of the sigma-mesonic mode in
the chiral transition : Sigma meson may be regarded as the "Higgs particle" in
QCD, though the existence of such a mode in the real world is still unclear. We
show the properties of the sigma meson in hot and/or hadronic matter, from
which we propose experiments to reveal the existence the sigma meson clearly;
the experiments include relativistic heavy-ion collisions to create hot
hadronic matter, and electro-production in heavy nuclei.

</DOC>
<DOC>
<DOCNO> 116512 </DOCNO>
Nonlinear, ground-state, pump-probe spectroscopy


  A theory of pump-probe spectroscopy is developed in which optical fields
drive two-quantum, Raman-like transitions between ground state sublevels. Three
fields are incident on an ensemble of atoms. Two of the fields act as the pump
field for the two-quantum transitions. The absorption or gain of an additional
probe field is monitored as a function of its detuning from one of the fields
which constitutes the pump field. Although the probe absorption spectrum
displays features common to those found in pump-probe spectroscopy of
single-quantum transitions, new interference effects are found to modify the
spectrum. Many of these features can be explained within the context of a
dressed atom picture.

</DOC>
<DOC>
<DOCNO> 67919 </DOCNO>
CP violating Z t anti-t and gamma t anti-t Couplings at a Future e+ e-


  The effect of new operators that give rise to CP-violating couplings of the
type $Z t \bar{t}$ and $\gamma t \bar{t}$ are examined at future electron
positron Linear Colliders (FLC). The impact of these CP-violating interactions
over Standard Model predictions was studied for the process e+ e^- -> t anti-t
with the subsequent decays t -> b l+ nu_l and anti-t -> anti-b l- anti-nu_l,
called as dilepton mode, and t -> b l^+ nu_l and anti-t -> anti-b anti-q q' or
t -> b q anti-q' and anti-t -> anti-b l- anti-nu_l, called as single lepton
mode, where the final leptons are l = e or mu, and the final quarks are q(q')=
u(d) or c(s). Polarized electron beam and CP observables and asymmetries are
used to impose bounds on the anomalous couplings.

</DOC>
<DOC>
<DOCNO> 10088 </DOCNO>
d-wave nonadiabatic superconductivity


  The inclusion of nonadiabatic corrections to the electron-phonon interaction
leads to a strong momentum dependence in the generalized Eliashberg equations
beyond Migdal's limit. For a s-wave symmetry of the order parameter, this
induced momentum dependence leads to an enhancement of Tc when small momentum
transfer is dominant. Here we study how the d-wave symmetry affects the above
behavior. We find that the nonadiabatic corrections depend only weakly on the
symmetry of the order parameter provided that only small momentum scatterings
are allowed for the electron-phonon interaction. In this situation, We show
that also for a d-wave symmetry of the order parameter, the nonadiabatic
corrections enhance Tc. We also discuss the possible interplay and crossover
between s- and d-wave depending on the material's parameters.

</DOC>
<DOC>
<DOCNO> 122196 </DOCNO>
Some Common Problems and Challenges that Emission-Line Stars Present


  Four examples are given of problems that arise in the study of emission-line
stars, each of which deserves further quantitative study. (1) Archival slit
spectra of \eta Car show that epochs of low excitation have occurred regularly
in the 2020 day period of Damineli et al. since at least 1948. They last about
10 percent of the period. Earlier slit spectra (1899 -1919) suggest that the
the object was always in a low excitation state at that time. This result may
be connected with the gradual brightening of eta Car through most of the 20th
century. (2) FeII and [FeII] emission in Mira variables is probably
chromospheric. It would be important to understand how this is excited and its
relation to mass loss and dust formation in Miras. (3) Declines of RCB stars
are due to eclipses by dust clouds. At such times a rich emission line spectrum
from the outer atmosphere of the star is seen. The quantitative study of the
changes in this spectrum as more and more of the star is eclipsed should yield
important information on the extended atmosphere of these objects. (4) In deep
minima when the entire star is eclipsed, RCB stars show a broad-line emission
spectrum. The excitation of this spectrum, particularly HeI 3888A, constitutes
a puzzle. Two possible excitation mechanisms are discussed.

</DOC>
<DOC>
<DOCNO> 84806 </DOCNO>
On the influence of gravitational radiation on a gyroscope


  We calculate the precession of a gyroscope at rest in a Bondi spacetime. It
is shown that, far from the source, the leading term in the rate of precession
of the gyroscope is simply expressed through the news function of the system,
and vanishes if and only if there is no news. Rough estimates are presented,
illustrating the order of magnitude of the expected effect for different
scenarios. It is also shown from the next order term that non-radiative (but
time dependent) spacetimes will produce a gyroscope precession of that order,
providing thereby ``observational'' evidence for the violation of the Huygens's
principle.

</DOC>
<DOC>
<DOCNO> 70978 </DOCNO>
Bilinear R-parity violating SUSY: Solving the solar and atmospheric


  Bilinear R-parity violation is a simple extension of the MSSM allowing for
Majorana neutrino masses. One of the three neutrinos picks up mass by mixing
with the neutralinos of the MSSM, while the other two neutrinos gain mass from
1-loop corrections. Once 1-loop corrections are carefully taken into account
the model is able to explain solar and atmospheric neutrino data for specific
though simple choices of the R-parity violating parameters.

</DOC>
<DOC>
<DOCNO> 72137 </DOCNO>
Probing the QCD vacuum


  Heavy quark bound states are used as significative probes of the QCD vacuum
and the mechanism of confinement.

</DOC>
<DOC>
<DOCNO> 100871 </DOCNO>
Asymptotics of numbers of branched coverings of a torus and volumes of


  We compute the asymptotics of the number of connected branched coverings of a
torus as their degree goes to infinity and the ramification type stays fixed.
These numbers are equal to the volumes of the moduli spaces of pairs (curve,
holomorphic differential) with fixed multiplicities of zeros of the
differential and have several applications in ergodic theory.

</DOC>
<DOC>
<DOCNO> 119884 </DOCNO>
Weakly Self-Interacting Dark Matter and the Structure of Dark Halos


  We study the formation of dark halos in a $\Lambda$CDM universe under the
assumption that Cold Dark Matter particles have a finite cross-section for
elastic collisions. We compare evolution when CDM mean free paths are
comparable to halo sizes with the collisionless and fluid limits. We show that
a few collisions per particle per Hubble time at halo centre can substantially
affect the central density profile. Cross-sections an order of magnitude larger
produce sufficient relaxation for rich clusters to develop core radii in the
range 100-200 $h^{-1}$kpc. The structural evolution of halos is a competition
between collisional relaxation caused by individual particle interactions and
violent relaxation resulting from the infall and merging processes by which
clusters grow. Although our simulations concentrate on systems of cluster size,
we can scale our results to address the halo structure expected for dwarf
galaxies. We find that collision cross-sections sufficiently large to
significantly modify the cores of such galaxies produce cluster cores which are
too large and/or too round to be consistent with observation. Thus the simplest
model for self-interacting dark matter is unable to improve fits to published
dwarf galaxy rotation curves without violating other observational constraints.

</DOC>
<DOC>
<DOCNO> 102508 </DOCNO>
Short proof of the Gallai-Edmonds Structure Theorem


  We derive the Gallai-Edmonds Structure Theorem from Hall's Theorem.

</DOC>
<DOC>
<DOCNO> 10540 </DOCNO>
Current distribution in Hall bars and breakdown of the quantum Hall


  A numerical study is made of current distribution in small Hall bars with
disorder. It is observed, in particular, that in the Hall-plateau regime the
Hall current tends to concentrate near the sample edges while it diminishes on
average in the sample interior as a consequence of localization. Also reported
is another numerical experiment on a related, but rather independent topic, the
breakdown of the quantum Hall effect. It is pointed out that the competition of
the Hall field with disorder in the sample interior, an intra-subband process,
can account for both the magnitude and magnetic-field dependence (proportional
to B^{3/2}) of the critical breakdown fields observed experimentally.

</DOC>
<DOC>
<DOCNO> 12857 </DOCNO>
Susceptibility, Magnetization Process and ESR Studies on the Helical


  The static and dynamic magnetic properties of an $S=1/2$ stacked triangular
antiferromagnet RbCuCl$_{3}$ with a helical spin structure due to lattice
distortion were investigated by susceptibility, high-field magnetization
process and ESR measurements. The susceptibilities were analyzed by
high-temperature expansion approximation in terms of ferromagnetic intrachain
coupling and the antiferromagnetic interchain coupling. The magnetization
saturates at $H_{\rm s}\approx 66.8$ T at 1.5 K, the value of which is twice
that of CsCuCl$_3$. A small magnetization jump indicative of a phase transition
was observed at $H_{\rm c}=21.2$ T $\approx (1/3)H_{\rm s}$ for $H{\perp}c$.
ESR modes observed for $H\parallel c$ are well described by the calculation
based on the helical spin structure. From the present measurements, the
ferromagnetic intrachain and two kinds of antiferromagnetic interchain exchange
interactions, and the planar anisotropy energy were determined as $J_0/k_{\rm
B}=25.7$ K, $J_1/k_{\rm B}=-10.6$ K, $J_1'/k_{\rm B}=-17.4$ K, and
${\Delta}J_0/k_{\rm B}=-0.45$ K, respectively.

</DOC>
<DOC>
<DOCNO> 72167 </DOCNO>
A Phenomenological Model of the Baryons The Body Center Cubic Model of


  From the quark confinement idea, we conjecture that the quarks compose
colorless particles (uud and udd - the Lee Particles) and then the Lee
Particles construct a body center cubic lattice in the vacuum. In terms of the
energy band theory, from the symmetries of the body center cubic periodic
field, we deduce the baryon spectrum (with a united mass formula) using only 2
flavored quarks u and d. We also predict some new baryons: $\Lambda^{0}$(2559),
$\Lambda_{C}^{+}$(6659), $\Lambda_{b}^{0}$(10159).... The experiments to find
the long lifetime baryon $\Lambda^{0}$(2559) should be done first.

</DOC>
<DOC>
<DOCNO> 85274 </DOCNO>
The kernel of the edth operators on higher-genus spacelike two-surfaces


  The dimension of the kernels of the edth and edth-prime operators on closed,
orientable spacelike 2-surfaces with arbitrary genus is calculated, and some of
its mathematical and physical consequences are discussed.

</DOC>
<DOC>
<DOCNO> 152500 </DOCNO>
7-Branes and Higher Kaluza-Klein Branes


  We present and study a new chain of 10-d T duality related solutions and
their 11-d parents whose existence had been predicted in the literature based
in U duality requirements in 4 d. The first link is the S dual of the D7-brane.
The next link has 6 spatial worldvolume dimensions, it is charged w.r.t. the RR
7-form but depends only on 2 transverse dimensions since the third has to be
compactified in a circle and is isometric and hence is similar in this respect
to the KK monopole. The next link has 5 spatial worldvolume dimensions, it is
charged w.r.t. the RR 6-form but depends only on 2 transverse dimensions since
the 3rd and 4th have to be compactified in circles and are isometric and so on.
All these solutions are identical when reduced over the p spatial worldvolume
dimensions and preserve a 1/2 on the supersymmetries. Their masses depend on
the square of the radii of the isometric directions, just as for the KK
monopole. We give a general map of these branes and their duality relations and
show how they must appear in the supersymmetry algebra.

</DOC>
<DOC>
<DOCNO> 13645 </DOCNO>
Role of a parallel magnetic field in two dimensional disordered clusters


  An ensemble of 2d disordered clusters with a few electrons is studied as a
function of the Coulomb energy to kinetic energy ratio r_s. Between the Fermi
system (small r_s) and the Wigner molecule (large r_s), an interaction induced
delocalization of the ground state takes place which is suppressed when the
spins are aligned by a parallel magnetic field. Our results confirm the
existence of an intermediate regime where the Wigner antiferromagnetism
defavors the Stoner ferromagnetism and where the enhancement of the Lande g
factor observed in dilute electron systems is reproduced.

</DOC>
<DOC>
<DOCNO> 69627 </DOCNO>
Nonsingular deformations of singular compactifications, the cosmological


  We consider deformations of the singular "global cosmic string"
compactifications, known to naturally generate exponentially large scales. The
deformations are obtained by allowing a constant curvature metric on the brane
and correspond to a choice of integration constant. We show that there exists a
unique value of the integration constant that gives rise to a nonsingular
solution. The metric on the brane is dS_4 with an exponentially small value of
expansion parameter. We derive an upper bound on the brane cosmological
constant. We find and investigate more general singular solutions---``dilatonic
global string" compactifications---and show that they can have nonsingular
deformations. We give an embedding of these solutions in type IIB supergravity.
There is only one class of supersymmetry-preserving singular dilatonic
solutions. We show that they do not have nonsingular deformations of the type
considered here.

</DOC>
<DOC>
<DOCNO> 83146 </DOCNO>
A Consistency-Based Model for Belief Change: Preliminary Report


  We present a general, consistency-based framework for belief change.
Informally, in revising K by A, we begin with A and incorporate as much of K as
consistently possible. Formally, a knowledge base K and sentence A are
expressed, via renaming propositions in K, in separate languages. Using a
maximization process, we assume the languages are the same insofar as
consistently possible. Lastly, we express the resultant knowledge base in a
single language. There may be more than one way in which A can be so extended
by K: in choice revision, one such ``extension'' represents the revised state;
alternately revision consists of the intersection of all such extensions.
  The most general formulation of our approach is flexible enough to express
other approaches to revision and update, the merging of knowledge bases, and
the incorporation of static and dynamic integrity constraints. Our framework
differs from work based on ordinal conditional functions, notably with respect
to iterated revision. We argue that the approach is well-suited for
implementation: the choice revision operator gives better complexity results
than general revision; the approach can be expressed in terms of a finite
knowledge base; and the scope of a revision can be restricted to just those
propositions mentioned in the sentence for revision A.

</DOC>
<DOC>
<DOCNO> 102356 </DOCNO>
Mellin transform of Whittaker functions


  In this note we show that for an arbitrary semisimple Lie group and any
admissible irreducible Banach representation the Mellin transforms of Whittaker
functions extend to meromorphic functions. We locate the possible poles.

</DOC>
<DOC>
<DOCNO> 100522 </DOCNO>
Noncommutative gauge theory for Poisson manifolds


  A noncommutative gauge theory is associated to every Abelian gauge theory on
a Poisson manifold. The semi-classical and full quantum version of the map from
the ordinary gauge theory to the noncommutative gauge theory (Seiberg-Witten
map) is given explicitly to all orders for any Poisson manifold in the Abelian
case. In the quantum case the construction is based on Kontsevich's formality
theorem.

</DOC>
<DOC>
<DOCNO> 151203 </DOCNO>
Bosonic Open Strings in a Tachyonic Background Field


  We study a bosonic open string coupled to a tachyonic background field $T[X]$
and find that the tachyon field can effectively be replaced by a configuration
of D-branes placed at either the zeros or the critical points of $T[X]$,
depending on our choice of boundary conditions. This dual picture of the open
string tachyon is explored in detail for the explicit case when the tachyonic
field is quadratic.

</DOC>
<DOC>
<DOCNO> 10081 </DOCNO>
Generalization of the Kolmogorov-Sinai entropy: Logistic- and


  We numerically calculate, at the edge of chaos, the time evolution of the
nonextensive entropic form $S_q \equiv [1-\sum_{i=1}^W p_i^q]/[q-1]$ (with
$S_1=-\sum_{i=1}^Wp_i \ln p_i$) for two families of one-dimensional dissipative
maps, namely a logistic- and a periodic-like with arbitrary inflexion $z$ at
their maximum. At $t=0$ we choose $N$ initial conditions inside one of the $W$
small windows in which the accessible phase space is partitioned; to neutralize
large fluctuations we conveniently average over a large amount of initial
windows. We verify that one and only one value $q^*<1$ exists such that the
$\lim_{t\to\infty} \lim_{W\to\infty} \lim_{N\to\infty} S_q(t)/t$ is {\it
finite}, {\it thus generalizing the (ensemble version of) Kolmogorov-Sinai
entropy} (which corresponds to $q^*=1$ in the present formalism). This special,
$z$-dependent, value $q^*$ numerically coincides, {\it for both families of
maps and all $z$}, with the one previously found through two other independent
procedures (sensitivity to the initial conditions and multifractal $f(\alpha)$
function).

</DOC>
<DOC>
<DOCNO> 117540 </DOCNO>
Deconvolving the Beam in Small Angular Scale CMB Experiments


  This paper is concerned with experiments which measure CMB anisotropies on
small angular scales. A certain coverage, a beam structure and a level of
uncorrelated noise define each experiment. We focus our atention on the
reversion of the beam average. In each experiment, we look for the best
pixelization for reversion, namely, for the pixelization that -after reversion-
leads to good maps containing right spectra for the most wide range of angular
scales. Squared pixels having different sizes "smaller" than the beam radius
are considered. For a given size, the following question arises: How well can
we assign a temperature to each pixel? Various mathematical methods are used to
show that, in practice, this assignation -beam reversion or deconvolution- only
leads to right spectra for pixel sizes greater than a certain lower limit close
to the half of the beam radius. This limit is estimated for negligible and
relevant levels of noise and also for spherically symmetric and asymmetric
beams. After this general study, we focus our attention on two feasible
detectors (which have been proposed to be on board of PLANCK satellite). For
each of them, we estimate the size of the most appropriate pixelization
compatible with beam reversion, difraction, observational strategy et cetera
and, then, we answer the following question: Which is the part of the angular
power spectrum which can be extracted from appropriately pixelized maps after
deconvolution?

</DOC>
<DOC>
<DOCNO> 8766 </DOCNO>
Does localization occur in a hierarchical random-matrix model for


  We use random-matrix theory and supersymmetry techniques to work out the
two-point correlation function between states in a hierarchical model which
employs Feshbach's chaining hypothesis: Classes of many-body states are
introduced. Only states within the same or neighboring classes are coupled. We
assume that the density of states per class grows monotonically with class
index. The problem is mapped onto a one-dimensional non-linear sigma model. In
the limit of a large number of states in each class we derive the critical
exponent for the growth of the level density with class index for which
delocalization sets in. From a realistic modelling of the class-dependence of
the level density, we conclude that the model does not predict Fock-space
localization in nuclei.

</DOC>
<DOC>
<DOCNO> 116492 </DOCNO>
Sommerfeld Particle in Static Magnetic Field: Tunneling and Delayed


  Motion of a charged particle with finite size, described by Sommerfeld model,
in static magnetic field has two peculiar features: 1.) there is the effect of
tunneling - Sommerfeld particle overcomes the barrier and finds itself in the
forbidden, from classical point of view, area; 2.) the untwisting of trajectory
in cyclotron for Sommerfeld particle is strongly delayed compared to that of a
classical particle.

</DOC>
<DOC>
<DOCNO> 174475 </DOCNO>
Interacting pion pairs in nuclear matter


  The pion-production $\pi^+ A \to \pi^+\pi^{\pm} A'$ reactions were studied on
nuclei $^{2}H$, $^{12}C$, $^{40}Ca$ and $^{208}Pb$ at a pion energy of
$T_{\pi^{+}}$=283 MeV using the CHAOS spectrometer. The experimental results
are reduced to differential cross sections and compared to both theoretical
predictions and reaction phase space. Near the $2m_{\pi}$ threshold pion pairs
couple to $(\pi\pi)_{I=J=0}$ when produced in the $\pi^+\to \pi^+\pi^-$
reaction channel. The $\cal C$$_{\pi\pi}^A$ ratio between the
$\pi^{+}\pi^{\pm}$ invariant masses on nuclei and on the nucleon is also
presented. The marked near-threshold enhancement of $\cal C$$_{\pi^+\pi^-}^A$
is consistent with theoretical predictions addressing the partial restoration
of chiral symmetry. On the opposite, nuclear matter weakly influences $\cal
C$$_{\pi^+\pi^+}^A$.

</DOC>
<DOC>
<DOCNO> 14107 </DOCNO>
Dynamics and Patterning of Screw Dislocations in Two Dimensions


  To understand how dislocations form ordered structures during the deformation
of metals, we perform computer simulation studies of the dynamics and
patterning of screw dislocations in two dimensions. The simulation is carried
out using an idealized atomistic model with anti-plane displacements only; we
show that this system is an analog of the two-dimensional XY rotor model.
Simulation studies show that under a constant applied shear strain rate, the
flow of dislocations spontaneously coalesces to form narrow dislocation-rich
channels separated by wide dislocation-free regions, so that the applied strain
is localized into slip bands. We argue that this pattern formation represents a
phase separation into ordered and disordered phases associated with the XY
model, and conjecture that thermodynamic forces drive strain localization.

</DOC>
<DOC>
<DOCNO> 151512 </DOCNO>
Isometries in anti-de Sitter and Conformal Superspaces


  We derive explicit forms for the superisometries of a wide class of
supercoset manifolds, including those with fermionic generators in the
stability group. We apply the results to construct the action of SU(2,2|4) on
three supercoset manifolds: (10|32)-dimensional AdS_5 x S^5 superspace,
(4|16)-dimensional conformal superspace, and a novel (10|16)-dimensional
conformal superspace. Using superembedding techniques, we show, to lowest
non-trivial order in the fermions, that at the boundary of AdS_5, the
superisometries of the AdS_5 x S^5$ superspace reduce to the standard N=4
superconformal transformations. In particular, half of the 32 fermionic
coordinates decouple from the superisometries.

</DOC>
<DOC>
<DOCNO> 100644 </DOCNO>
The unitary implementation of a locally compact quantum group action


  In this paper we study actions of locally compact quantum groups on von
Neumann algebras and prove that every action has a canonical unitary
implementation, paralleling Haagerup's classical result on the unitary
implementation of a locally compact group action. This result is an important
tool in the study of quantum groups in action. We will use it in this paper to
study subfactors and inclusions of von Neumann algebras. When alpha is an
action of a locally compact quantum group on the von Neumann algebra N we can
give necessary and sufficient conditions under which the inclusion of the fixed
point algebra in the algebra N in the crossed product, is a basic construction.
When alpha is an outer and integrable action on a factor N we prove that the
inclusion of the fixed point algebra in the algebra N is irreducible, of depth
2 and regular, giving a converse to the results of Enock and Nest. Finally we
prove the equivalence of minimal and outer actions and we generalize a theorem
of Yamanouchi: every integrable outer action with infinite fixed point algebra
is a dual action.

</DOC>
<DOC>
<DOCNO> 69210 </DOCNO>
Neutralino Proton Cross Sections For Dark Matter In SUGRA And D-BRANE


  Neutralino proton cross sections are examined for models with R-parity
invariance with universal soft breaking (mSUGRA) models, nonuniversal SUGRA
models, and D-brane models. The region of parameter space where current dark
matter detectors are sensitive, i.e. $1\times 10^{-6}$ pb, is examined. For
mSUGRA models, detectors are sampling parts of the parametr space for
tan$\beta >\sim 25$. The nonuniversal models can achieve cross
sections that are a factor of 10-100 bigger or smaller then the universal one
and in the former case sample regions tan$\beta >\sim 4$. The
D-brane models considered require tan$\beta >\sim 15$. The inclusion
of CP violating phases reduces the cross section by a factor of $\sim$ 2-3 (but
also requires considerable fine tuning at the GUT scale). The expected particle
spectra at accelerators are examined and seen to differ for each model. Three
new regions of possible coannihilation are noted.

</DOC>
<DOC>
<DOCNO> 117449 </DOCNO>
Star Formation: Lessons from Taurus


  The Taurus molecular cloud complex is the paradigm for quiescent,
low-density, isolated star formation. Yet the age distribution of its stellar
population indicates that star formation is a rapid and dynamic process,
inconsistent with the old picture of magnetically-controlled protostellar cloud
collapse. Instead, Taurus seems to have formed stars in a manner qualitatively
consistent with the rapid cloud formation and dispersal inferred for other,
higher-density star-forming regions. I suggest that the Taurus clouds were
formed rapidly by the collision of atomic gas streams in the interstellar
medium, and that star formation ensued immediately afterward.

</DOC>
<DOC>
<DOCNO> 117119 </DOCNO>
Complex Langevin Equation and the Many-Fermion Problem


  We study the utility of a complex Langevin (CL) equation as an alternative
for the Monte Carlo (MC) procedure in the evaluation of expectation values
occurring in fermionic many-body problems. We find that a CL approach is
natural in cases where non-positive definite probability measures occur, and
remains accurate even when the corresponding MC calculation develops a severe
``sign problem''. While the convergence of CL averages cannot be guaranteed in
principle, we show how convergent results can be obtained in three examples
ranging from simple one-dimensional integrals over quantum mechanical models to
a schematic shell model path integral.

</DOC>
<DOC>
<DOCNO> 100396 </DOCNO>
Polar Varieties and Efficient Real Elimination


  Let $S_0$ be a smooth and compact real variety given by a reduced regular
sequence of polynomials $f_1, ..., f_p$. This paper is devoted to the
algorithmic problem of finding {\em efficiently} a representative point for
each connected component of $S_0$ . For this purpose we exhibit explicit
polynomial equations that describe the generic polar varieties of $S_0$. This
leads to a procedure which solves our algorithmic problem in time that is
polynomial in the (extrinsic) description length of the input equations $f_1,
>..., f_p$ and in a suitably introduced, intrinsic geometric parameter, called
the {\em degree} of the real interpretation of the given equation system $f_1,
>..., f_p$.

</DOC>
<DOC>
<DOCNO> 101386 </DOCNO>
Spencer manifolds


  Almost-complex and hyper-complex manifolds are considered in this paper from
the point of view of complex analysis and potential theory. The idea of
holomorphic coordinates on an almost-complex manifold $(M,\mathbf{J}%)$ is
suggested by D. Spencer. For hypercomplex manifolds we introduce the notion of
hyper-holomorphic function and develop some analogous statements. Elliptic
equations are developed in a different way than D. Spencer. In general here we
describe only the formal aspect of the developed theory.

</DOC>
<DOC>
<DOCNO> 116347 </DOCNO>
The decay of multiscale signals - deterministic model of the Burgers


  This work is devoted to the study of the decay of multiscale deterministic
solutions of the unforced Burgers' equation in the limit of vanishing
viscosity.
  A deterministic model of turbulence-like evolution is considered. We con-
struct the initial perturbation as a piecewise linear analog of the Weierstrass
function. The wavenumbers of this function form a "Weierstrass spectrum", which
accumulates at the origin in geometric progression."Reverse" sawtooth functions
with negative initial slope are used in this series as basic functions, while
their amplitudes are chosen by the condition that the distribution of energy
over exponential intervals of wavenumbers is the same as for the continuous
spectrum in Burgers turbulence. Combining these two ideas allows us to obtain
an exact analytical solution for the velocity field. We also notice that such
multiscale waves may be constructed for multidimensional Burgers' equation.
  This solution has scaling exponent h=-(1+n)/2 and its evolution in time is
self-similar with logarithmic periodicity and with the same average law L(t) as
for Burgers turbulence. Shocklines form self-similar regular tree-like struc-
tures. This model also describes important properties of the Burgers turbulence
such as the self-preservation of the evolution of large scale structures in the
presence of small scales perturbations.

</DOC>
<DOC>
<DOCNO> 169580 </DOCNO>
Quantization of Soliton Cellular Automata


  A method of quantization of classical soliton cellular automata (QSCA) is put
forward that provides a description of their time evolution operator by means
of quantum circuits that involve quantum gates from which the associated
Hamiltonian describing a quantum chain model is constructed.
 The intrinsic parallelism of QSCA, a phenomenon first known from quantum
computers, is also emphasized.

</DOC>
<DOC>
<DOCNO> 150651 </DOCNO>
Dual Instantons


  We show how to map the Belavin-Polyakov instantons of the O(3)-nonlinear
$\sigma-$model to a dual theory where they then appear as nontopological
solitons. They are stationary points of the Euclidean action in the dual
theory, and moreover, the dual action and the O(3)-nonlinear $\sigma-$model
action agree on shell.

</DOC>
<DOC>
<DOCNO> 169753 </DOCNO>
Quantum Computing with Neutral Atoms in an Optical Lattice


  We present a proposal for quantum information processing with neutral atoms
trapped in optical lattices as qubits. Initialization and coherent control of
single qubits can be achieved with standard laser cooling and spectroscopic
techniques. We consider entangling two-qubit logic gates based on optically
induced dipole-dipole interactions, calculating a figure-of-merit for various
protocols. Massive parallelism intrinsic to the lattice geometry makes this an
intriguing system for scalable, fault-tolerant quantum computation.

</DOC>
<DOC>
<DOCNO> 83275 </DOCNO>
Compiling Language Models from a Linguistically Motivated Unification


  Systems now exist which are able to compile unification grammars into
language models that can be included in a speech recognizer, but it is so far
unclear whether non-trivial linguistically principled grammars can be used for
this purpose. We describe a series of experiments which investigate the
question empirically, by incrementally constructing a grammar and discovering
what problems emerge when successively larger versions are compiled into finite
state graph representations and used as language models for a medium-vocabulary
recognition task.

</DOC>
<DOC>
<DOCNO> 122655 </DOCNO>
Combined MEM and MHW analysis of CMB observations


  We present a combined maximum-entropy method (MEM) and Mexican Hat wavelet
(MHW) analysis in order to recover the different components of the microwave
sky. We apply this technique to simulated observations by the ESA Planck
satellite in small patches of the sky. In particular, the introduction of the
MHW allows one to detect and subtract the brightest point sources present in
the input data and therefore to improve the reconstructions of the CMB and
foreground components achieved by MEM on its own. In addition, a point source
catalogue at each Planck frequency is produced, which is more complete and
accurate than those obtained by each technique independently.

</DOC>
<DOC>
<DOCNO> 117418 </DOCNO>
Photoionization of Galactic Halo Gas by Old Supernova Remnants


  We present new calculations on the contribution from cooling hot gas to the
photoionization of warm ionized gas in the Galaxy. We show that hot gas in
cooling supernova remnants (SNRs) is an important source of photoionization,
particularly for gas in the halo. We find that in many regions at high latitude
this source is adequate to account for the observed ionization so there is no
need to find ways to transport stellar photons from the disk. The flux from
cooling SNRs sets a floor on the ionization along any line of sight. Our model
flux is also shown to be consistent with the diffuse soft X-ray background and
with soft X-ray observations of external galaxies.
  We consider the ionization of the clouds observed towards the halo star HD
93521, for which there are no O stars close to the line of sight. We show that
the observed ionization can be explained successfully by our model EUV/soft
X-ray flux from cooling hot gas. In particular, we can match the H alpha
intensity, the S++/S+ ratio, and the C+* column. From observations of the
ratios of columns of C+* and either S+ or H0, we are able to estimate the
thermal pressure in the clouds. The slow clouds require high (~10^4 cm^-3 K)
thermal pressures to match the N(C+*)/N(S+) ratio. Additional heating sources
are required for the slow clouds to maintain their ~7000 K temperatures at
these pressures, as found by Reynolds, Hausen & Tufte (1999).

</DOC>
<DOC>
<DOCNO> 99529 </DOCNO>
Model sets: a survey


  This article surveys the mathematics of the cut and project method as applied
to point sets, called here {\em model sets}. It covers the geometric,
arithmetic, and analytical sides of this theory as well as diffraction and the
connection with dynamical systems.

</DOC>
<DOC>
<DOCNO> 67743 </DOCNO>
Reexamination of the Constraint on Topcolor-Assisted Technicolor Models


  Recent study on the charged top-pion correction to R_b shows that it is
negative and large, so that the precision experimental value of R_b gives rise
to a severe constraint on the topcolor-assisted technicolor models such that
the top-pion mass should be of the order of 1 TeV. In this paper, we restudy
this constraint by further taking account the extended technicolor gauge boson
correction which is positive. With this positive contribution to R_b, the
constraint on the topcolor-assisted technicolor models from R_b changes
significantly. The top-pion mass is allowed to be in the region of a few
hundred GeV depending on the models.

</DOC>
<DOC>
<DOCNO> 83474 </DOCNO>
Top-down induction of clustering trees


  An approach to clustering is presented that adapts the basic top-down
induction of decision trees method towards clustering. To this aim, it employs
the principles of instance based learning. The resulting methodology is
implemented in the TIC (Top down Induction of Clustering trees) system for
first order clustering. The TIC system employs the first order logical decision
tree representation of the inductive logic programming system Tilde. Various
experiments with TIC are presented, in both propositional and relational
domains.

</DOC>
<DOC>
<DOCNO> 84370 </DOCNO>
Second post-Newtonian radiative evolution of the relative orientations


  The radiative evolution of the relative orientations of the spin and orbital
angular momentum vectors ${\bf S}_{{\bf 1}}, {\bf S}_{{\bf 2}}$ and ${\bf L}$,
characterizing a binary system on eccentric orbit is studied up to the second
post-Newtonian order. As an intermediate result, all Burke-Thorne type
instantaneous radiative changes in the spins are shown to average out over a
radial period. It is proved that spin-orbit and spin-spin terms contribute to
the radiative angular evolution equations, while Newtonian, first and second
post-Newtonian terms together with the leading order tail terms do not. In
complement to the spin-orbit contribution, given earlier, the spin-spin
contribution is computed and split into two-body and self-interaction parts.
The latter provide the second post-Newtonian order corrections to the 3/2 order
Lense-Thirring description.

</DOC>
<DOC>
<DOCNO> 85013 </DOCNO>
An asymptotic analysis of spherically symmetric perfect fluid


  The asymptotic properties of self-similar spherically symmetric perfect fluid
solutions with equation of state p=alpha mu (-1<alpha<1) are described. We
prove that for large and small values of the similarity variable, z=r/t, all
such solutions must have an asymptotic power-law form. Some of them are
associated with an exact power-law solution, in which case they are
asymptotically Friedmann or asymptotically Kantowski-Sachs for 1>alpha >-1 or
asymptotically static for 1>alpha >0. Others are associated with an approximate
power-law solution, in which case they are asymptotically quasi-static for
1>alpha >0 or asymptotically Minkowski for 1>alpha >1/5. We also show that
there are solutions whose asymptotic behaviour is associated with finite values
of z and which depend upon powers of ln z. These correspond either to a second
family of asymptotically Minkowski solutions for 1>alpha>1/5 or to solutions
that are asymptotically Kasner for 1>alpha>-1/3. There are some other
asymptotic power-law solutions associated with negative alpha, but the physical
significance of these is unclear. The asymptotic form of the solutions is given
in all cases, together with the number of associated parameters.

</DOC>
<DOC>
<DOCNO> 178648 </DOCNO>
Effective Chiral Theory for Radiative Decays of Mesons


  An extended $U(3)_L\bigotimes U(3)_R$ chiral theory which includes
pseudoscalar and vector meson nonets as dynamic degrees of freedom is
presented. We combine a hidden symmetry approach with a general procedure of
including the $\eta'$ meson into chiral theory. The $U(3)_L\bigotimes U(3)_R$
and the SU(3) symmetries are broken by the mechanism based on quark mass
matrix. Meson radiative decay widths are parameterized in terms of a single and
real $\eta-\eta'$ mixing angle $\theta_P$, a U(3)_V symmetry breaking scale
parameter c_W, and the radiative decay constants $F_\pi, F_K, F_\eta,
F_{\eta'}$, for the $\pi, \eta$, K, $\eta '$ mesons, respectively. Taking
$F_\pi = 93 MeV$, a global fit to decay width data yields F_K/F_\pi = 1.16 \pm
0.11,
  F_\eta/F_\pi = 1.14\pm 0.04, F_{\eta'}/F_\pi = 1.09 \pm 0.04, c_W = -0.19
\pm0.03, \theta_P =-(15.4 \pm 1.8)^o.

</DOC>
<DOC>
<DOCNO> 117144 </DOCNO>
External-field shifts of the 199Hg+ optical frequency standard


  Frequency shifts of the ^199Hg^+ 5d^10 6s ^2S_1/2 (F=0, M_F=0) to 5d^9 6s^2
^2D_5/2 (F=2, M_F=0) electric-quadrupole transition at 282 nm due to external
fields are calculated, based on a combination of measured atomic parameters and
ab initio calculations. This transition is under investigation as an optical
frequency standard. The perturbations calculated are the quadratic Zeeman
shift, the scalar and tensor quadratic Stark shifts, and the interaction
between an external electric field gradient and the atomic quadrupole moment.
The quadrupole shift is likely to be the most difficult to evaluate in a
frequency standard and may have a magnitude of about 1 Hz for a single ion in a
Paul trap.

</DOC>
<DOC>
<DOCNO> 11193 </DOCNO>
Phase diagram of mixed system of ferroelectric relaxors in the random


  We suggest a random field based model for calculation of physical properties
of mixed ferroelectric relaxors. Our model naturally incorporates the different
orientations of electric dipoles (related to different solid solution
components) as well as the contribution of nonlinear and correlation effects of
random field. We calculate the transition temperature $T_c$ as well as
concentrational and temperature dependence of order parameters.

</DOC>
<DOC>
<DOCNO> 119157 </DOCNO>
Bubbles from dark energy ?


  In a model recently proposed by Albrecht and Skordis it was suggested that
the observed accelerated expansion of the universe could be caused by a scalar
field which is trapped in a local minimum of an exponential potential modified
by a polynomial prefactor. We show that scalar field cosmologies with this kind
of local minimum in the potential are stable and do not decay to the true
vacuum if they fulfill the observational constraints from the Type Ia
Supernovae experiments. Further we briefly sketch how this potential could be
related to a potential of interacting D-branes.

</DOC>
<DOC>
<DOCNO> 122674 </DOCNO>
Dissecting the luminosity function of the Coma cluster of galaxies by


  By means of wide-field (42x28 arcmin) CCD images of the Coma cluster of
galaxies and of control fields, taken at the Canada-France-Hawaii telescope
with the CFH12K and UH8K cameras, we determine the luminosity function
bi-variate in central brightness. We found a clear progression for a steeping
and weakening of the FL going from high surface brightness galaxies (mu~20$
mag/arcsec2) to galaxies of very-faint central brightnesses (mu 24.5
mag/arcsec2). Compact galaxies, usually rejected in the star/galaxy
classification, are found to be a minor population in Coma. A huge population
of low surface brightness galaxies red and faint are discovered, representing
the largest contributor to the LF at faint magnitudes. Among them, there could
be the remnant of high redshift starbursting galaxies responsible for the
Butcher-Oemler effect.

</DOC>
<DOC>
<DOCNO> 178985 </DOCNO>
Momentum distributions and reaction mechanisms for breakup of


  A theoretical model able to describe fragmentation reactions of three--body
halo nuclei on different targets, from light to heavy, is used to compute
neutron and core momentum distributions. Both Coulomb and nuclear interactions
are simultaneously included. We specify the different reaction mechanisms
related to various processes. The method is applied to fragmentation of $^6$He
and $^{11}$Li on C and Pb. We find good agreement with the available
experimental results.

</DOC>
<DOC>
<DOCNO> 40556 </DOCNO>
Beam Test of BTeV Pixel Detectors


  The silicon pixel vertex detector is one of the key elements of the BTeV
spectrometer. Detector prototypes were tested in a beam at Fermilab. We report
here on the measured spatial resolution as a function of the incident angles
for different sensor-readout electronics combinations. We compare the results
with predictions from our Monte Carlo simulation.

</DOC>
<DOC>
<DOCNO> 123217 </DOCNO>
Further constraints on variation of the fine structure constant from


  Comparison of quasar absorption line spectra with laboratory spectra provides
a precise probe for variability of the fine structure constant, alpha, over
cosmological time-scales. We constrain variation in alpha in 21 Keck/HIRES Si
IV absorption systems using the alkali doublet (AD) method in which changes in
alpha are related to changes in the doublet spacing. The precision obtained
with the AD method has been increased by a factor of 3: da/a = (-0.5 +/- 1.3) *
10^{-5}. We also analyse potential systematic errors in this result. Finally,
we compare the AD method with the many-multiplet method which has achieved an
order of magnitude greater precision and we discuss the future of the AD
method.

</DOC>
<DOC>
<DOCNO> 72300 </DOCNO>
Consequences of the Factorization Hypothesis in pbar p, pp, gamma p and


  Using an eikonal analysis, we examine the validity of the factorization
theorem for nucleon-nucleon, gamma p and gamma gamma collisions. As an example,
using the additive quark model and meson vector dominance, we directly show
that for all energies and values of the eikonal, that the factorization theorem
sigma_{nn}/sigma_{gamma p} = sigma_{gamma p}/sigma_{gamma gamma} holds. We can
also compute the survival probability of large rapidity gaps in high energy
pbar p and pp collisions. We show that the survival probabilities are identical
(at the same energy) for gamma p and gamma gamma collisions, as well as for
nucleon-nucleon collisions. We further show that neither the factorization
theorem nor the reaction-independence of the survival probabilities depends on
the assumption of an additive quark model, but, more generally, depends on the
opacity of the eikonal being independent of whether the reaction is n-n, gamma
p or gamma gamma.

</DOC>
<DOC>
<DOCNO> 84082 </DOCNO>
Frequency-domain P-approximant filters for time-truncated inspiral


  Frequency-domain filters for time-windowed gravitational waves from
inspiralling compact binaries are constructed which combine the excellent
performance of our previously developed time-domain P-approximants with the
analytic convenience of the stationary phase approximation without a serious
loss in event rate. These Fourier-domain representations incorporate the ``edge
oscillations'' due to the (assumed) abrupt shut-off of the time-domain signal
caused by the relativistic plunge at the last stable orbit. These new analytic
approximations, the SPP-approximants, are not only `effectual' for detection
and `faithful' for parameter estimation, but are also computationally
inexpensive to generate (and are `faster' by factors up to 10, as compared to
the corresponding time-domain templates). The SPP approximants should provide
data analysts the Fourier-domain templates for massive black hole binaries of
total mass m less than about 40 solar mases, the most likely sources for LIGO
and VIRGO.

</DOC>
<DOC>
<DOCNO> 102060 </DOCNO>
On the Existence of Finite Type Link Homotopy Invariants


  We show that for links with at most 5 components, the only finite type
homotopy invariants are products of the linking numbers. In contrast, we show
that for links with at least 9 components, there must exist finite type
homotopy invariants which are not products of the linking numbers. This
corrects previous errors of the first author.

</DOC>
<DOC>
<DOCNO> 116856 </DOCNO>
A "hybrid"-type system for an achromatic focusing of ions


  It is known, that at high energies of ions (more than 10 MeV for light ions)
the focusing by magnetic quadrupole fields is most effective, whereas at small
energies (less than 1 MeV) - the focusing by electrical quadrupole fields. At
intermediate energies of ions (from 1 to 10 MeV) the efficiency of each of
these types of a focusing is reduced. The authors offer to utilize for this
purpose the "hybrid" type of focusing systems consisting of sequence of
electrical and magnetic quadrupole lenses, which are localized in the same
space. For making fields of electrical quadrupole lenses it is offered to
utilize RF quadrupoles. The RF electrical quadrupoles are created due to the
relevant configuration of drift tubes in the vicinity of an accelerating gap.
As a result of the general theoretical analysis and calculation of concrete
versions of practical realizations it is shown that the given system has
advantage as contrasted to by known analogs in the field of medium energies.
The velocity band of ions, in which the stable motion is ensured, is
essentially changed, and the focusing becomes "achromatic". The calculations
have been performed for protons with velocities 0.5-1.0 % of light velocity, at
the gradients of electrical field up to 50 kV per square cm, and the gradients
of magnetic field up to 1 T/m. Achromaticity of this system allows to lower a
radiative activation of accelerator and to reduce damage of electrode surfaces
by lost ions.

</DOC>
<DOC>
<DOCNO> 68927 </DOCNO>
Soft pions at high energy and its phenomenological implications


  The soft pion theorem in the inclusive reaction at high energy applied to the
current induced reaction is explained briefly. A characteristic aspect of this
theorem is the charge asymmetry produced by the pole terms in the soft pion
limit. The pion charge asymmetry in the central region in the
target-virtual-photon center of the mass (CM) frame of the semi-inclusive
electroproduction and the contribution to the Gottfried sum are illustrated as
examples.

</DOC>
<DOC>
<DOCNO> 10289 </DOCNO>
Evolution of the Spin Gap Upon Doping a 2-Leg Ladder


  The evolution of the spin gap of a 2-leg ladder upon doping depends upon the
nature of the lowest triplet excitations in a ladder with two holes. Here we
study this evolution using various numerical techniques for a t-t'-J ladder as
the next-near-neighbor hopping t' is varied. We find that depending on the
value of t', the spin gap can evolve continuously or discontinuously and the
lowest triplet state can correspond to a magnon, a bound magnon-hole-pair, or
two separate quasi-particles. Previous experimental results on the
superconducting two-leg ladder Sr12Ca2Cu24O41 are discussed.

</DOC>
<DOC>
<DOCNO> 40532 </DOCNO>
D^0-$\bar D^0$ Mixing and CP Violation from FOCUS Experiment


  Measurement results on $D^0$-$\bar D^0$ mixing and CP violation are
presented. FOCUS, a fixed target experiment at Fermilab, collected a high
statistics photo-produced charm sample collected during the 96-97 run. We
reconstructed more than 1 million charmed particles and compared the lifetimes
of two $D^0$ meson decays to $K^-\pi^+$ and $K^-K^+$. The mixing parameter,
$y_{\rm cp}$, we obtained is $(3.42\pm 1.39\pm 0.74)%$. We also searched CP
asymmetries in $D^+\to K^-K^+\pi^+$, $D^0\to K^-K^+$ and $D^0\to \pi^-\pi^+$
decay modes. We did not see any evidence of CP violation by comparing the decay
rates for particle and antiparticle.

</DOC>
<DOC>
<DOCNO> 69055 </DOCNO>
Dust versus Supernova Cosmology


  Here we present some critical discussions about the systematic uncertainty by
dust extinction in the recent cosmological results of high-redshift Type Ia
supernovae. First we argue that the currently available data do not robustly
exclude the cosmologically significant extinction either by the reddening check
or the dispersion argument because of the observational uncertainties, even in
the case of ordinary dust that reddens. Then we discuss two theoretical
possibilities that high-z supernovae have larger extinction and hence they are
fainter than local supernovae: the intergalactic dust and host galaxy
evolution. Optical and near-infrared observations for a large number of
supernovae with improved photometric accuracy are required to reject these
possibilities and derive a compelling cosmological result.

</DOC>
<DOC>
<DOCNO> 40065 </DOCNO>
New Clock Comparison Tests of Lorentz Symmetry


  We present two new measurements constraining Lorentz and CPT violation using
the Xe-129 / He-3 Zeeman maser and atomic hydrogen masers. Experimental
investigations of Lorentz and CPT symmetry provide important tests of the
framework of the standard model of particle physics and theories of gravity.
The two-species Xe-129 / He-3 Zeeman maser bounds violations of CPT and Lorentz
symmetry of the neutron at the 10^-31 GeV level. Measurements with atomic
hydrogen masers provide a clean limit of CPT and Lorentz symmetry violation of
the proton at the 10^-27 GeV level.

</DOC>
<DOC>
<DOCNO> 123326 </DOCNO>
Optical and X-ray clusters as tracers of the supercluster-void network.


  We study the space distribution of Abell and X-ray selected clusters of
galaxies from the ROSAT Bright Source Catalog, and determine correlation
functions for both cluster samples. On small scales the correlation functions
depend on the cluster environment: clusters in rich superclusters have a larger
correlation length and amplitude than all clusters. On large scales correlation
functions depend on the distribution of superclusters. On these scales
correlation functions for both X-ray and Abell clusters are oscillating with a
period of ~115 h^{-1} Mpc. This property shows the presence of a dominating
scale in the distribution of rich superclusters.

</DOC>
<DOC>
<DOCNO> 10032 </DOCNO>
Exactly solvable su(N) mixed spin ladders


  It is shown that solvable mixed spin ladder models can be constructed from
su(N) permutators. Heisenberg rung interactions appear as chemical potential
terms in the Bethe Ansatz solution. Explicit examples given are a mixed
spin-1/2 spin-1 ladder, a mixed spin-1/2 spin-3/2 ladder and a spin-1 ladder
with biquadratic interactions.

</DOC>
<DOC>
<DOCNO> 122818 </DOCNO>
Extent of Excess Far Infrared Emission around Luminosity Class III Stars


  With the Infrared Space Observatory, we conducted 3x3-pixel imaging
photometry of twelve luminosity class III stars, which were previously presumed
to have dust particles around them, at far infrared wavelengths (60 and 90 um).
Eleven out of twelve targets show a peak of excess (above photosphere) far
infrared emission at the location of the star, implying that the dust particles
are truly associated with stars. To estimate the size of the excess emission
source, the flux ratio of center to boundary pixels of the 3x3 array was
examined. The radius of the dust emission is found to be ~3000 to ~10000 AU for
a thin shell distribution, and ~5000 to ~25000 AU for a uniform distribution.
We consider three models for the origin of the dust: disintegration of comets,
sporadic dust ejection from the star, and emission from nearby interstellar
cirrus. The data seem to rule out the first model (as far as the "Kuiper--belt"
like particles are assumed to be large blackbody grains), but do not enable us
to choose between the other two models.

</DOC>
<DOC>
<DOCNO> 68302 </DOCNO>
Radiative Rare Kaon Decays


  We review some recent theoretical results on radiative rare kaon decays.
Particular attention is devoted to the channels $K\to \pi l\bar{% l}$ and $K\to
\pi \pi \gamma$, where we are (or might be) able to extract the short distance
contributions. This is achieved by a careful study of the long distance part.
We study also CP violating observables, which are sensitive also to extensions
of the SM. As byproduct, we discuss interesting chiral tests.

</DOC>
<DOC>
<DOCNO> 102646 </DOCNO>
Ruled special Lagrangian 3-folds in C^3


  This is the fourth in a series of papers math.DG/0008021, math.DG/0008155,
math.DG/0010036 constructing explicit examples of special Lagrangian
submanifolds (SL m-folds) in C^m. A submanifold of C^m is ruled if it is fibred
by a family of real straight lines in C^m. This paper studies ruled special
Lagrangian 3-folds in C^3, giving both general theory and families of examples.
Our results are related to previous work of Harvey and Lawson, Borisenko and
Bryant.
  An important class of ruled SL 3-folds is the special Lagrangian cones in
C^3. Each ruled SL 3-fold is asymptotic to a unique SL cone. We study the
family of ruled SL 3-folds N asymptotic to a fixed SL cone N_0. We find that
this depends on solving a linear equation, so that the family of such N has the
structure of a vector space. We also show that the intersection Sigma of N_0
with the unit sphere in C^3 is a Riemann surface, and construct a ruled SL
3-fold N asymptotic to N_0 for each holomorphic vector field w on Sigma.
  As corollaries of this we write down two large families of explicit SL
3-folds depending on a holomorphic function on C, which include many new
examples of singularities of SL 3-folds. We also show that each SL T^2 cone N_0
can be extended to a 2-parameter family of ruled SL 3-folds asymptotic to N_0,
and diffeomorphic to T^2 x R.

</DOC>
<DOC>
<DOCNO> 151021 </DOCNO>
Sphalerons, Merons and Unstable Branes in AdS


  We construct unstable classical solutions of Yang-Mills theories and their
dual unstable states of type IIB on AdS_5. An example is the unstable D0-brane
of type IIB located at the center of AdS. This has a field theory dual which is
a sphaleron in gauge theories on S^3 x R. We argue that the two are dual
because both are sphalerons associated to the topology of the
instanton/D-instanton. This agreement provides a non-supersymmetric test of the
AdS/CFT duality. As an illustration, many aspects of Sen's hypothesis regarding
the unstable branes can be seen easily in the weakly coupled dual field theory
description. In Euclidean AdS the D0-branes are dual to gauge theory merons.
This implies that the two ends of a D0-brane world-line carry half the charge
of a D-instanton. Other examples involve unstable strings in the Coulomb phase.

</DOC>
<DOC>
<DOCNO> 11370 </DOCNO>
Local Spin Correlations in Heisenberg Antiferromagnets


  We use linked cluster series expansion methods to estimate the values of
various short distance correlation functions in $S=1/2$ Heisenberg
antiferromagnets at T=0, for dimension $d=1,2,3$. The method incorporates the
possibility of spontaneous symmetry breaking, which is manifest in $d=2,3$. The
results are important in providing a test for approximate theories of the
antiferromagnetic ground state.

</DOC>
<DOC>
<DOCNO> 70530 </DOCNO>
Large Angle MSW Solution in Grand Unified Theories with SU(3) X U(1)


  We construct a model with a SU(3) X U(1) horizontal symmetry in the context
of Grand Unified Theories. In our models, the bi-maximal lepton mixing and
suitable neutrino masses for the large angle MSW solution are obtained without
any fine-tuning due to the spontaneously broken SU(3)_H symmetry. The three
generations of quarks and leptons are unified as members of the SU(3)_H
fundamental representation, and the U(1)_H charge gives the origin of the
fermion mass hierarchy and mixing angles. We present two explicit examples of
SU(5)_GUT and SO(10)_GUT models, in which the Yukawa structures are given
successfully.

</DOC>
<DOC>
<DOCNO> 178726 </DOCNO>
Contrasting N Delta and N N parity-violating asymmetries in nuclei


  Several perspectives that can be opened by studying the electroexcitation of
the delta via parity-violating electron scattering from nuclei are examined,
working within the context of the relativistic Fermi gas model. A strong
enhancement of the left-right asymmetry in the delta sector compared with that
in the quasi-elastic regime is found and the potential to find clear signatures
for the axial-vector contributions of the nucleon-to-delta transition to the
asymmetry identified at specific low momentum transfer kinematics.
Possibilities of probing the deformation of the delta are also explored, and
using both the proton and nuclei as targets, the abilitiy to study the
asymmetry on neutrons is studied.

</DOC>
<DOC>
<DOCNO> 11835 </DOCNO>
Inhomogeneous Broadening of Exciton Lines in Magneto-Optical Reflection


  An approach is proposed to determine parameters of homogeneous and
inhomogeneous broadening for reflection lines of quasi-two-dimensional excitons
in semiconductor quantum well structures. A phenomenological model is developed
taking into account fluctuations of the exciton energy which are expected to
cause inhomogeneous broadening of exciton reflectivity lines. This concept is
applied to magneto-optical studies of CdTe/(Cd,Mg)Te single quantum well
heterostructures containing a two-dimensional electron gas. By the analysis of
excitonic reflection spectra in magnetic fields the parameters of homogeneous
and inhomogeneous broadening of the exciton as well as their temperature
dependencies were obtained.

</DOC>
<DOC>
<DOCNO> 84797 </DOCNO>
Signature for local Mixmaster dynamics in U(1) symmetric cosmologies


  Previous studies \cite{berger98a} have provided strong support for a local,
oscillatory approach to the singularity in U(1) symmetric, spatially
inhomogeneous vacuum cosmologies on $T^3 \times R$. The description of a vacuum
Bianchi type IX, spatially homogeneous Mixmaster cosmology (on $S^3 \times R$)
in terms of the variables used to describe the U(1) symmetric cosmologies
indicates that the oscillations in the latter are in fact those of local
Mixmaster dynamics. One of the variables of the U(1) symmetric models increases
only at the end of a Mixmaster era. Such an increase therefore yields a
qualitative signature for local Mixmaster dynamics in spatially inhomogeneous
cosmologies.

</DOC>
<DOC>
<DOCNO> 9281 </DOCNO>
The electronic structure of CuSiO3 - a possible candidate for a new


  Electronic structure calculations are presented for the well-known CuGeO3 and
the recently discovered isostructural CuSiO3 compounds. The magnitude of the
dispersion in chain direction is considerably smaller for CuSiO3, whereas the
main interchain couplings are rather similar in both compounds. Starting from
extended one-band tight-binding models fitted to the bandstructures, the
exchange integrals were estimated for both compounds in terms of a spatially
anisotropic Heisenberg model. Remarkable frustrating second neighbor couplings
are found both for intra- and inter-chain interactions. A magnetic moment of
about 0.35 Bohr-magneton is predicted for CuSiO3 in the Neel state.

</DOC>
<DOC>
<DOCNO> 40194 </DOCNO>
A study of time-dependent CP-violating asymmetries in B0 -> J/psi K0S


  We present a preliminary measurement of time-dependent CP-violating
asymmetries in B0 -> J/psi K0S and B0 -> psi(2S) K0S decays recorded by the
BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC. The data
sample consists of 9.0 fb-1 collected at the Y(4S) resonance and 0.8 fb-1
off-resonance. One of the neutral B mesons, produced in pairs at the Y(4S), is
fully reconstructed. The flavor of the other neutral B meson is tagged at the
time of its decay, mainly with the charge of identified leptons and kaons. A
neural network tagging algorithm is used to recover events without a clear
lepton or kaon tag. The time difference between the decays is determined by
measuring the distance between the decay vertices. Wrong-tag probabilities and
the time resolution function are measured with samples of fully-reconstructed
semileptonic and hadronic neutral B final states. The value of the asymmetry
amplitude, sin2beta, is determined from a maximum likelihood fit to the time
distribution of 120 tagged B0 -> J/psi K0S and B0 -> psi(2S) K0S candidates to
be sin2beta = 0.12+/-0.37 (stat) +/- 0.09 (syst) (preliminary).

</DOC>
<DOC>
<DOCNO> 8151 </DOCNO>
Gaussian to Exponential Crossover in the Attenuation of Polarization


  An ingenious pulse sequence devised by S. Zhang, B. H. Meier, and R. R. Ernst
(Phys. Rev. Lett. {\bf 69}, 2149 (1992)) reverses the time evolution (``spin
diffusion'') of the local polarization in a dipolar coupled $^{1}$H spin
system. This refocusing originates a Polarization Echo whose amplitude
attenuates by increasing the time $t_R$ elapsed until the dynamics is reversed.
Different functional attenuations are found for a set of dipolar coupled
systems: ferrocene, (C$_5$H$_5$)$_2$Fe, cymantrene, (C$_5$H$_5$)Mn(CO)$_3$, and
cobaltocene, (C$_5$H$_5$)$_2$Co. To control a relevant variable involved in
this attenuation a pulse sequence has been devised to progressively reduce the
dipolar dynamics. Since it reduces the evolution of the polarization echo it is
referred as REPE sequence. Two extreme behaviors were found while
characterizing the materials: In systems with a strong source of relaxation and
slow dynamics, the attenuation follows an exponential law (cymantrene). In
systems with a strong dipolar dynamics the attenuation is mainly Gaussian. By
the application of the REPE sequence the characteristic time of the Gaussian
decay is increased until the presence of an underlying dissipative mechanism is
revealed (cobaltocene). For ferrocene, however, the attenuation remains
Gaussian within the experimental time scale. These two behaviors suggest that
the many body quantum dynamics presents an extreme intrinsic instability which,
in the presence of small perturbations, leads to the onset of irreversibility.
This experimental conclusion is consistent with the tendencies displayed by the
numerical solutions of model systems.

</DOC>
<DOC>
<DOCNO> 68971 </DOCNO>
The Weizsacker-Williams Approximation to Trident Production in


  The appears to exist no detailed calculation of the multiphoton trident
process e + n omega_0 -> e' + e+e-, which can occur during the interaction of
an electron beam with an intense laser beam. We present a calculation in the
Weizsacker-Williams approximation that is in good agreement with QED
calculations for the weak-field case.

</DOC>
<DOC>
<DOCNO> 99286 </DOCNO>
Some properties of index of Lie algebras


  In this paper we prove several theorems about the behavior of index of Lie
algebras derived from associative algebras under tensor products of underlying
associative algebras.

</DOC>
<DOC>
<DOCNO> 9637 </DOCNO>
Macroscopic Quantum Oscillations of Antiferromagnetic Nanoclusters in a


  New macroscopic quantum interference effects in the behavior of the
antiferromagnetic nanoclusters under action of a swept magnetic field are
predicted and theoretically investigated, namely : oscillations of the magnetic
susceptibility of nanocluster similar to the electron Bloch oscillations in
crystal and the corresponding Stark ladder-like resonances in ac-magnetic
field. These effects are related to that of the macroscopic quantum coherence
phenomena. The analogy of the antiferromagnetic nanoclusters quantum behavior
and Josephson junction with a small capacity was revealed as well.

</DOC>
<DOC>
<DOCNO> 10122 </DOCNO>
Damping of collective modes and quasiparticles in d-wave superconductors


  The two-dimensional d-wave superconducting state of the high temperature
superconductors has a number of different elementary excitations: the
spin-singlet Cooper pairs, the spin S=1/2 fermionic quasiparticles, and a
bosonic S=1 resonant collective mode, phi_{alpha}, at the antiferromagnetic
wavevector. Although the phi_{alpha} quanta are strongly coupled to the gapped
quasiparticles near the (pi,0), (0,pi) wavevectors (the "hot spots"), they are
essentially decoupled from the low energy quasiparticles near the nodes of the
superconducting gap. Consequently, distinct and independent low energy quantum
field theories can be constructed for the phi_{alpha} and nodal quasiparticle
excitations. We review recent work introducing a 2+1 dimensional boundary
conformal field theory for the damping of the phi_{alpha} excitations by
non-magnetic impurities, which is built on the proximity to a magnetic ordering
transition at which the phi_{alpha} condense; the results are compared with
neutron scattering experiments. Photoemission and THz conductivity measurements
indicate that the nodal quasiparticles undergo strong inelastic scattering at
low temperatures; we propose that this is due to fluctuations near a quantum
phase transition, and critically analyze candidate order parameters and field
theories.

</DOC>
<DOC>
<DOCNO> 121845 </DOCNO>
Cosmic Mach Number as a Function of Overdensity and Galaxy Age


  We carry out an extensive study of the cosmic Mach number (\mach) on scales
of R=5, 10 and 20h^-1Mpc using an LCDM hydrodynamical simulation. We
particularly put emphasis on the environmental dependence of \mach on
overdensity, galaxy mass, and galaxy age. We start by discussing the difference
in the resulting \mach according to different definitions of \mach and
different methods of calculation. The simulated Mach numbers are slightly lower
than the linear theory predictions even when a non-linear power spectrum was
used in the calculation, reflecting the non-linear evolution in the simulation.
We find that the observed \mach is higher than the simulated mean by more than
2-standard deviations, which suggests either that the Local Group is in a
relatively low-density region or that the true value of \Omega_m is ~ 0.2,
significantly lower than the simulated value of 0.37. We show from our
simulation that the Mach number is a weakly decreasing function of overdensity.
We also investigate the correlations between galaxy age, overdensity and \mach
for two different samples of galaxies --- DWARFs and GIANTs. Older systems
cluster in higher density regions with lower \mach, while younger ones tend to
reside in lower density regions with larger \mach, as expected from the
hierarchical structure formation scenario. However, for DWARFs, the correlation
is weakened by the fact that some of the oldest DWARFs are left over in
low-density regions during the structure formation history. For giant systems,
one expects blue-selected samples to have higher \mach than red-selected ones.
We briefly comment on the effect of the warm dark matter on the expected Mach
number.

</DOC>
<DOC>
<DOCNO> 69964 </DOCNO>
Nucleon Spin Structure Functions


  The review of the nucleon spin structure functions problems is presented. The
perturbative QCD predictions for the small x behaviour of the nucleon spin
structure functions are discussed. The role of the resummation of the ln^2 1/x
terms is emphasized. Predictions for the nonsinglet structure function g_1 in
case of a flat as well as a dynamical input are given. The so called "spin
crisis" on the context of both theoretical and experimental future hopes are
also briefly discussed.

</DOC>
<DOC>
<DOCNO> 116743 </DOCNO>
True Transformations of Spacetime Lengths and Apparent Transformations


  Some of the well-known experiments: the ''muon'' experiment, the
Michelson-Morley type experiments, the Kennedy-Thorndike type experiments and
the Ives-Stilwell type experiments are analyzed using the nonrelativistic
theory, the ''apparent transformations (AT) relativity'' and the ''true
transformations (TT) relativity.'' It is shown that all the experiments (when
they are complete from the ''TT relativity'' viewpoint) are in agreement with
the ''TT relativity'' in which the special relativity is understood as the
theory of a four-dimensional spacetime with the pseudo-Euclidean geometry. It
is also explicitly shown that, in contrast to the usual opinion, the commonly
used ''AT relativity'' does not always agree with experiments. The concept of
sameness of a physical quantity is essential for the distinction between the
two forms of relativity both in the theory and in experiments. The difference
in this concept causes the agreement of the ''TT relativity'' with the
experiments and the disagreement of the ''AT relativity.''

</DOC>
<DOC>
<DOCNO> 70107 </DOCNO>
Is the electric charge conserved in brane world?


  We discuss whether electric charge conservation may not hold in
four-dimensional world in models with infinite extra dimensions, i.e., whether
escape of charged particles from our brane is consistent with effectively
four-dimensional electrodynamics on the brane. We introduce a setup with photon
localized on the brane and show that charge leakage into extra dimension is
allowed within this setup. The electric field induced on the brane by escaping
charge does not obey four-dimensional Maxwell's equations; this field gradually
disappears in a causal way. We also speculate on the possibility of the escape
of colored particles and formation of colorless free quark states on the brane.

</DOC>
<DOC>
<DOCNO> 116794 </DOCNO>
The Jefferson Lab 1 kW IR FEL


  The Jefferson Lab (JLab) IR Demo Free Electron Laser (FEL) has completed
commissioning and is initiating user service. The FEL - a high repetition rate,
low extraction efficiency wiggler-driven optical cavity resonator - produces
over 1 kW of tuneable light on intervals in a 3-6 micron wavelength range. It
is driven by a 35-48 MeV, 5 mA superconducting RF (SRF) based energy-recovering
continuous wave (CW) electron linac. The driver accelerator meets requirements
imposed by low energy, high current, and a demand for stringent beam control at
the wiggler and during energy recovery. These constraints are driven by the
need for six-dimensional phase space management, the existence of deleterious
collective phenomena (space charge, wakefields, beam break-up, and coherent
synchrotron radiation), and interactions between the FEL and the accelerator
RF. We will detail the system design, relate commissioning highlights, and
discuss present performance.

</DOC>
<DOC>
<DOCNO> 117452 </DOCNO>
The multi-phase nature of three intracluster media


  Among the models proposed to account for the new component of diffuse EUV and
soft X-ray emission from clusters of galaxies (first discovered in Virgo) are
two key contestants: the non-thermal scenario which postulates a population of
relativistic electrons undergoing inverse-Compton (IC) interaction with the
cosmic microwave background, and the original conjecture that the radiation is
from a thermal warm gas at a temperature of $\sim$ 10$^{5-6}$ K. Currently a
consensus set of limiting values on cosmological parameters favor the thermal
gas interpretation. We also argued, based on pressure balance within the
intracluster medium (ICM), that the non-thermal approach has formidable
difficulties. Here we describe a spatial analysis of the soft X-ray excess
emission of three clusters (Virgo, A2199, and Coma), using archival ROSAT/PSPC
data, which reveals resolved features of cold intracluster clouds in absorption
spreading over vast distances. Within the sample there is good indication that
the soft excess radial trend (SERT, which qualitatively means a rising
importance of the soft component with cluster radius) is due to a centrally
peaked distribution of cold matter, with Coma having the least effect and no
direct evidence for absorption. The data strongly suggest an intermixed ICM
which contains gas masses at a wide range of temperatures, and the soft excess
is due to a warm intermediate phase.

</DOC>
<DOC>
<DOCNO> 117628 </DOCNO>
Disk-Halo Interaction - I. Three-Dimensional Evolution of the Galactic


  The results of a three-dimensional model for disk-halo interaction are
presented here. The model considers explicitly the input of energy and mass by
isolated a nd correlated supernovae in the disk. Once disrupted by the
explosions, the disk never returns to its initial state. Instead it approaches
a state where a thin HI disk is formed in the Galactic plane overlayed by thick
HI and HII gas disk w ith scale heights of 500 pc and of 1 to 1.5 kpc,
respectively. The upper parts o f the thick HII disk (the diffuse ionized
medium) act as a disk-halo interface a nd its formation and stability are
directly correlated to the supernova rate per unit area in the simulated disk.

</DOC>
<DOC>
<DOCNO> 10861 </DOCNO>
Quasiparticles in a strongly correlated liquid with the fermion


  A model of a strongly correlated electron liquid based on the fermion
condensation (FC) is extended to high-temperature superconductors. Within our
model, the appearance of FC presents a boundary separating the region of a
strongly interacting electron liquid from the region of a strongly correlated
electron liquid. We study the superconductivity of a strongly correlated liquid
and show that under certain conditions, the superconductivity vanishes at
temperatures $T>T_c\simeq T_{node}$, with the superconducting gap being
smoothly transformed into a pseudogap. As the result, the pseudogap occupies
only a part of the Fermi surface. The gapped area shrinks with increasing the
temperature and vanishes at $T=T^*$. The single-particle excitation width is
also studied. The quasiparticle dispersion in systems with FC can be
represented by two straight lines characterized by the respective effective
masses $M^*_{FC}$ and $M^*_L$, and intersecting near the binding energy that is
of the order of the superconducting gap. It is argued that this strong change
of the quasiparticle dispersion at the binding can be enhanced in underdoped
samples because of strengthening the FC influence. The FC phase transition in
the presence of the superconductivity is examined, and it is shown that this
phase transition can be considered as kinetic energy driven.

</DOC>
<DOC>
<DOCNO> 68343 </DOCNO>
A new approach to Ginsparg-Wilson fermions


  We expand the most general lattice Dirac operator D in a basis of simple
operators. The Ginsparg-Wilson equation turns into a system of coupled
quadratic equations for the expansion coefficients. Our expansion of D allows
for a natural cutoff and the remaining quadratic equations can be solved
numerically. The procedure allows to find Dirac operators which obey the
Ginpsparg-Wilson equation with arbitrary precision.

</DOC>
<DOC>
<DOCNO> 70606 </DOCNO>
Maximum And Minimum Dark Matter Detection Cross Sections


  The range of neutralino-proton cross sections for R-parity preserving
supergravity models with GUT scale unification of the gauge coupling constants
is examined. The models considered here are mSUGRA, models with non universal
soft breaking and D-brane models. It is found that the current dark matter
detectors are sampling significant parts of the SUSY parameter space and future
detectors could sample almost the entire space. The special regions of
parameter space that may be inaccessible to future detectors are seen to have a
squark/gluino spectra beyond 1 TeV, but observable at the LHC.

</DOC>
<DOC>
<DOCNO> 70497 </DOCNO>
Comments on Brane World Cosmology


  In this paper we consider some constraints on brane-world cosmologies. In the
first part we analyze different behaviors for the expansion of our universe by
imposing constraints on the speed of sound. In the second part, we study the
nature of matter on the brane world by means of the well-known energy
conditions. We find that the strong energy condition must be completely
violated at late stages of the universe.

</DOC>
<DOC>
<DOCNO> 8318 </DOCNO>
Formation and life-time of memory domains in the dissipative quantum


  We show that in the dissipative quantum model of brain the time-dependence of
the frequencies of the electrical dipole wave quanta leads to the dynamical
organization of the memories in space (i.e. to their localization in more or
less diffused regions of the brain) and in time (i.e. to their longer or
shorter life-time). The life-time and the localization in domains of the memory
states also depend on internal parameters and on the number of links that the
brain establishes with the external world. These results agree with the
physiological observations of the dynamic formation of neural circuitry which
grows as brain develops and relates to external world.

</DOC>
<DOC>
<DOCNO> 39733 </DOCNO>
Further Search for the Decay K^+ --> pi^+ nu nubar


  A search for additional evidence for the rare kaon decay K^+ --> pi^+ nu
nubar has been made with a new data set comparable in sensitivity to the
previous exposure that produced a single event.

</DOC>
<DOC>
<DOCNO> 100385 </DOCNO>
On the Additivity of Entanglement of Formation


  We study whether the entanglement of formation is additive over tensor
products and derive a necessary and sufficient condition for optimality of
vector states that enables us to show additivity in two special cases.

</DOC>
<DOC>
<DOCNO> 11346 </DOCNO>
Symmetry effects and equivalences in lattice models of hydrophobic


  We establish the equivalence of a recently introduced discrete model of the
hydrophobic interaction, as well as its extension to continuous state
variables, with the Ising model in a magnetic field with temperature-dependent
strength. In order to capture the effect of symmetries of the solvent particles
we introduce a generalized multi-state model. We solve this model - which is
not of the Ising type - exactly in one dimension. Our findings suggest that a
small increase in symmetry decreases the amplitude of the solvent-mediated part
of the potential of mean force between solute particles and enhances the
solubility in a very simple fashion. High symmetry decreases also the range of
the attractive potential. This weakening of the hydrophobic effect observed in
the model is in agreement with the notion that the effect is entropic in
origin.

</DOC>
<DOC>
<DOCNO> 99335 </DOCNO>
Une identit\'e remarquable en th\'eorie des partitions


  We prove an identity about partitions, previously conjectured in the study of
shifted Jack polynomials (math.CO/9903020). The proof given is using
$\lambda$-ring techniques. It would be interesting to obtain a bijective proof.

</DOC>
<DOC>
<DOCNO> 150616 </DOCNO>
Higher Spin Symmetries, Star-Product and Relativistic Equations in AdS


  We discuss general properties of the theory of higher spin gauge fields in
$AdS_4$ focusing on the relationship between the star-product origin of the
higher spin symmetries, AdS geometry and the concept of space-time locality. A
full list of conserved higher spin currents in the flat space of arbitrary
dimension is presented.

</DOC>
<DOC>
<DOCNO> 102157 </DOCNO>
Radicals and Plotkin's problem concerning geometrically equivalent


  If G and X are groups and N is a normal subgroup of X, then the G-closure of
N in X is the normal subgroup X^G= bigcap{kerphi|phi:X-> G, with N subseteq
kerphi} of X . In particular, 1^G = R_G X is the G-radical of X. Plotkin calls
two groups G and H geometrically equivalent, written G H, if for any free group
F of finite rank and any normal subgroup N of F the G-closure and the H-closure
of N in F are the same. Quasiidentities are formulas of the form
(bigwedge_{i<=n}w_i=1 -> w =1) for any words w, w_i (i<=n) in a free group.
Generally geometrically equivalent groups satisfy the same quasiidentiies.
Plotkin showed that nilpotent groups G and H satisfy the same quasiidenties if
and only if G and H are geometrically equivalent. Hence he conjectured that
this might hold for any pair of groups. We provide a counterexample.

</DOC>
<DOC>
<DOCNO> 10537 </DOCNO>
Weakly-coupled Hubbard chains at half-filling and Confinement


  We study two (very) weakly-coupled Hubbard chains in the half-filled case,
and especially the situation where the intrachain Mott scale $m$ is much larger
than the bare single-electron interchain hopping $t_{\perp}$. First, we find
that the divergence of the intrachain Umklapp channel at the Mott transition
results in the complete vanishing of the single-electron interchain hopping:
This is significant of a strong confinement of coherence along the chains.
Excitations are usual charge fermionic solitons and spinon pairs of the
Heisenberg chain. Then, we show rigorously how the tunneling of spinon-pairs
produces a magnetic interchain exchange $J_{\perp}={t_{\perp}}^2/m>0$. The
result is an insulating state with spin-gapped excitations as in the
delocalized limit (i.e. for rather large interchain hoppings), where the
two-leg ladder is in the well-known D-Mott phase. Unlike for Bechgaard salts,
the confinement/deconfinement transition at absolute zero is here a simple
crossover: no metallic phase is found in undoped two-leg ladders. This
statement might be generalized for N-leg ladders with N=3,4... (but not too
large).

</DOC>
<DOC>
<DOCNO> 40275 </DOCNO>
The Charge Distribution on the Cathode of a Straw Tube Chamber


  We use Green's reciprocation theorem and the method of weighting fields to
deduce the charge distribution on the cathode of a straw tube proportional
chamber. The time dependence of the associated current is also discussed.

</DOC>
<DOC>
<DOCNO> 151197 </DOCNO>
Quantised bulk fields in the Randall-Sundrum compactification model


  The quantisation of a scalar field in the five-dimensional model suggested by
Randall and Sundrum is considered. Using the Kaluza-Klein reduction of the
scalar field, discussed by Goldberger and Wise, we sum the infinite tower of
modes to find the vacuum energy density. Dimensional regularisation is used and
we compute the pole term needed for renormalisation, as well as the finite part
of the energy density. Some comments are made concerning the possible
self-consistent determination of the radius.

</DOC>
<DOC>
<DOCNO> 169830 </DOCNO>
Universal construction of quantum computational networks in


  Any quantum computational network can be constructed with a sequence of the
two-qubit diagonal quantum gates and one-qubit gates in two-state quantum
systems. The universal construction of these quantum gates in the quantum
systems and of the quantum computational networks with these gates may be
achieved with the help of the operator algebra structure of Hamiltonians of the
systems and the properties of the multiple-quantum operator algebra subspaces
of the Liouville operator space and the specific properties of the quantum
algorithm corresponding to the quantum network. As an example, the two-qubit
diagonal gates are exactly prepared in detail in superconducting Josephson
junctions.

</DOC>
<DOC>
<DOCNO> 151618 </DOCNO>
Branes in external field or more about Randall-Sundrum scenario


  Fate of branes in external fields is reviewed with emphasis on a spontaneous
creation of the Brane World. No negative tension brane is involved.

</DOC>
<DOC>
<DOCNO> 99925 </DOCNO>
On Certain Two Dimensional Integrals that Appear In Conformal Field


  In a first part, we generalize a theorem for an holomorphic $\times $
anti-holomorphic integrand, in the case of 2 dimensional Fourier transform. In
the second part, we derive p-uple conformal integrals the integrand of which
are linear combination of holomorphic times holomorphic generalized
hypergeometric functions. The specific case $p=3$ is relevant to determine the
triple Pomeron vertex in QCD.

</DOC>
<DOC>
<DOCNO> 151755 </DOCNO>
Fate of Chiral Symmetries in Supersymmetric Quantum Chromodynamics


  In supersymmetric quantum chromodynamics with N_c-colors and N_f-flavors of
quarks, our effective superpotential provides the alternative description to
the Seiberg's N=1 duality at least for N_f>=N_c+2, where spontaneous breakdown
of chiral symmetries leads to SU(N_c)_{L+R}xSU(N_f-N_c)_LXSU(N_f-N_c)_R as a
nonabelian chiral symmetry. The anomaly-matching is ensured by the presence of
Nambu-Goldstone superfields associated with this breaking and the instanton
contributions are properly equipped in the effective superpotential.

</DOC>
<DOC>
<DOCNO> 120640 </DOCNO>
The distance modulus of the Small Magellanic Cloud based on double-mode


  We employ the very recent photometric data of the OGLE project together with
stellar atmosphere and linear pulsation models to determine the distance
modulus of the Small Magellanic Cloud from its double-mode Cepheids. Based on
the requirement of obtaining the same distance modulus DM from the two types of
variables (fundamental & first overtone and first & second overtone), we get
DM=19.05 mag, with a very small statistical error (standard deviation) of 0.017
mag. Various systematic and zero point ambiguities (primarily those of the
color - temperature transformation) lead to an error of +/-0.13 mag (estimated
3 sigma deviation). This result is in very good agreement with the distance
modulus of the Large Magellanic Cloud of 18.5 mag, derived earlier from cluster
double-mode RR Lyrae stars.

</DOC>
<DOC>
<DOCNO> 122244 </DOCNO>
Nucleosynthesis in massive stars revisited


  We have performed the first calculations to follow the evolution of all
stable nuclei and their radioactive progenitors in a finely-zoned stellar model
computed from the onset of central hydrogen burning through explosion as a Type
II supernova. Calculations were done for 15, 20, and 25 solar masses Pop I
stars using the most recently available set of experimental and theoretical
nuclear data, revised opacity tables, and taking into account mass loss due to
stellar winds. Here results are presented for one 15 solar masses model.

</DOC>
<DOC>
<DOCNO> 119415 </DOCNO>
A Search for OH Megamasers at z > 0.1. I. Preliminary Results


  We present the preliminary results of a survey for OH megamasers underway at
the Arecibo Observatory. The goals of the survey are to calibrate the
luminosity function of OH megamasers to the low-redshift galaxy merger rate
(0.1 < z < 0.2), and to use the enhanced sample of OH megamasers provided by
the survey to study OH megamaser environments, engines, lifetimes, and
structure. The survey should double the known OH megamaser sample to roughly
100 objects. Survey results will be presented in installments to facilitate
community access to the data. Here we report the discovery of 11 OH megamasers
and one OH absorber, and include upper limits on the isotropic 1667 MHz OH line
luminosity of 53 other luminous infrared galaxies at z > 0.1. The new
megamasers show a wide range of spectral properties, but are consistent with
the extant set of 55 previously reported objects, only 8 of which have z > 0.1.

</DOC>
<DOC>
<DOCNO> 122923 </DOCNO>
Chandra--ASCA--RXTE observations of the micro-quasar GRS 1915+105


  A Chandra AO1 30ks HETGS observation of the X-ray transient micro-quasar GRS
1915+105 reveals absorption edges and faint line emission over the HETG energy
range. We find from a preliminary analysis evidence for prominent neutral K
edges associated with iron, silicon, magnesium, and tentatively sulphur. The
column densities assuming solar abundances are consistent with ~ few x $10^{22}
cm^{-2}$ in excess of the Galactic value, and may point to surrounding cold
material associated with GRS 1915+105. Neutral Fe K$\alpha$ emission, and
ionized absorption from Fe XXV and Fe XXVI are resolved. We limit our
discussion to the Chandra results.

</DOC>
<DOC>
<DOCNO> 80823 </DOCNO>
Non-perturbative results for the coefficients b_m and b_a-b_p in O(a)


  We determine the improvement coefficients b_m and b_a-bp in quenched lattice
QCD for a range of beta-values, which is relevant for current large scale
simulations. At fixed beta, the results are rather sensitive to the precise
choices of parameters. We therefore impose improvement conditions at constant
renormalized parameters, and the coefficients are then obtained as smooth
functions of g_0^2. Other improvement conditions yield a different functional
dependence, but the difference between the coefficients vanishes with a rate
proportional to the lattice spacing. We verify this theoretical expectation in
a few examples and are therefore confident that O(a) improvement is achieved
for physical quantities. As a byproduct of our analysis we also obtain the
finite renormalization constant which relates the subtracted bare quark mass to
the bare PCAC mass.

</DOC>
<DOC>
<DOCNO> 68188 </DOCNO>
The minimum width condition for neutrino conversion in matter


  We find that for small vacuum mixing angle $\theta$ and low energies ($s\ll
M^2_Z$) the width of matter, $d_{1/2}$, needed to have conversion probability
$P\geq 1/2$ should be larger than $d_{min}= \pi/(2\sqrt{2} G_{F} \tan 2
\theta)$: $d_{1/2}\geq d_{min}$. Here $G_F$ is the Fermi constant, $s$ is the
total energy squared in the center of mass and $M_Z$ is the mass of the $Z$
boson. The absolute minimum $d_{1/2}=d_{min}$ is realized for oscillations in a
uniform medium with resonance density. For all the other density distributions
(monotonically varying density, castle wall profile, etc.) the required width
$d_{1/2}$ is larger than $d_{min}$. The width $d_{min}$ depends on $s$, and for
$Z$-resonance channels at $s\sim M^2_Z$ we get that $d_{min}(s)$ is 20 times
smaller than the low energy value. We apply the minimum width condition, $d\geq
d_{min}$, to high energy neutrinos in matter as well as in neutrino background.
Using this condition, we conclude that the matter effect is negligible for
neutrinos propagating in AGN and GRBs environments. Significant conversion can
be expected for neutrinos crossing dark matter halos of clusters of galaxies
and for neutrinos produced by cosmologically distant sources and propagating in
the universe.

</DOC>
<DOC>
<DOCNO> 118354 </DOCNO>
Silicate emission in Orion


  We present mid-infrared spectro-imagery and high-resolution spectroscopy of
the Orion bar and of a region in the Orion nebula. These observations have been
obtained in the Guaranteed Time with the Circular Variable Filters of the ISO
camera (CAM-CVF) and with the Short Wavelength Spectrometer (SWS), on board the
European Infrared Space Observatory (ISO). Our data shows emission from
amorphous silicate grains from the entire HII region and around the isolated
O9.5V star Theta2 Ori A. The observed spectra can be reproduced by a mixture of
interstellar silicate and carbon grains heated by the radiation of the hot
stars present in the region. Crystalline silicates are also observed in the
Orion nebula and suspected around Theta2 Ori A. They are probably of
interstellar origin. The ionization structure and the distribution of the
carriers of the Aromatic Infrared Bands (AIBs) are briefly discussed on the
basis of the ISO observations.

</DOC>
<DOC>
<DOCNO> 14066 </DOCNO>
Transition from anomalous to normal hysteresis in a system of coupled


  We address a recently introduced model describing a system of periodically
coupled nonlinear phase oscillators submitted to multiplicative white noises,
wherein a ratchet-like transport mechanism arises through a symmetry-breaking
noise-induced nonequilibrium phase transition. Numerical simulations of this
system reveal amazing novel features such as negative zero-bias conductance and
anomalous hysteresis, explained resorting to a strong-coupling analysis in the
thermodynamic limit. Using an explicit mean-field approximation we explore the
whole ordered phase finding a transition from anomalous to normal hysteresis
inside this phase, estimating its locus and identifying (within this scheme) a
mechanism whereby it takes place.

</DOC>
<DOC>
<DOCNO> 8480 </DOCNO>
Cryptoferromagnetic state in superconductor-ferromagnet multilayers


  We study a possibility of a non-homogeneous magnetic order
(cryptoferromagnetic state) in heterostructures consisting of a bulk
superconductor and a ferromagnetic thin layer that can be due to the influence
of the superconductor. The exchange field in the ferromagnet may be strong and
exceed the inverse mean free time. A new approach based on solving the
Eilenberger equations in the ferromagnet and the Usadel equations in the
superconductor is developed. We derive a phase diagram between the
cryptoferromagnetic and ferromagnetic states and discuss the possibility of an
experimental observation of the CF state in different materials.

</DOC>
<DOC>
<DOCNO> 8553 </DOCNO>
Thermodynamic and diamagnetic properties of weakly doped


  Finite-temperature properties of weakly doped antiferromagnets as modeled by
the two-dimensional t-J model and relevant to underdoped cuprates are
investigated by numerical studies of small model systems at low doping. Two
numerical methods are used: the worldline quantum Monte Carlo method with a
loop cluster algorithm and the finite-temperature Lanczos method, yielding
consistent results. Thermodynamic quantities: specific heat, entropy and spin
susceptibility reveal a sizeable perturbation induced by holes introduced into
a magnetic insulator, as well as a pronounced temperature dependence. The
diamagnetic susceptibility introduced by coupling of the magnetic field to the
orbital current reveals an anomalous temperature dependence, changing character
from diamagnetic to paramagnetic at intermediate temperatures.

</DOC>
<DOC>
<DOCNO> 178783 </DOCNO>
Central Nucleon-Nucleon Potential and Chiral Scalar Form Factor


  The central two-pion exchange NN potential at large distances is studied in
the framework of relativistic chiral symmetry and related directly to the
nucleon scalar form factor, which describes the mass density of its pion cloud.
This relationship is well supported by phenomenology and allows the dependence
of the asymptotic potential on the nucleon mass to be assessed. Results in the
heavy baryon limit are about 25% larger than those corresponding to the
empirical nucleon mass in the region of physical interest. This indicates that
it is very important to keep this mass finite in precise descriptions of the NN
system and supports the efficacy of the relativistic chiral framework. One also
estimates the contribution of subleading effects and presents a simple
discussions of the role of the quark condensate in this problem.

</DOC>
<DOC>
<DOCNO> 116903 </DOCNO>
Analyses of klystron modulator approaches for NLC


  Analyze of experimental results shows that the energy discharge efficiency of
the modern modulators is 0.92-0.93. The energy transfer efficiency can be
reached up to 0.7 for 1.5 usec pulse width and up to 0.8 for 3.0 usec
accordingly. The geometry and core material of the transformer is one element
of modulator, which limits the efficiency due to limitation if transmission
band of the pulse power. Ways of the rise of energy transfer efficiency had
been discussed. The use of features of coupled transmission lines lies in the
base of an idea how the energy transfer efficiency can be improved up to 0.85
in the frame of the conventional approach. In the second part of the paper the
transformerless modulator approaches are presented upon a modified Marx method
of voltage multiplication using on/off IGBT instead of on switches.

</DOC>
<DOC>
<DOCNO> 84344 </DOCNO>
The big bang as a higher-dimensional shock wave


  We give an exact solution of the five-dimensional field equations which
describes a shock wave moving in time and the extra (Kaluza-Klein) coordinate.
The matter in four-dimensional spacetime is a cosmology with good physical
properties. The solution suggests to us that the 4D big bang was a 5D shock
wave.

</DOC>
<DOC>
<DOCNO> 40640 </DOCNO>
High-p_T Jets in pbarp Collisions at sqrt{s} = 630 and 1800 GeV


  Results are presented from analyses of jet data produced in pbarp collisions
at sqrt{s} = 630 and 1800 GeV collected with the DO detector during the 1994-95
Fermilab Tevatron Collider run. We discuss details of detector calibration, and
jet selection criteria in measurements of various jet production cross sections
at sqrt{s} = 630 and 1800 GeV. The inclusive jet cross sections, the dijet mass
spectrum, the dijet angular distributions, and the ratio of inclusive jet cross
sections at sqrt{s} = 630 and 1800 GeV are compared to next-to-leading-order
QCD predictions. The order alpha_s^3 calculations are in good agreement with
the data. We also use the data at sqrt{s} = 1800 GeV to rule out models of
quark compositeness with a contact interaction scale less than 2.2 TeV at the
95% confidence level.

</DOC>
<DOC>
<DOCNO> 9567 </DOCNO>
Rigorous Schrieffer-Wolff transformation for the Anderson impurity model


  With the help of computer algebra, I devise an exact unitary transformation
for the Anderson impurity model which allows to kill the hybridization term in
the slightly simplified case of zero chemical potential. Then I compute
explicitly the outcome of this transformation. This is a rigorous version of
the well known Schrieffer-Wolff transformation. It should be possible to treat
the general case at the price of increased computation time.

</DOC>
<DOC>
<DOCNO> 13320 </DOCNO>
Frequently Asked Questions about Decoherence


  We give a short, critical review of the issue of decoherence. We establish
the most general framework in which decoherence can be discussed, how it can be
quantified and how it can be measured. We focus on environment induced
decoherence and its degree of usefulness for the interpretation of quantum
theory. We finally discuss the emergence of a classical world. An overall
emphasis is given in pointing at common fallacies and misconceptions.

</DOC>
<DOC>
<DOCNO> 118878 </DOCNO>
The Compton Microscope: Using the Energy Dependence of QPO Amplitudes to


  We report the development of a new tool to determine the origin of
quasi-periodic oscillations (QPOs) in accretion disk systems. The technique
uses the source energy spectrum and the energy dependence of the QPO fractional
amplitude to restrict the location of the emission region of the modulated
photons, which are assumed to originate in the inner accretion disk. Both Monte
Carlo and semi-analytical methods are presented. We assume the accretion disk
is enshrouded by a slab atmosphere of hot electrons in which unsaturated
Compton scattering produces the high-energy spectrum. Properties of the
atmosphere, in particular the electron temperature, are assumed functions of
radius from the central compact object. We show that our model reproduces the
observed energy dependence of the fractional amplitude of the 67 Hz QPO in GRS
1915+105 if the QPO is assumed to originate within five gravitational radii
from the innermost stable circular orbit.

</DOC>
<DOC>
<DOCNO> 80729 </DOCNO>
Probing the QCD vacuum with flavour singlet objects: $\eta'$ on the


  We present a study on the direct determination of the $\eta '$ mass on the
full set of SESAM and T$\chi$L QCD vacuum configurations with 2 active flavours
of Wilson fermions, at $\beta = 5.6$. We observe a definite dependency of the
two-loop correlator on the topological charge sector.

</DOC>
<DOC>
<DOCNO> 100843 </DOCNO>
Quantum Mechanics on the Hypercube


  We construct quantum evolution operators on the space of states, that is
represented by the vertices of the n-dimensional unit hypercube. They realize
the metaplectic representation of the modular group SL(2,Z(2^n)). By
construction this representation acts in a natural way on the coordinates of
the non-commutative 2-torus,T^2, and thus is relevant for noncommutative field
theories as well as theories of quantum space-time.

</DOC>
<DOC>
<DOCNO> 71968 </DOCNO>
A light Higgs Boson would invite Supersymmmetry


  If the Higgs boson weighs about 115 GeV, the effective potential of the
Standard Model becomes unstable above a scale of about 10^6 GeV. This
instability may be rectified only by new bosonic particles such as stop
squarks. However, avoiding the instability requires fine-tuning of the model
couplings, in particular if the theory is not to become non-perturbative before
the Planck scale. Such fine-tuning is automatic in a supersymmetric model, but
is lost if there are no Higgsinos. A light Higgs boson would be prima facie
evidence for supersymmetry in the top-quark and Higgs sectors.

</DOC>
<DOC>
<DOCNO> 170730 </DOCNO>
Optimal cloning of coherent states with a linear amplifier and beam


  A transformation achieving the optimal symmetric N-to-M cloning of coherent
states is presented. Its implementation only requires a phase-insensitive
linear amplifier and a network of beam splitters. An experimental demonstration
of this continuous-variable cloner should therefore be in the scope of current
technology. The link between optimal quantum cloning and optimal amplification
of quantum states is also pointed out.

</DOC>
<DOC>
<DOCNO> 83295 </DOCNO>
Boosting Applied to Word Sense Disambiguation


  In this paper Schapire and Singer's AdaBoost.MH boosting algorithm is applied
to the Word Sense Disambiguation (WSD) problem. Initial experiments on a set of
15 selected polysemous words show that the boosting approach surpasses Naive
Bayes and Exemplar-based approaches, which represent state-of-the-art accuracy
on supervised WSD. In order to make boosting practical for a real learning
domain of thousands of words, several ways of accelerating the algorithm by
reducing the feature space are studied. The best variant, which we call
LazyBoosting, is tested on the largest sense-tagged corpus available containing
192,800 examples of the 191 most frequent and ambiguous English words. Again,
boosting compares favourably to the other benchmark algorithms.

</DOC>
<DOC>
<DOCNO> 121778 </DOCNO>
Resolving Sirius-like binaries with the Hubble Space Telescope


  We have imaged seventeen recently discovered Sirius-like binary systems with
HST/WFPC2 and resolved the white dwarf secondary in eight cases. Most of the
implied orbital periods are of order several hundred years, but in three cases
(56 Per, Zeta Cygni and REJ1925-566) the periods are short enough that it may
be possible to detect orbital motion within a few years. It will then be
possible to derive dynamically determined masses for the white dwarfs, and
potentially these stars could be used as stringent tests of the mass-radius
relation and initial-final mass relation.

</DOC>
<DOC>
<DOCNO> 120010 </DOCNO>
Three-dimensional structure of an alpha accretion disk


  An analytic solution is presented to the three-dimensional problem of steady
axisymmetric fluid flow through an accretion disk. The solution has been
obtained through a systematic expansion in the small parameter epsilon =H/R
(the ratio of disk thickness to its radial dimension) of the equations of
viscous hydrodynamics. The equation of state was assumed to be polytropic. For
all values alpha< 0.685 of the viscosity parameter, we find significant
backflow in the midplane of the disk occuring at all radii larger than a
certain value; however, in the inner regions of the disk the fluid always flows
toward the accreting object. The region of backflow is separated from the
region of inflow by a surface flaring outwards from a circular locus of
stagnation points situated in the midplane of the disk.

</DOC>
<DOC>
<DOCNO> 71931 </DOCNO>
Single charged Higgs boson production at next generation linear


  We study the single production of charged Higgs bosons in e+e- collisions,
chiefly in the Minimal Supersymmetric Standard Model. Our analysis complements
foregoing studies of the pair production channel especially in regions where
the kinematic constraint suppresses pair production. We present cross sections
relevant to experiments at the next generation linear colliders and some brief
discussions of their phenomenology. Our analysis shows that the single
production is a useful alternative channel for studying the phenomenology of
charged Higgs bosons, and there are regions of parameter space where it is
accessible beyond the kinematic limit for pair production.

</DOC>
<DOC>
<DOCNO> 100681 </DOCNO>
SO(3) invariants of Seifert manifolds and their algebraic integrality


  For Seifert manifold $M=X({p_1}/_{\f{q_1}},{p_2}/_{\f{q_2}}, ...,{p_n}/_
{\f{q_n}}), \tau^{'}_r(M)$ is calculated for all $r$ odd $\geq 3$. If $r$ is
coprime to at least $n-2$ of $p_k$ (e.g. when $M$ is the Poincare homology
sphere), it is proved that $(\sqrt {\dfrac{4}{r}}\sin
\dfrac{\pi}{r})^{\nu}\tau^{'}_r(M)$ is an algebraic integer in the r-th
cyclotomic field, where $\nu$ is the first Betti number of $M$. For the torus
bundle obtained from trefoil knot with framing 0, i.e.
$X_{tref}(0)=X(-2/_{\f{1}},3/_{\f{1}},6/_{\f{1}}), \tau^{'}_r$ is obtained in a
simple form if $3\mid\llap /r$, which shows in some sense that it is impossible
to generalize Ohtsuki's invariant to 3-manifolds being not rational homology
spheres.

</DOC>
<DOC>
<DOCNO> 101400 </DOCNO>
Complex numbers in three dimensions


  A system of commutative hypercomplex numbers of the form w=x+hy+kz are
introduced in 3 dimensions, the variables x, y and z being real numbers. The
multiplication rules for the complex units h, k are h^2=k, k^2=h, hk=1. The
operations of addition and multiplication of the tricomplex numbers introduced
in this paper have a simple geometric interpretation based on the modulus d,
amplitude \rho, polar angle \theta and azimuthal angle \phi. Exponential and
trigonometric forms are obtained for the tricomplex numbers, depending on the
variables d, \rho, \theta and \phi. The tricomplex functions defined by series
of powers are analytic, and the partial derivatives of the components of the
tricomplex functions are closely related. The integrals of tricomplex functions
are independent of path in regions where the functions are regular. The fact
that the exponential form of the tricomplex numbers contains the cyclic
variable \phi leads to the concepts of pole and residue for integrals of
tricomplex functions on closed paths. The polynomials of tricomplex variables
can be written as products of linear or quadratic factors.

</DOC>
<DOC>
<DOCNO> 80815 </DOCNO>
Vortex configurations in SO(3) \times Z(2)


  We study the configuration space of the Tomboulis $SO(3) \times Z(2)$
formulation with periodic boundary conditions. The dynamical variables are
constrained by the required coincidence of Z(2) and SO(3) monopoles.
Furthermore, there is an additional constraint coming from the boundary
conditions. We propose an update algorithm that satisfies the constraints and
is straightforward to implement.

</DOC>
<DOC>
<DOCNO> 99739 </DOCNO>
Homotopy Algebras for Operads


  We present a definition of homotopy algebra for an operad, and explore its
consequences.
  The paper should be accessible to topologists, category theorists, and anyone
acquainted with operads. After a review of operads and monoidal categories, the
definition of homotopy algebra is given. Specifically, suppose that M is a
monoidal category in which it makes sense to talk about algebras for some
operad P. Then our definition says what a homotopy P-algebra in M is, provided
only that some of the morphisms in M have been marked out as `homotopy
equivalences'.
  The bulk of the paper consists of examples of homotopy algebras. We show that
any loop space is a homotopy monoid, and, in fact, that any n-fold loop space
is an n-fold homotopy monoid in an appropriate sense. We try to compare
weakened algebraic structures such as A_infinity-spaces, A_infinity-algebras
and non-strict monoidal categories to our homotopy algebras, with varying
degrees of success. We also prove results on `change of base', e.g. that the
classifying space of a homotopy monoidal category is a homotopy topological
monoid. Finally, we reflect on the advantages and disadvantages of our
definition, and on how the definition really ought to be replaced by a more
subtle infinity-categorical version.

</DOC>
<DOC>
<DOCNO> 71691 </DOCNO>
Spiral Multi-component Structure in Pade - Approximant QCD


  We present a graphical method of analyzing the infra-red fixed point
structure of Pade approximant QCD. The analysis shows a spiral multi-component
couplant structure as well as an infra-red attractor behavior of PQCD couplant
for all flavors $0 \le N_{f} \le 16$.

</DOC>
<DOC>
<DOCNO> 69978 </DOCNO>
Factorization Scheme and Parton Distributions in the Polarized Virtual


  We investigate spin-dependent parton distributions in the polarized virtual
photon target in perturbative QCD up to the next-to-leading order (NLO). In the
case $\Lambda^2 \ll P^2 \ll Q^2$, where $-Q^2$ ($-P^2$) is the mass squared of
the probe (target) photon, parton distributions can be predicted completely up
to NLO, but they are factorization-scheme-dependent.We analyze parton
distributions in six different factorization schemes and discuss their scheme
dependence. We study, in particular, the QCD and QED axial anomaly effects on
the first moments of parton distributions to see the interplay between the
axial anomalies and factorization schemes. We also show that the
factorization-scheme dependence is characterized by the large-$x$ behaviors of
quark distributions in the virtual photon. Gluon distribution is predicted to
be the same up to NLO among the six factorization schemes examined. In
particular, the first moment of gluon distribution is found to be
factorization-scheme independent up to NLO.

</DOC>
<DOC>
<DOCNO> 68137 </DOCNO>
Microscopic study of energy and centrality dependence of transverse


  The centrality dependence of directed and elliptic flow in light and heavy
systems of colliding nuclei is studied within two microscopic transport models
at energies from 1 AGeV to 160 A GeV. The pion directed flow has negative slope
in the midrapidity range irrespective of bombarding energy and mass number of
the colliding ions. In contrast, the directed flow of nucleons vanishes and
even develops antiflow in the midrapidity range in (semi)peripheral collisions
at energies around 11.6 A GeV and higher. The origin of the disappearance of
flow is linked to nuclear shadowing. Since the effect is stronger for a light
system, it can be distinguished from the similar phenomenon caused by the
quark-gluon plasma formation. In the latter case the disappearance of the flow
due to the softening of the equation of state should be most pronounced in
collisions of heavy ions. The centrality dependence of the elliptic flow shows
that the maximum in the <v_2(b)> distribution is shifted to very peripheral
events with rising incident energy, in accord with experimental data. This is
an indication of the transition from baryonic to mesonic degrees of freedom in
hot hadronic matter.

</DOC>
<DOC>
<DOCNO> 68177 </DOCNO>
WGamma and ZGamma production at Hadron Colliders


  We present a general purpose Monte Carlo program for the calculation of any
infrared safe observable in WGamma and ZGamma production at hadron colliders at
next-to-leading order in alpha_s. We treat the leptonic decays of the W and
Z-boson in the narrow-width approximation, but retain all spin information via
decay angle correlations. The effect of anomalous triple gauge boson couplings
is investigated and we give the analytical expressions for the corresponding
amplitudes. Furthermore, we propose a way to study the effect of anomalous
couplings without introducing the ambiguity of form factors.

</DOC>
<DOC>
<DOCNO> 101335 </DOCNO>
Double Rational Normal Curves with Linear Syzygies


  One describes those double structures on rational normal curves which are
defined scheme theoretically by quadratic equations and have linear syzygies,
generalizing this way the double line in the plane

</DOC>
<DOC>
<DOCNO> 100802 </DOCNO>
A Note on Closed Geodesics for a Class of non-compact Riemannian


  We prove the existence of multiple closed geodesics on non-compact cylindrica
manifolds.

</DOC>
<DOC>
<DOCNO> 13208 </DOCNO>
Spin wave dispersion softening in the ferromagnetic Kondo lattice model


  Spin dynamics is calculated in the ferromagnetic (FM) state of the
generalized Kondo lattice model taking into account strong on-site correlations
between e_g electrons and antiferromagnetic (AFM) exchange among t_{2g} spins.
Our study suggests that competing FM double-exchange and AFM super-exchange
interaction lead to a rather nontrivial spin-wave spectrum. While spin
excitations have a conventional Dq^2 spectrum in the long-wavelength limit,
there is a strong deviation from the spin-wave spectrum of the isotropic
Heisenberg model close to the zone boundary. The relevance of our results to
the experimental data are discussed.

</DOC>
<DOC>
<DOCNO> 80869 </DOCNO>
QCD topology using scale controlled cooling: Densities and cooling


  We aim at reducing the uncertainties inherent in the analysis of the
topological structure by using scale controlled smoothing and observables
independent on the "microscopic" description of the instanton ensemble.

</DOC>
<DOC>
<DOCNO> 39804 </DOCNO>
The Proton Spin Puzzle: A Status Report


  The proton spin puzzle inspired by the EMC experiment and its present status
are closely examined. Recent experimental progress is reviewed. Various
factorization schemes due to the ambiguity arising from the axial anomaly are
discussed. Some misconceptions in the literature about the $\MS$ factorization
scheme are clarified. It is stressed that the polarized nucleon structure
function $g_1(x)$ is independent of the factorization scheme chosen in defining
the quark spin density. Consequently, the anomalous gluon and sea-quark
interpretations for the deviation of the observed first moment of $g_1^p(x)$
from the Ellis-Jaffe sum rule are equivalent. While it is well known that the
total quark spin in the chiral-invariant (CI) factorization scheme (e.g. the
improved parton model) can be made to be close to the quark model expectation
provided that the gluon spin is positive and large enough, it is much less
known that, contrary to the gauge-invariant scheme (e.g. the MSbar scheme), the
quark orbital angular momentum in the CI scheme deviates even farther from the
relativistic quark model prediction. Recent developments in the NLO analysis of
polarized DIS data, orbital angular momentum and lattice calculations of the
proton spin content are briefly sketched.

</DOC>
<DOC>
<DOCNO> 122152 </DOCNO>
Simulations of Stellar Core Collapse, Bounce, and Postbounce Evolution


  In this paper, we present results from a simulation of stellar core collapse,
bounce, and postbounce evolution with Boltzmann neutrino transport. We motivate
the development of our Boltzmann solver in light of the sensitivity of the
neutrino-heating core collapse supernova paradigm to details in the neutrino
transport, particularly near the neutrinospheres, where the neutrinos are
neither diffusing nor free streaming and a kinetic description is necessary,
and in light of the mixed outcomes and transport approximations used in all
prior supernova models in both one and two dimensions. We discuss the
implications of our findings for the supernova mechanism and future supernova
research. We also present the results of a Boltzmann transport prediction of
the early neutrino light curves in the model included here.

</DOC>
<DOC>
<DOCNO> 70179 </DOCNO>
The superfluidity of fermions coupled to gravity


  We investigate superfluidity of the relativistic fermi-gas with gravitational
interaction. The excitation spectrum is obtained within the linearized theory.
While superfluidity may take place at a definite ratio of the Fermi momentum,
rest mass and coupling constant, the metric coefficients play predominant role
forming the gap of excitation spectrum.

</DOC>
<DOC>
<DOCNO> 85230 </DOCNO>
Mother templates for gravitational wave chirps


  Templates used in a search for binary black holes and neutron stars in
gravitational wave interferometer data will have to be computed on-line since
the computational storage and retrieval costs for the template bank are too
expensive. The conventional dimensionless variable $T=(c^3/Gm)t,$ where $m$ is
the total mass of a binary, in the time-domain and a not-so-conventional
velocity-like variable $v=(\pi Gm f)^{1/3}$ in the Fourier-domain, render the
phasing of the waves independent of the total mass of the system enabling the
construction of {\it mother templates} that depend only on the mass ratio of a
black hole binary. Use of such mother templates in a template bank will bring
about a reduction in computational costs up to a factor of 10 and a saving on
storage by a factor of 100.

</DOC>
<DOC>
<DOCNO> 80696 </DOCNO>
What are the Confining Field Configurations of Strong-Coupling Lattice


  Starting from the strong-coupling SU(2) Wilson action in D=3 dimensions, we
derive an effective, semi-local action on a lattice of spacing L times the
spacing of the original lattice. It is shown that beyond the adjoint
color-screening distance, i.e. for $L \ge 5$, thin center vortices are stable
saddlepoints of the corresponding effective action. Since the entropy of these
stable objects exceeds their energy, center vortices percolate throughout the
lattice, and confine color charge in half-integer representations of the SU(2)
gauge group. This result contradicts the folklore that confinement in
strong-coupling lattice gauge theory, for D>2 dimensions, is simply due to
plaquette disorder, as is the case in D=2 dimensions. It also demonstrates
explicitly how the emergence and stability of center vortices is related to the
existence of color screening by gluon fields.

</DOC>
<DOC>
<DOCNO> 178461 </DOCNO>
Hyperon polarization in kaon photoproduction from the deuteron


  We analyze the reaction gamma + d --> K^+ + Lambda (Sigma) + N using the
Nijmegen soft core hyperon-nucleon interactions NSC97f and NSC89 and a recently
updated production operator for the gamma + N --> K^+ + Lambda(Sigma)
processes. Significant effects of the YN final state interaction are found near
both the K^+ Lambda N and K^+ Sigma N thresholds.

</DOC>
<DOC>
<DOCNO> 119801 </DOCNO>
Digital Sky Surveys: Software Tools and Technologies


  Large digital sky surveys, over a broad range of wavelengths, both from the
ground and from space observatories, are becoming a major source of
astronomical data. Some examples include the Sloan Digital Sky Survey (SDSS)
and the Digital Palomar Observatory Sky Survey (DPOSS) in the visible, the
Two-Micron All-Sky Survey (2MASS) in the near-infrared, the NRAO VLA Sky Survey
(NVSS) and the Faint Images of the Radio Sky at Twenty centimeters (FIRST) in
the radio. Many others surveys are planned or expected, in addition to the
previously named surveys. While most surveys are exclusively imaging,
large-scale spectroscopic surveys also exist. In addition, a number of
experiments with specific scientific goals, e.g., microlensing surveys for
MACHOs, searches for near-Earth asteroids, are generating comparable data
volumes. Typical sizes of resulting data sets (as of the late 1990's) are in
the range of tens of Terabytes of digital information, with detections of many
millions or even billions of sources, and several tens of parameters measured
for each detected source. This vast amount of new information presents both a
great scientific opportunity and a great technological challenge: how to
process, and calibrate the raw data; how to store, combine, and access them
using modern computing hardware and networks; and how to visualize, explore and
analyses these great data sets quickly and efficiently.

</DOC>
<DOC>
<DOCNO> 150691 </DOCNO>
Vector supersymmetry of Chern-Simons theory at finite temperature


  The existence of the vector supersymmetry is analysed within the context of
the finite temperature Chern-Simons theory.

</DOC>
<DOC>
<DOCNO> 10186 </DOCNO>
Slow holes in the triangular Ising antiferromagnet


  We consider the problem of the doped Ising antiferromagnet on the frustrated
triangular lattice in the limit where the hole kinetic energy is much smaller
than the Ising exchange. For a {\it single} hole we prove a ``frustrated
Nagaoka theorem'' showing that the ground state is magnetized and breaks
translational symmetry, in contrast to the parent insulating state that is
unmagnetized and spatially homogenous. The extension of this physics to finite
dopings depends on the strength of a density-density coupling that is
inevitably present - we find either phase separation of the holes, or a
superconducting state that is {\it also} magnetized and breaks translational
symmetry in a feat of spatial self-organization. Finally, we derive an
effective interaction between dilute holes at temperatures in excess of the
hopping and find an oscillatory, long-ranged form reflective of the
correlations in the underlying classical magnet which presages the breaking of
translational symmetry at zero temperature.

</DOC>
<DOC>
<DOCNO> 122869 </DOCNO>
Cosmic Microwave Background Polarization Signals from Tangled Magnetic


  Tangled, primordial cosmic magnetic fields create small rotational velocity
perturbations on the last scattering surface (LSS) of the cosmic microwave
background radiation (CMBR). For fields which redshift to a present value of
$B_0 = 3\times 10^{-9}$ Gauss, these vector modes are shown to generate
polarization anisotropies of order $0.1\mu K - 4 \mu K$ on small angular scales
($ 500 < l < 2000$), assuming delta function or a power law spectra with
$n=-1$. About 200 times larger signals result for $n=2$ spectra. Unlike
inflation generated, scalar modes, these signals are dominated by the odd
parity, B-type polarization, which could help in their detection.

</DOC>
<DOC>
<DOCNO> 10216 </DOCNO>
Hierarchy of Critical Exponents on Sierpinski fractal resistor networks


  Using the S_3-symmetry of Sierpinski fractal resistor networks we determine
the current distribution as well as the multifractals spectrum of moments of
current distribution by using the real space renormalization group technique
based on ([q/4]+1) independent Schure's invariant polynomials of inwards
flowing currents.

</DOC>
<DOC>
<DOCNO> 68003 </DOCNO>
Limits on excited tau leptons masses from leptonic tau decays


  We study the effects induced by excited leptons on the leptonic tau decay at
one loop level. Using a general effective lagrangian approach to describe the
couplings of the excited leptons, we compute their contributions to the
leptonic decays and use the current experimental values of the branching ratios
to put limits on the mass of excited states and the substructure scale.

</DOC>
<DOC>
<DOCNO> 72099 </DOCNO>
TESLA: Potentials of $\gamma\gamma$ and $e^+e^-$ Options in Stoponium


  In some supersymmetric extensions of the Standard Model fairly light
superpartner of t-quark is predicted, which may form bound states - stoponiums.
We estimate potentials of TESLA linear collider in search for stoponium,
considering the basic e+e- option and the gamma-gamma option (Photon Linear
Collider - PLC).
  It is found that PLC could be the best machine for discovery of these new
narrow strong resonances. It can produce thousands stoponiums per 100 fb$^-1$
integrated luminosity in the high energy peak. In the case of scenarios when
stoponium decays mainly into gluons the signal/background ratio is about 1/4.
The channel S->hh into two lightest Higgs bosons could be also seen with high
significance. Thus, several weeks run is sufficient for the stoponium
discovery, if its mass is approximately known (e.g. from observation of direct
stops production at LHC). Then, in MSSM scenarios with dominant S->hh decay PLC
shows excellent possibilities to discover bound state of stops, practically
immediately after beginning of operating.
  The e+e- option also has some prospects to observe stoponium but only in the
case of scenarios with dominant decay into two lightest Higgs bosons, with tens
of events per 100 $fb^{-1}$. Interesting possibility appears in the case when
the resonance is seated on 0.1% width luminosity peak - one could resolve the
stoponium exited states.

</DOC>
<DOC>
<DOCNO> 80931 </DOCNO>
QCDOC: A 10-teraflops scale computer for lattice QCD


  The architecture of a new class of computers, optimized for lattice QCD
calculations, is described. An individual node is based on a single integrated
circuit containing a PowerPC 32-bit integer processor with a 1 Gflops 64-bit
IEEE floating point unit, 4 Mbyte of memory, 8 Gbit/sec nearest-neighbor
communications and additional control and diagnostic circuitry. The machine's
name, QCDOC, derives from ``QCD On a Chip''.

</DOC>
<DOC>
<DOCNO> 7765 </DOCNO>
Adhesion-Induced Lateral Phase Separation in Membranes


  Adhesion between membranes is studied using a phenomenological model, where
the inter-membrane distance is coupled to the concentration of sticker
molecules on the membranes. The model applies to both for adhesion of two
flexible membranes and to adhesion of one flexible membrane onto a second
membrane supported on a solid substrate. We mainly consider the case where the
sticker molecules form bridges and adhere directly to both membranes. The
calculated mean-field phase diagrams show an upward shift of the transition
temperature indicating that the lateral phase separation in the membrane is
enhanced due to the coupling effect. Hence the possibility of adhesion-induced
lateral phase separation is predicted. For a particular choice of the
parameters, the model exhibits a tricritical behavior. We also discuss the
non-monotonous shape of the inter-membrane distance occurring when the lateral
phase separation takes place. The inter-membrane distance relaxes to the bulk
values with two symmetric overshoots. Adhesion mediated by other types of
stickers is also considered.

</DOC>
<DOC>
<DOCNO> 68056 </DOCNO>
Signature for heavy Majorana neutrinos in hadronic collisions


  The production and decay of new possible heavy Majorana neutrinos are
analyzed in hadronic collisions. New bounds on the mixing of these particles
with standard neutrinos are estimated according to a fundamental representation
suggested by grand unified models.
  A clear signature for these Majorana neutrinos is given by same-sign
dileptons plus a charged weak vector boson in the final state. We discuss the
experimental possibilities for the future Large Hadron Collider (LHC) at CERN.

</DOC>
<DOC>
<DOCNO> 8502 </DOCNO>
Evidence for coexistence of the superconducting gap and the pseudo - gap


  We present intrinsic tunneling spectroscopy measurements on small
Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ mesas. The tunnel conductance curves show both
sharp peaks at the superconducting gap voltage and broad humps representing the
$c$-axis pseudo-gap. The superconducting gap vanishes at $T_c$, while the
pseudo-gap exists both above and below $T_c$. Our observation implies that the
superconducting and pseudo-gaps represent different coexisting phenomena.

</DOC>
<DOC>
<DOCNO> 10479 </DOCNO>
Polariton Local States in Periodic Bragg Multiple Quantum Well


  We analytically study optical properties of several types of defects in Bragg
multiple quantum well structures. We show that a single defect leads to two
local polariton modes in the photonic band gap. These modes lead to
peculiarities in reflection and transmission spectra. Detailed recommendations
for experimental observation of the studied effects are given.

</DOC>
<DOC>
<DOCNO> 174499 </DOCNO>
Strongly Enhanced Low Energy Alpha-Particle Decay in Heavy Actinide


  Relatively low energy and very enhanced alpha-particle groups have been
observed in various actinide fractions produced via secondary reactions in a
CERN W target which had been irradiated with 24-GeV protons. In particular,
5.14, 5.27 and 5.53 MeV alpha-particle groups with corresponding half-lives of
3.8(+ -)1.0 y, 625(+ -)84 d and 26(+ -)7 d, have been seen in Bk, Es and Lr-No
sources, respectively. The measured energies are a few MeV lower than the known
g.s. to g.s. alpha-decays in the corresponding neutron-deficient actinide
nuclei. The half-lives are 4 to 7 orders of magnitude shorter than expected
from the systematics of alpha-particle decay in this region of nuclei. The
deduced evaporation residue cross sections are in the mb region, about 4 orders
of magnitude higher than expected. A consistent interpretation of the data is
given in terms of production of long-lived isomeric states in the second and
third wells of the potential-energy surfaces of the parent nuclei, which decay
to the corresponding wells in the daughters. The possibility that the isomeric
states in the third minimum are actually the true or very near the true ground
states of the nuclei, and consequences regarding the production of the
long-lived superheavy elements, are discussed.

</DOC>
<DOC>
<DOCNO> 71880 </DOCNO>
Analytical description of quasivacuum oscillations of solar neutrinos


  We propose a simple prescription to calculate the solar neutrino survival
probability P_{ee} in the quasivacuum oscillation (QVO) regime. Such
prescription is obtained by matching perturbative and exact analytical results,
which effectively take into account the density distribution in the Sun as
provided by the standard solar model. The resulting analytical recipe for the
calculation of P_{ee} is shown to reach its highest accuracy |\Delta P_{ee}| <
2.6 x 10^{-2} in the whole QVO range) when the familiar prescription of
choosing the solar density scale parameter r_0 at the
Mikheyev-Smirnov-Wolfenstein (MSW) resonance point is replaced by a new one,
namely, when r_0 is chosen at the point of ``maximal violation of
adiabaticity'' (MVA) along the neutrino trajectory in the Sun. The MVA
prescription admits a smooth transition from the QVO regime to the MSW
transition one. We discuss in detail the phase acquired by neutrinos in the
Sun, and show that it might be of relevance for the studies of relatively short
timescale variations of the fluxes of the solar \nu lines in the future
real-time solar neutrino experiments. Finally, we elucidate the role of matter
effects in the convective zone of the Sun.

</DOC>
<DOC>
<DOCNO> 80950 </DOCNO>
Zero-momentum modes and chiral limit in compact lattice QED


  The influence of zero-momentum gauge modes on physical observables is
investigated for compact lattice QED with dynamical and quenched Wilson
fermions. Within the Coulomb phase, zero-momentum modes are shown to hide the
critical behaviour of gauge invariant fermion observables near the chiral
limit. Methods for eliminating zero-momentum modes are discussed.

</DOC>
<DOC>
<DOCNO> 117210 </DOCNO>
Comment on ``Dependence of Gravitational Action on Chemical Composition:


  In our comment we show that the application of appropriate statistical
methods to the results of the author proves that the author in his article has
not been able to reach his goal.

</DOC>
<DOC>
<DOCNO> 84367 </DOCNO>
Angular momentum and an invariant quasilocal energy in general


  Owing to its transformation property under local boosts, the Brown-York
quasilocal energy surface density is the analogue of E in the special
relativity formula: E^2-p^2=m^2. In this paper I will motivate the general
relativistic version of this formula, and thereby arrive at a geometrically
natural definition of an `invariant quasilocal energy', or IQE. In analogy with
the invariant mass m, the IQE is invariant under local boosts of the set of
observers on a given two-surface S in spacetime. A reference energy subtraction
procedure is required, but in contrast to the Brown-York procedure, S is
isometrically embedded into a four-dimensional reference spacetime. This
virtually eliminates the embeddability problem inherent in the use of a
three-dimensional reference space, but introduces a new one: such embeddings
are not unique, leading to an ambiguity in the reference IQE. However, in this
codimension-two setting there are two curvatures associated with S: the
curvatures of its tangent and normal bundles. Taking advantage of this fact, I
will suggest a possible way to resolve the embedding ambiguity, which at the
same time will be seen to incorporate angular momentum into the energy at the
quasilocal level. I will analyze the IQE in the following cases: both the
spatial and future null infinity limits of a large sphere in asymptotically
flat spacetimes; a small sphere shrinking toward a point along either spatial
or null directions; and finally, in asymptotically anti-de Sitter spacetimes.
The last case reveals a striking similarity between the reference IQE and a
certain counterterm energy recently proposed in the context of the conjectured
AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 70958 </DOCNO>
The $\pi^2$ terms in the s-channel QCD observables


  We analyze the effect of $\pi^2$-terms in the QCD perturbative expansions for
the s-channel effective coupling and observables, the effect known from the
80s. We remind that these terms can be collected into specific functions --
strong s-channel coupling $\tilda{\alpha}_s$ and its effective powers
${\mathfrak A}(s)$ free of ghost singularities. Further on, we study the
structure of perturbation theory for observables and its reformulation in terms
of nonpower perturbation expansion over the set $\{\mathfrak A}(s)\}.$\par
values of $\alpha_s$ as extracted from experiments. The main result is that the
common two-loop (NLO, NLLA) approximation widely used in the five-quark ($10
\GeV\lesssim \sqrt{s}\lesssim 170 \GeV$) region for a shape analysis contains a
systematic negative error of a 1-2 per cent order of magnitude for the
extracted $\bar{\alpha}_s^{(2)}$. Our physical conclusion is that the
$\alpha_s(M_Z)$ value averaged over the f=5 data $<\alpha_s(M_Z)>_{f=5} \simeq
0.124$ appreciably differs from the currently accepted "world average"
(=0.118).}

</DOC>
<DOC>
<DOCNO> 99586 </DOCNO>
Solutions of D_\alpha - 0 from Homogeneous Invariant Functions


  We prove that the existence of a homogeneous invariant of degree n for a
representation of a semi-simple Lie group guarantees the existence of
non-trivial solutions of D_{\alpha} = 0: these correspond to the maximum value
of the square of the invariant divided by the norm of the representation to the
n^{th} power.

</DOC>
<DOC>
<DOCNO> 84880 </DOCNO>
Hamiltonian analysis of General relativity with the Immirzi parameter


  Starting from a Lagrangian we perform the full constraint analysis of the
Hamiltonian for General relativity in the tetrad-connection formulation for an
arbitrary value of the Immirzi parameter and solve the second class
constraints, presenting the theory with a Hamiltonian composed of first class
constraints which are the generators of the gauge symmetries of the action. In
the time gauge we then recover Barbero's formulation of gravity.

</DOC>
<DOC>
<DOCNO> 101045 </DOCNO>
From flows and metrics to dynamics


  Recall that a vector field on an n-dimensional differentiable manifold M is a
mapping X defined on M with values in the tangent bundle TM that assigns to
each point $x\in M$ a vector X(x) in the tangent space $T_x M$. A vector field
may be interpreted alternatively as the right-hand side of an autonomous system
of first-order ordinary differential equations, i.e., a flow. Now we show that
any flow can be enveloped by a conservative dynamics using a semi-Riemann
metric g on M. This kind of dynamics was called {\it geometric dynamics}
[7]-[9].
  The given vector field, the initial semi-Riemann metric, the Levi-Civita
connection, and an associated (1,1)-tensor field are used to build a new
geometric structure (e.g., semi-Riemann-Jacobi, semi-Riemann-Jacobi-Lagrange,
semi-Finsler-Jacobi, etc) on the manifold M ensuring that all the trajectories
of a geometric dynamics are pregeodesics (Lorentz-Udri\c{s}te world-force law).
Implicitly, we solved a problem rised first by Poincar\'e: find a suitable
geometric structure that converts the trajectories of a given vector field into
geodesics.

</DOC>
<DOC>
<DOCNO> 13613 </DOCNO>
Counterion correlations and attraction between like-charged


  A simple model is presented for the appearance of attraction between two like
charged polyions inside a polyelectrolyte solution. The polyions are modeled as
rigid cylinders in a continuum dielectric solvent. The strong electrostatic
interactions between the polyions and the counterions results in counterion
condensation. If the two polyions are sufficiently close to each other their
layers of condensed counterions can become correlated resulting in attraction
between the macromolecules. To explore the counterion induced attraction we
calculate the correlation functions for the condensed counterions. It is found
that the correlations are of very short range. For the parameters specific to
the double stranded DNA, the correlations and the attraction appear only when
the surface-to-surface separation is less than 7 /AA.

</DOC>
<DOC>
<DOCNO> 11852 </DOCNO>
Some Low-Temperature Properties of a Generalized Hubbard Model with


  In the present paper we study some correlation effects in a generalized
Hubbard model with correlated hopping within low-temperature region using a
generalized mean-field approximation. It is shown that in a series of cases the
model leads to consequences deviating essentially from those of the Hubbard
model. We consider the possibility of applying the result to interpret the
peculiarities of physical properties of systems with narrow energy bands.

</DOC>
<DOC>
<DOCNO> 68238 </DOCNO>
Charmed hadrons production in high-energy $\Sigma^-$ beam


  We present the calculation of the inclusive x_F-distributions of charmed
hadrons, produced in high-energy $\Sigma^-$-beam. Our calculation is based on
the modified mechanism of charmed quarks fragmentation as well as on the
mechanism of c-quark recombination with the valence quarks from initial
hadrons.

</DOC>
<DOC>
<DOCNO> 69360 </DOCNO>
Can instantons saturate the large mass of the $\eta'$ meson in the


  Using the trace anomaly and low energy relations, as well as Witten-Veneziano
formula for the mass of the $\eta'$ meson, the chiral topology of the QCD
nonperturbative instanton vacuum has been numerically evaluated. Our formalism
makes it possible to express the topological susceptibility and the mass of the
$\eta'$ meson as a functions of the instanton number density in the chiral
limit. We have explicitly shown that the topological susceptibility in this
case is approximately one fours and one half of its phenomenological value at
instanton number densities in the chiral limit, 0.5 fm^{-4} and 1.0 fm^{-4},
respectively. Thus the instanton contributions substantially underestimate the
mass of the $\eta'$ meson which still remains large in the chiral limit. With
the help of the above-mentioned Witten-Veneziano formula, we derived an
absolute lower bounds for the pion decay constant and the mass of the $\eta'$
meson in the chiral limit.

</DOC>
<DOC>
<DOCNO> 40380 </DOCNO>
Observation of New States Decaying into $\Lambda_{c}^{+}\pi^{-}\pi^{+}$


  Using 13.7 fb^{-1} of data recorded by the CLEO detector at CESR, we
investigate the spectrum of charmed baryons which decay into Lambda_c^+ pi^-
pi^+ and are more massive than the Lambda_{c1} baryons. We find evidence for
two new states: one is broad and has an invariant mass roughly 480 MeV above
that of the Lambda_c^+; the other is narrow with an invariant mass of 596 +- 1
+- 2 MeV above the Lambda_c^+ mass. These results are preliminary.

</DOC>
<DOC>
<DOCNO> 68551 </DOCNO>
Minimal surfaces and Reggeization in the AdS/CFT correspondence


  We address the problem of computing scattering amplitudes related to the
correlation function of two Wilson lines and/or loops elongated along
light-cone directions in strongly coupled gauge theories. Using the AdS/CFT
correspondence in the classical approximation, the amplitudes are shown to be
related to minimal surfaces generalizing the {\em helicoid} in various $AdS_5$
backgrounds. Infra-red divergences appearing for Wilson lines can be factorized
out or can be cured by considering the IR finite case of correlation functions
of two Wilson loops. In non-conformal cases related to confining theories,
reggeized amplitudes with linear trajectories and unit intercept are obtained
and shown to come from the approximately flat metrics near the horizon, which
sets the scale for the Regge slope. In the conformal case the absence of
confinement leads to a different solution. A transition between both regimes
appears, in a confining theory, when varying impact parameter.

</DOC>
<DOC>
<DOCNO> 8756 </DOCNO>
Anomalies in the ab-plane resistivity of strongly underdoped


  We present and discuss the results of measurements of the ab-plane
resistivity of La_{2-x}Sr_{x}CuO_{4} single crystals with small Sr contents
(x=0.052-0.075). The resistivity was obtained in the temperature range between
4.2 K and 300 K by using an AC Van der Pauw technique. When the temperature is
lowered, the rho_{ab}(T) curves show a transition from a linear behaviour to a
semiconducting-like one. The deviation from the linearity occurs at a
doping-dependent temperature T_{ch}. This effect can be interpreted as due to a
progressive pinning of preexistent charge stripes. In the same framework, the
appearance of anomalous sharp peaks in the rho_{ab}(T) curves of
superconducting samples just above T_{c} may be explained by a transition from
a nematic to a more ordered smectic electronic stripe phase.

</DOC>
<DOC>
<DOCNO> 152126 </DOCNO>
Noncommutative Supersymmetric Gauge Anomaly


  We extend the general method of hep-th/0009192 to compute the consistent
gauge anomaly for noncommutative 4d SSYM coupled to chiral matter. The choice
of the minimal homotopy path allows us to obtain a simple and compact result.
We perform the reduction to components in the WZ gauge proving that our result
contains, as lowest component, the bosonic chiral anomaly for noncommutative YM
theories recently obtained in literature.

</DOC>
<DOC>
<DOCNO> 119457 </DOCNO>
FUSE Observations of Molecular Hydrogen in Translucent Interstellar


  We report the results of initial FUSE observations of molecular hydrogen (H2)
in translucent clouds. These clouds have greater optical depth than any of the
diffuse clouds previously observed for far-UV H2 absorption, and provide new
insights into the physics and chemistry of such regions. Our initial results
involve observations of HD 73882, a well-studied southern hemisphere star lying
behind substantial interstellar material (E(B-V) = 0.72; A_V = 2.44). We find a
total H2 column density, N(H2) = 1.2 x 10^{21} cm^{-2}, about three times
larger than the values for diffuse clouds previously measured in the far-UV.
The gas kinetic temperature indicated by the ratio N(J=1)/N(J=0) is 58 +/- 10
K. With the aid of ground-based data to calculate an appropriate
multi-component curve of growth, we have determined column densities for all
rotational levels up to J = 7. The J >= 2 states can be reasonably fitted with
a rotational excitation temperature of 307 +/- 23 K. Both the kinetic and
rotational temperatures are similar to those found in previous investigations
of diffuse clouds. The ratios of carbonaceous molecules to hydrogen molecules
are also similar to ratios in diffuse clouds, suggesting a similar chemistry
for this line of sight.

</DOC>
<DOC>
<DOCNO> 13221 </DOCNO>
Exactly solvable model of dissipative vortex tunneling


  I consider the problem of vortex tunneling in a two-dimensional
superconductor. The vortex dynamics is governed by the Magnus force and the
Ohmic friction force. Under-barrier motion in the vicinity of the saddle point
of the pinning potential leads to a model with quadratic Hamiltonian which can
be analytically diagonalized. I find the dependence of the tunneling
probability on the normal state quasiparticle relaxation time $\tau$ with a
minimum at $\omega_0\tau\sim 1$, where $\omega_0$ is the level spacing of the
quasiparticle bound states inside the vortex core. The results agree
qualitatively with the available experimental data.

</DOC>
<DOC>
<DOCNO> 123092 </DOCNO>
XMM-Newton observation of the Tycho Supernova Remnant


  We present the observation of the Tycho supernova remnant obtained with the
EPIC and RGS instruments onboard the XMM-Newton satellite. We compare images
and azimuthally averaged radial profiles in emission lines from different
elements (silicon and iron) and different transition lines of iron (Fe L and Fe
K). While the Fe XVII L line and Si XIII K line images are globally spatially
coincident, the Fe K emission clearly peaks at a smaller radius, indicating a
higher temperature toward the reverse shock. This is qualitatively the profile
expected when the reverse shock, after travelling through the outer power-law
density profile, has entered the central plateau of the ejecta. The high energy
continuum map has an overall smooth distribution, with a similar extent to the
radio emission. Its radial profile peaks further out than the lines emission.
Brighter and harder continuum regions are observed with a rough bipolar
symmetry in the eastern and western edges. The spectral analysis of the
southeastern knots supports spatial variations of the relative abundance of
silicon and iron, which implies an incomplete mixing of the silicon and iron
layers.

</DOC>
<DOC>
<DOCNO> 117907 </DOCNO>
The Toronto Red-Sequence Cluster Survey: First Results


  The Toronto Red-Sequence Cluster Survey (TRCS) is a new galaxy cluster survey
designed to provide a large sample of optically selected 0.1 < z < 1.4
clusters. The planned survey data is 100 square degrees of two color (R and z')
imaging, with a 5-sigma depth ~2 mag past M* at z=1. The primary scientific
drivers of the survey are a derivation of Omega_m and sigma_8 (from N(M,z) for
clusters) and a study of cluster galaxy evolution with a complete sample. This
paper gives a brief outline of the TRCS survey parameters and sketches the
methods by which we intend to pursue the main scientific goals, including an
explicit calculation of the expected survey completeness limits. Some
preliminary results from the first set of data (~6 deg^2) are also given. These
preliminary results provide new examples of rich z~1 clusters, strong cluster
lensing, and a possible filament at z~1.

</DOC>
<DOC>
<DOCNO> 85573 </DOCNO>
Differential Geometry from Differential Equations


  We first show how, from the general 3rd order ODE of the form
z'''=F(z,z',z'',s), one can construct a natural Lorentzian conformal metric on
the four-dimensional space (z,z',z'',s). When the function F(z,z',z'',s)
satisfies a special differential condition of the form, U[F]=0, the conformal
metric possesses a conformal Killing field, xi = partial with respect to s,
which in turn, allows the conformal metric to be mapped into a three
dimensional Lorentzian metric on the space (z,z',z'') or equivalently, on the
space of solutions of the original differential equation. This construction is
then generalized to the pair of differential equations, z_ss =
S(z,z_s,z_t,z_st,s,t) and z_tt = T(z,z_s,z_t,z_st,s,t), with z_s and z_t, the
derivatives of z with respect to s and t. In this case, from S and T, one can
again, in a natural manner, construct a Lorentzian conformal metric on the six
dimensional space (z,z_s,z_t,z_st,s,t). When the S and T satisfy equations
analogous to U[F]=0, namely equations of the form M[S,T]=0, the 6-space then
possesses a pair of conformal Killing fields, xi =partial with respect to s and
eta =partial with respect to t which allows, via the mapping to the four-space
of z, z_s, z_t, z_st and a choice of conformal factor, the construction of a
four-dimensional Lorentzian metric. In fact all four-dimensional Lorentzian
metrics can be constructed in this manner. This construction, with further
conditions on S and T, thus includes all (local) solutions of the Einstein
equations.

</DOC>
<DOC>
<DOCNO> 9056 </DOCNO>
New paradoxical games based on Brownian ratchets


  Based on Brownian ratchets, a counter-intuitive phenomenon has recently
emerged -- namely, that two losing games can yield, when combined, a
paradoxical tendency to win. A restriction of this phenomenon is that the rules
depend on the current capital of the player. Here we present new games where
all the rules depend only on the history of the game and not on the capital.
This new history-dependent structure significantly increases the parameter
space for which the effect operates.

</DOC>
<DOC>
<DOCNO> 120726 </DOCNO>
Water in Emission in the ISO Spectrum of the Early M Supergiant Star mu


  We report a detection of water in emission in the spectrum of the M2
supergiant atar mu Cep (M2Ia) observed by the Short Wavelength Spectrometer
(SWS) aboard Infrared Space Observatory (ISO) and now released as the ISO
Archives. The emission first appears in the 6 micron region (nu2 fundamental)
and then in the 40 micron region (pure rotation lines) despite the rather
strong dust emission. The intensity ratios of the emission features are far
from those of the optically thin gaseous emission. Instead, we could reproduce
the major observed emission features by an optically thick water sphere of the
inner radius about two stellar radii (1300Rsun), Tex = 1500K, and Ncol (H2O) =
3.0E+20/cm2. This model also accounts for the H2O absorption bands in the near
infrared (1.4, 1.9, and 2.7 micron) as well. The detection of water in emission
provides strong constraints on the nature of water in the early M supergiant
stars, and especially its origin in the outer atmosphere is confirmed against
other models such as the large convective cell model. We finally confirm that
the early M supergiant star is surrounded by a huge optically thick sphere of
the warm water vapor, which may be referred to as MOLsphere for simplicity.
Thus, the outer atmosphere of M supergiant stars should have a complicated
hierarchical and/or hybrid structure with at least three major constituents
including the warm MOLsphere (T about 1.0E+3K) together with the previously
known hot chromosphere (T about 1.0E+4K) and cool expanding gas-dust envelope
(T about 1.0E+2K).

</DOC>
<DOC>
<DOCNO> 101779 </DOCNO>
Basic Dynamical Systems Control of Aeroengine Flow


  The notions of basic controllability and basic control are defined using
dynamical systems theory of partial differential equations. A quadratic optimal
control of the linearized viscous Moore-Greitzer equation is presented and it
is confirmed that stall is uncontrollable in this model. A basic control is
constructed for the nonlinear viscous Moore-Greitzer equation which can control
both surge and stall. Numerical simulations of the basic control are presented.

</DOC>
<DOC>
<DOCNO> 70205 </DOCNO>
Strange quarks, magnetic moments and SU(3)


  We discuss the agreement in sign between the recently measured strange
contribution to the proton magnetic moment and SU(3) based fits to baryon octet
magnetic moments.

</DOC>
<DOC>
<DOCNO> 169965 </DOCNO>
Symmetric Hybrid Dynamics: A canonical formulation of coupled


  A canonical formulation of coupled classical-quantum dynamics is presented.
The theory is named symmetric hybrid dynamics. It is proved that under some
general conditions its predictions are consistent with the full quantum ones.
Moreover symmetric hybrid dynamics displays a fully consistent canonical
structure. Namely, it is formulated over a Lie algebra of observables, time
evolution is unitary and the solution of a hybrid type Schr\"odinger equation.
A quantization prescription from classical mechanics to hybrid dynamics is
presented. The quantization map is a Lie algebra isomorphism. Finally some
possible applications of the theory are succinctly suggested.

</DOC>
<DOC>
<DOCNO> 71903 </DOCNO>
Three-loop non-diagonal current correlators in QCD and NLO corrections


  The non-diagonal correlators of vector and scalar currents are considered at
three-loop order in QCD. The full mass dependence is computed in the case where
one of the quarks is massless and the other one carries the mass $M$. As
applications we consider the single-top-quark production via the process
$q\bar{q}\to t\bar{b}$ and the decay rate of a charged Higgs into hadrons. In
both cases the computed NLO corrections are shown to be numerically much less
important than the leading ones.

</DOC>
<DOC>
<DOCNO> 117591 </DOCNO>
The optical-ultraviolet continuum of Seyfert 2 galaxies


  This paper aims to understand the continuum of Seyfert 2 galaxies. By fitting
the single galaxies in the sample of Heckman et al. (1995) with composite
models (shock+ photoionization from the active center), we show that five main
components characterize the SED of the continuum. Shocks play an important role
since they produce a high temperature zone where soft X-rays are emitted.
  We show that in the optical-UV range, the slope of the NLR emission
reproduces the observed values, and may be the main component of the
featureless continuum. The presence of star forming regions cannot be excluded
in the circumnuclear region of various Seyfert galaxies. An attempt is made to
find their fingerprints in the observed AGN spectra. Finally, it is
demonstrated that multi-cloud models are necessary to interpret the spectra of
single objects, even in the global investigation of a sample of galaxies.

</DOC>
<DOC>
<DOCNO> 7812 </DOCNO>
Anisotropy of the Energy Gap in the Insulating Phase of the U-t-t'


  We apply a diagrammatic expansion method around the atomic limit (U >> t) for
the U-t-t' Hubbard model at half filling and finite temperature by means of a
continued fraction representation of the one-particle Green's function. From
the analysis of the spectral function A(\vec{k},\omega) we find an energy
dispersion relation with a (cos k_x-cos k_y)^2 modulation of the energy gap in
the insulating phase. This anisotropy is compared with experimental ARPES
results on insulating cuprates.

</DOC>
<DOC>
<DOCNO> 70838 </DOCNO>
Quantum anharmonic oscillator and quasi-exactly solvable Bose systems


  We extend the notion of quasi-exactly solvable (QES) models from potential
ones and differential equations to Bose systems. We obtain conditions under
which algebraization of the part of the spectrum occurs. In some particular
cases simple exact expressions for several energy levels of an anharmonic Bose
oscillator are obtained explicitly. The corresponding results do not exploit
perturbation theory and include strong coupling regime. A generic Hamiltonian
under discussion cannot, in contrast to QES potential models, be expressed as a
polynomial in generators of $sl_{2}$ algebra. The suggested approach is
extendable to many-particle Bose systems with interaction.

</DOC>
<DOC>
<DOCNO> 119618 </DOCNO>
Identifying Old Tidal Dwarf Irregulars


  We examine the observational consequences of the two possible origins for
irregular galaxies: formation from collapse of a primordial cloud of gas early
in the age of the Universe, and formation from tidal tails in an interaction
that could have occured any time in the history of the Universe. Because the
formation from tidal tails could have occurred a long time ago, proximity to
larger galaxies is not sufficient to distinguish tidal dwarfs from traditional
dwarfs. We consider the effects of little or no dark matter on rotation speeds
and the Tully-Fisher relationship, the metallicity-luminosity relationship,
structure, and stellar populations. From these selection criteria, we identify
a small list of dwarf irregular galaxies that are candidates for having formed
as tidal dwarfs.

</DOC>
<DOC>
<DOCNO> 119854 </DOCNO>
The Effect of Expansion on Mass Entrainment and Stability of


  We extend investigations of mass entrainment by jets, which previously have
focused on cylindrical supermagnetosonic jets and expanding trans-Alfv\'enic
jets, to a set of expanding supermagnetosonic jets. We precess these jets at
the origin to excite the helical mode of the Kelvin-Helmholtz (or KH)
instability, in order to compare the results with predictions from linear
stability analysis. We analyze this simulation set for the spatial development
of magnetized mass, which we interpret as jet plus entrained, initially
unmagnetized external mass. As with the previous simulation sets, we find that
the growth of magnetized mass is associated with the growth of the KH
instability through linear, nonlinear, and saturated stages and with the
expansion of magnetized material in simulated observations of the jet. From
comparison of measured wavelengths and wave speeds with the predictions from
linear stability analysis, we see evidence that the KH instability is the
primary cause for mass entrainment in these simulations, and that the expansion
reduces the rate of mass entrainment. This reduced rate can be observed as a
somewhat greater distance between the two transition points separating the
three stages of expansion.

</DOC>
<DOC>
<DOCNO> 9833 </DOCNO>
Low Temperature Thermal Transport in High Temperature Superconducting


  In order to separate electronic and phonon mechanisms of thermal transport in
high temperature superconducting Bi2212, we measured thermal conductivity of
single crystals of Y-doped Bi2212, an insulating analogue of pure Bi2212, in
the temperature range between 40 mK and 2 K. Temperature dependence of the
thermal conductivity of insulating samples changes from T$^{1.7}$ between 1 and
2 K to $T^{2.6}$ below 200 mK, indicating saturation of the phonon mean free
path with decreasing temperature. Overall, thermal conductivity of the
insulating samples (which is due entirely to phonons) is strongly suppressed in
comparison to that of the superconducting samples. Therefore, a large (and at
the lowest temperatures, predominant) part of the total thermal transport in
superconducting Bi2212 is due to electrons.

</DOC>
<DOC>
<DOCNO> 71698 </DOCNO>
New Exact Heavy Quark Sum Rules


  Considering nonforward scattering amplitude off the heavy quark in the Small
Velocity limit two exact superconvergent sum rules are derived. The first sum
rule leads to the lower bound \rho^2 > 3/4 for the slope of the Isgur-Wise
function. It also provides the rationale for the fact that the vector heavy
flavor mesons are heavier than the pseudoscalar ones. A spin-nonsinglet
analogue \bar\Sigma of \bar\Lambda = M_B-m_b is introduced.

</DOC>
<DOC>
<DOCNO> 120998 </DOCNO>
A new look at globular cluster colors in NGC 3311 and the case for


  NGC 3311, the central cD galaxy in the Hydra cluster, was previously thought
to host the most metal-rich globular cluster system known. Ground-based
Washington photometry had indicated the almost complete absence of the
population of globular clusters near [Fe/H] ~ -1 dex, normally dominant in the
metallicity distribution functions of giant elliptical galaxies. Lacking the
normal metal-poor globular cluster population, NGC 3311 was an outstanding
exception among galaxies, not easily understood under any of the current
globular cluster formation scenarios. Our HST/WFPC2 data yield normal globular
cluster colors and hence metallicities for this galaxy. We find a bi-modal
color distribution with peaks at (V-I)=0.91 +/- 0.03 and 1.09 +/- 0.03,
corresponding to [Fe/H] ~ -1.5 and -0.75 dex (somewhat dependent on the choice
of the conversion relation between color and metallicity). We review the
evidence for exclusively metal-rich globular cluster systems in other galaxies
and briefly discuss the implications for our understanding of globular cluster
and galaxy formation.

</DOC>
<DOC>
<DOCNO> 123008 </DOCNO>
Source-lens clustering effects on the skewness of the lensing


  The correlation between source galaxies and lensing potentials causes a
systematic effect on measurements of cosmic shear statistics, known as the
source-lens clustering (SLC) effect. The SLC effect on the skewness of lensing
convergence, $S_3$, is examined using a nonlinear semi-analytic approach and is
checked against numerical simulations. The semi-analytic calculations have been
performed in a wide variety of generic models for the redshift distribution of
source galaxies and power-law models for the bias parameter between the galaxy
and dark matter distributions. The semi-analytic predictions are tested
successfully against numerical simulations. We find the relative amplitude of
the SLC effect on $S_3$ to be of the order of five to forty per cent. It
depends significantly on the redshift distribution of sources and on the way
the bias parameter evolves. We discuss possible measurement strategies to
minimize the SLC effects.

</DOC>
<DOC>
<DOCNO> 120682 </DOCNO>
Triggered Star Formation in the Scorpius-Centaurus OB Association (Sco


  We explore the star formation history of the Upper Scorpius OB association,
the youngest part of Sco OB2. A wide field (160 square-degree) survey for
low-mass pre-main sequence (PMS) stars enabled us to increase the number of
known low-mass members of Upper Scorpius to nearly 100 stars. In a detailed
analysis of the locations of these stars in the HR diagram, taking proper
account of the uncertainties and the effects of unresolved binaries, we find a
mean stellar age of about 5 Myr and no evidence for a significant age
dispersion among these stars. This implies that the star formation history of
the Upper Scorpius association was dominated by a short star-burst, which
started about 5 Myr ago and ended probably not more than one or two Myr later.
Interestingly, the structure and kinematics of the HI shells surrounding the
Sco OB2 association show that the shock wave of a supernova explosion in the
nearby Upper Centaurus-Lupus association, the oldest part of Sco OB2, crossed
Upper Scorpius just about 5 Myr ago. This strongly suggests that this supernova
shock wave triggered the star-burst in Upper Scorpius.

</DOC>
<DOC>
<DOCNO> 72247 </DOCNO>
Standard Model Neutrinos as Warm Dark Matter


  Standard Model neutrinos are not usually considered plausible dark matter
candidates because the usual treatment of their decoupling in the early
universe implies that their mass must be sufficiently small to make them
``hot'' dark matter. In this paper we show that decoupling of Standard Model
neutrinos in low reheat models may result in neutrino densities very much less
than usually assumed, and thus their mass may be in the keV range. Standard
Model neutrinos may therefore be warm dark matter candidates.

</DOC>
<DOC>
<DOCNO> 100148 </DOCNO>
Generalized coherent states for SU(n) systems


  Generalized coherent states are developed for SU(n) systems for arbitrary
$n$. This is done by first iteratively determining explicit representations for
the SU(n) coherent states, and then determining parametric representations
useful for applications. For SU(n), the set of coherent states is isomorphic to
a coset space $SU(n)/SU(n-1)$, and thus shows the geometrical structure of the
coset space. These results provide a convenient $(2n - 1)$--dimensional space
for the description of arbitrary SU(n) systems. We further obtain the metric
and measure on the coset space, and show some properties of the SU(n) coherent
states.

</DOC>
<DOC>
<DOCNO> 67935 </DOCNO>
Calculation of Direct CP Violation in B Decays


  Using the generalized factorization approach, we calculate the CP asymmetries
of charmless B decays. A number of decay channels has large CP asymmetries,
which can be measured in the B factories.

</DOC>
<DOC>
<DOCNO> 100057 </DOCNO>
Theta Series of Unimodular Lattices, Combinatorial Identities and


  We find two combinatorial identities on the theta series of the root lattices
of the finite-dimensional simple Lie algebras of type $D_{4n}$ and the cosets
in their integral duals, in terms of the well-known Essenstein series $E_4(z)$
and Ramanujan series $\Dlt_{24}(z)$. Using these two identities, we determine
the theta series of certain infinite families of postive definite even
unimodular lattices obtained by gluing finite copies of the root lattices of
the finite-dimensional simple Lie algebras of type
 $D_{2n}$. It turns out that these theta series are weighted symmetric
polynomials of two fixed families of polynomials of $E_4(z)$ and
$\Dlt_{24}(z)$.

</DOC>
<DOC>
<DOCNO> 69799 </DOCNO>
Physical Results from Unphysical Simulations


  We calculate various properties of pseudoscalar mesons in partially quenched
QCD using chiral perturbation theory through next-to-leading order. Our results
can be used to extrapolate to QCD from partially quenched simulations, as long
as the latter use three light dynamical quarks. In other words, one can use
unphysical simulations to extract physical quantities - in this case the quark
masses, meson decay constants, and the Gasser-Leutwyler parameters L_4-L_8. Our
proposal for determining L_7 makes explicit use of an unphysical (yet
measurable) effect of partially quenched theories, namely the double-pole that
appears in certain two-point correlation functions. Most of our calculations
are done for sea quarks having up to three different masses, except for our
result for L_7, which is derived for degenerate sea quarks.

</DOC>
<DOC>
<DOCNO> 84794 </DOCNO>
Localization of gravitational field energy and a procedure proposed for


  Introduction of Vaidya metrics into the Expansive Nondecelerative Universe
model allows to localize the energy of gravitational field. On the assumption
that there is an interaction of long-range gravitational and electromagnetic
fields, the localization might be verified experimentally. In this contribution
some details on such an experiment are given.

</DOC>
<DOC>
<DOCNO> 8894 </DOCNO>
Reconstructions of diamond (100) and (111) surfaces: Accuracy of the


  We present a detailed comparison of the structural predictions of the
effective many-body Brenner potential with those of ab-initio studies for known
reconstructions of diamond (100) and (111) surfaces. These results suggest high
reliability of the Brenner potential for dealing with carbon-based structures
where different types of bonding are present at the same time.

</DOC>
<DOC>
<DOCNO> 13908 </DOCNO>
Formation of Chain-Folded Structures from Supercooled Polymer Melts


  The formation of chain-folded structures from the melt is observed in
molecular dynamics simulations resembling the lamellae of polymer crystals.
Crystallization and subsequent melting temperatures are related linearly to the
inverse lamellar thickness. Analysis of the single chain conformations in the
crystal shows that most chains reenter the same lamella by tight backfolds.
Simulations are performed with a mesoscopic bead-spring model including a
specific angle bending potential. They demonstrate that chain stiffness alone,
without an attractive inter-particle potential, is a sufficient driving force
for the formation of chain-folded lamellae.

</DOC>
<DOC>
<DOCNO> 8778 </DOCNO>
Superconducting correlations in ultra-small metallic grains


  To describe the crossover from the bulk BCS superconductivity to a
fluctuation-dominated regime in ultrasmall metallic grains, new order
parameters and correlation functions, such as ``parity gap'' and ``pair-mixing
correlation function'', have been recently introduced. In this paper, we
discuss the small-grain behaviour of the Penrose-Onsager-Yang off-diagonal
long-range order (ODLRO) parameter in a pseudo-spin representation. Relations
between the ODLRO parameter and those mentioned above are established through
analytical and numerical calculations.

</DOC>
<DOC>
<DOCNO> 100710 </DOCNO>
Classification of links up to self $#$-move


  A pass-move and a $#$-move are local moves on oriented links defined by L.H.
Kauffman and H. Murakami respectively. Two links are self pass-equivalent
(resp. self $#$-equivalent) if one can be deformed into the other by pass-moves
(resp. $#$-moves), where non of them can occur between distinct components of
the link. These relations are equivalence relations on ordered oriented links
and stronger than link-homotopy defined by J. Milnor. We give two complete
classifications of links with arbitrarily many components up to self
pass-equivalence and up to self $#$-equivalence respectively. So our
classifications give subdivisions of link-homotopy classes.

</DOC>
<DOC>
<DOCNO> 69336 </DOCNO>
TeV scale weak interactions: inclusive vs. exclusive observables


  Hard processes at the TeV scale exhibit enhanced (double log) EW corrections,
that need resummation in view of the high level of precision of Next Linear
Colliders. The fact that the weak sector is spontaneously broken causes some
peculiarities with respect to unbroken theories like QCD. For observables that
are exclusive with respect to $W,Z$ emission, some peculiar technical problems
have yet to be solved. Surprisingly, double logarithmic enhancements are
present even for inclusive observables like $e^+e^-\to$ hadrons, leading to
violation of the Bloch-Nordsieck theorem. The last effect is particularly
important, producing weak effects that in some cases compete in magnitude with
the strong ones.

</DOC>
<DOC>
<DOCNO> 119750 </DOCNO>
Reconstructing the History of Star Formation in Rich Cluster Cores


  We address the current crucial issues on the formation and evolution of
cluster galaxies: ie., connection between the Butcher-Oemler effect, assembly
of cluster galaxies, truncation of star formation, and the origin of S0
galaxies.
  We construct the field corrected colour-magnitude (CM) diagrams for 7 CNOC
clusters (0.23<z<0.43) and Coma, and illustrate the evolution of the complete
cluster population down to the present-day based on the model in which star
formation is truncated when the galaxies infall from the surrounding field.
  We show that the blue galaxies are incorporated into the present-day tight CM
relation as they fade and become redder after the truncation, which is possibly
responsible for producing faint S0's (>M*+1). Truncation of star formation is,
however, found to be relatively milder (with a time scale of 1 Gyr) than
suggested by the viorent processes such as ram-pressure stripping and/or
mergers/harassment.
  The BO effect is after all found to be a combination of three effects,
namely, increasing field star formation activity, increasing galaxy infall
rate, and the truncatin of star formation after the accretion. Our approach
naturally leads to the history of galaxy assembly and `global' star foramtion
for `cluster' galaxies.

</DOC>
<DOC>
<DOCNO> 121054 </DOCNO>
A Search for Point Sources of Cosmic Primary Rays Which Produce Single


  An increased data sample of identified secondary muons is collected at
detection level. Project GRAND identifies secondary cosmic ray muons from
electrons utilizing a thin steel absorber and tracking (PWC) chambers. The
resulting angular resolution for the primary is about +/- 5 degrees. Since
there is a 1.5% probability that a 100 GeV gamma primary will produce a single
muon track at ground level, the high statistics allows a search for angular
enhancements due to gammas. More than 100 billion muons are identified and
analyzed. A table of stellar sources is examined.

</DOC>
<DOC>
<DOCNO> 68509 </DOCNO>
Random matrix model for chiral symmetry breaking and color


  We consider a random matrix model which describes the competition between
chiral symmetry breaking and the formation of quark Cooper pairs in QCD at
finite density. We study the evolution of the phase structure in temperature
and chemical potential with variations of the strength of the interaction in
the quark-quark channel and demonstrate that the phase diagram can realize a
total of six different topologies. A vector interaction representing
single-gluon exchange reproduces a topology commonly encountered in previous
QCD models, in which a low-density chiral broken phase is separated from a
high-density diquark phase by a first-order line. The other five topologies
either do not possess a diquark phase or display a new phase and new critical
points. Since these five cases require large variations of the coupling
constants away from the values expected for a vector interaction, we conclude
that the phase diagram of finite density QCD has the topology suggested by
single-gluon exchange and that this topology is robust.

</DOC>
<DOC>
<DOCNO> 83090 </DOCNO>
Genetic Algorithms for Extension Search in Default Logic


  A default theory can be characterized by its sets of plausible conclusions,
called its extensions. But, due to the theoretical complexity of Default Logic
(Sigma_2p-complete), the problem of finding such an extension is very difficult
if one wants to deal with non trivial knowledge bases. Based on the principle
of natural selection, Genetic Algorithms have been quite successfully applied
to combinatorial problems and seem useful for problems with huge search spaces
and when no tractable algorithm is available. The purpose of this paper is to
show that techniques issued from Genetic Algorithms can be used in order to
build an efficient default reasoning system. After providing a formal
description of the components required for an extension search based on Genetic
Algorithms principles, we exhibit some experimental results.

</DOC>
<DOC>
<DOCNO> 10553 </DOCNO>
Surface extrapolation length and director structures in confined


  We report the results of Monte Carlo simulations of the Lebwohl--Lasher model
of nematic liquid crystals confined to cylindrical cavities with homeotropic
anchoring. We show that the ratio of the bulk to surface couplings is not in
general equal to the corresponding parameter K/W used in elastic theory (where
K is the Frank elastic constant in the one constant approximation and W is the
surface anchoring strength). By measuring the temperature dependence of K/W
(which is equivalent to the surface extrapolation length) we are able to
reconcile the results of our simulations as well as others with the predictions
of elastic theory. We find that the rate at which we cool the system from the
isotropic to nematic phase plays a crucial role in the development of the final
director structure, because of a large free energy barrier separating different
director structures as well as the temperature dependence of $K/W$. With a
suitably fast cooling rate we are able to keep the system out of a metastable
planar state and form an escaped radial structure for large enough systems.

</DOC>
<DOC>
<DOCNO> 69228 </DOCNO>
Testing CP Violation in the Higgs Sector at Muon Colliders


  We study the possibility of measuring the muon Yukawa couplings in s-channel
Higgs boson production at a muon collider with transversely polarized beams. We
investigate sensitivity to the relative size of the CP-odd and CP-even muon
Yukawa couplings. Provided the event rate observed justifies the operation of
the mu+mu- Higgs boson factory, we find that 40% polarization for both beams is
sufficient to resolve the CP nature of a single resonance as well as
disentangle it from two overlapping CP conserving resonances.

</DOC>
<DOC>
<DOCNO> 11152 </DOCNO>
Comment on "Models of Intermediate Spectral Statistics"


  In [1] it was proposed, that the nearest-neighbor distribution $P(s)$ of the
spectrum of the Bohr-Mottelson model is similar to the semi-Poisson
distribution. We show however, that $P(s)$ of this model differs considerably
in many aspects from semi-Poisson. In addition we give an asymptotic formula
for $P(s)$ as $s \to 0$, which gives $P'(0) = \pi\sqrt{3}/2$ for the slope at
$s=0$. This is different not only from the GOE case but also from the
semi-Poisson prediction that leads to $P'(0) = 4$

</DOC>
<DOC>
<DOCNO> 122083 </DOCNO>
Ram-Pressure Stripping on Dwarf Galaxies


  We use SPH/N-body simulations to study the ram-pressure stripping of the gas
of dwarf galaxies orbiting in a disc galaxy. The effects of the gaseous disc
and halo on the satellites are analysed and the results are compared with the
observations of the dwarf spheroidals (and dwarf irregulars) in the Local
Group. The stripped gas is compared with the High Velocity Clouds. Finally, a
model of evolution of the dwarfs is proposed.

</DOC>
<DOC>
<DOCNO> 178587 </DOCNO>
Mapping the proton drip line from Z=31 to Z=49


  The structure of proton drip line nuclei in the 60 < A < 100 mass range is
studied with the Relativistic Hartree Bogoliubov (RHB) model. For the elements
which determine the astrophysical rapid proton capture process path, the RHB
model predicts the location of the proton drip-line, the ground-state
quadrupole deformations and one-proton separation energies at and beyond the
drip-line. The results of the present theoretical investigation are compared
with available experimental data. For possible odd-Z ground state proton
emitters, the calculated deformed single-particle orbitals occupied by the odd
valence proton and the corresponding spectroscopic factors are compared with
predictions of the macroscopic-microscopic mass model.

</DOC>
<DOC>
<DOCNO> 151162 </DOCNO>
Evolving of a massless scalar field in Reissner-Nordstrom Anti-de Sitter


  We investigate the evolution of a scalar field propagating in
Reissner-Nordstr\"om Anti-de Sitter spacetime. Due to the characteristic of
spacetime geometry, the radiative tails associated with a massless scalar field
propagation have an oscillatory exponential decay. The object-picture of the
quasinormal ringing has also been obtained. For small charges, the approach to
thermal equilibrium is faster for larger charges. However, after the black hole
charge reaches a critical value, we get the opposite behavior for the imaginary
frequencies of the quasinormal modes. Some possible explanations concerning the
wiggle of the imaginary frequencies have been given. The picture of the
quasinormal modes depending on the multipole index has also been illustrated.

</DOC>
<DOC>
<DOCNO> 118189 </DOCNO>
The ALADIN Interactive Sky Atlas


  The Aladin interactive sky atlas, developed at CDS, is a service providing
simultaneous access to digitized images of the sky, astronomical catalogues,
and databases.
  The driving motivation is to facilitate direct, visual comparison of
observational data at any wavelength with images of the optical sky, and with
reference catalogues.
  The set of available sky images consists of the STScI Digitized Sky Surveys,
completed with high resolution images of crowded regions scanned at the MAMA
facility in Paris.
  A Java WWW interface to the system is available at:
http://aladin.u-strasbg.fr/

</DOC>
<DOC>
<DOCNO> 40679 </DOCNO>
Zenith angle distributions at Super-Kamiokande and SNO and the solution


  We have performed a detailed study of the zenith angle dependence of the
regeneration factor and distributions of events at SNO and SK for different
solutions of the solar neutrino problem. In particular, we discuss oscillatory
behaviour and the synchronization effect in the distribution for the LMA
solution, the parametric peak for the LOW solution, etc.. Physical
interpretation of the effects is given. We suggest a new binning of events
which emphasizes distinctive features of zenith angle distributions for the
different solutions. We also find the correlations between the integrated
day-night asymmetry and the rates of events in different zenith angle bins.
Study of these correlations strengthens the identification power of the
analysis.

</DOC>
<DOC>
<DOCNO> 118570 </DOCNO>
SN Ia Enrichment in Virgo Early-Type Galaxies from ROSAT and ASCA


  We analyzed nine X-ray bright Virgo early-type galaxies observed by both ASCA
and ROSAT. Through spatially resolved spectroscopy, we determined the radial
temperature profile and abundances of Mg, Si and Fe for six galaxies. The
temperature profiles are consistent with isothermal temperatures outside of a
cooler region at the galaxy center. We present new evidence for iron abundance
gradients in NGC4472 and NGC4649 and confirm the previous results on NGC4636.
Mg and Si abundance gradients on average are flatter compared to those of iron
and correspond to an underabundance of alpha-process elements at high Fe
values, while at low iron, the element ratios favor enrichment by type II SNe.
We explain the observed trend by the metallicity dependence of SN Ia metal
production and present constraints on the available theoretical modeling for
low-metallicity inhibition of SNe Ia (Kobayashi et al. 1998). Our results imply
a cut-off metallicity in the range 0.07-0.3 solar and require a lower limit of
0.3 solar on the Fe contribution of SN Ia. We estimate an SN Ia rate at the
centers of the brightest galaxies in our sample of ~0.08 (h_75)^3 SNu
(supernova units). The rates inferred from optical searches should be corrected
for the presence of `faint' SN Ia events, since these release limited metals
and therefore do not contribute significantly to the measured metallicity in
the X-ray gas. With this correction the present-epoch SN Ia rate in early-type
galaxies is 0.10+/-0.06 (h_75)^2 SNu (Cappellaro et al. 1997) and is therefore
comparable with the X-ray estimates. Abridged.

</DOC>
<DOC>
<DOCNO> 117338 </DOCNO>
Evaporative cooling of cesium atoms in the gravito-optical surface trap


  We report on cooling of an atomic cesium gas closely above an
evanescent-wave. Our first evaporation experiments show a temperature reduction
from 10muK down to 300nK along with a gain in phase-space density of almost two
orders of magnitude. In a series of measurements of heating and spin
depolarization an incoherent background of resonant photons in the
evanescent-wave diode laser light was found to be the limiting factor at this
stage.

</DOC>
<DOC>
<DOCNO> 68037 </DOCNO>
Gravitino production in hybrid inflationary models


  It has been recently shown that it is possible to excite gravitinos in an
expanding background due to a time varying scalar field oscillating at the
bottom of the inflationary potential. The two components of the gravitino,
namely helicity 1/2 and helicity 3/2, are excited differently due to the
presence of different time varying mass scales in the problem. In this paper we
analyse the production of both the helicities in a multi-chiral scenario, in
particular focusing on a general model of hybrid inflation. Fermion production
in hybrid models is very much different from that of the chaotic models
discussed so far in the literature. In this paper we give a full account of
gravitino production analytically and numerically. It is noticed that the
creation of gravitinos does not take place in the first few oscillations of the
inflaton field, rather the production is a gradual and delayed process. It
takes roughly 30-40 oscillations to build up the production and for the
saturation to take place it can even take longer time, depending on the model
parameters. We give an estimation of the reheat temperature and a brief
discussion upon back-reaction on the fermionic production, which could change
the gravitino abundance.

</DOC>
<DOC>
<DOCNO> 70617 </DOCNO>
Feasibility of Reconstructing the Quintessential Potential Using SNIa


  We investigate the feasibility of the method for reconstructing the equation
of state and the effective potential of the quintessence field from SNIa data.
We introduce a useful functional form to fit the luminosity distance with good
accuracy (the relative error is less than 0.1%). We assess the ambiguity in
reconstructing the equation of state and the effective potential which
originates from the uncertainty in $\Omega_M$. We find that the equation of
state is sensitive to the assumed $\Omega_M$, while the shape of the effective
potential is not. We also demonstrate the actual reconstruction procedure using
the data created by Monte-Carlo simulation. Future high precision measurements
of distances to thousands of SNIa could reveal the shape of the quintessential
potential.

</DOC>
<DOC>
<DOCNO> 101844 </DOCNO>
Diffusion time and splitting of separatrices for nearly integrable


  We consider the problem of Arnold's diffusion for nearly integrable
isochronous Hamiltonian systems. We prove a shadowing theorem which improves
the known estimates for the diffusion time. We also justify for three time
scales systems that the splitting of the separatrices is correctly predicted by
the Poincare'-Melnikov function.

</DOC>
<DOC>
<DOCNO> 70412 </DOCNO>
Results from pQCD for A+A collisions at RHIC & LHC energies


  This talk will discuss how to compute initial quantites in heavy ion
collisions at RHIC (200 AGeV) and at LHC (5500 AGeV) using perturbative QCD
(pQCD) by including the next-to-leading order (NLO) corrections and a dynamical
determination of the dominant physical scale. The initial numbers are converted
into final ones by assuming kinetic thermalization and adiabatic expansion.

</DOC>
<DOC>
<DOCNO> 99358 </DOCNO>
Transformations of ordinary differential equations via Darboux


  A new approach for obtaining the transformations of solutions of nonlinear
ordinary differential equations representable as the compatibility condition of
the overdetermined linear systems is proposed. The corresponding
transformations of the solutions of the overdetermined linear systems are
derived in the frameworks of the Darboux transformation technique.

</DOC>
<DOC>
<DOCNO> 150338 </DOCNO>
Gauge and gravitational interactions of non-BPS D-particles


  We study the gauge and gravitational interactions of the stable non-BPS
D-particles of the type I string theory. The gravitational interactions are
obtained using the boundary state formalism while the SO(32) gauge interactions
are determined by evaluating disk diagrams with suitable insertions of boundary
changing (or twist) operators. In particular the gauge coupling of a D-particle
is obtained from a disk with two boundary components produced by the insertion
of two twist operators. We also compare our results with the amplitudes among
the non-BPS states of the heterotic string which are dual to the D-particles.
After taking into account the known duality and renormalization effects, we
find perfect agreement, thus confirming at a non-BPS level the expectations
based on the heterotic/type I duality.

</DOC>
<DOC>
<DOCNO> 11598 </DOCNO>
Bilayer Coherent and Quantum Hall Phases: Duality and Quantum Disorder


  We consider a fully spin-polarized quantum Hall system with no interlayer
tunneling at total filling factor $\nu=1/k$ (where $k$ is an odd integer) using
the Chern-Simons-Ginzburg-Landau theory. Exploiting particle-vortex duality and
the concept of quantum disordering, we find a large number of possible
compressible and incompressible ground states, some of which may have relevance
to recent experiments of Spielman {\it et.al.}. We find interlayer coherent
compressible states without Hall quantization and interlayer-incoherent
incompressible with Hall quantization in addition to the usual $(k,k,k)$
Halperin states, which are both interlayer-coherent and incompressible.

</DOC>
<DOC>
<DOCNO> 12549 </DOCNO>
Nonequilibrium Critical Phenomena


  We discuss the non-equilibrium critical phenomena in liquids, and the models
for these phenomena based on local equilibrium and extended scaling
assumptions. Special situations are proposed for experimental tests of the
theory. Near-critical steady and transient states are reviewed. In a
near-critical steady state characterized by a temperature gradient, the theory
predicts strong nonequilibrium fluctuations at very large length scales. Close
to the critical point, this results in a nonlinear regime of heat conductivity.
A transient non-equilibrium state triggered by a rapid and large spatially
uniform perturbation of the critical liquid is considered. A step away from
criticality generates a free field with strong and decaying correlations in
initial state, while a step towards criticality initiates the increase of
fluctuations and of their correlation at the large scale edge of the critical
range. The approach to equilibrium is characterized by an equilibration length
&#61548;eq that depends on time t. The theory predicts a power law approach of
the temperature to the new equilibrium; the new critical exponents depend on
whether the temperature is initially increased or decreased.

</DOC>
<DOC>
<DOCNO> 120915 </DOCNO>
HI line measurements of pulsars towards the Galactic Centre and the


  We have measured 21-cm absorption and emission spectra in the direction of a
further 7 southern pulsars with the Parkes telescope to derive their kinematic
distances and to study the interstellar medium. For the first time we have
successfully obtained HI absorption measurements for PSRs J1602-5100,
J1740-3015 and J1745-3040. We have also significantly improved the sensitivity
and resolution on PSRs J1600-5044, J1752-2806, and J1825-0935, whose spectra
have previously been measured, and have corrected an error in the published
distance to PSR J1824-1945.
  Since the Frail & Weisberg summary of pulsar distances in 1990, a further 23
pulsars now have measured HI distances, mainly through the efforts of the
current group. We discuss the Taylor & Cordes electron density model in light
of these new measurements and find that, although the model towards the
Galactic Centre appears good, the line of sight through the Carina spiral arm
is poorly fit by the model.

</DOC>
<DOC>
<DOCNO> 80614 </DOCNO>
Reply to A. Patrascioiu's and E. Seiler's Comment on our paper


  Reply to comment appeared on hep-lat/9912014.

</DOC>
<DOC>
<DOCNO> 116260 </DOCNO>
Anomalous attenuation of extraordinary waves in ionosphere heating


  The results of experimental and theoretical study of anomalous attenuation of
probe extraordinary waves in experiments on modification of ionosphere by
powerful HF waves on "Sura" heating facility are presented. The experimental
data indicate significant attenuation of extraordinary waves which can be
explained as a result of multiple scattering of extraordinary waves on
small-scale random irregularities. The possibility of diagnostics of spectrum
of artificial irregularities from measurements of anomalous attenuation of
extraordinary waves is demonstrated.

</DOC>
<DOC>
<DOCNO> 10980 </DOCNO>
Ionic and electronic structure of sodium clusters up to N=59


  We determined the ionic and electronic structure of sodium clusters with even
electron numbers and 2 to 59 atoms in axially averaged and three-dimensional
density functional calculations. A local, phenomenological pseudopotential that
reproduces important bulk and atomic properties and facilitates structure
calculations has been developed. Photoabsorption spectra have been calculated
for $\mathrm{Na}_2$, $\mathrm{Na}_8$, and $\mathrm{Na}_9^+$ to
$\mathrm{Na}_{59}^+$. The consistent inclusion of ionic structure considerably
improves agreement with experiment. An icosahedral growth pattern is observed
for $\mathrm{Na}_{19}^+$ to $\mathrm{Na}_{59}^+$. This finding is supported by
photoabsorption data.

</DOC>
<DOC>
<DOCNO> 152276 </DOCNO>
Supercurrent Interactions in Noncommutative Yang-Mills and IIB Matrix


  It is known that noncommutative Yang-Mills is equivalent to IIB matrix model
with a noncommutative background, which is interpreted as a twisted reduced
model. In noncommutative Yang-Mills, long range interactions can be seen in
nonplanar diagrams after integrating high momentum modes. These interactions
can be understood as block-block interactions in the matrix model. Using this
relation, we consider long range interactions in noncommutative Yang-Mills
associated with fermionic backgrounds. Exchanges of gravitinos, which couple to
a supersymmetry current, are examined.

</DOC>
<DOC>
<DOCNO> 85315 </DOCNO>
Axion-dilaton-modulus gravity theory of Brans-Dicke-type and conformal


  Conformal symmetry is investigated within the context of
axion-dilaton-modulus theory of gravity of Brans-Dicke-type. A distinction is
made between general conformal symmetry and invariance under transformations of
the physical units. The conformal degree of symmetry of the theory is studied
when quantum fermion (lepton) modes with electromagnetic interaction are
considered. Based on the requirement of invariance of the physical laws under
general transformations of the units of measure, arguments are given that point
at a matter action with non-minimal coupling of the dilaton to the matter
fields as the most viable description of the world within the context of the
model studied. The geometrical implications of the results obtained are
discussed.

</DOC>
<DOC>
<DOCNO> 84836 </DOCNO>
Quantum evolution of near-extremal Reissner-Nordstrom black holes


  We study the near-horizon AdS_2\timesS^2 geometry of evaporating
near-extremal Reissner-Nordstrom black holes interacting with null matter. The
non-local (boundary) terms t_{\pm}, coming from the effective theory corrected
with the quantum Polyakov-Liouville action, are treated as dynamical variables.
We describe analytically the evaporation process which turns out to be
compatible with the third law of thermodynamics, i.e., an infinite amount of
time is required for the black hole to decay to extremality. Finally we comment
briefly on the implications of our results for the information loss problem.

</DOC>
<DOC>
<DOCNO> 119887 </DOCNO>
A proper motion study of the globular cluster M10


  We present the first proper motion study of M10 (NGC6254). Absolute proper
motions of about 532 stars in the field of the globular cluster M10 were
determined with respect to Hipparcos and ACT reference stars. In addition to
photographic plates of Bonn and Shanghai also wide field CCD observations as
second epoch plates were used. The wide field CCD observations show an accuracy
comparable to that of the photographic plates. A good coincidence of the
solutions based on reference stars from Hipparcos and from ACT was found. Our
final proper motions allow a sufficient separation of cluster and field stars.
Two population II Cepheids were confirmed to be members of M10. The absolute
proper motion of M10 was determined and combined with its distance from the Sun
and its radial velocity. The space motion and metallicity of M10 indicates the
characteristics of a halo object with an orbit reaching to a maximal z-distance
of less than 3kpc.

</DOC>
<DOC>
<DOCNO> 40123 </DOCNO>
Study of the spatial resolution achievable with the BTeV pixel sensors


  A Monte Carlo simulation has been developed to predict the spatial resolution
of silicon pixel detectors. The results discussed in this paper focus on the
unit cell geometry of 50 $\mu$m x 400 $\mu$m, as chosen for BTeV. Effects taken
into account include energy deposition fluctuations along the charged particle
path, diffusion, magnetic field and response of the front end electronics. We
compare our predictions with measurements from a recent test beam study
performed at Fermilab.

</DOC>
<DOC>
<DOCNO> 122403 </DOCNO>
COBE Constraints on a Compact Toroidal Low-density Universe


  In this paper, the cosmic microwave background (CMB) anisotropy in a
multiply-connected compact flat 3-torus model with the cosmological constant is
investigated. Using the COBE-DMR 4-year data, a full Bayesian analysis revealed
that the constraint on the topology of the flat 3-torus model with
low-matter-density is less stringent. As in compact hyperbolic models, the
large-angle temperature fluctuations can be produced as the gravitational
potential decays at the $\Lambda$-dominant epoch well after the last
scattering. The maximum allowed number $N$ of images of the cell (fundamental
domain) within the observable region at present is approximately 49 for
$\Omega_m=0.1$ and $\Omega_\Lambda=0.9$ whereas $N\sim8$ for $\Omega_m=1.0$ and
$\Omega_\Lambda=0$.

</DOC>
<DOC>
<DOCNO> 11314 </DOCNO>
Electron Energy Loss Spectroscopy of strongly correlated systems in


  We study the electron-energy loss spectra of strongly correlated electronic
systems doped away from half-filling using dynamical mean-field theory
($d=\infty$). The formalism can be used to study the loss spectra in the
optical (${\bf q=0}$) limit, where it is simply related to the optical
response, and hence can be computed in an approximation-free way in $d=\infty$.
We apply the general formalism to the one-band Hubbard model off $n=1$, with
inclusion of site-diagonal randomness to simulate effects of doping. The
interplay between the coherence induced plasmon feature and the
incoherence-induced high energy continuum is explained in terms of the
evolution in the local spectral density upon hole doping. Inclusion of static
disorder is shown to result in qualitative changes in the low-energy features,
in particular, to the overdamping of the plasmon feature, resulting in a
completely incoherent response. The calculated EELS lineshapes are compared to
experimentally observed EELS spectra for the normal state of the high-$T_{c}$
materials near optimal doping and good qualitative agreement is found.

</DOC>
<DOC>
<DOCNO> 40026 </DOCNO>
A Radio Telescope Search for Axions


  The axion is a hypothetical elementary particle and a cold dark matter
candidate. It could dominate potential wells of most astrophysical objects.
Axions spontaneously decay into nearly monochromatic microwave photons. We
present results from a radio telescope search for these axion decay photons of
mass between 298 and 363 micro-eV in Local Group dwarf galaxies. We report a
limit on the axion-to-two-photon coupling constant g > 1.0 x 10^(-9) GeV^(-1).

</DOC>
<DOC>
<DOCNO> 99580 </DOCNO>
On certain geometric and homotopy properties of closed symplectic


  The paper deals with relations between the Hard Lefschetz property,
(non)vanishing of Massey products and the evenness of odd-degree Betti numbers
of closed symplectic manifolds. It is known that closed symplectic manifolds
can violate all these properties (in contrast with the case of Kaehler
manifolds). However, the relations between such homotopy properties seem to be
not analyzed. This analysis may shed a new light on topology of symplectic
manifolds. In the paper, we summarize our knowledge in tables (different in the
simply-connected and in symplectically aspherical cases). Also, we discuss the
variation of symplectically harmonic Betti numbers on some 6-dimensional
manifolds.

</DOC>
<DOC>
<DOCNO> 169889 </DOCNO>
A Study of Quantum Error Correction by Geometric Algebra and


  Quantum error correcting codes enable the information contained in a quantum
state to be protected from decoherence due to external perturbations. Applied
to NMR, quantum coding does not alter normal relaxation, but rather converts
the state of a ``data'' spin into multiple quantum coherences involving
additional ancilla spins. These multiple quantum coherences relax at differing
rates, thus permitting the original state of the data to be approximately
reconstructed by mixing them together in an appropriate fashion. This paper
describes the operation of a simple, three-bit quantum code in the product
operator formalism, and uses geometric algebra methods to obtain the
error-corrected decay curve in the presence of arbitrary correlations in the
external random fields. These predictions are confirmed in both the totally
correlated and uncorrelated cases by liquid-state NMR experiments on
13C-labeled alanine, using gradient-diffusion methods to implement these
idealized decoherence models. Quantum error correction in weakly polarized
systems requires that the ancilla spins be prepared in a pseudo-pure state
relative to the data spin, which entails a loss of signal that exceeds any
potential gain through error correction. Nevertheless, this study shows that
quantum coding can be used to validate theoretical decoherence mechanisms, and
to provide detailed information on correlations in the underlying NMR
relaxation dynamics.

</DOC>
<DOC>
<DOCNO> 70699 </DOCNO>
Constraints for the nuclear sea quark distributions from the Drell-Yan


  Nuclear modifications to the Drell-Yan dilepton production cross sections in
p+A and A+A collisions in the leading twist approximation are caused by nuclear
effects in the parton distributions of bound nucleons. For non-isoscalar
nuclei, isospin corrections must also be considered. We calculate these effects
for p+A and Pb+Pb collisions at CERN SPS energies. Our goal is to place
constraints on nuclear effects in sea quark distributions in the region x >
0.2. We show that the net nuclear corrections remain small for p+A collisions
at E_lab=450 GeV. However, in Pb+Pb collisions at E_lab=158 AGeV, effects of >
20% are predicted at large M. The data collected by the NA50 collaboration
could thus be used to constrain the nuclear effects in the sea quark
distributions in the region of the EMC effect, x > 0.3.

</DOC>
<DOC>
<DOCNO> 101606 </DOCNO>
On the Existence of Critical Points to the Seiberg-Witten Functional


  Considering that the Seiberg-Witten functional satisfies the Palais-Smale
Condition, up to gauge equivalence, the Minimax Principle can be applied on the
moduli space to prove the existence of critical points, which correspond to
solutions of the second-order SW-equations, up to gauge equivalence.

</DOC>
<DOC>
<DOCNO> 120298 </DOCNO>
Mid-infrared interferometry on spectral lines: II. Continuum (dust)


  The U. C. Berkeley Infrared Spatial Interferometer has measured the
mid-infrared visibilities of the carbon star IRC+10216 and the red supergiant
VY CMa. The dust shells around these sources have been previously shown to be
time-variable, and these new data are used to probe the evolution of the dust
shells on a decade time-scale, complementing contemporaneous studies at other
wavelengths. Self-consistent, spherically-symmetric models at maximum and
minimum light both show the inner radius of the IRC+10216 dust shell to be much
larger (150 mas) than that expected from the dust condensation temperature,
implying that dust production has slowed or stopped in recent years.
Apparently, dust does not form every pulsational cycle (638 days), and these
mid-infrared results are consistent with recent near-IR imaging which indicates
little or no new dust production in the last three years (Tuthill et al 2000).
Spherically symmetric models failed to fit recent VY CMa data, implying that
emission from the inner dust shell is highly asymmetric and/or time-variable.

</DOC>
<DOC>
<DOCNO> 169779 </DOCNO>
Generalized Schmidt decomposition and classification of


  We prove for any pure three-quantum-bit state the existence of local bases
which allow to build a set of five orthogonal product states in terms of which
the state can be written in a unique form. This leads to a canonical form which
generalizes the two-quantum-bit Schmidt decomposition. It is uniquely
characterized by the five entanglement parameters. It leads to a complete
classification of the three-quantum-bit states. It shows that the right outcome
of an adequate local measurement always erases all entanglement between the
other two parties.

</DOC>
<DOC>
<DOCNO> 121724 </DOCNO>
Full-sky correlations of peaks in the microwave background


  We compute precise predictions for the two-point correlation function of
local maxima (or minima) in the temperature of the microwave background, under
the assumption that it is a random gaussian field. For a given power spectrum
and peak threshold there are no adjustable parameters, and since this analysis
does not make the small-angle approximation of Heavens & Sheth (1999), it is
essentially complete. We find oscillatory features which are absent in the
temperature autocorrelation function, and we also find that the small-angle
approximation to the peak-peak correlation function is accurate to better than
0.01 on all scales. These high-precision predictions can form the basis of a
sensitive test of the gaussian hypothesis with upcoming all-sky microwave
background experiments MAP and Planck, affording a thorough test of the
inflationary theory of the early Universe. To illustrate the effectiveness of
the technique, we apply it to simulated maps of the microwave sky arising from
the cosmic string model of structure formation, and compare with the bispectrum
as a non-gaussian discriminant. We also show how peak statistics can be a
valuable tool in assessing and statistically removing contamination of the map
by foreground point sources.

</DOC>
<DOC>
<DOCNO> 69867 </DOCNO>
A Lorentz covariant approach to the bound state problem


  The relativistic equivalent of the Schr\"odinger equation for a two particle
bound state having the total angular momentum $S$ is written in the form of a
Lorentz covariant set of equations (p_1^mu+p_2^mu+Omega^mu)Psi(p_1,p_2;P)
chi_S(\vec{p}_1,\vec{p}_2)=P^mu Psi(p_1,p_2;P) chi_S(\vec{p}_1,\vec{p}_2) where
the operators Omega^mu are the components of a 4-vector quasipotential. The
solution of this set is a stationary function representing the distribution of
spins and internal momenta in a reference frame where the momentum of the bound
system is P^\mu.
  The contribution of the operators Omega^mu to the bound state momentum is
assumed to be the 4-momentum of a vacuum-like effective field entering the
bound system as an independent component. It is shown that a state made of free
quarks and of the effective field has definite mass and can be normalized like
a single particle state.
  The generalization to the case of three or more particles is immediate.

</DOC>
<DOC>
<DOCNO> 100989 </DOCNO>
Explicit birational geometry of 3-folds, Foreword


  This is the Foreword to the book ``Explicit birational geometry of 3-folds'',
edited by A. Corti and M. Reid, CUP Jun 2000, ISBN: 0 521 63641 8, with papers
by K. Altmann, A. Corti, A.R. Iano-Fletcher, J. Koll\'ar, A.V. Pukhlikov and M.
Reid.
 One of the main achievements of algebraic geometry over the last 20 years is
the work of Mori and others extending minimal models and the Enriques--Kodaira
classification to 3-folds. This book is an integrated suite of papers centred
around applications of Mori theory to birational geometry. Four of the papers
(those by Pukhlikov, Fletcher, Corti, and the long joint paper Corti, Pukhlikov
and Reid) work out in detail the theory of birational rigidity of Fano 3-folds;
these contributions work for the first time with a representative class of Fano
varieties, 3-fold hypersurfaces in weighted projective space, and include an
attractive introductory treatment and a wealth of detailed computation of
special cases.

</DOC>
<DOC>
<DOCNO> 150767 </DOCNO>
Anomalies and symmetries of the regularized action


  We show that the Pauli-Villars regularized action for a scalar field in a
gravitational background in 1+1 dimensions has, for any value of the cutoff M,
a symmetry which involves non-local transformations of the regulator field plus
(local) Weyl transformations of the metric tensor. These transformations, an
extension to the regularized action of the usual Weyl symmetry transformations
of the classical action, lead to a new interpretation of the conformal anomaly
in terms of the (non-anomalous) Jacobian for this symmetry. Moreover, the
Jacobian is automatically regularized, and yields the correct result when the
masses of the regulators tend to infinity. In this limit the transformations,
which are non-local in a scale of 1/M, become the usual Weyl transformation of
the metric. We also present the example of the chiral anomaly in 1+1
dimensions.

</DOC>
<DOC>
<DOCNO> 71392 </DOCNO>
Towards Abelian-like formulation of the dual gluodynamics


  We consider gluodynamics in case when both color and magnetic charges are
present. We discuss first short distance physics, where only the fundamental
|Q|=1 monopoles introduced via the `t Hooft loop can be considered
consistently. We show that at short distances the external monopoles interact
as pure Abelian objects. This result can be reproduced by a Zwanziger-type
Lagrangian with an Abelian dual gluon. We introduce also an effective dual
gluodynamics which might be a valid approximation at distances where the
monopoles |Q|=2 can be considered as point-like as well. Assuming the monopole
condensation we arrive at a model which is reminiscent in some respect of the
Abelian Higgs model but, unlike the latter leaves space for the Casimir
scaling.

</DOC>
<DOC>
<DOCNO> 151235 </DOCNO>
Local Anomaly Cancellation, M-Theory Orbifolds and Phase-Transitions


  In this paper we consider orbifold compactifications of M-theory on $S^1/{\bf
Z}_2\times T^4/{\bf Z}_2$. We discuss solutions of the local anomaly matching
conditions by twisted vector, tensor and hypermultiplets confined on the local
orbifold six-planes. In addition we consider phase-transitions among different
solutions which are mediated by M-theory fivebranes which touch the local
orbifold planes and are converted there to gauge instantons.

</DOC>
<DOC>
<DOCNO> 121526 </DOCNO>
A radio-continuum and photoionization-model study of the two planetary


  Radio continuum observations at 1.4, 4.8 and 8.6 GHz of the two Planetary
Nebulae (PNe) in the Sagittarius dwarf galaxy reveal the elongated shape of
Wray 16-423 and the extreme compactness of He 2-436. He 2-436 is confirmed as
subject to local dust extinction.
  Photoionization models for both PNe are obtained from two different codes,
allowing theoretical uncertainties to be assessed. Wray 16-423, excited by a
star of Teff 1.07x10^5K, is an ellipsoidal, matter-bounded nebula, except for a
denser sector. He 2-436, excited by a 7x10^4K star, includes two
radiation-bounded shells, with the inner one possibly corresponding to a
transitory event. Both stars are on the same (H-burning) evolutionary track of
initial mass (1.2+/-0.1) Msun and may be twins, with the PN ejection of Wray
16-423 having occured ~1500 years before He 2-436.
  The PN abundances re-inforce the common origin of the parent stars,
indicating almost identical depletions with respect to solar for O, Ne, Mg, S,
Cl, Ar, and K (-0.55+/-0.07 dex), large identical overabundances for He and
strong overabundances for carbon, particularly in He2-436. Excess nitrogen
makes Wray 16-423 nearly a Type I PN. These PNe provide a means to calibrate
both metallicity and age of the Sagittarius stellar population, and they
confirm that the youngest, most metal-rich population has an age of 5Gyr and a
metallicity of [Fe/H]=-0.55, in agreement with the slope of the red giant
branch. (Abridged abstract)

</DOC>
<DOC>
<DOCNO> 101739 </DOCNO>
Tamagawa numbers of diagonal cubic surfaces of higher rank


  We consider diagonal cubic surfaces defined by an equation of the form
ax^3+by^3+cz^3+dt^3 = 0. Numerically, one can find all rational points of
height < B for B in the range of up to 100 000, thanks to a program due to D.
J. Bernstein. On the other hand, there are precise conjectures concerning the
constants in the asymptotics of rational points of bounded height due to Manin,
Batyrev and the authors. Changing the coefficients one can obtain cubic
surfaces with rank of the Picard group varying between 1 and 4. We check that
numerical data are compatible with the above conjectures. In a previous paper
we considered cubic surfaces with Picard groups of rank one with or without
Brauer-Manin obstruction to weak approximation. In this paper, we test the
conjectures for diagonal cubic surfaces with Picard groups of higher rank.

</DOC>
<DOC>
<DOCNO> 170303 </DOCNO>
Quantum cryptography using balanced homodyne detection


  We report an experimental quantum key distribution that utilizes balanced
homodyne detection, instead of photon counting, to detect weak pulses of
coherent light. Although our scheme inherently has a finite error rate, it
allows high-efficiency detection and quantum state measurement of the
transmitted light using only conventional devices at room temperature. When the
average photon number was 0.1, an error rate of 0.08 and "effective" quantum
efficiency of 0.76 were obtained.

</DOC>
<DOC>
<DOCNO> 9707 </DOCNO>
Systems with superabsorbing states


  We report on some extensive analysis of a recently proposed model [A.
Lipowski Phys. Rev. E {\bf 60}, 6255 (1999)] with infinitely many absorbing
states. By performing extensive Monte Carlo simulations we have determined
critical exponents and show strong evidence that this model is not in the
directed percolation universality class.
 The conjecture that this two-dimensional model exhibits a dimensional
reduction (behaving as one-dimensional directed percolation) is firmly
disproven.
 The reason for the model not exhibiting standard directed percolation scaling
behavior is traced back to the existence of what we call {\it superabsorbing
sites}, i.e. absorbing sites that cannot be directly activated by the presence
of neighboring activity in one or more than one directions.
 Supporting this claim we present two strong evidences: (i) in one dimension,
where superabsorbing sites do not appear at the critical point, the system
behaves as directed percolation, and (ii) in a modified two-dimensional
variation of the model, defined on a honeycomb lattice, for which
superabsorbing sites are very rarely observed, directed percolation behavior is
recovered. Finally, a parallel updating version of the model exhibiting a
nonequilibrium first-order transition is also reported.

</DOC>
<DOC>
<DOCNO> 71591 </DOCNO>
$K_{l4}$ at two-loops and CHPT predictions for $\pi\pi$-scattering


  We present the results from our two-loop calculations of masses,
decay-constants, vacuum-expectation-values and the $K_{\ell4}$ form-factors in
three-flavour Chiral Perturbation Theory (CHPT). We use this to fit the $L_i^r$
to two-loops and discuss the ensuing predictions for $\pi\pi$-threshold
parameters.

</DOC>
<DOC>
<DOCNO> 8719 </DOCNO>
Logarithmic corrections from ferromagnetic impurity ending bonds of open


  We analyze the logarithmic corrections due to ferromagnetic impurity ending
bonds of open spin 1/2 antiferromagnetic chains, using the density matrix
renormalization group technique. A universal finite size scaling $\sim {\frac 1
{L \log L}}$ for impurity contributions in the quasi-degenerate ground state
energy is demonstrated for a zigzag spin 1/2 chain at the critical next nearest
neighbor coupling and the standard Heisenberg spin 1/2 chain, in the long chain
limit. Using an exact solution for the latter case it is argued that one can
extract the impurity contributions to the entropy and specific heat from the
scaling analysis. It is also shown that a pure spin 3/2 open Heisenberg chain
belongs to the same universality class.

</DOC>
<DOC>
<DOCNO> 178577 </DOCNO>
Quadrupole shape invariants in the interacting boson model


  In terms of the Interacting Boson Model, shape invariants for the ground
state, formed by quadrupole moments up to sixth order, are studied in the
dynamical symmetry limits and, for the first time, over the whole structural
range of the IBM-1. The results are related to the effective deformation
parameters and their fluctuations in the geometrical model. New signatures that
can distinguish vibrator and gamma-soft rotor structures, and one that is
related to shape coexistence, are identified.

</DOC>
<DOC>
<DOCNO> 9477 </DOCNO>
Comment on ``Phase ordering in chaotic map lattices with conserved


  Angelini, Pellicoro, and Stramaglia [Phys. Rev. E {\bf 60}, R5021 (1999),
cond-mat/9907149] (APS) claim that the phase ordering of two-dimensional
systems of sequentially-updated chaotic maps with conserved ``order parameter''
does not belong, for large regions of parameter space, to the expected
universality class. We show here that these results are due to a slow crossover
and that a careful treatment of the data yields normal dynamical scaling.
Moreover, we construct better models, i.e. synchronously-updated coupled map
lattices, which are exempt from these crossover effects, and allow for the
first precise estimates of persistence exponents in this case.

</DOC>
<DOC>
<DOCNO> 80605 </DOCNO>
A nonperturbative study of three-dimensional phi^4 theory


  The spherical field formalism---a nonperturbative approach to quantum field
theory---was recently introduced and applied to phi^4 theory in two dimensions.
The spherical field method reduces a quantum field theory to a
finite-dimensional quantum mechanical system by expanding field configurations
in terms of spherical partial wave modes. We extend the formalism to phi^4
theory in three dimensions and demonstrate the application of the method by
analyzing the phase structure of this theory.

</DOC>
<DOC>
<DOCNO> 170219 </DOCNO>
Remarks on 2-q-bit states


  We distinguish six classes of families of locally equivalent states in a
straightforward scheme for classifying all 2-q-bit states; four of the classes
consist of two subclasses each. The simple criteria that we stated recently for
checking a given state's positivity and separability are justified, and we
discuss some important properties of Lewenstein-Sanpera decompositions. An
upper bound is conjectured for the sum of the degree of separability of a
2-q-bit state and its concurrence.

</DOC>
<DOC>
<DOCNO> 121782 </DOCNO>
The temperatures of dust-enshrouded AGNs


  A high density of massive dark objects (MDOs), probably supermassive black
holes, in the centres of nearby galaxies has been inferred from recent
observations. There are various indications that much of the accretion
responsible for producing these objects took place in dust-enshrouded active
galactic nuclei (AGNs). If so, then measurements of the intensity of background
radiation and the source counts in the far-infrared and submillimetre wavebands
constrain the temperature of dust in these AGNs. An additional constraint comes
from the hard X-ray background, if this is produced by accretion. One
possibility is that the dust shrouds surrounding the accreting AGNs are cold,
about 30 K. In this event, the dusty AGNs could be some subset of the
population of luminous distant sources discovered at 850 microns using the
SCUBA array on the JCMT, as proposed by Almaini et al. (1999). An alternative
is that the dust shrouds surrounding the accreting AGNs are much hotter (> 60
K). These values are closer to the dust temperatures of a number of
well-studied low-redshift ultraluminous galaxies that are thought to derive
their power from accretion. If the local MDO density is close to the maximum
permitted, then cold sources cannot produce this density without the
submillimetre background being overproduced if they accrete at high radiative
efficiency, and thus a hot population is required. If the dust-enshrouded
accretion occurred at similar redshifts to that taking place in unobscured
optical quasars, then a significant fraction of the far-infrared background
radiation measured by COBE at 140 microns, but very little of the
submilllimetre background at 850 microns, may have been produced by hot
dust-enshrouded AGNs which may have already been seen in recent X-ray surveys.

</DOC>
<DOC>
<DOCNO> 84132 </DOCNO>
Interpretation of intuitionistic solution of the vacuum Einstein


  The topos theory is a theory which is used for deciding a number of problems
of theory of relativity, gravitation and quantum physics. In the article
spherically symmetric solution of the vacuum Einstein equations in the
Intuitionistic theory of Gravitation at different stages of smooth topos ${\bf
Set}^{\bf L_{op}}$ is considered. Infinitesimal "weak" gravitational field can
be strong at some stagies, for which we have the additional dimensions. For
example, the cosmological constant is not constant with respect to additional
dimensions. Signature of space-time metric can depend of density of vacuum and
cosmological constant.

</DOC>
<DOC>
<DOCNO> 83218 </DOCNO>
On Modular Termination Proofs of General Logic Programs


  We propose a modular method for proving termination of general logic programs
(i.e., logic programs with negation). It is based on the notion of acceptable
programs, but it allows us to prove termination in a truly modular way. We
consider programs consisting of a hierarchy of modules and supply a general
result for proving termination by dealing with each module separately. For
programs which are in a certain sense well-behaved, namely well-moded or
well-typed programs, we derive both a simple verification technique and an
iterative proof method. Some examples show how our system allows for greatly
simplified proofs.

</DOC>
<DOC>
<DOCNO> 11401 </DOCNO>
Comment on "Localization and the mobility edge in one-dimensional


  The equation for the wave-function localization length in terms of the
two-point correlation function of a weak random potential in 1D (F. M. Izrailev
and A. A. Krokhin, Phys. Rev. Lett. vol. 82, 4062 (1999)) is rederived using
the standard weak-localization theory. I propose a modified algorithm for
generation of arbitrary correlated random potentials, and show that numerical
calculation of the localization length in a specific correlated disorder in 1D
is then in accord with the analytic expression, removing the discrepancy noted
in the above Letter.

</DOC>
<DOC>
<DOCNO> 70151 </DOCNO>
Matching the observational value of the cosmological constant


  A simple model is introduced in which the cosmological constant is
interpreted as a true Casimir effect on a scalar field filling the universe
(e.g. $\mathbf{R} \times \mathbf{T}^p\times \mathbf{T}^q$, $\mathbf{R} \times
\mathbf{T}^p\times \mathbf{S}^q, ...$). The effect is driven by compactifying
boundary conditions imposed on some of the coordinates, associated both with
large and small scales. The very small -but non zero- value of the cosmological
constant obtained from recent astrophysical observations can be perfectly
matched with the results coming from the model, by playing just with the
numbers of -actually compactified- ordinary and tiny dimensions, and being the
compactification radius (for the last) in the range $(1-10^3) l_{Pl}$, where
$l_{Pl}$ is the Planck length. This corresponds to solving, in a way, what has
been termed by Weinberg the {\it new} cosmological constant problem. Moreover,
a marginally closed universe is favored by the model, again in coincidence with
independent analysis of the observational results.

</DOC>
<DOC>
<DOCNO> 67949 </DOCNO>
Cosmology of Randall-Sundrum models with an extra dimension stabilized


  We provide the cosmological solutions for Randall-Sundrum models with the
bulk energy-momentum $\hat T^5_5$ incorporated. It alters the Friedmann
equation for the brane scale factor. We make a specific choice of $\hat T^5_5$
which is adjusted to stabilize the extra dimension. This makes it possible to
compactify the extra dimension with a single positive tension brane, and this
model provides a RS-type solution to the cosmological constant problem. When
the same idea is applied to the RS model with two branes, the wrong sign of
Friedmann equation for the negative tension brane can be resolved and usual FRW
cosmology is reproduced for the brane.

</DOC>
<DOC>
<DOCNO> 8162 </DOCNO>
Many Body Diffusion and Interacting Electrons in a Harmonic Confinement


  We present numerically exact energy estimates for two-dimensional electrons
in a parabolic confinement. By application of an extension of the recently
introduced many-body diffusion algorithm, the ground-state energies are
simulated very efficiently. The new algorithm relies on partial
antisymmetrization under permutation of particle coordinates. A comparison is
made with earlier theoretical results for that system.

</DOC>
<DOC>
<DOCNO> 13541 </DOCNO>
Phase Diagrams of the Harper Map and the Golden Staircase


  We present phase diagrams of the Harper map, which is equivalent to the
problem of Bloch electrons in a uniform magnetic field (Azbel-Hofstadter
model). We consider the cases where the magnetic flux $\omega$ assumes either
the continued fraction approximations towards the golden mean or the golden
mean itself. The phase diagrams for rational values of $\omega$ show a finite
number of Arnol'd tongues of localized electronic states with rational winding
numbers and regions of extended phases in between them. For the particular case
of $\omega = \frac{\sqrt{5}-1}{2}$, we find an infinite number of Arnol'd
tongues of localized phases with extended phases in between. In this case, the
study of the winding number gives rise to a Golden Staircase, where the
plateaux represent localized phases with winding numbers equal to sums of
powers of the golden mean. We also present evidence of the existence of an
infinite number of strange nonchaotic attractors for $\epsilon=1$ in points
analogous to critical points in the pressure-temperature phase diagram of the
water.

</DOC>
<DOC>
<DOCNO> 118377 </DOCNO>
Bulges


  We model the evolution of the galactic bulge and of the bulges of a selected
sample of external spiral galaxies, via the multiphase multizone evolution
model. We address a few questions concerning the role of the bulges within
galactic evolution schemes and the properties of bulge stellar populations. We
provide solutions to the problems of chemical abundances and spectral indices,
the two main observational constraints to bulge structure.

</DOC>
<DOC>
<DOCNO> 117030 </DOCNO>
The Approach to Ergodicity in Monte Carlo Simulations


  The approach to the ergodic limit in Monte Carlo simulations is studied using
both analytic and numerical methods. With the help of a stochastic model, a
metric is defined that enables the examination of a simulation in both the
ergodic and non-ergodic regimes. In the non-ergodic regime, the model implies
how the simulation is expected to approach ergodic behavior analytically, and
the analytically inferred decay law of the metric allows the monitoring of the
onset of ergodic behavior. The metric is related to previously defined measures
developed for molecular dynamics simulations, and the metric enables the
comparison of the relative efficiencies of different Monte Carlo schemes.
Applications to Lennard-Jones 13-particle clusters are shown to match the model
for Metropolis, J-walking and parallel tempering based approaches. The relative
efficiencies of these three Monte Carlo approaches are compared, and the decay
law is shown to be useful in determining needed high temperature parameters in
parallel tempering and J-walking studies of atomic clusters.

</DOC>
<DOC>
<DOCNO> 119193 </DOCNO>
Constraining the Location of Microlensing Objects by using the Finite


  We propose a new method to constrain the location of microlensing objects
using EAGLE (Extremely Amplified Gravitational LEnsing) events. We have
estimated the rate of EAGLE events by taking the finite-source effect in to
account. We found that the EAGLE event rate for using a 1-m class telescope w
hose limiting magnitude is $V \sim 21$ is the same as or higher than that of
the ordinary microlensing events which have been found to date. We have also
found that the fraction of transit EAGLE events is large enough to detect:
between $4 \sim 80 % $ depending on the lens location. Since the lens proper
motion can be measured for a transit event, one can distinguish whether the
lens is a MACHO (MAssive Compact Halo Object) in our hal o or one of the known
stars in the Large Magellanic Cloud (LMC) from the proper motion measurement
for each transit EAGLE event. Moreover, we show that the fraction of transit
EAGLEs in all EAGLE events signif icantly depends on the lensing locations: the
transit EAGLE fraction for the sel f-lensing case is $2 \sim 15$ times larger
than that for halo MACHOs. Thus, one can constrain the location of lens objects
by the statistics of the tr ansit events fraction. We show that we can
reasonably expect $0 \sim 6$ transit events out of 21 EAGLE events in 3 years.
We can also constrain the lens population properties at a gre ater than 99%
confidence level depending on the number of transit events de tected. We also
present the duration of EAGLE events, and show how an hourly ob servational
mode is more suitable for an EAGLE event search program.

</DOC>
<DOC>
<DOCNO> 9125 </DOCNO>
Anomalous rotational properties of Bose-Einstein condensates in


  We study the rotational properties of a Bose-Einstein condensate confined in
a rotating harmonic trap for different trap anisotropies. Using simple
arguments, we derive expressions for the velocity field of the quantum fluid
for condensates with or without vortices. While the condensed gas describes
open spiraling trajectories, on the frame of reference of the rotating trap the
motion of the fluid is against the trap rotation. We also find explicit
formulae for the angular momentum and a linear and Thomas-Fermi solutions for
the state without vortices. In these two limits we also find an analytic
relation between the shape of the cloud and the rotation speed. The predictions
are supported by numerical simulations of the mean field Gross-Pitaevskii
model.

</DOC>
<DOC>
<DOCNO> 170662 </DOCNO>
Quantum Rate-Distortion Theory for I.I.D. Sources


  We formulate quantum rate-distortion theory in the most general setting where
classical side information is included in the tradeoff. Using a natural
distortion measure based on entanglement fidelity and specializing to the case
of an unrestricted classical side channel, we find the exact quantum
rate-distortion function for a source of isotropic qubits. An upper bound we
believe to be exact is found in the case of biased sources. We establish that
in this scenario optimal rate-distortion codes produce no entropy exchange with
the environment of any individual qubit.

</DOC>
<DOC>
<DOCNO> 84887 </DOCNO>
Fractal Scales in a Schwarzschild Atmosphere


  Recently, Glass and Krisch have extended the Vaidya radiating metric to
include both a radiation fluid and a string fluid [1999 Class. Quantum Grav.
vol 16, 1175]. Mass diffusion in the extended Schwarzschild atmosphere was
studied. The continuous solutions of classical diffusive transport are believed
to describe the envelope of underlying fractal behavior. In this work we
examine the classical picture at scales on which fractal behavior might be
evident.

</DOC>
<DOC>
<DOCNO> 121564 </DOCNO>
The effects of seeing on Sersic profiles


  The effects of seeing on the parameters of the S\`ersic profile are studied
in an analytical form using a Gaussian point spread function. The surface
brightness of S\`ersic profiles is proportional (in magnitudes) to $r^{1/n}$.
The parameter $n$ serves to classify the type of profile and is related to the
central luminosity concentration. It is the parameter most affected by seeing;
furthermore, the value of $n$ that can be measured is always smaller than the
real one. It is shown that the luminosity density of the S\`ersic profile with
$n$ less than 0.5 has a central depression, which is physically unlikely. Also,
the intrinsic ellipticity of the sources has been taken into account and we
show that the parameters are dependent when the effects of seeing are
non-negligible. Finally, a prescription for correcting raw effective radii,
central intensities and $n$ parameters is given.

</DOC>
<DOC>
<DOCNO> 100296 </DOCNO>
Hypothesis Testing with the General Source


  The asymptotically optimal hypothesis testing problem with the general
sources as the null and alternative hypotheses is studied under
exponential-type error constraints on the first kind of error probability. Our
fundamental philosophy in doing so is first to convert all of the hypothesis
testing problems completely to the pertinent computation problems in the large
deviation-probability theory. It turns out that this kind of methodologically
new approach enables us to establish quite compact general formulas of the
optimal exponents of the second kind of error and correct testing
probabbilities for the general sources including all nonstationary and/or
nonergodic sources with arbitrary abstract alphabet (countable or uncountable).
Such general formulas are presented from the information-spectrum point of
view.

</DOC>
<DOC>
<DOCNO> 122023 </DOCNO>
J1343+3758: The third largest FRII-type radio galaxy


  A radio source of the Fanaroff--Riley type II with the angular size of 11.3
arc min is identified with an optical galaxy at z=0.229. Thus, the projected
linear extent of the radio structure is 3.14 Mpc which makes it the third
largest classical double radio source known after 3C236 and WNB2147+816. The
high-frequency VLA observations, a galaxy identification and its optical
spectroscopy are reported. The equipartition magnetic field and energy density
in the source is calculated and compared with corresponding parameters of other
giants known, indicating that either parameter of the source investigated is
extremely low. On the other hand, the age estimate of relativistic electrons
and the advance speed of the lobe material are comparable to the respective
parameters characterizing other low-luminosity giant sources, as well as much
smaller and brighter 3CR sources. The environment analysis suggests that
J1343+3758 lies in a significantly poor region of intergalactic medium.

</DOC>
<DOC>
<DOCNO> 10173 </DOCNO>
Fluctuations and the existence of potential in dissipative semiclassical


  We examine the weak noise limit of an overdamped dissipative system within a
semiclassical description and show how quantization influences the growth and
decay of fluctuations of the thermally equilibrated systems. We trace its
origin in a semiclassical counterpart of the generalized potential for the
dissipative system.

</DOC>
<DOC>
<DOCNO> 9342 </DOCNO>
Momentum and doping dependence of the electron spectrum and ($\pi$,0)


  The momentum and doping dependence of the electron spectrum of copper oxide
materials in the underdoped regime is studied within the t-J model. It is shown
that the pseudogap opens near ($\pi$,0) point in the Brillouin zone, and the
electron dispersion exhibits the flat band around ($\pi$,0), which are
consistent with the experiments.

</DOC>
<DOC>
<DOCNO> 151257 </DOCNO>
Multi-Brane Worlds and modification of gravity at large scales


  We discuss the implications of multi-brane constructions involving
combinations of positive and negative tension brane and show how anomalously
light KK states emerge when negative tension ''-'' branes are sandwiched
between ''+'' branes. We present a detailed study of a ''+--+'' brane
assignment which interpolates between two models that have been previously
proposed in which gravity is modified at large scales due to the anomalously
light states. We show that it has the peculiar characteristic that gravity
changes from four dimensional (4D) to 5D at large distances and returns to 4D
at even larger scales. We also consider a crystalline universe which leads to a
similar structure for gravity. The problems associated with intermediate
negative tension branes are discussed and a possible resolution suggested.

</DOC>
<DOC>
<DOCNO> 11382 </DOCNO>
Half-Integer Winding Number Solutions to the Landau-Ginzburg-Higgs


  New solutions to the abelian U(1) Higgs model, corresponding to vortices of
integer and half-integer winding number bound onto the edges of domain walls
and possibly surrounded by annular current flows, are described, based on a
fine-grained analysis of the topology of such configurations in spacetime. The
existence of these states, which saturate BPS bounds in specific limits and are
quite reminiscent of D-branes and membranes in general, could have interesting
and some important consequences in a wide range of physical contexts. For
instance, they raise the possibility that for some regimes of couplings the
usual vortex of unit winding number would split into two vortices each of
one-half winding number bound by a domain wall. A similar approach may also be
relevant to other known topological states of field theory.

</DOC>
<DOC>
<DOCNO> 68752 </DOCNO>
Branching Ratio and CP Violation of B to pi pi Decays in Perturbative


  We calculate the branching ratios and CP asymmetries for B^0 to pi^+pi^-, B^+
to pi^+pi^0 and B^0 to pi^0pi^0 decays, in a perturbative QCD approach. In this
approach, we calculate non-factorizable and annihilation type contributions, in
addition to the usual factorizable contributions. We found that the
annihilation diagram contributions are not very small as previous argument. Our
result is in agreement with the measured branching ratio of B to pi^+pi^- by
CLEO collaboration. With a non-negligible contribution from annihilation
diagrams and a large strong phase, we predict a large direct CP asymmetry in
B^0 to pi^+pi^-, and pi^0pi^0, which can be tested by the current running B
factories.

</DOC>
<DOC>
<DOCNO> 10985 </DOCNO>
Pinholes May Mimic Tunneling


  Interest in magnetic-tunnel junctions has prompted a re-examination of
tunneling measurements through thin insulating films. In any study of
metal-insulator-metal trilayers, one tries to eliminate the possibility of
pinholes (small areas over which the thickness of the insulator goes to zero so
that the upper and lower metals of the trilayer make direct contact). Recently,
we have presented experimental evidence that ferromagnet-insulator-normal
trilayers that appear from current-voltage plots to be pinhole-free may
nonetheless in some cases harbor pinholes. Here, we show how pinholes may arise
in a simple but realistic model of film deposition and that purely classical
conduction through pinholes may mimic one aspect of tunneling, the exponential
decay in current with insulating thickness.

</DOC>
<DOC>
<DOCNO> 11318 </DOCNO>
Coherent Tunneling in Fe-8 Molecular Nanomagnets: Response to the


  Response to the Comment by Bellessa (arXiv:cond-mat/0006441).

</DOC>
<DOC>
<DOCNO> 101498 </DOCNO>
Cube-root boundary fluctuations for droplets in random cluster models


  For a family of bond percolation models on Z^{2} that includes the
Fortuin-Kasteleyn random cluster model, we consider properties of the
``droplet'' that results, in the percolating regime, from conditioning on the
existence of an open dual circuit surrounding the origin and enclosing at least
(or exactly) a given large area A. This droplet is a close surrogate for the
one obtained by Dobrushin, Koteck\'y and Shlosman by conditioning the Ising
model; it approximates an area-A Wulff shape. The local part of the deviation
from the Wulff shape (the ``local roughness'') is the inward deviation of the
droplet boundary from the boundary of its own convex hull; the remaining part
of the deviation, that of the convex hull of the droplet from the Wulff shape,
is inherently long-range. We show that the local roughness is described by at
most the exponent 1/3 predicted by nonrigorous theory; this same prediction has
been made for a wide class of interfaces in two dimensions. Specifically, the
average of the local roughness over the droplet surface is shown to be
O(l^{1/3}(\log l)^{2/3}) in probability, where l = \sqrt{A} is the linear scale
of the droplet. We also bound the maximum of the local roughness over the
droplet surface and bound the long-range part of the deviation from a Wulff
shape, and we establish the absense of ``bottlenecks,'' which are a form of
self-approach by the droplet boundary, down to scale \log l. Finally, if we
condition instead on the event that the total area of all large droplets inside
a finite box exceeds A, we show that with probability near 1 for large A, only
a single large droplet is present.

</DOC>
<DOC>
<DOCNO> 40165 </DOCNO>
Observation of the phi to pi+pi-pi+pi- Decay


  Using 11.6 pb^{-1} of data collected in the energy range 0.984--1.06 GeV by
CMD-2 at VEPP-2M, the cross section of the reaction e+e- to pi+pi-pi+pi- has
been studied. For the first time an interference pattern was observed in the
energy dependence of the cross section near the phi meson. The branching ratio
of the phi to pi+pi-pi+pi- decay double suppressed by the G-parity and OZI rule
is measured Br(phi to pi+pi-pi+pi-) = (3.93 +- 1.74 +- 2.14) \cdot 10^{-6}. The
upper limits have been placed for the decays phi to pi+pi-pi+pi-pi0 and phi to
eta pi+pi-
  Br(phi to pi+pi-pi+pi-pi0) < 4.6 \cdot 10^{-6} 90% CL,
  Br(phi to eta pi+pi-) < 1.8 \cdot 10^{-5} 90% CL.

</DOC>
<DOC>
<DOCNO> 150655 </DOCNO>
Aspects of holography and rotating AdS black holes


  A comparison is made between the thermodynamics of weakly and strongly
coupled Yang-Mills with fixed angular momentum. The free energy of the strongly
coupled Yang-Mills is calculated by using a dual supergravity description
corresponding to a rotating black hole in an Anti de Sitter (AdS) background.
All thermodynamic quantities are shown have the same ratio of 3/4 (independent
of angular momentum) between strong and weak coupling.

</DOC>
<DOC>
<DOCNO> 169906 </DOCNO>
Uncertainty rescued: Bohr's complementarity for composite systems


  Generalized uncertainty relations may depend not only on the commutator
relation of two observables considered, but also on mutual correlations, in
particular, on entanglement. The equivalence between the uncertainty relation
and Bohr's complementarity thus holds in a much broader sense than anticipated.

</DOC>
<DOC>
<DOCNO> 120150 </DOCNO>
Constraints on Type Ia Supernovae from Near Infrared Spectra


  We describe a research program to improve the understanding of Type Ia
Supernovae (SNe Ia) by modeling and observing near infrared (NIR) spectra of
these events. The NIR between 0.9 microns and 2.5 microns is optimal for
examining certain products of the SNe Ia explosion that may be blended or
obscured in other spectral regions. NIR analysis will enable us to place
important constraints on the physical properties of SNe Ia progenitors and
their explosion dynamics. These are critical steps toward understanding the
physics of Type Ia Supernovae. We have identified features in NIR spectra of
SNe Ia that discriminate between Population I and Population II progenitors.
These features can significantly restrict the evolutionary history of SNe Ia.
We also examine certain products of the nuclear burning that enable us to place
constraints on the propagation of nuclear burning during the explosion, and on
the behavior of the burning front during the event. We will be able to
differentiate between the several explosion models for SNe Ia.

</DOC>
<DOC>
<DOCNO> 102008 </DOCNO>
Semi-infinite Hodge structures and mirror symmetry for projective spaces


  We express total set of rational Gromov-Witten invariants of projective
spaces via periods of variations of semi-infinite Hodge structure associated
with their mirror partners.

</DOC>
<DOC>
<DOCNO> 99706 </DOCNO>
The ideal Thurston-Andreev theorem and triangulation production


  This paper contains a generalization of the convex ideal case of the
Thurston-Andreev theorem when the genus is greater than 1. The heart of the
paper concerns taking formal angle data on a surface and ``conformally
flowing'' this formal angle data to uniquely associated uniform angle data.
This flow turns out to be the gradient of an objective function related in a
rather magical way to hyperbolic volume.

</DOC>
<DOC>
<DOCNO> 39619 </DOCNO>
Laser cooling of electron beams at linear colliders


  A method of electron beam cooling is considered which can be used for linear
colliders. The electron beam is cooled during collision with focused powerful
laser pulse. The ultimate transverse emittances are much below those achievable
by other methods. This method is especially useful for high energy gamma-gamma
colliders. In this paper we review and analyse limitations in this method, also
discuss a new method of obtaining very high laser powers required for the laser
cooling, radiation conditions and finaly present a possible scheme for the
laser cooling of electron beams.

</DOC>
<DOC>
<DOCNO> 84347 </DOCNO>
Nonstatic global string in Brans-Dicke theory


  Gravitational field of a nonstatic global string has been studied in the
context of Brans-Dicke theory of gravity. Both the metric components and the BD
scalar field are assumed to be nonseparable functions of time and space.The
spacetime may or may not have any singularity at a finite distance from the
string core but the singularity at a particular time always remains. It has
been shown that the spacetime exhibits both outgoing and incoming gravitational
radiation.

</DOC>
<DOC>
<DOCNO> 117545 </DOCNO>
Quantitative analysis of WC stars: Constraints on neon abundances from


  Neon abundances are derived in four Galactic WC stars -- gamma Vel (WR11,
WC8+O7.5III), HD156385 (WR90, WC7), HD192103 (WR135, WC8), and WR146 (WC5+O8) -
using mid-infrared fine structure lines obtained with ISO/SWS. Stellar
parameters for each star are derived using a non-LTE model atmospheric code
(Hillier & Miller 1998) together with ultraviolet (IUE), optical (INT, AAT) and
infrared (UKIRT, ISO) spectroscopy. In the case of gamma Vel, we adopt results
from De Marco et al. (2000), who followed an identical approach.
  ISO/SWS datasets reveal the [NeIII] 15.5um line in each of our targets, while
[NeII] 12.8um, [SIV] 10.5um and [SIII] 18.7um are observed solely in gamma Vel.
Using a method updated from Barlow et al. (1988) to account for clumped winds,
we derive Ne/He=3-4x10^-3 by number, plus S/He=6x10^-5 for gamma Vel. Neon is
highly enriched, such that Ne/S in gamma Vel is eight times higher than cosmic
values. However, observed Ne/He ratios are a factor of two times lower than
predictions of current evolutionary models of massive stars. An imprecise
mass-loss and distance were responsible for the much greater discrepancy in
neon content identified by Barlow et al.
  Our sample of WC5--8 stars span a narrow range in T* (=55--71kK), with no
trend towards higher temperature at earlier spectral type, supporting earlier
results for a larger sample by Koesterke & Hamann (1995). Stellar luminosities
range from 100,000 to 500,000 Lo, while 10^-5.1 < Mdot/(Mo/yr) < 10^-4.5,
adopting clumped winds, in which volume filling factors are 10%. In all cases,
wind performance numbers are less than 10, significantly lower than recent
estimates. Carbon abundances span 0.08 < C/He < 0.25 by number, while oxygen
abundances remain poorly constrained.

</DOC>
<DOC>
<DOCNO> 119172 </DOCNO>
Substructure and halo density profiles in a Warm Dark Matter Cosmology


  We performed a series of high-resolution simulations designed to study the
substructure of Milky Way-size galactic halos (host halos) and the density
profiles of halos in a warm dark matter (WDM) scenario with a non-vanishing
cosmological constant. The virial masses of the host halos range from 3.5 x
10^12 to 1.7 x 10^12 solar masses and they have more than 10^5 particles each.
A key feature of the WDM power spectrum is the free-streaming length R_f which
fixes an additional parameter for the model of structure formation. We analyze
the substructure of host halos using three R_f values: 0.2, 0.1, and 0.05 Mpc
and compare results to the predictions of the cold dark matter (CDM) model. We
find that guest halos (satellites) do form in the WDM scenario but are more
easily destroyed by dynamical friction and tidal disruption than their
counterparts in a CDM model. The small number of guest halos that we find
within the virial radii of host halos at z = 0 in the WDM models is the result
of a less efficient halo accretion and a higher satellite destruction rate.
Under the assumption that each guest halo hosts a luminous galaxy, we find that
the observed circular velocity function of satellites around the Milky Way and
Andromeda is well described by the R_f = 0.1 Mpc WDM model. In the R_f =
0.1-0.2 Mpc models, the surviving subhalos at z=0 have an average concentration
parameter c_1/5 which is approximately twice smaller than that of the
corresponding CDM subhalos. This difference, very likely, produces the higher
satellite destruction rate found in the WDM models. The density profile of host
halos is well described by the NFW fit whereas guest halos show a wide variety
of density profiles (abridged).

</DOC>
<DOC>
<DOCNO> 119531 </DOCNO>
New NLS1 galaxies detected among RASS galaxies


  Six Narrow-Line Seyfert 1 galaxies have been discovered in optical follow-up
spectroscopy of nuclei of galaxies selected for their high X-ray flux in the
ROSAT All Sky Survey. We give X-ray and optical parameters of the sources and
show optical spectra.

</DOC>
<DOC>
<DOCNO> 116911 </DOCNO>
Physics Design Considerations of Diagnostic X Beam Transport System


  Diagnostic X (D-X) transport system would extract the beam from the
downstream transport line of the second- axis of the Dual Axis Radiographic
Hydrodynamic Test facility (DARHT-II) and transport this beam to the D-X firing
point via four branches of the beamline in order to provide four lines of sight
for x-ray radiography. The design goal is to generate four DARHT-II-like x-ray
pulses on each line of sight. In this paper, we discuss several potential beam
quality degradation processes in the passive magnet lattice beamline and
indicate how they constrain the D-X beamline design parameters, such as the
background pressure, the pipe size, and the pipe material

</DOC>
<DOC>
<DOCNO> 116721 </DOCNO>
Evolutionarily Stable Strategies in Quantum Games


  Evolutionarily Stable Strategy (ESS) in classical game theory is a refinement
of Nash equilibrium concept. We investigate the consequences when a small group
of mutants using quantum strategies try to invade a classical ESS in a
population engaged in symmetric bimatrix game of Prisoner's Dilemma. Secondly
we show that in an asymmetric quantum game between two players an ESS pair can
be made to appear or disappear by resorting to entangled or unentangled initial
states used to play the game even when the strategy pair remains a Nash
equilibrium in both forms of the game.

</DOC>
<DOC>
<DOCNO> 122906 </DOCNO>
High-sensitivity observations of solar flare decimeter radiation


  A new acousto-optic radio spectrometer has observed the 1 - 2 GHz radio
emission of solar flares with unprecedented sensitivity. The number of detected
decimeter type III bursts is greatly enhanced compared to observations by
conventional spectrometers observing only one frequency at the time. The
observations indicate a large number of electron beams propagating in dense
plasmas. For the first time, we report weak, reversed drifting type III bursts
at frequencies above simultaneous narrowband decimeter spikes. The type III
bursts are reliable signatures of electron beams propagating downward in the
corona, apparently away from the source of the spikes. The observations
contradict the most popular spike model that places the spike sources at the
footpoints of loops. Conspicuous also was an apparent bidirectional type U
burst forming a fish-like pattern. It occurs simultaneously with an intense
U-burst at 600-370 MHz observed in Tremsdorf. We suggest that it intermodulated
with strong terrestrial interference (cellular phones) causing a spurious
symmetric pattern in the spectrogram at 1.4 GHz. Symmetric features in the 1 -
2 GHz range, some already reported in the literature, therefore must be
considered with utmost caution.

</DOC>
<DOC>
<DOCNO> 70116 </DOCNO>
(3+1)-dimensional relativistic hydrodynamical expansion of hot and dense


  A full (3+1)-dimensional calculation using the Lagrangian hydrodynamics is
proposed for relativistic nuclear collisions. The calculation enables us to
evaluate anisotropic flow of hadronic matter which appears in non-central
and/or asymmetrical relativistic nuclear collisions. Applying hydrodynamical
calculations to the deformed uranium collisions at AGS energy region, we
discuss the nature of space-time structure and particle distributions in
detail.

</DOC>
<DOC>
<DOCNO> 10442 </DOCNO>
Symmetric Versus Nonsymmetric Structure of the Phosphorus Vacancy on


  The atomic and electronic structure of positively charged P vacancies on
InP(110) surfaces is determined by combining scanning tunneling microscopy,
photoelectron spectroscopy, and density-functional theory calculations. The
vacancy exhibits a nonsymmetric rebonded atomic configuration with a charge
transfer level 0.75+-0.1 eV above the valence band maximum. The scanning
tunneling microscopy (STM) images show only a time average of two degenerate
geometries, due to a thermal flip motion between the mirror configurations.
This leads to an apparently symmetric STM image, although the ground state
atomic structure is nonsymmetric.

</DOC>
<DOC>
<DOCNO> 170169 </DOCNO>
Strict detector-efficiency bounds for n-site Clauser-Horne inequalities


  An analysis of detector-efficiency in many-site Clauser-Horne inequalities is
presented, for the case of perfect visibility. It is shown that there is a
violation of the presented n-site Clauser-Horne inequalities if and only if the
efficiency is greater than n/(2n-1). Thus, for a two-site two-setting
experiment there are no quantum-mechanical predictions that violate local
realism unless the efficiency is greater than 2/3. Secondly, there are n-site
experiments for which the quantum-mechanical predictions violate local realism
whenever the efficiency exceeds 1/2.

</DOC>
<DOC>
<DOCNO> 71516 </DOCNO>
Gravitational Higgs Mechanism


  We discuss the gravitational Higgs mechanism in domain wall background
solutions that arise in the theory of 5-dimensional Einstein-Hilbert gravity
coupled to a scalar field with a non-trivial potential. The scalar fluctuations
in such backgrounds can be completely gauged away, and so can be the
graviphoton fluctuations. On the other hand, we show that the graviscalar
fluctuations do not have normalizable modes. As to the 4-dimensional graviton
fluctuations, in the case where the volume of the transverse dimension is
finite the massive modes are plane-wave normalizable, while the zero mode is
quadratically normalizable. We then discuss the coupling of domain wall gravity
to localized 4-dimensional matter. In particular, we point out that this
coupling is consistent only if the matter is conformal. This is different from
the Randall-Sundrum case as there is a discontinuity in the delta-function-like
limit of such a smooth domain wall - the latter breaks diffeomorphisms only
spontaneously, while the Randall-Sundrum brane breaks diffeomorphisms
explicitly. Finally, at the quantum level both the domain wall as well as the
Randall-Sundrum setups suffer from inconsistencies in the coupling between
gravity and localized matter, as well as the fact that gravity is generically
expected to be delocalized in such backgrounds due to higher curvature terms.

</DOC>
<DOC>
<DOCNO> 170181 </DOCNO>
Locality and Bell's inequality


  We prove that the locality condition is irrelevant to Bell in equality. We
check that the real origin of the Bell's inequality is the assumption of
applicability of classical (Kolmogorovian) probability theory to quantum
mechanics. We describe the chameleon effect which allows to construct an
experiment realizing a local, realistic, classical, deterministic and
macroscopic violation of the Bell inequalities.

</DOC>
<DOC>
<DOCNO> 67877 </DOCNO>
P-Parity Violating Bound States of Particles with Anomalous Magnetic


  We consider bound states of fermions with an anomalous magnetic
moments(neutrinos,neutrons) in radial electric and magnetic field of
monopole.In case of radial magnetic field the interaction $\vec{\Sigma}\vec{H}$
violates P-parity and for this reason we must use the method of
(hep-ph/9901248) where both components of spinor considererd as a linear
combination of spheric spinors with different P-parity. Also we apply
pseudoscalar-like interaction (2) obtained in \cite{DF} to monopole case and
add it in Dirac equation.We obtain the system of differential equations for
radial functions which define energy levels of fermions with anomalous magnetic
moments in the presence of monopole.

</DOC>
<DOC>
<DOCNO> 151120 </DOCNO>
What Do We Learn about Confinement from the Seiberg-Witten Theory


  The confinement scenario in N=2 supersymmetric gauge theory at the monopole
point is reviewed. Basic features of this U(1) confinement are contrasted with
those we expect in QCD. In particular, extra states in the hadron spectrum and
non-linear Regge trajectories are discussed. Then another confinement scenario
arising on Higgs branches of the theory with fundamental matter is also
reviewed. Peculiar properties of the Abrikosov-Nielsen-Olesen string on the
Higgs branch lead to a new confining regime with the logarithmic suppression of
the linear rising potential. Motivations for a search for tensionless strings
are proposed.

</DOC>
<DOC>
<DOCNO> 100387 </DOCNO>
Simultaneous approximation and interpolation of functions on continua in


  We construct polynomial approximations of Dzjadyk type (in terms of the k-th
modulus of continuity, $k \ge 1$) for analytic functions defined on a continuum
E in the complex plane, which simultaneously interpolate at given points of E.
Furthermore, the error in this approximation is decaying as $e^{-cn^\alpha}$
strictly inside E, where c and $\alpha$ are positive constants independent of
the degree n of the approximating polynomial.

</DOC>
<DOC>
<DOCNO> 170350 </DOCNO>
Quantum Optical Discussion of Uncertainty and Complementarity in a


  We discuss complementarity and uncertainty in a gedanken Which-Way
(Welcher-Weg) experiment in a Mach-Zehnder interferometer. Although a
Welcher-Weg measurement can be performed with only a negligible amount of
momentum change in the detector itself, the change in the interference pattern
must correspond to a change in the momentum distribution of the particle.
Entanglement between the Mach-Zehnder interferometer and the Welcher-Weg
measurement introduces orthogonality that disables the interference of the
particle, but simultaneously, it also generates a momentum transfer between the
particle and other parts of the whole entangled system (including macroscopic
parts). This analysis can be related to the Delayed Choice interpretation. We
show where the momentum change takes place and we conclude that entanglement is
the key to understand how complementarity (i.e. Which Way versus interference)
and the position-momentum uncertainty relation are interwoven.

</DOC>
<DOC>
<DOCNO> 10024 </DOCNO>
Voltage and temperature dependence of the grain boundary tunneling


  We have performed a systematic analysis of the voltage and temperature
dependence of the tunneling magnetoresistance (TMR) of grain boundaries (GB) in
the manganites. We find a strong decrease of the TMR with increasing voltage
and temperature. The decrease of the TMR with increasing voltage scales with an
increase of the inelastic tunneling current due to multi-step inelastic
tunneling via localized defect states in the tunneling barrier. This behavior
can be described within a three-current model for magnetic tunnel junctions
that extends the two-current Julliere model by adding an inelastic,
spin-independent tunneling contribution. Our analysis gives strong evidence
that the observed drastic decrease of the GB-TMR in manganites is caused by an
imperfect tunneling barrier.

</DOC>
<DOC>
<DOCNO> 102330 </DOCNO>
Restricted single or double signed patterns


  Let $E_n^r=\{[\tau]_a=(\tau_1^{(a_1)},...,\tau_n^{(a_n)})| \tau\in S_n,\
1\leq a_i\leq r\}$ be the set of all signed permutations on the symbols
1,2,...,n with signs 1,2,...,r. We prove, for every 2-letter signed pattern
$[\tau]_a$, that the number of $[\tau]_a$-avoiding signed permutations in
$E_n^r$ is given by the formula $\sum\limits_{j=0}^n j!(r-1)^j{n\choose j}^2$.
Also we prove that there are only one Wilf class for r=1, four Wilf classes for
r=2, and six Wilf classes for $r\geq 3$.

</DOC>
<DOC>
<DOCNO> 151797 </DOCNO>
Multi-Instanton Calculus in Supersymmetric Theories


  In this talk I review some recent results concerning multi-instanton calculus
in supersymmetric field theories. More in detail, I will show how these
computations can be efficiently performed using the formalism of topological
field theories.

</DOC>
<DOC>
<DOCNO> 10699 </DOCNO>
Pauli principle and Green's function formalism


  The Green's function formalism in Condensed Matter Physics is revisited
within the equation of motion approach. The two-time retarded (advanced) and
causal Green's functions carry substantially different information. Green's
function expressions, dispersion relations and sum rules that take into account
the presence of the zero-frequency constants are derived. We show how is
possible to properly compute both unknown parameters and zero-frequency
components of Green's functions (i.e., to unambiguously fix the representation
of the Hilbert space) by means of the Pauli principle. To illustrate this
procedure some examples are given: the complete solution of the two-site
Hubbard model, the evaluation of spin and charge correlators for a narrow-band
Bloch system and a study of the spin dynamics in the Double-Exchange model.

</DOC>
<DOC>
<DOCNO> 39823 </DOCNO>
Measurement of Azimuthal Asymmetries in Deep Inelastic Scattering


  The distribution of the azimuthal angle for the charged hadrons has been
studied in the hadronic centre-of-mass system for neutral current deep
inelastic positron-proton scattering with the ZEUS detector at HERA.
Measurements of the dependence of the moments of this distribution on the
transverse momenta of the charged hadrons are presented. Asymmetries that can
be unambiguously attributed to perturbative QCD processes have been observed
for the first time.

</DOC>
<DOC>
<DOCNO> 71210 </DOCNO>
Charged Lepton Flavour Violation from Massive Neutrinos in Z Decays


  Present evidences for neutrino masses and lepton flavour mixings allow to
predict, in the Standard Model with light neutrinos, branching rates for the
decays Z --> e mu, mu tau, e tau of less than 10^{-54}, while present
experimental exclusion limits from LEP 1 are of order 10^{-5}. The GigaZ option
of the TESLA Linear Collider project will extend the sensitivity down to about
10^{-8}. We study in a systematic way some minimal extensions of the Standard
Model and show that GigaZ might well be sensitive to the rates predicted from
these scenarios.

</DOC>
<DOC>
<DOCNO> 85391 </DOCNO>
Mixmaster chaos


  The significant discussion about the possible chaotic behavior of the
mixmaster cosmological model due to Cornish and Levin [J.N. Cornish and J.J.
Levin, Phys. Rev. Lett. 78 (1997) 998; Phys. Rev. D 55 (1997) 7489] is
revisited. We improve their method by correcting nontrivial oversights that
make their work inconclusive to precisely confirm their result: ``The mixmaster
universe is indeed chaotic''.

</DOC>
<DOC>
<DOCNO> 70486 </DOCNO>
The g Factor of a Bound Electron in a Hydrogen-Like Atom


  Recently, a precise measurement on the bound electron g factor in
hydrogen-like carbon was performed [1]. We consider the present status of the
theory of the g factor of an electron bound in a hydrogen-like atom and discuss
new opportunities and possible applications of the recent experiment.

</DOC>
<DOC>
<DOCNO> 12252 </DOCNO>
Characteristic length scales and formation of vortices in the Abelian


  In this brief report we consider a non-local Abelian Higgs model in the
presence of a neutralizing uniform background charge. We show that such a
system possesses vortices which key feature is a strong radial electric field.
We estimate the basic properties of such an object and characteristic length
scales in this model.

</DOC>
<DOC>
<DOCNO> 72130 </DOCNO>
Neutrino mass and oscillation as probes of physics beyond the Standard


  We present a review of the present status of the problem of neutrino masses
and mixing including a survey of theoretical motivations and models,
experimental searches and implications of recently appeared solar and
atmospheric neutrino data, which strongly indicate nonzero neutrino masses and
mixing angles.

</DOC>
<DOC>
<DOCNO> 118297 </DOCNO>
Snapshot coronagraphy with an interferometer in space


  Diluted arrays of many optical apertures will be able to provide h
igh-resolution snapshot images if the beams are combined according to the
densified-pupil scheme. We show that the same principle can also provide
coronagraphic images, for detecting faint sources near a bright unresolved one.
Recent refinements of coronagraphic techniques, i.e. the use of a phase mask,
active apodization and dark-speckle analysis, are also applicable for enhanced
contrast. Implemented in the form of a proposed 50-500m Exo-Earth Discoverer
array in space, the principle can serve to detect Earth-like exo-planets in the
infra-red. It can also provide images of faint nebulosity near stars, active
galactic nuclei and quasars. Calculations indicate that exo-planets are
detectable amidst the zodiacal and exo-zodiacal emission faster than with a
Bracewell array of equivalent area, a consequence of the spatial selectivity in
the image.

</DOC>
<DOC>
<DOCNO> 152179 </DOCNO>
The Supersymmetric Kink via Higher-Derivative and Momentum Cut-Off


  We study the supersymmetric kink with higher derivative and momentum cut-off
regularization schemes. We introduce the new momentum cut-off regularization
scheme which we call ``generalized momentum cut-off''. A new, explicit
computation for the central charge anomaly for this scheme is described in
detail. The calculation of the first order mass corrections for the bosonic and
supersymmetric kink within the momentum cut-off is presented in hep-th/0010051,
so that one can compare the one-loop central charge and mass computed
independently within the same regularization setup. We confirm that the BPS
bound is saturated in one loop level. Thus the Wilsonian momentum cut-off
regularization scheme is rehabilitated as a bona fide procedure for computing
quantum corrections in the topologically nontrivial backgrounds. We lead the
reader to the idea that a consistent regularization in general does not only
assume that one regulates loops properly, but also requires caution in defining
the total number of modes involved in the quantization of the theory. We also
study the higher-derivative regularization scheme of Shifman et al. in great
detail. We extend the Noether method for the case when the higher-derivatives
are present in the Lagrangian. The extensive discussion of the technical
aspects and the consistency of the higher-derivative scheme is given. We show
that higher-derivative regularization gives, in general, a nonlocal topological
current, which leads to the correct value of the anomaly in the central charge.
We also comment on the status of the dimensional regularization approach to the
computation of the central charge anomaly and kink mass.

</DOC>
<DOC>
<DOCNO> 7982 </DOCNO>
Independent Ion Migration in Suspensions of Strongly Interacting Charged


  We report on sytematic measurements of the low frequency conductivity in
aequous supensions of highly charged colloidal spheres. System preparation in a
closed tubing system results in precisely controlled number densities between
1E16/m3 and 1E19/m^3 (packing fractions between 1E-7 and 1E-2) and electrolyte
concentrations between 1E-7 and 1E-3 mol/l. Due to long ranged Coulomb
repulsion some of the systems show a pronounced fluid or crystalline order.
Under deionized conditions we find s to depend linearily on the packing
fraction with no detectable influence of the phase transitions. Further at
constant packing fraction s increases sublinearily with increasing number of
dissociable surface groups N. As a function of c the conductivity shows
pronounced differences depending on the kind of electrolyte used. We propose a
simple yet powerful model based on independent migration of all species present
and additivity of the respective conductivity contributions. It takes account
of small ion macro-ion interactions in terms of an effectivly transported
charge. The model successfully describes our qualitatively complex experimental
observations. It further facilitates quantitative estimates of conductivity
over a wide range of particle and experimental parameters.

</DOC>
<DOC>
<DOCNO> 70604 </DOCNO>
Summary of Neutrino 2000


  Aspects of neutrino physics beyond the Standard Model are emphasized,
including the emerging default options for atmospheric and solar neutrino
oscillations, namely nu_mu to nu_tau and nu_e to nu_{mu,tau} respectively, and
the need to check them, the prospects opened up by the successful starts of SNO
and K2K, the opportunities for future long-baseline neutrino experiments and
high-energy astrophysical neutrinos. Finally, comments are made on the road map
for realizing the exciting physics potential of neutrino factories.

</DOC>
<DOC>
<DOCNO> 71996 </DOCNO>
Lifetimes of b-flavoured hadrons


  I discuss the heavy quark expansion for the inclusive widths of heavy-light
hadrons, which predicts quite well the experimental ratios of B_q meson
lifetimes. As for $\Lambda_b$, current determinations of ${\cal O}(m_b^{-3})$
contribution to $\tau(\Lambda_b)$ do not allow to explain the small measured
value of $\tau(\Lambda_b)/\tau(B_d)$. As a final topic, I discuss the
implications of the measurement of the B_c lifetime.

</DOC>
<DOC>
<DOCNO> 101000 </DOCNO>
Lusternik--Schnirelmann theory on general spaces


  We extend Lusternik-Schnirelmann theory to pairs $(f, \phi)$, where $\phi$ is
a homotopy equivalence of a space $X$, $f$ is a function on $X$ which decreases
along $\phi$ and $(f, \phi)$ satisfies a discrete analog of the Palais-Smale
condition. The theory is carried out in an equivariant setting.

</DOC>
<DOC>
<DOCNO> 170787 </DOCNO>
Entropy and information gain in quantum continual measurements


  The theory of measurements continuous in time in quantum mechanics (quantum
continual measurements) has been formulated by using the notions of instrument,
positive operator valued measure, etc., by using quantum stochastic
differential equations and by using classical stochastic differential equations
(SDE's) for vectors in Hilbert spaces or for trace-class operators. In the same
times Ozawa made developments in the theory of instruments and introduced the
related notions of a posteriori states and of information gain [1].
  In this paper we introduce a simple class of SDE's relevant to the theory of
continual measurements and we recall how they are related to instruments and a
posteriori states and, so, to the general formulation of quantum mechanics.
Then we introduce and use the notion of information gain and the other results
of the paper [1] inside the theory of continual measurements.
  [1] M. Ozawa, On information gain by quantum measurements of continuous
observables, J. Math. Phys. 27 (1986) 759-763.

</DOC>
<DOC>
<DOCNO> 170044 </DOCNO>
Direct sampling of exponential phase moments of smoothed Wigner


  We investigate exponential phase moments of the s-parametrized
quasidistributions (smoothed Wigner functions). We show that the knowledge of
these moments as functions of s provides, together with photon-number
statistics, a complete description of the quantum state. We demonstrate that
the exponential phase moments can be directly sampled from the data recorded in
balanced homodyne detection and we present simple expressions for the sampling
kernels. The phase moments are Fourier coefficients of phase distributions
obtained from the quasidistributions via integration over the radial variable
in polar coordinates. We performed Monte Carlo simulations of the homodyne
detection and we demonstrate the feasibility of direct sampling of the moments
and subsequent reconstruction of the phase distribution.

</DOC>
<DOC>
<DOCNO> 118597 </DOCNO>
Nearly Coherent Oscillations in Type I X-Ray Bursts from KS 1731-260


  We present an analysis of the nine type I X-ray bursts that were observed
from KS 1731-260 with RXTE. We find that the bursts divide naturally into two
populations: ``fast bursts'' occur on the Banana Branch when the accretion rate
is high and exhibit short decay times, high peak fluxes, and radius expansion
episodes. ``Slow bursts'' occur in the Island State at lower accretion rates,
have lower peak fluxes, higher fluences, longer decay times, and show no
evidence of radius expansion. All five of the fast bursts, and none of the four
slow bursts, show coherent oscillations near 524 Hz.
  We perform in-burst phase connection of the burst pulsations, which allows us
to unambiguously characterize their frequency evolution. That evolution
exhibits a variety of behaviors, including a sharp spin-down during one burst.
Applying our phase models, we find that the pulsations are spectrally harder
than the burst emission, with the strength of the pulsations increasing
monotonically with photon energy. Coherently summing all of the burst signals,
we find upper limits of ~5% relative to the strength of the main pulse on any
modulation at 1/2 or 3/2 the main pulse frequency. We discuss our results in
the context of models in which the burst pulsations are produced by a hot spot
on the surface of a spinning neutron star.

</DOC>
<DOC>
<DOCNO> 84668 </DOCNO>
Space-times admitting a three-dimensional conformal group


  Perfect fluid space-times admitting a three-dimensional Lie group of
conformal motions containing a two-dimensional Abelian Lie subgroup of
isometries are studied. Demanding that the conformal Killing vector be proper
(i.e., not homothetic nor Killing), all such space-times are classified
according to the structure of their corresponding three-dimensional conformal
Lie group and the nature of their corresponding orbits (that are assumed to be
non-null). Each metric is then explicitly displayed in coordinates adapted to
the symmetry vectors. Attention is then restricted to the diagonal case, and
exact perfect fluid solutions are obtained in both the cases in which the fluid
four-velocity is tangential or orthogonal to the conformal orbits, as well as
in the more general "tilting" case.

</DOC>
<DOC>
<DOCNO> 71638 </DOCNO>
Single Spin Asymmetries in Semi-Inclusive Electroproduction: Access to


  We discuss the quark transversity distribution function and a possible way to
access it through the measurement of single spin azimuthal asymmetry in
semi-inclusive single pion electroproduction on a transversely polarized
target.

</DOC>
<DOC>
<DOCNO> 67691 </DOCNO>
The deconfinement phase transition, hadronization and the NJL model


  One of the confident predictions of QCD is that at sufficiently high
temperature and/or density, hadronic matter should undergo a thermodynamic
phase transition to a colour deconfined state of matter - popularly called the
Quark-Gluon Plasma (QGP). In low energy effective theories of Quantum
Chromodynamics (QCD), one usually talks of the chiral transition for which a
well defined order parameter exists. We investigate the dissociation of pions
and kaons in a medium of hot quark matter decsribed by the Nambu - Jona Lasinio
(NJL) model. The decay widths of pion and kaon are found to be large but finite
at temperature much higher than the critical temperature for the chiral (or
deconfinement) transition, the kaon decay width being much larger. Thus pions
and even kaons (with a lower density compared to pions) may coexist with quarks
and gluons at such high temperatures. On the basis of such premises, we
investigate the process of hadronization in quark-gluon plasma with special
emphasis on whether such processes shed any light on acceptable low energy
effective theories of QCD.

</DOC>
<DOC>
<DOCNO> 11941 </DOCNO>
Order-disorder transition in nanoscopic semiconductor quantum rings


  Using the path integral Monte Carlo technique we show that semiconductor
quantum rings with up to six electrons exhibit a temperature, ring diameter,
and particle number dependent transition between spin ordered and disordered
Wigner crystals. Due to the small number of particles the transition extends
over a broad temperature range and is clearly identifiable from the electron
pair correlation functions.

</DOC>
<DOC>
<DOCNO> 8237 </DOCNO>
Algebraic equivalence between certain models for superfluid--insulator


  Algebraic contraction is proposed to realize mappings between models
Hamiltonians. This transformation contracts the algebra of the degrees of
freedom underlying the Hamiltonian. The rigorous mapping between the
anisotropic $XXZ$ Heisenberg model, the Quantum Phase Model, and the Bose
Hubbard Model is established as the contractions of the algebra $u(2)$
underlying the dynamics of the $XXZ$ Heisenberg model.

</DOC>
<DOC>
<DOCNO> 69270 </DOCNO>
There is no $\kappa(900)$


  In the I=0 sector there are more scalar mesons than can fit in one $q{\bar
q}$ nonet. Consequently, many have claimed that there is in fact more than one
multiplet, perhaps both $q{\bar q}$ and $qq{\bar {qq}}$. Such proposals require
the existence of at least two strange isodoublets (and their antiparticles).
The current PDG Tables list just one state, the $K^*_0(1430)$, while fits to
data with Breit-Wigner forms and variable backgrounds can accommodate a
$\kappa(900)$ too. Whether a state exists in the spectrum of hadrons is not a
matter of ability to fit data along the real energy axis, but is completely
specified by the number of poles in the complex energy plane. Here we perform a
model-independent analytic continuation of $\pi K$ scattering results between
825 MeV and 2 GeV to determine the number and position of resonance poles. We
find that there {\bf is} a $K^*_0(1430)$, but {\bf no} $\kappa(900)$. The LASS
data cannot rule out the possibility of a very low mass $\kappa$ well below 825
MeV.

</DOC>
<DOC>
<DOCNO> 99666 </DOCNO>
Classical and quantum info-manifolds


  We survey recent work on the Cramer-Rao inequality by Hasagawa and Petz; the
notion of information manifold in infinite-dimensional Hilbert spaces is
introduced, and the extension by Grasselli and the author to quadratic form
perturbations is summarised.

</DOC>
<DOC>
<DOCNO> 68636 </DOCNO>
Order (alpha^2 Gamma, alpha^3 Gamma) Binding Effects in Orthopositronium


  We present a new, simplified analysis of the low-energy electron-positron
interaction, and use the resulting effective theory to calculate the binding
effects that contribute to the decay rate, Gamma, of orthopositronium, through
Order(alpha^3 ln(alpha) Gamma). We express the total decay rate in terms of the
annihilation rate for a free electron and positron at threshold, which has just
recently been computed to sufficient precision. Our result corrects errors in a
previous analysis.

</DOC>
<DOC>
<DOCNO> 118155 </DOCNO>
Simultaneous Measurements of X-Ray Luminosity and Kilohertz


  We measure simultaneously the properties of the energy spectra and the
frequencies of the kilohertz quasi-periodic oscillations (QPOs) in fifteen low
mass X-ray binaries covering a wide range of X-ray luminosities. In each source
the QPO frequencies cover the same range of approximately 300 Hz to 1300 Hz,
though the sources differ by two orders of magnitude in their X-ray
luminosities (as measured from the unabsorbed 2-50 keV flux). So the X-ray
luminosity does not uniquely determine the QPO frequency. This is difficult to
understand since the evidence from individual sources indicates that the
frequency and luminosity are very well correlated at least over short
timescales. Perhaps beaming effects or bolometric corrections change the
observed luminosities, or perhaps part of the energy in mass accretion is used
to power outflows reducing the energy emitted in X-rays. It is also possible
that the parameters of a QPO model are tuned in such a way that the same range
of frequencies appears in all sources. Different modes of accretion may be
involved for example (disk and radial) or multiple parameters may conspire to
yield the same frequencies.

</DOC>
<DOC>
<DOCNO> 117325 </DOCNO>
An interpolation model for the equation of state in binary systems


  The new interpolation model of state of binary mixture is investigated. This
model use only two parameters and produce many type of phase diagrams.

</DOC>
<DOC>
<DOCNO> 117705 </DOCNO>
Cross-correlating the Sloan Digital Sky Survey with the Microwave Sky


  While most of the microwave background fluctuations on angular scales greater
than a few arcminutes were generated at z > 800, the low redshift universe does
distort the microwave background. Since the Sloan Digital Sky Survey (SDSS)
traces the structures in the low-redshift universe, we can gain additional
insights into the physics of the low-redshift universe by cross-correlating
microwave background maps with template maps produced from the SDSS. We present
a formalism for cross-correlating data from the Microwave Anisotropy Probe
(MAP) with the Sloan Survey for the thermal Sunyaev-Zel'dovich (SZ) effect, the
Integrated Sachs-Wolfe (ISW) effect, and weak lensing. This formalism is used
to compute the signal-to-noise for cross-correlating these effects with various
classes of tracer objects from the SDSS. It is found that the anticipated
samples of SDSS quasars and galaxies with photometrically-determined redshifts
would be good tracers for cross-correlating with the CMB. We find that the
SZ-galaxy cross-correlation would give good constraints on pressure
fluctuations in supercluster-scale gas. Cross-correlating weakly-lensed quasars
with maps of the convergence of the CMB is found to give strong constraints on
Omega_0 as well as the equation of state w. We find that the ISW
cross-correlation gives poor signal-to-noise using these techniques.

</DOC>
<DOC>
<DOCNO> 84568 </DOCNO>
Approximate equation relevant to axial oscillations on slowly rotating


  Axial oscillations relevant to the r-mode instability are studied with slow
rotation formalism in general relativity. The approximate equation governing
the oscillations is derived with second-order rotational corrections. The
equation contains an effective 'viscosity-like' term, which originates from
coupling to the polar g-mode displacements. The term plays a crucial role on
the resonance point, where the disturbance on the rotating stars satisfies a
certain condition at the lowest order equation. The effect is significant for
newly born hot neutron stars, which are expected to be subject to the
gravitational radiation driven instability of the r-mode.

</DOC>
<DOC>
<DOCNO> 122361 </DOCNO>
Nuclear obscuration and scattering in Seyfert 2 galaxies


  We study the relation between gaseous absorbing column density (N$_{\rm H}$),
infrared colors and detectability of the broad lines in a large sample of
Seyfert 2 galaxies(Sy2s). We confirm that Sy2s without polarized broad lines
tend to have cooler 60$\mu$m/25$\mu$m colors; this correlation was previously
ascribed to the effect of obscuration towards the nuclear region.
  We find some evidence that Sy2s without polarized broad lines have larger
absorbing column density (N$_{\rm H}$) and that a fraction of them are
characterized by dust lanes crossing their nuclei.
  However, we find that the IR colors do not correlate with N$_{\rm H}$, in
disagreement with the obscuration scenario.
  Also, Sy2s without polarized broad lines follow the same radio-FIR relation
as normal and starburst galaxies, at variance with Sy2s with polarized broad
lines. These results indicate that the lack of broad lines in the polarized
spectrum of Sy2s is mostly due to the contribution/dilution from the host
galaxy or from a circumnuclear starburst, though at a lower extent the
obscuration toward the nuclear region also plays a role.

</DOC>
<DOC>
<DOCNO> 116410 </DOCNO>
Radiation from a Superluminal Source


  The sweep speed of an electron beam across the face of an oscilloscope can
exceed the velocity of light, although of course the velocity of the electrons
does not. Associated with this possibility there should be a kind of Cherenkov
radiation, as if the oscilloscope trace were due to a charge moving with
superluminal velocity.

</DOC>
<DOC>
<DOCNO> 100352 </DOCNO>
Group Theoretical Quantization of Phase and Modulus Related to


  Following a recent group theoretical quantization of the symplectic space
S={(phi in R mod 2pi, p>0)} in terms of irreducible unitary representations of
the group SO(1,2) the present paper proposes an application of those results to
the old problem of quantizing modulus and phase in interference phenomena: The
self-adjoint Lie algebra generators K_1, K_2 and K_3 of that group correspond
to the classical observables p cos(phi), -p sin(phi) and p > 0 the Poisson
brackets of which obey that Lie algebra, too. For the irreducible unitary
representations of the positive series the modulus operator K_3 has the
positive discrete spectrum {n+k, n=0,1,2,...; k > 0}. Self-adjoint operators
for cos(phi) and sin(phi) can then be defined as (K_3^{-1}K_1 + K_1 K_3^{-1})/2
and - (K_3^{-1} K_2 + K_2 K_3^{-1})/2 which have the theoretically desired
properties for k >0.32. Some matrix elements with respect to number eigenstates
and with respect to coherent states are calculated. One conclusion is that
group theoretical quantization may be tested by quantum optical experiments.

</DOC>
<DOC>
<DOCNO> 151787 </DOCNO>
Will the Real 4D, N=1 SG Limit of Superstring/M-Theory Please Stand Up?


  At the component-level we study the `beta-function-favored constraint' (bffc)
formalism, suggested in 1988 as the most natural formulation for supergravity
derived from more fundamental theories. We begin with the suggestion that \bffc
supergravity be identified with new minimal supergravity together with an
additional chiral compensator multiplet. After $U_{\rm A}(1)$symmetry breaking,
the non-propagating axion 2-form of new minimal supergravity becomes the
propagating axion 2-form required by string theory. The final form of the
theory is seen to uniquely allow four simultaneous features: (i) local
supersymmetry, (ii) implementation of the Green-Schwarz mechanism, (iii) a
supersymmetry-breaking order parameter chiral superfield, and (iv) a dilaton
superpotential.

</DOC>
<DOC>
<DOCNO> 100101 </DOCNO>
Fedosov Deformation Quantization as a BRST Theory


  The relationship is established between the Fedosov deformation quantization
of a general symplectic manifold and the BFV-BRST quantization of constrained
dynamical systems. The original symplectic manifold $\mathcal M$ is presented
as a second class constrained surface in the fibre bundle ${{\mathcal
T}^*_\rho}{\mathcal M}$ which is a certain modification of a usual cotangent
bundle equipped with a natural symplectic structure. The second class system is
converted into the first class one by continuation of the constraints into the
extended manifold, being a direct sum of ${{\mathcal T}^*_\rho}{\mathcal M}$
and the tangent bundle $T {\mathcal M}$. This extended manifold is equipped
with a nontrivial Poisson bracket which naturally involves two basic
ingredients of Fedosov geometry: the symplectic structure and the symplectic
connection. The constructed first class constrained theory, being equivalent to
the original symplectic manifold, is quantized through the BFV-BRST procedure.
The existence theorem is proven for the quantum BRST charge and the quantum
BRST invariant observables. The adjoint action of the quantum BRST charge is
identified with the Abelian Fedosov connection while any observable, being
proven to be a unique BRST invariant continuation for the values defined in the
original symplectic manifold, is identified with the Fedosov flat section of
the Weyl bundle. The Fedosov fibrewise star multiplication is thus recognized
as a conventional product of the quantum BRST invariant observables.

</DOC>
<DOC>
<DOCNO> 116345 </DOCNO>
Josephson effects in dilute Bose-Einstein condensates


  We propose an experiment that would demonstrate the ``dc'' and ``ac''
Josephson effects in two weakly linked Bose-Einstein condensates. We consider a
time-dependent barrier, moving adiabatically across the trapping potential. The
phase dynamics are governed by a ``driven-pendulum'' equation, as in
current-driven superconducting Josephson junctions. At a critical velocity of
the barrier (proportional to the critical tunneling current), there is a sharp
transition between the ``dc'' and ``ac'' regimes. The signature is a sudden
jump of a large fraction of the relative condensate population. Analytical
predictions are compared with a full numerical solution of the time dependent
Gross-Pitaevskii equation, in an experimentally realistic situation.

</DOC>
<DOC>
<DOCNO> 83301 </DOCNO>
Two Steps Feature Selection and Neural Network Classification for the


  For the TREC-8 routing, one specific filter is built for each topic. Each
filter is a classifier trained to recognize the documents that are relevant to
the topic. When presented with a document, each classifier estimates the
probability for the document to be relevant to the topic for which it has been
trained. Since the procedure for building a filter is topic-independent, the
system is fully automatic.
  By making use of a sample of documents that have previously been evaluated as
relevant or not relevant to a particular topic, a term selection is performed,
and a neural network is trained. Each document is represented by a vector of
frequencies of a list of selected terms. This list depends on the topic to be
filtered; it is constructed in two steps. The first step defines the
characteristic words used in the relevant documents of the corpus; the second
one chooses, among the previous list, the most discriminant ones. The length of
the vector is optimized automatically for each topic. At the end of the term
selection, a vector of typically 25 words is defined for the topic, so that
each document which has to be processed is represented by a vector of term
frequencies.
  This vector is subsequently input to a classifier that is trained from the
same sample. After training, the classifier estimates for each document of a
test set its probability of being relevant; for submission to TREC, the top
1000 documents are ranked in order of decreasing relevance.

</DOC>
<DOC>
<DOCNO> 102511 </DOCNO>
Duality and Rational Modules in Hopf Algebras over Commutative Rings


  Let $A$ be an algebra over a commutative ring $R$. If $R$ is noetherian and
$A^\circ$ is pure in $R^A$, then the categories of rational left $A$-modules
and right $A^\circ$-comodules are isomorphic. In the Hopf algebra case, we can
also strengthen the Blattner-Montgomery duality theorem. Finally, we give
sufficient conditions to get the purity of $A^\circ$ in $R^A$.

</DOC>
<DOC>
<DOCNO> 169789 </DOCNO>
Entanglement and Collective Quantum Operations


  We show how shared entanglement, together with classical communication and
local quantum operations, can be used to perform an arbitrary collective
quantum operation upon N spatially-separated qubits. A simple
teleportation-based protocol for achieving this, which requires 2(N-1) ebits of
shared, bipartite entanglement and 4(N-1) classical bits, is proposed. In terms
of the total required entanglement, this protocol is shown to be optimal for
even N in both the asymptotic limit and for `one-shot' applications.

</DOC>
<DOC>
<DOCNO> 152351 </DOCNO>
Topological Unconstrained QCD


  "Equivalent unconstrained systems" for QCD obtained by resolving the Gauss
law are discussed. We show that the effects of hadronization, confinement,
spontaneous chiral symmetry breaking and $\eta_0$-meson mass can be hidden in
solutions of the non-Abelian Gauss constraint in the class of functions of
topological gauge transformations, in the form of a monopole, a zero mode of
the Gauss law, and a rising potential.

</DOC>
<DOC>
<DOCNO> 100466 </DOCNO>
Estimates of Weil-Petersson volumes via effective divisors


  We study the asymptotics of the Weil-Petersson volumes of the moduli spaces
of compact Riemann surfaces of genus $g$ with $n$ punctures, for fixed $n$ as
$g \to \infty$.

</DOC>
<DOC>
<DOCNO> 100734 </DOCNO>
Analytic continuation and resonance-free regions for Sturm-Liouville


  We are concerned with the Sturm-Liouville problem on the half line. We show
that when the potential $q$ is subject only to power decay at infinity the
$L^2$ solution may be continued into a sector of the so-called un-physical
sheet. This gives rise to resonance free regions and the numerical estimation
of resonances outside these regions.

</DOC>
<DOC>
<DOCNO> 151524 </DOCNO>
Reminiscences of Collaborations with Joel Scherk


  I had the privilege of collaborating with Joel Scherk on three separate
occasions: in 1970 at Princeton, in 1974 at Caltech, and in 1978-79 at the
Ecole Normale Superieure. In this talk I give some reminiscences of these
collaborations.

</DOC>
<DOC>
<DOCNO> 121365 </DOCNO>
Stellar dynamics observations of a double nucleus in M 83


  We report on the discovery of a double nucleus in M 83, based on measurements
of the line of sight velocity distribution of stars observed at near infrared
wavelengths with the VLT ISAAC spectrograph. We observe two peaks separated by
2.7" in the velocity dispersion profile of light from late-type stars measured
along a slit 0.6" wide, centered on the peak of K band emission and with P.A.
51.7 degrees. The first peak coincides with the peak of the K band light
distribution, widely assumed to be the galaxy nucleus. The second peak, of
almost equal strength, almost coincides with the center of symmetry of the
outer isophotes of the galaxy. The secondary peak location has little K band
emission, and appears to be significantly extincted, even at near infrared
wavelengths. It also lies along a mid-infrared bar, previously identified by
Gallais et al. (1991) and shows strong hydrogen recombination emission at 1.875
microns. If we interpret the observed stellar velocity dispersion as coming
from a virialized system, the two nuclei would each contain an enclosed mass of
13.2 x 10^6 M_sun within a radius of 5.4pc. These could either be massive star
clusters, or supermassive dark objects.

</DOC>
<DOC>
<DOCNO> 102844 </DOCNO>
Q-power function over Q-commuting variables and deformed XXX, XXZ chains


  We find certain functional identities for the Gauss q-power function of a sum
of q-commuting variables. Then we use these identities to obtain two-parameter
twists of the quantum affine algebra U_q (\hat{sl}_2) and of the Yangian
Y(sl_2). We determine the corresponding deformed trigonometric and rational
quantum R-matrices, which then are used in the computation of deformed XXX and
XXZ Hamiltonians.

</DOC>
<DOC>
<DOCNO> 69215 </DOCNO>
Flavour Violation in SUSY SU(5) GUT at Large tan beta


  We study flavour violation in the minimal SUSY SU(5) GUT assuming all the
third generation Yukawa couplings to be due to the renormalizable physics above
GUT scale. At large $\tan\beta,$ as suggested by Yukawa unification in SU(5),
sizable flavour violation in the left (right) slepton (down squark) sector is
induced due to renormalization effects of down type Yukawa couplings between
GUT and Planck scales in addition to the flavour violation in the right slepton
sector. The new flavour physics contribution to $K-\bar K,$ $B-\bar B$ mixing
is small but might be of phenomenological interest in the case of $b\to
s\gamma.$ The sign of the latter contribution is the same as the sign of the
dominant chargino contribution, thus making the constraints on SUSY scale
coming from $b\to s\gamma$ somewhat more restrictive. The most important
feature of the considered scenario is the large rate of lepton flavour
violation. Given the present experimental constraints, the $\mu\to e\gamma$ and
$\mu-e$ conversion branching ratios are above the sensitivity of the planned
experiments unless the SUSY scale is pushed above one TeV.

</DOC>
<DOC>
<DOCNO> 116393 </DOCNO>
Are the Laws of Thermodynamics Consequences of a Fractal Properties of


  Why in our Universe the laws of thermodynamics are valid? In the paper is
demonstrated the reason of it: if the time and the space are multifractal and
the Universe is in an equilibrium state the laws of the thermodynamics are
consequences of it's multifractal structure.

</DOC>
<DOC>
<DOCNO> 83207 </DOCNO>
A Denotational Semantics for First-Order Logic


  In Apt and Bezem [AB99] (see cs.LO/9811017) we provided a computational
interpretation of first-order formulas over arbitrary interpretations. Here we
complement this work by introducing a denotational semantics for first-order
logic. Additionally, by allowing an assignment of a non-ground term to a
variable we introduce in this framework logical variables.
  The semantics combines a number of well-known ideas from the areas of
semantics of imperative programming languages and logic programming. In the
resulting computational view conjunction corresponds to sequential composition,
disjunction to ``don't know'' nondeterminism, existential quantification to
declaration of a local variable, and negation to the ``negation as finite
failure'' rule. The soundness result shows correctness of the semantics with
respect to the notion of truth. The proof resembles in some aspects the proof
of the soundness of the SLDNF-resolution.

</DOC>
<DOC>
<DOCNO> 100420 </DOCNO>
Partial measures


  We study sigma-additive set functions defined on a hereditary subclass of a
sigma-algebra and taken values in the extended real line. Analogs of the Jordan
decomposition theorem and the Radon-Nikodym theorem are obtained.

</DOC>
<DOC>
<DOCNO> 84575 </DOCNO>
Notes on causal differencing in ADM/CADM formulations: a 1D comparison


  Causal differencing has shown to be one of the promising and successful
approaches towards excising curvature singularities from numerical simulations
of black hole spacetimes. So far it has only been actively implemented in the
ADM and Einstein-Bianchi 3+1 formulations of the Einstein equations. Recently,
an approach closely related to the ADM one, commonly referred to as as
``conformal ADM'' (CADM) has shown excellent results when modeling waves on
flat spacetimes and black hole spacetimes where singularity avoiding slices are
used to deal with the singularity. In these cases, the use of CADM has yielded
longer evolutions and better outer boundary dependence than those obtained with
the ADM one. If this success translates to the case where excision is
implemented, then the CADM formulation will likely be a prime candidate for
modeling generic black hole spacetimes. In the present work we investigate the
applicability of causal differencing to CADM, presenting the equations in a
convenient way for such a goal and compare its application with the ADM
approach in 1D.

</DOC>
<DOC>
<DOCNO> 116893 </DOCNO>
RF Cell Modeling and Experiments for Wakefield Minimization in DARHT-II


  Electron beams of linear induction accelerators experience deflective forces
caused by RF fields building up as a result of accelerating cavities of finite
size. These forces can significantly effect the beam when a long linac composed
of identical cells is assembled. Recent techniques in computational modeling,
simulation, and experiments for 20 MeV DARHT-II (Dual Axis Radiographic
Hydrodynamic Test) accelerator cells were found to reduce the wakefield
impedance of the cells from 800 ohms/meter to 350 ohms/meter and experimental
results confirm the results of the modeling efforts. Increased performance of
the cell was obtained through a parametric study of the accelerator structure,
materials, material tuning, and geometry. As a result of this effort, it was
found that thickness-tuned ferrite produced a 50% deduction in the wakefield
impedance in the low frequency band and was easily tunable based on the
material thickness. It was also found that shaped metal sections allow for
high-Q resonances to be de-tuned, thus decreasing the amplitude of the
resonance and increasing the cell s performance. For the geometries used for
this cell, a roughly 45 degree angle had the best performance in affecting the
wakefield modes.

</DOC>
<DOC>
<DOCNO> 102843 </DOCNO>
Geometry of GL_n(C) on infinity: complete collineations, projective


  Consider a finite dimensional (generally reducible) polynomial representation
\rho of GL_n. A projective compactification of GL_n is the closure of
\rho(GL_n) in the space of all operators defined up to a factor (this class of
spaces can be characterized as equivariant projective normal compactifications
of GL_n). We give an expicit description for all projective compactifications.
We also construct explicitly (in elementary geometrical terms) a universal
object for all projective compactifications of GL_n.

</DOC>
<DOC>
<DOCNO> 151548 </DOCNO>
Correspondence between the XXZ model in roots of unity and the


  We consider the integrable XXZ model with special open boundary conditions
that renders its Hamiltonian ${SU(2)}_q$ symmetric, and the one-dimensional
quantum Ising model with four different boundary conditions. We show that for
each boundary condition the Ising quantum chain is exactly given by the Minimal
Model of integrable lattice theory $LM(3, 4)$. This last theory is obtained as
the result of the quantum group reduction of the XXZ model at anisotropy
$\Delta=(q + q^{-1})/2=\sqrt{2}/2$, with a number of sites in the latter
defined by the type of boundary conditions.

</DOC>
<DOC>
<DOCNO> 178956 </DOCNO>
Ground state correlations and anharmonicity of vibrations


  A consistent treatment of the ground state correlations beyond the random
phase approximation including their influence on the pairing and phonon-phonon
coupling in nuclei is presented. A new general system of nonlinear equations
for the quasiparticle phonon model (QPM) is derived. It is shown that this
system contains as a particular case all equations derived for the QPM early.
New additional Pauli principle corrections resulting in the anharmonical shifts
of energies of the two-phonon configurations are found. A correspondence
between the generalized QPM equations and the nuclear field theory is
discussed.

</DOC>
<DOC>
<DOCNO> 152424 </DOCNO>
Gauge Fields and Fermions in Tachyon Effective Field Theories


  In this paper we incorporate gauge fields into the tachyon field theory
models for unstable D-branes in bosonic and in Type II string theories. The
chosen couplings yield massless gauge fields and an infinite set of equally
spaced massive gauge fields on codimension one branes. A lack of a continuum
spectrum is taken as evidence that the stable tachyon vacuum does not support
conventional gauge excitations. For the bosonic string model we find two
possible solvable couplings, one closely related to Born-Infeld forms and the
other allowing a detailed comparison to the open string modes on bosonic
D-branes. We also show how to include fermions in the type II model. They
localize correctly on stable codimension one branes resulting in bose-fermi
degeneracy at the massless level. Finally, we establish the solvability of a
large class of models that include kinetic terms with more than two
derivatives.

</DOC>
<DOC>
<DOCNO> 119045 </DOCNO>
The Magnetic Geometry of Pulsed Astrophysical Jets


  Hypersonic, highly collimated, mass outflows ({\it jets}) are a ubiquitous
phenomena in astrophysics. While the character of the jets differ, many exhibit
some form of quasi-periodic clumping indicating the jet source is episodic or
{\it pulsed}. The presence of pulsed jets in so many astrophysical contexts
suggests a common formation mechanism. Such a process seems to have been found
in {\it Magneto-centrifugal launching}, the combination of magnetic and
centrifugal forces that occurs when a magnetized gaseous accretion disk orbits
a central gravitating source. Observations of strong magnetic fields in jets
are, however, rare or indirect. Thus the presence and effects of magnetic
fields in YSO jets remains an unresolved issue of the highest importance. In
this letter we focus on what should be expected of the structure of the fields
in pulsed YSO jets. We show that combining velocity variability with an initial
field configuration consistent with collimated, Magneto-centrifugally launched
jets leads to a clear set of predictions concerning the geometry and relative
strength of the magnetic field components in evolving YSO (and perhaps other)
jets.

</DOC>
<DOC>
<DOCNO> 85282 </DOCNO>
Vacuum polarization of massive scalar fields in the spacetime of the


  The approximate renormalized stress-energy tensor of the quantized massive
conformally coupled scalar field in the spacetime of electrically charged
nonlinear black hole is constructed. It is achieved by functional
differentiation of the lowest order of the DeWitt-Schwinger effective action
involving coincidence limit of the Hadamard-Minakshisundaram-DeWitt-Seely
coefficient $a_{3}.$ The result is compared with the analogous result derived
for the Reissner-Nordstr\"om black hole. It is shown that the most important
differences occur in the vicinity of the event horizon of the black hole near
the extremality limit. The structure of the nonlinear black hole is briefly
studied by means of the Lambert functions.

</DOC>
<DOC>
<DOCNO> 71625 </DOCNO>
Analytical Result for Dimensionally Regularized Massless Master


  The dimensionally regularized massless non-planar double box Feynman diagram
with powers of propagators equal to one, one leg off the mass shell, i.e. with
p_1^2=q^2\neq 0, and three legs on shell, p_i^2=0, i=2,3,4, is analytically
calculated for general values of q^2 and the Mandelstam variables s,t and u
(not necessarily restricted by the physical condition s+t+u=q^2). An explicit
result is expressed through (generalized) polylogarithms, up to the fourth
order, dependent on rational combinations of q^2,s,t and u, and simple finite
two- and three fold Mellin--Barnes integrals of products of gamma functions
which are easily numerically evaluated for arbitrary non-zero values of the
arguments.

</DOC>
<DOC>
<DOCNO> 101056 </DOCNO>
Universal homotopy theories


  Given a small category C, we show that there is a universal way of expanding
C into a model category, essentially by formally adjoining homotopy colimits.
The technique of localization becomes a method for imposing `relations' into
these universal gadgets. The paper develops this formalism and discusses
various applications, for instance to the study of homotopy colimits, the
Dwyer-Kan theory of framings, and to the homotopy theory of schemes.

</DOC>
<DOC>
<DOCNO> 120771 </DOCNO>
Blob ejection from advection-dominated accretion flow: observational


  There is increasing evidence for the presence of an optically thin
advection-dominated accretion flow (ADAF) in low luminosity active galactic
nuclei and radio-loud quasars. The present paper is devoted to explore the fate
of a blob ejected from an ADAF, and to discuss its observational consequences.
It is inevitable for the ejected blob to drastically expand into its
surroundings. Consequently, it is expected that a group of relativistic
electrons should be accelerated, which may lead to nonthermal flares, since a
strong shock will be formed by the interaction between the blob and its
surroundings. Then the blob cools down efficiently, leading to the appearance
of recombination lines about $10^5$s after its ejection from an ADAF. We apply
this model to NGC 4258 for some observational prediction, and to PKS 2149--306
for the explanation of observational evidence. Future simultaneous observations
of recombination X-ray lines and continuum emission are highly desired to test
the present model.

</DOC>
<DOC>
<DOCNO> 120414 </DOCNO>
The evolution of the color gradients of early-type cluster galaxies


  We investigate the origin of color gradients in cluster early-type galaxies
to probe whether pure age or pure metallicity gradients can explain the
observed data in local and distant (z approx 0.4) samples. We measure the
surface brightness profiles of the 20 brightest early-type galaxies of
CL0949+44 (hereafter CL0949) at redshift z=0.35-0.38 from HST WF2 frames taken
in the filters F555W, F675W, F814W. We determine the color profiles (V-R)(r),
(V-I)(r), and (R-I)(r) as a function of the radial distance r in arcsec, and
fit logarithmic gradients in the range -0.2 to 0.1 mag per decade. These values
are similar to what is found locally for the colors (U-B), (U-V), (B-V) which
approximately match the (V-R), (V-I), (R-I) at redshift approx 0.4. We analyse
the results with up to date stellar population models. We find that passive
evolution of metallicity gradients (approx 0.2 dex per radial decade) provides
a consistent explanation of the local and distant galaxies' data. Invoking pure
age gradients (with fixed metallicity) to explain local color gradients
produces too steep gradients at redshifts z approx 0.4. Pure age gradients are
consistent with the data only if large present day ages (>=15 Gyr) are assumed
for the galaxy centers.

</DOC>
<DOC>
<DOCNO> 10794 </DOCNO>
The Effect of Interaction on Shot Noise in The Quantum Limit


  We employ a non-linear sigma model defined on a Keldysh contour to study the
current and the current noise in a diffusive micro-bridge in the presence of
electron-electron interactions. Out of equilibrium the fluctuation-dissipation
theorem (FDT) does not apply, hence these two quantities are not simply
interrelated. For a two-dimensional electron gas (2DEG) we obtain logarithmic
singularities in the low frequency limit. PACS Nos. 71.10.Ay, 71.23.An,
73.50.Td

</DOC>
<DOC>
<DOCNO> 101010 </DOCNO>
Brill-Noether Loci and the Gonality Stratification of $M_g$


  A Brill-Noether locus is a subvariety of M_g consisting of curves having
certain linear series g^r_d. We study the relative position of Brill-Noether
loci with respect to the gonality stratification of M_g. We construct smooth
curves in P^r of given degree and genus and having the `expected' gonality. As
an application we give a new proof of our result about the Kodaira dimension of
the moduli space of curves of genus 23.

</DOC>
<DOC>
<DOCNO> 100811 </DOCNO>
Approximate factorization and concentration for characters of symmetric


  We prove a factorization-concentration result for characters of symmetric
groups. This is then applied to the asymptotic behaviour of the decomposition
of the tensor representations. There are connections with the Pastur-Marcenko
distribution of random matrix theory, and freely infinitely divisible
distributions.

</DOC>
<DOC>
<DOCNO> 68606 </DOCNO>
Pursuing the origin of electroweak symmetry breaking: a 'Bayesian


  High-energy data has been accumulating over the last ten years, and it should
not be ignored when making decisions about the future experimental program. In
particular, we argue that the electroweak data collected at LEP, SLC and
Tevatron indicate a light scalar particle with mass less than 500 GeV. This
result is based on considering a wide variety of theories including the
Standard Model, supersymmetry, large extra dimensions, and composite models. We
argue that a high luminosity, 600 GeV e+e- collider would then be the natural
choice to feel confident about finding and studying states connected to
electroweak symmetry breaking. We also argue from the data that worrying about
resonances at multi-TeV energies as the only signal for electroweak symmetry
breaking is not as important a discovery issue for the next generation of
colliders. Such concerns should perhaps be replaced with more relevant
discovery issues such as a Higgs boson that decays invisibly, and ``new
physics'' that could conspire with a heavier Higgs boson to accommodate
precision electroweak data. An e+e- collider with energy less than about 600
GeV is ideally suited to cover these possibilities.

</DOC>
<DOC>
<DOCNO> 118350 </DOCNO>
Low Frequency Radio Pulses from Gamma-Ray Bursts?


  Gamma-ray bursts, if they are generated in the process of interaction between
relativistic strongly magnetized winds and an ambient medium, may be
accompanied by very short pulses of low-frequency radio emission. The bulk of
this emission is expected to be at the frequencies of $\sim 0.1-1$ MHz and
cannot be observed. However, the high-frequency tail of the low-frequency radio
emission may reach a few ten MHz and be detected, especially if the strength of
the magnetic field of the wind is extremely high.

</DOC>
<DOC>
<DOCNO> 8046 </DOCNO>
Low-frequency peak in the magnetoconductivity of a non-degenerate 2D


  We study the frequency-dependent magnetoconductivity of a strongly correlated
nondegenerate 2D electron system in a quantizing magnetic field. We first
restore the single-electron conductivity from calculated 14 spectral moments.
It has a maximum for omega ~ gamma (hbar gamma is the disorder-induced width of
the Landau level), and scales as a power of omega for omega ->0, with a
universal exponent. Even for strong coupling to scatterers, the
electron-electron interaction modifies the conductivity for low and high
frequencies, and gives rise to a nonzero static conductivity. We analyze the
full many-electron conductivity, and discuss the experiment.

</DOC>
<DOC>
<DOCNO> 71954 </DOCNO>
Expansion of bound-state energies in powers of m/M


  We describe a new approach to computing energy levels of a non-relativistic
bound-state of two constituents with masses M and m, by a systematic expansion
in powers of m/M. After discussing the method, we demonstrate its potential
with an example of the radiative recoil corrections to the Lamb shift and
hyperfine splitting relevant for the hydrogen, muonic hydrogen, and muonium. A
discrepancy between two previous calculations of O(alpha(Zalpha)^5 m^2/M)
radiative recoil corrections to the Lamb shift is resolved and several new
terms of O(alpha(Zalpha)^5 m^4/M^3) and higher are obtained.

</DOC>
<DOC>
<DOCNO> 151683 </DOCNO>
Conformal and Quasiconformal Realizations of Exceptional Lie Groups


  We present a nonlinear realization of E_8 on a space of 57 dimensions, which
is quasiconformal in the sense that it leaves invariant a suitably defined
``light cone'' in 57 dimensions. This realization, which is related to the
Freudenthal triple system associated with the unique exceptional Jordan algebra
over the split octonions, contains previous conformal realizations of the lower
rank exceptional Lie groups on generalized space times, and in particular a
conformal realization of E_7 on a 27 dimensional vector space which we exhibit
explicitly. Possible applications of our results to supergravity and M-Theory
are briefly mentioned.

</DOC>
<DOC>
<DOCNO> 40260 </DOCNO>
Commutators of Lepton Mass Matrices, CP Violation, and Matter Effects in


  We introduce the commutators of lepton mass matrices to describe the
phenomenon of lepton flavor mixing, and establish their relations to the
effective Hamiltonians responsible for the propagation of Dirac and Majorana
neutrinos. The determinants of those commutators are invariant under matter
effects, leading to an instructive relationship between the universal
CP-violating parameters in vacuum and in matter. In the scenario of low-energy
(100 MeV \leq E \leq 1 GeV) and medium-baseline (100 km \leq L \leq 400 km)
neutrino experiments, we illustrate the features of lepton flavor mixing and CP
violation. The terrestrial matter effects on CP- and T-violating asymmetries in
\nu_\mu \to \nu_e and $\bar{\nu}_\mu \to \bar{\nu}_e neutrino oscillations are
also discussed. We demonstrate that a relatively pure signal of leptonic CP
violation at the percent level can be established from such medium-baseline
experiments with low-energy neutrino beams.

</DOC>
<DOC>
<DOCNO> 84116 </DOCNO>
Unification of Weak and Gravitational Interactions Stemming from


  There is a deep interrelationship of the General Theory of Relativity and
weak interactions in the model of Expansive Nondecelerative Universe. This fact
allows an independent determination of the mass of vector bosons Z and W, as
well as the time of separation of electromagnetic and weak interactions.

</DOC>
<DOC>
<DOCNO> 120109 </DOCNO>
Recombination spectra of Helium-Like Ions


  We calculate the recombination spectra of the He-like ions He~I, C~V, N~VI,
O~VII, Ne~IX, Mg~XI, Si~XIII, S~XV, Ar~XVII, Ca~XIX, and Fe~XXV. We include the
following physical processes: radiative recombination, dielectronic
recombination, three-body recombination, electron impact ionization, and
collisional excitation by electrons, protons, and $\alpha$-particles. The
calculations account for the effects of lowering of the continuum at high
densities and high density corrections to dielectronic recombination.
  Then we construct models for He-like ions for fast computation of their
spectra. Every model includes 29 bound levels up to n=5 and 6 doubly excited
levels that account for the most important satellite lines. The models are
constructed in a way that allows for proper approach to LTE under appropriate
conditions. These models can simultaneously solve for the H/He-like ionization
balance in photoionized or collisionally ionized plasmas and compute emission
spectra including the combined effects of radiative and dielectronic
recombination, collisional excitation, photoionization from excited levels,
fluorescence, and line trapping. The models can be used for any temperature
between 100 and $10^9$K and electron densities of up to $10^{18}$ \cm3. The
models can be easily used within spectral modeling codes or as stand-alone
tools for spectral analysis.
  We present comparisons between the results of the present models and previous
work. Significant differences are found between the present effective
recombination rate coefficients to the $n=2$ and those of previous estimates.
Later, we study various emission line ratio diagnostics under collisional
ionization and photoionized conditions.

</DOC>
<DOC>
<DOCNO> 121532 </DOCNO>
The minimum orbital period in thermal-timescale mass transfer


  We show that the usual picture of supersoft X-ray binary evolution as driven
by conservative thermal-timescale mass transfer cannot explain the short
orbital periods of RX J0537.7-7034 (3.5 hr) and 1E 0035.4-7230 (4.1 hr).
Non-conservative evolution may produce such periods, but requires very
significant mass loss, and is highly constrained.

</DOC>
<DOC>
<DOCNO> 174592 </DOCNO>
First observation of 55,56Zn


  In an experiment at the SISSI/LISE3 facility of GANIL, the most proton-rich
zinc isotopes 55,56Zn have been observed for the first time. The experiment was
performed using a high-intensity 58Ni beam at 74.5 MeV/nucleon impinging on a
nickel target. The identification of 55,56Zn opens the way to 54Zn, a good
candidate for two-proton radioactivity according to theoretical predictions.

</DOC>
<DOC>
<DOCNO> 10096 </DOCNO>
Evaluation of configurational entropy of a model liquid from computer


  Computer simulations have been employed in recent years to evaluate the
configurational entropy changes in model glass-forming liquids. We consider two
methods, both of which involve the calculation of the `intra-basin' entropy as
a means for obtaining the configurational entropy. The first method involves
the evaluation of the intra-basin entropy from the vibrational frequencies of
inherent structures, by making a harmonic approximation of the local potential
energy topography. The second method employs simulations that confine the
liquid within a localized region of configuration space by the imposition of
constraints; apart from the choice of the constraints, no further assumptions
are made. We compare the configurational entropies estimated for a model liquid
(binary mixture of particles interacting {\it via} the Lennard-Jones potential)
for a range of temperatures, at fixed density.

</DOC>
<DOC>
<DOCNO> 119002 </DOCNO>
The Orbital Light Curve of Aquila X-1


  We obtained R- and I-band CCD photometry of the soft X-ray transient/neutron-
star binary Aql X-1 in 1998 June while it was at quiescence. We find that its
light curve is dominated by ellipsoidal variations, although the ellipsoidal
variations are severely distorted and have unequal maxima. After we correct for
the contaminating flux from a field star located only 0.46" away, the
peak-to-peak amplitude of the modulation is ~0.25 mag in the R band, which
requires the orbital inclination to be greater than 36 degrees. The orbital
period we measure is consistent with the 18.95 h period measured by Chevalier &
Ilovaisky (1998). During its outbursts the light curve of Aql X-1 becomes
single humped. The outburst light curve observed by Garcia et al. (1999) agrees
in phase with our quiescent light curve. We show that the single humped
variation is caused by a ``reflection effect,'' that is, by heating of the side
of the secondary star facing towards the neutron star.

</DOC>
<DOC>
<DOCNO> 123085 </DOCNO>
Measurements of r-process nuclei


  Progress in the astrophysical understanding of r-process nucleosynthesis also
depends on the knowledge of nuclear-physics quantities of extremely
neutron-rich isotopes. In this context, experiments at CERN-ISOLDE have played
a pioneering role in exploring new shell-structure far from stability. Possible
implications of new nuclear-data input on the reproduction of r-abundance
observations are presented.

</DOC>
<DOC>
<DOCNO> 70109 </DOCNO>
Two-Fermion Production in Electron-Positron Collisions


  This report summarizes the results of the two-fermion working group of the
LEP2-MC workshop, held at CERN from 1999 to 2000. Recent developments in the
theoretical calculations of the two fermion production process in the
electron-positron collision at LEP2 center of the mass energies are reported.
The Bhabha process and the production of muon, tau, neutrino and quark pairs is
covered. On the basis of comparison of various calculations, theoretical
uncertainties are estimated and compared with those needed for the final LEP2
data analysis. The subjects for the further studies are identified.

</DOC>
<DOC>
<DOCNO> 121606 </DOCNO>
Modeling gas and stellar kinematics in disc galaxies


  We present V-band surface photometry and major-axis kinematics of stars and
ionized gas of three early-type spiral galaxies, namely NGC 772, NGC 3898 and
NGC 7782. For each galaxy we built a self-consistent Jeans model for the
stellar kinematics, adopting the light distribution of bulge and disc derived
by means of a two-dimensional parametric photometric decomposition. This
allowed us to investigate the presence of non-circular gas motions, and derive
the mass distribution of luminous and dark matter in these objects. We found
that the observed gas rotation corresponds to the circular velocity except for
the innermost region (|r|<8") of NGC 3898. This behaviour is quite common,
although not ubiquitous, in the few bulge-dominated galaxies, for which
dynamical modeling allows the comparison between the gas velocity and the
circular speed.

</DOC>
<DOC>
<DOCNO> 9237 </DOCNO>
Relevance of memory in Minority Games


  By considering diffusion on De Bruijn graphs, we study in details the
dynamics of the histories in the Minority Game, a model of competition between
adaptative agents. Such graphs describe the structure of temporal evolution of
$M$ bits strings, each node standing for a given string, i.e. a history in the
Minority Game. We show that the frequency of visit of each history is not given
by $1/2^M$ in the limit of large $M$ when the transition probabilities are
biased. Consequently all quantities of the model do significantly depend on
whether the histories are real, or uniformly and randomly sampled. We expose a
self-consistent theory of the case of real histories, which turns out to be in
very good agreement with numerical simulations.

</DOC>
<DOC>
<DOCNO> 8554 </DOCNO>
Breakdown of Migdal-Eliashberg Theory in Rb$_3$C$_{60}$


  This paper has been withdrawn. An extended version of this work can be found
in
 E. Cappelluti, C. Grimaldi, L. Pietronero, S. Straessler:
 Phys. Rev. Lett. 85, 4771 (2000) [cond-mat/0105560] and
 E. Cappelluti, C. Grimaldi, L. Pietronero, S. Straessler, G.A. Ummarino:
 Eur. Phys. J. B 21, 383 (2001) [cond-mat/0104457]

</DOC>
<DOC>
<DOCNO> 152041 </DOCNO>
Anomalies and Star Products


  A formulation of anomalies in terms of star products is suggested which
promises insight from an alternative and unifying point of view.

</DOC>
<DOC>
<DOCNO> 8429 </DOCNO>
Packing of Compressible Granular Materials


  3D Computer simulations and experiments are employed to study random packings
of compressible spherical grains under external confining stress. Of particular
interest is the rigid ball limit, which we describe as a continuous transition
in which the applied stress vanishes as (\phi-\phi_c)^\beta, where \phi is the
(solid phase) volume density. This transition coincides with the onset of shear
rigidity. The value of \phi_c depends, for example, on whether the grains
interact via only normal forces (giving rise to random close packings) or by a
combination of normal and friction generated transverse forces (producing
random loose packings). In both cases, near the transition, the system's
response is controlled by localized force chains. As the stress increases, we
characterize the system's evolution in terms of (1) the participation number,
(2) the average force distribution, and (3) visualization techniques.

</DOC>
<DOC>
<DOCNO> 83461 </DOCNO>
The Use of Instrumentation in Grammar Engineering


  This paper explores the usefulness of a technique from software engineering,
code instrumentation, for the development of large-scale natural language
grammars. Information about the usage of grammar rules in test and corpus
sentences is used to improve grammar and testsuite, as well as adapting a
grammar to a specific genre. Results show that less than half of a
large-coverage grammar for German is actually tested by two large testsuites,
and that 10--30% of testing time is redundant. This methodology applied can be
seen as a re-use of grammar writing knowledge for testsuite compilation.

</DOC>
<DOC>
<DOCNO> 69417 </DOCNO>
Radion Mass is Milli-eV in the Goldberger-Wise Stabilization Mechanism


  A complete calculation of the radion mass has been given by Tanaka and
Montes, hep-th/0001092, and also by Csaki, Graesser and Kribs (in preparation),
which both obtain the TeV-scale. It seems likely that the problem with our
computation was neglect of the back-reaction of the scalar field on the
graviton zero mode, and consequent contributions to the radion kinetic term
from the gravitational part of the Lagrangian. We thank T. Tanaka and C. Csaki
for pointing out their results to us.

</DOC>
<DOC>
<DOCNO> 68326 </DOCNO>
Right-Handed Vector V and Axial A Couplings in Weak Interactions


  In this paper a scenario admitting the participation of right-handed vector V
and axial A couplings with the conservation of the left-handed standard (V, A)
couplings is considered. The research is based on the muon capture by proton.
We consider muon capture at the level of the Fermi theory (four-fermion point
interaction). Neutrinos are assumed to be massive and to be Dirac fermions. We
propose neutrino observables, it means transverse components of the neutrino
polarization, both T-odd and T-even. That would be a unique test verifying the
participation of the right-handed (V, A) couplings in muon capture. The effects
of the transverse neutrino polarization connected with the right-handed (V, A)
couplings may be of the order of 7%. Our considerations are model-independent.
We give the lower bound of 305 GeV on the mass of the right-handed gauge boson.
This limit is compatible with the current bounds on the mass of the
right-handed vector boson received from the weak interaction processes at low
energy.

</DOC>
<DOC>
<DOCNO> 100428 </DOCNO>
The identification capacity and resolvability of channels with input


  Given a general channel, we first formulate the idetification capacity
problem as well as the resolvability problem with input cost constraint in as
the general form as possible, along with relevant fundamental theorems. Next,
we establish some mild sufficient condition for the key lemma linking the
identification capacity with the resolvability to hold for the continuous input
alphabet case with input cost constraint. Under this mild condition, it is
shown that we can reach the {\em continuous}-input fundamental theorem of the
same form as that for the fundamental theorem with {\em finite} input alphabet.
Finally, as important examples of this continuous-input fundamental theorem, we
show that the identification capacity as well as the resolvability coincides
with the channel capacity for stationary additive white (and also non-white)
Gaussian noise channels.

</DOC>
<DOC>
<DOCNO> 121744 </DOCNO>
Dwarf Spheroidal Galaxies in the M81 Group Imaged with WFPC2


  We obtained HST/WFPC2 images of the dwarf spheroidal (dSph) galaxies K61,
K63, K64, DDO78, BK6N, and kk77 in the M81 group. Our color-magnitude diagrams
show red giant branches with tips (TRGB) falling within the range of I = [23.8
-24.0] mag. The derived true distance moduli (DM) of the 6 dSphs ranging from
27.71 to 27.93 mag are consistent with their membership in the group. Given
accurate distances of 5 other group members, which have been derived via TRGB
or cepheids, the mean DM of the M81 group is (27.84+-0.05) mag. We find the
difference of the mean distances to the M81 and NGC2403 groups to be D_M81 -
D_NGC2403 =(0.5+-0.2) Mpc, which yields a deprojected separation of 0.9 Mpc.
With respect to the Local group, M81 and NGC2403 have radial velocities of 106
and 267 km/s respectively, while the velocities of the group centroids are 142
and 281 km/s. The higher velocity of the closer system may indicate that these
groups are moving towards each other, similar to the Milky Way and M31 in the
Local group. Several globular cluster candidates have been identified in the
galaxies.

</DOC>
<DOC>
<DOCNO> 151964 </DOCNO>
On Exact Tachyon Potential in Open String Field Theory


  In these notes we revisit the tachyon lagrangian in the open string field
theory using background independent approach of Witten from 1992. We claim that
the tree level lagrangian (up to second order in derivatives and modulo some
class of field redefinitions) is given by $L = e^{-T} (\partial T)^2 +
(1+T)e^{-T}$. Upon obvious change of variables this leads to the potential
energy $-\phi^2 \log {\phi^2 \over e}$ with canonical kinetic term. This
lagrangian may be also obtained from the effective tachyon lagrangian of the
p-adic strings in the limit $p\to 1$. Applications to the problem of tachyon
condensation are discussed.

</DOC>
<DOC>
<DOCNO> 11129 </DOCNO>
Effect of Strong Correlation on the Electron-Phonon Interaction


  High-$T_c$ superconductors are usually described as strongly correlated
electronic systems. This feature deeply affects the one-particle and
two-particle properties of the system. In particular, a large incoherent
background developes on the top of a narrow quasi-particle peak in the
one-electron spectral function. We schematize this structure with a simple
phenomenological form. The corresponding Green's function is employed to
calculate the charge response of the system taking into account in a proper way
strong correlation effects. The effective charge interaction acquires a
structure in the exchanged momentum space with a predominance of forward
scattering, in agreement with previous numerical calculations. The consequences
of the momentum dependence of the interaction are discussed in the framework of
the nonadiabatic theory of superconductivity proposed for the high-$T_c$
materials.

</DOC>
<DOC>
<DOCNO> 11785 </DOCNO>
Brownian Dynamics of a Sphere Between Parallel Walls


  We describe direct imaging measurements of a colloidal sphere's diffusion
between two parallel surfaces. The dynamics of this deceptively simple
hydrodynamically coupled system have proved difficult to analyze. Comparison
with approximate formulations of a confined sphere's hydrodynamic mobility
reveals good agreement with both a leading-order superposition approximation as
well as a more general all-images stokeslet analysis.

</DOC>
<DOC>
<DOCNO> 151794 </DOCNO>
On the universality of string theory


  String theory is accused by some of its critics to be a purely abstract
mathematical discipline, having lost the contact to the simple yet deeply
rooted questions which physics provided until the beginning of this century. We
argue that, in contrary, there are indications that string theory might be
linked to a fundamental principle of a quantum computational character. In
addition, the nature of this principle might be capable to provide some new
insight into the question of universality of string theory.

</DOC>
<DOC>
<DOCNO> 151897 </DOCNO>
Stable Massive States in 1+1 Dimensional NCOS


  We study the case of open string theory on a D1-brane in a critical electric
field. It was argued in hep-th/0006085 that the massless open string modes of
this theory decouple from the massive modes, corresponding to a decoupling of
the U(1) degrees of freedom in the U(N) gauge theory dual. To provide further
support for the decoupling, we present several examples of open string disk
amplitudes. Because of the decoupling, many of the massive open string states
are stable, indicating the presence of a number of correspondingly stable
states in the gauge theory. We provide a lengthy list of these stable states.
However, when the theory is compactified in the spatial direction of the
electric field, we demonstrate that sufficiently massive such states may decay
into wound closed strings.

</DOC>
<DOC>
<DOCNO> 68964 </DOCNO>
Nuclear Muon Capture on the Proton and 3He within the Standard Model and


  Nuclear muon capture on the proton and $^3$He is considered both within and
beyond the Standard Model in terms as general as is possible. Explicit and
precise analytic expressions for all possible observables are given, assuming
only a Dirac neutrino in the limit of vanishing mass. These results allow both
for precision tests of the Standard Model and new physics, as well as for the
assessment of the potential physics reach of experiments designed to measure
specific observables. Using these expressions, stringent constraints can
already be inferred from a recent precision measurement of the statistical
capture rate on $^3$He. Likewise, similar constraints should follow the
completion of a precision measurement in progress of the singlet capture rate
on the proton.

</DOC>
<DOC>
<DOCNO> 100753 </DOCNO>
On the consistency of $P=NP$ with fragments of ZFC whose own consistency


  We formulate the $P<NP$ hypothesis in the case of the satisfiability problem
as a $\Pi ^0_2$ sentence, out of which we can construct a partial recursive
function $f_{\neg A}$ so that $f_{\neg A}$ is total if and only if $P < NP$. We
then show that if $f_{\neg A}$ is total, then it isn't ${\cal T}$--provably
total (where ${\cal T}$ is a fragment of ZFC that adequately extends PA and
whose consistency is of ordinal order). Follows that the negation of $P < NP$,
that is, $P = NP$, is consistent with those ${\cal T}$.

</DOC>
<DOC>
<DOCNO> 84475 </DOCNO>
The Dimensional-Reduction Anomaly in Spherically Symmetric Spacetimes


  In D-dimensional spacetimes which can be foliated by n-dimensional
homogeneous subspaces, a quantum field can be decomposed in terms of modes on
the subspaces, reducing the system to a collection of (D-n)-dimensional fields.
This allows one to write bare D-dimensional field quantities like the Green
function and the effective action as sums of their (D-n)-dimensional
counterparts in the dimensionally reduced theory. It has been shown, however,
that renormalization breaks this relationship between the original and
dimensionally reduced theories, an effect called the dimensional-reduction
anomaly. We examine the dimensional-reduction anomaly for the important case of
spherically symmetric spaces.

</DOC>
<DOC>
<DOCNO> 120213 </DOCNO>
High Energy Neutrinos from Gamma Ray Bursts: Event Rates in Neutrino


  Following Waxman and Bahcall we calculate the event rate, energy and zenith
angle dependence of neutrinos produced in the fireball model of gamma ray
bursts (GRB). We emphasize the primary importance of i) burst-to-burst
fluctuations and ii) absorption of the neutrinos in the Earth. From the
astronomical point of view, we draw attention to the sensitivity of neutrino
measurements to the boost Lorentz factor of the fireball $\Gamma$, which is
central to the fireball model, and only indirectly determined by follow-up
observations. Fluctuations result in single bursts emitting multiple neutrinos,
making it possible to determine the flavor composition of a beam observed after
a baseline of thousands of Megaparsecs.

</DOC>
<DOC>
<DOCNO> 101312 </DOCNO>
Semisimple Frobenius structures at higher genus


  We describe genus g>1 potentials of semisimple Frobenius structures. Our
formula can be considered as a definition in the axiomatic context of Frobenius
manifolds. In Gromov-Witten theory, it becomes a conjecture expressing higher
genus GW-invariants in terms of genus 0 GW-invariants of symplectic manifolds
with generically semisimple quantum cup-product. The conjecture is supported by
the corresponding theorem about equivariant GW-invariants of tori actions with
isolated fixed points. The parallel theory of gravitational descendents is also
presented.

</DOC>
<DOC>
<DOCNO> 40213 </DOCNO>
The MONOLITH project


  MONOLITH is a proposed massive (34 kt) magnetized tracking calorimeter at the
Gran Sasso laboratory in Italy, optimized for the detection of atmospheric muon
neutrinos. The main goal is to establish (or reject) the neutrino oscillation
hypothesis through an explicit observation of the full first oscillation swing.
The Delta m^2 sensitivity range for this measurement comfortably covers the
complete Super-Kamiokande allowed region. Other measurements include studies of
matter effects and the NC/CC and anti-nu/nu ratio, the study of cosmic ray
muons in the multi-TeV range, and auxiliary measurements from the CERN to Gran
Sasso neutrino beam. Depending on approval, data taking with part of the
detector could start in 2004. The detector and its performance are described,
and its potential later use as a neutrino factory detector is addressed.

</DOC>
<DOC>
<DOCNO> 170794 </DOCNO>
Simultaneous minimum-uncertainty measurement of discrete-valued


  We have made the first experimental demonstration of the simultaneous minimum
uncertainty product between two complementary observables for a two-state
system (a qubit). A partially entangled two-photon state was used to perform
such measurements. Each of the photons carries (partial) information of the
initial state thus leaving a room for measurements of two complementary
observables on every member in an ensemble.

</DOC>
<DOC>
<DOCNO> 84632 </DOCNO>
On the determination of the last stable orbit for circular general


  We discuss the analytical determination of the location of the Last Stable
Orbit (LSO) in circular general relativistic orbits of two point masses. We use
several different ``resummation methods'' (including new ones) based on the
consideration of gauge-invariant functions, and compare the results they give
at the third post-Newtonian (3PN) approximation of general relativity. Our
treatment is based on the 3PN Hamiltonian of Jaranowski and Sch\"afer. One of
the new methods we introduce is based on the consideration of the (invariant)
function linking the angular momentum and the angular frequency. We also
generalize the ``effective one-body'' approach of Buonanno and Damour by
introducing a non-minimal (i.e. ``non-geodesic'') effective dynamics at the 3PN
level. We find that the location of the LSO sensitively depends on the
(currently unknown) value of the dimensionless quantity $\oms$ which
parametrizes a certain regularization ambiguity of the 3PN dynamics. We find,
however, that all the analytical methods we use numerically agree between
themselves if the value of this parameter is $\oms\simeq-9$. This suggests that
the correct value of $\oms$ is near -9 (the precise value
$\oms^*\equiv-{47/3}+{41/64}\pi^2=-9.3439...$ seems to play a special role). If
this is the case, we then show how to further improve the analytical
determination of various LSO quantities by using a ``Shanks'' transformation to
accelerate the convergence of the successive (already resummed) PN estimates.

</DOC>
<DOC>
<DOCNO> 13899 </DOCNO>
Reply to a comment on "A Comparison Between Broad Histogram and


  This is a reply to the comment by M. Kastner and M. Promberger 
[cond-mat/0011516] on the paper published in J. Stat. Phys. 99, 691 (2000) 
and also in cond-mat/0002176. We show that all their criticisms do not apply.

</DOC>
<DOC>
<DOCNO> 151983 </DOCNO>
Self-Duality of a Topologically Massive Born-Infeld Theory


  We consider self-duality in a 2+1 dimensional gauge theory containing both
the Born-Infeld and the Chern-Simons terms. We introduce a Born-Infeld inspired
generalization of the Proca term and show that the corresponding self dual
equation is identical to that of the Born-Infeld-Chern-Simons theory.

</DOC>
<DOC>
<DOCNO> 121233 </DOCNO>
Huddled Masses Yearning to Stream Free: Globular Clusters in the Hearts


  Extremely rich populations of globular clusters, numbering ten thousand or
more, surround the central giant galaxies in rich clusters. I discuss some
recent spectroscopic and photometric observations of these rich globular
clusters populations. In very nearby galaxy clusters, the globular cluster
velocities can be used to trace the transition from the galaxy potential to the
larger cluster potential. Beyond cz \approx 3000 km/s, the globulars are too
faint for spectroscopic studies with even the largest telescopes and cease to
be useful dynamical tracers. However, the spatial distribution and size of the
globular population also contains information on the central mass distribution
of the cluster and can be measured out to cz > 20,000 km/s. Overall, the data
suggest that these rich globular cluster populations are comprised of normal,
old globulars, the majority of which were assembled in the cluster centers
before most of the stars in the cD galaxy were formed.

</DOC>
<DOC>
<DOCNO> 118594 </DOCNO>
IRS: the Infrared Spectrograph on SIRTF


  The Infrared Spectrograph (IRS)is one of the three instruments on board the
Space Infrared Telescope Facility (SIRTF) to be launched in December 2001. The
IRS will provide high resolution spectra R~600 from 10--37microns and low
resolution spectra R~60 from 5.3--40microns Its high sensitivity and ``spectral
mapping-mode'' make it a powerful instrument for observing both faint
point-like and extended sources.

</DOC>
<DOC>
<DOCNO> 118704 </DOCNO>
Nonlinear Analysis of Irregular Variables


  The Fourier spectral techniques that are common in Astronomy for analyzing
periodic or multi-periodic light-curves lose their usefulness when they are
applied to unsteady light-curves. We review some of the novel techniques that
have been developed for analyzing irregular stellar light or radial velocity
variations, and we describe what useful physical and astronomical information
can be gained from their use.

</DOC>
<DOC>
<DOCNO> 170517 </DOCNO>
Can We Obtain Quantum Theory From Reasonable Axioms?


  See quant-ph/0101012

</DOC>
<DOC>
<DOCNO> 80733 </DOCNO>
Heavy Quarks on Anisotropic Lattices: The Charmonium Spectrum


  We present results for the mass spectrum of $c{\bar c}$ mesons simulated on
anisotropic lattices where the temporal spacing $a_t$ is only half of the
spatial spacing $a_s$. The lattice QCD action is the Wilson gauge action plus
the clover-improved Wilson fermion action. The two clover coefficients on an
anisotropic lattice are estimated using mean links in Landau gauge. The bare
velocity of light $\nu_t$ has been tuned to keep the anisotropic, heavy-quark
Wilson action relativistic. Local meson operators and three box sources are
used in obtaining clear statistics for the lowest lying and first excited
charmonium states of $^1S_0$, $^3S_1$, $^1P_1$, $^3P_0$ and $^3P_1$. The
continuum limit is discussed by extrapolating from quenched simulations at four
lattice spacings in the range 0.1 - 0.3 fm. Results are compared with the
observed values in nature and other lattice approaches. Finite volume effects
and dispersion relations are checked.

</DOC>
<DOC>
<DOCNO> 116439 </DOCNO>
Search for correlation effects in linear chains of trapped ions


  We report a precise search for correlation effects in linear chains of 2 and
3 trapped Ca+ ions. Unexplained correlations in photon emission times within a
linear chain of trapped ions have been reported, which, if genuine, cast doubt
on the potential of an ion trap to realize quantum information processing. We
observe quantum jumps from the metastable 3d 2D_{5/2} level for several hours,
searching for correlations between the decay times of the different ions. We
find no evidence for correlations: the number of quantum jumps with separations
of less than 10 ms is consistent with statistics to within errors of 0.05%; the
lifetime of the metastable level derived from the data is consistent with that
derived from independent single-ion data at the level of the experimental
errors 1%; and no rank correlations between the decay times were found with
sensitivity to rank correlation coefficients at the level of |R| = 0.024.

</DOC>
<DOC>
<DOCNO> 150697 </DOCNO>
Real-normalized Whitham hierarchies and the WDVV equations


  In this paper we present a construction of a new class of explicit solutions
to the WDVV (or associativity) equations. Our construction is based on a
relationship between the WDVV equations and Whitham (or modulation) equations.
Whitham equations appear in the perturbation theory of exact algebro-geometric
solutions of soliton equations and are defined on the moduli space of algebraic
curves with some extra algebro-geometric data. It was first observed by
Krichever that for curves of genus zero the tau-function of a ``universal''
Whitham hierarchy gives a solution to the WDVV equations. This construction was
later extended by Dubrovin and Krichever to algebraic curves of higher genus.
Such extension depends on the choice of a normalization for the corresponding
Whitham differentials. Traditionally only complex normalization (or the
normalization w.r.t. a-cycles) was considered. In this paper we generalize the
above construction to the real-normalized case.

</DOC>
<DOC>
<DOCNO> 10071 </DOCNO>
Competition between Pauli and orbital effects in a charge-density wave


  We present angular dependent magneto-transport and magnetization measurements
on alpha-(ET)2MHg(SCN)4 compounds at high magnetic fields and low temperatures.
We find that the low temperature ground state undergoes two subsequent
field-induced density-wave type phase transitions above a critical angle of the
magnetic field with respect to the crystallographic axes. This new phase
diagram may be qualitatively described assuming a charge density wave ground
state which undergoes field-induced transitions due to the interplay of Pauli
and orbital effects.

</DOC>
<DOC>
<DOCNO> 39647 </DOCNO>
Search for Unstable Heavy and Excited Leptons at LEP2


  Searches for unstable neutral and charged heavy leptons, N and L+-, and for
excited states of neutral and charged leptons, nu*, e*, mu*, and tau*, have
been performed in e+e- collisions using data collected by the OPAL detector at
LEP. The data analysed correspond to an integrated luminosity of about 58pb-1
at a centre-of-mass energy of 183GeV, and about 10pb-1 each at 161GeV and
172GeV. No evidence for new particles was found. Lower limits on the masses of
unstable heavy and excited leptons are derived. From the analysis of
charged-current, neutral-current, and photonic decays of singly produced
excited leptons, upper limits are determined for the ratio of the coupling to
the compositeness scale, f/Lambda, for masses up to the kinematic limit. For
excited leptons, the limits are established independently of the relative
values of the coupling constants f and f'.

</DOC>
<DOC>
<DOCNO> 71119 </DOCNO>
Fine-tuning the basic forces of nature through the triple-alpha process


  We show that the synthesis of carbon and oxygen through the triple-alpha
process in red giant stars is extremely sensitive to the fine details of the
nucleon-nucleon (N-N) interaction. A +/-0.5% change in the strength of the N-N
force would reduce either the carbon or oxygen abundance by as much as a factor
of 30-1000. This result may be used to constrain some fundamental parameters of
the Standard Model.

</DOC>
<DOC>
<DOCNO> 99708 </DOCNO>
BMO, H^1, and Calderon-Zygmund operators for non doubling measures


  Given a Radon measure $\mu$ on $R^d$, which may be non doubling, we introduce
a space of type BMO with respect to this measure. It is shown that many
properties that hold when $\mu$ is doubling remain valid for the space BMO
introduced in this paper, without assuming $\mu$ doubling. For instance,
Calderon-Zygmund operators which are bounded in $L^2$ are bounded from
$L^\infty$ into the new BMO space. Moreover, a John-Nirenberg inequality is
satisfied, and the predual of BMO is an atomic space $H^1$. Using a sharp
maximal function it is proved that operators bounded from $L^\infty$ into BMO
and from $H^1$ into $L^1$ are also bounded on $L^p$, $1<p<\infty$. This result
gives a new proof of the T(1) theorem for the Cauchy transform with non
doubling measures. Finally, a result about commutators is obtained.

</DOC>
<DOC>
<DOCNO> 117255 </DOCNO>
A Generator of Protein Folding Kinetics States for the


  Two separate algorithms for calculating the intermediate states, using
cellular automata and the initial conditions in the rate matrix for the
diffusion-collision model are introduced. They enable easy and fast
calculations of the folding probabilities of the intermediate states, even for
a very large number of microdomains.

</DOC>
<DOC>
<DOCNO> 83128 </DOCNO>
E-RES: A System for Reasoning about Actions, Events and Observations


  E-RES is a system that implements the Language E, a logic for reasoning about
narratives of action occurrences and observations. E's semantics is
model-theoretic, but this implementation is based on a sound and complete
reformulation of E in terms of argumentation, and uses general computational
techniques of argumentation frameworks. The system derives sceptical
non-monotonic consequences of a given reformulated theory which exactly
correspond to consequences entailed by E's model-theory. The computation relies
on a complimentary ability of the system to derive credulous non-monotonic
consequences together with a set of supporting assumptions which is sufficient
for the (credulous) conclusion to hold. E-RES allows theories to contain
general action laws, statements about action occurrences, observations and
statements of ramifications (or universal laws). It is able to derive
consequences both forward and backward in time. This paper gives a short
overview of the theoretical basis of E-RES and illustrates its use on a variety
of examples. Currently, E-RES is being extended so that the system can be used
for planning.

</DOC>
<DOC>
<DOCNO> 102036 </DOCNO>
Fundamental group of sextics of torus type


  We show that the fundamental group of the complement of any irreducible tame
torus sextics in $\bf P^2$ is isomorphic to $\bf Z_2*\bf Z_3$ except one class.
The exceptional class has the configuration of the singularities
$\{C_{3,9},3A_2\}$ and the fundamental group is bigger than $\bf Z_2*\bf Z_3$.
In fact, the Alexander polynomial is given by $(t^2-t+1)^2$. For the proof, we
first reduce the assertion to maximal curves and then we compute the
fundamental groups for maximal tame torus curves.

</DOC>
<DOC>
<DOCNO> 102045 </DOCNO>
Foliations associated to regular Poisson structures


  A regular Poisson manifold can be described as a foliated space carrying a
tangentially symplectic form. Examples of foliations are produced here that are
not induced by any Poisson structure although all the basic obstructions
vanish.

</DOC>
<DOC>
<DOCNO> 152032 </DOCNO>
Once more on the BPS bound for the susy kink


  We consider a new momentum cut-off scheme for sums over zero-point energies,
containing an arbitrary function f(k) which interpolates smoothly between the
zero-point energies of the modes around the kink and those in flat space. A
term proportional to df(k)/dk modifies the result for the one-loop quantum mass
M^(1) as obtained from naive momentum cut-off regularization, which now agrees
with previous results, both for the nonsusy and susy case. We also introduce a
new regularization scheme for the evaluation of the one-loop correction to the
central charge Z^(1), with a cut-off K for the Dirac delta function in the
canonical commutation relations and a cut-off \Lambda for the loop momentum.
The result for Z^(1) depends only on whether K>\Lambda or K<\Lambda or
K=\Lambda. The last case yields the correct result and saturates the BPS bound,
M^(1)=Z^(1),in agreement with the fact that multiplet shortening does occur in
this N=(1,1) system. We show how to apply mode number regularization by
considering first a kink-antikink system, and also obtain the correct result
with this method. Finally we discuss the relation of these new schemes to
previous approaches based on the Born expansion of phase shifts and
higher-derivative regularization.

</DOC>
<DOC>
<DOCNO> 8096 </DOCNO>
A Remark on One-Dimensional Many-Body Problems with Point Interactions


  The integrability of one dimensional quantum mechanical many-body problems
with general contact interactions is extensively studied. It is shown that
besides the pure (repulsive or attractive) $\delta$-function interaction there
is another singular point interactions which gives rise to a new one-parameter
family of integrable quantum mechanical many-body systems. The bound states and
scattering matrices are calculated for both bosonic and fermionic statistics.

</DOC>
<DOC>
<DOCNO> 11014 </DOCNO>
Quasi-continuous atom laser in the presence of gravity


  We analyse the extraction of a coherent atomic beam from a trapped
Bose-Einstein condensate using a rf transition to a non-trapping state at T=0
K. Our quantum treatment fully takes gravity into account but neglects all
interactions in the free falling beam. We obtain an analytical expression of
the output rate and of the wave function of the extracted beam, i.e. the output
mode of the ``atom laser''. Our model reproduces satisfactorily experimental
data without any adjustable parameter.

</DOC>
<DOC>
<DOCNO> 71925 </DOCNO>
Comparison of Pion-Kaon Scattering in SU(3) Chiral Perturbation Theory


  We establish the framework for the comparison of $\pi K$ scattering
amplitudes from SU(3) chiral perturbation theory with suitable dispersive
representations which result from the combination of certain fixed-t dispersion
relations with dispersion relations on hyperbolic curves. This allows for
predictions for some combinations of low energy constants appearing in higher
order calculations of chiral perturbation theory. Using a simple
parametrization for the lowest partial waves, first estimates for some
combinations are presented.

</DOC>
<DOC>
<DOCNO> 170722 </DOCNO>
Interfering with decay of a single photon in microwave cavities through


  The decay of a single photon in a microwave cavity is shown to be retarded by
interaction with a resonant two-level atom in the experimental setup recently
developed by Nogues and co-workers [see G. Nogues, A. Rauschenbeutel, S.
Osnaghi, M. Brune, J. M. Raimond and S. Haroche, Nature vol 400, 239(1999)].
The effect may be interpreted in terms of the temporary removal of the photon
from the cavity thereby protecting it from the effects of the environment to
wich the cavity is coupled. Realistic parameters lead to a significative
increase of the survival probability of the photon subsequently to the
monitoring interaction.

</DOC>
<DOC>
<DOCNO> 9519 </DOCNO>
Basic considerations on broken-symmetry states of organic


  In this brief account, we shall review the different mechanisms giving rise
to itinerant and localized antiferromagnetism in quasi-one-dimensional organic
conductors: the Bechgaard salts and their sulfur analogs. We will then focus on
the problem of spin correlations and their impact on the pairing mechanism for
organic superconductivity.

</DOC>
<DOC>
<DOCNO> 67747 </DOCNO>
A Monte Carlo for BFKL Physics


  Virtual photon scattering in e^+e^- collisions can result in events with the
electron-positron pair at large rapidity separation with hadronic activity in
between. The BFKL equation resums large logarithms that dominate the cross
section for this process. We report here on a Monte Carlo method for solving
the BFKL equation that allows kinematic constraints to be taken into account.
The application to e^+e^- collisions is in progress.

</DOC>
<DOC>
<DOCNO> 70196 </DOCNO>
Form Factors for Semileptonic B -> pi and D -> pi Decays from the Omnes


  We use the Omnes representation to obtain the q-squared dependence of the
form factors f+ and f0 for semileptonic H -> pi decays from the elastic pi H ->
pi H scattering amplitudes, where H denotes a B or D meson. The scattering
amplitudes used satisfy elastic unitarity and are calculated from two-particle
irreducible amplitudes obtained using tree-level heavy meson chiral
perturbation theory (HMChPT). The q-squared dependences for the form factors
agree with lattice QCD results when the HMChPT coupling constant, g, takes
values smaller than 0.32, and confirm the milder dependence of f0 on q-squared
found in sumrule calculations.

</DOC>
<DOC>
<DOCNO> 151599 </DOCNO>
Consistency conditions and trace anomalies in six dimensions


  Conformally invariant quantum field theories develop trace anomalies when
defined on curved backgrounds. We study again the problem of identifying all
possible trace anomalies in d=6 by studying the consistency conditions to
derive their 10 independent solutions. It is known that only 4 of these
solutions represent true anomalies, classified as one type A anomaly, given by
the topological Euler density, and three type B anomalies, made up by three
independent Weyl invariants. However, we also present the explicit expressions
of the remaining 6 trivial anomalies, namely those that can be obtained by the
Weyl variation of local functionals. The knowledge of the latter is in general
necessary to disentangle the universal coefficients of the type A and B
anomalies from calculations performed on concrete models.

</DOC>
<DOC>
<DOCNO> 100587 </DOCNO>
Algebraic Geometry Over Four Rings and the Frontier to Tractability


  We present some new and recent algorithmic results concerning polynomial
system solving over various rings. In particular, we present some of the best
recent bounds on: (a) the complexity of calculating the complex dimension of an
algebraic set, (b) the height of the zero-dimensional part of an algebraic set
over C, and (c) the number of connected components of a semi-algebraic set. We
also present some results which significantly lower the complexity of deciding
the emptiness of hypersurface intersections over C and Q, given the truth of
the Generalized Riemann Hypothesis. Furthermore, we state some recent progress
on the decidability of the prefixes \exists\forall\exists and
\exists\exists\forall\exists, quantified over the positive integers. As an
application, we conclude with a result connecting Hilbert's Tenth Problem in
three variables and height bounds for integral points on algebraic curves.
  This paper is based on three lectures presented at the conference
corresponding to this proceedings volume. The titles of the lectures were
``Some Speed-Ups in Computational Algebraic Geometry,'' ``Diophantine Problems
Nearly in the Polynomial Hierarchy,'' and ``Curves, Surfaces, and the Frontier
to Undecidability.''

</DOC>
<DOC>
<DOCNO> 118123 </DOCNO>
Gravitational Clustering from Chi^2 Initial Conditions


  We consider gravitational clustering from primoridal non-Gaussian
fluctuations provided by a $\chi^2$ model, as motivated by some models of
inflation. The emphasis is in signatures that can be used to constrain this
type of models from large-scale structure galaxy surveys. Non-Gaussian initial
conditions provide additional non-linear couplings otherwise forbidden by
symmetry that cause non-linear gravitational corrections to become important at
larger scales than in the Gaussian case. In fact, the lack of hierarchical
scaling in the initial conditions is partially restored by gravitational
evolution at scales $k> 0.1$ h/Mpc. However, the bispectrum shows much larger
amplitude and residual scale dependence not present in evolution from Gaussian
initial conditions that can be used to test this model against observations. We
include the effects of biasing and redshift distortions essential to compare
this model with galaxy redshift surveys. We also discuss the effects of
primordial non-Gaussianity on the redshift-space power spectrum and show that
it changes the shape of the quadrupole to monopole ratio through non-linear
corrections to infall velocities.

</DOC>
<DOC>
<DOCNO> 100034 </DOCNO>
Matching control laws for a ball and beam system


  This note describes a method for generating an infinite-dimensional family of
nonlinear control laws for underactuated systems. For a ball and beam system,
the entire family is found explicitly.

</DOC>
<DOC>
<DOCNO> 120456 </DOCNO>
On the Determination of the He Abundance in Extragalactic H II Regions


  Of the light element abundances capable of testing standard big bang
nucleosynthesis, only He4 is measured with an accuracy of a few percent. Thus,
it is imperative to establish a comprehensive technique for determining He4
abundances and reliable estimates of the true systematic uncertainties. Helium
abundance determinations in H II regions are made from the observations of
several distinct He I emission lines and their strengths relative to H I
emission lines. With the general availability of large format, linear CCD
detectors, the accuracy of relative emission line ratios has improved to the
point where several terms in the error budget which were assumed to be
negligible may now be important. Here we investigate the estimation of errors
in deriving and reporting nebular helium abundances from optical emission line
spectra.

</DOC>
<DOC>
<DOCNO> 8389 </DOCNO>
Characterization of One-Dimensional Luttinger Liquids in Terms of


  We develop a bosonization approach to study the low temperature properties of
one-dimensional gas of particles obeying fractional exclusion statistics (FES).
It is shown that such ideal gas reproduces the low-energy excitations and
asymptotic exponents of a one-component Luttinger liquid (with no internal
degrees of freedom). The bosonized effective theory at low energy (or
temperature) is identified to a $c=1$ conformal field theory (CFT) with
compactified radius determined by the statistics parameter $\lambda$. Moreover,
this CFT can be put into a form of the harmonic fluid description for Luttinger
liquids, with the Haldane controlling parameter identified with the statistics
parameter (of quasi-particle excitations). Thus we propose to use the latter to
characterize the fixed points of 1-d Luttinger liquids. Such a characterization
is further shown to be valid for generalized ideal gas of particles with mutual
statistics in momentum space and for non-ideal gas with Luttinger-type
interactions: In either case, the low temperature behavior is controlled by an
effective statistics varying in a fixed-point line.

</DOC>
<DOC>
<DOCNO> 100796 </DOCNO>
The Painlev\'e analysis for N=2 super KdV equations


  The Painlev\'e analysis of a generic multiparameter N=2 extension of the
Korteweg-de Vries equation is presented. Unusual aspects of the analysis,
pertaining to the presence of two fermionic fields, are emphasized. For the
general class of models considered, we find that the only ones which manifestly
pass the test are precisely the four known integrable supersymmetric KdV
equations, including the SKdV$_1$ case.

</DOC>
<DOC>
<DOCNO> 120108 </DOCNO>
Morphologies and ages of star cluster pairs and multiplets in the Small


  An isophotal atlas of 75 star cluster pairs and multiplets in the Small
Magellanic Cloud is presented, comprising 176 objects. They are concentrated in
the SMC main body. The isophotal contours were made from Digitized Sky Survey
images and showed relevant structural features possibly related to interactions
in about 25% of the sample. Previous N-body simulations indicate that such
shapes could be due to tidal tails, bridges or common envelopes. The diameter
ratio between the members of a pair is preferentially in the range 1 - 2, with
a peak at 1. The projected separation is in the range ~ 3 - 22 pc with a
pronounced peak at ~ 13 pc. For 91 objects it was possible to derive ages from
Colour-Magnitude Diagrams using the OGLE-II photometric survey. The cluster
multiplets in general occur in OB stellar associations and/or HII region
complexes. This indicates a common origin and suggests that multiplets coalesce
into pairs or single clusters in a short time scale. Pairs in the SMC appear to
be mostly coeval and consequently captures are a rare phenomenon. We find
evidence that star cluster pairs and multiplets may have had an important role
in the dynamical history of clusters presently seen as large single objects.

</DOC>
<DOC>
<DOCNO> 151075 </DOCNO>
A Yang-Mills Theory in Loop Space and Generalized Chapline-Manton


  We consider a Yang-Mills theory in loop space with an affine Lie gauge group.
The Chapline-Manton coupling, the coupling between Yang-Mills fields and an
abelian antisymmetric tensor field of second rank via the Chern-Simons term, is
systematically derived within the framework of the Yang-Mills theory. The
generalized Chapline-Manton couplings, the couplings among non-abelian tensor
fields of second rank, Yang-Mills fields, and an abelian tensor field of third
rank, are also derived by applying the non-linear realization method to the
Yang-Mills theory. These couplings are accompanied by {\it BF}-like terms.

</DOC>
<DOC>
<DOCNO> 12473 </DOCNO>
Quantum-efficient charge detection using a single-electron transistor


  We evaluate the detector nonideality (and energy sensitivity) of a
normal-state single-electron transistor (SET) in the cotunneling regime in a
two-charge-state approximation. For small conductances and at zero temperature,
the SET's performance as a charge-qubit readout device is characterized by a
universal one-parameter function. The result shows that near-ideal,
quantum-limited measurement is possible for a wide range of small bias
voltages. However, near the threshold voltage for crossover to sequential
tunneling, the device becomes strongly nonideal. The (symmetrized)
current-charge cross-correlation vanishes for low frequencies, causing two
different definitions of detector nonideality to agree. Interpretations of
these findings are discussed.

</DOC>
<DOC>
<DOCNO> 40098 </DOCNO>
HiX2000: Theory Summary


  We summarize the theoretical consensus of the HiX workshop concerning those
measurements which seem most appropriate for inclusion in the ``white paper''
being prepared to justify the proposed 12 GeV upgrade at Jefferson Lab. The
criteria for inclusion are that such measurements should be decisive, not
possible elsewhere and should answer crucial physics questions with broad
implications.

</DOC>
<DOC>
<DOCNO> 116786 </DOCNO>
How high the temperature of a liquid be raised without boiling?


  How high the temperature of a liquid be raised beyond its boiling point
without vaporizing (known as the limit of superheat) is an interesting subject
of investigation. A new method of finding the limit of superheat of liquids is
presented here. The superheated liquids are taken in the form of drops
suspended in visco elastic gel. The nucleation is detected acoustically by a
sensitive piezo-electric transducer, coupled to a multi channel scaler and the
nucleation is observed as a funtion of time and with increase of temperature.
The limit of superheat measured by the present method supersedes all other
measurements and theoretical predictions in reaching closest to the critical
temperature and warrants improved theoretical predictions.

</DOC>
<DOC>
<DOCNO> 85265 </DOCNO>
The Relation Between Technique of Conformal Flat and


  The relation between the technique of conformal flat and
Damour-Ruffini-Zhao's method is investigated in this paper. It is pointed out
that the two methods give the same results when the metric has the form
$g_{\alpha\beta=0},$ with $\alpha=0,1$ and $\beta=2,3$. It is indicated that
the two methods are not equivalent for general case.

</DOC>
<DOC>
<DOCNO> 99823 </DOCNO>
Ensembles d'unicite pour les polynomes (Sets of Uniqueness for


  Let E be a compact set of C of positive logarithmic capacity. Let us suppose
that for every polynomial $P\not=id$ we have $P^{-1}(E)\not=E$. Then for all no
constant polynomials f and g such that $f^{-1}(E)=g^{-1}(E)$ we have f=g.

</DOC>
<DOC>
<DOCNO> 13147 </DOCNO>
Strong coupling Hartree-Fock approximation in the dynamical mean-field


  In the limit of infinite spatial dimensions a thermodynamically consistent
theory, which is valid for arbitrary value of the Coulombic interaction
($U<\infty$), is built for the Hubbard model when the total auxiliary
single-site problem exactly splits into four subspaces with different ``vacuum
states''. Some analytical results are given for the Hartree-Fock approximation
when the 4-pole structure for Green's function is obtained: two poles describe
contribution from the Fermi liquid component, which is ferromagnetic and
dominant for small electron and hole concentrations (``overdoped case'' of
high-$T_c$'s), whereas other two describe contribution from the non-Fermi
liquid, which is antiferromagnetic and dominant close to half filling
(``underdoped case'').

</DOC>
<DOC>
<DOCNO> 122626 </DOCNO>
Eclipsing Broad Emission Lines in Hercules X-1: Evidence for a Disk


  We present disk wind model calculations for the broad emission lines seen in
the ultraviolet spectra of the X-ray binary Hercules X-1. Recent HST/STIS
observations of these lines suggest that they are kinematically linked to the
orbital motion of the neutron star and exhibit a red-shifted to blue-shifted
evolution of the line shape during the progression of the eclipse from ingress
to egress which is indicative of disk emission. Furthermore, these lines are
single-peaked which implies that they may be formed in a disk wind similar to
those we have proposed as producing the broad emission lines seen in the UV
spectra of active galactic nuclei. We compute line profiles as a function of
eclipse phase and compare them to the observed line profiles. Various effects
may modify the appearance of the lines including resonant scattering in the
wind itself, self-shadowing of the warped disk from the central continuum, and
self-obscuration of parts of the disk along the observer's line-of-sight. These
latter two effects can cause orbital and precessional phase dependent
variations in the emission lines. Hence, examination of the line profiles as a
function of these phases can, in principle, provide additional information on
the characteristics of the disk warp.

</DOC>
<DOC>
<DOCNO> 13233 </DOCNO>
Towards identifying the world stock market cross-correlations: DAX


  Effects connected with the world globalization affect also the financial
markets. On a way towards quantifying the related characteristics we study the
financial empirical correlation matrix of the 60 companies which both the
Deutsche Aktienindex (DAX) and the Dow Jones (DJ) industrial average comprised
during the years 1990-1999. The time-dependence of the underlying
cross-correlations is monitored using a time window of 60 trading days. Our
study shows that if the time-zone delays are properly accounted for the two
distant markets largely merge into one. This effect is particularly visible
during the last few years. It is however the Dow Jones which dictates the
trend.

</DOC>
<DOC>
<DOCNO> 118168 </DOCNO>
The Formation History of Globular Clusters


  The properties of old globular cluster systems in galaxy halos are used to
infer quantitative constraints on aspects of generic star (cluster) formation.
First, the spatial distribution of globulars in three large galaxies, together
with trends in total cluster population vs. galaxy luminosity for 97 early-type
systems plus the halo of the Milky Way, imply that bound stellar clusters
formed with a universal efficiency throughout early protogalaxies: by mass,
always 0.26% of star-forming gas was converted into globulars rather than halo
field stars. That this fraction is so robust in the face of extreme variations
in local and global galaxy environment suggests that any parcel of gas needs
primarily to exceed a relative density threshold in order to form a bound
cluster of stars. Second, it is shown that a strict, empirical scaling of total
binding energy with luminosity and Galactocentric position is a defining
equation for a fundamental plane of Galactic globular clusters. The
characteristics of this plane, which subsumes all other observable correlations
between the structural parameters of globulars, provide a small but complete
set of facts that must be explained by theories of cluster formation and
evolution in the Milky Way. It is suggested that the E_b(L,r_{\rm gc}) relation
specifically resulted from star formation efficiencies having been
systematically higher inside more massive protoglobular gas clumps.

</DOC>
<DOC>
<DOCNO> 121182 </DOCNO>
Entropic-Acoustic instability in shocked accretion flows


  A new instability mechanism is described in accretion flows where the gas is
accelerated from a stationary shock to a sonic surface. The instability is
based on a cycle of acoustic and entropic waves in this subsonic region of the
flow. When advected adiabatically inward, entropy perturbations trigger
acoustic waves propagating outward. If a shock is present at the outer
boundary, acoustic waves reaching the shock produce new entropy perturbations,
thus creating an entropic-acoustic cycle between the shock and the sonic
surface. The interplay of acoustic and entropy perturbations is estimated
analytically using a simplified model based on the compact nozzle
approximation. According to this model, the entropic-acoustic cycle is unstable
if the sound speed at the sonic surface significantly exceeds the sound speed
immediately after the shock. The growth rate scales like the inverse of the
advection time from the outer shock to the sonic point. The frequency of the
most unstable perturbations is comparable to the refraction cutoff, defined as
the frequency below which acoustic waves propagating inward are significantly
refracted outward. This generic mechanism should occur in Bondi-Hoyle-Lyttleton
accretion, and also in shocked accretion discs.

</DOC>
<DOC>
<DOCNO> 8545 </DOCNO>
A Possible Crypto-Superconducting Structure in a Superconducting


  We have measured the dc and ac electrical and magnetic properties in various
magnetic fields of the recently reported superconducting ferromagnet
RuSr2GdCu2O8. Our reversible magnetization measurements demonstrate the absence
of a bulk Meissner state in the compound below the superconducting transition
temperature. Several scenarios that might account for the absence of a bulk
Meissner state, including the possible presence of a sponge-like non-uniform
superconducting or a crypto-superconducting structure in the chemically uniform
Ru-1212, have been proposed and discussed.

</DOC>
<DOC>
<DOCNO> 84903 </DOCNO>
General relativity as a complete theory and its new consequences


  It is shown that a local extension of distances in a gravitational field
leads to a global topological difference between the Schwarzschild coordinates
and the physical coordinates of local inertial frame. In term of a physical
time and a physical radius the falling in Schwarzschild field particles and
photons elastically reflect from a gravitational radius. It is shown that the
Schwarzschild frame is complete, an interior region of gravitational radius is
unphysical, a horizon and a singularity not appear. As result the general
relativity really predicts an existence of heavy barionic and quark stars and
quasars instead of black holes. The high redshifts of quasars can be explained
mainly as a gravitational redshift. A model of oscillating Universe without a
cosmological singularity is proposed. A new type of cosmological redshift is
predicted which can partly solve the dark matter problem. In the theories of
strings and branes the singularities of black hole solutions disappear in term
of physical variables. A renormalization in quantum field theory also is
derived as a natural consequence of general relativity prescriptions.

</DOC>
<DOC>
<DOCNO> 151127 </DOCNO>
Light-cone formulation and spin spectra of massive strings


  It is shown that all bosonic and fermionic massive string models admit
consistent light-cone formulations. This result is used to derive the spin
generating functions of these models in four dimensions.

</DOC>
<DOC>
<DOCNO> 83044 </DOCNO>
Recognition Performance of a Structured Language Model


  A new language model for speech recognition inspired by linguistic analysis
is presented. The model develops hidden hierarchical structure incrementally
and uses it to extract meaningful information from the word history - thus
enabling the use of extended distance dependencies - in an attempt to
complement the locality of currently used trigram models. The structured
language model, its probabilistic parameterization and performance in a
two-pass speech recognizer are presented. Experiments on the SWITCHBOARD corpus
show an improvement in both perplexity and word error rate over conventional
trigram models.

</DOC>
<DOC>
<DOCNO> 100877 </DOCNO>
On the transcendence degree of the differential field generated by


  It is a classical fact that the elliptic modular functions satisfies an
algebraic differential equation of order 3, and none of lower order. We show
how this generalizes to Siegel modular functions of arbitrary degree. The key
idea is that the partial differential equations they satisfy are governed by
Gauss--Manin connections, whose monodromy groups are well-known. Modular theta
functions provide a concrete interpretation of our result, and we study their
differential properties in detail in the case of degree 2.

</DOC>
<DOC>
<DOCNO> 100999 </DOCNO>
Variations on the theme of Marcinkiewicz' inequality


  We present a new approach to the Marcinkiewicz interpolation inequality for
the distribution function of the Hilbert transform, and prove an "abstract"
version of this inequality. The approach uses "logarithmic determinants" and
new estimates of canonical products of genus one.

</DOC>
<DOC>
<DOCNO> 72070 </DOCNO>
(Dis)continuities of Massless Limits in Spin 3/2-mediated Interactions


  We extend to its spin~3/2 supersymmetric partner the very recent
demonstration that the massless limit of massive spin~2 exchange amplitudes can
be made continuous in background AdS spaces, in contrast to the known flat
space discontinuities for both systems. In an AdS background, unlike spin~2
where the limit m\to0 is the massless one, spin~3/2 ``masslessness'' requires
m\to\sqrt{-\Lambda/3}, the supergravity value tuning the mass and cosmological
constant that uniquely provides gauge invariance and two helicities. We find
that continuity of the spin~3/2--mediated exchange amplitude can be regained in
two ``massless'' limits m\to0 and m\to\sqrt{-\Lambda/3}; only the latter
corresponds to cosmological supergravity.

</DOC>
<DOC>
<DOCNO> 10361 </DOCNO>
Renormalization of pinned elastic systems: how does it work beyond one


  We study the field theories for pinned elastic systems at equilibrium and at
depinning. Their $\beta$-functions differ to two loops by novel ``anomalous''
terms. At equilibrium we find a roughness $\zeta=0.20829804 \epsilon + 0.006858
\epsilon^2$ (random bond), $\zeta=\epsilon/3$ (random field). At depinning we
prove two-loop renormalizability and that random field attracts shorter range
disorder. We find $\zeta=\frac{\epsilon}{3}(1 + 0.14331 \epsilon)$,
$\epsilon=4-d$, in violation of the conjecture $\zeta=\epsilon/3$, solving the
discrepancy with simulations. For long range elasticity
$\zeta=\frac{\epsilon}{3}(1 + 0.39735 \epsilon)$, $\epsilon=2-d$, much closer
to the experimental value ($\approx 0.5$ both for liquid helium contact line
depinning and slow crack fronts) than the standard prediction 1/3.

</DOC>
<DOC>
<DOCNO> 13064 </DOCNO>
Structure factors for the simplest solvable model of polydisperse


  Closed analytical expressions for scattering intensity and other global
structure factors are derived for a new solvable model of polydisperse sticky
hard spheres. The starting point is the exact solution of the ``mean spherical
approximation'' for hard core plus Yukawa potentials, in the limit of infinite
amplitude and vanishing range of the attractive tail, with their product
remaining constant. The choice of factorizable coupling (stickiness) parameters
in the Yukawa term yields a simpler ``dyadic structure'' in the Fourier
transform of the Baxter factor correlation function $q_{ij}(r)$, with a
remarkable simplification in all structure functions with respect to previous
works. The effect of size and stickiness polydispersity is analyzed and
numerical results are presented for two particular versions of the model: i)
when all polydisperse particles have a single, size-independent, stickiness
parameter, and ii) when the stickiness parameters are proportional to the
diameters. The existence of two different regimes for the average structure
factor, respectively above and below a generalized Boyle temperature which
depends on size polydispersity, is recognized and discussed. Because of its
analycity and simplicity, the model may be useful in the interpretation of
small-angle scattering experimental data for polydisperse colloidal fluids of
neutral particles with surface adhesion.

</DOC>
<DOC>
<DOCNO> 7623 </DOCNO>
Relaxation processes in harmonic glasses?


  A relaxation process, with the associated phenomenology of sound attenuation
and sound velocity dispersion, is found in a simulated harmonic Lennard-Jones
glass. We propose to identify this process with the so called microscopic (or
instantaneous) relaxation process observed in real glasses and supercooled
liquids. A model based on the memory function approach accounts for the
observation, and allows to relate to each others: 1) the characteristic time
and strength of this process, 2) the low frequency limit of the dynamic
structure factor of the glass, and 3) the high frequency sound attenuation
coefficient, with its observed quadratic dependence on the momentum transfer.

</DOC>
<DOC>
<DOCNO> 121456 </DOCNO>
Reverberation Measurements of Quasars and the Size-Mass-Luminosity


  A 7.5 years spectrophotometric monitoring program of 28 Palomar-Green quasars
to determine the size of their broad emission line region (BLR) is reviewed. We
find both the continuum and the emission line fluxes of all quasars to vary
during this period. Seventeen objects has adequate sampling for reverberation
mapping and in all of them we find the Balmer line variations to lag those of
the continuum by ~100 days. This study increases the available luminosity range
for studying the size-mass-luminosity relations in active galactic nuclei
(AGNs) by two orders of magnitude and doubles the number of objects suitable
for such studies. Combining our results with data available for Seyfert 1
galaxies, we find the BLR size to scale with the rest-frame 5100 A luminosity
as L^{0.70 +/- 0.03}. This result is different from previous studies, and
suggests that the effective ionization parameter in AGNs may be a decreasing
function of luminosity. We are also able to constrain, subject to the
assumption that gravity dominates the motions of the BLR gas, the scaling
relation between the mass of the central black hole and the AGN's luminosity.
We find that the central mass scales with the 5100 A luminosity as
M\proptoL^{0.5 +/- 0.1}.
  A program to monitor 11 high-luminosity quasars is presented here for the
first time. Preliminary results from this program indicate continuum variation
of order of 0.1 mag in all objects. We illustrate the importance and
feasibility of monitoring those objects spectrophotometrically. When this
program will be completed reverberation mapping studies will cover the entire
AGNs luminosity range from 10^{41} to 10^{48} ergs/s.

</DOC>
<DOC>
<DOCNO> 7697 </DOCNO>
Constructive Fractional-Moment Criteria for Localization in Random


  We present a family of finite-volume criteria which cover the regime of
exponential decay for the fractional moments of Green functions of operators
with random potentials. Such decay is a technically convenient characterization
of localization for it is known to imply spectral localization, absence of
level repulsion, dynamical localization and a related condition which plays a
significant role in the quantization of the Hall conductance in two-dimensional
Fermi gases. The constructive criteria also preclude fast power-law decay of
the Green functions at mobility edges.

</DOC>
<DOC>
<DOCNO> 121819 </DOCNO>
Nature and Nurture: a model for soft gamma-ray repeaters


  During supernova explosions, strange stars with almost bare quark surfaces
may be formed. Under certain conditions, these stars could be rapidly spun down
by the torque exerted by the fossil disks formed from the fall-back materials.
They may also receive large kicks and hence, have large proper motion
velocities. When these strange stars pass through the spherical ``Oort'' comet
cloud formed during the pre-supernova era, they will capture some small-scale
comet clouds and collide with some comet-like objects occasionally. These
impacts can account for the repeating bursts as observed from the soft gamma
repeaters (SGRs). According to this picture, it is expected that SGR 1900+14
will become active again during 2004-2005.

</DOC>
<DOC>
<DOCNO> 11867 </DOCNO>
Circular photogalvanic effect induced by monopolar spin orientation in


  The circular photogalvanic effect (CPGE) has been observed in (100)-oriented
$p$-GaAs/AlGaAs quantum wells at normal incidence of far-infrared radiation. It
is shown that monopolar optical spin orientation of free carriers causes an
electric current which reverses its direction upon changing from left to right
circularly polarized radiation. CPGE at normal incidence and the occurence of
the linear photogalvanic effect indicate a reduced point symmetry of studied
multi-layered heterostructures. As proposed, CPGE can be utilized to
investigate separately spin polarization of electrons and holes and the
symmetry of quantum wells.

</DOC>
<DOC>
<DOCNO> 40089 </DOCNO>
New limit for nu_(e)->nu_(tau) oscillations


  We present a calculation for a new limit on nu_(e)->nu_(tau) oscillations
based on the recent data from CHORUS experiment

</DOC>
<DOC>
<DOCNO> 67834 </DOCNO>
One-Particle Inclusive B sub s -> D bar sub s X Decays


  We discuss one-particle inclusive B sub s -> D bar sub s X decays using a QCD
based method already applied to B -> D bar X. A link between the right charm
non-perturbative form factors of the semi-leptonic decays and those of the
non-leptonic decays is established. Our results are compatible with current
experimental knowledge.

</DOC>
<DOC>
<DOCNO> 170763 </DOCNO>
Quantum scattering in one dimension


  A self-contained discussion of nonrelativistic quantum scattering is
presented in the case of central potentials in one space dimension, which will
facilitate the understanding of the more complex scattering theory in two and
three dimensions. The present discussion illustrates in a simple way the
concept of partial-wave decomposition, phase shift, optical theorem and
effective-range expansion.

</DOC>
<DOC>
<DOCNO> 152463 </DOCNO>
W Algebras from AdS/CFT Correspondence


  We consider a system of D5/D1 branes in the supergravity background
AdS_3xS^3xX, where X is T^4 or K3. By investigating the structure of the
missing states in the conformal description, we are able to extend the AdS/CFT
correspondence to W algebras. As a test of this new formulation the results are
compared to Hilbert schemes and more general supergravity backgrounds as
deformations by D3-branes or six-dimensional Calabi-Yau manifolds.

</DOC>
<DOC>
<DOCNO> 72046 </DOCNO>
Testing CPT invariance by using C-even neutral-meson--antimeson


  We consider the decays of a correlated neutral-meson--antimeson state with
C-parity +1. We show that there is CPT noninvariance in the mixing of the
neutral mesons if, for any two decay modes f and g, the decay rate has a
component R_A which is antisymmetric under the interchange of the decay times
t_1 and t_2. In particular, one may cleanly extract the CPT-noninvariance
parameter with the help of R_A by using opposite-sign dilepton events.

</DOC>
<DOC>
<DOCNO> 100844 </DOCNO>
Twistor quotients of hyperkaehler manifolds


  We generalize the hyperkaehler quotient construction to the situation where
there is no group action preserving the hyperkaehler structure but for each
complex structure there is an action of a complex group preserving the
corresponding complex symplectic structure. Many (known and new) hyperkaehler
manifolds arise as quotients in this setting. For example, all hyperkaehler
structures on semisimple coadjoint orbits of a complex semisimple Lie group $G$
arise as such quotients of $T^*G$. The generalized Legendre transform
construction of Lindstroem and Rocek is also explained in this framework.

</DOC>
<DOC>
<DOCNO> 84125 </DOCNO>
Regular coordinate systems for Schwarzschild and other spherical


  The continuation of the Schwarzschild metric across the event horizon is
almost always (in textbooks) carried out using the Kruskal-Szekeres
coordinates, in terms of which the areal radius r is defined only implicitly.
We argue that from a pedagogical point of view, using these coordinates comes
with several drawbacks, and we advocate the use of simpler, but equally
effective, coordinate systems. One such system, introduced by Painleve and
Gullstrand in the 1920's, is especially simple and pedagogically powerful; it
is, however, still poorly known today. One of our purposes here is therefore to
popularize these coordinates. Our other purpose is to provide generalizations
to the Painleve-Gullstrand coordinates, first within the specific context of
Schwarzschild spacetime, and then in the context of more general spherical
spacetimes.

</DOC>
<DOC>
<DOCNO> 169886 </DOCNO>
Quantum state protection using all-optical feedback


  An all-optical feedback scheme in which the output of a cavity mode is used
to influence the dynamics of another cavity mode is considered. We show that
under ideal conditions, perfect preservation against decoherence of a generic
quantum state of the source mode can be achieved.

</DOC>
<DOC>
<DOCNO> 85468 </DOCNO>
Hairy Black Holes, Horizon Mass and Solitons


  Properties of the horizon mass of hairy black holes are discussed with
emphasis on certain subtle and initially unexpected features. A key property
suggests that hairy black holes may be regarded as `bound states' of ordinary
black holes without hair and colored solitons. This model is then used to
predict the qualitative behavior of the horizon properties of hairy black
holes, to provide a physical `explanation' of their instability and to put
qualitative constraints on the end point configurations that result from this
instability. The available numerical calculations support these predictions.
Furthermore, the physical arguments are robust and should be applicable also in
more complicated situations where detailed numerical work is yet to be carried
out.

</DOC>
<DOC>
<DOCNO> 9393 </DOCNO>
Evidence for an energy scale for quasiparticle dispersion in


  Quasiparticle dispersion in $Bi_{2}Sr_{2}CaCu_{2}O_{8}$ is investigated with
improved angular resolution as a function of temperature and doping. Unlike the
linear dispersion predicted by the band calculation, the data show a sharp
break in dispersion at $50\pm10$ $meV$ binding energy where the velocity
changes by a factor of two or more. This change provides an energy scale in the
quasiparticle self-energy. This break in dispersion is evident at and away from
the d-wave node line, but the magnitude of the dispersion change decreases with
temperature and with increasing doping.

</DOC>
<DOC>
<DOCNO> 8229 </DOCNO>
Randomly dilute spin models: a six-loop field-theoretic study


  We consider the Ginzburg-Landau MN-model that describes M N-vector cubic
models with O(M)-symmetric couplings. We compute the renormalization-group
functions to six-loop order in d=3. We focus on the limit N -> 0 which
describes the critical behaviour of an M-vector model in the presence of weak
quenched disorder. We perform a detailed analysis of the perturbative series
for the random Ising model (M=1). We obtain for the critical exponents: gamma =
1.330(17), nu = 0.678(10), eta = 0.030(3), alpha=-0.034(30), beta = 0.349(5),
omega = 0.25(10). For M > 1 we show that the O(M) fixed point is stable, in
agreement with general non-perturbative arguments, and that no random fixed
point exists.

</DOC>
<DOC>
<DOCNO> 101025 </DOCNO>
Cartan-decomposition subgroups of SU(2,n)


  We give explicit, practical conditions that determine whether or not a
closed, connected subgroup H of G = SU(2,n) has the property that there exists
a compact subset C of G with CHC = G. To do this, we fix a Cartan decomposition
G = K A K of G, and then carry out an approximate calculation of the
intersection of KHK with A, for each closed, connected subgroup H of G. This
generalizes the work of Hee Oh and Dave Witte for G = SO(2,n).

</DOC>
<DOC>
<DOCNO> 84211 </DOCNO>
Renormalization group improved black hole spacetimes


  We study the quantum gravitational effects in spherically symmetric black
hole spacetimes. The effective quantum spacetime felt by a point-like test mass
is constructed by ``renormalization group improving'' the Schwarzschild metric.
The key ingredient is the running Newton constant which is obtained from the
exact evolution equation for the effective average action. The conformal
structure of the quantum spacetime depends on its ADM-mass M and it is similar
to that of the classical Reissner-Nordstrom black hole. For M larger than,
equal to, and smaller than a certain critical mass $M_{\rm cr}$ the spacetime
has two, one and no horizon(s), respectively. Its Hawking temperature, specific
heat capacity and entropy are computed as a function of M. It is argued that
the black hole evaporation stops when M approaches $M_{\rm cr}$ which is of the
order of the Planck mass. In this manner a ``cold'' soliton-like remnant with
the near-horizon geometry of $AdS_2\times S^2$ is formed. As a consequence of
the quantum effects, the classical singularity at r=0 is either removed
completely or it is at least much milder than classically; in the first case
the quantum spacetime has a smooth de Sitter core which would be in accord with
the cosmic censorship hypothesis even if $M<M_{\rm cr}$.

</DOC>
<DOC>
<DOCNO> 116557 </DOCNO>
An inertial range length scale in structure functions


  It is shown using experimental and numerical data that within the traditional
inertial subrange defined by where the third order structure function is linear
that the higher order structure function scaling exponents for longitudinal and
transverse structure functions converge only over larger scales, $r>r_S$, where
$r_S$ has scaling intermediate between $\eta$ and $\lambda$ as a function of
$R_\lambda$. Below these scales, scaling exponents cannot be determined for any
of the structure functions without resorting to procedures such as extended
self-similarity (ESS). With ESS, different longitudinal and transverse higher
order exponents are obtained that are consistent with earlier results. The
relationship of these statistics to derivative and pressure statistics, to
turbulent structures and to length scales is discussed.

</DOC>
<DOC>
<DOCNO> 71663 </DOCNO>
The decay b -> s g at NLL in the Standard Model


  I present the Standard Model calculation of the decay rate for b -> s g (g
denotes a gluon) at next-to-leading logarithms (NLL). In order to get a
meaningful physical result, the decay b -> s g g and certain contributions of b
-> s \bar{f} f (where f are the light quark flavours u, d and s) have to be
included as well. Numerically we get BR^(NLL) = (5.0 +/- 1.0) * 10^{-3} which
is more than a factor 2 larger than the leading logarithmic result BR^(LL) =
(2.2 +/- 0.8) * 10^{-3}. Further, I consider the impact of this contribution on
the charmless hadronic branching ratio BRc, which could be used to extract the
CKM-ratio |V_(ub)/V_(cb)| with more accuracy. Finally, I have a short look at
BRc in scenarios where the Wilson coefficient C_8 is enhanced by new physics.

</DOC>
<DOC>
<DOCNO> 71751 </DOCNO>
Probing Z' gauge boson with the spin configuration of top quark pair


  We explore the effects of extra neutral gauge boson involved in the
supersymmetric E6 model on the spin configuration of the top quark pair
produced at the polarized e- e+ collider. Generic mixing terms are considered
including kinetic mixing terms as well as mass mixing. In the off-diagonal spin
basis of the standard model, we show that the cross sections for the suppressed
spin configurations can be enhanced with the effects of the Z' boson through
the modification of the spin configuration of produced top quark pair enough to
be measured in the Linear Colliders, which provides the way to observe the
effects of Z' boson and discriminate the pattern of gauge group decomposition.
It is pointed out that the kinetic mixing may dilute the effects of mass mixing
terms, and we have to perform the combined analysis.

</DOC>
<DOC>
<DOCNO> 83370 </DOCNO>
Complexity analysis for algorithmically simple strings


  Given a reference computer, Kolmogorov complexity is a well defined function
on all binary strings. In the standard approach, however, only the asymptotic
properties of such functions are considered because they do not depend on the
reference computer. We argue that this approach can be more useful if it is
refined to include an important practical case of simple binary strings.
Kolmogorov complexity calculus may be developed for this case if we restrict
the class of available reference computers. The interesting problem is to
define a class of computers which is restricted in a {\it natural} way modeling
the real-life situation where only a limited class of computers is physically
available to us. We give an example of what such a natural restriction might
look like mathematically, and show that under such restrictions some error
terms, even logarithmic in complexity, can disappear from the standard
complexity calculus.
  Keywords: Kolmogorov complexity; Algorithmic information theory.

</DOC>
<DOC>
<DOCNO> 70055 </DOCNO>
No Primordial Magnetic Field from Domain Walls


  It is pointed out that, contrary to some claims in the literature, the domain
walls cannot be a source of a correlated at large scales primordial magnetic
field, even if the fermionic modes bound on the wall had ferromagnetic
properties. In a particular model with massive (2+1) dimensional fermions bound
to a domain wall, previously claimed to exhibit a ferromagnetic behavior, it is
explicitly shown that the fermionic system in fact has properties of a normal
diamagnetic with the susceptibility vanishing at high temperature.

</DOC>
<DOC>
<DOCNO> 72061 </DOCNO>
Probing the dark energy: methods and strategies


  The presence of dark energy in the Universe is inferred directly from the
accelerated expansion of the Universe, and indirectly, from measurements of
cosmic microwave background (CMB) anisotropy. Dark energy contributes about 2/3
of the critical density, is very smoothly distributed, and has large negative
pressure. Its nature is very much unknown. Most of its discernible consequences
follow from its effect on evolution of the expansion rate of the Universe,
which in turn affects the growth of density perturbations and the age of the
Universe, and can be probed by the classical kinematic cosmological tests.
Absent a compelling theoretical model (or even a class of models), we describe
the dark energy by an effective equation-of-state w=p_X/\rho_X which is allowed
to vary with time. We describe and compare different approaches for determining
w(t), including magnitude-redshift (Hubble) diagram, number counts of galaxies
and clusters, and CMB anisotropy, focusing particular attention on the use of a
sample of several thousand type Ia supernova with redshifts z\lesssim 1.7, as
might be gathered by the proposed SNAP satellite. Among other things, we derive
optimal strategies for constraining cosmological parameters using type Ia
supernovae. While in the near term CMB anisotropy will provide the first
measurements of w, supernovae and number counts appear to have the most
potential to probe dark energy.

</DOC>
<DOC>
<DOCNO> 13574 </DOCNO>
Coordinate Representation of the Two-Spinon wavefunction and Spinon


  By deriving and studying the coordinate representation for the two-spinon
wavefunction, we show that spinon excitations in the Haldane-Shastry model
interact. The interaction is given by a short-range attraction and causes a
resonant enhancement in the two-spinon wavefunction at short separations
between the spinons. We express the spin susceptibility for a finite lattice in
terms of the resonant enhancement, given by the two-spinon wavefunction at zero
separation. In the thermodynamic limit, the spinon attraction turns into the
square-root divergence in the dynamical spin susceptibility.

</DOC>
<DOC>
<DOCNO> 8702 </DOCNO>
Polariton Dispersion Law in Periodic Bragg and Near-Bragg Multiple


  The structure of polariton spectrum is analyzed for periodic multiple quantum
well structures with periods at or close to Bragg resonance condition at the
wavelength of the exciton resonance. The results obtained used to discuss
recent reflection and luminescent experiments by M. H\"{u}bner et al [Phys.
Rev. Lett. {\bf 83}, 2841 (1999)] carried out with long multiple quantum well
structures. It is argued that the discussion of quantum well structures with
large number of wells is more appropriate in terms of normal modes of infinite
periodic structures rather then in terms of super- and sub- radiant modes.

</DOC>
<DOC>
<DOCNO> 150678 </DOCNO>
Twisted Bundle on Noncommutative Space and U(1) Instanton


  We study the notion of twisted bundles on noncommutative space. Due to the
existence of projective operators in the algebra of functions on the
noncommutative space, there are twisted bundles with non-constant dimension.
The U(1) instanton solution of Nekrasov and Schwarz is such an example. As a
mathematical motivation for not excluding such bundles, we find gauge
transformations by which a bundle with constant dimension can be equivalent to
a bundle with non-constant dimension.

</DOC>
<DOC>
<DOCNO> 102505 </DOCNO>
Hyperbolic Cauchy problem and Leray's residue formula


  We give an algebraic description of wave fronts that appear in strictly
hyperbolic Cauchy problem. Concrete form of definig function of wave front
issued from initial algebraic variety is obtained by the aid of the Gauss-Manin
systems satisfied by Gel'fand -Leray integrals.

</DOC>
<DOC>
<DOCNO> 10901 </DOCNO>
Power law fluctuation generator based on analog electrical circuit


  We constructed an analog circuit generating fluctuations of which a
probability density function has power law tails. In the circuit fluctuations
with an arbitrary exponent of the power law can be obtained by tuning the
resistance. A theory of a differential equation with both multiplicative and
additive noises which describes the circuit is introduced. The circuit is
composed of a noise generator, an analog multiplier and an integral circuit.
Sequential outputs of the circuit are observed and their probability density
function and autocorrelation coefficients are shown. It is found that
correlation time of the autocorrelation coefficient is dependent on the power
law exponent.

</DOC>
<DOC>
<DOCNO> 12075 </DOCNO>
Dislocation-Mediated Melting: The One-Component Plasma Limit


  The melting parameter $\Gamma_m$ of a classical one-component plasma is
estimated using a relation between melting temperature, density, shear modulus,
and crystal coordination number that follows from our model of
dislocation-mediated melting. We obtain $\Gamma_m=172\pm 35,$ in good agreement
with the results of numerous Monte-Carlo calculations.

</DOC>
<DOC>
<DOCNO> 100254 </DOCNO>
Some geometric aspects of variational calculus in constrained mechanics


  We give a geometric description of variational principles in mechanics, with
special attention to constrained systems. For the general case of nonholonomic
constraints, a unified variational approach is given, and the equations of
motion of both vakonomic and nonholonomic frameworks are obtained. We study
specifically the existence of infinitesimal variations in both cases. When the
constraints are integrable, both formalisms are compared and it is proved that
they coincide. As examples, we give geometric formulations of the equations of
motion for the case of optimal control and for vakonomic and nonholonomic
mechanics with constraints linear in the velocities.

</DOC>
<DOC>
<DOCNO> 100404 </DOCNO>
Four Easy Pieces - Explicit R Matrices from the (\dot{0}_m|\alpha)


  We provide explicit presentations of members of a suite of R matrices arising
from the (\dot{0}_m|\alpha) representations of the quantum superalgebras
U_q[gl(m|1)]. Our algorithm constructs both trigonometric and quantum R
matrices; all of which are graded, in that they solve a graded Yang-Baxter
equation. This grading is easily removed, yielding R matrices that solve the
usual Yang-Baxter equation. For m>2, the computations are impracticable for a
human to perform, so we have implemented the entire process in Mathematica, and
then performed the computations for m=1,2,3 and 4.

</DOC>
<DOC>
<DOCNO> 121923 </DOCNO>
Statistical Power, the Bispectrum and the Search for Non-Gaussianity in


  We use simulated maps of the cosmic microwave background anisotropy to
quantify the ability of different statistical tests to discriminate between
Gaussian and non-Gaussian models. Despite the central limit theorem on large
angular scales, both the genus and extrema correlation are able to discriminate
between Gaussian models and a semi-analytic texture model selected as a
physically motivated non-Gaussian model. When run on the COBE 4-year CMB maps,
both tests prefer the Gaussian model. Although the bispectrum has comparable
statistical power when computed on the full sky, once a Galactic cut is imposed
on the data the bispectrum loses the ability to discriminate between models.
Off-diagonal elements of the bispectrum are comparable to the diagonal elements
for the non-Gaussian texture model and must be included to obtain maximum
statistical power.

</DOC>
<DOC>
<DOCNO> 83319 </DOCNO>
The Competitiveness of On-Line vis-a-vis Conventional Retailing: A


  Previous research has directly studied whether on-line retailing is more
competitive than conventional retail markets. The evidence from books and music
CDs is mixed. Here, I use an indirect approach to compare the competitiveness
of on-line with conventional markets. Focusing on the retail market for books,
I identify a peculiarity in the pricing of bestsellers relative to other
titles. Supposing that competitive barriers are lower in on-line retailing, I
analyze how the lower barriers would affect the relative pricing of
bestsellers. The empirical data indicates that on-line retailing is more
competitive than conventional retailing.

</DOC>
<DOC>
<DOCNO> 71589 </DOCNO>
On the APM power spectrum and the CMB anisotropy: Evidence for a phase


  Adams et al. (1997b) have noted that according to our current understanding
of the unification of fundamental interactions, there should have been phase
transitions associated with spontaneous symmetry breaking {\em during} the
inflationary era. This may have resulted in the breaking of scale-invariance of
the primordial density perturbation for brief periods. A possible such feature
was identified in the power spectrum of galaxy clustering in the APM survey at
the scale $k \sim 0.1 h$ Mpc^{-1} and it was shown that the secondary acoustic
peaks in the power spectrum of the CMB anisotropy should consequently be
suppressed. We demonstrate that this prediction is confirmed by the recent
Boomerang and Maxima observations, which favour a step-like spectral feature in
the range $k \sim (0.06-0.6)h$ Mpc^{-1}, independently of the similar previous
indication from the APM data. Such a spectral break enables an excellent fit to
both APM and CMB data with a baryon density consistent with the BBN value. It
also allows the possibility of a matter-dominated universe with zero
cosmological constant, which we show can now account for even the evolution of
the abundance of rich clusters.

</DOC>
<DOC>
<DOCNO> 169878 </DOCNO>
Calculating the relative entropy of entanglement


  We extend Vedral and Plenio's theorem (theorem 3 in Phys. Rev. A 57, 1619) to
a more general case, and obtain the relative entropy of entanglement for a
class of mixed states, this result can also follow from Rains' theorem 9 in
Phys. Rev. A 60, 179.

</DOC>
<DOC>
<DOCNO> 9030 </DOCNO>
Beyond storage capacity in a single model neuron: Continuous replica


  A single McCulloch-Pitts neuron, that is, the simple perceptron is studied,
with focus on the region beyond storage capacity. It is shown that Parisi's
hierarchical ansatz for the overlap matrix of the synaptic couplings with so
called continuous replica symmetry breaking is a solution, and as we propose it
is the exact one, to the equilibrium problem. We describe some of the most
salient features of the theory and give results about the low temperature
region. In particular, the basics of the Parisi technique and the way to
calculate thermodynamical expectation values is explained. We have numerically
extremized the replica free energy functional for some parameter settings, and
thus obtained the order parameter function, i.e., the probability distribution
of overlaps. That enabled us to evaluate the probability density of the local
stability parameter. We also performed a simulation and found a local stability
density closer to the theoretical curve than previous numerical results were.

</DOC>
<DOC>
<DOCNO> 10021 </DOCNO>
Windings of the 2D free Rouse chain


  We study long time dynamical properties of a chain of harmonically bound
Brownian particles. This chain is allowed to wander everywhere in the plane. We
show that the scaling variables for the occupation times T_j, areas A_j and
winding angles \theta_j (j=1,...,n labels the particles) take the same general
form as in the usual Brownian motion. We also compute the asymptotic joint laws
P({T_j}), P({A_j}), P({\theta_j}) and discuss the correlations occuring in
those distributions.

</DOC>
<DOC>
<DOCNO> 12538 </DOCNO>
Oscillations of Andreev states in clean ferromagnetic films


  We investigate the influence of the exchange field on the Andreev bound
states in a ferromagnetic (F) film backed on one side by a superconductor (S).
Our model accounts for diffusive reflection at the outer surface and possible
backscattering at the FS-interface. Phase shifting of the Andreev level by the
exchange field results in an oscillatory behaviour of the density of states of
F as a function of the layer thickness. We show that our results agree
quantitatively with recent experiments.

</DOC>
<DOC>
<DOCNO> 151878 </DOCNO>
Effective Tachyon Dynamics in Superstring Theory


  A recently proposed \ell=\infty field theory model of tachyon dynamics for
unstable bosonic D-branes has been shown to arise as the two-derivative
truncation of (boundary)-string field theory. Using an \ell\to \infty limit
appropriate to stable kinks we obtain a model for the tachyon dynamics on
unstable D-branes or D-brane anti-D-brane pairs of superstring theory. The
tachyon potential is a positive definite even function of the tachyon, and at
the stable global minima there is no on-shell dynamics. The kink solution
mimics nicely the properties of stable D-branes: the spectrum of the kink
consists of infinite levels starting at zero mass, with spacing double the
value of the tachyon mass-squared. It is natural to expect that this model will
arise in (boundary) superstring field theory.

</DOC>
<DOC>
<DOCNO> 10545 </DOCNO>
Fluctuations of elastic interfaces in fluids: Theory and simulation


  We study the dynamics of elastic interfaces-membranes-immersed in thermally
excited fluids. The work contains three components: the development of a
numerical method, a purely theoretical approach, and numerical simulation. In
developing a numerical method, we first discuss the dynamical coupling between
the interface and the surrounding fluids. An argument is then presented that
generalizes the single-relaxation time lattice-Boltzmann method for the
simulation of hydrodynamic interfaces to include the elastic properties of the
boundary. The implementation of the new method is outlined and it is tested by
simulating the static behavior of spherical bubbles and the dynamics of bending
waves. By means of the fluctuation-dissipation theorem we recover analytically
the equilibrium frequency power spectrum of thermally fluctuating membranes and
the correlation function of the excitations. Also, the non-equilibrium scaling
properties of the membrane roughening are deduced, leading us to formulate a
scaling law describing the interface growth, W^2(L,T)=L^3 g[t/L^(5/2)], where
W, L and T are the width of the interface, the linear size of the system and
the temperature respectively, and g is a scaling function. Finally, the
phenomenology of thermally fluctuating membranes is simulated and the frequency
power spectrum is recovered, confirming the decay of the correlation function
of the fluctuations. As a further numerical study of fluctuating elastic
interfaces, the non-equilibrium regime is reproduced by initializing the system
as an interface immersed in thermally pre-excited fluids.

</DOC>
<DOC>
<DOCNO> 178884 </DOCNO>
Molecular Collective Vibrations in the Ternary Neutronless Fission of


  Based on a recent experimental finding which may suggest the existence of a
tri-nuclear molecular structure before the cold ternary fragmentation of
$^{252}$Cf takes place, we solved the eigenvalue problem of a certain class of
vibrations which are very likely to occur in these molecules. These
oscillations are the result of the joined action of rotations of the heavier
fragments and the transversal vibrations of the lighter spherical cluster with
respect to the fission axis. In the calculation of the interaction between the
heavier fragments we took into account higher multipole deformations, including
the hexadecupole one, and introduced a repulsive nuclear part to insure the
creation of a potential pocket in which a few molecular states can be
accommodated. The possibility to observe the de-excitation of such states is
discussed in connection with the molecular life-time.

</DOC>
<DOC>
<DOCNO> 122583 </DOCNO>
The Angular Power Spectrum of EDSGC Galaxies


  We determine the angular power spectrum, C_l, of the Edinburgh/Durham
Southern Galaxy Catalog (EDSGC) and use this statistic to constrain
cosmological parameters. Our methods for determining C_l, and the parameters
that affect it are based on those developed for the analysis of cosmic
microwave background maps. We expect them to be useful for future surveys.
Assuming flat cold dark matter models with a cosmological constant (constrained
by COBE/DMR and local cluster abundances), and a scale--independent bias, b, we
find good fits to the EDSGC angular power spectrum with 1.11 < b < 2.35 and 0.2
< Omega_m < 0.55 at 95% confidence. These results are not significantly
affected by the ``integral constraint'' or extinction by interstellar dust, but
may be by our assumption of Gaussianity.

</DOC>
<DOC>
<DOCNO> 70426 </DOCNO>
An alternative: two-mixing texture for three neutrinos or three-mixing


  The alternative formulated in the title has a chance to be settled, when the
existence of the LSND effect is experimentally excluded or confirmed. The first
option, much discussed in literature, works in the case of three active
neutrinos $\nu_e, \nu_\mu, \nu_\tau$, when among their massive states $\nu_1,
\nu_2, \nu_3$ there is no direct mixing between $\nu_1$ and $\nu_3$, and the
mass hierarchy $m^2_1 < {\sim} m^2_2 \ll m^2_3$ holds. This option is
consistent with the observed deficits of solar $\nu_e$'s and atmospheric
$\nu_\mu $'s, if $\Delta m^2_{21} \leftrightarrow \Delta m^2_{\rm sol}$ and $
\Delta m^2_{32} \leftrightarrow \Delta m^2_{\rm atm}$. On the other hand, the
second option is an extension of the idea of the former to the case of four
neutrinos $\nu_s, \nu_e, \nu_\mu, \nu_\tau$ (including one sterile neutrino
$\nu_s$), when among their massive states $\nu_0, \nu_1, \nu_2, \nu_3$ there
are no direct mixings between $\nu_0$ and $nu_2$, $\nu_0$ and $\nu_3$, $\nu_1$
and $\nu_3$, and the mass hierarchy $m^2_0 < {\sim} m^2_1 \ll m^2_2 < {\sim}
m^2_3$ is now valid. Such an option, belonging to a class of textures widely
discussed in literature, may be consistent with the observed deficits of solar
$\nu_e$'s and atmospheric $\nu_\mu$'s as well as with the LSND appearance of
$\nu_e$'s in the beam of accelerator $\nu_\mu$'s, if now $\Delta m^2_{10}
\leftrightarrow \Delta m^2_{\rm sol}$, $\Delta m^2_{32} \leftrightarrow \Delta
m^2_{\rm atm}$ and $\Delta m^2_{21} \leftrightarrow \Delta m^2_{\rm LSND}$.

</DOC>
<DOC>
<DOCNO> 69827 </DOCNO>
Two Hagedorn temperatures: a larger one for mesons, a lower one for


  We show that the Hagedorn temperature obtained from experimental spectra is
larger for mesons than for baryons. Dual string models explain this behavior
asymptotically.

</DOC>
<DOC>
<DOCNO> 121940 </DOCNO>
Gravitational Lensing Statistics as a Probe of Dark Energy


  By using the comoving distance, we derive an analytic expression for the
optical depth of gravitational lensing, which depends on the redshift to the
source and the cosmological model characterized by the cosmic mass density
parameter $\Omega_m$, the dark energy density parameter $\Omega_x$ and its
equation of state $\omega_x = p_x/\rho_x$. It is shown that, the larger the
dark energy density is and the more negative its pressure is, the higher the
gravitational lensing probability is. This fact can provide an independent
constraint for dark energy.

</DOC>
<DOC>
<DOCNO> 121203 </DOCNO>
Observations of the core of the Pleiades with the Chandra X-ray


  We present results from a 36-ksec observation of the core of the Pleiades
open cluster using ACIS-I on the Chandra X-ray Observatory. We have detected 57
sources, most of which do not have previously known optical counterparts.
Follow-up photometry indicates that many of the detections are likely to be
AGNs, in accordance with extragalactic source counts, but some of the sources
may be previously undiscovered low-mass members of the Pleiades. We discuss our
dataset and our findings about X-ray emission from early-type stars as well as
very late type stars. In particular, the large X-ray fluxes, lack of
variability, and hardness ratios of the four Pleiades B6 IV -- F4 V stars
suggest a tentative conclusion that Pleiades stars in this spectral type range
are intrinsic X-ray sources rather than previously unknown binaries in which
the X-ray emission is from a late-type companion. Also the sensitivity of
Chandra allowed us to detect nonflare X-ray emission from late-M stars.

</DOC>
<DOC>
<DOCNO> 8107 </DOCNO>
Chaos in the thermodynamic limit


  We study chaos in the Hamiltonian Mean Field model (HMF), a system with many
degrees of freedom in which $N$ classical rotators are fully coupled. We review
the most important results on the dynamics and the thermodynamics of the HMF,
and in particular we focus on the chaotic properties.We study the Lyapunov
exponents and the Kolmogorov--Sinai entropy, namely their dependence on the
number of degrees of freedom and on energy density, both for the ferromagnetic
and the antiferromagnetic case.

</DOC>
<DOC>
<DOCNO> 151744 </DOCNO>
Loop integrals in three outstanding gauges: Feynman, Light-cone and


  We apply negative dimensional integration method (NDIM) to three outstanding
gauges: Feynman, light-cone and Coulomb gauges. Our aim is to show that NDIM is
a very suitable technique to deal with loop integrals, being them originated
from any gauge choice. In Feynman gauge we perform scalar two-loop four-point
massless integrals; in the light-cone gauge we calculate scalar two-loop
integrals contributing for two-point functions without any kind of
prescriptions, since NDIM can abandon such devices -- this calculation is the
first test of our prescriptionless method beyond one-loop order; finally, for
the Coulomb gauge we consider a four propagator massless loop integral, in the
split dimensional regularization context.

</DOC>
<DOC>
<DOCNO> 69255 </DOCNO>
Asymptotic Improvement of Resummation and Perturbative Predictions in


  The improvement of resummation algorithms for divergent perturbative
expansions in quantum field theory by asymptotic information about perturbative
coefficients is investigated. Various asymptotically optimized resummation
prescriptions are considered. The improvement of perturbative predictions
beyond the reexpansion of rational approximants is discussed.

</DOC>
<DOC>
<DOCNO> 68522 </DOCNO>
Infra-red fixed points in supersymmetry


  Model independent constraints on supersymmetric models emerge when certain
couplings are drawn towards their infra-red (quasi) fixed points in the course
of their renormalization group evolution. The general principles are first
reviewed and the conclusions for some recent studies of theories with R-parity
and baryon and lepton number violations are summarized.

</DOC>
<DOC>
<DOCNO> 121686 </DOCNO>
Distribution and Kinematics of Molecular Gas in Barred Spiral Galaxies.


  We present the results of the CO mapping observations of the barred spiral
galaxy NGC3504 with the Nobeyama 45-m telescope. The distribution of the
molecular gas shows offset ridges which correspond to the distribution of HII
regions along the bar. The velocity perpendicular to the bar decreases abruptly
at the ridge. The velocity change implies that the molecular gas changes the
direction of its motion to parallel to the bar at the ridge. Since the position
angle of the major axis of the bar and the line of nodes are almost the same in
NGC 3504, an upper limit to the pattern speed of the bar can be derived
directly from the radial velocity. The resultant upper limit is 41 km/s/kpc
which is much smaller than that derived with an assumption that the corotation
radius is located at the end of the bar (77 km/s/kpc). The corotaion radius
derived from our upper limit is more than two times larger than the length of
the semi-major axis of the bar in NGC 3504.

</DOC>
<DOC>
<DOCNO> 102642 </DOCNO>
General approach to potentials with two known levels


  We present the general form of potentials with two given energy levels
$E_{1}$, $E_{2}$ and find corresponding wave functions. These entities are
expressed in terms of one function $\xi (x)$ and one parameter $\Delta
E=E_{2}$-$E_{1}$. We show how the quantum numbers of both levels depend on
properties of the function $\xi (x)$. Our approach does not need resorting to
the technique of supersymmetric (SUSY) quantum mechanics but automatically
generates both the potential and superpotential.

</DOC>
<DOC>
<DOCNO> 118587 </DOCNO>
The Northern ROSAT All-Sky (NORAS) Galaxy Cluster Survey I: X-ray


  In the construction of an X-ray selected sample of galaxy clusters for
cosmological studies, we have assembled a sample of 495 X-ray sources found to
show extended X-ray emission in the first processing of the ROSAT All-Sky
Survey. The sample covers the celestial region with declination $\delta \ge
0\deg $ and galactic latitude $|b_{II}| \ge 20\deg $ and comprises sources with
a count rate $\ge 0.06$ counts s$^{-1}$ and a source extent likelihood of 7. In
an optical follow-up identification program we find 378 (76%) of these sources
to be clusters of galaxies. ...

</DOC>
<DOC>
<DOCNO> 10258 </DOCNO>
Asymptotic step profiles from a nonlinear growth equation for vicinal


  We study a recently proposed nonlinear evolution equation describing the
collective step meander on a vicinal surface subject to the Bales-Zangwill
growth instability [O. Pierre-Louis et al., Phys. Rev. Lett. (80), 4221
(1998)]. A careful numerical analysis shows that the dynamically selected step
profile consists of sloped segments, given by an inverse error function and
steepening as sqrt(t), which are matched to pieces of a stationary
(time-independent) solution describing the maxima and minima. The effect of
smoothening by step edge diffusion is included heuristically, and a
one-parameter family of evolution equations is introduced which contains
relaxation by step edge diffusion and by attachment-detachment as special
cases. The question of the persistence of an initially imposed meander
wavelength is investigated in relation to recent experiments.

</DOC>
<DOC>
<DOCNO> 101390 </DOCNO>
Implementation of the Prelle-Singer Method for 1ODEs


  A set of MapleV R5 software routines for solving first order ordinary
differential equations (1ODEs) is presented. The package implements the
Prelle-Singer Method in its original form plus its extension to include
elementary functions (ELFs) on the integrating factor . The package also
presents a theoretical extension to deal with all 1ODEs presenting liouvillian
solutions (LIS).

</DOC>
<DOC>
<DOCNO> 121306 </DOCNO>
Synchrotron Model for the Infrared, Optical and X-Ray Emission of the


  We develop a model for the infrared, optical and soft X-ray emission of the
Crab pulsar in terms of anisotropic synchrotron emission by relativistic
particles in an outer gap scenario with a single energy distribution. It is
shown that such a distribution is naturally produced in an efficient pair
cascade and that the energy of the primary particles are limited by synchrotron
radiation. It is further shown that this synchrotron model is able to reproduce
the spectral shape between the infrared and soft X-rays and also the
corresponding luminosities. In particular, the long standing problem of the
rapid spectral decline towards infrared frequencies is understandable as
emission at very small pitch angles from low energy particles. Finally, we show
that the scaling of our synchrotron model explains the observed correlation
between the X-ray luminosity and the spin-down luminosity of the neutron star.

</DOC>
<DOC>
<DOCNO> 85396 </DOCNO>
Constraints on Area Variables in Regge Calculus


  We describe a general method of obtaining the constraints between area
variables in one approach to area Regge calculus, and illustrate it with a
simple example. The simplicial complex is the simplest tessellation of the
4-sphere. The number of independent constraints on the variations of the
triangle areas is shown to equal the difference between the numbers of
triangles and edges, and a general method of choosing independent constraints
is described. The constraints chosen by using our method are shown to imply the
Regge equations of motion in our example.

</DOC>
<DOC>
<DOCNO> 70012 </DOCNO>
Kaon Condensation in High Density Quark Matter


  We point out that the problem of kaon condensation in dense hadronic matter
can be addressed in perturbative QCD. Indeed, perturbative calculations suggest
that negative kaons are condensed in high density quark matter if the
electroweak interaction is taken into account. This observation sheds new light
on the proposal that the low density hyperon and high density quark phase of
QCD are continuously connected.

</DOC>
<DOC>
<DOCNO> 40667 </DOCNO>
B-\bar{B} Mixing and b Hadron Lifetimes from Lattice QCD


  We discuss neutral B_{s,d} meson mixing and b-hadron lifetimes from the
perspective of recent lattice calculations. In particular, we consider matrix
elements which can be combined with measured \Delta M_{s,d} to constrain
|V_{td}|, the lifetime ratios \tau(\Lambda_b)/\tau(B_d) and \tau(B^-)/\tau(B_d)
and the lifetime difference, \Delta\Gamma_s/\Gamma_s, in the neutral B_s meson
system.

</DOC>
<DOC>
<DOCNO> 9668 </DOCNO>
Effective Field Theory for Dilute Fermi Systems


  The virtues of an effective field theory (EFT) approach to many-body problems
are illustrated by deriving the expansion for the energy of an homogeneous,
interacting Fermi gas at low density and zero temperature. A renormalization
scheme based on dimensional regularization with minimal subtraction leads to a
more transparent power-counting procedure and diagrammatic expansion than
conventional many-body approaches. Coefficients of terms in the expansion with
logarithms of the Fermi momentum are determined by the renormalization
properties of the EFT that describes few-body scattering. Lessons for an EFT
treatment of nuclear matter are discussed.

</DOC>
<DOC>
<DOCNO> 122114 </DOCNO>
Structure and Mass Distribution of the Milky Way Bulge and Disk


  This article summarizes the structural parameters of the Galactic bulge and
disk, and discusses the interpretation of the bulge microlensing observations
and the determination of the Milky Way's luminous mass from the terminal
velocity curve and the Oort limit. The bulge is a rotating bar with corotation
radius around 4 kpc. The NIR disk has a short scale-length. The measured
surface density of the local disk is in good agreement with the prediction of a
maximum NIR disk model for the Milky Way. The preliminary new value for the
microlensing optical depth of clump giant sources is within $1.7\sigma$ of the
prediction by the maximum NIR disk model, while the optical depth for all
sources is still significantly higher. These results imply that cold dark
matter cannot dominate inside the solar radius.

</DOC>
<DOC>
<DOCNO> 116465 </DOCNO>
Gravitational potential energy of simple bodies: the method of negative


  The method of negative density is presented which allows to obtain the
analytical solutions for potential energy of new kinds of homogeneous and
ihhomogeneous self-gravitating bodies. The homogeneous bispherical
concavo-convex lens is considered in particular.

</DOC>
<DOC>
<DOCNO> 121414 </DOCNO>
The Galaxy Environment of Quasars in the z~1.3 Clowes-Campusano Large


  We report significant associated clustering in the field of a z=1.226 quasar
from the Clowes-Campusano LQG in the form of both a factor ~11 overdensity of
I-K>3.75 galaxies and red sequences of 15-18 galaxies at I-K~4.3, V-K~6.9
indicative of a population of massive ellipticals at the quasar redshift. The
quasar is located between two groups of these galaxies, with further clustering
extending over 2-3 Mpc. A band of V-I<1 galaxies bisects the two groups of red
sequence galaxies, and we suggest that the merging of these two groups has
triggered both this band of star-formation and the quasar.

</DOC>
<DOC>
<DOCNO> 102773 </DOCNO>
Invitation to higher local fields, Part I, section 8: Explicit formulas


  This is a review of the vast area of explicit formulas for the (wild) Hilbert
symbol (not only in the one-dimensional case but in the higher dimensional case
as well). An extensive bilbiography is included.

</DOC>
<DOC>
<DOCNO> 174594 </DOCNO>
Observation of $\rho / \omega$ Meson Modification in Nuclear Matter


  We have measured invariant mass spectra of electron-positron pairs in the
target rapidity region of 12GeV p+A reactions. We have observed a significant
difference in the mass spectra below the $\omega$ meson between p+C and p+Cu
interactions. The difference is interpreted as a signature of the $\rho/\omega$
modification at normal nuclear-matter density.

</DOC>
<DOC>
<DOCNO> 102368 </DOCNO>
A Laguerre Polynomial Orthogonality and the Hydrogen Atom


  The radial part of the wave function of an electron in a Coulomb potential is
the product of a Laguerre polynomial and an exponential with the variable
scaled by a factor depending on the degree. This note presents an elementary
proof of the orthogonality of wave functions with differing energy levels. It
is also shown that this is the only other natural orthogonality for Laguerre
polynomials. By expanding in terms of the usual Laguerre polynomial basis an
analogous strange orthogonality is obtained for Meixner polynomials.

</DOC>
<DOC>
<DOCNO> 70782 </DOCNO>
Horizontal $U(1)_H$ symmetry: a non-anomalous model


  Spontaneously broken Abelian gauge symmetries can explain the fermion mass
hierarchies of the minimal supersymmetric standard model. In most cases it is
assumed that the $U(1)_H$ symmetry is anomalous. However, non-anomalous models
are also viable and yield an interesting phenomenology. Cancellation of the
gauge anomalies implies the following results: unification of leptons and
down-type quarks Yukawa couplings is allowed at most for two generations. The
$\mu$ term is necessarily somewhat below the supersymmetry breaking scale. The
superpotential has accidental $B$ and $L$ symmetries, and R-parity is
automatically conserved in the supersymmetric limit. Anomaly canncellation also
implies that the determinant of the quark mass matrix must vanish, wich is
possible only if $m_{up}=0$. This solves the strong CP problem and provides an
unambiguous low energy test of the model.

</DOC>
<DOC>
<DOCNO> 72094 </DOCNO>
The quest for the Cabibbo Kobayashi Maskawa Matrix


  A piece of the Standard Model presently undergoing intense experimental
scrutiny is the Cabibbo Kobayashi Maskawa matrix. Several different
measurements are planned to enrich the spectrum of experimental constraints and
thus provide one of the most stringent tests of Standard Model validity. The
success of this program is closely related to theoretical progress in
evaluating QCD matrix elements in a non-perturbative regime, as we need to
extract fundamental quark properties from observations on decays involving
hadrons. This interplay between experimental and theoretical progress will be
illustrated in the context of the present knowledge of the magnitudes of the
quark mixing parameters $| V_{cb}| $ and $| V_{ub}|$.

</DOC>
<DOC>
<DOCNO> 150343 </DOCNO>
Holography, Singularities on Orbifolds and 4D N=2 SQCD


  Type II string theory compactified on a Calabi-Yau manifold, with a
singularity modeled by a hypersurface in an orbifold, is considered. In the
limit of vanishing string coupling, one expects a non gravitational theory
concentrated at the singularity. It is proposed that this theory is
holographicly dual to a family of ``non-critical'' superstring vacua,
generalizing a previous proposal for hypersurfaces in flat space. It is argued
that a class of such singularities is relevant for the study of non-trivial IR
fixed points that appear in the moduli space of four-dimensional N=2 SQCD:
SU(N_c) gauge theory with matter in the fundamental representation. This
includes the origin in the moduli space of the SU(N_c) gauge theory with
N_f=2N_c fundamentals. The 4D IR fixed points are studied using the
anti-holographic description and the results agree with information available
from gauge theory.

</DOC>
<DOC>
<DOCNO> 120739 </DOCNO>
The local space density of Sb-Sdm galaxies as function of their


  We investigate the dependence of the local space density of spiral galaxies
on luminosity, scalesize and surface brightness. We derive bivariate space
density distributions in these quantities from a sample of about 1000 Sb-Sdm
spiral galaxies, corrected for selection effects in luminosity and surface
brightness. The structural parameters of the galaxies were corrected for
internal extinction using a description depending on galaxy surface brightness.
We find that the bivariate space density distribution of spiral galaxies in the
(luminosity, scalesize)-plane is well described by a Schechter luminosity
function in the luminosity dimension and a log-normal scale size distribution
at a given luminosity. This parameterization of the scalesize distribution was
motivated by a simple model for the formation of disks within dark matter
halos, with halos acquiring their angular momenta through tidal torques from
neighboring objects, and the disk specific angular momentum being proportional
to that of the parent halo. However, the fractional width of the scalesize
distribution at a given luminosity is narrower than what one would expect from
using the distribution of angular momenta of halos measured in N-body
simulations. We present several possible explanations for the narrowness of the
observed distribution. Using our bivariate distribution, we find that
determinations of the local luminosity function of spiral galaxies should not
be strongly affected by the bias against low surface brightness galaxies, even
when the galaxies are selected from photographic plates. This may not be true
for studies at high redshift, where (1+z)^4 surface brightness dimming can
cause a significant selection bias against lower surface brightness galaxies.

</DOC>
<DOC>
<DOCNO> 71132 </DOCNO>
Polarized and Unpolarized Structures of the Virtual Photon


  We discuss the structure functions and the parton distributions in the
virtual photon target, both polarized and unpolarized, beyond the leading order
in QCD. We study the factorization-scheme dependence of the parton
distributions.

</DOC>
<DOC>
<DOCNO> 151656 </DOCNO>
Supersymmetric Yang-Mills Theory in Eleven Dimensions


  We present a Lorentz invariant lagrangian formulation for a supersymmetric
Yang-Mills vector multiplet in eleven dimensions (11D). The Lorentz symmetry is
broken at the field equation level, and therefore the breaking is spontaneous,
as in other formulations of supersymmetric theories in 12D or higher
dimensions. We introduce a space-like unit vector formed by the gradient of a
scalar field, avoiding the problem of Lorentz non-invariance at the lagrangian
level, which is also an analog of non-commutative geometry with constant field
strengths breaking Lorentz covariance. The constancy of the space-like unit
vector field is implied by the field equation of a multiplier field. The field
equations for the physical fields are formally the same as those of 10D
supersymmetric Yang-Mills multiplet, but now with some constraints on these
fields for supersymmetric consistency. This formulation also utilizes the
multiplier fields accompanied by the bilinear forms of constraints, such that
these multiplier fields will not interfere with the physical field equations.
Based on this component result, we also present a $\k$-symmetric supermembrane
action with the supersymmetric Yang-Mills backgrounds.

</DOC>
<DOC>
<DOCNO> 83269 </DOCNO>
UNIX Resource Managers: Capacity Planning and Resource Issues


  The latest implementations of commercial UNIX to offer mainframe style
capacity management on enterprise servers include: AIX Workload Manager (WLM),
HP-UX Process Resource Manager (PRM), Solaris Resource Manager (SRM), as well
as SGI and Compaq. The ability to manage server capacity is achieved by making
significant modifications to the standard UNIX operating system so that
processes are inherently tied to specific users. Those users, in turn, are
granted only a certain fraction of system resources. Resource usage is
monitored and compared with each users grant to ensure that the assigned
entitlement constraints are met. In this paper, we begin by clearing up some of
the confusion that has surrounded the motivation and the terminology behind the
new technology. The common theme across each of the commercial implementations
is the introduction of the fair-share scheduler. After reviewing some potential
performance pitfalls, we present capacity planning guidelines for migrating to
automated UNIX resource management.

</DOC>
<DOC>
<DOCNO> 102858 </DOCNO>
Stable maps and Quot schemes


  In this paper we study the relationship between two different
compactifications of the space of vector bundle quotients of an arbitrary
vector bundle on a curve. One is Grothendieck's Quot scheme, while the other is
a moduli space of stable maps to the relative Grassmannian.
  We establish an essentially optimal upper bound on the dimension of the two
compactifications. Based on that, we prove that for an arbitrary vector bundle,
the Quot schemes of quotients of large degree are irreducible and generically
smooth. We precisely describe all the vector bundles for which the same thing
holds in the case of the moduli spaces of stable maps. We show that there are
in general no natural morphisms between the two compactifications. Finally, as
an application, we obtain new cases of a conjecture on effective base point
freeness for pluritheta linear series on moduli spaces of vector bundles.

</DOC>
<DOC>
<DOCNO> 120191 </DOCNO>
Quasistellar Objects: Intervening Absorption Lines


  We briefly review, at a level appropriate for graduate students and
non-specialists, the field of quasar absorption lines (QALs). Emphasis is on
the intervening absorbers. We present the anatomy of a quasar spectrum due to
various classes of intervening absorption systems, and a brief historical
review of each absorber class (Lyman-alpha forest and Lyman limit systems, and
metal-line and damped Lyman-alpha absorbers). We also provide several heuristic
examples on how the physical properties of both the intergalactic medium and
the gaseous environments associated with earlier epoch galaxies can be inferred
from QALs. The evolution of these environments from z=4 are discussed.

</DOC>
<DOC>
<DOCNO> 70685 </DOCNO>
Predictions for the Decays of Radially-Excited Baryons


  We consider decays of the lowest-lying radially excited baryons. Assuming a
single-quark decay approximation, and negligible configuration mixing, we make
model-independent predictions for the partial decay widths to final states with
a single meson. Masses of unobserved states are predicted using an old mass
formula rederived using large-$N_c$ QCD. The momentum dependence of the
one-body decay amplitude is determined phenomenologically by fitting to
observed decays. Comparison of these predictions to experiment may shed light
on whether the Roper resonance can be interpreted as a three-quark state.

</DOC>
<DOC>
<DOCNO> 122911 </DOCNO>
The BMW (Brera-Multiscale-Wavelet) Catalogue of Serendipitous X-ray


  In collaboration with the Observatories of Palermo and Rome and the SAX-SDC
we are constructing a multi-site interactive archive system featuring specific
analysis tools. In this context we developed a detection algorithm based on the
Wavelet Transform (WT) and performed a systematic analysis of all ROSAT-HRI
public data (~3100 observations +1000 to come). The WT is specifically suitable
to detect and characterize extended sources while properly detecting point
sources in very crowded fields. Moreover, the good angular resolution of HRI
images allows the source extension and position to be accurately determined.
This effort has produced the BMW (Brera Multiscale Wavelet) catalogue, with
more than 19,000 sources detected at the 4.2 sigma level. For each source
detection we have information on the X-ray flux and extension, allowing for
instance to select complete samples of extended X-ray sources such as candidate
clusters of galaxies or SNR's. Here we present an overview of first results
from several undergoing projects which make use of the BMW catalogue.

</DOC>
<DOC>
<DOCNO> 70476 </DOCNO>
Discovery of a new particle named a coretron and a non-baryionic dark


  %auto-ignore This paper has been withdrawn by the author(s) since somebody do
not agree with my idea.

</DOC>
<DOC>
<DOCNO> 178812 </DOCNO>
Critical Phenomena in Finite Systems


  We discuss the dynamics of finite systems within molecular dynamics models.
Signatures of a critical behavior are analyzed and compared to experimental
data both in nucleus-nucleus and metallic cluster collisions. We suggest the
possibility to explore the instability region via tunneling. In this way we can
obtain fragments at very low temperatures and densities. We call these
fragments quantum drops.

</DOC>
<DOC>
<DOCNO> 13005 </DOCNO>
Critical Behavior of a Chiral Condensate with a Meron Cluster Algorithm


  A new meron cluster algorithm is constructed to study the finite temperature
critical behavior of the chiral condensate in a $(3+1)$ dimensional model of
interacting staggered fermions. Using finite size scaling analysis the infinite
volume condensate is shown to be consistent with the behavior of the form
$(T_c-T)^{0.314(7)}$ for temperatures less than the critical temperature and
$m^{1/4.87(10)}$ at the critical temperature confirming that the critical
behavior belongs to the 3-d Ising universality class within one to two sigma
deviation. The new method, along with improvements in the implementation of the
algorithm, allows the determination of the critical temperature $T_c$ more
accurately than was possible in a previous study.

</DOC>
<DOC>
<DOCNO> 13662 </DOCNO>
Cooper Instability of Composite Fermions


  When confined to two dimensions and exposed to a strong magnetic field,
electrons screen the Coulomb interaction in a topological fashion; they capture
and even number of quantum vortices and transform into particl es called
`composite fermions'. The fractional quantum Hall effect occurs in such a
system when the ratio (or `filling factor', $\nu$) of the number of electrons
and the degeneracy of their spin-split energy states (the Landau levels) takes
on particular values. The Landau level filling $\nu=1/2$ corresponds to a
metallic state in which the composite fermions form a gapless Fermi sea. But
for $\nu=5/2$, a fractional quantum Hall effect is observed instead; this
unexpected result is the subject of considerable debate and controversy. Here
we investigate the difference between these states by considering the
theoretical problem of two composite fermions on top of a fully polarized Fermi
sea of composite fermions. We find that they undergo Cooper pairing to form a
p-wave bound state at $\nu=5/2$, but not at $\nu=1/2$. In effect, the repulsive
Coulomb interaction between electrons is overscr eened in the $\nu=5/2$ state
by the formation of composite fermions, resulting in a weak, attractive
interaction.

</DOC>
<DOC>
<DOCNO> 122338 </DOCNO>
Radio-quiet quasar environments at 0.5 < z < 0.8


  We have quantified the galaxy environments around a sample of 0.5 < z < 0.8
radio-quiet quasars using the amplitude of the spatial galaxy--quasar
correlation function, B_gq. The quasars exist in a wide variety of
environments, some sources are located in clusters as rich as Abell class 1--2
clusters, whereas others exist in environments comparable to the field. We find
that on average, the quasars prefer poorer clusters of approximately Abell
class 0, which suggests that quasars are biased tracers of mass compared to
galaxies.
  The mean B_gq for the sample is found to be indistinguishable from the mean
amplitude for a sample of radio-loud quasars matched in redshift and optical
luminosity. These observations are consistent with recent studies of the hosts
of radio-quiet quasars at low to intermediate redshifts, and suggest that the
mechanism for the production of powerful radio jets in radio-loud quasars is
controlled by processes deep within the active galactic nucleus itself, and is
unrelated to the nature of the hosts or their environments.

</DOC>
<DOC>
<DOCNO> 116894 </DOCNO>
Test of accelerating structure for VEPP-5 preinjector


  Preinjector VEPP-5 electron linac consists of two linear accelerators on
energy 300 MeV and 510 MeV and includes 14 accelerating structures [1]. First
accelerating structures both linacs have increased average rate of acceleration
25-30 MeV/m, and other regular sections up to 17-20 MeV/m. This paper presents
the results of basic test of 3-meter long accelerating structure. Average rate
of acceleration of an electron beam 35 MeV/m was achieved. The electron beam
energy up to 105 MeV was obtained.

</DOC>
<DOC>
<DOCNO> 121039 </DOCNO>
Evolution of Proto-Neutron stars with kaon condensates


  We present simulations of the evolution of a proto-neutron star in which
kaon-condensed matter might exist, including the effects of finite temperature
and trapped neutrinos. The phase transition from pure nucleonic matter to the
kaon condensate phase is described using Gibbs' rules for phase equilibrium,
which permit the existence of a mixed phase. A general property of neutron
stars containing kaon condensates, as well as other forms of strangeness, is
that the maximum mass for cold, neutrino-free matter can be less than the
maximum mass for matter containing trapped neutrinos or which has a finite
entropy. A proto-neutron star formed with a baryon mass exceeding that of the
maximum mass of cold, neutrino-free matter is therefore metastable, that is, it
will collapse to a black hole at some time during the Kelvin-Helmholtz cooling
stage.
  The effects of kaon condensation on metastable stars are dramatic. In these
cases, the neutrino signal from a hypothetical galactic supernova (distance
$\sim8.5$ kpc) will stop suddenly, generally at a level above the background in
the SuperK and SNO detectors, which have low energy thresholds and backgrounds.
This is in contrast to the case of a stable star, for which the signal
exponentially decays, eventually disappearing into the background. We find the
lifetimes of kaon-condensed metastable stars to be restricted to the range
40--70 s and weakly dependent on the proto-neutron star mass, in sharp contrast
to the significantly larger mass dependence and range (1--100 s) of
hyperon-rich metastable stars.

</DOC>
<DOC>
<DOCNO> 14053 </DOCNO>
Vortex Dynamics and the Problem of the Transverse Force in Clean


  We review the basic ideas and results on the vortex dynamics in clean
superfluid Fermi systems. The forces acting on moving vortices are discussed
including the problem of the transverse force which was a matter of confusion
for quite a time. Finally, we formulate the equations of the vortex dynamics
which include all the forces and the inertial term associated with excitations
bound to the moving vortex.

</DOC>
<DOC>
<DOCNO> 8862 </DOCNO>
Bond and charge density waves in the isotropic interacting


  We report two surprising results regarding the nature of the spatial broken
symmetries in the two-dimensional (2D), quarter-filled band with strong
electron-electron interactions. First, in direct contradiction to the
predictions of one-electron theory, we find a coexisting ``bond-order and
charge density wave'' (BCDW) insulating ground state in the 2D rectangular
lattice for all anisotropies, including the isotropic limit. Second, we find
that the BCDW further coexists with a spin-density wave (SDW) in the range of
large anisotropy. Further, in contrast to the interacting half-filled band, in
the interacting quarter-filled band there are two transitions: first, a similar
singlet-to-AFM/SDW transition for large anisotropy and second, an
AFM/SDW-to-singlet transition at smaller anisotropy. We discuss how these
theoretical results apply to the insulating states that are proximate to the
superconducting states of 2:1 cationic charge-transfer solids (CTS).
 An important consequence of this work is the suggestion that organic
superconductivity is related to the proximate Coulomb-induced BCDW, with the
SDW that coexists for large anisotropies being also a consequence of the BCDW,
rather than the driver of superconductivity.

</DOC>
<DOC>
<DOCNO> 40484 </DOCNO>
A study of B0-anti-B0 oscillations with full reconstructed B mesons with


  Time-dependent B0-anti-B0 flavor oscillations are studied in e+e-
annihilation data collected with the BABAR detector at center-of-mass energies
near the Upsilon(4S) resonance. We report a preliminary result for the
time-dependent B0-anti-B0 oscillation frequency, Delta_md = 0.512 +/- 0.017 +/-
0.022 hbar ps^{-1}.

</DOC>
<DOC>
<DOCNO> 119901 </DOCNO>
Observations of Seyferts by OSSE and parameters of their X-ray/gamma-ray


  We present a summary of spectra of Seyfert galaxies observed by the OSSE
detector aboard Compton Gamma Ray Observatory. We obtain average spectra of
Seyferts of type 1 and 2, and find they are well fitted by thermal
Comptonization. We present detailed parameter ranges for the plasma temperature
and the Compton parameter in the case of spherical and slab geometries. We find
both the average and individual OSSE spectra of Seyfert 2s are significantly
harder than those of Seyfert 1s, which difference can be due to anisotropy of
Compton reflection and/or Thomson-thick absorption.

</DOC>
<DOC>
<DOCNO> 117340 </DOCNO>
Changing Mass Corrects Newtonian Gravity


  Newton's inverse-square law of universal gravitation assumes constant mass.
But mass increases with speed and perhaps with gravity. By SR, mass is
increased over the rest mass by gamma. Rest mass is here postulated to increase
under gravity, by 1/alpha =1+GM/rc^2. We examine the consequences of
introducing this changing mass into Newton's law in flat spacetime. This
variable mass affects the metric, relative to an observer away from the
influence of gravity, contracting both lengths and times (as measured) by
alpha/gamma. The gravitational force, as in orbital calculations, differs from
Newton's law by the factor (gamma/alpha)^3, and is not quite inverse square.
Without adjustable parameters, this accounts fully for the classical tests of
GR. The postulated "fifth force" appears at the 10^-9 g level.
Gravitationally-influenced space remains Euclidean, but the mass-metric changes
make it seem curved when measured.

</DOC>
<DOC>
<DOCNO> 84647 </DOCNO>
Light propagation in non linear electrodynamics


  Working on the approximation of low frequency, we present the light cone
conditions for a class of theories constructed with the two gauge invariants of
the Maxwell field without making use of average over polarization states.
Different polarization states are thus identified describing birefringence
phenomena. We make an application of the formalism to the case of
Euler-Heisenberg effective Lagrangian and well know results are obtained.

</DOC>
<DOC>
<DOCNO> 101436 </DOCNO>
Constructing special Lagrangian m-folds in C^m by evolving quadrics


  This is the second in a series of papers constructing explicit examples of
special Lagrangian submanifolds in C^m. The first paper was math.DG/0008021,
which studied special Lagrangian m-folds with large symmetry groups. The third
is math.DG/0010036, which uses ideas from this paper to construct families of
special Lagrangian 3-folds in C^3.
  This paper describes a construction of special Lagrangian m-folds in C^m
which are fibred by (m-1)-submanifolds which are quadrics in Lagrangian planes
R^m in C^m. Generically they have only discrete symmetry groups. Some of our
examples have been previously constructed by Lawlor and Harvey, using different
methods.
  The principal motivation for these papers is to lay the foundations for the
study of singularities of compact special Lagrangian m-folds in Calabi-Yau
m-folds. Understanding such singularities will be important in resolving the
SYZ conjecture on Mirror Symmetry of Calabi-Yau 3-folds. The special Lagrangian
m-folds in C^m we construct here include many cones on S^a x S^b x S^1 for
a+b=m-2, which are local models for singularities of special Lagrangian m-folds
in Calabi-Yau m-folds.

</DOC>
<DOC>
<DOCNO> 170227 </DOCNO>
Experimental Demonstration of Optimal Unambiguous State Discrimination


  We present the first full demonstration of unambiguous state discrimination
between non-orthogonal quantum states. Using a novel free space interferometer
we have realised the optimum quantum measurement scheme for two non-orthogonal
states of light, known as the Ivanovic-Dieks-Peres (IDP) measurement. We have
for the first time gained access to all three possible outcomes of this
measurement. All aspects of this generalised measurement scheme, including its
superiority over a standard von Neumann measurement, have been demonstrated
within 1.5% of the IDP predictions.

</DOC>
<DOC>
<DOCNO> 152103 </DOCNO>
Ordinary Differential Equations and Integrable Models


  We review a recently-discovered link between the functional relations
approach to integrable quantum field theories and the properties of certain
ordinary differential equations in the complex domain.

</DOC>
<DOC>
<DOCNO> 121572 </DOCNO>
Accretion Disk Instabilities, CDM models and their role in Quasar


  We have developed a consistent analytical model to describe the observed
evolution of the quasar luminosity function. Our model combines black hole mass
distributions based on the Press - Schechter theory of the structure formation
in the Universe with quasar luminosity functions resulting from a physics-based
emission model that takes into account the time-dependent phenomena occurring
in the accretion disks. Quasar evolution and CDM models are mutually
constraining, therefore our model gives an estimation of the exponent, n, of
the power spectrum, P(k), which is found to be -1.8 < n < -1.6. We were able to
reject a generally assumed hypothesis of a constant ratio between Dark Matter
Halo and the Black Hole mass, since the observed data could not be fitted under
this assumption. We found that the relation between the Dark Matter Halos and
Black Hole masses is better described by M_{BH}=M_{DMH}^{0.668}. This model
provides a reasonable fit to the observed quasar luminosity function at
redshifts higher than ~2.0. We suggest that the disagreement at lower redshift
is due to mergers. Based on the agreement at high redshift, we estimated the
merger rate at lower redshift, and argue that this rate should depend on the
redshift, like (1+z)^3.

</DOC>
<DOC>
<DOCNO> 72261 </DOCNO>
Probing the power spectrum bend with recent CMB data


  We constrain the primordial fluctuation spectrum P(k) by using the new data
on the Cosmic Microwave Background (CMB) from the Boomerang and MAXIMA
experiments. Our study is based on slow-roll inflationary models, and we
consider the possibility of a running spectral index. Specifically, we expand
the power spectrum P(k) to second order in ln(k), thus allowing the power
spectrum to ``bend'' in k-space. We show that allowing the power spectrum to
bend erases the ability of the present data to measure the tensor to scalar
perturbation ratio. Moreover, if the primordial baryon density \Omega_b h^2 is
as low as found from Big Bang nucleosynthesis (BBN), the data favor a negative
bending of the power spectrum, corresponding to a bump-like feature in the
power spectrum around a scale of k=0.004 Mpc^-1.

</DOC>
<DOC>
<DOCNO> 80714 </DOCNO>
Gauge Field Theory Coherent States (GCS) : IV. Infinite Tensor Product


  In the canonical approach to Lorentzian Quantum General Relativity in four
spacetime dimensions an important step forward has been made by Ashtekar, Isham
and Lewandowski some eight years ago through the introduction of an appropriate
Hilbert space structure.
  This Hilbert space, together with its generalization due to Baez and Sawin,
is appropriate for semi-classical quantum general relativity if the spacetime
is spatially compact. In the spatially non-compact case, however, an extension
of the Hilbert space is needed in order to approximate metrics that are
macroscopically nowhere degenerate.
  For this purpose, in this paper we apply von Neumann's theory of the Infinite
Tensor Product (ITP) of Hilbert Spaces to Quantum General Relativity. The
cardinality of the number of tensor product factors can take the value of any
possible Cantor aleph as is needed for our problem, where a Hilbert space is
attached to each edge of an arbitrarily complicated, generally infinite graph.
  The new framework opens a pandora's box full of techniques, appropriate to
pose fascinating physical questions such as quantum topology change,
semi-classical quantum gravity, effective low energy physics etc. from the
universal point of view of the ITP. In particular, the study of photons and
gravitons propagating on fluctuating quantum spacetimes is now in reach, the
topic of the next paper in this series.

</DOC>
<DOC>
<DOCNO> 99748 </DOCNO>
Geometrically Graded h-p Quadrature Applied to the Complex Boundary


  Boundary integral methods for the solution of boundary value PDEs are an
alternative to `interior' methods, such as finite difference and finite element
methods. They are attractive on domains with corners, particularly when the
solution has singularities at these corners. In these cases, interior methods
can become excessively expensive, as they require a finely discretised 2D mesh
in the vicinity of corners, whilst boundary integral methods typically require
a mesh discretised in only one dimension, that of arc length.
  Consider the Dirichlet problem. Traditional boundary integral methods applied
to problems with corner singularities involve a (real) boundary integral
equation with a kernel containing a logarithmic singularity. This is both
tedious to code and computationally inefficient. The CBIEM is different in that
it involves a complex boundary integral equation with a smooth kernel. The
boundary integral equation is approximated using a collocation technique, and
the interior solution is then approximated using a discretisation of Cauchy's
integral formula, combined with singularity subtraction.
  A high order quadrature rule is required for the solution of the integral
equation. Typical corner singularities are of square root type, and a
`geometrically graded h-p' composite quadrature rule is used. This yields
efficient, high order solution of the integral equation, and thence the
Dirichlet problem.
  Implementation and experimental results in \textsc{matlab} code are
presented.

</DOC>
<DOC>
<DOCNO> 101221 </DOCNO>
Every diassociative A-loop is Moufang


  An A-loop is a loop in which every inner mapping is an automorphism. We
settle a problem which had been open since 1956 by showing that every
diassociative A-loop is Moufang.

</DOC>
<DOC>
<DOCNO> 118468 </DOCNO>
The Chandra Iron-L X-Ray Line Spectrum of Capella


  An analysis of the iron L-shell emission in the publicly available spectrum
of the Capella binary system, as obtained by the High Energy Transmission
Grating Spectrometer on board the Chandra X-ray Observatory, is presented. The
atomic-state model, based on the HULLAC code, is shown to be especially
adequate for analyzing high-resolution x-ray spectra of this sort. Almost all
of the spectral lines in the 10 - 18 Angstrom wavelength range are identified.
It is shown that, for the most part, these lines can be attributed to emission
from L-shell iron ions in the Capella coronae. Possibilities for electron
temperature diagnostics using line ratios of Fe16+ are demonstrated. It is
shown that the observed iron-L spectrum can be reproduced almost entirely by
assuming a single electron temperature of kTe= 600 eV. This temperature is
consistent with both the measured fractional ion abundances of iron and with
the temperature derived from ratios of Fe16+ lines. A volume emission measure
of 1053 cm-3 is calculated for the iron L-shell emitting regions of the Capella
coronae indicating a rather small volume of 1029 cm3 for the emitting plasma if
an electron density of 1012 cm-3 is assumed.

</DOC>
<DOC>
<DOCNO> 150350 </DOCNO>
Modular invariance of string theory on AdS_3


  We discuss the modular invariance of the SL(2,R) WZW model. In particular, we
discuss in detail the modular invariants using the \hat{sl}(2,R) characters
based on the discrete unitary series of the SL(2,R) representations. The
explicit forms of the corresponding characters are known when no singular
vectors appear. We show, for example, that from such characters modular
invariants can be obtained only when the level k < 2 and infinitely large spins
are included. In fact, we give a modular invariant with three variables
Z(z,\tau, u) in this case. We also argue that the discrete series characters
are not sufficient to construct a modular invariant compatible with the
unitarity bound, which was proposed to resolve the ghost problem of the SL(2,R)
strings.

</DOC>
<DOC>
<DOCNO> 7630 </DOCNO>
Determining the Wiedemann-Franz ratio from the thermal Hall


  The Wiedemann-Franz (WF) ratio compares the thermal and electrical
conductivities in a metal. We describe a new way to determine its value, based
on the thermal Hall conductivity. The technique is applied to copper and to
untwinned YBaCuO. In the latter, we uncover a T-linear dependence and
suppression of the Hall-channel WF ratio. We discuss the implications of this
suppressions. The general suppression of the WF ratio in systems with
predominant electron-electron scattering is discussed.

</DOC>
<DOC>
<DOCNO> 8488 </DOCNO>
Microcanonical Foundation for Systems with Power-Law Distributions


  Starting from microcanonical basis with the principle of equal a priori
probability, it is found that, besides ordinary Boltzmann-Gibbs theory with the
exponential distribution, a theory describing systems with power-law
distributions can also be derived.

</DOC>
<DOC>
<DOCNO> 152421 </DOCNO>
Seiberg-Witten Toda Chains and N=1 SQCD


  We consider the Seiberg-Witten Toda chains arising in the context of exact
solutions to N=2 SUSY Yang-Mills and their relation to the properties of N=1
SUSY gauge theories. In particular, we discuss their "perturbative" and
"solitonic" degenerations and demonstrate some relations of the latter ones to
the confining properties of N=1 vacua.

</DOC>
<DOC>
<DOCNO> 84248 </DOCNO>
Matters of Gravity, the newsletter of the APS Topical Group on


  News:
  TGG session in the April meeting, by Cliff Will NRC report, by Beverly Berger
MG9 Travel Grant for US researchers, by Jim Isenberg Research Briefs:
  How many coalescing binaries are there?, by Vicky Kalogera Recent
developments in black critical phenomena, by Pat Brady Optical black holes?, by
Matt Visser ``Branification:'' an alternative to compactification, by Steve
Giddings Searches for non-Newtonian Gravity at Sub-mm Distances, by Riley
Newman Quiescent cosmological singularities by Bernd Schmidt The debut of LIGO
II, by David Shoemaker Is the universe still accelerating?, by Sean Carroll
Conference reports:
  Journ\' ees Relativistes Weimar 1999, by Volker Perlick The 9th Midwest
Relativity Meeting, by Thomas Baumgarte

</DOC>
<DOC>
<DOCNO> 122994 </DOCNO>
Surveys and the Blazar Parameter Space


  The rareness of blazars, combined with the previous history of relatively
shallow, single-band surveys, has dramatically colored our perception of these
objects. Despite a quarter-century of research, it is not at all clear whether
current samples can be combined to give us a relatively unbiased view of blazar
properties, or whether they present a view so heavily affected by biases
inherent in single-band surveys that a synthesis is impossible. We will use the
coverage of X-ray/radio flux space for existing surveys to assess their biases.
Only new, deeper blazar surveys approach the level needed in depth and coverage
of parameter space to give us a less biased view of blazars. These surveys have
drastically increased our knowledge of blazars' properties. We will
specifically review the discovery of ``blue'' blazars, objects with broad
emission lines but broadband spectral characteristics similar to HBL BL Lac
objects.

</DOC>
<DOC>
<DOCNO> 102450 </DOCNO>
Geometry and Moduli Space of Certain Rank-4 Vector Bundles on ${\mathbb


  Mathematical instanton bundles of rank 4 and $c_2=2$ on ${\mathbb P}^4$ have
a smoothquasiprojective moduli space, which is shown via a direct GIT
construction. A complete classification of jumping lines of these vector
bundles is obtained. The duals of these bundles are described. Dimension
computations and irreducibility proofs for some "interesting" subsets of the
moduli space are presented. Restrictions of vector bundles from ${\mathbb P}^4$
to ${\mathbb P}^3$ are shown to produce mathematical instanton bundles on
${\mathbb P}^3$.

</DOC>
<DOC>
<DOCNO> 121254 </DOCNO>
Reconnection in a striped pulsar wind


  It is generally thought that most of the spin-down power of a pulsar is
carried away in an MHD wind dominated by Poynting flux. In the case of an
oblique rotator, a significant part of this energy can be considered to be in a
low-frequency wave, consisting of stripes of toroidal magnetic field of
alternating polarity, propagating in a region around the equatorial plane.
Magnetic reconnection in such a structure has been proposed as a mechanism for
transforming the Poynting flux into particle energy in the pulsar wind. We have
re-examined this process and conclude that the wind accelerates significantly
in the course of reconnection. This dilates the timescale over which the
reconnection process operates, so that the wind requires a much larger distance
than was previously thought in order to convert the Poynting flux to particle
flux. In the case of the Crab, the wind is still Poynting-dominated at the
radius at which a standing shock is inferred from observation. An estimate of
the radius of the termination shock for other pulsars implies that all except
the milli-second pulsars have Poynting-flux dominated winds all the way out to
the shock front.

</DOC>
<DOC>
<DOCNO> 122116 </DOCNO>
The effect of violent star formation on the state of the molecular gas


  We present the results of a high angular resolution, multi-transition
analysis of the molecular gas in M82. The analysis is based on the two lowest
transitions of 12CO and the ground transition of the rare isotopes 13CO and
C18O measured with the PdBI, the BIMA array and the IRAM 30m telescope. In
order to address the question of how the intrinsic molecular cloud properties
are influenced by massive star formation we have carried out radiative transfer
calculations based on the observed CO line ratios. The calculations suggest
that the kinetic temperature of the molecular gas is high in regions with
strong star formation and drops towards the outer molecular lobes with less
ongoing star formation. The location of the highest kinetic temperature is
coincident with that of the mid infrared peaks which trace emission from hot
dust. The hot gas is associated with low H2 densities while the cold gas in the
outer molecular lobes has high H2 densities. We find that CO intensities do not
trace H2 column densities well. Most of the molecular gas is distributed in a
double-lobed distribution which surrounds the starburst. A detailed analysis of
the conversion factor from CO intensity to H2 column density shows that X_CO
depends on the excitation conditions. We find X_CO ~ Sqrt(n_H2)/T_kin, as
expected for virialized clouds.

</DOC>
<DOC>
<DOCNO> 70689 </DOCNO>
Experimental Puzzles in Heavy Flavor Decays - Anomalously high $\eta'$


  Simple experimental tests are proposed which can clarify the origin for the
anomalously high $\eta'$ appearance in charmless strange final states in $B$
decays and can investigate the the nature of SU(3) symmetry-breaking in weak
heavy flavor decays.

</DOC>
<DOC>
<DOCNO> 13118 </DOCNO>
Isotope effects in underdoped cuprate superconductors: a quantum


  We show that the unusual doping dependence of the isotope effects on
transition temperature and zero temperature in - plane penetration depth
naturally follows from the doping driven 3D-2D crossover, the 2D quantum
superconductor to insulator transition (QSI) in the underdoped limit and the
change of the relative doping concentration upon isotope substitution. Close to
the QSI transition both, the isotope coefficient of transition temperature and
penetration depth approach the coefficient of the relative dopant
concentration, and its divergence sets the scale. These predictions are fully
consistent with the experimental data and imply that close to the underdoped
limit the unusual isotope effect on transition temperature and penetration
depth uncovers critical phenomena associated with the quantum superconductor to
insulator transition in two dimensions.

</DOC>
<DOC>
<DOCNO> 7747 </DOCNO>
Magnetic Susceptibilities of Spin-1/2 Antiferromagnetic Heisenberg


  A comprehensive theoretical and experimental study is presented of the
magnetic susceptibility versus temperature \chi(T) of spin S = 1/2 two- and
three-leg Heisenberg ladders and ladder oxide compounds. Extensive quantum
Monte Carlo simulations of \chi(T) were carried out for both isolated and
coupled two-leg ladders with spatially anisotropic intraladder exchange.
Accurate fits to these and related literature QMC data were obtained. We have
also calculated the one- and two-magnon dispersion relations and the dynamical
spin structure factor for anisotropic isolated 2 x 12 ladders. The exchange
constants in the two-leg ladder compound SrCu2O3 are estimated from LDA+U
calculations. We report the detailed crystal structure of SrCu2O3 and of the
three-leg ladder compound Sr2Cu3O5. New experimental \chi(T) data are reported
for the two-leg ladder cuprates SrCu2O3 and LaCuO_{2.5}, and for the
(nominally) two-leg ladder vanadates CaV2O5 and MgV2O5. The new and literature
\chi(T) data for these compounds and for Sr2Cu3O5 are modeled using our QMC
\chi(T) simulation fits, and the exchange coupling constants between the
spins-1/2 are thereby estimated for each material. The surpisingly strong
spatial anisotropy of the bilinear intraladder exchange constants in the
cuprate compounds is discussed together with the results of other experiments
sensitive to this anisotropy. Recent theoretical predictions are discussed
including those which indicate that a four-spin cyclic exchange interaction
within a Cu4 plaquette is important to determining the magnetic properties and
which can significantly influence the exchange interactions estimated from
\chi(T) data assuming the presence of only bilinear exchange.

</DOC>
<DOC>
<DOCNO> 152466 </DOCNO>
Annihilation and creation operators in non-Hermitian supersymmetric


  Harmonic oscillators with a centrifugal spike are analysed, via a
non-Hermitian regularization, within a complexified SUSY quantum mechanics. The
formalism enables us to construct the factorized creation and annihilation
operators. We show how the real though, generically, non-equidistant spectrum
complies with the current SUSY-type isospectrality and degeneracy in an unusual
way.

</DOC>
<DOC>
<DOCNO> 40547 </DOCNO>
Exclusive Measurements in B to D^* N Nbar X


  We report the first observation of exclusive decays of the type B to D^* N
Nbar X, where N is a nucleon. Using a sample of 9.7 x 10^6 BBbar pairs
collected with the CLEO detector operating at the Cornell Electron Storage
Ring, we measure the branching fractions B(B^0 to D^*-p pbar pi^+) =
(6.5+1.3-1.2 +-1.0) x 10^-4, and B(B^0 to D^*- p nbar) = (14.5+3.4-3.0 +-2.7) x
10^-4. The charge conjugate process is implied in the reconstruction of B^0 to
D^*- p nbar, only the mode with the antineutron is used in our measurement
because neutrons do not have a distinctive annihilation signature.
  Antineutrons are used for the first time in the exclusive reconstruction of a
B meson. By finding conclusive evidence for the existence of decay modes of the
type B to D N Nbar X, we challenge the assumption that the B to Baryons rate is
dominated by decays to charmed mesons.

</DOC>
<DOC>
<DOCNO> 12928 </DOCNO>
Surfactants in semiconductor heteroepitaxy: Thermodynamics and/or


  The effect of surfactants on the thermodynamics and kinetics of semiconductor
heteroepitaxy is briefly discussed. It is argued that the way the surfactants
suppress the thermodynamic driving force for 3D islanding depends on the
mechanism of exchange of overlayer and surfactant atoms. If the overlayer atoms
occupy bulk-like positions provided by the outgoing surfactant dimers, as is
the case of Ge/Si(001), large atomic displacements are forcibly inhibited, and
the wetting of the overlayer by the substrate becomes nearly complete. This
complete wetting of the overlayer by the substrate means a zero thermodynamic
driving force for 3D islanding. Once the thermodynamics do not require 3D
islanding a change of the growth mode with the temperature should not be
observed. Thus, the temperature change of the growth mode appears as an
indication for the primary role of the kinetics, as in the case of Ge/Si(111).

</DOC>
<DOC>
<DOCNO> 120509 </DOCNO>
Wandering Among Newton Wonders


  In the electromagnetic fields t^2 B = b(r/t), E = r x B/t trajectories of
non-relativistic charged particles conserve (r-vt)^2. The transformation r'=r/t
t'=1/t maps such trajectories into orbits in the constant magnetic field all of
which conserve kinetic energy. The transformation may also be used to transform
any fields obeying Curl E = B/dt, div B = 0 into others and relates the
particle trajectories in them.

</DOC>
<DOC>
<DOCNO> 123007 </DOCNO>
Formation Mechanisms for Spirals in Barred Galaxies


  We consider a scenario of formation of the spiral structure in barred
galaxies. This scenario includes the new non-resonant mechanism of elongation
of spirals, due to the characteristic behaviour of the gravitational potential
beyond the principal spiral arms.

</DOC>
<DOC>
<DOCNO> 152649 </DOCNO>
Correlation functions in the non-commutative Wess-Zumino-Witten model


  We develop a systematic perturbative expansion and compute the one-loop
two-points, three-points and four-points correlation functions in a
non-commutative version of the U(N) Wess-Zumino-Witten model in different
regimes of the $\theta$-parameter showing in the first case a kind of phase
transition around the value $\theta_c = \frac{\sqrt{p^2 + 4 m^2}}{\Lambda^2
p}$, where $\Lambda$ is a ultraviolet cut-off in a Schwinger regularization
scheme. As a by-product we obtain the functions of the renormalization group,
showing they are essentially the same as in the commutative case but applied to
the whole U(N) fields; in particular there exists a critical point where they
are null, in agreement with a recent background field computation of the
beta-function, and the anomalous dimension of the Lie algebra-valued field
operator agrees with the current algebra prediction. The non-renormalization of
the level $k$ is explicitly verified from the four-points correlator, where a
left-right non-invariant counter-term is needed to render finite the theory,
that it is however null on-shell. These results give support to the equivalence
of this model with the commutative one.

</DOC>
<DOC>
<DOCNO> 117678 </DOCNO>
The abundance of high-redshift objects as a probe of non-Gaussian


  The observed abundance of high-redshift galaxies and clusters contains
precious information about the properties of the initial perturbations. We
present a method to compute analytically the number density of objects as a
function of mass and redshift for a range of physically motivated non-Gaussian
models. In these models the non-Gaussianity can be dialed from zero and is
assumed to be small. We compute the probability density function for the
smoothed dark matter density field and we extend the Press and Schechter
approach to mildly non-Gaussian density fields. The abundance of high-redshift
objects can be directly related to the non-Gaussianity parameter and thus to
the physical processes that generated deviations from the Gaussian behaviour.
Even a skewness parameter of order 0.1 implies a dramatic change in the
predicted abundance of $z\gap 1$ objects. Observations from NGST and X-ray
satellites (XMM) can be used to accurately measure the amount of
non-Gaussianity in the primordial density field.

</DOC>
<DOC>
<DOCNO> 101583 </DOCNO>
Topological quantum field theory and hyperk\"ahler geometry


  Rozansky and Witten proposed a 3-dimensional sigma-model whose target space
is a hyperk\"ahler manifold. They conjectured that this theory has an
associated TQFT, with Hilbert spaces given by certain cohomology groups of the
hyperk\"ahler manifold. On the other hand, there is a certain modified TQFT
constructed by Murakami and Ohtsuki using the universal quantum invariant. We
explain how the Rozansky-Witten TQFT can be obtained from the latter by
applying a `hyperk\"ahler weight system'.

</DOC>
<DOC>
<DOCNO> 84796 </DOCNO>
Microscopic Black Hole Pairs in Highly-Excited States


  We consider the quantum mechanics of a system consisting of two identical,
Planck-size Schwarzschild black holes revolving around their common center of
mass. We find that even in a very highly-excited state such a system has very
sharp, discrete energy eigenstates, and the system performs very rapid
transitions from a one stationary state to another. For instance, when the
system is in the 100th excited state, the life times of the energy eigenstates
are of the order of $10^{-30}$ s, and the energies of gravitons released in
transitions between nearby states are of the order of $10^{22}$ eV.

</DOC>
<DOC>
<DOCNO> 68225 </DOCNO>
Central Baryons in Dual Models and the Possibility of a Backward Peak in


  Two distinct interactions of Pomerons should occur in dense multi-string
events. Besides the usual triple Pomeron processes transitions to membraned
cylinders can be expected to contribute in a significant way. They offer an
efficient mechanism for central baryon production and for the long range
transport of initial baryons. The slope of such an exchange should be quite low
as it is related to the Odderon known from the leading logarithmic
approximation. Such a flat trajectory has to be suppressed by small coupling
constants. It is argued that this strong suppression does not appear in
diffractive events. In consequence there should be a tiny observable backward
peak in the initial baryon distribution even in quite massive diffractive
systems.

</DOC>
<DOC>
<DOCNO> 12752 </DOCNO>
Semi-fermionic representation of SU(N) Hamiltonians


  We represent the generators of the SU(N) algebra as bilinear combinations of
Fermi operators with imaginary chemical potential. The distribution function,
consisting of a minimal set of discrete imaginary chemical potentials, is found
for arbitrary N. This representation leads to the conventional temperature
diagram technique with standard Feynman codex, except that the Matsubara
frequencies are determined by neither integer nor half-integer numbers. The
real-time Schwinger-Keldysh formalism is formulated in the framework of complex
distribution functions. We discuss the continuous large N and SU(2) large spin
limits. We illustrate the application of this technique for magnetic and
spin-liquid states of the Heisenberg model.

</DOC>
<DOC>
<DOCNO> 123281 </DOCNO>
Exploration of Large Digital Sky Surveys


  We review some of the scientific opportunities and technical challenges posed
by the exploration of the large digital sky surveys, in the context of a
Virtual Observatory (VO). The VO paradigm will profoundly change the way
observational astronomy is done. Clustering analysis techniques can be used to
discover samples of rare, unusual, or even previously unknown types of
astronomical objects and phenomena. Exploration of the previously poorly probed
portions of the observable parameter space are especially promising. We
illustrate some of the possible types of studies with examples drawn from
DPOSS; much more complex and interesting applications are forthcoming.
Development of the new tools needed for an efficient exploration of these vast
data sets requires a synergy between astronomy and information sciences, with
great potential returns for both fields.

</DOC>
<DOC>
<DOCNO> 102251 </DOCNO>
Symmetry, singularities and integrability in complex dynamics III:


  The different natures of approximate symmetries and their corresponding first
integrals/invariants are delineated in the contexts of both Lie symmetries of
odes and Noether symmetries of the Action Integral. Particular note is taken of
the effect of taking higher orders of the perturbation parameter. Approximate
symmetries of approximate first integrals/invariants and the problems of
calculating them using the Lie method are considered.

</DOC>
<DOC>
<DOCNO> 7787 </DOCNO>
Nonsingular vortices in (s+d)-wave superconductors


  The structure of a single flux line in (s+d)-wave superconductors has been
analyzed within the Ginzburg-Landau (GL) model generalized for two order
parameter components. The fourfold symmetric singular vortex solution is shown
to be unstable in a certain range of the GL parameters with respect to the
mutual shift of s- and d- wave unit vortices. The resulting nonsingular vortex
structure is studied both analytically and numerically.

</DOC>
<DOC>
<DOCNO> 102593 </DOCNO>
Symplectic resolutions: deformations and birational maps


  Unfortunately, some proofs in the first version of this paper were incorrect.
In this revised version, some minor gaps are fixed, one serious mistake found.
The main theorem is now claimed only under a restrictive technical assumption.
This invalidates the application to quotient singularities by the Weyl group of
type $G_2$. Everything else still stands (in particular, the claim that every
symplectic resolution is semismall).

</DOC>
<DOC>
<DOCNO> 84732 </DOCNO>
Ghost Equations and Diffeomorphism Invariant Theories


  Four-dimensional Einstein gravity in the Palatini first order formalism is
shown to possess a vector supersymmetry of the same type as found in the
topological theories for Yang-Mills fields. A peculiar feature of the
gravitational theory, characterized by diffeomorphism invariance, is a direct
link of vector supersymmetry with the field equation of motion for the
Faddeev-Popov ghost of diffeomorphisms.

</DOC>
<DOC>
<DOCNO> 119715 </DOCNO>
The 12C/13C-ratio in cool carbon stars


  We present observations of circumstellar millimetre-wave 13CO line emission
towards a sample of 20 cool carbon stars. Using a detailed radiative transfer
model we estimate the circumstellar 12CO/13CO-ratios, which we believe
accurately measure the important stellar 12C/13C-ratios. For those optically
bright carbon stars where it is possible, our derived 12C/13C-ratios are
compared with the photospheric results, obtained with different methods. Our
estimates agree well with those of Lambert et al. (1986).
  It is shown that a straightforward determination of the 12CO/13CO-ratio from
observed line intensity ratios is often hampered by optical depth effects, and
that a detailed radiative transfer analysis is needed in order to determine
reliable isotope ratios.

</DOC>
<DOC>
<DOCNO> 70734 </DOCNO>
epsilon'/epsilon and Rare K Decays in the Standard Model and


  After briefly reviewing the status of epsilon'/epsilon in the Standard Model,
I discuss SUSY contributions to epsilon'/epsilon, K^+ to pi^+ nu bar nu, K_L to
pi^0 nu bar nu and K_L to pi^0 e^+ e^-. While in the simplest case of the MSSM
with Minimal Flavour Violation the main effect is a suppression of these
transitions with respect to the Standard Model, large enhancements are possible
in more general SUSY models, with interesting correlations among the different
processes.

</DOC>
<DOC>
<DOCNO> 179007 </DOCNO>
Equilibration and freeze-out in an exploding system


  We use a simple gas model to study non-equilibrium aspects of the
multiparticle dynamics relevant to heavy ion collisions. By performing
numerical simulations for various initial conditions we identify several
characteristic features of the fast dynamics occurring in implosion-explosion
like processes.

</DOC>
<DOC>
<DOCNO> 117850 </DOCNO>
Near-Infrared Classification Spectroscopy: J-Band Spectra of Fundamental


  We present a catalog of J-band spectra for 88 fundamental MK standard stars
observed at a resolving power of R ~ 3000. This contribution serves as a
companion atlas to the K-band spectra published by Wallace and Hinkle (1997)
and the H-band atlas of Meyer et al. (1998). We report data from 7400-9550 1/cm
(1.05-1.34 microns) for stars of spectral types O7-M6 and luminosity classes
I-V as defined in the MK system. In reducing these data, special care has been
taken to remove time-variable telluric features of water vapor. We identify
atomic and molecular indices which are both temperature and luminosity
sensitive that aid in the classification of stellar spectra in the J-band. In
addition to being useful in the classification of late-type stars, the J-band
contains several features of interest in the study of early-type stellar
photospheres. These data are available electronically for anonymous FTP in
addition to being served on the World Wide Web.

</DOC>
<DOC>
<DOCNO> 101378 </DOCNO>
A Conditional Quasi-greedy Basis of l_1


  We show that the Lindenstrauss basic sequence in l_1 may be used to construct
a conditional quasi-greedy basis of l_1, thus answering a question of
Wojtaszczyk. We further show that the sequence of coefficient functionals for
this basis is not quasi-greedy.

</DOC>
<DOC>
<DOCNO> 123198 </DOCNO>
Search for a TeV gamma-ray halo of Mkn 501


  For distant extragalactic sources of gamma-rays in the PeV energy range,
interactions of the gamma rays with intergalactic diffuse radiation fields will
initiate a pair cascade. Depending on the magnetic fields in the vicinity of
the source, the cascade can either result in an isotropic halo around an
initially beamed source, or remain more or less collimated. Data recorded by
the HEGRA system of imaging atmospheric Cherenkov telescopes are used to derive
limits on the halo flux from the AGN Mrk 501. This is achieved by comparing the
angular distribution of TeV gamma-rays during the 1997 burst phase -- where
direct photons should dominate -- with the distribution during the 1998/99
quiescent state, where a steady-state halo contribution should be most
pronounced. The results depend on the assumptions concerning the angular
distribution of the halo; limits on the halo flux within 0.5 to 1 degr. from
the source range between 0.1% and 1% of the peak burst flux.

</DOC>
<DOC>
<DOCNO> 70813 </DOCNO>
A vorton gun


  In about half of all near-cusp events in superconducting cosmic strings with
chiral currents (and probably with general currents as well), the string
intersects itself near the cusp. Intercommutation causes the conversion of the
string near the cusp into a vorton (in the chiral case) with very high Lorentz
boost. We demonstrate how to analyze the cusp shape in a Lorentz frame that
makes the motion simple, by the use of a 5-dimensional procedure, and analyze
the resulting production of vortons.

</DOC>
<DOC>
<DOCNO> 170138 </DOCNO>
Construction of a Scalable, Uniform and Universal Quantum Network and


  We present a possible candidate of construction of a scalable, uniform and
universal quantum network, which is built from quantum gates to elements of
quantum circuit, again to quantum subnetworks and finally to an entire quantum
network. Our scheme can overcome some difficulties of the existing schemes and
makes improvements to different extent in the scale of quantum network, ability
of computation, implementation of engineering, efficiency of quantum network,
universality, compatibility, design principle, programmability, fault
tolerance, error control, industrialization and commercialization {\it et. al}
aspects. As the applications of this construction scheme, we obtain the entire
quantum networks for Shor's algorithm, Grover's algorithm and solving
Schr\"odinger equation in general. This implies that the scalable, uniform and
universal quantum networks are able to generally describe the known main
results and can be further applied to more interesting examples in quantum
computations.

</DOC>
<DOC>
<DOCNO> 121488 </DOCNO>
Redshift space bias and beta from the halo model


  We analyze scale dependence of redshift space bias $b$ and $\beta \equiv
\Omega_m^{0.6}/b$ in the context of the halo model. We show that linear bias is
a good approximation only on large scales, for $k<0.1h$Mpc$^{-1}$. On
intermediate scales the virial motions of the galaxies cause a suppression of
the power spectrum relative to the linear one, which differs from the same
effect in dark matter. This suppression can potentially mimic the effect of
massive neutrinos and the degeneracy can only be broken if the power spectrum
is measured for $k \ll 0.1h$Mpc$^{-1}$. Different methods to determine $\beta$
converge for $k<0.1h$Mpc$^{-1}$, but give drastically different results on
smaller scales, which explains some of the trends observed in the real data. We
also asses the level of stochasticity by calculating the cross-correlation
coefficient between the reconstructed velocity field divergence and the
galaxies and show that the two fields decorrelate for $k>0.1h$Mpc$^{-1}$. Most
problematic are galaxies predominantly found in groups and clusters, such as
bright, red or elliptical galaxies, where we find poor convergence to a
constant bias or $\beta$ even on large scales.

</DOC>
<DOC>
<DOCNO> 151996 </DOCNO>
On the Integrability of Covariant Field Theory for Open N=2 Strings


  We discuss the integrability of the Berkovits-Siegel open string field
equations and derive an infinite set of their non-local (solution-generating)
symmetries. The string field equations are embedded in an infinite system of
overdetermined equations (BS hierarchy) associated with hidden string
symmetries. The latter enforce the vanishing of most scattering amplitudes for
the open N=2 string.

</DOC>
<DOC>
<DOCNO> 119303 </DOCNO>
The Nuclear Dynamics of M32. I. Data and Stellar Kinematics


  We have obtained optical long-slit spectroscopy of the nucleus of M32 using
the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope. The
stellar rotation velocity and velocity dispersion, as well as the full
line-of-sight velocity distribution (LOSVD), were determined as a function of
position along the slit using two independent spectral deconvolution
algorithms. We see three clear kinematical signatures of the nuclear black
hole: a sudden upturn, at ~0.3 arc seconds from the center, in the stellar
velocity dispersions; a flat or rising rotation curve into the center; and
strong, non-Gaussian wings on the central LOSVD. The central velocity
dispersion is ~130 km/s (Gaussian fit) or ~175 km/s (corrected for the wings).
Both the velocity dispersion spike and the shape of the central LOSVD are
consistent with the presence of a supermassive compact object in M32 with a
mass in the range 2-5 x 10^6 solar masses. These data are a significant
improvement on previous stellar kinematical data, making M32 the first galaxy
for which the imprint of the black hole's gravitation on the stellar velocities
has been observed with a resolution comparable to that of gas-dynamical
studies.

</DOC>
<DOC>
<DOCNO> 100397 </DOCNO>
Extensions of Lie algebras


  We study (non-abelian) extensions of a given Lie algebra, identify a
cohomological obstruction to the existence, and interpret it in terms of the
Hochschild-Serre spectral sequence. A striking analogy to the setting of
covariant exterior derivatives, curvature, and the Bianchi identity in
differential geometry is spelled out. In the new version references added: Most
of the results are known. So this paper will not be submitted to a journal, it
can be regarded as a review paper.

</DOC>
<DOC>
<DOCNO> 170811 </DOCNO>
Remarks on Lewenstein-Sanpera Decomposition


  We discuss in this letter Lewenstein-Sanpera (L-S) decomposition for a
specific Werner state. Compared with the optimal case, we propose a
quasi-optimal one which in the view of concurrence leads to the same
entanglement measure for the entangled mixed state discussed. We think that in
order to obtain entanglement of given state the optimal L-S decomposition is
not necessary.

</DOC>
<DOC>
<DOCNO> 40352 </DOCNO>
Search for Neutral Supersymmetric Higgs Bosons in $p\bar{p}$ Collisions


  We present the results of a search for neutral Higgs bosons produced in
association with $b$ quarks in $p\bar{p}\to b\bar{b} \phi\to b\bar{b}b\bar{b}$
final states with $91 \pm 7$ pb$^{-1}$ of $p\bar{p}$ collisions at
$\sqrt{s}=1.8$ TeV recorded by the Collider Detector at Fermilab. We find no
evidence of such a signal and the data is interpreted in the context of the
neutral Higgs sector of the Minimal Supersymmetric extension of the Standard
Model. With basic parameter choices for the supersymmetric scale and the stop
quark mixing, we derive 95% C.L. lower mass limits for neutral Higgs bosons for
$\tb$ values in excess of 35.

</DOC>
<DOC>
<DOCNO> 102311 </DOCNO>
Hilbert modules over locally C*-algebras


  In the present paper the notion of a Hilbert module over a locally C*-algebra
is discussed and some results are obtained on this matter. In particular, we
give a detailed proof of the known result that the set of adjointable
endomorphisms of such modules is itself a locally C*-algebra.

</DOC>
<DOC>
<DOCNO> 178769 </DOCNO>
Supersymmetric Transformations in Coupled-Channel Systems


  A transformation of supersymmetric quantum mechanics for N coupled channels
is presented, which allows the introduction of up to N degenerate bound states
without altering the remaining spectrum of the Hamiltonian. Phase equivalence
of the Hamiltonian can be restored by two successive supersymmetric
transformations at the same energy. The method is successfully applied to the
3S1-3D1 coupled channels of the nucleon-nucleon system and a set of Moscow-type
potentials is thus generated.

</DOC>
<DOC>
<DOCNO> 118838 </DOCNO>
Temperature Profiles of Accretion Disks around Rapidly Rotating Neutron


  We calculate the temperature profiles of (thin) accretion disks around
rapidly rotating neutron stars (with low surface magnetic fields), taking into
account the full effects of general relativity. We then consider a model for
the spectrum of the X-ray emission from the disk, parameterized by the mass
accretion rate, the color temperature and the rotation rate of the neutron
star. We derive constraints on these parameters for the X-ray source Cygnus X-2
using the estimates of the maximum temperature in the disk along with the disk
and boundary layer luminosities, using the spectrum inferred from the EXOSAT
data. Our calculations suggest that the neutron star in Cygnus X-2 rotates
close to the centrifugal mass-shed limit. Possible constraints on the neutron
star equation of state are also discussed.

</DOC>
<DOC>
<DOCNO> 10773 </DOCNO>
Surface scaling behavior of isotropic Heisenberg systems: Critical


  The surface scaling behavior of classical isotropic Heisenberg magnets is
investigated by Monte - Carlo methods in d=3 dimensions for various values of
the surface - to - bulk coupling ratio J_1/J. For J_1/J <= 1.0 critical
behavior according to the ordinary surface universality class is found. New
estimates for magnetic surface exponents are presented and compared to older
estimates and their theoretical counterparts. For J_1/J >= 2.0 scaling is still
valid with effective exponents which depend on J_1/J. The surface structure
factor S_1(p,L) is investigated at bulk criticality as function of the momentum
transfer p parallel to the surface and the system size L. For J_1/J <= 1.0 and
J_1/J >= 2.0 the full p dependence of S_1(p,L) can be captured by generalized
shape functions to a remarkable accuracy. Profiles of the magnetization and the
energy density also confirm scaling, where for J_1/J <= 1.0 the ordinary
surface universality class is recovered and for J_1/J >= 2.0 scaling with J_1/J
dependent exponents is found. For J_1/J = 1.5 the system displays a striking
crossover behavior from spurious long - range surface order to the ordinary
surface universality class. For J_1/J >= 2.0 the effective scaling laws must be
interpreted as nonasymptotic and the value J_1/J = 1.5 marks a crossover
regime, in which the crossover from the nonasymptotic to the asymptotic
(ordinary) surface scaling behavior can be resolved within numerically
attainable system sizes.

</DOC>
<DOC>
<DOCNO> 69225 </DOCNO>
Limits on the Mass of a Composite Higgs Boson


  We discuss the bound on the mass of the Higgs boson arising from precision
electroweak measurements in the context of the triviality of the scalar Higgs
model. We show that, including possible effects from the underlying nontrivial
dynamics, a Higgs boson mass of up to 500 GeV is consistent with current data.

</DOC>
<DOC>
<DOCNO> 100992 </DOCNO>
Obstructions to nonnegative curvature and rational homotopy theory


  We establish a link between rational homotopy theory and the problem which
vector bundles admit complete Riemannian metric of nonnegative sectional
curvature. As an application, we show for a large class of simply-connected
nonnegatively curved manifolds that, if C lies in the class and T is a torus of
positive dimension, then ``most'' vector bundles over the product of C and T
admit no complete nonnegatively curved metric.

</DOC>
<DOC>
<DOCNO> 122377 </DOCNO>
Search for Discrete Refractive Scattering Events


  We have searched for discrete refractive scattering events (including effects
due to possible non-multiple diffractive scattering) at meter wavelengths in
the direction of two close by pulsars B0950+08 and B1929+10, where we looked
for spectral signatures associated with the multiple imaging of pulsars due to
scattering in the interstellar medium. We do not find any signatures of such
events in the direction of either source over a spectral periodicity range of
50 KHz to 5 MHz. Our analysis puts strong upper limits on the column density
contrast associated with a range of spatial scales of the interstellar electron
density irregularities along these lines of sight.

</DOC>
<DOC>
<DOCNO> 84635 </DOCNO>
A Conserved Energy Integral for Perturbation Equations in the Kerr-de


  The analytic proof of mode stability of the Kerr black hole was provided by
Whiting. In his proof, the construction of a conserved quantity for unstable
mode was crucial. We extend the method of the analysis for the Kerr-de Sitter
geometry. The perturbation equations of massless fields in the Kerr-de Sitter
geometry can be transformed into Heun's equations which have four regular
singularities. In this paper we investigate differential and integral
transformations of solutions of the equations. Using those we construct a
conserved quantity for unstable modes in the Kerr-de Sitter geometry, and
discuss its property.

</DOC>
<DOC>
<DOCNO> 102822 </DOCNO>
$L_h^2$-domains of holomorphy and the Bergman kernel


  We give a characterization of $L_h^2$-domains of holomorphy with the help of
the boundary behavior of the Bergman kernel and geometric properties of the
boundary, respectively.

</DOC>
<DOC>
<DOCNO> 152576 </DOCNO>
Stable non-BPS D-branes and their classical description


  We review how to describe the stable non-BPS D-branes of type II string
theory from a classical perspective, and discuss the properties of the
space-time geometry associated to these configurations. This is relevant in
order to see whether and how the gauge/gravity correspondence can be formulated
in non-conformal and non-supersymmetric settings.

</DOC>
<DOC>
<DOCNO> 10060 </DOCNO>
Equation of state and critical behavior of polymer models: A


  We present an application of Wertheim's Thermodynamic Perturbation Theory
(TPT1) to a simple coarse grained model made of flexibly bonded Lennard-Jones
monomers. We use both the Reference Hyper-Netted-Chain (RHNC) and Mean
Spherical approximation (MSA) integral equation theories to describe the
properties of the reference fluid. The equation of state, the density
dependence of the excess chemical potential, and the critical points of the
liquid--vapor transition are compared with simulation results and good
agreement is found. The RHNC version is somewhat more accurate, while the MSA
version has the advantage of being almost analytic. We analyze the scaling
behavior of the critical point of chain fluids according to TPT1 and find it to
reproduce the mean field exponents: The critical monomer density is predicted
to vanish as $n^{-1/2}$ upon increasing the chain length $n$ while the critical
temperature is predicted to reach an asymptotic finite temperature that is
attained as $n^{-1/2}$. The predicted asymptotic finite critical temperature
obtained from the RHNC and MSA versions of TPT1 is found to be in good
agreement with the $\Theta$ point of our polymer model as obtained from the
temperature dependence of the single chain conformations.

</DOC>
<DOC>
<DOCNO> 10909 </DOCNO>
Superfluid Transition Temperature in a Fermi Gas with Repulsion. Higher


  High order perturbation theory corrections to the superfluid transition
temperature in a weakly interacting Fermi gas with repulsive interaction are
calculated. This involves calculating the contributions of third and fourth
order diagrams in the gas parameter and taking into account effects of
retardation. The contributions from both second, third and fourth orders result
in the effective attraction in p-wave channel. It is shown that the critical
temperature is mainly determined by second and third orders terms of
perturbation theory. The dependence of the critical temperature on an external
magnetic field is found. We discuss possible applications of the results to the
diluted 3He-4He mixtures and trapped neutral-atom Fermi gases.

</DOC>
<DOC>
<DOCNO> 70039 </DOCNO>
Continuum Strong QCD: Confinement and Dynamical Chiral Symmetry Breaking


  Continuum strong QCD is the application of models and continuum quantum field
theory to the study of phenomena in hadronic physics, which includes; e.g., the
spectrum of QCD bound states and their interactions. Herein I provide a
Dyson-Schwinger equation perspective, focusing on qualitative aspects of
confinement and dynamical chiral symmetry breaking in cold, sparse QCD, and
also elucidating consequences of the axial-vector Ward-Takahashi identity and
features of the heavy-quark limit.

</DOC>
<DOC>
<DOCNO> 102797 </DOCNO>
Commutators in mapping class groups and bounded cohomology


  We prove that the stable commutator lengths of Dehn twists are positive,
implying that the natural map from the second bounded cohomology to the
ordinary cohomology is not injective, that mapping class groups are not
uniformly perfect and that the growth rate of Dehn twists are linear. We then
prove that the dimensions of the second bounded cohomology of hyperelliptic
mapping class groups and of the mapping class groups of surfaces of genus at
most two are equal to the cardinal of the continuum. For any positive integer
$n$, we exhibit a subgroup $G_n$ of the mapping class group of a surface of
genus two such that $G_n$ does not contain the Torelli group and the rank of
its first cohomology is at least $n$.

</DOC>
<DOC>
<DOCNO> 120729 </DOCNO>
Carbon Star Survey of Local Group Dwarf Galaxies. II. Pegasus, DDO 210


  We present the latest results of our ongoing four filter photometric survey
of C stars in Local Group dwarf irregular galaxies. Observations of the two low
luminosity dwarf irregular galaxies, Pegasus and DDO 210, revealed respectively
40 and 3 C stars, assuming that the reddening of Pegasus is negligible. No C
stars were identified in Tucana. Our observations permit the estimation of the
CMD contamination by foreground M dwarf thus yielding reliable C/M ratios. Our
R, I photometry of the C stars cannot be used to solve the extinction
controversy toward Pegasus. The three C stars in DDO 210 are quite bright when
compared to C star populations in dwarf galaxies. A larger fainter population
in that galaxy seems however improbable. The statistics of C stars, currently
on hand for dwarf galaxies, show a well-defined trend with the absolute
magnitude of galaxies.

</DOC>
<DOC>
<DOCNO> 118560 </DOCNO>
The only non-contradictory model of universe


  The Friedmann equations of universe dynamics describe the infinite number of
the Friedmannian models of universe. The consistent and distinguished
relativistic, classical-mechanical, quantum-mechanical and formal-logical
analysis of the Friedmannian universe models leads to a surprising and
unexpected conclusion: The Friedmannian model of the flat expansive homogeneous
and isotropic universe with the zero gravitational force state equation is the
only model of universe, which does not contradict the: 1st Einstein general
theory of relativity (and its special partial solutions: the Einstein special
theory of relativity and the Newton theory of gravitation); 2nd quantum
mechanics; 3rd fundamental formal principles of logical thinking; and 4th
observations.

</DOC>
<DOC>
<DOCNO> 9338 </DOCNO>
Remark on "Conductance and Shot Noise for Particles with Exclusion


  Isakov, Martin, and Ouvry [PRL 83, 580 (1999)] have recently proposed a fresh
approach to the potential observation of fractional exclusion statistics.
According to their argument, a clear signature of fractional statistics should
exist in the shot noise of a Luttinger fluid, an ideal system postulated by
some to underlie the well-founded Laughlin quasiparticle states of the
two-dimensional electron gas. We elaborate on some delicate points made by
Isakov et al. and reflect upon the relationship between this novel intuitive
scheme and certain old issues of first principles.

</DOC>
<DOC>
<DOCNO> 7976 </DOCNO>
Electric Field Induced Phase Transition in KDP Crystal Near Curie Point:


  X-ray scattering measurements are performed in order to verify % that the
mechanism leading to the DC electric field induced $C_{2v}^{19} \to
C_{2v}^{\neq 19}$ phase transition in KDP crystal at 119 K is the changing of
the local sites symmetries of phosphate group from $C_2$ in the $C_{2v}^{19}$
phase to $C_s$ in the $C_{2v}^{\neq 19}$ phase. It is shown by analyzing the
integrated intensity of the (800) and (080) reflections that under DC electric
field the density of oxygen atoms lying on these plane changes indicating that
phosphate group rotates around the [010] direction relative to the orthorhombic
$C_{2v}^{19}$ structure. Some Raman results are also discussed.

</DOC>
<DOC>
<DOCNO> 100828 </DOCNO>
Arakelov intersection indices of linear cycles and the geometry of


  This paper generalizes Manin's approach towards a geometrical interpretation
of Arakelov theory at infinity to linear cycles on projective spaces. We show
how to interpret certain non-Archimedean Arakelov intersection numbers of
linear cycles on $P^{n-1}$ with the combinatorial geometry of the Bruhat-Tits
building associated to PGL(n). This geometric setting has an Archimedean
analogue, namely the Riemannian symmetric space associated to SL(n,C), which we
use to interpret analogous Archimedean intersection numbers of linear cycles in
a similar way.

</DOC>
<DOC>
<DOCNO> 9068 </DOCNO>
Density of States of Disordered Two-Dimensional Crystals with


  A diagrammatic method is applied to study the effects of commensurability in
two-dimensional disordered crystalline metals by using the particle-hole
symmetry with respect to the nesting vector P_0={\pm{\pi}/a, {\pi}/a} for a
half-filled electronic band. The density of electronic states (DoS) is shown to
have nontrivial quantum corrections due to both nesting and elastic impurity
scattering processes, as a result the van Hove singularity is preserved in the
center of the band. However, the energy dependence of the DoS is strongly
changed. A small offset from the middle of the band gives rise to disappearence
of quantum corrections to the DoS .

</DOC>
<DOC>
<DOCNO> 119799 </DOCNO>
Measuring Supernova Neutrino Temperatures using Lead Perchlorate


  Neutrino interactions with lead produce neutrons in numbers that depend on
neutrino energy and type. A detector based on lead perchlorate, for example,
would be able to measure the energy deposited by electrons and gammas in
coincidence with the number of neutrons produced. Sorting the electron energy
spectra by the number of coincident neutrons permits the identification of the
neutrino type that induced the reaction. This separation allows an analysis
which can determine the temperatures of electron neutrinos and electron
anti-neutrinos from a supernova in one experiment. The neutrino reaction
signatures of lead perchlorate and the fundamentals of using this material as a
neutrino detector are described.

</DOC>
<DOC>
<DOCNO> 99675 </DOCNO>
On cocycles with values in the group SU(2)


  In this paper we introduce the notion of degree for $C^1$-cocycles over
irrational rotations on the circle with values in the group SU(2). It is shown
that if a $C^1$-cocycle $\phi:S^1\to SU(2)$ over an irrational rotation by
$\alpha$ has nonzero degree, then the skew product $S^1\times
SU(2)\ni(x,g)\mapsto (x+\alpha,g\phi(x))\in S^1\times SU(2)$ is not ergodic and
the group of essential values of $\phi$ is equal to the maximal Abelian
subgroup of SU(2). Moreover, if $\phi$ is of class $C^2$ (with some additional
assumptions) the Lebesgue component in the spectrum of the skew product has
countable multiplicity. Possible values of degree are discussed, too.

</DOC>
<DOC>
<DOCNO> 67947 </DOCNO>
Introduction to B Physics


  These lectures provide an introduction to various topics in heavy-flavor
physics. We review the theory and phenomenology of heavy-quark symmetry,
exclusive weak decays of $B$ mesons, inclusive decay rates, and some rare $B$
decays.

</DOC>
<DOC>
<DOCNO> 69636 </DOCNO>
Renormalisation Group Analysis of Single Right-handed Neutrino Dominance


  We perform a renormalisation group (RG) analysis of neutrino masses and
mixing angles in the see-saw mechanism in the minimal supersymmetric standard
model with three right-handed neutrinos, including the effects of the heavy
neutrino thresholds. We focus on the case that one of the right-handed
neutrinos provides the dominant contribution to the 23 block of the light
Majorana matrix, causing its determinant to approximately vanish and giving an
automatic neutrino mass hierarchy, so called single right-handed neutrino
dominance which may arise from a U(1) family symmetry. In these models
radiative corrections can increase atomospheric and solar neutrino mixing by up
to about 10% and 5%, respectively, and may help to achieve bi-maximal mixing.
Significantly we find that the radiative corrections over the heavy neutrino
threshold region are at least as important as those usually considered from the
lightest right-handed neutrino down to low energies.

</DOC>
<DOC>
<DOCNO> 10654 </DOCNO>
Continuous quantum measurement of two coupled quantum dots using a point


  We obtain the finite-temperature unconditional master equation of the density
matrix for two coupled quantum dots (CQD) when one dot is subjected to a
measurement of its electron occupation number using a point contact (PC). To
determine how the CQD system state depends on the actual current through the PC
device, we use the so-called quantum trajectory method to derive the
zero-temperature conditional master equation. We first treat the electron
tunneling through the PC barrier as a classical stochastic point process (a
quantum-jump model). Then we show explicitly that our results can be extended
to the quantum-diffusive limit when the average electron tunneling rate is very
large compared to the extra change of the tunneling rate due to the presence of
the electron in the dot closer to the PC. We find that in both quantum-jump and
quantum-diffusive cases, the conditional dynamics of the CQD system can be
described by the stochastic Schr\"{o}dinger equations for its conditioned state
vector if and only if the information carried away from the CQD system by the
PC reservoirs can be recovered by the perfect detection of the measurements.

</DOC>
<DOC>
<DOCNO> 120381 </DOCNO>
Rotating compact strange stars


  We compute numerical models of uniformly rotating strange stars (SS) in
general relativity for the recently proposed QCD-based equation of state (EOS)
of strange quark matter (Dey et al. 1998). Static models based on this EOS are
characterised by a larger surface redshift than strange stars within the MIT
bag model. The frequencies of the fastest rotating configurations described by
Dey model are much higher than these for neutron stars (NS) and for the
simplest SS MIT bag model. We determine a number of physical parameters for
such stars and compare them with those obtained for NS. We construct constant
baryon mass equilibrium sequences both normal and supramassive. Similarly to
the NS a supramassive SS, prior to collapse to a black hole, spins up as it
loses angular momentum. We find the upper limits on maximal masses and maximal
frequencies of the rotating configurations. We show that the maximal rotating
frequency for each of considered evolutionary sequences is never the Keplerian
one. A normal and low mass supramassive strange stars gaining angular momentum
always slows down just before reaching the Keplerian limit. For a high mass
supramassive SS sequence the Keplerian configuration is the one with the lowest
rotational frequency in the sequence. The value of $T/W$ for rapidly rotating
SS of any mass is significantly higher than those for ordinary NS. For
Keplerian configurations it increases as mass decreases. The results are robust
for all linear self-bound equations of state.

</DOC>
<DOC>
<DOCNO> 68159 </DOCNO>
Spin effects in the fragmentation of a transversely polarized quark


  An azimuthal dependence of pions produced in polarized Deep Inelastic
Scattering, gamma^* - p(transv. polarized) -> pion + X, has been recently
observed and might be related to the so-called Collins effect. We discuss in
details, for a general spin configuration of the nucleon, the kinematics of the
process and methods of extracting information on the fragmentation properties
of a polarized quark. Assuming that the observed azimuthal dependence is indeed
due to Collins effect, we derive a lower bound estimate for the size of the
quark analysing power, which turns out to be large.

</DOC>
<DOC>
<DOCNO> 69332 </DOCNO>
Scale Factor in Double Parton Collisions and Parton Densities in


  The scale factor $\sigma_{eff}$, which characterizes double parton collisions
in high energy hadron interactions, is a direct manifestation of the
distribution of the interacting partons in transverse space, in such a way that
different distributions give rise to different values of $\sigma_{eff}$ in
different double parton collision processes. We work out the value of the scale
factor in a few reactions of interest, in a correlated model of the
multi-parton density of the proton recently proposed.

</DOC>
<DOC>
<DOCNO> 9603 </DOCNO>
Stochastic System with Colored Noise and Absorbing States: Path Integral


  The behavior of the most probable values of the order parameter $x$ and the
amplitude $\phi$ of conjugate force fluctuations is studied for a stochastic
system with a colored multiplicative noise with absorbing states. The phase
diagrams introduced as dependencies the noise self-correlation time vs
temperature and noise growth velocity are defined. It is shown that phase
half-plane $(x,\phi)$ can be split into isolated domains of large,
intermediate, and small values of $x$. System behavior in these domains is
studied by the probability represented as path integral. In the region $x\ll
1$, the trajectories converge to the point $x = \phi = 0$ for $0 < a < 1/2$ and
to $x = 0$, $\phi\to\infty$ for $1/2 < a \le 1$. In the former case, the
probability of realization of trajectories is finite, while in the latter case
it is vanishingly small, and an absorbing state can be formed.

</DOC>
<DOC>
<DOCNO> 120628 </DOCNO>
Satellite observations of thought experiments close to a black hole


  Since black holes are `black', methods of their identification must
necessarily be indirect. Due to very special boundary condition on the horizon,
the advective flow behaves in a particular way, which includes formation of
centrifugal pressure dominated boundary layer or CENBOL where much of the
infall energy is released and outflows are generated. The observational aspects
of black holes must depend on the steady and time-dependent properties of this
boundary layer. Several observational results are written down in this review
which seem to support the predictions of thought experiments based on this
advective accretion/outflow model. In future, when gravitational waves are
detected, some other predictions of this model could be tested as well.

</DOC>
<DOC>
<DOCNO> 80703 </DOCNO>
Unquenched Charmonium with NRQCD


  We present the results from a series of lattice simulations of the charmonium
system using a highly-improved NRQCD action, both in the quenched
approximation, and with n_f = 2 light dynamical quarks. The spectra show some
evidence for quenching effects of roughly 10% in the S- and P-hyperfine spin
splittings---probably too small to account for the severe underestimates in
these quantities seen in previous quenched charmonium simulations. We also find
estimates for the magnitude of other systematic effects---in particular, the
choice of the tadpole factor can alter spin splittings at the 10-20% level, and
radiative corrections may be as large as 40% for charmonium. We conclude that
quenching is just one of a collection of important effects that require
attention in precision heavy-quark simulations.

</DOC>
<DOC>
<DOCNO> 102485 </DOCNO>
Local Cohomology, Arrangement of Subspaces and Monomial Ideals


  Let $k$ be a field of characteristic zero and I an ideal defining an
arrangement of linear subspaces in the affine space $A^n_k$. We compute the
D-module theoretic characteristic cycle of the local cohomology modules
$H^r_I(k[x_1,...,x_n])$ in terms of the poset defined by the arrangement. In
case I is a monomial ideal, we relate the multiplicities of the characteristic
cycle with the Betti numbers of the Alexander dual ideal of I, we also study
some extension problems attached to the modules $H^r_I(k[x_1,...,x_n])$. If $k$
is the field of complex numbers we study the ubiquity of these local cohomology
modules in the category of perverse sheaves in $A^n_k$ with respect to the
stratification given by the coordinate hyperplanes.

</DOC>
<DOC>
<DOCNO> 122569 </DOCNO>
The distance modulus of the Large Magellanic Cloud based on double-mode


  We use double-mode RR Lyrae (RRd) stars from the MACHO variable star database
of the Large Magellanic Cloud (LMC) to estimate its distance, by utilizing
photometric data, linear pulsation and stellar atmosphere models. If we set
E_(B-V)=0.11 and [M/H]=-1.5 for LMC, we get M-m=18.52 mag, which is in
agreement with the value obtained from Galactic cluster RRd stars. Although the
formal statistical error (standard deviation) of M-m derived from the MACHO set
is only 0.024 mag, the systematic errors are more substantial. These errors are
mostly due to the zero point ambiguity of the temperature scale and to the
error of the photometric calibration. However, the fact that the distance
moduli obtained in this and in our former studies of cluster RRd and Small
Magellanic Cloud beat Cepheids agree so well, implies that the only serious
source of error is the zero point of the temperature scale, which should not
have larger than +/-0.10 mag effect on the distance modulus.

</DOC>
<DOC>
<DOCNO> 12543 </DOCNO>
Phase separation frustrated by the long range Coulomb interaction I:


  We analyze the combined effect of the long range Coulomb (LRC) interaction
and of surface energy on first order density-driven phase transitions in the
presence of a compensating rigid background. We study mixed states formed by
regions of one phase surrounded by the other in the case in which the scale of
the inhomogeneities is much larger than the interparticle distance. Two
geometries are studied in detail: spherical drops of one phase into the other
and a layered structure of one phase alternating with the other. We find the
optimum density profile in an approximation in which the free energy is a
functional of the local density (LDA). It is shown that an approximation in
which the density is assumed to be uniform (UDA) within each phase region gives
results very similar to those of the more involved LDA approach. Within the UDA
we derive the general equations for the chemical potential and the pressures of
each phase which generalize the Maxwell construction to this situation. The
equations are valid for a rather arbitrary geometry. We find that the
transition to the mixed state is quite abrupt i.e. inhomogeneities of the first
phase appear with a finite value of the radius and of the phase volume
fraction. The maximum size of the inhomogeneities is found to be on the scale
of a few electric field screening lengths. Contrary to the ordinary Maxwell
construction, the inverse specific volume of each phase depends here on the
global density in the coexistence region and can decrease as the global density
increases. The range of densities in which coexistence is observed shrinks as
the LRC interaction increases until it reduces to a singular point. We argue
that close to this singular point the system undergoes a lattice instability as
long as the inverse lattice compressibility is finite.

</DOC>
<DOC>
<DOCNO> 68678 </DOCNO>
Charm Estimate from the Dilepton Spectra


  A validity of a recent estimate of an upper limit of charm production in
central Pb+Pb collisions at 158 AGeV is critically discussed. Within a simple
model we study properties of the background subtraction procedure used for an
extraction of the charm signal from the analysis of dilepton spectra. We
demonstrate that a production asymmetry between positively and negatively
charged background muons and a large multiplicity of signal pairs leads to
biased results. Therefore the applicability of this procedure for the analysis
of nucleus-nucleus data should be reconsidered before final conclusions on the
upper limit estimate of charm production could be drawn.

</DOC>
<DOC>
<DOCNO> 84098 </DOCNO>
On cosmological perturbations in FRW model with scalar field and false


  The unconstrained reduced action corresponding to the dynamics of scalar
fluctuations about the Friedmann-Robertson-Walker (FRW) background is derived
using Dirac's method of description of singular Lagrangian systems. The results
are applied to so-called negative mode problem in description of tunneling
transitions with gravity. With our special choice of physical variable, the
kinetic term of the reduced action has a conventional signature for a wide
class of models. In this representation, the existence of a negative mode
justifying the false vacuum decay picture turns out to be manifest. We also
explain how the present result becomes consistent with the previously proved
``no negative mode (supercritical supercurvature mode) theorem''.

</DOC>
<DOC>
<DOCNO> 8121 </DOCNO>
Disorder and Interaction in 2D: Exact diagonalization study of the


  We investigate, by numerically calculating the charge stiffness, the effects
of random diagonal disorder and electron-electron interaction on the nature of
the ground state in the 2D Hubbard model through the finite size exact
diagonalization technique. By comparing with the corresponding 1D Hubbard model
results and by using heuristic arguments we conclude that it is
\QTR{it}{unlikely} that there is a 2D metal-insulator quantum phase transition
although the effect of interaction in some range of parameters is to
substantially enhance the non-interacting charge stiffness.

</DOC>
<DOC>
<DOCNO> 12762 </DOCNO>
Angular Dependence of the Upper Critical Field in Triplet


  Assuming that the order parameter corresponds to an equal spin triplet
pairing state, we calculate the angular dependence of the upper critical field
in triplet quasi-one-dimensional superconductors at high magnetic fields
applied alongthe yz plane

</DOC>
<DOC>
<DOCNO> 150840 </DOCNO>
Derivatives and the Role of the Drinfel'd Twist in Noncommutative String


  We consider the derivatives which appear in the context of noncommutative
string theory. First, we identify the correct derivations to use when the
underlying structure of the theory is a quasitriangular Hopf algebra. Then we
show that this is a specific case of a more general structure utilising the
Drinfel'd twist. We go on to present reasons as to why we feel that the
low-energy effective action, when written in terms of the original commuting
coordinates, should explicitly exhibit this twisting.

</DOC>
<DOC>
<DOCNO> 122745 </DOCNO>
Search for Gamma Ray Bursts at Chacaltaya


  A search for Gamma Ray Bursts in the GeV-TeV energy range has been performed
by INCA, an air shower array working at 5200 m of altitude at the Chacaltaya
Laboratory (Bolivia). The altitude of the detector and the use of the "single
particle technique" allows to lower the energy threshold up to few GeVs. No
significant signals are observed during the occurrence of 125 GRBs detected by
BATSE, and the obtained upper limits on the energy fluence in the interval
1-1000(100) GeV range from 3.2(8.6) 10^-5 to 2.6(7.0) 10^-2 erg/cm^2 depending
on the zenith angle of the events. These limits, thanks to the extreme altitude
of INCA, are the lowest ever obtained in the sub-TeV energy region by a ground
based esperiment.

</DOC>
<DOC>
<DOCNO> 13029 </DOCNO>
Dynamics of relaxor ferroelectrics


  We study a dynamic model of relaxor ferroelectrics based on the spherical
random-bond---random-field model and the Langevin equations of motion. The
solution to these equations is obtained in the long-time limit where the system
reaches an equilibrium state in the presence of random local electric fields.
The complex dynamic linear and third-order nonlinear susceptibilities
$\chi_1(\omega)$ and $\chi_3(\omega)$, respectively, are calculated as
functions of frequency and temperature. In analogy with the static case, the
dynamic model predicts a narrow frequency dependent peak in $\chi_3(T,\omega)$,
which mimics a transition into a glass-like state.

</DOC>
<DOC>
<DOCNO> 7958 </DOCNO>
Bogoliubov Renormalization Group and Symmetry of Solution in


  Evolution of the concept known in the theoretical physics as the
Renormalization Group (RG) is presented. The corresponding symmetry, that has
been first introduced in QFT in mid-fifties, is a continuous symmetry of a
solution with respect to transformation involving parameters (e.g., of boundary
condition) specifying some particular solution.
  After short detour into Wilson's discrete semi-group, we follow the expansion
of QFT RG and argue that the underlying transformation, being considered as a
reparameterisation one, is closely related to the self-similarity property. It
can be treated as its generalization, the Functional Self-similarity (FS).
  Then, we review the essential progress during the last decade of the FS
concept in application to boundary value problem formulated in terms of
differential equations. A summary of a regular approach recently devised for
discovering the RG = FS symmetries with the help of the modern Lie group
analysis and some of its applications are given.
  As a main physical illustration, we give application of new approach to
solution for a problem of self-focusing laser beam in a non-linear medium.

</DOC>
<DOC>
<DOCNO> 170336 </DOCNO>
Reply to Comment on "Counterfactual Entanglement and Nonlocal


  Two objections have been raised to the arguments presented in O. Cohen, Phys.
Rev. A 60, 80 (1999). It is pointed out that neither objection has anything
whatsoever to do with the main subject matter of that paper, and shown that
both objections are based on misunderstandings of the examples to which they
relate.

</DOC>
<DOC>
<DOCNO> 174504 </DOCNO>
Thermal bremsstrahlung probing the thermodynamical state of


  Inclusive and exclusive hard-photon (E$_\gamma >$ 30 MeV) production in five
different heavy-ion reactions ($^{36}$Ar+$^{197}$Au, $^{107}$Ag, $^{58}$Ni,
$^{12}$C at 60{\it A} MeV and $^{129}$Xe+$^{120}$Sn at 50{\it A} MeV) has been
studied coupling the TAPS photon spectrometer with several charged-particle
multidetectors covering more than 80% of 4$\pi$. The measured spectra, slope
parameters and source velocities as well as their target-dependence, confirm
the existence of thermal bremsstrahlung emission from secondary nucleon-nucleon
collisions that accounts for roughly 20% of the total hard-photon yield. The
thermal slopes are a direct measure of the temperature of the excited nuclear
systems produced during the reaction.

</DOC>
<DOC>
<DOCNO> 120446 </DOCNO>
Low and High Frequency Quasi-Periodic Oscillations in 4U1915-05


  The X-ray burster and dipper 4U1915-05 (also known as XB1916-053) was
observed 19 times for a total exposure of roughly 140 ks between 1996 February
and October with the proportional counter array (PCA) aboard Rossi X-ray Timing
Explorer (RXTE). We present here the detailed timing study of its X-ray
emission. The source was observed in both a high intensity/soft spectral and a
low intensity/hard spectral state. The 2-20 keV luminosities are about
1.4x10^37 and 3.2x10^36 ergs/s in the two regimes respectively (assuming a
source distance of 9.3 kpc). We confirm that 4U1915-05 is an atoll source based
on its spectral behaviour and its aperiodic variability in the frequency range
4x10^{-3}-128 Hz. 4U1915-05 displays red noise below 1 Hz, but is especially
remarkable for its quasi-periodic variability detected for the first time at
several timescales. We detect low frequency quasi-periodic oscillations
(LFQPOs) between 5 and 80 Hz, as well as high frequency QPOs (HFQPOs) between
200 and 1300 Hz. Both LFQPOs and HFQPOs frequencies positively correlate with
the mass accretion rate inferred from the position of the source on the
color-color diagram. In a narrow range of luminosity, we also detect twin
simultaneous HFQPOs separated by 348 +/- 12 Hz.

</DOC>
<DOC>
<DOCNO> 99427 </DOCNO>
Cyclic homology of commutative algebras over general ground rings


  We consider commutative algebras and chain DG algebras over a fixed
commutative ground ring $k$ as in the title. We are concerned with the problem
of computing the cyclic (and Hochschild) homology of such algebras via free
DG-resolutions $\Lambda V @>>> A$. We find spectral sequences
$$E^2_{p,q}=H_p(\Lambda V\otimes\Gamma^q(dV))\Rightarrow HH_{p+q}(\Lambda V)$$
and $${E'}^2_{\pq}=H_p(\Lambda V\otimes\Gamma^{\le q}(dV)) \Rightarrow
HC_{p+q}(\Lambda V)$$ The algebra $\Lambda V\otimes\Gamma(dV)$ is a divided
power version of the de Rham algebra; in the particular case when $k$ is a
field of characteristic zero, the spectral sequences above agree with those
found by Burghelea and Vigu\'e (Cyclic homology of commutative algebras I,
Lecture Notes in Math. {\bf 1318} (1988) 51-72), where it is shown they
degenerate at the $E^2$ term. For arbitrary ground rings we prove here (Theorem
2.3) that if $V_n=0$ for $n\ge 2$ then $E^2=E^\infty$. From this we derive a
formula for the Hochschild homology of flat complete intersections in terms of
a filtration of the complex for crystalline cohomology, and find a description
of ${E'}^2$ also in terms of crystalline cohomology (theorem 3.0). The latter
spectral sequence degenerates for complete intersections of embedding dimension
$\le 2$ (Corollary 3.1). Without flatness assumptions, our results can be
viewed as the computation Shukla (cyclic) homology (T. Pirashvili, F.
Waldhausen; Mac Lane homology and topological Hochschild homology, J. Pure
Appl. Algebra{\bf 82} (1992) 81-98).

</DOC>
<DOC>
<DOCNO> 122565 </DOCNO>
XTE J1550-564: A superluminal ejection during the September 1998


  In 1998 September, the X-ray transient XTE J1550-564 underwent a major
outburst in soft and hard X-rays, followed by a radio flare. Australian Long
Baseline Array images obtained shortly after the peak in the radio flare showed
evolving structure. The components observed have an apparent separation
velocity of >2c.

</DOC>
<DOC>
<DOCNO> 169666 </DOCNO>
Global Derivation of the Fluctuation Determinant from Group Property of


  The Van Vleck-Pauli-Morette fluctuation determinant is derived from the
global group property of the time evolution amplitude in a continuous
formulation of path integrals.

</DOC>
<DOC>
<DOCNO> 12421 </DOCNO>
Is there Ornstein-Zernike equation in the canonical ensemble?


  A general density-functional formalism using an extended variable-space is
presented for classical fluids in the canonical ensemble (CE). An exact
equation is derived that plays the role of the Ornstein-Zernike (OZ) equation
in the grand canonical ensemble (GCE). When applied to the ideal gas we obtain
the exact result for the total correlation function h_N. For a homogeneous
fluid with N particles the new equation only differs from OZ by 1/N and it
allows to obtain an approximate expression for h_N in terms of its GCE
counterpart that agrees with the expansion of h_N in powers of 1/N.

</DOC>
<DOC>
<DOCNO> 10745 </DOCNO>
Statistics of energy levels and eigenfunctions in disordered and chaotic


  The supersymmetry method has proven to be a very powerful tool of study of
the statistical properties of energy levels and eigenfunctions in disordered
and chaotic systems. The aim of these lectures is to present a tutorial
introduction to the method, as well as an overview of the recent developments.

</DOC>
<DOC>
<DOCNO> 100206 </DOCNO>
Embedding obstructions and 4-dimensional thickenings of 2-complexes


  The vanishing of Van Kampen's obstruction is known to be necessary and
sufficient for embeddability of a simplicial n-complex into $R^{2n}$ for $n\neq
2$, and it was recently shown to be incomplete for $n=2$. We use
algebraic-topological invariants of four-manifolds with boundary to introduce a
sequence of higher embedding obstructions for a class of 2-complexes in $R^4$.

</DOC>
<DOC>
<DOCNO> 121824 </DOCNO>
The Association of Jet Production with Geometrically Thick Accretion


  A model is presented in which the strongest radio-emitting jet outflows are
produced in black hole systems when the accretion is a geometrically thick
($H/R \sim 1$) inflow ({\it e.g.}, ADAF, CDAF) {\em and} if the black hole is
rotating. For galactic black hole candidates, the model naturally accounts for
the observed correlation of jet outflow with the black hole hard emission state
and predicts an association of strong jets with rapid black hole rotation. When
extended to the supermassive case, the model accounts for the highest radio
galaxy and quasar jet powers and provides additional theoretical support for
the ``spin paradigm'', which asserts that radio loud quasars are produced by
Kerr holes and radio quiet ones by Schwarzschild holes. In some cases, the
angular momentum and energy outflow in the jet may be large enough to
significantly alter the structure of the accretion flow from that predicted by
current models.

</DOC>
<DOC>
<DOCNO> 151604 </DOCNO>
Center vortex model for the infrared sector of Yang-Mills theory


  A model for the infrared sector of SU(2) Yang-Mills theory, based on magnetic
vortices represented by (closed) random surfaces, is presented. The random
surfaces, governed by an action penalizing curvature, are investigated using
Monte Carlo methods on a hypercubic lattice. A low-temperature confining phase
and a high-temperature deconfined phase are generated by this simple dynamics.
After fixing the parameters of the model such as to reproduce the relation
between deconfinement temperature and zero-temperature string tension found in
lattice Yang-Mills theory, a surprisingly accurate prediction of the spatial
string tension in the deconfined phase results. Furthermore, the Pontryagin
index associated with the lattice random surfaces of the model is constructed.
This allows to also predict the topological susceptibility; the result is
compatible with measurements in lattice Yang-Mills theory. Thus, for the first
time an effective model description of the infrared sector emerges which
simultaneously and consistently reproduces both confinement and the topological
aspects of Yang-Mills theory within a unified framework. Further details can be
found in hep-lat/9912003 and hep-lat/0004013, both to appear in Nucl. Phys. B.

</DOC>
<DOC>
<DOCNO> 174510 </DOCNO>
High sensitivity double beta decay study of 116-Cd and 100-Mo with the


  The unique features (super-low background and large sensitive volume) of the
CTF and BOREXINO set ups are used in the CAMEO project for a high sensitivity
study of 100-Mo and 116-Cd neutrinoless double beta decay. Pilot measurements
with 116-Cd and Monte Carlo simulations show that the sensitivity of the CAMEO
experiment (in terms of the half-life limit for neutrinoless double beta decay)
is (3-5) 10^24 yr with a 1 kg source of 100-Mo (116-Cd, 82-Se, and 150-Nd) and
about 10^26 yr with 65 kg of enriched 116-CdWO_4 crystals placed in the liquid
scintillator of the CTF. The last value corresponds to a limit on the neutrino
mass of less than 0.06 eV. Similarly with 1000 kg of 116-CdWO_4 crystals
located in the BOREXINO apparatus the neutrino mass limit can be pushed down to
m_nu<0.02 eV.

</DOC>
<DOC>
<DOCNO> 10368 </DOCNO>
Non-Newtonian Poiseuille flow of a gas in a pipe


  The Bhatnagar-Gross-Krook kinetic model of the Boltzmann equation is solved
for the steady cylindrical Poiseuille flow fed by a constant gravity field. The
solution is obtained as a perturbation expansion in powers of the field
(through fourth order) and for a general class of repulsive potentials. The
results, which are hardly sensitive to the interaction potential, suggest that
the expansion is only asymptotic. A critical comparison with the profiles
predicted by the Navier-Stokes equations shows that the latter fail over
distances comparable to the mean free path. In particular, while the
Navier-Stokes description predicts a monotonically decreasing temperature as
one moves apart from the cylinder axis, the kinetic theory description shows
that the temperature has a local minimum at the axis and reaches a maximum
value at a distance of the order of the mean free path. Within that distance,
the radial heat flows from the colder to the hotter points, in contrast to what
is expected from the Fourier law. Furthermore, a longitudinal component of the
heat flux exists in the absence of gradients along the longitudinal direction.
Non-Newtonian effects, such as a non uniform hydrostatic pressure and normal
stress differences, are also present.

</DOC>
<DOC>
<DOCNO> 68604 </DOCNO>
Multibaryons in the collective coordinate approach to the SU(3) Skyrme


  We obtain the rotational spectrum of strange multibaryon states by performing
the SU(3) collective coordinate quantization of the static multi-Skyrmions.
These background configurations are given in terms of rational maps, which are
very good approximations and share the same symmetries as the exact solutions.
Thus, the allowed quantum numbers in the spectra and the structure of the
collective Hamiltonians we obtain are also valid in the exact case. We find
that the predicted spectra are in overall agreement with those corresponding to
the alternative bound state soliton model.

</DOC>
<DOC>
<DOCNO> 9975 </DOCNO>
Ordering of dipolar Ising crystals


  We study Ising systems of spins with dipolar interactions. We find a simple
approximate relation for the interaction energy between pairs of parallel
lattice columns of spins running along the Ising spin direction. This relation
provides insight into the relation between lattice geometry and the nature of
the ordered state. It can be used to calculate ground state energies. We have
also obtained ground state energies and ordering temperatures T_0 from Monte
Carlo simulations. Simple empirical relations, that give T_0 for simple and
body centered tetragonal lattices in terms of lattice parameters are also
established. Finally, the nature of the ordered state and T_0 are determined
for Fe_8 clusters, which crystallize on a triclinic lattice.

</DOC>
<DOC>
<DOCNO> 12627 </DOCNO>
Energetic Components of Cooperative Protein Folding


  A new lattice protein model with a four-helix bundle ground state is analyzed
by a parameter-space Monte Carlo histogram technique to evaluate the effects of
an extensive variety of model potentials on folding thermodynamics. Cooperative
helical formation and contact energies based on a 5-letter alphabet are found
to be insufficient to satisfy calorimetric and other experimental criteria for
two-state folding. Such proteinlike behaviors are predicted, however, by models
with polypeptide-like local conformational restrictions and
environment-dependent hydrogen bonding-like interactions.

</DOC>
<DOC>
<DOCNO> 121396 </DOCNO>
Models for Accretion Disk Fluctuations through Self-Organized


  The possibility that some of the observed X-ray and optical variability in
active galactic nuclei and galactic black hole candidates is produced in
accretion disks through the development of a self-organized critical state is
reconsidered. New simulations, including more complete calculations of
relativistic effects, do show that this model can produce light-curves and
power-spectra for the variability which agree with the range observed in
optical and X-ray studies of AGN and X-ray binaries. However, the universality
of complete self-organized criticality is not quite achieved. This is mainly
because the character of the variations depend quite substantially on the
extent of the unstable disk region. If it extends close to the innermost stable
orbit then a physical scale is introduced and the scale-free character of
self-organized criticality is vitiated. Significant dependence of the power
spectrum density slope on the type of diffusion within the disk and a weaker
dependence on the amount of differential rotation are noted. When general
relativistic effects are incorporated in the models, additional substantial
differences are produced if the disk is viewed from directions far from the
accretion disk axis.

</DOC>
<DOC>
<DOCNO> 151244 </DOCNO>
Recovery of Dirac Equations from Their Solutions


  We deal with quantum field theory in the restriction to external Bose fields.
Let $(i\gamma^\mu\partial_\mu - \mathcal{B})\psi=0$ be the Dirac equation. We
prove that a non-quantized Bose field $\mathcal{B}$ is a functional of the
Dirac field $\psi$, whenever this $\psi$ is strictly canonical. Performing the
trivial verification for the $\mathcal{B} := m = $ constant which yields the
free Dirac field, we also prepare the tedious verifications for all
$\mathcal{B}$ which are non-quantized and static. Such verifications must not
be confused, however, with the easy and rigorous proof of our formula, which is
shown in detail.

</DOC>
<DOC>
<DOCNO> 101255 </DOCNO>
Spectral involutions on rational elliptic surfaces


  In this paper we describe a four dimensional family of special rational
elliptic surfaces admitting an involution with isolated fixed points. For each
surface in this family we calculate explicitly the action of a spectral version
of the involution (namely of its Fourier-Mukai conjugate) on global line
bundles and on spectral data. The calculation is carried out both on the level
of cohomology and in the derived category. We find that the spectral involution
behaves like a fairly simple affine transformation away from the union of those
fiber components which do not intersect the zero section. These results are the
key ingredient in the construction of Standard-Model bundles in [DOPWa].

</DOC>
<DOC>
<DOCNO> 69995 </DOCNO>
Why N*'s are Important


  The study of N*'s can provide us with critical insights into the nature of
QCD in the confinement domain. The keys to progress in this domain are the
identification of its important degrees of freedom and the effective forces
between them. I report on the growing evidence in support of the flux tube
model, and comment on the connection between this model and spontaneous chiral
symmetry breaking, on the spin-dependence of the long-range confining
potential, on the evidence for short-range one gluon exchange, on instantons,
and on the one pion exchange model.

</DOC>
<DOC>
<DOCNO> 100061 </DOCNO>
Toric Quotients with Universal Curve Covering Property


  We consider subtorus actions on complex toric varieties. A natural candidate
for a categorical quotient of such an action is the so-called toric quotient, a
universal object constructed in the toric category. We prove that if the toric
quotient satisfies a universal curve covering property and if in addition the
quotient variety is of expected dimension then the toric quotient is in fact a
categorical quotient in the category of algebraic varieties.
  For example the universal curve covering property is automatically satisfied
for the toric quotient of a subtorus action on a toric variety whose fan has a
convex support. In this way we obtain a large class of examples of categorical
quotients for subtorus actions.

</DOC>
<DOC>
<DOCNO> 70286 </DOCNO>
Critical coupling for chiral symmetry breaking in QCD motivated models


  We determine the critical coupling constant above which dynamical chiral
symmetry breaking occurs in a class of QCD motivated models where the gluon
propagator has an enhanced infrared behavior. Using methods of bifurcation
theory we find that the critical value of the coupling constant is always
smaller than the one obtained for QCD.

</DOC>
<DOC>
<DOCNO> 12402 </DOCNO>
Order and Frustration in Chiral Liquid Crystals


  This paper reviews the complex ordered structures induced by chirality in
liquid crystals. In general, chirality favors a twist in the orientation of
liquid-crystal molecules. In some cases, as in the cholesteric phase, this
favored twist can be achieved without any defects. More often, the favored
twist competes with applied electric or magnetic fields or with geometric
constraints, leading to frustration. In response to this frustration, the
system develops ordered structures with periodic arrays of defects. The
simplest example of such a structure is the lattice of domains and domain walls
in a cholesteric phase under a magnetic field. More complex examples include
defect structures formed in two-dimensional films of chiral liquid crystals.
The same considerations of chirality and defects apply to three-dimensional
structures, such as the twist-grain-boundary and moire phases.

</DOC>
<DOC>
<DOCNO> 68922 </DOCNO>
Properties of Regge Trajectories


  Early Chew-Frautschi plots show that meson and baryon Regge trajectoies are
approximately linear and non-intersecting. In this paper, we reconstruct all
Regge trajectories from the most recent data. Our plots show that meson
trajectories are non-linear and intersecting. We also show that all current
meson Regge trajectories models are ruled out by data.

</DOC>
<DOC>
<DOCNO> 67816 </DOCNO>
Equilibration of the Gluon-Minijet Plasma at RHIC and LHC


  We study the production and equilibration of the gluon-minijet plasma
expected to be formed in the central region of ultrarelativistic heavy-ion
collisions at the BNL-RHIC and the CERN-LHC by solving a self-consistent
relativistic transport equation. We compute the minijet production within
perturbative QCD. Subsequent collisions among the semi-hard partons are treated
by considering the elastic gg -> gg processes with screening of the long
wavelength modes taken into account. We determine the time $\tau_{eq}$ where
close to ideal hydrodynamic flow sets in, and find rather similar numbers for
central heavy-ion collisions at BNL-RHIC and CERN-LHC energies. The number
densities, energy densities and temperatures of the minijet plasma are found to
be different at RHIC and LHC, e.g. $T(\tau_{eq})\sim220$ MeV and 380 MeV,
respectively.

</DOC>
<DOC>
<DOCNO> 72101 </DOCNO>
Gluon Radiation in Top Quark Production and Decay at $e^+e^-$ Colliders


  We study gluon radiation in top quark production above threshold at high
energy $e^+e^-$ colliders. We allow for the top quarks to be off-shell,
considering radiation in both the top production and decay processes
simultaneously. Our calculation includes all top width effects, spin
correlations, and $b$ quark mass effects. We study the effects of gluon
radiation on top mass reconstuction and examine the interference between
production- and decay-stage radiation, which can be sensitive to the value of
the top quark decay width.

</DOC>
<DOC>
<DOCNO> 119628 </DOCNO>
First results of UVES at VLT: abundancesin the Sgr dSph


  Two giants of the Sagittarius dwarf spheroidal have been observed with the
UVES spectrograph on the ESO 8.2m Kueyen telescope, during the commissioning of
the instrument. Sgr 139 has [Fe/H]=-0.28 and Sgr 143 [Fe/H]=-0.21, these values
are considerably higher than photometric estimates of the metallicity of the
main population of Sgr. We derived abundances for O, Na, Mg, Al, Si, Ca, Sc,
Ti, V, Cr, Mn, Co, Ni, Cu, Y, Ba, La, Ce, Nd and Eu; the abundance ratios found
are essentially solar with a few exceptions: Na shows a strong overdeficiency,
the heavy elements Ba to Eu, are overabundant, while Y is underabundat. The
high metallicity derived implies that the Sgr galaxy has experienced a high
level of chemical processing. The stars had been selected to be representative
of the two main stellar populations of Sagittarius, however, contrary to what
expected from the photometry, the two stars show a very similar chemical
composition. We argue that the most likely explanation for the difference in
the photometry of the two stars is a different distance, Sgr 143 being about
2Kpc nearer than Sgr 139. This result suggests that the interpretation of
colour -- magnitude diagrams of Sgr is more complex than previously thought and
the effect of the line of sight depth should not be neglected. It also shows
that spectroscopic abundances are required for a correct interpretation of Sgr
populations.

</DOC>
<DOC>
<DOCNO> 70004 </DOCNO>
Electroweak Model Independent Tests for SU(3) Symmetry in Hadronic B


  We study effects of new physics beyond the Standard Model on SU(3) symmetry
in charmless hadronic two body B decays. It is found that several equalities
for some of the decay amplitudes, such as $A(B_d (B_u) \to \pi^+\pi^-,\pi^+ K^-
(\pi^- \bar K^0)) =A(B_s \to K^+ \pi^-, K^- K^+ (K^0 \bar K^0))$, $A(B_d \to
\pi^+\rho^-, \pi^- \rho^+, K^-\rho^+, \pi^+ K^{*-}) = A(B_s \to K^+ \rho^-,
\pi^- K^{*+}, K^- K^{*+}, K^+ K^{*-})$, $A(B_d (B_u) \to \rho^+\rho^-, \rho^+
K^{*-}(\rho^- \bar K^{*0})) =A(B_s \to K^{*+} \rho^-, K^{*-} K^{*+} (K^{*0}
\bar K^{*0}))$, predicted by SU(3) symmetry in the SM are not affected by new
physics. These relations provide important electroweak model independent tests
for SU(3) symmetry in B decays.

</DOC>
<DOC>
<DOCNO> 13322 </DOCNO>
Superconductor-Insulator Quantum Phase Transitions


  In these lectures, superconductivity in impure thin films close to the
absolute zero of temperature is discussed. The behavior as function of the
applied magnetic field and the amount of impurities suggests the presence of a
superconductor-insulator transition at zero temperature. The theory of
superconductivity in the limit where all the electrons become tightly bound in
pairs is used to explain the main characteristics of the transition. In that
limit, where the theory becomes equivalent to a phase-only theory, electron
pairs exist on either side of the transition. The presentation is pedagogical
in nature and includes exercises as a learning aid for those new to the field.

</DOC>
<DOC>
<DOCNO> 68220 </DOCNO>
High Temperature Symmetry Nonrestoration


  This is a short review on the subject of symmetry nonrestoration at high
temperature. Special emphasis is put on experimental discoveries and different
theoretical mechanisms. At the end, possible cosmological applications are
briefly mentioned.

</DOC>
<DOC>
<DOCNO> 84314 </DOCNO>
Dynamic Cosmic Strings I


  The field equations for a time dependent cylindrical cosmic string coupled to
gravity are reformulated in terms of geometrical variables defined on a
2+1-dimensional spacetime by using the method of Geroch decomposition. Unlike
the 4-dimensional spacetime the reduced case is asymptotically flat. A
numerical method for solving the field equations which involves conformally
compactifying the space and including null infinity as part of the grid is
described. It is shown that the code reproduces the results of a number of
vacuum solutions with one or two degrees of freedom. In the final section the
interaction between the cosmic string and a pulse of gravitational radiation is
briefly described. This will be fully analysed in the sequel.

</DOC>
<DOC>
<DOCNO> 11027 </DOCNO>
Elastic theory of quantum Hall smectics: effects of disorder


  We study the effect of disorder on quantum Hall smectics within the framework
of an elastic theory. Based on a renormalization group calculation, we derive
detailed results for the degrees of translational and orientational order of
the stripe pattern at zero temperature and carefully map out the disorder and
length-scale regimes in which the system effectively exhibits smectic, nematic,
or isotropic behavior. We show that disorder always leads to a finite density
of free dislocations and estimate the scale on which they begin to appear.

</DOC>
<DOC>
<DOCNO> 11520 </DOCNO>
Error and attack tolerance of complex networks


  Many complex systems, such as communication networks, display a surprising
degree of robustness: while key components regularly malfunction, local
failures rarely lead to the loss of the global information-carrying ability of
the network. The stability of these complex systems is often attributed to the
redundant wiring of the functional web defined by the systems' components. In
this paper we demonstrate that error tolerance is not shared by all redundant
systems, but it is displayed only by a class of inhomogeneously wired networks,
called scale-free networks. We find that scale-free networks, describing a
number of systems, such as the World Wide Web, Internet, social networks or a
cell, display an unexpected degree of robustness, the ability of their nodes to
communicate being unaffected by even unrealistically high failure rates.
However, error tolerance comes at a high price: these networks are extremely
vulnerable to attacks, i.e. to the selection and removal of a few nodes that
play the most important role in assuring the network's connectivity.

</DOC>
<DOC>
<DOCNO> 123033 </DOCNO>
Cosmic Dust: The Ulysses perspective


  The Ulysses spacecraft, launched in October 1990, orbits the Sun on a polar
trajectory. The spacecraft is equipped with a highly sensitive impact-
ionization dust detector which can in situ measure cosmic dust grains in the
mass range 10^-9 to 10^-19 kg. With the Ulysses dust detector dust streams
originating from Jupiter's volcanically active moon Io have been discovered as
well as interstellar dust particles sweeping through the solar system. The
distribution of interplanetary dust grains has been measured at high ecliptic
latitudes with Ulysses for the first time. The Ulysses measurements of
interplanetary dust, dust grains interacting electromagnetically with the
magnetosphere of Jupiter and measurements of interstellar dust in the solar
system are reviewed.

</DOC>
<DOC>
<DOCNO> 85081 </DOCNO>
Microlocal spectrum condition and Hadamard form for vector-valued


  Some years ago, Radzikowski has found a characterization of Hadamard states
for scalar quantum fields on a four-dimensional globally hyperbolic spacetime
in terms of a specific form of the wavefront set of their two-point functions
(termed `wavefront set spectrum condition'), thereby initiating a major
progress in the understanding of Hadamard states and the further development of
quantum field theory in curved spacetime. In the present work, we extend this
important result on the equivalence of the wavefront set spectrum condition
with the Hadamard condition from scalar fields to vector fields (sections in a
vector bundle) which are subject to a wave-equation and are quantized so as to
fulfill the covariant canonical commutation relations, or which obey a Dirac
equation and are quantized according to the covariant anti-commutation
relations, in any globally hyperbolic spacetime having dimension three or
higher. In proving this result, a gap which is present in the published proof
for the scalar field case will be removed. Moreover we determine the
short-distance scaling limits of Hadamard states for vector-bundle valued
fields, finding them to coincide with the corresponding flat-space, massless
vacuum states.

</DOC>
<DOC>
<DOCNO> 10931 </DOCNO>
Morphology of Ion-Sputtered Surfaces


  We derive a stochastic nonlinear continuum theory to describe the
morphological evolution of amorphous surfaces eroded by ion bombardment.
Starting from Sigmund's theory of sputter erosion, we calculate the
coefficients appearing in the continuum equation in terms of the physical
parameters characterizing the sputtering process. We analyze the morphological
features predicted by the continuum theory, comparing them with the
experimentally reported morphologies. We show that for short time scales, where
the effect of nonlinear terms is negligible, the continuum theory predicts
ripple formation. We demonstrate that in addition to relaxation by thermal
surface diffusion, the sputtering process can also contribute to the smoothing
mechanisms shaping the surface morphology. We explicitly calculate an effective
surface diffusion constant characterizing this smoothing effect, and show that
it is responsible for the low temperature ripple formation observed in various
experiments. At long time scales the nonlinear terms dominate the evolution of
the surface morphology. The nonlinear terms lead to the stabilization of the
ripple wavelength and we show that, depending on the experimental parameters
such as angle of incidence and ion energy, different morphologies can be
observed: asymptotically, sputter eroded surfaces could undergo kinetic
roughening, or can display novel ordered structures with rotated ripples.
Finally, we discuss in detail the existing experimental support for the
proposed theory, and uncover novel features of the surface morphology and
evolution, that could be directly tested experimentally.

</DOC>
<DOC>
<DOCNO> 174541 </DOCNO>
Overview of the Status and Strangeness Capabilities of STAR


  STAR is a large acceptance spectrometer capable of precision measurements of
a wide variety of strange particles. We discuss the STAR detector, its
configuration during the first two years of RHIC operation, and its initial
performance for Au+Au collisions. The expected performance for strangeness
physics and initial data on strange particle reconstruction in Au+Au collisions
are presented.

</DOC>
<DOC>
<DOCNO> 71834 </DOCNO>
Confinement in three dimensional magnetic monopole--dipole gas


  Confinement of electrically charged test particles in the dilute plasma of
monopoles and pointlike magnetic dipoles is studied. We calculate the tension
of the string emerging between the infinitely separated test particles. The
string tension is an increasing function of the dipole density provided other
parameters of the plasma are fixed. The relevance of our results to confining
gauge theories is discussed.

</DOC>
<DOC>
<DOCNO> 83244 </DOCNO>
Orthogonal Least Squares Algorithm for the Approximation of a Map and


  Radial Basis Function Networks (RBFNs) are used primarily to solve
curve-fitting problems and for non-linear system modeling. Several algorithms
are known for the approximation of a non-linear curve from a sparse data set by
means of RBFNs. However, there are no procedures that permit to define
constrains on the derivatives of the curve. In this paper, the Orthogonal Least
Squares algorithm for the identification of RBFNs is modified to provide the
approximation of a non-linear 1-in 1-out map along with its derivatives, given
a set of training data. The interest on the derivatives of non-linear functions
concerns many identification and control tasks where the study of system
stability and robustness is addressed. The effectiveness of the proposed
algorithm is demonstrated by a study on the stability of a single loop feedback
system.

</DOC>
<DOC>
<DOCNO> 11821 </DOCNO>
Impurity induced resonant state in a pseudogap state of a high


  We predict a resonance impurity state generated by the substitution of one Cu
atom with a nonmagnetic atom, such as Zn, in the pseudogap state of a high-T_c
superconductor. The precise microscopic origin of the pseudogap is not
important for this state to be formed, in particular this resonance will be
present even in the absence of superconducting fluctuations in the normal
state. In the presence of superconducting fluctuations, we predict the
existence of a counterpart impurity peak on a symmetric bias.
 The nature of impurity resonance is similar to the previously studied
resonance in the d-wave superconducting state.

</DOC>
<DOC>
<DOCNO> 83470 </DOCNO>
Retrieval from Captioned Image Databases Using Natural Language


  It might appear that natural language processing should improve the accuracy
of information retrieval systems, by making available a more detailed analysis
of queries and documents. Although past results appear to show that this is not
so, if the focus is shifted to short phrases rather than full documents, the
situation becomes somewhat different. The ANVIL system uses a natural language
technique to obtain high accuracy retrieval of images which have been annotated
with a descriptive textual caption. The natural language techniques also allow
additional contextual information to be derived from the relation between the
query and the caption, which can help users to understand the overall
collection of retrieval results. The techniques have been successfully used in
a information retrieval system which forms both a testbed for research and the
basis of a commercial system.

</DOC>
<DOC>
<DOCNO> 11381 </DOCNO>
Cationic ordering control of magnetization in Sr2FeMoO6 double


  The role of the synthesis conditions on the cationic Fe/Mo ordering in
Sr2FeMoO6 double perovskite is addressed. It is shown that this ordering can be
controlled and varied systematically. The Fe/Mo ordering has a profound impact
on the saturation magnetization of the material. Using the appropriate
synthesis protocol a record value of 3.7muB/f.u. has been obtained. Mossbauer
analysis reveals the existence of two distinguishable Fe sites in agreement
with the P4/mmm symmetry and a charge density at the Fe(m+) ions significantly
larger than (+3) suggesting a Fe contribution to the spin-down conduction band.
The implications of these findings for the synthesis of Sr2FeMoO6 having
optimal magnetoresistance response are discussed.

</DOC>
<DOC>
<DOCNO> 151179 </DOCNO>
AdS/CFT Dualities and the Unitary Representations of Non-compact Groups


  I review the relationship between AdS/CFT (anti-de Sitter / conformal field
theory) dualities and the general theory of positive energy unitary
representations of non-compact space-time groups and supergroups. I show, in
particular, how one can go from the manifestly unitary compact basis of the
lowest weight (positive energy) representations of the conformal group (Wigner
picture) to the manifestly covariant coherent state basis (Dirac picture). The
coherent states labelled by the space-time coordinates correspond to covariant
fields with a definite conformal dimension. These results extend to higher
dimensional Minkowskian spacetimes as well as generalized spacetimes defined by
Jordan algebras and Jordan triple systems. The second part of my talk discusses
the extension of the above results to conformal supergroups of Minkowskian
superspaces as well as of generalized superspaces defined by Jordan
superalgebras. The (super)-oscillator construction of generalized
(super)-conformal groups can be given a dynamical realization in terms of
generalized (super)-twistor fields.

</DOC>
<DOC>
<DOCNO> 151814 </DOCNO>
Yukawa Textures And Horava-Witten M-Theory


  The general structure of the matter Kahler metric in the $\kappa^{2/3}$
expansion of Horava-Witten M-theory with nonstandard embeddings is examined. It
is shown that phenomenological models based on this structure can lead to
Yukawa and V$_{\rm CKM}$ hierarchies (consistent with all data) without
introducing ad hoc small parameters if the 5-branes lie near the distant
orbifold plane and the instanton charges of the physical plane vanish. M-theory
thus offers an alternate way of describing these hierarchies, different from
the conventional models of Yukawa textures.

</DOC>
<DOC>
<DOCNO> 84720 </DOCNO>
Non-differentiable Degrees of Freedom : Fluctuating Metric Signature


  In this article we investigate the metric signature as a non-differentiable
({\it i.e.} discrete as opposed to continuous) degree of freedom. The specific
model is a vacuum 7D Universe on the principal bundle with an SU(2) structural
group. An analytical solution is found which to a 4D observer appears as a flat
Universe with a fluctuating metric signature, and frozen extra dimensions with
an SU(2) instanton gauge field. A piece of this solution with linear size of
the Planck length ($\approx l_{Pl}$) can be considered as seeding the quantum
birth of a regular Universe. A boundary of this piece can initiate the
formation of a Lorentzian Universe filled with the gauge fields and in which
the extra dimensions have been ``frozen''.

</DOC>
<DOC>
<DOCNO> 121425 </DOCNO>
Numerous Old Starburst Galaxies in the Local Universe


  Old starburst galaxies are deficient in O stars, and hence do not exhibit
strong line emission in the optical regime. However, there remain many B stars,
which are expected to heat dust grains and generate strong continuum emission
in the far-infrared. The IRAS data for a statistically complete sample of
nearby galaxies reveal for the first time that such objects are as numerous as
30-40% of the local galaxy population.

</DOC>
<DOC>
<DOCNO> 67885 </DOCNO>
Predictions for Z --> mu tau and Related Reactions


  We discuss predictions for the lepton-flavour changing decays Z --> e mu, mu
tau, e tau which may be searched for at the Giga-Z option of the Tesla Linear
Collider project with Z resonance production rates as high as 10^9. We try to
be as model-independent as possible and consider both the Dirac and Majorana
mass cases. The Standard Model, if being minimally extended by the inclusion of
light neutrino masses with some mixings as observed in neutrino oscillation
search experiments, predicts completely negligible rates. With a more general
neutrino content quite interesting expectations may be derived.

</DOC>
<DOC>
<DOCNO> 119155 </DOCNO>
Magnetohydrodynamic Instabilities in Shearing, Rotating, Stratified


  We investigate shear and buoyancy instabilities in radially stratified,
magnetized, cylindrical flows, for application to magnetocentrifugally driven
winds and to magnetized accretion disks. We identify and study nine principal
types of instabilities/overstabilities. When magnetic fields are predominantly
toroidal, as in protostellar winds, the system exhibits axisymmetric
fundamental (FM) and toroidal resonance modes, axisymmetric and
non-axisymmetric toroidal buoyancy (TB) modes, and non-axisymmetric
magnetorotational instability (MRI) modes. Winds with sufficiently steep field
gradients are unstable to the FM, which promotes narrow dense jets in the
centers of wider winds. The TB modes promote small-scale radial mixing. The
MRIs have very low growth rates under low-temperature wind conditions. The
stabilization of buoyancy modes by shear, and of MRIs by compressibility, may
be important in allowing protostellar winds to propagate over vast distances in
space. When magnetic fields are predominantly poloidal, as in winds close to
their source or in astrophysical disks, the system exhibits axisymmetric
Balbus-Hawley (BH), poloidal buoyancy (PB), non-axisymmetric geometric buoyancy
(GPB), and poloidal resonance modes. The BH mode has the fastest growth rate.
The PB mode promotes radial mixing on small scales. The GPB mode at high m is
readily stabilized by shear. We extend previous MRI analyses to focus on
compressibility. We introduce a ``coherent wavelet'' technique to derive
closed-form expressions for instantaneous instability criteria, growth rates,
and net amplification factors for non-axisymmetric MRIs in compressible flows
with both poloidal and toroidal fields. We confirm that these are in excellent
agreement with the results of shearing-sheet temporal integrations.

</DOC>
<DOC>
<DOCNO> 70698 </DOCNO>
Quantization of eletric charge, the neutrino and generation


  text of abstract It is showed that the eletric charge quantization is
unconnected to Majorana neutrino in the non-universal generations
leptoquark-bilepton flavordynamics which includes the right-handed neutrino and
an explicit U(1) factor in the gauge semisimple group.

</DOC>
<DOC>
<DOCNO> 101647 </DOCNO>
Polar Homology


  For complex projective manifolds we introduce polar homology groups, which
are holomorphic analogues of the homology groups in topology. The polar
k-chains are subvarieties of complex dimension k with meromorphic forms on
them, while the boundary operator is defined by taking the polar divisor and
the Poincare residue on it.

</DOC>
<DOC>
<DOCNO> 120392 </DOCNO>
GRB990712: First Indication of Polarization Variability in a Gamma-ray


  We report the detection of significant polarization in the optical afterglow
of GRB990712 on three instances 0.44, 0.70 and 1.45 days after the gamma-ray
burst, with (P, theta) being (2.9% +- 0.4%, 121.1 degr +- 3.5 degr), (1.2% +-
0.4%, 116.2 degr +- 10.1 degr) and (2.2% +- 0.7%, 139.2 degr +- 10.4 degr)
respectively. The polarization is intrinsic to the afterglow. The degree of
polarization is not constant, and smallest at the second measurement. The
polarization angle does not vary significantly during these observations. We
find that none of the existing models predict such polarization variations at
constant polarization angle, and suggest ways in which these models might be
modified to accommodate the observed behavior of this afterglow.

</DOC>
<DOC>
<DOCNO> 68705 </DOCNO>
Mixing and CP violation with Quasidegenerate Majorana Neutrinos


  We study the exactly degenerate case for three lefthanded Majorana neutrinos
building a general parametrization for the leptonic mixing matrix characterized
by two angles and one CP violating phase and identify a weak-basis invariant
relevant, in this case, for CP violation. After lifting the degeneracy, this
parametrization accommodates the present data on atmospheric and solar
neutrinos, as well as neutrinoless double beta decay. Some of the leptonic
mixing ans\"atze suggested in the literature correspond to special cases of
this parametrization.

</DOC>
<DOC>
<DOCNO> 122730 </DOCNO>
The SBF Survey of Galaxy Distances. IV. SBF Magnitudes, Colors, and


  We report data for $I$ band Surface Brightness Fluctuation (SBF) magnitudes,
V-I colors, and distance moduli for 300 galaxies. The Survey contains E, S0 and
early-type spiral galaxies in the proportions of 49:42:9, and is essentially
complete for E galaxies to Hubble velocities of 2000 km/s, with a substantial
sampling of E galaxies out to 4000 km/s. The median error in distance modulus
is 0.22 mag.
  We also present two new results from the Survey. (1) We compare the mean
peculiar flow velocity (bulk flow) implied by our distances with predictions of
typical cold dark matter transfer functions as a function of scale, and find
very good agreement with cold, dark matter cosmologies if the transfer function
scale parameter $\Gamma$, and the power spectrum normalization $\sigma_8$ are
related by $\sigma_8 \Gamma^{-0.5} \approx 2\pm0.5$. Derived directly from
velocities, this result is independent of the distribution of galaxies or
models for biasing. The modest bulk flow contradicts reports of large-scale,
large-amplitude flows in the $\sim200$ Mpc diameter volume surrounding our
Survey volume. (2) We present a distance-independent measure of absolute galaxy
luminosity, \Nbar, and show how it correlates with galaxy properties such as
color and velocity dispersion, demonstrating its utility for measuring galaxy
distances through large and unknown extinction.

</DOC>
<DOC>
<DOCNO> 68605 </DOCNO>
Effective potential calculation of the MSSM lightest CP-even Higgs boson


  I summarize results of two-loop effective potential calculations of the
lightest CP-even Higgs boson mass in the minimal supersymmetric standard model.

</DOC>
<DOC>
<DOCNO> 120082 </DOCNO>
Dependence of Halo Properties on Interaction History, Environment and


  I present results from numerical N-body simulations regarding the effect of
merging events on the angular momentum distribution of galactic halos as well
as a comparison of halo growth in Press-Schechter vs. N-body methods. A total
of six simulations are used spanning 3 cosmologies: a standard flat Omega_0=1
model, an open Omega_0=0.3 model and a "tilted" flat Omega_0=1 model with
spectral index n=0.8. In each model, one run was conducted using a spatially
uniform grid of particles and one using a refined grid in a large void. In all
three models and all environments tested, the mean angular momentum of merger
remnants (halo interaction products with mass ratios 3:1 or less) is greater
than non-merger remnants. Furthermore, the dispersion in the merger-remnant
angular momentum distribution is smaller than the dispersion of the non-merger
distribution. The interpretation most consistent with the data is that the
orbital angular momentum of the interactors is important in establishing the
final angular momentum of the merger product. I give the angular momentum
distribution which describes the merger remnant population.
  I trace the most massive progenitor of L_* galactic-mass halos (uniform grid)
and 10^{11} solar mass halos (refined void) from redshift z=0 back to z=5.
Monte-Carlo mass histories match simulations reasonably well for the latter
sample. I find that for halos of mass 10^{12} to 10^{14} solar masses, this
method can underestimate the mass of progenitors by 20%, hence yielding
improper formation redshifts of halos. With this caveat, however, the general
shapes of halo mass histories and formation-time distributions are preserved.

</DOC>
<DOC>
<DOCNO> 118103 </DOCNO>
Understanding NLR in Seyfert Galaxies: numerical simulation of jet-cloud


  Recent HST observations suggest that the NLR in Seyfert Galaxies can be the
result of interaction between jet and external inhomogeneous medium; following
this suggestion we perform numerical simulations considering the impact of a
radiative jet on a dense cloud. We approach the problem adopting a
hydrodynamical code, that consents us to study in detail the jet hydrodynamics,
while we choose a more simplified treatment of radiative processes, in order to
give a qualitatively good interpretation of the emission processes. Our three
main purposes are: i) to reproduce in our simulations the physical conditions
observed in the NLR of Seyfert Galaxies, ii) to obtain physical constraints of
the jet parameters and iii) to study the jet capability to photoionize the
surrounding medium.

</DOC>
<DOC>
<DOCNO> 40583 </DOCNO>
On "Sub-Threshold" Reactions Involving Nuclear Fission


  We analyze reactions of several types that are naively below threshold but
can proceed because of the release of binding energy from nuclear fission and
occasionally the formation of Coulombic bound states. These reactions include
(i) photofission with pion production and (ii) charged current neutrino-nucleus
reactions that lead to fission and/or formation of a Coulomb bound state of a
$\mu^-$ with the nucleus of a fission fragment. We comment on the possible
experimental observation of these reactions.

</DOC>
<DOC>
<DOCNO> 69364 </DOCNO>
Top-quark couplings to TeV resonances at future lepton colliders


  We study the processes $W_L W_L \to t \bar t$ and $W_L Z_L \to t\bar b (\bar
t b)$ at future lepton colliders as probes of the couplings of the top quark to
resonances at the TeV scale. We consider the cases in which the dominant low
energy feature of a strongly interacting electroweak symmetry breaking sector
is either a scalar or a vector resonance with mass near 1 TeV. We find that
future lepton colliders with high energy and high luminosity have great
potential to sensitively probe these physics scenarios. In particular, at a 1.5
TeV linear collider with an integrated luminosity of 200 fb$^{-1}$, we expect
about 120 events for either a scalar or a vector to decay to $t\bar t, t \bar
b$. Their leading partial decay widths, which characterize the coupling
strengths, can be statistically determined to about 10% level.

</DOC>
<DOC>
<DOCNO> 67835 </DOCNO>
Gauge Interactions in the Dual Standard Model


  We present a geometric argument for the transformation properties of SU(5)
--> S(U(3) x U(2)) monopoles under the residual gauge symmetry. This strongly
supports the proposal that monopoles of the dual standard model interact via a
gauge theory of the standard model symmetry group, with the monopoles having
the same spectrum as the standard model fermions.

</DOC>
<DOC>
<DOCNO> 102170 </DOCNO>
Random Delaunay triangulations and metric uniformization


  In this paper a new connection between the discrete conformal geometry
problem of disk pattern construction and the continuous conformal geometry
problem of metric uniformization is presented. In a nutshell, we discuss how to
construct disk patterns by optimizing an objective function, which turns out to
be intimately related to hyperbolic volume. With the use of random Delaunay
triangulations we then average this objective function to construct an
objective function on the metrics conformal to a fixed one. Finally using this
averaged objective function we may reprove the uniformization theorem in two
dimensions.

</DOC>
<DOC>
<DOCNO> 151328 </DOCNO>
Multi-instantons in R^4 and Minimal Surfaces in R^{2,1}


  It is known that self-duality equations for multi-instantons on a line in
four dimensions are equivalent to minimal surface equations in three
dimensional Minkowski space. We extend this equivalence beyond the equations of
motion and show that topological number, instanton moduli space and
anti-self-dual solutions have representations in terms of minimal surfaces. The
issue of topological charge is quite subtle because the surfaces that appear
are non-compact. This minimal surface/instanton correspondence allows us to
define a metric on the configuration space of the gauge fields. We obtain the
minimal surface representation of an instanton with arbitrary charge. The
trivial vacuum and the BPST instanton as minimal surfaces are worked out in
detail. BPS monopoles and the geodesics are also discussed.

</DOC>
<DOC>
<DOCNO> 83082 </DOCNO>
Requirements of Text Processing Lexicons


  As text processing systems expand in scope, they will require ever larger
lexicons along with a parsing capability for discriminating among many senses
of a word. Existing systems do not incorporate such subtleties in meaning for
their lexicons. Ordinary dictionaries contain such information, but are largely
untapped. When the contents of dictionaries are scrutinized, they reveal many
requirements that must be satisfied in representing meaning and in developing
semantic parsers. These requirements were identified in research designed to
find primitive verb concepts. The requirements are outlined and general
procedures for satisfying them through the use of ordinary dictionaries are
described, illustrated by building frames for and examining the definitions of
"change" and its uses as a hypernym in other definitions.

</DOC>
<DOC>
<DOCNO> 67774 </DOCNO>
Effective cross section and spatial structure of the hadrons


  Informations about the spatial structure of parton distribution within the
hadron are provided by the ratios between the inclusive cross sections for a
pair of jets, two pairs of jets, three pairs of jets..., and so on. It results,
however that these ratios depend not only on the spatial distribution but also,
and even more, on the multiplicity distribution of the initial partons.

</DOC>
<DOC>
<DOCNO> 151851 </DOCNO>
A Note on Non-Commutative Field Theory and Stability of Brane-Antibrane


  It has been conjectured that a pair of D5 - anti D5 branes wrapped on some
non-trivial two cycle of a Calabi-Yau manifold becomes a stable BPS D3 brane in
the presence of a very large B field and magnetic fluxes on their worldvolumes.
We discuss this by considering the non-commutative field theory on the
worldvolume of the pair of branes whose field multiplication is made with
respect to two different * products due to the presence of different F fields
on the two branes. The tachyonic field becomes massless for a specific choice
of the magnetic fluxes and it allows a trivial solution. Our discussion
generalizes recent results concerning stability of brane-antibrane systems on
Calabi-Yau spaces to the case of non-commutative branes.

</DOC>
<DOC>
<DOCNO> 9036 </DOCNO>
Comment on "Anomalous Spreading of Power-Law Quantum Wave Packets"


  A family of wave packets with power law tails are employed to analyze the
long time dependence of the corresponding probability density. The densities,
associated to packets for free particles in the one-dimensional space, with
sufficiently long tails decay asymptotically in time following a $t^{-\beta}$
law (with $\beta<1$), slower than the usual $t^{-1}$ one, including the
particular case $(ln t)^2/t$ not correctly discussed in F. Lillo and R. N.
Mantegna (Phys. Rev. Lett. 84, 1061 (2000)).

</DOC>
<DOC>
<DOCNO> 84392 </DOCNO>
Kaluza-Klein Formalism of General Spacetimes


  I describe the Kaluza-Klein approach to general relativity of 4-dimensional
spacetimes. This approach is based on the (2,2)-fibration of a generic
4-dimensional spacetime, which is viewed as a local product of a
(1+1)-dimensional base manifold and a 2-dimensional fibre space. It is shown
that the metric coefficients can be decomposed into sets of fields, which
transform as a tensor field, gauge fields, and scalar fields with respect to
the infinite dimensional group of the diffeomorphisms of the 2-dimensional
fibre space. I discuss a few applications of this formalism.

</DOC>
<DOC>
<DOCNO> 120548 </DOCNO>
The Nature of the Hard X-ray Background Sources: Optical, Near-infrared,


  With recent Chandra observations, at least 60% of the 2-10 keV background is
now resolved into discrete sources. Here we present deep optical, NIR, submm,
and 20 cm (radio) images, as well as high-quality optical spectra, of a
complete sample of 20 hard X-ray sources in a deep Chandra observation of the
SSA13 field. The thirteen I<23.5 galaxies have redshifts in the range 0.1 to
2.6. Two are quasars, five show AGN signatures, and six are z<1.5 luminous
bulge-dominated galaxies whose spectra show no obvious optical AGN signatures.
The seven spectroscopically unidentified sources have colors that are
consistent with evolved early galaxies at z=1.5-3. Only one hard X-ray source
is significantly detected in an ultradeep submm map; its millimetric redshift
is in the range z=1.2-2.4. None of the remaining 19 sources is detected in the
submm. These results probably reflect the fact that the 850-micron flux limits
obtainable with SCUBA are quite close to the expected fluxes from obscured AGN.
The hard X-ray sources have an average L(FIR)/L(2-10 keV)~60, similar to that
of local obscured AGN. The same ratio for a sample of submm selected sources is
in excess of 1100, suggesting that their FIR light is primarily produced by
star formation. Our data show that luminous hard X-ray sources are common in
bulge-dominated optically luminous galaxies. We use our measured bolometric
corrections with the 2-10 keV EBL to infer the growth of supermassive black
holes. Even with a high radiative efficiency of accretion (e=0.1), the black
hole mass density required to account for the observed light is comparable to
the local black hole mass density. (Abridged)

</DOC>
<DOC>
<DOCNO> 151105 </DOCNO>
Supergravity Instantons and the Universal Hypermultiplet


  The effective action of N=2 supersymmetric 5-dimensional supergravity arising
from compactifications of M-theory on Calabi-Yau threefolds receives
non-perturbative corrections from wrapped Euclidean membranes and fivebranes.
These contributions can be interpreted as instanton corrections in the 5
dimensional field theory. Focusing on the universal hypermultiplet, a solution
of this type is presented and the instanton action is calculated, generalizing
previous results involving membrane instantons. The instanton action is not a
sum of membrane and fivebrane contributions: it has the form reminiscent of
non-threshold bound states.

</DOC>
<DOC>
<DOCNO> 121667 </DOCNO>
Chemical abundances in cool metal rich disk dwarf stars


  The present study of spectra of twelve metal-rich cool dwarf stars, carefully
selected in order to cover a range of temperatures (~4400 - 6000 K), is a
follow up on Feltzing & Gustafsson (1998, A&AS 129, 237) with the aim to
understand the apparent over-ionization and anomalous elemental abundances
found by them for the K dwarf stars in their sample. Our method of analysis
employs synthetic spectra of the full spectrum both to constrain the continuum
level and to derive abundances. It is shown that by using this method and
imposing a strict excitation equilibrium (possible to do because of the care in
selection of observed Fe I lines) we are able to show that metal-rich K dwarf
stars do not show anomalous stellar abundances, as indicated in Feltzing &
Gustafsson (1998), and can, with reasonable efforts, be analyzed in order to
increase the number of metal-rich stars with useful chemical abundances. With
abundance analysis by means of spectrum synthesis and assuming Local
Thermodynamic Equilibrium (LTE) the abundances of Na, Si, Ca, Sc, Ti, V, Cr,
Fe, Co, Ni, and Nd have been derived. Also ionization balance is satisfied for
Fe and Cr after correcting the stellar effective temperatures such that both
ionization and excitation equilibrium were satisfied. In addition, spectra from
five cool dwarf stars of the Feltzing & Gustafsson (1998) sample have been
analyzed with the methods used in this work. They show essentially the same
abundance patterns as the new stars in this sample.

</DOC>
<DOC>
<DOCNO> 8542 </DOCNO>
Scanned Probe Microscopy of Electronic Transport in Carbon Nanotubes


  We use electrostatic force microscopy and scanned gate microscopy to probe
the conducting properties of carbon nanotubes at room temperature. Multi-walled
carbon nanotubes are shown to be diffusive conductors, while metallic
single-walled carbon nanotubes are ballistic conductors over micron lengths.
Semiconducting single-walled carbon nanotubes are shown to have a series of
large barriers to conduction along their length. These measurements are also
used to probe the contact resistance and locate breaks in carbon nanotube
circuits.

</DOC>
<DOC>
<DOCNO> 101792 </DOCNO>
Sur l'anneau de cohomologie du sch\'ema de Hilbert de $\CC^2$


  We express the product of the cohomology ring of the Hilbert scheme in terms
of the center of the algebra of the symmetric group. We give a conjecture for
the case of crepant resolutions of symplectic quotient singularities.

</DOC>
<DOC>
<DOCNO> 99292 </DOCNO>
$A_{\infty}$-structures on an elliptic curve


  The main result of this paper is the proof of the "transversal part" of the
homological mirror symmetry conjecture for an elliptic curve which states an
equivalence of two $A_{\infty}$-structures on the category of vector bundles on
an elliptic curves. The proof is based on the study of $A_{\infty}$-structures
on the category of line bundles over an elliptic curve satisfying some natural
restrictions (in particular, $m_1$ should be zero, $m_2$ should coincide with
the usual composition). The key observation is that such a structure is
uniquely determined up to homotopy by certain triple products.

</DOC>
<DOC>
<DOCNO> 84456 </DOCNO>
Fate of Kaluza-Klein Bubble


  We numerically study classical time evolutions of Kaluza-Klein bubble
space-time which has negative energy after a decay of vacuum. As the zero
energy Witten's bubble space-time, where the bubble expands infinitely, the
subsequent evolutions of Brill and Horowitz's momentarily static initial data
show that the bubble will expand in terms of the area. At first glance, this
result may support Corley and Jacobson's conjecture that the bubble will expand
forever as well as the Witten's bubble. The irregular signatures, however, can
be seen in the behavior of the lapse function in the maximal slicing gauge and
the divergence of the Kretchman invariant. Since there is no appearance of the
apparent horizon, we suspect an appearance of a naked singularity as the final
fate of this space-time.

</DOC>
<DOC>
<DOCNO> 71840 </DOCNO>
Semileptonic Form-factors from B-> K* gamma Decays in the Large Energy


  Making use of the measurement of the $B\to K^*\gamma$ branching ratio
together with the relations following from the limit of high recoil energy, we
obtain stringent constraints on the values of the form-factors entering in
heavy-to-light $B\to V\ell\ell'$ processes such as $B\to K^*\ell^+\ell^-$,
$B\to K^*\nu \bar{\nu}$ and $B\to \rho\ell\nu$ decays. We show that the
symmetry predictions, when combined with the experimental information on
radiative decays, specify a severely restricted set of values for the vector
and axial-vector form-factors evaluated at zero momentum transfer, $q^2=0$.
These constraints can be used to test model calculations and to improve our
understanding of the $q^2$-dependence of semileptonic form-factors. We stress
that the constraints remain stringent even when corrections are taken into
account.

</DOC>
<DOC>
<DOCNO> 122533 </DOCNO>
1.65mic (H-band) surface photometry of galaxies. VI: The history of star


  We have collected a large body of NIR (H band), UV (2000 A) and Halpha
measurements of late-type galaxies. These are used, jointly with spectral
evolutionary synthesis models, to study the initial mass function (IMF) in the
mass range m > 2 Mo. For spirals (Sa-Sd), Magellanic irregulars (Im) and blue
compact dwarfs (BCD), our determination is consistent with a Salpeter IMF with
an upper mass cutoff M_up = 80 Mo. The history of star formation and the amount
of total gas (per unit mass) of galaxies are found to depend primarily on their
total masses (as traced by the H band luminosities) and only secondarily on
morphological type. The present star formation activity of massive spirals is
up to 100 times smaller than that average over their lifetime, while in low
mass galaxies it is comparable to or higher than that at earlier epochs. Dwarf
galaxies have presently larger gas reservoirs per unit mass than massive
spirals. The efficiency in transforming gas into stars and the time scale for
gas depletion (10 Gyrs) are independent of the luminosity and/or of the
morphological type. These evidences are consistent with the idea that galaxies
are coeval systems,that they evolved as closed-boxes forming stars following a
simple, universal star formation law whose characteristic time scale is small
(1 Gyr) in massive spirals and large (10 Gyr) in low mass galaxies. A similar
conclusion was drawn by Gavazzi and Scodeggio (1996) to explain the
colour-magnitude relation of late-type galaxies. The consequences of this
interpretation on the evolution of the star formation rate and of the gas
density per comoving volume of the Universe with look-back time are discussed.

</DOC>
<DOC>
<DOCNO> 9556 </DOCNO>
Many Body Problems with "Spin"-Related Contact Interactions


  We study quantum mechanical systems with "spin"-related contact interactions
in one dimension. The boundary conditions describing the contact interactions
are dependent on the spin states of the particles. In particular we investigate
the integrability of $N$-body systems with $\delta$-interactions and point spin
couplings. Bethe ansatz solutions, bound states and scattering matrices are
explicitly given. The cases of generalized separated boundary condition and
some Hamiltonian operators corresponding to special spin related boundary
conditions are also discussed.

</DOC>
<DOC>
<DOCNO> 150485 </DOCNO>
Collapsing D-branes in one-parameter models and small/large radius


  We finalize the study of collapsing D-branes in one-parameter models by
completing the analysis of the associated hypergeometric hierarchy. This brings
further evidence that the phenomenon of collapsing 6-branes at the mirror of
the `conifold' point in IIA compactifications on one-parameter Calabi-Yau
manifolds is generic. It also completes the reduction of the study of higher
periods in one-parameter models to a few families which display characteristic
behaviour. One of the models we consider displays an exotic form of small-large
radius duality, which is a consequence of an ``accidental'' discrete symmetry
of its moduli space. We discuss the implementation of this symmetry at the
level of the associated type II string compactification and its action on
D-brane states. We also argue that this model admits two special Lagrangian
fibrations and that the symmetry can be understood as their exchange.

</DOC>
<DOC>
<DOCNO> 120979 </DOCNO>
New VLBI Constraints for 0957+561 Lens Models


  Time-delay measurements of 0957+561 based on radio monitoring now agree with
optical monitoring. Recent models incorporate many recent observations, but the
systematic uncertainties in the models still dominate the uncertainty in the
cosmological results. VLBI observations of the milli-arcsec jet structure have
provided the most important set of modeling constraints. We present new
observations of this structure, made at 18 cm with the Very Long Baseline
Array, the Very Large Array, and the Green Bank 140 ft. telescope. Compared to
the data set of Garrett et al. (1994), ours has a similar theoretical noise
level (20 microJy), but nearly twice as many baselines (66 compared to 36) and
more uniform coverage of the UV plane. Our initial maps confirm the basic jet
structures seen by Garrett et al., with comparable RMS noise (60-80 microJy),
and are in reasonable agreement with the jet structure model of Barkana et al.
(1999). The maps also hint at a new compact component leaving the core, and a
previously undetected diffuse component at the end of the jet. Further
refinements in fringe-fitting, mapping, and self-calibration should yield
significantly lower RMS noise (closer to the theoretical level). We will use a
modified form of the CalTech VLBI Modelfit program (written by Barkana et al.
1999) to determine the magnification matrix between the images. The refined
magnification matrix should provide stronger constraints on the lens model, and
thus reduce the uncertainty in the cosmological results.

</DOC>
<DOC>
<DOCNO> 72250 </DOCNO>
HERWIG for Top Physics at the Linear Collider


  We discuss recent improvement in the treatment of gluon radiation in top
production and decay in e+e- processes according to the HERWIG event generator
and show studies on the top mass reconstruction at the future Linear Collider.

</DOC>
<DOC>
<DOCNO> 152548 </DOCNO>
Gravitational domain walls and p-brane distributions


  We review the main algebraic aspects that characterize and determine the
domain wall solutions of maximal gauged supergravity in various spacetime
dimensions by considering consistent truncations that retain a number of
components in the diagonal of the coset space scalar manifold of the theory.
Starting from the algebraic classification of domain walls in D=4 gauged
supergravity, we also derive the corresponding solutions in D=5 and D=7
dimensions. From a higher dimensional point of view, these solutions describe
the gravitatonal field, in the field theory limit, of a large number of M2-,
D3- and M5-branes that are distributed on hypersurfaces in the transverse space
to the branes. As a new result we employ a smearing procedure as well as
various dualities to list the irreducible curves and the symmetry groups of
p-brane distributions for all values of p that are of interest in current
applications of string theory. Some emphasis is placed on the presentation of
new results in the case of NS5-branes.

</DOC>
<DOC>
<DOCNO> 11564 </DOCNO>
Power-laws in economy and finance: some ideas from physics


  We discuss several models in order to shed light on the origin of power-law
distributions and power-law correlations in financial time series. From an
empirical point of view, the exponents describing the tails of the price
increments distribution and the decay of the volatility correlations are rather
robust and suggest universality. However, many of the models that appear
naturally (for example, to account for the distribution of wealth) contain some
multiplicative noise, which generically leads to *non universal exponents*.
Recent progress in the empirical study of the volatility suggests that the
volatility results from some sort of multiplicative cascade. A convincing
`microscopic' (i.e. trader based) model that explains this observation is
however not yet available. It would be particularly important to understand the
relevance of the pseudo-geometric progression of natural human time scales on
the long range nature of the volatility correlations.

</DOC>
<DOC>
<DOCNO> 8298 </DOCNO>
Impurity spin magnetization of thin Fe doped Au films


  In order to probe the influence of the surface-induced anisotropy on the
impurity spin magnetization, we measure the anomalous Hall effect in thin AuFe
films at magnetic fields up to 15 T. The observed suppression of the anomalous
Hall resistivity at low fields as well as the appearance of a minimum in the
differential Hall resistivity at higher fields can be explained by our
theoretical model which takes into account the influence of a polycrystalline
film structure on the surface-induced anisotropy. Our results imply that the
apparent discrepancy between different experimental results for the size
effects in dilute magnetic alloys can be linked to a different microstructure
of the samples.

</DOC>
<DOC>
<DOCNO> 178471 </DOCNO>
Transition from hadronic to partonic interactions for a composite


  A simple model of a composite nucleon is developed in which a fermion and a
boson, representing quark and diquark constituents of the nucleon, form a bound
state owing to a contact interaction. Photon and pion couplings to the quark
provide vertex functions for the photon and pion interactions with the
composite nucleon. By a suitable choice of cutoff parameters of the model,
realistic electromagnetic form factors are obtained. When a pseudoscalar
pion-quark coupling is used, the pion-nucleon coupling is predominantly
pseudovector. A virtual photopion amplitude is considered in which there are
two types of contributions: hadronic contributions where the photon and pion
interactions have an intervening propagator of the nucleon or its excited
states, and contact-like contributions where the photon and pion interactions
occur within a single vertex. At large Q, the contact-like contributions are
dominant. The model nucleon exhibits scaling behavior in deep-inelastic
scattering and the normalization of the parton distribution provides a rough
normalization of the contact-like contributions. Calculations for the virtual
photopion amplitude are performed using kinematics appropriate to its
occurrence as a meson-exchange current in electron-deuteron scattering. The
results show that the contact-like terms can dominate the meson-exchange
current for Q > 1 GeV/c. There is a direct connection of the contact-like terms
to the off-forward parton distributions of the model nucleon.

</DOC>
<DOC>
<DOCNO> 101036 </DOCNO>
On the stability of periodic 2D Euler-alpha flows


  An explicit expression is obtained for the sectional curvature in the plane
spanned by two stationary flows, cos(k, x) and cos(l, x). It is shown that for
certain values of the wave vectors k and l the curvature becomes positive for
alpha > alpha_0, where 0 < alpha_0 < 1 is of the order 1/k. This suggests that
the flow corresponding to such geodesics becomes more stable as one goes from
usual Eulerian description to the Euler-alpha model.

</DOC>
<DOC>
<DOCNO> 67979 </DOCNO>
Towards a Many-Body Treatment of Hamiltonian Lattice SU(N) Gauge Theory


  We develop a consistent approach to Hamiltonian lattice gauge theory, using
the maximal-tree gauge. The various constraints are discussed and implemented.
An independent and complete set of variables for the colourless sector is
determined. A general scheme to construct the eigenstates of the electric
energy operator using a symbolic method is described. It is shown how the
one-plaquette problem can be mapped onto a N-fermion problem. Explicit
solutions for U(1), SU(2), SU(3), SU(4), and SU(5) lattice gauge theory are
shown.

</DOC>
<DOC>
<DOCNO> 39854 </DOCNO>
Renormalization-Group-Improved Effective Potential for the MSSM Higgs


  We perform a systematic study of the one-loop renormalization-group-improved
effective potential of the minimal supersymmetric extension of the Standard
Model (MSSM), including CP violation induced radiatively by soft trilinear
interactions related to squarks of the third generation. We calculate the
charged and neutral Higgs-boson masses and couplings, including the two-loop
logarithmic corrections that arise from QCD effects, as well as those
associated with the top- and bottom-quark Yukawa couplings. We also include the
potentially large two-loop non-logarithmic corrections induced by one-loop
threshold effects on the top- and bottom-quark Yukawa couplings, due to the
decoupling of the third-generation squarks. Within this minimal CP-violating
framework, the charged and neutral Higgs sectors become intimately related to
one another and therefore require a unified treatment. In the limit of a large
charged Higgs-boson mass, M_{H^+} >> M_Z, the lightest neutral Higgs boson
resembles that in the Standard Model (SM), and CP violation occurs only in the
heavy Higgs sector. Our analysis shows that sizeable radiative effects of CP
violation in the Higgs sector of the MSSM may lead to significant modifications
of previous studies for Higgs-boson searches at LEP2, the Tevatron and the LHC.
In particular, CP violation could enable a relatively light Higgs boson to
escape detection at LEP2.

</DOC>
<DOC>
<DOCNO> 67813 </DOCNO>
Cubic root of Klein-Gordon equation


  We construct new relativistic linear differential equation in $d$ dimensions
generalizing Dirac equation by employing the Clifford algebra of the cubic
polynomial associated to Klein-Gordon operator multiplied by the mass
parameter. Unlike the Dirac case where the spin content is unique and Lorentz
covariance is manifest, here the spin as well as Lorentz covariance of the
theory are related to the choice of representation of the Clifford algebra. One
of the considered explicit matrix representations gives rise to anyon-like
fields in $d=1+1$. Coupling to a U(1) gauge field is discussed and compared
with Dirac theory.

</DOC>
<DOC>
<DOCNO> 119375 </DOCNO>
The afterglow of the short/intermediate-duration gamma-ray burst GRB


  We present Ulysses and NEAR data from the detection of the short or
intermediate duration (2 s) gamma-ray burst GRB000301C (2000 March 1.41 UT).
The gamma-ray burst (GRB) was localised by the Inter Planetary Network (IPN)
and RXTE to an area of 50 arcmin^2. A fading optical counterpart was
subsequently discovered with the Nordic Optical Telescope (NOT) about 42h after
the burst. The GRB lies at the border between the long-soft and the short-hard
classes of GRBs. If GRB000301C belongs to the latter class, this would be the
first detection of an afterglow to a short-hard burst. We present UBRI and JHK
photometry from the time of the discovery until 11 days after the burst.
Finally, we present spectroscopic observations of the optical afterglow
obtained with the ESO VLT Antu telescope 4 and 5 days after the burst. The
optical light curve is consistent with being achromatic from 2 to 11 days after
the burst and exhibits a break. A broken power-law fit yields a shallow
pre-break decay power-law slope of a_1=-0.72+-0.06, a break time of
t_b=4.39+-0.26 days after the burst, and a post-break slope of a_2=-2.29+-0.17,
which is best explained by a sideways expanding jet in an ambient medium of
constant mean density. In the optical spectrum we find absorption features that
are consistent with FeII, CIV, CII, SiII and Ly-a at a redshift of
2.0404+-0.0008. We find evidence for a curved shape of the spectral energy
distribution of the observed afterglow. It is best fitted with a power-law
spectral distribution with index b~-0.7 reddened by an SMC-like extinction law
with A_V~0.1 mag. Based on the Ly-a absorption line we estimate the HI column
density to be log(N(HI))=21.2+-0.5. This is the first direct indication of a
connection between GRB host galaxies and Damped Ly-a Absorbers.

</DOC>
<DOC>
<DOCNO> 68288 </DOCNO>
Four-fermion production in electron-positron collisions with NEXTCALIBUR


  We introduce a new, fully massive, Monte Carlo program to compute all
four-fermion processes in electron-positron collisions, including Higgs
production. We outline our strategy for the matrix element evaluation, the
phase space generation and the implementation of the leading higher order
effects, and show, where available, comparisons with existing results.

</DOC>
<DOC>
<DOCNO> 99582 </DOCNO>
Non-commutative Pieri operators on posets


  We consider graded representations of the algebra NC of noncommutative
symmetric functions on the Z-linear span of a graded poset P. The matrix
coefficients of such a representation give a Hopf morphism from a Hopf algebra
HP generated by the intervals of P to the Hopf algebra of quasi-symmetric
functions. This provides a unified construction of quasi-symmetric generating
functions from different branches of algebraic combinatorics, and this
construction is useful for transferring techniques and ideas between these
branches. In particular we show that the (Hopf) algebra of Billera and Liu
related to Eulerian posets is dual to the peak (Hopf) algebra of Stembridge
related to enriched P-partitions, and connect this to the combinatorics of the
Schubert calculus for isotropic flag manifolds.

</DOC>
<DOC>
<DOCNO> 117091 </DOCNO>
Mathematical ultrashort-pulse laser physics


  The analytical and numerical approaches to the analysis of the
ultrashort-pulse solid-state lasers are presented. The unique self-consistent
method of the laser dynamics analysis is based on the symbolical, numerical,
programming, and graphical capacities of Maple 6. The algorithmization of the
basic conceptions as well as sophisticated research methods is of interest to
both students and experts in the laser physics and the nonlinear dynamics

</DOC>
<DOC>
<DOCNO> 84841 </DOCNO>
G\"{o}del Type solution with rotation, expansion and closed time-like


  We propose a time-varying parameter $\underline{\alpha}$ for G\"{o}del metric
and an energy momentum tensor corresponding to this geometry is found. To
satisfy covariance arguments time-varying gravitational and cosmological term
are introduced. The ``Einstein's equation'' for this special evolution for the
Universe are written down where expansion, rotation and closed time-like curves
appear as a combination between standard model, G\"{o}del and steady state
properties are obtained.

</DOC>
<DOC>
<DOCNO> 8392 </DOCNO>
c-Axis tunneling in YBa2Cu3O7-\delta/PrBa2Cu3O7-\delta superlattices


  In this work we report c-axis conductance measurements done on a superlattice
based on a stack of 2 layers YBa2Cu3O{7-\delta} and 7 layers
PrBa2Cu3O{7-\delta} (2:7). We find that these quasi-2D structures show no clear
superconducting coupling along the c-axis. Instead, we observe tunneling with a
gap of \Delta_c=5.0\pm 0.5 meV for the direction perpendicular to the
superconducting planes. The conductance spectrum show well defined
quasi-periodic structures which are attributed to the superlattice structure.
  From this data we deduce a low temperature c-axis coherence length of
\xi_c=0.24\pm 0.03 nm.

</DOC>
<DOC>
<DOCNO> 121496 </DOCNO>
A Submillimeter Selected Quasar in the Field of Abell 478


  We report the discovery of a z=2.83 quasar in the field of the cooling flow
galaxy cluster Abell 478. This quasar was first detected in a submm survey of
star forming galaxies at high redshifts, as the brightest source. We discuss
the optical spectrum and far-IR spectral energy distribution (SED) of this
object.

</DOC>
<DOC>
<DOCNO> 119140 </DOCNO>
The Origin of Star Formation Gradients in Rich Galaxy Clusters


  We examine the origin of clustercentric gradients in the star formation rates
and colors of rich cluster galaxies within the context of a simple model where
clusters are built through the ongoing accretion of field galaxies. The model
assumes that after galaxies enter the cluster their star formation rates
decline on a timescale of a few Gyrs, the typical gas consumption timescale of
disk galaxies in the field. Such behaviour might be expected if tides and ram
pressure strip off the gaseous envelopes that normally fuel star formation in
spirals over a Hubble time. Combining these timescales with mass accretion
histories derived from N-body simulations of cluster formation in a Lambda-CDM
universe, we reproduce the systematic differences observed in the color
distribution of cluster and field galaxies, as well as the strong suppression
of star formation in cluster galaxies and its dependence on clustercentric
radius. The simulations also indicate that a significant fraction of galaxies
beyond the virial radius of the cluster may have been within the main body of
the cluster in the past, a result that explains naturally why star formation in
the outskirts of clusters (and as far out as two virial radii) is
systematically suppressed relative to the field. The agreement with the data
beyond the cluster virial radius is also improved if we assume that stripping
happens within lower mass systems, before the galaxy is accreted into the main
body of the cluster. We conclude that the star formation rates of cluster
galaxies depend primarily on the time elapsed since their accretion onto
massive virialized systems, and that the cessation of star formation may have
taken place gradually over a few Gyrs.

</DOC>
<DOC>
<DOCNO> 71216 </DOCNO>
How Frustrated Strings Would Pull the Black Holes from the Centers of


  Recently Pen and Spergel (1997) have shown that a universe whose energy
density is dominated by a frustrated network of non-Abelian TeV-scale cosmic
strings could account for a broad class of cosmological observations. In this
paper we consider the effects of such a string network on the massive black
holes widely believed to inhabit the centers of many galaxies. As these black
holes traverse the universe together with their host galaxies, they would
intersect a large number of string segments. We argue that such segments would
become stuck to the black hole, and be stretched by the hole's motion.
Stretching the strings would cause significant deceleration of the black holes.
Although the black holes would probably not be removed from the galaxies
completely, they would be noticeably displaced from the galactic center of mass
-- by at least 5kpc. This displacement seems to be is contradiction to the
observational evidence.

</DOC>
<DOC>
<DOCNO> 40258 </DOCNO>
Flavor Decomposition of Nucleon Structure at a Neutrino Factory


  We explore the possibilities for measuring the quark content of the proton
and neutron using neutrino beams produced at a muon storage ring. Because of
the nature of the beams, small nuclear targets such as hydrogen and deuterium
can be considered, as well as polarized targets. The statistics expected from
these targets are calculated using nominal muon storage ring intensities, and
the resulting statistical errors on the numerous structure functions available
are given, for both polarized and unpolarized targets. It is shown that with a
relatively small target, the structure functions F_2, xF_3, xg_1 and xg_5 for
neutrinos and antineutrinos on protons and deuterium, either unpolarized or
polarized, could be determined with excellent precision over most of the
accessible kinematic range.

</DOC>
<DOC>
<DOCNO> 178854 </DOCNO>
Incorporating Radial Flow in the Lattice Gas Model for Nuclear


  We consider extensions of the lattice gas model to incorporate radial flow.
Experimental data are used to set the magnitude of radial flow. This flow is
then included in the Lattice Gas Model in a microcanonical formalism. For
magnitudes of flow seen in experiments, the main effect of the flow on
observables is a shift along the $E^*/A$ axis.

</DOC>
<DOC>
<DOCNO> 100098 </DOCNO>
Infinitely ramified Galois representations


  In this paper we show how to construct, for most p >= 5, two types of
surjective representations
  \rho:G_Q=Gal(\bar{Q}/Q) -> GL_2(Z_p)
  that are ramified at an infinite number of primes. The image of inertia at
almost all of these primes will be torsion-free. The first construction is
unconditional. The catch is that we cannot say whether
  \rho|_{G_p=Gal(\bar{Q_p}/Q_p)
  is crystalline or even potentially semistable. The second construction
assumes the Generalized Riemann Hypothesis (GRH). With this assumption we can
further arrange that \rho|_{G_p} is crystalline at p. We remark that
infinitely ramified *reducible* representations have been previously
constructed by more elementary means.

</DOC>
<DOC>
<DOCNO> 99574 </DOCNO>
A generalization of Cayley submanifolds


  Given a Kaehler manifold of complex dimension 4, we consider submanifolds of
(real) dimension 4, whose Kaehler angles coincide. We call these submanifolds
Cayley. We investigate some of their basic properties, and prove that (a) if
the ambient manifold is a Calabi-Yau, the minimal Cayley submanifolds are just
the Cayley submanifolds as defined by Harvey and Lawson; (b) if the ambient is
a Kaehler-Einstein manifold of non-zero scalar curvature, then minimal Cayley
submanifolds have to be either complex or Lagrangian.

</DOC>
<DOC>
<DOCNO> 122306 </DOCNO>
Does TV Col Have the longest Recorded Positive Superhumps?


  Re-examination of extensive photometric data of TV Col reveals evidence for a
permanent positive superhump. Its period (6.4 h) is 16 percent longer than the
orbital period and obeys the well known relation between superhump period
excess and binary period. At 5.5-h, TV Col has an orbital period longer than
any known superhumping cataclysmic variable and, therefore, a mass ratio which
might be outside the range at which superhumps can occur according to the
current theory. We suggest several solutions for this problem.

</DOC>
<DOC>
<DOCNO> 117228 </DOCNO>
Biot-Savart-like law in electrostatics


  The Biot-Savart law is a well-known and powerful theoretical tool used to
calculate magnetic fields due to currents in magnetostatics. We extend the
range of applicability and the formal structure of the Biot-Savart law to
electrostatics by deriving a Biot-Savart-like law suitable for calculating
electric fields. We show that, under certain circumstances, the traditional
Dirichlet problem can be mapped onto a much simpler Biot-Savart-like problem.
We find an integral expression for the electric field due to an arbitrarily
shaped, planar region kept at a fixed electric potential, in an otherwise
grounded plane. As a by-product we present a very simple formula to compute the
field produced in the plane defined by such a region. We illustrate the
usefulness of our approach by calculating the electric field produced by planar
regions of a few nontrivial shapes.

</DOC>
<DOC>
<DOCNO> 72083 </DOCNO>
Conference Summary - Beauty 2000


  I discuss some key issues covered at the Conference including physics goals,
current results on CKM angles, rare decays, status of $|V_{cb}|$ and
$|V_{ub}|$, CKM fits and progress on hardware.

</DOC>
<DOC>
<DOCNO> 119353 </DOCNO>
Low and High Ionization Absorption Properties of Mg II


  [Abridged] We examine a sample of 45 Mg II absorption-selected systems over
the redshift range 0.4 to 1.4. Mg II and Fe II absorption profiles were
observed at a resolution of ~6 km/s with HIRES/Keck. Lyman-alpha and C IV data
were measured in archival FOS/HST spectra (~230 km/s). We perform a
multivariate analysis of W(MgII), W(FeII), W(CIV) and W(Lya) (rest-frame)
equivalent widths and the Mg II kinematic spread. We find five categories of Mg
II absorbers: "Classic", "C IV-deficient", "Single/Weak", "Double", and
"DLA/HI-Rich". There is a strong connection between low-ionization kinematics
and the location of an absorber on the W(CIV)-W(MgII) plane. In most absorbers
a significant fraction of the C IV arises in a phase separate from Mg II. Many
of the C IV profiles are resolved in the FOS spectra due to velocity
structure.. For 16 galaxies, we compare the available absorption-line
properties (taken from Churchill et al. 2000, Paper I) to the galaxy properties
but find no significant (greater than 3-sigma) correlations, although several
suggestive trends are apparent. We compare the locations of our intermediate
redshift absorbers on the W(CIV)-W(MgII) plane with those of lower and higher
redshift data taken from the literature and find evidence for evolution that is
connected with the Mg II kinematics. We discuss the potential of using the
above categorizations of absorbers to understand the evolution in the
underlying physical processes giving rise to the gas and governing its
ionization phases and kinematics.

</DOC>
<DOC>
<DOCNO> 72223 </DOCNO>
Generalized Proper-Time Approach For The Case Of Broken Isospin Symmetry


  We present a derivation of the low-energy effective meson Lagrangian of the
Nambu -- Jona-Lasinio (NJL) model on the basis of Schwinger's proper-time
regularization of the one-loop fermion determinant. We consider the case in
which the $SU(2)\times SU(2)$ chiral symmetry of the NJL Lagrangian is broken
by the current quark mass matrix with $\hat{m}_u\ne\hat{m}_d$. The
non-degeneracy of $d$ and $u$ masses destroys one of the most crucial features
of the proper-time expansion -- the chiral-invariant structure of Seeley --
DeWitt coefficients. We show however that systematic resummations inside the
proper-time expansion are still possible and derive a result which is in full
agreement with the chiral Ward -- Takahashi identities.

</DOC>
<DOC>
<DOCNO> 11900 </DOCNO>
Local minimal energy landscapes in river networks


  The existence and stability of the universality class associated to local
minimal energy landscapes is investigated. Using extensive numerical
simulations, we first study the dependence on a parameter $\gamma$ of a partial
differential equation which was proposed to describe the evolution of a rugged
landscape toward a local minimum of the dissipated energy. We then compare the
results with those obtained by an evolution scheme based on a variational
principle (the optimal channel networks). It is found that both models yield
qualitatively similar river patterns and similar dependence on $\gamma$. The
aggregation mechanism is however strongly dependent on the value of $\gamma$. A
careful analysis suggests that scaling behaviors may weakly depend both on
$\gamma$ and on initial condition, but in all cases it is within observational
data predictions. Consequences of our results

</DOC>
<DOC>
<DOCNO> 68470 </DOCNO>
On the New Conditions for a Total Neutrino Conversion in a Medium


  We show that the arguments forming the basis for the claim that the
conditions for total neutrino conversion derived and studied in detail in [1,2]
``are just the conditions of the parametric resonance of neutrino oscillations
supplemented by the requirement that the parametric enhancement be complete'',
given in [4] have flaws which make the claim physically questionable. We show
also that in the case of the transitions in the Earth of the
Earth-core-crossing solar and atmospheric neutrinos the peaks in the relevant
transitions probabilities $P_{a b}$, associated with the new conditions, $max
P_{a b} = 1$, are of physical relevance - in contrast to what is suggested in
[4]. Actually, the enhancement of $P_{a b}$ in any region of the corresponding
parameter space are essentially determined by these absolute maxima of $P_{a
b}$. We comment on few other aspects of the results derived in [1,2,3] which
have been misunderstood and/or misinterpreted in [4].

</DOC>
<DOC>
<DOCNO> 11380 </DOCNO>
New Superhard Phases for 3D C60-based Fullerites


  We have explored new possible phases of 3D C60-based fullerites using
semiempirical potentials and ab-initio density functional methods. We have
found three closely related structures - two body centered orthorhombic and one
body centered cubic - having 52, 56 and 60 tetracoordinated atoms per molecule.
These 3D polymers result in semiconductors with bulk moduli near 300 GPa, and
shear moduli around 240 GPa, which make them good candidates for new low
density superhard materials.

</DOC>
<DOC>
<DOCNO> 9566 </DOCNO>
Absorption in periodic layered structures


  Photonic band structure of metal-dielectric and semiconductor-dielectric
layered structures are studied in the presence of a strong absorption. It is
shown that absorption can enlarge some gaps by as much as 50%.

</DOC>
<DOC>
<DOCNO> 70192 </DOCNO>
Electroweak effects in radiative B decays


  We compute the two-loop electroweak corrections to the radiative decays of
the B meson in the SM. Electroweak effects reduce the Wilson coefficient
C_7^eff(mw) by 2.6% for a light Higgs boson of about 100 GeV and are less
important for a heavier Higgs. The leading term of a heavy top expansion of our
result differs from the one obtained in the gaugeless approximation where only
top quark Yukawa couplings are considered: we discuss the origin of the
discrepancy and provide a criterion for the validity of the gaugeless
approximation. As a byproduct of the calculation we also obtain the O(alpha)
corrections to the Wilson coefficient of the four-fermion operator Q_2. A
careful analysis of the interplay between electroweak and QCD effects leads to
an overall 2% reduction of the total branching ratio for B -> X_s gamma due to
purely electroweak corrections. For a light Higgs boson, the up-to-date SM
prediction is BR_gamma=3.29 10^-4.

</DOC>
<DOC>
<DOCNO> 70769 </DOCNO>
Indirect Violation of CP, T and CPT in the Bd-system


  The problem of indirect violation of discrete symmeties CP, T and CPT in a
neutral meson system can be described using two complex parameters epsilon and
delta, which are invariant under rephasing of meson and quark fields. For the
Bd system, where the width difference between the physical states is
negligible, only Re(delta) and Im(epsilon) survive. As a consequence, the
traditional observables constructed for kaons, which are based on flavour tag,
are not useful for the analogous study in this system. We describe how using a
CP tag and studying CP-to-flavour transitions of the B mesons, we may build
asymmetries, alternative to those used for the kaon, which enable us to test T
and CPT invariances of the effective hamiltonian for the Bd system.

</DOC>
<DOC>
<DOCNO> 101484 </DOCNO>
What is missing in canonical models for proper normal algebraic


  Smooth surfaces have finitely generated canonical rings and projective
canonical models. For normal surfaces, however, the graded ring of
multicanonical sections is possibly nonnoetherian, such that the corresponding
homogeneous spectrum is noncompact. I construct a canonical compactification by
adding finitely many non-Q-Gorenstein points at infinity, provided that each
Weil divisor is numerically equivalent to a Q-Cartier divisor. Similar results
hold for arbitrary Weil divisors instead of the canonical class.

</DOC>
<DOC>
<DOCNO> 12867 </DOCNO>
Classical Correlation-Length Exponent in Non-Universal Quantum Phase


  Critical behavior of the quantum phase transition of a site-diluted
Heisenberg antiferromagnet on a square lattice is investigated by means of the
quantum Monte Carlo simulation with the continuous-imaginary-time loop
algorithm. Although the staggered spin correlation function decays in a power
law with the exponent definitely depending on the spin size $S$, the
correlation-length exponent is classical, i.e., $\nu=4/3$. This implies that
the length scale characterizing the non-universal quantum phase transition is
nothing but the mean size of connected spin clusters.

</DOC>
<DOC>
<DOCNO> 100048 </DOCNO>
Zero divisors and L^p(G), II


  Let G be a discrete group, let $p \ge 1$, and let $L^p(G)$ denote the Banach
space $\{\sum_{g\in G} a_g g \mid \sum_{g\in G} |a_g|^p < \infty\}$. The
following problem will be studied: given $0 \ne \alpha \in CG$ and $0 \ne \beta
\in L^p(G)$, is $\alpha * \beta \ne 0$? We will concentrate on the case G is a
free abelian or free group.

</DOC>
<DOC>
<DOCNO> 119751 </DOCNO>
The X-ray transient XTE J1118+480: Multiwavelength observations of a


  We present multiwavelength observations of the newly discovered X-ray
transient XTE J1118+480 obtained in the rising phase of the 2000 April
outburst. This source is located at unusually high Galactic latitude and in a
very low absorption line of sight. This made the first EUVE spectroscopy of an
X-ray transient outburst possible. Together with our HST, RXTE, and UKIRT data
this gives unprecedented spectral coverage. We find the source in the low hard
state. The flat IR-UV spectrum appears to be a combination of optically thick
disk emission and flat spectrum emission, possibly synchrotron, while at higher
energies, including EUV, a typical low hard state power-law is seen. EUVE
observations reveal no periodic modulation, suggesting an inclination low
enough that no obscuration by the disk rim occurs. We discuss the nature of the
source and this outburst and conclude that it may be more akin to
mini-outbursts seen in GRO J0422+32 than to a normal X-ray transient outburst.

</DOC>
<DOC>
<DOCNO> 119629 </DOCNO>
Intrinsic Correlation of Galaxy Shapes: Implications for Weak Lensing


  Weak gravitational lensing is now established as a powerful method to measure
mass fluctuations in the universe. It relies on the measurement of small
coherent distortions of the images of background galaxies. Even low-level
correlations in the intrinsic shapes of galaxies could however produce a
significant spurious lensing signal. These correlations are also interesting in
their own right, since their detection would constrain models of galaxy
formation. Using $3\times 10^{4} - 10^5$ halos found in N-body simulations, we
compute the correlation functions of the intrinsic ellipticity of spiral
galaxies assuming that the disk is perpendicular to the angular momentum of the
dark matter halo. We also consider a simple model for elliptical galaxies, in
which the shape of the dark matter halo is assumed to be the same as that of
the light. For deep lensing surveys with median redshifts $\sim 1$, we find
that intrinsic correlations of $\sim 10^{-4}$ on angular scales $\theta \sim
0.1-10'$ are generally below the expected lensing signal, and contribute only a
small fraction of the excess signals reported on these scales. On larger scales
we find limits to the intrinsic correlation function at a level $\sim 10^{-5}$,
which gives a (model-dependent) range of separations for which the intrinsic
signal is about an order of magnitude below the ellipticity correlation
function expected from weak lensing. Intrinsic correlations are thus negligible
on these scales for dedicated weak lensing surveys. For wider but shallower
surveys such as SuperCOSMOS, APM and SDSS, we cannot exclude the possibility
that intrinsic correlations could dominate the lensing signal. We discuss how
such surveys could be used to calibrate the importance of this effect, as well
as study spin-spin correlations of spiral galaxies.

</DOC>
<DOC>
<DOCNO> 169672 </DOCNO>
Three-Qubit Gate Realization Using Single Quantum Particle


  Using virtual spin formalism it is shown that a quantum particle with eight
energy levels can store three qubits. The formalism allows to realize a
universal set of quantum gates. Feasible formalism implementation is suggested
which uses nuclear spin-7/2 as a storage medium and radio frequency pulses as
the gates. One pulse realization of all universal gates has been found,
including three-qubit Toffoli gate.

</DOC>
<DOC>
<DOCNO> 102425 </DOCNO>
Products on MU-modules


  We use the new categories of spectra and MU-modules constructed by Elmendorf,
Kriz, Mandell and May to get improved results about multiplicative structures
on spectra such as P(n) and E(n), particularly in the case p=2.

</DOC>
<DOC>
<DOCNO> 152063 </DOCNO>
Towards an accurate determination of the critical exponents with the


  The determination of the critical exponents by means of the Exact
Renormalizion Group approach is still a topic of debate. The general flow
equation is by construction scheme independent, but the use of the truncated
derivative expansion generates a model dependence in the determination of the
universal quantities. We derive new nonperturbative flow equations for the
one-component, $Z_2$ symmetric scalar field to the next-to-leading order of the
derivative expansion by means of a class of proper time regulators. The
critical exponents $\eta$, $\nu$ and $\omega$ for the Wilson-Fisher fixed point
are computed by numerical integration of the flow equations, without resorting
to polynomial truncations. We show that by reducing the width of the cut-off
employed, the critical exponents become rapidly insensitive to the cut-off
width and their values are in good agreement with the results of entirely
different approaches.

</DOC>
<DOC>
<DOCNO> 123315 </DOCNO>
Fundamental States of Accretion/Jet Configuration and the Black Hole


  Advective disk paradigm of black hole accretion includes self-consistent
formation of shocks and outflows from post-shock region. We apply this paradigm
to understand rich variation of the light curve of the black hole candidate
GRS1915+105. We propose that out of five possible {\it fundamental states} the
black hole candidate GRS1915+105 moves around among three of them creating all
possible observed light curves.

</DOC>
<DOC>
<DOCNO> 120559 </DOCNO>
The Cold and Hot Gas Content of Fine-Structure E and S0 Galaxies


  We investigate trends of the cold and hot gas content of early-type galaxies
with the presence of optical morphological peculiarities, as measured by the
fine-structure index (Sigma). HI mapping observations from the literature are
used to track the cold-gas content, and archival ROSAT PSPC data are used to
quantify the hot-gas content. We find that E and S0 galaxies with a high
incidence of optical peculiarities are exclusively X-ray underluminous and,
therefore, deficient in hot gas. In contrast, more relaxed galaxies with little
or no signs of optical peculiarities span a wide range of X-ray luminosities.
That is, the X-ray excess anticorrelates with Sigma. There appears to be no
similar trend of cold-gas content with either fine-structure index or X-ray
content. The fact that only apparently relaxed E and S0 galaxies are strong
X-ray emitters is consistent with the hypothesis that after strong disturbances
such as a merger hot-gas halos build up over a time scale of several gigayears.
This is consistent with the expected mass loss from stars.

</DOC>
<DOC>
<DOCNO> 178801 </DOCNO>
Bubble Nuclei, Neutron Stars and Quantum Billiards


  We briefly review the significance of quantum corrections in the total energy
of systems with voids: bubble nuclei, atomic clusters and the inhomogeneous
phase of neutron stars.

</DOC>
<DOC>
<DOCNO> 11464 </DOCNO>
SDW and FISDW transition of (TMTSF)$_2$ClO$_4$ at high magnetic fields


  The magnetic field dependence of the SDW transition in (TMTSF)$_2$ClO$_4$ for
various anion cooling rates has been measured, with the field up to 27T
parallel to the lowest conductivity direction $c^{\ast}$. For quenched
(TMTSF)$_2$ClO$_4$, the SDW transition temperature $T_{\rm {SDW}}$ increases
from 4.5K in zero field up to 8.4K at 27T. A quadratic behavior is observed
below 18T, followed by a saturation behavior. These results are consistent with
the prediction of the mean-field theory. From these behaviors, $T_{\rm {SDW}}$
is estimated as $T_{\rm {SDW_0}}$=13.5K for the perfect nesting case. This
indicates that the SDW phase in quenched (TMTSF)$_2$ClO$_4$, where $T_{\rm
{SDW}}$ is less than 6K, is strongly suppressed by the two-dimensionality of
the system. In the intermediate cooled state in which the SDW phase does not
appear in zero field, the transition temperature for the field-induced SDW
shows a quadratic behavior above 12T and there is no saturation behavior even
at 27T, in contrast to the FISDW phase in the relaxed state. This behavior can
probably be attributed to the difference of the dimerized gap due to anion
ordering.

</DOC>
<DOC>
<DOCNO> 70715 </DOCNO>
Maximum lepton asymmetry from active-sterile neutrino oscillations in


  A large lepton asymmetry could be generated in the Early Universe by
oscillations of active to sterile neutrinos with a small mixing angle sin 2
\theta < 10^-2. The final order of magnitude of the lepton asymmetry \eta is
mainly determined by its growth in the last stage of evolution when the MSW
resonance dominates the kinetic equations. In this paper we present a simple
way of calculating the maximum possible lepton asymmetry which can be created.
Our results are in good agreement to previous calculations. Furthermore, we
find that the growth of asymmetry does not obey any particular power law. We
find that the maximum possible asymmetry at the freeze-out of the n/p ratio at
T \sim 1 MeV strongly depends on the mass-squared difference \delta m^2: the
asymmetry is negligible for \delta m^2 \ll 1 eV^2 and reaches asymptotically
large values for \delta m^2 \ge 50 eV^2.

</DOC>
<DOC>
<DOCNO> 72308 </DOCNO>
Neutrino Masses and SO(10) SUSY GUTs


  In this talk I discuss the qualitative features of an SO(10) SUSY GUT with an
SU(2)x U(1)$^n$ family symmetry. I then describe the global fit of this theory
to precision electroweak data [including charged fermion masses and mixing
angles]. Finally, the predictions of the model for neutrino masses and mixing
are discussed. The most predictive version of the model naturally fits
atmospheric neutrino data with maximal $\nu_\mu \longrightarrow \nu_\tau$
oscillations and solar neutrino data with small mixing angle MSW $\nu_e
\longrightarrow \nu_{sterile}$ oscillations.

</DOC>
<DOC>
<DOCNO> 122057 </DOCNO>
Maximum Likelihood Estimates of the Two- and Three-Dimensional Power


  We estimate the two- and three-dimensional power spectra, P_2(K) and P_3(k),
of the galaxy distribution by applying a maximum likelihood estimator to pixel
maps of the APM Galaxy Survey. The analysis provides optimal estimates of the
power spectra and of their covariance matrices if the fluctuations are assumed
to be Gaussian. Our estimates of P_2(K) and P_3(k) are in good agreement with
previous work but we find that the errors at low wavenumbers have been
underestimated in some earlier studies. If the galaxy power spectrum is assumed
to have the same shape as the mass power spectrum, then the APM maximum
likelihood P_3(k) estimates at k < 0.19 h Mpc^-1 constrain the amplitude and
shape parameter of a scale-invariant CDM model to lie within the 2 sigma ranges
0.78 < sigma_8_g < 1.18 and 0.05 < Gamma < 0.38. Using the Galactic extinction
estimates of Schlegel, Finkbeiner and Davis, we show that Galactic obscuration
has a negligible effect on galaxy clustering over most of the area of the APM
Galaxy Survey.

</DOC>
<DOC>
<DOCNO> 12919 </DOCNO>
Jellium surface energy beyond the local-density approximation:


  We report extensive self-consistent calculations of jellium surface energies,
by going beyond the local-density approximation. The density-response function
of a bounded free-electron gas is evaluated within the random-phase
approximation, with use of self-consistent electron density profiles. The
exchange-correlation energy is then obtained from an exact adiabatic
fluctuation-dissipation formula. We also investigate quantum-size effects and
the extrapolation of finite-slab calculations to the infinite-width limit.

</DOC>
<DOC>
<DOCNO> 121861 </DOCNO>
Low and intermediate-mass close binary evolution and the initial - final


  Using Eggleton's stellar evolution code, we carry out 150 runs of Pop I
binary evolution calculations, with the initial primary mass between 1 and 8
solar masses the initial mass ratio between 1.1 and 4, and the onset of Roche
lobe overflow (RLOF) at an early, middle, or late Hertzsprung-gap stage. We
assume that RLOF is conservative in the calculations, and find that the remnant
mass of the primary may change by more than 40 per cent over the range of
initial mass ratio or orbital period, for a given primary mass. This is
contrary to the often-held belief that the remnant mass depends only on the
progenitor mass if mass transfer begins in the Hertzsprung gap. We fit a
formula, with an error less than 3.6 per cent, for the remnant (white dwarf)
mass as a function of the initial mass of the primary, the initial mass ratio,
and the radius of the primary at the onset of RLOF. We also find that a
carbon-oxygen white dwarf with mass as low as 0.33 solar masses may be formed
if the primary's initial mass is around 2.5 solar masses.

</DOC>
<DOC>
<DOCNO> 169726 </DOCNO>
NMR Quantum Computation: a Critical Evaluation


  Liquid state nuclear magnetic resonance (NMR) techniques have produced some
spectacular successes in the construction of small quantum computers, and NMR
is currently by far the leading technology for quantum computation. There are,
however, a number of significant problems with any attempt to scale up the
technology to produce computers of any useful size. While it is probable that
some of these will be successfully sidestepped during the next few years, it is
unlikely that they will all be solved; thus current liquid state NMR techniques
are unlikely to provide a viable technology for practical quantum computation.

</DOC>
<DOC>
<DOCNO> 151959 </DOCNO>
Quantum and Classical Gauge Symmetries


  The use of the mass term of the gauge field as a gauge fixing term, which was
discussed by Zwanziger, Parrinello and Jona-Lasinio in a large mass limit, is
related to the non-linear gauge by Dirac and Nambu. We have recently shown that
this use of the mass term as a gauge fixing term is in fact identical to the
conventional local Faddeev-Popov formula without taking a large mass limit, if
one takes into account the variation of the gauge field along the entire gauge
orbit. This suggests that the classical massive vector theory, for example,
could be re-interpreted as a gauge invariant theory with a gauge fixing term
added in suitably quantized theory.
 As for massive gauge particles, the Higgs mechanics, where the mass term is
gauge invariant, has a more intrinsic meaning. We comment on several
implications of this observation.

</DOC>
<DOC>
<DOCNO> 122585 </DOCNO>
Formation of a Massive Black Hole at the Center of the Superbubble in


  We performed 12CO(1-0), 13CO(1-0), and HCN(1-0) interferometric observations
of the central region (about 450 pc in radius) of M82 with the Nobeyama
Millimeter Array, and have successfully imaged a molecular superbubble and
spurs. The center of the superbubble is clearly shifted from the nucleus by 140
pc. This position is close to that of the massive black hole (BH) of >460 Mo
and the 2.2 micron secondary peak (a luminous supergiant dominated cluster),
which strongly suggests that these objects may be related to the formation of
the superbubble. Consideration of star formation in the cluster based on the
infrared data indicates that (1) energy release from supernovae can account for
the kinetic energy of the superbubble, (2) the total mass of stellar-mass BHs
available for building-up the massive BH may be much higher than 460 Mo, and
(3) it is possible to form the middle-mass BH of 100-1000 Mo within the
timescale of the superbubble. We suggest that the massive BH was produced and
is growing in the intense starburst region.

</DOC>
<DOC>
<DOCNO> 123207 </DOCNO>
An attempt to identify the extended synchrotron structure associated


  The energy ejected from the galaxy micro-quasar GRS1915+105 in the form of
jets is expected to lead to formation of an extended double lobe/hot-spot
structure with the energy content comparable to an average supernova remnant.
We used the Effelsberg 100m telescope at 10.45 GHz in attempt to identify such
structures. For this distant galactic plane source any definite identification
was not possible due to high confusion by numerous background sources, however,
a few suspect structures were pointed out.

</DOC>
<DOC>
<DOCNO> 8773 </DOCNO>
Tunnel splittings for one dimensional potential wells revisited


  The WKB and instanton answers for the tunnel splitting of the ground state in
a symmetric double well potential are both reduced to an expression involving
only the functionals of the potential, without the need for solving any
auxilliary problems. This formula is applied to simple model problems. The
prefactor for the splitting in the text book by Landau and Lifshitz is amended
so as to apply to the ground and low lying excited states.

</DOC>
<DOC>
<DOCNO> 72068 </DOCNO>
Physics Aspects of the CERN Heavy-Ion Programme


  Statistical calculations within the Standard Model indicate that at extremely
high densities the quarks and gluons will become deconfined, leading to a new
state of matter, the so-called Quark-Gluon Plasma (QGP). Recently it was
announced at CERN that compelling evidence has been obtained from experimental
data that indeed the formation of a deconfined state has been achieved in very
energetic collisions of heavy nuclei. In this presentation I will provide an
overview of the main aspects of heavy-ion physics and will address the various
observations which indicate the possible creation of a deconfined state. To
enable a systematic study of the QGP state, a combined measurement of the
various observables is needed. It will be shown how this can be realised within
the ALICE experiment at the future LHC collider.

</DOC>
<DOC>
<DOCNO> 100419 </DOCNO>
Local well-posedness of the Yang-Mills equation in the Temporal Gauge


  We show that the Yang-Mills equation in three dimensions is locally
well-posed in the Temporal gauge for initial data in H^s x H^{s-1} for s > 3/4,
if the norm of the initial data is sufficiently small.

</DOC>
<DOC>
<DOCNO> 150534 </DOCNO>
On Branes Ending on Branes in Supergravity


  We study the eleven-dimensional supergravity and the classical solutions
corresponding to M2-branes ending on M5-branes. We obtain the generic BPS
configuration representing two sets of parallel M5-branes with (1+1) commonly
longitudinal directions and M2-branes stretching between them. We also discuss
how the brane creation is described in supergravity.

</DOC>
<DOC>
<DOCNO> 118097 </DOCNO>
Radiation Spectra from Advection-Dominated Accretion Flows in a Global


  We calculate the radiation spectra from advection-dominated accretion flows
(ADAFs), taking into account the effects of a global magnetic field.
Calculation is based on the analytic model for magnetized ADAFs proposed by
Kaburaki, where a large-scale magnetic field controls the accretion process.
Adjusting a few parameters, we find that our model can well reproduce the
observed spectrum of Sagittarius A$^{*}$. The result is discussed in comparison
with those of well-known ADAF models, where the turbulent viscosity controls
the accretion process.

</DOC>
<DOC>
<DOCNO> 13183 </DOCNO>
On a correspondence between classical and quantum particle systems


  An exact correspondence is established between a $N$-body classical
interacting system and a $N-1$-body quantum system with respect to the
partition function. The resulting quantum-potential is a $N-1$-body one.
Inversely the Kelbg potential is reproduced which describes quantum systems at
a quasi-classical level. The found correspondence between classical and quantum
systems allows also to approximate dense classical many body systems by lower
order quantum perturbation theory replacing Planck's constant properly by
temperature and density dependent expressions. As an example the dynamical
behaviour of an one - component plasma is well reproduced concerning the
formation of correlation energy after a disturbance utilising solely the
analytical quantum - Born result for dense degenerated Fermi systems. As a
practical guide the quantum - Bruckner parameter $r_s$ has been replaced by the
classical plasma parameter $\Gamma$ as $r_s\approx0.3 \Gamma^{3/2}$

</DOC>
<DOC>
<DOCNO> 121987 </DOCNO>
Exploring the gravitationally lensed system HE1104-1805: VLT


  Using FORS2, mounted on Kueyen (UT2 of the VLT), we have obtained the
redshift of the lensing galaxy in the gravitational lens system HE1104-1805. We
measure z=0.729, in good agreement with previous estimates based on the time
delay and the position of the lens on the fundamental plane. It also coincides
with one of the metal line absorption systems that are seen in high resolution
spectra of HE1104-1805.

</DOC>
<DOC>
<DOCNO> 117734 </DOCNO>
Stellar Dynamics and the implications on the merger evolution in NGC6240


  We report near-infrared integral field spectroscopy of the luminous merging
galaxy NGC 6240. Stellar velocities show that the two K-band peaks separated by
1.6arcsec are the central parts of inclined, rotating disk galaxies with equal
mass bulges. The dynamical masses of the nuclei are much larger than the
stellar mass derived from the K-band light, implying that the progenitor
galaxies were galaxies with massive bulges. The K-band light is dominated by
red supergiants formed in the two nuclei in starbursts, triggered ~2x10^7 years
ago, possibly by the most recent perigalactic approach. Strong feedback effects
of a superwind and supernovae are responsible for a short duration burst
(~5x10^6 years) which is already decaying. The two galaxies form a
prograde-retrograde rotating system and from the stellar velocity field it
seems that one of the two interacting galaxies is subject to a prograde
encounter. Between the stellar nuclei is a prominent peak of molecular gas
(H_2, CO). The stellar velocity dispersion peaks there indicating that the gas
has formed a local, self-gravitating concentration decoupled from the stellar
gravitational potential. NGC 6240 has previously been reported to fit the
paradigm of an elliptical galaxy formed through the merger of two galaxies.
This was based on the near-infrared light distribution which follows a
r^1/4-law. Our data cast strong doubt on this conclusion: the system is by far
not relaxed, rotation plays an important role, as does self-gravitating gas,
and the near-infrared light is dominated by young stars.

</DOC>
<DOC>
<DOCNO> 71646 </DOCNO>
Instantons and color symmetry breaking in the vacuum


  The instanton interaction in QCD generates an effective potential for scalar
quark-antiquark condensates in the color singlet and octet channels. For three
light quark flavors the cubic term in this potential induces an octet
condensate and ``spontaneous breaking'' of color in the vacuum. Realistic
masses of the rho- and eta'-mesons are compatible with
renormalization-group-improved instanton perturbation theory.

</DOC>
<DOC>
<DOCNO> 72253 </DOCNO>
Optimized Perturbation Theory at Finite Temperature--- Two-Loop


  We study the optimized perturbation theory (OPT) at finite temperature, which
is a self-consistent resummation method. Firstly, we generalize the idea of the
OPT to optimize the coupling constant in lambda phi^4 theory, and give a proof
of the renormalizability of this generalized OPT. Secondly, the principle of
minimal sensitivity and the criterion of the fastest apparent convergence,
which are conditions to determine the optimal parameter values, are examined in
lambda phi^4 theory. Both conditions exhibit a second-order transition at
finite temperature with critical exponent beta = 0.5 in the two-loop
approximation.

</DOC>
<DOC>
<DOCNO> 152079 </DOCNO>
6D trace anomalies from quantum mechanical path integrals


  We use the recently developed dimensional regularization (DR) scheme for
quantum mechanical path integrals in curved space and with a finite time
interval to compute the trace anomalies for a scalar field in six dimensions.
This application provides a further test of the DR method applied to quantum
mechanics. It shows the efficiency in higher loop computations of having to
deal with covariant counterterms only, as required by the DR scheme.

</DOC>
<DOC>
<DOCNO> 152567 </DOCNO>
Bound States of D(2p)-D0 Systems and Supersymmetric p-Cycles


  We discuss some issues related to D(2p)-D0 branes with background magnetic
fluxes respectively, in a T-dual picture, Dp-Dp branes at angles. In
particular, we describe the nature of the supersymmetric bound states appearing
after tachyon condensation. We present a very elementary derivation of the
conditions to be satisfied by such general supersymmetric gauge configurations,
which are simply related by T-duality to the conditions for supersymmetric
p-cycles in C^p.

</DOC>
<DOC>
<DOCNO> 71308 </DOCNO>
Bosonic Topcolor


  A topcolor model is presented that contains both composite and fundamental
scalar fields. Strong dynamics accounts for most of the top quark mass and part
of the electroweak symmetry breaking scale. The fundamental scalar is weakly
coupled and transmits its share of electroweak symmetry breaking to the light
fermions. The model is allowed by the current experimental bounds, and can give
a potentially large contribution to $D^0-\bar{D^0}$ mixing.

</DOC>
<DOC>
<DOCNO> 70072 </DOCNO>
The soft-gluon current at one-loop order


  We study the soft limit of one-loop QCD amplitudes and we derive the
process-independent factorization formula that controls the singular behaviour
in this limit. This is obtained from the customary eikonal factorization
formula valid at tree (classical) level by introducing a generalized soft-gluon
current that embodies the quantum corrections. We compute the explicit
expression of the soft-gluon current at one-loop order. It contains purely
non-abelian correlations between the colour charges of each pair of
hard-momentum partons in the matrix element. This leads to colour correlations
between (two and) three hard partons in the matrix element squared. Exploiting
colour conservation, we recover QED-like factorization for the square of the
matrix elements with two and three hard partons.

</DOC>
<DOC>
<DOCNO> 119754 </DOCNO>
Dense gas in the dust lane of Centaurus A


  The interstellar medium of Centaurus A (NGC 5128) has been studied
extensively in recent years, using mostly molecular lines tracing low to medium
density gas (500 to several $10^3$ cm$^{-3}$). The amount and distribution of
the dense molecular gas was largely unknown. Here we present new millimeter
data of the HCN(1-0), CS(2-1), and CS(3-2) rotational transitions towards the
nearby radio galaxy Centaurus A observed with the SEST on La Silla, Chile. We
obtained spectra of the HCN(1-0) emission which traces dense 10$^4$ cm$^{-3}$
molecular gas at the center and along the prominent dust lane at offset
positions $\pm60^{\prime \prime}$ and $\pm100^{\prime \prime}$. We also
obtained a few spectra of CS(2-1) and (3-2) tracing densities of $\sim10^5$
cm$^{-3}$. The emission in these lines is weak and reaches a few mK at the
available angular resolutions of 54$^{\prime \prime}$ - 36$^{\prime \prime}$.
At the central position, the integrated intensity ratio I(HCN)/I(CO) peaks at
0.064, and decreases to $\sim$0.02 to 0.04 in the dust lane.

</DOC>
<DOC>
<DOCNO> 9989 </DOCNO>
On the "anomalous" resurgence of shot noise in long conductors


  There has been renewed interest in the physics of the so-called crossover for
current fluctuations in mesoscopic conductors, most recently involving the
possibility of its appearance in the passage to the macroscopic limit. Shot
noise is normally absent from solid-state conductors in the large, and its
anomalous resurgence there has been ascribed to a rich interplay of drift,
diffusion, and Coulomb screening. We demonstrate that essentially the same rise
in shot noise occurs in a much less complex system: the Boltzmann-Drude-Lorentz
model of a macroscopic, uniform gas of strictly noninteracting carriers. We
conclude that the "anomalous crossover" is a manifestation of simple kinetics.
Poissonian carriers, if driven by a high enough field, cross the sample faster
than any scattering time, thus fulfilling Schottky's condition for ideal shot
noise.

</DOC>
<DOC>
<DOCNO> 39698 </DOCNO>
Studies of Avalanche Photodiode Performance in a High Magnetic Field


  We report the results of exposing a Hamamatsu avalanche photodiode (APD) to a
7.9 Tesla magnetic field. The effect of the magnetic field on the gain of the
APD is shown and discussed. We find APD gain to be unaffected in the presence
of such a magnetic field.

</DOC>
<DOC>
<DOCNO> 100904 </DOCNO>
On the dual of complex Olshanskii semigroups


  Let $G$ be a connected Lie group and $\hat G$ its unitary dual. We are
interested in the part $\Lambda\subset\hat G$ which corresponds to the unitary
highest weight representations of $G$. Then there are several topologies on
$\Lambda$: The euclidean topology $T_E$ which comes from the identification of
$\Lambda$ with the set of highest weights, the induced topology $T_I$ induced
from the Fell topology on $\hat G$ and finally a natural topology $T_S$ which
comes from the hull kernel topology of certain CCR C^*-algebras which are
related to the holomorphic extemsion of unitary highest weight representations
to complex Olshanskii semigroups $S$. One of the main results in this paper is
the inclusion chain $T_S\subset T_I\subset T_E$. Further we exhibit very large
interesting subspaces of $\Lambda$ where these topologies coincide. Finally we
show that the Borel structures on $\Lambda$ induced from the three different
topologies coincide.

</DOC>
<DOC>
<DOCNO> 83096 </DOCNO>
Combining Random Number Generators using Quasicrystals


  This paper has been withdrawn by the author(s),

</DOC>
<DOC>
<DOCNO> 117871 </DOCNO>
Design optimization of MACHe3, a project of superfuid He3 detector for


  MACHe3 (MAtrix of Cells of superfluid He3) is a project of a new detector for
direct Dark Matter (DM) search. A cell of superfluid He3 has been developed and
the idea of using a large number of such cells in a high granularity detector
is proposed. This paper presents, after a brief description of the superfluid
He3 cell, the simulation of the response of different matrix configurations
allowing to define an optimum design as a function of the number of cells and
the volume of each cell. The background rejection, for several configurations,
is presented both for neutrons and gamma-rays of various kinetic energies.

</DOC>
<DOC>
<DOCNO> 12527 </DOCNO>
Detailed analysis of scanning tunneling microscopy images of the Si(001)


  The adequate interpretation of scanning tunneling microscopy (STM) images of
the clean Si(001) surface is presented. We have performed both STM observations
and {\it ab initio} simulations of STM images for buckled dimers on the clean
Si(001) surface. By comparing experimental results with theoretical ones, it is
revealed that STM images depend on the sample bias and the tip-sample
separation. This enables us to elucidate the relationship between the
corrugation in STM images and the atomic structure of buckled dimers. Moreover,
to elucidate these changes, we analyze details of the spatial distributions of
the $\pi$, $\pi^{\ast}$ surface states and $\sigma$, $\sigma^{\ast}$ Si-Si bond
states in the local density of states which contribute to STM images.

</DOC>
<DOC>
<DOCNO> 10046 </DOCNO>
Dispersion Relations in Ultradegenerate Relativistic Plasmas


  The propagation of excitation modes in a relativistic ultradegenerate plasma
is modified by their interactions with the medium. These modifications can be
computed by evaluating their on-shell self-energy, which gives
(gauge-independent) dispersion relations. For modes with momentum close to the
Fermi momentum, the one-loop fermion self-energy is dominated by a diagram with
a soft photon in the loop. We find the one-loop dispersion relations for
quasiparticles and antiquasiparticles, which behave differently as a
consequence of their very different phase-space restrictions when they scatter
with the electrons of the Fermi sea. In a relativistic system, the unscreened
magnetic interactions spoil the normal Fermi liquid behavior of the plasma. For
small values of the Fermi velocity, we recover the non-relativistic dispersion
relations of condensed matter systems.

</DOC>
<DOC>
<DOCNO> 173957 </DOCNO>
Hilbert C*-systems for actions of the circle group


  The paper contains constructions of Hilbert systems for the action of the
circle group $T$ using subgroups of implementable Bogoljubov unitaries w.r.t.
Fock representations of the Fermion algebra for suitable data of the selfdual
framework: ${\cal H}$ is the reference Hilbert space, $\Gamma$ the conjugation
and $P$ a basis projection on ${\cal H}.$ The group $C({spec} {\cal Z}\to T)$
of $T$-valued functions on ${spec} {\cal Z}$ turns out to be isomorphic to the
stabilizer of ${\cal A}$. In particular, examples are presented where the
center ${\cal Z}$ of the fixed point algebra ${\cal A}$ can be calculated
explicitly.

</DOC>
<DOC>
<DOCNO> 9191 </DOCNO>
The onset of exciton absorption in modulation doped GaAs quantum wells


  We study the evolution of the absorption spectrum of a modulation doped
GaAs/AlGaAs semiconductor quantum well with decreasing the carrier density. We
find that there is a critical density which marks the transition from a Fermi
edge singularity to a hydrogen-like behavior. At this density both the
lineshape and the transitions energies of the excitons change. We study the
density dependence of the singularity exponent $\alpha $ and show that disorder
plays an important role in determining the energy scale over which it grows.

</DOC>
<DOC>
<DOCNO> 116589 </DOCNO>
Optical and evaporative cooling of cesium atoms in the gravito-optical


  We report on cooling of an atomic cesium gas closely above an evanescent-wave
atom mirror. At high densitities, optical cooling based on inelastic
reflections is found to be limited by a density-dependent excess temperature
and trap loss due to ultracold collisions involving repulsive molecular states.
Nevertheless, very good starting conditions for subsequent evaporative cooling
are obtained. Our first evaporation experiments show a temperature reduction
from 10muK down to 300nK along with a gain in phase-space density of almost two
orders of magnitude.

</DOC>
<DOC>
<DOCNO> 123277 </DOCNO>
[O II] as a tracer of current star formation


  [O II] lambda 3727 Angstrom is often used as a tracer of star formation at
intermediate redshifts (z > 0.4), where Halpha is not easily observed. We use
the spectrophotometric data of the Nearby Field Galaxy Survey to investigate
the range and systematic variation in observed [O II]/Halpha emission line
ratio as a function of galaxy luminosity at low redshift. We find that the
observed [O II]/Halpha ratio varies by a factor of 7 at luminosities near M_B*.
The [O II]/Halpha ratio is inversely correlated with luminosity. The scatter in
the [O II]/Halpha ratio and the dependence of the ratio on luminosity are due
in equal parts to reddening and to the metallicity dependent excitation of the
ISM. The uncertainty in star formation rates derived from [O II] fluxes is
therefore large. If Halpha cannot be observed, high S/N Hbeta fluxes are much
preferable to [O II] fluxes for deriving star formation rates. We present
several purely empirical corrections for extinction.

</DOC>
<DOC>
<DOCNO> 120179 </DOCNO>
Orbital Dynamics of Triaxial Black-Hole Nuclei


  Orbital motion in triaxial nuclei with central point masses, representing
supermassive black holes, is investigated. The stellar density is assumed to
follow a power law, rho ~ 1/r^gamma, with gamma=1 or gamma=2. At low energies
the motion is essentially regular; the major families of orbits are the tubes
and the pyramids. Pyramid orbits are similar to box orbits but have their major
elongation parallel to the short axis of the figure. A number of regular orbit
families associated with resonances also exist, most prominently the banana
orbits, which are also elongated with the short axis. At a radius where the
enclosed stellar mass is a few times the black hole mass, the pyramid orbits
become stochastic. The energy of transition to this ``zone of chaos'' is
computed as a function of gamma and of the shape of the stellar figure; it
occurs at lower energies in more elongated potentials. Our results suggest that
supermassive black holes may place tight constraints on departures from
triaxiality in galactic nuclei, both by limiting the allowed shapes of regular
orbits and by inducing chaos.

</DOC>
<DOC>
<DOCNO> 100936 </DOCNO>
A Large Dihedral Symmetry of the Set of Alternating Sign Matrices


  We prove a conjecture of Cohn and Propp, which refines a conjecture of Bosley
and Fidkowski about the symmetry of the set of alternating sign matrices
(ASMs). We examine data arising from the representation of an ASM as a
collection of paths connecting 2n vertices and show it to be invariant under
the dihedral group D_{2n} rearranging those vertices, which is much bigger than
the group of symmetries of the square. We also generalize conjectures of Propp
and Wilson relating some of this data for different values of n.

</DOC>
<DOC>
<DOCNO> 178969 </DOCNO>
Low lying $qqqq\bar q$ states in the baryon spectrum


  The coupling to light mesons leads to large widths and shifts of the energy
of the excited states in the baryon spectrum from the predictions of the
constituent quark model with three valence quarks. This coupling may be
modelled by admixtures of sea-quark $qqq(q\bar q)^n$ configurations in the
resonances. A schematic flavor and spin dependent interaction model, similar to
the one which reproduces the low lying part of the experimental baryon spectrum
in the valence quark model, is shown to bring the lowest $qqqq\bar q$ states
with L=1 and positive parity below the states with L=0. Because of the partial
overlap with the corresponding $qqq$ states this suggests that most of the low
lying states in the baryon resonance spectrum have substantial $qqqq\bar q$
admixtures.

</DOC>
<DOC>
<DOCNO> 121568 </DOCNO>
MACS: A quest for the most massive galaxy clusters in the universe


  We describe the design and current status of a new X-ray cluster survey aimed
at the compilation of a statistically complete sample of very X-ray luminous
(and thus, by inference, massive), distant clusters of galaxies. The primary
goal of the MAssive Cluster Survey (MACS) is to increase the number of known
massive clusters at z>0.3 from a handful to hundreds. Upon completion of the
survey, the MACS cluster sample will greatly improve our ability to study
quantitatively the physical and cosmological parameters driving cluster
evolution at redshifts and luminosities poorly sampled by all existing surveys.
  To achieve these goals we apply an X-ray flux and X-ray hardness-ratio cut to
select distant cluster candidates from the ROSAT Bright Source Catalogue.
Starting from a list of more than 5,000 X-ray sources within the survey area of
22,735 square degrees we use positional cross-correlations with public
catalogues of Galactic and extragalactic objects, reference to APM colours,
visual inspection of Digitized Sky Survey images, extensive CCD imaging, and
finally spectroscopic observations with the University of Hawaii's 2.2m and the
Keck 10m telescopes to compile the final cluster sample.
  We discuss in detail the X-ray selection procedure and the resulting
selection function, and present model predictions for the number of distant
clusters expected to emerge from MACS. At the time of this writing the MACS
cluster sample comprises 101 spectroscopically confirmed clusters at 0.3<z<0.6;
more than two thirds of these are new discoveries. Our preliminary sample is
already 15 times larger than that of the EMSS in the same redshift and X-ray
luminosity range.

</DOC>
<DOC>
<DOCNO> 99711 </DOCNO>
A Willmore functional for compact surfaces of complex projective plane


  We propose the study of a conformally invariant functional for surfaces of
complex projective plane which is closely related to the classical Willmore
functional. We show that minimal surfaces of complex projective plane are
critical for this functional and construct some minima for it via the twistors
spaces of complex projective plane. Also, we find lower bounds for this
functional and for its restriction to the class of Lagrangian surfaces and
characterize the complex lines and the Lagrangian totally geodesic surfaces and
the Whitney spheres as the only attaining those bounds.

</DOC>
<DOC>
<DOCNO> 9538 </DOCNO>
Order of the phase transition in models of DNA thermal denaturation


  We examine the behavior of a model which describes the melting of
double-stranded DNA chains. The model, with displacement-dependent stiffness
constants and a Morse on-site potential, is analyzed numerically; depending on
the stiffness parameter, it is shown to have either (i) a second-order
transition with "nu_perpendicular" = - beta = 1, "nu_parallel" = gamma/2 = 2
(characteristic of short range attractive part of the Morse potential) or (ii)
a first-order transition with finite melting entropy, discontinuous fraction of
bound pairs, divergent correlation lengths, and critical exponents
"nu_perpendicular" = - beta = 1/2, "nu_parallel" = gamma/2 = 1.

</DOC>
<DOC>
<DOCNO> 123226 </DOCNO>
The effect of bias and redshift distortions on a geometric test for the


  We revisit the feasibility of a cosmological test with the geometric
distortion focusing on an ambiguous factor of the evolution of bias. Starting
from defining estimators for the spatial two-point correlation function and the
power spectrum, in a rigorous manner, we derive useful formulas for the
two-point clustering statistics which take the light-cone effect and the
redshift-space distortions into account. Then we investigate how the predicted
correlation functions are affected by the redshift-space distortions and the
bias assuming quasar samples which roughly match the 2dF survey. Effect of the
bias is crucial, in particular, on anisotropic component of the clustering
statistics in redshift-space. By surveying behavior of the predicted
correlation functions to parameters of a phenomenological model for the
evolution of bias, it is shown that the correlation functions on the light-cone
is sensitive to a mean amplitude of the bias and rather insensitive to the
speed of its redshift-evolution. This feature is useful for an analysis of the
geometric test.

</DOC>
<DOC>
<DOCNO> 117771 </DOCNO>
Optical/Multiwavelength Observations of GRB Afterglows


  I review gamma-ray burst optical/multiwavelength afterglow observations since
1997, when the first counterparts to GRBs were discovered. I discuss what we
have learned from multiwavelength observations of GRB afterglows in relation to
the `standard' fireball plus relativistic blast-wave models. To first order the
`standard' model describes the afterglow observations well, but a wealth of
information can be gathered from the deviations of GRB afterglow observations
from this `standard' model. These deviations provide information on the nature
of the progenitor and on the physics of GRB production. In particular I focus
on the possible connection of GRBs to supernovae, on jet and circumstellar wind
models, on the early-time afterglow, and on the emission from the reverse
shock.

</DOC>
<DOC>
<DOCNO> 99392 </DOCNO>
On infinite tensor products of projective unitary representations


  We initiate a study of infinite tensor products of projective unitary
representations of a discrete group G. Special attention is given to regular
representations twisted by 2-cocycles and to projective representations
associated with CCR-representations of bilinear maps. Detailed computations are
presented in the case where G is a finitely generated free abelian group. We
also discuss an extension problem about product type actions of G, where the
projective representation theory of G plays a central role.

</DOC>
<DOC>
<DOCNO> 10648 </DOCNO>
Has the FFLO state been observed in the organic superconductor


  We compare the theoretical anisotropic upper critical field $H_{C}(\Theta,T)$
of a quasi-two-dimensional d-wave superconductor with recent $H_{c2}$ data for
the layered organic superconductor $\kappa-(BEDT-TTF)_2Cu(NCS)_2$. We find
agreement both with regard to the angular and the temperature dependence of
$H_{C}$. This supports the suggestion that the Fulde-Ferrell-Larkin-Ovchinnikov
state (FFLO state) exists in this material for exactly plane-parallel
orientation of the magnetic field. Indications of precursor states, occurring
for small deviations from the plane-parallel field direction, are also pointed
out and further measurements for confirming the existence of the FFLO state are
proposed.

</DOC>
<DOC>
<DOCNO> 71282 </DOCNO>
A thought experiment with clocks in static gravity


  In order to directly demonstrate that in static gravitational field the rate
of clocks increases with their distance from the source a simple thought
experiment is proposed.

</DOC>
<DOC>
<DOCNO> 84837 </DOCNO>
Gauge symmetries of the teleparallel theory of gravity


  We study gauge properties of the general teleparallel theory of gravity,
defined in the framework of Poincare gauge theory. It is found that the general
theory is characterized by two kinds of gauge symmetries: a specific gauge
symmetry that acts on Lagrange multipliers, and the standard Poincare gauge
symmetry. The canonical generators of these symmetries are explicitly
constructed and investigated.

</DOC>
<DOC>
<DOCNO> 9076 </DOCNO>
Submillimeter spectroscopy of tilted Nd_{1.85}Ce_{0.15}CuO_{4-\delta}


  The anisotropic conductivity of a series of tilted
Nd_{1.85}Ce_{0.15}CuO_{4-\delta} thin films was measured by quasioptical
spectroscopy in the frequency range 3cm^{-1}<\nu <40cm^{-1}. Two characteristic
features have been observed in the low-temperature transmission spectra. The
first one at \nu = 12cm^{-1} was shown to reflect the c-axis plasma frequency
of Nd_{1.85}Ce_{0.15}CuO_{4-\delta}. The second feature represents a new mixed
ab-plane/c-axis excitation. The frequency of this resonance may be changed in a
controllable way by rotating the polarization of the incident radiation.

</DOC>
<DOC>
<DOCNO> 10521 </DOCNO>
Static Friction between Elastic Solids due to Random Asperities


  Several workers have established that the Larkin domains for two three
dimensional nonmetallic elastic solids in contact with each other at a
disordered interface are enormously large. This implies that there should be
negligible static friction per unit area in the macroscopic solid limit.
 The present work argues that the fluctuations in the heights of the random
asperities at the interface that occur in the Greenwood-Williamson model can
account for static friction.

</DOC>
<DOC>
<DOCNO> 10202 </DOCNO>
Stability of a Thin Solid Film with Interactions


  We investigate the question of stability of a solid thin film which
experiences external interactions such as van der Waals forces from a
contacting surface or forces from an external electric field. Both perfectly
elastic and viscoelastic material behaviours are considered in linear stability
analysis performed here. These analyses indicate that for sufficiently soft
(shear modulus between 1 and 10 MPa) and nearly incompressible films (Poisson's
ratio close to 0.5), bifurcations are possible, i.e., the surface of the film
becomes non-planar. The modes of bifurcation and rates of growth of
perturbations are determined as a function of material parameters. The results
of this study are of significance in understanding the adhesive properties
between a soft material (such as rubber) and a comparatively rigid solid (such
as steel), and the behaviour of soft solid films in an electric field.

</DOC>
<DOC>
<DOCNO> 83483 </DOCNO>
EquiX---A Search and Query Language for XML


  EquiX is a search language for XML that combines the power of querying with
the simplicity of searching. Requirements for such languages are discussed and
it is shown that EquiX meets the necessary criteria. Both a graphical abstract
syntax and a formal concrete syntax are presented for EquiX queries. In
addition, the semantics is defined and an evaluation algorithm is presented.
The evaluation algorithm is polynomial under combined complexity.
  EquiX combines pattern matching, quantification and logical expressions to
query both the data and meta-data of XML documents. The result of a query in
EquiX is a set of XML documents. A DTD describing the result documents is
derived automatically from the query.

</DOC>
<DOC>
<DOCNO> 10013 </DOCNO>
Fermi Surface Properties of Low Concentration Ce$_{x}$La$_{1-x}$B$_{6}$:


  The de Haas-van Alphen effect is used to study angular dependent extremal
areas of the Fermi Surfaces (FS) and effective masses of Ce$_{x}$La$_{1-x}$B$%
_{6}$ alloys for $x$ between 0 and 0.05. The FS of these alloys was previously
observed to be spin polarized at low Ce concentration ($x$ = 0.05). This work
gives the details of the initial development of the topology and spin
polarization of the FS from that of unpolarized metallic LaB$_{6}$ to that of
spin polarized heavy Fermion CeB$_{6}$ .

</DOC>
<DOC>
<DOCNO> 68670 </DOCNO>
Baryogenesis vs. proton stability in theories with extra dimensions


  We propose a new scenario of baryogenesis in the context of theories with
large extra dimensions. The baryon number is almost conserved at zero
temperature by means of a localization mechanism recently analyzed by
Arkani-Hamed and Schmaltz: leptons and quarks are located at two slightly
displaced positions in the extra space, and this naturally suppresses the
interactions which ``convert'' the latter in the former. We show that this is
expected to be no longer true when finite temperature effects are taken into
account. The whole scenario is first presented in its generality, without
referring to the bulk geometry or to the specific mechanism which may generate
the baryon asymmetry. As an example, we then focus on a baryogenesis model
reminiscent of GUT baryogenesis. The Sakharov out of equilibrium condition is
satisfied by assuming nonthermal production of the bosons that induce baryon
number violation.

</DOC>
<DOC>
<DOCNO> 11859 </DOCNO>
Crowd-Anticrowd Theory of Multi-Agent Market Games


  We present a dynamical theory of a multi-agent market game, the so-called
Minority Game (MG), based on crowds and anticrowds. The time-averaged version
of the dynamical equations provides a quantitatively accurate, yet intuitively
simple, explanation for the variation of the standard deviation (`volatility')
in MG-like games. We demonstrate this for the basic MG, and the MG with
stochastic strategies. The time-dependent equations themselves reproduce the
essential dynamics of the MG.

</DOC>
<DOC>
<DOCNO> 152412 </DOCNO>
A Linear-confined Particle and the Dirac Equation


  The model of a classical particle with the weak linear AAD potential is
subjected to path integral quantization. The light cone constraints and
peculiar properies of its internal variables permit to use in calculations
commutative dynamics and apply path integrals for a matrix form of the
transition amplitude. Quantization leads to description of a Dirac particle.

</DOC>
<DOC>
<DOCNO> 170392 </DOCNO>
A Variational Expansion for the Free Energy of a Bosonic System


  In this paper, a variational perturbation scheme for nonrelativistic
many-Fermion systems is generalized to a Bosonic system. By calculating the
free energy of an anharmonic oscillator model, we investigated this variational
expansion scheme for its efficiency. Using the modified Feynman rules for the
diagrams, we obtained the analytical expression of the free energy up to the
fourth order. Our numerical results at various orders are compared with the
exact and other relevant results.

</DOC>
<DOC>
<DOCNO> 85247 </DOCNO>
Model of Expansive Nondecelerativa Universe and unified approach to


  The contribution provides the backround of the model of Expansive
Nondecelerative Universe, rationalizes the introduction of Vaidya metrics
allowing thus to localize and quantify gravitational energy. A unifying
explanation of the fundamental physical interactions is accompanied by
demonstration of some consequences and predictions relating to cosmological
problems.

</DOC>
<DOC>
<DOCNO> 72133 </DOCNO>
On Supersymmetric Dark Matter


  The extra particles provided by Supersymmetry (SUSY) appear as natural
candidates for exotica such as the missing Dark Matter of the Universe. The
particle candidates for Dark Matter, and the basic elements of the minimal
supersymmetric extension of the Standard Model are reviewed. The needed
elements to compute the neutralino counting rate are given, considering new
Yukawa loop corrections to the neutralino-neutralino-Higgs boson couplings when
the neutralino is a Bino-like state. Including the new loop corrections in the
Bino limit, the counting rate is improved for several values of the soft
breaking supersymmetric parameters.

</DOC>
<DOC>
<DOCNO> 151118 </DOCNO>
U(1) gauge invariance from open string field theory


  The naive low energy effective action of the tachyon and the U(1) gauge field
obtained from string field theory does not correspond to the world volume
action of unstable branes in bosonic string theory. We show that there exists a
field redefinition which relates the gauge field and the tachyon of the string
field theory action to the fields in the world volume action of unstable
branes. We identify a string gauge symmetry which corresponds to the U(1) gauge
transformation. This is done to the first non-linear order in the fields. We
examine the vector fluctuations at the tachyon condensate till level (4,8).

</DOC>
<DOC>
<DOCNO> 151152 </DOCNO>
On the WKB quantum equivalence between diverse p-brane actions


  We consider an action for a closed, bosonic, p-brane, where the brane tension
is not an assigned parameter but rather it is induced by a maximal rank gauge
p-form. This model is classically equivalent to the Nambu--Goto/Howe-Tucker
model. We investigate how this classical equivalence can be implemented in the
path integral framework. For this purpose we adopt a ``first order''
integration procedure over gauge p-forms and a ``shortened'' Fadeev-Popov
procedure.

</DOC>
<DOC>
<DOCNO> 12530 </DOCNO>
Quantum Atomistic Solid-State Theory


  Postulates of the quantum atomistic solid-state theory (QUASST) have been
presented. QUASST is an extension of the crystal-field theory and is applicable
to compounds containing open-shell 3d, 4f and 5f atoms. QUASST points out the
existence in a solid of the atomic-like discrete electronic structure
determined by the crystal- field and spin-orbit interactions. This approach
unifies the description of 3d and 4f ions and allows to bridge the atomic
physics and the solid-state physics.

</DOC>
<DOC>
<DOCNO> 116944 </DOCNO>
Development of a Smart Modulator and Efficiency Evaluation of 500-GeV


  An e+e- linear collider at 500-GeV C.M. (center of mass) has been proposed as
a future accelerator. The C-band linear collider has more than a thousand
klystrons and matching modulators. The linear colliders require smart
modulators with high reliability, compact and simple configuration, and good
power efficiency. This study suggests solutions to problems expected in the
future linear colliders. A C-band smart modulator has been developed using a
constant-current inverter power supply. The smart modulator provides 350-kV
pulses of the pulse-to-pulse stability of 0.35%, the pulse-width of 4.35
microseconds, and the repetition rate of 50 Hz. We also investigated the power
efficiency for the C-band scheme. A pulse efficiency of 75% can be achieved by
an optimized pulse transformer and the RF phase modulation. With pulsed
klystrons of 60% power efficiency, it is possible to achieve the RF system
efficiency of 32% with the wall-plug power of 170 MW.

</DOC>
<DOC>
<DOCNO> 101060 </DOCNO>
On the regularity of varieties having an extremal secant line


  The Castelnuovo-Mumford regularity of varieties of degree r and dimension n
in the r-dimensional projective space that have an extremal secant line, is at
least d-r+n+1. We classify these varieties and show that their regularity is
exactly d-r+n+1, as predicted by the regularity conjecture.

</DOC>
<DOC>
<DOCNO> 117721 </DOCNO>
New Extreme Synchrotron BL Lac Objects


  We report on the BeppoSAX observations of four "extreme" BL Lacs, selected to
have high synchrotron peak frequencies. All have been detected also in the PDS
band. For 1ES 0120+340, PKS 0548-322 and H 2356-309 the spectrum is well fitted
by a convex broken power-law, thus locating the synchrotron peak around 1 - 4
keV. 1ES 1426+428 presents a flat energy spectral index (alpha_x= 0.92) up to
100 keV, thus constraining the synchrotron peak to lie near or above that
value. For their extreme properties, all sources could be strong TeV emitters.

</DOC>
<DOC>
<DOCNO> 120601 </DOCNO>
Interstellar Seeing. I. Superresolution Techniques Using Radio


  Interstellar scintillation can be used to probe transverse sizes of radio
sources on scales inaccessible to the nominal resolution of any terrestrial
telescope, e.g. $\lesssim 10^{-6}$ arc sec. Methodology is presented that
exploits this superresolution phenomenon for both single aperture and
interferometer observations. The treatment applies to the saturated
(strong-scattering) regime and holds for both thin screens and extended media.
A general signal model for radio sources is presented, {\it scintillated
amplitude modulated noise}, which applies to compact, incoherent synchrotron
sources such as AGNs and gamma-ray burst sources and also to known, coherent
sources such as masers and pulsars. The exact probability density function for
measured intensities and interferometric visibilities is obtained by solving a
general Fredholm problem. An approximate density function is also obtained by
using the equivalent number of degrees of freedom in scintillation modulations.
The scintillation modulation variance is presented, which includes the effects
of source structure and time-bandwidth averaging in the signal processing. Two
Bayesian methods are outlined for inferring the sizes of emission regions that
use first order statistics of the intensity and visibility. Intensity
cross-correlation methods for inferring source sizes are also given. Intensity
interferometry in the the radio context is compared to the optical intensity
interferometry of Hanbury-Brown and Twiss.

</DOC>
<DOC>
<DOCNO> 150503 </DOCNO>
Non-Linear Realization of ${\aleph_0}$-Extended Supersymmetry


  As generalizations of the original Volkov-Akulov action in four-dimensions,
actions are found for all space-time dimensions D invariant under N non-linear
realized global supersymmetries. We also give other such actions invariant
under the global non-linear supersymmetry. As an interesting consequence, we
find a non-linear supersymmetric Born-Infeld action for a non-Abelian gauge
group for arbitrary D and N, which coincides with the linearly supersymmetric
Born-Infeld action in D=10 at the lowest order. For the gauge group U({\cal N})
for M(atrix)-theory, this model has {\cal N}^2-extended non-linear
supersymmetries, so that its large {\cal N} limit corresponds to the infinitely
many (\aleph_0) supersymmetries. We also perform a duality transformation from
F_{\mu\nu} into its Hodge dual N_{\mu_1...\mu_{D-2}}. We next point out that
any Chern-Simons action for any (super)groups has the non-linear supersymmetry
as a hidden symmetry. Subsequently, we present a superspace formulation for the
component results. We further find that as long as superspace supergravity is
consistent, this generalized Volkov-Akulov action can further accommodate such
curved superspace backgrounds with local supersymmetry, as a super p-brane
action with fermionic kappa-symmetry. We further elaborate these results to
what we call `simplified' (Supersymmetry)^2-models, with both linear and
non-linear representations of supersymmetries in superspace at the same time.
Our result gives a proof that there is no restriction on D or N for global
non-linear supersymmetry. We also see that the non-linear realization of
supersymmetry in `curved' space-time can be interpreted as `non-perturbative'
effect starting with the `flat' space-time.

</DOC>
<DOC>
<DOCNO> 122410 </DOCNO>
First results from the BOOMERanG experiment


  We report the first results from the BOOMERanG experiment, which mapped at
90, 150, 240 and 410 GHz a wide (3%) region of the microwave sky with minimal
local contamination. From the data of the best 150 GHz detector we find
evidence for a well defined peak in the power spectrum of temperature
fluctuations of the Cosmic Microwave Background, localized at $\ell = 197 \pm
6$, with an amplitude of $(68 \pm 8) \mu K_{CMB}$. The location, width and
amplitude of the peak is suggestive of acoustic oscillations in the primeval
plasma. In the framework of inflationary adiabatic cosmological models the
measured spectrum allows a Bayesian estimate of the curvature of the Universe
and of other cosmological parameters. With reasonable priors we find $\Omega =
(1.07 \pm 0.06)$ and $n_s = (1.00 \pm 0.08)$ (68%C.L.) in excellent agreement
with the expectations from the simplest inflationary theories. We also discuss
the limits on the density of baryons, of cold dark matter and on the
cosmological constant.

</DOC>
<DOC>
<DOCNO> 71114 </DOCNO>
Probing For New Physics In J/$\Psi$ Decays


  Beijing Spectrometer (BES) at Beijing Electron Positron Collider (BEPC), IHEP
has accumulated 2.5 $\times 10^7$ J/$\Psi$ and plans to increase the number to
$10^8 \sim 10^9$ in the near future. In this paper I review and summarize the
recent studies on the possibilities of probing for new physics at BES. This
includes the theoretical works on and experimental attempt performed at BES in
searching for flavor changing neutral current, CP violation and lepton flavor
violation in the processes of J/$\Psi$ decays.

</DOC>
<DOC>
<DOCNO> 174595 </DOCNO>
Radioactive 7Be targets for measurements of the cross section of the


  The interpretation of the most recent solar neutrinos experiments requires a
good knowledge of the cross section of the reaction 7Be(p,gamma)8B at very
small energy (Ecm=18 keV). We have recently measured this cross section for
Ecm=0.35-1.4 MeV and for Ecm=0.112-0.190 MeV. We report here on the description
of the preparation of the radioactive targets of 7Be used in these experiments.

</DOC>
<DOC>
<DOCNO> 70918 </DOCNO>
1/N_c and epsilon'/epsilon


  We present a recent analysis of epsilon'/epsilon in the 1/N_c expansion. We
show that the 1/N_c corrections to the matrix element of Q_6 are large and
positive, indicating a Delta I = 1/2 enhancement similar to the one of Q_1 and
Q_2 which dominate the CP conserving amplitude. This enhances the CP ratio and
can bring the standard model prediction close to the measured value for central
values of the parameters. Several comments on the theoretical status of
epsilon'/epsilon and the errors in its calculation are given.

</DOC>
<DOC>
<DOCNO> 100234 </DOCNO>
Holomorphic bundles and Scalar Difference Operators: One-Point


  Commutative rings of one-dimensional difference operators of rank l>1 and
their deformations are effectively constructed. Our analytical constructions
are based on the so-called ''Tyurin parameters'' for the stable framed
holomorphic vector bundles over algebraic curves of the genus equal to g and
Chern number equal to lg. These parameters were heavily used by the present
authors already in 1978-80 for the differential operators. Their deformations
in the discrete case are governed by the 2D Toda Lattice hierarhy instead of
KP. New integrable systems appear here in the case l=2,g=1. The theory of
higher rank difference operators is much more rich than the rank one case where
only 2-point constructions on the spectral curve were used in the previous
literature (i.e. number of 'infinite points'' is equal to 2). One-point
constructions appear in this problem for every even rank l=2k. Only in this
case commutative rings depend on the functional parameters. Two-point
constructions will be studied in the next work: even for higher rank l>1 this
case can be solved in Theta-functions. It is not so for one-point constructions
with rank l>1.

</DOC>
<DOC>
<DOCNO> 117626 </DOCNO>
Metallicity in damped Lyman-alpha systems: evolution or bias?


  Assuming that damped Lyman-alpha(DLA) systems are galactic discs, we
calculate the corresponding evolution of metal abundances. We use detailed
multi-zone models of galactic chemical evolution (reproducing successfully the
observed properties of disc galaxies) and appropriate statistics (including
geometrical propability factors) to calculate the average metallicity as a
function of redshift. The results are compatible with available observations,
provided that observational biases are taken into account, as suggested by
Boisse et al. (1998). In particular, high column density and high metallicity
systems are not detected because the light of backround quasars is severely
extinguished, while low column density and low metallicity systems are not
detectable through their absorption lines by current surveys. We show that
these observational constraints lead to a ``no-evolution'' picture for the DLA
metallicity, which does not allow to draw strong conclusions about the nature
of those systems or about their role in ``cosmic chemical evolution''.

</DOC>
<DOC>
<DOCNO> 152154 </DOCNO>
Thermodynamic Properties of a Quantum Group Boson Gas $GL_{p,q}(2)$


  An approach is proposed enabling to effectively describe the behaviour of a
bosonic system. The approach uses the quantum group $GL_{p,q}(2)$ formalism. In
effect, considering a bosonic Hamiltonian in terms of the $GL_{p,q}(2)$
generators, it is shown that its thermodynamic properties are connected to
deformation parameters $p$ and $q$. For instance, the average number of
particles and the pressure have been computed. If $p$ is fixed to be the same
value for $q$, our approach coincides perfectly with some results developed
recently in this subject. The ordinary results, of the present system, can be
found when we take the limit $p=q=1$.

</DOC>
<DOC>
<DOCNO> 72052 </DOCNO>
Elliptic flow at SPS and RHIC: from kinetic transport to hydrodynamics


  Anisotropic transverse flow is studied in Pb+Pb and Au+Au collisions at SPS
and RHIC energies. The centrality and transverse momentum dependence at
midrapidity of the elliptic flow coefficient v_2 is calculated in the
hydrodynamic and low density limits. Hydrodynamics is found to agree well with
the RHIC data for semicentral collisions up to transverse momenta of 1-1.5
GeV/c, but it considerably overestimates the measured elliptic flow at SPS
energies. The low density limit LDL is inconsistent with the measured magnitude
of v_2 at RHIC energies and with the shape of its p_t-dependence at both RHIC
and SPS energies. The success of the hydrodynamic model points to very rapid
thermalization in Au+Au collisions at RHIC and provides a serious challenge for
kinetic approaches based on classical scattering of on-shell particles.

</DOC>
<DOC>
<DOCNO> 169574 </DOCNO>
Antibunching effect of the radiation field in a microcavity with a


  The interaction between the radiation field in a microcavity with a mirror
undergoing damping oscillation is investigated. Under the heavily damping
cases, the mirror variables are adiabatically eliminated.
  The the stationary conditions of the system are discussed. The small
fluctuation approximation around steady values is applied to analysis the
antibunching effect of the cavity field. The antibunching condition is given
under two limit cases.

</DOC>
<DOC>
<DOCNO> 11316 </DOCNO>
Role of Orbital Degeneracy in Double Exchange Systems


  We investigate the role of orbital degeneracy in the double exchange (DE)
model. In the $J_{H}\to\infty$ limit, an effective generalized ``Hubbard''
model incorporating orbital pseudospin degrees of freedom is derived. The model
possesses an exact solution in one- and in infinite dimensions. In 1D, the
metallic phase off ``half-filling'' is a Luttinger liquid with
pseudospin-charge separation. Using the $d=\infty$ solution for our effective
model, we show how many experimental observations for the well-doped ($x\simeq
0.3$) three-dimensional manganites $La_{1-x}Sr_{x}MnO_{3}$ can be qualitatively
explained by invoking the role of orbital degeneracy in the DE model.

</DOC>
<DOC>
<DOCNO> 117524 </DOCNO>
Regular magnetic fields in the dwarf irregular galaxy NGC 4449


  We present a high-resolution VLA study of the total power and polarized radio
continuum emission at 8.46 and 4.86 GHz of the irregular galaxy NGC 4449, known
for its weak rotation and non-systematic gas motions. We found strong
galaxy-scale regular magnetic fields, which is surprising because of a lack of
ordered rotation required for the dynamo action. The strength of the regular
field reaches 8 $\mu$G and that of the total field 14 $\mu$G, comparable to
that of the total magnetic field strength in radio-bright spirals. The magnetic
vectors in NGC 4449 form radial ``fans'' in the central region and fragments of
a spiral pattern in the galaxy's outskirts. These structures are associated
with large regions of systematic Faraday rotation, implying genuine
galaxy-scale magnetic fields rather than random ones compressed and stretched
by gas flows. The observed pattern of polarization B-vectors is similar to
dynamo-type fields in normal spirals. Nonstandard, fast dynamo concepts are
required to explain the observed field strengths, though it is unknown what
kind of magnetic field geometry can be produced in slowly and chaotically
rotating objects. The so far neglected role of magnetic fields for the dynamics
and star formation in dwarf irregulars also needs to be revised.

</DOC>
<DOC>
<DOCNO> 101774 </DOCNO>
Generators of the cohomology ring of moduli spaces of sheaves on


  Let M be a moduli space of stable sheaves on a K3 or Abelian surface S. We
express the class of the diagonal in the cartesian square of M in terms of the
Chern classes of a universal sheaf. Consequently, we obtain generators of the
cohomology ring of M. When S is a K3 and M is the Hilbert scheme of length n
subschemes, this set of generators is sufficiently small in the sense that
there aren't any relations among them in the stable cohomology ring.
  When S is the cotangent bundle of a Riemann surface, we recover the result of
T. Hausel and M. Thaddeus: The cohomology ring of the moduli spaces of Higgs
bundles is generated by the universal classes.

</DOC>
<DOC>
<DOCNO> 84470 </DOCNO>
Geometric Interpretation of Schwarzschild Instantons


  In this note we address the problem of finding Abelian instantons of finite
energy on the Euclidean Schwarzschild manifold. This amounts to construct
self-dual L^2 harmonic 2-forms on the space. Gibbons found a non-topological
L^2 harmonic form in the Taub-NUT metric, leading to Abelian instantons with
continuous energy. We imitate his construction in the case of the Euclidean
Schwarzschild manifold and find a non-topological self-dual L^2 harmonic 2-form
on it. We show how this gives rise to Abelian instantons and identify them with
SU(2)-instantons of Pontryagin number 2n^2 found by Charap and Duff in 1977.
Using results of Dodziuk and Hitchin we also calculate the full L^2 harmonic
space for the Euclidean Schwarzschild manifold.

</DOC>
<DOC>
<DOCNO> 121885 </DOCNO>
The Optical Gravitational Lensing Experiment. Multiple Cluster


  We present 100 multiple cluster candidates selected from the OGLE catalog of
star clusters in the Large Magellanic Cloud. Statistical analysis shows that
the significant fraction of these objects may constitute physical systems.
Coeval ages of 102 components of multiple objects suggest their common origin.
53 components have very different ages. The comparison of the population of
multiple clusters candidates from the SMC and the LMC shows that: a)
distributions of sizes and ages of multiple and single clusters from the
Magellanic Clouds are very similar, b) the difference of sizes of components of
a given system is small, c) in both distributions of separation of multiple
clusters from the LMC and SMC two peaks are seen at about 9 pc and 15 pc, d)
both age distributions reveal peaks around 100 Myr, which may be connected with
the last encounter of the LMC and the SMC.

</DOC>
<DOC>
<DOCNO> 10914 </DOCNO>
Thermal relaxation in charge ordered Pr$_{0.63}$ Ca$_{0.37}$ MnO$_3$ in


  We report observation of substantial thermal relaxation in single crystal of
charge ordered system Pr$_{0.63}$Ca$_{0.37}$MnO$_3$ in an applied magnetic
field of H = 8T. The relaxation is observed when the temperature is scanned in
presence of a magnetic field in the temperature interval $T_{MH}<T<T_{CO}$
where $T_{CO}$ is the charge ordering temperature and $T_{MH}$ is charge
melting temperature in a field. In this temperature range the system has
coexisting charged ordered insulator (COI) and ferromagnetic metallic (FMM)
phases. No such relaxation is observed in the COI state in H = 0T or in the FMM
phase at $T < T_{MH}$ in presence of a magnetic field. We conclude that the
thermal relaxation is due to two coexisting phases with nearly same free
energies but separated by a potential barrier. This barrier makes the
transformation from one phase to the other time-dependent in the scale of the
specific heat experiment and gives rise to the thermal relaxation.

</DOC>
<DOC>
<DOCNO> 80934 </DOCNO>
Calculation of $K\to \pi$ matrix elements in quenched domain-wall QCD


  We explore the possibility for an evaluation of non-leptonic $\Delta S=1$ $K$
decay amplitudes through the calculation of $K\to\pi$ matrix elements using
domain-wall QCD. The relation between the physical $K\to\pi\pi$ matrix elements
and $K\to\pi$ matrix elements deduced from chiral perturbation theory is
recapitulated. Quenched numerical simulations are performed on an $16^3\times
32\times 16$ lattice at a lattice spacing $a^{-1}\approx 2$GeV for both the
standard plaquette gauge action and a renormalization-group improved gauge
action, and reasonable signals for $K\to\pi$ matrix elements are obtained.
Preliminary results are reported on the $K\to\pi\pi$ matrix elements, and
results from two actions are compared.

</DOC>
<DOC>
<DOCNO> 117112 </DOCNO>
The Energy of the Universe, the Scaling-Dependent Coupling Constant


  From the hypothesis of a quadratic dependence of the binding energy of the
quarks on the length scale and from the idea of a universal running coupling
constant, we get the closure mass of the Universe and the pion mass. Besides
this, we propose a free energy for the pions which stationarity condition leads
to a closed form for the pion mass as a function of the Planck mass and of the
Hubble constant.

</DOC>
<DOC>
<DOCNO> 72037 </DOCNO>
Precise calculation of neutralino relic density in the minimal


  We study precise calculation of neutralino relic density in the minimal
supergravity model. We compare the exact formula for the thermal average of the
neutralino annihilation cross section times relative velocity with the
expansion formula in terms of the temperature, including all the contributions
to neutralino annihilation cross section analytically. We confirm that the
expansion formula fails badly near s-channel poles. We show that the expansion
method causes 5-10 % error even far away from the poles.

</DOC>
<DOC>
<DOCNO> 118228 </DOCNO>
Analysis of cosmic ray data


  Reviews statistical methods for 1- and 2-dimensional analysis of cosmic ray
data including recent Bayesian analyses.

</DOC>
<DOC>
<DOCNO> 8752 </DOCNO>
Error-correcting codes and image restoration with multiple stages of


  We consider the problems of error-correcting codes and image restoration with
multiple stages of dynamics. Information extracted from the former stage can be
used selectively to improve the performance of the latter one. Analytic results
were derived for the mean-field systems using the cavity method. We find that
it has the advantage of being tolerant to uncertainties in hyperparameter
estimation, as confirmed by simulations.

</DOC>
<DOC>
<DOCNO> 122953 </DOCNO>
A Search for the Damped Ly-alpha Absorber at z=1.86 toward QSO 1244+3443


  We have carried out a high-resolution imaging search for the galaxy
associated with the damped Lyman-alpha (DLA) absorber at z=1.859 toward the
z_{em}=2.48 quasar QSO 1244+3443, using the HST and the NICMOS. Images were
obtained in the broad filter F160W and the narrow filter F187N with camera 2 on
NICMOS with the goal of detecting the rest-frame optical continuum and the
H-alpha line emission from the DLA. After PSF subtraction, two weak features
are seen at projected separations of 0.16-0.24" from the quasar. Parts of these
features may be associated with the DLA absorber, although we cannot completely
rule out that they could be artifacts of the point spread function (PSF). If
associated with the DLA, the objects would be ~1-2 h_{70}^{-1} kpc in size with
integrated flux densities of 2.5 and 3.3 mu Jy in the F160W filter, implying
luminosities at lambda_{central}=5600 A in the DLA rest frame of 4.4-5.9 x
10^{9} h_{70}^{-2} L_{solar} at z=1.86, for q0=0.5. However, no significant
H-alpha line emission is seen from these objects, suggesting low star formation
rates (SFRs). Our 3 sigma upper limit on the SFR in the DLA is 1.3 h_{70}^{-2}
M_{solar}/yr for q0 = 0.5 (2.4 h_{70}^{-2} M_{solar} yr^{-1} for q0 = 0.1).
This together with our earlier result for LBQS 1210+1731 mark a significant
improvement over previous constraints on the star formation rates of DLAs. A
combination of low SFR and some dust extinction is likely to be responsible for
the lack of H-alpha emission. Alternatively, the objects, may be associated
with the quasar host galaxy. In any case, our observations suggest that the DLA
is not a large bright proto-disk, but a compact object or a low-surface
brightness galaxy. If the two features are PSF artifacts then the constraints
on DLA properties are even more severe.

</DOC>
<DOC>
<DOCNO> 121431 </DOCNO>
Exploring Galaxy Evolution from Infrared Number Counts and Cosmic


  Recently reported infrared (IR) galaxy number counts and cosmic infrared
background (CIRB) all suggest that galaxies have experienced a strong evolution
sometime in their lifetime. We statistically estimate the galaxy evolution
history from these data. We find that an order of magnitude increase of the
far-infrared (FIR) luminosity at redshift z = 0.5 - 1.0 is necessary to
reproduce the very high CIRB intensity at 140 um reported by Hauser et al.
(1998). z \sim 0.75 and decreases to, even at most, a factor of 10 toward z
\sim 5, though many variants are allowed within these constraints. This
evolution history also satisfies the constraints from the galaxy number counts
obtained by IRAS, ISO and, roughly, SCUBA. The rapid evolution of the comoving
IR luminosity density required from the CIRB well reproduces the very steep
slope of galaxy number counts obtained by ISO. We also estimate the cosmic star
formation history (SFH) from the obtained FIR luminosity density, considering
the effect of the metal enrichment in galaxies. The derived SFH increases
steeply with redshift in 0 < z < 0.75, and becomes flat or even declines at z >
0.75. This is consistent with the SFH estimated from the reported ultraviolet
luminosity density. In addition, we present the performance of the Japanese
ASTRO-F FIR galaxy survey. We show the expected number counts in the survey. We
also evaluate how large a sky area is necessary to derive a secure information
of galaxy evolution up to z \sim 1 from the survey, and find that at least 50 -
300 deg^2 is required.

</DOC>
<DOC>
<DOCNO> 10831 </DOCNO>
Ground state of two unlike charged colloids: An analogy with ionic


  In this letter, we study the ground state of two spherical macroions of
identical radius, but asymmetric bare charge ((Q_{A}>Q_{B})). Electroneutrality
of the system is insured by the presence of the surrounding divalent
counterions. Using Molecular Dynamics simulations within the framework of the
primitive model, we show that the ground state of such a system consists of an
overcharged and an undercharged colloid. For a given macroion separation the
stability of these ionized-like states is a function of the difference
((\sqrt{N_{A}}-\sqrt{N_{B}})) of neutralizing counterions (N_{A}) and (N_{B}).
Furthermore the degree of ionization, or equivalently, the degree of
overcharging, is also governed by the distance separation of the macroions. The
natural analogy with ionic bonding is briefly discussed.

</DOC>
<DOC>
<DOCNO> 100821 </DOCNO>
Matching, linear systems, and the ball and beam


  A recent approach to the control of underactuated systems is to look for
control laws which will induce some specified structure on the closed loop
system. This basic idea is used in several papers already. In this paper, we
will describe one matching condition and an approach for finding all control
laws that fit the condition. After an analysis of the resulting control laws
for linear systems, we will present the results from an experiment on a ball
and beam system.

</DOC>
<DOC>
<DOCNO> 39652 </DOCNO>
New particle searches


  This review presents recent results on new particle searches achieved at
Tevatron, Hera and LEP. After a brief outline of the searches on exotic
particles, results on supersymmetric particles and Higgs bosons are detailed.
Near future prospects are also given.

</DOC>
<DOC>
<DOCNO> 100380 </DOCNO>
On the Complete Solution to the Most General Fifth Degree Polynomial


  The motivation behind this note, is due to the non success in finding the
complete solution to the General Quintic Equation. The hope was to have a
solution with all the parameters precisely calculated in a straight forward
manner. This paper gives the closed form solution for the five roots of the
General Quintic Equation. They can be generated on Maple V, or on the new
version Maple VI. On the new version of maple, Maple VI, it may be possible to
insert all the substitutions calculated in this paper, into one another, and
construct one large equation for the Tschirnhausian Transformation. The
solution also uses the Generalized Hypergeometric Function which Maple V can
calculate, robustly.

</DOC>
<DOC>
<DOCNO> 117367 </DOCNO>
Eccentric Stellar Discs with Strong Density Cusps and Separable


  We introduce a class of eccentric discs with "strong" density cusps whose
potentials are of St\"ackel form in elliptic coordinates. Our models exhibit
some striking features: sufficiently close to the location of the cusp, the
potential and surface density distribution diverge as $\Phi \propto r^{-1}$ and
$\Sigma \propto r^{-2}$, respectively. As we move outward from the centre, the
model takes a non-axisymmetric, lopsided structure. In the limit, when $r$
tends to infinity, the isocontours of $\Phi$ and $\Sigma$ become spherically
symmetric. It is shown that the configuration space is occupied by three
families of regular orbits: {\it eccentric butterfly}, {\it aligned loop} and
{\it horseshoe} orbits. These orbits are properly aligned with the surface
density distribution and can be used to construct self-consistent equilibrium
states.

</DOC>
<DOC>
<DOCNO> 69421 </DOCNO>
Large Extra Dimensions in Rare Decays


  The prospect of experimental verification of the large extra dimension
scenario in rare decays is discussed. The case of J/\Psi and \Upsilon to photon
+ missing energy is calculated in detail, and it is shown that the limit on the
compactification scale M_S lies at present in the ten GeV range. In contrast to
the quarkonium systems, signals in Kaon and Pion decays will be small.

</DOC>
<DOC>
<DOCNO> 71679 </DOCNO>
Effective Dual Higgs Model with a Dipole-Type Field


  The dual Higgs model is reformulated in terms of two-point Wightman functions
with the equations of motion involving higher derivatives. In the system of the
test color charges an analytic expression for the string tension is derived.

</DOC>
<DOC>
<DOCNO> 101878 </DOCNO>
Deformation complex of a d-algebra is a (d+1)-algebra


  We prove thst the deformation complex of a d-algebra (shifted by 1-d) carries
a natural structure of (d+1)-algebra. This is a purely algebraic version of a
similkar theorem of Kontsevich.

</DOC>
<DOC>
<DOCNO> 99502 </DOCNO>
String Partition Functions and Infinite Products


  We continue to explore the conjectural expressions of the Gromov-Witten
potentials for a class of elliptically and K3 fibered Calabi-Yau 3-folds in the
limit where the base P^1 of the K3 fibration becomes infinitely large. At least
in this limit we argue that the string partition function (=the exponential
generating function of the Gromov-Witten potentials) can be expressed as an
infinite product in which the Kahler moduli and the string coupling are treated
somewhat on an equal footing. Technically speaking, we use the exponential
lifting of a weight zero Jacobi form to reach the infinite product as in the
celebrated work of Borcherds. However, the relevant Jacobi form is associated
with a lattice of Lorentzian signature. A major part of this work is devoted to
an attempt to interpret the infinite product or more precisely the Jacobi form
in terms of the bound states of D2- and D0-branes using a vortex description
and its suitable generalization.

</DOC>
<DOC>
<DOCNO> 178862 </DOCNO>
Hadron Structure Studied with the Electromagnetic Probe - from Giant


  The development of theoretical photonuclear physics over the last 40 years is
illustrated by a few selected examples highlighting a number of important
issues like collective motion in nuclei, the role of subnuclear degrees of
freedom, relativity and meson production.

</DOC>
<DOC>
<DOCNO> 70149 </DOCNO>
Backreaction and the Parametric Resonance of Cosmological Fluctuations


  We study the class of two-field inflationary Universe models \lambda\phi^4/4
+ g^2\chi^2\phi^2/2, in which parametric resonance during the initial stages of
reheating can lead to an exponential amplification of the amplitude of
cosmological fluctuations. Employing both analytical arguments and numerical
simulations, we determine the time at which backreaction of fluctuations on the
background fields shuts off the exponential growth, making use of the Hartree
approximation, and including scalar metric perturbations. For the case
g^2/\lambda=2, we find that the amplitude of fluctuations after preheating will
exceed the observational upper bound independent of the value of \lambda,
unless the duration of inflation is very long. Cosmological fluctuations are
acceptably small for g^2/\lambda>=8. We also find that the addition of
\chi-field self-interaction can limit the growth of fluctuations, and in the
negative-coupling case the system can become effectively single-field, removing
the resonance.

</DOC>
<DOC>
<DOCNO> 100716 </DOCNO>
Eta-invariant and Pontrjagin duality in K-theory


  The topological significance of the spectral Atiyah-Patodi-Singer
eta-invariant is investigated under the parity conditions of P. Gilkey. We show
that twice the fractional part of the invariant is computed by the linking
pairing in K-theory with the orientation bundle of the manifold. The Pontrjagin
duality implies the nondegeneracy of the linking form. An example of a
nontrivial fractional part for an even-order operator is presented. This result
answers the question of P. Gilkey (1989) concerning the existence of even-order
operators on odd-dimensional manifolds with nontrivial fractional part of
eta-invariant.

</DOC>
<DOC>
<DOCNO> 118193 </DOCNO>
Search and Discovery Tools for Astronomical On-line Resources and


  A growing number of astronomical resources and data or information services
are made available through the Internet. However valuable information is
frequently hidden in a deluge of non-pertinent or non up-to-date documents. At
a first level, compilations of astronomical resources provide help for
selecting relevant sites. Combining yellow-page services and meta-databases of
active pointers may be an efficient solution to the data retrieval problem.
Responses generated by submission of queries to a set of heterogeneous
resources are difficult to merge or cross-match, because different data
providers generally use different data formats: new endeavors are under way to
tackle this problem. We review the technical challenges involved in trying to
provide general search and discovery tools, and to integrate them through upper
level interfaces.

</DOC>
<DOC>
<DOCNO> 11462 </DOCNO>
Direct Observation of the Quantum Energy Gap in S = 1/2 Tetragonal


  Using an electron spin resonance spectrometer covering a wide range of
frequency and magnetic field, we have measured the low energy excitations of
the S=1/2 tetragonal antiferromagnets, Sr_{2}CuO_{2}Cl_{2} and
Sr_{2}Cu_{3}O_{4}Cl_{2}. Our observation of in-plane energy gaps of order 0.1
meV at zero external magnetic field are consistent with a spin wave
calculation, which includes several kinds of quantum fluctuations that remove
frustration. Results agree with other experiments and with exchange anisotropy
parameters determined from a five band Hubbard model.

</DOC>
<DOC>
<DOCNO> 12479 </DOCNO>
Characterization of long-chain branching effects in linear rheology


  This is the last part of a series of five articles published in Journal of
Rheology (Maier et al. (1998), Thimm et al. (1999a), Thimm et al. (2000a),
Thimm et al. (2000c)) in which progress on the determination of binary
molecular weight distributions from rheological data has been reported. In this
article is discussed in how far the developed methods can also be used to
characterize long-chain branching effects.
  Monomodal samples which contain long-chain branches will show two relaxation
processes in the rheological examination, which are converted to two peaks in a
corresponding molecular weight distribution. But these samples will show only
one peak in a molecular weight distribution determined by a size-exclusion
chromatography examination. This difference can be used to characterize
long-chain branched materials as will be explained in this article.
  The usefulness of this method is demonstrated by examining polymers, which
contain definite long-chain branches specified from the way, they were made.

</DOC>
<DOC>
<DOCNO> 99635 </DOCNO>
A vertical exterior derivative in multisymplectic geometry and a graded


  A vertical exterior derivative is constructed that is needed for a graded
Poisson structure on multisymplectic manifolds over nontrivial vector bundles.
In addition, the properties of the Poisson bracket are proved and first
examples are discussed.

</DOC>
<DOC>
<DOCNO> 151454 </DOCNO>
Supergravity description of field theories on curved manifolds and a no


  In the first part of this paper we find supergravity solutions corresponding
to branes on worldvolumes of the form $R^d \times \Sigma$ where $\Sigma$ is a
Riemann surface. These theories arise when we wrap branes on holomorphic
Riemann surfaces inside $K3$ or CY manifolds. In some cases the theory at low
energies is a conformal field theory with two less dimensions. We find some
non-singular supersymmetric compactifications of M-theory down to $AdS_5$. We
also propose a criterion for permissible singularities in supergravity
solutions.
 In the second part of this paper, which can be read independently of the
first, we show that there are no non-singular Randall-Sundrum or de-Sitter
compactifications for large class of gravity theories.

</DOC>
<DOC>
<DOCNO> 67768 </DOCNO>
The Strange Quark Problem in the Framework of Statistical Distributions


  A large class of polarized and unpolarized deep inelastic data is
successfully described with Fermi-Dirac functions for the non-diffractive part
of quark parton distributions. The NLO approach used here improves the
agreement with experiment of the previous LO work. We get a broader
distribution for the strange parton s(x) than for sbar(x).

</DOC>
<DOC>
<DOCNO> 99513 </DOCNO>
Location of incenters and Fermat points in variable triangles


  The orthocentroidal circle of a nonequilateral triangle has diameter GH,
joining the centroid to the orthocenter. We show that the incenters of
triangles with a given Euler line simply cover the interior of the
orthocentroidal circle, and that their Fermat points also lie within this
circle.

</DOC>
<DOC>
<DOCNO> 9404 </DOCNO>
Influence of Induced Interactions on the Superfluid Transition in Dilute


  We calculate the effects of induced interactions on the transition
temperature to the BCS state in dilute Fermi gases. For a pure Fermi system
with 2 species having equal densities, the transition temperature is suppressed
by a factor $(4e)^{1/3}\approx 2.2$, and for $\nu$ fermion species, the
transition temperature is increased by a factor $(4e)^{\nu /3-1} \approx
2.2^{\nu-3}$. For mixtures of fermions and bosons the exchange of boson density
fluctuations gives rise to an effective interaction, and we estimate the
increase of the transition temperature due to this effect.

</DOC>
<DOC>
<DOCNO> 84505 </DOCNO>
Quintessence and Gravitational Waves


  We investigate some aspects of quintessence models with a non-minimally
coupled scalar field and in particular we show that it can behave as a
component of matter with $-3 \lesssim P/\rho \lesssim 0$. We study the
properties of gravitational waves in this class of models and discuss their
energy spectrum and the cosmic microwave background anisotropies they induce.
We also show that gravitational waves are damped by the anisotropic stress of
the radiation and that their energy spectrum may help to distinguish between
inverse power law potential and supergravity motivated potential. We finish by
a discussion on the constraints arising from their density parameter
$\Omega_\GW$.

</DOC>
<DOC>
<DOCNO> 119352 </DOCNO>
Low and High Ionization Absorption Properties of Mg II


  We present extensive metal-line absorption properties for 45 absorption
systems that were selected by their Mg II absorption at redshifts between 0.4
and 1.4. For each system the properties of several chemical species are
determined, including a wide range of ionization conditions. In the optical,
the absorption systems have been observed at ~6 km/s resolution with
HIRES/Keck, which covered Mg II, several Fe II transitions, Mg I, and in some
cases (depending upon redshift), Ca II, Ti II, Mn II, and Al III. Ultraviolet,
lower resolution (~230 km/s) Faint Object Spectrograph data (1600 - 3275 Ang)
were obtained from the Hubble Space Telescope archive. These spectra covered Al
II, Al III, Si II, Si III, Si IV, C II, C III, C IV, N V, O VI, and several
Lyman series transitions, with coverage dependent upon the absorption system
redshift. From these data, we infer that Mg II absorbing galaxies at
intermediate redshifts have multiphase gaseous structures.

</DOC>
<DOC>
<DOCNO> 152319 </DOCNO>
On Realising N=1 Super Yang-Mills in M theory


  Pure N=1 super Yang-Mills theory can be realised as a certain low energy
limit of M theory near certain singularities in $G_2$-holonomy spaces. For
SU(n) and SO(2n) gauge groups these $M$ theory backgrounds can be regarded as
strong coupling limits of wrapped D6-brane configurations in Type IIA theory on
certain non-compact Calabi-Yau spaces such as the deformed conifold. Various
aspects of such realisations are studied including the generation of the
superpotential, domain walls, QCD strings and the relation to recent work of
Vafa. In the spirit of this recent work we propose a `gravity dual' of M theory
near these singularities.

</DOC>
<DOC>
<DOCNO> 8295 </DOCNO>
Soft Mode Anomalies in the Perovskite Relaxor Pb(Mg1/3Nb2/3)O3


  Neutron inelastic scattering measurements of the polar TO phonon mode in the
cubic relaxor Pb(Mg1/3Nb2/3)O3, at room temperature, reveal anomalous behavior
similar to that recently observed in the Pb(Zn1/3Nb2/3)_{0.92}Ti_{0.08}O3
system in which the optic branch appears to drop precipitously into the
acoustic branch at a finite value of the momentum transfer q = 0.20
1/Angstroms, measured from the zone center. By contrast, a recent neutron study
showed that PMN exhibits a normal TO phonon dispersion at 800 K. We speculate
this behavior is common to all relaxor materials and is the result of the
presence of nanometer-scale polarized domains in the crystal that form below a
temperature Td, which effectively prevent the propagation of long wavelength (q
= 0) phonons.

</DOC>
<DOC>
<DOCNO> 120842 </DOCNO>
Cosmic Shear with the VLT


  We report on the detection of cosmic shear on angular scales of 1.3-6.5
arcmin using 45 independent empty fields observed with the Very Large Telescope
(VLT). This result confirms previous measurements obtained with the CFH
Telescope at the same angular scales. We present the data analysis and the
first preliminary results.

</DOC>
<DOC>
<DOCNO> 8941 </DOCNO>
Description of Dynamic Properties of Finite Electron Systems in Density


  The self consistent version of the density functional theory (DFT) is
presented, which allows to calculate the ground state and dynamic properties of
finite multi-electron systems such as atoms, molecules and clusters. The exact
functional equation for the effective interaction, using which one can
construct the action functional, density functional, the response functions,
and excitation spectra of the considered systems, are discussed. We have also
related the eigenvalues of the single-particle Kohn-Sham equations to the real
single-particle spectra. We begin with the standard action functional and show
that it is useful in calculating the linear response functions via which all
physical characteristics of a many-body system can be expressed. It is shown,
that function can be causal (retarded), noncausal and advanced ones. This
resolves the well known paradox related to the causality and symmetry
properties of the response functions and the effective interaction.

</DOC>
<DOC>
<DOCNO> 11393 </DOCNO>
Rolling up of graphite sheet: Energetics of shell formation


  The energetics of transformation of a planar fragment of a graphite monolayer
into a spherical cluster is studied. The path considered is that a flat cluster
rolls up into a segment of a spherical shell. The energy landscape of the
process is presented. A simple model, formerly invented for calculating the
carbon nanocluster formation energy, is used to evaluate the energies of
intermediate states. Although the spherical-shell closed cluster has the lowest
energy, curving of a plane fragment into a segment has an energy barrier. The
barrier height goes to zero for clusters with the number of atoms greater than
some $N_{\rm th}$, for which the cluster size is found analytically.

</DOC>
<DOC>
<DOCNO> 122699 </DOCNO>
Angular separations of the lensed QSO images


  We have analyzed the observed image separations of the gravitationally lensed
images of QSOs for a possible correlation with the source redshift. Contrary to
the previously noted anti-correlation based on a smaller data set, no
correlation is found for the currently available data. We have calculated the
average image separations of the lensed QSOs as a function of source redshifts,
for isothermal spheres with cores in a flat universe, taking into account the
amplification bias caused by lensing. The shape of the distribution of average
image separation as a function of redshift is very robust and is insensitive to
most model parameters. Observations are found to be roughly consistent with the
theoretical results for models which assume the lens distribution to be (i)
Schechter luminosity function which, however, can not produce images with large
separation and (ii) the mass condensations in a cold dark matter universe, as
given by the Press-Schechter theory if an upper limit of 1-7$\times 10^{13}$
M$\odot$ is assumed on the mass of the condensations.

</DOC>
<DOC>
<DOCNO> 101235 </DOCNO>
Moyal Deformation, Seiberg-Witten-Map, and Integrable Models


  A covariant formalism for Moyal deformations of gauge theory and differential
equations which determine Seiberg-Witten maps is presented. Replacing the
ordinary product of functions by the noncommutative Moyal product,
noncommutative versions of integrable models can be constructed. We explore how
a Seiberg-Witten map acts in such a framework. As a specific example, we
consider a noncommutative extension of the principal chiral model.

</DOC>
<DOC>
<DOCNO> 122996 </DOCNO>
A Far-Ultraviolet Spectroscopic Survey of the Globular Cluster 47 Tuc


  We present preliminary results from a FUV spectroscopic and photometric
survey of the globular cluster 47 Tuc. Our main goal is to either confirm or
rule out the existence of a large population of CVs in the core of this
cluster.
  We have so far identified approximately 425 FUV sources, most of which are
probably hot, young WDs. However, we have also found approximately 30 FUV
sources whose position in a FUV-optical color-magnitude diagram makes them
strong CV candidates. If most or all of these objects are eventually confirmed
as CVs, the large CV population predicted by tidal capture theory has finally
been found.
  Our data has also allowed us to resolve the long-standing puzzle surrounding
AKO 9, a UV-bright and highly variable 1.1 day binary system in 47 Tuc. AKO 9
is the brightest FUV source in our data and presents a blue FUV spectrum with
strong CIV and HeII emission lines. Its spectrum is similar to that of the
long-period, DN-type field CV GK Per. Based on this similarity and other
evidence, we suggest that AKO 9 is a long-period CV in which mass-transfer is
driven by the nuclear evolution of a sub-giant donor star.

</DOC>
<DOC>
<DOCNO> 68939 </DOCNO>
A Covariant Generalization of the Real-Time Green's Functions Method in


  A generalized quantum kinetic equation (RKE) of the Kadanoff-Baym type is
obtained on the basis of the Heisenberg equations of motion where the time
evolution and space translation are separated from each other by means of the
covariant method. The same approach is used also for a covariant modification
of the real-time Green's functions method based on the Wigner representation.
The suggested approach does not contain arbitrariness' elements and
uncertainties which often arise from derivation of RKE on the basis of the
motion equations of the Kadanoff-Baym type for the correlation functions in the
case of systems with inner degrees of freedom. Possibilities of the proposed
method are demonstrated by examples of derivation of RKE of the Vlasov type and
collision integrals of the Boltzmann-Uehling-Uhlenbeck (BUU) type in the frame
of the $\sigma \omega$ -version of quantum hadrodynamics, for the simplest case
of spin saturated nuclear matter without antinuclear component. Here, the
quasiparticle approximation in a covariant performance is used. A
generalization of the method for the description of strong non-equilibrium
states based on the non-equilibrium statistical operator is then proposed as
well.

</DOC>
<DOC>
<DOCNO> 120773 </DOCNO>
Black hole to bulge mass correlation in Active Galactic Nuclei: A test


  A mass correlation of central black holes and their spheroids ~0.002(within a
factor of three) is suggested by Hubble Space Telescope (HST) and various
ground-based CCD photometries of early type galaxies. The near-IR images of
quasar hosts and the emission line measurements of Broad Line Region for bright
QSOs present a similar correlation, which supports the speculation of an
evolutionary linkage between the early active QSO phase and the central black
holes in normal galaxies. On the other hand, recent reverberation mapping of a
sample of Seyferts shows a broad distribution of black hole to bulge mass ratio
with a mean of ~10^{-3.5}, about one magnitude lower than the value in early
type galaxies and bright QSOs. Adopting a simple unified formation scheme for
QSOs and Seyferts, we will discuss in this letter the dependence of the black
hole to bulge mass ratio in Active Galactic Nuclei (AGNs) on the environmental
parameters of the host galaxies. We show a broad distribution of the mass
correlation could be due to different velocity dispersion of the accreting gas
from different formation mechanism, and the mass ratio in normal galaxies and
bright QSOs is probably a limit case of black hole evolution by merger enhanced
accretion close to Eddington limit.

</DOC>
<DOC>
<DOCNO> 10150 </DOCNO>
Comment on ``Magnetoresistance Anomalies in Antiferromagnetic


  In a recent Letter Ando et al (cond-mat/9905071) discovered an anomalous
magnetoresistance(MR) in hole doped antiferromagnetic YBa$_2$Cu$_3$O$_{6+x}$,
which they attributed to charged stripes, i.e., to segregation of holes into
lines. In this Comment we show that the experiments, albeit being interesting,
do not prove the existence of stripes. In our view the anomalous behavior is
due to an (a,b) plane anisotropy of the resistivity in the bulk and to a
magnetic field dependent antiferromagnetic (AF) domain structure. It is
unlikely that domain walls are charged stripes.

</DOC>
<DOC>
<DOCNO> 151472 </DOCNO>
Star Operation in Quantum Mechanics


  We outline the description of Quantum Mechanics with noncommuting coordinates
within the framework of star operation. We discuss simple cases of
integrability.

</DOC>
<DOC>
<DOCNO> 67807 </DOCNO>
Diffractive Lambda_c^+ Productions in Polarized pp Reactions and


  To test the model of the polarized gluon distribution $\Delta G(x, Q^2)$ in
the proton, we propose a new process, diffractive $\Lambda_c^+$ productions in
polarized $pp$ reactions, which will be observed in the forthcoming RHIC and
also the proposed HERA-$\vec {\rm N}$ experiments. The spin correlation between
the target proton and the $\Lambda_c^+$ produced in the target fragmentation
region largely depends on $\Delta G(x, Q^2)$ and thus, the process is quite
promising for testing the models of $\Delta G(x, Q^2)$.

</DOC>
<DOC>
<DOCNO> 67838 </DOCNO>
Detecting a light Higgs boson at the Fermilab Tevatron through enhanced


  We analyze the prospects of the Tevatron for finding a Higgs boson in the two
photon decay mode. We conclude that the Standard Model (SM) Higgs boson will
likely not be discovered in this mode. However, we motivate several theories
beyond the SM, including the MSSM, that predict a Higgs boson with enhanced
branching fractions into photons, and calculate the luminosity needed to
discover a general Higgs boson at the Tevatron by a two-photon invariant mass
peak at large transverse momentum. We find that a high luminosity Tevatron will
play a significant role in discovering or constraining these theories.

</DOC>
<DOC>
<DOCNO> 70596 </DOCNO>
Conditions for deconfinement transition signals from compact star


  A phase diagram for compact stars in the angular velocity (Omega) - baryon
number (N) plane is obtained with a dividing line for quark core
configurations. Trajectories of compact star evolution in this diagram are
studied for different scenarios defined by the external torque acting on the
star due to radiation and/or mass accretion. They show a characteristic change
in the rotational kinematics when entering the quark core regime. As a model
independent signal for the existence of a deconfinement phase transition in
compact stars a population clustering of accreting low-mass X-ray binaries in
the Omega-N plane at the dividing line is suggested. We present the conditions
under which this signal appears most pronounced.

</DOC>
<DOC>
<DOCNO> 10436 </DOCNO>
Influence of defects on the critical behaviour at the \boldmath{105} K


  The depth dependence of the crystallographic parameters mosaicity, lattice
parameter variation and integrated reflectivity and of the critical scattering
above the 105 K structural phase transition of SrTiO$_3$ have been studied in
five different single crystals by means of high resolution triple-crystal
diffractometry using 100-120 keV synchrotron radiation. Depth-dependent
impedance measurements indicate that the presence of oxygen vacancies is not
responsible for the two-length scale phenomenon. It is found that the sharp
component occurs only in surface near regions of highly perfect single crystals
and is coupled to an exponential inrease of the crystallographic quantities.
The second length scale is absent at a surface where the strain fields are able
to relax by a macroscopic bending of the lattice planes. The sharp component is
also strongly suppressed in crystals of relatively large mosaicity. The
combination of long range strain fields in highly perfect samples and the
vicinity of the surface seem to be necessary conditions for the observation of
the sharp component. The critical exponents for the second length scale are in
satisfying agreement with scaling laws if the intensity of the critical
scattering is assumed to be proportional to the square of the Lorentzian
susceptibility and not, as usual in the current convention, to a
Lorentzian-squared susceptibility. The critical exponents of the broad
component are independent of the appearance of the sharp component.

</DOC>
<DOC>
<DOCNO> 70571 </DOCNO>
The GDH Sum Rule and Related Integrals


  The spin structure of the nucleon resonance region is analyzed on the basis
of our phenomenological model MAID. Predictions are given for the
Gerasimov-Drell-Hearn sum rule as well as generalized integrals over spin
structure functions. The dependence of these integrals on momentum transfer is
studied and rigorous relationships between various definitions of generalized
Gerasimov-Drell-Hearn integrals and spin polarizabilities are derived. These
results are compared to the predictions of chiral perturbation theory and
phenomenological models.

</DOC>
<DOC>
<DOCNO> 84648 </DOCNO>
The geometry of photon surfaces


  The photon sphere concept in Schwarzschild space-time is generalized to a
definition of a photon surface in an arbitrary space-time. A photon sphere is
then defined as an SO(3)xR-invariant photon surface in a static spherically
symmetric space-time. It is proved, subject to an energy condition, that a
black hole in any such space-time must be surrounded by a photon sphere.
Conversely, subject to an energy condition, any photon sphere must surround a
black hole, a naked singularity or more than a certain amount of matter. A
second order evolution equation is obtained for the area of an SO(3)-invariant
photon surface in a general non-static spherically symmetric space-time. Many
examples are provided.

</DOC>
<DOC>
<DOCNO> 12122 </DOCNO>
Rotational modes in molecular magnets with antiferromagnetic Heisenberg


  In an effort to understand the low temperature behavior of recently
synthesized molecular magnets we present numerical evidence for the existence
of a rotational band in systems of quantum spins interacting with
nearest-neighbor antiferromagnetic Heisenberg exchange. While this result has
previously been noted for ring arrays with an even number of spin sites, we
find that it also applies for rings with an odd number of sites as well as for
all of the polytope configurations we have investigated (tetrahedron, cube,
octahedron, icosahedron, triangular prism, and axially truncated icosahedron).
It is demonstrated how the rotational band levels can in many cases be
accurately predicted using the underlying sublattice structure of the spin
array. We illustrate how the characteristics of the rotational band can provide
valuable estimates for the low temperature magnetic susceptibility.

</DOC>
<DOC>
<DOCNO> 99593 </DOCNO>
An automorphic form related to cubic surfaces


  This is a note constructing a certain weight 4 automorphic form on the moduli
space of cubic surfaces, posted here because it is referred to in
math.AG/0002066

</DOC>
<DOC>
<DOCNO> 120867 </DOCNO>
Structured Mixed Phase is Favored in Neutron Stars


  We give a general thermodynamical argument showing that in neutron stars, the
Coulomb structured mixed phase is always favored for any first order phase
transition involving systems in equilibrium with baryon number and electric
charge as the two independent components. This finding is likely to have
important consequences for many neutron star properties, e.g., glitch
phenomena, transport and superfluid properties, r-mode instabilities, and the
braking index.

</DOC>
<DOC>
<DOCNO> 119940 </DOCNO>
Evolution of the probability distribution function of galaxies in


  We present a new analytic calculation for the redshift-space evolution of the
1-point galaxy Probability Distribution Function (PDF). The nonlinear evolution
of the matter density field is treated by second-order Eulerian perturbation
theory and transformed to the galaxy density field via a second-order local
biasing scheme. We then transform the galaxy density field to redshift space,
again to second order. Our method uses an exact statistical treatment based on
the Chapman-Kolmogorov equation to propagate the probability distribution of
the initial mass field to the final redshifted galaxy density field. We derive
the moment generating function of the PDF and use it to find a new, closed-form
expression for the skewness of the redshifted galaxy distribution. We show that
our formalism is general enough to allow a non-deterministic (or stochastic)
biasing prescription. We demonstrate the dependence of the redshift space PDF
on cosmological and biasing parameters. Our results are compared with existing
models for the PDF in redshift space and with the results of biased N-body
simulations. We find that our PDF accurately models the redshift space
evolution and the nonlinear biasing.

</DOC>
<DOC>
<DOCNO> 8347 </DOCNO>
Scaling Law and Aging Phenomena in the Random Energy Model


  We study the effect of temperature shift on aging phenomena in the Random
Energy Model (REM). From calculation on the correlation function and simulation
on the Zero-Field-Cooled magnetization, we find that the REM satisfies a
scaling relation even if temperature is shifted. Furthermore, this scaling
property naturally leads to results obtained in experiment and the droplet
theory.

</DOC>
<DOC>
<DOCNO> 40502 </DOCNO>
Charged Multiplicities in Z Decays into u, d, and s Quarks


  About 4.4 million hadronic decays of Z bosons, recorded by the OPAL detector
at LEP at a centre-of-mass energy of around sqrt(s) = 91.2 GeV, are used to
determine the mean charged particle multiplicities for the three light quark
flavours. Events from primary u, d, and s quarks are tagged by selecting
characteristic particles which carry a large fraction of the beam energy. The
charged particle multiplicities are measured in the hemispheres opposite to
these particles. An unfolding procedure is applied to obtain these
multiplicities for each primary light quark flavour. This yields <n_u> = 17.77
+- 0.51 +0.86 -1.20,
  <n_d> = 21.44 +- 0.63 +1.46 -1.17,
  <n_s> = 20.02 +- 0.13 +0.39 -0.37, where statistical and systematic errors
are given. The results for <n_u> and <n_d> are almost fully statistically
anti-correlated. Within the errors the result is consistent with the flavour
independence of the strong interaction for the particle multiplicities in
events from the light up, down, and strange quarks.

</DOC>
<DOC>
<DOCNO> 11167 </DOCNO>
Coulomb Drag in Coherent Mesoscopic Systems


  We present a theory for Coulomb drag between two mesoscopic systems. Our
formalism expresses the drag in terms of scattering matrices and wave
functions, and its range of validity covers both ballistic and disordered
systems. The consequences can be worked out either by analytic means, such as
the random matrix theory, or by numerical simulations. We show that Coulomb
drag is sensitive to localized states, which usual transport measurements do
not probe. For chaotic 2D-systems we find a vanishing average drag, with a
nonzero variance. Disordered 1D-wires show a finite drag, with a large
variance, giving rise to a possible sign change of the induced current.

</DOC>
<DOC>
<DOCNO> 10450 </DOCNO>
Fourth Order Algorithms for Solving the Multivariable Langevin Equation


  We develop a fourth order simulation algorithm for solving the stochastic
Langevin equation. The method consists of identifying solvable operators in the
Fokker-Planck equation, factorizing the evolution operator for small time steps
to fourth order and implementing the factorization process numerically. A key
contribution of this work is to show how certain double commutators in the
factorization process can be simulated in practice. The method is general,
applicable to the multivariable case, and systematic, with known procedures for
doing fourth order factorizations. The fourth order convergence of the
resulting algorithm allowed very large time steps to be used. In simulating the
Brownian dynamics of 121 Yukawa particles in two dimensions, the converged
result of a first order algorithm can be obtained by using time steps 50 times
as large. To further demostrate the versatility of our method, we derive two
new classes of fourth order algorithms for solving the simpler Kramers equation
without requiring the derivative of the force. The convergence of many fourth
order algorithms for solving this equation are compared.

</DOC>
<DOC>
<DOCNO> 13483 </DOCNO>
Evidence for Surface Andreev Bound states in Cuprate Superconductors


  Tunneling and theoretical studies have suggested that Andreev bound states
form at certain surfaces of unconventional superconductors. Through studies of
the temperature and field dependence of the in-plane magnetic penetration depth
lambda_ab at low temperature, we have found strong evidence for the presence of
these states in clean single crystal YBCO and BSCCO. Crystals cut to expose a
[110] interface show a strong upturn in lambda_ab at around 7K, when the field
is oriented so that the supercurrents flow around this surface. In YBCO this
upturn is completely suppressed by a field of ~0.1 T.

</DOC>
<DOC>
<DOCNO> 84305 </DOCNO>
Macroscopic Einstein equations for a system of interacting particles and


  One of the possible applications of macroscopic Einstein equations has been
considered. So, the nonsingular isotropic and uniform cosmological model is
built. The cosmological consequences of this model are agree with conclusions
of standard hot model of the Universe.

</DOC>
<DOC>
<DOCNO> 100257 </DOCNO>
About the uniqueness and the denominators of the Kontsevich Integral


  We refine a Le and Murakami uniqueness theorem for the Kontsevich Integral in
order to specify the relationship between the two (possibly equal) main
universal link invariants: the Kontsevich Integral and the perturbative
expression of the Chern-Simons theory. As a corollary, we prove that the
Altschuler and Freidel anomaly (that groups the Bott and Taubes anomalous
terms) is a combination of diagrams with two univalent vertices; and we
explicitly define the isomorphism of the space of Feynman diagrams which
transforms the Kontsevich Integral into the Poirier limit of the perturbative
expression of the Chern-Simons theory, as a function of the anomaly. We use
this corollary to improve the Le estimates on the denominators of the
Kontsevich Integral.

</DOC>
<DOC>
<DOCNO> 120411 </DOCNO>
The Parker Instability in a Thick Gaseous Disk II: Numerical Simulations


  We present 2D, ideal-MHD numerical simulations of the Parker instability in a
multi-component warm disk model. The calculations were done using two numerical
codes with different algorithms, TVD and ZEUS-3D. The outcome of the numerical
experiments performed with both codes is very similar, and confirms the results
of the linear analysis for the undular mode derived by Kim et al. (2000): the
most unstable wavelength is about 3 kpc and its growth timescale is between
30-50 Myr (the growth rate is sensitive to the position of the upper boundary
of the numerical grid). Thus, the time and length scales of this multicomponent
disk model are substantially larger than those derived for thin disk models. We
use three different types of perturbations, random, symmetric, and
antisymmetric, to trigger the instability. The antisymmetric mode is dominant,
and determines the minimum time for the onset of the nonlinear regime. The
instability generates dense condensations and the final peak column density
value in the antisymmetric case, as also derived by Kim et al. (2000), is about
a factor of 3 larger than its initial value. These wavelengths and density
enhancement factors indicate that the instability alone cannot be the main
formation mechanism of giant molecular clouds in the general interstellar
medium. The role of the instability in the formation of large-scale
corrugations along spiral arms is briefly discussed.

</DOC>
<DOC>
<DOCNO> 83296 </DOCNO>
Naive Bayes and Exemplar-Based approaches to Word Sense Disambiguation


  This paper describes an experimental comparison between two standard
supervised learning methods, namely Naive Bayes and Exemplar-based
classification, on the Word Sense Disambiguation (WSD) problem. The aim of the
work is twofold. Firstly, it attempts to contribute to clarify some confusing
information about the comparison between both methods appearing in the related
literature. In doing so, several directions have been explored, including:
testing several modifications of the basic learning algorithms and varying the
feature space. Secondly, an improvement of both algorithms is proposed, in
order to deal with large attribute sets. This modification, which basically
consists in using only the positive information appearing in the examples,
allows to improve greatly the efficiency of the methods, with no loss in
accuracy. The experiments have been performed on the largest sense-tagged
corpus available containing the most frequent and ambiguous English words.
Results show that the Exemplar-based approach to WSD is generally superior to
the Bayesian approach, especially when a specific metric for dealing with
symbolic attributes is used.

</DOC>
<DOC>
<DOCNO> 13579 </DOCNO>
Shot noise in superconducting junctions with weak link formed by


  A theory is developed to study shot noise in superconducting (SAS) and hybrid
(SAN) junctions with singly occupied Anderson impurity (A) as a weak link. The
zero-frequency DC component of the shot noise spectral density is calculated at
zero temperature as a function of the bias at different Coulomb repulsion
strengths U, and show a remarkable structure resulting from combination of
electron-electron interaction and Andreev reflections.

</DOC>
<DOC>
<DOCNO> 152120 </DOCNO>
RR charges of D2-branes in group manifold and Hanany-Witten effect


  By exploiting the correspondence between the Cardy boundary state in SU(2)
group manifold and the BPS D3-brane configuration in the full asymptotically
flat geometry of NS5-branes, we show that the Hanany-Witten effect in 10D
background is encoded in the Cardy boundary states. The two RR Page D0 charges
of the $n$-th spherical D2-brane due to the contraction to $e$ or ($-e$) is
interpreted, and attributed to the Hanany-Witten effect.

</DOC>
<DOC>
<DOCNO> 152254 </DOCNO>
Approximate Decoherence of Histories and 't Hooft's Deterministic


  This paper explores the possibility that an exactly decoherent set of
histories may be constructed from an approximately decoherent set by small
distortions of the operators characterizing the histories. In particular, for
the case of histories of positions and momenta, this is achieved by doubling
the set of operators and then finding, amongst this enlarged set, new position
and momentum operators which commute, so decohere exactly, and which are
``close'' to the original operators. The enlarged, exactly decoherent, theory
has the same classical dynamics as the original one, and coincides with the
so-called deterministic quantum theories of the type recently studied by 't
Hooft. These results suggest that the comparison of standard and deterministic
quantum theories may provide an alternative method of characterizing emergent
classicality. A side-product is the surprising result that histories of momenta
in the quantum Brownian motion model (for the free particle in the
high-temperature limit) are exactly decoherent.

</DOC>
<DOC>
<DOCNO> 40678 </DOCNO>
Dark Matter Implications for Linear Colliders


  The existence of dark matter is currently one of the strongest motivations
for physics beyond the standard model. Its implications for future colliders
are discussed. In the case of neutralino dark matter, cosmological bounds do
not provide useful upper limits on superpartner masses. However, in simple
models, cosmological considerations do imply that for supersymmetry to be
observable at a 500 GeV linear collider, some signature of supersymmetry must
appear before the LHC.

</DOC>
<DOC>
<DOCNO> 8397 </DOCNO>
Generalization properties of finite size polynomial Support Vector


  The learning properties of finite size polynomial Support Vector Machines are
analyzed in the case of realizable classification tasks. The normalization of
the high order features acts as a squeezing factor, introducing a strong
anisotropy in the patterns distribution in feature space. As a function of the
training set size, the corresponding generalization error presents a crossover,
more or less abrupt depending on the distribution's anisotropy and on the task
to be learned, between a fast-decreasing and a slowly decreasing regime. This
behaviour corresponds to the stepwise decrease found by Dietrich et al.[Phys.
Rev. Lett. 82 (1999) 2975-2978] in the thermodynamic limit. The theoretical
results are in excellent agreement with the numerical simulations.

</DOC>
<DOC>
<DOCNO> 118534 </DOCNO>
Primordial Lithium Abundance as a Stringent Constraint on the Baryonic


  We have refined the estimate of the primordial level of $^7$Li abundance to
an accuracy better than 10%, based on high-precision Li abundances for
metal-poor halo stars, and a recent model of post-BBN (Big Bang
Nucleosynthesis) chemical evolution that provides a quantitative explanation of
the detected gentle ascent of the Spite Plateau for stars with metallicities
[Fe/H]$ > -3$. Our maximum likelihood analysis obtains an estimate for the
primordial Li abundance of $A({\rm Li})_p=2.07^{+0.16}_{-0.04}$, after taking
into account possible systematic errors in the estimation of Li abundances,
with the exception of a still-controversial issue regarding stellar depletion.
The inferred value of $\eta$ (the baryon-to-photon number-density ratio in the
universe) based on this estimate is more consistent with that derived from the
set of reported ``low He'' + ``high D'' from extragalactic sites than that
derived from reported ``high He'' + ``low D'' measurements. Since, within
current models of stellar depletion processes, it is difficult to account for
the observed very small scatter of Li abundance in metal-poor stars, our
estimate of $A({\rm Li})_p$ should be taken as an independent constraint on the
baryonic mass density parameter in the universe, giving $\Omega_b
h^2=(0.64-1.4)\times 10^{-2}$ with $h=H_0/100$ km s$^{-1}$Mpc$^{-1}$.

</DOC>
<DOC>
<DOCNO> 71420 </DOCNO>
Tau lepton Michel parameters and new physics


  A complete discussion of the constraints on the Michel parameters and the
ambiguities of their interpretation is presented. Estimators of new physics,
optimized for a very wide class of hypotheses and models, are proposed.

</DOC>
<DOC>
<DOCNO> 67635 </DOCNO>
One-particle inclusive CP asymmetries


  One-particle inclusive CP asymmetries in the decays of the type B -> D(*) X
are considered in the framework of a QCD based method to calculate the rates
for one-particle inclusive decays.

</DOC>
<DOC>
<DOCNO> 151352 </DOCNO>
Non-Commutative Moduli Spaces, Dielectric Tori and T-duality


  We review and extend recent work on the application of the non-commutative
geometric framework to an interpretation of the moduli space of vacua of
certain deformations of N=4 super Yang-Mills theories. We present a simple
worldsheet calculation that reproduces the field theory results and sheds some
light on the dynamics of the D-brane bubbles. Different regions of moduli space
are associated with D5-branes of various topologies; singularities in the
moduli space are associated with topology change. T-duality on toroidal
topologies maps between mirror string realizations of the field theory.

</DOC>
<DOC>
<DOCNO> 121247 </DOCNO>
Reprocessed emission line profiles from dense clouds in geometrically


  The central engines of active galactic nuclei (AGN) contain cold, dense
material as well as hot X-ray emitting gas. The standard paradigm for the
engine geometry is a cold thin disc sandwiched between hot X-ray coronae.
Strong support for this geometry in Seyferts comes from the study of
fluorescent iron line profiles, although the evidence is not ubiquitously air
tight. The thin disc model of line profiles in AGN and in X-ray binaries should
be bench marked against other plausible possibilities. One proposed alternative
is an engine consisting of dense clouds embedded in an optically thin,
geometrically thick X-ray emitting engine. This model is further motivated by
studies of geometrically thick engines such as advection dominated accretion
flows (ADAFs). Here we compute the reprocessed iron line profiles from dense
clouds embedded in geometrically thick, optically thin X-ray emitting discs
near a Schwarzchild black hole. We consider a range of cloud distributions and
disc solutions, including ADAFs, pure radial infall, and bipolar outflows. We
find that such models can reproduce line profiles similar to those from
geometrically thin, optically thick discs and might help alleviate some of the
problems encountered from the latter.

</DOC>
<DOC>
<DOCNO> 100702 </DOCNO>
Local calibrations for minimizers of the Mumford-Shah functional with a


  Using a calibration method, we prove that, if w is a function which satisfies
all Euler conditions for the Mumford-Shah functional on a two-dimensional
domain, and the discontinuity set S of w is a regular curve connecting two
boundary points, then there exists a uniform neighbourhood U of S such that w
is a minimizer of the Mumford-Shah functional on U with respect to its own
boundary conditions. We show that Euler conditions do not guarantee in general
the minimality of w in the class of functions with the same boundary value of w
and whose extended graph is contained in a neighbourhood of the extended graph
of w, and we give a sufficient condition in terms of the geometrical properties
of the domain and the discontinuity set under which this kind of minimality
holds.

</DOC>
<DOC>
<DOCNO> 151756 </DOCNO>
AdS/CFT correspondence in cosmology


  The attempt to understand if AdS/CFT correspondence may be realized as the
one between some AdS-like cosmological space and CFT living on the boundary is
made. In order to obtain such cosmology we exchange the time and radial
coordinates in d5 Schwarzschild-anti de Sitter (S-AdS) BH (with corresponding
signature change). The test on proportionality of free energies from such d5
cosmological space (after AdS/CFT identification of parameters) and from ${\cal
N}=4$ SU(N) super Yang-Mills quantum theory is successfully passed.

</DOC>
<DOC>
<DOCNO> 118744 </DOCNO>
Double-Mode Stellar Pulsations


  The status of the hydrodynamical modelling of nonlinear multi-mode stellar
pulsations is discussed. The hydrodynamical modelling of steady double-mode
(DM) pulsations has been a long-standing quest that is finally being concluded.
Recent progress has been made thanks to the introduction of turbulent
convection in the numerical hydrodynamical codes which provide detailed results
for individual models. An overview of the modal selection problem in the HR
diagram can be obtained in the form of bifurcation diagrams with the help of
simple nonresonant amplitude equations that capture the DM phenomenon.

</DOC>
<DOC>
<DOCNO> 13893 </DOCNO>
On the chromatic roots of generalized theta graphs


  The generalized theta graph \Theta_{s_1,...,s_k} consists of a pair of
endvertices joined by k internally disjoint paths of lengths s_1,...,s_k \ge 1.
We prove that the roots of the chromatic polynomial $pi(\Theta_{s_1,...,s_k},z)
of a k-ary generalized theta graph all lie in the disc |z-1| \le [1 + o(1)]
k/\log k, uniformly in the path lengths s_i. Moreover, we prove that
\Theta_{2,...,2} \simeq K_{2,k} indeed has a chromatic root of modulus [1 +
o(1)] k/\log k. Finally, for k \le 8 we prove that the generalized theta graph
with a chromatic root that maximizes |z-1| is the one with all path lengths
equal to 2; we conjecture that this holds for all k.

</DOC>
<DOC>
<DOCNO> 122163 </DOCNO>
Kinematics and photometry as complementary tools in the study of barred


  Recent advances in observational techniques and theoretical modelling of
galaxy kinematics allow us to use more than just optical morphology to discern
the structure and dynamics of galaxies. Here, we show for three barred galaxies
(UGC 10205, NGC 6221 and NGC4340) that both kinematics and photometry are
necessary to fully understand the properties of these galaxies. Kinematic and
spectrophotometric data enable us to detect structures such as bars and gas
shocks that are not directly visible in the images; conversely, imaging can be
crucial for understanding the kinematic and dynamical behavior of a galaxy.

</DOC>
<DOC>
<DOCNO> 10383 </DOCNO>
Stable Vortex Configurations in a Cylinder


  We calculate stable arrangements for a single superfluid vortex pinned to the
wall of a stationary cylindrical container. We find that, independent of the
details of the pinning site, stable vortices must subtend most of the cell
horizontally and cannot be vertical or nearly vertical. More generally, the
geometry of a container severely limits the possible vortex configurations,
making macroscopic trapped vortices less common than previously believed.

</DOC>
<DOC>
<DOCNO> 9403 </DOCNO>
Observation of coherent backscattering of light by cold atoms


  Coherent backscattering (CBS) of light waves by a random medium is a
signature of interference effects in multiple scattering. This effect has been
studied in many systems ranging from white paint to biological tissues.
Recently, we have observed CBS from a sample of laser-cooled atoms, a
scattering medium with interesting new properties. In this paper we discuss
various effects, which have to be taken into account for a quantitative study
of coherent backscattering of light by cold atoms.

</DOC>
<DOC>
<DOCNO> 174577 </DOCNO>
Pion Imaging at the AGS


  Source imaging analysis was performed on two-pion correlations in central Au
+ Au collisions at beam energies between 2 and 8$A$ GeV. We apply the imaging
technique by Brown and Danielewicz, which allows a model-independent extraction
of source functions with useful accuracy out to relative pion separations of
about 20 fm. We found that extracted source functions have Gaussian shapes.
Values of source functions at zero separation are almost constant across the
energy range under study. Imaging results are found to be consistent with
conventional source parameters obtained from a multidimensional HBT analysis.

</DOC>
<DOC>
<DOCNO> 101446 </DOCNO>
Local subgroupoids II: Examples and properties


  The notion of local subgroupoid as a generalisation of a local equivalence
relation was defined in a previous paper by the first two authors. Here we use
the notion of star path connectivity for a Lie groupoid to give an important
new class of examples, generalising the local equivalence relation of a
foliation, and develop in this new context basic properties of coherence, due
earlier to Rosenthal in the special case. These results are required for
further applications to holonomy and monodromy.

</DOC>
<DOC>
<DOCNO> 71564 </DOCNO>
Interplay of friction and noise and enhancement of disoriented chiral


  Using the Langevin equation for the linear $\sigma$ model, we have
investigated the effect of friction and noise on the possible disoriented
chiral condensate formation. Friction and noise are supposed to suppress
longwavelength oscillations and growth of disoriented chiral condensate
domains. Details simulation shows that for heavy ion collisions, interplay of
friction and noise occur in such a manner that formation of disoriented chiral
condensate domains are enhanced.

</DOC>
<DOC>
<DOCNO> 11567 </DOCNO>
Consistency of Microcanonical and Canonical Finite-Size Scaling


  Typically, in order to obtain finite-size scaling laws for quantities in the
microcanonical ensemble, an assumption is taken as a starting point. In this
paper, consistency of such a Microcanonical Finite-Size Scaling Assumption with
its commonly accepted canonical counterpart is shown, which puts Microcanonical
Finite-Size Scaling on a firmer footing.

</DOC>
<DOC>
<DOCNO> 10915 </DOCNO>
Reparametrization invariance: a gauge-like symmetry of ultrametrically


  The reparametrization transformation between ultrametrically organised states
of replicated disordered systems is explicitly defined. The invariance of the
longitudinal free energy under this transformation, i.e. reparametrization
invariance, is shown to be a direct consequence of the higher level symmetry of
replica equivalence. The double limit of infinite step replica symmetry
breaking and n=0 is needed to derive this continuous gauge-like symmetry from
the discrete permutation invariance of the n replicas. Goldstone's theorem and
Ward identities can be deduced from the disappearence of the second (and higher
order) variation of the longitudinal free energy. We recall also how these and
other exact statements follow from permutation symmetry after introducing the
concept of "infinitesimal" permutations.

</DOC>
<DOC>
<DOCNO> 68282 </DOCNO>
Angular Distribution of Charming B -> V V Decays and Time Evolution


  Angular distributions of a B meson decaying into two vector mesons are
discussed with emphasis on time evolution effects on the complete set of
amplitude bilinears. Time integrated quantities are suggested to observe
substantial CP violation in decays with charm quarks in the final state
particles. Relations among the nine observables at $t=0$ are found to be useful
for a consistency check of experimentally extracted quantities. Numerical
estimates of the nine observables are made using form factor models and the
assumption of the factorization hypothesis. Branching ratio asymmetries for
B_u^+ -> D^{*+} \bar D^{*0} and B_d -> D^{*+} D^{*-} can be as large as -3% and
-4%, respectively.

</DOC>
<DOC>
<DOCNO> 12221 </DOCNO>
Cantor Spectra for Double Exchange Model


  We numerically study energy spectra and localization properties of the double
exchange model at irrational filling factor. To obtain variational ground
state, we use a mumerical technique in momentum space by ``embedded'' boundary
condition which has no finite size effect a priori. Although the Hamiltonian
has translation invariance, the ground state spontaneously exhibits a
self-similarity. Scaling and multi-fractal analysis for the wave functions are
performed and the scaling indices $\alpha$'s are obtained. The energy spectrum
is found to be a singular continuous, so-called the Cantor set with zero
Lebesque measure.

</DOC>
<DOC>
<DOCNO> 122250 </DOCNO>
Saving Astronomical Treasures


  The time domain is under-exploited in an astrophysical context, because the
large photographic plate collections are almost never consulted by young
astronomers. This is a result of lack of education of the more recent
generations of astronomers, and of the deluge of terabyte-size datasets
produced by new observations. Yet astronomical plates represent a unique set of
resources and their quality does NOT improve with time. We point out valuable
scientific projects that can be conducted with archival images and describe a
first step to realize this at the Uccle Observatory, in Belgium.

</DOC>
<DOC>
<DOCNO> 12778 </DOCNO>
Composite Spin Waves, Quasi-Particles and Low Temperature resistivity in


  We make a quantum description of the electron low temperature properties of
double exchange materials. In these systems there is a strong coupling between
the core spin and the carriers spin. This large coupling makes the low energy
spin waves to be a combination of ion and electron density spin waves. We study
the form and dispersion of these composite spin wave excitations. We also
analyze the spin up and down spectral functions of the temperature dependent
quasi-particles of this system. Finally we obtain that the thermally activated
composite spin waves renormalize the carriers effective mass and this gives
rise to a low temperature resistivity scaling as T ^{5/2}.

</DOC>
<DOC>
<DOCNO> 122433 </DOCNO>
Stellar mass-to-light ratios and the Tully-Fisher relation


  We have used a suite of simplified spectrophotometric spiral galaxy evolution
models to argue that there are substantial variations in stellar mass-to-light
ratios (M/Ls) within and among galaxies, amounting to factors of between 3 and
7 in the optical, and factors of 2 in the near-infrared. Under the assumption
of a universal spiral galaxy IMF, our models show a strong and robust
correlation between stellar M/L and the optical colors of the integrated
stellar populations. Using observed maximum disk M/Ls we conclude that a
Salpeter Initial Mass Function (IMF) has too many low-mass stars per unit
luminosity, but that an IMF similar to the Salpeter IMF at the high-mass end
with less low-mass stars (giving stellar M/Ls 30% or more lower than the
Salpeter value) is consistent with the maximum disk constraints. We apply the
model trends in stellar M/L with color to the Tully-Fisher (TF) relation. We
find that the stellar mass TF relation is relatively steep and has modest
scatter, and is independent of the passband and color used to derive the
stellar masses. The difference in slope between the optical (especially blue)
and near-infrared TF relations is due to the combined effects of dust
attenuation and stellar M/L variations with galaxy mass. We find that the
baryonic TF relation has a slope of 3.5 (with random and systematic errors of
+/- 0.2 each). Since we have normalized the stellar M/L to be as high as can
possibly be allowed by maximum disk constraints, the slope of the baryonic TF
relation will be somewhat shallower than 3.5 if all disks are substantially
sub-maximal. [Abridged]

</DOC>
<DOC>
<DOCNO> 11825 </DOCNO>
Direct Observation of Superheating and Supercooling of Vortex Matter


  We report the first observation of a striking history dependence of the
structure function of the vortex matter in the peak effect regime in a Nb
single crystal by using small angle neutron scattering combined with {\it in
situ} magnetic susceptibility measurements. Metastable phases of vortex matter,
supercooled vortex liquid and superheated vortex solid, have been identified.
We interpret our results as direct structural evidence for a first-order
solid-liquid transition at the peak effect.

</DOC>
<DOC>
<DOCNO> 8591 </DOCNO>
Phase Transitions in Confined Antiferromagnets


  Confinement effects on the phase transitions in antiferromagnets are studied
as a function of the surface coupling v and the surface field h for bcc(110)
films. Unusual topologies for the phase diagram are attained for particular
combinations of v and h. It is shown that some of the characteristics of the
finite-temperature behavior of the system are driven by its low-temperature
properties and consequently can be explained in terms of a ground-state
analysis. Cluster variation free energies are used for the investigation of the
finite temperature behavior.

</DOC>
<DOC>
<DOCNO> 68245 </DOCNO>
Effects of the right-handed neutrinos on \Delta S = 2 and \Delta B = 2


  We discuss an extra source of CP and flavor violations in supersymmetric
SU(5) grand unified model with the right-handed neutrinos. In such a model, the
right-handed down-type squarks \tilde{d}_R interact with the right-handed
neutrinos above the GUT scale, and the renormalization group effect can
generate sizable off-diagonal elements in the mass matrix of \tilde{d}_R.
Because of new Yukawa phases which exist in the SU(5) model, these off-diagonal
elements have, in general, large CP violating phases. The renormalization group
induced off-diagonal elements affect the K and B decays. In particular, in this
model, supersymmetric contribution to the \epsilon_K parameter can be as large
as the currently measured experimental value, and hence the effect might be
seen as an anomaly in the on-going test of the Cabibbo-Kobayashi-Maskawa
triangle.

</DOC>
<DOC>
<DOCNO> 99343 </DOCNO>
An inverse problem of ocean acoustics


  The inverse problem of finding the refraction coefficient of a shallow ocean
from the observation of the extra Cauchy data for the acoustic field at the
surface of the ocean is studied. Uniqueness theorem is proved and a
reconstruction algorithm is obtained.
 Comments are given on the related results in the literature.

</DOC>
<DOC>
<DOCNO> 85645 </DOCNO>
Lagrangian Noether symmetries as canonical transformations


  We prove that, given a time-independent Lagrangian defined in the first
tangent bundle of configuration space, every infinitesimal Noether symmetry
that is defined in the $n$-tangent bundle and is not vanishing on-shell, can be
written as a canonical symmetry in an enlarged phase space, up to constraints
that vanish on-shell. The proof is performed by the implementation of a change
of variables from the the $n$-tangent bundle of the Lagrangian theory to an
extension of the Hamiltonian formalism which is particularly suited for the
case when the Lagrangian is singular. This result proves the assertion that any
Noether symmetry can be canonically realized in an enlarged phase space. Then
we work out the regular case as a particular application of this ideas and
rederive the Noether identities in this framework. Finally we present an
example to illustrate our results.

</DOC>
<DOC>
<DOCNO> 69988 </DOCNO>
Inclusive and Semi-Inclusive Polarized DIS Data Revisited


  We perform a combined next to leading order analysis to both inclusive and
semi-inclusive polarized deep inelastic scattering data, assessing the impact
of new data in the extraction of the sea quark and gluon spin dependent
densities. In particular, we find that semi-inclusive data show a clear
preference for a positive 'Delta ubar' distribution, although are almost
insensitive to different alternatives to 'Delta dbar'.

</DOC>
<DOC>
<DOCNO> 69847 </DOCNO>
Manifest covariance and the Hamiltonian approach to mass gap in


  In earlier work we have given a Hamiltonian analysis of Yang-Mills theory in
(2+1) dimensions showing how a mass gap could arise. In this paper,
generalizing and covariantizing from the mass term in the Hamiltonian analysis,
we obtain two manifestly covariant and gauge-invariant mass terms which can be
used in a resummation of standard perturbation theory to study properties of
the mass gap.

</DOC>
<DOC>
<DOCNO> 102661 </DOCNO>
Construction of Doubly Periodic Solutions via the Poincare-Lindstedt


  Doubly periodic (periodic both in time and in space) solutions for the
Lagrange-Euler equation of the (1+1)-dimensional scalar Phi^4 theory are
considered. The nonlinear term is assumed to be small, and the
Poincare-Lindstedt method is used to find asymptotic solutions in the standing
wave form. The principal resonance problem, which arises for zero mass, is
solved if the leading-order term is taken in the form of a Jacobi elliptic
function. It have been proved that the choice of elliptic cosine with fixed
value of module k (k=0.451075598811) as the leading-order term puts the
principal resonance to zero and allows us constructed (with accuracy to third
order of small parameter) the asymptotic solution in the standing wave form. To
obtain this leading-order term the computer algebra system REDUCE have been
used. We have appended the REDUCE program to this paper.

</DOC>
<DOC>
<DOCNO> 10917 </DOCNO>
Dynamic Impedance of Two-Dimensional Superconducting Films Near the


  The sheet impedances, Z(w,T), of several superconducting a-Mo77Ge23 films and
one In/InOx film have been measured in zero field using a two-coil mutual
inductance technique at frequencies from 100 Hz to 100 kHz. Z(w,T) is found to
have three contributions: the inductive superfluid, renormalized by nonvortex
phase fluctuations; conventional vortex-antivortex pairs, whose contribution
turns on very rapidly just below the usual Kosterlitz-Thouless-Berezinskii
unbinding temperature; and an anomalous contribution. The latter is
predominantly resistive, persists well below the KTB temperature, and is weakly
dependent on frequency down to remarkably low frequencies, at least 100 Hz. It
increases with T as e-U'(T)/kT, where the activation energy, U'(T), is about
half the energy to create a vortex-antivortex pair, indicating that the
frequency dependence is that of individual excitations, rather than critical
behavior.

</DOC>
<DOC>
<DOCNO> 118001 </DOCNO>
C32, A Young Star Cluster in IC 1613


  The Local Group irregular galaxy IC 1613 has remained an enigma for many
years because of its apparent lack of star clusters. We report the successful
search for clusters among several of the candidate objects identified many
years ago on photographic plates. We have used a single HST WFPC2 pointing and
a series of images obtained with the WIYN telescope under exceptional seeing
conditions, examining a total of 23 of the previously published candidates. All
but six of these objects were found to be either asterisms or background
galaxies. Five of the six remaining candidates possibly are small, sparse
clusters and the sixth, C32, is an obvious cluster. It is a compact, young
object, with an age of less than 10 million years and a total absolute
magnitude of M_V = -5.78+/-0.16 within a radius of 13 pc.

</DOC>
<DOC>
<DOCNO> 122587 </DOCNO>
The Red-Sequence Cluster Survey


  The Red-Sequence Cluster Survey (RCS) is a new galaxy cluster survey designed
to provide a large sample of optically selected 0.1$<$z$<$1.4 clusters. The
planned survey data are 100 square degrees of two color ($R$ and $z'$) imaging,
with a 5$\sigma$ depth $\sim$2 mag past M$^{*}$ at $z=1$. The combined depth
and area of the RCS make it the widest field, moderately deep survey ever
undertaken using 4m class telescopes. This paper gives a brief outline of the
RCS survey, with particular emphasis on the data reduction strategy. The
remainder of the paper focuses on preliminary results from the first set of
completely reduced data ($\sim$10 deg$^2$, of the $\sim$60 deg$^2$ in hand). We
provide a new example of a rich $z>1$ cluster, illustrative of the dozens
discovered in the data so far. Some of the possible science to come from the
RCS is illustrated by a qualitative indication of $\Omega_{M}$ from the first
1/10th of the survey data. A high-precision measurement of the 2-point
correlation function of luminous early-type galaxies at $0.4<z<1.2$ is also
shown.

</DOC>
<DOC>
<DOCNO> 170111 </DOCNO>
Quantization of a Constant of Motion for the Harmonic Oscillator with a


  The quantization of a constant of motion for the harmonic oscillator with a
time-explicitly depending external force is carried out. This quantization
approach is compared with the normal Hamiltonian quantization approach.
Numerical results show that there are qualitative and quantitative differences
for both approaches, suggesting that the quantization of this constant of
motion may be verified experimentally.

</DOC>
<DOC>
<DOCNO> 151137 </DOCNO>
Noncommutative Open strings, D-brane and Duality


  We consider open strings ending on D-branes in the presence of constant
metric, G, antisymmetric tensor, B and gauge field, A. The Hamiltonian is
manifestly invariant under a global noncompact group; strikingly similar to
toroidally compactified closed string Hamiltonian. The evolution equations for
the string coordinates, $\{X^i \}$ and their dual partners, $\{Y_i \}$, are
combined to obtain equations of motion invariant under the noncompact symmetry
transformations. We show that one can start from a noncommutative theory, with
nonvanishing G and B and mixed boundary conditions and then go over to a dual
theory whose coordinates obey Dirichlet boundary conditions. It is possible to
generate B-field by implementing the noncompact symmetry transformation. The
connection between this duality transformation and Seiberg-Witten map is
discussed.

</DOC>
<DOC>
<DOCNO> 13926 </DOCNO>
Dynamics of Symmetry Breaking and Tachyonic Preheating


  We reconsider the old problem of the dynamics of spontaneous symmetry
breaking using 3d lattice simulations, and develop a theory of tachyonic
preheating, which occurs due to the spinodal instability of the scalar field.
Tachyonic preheating is so efficient that symmetry breaking typically completes
within a single oscillation of the field distribution as it rolls towards the
minimum of its effective potential. As an application of this theory we
consider preheating in the hybrid inflation scenario, including SUSY-motivated
F-term and D-term inflationary models. We show that preheating in hybrid
inflation is typically tachyonic and the stage of oscillations of a homogeneous
component of the scalar fields driving inflation ends after a single
oscillation. Our results may also be relevant for the theory of the formation
of disoriented chiral condensates in heavy ion collisions.

</DOC>
<DOC>
<DOCNO> 121476 </DOCNO>
Three-Dimensional Magnetohydrodynamical Accretion Flows into Black Holes


  Outflows and convective motions in accretion flows have been intensively
discussed recently in the context of advection-dominated accretion flow (ADAF)
based on two-dimensional (2D) and three-dimensional (3D) hydrodynamical
simulations. We, however, point that without proper treatments of the disk
magnetic fields, a major source of viscosity, one can never derive general,
firm conclusions concerning the occurrence of outflows and convection. We
analyzed the 3D MHD numerical simulation data of magnetized accretion flows
initially threaded by weak toroidal magnetic fields, finding large-scale
convective motions dominating near the black hole. In contrast, outflows occur
only temporarily and are not very significant in our simulations. If there grow
strong vertical fields somehow, however, formation of bi-polar jets is
inevitable. It is claimed that radiation could be dominant at the outermost
zones of the convective disks because of outward energy flow by convection,
however, this is no longer the case in convective MHD flows, since accretion
energy can be released via magnetic reconnection in the inner parts. Such
reconnection leads to sporadic flare events, thus producing substantial
variability in out-going radiation.

</DOC>
<DOC>
<DOCNO> 116768 </DOCNO>
Lattice Matching with a Quadrupole Missing


  The lattice for the present design of the TESLA Linear Collider with
integrated X-Ray Laser Facility is basically a FODO structure with constant
beta-function. There are more than 800 individually powered superconducting
quadrupoles to focus the beam in the two main linear accelerators (each with a
length of 15 km). For the availability of the beams it is important that a
power supply failure or even a magnet failure does not cause a significant down
time of the linac. It is demonstrated that the beta-function can be matched
with a quadrupole "missing". One part of the main linac (up-to 50 GeV) will be
used to accelerate the High Energy Physics beam and the Free Electron Laser
drive beam with different accelerating gradients. Therefore the betatron phase
advance will be 60 deg. or 90 deg. depending on the beam energy. It is shown
that even in that case it is possible to match the lattice simultaneously for
both beams with a quadrupole missing.

</DOC>
<DOC>
<DOCNO> 152509 </DOCNO>
Commutation relations for surface operators in six-dimensional (2, 0)


  The A_{N - 1} (2, 0) superconformal theory has an observable associated with
every two-cycle in six dimensions. We make a natural guess for the commutation
relations of these operators, which reduces to the commutation relations of
Wilson and 't Hooft lines in four-dimensional SU(N) N = 4 super Yang-Mills
theory upon compactification on a two-torus. We then verify these commutation
relations by considering the theory at a generic point of its moduli space and
including in the surface operators only contributions from the light degrees of
freedom, which amount to N - 1 (2, 0) tensor multiplets.

</DOC>
<DOC>
<DOCNO> 10414 </DOCNO>
Free cooling and inelastic collapse of granular gases in high dimensions


  The connection between granular gases and sticky gases has recently been
considered, leading to the conjecture that inelastic collapse is avoided for
space dimensions higher than 4. We report Molecular Dynamics simulations of
hard inelastic spheres in dimensions 4, 5 and 6. The evolution of the granular
medium is monitored throughout the cooling process. The behaviour is found to
be very similar to that of a two-dimensional system, with a shearing-like
instability of the velocity field and inelastic collapse when collisions are
inelastic enough, showing that the connection with sticky gases needs to be
revised.

</DOC>
<DOC>
<DOCNO> 84221 </DOCNO>
On PSR1913+16


  There are reference frames for which both stars of binary radio-pulsar
PSR1913+16 are at rest. As a consequence, PSR1913+16 does not emit gravity
waves. (If the accelerated bodies should send out a gravitational radiation,
they would represent a class of physically privileged systems. But this is
forbidden by general relativity.)

</DOC>
<DOC>
<DOCNO> 83287 </DOCNO>
Universally Quantified Interval Constraint Solving: an application to


  Non-linear real constraint systems with universally/existentially quantified
variables often need be solved in such contexts as control design or sensor
planning. To date, these systems are mostly handled by computing a
quantifier-free equivalent form by means of Cylindrical Algebraic/Trigonometric
Decomposition (CAD/CTD). However, CAD and CTD restrict their input to be
conjunctions and disjunctions of (trigonometric) polynomial constraints, while
some applications such as camera control involve systems with arbitrary forms
where time is the only universally quantified variable. In this paper, the
handling of universally quantified variables is first related to the
computation of inner-approximations of real relations. Algorithms for solving
non-linear real constraint systems with universally quantified variables are
then presented along with the theoretical framework on inner-approximation of
relations supporting them. These algorithms are based on the computation of
outer-approximations of the solution set of the negation of involved
constraints. An application to the devising of a declarative modeller for
expressing camera motion using a cinematic language is described, and results
on a prototype are discussed.

</DOC>
<DOC>
<DOCNO> 11619 </DOCNO>
Chiral feedback for p-wave superconductors


  In a quasi-two-dimensional $ p $-wave superconductor there find six Cooper
pairing states which are degenerate within the weak-coupling approach. We show
that this degeneracy can be lifted by feedback effect favoring the so-called
chiral $ p $-wave state. This effect is based on the anomalous coupling between
charge and current in a system with broken time reversal symmetry and parity.

</DOC>
<DOC>
<DOCNO> 119805 </DOCNO>
On the Relation Between Peak Luminosity and Parent Population of Type Ia


  We study the properties of Type Ia Supernovae (SNe Ia) as functions of the
radial distance from their host galaxy centers. Using a sample of 62 SNe Ia
with reliable luminosity, reddening, and decline rate determinations, we find
no significant radial gradients of SNe Ia peak absolute magnitudes or decline
rates in elliptical+S0 galaxies, suggesting that the diversity of SN properties
is not related to the metallicity of their progenitors. We do find that the
range in brightness and light curve width of supernovae in spiral galaxies
extends to brighter, broader values. These results are interpreted as support
for an age, but not metallicity, related origin of the diversity in SNe Ia. If
confirmed with a larger and more accurate sample of data, the age-luminosity
relation would offer a new and powerful tool to probe the ages and age
gradients of stellar populations in galaxies at redshift as high as $z\sim1-2$.
The absence of significant radial gradients in the peak $\rm (B-V)_0$ and $\rm
(V-I)_0$ colors of SNe Ia supports the redding correction method of Phillips et
al (1999). We find no radial gradient in residuals from the SN Ia
luminosity-width relation, suggesting that the relation is not affected by
properties of the progenitor populations and supporting the reliability of
cosmological results based upon the use of SNe Ia as distance indicators.

</DOC>
<DOC>
<DOCNO> 121475 </DOCNO>
The Origin of a Chemically Enriched lya Absorption System at z=0.167


  We present the first detailed analysis of the chemical abundances, ionization
state, and origin of a partial Lyman limit system (N(\hI) ~ 10^{16} \cmjj) at
low redshift (z=0.167 towards PKS0405-1219). Two galaxies at ~ 70 h^{-1} kpc
projected distance to the QSO have been identified at the absorber redshift. We
analyze an echelle spectrum of the QSO obtained with the Space Telescope
Imaging Spectrograph and find that this absorption system exhibits associated
lines produced by C^+, N^+, O^0, Si^+, Si^{++}, Si^{+3}, Fe^+, and Fe^{++}, and
most interestingly, O^{+5} and N^{+4}. The results of our analysis show that
the partial Lyman limit system traced by various ions is likely to be embedded
in a collisionally ionized \ovi gas of larger spatial extent. Furthermore, the
partial Lyman limit system appears to have a metallicity of {\em at least} 1/10
solar and most likely solar or super solar despite the fact that no luminous
galaxies are seen within a projected distance \rho = 60 h^{-1} kpc to the QSO.
Finally, adopting the temperature estimated for the hot gas T ~ 2.5\times 10^5
K and assuming a simple isothermal halo, we estimate that the galaxy or galaxy
group that supports the extended gas may have a total mass ~ 1.5\times 10^{12}
M_\odot and a gas number density \apl 3\times 10^{-5} cm^{-3}.

</DOC>
<DOC>
<DOCNO> 100927 </DOCNO>
Arithmetic structure of CMSZ fake projective planes


  We prove that the fake projective planes constructed from the diadic discrete
group discovered by Cartwright, Mantero, Steger, and Zappa are connected
Shimura varieties associated to a certain unitary group. The necessary Shimura
data, as well as the unitary group, are explicitly described. We also give a
field of definition of these fake projective planes.

</DOC>
<DOC>
<DOCNO> 84852 </DOCNO>
Monopole-Anitmonopole Solutions of Einstein-Yang-Mills-Higgs Theory


  We construct static axially symmetric solutions of SU(2)
Einstein-Yang-Mills-Higgs theory in the topologically trivial sector,
representing gravitating monopole--antimonopole pairs, linked to the
Bartnik-McKinnon solutions.

</DOC>
<DOC>
<DOCNO> 117435 </DOCNO>
Evidence for TeV Emission from GRB 970417a


  Milagrito, a detector sensitive to very high energy gamma rays, monitored the
northern sky from February 1997 through May 1998. With a large field of view
and a high duty cycle, this instrument was well suited to perform a search for
TeV gamma-ray bursts (GRBs). We report on a search made for TeV counterparts to
GRBs observed by BATSE. BATSE detected 54 GRBs within the field of view of
Milagrito during this period. An excess of events coincident in time and space
with one of these bursts, GRB 970417a, was observed by Milagrito. The excess
has a chance probability of $2.8 \times 10^{-5}$ of being a fluctuation of the
background. The probability for observing an excess at least this large from
any of the 54 bursts is $1.5 \times 10^{-3}$. No significant correlations were
detected from the other bursts.

</DOC>
<DOC>
<DOCNO> 71667 </DOCNO>
Experimental Signatures of Anomaly Induced DCC Formation


  We discuss characteristic experimental signatures related to the formation of
domains of disoriented chiral condensate (DCC) triggered by the axial anomaly
in relativistic heavy ion collisions. We predict that the enhancement of the
fraction of neutral pions compared to all pions depends on the angle of
emission with respect to the scattering plane and is concentrated at small
transverse momentum and small rapidity in the center-of-mass frame. The
anisotropy with respect to the reaction plane is also observable in the
inclusive photon distribution.

</DOC>
<DOC>
<DOCNO> 13456 </DOCNO>
Superposition of photon- and phonon- assisted tunneling in coupled


  We report on electron transport through an artificial molecule formed by two
tunnel coupled quantum dots, which are laterally confined in a two-dimensional
electron system of an Al$_x$Ga$_{1-x}$As/GaAs heterostructure. Coherent
molecular states in the coupled dots are probed by photon-assisted tunneling
(PAT). Above 10 GHz, we observe clear PAT as a result of the resonance between
the microwave photons and the molecular states. Below 8 GHz, a pronounced
superposition of phonon- and photon-assisted tunneling is observed. Coherent
superposition of molecular states persists under excitation of acoustic
phonons.

</DOC>
<DOC>
<DOCNO> 178971 </DOCNO>
Calculations of three-body observables in ^8B breakup


  We discuss calculations of three-body observables for the breakup of ^8B on a
^{58}Ni target at low energy using the coupled discretised continuum channels
approach. Calculations of both the angular distribution of the ^7Be fragments
and their energy distributions are compared with those measured at several
laboratory angles. In these observables there is interference between the
breakup amplitudes from different spin-parity excitations of the projectile.
The resulting angle and the energy distributions reveal the importance of the
higher-order continuum state couplings for an understanding of the
measurements.

</DOC>
<DOC>
<DOCNO> 119933 </DOCNO>
Mid-infrared imaging and spectrophotometry of N 66 in the SMC with


  We present observations with the mid-infrared camera ISOCAM on board ISO of
the major star-forming region N66 in the Small Magellanic Cloud and of its
surroundings. These observations were performed with broad filters and the CVF
giving a spectral resolution of about 40. In addition, CO(2-1) data are
presented, allowing us to identify and study how hot dust relates with the
different phases of the Interstellar Medium present in N66. The spectra are
dominated by the strong emission of fine structure line. Monochromatic maps
have been made in the [NeIII] 15.6 microns and [SIV] 10.5 microns line. There
are significant differences between their distributions, due to the effects of
density and of shocks. Aromatic Infrared Bands are seen at various places in
the field but they are generally faint. They exhibit a variety of shapes and
relative intensities, suggesting that a diversity of carbonaceous materials are
present. Silicate emission is also clearly visible in the central condensation
and in a few others and emission from hot small grains longward of 10 microns
is present in the whole region. All these dust components are heated by the
very strong far UV radiation of the many young, massive stars contained in the
region. The interstellar radiation field (ISRF) at 1600 A is >= 10^5 times the
ISRF of the solar neighborhood in the peaks of MIR emission. The relative
contributions of the dust components to the MIR spectra seem to depend on the
intensity and the hardness of the far UV field. In general the 15/6.75 microns
intensity ratio is higher than in relatively quiescent galactic regions but it
is not as high as expected for a linear increase with ISRF. We interpret this
behavior as due to the destruction of both AIBs carriers and VSGs in a very
high ISRF.

</DOC>
<DOC>
<DOCNO> 118563 </DOCNO>
Accretion by Galaxies


  Both theory and observation indicate that galaxies like the Milky Way accrete
matter at the rate of a few Msun per year.

</DOC>
<DOC>
<DOCNO> 122058 </DOCNO>
Collimating, relativistic, magnetic jets from rotating disks


  The magnetic flux distribution is determined by the solution of the
Grad-Shafranov equation. With differential rotation, i.e. the variation of the
iso-rotation parameter, the shape of the light surface must be calculated in an
iterative way. For the first time, we have calculated the force-free magnetic
structure of truly two-dimensional, relativistic jets, anchored in a
differentially rotating disk. Such an approach allows for a direct connection
between parameters of the central source (mass, rotation) and the extension of
the radio jet. We present an analytical estimate for the jet opening angle
along the asymptotic branches of the light surface. In general, differential
rotation of the iso-rotation parameter leads to an increase of the jet opening
angle. Comparison to the M87 jet shows agreement in the collimation distance.
We derive a light cylinder radius of the M87 jet of 50 Schwarzschild radii.

</DOC>
<DOC>
<DOCNO> 101946 </DOCNO>
Identification of multilayered particles from scattering data by a


  A multilayered particle is illuminated by plane acoustic or electromagnetic
waves of one or several frequencies. We consider the inverse scattering problem
for the identification of the layers and of the refraction coefficients of the
scatterer in a non-Born region of scattering. Local deterministic and global
probabilistic minimization methods are studied. A special Reduction Procedure
is introduced to reduce the dimensionality of the minimization space. Deep's
and the Multilevel
 Single-Linkage methods for global minimization are used for the solution of
the inverse problem. Their performance is analyzed for various multilayer
configurations.

</DOC>
<DOC>
<DOCNO> 100749 </DOCNO>
An Algebra of Skew Primitive Elements


  We study the various term operations on the set of skew primitive elements of
Hopf algebras, generated by skew primitive semi-invariants of an Abelian group
of grouplike elements. All 1-linear binary operations are described and
trilinear and quadrilinear operations are given a detailed treatment. Necessary
and sufficient conditions for the existence of multilinear operations are
specified in terms of the property of particular noncommutative polynomials
being linearly dependent and of one arithmetic condition. We dub the conjecture
that this condition implies, in fact, the linear dependence of the polynomials
in question and so is itself sufficient (a proof of this conjecture see in "An
existence condition for multilinear quantum operations," Journal of Algebra,
217, 1999, 188-228).

</DOC>
<DOC>
<DOCNO> 85092 </DOCNO>
Conservation laws in the teleparallel theory of gravity


  We study the conservation laws associated with the asymptotic Poincare
symmetry of spacetime in the general teleparallel theory of gravity. Demanding
that the canonical Poincare generators have well defined functional derivatives
in a properly defined phase space, we obtain the improved form of the
generators, containing certain surface terms. These terms are shown to
represent the values of the related conserved charges: energy-momentum and
angular momentum.

</DOC>
<DOC>
<DOCNO> 69528 </DOCNO>
Parton counting: physical and computational complexity of multi-jet


  We present an enumeration of all possible amplitudes that contribute to an
n-jet process in QCD. We estimate the number of amplitudes for large number of
jets and determine the actual number of amplitudes to be calculated, which is
smaller due to relabelling among (massless) quark flavours.

</DOC>
<DOC>
<DOCNO> 121296 </DOCNO>
Kinematics of log N(HI)~17 [cm^-2], Metal-Rich Gas Extended Around


  The kinematics of metal-enriched, low-ionization gas at large galactocentric
distances are compared to the host galaxy properties and are discussed in the
context of global galaxy evolution.

</DOC>
<DOC>
<DOCNO> 9242 </DOCNO>
Small Angle Shubnikov-de Haas Measurements in Silicon MOSFET's: the


  Measurements in magnetic fields applied at small angles relative to the
electron plane in silicon MOSFETs indicate a factor of two increase of the
frequency of Shubnikov-de Haas oscillations at H>H_{sat}. This signals the
onset of full spin polarization above H_{sat}, the parallel field above which
the resistivity saturates to a constant value. For H<H_{sat}, the phase of the
second harmonic of the oscillations relative to the first is consistent with
scattering events that depend on the overlap instead of the sum of the spin-up
and spin-down densities of states.

</DOC>
<DOC>
<DOCNO> 12586 </DOCNO>
Adiabatic Inversion in the SQUID, Macroscopic Coherence and Decoherence


  A procedure for demonstrating quantum coherence and measuring decoherence
times between different fluxoid states of a SQUID by using ``adiabatic
inversion'' is discussed. One fluxoid state is smoothly transferred into the
other, like a spin reversing direction by following a slowly moving magnetic
field. This is accomplished by sweeping an external applied flux, and depends
on a well-defined quantum phase between the two macroscopic states. Varying the
speed of the sweep relative to the decoherence time permits one to move from
the quantum regime, where such a well-defined phase exists, to the classical
regime where it is lost and the inversion is inhibited. Thus observing whether
inversion has taken place or not as a function of sweep speed offers the
possibility of measuring the decoherence time. Estimates with some typical
SQUID parameters are presented and it appears that such a procedure should be
experimentally possible.
  The main requirement for the feasibility of the scheme appears to be that the
low temperature relaxation time among the quantum levels of the SQUID be long
compared to other time scales of the problem, including the readout time.
Applications to the ``quantum computer'', with the level system of the SQUID
playing the role of the qbit, are briefly examined.

</DOC>
<DOC>
<DOCNO> 102012 </DOCNO>
Elementary derivations of identities for bilateral basic hypergeometric


  We give elementary derivations of several classical and some new summation
and transformation formulae for bilateral basic hypergeometric series. For
purpose of motivation, we review our previous simple proof ("A simple proof of
Bailey's very-well-poised 6-psi-6 summation", Proc. Amer. Math. Soc., to
appear) of Bailey's very-well-poised 6-psi-6 summation. Using a similar but
different method, we now give elementary derivations of some transformations
for bilateral basic hypergeometric series. In particular, these include M.
Jackson's very-well-poised 8-psi-8 transformation, a very-well-poised 10-psi-10
transformation, by induction, Slater's general transformation for
very-well-poised 2r-psi-2r series, and Slater's transformation for general
r-psi-r series. Finally, we derive some new transformations for bilateral basic
hypergeometric series of Chu-Gasper-Karlsson-Minton-type.

</DOC>
<DOC>
<DOCNO> 122615 </DOCNO>
Detection of Intracluster Gas Bulk Velocities in the Perseus and


  We report the results of spatially resolved X-ray spectroscopy of 8 different
ASCA pointings distributed symmetrically around the center of the Perseus
cluster. The outer region of the intracluster gas is roughly isothermal, with
temperature ~6-7 keV, and metal abundance ~ 0.3 Solar. Spectral analysis of the
central pointing is consistent with the presence of a cooling flow and a
central metal abundance gradient.
  A significant velocity gradient is found along an axis highly discrepant with
the major axis of the X-ray elongation. The radial velocity difference is found
to be greater than 1000 km/sMpc at the 90% confidence level. Simultaneous
fittings of GIS 2 & 3 indicate that two symmetrically opposed regions have
different radial velocities at the 95% confidence level and the F-test rules
out constant velocities for these regions at the 99% level. Intrinsic short and
long term variations of gain are unlikely (P < 0.03) to explain the velocity
discrepancies. We also report the preliminary results of a similar analysis
carried out for the Centaurus cluster, where long-exposure SIS data is
available. We also find a significant velocity gradient near the central
regions (3'-8') of Centaurus. If attributed to bulk rotation the correspondent
circular velocity is ~1500+-150km/s (at 90% confidence). The line of maximum
velocity gradient in Centaurus is near-perpendicular to the infalling galaxy
group associated with NGC 4709.

</DOC>
<DOC>
<DOCNO> 102708 </DOCNO>
Decomposition of polytopes and polynomials


  Motivated by a connection with the factorization of multivariate polynomials,
we study integral convex polytopes and their integral decompositions in the
sense of the Minkowski sum. We first show that deciding decomposability of
integral polygons is NP-complete then present a pseudo-polynomial time
algorithm for decomposing polygons. For higher dimensional polytopes, we give a
heuristic algorithm which is based upon projections and uses randomization.
Applications of our algorithm include absolute irreducibility testing and
factorization of polynomials via their Newton polytopes.

</DOC>
<DOC>
<DOCNO> 102468 </DOCNO>
Grassmannian trilogarithms


  Some time ago the first author suggested two different constructions of
Grassmannian n-logarithms. One of them works for all n, but its motivic nature
is hidden. The other is a motivic but so far available only for n=2,3,4. We
derived some general results about the first construction of Grassmannian
polylogarithms, and found an explicit relation between the two constructions of
the Grassmannian trilogarithms.

</DOC>
<DOC>
<DOCNO> 151273 </DOCNO>
Noncommutative/Nonlinear BPS Equations without Zero Slope Limit


  It is widely believed that via the Seiberg-Witten map, the linearly realized
BPS equation in the non-commutative space is related to the non-linearly
realized BPS equation in the commutative space in the zero slope limit. We show
that the relation also holds without taking the zero slope limit as is expected
from the arguments of the BPS equation for the non-Abelian Born-Infeld theory.
This is regarded as an evidence for the relation between the two BPS equations.
As a byproduct of our analysis, the non-linear instanton equation is solved
exactly.

</DOC>
<DOC>
<DOCNO> 169940 </DOCNO>
On rounds in quantum communication


  We investigate the power of interaction in two player quantum communication
protocols. Our main result is a rounds-communication hierarchy for the pointer
jumping function $f_k$. We show that $f_k$ needs quantum communication
$\Omega(n)$ if Bob starts the communication and the number of rounds is limited
to $k$ (for any constant $k$). Trivially, if Alice starts, $O(k\log n)$
communication in $k$ rounds suffices. The lower bound employs a result relating
the relative von Neumann entropy between density matrices to their trace
distance and uses a new measure of information. We also describe a classical
probabilistic $k$ round protocol with communication
$O(n/k\cdot(\log^{(k/2)}n+\log k)+k\log n)$ in which Bob starts the
communication. Furthermore as a consequence of the lower bound for pointer
jumping we show that any $k$ round quantum protocol for the disjointness
problem needs communication $\Omega(n^{1/k})$ for $k=O(1)$.

</DOC>
<DOC>
<DOCNO> 13041 </DOCNO>
Superconducting Plasma Excitation at Microwave Frequencies in Parallel


  Josephson plasma resonance has been studied in a wide microwave frequency
range between 10 and 52 GHz in a magnetic field parallel to the $ab$-plane in
under-doped $\BI$. Above about 30 GHz two resonance modes were observed: one
(LT mode) appears at low temperatures and another (HT mode) at higher
temperatures, leaving a temperature gap between two regions. These two
resonance modes exhibit a sharp contrast each other both on temperture and
magnetic field dependences and show distinct characters different entirely from
the $c$-axis Josephson plasma resonance. From temperature and field scan
experiments at various frequencies it is suggested that the LT mode can be
attributed to the coupled Josephson plasma mode with Josephson vortices, while
the HT mode is a new plasma mode associated possibly with the periodic array of
Josephson vortices.

</DOC>
<DOC>
<DOCNO> 71897 </DOCNO>
Lattice Gauge Theory - A short Primer


  In this contribution we give an introduction to the foundations and methods
of lattice gauge theory. Starting with a brief discussion of the quantum
mechanical path integral, we develop the main ingredients of lattice field
theory: functional integrals, Euclidean field theory and the space-time
discretization of scalar, fermion and gauge fields. Some of the methods used in
calculations are reviewed and illustrated by a collection of typical results.

</DOC>
<DOC>
<DOCNO> 71957 </DOCNO>
High-energy neutrino conversion and the lepton asymmetry in the universe


  We study matter effects on oscillations of high-energy neutrinos in the
Universe. Substantial effect can be produced by scattering of the neutrinos
from cosmological sources ($z\gta 1$) on the relic neutrino background,
provided that the latter has large CP-asymmetry: $\eta\equiv
(n_\nu-n_{\bar{\nu}})/n_\gamma\gta 1$, where $n_\nu$, $n_{\bar{\nu}}$ and
$n_\gamma$ are the concentrations of neutrinos, antineutrinos and photons. We
consider in details the dynamics of conversion in the expanding neutrino
background. Applications are given to the diffuse fluxes of neutrinos from
GRBs, AGN, and the decay of super-heavy relics. We find that the vacuum
oscillation probability can be modified by $\sim (10-20)%$ and in extreme cases
allowed by present bounds on $\eta$ the effect can reach $\sim 100%$.
Signatures of matter effects would consist (i) for both active-active and
active-sterile conversion, in a deviation of the numbers of events produced in
a detector by neutrinos of different flavours,
$N_{\alpha}~(\alpha=e,\mu,\tau)$, and of their ratios from the values given by
vacuum oscillations; such deviations can reach $\sim 5-15%$, (ii) for
active-sterile conversion, in a characteristic energy dependence of the ratios
$N_{e}/N_{\mu},N_{e}/N_{\tau},N_{\mu}/N_{\tau}$. Searches for these matter
effects will probe large CP and lepton asymmetries in the universe.

</DOC>
<DOC>
<DOCNO> 119923 </DOCNO>
CU Comae: a new field double-mode RR Lyrae, the most metal poor


  We report the discovery of a new double-mode RR Lyrae variable (RRd) in the
field of our Galaxy: CU Comae. CU Comae is the sixth such RRd identified to
date and is the most metal-poor RRd ever detected. Based on BVI CCD photometry
spanning eleven years of observations, we find that CU Comae has periods
P0=0.5441641 +/-0.0000049d and P1=0.4057605 +/-0.0000018d. The amplitude of the
primary (first-overtone) period of CU Comae is about twice the amplitude of the
secondary (fundamental) period. The combination of the fundamental period of
pulsation P0 and the period ratio of P1/P0=0.7457 places the variable on the
metal-poor side of the Petersen diagram, in the region occupied by M68 and M15
RRd's. A mass of 0.83 solar masses is estimated for CU Comae using an updated
theoretical calibration of the Petersen diagram. High resolution spectroscopy
(R=30,000) covering the full pulsation cycle of CU Comae was obtained with the
2.7 m telescope of the Mc Donald Observatory, and has been used to build up the
radial velocity curve of the variable. Abundance analysis done on the four
spectra taken near minimum light (phase: 0.54 -- 0.71) confirms the metal poor
nature of CU Comae, for which we derive [Fe/H]=-2.38 +/-0.20. This value places
this new RRd at the extreme metal-poor edge of the metallicity distribution of
the RR Lyrae variables in our Galaxy.

</DOC>
<DOC>
<DOCNO> 116514 </DOCNO>
Excitation of nonlinear two-dimensional wake waves in


  It is shown that an undesirable curvature of the wave front of
two-dimensional nonlinear wake wave excited in uniform plasma by a relativistic
charged bunch or laser pulse may be compensated by radial change of the
equilibrium plasma density.

</DOC>
<DOC>
<DOCNO> 40196 </DOCNO>
Exclusive B decays to charmonium final states


  We report on exclusive decays of B mesons into final states containing
charmonium using data collected with the BABAR detector at the PEP-II storage
rings. The charmonium states considered here are J/psi, psi(2S), and chi_C1.
Branching fractions for several exclusive final states, a measurement of the
decay amplitudes for the B0 --> J/psi K* decay, and measurements of the B0 and
B+ masses are presented. All of the results we present here are preliminary.

</DOC>
<DOC>
<DOCNO> 70157 </DOCNO>
Compositeness Condition and Vacuum Stability


  We consider what occurs when we remove one of the compositeness conditions
proposed by Bardeen, Hill and Lindner that leads to predictions for the top
quark mass conflicting with the experimental value. Through this consideration
the condition for the Higgs particle to be the composite particle is
reconsidered. We show that in this case, (I) the Higgs-Yukawa system of the
standard model becomes equivalent to a non-local four-fermi system at a
high-energy scale $\Lambda$, (II) The Higgs-Yukawa sector of the model becomes
useless above the scale because the vacuum state cannot be defined. We regard
the two phenomena as indications of the compositeness of the Higgs particle. It
is suggested that the new physics above $\Lambda$ contains bi-local fields.

</DOC>
<DOC>
<DOCNO> 8275 </DOCNO>
Many-particle resonances in excited states of semiconductor quantum dots


  Anderson impurity model for semiconductor quantum dot is extended to take
into account both particle and hole branches of charge excitations. It is shown
that in dots with even number of electrons where the Kondo effect is absent in
the ground state, novel midgap exciton states emerge in the energy spectrum due
to Kondo-type shake-up processes. The relevance of the model to
heterostructures doped by transition metal impurities and to rare earth ions
adsorbed on metallic surfaces is discussed.

</DOC>
<DOC>
<DOCNO> 11004 </DOCNO>
Universal behavior in the static and dynamic properties of the


  The $\alpha$-XY model generalizes, through the introduction of a power-law
decaying potential, a well studied mean-field hamiltonian model with attractive
long-range interactions. In the $\alpha$-model, the interaction between
classical rotators on a lattice is gauged by the exponent $\alpha$ in the
couplings decaying as $r^\alpha$, where $r$ are distances between sites. We
review and comment here a few recent results on the static and dynamic
properties of the $\alpha$-model. We discuss the appropriate $\alpha$ dependent
rescalings that map the canonical thermodynamics of the $\alpha$-model into
that of the mean field model. We also show that the chaotic properties of the
model, studied as a function of $\alpha$ display an universal behaviour.

</DOC>
<DOC>
<DOCNO> 118455 </DOCNO>
Kinematics of Metal-Poor Stars in the Galaxy. III. Formation of the


  (Abbreviated) We present a detailed analysis of the space motions of 1203
solar-neighborhood stars with metal abundances [Fe/H] <= -0.6, on the basis of
a recently revised and supplemented catalog of metal-poor stars selected
without kinematic bias (Beers et al. 2000). This sample, having available
proper motions, radial velocities, and distance estimates for stars with a wide
range of metal abundances, is by far the largest such catalog to be assembled
to date. Unlike essentially all previous kinematically selected catalogs, the
metal-poor stars in our sample exhibit a diverse distribution of orbital
eccentricities, e, with no apparent correlation between [Fe/H] and e. This
demonstrates, clearly and convincingly, that the evidence offered by Eggen,
Lynden-Bell, and Sandage (1962) for a rapid collapse of the Galaxy, an apparent
correlation between the orbital eccentricity of halo stars with metallicity, is
basically the result of their proper-motion selection bias. However, even in
our non-kinematically selected sample, we have identified a small concentration
of high-e stars at [Fe/H] = -1.7, which may originate, in part, from infalling
gas during the early formation of the Galaxy. The implications of our results
for the formation of the Galaxy are also discussed, in particular in the
context of the currently favored CDM theory of hierarchical galaxy formation.

</DOC>
<DOC>
<DOCNO> 70049 </DOCNO>
Check of the Bootstrap Conditions for the Gluon Reggeization


  The property of gluon Reggeization plays an essential role in the derivation
of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) equation for the cross sections at
high energy $\sqrt s$ in perturbative QCD. This property has been proved to all
orders of perturbation theory in the leading logarithmic approximation and it
is assumed to be valid also in the next-to-leading logarithmic approximation,
where it has been checked only to the first three orders of perturbation
theory. From $s$-channel unitarity, however, very stringent ``bootstrap''
conditions can be derived which, if fulfilled, leave no doubts that gluon
Reggeization holds.

</DOC>
<DOC>
<DOCNO> 117702 </DOCNO>
Emission-Line Galaxy Surveys as Probes of the Spatial Distribution of


  Objective-prism surveys which select galaxies on the basis of line-emission
are extremely effective at detecting low-luminosity galaxies and constitute
some of the deepest available samples of dwarfs. In this study, we confirm that
emission-line galaxies (ELGs) in the University of Michigan (UM)
objective-prism survey (MacAlpine et al. 1977-1981) are reliable tracers of
large-scale structure, and utilize the depth of the samples to examine the
spatial distribution of low-luminosity (M$_{B} > $ -18.0) dwarfs relative to
higher luminosity giant galaxies (M$_{B} \leq$ -18.0) in the Updated Zwicky
Catalogue (Falco et al. 1999). New spectroscopic data are presented for 26 UM
survey objects. We analyze the relative clustering properties of the overall
starbursting ELG and normal galaxy populations, using nearest neighbor and
correlation function statistics. This allows us to determine whether the
activity in ELGs is primarily caused by gravitational interactions. We conclude
that galaxy-galaxy encounters are not the sole cause of activity in ELGs since
ELGs tend to be more isolated and are more often found in the voids when
compared to their normal galaxy counterparts. Furthermore, statistical analyses
performed on low-luminosity dwarf ELGs show that the dwarfs are less clustered
when compared to their non-active giant neighbors. The UM dwarf samples have
greater percentages of nearest neighbor separations at large values and lower
correlation function amplitudes relative to the UZC giant galaxy samples. These
results are consistent with the expectations of galaxy biasing.

</DOC>
<DOC>
<DOCNO> 122479 </DOCNO>
Implications of 21cm observations for damped Ly-$\alpha$ systems


  We present Giant Metrewave Radio Telescope HI 21cm absorption observations,
of candidate and confirmed damped Lyman-$\alpha$ systems (DLAS). The derived
spin temperatures (T_s) are in all cases $\sim 1000$ K or higher. We have also
collated from the literature a list of DLAS for which 21cm observations exist,
and discuss their implications for the nature of the absorbers.
  A cross-comparison of the 21cm profiles with low ionization metal profiles
shows that the 21cm absorption coincides in velocity with the deepest metal
line feature. This is consistent with models in which the deep metal line
features arise from discrete clouds but not with models where the deepest
features are the result of velocity crowding.
  We also find that the typical derived spin temperatures of DLAS are
considerably higher than those in the Galaxy or nearby spirals. The only
exceptions are DLAS which are known to be associated with the disks of spirals;
these do, in fact, show low spin temperatures. In a multi-phase medium,the
derived T_s is a weighted average of the temperatures of the individual phases.
High derived T_s values are hence to be expected from small, low metallicity
objects, since these objects should have a lower fraction of the cold phase in
their ISM as compared to large galaxies. The high T_s in DLAS is hence
consistent with their observed low metallicities as well as with recent
observations that DLAS are also associated with dwarf/LSB galaxies. Finally, we
suggest that the following trend may be identified: at low redshift, damped
absorption arises from a range of systems, including spiral galaxy disks,
while, at high redshift, absorption occurs predominantly in smaller systems.
(Abridged)

</DOC>
<DOC>
<DOCNO> 102598 </DOCNO>
Isomorphism classes and automorphism groups of algebras of Weyl type


  In one of our recent papers, the associative and the Lie algebras of Weyl
type $A[D]=A\otimes F[D]$ were defined and studied, where $A$ is a commutative
associative algebra with an identity element over a field $F$ of any
characteristic, and $F[D]$ is the polynomial algebra of a commutative
derivation subalgebra $D$ of $A$. In the present paper, a class of the above
associative and Lie algebras $A[D]$ with $F$ being a field of characteristic 0,
$D$ consisting of locally finite but not locally nilpotent derivations of $A$,
are studied. The isomorphism classes and automorphism groups of these
associative and Lie algebras are determined.

</DOC>
<DOC>
<DOCNO> 11156 </DOCNO>
Discrete aqueous solvent effects and possible attractive forces


  We study discrete solvent effects on the interaction of two parallel charged
surfaces in ionic aqueous solution. These effects are taken into account by
adding a bilinear non-local term to the free energy of Poisson-Boltzmann
theory. We study numerically the density profile of ions between the two
plates, and the resulting inter-plate pressure. At large plate separations the
two plates are decoupled and the ion distribution can be characterized by an
effective Poisson-Boltzmann charge that is smaller than the nominal charge. The
pressure is thus reduced relative to Poisson-Boltzmann predictions. At plate
separations below ~2 nm the pressure is modified considerably, due to the
solvent mediated short-range attraction between ions in the the system. For
high surface charges this contribution can overcome the mean-field repulsion
giving rise to a net attraction between the plates.

</DOC>
<DOC>
<DOCNO> 121229 </DOCNO>
Results from the AMANDA High Energy Neutrino Detector


  This paper briefly summarizes the search for astronomical sources of
high-energy neutrinos using the AMANDA-B10 detector. The complete data set from
1997 was analyzed. For E_mu>10 TeV, the detector exceeds 10,000 m^2 in
effective area between declinations of 25 and 90 degrees. Neutrinos generated
in the atmosphere by cosmic ray interactions were used to verify the overall
sensitivity of the detector. The absolute pointing accuracy and angular
resolution has been confirmed by the analysis of coincident events between the
SPASE air shower array and the AMANDA detector. Preliminary flux limits from
point source candidates are presented. For declinations larger than +45
degrees, our results compare favorably to existing limits for sources in the
Southern sky. We also present the current status of the searches for high
energy neutrino emission from diffusely distributed sources, GRBs, and WIMPs
from the center of the earth.

</DOC>
<DOC>
<DOCNO> 85157 </DOCNO>
Inertial mass and the quantum vacuum fields


  Even when the Higgs particle is finally detected, it will continue to be a
legitimate question to ask whether the inertia of matter as a reaction force
opposing acceleration is an intrinsic or extrinsic property of matter. General
relativity specifies which geodesic path a free particle will follow, but
geometrodynamics has no mechanism for generating a reaction force for deviation
from geodesic motion. We discuss a different approach involving the
electromagnetic zero-point field (ZPF) of the quantum vacuum. It has been found
that certain asymmetries arise in the ZPF as perceived from an accelerating
reference frame. In such a frame the Poynting vector and momentum flux of the
ZPF become non-zero. Scattering of this quantum radiation by the quarks and
electrons in matter can result in an acceleration-dependent reaction force.
Both the ordinary and the relativistic forms of Newton's second law, the
equation of motion, can be derived from the electrodynamics of such
ZPF-particle interactions. Conjectural arguments are given why this interaction
should take place in a resonance at the Compton frequency, and how this could
simultaneously provide a physical basis for the de Broglie wavelength of a
moving particle. This affords a suggestive perspective on a deep connection
between electrodynamics, the origin of inertia and the quantum wave nature of
matter.

</DOC>
<DOC>
<DOCNO> 152191 </DOCNO>
Open Strings, Holography and Stochastic Processes


  We use the correspondence between string states and local operators on the
world-sheet boundary defined by vertex operators in open string theory to put
in correspondence, holographically, the bosonic open string with the large N
limit of a mechanical system living on the world-sheet boundary. We give a
natural interpretation of this system in terms of a one-dimensional stochastic
process and show that the correspondence takes the form of a map between two
conformal field theories with central charge c=24 and c=1.

</DOC>
<DOC>
<DOCNO> 116258 </DOCNO>
Statistical mechanics of neocortical interactions: Training and testing


  A series of papers has developed a statistical mechanics of neocortical
interactions (SMNI), deriving aggregate behavior of experimentally observed
columns of neurons from statistical electrical-chemical properties of synaptic
interactions. While not useful to yield insights at the single neuron level,
SMNI has demonstrated its capability in describing large-scale properties of
short-term memory and electroencephalographic (EEG) systematics. The necessity
of including nonlinear and stochastic structures in this development has been
stressed. Sets of EEG and evoked potential data were fit, collected to
investigate genetic predispositions to alcoholism and to extract brain
signatures of short-term memory. Adaptive Simulated Annealing (ASA), a global
optimization algorithm, was used to perform maximum likelihood fits of
Lagrangians defined by path integrals of multivariate conditional
probabilities. Canonical momenta indicators (CMI) are thereby derived for
individual's EEG data. The CMI give better signal recognition than the raw
data, and can be used to advantage as correlates of behavioral states. These
results give strong quantitative support for an accurate intuitive picture,
portraying neocortical interactions as having common algebraic or physics
mechanisms that scale across quite disparate spatial scales and functional or
behavioral phenomena, i.e., describing interactions among neurons, columns of
neurons, and regional masses of neurons. This paper adds to these previous
investigations two important aspects, a description of how the CMI may be used
in source localization, and calculations using previously ASA-fitted parameters
in out-of-sample data.

</DOC>
<DOC>
<DOCNO> 10147 </DOCNO>
Peak effect in CeRu$_2$:history dependence and supercooling


  We present experimental results on single crystal CeRu$_2$ showing that the
extent of history dependence of peak-effect depends on the path followed in the
space of field (H) and temperature (T). The (H,T) regime over which history
effect is observed is larger if the vortex lattice is prepared by lowering T
from above T$_C$ in constant H i.e. by field cooling. We compare this history
effect with the very recently reported history dependence of peak-effect in
detwinned single crystals of YBaCuO, highlighting the similarities and
differences. We discuss the possibility of a first order vortex solid-solid
transition in CeRu$_2$ within the realm of recent theoretical developments in
the field of vortex matter.

</DOC>
<DOC>
<DOCNO> 68131 </DOCNO>
Gravitational forces from Bose-Einstein condensation


  The basic idea that gravity can be a long-wavelength effect {\it induced} by
the peculiar ground state of an underlying quantum field theory leads to
consider the implications of spontaneous symmetry breaking through an
elementary scalar field. We point out that Bose-Einstein condensation implies
the existence of long-range order and of a gap-less mode of the (singlet)
Higgs-field. This gives rise to a $1/r$ potential and couples with
infinitesimal strength to the inertial mass of known particles. If this is
interpreted as the origin of Newtonian gravity one finds a natural solution of
the hierarchy problem. As in any theory incorporating the Equivalence
Principle, the classical tests in weak gravitational fields are fulfilled as in
general relativity. On the other hand, our picture suggests that Einstein
general relativity may represent the weak field approximation of a theory
generated from flat space with a sequence of conformal transformations. This
explains naturally the absence of a {\it large} cosmological constant from
symmetry breaking. Finally, one also predicts new phenomena that have no
counterpart in Einstein theory such as typical `fifth force' deviations below
the centimeter scale or further modifications at distances $10^{17}$ cm in
connection with the Pioneer anomaly and the mass discrepancy in galactic
systems.

</DOC>
<DOC>
<DOCNO> 151225 </DOCNO>
Vacuum Polarization Using Quantum Mechanical Path Integrals


  We compute the quantum vacuum polarization for a pure neutral scalar field
theory within the context of single-particle quantum mechanics. The loop
diagram is computed without ever encountering loop-momentum integrals. Our
approach is based on standard Feynman path integrals. Contact is made to scalar
QED.

</DOC>
<DOC>
<DOCNO> 12255 </DOCNO>
Scaling of the magnetoconductivity of silicon MOSFET's: evidence for a


  For a broad range of electron densities $n$ and temperatures $T$, the
in-plane magnetoconductivity of the two-dimensional system of electrons in
silicon MOSFET's can be scaled onto a universal curve with a single parameter
$H_{\sigma}(n,T)$, where $H_{\sigma}$ obeys the empirical relation
$H_{\sigma}=A (n) [\Delta(n)^2 +T^2]^{1/2}$. The characteristic energy $k_B
\Delta$ associated with the magnetic field dependence of the conductivity
decreases with decreasing density, and extrapolates to 0 at a critical density
$n_0$, signaling the approach to a zero-temperature quantum phase transition.
We show that $H_{\sigma}=AT$ for densities near $n_0$.

</DOC>
<DOC>
<DOCNO> 122988 </DOCNO>
Self-Interacting Cold Dark Matter Halos


  The evolution of halos consisting of weakly self-interacting dark matter
particles is summarized. The halos initially contain a central density cusp as
predicted by cosmological models. Weak self-interaction leads to the formation
of an isothermal, low-density core which is in agreement with published data on
the rotation curves of dwarf galaxies. However, subsequently, core collapse
leads to an even steeper central density cusp. In order to explain the observed
dark matter rotation curves by weak interaction, the cross section must be in a
narrow range around sigma/mp= 0.1 cm*cm/g.

</DOC>
<DOC>
<DOCNO> 119730 </DOCNO>
delta-invariant for Quasi-periodic Oscillations and Physical Parameters


  The recently formulated Two Oscillator (TO) model interprets the lowest of
the kilohertz frequencies of the twin peak quasi-periodic oscillations in X
-ray binaries as the Keplerian frequency nu_K. The high twin frequency nu_h in
this model holds the upper hybrid frequency relation to the rotational
frequency of the neutron star's magnetosphere Omega: nu_h^2=nu_K^2+
4(Omega/2pi)^2. The vector Omega is assumed to have an angle delta with the
normal to the disk. The first oscillator in the TO model allows one to
interpret the horizontal branch observed below 100 Hz as the lower mode of the
Keplerian oscillator under the influence of the Coriolis force, with frequency
nu_L being dependent on nu_h, nu_K and delta. For some stars such as 4U
0614+09, Sco X-1 and 4U 1702-42, nu_h, nu_K and nu_L have been observed
simultaneously providing the opportunity to check the central prediction of the
TO model: the constancy of delta for a particular source. Given the
considerable variation of each of these three frequencies, the existence of an
observational invariant with a clear physical interpretation as a global
parameter of the neutron star magnetosphere is an important test of the TO
model. Using the results of recent observations of 4U 0614+09 we verify the
existence of this invariant and determine the angle delta=15^o.6+/- 0.^o5 for
this star. The second oscillator in the model deals with a radial (presumably
sound) oscillation and diffuse process in the viscous layer surrounding the
neutron star. Our analysis of the viscous oscillation frequency nu_V and the
break frequency nu_b of the diffusion shows that the spin value of the inner
boundary of the transition layer for 4U 0614+09 is at least two times more than
values for 4U 1728-34 and Sco X-1.

</DOC>
<DOC>
<DOCNO> 151184 </DOCNO>
Loop dynamics and AdS/CFT correspondence


  We consider the strong coupling limit of conformal gauge theories in 4
dimensions. The action of the loop operator on the minimal area in the AdS
space is analyzed, and the Schwinger-Dyson equations of gauge theory are
checked. The general approach to the loop dynamics developed here goes beyond
the special case of conformal theories.

</DOC>
<DOC>
<DOCNO> 121047 </DOCNO>
Some Consequences of Magnetic Fields in High Energy Sources


  Magnetic fields likely play a fundamental intermediary role between gravity
and radiation in many astrophysical rotators. They can, among other things, 1)
induce and be amplified by turbulence, 2) energize coronae, 3) launch and
collimate outflows in ``spring'' or ``fling'' mechanisms. The first is widely
recognized to be important for angular momentum transport, but can also produce
intrinsic variability and possibly vorticity growth. The second leads to the
production of high energy flares, and also facilitates a test of general
relativity from AGN observations. The third can operate from rotators with a
large scale fields, though the origin of the requisite large scale fields is
somewhat unresolved. I discuss these three points in more detail below,
emphasizing some open questions.

</DOC>
<DOC>
<DOCNO> 151582 </DOCNO>
Metastability of Spherical Membranes in Supermembrane and Matrix Theory


  Motivated by recent work we study rotating ellipsoidal membranes in the
framework of the light-cone supermembrane theory. We investigate stability
properties of these classical solutions which are important for the
quantization of super membranes. We find the stability modes for all sectors of
small multipole deformations. We exhibit an isomorphism of the linearized
membrane equation with that of the SU(N) matrix model for every value of $N$.
The boundaries of the linearized stability region are at a finite distance and
they appear for finite size perturbations.

</DOC>
<DOC>
<DOCNO> 11419 </DOCNO>
Finite-wavevector phonon coupling to degenerate electronic states in


  We consider finite-k electron-phonon coupling appropriate for a
superconductor with a very short coherence length and local intersite pairs.
  From group theoretical analyis we find that phonons with nonzero k can couple
to degenerate electronic states in LaSrCuO and a Jahn-Teller-like distortion is
found to be operative for E_u and E_g -symmetry O states. Experimentally
observed anomalies in inelastic neutron scattering, ESR and EXAFS are found to
be consistent with such an interaction of the tau_1 symmetry Sigma point mode
with the planar O p_x and p_y states. The proposed interaction is found to
naturally facilitate symmetry breaking associated with pairing and/or stripe
formation.

</DOC>
<DOC>
<DOCNO> 8717 </DOCNO>
Low thermal conductivity of the layered oxide (Na,Ca)Co_2O_4: Another


  The thermal conductivity of polycrystalline samples of (Na,Ca)Co_2O_4 is
found to be unusually low, 20 mW/cmK at 280 K. On the assumption of the
Wiedemann-Franz law, the lattice thermal conductivity is estimated to be 18
mW/cmK at 280 K, and it does not change appreciably with the substitution of Ca
for Na. A quantitative analysis has revealed that the phonon mean free path is
comparable with the lattice parameters, where the point-defect scattering plays
an important role. Electronically the same samples show a metallic conduction
down to 4.2 K, which strongly suggests that NaCo_2O_4 exhibits a glass-like
poor thermal conduction together with a metal-like good electrical conduction.
The present study further suggests that a strongly correlated system with
layered structure can act as a material of a phonon glass and an electron
crystal.

</DOC>
<DOC>
<DOCNO> 122171 </DOCNO>
Bipolar outflows in OH/IR stars


  We investigate the development of bipolar outflows during the early post-AGB
evolution. A sample of ten OH/IR stars is observed at high angular resolution,
including bipolar nebulae (OH231.8+4.2), bright post-AGB stars (HD 101584) and
reflection nebulae (e.g. Roberts 22). The IRAS colour--colour diagram separates
the sample into different types of objects. One group may contain the
progenitors to the (few) extreme bipolar planetary nebulae. Two objects show
colours and chemistry very similar to the planetary nebulae with late IR-[WC]
stars. One object is a confirmed close binary.
 A model is presented consisting of an outer AGB wind which is swept up by a
faster post-AGB wind, with either wind being non-spherically symetric. The
interface of the two winds is shown to exhibit a linear relation between
velocity and distance from the star. The OH data confirms the predicted linear
velocity gradients, and reveals torus-like, uniformly expanding components. All
sources are discussed in detail using optical/HST images where available. ISO
data for Roberts 22 reveal a chemical dichotomy, with both crystalline
silicates and PAHs features being present. IRAS 16342-3814 shows a dense torus;
HST data shows four point-like sources located symmetrically around the nebula,
near the outer edge of the dense torus.
 Lifetimes for the bipolar OH/IR stars are shown to be in excess of 10^4 yr,
longer than normal post-AGB timescales. This suggests that the disks are
near-stationary. We suggest that accretion from such a disk slows down the
post-AGB evolution. Such a process could explain the link between the
long-lived bipolar nebular geometry and the retarded star.

</DOC>
<DOC>
<DOCNO> 99303 </DOCNO>
Foliations with Transversal Quaternionic Structures


  We consider manifolds equipped with a foliation $\cal F$ of codimension $4q$,
and an almost quaternionic structure $Q$ on the transversal bundle of ${\cal
F}$. After discussing conditions of projectability and integrability of $Q$, we
study the transversal twistor space $Z{\cal F}$ which, by definition, consists
of the $Q$-compatible almost complex structures. We show that $Z{\cal F}$ can
be endowed with a lifted foliation ${\hat {\cal F}}$ and two natural almost
complex structures $J_1$, $J_2$ on the transversal bundle of $\hat{\cal F}$. We
establish the conditions which ensure the projectability of $J_1$ and $J_2$,
and the integrability of $J_{1}$ ($J_{2}$ is never integrable).

</DOC>
<DOC>
<DOCNO> 118835 </DOCNO>
Propagation of ultra-high energy protons in the nearby universe


  We present a new calculation of the propagation of protons with energies
above $10^{19}$ eV over distances of up to several hundred Mpc. The calculation
is based on a Monte Carlo approach using the event generator
 SOPHIA for the simulation of hadronic nucleon-photon interactions and a
realistic integration of the particle trajectories in a random extragalactic
magnetic field. Accounting for the proton scattering in the magnetic field
affects noticeably the nucleon energy as a function of the distance to their
source and allows us to give realistic predictions on arrival energy, time
delay, and arrival angle distributions and correlations as well as secondary
particle production spectra.

</DOC>
<DOC>
<DOCNO> 119836 </DOCNO>
A Model of Metallicity Evolution in the Early Universe


  We apply the phenomenological model used to explain the abundances of Fe and
r-process elements in very metal-poor stars in the Galaxy to [Fe/H] of damped
Ly alpha systems. It is assumed that the first stars formed after the Big Bang
were very massive and promptly enriched the interstellar medium to [Fe/H] ~ -3,
at which metallicity formation of normal stars took over. Subsequent Fe
enrichment was provided by Type II supernovae. The range of [Fe/H] at a given
redshift z for damped Ly alpha systems is explained by the time t* after the
Big Bang at which normal star formation started in an individual protogalactic
system. The average t* is approx 80% the age of the universe for damped Ly
alpha systems at z approx 1.5 to 4.5, indicating a long delay between the Big
Bang and the turn-on of protogalaxies. It is inferred that a substantial
fraction of the total baryonic matter may not have been aggregated into
protogalaxies where normal star formation had occurred down to z ~ 1.5. The
data near z = 2.2 suggest that the rate of turn-on of protogalaxies was
initially very low and slowly reached a maximum at ~ 3 Gyr after the Big Bang.
This may be important in understanding the rate of formation of quasars.

</DOC>
<DOC>
<DOCNO> 71237 </DOCNO>
Two-loop QCD corrections to the scattering of massless distinct quarks


  We present the two-loop virtual QCD corrections to the scattering of massless
distinct quarks in conventional dimensional regularisation. The structure of
the infrared divergences agrees with that predicted by Catani while expressions
for the finite remainder are given for each of the s-, t- and u-channels in
terms of polylogarithms. The results presented here form a vital part of the
next-to-next-to-leading order contribution to inclusive jet production in
hadron colliders and will play a crucial role in improving the theoretical
prediction for jet cross sections in hadron-hadron collisions.

</DOC>
<DOC>
<DOCNO> 67741 </DOCNO>
Large-angle Bhabha scattering and luminosity at Daphne


  The accurate knowledge of luminosity at e^+ e^- flavour factories requires
the precision calculation of the Bhabha cross section at large scattering
angles. In order to achieve a theoretical accuracy at the 0.1% level, the
relevant effect of QED radiative corrections is taken into account in the
framework of the Parton Shower method, which allows exclusive event generation.
On this scheme, a Monte Carlo event generator (BABAYAGA) is developed for data
analysis. To test the reliability of the approach, a benchmark calculation,
including exact O(alpha) corrections and higher-order leading logarithmic
contributions, is developed as well, implemented in a Monte Carlo integrator
(LABSPV) and compared in detail with the BABAYAGA predictions. The effect of
initial-state and final-state radiation, O(alpha) next-to-leading and
higher-order leading corrections is investigated and discussed in the presence
of realistic event selections. The theoretical precision of BABAYAGA is
estimated to be at the 0.5% level.

</DOC>
<DOC>
<DOCNO> 169979 </DOCNO>
Heating of trapped particles close to surfaces - Blackbody and beyond


  We discuss heating and decoherence in traps for ions and neutral particles
close to metallic surfaces. We focus on simple trap geometries and compute
noise spectra of thermally excited electromagnetic fields. If the trap is
located in the near field of the substrate, the field fluctuations are largely
increased compared to the level of the blackbody field, leading to much shorter
coherence and life times of the trapped atoms. The corresponding time constants
are computed for ion traps and magnetic traps. Analytical estimates for the
size dependence of the noise spectrum are given. We finally discuss prospects
for the coherent transport of matter waves in integrated surface waveguides.

</DOC>
<DOC>
<DOCNO> 118946 </DOCNO>
Cosmological Constraints from the Cosmic Microwave Background


  Using an approximate likelihood method adapted to band--power estimates, we
analyze the ensemble of first generation cosmic microwave background anisotropy
experiments to deduce constraints over a six--dimensional parameter space
describing Inflation--generated adiabatic, scalar fluctuations. The basic
preferences of simple Inflation scenarios are consistent with the data set:
flat geometries $(\OmT \equiv 1-\Omk \sim 1)$ and a scale--invariant primeval
spectrum ($n\sim 1$) are favored. Models with significant negative curvature
($\OmT < 0.7$) are eliminated, while constraints on postive curvature are less
stringent. Degeneracies among the parameters prevent independent determinations
of the matter density $\OmM$ and the cosmological constant $\Lambda$, and the
Hubble constant $\Ho$ remains relatively unconstrained. We also find that the
height of the first Doppler peak relative to the amplitude suggested by data at
larger $l$ indicates a high baryon content ($\Omb h^2$), almost independently
of the other parameters. Besides the overall qualitative advance expected of
the next generation experiments, their improved dipole calibrations will be
particularly useful for constraining the peak height. Our analysis includes a
{\em Goodness--of--Fit} statistic applicable to power estimates and which
indicates that the maximum likelihood model provides an acceptable fit to the
data set.

</DOC>
<DOC>
<DOCNO> 72254 </DOCNO>
S-matrix Bases and Relation between pi pi Scattering and Production


  It is stated that the requirement of unitarity and of analyticity should be
made on the S-matrix elements with right bases, and the ``universality
argument" made with the bases, which do not regard quark physical picture, is
not right. Accordingly the result of the conventional analyses of the pi pi
production amplitudes following to this argument, leading to non-existence of
the light sigma-meson, is proved to lose its theoretical bases.

</DOC>
<DOC>
<DOCNO> 84712 </DOCNO>
Hawking Radiation from AdS Black Holes


  We investigate Hawking radiation from black holes in (d+1)-dimensional
anti-de Sitter space. We focus on s-waves, make use of the geometrical optics
approximation, and follow three approaches to analyze the radiation. First, we
compute a Bogoliubov transformation between Kruskal and asymptotic coordinates
and compare the different vacua. Second, following a method due to Kraus,
Parikh, and Wilczek, we view Hawking radiation as a tunneling process across
the horizon and compute the tunneling probablility. This approach uses an
anti-de Sitter version of a metric originally introduced by Painleve for
Schwarzschild black holes. From the tunneling probability one also finds a
leading correction to the semi-classical emission rate arising from the
backreaction to the background geometry. Finally, we consider a spherically
symmetric collapse geometry and the Bogoliubov transformation between the
initial vacuum state and the vacuum of an asymptotic observer.

</DOC>
<DOC>
<DOCNO> 121835 </DOCNO>
A Binary Millisecond Pulsar in Globular Cluster NGC6544


  We report the detection of a new 3.06 ms binary pulsar in the globular
cluster NGC6544 using a Fourier-domain ``acceleration'' search. With an implied
companion mass of ~0.01 solar masses and an orbital period of only P_b~1.7
hours, it displays very similar orbital properties to many pulsars which are
eclipsed by their companion winds. The orbital period is the second shortest of
known binary pulsars after 47 Tuc R. The measured flux density of 1.3 +/- 0.4
mJy at 1332 MHz indicates that the pulsar is almost certainly the known
steep-spectrum point source near the core of NGC6544.

</DOC>
<DOC>
<DOCNO> 85451 </DOCNO>
On the scalar sector of the covariant graviton two-point function in de


  We examine the scalar sector of the covariant graviton two-point function in
de Sitter spacetime. This sector consists of the pure-trace part and another
part described by a scalar field. We show that it does not contribute to
two-point functions of gauge-invariant quantities. We also demonstrate that the
long-distance growth present in some gauges is absent in this sector for a wide
range of gauge parameters.

</DOC>
<DOC>
<DOCNO> 117446 </DOCNO>
Luminosities, Space Densities and Redshift Distributions of Gamma-Ray


  We use the BD2 sample of gamma-ray bursts (GRBs) based on 5.9 years of BATSE
DISCLA data with a variety of models of the luminosity function to derive
characteristic GRB luminosities, space densities and redshift distributions.
Previously published results for an open universe and modest density evolution
of the GRBs showed characteristic peak luminosities around 5x10**51 erg/s in
the 50-300 keV band if the emission is isotropic, and local space densities
around 0.2 Gpc**-3 yr**-1. In this paper, we illustrate for several luminosity
function models the predicted distributions of peak flux, luminosity and
redshifts. We use the luminosity function models also to address the connection
between supernovae and GRB. If all supernovae of Type Ib/c harbor a GRB, the
beaming fraction would have to be 10**-5 - 10**-3.5. We find that GRB 980425,
if correctly identified with SN 1998bw, has to be part of a population
different from that of the bulk of GRBs.

</DOC>
<DOC>
<DOCNO> 14109 </DOCNO>
Probing the energy bands of a Bose-Einstein condensate in an optical


  We simulate three experimental methods which could be realized in the
laboratory to probe the band excitation energies and the momentum distribution
of a Bose-Einstein condensate inside an optical lattice. The values of the
excitation energies obtained in these different methods agree within the
accuracy of the simulation. The meaning of the results in terms of density and
phase deformations is tested by studying the relaxation of a phase-modulated
condensate towards the ground state.

</DOC>
<DOC>
<DOCNO> 170396 </DOCNO>
Decomposition of Hilbert space in sets of coherent states


  Within the generalized definition of coherent states as group orbits we study
the orbit spaces and the orbit manifolds in the projective spaces constructed
from linear representations. Invariant functions are suggested for arbitrary
groups. The group SU(2) is studied in particular and the orbit spaces of its
j=1/2 and j=1 representations completely determined. The orbits of SU(2) in
CP^N can be either 2 or 3 dimensional, the first of them being either
isomorphic to S^2 or to RP^2 and the latter being isomorphic to quotient spaces
of RP^3. We end with a look from the same perspective to the quantum mechanical
space of states in particle mechanics.

</DOC>
<DOC>
<DOCNO> 10069 </DOCNO>
Self-dual Ginzburg-Landau vortices in a disk


  We study the properties of the Ginzburg-Laundau model in the self-dual point
for a two-dimensional finite system . By a numerical calculation we analyze the
solutions of the Euler-Lagrange equations for a cylindrically symmetric ansatz.
We also study the self-dual equations for this case. We find that the minimal
energy configurations are not given by the Bogomol'nyi equations but by
solutions to the Euler Lagrange ones. With a simple approximation scheme we
reproduce the result of the numerical calculation.

</DOC>
<DOC>
<DOCNO> 117546 </DOCNO>
Ages, Distances, and the Initial Mass Functions of Stellar Clusters


  We provide a review of the current status of several topics on the ages,
distances, and mass functions of open clusters, with a particular emphasis on
illuminating the areas of uncertainty. Hipparcos has obtained parallaxes for
nearby open clusters that have expected accuracies much better than has been
previously achievable. By using the lithium depletion boundary method and
isochrone fitting based on much improved new theoretical evolutionary models
for low mass stars, it is arguable that we will soon have have much better age
scales for clusters and star-forming regions. With improved optical and near-IR
cameras, we are just now beginning to extend the mass function of open clusters
like the Pleiades into the regime below the hydrogen burning mass limit.
Meanwhile, observations in star-forming regions are in principle capable of
identifying objects down to of order 10 Jupiter masses.

</DOC>
<DOC>
<DOCNO> 9574 </DOCNO>
A class of N-body problems with nearest- and next-to-nearest neighbour


  We obtain the exact ground state and a part of the excitation spectrum in one
dimension on a line and the exact ground state on a circle in a case where N
particles are interacting via nearest- and next-to-nearest neighbour
interactions. Further, using the exact ground-state, we establish a mapping
between these N-body problems and the short-range Dyson models introduced
recently to model intermediate spectral statistics. Using this mapping we
compute the one- and two-point functions of a related many-body theory and show
that there is no long-range order in the thermodynamic limit. However, quite
remarkably, we prove the existence of an off-diagonal long-range order in the
symmetrised version of the related many-body theory. Generalisation of the
models to other root systems is also considered. Besides, we also generalize
the model on the full line to higher dimensions. Finally, we consider a model
in two dimensions in which all the states exhibit novel correlations.

</DOC>
<DOC>
<DOCNO> 117666 </DOCNO>
New Constraints from High Redshift Supernovae and Lensing Statistics


  We explore the implications of gravitationally lensed QSOs and high-redshift
SNe Ia observations for spatially flat cosmological models in which a
classically evolving scalar field currently dominates the energy density of the
Universe. We consider two representative scalar field potentials that give rise
to effective decaying $\Lambda $ (``quintessence'') models:
pseudo-Nambu-Goldstone bosons ($V(\phi)=M^4(1+\cos (\phi /f)) $) and an inverse
power-law potential ($V(\phi)=M^{4+\alpha}\phi ^{-\alpha}$). We show that a
large region of parameter space is consistent with current data if $\Omega_{m0}
> 0.15$. On the other hand, a higher lower bound for the matter density
parameter suggested by large-scale galaxy flows, $\Omega_{m0} > 0.3$,
considerably reduces the allowed parameter space, forcing the scalar field
behavior to approach that of a cosmological constant.

</DOC>
<DOC>
<DOCNO> 169867 </DOCNO>
Renormalization Group at finite temperature in Quantum Mechanics


  We establish the exact renormalization group equation for the potential of a
one quantum particle system at finite and zero temperature. As an example we
use it to compute the ground state energy of the anharmonic oscillator. We
comment on an improvement of the Feynman Kleinert's variational method by the
renormalization group.

</DOC>
<DOC>
<DOCNO> 170098 </DOCNO>
Are Interaction-free Measurements Interaction Free?


  In 1993 Elitzur and Vaidman introduced the concept of interaction-free
measurements which allowed finding objects without ``touching'' them. In the
proposed method, since the objects were not touched even by photons, thus, the
interaction-free measurements can be called as ``seeing in the dark''. Since
then several experiments have been successfully performed and various
modifications were suggested. Recently, however, the validity of the term
``interaction-free'' has been questioned. The criticism of the name is briefly
reviewed and the meaning of the interaction-free measurements is clarified.

</DOC>
<DOC>
<DOCNO> 150823 </DOCNO>
Magnetic and Dyonic Black Holes in D=4 Gauged Supergravity


  Magnetic and Dyonic solutions are constructed for the theory of abelian
gauged N=2 gauged four dimensional supergravity coupled to vector multiplets.
The solutions found preserve 1/4 of the supersymmetry.

</DOC>
<DOC>
<DOCNO> 10696 </DOCNO>
Extremal Optimization: Heuristics via Co-Evolutionary Avalanches


  An introduction to Extremal Optimization written for the Computer Simulation
Column in ``Computing in Science and Engineering'' (CISE).

</DOC>
<DOC>
<DOCNO> 13917 </DOCNO>
Renormalization-group study of gate charge effects in Josephson-junction


  We study the quantum phase transition in a chain of superconducting grains,
coupled by Josephson junctions, with emphasis on the effects of gate charges
induced on the grains. At zero temperature the system is mapped onto a
two-dimensional classical Coulomb gas, where the gate charge plays the role of
an imaginary electric field. Such a field is found relevant in the
renormalization-group transformation and to change the nature of the
superconductor-insulator transition present in the system, tending to suppress
quantum fluctuations and helping establish superconductivity. On the basis of
this observation, we propose the zero-temperature phase diagram on the plane of
the gate charge and the energy ratio.

</DOC>
<DOC>
<DOCNO> 169755 </DOCNO>
Factoring the unitary evolution operator and quantifying entanglement


  The unitary evolution can be represented by a finite product of exponential
operators. It leads to a perturbative expression of the density operator of a
close system. Based on the perturbative expression scheme, we present a
entanglement measure, this measure has the advantage that it is easy to compute
for a general dynamical process.

</DOC>
<DOC>
<DOCNO> 71267 </DOCNO>
Classical Order Parameter Dynamics and the Decay of a Metastable Vacuum


  Transition of the ground state of a classical $\Phi^4$ theory in 2+1
dimensions is studied from a metastable state into the stable equilibrium. The
transition occurs in the broken $Z_2$ symmetry phase and is triggered by a
vanishingly small amplitude homogeneous external field $h$. A phenomenological
theory is proposed in form of an effective equation of the quantitatively
accounts for the decay of the false vacuum. The large amplitude transition of
the order parameter between the two minima displays characteristics reflecting
dynamical aspects of the Maxwell construction.

</DOC>
<DOC>
<DOCNO> 122654 </DOCNO>
XMM-Newton survey of the low-metallicity open cluster NGC 2516


  We present the first results of an XMM-Newton EPIC survey of NGC 2516, a
southern low-metallicity open cluster with an age close to the Pleiades. The
attained limiting sensitivity is of ~ 2.4 10^-15 erg sec^-1} cm^-2 in the
0.1--4.0 keV bandpass. This has been achieved by summing the data of the MOS
and PN cameras of two distinct observations for a total exposure time of ~ 33
ks and by analyzing the summed data set with the wavelet detection algorithm
developed at Osservatorio Astronomico di Palermo (OAPA) that has yielded over
200 X-ray detections. Using data just from a single exposure or from a single
camera would have reduced by a factor 2--4 our limiting sensitivity and would
have resulted in 25--40% less X-ray detections. To date, 129 detections have as
counterparts one or more of the 540 photometrically selected cluster members in
the surveyed region, for a total of 147 likely detected members, with unique
identification in 112 cases. We derive the X-ray luminosity functions (XLF) of
NGC 2516 members of different spectral types and compare them with those of the
more metal rich, approximately coeval Pleiades cluster, finding the NGC 2516
photometrically selected dG and dK stars less luminous than the Pleiades. The
XLFs of the NGC 2516 and of the Pleiades dM stars are indistinguishable. We
compare the XMM-Newton results with those recently obtained with Chandra.

</DOC>
<DOC>
<DOCNO> 118796 </DOCNO>
High Resolution Near-Infrared Spectra of Protostars


  We present new high resolution (R = 21,000) near-infrared (2 microns)
spectroscopic observations of a sample of Class I and flat-spectrum
protostellar objects in the rho Ophiuchi dark cloud. None of the five Class I
spectra show CO v = 0 -- 2 absorption features, consistent with high K-band
continuum veilings, 4 <= r_k <= 20 and fast stellar rotation, assuming that the
underlying protostellar photospheres are of late spectral type, as is suggested
by the low luminosities of most of these objects. Two of the flat-spectrum
protostellar objects also show no absorption features and are likely to be
highly veiled. The remaining two flat-spectrum sources show weak, broad
absorptions which are consistent with an origin in quickly rotating (v sin i ~
50 km / s) late-type stellar photospheres which are also strongly veiled, r_k =
3 - 4. These observations provide further evidence that: 1)-Class I sources are
highly veiled at near-infrared wavelengths, confirming previous findings of
lower resolution spectroscopic studies; and 2)- flat-spectrum protostars rotate
more rapidly than classical T Tauri stars (Class II sources), supporting
findings from a recent high resolution spectroscopic study of other
flat-spectrum sources in this cloud. In addition our observations are
consistent with the high rotation rates derived for two of the Class I
protostellar objects in our sample from observations of variable hard X-ray
emission obtained with the ASCA satellite. These observations suggest that
certain Class I sources can rotate even more rapidly than flat-spectrum
protostars, near breakup velocity.

</DOC>
<DOC>
<DOCNO> 10683 </DOCNO>
Theories of Low-Energy Quasi-Particle States in Disordered d-Wave


  The physics of low-energy quasi-particle excitations in disordered d-wave
superconductors is a subject of ongoing intensive research. Over the last
decade, a variety of conceptually and methodologically different approaches to
the problem have been developed. Unfortunately, many of these theories
contradict each other, and the current literature displays a lack of consensus
on even the most basic physical observables. Adopting a symmetry-oriented
approach, the present paper attempts to identify the origin of the disagreement
between various previous approaches, and to develop a coherent theoretical
description of the different low-energy regimes realized in weakly disordered
d-wave superconductors. We show that, depending on the presence or absence of
time-reversal invariance and the microscopic nature of the impurities, the
system falls into one of four different symmetry classes. By employing a
field-theory formalism, we derive effective descriptions of these universal
regimes as descendants of a common parent field theory of
Wess-Zumino-Novikov-Witten type. This general formalism is then applied to an
analysis of the most controversially discussed characteristic of the disordered
system: the low-energy quasi-particle density of states (DoS). Specifically, we
compute the DoS for all four classes, analyse a number of physically relevant
crossover scenarios, and discuss reasons for the disagreement between previous
results. We also touch upon other aspects of the phenomenology of the d-wave
superconductor such as quasi-particle localization properties, the spin quantum
Hall effect, and the quasi-particle physics of the disordered vortex lattice.

</DOC>
<DOC>
<DOCNO> 119765 </DOCNO>
The Discovery of a Luminous z=5.80 Quasar from the Sloan Digital Sky


  We present observations of SDSSp J104433.04--012502.2, a luminous quasar at
z=5.80 discovered from Sloan Digital Sky Survey (SDSS) multicolor imaging data.
This object was selected as an i'-band dropout object, with i*=21.8 +/- 0.2,
z*=19.2 +/- 0.1. It has an absolute magnitude M1450 = -27.2 (H_0 =50 km/s/Mpc,
q0 = 0.5). The spectrum shows a strong and broad Ly alpha emission line, strong
Ly alpha forest absorption lines with a mean continuum decrement D_A = 0.91,
and a Lyman Limit System at z=5.72. The spectrum also shows strong OI and SiIV
emission lines similar to those of quasars at z<= 5, suggesting that these
metals were produced at redshift beyond six. The lack of a Gunn-Peterson trough
in the spectrum indicates that the universe is already highly ionized at z ~
5.8. Using a high-resolution spectrum in the Ly alpha forest region, we place a
conservative upper limit of the optical depth due to the Gunn-Peterson effect
of tau < 0.5 in regions of minimum absorption. The Ly alpha forest absorption
in this object is much stronger than that in quasars at z<= 5. The object is
unresolved in a deep image with excellent seeing, implying that it is unlensed.
The black hole mass of this quasar is ~3 x 10^9 M_solar if we assume that it is
radiating at the Eddington luminosity and no lensing amplification, implying
that it resides in a very massive dark matter halo. The discovery of one quasar
at M_1450 < -27 in a survey area of 600 deg^2 is consistent with an
extrapolation of the observed luminosity function at lower redshift. The
abundance and evolution of such quasars can provide sensitive tests of models
of quasar and galaxy formation.

</DOC>
<DOC>
<DOCNO> 151513 </DOCNO>
On the Quantization Constraints for a D3 Brane in the Geometry of NS5


  A D3 brane in the background of NS5 branes is studied semi-classically. The
conditions for preserved supersymmetry are derived, leading to a differential
equation for the shape of the D3 brane. The solutions of this equation are
analyzed. For a D3 brane intersecting the NS5 branes, the angle of approach is
known to be restricted to discrete values. Four different ways to obtain this
quantization are described. In particular, it is shown that, assuming the D3
brane avoids intersecting a {\em single} NS5 brane, the above discrete values
correspond to the different possible positions of the D3 branes among the NS5
branes.

</DOC>
<DOC>
<DOCNO> 84896 </DOCNO>
Noncommutative Quantum Gravity


  The possible role of gravity in a noncommutative geometry is investigated.
Due to the Moyal *-product of fields in noncommutative geometry, it is
necessary to complexify the metric tensor of gravity. We first consider the
possibility of a complex Hermitian, nonsymmetric $g_{\mu\nu}$ and discuss the
problems associated with such a theory. We then introduce a complex symmetric
(non-Hermitian) metric, with the associated complex connection and curvature,
as the basis of a noncommutative spacetime geometry. The spacetime coordinates
are in general complex and the group of local gauge transformations is
associated with the complex group of Lorentz transformations CSO(3,1). A real
action is chosen to obtain a consistent set of field equations. A Weyl
quantization of the metric associated with the algebra of noncommuting
coordinates is employed.

</DOC>
<DOC>
<DOCNO> 151210 </DOCNO>
The Type I D-instanton and its M-theory Origin


  The tree-level amplitude for the scattering of two gauge particles
constrained to move on the two distinct boundaries of eleven-dimensional
space-time in the Horava-Witten formulation of M-theory is constructed. At low
momenta this reproduces the corresponding tree-level scattering amplitude of
the E_8xE_8 heterotic string theory. After compactification to nine dimensions
on a large circle with a suitable Wilson line to break the symmetry to
SO(16)xSO(16) this amplitude is used to describe the scattering of two massive
SO(16) spinor states - one from each factor of the unbroken symmetry group. The
amplitude contains a component that is associated with the exchange of a
Kaluza-Klein charge between the boundaries, which is interpreted as the
exchange of a D-particle between orientifold planes in the Type IA theory. This
is related by T-duality to the effect of a non-BPS D-instanton in the Type I
theory which is only invariant under those elements of O(16)xSO(16) that are in
SO(16)xSO(16).

</DOC>
<DOC>
<DOCNO> 8249 </DOCNO>
Spin stripe dimerization in the t-J model


  In the present work we demonstrate that the spin columnar dimerized phase
(conducting spin stripe liquid) is stable at doping $x_{c1} < x < x_{c2}$. At
$x < x_{c1}$ the system undergoes phase transition to the Neel state, and at $x
> x_{c2}$ it is Normal Fermi liquid. At t/J=3 the critical concentrations are
$x_{c1}\approx 0.09$ and $x_{c2}\sim 0.36$. To prove stability of the stripe
phase and to calculate critical concentrations we employ two approaches. The
first one is more technically involved, and it gives more accurate value of the
critical concentration. The approach is based on the calculation of the magnon
Green's function. Imaginary poles in the Green's function indicate transition
to the Neel state. The second approach consists in direct comparison of ground
state energies of the Neel state and the columnar dimerized state. Both
approaches demonstrate stability of the spin stripe phase and give close values
of the critical concentrations.

</DOC>
<DOC>
<DOCNO> 69093 </DOCNO>
A Note on Large Extra Dimensions


  We study corrections to the photon-propagator in a recently proposed model,
where gravity lives in 4+n dimensions and Standard Model fields in 4
dimensions. We find a correction to the form factor of the photon that can be
constrained by QED tests.

</DOC>
<DOC>
<DOCNO> 151469 </DOCNO>
Duality and Massless Monopoles


  Duality arguments suggest the existence of massless magnetic monopoles in
gauge theories with the symmetry broken to a non-Abelian subgroup. I discuss
how these arise and show how they are manifested as clouds of massless fields
surrounding massive monopoles. The dynamics of these clouds is discussed, and
the scattering of massless monopole clouds and massive monopoles is described.

</DOC>
<DOC>
<DOCNO> 85330 </DOCNO>
Dynamical Bar Instability in Rotating Stars: Effect of General


  We study the dynamical stability against bar-mode deformation of rapidly and
differentially rotating stars in the first post-Newtonian approximation of
general relativity. We vary the compaction of the star $M/R$ (where $M$ is the
gravitational mass and $R$ the equatorial circumferential radius) between 0.01
and 0.05 to isolate the influence of relativistic gravitation on the
instability. For compactions in this moderate range, the critical value of
$\beta \equiv T/W$ for the onset of the dynamical instability (where $T$ is the
rotational kinetic energy and $W$ the gravitational binding energy) slightly
decreases from $\sim 0.26$ to $\sim 0.25$ with increasing compaction for our
choice of the differential rotational law. Combined with our earlier findings
based on simulations in full general relativity for stars with higher
compaction, we conclude that relativistic gravitation {\em enhances} the
dynamical bar-mode instability, i.e. the onset of instability sets in for
smaller values of $\beta$ in relativistic gravity than in Newtonian gravity. We
also find that once a triaxial structure forms after the bar-mode perturbation
saturates in dynamically unstable stars, the triaxial shape is maintained, at
least for several rotational periods. To check the reliability of our numerical
integrations, we verify that the general relativistic Kelvin-Helmholtz
circulation is well-conserved, in addition to rest-mass energy, total
mass-energy, linear and angular momentum. Conservation of circulation indicates
that our code is not seriously affected by numerical viscosity. We determine
the amplitude and frequency of the quasi-periodic gravitational waves emitted
during the bar formation process using the quadrupole formula.

</DOC>
<DOC>
<DOCNO> 11699 </DOCNO>
Dispersive Lineshape Theory


  Motivated by recent experiments we consider a stochastic lineshape theory for
the case when the underlying process obeys power-law statistics, based on a
generalized Anderson-Kubo oscillator model. We derive an analytical expression
for the lineshape and find rich type of behaviors when compared with the
standard theory, for example, new type of resonances and narrowing phenomena.
We show that the lineshape is extremely sensitive to the way the system is
prepared at time $t=0$ and discuss the problem of stationarity.

</DOC>
<DOC>
<DOCNO> 69863 </DOCNO>
No-Scale Scenario with Non-Universal Gaugino Masses


  Phenomenological issues of no-scale structure of K\"{a}hler potential are
re-examined, which arises in various approaches to supersymmetry breaking. When
no-scale boundary conditions are given at the Grand Unified scale and universal
gaugino masses are postulated, a bino mass is quite degenerate with
right-handed slepton masses and the requirement that the lightest superparticle
(LSP) be neutral supplemented with slepton searches at LEP200 severely
constrains allowed mass regions of superparticles. The situation drastically
changes if one moderately relaxes the assumption of the universal gaugino
masses. After reviewing some interesting scenarios where non-universal gaugino
masses arise, we show that the non-universality diminishes the otherwise severe
constraint on the superparticle masses, and leads a variety of superparticle
mass spectra: in particular the LSP can be a wino-like neutralino, a
higgsino-like neutralino, or even a sneutrino, and also left-handed sleptons
can be lighter than right-handed ones.

</DOC>
<DOC>
<DOCNO> 117986 </DOCNO>
Photographic photometries and astrophysical parameters of the open


  Photographic photometries of 789 stars in the region of the open clusters
NGC1750 and NGC1758 are derived from a set of 8 photometric plates. According
to the astronomical data including proper motions, positions and membership
probabilities of individual stars, several astrophysical parameters for these
two clusters are determined, such as HR diagrams, ages, distances, luminosity
functions, masses and kinematics, etc. It is found that the distances are
 ($525\pm 48$pc) and ($794\pm 73$pc) with ages of $1.5\times10^8$yr and
$6.3\times10^8$yr for
 NGC1750 and NGC1758 respectively. Both clusters show no significant mass
segregation effects because of their relatively young ages. The analysis of the
proper motions imply that their velocity distributions are isotropy.

</DOC>
<DOC>
<DOCNO> 118177 </DOCNO>
A phase-reference study of the quasar pair 1038+528A,B


  We present results from 3.6 cm observations of the quasar pair 1038+528 A and
B, made in 1995 using the VLBA together with the Effelsberg 100m telescope. We
describe the use of a phase-referencing technique to measure the astrometric
separation between the quasars. We also introduce a new data analysis method
-"hybrid double mapping"- which preserves the relative astrometric information
in a single VLBI hybrid map for close source pairs. We combine our measurements
with those from three previous epochs, the earliest in 1981. Our new
observations confirm the evolution within the structure of quasar B, previously
proposed to explain the measured change in the relative separation of the pair.
Our upper bound for any systematic proper motion between the mass centres of
quasars A and B is 10 micro-arcsec/year. This is set by the limited precision
in defining the reference points in the quasars at different epochs and by
possible instabilities of the source "core" locations. A separate analysis
enables us to put more stringent upper limits to any core motions along the two
source axes.

</DOC>
<DOC>
<DOCNO> 119681 </DOCNO>
Line formation in solar granulation: III. The photospheric Si and


  Using realistic hydrodynamical simulations of the solar surface convection as
3D, time-dependent, inhomogeneous model atmospheres, the solar photospheric Si
abundance has been determined to be log Si = 7.51 +- 0.04. This constitutes a
difference of 0.04 dex compared with previous estimates based on the 1D
Holweger-M\"uller (1974) model, of which half is attributable to the adopted
model atmosphere and the remaining part to the improved quantum mechanical
broadening treatment. As a consequence, all meteoritic abundances should be
adjusted downwards by the same amount. In particular the meteoritic Fe
abundance will be log Fe = 7.46 +- 0.01, in good agreement with the recently
determined photospheric Fe abundance (Asplund et al. 2000b). The existing
uncertainties unfortunately prevent an observational confirmation of the
postulated effects of elemental migration of metals in the Sun.

</DOC>
<DOC>
<DOCNO> 117218 </DOCNO>
Ideal Coinstraints - A Warning Note


  A criticism against the conception adopted by some textbook's authors
concerning ideal constraints is presented. The criticism is strengthen with two
traditional examples.

</DOC>
<DOC>
<DOCNO> 122434 </DOCNO>
A Review of Disk-Corona Oscillations


  Low frequency (approximately 0.1-35 Hz) quasi-periodic oscillations (QPO) of
the X-ray flux characterize many of the black hole candidates, in particular
those which have radio evidence for jets. These QPO have amplitudes of up to 20
per cent in the states of black hole novae which are called very high and
intermediate. The frequencies are correlated with the break frequency of the
band-limited low frequency white noise. With transition to the state called the
soft high state, both the QPO and the noise disappear. While the noise is
strong in the low hard states like that of Cyg X-1, the QPO, when present, are
weak and broad. In their strong manifestations, these QPO have the curious
property of appearing to have the spectrum of the power-law component which
dominates in the low state, while correlations between their frequency and the
disk component in the spectrum imply control by the disk. The correlations, the
harmonic structure of the QPO, and the phase lags have complex behavior in the
same source (GRS 1915+105, XTE J1550-564). The phenomena point to interaction
between the disk and the corona, for which there are several interesting ideas.

</DOC>
<DOC>
<DOCNO> 10321 </DOCNO>
Local Reorientation Dynamics of Semiflexible Polymers in the Melt


  The reorientation dynamics of local tangent vectors of chains in isotropic
amorphous melts containing semiflexible model polymers was studied by molecular
dynamics simulations. The reorientation is strongly influenced both by the
local chain stiffness and by the overall chain length. It takes place by two
different subsequent processes: A short-time non-exponential decay and a
long-time exponential reorientation arising from the relaxation of medium-size
chain segments. Both processes depend on stiffness and chain length. The strong
influence of the chain length on the chain dynamics is in marked contrast to
its negligible effect on the static structure of the melt. The local structure
shows only a small dependence on the stiffness, and is independent of chain
length. Calculated correlation functions related to double-quantum NMR
experiments are in qualitative agreement with experiments on entangled melts. A
plateau is observed in the dependence of segment reorientation on the
mean-squared displacement of the corresponding chain segments. This plateau
confirms, on one hand, the existence of reptation dynamics. On the other hand,
it shows how the reptation picture has to be adapted if, instead of fully
flexible chains, semirigid chains are considered.

</DOC>
<DOC>
<DOCNO> 40114 </DOCNO>
Studies of the Response of the Prototype CMS Hadron Calorimeter,


  We report on the response of a prototype CMS hadron calorimeter module to
charged particle beams of pions, muons, and electrons with momenta up to 375
GeV/c. The data were taken at the H2 and H4 beamlines at CERN in 1995 and 1996.
The prototype sampling calorimeter used copper absorber plates and scintillator
tiles with wavelength shifting fibers for readout. The effects of a magnetic
field of up to 3 Tesla on the response of the calorimeter to muons, electrons,
and pions are presented, and the effects of an upstream lead tungstate crystal
electromagnetic calorimeter on the linearity and energy resolution of the
combined calorimetric system to hadrons are evaluated. The results are compared
with Monte Carlo simulations and are used to optimize the choice of total
absorber depth, sampling frequency, and longitudinal readout segmentation.

</DOC>
<DOC>
<DOCNO> 100102 </DOCNO>
Relativistic wave equations with fractional derivatives and


  The class of the free relativistic covariant equations generated by the
fractional powers of the D'Alambertian operator $(\square^{1/n})$ is studied.
Meanwhile the equations corresponding to n=1 and 2 (Klein-Gordon and Dirac
equations) are local in their nature, the multicomponent equations for
arbitrary n>2 are non-local. It is shown, how the representation of generalized
algebra of Pauli and Dirac matrices looks like and how these matrices are
related to the algebra of SU(n) group. The corresponding representations of the
Poincar\'e group and further symmetry transformations on the obtained equations
are discussed. The construction of the related Green functions is suggested.

</DOC>
<DOC>
<DOCNO> 99852 </DOCNO>
Invertible knot concordances and prime knots


  Kirby and Lickorish showed that every knot in the 3-sphere is concordant to a
prime knot, equivalently, every concordance class contains a prime knot. We
prove here that their result can be strengthened: Every knot in the 3-sphere is
invertibly concordant to a prime knot. A consequence is that every double
concordance class contains a prime knot.

</DOC>
<DOC>
<DOCNO> 170605 </DOCNO>
Raman Sideband Cooling in presence of Multiple Decay Channels


  We have investigated the efficiency of pulsed Raman sideband cooling in the
presence of multiple decay and excitation channels. By applying sum rules we
identify parameter regimes in which multiple scattering of photons can be
described by an effective wave vector. Using this method we determine the rate
of heating caused by optical pumping inside and outside the Lamb-Dicke regime.
On this basis we discuss also the efficiency of a recently proposed scheme for
ground-state cooling outside the Lamb-Dicke regime [G. Morigi, J.I. Cirac, M.
Lewenstein, and P. Zoller, Europhys. Lett. {\bf 39}, 13
 (1997)].

</DOC>
<DOC>
<DOCNO> 11769 </DOCNO>
Economics Mapping to the Renormalization Group Scaling of Stock Markets


  We make an attempt to map a simple economically motivated model for the price
evolution [J. Phys. A: Gen. Math 33, 3637 (2000)] to the phenomenological
renormalization group scaling of stock markets. This mapping gives insight into
the critical exponents and the renormalization group predictions for the
log-periodic oscillations preceding some stock market crashes from the
perspective of non-linear changes in `the level of stocks'.

</DOC>
<DOC>
<DOCNO> 123097 </DOCNO>
Reddening Independent Quasar Selection from a Wide Field Optical and


  We present preliminary results from a wide field near-IR imaging survey that
uses the Cambridge InfraRed Survey Instrument (CIRSI) on the 2.5m Isaac Newton
Telescope (INT). CIRSI is a JH-band mosaic imager that contains 4 Rockwell
1024$^{2}$ HgCdTe detectors (the largest IR camera in existence), allowing us
to survey approximately 4 deg^2 per night to H ~ 19. Combining CIRSI
observations with the deep optical imaging from the INT Wide Field Survey, we
demonstrate a reddening independent quasar selection technique based on the (g
- z) / (z - H) color diagram.

</DOC>
<DOC>
<DOCNO> 150646 </DOCNO>
Mirror Symmetry


  We prove mirror symmetry for supersymmetric sigma models on Kahler manifolds
in 1+1 dimensions. The proof involves establishing the equivalence of the
gauged linear sigma model, embedded in a theory with an enlarged gauge
symmetry, with a Landau-Ginzburg theory of Toda type. Standard R -> 1/R duality
and dynamical generation of superpotential by vortices are crucial in the
derivation. This provides not only a proof of mirror symmetry in the case of
(local and global) Calabi-Yau manifolds, but also for sigma models on manifolds
with positive first Chern class, including deformations of the action by
holomorphic isometries.

</DOC>
<DOC>
<DOCNO> 13832 </DOCNO>
Hysteresis and the dynamic phase transition in thin ferromagnetic films


  Hysteresis and the non-equilibrium dynamic phase transition in thin magnetic
films subject to an oscillatory external field have been studied by Monte Carlo
simulation. The model under investigation is a classical Heisenberg spin system
with a bilinear exchange anisotropy in a planar thin film geometry with
competing surface fields. The film exhibits a non-equilibrium phase transition
between dynamically ordered and dynamically disordered phases characterized by
a critical temperature Tcd, whose location of is determined by the amplitude H0
and frequency w of the applied oscillatory field. In the presence of competing
surface fields the critical temperature of the ferromagnetic-paramagnetic
transition for the film is suppressed from the bulk system value, Tc, to the
interface localization-delocalization temperature Tci. The simulations show
that in general Tcd < Tci for the model film. The profile of the time-dependent
layer magnetization across the film shows that the dynamically ordered and
dynamically disordered phases coexist within the film for T < Tcd. In the
presence of competing surface fields, the dynamically ordered phase is
localized at one surface of the film.

</DOC>
<DOC>
<DOCNO> 71006 </DOCNO>
$\Delta$(1232) electroproduction amplitudes in chiral soliton models of


  The multipole amplitudes for the N - Delta electromagnetic transition are
computed in the framework of the linear sigma model and the chiral
chromodielectric model for small and moderate photon virtualities. The models
include quark and meson degrees of freedom and the nucleon and the delta are
clusters of three valence hedgehog quarks surrounded by meson clouds described
by coherent states. Angular momentum and isospin projections are performed to
endow model states representing the nucleon and the delta with proper quantum
numbers. Recoil corrections involved in the process $\gamma_{\rm v} N \to
\Delta$ are taken into account by performing linear momentum projection of the
initial and final baryon states. The ratios $E2/M1$ and $C2/M1$ are in good
agreement with the data in the two models, but the magnetic amplitude is better
reproduced in the Linear Sigma Model. The ratios show little dependence with
the model parameters. Both in the Linear Sigma Model and in the
Chromodielectric Model the charged pions are responsible for the non-vanishing
quadrupole-electric and -coulomb amplitudes. The recoil corrections enhance the
results obtained for the amplitudes without linear momentum projection,
improving the comparison with experimental data. The dependence of the
theoretical amplitudes with the choice of the reference frame is also studied.

</DOC>
<DOC>
<DOCNO> 118129 </DOCNO>
A Search for Exozodiacal Dust and Faint Companions Near Sirius, Procyon,


  We observed Sirius, Altair, and Procyon with the NICMOS Coronagraph on the
Hubble Space Telescope to look for scattered light from exozodiacal dust and
faint companions within 10 AU from these stars. We did not achieve enough
dynamic range to surpass the upper limits set by IRAS on the amount of
exo-zodiacal dust in these systems, but we did set strong upper limits on the
presence of nearby late-type and sub-stellar companions.

</DOC>
<DOC>
<DOCNO> 85222 </DOCNO>
Global properties of gravitational lens maps in a Lorentzian manifold


  In a general-relativistic spacetime (Lorentzian manifold), gravitational
lensing can be characterized by a lens map, in analogy to the lens map of the
quasi-Newtonian approximation formalism. The lens map is defined on the
celestial sphere of the observer (or on part of it) and it takes values in a
two-dimensional manifold representing a two-parameter family of worldlines. In
this article we use methods from differential topology to characterize global
properties of the lens map. Among other things, we use the mapping degree (also
known as Brouwer degree) of the lens map as a tool for characterizing the
number of images in gravitational lensing situations. Finally, we illustrate
the general results with gravitational lensing (a) by a static string, (b) by a
spherically symmetric body, (c) in asymptotically simple and empty spacetimes,
and (d) in weakly perturbed Robertson-Walker spacetimes.

</DOC>
<DOC>
<DOCNO> 122243 </DOCNO>
The luminosity calibration of the uvby-$\beta$ photometry


  The ESA HIPPARCOS satellite has provided astrometry of unprecedented
accuracy, allowing to reassess, improve and refine the pre-HIPPARCOS luminosity
calibrations. We review the "classical" absolute magnitude calibrations with
the Stroemgren-Crawford intermediate-band photometric system. A small zero
point correction of about 2-4% seems necessary, as well as to refine the
dependences on metallicity and projected rotational velocity. The need of a
rigorous statistical treatment of the extremely precise HIPPARCOS to derive
definite dependences of the luminosity on physical stellar parameters is
emphasized.

</DOC>
<DOC>
<DOCNO> 102017 </DOCNO>
The Dimension of the Planar Brownian Frontier is 4/3


  In a series of recent preprints, we have proven that with probability one the
Hausdorff dimension on the outer boundary of planar Brownian motion is 4/3,
confirming a conjecture by Mandelbrot. It is also shown that the Hausdorff
dimension of the set of cut points is a.s. 3/4. The present paper is an
expository outline of the arguments involved in the proof of these and related
results.

</DOC>
<DOC>
<DOCNO> 150654 </DOCNO>
A generalized p-form model in D=3


  A topological model in three dimensions is proposed. It combines the
Chern-Simons action with a BFK-model which was investigated recently by the
authors of hep-th/9906146. The finiteness of the model to all orders of
perturbation theory is shown in the framework of algebraic renormalization
procedure.

</DOC>
<DOC>
<DOCNO> 10144 </DOCNO>
Short-range spin correlations and induced local spin-singlet amplitude


  In this paper, from the microscopic Hubbard Hamiltonian we extract the local
spin-singlet amplitude due to short-range spin correlations, and quantify its
strength near half-filling. As a first application of the present approach, we
study a problem of the energy dispersion and its d-wave modulation in the
insulating cuprates, Sr$_{2}$CuO$_{2}$Cl$_{2}$ and Ca$_{2}$CuO$_{2}$Cl$_{2}$.
Without any adjustable parameters, most puzzling issues are naturally and
quantitatively explained within the present approach.

</DOC>
<DOC>
<DOCNO> 119907 </DOCNO>
Survey of rotation curves for northern spiral edge-on galaxies


  Rotational curves are measured for almost complete sample of 308 northern
spiral galaxies using the 6-m telescope. For observations we selected edge-on
galaxies from RFGC catalog with apparent axial ratio a/b>8, angular diameter
a<2', and declinations delta>+38deg above the Arecibo belt. About 97% of the
galaxies are detected in the H-alpha line. For them a typical rotation curve
extends till 87% of the standard galaxy radius. The rotation curve amplitude
shows close correlation with a width of the HI line. The median radial velocity
for the galaxies is 7800 km/sec, and the median maximum of the rotation curves
is 137 km/s. These new observational data will be used to study cosmic
streamings of galaxies seen on a scale of 200 Mpc.

</DOC>
<DOC>
<DOCNO> 13858 </DOCNO>
A dynamical approach to the microcanonical ensemble


  A statistical ensemble of paths on the phase-space energy surface and an
average over this set are defined. Effective motion equations from which
thermodynamic properties are extracted, are obtained by introducing a general
variational principle applied to the action averaged over these paths. The
method is applied first to the one dimensional (\beta)-FPU chain and then to
the two dimensional lattice (\phi ^{4}) model. In both cases the method gives a
good insight of some of their statistical and dynamical properties.

</DOC>
<DOC>
<DOCNO> 13665 </DOCNO>
Spike-Train Responses of a Pair of Hodgkin-Huxley Neurons with


  Model calculations have been performed on the spike-train response of a pair
of Hodgkin-Huxley (HH) neurons coupled by recurrent excitatory-excitatory
couplings with time delay. The coupled, excitable HH neurons are assumed to
receive the two kinds of spike-train inputs: the transient input consisting of
$M$ impulses for the finite duration ($M$: integer) and the sequential input
with the constant interspike interval (ISI). The distribution of the output ISI
$T_{\rm o}$ shows a rich of variety depending on the coupling strength and the
time delay. The comparison is made between the dependence of the output ISI for
the transient inputs and that for the sequential inputs.

</DOC>
<DOC>
<DOCNO> 100708 </DOCNO>
Erratum to the paper "A note on the factorization theorem of toric


  This is an erratum to math.AG/9803126, Tohoku 51 (1999) 489-537. This erratum
describes:
  1. the failure of the algorithm in [AMR] and [Morelli1] for the strong
factorization pointed out by Kalle Karu,
  2. the statement of a refined weak factorization theorem for toroidal
birational morphisms in [AMR], in the form utilized in [AKMR] for the proof of
the weak factorization theorem for general birationla maps, avoiding the use of
the above mentioned algorithm for the strong factorization, and 3. a list of
corrections for a few other mistakes in [AMR], mostly pointed out by Laurent
Bonavero.

</DOC>
<DOC>
<DOCNO> 151693 </DOCNO>
Observables of Non-Commutative Gauge Theories


  We construct gauge invariant operators in non-commutative gauge theories
which in the IR reduce to the usual operators of ordinary field theories (e.g.
F^2). We show that in the deep UV the two-point functions of these operators
admit a universal exponential behavior which fits neatly with the dual
supergravity results. We also consider the ratio between n-point functions and
two-point functions to find exponential suppression in the UV which we compare
to the high energy fixed angle scattering of string theory.

</DOC>
<DOC>
<DOCNO> 102404 </DOCNO>
K(n)-local duality for finite groups and groupoids


  We define an inner product (suitably interpreted) on the K(n)-local spectrum
LG := L_{K(n)}BG_+, where G is a finite group or groupoid. This gives an inner
product on E^*BG_+ for suitable K(n)-local ring spectra E. We relate this to
the usual inner product on the representation ring when n=1, and to the
Hopkins-Kuhn-Ravenel generalised character theory. We show that LG is a
Frobenius algebra object in the K(n)-local stable category, and we recall the
connection between Frobenius algebras and topological quantum field theories to
help analyse this structure. In many places we find it convenient to use
groupoids rather than groups, and to assist with this we include a detailed
treatment of the homotopy theory of groupoids. We also explain some striking
formal similarities between our duality and Atiyah-Poincare duality for
manifolds.

</DOC>
<DOC>
<DOCNO> 99918 </DOCNO>
Asymptotic behaviour of a solution for Kadomtsev-Petviashvili-2 equation


  An asymptotic behaviour of solution of Kadomtsev-Petviashvili-2 equation is
obtained as $t\to\infty$ uniformly with respect to spatial variables.

</DOC>
<DOC>
<DOCNO> 39615 </DOCNO>
Quark Mixing Matrix Studies and Lepton Flavor Violation Searches Using


  I review recent results from experiments on rare decays of kaons,
concentrating on searches for lepton flavor violation (LFV) and on measurements
of quark mixing (CKM) matrix elements. The LFV results are the culmination of
15 years of experimentation at Brookhaven National Laboratory and are unlikely
to be improved upon soon. The CKM studies derive from measurements of decay
rates of charged and neutral kaons into lepton anti-lepton pairs, both with and
without a charged or neutral pion. I discuss recent results and prospects for
improved measurements that could provide an unambiguous test of the Standard
Model explanation for CP violation. This paper is the written version of a talk
presented at the Lepton-Photon Conference in August 1999.

</DOC>
<DOC>
<DOCNO> 12694 </DOCNO>
Comparative statistical analysis of bacteria genomes in "word" context


  Statistical analysis of bacteria genomes texts has been performed on the
basis of 20 complete genomes origin from Genebank. It has been revealed that
the word ranked distributions are quite well approximated by logarithmic law.
Results obtained in the absent words investigation show the considerably
nonrandom character of DNA texts. In character of autocorrelation function
behavior in several genomes period 3 oscillations were found. Short range
autocorrelations are present in short ($n=3$) words and practically absent in
longer words.

</DOC>
<DOC>
<DOCNO> 122316 </DOCNO>
Non-Uniform Free-Free Absorption in the GPS Radio Galaxy 0108+388


  We have observed the canonical gigahertz-peaked spectrum source 0108+388 with
the VLBA at a range of frequencies above and below the spectral peak. The
activity that dominates the radio emission from 0108+388, which is also
classified as a Compact Symmetric Object, is thought to be less than 1000 years
old. We present strong evidence that the spectral turnover in 0108+388 results
from free-free absorption by non-uniform gas, possibly in the form of a disk in
the central tens of parsecs.

</DOC>
<DOC>
<DOCNO> 10148 </DOCNO>
Li$_2$VO(Si,Ge)O$_4$, a prototype of a two-dimensional frustrated


  NMR and magnetization measurements in Li$_2$VOSiO$_4$ and Li$_2$VOGeO$_4$ are
reported. The analysis of the susceptibility shows that both compounds are
two-dimensional $S=1/2$ Heisenberg antiferromagnets on a square lattice with a
sizeable frustration induced by the competition between the superexchange
couplings $J_1$ along the sides of the square and $J_2$ along the diagonal.
Li$_2$VOSiO$_4$ undergoes a low-temperature phase transition to a collinear
order, as theoretically predicted for $J_2/J_1 > 0.5$. Just above the magnetic
transition the degeneracy between the two collinear ground states is lifted by
the onset of a structural distortion.

</DOC>
<DOC>
<DOCNO> 120933 </DOCNO>
Development of Gold Contacted Flip-chip Detectors with IMARAD CZT


  We present initial results from our evaluation of a gold-contacted pixellated
detector using cadmium zinc telluride substrate produced by IMARAD Imaging
Systems. The Horizontal Bridgman (HB) grown crystals from IMARAD have been
shown to produce high resolution photopeaks, but they are also seen to have
large leakage current. Our previous tests with IMARAD CZT showed that the use
of indium anodes and gold cathode improved the resistivity compared to the
standard indium-contacted detectors. We seek to test whether simple evaporated
gold contacts alone could also reduce the leakage current and thus improve the
spectral resolution, especially in the 10-100 keV energy range. We have
fabricated several metal-semiconductor-metal (MSM) detectors with a 4x4 array
of pixels on 10x10 mm substrates. Measurements of the detectors' leakage
current, spectral response, and temperature sensitivity are presented and
compared to IMARAD's ohmic contact detector and gold contact MSM detectors made
of High Pressure Bridgman (HPB) material. Finally, we show preliminary results
from a tiled flip-chip pixellated detector made using the IMARAD detectors.

</DOC>
<DOC>
<DOCNO> 9151 </DOCNO>
Dynamical models for sand ripples beneath surface waves


  We introduce order parameter models for describing the dynamics of sand
ripple patterns under oscillatory flow. A crucial ingredient of these models is
the mass transport between adjacent ripples, which we obtain from detailed
numerical simulations for a range of ripple sizes. Using this mass transport
function, our models predict the existence of a stable band of wavenumbers
limited by secondary instabilities. Small ripples coarsen in our models and
this process leads to a sharply selected final wavenumber, in agreement with
experimental observations.

</DOC>
<DOC>
<DOCNO> 13995 </DOCNO>
Comment on "Melting of Isolated Tin Nanoparticles"


  Comment on the paper of T.Bachels, H. J. G\"{u}ntherodt and R.Sch\"{a}fer :
"Melting of Isolated Tin Nanoparticles".

</DOC>
<DOC>
<DOCNO> 9375 </DOCNO>
How fast does Langton's ant move?


  The automaton known as `Langton's ant' exhibits a dynamical transition from a
disordered phase to an ordered phase where the particle dynamics (the ant)
produces a regular periodic pattern (called `highway'). Despite the simplicity
of its basic algorithm, Langton's ant has remained a puzzle in terms of
analytical description. Here I show that the highway dynamics obeys a discrete
equation where from the speed of the ant ($c={\sqrt 2}/52$) follows exactly.

</DOC>
<DOC>
<DOCNO> 11276 </DOCNO>
Experimental evidence for the formation of stripe phases in Si/SiGe


  We observe pronounced transport anisotropies in magneto-transport experiments
performed in the two-dimensional electron system of a Si/SiGe heterostructure.
They occur when an in-plane field is used to tune two Landau levels with
opposite spin to energetic coincidence. The observed anisotropies disappear
drastically for temperatures above 1 K. We propose that our experimental
findings may be caused by the formation of a unidirectional stripe phase
oriented perpendicular to the in-plane field.

</DOC>
<DOC>
<DOCNO> 80752 </DOCNO>
Scaling and Further Tests of Heavy Meson Decay Constant Determinations


  We present results for the B_s meson decay constant f_{B_s} from simulations
at three lattice spacings in the range a^{-1}=1.1 to 2.6 GeV using NRQCD heavy
quarks and clover light quarks in the quenched approximation. We study scaling
of this quantity and check the consistency between mesons decaying from rest
and from a state with nonzero spatial momentum. The cancellation of power law
contributions that arise in the NRQCD formulation of heavy-light currents is
discussed. On the coarsest lattice the D_s meson decay constant f_{D_s} is
calculated. Our best values for the decay constants are given by f_{B_s} =
187(4)(4)(11)(2)(7)(6) MeV and f_{D_s} = 223(6)(31)(38)(23)(9)(^{+3}_{-1}) MeV.

</DOC>
<DOC>
<DOCNO> 11116 </DOCNO>
Short-time critical dynamics


  An introductory review to short-time critical dynamics is given. From the
scaling relation valid already in the early stage of the evolution of a system
at or near the critical point, one derives power law behaviour for various
quantities. By a numerical simulation of the system one can measure the
critical exponents and, by searching for the best power law behaviour, one can
determine the critical point. Critical slowing down as well as finite size
corrections are nearly absent, since the correlation length is still small for
times far before equilibrium is reached. By measuring the (pseudo) critical
points it is also possible to distinguish (weak) first-order from second-order
phase transitions.

</DOC>
<DOC>
<DOCNO> 68818 </DOCNO>
The Cosmological Constant


  This is a review of the physics and cosmology of the cosmological constant.
Focusing on recent developments, I present a pedagogical overview of cosmology
in the presence of a cosmological constant, observational constraints on its
magnitude, and the physics of a small (and potentially nonzero) vacuum energy.

</DOC>
<DOC>
<DOCNO> 170040 </DOCNO>
Three qubits can be entangled in two inequivalent ways


  Invertible local transformations of a multipartite system are used to define
equivalence classes in the set of entangled states. This classification
concerns the entanglement properties of a single copy of the state.
Accordingly, we say that two states have the same kind of entanglement if both
of them can be obtained from the other by means of local operations and
classical communcication (LOCC) with nonzero probability. When applied to pure
states of a three-qubit system, this approach reveals the existence of two
inequivalent kinds of genuine tripartite entanglement, for which the GHZ state
and a W state appear as remarkable representatives. In particular, we show that
the W state retains maximally bipartite entanglement when any one of the three
qubits is traced out. We generalize our results both to the case of higher
dimensional subsystems and also to more than three subsystems, for all of which
we show that, typically, two randomly chosen pure states cannot be converted
into each other by means of LOCC, not even with a small probability of success.

</DOC>
<DOC>
<DOCNO> 70136 </DOCNO>
Sparticle spectrum and dark matter in type I string theory with an


  The supersymmetric particle spectrum is calculated in type I string theories
formulated as orientifold compactifications of type IIB string theory. A string
scale at an intermediate value of $10^{11}-10^{12}$ GeV is assumed and extra
vector-like matter states are introduced to allow unification of gauge coupling
constants to occur at this scale. The qualitative features of the spectrum are
compared with Calabi-Yau compactification of the weakly coupled heterotic
string and with the eleven dimensional supergravity limit of $M$-theory. Some
striking differences are observed. Assuming that the lightest neutralino
provides the dark matter in the universe, further constraints on the sparticle
spectrum are obtained. Direct detection rates for dark matter are estimated.

</DOC>
<DOC>
<DOCNO> 39909 </DOCNO>
A High-Precision Measurement of the Left-Right Z Boson Cross-Section


  We present a measurement of the left-right cross-section asymmetry (ALR) for
Z boson production by e+e- collisions. The measurement includes the final data
taken with the SLD detector at the SLAC Linear Collider (SLC) during the period
1996-1998. Using a sample of 383,487 Z decays collected during the 1996-1998
runs we measure the pole-value of the asymmetry, ALR0, to be 0.15056+-0.00239
which is equivalent to an effective weak mixing angle of sin2th(eff) =
0.23107+-0.00030. Our result for the complete 1992-1998 dataset comprising 537
thousand Z decays is sin2th(eff) = 0.23097+-0.00027.

</DOC>
<DOC>
<DOCNO> 11325 </DOCNO>
X-ray induced persistent photoconductivity in Si-doped


  We demonstrate that X-ray irradiation can be used to induce an
insulator-metal transition in Si-doped Al$_{0.35}$Ga$_{0.65}$As, a
semiconductor with {\it DX} centers. The excitation mechanism of the {\it DX}
centers into their shallow donor state was revealed by studying the
photoconductance along with fluorescence. The photoconductance as a function of
incident X-ray energy exhibits an edge both at the Ga and As K-edge, implying
that core-hole excitation of Ga and As are efficient primary steps for the
excitation of {\it DX} centers. A high quantum yield ($\gg 1$) suggests that
the excitation is indirect and nonlocal, due to secondary electrons, holes, and
fluorescence photons.

</DOC>
<DOC>
<DOCNO> 85510 </DOCNO>
Hamiltonian structure and quantization of 2+1 dimensional gravity


  It is shown that the reduced particle dynamics of 2+1 dimensional gravity in
the maximally slicing gauge has hamiltonian form. This is proved directly for
the two body problem and for the three body problem by using the Garnier
equations for isomonodromic transformations. For a number of particles greater
than three the existence of the hamiltonian is shown to be a consequence of a
conjecture by Polyakov which connects the auxiliary parameters of the fuchsian
differential equation which solves the SU(1,1) Riemann-Hilbert problem, to the
Liouville action of the conformal factor which describes the space-metric. We
give the exact diffeomorphism which transforms the expression of the spinning
cone geometry in the Deser, Jackiw, 't Hooft gauge to the maximally slicing
gauge. It is explicitly shown that the boundary term in the action, written in
hamiltonian form gives the hamiltonian for the reduced particle dynamics. The
quantum mechanical translation of the two particle hamiltonian gives rise to
the logarithm of the Laplace-Beltrami operator on a cone whose angular deficit
is given by the total energy of the system irrespective of the masses of the
particles thus proving at the quantum level a conjecture by 't Hooft on the two
particle dynamics. The quantum mechanical Green's function for the two body
problem is given.

</DOC>
<DOC>
<DOCNO> 123234 </DOCNO>
IY UMa: accretion disc evolution after superoutburst


  CCD photometry of the newly discovered eclipsing dwarf nova IY UMa is used to
study the physical properties of the accretion disc in the late decline and
quiescence stages. Eclipse mapping analysis shows that in these stages the
accretion disc is cool with approximately flat radial brightness temperature
distribution and T_BR about 5000-5500 K. The hot spot is found to lie close
along the stream trajectory at distance 0.36a and 0.25a from the disc center in
February and March. The orbital hump strength decreases by about 30 % in a
month. Taking the smallest possible size of the hot spot, we derive an upper
limit for its brightness temperature, 15900 K and 13800 K, respectively.

</DOC>
<DOC>
<DOCNO> 10378 </DOCNO>
An electron paramagnetic resonance study of Pr_{0.6}Ca_{0.4}MnO_{3}


  We report the first electron paramagnetic resonance studies of single
crystals and powders of Pr_{0.6}Ca_{0.4}MnO_{3} in the 300-4.2 K range,
covering the charge ordering transition at ~ 240 K and antiferromagnetic
transition (T_N) at ~ 170 K. The asymmetry parameter for the Dysonian single
crystal spectra shows anomalous increase at T_{co}. Below T_{co} the g-value
increases continuously, suggesting a gradual strengthening of orbital ordering.
The linewidth undergoes a sudden increase at T_{co} and continues to increase
down to T_N. The intensity increases as the temperature is decreased till
T_{co} due to the renormalization of magnetic susceptibility arising from the
build up of ferromagnetic correlations. The value of the exchange constant, J,
is estimated to be 154 K.

</DOC>
<DOC>
<DOCNO> 118805 </DOCNO>
Possibly interacting Vorontsov-Velyaminov galaxies. I. Observations of


  Among the galaxies which were included in the Atlas and Catalogue of
Interacting galaxies by Vorontsov-Velyaminov (hereafter VV) as multiple systems
("nests", "chains" and similarly looking systems), there are many objects,
where the interaction is not evident. Some of them are single objects,
including low-mass galaxies with active star formation (SF). In this work we
present the description of observations and results of the long-slit
spectrophotometry with the Russian 6-m telescope of three VV-galaxies looking
like double or multiple systems, and HI-observations of one of them in order to
elucidate their nature, determine their metallicity, kinematic properties and
the evolution status. Galaxies VV432 and VV747 are found to be dwarf systems
with low oxygen abundance (O/H = 1/22 and 1/12 of the solar value,
respectively). Their velocity curves indicate quite slow rotation with
respective maximum velocities of about 60 and 80 km/s, in agreement with their
low luminosities. The distance to VV432 is rather uncertain. If it is a member
of Virgo Cluster, this is the most metal-deficient known galaxy of this
aggregate. For galaxy VV543 the measured emission-line redshift 0.047 appeared
ten times larger than it was given in the original paper and is cited in
databases. This "system" evidently represents an optical pair of two galaxies
with large velocity difference. The fainter western component is an HII-galaxy,
while the brighter one is an absorption-line early-type galaxy with the radial
velocity being 1600 km/s lower.

</DOC>
<DOC>
<DOCNO> 119035 </DOCNO>
Comparing Tycho-2 Astrometry with UCAC1


  The Tycho-2 Catalogue, released in February 2000, is based on the ESA
Hipparcos space mission data and various ground-based catalogs for proper
motions. An external comparison of the Tycho-2 astrometry is presented here
using the first U.S. Naval Observatory CCD Astrograph Catalog (UCAC1). The
UCAC1 data were obtained from observations performed at CTIO between February
1998 and November 1999, using the 206 mm aperture 5-element lens astrograph and
a 4k x 4k CCD. Only small systematic differences in position between Tycho-2
and UCAC1 up to 15 milliarcseconds (mas) are found, mainly as a function of
magnitude. The standard deviations of the distributions of the position
differences are in the 35 to 140 mas range, depending on magnitude. The
observed scatter in the position differences is about 30% larger than expected
from the combined formal, internal errors, also depending on magnitude. The
Tycho-2 Catalogue has the more precise positions for bright stars (V <= 10 mag)
while the UCAC1 positions are significantly better at the faint end (11 mag <=
V <= 12.5 mag) of the magnitude range in common. UCAC1 goes much fainter (to
R=16) than Tycho-2; however complete sky coverage is not expected before mid
2003.

</DOC>
<DOC>
<DOCNO> 71204 </DOCNO>
Masses of Flavor Singlet Hybrid Baryons


  We study the possibility that four iso-singlet baryons $\Lambda_s(1405)$
$J^P=1/2^{-}$, $\Lambda_s(1520)$ $J^P=3/2^{-}$, $\Lambda_c(2593)$ $J^P=1/2^{-}$
and $\Lambda_c(2625)$ $J^P=3/2^{-}$ are hybrids: three quark one gluon states
(udsg). We calculate the mass separations of the candidates, using a
degeneracy-lifting hyperfine interaction from an effective single colored gluon
exchange between the constituents. The correct ordering of masses is obtained
(contrary to the case for the conventional interpretation as 3 quarks with L=1)
and the splittings are plausible. The parity of these states is not measured,
only assumed to be negative. In the hybrid picture, the lightest states are
parity even and the parity odd counterparts lie about 300 MeV higher. Thus the
hybrid ansatz predicts that either the parity of the $\Lambda(1405)$ etc is
positive, or that there are undiscovered positive parity states about 300 MeV
lower. We also remark that in this picture, the H-dibaryon mass may be around
1.5 GeV.

</DOC>
<DOC>
<DOCNO> 102169 </DOCNO>
The structure of Chip Firing Games and related models


  In this paper, we study the dynamics of sand grains falling in sand piles.
Usually sand piles are characterized by a decreasing integer partition and
grain moves are described in terms of transitions between such partitions. We
study here four main transition rules. The more classical one, introduced by
Brylawski (1973) induces a lattice structure $L_B (n)$ (called dominance
ordering) between decreasing partitions of a given integer n. We prove that a
more restrictive transition rule, called SPM rule, induces a natural partition
of L_B (n) in suborders, each one associated to a fixed point for SPM rule. In
the second part, we extend the SPM rule in a natural way and obtain a model
called Chip Firing Game (Goles and Kiwi, 1993). We prove that this new model
has interesting properties: the induced order is a lattice, a natural greedoid
can be associated to the model and it also defines a strongly convergent game.
In the last section, we generalize the SPM rule in another way and obtain other
lattice structure parametrized by some t: L(n,t), which form for -n+2 <= t <= n
a decreasing sequence of lattices. For each t, we characterize the fixed point
of L(n,t) and give the value of its maximal sized chain's lenght. We also note
that L(n,-n+2) is the lattice of all compositions of n.

</DOC>
<DOC>
<DOCNO> 8493 </DOCNO>
Spin and charge inhomogeneities in high-T_c cuprates: Evidence from NMR


  In this communication we consider the doping dependence of the strong
antiferromagnetic spin fluctuations in the cuprate superconductors. We
investigate the effect of an incommensurate magnetic response, as recently
observed in inelastic neutron scattering (INS) experiments on several
YBa_2Cu_3O_{6+x} compounds, on the spin-lattice and spin-echo relaxation rates
measured in nuclear magnetic resonance (NMR) experiments. We conclude that a
consistent theoretical description of INS and NMR can be reached if one assumes
spatially inhomogeneous but locally commensurate spin correlations and that NMR
and INS experiments can be described within a single theoretical scenario. We
discuss a simple scenario of spin and charge inhomogeneities which includes the
main physical ingredients required for consistency with experiments.

</DOC>
<DOC>
<DOCNO> 69002 </DOCNO>
Quantum mechanics of baryogenesis


  The cosmological baryon asymmetry can be explained as remnant of heavy
Majorana neutrino decays in the early universe. We study this
out-of-equilibrium process by means of Kadanoff-Baym equations which are solved
in a perturbative expansion. To leading order the problem is reduced to solving
a set of Boltzmann equations for distribution functions.

</DOC>
<DOC>
<DOCNO> 102452 </DOCNO>
Stringy Geometry and Topology of Orbifolds


  This is a survey article on the recent development of
 "stringy geometry and topology of orbifolds", a new subject of mathematics
motivated by orbifold string theory.

</DOC>
<DOC>
<DOCNO> 69774 </DOCNO>
Coherent Exclusive Exponentiation For Precision Monte Carlo Calculations


  We present the new Coherent Exclusive Exponentiation (CEEX), the older
Exclusive Exponentiation (EEX) and the semi-analytical Inclusive Exponentiation
(IEX) for the process $e^+e^-\to f\bar{f} +n\gamma$, $f=\mu,\tau,d,u,s,c,b$
with validity for centre of mass energies from $\tau$ lepton threshold to 1TeV,
that is for LEP1, LEP2, SLC, future Linear Colliders, $b,c,\tau$-factories etc.
They are based on Yennie-Frautschi-Suura exponentiation. In CEEX effects due to
photon emission from initial beams and outgoing fermions are calculated in QED
up to second-order, including all interference effects. Electroweak corrections
are included in first-order, at the amplitude level. Beams can be polarized
longitudinally and transversely, and all spin correlations are incorporated in
an exact manner. EEX is more primitive, lacks initial-final interferences, but
it is valuable for testing the newer CEEX. IEX provides us set of a
sophisticated semi-analytical formulas for the total cross section and selected
inclusive distributions which are mainly used for cross-checks of the MC
results. We analyse numerical results at the Z-peak 189 GeV and 500 GeV for
simple kinematical cuts (comparisons with IEX) and for realistic experimental
cuts. Physical precision and technical precision are determined for the total
cross section and for the charge asymmetry.

</DOC>
<DOC>
<DOCNO> 84853 </DOCNO>
Oscillatory Behaviour in Homogeneous String Cosmology Models


  Some spatially homogeneous Bianchi type I cosmological models filled with
homogeneous ``electric'' $p$-form fields are shown to mimic the never-ending
oscillatory behaviour of generic string cosmologies established recently. The
validity of the ``Kasner-free-flights plus collisions-on-potential-walls''
picture is also illustrated in the case of known, non-chaotic, superstring
solutions.

</DOC>
<DOC>
<DOCNO> 8494 </DOCNO>
Coexistent State of Charge Density Wave and Spin Density Wave in


  We theoretically study how the coexistent state of the charge density wave
and the spin density wave in the one-dimensional quarter filled band is
enhanced by magnetic fields. We found that when the correlation between
electrons is strong the spin density wave state is suppressed under high
magnetic fields, whereas the charge density wave state still remains. This will
be observed in experiments such as the X-ray measurement.

</DOC>
<DOC>
<DOCNO> 69394 </DOCNO>
Influence of the U(1)_A Anomaly on the QCD Phase Transition


  The SU(3)_{r} \times SU(3)_{\ell} linear sigma model is used to study the
chiral symmetry restoring phase transition of QCD at nonzero temperature. The
line of second order phase transitions separating the first order and smooth
crossover regions is located in the plane of the strange and nonstrange quark
masses. It is found that if the U(1)_{A} symmetry is explicitly broken by the
U(1)_{A} anomaly then there is a smooth crossover to the chirally symmetric
phase for physical values of the quark masses. If the U(1)_{A} anomaly is
absent, then there is a phase transition provided that the \sigma meson mass is
at least 600 MeV. In both cases, the region of first order phase transitions in
the quark mass plane is enlarged as the mass of the \sigma meson is increased.

</DOC>
<DOC>
<DOCNO> 13817 </DOCNO>
Layer-resolved magneto-optical Kerr effect in semi-infinite


  The contour integration technique applied to calculate the optical
conductivity tensor at finite temperatures in the case of inhomogeneous surface
layered systems within the framework of the spin-polarized relativistic
screened Korringa-Kohn-Rostoker band structure method is extended to arbitrary
polarizations of the electric field. It is shown that besides the inter-band
contribution, the contour integration technique also accounts for the
intra-band contribution too. Introducing a layer-resolved complex Kerr angle,
the importance of the first, non-magnetic buffer layer below the ferromagnetic
surface on the magneto-optical Kerr effect in the $\mathrm{Co} \mid
\mathrm{Pt}_m$ multilayer system is shown. Increasing the thickness of the
buffer Pt, the layer-resolved complex Kerr angles follow a linear dependence
with respect to m only after nine Pt mono-layers.

</DOC>
<DOC>
<DOCNO> 68296 </DOCNO>
The Higgs Working Group: Summary Report


  Report of the Higgs working group for the Workshop "Physics at TeV
Colliders", Les Houches, France 8-18 June 1999. It contains 6 separate
sections:
   1. Measuring Higgs boson couplings at the LHC.
   2. Higgs boson production at hadron colliders at NLO.
   3. Signatures of Heavy Charged Higgs Bosons at the LHC.
   4. Light stop effects and Higgs boson searches at the LHC.
   5. Double Higgs production at TeV Colliders in the MSSM.
   6. Programs and Tools for Higgs Bosons.

</DOC>
<DOC>
<DOCNO> 178418 </DOCNO>
Meson Particle-Hole Dynamics


  Particle-hole modes with quantum numbers of pions and negative kaons can
propagate in nuclear matter. We discuss possible manifestations of these modes
in experiments on heavy-ion collisions and on neutrino-nucleus scattering.
Calculations of reaction rates in medium can be harmed by double counting,
which arises because the very same quantum numbers can be carried in medium as
by single particle excitations as by multi-particle ones. We argue that the
optical theorem written in terms of the non-equilibrium Green's functions
provides a convenient formalism (closed diagram technique) void of double
counting.

</DOC>
<DOC>
<DOCNO> 10998 </DOCNO>
Bubble propagation in a helicoidal molecular chain


  We study the propagation of very large amplitude localized excitations in a
model of DNA that takes explicitly into account the helicoidal structure. These
excitations represent the ``transcription bubble'', where the hydrogen bonds
between complementary bases are disrupted, allowing access to the genetic code.
We propose these kind of excitations in alternative to kinks and breathers. The
model has been introduced by Barbi et al. [Phys. Lett. A 253, 358 (1999)], and
up to now it has been used to study on the one hand low amplitude breather
solutions, and on the other hand the DNA melting transition. We extend the
model to include the case of heterogeneous chains, in order to get closer to a
description of real DNA; in fact, the Morse potential representing the
interaction between complementary bases has two possible depths, one for A-T
and one for G-C base pairs. We first compute the equilibrium configurations of
a chain with a degree of uncoiling, and we find that a static bubble is among
them; then we show, by molecular dynamics simulations, that these bubbles, once
generated, can move along the chain. We find that also in the most unfavourable
case, that of a heterogeneous DNA in the presence of thermal noise, the
excitation can travel for well more 1000 base pairs.

</DOC>
<DOC>
<DOCNO> 151676 </DOCNO>
On plausible violations of the Riemann conjecture due to fractal


  This paper has been withdrawn

</DOC>
<DOC>
<DOCNO> 80580 </DOCNO>
Pions in Lattice QCD with the Overlap Fermions at Strong Gauge Coupling


  In the previous paper we developed a strong-coupling expansion for the
lattice QCD with the overlap fermions and showed that L\"usher's "extended"
chiral symmetry is spontaneously broken in some parameter region of the overlap
fermions. In this paper, we obtain a low-energy effective action and show that
there exist quasi-Nambu-Goldsone bosons which are identified as the pions. The
pion field is a {\em nonlocal} composite field of quark and anti-quark even at
the strong-coupling limit because of the nonlocality of the overlap fermion
formalism and L\"usher's chiral symmetry. The pions become massless in the
limit of the vanishing bare-quark mass as it is desired.

</DOC>
<DOC>
<DOCNO> 122073 </DOCNO>
Balmer-Dominated Spectra of Nonradiative Shocks in the Cygnus Loop, RCW


  We present an observational and theoretical study of the optical emission
from nonradiative shocks in three supernova remnants: the Cygnus Loop, RCW 86
and Tycho. The spectra of these shocks are dominated by collisionally excited
hydrogen Balmer lines which have both a broad component caused by
proton-neutral charge exchange and a narrow component caused by excitation of
cold neutrals entering the shock. In each remnant we have obtained the broad to
narrow flux ratios of the Halpha and Hbeta lines and measured the Halpha broad
component width.
  A new numerical shock code computes the broad and narrow Balmer line emission
from nonradiative shocks in partially neutral gas. The Balmer line fluxes are
sensitive to Lyman line trapping and the degree of electron-proton temperature
equilibration. The code calculates the density, temperature and size of the
postshock ionization layer and uses a Monte Carlo simulation to compute narrow
Balmer line enhancement from Lyman line trapping. The initial fraction of the
shock energy allocated to the electrons and protons (the equilibration) is a
free parameter. Our models show that variations in electron-proton temperature
equilibration and Lyman line trapping can reproduce the observed range of broad
to narrow ratios. The results give 80%-100% equilibration in nonradiative
portions of the NE Cygnus Loop (v_shock ~ 300 km/s), 40%-50% equilibration in
nonradiative portions of RCW 86 (v_shock ~ 600 km/s) and <~ 20% equilibration
in Tycho (v_shock ~ 2000 km/s). Our results suggst an inverse correlation
between magnetosonic Mach number and equilibration in the observed remnants.

</DOC>
<DOC>
<DOCNO> 102092 </DOCNO>
Oriented Lagrangian Matroids


  In this paper we present a definition of oriented Lagrangian symplectic
matroids and their representations. Classical concepts of orientation and this
extension may both be thought of as stratifications of thin Schubert cells into
unions of connected components. The definitions are made first in terms of a
combinatorial axiomatisation, and then again in terms of elementary geometric
properties of the Coxeter matroid polytope. We also generalise the concept of
rank and signature of a quadratic form to symplectic Lagrangian matroids in a
surprisingly natural way.

</DOC>
<DOC>
<DOCNO> 13825 </DOCNO>
Transport and Noise Characteristics of Submicron High-Temperature


  We have investigated the transport and noise properties of submicron YBCO
bicrystal grain-boundary junctions prepared using electron beam lithography.
The junctions show an increased conductance for low voltages reminiscent of
Josephson junctions having a barrier with high transmissivity. The voltage
noise spectra are dominated by a few Lorentzian components. At low temperatures
clear two-level random telegraph switching (RTS) signals are observable in the
voltage vs time traces. We have investigated the temperature and voltage
dependence of individual fluctuators both from statistical analysis of voltage
vs time traces and from fits to noise spectra. A transition from tunneling to
thermally activated behavior of individual fluctuators was clearly observed.
The experimental results support the model of charge carrier traps in the
barrier region.

</DOC>
<DOC>
<DOCNO> 174576 </DOCNO>
First Measurement of Antikaon Phase-Space Distributions in


  Differential production cross sections of K$^-$ and K$^+$ mesons have been
measured as function of the polar emission angle in Ni+Ni collisions at a beam
energy of 1.93 AGeV. In near-central collisions, the spectral shapes and the
widths of the rapidity distributions of K$^-$ and K$^+$ mesons are in agreement
with the assumption of isotropic emission. In non-central collisions, the K$^-$
and K$^+$ rapidity distributions are broader than expected for a single thermal
source. In this case, the polar angle distributions are strongly
forward-backward peaked and the nonisotropic contribution to the total yield is
about one third both for K$^+$ and K$^-$ mesons. The K$^-$/K$^+$ ratio is found
to be about 0.03 independent of the centrality of the reaction. This value is
significantly larger than predicted by microscopic transport calculations if
in-medium modifications of K mesons are neglected.

</DOC>
<DOC>
<DOCNO> 118387 </DOCNO>
Accretion Rates onto Massive Black Holes in Four Quiescent Elliptical


  Four quiescent elliptical galaxies were imaged with the NRAO VLA at 8.5 GHz.
Within the context of canonical advection-dominated accretion flows (ADAFs),
these VLA images plus published black hole masses constrain the accretion rates
to be $ <1.6\times10^{-4}$, $ <3.6\times10^{-4}$, $\le7.8\times10^{-4}$, and
$\le7.4\times10^{-4}$ of the Eddington rates. These ADAF accretion rates
derived at 8.5 GHz have important implications for the levels of soft and hard
X-rays expected from these quiescent galaxies.

</DOC>
<DOC>
<DOCNO> 117957 </DOCNO>
The role of outflows and star formation efficiency in the evolution of


  A phenomenological model for chemical enrichment in early-type galaxies is
presented, in which the process of star formation is reduced to a set of four
parameters: star formation efficiency (Ceff), fraction of ejected gas in
outflows (Bout), formation redshift (zF) and infall timescale (Tf). Out of
these four parameters, only variations of Bout or Ceff can account for the
color-magnitude relation. A range of outflows results in a metallicity
sequence, whereas a range of star formation efficiencies will yield a mixed age
+ metallicity sequence. The age-metallicity degeneracy complicates the issue of
determining which mechanism contributes the most (i.e. outflows versus
efficiency). However, the determination of the slope of the correlation between
mass-to-light ratio and mass in clusters at moderate or high redshift will
allow us to disentangle age and metallicity.

</DOC>
<DOC>
<DOCNO> 8847 </DOCNO>
Two Stages in the evolution of binary alkali Bose-Einstein condensate


  Two stages of quantum spinodal decomposition is proposed and analyzed for
this highly non-equilibrium process. Both time and spatial scales for the
process are found. Qualitative agreement with existing data is found. Some
cases the agreements are quantitative. Further experimental verifications are
indicated.

</DOC>
<DOC>
<DOCNO> 121857 </DOCNO>
Status and Current Sensitivity of the CELESTE Experiment


  The CELESTE experiment uses the heliostats of an old solar farm in the French
Pyrenees to detect gamma ray air showers by the atmospheric Cerenkov technique.
CELESTE has been operating since November 1999 with an array of 40 heliostats
fully instrumented with 1GHz flash ADCs.
 Significant advances have been made in the detector simulations and in the
data analysis techniques.
 We report here on results from recent observations of the Crab nebula above an
energy threshold of 50GeV.
 The results and simulations illustrate the current sensitivity of the
experiment.

</DOC>
<DOC>
<DOCNO> 120889 </DOCNO>
[Ne II] 12.8 Micron Images of Four Galactic Ultracompact H II Regions:


  We present the results of ground-based imaging spectroscopy of the [Ne II]
12.8 micron line emitted from the ultracompact (UC) H II regions; W51d,
G45.12+0.13, G35.20-1.74 and Monoceros R2, with 2arcsec spatial resolution. We
found that the overall distribution of the [Ne II] emission is generally in
good agreement with the radio (5 or 15 GHz) VLA distribution for each source.
The Ne+ abundance ([Ne+/H+]) distributions are also derived from the [Ne II]
and the radio maps. As for G45.12+0.13 and W51d, the Ne+ abundance decreases
steeply from the outer part of the map toward the radio peak. On the other
hand, the Ne+ abundance distributions of G35.20-1.74 and Mon R2 appear rather
uniform. These results can be interpreted by the variation of ionizing
structures of neon, which is primarily determined by the spectral type of the
ionizing stars. We have evaluated the effective temperature of the ionizing
star by comparing the Ne+ abundance averaged over the whole observed region
with that calculated by H II region models based on recent non-LTE stellar
atmosphere models: 39,100 (+1100, -500) K (O7.5V-O8V) for W51d, 37,200 (+1000,
-700) K (O8V-O8.5V) for G45.12+0.13, 35,000-37,600 (+1500, -600) K (O8V-O9V)
for G35.20-1.74, and < 34,000 K (< B0V) for Mon R2. These effective
temperatures are consistent with those inferred from the observed Ne+ abundance
distributions.

</DOC>
<DOC>
<DOCNO> 152017 </DOCNO>
Quantum Cauchy problem in cosmology


  We develop a general framework for effective equations of expectation values
in quantum cosmology and pose for them the quantum Cauchy problem with
no-boundary and tunneling wavefunctions. We apply this framework in the model
with a big negative non-minimal coupling, which incorporates a recently
proposed low energy (GUT scale) mechanism of the quantum origin of the
inflationary Universe and study the effects of the quantum inflaton mode.

</DOC>
<DOC>
<DOCNO> 9109 </DOCNO>
Quantum Phase Transitions in the Shastry-Sutherland Model for $\rm\bf


  We investigate the quantum phase transitions in the frustrated
antiferromagnetic Heisenberg model for $\rm SrCu_2(BO_3)_2$ by using the series
expansion method. It is found that a novel spin-gap phase, which is
adiabatically connected to the plaquette-singlet phase, exists between the
dimer and the magnetically ordered phases known so far. When the ratio of the
competing exchange couplings $\alpha(=J'/J)$ is varied, this spin-gap phase
exhibits the first- (second-) order quantum phase transition to the dimer (the
magnetically ordered) phase at the critical point $\alpha_{c1}=0.677(2)$
($\alpha_{c2}=0.86(1)$). Our results shed light on some controversial arguments
about the nature of the quantum phase transitions in this model.

</DOC>
<DOC>
<DOCNO> 12906 </DOCNO>
Classical Localization of an Unbound Particle in a Two-Dimensional


  In periodic, two-dimensional potentials a classical particle might be
expected to escape from any finite region if it has enough energy to escape
from a single cell. However, for a class of sinusoidal potentials in which the
barriers between neighboring cells can be varied, numerical tridiagonalization
of Liouville's equation for the evolution of functions on phase space reveals a
transition from localized to delocalized motion at a total energy significantly
above that needed to escape from a single cell. It is argued that this purely
elastic phenomenon increases the effective barrier for diffusion of atoms on
crystalline surfaces and changes its temperature dependence at low temperatures
when inelastic events are rare.

</DOC>
<DOC>
<DOCNO> 84376 </DOCNO>
Indications of causal set cosmology


  Within the context of a recently proposed family of stochastic dynamical laws
for causal sets, one can ask whether the universe might have emerged from the
quantum-gravity era with a large enough size and with sufficient homogeneity to
explain its present-day large-scale structure. In general, such a scenario
would be expected to require the introduction of very large or very small
fundamental parameters into the theory. However, there are indications that
such ``fine tuning'' is not necessary, and a large homogeneous and isotropic
cosmos can emerge naturally, thanks to the action of a kind of renormalization
group associated with cosmic cycles of expansion and re-contraction.

</DOC>
<DOC>
<DOCNO> 151122 </DOCNO>
E8 Gauge Theory, and a Derivation of K-Theory from M-Theory


  The partition function of Ramond-Ramond p-form fields in Type IIA
supergravity on a ten-manifold X contains subtle phase factors that are
associated with T-duality, self-duality, and the relation of the RR fields to
K-theory. The analogous partition function of M-theory on X x S1 contains
subtle phases that are similarly associated with E8 gauge theory. We analyze
the detailed phase factors on the two sides and show that they agree, thereby
testing M-theory/Type IIA duality as well as the K-theory formalism in an
interesting way. We also show that certain D-brane states wrapped on nontrivial
homology cycles are actually unstable, that (-1)^{F_L} symmetry in Type IIA
superstring theory depends in general on a cancellation between a fermion
anomaly and an anomaly of RR fields, and that Type IIA superstring theory with
no wrapped branes is well-defined only on a spacetime with W_7=0.

</DOC>
<DOC>
<DOCNO> 69552 </DOCNO>
NNLO evolution of deep-inelastic structure functions: the singlet case


  We study the next-to-next-to-leading order (NNLO) evolution of flavour
singlet parton densities and structure functions in massless perturbative QCD.
Present information on the corresponding three-loop splitting functions is used
to derive parametrizations of these quantities, including Bjorken-x dependent
estimates of their residual uncertainties. Compact expressions are also
provided for the exactly known, but in part rather lengthy two-loop singlet
coefficient functions. The size of the NNLO corrections and their effect on the
stability under variations of the renormalization and mass-factorizations
scales are investigated. Except for rather low values of the scales, the
residual uncertainty of the three-loop splitting functions does not lead to
relevant effects for x > 10^-3. Inclusion of the NNLO contributions
considerably reduces the theoretical uncertainty of determinations of the quark
and gluon densities from deep-inelastic structure functions.

</DOC>
<DOC>
<DOCNO> 101776 </DOCNO>
K-area, Hofer metric and geometry of conjugacy classes in Lie groups


  Given a closed symplectic manifold $(M,\omega)$ we introduce a certain
quantity associated to a tuple of conjugacy classes in the universal cover of
the group ${\hbox{\it Ham}} (M,\omega)$ by means of the Hofer metric on
${\hbox{\it Ham}} (M,\omega)$. We use pseudo-holomorphic curves involved in the
definition of the multiplicative structure on the Floer cohomology of a
symplectic manifold $(M,\omega)$ to estimate this quantity in terms of actions
of some periodic orbits of related Hamiltonian flows. As a corollary we get a
new way to obtain Agnihotri-Belkale-Woodward inequalities for eigenvalues of
products of unitary matrices. As another corollary we get a new proof of the
geodesic property (with respect to the Hofer metric) of Hamiltonian flows
generated by certain autonomous Hamiltonians. Our main technical tool is K-area
defined for Hamiltonian fibrations over a surface with boundary in the spirit
of L.Polterovich's work on Hamiltonian fibrations over $S^2$.

</DOC>
<DOC>
<DOCNO> 102776 </DOCNO>
Invitation to higher local fields, Part I, section 11: Generalized class


  Koya's and author's approach to the higher local reciprocity map as a
generalization of the classical class formations approach to the level of
complexes of Galois modules.

</DOC>
<DOC>
<DOCNO> 9433 </DOCNO>
The imprints of nonextensive statistical mechanics in high energy


  To describe high energy collisions one widely uses thermodynamical methods
and concepts which follow the classical Boltzmann-Gibbs (BG) approach. In many
cases, however, either some deviations from the expected behaviour are observed
experimentally or it is known that the conditions necessary for BG to apply are
satisfied only approximately. In other branches of physics where such
situations are ubiquitous, the popular remedy is to resort, instead, to the so
called nonextensive statistics, the most popular example of which is Tsallis
statistics. We shall provide here an overview of possible imprints of
non-extensitivity existing both in high energy cosmic ray physics and in
multiparticle production processes in hadronic collisions, in particular in
heavy ion collisions. Some novel proposition for the interpretation of the
nonextensitivity parameter q present in such circumstances will be discussed in
more detail.

</DOC>
<DOC>
<DOCNO> 121922 </DOCNO>
Simulated Performance of a Germanium Compton Telescope


  To build upon the goals of the upcoming INTEGRAL mission, the next generation
soft gamma-ray (0.2-20 MeV) observatory will require improved sensitivity to
nuclear line emission while maintaining high spectral resolution. We present
the simulated performance of a germanium Compton telescope (GCT) design, which
will allow a factor of ten improvement in sensitivity over INTEGRAL/SPI. We
also discuss a number of issues concerning reconstruction techniques and event
cuts, and demonstrate how these affect the overall performance of the
telescope.

</DOC>
<DOC>
<DOCNO> 170799 </DOCNO>
Quantum Zeno and anti-Zeno effects in the Friedrichs model


  We analyze the short-time behavior of the survival probability in the frame
of the Friedrichs model for different formfactors. We have shown that this
probability is not necessary analytic at the time origin. The time when the
quantum Zeno effect could be observed is found to be much smaller than usually
estimated. We have also studied the anti-Zeno era and have estimated its
duration.

</DOC>
<DOC>
<DOCNO> 68783 </DOCNO>
Spontaneous CP Violation in the Left-Right-Symmetric Model


  We investigate the pattern of CP violation in \Kd, \Bd and \Bs mixing in a
symmetrical \model model with spontaneous CP violation. Performing a careful
analysis of all relevant restrictions on the model's parameters from $\Delta
M_K$, $\Delta M_{B_d}$, $\Delta M_{B_s}$, $\epsilon_K$, the sign of \ee and the
mixing-induced CP asymmetry in \goldd, we find that the mass of the
right-handed charged gauge-boson, $M_2$, is restricted to be in the range 2.75
to 13$ $TeV, and that the mass of the flavour-changing neutral-Higgs bosons,
$M_H$, must be between 10.2 to 14.6$ $TeV. We also find that the model,
although still compatible with present experimental data, cannot accomodate the
SM prediction of large CP violation in \goldd, but, on the other hand, predicts
a large CP-asymmetry of ${\cal O}(40%)$ in \golds. These specific predictions
make it possible to submit the model to a scrupulous test at B factories and
hadron colliders.

</DOC>
<DOC>
<DOCNO> 116660 </DOCNO>
Symmetry Analysis Of Genetic Code And Determinative Degree (in Russian)


  A three-dimensional model of the genetic vocabulary is proposed in terms of
determinative degree, an introduced characteristic of nucleotide, which
reflects absolute difference between purin and pyrimidin bases in one DNA
strand. In the fremework of this model manifest symmetry and group properties
are described. It is proposed to use the determinative degree of codons to
analyze genetic texts, and to explain the biological sense of various
functional regions of DNA.

</DOC>
<DOC>
<DOCNO> 170180 </DOCNO>
Phase-Control of Photoabsorption in Optically Dense Media


  We present a self-consistent theory, as well as an illustrative application
to a realistic system, of phase control of photoabsorption in an optically
dense medium. We demonstrate that, when propagation effects are taken into
consideration, the impact on phase control is significant. Independently of the
value of the initial phase difference between the two fields, over a short
scaled distance of propagation, the medium tends to settle the relative phase
so that it cancels the atomic excitation. In addition, we find some rather
unusual behavior for an optically thin layer.

</DOC>
<DOC>
<DOCNO> 152644 </DOCNO>
On supersymmetric solutions in D = 11 supergravity with Ricci-flat


  An introduction to supersymmetric (SUSY) solutions defined on the product of
Ricci-flat spaces in D= 11 supergravity is presented. The paper contains some
background information: (i) decomposition relations for SUSY equations and (ii)
2^{-k}-splitting theorem that explains the appearance of N = 2^{-k} fractional
supersymmetries. Examples of M2 and M5 branes on the product of two Ricci-flat
spaces are considered and formulae for (fractional) numbers of unbroken SUSY
are obtained.

</DOC>
<DOC>
<DOCNO> 13759 </DOCNO>
Redundancy and synergy arising from correlations in large ensembles


  Multielectrode arrays allow recording of the activity of many single neurons,
from which correlations can be calculated. The functional roles of correlations
can be revealed by the measures of the information conveyed by neuronal
activity; a simple formula has been shown to discriminate the information
transmitted by individual spikes from the positive or negative contributions
due to correlations (Panzeri et al, Proc. Roy. Soc. B., {266}: 1001--1012
(1999)). The formula quantifies the corrections to the single-unit
instantaneous information rate which result from correlations in spike emission
between pairs of neurons. Positive corrections imply synergy, while negative
corrections indicate redundancy. Here, this analysis, previously applied to
recordings from small ensembles, is developed further by considering a model of
a large ensemble, in which correlations among the signal and noise components
of neuronal firing are small in absolute value and entirely random in origin.
Even such small random correlations are shown to lead to large possible synergy
or redundancy, whenever the time window for extracting information from
neuronal firing extends to the order of the mean interspike interval. In
addition, a sample of recordings from rat barrel cortex illustrates the mean
time window at which such `corrections' dominate when correlations are, as
often in the real brain, neither random nor small. The presence of this kind of
correlations for a large ensemble of cells restricts further the time of
validity of the expansion, unless what is decodable by the receiver is also
taken into account.

</DOC>
<DOC>
<DOCNO> 68595 </DOCNO>
Quark Mixings in $SU(6)\times SU(2)_R$ and Suppression of $V_{ub}$


  The quark mixing matrix $V_{CKM}$ is studied in depth on the basis of
superstring inspired $SU(6)\times SU(2)_R$ model with global flavor symmetries.
The sizable mixings between right-handed down-type quark $D^c$ and colored
Higgs field $g^c$ potentially occur but no such mixings in up-type quark
sector. In the model the hierarchical pattern of $V_{CKM}$ is understood
systematically. It is shown that due to large $D^c$-$g^c$ mixings $V_{ub}$ is
naturally suppressed compared to $V_{td}$. It is pointed out that the observed
suppression of $V_{ub}$ is in favor of the presence of $SU(2)_R$ gauge symmetry
but not in accord with generic SU(5) GUT.

</DOC>
<DOC>
<DOCNO> 39802 </DOCNO>
Matter Effects on Neutrino Oscillations in Long Baseline Experiments


  We calculate matter effects on neutrino oscillations relevant for long
baseline experiments. In particular, we compare the results obtained with
constant density along the neutrino path versus results obtained by
incorporating the actual density profiles in the Earth. We study the dependence
of the oscillation signal on both $E/\Delta m^2_{atm}$ and on the angles in the
leptonic mixing matrix. We also comment on the influence of $\Delta m^2_{sol}$
on the oscillations. The results show quantitatively how, as a function of
these input parameters, matter effects can cause significant (25 %) changes in
the oscillation probabilities. An important conclusion is that matter effects
can be useful in amplifying certain neutrino oscillation signals and helping
one to obtain measurements of mixing parameters and the magnitude and sign of
$\Delta m^2_{atm}$.

</DOC>
<DOC>
<DOCNO> 72245 </DOCNO>
WIMP Annual Modulation with Opposite Phase in Late-Infall Halo Models


  We show that in the late-infall model of our galactic halo by P. Sikivie the
expected phase of the annual modulation of a WIMP halo signal in direct
detection experiments is opposite to the one usually expected. If a
non-virialized halo component due to the infall of (collisionless) dark matter
particles cannot be rejected, an annual modulation in a dark matter signal
should be looked for by experimenters without fixing the phase a-priori.
Moreover, WIMP streams coming to Earth from directions above and below the
galactic plane should be expected, with a characteristic pattern of arrival
directions.

</DOC>
<DOC>
<DOCNO> 121439 </DOCNO>
The Formation of a Bound Star Cluster: From the Orion Nebula Cluster to


  (shortened) Direct N-body calculations are presented of the formation of
Galactic clusters using GasEx, which is a variant of the code Nbody6. The
calculations focus on the possible evolution of the Orion Nebula Cluster (ONC)
by assuming that the embedded OB stars explosively drove out 2/3 of its mass in
the form of gas about 0.4 Myr ago. A bound cluster forms readily and survives
for 150 Myr despite additional mass loss from the large number of massive
stars, and the Galactic tidal field. This is the very first time that cluster
formation is obtained under such realistic conditions. The cluster contains
about 1/3 of the initial 10^4 stars, and resembles the Pleiades Cluster to a
remarkable degree, implying that an ONC-like cluster may have been a precursor
of the Pleiades. This scenario predicts the present expansion velocity of the
ONC, which will be measurable by upcoming astrometric space missions (DIVA and
GAIA). These missions should also detect the original Pleiades members as an
associated expanding young Galactic-field sub-population. The results arrived
at here suggest that Galactic clusters form as the nuclei of expanding OB
associations.

</DOC>
<DOC>
<DOCNO> 84530 </DOCNO>
A comment on a paper by Carot et al


  In a recent paper Carot et al. considered carefully the definition of
cylindrical symmetry as a specialisation of the case of axial symmetry. One of
their propositions states that if there is a second Killing vector, which
together with the one generating the axial symmetry, forms the basis of a
two-dimensional Lie algebra, then the two Killing vectors must commute, thus
generating an Abelian group. In this comment a similar result, valid under
considerably weaker assumptions, is recalled: any two-dimensional Lie
transformation group which contains a one-dimensional subgroup whose orbits are
circles, must be Abelian. The method used to prove this result is extended to
apply to three-dimensional Lie transformation groups. It is shown that the
existence of a one-dimensional subgroup with closed orbits restricts the
Bianchi type of the associated Lie algebra to be I (Abelian), II, III, VII_0,
VIII or IX. The relationship between the present approach and that of the
original paper is discussed.

</DOC>
<DOC>
<DOCNO> 85052 </DOCNO>
A new approach to electromagnetic wave tails on a curved spacetime


  We present an alternative method for constructing the exact and approximate
solutions of electromagnetic wave equations whose source terms are arbitrary
order multipoles on a curved spacetime. The developed method is based on the
higher-order Green's functions for wave equations which are defined as
distributions that satisfy wave equations with the corresponding order
covariant derivatives of the Dirac delta function as the source terms. The
constructed solution is applied to the study of various geometric effects on
the generation and propagation of electromagnetic wave tails to first order in
the Riemann tensor. Generally the received radiation tail occurs after a time
delay which represents geometrical backscattering by the central gravitational
source. It is shown that the truly nonlocal wave-propagation correction (the
tail term) takes a universal form which is independent of multipole order. In a
particular case, if the radiation pulse is generated by the source during a
finite time interval, the tail term after the primary pulse is entirely
determined by the energy-momentum vector of the gravitational field source: the
form of the tail term is independent of the multipole structure of the
gravitational source. We apply the results to a compact binary system and
conclude that under certain conditions the tail energy can be a noticeable
fraction of the primary pulse energy. We argue that the wave tails should be
carefully considered in energy calculations of such systems.

</DOC>
<DOC>
<DOCNO> 84413 </DOCNO>
Closed Universes With Black Holes But No Event Horizons As a Solution to


  We show it is possible for the information paradox in black hole evaporation
to be resolved classically. Using standard junction conditions, we attach the
general closed spherically symmetric dust metric to a spacetime satisfying all
standard energy conditions but with a single point future c-boundary. The
resulting Omega Point spacetime, which has NO event horizons, nevertheless has
black hole type trapped surfaces and hence black holes. But since there are no
event horizons, information eventually escapes from the black holes. We show
that a scalar quintessence field with an appropriate exponential potential near
the final singularity would give rise to an Omega Point final singularity.

</DOC>
<DOC>
<DOCNO> 71504 </DOCNO>
Renormalization Group Flow Equations For The Scalar O(N) Theory


  Self-consistent new renormalization group flow equations for an
O(N)-symmetric scalar theory are approximated in next-to-leading order of the
derivative expansion. The Wilson-Fisher fixed point in three dimensions is
analyzed in detail and various critical exponents are calculated.

</DOC>
<DOC>
<DOCNO> 12365 </DOCNO>
Freezing by Monte Carlo Phase-Switch


  We describe a Monte Carlo procedure which allows sampling of the disjoint
configuration spaces associated with crystalline and fluid phases, within a
single simulation. The method utilises biased sampling techniques to enhance
the probabilities of gateway states (in each phase) which are such that a
global switch (to the other phase) can be implemented. Equilibrium
freezing-point parameters can be determined directly; statistical uncertainties
prescribed transparently; and finite-size effects quantified systematically.
The method is potentially quite general; we apply it to the freezing of hard
spheres.

</DOC>
<DOC>
<DOCNO> 123256 </DOCNO>
SW Sextantis in an excited, low state


  We present low-resolution spectrophotometric optical observations of the
eclipsing nova-like cataclysmic variable SW Sex, the prototype of the SW Sex
stars. We observed the system when it was in an unusual low state. The spectrum
is characterized by the presence of strong He II and C IV emission lines as
well as the normal single peaked Balmer emission lines. The radial temperature
profile of the disk follows the expected T ~R^3/4 only in the outer parts and
flattens off inside 0.5 times the white dwarf Roche lobe radius. The single
peaked emission lines originate in a region above the plane of the disk, at the
position of the hot spot.

</DOC>
<DOC>
<DOCNO> 121953 </DOCNO>
The role of Z=0 AGB stars on the early chemical enrichment


  We present theoretical evolutionary models for Z=0 stars in the mass range 4<
M/Mo <8 from the pre-main sequence up to the AGB phase. Contrary to previous
calculations we found that these stars develop normal thermal pulses and third
dredge-up episodes. Special attention is devoted to analyze the chemical
enrichment in the envelope due to the above mechanisms. As a consequence, we
show that these stars become carbon and nitrogen rich. Using different IMFs
proposed in the literature for the Population III stars, we study their
contribution to the pre-galactic chemical enrichment. It is found that Z=0 AGB
stars could significantly contribute to 7Li, 12C and 14N and produce extreme
non-solar 24Mg/25Mg/26Mg ratios. However, the net contribution is very
sensitive to the IMF adopted and to the fraction of primordial matter which
goes into stars.

</DOC>
<DOC>
<DOCNO> 13523 </DOCNO>
Energy spectra and photoluminescence of fractional quantum Hall systems


  The energy spectrum of a two-dimensional electron gas (2DEG) interacting with
a valence-band hole is studied in the high magnetic field limit as a function
of the filling factor nu and the separation d between the electron and hole
layers. For d smaller than the magnetic length lambda, the hole binds one or
more electrons to form neutral (X) or charged (X-) excitons. The low-lying
states can be understood in terms of Laughlin-like correlations among the
constituent charged fermions (electrons and X-). For d comparable to lambda,
the electron-hole interaction is not strong enough to bind a full electron, and
fractionally charged excitons hQEn (bound states of a hole and one or more
Laughlin quasielectrons, QE) are formed. The effect of these excitonic
complexes on the photoluminescence spectrum is studied numerically for a wide
range of values of nu and d.

</DOC>
<DOC>
<DOCNO> 70672 </DOCNO>
Polarizations of J/\psi and \psi' in hadroproduction at Tevatron in the


  We present a calculation for the polarizations of $J/\psi$ and $\psi'$
produced in the hadron collisions at the Fermilab Tevatron. Various color octet
channels including ${}^1S_0^{(8)}$, ${}^3P_J^{(8)}$, and ${}^3S_1^{(8)}$ as
well as contributions from $\chi_{cJ}$ decays are considered in the $k_t$
factorization approach. We find that in a rather wide range of the transverse
momenta of $J/\psi$ and $\psi'$, the production rates could be dominated by the
${}^1S_0^{(8)}$ channel, and the predicted polarizations from the
${}^1S_0^{(8)}$ channel and $\chi_{cJ}$ feeddown contributions are roughly
compatible with the preliminary CDF data. This might provide a possible release
from the conflict between the NRQCD collinear parton model calculations and the
CDF data.

</DOC>
<DOC>
<DOCNO> 99892 </DOCNO>
Loop observables for BF theories in any dimension and the cohomology of


  A generalization of Wilson loop observables for BF theories in any dimension
is introduced in the Batalin-Vilkovisky framework. The expectation values of
these observables are cohomology classes of the space of imbeddings of a
circle. One of the resulting theories discussed in the paper has only trivalent
interactions and, irrespective of the actual dimension, looks like a
3-dimensional Chern-Simons theory.

</DOC>
<DOC>
<DOCNO> 84645 </DOCNO>
Time-Independent Gravitational Fields


  This article reviews, from a global point of view, rigorous results on time
independent spacetimes. Throughout attention is confined to isolated bodies at
rest or in uniform rotation in an otherwise empty universe. The discussion
starts from first principles and is, as much as possible, self-contained.

</DOC>
<DOC>
<DOCNO> 118961 </DOCNO>
Optical and Near Infrared Study of the Cepheus E outflow, a very low


  We present images and spectra of the Cepheus E (Cep E) region at both optical
and infrared wavelengths. Only the brightest region of the southern lobe of the
Cep E outflow reveals optical emission, suggesting that the extinction close to
the outflow source plays an important r\^ole in the observed difference between
the optical and IR morphologies. Cep E is a unique object since it provides a
link between the spectroscopic properties of the optical Herbig-Haro (HH)
objects and those of deeply embedded outflows.

</DOC>
<DOC>
<DOCNO> 40178 </DOCNO>
Light Quark Fragmentation in Polarized Z0 Decays at SLD


  We report results on two physics topics from the SLD experiment at the SLAC
Linear Collider, using our full sample of 550,000 events of the type e+e- -->
Z0 --> q-q(bar). The electron beam was polarized, enabling the quark and
antiquark hemispheres to be tagged in each event. One physics topic is the
first study of rapidities signed such that positive rapidity is along the quark
rather than antiquark direction. Distributions of ordered differences in signed
rapidity between pairs of particles are analyzed, providing the first direct
observation of baryon number ordering along the q-q(bar) axis. The other topic
is the first direct measurement of A_s, the parity-violating coupling of the Z0
to strange quarks, by measuring the left-right forward-backward production
asymmetry in polar angle of the tagged s-quark. We obtain A_s = 0.895 +-
0.066(stat.) +- 0.062(syst.), which is consistent with the Standard Model and
is currently the most precise measurement of this quantity.

</DOC>
<DOC>
<DOCNO> 120279 </DOCNO>
A Broadband X-Ray Study of the Supernova Remnant 3C 397


  We present an X-ray study of the radio bright supernova remnant (SNR) 3C 397
with ROSAT, ASCA, and RXTE. A central X-ray spot seen with the ROSAT
High-Resolution Imager hints at the presence of a pulsar-powered component, and
gives this SNR a composite X-ray morphology. Combined ROSAT and ASCA imaging
show that the remnant is highly asymmetric, with its hard X-ray emission
peaking at the western lobe. The spectrum of 3C 397 is heavily absorbed, and
dominated by thermal emission with emission lines evident from Mg, Si, S, Ar
and Fe. Single-component models fail to describe the spectrum, and at least two
components are required. We use a set of non-equilibrium ionization (NEI)
models (Borkowski et al. in preparation). The temperatures from the soft and
hard components are 0.2 keV and 1.6 keV respectively. The corresponding
ionization time-scales $n_0 t$ ($n_0$ being the pre-shock hydrogen density) are
6 $\times 10^{12}$ cm$^{-3}$ s and 6 $\times$ 10$^{10}$ cm$^{-3}$ s,
respectively. The spectrum obtained with the Proportional Counter Array (PCA)
of RXTE is contaminated by emission from the Galactic ridge, with only $\sim$
15% of the count rate originating from 3C 397 in the 5-15 keV range. The PCA
spectrum allowed us to confirm the thermal nature of the hard X-ray emission. A
third component originating from a pulsar-driven component is possible, but the
contamination of the source signal by the Galactic ridge did not allow us to
find pulsations from any hidden pulsar. We discuss the X-ray spectrum in the
light of two scenarios: a young ejecta-dominated remnant of a core-collapse SN,
and a middle-aged SNR expanding in a dense ISM. Spatially resolved spectroscopy
(with CHANDRA and XMM) is needed to differentiate between the two scenarios,
and address the nature of the mysterious radio-quiet X-ray hot spot.

</DOC>
<DOC>
<DOCNO> 100754 </DOCNO>
Entropy production in quantum spin systems


  We consider a quantum spin system consisting of a finite subsystem connected
to infinite reservoirs at different temperatures. In this setup we define
nonequilibrium steady states and prove that the rate of entropy production in
such states is nonnegative.

</DOC>
<DOC>
<DOCNO> 170670 </DOCNO>
On the LOCC Classification of Bipartite Density Matrices


  We provide a unifying framework for exact, probabilistic, and approximate
conversions by local operations and classical communication (LOCC) between
bipartite states. This framework allows us to formulate necessary and
sufficient conditions for LOCC conversions from pure states to mixed states and
it provides necessary conditions for LOCC conversions between mixed states. The
central idea is the introduction of convex sets for exact, probabilistic, and
approximate conversions, which are closed under LOCC operations and which are
largely characterized by simple properties of pure states.

</DOC>
<DOC>
<DOCNO> 170563 </DOCNO>
A Mach-Zehnder Interferometer for a Two-Photon Wave Packet


  We propose an experiment that permits observation of the de Broglie
two-photon wave packet behavior for a pair of photons, using a Mach-Zehnder
interferometer. It is based on the use of pulsed lasers to generate pairs of
photons via spontaneous parametric down-conversion and the post-selection of
events. It differs from previous realizations by the use of a third
time-correlated photon to engineer the state of the photons. The same technique
can give us which-path information via an ``interaction-free'' experiment and
can be used in other experiments on the foundations of quantum mechanics
related to wave-particle duality and to nonlocality.

</DOC>
<DOC>
<DOCNO> 9290 </DOCNO>
Superconductivity and Antiferromagnetism: Hybridization Impurities in a


  We present the exact solution of a one-dimensional model of a spin-gapped
correlated electron system with hybridization impurities exhibiting both
magnetic and mixed-valence properties. The host supports superconducting
fluctuations, with a spin gap. The localized electrons create a band of
antiferromagnetic spin excitations inside the gap for concentrations x of the
impurities below some critical value x_c. When x = x_c the spin gap closes and
a ferrimagnetic phase appears. This is the first example of an exactly solvable
model with coexisting superconducting and antiferromagnetic fluctuations which
in addition supports a quantum phase transition to a (compensated)
ferrimagnetic phase. We discuss the possible relevance of our results for
experimental systems, in particular the U-based heavy-fermion materials.

</DOC>
<DOC>
<DOCNO> 118445 </DOCNO>
The Properties of Hypernovae: SNe Ic 1998bw, 1997ef, and SN IIn 1997cy


  We discuss the properties of the hyper-energetic Type Ic supernovae (SNe Ic)
1998bw and 1997ef and Type IIn supernova (SN IIn) 1997cy. SNe Ic 1998bw and
1997ef are characterized by their large luminosity and the very broad spectral
features. Their observed properties can be explained if they are very energetic
SN explosions with the kinetic energy of $E_{\rm K} \gsim 1\times10^{52}$ erg,
originating probably from the core collapse of the bare C+O cores of massive
stars ($\sim 30-40$M$_\odot$). At late times, both the light curves and the
spectra suggest that the explosions may have been asymmetric; this may help us
understand the claimed connection with GRB's. The Type IIn SN 1997cy is even
more luminous than SN 1998bw and the light curve declines more slowly than
$^{56}$Co decay. We model such a light curve with circumstellar interaction,
which requires the explosion energy of $\sim 5 \times 10^{52}$ erg. Because
these kinetic energies of explosion are much larger than in normal
core-collapse SNe, we call objects like these SNe "hypernovae". The mass of
$^{56}$Ni in SN 1998bw is estimated to be as large as 0.5 - 0.7 $M_\odot$ from
both the maximum brightness and late time emission spectra, which suggests that
the asymmetry may not be extreme.

</DOC>
<DOC>
<DOCNO> 120192 </DOCNO>
The FIRST Sample of Ultraluminous Infrared Galaxies at High Redshift I.


  We present a new sample of distant ultraluminous infrared galaxies. The
sample was selected from a positional cross--correlation of the IRAS Faint
Source Catalog with the FIRST database. Objects from this set were selected for
spectroscopy by virtue of following the well-known star-forming galaxy
correlation between 1.4 GHz and 60 micron flux, and by being optically faint on
the POSS. Optical identification and spectroscopy were obtained for 108 targets
at the Lick Observatory 3m telescope. Most objects show spectra typical of
starburst galaxies, and do not show the high ionization lines of active
galactic nuclei. The redshift distribution covers 0.1 < z < 0.9, with 13
objects at z > 0.5 and an average redshift of 0.31. K-band images were obtained
at the IRTF, Lick, and Keck observatories in sub-arcsec seeing of all optically
identified targets. About 2/3 of the objects appear to be interacting galaxies,
while the other 1/3 appear to be normal. Nearly all the identified objects have
far-IR luminosities greater than 10^11 L_sun, and ~25% have L_FIR > 10^12
L_sun.

</DOC>
<DOC>
<DOCNO> 11897 </DOCNO>
Fluctuation Theorem for Hamiltonian Systems - Le Chatelier's Principle


  For thermostatted dissipative systems the Fluctuation Theorem gives an
analytical expression for the ratio of probabilities that the time averaged
entropy production in a finite system observed for a finite time, takes on a
specified value compared to the negative of that value. Hitherto it had been
thought that the presence of some thermostatting mechanism was an essential
component of any system which satisfies a Fluctuation Theorem. In the present
paper we show that a Fluctuation Theorem can be derived for purely Hamiltonian
systems, with or without applied dissipative fields.

</DOC>
<DOC>
<DOCNO> 151309 </DOCNO>
Exotic polarizations of D2 branes and oblique vacua of (S)YM$_{2+1}$


  We investigate the oblique vacua in the perturbed 2+1 dimensional gauge
theory living on D2 branes. The string theory dual of these vacua is expected
to correspond to polarizations of the D2 branes into NS5 branes with D4 brane
charge. We perturb the gauge theory by adding fermions masses. In the
nonsupersymmetric case, we also consider the effect of slight variations of the
masses of the scalars. For certain ranges of scalar masses we find oblique
vacua.
  We show that D4 charge is an essential ingredient in understanding D2 -> NS5
polarizations. We find that some of the polarization states which appear as
metastable vacua when D4 charge is not considered are in fact unstable. They
decay by acquiring D4 charge, tilting and shrinking to zero size.

</DOC>
<DOC>
<DOCNO> 11717 </DOCNO>
Coarsening of a Class of Driven Striped Structures


  The coarsening process in a class of driven systems exhibiting striped
structures is studied. The dynamics is governed by the motion of the driven
interfaces between the stripes. When two interfaces meet they coalesce thus
giving rise to a coarsening process in which l(t), the average width of a
stripe, grows with time. This is a generalization of the reaction-diffusion
process A + A -> A to the case of extended coalescing objects, namely, the
interfaces. Scaling arguments which relate the coarsening process to the
evolution of a single driven interface are given, yielding growth laws for
l(t), for both short and long time. We introduce a simple microscopic model for
this process. Numerical simulations of the model confirm the scaling picture
and growth laws. The results are compared to the case where the stripes are not
driven and different growth laws arise.

</DOC>
<DOC>
<DOCNO> 100855 </DOCNO>
Ordering pure braid groups on closed surfaces


  We prove that the pure braid groups on closed, orientable surfaces are
bi-orderable, and that the pure braid groups on closed, non-orientable surfaces
have generalized torsion, thus they are not bi-orderable.

</DOC>
<DOC>
<DOCNO> 10549 </DOCNO>
Extremal Paths on a Random Cayley Tree


  We investigate the statistics of extremal path(s) (both the shortest and the
longest) from the root to the bottom of a Cayley tree. The lengths of the edges
are assumed to be independent identically distributed random variables drawn
from a distribution \rho(l). Besides, the number of branches from any node is
also random. Exact results are derived for arbitrary distribution \rho(l). In
particular, for the binary {0,1} distribution
\rho(l)=p\delta_{l,1}+(1-p)\delta_{l,0}, we show that as p increases, the
minimal length undergoes an unbinding transition from a `localized' phase to a
`moving' phase at the critical value, p=p_c=1-b^{-1}, where b is the average
branch number of the tree. As the height n of the tree increases, the minimal
length saturates to a finite constant in the localized phase (p<p_c), but
increases linearly as v_{min}(p)n in the moving phase (p>p_c) where the
velocity v_{min}(p) is determined via a front selection mechanism. At p=p_c,
the minimal length grows with n in an extremely slow double logarithmic
fashion. The length of the maximal path, on the other hand, increases linearly
as v_{max}(p)n for all p. The maximal and minimal velocities satisfy a general
duality relation, v_{min}(p)+v_{max}(1-p)=1, which is also valid for directed
paths on finite-dimensional lattices.

</DOC>
<DOC>
<DOCNO> 71160 </DOCNO>
Fermions, Gauge Theories, and the Sinc Function Representation for


  We extend our new approach for numeric evaluation of Feynman diagrams to
integrals that include fermionic and vector propagators. In this initial
discussion we begin by deriving the Sinc function representation for the
propagators of spin-1/2 and spin-1 fields and exploring their properties. We
show that the attributes of the spin-0 propagator which allowed us to derive
the Sinc function representation for scalar field Feynman integrals are shared
by fields with non-zero spin. We then investigate the application of the Sinc
function representation to simple QED diagrams, including first order
corrections to the propagators and the vertex.

</DOC>
<DOC>
<DOCNO> 102893 </DOCNO>
Optimal solvability for the Dirichlet and Neumann problem in dimension


  We show existence and uniqueness for the solutions of the regularity and the
Neumann problems for harmonic functions on Lipschitz domains with data in the
Hardy spaces H^p, p>2/3, where This in turn implies that solutions to the
Dirichlet problem with data in the Holder class C^{1/2}(\partial D) are
themselves in C^{1/2}(D). Both of these results are sharp. In fact, we prove a
more general statement regarding the H^p solvability for divergence form
elliptic equations with bounded measurable coefficients.
  We also prove similar solvability result for the regularity and Dirichlet
problem for the biharmonic equation on Lipschitz domains.

</DOC>
<DOC>
<DOCNO> 67715 </DOCNO>
Mass modification of D-meson at finite density in QCD sum rule


  We evaluate the mass shift of isospin-averaged D-meson in the nuclear medium.
Borel-transformed QCD sum rules are used to describe an interaction between the
D-meson and a nucleon by taking into account all the lowest dimension-4
operators in the operator product expansion (OPE). We find at normal matter
density the D-meson mass shift is about 10 times (\sim 50 MeV) larger than that
of J/\psi. This originates from the fact that the dominant contribution in the
OPE for the D-meson is the nucleon matrix element of m_c\bar{q}q, where m_c is
the charm-quark mass and q denotes light quarks. We also discuss that the mass
shift of the D-meson in nuclear matter may cause the level crossings of the
charmonium states and the D\bar{D} threshold. This suggests an additional
mechanism of the J/\psi suppression in high energy heavy-ion collisions.

</DOC>
<DOC>
<DOCNO> 178928 </DOCNO>
Coupled Dyson-Schwinger Equations and Effects of Self-Consistency


  Using the $\sigma -\omega$ model as an effective tool, the effects of
self-consistency are studied in some detail. A coupled set of Dyson-Schwinger
equations for the renormalized baryon and meson propagators in the $\sigma
-\omega$ model is solved self-consistently according to the dressed
Hartree-Fock scheme, where the hadron propagators in both the baryon and meson
self-energies are required to also satisfy this coupled set of equations. It is
found that the self-consistency affects the baryon spectral function
noticeably, if only the interaction with $\sigma$ mesons is considered.
However, there is a cancellation between the effects due to the $\sigma$ and
$\omega$ mesons and the additional contribution of $\omega$ mesons makes the
above effect insignificant. In both the $\sigma$ and $\sigma -\omega$ cases the
effects of self-consistency on meson spectral function are perceptible, but
they can nevertheless be taken account of without a self-consistent
calculation. Our study indicates that to include the meson propagators in the
self-consistency requirement is unnecessary and one can stop at an early step
of an iteration procedure to obtain a good approximation to the fully
self-consistent results of all the hadron propagators in the model, if an
appropriate initial input is chosen. Vertex corrections and their effects on
ghost poles are also studied.

</DOC>
<DOC>
<DOCNO> 13952 </DOCNO>
Inhomogeneous Pairing in Highly Disordered s-wave Superconductors


  We study a simple model of a two-dimensional s-wave superconductor in the
presence of a random potential in the regime of large disorder. We first use
the Bogoliubov-de Gennes (BdG) approach to show that, with increasing disorder
the pairing amplitude becomes spatially inhomogeneous, and the system cannot be
described within conventional approaches for studying disordered
superconductors which assume a uniform order parameter. In the high disorder
regime, we find that the system breaks up into superconducting islands (with
large pairing amplitude) separated by an insulating sea. We show that this
inhomogeneity has important implications for the physical properties of this
system, such as superfluid density and the density of states. We find that a
finite spectral gap persists in the density of states for all values of
disorder and we provide a detailed understanding of this remarkable result. We
next generalize Anderson's idea of the pairing of exact eigenstates to include
an inhomogeneous pairing amplitude, and show that it is able to qualitatively
capture many of the nontrivial features of the full BdG analysis. Finally, we
study the transition to a gapped insulating state driven by the quantum phase
fluctuations about the inhomogeneous superconducting state.

</DOC>
<DOC>
<DOCNO> 39655 </DOCNO>
The DELPHI Silicon Tracker in the global pattern recognition


  ALEPH and DELPHI were the first experiments operating a silicon vertex
detector at LEP. During the past 10 years of data taking the DELPHI Silicon
Tracker was upgraded three times to follow the different tracking requirements
for LEP 1 and LEP 2 as well as to improve the tracking performance. Several
steps in the development of the pattern recognition software were done in order
to understand and fully exploit the silicon tracker information. This article
gives an overview of the final algorithms and concepts of the track
reconstruction using the Silicon Tracker in DELPHI.

</DOC>
<DOC>
<DOCNO> 83198 </DOCNO>
A characterization of the set of fixed points of the Quicksort


  The limiting distribution \mu of the normalized number of key comparisons
required by the Quicksort sorting algorithm is known to be the unique fixed
point of a certain distributional transformation T -- unique, that is, subject
to the constraints of zero mean and finite variance. We show that a
distribution is a fixed point of T if and only if it is the convolution of \mu
with a Cauchy distribution of arbitrary center and scale. In particular,
therefore, \mu is the unique fixed point of T having zero mean.

</DOC>
<DOC>
<DOCNO> 71451 </DOCNO>
CMB with Quintessence: Analytic Approach and CMBFAST


  A particular kind of quintessence is considered, with equation of motion
$p_Q/\rho_Q = -1$, corresponding to a cosmological term with time-dependence
$\Lambda(t) = \Lambda(t_0) (R(t_0)/R(t))^{P}$ which we examine initially for $0
\leq P < 3$. Energy conservation is imposed, as is consistency with big-bang
nucleosynthesis, and the range of allowed $P$ is thereby much restricted to $0
\leq P < 0.2$. The position of the first Doppler peak is computed analytically
and the result combined with analysis of high-Z supernovae to find how values
of $\Omega_m$ and $\Omega_{\Lambda}$ depend on $P$. Some comparison is made to
the CMBFAST public code.

</DOC>
<DOC>
<DOCNO> 12231 </DOCNO>
Magnetic qubits as hardware for quantum computers


  We propose two potential realisations for quantum bits based on nanometre
scale magnetic particles of large spin S and high anisotropy molecular
clusters. In case (1) the bit-value basis states |0> and |1> are the ground and
first excited spin states Sz = S and S-1, separated by an energy gap given by
the ferromagnetic resonance (FMR) frequency. In case (2), when there is
significant tunnelling through the anisotropy barrier, the qubit states
correspond to the symmetric, |0>, and antisymmetric, |1>, combinations of the
two-fold degenerate ground state Sz = +- S. In each case the temperature of
operation must be low compared to the energy gap, \Delta, between the states
|0> and |1>. The gap \Delta in case (2) can be controlled with an external
magnetic field perpendicular to the easy axis of the molecular cluster. The
states of different molecular clusters and magnetic particles may be entangled
by connecting them by superconducting lines with Josephson switches, leading to
the potential for quantum computing hardware.

</DOC>
<DOC>
<DOCNO> 119332 </DOCNO>
How Galaxies Disguise Their Ages


  We calculate the contribution to Balmer line indices from far ultraviolet
component sources. We find that this is significant, and may lead to
identification of spurious age differences of the order of a total span of
$\sim 6$ Gyrs or $\sim 15%$ size bursts observed a few Gyrs after star
formation stops. We suggest that claims for intermediate age populations in
early-type galaxies may need to be reconsidered in the light of this new
evidence.

</DOC>
<DOC>
<DOCNO> 7931 </DOCNO>
On the Possibility of Abnormally Intense Radiation Due to the Rotation


  The abnormally intense radiation due to the uniform rotation of electron
around the equatorial plane of a dielectric sphere is obtained. It takes place
when the sphere surface is at a specific distance from the electron orbit and
when the Cherenkov condition for electron and the matter of the sphere is
satisfied.

</DOC>
<DOC>
<DOCNO> 85286 </DOCNO>
Naked singularities and quantum gravity


  There are known models of spherical gravitational collapse in which the
collapse ends in a naked shell-focusing singularity for some initial data. If a
massless scalar field is quantized on the classical background provided by such
a star, it is found that the outgoing quantum flux of the scalar field diverges
in the approach to the Cauchy horizon. We argue that the semiclassical
approximation (i.e. quantum field theory on a classical curved background) used
in these analyses ceases to be valid about one Planck time before the epoch of
naked singularity formation, because by then the curvature in the central
region of the star reaches Planck scale. It is shown that during the epoch in
which the semiclassical approximation is valid, the total emitted energy is
about one Planck unit, and is not divergent. We also argue that back reaction
in this model does not become important so long as gravity can be treated
classically. It follows that the further evolution of the star will be
determined by quantum gravitational effects, and without invoking quantum
gravity it is not possible to say whether the star radiates away on a short
time scale or settles down into a black hole state.

</DOC>
<DOC>
<DOCNO> 11700 </DOCNO>
Time-reversal symmetry breaking at Josephson tunnel junctions of purely


  We study spontaneous time-reversal symmetry breaking at Josephson tunnel
junctions of d-wave superconductors in the absence of subdominant components of
the order parameter. For tunnel junctions, when the orientation is close to
0/45 (for which a gap lobe points towards the junction on one side and a gap
node on the other), the mechanism of the symmetry breaking is the splitting of
midgap states (MGS) by spontaneous establishment of a phase difference
$\phi=\pm \pi/2$ across the junction. This occurs for transparencies
$D\gg\xi_0/\lambda$ and temperatures $k_BT\ll D\Delta_0$, where $\xi_0$ is the
coherence length, $\lambda$ is the penetration depth, and $\Delta_0$ is the
maximum energy gap. On the other hand. tunnel junctions with
$D\ll\xi_0/\lambda$ effectively behave as surfaces, for which the mechanism of
symmetry breaking is self-induced Doppler shifts of MGS. For this instability,
we calculate the phase transition temperature
$k_BT_{TRSB}=(1/6)(\xi_0/\lambda)\Delta_0$ and show that the spatial shape of
the gap is unimportant.

</DOC>
<DOC>
<DOCNO> 11770 </DOCNO>
Highly localized clustering states in a granular gas driven by a


  An ensemble of inelastically colliding grains driven by a vibrating wall in
2D exhibits density clustering. Working in the limit of nearly elastic
collisions and employing granular hydrodynamics, we predict, by a marginal
stability analysis, a spontaneous symmetry breaking of the extended clustering
state (ECS). 2D steady-state solutions found numerically describe localized
clustering state (LCSs). Time-dependent granular hydrodynamic simulations show
that LCSs can develop from natural initial conditions. The predicted
instability should be observable in experiment.

</DOC>
<DOC>
<DOCNO> 122118 </DOCNO>
Shear turbulence beneath the solar tachocline


  Helioseismic inversions of the Sun's internal angular velocity profile show
that the rotation changes from differential in latitude in the convection zone
to almost uniform in the radiative region below. The transition occurs in a
thin layer, the tachocline, which is the seat of strong shear in the vertical
direction. In this Note we examine whether this rotation profile can lead to
shear turbulence at the top of the radiation zone. By using the standard solar
model, we show that such turbulence can be generated only in a narrow region
0.695R_sun < r < 0.713R_sun at the equator and even in narrower layers at
higher latitudes. We conclude that the turbulence generated by this vertical
shear is unlikely to play a significant role in the transport of matter and
angular momentum, and that other mechanisms must be invoked to achieve this.

</DOC>
<DOC>
<DOCNO> 70945 </DOCNO>
New Physics, precision electroweak data and an upper bound on higgs mass


  In this paper we express the effect of new physics on gauge boson self energy
corrections through non-renormalizable dimension six operators. Using the
precision electroweak data we then determine a lower bound on the scale ${\l}$
associated with the underlying new physics. The lower bound on $\l$ is then
used to derive an upper bound on $m_h$ through the triviality relation.

</DOC>
<DOC>
<DOCNO> 123186 </DOCNO>
Chandra Observations of M31


  As part of the Chandra GTO program we are monitoring and surveying M31 using
the HRC and ACIS cameras. These observations have resolved the nuclear X-ray
source into five separate sources, one of which is very soft and may (or may
not!) be associated with the central super-massive black hole. In addition, the
superb spatial resolution and low scattering of the Chandra telescope allows us
to unambiguously resolve the diffuse emission from the point sources. This
emission is clearly softer than the point sources, and also increases with
temperature radially. The monitoring nature of the observations allows detailed
study of the variability of the point sources.

</DOC>
<DOC>
<DOCNO> 119868 </DOCNO>
Tentative Detection of Galaxy Spin Correlations in the Tully Catalogue


  We report a tentative detection of spin correlations in the Tully catalogue
of nearby galaxies. We define a simple but nontrivial spin correlation
function, and find an analytic estimate of it in the frame of the linear
perturbation theory. Then, we present the observed spin correlation signal from
the Tully galaxies with error bars. The three dimensional spin correlation
turns out to be significant at the 97% confidence level, detected out to a few
$h^{-1}$ Mpc. This observed correlation is consistent with the theoretical
prediction based on the gravitational instability picture of galaxy formation.
An analysis of systematic errors is also presented. The observed strength of
correlation may be sufficient to significantly affect blank field of weak
lensing searches.

</DOC>
<DOC>
<DOCNO> 120105 </DOCNO>
Cluster Tempreature Evolution: The Mass-Temperature Relation


  Evolution of the cluster temperature function is extremely sensitive to the
mean matter density of the universe. Current measurements based on cluster
temperature surveys indicate that Omega_M ~ 0.3 with a 1-sigma statistical
error ~0.1, but the systematic errors in this method are of comparable size.
Many more high-z cluster temperatures will be arriving from Chandra and XMM in
the near future. In preparation for future cluster temperature surveys, this
paper analyses the cluster mass-temperature relation, with the intention of
identifying and reducing the systematic errors it introduces into measurements
of cosmological parameters. We show that the usual derivation of this relation
from spherical top-hat collapse is physically inconsistent and propose a more
realistic derivation based on a hierarchical merging model that more faithfully
reflects the gradual ceasing of cluster evolution in a low-Omega_M universe. We
also analyze the effects of current systematic uncertainties in the M-T
relation and show that they introduce a systematic uncertainty of ~0.1 in the
best-fitting Omega_M. Future improvements in the accuracy of the M-T relation
will most likely come from comparisons of predicted cluster temperature
functions with temperature functions derived directly from large-scale
structure simulations.

</DOC>
<DOC>
<DOCNO> 85528 </DOCNO>
The gravitational wave symphony of the Universe


  The new millennium will see the upcoming of several ground-based
interferometric gravitational wave antennas. Within the next decade a
space-based antenna may also begin to observe the distant Universe. These
gravitational wave detectors will together operate as a network taking data
continuously for several years, watching the transient and continuous phenomena
occurring in the deep cores of astronomical objects and dense environs of the
early Universe where gravity was extremely strong and highly non-linear. The
network will listen to the waves from rapidly spinning non-axisymmetric neutron
stars, normal modes of black holes, binary black hole inspiral and merger,
phase transitions in the early Universe, quantum fluctuations resulting in a
characteristic background in the early Universe. The gravitational wave
antennas will open a new window to observe the dark Universe unreachable via
other channels of astronomical observations.

</DOC>
<DOC>
<DOCNO> 120273 </DOCNO>
Power Spectrum of the density of cold atomic gas in the Galaxy towards


  We have obtained the power spectral description of the density and opacity
fluctuations of the cold HI gas in the Galaxy towards Cas A, and Cygnus A. We
have employed a method of deconvolution, based on CLEAN, to estimate the true
power spectrum of optical depth of cold HI gas from the observed distribution,
taking into account the finite extent of the background source and the
incomplete sampling of optical depth over the extent of the source. We
investigate the nature of the underlying spectrum of density fluctuations in
the cold HI gas which would be consistent with that of the observed HI optical
depth fluctuations. These power spectra for the Perseus arm towards Cas A, and
for the Outer arm towards Cygnus A have a slope of 2.75 +/- 0.25 (3sigma
error). The slope in the case of the Local arm towards Cygnus A is 2.5, and is
significantly shallower in comparison. The linear scales probed here range from
0.01 to 3 pc. We discuss the implications of our results, the non-Kolmogorov
nature of the spectrum, and the observed HI opacity variations on small
transverse scales.

</DOC>
<DOC>
<DOCNO> 170617 </DOCNO>
Quantum information theory


  Quantum information theory is the study of the achievable limits of
information processing within quantum mechanics. Many different types of
information can be accommodated within quantum mechanics, including classical
information, coherent quantum information, and entanglement. Exploring the rich
variety of capabilities allowed by these types of information is the subject of
quantum information theory, and of this Dissertation. In particular, I
demonstrate several novel limits to the information processing ability of
quantum mechanics. Results of especial interest include: the demonstration of
limitations to the class of measurements which may be performed in quantum
mechanics; a capacity theorem giving achievable limits to the transmission of
classical information through a two-way noiseless quantum channel; resource
bounds on distributed quantum computation; a new proof of the quantum noiseless
channel coding theorem; an information-theoretic characterization of the
conditions under which quantum error-correction may be achieved; an analysis of
the thermodynamic limits to quantum error-correction, and new bounds on channel
capacity for noisy quantum channels.

</DOC>
<DOC>
<DOCNO> 69365 </DOCNO>
Loops and legs beyond perturbation theory


  Within the non-perturbative 1/N expansion, we discuss numerical methods for
calculating multi-loop Feynman graph needed to derive physical scattering
amplitudes. We apply higher order 1/N methods to the scalar sector of the
standard model, and show the existence of a mass saturation effect. The mass
saturation has direct implications for future searches at the LHC and at
possible muon colliders.

</DOC>
<DOC>
<DOCNO> 152609 </DOCNO>
Response of an electron system to a periodic potential


  We give a quantum field theoretical treatment of a one dimensional electron
system with a fixed chemical potential $\mu$. The non-perturbative Lindhard
response function is found for an electron system in a sinusoidal potential.

</DOC>
<DOC>
<DOCNO> 71151 </DOCNO>
Solar and Atmospheric Neutrino Oscillations


  I review the status of neutrino masses and mixings in the light of the solar
and atmospheric neutrino data in the framework of two--, three-- and four
neutrino mixing.

</DOC>
<DOC>
<DOCNO> 152210 </DOCNO>
The stability of vacua in two-dimensional gauge theory


  We discuss the stability of vacua in two-dimensional gauge theory for any
simple, simply connected gauge group. Making use of the representation of a
vacuum in terms of a Wilson line at infinity, we determine which vacua are
stable against pair production of heavy matter in the adjoint of the gauge
group. By calculating correlators of Wilson loops, we reduce the problem to a
problem in representation theory of Lie groups, that we solve in full
generality.

</DOC>
<DOC>
<DOCNO> 70404 </DOCNO>
Cosmological constraints on a Peccei-Quinn flatino as the lightest


  In an interesting class of models, non-renormalizable terms of the
superpotential are responsible for the spontanteous breaking of Peccei-Quinn
(PQ) symmetry as well as the generation of the $\mu$ term. The flaton fields
which break PQ symmetry are accompanied by flatinos, and the lightest flatino
(the LSP) can be the stable, while the decay of the lightest neutralino (the
NLSP) might be visible at colliders with a low axion scale. We examine the
cosmology of these models, involving thermal inflation just after the PQ phase
transition. The branching ratio of flatons into axions must be small so as not
to interfere with nucleosynthesis, and flatons must not decay into the LSP or
it will be over-abundant. We explore a simple model,with light flatons which
can decay into $Z$ or $W$ bosons, or into a light Higgs ($h^0$) plus a $Z$
boson, to show that such features can be realized in a wide range of parameter
space. The mass of the NLSP can be as low as $(m_{h^0}+m_Z)/2$, with an axion
scale of order $10^{10}$ GeV and a final reheat temperature typically of order
$10\GeV$. Then, the flatino LSP is a good dark matter candidate because the
reheat temperature can be high enough to allow its production from the decay of
the thermalized LSP, while low enough to prevent its overproduction from the
decay of sfermions.

</DOC>
<DOC>
<DOCNO> 117726 </DOCNO>
Magnetic field and unstable accretion during AM Herculis low states


  A study of AM Her low states in September 1990 and 1991 and June-July 1997 is
reported from a coordinated campaign with observations obtained at the
Haute-Provence observatory, at the 6-m telescope of the Special Astrophysical
Observatory and at the 2.6m and 1.25m telescopes of the Crimean observatory.
Spectra obtained at different dates when the source was in low states at a
comparable V magnitude, show the presence of strong Zeeman absorption features
and marked changes in emission lines with a day-to-day reappearance of the HeII
(4686\AA) emission lines in 1991. Despite this variability, the magnetic field
inferred from the fitting of the absorption spectrum with Zeeman hydrogen
splitting, is remarkably constant with a best value of (12.5$\pm$0.5)MG.
Detailed analysis of the UBVRI light curves shows the presence of repetitive
moderate amplitude ($\sim$ 0.3-0.5 mag) flares predominantly red in colour.
These flares are attributed to small accretion events and are compared to the
large ($\sim$ 2 mag.) blue flare reported by Shakhovskoy et al. (1993). We
suggest that the general flaring activity observed during the low states is
generated by accretion events. The different characteristics of the flares
(colour and polarization) are the results of different shock geometries
depending on the net mass accretion flux.

</DOC>
<DOC>
<DOCNO> 40094 </DOCNO>
Kin: the optimal variable for CP-violation


  We advocate the use of an optimal variable to demontrate CP violation. This
variable, named the Kin variable, provides a means to visualize graphically CP
violation, to pin point the most statistically powerful events, and to combine
several channels and experiments. For the B0->J/PSiKs channel, its use leads to
a straightforward measurement of sin(2beta).

</DOC>
<DOC>
<DOCNO> 84782 </DOCNO>
Slowly rotating voids in cosmology


  We consider a spacetime consisting of an empty void separated from an almost
Friedmann-Lema\^\i tre-Robertson-Walker (FLRW) dust universe by a spherically
symmetric, slowly rotating shell which is comoving with the cosmic dust. We
treat in a unified manner all types of the FLRW universes. The metric is
expressed in terms of a constant characterizing the angular momentum of the
shell, and parametrized by the comoving radius of the shell. Treating the
rotation as a first order perturbation, we compute the dragging of inertial
frames as well as the apparent motion of distant stars within the void.
Finally, we discuss, in terms of in principle measurable quantities, 'Machian'
features of the model.

</DOC>
<DOC>
<DOCNO> 101542 </DOCNO>
A Kohno-Drinfeld theorem for quantum Weyl groups


  Let g be a complex, simple Lie algebra and t a Cartan subalgebra of g. A new
unitary, flat connection on t with values in any finite-dimensional g-module V
and simple poles along the root hyperplanes was recently introduced by J.
Millson and myself. This connection depends upon a complex parameter h and I
conjectured that its monodromy is equivalent to the quantum Weyl group
representation of the braid group of type g defined by Lusztig,
Kirillov-Reshetikhin and Soibelman via the quantum group U_{h}g. In this paper,
I prove this conjecture for g=sl_{n}.

</DOC>
<DOC>
<DOCNO> 118270 </DOCNO>
ISO-SWS spectra of galaxies: continuum and features


  We present an inventory of mid-infrared spectral features detected in high
resolution 2.4 to 45um ISO-SWS spectra of the galaxies M82, NGC253, Circinus,
NGC1068, and the 30Doradus region of the LMC. We discuss their identifications
and highlight possible relations between these features and the physical state
of the interstellar medium in galaxies. In the 5--13 um region, emission from
unidentified infrared bands (UIBs), usually ascribed to aromatic molecules, and
apparent silicate absorption dominate the spectrum. We demonstrate the danger
of overestimating the amount of silicate absorption by comparing the spectrum
of M82 to the (absorption free) spectrum of the reflection nebula NGC7023. No
strong silicate absorption is present in M82. The (very small grain) dust
continuum under the UIB emission in our starburst templates can be modeled by a
simple power law, starting at wavelengths between 8 and 9um. The spectra are
valuable templates for future mid-infrared missions. We smooth our data to
simulate low resolution spectra as obtained with ISOCAM-CVF, ISOPHOT-S, and in
the future with the low resolution mode of SIRTF-IRS, and use our high spectral
resolution information to highlight possible identification problems at low
resolving power that are caused by coincidences of lines and features.

</DOC>
<DOC>
<DOCNO> 9386 </DOCNO>
Andreev Conductance of Chaotic and Integrable Quantum Dots


  We examine the voltage V and magnetic field B dependent Andreev conductance
of a chaotic quantum dot coupled via point contacts to a normal metal and a
superconductor. In the case where the contact to the superconductor dominates,
we find that the conductance is consistent with the dot itself behaving as a
superconductor-- it appears as though Andreev reflections are occurring locally
at the interface between the normal lead and the dot. This is contrasted
against the behaviour of an integrable dot, where for a similar strong coupling
to the superconductor, no such effect is seen. The voltage dependence of the
Andreev conductance thus provides an extremely pronounced quantum signature of
the nature of the dot's classical dynamics. For the chaotic dot, we also study
non-monotonic re-entrance effects which occur in both V and B.

</DOC>
<DOC>
<DOCNO> 84487 </DOCNO>
Gauge-invariant gravitational perturbations of maximally symmetric


  Gravitational perturbations of anti-deSitter spacetime play important roles
in AdS/CFT correspondence and the brane world scenario. In this paper, we
develop a gauge-invariant formalism of gravitational perturbations of maximally
symmetric spacetimes including anti-deSitter spacetime. Existence of
scalar-type master variables is shown and the corresponding master equations
are derived.

</DOC>
<DOC>
<DOCNO> 13683 </DOCNO>
Tunneling of Bloch electrons through vacuum barrier


  Tunneling of Bloch electrons through a vacuum barrier introduces new physical
effects in comparison with the textbook case of free (plane wave) electrons.
For the latter, the exponential decay rate in the vacuum is minimal for
electrons with the parallel component of momentum ${\bf k}_\parallel=0$, and
the prefactor is defined by the electron momentum component in the normal to
the surface direction. However, the decay rate of Bloch electrons may be
minimal at an arbitrary ${\bf k}_\parallel$ (``hot spots''), and the prefactor
is determined by the electron's group velocity, rather than by its
quasimomentum.

</DOC>
<DOC>
<DOCNO> 70365 </DOCNO>
Modified Wandzura-Wilczek Relation with the Nachtmann Variable


  If one retains M^2/Q^2 terms in the kinematics, the Nachtmann variable \xi
seems to be more appropriate to describe deep inelastic lepton-nucleon
scattering. Up to the first power of M^2/Q^2, a modified Wandzura-Wilczek
relation with respect to \xi was derived. Kinematical correction factors are
given as functions of \xi and Q^2. A comparison of the modified g_2^WW(\xi) and
original g_2^WW(x) with the most recent g_2 data is shown.

</DOC>
<DOC>
<DOCNO> 119649 </DOCNO>
The infrared counterpart of the Z source GX5-1


  We have obtained UKIRT infrared observations of the field of the bright
Galactic Z source GX5-1. From an astrometric plate solution tied to Tycho-ACT
standards we have obtained accurate positions for the stars in our field which,
combined with an accurate radio position, have allowed us to identify the
probable infrared counterpart of GX5-1. Narrow-band photometry marginally
suggests excess Br-gamma emission in the counterpart, supporting its
association with an accretion-disc source. No significant variability is
observed in a limited number of observations. We compare the H and K magnitudes
with those of other Z sources, and briefly discuss possible sources of infrared
emission in these systems.

</DOC>
<DOC>
<DOCNO> 121112 </DOCNO>
Chandra X-ray Observations of Pictor A: High Energy Cosmic Rays in a


  We report X-ray observations of the nearby, powerful radio galaxy Pictor A
with the Chandra Observatory and optical and near uv observations of its
western radio hot spot with the Hubble Space Telescope. X-ray emission is
detected from the nucleus, a 1.9 arcmin (110 kpc) long jet to the west of the
nucleus, the western radio hot spot some 4.2 arcmin (240 kpc) from the nucleus,
and the eastern radio lobe. The morphology of the western hot spot is
remarkably similar to that seen at radio and optical wavelengths, where the
emission is known to be synchrotron radiation. The X-ray spectrum of the hot
spot is well described by an absorbed power law with photon index \Gamma = 2.07
(+/- 0.11). The X-ray jet coincides with a weak radio jet and is laterally
extended by \simeq 2.0 arcsec (1.9 kpc). The observed jet is up to \simeq 15
times brighter in X-rays than any counter jet, a difference ascribed to
relativistic boosting as the western radio lobe is probably the closer. The
jet's spectrum is well modelled by an absorbed power law with \Gamma = 1.94
(+0.43/-0.49) and poorly fitted by a Raymond-Smith thermal plasma model.
  (Abstract truncated).

</DOC>
<DOC>
<DOCNO> 11343 </DOCNO>
Frequencies and Damping rates of a 2D Deformed Trapped Bose gas above


  We derive the equation of motion for the velocity fluctuations of a 2D
deformed trapped Bose gas above the critical temperature in the hydrodynamical
regime. From this equation, we calculate the eigenfrequencies for a few
low-lying excitation modes. Using the method of averages, we derive a
dispersion relation in a deformed trap that interpolates between the
collisionless and hydrodynamic regimes. We make use of this dispersion relation
to calculate the frequencies and the damping rates for monopole and quadrupole
mode in both the regimes. We also discuss the time evolution of the wave packet
width of a Bose gas in a time dependent as well as time independent trap.

</DOC>
<DOC>
<DOCNO> 178913 </DOCNO>
Nuclear Shadowing and the Optics of Hadronic Fluctuations


  A coordinate space description of shadowing in deep-inelastic lepton-nucleus
scattering is presented. The picture in the laboratory frame is that of
quark-gluon fluctuations of the high-energy virtual photon, propagating
coherently over large light-cone distances in the nuclear medium. We discuss
the detailed dependence of the coherence effects on the invariant mass of the
fluctuation. We comment on the issue of possible saturation in the shadowing
effects at very small Bjorken-$x$.

</DOC>
<DOC>
<DOCNO> 151245 </DOCNO>
N=1 and N=2 supersymmetric non-abelian Born-Infeld actions from


  New non-abelian supersymmetric generalizations of the four-dimensional
Born-Infeld action are constructed in N=1 and N=2 superspace, to all orders in
the gauge superfield strength. The proposed actions are dictated by simple
(manifestly supersymmetric and gauge-covariant) non-linear constraints.

</DOC>
<DOC>
<DOCNO> 68941 </DOCNO>
New positivity bounds on polarized parton distributions in multicolored


  We derive new positivity bounds on spin-dependent parton distributions in
multicolored QCD. They are stronger than Soffer inequality. We check that the
new inequalities are stable under one-loop DGLAP evolution to higher
normalization points.

</DOC>
<DOC>
<DOCNO> 170300 </DOCNO>
Addition on a Quantum Computer


  A new method for computing sums on a quantum computer is introduced. This
technique uses the quantum Fourier transform and reduces the number of qubits
necessary for addition by removing the need for temporary carry bits. This
approach also allows the addition of a classical number to a quantum
superposition without encoding the classical number in the quantum register.
This method also allows for massive parallelization in its execution.

</DOC>
<DOC>
<DOCNO> 122749 </DOCNO>
Supersonic water masers in 30 Doradus


  We report on extremely high velocity molecular gas, up to -80 km/s relative
to the ambient medium, in the giant star-formation complex 30 Doradus in the
Large Magellanic Cloud (LMC), as observed in new 22 GHz H2O maser emission
spectra obtained with the Mopra radio telescope. The masers may trace the
velocities of protostars, and the observed morphology and kinematics indicate
that current star formation occurs near the interfaces of colliding
stellar-wind blown bubbles. The large space velocities of the protostars and
associated gas could result in efficient mixing of the LMC. A similar mechanism
in the Milky Way could seed the galactic halo with relatively young stars and
gas.

</DOC>
<DOC>
<DOCNO> 12525 </DOCNO>
Acoustic wave propagation in an one-dimensional layered system


  Propagation of acoustic waves in an one-dimensional water duct containing
many air filled blocks is studied by the transfer matrix formalism. Energy
distribution and interface vibration of the air blocks are computed. For
periodic arrangement band structure and transmission rate are calculated
analytically, whereas the Lyapunov exponent and its variance are computed
numerically for random situations. A distinct collective behavior for localized
waves is found. The results are also compared with optical situations.

</DOC>
<DOC>
<DOCNO> 150351 </DOCNO>
The effect of different regulators in the non-local field-antifield


  Recently it was shown how to regularize the Batalin-Vilkovisky (BV)
field-antifield formalism of quantization of gauge theories with the non-local
regularization (NLR) method. The objective of this work is to make an analysis
of the behaviour of this NLR formalism, connected to the BV framework, using
two different regulators: a simple second order differential regulator and a
Fujikawa-like regulator. This analysis has been made in the light of the well
known fact that different regulators can generate different expressions for
anomalies that are related by a local couterterm, or that are equivalent after
a reparametrization. This has been done by computing precisely the anomaly of
the chiral Schwinger model.

</DOC>
<DOC>
<DOCNO> 174459 </DOCNO>
New results of 116Cd double beta decay study with 116CdWO4 scintillators


  A new phase of 116Cd double beta decay experiment is in progress in the
Solotvina Underground Laboratory. Four enriched 116CdWO4 scintillators with
total mass 339 g are used in a set up, whose active shield is made of 15
natural CdWO4 crystals (20.6 kg). The background rate in the energy interval
2.5-3.2 MeV is 0.03 counts/y*kg*keV. The half-life for 2-neutrino 2-beta decay
of 116Cd is measured as T{1/2}(2-neutrino) =
[2.6+-0.1(stat)-0.4+0.7}(syst)]*10**19 y. The T{1/2} limits for neutrinoless
2-beta decay of 116Cd are set as T{1/2} >= 0.7(2.5)*10**23 y at 90%(68%) C.L.
for transition to ground state of 116Sn, while for decays to the first 2+ and
second 0+ excited levels of 116Sn as T{1/2}>=1.3(4.8)*10**22 y and
>=0.7(2.4)*10**22 y with 90%(68%) C.L., respectively. For 0-neutrino 2-beta
decay with emission of one or two Majorons, the limits are T{1/2}(0-neutrino
M1) >=3.7(5.8)*10**21 y and T{1/2}(0-neutrino M2)>=5.9(9.4)*10**20 y at
90%(68%) C.L. Restrictions on the value of the neutrino mass, right-handed
admixtures in the weak interaction, and the neutrino-Majoron coupling constant
are derived as: m(neutrino)<=2.6(1.4) eV, eta <=3.9*10**-8, lambda
<=3.4*10**-6, and g{M}<= 12(9.5)*10**-5 at 90%(68%) C.L., respectively.

</DOC>
<DOC>
<DOCNO> 71289 </DOCNO>
Light flavor sea-quark asymmetry for the spin-dependent distribution


  The theoretical predictions of the chiral quark soliton model for the
unpolarized and longitudinally polarized structure functions of the nucleon are
compared with recent high energy data. The theory is shown to explain all the
qualitatively noticeable features of the existing experiments, including the
light flavor sea-quark asymmetry for the unpolarized distribution functions
established by the NMC measurement as well as very small quark spin fraction of
the nucleon indicated by the EMC measurement. Another unique feature of the
model is that it predicts sizably large isospin asymmetry also for the
spin-dependent sea-quark distribution functions.

</DOC>
<DOC>
<DOCNO> 85148 </DOCNO>
Quantum Cosmology in Bergmann-Wagoner Scalar-tensor Gravitational Theory


  The Wheeler-DeWitt equation is solved for the Bergmann-Wagoner scalar-tensor
gravitational theory in the case of Friedmann-Robertson- Walker cosmological
model. We present solutions for several cosmological functions: i)
\lambda(\phi)=0, ii) \lambda(\phi)=3\Lambda_0\phi and iii) a more complex
\lambda(\phi), that depends on the choice of the coupling function, considering
closed, flat and hyperbolic Friedmann universes (k=1, 0, -1). In the first two
cases we show particular quantum wormhole solutions. Also, classical solutions
are considered for some scalar-tensor theories, and we study the third
quantization of some minisuperspace models.

</DOC>
<DOC>
<DOCNO> 119288 </DOCNO>
Dynamic Work Distribution for PM Algorithm


  Although poor for small dynamic scales, the Particle-Mesh (PM) model allows
in astrophysics good insight for large dynamic scales at low computational
cost. Furthermore, it is possible to employ a very high number of particles to
get high mass resolution. These properties could be exploited by suitable
parallelization of the algorithm. In PM there are two types of data: the
particle data, i.e. position and velocity, which are stored in one-dimensional
arrays of N elements, and the grid data, i.e. density and force, which are
stored in three-dimensional arrays $M\times M\times M$ in size. Since
individual particles can change cell under the action of gravitational force,
parallelization is a real challenge on parallel machine and must account for
the machine architecture. We have implemented a dynamic work distribution
through agenda parallelism. By subdividing the work in small tasks, the
implementation is well balanced, scalable and efficient also for clustered
particle distributions. In this contribution we describe this efficient, load
balanced, parallel implementation of PM algorithm on Cray T3E at CINECA and
show its performances on cosmological simulation results.

</DOC>
<DOC>
<DOCNO> 122673 </DOCNO>
On the history of the interplay between HD 56925 and NGC 2359


  NGC 2359 is an optical nebula excited by the powerful wind and the radiation
of the Wolf-Rayet star HD 56925. We have investigated the interaction between
this massive star and the surrounding neutral gas by analyzing the large-scale
21cm-HI emission and by mapping the nebula in the J = 1-0 and the J = 2-1 lines
of CO. We found a conspicuous (70 x 37 pc) HI shell, expanding at 12 km/s,
likely produced during the main-sequence phase of the star. The molecular gas
towards NGC 2359 shows three velocity components. Two of these components, A1
and A2, have narrow linewidths (1-2 km/s) and radial velocities of 35-38 and
64-68 km/s, respectively. The third component is detected at radial velocities
between 50 and 58 km/s and has a broader profile (up to 5.5 km/s). Furthermore,
this component is morphologicaly related with the nebula and has a velocity
gradient of a few km/s. We have also estimated the physical parameters of the
molecular gas by means of a LVG modelling of the CO emission. The gas projected
onto the southern HII region of the nebula has low CO column density and is
rather hot, probably up to 80 K. Several profiles of the 13CO J = 1-0 line near
the peak of the emission, together with a weak emission bridge between the
broad and one of the narrow components (component A2), suggest the presence of
a shock front acting in the southern part of the nebula. This shock was likely
produced in a previous RSG/LBV phase of HD 56925.

</DOC>
<DOC>
<DOCNO> 10865 </DOCNO>
Many-particle entanglement with Bose--Einstein condensates


  We propose a method to produce entangled states of several particles starting
from a Bose-Einstein condensate. In the proposal, a single fast $\pi/2$ pulse
is applied to the atoms and due to the collisional interaction, the subsequent
free time evolution creates an entangled state involving all atoms in the
condensate. The created entangled state is a spin-squeezed state which could be
used to improve the sensitivity of atomic clocks.

</DOC>
<DOC>
<DOCNO> 101752 </DOCNO>
Discrete Symmetries and Clifford Algebras


  An algebraic description of basic discrete symmetries (space reversal P, time
reversal T and their combination PT) is studied. Discrete subgroups of
orthogonal groups of multidimensional spaces over the fields of real and
complex numbers are considered in terms of fundamental automorphisms of
Clifford algebras. In accordance with a division ring structure, a complete
classification of automorphisms groups is established for the Clifford algebras
over the field of real numbers. The correspondence between eight double
coverings (Dabrowski groups) of the orthogonal group and eight types of the
real Clifford algebras is defined with the use of isomorphisms between the
automorphism groups and finite groups. Over the field of complex numbers there
is a correspondence between two nonisomorphic double coverings of the complex
orthogonal group and two types of complex Clifford algebras. It is shown that
these correspondences associate with a well-known Atiyah-Bott-Shapiro
periodicity. Generalized Brauer-Wall groups are introduced on the extended sets
of the Clifford algebras. The structure of the inequality between the two
Clifford-Lipschitz groups with mutually opposite signatures is elucidated. The
physically important case of the two different double coverings of the Lorentz
groups is considered in details.

</DOC>
<DOC>
<DOCNO> 11809 </DOCNO>
Coarse Graining of Nonbonded Inter-particle Potentials Using Automatic


  We implemented a coarse-graining procedure to construct mesoscopic models of
complex molecules. The final aim is to obtain better results on properties
depending on slow modes of the molecules. Therefore the number of particles
considered in molecular dynamics simulations is reduced while conserving as
many properties of the original substance as possible. We address the problem
of finding nonbonded interaction parameters which reproduce structural
properties from experiment or atomistic simulations. The approach consists of
optimizing automatically nonbonded parameters using the simplex algorithm to
fit structural properties like the radial distribution function as target
functions. Moreover, any mix of structural and thermodynamic properties can be
included in the target function. Different spherically symmetric inter-particle
potentials are discussed. Besides demonstrating the method for Lennard--Jones
liquids, it is applied to several more complex molecular liquids such as
diphenyl carbonate, tetrahydrofurane, and monomers of poly(isoprene).

</DOC>
<DOC>
<DOCNO> 150497 </DOCNO>
Second Quantized F-P Ghost States


  Negative norm Hilbert space state vectors can be BRST invariant, we show in a
simplified Y-M model, which has gluons and ghost fields only, that such states
can be created by starting with gluons only.

</DOC>
<DOC>
<DOCNO> 101726 </DOCNO>
Sheaves and Local Subgroupoids


  This is an introduction to the notion of local subgroupoid introduced by the
author and R. Brown. It can also serve as an introduction to an application of
sheaf theory, and so could be useful to beginners in that theory. The main
results are the construction of the holonomy groupoid and the notion of s-sheaf
for certain local subgroupoids s.

</DOC>
<DOC>
<DOCNO> 119861 </DOCNO>
Kinematics of elliptical galaxies with a diffuse dust component - II.


  Observations have demonstrated the presence of substantial amounts of
interstellar dust in elliptical galaxies, most of which is believed to be
distributed diffusely over the galaxy. Absorption by dust grains has a major
impact on the transfer of stellar radiation, and affects the projection of each
physical (and kinematic) quantity. In a previous paper, we have investigated
the effects of a diffusely distributed dust component on the observed
kinematics of spherical galaxies. In this paper we investigate the effect of
not taking dust into account in dynamical modelling procedures. We use a set of
semi-analytical dusty galaxy models to create synthetic LOSVD data sets, which
we then model as if no dust were present.
  We find some considerable differences between the best-fitting models and the
input models, and we find that these differences are dependent on the orbital
structure of the input galaxy. For radial and isotropic models on the one hand,
we find that the dynamical mass of the models decreases nearly linearly with
optical depth, with an amount of 5 per cent per optical depth unit, whereas
their orbital structure is hardly affected. For tangential models on the other
hand, the dynamical mass decrease is smaller, but their orbital structure is
affected: their distribution functions appears less tangentially anisotropic.
For all models the mass-to-light ratio will be underestimated, by a factor of
around 20 per cent per optical depth unit.
  We discuss these results in the light of the limited effects of dust
extinction on the LOSVDs, as obtained in paper I, and conclude that the
determination of the dynamical mass and the kinematic structure of galaxies...
(for full abstract, see paper)

</DOC>
<DOC>
<DOCNO> 122635 </DOCNO>
Orbital elements of barium stars formed through a wind accretion


  Taking the total angular momentum conservation in place of the tangential
momentum conservation, and considering the square and higher power terms of
orbital eccentricity e, the changes of orbital elements of binaries are
calculated for wind accretion scenario. These new equations are used to
quantitatively explain the observed (e,logP) properties of normal G, K giants
and barium stars. Our results reflect the evolution from G, K giant binaries to
barium binaries, moreover, the barium stars with longer orbital periods P>1600
days may be formed by accreting part of the ejecta from the intrinsic AGB stars
through wind accretion scenario.

</DOC>
<DOC>
<DOCNO> 12396 </DOCNO>
Critical currents in Josephson junctions with macroscopic defects


  The critical currents in Josephson junctions of conventional superconductors
with macroscopic defects are calculated for different defect critical current
densities as a function of the magnetic field. We also study the evolution of
the different modes with the defect position, at zero external field. We study
the stability of the solutions and derive simple arguments, that could help the
defect characterization. In most cases a reentrant behavior is seen, where both
a maximum and a minimum current exist.

</DOC>
<DOC>
<DOCNO> 10539 </DOCNO>
Orientational pinning of quantum Hall striped phase


  In ultra-clean 2D electron systems on (001) GaAs/AlGaAs upon filling high
Landau levels, it was recently observed a new class of collective states, which
can be related to the spontaneous formation of a charge density wave (``striped
phase''). We address to the following unsolved problem: what is the reason for
stripe pinning along the crystallographic direction [110]? It is shown that in
a single heterojunction (001) III-V the effective mass of 2D electrons is
anisotropic. This natural anisotropy is due to the reduced (C_{2v}) symmetry of
the heterojunction and, even being weak (0.1 percent), can govern the stripe
direction. A magnetic field parallel to the interface induces ``magnetic''
anisotropy of the effective mass. The competition of these two types of
anisotropy provides quantitative description of the experiment.

</DOC>
<DOC>
<DOCNO> 68069 </DOCNO>
Measuring B -> rho pi decays and the unitarity angle alpha


  The decay mode B -> rho pi is currently studied as a channel allowing, in
principle, to measure without ambiguities the angle alpha of the unitarity
triangle. It is also investigated by the CLEO Collaboration where a branching
ratio larger than expected for the decay mode B+/- -> rho0 pi+/- has been
found. We investigate the role that the B* and B(0+) resonances play in these
analyses.

</DOC>
<DOC>
<DOCNO> 100543 </DOCNO>
On associative algebras with unity and Lie index 1


  We present a new method of analysis of associative algebras. This method
bears a certain resemblance to the famous analysis of commutative
$C^*$-algebras in which an important role is played by multiplicative
functionals over the algebra. These functionals can be considered as "rank 1"
in the framework of our method. In our approach a special position is taken by
generic (maximal rank) functionals, which reveal a wealth of information on the
structure of non-commutative algebras. We apply this method to derive
interesting properties of index of Lie algebras and to analyze
finite-dimensional associative algebras with unity and Lie index 1.

</DOC>
<DOC>
<DOCNO> 7764 </DOCNO>
Analytical Estimate of the Critical Velocity for Vortex Pair Creation in


  We use a modified Thomas-Fermi approximation to estimate analytically the
critical velocity for the formation of vortices in harmonically trapped BEC. We
compare this analytical estimate to numerical calculations and to recent
experiments on trapped alkali condensates.

</DOC>
<DOC>
<DOCNO> 72170 </DOCNO>
Neutrinoless Double Beta Decay in the Dualized Standard Model


  The Dualized Standard Model offers a {\it raison d'\^etre} for 3 fermion
generations and an explanation for their distinctive mass and mixing patterns,
reproducing to a reasonable accuracy the empirical mixing matrix and mass
spectrum for both quarks and leptons in terms of just a few parameters. With
its parameters thus fixed, the result is a highly predictive framework. In
particular, it is shown that it gives explicit parameter-free predictions for
neutrinoless double beta decays. For $^{76}Ge$, it predicts a half-life of
$10^{28}-10^{30}$ years, which satisfies the present experimental lower bound
of $1.8 \times 10^{25}$ years.

</DOC>
<DOC>
<DOCNO> 39750 </DOCNO>
Magnetic monopoles


  The main aim of this lecture is to give an update on the lectures on Magnetic
Monopoles (MMs) of the 1995 Trieste School. The update concerns theoretical
developments, searches for GUT monopoles in the penetrating cosmic radiation at
ever lower fluxes, study of the energy losses of MMs in the Earth and in
detectors,searches for low mass monopoles, and finally mention byproducts of MM
searches.

</DOC>
<DOC>
<DOCNO> 178509 </DOCNO>
A meson-exchange model of the associated photoproduction of vector


  We discuss the photoproduction of omega- and rho0-mesons off protons in the
particular channel where the target proton is excited to a Roper resonance
N*(1440). We propose a simple meson-exchange model for these processes in order
to evaluate their cross sections near threshold and at low momentum transfers.
It is suggested in particular that the differential cross section for the
associated photoproduction of a rho0-meson and a Roper resonance in these
kinematic conditions could provide direct information on the strength of the
scalar-isoscalar excitation of the N*(1440) and hence on the magnitude of an
effective sigma N N*(1440) coupling. The latter quantity is poorly known and of
much interest for the nuclear many-body problem.

</DOC>
<DOC>
<DOCNO> 178442 </DOCNO>
S=I=0 Pion Pairs in the A(pi,pi pi)X Reaction


  Recent experimental results show a large enhancement of the 2 pion emission
on the scalar isoscalar channel, which had been predicted by some theoretical
estimates. We present here a detailed calculation of the A(pi, 2pi)X process
incorporating a microscopic model for the elementary reaction in vacuum,
pion-pion final state interaction in the nuclear medium, and other nuclear
medium effects.

</DOC>
<DOC>
<DOCNO> 170547 </DOCNO>
Classical Versus Quantum Ontology


  This is an essay review of the book by D. Home: ``Conceptual Foundations of
Quantum Physics: An Overview from Modern Perspectives" (New York: Plenum Press,
1997), xvii+386 pp., ISBN 0-306-45660-5.

</DOC>
<DOC>
<DOCNO> 122484 </DOCNO>
The First Complete and Fully Sampled HI Survey of the Tidal Arms of the


  The LMC, SMC, and the Milky Way are a spectacular set of interacting
galaxies. The prominent tidal arms which protrude from the Magellanic Clouds
extend for tens of kiloparsecs and cover a large part of the southern sky.
These arms, and the Magellanic Clouds themselves, are therefore a highly
suitable subject for the detailed investigation of an interacting galaxy
system. We present the first results of the Parkes narrow-band HI survey of the
tidal arms of the Magellanic System. It is the first fully sampled, spatially
complete survey of this system. The data provide information on the column
density distribution and the variation of the shape of the line profiles over
the extent of the tidal features. We present a cloud catalogue of the tidal
features of the Magellanic System and discuss the distribution relative to the
observational parameters longitude, latitude and radial velocity (v_LSR and
v_GSR). We find a new stream-like feature that is most likely related to the
Leading Arm. Detailed investigation reveals a number of clouds showing a
cometary appearance in the position-velocity representation (so-called
head-tail structures). These head-tail structures are interpreted as clouds
that are currently interacting with an ambient medium.

</DOC>
<DOC>
<DOCNO> 151625 </DOCNO>
Constraints on brane and bulk ideal fluid in Randall-Sundrum cosmologies


  We investigate constraints for including bulk and brane matter in the
Randall- Sundrum model. In static configurations with two zero thickness
branes, we find that no realistic brane matter is possible. We also consider
the possibility that the radion has stabilized by dissipating its energy into
the bulk in the form of some unspecified matter, and find the Randall-Sundrum
cosmological solutions in the presence of bulk ideal fluid. We discover that
the metric is necessarily in a static configuration. We also discover that
there is only one allowed equation of state for the bulk fluid, $p=\rho $,
corresponding to the stiff ideal fluid. We find the corresponding brane
cosmologies and compare them with the Friedmann-Robertson-Walker model.

</DOC>
<DOC>
<DOCNO> 116641 </DOCNO>
Dark matter and the origin of mass: a simplified semiclassical approach


  The pervasive presence in space of a flux of high-speed, electrically
uncharged dark matter particles is examined here for potential consequences.
Dark matter interactions with ordinary matter are considered, and a model of
the dark matter flux is developed. In this model, the property of matter that
we designate as mass is a measure of the interaction cross section of ordinary
matter with the flux of dark matter. From this model emerge effects similar to
certain quantum phenomena, and also a flux-mediated attractive inverse-square
force between particles of ordinary matter. The occurrence of effects
resembling both quantum phenomena and effects resembling gravitational
phenomena in this model may enable a straightforward examination of convergence
of gravitational physics and quantum mechanics.

</DOC>
<DOC>
<DOCNO> 101673 </DOCNO>
Second class particles as microscopic characteristics in totally


  We study aspects of the hydrodynamics of one-dimensional totally asymmetric
K-exclusion, building on the hydrodynamic limit of Seppalainen (1999). We prove
that the weak solution chosen by the particle system is the unique one with
maximal current past any fixed location. A uniqueness result is needed because
we can prove neither differentiability nor strict concavity of the flux
function, so we cannot use the Lax-Oleinik formula or jump conditions to define
entropy solutions. Next we prove laws of large numbers for a second class
particle in K-exclusion. The macroscopic trajectories of second class particles
are characteristics and shocks of the conservation law for the particle
density. In particular, we extend to K-exclusion Ferrari's result that the
second class particle follows a macroscopic shock in the Riemann solution. The
technical novelty of the proofs is a variational representation for the
position of a second class particle, in the context of the variational coupling
method.

</DOC>
<DOC>
<DOCNO> 9239 </DOCNO>
Resonant Spin-Dependent Tunneling in Spin-Valve Junctions in the


  The tunnel magnetoresistance (TMR) of F/O/F magnetic junctions, (F's are
ferromagnetic layers and O is an oxide spacer) in the presence of magnetic
impurities within the barrier, is investigated. We assume that magnetic
couplings exist both between the spin of impurity and the bulk magnetization of
the neighboring magnetic electrode, and between the spin of impurity and the
spin of tunneling electron. Consequently, the resonance levels of the system
formed by a tunneling electron and a paramagnetic impurity with spin S=1, are a
sextet. As a result the resonant tunneling depends on the direction of the
tunneling electron spin. At low temperatures and zero bias voltage the TMR of
the considered system may be larger than TMR of the same structure without
paramagnetic impurities. It is calculated that an increase in temperature leads
to a decrease in the TMR amplitude due to excitation of spin-flip processes
resulting in mixing of spin up and down channels. It is also shown that
asymmetry in the location of the impurities within the barrier can lead to
asymmetry in $I(V)$ characteristics of impurity assisted current and two
mechanisms responsible for the origin of this effect are established. The first
one is due to the excitation of spin-flip processes at low voltages and the
second one arises from the shift of resonant levels inside the insulator layer
under high applied voltages.

</DOC>
<DOC>
<DOCNO> 11031 </DOCNO>
Oscillatory Curie temperature of two-dimensional ferromagnets


  The effective exchange interactions of magnetic overlayers Fe/Cu(001) and
Co/Cu(001) covered by a Cu-cap layer of varying thickness were calculated in
real space from first principles. The effective two-dimensional Heisenberg
Hamiltonian was constructed and used to estimate magnon dispersion laws,
spin-wave stiffness constants, and overlayer Curie temperatures within the
mean-field and random-phase approximations. Overlayer Curie temperature
oscillates as a function of the cap-layer thickness in a qualitative agreement
with a recent experiment.

</DOC>
<DOC>
<DOCNO> 152505 </DOCNO>
A Note About Localized Photons on the Brane


  A first order formulation for the Maxwell field in five dimensions is
dimensionally reduced using the Randall-Sundrum mechanism. We will see that
massive photons can not be localized on the brane.

</DOC>
<DOC>
<DOCNO> 102916 </DOCNO>
{Operator quantization of constrained WZNW theories and coset


  Using two WZNW theories for Lie algebras $g$ and $h, h\subset g,$ we
construct the associative quotient algebra which includes a class of $g/h$
coset primary fields and currents.

</DOC>
<DOC>
<DOCNO> 40039 </DOCNO>
Measurement of exclusive omega electroproduction at HERA


  The exclusive electroproduction of omega mesons, ep -> e omega p, has been
studied in the kinematic range 3<Q^2<20 GeV^2, 40<W<120 GeV and |t|<0.6 GeV^2
with the ZEUS detector at HERA using an integrated luminosity of 37.7 pb^{-1}.
The omega mesons were identified via the decay omega -> pi^+pi^-pi^0. The
exclusive (ep -> e omega p) cross section in the above kinematic region is
0.108 +- 0.014(stat.) +- 0.026(syst.) nb. The reaction ep -> e phi p, phi ->
pi^+pi^-pi^0, has also been measured. The cross sections, as well as the
cross-section ratios omega/rho and omega/phi, are presented as a function of W
and Q^2. Thus, for the first time, the properties of omega electroproduction
can be compared to those of rho^0, phi and J/psi electroproduction at high W.

</DOC>
<DOC>
<DOCNO> 119275 </DOCNO>
Dense gas in nearby galaxies XIII. CO submillimeter line emission from


  12CO 1-0,2-1,4-3,7-6, and 13CO 1-0, 2-1, and 3-2 line was mapped with angular
resolutions of 13" - 22" toward the nuclear region of starburst galaxy M82. The
difference of lobe spacings in submillimeter (~15") and millimeter (~26") lines
indicates the presence of a `low' and a `high' CO excitation component. An LVG
excitation analysis of the submillimeter lines leads to inconsistencies, since
area and volume filling factors are almost the same, resulting in cloud sizes
along the lines-of-sight that match the entire size of the M82 starburst
region. Nevertheless, LVG column densities agree with estimates derived from
the dust emission in the far infrared and at submillimeter wavelengths.
Accounting for high UV fluxes and variations in kinetic temperature and
assuming that the observed emission arises from photon dominated regions (PDRs)
resolves the problems related to an LVG treatment of the radiative transfer.
12CO/13CO line intensity ratios > 10 indicate that the bulk of the CO emission
arises in UV-illuminated diffuse cloud fragments of small column density and
sub-parsec cloud sizes with area filling factors >> 1. Thus CO arises from
quite a different gas component than the classical high density tracers. The
dominance of such a diffuse molecular interclump medium also explains observed
high [CI}/CO line intensity ratios. PDR models do not allow a determination of
the relative abundances of 12CO to 13CO. Ignoring magnetic fields, the CO gas
appears to be close to the density limit for tidal disruption. A warm diffuse
ISM not only dominates the CO emission in the starburst region of M82 but is
also ubiquitous in the central region of our Galaxy, where tidal stress,
cloud-cloud collisions, shocks, high gas pressure, and high stellar densities
may all contribute to the formation of a highly fragmented molecular debris.

</DOC>
<DOC>
<DOCNO> 8398 </DOCNO>
Effective potential approach to quantum dissipation in condensed matter


  The effects of dissipation on the thermodynamic properties of nonlinear
quantum systems are approached by the path-integral method in order to
construct approximate classical-like formulas for evaluating thermal averages
of thermodynamic quantities. Explicit calculations are presented for
one-particle and many-body systems. The effects of the dissipation mechanism on
the phase diagram of two-dimensional Josephson arrays is discussed.

</DOC>
<DOC>
<DOCNO> 8669 </DOCNO>
Controlling anomalous stresses in soft field-responsive systems


  We report a new phenomenon occurring in field-responsive suspensions:
shear-induced anomalous stresses. Competition between a rotating field and a
shear flow originates a multiplicity of anomalous stress behaviors in
suspensions of bounded dimers constituted by induced dipoles. The great variety
of stress regimes includes non-monotonous behaviors, multi-resonances, negative
viscosity effect and blockades. The reversibility of the transitions between
the different regimes and the self-similarity of the stresses make this
phenomenon controllable and therefore applicable to modify macroscopic
properties of soft condensed matter phases

</DOC>
<DOC>
<DOCNO> 116762 </DOCNO>
Temperature, Pressure & Solvent Dependence of Positronium Acceptor


  Positronium (Ps) reaction rates (k) with weak Acceptors (Ac) leading to the
formation of Ps-Ac Complexes show several intriguing features: non-monotonic
temperature dependence of k (departing from the usual Arrhenius paradigm),
considerable variablity of k with respect to different solvents, and anomalies
in response to external pressure at ambient temperature (large changes of k in
some media and hardly any in others). We explain all these phenomena, through
the introduction of the novel concept of a critical surface tension, which
unifies observations in diverse non-polar solvents at different temperatures
and pressures.

</DOC>
<DOC>
<DOCNO> 118098 </DOCNO>
Gravitational lens magnification by Abell 1689: Distortion of the


  Gravitational lensing magnifies the luminosity of galaxies behind the lens.
We use this effect to constrain the total mass in the cluster Abell 1689 by
comparing the lensed luminosities of background galaxies with the luminosity
function of an undistorted field. Since galaxies are assumed to be a random
sampling of luminosity space, this method is not limited by clustering noise.
We use photometric redshift information to estimate galaxy distance and
intrinsic luminosity. Knowing the redshift distribution of the background
population allows us to lift the mass/background degeneracy common to lensing
analysis. In this paper we use 9 filters observed over 12 hours with the Calar
Alto 3.5m telescope to determine the redshifts of 1000 galaxies in the field of
Abell 1689. Using a complete sample of 151 background galaxies we measure the
cluster mass profile. We find that the total projected mass interior to
0.25h^(-1)Mpc is (0.48 +/- 0.16) * 10^(15)h^(-1) solar masses, where our error
budget includes uncertainties from the photometric redshift determination, the
uncertainty in the off-set calibration and finite sampling. This result is in
good agreement with that found by number count and shear-based methods and
provides a new and independent method to determine cluster masses.

</DOC>
<DOC>
<DOCNO> 67913 </DOCNO>
Casimir scaling as a test of QCD vacuum


  Recent accurate measurements of static potentials between sources in various
representations of the gauge group SU(3) performed by G.Bali provide a crucial
test of the QCD vacuum models and different approaches to confinement. The
Casimir scaling of the potential observed for all measured distances implies
strong suppression of higher cumulant contributions. The consequences for the
instanton vacuum model and the spectrum of the QCD string are also discussed.

</DOC>
<DOC>
<DOCNO> 40347 </DOCNO>
Search for a Scalar Bottom Quark with Mass 3.5-4.5 GeV/$c^{2}$


  We report on a search for a supersymmetric $\tilde{B}$ meson with mass
between 3.5 and 4.5 GeV/$c^2$ using 4.52 ${\rm fb}^{-1}$ of integrated
luminosity produced at $\sqrt{s}=10.52$ GeV, just below the $e^+e^-\to
B\bar{B}$ threshold, and collected with the CLEO detector. We find no evidence
for a light scalar bottom quark.

</DOC>
<DOC>
<DOCNO> 85622 </DOCNO>
Large fluctuations of time and change of space-time signature


  We consider five-dimensional cylindric spacetime $V^5$ with foliation of
codimension ~1. The leaves of this foliation are four-dimensional
 "parallel" universes. The metric of five-dimensional spacetime and induced
metrics of four-dimensional universes are flat. The "large" fluctuations of the
5-metric are studied. These fluctuations depend only on the coordinate $x^0$,
and under these fluctuations the curvature of $V^5$ is not zero. The
contribution of the fluctuations in the Feynman path integral over
five-dimensional trajectories doesn't change the amplitude of the probability
of the real physical four-dimensional universe. Moreover the large fluctuations
of 5-metric $G_{AB}$ are large fluctuations for physical four-dimensional
universe $V^4$ and change signature of $V^4$. The change of the signature from
$<+--->$ to $<---->$ and inversely occurs in the all 3-dimensional space
simultaneously (in absolute time) and can take arbitrarily large period of
time.

</DOC>
<DOC>
<DOCNO> 83089 </DOCNO>
Safe cooperative robot dynamics on graphs


  This paper initiates the use of vector fields to design, optimize, and
implement reactive schedules for safe cooperative robot patterns on planar
graphs. We consider Automated Guided Vehicles (AGV's) operating upon a
predefined network of pathways. In contrast to the case of locally Euclidean
configuration spaces, regularization of collisions is no longer a local
procedure, and issues concerning the global topology of configuration spaces
must be addressed. The focus of the present inquiry is the achievement of safe,
efficient, cooperative patterns in the simplest nontrivial example (a pair of
robots on a Y-network) by means of a state-event heirarchical controller.

</DOC>
<DOC>
<DOCNO> 116627 </DOCNO>
Classical double ionization of atoms in strong fields


  Recent high resolution measurements of the momenta of two electrons emitted
from Argon atoms in a strong laser field show a strong preference for the
outgoing electrons to have similar momenta and to be ejected in the same
direction along the field. We discuss the final stages of this process in a
classical model in the spirit of Wanniers approach to double ionization after
electron impact. Starting from an intermediate state of high but negative
energy the field opens up a channel through which both electrons can escape.
Near the threshold for this process Coulomb repulsion favors an escape with the
electron momenta and positions symmetric with respect to the electric field
axis. Classical trajectory simulations within this symmetry subspace account
for most features of the observed momentum distribution.

</DOC>
<DOC>
<DOCNO> 121693 </DOCNO>
High Speed Phase-Resolved 2-d UBV Photometry of the Crab pulsar


  We report a phase-resolved photometric and morphological analysis of UBV data
of the Crab pulsar obtained with the 2-d TRIFFID high speed optical photometer
mounted on the Russian 6m telescope. By being able to accurately isolate the
pulsar from the nebular background at an unprecedented temporal resolution (1
\mu s), the various light curve components were accurately fluxed via
phase-resolved photometry. Within the $UBV$ range, our datasets are consistent
with the existing trends reported elsewhere in the literature. In terms of flux
and phase duration, both the peak Full Width Half Maxima and Half Width Half
Maxima decrease as a function of photon energy. This is similarly the case for
the flux associated with the bridge of emission. Power-law fits to the various
light curve components are as follows; \alpha = 0.07 \pm 0.19 (peak 1), \alpha
= -0.06 \pm 0.19 (peak 2) and \alpha = -0.44 \pm 0.19 (bridge) - the
uncertainty here being dominated by the integrated CCD photometry used to
independently reference the TRIFFID data. Temporally, the main peaks are
coincident to \le 10 \mu s although an accurate phase lag with respect to the
radio main peak is compromised by radio timing uncertainties. The plateau on
the Crab's main peak was definitively determined to be \leq 55 \mu s in extent
and may decrease as a function of photon energy. There is no evidence for
non-stochastic activity over the light curves or within various phase regions,
nor is there evidence of anything akin to the giant pulses noted in the radio.
Finally, there is no evidence to support the existence of a reported 60 second
modulation suggested to be as a consequence of free precession.

</DOC>
<DOC>
<DOCNO> 169593 </DOCNO>
Geometric Phase, Curvature, and Extrapotentials in Constrained Quantum


  We derive an effective Hamiltonian for a quantum system constrained to a
submanifold (the constraint manifold) of configuration space (the ambient
space) by an infinite restoring force. We pay special attention to how this
Hamiltonian depends on quantities which are external to the constraint
manifold, such as the external curvature of the constraint manifold, the
(Riemannian) curvature of the ambient space, and the constraining potential. In
particular, we find the remarkable fact that the twisting of the constraining
potential appears as a gauge potential in the constrained Hamiltonian. This
gauge potential is an example of geometric phase, closely related to that
originally discussed by Berry. The constrained Hamiltonian also contains an
effective potential depending on the external curvature of the constraint
manifold, the curvature of the ambient space, and the twisting of the
constraining potential. The general nature of our analysis allows applications
to a wide variety of problems, such as rigid molecules, the evolution of
molecular systems along reaction paths, and quantum strip waveguides.

</DOC>
<DOC>
<DOCNO> 67988 </DOCNO>
Neutrinos: Heralds of New Physics


  The central role of neutrinos in the determination of fundamental
interactions is reviewed. The recent SuperKamiokande discovery of neutrino mass
gives an {\it aper\c cu} of physics at short distances, and tests theories of
flavor. Quark-lepton symmetries, derived from grand unification and/or string
theories, can help determine the standard model parameters in the neutrino
sector.

</DOC>
<DOC>
<DOCNO> 99811 </DOCNO>
Birational properties of pencils of del Pezzo surfaces of degree 1 and 2


  We study the birational rigidity problem for smooth Mori fibrations on del
Pezzo surfaces of degree 1 and 2. For degree 1 we obtain a complete description
of rigid and non-rigid cases.

</DOC>
<DOC>
<DOCNO> 69150 </DOCNO>
Rho-omega mixing in asymmetric nuclear matter via QCD sum rule approach


  We evaluate the operator product expansion (OPE) for a mixed correlator of
the isovector and isoscalar vector currents in the background of the nucleon
density with intrinsic isospin asymmetry [i.e. excess of neutrons over protons]
and match it with its imaginary part, given by resonances and continuum, via
the dispersion relation. The leading density-dependent contribution to
$\rho-\omega$ mixing is due the scattering term, which turns out to be larger
than any density dependent piece in the OPE. We estimate that the asymmetric
density of $n_n-n_p \sim 2.5 \times 10^{-2} ~{\rm fm^3}$ induces the amplitude
of $\rho-\omega$ mixing, equal in magnitude to the mixing amplitude in vacuum,
with the constructive interference for positive and destructive for negative
values of $n_n-n_p$. We revisit sum rules for vector meson masses at finite
nucleon density to point out the numerical importance of the screening term in
the isoscalar channel, which turns out to be one order of magnitude larger than
any density-dependent condensates over the Borel window. This changes the
conclusions about the density dependence of $m_\omega$, indicating $\sim 40$
MeV increase at nuclear saturation density.

</DOC>
<DOC>
<DOCNO> 71754 </DOCNO>
Physics From Extra Dimensions


  A brief review of the recent developments in the physics from extra
dimensions is given with a focus on the effects of Kaluza-Klein excitations in
the Standard Model sector. It is shown that the current accurate data on the
Fermi constant and on other electro-weak parameters puts a lower bound on the
scale of extra dimensions of $\sim$ 3 TeV, and thus the observation of such
dimensions lies beyond the reach of accelerators in the near future. The
correction to the anomalous magnetic moment of the muon from extra dimensions
is discussed and one finds that with the current limit on the scale of extra
dimensions from the Fermi constant, the correction to $g_{\mu}-2$ does not
compete with the potentially large contributions from the supersymmetric
electro-weak correction. The possibility of generating Kaluza-Klein excitations
associated with large radius compactifications at the LHC is discussed. It is
shown that if such excitations are indeed produced their resonance structure
will encode information on the number of compactified dimensions as well as on
the nature of the specific orbifold compactification. A brief discussion of
difficulties such as rapid proton decay that one encounters in theories with
large radius compactifications is given.

</DOC>
<DOC>
<DOCNO> 121508 </DOCNO>
Canonical Timing and Spectral Behavior of LMC X-3 in the Low/Hard State


  We present results from three observations with the Rossi X-ray Timing
Explorer (RXTE) of LMC X-3, obtained while the source was in an extended
'low/hard' state. The data reveal a hard X-ray spectrum which is well fit by a
pure power law with photon index Gamma=1.69+/-0.02, with a source luminosity at
50 kpc of 5-16x10^{36}erg/s (2--10 keV). Strong broad-band (0.01-100 Hz) time
variability is also observed, with fractional rms amplitude 40+/-4%, plus a
quasi-periodic oscillation (QPO) peak at 0.46+/-0.02 Hz with rms amplitude
\~14%. This is the first reported observation in which the full canonical
low/hard state behavior (pure hard power law spectrum combined with strong
broad-band noise and QPO) for LMC X-3 is seen. We reanalyze several archival
RXTE observations of LMC X-3 and derive consistent spectral and timing
parameters, and determine the overall luminosity variation between high/soft
and low/hard states. The timing and spectral properties of LMC X-3 during the
recurrent low/hard states are quantitatively similar to that typically seen in
the Galactic black hole candidates.

</DOC>
<DOC>
<DOCNO> 13818 </DOCNO>
Enforced Electrical Neutrality of the Color-Flavor Locked Phase


  We demonstrate that quark matter in the color-flavor locked phase of QCD is
rigorously electrically neutral, despite the unequal quark masses, and even in
the presence of an electron chemical potential. As long as the strange quark
mass and the electron chemical potential do not preclude the color-flavor
locked phase, quark matter is automatically neutral. No electrons are required
and none are admitted.

</DOC>
<DOC>
<DOCNO> 68305 </DOCNO>
Transversity Distribution and Polarized Fragmentation Function from


  A method is discussed to determine the hitherto unknown u-quark transversity
distribution from a planned HERMES measurement of a single-spin asymmetry in
semi-inclusive pion electroproduction off a transversely polarized target.
Assuming u-quark dominance, the measurement yields the shapes of the
transversity distribution and of the ratio of a polarized and the unpolarized
u-quark fragmentation functions. The unknown relative normalization can be
obtained by identifying the transversity distribution with the well-known
helicity distribution at large x. The systematic uncertainty of the method is
dominated by the assumption of u-quark dominance.

</DOC>
<DOC>
<DOCNO> 121715 </DOCNO>
Forces on Dust Grains Exposed to Anisotropic Interstellar Radiation


  Grains exposed to anisotropic radiation fields are subjected to forces due to
the asymmetric photon-stimulated ejection of particles. These forces act in
addition to the ``radiation pressure'' due to absorption and scattering. Here
we model the forces due to photoelectron emission and the photodesorption of
adatoms. The ``photoelectric'' force depends on the ambient conditions relevant
to grain charging. We find that it is comparable to the radiation pressure when
the grain potential is relatively low and the radiation spectrum is relatively
hard. The calculation of the ``photodesorption'' force is highly uncertain,
since the surface physics and chemsitry of grain materials are poorly
understood at present. For our simple yet plausible model, the photodesorption
force dominates the radiation pressure for grains with size >~0.1 micron
exposed to starlight from OB stars. We find that the anisotropy of the
interstellar radiation field is ~10% in the visible and ultraviolet. We
estimate size-dependent drift speeds for grains in the cold and warm neutral
media and find that micron-sized grains could potentially be moved across a
diffuse cloud during its lifetime.

</DOC>
<DOC>
<DOCNO> 39740 </DOCNO>
Charm Results on CP Violation and Mixing


  The most recent results on CP violation and mixing in the charm system are
reviewed as a guide to the future. While no surprising results are reported so
far, charm provides a unique window to physics beyond the Standard Model. The
results reported here come from four sources: ALEPH at LEP, E791 and FOCUS/E831
at Fermilab, and CLEO II.V at CESR. Results beyond these sources may be
expected as a byproduct of B-motivated experiments.

</DOC>
<DOC>
<DOCNO> 7642 </DOCNO>
Tight-binding modelling of the electronic band structure of layered


  A detailed tight-binding analysis of the electron band structure of the CuO_2
plane of layered cuprates is performed within a sigma-band Hamiltonian
including four orbitals - Cu3d_x^2-y^2, Cu4s, O2p_x, and O2p_y. Both the
experimental and theoretical hints in favor of Fermi level located in a Cu or O
band, respectively, are considered. For these two alternatives analytical
expressions are obtained for the LCAO electron wave functions suitable for the
treatment of electron superexchange. Simple formulae for the Fermi surface and
electron dispersions are derived by applying the Loewdin down-fold procedure to
set up the effective copper and oxygen Hamiltonians. They are used to fit the
experimental ARUPS Fermi surface of Pb_0.42Bi_1.73Sr_1.94Ca_1.3Cu_1.92O_8+x and
both the ARPES and LDA Fermi surface of Nd_2-xCe_xCuO_4-delta. The value of
presenting the hopping amplitudes as surface integrals of ab initio atomic wave
functions is demonstrated as well. The same approach is applied to the RuO_2
plane of the ruthenate Sr_2RuO_4. The LCAO Hamiltonians including the three
in-plane pi-orbitals Ru4d_xy, O_a 2p_y, O_b 2p_x and the four transversal
pi-orbitals Ru4d_zx, Ru4d_yz, O_a 2p_z, O_b 2p_z, are separately considered. It
is shown that the equation for the constant energy curves and the Fermi
contours has the same canonical form as the one for the layered cuprates.

</DOC>
<DOC>
<DOCNO> 11889 </DOCNO>
Counting statistics of photons produced by electronic shot noise


  A theory is presented for the photodetection statistics of radiation produced
by current fluctuations in a phase-coherent conductor. Deviations are found
from the Poisson statistics that would result from a classical current. For
detection in a narrow frequency interval, the photocount distribution has the
negative-binomial form of black-body radiation if this frequency interval is
less than the mean current in the conductor. When electronic localization sets
in, a different type of super-Poissonian photon statistics results.

</DOC>
<DOC>
<DOCNO> 152265 </DOCNO>
Brane Resolution Through Transgression


  Modifications to the singularity structure of D3-branes that result from
turning on a flux for the R-R and NS-NS 3-forms (fractional D3-branes) provide
important gravity duals of four-dimensional N=1 super-Yang-Mills theories. We
construct generalisations of these modified p-brane solutions in a variety of
other cases, including heterotic 5-branes, dyonic strings, M2-branes,
D2-branes, D4-branes and type IIA and type IIB strings, by replacing the flat
transverse space with a Ricci-flat manifold M_n that admits covariantly
constant spinors, and turning on a flux built from a harmonic form in M_n, thus
deforming the original solution and introducing fractional branes. The
construction makes essential use of the Chern-Simons or ``transgression'' terms
in the Bianchi-identity or equation of motion of the field strength that
supports the original undeformed solution. If the harmonic form is L^2
normalisable, this can result in a deformation of the brane solution that is
free of singularities, thus providing viable gravity duals of field theories in
diverse dimensions that have less than maximal supersymmetry. We obtain
examples of non-singular heterotic 5-branes, dyonic strings, M2-branes, type
IIA strings, and D2-branes.

</DOC>
<DOC>
<DOCNO> 39930 </DOCNO>
Prospects for Colliders and Collider Physics to the 1 PeV Energy Scale


  A review is given of the prospects for future colliders and collider physics
at the energy frontier. A proof-of-plausibility scenario is presented for
maximizing our progress in elementary particle physics by extending the energy
reach of hadron and lepton colliders as quickly and economically as might be
technically and financially feasible. The scenario comprises 5 colliders beyond
the LHC -- one each of e+e- and hadron colliders and three muon colliders --
and is able to hold to the historical rate of progress in the log-energy reach
of hadron and lepton colliders, reaching the 1 PeV constituent mass scale by
the early 2040's. The technical and fiscal requirements for the feasibility of
the scenario are assessed and relevant long-term R&D projects are identified.
Considerations of both cost and logistics seem to strongly favor housing most
or all of the colliders in the scenario in a new world high energy physics
laboratory

</DOC>
<DOC>
<DOCNO> 151817 </DOCNO>
BPS D-branes after Tachyon Condensation


  We construct an effective action describing brane-antibrane system containing
N D-branes and N \bar{D}-branes. BPS equations for remaining D-branes after
tachyon condensation are derived and their properties are investigated. The
value of the D-brane tension and the number of brane bound states are
discussed.

</DOC>
<DOC>
<DOCNO> 11463 </DOCNO>
Self-Organized Criticality and Universality in a Nonconservative


  We make an extensive numerical study of a two dimensional nonconservative
model proposed by Olami-Feder-Christensen to describe earthquake behavior. By
analyzing the distribution of earthquake sizes using a multiscaling method, we
find evidence that the model is critical, with no characteristic length scale
other than the system size, in agreement with previous results. However, in
contrast to previous claims, we find convergence to universal behaviour as the
system size increases, over a range of values of the dissipation parameter,
$\alpha$. We also find that both ``free'' and ``open'' boundary conditions tend
to the same result.
 Our analysis indicates that, as $L$ increases, the behaviour slowly converges
toward a power law distribution of earthquake sizes
 $P(s) \sim s^{-\tau}$ with exponent $\tau \simeq 1.8$. The universal value of
$\tau$ we find numerically agrees quantitatively with the empirical value
($\tau=B+1$) associated with the Gutenberg-Richter law.

</DOC>
<DOC>
<DOCNO> 150972 </DOCNO>
Perturbative Chern-Simons Theory on Noncommutative R^3


  A U(N) Chern-Simons theory on noncommutative $\mathbb{R}^{3}$ is constructed
as a $\q$-deformed field theory. The model is characterized by two symmetries:
the BRST-symmetry and the topological linear vector supersymmetry. It is shown
that the theory is finite and $\q_{\m\n}$-independent at the one loop level and
that the calculations respect the restriction of the topological supersymmetry.
Thus the topological $\q$-deformed Chern-Simons theory is an example of a model
which is non-singular in the limit $\q \to 0$.

</DOC>
<DOC>
<DOCNO> 8899 </DOCNO>
Magnetoresistance in ordered and disordered double perovskite oxide,


  We have prepared crystallographically ordered and disorder specimens of the
double perovskite, Sr$_2$FeMoO$_6$ and investigated their magnetoresistance
behaviour. The extent of ordering between the Fe and Mo sites in the two
samples is determined by Rietveld analysis of powder x-ray diffraction patterns
and reconfirmed by M\"{o}ssbauer studies. While the ordered sample exhibits the
sharp low-field response, followed by moderate changes in the magnetoresistance
at higher fields, the disordered sample is characterised by the absence of the
spectacular low-field response. We argue that the low field response depends
crucially on the half-metallic ferromagnetism, while the high-field response
follows from the overall magnetic nature of the sample, even in absence of the
half-metallic state.

</DOC>
<DOC>
<DOCNO> 11345 </DOCNO>
Correlation functions in decorated lattice models


  Occupation probabilities for primary-secondary-primary cell strings and
correlation functions for primary sites of a decorated lattice model are
expressed through the well-studied partition function and correlation functions
of the Ising model. The results are analogous to those found in related lattice
models of hydrophobic interactions and are interpreted in similar terms.

</DOC>
<DOC>
<DOCNO> 178730 </DOCNO>
Many-body perturbation calculation of spherical nuclei with a separable


  We present calculations of ground state properties of spherical, doubly
closed-shell nuclei from $^{16}$O to $^{208}$Pb employing the techniques of
many-body perturbation theory using a separable density dependent monopole
interaction. The model gives results in Hartree-Fock order which are of similar
quality to other effective density-dependent interactions. In addition, second
and third order perturbation corrections to the binding energy are calculated
and are found to contribute small, but non-negligible corrections beyond the
mean-field result. The perturbation series converges quickly, suggesting that
this method may be used to calculate fully correlated wavefunctions with only
second or third order perturbation theory. We discuss the quality of the
results and suggest possible methods of improvement.

</DOC>
<DOC>
<DOCNO> 69558 </DOCNO>
Scalar Mediated FCNC at the First Muon Collider


  In the most general two-Higgs doublet model (generally referred to as Model
III), tree level flavor changing neutral couplings exist. It has been noted
that the most natural value for such a coupling is of the order of the
geometric mean of the Yukawa couplings of the two fermions. Bounds on those
couplings that involve the second and third generations, from $\tau,B,D$ and
$\mu$ physics, are very weak and are not sensitive to this "natural" value. In
this paper, it is pointed out that the process \mu\mu ---> \mu\tau, at a muon
collider tuned to the scalar resonance, will easily reach this sensitivity if
the scalar mass is below 140 GeV. Hundreds of events are expected for an
integrated luminosity of an inverse femtobarn, and there appears to be no
background. Failure to observe this process, if the scalar is below 140 GeV,
would effectively rule out Model III.

</DOC>
<DOC>
<DOCNO> 100351 </DOCNO>
p-Adic and Adelic Harmonic Oscillator with Time-Dependent Frequency


  The classical and quantum formalism for a p-adic and adelic harmonic
oscillator with time-dependent frequency is developed, and general formulae for
main theoretical quantities are obtained. In particular, the p-adic propagator
is calculated, and the existence of a simple vacuum state as well as adelic
quantum dynamics is shown. Space discreteness and p-adic quantum-mechanical
phase are noted.

</DOC>
<DOC>
<DOCNO> 12140 </DOCNO>
Resonant Tunnelling through InAs Quantum Dots in Tilted Magnetic Fields:


  We have determined the Land\'e factor g* in self-organized InAs quantum dots
using resonant-tunnelling experiments. With the magnetic field applied parallel
to the growth direction z we find g*_\parallel = 0.75 for the specific dot
investigated. When the magnetic field is tilted away by theta from the growth
axis, g* gradually increases up to a value g*_\perp = 0.92 when B \perp z. Its
angular dependence is found to follow the phenomenological behaviour g* (theta)
= \sqrt{(g*_\parallel cos(theta)^2 + (g*_\perp sin(theta)^2}.

</DOC>
<DOC>
<DOCNO> 67767 </DOCNO>
Dynamics of Glueball and qqbar production in the central region of pp


  We explain the phi and t dependences of mesons with JPC = 0-+, 0++,1++, 2-+
and 2++ produced in the central region of pp collisions. For the 0++ and 2++
sector this reveals a systematic behaviour in the data that appears to
distinguish between qqbar and non-qqbar or glueball candidates.

</DOC>
<DOC>
<DOCNO> 12271 </DOCNO>
Orbital-Degenerate Paramagnetic Metal Sr2MoO4: An Electronic Analogue to


  We present the first systematic study on polycrystalline Sr2MoO4 as an
electronic analogue to the spin-triplet superconductor Sr2RuO4. The Pauli
paramagnetic susceptibility and metallic behaviors of specific heat and
electrical resistivity have been observed. The density of states at the Fermi
level D(EF) deduced from the results is about three times smaller than that of
Sr2RuO4. Any indication of superconductivity intrinsic to Sr2MoO4 has not been
observed down to 25 mK, which may correspond to the smaller D(EF). We discuss
the origin of the difference in electronic states between Sr2MoO4 and Sr2RuO4.

</DOC>
<DOC>
<DOCNO> 85558 </DOCNO>
Evaluation of neutrinos mass based on ENU model


  Based on principles of the Expansive Nondecelerative Universe model that
enables to quantify and localize the gravitational energy density, and stemming
from the see-saw mechanism, the mass of electron, muon and tau neutrinos are
determined in an independent way.

</DOC>
<DOC>
<DOCNO> 117669 </DOCNO>
BVRcIc photometry of GRB 980703 and GRB 990123 host galaxies


  We present a photometry of GRB 980703 and GRB 990123 host galaxies which was
performed about 20 days and a half year after gamma-ray bursts occured,
respectively. The contributions of the optical transiets (OT) were negligible
in both cases. We derived broad band BVR_cI_c spectra of the host galaxies and
compared them to continuum spectra of different Hubble-type galaxies and
averaged spectra of starburst galaxies. For H_0=60 km s^{-1} Mpc^{-1} and three
Friedmann cosmological models with matter density and cosmological constant
parameters (Omega_m,Omega_Lambda) = (1,0),(0,0),(0,1) we estimated M_Brest and
star-forming rates (SFRs) using the fluxes in photometric bands for the host
galaxies. Within the range of cosmological parameters our estimates of the
absolute magnitudes are: M_Brest = -20.60 .. -21.73 for the GRB 980703 host
galaxy and M_Brest = -20.20 .. -21.82 for the GRB 990123 host galaxy. We
obtained estimates of K-correction values and absolute magnitudes of the host
galaxies using SEDs for star-forming galaxies.

</DOC>
<DOC>
<DOCNO> 67663 </DOCNO>
Large Yukawa coupling corrections to scalar quark pair production in


  We calculate the large Yukawa coupling corrections to the top and bottom
scalar quark pair production in $\ee$ annihilation within the Minimal
Supersymmetric Standard Model. We include the vertex corrections and the
corrections to the gauge boson propagator enhanced by large masses. We find the
total corrections are quite significant. In some regions of the parameter space
the corrections are larger than 10%.

</DOC>
<DOC>
<DOCNO> 118465 </DOCNO>
Cosmological Reionization


  In popular cosmological scenarios, some time beyond a redshift of 10, stars
within protogalaxies created the first heavy elements; these systems, together
perhaps with an early population of quasars, generated the ultraviolet
radiation and mechanical energy that reheated and reionized the cosmos. The
history of the Universe during and soon after these crucial formative stages is
recorded in the all-pervading intergalactic medium (IGM), which contains most
of the ordinary baryonic material left over from the big bang. Throughout the
epoch of structure formation, the IGM becomes clumpy and acquires peculiar
motions under the influence of gravity, and acts as a source for the gas that
gets accreted, cools, and forms stars within galaxies, and as a sink for the
metal enriched material, energy, and radiation which they eject.

</DOC>
<DOC>
<DOCNO> 99393 </DOCNO>
Redundant Picard-Fuchs system for Abelian integrals


  We derive an explicit system of Picard-Fuchs differential equations satisfied
by Abelian integrals of monomial forms and majorize its coefficients. A
peculiar feature of this construction is that the system admitting such
explicit majorants, appears only in dimension approximately two times greater
than the standard Picard-Fuchs system.
  The result is used to obtain a partial solution to the tangential Hilbert
16th problem. We establish upper bounds for the number of zeros of arbitrary
Abelian integrals on a positive distance from the critical locus. Under the
additional assumption that the critical values of the Hamiltonian are distant
from each other (after a proper normalization), we were able to majorize the
number of all (real and complex) zeros.
  In the second part of the paper an equivariant formulation of the above
problem is discussed and relationships between spread of critical values and
non-homogeneity of uni- and bivariate complex polynomials are studied.

</DOC>
<DOC>
<DOCNO> 151763 </DOCNO>
Low-Energy Effective Action in N=4 Super Yang-Mills Theories


  We review a recent progress in constructing low-energy effective action in
N=4 super Yang-Mills theories. Using harmonic superspace approach we consider
N=4 SYM in terms of unconstrained N=2 superfield and apply N=2 background field
method to finding effective action for N=4 SU(n) SYM broken down to
U(n)$^{n-1}$. General structure of leading low-energy corrections to effective
action is discussed.

</DOC>
<DOC>
<DOCNO> 150909 </DOCNO>
Strongly Coupled Gravity and Duality


  A strong coupling limit of theories whose low-energy effective field theory
is 5-dimensional N=8 supergravity is proposed in which the gravitational
coupling becomes large. It is argued that, if this limit exists, it should be a
6-dimensional theory with (4,0) supersymmetry compactified on a circle whose
radius gives the 5-dimensional Planck length. The sector corresponding to the
D=5 supergravity multiplet is a (4,0) D=6 superconformal field theory based on
the (4,0) multiplet with 27 self-dual 2-forms, 42 scalars and, instead of a
graviton, a fourth-rank tensor gauge field satisfying a self-duality
constraint. The superconformal field theory has 32 supersymmetries and 32
conformal supersymmetries and its dimensional reduction gives the maximal
supergravity in five dimensions. Electromagnetic duality generalises to a
gravitational triality.

</DOC>
<DOC>
<DOCNO> 13668 </DOCNO>
The Importance of being Odd


  In this letter I consider mainly a finite XXZ spin chain with periodic
boundary conditions and \bf{odd} \rm number of sites. This system is described
by the Hamiltonian $H_{xxz}=-\sum_{j=1}^{N}\{\sigma_j^{x}\sigma_{j+1}^{x}
  +\sigma_j^{y}\sigma_{j+1}^{y}
  +\Delta \sigma_j^z\sigma_{j+1}^z\}$. As it turned out, its ground state
energy is exactly proportional to the number of sites $E=-3N/2$ for a special
value of the asymmetry parameter $\Delta=-1/2$. The trigonometric polynomial
$q(u)$, zeroes of which being the parameters of the ground state Bethe
eigenvector is explicitly constructed. This polynomial of degree $n=(N-1)/2$
satisfy the Baxter T-Q equation. Using the second independent solution of this
equation corresponding to the same eigenvalue of the transfer matrix, it is
possible to find a derivative of the ground state energy w.r.t. the asymmetry
parameter. This derivative is closely connected with the correlation function
$<\sigma_j^z\sigma_{j+1}^z> =-1/2+3/2N^2$. In its turn this correlation
function is related to an average number of spin strings for the ground state
of the system under consideration: $<N_{string}> = {3/8}(N-1/N)$. I would like
to stress once more that all these simple formulas are \bf wrong \rm in the
case of even number of sites. Exactly this case is usually considered.

</DOC>
<DOC>
<DOCNO> 150924 </DOCNO>
Lorentz-Covariant Quantization of Massless Non-Abelian Gauge Fields in


  The Lorentz-covariant quantization performed in the Hamiltonian path-integral
formalism for massless non-Abelian gauge fields has been achieved. In this
quantization, the Lorentz condition, as a constraint, must be introduced
initially and incorporated into the Yang-Mills Lagrangian by the Lagrange
undetermined multiplier method. In this way, it is found that all Lorentz
components of a vector potential have thier corresponding conjugate canonical
variables. This fact allows us to define Lorentz-invariant poisson brackets and
carry out the quantization in a Lorent-covariant manner. Key words: Non-Abelian
gauge field, quantization, Hamiltonian path-integral formalism, Lorentz
covariance.

</DOC>
<DOC>
<DOCNO> 8278 </DOCNO>
Alkali specific effects in superconducting fullerides: the observation


  Electron Spin Resonance and optical reflectivity measurements demonstrate a
metal-insulator transition in Na_2CsC_60 as the system passes from the low
temperature simple cubic to the high temperature {\it fcc} structure above 300
K. The non-conducting electronic state is especially unexpected in view of the
metallic character of other, apparently isostructural fullerides, like K_3C_60.
The occurence of this phase in Na_2CsC_60 suggests that alkali specific effects
can not be neglected in the description of the electronic properties of alkali
doped fullerides. We discuss the origin of the insulating state and the
relevance of our results for the anomaly observed in the magnitude of the
superconducting transition temperature of Na_2AC_60 fullerides.

</DOC>
<DOC>
<DOCNO> 121631 </DOCNO>
Linear and nonlinear contributions to pairwise peculiar velocities


  We write the correlation function of dark matter particles, xi(r), as the sum
of two terms - one which accounts for nonlinear evolution, and dominates on
small scales, and another which is essentially the term from linear theory, and
dominates on large scales. We use models of the number and spatial distribution
of haloes and halo density profiles to describe the nonlinear term and its
evolution. The result provides a good description of the evolution of xi(r) in
simulations. We then use this decomposition to provide simple and accurate
models of how the single particle velocity dispersion evolves with time, and
how the first and second moments of the pairwise velocity distribution depend
on scale. The key idea is to use the simple physics of linear theory on large
scales, the simple physics of the virial theorem on small scales, and our model
for the correlation function to tell us how to weight the two types of
contributions (linear and nonlinear) to the pairwise velocity statistics. When
incorporated into the streaming model, our results will allow a simple accurate
description of redshift-space distortions over the entire range of linear to
highly nonlinear regimes.

</DOC>
<DOC>
<DOCNO> 68686 </DOCNO>
The Lambda_b lifetime in the light front quark model


  The enhancement of the Lambda_b decay width relative to B decay one due to
the difference of Fermi motion effects in Lambda_b and B is calculated in the
light--front quark model with the simplifying assumption that Lambda_b consists
of the heavy quark and light scalar diquark. In order to explain the large
deviation from unity in the experimental result for tau(Lambda_b)/tau(B), it is
necessary that diquark be light and the ratio of the squares of the Lambda_b
and B wave functions at the origin be \le 1.

</DOC>
<DOC>
<DOCNO> 100937 </DOCNO>
Blowup formulae in Donaldson-Witten theory and integrable hierarchies


  We investigate blowup formulae in Donaldson-Witten theory with gauge group
SU(N), using the theory of hyperelliptic Kleinian functions. We find that the
blowup function is a hyperelliptic sigma-function and we describe an explicit
procedure to expand it in terms of the Casimirs of the gauge group up to
arbitrary order. As a corollary, we obtain a new expression for the contact
terms and we show that the correlation functions involving the exceptional
divisor are governed by the KdV hierarchy. We also show that, for manifolds of
simple type, the blowup function becomes a tau-function for a multisoliton
solution.

</DOC>
<DOC>
<DOCNO> 102312 </DOCNO>
First-hit analysis of algorithms for computing quadratic irregularity


  The author has previously extended the theory of regular and irregular primes
to the setting of arbitrary totally real number fields. It has been conjectured
that the Bernoulli numbers, or alternatively the values of the Riemann zeta
function at odd negative integers, are evenly distributed modulo p for every p.
This is the basis of a well-known heuristic given by Siegel for estimating the
frequency of irregular primes. So far, analyses have shown that if Q(\sqrt{D})
is a real quadratic field, then the values of the zeta function
\zeta_{D}(1-2m)=\zeta_{Q(\sqrt{D})}(1-2m) at negative odd integers are also
distributed as expected modulo p for any p. We use this heuristic to predict
the computational time required to find quadratic analogues of irregular primes
with a given order of magnitude. We also discuss alternative ways of collecting
large amounts of data to test the heuristic.

</DOC>
<DOC>
<DOCNO> 119077 </DOCNO>
Observations of Mira stars with the IOTA/FLUOR interferometer and


  We present K-band observations of five Mira stars with the IOTA
interferometer. The interferograms were obtained with the FLUOR fiber optics
beam combiner which provides high-accuracy visibility measurements in spite of
time-variable atmospheric conditions. For the Mira stars X Oph, R Aql, RU Her,
R Ser, and V CrB we derived the uniform-disk diameters 11.7 mas, 10.9 mas, 8.4
mas, 8.1 mas, and 7.9 mas (+/-0.3 mas), respectively. Simultaneous photometric
observations yielded the bolometric fluxes. The derived angular Rosseland radii
and the bolometric fluxes allowed the determination of effective temperatures.
For instance, the effective temperature of R Aql was determined to be 3072 K
+/- 161 K. A Rosseland radius for R Aql of 250 Rsun +/- 63 Rsun was derived
from the angular Rosseland radius of 5.5 mas +/- 0.2 mas and the HIPPARCOS
parallax of 4.73 mas +/- 1.19 mas. The observations were compared with
theoretical Mira star models of Bessel, Scholz and Wood (1996) and Hofmann,
Scholz and Wood (1998).

</DOC>
<DOC>
<DOCNO> 123244 </DOCNO>
Searching for Baryons with Chandra


  At low redshifts, measurements of the total baryon content in stars, atomic
and molecular hydrogen, and cluster gas fall a factor of two to four below the
baryon density derived from observed light-element ratios and nucleosynthesis
arguments. A possible hiding place for a significant fraction of the missing
baryons is in the warm/hot gas at temperatures T = 10^{5}-10^{7}K. We present
predictions of the contribution to the soft X-ray background from warm/hot gas
emission calculated using new hydrodynamical simulations and discuss the
possibility of detecting the spectral signature of this gas using the Chandra
X-ray Observatory.

</DOC>
<DOC>
<DOCNO> 119070 </DOCNO>
3C radio sources as they've never been seen before


  Low-radio-frequency observations played a remarkable role in the early days
of radio astronomy; however, in the subsequent three or four decades their
usefulness has largely been in terms of the finding-frequency of surveys.
Recent technical innovation at the VLA has meant that spatially well-resolved
imaging at low frequencies is now possible. Such imaging is essential to
understanding the relationship between the hotspot and lobe emission in
classical double radio sources, for example. We here present new images of 3C
radio sources at 74 MHz and 330 MHz and discuss their implications.

</DOC>
<DOC>
<DOCNO> 70326 </DOCNO>
CP violating supersymmetric contributions to the electroweak $\rho$


  Effects of CP violation on the supersymmetric electroweak correction to the
$\rho$ parameter are investigated. To avoid the EDM constraints, we require
that arg$(\mu)<10^{-2}$ and the non-universal trilinear couplings
$A_f=(0,0,A_0)$ and also assume that gluinos are heavier than 400 GeV. The CP
phase $\phi_t=$ arg($A_0$) leads to large enhancement of the relative mass
splittings between $\tilde{t}_2$ and $\tilde{b}_L(\tilde{t}_1)$, which in turn
reduces the one-loop contribution of the stop and sbottom to $\Delta \rho$. For
small $\tan \beta$, such a CP violating effect is prominent. We also study how
much the two-loop gluon and gluino contributions are affected by the CP phase.
Possible contributions to the $\rho$ parameter arising from the Higgs sector
with CP violation are discussed.

</DOC>
<DOC>
<DOCNO> 152502 </DOCNO>
Noncommutative Parameters of Quantum Symmetries and Star Products


  The star product technique translates the framework of local fields on
noncommutative space-time into nonlocal fields on standard space-time. We
consider the example of fields on $\kappa$- deformed Minkowski space,
transforming under $\kappa$-deformed Poincar\'{e} group with noncommutative
parameters. By extending the star product to the tensor product of functions on
$\kappa$-deformed Minkowski space and $\kappa$-deformed Poincar\'{e} group we
represent the algebra of noncommutative parameters of deformed relativistic
symmetries by functions on classical Poincar\'{e} group.

</DOC>
<DOC>
<DOCNO> 70726 </DOCNO>
Does the $D^-/D^+$ production asymmetry decrease at large $x_F$?


  We have applied the meson cloud model (MCM) to calculate the asymmetries in
$D$ and $D_s$ meson production in high energy $\Sigma^-$-nucleus and
$\pi^-$-nucleus collisions. We find a good agreement with recent data. Our
results suggest that the asymmetries may decrease at large $x_F$.

</DOC>
<DOC>
<DOCNO> 10251 </DOCNO>
Theory of Electron Differentiation, Flat Dispersion and Pseudogap


  Aspects of electron critical differentiation are clarified in the proximity
of the Mott insulator. The flattening of the quasiparticle dispersion appears
around momenta $(\pi,0)$ and $(0,\pi)$ on square lattices and determines the
criticality of the metal-insulator transition with the suppressed coherence in
that momentum region of quasiparticles. Such coherence suppression at the same
time causes an instability to the superconducting state if a proper incoherent
process is retained. The d-wave pairing interaction is generated from such
retained processes without disturbance from the coherent single-particle
excitations. Pseudogap phenomena widely observed in the underdoped cuprates are
then naturally understood from the mode-mode coupling of d-wave
superconducting(dSC) fluctuations with antiferromagnetic ones. When we assume
the existence of a strong d-wave pairing force repulsively competing with
antiferromagnetic(AFM) fluctuations under the formation of flat and damped
single-particle dispersion, we reproduce basic properties of the pseudogap seen
in the magnetic resonance, neutron scattering, angle resolved photoemission and
tunneling measurements in the cuprates.

</DOC>
<DOC>
<DOCNO> 118410 </DOCNO>
The ROSAT Bright Survey: II. Catalogue of all high-galactic latitude


  We present a summary of an identification program of the more than 2000 X-ray
sources detected during the ROSAT All-Sky Survey (Voges et al. 1999) at high
galactic latitude, |b| > 30 degr, with countrate above 0.2 s-1. This program,
termed the ROSAT Bright Survey RBS, is to more than 99.5% complete. A
sub-sample of 931 sources with countrate above 0.2 s-1 in the hard spectral
band between 0.5 and 2.0 keV is to 100% identified. The total survey area
comprises 20391 sq.deg at a flux limit of 2.4 \times 10^{-12} erg/cmsq/s in the
0.5 -- 2.0 keV band. About 1500 sources of the complete sample could be
identified by correlating the RBS with SIMBAD and the NED. The remaining 500
sources were identified by low-resolution optical spectroscopy and CCD imaging
utilizing telescopes at La Silla, Calar Alto, Zelenchukskaya and Mauna Kea.
Apart from completely untouched sources, catalogued clusters and galaxies
without published redshift as well as catalogued galaxies with unusual high
X-ray luminosity were included in the spectroscopic identification program.
Details of the observations with an on-line presentation of the finding charts
and the optical spectra will be published separately. Here we summarize our
identifications in a table which contains optical and X-ray information for
each source. As a result we present the most massive complete sample of X-ray
selected AGNs with a total of 669 members and a well populated X-ray selected
sample of 302 clusters of galaxies with redshifts up to 0.70. Three fields
studied by us remain without optical counterpart (RBS0378, RBS1223, RBS1556).
While the first is a possible X-ray transient, the two latter are isolated
neutron star candidates (Motch et al. 1999, Schwope et al. 1999).

</DOC>
<DOC>
<DOCNO> 150441 </DOCNO>
Partial supersymmetry breaking in Multidimensional N=4 SUSY QM


  The multidimensional N=4 supersymmetric quantum mechanics (SUSY QM) is
constructed and the various possibilities for partial supersymmetry breaking
are discussed. It is shown that quantum mechanical models with one quarter, one
half and three quarters of unbroken(broken) supersymmetries can exist in the
framework of the multidimensional N=4 SUSY QM.

</DOC>
<DOC>
<DOCNO> 118930 </DOCNO>
General Relativistic Constraints on Emission Models of Anomalous X-ray


  Most models of anomalous X-ray pulsars (AXPs) account for the observed X-ray
spectra and pulsations by means of radiation processes that occur on the
surfaces of neutron stars. For any such model, general relativistic deflection
of light severely suppresses the amplitude of the observed pulsations. We
calculate the expected pulsation amplitudes of AXPs according to various models
and compare the results with observations. We show that the high (<= 70%) pulse
amplitudes observed in some AXPs can be accounted for only if the surface
emission is localized (spot radius <40 degrees) and strongly beamed
(cos^n[theta'] with n>2, where theta' is the angle to the normal). These
constraints are incompatible with those cooling and magnetar models in which
the observed X-rays originate as thermal emission from the neutron-star
surface. Accretion models, on the other hand, are compatible with observations
for a wide range of parameters. Finally, definitive conclusions cannot be
reached on magnetospheric models, since their localization and beaming
properties are not well understood.

</DOC>
<DOC>
<DOCNO> 121557 </DOCNO>
On the matter entrainment by stellar jets and the acceleration of


  We study, by numerical simulations, the entrainment process in a supersonic,
radiative jet flow, during the evolution of Kelvin-Helmholtz instabilities, in
the context of the the acceleration problem of molecular bipolar outflows,
observed in Giant Molecular Clouds. Our results show that a large fraction of
the initial jet momentum can be transferred to the ambient medium by this
process. We therefore analyze in detail the instability evolution and compare
some of the main observational properties of molecular outflows with those of
the entrained material that we observe in our simulations. In particular, we
find a good agreement for the mass vs. velocity distribution and for the
outflow collimation structure, especially when a light jet is moving into a
denser ambient medium. This is probably the case for (obscured) optical jets
driving powerful molecular outflows in the denser environment of the inner
regions of molecular clouds.

</DOC>
<DOC>
<DOCNO> 178828 </DOCNO>
Will Strangeness Win the Prize?


  Five groups have made predictions involving the production of strange hadrons
and entered them in a competition set up by Barbara Jacak, Xin-Nian Wang and
myself in the spring of 1998 for the purpose of comparing to first year physics
results from RHIC. These predictions are summarized and evaluated.

</DOC>
<DOC>
<DOCNO> 13561 </DOCNO>
Bethe approximation for self-interacting lattice trees


  In this paper we develop a Bethe approximation, based on the cluster
variation method, which is apt to study lattice models of branched polymers. We
show that the method is extremely accurate in cases where exact results are
known as, for instance, in the enumeration of spanning trees. Moreover, the
expressions we obtain for the asymptotic number of spanning trees and lattice
trees on a graph coincide with analogous expressions derived through different
approaches. We study the phase diagram of lattice trees with nearest-neighbour
attraction and branching energies. We find a collapse transition at a
tricritical theta point, which separates an expanded phase from a compact
phase. We compare our results for the theta transition in two and three
dimensions with available numerical estimates.

</DOC>
<DOC>
<DOCNO> 150820 </DOCNO>
On (b,c)-system at finite temperature in thermo field approach


  We construct the finite temperature field theory of the two-dimensional
ghost-antighost system within the framework of thermo field theory.

</DOC>
<DOC>
<DOCNO> 7615 </DOCNO>
Universal Transverse Conductance between Quantum Hall Regions and (2+1)D


  Using bosonization techniques for (2+1)D systems, we show that the transverse
conductance for a system with general current interactions, when measured
between perfect Hall regions is not renormalized at low temperatures. Our
method extends and combines two results we have recently obtained on low
dimensional fermionic systems: on the one hand, the relationship between
universality of Landauer conductance and universality of bosonization rules for
(1+1)D systems, and on the other hand, the universal character of the bosonized
topological current associated to a (2+1)D fermionic system with current
interaction.

</DOC>
<DOC>
<DOCNO> 68641 </DOCNO>
Non-uniform chiral phase in effective chiral quark models


  We analyze the phase diagram in effective chiral quark models (the
Nambu-Jona-Lasinio model, the sigma-model with quarks) and show that at the
mean-field level a phase with a periodically-modulated chiral fields separates
the usual phases with broken and restored chiral symmetry. A possible signal of
such a phase is the production of multipion jets travelling in opposite
directions, with individual pions having momenta of the order of several
hundred MeV. This signal can be interpreted in terms of disoriented chiral
condensates.

</DOC>
<DOC>
<DOCNO> 12190 </DOCNO>
Examining the Connection between Gauge Invariance and the Integral


  We show the inconsistency of the argument linking the integral quantum Hall
effect to gauge invariance. The inconsistency mainly consists of equating gauge
and real vector potential transformations for a particular system geometry.
Correct handling gives no Hall quantization.

</DOC>
<DOC>
<DOCNO> 68779 </DOCNO>
The mixing of the f0(1370), f0(1500) and f0(1710) and the search for the


  For the first time a complete data set of the two-body decays of the
f0(1370), f0(1500) and f0(1710) into all pseudoscalar mesons is available. The
implications of these data for the flavour content for these three f0 states is
studied. We find that they are in accord with the hypothesis that the scalar
glueball of lattice QCD mixes with the qqbar nonet that also exists in its
immediate vicinity. We show that this solution also is compatible with the
relative production strengths of the f0(1370), f0(1500) and f0(1710) in pp
central production, ppbar annihilations and J/psi radiative decays.

</DOC>
<DOC>
<DOCNO> 152190 </DOCNO>
Phase Transition in the Higgs Model of Scalar Fields with Electric and


  Using a one-loop renormalization group improvement for the effective
potential in the Higgs model of electrodynamics with electrically and
magnetically charged scalar fields, we argue for the existence of a triple
(critical) point in the phase diagram ($\lambda_{run}, g_{run}^4$), where
$\lambda_{run}$ is the renormalised running selfinteraction constant of the
Higgs scalar monopoles and $g_{run}$ is their running magnetic charge. This
triple point is a boundary point of three first-order phase transitions in the
dual sector of the Higgs scalar electrodynamics: The "Coulomb" and two
confinement phases meet together at this critical point. Considering the
arguments for the one-loop approximation validity in the region of parameters
around the triple point A we have obtained the following triple point values of
the running couplings: $(\lambda_{(A)}, g^2_{(A)})\approx(-13.4; 18.6)$, which
are independent of the electric charge influence and two--loop corrections to
$g^2_{run}$ with high accuracy of deviations. At the triple point the mass of
monopoles is equal to zero. The corresponding critical value of the electric
fine structure constant turns out to be $\alpha_{crit} =
\pi/g^2_{(A)}\approx{0.17}$ by the Dirac relation. This value is close to the
$\alpha_{crit}^{lat}\approx{0.20\pm 0.015}$, which in a U(1) lattice gauge
theory corresponds to the phase transition between the "Coulomb" and
confinement phases. In our theory for $\alpha \ge \alpha_{crit}$ there are two
phases for the confinement of the electrically charged particles. The results
of the present paper are very encouraging for the Anti--grand unification
theory which was developed previously as a realistic alternative to SUSY GUTs.
The paper is also devoted to the discussion of this problem.

</DOC>
<DOC>
<DOCNO> 7981 </DOCNO>
Dipolar Interactions and Origin of Spin Ice in Ising Pyrochlore Magnets


  Recent experiments suggest that the Ising pyrochlore magnets ${\rm
Ho_{2}Ti_{2}O_{7}}$ and ${\rm Dy_{2}Ti_{2}O_{7}}$ display qualitative
properties of the spin ice model proposed by Harris {\it et al.} \prl {\bf 79},
2554 (1997). We discuss the dipolar energy scale present in both these
materials and consider how they can display spin ice behavior {\it despite} the
presence of long range interactions. Specifically, we present numerical
simulations and a mean field analysis of pyrochlore Ising systems in the
presence of nearest neighbor exchange and long range dipolar interactions. We
find that two possible phases can occur, a long range ordered antiferromagnetic
one and the other dominated by spin ice features. Our quantitative theory is in
very good agreement with experimental data on both ${\rm Ho_{2}Ti_{2}O_{7}}$
and ${\rm Dy_{2}Ti_{2}O_{7}}$. We suggest that the nearest neighbor exchange in
${\rm Dy_{2}Ti_{2}O_{7}}$ is {\it antiferromagnetic} and that spin ice behavior
is induced by long range dipolar interactions.

</DOC>
<DOC>
<DOCNO> 117977 </DOCNO>
Superluminal Caustic is Just a Common Misconception: A Comment on


  When angular objects in lensing are considered as linear objects, interesting
phenomena start happening. Tachyonic caustics are one example. We review that
the intrinsic variables of the lens equation are angular variables. We argue
that the "fast glance effect" of a caustic curve that is far away from lenses
does not share the physical bearing of the well-known (apparent) superluminal
motion. There is no dbout that it would be a useful exercise to study the null
geodesics in the metric of, say, a rapidly rotating black hole binary.
Lienard-Wiechert potentials ($A_\mu$) satisfy Maxwell's equations in Minkowski
space. Authors' claim that swapping eQ and GM makes the time component ($A_0$)
of the Lienard-Wiechert potentials into "the gravitational analog" that governs
the behavior of the null geodesics near a relativistic binary system seems to
be unfounded.

</DOC>
<DOC>
<DOCNO> 71570 </DOCNO>
Introduction to Diffractive Photoprocesses


  The objectives of my talk are to provide a very brief introduction to
diffractive photoprocesses in general and the colour dipole model in
particular; and to comment on possible gluon saturation effects at HERA and
beyond.

</DOC>
<DOC>
<DOCNO> 117719 </DOCNO>
Transformations between the theoretical and observational planes in the


  Color-temperature relations and bolometric corrections in the HST-NICMOS
F1110W, F160W and F222M and in the WFPC2 F439W, F555W and F814W photometric
systems, using two different sets of model atmospheres, have been derived. This
database of homogeneous, self-consistent transformations between the
theoretical and observational planes also allows combinations of visual and
infrared quantities, without any further transformation between the two
different photometric systems. The behavior of the inferred quantities with
varying the stellar parameters, the adopted model atmospheres and the
instrumental configurations are investigated. Suitable relations to transform
colors and bolometric corrections from HST to ground-based photometric systems
are also provided.

</DOC>
<DOC>
<DOCNO> 170384 </DOCNO>
On the class of languages recognizable by 1-way quantum finite automata


  It is an open problem to characterize the class of languages recognized by
quantum finite automata (QFA). We examine some necessary and some sufficient
conditions for a (regular) language to be recognizable by a QFA. For a subclass
of regular languages we get a condition which is necessary and sufficient.
  Also, we prove that the class of languages recognizable by a QFA is not
closed under union or any other binary Boolean operation where both arguments
are significant.

</DOC>
<DOC>
<DOCNO> 67930 </DOCNO>
Perturbative calculation of the scaled factorial moments in second-order


  The scaled factorial moments $F_q$ are studied for a second-order
quark-hadron phase transition within the Ginzburg-Landau description. The role
played by the ground state of the system under low temperature is emphasized.
After a local shift of the order parameter the fluctuations are around the
ground state, and a perturbative calculation for $F_q$ can be carried out.
Power scaling between $F_q$'s is shown, and a universal scaling exponent
$\nu\simeq 1.75$ is given for the case with weak correlations and weak
self-interactions.

</DOC>
<DOC>
<DOCNO> 85117 </DOCNO>
Does Dark Matter Exist?


  The success of the Lambda-CDM model on large scales does not extend down to
galaxy scales. We list a dozen problems of the dark matter hypothesis, some of
which arise in specific models for the formation of structure in the universe,
while others are generic and require fine tuning in any dark matter theory.
Modifications to the theory, such as adding properties to the DM particles
beyond gravitational interactions, or simply a better understanding of the
physics of galaxy formation, may resolve some problems, but a number of
conspiracies and correlations are unlikely to yield to this approach. The
alternative is that mass discrepancies result from of a non-Newtonian law of
gravity, a hypothesis which avoids many of the more intractable problems of
dark matter. A modified law of gravity is not without formidable difficulties
of its own, but it is no longer obvious that they are any more daunting than
those facing DM.

</DOC>
<DOC>
<DOCNO> 121022 </DOCNO>
Magnetic Extraction of Spin Energy from a Black Hole


  Numerous variations have been proposed on the original suggestion by
Blandford and Znajek that magnetic fields could be used to extract rotational
energy from black holes. A new categorization of these variations is proposed
so that they may be considered in a systematic way. "Black hole spindown" is
defined more precisely, distinguishing decrease in the spin parameter a/M from
decreases in angular momentum a and rotational kinetic energy, M - M_i. Several
key physical questions are raised: Can the "stretched horizon" of a black hole
communicate with the outside world? Do accretion disks bring any net magnetic
flux to the black holes at their centers? Is the magnetic field adjacent to a
black hole force-free everywhere?

</DOC>
<DOC>
<DOCNO> 40166 </DOCNO>
Measurement of Bose-Einstein Correlations in e+e- -> W+W- at


  We investigate Bose-Einstein correlations (BEC) in W-pair production at
root(s)=189GeV using the L3 detector at LEP. We observe BEC between particles
from a single W decay in good agreement with those from a light-quark Z decay
sample. We investigate their possible existence between particles coming from
different W's. No evidence for such inter-W BEC is found.

</DOC>
<DOC>
<DOCNO> 12081 </DOCNO>
Order-parameter fluctuations (OPF) in spin glasses: Monte Carlo


  The use of parameters measuring order-parameter fluctuations (OPF) has been
encouraged by the recent results reported in \cite{RS} which show that two of
these parameters, $G$ and $G_c$, take universal values in the $\lim_{T\to 0}$.
In this paper we present a detailed study of parameters measuring OPF for two
mean-field models with and without time-reversal symmetry which exhibit
different patterns of replica symmetry breaking below the transition: the
Sherrington-Kirkpatrick model with and without a field and the Ising p-spin
glass (p=3). We give numerical results and analyze the consequences which
replica equivalence imposes on these models in the infinite volume. We give
evidence for the transition in each system and discuss the character of
finite-size effects. Furthermore, a comparative study between this new family
of parameters and the usual Binder cumulant analysis shows what kind of new
information can be extracted from the finite $T$ behavior of these quantities.
The two main outcomes of this work are: 1) Parameters measuring OPF give better
estimates than the Binder cumulant for $T_c$ and even for very small systems
they give evidence for the transition. 2) For systems with no time-reversal
symmetry, parameters defined in terms of connected quantities are the proper
ones to look at.

</DOC>
<DOC>
<DOCNO> 10064 </DOCNO>
From Noncommutative Bosonization to S-Duality


  We extend standard path-integral techniques of bosonization and duality to
the setting of noncommutative geometry. We start by constructing the
bosonization prescription for a free Dirac fermion living in the noncommutative
plane R_\theta^2. We show that in this abelian situation the fermion theory is
dual to a noncommutative Wess-Zumino-Witten model. The non-abelian situation is
also constructed along very similar lines. We apply the techniques derived to
the massive Thirring model on noncommutative R_\theta^2 and show that it is
dualized to a noncommutative WZW model plus a noncommutative cosine potential
(like in the noncommutative Sine-Gordon model). The coupling constants in the
fermionic and bosonic models are related via strong-weak coupling duality. This
is thus an explicit construction of S-duality in a noncommutative field theory.

</DOC>
<DOC>
<DOCNO> 150866 </DOCNO>
Superworldvolume dynamics of superbranes from nonlinear realizations


  Based on the concept of the partial breaking of global supersymmetry (PBGS),
we derive the worldvolume superfield equations of motion for $N=1, D=4$
supermembrane, as well as for the space-time filling D2- and D3-branes, from
nonlinear realizations of the corresponding supersymmetries. We argue that it
is of no need to take care of the relevant automorphism groups when being
interested in the dynamical equations. This essentially facilitates
computations. As a by-product, we obtain a new polynomial representation for
the $d=3,4$ Born-Infeld equations, with merely a cubic nonlinearity.

</DOC>
<DOC>
<DOCNO> 68126 </DOCNO>
Relativistic Symmetry Suppresses Quark Spin-Orbit Splitting


  Experimental data indicate small spin-orbit splittings in hadrons. For
heavy-light mesons we identify a relativistic symmetry that suppresses these
splittings. We suggest an experimental test in electron-positron annihilation.
Furthermore, we argue that the dynamics necessary for this symmetry are
possible in QCD.

</DOC>
<DOC>
<DOCNO> 71714 </DOCNO>
Supersymmetric seesaw model for the (1+3)-scheme of neutrino masses


  A four-neutrino spectrum with a sterile neutrino without significant
involvement in the atmospheric and solar neutrino oscillation experiments has
been recently advocated as the correct picture to explain all existing
experimental data. We propose a supersymmetric model in which this picture can
be naturally implemented. In this model, the mass for the mainly active
neutrino eigenstates is induced by the seesaw mechanism with a large
intermediate scale $M_R$, whereas the mass for the mainly sterile neutrino
state is closely related to supersymmetry breaking.

</DOC>
<DOC>
<DOCNO> 151917 </DOCNO>
Inertial Mass and Vacuum Fluctuations in Quantum Field Theory


  After recalling the different ways to define inertial mass of elementary
particles in modern physics, we study the relationship between the mass of
charged particles and zero-point electromagnetic fields. To this end we first
introduce a simple model comprising a scalar field immersed in stochastic or
thermal electromagnetic fields. Then we sketch the main steps of Feynman mass
renormalization procedure. Our approach is essentially pedagogical and in line
with the standard formalism of quantum field theory, but we also try to keep an
open mind concerning the physical interpretation. We check, for instance, if it
is possible to start from a zero bare mass in the renormalization process and
express the finite physical mass in terms of a cut-off. Finally we briefly
recall the Casimir-induced mass modification of conducting or dielectric
bodies.

</DOC>
<DOC>
<DOCNO> 170438 </DOCNO>
On the Number of Elements Needed in a POVM Attaining the Accessible


  We investigate a symmetric set of three quantum states in three dimensions
having interesting properties, which we call the lifted trine states. We show
that for the ensemble consisting of the three lifted trine states taken with
equal probabilities, the POVM measurement realizing the accessible information
must contain six projectors, giving a counterexample to a conjecture of
Levitin.

</DOC>
<DOC>
<DOCNO> 12010 </DOCNO>
Supported Membranes on Chemically Structured and Rough Surfaces


  We present a general linear response description of membrane adhesion at
rough or chemically structured surfaces. Our method accounts for non-local Van
der Waals effects and contains the more approximate (and local) Deryagin
approach in a simple limit. Specializing to supported membranes we consider the
effects of substrate structure on the membrane adhesion energy and
configuration. Adhesion is usually less favorable for rough substrates and the
membrane shape tends to follow that of the surface contours. Chemical
patterning, however, favors adhesion with the membrane configuration being out
of phase with the surface structure. Finally, considering a surface indented
with `V'-shaped trenches, we show that our approach is in fair agreement with
an exact numerical solution.

</DOC>
<DOC>
<DOCNO> 117898 </DOCNO>
CO on Titan: More Evidence for a Well-Mixed Vertical Profile


  We report new interferometric observations of the CO (2-1) rotational
transition on Titan. We find that the spectrum is best fit by a uniform profile
of 52 ppm, with estimated errors of 6 ppm (40 to 200 km) and 12 ppm (200 to 300
km).

</DOC>
<DOC>
<DOCNO> 9848 </DOCNO>
Dynamics and transport in random quantum systems governed by


  We present results on the low-frequency dynamical and transport properties of
random quantum systems whose low temperature ($T$), low-energy behavior is
controlled by strong disorder fixed points. We obtain the momentum and
frequency dependent dynamic structure factor in the Random Singlet (RS) phases
of both spin-1/2 and spin-1 random antiferromagnetic chains, as well as in the
Random Dimer (RD) and Ising Antiferromagnetic (IAF) phases of spin-1/2 random
antiferromagnetic chains. We show that the RS phases are unusual `spin metals'
with divergent low-frequency spin conductivity at T=0, and we also follow the
conductivity through novel `metal-insulator' transitions tuned by the strength
of dimerization or Ising anisotropy in the spin-1/2 case, and by the strength
of disorder in the spin-1 case. We work out the average spin and energy
autocorrelations in the one-dimensional random transverse field Ising model in
the vicinity of its quantum critical point. All of the above calculations are
valid in the frequency dominated regime $\omega \agt T$, and rely on previously
available renormalization group schemes that describe these systems in terms of
the properties of certain strong-disorder fixed point theories. In addition, we
obtain some information about the behavior of the dynamic structure factor and
dynamical conductivity in the opposite `hydrodynamic' regime $\omega < T$ for
the special case of spin-1/2 chains close to the planar limit (the quantum x-y
model) by analyzing the corresponding quantities in an equivalent model of
spinless fermions with weak repulsive interactions and particle-hole symmetric
disorder.

</DOC>
<DOC>
<DOCNO> 12955 </DOCNO>
Subleading long-range interactions and violations of finite size scaling


  We study the behavior of systems in which the interaction contains a
long-range component that does not dominate the critical behavior. Such a
component is exemplified by the van der Waals force between molecules in a
simple liquid-vapor system. In the context of the mean spherical model with
periodic boundary conditions we are able to identify, for temperatures close
above $T_c$, finite-size contributions due to the {\it subleading} term in the
interaction that are {\it dominant} in this region decaying algebraically as a
function of $L$. This mechanism goes beyond the standard formulation of the
finite-size scaling but is to be expected in real physical systems. We also
discuss other ways in which critical point behavior is modified that are of
relevance for analysis of Monte Carlo simulations of such systems.

</DOC>
<DOC>
<DOCNO> 116255 </DOCNO>
Statistical mechanics of neocortical interactions: EEG eigenfunctions of


  This paper focuses on how bottom-up neocortical models can be developed into
eigenfunction expansions of probability distributions appropriate to describe
short-term memory in the context of scalp EEG. The mathematics of
eigenfunctions are similar to the top-down eigenfunctions developed by Nunez,
albeit they have different physical manifestations. The bottom-up
eigenfunctions are at the local mesocolumnar scale, whereas the top-down
eigenfunctions are at the global regional scale. However, as described in
several joint papers, our approaches have regions of substantial overlap, and
future studies may expand top-down eigenfunctions into the bottom-up
eigenfunctions, yielding a model of scalp EEG that is ultimately expressed in
terms of columnar states of neocortical processing of attention and short-term
memory.

</DOC>
<DOC>
<DOCNO> 68862 </DOCNO>
Large Quark Rotations, Neutrino mixing and Proton Decay


  Right-handed (RH) rotations do not play a role in the Standard Model, and
only the differences of the LH mixing angles are involved in ${\bf V}_{\scr
\textrm{CKM}}$. This leads to the huge freedom in the fermionic mass matrices.
However, that is no more true in extensions of the Standard Model. For example
in GUTs large RH rotations of the quarks can be related to the observed large
neutrino mixing or in particular, all mixing angles are relevant for the proton
decay. We present a simple realistic non-SUSY SO(10) GUT with large RH and LH
mixing and study the corresponding nucleon decay rates.

</DOC>
<DOC>
<DOCNO> 169596 </DOCNO>
Canonical pairs, Spatially Confined Motion and the Quantum Time of


  It has always been believed that no self-adjoint and canonical time of
arrival operator can be constructed within the confines of standard quantum
mechanics. In this Letter we demonstrate the otherwise. We do so by pointing
out that there is no a priori reason in demanding that canonical pairs form a
system of imprimitivities. We then proceed to show that a class of self-adjoint
and canonical time of arrival (TOA) operators can be constructed for a
spatially confined free particle. And then discuss the relatiobship between the
non-self-adjointess of the TOA operator for the unconfined particle and the
self-adjointness of the confined one.

</DOC>
<DOC>
<DOCNO> 13968 </DOCNO>
The Non-Abelian Density Matrix Renormalization Group Algorithm


  We describe here the extension of the density matrix renormalization group
algorithm to the case where Hamiltonian has a non-Abelian global symmetry
group. The block states transform as irreducible representations of the
non-Abelian group. Since the representations are multi-dimensional, a single
block state in the new representation corresponds to multiple states of the
original density matrix renormalization group basis. We demonstrate the
usefulness of the construction via the one-dimensional Hubbard model as the
symmetry group is enlarged from $U(1) \times U(1)$, up to $SU(2) \times SU(2)$.

</DOC>
<DOC>
<DOCNO> 99791 </DOCNO>
Entropy-driven phase transitions in multitype lattice gas models


  In multitype lattice gas models with hard-core interaction of
Widom--Rowlinson type, there is a competition between the entropy due to the
large number of types, and the positional energy and geometry resulting from
the exclusion rule and the activity of particles. We investigate this
phenomenon in four different models on the square lattice: the multitype
Widom-Rowlinson model with diamond-shaped resp. square-shaped exclusion between
unlike particles, a Widom-Rowlinson model with additional molecular exclusion,
and a continuous-spin Widom-Rowlinson model. In each case we show that this
competition leads to a first-order phase transition at some critical value of
the activity, but the number and character of phases depend on the geometry of
the model. Our technique is based on reflection positivity and the chessboard
estimate.

</DOC>
<DOC>
<DOCNO> 116704 </DOCNO>
Laser generated wake fields as a new diagnostic tool for magnetized


  In the presence of an external magnetic field, wake fields generated by a
short laser pulse can propagate out of the plasma, and thereby provide
information about the electron density profile. A method for reconstructing the
density profile from a measured wake field spectrum is proposed and a numerical
example is given. Finally, we compare our proposal with existing plasma density
diagnostic techniques.

</DOC>
<DOC>
<DOCNO> 68717 </DOCNO>
Jet Activity in t-tbar Events and Top Mass Reconstruction at Hadron


  We analyse the impact of matrix-element corrections to top decays in HERWIG
on several observables related to the jet activity in t-tbar events at the
Tevatron and at the LHC. In particular, we study the effects induced by the
higher-order corrections to top decays on the top mass reconstruction using the
recently proposed J/psi+lepton final states.

</DOC>
<DOC>
<DOCNO> 9865 </DOCNO>
Naudts-like duality and the extreme Fisher information principle


  We show that using the most parsimonious version of Frieden and Soffer's
extreme information principle (EPI) with a Fisher measure constructed with
escort probabilities, the concomitant solutions obey a type of Naudts' duality
for nonextensive ensembles. We also determine in closed form the general
(normalized) probability distribution that minimizes Fisher's information.

</DOC>
<DOC>
<DOCNO> 150674 </DOCNO>
The Holographic Principle


  After a pedagogical overview of the present status of High-Energy Physics,
some problems concerning physics at the Planck scale are formulated, and an
introduction is given to a notion that became known as ``the holographic
principle" in Planck scale physics, which is arrived at by studying quantum
mechanical features of black holes.

</DOC>
<DOC>
<DOCNO> 120255 </DOCNO>
Dual-Frequency VSOP Observations of AO 0235+164


  AO 0235+164 is a very compact, flat spectrum radio source identified as a BL
Lac object at a redshift of z=0.94. It is one of the most violently variable
extragalactic objects at both optical and radio wavelengths. The radio
structure of the source revealed by various ground-based VLBI observations is
dominated by a nearly unresolved compact component at almost all available
frequencies.
  Dual-frequency space VLBI observations of AO 0235+164 were made with the VSOP
mission in January-February 1999. The array of the Japanese HALCA satellite and
co-observing ground radio telescopes in Australia, Japan, China and South
Africa allowed us to study AO 0235+164 with an unprecedented angular resolution
at frequencies of 1.6 and 5 GHz. We report on the sub-milliarcsecond structural
properties of the source. The 5-GHz observations led to an estimate of T_B >
5.8 x 10^{13} K for the rest-frame brightness temperature of the core, which is
the highest value measured with VSOP to date.

</DOC>
<DOC>
<DOCNO> 80711 </DOCNO>
Quantum Spin Dynamics (QSD) : VII. Symplectic Structures and Continuum


  Interesting non-linear functions on the phase spaces of classical field
theories can never be quantized immediately because the basic fields of the
theory become operator valued distributions. Therefore, one is usually forced
to find a classical substitute for such a function depending on a regulator
which is expressed in terms of smeared quantities and which can be quantized in
a well-defined way. Namely, the smeared functions define a new symplectic
manifold of their own which is easy to quantize. Finally one must remove the
regulator and establish that the final operator, if it exists, has the correct
classical limit.
  In this paper we investigate these steps for diffeomorphism invariant quantum
field theories of connections. We introduce a generalized projective family of
symplectic manifolds, coordinatized by the smeared fields, which is labelled by
a pair consisting of a graph and another graph dual to it. We show that there
exists a generalized projective sequence of symplectic manifolds whose limit
agrees with the symplectic manifold that one started from.
  This family of symplectic manifolds is easy to quantize and we illustrate the
programme outlined above by applying it to the Gauss constraint. The framework
developed here is the classical cornerstone on which the semi-classical
analysis developed in a new series of papers called ``Gauge Theory Coherent
States'' is based.

</DOC>
<DOC>
<DOCNO> 123199 </DOCNO>
Galactic and extragalactic magnetic fields


  The current state of research of the Galactic magnetic field is reviewed
critically. The average (equipartition) strength of the total field derived
from radio synchrotron data is 6 +/- 2 muG locally and about 10 +/- 3 muG at 3
kpc Galactic radius. These values agree well with the estimates using the
locally measured cosmic-ray energy spectrum and the radial variation of protons
derived from gamma-rays. Optical and synchrotron polarization data yield a
strength of the local regular field of 4 +/- 1 muG, but this value is an upper
limit if the field strength fluctuates within the beam or if anisotropic fields
are present. Pulsar rotation measures, on the other hand, give only 1.4 +/- 0.2
muG, a lower limit if fluctuations in regular field strength and thermal
electron density are anticorrelated along the pathlength. The local regular
field may be part of a 'magnetic arm' between the optical arms. However, the
global structure of the regular Galactic field is not yet known. Several
large-scale field reversals in the Galaxy were detected from rotation measure
data, but a similar phenomenon was not observed in external galaxies. The
Galactic field may be young in terms of dynamo action so that reversals from
the chaotic seed field are preserved, or a mixture of dynamo modes causes the
reversals, or the reversals are signatures of large-scale anisotropic field
loops. The Galaxy is surrounded by a thick disk of radio continuum emission of
similar extent as in edge-on spiral galaxies. While the local field in the thin
disk is of even symmetry with respect to the plane (quadrupole), the global
thick-disk field may be of dipole type. The Galactic center region hosts highly
regular fields of up to milligauss strength which are oriented perpendicular to
the plane.

</DOC>
<DOC>
<DOCNO> 169770 </DOCNO>
Unified approach to quantum capacities: towards quantum noisy coding


  Basing on unified approach to {\it all} kinds of quantum capacities we show
that the rate of quantum information transmission is bounded by the maximal
attainable rate of coherent information. Moreover, we show that, if for any
bipartite state the one-way distillable entanglement is no less than coherent
information, then one obtains Shannon-like formulas for all the capacities. The
inequality also implies that the decrease of distillable entanglement due to
mixing process does not exceed of corresponding loss information about a
system.

</DOC>
<DOC>
<DOCNO> 71161 </DOCNO>
A Lot of Flavor Physics from a Little Symmetry


  Recent neutrino parameter measurements place increasingly stringent
constraints on acceptable supersymmetric theories of flavor. A very fruitful
approach is the application of non-Abelian discrete gauged flavor symmetries
G_f. We discuss a highly successful model using G_f = T' x Z_3, where T' is a
non-Abelian group based on the symmetries of a tetrahedron. This model
reproduces the basic features of the U(2) model, and also predicts neutrino
masses and mixing angles consistent with either the SMA or LMA solutions.

</DOC>
<DOC>
<DOCNO> 121870 </DOCNO>
The Galaxy Populations of X-Ray Detected, Poor Groups


  (Abridged) We determine the quantitative morphology and star formation
properties of galaxies in six nearby X-ray detected, poor groups using
multi-object spectroscopy and wide-field R imaging. We measure structural
parameters for each galaxy by fitting a PSF-convolved, two component model to
their surface brightness profiles. To compare directly the samples, we fade,
smooth, and rebin each galaxy image so that we effectively observe each galaxy
at the same redshift (9000 km/s) and physical resolution (0.87h^(-1) kpc). We
compare results for the groups to a sample of field galaxies. We find that: 1)
Galaxies spanning a wide range in morphological type and luminosity are
well-fit by a de Vaucouleurs bulge with exponential disk profile. 2)
Morphologically classifying these nearby group galaxies by their bulge fraction
(B/T) is fairly robust on average, even when their redshift has increased by up
to a factor of four and the effective resolution of the images is degraded by
up to a factor of five. 3) The fraction of bulge-dominated systems in these
groups is higher than in the field (~50% vs. ~20%). 4) The fraction of
bulge-dominated systems in groups decreases with increasing radius, similar to
the morphology-radius (~density) relation observed in galaxy clusters. 5)
Current star formation in group galaxies is correlated with significant
morphological asymmetry for disk-dominated systems (B/T<0.4). 6) The group
galaxies that are most disk-dominated (B/T<0.2) are less star forming and
asymmetric on average than their counterparts in the field.

</DOC>
<DOC>
<DOCNO> 117773 </DOCNO>
The spatial and age distribution of stellar populations in DDO 190


  The spatial distribution of stellar populations, the star formation history,
and other properties of the dIrr galaxy DDO 190 have been analyzed using
color--magnitude diagrams (CMDs) of about 3900 resolved stars and the Ha fluxes
of HII regions. From the mean color index of the red giant branch, a mean
metallicity [Fe/H]=-2.0 is obtained. The I magnitude of the TRGB has been used
to estimate the distance. DDO 190 is 2.9+/-0.2 Mpc from the Milky Way, 2.1 Mpc
from the M 94 group (CnV-I), 2.4 Mpc from the M 81 group and 2.9 Mpc from the
barycenter of the Local Group, all indicating that it is an isolated, field
galaxy. The surface-brightness distribution of the galaxy is well fitted by
ellipses of ellipticity e=1-a/b=0.1 and P.A.=82deg. The radial star density
distribution follows an exponential law of scale length a=43."4, corresponding
to 611 pc. The Holmberg semi-major axis to mu_B=26.5 is estimated to be
r^B_(26.5)=3.'0. Stellar populations of different ages in DDO 190 show strong
spatial decoupling, the oldest population appearing much more extended than the
youngest. Stars younger than 0.1 Gyr occupy only the central 40'' (0.55 kpc);
stars younger than a few (~4) Gyr extend out to ~80'' (125 kpc), and for larger
galactocentric distances only older stars seem to be present. This behavior is
found in all the dIrr galaxies for which spatially extended studies have been
performed and could be related with the kinematical history of the galaxy.

</DOC>
<DOC>
<DOCNO> 121080 </DOCNO>
Disk-jet connection in GRS 1915+105: X-ray soft dips as cause of radio


  We have examined the radio emission characteristics of the micro-quasar GRS
1915+105 during its X-ray emission states as classified by Belloni et al.
(2000). We find that the radio emission is high during the 'chi_1' and 'chi_3'
states (the radio ``plateau'' state) and also during the 'beta' and 'theta'
states when X-ray soft dips are present in the X-ray light curve. For all the
other X-ray states we find that the radio emission is low (< 20 mJy at 2.25
GHz). This result supports the suggestion made by Naik et al. (2000) that the
radio flares are caused by a series of X-ray dip events. To further confirm
this result, we have made a systematic study of all the PCA RXTE observations
for those days when a radio flare was present. We find 11 such observations and
find that all of them are of class 'beta', 'theta' or 'chi'. Further, we have
classified all the RXTE PCA observations obtained from 1996 November to 2000
February (when the radio data is available) and confirm that the radio flux, on
an average, is much higher during the states 'beta', 'theta' and 'chi'. Based
on these results, we argue that the radio flares are caused by the X-ray dips
in the source.

</DOC>
<DOC>
<DOCNO> 9546 </DOCNO>
Heavy-Fermions in LiV2O4: Kondo-Compensation vs. Spin-Liquid Behavior?


  7Li NMR measurements were performed in the metallic spinel LiV2O4. The
temperature dependencies of the line width, the Knight shift and the
spin-lattice relaxation rate were investigated in the temperature range 30 mK <
T < 280 K. For temperatures T < 1 K we observe a spin-lattice relaxation rate
which slows down exponentially. The NMR results can be explained by a
spin-liquid behavior and the opening of a spin gap of the order 0.6 K.

</DOC>
<DOC>
<DOCNO> 10006 </DOCNO>
Proximity Effect in Bulk LaBa_2Cu_3O_{7-y} Samples with Ag Additions


  Bulk LaBa_2Cu_3O_(7-y) samples with different Ag additions were investigated.
It was shown that Ag does not enter the crystallographic structure of the
superconductor and segregates on the grain boundary region. Current path in
these samples occurs through the proximity connected grains and this was
confirmed from the temperature dependence of the critical current density and
mutual inductance. By using the theory developed for the thin film structures
we conclude that growing of the Ag content increased the effective cross
section and the normal metal thickness. The first one prevails at low
concentration increasing the current. The second dominates at higher
concentration leading to saturation or even lowering of the critical current.

</DOC>
<DOC>
<DOCNO> 102241 </DOCNO>
Degenerate Dynamical Systems


  Dynamical systems whose symplectic structure degenerates, becoming
noninvertible at some points along the orbits are analyzed. It is shown that
for systems with a finite number of degrees of freedom, like in classical
mechanics, the degeneracy occurs on domain walls that divide phase space into
nonoverlapping regions each one describing a nondegenerate system, causally
disconnected from each other. These surfaces are characterized by the sign of
the Liouville's flux density on them, behaving as sources or sinks of orbits.
In this latter case, once the system reaches the domain wall, it acquires a new
gauge invariance and one degree of freedom is dynamically frozen, while the
remaining degrees of freedom evolve regularly thereafter.

</DOC>
<DOC>
<DOCNO> 10651 </DOCNO>
Effective Interactions and Volume Energies in Charged Colloids: Linear


  Interparticle interactions in charge-stabilized colloidal suspensions, of
arbitrary salt concentration, are described at the level of effective
interactions in an equivalent one-component system. Integrating out from the
partition function the degrees of freedom of all microions, and assuming linear
response to the macroion charges, general expressions are obtained for both an
effective electrostatic pair interaction and an associated microion volume
energy. For macroions with hard-sphere cores, the effective interaction is of
the DLVO screened-Coulomb form, but with a modified screening constant that
incorporates excluded volume effects. The volume energy -- a natural
consequence of the one-component reduction -- contributes to the total free
energy and can significantly influence thermodynamic properties in the limit of
low-salt concentration. As illustrations, the osmotic pressure and bulk modulus
are computed and compared with recent experimental measurements for deionized
suspensions. For macroions of sufficient charge and concentration, it is shown
that the counterions can act to soften or destabilize colloidal crystals.

</DOC>
<DOC>
<DOCNO> 67787 </DOCNO>
Out-of-equilibrium dynamics of large-N \phi^4 QFT in finite volume


  The $\lambda \phi^4$ model in a finite volume is studied in the infinite $N$
limit both at equilibrium and out of equilibrium, with particular attention to
certain fundamental features of the broken symmetry phase. The numerical
solution of the dynamical evolution equations shows that the zero-mode quantum
fluctuations cannot grow macroscopically large starting from microscopic
initial conditions. Thus we conclude that there is no evidence for a dynamical
Bose-Einstein condensation, in the usual sense. On the other hand, out of
equilibrium the long-wavelength fluctuations do scale with the linear size of
the system, signalling dynamical infrared properties quite different from the
equilibrium ones characteristic of the same approximation scheme.

</DOC>
<DOC>
<DOCNO> 178612 </DOCNO>
Relativistic eikonal approximation in high-energy A(e,e'p) reactions


  A fully relativistic model for the description of exclusive (e,e'p) reactions
off nuclear targets at high energies and momentum transfers is outlined. It is
based on the eikonal approximation for the ejectile scattering wave function
and a relativistic mean-field approximation to the Walecka model. Results for
^{12}C(e,e'p) and ^{16}O(e,e'p) differential cross sections and separated
structure functions are presented for four-momenta in the range 0.8 \leq Q^{2}
\leq 20 (GeV/c)^{2}. The regions of applicability of the eikonal approximation
are studied and observed to be confined to proton knockout in a relatively
small cone about the momentum transfer. A simple criterium defining the
boundaries of this cone is determined. The Q^2 dependence of the effect of
off-shell ambiguities on the different (e,e'p) structure functions is
addressed. At sufficiently high values of Q^2 their impact on the cross
sections is illustrated to become practically negligible. It is pointed out
that for the whole range of Q^2 values studied here, the bulk of the
relativistic effects arising from the coupling between the lower components in
the wave functions, is manifesting itself in the longitudinal-transverse
interference term.

</DOC>
<DOC>
<DOCNO> 69277 </DOCNO>
Coherent scattering of high-energy photon in a medium


  The coherent scattering of photon in the Coulomb field (the Delbr\"uck
scattering) is considered for the momentum transfer $\Delta \ll m$ in the frame
of the quasiclassical operator method. In high-energy region this process
occurs over rather long distance. The process amplitude is calculated taking
into account the multiple scattering of particles of the intermediate
electron-positron pair in a medium. The result is the suppression of the
process. Limiting cases of weak and strong effects of the multiple scattering
are analyzed. The approach used is the generalization of the method developed
by authors for consideration of the Landau-Pomeranchuk-Migdal effect.

</DOC>
<DOC>
<DOCNO> 169566 </DOCNO>
Incompatibility of the de Broglie-Bohm Theory with Quantum Mechanics


  It is shown that although the de Broglie-Bohm quantum theory of motion is
equivalent to standard quantum mechanics when averages of dynamical v ariables
are taken over a Gibbs ensemble of Bohmian trajectories, the equivalenc e
breaks down for ensembles built over clearly separated short intervals of time
in special multi-particle systems. This feature is exploited to propose a reali
stic experiment to distinguish between the two theories.

</DOC>
<DOC>
<DOCNO> 118790 </DOCNO>
What's wrong with AGN models for the X-ray background ?


  The origin of the hard X-ray background (XRB) as a superposition of
unabsorbed and absorbed Active Galactic Nuclei is now widely accepted as the
standard model. The identification of faint X-ray sources in ROSAT, ASCA, and
BeppoSAX medium-deep surveys and their average spectral properties are in broad
agreement with the model predictions. However, AGN models, at least in their
simplified version, seem to be at odds with some of the most recent findings
calling for substantial revisions. I will review the recent XRB "best fit"
models and discuss how the foreseen XMM and Chandra surveys will be able to
constrain the allowed parameter space.

</DOC>
<DOC>
<DOCNO> 116882 </DOCNO>
The New Gas Stripper and Charge State Separator of the Gsi High Current


  The GSI Unilac was upgraded as a high current injector for the SIS in 1999.
Therefore, the stripping section [1] at 1.4 MeV/u, where a beam transport under
highest space charge conditions and multi beam operation had to be established,
was completely new designed. Results of the commissioning of the stripper
section will be presented. The beam transport to the new gas stripper, and the
charge state analysis under space charge conditions confirmed the calculations.
A 238U4+ beam - coming from a MEVVA ion source and accelerated by the new
injector linac- was stripped (with the expected stripping efficiency) to the
charge state 28+ and successfully separated by the new spectrometer (15 degree
and 30 degree kicker magnets). The transport and matching to the poststripper
accelerator under highest space charge conditions was investigated with a 15
emA 40Ar10+ beam. Especially space charge and charge state dependent emittance
growth effects in 6d-phase space will be discussed.

</DOC>
<DOC>
<DOCNO> 121432 </DOCNO>
Implications of the Optical Observations of Neutron Stars


  We show that observations of pulsars with pulsed optical emission indicate
that the peak flux scales according to the magnetic field strength at the light
cylinder. The derived relationships indicate that the emission mechanism is
common across all of the observed pulsars with periods ranging from 33ms to 385
ms and ages of 1000-300,000 years. It is noted that similar trends exist for
$\gamma$ ray pulsars. Furthermore the model proposed by Pacini (1971) and
developed by Pacini and Salvati (1983,1987) still has validity and gives an
adequate explanation of the optical phenomena.

</DOC>
<DOC>
<DOCNO> 70132 </DOCNO>
Single Sbottom/Scharm Production at HERA in an R-Parity Breaking


  We investigate the production process of the single scalar bottom quark
(sbottom) and scalar charm quark (scharm) at HERA. The sbottom and scharm could
be produced via an R-parity breaking interactions $\lambda'_{123} \neq 0$ in
the Minimal Supersymmetric Standard Model (MSSM). These processes give a slight
excess in the invariant mass $M_{eq}$ distribution of the high $Q^2$ deep
inelastic scattering for sufficiently heavy gauginos and the scalar top (stop).
For the light gauginos and stop, it is shown that the tagging of $b/c$-quarks
and charged leptons with high transverse energies will be indispensable to
search for the processes.

</DOC>
<DOC>
<DOCNO> 83297 </DOCNO>
Using Learning-based Filters to Detect Rule-based Filtering Obsolescence


  For years, Caisse des Depots et Consignations has produced information
filtering applications. To be operational, these applications require high
filtering performances which are achieved by using rule-based filters. With
this technique, an administrator has to tune a set of rules for each topic.
However, filters become obsolescent over time. The decrease of their
performances is due to diachronic polysemy of terms that involves a loss of
precision and to diachronic polymorphism of concepts that involves a loss of
recall.
  To help the administrator to maintain his filters, we have developed a method
which automatically detects filtering obsolescence. It consists in making a
learning-based control filter using a set of documents which have already been
categorised as relevant or not relevant by the rule-based filter. The idea is
to supervise this filter by processing a differential comparison of its
outcomes with those of the control one.
  This method has many advantages. It is simple to implement since the training
set used by the learning is supplied by the rule-based filter. Thus, both the
making and the use of the control filter are fully automatic. With automatic
detection of obsolescence, learning-based filtering finds a rich application
which offers interesting prospects.

</DOC>
<DOC>
<DOCNO> 100746 </DOCNO>
On the maximal ionization of atoms in strong magnetic fields


  We give upper bounds for the number of spin 1/2 particles that can be bound
to a nucleus of charge Z in the presence of a magnetic field B, including the
spin-field coupling. We use Lieb's strategy, which is known to yield N_c<2Z+1
for magnetic fields that go to zero at infinity, ignoring the spin-field
interaction. For particles with fermionic statistics in a homogeneous magnetic
field our upper bound has an additional term of order
$Z\times\min{(B/Z^3)^{2/5},1+|\ln(B/Z^3)|^2}$.

</DOC>
<DOC>
<DOCNO> 11277 </DOCNO>
Anomalous magnetic moment of muon in 3-3-1 models


  A contribution from new gauge bosons in the ${SU}(3)_C\otimes {SU}(3)_L
\otimes {U}(1)_N$ (3 - 3 - 1) models to the anomalous magnetic moments of the
muon is calculated and numerically estimated. In the minimal 3 - 3 - 1 model, a
lower bound on the bilepton mass at a value of 167 GeV is derived. For an
expected precision($\sim 4\times 10^{-10}$) of the BNL measurements the
possible lower bounds on masses of the bileptons in the minimal version and in
the version with right-handed neutrinos are around 940 GeV and 250 GeV,
respectively.

</DOC>
<DOC>
<DOCNO> 169992 </DOCNO>
Operations, Disturbance, and Simultaneous Measurability


  Quantum mechanics predicts the joint probability distributions of the
outcomes of simultaneous measurements of commuting observables, but the current
formulation lacks the operational definition of simultaneous measurements. In
order to provide foundations of joint statistics of local general measurements
on entangled systems in a general theoretical framework, the question is
answered as to under what condition the outputs of two measuring apparatuses
satisfy the joint probability formula for simultaneous measurements of their
observables. For this purpose, all the possible state changes caused by
measurements of an observable are characterized and the notion of disturbance
in measurement is formalized in terms of operations derived by the measuring
interaction.

</DOC>
<DOC>
<DOCNO> 69172 </DOCNO>
Effect of changes in meson properties in a nuclear medium - $J/\Psi$


  We discuss the effect of changes in meson properties in a nuclear medium on
physical observables, notably, $J/\Psi$ dissociation on pion and $\rho$ meson
comovers in relativistic heavy ion collisions, and the prediction of the
$\omega$-, $\eta$- and $\eta'$-nuclear bound states.

</DOC>
<DOC>
<DOCNO> 10023 </DOCNO>
Observation of Supershell Structure in Alkali Metal Nanowires


  Nanowires are formed by indenting and subsequently retracting two pieces of
sodium metal. Their cross-section gradually reduces upon retraction and the
diameters can be obtained from the conductance. In previous work we have
demonstrated that when one constructs a histogram of diameters from large
numbers of indentation-retraction cycles, such histograms show a periodic
pattern of stable nanowire diameters due to shell structure in the conductance
modes. Here, we report the observation of a modulation of this periodic
pattern, in agreement with predictions of a supershell structure.

</DOC>
<DOC>
<DOCNO> 150805 </DOCNO>
Superextension n=(2,2) of the complex Liouville equation and its


  It is shown that the method of the nonlinear realization of local
supersymmetry previously developed in framework of supergravity being applied
to the n=(2,2) superconformal symmetry allows one to get the new form of the
exactly solvable n=(2,2) super-Liouville equation. The general advantage of
this version as compared with the conventional one is that its bosonic part
includes the complex Liouville equation. We obtain the suitable supercovariant
constraints imposed on the corresponding superfields which provide the set of
the resulting system of component equations be the same as that in model of
N=2, D=4 Green-Schwarz superstring. The general solution of this system is
derived from the corresponding solution of the bosonic string equation.

</DOC>
<DOC>
<DOCNO> 12595 </DOCNO>
Frustrated Heisenberg antiferromagnet on a pyrochlore lattice


  We investigate quantum phase transitions for the $s=1/2$ antiferromagnetic
Heisenberg model on a pyrochlore lattice. By means of a series expansion
starting from isolated tetrahedra, the ground-state phase diagram is
determined. When the ratio of the two competing exchange couplings is varied,
the first-order (second-order) quantum phase transition occurs between the two
spin gap phases (the spin-gap and the antiferromagnetic phases). We also
discuss some properties expected for the s=1 pyrochlore spin system.

</DOC>
<DOC>
<DOCNO> 102580 </DOCNO>
Remarks on the Extended Characteristic Uncertainty Relations


  Three remarks concerning the form and the range of validity of the
state-extended characteristic uncertainty relations (URs) are presented. A more
general definition of the uncertainty matrix for pure and mixed states is
suggested. Some new URs are provided.

</DOC>
<DOC>
<DOCNO> 101392 </DOCNO>
Dynamics of the Segre varieties of a real submanifold in complex space


  Iterated Segre mappings of real analytic generic submanifolds in complex
space have been an essential tool in the study of holomorphic, formal, and CR
mappings between such manifolds. In this paper we present a theory of iterated
Segre mappings for smooth or formal submanifolds. In particular, we
characterize finite type in terms of the rank of the iterated Segre mappings.
The approach given here is new, simplifies proofs, and extends results
previously known for the real analytic case.

</DOC>
<DOC>
<DOCNO> 118472 </DOCNO>
The Galactic Exoplanet Survey Telescope: A Proposed Space-Based


  We present a conceptual design for a space based Galactic Exoplanet Survey
Telescope (GEST) which will use the gravitational microlensing technique to
detect extra solar planets with masses as low as that of Mars at all
separations >~ 1 AU. The microlensing data would be collected by a diffraction
limited, wide field imaging telescope of ~ 1.5m aperture equipped with a large
array of red-optimized CCD detectors. Such a system would be able to monitor
$\sim 2\times 10^8$ stars in $\sim 6$ square degrees of the Galactic bulge at
intervals of 20-30 minutes, and it would observe $\sim 12000$ microlensing
events in three bulge seasons. If planetary systems like our own are common,
GEST should be able to detect $\sim 5000$ planets over a 2.5 year lifetime. If
gas giants like Jupiter and Saturn are rare, then GEST would detect $\sim 1300$
planets in a 2.5 year mission if we assume that most planetary systems are
dominated by planets of about Neptune's' mass. Such a mission would also
discover $\sim 100$ planets of an Earth mass or smaller if such planets are
common. This is a factor of $\sim 50$ better than the most ambitious ground
based programs that have been proposed. GEST will also be sensitive to planets
which have been separated from their parent stars.

</DOC>
<DOC>
<DOCNO> 120132 </DOCNO>
The Sloan Digital Sky Survey: Technical Summary


  The Sloan Digital Sky Survey (SDSS) will provide the data to support detailed
investigations of the distribution of luminous and non- luminous matter in the
Universe: a photometrically and astrometrically calibrated digital imaging
survey of pi steradians above about Galactic latitude 30 degrees in five broad
optical bands to a depth of g' about 23 magnitudes, and a spectroscopic survey
of the approximately one million brightest galaxies and 10^5 brightest quasars
found in the photometric object catalog produced by the imaging survey. This
paper summarizes the observational parameters and data products of the SDSS,
and serves as an introduction to extensive technical on-line documentation.

</DOC>
<DOC>
<DOCNO> 152170 </DOCNO>
Bloch-Nordsieck Approximation in Linearized Quantum Gravity


  The aim of this article is to review Fradkin's contribution in the realm of
eikonal physics. In particular, the so-called Fradkin representation is
employed to investigate a certain subclass of Feynman diagrams resulting in an
expression for the scattering amplitude at Planckian energies. The 't Hooft
poles are reproduced.

</DOC>
<DOC>
<DOCNO> 67636 </DOCNO>
A four-neutrino texture implying bimaximal flavor mixing and reduced


  A four-neutrino effective texture is described, where a sterile neutrino
mixes nearly maximally with the electron neutrino and so, is responsible for
the deficit of solar $\nu_e $'s (according to the large-angle MSW solution or
vacuum solution, of which the former is selected a posteriori). But, while
maximal mixing of muon neutrino with tauon neutrino causes the deficit of
atmospheric $\nu_\mu $'s, the original magnitude of LSND effect is reduced by
as much as four orders, becoming unobservable.

</DOC>
<DOC>
<DOCNO> 11312 </DOCNO>
Band offsets and stability of BeTe/ZnSe (100) heterojunctions


  We present ab-initio studies of band offsets, formation energy, and stability
of (100) heterojunctions between (Zn,Be)(Se,Te) zincblende compounds, and in
particular of the lattice-matched BeTe/ZnSe interface. Equal band offsets are
found at Be/Se and Zn/Te abrupt interfaces, as well as at mixed interfaces, in
agreement with the established understanding of band offsets at isovalent
heterojunctions. Thermodynamical arguments suggest that islands of non-nominal
composition may form at the interface, causing offset variations over about 0.8
eV depending on growth conditions. Our findings reconcile recent experiments on
BeTe/ZnSe with the accepted theoretical description.

</DOC>
<DOC>
<DOCNO> 102645 </DOCNO>
Some remarks on Uq(sl(2,R)) at root of unity


  We discuss a modification of Uq(sl(2,R)) and a class of its irreducible
representations when q is a root of unity.

</DOC>
<DOC>
<DOCNO> 68754 </DOCNO>
Hadron Multiplicities


  We review results on hadron multiplicities in high energy particle
collisions. Both theory and experiment are discussed. The general procedures
used to describe particle multiplicity in Quantum Chromodynamics (QCD) are
summarized. The QCD equations for the generating functions of the multiplicity
distributions are presented both for fixed and running coupling strengths. The
mean multiplicities of gluon and quark jets, their ratio, higher moments, and
the slopes of multiplicities as a function of energy scale, are among the main
global features of multiplicity for which QCD results exist. Recent data from
high energy e+e- experiments, including results for separated quark and gluon
jets, allow rather direct tests of these results. The theoretical predictions
are generally quite successful when confronted with data. Jet and subjet
multiplicities are described. Multiplicity in limited regions of phase space is
discussed in the context of intermittency and fractality. The problem of
singularities in the generating functions is formulated. Some special features
of average multiplicities in heavy quark jets are described.

</DOC>
<DOC>
<DOCNO> 80601 </DOCNO>
General Algorithm For Improved Lattice Actions on Parallel Computing


  Quantum field theories underlie all of our understanding of the fundamental
forces of nature. The are relatively few first principles approaches to the
study of quantum field theories [such as quantum chromodynamics (QCD) relevant
to the strong interaction] away from the perturbative (i.e., weak-coupling)
regime. Currently the most common method is the use of Monte Carlo methods on a
hypercubic space-time lattice. These methods consume enormous computing power
for large lattices and it is essential that increasingly efficient algorithms
be developed to perform standard tasks in these lattice calculations. Here we
present a general algorithm for QCD that allows one to put any planar improved
gluonic lattice action onto a parallel computing architecture. High performance
masks for specific actions (including non-planar actions) are also presented.
These algorithms have been successfully employed by us in a variety of lattice
QCD calculations using improved lattice actions on a 128 node Thinking Machines
CM-5.
  {\underline{Keywords}}: quantum field theory; quantum chromodynamics;
improved actions; parallel computing algorithms.

</DOC>
<DOC>
<DOCNO> 150390 </DOCNO>
Quantization of the space-time based on a formless finite fundamental


  The concept of the space (space-time) of the formless finite fundamental
elements (FFFE) is suggested. This space can be defined as a set of coverings
of the continual space by non-overlapping simply connected regions of any form
and arbitrary sizes with some probability measure. The average sizes of each
fundamental element are equal to the fundamental length. This definition
enables to describe correctly the passage from the space of the formless finite
fundamental elements to the continual space in the limit of zero value of the
fundamental length. FFFE space-time functional integral construction is
suggested. A wave function of a separate FFFE and the overall wave function of
a manifold are introduced. It is shown that many other constructions of the
discrete space-time (the Regge coverings, the lattice space-time etc.) are the
special cases of this space-time. A vacuum action problem is analyzed. One term
of this action is proportional to the volume of a fundamental element. It is
possible to direct the way for this term to yield the Nambu-Goto action in
consideration the string as one-dimensional excitation of a number of FFFEs.
Fermionic and bosonic fields in the space-time of FFFEs are excited states of
elements. Space-time supersymmetry leads to supposition that the maximal
possible number of fermionic excitations at one FFFE is equal to the number of
elements in all space-time. The compactification in this space-time means the
condition of the neighbour elements absence in compactificated dimensions.

</DOC>
<DOC>
<DOCNO> 72202 </DOCNO>
Baryon and strangeness enhancement at SPS, RHIC and LHC energies in the


  Strangeness and baryon enhancement in heavy ion collisions are discussed in
the framework of the String Fusion Model. The Monte Carlo version of this model
is shown to reasonably reproduce three of the features that have been pointed
out as evidences of the finding of the Quark Gluon Plasma. Namely
hyperon/antihyperon enhancement, dependence of the slope of the $p_{T}$
distributions on the mass of the produced particles and on the centrality of
the collision, are described. Predictions for RHIC and LHC energies are
presented.

</DOC>
<DOC>
<DOCNO> 11103 </DOCNO>
The nature of ergodicity breaking in Ising spin glasses as revealed by


  In this work we address the nature of broken ergodicity in the low
temperature phase of Ising spin glasses by examining spectral properties of
spin correlation functions $C_{ij}\equiv< S_i S_j>$. We argue that more than
one extensive (i.e., O(N)) eigenvalue in this matrix signals replica symmetry
breaking. Monte-Carlo simulations of the infinite-range Ising spin-glass model,
above and below the Almeida-Thouless line, support this conclusion. Exchange
Monte-Carlo simulations for the short-range model in four dimensions find a
single extensive eigenvalue and a large subdominant eigenvalue consistent with
droplet model expectations.

</DOC>
<DOC>
<DOCNO> 39925 </DOCNO>
Results from the CRESST Dark Matter Search at Gran Sasso


  We present the current status of CRESST(Cryogenic Rare Event Search using
Superconducting Thermometers) project and new results concerning the
development of new detectors based on the simultaneous measurement of phonons
and scintillation light. A significant reduction in the background rate could
recently be achieved. With our newly developed method for the simultaneous
measurement of scintillation light, strong background discrimination is
possible also in larger detectors, resulting in a substantial increase in WIMP
detection sensitivity.

</DOC>
<DOC>
<DOCNO> 170064 </DOCNO>
Quantum key distribution using different-frequency photons


  In this paper, we present a scheme for quantum key distribution, in which
different-frequency photons are used to encode the key. Thses
different-frequency photons are produced by an acoustic-optical modulator and
two kinds of narrow filters . This scheme may be implementable in practice.

</DOC>
<DOC>
<DOCNO> 68335 </DOCNO>
Determination of equation of state of quark matter from $J/\psi$ and


  The long life-time of the quark-gluon plasma likely to be created in the
relativistic heavy ion collisions at RHIC and LHC energies renders it sensitive
to the details of the equation of state of the quark-matter. We show that the
$p_T$ dependence of the survival probability of the directly produced $J/\psi$
at RHIC energies and that of the directly produced $\Upsilon$ at LHC energies
is quite sensitive to the speed of sound in the quark matter, which relates the
pressure and the energy density of the plasma. The transverse expansion of the
plasma is shown to strongly affect the $J/\psi$ suppression at LHC energies.

</DOC>
<DOC>
<DOCNO> 10617 </DOCNO>
Final Generalization of the Three Coupled Oscillator Model in the


  In this paper we generalize the quantum mechanical model of three coupled
oscillators because of its usage in the crystal optical activity. Using this
model we can include the influence of all essential couplings between single
oscillators which represent the molecules or atoms of optically active crystals
belonging for example to the space groups of symmetry D(3,4) or D(3,6). The
single oscillators are damped and therefore we can include both parts of the
optical activity - optical rotatory dispersion and circular dichroism - into
computations. We present more universal formulas for description of the above
mentioned parts.

</DOC>
<DOC>
<DOCNO> 8439 </DOCNO>
A reconstruction from small-angle neutron scattering measurements of the


  We have measured the diffracted neutron scattering intensities from the
square magnetic flux lattice in the perovskite superconductor Sr$_2$RuO$_4$,
which is thought to exhibit p-wave pairing with a two-component order
parameter. The relative intensities of different Bragg reflections over a wide
range of field and temperature have been shown to be inconsistent with a single
component Ginzburg-Landau theory but qualitatively agree with a two component
p-wave Ginzburg-Landau theory.

</DOC>
<DOC>
<DOCNO> 170559 </DOCNO>
Entanglement vs. Noncommutativity in Teleportation


  We provide an alternative simple proof of the necessity of entanglement in
quantum teleportation by using the no-disentanglement theorem. We show that
this is true even when the state to be teleported is known to be among two
noncommuting qubits. We further show that to teleport any set of commuting
qubits, it is sufficient to have a classically correlated channel. Using this
result we provide a simple proof of the fact that any set of bipartite
entangled states can be exactly disentangled if the single particle density
matrices of any one party commute.

</DOC>
<DOC>
<DOCNO> 71879 </DOCNO>
TAUOLA the library for tau lepton decay, and KKMC/KORALB/KORALZ/...


  The status of the Monte Carlo programs for the simulation of the $\tau$
lepton production in high energy accelerator experiments and decay is reviewed.
In particular, the status of the following packages is discussed: (i) TAUOLA
for tau-lepton decay, (ii) PHOTOS for radiative corrections in decays, (iii)
KORALB, KORALZ, KKMC packages for tau-pair production in e+e- collisions and
(iv) universal interface of TAUOLA for the decay of tau-leptons produced
by``any'' generator. Special emphasis on requirements from new and future
experiments is given. Some considerations about the software organization
necessary to keep simultaneously distinct physics initializations for TAUOLA
are also included.

</DOC>
<DOC>
<DOCNO> 119126 </DOCNO>
Supernova type Ia luminosities, their dependence on second parameters,


  A sample of 35 SNe Ia with good to excellent photometry in B and V, minimum
internal absorption, and 1200 < v < \approx 30000 km/s is compiled from the
literature. As far as their spectra are known they are all Branch-normal. For
29 of the SNe Ia also peak magnitudes in I are known. The SNe Ia have uniform
colors at maximum, i.e. <B-V>=-0.012 mag (sigma=0.051) and <V-I>=-0.276 mag
(sigma=0.078). In the Hubble diagram they define a Hubble line with a scatter
of $\sigma_M$=0.21-0.16 mag, decreasing with wavelength. The scatter is further
reduced if the SNe Ia are corrected for differences in decline rate Delta_m_15
or color (B-V). A combined correction reduces the scatter to sigma<=0.13 mag.
After the correction no significant dependence remains on Hubble type or
galactocentric distance. The Hubble line suggests some curvature which can be
differently interpreted. A consistent solution is obtained for a cosmological
model with Omega_M=0.3, Omega_Lambda=0.7, which is indicated also by much more
distant SNe Ia. Absolute magnitudes are available for eight equally blue
(Branch-normal) SNe Ia in spirals, whose Cepheid distances are known. If their
well defined mean values of M_B, M_V, and M_I are used to fit the Hubble line
to the above sample of SNe Ia one obtains H_0=58.3 km/s/Mpc, or, after
adjusting all SNe Ia to the average values of Delta_m_15 and (B-V), H_0=60.9
km/s/Mpc. Various systematic errors are discussed whose elimination tends to
decrease H_0. The finally adopted value at the 90-percent level, including
random and systematic errors, is H_0=58.5 +/- 6.3 km/s/Mpc. Several higher
values of H_0 from SNe Ia, as suggested in the literature, are found to depend
on large corrections for variations of the light curve parameter and/or on an
unwarranted reduction of the Cepheid distances of the calibrating SNe Ia.

</DOC>
<DOC>
<DOCNO> 84423 </DOCNO>
Entropy bound for a rotating system from Anti de Sitter black holes


  General geodesic equations of the motion of spinning systems around the
(3+1)-dimensional and (2+1)-dimensional rotating anti-de Sitter black holes
have been obtained. Based upon these equations, we derived the entropy bound
for a rotating system from Kerr-Anti de Sitter black holes and BTZ black holes,
respectively. Our result coincides with that of Hod's derived from Kerr black
hole, which shows that the entropy bound of the rotating system is neither
dependent on the black hole parameters, nor on spacetime dimensions. It is a
universal entropy bound.

</DOC>
<DOC>
<DOCNO> 121222 </DOCNO>
Kinematic Asymmetries in a Broad Galaxy Sample


  We analyze asymmetries in the gas rotation curves of 113 galaxies drawn from
the Nearby Field Galaxy Survey, spanning a broad range of luminosities and
morphologies. If the origin of the rotation curve is chosen to minimize the
asymmetry, then ~23% of sample galaxies show asymmetry >5% within 1.3r_e.
However, not all gas kinematic asymmetries indicate asymmetries in the
underlying potential.

</DOC>
<DOC>
<DOCNO> 118641 </DOCNO>
Recent Progress in Neutron Star Theory


  This review contains chapters discussing: Energy density fluctionals of
nuclear matter, Many-body theory of nucleon matter, Hadronic and quark matter,
Mixtures of phases in dense matter, Neutron star observations and predictions.

</DOC>
<DOC>
<DOCNO> 10636 </DOCNO>
Statistical mechanics perspective on the phase transition in vertex


  The vertex-cover problem is studied for random graphs $G_{N,cN}$ having $N$
vertices and $cN$ edges. Exact numerical results are obtained by a
branch-and-bound algorithm. It is found that a transition in the coverability
at a $c$-dependent threshold $x=x_c(c)$ appears, where $xN$ is the cardinality
of the vertex cover. This transition coincides with a sharp peak of the typical
numerical effort, which is needed to decide whether there exists a cover with
$xN$ vertices or not. For small edge concentrations $c\ll 0.5$, a cluster
expansion is performed, giving very accurate results in this regime. These
results are extended using methods developed in statistical physics. The so
called annealed approximation reproduces a rigorous bound on $x_c(c)$ which was
known previously. The main part of the paper contains an application of the
replica method. Within the replica symmetric ansatz the threshold $x_c(c)$ and
the critical backbone size $b_c(c)$ can be calculated. For $c<e/2$ the results
show an excellent agreement with the numerical findings. At average vertex
degree $2c=e$, an instability of the simple replica symmetric solution occurs.

</DOC>
<DOC>
<DOCNO> 39790 </DOCNO>
Future B Experiments from The BTeV/LHC-b Perspective


  Many measurements are necessary in the program of studying mixing, CP
violation and rare decays of b and c quarks. These measurements require large
numbers of B^o, B_s, B^- and D^{*+} hadrons. Fortunately, copius production of
particles containing b and c quarks will occur at Tevatron and the LHC. The
crucial measurements are described here, as well as the design of the two
experiments, LHC-b and BTeV, that can exploit the 4-20 x 10^{11} b hadrons
produced every 10^7 seconds.

</DOC>
<DOC>
<DOCNO> 150744 </DOCNO>
New AdS(3) x G/H compactifications of chiral IIB supergravity


  We present a new class of solutions of D=10, N=2 chiral supergravity. A
nonvanishing background for the field strength G_{MNR} of the complex two-form
triggers AdS_3 x M_7 compactifications, where M_7 is a 7-dimensional compact
manifold. When M_7 is a nonsymmetric coset space G/H, we can always find a set
of constants G_{MNR} covariantly conserved and thus satisfying the field
equations. For example the structure constants of G with indices in the G/H
directions are a covariantly conserved tensor. In some symmetric G/H, where
these structure constants vanish, there may still exist conserved 3-forms,
yielding AdS_3 x G/H solutions. The conditions for supersymmetry of the AdS_3 x
M_7 compactifications are derived, and tested for the supersymmetric solutions
AdS_3 x S^3 x T^4 and AdS_3 x S^3 x S^3 x S^1. Finally, we show that the AdS_3
x S^3 x T^4 supersymmetric background can be seen as the sigma = 0 limit in a
one-parameter class of solutions of the form AdS_3 x S^3 x CP^2, the parameter
sigma being the inverse "radius" of CP^2. For sigma different from 0 all
supersymmetries are broken.

</DOC>
<DOC>
<DOCNO> 12605 </DOCNO>
Spatially modulated magnetic structures in thin films


  The axial next-nearest neighbour Ising (ANNNI) model is studied for thin
films of up to $L= 10$ layers, with a distinct phase diagram for each film
thickness. The systematics of the ordered phases, as obtained from mean-field
theory, Monte Carlo simulations, and low temperature expansions, is discussed.
Results are compared to those for the ANNNI model in the limit $L
\longrightarrow \infty$.

</DOC>
<DOC>
<DOCNO> 11288 </DOCNO>
Ferromagnetic Film on a Superconducting Substrate


  We study the equilibrium domain structure and magnetic flux around a
ferromagnetic (FM) film with perpendicular magnetization M_0 on a
superconducting (SC) substrate. At 4{\pi}M_0<H_{c1} the SC is in the Meissner
state and the equilibrium domain width in the film, l, scales as
(l/4{\pi}{\lambda}_{L}) = (l_{N}/4{\pi}{\lambda}_{L})^{2/3} with the domain
width on a normal (non-superconducting) substrate, l_{N}/4\pi\lambda_L >> 1.
Here \lambda_L is the London penetration length. For 4{\pi}M_0 > H_{c1} and
l_{N} in excess of about 35 {\lambda}_{L}, the domains are connected by SC
vortices. We argue that pinning of vortices by magnetic domains in FM/SC
multilayers can provide high critical currents.

</DOC>
<DOC>
<DOCNO> 118692 </DOCNO>
K-Band Calibration of the Red Clump Luminosity


  The average near-infrared (K-band) luminosity of 238 Hipparcos red clump
giants is derived and then used to measure the distance to the Galactic center.
These Hipparcos red clump giants have been previously employed as I-band
standard candles. The advantage of the K-band is a decreased sensitivity to
reddening, and perhaps also a reduced systematic dependence on metallicity. In
order to investigate the latter, and also to refer our calibration to a known
metallicity zero-point, we restrict our sample of red clump calibrators to
those with abundances derived from high-resolution spectroscopic data. The mean
metallicity of the sample is [Fe/H] = -0.18 dex. The data are consistent with
no correlation between M_K and [Fe/H], and only weakly constrain the slope of
this relation. The luminosity function of the sample peaks at M_K = -1.61 +-
0.03 mag. Next, we assemble published optical and near-infrared photometry for
about 20 red clump giants in a Baade's Window field with a mean metallicity
nearly identical to that of the Hipparcos red clump. We derive the distance to
the Galactic center: R = 8.24 +- 0.42 kpc. The uncertainty in this distance
measurement is dominated by the small number of Baade's Window red clump giants
examined here [abridged].

</DOC>
<DOC>
<DOCNO> 170086 </DOCNO>
Asymptotically Good Quantum Codes


  Using algebraic geometry codes we give a polynomial construction of quantum
codes with asymptotically non-zero rate and relative distance.

</DOC>
<DOC>
<DOCNO> 151297 </DOCNO>
Noncommutative Field Theories and Smooth Commutative Limits


  We consider two model field theories on a noncommutative plane that have
smooth commutative limits. One is the single-component fermion theory with
quartic interaction that vanishes identically in the commutative limit. The
other is a scalar-fermion theory, which extends the scalar field theory with
quartic interaction by adding a fermion. We compute the bound state energies
and the two particle scattering amplitudes exactly.

</DOC>
<DOC>
<DOCNO> 152043 </DOCNO>
Comment on "First Order Transition in the Ginzburg-Landau Model"


  I present clear evidences that for $d$=2 a first order transition takes place
when the coherence length $\xi$ becomes of the order of the lattice spacing and
that this is connected with a sudden proliferation of vortices. Similar results
where reported in cond-mat/0010119 although using a different parametrization
of the G-L model which obscures the comparison with recent results obtained by
means of a variational approximation.

</DOC>
<DOC>
<DOCNO> 69348 </DOCNO>
Parametrizing and rephasing neutrino mixing


  Neutrino mixing in the standard model extensions, both renormalizable and
effective, with arbitrary numbers of the singlet and left-handed doublet
neutrinos is investigated in a systematic fashion. The charged and neutral (the
Z and Higgs mediated)lepton currents are written under general Majorana
condition, and the odservable independence of the choice of the condition, the
rephasing invariance, is studied. A parametrization of the neutrino mixing
matrices in the doublet-singlet factorized form is developed. Its relationship
with the see-saw mechanism is shown in the limit of a small doublet-singlet
mixing. The structure of the mixing matrices relevant to the neutrino
oscillation experiments is explicated.

</DOC>
<DOC>
<DOCNO> 120723 </DOCNO>
First Detection of Submillimeter [C I] Emission in the Small Magellanic


  We report the first detection of [CI] (3P1-3P0) emission at 609 um in a
region of the Small Magellanic Cloud (N27). Environments poor in heavy elements
and dust such as the SMC are thought to be dominated by photodissociation
regions. This is the lowest metallicity source where submillimeter neutral
carbon emission has been detected. Studying the [CI]/CO intensity ratio in
several sources spanning more than an order of magnitude in metallicity, Z, we
find that the [CI]/CO ratio increases for decreasing Z. The existence of such a
trend points to a photodissociation origin for most of neutral carbon in
molecular clouds, in agreement with standard PDR models. We also report ISO FIR
spectroscopic observations of N27, and use them to derive its physical
properties. Comparison between the density and radiation field revealed by FIR
diagnostics (n~300-1000 cm-3, Xuv~30-100 Xo) and those derived from millimeter
and submillimeter data (n~10^5 cm-3, Xuv<30 Xo) suggests that the FIR lines
originate in more diffuse gas, and are perhaps dominated by the interclump
medium. Regardless of the cause, analysis of the FIR and mm-submm data produces
a discrepancy of two orders of magnitude for the density of this source.

</DOC>
<DOC>
<DOCNO> 10330 </DOCNO>
On the computational capabilities of physical systems part I: the


  In this first of two papers, strong limits on the accuracy of physical
computation are established. First it is proven that there cannot be a physical
computer C to which one can pose any and all computational tasks concerning the
physical universe. Next it is proven that no physical computer C can correctly
carry out any computational task in the subset of such tasks that can be posed
to C. As a particular example, this means that there cannot be a physical
computer that can, for any physical system external to that computer, take the
specification of that external system's state as input and then correctly
predict its future state before that future state actually occurs. The results
also mean that there cannot exist an infallible, general-purpose observation
apparatus, and that there cannot be an infallible, general-purpose control
apparatus. These results do not rely on systems that are infinite, and/or
non-classical, and/or obey chaotic dynamics. They also hold even if one uses an
infinitely fast, infinitely dense computer, with computational powers greater
than that of a Turing Machine.

</DOC>
<DOC>
<DOCNO> 11163 </DOCNO>
Phase diagram of the three-dimensional Hubbard model at half filling


  We investigate the phase diagram of the three-dimensional Hubbard model at
half filling using quantum Monte Carlo (QMC) simulations. The antiferromagnetic
Neel temperature T_N is determined from the specific heat maximum in
combination with finite-size scaling of the magnetic structure factor. Our
results interpolate smoothly between the asymptotic solutions for weak and
strong coupling, respectively, in contrast to previous QMC simulations. The
location of the metal-insulator transition in the paramagnetic phase above T_N
is determined using the electronic compressibility as criterion.

</DOC>
<DOC>
<DOCNO> 9088 </DOCNO>
Is Random Close Packing of Spheres Well Defined?


  Despite its long history, there are many fundamental issues concerning random
packings of spheres that remain elusive, including a precise definition of
random close packing (RCP). We argue that the current picture of RCP cannot be
made mathematically precise and support this conclusion via a molecular
dynamics study of hard spheres using the Lubachevsky-Stillinger compression
algorithm. We suggest that this impasse can be broken by introducing the new
concept of a maximally random jammed state, which can be made precise.

</DOC>
<DOC>
<DOCNO> 13451 </DOCNO>
Nonlinear transport theory for hybrid normal-superconducting devices


  We report a theory for analyzing nonlinear DC transport properties of
mesoscopic or nanoscopic normal-superconducting (N-S) systems. Special
attention was paid such that our theory satisfies gauge invariance. At the
linear transport regime and the sub-gap region where the familiar scattering
matrix theory has been developed, we provide confirmation that our theory and
the scattering matrix theory are equivalent. At the nonlinear regime, however,
our theory allows the investigation of a number of important problems: for N-S
hybrid systems we have derived the general nonlinear current-voltage
characteristics in terms of the scattering Green's function, the second order
nonlinear conductance at the weakly nonlinear regime, and nonequilibrium charge
pile-up in the device which defines the electrochemical capacitance
coefficients.

</DOC>
<DOC>
<DOCNO> 84786 </DOCNO>
Selfgravitating nonlinear scalar fields


  We investigate the Cauchy problem for the Einstein - scalar field equations
in asymptotically flat spherically symmetric spacetimes, in the standard 1+3
formulation. We prove the local existence and uniqueness of solutions for
initial data given on a space-like hypersurface in the Sobolev $H_1\cap H_{1,4}
$ space. Solutions exist globally if a central (integral) singularity does not
form and/or outside an outgoing null hypersurface. An explicit example
demonstrates that there exists a local evolution with a naked initial curvature
singularity at the symmetry centre.

</DOC>
<DOC>
<DOCNO> 11169 </DOCNO>
Resilience of the Internet to random breakdowns


  A common property of many large networks, including the Internet, is that the
connectivity of the various nodes follows a scale-free power-law distribution,
P(k)=ck^-a. We study the stability of such networks with respect to crashes,
such as random removal of sites. Our approach, based on percolation theory,
leads to a general condition for the critical fraction of nodes, p_c, that need
to be removed before the network disintegrates. We show that for a<=3 the
transition never takes place, unless the network is finite. In the special case
of the Internet (a=2.5), we find that it is impressively robust, where p_c is
approximately 0.99.

</DOC>
<DOC>
<DOCNO> 150458 </DOCNO>
A Note on UV/IR for Noncommutative Complex Scalar Field


  Noncommutative quantum field theory of a complex scalar field is considered.
There is a two-coupling noncommutative analogue of U(1)-invariant quartic
interaction $(\phi^*\phi)^2$, namely $A\phi^*\star\phi\star\phi^*\star\phi+
B\phi^*\star\phi^*\star\phi\star\phi$. For arbitrary values of $A$ and $B$ the
model is nonrenormalizable. However, it is one-loop renormalizable in two
special cases: B=0 and $A=B$. Furthermore, in the case B=0 the model does not
suffer from IR divergencies at least at one-loop insertions level.

</DOC>
<DOC>
<DOCNO> 13332 </DOCNO>
Detection of Geometric Phases in Superconducting Nanocircuits


  When a quantum mechanical system undergoes an adiabatic cyclic evolution it
acquires a geometrical phase factor in addition to the dynamical one. This
effect has been demonstrated in a variety of microscopic systems. Advances in
nanotechnologies should enable the laws of quantum dynamics to be tested at the
macroscopic level, by providing controllable artificial two-level systems (for
example, in quantum dots and superconducting devices). Here we propose an
experimental method to detect geometric phases in a superconducting device. The
setup is a Josephson junction nanocircuit consisting of a superconducting
electron box. We discuss how interferometry based on geometrical phases may be
realized, and show how the effect may applied to the design of gates for
quantum computation.

</DOC>
<DOC>
<DOCNO> 102846 </DOCNO>
Constraint Identification and Algorithm Stabilization for Degenerate


  In the vicinity of a solution of a nonlinear programming problem at which
both strict complementarity and linear independence of the active constraints
may fail to hold, we describe a technique for distinguishing weakly active from
strongly active constraints. We show that this information can be used to
modify the sequential quadratic programming algorithm so that it exhibits
superlinear convergence to the solution under assumptions weaker than those
made in previous analyses.

</DOC>
<DOC>
<DOCNO> 85589 </DOCNO>
Precanonical Quantum Gravity: quantization without the space-time


  A nonpertubative approach to quantum gravity using precanonical field
quantization originating from the covariant De Donder-Weyl Hamiltonian
formulation which treats space and time variables on equal footing is
presented. A generally covariant ``multi-temporal'' generalized Schroedinger
equation on the finite dimensional space of metric and space-time variables is
obtained. An important ingredient of the formulation is the ``bootstrap
condition'' which introduces a classical space-time geometry as an approximate
concept emerging as the quantum average in a self-consistent with the
underlying quantum dynamics manner. An independence of the theory from an
arbitrarily fixed background is ensured in this way. The prospects and unsolved
problems of precanonical quantization of gravity are outlined.

</DOC>
<DOC>
<DOCNO> 99564 </DOCNO>
The manifold of finite rank projections in the space L(H)


  Given a complex Hilbert space H and the von Neumann algebra L(H) of all
bounded linear operators on H, we study the Grassmann manifold M of all
projections in L(H) that have a fixed finite rank r. We take the Jordan-Banach
triple theory approach which allows us to define a natural Levi-Civita
connection on M. We identify the geodesics, compute the Riemann distance and
prove some properties of M

</DOC>
<DOC>
<DOCNO> 85126 </DOCNO>
Dirac Spinor in Bianchi-I Universe with Time Dependent Gravitational and


  Self-consistent system of nonlinear spinor field and Bianchi I (BI)
gravitational one with time dependent gravitational constant ($G$) and
cosmological constant ($\Lambda$) has been studied. The initial and the
asymptotic behaviors of the field functions and the metric one have been
thoroughly investigated. Given $\Lambda = \Lambda_0/\tau^2$, with $\tau =
\sqrt{-g}$, $G$ has been estimated as a function of $\tau$. The role of perfect
fluid at the initial state of expansion and asymptotical isotropization process
of the initailly anisotropic universe has been elucidated.

</DOC>
<DOC>
<DOCNO> 10313 </DOCNO>
Magnetic-Field-Controlled Twin Boundaries Motion and Giant


  Recently, several research groups have reported on the observation of
super-large more than 5% magneto-strain effect in some non-stoichiometric
Ni-Mn-Ga alloys close to 5.78% value expected from the tetragonality aspect
ratio of the martensite crystal lattice. New Ni-Mn-Ga alloys showing giant
magneto-strain effect display simultaneously few interesting physical effects
and new behavior for some magnetic and mechanical properties which is very
different from that earlier observed in Ni-Mn-Ga showing lower magneto-strain
effect. This report represents some new experimental results and the
quantitative model describing large magneto-strain effect and main mechanical
and magnetic properties observed in several ferromagnetic shape-memory alloys.
The model application to giant magneto-strain effect recently found in some
non-stoichiometric Ni-Mn-Ga alloys is discussed.

</DOC>
<DOC>
<DOCNO> 170237 </DOCNO>
Solid State Quantum Computing Using Spectral Holes


  A quantum computer that stores information on two-state systems called
quantum bits or qubits must be able to address and manipulate individual
qubits, to effect coherent interactions between pairs of qubits, and to read
out the value of qubits.1,2 Current methods for addressing qubits are divided
up into spatial methods, as when a laser beam is focused on an individual
qubit3,4,5 or spectral methods, as when a nuclear spin in a molecule is
addressed using NMR.6,7 The density of qubits addressable spatially is limited
by the wavelength of light, and the number of qubits addressable spectrally is
limited by spin linewidths. Here, we propose a method for addressing qubits
using a method that combines spatial and spectral selectivity. The result is a
design for quantum computation that provides the potential for a density of
quantum information storage and processing many orders of magnitude greater
than that afforded by ion traps or NMR. Specifically, this method uses an
ensemble of spectrally resolved atoms in a spectral holeburning solid. The
quantum oupling is provided by strong atom-cavity interaction. Using a thin
disc of diamond containing nitrogen-vacancy color centers as an example, we
present an explicit model for realizing up to 300 coupled qubits in a single
spot. We show how about 100 operations can take place in parallel, yielding
close to 40,000 operations before decoherence.

</DOC>
<DOC>
<DOCNO> 101743 </DOCNO>
On orbit dimensions under a simultaneous Lie group action on n copies of


  We show that the maximal orbit dimension of a simultaneous Lie group action
on n copies of a manifold does not pseudo-stabilize when n increases. We also
show that if a Lie group action is (locally) effective on subsets of a
manifold, then the induced Cartesian action is locally free on an open subset
of a sufficiently big (but finite) number of copies of the manifold. The latter
is the analogue for the Cartesian action to Ovsiannikov's theorem on jet spaces
and is an important fact relative to the moving frame method and the
computation of joint invariants. Some interesting corollaries are presented.

</DOC>
<DOC>
<DOCNO> 68231 </DOCNO>
Primordial Magnetic Fields and Electroweak Baryogenesis


  In this contribution we will shortly review the main mechanism through which
primordial magnetic fields may affect the electroweak baryogenesis. It is shown
that although strong magnetic fields might enhance the strength of the
electroweak phase transition, no benefit is found for baryogenesis once the
effect of the field on the sphaleron rate is taken into account. The possible
role of hypermagnetic helicity for the electroweak baryogenesis is shortly
discussed.

</DOC>
<DOC>
<DOCNO> 118880 </DOCNO>
The First VLT FORS1 spectra of Lyman-break candidates in the HDF-S and


  We report on low-resolution multi-object spectroscopy of 30 faint targets (R
\~ 24-25) in the HDF-S and AXAF deep field obtained with the VLT Focal
Reducer/low dispersion Spectrograph (FORS1). Eight high-redshift galaxies with
2.75< z < 4 have been identified. The spectroscopic redshifts are in good
agreement with the photometric ones with a dispersion $\sigma_z = 0.07$ at z<2
and $\sigma_z = 0.16$ at z>2. The inferred star formation rates of the
individual objects are moderate, ranging from a few to a few tens solar masses
per year. Five out of the eight high-z objects do not show prominent emission
lines. One object has a spectrum typical of an AGN. In the AXAF field two
relatively close pairs of galaxies have been identified, with separations of
8.7 and 3.1 proper Mpc and mean redshifts of 3.11 and 3.93, respectively.

</DOC>
<DOC>
<DOCNO> 71251 </DOCNO>
QCD at high baryon density in a random matrix model


  A high density diquark phase seems to be a generic feature of QCD. If so it
should also be reproduced by random matrix models. We discuss a specific one in
which the random matrix elements of the Dirac operator are supplemented by a
finite chemical potential and by non-random elements which model the formation
of instanton-anti-instanton molecules. Comparing our results to those found in
a previous investigation by Vanderheyden and Jackson we find additional support
for our starting assumption, namely that the existence of a high density
diquark phase is common to all QCD-like models.

</DOC>
<DOC>
<DOCNO> 11513 </DOCNO>
Fractal Properties in Economics


  Scaling properties in financial fluctuations are reviewed from the standpoint
of statistical physics. We firstly show theoretically that the balance of
demand and supply enhances fluctuations due to the underlying phase transition
mechanism. By analyzing tick data of yen-dollar exchange rates we confirm two
fractal properties: 1 The distribution of rate change in a fixed ticks is
approximated by a symmetric stretched exponential function for a wide range of
time intervals; 2 the interval time distribution of trades nearly follows a
power law. Empirical fractal properties in companies' financial data, such as
distributions and fluctuations in assets and incomes are discussed with a
simple model. The importance of methods and theories for phase transitions is
discussed.

</DOC>
<DOC>
<DOCNO> 8273 </DOCNO>
Relationship between spiral and ferromagnetic states in the Hubbard


  We explore how the spiral spin(SP) state, a spin singlet known to accompany
fully-polarized ferromagnetic (F) states in the Hubbard model, is related with
the F state in the thermodynamic limit using the density matrix renormalization
group and exact diagonalization. We first obtain an indication that when the F
state is the ground state the SP state is also eligible as the ground state in
that limit. We then follow the general argument by Koma and Tasaki [J. Stat.
Phys. {\bf 76}, 745 (1994)] to find that: (i) The SP state possesses a kind of
order parameter. (ii) Although the SP state does not break the SU(2) symmetry
in finite systems, it does so in the thermodynamic limit by making a linear
combination with other states that are degenerate in that limit. We also
calculate the one-particle spectral function and dynamical spin and charge
susceptibilities for various 1D finite-size lattices. We find that the
excitation spectrum of the SP state and the F state is almost identical. Our
present results suggest that the SP and the F states are equivalent in the
thermodynamic limit. These properties may be exploited to determine the
magnetic phase diagram from finite-size studies.

</DOC>
<DOC>
<DOCNO> 10594 </DOCNO>
On the ground state of a completely filled lowest Landau level in two


  There exists a widely believed opinion, that the many-body ground state of a
two-dimensional electron system at a completely filled lowest Landau level (the
filling factor $\nu=1$) is described by the so-called Hartree-Fock wave
function, and that this solution is the unique, exact eigenstate of the system
at $\nu=1$. I show that this opinion is erroneous, construct an infinite number
of other variational many-body wave functions, and discuss the properties of a
few states which have the energy substantially lower than the energy of the
Hartree-Fock state.

</DOC>
<DOC>
<DOCNO> 13453 </DOCNO>
Quantum Phase Transitions and Vortex Dynamics in Superconducting


  Josephson junction arrays are ideal model systems where a variety of
phenomena, phase transitions, frustration effects, vortex dynamics, chaos, to
mention a few of them, can be studied in a controlled way. In this review we
focus on the quantum dynamical properties of low capacitance Josephson junction
arrays. The two characteristic energy scales in these systems are the Josephson
energy, associated to the tunneling of Cooper pairs between neighboring
islands, and the charging energy, which is the energy cost to add an extra
electron charge to a neutral island. The phenomena described in this review
stem from the competition between single electron effects with the Josephson
effect. One example is the (quantum) Superconductor-Insulator phase transition
which occurs by varying the ratio between the coupling constants and/or by
means of external magnetic/electric fields. We will describe how the phase
diagram depends on the various control paramters and the transport properties
close to the quantum critical point. The relevant topological excitations on
the superconducting side of the phase diagram are vortices. In low capacitance
junction arrays vortices behave as massive underdamped particles that can
exhibit quantum behaviour. We will report on the various experiments and
theoretical treatments on quantum vortex dynamics.

</DOC>
<DOC>
<DOCNO> 169608 </DOCNO>
Physical model of Schrodinger electron. Feynman convenient way in


  The physical model of a nonrelativistic quantized Schrodinger's electron (SE)
is offered. The behaviour of the SE well spread elementary electric charge had
been understood by means of two independent and different in a frequency and
size motions. The description of this resultant motion may be done by
substitution of the classical Wiener continuous integral with the quantized
Feynmam continuous integral. There are possibility to show by means of the
existent not only formal but substantial analogy between the quadratic
differential wave equation in partial derivatives of Schrodinger and quadratic
differential particle equation in partial derivatives of Hamilton-Jacoby that
the addition of a kinetic energy of the stochastic harmonic oscillation of some
quantized micro particles to the kinetic energy of classical motion of the same
micro particles formally determines their wave behaviour.It turns out the
stochastic motion of the quantized micro particles powerfully to break up the
smooth thin line of the classical motion of the same micro particle in many
broad cylindrically spread path. The SE participate in stochastically roughly
determined circumferences within different flats and with different radii, with
centres which are successively arranjed over short and very disorderly
orientated lines. Therefore the quantized motion of some micro particle cannot
be descripted by smooth thin well contured (focused) line, describing the
classical motion of the macro particle.

</DOC>
<DOC>
<DOCNO> 101508 </DOCNO>
Algebraic Poincare cobordism


  This paper is an introduction to the use of the cobordism of chain complexes
with Poincar\'e duality in surgery theory. It is a companion to the author's
paper "An introduction to algebraic surgery" math.AT/0008071 (to appear in
Volume 2 of Surveys in Surgery Theory, Ann. of Maths. Studies, Princeton, 2001)
which is an introduction to algebraic surgery using forms and formations.

</DOC>
<DOC>
<DOCNO> 68049 </DOCNO>
Convergence of the expansion of the Laplace-Borel integral in


  The optimal conformal mapping of the Borel plane was recently used to
accelerate the convergence of the perturbation expansions in QCD. In this work
we discuss the relevance of the method for the calculation of the Laplace-Borel
integral expressing formally the QCD Green functions. We define an optimal
expansion of the Laplace-Borel integral in the principal value prescription and
establish conditions under which the expansion is convergent.

</DOC>
<DOC>
<DOCNO> 170437 </DOCNO>
Quantum information distributors: Quantum network for symmetric and


  We show that for any Hilbert-space dimension, the optimal universal quantum
cloner can be constructed from essentially the same quantum circuit, i.e., we
find a universal design for universal cloners. In the case of infinite
dimensions (which includes continuous variable quantum systems) the universal
cloner reduces to an essentially classical device. More generally, we construct
a universal quantum circuit for distributing qudits in any dimension which acts
covariantly under generalized displacements and momentum kicks. The behavior of
this covariant distributor is controlled by its initial state. We show that
suitable choices for this initial state yield both universal cloners and
optimized cloners for limited alphabets of states whose states are related by
generalized phase-space displacements.

</DOC>
<DOC>
<DOCNO> 7693 </DOCNO>
Electron Transfer in Porphyrin Complexes in Different Solvents


  The electron transfer in different solvents is investigated for systems
consisting of donor, bridge and acceptor. It is assumed that vibrational
relaxation is much faster than the electron transfer. Electron transfer rates
and final populations of the acceptor state are calculated numerically and in
an approximate fashion analytically. In wide parameter regimes these solutions
are in very good agreement. The theory is applied to the electron transfer in
${\rm H_2P-ZnP-Q}$ with free-base porphyrin (${\rm H_2P}$) being the donor,
zinc porphyrin (${\rm ZnP}$) the bridge, and quinone (${\rm Q}$) the acceptor.
It is shown that the electron transfer rates can be controlled efficiently by
changing the energy of the bridging level which can be done by changing the
solvent. The effect of the solvent is determined for different models.

</DOC>
<DOC>
<DOCNO> 80968 </DOCNO>
Monopoles, vortices and confinement in SU(3) gauge theory


  We compute, in SU(3) pure gauge theory, the vacuum expectation value (vev) of
the operator which creates a $Z_3$ vortex wrapping the lattice through periodic
boundary conditions (dual Polyakov line). The technique used is the same
already tested in the SU(2) case. The dual Polyakov line proves to be a good
disorder parameter for confinement, and has a similar behaviour to the monopole
condensate. The new features which characterise the construction of the
disorder operator in SU(3) are emphasised.

</DOC>
<DOC>
<DOCNO> 102244 </DOCNO>
BRS-Chern-Simons forms and cyclic homology


  We use some BRS techniques to construct Chern-Simons forms generalizing the
Chern character of K_1 groups in the Cuntz-Quillen description of cyclic
homology.

</DOC>
<DOC>
<DOCNO> 67926 </DOCNO>
Neutrino masses, mixing and oscillations


  These are lectures given at the CERN-JINR school on high energy physics. The
possibilities of the mixing of massive Dirac and Majorana neutrinos are
discussed. The theory of neutrino oscillations in vacuum is presented. The
trasitions between differen flavor neutrinos in matter are discussed. A short
review of the results of the neutrino oscillation experiments is provided.

</DOC>
<DOC>
<DOCNO> 71575 </DOCNO>
Study of direct-photon and pion production


  We present comparisons of high-pT photon and pion production in hadronic
interactions with expectations from next-to-leading order perturbative QCD (NLO
pQCD). We also comment on phenomenological models of kT smearing (which
approximate effects of additional soft-gluon emission) and on the status of
resummation calculations.

</DOC>
<DOC>
<DOCNO> 102064 </DOCNO>
Tannakian Fundamental Groups Associated to Galois Groups


  This is a corrected and extended version of our expository paper explaining
some conjectures of Deligne and Goncharov concerning Galois actions on
fundamental groups. It takes a more tannakian point of view than our other
paper (math.AG/0006158). Related results about the weighted completion of the
arithmetic fundamental groups of moduli spaces of curves are also announced.

</DOC>
<DOC>
<DOCNO> 151086 </DOCNO>
Extreme black hole entropy obtained in an operational approach


  The entropy of anti-de Sitter Reissner-Nordstrom black hole is found to be
stored in the material which gathers to form it and equals to $A/4$ regardless
of material states. Extending the study to two kinds of extreme black holes, we
find different entropy results for the first kind of extreme black hole due to
different material states. However for the second kind of extreme black hole
the results of entropy are uniform independently of the material states.
Relations between these results and the stability of two kinds of extreme black
holes have been addressed.

</DOC>
<DOC>
<DOCNO> 12027 </DOCNO>
"Barber pole turbulence" in large aspect ratio Taylor-Couette flow


  Investigations of counter-rotating Taylor-Couette flow (TCF) in the narrow
gap limit are conducted in a very large aspect ratio apparatus. The phase
diagram is presented and compared to that obtained by Andereck et al. The
spiral turbulence regime is studied by varying both internal and external
Reynolds numbers. Spiral turbulence is shown to emerge from the fully turbulent
regime via a continuous transition appearing first as a modulated turbulent
state, which eventually relaxes locally to the laminar flow. The connection
with the intermittent regimes of the plane Couette flow (pCf) is discussed.

</DOC>
<DOC>
<DOCNO> 9796 </DOCNO>
Spin-orbit and exchange interaction in surface quantum wells on gapless


  The first study of two-dimensional electron gas in surface layers on HgMnTe
with inverted bands is carried out experimentally and theoretically. It is
shown that the structure of investigated capacitance magnetooscillations in
HgMnTe MOS structures is fully similar to the one in the non-magnetic
narrow-gap semiconductor HgCdTe and the sole effect due to exchange interaction
is the temperature shift of beat nodes. The information about exchange effects
is obtained only due to our modeling of oscillations, because any pronounced
changes in the position of oscillations are not observed and the separate spin
components are not resolved. The Landau levels are calculated in the framework
of concept we developed previously for the description of subband dispersions
in zero magnetic field B=0. The new parameters (like those of $T/\sqrt{eB}$)
arise in the theory of magnetooscillations in the semiconductors with
quasirelativistic spectrum in contrast to the case of parabolic bands. The
modeling shows that the spin-orbit splitting far exceeds a contribution due to
exchange interaction. The calculated amplitudes of ``partial'' oscillations for
different spin branches of spectrum are essentially different in accordance
with the observed difference in the intensity of corresponding lines in Fourier
spectra. The comparison between experiment and theory for different
temperatures and parameters of exchange interaction is reported. The dominant
mechanisms of the scattering responsible for the broadening of Landau levels
are discussed.

</DOC>
<DOC>
<DOCNO> 120774 </DOCNO>
Planck-scale deformation of Lorentz symmetry as a solution to the UHECR


  One of the most puzzling current experimental physics paradoxes is the
arrival on Earth of Ultra High Energy Cosmic Rays with energies above the GZK
threshold. The recent observation of 20TeV photons from Mk 501 is another
somewhat similar paradox. Several models have been proposed for the UHECR
paradox. No solution has yet been proposed for the TeV-$\gamma$ paradox.
Remarkably, the drastic assumption of a violation of ordinary Lorentz
invariance would resolve both paradoxes. We present a formalism for the
description of the type of Lorentz-invariance deformation (LID) that could be
induced by non-trivial short-distance structure of space-time, and we show that
this formalism is well suited for comparison of experimental data with LID
predictions. We use the UHECR and TeV-$\gamma$ data, as well as bounds on
time-of-flight differences between photons of different energies, to constrain
the LID parameter space. A model with only two parameters, an energy scale and
a dimensionless parameter characterizing the functional dependence on the
energy scale, is shown to be sufficient to solve both the UHECR and the
TeV-$\gamma$ threshold anomalies while satisfying the time-of-flight bounds.
The allowed region of the two-parameter space is relatively small, but,
remarkably, it fits perfectly the expectations of the quantum-gravity-motivated
space-time models known to support such deformations of Lorentz invariance:
integer value of the dimensionless parameter and characteristic energy scale
constrained to a narrow interval in the neighborhood of the Planck scale.

</DOC>
<DOC>
<DOCNO> 120894 </DOCNO>
Mira's wind explored in scattering infrared CO lines


  We have observed the intermediate regions of the circumstellar envelope of
Mira (o Ceti) in photospheric light scattered by three vibration-rotation
transitions of the fundamental band of CO, from low-excited rotational levels
of the ground vibrational state, at an angular distance of beta = 2"-7" away
from the star. The data were obtained with the Phoenix spectrometer mounted on
the 4 m Mayall telescope at Kitt Peak. The spatial resolution is approximately
0.5" and seeing limited. Our observations provide absolute fluxes, leading to
an independent new estimate of the mass-loss rate of approximately 3e-7
Msun/yr, as derived from a simple analytic wind model. We find that the
scattered intensity from the wind of Mira for 2" < beta < 7" decreases as
beta^-3, which suggests a time constant mass-loss rate, when averaged over 100
years, over the past 1200 years.

</DOC>
<DOC>
<DOCNO> 85572 </DOCNO>
Scalar, electromagnetic, and gravitational self-forces in weakly curved


  We calculate the self-force experienced by a point scalar charge, a point
electric charge, and a point mass moving in a weakly curved spacetime
characterized by a time-independent Newtonian potential. The self-forces are
calculated by first computing the retarded Green's functions for scalar,
electromagnetic, and (linearized) gravitational fields in the weakly curved
spacetime, and then evaluating an integral over the particle's past world line.
In all three cases the self-force contains both a conservative and a
nonconservative (radiation-reaction) part. The conservative part of the
self-force is directly related to the presence of matter in the spacetime. The
radiation-reaction part of the self-force, on the other hand, is insensitive to
the presence of matter. Our result for the gravitational self-force is
disturbing: a radiation-reaction force should not appear in the equations of
motion at this level of approximation, and it should certainly not give rise to
radiation antidamping. The last section of this paper attempts to make sense of
this result by placing it in the context of the post-Newtonian N-body problem.

</DOC>
<DOC>
<DOCNO> 80587 </DOCNO>
Massive chiral random matrix ensembles at beta = 1 & 4 : Finite-volume


  In a deep-infrared (ergodic) regime, QCD coupled to massive pseudoreal and
real quarks are described by chiral orthogonal and symplectic ensembles of
random matrices. Using this correspondence, general expressions for the QCD
partition functions are derived in terms of microscopically rescaled mass
variables. In limited cases, correlation functions of Dirac eigenvalues and
distributions of the smallest Dirac eigenvalue are given as ratios of these
partition functions. When all masses are degenerate, our results reproduce the
known expressions for the partition functions of zero-dimensional sigma models.

</DOC>
<DOC>
<DOCNO> 13907 </DOCNO>
Reply to Comment on "Nature of Spin Glass State"


  This is a reply to cond-mat/0010033 by Newman and Stein, which is a comment
on on our paper Phys. Rev. Lett. 85, 3017 (2000), cond-mat/0002134.

</DOC>
<DOC>
<DOCNO> 68837 </DOCNO>
Microlensing searches of dark matter


  The evolution of the observational results of microlensing towards the
 LMC and some of the suggested interpretations to account for them are
discussed. It is emphasized that the results at present are indicative of a
lensing population of white dwarfs, possibly in the spheroid (not dark halo) of
the Galaxy, together with the more standard backgrounds of stellar populations
in the Magellanic Clouds and in the
 Galaxy. This is also hinted by dynamical estimates of the spheroid mass and by
recent direct searches of old white dwarfs.

</DOC>
<DOC>
<DOCNO> 121138 </DOCNO>
Dynamics of Black-Hole Nuclei


  Space-based observations are beginning to yield detailed information about
the stellar kinematics at the very centers of galaxies, within the sphere of
gravitational influence of the black hole. The structure and dynamics of these
regions is probably determined in part by the infall and coalescence of black
holes during galaxy mergers. A goal of N-body simulations is to reproduce the
kinematics near the black holes as well as the relations that exist between the
nuclear and global properties of galaxies. However, the problem is
computationally difficult due to the wide range of length and time scales, and
no single N-body code can efficiently follow the evolution from kiloparsec to
sub-parsec scales. We review existing N-body work on this problem and present
the first, fully self-consistent merger simulations of galaxies containing
dense stellar cusps and black holes.

</DOC>
<DOC>
<DOCNO> 13945 </DOCNO>
Universal Properties in Low Dimensional Fermionic Systems and


  We analyze the universal transport behavior in 1D and 2D fermionic systems by
following the unified framework provided by bosonization. The role played by
the adiabatic transition between interacting and noninteracting regions is
emphasized.

</DOC>
<DOC>
<DOCNO> 119975 </DOCNO>
Theoretical Models for Classical Cepheids: VII. Metallicity effects on


  We use theoretical Period-Luminosity and Period-Luminosity-Color relations in
the VI passbands, as based on nonlinear, nonlocal and time-dependent convective
pulsating models, to predict the reddening and true distance modulus of distant
Cepheids observed with the Hubble Space Telescope. By relying on the pulsating
models with metal content Z=0.008, we find that the theoretical predictions
agree to the values obtained by the Extragalactic Distance Scale Key Project on
the basis of empirical Period-Luminosity relations referenced to LMC variables.
In the meantime, from the theoretical relations with Z=0.004 and 0.02 we find
that the predicted E(B-V) and mu_0 decrease as the adopted metal content
increases. This suggests a metallicity correction to LMC-based distances as
given by about -0.27 mag/dex. Such a theoretical correction appears supported
by an existing, although weak, correlation between the Cepheid distance and the
[O/H] metallicity of galaxies within a given group or cluster, as well as by a
similar correlation between the H_0 estimate and the [O/H] metallicity of the
galaxies which calibrate the SNIa luminosity. On the contrary, the metallicity
correction earlier suggested on empirical grounds seem to be excluded.
Eventually we suggest that the average value <H_0> ~ 67 km/s/Mpc provided by
the Key Project team should increase at least up to ~ 69 km/s/Mpc.

</DOC>
<DOC>
<DOCNO> 9996 </DOCNO>
Linked-Cluster Expansion of the Ising Model


  The linked-cluster expansion technique for the high-temperature expansion of
spin model is reviewed. A new algorithm for the computation of three-point and
higher Green's functions is presented. Series are computed for all components
of two-point Green's functions for a generalized 3D Ising model, to 25th order
on the bcc lattice and to 23rd order on the sc lattice. Series for
zero-momentum four-, six-, and eight-point functions are computed to 21st,
19th, and 17th order respectively on the bcc lattice.

</DOC>
<DOC>
<DOCNO> 40315 </DOCNO>
Charged Kaons at the Main Injector (CKM)


  The CKM collaboration is proposing to measure the branching ratio of the rare
K decay (K+ --> pi+ nu nubar) at the Main Injector at Fermilab. Our goal is to
be able to observe about 100 events, for a Standard Model branching ratio of
about 1.0E-10. This implies that we must be able to reduce the background to a
few events.

</DOC>
<DOC>
<DOCNO> 170528 </DOCNO>
Entanglement Measures under Symmetry


  We show how to simplify the computation of the entanglement of formation and
the relative entropy of entanglement for states, which are invariant under a
group of local symmetries. For several examples of groups we characterize the
state spaces, which are invariant under these groups. For specific examples we
calculate the entanglement measures. In particular, we derive an explicit
formula for the entanglement of formation for UU-invariant states, and we find
a counterexample to the additivity conjecture for the relative entropy of
entanglement.

</DOC>
<DOC>
<DOCNO> 99815 </DOCNO>
Interferometers and Decoherence Matrices


  It is shown that the Lorentz group is the natural language for two-beam
interferometers if there are no decoherence effects. This aspect of the
interferometer can be translated into six-parameter representations of the
Lorentz group, as in the case of polarization optics where there are two
orthogonal components of one light beam. It is shown that there are groups of
transformations which leave the coherency or density matrix invariant, and this
symmetry property is formulated within the framework of Wigner's little groups.
An additional mathematical apparatus is needed for the transition from a pure
state to an impure state. Decoherence matrices are constructed for this
process, and their properties are studied in detail. Experimental tests of this
symmetry property are possible.

</DOC>
<DOC>
<DOCNO> 14175 </DOCNO>
Current-induced conductance switching in epitaxial La0.7Sr0.3MnO3/SrTiO3


  We report on the non-linear in-plane electrical transport in coherently grown
[La0.7Sr0.3MnO3/SrTiO3] multilayers with ultrathin (< 3 nm) single layers.
Current-induced switching of the conductance, with low conductance at larger
currents, is demonstrated. The conductance switching is modified under a
magnetic field, resulting in an extremely large magnetoresistance of negative,
or in a special case even positive, sign. Our results suggest a percolative
nature of transport where a large local current density gives rise to a
spin-polarizing and a thermal effect of current.

</DOC>
<DOC>
<DOCNO> 72305 </DOCNO>
Neutralino-Nucleus Elastic Cross Section in the Minimal Supersymmetric


  We study the elastic scattering of the lightest neutralino with a nucleus in
the framework of the minimal supersymmetric standard model (MSSM) with explicit
flavor preserving CP violation, including the one-loop CP-violating neutral
Higgs-boson mixing effects induced dominantly by the CP phases in the top and
bottom (s)quark sectors. We construct the most general form of the effective
Lagrangian for the neutralino-nucleus scattering in the limit of vanishing
momentum transfers and then we perform a comprehensive analysis of the effects
of the complex CP phases on the mass spectra of the lightest neutralino,
neutral Higgs bosons and top squarks, and on the the spin-dependent and
spin-independent neutralino-nucleus scattering cross section for three neucleus
targets F, Si and Ge. The CP phases can reduce or enhance the
neutralino-nucleus cross sections significantly, depending on the values of the
real parameters in the MSSM.

</DOC>
<DOC>
<DOCNO> 121535 </DOCNO>
The template type Ia supernova 1996X


  UBVRIJ photometry and optical spectra of the Type Ia SN 1996X obtained at ESO
during a one-year-long observational campaign are presented, and supplemented
by late time HST photometry. Spectroscopically, SN 1996X appears to be a
`normal' SN Ia. The apparent magnitude at maximum was B=13.24 +/- 0.02, and the
colour B-V=0.00 +/- 0.03. The luminosity decline rate, Delta m_B(15) = 1.31 +/-
0.08, is close to average for a SN Ia. The best estimate of the galactic
extinction is A_B=0.30 +/- 0.05, and there is evidence that reddening within
the parent galaxy is negligible. Detailed comparison of the light and colour
curves of various `normal' SNe Ia shows that the assumption that multicolour
light curves can be described simply as a one-parameter family is not perfect.
Together with problems in the calibration of the templates, this may explain
the discrepancies in the distance modulus derived adopting different
calibrations of the absolute magnitude vs. light curve shape relations. Indeed
we found that M_B ranges from -19.08 to -19.48 and M-m range from 32.02 to
32.48 depending on the method used (Hamuy et al. 1996a,Phillips et al. 1999,
Riess et al. 1998a). Computations of model light curve and synthetic spectra
for both early- and late-times, confirm that 1996X is a normal Type Ia SN and
that a satisfactory fit can be obtained using a W7 progenitor structure only if
we adopt the short distance. A larger distance would imply a too large Ni mass
for this fainter than average SNIa.

</DOC>
<DOC>
<DOCNO> 40635 </DOCNO>
Heavy Quark Production at HERA


  Recent results on heavy flavor production at HERA are presented. New
measurements of charm production are available in the region of $ Q^2 <$ 1000
GeV$^2$ for $D^*$ and in the photoproduction limit, $Q^2\to 0$, for $D_s$. The
results are compared to theoretical calculations and the charm proton structure
function \f2cc$(x,Q^2)$ is extracted. A new independent measurement of the
$b\bar{b}$ cross section using a $b$-lifetime tag is reported.

</DOC>
<DOC>
<DOCNO> 151130 </DOCNO>
The inversion relation and the dilute A_{3,4,6} eigenspectrum


  On the basis of the result obtained by applying Baxter's exact perturbative
approach to the dilute A_3 model to give the E_8 mass spectrum, the dilute A_L
inversion relation was used to predict the eigenspectra in the L=4 and L=6
cases (corresponding to E_7 and E_6 respectively). In calculating the
next-to-leading term in the correlation lengths, or equivalently masses, the
inversion relation condition gives a surprisingly simple result in all three
cases, and for all masses.

</DOC>
<DOC>
<DOCNO> 116999 </DOCNO>
Efficient Design Scheme of Superconducting Cavity


  For many next-generation high intensity proton accelerator applications
including the Spallation Neutron Source (SNS), superconducting (SC) RF provides
the technology of choice for the linac. In designing the superconducting
cavity, several features, such as peak fields, inter-cell coupling, mechanical
stiffness, field flatness, external Q, manufacturability, shunt impedance,
higher order mode (HOM), etc., should be considered together. A systematic
approach to determine the optimum cavity shape by exploring the entire
geometric space of the cavity has been found. The most efficient use of RF
energy can be accomplished by adjusting the cell shape. A small region in
parameter space satisfying all reasonable design criteria has been found. With
this design procedure, choosing the optimum shape is simplified. In this paper,
the whole design procedure of this optimisation scheme is explained and applied
to the SNS cavity design.

</DOC>
<DOC>
<DOCNO> 71450 </DOCNO>
Three-Neutrino Analysis of the Super-Kamiokande Solar Neutrino Data


  Withdrawn by the authors due to crucial errors in equations (1) and (2).

</DOC>
<DOC>
<DOCNO> 11955 </DOCNO>
Linear to quadratic crossover of Cooper pair dispersion relation


  Cooper pairing is studied in three dimensions to determine its binding energy
for all coupling using a general separable interfermion interaction. Also
considered are Cooper pairs (CPs) with nonzero center-of-mass momentum (CMM). A
coupling-independent {\it linear} term in the CMM dominates the pair excitation
energy in weak coupling and/or high fermion density, while the more familiar
quadratic term prevails only in the extreme low-density (i.e., vacuum) limit
for any nonzero coupling. The linear-to-quadratic crossover of the CP
dispersion relation is analyzed numerically, and is expected to play a central
role in a model of superconductivity (and superfluidity) simultaneously
accommodating a BCS condensate as well as a Bose-Einstein condensate of CP
bosons.

</DOC>
<DOC>
<DOCNO> 120689 </DOCNO>
Further daemon detection experiments


  The experiments on detection of daemons captured into geocentric orbits,
which are based on the postulated fast decay of daemon-containing nuclei, have
been continued. By properly varying the experimental parameters, it has become
possible to reveal and formulate some relations governing the interaction of
daemons with matter. Among them are, for instance, the emission of energetic
Auger-type electrons in the capture of an atomic nucleus, the possibility of
charge exchange involving the capture of a heavier nucleus etc. The decay time
of a daemon-containing proton has been measured to be D \tau ~ approx 2 mks.
The daemon flux at the Earth's surface is f ~ 10^{-7} cm^-2 s^-1. One should
point out, on the one hand, the reproducibility of the main results, and on the
other, the desirability of building up larger statistics and employing more
sophisticated experimental methods to reveal finer details in the daemon
interaction with matter.

</DOC>
<DOC>
<DOCNO> 102229 </DOCNO>
More about vanishing cycles and mutation


  The paper continues the discussion of symplectic aspects of Picard-Lefschetz
theory begun in "Vanishing cycles and mutation" (this archive). There we
explained how to associate to a suitable fibration over a two-dimensional disc
a triangulated category, the "derived directed Fukaya category" which describes
the structure of the vanishing cycles. The present second part serves two
purposes. Firstly, it contains various kinds of algebro-geometric examples,
including the "mirror manifold" of the projective plane. Secondly there is a
(largely conjectural) discussion of more advanced topics, such as (i)
Hochschild cohomology, (ii) relations between Picard-Lefschetz theory and Morse
theory, (iii) a proposed "dimensional reduction" algorithm for doing certain
Floer cohomology computations.

</DOC>
<DOC>
<DOCNO> 72067 </DOCNO>
Soft photon emission as a sign of sharp transition in quark-gluon plasma


  Photon emission arising in the course of transition between the states of
quark-gluon and hadron plasma has been considered. Single-photon distributions
and two-photon correlations in central rapidity region have been calculated for
heavy ion collisions at high energies. It has been found that opposite side
two-photon correlations can serve as a sign of sharp transitions between the
states of strongly interaction matter.

</DOC>
<DOC>
<DOCNO> 10574 </DOCNO>
Creep of superconducting vortices in the limit of vanishing temperature:


  We theoretically study the creep of vortex matter in superconductors. The low
temperatures experimental phenomenology, previously interpreted in terms of
``quantum tunnelling'' of vortices, is reproduced by Monte Carlo simulations of
a purely ``classical'' vortex model. We demonstrate that a non-zero creep rate
in the limit of vanishing temperature is to be expected in systems with slow
relaxations as a consequence of their off-equilibrium evolution in a complex
free energy landscape.

</DOC>
<DOC>
<DOCNO> 9406 </DOCNO>
One-dimensional nature of the magnetic fluctuations in


  There is increasing evidence that inhomogeneous distributions of charge and
spin--so-called "striped phases"--play an important role in determining the
properties of the high-temperature superconductors. For example, recent
neutron-scattering measurements on the YBa$_2$Cu$_3$O$_{7-x}$ family of
materials show both spin and charge fluctuations that are consistent with the
striped-phase picture. But the fluctuations associated with a striped phase are
expected to be one-dimensional, whereas the magnetic fluctuations observed to
date appear to display two-dimensional symmetry. We show here that this
apparent two-dimensionality results from measurements on twinned crystals, and
that similar measurements on substantially detwinned crystals of
YBa$_2$Cu$_3$O$_{6.6}$ reveal the one-dimensional character of the magnetic
fluctuations, thus greatly strengthening the striped-phase interpretation.
Moreover, our results also suggest that superconductivity originates in charge
stripes that extend along the b crystal axis, where the superfluid density is
found to be substantially larger than for the a direction.

</DOC>
<DOC>
<DOCNO> 83500 </DOCNO>
A brief overview of the MAD debugging activities


  Debugging parallel and distributed programs is a difficult activitiy due to
the multiplicity of sequential bugs, the existence of malign effects like race
conditions and deadlocks, and the huge amounts of data that have to be
processed. These problems are addressed by the Monitoring And Debugging
environment MAD, which offers debugging functionality based on a graphical
representation of a program's execution. The target applications of MAD are
parallel programs applying the standard Message-Passing Interface MPI, which is
used extensively in the high-performance computing domain. The highlights of
MAD are interactive inspection mechanisms including visualization of
distributed arrays, the possibility to graphically place breakpoints, a
mechanism for monitor overhead removal, and the evaluation of racing messages
occuring due to nondeterminism in the code.

</DOC>
<DOC>
<DOCNO> 119869 </DOCNO>
On the Integrated Spectrum of the X-ray Binaries and the Origin of Soft


  Using ROSAT PSPC data, we have performed several tests aimed at understanding
the origin of the soft X-ray spectral component detected from the bulge of M31.
We find that a significant soft component in the spectrum of the bulge is
spatially correlated with the unresolved X-ray emission near the core of M31,
which is probably a hot interstellar medium or perhaps a population of multiple
faint sources. For the first time, we extracted the spectrum of this unresolved
emission, by removing point sources dominating the integral spectrum of the
bulge, and found it to be responsible for the most of soft excess. A soft
spectral component is not at all needed to fit the point source spectrum that
remains after subtracting the unresolved emission. The integral spectra of
bright point sources, both inside and outside of the M31 bulge, can be fitted
with a single power-law in the ROSAT band. Our analysis rules out the previous
suggestion that all bulge emission in M31 may be generated by low mass X-ray
binaries (Irwin & Bregman, 1999).

</DOC>
<DOC>
<DOCNO> 9323 </DOCNO>
Damaging and Cracks in Thin Mud Layers


  We present a detailed study of a two-dimensional minimal lattice model for
the description of mud cracking in the limit of extremely thin layers. In this
model each bond of the lattice is assigned to a (quenched) breaking threshold.
Fractures proceed through the selection of the part of the material with the
smallest breaking threshold. A local damaging rule is also implemented, by
using two different types of weakening of the neighboring sites, corresponding
to different physical situations. Some analytical results are derived through a
probabilistic approach known as Run Time Statistics. In particular, we find
that the total time to break down the sample grows with the dimension $L$ of
the lattice as $L^2$ even though the percolating cluster has a non trivial
fractal dimension. Furthermore, a formula for the mean weakening in time of the
whole sample is obtained.

</DOC>
<DOC>
<DOCNO> 101687 </DOCNO>
Examples of locally compact quantum groups through the bicrossed product


  The main aim of this paper is to introduce some examples of non-compact
locally compact quantum groups to a non-specialized audience. The major
importance of these examples is their simplicity. Other examples as the quantum
E(2) group of Woronowicz are much more difficult to construct. We will make use
of the bicrossed product construction to obtain our examples. This construction
dates back to Kac, Takeuchi and Majid. It was also considered by Baaj &
Skandalis.

</DOC>
<DOC>
<DOCNO> 83302 </DOCNO>
Fuzzy data: XML may handle it


  Data modeling is one of the most difficult tasks in application engineering.
The engineer must be aware of the use cases and the required application
services and at a certain point of time he has to fix the data model which
forms the base for the application services. However, once the data model has
been fixed it is difficult to consider changing needs. This might be a problem
in specific domains, which are as dynamic as the healthcare domain. With fuzzy
data we address all those data that are difficult to organize in a single
database. In this paper we discuss a gradual and pragmatic approach that uses
the XML technology to conquer more model flexibility. XML may provide the clue
between unstructured text data and structured database solutions and shift the
paradigm from "organizing the data along a given model" towards "organizing the
data along user requirements".

</DOC>
<DOC>
<DOCNO> 12648 </DOCNO>
Low energy exciton states in a nanoscopic semiconducting ring


  We consider an effective mass model for an electron-hole pair in a simplified
confinement potential, which is applicable to both a nanoscopic self-assembled
semiconducting InAs ring and a quantum dot. The linear optical susceptibility,
proportional to the absorption intensity of near-infrared transmission, is
calculated as a function of the ring radius $% R_0$. Compared with the
properties of the quantum dot corresponding to the model with a very small
radius $R_0$, our results are in qualitative agreement with the recent
experimental measurements by Pettersson {\it et al}.

</DOC>
<DOC>
<DOCNO> 85416 </DOCNO>
Viscous cosmologies in scalar-tensor theories for Kasner type metrics


  In a viscous Bianchi type I metric of the Kasner form, it is well known that
it is not possible to describe an anisotropic physical model of the universe,
which satisfies the second law of thermodynamics and the dominant energy
condition (DEC) in Einstein's theory of gravity. We examine this problem in
scalar-tensor theories of gravity. In this theory we show that it is possible
to describe the growth of entropy, keeping the thermodynamics and the dominant
energy condition.

</DOC>
<DOC>
<DOCNO> 12486 </DOCNO>
Glass transitions of freely suspended polymer films


  We present a modified version of our "sliding model", where chain arcs,
between two contacts at the surface, may move if all the barriers along the arc
are weaker than a certain threshold.An important advance of the revised model
is that the high limiting chain lengths N* observed in the experiments are
naturally accoundted for. In this model, a film of thickness h, smaller than
the coil size, can show either a "sandwich" structure with two mobile sublayers
(at low temperatures T<T(h)), or a single mobile layer at T>T(h). But the
accident occurring at T=T(h), does not necessarily coincide with the apparent
glass transition, determined by the intersection of two tangents in a plot of
thickness versus temperature.

</DOC>
<DOC>
<DOCNO> 83047 </DOCNO>
Computational Geometry Column 38


  Recent results on curve reconstruction are described.

</DOC>
<DOC>
<DOCNO> 40618 </DOCNO>
Electrooptical Detection of Charged Particles


  We have made the first observation of a charged particle beam by means of its
electro-optical effect on the polarization of laser light in a LiNbO3 crystal.
The modulation of the laser light during the passage of a pulsed electron beam
was observed using a fast photodiode and a digital oscilloscope. The fastest
rise time measured, 120 ps, was obtained in the single shot mode and was
limited by the bandwidth of the oscilloscope and the associated electronics.
This technology holds promise for detectors of greatly improved spatial and
temporal resolution for single relativistic charged particles as well as
particle beams.

</DOC>
<DOC>
<DOCNO> 10271 </DOCNO>
Circuit theory of multiple Andreev reflections in diffusive SNS


  The incoherent regime of Multiple Andreev Reflections (MAR) is studied in
long diffusive SNS junctions at applied voltages larger than the Thouless
energy. Incoherent MAR is treated as a transport problem in energy space by
means of a circuit theory for an equivalent electrical network. The current
through NS interfaces is explained in terms of diffusion flows of electrons and
holes through tunnel and Andreev resistors. These resistors in diffusive
junctions play roles analogous to the normal and Andreev reflection
coefficients in OTBK theory for ballistic junctions. The theory is applied to
the subharmonic gap structure (SGS); simple analytical results are obtained for
the distribution function and current spectral density for the limiting cases
of resistive and transparent NS interfaces. In the general case, the exact
solution is found in terms of chain-fractions, and the current is calculated
numerically. SGS shows qualitatively different behavior for even and odd
subharmonic numbers, and the maximum slopes of the differential resistance
correspond to the gap subharmonics. The influence of inelastic scattering on
the subgap anomalies of the differential resistance is analyzed.

</DOC>
<DOC>
<DOCNO> 71149 </DOCNO>
Leading logarithmic contribution to the second-order Lamb shift induced


  Contribution of order \alpha^2 (Z \alpha)^6 \ln^3(Z \alpha)^{-2} to the
ground-state Lamb shift in hydrogen induced by the loop-after-loop diagram is
evaluated analytically. An additional contribution of this order is found
compared to the previous calculation by Karshenboim [JETP 76, 541 (1993)]. As a
result, an agreement is achieved for this correction between different
numerical and analytical methods.

</DOC>
<DOC>
<DOCNO> 12796 </DOCNO>
Scattering properties of a cut-circle billiard waveguide with two


  We examine a two-dimensional electron waveguide with a cut-circle cavity and
conical leads. By considering Wigner delay times and the Landauer-B\"{u}ttiker
conductance for this system, we probe the effects of the closed billiard energy
spectrum on scattering properties in the limit of weakly coupled leads. We
investigate how lead placement and cavity shape affect these conductance and
time delay spectra of the waveguide.

</DOC>
<DOC>
<DOCNO> 174437 </DOCNO>
Similarity of multifragmentation of Au and Kr residual nucleus


  Experimental data on multi-fragmentation of residual krypton nuclei created
in the interactions of the krypton nuclei with photoemulsion nuclei at the
energy of 0.9 GeV per nucleon are presented in a comparison with the analogous
data on fragmentation of gold residual nuclei at the energy of 10.7
GeV/nucleon. It is shown for the first time that there are two regimes of
nuclear multifragmentation: the former is when less than one-half of nucleons
of projectile nucleus are knocked out, the latter is when more than one-half of
nucleons are knocked out. Residual nuclei with closed masses created at
different reactions are fragmenting practically simultaneously when more than
one-half of nucleons of original nuclei are knocked out. The evidence of
existence of a radial flow of the spectator fragment at the decay of residual
krypton nuclei is found.

</DOC>
<DOC>
<DOCNO> 69301 </DOCNO>
Current Issues in Heavy Quark Production


  We discuss heavy quark production in deep inelastic scattering (DIS)

</DOC>
<DOC>
<DOCNO> 13115 </DOCNO>
Coexistence of 0 and $\pi$ states in Josephson junctions


  New modes of the magnetic flux penetration in SQUIDs with ferromagnetic
junctions are predicted theoretically. Characteristic multinode anharmonicity
of the current-phase relation implies the coexistence of stable and metastable
0 and $\pi$ states for a large interval of strength of the ferromagnetic
barrier influence at low temperature. As a consequence, the coexistence of
integer and half-integer fluxoid configurations appears in both rf and dc
SQUIDs, and generates two flux jumps per one external flux quantum. In dc
SQUIDs, new flux jumps are manifested as two dips in the critical current
dependence on the external magnetic flux.

</DOC>
<DOC>
<DOCNO> 70938 </DOCNO>
Pion loop fluctuations of constituent quarks and baryons


  The implications of the pion (meson) degrees of freedom for baryon
properties, taken at the constituent quark and baryon levels are compared. It
is shown that there is a dramatic qualitative difference between two
approaches.

</DOC>
<DOC>
<DOCNO> 118591 </DOCNO>
The Tip of the Red Giant Branch and Distance of the Magellanic Clouds:


  We present a precise determination of the apparent magnitude of the tip of
the red giant branch (TRGB) in the I (0.8 micron), J (1.25 micron), and K_S
(2.15 micron) bands from the luminosity function of a sample of data extracted
from the DENIS catalogue towards the Magellanic Clouds (Cioni et al. 2000).
  From the J and Ks magnitudes we derive bolometric magnitudes m_bol. We
present a new algorithm for the determination of the TRGB magnitude, which we
describe in detail and test extensively using Monte-Carlo simulations. We note
that any method that searches for a peak in the first derivative (used by most
authors) or the second derivative (used by us) of the observed luminosity
function does not yield an unbiased estimate for the actual magnitude of the
TRGB discontinuity. We stress the importance of correcting for this bias, which
is not generally done. We combine the results of our algorithm with theoretical
predictions to derive the distance modulus of the Magellanic Clouds. We obtain
m-M = 18.55 (0.04 formal, 0.08 systematic) for the Large Magellanic Cloud
(LMC), and m-M = 18.99 (0.03 formal, 0.08 systematic) for the Small Magellanic
Cloud (SMC). These are among the most accurate determinations of these
quantities currently available, which is a direct consequence of the large size
of our sample and the insensitivity of near infrared observations to dust
extinction.

</DOC>
<DOC>
<DOCNO> 11748 </DOCNO>
Millimeter-Wave Spectroscopy of the Organic spin-Peierls System


  The first purely organic BEDT-TTF spin-Peierls system, b'-(ET)2SF5CF2SO3, has
been confirmed using a high-frequency electron spin resonance (EPR) cavity
perturbation technique. The material exhibits the characteristics of a
quasi-one-dimensional (1D) Heisenberg antiferromagnetic spin system above 30 K,
but undergoes a second-order transition, at TSP = 33 K, to a singlet ground
state, due to a progressive spin-lattice dimerization. The spin-Peierls state
is evidenced by a sharp drop in the spin susceptibility below 24 K for the
magnetic field parallel to each of the three principle axes (i.e. H7a, H7b, and
H7c). The 1D chain axis has been identified as the crystallographic b axis from
the g value analysis. The singlet-triplet gap, Ds(0) = 114 (+-21)K, was
determined using a modified BCS theory. Also, we describe in some detail the
millimeter-wave vector network analyzer (MVNA) for researchers who have
interest in precision EPR measurements at higher magnetic fields and
frequencies.

</DOC>
<DOC>
<DOCNO> 11999 </DOCNO>
c(2x2) Interface Alloys in Co/Cu Multilayers - Influence on Interlayer


  The influence of a c(2x2) ordered interface alloy of 3d transition metals at
the ferromagnet/nonmagnet interface on interlayer exchange coupling (IXC), the
formation of quantum well states (QWS) and the phenomenon of Giant
MagnetoResistance is investigated. We obtained a strong dependence of IXC on
interface alloy formation. The GMR ratio is also strongly influenced. We found
that Fe, Ni and Cu alloys at the interface enhance the GMR ratio for in-plane
geometry by nearly a factor of 2.

</DOC>
<DOC>
<DOCNO> 71875 </DOCNO>
On the Determination of the Polarized Sea Distributions of the Nucleon


  The possibilities to determine the flavor structure of the polarized sea
(antiquark) distributions of the nucleon via vector boson $(\gamma^*, W^{\pm},
Z^0)$ production at high energy polarized hadron--hadron colliders, such as the
Relativistic Heavy--Ion Collider (RHIC), are studied in detail. In particular
the perturbative stability of the expected asymmetries in two representative
models for the (un)broken flavor structure are investigated by confronting
perturbative QCD leading order predictions of the expected asymmetries with
their next--to--leading order counterparts.

</DOC>
<DOC>
<DOCNO> 118684 </DOCNO>
Detectability of Gravitational Radiation from Prompt and Delayed Star


  We consider the emission of gravitational waves in the two proposed models
for the collapse of a massive star to a black hole: the prompt collapse, in
which nearly all the star collapses to a black hole in a dynamical time scale,
and the delayed collapse, in which a light black hole, or a neutron star, which
subsequently accretes matter, forms due to the fall-back achieving, in the
neutron star case, the critical mass for black hole formation. Recent
simulations strongly support this last scenario. We show that, due to the
slowness of fall-back, in the delayed collapse the main burst of gravitational
radiation is emitted depending on the parameters, mass and angular momentum, of
the initial, light, black hole. We estimate, under different assumptions, the
detectability of the emitted gravitational waves showing that such kind of
collapse is not particularly suited for detection by forthcoming
interferometric detectors. Detectors with high sensitivity at frequencies
greater than ~4-5 kHz would be well suited for this kind of sources. We
calculate also the final mass distribution function of single black holes.

</DOC>
<DOC>
<DOCNO> 100204 </DOCNO>
Spinor Representations of Surfaces in 4-Dimensional Pseudo-Riemannian


  Spinor representations of surfaces immersed into 4-dimensional
pseudo-riemannian manifolds are defined in terms of minimal left ideals and
tensor decompositions of Clifford algebras. The classification of spinor fields
and Dirac operators on the immersed surfaces is given. The Dirac-Hestenes
spinor field on surfaces immersed into Lorentzian manifolds and on surfaces
conformally immersed into Minkowski spacetime is defined.

</DOC>
<DOC>
<DOCNO> 71967 </DOCNO>
Study of Radiative Leptonic D Meson Decays


  We study the radiative leptonic $D$ meson decays of $D^+_{(s)}\to
\l^+\nu_{\l}\gamma$ ($\l=e,\mu,\tau$), $D^0\to \nu\bar{\nu}\gamma$ and $D^0\to
\l^+\l^-\gamma$ ($l=e,\mu$) within the light front quark model. In the standard
model, we find that the decay branching ratios of $D^+_{(s)}\to
e^+\nu_e\gamma$, $D^+_{(s)}\to\mu^+\nu_{\mu}\gamma$ and
$D^+_{(s)}\to\tau^+\nu_{\tau}\gamma$ are $6.9\times 10^{-6}$ ($7.7\times
10^{-5}$), $2.5\times 10^{-5}$ ($2.6\times 10^{-4}$), and $6.0\times 10^{-6}$
($3.2\times 10^{-4}$), and that of $D^0\to\l^+\l^-\gamma$ ($\l=e,\mu$) and
$D^0\to\nu\bar{\nu}\gamma$ are $6.3\times 10^{-11}$ and $2.7\times 10^{-16}$,
respectively.

</DOC>
<DOC>
<DOCNO> 117206 </DOCNO>
Comments on Superluminal Laser Pulse Propagation


  Researchers claim to have observed superluminal (faster than light)
propagation of a laser pulse in a gain medium by a new mechanism in which there
is no distortion of the pulse [Nature, 406, 277 (2000)]. Our analysis shows
that the observed mechanism is due to pulse distortion arising from a
differential gain effect and should not be viewed as superluminal propagation.

</DOC>
<DOC>
<DOCNO> 99921 </DOCNO>
Isomonodromic deformations in genus zero and one: algebrogeometric


  Here we review some recent developments in the theory of isomonodromic
deformations on Riemann sphere and elliptic curve. For both cases we show how
to derive
 Schlesinger transformations together with their action on tau-function, and
construct classes of solutions in terms of multi-dimensional theta-functions.

</DOC>
<DOC>
<DOCNO> 39812 </DOCNO>
About EAS size spectra and primary energy spectra in the knee region


  Based on the unified analyses of KASCADE, AKENO, EAS-TOP and ANI EAS size
spectra, the approximations of energy spectra of different primary nuclei have
been found. Calculations were carried out using SIBYLL and QGSJET interaction
models in 0.1-100 PeV primary energy range. The results point to existence of
both rigidity-dependent steepening energy spectra at R=200-400 TV and an
additional proton (neutron) component with differential energy spectrum
(6.1+/-0.7)10^{-11}(E/Ek)^{-1.5} (m^2.s.sr.TeV)^{-1} before the knee
Ek=2030+/-130 TeV and with power index g2=-3.1+/-0.05 after the knee.

</DOC>
<DOC>
<DOCNO> 151972 </DOCNO>
Instantons in non-Cartesian coordinates


  The explicit multi-instanton solutions by 'tHooft and Jackiw, Nohl & Rebbi
are generalized to curvilinear coordinates. The idea is that a gauge
transformation can notably simplify the expressions obtained after the change
of variables. The gauge transform generates a compensating addition to the
gauge potential of pseudoparticles. Singularities of the compensating field are
irrelevant for physics but may affect gauge dependent quantities.

</DOC>
<DOC>
<DOCNO> 121804 </DOCNO>
The Anthropic Argument against Infinite Past and the Eddington-Lemaitre


  This study in the philosophy of cosmology is a part of an ongoing effort to
investigate and reassess the importance of the anthropic (Davies-Tipler)
argument against cosmologies containing the past temporal infinity. Obviously,
the prime targets of this argument are cosmological models stationary on
sufficiently large scale, the classical steady state model of Bondi, Gold and
Hoyle being the best example. Here we investigate the extension of application
of this argument to infinitely old non-stationary models and discuss additional
constraints necessary to be imposed on such models for the edge of the
anthropic argument to be preserved. An illustrative counterexample is the
classical Eddington-Lemaitre model, in the analysis of which major such
constraints are presented. Consequences of such an approach for our
understanding of the nature of time are briefly discussed.

</DOC>
<DOC>
<DOCNO> 170094 </DOCNO>
Separability of n-particle mixed states: necessary and sufficient


  We provide necessary and sufficient conditions for separability of mixed
states of n-particle systems. The conditions are formulated in terms of maps
which are positive on product states of $n-1$ particles. The method of
providing of the maps on the basis of unextendable product bases is provided.
The three qubit state problem is reformulated in the form suggesting
possibility of explicite characterisation of all maps needed for separability
condition.

</DOC>
<DOC>
<DOCNO> 69370 </DOCNO>
Chiral Vacuum Alignment in Dense QCD


  We discuss an interesting possibility of nontrivial, quark-mass induced
chiral vacuum alignment in color-flavor locking phase of cold, dense QCD. With
the simplifying assumption that the gaps for quarks are identical to those of
antiquarks and the light quark masses are given by $m_u = m_d$ and $
m_s/m_d=15$, we find the true chiral vacuum can align only to one of the
discrete number of directions in the continuum of chiral vacua. The alignment
depends on the size of the diquark condensates, and the vacuum transitions
between the discrete vacua caused by the evolution of the diquark condensates
can be first order phase transition with vanishing or nonvanishing latent heat,
depending on the vacua involved. It is also shown that as $\mu \to \infty$,
where $\mu$ is the baryon chemical potential, parity is spontaneously broken
through the vacuum alignment.

</DOC>
<DOC>
<DOCNO> 102860 </DOCNO>
Reflection principle and envelopes of holomorphy


  The reflection function of a smooth CR diffeomorphism between two minimal
real analytic hypersurfaces is everywhere real analytic.

</DOC>
<DOC>
<DOCNO> 70068 </DOCNO>
Final State Interactions in eps'/eps


  I shortly review the present status of the theoretical estimates of eps'/eps.
I consider a few aspects of the theoretical calculations which may be relevant
in understanding the present experimental results. In particular, I discuss the
role of final state interactions and in general of non-factorizable
contributions for the explanation of the Delta I = 1/2 selection rule in kaon
decays and eps'/eps. Lacking reliable lattice calculations, the 1/N expansion
and phenomenological approaches may help in understanding correlations among
theoretical effects and the experimental data. The same dynamics which
underlies the CP conserving selection rule may drive eps'/eps in the range of
the recent experimental measurements.

</DOC>
<DOC>
<DOCNO> 102338 </DOCNO>
A universal weasel without large cardinals in V


  We prove in the theory "ZFC + there is no inner model with a Woodin cardinal"
that there is a universal weasel. This shows in particular that one doesn't
have to assume the existence of large cardinals in V to prove the existence of
some such weasel.

</DOC>
<DOC>
<DOCNO> 11195 </DOCNO>
Comment on ``Statistics of the Lyapunov Exponent in 1D random


  In this paper we comment the results of ``Statistics of the Lyapunov Exponent
in 1D random periodic-on-Average Systems" [Phys. Rev. Lett. {\bf 81}, 5390,
1998].

</DOC>
<DOC>
<DOCNO> 179009 </DOCNO>
Point Form Electrodynamics and the Gupta-Bleuler Formalism


  The Gupta-Bleuler formalism for photons is derived from induced
representation theory. The representation for the little group for massless
particles, the two dimensional Euclidian group, is chosen to be the four
dimensional nonunitary representation obtained by restricting elements of the
Lorentz group to the Euclidian group. Though the little group representation is
nonunitary, it is shown that the representation of the Poincar\'{e} group is
unitary. As a consequence of the four dimensional representation, the
polarization vector, which connects the four-vector potential with creation and
annihilation operators, is given in terms of boosts, coset representatives of
the Lorentz group with respect to the Euclidian group. Several polarization
vectors (boost choices) are worked out, including a front form polariation
vector. The different boost choices are shown to be related by the analogue of
Melosh rotations, namely Euclidian group transformations.

</DOC>
<DOC>
<DOCNO> 67901 </DOCNO>
Some Astrophysical Implications of Compact Extra Dimensions


  There have been many suggestions that there are extra spatial dimensions
"outside" of our normal (3+1)-dimensional space. Generally it is assumed that
electromagnetic and hadronic fields are restricted to the normal dimensions,
while gravity can extend into the extra dimensions. Thus a hadron or lepton is
confined in a potential well, and excited states should exist. I explore the
possibility that ordinary hadrons and leptons have excited states
("compactons"), some of which may have electromagnetism and possibly gravity
confined to the extra spatial dimensions. Some of these may be long-lived. If
sufficiently long-lived, relic compactons may exist as dark matter. Black holes
may be the source of new particles with bizarre properties that appear as UHE
cosmic rays.

</DOC>
<DOC>
<DOCNO> 102901 </DOCNO>
Eigenvalues of the Dirac Operator on Manifolds with Boundary


  Under standard local boundary conditions or certain global APS boundary
conditions, we get lower bounds for the eigenvalues of the Dirac operator on
compact spin manifolds with boundary. Limiting cases are characterized by the
existence of real Killing spinors and the minimality of the boundary.

</DOC>
<DOC>
<DOCNO> 8011 </DOCNO>
(Meta-)stable reconstructions of the diamond(111) surface: interplay


  Off-lattice Grand Canonical Monte Carlo simulations of the clean diamond
(111) surface, based on the effective many-body Brenner potential, yield the
$(2\times1)$ Pandey reconstruction in agreement with \emph{ab-initio}
calculations and predict the existence of new meta-stable states, very near in
energy, with all surface atoms in three-fold graphite-like bonding. We believe
that the long-standing debate on the structural and electronic properties of
this surface could be solved by considering this type of carbon-specific
configurations.

</DOC>
<DOC>
<DOCNO> 68842 </DOCNO>
Quasirotational Motions and Stability Problem in Dynamics of String


  For the relativistic string with massive ends (the meson model) and four
various string baryon models (q-qq, q-q-q, Y and $\Delta$) we consider the
classical quasirotational motions, which are small disturbances of the planar
uniform rotations of these systems. For the string meson model the two types of
these solutions are obtained. They describe oscillatory motions in the form of
stationary waves in the rotational plane and in the orthogonal direction. This
approach and the suggested method of determining an arbitrary motion of the
system on the base of initial data let us solve the stability problem for the
rotational motions for all mentioned string configurations. It is shown that
the classic rotational motions are {\it stable} for the string meson model (or
its analog q-qq) and for the $\Delta$ baryon configuration, but they are {\it
unstable} for the string baryon models Y and q-q-q. For the latter two systems
any small asymmetric disturbances grow with growing time. The motion of the
q-q-q configuration become more complicated and quasiperiodic but quarks do not
merge. In the case of Y model the evolution of disturbances results in falling
a quark into the junction. These features of the classic behavior are important
for describing the hadron states on the Regge trajectories and for choosing and
developing the most adequate QCD-based string hadron models.

</DOC>
<DOC>
<DOCNO> 8791 </DOCNO>
Scaling of interfaces in brittle fracture and perfect plasticity


  The roughness properties of two-dimensional fracture surfaces as created by
the slow failure of random fuse networks are considered and compared to yield
surfaces of perfect plasticity with similar disorder. By studying systems up to
a linear size L=350 it is found that in the cases studied the fracture surfaces
exhibit self-affine scaling with a roughness exponent close to 2/3, which is
asymptotically exactly true for plasticity though finite-size effects are
evident for both. The overlap of yield or minimum energy and fracture surfaces
with exactly the same disorder configuration is shown to be a decreasing
function of the system size and to be of a rather large magnitude for all cases
studied. The typical ``overlap cluster'' length between pairs of such
interfaces converges to a constant with $L$ increasing.

</DOC>
<DOC>
<DOCNO> 170222 </DOCNO>
Entangling operations and their implementation using a small amount of


  We study when a physical operation can produce entanglement between two
systems initially disentangled. The formalism we develop allows to show that
one can perform certain non-local operations with unit probability by
performing local measurement on states that are weakly entangled.

</DOC>
<DOC>
<DOCNO> 120281 </DOCNO>
The emission nebula associated with V1974 Cyg: a unique object?


  Through a program of narrow band imaging, we have observed the changing
structure of the H alpha emission line around Nova Cyg 1992 (V1974 Cyg) at
regular intervals from 1996 to 1999. Between 1994 and 1996, the nebular
boundary advanced to the southwest at nearly the speed of light, implying that
the nebula was created by an expanding wave of radiation originating in the
explosion interacting with surrounding material. The expansion speed dropped to
0.35c during 1996-1999. We have taken spectra of the nebula in 1998 and 1999.
Only Balmer lines are detected, no He I, [OIII], [OII], [NII], or [SII]. There
is also no trace of the high excitation nova lines (He II, NeV, etc). These
spectra show that the nebula is NOT a reflection nebula, a conventional HII
region, or a shock involving motions of the gas. The integrated H alpha
luminosity of the nebula between 1996 and 1999 is in the range =~1.3-2.2 x
10(35) erg s(-1). The density is poorly determined, but is probably very large
(10(4) cm(-3)) in order to explain the brightest region of the nebula. The
dynamical timescale is about a year and the recombination timescale of the same
order. Bright patches are observed to fade in these times. The energy required
to ionize the nebula is the bolometric luminosity of the nova for 30 days,
smaller than the time during which the temperature of the nova photosphere was
in the right range to produce the ionizing photons. We have also undertaken
sensitive surveys of H alpha nebulae around recent novae but find no evidence
of other such nebulae, so this type of object must be rare.

</DOC>
<DOC>
<DOCNO> 84111 </DOCNO>
Areas of the Event Horizon and Stationary Limit Surface for a Kerr Black


  We present an elementary evaluation of the surface areas of the event horizon
and stationary limit surface for an uncharged Kerr black hole. The latter
appears not to have been previously given in the literature, and permits us to
suggest new geometrical / physical interpretations of these areas.

</DOC>
<DOC>
<DOCNO> 11472 </DOCNO>
Fate of Zero-Temperature Ising Ferromagnets


  We investigate the relaxation of homogeneous Ising ferromagnets on finite
lattices with zero-temperature spin-flip dynamics. On the square lattice, a
frozen two-stripe state is apparently reached approximately 1/4 of the time,
while the ground state is reached otherwise. The asymptotic relaxation is
characterized by two distinct time scales, with the longer stemming from the
influence of a long-lived diagonal stripe ``defect''. In greater than two
dimensions, the probability to reach the ground state rapidly vanishes as the
size increases and the system typically ends up wandering forever within an
iso-energy set of stochastically ``blinking'' metastable states.

</DOC>
<DOC>
<DOCNO> 119605 </DOCNO>
Synchrotron Emission from Hot Accretion Flows and the Cosmic Microwave


  Current estimates of number counts of radio sources in the frequency range
where the most sensitive Cosmic Microwave Background (CMB) experiments are
carried out significantly under-represent sources with strongly inverted
spectra. Hot accretion flows around supermassive black holes in the nuclei of
nearby galaxies are expected to produce inverted radio spectra by thermal
synchrotron emission. We calculate the temperature fluctuations and power
spectra of these sources in the Planck Surveyor 30 GHz energy channel, where
their emission is expected to peak. We find that their potential contribution
is generally comparable to the instrumental noise, and approaches the CMB
anisotropy level at small angular scales. Forthcoming CMB missions, which will
provide a large statistical sample of inverted-spectra sources, will be crucial
for determining the distribution of hot accretion flows in nearby quiescent
galactic nuclei. Detection of these sources in different frequency channels
will help constrain their spectral characteristics, hence their physical
properties.

</DOC>
<DOC>
<DOCNO> 10234 </DOCNO>
Ground state energy of a non-integer number of particles with delta


  We show how to define and calculate the ground state energy of a system of
quantum particles with delta attractive interactions when the number of
particles n$is non-integer. The question is relevant to obtain the probability
distribution of the free energy of a directed polymer in a random medium. When
one expands the ground state energy in powers of the interaction, all the
coefficients of the perturbation series are polynomials in n, allowing to
define the perturbation theory for non-integer n. We develop a procedure to
calculate all the cumulants of the free energy of the directed polymer and we
give explicit, although complicated, expressions of the first three cumulants.

</DOC>
<DOC>
<DOCNO> 121758 </DOCNO>
Size-Luminosity scaling and Inverse Compton Seed Photons in Blazars


  We present preliminary results of our work on blazar unification. We assume
that all blazars have a broad line region (BLR) and that the size of the BLR
scales with the power of the source in a manner similar to that derived through
reverberation mapping in radio quiet active galactic nuclei (AGNs). Using a
self-consistent emission model that includes particle acceleration we show that
according to this scaling, in weak sources like MKN 421, the inverse Compton
(IC) scattering losses are dominated by synchrotron-self Compton scattering
(SSC), while in powerful sources, like 3C 279, they are dominated by external
Compton (EC) scattering of BLR photons. In agreement with other workers, we
show that even in the powerful sources that are dominated by EC scattering, the
hard X-ray emission is due to SSC. Finally, we show that this scaling
reproduces well the observed sequence of blazar properties with luminosity.

</DOC>
<DOC>
<DOCNO> 122633 </DOCNO>
The heavy-element abundances of AGB stars and the angular momentum


  Adpoting new s-process nucleosynthesis scenario and branch s-process path, we
calculate the heavy-element abundances and C/O ratio of solar metallicity
3M_sun TP-AGB stars. The evolutionary sequence from M to S to C stars of AGB
stars is explained naturally by the calculated results. Then combining the
angular momentum conservation model of wind accretion with the heavy-element
abundances on the surface of TP-AGB stars, we calculate the heavy-element
overabundances of barium stars via successive pulsed accreting and mixing. Our
results support that the barium stars with longer orbital period, P>1600 days,
form through wind accretion scenario.

</DOC>
<DOC>
<DOCNO> 170265 </DOCNO>
Raman Excited Spin Coherences in N-V Diamond


  Raman excited spin coherences were experimentally observed in N-V diamond
color centers via nondegenerate four-wave mixing (NDFWM) and
electromagnetically induced transparency (EIT). The maximal absorption
suppression was found to be 17%, which corresponds to 70% of what is possible
given the random geometric orientation of the N-V center in diamond. In the
context of quantum computing in solids, this level of transparency represents
the efficient preparation of quantum bits (qubits), as well as ability to
perform arbitrary single qubit rotations.

</DOC>
<DOC>
<DOCNO> 7818 </DOCNO>
Amorphization of Vortex Matter and Reentrant Peak Effect in


  The peak effect (PE) has been observed in a twinned crystal of
YBa$_2$Cu$_3$O$_{7-\delta}$ for H$\parallel$c in the low field range, close to
the zero field superconducting transition temperature (T$_c$(0)) . A sharp
depinning transition succeeds the peak temperature T$_p$ of the PE. The PE
phenomenon broadens and its internal structure smoothens out as the field is
increased or decreased beyond the interval between 250 Oe and 1000 Oe.
Moreover, the PE could not be observed above 10 kOe and below 20 Oe. The locus
of the T$_p$(H) values shows a reentrant characteristic with a nose like
feature located at T$_p$(H)/T$_c$(0)$\approx$0.99 and H$\approx$100 Oe (where
the FLL constant a$_0$$\approx$penetration depth $\lambda$). The upper part of
the PE curve (0.5 kOe$<$H$<$10 kOe) can be fitted to a melting scenario with
the Lindemann number c$_L$$\approx$0.25. The vortex phase diagram near T$_c$(0)
determined from the characteristic features of the PE in
YBa$_2$Cu$_3$O$_{7-\delta}$(H$\parallel$c) bears close resemblance to that in
the 2H-NbSe$_2$ system, in which a reentrant PE had been observed earlier.

</DOC>
<DOC>
<DOCNO> 12031 </DOCNO>
Jarzynski Relations for Quantum Systems and Some Applications


  We derive quantum analogues of Jarzynski's relations, and discuss two
applications, namely, a derivation of the law of entropy increase for general
compound systems, and a preliminary analysis of heat transfer between two
quantum systems at different temperatures. We believe that the derivation of
the law of entropy increase is new and of importance.

</DOC>
<DOC>
<DOCNO> 10470 </DOCNO>
Is dynamic ultrametricity observable in spin glasses?


  We investigate the dynamics of spin glasses from the `rheological' point of
view, in which aging is suppressed by the action of small, non-conservative
forces. The different features can be expressed in terms of the scaling of
relaxation times with the magnitude of the driving force, which plays the role
of the critical parameter. Stated in these terms, ultrametricity loses much of
its mystery and can be checked rather easily. This approach also seems a
natural starting point to investigate what would be the real-space structures
underlying the hierarchy of time scales. We study in detail the appearance of
this many-scale behavior in a mean-field model, in which dynamic ultrametricity
is clearly present. A similar analysis is performed on numerical results
obtained for a 3D spin glass: In that case, our results are compatible with
either that dynamic ultrametricity is absent or that it develops so slowly that
even in experimental time-windows it is still hardly observable.

</DOC>
<DOC>
<DOCNO> 151399 </DOCNO>
A class of six-dimensional conformal field theories


  We describe a class of six-dimensional conformal field theories that have
some properties in common with and possibly are related to a subsector of the
tensionless string theories. The latter theories can for example give rise to
four-dimensional $N = 4$ superconformal Yang-Mills theories upon
compactification on a two-torus. Just like the tensionless string theories, our
theories have an $ADE$-classification, but no other discrete or continuous
parameters. The Hilbert space carries an irreducible representation of the same
Heisenberg group that appears in the tensionless string theories, and the
`Wilson surface' observables obey the same superselection rules. When
compactified on a two-torus, they have the same behaviour under $S$-duality as
super Yang-Mills theory. Our theories are natural generalizations of the
two-form with self-dual field strength that is part of the world-volume theory
of a single five-brane in $M$-theory, and the $A_{N - 1}$ theory can in fact be
seen as arising from $N$ non-interacting chiral two-forms by factoring out the
collective `center of mass' degrees of freedom.

</DOC>
<DOC>
<DOCNO> 117028 </DOCNO>
Simulation of the Beam-Beam Effects in $e^+e^-$ Storage Rings with a


  A highly accurate self-consistent particle code to simulate the beam-beam
collision in $e^+e^-$ storage rings has been developed. It adopts a method of
solving the Poisson equation with an open boundary. The method consists of two
steps: assigning the potential on a finite boundary using the Green's function,
and then solving the potential inside the boundary with a fast Poisson solver.
Since the solution of the Poisson's equation is unique, our solution is exactly
the same as the one obtained by simply using the Green's function. The method
allows us to select much smaller region of mesh and therefore increase the
resolution of the solver. The better resolution makes more accurate the
calculation of the dynamics in the core of the beams. The luminosity simulated
with this method agrees quantitatively with the measurement for the PEP-II
B-factory ring in the linear and nonlinear beam current regimes, demonstrating
its predictive capability in detail.

</DOC>
<DOC>
<DOCNO> 151937 </DOCNO>
Closed Sub-Monodromy Problems, Local Mirror Symmetry and Branes on


  We study D-branes wrapping an exceptional four-cycle P(1,a,b) in a blown-up
C^3/Z_m non-compact Calabi-Yau threefold with (m;a,b)=(3;1,1), (4;1,2) and
(6;2,3). In applying the method of local mirror symmetry we find that the
Picard-Fuchs equations for the local mirror periods in the Z_{3,4,6} orbifolds
take the same form as the ones in the local E_{6,7,8} del Pezzo models,
respectively. It is observed, however, that the orbifold models and the del
Pezzo models possess different physical properties because the background NS
B-field is turned on in the case of Z_{3,4,6} orbifolds. This is shown by
analyzing the periods and their monodromies in full detail with the help of
Meijer G-functions. We use the results to discuss D-brane configurations on
P(1,a,b) as well as on del Pezzo surfaces. We also discuss the number theoretic
aspect of local mirror symmetry and observe that the exponent which governs the
exponential growth of the Gromov-Witten invariants is determined by the special
value of the Dirichlet L-function.

</DOC>
<DOC>
<DOCNO> 80600 </DOCNO>
Axial anomaly and Ginsparg-Wilson fermions in the Lattice Dirac Sea


  The axial anomaly equation in 1+1 dimensional QED is obtained on the lattice
for fermions obeying the Ginsparg-Wilson relation. We make use of the
properties of the Lattice Dirac sea to investigate the connection between the
anomaly and the Ginsparg-Wilson operator in the Hamiltonian picture. The
correct anomaly is reproduced for gauge fields whose characteristic time is
much larger than the lattice spacing, which is the regime where the adiabatic
approximation applies. A non-zero Wilson $r$ parameter is necessary to get the
correct anomaly. The anomaly is shown to be independent of $r$ for $r>0.5$. The
generalization to 3+1 dimensions is also discussed.

</DOC>
<DOC>
<DOCNO> 84468 </DOCNO>
Inflationary Universe in Higher Derivative Induced Gravity


  In an induced-gravity model, the stability condition of an inflationary
slow-rollover solution is shown to be $\phi_0
\partial_{\phi_0}V(\phi_0)=4V(\phi_0)$. The presence of higher derivative terms
will, however, act against the stability of this expanding solution unless
further constraints on the field parameters are imposed. We find that these
models will acquire a non-vanishing cosmological constant at the end of
inflation. Some models are analyzed for their implication to the early
universe.

</DOC>
<DOC>
<DOCNO> 85392 </DOCNO>
Wideband dual sphere detector of gravitational waves


  We present the concept of a sensitive AND broadband resonant mass
gravitational wave detector. A massive sphere is suspended inside a second
hollow one. Short, high-finesse Fabry-Perot optical cavities read out the
differential displacements of the two spheres as their quadrupole modes are
excited. At cryogenic temperatures one approaches the Standard Quantum Limit
for broadband operation with reasonable choices for the cavity finesses and the
intracavity light power. A molybdenum detector of overall size of 2 m, would
reach spectral strain sensitivities of 2x10^-23/Sqrt{Hz} between 1000 Hz and
3000 Hz.

</DOC>
<DOC>
<DOCNO> 150693 </DOCNO>
SU(2) Gauge Theory in Covariant (Maximal) Abelian Gauges


  The local covariant continuum action of an SU(2) gauge theory in covariant
Abelian gauges is investigated. It describes the critical limit of an Abelian
Lattice Gauge Theory (LGT) with an equivariant BRST-symmetry. This Abelian LGT
has previously been proven to be physically equivalent to the SU(2)-LGT.
Renormalizability requires a quartic ghost interaction in these nonlinear
gauges (also in maximal Abelian gauge). Arguments that a certain global SL(2,R)
symmetry is dynamically broken by ghost-antighost condensation in a BCS-like
mechanism are presented. The scenario can be viewed as a dynamical Higgs
mechanism in the adjoint that gives massive off-diagonal gluons and a BRST
quartet of Goldstone bosonsthat decouples from physical observables. The gap
parameter is related to the expectation value of the trace anomaly and the
consistency of this scenario with the Operator Product Expansion is discussed.

</DOC>
<DOC>
<DOCNO> 120482 </DOCNO>
Two BeppoSAX observations of BL Lac


  We present the results of two ToO BeppoSAX observations of BL Lac. During the
first observation we detected both the synchrotron and the Compton components.
Fast time variability was present, but only for the synchrotron component.
During the second observation the spectrum was flatter and only the Compton
component was present. Four different SED are presented and can be described by
a blob moving along a jet and responsible for the SSC emission. The seed
photons for the Compton scattering are the synchrotron photons themself plus
possibly external photons coming from the broad line region.

</DOC>
<DOC>
<DOCNO> 117466 </DOCNO>
The Lake Baikal neutrino experiment


  We rewiew the present status of the Baikal Neutrino Project and present the
results of a search for high energy neutrinos with the detector intermediate
stage NT-96.

</DOC>
<DOC>
<DOCNO> 99945 </DOCNO>
Wavelets and Quantum Algebras


  Wavelets, known to be useful in non-linear multi-scale processes and in
multi-resolution analysis, are shown to have a q-deformed algebraic structure.
The translation and dilation operators of the theory associate with any scaling
equation a non-linear, two parameter algebra. This structure can be mapped onto
the quantum group $su_{q}(2)$ in one limit, and approaches a Fourier series
generating algebra, in another limit. A duality between any scaling function
and its corresponding non-linear algebra is obtained. Examples for the Haar and
B-wavelets are worked out in detail.

</DOC>
<DOC>
<DOCNO> 7633 </DOCNO>
Critical exponents at the superconductor-insulator transition in


  I obtain the inverse of the correlation length exponent at the
superfluid-Bose glass quantum critical point as a series in small parameter
$\sqrt{d-1}$, with d being the dimensionality of the system, and compute the
first two terms using a novel field-theoretic technique. For d=2 I find $\nu_s
= 0.81$ and $\nu_c = 1.03$, for short-range and Coulomb interactions between
bosons, respectively. When combined with the exact values of the dynamical
critical exponents $z_s = d$ and $z_c = 1$, these results are in quantitative
agreement with the experiments on onset of superfluidity in $^4 He$ in porous
glasses, and on superconductor-insulator transition in homogeneous metallic
films, in support of the dirty-boson theory fot the latter. Higher-order
calculation of the exponents and of the universal conductivity is discussed.

</DOC>
<DOC>
<DOCNO> 169633 </DOCNO>
Quantum Anti-Cloning


  We derive the transformation for the optimal universal quantum anti-cloner
which produces two anti-parallel outputs for a single input state. The fidelity
is shown to be 2/3 which is same as the measurement fidelity. We consider a
probabilistic quantum anti-cloner and show quantum states can be anti-cloned
exactly with non-zero probability and its efficiency is higher than the
efficiency of distinguishing between the two states.

</DOC>
<DOC>
<DOCNO> 122852 </DOCNO>
Evidence Against a Redshift z>6 for the Galaxy STIS 123627+621755


  The identification of galaxies at extreme distances provides our most direct
information on the earliest phases of galaxy formation. The distance implied by
redshifts z > 5 makes this a challenging endeavor for even the most luminous
sources; interpretation of low signal-to-noise ratio observations of faint
galaxies is difficult and occasional misidentifications will occur. Here we
report on STIS 123627+621755, a galaxy with a suggested spectroscopic redshift
of z = 6.68 and the most distant spectroscopically-identified object claimed.
For the suggested redshift and reported spectral energy distribution, the
galaxy should be essentially invisible shortward of 9300 Angstroms because the
intervening intergalactic medium absorbs essentially all light energetic enough
to ionize neutral hydrogen (lambda < (1 + z) x 912 Angstroms; the redshifted
Lyman limit). The galaxy should be relatively bright in the near-infrared with
f(nu) ~ 1 microJy. Here we report a detection of the galaxy at 6700 Angstroms,
below the Lyman limit for z = 6.68. We also report a non-detection at 1.2
microns, implying the flux has dropped by a factor of three or more between
rest 1216 Angstroms and rest 1560 Angstroms for z = 6.68. Our observations are
inconsistent with the suggested extreme distance of STIS 123627+621755 and
conservatively require z < 6.

</DOC>
<DOC>
<DOCNO> 85443 </DOCNO>
Stable evolution of a maximally sliced Schwarzschild spacetime using a


  We will present results of a long term stable evolution, to $t=1000m$, of a
maximally sliced Schwarzschild blackhole using a smooth lattice method.

</DOC>
<DOC>
<DOCNO> 69428 </DOCNO>
A Topcolor Jungle Gym


  We discuss an alternative to the topcolor seesaw mechanism. In our scheme,
all the light quarks carry topcolor, and there are many composite SU(2)
doublets. This makes it possible to get the observed top quark mass and
observed $SU(2) \times U(1)$ breaking in a way that is quite different from the
classic seesaw mechanism. We discuss a model of this kind that arises naturally
in the context of dynamically broken topcolor. There are many composite scalars
in a theory of this kind. This has important effects on the Pagels-Stokar
relation and the Higgs mass. We find $m_{\rm Higgs} < 330$ GeV, lighter than in
typical topcolor models. We also show that the electroweak singlet quarks in
such a model can be lighter than the corresponding quarks in a seesaw model.

</DOC>
<DOC>
<DOCNO> 121266 </DOCNO>
The magnetorotational instability across the dead zone of protoplanetary


  We examine the linear stability of a flow threaded by a weak, vertical
magnetic field in a disk with a keplerian rotation profile and a vertical
stratification of the ionization degree as that predicted for vast portions of
protoplanetary disks. A quasi-global analysis is carried out, where the form of
the perturbations in the vertical direction is determined. Considering the
ohmic magnetic diffusivity of the gas, the conditions leading to the
magnetorotational instability are analyzed as a function of the diffusivity at
the disk surfaces, its vertical profile and the strength of the unperturbed
magnetic field. For typical conditions believed to prevail in protoplanetary
disks at radial distances between 0.1 and 10 AU, where the so-called dead zone
is proposed to exist, we find that generally the instability is damped. This
implies that, if the MRI is considered the only possible source of turbulence
in protoplanetary disks, no viscous angular momentum transport occursat those
radii.

</DOC>
<DOC>
<DOCNO> 85574 </DOCNO>
Critical Collapse of Collisionless Matter in Spherical Symmetry


  We perform a numerical study of the critical regime for the general
relativistic collapse of collisionless matter in spherical symmetry. The
evolution of the matter is given by the Vlasov equation (or Boltzmann equation)
and the geometry by Einstein's equations. This system of coupled differential
equations is solved using a particle-mesh (PM) method. This method approximates
the distribution function which describes the matter in phase space with a set
of particles moving along the characteristics of the Vlasov equation. The
individual particles are allowed to have angular momentum different from zero
but the total angular momentum has to be zero to retain spherical symmetry.
  In accord wih previous work by Rein, Rendall and Schaeffer, our results give
some indications that the critical behaviour in this model is of Type I (the
smallest black hole in each family has a finite mass). For the families of
initial data that we have studied it seems that in the critical regime the
solution is a static spacetime with non-zero radial momentum for the individual
particles. We have also found evidence for scaling laws for the time that the
critical solutions spend in the critical regime.

</DOC>
<DOC>
<DOCNO> 101176 </DOCNO>
Hopf modules and their duals


  Free Hopf modules and bimodules over a bialgebra are studied with some
details. In particular, we investigate a duality in the category of bimodules
in this context. This gives the correspondence between Woronowicz's quantum Lie
algebra and algebraic vector fields.

</DOC>
<DOC>
<DOCNO> 170229 </DOCNO>
Multiparty multilevel Greenberger-Horne-Zeilinger states


  The proof of Bell's theorem without inequalities by Greenberger, Horne, and
Zeilinger (GHZ) is extended to multiparticle multilevel systems. The proposed
procedure generalizes previous partial results and provides an operational
characterization of the so-called GHZ states for multiparticle multilevel
systems.

</DOC>
<DOC>
<DOCNO> 101923 </DOCNO>
Cuntz-Krieger-Pimsner Algebras Associated with Amalgamated Free Product


  We give a construction of a nuclear $C^\ast$-algebra associated with an
amalgamated free product of groups, generalizing Spielberg's construction of a
certain Cuntz-Krieger algebra associated with a finitely generated free product
of cyclic groups. Our nuclear $C^\ast$-algebras can be identified with certain
Cuntz-Krieger-Pimsner algebras. We will also show that our algebras can be
obtained by the crossed product construction of the canonical actions on the
hyperbolic boundaries, which proves a special case of Adams' result about
amenability of the boundary action for hyperbolic groups. We will also give an
explicit formula of the $K$-groups of our algebras. Finally we will investigate
the relationship between the KMS states of the generalized gauge actions on our
$C^\ast$ algebras and random walks on the groups.

</DOC>
<DOC>
<DOCNO> 70500 </DOCNO>
Jet Quenching versus Jet Enhancement: A Quantitative Study of the


  We study the gluon radiation spectrum off a hard in-medium produced quark in
the multiple soft rescattering formalism of
Baier-Dokshitzer-Mueller-Peigne-Schiff, and of Zakharov (BDMPS-Z). Its
dependence on the quark and gluon energy, on the gluon transverse momentum, on
the in-medium pathlength and on the rescattering properties of the nuclear
medium is analyzed quantitatively. The two components of gluon radiation, the
hard vacuum radiation associated to the quark production vertex, and the
medium-induced rescattering contribution interfer destructively. For small
spatial extensions of the medium, this destructive interference overcompensates
the hard vacuum radiation, and the total medium-induced radiative energy loss
decreases proportional to L^3. Medium-induced gluon production dominates only
above a finite critical length which varies between 3 and more than 6 fm
depending on the rescattering properties of the medium. Deviations from the
BDMPS-L^2-behaviour persist above the critical length. The medium dependence of
the angular gluon distribution is dominated by Brownian transverse momentum
broadening. This results in a depletion of the low transverse momentum part of
both the hard and the medium-induced contribution. As a consequence, the
medium-induced energy loss outside a finite angular cone size can be more than
a factor two larger than the total medium-induced radiative energy loss. We
discuss implications of these results for the jet quenching signal in
relativistic heavy ion collisions at RHIC and LHC.

</DOC>
<DOC>
<DOCNO> 85398 </DOCNO>
A new approach to quantum gravity: a summary


  Quantum Electrodynamics (QED) has been so successful a theory that it is
taken as a model for the production of further quantum theories. However, when
the prescription for quantising electromagnetic interactions that so
successfully resulted in QED is applied to General Relativity the theory
obtained is not renormalizable. We derive a different method of quantising
classical electromagnetism which also results in QED. We call the method the
versatile method. We then apply the versatile method to General Relativity, in
particular the Einstein equation which equates a geometrical description
derivable from the metric to the energy-momentum-stress tensor, or as we shall
call it the matter tensor of the matter field. The method can be applied
provided that there is always a reference frame, which may differ with location
and time, where the matter tensor can be reduced to a mass density with the
other elements zero. We call such matter tensors simple. This restriction means
that the tensor can be put into one to one correspondence with the Dirac
current. When the versatile method of quantising a classical theory is applied
to General Relativity the theory that results is renormalizable. It is in fact
isomorphic to QED, provided that the temporal and a spatial co-ordinate are
exchanged.

</DOC>
<DOC>
<DOCNO> 12714 </DOCNO>
A perturbative approach to non-linearities in the information carried by


  We evaluate the mutual information between the input and the output of a two
layer network in the case of a noisy and non-linear analogue channel. In the
case where the non-linearity is small with respect to the variability in the
noise, we derive an exact expression for the contribution to the mutual
information given by the non-linear term in first order of perturbation theory.
Finally we show how the calculation can be simplified by means of a
diagrammatic expansion. Our results suggest that the use of perturbation
theories applied to neural systems might give an insight on the contribution of
non-linearities to the information transmission and in general to the neuronal
dynamics.

</DOC>
<DOC>
<DOCNO> 170435 </DOCNO>
A feasible "Kochen-Specker" experiment with single particles


  We present a simple experimental scheme which can be used to demonstrate an
all-or-nothing type contradiction between non-contextual hidden variables and
quantum mechanics. The scheme, which is inspired by recent ideas by Cabello and
Garcia-Alcaine, shows that even for a single particle, path and spin
information cannot be predetermined in a non-contextual way.

</DOC>
<DOC>
<DOCNO> 100394 </DOCNO>
Geodesic connectedness of semi-Riemannian manifolds


  The question whether a Riemannian manifold is geodesically connected can be
studied from geometrical as well as variational methods, and accurate results
can be obtained by using the associated distance and related properties of the
positive-definiteness. It is natural to state this problem in manifolds with
(possibly non-smooth) boundary, and some conditions on this boundary has been
studied.
  For Lorentzian manifolds, the results cannot be so general, and very
different techniques has been introduced which are satisfactory for some
classes of Lorentzian manifolds: spaceforms, disprisoning and pseudoconvex
manifolds, stationary, globally hyperbolic or multiwarped spacetimes... Some of
them are appliable to semi-Riemannian manifolds with higher index or even to
manifolds with just an affine connection.
  Our purpose is to review these semi-Riemannian techniques, discussing the
results and possible extensions.

</DOC>
<DOC>
<DOCNO> 11854 </DOCNO>
Conductivity of disordered electrons: Mean-field approximation


  The electrical {\em dc}-conductivity of disordered, non-interacting electrons
is calculated in the asymptotic limit of high lattice dimensions $d\to \infty$.
To go beyond the lowest-order contribution in the expansion parameter $1/d$ of
the single bubble diagram, vertex corrections are calculated from an asymptotic
expression for the two-particle vertex. A mean-field approximation for the
dc-conductivity containing the leading high-dimensional vertex corrections is
proposed which is free of spurious non-analyticities, i.e. the conductivity is
non-negative and shows no unphysical behavior in $d\geq 3$.

</DOC>
<DOC>
<DOCNO> 102171 </DOCNO>
On the relation of the monomial group with other algebraic structures


  It is shown in what way monomial group connects Abelian group Z^{n} and total
linear group GL(n). It is shown that any subgroup of Abelian group Z^{n}
induces subgroup of monomial group $S_{2}\wr S_n}$, which in its turn induces
corresponding subgroup of GL_{n}(R).

</DOC>
<DOC>
<DOCNO> 68908 </DOCNO>
R-Parity Violation and the Decay b to s gamma


  We investigate the influence of the R-parity violating couplings lambda,
lambda' and lambda'' on the branching ratio of b to s gamma in leading
logarithmic approximation. The operator basis is enlarged and the corresponding
gamma-matrix calculated. The matching conditions receive new contributions from
the R-parity violating sector. The comparison with the experiment is rather
difficult due to the model dependence of the result.

</DOC>
<DOC>
<DOCNO> 100907 </DOCNO>
Palais-Smale Condition, Index Pairs and Critical Point Theory


  This paper is concerned with index pairs in the sense of Conley index theory
for flows relative to pseudo-gradient vector fields for $C^1$-functions
satisfying Palais-Smale condition. We prove a deformation theorem for such
index pairs to obtain a Lusternik-Schnirelmann type result in Conley index
theory.

</DOC>
<DOC>
<DOCNO> 9123 </DOCNO>
Metallic Spin Glass in Infinite Dimensions


  We have combined the dynamical mean field theories of the Mott transition and
the spin glass in infinite dimensions and derived a metallic spin-glass state
from a random spin-fermion model.

</DOC>
<DOC>
<DOCNO> 8942 </DOCNO>
Spontaneous deformation of the Fermi surface due to strong correlation


  Fermi surface of the two-dimensional t-J model is studied using the
variational Monte Carlo method. We study the Gutzwiller projected d-wave
superconducting state with an additional variational parameter t'_v
corresponding to the next-nearest neighbor hopping term. It is found that the
finite t'_v<0 gives the lowest variational energy in the wide range of
hole-doping rates. The obtained momentum distribution function shows that the
Fermi surface deforms spontaneously. It is also shown that the van Hove
singularity is always located very close to the Fermi energy. Using the
Gutzwiller approximation, we show that this spontaneous deformation is due to
the Gutzwiller projection operator or the strong correlation.

</DOC>
<DOC>
<DOCNO> 117523 </DOCNO>
A large high-energy gamma-ray flare from the blazar 3C 273


  The Compton Gamma-Ray Observatory (CGRO) experiments EGRET and COMPTEL
observed the Virgo sky region continuously for 7 weeks between December 10,
1996 and January 28, 1997. The prominent quasar 3C~273 was found to be the
brightest source in gamma-rays and was significantly detected by EGRET and
COMPTEL. The EGRET experiment observed a time-variable flux at energies above
100 MeV, which reached in a 2-week flaring period (December 30, 1996 to January
14, 1997) its highest flux level observed during the CGRO-era. COMPTEL,
however, does not observe obvious time variability at energies below ~30 MeV
contemporaneous to EGRET. In particular, no flare was observed, indicating that
this outburst is solely a high-energy (>100 MeV) phenomenon. The energy
spectrum between 3 MeV and 10 GeV is well represented by a simple power-law
model. Below 3 MeV a spectral turnover is indicated. Performing spectral
analysis for different time periods, we found evidence for a spectral hardening
during the flaring period, which is consistent with the flare occurring mainly
at the higher energies and with its absence at COMPTEL energies of a few MeV.
This may be interpreted as an indication that the emission in the EGRET energy
range is dominated by a different radiation mechanism than the MeV emission. We
argue that the most likely mechanism for the high-energy flare is
inverse-Compton scattering of reprocessed accretion-disk radiation.

</DOC>
<DOC>
<DOCNO> 7668 </DOCNO>
Near-Field Microwave Microscopy of Materials Properties


  Near-field microwave microscopy has created the opportunity for a new class
of electrodynamics experiments of materials. Freed from the constraints of
traditional microwave optics, experiments can be carried out at high spatial
resolution over a broad frequency range. In addition, the measurements can be
done quantitatively so that images of microwave materials properties can be
created. We review the five major types of near-field microwave microscopes and
discuss our own form of microscopy in detail. Quantitative images of microwave
sheet resistance, dielectric constant, and dielectric tunability are presented
and discussed. Future prospects for near-field measurements of microwave
electrodynamic properties are also presented.

</DOC>
<DOC>
<DOCNO> 101678 </DOCNO>
The failure of the uncountable non-commutative Specker Phenomenon


  Higman proved in 1952 that every free group is non-commutatively slender,
this is to say that if G is a free group and h is a homomorphism from the
countable complete free product (X_omega Z) to G, then there exists a finite
subset F of omega and a homomorphism h:*_{i in F} Z --> G such that h=h rho_F,
where rho_F is the natural map from (X_{i in omega})Z to *_{i in F}Z .
Corresponding to the abelian case this phenomenon was called the
non-commutative Specker Phenomenon. In this paper we show that Higman's result
fails if one passes from countable to uncountable. In particular, we show that
for non-trivial groups G_alpha (alpha in lambda) and uncountable cardinal
lambda there are 2^{2^lambda} homomorphisms from the complete free product of
the G_alpha 's to the ring of integers.

</DOC>
<DOC>
<DOCNO> 84671 </DOCNO>
DC Cancellation As a Method of Generating a t^2 Response and of Solving


  This paper solves two major problems which have blocked a free-fall
Equivalence-Principle (EP) in a satellite for 25 years: a semimajor-axis error
between the two proof masses cannot be distinguished from an EP violation and
the response to an EP violation only grows as t not t^2. Using the cancellation
method described in this paper, the nonobservability problem can be suppressed
and a t^2 response can be generated which lasts between 10^4 and 10^6 seconds
depending on the cancellation accuracy. t^2 response times between 10^5 and
10^6 seconds are equivalent to a very tall (0.1 to 10 AU) drop tower with a
constant gravitational field of 3/7 ge.

</DOC>
<DOC>
<DOCNO> 151779 </DOCNO>
Supersymmetric Noether Currents and Seiberg-Witten Theory


  The purpose of this paper is twofold. The first purpose is to review a
systematic construction of Noether currents for supersymmetric theories,
especially effective supersymmetric theories. The second purpose is to use
these currents to derive the mass-formula for the quantized Seiberg-Witten
model from the supersymmetric algebra. We check that the mass-formula of the
low-energy theory agrees with that of the full theory (in the broken phase).

</DOC>
<DOC>
<DOCNO> 84407 </DOCNO>
A nongravitational wormhole


  Using the effective metric formalism for photons in a nonlinear
electromagnetic theory, we show that a certain field configuration in
Born-Infeld electromagnetism in flat spacetime can be interpreted as an
ultrastatic spherically symmetric wormhole. We also discuss some properties of
the effective metric that are valid for any field configuration.

</DOC>
<DOC>
<DOCNO> 10447 </DOCNO>
Equipartition and Virial theorems in a nonextensive optimal Lagrange


  We revisit some topics of classical thermostatistics from the perspective of
the nonextensive optimal Lagrange multipliers (OLM), a recently introduced
technique for dealing with the maximization of Tsallis' information measure. It
is shown that Equipartition and Virial theorems can be reproduced by Tsallis'
nonextensive formalism independently of the value of the nonextensivity index.

</DOC>
<DOC>
<DOCNO> 120241 </DOCNO>
Fragmentation and Star Formation in Turbulent Cores


  We examine the conditions under which binary and multiple stars may form out
of turbulent molecular cloud cores using high resolution 3-D, adaptive mesh
refinement (AMR) hydrodynamics (Truelove et al., 1997, 1998; Klein, 1999). We
argue that previous conclusions on the conditions for cloud fragmentation have
limited applicability, since they did not allow for the nonlinear density and
velocity perturbations that are ubiquitous in molecular cloud cores. Over the
past year, we have begun to simulate the evolution of marginally stable,
turbulent cores. These models have radii, masses, density contrasts, turbulent
linewidths, and projected velocity gradients consistent with observations of
low-mass molecular cloud cores. Our models are evolved in time under
self-gravitational hydrodynamics with AMR using a barotropic equation of state
that models the transition from an isothermal to an adiabatic equation of
state. We examine several properties of the resulting protostellar fragments
and discuss the qualitative nature of the fragmentation process in realistic
cloud cores: the transition from single to binary and multiple stars; the
formation of misaligned binary systems; and the role played by filament
formation in the formation of stars.

</DOC>
<DOC>
<DOCNO> 118859 </DOCNO>
Interferometric measurement of resonance transition wavelengths in C IV,


  We have made the first interferomeric measurements of the wavelengths of the
important ultraviolet diagnostic lines in the spectra \ion{C}{4} near 155 nm
and \ion{Si}{4} near 139 nm with a vacuum ultraviolet Fourier transform
spectrometer and high-current discharge sources. The wavelength uncertainties
were reduced by one order of magnitude for the \ion{C}{4} lines and by two
orders of magnitude for the \ion{Si}{4} lines. Our measurements also provide
accurate wavelengths for resonance transitions in \ion{Al}{3}, \ion{Al}{2}, and
\ion{Si}{2}.

</DOC>
<DOC>
<DOCNO> 10293 </DOCNO>
Crystal-field interactions in PrRu2Si2


  Ferromagnetic compound PrRu2Si2 exhibits a giant magnetocrystalline
anisotropy of about 400 T. Its ordered moment below Tc=14K reaches 2.7 mB and
is parallel to [0 0 1] crystalline direction. We have attributed the magnetism
of PrRu2S2 to the Pr ions and performed calculations of the fine electronic
structure of the Pr ion in the tetragonal symmetry, relevant to PrRu2Si2 taking
into account crystal-field and inter-site, spin-dependent exchange
interactions. Spin-dependent interactions have been taken into account by means
of molecular-field approximation. The derived energy level scheme is associated
with the removal of the degeneracy of the lowest multiplet given by Hund's
rules, 3H4. Magnetic and electronic properties resulting from this fine
structure are compared with all known experimental results. Our calculations
reproduce well the zero-temperature moment, temperature dependence of the
magnetic susceptibility, single-crystalline magnetization curves with the
anisotropy field of 400T, the specific heat with the sharp peak at Tc as well
as inelastic-neutron-scattering data.

</DOC>
<DOC>
<DOCNO> 100263 </DOCNO>
On the obstruction to the exactness of the variational bicomplex


  We study the obstruction to the exactness of the variational complex for a
field theory on an affine bundle.

</DOC>
<DOC>
<DOCNO> 12059 </DOCNO>
Spintronics and Quantum Computing with Quantum Dots


  The creation, coherent manipulation, and measurement of spins in
nanostructures open up completely new possibilities for electronics and
information processing, among them quantum computing and quantum communication.
We review our theoretical proposal for using electron spins in quantum dots as
quantum bits. We present single- and two qubit gate mechanisms in laterally as
well as vertically coupled quantum dots and discuss the possibility to couple
spins in quantum dots via superexchange. We further present the recently
proposed schemes for using a single quantum dot as spin-filter and spin
read-out/memory device.

</DOC>
<DOC>
<DOCNO> 13597 </DOCNO>
Marginal Fermi liquid resonance induced by a quantum magnetic impurity


  We consider a model of an Anderson impurity embedded in a $d_{x^2-y^2}$-wave
superconducting state to describe the low-energy excitations of cuprate
superconductors doped with a small amount of magnetic impurities. Due to the
Dirac-like energy dispersion, a sharp localized resonance above the Fermi
energy, showing a marginal Fermi liquid behavior ($\omega \ln \omega$ as
$\omega \to 0$) is predicted for the impurity states. The same logarithmic
dependence of self-energy and a linear frequency dependence of the relaxation
rate are also derived for the conduction electrons, characterizing a new
universality class for the strong coupling fixed point. At the resonant
energies, the spatial distribution of the electron density of states around the
magnetic impurity is calculated, to be confronted with measurements of the
scanning tunneling microscopy on Bi$_2$Sr$_2$Ca(Cu$_{1-x}$Ni$_x$)O$_{8+\delta
}$.

</DOC>
<DOC>
<DOCNO> 117352 </DOCNO>
Is Thermal Instability Significant in Turbulent Galactic Gas?


  We investigate numerically the role of thermal instability (TI) as a
generator of density structures in the interstellar medium (ISM), both by
itself and in the context of a globally turbulent medium. Simulations of the
instability alone show that the condenstion process which forms a dense phase
(``clouds'') is highly dynamical, and that the boundaries of the clouds are
accretion shocks, rather than static density discontinuities. The density
histograms (PDFs) of these runs exhibit either bimodal shapes or a single peak
at low densities plus a slope change at high densities. Final static situations
may be established, but the equilibrium is very fragile: small density
fluctuations in the warm phase require large variations in the density of the
cold phase, probably inducing shocks into the clouds. This result suggests that
such configurations are highly unlikely. Simulations including turbulent
forcing show that large- scale forcing is incapable of erasing the signature of
the TI in the density PDFs, but small-scale, stellar-like forcing causes
erasure of the signature of the instability. However, these simulations do not
reach stationary regimes, TI driving an ever-increasing star formation rate.
Simulations including magnetic fields, self-gravity and the Coriolis force show
no significant difference between the PDFs of stable and unstable cases, and
reach stationary regimes, suggesting that the combination of the stellar
forcing and the extra effective pressure provided by the magnetic field and the
Coriolis force overwhelm TI as a density-structure generator in the ISM. We
emphasize that a multi-modal temperature PDF is not necessarily an indication
of a multi-phase medium, which must contain clearly distinct thermal
equilibrium phases.

</DOC>
<DOC>
<DOCNO> 72033 </DOCNO>
Lepton-Flavour Violation in Vector Boson Decays


  This paper is subsumed and superseded by hep-ph/0111175.

</DOC>
<DOC>
<DOCNO> 8103 </DOCNO>
Correlations in doped Antiferromagnets


  A comprehensive study of doped RVB states is performed. It reveals a
fundamental connection between superconductivity and quantum spin fluctuations
in underdoped cuprates :
 {\em Cooper pair hopping} strongly reduces the local magnetization $m_0$. This
effect pertains to recent muon spin rotation measurements in which $m_0$ varies
weakly with hole doping in the poorly conducting regime, but drops
precipitously above the onset of superconductivity. Gutzwiller mean field
Approximation (GA) is found to agree with numerical Monte Carlo calculation. GA
shows for example that for a bond amplitude $u(r)=e^{-r/\xi}$, spin spin
correlations decay exponentially with a correlation length $\propto e^{3\pi
\xi^2/2}$. Expectation value of the Heisenberg model is found to be correlated
with average loop density.

</DOC>
<DOC>
<DOCNO> 84596 </DOCNO>
A gentle introduction to the foundations of classical electrodynamics:


  The axiomatic structure of the electromagnetic theory is outlined. We will
base classical electrodynamics on (1) electric charge conservation, (2) the
Lorentz force, (3) magnetic flux conservation, and (4) on the Maxwell-Lorentz
spacetime relations. This yields the Maxwell equations. The consequences will
be drawn, inter alia, for the interpretation and the dimension of the electric
and magnetic fields.

</DOC>
<DOC>
<DOCNO> 68460 </DOCNO>
Event-by-event physics in relativistic heavy ion collisions


  Motivated by forthcoming experiments at RHIC and LHC, and results from SPS, a
review is given of the present state of event-by-event fluctuations in
ultrarelativistic heavy-ion collisions. Fluctuations in particle
multiplicities, ratios, transverse momenta, rapidity, etc. are calculated in
participant nucleon as well as thermal models. The physical observables,
including multiplicity, kaon to pion ratios, and transverse momenta agree well
with recent NA49 data at the SPS, and indicate that such studies do not yet
reveal the presence of new physics. Predictions for RHIC and LHC energies are
given. The centrality dependence with and without a phase transition to a
quark-gluon plasma is discussed - in particular, how the physical quantities
are expected to display a qualitative different behavior in case of a phase
transition, and can be signaled by anomalous fluctuations and correlations in a
number of observables.

</DOC>
<DOC>
<DOCNO> 11873 </DOCNO>
Eight-potential-well order-disorder ferroelectric model and effects of


  An eight-potential-well order-disorder ferroelectric model was presented and
the phase transition was studied under the mean-field approximation. It was
shown that the two-body interactions are able to account for the first-order
and the second order phase transitions. With increasing the random fields in
the system, a first-order phase transition is transformed into a second-order
phase transition, and furthermore, a second-order phase transition is
inhibited.
  However, proper random fields can promote the spontaneous appearance of a
first-order phase transition by increasing the overcooled temperature. The
connections of the model with relaxors were discussed.

</DOC>
<DOC>
<DOCNO> 80852 </DOCNO>
Perfect Gauge Actions on Anisotropic Lattices


  On anisotropic lattices, where generally the lattice is rather coarse in
spatial directions, a parametrized classically perfect action could help
reducing lattice artifacts considerably. We investigate the possibility of
constructing such actions for SU(3) gauge theory. We present two different
methods to do so, either repeating the procedure used to create our newly
parametrized isotropic FP action, or performing one single step starting with
the isotropic result. The anisotropic action is parametrized using an ansatz
including anisotropically APE-like smeared (``fat'') links. The parametrized
classically perfect action with anisotropy $\xi=a_s/a_t=2$ is constructed and
the renormalized anisotropy is measured using the torelon dispersion relation.
It turns out that the renormalization is small.

</DOC>
<DOC>
<DOCNO> 68237 </DOCNO>
Substructure of the Nucleon in the Chiral Quark Model


  The spin and orbital angular momentum carried by different quark flavors in
the nucleon are calculated in the SU(3) chiral quark model with
symmetry-breaking. The similar calculation is also performed for other octet
and decuplet baryons. Furthermore, the flavor and spin contents for charm and
anti-charm quarks are predicted in the SU(4) symmetry breaking chiral quark
model.

</DOC>
<DOC>
<DOCNO> 11880 </DOCNO>
Electronic states in a quantum lens


  We present a model to find analytically the electronic states in
self-assembled quantum dots with a truncated spherical cap (`lens') geometry. A
conformal analytical image is designed to map the quantum dot boundary into a
dot with semi-spherical shape. The Hamiltonian for a carrier confined in the
quantum lens is correspondingly mapped into an equivalent operator and its
eigenvalues and eigenfunctions for the corresponding Dirichlet problem are
analyzed. A modified Rayleigh-Schr\"{o}dinger perturbation theory is presented
to obtain analytical expressions for the energy levels and wavefunctions as a
function of the spherical cap height $b$ and radius $a$ of the circular cross
section. Calculations for a hard wall confinement potential are presented, and
the effect of decreasing symmetry on the energy values and eigenfunctions of
the lens-shape quantum dot is studied. As the degeneracies of a semi-circular
geometry are broken for $b\neq a$, our perturbation approach allows tracking of
the split states. Energy states and electronic wavefunctions with $m=0$ present
the most pronounced influence on the reduction of the lens height. The
analytical expressions presented here can be used to better parameterize the
states in realistic self-assembled quantum dots.

</DOC>
<DOC>
<DOCNO> 101240 </DOCNO>
Operational resolutions and state transitions in a categorical setting


  We define a category with as objects operational resolutions and with as
morphisms - not necessarily deterministic - state transitions. We study
connections with closure spaces and join-complete lattices and sketch physical
applications related to evolution and compoundness. An appendix with
preliminaries on quantaloids is included.

</DOC>
<DOC>
<DOCNO> 70772 </DOCNO>
eps'/eps in the standard model


  I discuss the estimate of the CP-violating ratio eps'/eps by stressing the
role played by the chiral quark model in predicting the experiment and in
showing that the same dynamical mechanism at work in the Delta I=1/2 rule also
explains the larger value obtained for eps'/eps in this model with respect to
other estimates.

</DOC>
<DOC>
<DOCNO> 121019 </DOCNO>
Ionization, Magneto-rotational, and Gravitational Instabilities in Thin


  We consider the combined role of the thermal ionization, magneto-rotational
and gravitational instabilities in thin accretion disks around supermassive
black holes. We find that in the portions of the disk unstable to the
ionization instability, the gas remains well coupled to the magnetic field even
on the cold, neutral branch of the thermal limit cycle. This suggests that the
ionization instability is not a significant source of large amplitude
time-dependent accretion in AGN. We also argue that, for accretion rates
greater than 10^{-2} solar masses per year, the gravitationally unstable and
magneto-rotationally unstable regions of the accretion disk overlap; for lower
accretion rates they may not. Some low-luminosity AGN, e.g. NGC 4258, may thus
be in a transient phase in which mass is building up in a non-accreting
gravitationally and magneto-rotationally stable ``dead zone.'' We comment on
possible implications of these findings.

</DOC>
<DOC>
<DOCNO> 169857 </DOCNO>
Propagation of entangled light pulses through dispersive and absorbing


  The modification of initially entangled light pulses passing through
dispersive and absorbing four-port devices is studied, using recently obtained
results on quantum state transformations [Phys. Rev. A 59, 4716 (1999)]. The
fidelity and indices of quantum correlations based on the von Neumann entropy
are calculated. Their dependence on both the pulse shape and the four-port
device parameters is studied. It is shown, that due to dispersion and
absorption the quantum correlations are reduced substantially for large initial
entanglement.

</DOC>
<DOC>
<DOCNO> 122593 </DOCNO>
The Distribution of Dark Matter in Galaxies: Constant-Density Dark Halos


  In this paper we review the main and the most recent evidence for the
presence of a core radius in the distribution of the dark matter around spiral
galaxies. Their rotation curves, coadded according to the galaxy luminosity,
conform to an Universal profile which can be represented as the sum of an
exponential thin disk term plus a spherical halo term with a flat density core.
  From dwarfs to giants, these halos feature a constant density region of size
r_0 and core density rho_0 related by rho_0= 4.5 10^{-2} (r_0/kpc)^{-2/3}M_sol
pc^{-3}. At the highest masses rho_0 decreases exponentially, with r_0
revealing a lack of objects with disk masses > 10^{11}M_sol and central
densities > 1.5 10^{-2}(r_0/kpc)^{-3} M_sol pc^{-3}, which implies a maximum
mass of ~2 10^{12} M_sol for halos hosting spirals. The fine structure of dark
matter halos is obtained from the kinematics of a number of suitable
low-luminosity disk galaxies. The inferred halo circular velocity increases
linearly with radius out to the edge of the stellar disk, implying a constant
dark halo density over the entire disk region. The structural properties of
halos around normal spirals are similar to those around dwarf and low surface
brightness galaxies; nevertheless they provide far more substantial evidence of
the discrepancy between the mass distributions predicted in the Cold Dark
Matter scenario and those actually detected around galaxies.

</DOC>
<DOC>
<DOCNO> 39748 </DOCNO>
A Status Report of KLOE at DAFNE


  The major goal of the KLOE experiment is to measure Re(epsilon' /epsilon) in
the kkbar system, with a precision of 10^{-4},both via the traditional double
ratio method and quantum interferometry. The experiment has started taking data
at DAFNE, the phi-factory built at the Frascati National Laboratory (LNF) of
INFN in Italy, beginning in April 1999. In the early phase of the commissioning
(before KLOE roll-in), DAFNE has achieved multi bunch luminosities of 10^{31}
cm^{-2} s^{-1} with 13 bunches and 200 mA. Detailed studies are presently
underway to compensate for the large perturbation brought in by the KLOE
solenoid, which has caused a drastic decrease of the peak luminosity.
Nevertheless the first collected data, corresponding to an integral luminosity
of 220 nb^{-1}, show that KLOE is performing to the design specifications in
all its hardware and software components.

</DOC>
<DOC>
<DOCNO> 150596 </DOCNO>
Ring Division Algebras, Self-Duality and Supersymmetry


  We argue that once octonions are formulated as soft Lie algebras, they may be
safely used and the non-associativity can be overcame. The necessary points
are: (a) Fixing the direction of action by introducing the \delta operator. (b)
Closing the \delta algebra by using structure functions f_{ijk} (\phi). (c)
Representation of the \delta algebra can be developed. The E or E(\phi) can be
found and their structure functions can be computed easily. There may be
different applications of soft seven sphere in physics. We have given two cases
where the ring division algebras occupies a special position. Self-duality and
Simple supersymmetric Yang-Mills theories are two promising places where soft
seven sphere prove to be useful and essential.

</DOC>
<DOC>
<DOCNO> 120528 </DOCNO>
Spectroscopic follow up of arclets in AC114 with the VLT


  We present the first results on the VLT/FORS-1 spectroscopic survey of
amplified sources and multiple images in the lensing cluster AC114. Background
sources were selected in the cluster core, close to the critical lines, using
photometric redshifts combined with lensing inversion criteria. Spectroscopic
results are given, together with a brief summary of the properties of some of
these high-z galaxies.

</DOC>
<DOC>
<DOCNO> 7974 </DOCNO>
The jamming transition of Granular Media


  We briefly review the basics ideas and results of a recently proposed
statistical mechanical approach to granular materials. Using lattice models
from standard Statistical Mechanics and results from a mean field replica
approach and Monte Carlo simulations we find a jamming transition in granular
media closely related to the glass transition in super-cooled liquids. These
models reproduce the logarithmic relaxation in granular compaction and
reversible-irreversible lines, in agreement with experimental data. The models
also exhibit aging effects and breakdown of the usual fluctuation dissipation
relation. It is shown that the glass transition may be responsible for the
logarithmic relaxation and may be related to the cooperative effects underlying
many phenomena of granular materials such as the Reynolds transition.

</DOC>
<DOC>
<DOCNO> 152318 </DOCNO>
Renormalization of noncommutative U(N) gauge theories


  We give an explicit proof that the noncommutative U(N) gauge theories are
one-loop renormalizable

</DOC>
<DOC>
<DOCNO> 8079 </DOCNO>
Counting Statistics of an Adiabatic Pump


  We consider quantum statistics of charge transmitted through a mesoscopic
device in the adiabatic pumping process. A general formula for the distribution
function of the transmitted charge in terms of the time-dependent S-matrix is
obtained. It is applied to a few simple examples of the pumping cycles. We
identify coherent pumping strategies which lead to the binomial charge
distribution and minimize the fluctuations of the pumped current. Conditions
for the ideal noiseless quantized pump are discussed.

</DOC>
<DOC>
<DOCNO> 99645 </DOCNO>
Asymptotic density and the asymptotics of partition functions


  Let A be a set of positive integers with gcd(A) = 1, and let p_A(n) be the
partition function of A. Let c = \pi \sqrt(2/3). Let \alpha > 0. It is proved
that log p_A(n) ~ c\sqrt(\alpha n) if and only if the set A has asymptotic
density \alpha.

</DOC>
<DOC>
<DOCNO> 119482 </DOCNO>
On the bolometric quiescent luminosity and luminosity swing of black


  Low mass X-ray transients (LMXRTs) hosting black hole candidates (BHCs)
display on average a factor of ~100 larger swing in the minimum (quiescent) to
maximum (outburst) X-ray luminosity than neutron stars (NSs), despite the fact
that the swing in the mass inflow rate is likely in the same range. Advection
dominated accretion flows (ADAFs) were proposed to interpret such a difference.
The residual optical/UV emission of quiescent LMXRTs, after subtraction of the
companion star spectrum, is produced by synchrotron radiation in the (latest
version) of ADAF and therefore is part of the ADAF's luminosity budget. We
demonstrate that, once the residual optical/UV emission is taken into account,
the bolometric luminosity swing of BHCs is consistent with that of NSs. We
explore here an alternative scenario to ADAFs in which very little mass
accretion onto the collapsed star takes place in the quiescence intervals. The
residual optical/UV emission of BHCs are expected to derive from the energy
released by the matter transferred from the companion star at radii comparable
to the circularisation radius. The quiescent X-ray luminosity originates either
from accretion onto the BH at very low rates and/or from coronal activity in
the companion star or in the outer disk. For comparably small mass inflow
rates, the NSs in these systems are likely in the radio pulsar regime. In the
interaction of the radio pulsar relativistic wind with matter transferred from
the companion star, a shock forms, the power law-like emission of which powers
both the harder X-ray emission and most of the residual optical/UV. The soft,
thermal-like X-ray component may arise from the cooling of the NS surface. This
scenario matches well both the X-ray and bolometric luminosity swing of LMXRTs.
(ABRIDGED).

</DOC>
<DOC>
<DOCNO> 71795 </DOCNO>
Models for the Polarized Parton Distributions of the Nucleon


  Polarized deep inelastic scattering (DIS) data are analyzed in leading and
next-to-leading order of QCD within the common `standard' scenario of polarized
parton distributions with a flavor-symmetric light sea (antiquark) distribution
$\delta\bar{q}$, and a completely SU(3)$_f$ broken `valence' scenario with
totally flavor-asymmetric light sea densities
$(\delta\bar{u}\neq\delta\bar{d}\neq\delta\bar{s})$. The latter flavor-broken
light sea distributions are modelled with the help of a Pauli-blocking ansatz
at the low radiative/dynamical input scales of $\mu_{\rm LO(NLO)}^2=0.26$
(0.40) GeV$^2$ which complies with predictions of the chiral quark-soliton
model and expectations based on the statistical parton model as well as with
the corresponding, well established, flavor-broken unpolarized sea
($\bar{d}>\bar{u}$). Present semi-inclusive DIS data cannot yet uniquely
discriminate between those two flavor-symmetric and flavor-broken polarized
light sea scenarios.

</DOC>
<DOC>
<DOCNO> 151577 </DOCNO>
Fractional and Integer Charges from Levinson's Theorem


  We compute fractional and integer fermion quantum numbers of static
background field configurations using phase shifts and Levinson's theorem. By
extending fermionic scattering theory to arbitrary dimensions, we implement
dimensional regularization in a 1+1 dimensional gauge theory. We demonstrate
that this regularization procedure automatically eliminates the anomaly in the
vector current that a naive regulator would produce. We also apply these
techniques to bag models in one and three dimensions.

</DOC>
<DOC>
<DOCNO> 69912 </DOCNO>
How Large are Dissipative Effects in Non-Critical Liouville String


  In the context of non-critical Liouville strings, we clarify why we expect
non-quantum-mechanical dissipative effects to be of order E^2/M_P, where E is a
typical energy scale of the probe, and M_P is the Planck scale. In Liouville
strings, energy is conserved {\it at best} only as a statistical average, as
distinct from Lindblad systems, where it is {\it strictly} conserved at an
operator level, and the magnitude of dissipative effects could only be much
smaller. We also emphasize the importance of nonlinear terms in the evolution
equation for the density matrix, which are important for any analysis of
complete positivity.

</DOC>
<DOC>
<DOCNO> 121643 </DOCNO>
A molecular shell with star formation toward the supernova remnant


  A field of ~38'x38' around the supernova remnant (SNR) G349.7+0.2 has been
surveyed in the CO J=1-0 transition with the 12 Meter Telescope of the NRAO,
using the On-The-Fly technique. The resolution of the observations is 54". We
have found that this remnant is interacting with a small CO cloud which, in
turn, is part of a much larger molecular complex, which we call the ``Large CO
Shell''. The Large CO Shell has a diameter of about 100 pc, an H_2 mass of
930,000 solar masses, and a density of 35 cm-3. We investigate the origin of
this structure and suggest that an old supernova explosion ocurred about 4
million years ago, as a suitable hypothesis. Analyzing the interaction between
G349.7+0.2 and the Large CO Shell, it is possible to determine that the shock
front currently driven into the molecular gas is a non-dissociative shock
(C-type), in agreement with the presence of OH 1720 MHz masers. The positional
and kinematical coincidence among one of the CO clouds that constitute the
Large CO Shell, an IRAS point-like source and an ultracompact H II region,
indicate the presence of a recently formed star. We suggest that the formation
of this star was triggered during the expansion of the Large CO Shell, and
suggest the possibility that the same expansion also created the progenitor
star of G349.7+0.2. The Large CO Shell would then be one of the few
observational examples of supernova-induced star formation.

</DOC>
<DOC>
<DOCNO> 178394 </DOCNO>
Effects of the secondary decays on the isotopic thermometers


  The sharp microcanonical multifragmentation model from [Al. H. Raduta and Ad.
R. Raduta, Phys. Rev. C 55, 1344 (1997); Phys. Rev. C, in press] is employed
for evaluating the nuclear caloric curve predictions of nine isotopic
thermometers for three representative nuclei. Evaluations are performed for
both primary decay and asymptotic stages. Effects of the secondary decays on
the primary decay caloric curves are evidenced and discussed. In both cases a
dispersive character of the isotopic caloric curves with increasing the source
excitation energy is observed. A procedure of calibrating the isotopic
thermometers on the microcanonical predictions for both primary decay and
asymptotic stages is proposed. The resulting set of calibrating parameters for
each thermometer is independent on the source size, on its excitation energy
and, in the case of the primary decay, on the freeze-out radius assumption.

</DOC>
<DOC>
<DOCNO> 12480 </DOCNO>
Finite temperature dynamic structure function of the free Bose gas


  A detailed calculation of the finite temperature dynamic structure function
of the free Bose gas is presented and discussed. After a short derivation of
the expressions describing the exact response $S(q,\omega;T)$ and the Impulse
Approximation (IA) $S_{IA}(q,\omega;t)$, their main properties and their
evolution with q and T are analyzed. The lowest order energy weighted sum rules
of both $S(q,\omega;T)$ and $S_{IA}(q,\omega;T)$ are also derived and
commented. Finally, the $q\to\infty$ asymptotic behavior is analyzed and
discussed in terms of scaling laws.

</DOC>
<DOC>
<DOCNO> 121978 </DOCNO>
Water Abundance in Molecular Cloud Cores


  We present Submillimeter Wave Astronomy Satellite (SWAS) observations of the
1_{10}-1_{01} transition of ortho-water at 557 GHz toward 12 molecular cloud
cores. The water emission was detected in NGC 7538, Rho Oph A, NGC 2024, CRL
2591, W3, W3(OH), Mon R2, and W33, and was not detected in TMC-1, L134N, and
B335. We also present a small map of the water emission in S140. Observations
of the H_2^{18}O line were obtained toward S140 and NGC 7538, but no emission
was detected. The abundance of ortho-water relative to H_2 in the giant
molecular cloud cores was found to vary between 6x10^{-10} and 1x10^{-8}. Five
of the cloud cores in our sample have previous water detections; however, in
all cases the emission is thought to arise from hot cores with small angular
extents. The water abundance estimated for the hot core gas is at least 100
times larger than in the gas probed by SWAS. The most stringent upper limit on
the ortho-water abundance in dark clouds is provided in TMC-1, where the
3-sigma upper limit on the ortho-water fractional abundance is 7x10^{-8}.

</DOC>
<DOC>
<DOCNO> 7855 </DOCNO>
Monte Carlo computation of correlation times of independent relaxation


  We investigate aspects of universality of Glauber critical dynamics in two
dimensions. We compute the critical exponent $z$ and numerically corroborate
its universality for three different models in the static Ising universality
class and for five independent relaxation modes. We also present evidence for
universality of amplitude ratios, which shows that, as far as dynamic behavior
is concerned, each model in a given universality class is characterized by a
single non-universal metric factor which determines the overall time scale.
This paper also discusses in detail the variational and projection methods that
are used to compute relaxation times with high accuracy.

</DOC>
<DOC>
<DOCNO> 120261 </DOCNO>
Gravitational Lens Statistics for Generalized NFW Profiles: Parameter


  Strong lensing is a powerful probe of the distribution of matter in the cores
of clusters of galaxies. Recent studies suggest that the cold dark matter model
predicts cores that are denser than those observed in galaxies, groups and
clusters. One possible resolution of the discrepancy is that the dark matter
has strong interactions (SIDM), which leads to lower central densities. A
generalized form of the Navarro, Frenk and White profile (Zhao profile) may be
used to describe these halos. In this paper we examine gravitational lensing
statistics for this class of model. The optical depth to multiple imaging is a
very sensitive function of the profile parameters in the range of interest for
SIDM halos around clusters of galaxies. Less concentrated profiles, which
result from larger self-interaction cross-sections, can produce many fewer
lensed pairs. Lensing statistics provide a powerful test for SIDM. More
realistic and observationally oriented calculations remain to be done, however
larger self-interaction cross-sections may well be ruled out by the very
existence of strong lenses on galaxy cluster scales. The inclusion of centrally
dominant cluster galaxies should boost the cross-section to multiple imaging.
However our preliminary calculations suggest that the additional multiple
imaging rate is small with respect to the differences in multiple imaging rate
for different halo profiles. In future statistical studies, it will be
important to properly account for the scatter among halo profiles since the
optical depth to multiple imaging is dominated by the most concentrated members
of a cluster population.

</DOC>
<DOC>
<DOCNO> 9971 </DOCNO>
Band and filling controlled transitions in exactly solved electronic


  We describe a general method to study the ground state phase diagram of
electronic models on chains whose extended Hubbard hamiltonian is formed by a
generalized permutator plus a band-controlling term. The method, based on the
appropriate interpretation of Sutherland's species, yields under described
conditions a reduction of the effective Hilbert space. In particular, we derive
the phase diagrams of two new models; the first one exhibits a band-controlled
insulator-superconductor transition at half-filling for the unusually high
value $U_c=6 t$; the second one is characterized by a filling-controlled
metal-insulator transition between two finite regions of the diagram.

</DOC>
<DOC>
<DOCNO> 11146 </DOCNO>
Charge Ordering and Spin Dynamics in NaV2O5


  We report high-resolution neutron inelastic scattering experiments on the
spin excitations of NaV2O5. Below Tc, two branches associated with distinct
energy gaps are identified. From the dispersion and intensity of the spin
excitation modes, we deduce the precise zig-zag charge distribution on the
ladder rungs and the corresponding charge order (about 0.6). We argue that the
spin gaps observed in the low-T phase of this compound are primarily due to the
charge transfer.

</DOC>
<DOC>
<DOCNO> 80848 </DOCNO>
SUSY Ward identities in N=1 SYM theory on the lattice


  The SUSY Ward identities (WIs) for the N=1 SU(2) SUSY Yang Mills theory
discretized on the lattice with Wilson fermions (gluinos) are considered. The
study is performed in the framework of a Monte Carlo simulation of the model
with light dynamical gluinos. The renormalization and mixing constants of the
lattice SUSY current $Z_S$ and $Z_T$ and the additively renormalized gluino
mass $m_S$ are unknown parameters of the SUSY WIs. Using suitable on-shell
combinations of the WIs, the ratios $Z_T/Z_S$ and $m_S/Z_S$ are determined
non-perturbatively at one value of the coupling constant $g_0$ and two values
of the hopping parameter $\kappa$.

</DOC>
<DOC>
<DOCNO> 99295 </DOCNO>
Continuous images of sets of reals


  We will show that, consistently, every uncountable set can be continuously
mapped onto a non measure zero set, while there exists an uncountable set whose
all continuous images into a Polish space are meager.

</DOC>
<DOC>
<DOCNO> 70889 </DOCNO>
Supersymmetric Microscopic Theory of the Standard Model


  We promote the microscopic theory of standard model (MSM, hep-ph/0007077)
into supersymmetric framework in order to solve its technical aspects of vacuum
zero point energy and hierarchy problems, and attempt, further, to develop its
realistic viable minimal SUSY extension. Among other things that - the MSM
provides a natural unification of geometry and the field theory, has clarified
the physical conditions in which the geometry and particles come into being, in
microscopic sense enables an insight to key problems of particle phenomenology
and answers to some of its nagging questions - a present approach also leads to
quite a new realization of the SUSY yielding a physically realistic particle
spectrum. It stems from the special subquark algebra, from which the nilpotent
supercharge operators are derived. The resulting theory makes plausible
following testable implications for the current experiments at LEP2, at the
Tevatron and at LHC drastically different from those of the conventional MSSM
models: 1. All the sparticles and Higgs bosons never could emerge in spacetime
continuum, thus, they cannot be discovered in these experiments nor at any
energy range. 2. For each of the three SM families of quarks and leptons there
are corresponding heavy family partners with the same quantum numbers lying far
above the electroweak scale, respectively, at the energy threshold values:
$E_{1}>(419.6 \pm 12.0)GeV, \quad E_{2}= (457.6 \pm 13.2)GeV$ and $E_{3}=(521.4
\pm 15.0)GeV.$

</DOC>
<DOC>
<DOCNO> 118275 </DOCNO>
A local infrared perspective to deeper ISO surveys


  We present new techniques to produce IRAS 12 micron samples of galaxies and
stars. We show that previous IRAS 12 micron samples are incompatible for
detailed comparison with ISO surveys and review their problems. We provide a
stellar infrared diagnostic diagram to distinguish galaxies from stars without
using longer wavelength IRAS colour criteria and produce complete 12 micron
samples of galaxies and stars. This new technique allows us to estimate the
contribution of non-dusty galaxies to the IRAS 12 micron counts and produce a
true local mid-infrared extragalactic sample compatible with ISO surveys. We
present our initial analysis and results.

</DOC>
<DOC>
<DOCNO> 84734 </DOCNO>
Geometric Conditions on the Type of Matter Determining the Flat Behavior


  In an arbitrary axisymmetric stationary spacetime, we determine the
expression for the tangential velocity of test objects following a circular
stable geodesic motion in the equatorial plane, as function of the metric
coeffiencients. Next, we impose the condition, observed in large samples of
disks galaxies, that the magnitude of such tangential velocity be radii
independent, obtaining a constraint equation among the metric coefficients, and
thus arriving to an iff condition: The tangential velocity of test particles is
radii independent iff the metric coefficients satisfied the mentioned
constraint equation. Furthermore, for the static case, the constraint equation
can be easily integrated, leaving the spacetime at the equatorial plane
essentially with only one independent metric coefficient. With the geometry
thus fixed, we compute the Einstein tensor and equate it to and arbitrary
stress energy tensor, in order to determined the type of energy-matter which
could produce such a geometry. Within an approximation, we deduce a constraint
equation among the components of the stress energy tensor. We test in that
constraint equation several well known types of matter, which have been
proposed as dark matter candidates and are able to point for possible right
ones.

</DOC>
<DOC>
<DOCNO> 69842 </DOCNO>
BPS Domain Walls in Models with Flat Directions


  We consider BPS domain walls in the four dimensional N=1 supersymmetric
models with continuous global symmetry. Since the BPS equation is covariant
under the global transformation, the solutions of the BPS walls also have the
global symmetry. The moduli space of the supersymmetric vacua in such models
have non-compact flat directions, and the complex BPS walls interpolating
between two disjoint flat directions can exist. We examine this possibility in
two models with global O(2) symmetry, and construct the solution of such BPS
walls.

</DOC>
<DOC>
<DOCNO> 71060 </DOCNO>
Application of Discrete Light-Cone Quantization to Yukawa Theory in Four


  The numerical technique of discrete light-cone quantization (DLCQ) is applied
to a single-fermion truncation of Yukawa theory in four dimensions. The
truncated theory is regulated by three Pauli-Villars bosons, which are
introduced directly in the DLCQ Fock-state basis. A special form of the Lanczos
diagonalization algorithm is used to handle the indefinite metric.
Renormalization is done nonperturbatively.

</DOC>
<DOC>
<DOCNO> 13011 </DOCNO>
Point-Contact Conductances from Density Correlations


  We formulate and prove an exact relation which expresses the moments of the
two-point conductance for an open disordered electron system in terms of
certain density correlators of the corresponding closed system. As an
application of the relation, we demonstrate that the typical two-point
conductance for the Chalker-Coddington model at criticality transforms like a
two-point function in conformal field theory.

</DOC>
<DOC>
<DOCNO> 70034 </DOCNO>
Twist-4 quark-quark correlations in the pion from the instanton vacuum


  The result for the matrix element A(I=2) = -0.14 F_pi^2 appears to be an
artifact of an improper ultraviolet regularization. Paper withdrawn pending
resolution of this problem.

</DOC>
<DOC>
<DOCNO> 85567 </DOCNO>
Possible evidence for a variable fine structure constant from QSO


  An experimental search for variation in the fundamental coupling constants is
strongly motivated by modern high-energy physics theories. Comparison of quasar
absorption line spectra with laboratory spectra provides a sensitive probe for
variability of the fine structure constant, alpha, over cosmological
time-scales. We have previously developed and applied a new method providing an
order of magnitude gain in precision over previous optical astrophysical
constraints. Here we extend that work by including new quasar spectra of damped
Lyman-alpha absorption systems. We also re-analyse our previous lower redshift
data and confirm our initial results. The constraints on alpha come from
simultaneous fitting of absorption lines of subsets of the following species:
Mg I, Mg II, Al II, Al III, Si II, Cr II, Fe II, Ni II and Zn II. We present a
detailed description of our methods and results based on an analysis of 49
quasar absorption systems (towards 28 QSOs) covering the redshift range 0.5 < z
< 3.5. There is statistical evidence for a smaller alpha at earlier epochs:
da/a = (-0.72 +/- 0.18) * 10^{-5}. The new and original samples are independent
but separately yield consistent and significant non-zero values of da/a. We
summarise the results of a thorough investigation of systematic effects
published in a companion paper. The value we quote above is the raw value, not
corrected for any of these systematic effects. The only significant systematic
effects so far identified, if removed from our data, would lead to a more
significant deviation of da/a from zero.

</DOC>
<DOC>
<DOCNO> 118975 </DOCNO>
Circumbinary disks around T Tauri stars: HST/NICMOS near-infrared images


  We have obtained new near-infrared images of both GG Tau and UY Aur
circumbinary disks with the polarimetric modes of NICMOS aboard the Hubble
Space Telescope. The 1 micron intensity map of GG Tau reveals a more complete
elliptical shape than in previous ground-based images. Its eastern and western
sides are definitely asymmetric. Our image strongly supports the ring geometry
proposed by Guilloteau, Dutrey & Simon (1999) on the basis of their millimetre
interferometry images: a geometrically thick and sharply edged ring surrounding
an empty gap around the binary. Around UY Aur, we identify structures that are
in excellent agreement with the optical images of M\'enard et al. (1999), which
confirms that the inclination of the system to the line-of-sight is about 60
degrees. We also find tentative new structures closer to the stars.

</DOC>
<DOC>
<DOCNO> 150791 </DOCNO>
Comments on Central Charge of Topological Sigma Model with Calabi-Yau


  We study a central charge Z of a one parameter family of Calabi-Yau d-fold
embedded in CP^{d+1}. For a d-fold case, we construct the Z concretely and
analyze charge vectors of D-branes and intersection forms of associated cycles.
We find the charges are described as some kinds of Mukai vectors. They are
represented as products of Chern characters of coherent sheaves restricted on
the Calabi-Yau hypersurfaces and square roots of A-roof genera of the d-folds.
By combining results of the topological sigma model and the data of the CFT
calculations in the Gepner model, we find that the Z is determined and is
specified by a set of integers. It labels boundary states in special classes
where associated states are represented as tensor products of boundary states
for constituent minimal models. The Z has a moduli parameter t that describes a
deformation of a moduli space in the open string channel with B-type boundary
conditions. Also monodromy matrices and homology cycles are investigated.

</DOC>
<DOC>
<DOCNO> 13403 </DOCNO>
Charged Brownian Particle in a Magnetic Field


  We derive explicit forms of Markovian transition probability densities for
the velocity space and phase-space Brownian motion of a charged particle in a
constant magnetic field.

</DOC>
<DOC>
<DOCNO> 117198 </DOCNO>
Continuous-wave Doppler-cooling of hydrogen atoms with two-photon


  We propose and analyze the possibility of performing two-photon
continuous-wave Doppler-cooling of hydrogen atoms using the 1S-2S transition.
"Quenching" of the 2S level (by coupling with the 2P state) is used to increase
the cycling frequency, and to control the equilibrium temperature. Theoretical
and numerical studies of the heating effect due to Doppler-free two-photon
transitions evidence an increase of the temperature by a factor of two. The
equilibrium temperature decreases with the effective (quenching dependent)
width of the excited state and can thus be adjusted up to values close to the
recoil temperature.

</DOC>
<DOC>
<DOCNO> 13526 </DOCNO>
Bose-Einstein condensation in complex networks


  The evolution of many complex systems, including the world wide web, business
and citation networks is encoded in the dynamic web describing the interactions
between the system's constituents. Despite their irreversible and
non-equilibrium nature these networks follow Bose statistics and can undergo
Bose-Einstein condensation. Addressing the dynamical properties of these
non-equilibrium systems within the framework of equilibrium quantum gases
predicts that the 'first-mover-advantage', 'fit-get-rich' and
'winner-takes-all' phenomena observed in competitive systems are
thermodynamically distinct phases of the underlying evolving networks.

</DOC>
<DOC>
<DOCNO> 14079 </DOCNO>
Broken symmetry, hyper-fermions, and universal conductance in transport


  We have found solution to a model of tunneling between a multi-channel Fermi
liquid reservoir and an edge of the principal fractional quantum Hall liquid
(FQHL) in the strong coupling limit. The solution explains how the absence of
the time-reversal symmetry at high energies due to chiral edge propagation
makes the universal two-terminal conductance of the FQHL fractionally quantized
and different from that of a 1D Tomonaga-Luttinger liquid wire, where a similar
model but preserving the time-reversal symmetry predicts unsuppressed
free-electron conductance.

</DOC>
<DOC>
<DOCNO> 101018 </DOCNO>
The size of triangulations supporting a given link


  Let T be a triangulation of S^3 containing a link L in its 1-skeleton. We
give an explicit lower bound for the number of tetrahedra of T in terms of the
bridge number of L. Our proof is based on the theory of almost normal surfaces.

</DOC>
<DOC>
<DOCNO> 8721 </DOCNO>
Elastic Scattering as a Cause of Quantum Dephasing: The Conductance of


  A method is proposed for studying wave and particle transport in disordered
waveguide systems of dimension higher than unity by means of exact
one-dimensionalization of the dynamic equations in the mode representation. As
a particular case, the T=0 conductance of a two-dimensional quantum wire is
calculated, which exhibits ohmic behaviour, with length-dependent conductivity,
at any conductor length exceeding the electron quasi-classical mean free path.
The unconventional diffusive regime of charge transport is found in the range
of conductor lengths where the electrons are commonly considered as localized.
In quantum wires with more than one conducting channel, each being identified
with the extended waveguide mode, the inter-mode scattering is proven to serve
as a phase-breaking mechanism that prevents interference localization without
real inelasticity of interaction.

</DOC>
<DOC>
<DOCNO> 101203 </DOCNO>
O_e(G) is a free module over O(G)


  We show that the quantised function algebra O_e(G) of a simply-connected
semisimple algebraic group G at a root of unity is a free module over the
subring isomorphic to O(G).

</DOC>
<DOC>
<DOCNO> 67727 </DOCNO>
Aspects of Quantum Chromodynamics


  These lectures provide an overview of Quantum Chromodynamics (QCD), the SU(3)
gauge theory of the strong interactions. The running of the strong coupling and
the associated property of Asymptotic Freedom are analyzed. Some selected
experimental tests and the present knowledge of $\alpha_s$ and the quark masses
are briefly summarized. A short description of the QCD flavour symmetries and
the dynamical breaking of chiral symmetry is also given.

</DOC>
<DOC>
<DOCNO> 120526 </DOCNO>
On the "failure" of the standard model for Soft X-ray Transients in


  It is currently believed that the ``standard'' accretion disk theory
under-predicts the observed X-ray luminosity from Soft X-ray Transients (SXT)
in quiescence by as much as 4 to 6 orders of magnitude. This failure of the
standard model is considered to be an important argument for the existence of
the alternative mode of accretion -- Advection Dominated Accretion Flows (ADAF)
in astrophysics, since these flows allow a much higher level of X-ray emission
in quiescence, in agreement with the observations. Here we point out that, in
stark contrast to steady-state standard disks, such disks in quiescence (being
non-steady) produce most of the X-ray emission very far from the last stable
orbit. Taking this into account, these disks can accommodate the observed X-ray
luminosities of SXTs rather naturally. Our theory predicts that Fe K-alpha
lines from standard accretion disks in quiescence should be narrow even though
the cold disk goes all the way down to the last stable orbit.

</DOC>
<DOC>
<DOCNO> 40155 </DOCNO>
Event Shapes and Power Correction Results from HERA


  Inclusive event shape variables have been measured in the Breit Frame for
neutral current deep-inelastic positron-proton scattering using the H1 and ZEUS
detectors at HERA. The variables thrust, jet broadening, C-parameter, jet mass
and two kinds of differential two-jet rate have been studied in the kinematic
range 7 < Q < 100 GeV. The Q dependence of the shape variables have been
compared with QCD applying power corrections proportional to 1/Q^p to account
for hadronisation effects. The concept of power corrections is tested by
fitting the strong coupling constant alpha_s and a non-perturbative parameter
alpha(p-1)_bar.

</DOC>
<DOC>
<DOCNO> 122429 </DOCNO>
Emission line oscillations in the dwarf nova V2051 Ophiuchi


  We have detected coherent oscillations, at multiple frequencies, in the line
and continuum emission of the eclipsing dwarf nova V2051 Ophiuchi using the 10m
Keck II telescope. Our own novel data acquisition system allowed us to obtain
very fast spectroscopy using a continuous readout of the CCD on the LRIS
spectrograph. This is the first time that dwarf nova oscillations are detected
and resolved in the emission lines. The accretion disc is highly asymmetric
with a stronger contribution from the blue-shifted side of the disc during our
observations. The disc extends from close to the white dwarf out to the outer
regions of the primary Roche lobe.
  Continuum oscillations at 56.12s and its first harmonic at 28.06 s are most
likely to originate on the surface of a spinning white dwarf with the
fundamental period corresponding to the spin period. Balmer and Helium emission
lines oscillate with a period of 29.77s at a mean amplitude of 1.9%. The line
kinematics as well as the eclipse constraints indicate an origin in the
accretion disc at a radius of 12 R_wd. The amplitude of the emission line
oscillation modulates (0-4%) at a period of 488s, corresponding to the Kepler
period at R=12 R_wd. This modulation is due to the beating between the white
dwarf spin and the orbital motion in the disc.
  The observed emission line oscillations cannot be explained by a truncated
disc as in the intermediate polars. The observations suggest a non-axisymmetric
bulge in the disc, orbiting at 12R_wd, is required. The close correspondence
between the location of the oscillations and the circularisation radius of the
system suggests that stream overflow effects may be of relevance

</DOC>
<DOC>
<DOCNO> 12872 </DOCNO>
High-Dimensional Diffusive Growth


  We consider a model of aggregation, both diffusion-limited and ballistic,
based on the Cayley tree. Growth is from the leaves of the tree towards the
root, leading to non-trivial screening and branch competition effects. The
model exhibits a phase transition between ballistic and diffusion-controlled
growth, with non-trivial corrections to cluster size at the critical point.
Even in the ballistic regime, cluster scaling is controlled by extremal
statistics due to the branching structure of the Cayley tree; it is the
extremal nature of the fluctuations that enables us to solve the model.

</DOC>
<DOC>
<DOCNO> 150708 </DOCNO>
Hamilton-Jacobi equations and Brane associated Lagrangians


  This article seeks to relate a recent proposal for the association of a
covariant Field Theory with a string or brane Lagrangian to the Hamilton-Jacobi
formalism for strings and branes. It turns out that since in this special case,
the Hamiltonian depends only upon the momenta of the Jacobi fields and not the
fields themselves, it is the same as a Lagrangian, subject to a constancy
constraint. We find that the associated Lagrangians for strings or branes have
a covariant description in terms of the square root of the same Lagrangian. If
the Hamilton-Jacobi function is zero, rather than a constant, then it is in in
one dimension lower, reminiscent of the `holographic' idea. In the second part
of the paper, we discuss properties of these Lagrangians, which lead to what we
have called `Universal Field Equations', characteristic of covariant equations
of motion.

</DOC>
<DOC>
<DOCNO> 120249 </DOCNO>
Cosmological Density Perturbations in two fluid models on spin dominated


  A spinning fluid embedded in a space section flat Friedmann model is used to
compute the cosmological density perturbation of the model.The spinning fluid
obeys the Einstein-Cartan field equations while the Friedmann embedded model is
assumed to obey the general the Friedmann equation in General Relativity.It is
shown that at the early epochs of the Universe the spin-torsion contribution to
the density perturbation on the matter phase dominates over the radiation
perturbation.On the other hand at the present epochs of the Universe the
spin-torsion contribution is more efficient in the matter
perturbation.Stability of the Friedmann solution in Einstein-Cartan cosmology
is also discussed.

</DOC>
<DOC>
<DOCNO> 117959 </DOCNO>
Innermost stable circular orbits around strange stars and kHz QPOs in


  Exact calculations of innermost stable circular orbit (ISCO) around rotating
strange stars are performed within the framework of general relativity.
Equations of state (EOS) of strange quark matter based on the MIT Bag Model
with massive strange quarks and lowest order QCD interactions, are used. The
presence of a solid crust of normal matter on rotating, mass accreting strange
stars in LMXBs is taken into account. It is found that, contrary to neutron
stars, above some minimum mass a gap always separates the ISCO and stellar
surface, independently of the strange star rotation rate. For a given baryon
mass of strange star, we calculate the ISCO frequency as function of stellar
rotation frequency, from static to Keplerian configuration. For masses close to
the maximum mass of static configurations the ISCO frequencies for static and
Keplerian configurations are similar. However, for masses significantly lower
than the maximum mass of static configurations, the minimum value of the ISCO
frequency is reached in the Keplerian limit. Presence of a solid crust
increases the ISCO frequency for the Keplerian configuration by about ten
percent compared to that for a bare strange star of the same mass.

</DOC>
<DOC>
<DOCNO> 10765 </DOCNO>
Spin Tunneling in Fe$_8$ Molecular Nanomagnets [Comment on Europhys.


  Spin Tunneling in Fe8 powder : a comment on Europhys. Lett. 47, 722, 1999, by
Del Berco et al.

</DOC>
<DOC>
<DOCNO> 100643 </DOCNO>
Poisson cohomology in dimension two


  It is known that the computation of the Poisson cohomology is closely related
to the classification of singularities of Poisson structures. In this paper, we
will first look for the normal forms of germs at (0,0) of Poisson structures on
the real (or complex) plane and recall a result given by Arnold. Then, we will
compute locally the Poisson cohomology of a particular type of Poisson
structure.

</DOC>
<DOC>
<DOCNO> 100149 </DOCNO>
Recurrence relation for relativistic atomic matrix elements


  Recurrence formulae for arbitrary hydrogenic radial matrix elements are
obtained in the Dirac form of relativistic quantum mechanics. Our approach is
inspired on the relativistic extension of the second hypervirial method that
has been succesfully employed to deduce an analogous relationship in non
relativistic quantum mechanics. We obtain first the relativistic extension of
the second hypervirial and then the relativistic recurrence relation.
Furthermore, we use such relation to deduce relativistic versions of the
Pasternack-Sternheimer rule and of the virial theorem.

</DOC>
<DOC>
<DOCNO> 13873 </DOCNO>
The Structure of Langevin's Memory Kernel From Lagrangian Dynamics


  We obtain the memory kernel of the generalized Langevin equation, describing
a particle interacting with longitudinal phonons in a liquid. The kernel is
obtained analytically at T=0 Kelvin and numerically at T>0 Kelvin. We find that
it shows some non-trivial structural features like negative correlations for
some range of time separations. The system is shown to have three
characteristic time scales, that control the shape of the kernel, and the
transition between quadratic and linear behavior of the mean squared distance
(MSD). Although the derivation of the structure in the memory kernel is
obtained within a specific dynamical model, the phenomenon is shown to be quite
generic.

</DOC>
<DOC>
<DOCNO> 151004 </DOCNO>
General matter coupled N=2, D=5 gauged supergravity


  We give the full lagrangean and supersymmetry transformation rules for D=5,
N=2 supergravity interacting with an arbitrary number of vector, tensor and
hyper-multiplets, with gauging of the R-symmetry group SU(2)_R as well as a
subgroup K of the isometries of the scalar manifold. Among the many possible
applications, this theory provides the setting where a supersymmetric
brane-world scenario could occur. We comment on the presence of AdS vacua and
BPS solutions that would be relevant towards a supersymmetric smooth
realization of the Randall-Sundrum "alternative to compactification". We also
add some remarks on the connection between this most general 5D fully coupled
supergravity model and type IIB theory on the T^{11} manifold.

</DOC>
<DOC>
<DOCNO> 39832 </DOCNO>
Limits on Gravitino Production and New Processes with Large Missing


  Events collected by the Collider Detector at Fermilab (CDF) with an energetic
jet plus large missing transverse energy can be used to search for physics
beyond the Standard Model. We see no deviations from the expected background
and set upper limits on the production of new processes. We consider in
addition the production of light gravitinos within the framework of the Gauge
Mediated Supersymmetry Breaking models and set a limit at 95% confidence level
on the breaking scale sqrt(F) >= 217 GeV, which excludes gravitino masses
smaller than 1.1x10^-5 eV/c^2.

</DOC>
<DOC>
<DOCNO> 80810 </DOCNO>
The Infrared behaviour of the gluon propagator in SU(2) and SU(3)


  We present lattice results for the gluon propagator for SU(2) and SU(3) in
the Laplacian gauge which avoids lattice Gribov copies. In SU(3) we compare
with the most recent lattice calculation in Landau gauge and with various
approximate solutions of the Dyson Schwinger equations (DSE).

</DOC>
<DOC>
<DOCNO> 69970 </DOCNO>
Ultraviolet dependence of Kaluza-Klein effects on electroweak


  In extensions of the standard model (SM) with d extra dimensions at the TeV
scale the virtual exchange of Kaluza-Klein (KK) excitations of the gauge bosons
gives contributions that change the SM relations between electroweak
observables. These corrections are finite only for d=1; for d\ge 2 the infinite
tower of KK modes gives a divergent contribution that has to be regularized
introducing a cutoff (the string scale). However, the ultraviolet dependence of
the KK effects is completely different if the running of the couplings with the
scale is taken into account. We find that for larger d the number of
excitations at each KK level increases, but their larger number is compensated
by the smaller value of the gauge coupling at that scale. As a result, for any
number of extra dimensions the exchange of the complete KK tower always gives a
finite contribution. We show that (i) for d=1 the running of the gauge coupling
decreases an 14% the effect of the KK modes on electroweak observables; (ii) in
all cases more than 90% of the total effect comes from the excitations in the
seven lowest KK levels and is then independent of ultraviolet physics.

</DOC>
<DOC>
<DOCNO> 119780 </DOCNO>
Discovery of a 6.4 keV Emission Line in a Burst from SGR 1900+14


  We present evidence of a 6.4 keV emission line during a burst from the soft
gamma-ray repeater SGR 1900+14. The Rossi X-ray Timing Explorer (RXTE)
monitored this source extensively during its outburst in the summer of 1998. A
strong burst observed on August 29, 1998 revealed a number of unique
properties. The burst exhibits a precursor and is followed by a long (~ 1000 s)
tail modulated at the 5.16 s stellar rotation period. The precursor has a
duration of 0.85 s and shows both significant spectral evolution as well as an
emission feature centered near 6.4 keV during the first 0.3 s of the event,
when the X-ray spectrum was hardest. The continuum during the burst is well fit
with an optically thin thermal bremsstrahlung (OTTB) spectrum with the
temperature ranging from about 40 to 10 keV. The line is strong, with an
equivalent width of 400 eV, and is consistent with Fe K-alpha fluorescence from
relatively cool material. If the rest-frame energy is indeed 6.4 keV, then the
lack of an observed redshift indicates that the source is at least 80 km above
the neutron star surface. We discuss the implications of the line detection in
the context of models for SGRs.

</DOC>
<DOC>
<DOCNO> 169745 </DOCNO>
Resonance Fluorescence Spectrum of a Trapped Ion Undergoing Quantum


  We experimentally investigate the resonance fluorescence spectrum of single
171Yb and 172Yb ions which are laser cooled to the Lamb-Dicke regime in a
radiofrequency trap. While the fluorescence scattering of 172Yb is continuous,
the 171Yb fluorescence is interrupted by quantum jumps because a nonvanishing
rate of spontaneous transitions leads to electron shelving in the metastable
hyperfine sublevel 2D3/2(F=2). The average duration of the resulting dark
periods can be varied by changing the intensity of a repumping laser field.
Optical heterodyne detection is employed to analyze the fluorescence spectrum
near the Rayleigh elastic scattering peak. It is found that the stochastic
modulation of the fluorescence emission by quantum jumps gives rise to a
Lorentzian component in the fluorescence spectrum, and that the linewidth of
this component varies according to the average duration of the dark
fluorescence periods. The experimental observations are in quantitative
agreement with theoretical predictions.

</DOC>
<DOC>
<DOCNO> 102857 </DOCNO>
Matrix balls, radial analysis of Berezin kernels, and hypergeometric


  Consider the pseidounitary group $G=U(p,q)$ and its compact subgroup
$K=U(p)$. We construct an explicit unitary intertwining operator from the
tensor product of a holomorphic representation and a antiholomorphic
representation of $G$ to the space $L^2(G/K)$. This implies the existense of a
canonical action of the group $G\times G$ in $L^2(G/K)$. We also give a survey
of analysis of Berezin kernels and their relations with special functions.

</DOC>
<DOC>
<DOCNO> 9392 </DOCNO>
Cyclically coupled spreading and pair annihilation


  Recently it has been shown that the transition of the 1+1-dimensional
annihilation-fission process 2X->3X, 2X->0 exhibits an unusual type of
nonequilibrium critical behavior. The phenomenological properties of critical
clusters are characterized by two different dynamic modes for spreading and
diffusion. In order to describe the interplay of these modes, we introduce an
effective model which involves two species of particles A and B. The
A-particles perform an ordinary directed percolation process while the B
particles diffuse and annihilate. Both subsystems are cyclically coupled by
particle transmutation A <-> B. The resulting critical behavior is in many
respects similar to the one observed in the annihilation-fission process.

</DOC>
<DOC>
<DOCNO> 101979 </DOCNO>
Topology of the iso-spectral real manifolds associated with the


  This paper concerns the topology of isospectral real manifolds of certain
Jacobi elements associated with real split semisimple Lie algebras. The
manifolds are related to the compactified level sets of the generalized
(nonperiodic) Toda lattice equations defined on the semisimple Lie algebras. We
then give a cellular decomposition and the associated chain complex of the
manifold by introducing colored Dynkin diagrams which parametrize the cells in
the decomposition. We also discuss the Morse chain complex of the manifold.

</DOC>
<DOC>
<DOCNO> 169813 </DOCNO>
Non-orthogonal preferred projectors for modal interpretations of quantum


  Modal interpretations constitute a particular approach to associating
dynamical variables with physical systems in quantum mechanics. Given the
`quantum logical' constraints that are typically adopted by such
interpretations, only certain sets of variables can be taken to be
simultaneously definite-valued, and only certain sets of values can be ascribed
to these variables at a given time. Moreover, each allowable set of variables
and values can be uniquely specified by a single `preferred' projector in the
Hilbert space associated with the system. In general, the preferred projector
can be one of several possibilities at a given time. In previous modal
interpretations, the different possible preferred projectors have formed an
orthogonal set. This paper investigates the consequences of adopting a
non-orthogonal set. We present three contributions on this issue: (1) we
provide an argument for such non-orthogonality, based on the assumption that
perfectly predictable measurements reveal pre-existing values of variables, an
assumption which has traditionally constituted a strong motivation for the
modal approach; (2) we generalize the existing framework for modal
interpretations to accommodate non-orthogonal preferred projectors; (3) we
present a novel type of modal interpretation wherein the set of preferred
projectors is fixed by a principle of entropy minimization, and we discuss some
of the successes and shortcomings of this proposal.

</DOC>
<DOC>
<DOCNO> 8517 </DOCNO>
Phase Diagram Of A Hard-sphere System In A Quenched Random Potential: A


  We report numerical results for the phase diagram in the density-disorder
plane of a hard sphere system in the presence of quenched, random, pinning
disorder. Local minima of a discretized version of the Ramakrishnan-Yussouff
free energy functional are located numerically and their relative stability is
studied as a function of the density and the strength of disorder. Regions in
the phase diagram corresponding to liquid, glassy and nearly crystalline states
are mapped out, and the nature of the transitions is determined. The liquid to
glass transition changes from first to second order as the strength of the
disorder is increased. For weak disorder, the system undergoes a first order
crystallization transition as the density is increased. Beyond a critical value
of the disorder strength, this transition is replaced by a continuous glass
transition. Our numerical results are compared with those of analytical work on
the same system. Implications of our results for the field-temperature phase
diagram of type-II superconductors are discussed.

</DOC>
<DOC>
<DOCNO> 121717 </DOCNO>
N-band Imaging of Seyfert Nuclei and the MIR-X-ray correlation


  We present new mid-infrared (N-band) images of a sample of eight nearby
Seyfert galaxies. In all of our targets, we detect a central unresolved source,
which in some cases has been identified for the first time. In particular, we
have detected the mid-infrared emission from the active nucleus of NGC 4945,
which previously remained undetected at any wavelength but hard X-rays. We also
detect circumnuclear extended emission in the Circinus galaxy along its major
axis, and find marginal evidence for extended circumnuclear emission in NGC
3281.
  The high spatial resolution (1.7") of our data allows us to separate the flux
of the nuclear point sources from the extended circumnuclear starburst (if
present). We complement our sample with literature data for a number of
non-active starburst galaxies, and relate the nuclear N-band flux to published
hard (2-10 kev) X-ray fluxes. We find tight and well-separated correlations
between nuclear N-band flux and X-ray flux for both Seyfert and starburst
nuclei which span over 3 orders of magnitude in luminosity. We demonstrate that
these correlations can be used as a powerful classification tool for galactic
nuclei.
  For example, we find strong evidence against NGC 1808 currently harbouring an
active Seyfert nucleus based on its position in the mid-infrared-X-ray diagram.
On the other hand, we confirm that NGC 4945 is in fact a Seyfert 2 galaxy.

</DOC>
<DOC>
<DOCNO> 116817 </DOCNO>
Multipactoring Code for 3D Accelerating Structures


  The simulation code has been developed to investigate possible electron
multi- pacting in the 3D RF cavities using preliminary calculated field
components. The code provides different options of numerical study of the
electron multi- pacting including search of the resonant trajectories and
simulation of an electron multiplication.

</DOC>
<DOC>
<DOCNO> 7984 </DOCNO>
Influence of high-energy electron irradiation on the transport


  The effect of crystal lattice disorder on the conductivity and colossal
magnetoresistance in La_{1-x}Ca_{x}MnO_{3} (x \approx 0.33) films has been
examined. The lattice defects are introduced by irradiating the film with
high-energy (\simeq 6 MeV) electrons with a maximal fluence of about 2\times
10^{17} cm^{-2}. This comparatively low dose of irradiation produces rather
small radiation damage in the films. The number of displacements per atom (dpa)
in the irradiated sample is about 10^{-5}. Nethertheless, this results in an
appreciable increase in the film resistivity. The percentage of resistivity
increase in the ferromagnetic metallic state (below the Curie tempetature
T_{c}) was much greater than that observed in the insulating state (above
T_{c}). At the same time irradiation has much less effect on T_{c} or on the
magnitude of the colossal magnetoresistance. A possible explanation of such
behavior is proposed.

</DOC>
<DOC>
<DOCNO> 119967 </DOCNO>
A Plasma Prism Model for an Anomalous Dispersion Event in the Crab


  In 1997 October daily monitoring observations of the Crab pulsar at 327 MHz
and 610 MHz with an 85ft telescope in Green Bank, WV showed a jump in the
dispersion measure by 0.1 cm$^{-3}$ pc. Pulses were seen simultaneously at both
old and new dispersions over the course of several days. During the dispersion
jump the pulsed flux diminished by an order of magnitude. In the months before
this event the average pulse profiles contained faint ``ghost'' pulse
components offset in phase from the regular main pulse and interpulse
components by a nearly frequency independent time delay that quadratically
diminished to zero over a month. After the dispersion event there was an order
of magnitude increase in the level of scattering, as measured by pulse
broadening at 327 MHz. There was also a curious shift in the rotational phase,
a slowing down, at both frequencies at the time of the dispersion jump which we
associate with intrinsic timing noise. All of the observed phenomena except
this slowing down can be explained by the variable perturbing optics of a
triangular plasma prism that is located in the filamentary interface between
the synchrotron nebula and the supernova ejecta and which crosses the line of
sight over a period of months. The required density, scale length and velocity
are reasonable given previous observations and analysis of these filaments. Our
study thus provides a probe of the plasma column on scales of 30 microarcsecond
to 3 milliarcsecond ($10^{12-14}$ cm) which complements scales accessible to
optical emission line studies with HST resolution ($10^{16-18}$ cm). In
combination both observations provide a detailed look at a sample of the
interface region that can be matched statistically to the results of numerical
simulations.

</DOC>
<DOC>
<DOCNO> 69685 </DOCNO>
K-meson neutrinoless double muon decay as a probe of neutrino masses and


  Recently an upper bound on the rate of the lepton number violating decay
$K^+\to \mu^+\mu^+\pi^-$ has been significantly reduced by the E865 experiment
at BNL and further improvement is expected in the near future. We study this
process as a possible source of information on neutrino masses and mixings. We
find that it is insensitive to the light(eV domain) and heavy(GeV domain)
neutrinos. However due to the effect of a resonant enhancement this decay is
very sensitive to neutrinos $\nu_j$ in the mass region $245{MeV}\leq
m_{\nu_j}\leq 389$ MeV. At present experimental sensitivity we deduce new
stringent limits on the neutrino mixing matrix element $U_{\mu j}$ for neutrino
masses in this region.

</DOC>
<DOC>
<DOCNO> 12041 </DOCNO>
Electronic properties of the degenerate Hubbard Model : A dynamical mean


  We have investigated electronic properties of the degenerate multi-orbital
Hubbard model, in the limit of large spatial dimension. A new local model,
including a doubly degenerate strongly correlated site has been introduced and
solved in the framework of the non-crossing approximation (NCA). Mott-Hubbard
transitions have been examined in details, including the calculation of Coulomb
repulsion critical values and electronic densities of states for any regime of
parameters.

</DOC>
<DOC>
<DOCNO> 152361 </DOCNO>
Transformation of the Dirac-Born-Infeld action under the Seiberg-Witten


  We explicitly evaluate the disk S-matrix elements of one closed string and an
arbitrary number of open string states in the presence of a large background
B-flux. From this calculation, we show that in the world-volume action of
D-branes in terms of non-commutative fields, the closed string fields must be
treated as functionals of the non-commutative gauge fields. We also find the
generalized multiplication rule *_N between N open string fields on the
world-volume of the D-brane. In particular, this result indicates that the
difference between the familiar * and the *_N product is just some total
derivative terms. We show that the *_N product and the dependence of the closed
string fields on the non-commutative gauge fields emerge also from transforming
the ordinary Dirac-Born-Infeld action(including the closed string fields) under
the Seiberg-Witten map. We then conjecture a non-commutative DBI action for the
transformation of the commutative DBI action under the SW map.

</DOC>
<DOC>
<DOCNO> 101083 </DOCNO>
On a class of bounded quantum fields


  Local quantum fields in 1+1 dimensions can have bounded field operators. The
class of such fields which in addition obey Huygens' principle (time-like
commutativity) and conformal covariance, is completely determined.

</DOC>
<DOC>
<DOCNO> 102041 </DOCNO>
A new six dimensional irreducible symplectic variety


  By results of the author there exists a projective (holomorphic) symplectic
desingularization of the moduli space of rank-two torsion-free sheaves on a
genus-two Jacobian with $c_1=0$ and $c_2=2$. This desingularization has a
natural map to the self-product of the Jacobian. We show that the fiber over
$(0,0)$ is a 6-dimensional projective irreducible symplectic variety (and hence
a 12-dimensional compact Hyperkahler manifold) with second Betti number equal
to 8. Thus it is not deformation equivalent to any of the (few) known examples
of irreducible symplectic varieties, even up to birational equivalence.

</DOC>
<DOC>
<DOCNO> 101821 </DOCNO>
Closed nodal lines and interior hot spots of the second eigenfunction of


  We build a one-parameter family of S^{1}-invariant metrics on the unit disc
with fixed total area for which the second eigenvalue of the Laplace operator
in the case of both Neumann and Dirichlet boundary conditions is simple and has
an eigenfunction with a closed nodal line. In the case of Neumann boundary
conditions, we also prove that this eigenfunction attains its maximum at an
interior point, and thus provide a counterexample to the hot spots conjecture
on a simply connected surface. This is a consequence of the stronger result
that within this family of metrics any given (finite) number of S^{1}-invariant
eigenvalues can be made to be arbitrarily small, while the non-invariant
spectrum becomes arbitrarily large.

</DOC>
<DOC>
<DOCNO> 118378 </DOCNO>
Analysis of Balmer Profiles of early type stars


  The spectral energy distribution (SED) of recent star formation regions is
dominated by the more massive and early stars (O and B types). These stars show
large and very significant absorption features, the most prominent being the
recombination lines of H, HeI and HeII. In particular, the shape of their
profiles are very dependent on the luminosity of the star. We have explored the
potential use of high resolution profiles to discriminate between different
luminosity classes and spectral types, by using profiles of the He and Balmer
lines. We have calculated growth curves for each of the lines and their
dependence on gravity and effective temperature. We show some of these
theoretical growth curves and our preliminary conclusions are analyzed and
discussed.

</DOC>
<DOC>
<DOCNO> 12839 </DOCNO>
Computer Science in Physics


  This talk describes how techniques developed by Computer Scientists have
helped our understanding of certain problems in statistical physics which
involve randomness and ``frustration''. Examples will be given from two
problems that have been widely studied: the ``spin glass'' and the ``random
field model''.

</DOC>
<DOC>
<DOCNO> 67900 </DOCNO>
Vacuum Polarisation Tensors in Constant Electromagnetic Fields: Part I


  The string-inspired technique is used for the calculation of vacuum
polarisation tensors in constant electromagnetic fields. In the first part of
this series, we give a detailed exposition of the method for the case of the
QED one-loop N-photon amplitude in a general constant electromagnetic
background field. The two-point cases are calculated explicitly, leading to
compact representations for the constant field vacuum polarisation tensors for
both scalar and spinor QED.

</DOC>
<DOC>
<DOCNO> 99884 </DOCNO>
Every homotopy theory of simplicial algebras admits a proper model


  We show that any closed model category of simplicial algebras over an
algebraic theory is Quillen equivalent to a proper closed model category. By
``simplicial algebra'' we mean any category of algebras over a simplicial
algebraic theory, which is allowed to be multi-sorted. The results have
applications to the construction of localization model category structures.

</DOC>
<DOC>
<DOCNO> 70590 </DOCNO>
Probing Light Sbottoms with B Decays


  We discuss recently reported experimental hints for a bottom squark with mass
around 3.5 GeV decaying as sbottom -> charm + lepton + anti-sneutrino. We
correlate the sbottom lifetime with the decay rates for bottom -> sbottom +
neutrino + anti-sneutrino and bottom -> sbottom + anti-neutrino + sneutrino in
the framework of a minimal supersymmetric model extended by right-handed
(s)neutrinos. Confronting our results with the well-measured semileptonic
branching ratio of B mesons we conclude that the light sbottom interpretation
of the experimental anomalies is ruled out, unless m_bottom < m_sbottom +
m_sneutrino.

</DOC>
<DOC>
<DOCNO> 8768 </DOCNO>
Momentum distribution of an interacting Bose-condensed gas at finite


  We use a semiclassical two-fluid model to study the momentum distribution of
a Bose-condensed gas with repulsive interactions inside a harmonic trap at
finite temperature, with specific focus on atomic hydrogen. We give particular
attention to the average kinetic energy, which is almost entirely associated
with the thermal cloud. A non-linear dependence of the kinetic energy on
temperature is displayed, affording a precise way to assess the temperature of
the gas. We also show that the kinetic energy increases with the strength of
the interactions, reflecting an enhanced rate of depletion of the condensate
with increasing temperature.

</DOC>
<DOC>
<DOCNO> 69556 </DOCNO>
Space-time description of the hadron interaction at high energies


  This is a classical paper by Vladimir Gribov (1930-97) which has influenced
the understanding of high energy hadron collisions and deep inelastic
scattering for several decades, and is still important today. Gribov's main
assumption - that partons have limited transverse momenta - was later proved to
be satisfied in QCD, modulo logarithmic corrections. However, QCD was just
coming into existence at the time of the lecture, and Gribov used the
super-renormalizable \phi^3 theory to illustrate his points.

</DOC>
<DOC>
<DOCNO> 71613 </DOCNO>
Measuring the BFKL Pomeron in Neutrino Telescopes


  We present a new method for obtaining information on the small x behavior of
the structure function F2 outside the kinematic range of present acelerators
from the mean inelasticity parameter in UHE neutrino-nucleon DIS interactions
which could be measured in neutrino telescopes.

</DOC>
<DOC>
<DOCNO> 8314 </DOCNO>
Sonic analog of gravitational black holes in Bose-Einstein condensates


  It is shown that, in dilute-gas Bose-Einstein condensates, there exist both
dynamically stable and unstable configurations which, in the hydrodynamic
limit, exhibit a behavior resembling that of gravitational black holes. The
dynamical instabilities involve creation of quasiparticle pairs in positive and
negative energy states, as in the well-known suggested mechanism for black hole
evaporation. We propose a scheme to generate a stable sonic black hole in a
ring trap.

</DOC>
<DOC>
<DOCNO> 116263 </DOCNO>
Calculation of positron binding to silver and gold atoms


  Positron binding to silver and gold atoms was studied using a fully {\it ab
initio} relativistic method, which combines the configuration interaction
method with many-body perturbation theory. It was found that the silver atom
forms a bound state with a positron with binding energy 123 ($\pm$ 20%) meV,
while the gold atom cannot bind a positron. Our calculations reveal the
importance of the relativistic effects for positron binding to heavy atoms. The
role of these effects was studied by varying the value of the fine structure
constant $\alpha$. In the non-relativistic limit, $\alpha = 0$, both systems
$e^+$Ag and $e^+$Au are bound with binding energies of about 200 meV for
$e^+$Ag and 220 meV for $e^+$Au. Relativistic corrections for a negative ion
are essentially different from that for a positron interacting with an atom.
Therefore, the calculation of electron affinities cannot serve as a test of the
method used for positron binding in the non-relativistic case. However, it is
still a good test of the relativistic calculations. Our calculated electron
affinities for silver (1.327 eV) and gold (2.307 eV) atoms are in very good
agreement with corresponding experimental values (1.303 eV and 2.309 eV
respectively).

</DOC>
<DOC>
<DOCNO> 178751 </DOCNO>
Delta-Hole Interaction in Nuclei and the Gamow-Teller Strength in ^90Nb


  The recently obtained experimental result for the quenching of the GT sum
rule in the reaction ^90Zr(p,n)^90Nb is used to extract the value of the
Landau-Migdal parameter g_{N\Delta}', taking into account also the effect of
the finite range meson exchange interactions. The extracted value is compared
to the one obtained in the \pi+\rho exchange model by explicitly taking into
account the effects of antisymmetrization and short range correlations.
Although the \pi+\rho exchange model tends to give a somewhat stronger
quenching than observed experimentally, the results are consistent within the
experimental error bars if the quark model value for the parameter
f_\Delta/f_\pi is used.

</DOC>
<DOC>
<DOCNO> 169700 </DOCNO>
Beyond single-photon localization at the edge of a Photonic Band Gap


  We study spontaneous emission in an atomic ladder system, with both
transitions coupled near-resonantly to the edge of a photonic band gap
continuum. The problem is solved through a recently developed technique and
leads to the formation of a ``two-photon+atom'' bound state with fractional
population trapping in both upper states. In the long-time limit, the atom can
be found excited in a superposition of the upper states and a ``direct''
two-photon process coexists with the stepwise one. The sensitivity of the
effect to the particular form of the density of states is also explored.

</DOC>
<DOC>
<DOCNO> 40040 </DOCNO>
Neutron production by cosmic-ray muons at shallow depth


  The yield of neutrons produced by cosmic ray muons at a shallow depth of 32
meters of water equivalent has been measured. The Palo Verde neutrino detector,
containing 11.3 tons of Gd loaded liquid scintillator and 3.5 tons of acrylic
served as a target. The rate of one and two neutron captures was determined.
Modeling the neutron capture efficiency allowed us to deduce the total yield of
neutrons $ Y_{tot} = (3.60 \pm 0.09 \pm 0.31) \times 10^{-5}$ neutrons per muon
and g/cm$^2$. This yield is consistent with previous measurements at similar
depths.

</DOC>
<DOC>
<DOCNO> 150761 </DOCNO>
Algebraic characterization of constraints and generation of mass in


  The possibility of non-trivial representations of the gauge group on
wavefunctionals of a gauge invariant quantum field theory leads to a generation
of mass for intermediate vector and tensor bosons. The mass parameters "m" show
up as central charges in the algebra of constraints, which then become of
second-class nature. The gauge group coordinates acquire dynamics outside the
null-mass shell and provide the longitudinal field degrees of freedom that
massless bosons need to form massive bosons.

</DOC>
<DOC>
<DOCNO> 11529 </DOCNO>
Theory of Coexistence of Superconductivity and Ferroelectricity : A


  We propose and investigate a model for the coexistence of Superconductivity
(SC) and Ferroelectricity (FE) based on the dynamical symmetries $su(2)$ for
the pseudo-spin SC sector, $h(4)$ for the displaced oscillator FE sector, and
$su(2) \otimes h(4) $ for the composite system. We assume a minimal
symmetry-allowed coupling, and simplify the hamiltonian using a double mean
field approximation (DMFA). A variational coherent state (VCS) trial
wave-function is used for the ground state: the energy, and the relevant order
parameters for SC and FE are obtained. For positive sign of the SC-FE coupling
coefficient, a non-zero value of either order parameter can suppress the other
(FE polarization suppresses SC and vice versa). This gives some support to
"Matthias' Conjecture" [1964], that SC and FE tend to be mutually exclusive.
For such a Ferroelectric Superconductor we predict: a) the SC gap $\Delta $
(and $T_c $) will increase with increasing applied pressure when pressure
quenches FE as in many ferroelectrics, and b) the FE polarization will increase
with increaesing magnetic field up to $H_c $. The last result is equivalent to
the prediction of a new type of Magneto-Electric Effect in a coexistent SC-FE
material. Some discussion will be given of the relation of these results to the
cuprate superconductors.

</DOC>
<DOC>
<DOCNO> 69123 </DOCNO>
Neutrino Degeneracy and Decoupling: New Limits from Primordial


  We reanalyze the cosmological constraints on the existence of a net universal
lepton asymmetry and neutrino degeneracy. We show that neutrinos can begin to
decouple at higher temperatures than previous estimates due to several
corrections which diminish the neutrino reaction rate. These decoupled
neutrinos are therefore not heated as the particle degrees of freedom change.
The resultant ratio of the relic neutrino-to-photon temperatures after $e^\pm$
annihilation can then be significantly reduced by more than a factor of two
from that of the standard nondegenerate ratio. This changes the expansion rate
and subsequent primordial nucleosynthesis, photon decoupling, and structure
formation. In particular we analyze physically plausible lepton-asymmetric
models with large $\nu_\mu$ and $\nu_\tau$ degeneracies together with a
moderate $\nu_e$ degeneracy. We show that the nucleosynthesis by itself permits
very large neutrino degeneracies $0 \le \xinum$, $\xinut \le 40$, $0 \le \xinue
\le 1.4$ together with large baryon densities $0.1 \le \Omega_b \h502 \le 1$ as
long as some destruction of primordial lithium has occurred. We also show that
structure formation and the power spectrum of the cosmic microwave background
allows for the possibility of an $\Omega = 1$, $\Omega_\Lambda = 0.4$,
cosmological model for which there is both significant lepton asymmetry ($|
\xinum | = | \xinut | \approx 11$) and a relatively large baryon density
($\Omega_b \h502 \approx 0.2$). Our best-fit neutrino-degenerate,
high-baryon-content models are mainly distinguished by a suppression of the
second peak in the microwave background power spectrum. This is consistent with
the recent high resolution data from BOOMERANG and MAXIMA-1.

</DOC>
<DOC>
<DOCNO> 102422 </DOCNO>
Symmetry of links and classification of lens spaces


  We give a concise proof of a classification of lens spaces up to
orientation-preserving homeomorphisms. The chief ingredient in our proof is a
study of the Alexander polynomial of ` symmetric' links in $S^3$.

</DOC>
<DOC>
<DOCNO> 11247 </DOCNO>
Testing a hypothesis for the evolution of sex


  An asexual set of primitive bacteria is simulated with a bit-string Penna
model with a Fermi function for survival. A recent hypothesis by Jan, Stauffer
and Moseley on the evolution of sex from asexual cells as a strategy for trying
to escape the effects of deleterious mutations is checked. This strategy is
found to provide a successful scenario for the evolution of a stable
macroscopic sexual population.

</DOC>
<DOC>
<DOCNO> 84157 </DOCNO>
A testable description of space-time foam as a fundamental stochastic


  I develop a phenomenological approach to the description of the noise levels
that the space-time foam of quantum gravity could induce in modern gravity-wave
detectors. Various possibilities are considered, including white noise and
random-walk noise. In particular, I find that the sensitivity level expected
for the planned LIGO and VIRGO interferometers and for the next upgrade of the
NAUTILUS resonant-bar detector corresponds to a white-noise level which can be
naturally associated with the Planck length.

</DOC>
<DOC>
<DOCNO> 13527 </DOCNO>
Solving inverse problems by combination of maximum entropy and


  The montecarlo method, which is quite commonly used to solve maximum entropy
problems in statistical physics, can actually be used to solve inverse problems
in a much wider context. The probability distribution which maximizes entropy
can be calculated analytically by introducing Lagrange parameters. The problem
of fixing these lagrangean parameters is circumvented by introduction of a
microcanonical ensemble which describes a system together with its heath bath.
Some further simplifying assumptions make it feasible to do montecarlo sampling
of the probability distribution. The method is applied to the example of
determining the distribution of the density of the earth from three data.
Advantages of the method are guaranteed convergence and a clear
information-theoretic foundation.

</DOC>
<DOC>
<DOCNO> 150467 </DOCNO>
Bound states of neutral particles in external electric fields


  Neutral fermions of spin $\frac 12$ with magnetic moment can interact with
electromagnetic fields through nonminimal coupling. The Dirac--Pauli equation
for such a fermion coupled to a spherically symmetric or central electric field
can be reduced to two simultaneous ordinary differential equations by
separation of variables in spherical coordinates. For a wide variety of central
electric fields, bound-state solutions of critical energy values can be found
analytically. The degeneracy of these energy levels turns out to be numerably
infinite. This reveals the possibility of condensing infinitely many fermions
into a single energy level. For radially constant and radially linear electric
fields, the system of ordinary differential equations can be completely solved,
and all bound-state solutions are obtained in closed forms. The radially
constant field supports scattering solutions as well. For radially linear
fields, more energy levels (in addition to the critical one) are infinitely
degenerate. The simultaneous presence of central magnetic and electric fields
is discussed.

</DOC>
<DOC>
<DOCNO> 80607 </DOCNO>
On the topological structure of the QCD vacuum


  A review of results from lattice studies using improved and scale controlled
cooling methods is presented and their significance is discussed. The
improvement of the action ensures stable instanton solutions of physical sizes.
The scale controlled cooling can be generally used as a gauge invariant low
pass filter to extract the physics from noisy MC configurations; in particular
it preserves instanton-antiinstanton pairs selected according to their
interaction. We apply these methods to analyze various features of the
topological structure of the Yang-Mills vacuum in a scaling invariant way.

</DOC>
<DOC>
<DOCNO> 101172 </DOCNO>
Semisimple Triangular Hopf Algebras and Tannakian Categories


  One of the most fundamental problems in the theory of finite- dimensional
Hopf algebras is their classification over an algebraically closed field k of
characteristic 0. This problem is extremely difficult, hence people restrict it
to certain classes of Hopf algebras, e.g. to semisimple ones. Semisimple Hopf
algebras deserve to be considered as "quantum" analogue of finite groups, but
even so, the problem remains extremely hard (even in low dimensions) and very
little is known. A great boost to the theory of Hopf algebras was given by
Drinfeld who invented the fundamental class of (quasi)triangular Hopf algebras
(A,R). Thus, it is natural to first try to classify semisimple triangular Hopf
algebras (A,R) over k (i.e. R is unitary). The theory of such Hopf algebras is
now essentially closed by a sequence of works by P. Etingof and the author. The
key theorem in this theory states that A is obtained from a group algebra of a
unique (up to isomorphism) finite group by twisting its usual comultiplication.
The proof of this theorem relies on Deligne's theorem on Tannakian categories
in an essentail way. The purpose of this paper is to explain the proof in full
details. In particular, to discuss all the necessary background from category
theory (e.g. symmetric, rigid, and Tannakian categories), and the properties of
the category of representations of triangular (semisimple) Hopf algebras.

</DOC>
<DOC>
<DOCNO> 68905 </DOCNO>
Quark mixings and flavor changing interactions with singlet quarks


  Aspects of the quark mixings and flavor changing interactions are
investigated in electroweak models with singlet quarks. The effects on the
ordinary quark mixing are determined in terms of the quark masses and the
parameters describing the mixing between the ordinary quarks q and the singlet
quarks Q (q-Q mixing). Some salient features arise in the flavor changing
interactions through the q-Q mixing. The unitarity of the
Cabibbo-Kobayashi-Maskawa (CKM) matrix within the ordinary quark sector is
violated, and the flavor changing neutral currents (FCNC's) appear both in the
gauge and scalar couplings. The flavor changing interactions are calculated
appropriately in terms of the q-Q mixing parameters and the quark masses, which
really exhibit specific flavor structures. It is found that there are
reasonable ranges of the model parameters to reproduce the ordinary quark mass
hierarchy and the actual CKM structure even in the presence of q-Q mixing. Some
phenomenological effects of the singlet quarks are also discussed. In
particular, the scalar FCNC's may be more important in some cases, if the
singlet quarks as well as the extra scalar particles from the singlet Higgs
fields have masses $\sim$ 100 GeV -- 1 TeV.

</DOC>
<DOC>
<DOCNO> 101557 </DOCNO>
Logarithmic heat projective operators


  Let $f:\Cal C\to S$ be a flat family of curves over a smooth curve $S$ such
that $f$ is smooth over $S_0=S\ssm\{s_0\}$ and $f^{-1}(s_0)=\Cal C_0$ is
irreducible with one node. We have an associated family $\Cal M_{S_0}\to S_0$
of moduli spaces of semistable vector bundles and the relative theta line
bundle $\Theta_{S_0}$. We are interested in the problem: to find suitable
degeneration $\Cal M_S$ of moduli spaces and extension $\Theta_S$ of theta line
bundles such that the direct image of $\Theta_S$ is a vector bundle on $S$ with
a logarithmic projective connection. In this paper, we figured out the
conditions of existence of the connection and solved the problem for rank one.

</DOC>
<DOC>
<DOCNO> 118210 </DOCNO>
Jet directions in Seyfert galaxies


  We present the study of the relative angle between the accretion disk (or
radio jet) and the galaxy disk for a sample of Seyfert galaxies selected from a
mostly isotropic property, the 60$\mu$m flux. For each galaxy we have a pair of
points ($i$,$\delta$), which are the inclination of the galaxy relative to the
line of sight and the angle between the jet projected into the plane of the sky
and the host galaxy major axis, respectively. This data is combined with a
statistical technique to determine the distribution of $\beta$ angles {\it in 3
dimensions}, the angle between the jet and the host galaxy plane axis. The
analysis of the data, not differentiating between Seyfert 1's and 2's, showed
that the observed distribution of $i$ and $\delta$ values can be well
represented by a homogeneous $\beta-$distribution in the range
$0^{\circ}\leq\beta\leq90^{\circ}$. However, when we distinguished between
Seyfert 1's and 2's, the models could not represent Seyfert 1's adequately. It
was necessary to introduce viewing angle restrictions, that a galaxy can only
be recognized as a Seyfert 1 if the angle between the jet and the line of sight
($|\phi|$) is smaller than a given angle $\phi_c$ and that the galaxy
inclination $i$ is smaller than an angle $i_c$, in order to have statistically
acceptable models. This is a direct and independent confirmation of the
underlying concepts of the Unified Model. We discuss several ways to explain
the misalignment between the accretion disk axis and the host galaxy disk axis.

</DOC>
<DOC>
<DOCNO> 80577 </DOCNO>
Chiral condensate in the quenched Schwinger model


  A numerical investigation of the quenched Schwinger model on the lattice
using the overlap Dirac operator points to a divergent chiral condensate.

</DOC>
<DOC>
<DOCNO> 122884 </DOCNO>
Supernovae as stellar objects


  Type Ia supernovae (SN Ia) are generally believed to be the result of the
thermonuclear disruption of Chandrasekhar-mass carbon-oxygen white dwarfs,
mainly because such thermonuclear explosions can account for the right amount
of nickel, which is needed to explain the light curves and the late-time
spectra, and the abundances of intermediate-mass nuclei which dominate the
spectra near maximum light. Because of their enormous brightness and apparent
homogeneity SN Ia have become an important tool to measure cosmological
parameters.
 In this article the present understanding of the physics of thermonuclear
explosions is reviewed. In particular, we focus our attention on subsonic
("deflagration") fronts, i.e. we investigate fronts propagating by heat
diffusion and convection rather than by compression. Models based upon this
mode of nuclear burning have been applied very successfully to the SN Ia
problem, and are able to reproduce many of their observed features remarkably
well. However, the models also indicate that SN Ia may differ considerably from
each other, which is of importance if they are to be used as standard candles.

</DOC>
<DOC>
<DOCNO> 119600 </DOCNO>
The Identification of the Submillimeter Galaxy SMM J00266+1708


  We report the detection of 1.3mm continuum and near-infrared K-band
(2.2-micron) emission from the submillimeter galaxy SMM J00266+1708. Although
this galaxy is among the brightest sub-mm sources detected in the blank-sky
surveys (L~10^{13} L[sun]), SMM J00266+1708 had no reliable
optical/near-infrared counter-part. We used sensitive interferometric 1.3mm
observations with the Owens Valley Millimeter Array to accurately determine the
position of the sub-mm galaxy. Follow-up near-infrared imaging with the Keck I
telescope uncovered a new faint red galaxy at K=22.5 mag which is spatially
coincident with the 1.3mm emission. This is currently the faintest confirmed
counter-part of a sub-mm galaxy. Although the redshift of SMM J00266+1708 is
still unknown, its high sub-mm/radio spectral index suggests that the system is
at high redshift (z>2). Approximately 50% or more of the sub-mm galaxies are
faint/red galaxies similar to that of SMM J00266+1708. These ultraluminous
obscured galaxies account for a significant fraction of the total amount of
star-formation at high redshift despite being missed by optical/ultraviolet
surveys.

</DOC>
<DOC>
<DOCNO> 10054 </DOCNO>
Disorder from Disorder in a Strongly Frustrated Transverse Field Ising


  We study a one-dimensional chain of corner-sharing triangles with
antiferromagnetic Ising interactions along its bonds. Classically, this system
is highly frustrated with an extensive entropy at T = 0 and exponentially
decaying spin correlations. We show that the introduction of a quantum
dynmamics via a transverse magnetic field removes the entropy and opens a gap,
but leaves the ground state disordered at all values of the transverse field,
thereby providing an analog of the "disorder by disorder" scenario first
proposed by Anderson and Fazekas in their search for resonating valence bond
states. Our conclusion relies on exact diagonalization calculations as well as
on the analysis of a 14th order series expansion about the large transverse
field limit. This test suggests that the series method could be used to search
for other instances of quantum disordered states in frustrated transverse field
magnets in higher dimensions.

</DOC>
<DOC>
<DOCNO> 102433 </DOCNO>
Tautly foliated 3-manifolds with no R-covered foliations


  A foliation of a manifold M is called R-covered if its lift to the universal
cover of M has space of leaves R. We show that there are many graph manifolds
which admit taut foliations, but which do not admit any R-covered foliations.
On the other hand, we show that these manifolds all have finite covers
admitting R-covered foliations.

</DOC>
<DOC>
<DOCNO> 119553 </DOCNO>
Polarization in Sagittarius A*


  We summarize the current state of polarization observations of Sagittarius
A*, the compact radio source and supermassive black hole candidate in the
Galactic Center. These observations are providing new tools for understanding
accretion disks, jets and their environments. Linear polarization observations
have shown that Sgr A* is unpolarized at frequencies as high as 86 GHz.
However, recent single-dish observations indicate that Sgr A* may have strong
linear polarization at frequencies higher than 150 GHz. Circular polarization,
which was recently discovered in Sgr A*, is detectable to frequencies as high
as 43 GHz. It is strongly variable on a 10-day timescale, with the degree of
variability increasing with frequency. At low frequencies, fractional circular
polarization is stable over nearly 20 years. We discuss some of the possible
models for the origin of the circular polarization.

</DOC>
<DOC>
<DOCNO> 122686 </DOCNO>
Distance-Redshift in Inhomogeneous $Omega_0=1$


  Distance--redshift relations are given in terms of associated Legendre
functions for partially filled beam observations inspatially flat
Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmologies. These models are
dynamically pressure-free, flat FLRW on large scales but, due to mass
inhomogeneities, differ in their optical properties. The partially filled beam
area-redshift equation is a Lame$^{\prime}$ equation for arbitrary FLRW and is
shown to simplify to the associated Legendre equation for the spatially flat,
i.e. $\Omega_0=1$ case. We fit these new analytic Hubble curves to recent
supernovae (SNe) data in an attempt to determine both the mass parameter
$\Omega_m$ and the beam filling parameter $\nu$. We find that current data are
inadequate to limit $\nu$. However, we are able to estimate what limits are
possible when the number of observed SNe is increased by factor of 10 or 100,
sample sizes achievable in the near future with the proposed SuperNova
Acceleration Probe satellite.

</DOC>
<DOC>
<DOCNO> 70487 </DOCNO>
LHC Signature of the Minimal SUGRA Model with a Large Soft Scalar Mass


  Thanks to the focus point phenomenon, it is quite {\it natural} for the
minimal SUGRA model to have a large soft scalar mass m_0 > 1 TeV. A distinctive
feature of this model is an inverted hierarchy, where the lighter stop has a
significantly smaller mass than the other squarks and sleptons. Consequently,
the gluino is predicted to decay dominantly via stop exchange into a channel
containing 2b and 2W along with the LSP. We exploit this feature to construct a
robust signature for this model at the LHC in leptonic channels with 3-4 b-tags
and a large missing-E_T.

</DOC>
<DOC>
<DOCNO> 119591 </DOCNO>
Hydrodynamical Survey of First Overtone Cepheids


  A hydrodynamical survey of the pulsational properties of first overtone
Galactic Cepheids is presented. The goal of this study is to reproduce their
observed light- and radial velocity curves. The comparison between the models
and the observations is made in a quantitative manner on the level of the
Fourier coefficients. Purely radiative models fail to reproduce the observed
features, but convective models give good agreement.
  It is found that the sharp features in the Fourier coefficients are indeed
caused by the P1/P4 = 2 resonance, despite the very large damping of the 4th
overtone. For the adopted mass-luminosity relation the resonance center lies
near a period of 4.2d +/- 0.2 as indicated by the observed radial velocity
data, rather than near 3.2d as the light-curves suggest.

</DOC>
<DOC>
<DOCNO> 40543 </DOCNO>
Vertex Reconstructing Neural Network at the ZEUS Central Tracking


  An unconventional solution for finding the location of event creation is
presented. It is based on two feed-forward neural networks with fixed
architecture, whose parameters are chosen so as to reach a high accuracy. The
interaction point location is a parameter that can be used to select events of
interest from the very high rate of events created at the current experiments
in High Energy Physics. The system suggested here is tested on simulated data
sets of the ZEUS Central Tracking Detector, and is shown to perform better than
conventional algorithms.

</DOC>
<DOC>
<DOCNO> 101165 </DOCNO>
Triple Linking of Surfaces in 4-Space


  Triple linking numbers were defined for 3-component oriented surface-links in
4-space using signed triple points on projections in 3-space. In this paper we
give an algebraic formulation using intersections of homology classes (or cup
products on cohomology groups). We prove that spherical links have trivial
triple linking numbers and that triple linking numbers are link homology
invariants.

</DOC>
<DOC>
<DOCNO> 117998 </DOCNO>
Constraining the Radio-Submm Redshift Indicator using data from the


  Many of the faint submm sources uncovered by deep SCUBA surveys still remain
unidentified at most, if not all other wavelengths. The most successful method
so far of obtaining accurate positions and hence allowing more secure
identifications has been to use centimetre wavelength imaging with the VLA.
This has led to a tempting approach for obtaining redshift estimates for this
population (Carilli & Yun 1999,2000), which relies on the tight FIR-radio
relationship and takes advantage of the steep spectral slope in the submm. In
this paper we use the submm data from the SCUBA Local Universe Galaxy Survey
(SLUGS) to estimate the usefulness of, and the uncertainties in, the
radio-submm redshift estimator. We investigate the dependencies of the
submm-radio spectral index on various galaxy properties and find that there is
no significant trend with dust temperature or 850 micron luminosity. The ratio
of 850 micron/1.4 GHz flux was found to decrease with increasing radio and FIR
luminosity, and we propose that this is due to a component of the dust not
associated with recent star formation but which is instead heated to 15-20 K by
the general interstellar radiation field.

</DOC>
<DOC>
<DOCNO> 9544 </DOCNO>
Multifractality in uniform hyperbolic lattices and in quasi-classical


  We introduce a deterministic model defined on a two dimensional hyperbolic
lattice. This model provides an example of a non random system whose
multifractal behaviour has a number theoretic origin. We determine the
multifractal exponents, discuss the termination of multifractality and
conjecture the geometric origin of the multifractal behavior in Liouville
quasi--classical field theory.

</DOC>
<DOC>
<DOCNO> 121362 </DOCNO>
The Dependence of Dynamo $\alpha$-Effect on Reynolds Numbers, Magnetic


  We generalize the derivation of dynamo coefficient $\alpha$ of Field et al
(1999) to include the following two aspects: first, the de-correlation times of
velocity field and magnetic field are different; second, the magnetic Prandtl
number can be arbitrary. We find that the contributions of velocity field and
magnetic field to the $\alpha$ effect are not equal, but affected by their
different statistical properties. In the limit of large kinetic Reynolds number
and large magnetic Reynolds number, $\alpha$-coefficient may not be small if
the de-correlation times of velocity field and magnetic field are shorter than
the eddy turn-over time of the MHD turbulence. We also show that under certain
circumstances, for example if the kinetic helicity and current helicity are
comparable, $\alpha$ depends insensitively on magnetic Prandtl number, while if
either the kinetic helicity or the current helicity is dominated by the other
one, a different magnetic Prandtl number will significantly change the dynamo
$\alpha$ effect.

</DOC>
<DOC>
<DOCNO> 151981 </DOCNO>
Instability of charged black holes in anti-de Sitter space


  We exhibit a tachyonic mode in a linearized analysis of perturbations of
large anti-de Sitter Reissner-Nordstrom black holes in four dimensions. In the
large black hole limit, and up to a 0.7% discrepancy which is probably
round-off error in the numerical analysis, the tachyon appears precisely when
the black hole becomes thermodynamically unstable.

</DOC>
<DOC>
<DOCNO> 122682 </DOCNO>
Using the 2dF galaxy redshift survey to detect gravitationally-lensed


  Galaxy redshift surveys can be used to detect gravitationally-lensed quasars
if the spectra obtained are searched for the quasars' emission lines. Previous
investigations of this possibility have used simple models to show that the 2
degree Field (2dF) redshift survey could yield several tens of new lenses, and
that the larger Sloan Digital Sky Survey should contain an order of magnitude
more. However the particular selection effects of the samples were not included
in these calculations, limiting the robustness of the predictions; thus a more
detailed simulation of the 2dF survey was undertaken here. The use of an
isophotal magnitude limit reduces both the depth of the sample and the expected
number of lenses, but more important is the Automatic Plate Measuring survey's
star-galaxy separation algorithm, used to generate the 2dF input catalogue. It
is found that most quasar lenses are classed as merged stars, with only the few
lenses with low-redshift deflectors likely to be classified as galaxies.
Explicit inclusion of these selection effects implies that the 2dF survey
should contain 10 lenses on average. The largest remaining uncertainty is the
lack of knowledge of the ease with which any underlying quasars can be
extracted from the survey spectra.

</DOC>
<DOC>
<DOCNO> 10219 </DOCNO>
CVM studies on the atomic ordering in complex perovskite alloys


  The atomic ordering in complex perovskite alloys is investigated by the
cluster variation method (CVM). For the 1/3\{111\}-type ordered structure, the
order-disorder phase transition is the first order, and the order parameter of
the 1:2 complex perovskite reaches its maximum near x=0.25. For the
1/2\{111\}-type ordered structure, the ordering transition is the second order.
Phase diagrams for both ordered structures are obtained. The order-disorder
line obeys the linear law.

</DOC>
<DOC>
<DOCNO> 100069 </DOCNO>
Motivic zeta functions of infinite dimensional Lie algebras


  We associate motivic zeta functions to a large class of infinite dimensional
Lie algebras

</DOC>
<DOC>
<DOCNO> 11548 </DOCNO>
The Luttinger model: its role in the RG-theory of one dimensional many


  The Luttinger model was introduced to illustrate the theory of Tomonaga via
an exactly soluble model. It became soon the subject of great interest also on
the part of Mathematical Physics and a key to the investigations of the
mathematical properties of Condensed Matter Physics. This paper reviews aspects
of the above developments relevant for renormalization group methods.

</DOC>
<DOC>
<DOCNO> 39642 </DOCNO>
Partial-wave analysis of the eta pi+ pi- system produced in the reaction


  A partial-wave analysis of 9082 eta pi+ pi- n events produced in the reaction
pi- p --> eta pi+ pi- n at 18.3 GeV/c has been carried out using data from
experiment 852 at Brookhaven National Laboratory. The data are dominated by
J^{PC} = 0^{-+} partial waves consistent with observation of the eta(1295) and
the eta(1440). The mass and width of the eta(1295) were determined to be 1282
+- 5 MeV and 66 +- 13 Mev respectively while the eta(1440) was observed with a
mass of 1404 +- 6 MeV and width of 80 +- 21 MeV. Other partial waves of
importance include the 1++ and the 1+- waves. Results of the partial wave
analysis are combined with results of other experiments to estimate f1(1285)
branching fractions. These values are considerably different from current
values determined without the aid of amplitude analyses.

</DOC>
<DOC>
<DOCNO> 102411 </DOCNO>
Theta-functions for indefinite polarizations


  We propose a generalization of the classical theta function to higher
cohomology of the polarization line bundle on a family of complex tori with
positive index. The constructed cocycles vary horizontally with respect to the
(projective) flat connection on this family coming from a heat operator. They
also possess modular properties similar to the classical ones.

</DOC>
<DOC>
<DOCNO> 150548 </DOCNO>
String Cosmology: The Pre-Big Bang Scenario


  A review is attempted of physical motivations, theoretical and
phenomenological aspects, as well as outstanding problems, of the pre-big bang
scenario in string cosmology.

</DOC>
<DOC>
<DOCNO> 100344 </DOCNO>
On toric varieties and algebraic semigroups


  The main result of this paper is that every (separated) toric variety which
has a semigroup structure compatible with multiplication on the underlying
torus is necessarily affine. In the course of proving this statement, we also
give a proof of the fact that every separated toric variety may be constructed
from a certain fan in a Euclidean space. To our best knowledge, this proof
differs essentially from the ones which can be found in the literature.

</DOC>
<DOC>
<DOCNO> 116970 </DOCNO>
Development of the 50-Mev DTL for the Jaeri/Kek Joint Project


  An Alvaretz-type DTL, to accelerate the H- ion beam from 3 to 50 MeV, is
being constructed as the injector for the JAERI/KEK Joint Project. The
following components of the DTL have been developed: (1) a cylindrical tank,
made by copper electroforming; (2) rf contactors; (3) a pulse-excited
quadrupole magnet with a hollow coil made by copper electroforming; (4) a
switching-regulator-type pulsed-power supply for the quadrupole magnet.
High-power tests of the components have been conducted using a short-model
tank. Moreover a breakdown experiment of the copper electrodes has been carried
out in order to study the properties of several kinds of copper materials.

</DOC>
<DOC>
<DOCNO> 178543 </DOCNO>
Is the analysis of flow at the CERN SPS reliable?


  Several heavy ion experiments at SPS have measured azimuthal distributions of
particles with respect to the reaction plane. These distributions are deduced
from two-particle azimuthal correlations under the assumption that they result
solely from correlations with the reaction plane. In this paper, we investigate
other sources of azimuthal correlations: transverse momentum conservation,
which produces back-to-back correlations, resonance decays, HBT correlations
and final state interactions. These correlations increase with impact
parameter: most of them vary with the multiplicity N like 1/N. When they are
taken into account, the experimental results of the NA49 collaboration at SPS
are significantly modified. These correlations might also explain an important
fraction of the pion directed flow observed by WA98. Data should be reanalyzed
taking into account carefully these non--flow correlations.

</DOC>
<DOC>
<DOCNO> 117728 </DOCNO>
The Magnetic Fields of the Universe and Their Origin


  Recent rotation measure observations of a dozen or so galaxy clusters have
revealed a surprisingly large amount of magnetic fields, whose estimated energy
and flux are, on average, $\sim 10^{58}$ ergs and $\sim 10^{41}$ G cm$^2$,
respectively. These quantities are so much larger than any coherent sums of
individual galaxies within the cluster that an efficient galactic dynamo is
required. We associate these fields with single AGNs within the cluster and
therefore with all galaxies during their AGN phase. Only the central, massive
black hole (BH) has the necessary binding energy, $\sim 10^{61}$ ergs. Only the
accretion disk during the BH formation has the winding number, $\sim 10^{11}$
turns, necessary to make the gain and magnetic flux. We present a model of the
BH accretion disk dynamo that might create these magnetic fields, where the
helicity of the $\alpha - \Omega$ dynamo is driven by star-disk collisions. The
back reaction of the saturated dynamo forms a force-free field helix that
carries the energy and flux of the dynamo and redistributes them within the
clusters.

</DOC>
<DOC>
<DOCNO> 178910 </DOCNO>
Effective Field Theory in Nuclear Many-Body Physics


  Recent progress in Lorentz-covariant quantum field theories of the nuclear
many-body problem (quantum hadrodynamics, or QHD) is discussed. The importance
of modern perspectives in effective field theory and density functional theory
for understanding the successes of QHD is emphasized.
  To appear in: 150 Years of Quantum Many-Body Theory: A conference in honour
of the 65th birthdays of John W. Clark, Alpo J. Kallio, Manfred L. Ristig, and
Sergio Rosati.

</DOC>
<DOC>
<DOCNO> 13337 </DOCNO>
Re-entrant ferroelectricity in liquid crystals


  The ferroelectric (Sm C$^*$) -- antiferroelectric (Sm C$^*_A$) -- reentrant
ferroelectric (re Sm C$^*$) phase temperature sequence was observed for system
with competing synclinic - anticlinic interactions. The basic properties of
this system are as follows (1) the Sm C$^*$ phase is metastable in temperature
range of the Sm C$^*_A$ stability (2) the double inversions of the helix
handedness at Sm C$^*$ -- Sm C$^*_A$ and Sm C$^*_A$% -- re-Sm C$^*$ phase
transitions were found (3) the threshold electric field that is necessary to
induce synclinic ordering in the Sm C$^*_A$ phase decreases near both Sm
C$^*_A$ -- Sm C$^*$ and Sm C$^*_A$ -- re-Sm C$^*$ phase boundaries, and it has
maximum in the middle of the Sm C$^*_A$ stability region. All these properties
are properly described by simple Landau model that accounts for nearest
neighboring layer steric interactions and quadrupolar ordering only.

</DOC>
<DOC>
<DOCNO> 151036 </DOCNO>
String Theory Duals for Mass-deformed SO(N) and USp(2N) N=4 SYM Theories


  We generalize the results of Polchinski and Strassler regarding the
N=1-preserving mass deformation of N=4 SU(N) SYM theories and its string theory
dual to SO(N) and USp(2N) gauge groups. The string theory duals involve
5-branes wrapped on RP^2. In order to match with the field theory
classification of vacua, the 3-brane charge carried by such 5-branes must be
shifted by a half, and this follows from a conjectured generalization of
results of Freed and Witten. Our results provide an elegant physical picture
for the classification of classically massive vacua in the mass-deformed N=4
theories.

</DOC>
<DOC>
<DOCNO> 119105 </DOCNO>
Far Infrared Study of IRAS 00494+5617 & IRAS 05327-0457


  High angular resolution far-infrared observations at 143 & 185 \micron, using
the TIFR 1-m balloon borne telescope, are presented for two Galactic star
forming complexes associated with IRAS 00494+5617 and 05327-0457. The latter
map also reveals the cold dust in OMC-3. The HIRES processed IRAS maps at 12,
25, 60 & 100 micron have also been presented for comparison. Both these regions
are illuminated at the edges by high mass stars with substantial UV flux.The
present study is aimed at quantifying the role of the nearby stars vis-a-vis
embedded young stellar objects in the overall heating of these sources. Based
on the FIR observations at 143 & 185 micron carried out simultaneously with
almost identical angular resolution, reliable dust temperature and optical
depth maps have been generated for the brighter regions of these sources.
Radiative transfer modeling in spherical geometry has been carried out to
extract physical parameters of these sources by considering the observational
constraints like : spectral energy distribution, angular size at different
wavelengths, dust temperature distribution etc. It has been concluded that for
both IRAS 00494+5617 and IRAS 05327-0457, the embedded energy sources play the
major role in heating them with finite contribution from the nearby stars. The
best fit model for IRAS 00494+5617 is consistent with a simple two phase
clump-interclump picture with $\sim$ 5% volume filling factor (of clumps) and a
density contrast of $\approx$ 80.

</DOC>
<DOC>
<DOCNO> 84444 </DOCNO>
Triad representation of the Chern-Simons state in quantum gravity


  We investigate a triad representation of the Chern-Simons state of quantum
gravity with a non-vanishing cosmological constant. It is shown that the
Chern-Simons state, which is a well-known exact wavefunctional within the
Ashtekar theory, can be transformed to the real triad representation by means
of a suitably generalized Fourier transformation, yielding a complex integral
representation for the corresponding state in the triad variables. It is found
that topologically inequivalent choices for the complex integration contour
give rise to linearly independent wavefunctionals in the triad representation,
which all arise from the one Chern-Simons state in the Ashtekar variables. For
a suitable choice of the normalization factor, these states turn out to be
gauge-invariant under arbitrary, even topologically non-trivial
gauge-transformations. Explicit analytical expressions for the wavefunctionals
in the triad representation can be obtained in several interesting asymptotic
parameter regimes, and the associated semiclassical 4-geometries are discussed.
In restriction to Bianchi-type homogeneous 3-metrics, we compare our results
with earlier discussions of homogeneous cosmological models. Moreover, we
define an inner product on the Hilbert space of quantum gravity, and choose a
natural gauge-condition fixing the time-gauge. With respect to this particular
inner product, the Chern-Simons state of quantum gravity turns out to be a
non-normalizable wavefunctional.

</DOC>
<DOC>
<DOCNO> 11115 </DOCNO>
Squeezing and entanglement of atomic beams


  We propose and analyze a scheme for generating entangled atomic beams out of
a Bose-Einstein condensate using spin-exchanging collisions. In particular, we
show how to create both atomic squeezed states and entangled states of pairs of
atoms.

</DOC>
<DOC>
<DOCNO> 71165 </DOCNO>
Lepton Flavor Violation in the Two Higgs Doublet Model type III


  We consider the Two Higgs Doublet Model (2HDM) of type III which leads to
Flavour Changing Neutral Currents (FCNC) at tree level in the leptonic sector.
In the framework of this model we can have, in principle, two situations: the
case (a) when both doublets acquire a vacuum expectation value different from
zero and the case (b) when only one of them is not zero. In addition, we show
that we can make two types of rotations for the flavor mixing matrices which
generates four types of lagrangians, with the rotation of type I we recover the
case (b) from the case (a) in the limit $\tan \beta \to \infty $, and with the
rotation of type II we obtain the case (b) from (a) in the limit $\tan \beta
\to 0. $Moreover, two of the four possible lagrangians correspond to the models
of types I and II plus Flavor Changing (FC) interactions. The analitical
expressions of the partial lepton number violating widths $\Gamma (\mu \to eee)
$ and $\Gamma (\mu \to e\gamma) $are derived for the cases (a) and (b) and both
types of rotations.$ $In all cases these widths go asymptotically to zero in
the decoupling limit for all Higgses. We present from our analysis upper bounds
for the flavour changing transition $\mu \to e,$ and we show that such bounds
are sensitive to the VEV structure and the type of rotation utilized.

</DOC>
<DOC>
<DOCNO> 13741 </DOCNO>
Comment on "Negative heat ..." by Moretto et al


  The recent paper nucl-th/0012037 by Moretto et al. is commented

</DOC>
<DOC>
<DOCNO> 68097 </DOCNO>
Temperature, chemical potential and the rho meson


  We describe some applications of the Dyson-Schwinger equations at
nonzero-(T,mu). Employing a simple model dressed-gluon propagator we determine
the boundary of the deconfinement phase transition and the medium dependence of
rho-meson properties. We introduce an extension to describe the time-evolution
of scalar and vector self energies.

</DOC>
<DOC>
<DOCNO> 123310 </DOCNO>
Jets and Outflows From Advective Accretion Disks


  Jets and outflows must be produced directly from accretion disks and inflows,
especially when the central gravitating objects are compact, such as neutron
stars and black holes, and themselves are {\it not} mass losing. Here, we
review the formation of jets from advective inflows. We show that the
centrifugal pressure supported boundary layer (CENBOL) of the black holes may
play crucial role in producing outflows. CENBOL is not present in Keplerian
disks. Thus energetic jet formation is directly connected to sub-Keplerian
flows close to compact objects.

</DOC>
<DOC>
<DOCNO> 85623 </DOCNO>
The close limit from a null point of view: the advanced solution


  We present a characteristic algorithm for computing the perturbation of a
Schwarzschild spacetime by means of solving the Teukolsky equation. We
implement the algorithm as a characteristic evolution code and apply it to
compute the advanced solution to a black hole collision in the close
approximation. The code successfully tracks the initial burst and quasinormal
decay of a black hole perturbation through 10 orders of magnitude and tracks
the final power law decay through an additional 6 orders of magnitude.
Determination of the advanced solution, in which ingoing radiation is absorbed
by the black hole but no outgoing radiation is emitted, is the first stage of a
two stage approach to determining the retarded solution, which provides the
close approximation waveform with the physically appropriate boundary condition
of no ingoing radiation.

</DOC>
<DOC>
<DOCNO> 170236 </DOCNO>
Relativistic J-matrix method


  The relativistic version of the J-matrix method for a scattering problem on
the potential vanishing faster than the Coulomb one is formulated. As in the
non-relativistic case it leads to a finite algebraic eigenvalue problem. The
derived expression for the tangent of phase shift is simply related to the
non-relativistic case formula and gives the latter as a limit case. It is due
to the fact that the used basis set satisfies the ``kinetic balance
condition''.

</DOC>
<DOC>
<DOCNO> 67943 </DOCNO>
Lambda polarization and single-spin left-right asymmetry in diffractive


  We discuss Lambda polarization and single-spin left-right asymmetry in
diffractive hadron-hadron scattering at high energies. We show that the
physical picture proposed in a recent Letter is consistent with the
experimental observation that $\Lambda$ polarization in the diffractive
process, $pp\to \Lambda K^+p$, is much higher than that in the inclusive
reaction, $pp\to \Lambda X$. We make predictions for the left-right asymmetry,
A_N, and for the spin transfer, $D_{NN}^\Lambda$, in the single-spin process
$p(\uparrow)p\to \Lambda K^+p$ and suggest further experimental tests of the
proposed picture.

</DOC>
<DOC>
<DOCNO> 102174 </DOCNO>
An example of a non acyclic Koszul complex of a module


  In his paper "Residues of a Pfaff system relative to an invariant subscheme"
in Trans. Amer. Math. Soc. 352, 2000, 4019-4035, F. Sancho de Salas defines the
universal Koszul complex of a module $M$ over a sheaf of rings $\mathcal{O}$ as
${\rm Kos}(M)=\Lambda (M)\otimes_{\mathcal{O}}S(M)$, where $\Lambda (M)$ and
$S(M)$ stand for the exterior and symmetric algebras of $M$, endowed with the
usual differential, and he conjectures (Conjecture 2.3.) that ${\rm Kos}(M)$ is
always acyclic. We give here an example of a non acyclic Koszul complex ${\rm
Kos}(M)$.

</DOC>
<DOC>
<DOCNO> 99634 </DOCNO>
Linear Odd Poisson Bracket on Grassmann Algebra


  A linear odd Poisson bracket realized solely in terms of Grassmann variables
is suggested. It is revealed that with the bracket, corresponding to a
semi-simple Lie group, both a Grassmann-odd Casimir function and invariant
(with respect to this group) nilpotent differential operators of the first,
second and third orders are naturally related and enter into a
finite-dimensional Lie superalgebra. A connection of the quantities, forming
this Lie superalgebra, with the BRST charge, $\Delta$-operator and ghost number
operator is indicated.

</DOC>
<DOC>
<DOCNO> 83315 </DOCNO>
A theory of normed simulations


  In existing simulation proof techniques, a single step in a lower-level
specification may be simulated by an extended execution fragment in a
higher-level one. As a result, it is cumbersome to mechanize these techniques
using general purpose theorem provers. Moreover, it is undecidable whether a
given relation is a simulation, even if tautology checking is decidable for the
underlying specification logic. This paper introduces various types of normed
simulations. In a normed simulation, each step in a lower-level specification
can be simulated by at most one step in the higher-level one, for any related
pair of states. We show that, under some reasonable assumptions, it is
decidable whether a given relation is a normed forward simulation, provided
tautology checking is decidable for the underlying logic. We also prove that,
at the semantic level, normed forward and backward simulations together form a
complete proof method for establishing behavior inclusion, provided that the
higher-level specification has finite invisible nondeterminism. Apart from
their pleasant theoretical properties, normed simulations also have turned out
to be quite useful as a vehicle for the formalization of refinement proofs via
theorem provers.

</DOC>
<DOC>
<DOCNO> 118216 </DOCNO>
Electron Acceleration and Time Variability of High Energy Emission from


  Blazars are known to emit a broad band emission from radio to gamma-rays with
rapid time variations, particularly, in X- and gamma-rays. Synchrotron
radiation and inverse Compton scattering are thought to play an important role
in emission and the time variations are likely related to the acceleration of
nonthermal electrons. As simultaneous multiwavelength observations with
continuous time spans are recently available, some characteristics of electron
acceleration are possibly inferred from the spectral changes of high energy
emission. In order to make such inferences, we solve the time-dependent kinetic
equations of electrons and photons simultaneously using a simple model for
electron acceleration. We then show how the time variations of emission are
dependent on electron acceleration. We also present a simple model for a flare
in X-rays and TeV gamma-rays by temporarily changing the acceleration
timescale. Our model will be used, in future, to analyze observed data in
detail to obtain information on electron acceleration in blazars.

</DOC>
<DOC>
<DOCNO> 11751 </DOCNO>
Asymmetric shape and dynamic stability of exciton-phonon solitons moving


  Solitons are known to move ballistically through a medium without changement
of their shape. In practice, the shape of moving inhomogeneous states changes,
and a long lasting tail appears behind the soliton moving in a periodic medium.
Such a behavior can be described within the model of exciton-phonon coherent
states as a dynamic effect in soliton transport. We argue that the coupling
between bosonic excitations of the medium, such as excitons, and elastic modes
of it, such as phonons, can be responsible for these effects in Condensed
Matter Physics. We derive nonlinear dynamic equations for the excited medium in
the long wavelength approximation (a generalized Zakharov system) and apply a
kind of ballistic ansatz for the coherent state of bosons and displacement
field. The total packet can be associated with an exciton-phonon comet with the
quasistable coherent Bose-core and incoherent tail moving in the medium.

</DOC>
<DOC>
<DOCNO> 122919 </DOCNO>
BeppoSAX confirmation of beamed afterglow emission from GRB990510


  We compare the prompt X-ray (2-10 keV) emission of GRB990510 measured by the
BeppoSAX Wide Field Cameras (WFC) during the burst to the X-ray afterglow
detected by the BeppoSAX Narrow Field Instruments. A single power-law model for
the afterglow, f(t) ~ t^{-1.42}, is ruled out. Provided the initial time of the
afterglow is assumed to coincide with the last short pulse in the X-ray prompt
event (i.e., 72 seconds after the GRB trigger time), the X-ray emission from
\~80 to 10^5 seconds after the GRB trigger is well described by an external
shock expanding in a decelerating jet, in which synchrotron radiation takes
place. This model, represented by a double power-law of indices alpha_1 ~ 1 and
alpha_2 ~ 2 before and after a jet collimation break time of ~0.5 days after
GRB, respectively, is consistent with the second and third upper limits
measured by the WFC, but not with the first. This may be related to
inhomogeneities in the circumburst medium. Our finding indicates that the
temporal behavior of the GRB990510 X-ray afterglow is similar to that at
optical wavelengths, and thus strengthens the interpretation of the
multiwavelength afterglow as synchrotron emission in a jet with decreasing
Lorentz factor. GRB990510 is thus the only burst in which evidence of a
spreading jet has been found in X-rays.

</DOC>
<DOC>
<DOCNO> 120095 </DOCNO>
HI absorption in radio galaxies


  Twenty-two powerful radio galaxies have been searched for HI absorption. We
find the highest probability of detecting HI in absorption among narrow-line
compact (or small) galaxies or galaxies with indication of richer interstellar
medium (i.e. with ongoing or recent star-formation). We discuss the difficulty
in the interpretation of the origin of the HI absorption due to the uncertainty
in the systemic velocity of the galaxies.

</DOC>
<DOC>
<DOCNO> 117451 </DOCNO>
EUV and X-ray observation of Abell 2199: a three-phase intracluster


  Various independent ways of constraining the Hubble constant and the baryonic
content of the universe finally converged at a consensus range of values which
indicates that at the present epoch the bulk of the universe's baryons is in
the form of a warm $\sim$ 10$^6$ K gas - a temperature regime which renders
them difficult to detect. The discovery of EUV and soft X-ray excess emission
from clusters of galaxies was originally interpreted as the first direct
evidence for the large scale presence of such a warm component. We present
results from an EUVE Deep Survey (DS) observation of the rich cluster Abell
2199 in the Lex/B (69 - 190 eV) filter passband. The soft excess radial trend
(SERT), shown by a plot against cluster radius $r$ of the percentage EUV
emission $\eta$ observed above the level expected from the hot intracluster
medium (ICM), reveals that $\eta$ is a simple function of $r$ which decreases
monotonically towards $r = 0$; it smoothly turns negative at $r \sim$ 6 arcmin,
inwards of this radius the EUV is absorbed by cold matter with a line-of-sight
column density of $\geq$ 2.7 $\times$ 10$^{19}$ cm$^{-2}$. The area of
absorption is much larger than that of the cooling flow. These facts together
provide strong evidence for a centrally concentrated but cluster-wide
distribution of clumps of cold gas which co-exist with warm gas of similar
spatial properties. Further, the simultaneous modeling of EUV and X-ray data
requires a warm component even within the region of absorption. The phenomenon
demonstrates a three phase ICM, with the warm phase estimated to be $\sim$ 5-10
times more massive than the hot.

</DOC>
<DOC>
<DOCNO> 68757 </DOCNO>
Reply to Boglione and Pennington


  In a recent article we presented an argument which, we believe, shows to be
incorrect an estimate, by Boglione and Pennington, of corrections to the
valence (quenched) approximation predictions for properties of the lightest
scalar glueball. Boglione and Pennington's reply to our article, it appears to
us, fails to address the specific technical issues we raised.

</DOC>
<DOC>
<DOCNO> 117911 </DOCNO>
Color-Magnitude Sequence in the Clusters at z$\sim$1.2 near the Radio


  We have investigated the optical and near-infrared colors of K'-selected
galaxies in clusters at z ~ 1.2 near to the radio galaxy 3C 324 using images
obtained with the Subaru telescope and archival HST data. The distribution of
colors of the galaxies in the cluster region is found to be fairly broad, and
it may imply significant scatter in their star-formation histories, although
the effect of contamination of field galaxies is uncertain. The red sequence of
galaxies whose R-K colors are consistent with passive evolution models for old
galaxies is found to be truncated at K' ~ 20 mag, and there are few fainter
galaxies with similar red colors in the cluster region. We find that the
bulge-dominated galaxies selected by quantitative morphological classification
form a broad sequence in the color-magnitude diagram, whose slope is much
steeper than that expected from metallicity variations within a passively
evolving coeval galaxy population. We argue that the observed color-magnitude
sequence can be explained by metallicity and age variations, and the fainter
galaxies with K' > 20 mag may be 1-2 Gyr younger than the brighter galaxies.
Some spatial segregation of the color and K'-band luminosity is seen in the sky
distribution; the redder and the brighter objects tend to be located near 3C
324.

</DOC>
<DOC>
<DOCNO> 71842 </DOCNO>
The Landau Pole at Finite Temperature


  We study the Landau pole in the lambda phi^4 field theory at non-zero and
large temperatures. We show that the position of the thermal Landau pole
Lambda_L(T) is shifted to higher energies with respect to the zero temperature
Landau pole Lambda_L(0). We find for high temperatures T > Lambda_L(0),
Lambda_L(T) simeq pi^2 T / log (T / Lambda_L(0)). Therefore, the range of
applicability in energy of the lambda phi^4 field theory increases with the
temperature.

</DOC>
<DOC>
<DOCNO> 150667 </DOCNO>
Branes at Angles and Resolution of Orbifold Singularities


  This paper has been withdrawn.

</DOC>
<DOC>
<DOCNO> 117187 </DOCNO>
Design and optimization of tapered structure of near-field fiber probe


  The finite-difference time-domain method was employed to simulate light
propagation in tapered near-field fiber probes with small metal aperture. By
conducting large-volume simulations, including tapered metal-cladding waveguide
and connected optical fiber waveguide, we illustrated the coupling between
these guiding modes as well as the electric field distribution in the vicinity
of the aperture. The high collection efficiency of a double-tapered probe was
reproduced and was ascribed to the shortening of the cutoff region and the
efficient coupling to the guiding mode of the optical fiber. The dependence of
the efficiency on the tapered structure parameters was also examined.

</DOC>
<DOC>
<DOCNO> 85631 </DOCNO>
Exact late time Hawking radiation and the information loss problem for


  In this paper we investigate the effects of gravitational backreaction for
the late time Hawking radiation of evaporating near-extremal black holes. This
problem can be studied within the framework of an effective one-loop solvable
model on AdS_2. We find that the Hawking flux goes down exponentially and it is
proportional to a parameter which depends on details of the collapsing matter.
This result seems to suggest that the information of the initial state is not
lost and that the boundary of AdS_2 acts, at least at late times, as a sort of
stretched horizon in the Reissner-Nordstrom spacetime.

</DOC>
<DOC>
<DOCNO> 100119 </DOCNO>
Weyl Modules for Classical and Quantum Affine algebras


  We define a family of universal finite-dimensional highest weight modules for
affine Lie algebras, we call these Weyl modules. We conjecture that these are
the classical limits of the irreducible finite--dimensional representations of
the quantum affine algebras. We prove this conjecture in the case of affine
sl_2. We establish a criterion for these modules to be irreducible and prove a
factorization theorem for them in the general case.

</DOC>
<DOC>
<DOCNO> 71028 </DOCNO>
A Note on the Gauge Group of the Electroweak Interactions


  We propose a three-fold covering of the group ${U}(2)$ as a gauge group for
the electroweak interactions for the purpose of describing fields with integer
and fractional electric charges with respect to the residual electromagnetic
gauge group after a spontaneous breaking of the gauge symmetry. In a more
general scheme we construct a three-fold covering of ${U} (n)$ and consider for
the case $n=2$ several representations which are used in the construction of a
model of the electroweak interactions in a subsequent paper.

</DOC>
<DOC>
<DOCNO> 10489 </DOCNO>
Identification of the Orbital Pairing Symmetry in UPt_3


  This paper summarizes the results of a comprehensive analysis of the
thermodynamic and transport data for the superconducting phases of UPt_3.
Calculations of the transverse sound attenuation as a function of temperature,
frequency, polarization, and disorder are presented for the leading models of
the superconducting order parameter. Measurements of the specific heat, thermal
conductivity, and transverse sound attenuation place strong constraints on the
orbital symmetry of the superconducting order parameter. We show that the
superconducting A and B phases are in excellent agreement with pairing states
belonging to the odd-parity E_{2u} orbital representation.

</DOC>
<DOC>
<DOCNO> 151389 </DOCNO>
Gauge Theory on a Quantum Phase Space


  In this note we present a operator formulation of gauge theories in a quantum
phase space which is specified by a operator algebra. For simplicity we work
with the Heisenberg algebra. We introduce the notion of the derivative
(transport) and Wilson line (parallel transport) which enables us to construct
a gauge theory in a simple way. We illustrate the formulation by a discussion
of the Higgs mechanism and comment on the large N masterfield.

</DOC>
<DOC>
<DOCNO> 116657 </DOCNO>
Modeling study on the validity of a possibly simplified representation


  The folding characteristics of sequences reduced with a possibly simplified
representation of five types of residues are shown to be similar to their
original ones with the natural set of residues (20 types or 20 letters). The
reduced sequences have a good foldability and fold to the same native structure
of their optimized original ones. A large ground state gap for the native
structure shows the thermodynamic stability of the reduced sequences. The
general validity of such a five-letter reduction is further studied via the
correlation between the reduced sequences and the original ones. As a
comparison, a reduction with two letters is found not to reproduce the native
structure of the original sequences due to its homopolymeric features.

</DOC>
<DOC>
<DOCNO> 121751 </DOCNO>
Why the Salpeter screening formula cannot be applied in the Sun


  In a recent paper, Bahcall et al. (2000) list various new approaches to the
problem of screening of nuclear reactions in stellar plasma and assert that
they are all wrong or irrelevant. Except for two, all approaches mentioned by
Bahcall et al. assume the mean field approximation. The two exceptions are
Carraro et al. (1988) and Shaviv & Shaviv (2000a). While Carraro et al. (1988)
paper is discussed shortly and refuted by Bahcall et al. (2000) the Shaviv &
Shaviv (2000a) paper is not discussed and refuted only by association. However,
the association is totally unfounded because Shaviv & Shaviv (2000a) have shown
that kinetic equations must be used to solve the screening problem and that the
mean field approximation is inadequate for this problem. They also showed that
the Carraro et al. (1988) approach is erroneous.
  Therefore we summarize here the method of $S^{2}$ and their main result.
  We contrast the kinetic equations method with the mean field approximation
and expose the different assumptions and omissions in each method.

</DOC>
<DOC>
<DOCNO> 170190 </DOCNO>
Quantum coherence and interaction-free measurements


  We investigate the extent to which ``interaction-free'' measurements perturb
the state of quantum systems. We show that the absence of energy exchange
during the measurement is not a sufficient criterion to preserve that state, as
the quantum system is subject to measurement dependent decoherence. While it is
possible in general to design interaction-free measurement schemes that do
preserve that state, the requirement of quantum coherence preservation rapidly
leads to a very low efficiency. Our results, which have a simple interpretation
in terms of ``which-way'' arguments, open up the way to novel quantum
non-demolition techniques.

</DOC>
<DOC>
<DOCNO> 150500 </DOCNO>
A note on the analyticity of AdS scalar exchange graphs in the crossed


  We discuss the analytic properties of AdS scalar exchange graphs in the
crossed channel. We show that the possible non-analytic terms drop out by
virtue of non-trivial properties of generalized hypergeometric functions. The
absence of non-analytic terms is a necessary condition for the existence of an
operator product expansion for CFT amplitudes obtained from AdS/CFT
correspondence.

</DOC>
<DOC>
<DOCNO> 121709 </DOCNO>
Dynamical Evolution of Clusters


  We consider a sample of about 50 distant galaxy clusters at z>0.15 (<z> about
0.3), each cluster having at least 10 galaxies with available redshift in the
literature. We select member galaxies, analyze the velocity dispersion
profiles, and evaluate in a homogeneous way cluster velocity dispersions and
virial masses. We apply the same procedures already recently applied on a
sample of nearby clusters (z<0.15) in order to properly analyze the possible
dynamical evolution of galaxy clusters. We do not find any significant
difference between nearby and distant clusters. In particular, we consider the
galaxy spatial distribution, the shape of the velocity dispersion profile, and
the relations between velocity dispersion and X-ray luminosity and temperature.
Our results imply little dynamical evolution in the range of redshift spanned
by our cluster sample, and suggest that the typical redshift of cluster
formation is higher than that of the sample we analyze.

</DOC>
<DOC>
<DOCNO> 119111 </DOCNO>
Evidence for a Black Hole and Accretion Disk in the LINER NGC 4203


  We present spectroscopic observations from the Hubble Space Telescope that
reveal for the first time the presence of a broad pedestal of Balmer-line
emission in the LINER galaxy NGC 4203. The emission-line profile is suggestive
of a relativistic accretion disk, and is reminiscent of double-peaked transient
Balmer emission observed in a handful of other LINERs. The very broad line
emission thus constitutes clear qualitative evidence for a black hole, and
spatially resolved narrow-line emission in NGC 4203 can be used to constrain
its mass, with M_BH less than 6 x 10^6 solar masses at 99.7% confidence. This
value implies a ratio of black-hole mass to bulge mass of less than
approximately 7 x 10^-4 in NGC 4203, which is less by a factor of ~3 - 9 than
the mean ratio obtained for other galaxies. The availability of an independent
constraint on central black-hole mass makes NGC4203 an important testbed for
probing the physics of weak active galactic nuclei. Assuming M_BH near the
detection limit, the ratio of observed luminosity to the Eddington luminosity
is approximately 10^-4. This value is consistent with advection-dominated
accretion, and hence with scenarios in which an ion torus irradiates an outer
accretion disk that produces the observed double-peaked line emission.
Follow-up observations will make it possible to improve the black-hole mass
estimate and study variability in the nuclear emission.

</DOC>
<DOC>
<DOCNO> 120798 </DOCNO>
Observational Constraints on Higher Order Clustering up to $z\simeq 1


  Constraints on the validity of the hierarchical gravitational instability
theory and the evolution of biasing are presented based upon measurements of
higher order clustering statistics in the Deeprange Survey, a catalog of
$\sim710,000$ galaxies with $I_{AB} \le 24$ derived from a KPNO 4m CCD imaging
survey of a contiguous $4^{\circ} \times 4^{\circ}$ region. We compute the
3-point and 4-point angular correlation functions using a direct estimation for
the former and the counts-in-cells technique for both. The skewness $s_3$
decreases by a factor of $\simeq 3-4$ as galaxy magnitude increases over the
range $17 \le I \le 22.5$ ($0.1 \lesssim z \lesssim 0.8$). This decrease is
consistent with a small {\it increase} of the bias with increasing redshift,
but not by more than a factor of 2 for the highest redshifts probed. Our
results are strongly inconsistent, at about the $3.5-4 \sigma$ level, with
typical cosmic string models in which the initial perturbations follow a
non-Gaussian distribution - such models generally predict an opposite trend in
the degree of bias as a function of redshift. We also find that the scaling
relation between the 3-point and 4-point correlation functions remains
approximately invariant over the above magnitude range. The simplest model that
is consistent with these constraints is a universe in which an initially
Gaussian perturbation spectrum evolves under the influence of gravity combined
with a low level of bias between the matter and the galaxies that decreases
slightly from $z \sim 0.8$ to the current epoch.

</DOC>
<DOC>
<DOCNO> 69345 </DOCNO>
Neutrino Masses and the Gluino Axion Model


  We extend the recently proposed gluino axion model to include neutrino
masses. We discuss how the canonical seesaw model and the Higgs triplet model
may be realized in this framework. In the former case, the heavy singlet
neutrinos are contained in superfields which do not have any vacuum expectation
value, whereas the gluino axion is contained in one which does. We also
construct a specific renormalizable model which realizes the mass scale
relationship $M_{SUSY} \sim f_a^2/M_U$, where $f_a$ is the axion decay constant
and $M_U$ is a large effective mass parameter.

</DOC>
<DOC>
<DOCNO> 122824 </DOCNO>
Can all breaks in GRB afterglows be explained by jet effects?


  Whether gamma-ray bursts are highly beamed or not is a very important
question, since it has been pointed out that the beaming will lead to a sharp
break in the afterglow light curves during the ultra-relativistic phase, with
the breaking point determined by $\Gamma \sim 1/\theta_{0}$, where $\Gamma$ is
the bulk Lorentz factor and $\theta_{0}$ is the initial half opening angle of
the ejecta, and such a break is claimed to be present in the light curves of
some GRBs. In this paper we will examine whether all the observed breaks in GRB
afterglow light curves can be explained by jet effects. Here we present a
detailed calculation of the jet evolution and emission, and have obtained a
simple formula of bulk Lorentz factor evolution. We show that the light curves
are very smoothly steepened by jet effect, and the shape of the light curve is
determined by only one parameter -- $(E/n)^{1/8} \theta_{0}^{3/4}$, where E and
n are the fireball energy and surrounding medium density. We find that for
GRB990123 and GRB991216, the jet model can approximately fit their light
curves, and the values of $(E_{51}/n_1)^{1/8} \theta_{0}^{3/4}$ are about 0.17
and 0.22 respectively. While for GRB990510, GRB000301c, GRB000926 and
GRB010222, their light curves cannot be fitted by the jet model, which suggests
that the breaks may be caused by some other reasons, jet should be not the
unique reason.

</DOC>
<DOC>
<DOCNO> 68397 </DOCNO>
Preheating of massive fermions after inflation: analytical results


  Non-perturbative production of fermions after chaotic inflation has been the
object of several studies in the very recent past. However, the results in the
most interesting case of production of massive fermions in an expanding
Universe were so far known only numerically. We provide very simple and
readable analytical formulae, both for the spectra of the created fermions and
for their total energy density. Their derivation is closely related to the one
adopted for bosons and exploits the fact that the production occurs during very
short intervals of nonadiabatical change of the fermionic frequency. Our
formulae show the presence of resonance bands if the expansion of the Universe
is neglected, and their disappearance when the latter is included. As in the
bosonic case, this last effect is due to the stochastic character that the
expansion gives to the whole process. Backreaction is considered in the last
part of the work. All our analytical results are in excellent agreement with
the previous numerical ones in the regime of validity of the latter. However, a
more accurate scaling for the energy density of the produced fermions is here
found.

</DOC>
<DOC>
<DOCNO> 71701 </DOCNO>
Pomeron intercept from BFKL gluon dynamics in deep inelastic charm


  In the framework of semihard (k$_T$ factorization) QCD approach, we consider
the differential cross sections of $D^{*\pm}$ meson production at HERA. The
consideration is based on BFKL and CCFM gluon distributions. We find that in
the case of BFKL LO gluon distribution the theoretical results are sensitive to
the Pomeron intercept parameter $\Delta$. We present a comparison of the
theoretical results with available ZEUS experimental data.

</DOC>
<DOC>
<DOCNO> 151260 </DOCNO>
An exceptional geometry for d=11 supergravity?


  We analyze the algebraic constraints of the generalized vielbein in SO(1,2) x
SO(16) invariant d=11 supergravity, and show that the bosonic degrees of
freedom of d=11 supergravity, which become the physical ones upon reduction to
d=3, can be assembled into an E_8-valued vielbein already in eleven dimensions.
A crucial role in the construction is played by the maximal nilpotent commuting
subalgebra of E_8, of dimension 36, suggesting a partial unification of general
coordinate and tensor gauge transformations.

</DOC>
<DOC>
<DOCNO> 121613 </DOCNO>
The Temperature of Nonspherical Circumstellar Dust Grains


  The temperatures of prolate and oblate spheroidal dust grains in the
envelopes of stars of various spectral types are calculated. Homogeneous
particles with aspect ratios {\small $a/b \le 10$} composed of amorphous
carbon, iron, dirty ice, various silicates, and other materials are considered.
The temperatures of spherical and spheroidal particles were found to vary
similarly with particle size, distance to the star, and stellar temperature.
The temperature ratio {\small $T_{\rm d}({\rm spheroid})/T_{\rm d}({\rm
sphere}) $} depends most strongly on the grain chemical composition and shape.
Spheroidal grains are generally colder than spherical particles of the same
volume; only iron spheroids can be slightly hotter than iron spheres. At
{\small $a/b \approx 2$}, the temperature differences do not exceed 10 %. If
{\small $a/b \ga 4$}, the temperatures can differ by 30-40 %. For a fixed dust
mass in the medium, the fluxes at wavelengths {\small $\lambda \ga 100 \mkm$}
are higher if the grains are nonspherical, which gives over estimated dust
masses from millimeter observations. The effect of grain shape should also be
taken into account when modeling Galactic-dust emission properties, which are
calculated when searching for fluctuations of the cosmic microwave background
radiation in its Wien wing.

</DOC>
<DOC>
<DOCNO> 71890 </DOCNO>
On the reactions p + p -> p + Lambda + K^+ and p + p -> p + Sigma^0 +


  The cross sections for the reactions of the strange production p + p -> p +
Lambda + K^+ and p + p -> p + Sigma^0 + K^+ near thresholds of the final states
p Lambda K^+ and p Sigma^0 K^+ are calculated in the effective Lagrangian
approach. Our approach is based on the dominant contribution of the one-pion
exchange and strong interaction of the colliding protons in the initial state.
The theoretical values of the cross sections agree reasonably well with the
experimental data. The polarization properties of the Lambda and Sigma^0
hyperons are discussed.

</DOC>
<DOC>
<DOCNO> 84203 </DOCNO>
Transition from inspiral to plunge in binary black hole coalescences


  Combining recent techniques giving non-perturbative re-summed estimates of
the damping and conservative parts of the two-body dynamics, we describe the
transition between the adiabatic phase and the plunge, in coalescing binary
black holes with comparable masses moving on quasi-circular orbits. We give
initial dynamical data for numerical relativity investigations, with a fraction
of an orbit left, and provide, for data analysis purposes, an estimate of the
gravitational wave-form emitted throughout the inspiral, plunge and coalescence
phases.

</DOC>
<DOC>
<DOCNO> 69304 </DOCNO>
The Reach of LHC (CMS) for Models with Effective Supersymmetry and


  We investigate squark and gluino pair production at LHC (CMS) with subsequent
decays into quarks, leptons and LSP in models with effective supersymmetry
where third generation of squarks is relatively light while the first two
generations of squarks are heavy. We consider the general case of nonuniversal
gaugino masses. Visibility of signal by an excess over SM background in $(n
\geq 2)jets + (m \geq 0)leptons + E^{miss}_T$ events depends rather strongly on
the relation between LSP, second neutralino, gluino and squark masses and it
decreases with the increase of LSP mass.

</DOC>
<DOC>
<DOCNO> 68192 </DOCNO>
Theory of Light Hydrogenlike Atoms


  The present status and recent developments in the theory of light hydrogenic
atoms, electronic and muonic, are extensively reviewed. The discussion is based
on the quantum field theoretical approach to loosely bound composite systems.
The basics of the quantum field theoretical approach, which provide the
framework needed for a systematic derivation of all higher order corrections to
the energy levels, are briefly discussed. The main physical ideas behind the
derivation of all binding, recoil, radiative, radiative-recoil, and
nonelectromagnetic spin-dependent and spin-independent corrections to energy
levels of hydrogenic atoms are discussed and, wherever possible, the
fundamental elements of the derivations of these corrections are provided. The
emphasis is on new theoretical results which were not available in earlier
reviews. An up-to-date set of all theoretical contributions to the energy
levels is contained in the paper. The status of modern theory is tested by
comparing the theoretical results for the energy levels with the most precise
experimental results for the Lamb shifts and gross structure intervals in
hydrogen, deuterium, and helium ion $He^+$, and with the experimental data on
the hyperfine splitting in muonium, hydrogen and deuterium.

</DOC>
<DOC>
<DOCNO> 116292 </DOCNO>
Using atomic interference to probe atom-surface interaction


  We show that atomic interference in the reflection from two suitably
polarized evanescent waves is sensitive to retardation effects in the
atom-surface interaction for specific experimental parameters. We study the
limit of short and long atomic de Broglie wavelength. The former case is
analyzed in the semiclassical approximation (Landau-Zener model). The latter
represents a quantum regime and is analyzed by solving numerically the
associated coupled Schroedinger equations. We consider a specific experimental
scheme and show the results for rubidium (short wavelength) and the much
lighter meta-stable helium atom (long wavelength). The merits of each case are
then discussed.

</DOC>
<DOC>
<DOCNO> 170128 </DOCNO>
Low-energy relativistic effects and nonlocality in time-dependent


  We consider exact time-dependent analytic solutions to the Schr\"odinger
equation for tunneling in one dimension with cut off wave initial conditions at
$t=0$. We obtain that as soon as $t \neq 0$ the transmitted probability density
at any arbitrary distance rises instantaneously with time in a linear manner.
Using a simple model we find that the above nonlocal effect of the
time-dependent solution is suppressed by consideration of low-energy
relativistic effects. Hence at a distance $x_0$ from the potential the
probability density rises after a time $t_0=x_0/c$ restoring Einstein
causality. This implies that the tunneling time of a particle can never be
zero.

</DOC>
<DOC>
<DOCNO> 118232 </DOCNO>
Morphology and kinematics of Planetary Nebulae II. A Diabolo model for


  We use a 3D photoionization modeling tool to study the morpho-kinematic
properties of the Planetary Nebula (PN) NGC 3132. We show that it is possible
to reproduce the low resolution observations (spectra and images) with an
ellipsoidal shell. However, high resolution observations, as those showing a
density variation along the nebula and the [O III]5007 velocity profiles,
definitively rule out this description. We show that a bipolar Diabolo shape
with a 40 degres rotation of the symmetry axis relative to the line of sight
successfully reproduces the observed images, as well as the high resolution
observations.

</DOC>
<DOC>
<DOCNO> 85272 </DOCNO>
When is S=A/4?


  In this note we consider black hole entropy and its relation to the horizon
area. More precisely, we discuss the conditions and specifications that are
expected to be required for the assignment of entropy to a physical situation.
We explore the consequences that these expectations would have when applied to
the case of a black hole. We conclude that our present understanding of the
matter is rather incomplete, and we point out some of the relevant issues that
should be addressed in pursuing these questions.

</DOC>
<DOC>
<DOCNO> 10193 </DOCNO>
Local lattice disorder in the geometrically-frustrated spin glass


  The geometrically-frustrated spin glass Y2Mo2O7 has been considered widely to
be crystallographically ordered with a unique nearest neighbor magnetic
exchange interaction, J. To test this assertion, we present x-ray-absorption
fine-structure results for the Mo and Y K edges as a function of temperature
and compare them to results from a well-ordered pyrochlore, Tl2Mn2O7. We find
that the Mo-Mo pair distances are significantly disordered at approximately
right angles to the Y-Mo pairs. These results strongly suggest that lattice
disorder nucleates the spin-glass phase in this material.

</DOC>
<DOC>
<DOCNO> 118384 </DOCNO>
The Mystery of Ultra-High Energy Cosmic Rays


  The origin of cosmic rays with energies higher than 10$^{20}$ eV remains a
mystery. Accelerating particles up to these energies is a challenge even for
the most energetic astrophysical objects known. While the isotropy in arrival
directions argues for an extra-galactic origin, the photon-pion production off
the cosmic background radiation limits the sources of such particles to systems
less than 50 Mpc away from us. The combination of large gyroradii, efficient
energy losses, and isotropic arrival directions defies most of the proposed
astrophysical accelerators as well as the more exotic alternatives. I briefly
review theoretical models for the acceleration and propagation of
ultra-high-energy cosmic-rays and discuss the potential for future
observatories to resolve this cosmic mystery.

</DOC>
<DOC>
<DOCNO> 68648 </DOCNO>
Flow Equations for Gluodynamics in the Coulomb Gauge


  A systematic procedure to consistently formulate a field theoretical, QCD
bound state problem with a fixed number of constituents is outlined. The
approach entails applying the Hamiltonian flow equations, which are a set of
continuous unitary transformations, to a QCD motivated Hamiltonian with a
confining interaction. The method is developed in detail for gluodynamics in
the Coulomb gauge to obtain an effective block-diagonal Hamiltonian appropriate
to a reduced Fock space with fixed number of dynamical gluons. Standard
many-body techniques are used to numerically diagonalize this Hamiltonian in a
constituent two gluon Fock space. The calculated gluon condensates and glueball
masses are in good agreement with QCD sum rule and lattice results.

</DOC>
<DOC>
<DOCNO> 101873 </DOCNO>
Detecting flat normal cones using Segre classes


  Given a flat, projective morphism $Y \to T$ from an equidimensional scheme to
a nonsingular curve and a subscheme $Z$ of $Y$, we give conditions under which
specialization of the Segre class $s(N_{Z}Y)$ of the normal cone of $Z$ in $Y$
implies flatness of the normal cone. We apply this result to study when the
relative tangent star cone of a flat family is flat.

</DOC>
<DOC>
<DOCNO> 9475 </DOCNO>
Phase-ordering and persistence: relative effects of


  The peculiar phase-ordering properties of a lattice of coupled chaotic maps
studied recently (A. Lema\^\i tre & H. Chat\'e, {\em Phys. Rev. Lett.} {\bf
82}, 1140 (1999)) are revisited with the help of detailed investigations of
interface motion. It is shown that ``normal'', curvature-driven-like domain
growth is recovered at larger scales than considered before, and that the
persistence exponent seems to be universal. Using generalized persistence
spectra, the properties of interface motion in this deterministic, chaotic,
lattice system are found to ``interpolate'' between those of the two canonical
reference systems, the (probabilistic) Ising model, and the (deterministic),
space-continuous, time-dependent Ginzburg-Landau equation.

</DOC>
<DOC>
<DOCNO> 69260 </DOCNO>
Non equilibrium spectra of degenerate relic neutrinos


  We calculate the exact kinetic evolution of cosmic neutrinos until complete
decoupling, in the case when a large neutrino asymmetry exists. While not
excluded by present observations, this large asymmetry can have relevant
cosmological consequences and in particular may be helpful in reconciling
Primordial Nucleosynthesis with a high baryon density as suggested by the most
recent observations of the Cosmic Microwave Background Radiation. By solving
numerically the Boltzmann kinetic equations for the neutrino distribution
functions, we find the momentum-dependent corrections to the equilibrium
spectra and briefly discuss their phenomenological implications.

</DOC>
<DOC>
<DOCNO> 68969 </DOCNO>
Neutrino Masses and Mixings from Supersymmetry with Bilinear R--Parity


  The simplest unified extension of the MSSM with bi-linear R--Parity violation
naturally predicts a hierarchical neutrino mass spectrum, in which one neutrino
acquires mass by mixing with neutralinos, while the other two get mass
radiatively. We have performed a full one-loop calculation of the
neutralino-neutrino mass matrix in the bi-linear \rp MSSM, taking special care
to achieve a manifestly gauge invariant calculation. Moreover we have performed
the renormalization of the heaviest neutrino, needed in order to get meaningful
results. The atmospheric mass scale and maximal mixing angle arise from
tree-level physics, while solar neutrino scale and oscillations follow from
calculable one-loop corrections. If universal supergravity assumptions are made
on the soft-supersymmetry breaking terms then the atmospheric scale is
calculable as a function of a single \rp violating parameter by the
renormalization group evolution due to the non-zero bottom quark Yukawa
coupling. The solar neutrino problem must be accounted for by the small mixing
angle (SMA) MSW solution. If these assumptions are relaxed then one can
implement large mixing angle solutions, either MSW or just-so. The theory
predicts the lightest supersymmetic particle (LSP) decay to be observable at
high-energy colliders, despite the smallness of neutrino masses indicated by
experiment. This provides an independent way to test this solution of the
atmospheric and solar neutrino anomalies.

</DOC>
<DOC>
<DOCNO> 117859 </DOCNO>
Feedback Processes in the Early Universe


  Feedback effects due to massive stars and supernovae in the first objects are
shown to strongly regulate both galaxy formation/evolution and the reionization
process. Here we review the most important ones in some detail. We discuss how
Type II supernovae can be used as tracers of the first objects and detected
with NGST, for which we predict supernova number counts including the effects
of gravitational lensing. Preliminary results on the formation of dust in the
ejecta of supernovae of primordial composition are also presented. We finally
turn to the consideration of the process of inhomogeneous reionization due to
primordial stellar sources by means of high resolution numerical simulations,
allowing for a self-consistent treatment of the above feedback processes. These
simulations allow us to draw conclusions on the evolution and epoch of
reionization and about the fate of reionizing objects. We conclude that a large
fraction (~ 99%) of collapsed objects must be dark at redshift around eight.

</DOC>
<DOC>
<DOCNO> 117713 </DOCNO>
Chandra X-ray Observations of the Hydra A Cluster: An Interaction


  We present Chandra X-ray Observations of the Hydra A cluster of galaxies, and
we report the discovery of structure in the central 80 kpc of the cluster's
X-ray-emitting gas. The most remarkable structures are depressions in the X-ray
surface brightness, $\sim 25-35$ kpc diameter, that are coincident with Hydra
A's radio lobes. The depressions are nearly devoid of X-ray-emitting gas, and
there is no evidence for shock-heated gas surrounding the radio lobes. We
suggest the gas within the surface brightness depressions was displaced as the
radio lobes expanded subsonically, leaving cavities in the hot atmosphere. The
gas temperature declines from 4 keV at 70 kpc to 3 keV in the inner 20 kpc of
the brightest cluster galaxy (BCG), and the cooling time of the gas is $\sim
600$ Myr in the inner 10 kpc. These properties are consistent with the presence
of a $\sim 34 \msunyr$ cooling flow within a 70 kpc radius. Bright X-ray
emission is present in the BCG surrounding a recently-accreted disk of nebular
emission and young stars. The star formation rate is commensurate with the
cooling rate of the hot gas within the volume of the disk, although the sink
for the material cooling at larger radii remains elusive.

</DOC>
<DOC>
<DOCNO> 84419 </DOCNO>
New approach to the evolution of neutron star oscillations


  We present a new derivation of the perturbation equations governing the
oscillations of relativistic non-rotating neutron star models using the
ADM-formalism. This formulation has the advantage that it immediately yields
the evolution equations in a hyperbolic form, which is not the case for the
Einstein field equations in their original form. We show that the perturbation
equations can always be written in terms of spacetime variables only,
regardless of any particular gauge. We demonstrate how to obtain the
Regge-Wheeler gauge, by choosing appropriate lapse and shift. In addition, not
only the 3-metric but also the extrinsic curvature of the initial slice have to
satisfy certain conditions in order to preserve the Regge-Wheeler gauge
throughout the evolution. We discuss various forms of the equations and show
their relation to the formulation of Allen et al. New results are presented for
polytropic equations of state. An interesting phenomenon occurs in very compact
stars, where the first ring-down phase in the wave signal corresponds to the
first quasinormal mode of an equal mass black hole, rather than to one of the
proper quasinormal modes of the stellar model. A somewhat heuristic explanation
to account for this phenomenon is given. For realistic equations of state, the
numerical evolutions exhibit an instability, which does not occur for
polytropic equations of state. We show that this instability is related to the
behavior of the sound speed at the neutron drip point. As a remedy, we devise a
transformation of the radial coordinate $r$ inside the star, which removes this
instability and yields stable evolutions for any chosen numerical resolution.

</DOC>
<DOC>
<DOCNO> 9814 </DOCNO>
Considerations about universality in phase-ordering of binary liquids


  In this article we show that the phase-ordering scaling state for binary
fluids is not necessarily unique and that local correlations in the initial
conditions can be responsible for selecting the scaling state. We describe a
new scaling state for symmetric volume fractions that consists of drops of the
one component suspended in a matrix of the other. The underlying reason for the
existence of the newly observed scaling state is that the main coarsening
mechanism of binary fluids which is the deformation of interfaces by flow is
not acting, and this leads to a new scaling law. An initial droplet state can
be formed by a number of physical phenomena. In a unified description this can
be undestood as local correlations in the initial conditions. Local
correlations with length $\xi$ are believed to be irrelevant when the typical
length scale L of the system is large ($L\gg \xi$). Our result shows that these
initial correlations, contrary to current thinking, can be important even at
late times.

</DOC>
<DOC>
<DOCNO> 84736 </DOCNO>
Tracking Extended Quintessence


  We study the cosmological role of a Tracking Field $\phi$ in Extended
Quintessence scenarios (TEQ), where the dynamical vacuum energy driving the
acceleration of the universe today is coupled with the Ricci scalar, $R$, with
a term of the form $F(\phi)R/2$, where $F(\phi) = 1/8\pi
G+\xi(\phi^{2}-\phi_{0}^{2})$. Tracker solutions for these NMC models, with
inverse power-law potentials, possess an initial enhancement of the scalar
field dynamics, named $R$-boost, caused by the Ricci scalar in the Klein-Gordon
equation. During this phase the field performs a "gravitational" slow rolling
which we model analytically, with energy density scaling as $(1+z)^{2}$. We
evolve linear perturbations in TEQ models assuming Gaussian scale-invariant
initial spectrum. We obtain significant changes in the Integrated Sachs Wolfe
effect and in the acoustic peaks locations on the Cosmic Microwave Background,
as well as in the turnover on the matter power spectrum. All these corrections
may assume positive as well as negative values, depending on the sign of the
NMC parameter $\xi$. We give analytical formulas describing all these effects.
We show that they can be as large as $10 - 30%$ with respect to equivalent
cosmological constant and ordinary tracking Quintessence models, respecting all
the existing experimental constraints on scalar-tensor theories of gravity.
These results demonstrate that the next decade data will provide deep
constraints on the nature of the dark energy in the Universe, as well as the
structure of the theory of gravity.

</DOC>
<DOC>
<DOCNO> 118992 </DOCNO>
On the supernovae heating of intergalactic medium


  We present estimates of the energy input from supernovae (SNe) into the
intergalactic medium using (i) recent measurements of Si and Fe abundances in
the intracluster medium (ICM) and (ii) self-consistent gasdynamical galaxy
formation simulations that include processes of cooling, star formation, SNe
feedback, and a multi-phase model of the interstellar medium. We estimate the
energy input from observed abundances using two different assumptions: (i)
spatial uniformity of metal abundances in the ICM and (ii) radial abundance
gradients. We show that these two cases lead to energy input estimates which
are different by an order of magnitude, highlighting a need for observational
data on large-scale abundance gradients in clusters. Analysis of galaxy
formation results and estimates from observed Fe and Si abundances indicates
that the SNe energy input can be important for heating of the entire ICM
(providing energy of ~1 keV per particle) only if the ICM abundances are
uniform and the efficiency of gas heating by SN explosions is close to 100%
(implying that all of the initial kinetic energy of the explosion goes into
heating of the ICM). We conclude that unless these most favorable conditions
are met, SNe alone are unlikely to provide sufficient energy input to heat all
of the cluster ICM and may need to be supplemented or even substituted by some
other heating process(es). (Abridged)

</DOC>
<DOC>
<DOCNO> 85635 </DOCNO>
Generalized geometries and kinematics for Quantum Gravity


  Our proposal here is to set up the conceptual framework for an eventual
{Theory of Everything}.
  We formulate the arena -language- to build up {\it any} QG. In particular, we
show how the objects of fundamental theories, such as p-branes (strings, loops
and others) could be posed in this language.

</DOC>
<DOC>
<DOCNO> 116873 </DOCNO>
Linac Lue200. First Testing Results


  "LUE200" - 200 MeV electron linac is being created at JINR as a driver of the
pulsed neutron source "IREN" [1]. The special full-scale facilities for testing
the main systems of LUE-200 (FSTF) are used at JINR, BINP, MEPhI and YerPhI
[2]. The verification of the linac accelerating system is providing at the
VEPP-5 preinjector constructed at BINP [3]. The accelerating system of LUE200
includes two S-band (2856 MHz) accelerating sections of 3 m long. The sections
are connected with modulator based one 5045 klystron (SLAC production). There
are SLED-systems for the multiplying the pulse RF power. The first results of
the accelerating system test on the VEPP-5 preinjector are presented. The
electron beam energy up to 92 MeV and consequently average rate of acceleration
of the electron beam more than 30 MeV/m were achieved after acceleration in one
section.

</DOC>
<DOC>
<DOCNO> 152187 </DOCNO>
Gravitational dressing of D-instantons


  The non-perturbative corrections to the universal hypermultiplet moduli space
metric in the type-IIA superstring compactification on a Calabi-Yau threefold
are investigated in the presence of 4d, N=2 supergravity. These corrections
come from multiple wrapping of the BPS (Euclidean) D2-branes around certain
(BPS) Calabi-Yau 3-cycles, and they are known as the D-instantons. The exact
universal hypermultiplet metric is governed by a quaternionic potential that
satisfies the SU(\infty) Toda equation. The mechanism is proposed, which
elevates any four-dimensional hyper-K"ahler metric with a rotational isometry
to the quaternionic metric of the same dimension. A generic separable solution
to the Toda equation appears to be related to the Eguchi-Hanson metric, whereas
another solution originating from the Atiyah-Hitchin metric describes the
gravitationally dressed (mixed) D-instantons.

</DOC>
<DOC>
<DOCNO> 69764 </DOCNO>
Radion stabilization in the Randall-Sundrum model with qudratic and


  In this report we investigate the Goldberger-Wise (GW) mechanism of radion
stabilization with quartic potential on the hidden brane and quadratic
potential on the visible brane. The advantage of our simplified scenario over
the original GW mechanism is that the modulus potential can be evaluated for
finite $\lv$ and $\lh$. This enables us to probe how the modulus potential
behaves over the entire range of $\lh$. By staying away from the GW limit of
${k \over \lv v_v^2} \to $0 and ${k \over \lh v_h^2}\to $0 we show that it is
possible to choose the parameters of the model so that the potential exhibits a
minimum at $k\rc \approx$ 12 and this adjustment does not involve any extreme
fine tuning of parameters.

</DOC>
<DOC>
<DOCNO> 119231 </DOCNO>
Overabundance of Calcium in the young SNR RX J0852$-$4622: evidence of


  Recently, COMPTEL has detected $\gamma$-rays of 1157 keV from $^{44}$Ti in
the direction of the SNR RX J0852$-$4622 (Iyudin et al. 1998). Since $^{44}$Ti
is a product of explosive nucleosynthesis and its half lifetime $\tau\sb{1/2}$
is about 60 yrs, RX J0852$-$4622 must be a young supernova remnant and
radiation is dominated by the ejecta rather than by interstellar matter. We
have detected an X-ray emission line at $4.1\pm 0.2$ keV which is thought to
come from highly ionized Ca. The emission line is so far only seen in the
north-west shell region of RX J0852$-$4622. The X-ray spectrum can be well
fitted with that of thin hot plasma of cosmic abundances except that of Ca,
which is overabundant by a factor of $8 \pm 5$. Assuming that most of Ca is
$^{44}$Ca, which originates from $^{44}$Ti by radioactive decay, we estimate a
total Ca mass of about $1.1\times 10^{-3}M_\odot$. Combining the amount of
$^{44}$Ca and the observed flux of the $^{44}$Ti $\gamma$-ray line, the age of
RX J0852$-$4622 is around 1000 yrs.

</DOC>
<DOC>
<DOCNO> 40130 </DOCNO>
Testing Lorentz invariance violations in the tritium beta-decay anomaly


  We consider a Lorentz non-invariant dispersion relation for the neutrino,
which would produce unexpected effects with neutrinos of few eV, exactly where
the tritium beta-decay anomaly is found. We use this anomaly to put bounds on
the violation of Lorentz invariance. We discuss other consequences of this
non-invariant dispersion relation in neutrino experiments and high-energy
cosmic-ray physics.

</DOC>
<DOC>
<DOCNO> 170678 </DOCNO>
On 1-qubit channels


  The entropy H_T(rho) of a state rho with respect to a channel T and the
Holevo capacity of the channel require the solution of difficult variational
problems. For a class of 1-qubit channels, which contains all the extremal
ones, the problem can be significantly simplified by associating an Hermitian
antilinear operator theta to every channel of the considered class. The
concurrence of the channel can be expressed by theta and turns out to be a flat
roof. This allows to write down an explicit expression for H_T. Its maximum
would give the Holevo (1-shot) capacity.

</DOC>
<DOC>
<DOCNO> 70346 </DOCNO>
The $\rho$ Spectral Function in a Relativistic Resonance Model


  We calculate the spectral function $A_\rho$ of the $\rho$ meson in nuclear
matter. The calculation is performed in the {\it low density} approximation,
where the in-medium self energy $\Sigma_{med}$ is completely determined by the
vacuum $\rho N$ forward scattering amplitude. This amplitude is derived from a
relativistic resonance model. In comparison to previous non-relativistic
calculations we find a much weaker momentum dependence of $\Sigma_{med}$,
especially in the transverse channel. Special attention is paid to
uncertainties in the model. Thus, we compare the impact of different coupling
schemes for the $RN\rho$ interaction on the results and discuss various
resonance parameter sets.

</DOC>
<DOC>
<DOCNO> 150607 </DOCNO>
Torsionless T-selfdual Affine NA Toda Models


  A general construction of affine Non Abelian Toda models in terms of gauged
two loop WZNW model is discussed. In particular we find the
 Lie algebraic condition defining a subclass of {\it T-selfdual torsionless NA
Toda models} and their zero curvature representation.

</DOC>
<DOC>
<DOCNO> 122324 </DOCNO>
H-alpha Equivalent Width Variations across the Face of a Microlensed K


  We present VLT FORS1 spectroscopy that temporally resolves the second caustic
crossing of the Bulge K giant source of microlensing event EROS 2000-BLG-5, the
first time this has been accomplished for several phases of a caustic transit.
The ~1 angstrom H-alpha equivalent width of the source star increases slightly
as the center of the star egresses the caustic and then plummets by 30% during
the final limb crossing. These changes are not seen in contemporaneous spectra
of control stars in the FORS1 slit, but are qualitatively consistent with
expectations from stellar atmosphere models as the caustic differentially
magnifies different portions of the stellar face of the target. Observations
such as these in a variety of stellar lines are equivalent to atmospheric
tomography and are expected to provide a direct test of stellar models.

</DOC>
<DOC>
<DOCNO> 100524 </DOCNO>
On two simple criteria for recognizing complete intersections in


  Developing a previous idea of Faltings, we characterize the complete
intersections of codimension 2 in P^n, n>=3, over an algebraically closed field
of any characteristic, among l.c.i. X, as those that are subcanonical and
scheme-theoretically defined by p<=n-1 equations. Moreover, we give some other
results assuming that the normal bundle of X extends to a numerically split
bundle on P^n, p<=n and the characteristic of the base field is zero. Finally,
we give a (partial) answer to a question posed recently by Franco, Kleiman and
Lascu on self-linking and complete intersections in positive characteristic.

</DOC>
<DOC>
<DOCNO> 116897 </DOCNO>
Measurement of the six Dimensional Phase Space at the New GSI High


  For the characterization of the 10 mA ion beam delivered by the new High
Current Linac at GSI, sophisticated, mainly non-intersepting diagnostic devices
were developed. Besides the general set-up of a versatile test bench, we
discuss in particular bunch shape and emittance measurements. A direct
time-of-flight technique with a diamond particle detector is used to observe
the micro-bunch distribution with a resolution of $\sim 25 $ ps equals
0.3$^{o}$ in phase. For the determination of the energy spread a coincidence
technique is applied, using secondary electrons emitted by the ion passing
through an aluminum foil 80 cm upstream of the diamond detector. The transverse
emittance is measured within one macro pulse with a pepper-pot system equipped
with a high performance CCD camera.

</DOC>
<DOC>
<DOCNO> 101984 </DOCNO>
Numerology


  One presents many Concatenated and Operation Sequences, P-Q Relationships,
Digital Sequences, Magic Squares, Prime Conjectures, k-Divisibility and Strong
Divisibility Sequences, Geometric Conjectures, Proposed problems.

</DOC>
<DOC>
<DOCNO> 8873 </DOCNO>
Unconventional odd-parity superconductivity in the ladder compounds


  Superconductive properties of the two-leg ladder compounds are studied
theoretically. The antiferromagnetic fluctuations are considered because of the
good nesting of the Fermi surfaces. The attractive interaction which is most
likely due to the electron-phonon coupling is also taken into account. Under
this circumstance, it is shown that the superconductivity has two sets of
spin-triplet pairings. The gaps for both pairings have no node.

</DOC>
<DOC>
<DOCNO> 100803 </DOCNO>
Multiresolution wavelet analysis of Bessel functions of scale $\nu +1$


  We identify multiresolution subspaces giving rise via Hankel transforms to
Bessel functions. They emerge as orthogonal systems derived from geometric
Hilbert-space considerations, the same way the wavelet functions from a
multiresolution scaling wavelet construction arise from a scale of Hilbert
spaces. We study the theory of representations of the C*-algebra O_{\nu+1}
arising from this multiresolution analysis.

</DOC>
<DOC>
<DOCNO> 68230 </DOCNO>
Thermal Equilibration and Ellipsoidal Expansion of


  A rotationally-symmetrical ellipsoidal flow model is proposed for the
relativistic heavy-ion collisions and compared with the 14.6 A GeV/c Si-Al and
10.8 A GeV/c Au-Au collision data. The large stopping in the heavier collision
system and heavier produced particles is accounted for by using the ellipsoidal
flow picture. The central dip in the proton and deuteron rapidity distributions
for Si-Al collision are reproduced.

</DOC>
<DOC>
<DOCNO> 40266 </DOCNO>
Weak and Electromagnetic Nuclear Decay Signatures for Neutrino Reactions


  We suggest the study of events in the SuperKamiokande neutrino data due to
charged- and neutral-current neutrino reactions followed by weak and/or
electromagnetic decays of struck nuclei and fragments thereof. This study could
improve the prospects of obtaining evidence for $\tau$ production from $\nu_\mu
\to \nu_\tau$ oscillations and could augment the data sample used to disfavor
$\nu_\mu \to \nu_{sterile}$ oscillations.

</DOC>
<DOC>
<DOCNO> 84299 </DOCNO>
Is gravity inherent to relativistic many-particle systems?


  This paper discusses the somewhat unintuitive conjecture that many
Lorentz-invariant many-particle models can be reinterpreted to satisfy the gtr
field equations. It is shown that a careful remapping of coordinates yields a
non-trivial Riemannian manifold. Furthermore an energy-momentum tensor is
outlined and it is argued that it may converge to its classical counterpart in
the macroscopic limit. These ideas could possibly be used to partially relieve
us of some the resilient problems of adding spacetime curvature to modern QM
theories.

</DOC>
<DOC>
<DOCNO> 100760 </DOCNO>
Moduli for morphisms of abelian varieties


  The moduli space of morphisms between polarized complex abelian varieties is
described. The discrete invariants, derived from a Poincare' decomposition of
morphisms, are the types of polarizations and of lattice homomorphisms
occurring in the decomposition. They are sufficient in order to detect the
irreducible components for the moduli space of morphisms which are compatible
with the polarizations.

</DOC>
<DOC>
<DOCNO> 118205 </DOCNO>
Fractal structures and the large scale distribution of galaxies


  Galaxy structures are certainly fractal up to a certain crossover scale
\lambda_0. A clear determination of such a scale is still missing. Usually, the
conceptual and practical implications of this property are neglected and the
structures are only discussed in terms of their global amplitude. Here we
present a compact summary of these implications. First, we discuss the problem
of the identification of the crossover scale \lambda_0 and the proper
characterization of the scaling. We then consider the implications of these
properties with respect to various physical phenomena and to the corresponding
characteristic values, i.e. r_0, \sigma_8, \Omega, etc. These implications
crucially depend on the value of \lambda_0, but they are still important for a
relatively small value, say \lambda_0 \approx 50 \hmp. Finally we consider the
main theoretical consequences of these results.

</DOC>
<DOC>
<DOCNO> 11142 </DOCNO>
Interface fluctuations, bulk fluctuations and dimensionality in the


  The relationship between statics and dynamics proposed by Franz, Mezard,
Parisi and Peliti (FMPP) for slowly relaxing systems [Phys.Rev.Lett. {\bf 81},
1758 (1998)] is investigated in the framework of non disordered coarsening
systems. Separating the bulk from interface response we find that for statics
to be retrievable from dynamics the interface contribution must be
asymptotically negligible. How fast this happens depends on dimensionality.
There exists a critical dimensionality above which the interface response
vanishes like the interface density and below which it vanishes more slowly. At
$d=1$ the interface response does not vanish leading to the violation of the
FMPP scheme. This behavior is explained in terms of the competition between
curvature driven and field driven interface motion.

</DOC>
<DOC>
<DOCNO> 13636 </DOCNO>
Incommensurate structure factor in a hole-doped spin-1 system


  The nickelate compound Y_{2}BaNiO_{5} is a spin-1 Haldane-gap
antiferromagnet. The compound is doped with holes on replacing the off-chain
Y^{3+} ions by Ca^{2+} ions. Inelastic neutron scattering (INS) experiments
reveal the existence of sub-gap states on doping. A recent INS experiment
provides evidence for an incommensurate double-peaked structure factor S(q)
corresponding to the sub-gap states. In this paper, we formulate a microscopic
theory for the origin of the incommensurate peak.

</DOC>
<DOC>
<DOCNO> 13071 </DOCNO>
Moving averages and markets inefficiency


  We introduce a stochastic price model where, together with a random
component, a moving average of logarithmic prices contributes to the price
formation. Our model is tested against financial datasets, showing an extremely
good agreement with them. It suggests how to construct trading strategies which
imply a capital growth rate larger than the growth rate of the underlying
asset, with also the effect of reducing the fluctuations. These results are a
clear evidence that some hidden information is not fully integrated in price
dynamics, and therefore financial markets are partially inefficient. In simple
terms, we give a recipe for speculators to make money as long as only few
investors follow it.

</DOC>
<DOC>
<DOCNO> 100073 </DOCNO>
On the zero modes of Pauli operators


  Two results are proved for $\mathrm{nul} \mathbb{P}_A$, the dimension of the
kernel of the Pauli operator $\mathbb{P}_A = \bigl\{\bbf{\sigma} \cdotp
\bigl(\frac{1}{i} \bbf{\nabla} + \vec{A} \bigr) \bigr\} ^2 $ in $[L^2
(\mathbb{R}^3)]^2$: (i) for $|\vec{B}| \in L^{3/2} (\mathbb{R}^3),$ where
$\vec{B} = \mathrm{curl} \vec{A}$ is the magnetic field, $\mathrm{nul} \
\mathbb{P}_{tA} = 0$ except for a finite number of values of $t$ in any compact
subset of $(0, \infty)$; (ii) $\bigl\{\vec{B}: \mathrm{nul} \mathbb{P}_{A} = 0,
| \vec{B} | \in L^{3/2}(\mathbb{R}^3) \bigr\} $ contains an open dense subset
of $[L^{3/2}(\mathbb{R}^3)]^3$.

</DOC>
<DOC>
<DOCNO> 99860 </DOCNO>
Genus one 1-bridge knots and Dunwoody manifolds


  In this paper we show that all 3-manifolds of a family introduced by M. J.
Dunwoody are cyclic coverings of lens spaces (eventually $\bf S^3$), branched
over genus one 1-bridge knots. As a consequence, we give a positive answer to
the Dunwoody conjecture that all the elements of a wide subclass are cyclic
coverings of $\bf S^3$ branched over a knot. Moreover, we show that all
branched cyclic coverings of a 2-bridge knot belong to this subclass; this
implies that the fundamental group of each branched cyclic covering of a
2-bridge knot admits a geometric cyclic presentation.

</DOC>
<DOC>
<DOCNO> 9042 </DOCNO>
Importance of Coupling between the Charge and Spin Degrees of Freedom in


  Based on an improved SU(2) slave-boson approach showing coupling between the
cha rge and spin degrees of freedom, we derive a phase diagram of high $T_c$
cuprate s which displays both the superconducting and pseudogap phases in the
plane of t emperature vs. hole doping rate. It is shown that phase fluctuations
in the order parameters results in a closer agreement with the observed phase
diagram of an arch shape, by manifesting the p resence of an optimal doping
rate.

</DOC>
<DOC>
<DOCNO> 9882 </DOCNO>
Universality and nonmonotonic finite-size effects above the upper


  We analyze universal and nonuniversal finite-size effects of lattice systems
in a $L^d$ geometry above the upper critical dimension d = 4 within the O(n)
symmetric $\phi^4$ lattice theory. On the basis of exact results for $n
\to\infty$ and one-loop results for n = 1 we identify significant lattice
effects that cannot be explained by the $\phi^4$ continuum theory. Our analysis
resolves longstanding discrepancies between earlier asymptotic theories and
Monte Carlo (MC) data for the five-dimensional Ising model of small size. We
predict a {\it nonmonotonic} L dependence of the scaled susceptibility $\chi
L^{-d/2}$ at $T_c$ with a weak maximum that has not yet been detected by MC
data.

</DOC>
<DOC>
<DOCNO> 80628 </DOCNO>
Vortices in SO(3)xZ(2) simulations


  We study the configuration space of the Tomboulis $SO(3) \times Z(2)$
formulation with periodic boundary conditions. The dynamical variables are
constrained by the required coincidence of Z(2) and SO(3) monopoles. We propose
an update algorithm that satisfies the constraints and is straightforward to
implement. We further prove that this it reaches all configurations. We show
how the boundary conditions put constraints on the configuration space.
  We measure gauge invariant vortex counters for "thin",
  "thick" and "hybrid" vortex sheets. For comparison we also measure projection
vortex counters defined in the maximal center gauge.

</DOC>
<DOC>
<DOCNO> 151470 </DOCNO>
Integral representations for the eigenfunctions of quantum open and


  The integral representations for the eigenfunctions of $N$ particle quantum
open and periodic Toda chains are constructed in the framework of Quantum
Inverse Scattering Method (QISM). Both periodic and open $N$-particle solutions
have essentially the same structure being written as a generalized Fourier
transform over the eigenfunctions of the $N-1$ particle open Toda chain with
the kernels satisfying to the Baxter equations of the second and first order
respectively. In the latter case this leads to recurrent relations which result
to representation of the Mellin-Barnes type for solutions of an open chain. As
byproduct, we obtain the Gindikin-Karpelevich formula for the Harish-Chandra
function in the case of $GL(N,\RR)$ group.

</DOC>
<DOC>
<DOCNO> 40027 </DOCNO>
New Method for Data Treating in Polarization Measurements


  Precise formulas are derived for the expected values $<\xi>$, $<\eta>$ and
variances $\delta \xi ^2$, $\delta \eta ^2$ of random variables $\xi$, $\eta$
describing the spin asymmetry of some reaction when a background process
contribution is negligible and appreciable, respectively. The variances of
$\xi$ and $\eta$ are proved to be finite. This property differs from that of
the Caushy distribution which has an infinite variance. It is shown that
$<\xi>$ is equal to the physical asymmetry which allows to find the asymmetry
from experimental data without studying the detector efficiency. This is the
base of the proposed method of data treating. Asymptotic formulas for $<\eta>$
and $\delta \eta ^2$ are also derived for a total number of events tending to
infinity for a finite value of the background to signal ratio.

</DOC>
<DOC>
<DOCNO> 120149 </DOCNO>
Physical Conditions and Spatial Structure in the Molecular Interstellar


  In this review, I discuss recent detailed studies of individual molecular
clouds in M33 in higher rotational transitions of CO, 13CO, and the fine
structure line of atomic carbon. These data reveal that the temperature and
density of the molecular gas is correlated with the presence of nearby massive
star formation, with clouds with more intense star formation having higher
temperatures and lower densities. This effect is most likely due to post-star
formation processing of the molecular gas. A comparison of 13CO observations
for M33 and individual molecular clouds in the Milky Way suggests that a
significant fraction of the molecular interstellar medium resides in low column
density regions and accounts for 30-60% of the CO luminosity. Finally, a
detailed map of a single molecular cloud in the giant HII region NGC 604
reveals an offset between the atomic carbon and CO emission, which indicates
that the dominant source of atomic carbon in this cloud is likely
photodissociation of CO by ultraviolet photons from the massive stars. A
complete map of the CO emission in M33 would be extremely helpful to guide
further detailed studies.

</DOC>
<DOC>
<DOCNO> 122286 </DOCNO>
Optical and Infrared Spectroscopy of the type IIn SN 1998S : Days 3-127


  We present contemporary infrared and optical spectroscopic observations of
the type IIn SN 1998S for the period between 3 and 127 days after discovery. In
the first week the spectra are characterised by prominent broad emission lines
with narrow peaks superimposed on a very blue continuum(T~24000K). In the
following two weeks broad, blueshifted absorption components appeared in the
spectra and the temperature dropped. By day 44, broad emission components in H
and He reappeared in the spectra. These persisted to 100-130d, becoming
increasingly asymmetric. We agree with Leonard et al. (2000) that the broad
emission lines indicate interaction between the ejecta and circumstellar
material (CSM) and deduce that progenitor of SN 1998S appears to have gone
through at least two phases of mass loss, giving rise to two CSM zones.
Examination of the spectra indicates that the inner zone extended to <90AU,
while the outer CSM extended from 185AU to over 1800AU. Analysis of high
resolution spectra shows that the outer CSM had a velocity of 40-50 km/s.
Assuming a constant velocity, we can infer that the outer CSM wind commenced
more than 170 years ago, and ceased about 20 years ago, while the inner CSM
wind may have commenced less than 9 years ago. During the era of the outer CSM
wind the outflow was high, >2x10^{-5}M_{\odot}/yr corresponding to a mass loss
of at least 0.003M_{\odot} and suggesting a massive progenitor. We also model
the CO emission observed in SN 1998S. We deduce a CO mass of ~10^{-3} M_{\odot}
moving at ~2200km/s, and infer a mixed metal/He core of ~4M_{\odot}, again
indicating a massive progenitor.

</DOC>
<DOC>
<DOCNO> 7728 </DOCNO>
Fine Structure in Magnetization of Individual Fluxoid States


  Each time a vortex enters or exits a small superconductor, a different
fluxoid state develops. We have observed splitting and sharp kinks on
magnetization curves of such individual states. The features are the
manifestation of first and second order transitions, respectively, and reveal
the existence of distinct vortex phases within a superconducting state with a
fixed number of fluxoids. We show that the kinks indicate the merger of
individual vortices into a single giant vortex while the splitting is
attributed to transitions between different arrays of the same number of
vortices.

</DOC>
<DOC>
<DOCNO> 151339 </DOCNO>
CFT, BCFT, ADE and all that


  These pedagogical lectures present some material, classical or more recent,
on (Rational) Conformal Field Theories and their general setting ``in the
bulk'' or in the presence of a boundary. Two well posed problems are the
classification of modular invariant partition functions and the determination
of boundary conditions consistent with conformal invariance. It is shown why
the two problems are intimately connected and how graphs -ADE Dynkin diagrams
and their generalizations- appear in a natural way.

</DOC>
<DOC>
<DOCNO> 100514 </DOCNO>
The gerbe of Higgs bundles


  The purpose of this work is to describe the (category of) Higgs bundles on a
complex scheme X having a given cameral cover X~. We show that this category is
a T_{X~}-gerbe, where T_{X~} is a certain sheaf of abelian groups on X, and we
describe the class of this gerbe precisely. In particular, it follows that the
set of isomorphism classes of Higgs bundles with a fixed cameral cover X~ is a
torsor over the group H^1(X, T_{X~}), which itself parametrizes T_{X~}-torsors
on X. This underlying group can be described as a generalized Prym variety,
whose connected component is either an abelian variety or a degeneration
thereof.

</DOC>
<DOC>
<DOCNO> 70319 </DOCNO>
Capture rate and neutron helicity asymmetry for ordinary muon capture on


  Applying heavy-baryon chiral perturbation theory to ordinary muon capture
(OMC) on a proton, we calculate the capture rate and neutron helicity asymmetry
up to next-to-next-to-leading order. For the singlet hyperfine state, we obtain
the capture rate Gamma_0 = 695 sec^{-1} while, for the triplet hyperfine state,
we obtain the capture rate Gamma_1 = 11.9 sec^{-1} and the neutron asymmetry
alpha_1 = 0.93. If the existing formalism is used to relate these atomic
capture rates to Gamma_{liq}, the OMC rate in liquid hydrogen, then Gamma_{liq}
corresponding to our improved values of Gamma_0 and Gamma_1 is found to be
significantly larger than the experimental value, primarily due to the updated
larger value of g_A. We argue that this apparent difficulity may be correlated
to the specious anomaly recently reported for mu^- + p to n + nu_mu + gamma,
and we suggest a possibility to remove these two "problems" simply and
simultaneously by reexamining the molecular physics input that underlies the
conventional analysis of Gamma_{liq}.

</DOC>
<DOC>
<DOCNO> 83119 </DOCNO>
Logic Programming for Describing and Solving Planning Problems


  A logic programming paradigm which expresses solutions to problems as stable
models has recently been promoted as a declarative approach to solving various
combinatorial and search problems, including planning problems. In this
paradigm, all program rules are considered as constraints and solutions are
stable models of the rule set. This is a rather radical departure from the
standard paradigm of logic programming. In this paper we revisit abductive
logic programming and argue that it allows a programming style which is as
declarative as programming based on stable models. However, within abductive
logic programming, one has two kinds of rules. On the one hand predicate
definitions (which may depend on the abducibles) which are nothing else than
standard logic programs (with their non-monotonic semantics when containing
with negation); on the other hand rules which constrain the models for the
abducibles. In this sense abductive logic programming is a smooth extension of
the standard paradigm of logic programming, not a radical departure.

</DOC>
<DOC>
<DOCNO> 68030 </DOCNO>
Application of heavy-quark effective theory to lattice QCD: I. Power


  Heavy-quark effective theory (HQET) is applied to lattice QCD with Wilson
fermions at fixed lattice spacing a. This description is possible because
heavy-quark symmetries are respected. It is desirable because the ultraviolet
cutoff $1/a$ in current numerical work and the heavy-quark mass $m_Q$ are
comparable. Effects of both short distances, a and $1/m_Q$, are captured fully
into coefficient functions, which multiply the operators of the usual HQET.
Standard tools of HQET are used to develop heavy-quark expansions of lattice
observables and, thus, to propagate heavy-quark discretization errors. Three
explicit examples are given: namely, the mass, decay constant, and semileptonic
form factors of heavy-light mesons.

</DOC>
<DOC>
<DOCNO> 9666 </DOCNO>
Hydration interactions: aqueous solvent effects in electric double


  A model for ionic solutions with an attractive short-range pair interaction
between the ions is presented. The short-range interaction is accounted for by
adding a quadratic non-local term to the Poisson-Boltzmann free energy. The
model is used to study solvent effects in a planar electric double layer. The
counter-ion density is found to increase near the charged surface, as compared
with the Poisson-Boltzmann theory, and to decrease at larger distances. The ion
density profile is studied analytically in the case where the ion distribution
near the plate is dominated only by counter-ions. Further away from the plate
the density distribution can be described using a Poisson-Boltzmann theory with
an effective surface charge that is smaller than the actual one.

</DOC>
<DOC>
<DOCNO> 119175 </DOCNO>
Testing Comptonizing coronae on a long BeppoSAX observation of the


  We test accurate models of Comptonization spectra over the high quality data
of the BeppoSAX long look at NGC 5548, allowing for different geometries of the
scattering region, different temperatures of the input soft photon field and
different viewing angles. We find that the BeppoSAX data are well represented
by a plane parallel or hemispherical corona viewed at an inclination angle of
30$^{\circ}$. For both geometries the best fit temperature of the soft photons
is close to 15$^{+3}_{-9}$ eV. The corresponding best fit values of the hot
plasma temperature and optical depth are $kT_{\rm e}\simeq$ 250--260 keV and
$\tau\simeq$ 0.16--0.37 for the slab and hemisphere respectively. These values
are substantially different from those derived fitting the data with a
power-law + cut off approximation to the Comptonization component ($kT_{\rm
e}\lta$ 60 keV, $\tau\simeq$ 2.4). This is due to the fact that accurate
Comptonization spectra in anisotropic geometries show "intrinsic" curvature
which reduces the necessity of a high energy cut-off. The Comptonization
parameter derived for the slab model {is} larger than predicted for a two phase
plane parallel corona in energy balance, suggesting that a more
``photon-starved'' geometry is necessary. The spectral softening detected
during a flare which occurred in the central part of the observation
corresponds to a decrease of the Comptonization parameter, probably associated
with an increase of the soft photon luminosity, the {hard} photon luminosity
remaining constant.

</DOC>
<DOC>
<DOCNO> 69885 </DOCNO>
Signature of Randall-Sundrum Quantum Gravity model in $\gamma\gamma$


  We examine the implications of the Randall-Sundrum gravity models on
$\gamma\gamma$ scattering in the TeV range.

</DOC>
<DOC>
<DOCNO> 84253 </DOCNO>
Small-eccentricity binary pulsars and relativistic gravity


  Small-eccentricity binary pulsars with white dwarf companions provide
excellent test laboratories for various effects predicted by alternative
theories of gravity, in particular tests for the emission of gravitational
dipole radiation and the existence of gravitational Stark effects. We will
present new limits to these effects. The statistical analysis presented here,
for the first time, takes appropriately care of selection effects.

</DOC>
<DOC>
<DOCNO> 152389 </DOCNO>
Time Evolution as a Gauge Transformation: x^5-dependent Cosmological


  We discuss a new feature of the 5d Kaluza-Klein cosmology. For that purpose,
we obtain the simplest x^5-dependent solution which, in the reduced
description, is associated with a radiation-dominated Robertson-Walker
universe, and also can be regarded as an extension of the Schwarzschild
solution. This solution enables us to deduce an important result that an
evolving universe is related with a static universe by the gauge
transformation, i.e., they are gauge equivalent. This means that having a
different universe simply corresponds to choosing a different gauge

</DOC>
<DOC>
<DOCNO> 68788 </DOCNO>
N* Spectrum in Lattice QCD


  We investigate the mass of the parity partner $N^* (1/2^{-})$ of the nucleon
$N(1/2^{+})$, in lattice QCD using a new lattice discretization scheme for
fermions, domain wall fermions (DWF). DWF possess exact chiral symmetry and
flavor symmetry, both of which are required for this problem, even at finite
lattice spacing. Our calculation reproduces the large mass splitting between
those two states, in good agreement with experiment. We also present
preliminary results for the mass of the positive-parity excited state
$N'(1/2^{+})$.

</DOC>
<DOC>
<DOCNO> 12185 </DOCNO>
Role of bound pairs in the optical properties of highly excited


  Presence of bound pairs (excitons) in a low-temperature electron-hole plasma
is accounted for by including correlation between fermions at the ladder level.
Using a simplified one-dimensional model with on-site Coulomb interaction, we
calculate the one-particle self-energies, chemical potential, and optical
response. The results are compared to those obtained in the Born approximation,
which does not account for bound pairs. In the self-consistent ladder
approximation the self-energy and spectral function show a characteristic
correlation peak at the exciton energy for low temperature and density. In this
regime the Born approximation overestimates the chemical potential. Provided
the appropriate vertex correction in the interaction with the photon is
included, both ladder and Born approximations reproduce the excitonic and free
pair optical absorption at low density, and the disappearance of the exciton
absorption peak at larger density. However, lineshapes and energy shifts with
density of the absorption and photoluminescence peaks are drastically
different. In particular, the photoluminescence emission peak is much more
stable in the ladder approximation. At low temperature and density a sizeable
optical gain is produced in both approximations just below the excitonic peak,
however this gain shows unphysical features in the Born approximation. We
conclude that at low density and temperature it is fundamental to take into
account the existence of bound pairs in the electron-hole plasma for the
calculation of its optical and thermodynamic properties. Other approximations
that fail to do so are intrinsically unphysical in this regime, and for example
are not suitable to address the problem of excitonic lasing.

</DOC>
<DOC>
<DOCNO> 72313 </DOCNO>
A Warped Supersymmetric Standard Model


  We study the breaking of supersymmetry in five-dimensional (5d) warped
spaces, using the Randall-Sundrum model as a prototype. In particular, we
present a supersymmetry-breaking mechanism which has a geometrical origin, and
consists of imposing different boundary conditions between the fermions and
bosons living in the 5d bulk. The scale of supersymmetry breaking is
exponentially small due to the warp factor of the AdS metric. We apply this
mechanism to a supersymmetric standard model where supersymmetry breaking is
transmitted through the AdS bulk to matter fields confined on the Planck-brane.
This leads to a predictable superparticle mass spectrum where the gravitino
mass is $10^{-3}$eV and scalar particles receive masses at the one-loop level
via bulk gauge interactions. We calculate the mass spectrum in full detail
using the 5d AdS propagators. The AdS/CFT correspondence suggests that our 5d
warped model is dual to the ordinary 4d MSSM with a strongly coupled CFT sector
responsible for the breaking of supersymmetry.

</DOC>
<DOC>
<DOCNO> 120874 </DOCNO>
Particle-Mesh Simulations of the Lyman-Alpha Forest


  Numerical hydrodynamical simulations have proven a successful means of
reproducing many of the statistical properties of the Lyman-Alpha forest as
measured in high redshift quasar spectra. Pseudo-hydrodynamical methods based
only on simulating the dark matter component have been claimed to yield a
comparable level of success. We investigate the degree to which two
pseudo-methods, with and without allowing for a pseudo-gas pressure, are able
to match the predictions of fully hydrodynamical plus dark matter simulations.
We also address the requirements for convergence to the statistics of the
spectra and the inferred properties of the Lyman-Alpha forest as a function of
resolution and box size. Generally we find it is possible to reach agreement
with full hydrodynamic simulations at the 10% level in the cumulative
distributions of the flux and absorption line parameter statistics for readily
achievable particle and grid numbers, but difficult to do much better.

</DOC>
<DOC>
<DOCNO> 121190 </DOCNO>
The Luminosity Function of Magnitude and Proper-Motion Selected Samples.


  The luminosity function of white dwarfs is a powerful tool for studies of the
evolution and formation of the Milky Way. The (theoretical) white dwarf cooling
sequence provides a useful indicator of the evolutionary time scales involved
in the chronometry and star formation history of the galactic disk, therefore,
intrinsically faint (& old) white dwarfs in the immediate solar neighborhood
can be used to determine an upper limit for the age of the galactic disk.
  In this paper we examine the faint-end ($M_V > +14$) behavior of the disk
white dwarf luminosity function using the $1/V_{\rm max}$ method, but fully
including the effects of realistic observational errors in the derived
luminosity function. We employ a Monte Carlo approach to produce many different
realizations of the luminosity function from a given data set with
pre-specified and reasonable errors in apparent magnitude, proper-motions,
parallaxes and bolometric corrections. These realizations allow us to compute
both a mean and an expected range in the luminosity function that is compatible
with the observational errors.
  We find that current state-of-the art observational errors, mostly in the
bolometric corrections and trigonometric parallaxes, play a major role in
obliterating (real or artificial) small scale fluctuations in the luminosity
function. We also find that a better estimator of the true luminosity function
seems to be the median over simulations, rather than the mean. When using the
latter, an age for the disk of 10 Gyr or older can not be ruled out from the
sample of Leggett, Ruiz, and Bergeron (1998).

</DOC>
<DOC>
<DOCNO> 12925 </DOCNO>
States without linear counterpart in Bose-Einstein condensates


  We show the existence of stationary solutions of a 1-D Gross-Pitaevskii
equation in presence of a multi-well external potential that do not reduce to
any of the eigenfunctions of the associated Schroedinger problem. These
solutions, which in the limit of strong nonlinearity have the form of chains of
dark or bright solitons located near the extrema of the potential, represent
macroscopically excited states of a Bose-Einstein condensate and are in
principle experimentally observable.

</DOC>
<DOC>
<DOCNO> 120438 </DOCNO>
Ages and Metallicities of Globular Clusters in NGC 4472


  We have derived ages and metallicities from co-added spectra of 131 globular
clusters associated with the giant elliptical galaxy NGC 4472. Based upon a
calibration with Galactic globular clusters, we find that our sample of
globular clusters in NGC 4472 span a metallicity range of approximately -1.6 <=
[Fe/H] <= 0 dex. There is evidence of a radial metallicity gradient in the
globular cluster system, which is steeper than that seen in the underlying
starlight. Determination of the absolute ages of the globular clusters is
uncertain, but formally, the metal-poor population of globular clusters has an
age of 14.5 +/- 4 Gyr and the metal-rich population is 13.8 +/- 6 Gyr old.
Monte Carlo simulations indicate that the globular cluster populations present
in these data are older than 6 Gyr at the 95% confidence level. We find that
within the uncertainties, the globular clusters are old and coeval, implying
that the bimodality seen in the broadband colours primarily reflects
metallicity and not age differences.

</DOC>
<DOC>
<DOCNO> 102282 </DOCNO>
Transform\'ee de Mellin des int\'egrales-fibres associ\'ees aux


  The Mellin transform of fibre integral is calculated for certain isolated
singularities of quasihomogeneous complete intersections (especially the
unimodal singualrities of the list by Giusti and Wall). We show the property of
symmetry between spectra of Gauss-Manin and shed light on the lattice structure
of poles of the Mellin transform by means of topological data of the
singularity. As an application, Hodge numbers of the Milnor fibre are expressed
by counting the spectra of Gauss-Manin.

</DOC>
<DOC>
<DOCNO> 152196 </DOCNO>
Excision of Singularities by Stringy Domain Walls


  We study supersymmetric domain walls on S_1/Z_2 orbifolds. The supergravity
solutions in the bulk are given by the attractor equation associated with
Calabi-Yau spaces and have a naked space-time singularity at some |y_s|. We are
looking for possibilities to cut off this singularity with the second wall by a
stringy mechanism. We use the collapse of the CY cycle at |y_c| which happens
before and at a finite distance from the space-time singularity. In our example
with three Kahler moduli the second wall is at the end of the moduli space at
|y_c| where also the enhancement of SU(2) gauge symmetry takes place so that
|y_e|=|y_c|< |y_s|. The physics of the excision of a naked singularity via the
enhancon in the context of domain wall has an interpretation on the heterotic
side related to R -> 1/R duality. The position of the enhancon is given by the
equation R(|y_e|)=1.

</DOC>
<DOC>
<DOCNO> 71681 </DOCNO>
Stability of the perturbative vacuum against spatial variations of the


  We investigate the effective action of the Polyakov loop with spatial
variations. We expand the effective action not in powers of derivatives or
momenta, but in powers of variational amplitudes. At one-loop order the results
suggest that the instability towards the confining vacuum may be caused by the
variational terms.

</DOC>
<DOC>
<DOCNO> 13340 </DOCNO>
A thermodynamically self-consistent theory for the Blume-Capel model


  We use a self-consistent Ornstein-Zernike approximation to study the
Blume-Capel ferromagnet on three-dimensional lattices. The correlation
functions and the thermodynamics are obtained from the solution of two coupled
partial differential equations. The theory provides a comprehensive and
accurate description of the phase diagram in all regions, including the wing
boundaries in non-zero magnetic field. In particular, the coordinates of the
tricritical point are in very good agreement with the best estimates from
simulation or series expansion. Numerical and analytical analysis strongly
suggest that the theory predicts a universal Ising-like critical behavior along
the $\lambda$-line and the wing critical lines, and a tricritical behavior
governed by mean-field exponents.

</DOC>
<DOC>
<DOCNO> 12278 </DOCNO>
Single-electron soliton avalanches in tunnel junction arrays


  Numerical modeling of correlated single-electron tunneling in uniform 2D
arrays of small conducting islands separated by tunnel junctions shows the
possiblility of soliton-antisoliton avalanches. Though the time duration of any
avalanche, and the total charge $\Delta Q = ne$ transferred across the array
during the avalanche, are always finite, in arrays with length $N$ larger than
certain critical value $N_c$ and large width $M \gg f(N)$, the avalanche
magnitude $n$ may be exponentially large, resulting in particular in a giant
increase of shot noise. Thermal fluctuations and disorder gradually suppress
the avalanche effect.

</DOC>
<DOC>
<DOCNO> 101931 </DOCNO>
Magnetic fingerprints on the spectra of one-electron and two-electrons


  Magnetic fingerprints on the spectra of an interacting electron with a
negatively charged ion in a parabolic quantum dot (QD), and of two interacting
electrons in such a dot, are investigated via a pseudoperturbative methodical
proposal. The effect of ion-electron and electron-electron interactions on the
spectra are studied. The effect of the symmetry of such problem is emphasized.
Compared to those obtained by Zhu et al. [6], via a series solution, the
results are found in excellent accord. Higher excited - states are also
reported.

</DOC>
<DOC>
<DOCNO> 13778 </DOCNO>
Possible Effects of Spacetime Foam in Particle Physics


  We present an extension of quantum field theory to the case when the
spacetime topology fluctuates (spacetime foam). In this extension the number of
bosonic fields becomes a variable and the ground state is characterized by a
finite particle number density. It is shown that when the number of fields
remains a constant, the standard field theory is restored. However, in the
complete theory the ground state has a nontrivial properties. In particular, it
produces an increase in the level of quantum fluctuations in the field
potentials and an additional renormalization of masses of particles. We examine
fluctuations of massless fields and show that in the presence of a temperature
(thermal state) these fluctuations has 1/f spectrum. Thus, the main prediction
of the theory is that our universe should be filled with a random
electromagnetic field which should produce an additional 1/f - noise in
electric circuits.

</DOC>
<DOC>
<DOCNO> 120345 </DOCNO>
Sources of CMB Spots in Closed Hyperbolic Universes


  The results of a previous paper by the author [Astrophys. J. 470, 43 (1996)
are improved, through a more reliable technique for finding the location of
sources whose images are on the surface of last scattering.

</DOC>
<DOC>
<DOCNO> 120342 </DOCNO>
Metal Enrichment of The Primordial Interstellar Medium through 3-D


  The long-term evolution of supernova remnants (SNRs) in the primordial
interstellar medium (ISM) with an inhomogeneous structure is calculated to
investigate metal enrichment of the primordial gas. For this purpose, we have
constructed a parallel 3-D hydrodynamics code incorporating the radiative
cooling and self-gravity. The self-gravity and radiative cooling develop the
inhomogeneous structure of the ISM from a small perturbation with a power-law
spectrum. The resultant density ranges from 0.5 cm$^{-3}$ to 10$^6$ cm $^{-3}$.
Calculations for a supernova (SN) with the progenitor mass of 20 solar mass are
performed as the first step of a series of our study. It is found from the
results that a single SN distributes some of newly synthesized heavy elements
into a dense filament of the ISM with densities ranging from 100 to 10$^4$
cm$^{-3}$ depending on where the SN explodes. Thus, the metallicity [Mg/H] of
the dense filaments polluted by the SN ejecta becomes $-2.7\pm0.5$. From these
filaments, the first Population II stars will form. This value is in accordance
with the previous analytical work (Shigeyama & Tsujimoto 1998) with accuracy of
$\sim 0.3$ dex.

</DOC>
<DOC>
<DOCNO> 12772 </DOCNO>
Properties of a magnetic superconductor with weak magnetization -


  Using a Ginsburg-Landau free energy functional, we study the $H-T$ phase
diagram of a weak magnetic superconductor, where the magnetization from the
magnetic component is marginal in supporting a spontaneous vortex phase in
absence of external magnetic field. In particular, the competition between the
spiral state and spontaneous vortex phase is analysed. Our theory is applied to
understand the magnetic properties of $ErNi_2B_2C$.

</DOC>
<DOC>
<DOCNO> 119526 </DOCNO>
X-ray Fluctuations from the Slim Disk


  The responses of perturbations added into the optically thick,
advection-dominated accretion disk (ADAD), what we call the slim disk (SD), are
investigated through numerical simulations. Although it is proposed that the SD
is thermally stable, I find that a perturbation added into the disk is not
rapidly damped and moves through the disk in its free-fall time. After the
perturbation moves, the global structure of the disk does not vary very much.
These facts may account for the substantial variability of the X-ray
luminosities of stellar super-luminal jet sources (SLJSs) and Narrow-Line
Seyfert 1s (NLS1s).

</DOC>
<DOC>
<DOCNO> 170178 </DOCNO>
Quantum mechanical Carnot engine


  A cyclic thermodynamic heat engine runs most efficiently if it is reversible.
Carnot constructed such a reversible heat engine by combining adiabatic and
isothermal processes for a system containing an ideal gas. Here, we present an
example of a cyclic engine based on a single quantum-mechanical particle
confined to a potential well. The efficiency of this engine is shown to equal
the Carnot efficiency because quantum dynamics is reversible. The quantum heat
engine has a cycle consisting of adiabatic and isothermal quantum processes
that are close analogues of the corresponding classical processes.

</DOC>
<DOC>
<DOCNO> 83066 </DOCNO>
Characterization of Non-Deterministic Quantum Query and Quantum


  It is known that the classical and quantum query complexities of a total
Boolean function f are polynomially related to the degree of its representing
polynomial, but the optimal exponents in these relations are unknown. We show
that the non-deterministic quantum query complexity of f is linearly related to
the degree of a ``non-deterministic'' polynomial for f. We also prove a
quantum-classical gap of 1 vs. n for non-deterministic query complexity for a
total f. In the case of quantum communication complexity there is a (partly
undetermined) relation between the complexity of f and the logarithm of the
rank of its communication matrix. We show that the non-deterministic quantum
communication complexity of f is linearly related to the logarithm of the rank
of a non-deterministic version of the communication matrix, and that it can be
exponentially smaller than its classical counterpart.

</DOC>
<DOC>
<DOCNO> 122648 </DOCNO>
Damped Lyman-alpha absorption from a nearby Low Surface Brightness


  Ground-based & HST images of the nearby galaxy SBS 1543+593 (z=0.009) show it
to be a Low Surface Brightness (LSB) galaxy with a central surface brightness
of mu_B(0)=23.2 mag/arcsec-2 and scale length 0.9 h-1 kpc, values typical for
the local LSB galaxy population. The galaxy lies directly in front of the QSO
HS 1543+5921 (z=0.807); an HST STIS spectrum of the quasar reveals a damped
Lyman-alpha (DLA) line at the redshift of the interloper with an HI column
density of log N(HI) = 20.35, as well as several low-ionization metal lines
with strengths similar to those found in the Milky Way interstellar medium. Our
data show that LSB galaxies are certainly able to produce the DLA lines seen at
higher redshift, and fuels the speculation that LSB galaxies are a major
contributor to that population of absorbers.

</DOC>
<DOC>
<DOCNO> 12042 </DOCNO>
Dynamics of metastable vortex states in weakly pinned superconductors: A


  We present a phenomenological model for the vortex dynamics in the peak
effect region of weakly pinned superconductors. We explain the history
dependent dynamic response of the metastable vortex states subjected to a
transport current and the hysteretic voltage-current characteristics observed
in the vicinity of peak effect in weakly pinned superconductors. A strong
variation in voltage current characteristics with the current sweep rate and
the anomalous dependence of critical current density $J_c$ on the magnetic
field sweep rate have also been accounted for by this model.

</DOC>
<DOC>
<DOCNO> 151639 </DOCNO>
Truncation of functional relations in the XXZ model


  This is the abstract of the revised paper. The integrable XXZ model with a
special open boundary condition is considered. We study Sklyanin transfer
matrices after quantum group reduction in roots of unity. In this case Sklyanin
transfer matrices satisfy a closed system of truncated functional equations.
The algebraic reason for the truncation is found.The important role in proving
of the result is performed by Zamolodchikov algebra introduced in the paper.

</DOC>
<DOC>
<DOCNO> 69565 </DOCNO>
Bulk Higgs Boson Decays in Brane Localized Gravity


  We embed the Standard Model in the Randall-Sundrum model of 5 dimensional
brane localized gravity. The SM gauge and chiral fermion fields are restricted
on the 4D visible brane whereas the Higgs and the right-handed neutrino are
assumed to be 5D bulk fields. We calculate the effective couplings of the
lowest mass Higgs field to the SM fermions and to the gauge bosons and find
that the couplings are enhanced. Furthermore, the invisible decay width of a
bulk Higgs of mass 150 GeV is shown to be large.

</DOC>
<DOC>
<DOCNO> 122546 </DOCNO>
Constraints in the lambda_0-Omega_0 plane from gravitational lensing


  I review simultaneous constraints on the cosmological parameters lambda_0 and
Omega_0 from gravitational lensing. The emphasis is on systematic extragalactic
surveys for strong gravitational lenses, mainly the largest and best-defined
such survey, JVAS/CLASS.

</DOC>
<DOC>
<DOCNO> 120762 </DOCNO>
Observation of Optical Flashes of the Night Star Sky on the Atmospheric


  Experiment on the study of fluctuation of night glow is conducted on the base
of 13 module atmospheric Cherenkov telescope TUNKA-13.Basic task of TUNKA-13 is
registration of light from Extended Air Shower (EAS) initiated by primary
cosmic particles. Observation of light flashes radiating in nigght atmosphere
is one more experiment which is run for TUNKA-13 to study the background
condition for EAS registration. At a period from December 1997 on a May 1998
was registered 149 light flashes of radiwting night atmosphere with duration
from 16 ms to 190 seconds. General time of night observing has formed 237
hours. Coincidence of optical flashes with the gamma-bursts from the catalogue
of BATSE experiment of observatories "Compton" was analysed.

</DOC>
<DOC>
<DOCNO> 12308 </DOCNO>
Lanczos Study of the S=1/2 Frustrated Square-Lattice Antiferromagnet in


  We study the zero-temperature phase diagram of the frustrated square-lattice
S=1/2 antiferromagnet in an external magnetic field numerically with the
Lanczos algorithm. For strong frustration, we find disordered phases at high
(and low) magnetic fields. Between these two disordered phases we find a
plateau in the magnetization curve at half of the saturation magnetization
which corresponds to a state with up-up-up-down (uuud) spin order. This and
other considerations [cond-mat/0003343] suggest an unusual ordering scenario:
There are an ordered phase with a spin gap (the plateau) and disordered
magnetically gapless phases above and below.
   The transition to saturation is studied in further detail and problematic
conclusions in earlier investigations of this region are pointed out.

</DOC>
<DOC>
<DOCNO> 118552 </DOCNO>
The pattern speed of the nuclear disk of M31 using a variant of the


  The twin peaks in the nucleus of M31 have been interpreted by Tremaine as a
thick, eccentric, disk of stars orbiting a massive dark object; the required
alignment of the apoapsides of the stellar orbits could be maintained by
self-gravity, and the whole structure might be a discrete, nonlinear eigenmode.
The pattern speed of this mode could, in principle, be determined by the
Tremaine-Weinberg (TW) method, which requires measurements of the surface
brightness, and radial velocity along a strip parallel to the line of nodes.
However, spectroscopic observations along the line of nodes are not available.
We propose a variant of the TW method, which exploits a basic feature of the
eccentric disk model, to extract estimates of the pattern speed from {\it
Hubble Space Telescope} spectroscopic data, taken along the line joining the
two peaks. Within limitations imposed by the data, we estimate that the pattern
rotates in a prograde manner and, for an assumed disk inclination of
$77^{\circ}$, the pattern speed $|\Omega_p| < 30 {\rm km s^{-1} pc^{-1}}$, or
period more than $200,000$ years.

</DOC>
<DOC>
<DOCNO> 99834 </DOCNO>
Semiinfinite cohomology of Tate Lie algebras


  In this note we give a definition of semiinfinite cohomology for Tate Lie
algebras using the language of Differential Graded Lie algebroids with
Curvature (CDG Lie algebroids).

</DOC>
<DOC>
<DOCNO> 9774 </DOCNO>
Charge-Density-Wave induced modifications to the quasiparticle


  The self-energy of the photo-hole in 2H-TaSe2 is measured by angle-resolved
photoemission spectroscopy (ARPES) as a function of binding energy and
temperature. In the charge-density wave (CDW) state, a structure in the self-
energy is detected at ~ 65 meV that can not be explained by electron-phonon
scattering. A reduction in the scattering rates below this energy indicates the
collapse of a major scattering channel with the formation of the CDW state,
accompanying the appearance of a bosonic "mode" in the excitation spectrum of
the system.

</DOC>
<DOC>
<DOCNO> 12645 </DOCNO>
Glassy effects in the swelling/collapse dynamics of homogeneous polymers


  We investigate, using numerical simulations and analytical arguments, a
simple one dimensional model for the swelling or the collapse of a closed
polymer chain of size N, representing the dynamical evolution of a polymer in a
\Theta-solvent that is rapidly changed into a good solvent (swelling) or a bad
solvent (collapse). In the case of swelling, the density profile for
intermediate times is parabolic and expands in space as t^{1/3}, as predicted
by a Flory-like continuum theory. The dynamics slows down after a time \propto
N^2 when the chain becomes stretched, and the polymer gets stuck in metastable
`zig-zag' configurations, from which it escapes through thermal activation. The
size of the polymer in the final stages is found to grow as \sqrt{\ln t}. In
the case of collapse, the chain very quickly (after a time of order unity)
breaks up into clusters of monomers (`pearls'). The evolution of the chain then
proceeds through a slow growth of the size of these metastable clusters, again
evolving as the logarithm of time. We enumerate the total number of metastable
states as a function of the extension of the chain, and deduce from this
computation that the radius of the chain should decrease as 1/\ln(\ln t). We
compute the total number of metastable states with a given value of the energy,
and find that the complexity is non zero for arbitrary low energies. We also
obtain the distribution of cluster sizes, that we compare to simple
`cut-in-two' coalescence models. Finally, we determine the aging properties of
the dynamical structure. The subaging behaviour that we find is attributed to
the tail of the distribution at small cluster sizes, corresponding to
anomalously `fast' clusters (as compared to the average). We argue that this
mechanism for subaging might hold in other slowly coarsening systems.

</DOC>
<DOC>
<DOCNO> 9429 </DOCNO>
Local electronic properties of single wall nanotube circuits measured by


  We use conducting-tip atomic force microscopy (AFM) to measure local
electronic properties of single wall carbon nanotube (SWNT) circuits on
insulating substrates. When a voltage is applied to the tip and AFM feedback is
used to position the tip, images formed from the tip-sample tunnel current have
single tube resolution (near 1 nm diameter), more than an order of magnitude
better than simultaneously acquired topographic AFM images. By finding points
where the tip-sample current is zero, it is possible to measure the
electrochemical potential within the circuit, again with nanometer resolution.
Such measurements provide compelling evidence that nanotubes within a bundle
have only weak electronic coupling. Finally the AFM tip is used as a local
electrostatic gate, and the gating action can be correlated with the structure
of the SWNT bundle sample. This technique should be useful for a broad range of
circuits containing SWNTs and other molecules.

</DOC>
<DOC>
<DOCNO> 117913 </DOCNO>
Cyclotron lines in X-ray pulsars as a probe of relativistic plasmas in


  The systematic search for the presence of cyclotron lines in the spectra of
accreting X-ray pulsars is being carried on with the BeppoSAX satellite since
the beginning of the mission. These highly successful observations allowed the
detection of cyclotron lines in many of the accreting X-ray pulsars observed.
Some correlations between the different measured parameters were found. We
present these correlations and discuss them in the framework of the current
theoretical scenario for the X-ray emission from these sources.

</DOC>
<DOC>
<DOCNO> 71791 </DOCNO>
Possible candidate of the cold dark matter and mass origin discovered


  This paper has been withdrawn by the author(s) since somebody do not agree
with my idea.

</DOC>
<DOC>
<DOCNO> 151544 </DOCNO>
Cosmological Breaking of Supersymmetry?


  It is conjectured that M-theory in asymptotically flat spacetime must be
supersymmetric, and that the observed SUSY breaking in the low energy world
must be attributed to the existence of a nonzero cosmological constant. This
would be consistent with experiment, if the {\it critical exponent} $\alpha$ in
the relation $M_{SUSY} \sim M_P (\Lambda /M_P^4)^{\alpha}$ took on the value
1/8, rather than its classical value 1/4. We attribute this large
renormalization to the effect of large virtual black holes via the UV/IR
correspondence.

</DOC>
<DOC>
<DOCNO> 85203 </DOCNO>
Information Erasure and the Generalized Second Law of Black Hole


  We consider the generalized second law of black hole thermodynamics in the
light of quantum information theory, in particular information erasure and
Landauer's principle (namely, that erasure of information produces at least the
equivalent amount of entropy). A small quantum system outside a black hole in
the Hartle-Hawking state is studied, and the quantum system comes into thermal
equilibrium with the radiation surrounding the black hole. For this scenario,
we present a simple proof of the generalized second law based on quantum
relative entropy. We then analyze the corresponding information erasure
process, and confirm our proof of the generalized second law by applying
Landauer's principle.

</DOC>
<DOC>
<DOCNO> 101471 </DOCNO>
Representability for some moduli stacks of framed sheaves


  We prove a representability theorem for the restriction morphism from the
moduli stack of torsion-free sheaves on a complex projective surface S to the
moduli stack of vector bundles on a curve D in S. We obtain as a consequence
that two kinds of moduli stacks of framed sheaves on S are represented by
schemes.

</DOC>
<DOC>
<DOCNO> 123204 </DOCNO>
Compression and Classification Methods for Galaxy Spectra in Large


  Methods for compression and classification of galaxy spectra, which are
useful for large galaxy redshift surveys (such as the SDSS, 2dF, 6dF and
VIRMOS), are reviewed. In particular, we describe and contrast three methods:
(i) Principal Component Analysis, (ii) Information Bottleneck, and (iii) Fisher
Matrix. We show applications to 2dF galaxy spectra and to mock semi-analytic
spectra, and we discuss how these methods can be used to study physical
processes of galaxy formation, clustering and galaxy biasing in the new large
redshift surveys.

</DOC>
<DOC>
<DOCNO> 151476 </DOCNO>
Black Hole Thermodynamics from Calculations in Strongly-Coupled Gauge


  We develop an approximation scheme for the quantum mechanics of N D0-branes
at finite temperature in the 't Hooft large-N limit. The entropy of the quantum
mechanics calculated using this approximation agrees well with the
Bekenstein-Hawking entropy of a ten-dimensional non-extremal black hole with
0-brane charge. This result is in accord with the duality conjectured by
Itzhaki, Maldacena, Sonnenschein and Yankielowicz. Our approximation scheme
provides a model for the density matrix which describes a black hole in the
strongly-coupled quantum mechanics.

</DOC>
<DOC>
<DOCNO> 72007 </DOCNO>
QED Test at LEP200 Energies in the Reaction $\rm e^+ e^-\to \gamma\gamma


  The measurements of the QED reaction $ \EEGG $ performed with the L3 detector
are used to search for new physics phenomena beyond the Standard Model. No
evidence for these phenomena is found and new limits on their parameters are
set. First the reaction is used to constrain a model of an excited electron and
second to study contact interactions. The total and differential cross sections
for the process $ \EEGG $, are measured at energies from 91 GeV to 202 GeV
using the data collected with the L3 detector from 1991 to 1999. The L3 data
set lower limits on the mass of an excited electron $ \MESTAR > 402 $ GeV, on
the QED cutoff parameters $ \LAMP > 415 $ GeV, $ \LAMM > 258 $ GeV and on the
contact interaction energy scale $ \Lambda > 1687 $ GeV. The last parameter
limits the size of the interaction area to $ R < 1.17\times 10^{-17} $ cm. Some
limits on the string and quantum gravity scales are also discussed.

</DOC>
<DOC>
<DOCNO> 120123 </DOCNO>
A unified formalism for the core mass-luminosity relations of


  The luminosity evolution of stars with highly condensed cores surrounded by
nuclear-burning shell(s) is analytically investigated with the aid of homology
relations. With respect to earlier works using a similar approach (e.g. Refsdal
& Weigert 1970; Kippenhahn 1981), the major improvement is that we derive all
the basic dependences (i.e. on core mass, core radius, and chemical
composition) in a completely generalised fashion, then accounting for a large
range of possible physical properties characterising the burning shell(s).
Parameterised formulas for the luminosity are given as a function of the (i)
relative contribution of the gas to the total pressure (gas plus radiation),
(ii) opacity source, and (iii) dominant nuclear reaction rates. In this way,
the same formalism can be applied to shell-burning stars of various
metallicities and in different evolutionary phases. In particular, we present
some applications concerning the luminosity evolution of RGB and AGB stars with
different chemical compositions, including the case of initial zero
metallicity. It turns out that homology predictions provide a good
approximation to the results of stellar model calculations. Therefore, the
proposed formalism is useful to understand the possible differences in the
luminosity evolution of shell-burning stars within a unified interpretative
framework, and can be as well adopted to improve the analytical description of
stellar properties in synthetic models.

</DOC>
<DOC>
<DOCNO> 102120 </DOCNO>
Absolutely rigid systems and absolutely indecomposable groups


  We give a new proof that there are arbitrarily large indecomposable abelian
groups; moreover, the groups constructed are absolutely indecomposable, that
is, they remain indecomposable in any generic extension. However, any
absolutely rigid family of groups has cardinality less than the partition
cardinal kappa(omega).

</DOC>
<DOC>
<DOCNO> 68360 </DOCNO>
Muon colliders and the non-perturbative dynamics of the Higgs boson


  A muon collider operating in the TeV energy range can be an ideal s-channel
Higgs boson factory. This is especially true for a heavy Higgs boson. The
non-perturbative dynamical aspects of such a Higgs boson were recently
investigated with large N expansion methods at next to leading order, and
reveal the existence of a mass saturation effect. Even at strong coupling, the
Higgs resonance remains always below 1 TeV. However, if the coupling is strong
enough, the resonance becomes impossible to be detected.

</DOC>
<DOC>
<DOCNO> 10297 </DOCNO>
Large Scale-Invariant Fluctuations in Normal Blood Cell Counts: A sign


  All types of blood cells are formed by differentiation from a small
self-maintaining population of pluri-potential stem cells in the bone marrow.
Despite abundant information on the molecular aspects of division,
differentiation, commitment and maturation of these cells, comparatively little
is known about the dynamics of the system as a whole, and how it works to
maintain this complex ``ecology'' in the observed normal ranges throughout
life. Here we report unexpected large, scale-free, fluctuations detected from
the first long-term analysis of the day-to-day variability of a healthy
animal's blood cell counts measured over one thousand days. This
scale-invariance cannot be accounted for by current theoretical models, and
resembles some of the scenarios described for self-organized criticality.

</DOC>
<DOC>
<DOCNO> 69484 </DOCNO>
The g-2 of the Muon in Localized Gravity Models


  The (g-2) of the muon is well known to be an important model building
constraint on theories beyond the Standard Model. In this paper, we examine the
contributions to $(g-2)_\mu$ arising in the Randall-Sundrum model of localized
gravity for the case where the Standard Model gauge fields and fermions are
both in the bulk. Using the current experimental world average measurement for
$(g-2)_\mu$, we find that strong constraints can be placed on the mass of the
lightest gauge Kaluza-Klein excitation for a narrow part of the allowed range
of the assumed universal 5-dimensional fermion mass parameter, $\nu$. However,
employing both perturbativity and fine-tuning constraints we find that we can
further restrict the allowed range of the parameter $\nu$ to only one fourth of
its previous size. The scenario with the SM in the RS bulk is thus tightly
constrained, being viable for only a small region of the parameter space.

</DOC>
<DOC>
<DOCNO> 83258 </DOCNO>
A Note on "Optimal Static Load Balancing in Distributed Computer


  The problem of minimizing mean response time of generic jobs submitted to a
heterogenous distributed computer systems is considered in this paper. A static
load balancing strategy, in which decision of redistribution of loads does not
depend on the state of the system, is used for this purpose. The article is
closely related to a previous article on the same topic. The present article
points out number of inconsistencies in the previous article, provides a new
formulation, and discusses the impact of new findings, based on the improved
formulation, on the results of the previous article.

</DOC>
<DOC>
<DOCNO> 179023 </DOCNO>
Photoproduction of quasi-bound omega mesons in nuclei


  We propose the (gamma,p) reaction as a means of producing possible
quasi-bound states of omega mesons in nuclei. We use an effective Lagrangian,
based on chiral SU(3) symmetry and vector meson dominance, in order to
construct the omega-nuclear potential. The contribution of bound omega states
is observable in the missing energy spectra of protons emitted in forward
direction for several nuclei.

</DOC>
<DOC>
<DOCNO> 84128 </DOCNO>
Noncommutative Unification of General Relativity with Quantum Mechanics


  The groupoid approach to noncommutative unification of general relativity
with quantum mechanics is compared with the canonical gravity quantization. It
is shown that by restricting the corresponding noncommutative algebra to its
(commutative) subalgebra, which determines the space-time slicing, an algebraic
counterpart of superspace (space of 3-metrics) can be obtained. It turns out
that when this space-time slicing emerges the universe is already in its
commutative regime. We explore the consequences of this result.

</DOC>
<DOC>
<DOCNO> 122098 </DOCNO>
Non-linearity and Non-Gaussianity through Phase Information


  In the standard picture of structure formation, initially random-phase
fluctuations are amplified by non-linear gravitational instability to produce a
final distribution of mass which is highly non-Gaussian and has highly coupled
Fourier phases. Second-order statistics, such as the power spectrum, are blind
to this kind of phase association. We discuss the information contained in the
phases of cosmological density fluctuations and their possible use in
statistical analysis tools. In particular, we show how the bispectrum measures
a particular form of phase association called quadratic phase coupling, show
how to visualise phase association using colour models. These techniques offer
the prospect of more complete tests of initial non-Gaussianity than those
available at present.

</DOC>
<DOC>
<DOCNO> 123322 </DOCNO>
Generation and Acceleration of Jets from Effective Boundary Layer around


  We propose the processes of generation and radiative acceleration of jets
from the centrifugal pressure dominated boundary layer around a black hole.

</DOC>
<DOC>
<DOCNO> 8170 </DOCNO>
Numerical analyses of the nonequilibrium electron transport through the


  Nonequilibrium electron transport through the Kondo impurity is investigated
numerically for the system with twenty conduction-electron levels. The electron
current under finite voltage drop is calculated in terms of the `conductance
viewed as transmission' picture proposed by Landauer. Here, we take into
account the full transmission processes of both the many-body correlation and
the hybridization amplitude up to infinite order. Our results demonstrate, for
instance, how the exact solution of the differential conductance by Schiller
and Hershfield obtained at the Toulouse point becomes deformed by more
realistic interactions. The differential-conductance-peak height is suppressed
below e^2/h with the width hardly changed through reducing the Kondo coupling
from the Toulouse point, whereas it is kept unchanged by further increase of
the coupling. We calculated the nonequilibrium local Green function as well.
This clarifies the spectral property of the Kondo impurity driven far from
equilibrium.

</DOC>
<DOC>
<DOCNO> 9818 </DOCNO>
Anisotropic conductivity of Nd_{1.85}Ce_{0.15}CuO_{4-\delta} films at


  The anisotropic conductivity of thin Nd$_{1.85}$Ce$_{0.15}$CuO$_{4-\delta}$
films was measured in the frequency range 8 cm$^{-1}<\nu <$ 40 cm$^{-1}$ and
for temperatures 4 K $<T<300$ K. A tilted sample geometry allowed to extract
both, in-plane and c-axis properties. The in-plane quasiparticle scattering
rate remains unchanged as the sample becomes superconducting. The temperature
dependence of the in-plane conductivity is reasonably well described using the
Born limit for a d-wave superconductor. Below $T_{{\rm C}%}$ the c-axis
dielectric constant $\epsilon_{1c}$ changes sign at the screened c-axis plasma
frequency. The temperature dependence of the c-axis conductivity closely
follows the linear in T behavior within the plane.

</DOC>
<DOC>
<DOCNO> 102149 </DOCNO>
Novikov-Morse theory for dynamical systems


  The present paper contains an interpretation and generalization of Novikov's
theory of Morse type inequalities for 1-forms in terms of Conley's theory for
dynamical systems.

</DOC>
<DOC>
<DOCNO> 11624 </DOCNO>
Storage Capacity of the Tilinglike Learning Algorithm


  The storage capacity of an incremental learning algorithm for the parity
machine, the Tilinglike Learning Algorithm, is analytically determined in the
limit of a large number of hidden perceptrons. Different learning rules for the
simple perceptron are investigated. The usual Gardner-Derrida one leads to a
storage capacity close to the upper bound, which is independent of the learning
algorithm considered.

</DOC>
<DOC>
<DOCNO> 116914 </DOCNO>
Toutatis, the Cea-Saclay RFQ code


  A CW high power linear accelerator can only work with very low particles
losses and structure activation. At low energy, the RFQ is a very sensitive
element to losses. To design the RFQ, a good understanding of the beam dynamics
is requested. Generally, the reference code PARMTEQM is enough to design the
accelerator. TOUTATIS has been written with goals of cross-checking results and
obtaining a more reliable dynamics. This paper relates the different numerical
methods used in the code. It is time-based, using multigrids methods and
adaptive mesh for a fine description of the forces without being time
consuming.
 The field is accurately calculated through a Poisson solver and the vanes are
fully described, allowing to properly simulate the coupling gaps and RFQs
extremities. Differences with PARMTEQM and LIDOS.RFQ are shown.

</DOC>
<DOC>
<DOCNO> 118861 </DOCNO>
DIRBE Minus 2MASS: Confirming the Cosmic Infrared Background at 2.2


  Stellar fluxes from the 2MASS catalog are used to remove the contribution due
to Galactic stars from the intensity measured by DIRBE in four regions in the
North and South Galactic polar caps. After subtracting the interplanetary and
galactic foregrounds, a consistent residual intensity of 14.8 +/- 4.6 kJy/sr or
20.2 +/- 6.3 nW/m^2/sr at 2.2 microns is found. At 1.25 microns the residuals
show more scatter and are a much smaller fraction of the foreground, leading to
a weak limit on the CIRB of 12.0 +/- 6.8 kJy/sr or 28.9 +/- 16.3 nW/m^2/sr (1
sigma).

</DOC>
<DOC>
<DOCNO> 9396 </DOCNO>
Spectacular decrease of the melting magnetic field in the charge-ordered


  An insulator to metal transition below 240K is induced by applying a 7T
magnetic field in Pr0.5Ca0.5MnO3 thin films grown by the Pulsed Laser
Deposition technique on (100) SrTiO3 substrates. This value of the melting
magnetic field, much lower that the one required in bulk (20T), is assumed to
be an effect of the tensile stress. These results confirm the importance of the
bandwidth in the control of the physical properties of this compound and open
the route to get colossal magnetoresistive properties by using strain effects.

</DOC>
<DOC>
<DOCNO> 121520 </DOCNO>
H_0 from gravitational lenses: recent results


  The 0th, 1st and 2nd derivatives of a ``Fermat potential'' give the three D's
of gravitational lensing: delay, deflection and distortion. Observations of
these delays, deflections and distortions for doubly and quadruply imaged
quasars give estimates of Hubble's constant, H_0. The single largest
contribution to the uncertainty in H_0 arises from the difficulty in
constraining the degree of central concentration of the lensing potential.
Fortunately, astronomers have spent a good deal of effort over the past quarter
century addressing just this question. If galaxies at z=0.5 are like nearby
galaxies, the associated systematic uncertainty in H_0 is less than 10%. The
expected lens-to-lens scatter is 20%. Results from three particularly well
constrained systems are reported.

</DOC>
<DOC>
<DOCNO> 71873 </DOCNO>
Electron Scattering with Polarized Targets at TESLA


  Measurements of polarized electron-nucleon scattering can be realized at the
TESLA linear collider facility with projected luminosities that are about two
orders of magnitude higher than those expected of other experiments at
comparable energies. Longitudinally polarized electrons, accelerated as a small
fraction of the total current in the e+ arm of TESLA, can be directed onto a
solid state target that may be either longitudinally or transversely polarized.
A large variety of polarized parton distribution and fragmentation functions
can be determined with unprecedented accuracy, many of them for the first time.
A main goal of the experiment is the precise measurement of the x- and
Q^2-dependence of the experimentally totally unknown quark transversity
distributions that will complete the information on the nucleon's quark spin
structure as relevant for high energy processes. Comparing their Q^2-evolution
to that of the corresponding helicity distributions constitutes an important
precision test of the predictive power of QCD in the spin sector. Measuring
transversity distributions and tensor charges allows access to the hitherto
unmeasured chirally odd operators in QCD which are of great importance to
understand the role of chiral symmetry. The possibilities of using unpolarized
targets and of experiments with a real photon beam turn TESLA-N into a
versatile next-generation facility at the intersection of particle and nuclear
physics.

</DOC>
<DOC>
<DOCNO> 9332 </DOCNO>
Stable 85Rb Bose-Einstein Condensates with Widely Tunable Interactions


  Bose-Einstein condensation has been achieved in a magnetically trapped sample
of 85Rb atoms. Long-lived condensates of up to 10^4 atoms have been produced by
using a magnetic-field-induced Feshbach resonance to reverse the sign of the
scattering length. This system provides many unique opportunities for the study
of condensate physics. The variation of the scattering length near the
resonance has been used to magnetically tune the condensate self-interaction
energy over a very wide range. This range extended from very strong repulsive
to large attractive self-interactions. When the interactions were switched from
repulsive to attractive, the condensate shrank to below our resolution limit,
and after ~5 ms emitted a burst of high-energy atoms.

</DOC>
<DOC>
<DOCNO> 100026 </DOCNO>
Gerbes of chiral differential operators. II


  Results of our previous note, "Gerbes of chiral differential operators"
(Math. Res. Letters, 7(2000), 55-66), are discussed in the algebraic category.

</DOC>
<DOC>
<DOCNO> 151746 </DOCNO>
Covariant Quantization of the Superstring


  After reviewing the Green-Schwarz superstring using the approach of Siegel,
the superstring is covariantly quantized by constructing a BRST operator from
the fermionic constraints and a bosonic pure spinor ghost variable. Physical
massless vertex operators are constructed and, for the first time, N-point tree
amplitudes are computed in a manifestly ten-dimensional super-Poincar\'e
covariant manner. Quantization can be generalized to curved supergravity
backgrounds and the vertex operator for fluctuations around $AdS_5\times S^5$
is explicitly constructed. This review is written in a self-contained manner
and is based on talks given at the Fradkin Memorial Conference and Strings
2000.

</DOC>
<DOC>
<DOCNO> 13308 </DOCNO>
Global Optimization and the Energy Landscapes of Dzugutov Clusters


  The global minima of clusters bound by a Dzugutov potential form non-compact
polytetrahedral clusters mainly composed of interpenetrating and face-sharing
13-atom icosahedra. As the size increases, these icosahedral units first form
linear arrays, then two-dimensional rings, then three-dimensional networks.
Characterization of the energy landscapes of these clusters shows that they are
particularly rough and generally exhibit a multiple-funnel topography. These
results provide new insights into the structure and dynamics of bulk
supercooled Dzugutov liquids and the form of the bulk phase diagram.

</DOC>
<DOC>
<DOCNO> 150361 </DOCNO>
Open-string models with broken supersymmetry


  I review the salient features of three classes of open-string models with
broken supersymmetry. These suffice to exhibit, in relatively simple settings,
the two phenomena of ``brane supersymmetry'' and ``brane supersymmetry
breaking''. In the first class of models, to lowest order supersymmetry is
broken both in the closed and in the open sectors. In the second class of
models, to lowest order supersymmetry is broken in the closed sector, but is
{\it exact} in the open sector, at least for the low-lying modes, and often for
entire towers of string excitations. Finally, in the third class of models, to
lowest order supersymmetry is {\it exact} in the closed (bulk) sector, but is
broken in the open sector. Brane supersymmetry breaking provides a natural
solution to some old difficulties met in the construction of open-string vacua.

</DOC>
<DOC>
<DOCNO> 85285 </DOCNO>
The fate of chaotic binaries


  A typical stellar mass black hole with a lighter companion is shown to
succumb to a chaotic precession of the orbital plane. As a result, the optimal
candidates for the direct detection of gravitational waves by Earth based
interferometers can show irregular modulation of the waveform during the last
orbits before plunge. The precession and the subsequent modulation of the
gravitational radiation depends on the mass ratio, eccentricity, and spins. The
smaller the mass of the companion, the more prominent the effect of the
precession. The most important parameters are the spin magnitudes and
misalignments. If the spins are small and nearly aligned with the orbital
angular momentum, then there will be no chaotic precession while increasing
both the spin magnitudes and misalignments increases the erratic precession. A
large eccentricity can be induced by large, misaligned spins but does not seem
to be required for chaos. An irregular precession of the orbital plane will
generate irregularities in the gravitational wave frequency but may have a
lesser effect on the total number of cycles observed.

</DOC>
<DOC>
<DOCNO> 119950 </DOCNO>
On the Origin of the Iron K Line in the Spectrum of the Galactic X-ray


  We propose a mechanism for the origin of the Galactic ridge X-ray background
that naturally explains the properties of the Fe K line, specifically the
detection of the centroid line energy below 6.7 keV and the apparent broadness
of the line. Motivated by recent evidence of nonthermal components in the
spectrum of the Galactic X-ray/gamma-ray background, we consider a model that
is a mixture of thermal plasma components of perhaps supernova origin and
nonthermal emission from the interaction of low energy Cosmic ray electrons
(LECRe) with the interstellar medium. The LECRe may be accelerated in supernova
explosions or by ambient interstellar plasma turbulence. Atomic collisions of
fast electrons produce characteristic nonthermal, narrow X-ray emission lines
that can explain the complex Galactic background spectrum. Using the ASCA GIS
archival data from the Scutum arm region, we show that a two-temperature
thermal plasma model with kT~0.6 and ~2.8 keV, plus a LECRe component models
the data satisfactorily. Our analysis rules out a purely nonthermal origin for
the emission. It also rules out a significant contribution from low energy
Cosmic ray ions, because their nonthermal X-ray production would be accompanied
by a nuclear gamma-ray line diffuse emission exceeding the upper limits
obtained using OSSE, as well as by an excessive Galaxy-wide Be production rate.
The proposed model naturally explains the observed complex line features and
removes the difficulties associated with previous interpretations of the data
which evoked a very hot thermal component (kT~7 keV).

</DOC>
<DOC>
<DOCNO> 11758 </DOCNO>
Multiple energy x-ray holography: the polarization effect


  We present the theory for Multiple Energy X-ray Holography (MEXH), using a
multipole expansion for the scattered field. We find that light polarization
plays a crucial role in the reconstruction of the image, and we suggest how to
use it in order to eliminate aberration effects. The method we propose is
alternative to the SWIFT method (scattered-wave--included Fourier transform),
but has the advantage that no theoretical calculations are required to redefine
the hologram.

</DOC>
<DOC>
<DOCNO> 9019 </DOCNO>
Quantum renormalization of high energy excitations in the 2D Heisenberg


  We find using Monte Carlo simulations of the spin-1/2 2D square lattice
nearest neighbour quantum Heisenberg antiferromagnet that the high energy peak
locations at (pi,0) and (pi/2,pi/2) differ by about 6%, (pi/2,pi/2) being the
highest. This is a deviation from linear spin wave theory which predicts equal
magnon energies at these points.

</DOC>
<DOC>
<DOCNO> 152374 </DOCNO>
Probing Some N=1 AdS/CFT RG Flows


  We present the results of probing the ten dimensional type IIB supergravity
solution corresponding to a renormalisation group flow of supersymmetric SU(n)
Yang-Mills theory from pure gauge N=4 to N=1 with two massless adjoint
flavours. The endpoint of the flow is an infrared fixed point theory, and
because of this simplicity of the theory, the effective Lagrangian for the
probe is very well-behaved, having no zeros or singularities in the tension,
and a smooth potential, all of which we exhibit. Specialising to the locus of
points where the potential vanishes, we also characterise a part of the Coulomb
branch of the N=1 theory. The simplicity of the gauge theory physics allows us
to isolate and emphasise a key holographic feature of brane probe physics which
has wider applications in the study of geometry/gauge theory duals.

</DOC>
<DOC>
<DOCNO> 12270 </DOCNO>
Metal-insulator transition in anisotropic systems


  We study the three-dimensional Anderson model of localization with
anisotropic hopping, i.e., weakly coupled chains and weakly coupled planes. In
our extensive numerical study we identify and characterize the metal-insulator
transition by means of the transfer-matrix method and energy level statistics.
Using high accuracy data for large system sizes we estimate the critical
exponent as \nu=1.6 +/- 0.3. This is in agreement with its value in the
isotropic case and in other models of the orthogonal universality class.

</DOC>
<DOC>
<DOCNO> 7939 </DOCNO>
Shot noise of Coulomb drag current


  We work out a theory of shot noise in a special case. This is a noise of the
Coulomb drag current excited under the ballistic transport regime in a
one-dimensional nanowire by a ballistic non-Ohmic current in a nearby parallel
nanowire. We predict sharp oscillation of the noise power as a function of gate
voltage or the chemical potential of electrons. We also study dependence of the
noise on the voltage V across the driving wire. For relatively large values of
V the noise power is proportional to V^2.

</DOC>
<DOC>
<DOCNO> 102869 </DOCNO>
A mass formula for unimodular lattices with no roots


  We derive a mass formula for n-dimensional unimodular lattices having any
prescribed root system. We use Katsurada's formula for the Fourier coefficients
of Siegel Eisenstein series to compute these masses for all root systems of
even unimodular 32-dimensional lattices and odd unimodular lattices of
dimension n < 31. In particular, we find the mass of even unimodular
32-dimensional lattices with no roots, and the mass of odd unimodular lattices
with no roots in dimension n < 31, verifying Bacher and Venkov's enumerations
in dimensions 27 and 28. We also compute better lower bounds on the number of
inequivalent unimodular lattices in dimensions 26 to 30 than those afforded by
the Minkowski-Siegel mass constants.
  The ASCII text file table.txt (1.3 MB) at arXiv:math.NT/0012231 includes the
complete table of masses of 32-dimensional even unimodular lattices with any
given root system, and may be dowloaded using the source link.

</DOC>
<DOC>
<DOCNO> 99311 </DOCNO>
Affine surfaces with isomorphic cylinders


  We consider a cylinder over a smooth complex affine surface, i.e. the direct
product of the surface with complex line. W. Danielewski provided an example of
two nonisomorphic affine surfaces with isomorphic cylinders. Each of the
surfaces admits a $\Bbb {C}^+$ action. These actions induce fibrations of the
surfaces over the same base $X,$ such that each fiber is isomorphic to complex
line. We call $X$ a Fieseler factor. It is proved by W.Danielewski and K.-H.
Fieseler, that any two surfaces admitting fixed point-free $\Bbb {C}^+$-actions
with the same Fieseler factor, have isomorphic cylinders. We prove almost
inverse statement: if two smooth affine surfaces have isomorphic cylinders,
then either they are isomorphic or they admit $\Bbb {C}^+$-actions with
isomorphic factors. In the proof we use the invariant, defined previously by
the second author as the intersection of kernels of all locally nilpotent
derivations in the ring of regular functions of an affine variety.

</DOC>
<DOC>
<DOCNO> 9982 </DOCNO>
Stabilizing Grafted Colloids in a Polymer Melt: Favorable Enthalpic


  The interactions between spherical colloids covered with end-grafted polymers
(brushes) immersed in a polymer melt are studied theoretically. We show that
attractive enthalpic interactions between the two polymer species,
characterized by a negative Flory parameter (chi<0), can stabilize the
colloidal dispersion. The stabilizing mechanism is a result of a structural
change from a dry brush, where the melt chains do not penetrate deeply into the
brush, to a wet brush, where the free chains penetrate the brush and force the
grafted chains to extend into the melt.

</DOC>
<DOC>
<DOCNO> 11300 </DOCNO>
Magnetic Instability in a Parity Invariant 2D Fermion System


  We consider the parity invariant (2+1)-dimensional QED where the matter is
represented as a mixture of fermions with opposite spins. It is argued that the
perturbative ground state of the system is unstable with respect to the
formation of magnetized ground state. Carrying out the finite temperature
analysis we show that the magnetic instability disappears in the high
temperature regime.

</DOC>
<DOC>
<DOCNO> 119208 </DOCNO>
Optimal Masks for Low-Degree Solar Acoustic Modes


  We suggest a solution to an important problem of observational
helioseismology of the separation of lines of solar acoustic (p) modes of low
angular degree in oscillation power spectra by constructing optimal masks for
Doppler images of the Sun. Accurate measurements of oscillation frequencies of
low-degree modes are essential for the determination of the structure and
rotation of the solar core. However, these measurements for a particular mode
are often affected by leakage of other p modes arising when the Doppler images
are projected on to spherical-harmonics masks. The leakage results in
overlaping peaks corresponding to different oscillation modes in the power
spectra. In this paper we present a method for calculating optimal masks for a
given (target) mode by minimizing the signals of other modes appearing in its
vicinity. We apply this method to time series of 2 years obtained from
Michelson Doppler Imager (MDI) instrument on board SOHO space mission and
demonstrate its ability to reduce efficiently the mode leakage.

</DOC>
<DOC>
<DOCNO> 13746 </DOCNO>
The nature of the long time decay at a second order transition point


  We show that at a second order phase transition, of \phi^4 like system, a
necessary condition for streched exponential decay of the time structure factor
is obeyed. Using the ideas presented in this proof a crude estimate of the
decay of the structure factor is obtained and shown to yield stretched
exponential decay under very reasonable conditions.

</DOC>
<DOC>
<DOCNO> 68932 </DOCNO>
Cosmology of the Randall-Sundrum model after dilaton stabilization


  We provide the first complete analysis of cosmological evolution in the
Randall-Sundrum model with stabilized dilaton. We give the exact expansion law
for matter densities on the two branes with arbitrary equations of state. The
effective four-dimensional theory leads to standard cosmology at low energy.
The limit of validity of the low energy theory and possible deviations from the
ordinary expansion law in the high energy regime are finally discussed.

</DOC>
<DOC>
<DOCNO> 83213 </DOCNO>
Practical Reasoning for Very Expressive Description Logics


  Description Logics (DLs) are a family of knowledge representation formalisms
mainly characterised by constructors to build complex concepts and roles from
atomic ones. Expressive role constructors are important in many applications,
but can be computationally problematical. We present an algorithm that decides
satisfiability of the DL ALC extended with transitive and inverse roles and
functional restrictions with respect to general concept inclusion axioms and
role hierarchies; early experiments indicate that this algorithm is well-suited
for implementation. Additionally, we show that ALC extended with just
transitive and inverse roles is still in PSPACE. We investigate the limits of
decidability for this family of DLs, showing that relaxing the constraints
placed on the kinds of roles used in number restrictions leads to the
undecidability of all inference problems. Finally, we describe a number of
optimisation techniques that are crucial in obtaining implementations of the
decision procedures, which, despite the worst-case complexity of the problem,
exhibit good performance with real-life problems.

</DOC>
<DOC>
<DOCNO> 120510 </DOCNO>
The Optical Velocity of the Antlia Dwarf Galaxy


  We present the results of a VLT observing program carried out in service mode
using FORS1 on ANTU in Long Slit mode to determine the optical velocities of
nearby low surface brightness galaxies. Outlying Local Group galaxies are of
paramount importance in placing constraints the dynamics and thus on both the
age and the total mass of the Local Group. Optical velocities are also
necessary to determine if the observations of HI gas in and around these
systems are the result of gas associated with these galaxies or a chance
superposition with high velocity HI clouds or the Magellanic Stream. The data
were of sufficient signal-to-noise to obtain a reliable result in one of the
galaxies we observed - Antlia - for which we have found an optical
helio-centric radial velocity of 351 $\pm$ 15 km/s.

</DOC>
<DOC>
<DOCNO> 119304 </DOCNO>
On-Orbit Performance of the Far Ultraviolet Spectroscopic Explorer


  Launch of the Far Ultraviolet Spectroscopic Explorer (FUSE) has been followed
by an extensive period of calibration and characterization as part of the
preparation for normal satellite operations. Major tasks carried out during
this period include initial coalignment, focusing and characterization of the
four instrument channels, and a preliminary measurement of the resolution and
throughput performance of the instrument. We describe the results from this
test program, and present preliminary estimates of the on-orbit performance of
the FUSE satellite based on a combination of this data and prelaunch laboratory
measurements.

</DOC>
<DOC>
<DOCNO> 9216 </DOCNO>
Critical behavior of the S=1/2 Heisenberg ferromagnet: A Handscomb


  We investigate the critical relaxational dynamics of the S=1/2 Heisenberg
ferromagnet on a simple cubic lattice within the Handscomb prescription on
which it is a diagrammatic series expansion of the partition function that is
computed by means of a Monte Carlo procedure. Using a phenomenological
renormalization group analysis of graph quantities related to the spin
susceptibility and order parameter, we obtain precise estimates for the
critical exponents relations $\gamma / \nu = 1.98\pm 0.01 $ and $\beta /\nu =
0.512 \pm 0.002$ and for the Curie temperature $k_BT_c/J = 1.6778 \pm 0.0002$.
The critical correlation time of both energy and susceptibility is also
computed. We found that the number of Monte Carlo steps needed to generate
uncorrelated diagram configurations scales with the system's volume. We
estimate the efficiency of the Handscomb method comparing its ability in
dealing with the critical slowing down with that of other quantum and classical
Monte Carlo prescriptions.

</DOC>
<DOC>
<DOCNO> 10227 </DOCNO>
Optical conductivity of one-dimensional Mott insulators


  We calculate the optical conductivity of one-dimensional Mott insulators at
low energies using a field theory description. The square root singularity at
the optical gap, characteristic of band insulators, is generally absent and
appears only at the Luther-Emery point. We also show that only few particle
processes contribute significantly to the optical conductivity over a wide
range of frequencies and that the bare perturbative regime is recovered only at
very large energies. We discuss possible applications of our results to quasi
one-dimensional organic conductors.

</DOC>
<DOC>
<DOCNO> 8681 </DOCNO>
Understanding high-Tc cuprates based on the phase string theory of doped


  We present a self-consistent RVB theory which unifies the metallic
(superconducting) phase with the half-filling antiferromagnetic (AF) phase. Two
crucial factors in this theory include the RVB condensation which controls
short-range AF spin correlations and the phase string effect introduced by hole
hopping as a key doping effect. We discuss both the uniform and non-uniform
mean-field solutions and show the unique features of the characteristic spin
energy scale, superconducting transition temperature, and the phase diagram,
which are all consistent with the experimental measurements of high-$T_c$
cuprates.

</DOC>
<DOC>
<DOCNO> 67962 </DOCNO>
Attractive and Repulsive Gravity


  We discuss the circumstances under which gravity might be repulsive rather
than attractive. In particular we show why our standard solar system distance
scale gravitational intuition need not be a reliable guide to the behavior of
gravitational phenomena on altogether larger distance scales such as
cosmological, and argue that in fact gravity actually gets to act repulsively
on such distance scales. With such repulsion a variety of current cosmological
problems (the flatness, horizon, dark matter, universe age, cosmic acceleration
and cosmological constant problems) are then all naturally resolved.

</DOC>
<DOC>
<DOCNO> 119054 </DOCNO>
A new component of the Galaxy as the origin of the LMC microlensing


  We suggest a new component of the Milky Way that can account for both the
optical depth and event durations implied by microlensing searches targeting
the Large Magellanic Cloud. This component, which represents less than 4% of
the total dark matter halo mass, consists of mainly old white dwarf stars in a
distribution that extends beyond the disk of the galaxy, but lies well within
the dark matter halo. It is consistent with recent evidence for a significant
population of white dwarfs detected in proper motion studies of the Hubble Deep
Field that cannot be accounted for by stars in the disk or spheroid. Further,
it evades all of the current observational constraints that restrict a halo
population of white dwarfs.

</DOC>
<DOC>
<DOCNO> 118460 </DOCNO>
Optical studies of the X-ray transient XTE J2123-058 -I. Photometry


  We present optical photometry of the X-ray transient XTE J2123-058, obtained
in July-October 1998. The light curves are strongly modulated on the 5.95hrs
orbital period, and exhibit dramatic changes in amplitude and form during the
decline. We used synthetic models which include the effect of partial eclipses
and X-ray heating effects, to estimate the system parameters, and we constrain
the binary inclination to be i=73+-4 degrees. The model is successful in
reproducing the light curves at different stages of the decay by requiring the
accretion disc to become smaller and thinner by 30% as the system fades by 1.7
mags in the optical. From Aug 26 the system reaches quiescence with a mean
magnitude of R=21.7+-0.1 and our data are consistent with the optical
variability being dominated by the companion's ellipsoidal modulation.

</DOC>
<DOC>
<DOCNO> 119841 </DOCNO>
Multiperiodicity in semiregular variables II. Systematic amplitude


  We present a detailed lightcurve analysis for a sample of bright semiregular
variables based on long-term (70--90 years) visual magnitude estimates carried
out by amateur astronomers. Fundamental changes of the physical state
(amplitude and/or frequency modulations, mode change and switching) are studied
with the conventional Fourier- and wavelet analysis.
  The light curve of the carbon Mira Y Per showing a gradual amplitude decrease
has been re-analysed after collecting and adding current data to earlier ones.
The time scales of the sudden change and convection are compared and their
similar order of magnitude is interpreted to be a possible hint for strong
coupling between pulsation and convection. The periods of the biperiodic
low-amplitude light curve and their ratios suggest a pulsation in the first and
third overtone modes. An alternative explanation of the observed behaviour
could be a period halving due to the presence of weak chaos.
  Beside two examples of repetitive mode changes (AF Cyg and W Cyg) we report
three stars with significant amplitude modulations (RY Leo, RX UMa and RY UMa).
A simple geometric model of a rotationally induced amplitude modulation in RY
UMa is outlined assuming low-order nonradial oscillation, while the observed
behaviour of RX UMa and RY Leo is explained as a beating of two closely
separated modes of pulsation. This phenomenon is detected unambiguously in V
CVn, too. The period ratios found in these stars (1.03-1.10) suggest either
high-order overtone or radial+non-radial oscillation.

</DOC>
<DOC>
<DOCNO> 10194 </DOCNO>
Exact Solution of the Three-color Problem on a Random Lattice


  We present the exact solution of the Baxter's three-color problem on a random
planar graph, using the random-matrix formulation of the problem, given by B.
Eynard and C. Kristjansen. We find that the number of three-coloring of an
infinite random graph is 0.9843 per vertex.

</DOC>
<DOC>
<DOCNO> 9417 </DOCNO>
Influence of a polaron dispersion and excitonic effect on a


  It has been shown, that a magnetopolaron discrete energy spectrum is realized
in the optical experiments where exciting light is directed perpendicularly to
a quantum well (QW) plane. The phonon dispersion as well as Coulomb attraction
can only shift the magnetopolaron discrete energy levels and broad some of
them.

</DOC>
<DOC>
<DOCNO> 117560 </DOCNO>
Probing the Neutron Star Interior with Glitches


  With the aim of constraining the structural properties of neutron stars and
the equation of state of dense matter, we study sudden spin-ups, glitches,
occurring in the Vela pulsar and in six other pulsars. We present evidence that
glitches represent a self-regulating instability for which the star prepares
over a waiting time. The angular momentum requirements of glitches in Vela
indicate that at least 1.4% of the star's moment of inertia drives these
events. If glitches originate in the liquid of the inner crust, Vela's
`radiation radius' $R_\infty$ must exceed ~12 km for a mass of 1.4 solar
masses. The isolated neutron star RX J18563-3754 is a promising candidate for a
definitive radius measurement, and offers to further our understanding of dense
matter and the origin of glitches.

</DOC>
<DOC>
<DOCNO> 69584 </DOCNO>
Brane world: disappearing massive matter


  In a brane (domain wall) scenario with an infinite extra dimension and
localized gravity, bulk fermions and scalars often have bound states with zero
4-dimensional mass. In this way massless matter residing on the brane may be
obtained. We consider what happens when one tries to introduce small, but
non-vanishing mass to these matter fields. We find that the discrete zero modes
turn into quasi-localized states with finite 4-dimensional mass and finite
width. The latter is due to tunneling of massive matter into extra dimension.
We argue that this phenomenon is generic to fields that can have bulk modes. We
also point out that in theories meant to describe massive scalars, the
4-dimensional scalar potential has, in fact, power-law behavior at large
distances.

</DOC>
<DOC>
<DOCNO> 150822 </DOCNO>
Let's Baxterise


  We recall the concept of Baxterisation of an R-matrix, or of a monodromy
matrix, which corresponds to build, from one point in the $ R$-matrix parameter
space, the algebraic variety where the spectral parameter(s) live. We show that
the Baxterisation, which amounts to studying the iteration of a birational
transformation, is a ``win-win'' strategy: it enables to discard efficiently
the non-integrable situations, focusing directly on the two interesting cases
where the algebraic varieties are of the so-called ``general type'' (finite
order iteration) or are Abelian varieties (infinite order iteration). We
emphasize the heuristic example of the sixteen vertex model and provide a
complete description of the finite order iterations situations for the Baxter
model. We show that the Baxterisation procedure can be introduced in much
larger frameworks where the existence of some underlying Yang-Baxter structure
is not used: we Baxterise L-operators, local quantum Lax matrices, and quantum
Hamiltonians.

</DOC>
<DOC>
<DOCNO> 123140 </DOCNO>
The determination of mass of stellar disks of galaxies from the


  Different ways of the determination of masses of galactic disks, based on the
kinematic data, are briefly discussed. The analysis of the rotation curves
which reach maximum inside of a disk, and N-body modeling, reproducing the
rotation curves and stellar velocity dispersion of real galaxies, enable to
conclude that the mass of a disk is usually significantly less than the total
mass of spherical components (bulge + dark halo) inside of optical borders of a
galaxy, although the exceptions also exist.

</DOC>
<DOC>
<DOCNO> 12884 </DOCNO>
Upper critical dimension, dynamic exponent and scaling functions in the


  We study the mode-coupling approximation for the KPZ equation in the strong
coupling regime. By constructing an ansatz consistent with the asymptotic forms
of the correlation and response functions we determine the upper critical
dimension d_c=4, and the expansion z=2-(d-4)/4+O((4-d)^2) around d_c. We find
the exact z=3/2 value in d=1, and estimate the values 1.62, 1.78 for z, in
d=2,3. The result d_c=4 and the expansion around d_c are very robust and can be
derived just from a mild assumption on the relative scale on which the response
and correlation functions vary as z approaches 2.

</DOC>
<DOC>
<DOCNO> 39810 </DOCNO>
Search for CP violation in B+- -> J/psi K+- and B+- -> psi(2S) K+-


  We present a search for direct CP violation in B+- -> J/psi K+- and B+- ->
psi(2S) K+- decays. In a sample of 9.7 million B meson pairs collected with the
CLEO detector, we have fully reconstructed 534 B+- -> J/psi K+- and 120 B+- ->
psi(2S) K+- decays with very low background. We have measured the CP-violating
charge asymmetry to be (+1.8+-4.3[stat]+-0.4[syst])% for B+- -> J/psi K+- and
(+2.0+-9.1[stat]+-1.0[syst])% for B+- -> psi(2S) K+-.

</DOC>
<DOC>
<DOCNO> 12049 </DOCNO>
The effect of a topological gauge field on Bose-Einstein condensation


  We show that Bose-Einstein condensation of charged scalar fields interacting
with a topological gauge field at finite temperature is inhibited except for
special values of the topological field. We also show that fermions interacting
with this topological gauge field can condense for some values of the gauge
field.

</DOC>
<DOC>
<DOCNO> 121545 </DOCNO>
Orbital solution for the MACHO*05:34:41.3 -69:31:39 O3 If*+O6:V


  An orbital solution to the MACHO*05:34:41.3 -69:31:39 eclipsing binary system
is presented, based on the published light curve and spectral data obtained
with the 2.15-m telescope at CASLEO. Based on these spectroscopic observations,
this system's binary components were classified as O3 If* and O6:V
respectively. The radial velocity data alongwith the published light curve were
analysed with the Wilson-Devinney code to derive the following masses and radii
for the components of this system: M1 = 41 +- 1.2, R1 = 9.6 +- 0.02, M2 = 27 +-
1.2 and R2 = 8.0 +- 0.05, in solar units. The solution shows that the system is
in over-contact as one would expect from the derived masses and the very short
orbital period (~1.4 days).

</DOC>
<DOC>
<DOCNO> 118801 </DOCNO>
Limits on magnetic field strength of the extended nebula of PSR B1706-44


  The detection of unpulsed TeV emission from PSR B1706-44 raised the question
if this VHE emission results from inverse Compton scattering of multi-TeV
electrons on the CMBR and other soft photon fields. This hints at the existence
of an unseen synchrotron nebula, which is larger than the observed 1 arcminute
compact X-ray nebula. In a search for synchrotron counterpart of the TeV
nebula, we have taken V-band CCD images of the region around the PSR B1706-44
pulsar position. By rejecting all point source contributions down to the
diffuse sky limit, we were able to search for such extended plerionic
synchrotron emission on scale sizes limited by the angular resolution of the
CANGAROO imaging TeV observations. By combining the V-band flux limits with the
observed TeV flux, we were able to obtain upper limits for the magnetic field
strength as a function of the radius of the assumed TeV nebula. Assuming that
the 2 arcminute radio plerion also defines the size of the TeV nebula, we
constrain the steady state particle spectral index to the values between 4 and
5.5, with a field strength limit of about 3x10^-6 G. This compares with an
index of 3.6+/-0.6 inside the 1 arcminute compact X-ray nebula.

</DOC>
<DOC>
<DOCNO> 102016 </DOCNO>
Wick Type Symbol and Deformed Algebra of Exterior Forms


  The covariant descripion is constructed for the Wick-type symbols on
symplectic manifolds by means of the Fedosov procedure. The geometry of the
manifolds admitting this symbol is explored. The superextended version of the
Wick-type star-product is introduced and a possible application of the
construction to the noncommutative field theory is discussed.

</DOC>
<DOC>
<DOCNO> 69175 </DOCNO>
DSE Hadron Phenomenology


  A perspective on the contemporary use of Dyson-Schwinger equations, focusing
on some recent phenomenological applications: a description and unification of
light-meson observables using a one-parameter model of the effective
quark-quark interaction, and studies of leptonic and nonleptonic nucleon form
factors.

</DOC>
<DOC>
<DOCNO> 102269 </DOCNO>
Periodic orbits of Hamiltonian flows near symplectic extrema


  For Hamiltonian flows we establish the existence of periodic orbits on a
sequence of level sets approaching a Bott-nondegenerate symplectic extremum of
the Hamiltonian. As a consequence, we show that a charge on a compact manifold
with a nondegenerate (i.e. symplectic) magnetic field has periodic orbits on a
sequence of energy levels converging to zero.

</DOC>
<DOC>
<DOCNO> 13697 </DOCNO>
Effects of a parallel magnetic field on the novel metallic behavior in


  Magnetoconductance (MC) in a parallel magnetic field B has been measured in a
two-dimensional electron system in Si, in the regime where the conductivity
decreases as \sigma (n_s,T,B=0)=\sigma (n_s,T=0) + A(n_s)T^2 (n_s -- carrier
density) to a non-zero value as temperature T->0. Very near the B=0
metal-insulator transition, there is a large initial drop in \sigma with
increasing B, followed by a much weaker \sigma (B). At higher n_s, the initial
drop of MC is less pronounced.

</DOC>
<DOC>
<DOCNO> 178618 </DOCNO>
Quantum Monte Carlo Calculations of Pion Scattering from Li


  We show that the neutron and proton transition densities predicted by recent
quantum Monte Carlo calculations for A=6,7 nuclei are consistent with pion
scattering from 6Li and 7Li at energies near the Delta resonance. This has
provided a microscopic understanding of the enhancement factors for quadrople
excitations, which were needed to describe pion inelastic scattering within the
nuclear shell model of Cohen and Kurath.

</DOC>
<DOC>
<DOCNO> 67738 </DOCNO>
Neutrino Conversions in Active Galactic Nuclei


  I discuss the possibility of production of high energy cosmic neutrinos (E
\geq 10^{6} GeV) in cores of active galactic nuclei and study some of the
effects of neutrino mixing on their subsequent propagation. I also discuss the
prospects for observations of these high energy cosmic neutrinos in new km^{2}
surface area underwater/ice neutrino telescopes.

</DOC>
<DOC>
<DOCNO> 121560 </DOCNO>
Evolution of the X-ray luminosity and metallicity of starburst blown


  We calculate the time-dependent metal production expected from starbursts and
use them as boundary conditions in our 2D simulations of evolving superbubbles.
We assume that the produced metals (oxygen and iron) thoroughly mix with the
ejected stellar envelopes, and/or with the matter thermally evaporated from the
superbubble cold outer shell. The metal production process determines the
time-dependent metallicity in hot superbubble interiors, and leads to values of
Z greater or equal than solar, when oxygen is used as tracer, and under-solar
when the metallicity is measured with respect to iron. In either case, the
enhanced metallicity boosts the X-ray emissivity of superbubbles, bringing
theory and observations closer together.

</DOC>
<DOC>
<DOCNO> 9043 </DOCNO>
Resonant tunneling in GaAs/AlGaAs triple-barrier structures under


  The effect of an in-plane magnetic field on resonant tunneling in a symmetric
GaAs/AlYGa1-YAs triple-barrier resonant tunneling TBRT structure is presented.
The splitting of the resonant lines (and hence the coupling energy vs. magnetic
induction) for the ground and the first excited resonant doublet shifts up in
energy by increasing the magnetic induction. Each of branches in the resonant
dispersion relations shows a parabolic behavior with the location of the
cyclotron orbit center. It is expected that, at very high fields, the
interaction with confined phonons be enhanced, due to phonon coupling between
electron states in the ground quasibound doublet.

</DOC>
<DOC>
<DOCNO> 12205 </DOCNO>
Point contact tunneling in the fractional quantum Hall effect: an exact


  In the weak backscattering limit, point contact tunneling between quantum
Hall edges is well described by a Poissonian process where Laughlin
quasiparticles tunnel independently, leading to the unambiguous measurement of
their fractional charges. In the strong backscattering limit, the tunneling is
well described by a Poissonian process again, but this time involving real
electrons. In between, interactions create essential correlations, which we
untangle exactly in this Letter. Our main result is an exact closed form
expression for the probability distribution of the charge $N(t)$ that tunnels
in the time interval $t$. Formally, this distribution corresponds to a sum of
independent Poisson processes carrying charge $\nu e$, $2\nu e$, etc., or,
after resummation, processes carrying charge $e$, $2e$, etc. In the course of
the proof, we compare the integrable and Keldysh approaches, and find, as a
result of spectacular cancellations between perturbative integrals, the
expected agreement.

</DOC>
<DOC>
<DOCNO> 71125 </DOCNO>
Bottomonia Hadroproduction


  We analyze Tevatron data of bottomonium hadroproduction in the framework of
the colour-octet model (COM) implemented in the event generator PYTHIA using
CTEQ4L PDF taking into account initial-state radiation of gluons and
Altarelli-Parisi evolution of final-state gluons. We obtain new values for the
colour-octet matrix elements relevant to this production process for the
Upsilon(nS) family (n=1,2,3), finding that the ^1S_0^{(8)}+^3P_J^{(8)}
contributions are not needed in the fit. We show the different contributions to
Upsilon(1S) production at Tevatron for p_T>8 GeV, comparing them with CDF data.
Finally we extrapolate to LHC energies to predict Upsilon(nS) production rates.

</DOC>
<DOC>
<DOCNO> 99299 </DOCNO>
Left-modular elements


  Left-modularity is a concept that generalizes modularity in lattice theory.
In this paper, we give a characterization of left-modular elements and derive
two formulae for the characteristic polynomial of a lattice with such an
element, one of which generalizes Stanley's Partial Factorization Theorem for a
geometric lattice with a modular element. Both formulae provide us with
inductive proofs of Blass and Sagan's Total Factorization Theorem for LL
lattices. The characteristic polynomials and Mobius functions of non-crossing
partition lattices and shuffle posets are computed as examples.

</DOC>
<DOC>
<DOCNO> 122485 </DOCNO>
Chandra imaging of the X-ray core of Abell 1795


  We report the discovery of a 40 arcsec long X-ray filament in the core of the
cluster of galaxies A1795. The feature coincides with an Halpha+NII filament
found by Cowie et al in the early 1980s and resolved into at least 2 U-band
filaments by McNamara et al in the mid 1990s. The (emission-weighted)
temperature of the X-ray emitting gas along the filament is 2.5-3 keV, as
revealed by X-ray colour ratios. The deprojected temperature will be less. A
detailed temperature map of the core of the cluster presented. The cD galaxy at
the head of the filament is probably moving through or oscillating in the
cluster core. The radiative cooling time of the X-ray emitting gas in the
filament is about 3x10^8 yr which is similar to the age of the filament
obtained from its length and velocity. This suggests that the filament is
produced by cooling of the gas from the intracluster medium. The filament, much
of which is well separated from the body of the cD galaxy and its radio source,
is potentially of great importance in helping to understand the energy and
ionization source of the optical nebulosity common in cooling flows.

</DOC>
<DOC>
<DOCNO> 72276 </DOCNO>
CP Violation in Seesaw Model


  We study the structure of CP violating phases in the seesaw model. We find
that the $3\times 6$ MNS matrix contains six independent phases, three of which
are identified as a Dirac phase and two Majorana phases in the light neutrino
sector while the remaining three arise from the mixing of the light neutrinos
and heavy neutrinos. We show how to determine these phases from physical
observables.

</DOC>
<DOC>
<DOCNO> 123175 </DOCNO>
The 2dF QSO Redshift Survey - II. Structure and evolution at high


  We present a clustering analysis of QSOs over the redshift range z=0.3-2.9.
We use a sample of 10558 QSOs taken from the preliminary catalogue of the 2dF
QSO Redshift Survey (2QZ). The two-point redshift-space correlation function of
QSOs is shown to follow a power law on scales s~1-35h-1Mpc. Fitting a power law
to QSO clustering averaged over the redshift interval 0.3<z<2.9 we find
s_0=3.99+0.28-0.34h-1Mpc and gamma=1.58+0.10-0.09 for an Einstein-de Sitter
cosmology (EdS). With Omega_0=0.3 and lambda_0=0.7 the power law extends to
s~60h-1Mpc with a best fit of s_0=5.69+0.42-0.50h-1Mpc and
gamma=1.56+0.10-0.09. These values, measured at a mean redshift of z=1.49, are
comparable to the clustering of local optically selected galaxies. We measure
the evolution of QSO clustering as a function of redshift. For an EdS cosmology
there is no evolution in comoving coordinates over the redshift range of the
2QZ. For Omega_0=0.3 and lambda_0=0.7 QSO clustering shows a marginal increase
at high redshift. Although the clustering of QSOs is measured on large scales
where linear theory should apply, the evolution of QSO clustering does not
follow the linear theory predictions for growth via gravitational instability
(rejected at the >99 per cent confidence level). A redshift dependent bias is
required to reconcile QSO clustering observations with theory. A simple biasing
model, in which QSOs have cosmologically long lifetimes (or alternatively form
in peaks above a constant threshold in the density field) is acceptable in an
EdS cosmology, but is only marginally acceptable if Omega_0=0.3 and
lambda_0=0.7. Biasing models which assume QSOs form over a range in redshift,
based on the Press-Schechter formalism are approximately consistent with QSO
clustering evolution (abridged).

</DOC>
<DOC>
<DOCNO> 102115 </DOCNO>
Non-Locality of Equivariant Star Products on $T*(RP^n)$


  Lecomte and Ovsienko constructed $SL_{n+1}(R)$-equivariant quantization maps
$Q_\lambda$ for symbols of differential operators on $\lambda$-densities on
$\RP^n$.
  We derive some formulas for the associated graded equivariant star products
$star_\lambda$ on the symbol algebra $Pol(T*\RP^n)$. These give some measure of
the failure of locality.
  Our main result expresses (for $n$ odd) the coefficients $C_p$ of
$star_\lambda$ when $\lambda=\half$ in terms of some new
$SL_{n+1}(C)$-invariant algebraic bidifferential operators $Z_p$ on $T*\CP^n$
and the operators $(E+\frac{n}{2}\pm s)^{-1}$ where $E$ is the fiberwise Euler
vector field and $s\in\{1,2,...,[\frac{p}{2}]\}$.

</DOC>
<DOC>
<DOCNO> 12782 </DOCNO>
Superconductivity in a Dilute Two Dimensional Electron System


  We develop a finite temperature mean field theory in the path integral
picture for an extremely dilute system of interacting Fermions in a plane. In
the limit of short ranged interactions, the system is shown to undergo a phase
transition to a superconducting regime. Unlike the well known BCS transition
for metals, this phase transition is found to be very sensitive to the two
dimensional nature of the problem. A quantitative estimate of this sensitivity
is carried out by repeating the analysis at non-zero thickness. The validity of
the mean field results are also proved using renormalization group techniques.

</DOC>
<DOC>
<DOCNO> 99349 </DOCNO>
Cohomologies of Affine Jacobi Varieties and Integrable Systems


  We study the affine ring of the affine Jacobi variety of a hyper-elliptic
curve. The matrix construction of the affine hyper-elliptic Jacobi varieties
due to Mumford is used to calculate the character of the affine ring. By
decomposing the character we make several conjectures on the cohomology groups
of the affine hyper-elliptic Jacobi varieties. In the integrable system
described by the family of these affine hyper-elliptic Jacobi varieties, the
affine ring is closely related to the algebra of functions on the phase space,
classical observables. We show that the affine ring is generated by the highest
cohomology group over the action of the invariant vector fields on the Jacobi
variety.

</DOC>
<DOC>
<DOCNO> 151612 </DOCNO>
New Superconformal Field Theories in Four Dimensions and N=1 Duality


  Recently, developments in the understanding of low-energy N=1 supersymmetric
gauge theory have revealed two important phenomena: the appearance of new
four-dimensional superconformal field theories and a non-Abelian generalization
of electric-magnetic duality at the IR fixed point. This report is a
pedagogical introduction to these phenomena. After presenting some necessary
background material, a detailed introduction to the low-energy non-perturbative
dynamics of N=1 supersymmetric $SU(N_c)$ QCD is given. The emergence of new
four-dimensional superconformal field theories and non-Abelian duality is
explained. New non-perturbative phenomena in supersymmetric $SO(N_c)$ and
$Sp(N_c=2n_c)$ gauge theories, such as the two inequivalent branches, oblique
confinement and electric-magnetic-dyonic triality, are presented. Finally, some
new features of these four-dimensional superconformal field theories are
exhibited: the universal operator product expansion, evidence for a possible
$c$-theorem in four dimensions and the critical behaviour of anomalous
currents. The concluding remarks contain a brief history of electric-magnetic
duality and a discussion on the possible applications of duality to ordinary
QCD.

</DOC>
<DOC>
<DOCNO> 9321 </DOCNO>
The Dynamical Cluster Approximation: A New Technique for Simulations of


  We present the algorithmic details of the dynamical cluster approximation
(DCA) algorithm. The DCA is a fully-causal approach which systematically
restores non-local correlations to the dynamical mean field approximation
(DMFA). The DCA is in the thermodynamic limit and becomes exact for an infinite
cluster size, while reducing to the DMFA for a cluster size of unity. Using the
one-dimensional Hubbard Model as a non-trivial test of the method, we
systematically compare the results of a quantum Monte Carlo (QMC) based DCA
with those obtained by finite-size QMC simulations (FSS). We find that the
single-particle Green function and the self-energy of the DCA and FSS approach
the same limit as the system size is increased, but from complimentary
directions. The utility of the DCA in addressing problems that have not been
resolved by FSS is demonstrated.

</DOC>
<DOC>
<DOCNO> 178494 </DOCNO>
Color Dynamics On Phase Space


  We describe the properties of quark matter at zero temperature and finite
baryon densities within microscopic Vlasov/molecular dynamics approaches. We
use an inter-quark Richardson's potential consistent with the indications of
Lattice QCD calculations. The color degrees of freedom are explicitly taken
into account.
 We explicitly demonstrate that the Vlasov approach alone is insufficient in
the hadronization region. In order to overcome this problem we prepare the
initial condition for many events using molecular dynamics with frictional
cooling and a Thomas-Fermi approximation to the Fermi motion.
  These events are averaged and propagated in time using the Vlasov approach.
 We find some evidence for a second order phase transition from nuclear to
quark matter at high baryon densities. An order parameter suitable to describe
the phase transition is discussed. At low densities the quark condensate into
approximately color white clusters (nucleon).

</DOC>
<DOC>
<DOCNO> 85400 </DOCNO>
Hamiltonians for a general dilaton gravity theory on a spacetime with a


  A generalization of two recently proposed general relativity Hamiltonians, to
the case of a general (d+1)-dimensional dilaton gravity theory in a manifold
with a timelike or spacelike outer boundary, is presented.

</DOC>
<DOC>
<DOCNO> 169799 </DOCNO>
Causality, delocalization and positivity of energy


  In a series of interesting papers G. C. Hegerfeldt has shown that quantum
systems with positive energy initially localized in a finite region,
immediately develop infinite tails. In our paper Hegerfeldt's theorem is
analysed using quantum and classical wave packets. We show that Hegerfeldt's
conclusion remains valid in classical physics. No violation of Einstein's
causality is ever involved. Using only positive frequencies, complex wave
packets are constructed which at $t = 0$ are real and finitely localized and
which, furthemore, are superpositions of two nonlocal wave packets. The
nonlocality is initially cancelled by destructive interference. However this
cancellation becomes incomplete at arbitrary times immediately afterwards. In
agreement with relativity the two nonlocal wave packets move with the velocity
of light, in opposite directions.

</DOC>
<DOC>
<DOCNO> 152133 </DOCNO>
Cosmology on a Brane in Minkowski Bulk


  We discuss the cosmology of a 3-brane embedded in a 5D bulk space-time with a
cosmological constant when an intrinsic curvature Ricci scalar is included in
the brane action. After deriving the `brane-Friedmann' equations for a Z_2
symmetrical metric, we focus on the case of a Minkowski bulk. We show that
there exist two classes of solutions, close to the usual
Friedmann-Lemaitre-Robertson-Walker cosmology for small enough Hubble radii.
When the Hubble radius gets larger one either has a transition to a fully 5D
regime or to a self-inflationary solution which produces a late accelerated
expansion. We also compare our results with a perturbative approach and
eventually discuss the embedding of the brane into the Minkowski space-time.
This latter part of our discussion also applies when no intrinsic curvature
term is included.

</DOC>
<DOC>
<DOCNO> 80609 </DOCNO>
Anomaly Cancellation Condition in Lattice Gauge Theory


  We study the gauge anomaly ${\cal A}$ defined on a 4-dimensional infinite
lattice while keeping the lattice spacing finite. We assume that (I) ${\cal A}$
depends smoothly and locally on the gauge potential, (II) ${\cal A}$ reproduces
the gauge anomaly in the continuum theory in the classical continuum limit, and
(III) U(1) gauge anomalies have a topological property. It is then shown that
the gauge anomaly ${\cal A}$ can always be removed by local counterterms to all
orders in powers of the gauge potential, leaving possible breakings
proportional to the anomaly in the continuum theory. This follows from an
analysis of nontrivial local solutions to the Wess-Zumino consistency condition
in lattice gauge theory. Our result is applicable to the lattice chiral gauge
theory based on the Ginsparg-Wilson Dirac operator, when the gauge field is
sufficiently weak $\|U(n,\mu)-1\|<\epsilon'$, where $U(n,\mu)$ is the link
variable and $\epsilon'$ a certain small positive constant.

</DOC>
<DOC>
<DOCNO> 118287 </DOCNO>
The porous atmosphere of eta Carinae


  We analyze the wind generated by the great 20 year long super-Eddington
outburst of eta-Carinae. We show that using classical stellar atmospheres and
winds theory, it is impossible to construct a consistent wind model in which a
sufficiently small amount of mass, like the one observed, is shed. One expects
the super-Eddington luminosity to drive a thick wind with a mass loss rate
substantially higher than the observed one. The easiest way to resolve the
inconsistency is if we alleviate the implicit notion that atmospheres are
homogeneous. An inhomogeneous atmosphere, or "porous", allows more radiation to
escape while exerting a smaller average force. Consequently, such an atmosphere
yields a considerably lower mass loss rate for the same total luminosity.
Moreover, all the applications of the Eddington Luminosity as a strict
luminosity limit should be revised, or at least reanalyzed carefully.

</DOC>
<DOC>
<DOCNO> 11670 </DOCNO>
Quasi-one and two-dimensional transitions of gases adsorbed on nanotube


  Grand canonical Monte Carlo simulations have been performed to determine the
adsorption behavior of Ar and Kr atoms on the exterior surface of a rope
(bundle) consisting of many carbon nanotubes. The computed adsorption isotherms
reveal phase transitions associated with the successive creation of quasi-one
dimensional lines of atoms near and parallel to the intersection of two
adjacent nanotubes.

</DOC>
<DOC>
<DOCNO> 174487 </DOCNO>
New Limit on the D Coefficient in Polarized Neutron Decay


  We describe an experiment that has set new limits on the time reversal
invariance violating D coefficient in neutron beta-decay. The emiT experiment
measured the angular correlation J . p_e x p_p using an octagonal symmetry that
optimizes electron-proton coincidence rates. The result is
D=[-0.6+/-1.2(stat)+/-0.5(syst)]x10^(-3). This improves constraints on the
phase of g_A/g_V and limits contributions to T violation due to leptoquarks.
This paper presents details of the experiment, data analysis, and the
investigation of systematic effects.

</DOC>
<DOC>
<DOCNO> 178627 </DOCNO>
Charge Symmetry Violation in $pn\to d \pi^0$ as a Test of Chiral


  Chiral effective field theory predicts a specific charge symmetry violating
amplitude for pion production. This term is shown to provide the dominant
contribution to the forward-backward asymmetry in the angular distribution for
the reaction $pn\to d\pi^0$, for reasonable values of the mass difference
between down and up quarks, $\delta m_N$. Using a value $\delta m_N\approx$ 3
MeV leads to a prediction of a 10 standard deviation effect for a TRIUMF
experiment.

</DOC>
<DOC>
<DOCNO> 99469 </DOCNO>
Bosonized supersymmetric quantum mechanics and supersymmetry of


  We review the construction of minimally bosonized supersymmetric quantum
mechanics and its relation to hidden supersymmetries in pure parabosonic
(parafermionic) systems.

</DOC>
<DOC>
<DOCNO> 118572 </DOCNO>
Structure of the Large Magellanic Cloud from 2MASS


  We derive structural parameters and evidence for extended tidal debris from
star count and preliminary standard candle analyses of the Large Magellanic
Cloud based on Two Micron All Sky Survey (2MASS) data. The full-sky coverage
and low extinction in K_s presents an ideal sample for structural analysis of
the LMC.
  The star count surface densities and deprojected inclination for both young
and older populations are consistent with previous work. We use the full areal
coverage and large LMC diameter to Galactrocentric distance ratio to infer the
same value for the disk inclination based on perspective.
  A standard candle analysis based on a sample of carbon long-period variables
(LPV) in a narrow color range, 1.6<J-K_s<1.7 allows us to probe the
three-dimensional structure of the LMC along the line of sight. The intrinsic
brightness distribution of carbon LPVs in selected fields implies that
$\sigma_M\simlt 0.2^m$ for this color cut. The sample provides a {\it direct}
determination of the LMC disk inclination: $42.3^\circ\pm 7.2^\circ$.
  Distinct features in the photometric distribution suggest several distinct
populations. We interpret this as the presence of an extended stellar component
of the LMC, which may be as thick as 14 kpc, and intervening tidal debris at
roughly 15 kpc from the LMC.

</DOC>
<DOC>
<DOCNO> 69813 </DOCNO>
Effects of non-factorizable metric on neutrino oscillation inside


  In this paper we construct the interaction potential between the dense
supernova core and neutrinos due to the exchange of light radions in the
Randall-Sundrum scenario. We then show that the radion exchange potential
affects the neutrino oscillation phenomenology inside the supernova
significantly if the radion mass is less than around 1 GeV. In order that the
Bethe-Wilson mechanism for heating the envelope and r-process neucleosynthesis
be operative, the radion mass must be greater than 1 GeV. Bounds on the radion
mass of the same order of magnitude can also be derived from TASSO and CLEO
data on B decays.

</DOC>
<DOC>
<DOCNO> 10822 </DOCNO>
Theory of valence transitions in ytterbium-based compounds


  The anomalous behavior of YbInCu4 and similar compounds is modeled by the
exact solution of the spin one-half Falicov-Kimball model in infinite
dimensions. The valence-fluctuating transition is related to a metal-insulator
transition caused by the Falicov-Kimball interaction, and triggered by the
change in the f-occupancy.

</DOC>
<DOC>
<DOCNO> 151504 </DOCNO>
S-Duality, Noncritical Open String and Noncommutative Gauge Theory


  We examine several aspects of S-duality of four-dimensional noncommutative
gauge theory. By making duality transformation explicit, we find that S-dual of
noncommutative gauge theory is defined in terms of dual noncommutative
deformation. In `magnetic' noncommutative U(1) gauge theory, we show that, in
addition to gauge bosons, open D-strings constitute important low-energy
excitations: noncritical open D-strings. Upon S-duality, they are mapped to
noncritical open F-strings. We propose that, in dual `electric' noncommutative
U(1) gauge theory, the latters are identified with gauge-invariant, open Wilson
lines. We argue that the open Wilson lines are chiral due to underlying parity
noninvariance and obey spacetime uncertainty relation. We finally argue that,
at high energy-momentum limit, the `electric' noncommutative gauge theory
describes correctly dynamics of delocalized multiple F-strings.

</DOC>
<DOC>
<DOCNO> 69431 </DOCNO>
Deep-inelastic structure functions: Reconstruction from Mellin moments


  We summarize the method of calculating Mellin moments of deep-inelastic
structure functions in perturbative QCD. We briefly discuss all steps to a
complete analytical reconstruction of the perturbative corrrections in x-space.

</DOC>
<DOC>
<DOCNO> 70545 </DOCNO>
Implications of Recent Measurements of Nonleptonic Charmless B Decays


  Implications of recent measurements of hadronic charmless B decays are
discussed.

</DOC>
<DOC>
<DOCNO> 70968 </DOCNO>
Perturbative Pions in Deuteron Compton Scattering and Three Body Physics


  Elastic deuteron Compton scattering and the quartet S wave of nd scattering
are investigated in the effective field theory of nuclear physics with
perturbative pions. Convergence and aggreement with experiment are good.

</DOC>
<DOC>
<DOCNO> 122827 </DOCNO>
Title: The obscured mid-infrared continuum of NGC 4418: a dust- and


  We report the detection of absorption features in the 6-8 micron region
superimposed on a featureless mid-infrared continuum in NGC 4418. For several
of these features this is the first detection in an external galaxy. We compare
the absorption spectrum of NGC 4418 to that of embedded massive protostars and
the Galactic centre, and attribute the absorption features to ice grains and to
hydrogenated amorphous carbon grains. From the depth of the ice features, the
powerful central source responsible for the mid-infrared emission must be
deeply enshrouded. Since this emission is warm and originates in a compact
region, an AGN must be hiding in the nucleus of NGC 4418.

</DOC>
<DOC>
<DOCNO> 40444 </DOCNO>
Study of $B\to \psi (2S)K$ and $B\to \psi (2S)K^{*}$(892) Decays


  Color-suppressed decays of $B$ mesons to final states with $\psi(2S)$ mesons
have been observed with the CLEO detector. The branching fractions for the
decays $B^+ \to \psi(2S) K^+$, $B^+ \to \psi(2S) K^*(892)^+$, $B^0 \to \psi(2S)
K^0$, and $B^0 \to \psi(2S) K^*(892)^0$ are measured to be (7.8 +- 0.7 +- 0.9)
10^{-4}$, (9.2 +- 1.9 +- 1.2) 10^{-4}$, (5.0 +- 1.1 +- 0.6) 10^{-4}$, and (7.6
+- 1.1 +- 1.0) 10^{-4}$, respectively, where the first uncertainty is
statistical and the second is systematic. The first measurement of the
longitudinal polarization fraction is extracted from the angular analysis of
the $B \to \psi(2S) K^*(892)$ candidates: $\Gamma_L / \Gamma = 0.45 +- 0.11 +-
0.04 $. Our measurements of the decays $B^0 \to \psi(2S) K^0$ and $B^+ \to
\psi(2S) K^*(892)^+$ are first observations.

</DOC>
<DOC>
<DOCNO> 7727 </DOCNO>
Roughening and preroughening transitions in crystal surfaces with


  We investigate phase transitions in a solid-on-solid model where
double-height steps as well as single-height steps are allowed. Without the
double-height steps, repulsive interactions between up-up or down-down step
pairs give rise to a disordered flat phase. When the double-height steps are
allowed, two single-height steps can merge into a double-height step (step
doubling). We find that the step doubling reduces repulsive interaction
strength between single-height steps and that the disordered flat phase is
suppressed. As a control parameter a step doubling energy is introduced, which
is assigned to each step doubling vertex. From transfer matrix type
finite-size-scaling studies of interface free energies, we obtain the phase
diagram in the parameter space of the step energy, the interaction energy, and
the step doubling energy.

</DOC>
<DOC>
<DOCNO> 122841 </DOCNO>
Models for the IR and submm SEDs of normal, starburst and active


  Models for the seds of infrared galaxies are reviewed, with particular
application to hyperluminous infrared galaxies.

</DOC>
<DOC>
<DOCNO> 100974 </DOCNO>
Deformation of Okamoto-Painlev\'e Pairs and Painlev\'e equations


  In this paper, we introduce the notion of generalized rational
Okamoto-Painlev\'e pair (S, Y) by generalizing the notion of the spaces of
initial conditions of Painlev\'e equations. After classifying those pairs, we
will establish an algebro-geometric approach to derive the Painlev\'e
differential equations from the deformation of Okamoto-Painlev\'e pairs by
using the local cohomology groups. Moreover the reason why the Painlev\'e
equations can be written in Hamiltonian systems is clarified by means of the
holomorphic symplectic structure on S - Y. Hamiltonian structures for
Okamoto-Painlev\'e pairs of type $\tilde{E}_7 (= P_{II})$ and $\tilde{D}_8 (=
P_{III}^{\tilde{D}_8})$ are calculated explicitly as examples of our theory.

</DOC>
<DOC>
<DOCNO> 85368 </DOCNO>
Aperture synthesis for gravitational-wave data analysis: Deterministic


  Gravitational wave detectors now under construction are sensitive to the
phase of the incident gravitational waves. Correspondingly, the signals from
the different detectors can be combined, in the analysis, to simulate a single
detector of greater amplitude and directional sensitivity: in short, aperture
synthesis. Here we consider the problem of aperture synthesis in the special
case of a search for a source whose waveform is known in detail: \textit{e.g.,}
compact binary inspiral. We derive the likelihood function for joint output of
several detectors as a function of the parameters that describe the signal and
find the optimal matched filter for the detection of the known signal. Our
results allow for the presence of noise that is correlated between the several
detectors. While their derivation is specialized to the case of Gaussian noise
we show that the results obtained are, in fact, appropriate in a well-defined,
information-theoretic sense even when the noise is non-Gaussian in character.
  The analysis described here stands in distinction to ``coincidence
analyses'', wherein the data from each of several detectors is studied in
isolation to produce a list of candidate events, which are then compared to
search for coincidences that might indicate common origin in a gravitational
wave signal. We compare these two analyses --- optimal filtering and
coincidence --- in a series of numerical examples, showing that the optimal
filtering analysis always yields a greater detection efficiency for given false
alarm rate, even when the detector noise is strongly non-Gaussian.

</DOC>
<DOC>
<DOCNO> 178881 </DOCNO>
Extrapolation of mean-field models to superheavy nuclei


  The extrapolation of self-consistent nuclear mean-field models to the region
of superheavy elements is discussed with emphasis on the extrapolating power of
the models. The predictions of modern mean-field models are confronted with
recent experimental data. It is shown that a final conclusion about the
location of the expected island of spherical doubly-magic superheavy nuclei
cannot be drawn on the basis of the available data.

</DOC>
<DOC>
<DOCNO> 116503 </DOCNO>
Coherent X-Ray Generation with Laser Driven Ions


  Small parts of the electronic wavepacket of a multiple charged ion may still
tunnel through the high Coulomb barrier for a sufficiently intense laser field
of $10^{15}W/cm^2$ and higher. Solving numerically the corresponding
Schr\"odinger equation we find that the periodic recollisions of such a
wavepacket in the oscillating high power laser field will give rise to coherent
X-ray radiation in the multiple keV regime, i.e. substantially higher than
predicted or observed before.

</DOC>
<DOC>
<DOCNO> 170164 </DOCNO>
Trapping of Single Atoms with Single Photons in Cavity QED


  Two recent experiments have reported the trapping of individual atoms inside
optical resonators by the mechanical forces associated with single photons
[Hood et al., Science 287, 1447 (2000) and Pinkse et al., Nature 404, 365
(2000)]. Here we analyze the trapping dynamics in these settings, focusing on
two points of interest. Firstly, we investigate the extent to which
light-induced forces in these experiments are distinct from their free-space
counterparts. Secondly, we explore the quantitative features of the resulting
atomic motion and how these dynamics are mapped onto variations of the
intracavity field. Not surprisingly, qualitatively distinct atomic dynamics
arise as the coupling and dissipative rates are varied. For the experiment of
Hood et al., we show that atomic motion is largely conservative and is
predominantly in radial orbits transverse to the cavity axis. A comparison with
the free-space theory demonstrates that the fluctuations of the dipole force
are suppressed by an order of magnitude. This effect is based upon the
Jaynes-Cummings eigenstates of the atom-cavity system and represents
qualitatively new physics for optical forces at the single-photon level. By
contrast, even in a regime of strong coupling in the experiment of Pinkse et
al., there are only small quantitative distinctions between the free-space
theory and the quantum theory, so it is not clear that description of this
experiment as a novel single-quantum trapping effect is necessary. The atomic
motion is strongly diffusive, leading to an average localization time
comparable to the time for an atom to transit freely through the cavity and to
a reduction in the ability to infer aspects of the atomic motion from the
intracavity photon number.

</DOC>
<DOC>
<DOCNO> 13176 </DOCNO>
Hole spectral functions of LaMnO3


  By use of the orbital t-J model, we calculate the photoemission spectra of
LaMnO3 using the exact diagonalization technique, and interpret our numerics
quite well in the orbital-polaron scenario where the scattering between holes
and orbital excitations is treated within the self-consistent Born
approximation. The quasiparticle bandwidth is found to be of the order of J and
t in the purely Coulombic and Jahn-Teller phononic model, respectively. We
suggest that angle-resolved photoemission spectroscopy experiments allow one to
distinguish between the orbital-polaron scenario and the Jahn-Teller polaron
scenario.

</DOC>
<DOC>
<DOCNO> 39770 </DOCNO>
Cosmic Ray Muon Physics


  We present a review of atmospheric and underground muon flux measurements.
The relevance of these data for the atmospheric neutrino flux computation is
emphasized. Possible sources of systematic errors in the measurements are
discussed, focusing on the sea level muon data. Underground muon data are also
reported.

</DOC>
<DOC>
<DOCNO> 150834 </DOCNO>
Non-BPS D-brane Solutions in Six Dimensional Orbifolds


  Starting with the non-BPS D0-brane solution of IIB/$(-1)^{F_L}I_4$
constructed recently by Eyras and Panda we construct via T-duality the non-BPS
D2-brane and D1-brane solutions of IIB/$(-1)^{F_L}I_4$ and IIA/$(-1)^{F_L}I_4$
predicted by Sen. The D2-brane couples magnetically to the vector field of the
NS5B-brane living in the twisted sector of the Type IIB orbifold, whereas the
D1-brane couples (electrically and magnetically) to the self-dual 2-form
potential of the NS5A-brane that is present in the twisted sector of the Type
IIA orbifold construction. Finally we discuss the eleven dimensional
interpretation of these branes as originating from a non-BPS M1-brane solution
of M-theory orientifolded by $\Omega_\rho I_5$.

</DOC>
<DOC>
<DOCNO> 9966 </DOCNO>
Two-scale localization of wave functions in disordered wires in a weak


  Using the supersymmetry technique combined with the transfer matrix method we
calculate different physical quantities characterizing localization in
disordered wires. In particular, we analyze the density-density correlation
function and study effects of an external magnetic field $H$ on tails of wave
functions. At zero and very strong magnetic fields, we obtain explicit
expressions, valid at arbitrary distances, for all moments and for the entire
distribution function of the density-density correlations. A two-scale decay is
shown to be a typical feature of infinitely long wires at weak magnetic fields:
The far tail of the wave functions decays twice as slow as their main body.
Extending Mott's physical picture for the localized states we present a
qualitative description of the crossover in the magnetic field. Our arguments
can be used for any dimensionality indicating that the concept of the two-scale
localization in a weak magnetic field is a general feature of localization. The
effect is very sensitive to a level smearing and cannot be seen in the
transmittance of a system with metallic leads. This means that the Borland
conjecture may not be used for a numerical check of the two-scale localization.

</DOC>
<DOC>
<DOCNO> 178701 </DOCNO>
Shell model description of "mixed-symmetry" states in 94Mo


  Shell model calculations have been performed for the nucleus 94Mo. The
calculated excitation energies and electromagnetic properties of low-lying
states are in good agreement with the data, which include states with
mixed-symmetry (MS) assignments in previous interacting boson model studies. In
the shell model large isoscalar E2 matrix elements are found between states
with MS assignments indicating that they form a class of states with similar
proton-neutron symmetry.

</DOC>
<DOC>
<DOCNO> 68321 </DOCNO>
Neutrino Exotica in the Skew E_6 Left-Right Model


  With the particle content of the 27 representation of E_6, a skew left-right
supersymmetric gauge model was proposed many years ago, with a variety of
interesting phenomenological implications. The neutrino sector of this model
offers a natural framework for obtaining small Majorana masses for nu_e, nu_mu,
and nu_tau, with the added bonus of accommodating 2 light sterile neutrinos.

</DOC>
<DOC>
<DOCNO> 68239 </DOCNO>
Model independent bounds on the tau lepton electromagnetic and weak


  Using LEP1, SLD and LEP2 data, for tau lepton production, and data from CDF,
D0 and LEP2, for W decays into tau leptons, we set model independent limits on
non-standard electromagnetic and weak magnetic moments of the tau lepton. The
most general effective Lagrangian giving rise to tau moments is used without
further assumptions. Precise bounds ($2\sigma$) on the non-standard model
contributions to tau electromagnetic ($-0.007<a_\gamma< 0.005$), tau Z-magnetic
($-0.0024 <a_Z< 0.0025$) and tau W-magnetic ($-0.003 < \kappa^W < 0.004$)
dipole moments are set from the analysis.

</DOC>
<DOC>
<DOCNO> 122892 </DOCNO>
Microscopic Theory of the Nuclear Equation of State and Neutron Star


  The Bethe-Brueckner-Goldstone many-body theory of the Nuclear Equation of
State is reviewed in some details. In the theory, one performs an expansion in
terms of the Brueckner two-body scattering matrix and an ordering of the
corresponding many-body diagrams according to the number of their hole-lines.
Recent results are reported, both for symmetric and for pure neutron matter,
based on realistic two-nucleon interactions. It is shown that there is strong
evidence of convergence in the expansion. Once three-body forces are
introduced, the phenomenological saturation point is reproduced and the theory
is applied to the study of neutron star properties. One finds that in the
interior of neutron stars the onset of hyperons strongly softens the Nuclear
Equation of State. As a consequence, the maximum mass of neutron stars turns
out to be at the lower limit of the present phenomenological observation.

</DOC>
<DOC>
<DOCNO> 8288 </DOCNO>
Comment on ``Triviality of the Ground State Structure in Ising Spin


  We show that the evidence of cond-mat/9906323 does not discriminate among
droplet model and mean field like behavior.

</DOC>
<DOC>
<DOCNO> 170695 </DOCNO>
Quantum versus Classical Domains for Teleportation with Continuous


  Fidelity F{classical} = 1/2 has been established as setting the boundary
between classical and quantum domains in the teleportation of coherent states
of the electromagnetic field (S. L. Braunstein, C. A. Fuchs, and H. J. Kimble,
J. Mod. Opt. 47, 267 (2000)). Two recent papers by P. Grangier and F. Grosshans
(quant-ph/0009079 and quant-ph/0010107) introduce alternate criteria for
setting this boundary and as a result claim that the appropriate boundary
should be F = 2/3. Although larger fidelities would lead to enhanced
teleportation capabilities, we show that the new conditions of Grangier and
Grosshans are largely unrelated to the questions of entanglement and
Bell-inequality violations that they take to be their primary concern. With
regard to the quantum-classical boundary, we demonstrate that fidelity
F{classical} = 1/2 remains the appropriate point of demarcation. The claims of
Grangier and Grosshans to the contrary are simply wrong, as we show by an
analysis of the conditions for nonseparability (that complements our earlier
treatment) and by explicit examples of Bell-inequality violations.

</DOC>
<DOC>
<DOCNO> 13381 </DOCNO>
Cellular Models for River Networks


  A cellular model introduced for the evolution of the fluvial landscape is
revisited using extensive numerical and scaling analyses. The basic network
shapes and their recurrence especially in the aggregation structure are then
addressed. The roles of boundary and initial conditions are carefully analyzed
as well as the key effect of quenched disorder embedded in random pinning of
the landscape surface. It is found that the above features strongly affect the
scaling behavior of key morphological quantities. In particular, we conclude
that randomly pinned regions (whose structural disorder bears much physical
meaning mimicking uneven landscape-forming rainfall events, geological
diversity or heterogeneity in surficial properties like vegetation, soil cover
or type) play a key role for the robust emergence of aggregation patterns
bearing much resemblance to real river networks.

</DOC>
<DOC>
<DOCNO> 13190 </DOCNO>
Minimal vertex covers on finite-connectivity random graphs - a


  The minimal vertex-cover (or maximal independent-set) problem is studied on
random graphs of finite connectivity. Analytical results are obtained by a
mapping to a lattice gas of hard spheres of (chemical) radius one, and they are
found to be in excellent agreement with numerical simulations. We give a
detailed description of the replica-symmetric phase, including the size and the
entropy of the minimal vertex covers, and the structure of the unfrozen
component which is found to percolate at connectivity $c\simeq 1.43$. The
replica-symmetric solution breaks down at $c=e\simeq 2.72$. We give a simple
one-step replica symmetry broken solution, and discuss the problems in
interpretation and generalization of this solution.

</DOC>
<DOC>
<DOCNO> 169635 </DOCNO>
Entanglement and Open Systems in Algebraic Quantum Field Theory


  Entanglement has long been the subject of discussion by philosophers of
quantum theory, and has recently come to play an essential role for physicists
in their development of quantum information theory. In this paper we show how
the formalism of algebraic quantum field theory (AQFT) provides a rigorous
framework within which to analyze entanglement in the context of a fully
relativistic formulation of quantum theory. What emerges from the analysis are
new practical and theoretical limitations on an experimenter's ability to
perform operations on a field in one spacetime region that can disentangle its
state from the state of the field in other spacelike-separated regions. These
limitations show just how deeply entrenched entanglement is in relativistic
quantum field theory, and yield a fresh perspective on the ways in which the
theory differs conceptually from both standard nonrelativistic quantum theory
and classical relativistic field theory.

</DOC>
<DOC>
<DOCNO> 121434 </DOCNO>
First images on the sky from a hyper telescope


  We show star images obtained with a miniature ``densified pupil imaging
interferometer'' also called a hyper-telescope. The formation of such images
violates a ``golden rule of imaging interferometers'' which appeared to forbid
the use of interferometric arrangements differing from a Fizeau interferometer.
These produce useless images when the sub-apertures spacing is much wider than
their size, owing to diffraction through the sub-apertures. The hyper-telescope
arrangement solves these problems opening the way towards multi-kilometer
imaging arrays in space. We experimentally obtain an intensity gain of 24 +- 3X
when a densified-pupil interferometer is compared to an equivalent Fizeau-type
interferometer and show images of the double star alpha Gem. The initial
results presented confirm the possibility of directly obtaining high resolution
and high dynamic range images in the recombined focal plane of a large
interferometer if enough elements are used.

</DOC>
<DOC>
<DOCNO> 70601 </DOCNO>
Supersymmetric Unification at the Millenium


  We argue that the discovery of neutrino mass effects at Super-Kamiokande
implies a clear logical chain leading from the Standard Model, through the MSSM
and the recently developed Minimal Left Right Supersymmetric models with a
renormalizable see-saw mechanism for neutrino mass, to Left Right symmetric
SUSY GUTS : in particular, SO(10) and $SU(2)_L \times SU(2)_R\times SU(4)_c$.
The progress in constructing such GUTS explicitly is reviewed and their
testability/falsifiability by lepton flavour violation and proton decay
measurements emphasized. Susy violations of the survival principle and the
interplay between third generation Yukawa coupling unification and the
structurally stable IR attractive features of the RG flow in SUSY GUTS are also
discussed .

</DOC>
<DOC>
<DOCNO> 8138 </DOCNO>
On depolarisation level shift in spherical QD


  A giant level shift, resulted from the interaction of an electron in a
spherical quantum dot with zero--point oscillations of confined modes of the
electric field, is divulged. The energy correction depends on the dot radius.
This size scaling of the depolarisation effect is computed semiclassically. A
change of the optical properties of the matrix surrounding the dot provides a
method to study the shift experimentally.

</DOC>
<DOC>
<DOCNO> 12391 </DOCNO>
Double-Occupancy Errors, Adiabaticity, and Entanglement of Spin-Qubits


  Quantum gates that temporarily increase singlet-triplet splitting in order to
swap electronic spins in coupled quantum dots, lead inevitably to a finite
double-occupancy probability for both dots. By solving the time-dependent
Schr\"odinger equation for a coupled dot model, we demonstrate that this does
not necessarily lead to quantum computation errors. Instead, the coupled dot
ground state evolves quasi-adiabatically for typical system parameters so that
the double-occupancy probability at the completion of swapping is negligibly
small. We introduce a measure of entanglement which explicitly takes into
account the possibilty of double occupancies and provides a necessary and
sufficient criterion for entangled states.

</DOC>
<DOC>
<DOCNO> 122773 </DOCNO>
XMM-Newton observation of the Lockman Hole; I. The X-ray Data


  We report on the first deep X-ray survey with the XMM-Newton observatory
during the performance verification phase. The field of the Lockman Hole, one
of the best studied sky areas over a very wide range of wavelengths, has been
observed. A total of ~100 ksec good exposure time has been accumulated.
Combining the images of the European Photon Imaging Camera (EPIC) detectors we
reach a flux limit of 0.31, 1.4 and 2.4 X 10^{-15} erg cm^{-2} s^{-1},
respectively in the 0.5-2, 2-10, and 5-10 keV band. Within an off-axis angle of
10 arcmin we detect 148, 112 and 61 sources, respectively. The log(N)-log(S)
relation in the three bands is compared with previous results. In particular in
the 5-10 keV band these observations present the deepest X-ray survey ever,
about a factor 20 more sensitive than the previous BeppoSAX observations. Using
X-ray spectral diagnostics and the set of previously known, spectroscopically
identified ROSAT sources in the field, the new sources can be classified.
XMM-Newton detects a significant number (~40%) of X-ray sources with hard,
probably intrinsically absorbed X-ray spectra, confirming a prediction of the
population synthesis models for the X-ray background.

</DOC>
<DOC>
<DOCNO> 14011 </DOCNO>
Phase separation in mixtures of colloids and long ideal polymer coils


  Colloidal suspensions with free polymer coils which are larger than the
colloidal particles are considered. The polymer-colloid interaction is modeled
by an extension of the Asakura-Oosawa model. Phase separation occurs into
dilute and dense fluid phases of colloidal particles when polymer is added. The
critical density of this transition tends to zero as the size of the polymer
coils diverges.

</DOC>
<DOC>
<DOCNO> 9887 </DOCNO>
Scaling function for the noisy Burgers equation in the soliton


  We derive the scaling function for the one dimensional noisy Burgers equation
in the two-soliton approximation within the weak noise canonical phase space
approach. The result is in agreement with an earlier heuristic expression and
exhibits the correct scaling properties. The calculation presents the first
step in a many body treatment of the correlations in the Burgers equation.

</DOC>
<DOC>
<DOCNO> 10610 </DOCNO>
Classification of phase transitions of finite Bose-Einstein condensates


  We present a detailed description of a classification scheme for phase
transitions in finite systems based on the distribution of Fisher zeros of the
canonical partition function in the complex temperature plane. We apply this
scheme to finite Bose-systems in power law traps within a semi-analytic
approach with a continuous one-particle density of states $\Omega(E)\sim
E^{d-1}$ for different values of $d$ and to a three dimensional harmonically
confined ideal Bose-gas with discrete energy levels. Our results indicate that
the order of the Bose-Einstein condensation phase transition sensitively
depends on the confining potential.

</DOC>
<DOC>
<DOCNO> 170105 </DOCNO>
A generalized Weyl relation approach to the time operator and its


  The time operator, an operator which satisfies the canonical commutation
relation with the Hamiltonian, is investigated, on the basis of a certain
algebraic relation for a pair of operators T and H, where T is symmetric and H
self-adjoint. This relation is equivalent to the Weyl relation, in the case of
self-adjoint T, and is satisfied by the Aharonov-Bohm time operator T_0 and the
free Hamiltonian H_0 for the one-dimensional free-particle system. In order to
see the qualitative properties of T_0, the operators T and H satisfying this
algebraic relation are examined. In particular, it is shown that the standard
deviation of T is directly connected to the survival probability, and H is
absolutely continuous. Hence, it is concluded that the existence of the
operator T implies the existence of scattering states. It is also shown that
the minimum uncertainty states do not exist. Other examples of these operators
T and H, than the one-dimensional free-particle system, are demonstrated.

</DOC>
<DOC>
<DOCNO> 80831 </DOCNO>
Regulated chiral gauge theories


  Noncompact chiral abelian gauge theories are defined on the lattice using the
overlap formalism. The main definitions are presented, the role of anomaly
cancelation is discussed, and the triviality issue in four dimensions is
explained.

</DOC>
<DOC>
<DOCNO> 122680 </DOCNO>
Efficiency and spectrum of internal gamma-ray burst shocks


  We present an analysis of the Internal Shock Model of GRBs, where gamma-rays
are produced by internal shocks within a relativistic wind. We show that
observed GRB characteristics impose stringent constraints on wind and source
parameters. We find that a significant fraction, of order 20 %, of the wind
kinetic energy can be converted to radiation, provided the distribution of
Lorentz factors within the wind has a large variance and provided the minimum
Lorentz factor is higher than 10^(2.5)L_(52)^(2/9), where L=10^(52)L_(52)erg/s
is the wind luminosity. For a high, >10 %, efficiency wind, spectral energy
breaks in the 0.1 to 1 MeV range are obtained for sources with dynamical time
R/c < 1 ms, suggesting a possible explanation for the observed clustering of
spectral break energies in this range. The lower limit to wind Lorenz factor
and the upper limit, around (R/10^7 cm)^(-5/6) MeV to observed break energies
are set by Thomson optical depth due to electron positron pairs produced by
synchrotron photons. Natural consequences of the model are absence of bursts
with peak emission energy significantly exceeding 1 MeV, and existence of low
luminosity bursts with low, 1 keV to 10 keV, break energies.

</DOC>
<DOC>
<DOCNO> 68377 </DOCNO>
Phase transitions from preheating in gauge theories


  We show by studying the Abelian Higgs model with numerical lattice
simulations that non-thermal phase transitions arising out of preheating after
inflation are possible in gauge-Higgs models under rather general
circumstances. This may lead to the formation of gauged topological defects
and, if the scale at which inflation ends is low enough, to electroweak
baryogenesis after preheating.

</DOC>
<DOC>
<DOCNO> 100630 </DOCNO>
Commuting self-adjoint extensions of symmetric operators defined from


  We consider the problem of finding commuting self-adjoint extensions of the
partial derivatives {(1/i)(\partial/\partial x_j):j=1,...,d} with domain
C_c^\infty(\Omega) where the self-adjointness is defined relative to
L^2(\Omega), and \Omega is a given open subset of R^d. The measure on \Omega is
Lebesgue measure on R^d restricted to \Omega. The problem originates with I.E.
Segal and B. Fuglede, and is difficult in general. In this paper, we provide a
representation-theoretic answer in the special case when \Omega=I\times\Omega_2
and I is an open interval. We then apply the results to the case when \Omega is
a d-cube, I^d, and we describe possible subsets \Lambda of R^d such that
{e^(i2\pi\lambda \dot x) restricted to I^d:\lambda\in\Lambda} is an orthonormal
basis in L^2(I^d).

</DOC>
<DOC>
<DOCNO> 12000 </DOCNO>
Energy transduction in periodically driven non-Hermitian systems


  We show a new mechanism to extract energy from non-equilibrium fluctuations
typical of periodically driven non-Hermitian systems. The transduction of
energy between the driving force and the system is revealed by an
\emph{anomalous} behavior of the susceptibility, leading to a diminution of the
dissipated power and consequently to an improvement of the transport
properties. The general framework is illustrated by the analysis of some
relevant cases.

</DOC>
<DOC>
<DOCNO> 71997 </DOCNO>
Sensitive Search for a Permanent Muon Electric Dipole Moment


  We are proposing a new method to carry out a dedicated search for a permanent
electric dipole moment (EDM) of the muon with a sensitivity at a level of
10^{-24} e cm. The experimental design exploits the strong motional electric
field sensed by relativistic particles in a magnetic storage ring. As a key
feature, a novel technique has been invented in which the g-2 precession is
compensated with radial electric field. This technique will benefit greatly
when the intense muon sources advocated by the developers of the muon storage
rings and the muon colliders become available.

</DOC>
<DOC>
<DOCNO> 84218 </DOCNO>
Fiber with Intrinsic Action on a 1+1 Dimensional Spacetime


  I construct an algebraic model for a typical fiber on a 1+1 dimensional
spacetime. The vector space comprising the fiber is composed of elements formed
from the direct product of two copies of an element x in the D2=C2xC2 finite
group algebra over the real numbers. The fiber contains subspaces whose
elements are associated with the tangent and momentum vectors of trajectories
in the manifold. The fiber also contains a subspace whose elements are
associated with the local flow of action of each trajectory. The condition of
minimum action translates into a constraint on the original vector x in the
direct product structure.

</DOC>
<DOC>
<DOCNO> 119800 </DOCNO>
Time Domain Analysis of Variability in Cygnus X-1: Constraints on the


  We use time domain analysis techniques to investigate the rapid variability
of Cygnus X-1. We show that the cross-correlation functions between hard and
soft energy bands reach values very close to unity and peak at a lag of less
than 2 millisecond for energies separated by a factor of 10. This confirms that
the process that produces X-ray photons at different energies is extremely
coherent on short time scales and strongly constrains emission models proposed
to explain Fourier-frequency-dependent time lags. We present autocorrelation
functions at different energies, and note their widths decrease with increasing
energy. We show that the extended Compton corona model produces
auto-correlation functions whose widths increase with increasing energy, that
the model of cylindrical waves moving inward through a transition disk has too
large a peak lag in the cross-correlation function. Models of magnetic flaring
and of drifting blobs in a hot corona can qualitatively fit the observations.

</DOC>
<DOC>
<DOCNO> 120939 </DOCNO>
Cosmological-Model-Parameter Determination from Satellite-Acquired Type


  We examine the constraints that satellite-acquired Type Ia and IIP supernova
apparent magnitude versus redshift data will place on cosmological model
parameters in models with and without a constant or time-variable cosmological
constant $\Lambda$. High-quality data which could be acquired in the near
future will result in tight constraints on these parameters. For example, if
all other parameters of a spatially-flat model with a constant $\Lambda$ are
known, the supernova data should constrain the non-relativistic matter density
parameter $\Omega_0$ to better than 1% (2%, 0.5%) at 1$\sigma$ with neutral
(worst case, best case) assumptions about data quality.

</DOC>
<DOC>
<DOCNO> 13655 </DOCNO>
Limits to error correction in quantum chaos


  We study the correction of errors that have accumulated in an entangled state
of spins as a result of unknown local variations in the Zeeman energy (B) and
spin-spin interaction energy (J). A non-degenerate code with error rate kappa
can recover the original state with high fidelity within a time kappa^1/2 /
max(B,J) --- independent of the number of encoded qubits. Whether the
Hamiltonian is chaotic or not does not affect this time scale, but it does
affect the complexity of the error-correcting code.

</DOC>
<DOC>
<DOCNO> 84539 </DOCNO>
Boson Condensation in an Einstein Universe


  In this paper we investigate the Bose-Einstein condensation of massive spin-1
particles in an Einstein universe. The system is considered under relativistic
conditions taking into consideration the possibility of particle-antiparticle
pair production. An exact expression for the charge density is obtained, then
certain approximations are employed in order to obtain the solutions in closed
form. A discussion of the approximations employed in this and other work is
given. The effects of finite-size and spin-curvature coupling are emphasized.

</DOC>
<DOC>
<DOCNO> 11323 </DOCNO>
BCS superfluidity in ultracold gases with unequal atomic populations


  We consider the existence of a BCS superfluid phase in $^{6}$Li due to the
pairing of two hyperfine states with unequal number of atoms. We show that the
domain of existence for this phase will be increased to a very large extent in
the vicinity of the threshold for collapse. This is due to the presence of a
new phase with anisotropic order parameter. This phase is induced by the
anisotropic part of the scattering, linked to the indirect interaction between
atoms through density fluctuation exchange.

</DOC>
<DOC>
<DOCNO> 68587 </DOCNO>
Higgs induced light leptoquark-diquark mixing and proton decay


  In low energy phenomenology to avoid the strong constraints of proton decay
it is usually assumed that light ($\approx $ 250 Gev) leptoquarks couple only
to quark-lepton pairs and light diquarks couple only to quark pairs. In this
paper we present two specific examples where the higgs induced mixing between
leptoquarks and diquarks through trilinear interaction terms reintroduces the
troublesome couplings and gives rise to proton decay. The bound on the unknown
parameters of this scenario that arise from proton life time has been derived.

</DOC>
<DOC>
<DOCNO> 119917 </DOCNO>
Exploring the gravitationally lensed system HE 1104-1805: Near-IR


  (Abridged) A new technique for the spatial deconvolution of spectra is
applied to near-IR (0.95 - 2.50 micron) NTT/SOFI spectra of the lensed,
radio-quiet quasar HE 1104-1805. The continuum of the lensing galaxy is
revealed between 1.5 and 2.5 micron. It is used in combination with previous
optical and IR photometry to infer a plausible redshift in the range 0.8 < z <
1.2. Modeling of the system shows that the lens is probably composed of the red
galaxy seen between the quasar images and a more extended component associated
with a galaxy cluster with fairly low velocity dispersion (~ 575 km/s). The
spectra of the two lensed images of the source show no trace of reddening at
the redshift of the lens nor at the redshift of the source. Additionally, the
difference between the spectrum of the brightest component a nd that of a
scaled version of the faintest component is a featureless continuum. Broad and
narrow emission lines, including the FeII features, are perfectly subtracted.
The very good quality of our spectrum makes it possible to fit precisely the
optical Fe II feature, taking into account the underlying continuum over a wide
wavelength range. HE 1104-1805 can be classified as a weak Fe II emitter.
Finally, the slope of the continuum in the brightest image is steeper than the
continuum in the faintest image and supports the finding by Wisotzki et al.
(1993) that the brightest image is microlensed. This is particularly
interesting in view of the new source reconstruction methods from
multiwavelength photometric monitoring.

</DOC>
<DOC>
<DOCNO> 150719 </DOCNO>
Wilson loop via AdS/CFT duality


  The Wilson loop in N=4 supersymmetric Yang-Mills theory admits a dual
description as a macroscopic string configuration in the adS/CFT
correspondence. We discuss the correction to the quark anti-quark potential
arising from the fluctuations of the superstring.

</DOC>
<DOC>
<DOCNO> 170541 </DOCNO>
From Many to One: On Starting a Quantum Computation


  Quantum computing algorithms require that the quantum register be initially
present in a superposition state. To achieve this, we consider the practical
problem of creating a coherent superposition state of several qubits. Owing to
considerations of quantum statistics, this requires that the entropy of the
system go down. This, in turn, has two practical implications: (i) the initial
state cannot be controlled; (ii) the temperature of the system must be reduced.

</DOC>
<DOC>
<DOCNO> 117946 </DOCNO>
Fossils of turbulence and non-turbulence in the primordial universe: the


  Was the primordial universe turbulent or non-turbulent soon after the Big
Bang? How did the hydrodynamic state of the early universe affect the formation
of structure from gravitational forces, and how did the formation of structure
by gravity affect the hydrodynamic state of the flow? What can be said about
the dark matter that comprises 99.9 % of the mass of the universe according to
most cosmological models? Space telescope measurements show answers to these
questions persist literally frozen as fossils of the primordial turbulence and
nonturbulence that controlled structure formation, contrary to standard
cosmology which relies on the erroneous Jeans 1902 linear-inviscid-acoustic
theory and a variety of associated misconceptions (e. g., cold dark matter).
When effects of viscosity, turbulence, and diffusion are included, vastly
different structure scenarios and a clear explanation for the dark matter
emerge. From Gibson's 1996 theory the baryonic (ordinary) dark matter is
comprised of proto-globular-star-cluster (PGC) clumps of hydrogenous planetoids
termed ``primordial fog particles''(PFPs), observed by Schild 1996 as ``rogue
planets ... likely to be the missing mass'' of a quasar lensing galaxy. The
weakly collisional non-baryonic dark matter diffuses to form outer halos of
galaxies and galaxy clusters.

</DOC>
<DOC>
<DOCNO> 72096 </DOCNO>
QCD Loop Corrections to Top Production and Decay


  We discuss the computation of QCD virtual corrections to the top production
and decay process at linear colliders. The double pole approximation (DPA) is
used, and we comment on similarities and differences between our results and
results obtained in a similar framework for the QED corrections to the W pair
production process at LEPII.

</DOC>
<DOC>
<DOCNO> 118286 </DOCNO>
Energy implications of temperature fluctuations in photoionized plasma


  We quantify the energy radiated through all the collisionally excited lines
in a photoionized nebula which is permeated by temperature fluctuations. We
assume that these correspond to hot spots which are the results of an unknown
heating process distinct from the photoelectric heating. We consider all the
effects of using a higher mean temperature (as compared to the equilibrium
temperature) due to the fluctuations not only on each emission line but also on
the ionization state of the gas. If this yet unknown process was to radiate a
fixed amount of energy, we find that the fluctuations should correlate with
metallicity Z when it exceeds 0.7 solar. The excess energy radiated in the
lines as a result of the fluctuations is found to scale proportionally to their
amplitude t^2. When referred to the total energy absorbed through
photoionization, the excess energy is comparable in magnitude to t^2.

</DOC>
<DOC>
<DOCNO> 70122 </DOCNO>
Geometric scaling for the total gamma^* p cross section in the low x


  We observe that the saturation model of deep inelastic scattering, which
successfully describes inclusive and diffractive data at small x, predicts a
geometric scaling of the total gamma^* p cross section in the region of small
Bjorken variable x. The geometric scaling in this case means that the cross
section is a function of only one dimensionless variable tau = Q^2 R_0^2(x),
where the function R_0(x) (called saturation radius) decreases with decreasing
x. We show that the experimental data from HERA in the region x<0.01 confirm
the expectations of this scaling over a very broad region of Q^2. We suggest
that the geometric scaling is more general than the saturation model.

</DOC>
<DOC>
<DOCNO> 150731 </DOCNO>
D-Brane Gauge Theories from Toric Singularities and Toric Duality


  Via partial resolution of Abelian orbifolds we present an algorithm for
extracting a consistent set of gauge theory data for an arbitrary toric variety
whose singularity a D-brane probes. As illustrative examples, we tabulate the
matter content and superpotential for a D-brane living on the toric del Pezzo
surfaces as well as the zeroth Hirzebruch surface. Moreover, we discuss the
non-uniqueness of the general problem and present examples of vastly different
theories whose moduli spaces are described by the same toric data. Our methods
provide new tools for calculating gauge theories which flow to the same
universality class in the IR. We shall call it ``Toric Duality.''

</DOC>
<DOC>
<DOCNO> 178387 </DOCNO>
Shell Corrections for Finite-Depth Deformed Potentials: Green's Function


  Shell corrections of the finite deformed Woods-Saxon potential are calculated
using the Green's function method and the generalized Strutinsky smoothing
procedure. They are compared with the results of the standard prescription
which are affected by the spurious contribution from the unphysical particle
gas. In the new method, the shell correction approaches the exact limit
provided that the dimension of the single-particle (harmonic oscillator) basis
is sufficiently large. For spherical potentials, the present method is faster
than the exact one in which the contribution from the particle continuum states
is explicitly calculated. For deformed potentials, the Green's function method
offers a practical and reliable way of calculating shell corrections for weakly
bound nuclei.

</DOC>
<DOC>
<DOCNO> 71633 </DOCNO>
QCD Factorization and CP Asymmetries in Hadronic B Decays


  We review recent advances in the theory of strong-interaction effects and
final-state interactions in hadronic weak decays of heavy mesons. In the
heavy-quark limit, the amplitudes for most nonleptonic, two-body B decays can
be calculated from first principles and expressed in terms of semileptonic form
factors and light-cone distribution amplitudes. We summarize the main features
of this novel QCD factorization and discuss its phenomenological applications
to B->D^(*)+L decays (with L a light meson), and to the rare charmless decays
B->pi+K and B->pi+pi.

</DOC>
<DOC>
<DOCNO> 99444 </DOCNO>
Combed 3-Manifolds with Concave Boundary, Framed Links, and


  We provide combinatorial realizations, according to the usual objects/moves
scheme, of the following three topological categories: (1) pairs (M,v) where M
is a 3-manifold (up to diffeomorphism) and v is a (non-singular vector) field,
up to homotopy; here possibly the boundary of M is non-empty and v may be
tangent to the boundary, but only in a concave fashion, and homotopy should
preserve tangency type; (2) framed links L in M, up to framed isotopy; (3)
triples (M,v,L), with (M,v) as above and L transversal to v, up to
pseudo-Legendrian isotopy (transversality-preserving simultaneous homotopy of v
and isotopy of L). All realizations are based on the notion of branched
standard spine, and build on results previously obtained. Links are encoded by
means of diagrams on branched spines, where the diagram is smooth with respect
to the branching. Several motivations for being interested in combinatorial
realizations of the topological categories considered in this paper are given
in the introduction. The encoding of links is suitable for the comparison of
the framed and the pseudo-Legendrian categories, and some applications are
given in connection with contact structures, torsion and finite-order
invariants. An estension of Trace's notion of winding number of a knot diagram
is introduced and discussed.

</DOC>
<DOC>
<DOCNO> 40393 </DOCNO>
Measurement of |V_{ub}/V_{cb}| (and |V_{ub}|) in Exclusive Nonleptonic


  We have studied extracting $|\vub/\vcb|$ by calculating the ratios ${\cal
B}(\bar{B}^0\to D_s^{(*)-}(\pi^+,\rho^+))/{\cal B}(\bar{B}^0\to
D_s^{(*)-}D^{(*)+})$ including penguin effects within the factorization
assumption. The ratios involving $\bar{B}^0\to D_s^-D^{+}$ mode have
considerable penguin corrections ($\sim 15%$ at the amplitude level), but those
involving $\bar{B}^0\to D_s^-D^{*+}$ mode have relatively small penguin
corrections. On the other hand, the $\bar{B}^0\to D_s^-D^{+}$ mode has smaller
form-factor dependance. Therefore, these ratios complement each other in
measuring $\vub/\vcb$. The theoretical uncertainty from the hadronic form
factors in our method is at the level of 15%, which is comparable to the
model-dependence uncertainty of about 20% in the measurement of $| \vub/\vcb |$
from the exclusive semileptonic B decays. Using the newest upper limit on $B\to
D_s \pi$ decay from CLEO, our method sets an upper limit $| \vub/\vcb | < 0.13$
which is very close to the measured values from the semileptonic B decays. We
also discuss the possible breaking of factorization assumption.

</DOC>
<DOC>
<DOCNO> 178968 </DOCNO>
$\eta^\prime$ photoproduction near threshold


  In this work, the $\eta^\prime$ meson photoproduction near threshold is
studied in the quark model framework. A pseudovector effective Lagrangian is
introduced for the $\eta^\prime NN$ coupling and the newly published data from
the SAPHIR Collaboration provide good constraints to this parameter.
Corrections of order $O(1/m_q^2)$ for the electromagnetic interaction vertex
are taken into account, which produce corrections of order $O(1/m_q^3)$ to the
transition amplitude for $\gamma p\to \eta^\prime p$. Some low-lying
resonances, $S_{11}(1535)$, $P_{13}(1720)$, and $P_{13}(1900)$ are found to
have significant contributions. A bump structure around $E_\gamma\approx$ 2 GeV
is found arising from the $n=3$ terms in the harmonic oscillator basis. The
beam polarization asymmetries are predicted and can be tested against the
forthcoming data from GRAAL.

</DOC>
<DOC>
<DOCNO> 9933 </DOCNO>
Stochastic Ballistic Annihilation and Coalescence


  We study a class of stochastic ballistic annihilation and coalescence models
with a binary velocity distribution in one dimension. We obtain an exact
solution for the density which reveals a universal phase diagram for the
asymptotic density decay. By universal we mean that all models in the class are
described by a single phase diagram spanned by two reduced parameters. The
phase diagram reveals four regimes, two of which contain the previously studied
cases of ballistic annihilation. The two new phases are a direct consequence of
the stochasticity. The solution is obtained through a matrix product approach
and builds on properties of a q-deformed harmonic oscillator algebra.

</DOC>
<DOC>
<DOCNO> 118941 </DOCNO>
The Population of Faint Transients in the Galactic Centre


  BeppoSAX has detected a population of faint transient X-ray sources in the
Galactic Centre. I show that a simple irradiated-disc picture gives a
consistent fit to the properties of this population, and that it probably
consists of low-mass X-ray binaries which have evolved beyond their minimum
periods ~80 min. Since all post-minimum systems are transient, and neutron-star
LMXBs are more common than black-hole LMXBs in the Galaxy, the majority of
these systems should contain neutron stars, as observed. This picture predicts
that the Galactic Centre transients should have orbital periods in the range
\~80-120 minutes, and that most of them should repeat in the next few years. In
this case, the total number of post-minimum transients in the Galaxy would be
considerably smaller than the usual estimates of its total LMXB population. I
discuss possible reasons for this.

</DOC>
<DOC>
<DOCNO> 83374 </DOCNO>
Improved Algorithms for 3-Coloring, 3-Edge-Coloring, and Constraint


  We consider worst case time bounds for NP-complete problems including 3-SAT,
3-coloring, 3-edge-coloring, and 3-list-coloring. Our algorithms are based on a
constraint satisfaction (CSP) formulation of these problems; 3-SAT is
equivalent to (2,3)-CSP while the other problems above are special cases of
(3,2)-CSP. We give a fast algorithm for (3,2)-CSP and use it to improve the
time bounds for solving the other problems listed above. Our techniques involve
a mixture of Davis-Putnam-style backtracking with more sophisticated matching
and network flow based ideas.

</DOC>
<DOC>
<DOCNO> 9212 </DOCNO>
On the symmetry and uniqueness of solutions of the Ginzburg-Landau


  In this paper, we study the Ginzburg-Landau equations for a two dimensional
domain which has small size. We prove that if the domain is small, then the
solution has no zero, that is no vortex. More precisely, we show that the order
parameter $\Psi$ is almost constant. Additionnally, we obtain that if the
domain is a disc of small radius, then any non normal solution is symmetric and
unique. Then, in the case of a slab, that is a one dimensional domain, we use
the same method to derive that solutions are symmetric. The proofs use a priori
estimates and the Poincar\'e inequality.

</DOC>
<DOC>
<DOCNO> 170567 </DOCNO>
Quantum trajectories, real, surreal or an approximation to a deeper


  The proposal that the one-parameter solutions of the real part of the
Schrodinger equation (quantum Hamilton-Jacobi equation) can be regarded as
`quantum particle trajectories' has received considerable attention recently.
Opinions as to their significance differ. Some argue that they do play a
fundamental role as actual particle trajectories, others regard them as mere
metaphysical appendages without any physical significance. Recent work has
claimed that in some cases the Bohm approach gives results that disagree with
those obtained from standard quantum mechanics and, in consequence, with
experiment. Furthermore it is claimed that these trajectories have such
unacceptable properties that they can only be considered as `surreal'. We
re-examine these questions and show that the specific objections raised by
Englert, Scully, Sussmann and Walther cannot be sustained. We also argue that
contrary to their negative view, these trajectories can provide a deeper
insight into quantum processes.

</DOC>
<DOC>
<DOCNO> 101343 </DOCNO>
Isoperimetric and Universal Inequalities for Eigenvalues


  This paper reviews many of the known inequalities for the eigenvalues of the
Laplacian and bi-Laplacian on bounded domains in Euclidean space. In
particular, we focus on isoperimetric inequalities for the low eigenvalues of
the Dirichlet and Neumann Laplacians and of the vibrating clamped plate problem
(i.e., the biharmonic operator with ``Dirichlet'' boundary conditions). We also
discuss the known universal inequalities for the eigenvalues of the Dirichlet
Laplacian and the vibrating clamped plate and buckling problems and go on to
present some new ones. Some of the names associated with these inequalities are
Rayleigh, Faber-Krahn, Szego-Weinberger, Payne-Polya-Weinberger, Sperner,
Hile-Protter, and H. C. Yang. Occasionally, we will also comment on extensions
of some of our inequalities to bounded domains in other spaces, specifically,
S^n or H^n.

</DOC>
<DOC>
<DOCNO> 70258 </DOCNO>
QCD Calculations of Heavy Quarkonium States


  Recent results on the QCD analysis of bound states of heavy $\bar{q}q$ quarks
are reviewed, paying attention to what can be derived from the theory with a
reasonable degree of rigour. We report a calculation of $\bar{b}c$ bound
states; a very precise evaluation of $b, c$ quark masses from quarkonium
spectrum; the NNLO evaluation of $\Upsilon\to e^+e^-$; and a discussion of
power corrections. For the $b$ quark {\sl pole} mass we get, including
$O(m_c^2/m_b^2)$ and $O(\alpha_s^5\log \alpha_s)$ corrections,
$m_b=5.020\pm0.058 GeV$; and for the $\bar{MS}$ mass the result, correct to
$O(\alpha_s^3)$, $O(m_c^2/m_b^2)$, $\bar{m}_b(\bar{m}_b)=4.286\pm0.036 GeV$.
For the decay $\Upsilon\to e^+e^-$, higher corrections are too large to permit
a reliable calculation, but we can predict a toponium width of $13\pm1 keV$.

</DOC>
<DOC>
<DOCNO> 9122 </DOCNO>
Electronic Properties of Ultra-Thin Aluminum Nanowires


  We have carried out first principles electronic structure and total energy
calculations for a series of ultrathin aluminum nanowires, based on structures
obtained by relaxing the model wires of Gulseren et al. The number of
conducting channels is followed as the wires radius is increased. The results
suggest that pentagonal wires should be detectable, as the only ones who can
yield a channel number between 8 and 10.

</DOC>
<DOC>
<DOCNO> 122087 </DOCNO>
RXJ 0852.0-0462: Another Nonthermal Shell-Type SNR (G266.2-1.2)


  The newly discovered supernova remnant G266.2-1.2 (RX J0852.0--0462), along
the line of sight to the Vela SNR, was observed with ASCA for 120 ks. We find
that the X-ray spectrum is featureless, and well described by a power law,
extending to three the class of shell-type SNRs dominated by nonthermal X-ray
emission. Like G347.3-0.5, this low-latitude remnant displays discrete regions
of enhanced emission along the rim as well as faint nonthermal emission from
the interior. We derive limits on the thermal content of the remnant emission,
although the presence of the Vela SNR compromises our ability to seriously
constrain a low temperature component. Limits placed on the amount of Sc-K
emission are compared with the expected flux based upon the reported 44Ti
emission from G2662.-1.2. We also report on an unresolved X-ray source
surrounded by diffuse emission near the center of the remnant. The properties
of the source are not well determined, but appear consistent with the
interpretation that the source is a neutron star surrounded by a synchrotron
nebula. Alternatively, the source may be associated with one of two stars
located within the positional error circle, but this appears somewhat unlikely.

</DOC>
<DOC>
<DOCNO> 10029 </DOCNO>
Finite temperature expectation values of local fields in the sinh-Gordon


  Sklyanin's method of separation of variables is employed in a calculation of
finite temperature expectation values. An essential element of the approach is
Baxter's $Q$-function. We propose its explicit form corresponding to the ground
state of the sinh-Gordon theory. With the method of separation of variables we
calculate the finite temperature expectation values of the exponential fields
to one-loop order of the semi-classical expansion.

</DOC>
<DOC>
<DOCNO> 102189 </DOCNO>
Vertex Algebras, Mirror Symmetry, And D-Branes: The Case Of Complex Tori


  A vertex algebra is an algebraic counterpart of a two-dimensional conformal
field theory. We give a new definition of a vertex algebra which includes
chiral algebras as a special case, but allows for fields which are neither
meromorphic nor anti-meromorphic. To any complex torus equipped with a flat
Kahler metric and a closed 2-form we associate an N=2 superconformal vertex
algebra (N=2 SCVA) in the sense of our definition. We find a criterion for two
different tori to produce isomorphic N=2 SCVA's. We show that for algebraic
tori isomorphism of N=2 SCVA's implies the equivalence of the derived
categories of coherent sheaves corresponding to the tori or their
noncommutative generalizations (Azumaya algebras over tori). We also find a
criterion for two different tori to produce N=2 SCVA's related by a mirror
morphism. If the 2-form is of type (1,1), this condition is identical to the
one proposed by Golyshev, Lunts, and Orlov, who used an entirely different
approach inspired by the Homological Mirror Symmetry Conjecture of Kontsevich.
Our results suggest that Kontsevich's conjecture must be modified: coherent
sheaves must be replaced with modules over Azumaya algebras, and the Fukaya
category must be ``twisted'' by a closed 2-form. We also describe the
implications of our results for BPS D-branes on Calabi-Yau manifolds.

</DOC>
<DOC>
<DOCNO> 8443 </DOCNO>
Incorporation of Density Matrix Wavefunctions in Monte Carlo


  We combine the Density Matrix Technique (DMRG) with Green Function Monte
Carlo (GFMC) simulations. The DMRG is most successful in 1-dimensional systems
and can only be extended to 2-dimensional systems for strips of limited width.
GFMC is not restricted to low dimensions but is limited by the efficiency of
the sampling. This limitation is crucial when the system exhibits a so-called
sign problem, which on the other hand is not a particular obstacle for the
DMRG. We show how to combine the virtues of both methods by using a DMRG
wavefunction as guiding wave function for the GFMC. This requires a special
representation of the DMRG wavefunction to make the simulations possible within
reasonable computational time. As a test case we apply the method to the
2-dimensional frustrated Heisenberg antiferromagnet. By supplementing the
branching in GFMC with Stochastic Reconfiguration (SR) we get a stable
simulation with a small variance also in the region where the fluctuations due
to minus sign problem are maximal. The sensitivity of the results to the choice
of the guiding wavefunction is extensively investigated. We analyse the model
as a function of the ratio of the next-nearest to nearest neighbor coupling
strength. We observe in the frustrated regime a pattern of the spin
correlations which is in-between dimerlike and plaquette type ordering, states
that have recently been suggested. It is a state with strong dimerization in
one direction and weaker dimerization in the perpendicular direction.

</DOC>
<DOC>
<DOCNO> 10424 </DOCNO>
Nonuniqueness of the Potentials of Spin-Density-Functional Theory


  It is shown that, contrary to widely held beliefs, the potentials of
spin-density-functional theory (SDFT) are not unique functionals of the spin
densities. Explicit examples of distinct sets of potentials with the same
ground-state densities are constructed, and general arguments that uniqueness
should not occur in SDFT and other generalized density-functional theories are
given. As a consequence, various types of applications of SDFT require
significant corrections or modifications.

</DOC>
<DOC>
<DOCNO> 83127 </DOCNO>
Smodels: A System for Answer Set Programming


  The Smodels system implements the stable model semantics for normal logic
programs. It handles a subclass of programs which contain no function symbols
and are domain-restricted but supports extensions including built-in functions
as well as cardinality and weight constraints. On top of this core engine more
involved systems can be built. As an example, we have implemented total and
partial stable model computation for disjunctive logic programs. An interesting
application method is based on answer set programming, i.e., encoding an
application problem as a set of rules so that its solutions are captured by the
stable models of the rules. Smodels has been applied to a number of areas
including planning, model checking, reachability analysis, product
configuration, dynamic constraint satisfaction, and feature interaction.

</DOC>
<DOC>
<DOCNO> 178690 </DOCNO>
Thermal and chemical equilibration of hadronic matter


  We study thermal and chemical equilibration in 'infinite' hadron matter as
well as in finite size relativistic nucleus-nucleus collisions using a BUU
cascade transport model with resonance and string degrees-of-freedom. The
'infinite' hadron matter is simulated within a cubic box employing periodic
boundary conditions. The various equilibration times depend on baryon density
and energy density and are much shorter for particles consisting of light
quarks then for particles including strangeness. For kaons and antikaons the
chemical equilibration time is found to be larger than $\simeq$ 40 fm/c for all
baryon and energy densities considered. The inclusion of continuum excitations,
i.e. hadron 'strings', leads to a limiting temperature of $T_s\simeq$ 150 MeV.

</DOC>
<DOC>
<DOCNO> 152467 </DOCNO>
An Exotic Theory of Massless Spin-Two Fields in Three Dimensions


  It is a general belief that the only possible way to consistently deform the
Pauli-Fierz action, changing also the gauge algebra, is general relativity.
Here we show that a different type of deformation exists in three dimensions if
one allows for PT non-invariant terms. The new gauge algebra is different from
that of diffeomorphisms. Furthermore, this deformation can be generalized to
the case of a collection of massless spin-two fields. In this case it describes
a consistent interaction among them.

</DOC>
<DOC>
<DOCNO> 85017 </DOCNO>
Entrainment of an inertial reference frame by an accelerated gravitating


  For the example of an accelerated shell we show that omission of the
energy-momentum tensor (EMT) of the body that causes the acceleration and the
tensions due to this acceleration can lead to a paradoxical result; Namely, the
entrainment of an inertial frame by the accelerated shell in the direction
opposite to that of the acceleration. We consider several models and
demonstrate that the correct result can be obtained only if all components of
the full EMT are adequately taken into account, and the problem statement is
physically correct.

</DOC>
<DOC>
<DOCNO> 99452 </DOCNO>
Deformations of chiral algebras and quantum cohomology of toric


  We reproduce the quantum cohomology of toric varieties (and of some
hypersurfaces in projective spaces) as the cohomology of certain vertex
algebras with differential. The deformation technique allows us to compute the
cohomology of the chiral de Rham complex over the projective space.

</DOC>
<DOC>
<DOCNO> 170211 </DOCNO>
Rapid solution of problems by nuclear-magnetic-resonance quantum


  We offer an improved method for using a nuclear-magnetic-resonance quantum
computer (NMRQC) to solve the Deutsch-Jozsa problem. Two known obstacles to the
application of the NMRQC are exponential diminishment of density-matrix
elements with the number of bits, threatening weak signal levels, and the high
cost of preparing a suitable starting state. A third obstacle is a heretofore
unnoticed restriction on measurement operators available for use by an NMRQC.
Variations on the function classes of the Deutsch-Jozsa problem are introduced,
both to extend the range of problems advantageous for quantum computation and
to escape all three obstacles to use of an NMRQC. By adapting it to one such
function class, the Deutsch-Jozsa problem is made solvable without exponential
loss of signal. The method involves an extra work bit and a polynomially more
involved Oracle; it uses the thermal-equilibrium density matrix systematically
for an arbitrary number of spins, thereby avoiding both the preparation of a
pseudopure state and temporal averaging.

</DOC>
<DOC>
<DOCNO> 101415 </DOCNO>
A discrete form of the Beckman-Quarles theorem for two-dimensional


  Let X be a real normed vector space and dim X \ge 2. Let d>0 be a fixed real
number. We prove that if x,y \in X and ||x-y||/d is a rational number then
there exists a finite set {x,y} \subseteq S(x,y) \subseteq X with the following
property: for each strictly convex Y of dimension 2 each map from S(x,y) to Y
preserving the distance d preserves the distance between x and y. It implies
that each map from X to Y that preserves the distance d is an isometry.

</DOC>
<DOC>
<DOCNO> 8559 </DOCNO>
Signatures of spin pairing in a quantum dot in the Coulomb blockade


  Coulomb blockade resonances are measured in a GaAs quantum dot in which both
shape deformations and interactions are small. The parametric evolution of the
Coulomb blockade peaks shows a pronounced pair correlation in both position and
amplitude, which is interpreted as spin pairing. As a consequence, the
nearest-neighbor distribution of peak spacings can be well approximated by a
smeared bimodal Wigner surmise, provided that interactions which go beyond the
constant interaction model are taken into account.

</DOC>
<DOC>
<DOCNO> 150734 </DOCNO>
Testing SDLCQ in 2+1 dimensions


  The SDLCQ regularization is known to explicitly preserve supersymmetry in 1+1
dimensions. To test this property in higher dimensions, we consider
supersymmetric Yang-Mills theory on R x S^1 x S^1. In particular, we choose one
of the compact directions to be light-like and another to be space-like. This
theory is totally finite, and thus we can solve for bound state wave functions
and masses numerically without renormalizing. We present the masses as
functions of the longitudinal and transverse resolutions and show that the
masses converge rapidly in both resolutions. We study the behavior of the
spectrum as a function of the coupling and find that at strong coupling there
is a stable, well-defined spectrum which we present. We discuss also the
massless spectrum and find several unphysical states that decouple at large
transverse resolution.

</DOC>
<DOC>
<DOCNO> 117284 </DOCNO>
Mechanical analogy for the wave-particle: helix on a vortex filament


  The small amplitude-to-thread ratio helical configuration of a vortex
filament in the ideal fluid behaves exactly as de Broglie wave. The
complex-valued algebra of quantum mechanics finds a simple mechanical
interpretation in terms of differential geometry of the space curve. The wave
function takes the meaning of the velocity with which the helix rotates about
the screw axis. The helices differ in type of the screw - right or left-handed.
Two kinds of the helical waves deflect in the inhomogeneous fluid vorticity
field in the same way as spin particles in the Stern-Gerlach experiment.

</DOC>
<DOC>
<DOCNO> 116933 </DOCNO>
A 3.0mev Komac/KTF RFQ Linac


  The Radio-Frequency Quadrupole (RFQ) linac that will accelerate a 20mA proton
beam from 50keV to 3MeV has been designed and is being fabricated as the first
phase, KOMAC Test Facility (KTF), of the Korea Multipurpose Accelerator Complex
(KOMAC) project at the Korea Atomic Energy Research Institute (KAERI). The
physical, engineering designs and fabrication status of the RFQ are described.

</DOC>
<DOC>
<DOCNO> 151344 </DOCNO>
Strongly coupled quantum discrete Liouville theory. I: Algebraic


  The quantum discrete Liouville model in the strongly coupled regime, 1<c<25,
is formulated as a well defined quantum mechanical problem with unitary
evolution operator. The theory is self-dual: there are two exponential fields
related by Hermitean conjugation, satisfying two discrete quantum Liouville
equations, and living in mutually commuting subalgebras of the quantum algebra
of observables.

</DOC>
<DOC>
<DOCNO> 122016 </DOCNO>
The NGC4839 group falling into the Coma cluster observed by XMM-Newton


  We present here the first analysis of the XMM Newton EPIC-MOS data of the
galaxy group around NGC4839, which lies at a projected distance to the Coma
cluster center of 1.6Mpc. In our analysis, which includes imaging,
spectro-imaging and spectroscopy we find compelling evidence for the sub group
being on its first infall onto the Coma cluster. The complex temperature
structure around NGC 4839 is consistent with simulations of galaxies falling
into a cluster environment. We see indications of a bow shock and of ram
pressure stripping around NGC4839. Furthermore our data reveal a displacement
between NGC4839 and the center of the hot gas in the group of about 300kpc.
With a simple approximation we can explain this displacement by the pressure
force originating from the infall, which acts much stronger on the group gas
than on the galaxies.

</DOC>
<DOC>
<DOCNO> 120931 </DOCNO>
The Broad-Line and Narrow-Line Regions of the LINER NGC 4579


  We report the discovery of an extremely broad H-alpha emission line in the
LINER nucleus of NGC 4579. From ground-based observations, the galaxy was
previously known to contain a Type 1 nucleus with a broad H-alpha line of FWHM
= 2300 km/s and FWZI ~ 5000 km/s. New spectra obtained with the Hubble Space
Telescope and a 0.2 arcsec-wide slit reveal an H-alpha component with FWZI ~
18,000 km/s. The line is not obviously double-peaked, but it does possess
shoulders on the red and blue sides which resemble the H-alpha profiles of
double-peaked emitters such as NGC 4203 and NGC 4450. This similarity suggests
that the very broad H-alpha profile in NGC 4579 may represent emission from an
accretion disk. Three such objects have been found recently in two HST programs
which have targeted a total of 30 galaxies, demonstrating that double-peaked or
extremely broad-line emission in LINERs must be much more common than would be
inferred from ground-based surveys. The ratio of the narrow [S II] 6716, 6731
lines shows a pronounced gradient indicating a steep rise in density toward the
nucleus. The direct detection of a density gradient within the inner arcsecond
of the narrow-line region confirms expectations from previous observations of
linewidth-critical density correlations in several LINERs.

</DOC>
<DOC>
<DOCNO> 12456 </DOCNO>
First experimental evidence of one-dimensional plasma modes in


  We have studied niobium superconducting thin wires deposited onto a
SrTiO$_{3}$ substrate. By measuring the reflection coefficient of the wires,
resonances are observed in the superconducting state in the 130 MHz to 4 GHz
range. They are interpreted as standing wave resonances of one-dimensional
plasma modes propagating along the superconducting wire. The experimental
dispersion law, $\omega$ versus $q$, presents a linear dependence over the
entire wave vector range. The modes are softened as the temperature increases
close the superconducting transition temperature. Very good agreement are
observed between our data and the dispersion relation predicted by Kulik and
Mooij and Sch\"on.

</DOC>
<DOC>
<DOCNO> 12274 </DOCNO>
s- and d-wave Symmetries in Nonadiabatic Theory of Superconductivity


  High-$T_c$ superconductors have Fermi energies $E_F$ much smaller than
conventional metals comparable to phonon frequencies. In such a situation
nonadiabatic effects are important. A generalization of Eliashberg theory in
the nonadiabatic regime has previously been shown to reproduce some anomalous
features of the high-$T_c$ superconductors as for istance the enhancement of
$T_c$ or the isotopic effects on $T_c$ and $m^*$. In this contribution we
address the issue of the symmetry of the gap in the context of nonadiabatic
superconductivity. We show that vertex corrections have a momentum structure
which favours d-wave superconductivity when forward scattering is predominant.
An additional increase of $T_c$ is also found.

</DOC>
<DOC>
<DOCNO> 71173 </DOCNO>
Order alpha^7 ln(1/alpha) Contribution to Positronium Hyperfine


  The logarithmically enhanced alpha^7 ln(1/alpha) contribution to the
hyperfine splitting of the positronium ground-state energy levels is calculated
in the framework of dimensionally regularized nonrelativistic quantum
electrodynamics. The correction is negative and amounts to about 1/3 of the
leading logarithmic alpha^7 ln^2(1/alpha) one. The discrepancy between the
experimental measurements and the theoretical prediction is reduced.

</DOC>
<DOC>
<DOCNO> 178859 </DOCNO>
The GDH sum rule for the Delta isobar: A possible anomaly?


  The GDH sum rule is discussed for the Delta(1232) resonance. It is shown that
apart from ordinary excitations to higher-energy states, the sum rule contains
a large negative contribution due to de-excitation into the nucleon state.
Therefore, a fulfillment of the sum rule assumes a strong coupling of Delta^+
and Delta^0 to resonances of spin 5/2 and higher. Calculations performed in
quark models suggest that D15(1675) may be such a resonance. However, its
strength is found to be not sufficient for bringing the GDH sum rule to a
theoretically expected positive magnitude.

</DOC>
<DOC>
<DOCNO> 10318 </DOCNO>
A Continuous Time Asynchronous Model of the Stock Market; Beyond the LLS


  In order to simulate the complex phenomena manifested in stock markets, we
introduce a continuous asynchronous model in which millions of individual
traders interact through a central orders matching mechanism, just as it
happens in real stock markets. Each trader has a unique decision function,
which allows him/ her to trade at any time, to react to external news, to
respond to price changes (or volume, volatility, etc.), and to consider the
"fundamental price". As a simple example we consider three "generic" decision
functions, which correspond to three trader profiles: Noisy, Fundamentalist and
Chartist.

</DOC>
<DOC>
<DOCNO> 178583 </DOCNO>
Double Beta Decay: Theory, Experiment, and Implications


  The theory, experimental status, and implications of double beta decay are
reviewed.

</DOC>
<DOC>
<DOCNO> 12118 </DOCNO>
An exactly solvable toy model that mimics the mode coupling theory of


  A toy model is proposed which incorporates the reversible mode coupling
mechanism responsible for ergodic-nonergodic transition with trivial
Hamiltonian in the mode coupling theory (MCT) of structural glass transition.
The model can be analyzed without relying on uncontrolled approximations
inevitable in the current MCT. The strength of hopping processes can be easily
tuned and the ideal glass transition is reproduced only in a certain range of
the strength. On the basis of the analyses of our model we discuss about a
sharp ergodic-nonergodic transition and its smearing out by "hopping".

</DOC>
<DOC>
<DOCNO> 71950 </DOCNO>
Radiative VPgamma transitions and eta-eta' mixing


  A value for the $\eta$-$\eta^\prime$ mixing angle is extracted from the data
on $VP\gamma$ transitions using simple quark-model ideas. The set of data
covers {\it all} possible radiative transitions between the pseudoscalar and
vector meson nonets. Two main ingredients of the model are the introduction of
flavour-dependent overlaps for the various $q\bar{q}$ wave functions and the
use of the quark-flavour basis to describe the $\eta$-$\eta^\prime$ system. In
this basis the mixing angle is found to be $\phi_P=(37.7\pm 2.4)^\circ$.

</DOC>
<DOC>
<DOCNO> 84651 </DOCNO>
Quantum Zeno effect and the detection of gravitomagnetism


  In this work we introduce two experimental proposals that could shed some
light upon the inertial properties of intrinsic spin. In particular we will
analyze the role that the gravitomagnetic field of the Earth could have on a
quantum system with spin 1/2. We will deduce the expression for Rabi
transitions, which depend, explicitly, on the coupling between the spin of the
quantum system and the gravitomagnetic field of the Earth. Afterwards, the
continuous measurement of the energy of the spin 1/2 system is considered, and
an expression for the emerging quantum Zeno effect is obtained. Thus, it will
be proved that gravitomagnetism, in connection with spin 1/2 systems, could
induce not only Rabi transitions but also a quantum Zeno effect.

</DOC>
<DOC>
<DOCNO> 70922 </DOCNO>
Hybrid Baryons, a brief review


  This contribution is a brief review of the status of hybrid baryons, which
are hypothetical baryons that incorporate a gluonic excitation. We first
summarize the status of hybrid mesons, since this closely related topic has
seen considerable recent activity with the identification of two exotic
candidates. Next we review theoretical expectations for the masses and quantum
numbers of hybrid baryons, which have come from studies of the bag model, QCD
sum rules and the flux tube model. Finally hybrid baryon experiment is
discussed, including suggestions for experimenters at COSY.

</DOC>
<DOC>
<DOCNO> 117111 </DOCNO>
Relativistic Quantum Physics with Hyperbolic Numbers


  The hyperbolic number system is rarely used though it is a helpful tool for
the description of relativistic physics. It allows a rewriting of the quadratic
Dirac equation in terms of a 2x2-matrix equation. In addition, the relativistic
description of spin and orbital angular momentum is simplified with the
hyperbolic number system. Beside of other applications this new developed
formalism can be used for the solution of relativistic single particle
equations with non-static potentials.

</DOC>
<DOC>
<DOCNO> 11106 </DOCNO>
Polydisperse star polymer solutions


  We analyze the effect of polydispersity in the arm number on the effective
interactions, structural correlations and the phase behavior of star polymers
in a good solvent. The effective interaction potential between two star
polymers with different arm numbers is derived using scaling theory. The
resulting expression is tested against monomer-resolved molecular dynamics
simulations. We find that the theoretical pair potential is in agreement with
the simulation data in a much wider polydispersity range than other proposed
potentials. We then use this pair potential as an input in a many-body theory
to investigate polydispersity effects on the structural correlations and the
phase diagram of dense star polymer solutions. In particular we find that a
polydispersity of 10%, which is typical in experimental samples, does not
significantly alter previous findings for the phase diagram of monodisperse
solutions.

</DOC>
<DOC>
<DOCNO> 102735 </DOCNO>
Self-dual Chern-Simons Vortices on Riemann Surfaces


  We study self-dual multi-vortex solutions of Chern-Simons Higgs theory in a
background curved spacetime. The existence and decaying property of a solution
are demonstrated.

</DOC>
<DOC>
<DOCNO> 11864 </DOCNO>
Controlling adsorbate vibrational lifetimes using superlattices


  We propose using short-period superlattices as substrates to control the
vibrational relaxation dynamics of adsorbate overlayers. The mass modulation of
superlattices creates both band gaps and large spectral enhancements in the
phonon density of states. These modifications can dramatically alter the
coupling between vibrational modes of the adsorbate overlayer and the substrate
lattice, thereby significantly affecting the lifetime of adsorbate modes.

</DOC>
<DOC>
<DOCNO> 69843 </DOCNO>
Displaced Vertices in Extended Supersymmetric Models


  In extended supersymmetric models with additional singlet Higgs fields
displaced vertices could be observed if the decay width of the next-to-lightest
supersymmetric particle becomes very small due to a singlino dominated LSP. We
study the supersymmetric parameter space where displaced vertices of the second
lightest neutralino exist in the NMSSM and an E6 inspired model. For a mass
difference between LSP and NLSP of more than 10 GeV the singlet vacuum
expectation value has to be at least of the order of 100 TeV in order to obtain
a lightest neutralino with a singlino component large enough for displaced
vertices.

</DOC>
<DOC>
<DOCNO> 120785 </DOCNO>
The Nuclear Star Cluster of the Milky Way: Star Formation, Dynamics and


  High spatial resolution, near-infrared imaging and spectroscopy of the
nuclear star cluster have given key new insights about the dynamics, evolution
and mass distribution in the Milky Way Center. The central parsec is powered by
a cluster of hot, massive stars which must have formed a few million years ago.
Either star formation was triggered in the central parsec by the infall of a
very dense cloud, or a dense, young star cluster formed outside of the central
parsec sank rapidly into the nuclear region through dynamical friction. The
presence of luminous asymptotic giant branch (AGB) stars suggests that there
were earlier such star formation episodes. Measurements of radial and proper
motions for more than 200 stars delineate the stellar dynamics to a scale of a
few light days from the dynamic center which is coincident with the compact
radio source (SgrA*) within ~0.1" (800 AU). The stellar velocities increase
toward SgrA* with a Kepler law (to >1000 km/s for the innermost stars),
implying the presence of a three million solar mass central (dark) mass. The
observations make a compelling case that this mass concentration is a black
hole which is currently accreting at a low rate or radiating at low efficiency.
With the exception of the young, massive stars the velocity field of the
central stellar cluster is close to isotropic. The young stars are
characterized by a turbulent rotation pattern that still carries the imprint of
the angular momentum distribution in the original cloud or star cluster.

</DOC>
<DOC>
<DOCNO> 12631 </DOCNO>
Control of Coherent Acoustic Phonons


  Using sub-picosecond optical pump-probe techniques, coherent zone-folded
longitudinal acoustic phonons (ZFLAPs) were generated and controlled in an
InGaN multiple quantum well structure. A one-pump, one-probe differential
transmission technique revealed that carriers injected near the barrier band
edge were quickly captured into the quantum wells and generated strong coherent
ZFLAP oscillations. Two-pump differential transmission was used to generate and
control coherent ZFLAP oscillations through the relative timing and amplitude
of the two pump pulses. Enhancement and suppression of ZFLAP oscillations were
demonstrated, including complete cancellation of generated acoustic phonons for
the first time in any material system. Coherent control was used to demonstrate
that ZFLAPs are generated differently in InGaN multiple quantum wells than in
GaAs/AlAs superlattices.

</DOC>
<DOC>
<DOCNO> 150760 </DOCNO>
On non-$L^2$ solutions to the Seiberg-Witten equations


  We show that a previous paper of Freund describing a solution to the
Seiberg-Witten equations has a sign error rendering it a solution to a related
but different set of equations. The non-$L^2$ nature of Freund's solution is
discussed and clarified and we also construct a whole class of solutions to the
Seiberg-Witten equations.

</DOC>
<DOC>
<DOCNO> 11841 </DOCNO>
Ferromagnetic Polarons in Manganites


  Using the Lanczos method in linear chains we study the double exchange model
in the low concentration limit, including an antiferromagnetic super-exchange
K. In the strong coupling limit we find that the ground state contains
ferromagnetic polarons whose length is very sensitive to the value of K/t. We
investigate the dispersion relation, the trapping by impurities, and the
interaction between these polarons. As the overlap between polarons increases,
by decreasing K/t, the effective interaction between them changes from
antiferromagnetic to ferromagnetic. The scaling to the thermodynamic limit
suggests an attractive interaction in the strong coupling regime (J_h > t) and
no binding in the weak limit (J_h \simeq t).

</DOC>
<DOC>
<DOCNO> 116940 </DOCNO>
The FaBrE Project at Trieste


  A program to design a high brilliance electron source suitable for a short
wavelength Linac-based FEL is presented. The goal of the project is to develop
a multi-cell integrated photoinjector capable of delivering 1 nC bunches with
emittance below 1 mm mrad. This will be the first step toward a possible
development of a IV generation light source test facility based on the existing
Trieste Linac. For this purpose a common program between Sincrotrone Trieste
and INFN-Milano has been undertaken. Here a brief description of the program
and the first results of the RF Gun electromagnetic structure with the beam
dynamics on the ELETTRA Linac are presented.

</DOC>
<DOC>
<DOCNO> 8845 </DOCNO>
Breakdown of the standard Perturbation Theory and Moving Boundary


  The derivation of a Moving Boundary Approximation or of the response of a
coherent structure like a front, vortex or pulse to external forces and noise,
is generally valid under two conditions: the existence of a separation of time
scales of the dynamics on the inner and outer scale and the existence and
convergence of solvability type integrals. We point out that these conditions
are not satisfied for pulled fronts propagating into an unstable state: their
relaxation on the inner scale is power law like and in conjunction with this,
solvability integrals diverge. The physical origin of this is traced to the
fact that the important dynamics of pulled fronts occurs in the leading edge of
the front rather than in the nonlinear internal front region itself. As recent
work on the relaxation and stochastic behavior of pulled fronts suggests, when
such fronts are coupled to other fields or to noise, the dynamical behavior is
often qualitatively different from the standard case in which fronts between
two (meta)stable states or pushed fronts propagating into an unstable state are
considered.

</DOC>
<DOC>
<DOCNO> 83251 </DOCNO>
3-Coloring in Time O(1.3289^n)


  We consider worst case time bounds for NP-complete problems including 3-SAT,
3-coloring, 3-edge-coloring, and 3-list-coloring. Our algorithms are based on a
constraint satisfaction (CSP) formulation of these problems. 3-SAT is
equivalent to (2,3)-CSP while the other problems above are special cases of
(3,2)-CSP; there is also a natural duality transformation from (a,b)-CSP to
(b,a)-CSP. We give a fast algorithm for (3,2)-CSP and use it to improve the
time bounds for solving the other problems listed above. Our techniques involve
a mixture of Davis-Putnam-style backtracking with more sophisticated matching
and network flow based ideas.

</DOC>
<DOC>
<DOCNO> 101954 </DOCNO>
The tensor Dirac equation in Riemannian space


  We suggest a tensor equation on Riemannian manifolds which can be considered
as a generalization of the Dirac equation for the electron. The tetrad
formalism is not used. Also we suggest a new form of the tensor Dirac equation
with a Spin(1,3) gauge symmetry in Minkowski space.

</DOC>
<DOC>
<DOCNO> 152601 </DOCNO>
Partial spontaneous breaking of two-dimensional supersymmetry


  We construct low-energy Goldstone superfield actions describing various
patterns of the partial spontaneous breakdown of two-dimensional N=(1,1),
N=(2,0) and N=(2,2) supersymmetries, with the main focus on the last case.
These nonlinear actions admit a representation in the superspace of the
unbroken supersymmetry as well as in a superspace of the full supersymmetry.
The natural setup for implementing the partial breaking in a self-consistent
way is provided by the appropriate central extensions of D=2 supersymmetries,
with the central charges generating shift symmetries on the Goldstone
superfields. The Goldstone superfield actions can be interpreted as manifestly
world-sheet supersymmetric actions in the static gauge of some superstrings and
D1-branes in D=3 and D=4 Minkowski spaces. As an essentially new example, we
elaborate on the action representing the 1/4 partial breaking pattern N=(2,2)
-> N=(1,0).

</DOC>
<DOC>
<DOCNO> 80668 </DOCNO>
Universality of the Axial Anomaly in Lattice QCD


  We prove that lattice QCD generates the axial anomaly in the continuum limit
under very general conditions on the lattice action, which includes the case of
Ginsparg-Wilson fermions. The ingredients going into the proof are gauge
invariance, locality of the Dirac operator, absence of fermion doubling, the
general form of the lattice Ward identity, and the power counting theorem of
Reisz. The results generalize in an obvious way to SU(N) lattice gauge
theories.

</DOC>
<DOC>
<DOCNO> 100667 </DOCNO>
The Dirac operator of a commuting d-tuple


  Given a commuting d-tuple $\bar T=(T_1,...,T_d)$ of otherwise arbitrary
nonnormal operators on a Hilbert space, there is an associated Dirac operator
$D_{\bar T}$. Significant attributes of the d-tuple are best expressed in terms
of $D_{\bar T}$, including the Taylor spectrum and the notion of Fredholmness.
  In fact, {\it all} properties of $\bar T$ derive from its Dirac operator. We
introduce a general notion of Dirac operator (in dimension $d=1,2,...$) that is
appropriate for multivariable operator theory. We show that every abstract
Dirac operator is associated with a commuting $d$-tuple, and that two Dirac
operators are isomorphic iff their associated operator $d$-tuples are unitarily
equivalent.
  By relating the curvature invariant introduced in a previous paper to the
index of a Dirac operator, we establish a stability result for the curvature
invariant for pure d-contractions of finite rank. It is shown that for the
subcategory of all such $\bar T$ which are a) Fredholm and and b) graded, the
curvature invariant $K(\bar T)$ is stable under compact perturbations. We do
not know if this stability persists when $\bar T$ is Fredholm but ungraded,
though there is concrete evidence that it does.

</DOC>
<DOC>
<DOCNO> 70855 </DOCNO>
Infrared Consistency of NSVZ and DRED Supersymmetric Gluodynamics


  Pade approximant methods are applied to known terms of the DRED beta-
function for N = 1 supersymmetric SU(3) Yang-Mills theory. Each of the [N|M]
approximants with N + M less than or equal to 4 (M not equal to zero)
constructed from this series exhibits a positive pole which precedes any zeros
of the approximant, consistent with the same infrared-attractor pole behaviour
known to characterise the exact NSVZ beta-function. A similar Pade-approximant
analysis of truncations of the NSVZ series is shown consistently to reproduce
the geometric-series pole of the exact NSVZ beta function.

</DOC>
<DOC>
<DOCNO> 116725 </DOCNO>
Slow inviscid flows of a compressible fluid in spatially inhomogeneous


  An ideal compressible fluid is considered, with an equilibrium density being
a given function of coordinates due to presence of some static external forces.
The slow flows in such system, which do not disturb the density, are
investigated with the help of the Hamiltonian formalism. The equations of
motion of the system are derived for an arbitrary given topology of the
vorticity field. The general form of the Lagrangian for frozen-in vortex lines
is established. The local induction approximation for motion of slender vortex
filaments in several inhomogeneous physical models is studied.

</DOC>
<DOC>
<DOCNO> 150557 </DOCNO>
On the chiral and deconfinement phase transitions in parity-conserving


  We present some results about the interplay between the chiral and
deconfinement phase transitions in parity-conserving QED3 (with N flavours of
massless 4 component fermions) at finite temperature. Following Grignani et al
(Phys. Rev. D53, 7157 (1996), Nucl. Phys. B473, 143 (1996)), confinement is
discussed in terms of an effective Sine-Gordon theory for the timelike
component of the gauge field A_0. But whereas in the references above the
fermion mass m is a Lagrangian parameter, we consider the m=0 case and ask
whether an effective S-G theory can again be derived with m replaced by the
dynamically generated mass Sigma which appears below T_{ch}, the critical
temperature for the chiral phase transition. The fermion and gauge sectors are
strongly interdependent, but as a first approximation we decouple them by
taking Sigma to be a constant, depending only on the constant part of the gauge
field. We argue that the existence of a low-temperature confining phase may be
associated with the generation of Sigma; and that, analogously, the vanishing
of Sigma for T > T_{ch} drives the system to its deconfining phase. The effect
of the gauge field dynamics on mass generation is also indicated. (38kb)

</DOC>
<DOC>
<DOCNO> 39728 </DOCNO>
The Q^2 Dependence of Dijet Cross Sections in gamma p Interactions at


  The dependence of the photon structure on the photon virtuality, Q^2, is
studied by measuring the reaction e^+p\to e^+ + {\rm jet} + {\rm jet} + {\rm X}
at photon-proton centre-of-mass energies 134 < W < 223 GeV. Events have been
selected in the Q^2 ranges \approx 0 GeV^2, 0.1-0.55 GeV^2, and 1.5-4.5 GeV^2,
having two jets with transverse energy E_T^{jet} > 5.5 GeV in the final state.
The dijet cross section has been measured as a function of the fractional
momentum of the photon participating in the hard process, x_gamma. The ratio of
the dijet cross section with x_gamma < 0.75 to that with x_gamma > 0.75
decreases as Q^2 increases. The data are compared with the predictions of NLO
pQCD and leading-order Monte Carlo programs using various parton distribution
functions of the photon. The measurements can be interpreted in terms of a
resolved photon component that falls with Q^2 but remains present at values of
Q^2 up to 4.5 GeV^2. However, none of the models considered gives a good
description of the data.

</DOC>
<DOC>
<DOCNO> 150745 </DOCNO>
Consistent SO(6) Reduction Of Type IIB Supergravity on S^5


  Type IIB supergravity can be consistently truncated to the metric and the
self-dual 5-form. We obtain the complete non-linear Kaluza-Klein S^5 reduction
Ansatz for this theory, giving rise to gravity coupled to the fifteen
Yang-Mills gauge fields of SO(6) and the twenty scalars of the coset
SL(6,R)/SO(6). This provides a consistent embedding of this subsector of N=8,
D=5 gauged supergravity in type IIB in D=10. We demonstrate that the
self-duality of the 5-form plays a crucial role in the consistency of the
reduction. We also discuss certain necessary conditions for a theory of gravity
and an antisymmetric tensor in an arbitrary dimension D to admit a consistent
sphere reduction, keeping all the massless fields. We find that it is only
possible for D=11, with a 4-form field, and D=10, with a 5-form. Furthermore,
in D=11 the full bosonic structure of eleven-dimensional supergravity is
required, while in D=10 the 5-form must be self-dual. It is remarkable that
just from the consistency requirement alone one would discover D=11 and type
IIB supergravities, and that D=11 is an upper bound on the dimension.

</DOC>
<DOC>
<DOCNO> 102215 </DOCNO>
Real algebraic curves, the moment map and amoebas


  In this paper we prove the topological uniqueness of maximal arrangements of
a real plane algebraic curve with respect to three lines. More generally, we
prove the topological uniqueness of a maximally arranged algebraic curve on a
real toric surface. We use the moment map as a tool for studying the topology
of real algebraic curves and their complexifications.

</DOC>
<DOC>
<DOCNO> 100340 </DOCNO>
On Well-behaved Unbounded Representations of *-Algebras


  A general approach to the well-behaved unbounded *-representations of a
*-algebra X is proposed. Let B be a normed *-algebra equipped with a left
action |> of X on B such that (x |> a)^+ b=a^+(x^+ |> b) for a,b\in B and x\in
X. Then the pair (X,B) is called a compatible pair. For any continuous
non-degenerate *-representation \rho of B there exists a closed
*-representation \rho' of X such that \rho'(x)\rho(b)=\rho(x |> b), where x\in
X and b\in B. The *-representations \rho' are called the well-behaved
*-representations associated with the compatible pair (X,B). A number of
examples are developed in detail.

</DOC>
<DOC>
<DOCNO> 14036 </DOCNO>
Inhomogeneous superconducting state in quasi-one-dimensional systems


  We report on results of theoretical study of non-uniform superconducting
states in quasi-one-dimensional systems, with attractive interactions and
Zeeman splitting between electron spins. Using bosonization to treat intrachain
electron-electron interactions, and a combination of renormalization group and
mean-field approximation to tackle interchain couplings, we obtain the phase
diagram of the system, and show that the transition between the uniform and
non-uniform superconducting phases is a continuous transition of the
commensurate-incommensurate type.

</DOC>
<DOC>
<DOCNO> 120571 </DOCNO>
HST Observations of the Interacting Galaxies NGC 2207 and IC 2163


  Hubble Space Telescope images of the galaxies NGC 2207 and IC 2163 show star
formation and dust structures in a system that has experienced a recent grazing
encounter. Tidal forces from NGC 2207 compressed and elongated the disk of IC
2163, forming an oval ridge of star formation. Gas flowing away from this ridge
has thin parallel dust filaments transverse to the direction of motion.
Numerical models suggest that the filaments come from flocculent spiral arms
that were present before the interaction. A dust lane at the outer edge of the
tidal tail is a shock front where the flow abruptly changes direction. A spiral
arm of NGC 2207 that is backlit by IC 2163 is seen to contain several parallel,
knotty filaments that are probably shock fronts in a density wave. Blue
clusters of star formation inside these dust lanes show density wave triggering
by local gravitational collapse. Spiral arms inside the oval of IC 2163 could
be the result of ILR-related orbits in the tidal potential that formed the
oval. Their presence suggests that tidal forces alone may initiate a temporary
nuclear gas flow and eventual starburst without first forming a stellar bar.
Several emission structures resembling jets 100-1000 pc long appear. There is a
dense dark cloud with a conical shape 400 pc long and a bright compact cluster
at the tip, and with a conical emission nebula of the same length that points
away from the cluster in the other direction. This region coincides with a
non-thermal radio continuum source that is 1000 times the luminosity of Cas A
at 20 cm.

</DOC>
<DOC>
<DOCNO> 70216 </DOCNO>
Probing R-violating top quark decays at hadron colliders


  We examine the possibility of observing exotic top quark decays via
R-violating SUSY interactions at the Fermilab Tevatron and CERN LHC. We present
cross-sections for $t\bar t$ production followed by the subsequent decay of
either $t$ or $\bar t$ via the R-violating interaction while the other
undergoes the SM decay. With suitable kinematic cuts, we find that the exotic
decays can possibly be detected over standard model backgrounds at the future
runs of the Tevatron and LHC, but not at Run 1 of the Tevatron due to limited
statistics. Discovery limits for R-Violating couplings in the top sector are
presented.

</DOC>
<DOC>
<DOCNO> 12885 </DOCNO>
Macroscopic and Local Magnetic Moments in Si-doped CuGeO$_3$ with


  The temperature-concentration phase diagram of the Si-doped spin-Peierls
compound CuGeO$_{3}$ is investigated by means of neutron scattering and muon
spin rotation spectroscopy in order to determine the microscopic distribution
of the magnetic and lattice dimerised regions as a function of doping. The
analysis of the zero-field muon spectra has confirmed the spatial inhomogeneity
of the staggered magnetisation that characterises the antiferromagnetic
superlattice peaks observed with neutrons. In addition, the variation of the
macroscopic order parameter with doping can be understood by considering the
evolution of the local magnetic moment as well as of the various regions
contributing to the muon signal.

</DOC>
<DOC>
<DOCNO> 68518 </DOCNO>
Positive strangeness contribution to the nucleon magnetic moment in a


  The strangeness contribution to the nucleon magnetic moment is calculated at
the one-loop level in a relativistic SU(3) chiral potential model and is found
to be {\em positive}, that is, with an {\em opposite} sign to the nucleon
strangeness polarization. It is the ``Z'' diagram that violates the usual
relation between spin and magnetic moment. The positive value is due to the
contribution from the intermediate excited quark states, while the intermediate
ground state gives a negative contribution. Our numerical results agree quite
well with the new measurement of the SAMPLE Collaboration.

</DOC>
<DOC>
<DOCNO> 68393 </DOCNO>
Soft partons production in deep inelastic kinematics


  It is argued considering multiple production in the deep inelastic scattering
kinematics that the very high multiplicity events are extremely sensitive to
the low-x partons density.

</DOC>
<DOC>
<DOCNO> 121460 </DOCNO>
Constraints on Inflation


  A short introduction to structure formation is given, followed by a
discussion of the possible characteristics of the initial perturbations
assuming a generic inflationary origin. Observational data related to
large-scale structure and the cosmic microwave background radiation is then
used in an attempt to constrain the characteristics of such perturbations.
Future directions are also explored.
  The possibility of direct detection of a stochastic gravitational wave
background produced during an inflationary phase in the early Universe is
briefly discussed, as well as the available evidence regarding the present
value of the total energy density in the Universe.

</DOC>
<DOC>
<DOCNO> 69025 </DOCNO>
Higgs boson decay to mu mubar gamma


  The Higgs boson decay, H -> mu mubar gamma, is studied in the Standard Model
at the tree and one-loop levels. It is shown that for Higgs boson masses above
110 GeV, the contribution to the radiative width from the one-loop level
exceeds the contribution from the tree level, and for Higgs boson masses above
140 GeV, it even exceeds the contribution from the tree level decay H -> mu
mubar. We also show that the contributions to the radiative decay width from
the interference terms between the tree and one-loop diagrams are negligible.

</DOC>
<DOC>
<DOCNO> 68963 </DOCNO>
R-parity Violating Contribution to Neutron EDM at One-loop Order


  We present the full result for the down squark mass-squared matrix in the
complete theory of supersymmetry without R-parity where all kind of R-parity
violating terms are admitted without bias. An optimal parametrization, the
single-VEV parametrization, is used. The major result is a new contribution to
$LR$ squark mixing, involving both bilinear and trilinear R-parity violating
couplings. Among other things, the latter leads to neutron electric dipole
moment at one-loop level. Similiar mechanism leading to electron electric
dipole moment at the same level. We present here a short report on major
features of neutron electric dipole moment from supersymmetry without R-parity
and give the interesting constraints obtained.

</DOC>
<DOC>
<DOCNO> 68781 </DOCNO>
Natural Chaotic Inflation in Supergravity


  We propose a chaotic inflation model in supergravity. In the model the
K\"ahler potential has a Nambu-Goldstone-like shift symmetry of the inflaton
chiral multiplet which ensures the flatness of the inflaton potential beyond
the Planck scale. We show that the chaotic inflation naturally takes place by
introducing a small breaking term of the shift symmetry in the superpotential.
This may open a new branch of model building for inflationary universe in the
framework of supergravity.

</DOC>
<DOC>
<DOCNO> 151601 </DOCNO>
Noncommutative Geometry, Negative Probabilities and Cantorian-Fractal


  A straightforward explanation of the Young's two-slit experiment of a quantum
particle is obtained within the framework of the Noncommutative Geometric
associated with El Naschie's Cantorian-Fractal transfinite Spacetime continuum.

</DOC>
<DOC>
<DOCNO> 9978 </DOCNO>
Changing shapes in the nanoworld


  What are the mechanisms leading to the shape relaxation of three dimensional
crystallites ? Kinetic Monte Carlo simulations of fcc clusters show that the
usual theories of equilibration, via atomic surface diffusion driven by
curvature, are verified only at high temperatures. Below the roughening
temperature, the relaxation is much slower, kinetics being governed by the
nucleation of a critical germ on a facet. We show that the energy barrier for
this step linearly increases with the size of the crystallite, leading to an
exponential dependence of the relaxation time.

</DOC>
<DOC>
<DOCNO> 100435 </DOCNO>
Resolution of singularities of null cones


  We give canonical resolutions of singularities of several cone varieties
arising from invariant theory. We establish a connection between our
resolutions and resolutions of singularities of closure of conjugacy classes in
classical Lie algebras.

</DOC>
<DOC>
<DOCNO> 9733 </DOCNO>
Energy Dependence of Quasi-Particle Relaxation in a Disordered Fermi


  A spectroscopic method is applied to measure the inelastic quasi-particle
relaxation rate in a disordered Fermi liquid. The quasi-particle relaxation
rate, $\gamma$ is deduced from the magnitude of fluctuations in the local
density of states, which are probed using resonant tunneling through a
localized impurity state. We study its dependence on the excitation energy $E$
measured from the Fermi level. In a disordered metal (heavily doped GaAs) we
find $\gamma \propto E^{3/2}$ within the experimentally accessible energy
interval, in agreement with the Altshuler-Aronov theory for electron-electron
interactions in diffusive conductors.

</DOC>
<DOC>
<DOCNO> 9594 </DOCNO>
Nucleation on top of islands in epitaxial growth


  We develop a theory for nucleation on top of islands in epitaxial growth
based on the derivation of lifetimes and rates governing individual microscopic
processes. These processes are strongly affected by the additional step edge
barrier E_S for descending atoms. If the dissociation times of unstable
clusters can be neglected, the theory predicts that for small critical nuclei
of size i<=2 the nucleation is governed by fluctuations, during which by chance
i+1 atoms are present on the island. For large critical nuclei i>=3 by
contrast, the nucleation process can be described in a mean-field type manner,
which for large E_S corresponds to the approach developed by Tersoff et al.
[Phys. Rev. Lett. 72, 266 (1994)]. In both the fluctuation-dominated and the
mean-field case, various scaling regimes are identified, where the typical
island size at the onset of nucleation shows a power law in dependence on the
adatom diffusion rates, the incoming atom flux, and the step edge crossing
probability exp(-E_S/k_B T). For the case where the dissociation rates of
metastable clusters enter the problem as additional parameters, we set up a
semi-analytical approach based on novel rate equations, which can easily be
solved numerically. The results obtained from the theory are in good agreement
with Monte Carlo data. Implications for various applications are pointed out.

</DOC>
<DOC>
<DOCNO> 71094 </DOCNO>
The t->WZb decay in the Standard Model: A Critical Reanalysis


  We compute the t->WZb decay rate, in the Standard Model, at the leading order
in perturbation theory, with special attention to the effects of the finite
widths of the W and Z bosons. These effects are extremely important, since the
t->WZb decay occurs near its kinematical threshold. They increase the value of
the decay rate by orders of magnitude near threshold or allow it below the
nominal threshold. We discuss a procedure to take into account the finite-width
effects and compare the results with previous studies of this decay. Within the
Standard Model, for a top quark mass in the range between 170 and 180 GeV, we
find BR(t->WZb) ~ 2 x 10^{-6}, which makes the observation at the LHC very
difficult if at all possible.

</DOC>
<DOC>
<DOCNO> 8693 </DOCNO>
Mechanism of spin-triplet superconductivity in Sr2RuO4


  The unique Fermi surfaces and their nesting properties of Sr2RuO4 are
considered. The existence of unconventional superconductivity is shown
microscopically, for the first time, from the magnetic interactions (due to
nesting) and the phonon-mediated interactions. The odd-parity superconductivity
is favored in the $\alpha$ and $\beta$ sheets of the Fermi surface, and the
various superconductivities are possible in the $\gamma$ sheet. There are a
number of possible odd-parity gaps, which include the gaps with nodes, the
breaking of time-reversal symmetry and $\vec{d}\parallel \hat{z}$.

</DOC>
<DOC>
<DOCNO> 85065 </DOCNO>
Effective equations in quantum cosmology


  We develop a general framework for effective equations of expectation values
in quantum cosmology and pose for them the quantum Cauchy problem with
no-boundary and tunneling wavefunctions. Cosmological configuration space is
decomposed into two sectors that give qualitatively different contributions to
the radiation currents in effective equations. The field-theoretical sector of
inhomogeneous modes is treated by the method of Euclidean effective action,
while the quantum mechanical sector of the spatially homogeneous inflaton is
handled by the technique of manifest quantum reduction to gauge invariant
cosmological perturbations. We apply this framework in the model with a big
negative non-minimal coupling, which incorporates a recently proposed low
energy (GUT scale) mechanism of the quantum origin of the inflationary Universe
and study the effects of the quantum inflaton mode.

</DOC>
<DOC>
<DOCNO> 120049 </DOCNO>
The HST Survey of BL~Lacertae Objects. IV. Infrared Imaging of Host


  The HST NICMOS Camera 2 was used for H-band imaging of 12 BL Lacertae objects
taken from the larger sample observed with the WFPC2 in the R band (Urry et al.
2000; Scarpa et al. 2000). Ten of the 12 BL Lacs are clearly resolved, and the
detected host galaxies are large, bright ellipticals with average H-band
absolute magnitude M=-26.2+-0.45 mag and effective radius 10+-5 kpc. The
rest-frame integrated color of the host galaxies is on average R-H=2.3+-0.3,
consistent with the value for both radio galaxies and normal, non-active
elliptical galaxies, and indicating the dominant stellar population is old. The
host galaxies tend to be bluer in their outer regions than in their cores, with
average color gradient Delta(R-H)/Delta(log r)=-0.2 mag, again consistent with
results for normal non-active elliptical galaxies. The infrared Kormendy
relation, derived for the first time for BL Lac host galaxies, is m(e) =
3.8*log(R)+14.8 (where m(e) is the surface brightness at the effective radius
R), fully in agreement with the relation for normal ellipticals. The close
similarity between BL Lac host galaxies and normal ellipticals suggests the
active nucleus has surprisingly little effect on the host galaxy. This supports
a picture in which all elliptical galaxies harbor black holes which can be
actively accreting for some fraction of their lifetime.

</DOC>
<DOC>
<DOCNO> 121722 </DOCNO>
Liquid Xenon for a Very Sensitive WIMP Search


  We describe the research and development efforts of the UCLA Torino group to
develop a large, powerful, discriminating WIMP detector. We also discuss the
possible amplifications of the WIMP signal. The first real detector, ZEPLIN II,
is being prepared for the UKDMC Boulby Mine Laboratory.

</DOC>
<DOC>
<DOCNO> 117063 </DOCNO>
Local Momentum and a Three-Body Gauge


  In recent years researchers have attempted to improve the continuum state
three-body wavefunction for three, mutually interacting Coulomb particles by
including, so called, local momentum effects, which depend upon the logarithmic
gradient of the continuum, two-body Coulomb waves. Using the exact three-body
wavefunction in the region where two of the three particles remain close, a
revised description of these local momenta, is attained which predicts that a
quantum-mechanical impulse may develop in the reaction zone, causing
like-sign-charged particles to decrease their radial separation and
opposite-sign-charged particles to increase their radial separation. The
consequences of these predictions are investigated through both quantum and
semi-classical techniques where the total energy of a two-body continuum
Coulomb system in the presence of a third, mutually interacting body are
analyzed. Numerical calculations confirm that while ignoring these local
effects for light-ion-atom processes, may be appropriate, three-body effects
may dominate in the reaction zone for heavy-ion-atom processes. This hypothesis
is investigated and it is shown that a real-valued, position-dependent phase is
added to the wavefunction. Further analysis shows that one may detect
asymptotic variations in the scattering amplitudes for massive systems at
near-threshold energies. These results provide convincing theoretical and
physical evidence for a formal three-body gauge.

</DOC>
<DOC>
<DOCNO> 68581 </DOCNO>
Searching for Lorentz Violation in the Ground State of Hydrogen


  A theoretical analysis is made of experiments in hydrogen and antihydrogen
that test CPT. We show that these experiments also provide sensitive tests of
Lorentz symmetry for protons and electrons. Both 1S-2S transitions and Zeeman
hyperfine splittings in the ground state are examined. We find that sensitivity
to CPT and Lorentz violation at the level of $10^{-27}$ GeV is attainable.

</DOC>
<DOC>
<DOCNO> 170512 </DOCNO>
On the partial wave amplitude of Coulomb scattering in three dimensions


  The partial wave series for the Coulomb scattering amplitude in three
dimensions is evaluated in a very simple way to give the closed result.

</DOC>
<DOC>
<DOCNO> 69109 </DOCNO>
Extracting and using photon polarization information in radiative B


  We discuss the uses of conversion electron pairs for extracting photon
polarization information in weak radiative B decays. Both cases of leptons
produced through a virtual and real photon are considered. Measurements of the
angular correlation between the $(K\pi)$ and $(e^+e^-)$ decay planes in $B\to
K^*(\to K\pi)\gamma^{(*)}(\to e^+e^-)$ decays can be used to determine the
helicity amplitudes in the radiative $B\to K^*\gamma$ decay. A large
right-handed helicity amplitude in $\bar B$ decays is a signal of new physics.
The time-dependent CP asymmetry in the $B^0$ decay angular correlation is shown
to measure $\sin 2\beta$ and $\cos 2\beta$ with little hadronic uncertainty.

</DOC>
<DOC>
<DOCNO> 11386 </DOCNO>
n(k) Structure and Matrix Elements in Photoemission: Results from


  The photon energy dependence of angle-resolved photoemission data on
Ca_2CuO_2Cl_2 is presented, and the role of the matrix element is investigated.
It is shown that despite strong variations in the matrix element, the loss in
intensity as one crosses the antiferromagnetic zone boundary is a robust
feature of the Mott insulator. As expected for a two dimensional system, the
dispersion remains independent of the photon energy even when the matrix
element does not.

</DOC>
<DOC>
<DOCNO> 179017 </DOCNO>
In-medium spin-orbit NN potential in the Skyrme model


  It is considered how spin-orbit potential for two nucleons is changed when
one of them is imbedded in nuclear matter. It is emphasized that there appears
new tipe of potential antisymmetric under nucleon spins which is proportional
to mass difference between free and imbedded nucleons. The longest range
behaviour of such potential is estimated.

</DOC>
<DOC>
<DOCNO> 68109 </DOCNO>
Lambda Polarization in Polarized Proton-Proton Collisions at RHIC


  We discuss Lambda polarization in semi-inclusive proton-proton collisions,
with one of the protons longitudinally polarized. The hyperfine interaction
responsible for the $\Delta$-$N$ and $\Sigma$-$\Lambda$ mass splittings gives
rise to flavor asymmetric fragmentation functions and to sizable polarized
non-strange fragmentation functions. We predict large positive Lambda
polarization in polarized proton-proton collisions at large rapidities of the
produced Lambda, while other models, based on SU(3) flavor symmetric
fragmentation functions, predict zero or negative Lambda polarization. The
effect of $\Sigma^0$ and $\Sigma^*$ decays is also discussed. Forthcoming
experiments at RHIC will be able to differentiate between these predictions.

</DOC>
<DOC>
<DOCNO> 11395 </DOCNO>
Application of the generalized 3D Jordan-Wigner transformation to the


  We extend the definition of the Jordan-Wigner transformation to three
dimensions using the generalization of ideas that were used in the
two-dimensional case by one of the present authors. Under this transformation,
the 3D XY Hamiltonian is transformed into a system of spinless fermions coupled
to a gauge field with only two components. We calculate the flux per plaquette
for the 3 elementary perpendicular plaquettes of a cubic lattice, and find that
it is nonzero for only two of the plaquettes. We provide a simple
interpretation for the average phase-per-plaquette being $\pi$ on the
plaquettes where it is nonzero. Then we apply these findings to the
investigation of the Heisenberg bilayer antiferromagnet.

</DOC>
<DOC>
<DOCNO> 40404 </DOCNO>
Signals for Non-Commutative Interactions at Linear Colliders


  Recent theoretical results have demonstrated that non-commutative geometries
naturally appear within the context of string/M-theory. One consequence of this
possibility is that QED takes on a non-abelian nature due to the introduction
of 3- and 4-point functions. In addition, each QED vertex acquires a momentum
dependent phase factor. We parameterize the effects of non-commutative
space-time co-ordinates and show that they lead to observable signatures in
several $2\to 2$ QED processes in $e^+e^-$ collisions. In particular, we
examine pair annihilation, Moller and Bhabha scattering, as well as
$\gamma\gamma\to\gamma\gamma$ scattering and show that non-commutative scales
of order a TeV can be probed at high energy linear colliders.

</DOC>
<DOC>
<DOCNO> 122437 </DOCNO>
Database of Geneva stellar evolution tracks and isochrones for


  We have used an updated version of the empirically and semi-empirically
calibrated BaSeL library of synthetic stellar spectra of Lejeune et al. (1997,
1998) and Westera et al. (1999) to calculate synthetic photometry in the
UBVRIJHKLL'M, HST-WFPC2, Geneva, and Washington systems for the entire set of
non-rotating Geneva stellar evolution models covering masses from 0.4-0.8 to
120-150 Msun and metallicities Z=0.0004 (1/50 Zsun) to 0.1 (5 Zsun). The
results are provided in a database which includes all individual stellar tracks
and the corresponding isochrones covering ages from 10^3 yr to 16--20 Gyr in
time steps of Delta(log t)= 0.05 dex. The database also includes a new grid of
stellar tracks of very metal-poor stars (Z=0.0004) from 0.8 - 150 Msun
calculated with the Geneva stellar evolution code.
  The full database will be available in electronic form at the CDS
(http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/(vol)/(page)) and at
http://webast.ast.obs-mip.fr/stellar/.

</DOC>
<DOC>
<DOCNO> 150883 </DOCNO>
Higher Dimensional Schwinger-like Anomalous Effective Action


  We construct explicit form of the anomalous effective action, in arbitrary
even dimension, for Abelian vector and axial gauge fields coupled to Dirac
fermions. It turns out to be a surprisingly simple extension of 2D Schwinger
model effective action.

</DOC>
<DOC>
<DOCNO> 10391 </DOCNO>
A critical examination of the spin dynamics in high-$T_C$ cuprates


  A critical examination of the spin dynamics in high-$T_C$ cuprates is made on
the light of inelastic neutron scattering results obtained by different groups.
Recent neutron data show that incommensurate magnetic peaks in YBCO belong to
the same excitation as the resonance peak observed at $(\pi/a,\pi/a)$. Being
only observed in the superconducting state, the incommensurability is then
rather difficult to reconcile with a stripe picture. We also discuss the link
between the resonance peak spectral weight and the superconducting condensation
energy.

</DOC>
<DOC>
<DOCNO> 9873 </DOCNO>
Transition between Compressible and Incompressible States in


  Possible phase transitions between incompressible quantum Hall states and
compressible three-dimensional states are discussed for infinite-layer electron
systems in strong magnetic field. By variational Monte Carlo calculation,
relative stability of some trial states is studied. If the inter-layer distance
is large enough, the Laughlin state is stabilized for the Landau-level filling
\nu=1/3 of each layer. When the inter-layer distance is comparable to the
magnetic length, the Laughlin state becomes unstable against a different
fractional quantum Hall state with inter-layer correlation, and/or against a
three-dimensional compressible state. It is discussed how the quantum phase
transition between them can be controlled in actual systems.

</DOC>
<DOC>
<DOCNO> 8060 </DOCNO>
Magnon dispersions in quantum Heisenberg ferrimagnetic chains at zero


  Within the Dyson-Maleev boson formalism, we study the zero-temperature magnon
dispersions in a family of one-dimensional quantum Heisenberg ferrimagnets
composed of two different spins $(S_1,S_2)$ in the elementary cell. It is shown
that the spin-wave theory can produce precise quantitative results for the
low-energy excitations. The spin-stiffness constant $\rho_s$ and the optical
magnon gap $\Delta$ of different $(S_1,S_2)$ ferrimagnetic systems are
calculated, respectively, to second and third order in the quasiparticle
interaction. The spin-wave results are compared with available numerical
estimates.

</DOC>
<DOC>
<DOCNO> 11761 </DOCNO>
Segregation transitions in wet granular matter


  We report the effect of interstitial fluid on the extent of segregation by
imaging the pile that results after bidisperse color-coded particles are poured
into a silo. Segregation is sharply reduced and preferential clumping of small
particles is observed when a small volume fraction of fluid $V_f$ is added. We
find that viscous forces in addition to capillary forces have an important
effect on the extent of segregation $s$ and the angle of repose $\theta$. We
show that the sharp initial change and the subsequent saturation in $s$ and
$\theta$ occurs over similar $V_f$. We also find that a transition back to
segregation can occur when the particles are completely immersed in a fluid at
low viscosities.

</DOC>
<DOC>
<DOCNO> 99648 </DOCNO>
Fock representations of the superalgebra sl(n+1|m), its quantum analogue


  Fock space representations of the Lie superalgebra $sl(n+1|m)$ and of its
quantum analogue $U_q[sl(n+1|m)]$ are written down. The results are based on a
description of these superalgebras via creation and annihilation operators. The
properties of the underlying statistics are shortly discussed.

</DOC>
<DOC>
<DOCNO> 9676 </DOCNO>
Piezoelectric mechanism of orientation of stripe structures in


  A piezoelectric mechanism of orientation of stripes in two-dimensional
quantum Hall systems in GaAs heterostructures is considered. The anisotropy of
the elastic moduli and the boundary of the sample are taken into account. It is
found that in the average the stripes line up with the [110] axis. In double
layer systems the wave vector of the stripe structure rotates from the [110] to
[100] axis if the period of density modulation becomes large than the
interlayer distance. From the experimental point of view it means that in
double layer systems anisotropic part of resistivity changes its sign under
variation of the external magnetic field.

</DOC>
<DOC>
<DOCNO> 68256 </DOCNO>
Implications of the Unitarity Triangle `uc' for J, $\delta$ and


  The Jarlskog rephasing invariant parameter $|J|$ is evaluated using one of
the six Unitarity Triangles involving well known CKM matrix elements \vud,
\vus,~\rub, ~\vcd, ~\vcs~ and ~\vcb. With PDG2000 values of \vud~ etc. as
input, we obtain $|J|=(2.71 \pm 1.12) \times 10^{-5}$, which in the PDG
representation of CKM matrix leads to the range $21^o~to~159^o$ for the CP
violating phase $\delta$. The CKM matrix elements evaluated using this range of
$\delta$ are in agreement with the PDG CKM matrix. The implications of
refinements in the input on $|J|$, $\delta$ and CKM matrix elements have also
been studied.

</DOC>
<DOC>
<DOCNO> 9219 </DOCNO>
A Stochastic Cascade Model for FX Dynamics


  A time series model for the FX dynamics is presented which takes into account
structural peculiarities of the market, namely its heterogeneity and an
information flow from long to short time horizons. The model emerges from an
analogy between FX dynamics and hydrodynamic turbulence. The heterogeneity of
the market is modeled in form of a multiplicative cascade of time scales
ranging from several minutes to a few months, analogous to the Kolmogorov
cascade in turbulence.
 The model reproduces well the important empirical characteristics of FX rates
for major currencies, as the heavy-tailed distribution of returns, their change
in shape with increasing time interval, and the persistence of volatility.

</DOC>
<DOC>
<DOCNO> 116360 </DOCNO>
The Equilibrium Distribution of Gas Molecules Adsorbed on an Active


  We evaluate the exact equilibrium distribution of gas molecules adsorbed on
an active surface with an infinite number of attachment sites. Our result is a
Poisson distribution having mean $X = {\mu P P_s \over P_e}$, with $\mu$ the
mean gas density, $ P_s$ the sticking probability, $P_e$ the evaporation
probability in a time interval $\tau$, and $P$ Smoluchowski's exit probability
in time interval $\tau$ for the surface in question. We then solve for the case
of a finite number of attachment sites using the mean field approximation,
recovering in this case the Langmuir isotherm.

</DOC>
<DOC>
<DOCNO> 121809 </DOCNO>
The Physics of Blazar Optical Emission Regions II: Magnetic Field


  For a sample of 51 blazars with extensive optical polarization data, we used
circular statistics to calculate the scatter among the polarization position
angles for each object. We found that this scatter is correlated with the radio
core dominance. We compared this relationship with the predictions of a simple
transverse shock model. The result suggests that blazar jets are likely to
cover a wide range of speeds consistent with those derived from observations of
superluminal motion.

</DOC>
<DOC>
<DOCNO> 9458 </DOCNO>
Collective Phenomena in Defect Crystals


  We investigate effects of interactions between substitutional defects on the
properties of defect crystals at low temperatures, where defect motion is
governed by quantum effects. Both, thermal and dynamical properties are
considered. The influence of interactions on defect motion is described via a
collective effect. Our treatment is semiclassical in the sense that we analyze
collective effects in a classical setting, and analyze the influence on
quantized defect motion only thereafter. Our theory describes a crossover to
glassy behavior at sufficiently high defect concentration. Our approach is
meant to be general. For the sake of definiteness, we evaluate most of our
results with parameters appropriate for Li-doped KCl crystals.

</DOC>
<DOC>
<DOCNO> 80612 </DOCNO>
Quasi-asymptotic freedom in the two dimensional O(3) model


  The behaviour of the renormalized spin 2-point function in the O(3) and
dodecahedron spin model are investigated numerically. The Monte Carlo data show
excellent agreement between the two models. The short distance behavior comes
very close to standard theoretical expectations, yet it differs significantly
from it. A possible explanation of this situation is offered.

</DOC>
<DOC>
<DOCNO> 99461 </DOCNO>
On the derived functor analogy in the Cuntz-Quillen framework for cyclic


  Cuntz and Quillen have shown that for algebras over a field $k$ with
$char(k)=0$, periodic cyclic homology may be regarded, in some sense, as the
derived functor of (non-commutative) de Rham (co-)homology. The purpose of this
paper is to formalize this derived functor analogy. We show that the
localization ${Def}^{-1}\Cal{PA}$ of the category $\Cal{PA}$ of countable
pro-algebras at the class of (infinitesimal) deformations exists (in any
characteristic) (Theorem 3.2) and that, in characteristic zero, periodic cyclic
homology is the derived functor of de Rham cohomology with respect to this
localization (Corollary 5.4). We also compute the derived functor of rational
$K$-theory for algebras over $\Bbb Q$, which we show is essentially the fiber
of the Chern character to negative cyclic homology (Theorem 6.2).

</DOC>
<DOC>
<DOCNO> 13365 </DOCNO>
Polyelectrolyte Adsorption


  The problem of charged polymer chains (polyelectrolytes) as they adsorb on a
planar surface is addressed theoretically. We review the basic mechanisms and
theory underlying polyelectrolyte adsorption on a single surface in two
situations: adsorption of a single charged chain, and adsorption from a bulk
solution in $\theta$ solvent conditions. The behavior of flexible and
semi-rigid chains is discussed separately and is expressed as function of the
polymer and surface charges, ionic strength of the solution and polymer bulk
concentration. We mainly review mean-field results and briefly comment about
fluctuation effects. The phenomenon of polyelectrolyte adsorption on a planar
surface as presented here is of relevance to the stabilization of colloidal
suspensions. In this respect we also mention calculations of the inter-plate
force between two planar surfaces in presence of polyelectrolyte. Finally, we
comment on the problem of charge overcompensation and its implication to
multi-layers formation of alternating positive and negative polyelectrolytes on
planar surfaces and colloidal particles.

</DOC>
<DOC>
<DOCNO> 117335 </DOCNO>
Analytical Estimation of the Beam-Beam Interaction Limited Dynamic


  Physically speaking, the delta function like beam-beam nonlinear forces at
interaction points (IPs) act as a sum of delta function nonlinear multipoles.
By applying the general theory established in ref. 1, in this paper we
investigate analytically the beam-beam interaction limited dynamic apertures
and the corresponding beam lifetimes for both the round and the flat beams.
Relations between the beam-beam limited beam lifetimes and the beam-beam tune
shifts are established, which show clearly why experimentally one has always a
maximum beam-beam tune shift, \xi_{y, max}, around 0.045 for e-^+e$^- circular
colliders, and why one can use round beams to double this value approximately.
Comparisons with some machine parameters are given. Finally, we discuss the
mechanism of the luminosity reduction due to a definite collision crossing
angle.

</DOC>
<DOC>
<DOCNO> 9320 </DOCNO>
Analysis of Oscillator Neural Networks for Sparsely Coded Phase Patterns


  We study a simple extended model of oscillator neural networks capable of
storing sparsely coded phase patterns, in which information is encoded both in
the mean firing rate and in the timing of spikes. Applying the methods of
statistical neurodynamics to our model, we theoretically investigate the
model's associative memory capability by evaluating its maximum storage
capacities and deriving its basins of attraction. It is shown that, as in the
Hopfield model, the storage capacity diverges as the activity level decreases.
We consider various practically and theoretically important cases. For example,
it is revealed that a dynamically adjusted threshold mechanism enhances the
retrieval ability of the associative memory. It is also found that, under
suitable conditions, the network can recall patterns even in the case that
patterns with different activity levels are stored at the same time. In
addition, we examine the robustness with respect to damage of the synaptic
connections. The validity of these theoretical results is confirmed by
reasonable agreement with numerical simulations.

</DOC>
<DOC>
<DOCNO> 118239 </DOCNO>
Patterns of Super Star Cluster Formation in `Clumpy' Starburst Galaxies


  We present preliminary results from a Hubble Space Telescope (HST) WFPC2
investigation of spatial and temporal distributions of star clusters in the
clumpy irregular galaxy NGC 7673 and the starburst spirals NGC 3310 and Haro 1.
We compare the spectral energy distributions of star clusters in the large
clumps in NGC 7673 to model calculations of stellar clusters of various ages.
We also propose that the presence of super star clusters in clumps seems to be
a feature of intense starbursts.

</DOC>
<DOC>
<DOCNO> 120613 </DOCNO>
The luminosity dependence of clustering and higher order correlations in


  We investigate the spatial clustering of galaxies in the PSCz galaxy redshift
survey, as revealed by the two-point correlation function, the luminosity mark
correlations, and the moments of counts-in-cells. We construct volume-limited
subsamples at different depths, and search for a luminosity dependence of the
clustering pattern. We find no statistically significant effect in either the
two-point correlation function or the mark correlations and so we take each
subsample (of different characteristic luminosity) as representing the same
statistical process. We then carry out a counts-in-cells analysis of the
volume-limited subsamples, including a rigorous error calculation based on the
recent theory of Szapudi, Colombi and Bernardeau. In this way, we derive the
best estimates to date of the skewness and kurtosis of IRAS galaxies in
redshift space. Our results agree well with previous measurements in both the
parent angular catalogue, and in the derived redshift surveys. This is in
contrast with smaller, optically selected surveys, were there is a discrepancy
between the redshift space and projected measurements. Predictions from cold
dark matter theory, obtained using the recent semi-analytical model of galaxy
formation of Benson {\it et al}, provide an excellent description of our
clustering data.

</DOC>
<DOC>
<DOCNO> 70787 </DOCNO>
Correlated Scattering and Cluster Planes


  We suggest a new correlation in diffractive production of 2 ``clusters''
$A+B\to A^\ast B^\ast$ with large intrinsic angular momenta for each $A^\ast$
and $B^\ast$ cluster. These correlations are expected in the context of the
``color dipole picture'' for high energy collision and reflect the approximate
conservation of dipole direction during the collision. This conservation is in
particular manifest when the two dipoles, $\vec d_A$, $\vec d_B$ and the impact
vector $\undtilb$ are all parallel. The predicted positive triple correlation
is between the momentum transfer $\undtildel$ and the planes of the $A^\ast$
and $B^\ast$ clusters.

</DOC>
<DOC>
<DOCNO> 13270 </DOCNO>
Mott-Hubbard Metal-Insulator Transition in Paramagnetic V_2O_3: a


  The electronic properties of paramagnetic V_2O_3 are investigated by the
ab-initio computational scheme LDA+DMFT(QMC). This approach merges the local
density approximation (LDA) with dynamical mean-field theory (DMFT) and uses
numerically exact quantum Monte Carlo simulations (QMC) to solve the effective
Anderson impurity model of DMFT. Starting with the crystal structure of
metallic V_2O_3 and insulating (V_{0.962}Cr_{0.038})_2O_3 we find a
Mott-Hubbard metal-insulator-like transition at a Coulomb interaction U\approx
5eV. The calculated spectrum is in very good agreement with experiment.
Furthermore, the occupation of the (a_{1g},e_{g1}^{\pi},e_{g2}^{\pi}) orbitals
and the spin state S=1 determined by us agree with recent polarization
dependent X-ray-absorption experiments.

</DOC>
<DOC>
<DOCNO> 101871 </DOCNO>
Introductory Calculus from the Viewpoint of Non-Standard Analysis -


  This article exemplifies a novel approach to the teaching of introductory
differential calculus using the modern notion of ``infinitesimal'' as opposed
to the traditional approach using the notion of ``limit''. I illustrate the
power of the new approach with a discussion of the derivatives of the sine and
cosine functions.

</DOC>
<DOC>
<DOCNO> 99334 </DOCNO>
On finite order variational sequences


  We discuss intrinsic aspects of Krupka's approach to finite-order variational
sequences. We give intrinsic isomorphisms of the quotient subsheaves of the
short finite-order variational sequence with sheaves of forms on jet spaces of
suitable order, obtaining a new finite-order (short exact) variational sequence
which is made by sheaves of polynomial differential operators. Moreover, we
present an intrinsic formulation for the Helmholtz condition of local
variationality using a technique introduced by Kolar that we have adapted to
our context. Finally, we provide the minimal order solution to the inverse
problem of the calculus of variations and a solution of the problem of the
variationally trivial Lagrangian.

</DOC>
<DOC>
<DOCNO> 83331 </DOCNO>
Quantum Algorithms for Weighing Matrices and Quadratic Residues


  In this article we investigate how we can employ the structure of
combinatorial objects like Hadamard matrices and weighing matrices to device
new quantum algorithms. We show how the properties of a weighing matrix can be
used to construct a problem for which the quantum query complexity is
ignificantly lower than the classical one. It is pointed out that this scheme
captures both Bernstein & Vazirani's inner-product protocol, as well as
Grover's search algorithm.
  In the second part of the article we consider Paley's construction of
Hadamard matrices, which relies on the properties of quadratic characters over
finite fields. We design a query problem that uses the Legendre symbol chi
(which indicates if an element of a finite field F_q is a quadratic residue or
not). It is shown how for a shifted Legendre function f_s(i)=chi(i+s), the
unknown s in F_q can be obtained exactly with only two quantum calls to f_s.
This is in sharp contrast with the observation that any classical,
probabilistic procedure requires more than log(q) + log((1-e)/2) queries to
solve the same problem.

</DOC>
<DOC>
<DOCNO> 12109 </DOCNO>
On heat flow and non-reciprocity


  Heat transfer properties in non-reciprocal systems are discussed. An ideal
experiment employing microwave or optical isolators is considered in order to
investigate the possibility for a spontaneous transfer of energy between two
black bodies at common temperatures. Under the validity of the adopted
assumptions on the examined physical system, the effect appears to be weak but
feasible.

</DOC>
<DOC>
<DOCNO> 151702 </DOCNO>
Giant Gravitons, BPS bounds and Noncommutativity


  It has been recently suggested that gravitons moving in $AdS_m \times S^n$
spacetimes along the $S^n$ blow up into spherical $(n-2)$ branes whose radius
increases with increasing angular momentum. This leads to an upper bound on the
angular momentum, thus ``explaining'' the stringy exclusion principle. We show
that this bound is present only for states which saturate a BPS-like condition
involving the energy $E$ and angular momentum $J$, $E \geq J/R$, where $R$ is
the radius of $S^n$. Restriction of motion to such states lead to a
noncommutativity of the coordinates on $S^n$. As an example of motions which do
not obey the exclusion principle bound, we show that there are finite action
instanton configurations interpolating between two possible BPS states. We
suggest that this is consistent with the proposal that there is an effective
description in terms of supergravity defined on noncommutative spaces and
noncommutativity arises here because of imposing supersymmetry.

</DOC>
<DOC>
<DOCNO> 11064 </DOCNO>
Comment on "Antilocalization in a 2D Electron Gas in a Random Magnetic


  In a recent Letter, Taras-Semchuk and Efetov reconsider the problem of
electron localization in a random magnetic field in two dimensions. They claim
that due to the long-range nature of the vector potential correlations an
additional term appears in the effective field theory ($\sigma$-model) of the
problem, leading to delocalization at the one-loop level. This calls into
question the results of earlier analytical studies, where the random magnetic
field problem was mapped onto the conventional unitary-class $\sigma$-model,
implying that the leading quantum correction is of two-loop order and of a
localizing nature. We show in this Comment, however, that the new term in fact
does not exist and was erroneously obtained by Taras-Semchuk and Efetov because
of an inconsistent treatment violating gauge invariance.

</DOC>
<DOC>
<DOCNO> 118538 </DOCNO>
X-ray emitting-absorbing media in Seyfert 1 galaxies


  Seyfert galaxies have been shown to exhibit a large variety of features in
their X-ray spectra from which the environment of the central engine can be
deduced. We focus on the two following aspects: the Warm Absorber, mainly
responsible of the soft X-ray properties, and the reprocessing/reflecting
plasma medium at the origin of the iron Kalpha fluorescent line. The physical
parameters and the location of the so-called Warm Absorber (WA), a photoionized
medium along the line of sight to the nuclear region, are more strongly
constrained by optical coronal lines than by the oxygen edges observed in the
soft X-rays and produced by the WA. The photoionization models also predict the
intensities of the X-ray emission lines which are going to be detected with the
new generation of X-ray satellites. An alternative model to the relativistic
accretion disc is proposed to explain the profile of the X-ray iron Kalpha line
observed in the Seyfert 1. This line can be formed in the framework of a
quasi-spherical accretion of optically thick clouds. An optically thick
photoionization code coupled with a Monte-Carlo code has been developed to
compute the entire spectrum from the IR to the hard X-rays for a close geometry
with a large covering factor. The multiple Compton reflections allow to
reproduce the redshifted broad iron line as detected in several Seyfert 1
galaxies and in MCG-6-30-15.

</DOC>
<DOC>
<DOCNO> 10228 </DOCNO>
Limit Theorems for Height Fluctuations in a Class of Discrete Space and


  We introduce a class of one-dimensional discrete space-discrete time
stochastic growth models described by a height function $h_t(x)$ with corner
initialization. We prove, with one exception, that the limiting distribution
function of $h_t(x)$ (suitably centered and normalized) equals a Fredholm
determinant previously encountered in random matrix theory. In particular, in
the universal regime of large $x$ and large $t$ the limiting distribution is
the Fredholm determinant with Airy kernel. In the exceptional case, called the
critical regime, the limiting distribution seems not to have previously
occurred. The proofs use the dual RSK algorithm, Gessel's theorem, the
Borodin-Okounkov identity and a novel, rigorous saddle point analysis. In the
fixed $x$, large $t$ regime, we find a Brownian motion representation. This
model is equivalent to the Sepp\"al\"ainen-Johansson model. Hence some of our
results are not new, but the proofs are.

</DOC>
<DOC>
<DOCNO> 122014 </DOCNO>
On the Local Separation of E and B Polarization Patterns in CMBR


  The work examines the small-scale E and B patterns of the CMBR polarization
anisotropy. Particularly we address the topological natures and spatial
symmetries of the E and B modes, and how one may make use of the local
measurements of Stokes parameters to separate these two modes. The analysis of
a local map in the Fourier space for separating the E and B modes can be an
ill-defined problem, due to the non-periodic boundary condition in the map for
each mode. A strategy for the E-B separation in a local map can be through an
appropriate projection of the polarization tensor field into a unique vector
field, which naturally contains a curl-free E component and a divergence-free B
component. An integral method, equivalent to the real-space, top-hat filtering,
is proposed for extracting the smoothed "charge" and "current" of the E and B
modes separately. The top-hat filter function exhibits, in its power spectrum,
an oscillation of a well-defined frequency comparable to the filter size. It is
pointed out that when the inverse filter size is chosen properly, matching the
oscillation period in the E-mode power spectrum, the sensitivity for the E-mode
detection can be made to be significantly improved.

</DOC>
<DOC>
<DOCNO> 67804 </DOCNO>
Equivalence of Recurrence Relations for Feynman Integrals with the Same


  We show that the problem of solving recurrence relations for L-loop
(R+1)-point Feynman integrals within the method of integration by parts is
equivalent to the corresponding problem for (L+R)-loop vacuum or (L+R-1)-loop
propagator-type integrals. Using this property we solve recurrence relations
for two-loop massless vertex diagrams, with arbitrary numerators and integer
powers of propagators in the case when two legs are on the light cone, by
reducing the problem to the well-known solution of the corresponding recurrence
relations for massless three-loop propagator diagrams with specific boundary
conditions.

</DOC>
<DOC>
<DOCNO> 121327 </DOCNO>
X-Ray Bursters A1742-294 and SLX1744-299/300 Near the Galactic Center


  We present a study of two X-ray bursters in the Galactic Center field with
the ART-P telescope onboard GRANAT. During 1990-1992 approximately 100 X-ray
bursts were detected from the Galactic Center field and most of them were
identified with the two persistent sources, A1742-294 and SLX1744-299/300. The
burst recurrence times were found to be ~2.4 and ~4.6 hours, respectively,
which is significantly shorter them was previously thought. We calculated the
mean and maximum fluxes during the bursts and investigated their time profiles.
We found that the shape of A1742-294 bursts correlates with the burst peak
flux. The spectral analysis was carried out for the strongest burst, detected
from A1742-294 on Oct 18, 1990.

</DOC>
<DOC>
<DOCNO> 122035 </DOCNO>
Measurement of the magnetic field direction in the NGC2024-FIR5


  Molecular outflows from young protostars are widely believed to be collimated
by magnetic fields, but there has been little observational evidence to support
this hypothesis. Using the new technique of millimetre-wavelength
spectro-polarimetry, we demonstrate the existence of a magnetic field in the
NGC2024-FIR5 outflow lobe. The 1.3mm J=2-1 transition of carbon monoxide (CO)
is polarized at a level of approximately 1%, in a direction within 10-15
degrees of the outflow axis. This agrees with theoretical models where the
magnetic field channels the outflowing gas, and shows that the process can be
effective as far as 0.1pc from the protostar.

</DOC>
<DOC>
<DOCNO> 9246 </DOCNO>
Mesoscopic Stoner Instability


  The paper is devoted to the magnetic properties of isolated mesoscopic
grains. We demonstrate that under very general conditions the electron -
electron interactions in such grains can be taken into account by a simple
interaction Hamiltonian. This Hamiltonian involves only three coupling
constants which correspond to charging, exchange interaction, and
superconducting correlations. The most important condition for such a
description is that Thouless conductance of each grain is large. Under this
condition sample-to-sample fluctuations of the coupling constants can be
neglected. However, the thermodynamic properties can still remain
sample-specific due to the one-electron part of the Hamiltonian. If the grain
is made from a material which is close to the threshold of ferromagnetic
instability the mesoscopic fluctuations of the magnetization are especially
strong. Moreover, the situation becomes multi-stable: free energy of each grain
as a function of the magnetization is characterized by a large number of local
minima. We analyze the statistics of these minima and show that it possesses
simple scaling properties. Numerical simulations confirm this scaling.

</DOC>
<DOC>
<DOCNO> 121394 </DOCNO>
An RXTE Survey of Long-Term X-ray Variability in Seyfert 1 Galaxies


  Data from the first three years of RXTE observations have been systematically
analyzed to yield a set of 300 day, 2-10 keV light curves with similarly
uniform, ~5 day sampling, for a total of nine Seyfert 1 galaxies. This is the
first X-ray variability survey to consistently probe time scales longer than a
few days in a large number of AGN. Comparison with ASCA data covering a similar
band but much shorter (~1 day) time scales shows that all the AGN are more
strongly variable on long time scales than on short time scales. This increase
is greatest for the highest-luminosity sources. The well-known anticorrelation
between source luminosity and variability amplitude is both stronger and
shallower in power-law slope when measured on long time scales. This is
consistent with a picture in which the X-ray variability of Seyfert 1s can be
can be described by a single, universal fluctuation power density shape for
which the cutoff moves to longer time scales for higher luminosity sources. All
of the Seyfert 1s exhibit stronger variability in the relatively soft 2-4 keV
band than in the harder 7-10 keV band. This effect is much too pronounced to be
explained by simple models based on either the dilution of the power-law
continuum by the Compton reflection component or on the hard X-rays being
produced in a static, pair-dominated, plane-parallel Comptonizing corona.

</DOC>
<DOC>
<DOCNO> 116997 </DOCNO>
Compression of High-Charge Electron Bunches


  The A0 Photoinjector at Fermilab can produce high charge (10-14 nC) electron
bunches of low emittance (20 pi mm-mrad for 12 nC). We have undertaken a study
of the optimal compression conditions. Off-crest acceleration in the 9-cell
capture cavity induces an energy-time correlation, which is rotated by the
compressor chicane (4 dipoles). The bunch length is measured using streak
camera images of optical transition radiation. We present measurements under
various conditions, including the effect of the laser pulse length (2 ps sigma
Gaussian vs. 10 ps FWHM flat top). The best compression to date is for a 13.2
nC bunch with sigma = 0.63 mm (1.89 ps), which corresponds to a peak current of
2.8 kA.

</DOC>
<DOC>
<DOCNO> 117421 </DOCNO>
HST NICMOS Observation of Proto-Planetary Nebulae


  We report NICMOS wide-band and polarimetric observations of four
proto-planetary nebulae. Molecular hydrogen emission is detected near the ends
of the bipolar lobes of IRAS 17150-3224, which is evidence for the interaction
of a fast, collimated outflow with the remnant of the asymptotic giant branch
wind.

</DOC>
<DOC>
<DOCNO> 8802 </DOCNO>
Visualizing the particle-hole dualism in high-temperature


  Recent Scanning Tunneling Microscope (STM) experiments offer a unique insight
into the inner workings of the superconducting state of high-Tc
superconductors. Deliberately placed inside the material impurities perturb the
coherent state and produce additional excitations. Superconducting excitations
- quasiparticles - are the quantum mechanical mixture of negatively charged
electron (-e) and positively charged hole (+e). Depending on the applied
voltage bias in STM one can sample the particle and hole content of a
superconducting excitation. We argue that the complimentary cross-shaped
patterns observed on the positive and negative biases are the manifestation of
the particle-hole dualism of the quasiparticles.

</DOC>
<DOC>
<DOCNO> 11922 </DOCNO>
Ferromagnetism in the Periodic Anderson Model: A Comparison of Spectral


  We compare different approximation schemes for investigating ferromagnetism
in the periodic Anderson model. The use of several approximations allows for a
detailed analysis of the implications of the respective methods, and also of
the mechanisms driving the ferromagnetic transition. For the Kondo limit, our
results confirm a previously proposed mechanism leading to ferromagnetic order,
namely an RKKY exchange mediated via the formation of Kondo screening clouds in
the conduction band. The contrary case is found in the intermediate-valence
regime. Here, the bandshift correction ensuring a correct high-energy expansion
of the self-energy is essential. Inclusion of damping effects reduces stability
of the ferromagnetic phase.

</DOC>
<DOC>
<DOCNO> 10819 </DOCNO>
Enhancement of tunneling from a correlated 2D electron system by a


  We consider the effect of electron correlations on tunneling from a 2D
electron layer in a magnetic field parallel to the layer. A tunneling electron
can exchange its momentum with other electrons, which leads to an exponential
increase of the tunneling rate compared to the single-electron approximation.
Explicit results are obtained for a Wigner crystal. They provide a qualitative
and quantitative explanation of the data on electrons on helium. We also
discuss tunneling in semiconductor heterostructures.

</DOC>
<DOC>
<DOCNO> 100831 </DOCNO>
A Note on Planar and Dismantlable Lattices


  It is shown that any finite, rank-connected, dismantlable lattice is
lexicographically shellable (hence Cohen-Macaulay). A ranked,
interval-connected lattice is shown to be rank-connected, but a rank-connected
lattice need not be interval-connected. An example of a planar, rank-connected
lattice that is not admissible is given.

</DOC>
<DOC>
<DOCNO> 170769 </DOCNO>
The Chirality of Exceptional Points


  Exceptional points are singularities of the spectrum and wave functions which
occur in connection with level repulsion. They are accessible in experiments
using dissipative systems. It is shown that the wave function at an exceptional
point is one specific superposition of two wave functions which are themselves
specified by the exceptional point. The phase relation of this superposition
brings about a chirality which should be detectable in an experiment.

</DOC>
<DOC>
<DOCNO> 70459 </DOCNO>
Transverse Muon Polarization in $K^{\pm}\to\pi^0\mu^{\pm}\nu$ Decay


  We calculate the transverse muon polarization in the decay
$K^{\pm}\to\pi^0\mu^{\pm}\nu$ induced by the electromagnetic two-photon
final-state interaction. For the central part of the Dalitz plot the typical
value of this polarization is about $4\times 10^{-6}$.

</DOC>
<DOC>
<DOCNO> 100276 </DOCNO>
The Dunford-Pettis property on tensor products


  We show that, in some cases, the projective and the injective tensor products
of two Banach spaces do not have the Dunford-Pettis property (DPP). As a
consequence, we obtain that $(c_0\hat{\otimes}_\pi c_0)^{**}$ fails the DPP.
Since $(c_0\hat{\otimes}_\pi c_0)^{*}$ does enjoy it, this provides a new space
with the DPP whose dual fails to have it. We also prove that, if $E$ and $F$
are ${\mathscr L}_1$-spaces, then $E\hat{\otimes}_\epsilon F$ has the DPP if
and only if both $E$ and $F$ have the Schur property. Other results and
examples are given.

</DOC>
<DOC>
<DOCNO> 70993 </DOCNO>
Single chargino production at linear colliders


  We study the single chargino production $e^+ e^- \to \tilde \chi^{\pm}
\mu^{\mp}$ at linear colliders which occurs through the $\l_{121}$ R-parity
violating coupling constant. We focus on the final state containing 4 leptons
and some missing energy. The largest background is \susyq and can be reduced
using the initial beam polarization and some cuts based on the specific
kinematics of the single chargino production. Assuming the highest allowed
supersymmetric background, a center of mass energy of $\sqrt s=500GeV$ and a
luminosity of ${\cal L}=500fb^{-1}$, the sensitivities on the $\l_{121}$
coupling constant obtained from the single chargino production study improve
the low-energy experimental limit over a range of $\Delta m_{\tilde \nu}
\approx 500GeV$ around the sneutrino resonance, and reach values of $\sim
10^{-4}$ at the $\tilde \nu$ pole. The single chargino production also allows
to reconstruct the $\tilde \chi_1^{\pm}$, $\tilde \chi_2^{\pm}$ and $\tilde
\nu$ masses. The initial state radiation plays a fundamental role in this
study.

</DOC>
<DOC>
<DOCNO> 85294 </DOCNO>
Uniformly accelerating black holes in a de Sitter universe


  A class of exact solutions of Einstein's equations is analysed which
describes uniformly accelerating charged black holes in an asymptotically de
Sitter universe. This is a generalisation of the C-metric which includes a
cosmological constant. The physical interpretation of the solutions is
facilitated by the introduction of a new coordinate system for de Sitter space
which is adapted to accelerating observers in this background. The solutions
considered reduce to this form of the de Sitter metric when the mass and charge
of the black holes vanish.

</DOC>
<DOC>
<DOCNO> 123124 </DOCNO>
Physical conditions in QSO absorbers from fine-structure absorption


  We calculate theoretical population ratios of the ground fine-structure
levels of some atoms/ions which typically exhibit UV lines in the spectra of
QSO absorbers redward the Ly-alpha forest: C0, C+, O0, Si+ and Fe+. The most
reliable atomic data available is employed and a variety of excitation
mechanisms considered: collisions with several particles in the medium, direct
excitation by photons from the cosmic microwave background radiation (CMBR) and
fluorescence induced by a UV field present.
  The theoretical population ratios are confronted with the corresponding
column density ratios of C I and C II lines observed in damped Ly-alpha (DLA)
and Lyman Limit (LL) systems collected in the recent literature to infer their
physical conditions.
  The volumetric density of neutral hydrogen in DLA systems is constrained to
be lower than tens of cm^-3 (or a few cm^-3 in the best cases) and the UV
radiation field intensity must be lower than two orders of magnitude the
radiation field of the Galaxy (one order of magnitude in the best cases). Their
characteristic sizes are higher than a few pc (tens of pc in the best cases)
and lower limits for their total masses vary from 10^0 to 10^5 solar masses.
  For the only LL system in our sample, the electronic density is constrained
to be n_e<0.15 cm^-3. We suggest that the fine-structure lines may be used to
discriminate between the current accepted picture of the UV extragalatic
background as the source of ionization in these systems against a local origin
for the ionizing radiation as supported by some authors.
  We also investigate the validity of the temperature-redshift relation of the
CMBR predicted by the standard model and study the case for alternative models.

</DOC>
<DOC>
<DOCNO> 85500 </DOCNO>
Group Averaging and Refined Algebraic Quantization: Where are we now?


  Refined Algebraic Quantization and Group Averaging are powerful methods for
quantizing constrained systems. They give constructive algorithms for
generating observables and the physical inner product. This work outlines the
current status of these ideas with an eye toward quantum gravity. The main goal
is provide a description of outstanding problems and possible research topics
in the field.

</DOC>
<DOC>
<DOCNO> 40029 </DOCNO>
Search for Lepton Flavor Violation in $K^+$ Decays


  A search for lepton flavor violating decays, \kmmp, \keep, \kpem, \kmep and
\pizem, was performed using the data collected in E865 at the Brookhaven
Alternating Gradient Synchrotron. No signal was found in any of the decay
modes. At the 90% confidence level, the branching ratios are less than
$3.0\times10^{-9}$, $6.4\times10^{-10}$, $5.2\times10^{-10}$,
$5.0\times10^{-10}$ and $3.4\times10^{-9}$ respectively.

</DOC>
<DOC>
<DOCNO> 69668 </DOCNO>
Singly charged higgses at linear collider


  We consider the production of singly charged Higgs bosons in the Higgs
triplet and two Higgs doublet models. We evaluate the cross sections for the
pair production and the single production of charged higgses at linear
collider. The decay modes of $H^+$ and the Standard Model backgrounds are
considered. We analyze the possibilities to differentiate between triplet and
two Higgs doublet models.

</DOC>
<DOC>
<DOCNO> 101578 </DOCNO>
The meromorphic non-integrability of the planar three-body problem


  We study the planar three-body problem and prove the absence of a complete
set of complex meromorphic first integrals in a neighborhood of the Lagrangian
solution.

</DOC>
<DOC>
<DOCNO> 69460 </DOCNO>
Double Inflation in Supergravity and the Boomerang Observations


  One of the biggest mystery of the recent observation of cosmic microwave
background anisotropies by the boomerang team is insignificance of the second
acoustic peak in the angular power spectrum. It is very difficult to explain
such a low amplitude without assuming the higher baryon density than predicted
by the Big Bang Nucleosynthesis (BBN). Employing the double inflation model in
supergravity, we show that the density fluctuations produced by this inflation
model can produce a sufficient low second acoustic peak with the standard value
of the baryon density from BBN. It is shown that these density fluctuations are
also consistent with the observations of cluster abundances and galaxy
distributions.

</DOC>
<DOC>
<DOCNO> 119248 </DOCNO>
Maximum Entropy Reconstruction of the Interstellar Medium: I. Theory


  We have developed a technique to map the three-dimensional structure of the
local interstellar medium using a maximum entropy reconstruction technique. A
set of column densities N to stars of known distance can in principle be used
to recover a three-dimensional density field n, since the two quantities are
related by simple geometry through the equation N = C n, where C is a matrix
characterizing the stellar spatial distribution. In practice, however, there is
an infinte number of solutions to this equation. We use a maximum entropy
reconstruction algorithm to find the density field containing the least
information which is consistent with the observations. The solution obtained
with this technique is, in some sense, the model containing the minimum
structure. We apply the algorithm to several simulated data sets to demonstrate
its feasibility and success at recovering ``real'' density contrasts.
  This technique can be applied to any set of column densities whose end points
are specified. In a subsequent paper we shall describe the application of this
method to a set of stellar color excesses to derive a map of the dust
distribution, and to soft X-ray absorption columns to hot stars to derive a map
of the total density of the interstellar medium.

</DOC>
<DOC>
<DOCNO> 178662 </DOCNO>
Applicability of the orientation average formula in heavy-ion fusion


  In heavy-ion fusion reactions involving a well deformed nucleus, one often
assumes that the orientation of the target nucleus does not change during the
reaction. We discuss the accuracy of this procedure by analyzing the excitation
function of the fusion cross section and the fusion barrier distribution in the
reactions of $^{154}$Sm target with various projectiles ranging from $^{12}$C
to $^{40}$Ar. It is shown that the approximation gradually looses its accuracy
with increasing charge product of the projectile and target nuclei because of
the effects of finite excitation energy of the target nucleus. The relevance of
such inaccuracy in analyzing the experimental data is also discussed.

</DOC>
<DOC>
<DOCNO> 9761 </DOCNO>
Finite-temperature ordering in two-dimensional magnets


  We study the two dimensional quantum Heisenberg antiferromagnet on the square
lattice with easy-axis exchange anisotropy. By the semiclassical method called
pure-quantum self-consistent harmonic approximation we analyse several
thermodynamic quantities and investigate the existence of a finite temperature
transition, possibly describing the low-temperature critical behaviour
experimentally observed in many layered real compounds.
  We find that an Ising-like transition characterizes the model even when the
anisotropy is of the order of $10^{-2}J$ ($J$ being the intra-layer exchange
integral), as in most experimental situations. On the other hand, typical
features of the isotropic Heisenberg model are observed for both values of
anisotropy considered, one in the {\it quasi}-isotropic limit and the other in
a more markedly easy-axis region.
  The good agreement found between our theoretical results and the experimental
data relative to the real compound Rb$_2$MnF$_4$ shows that the insertion of
the easy-axis exchange anisotropy, with quantum effects properly taken into
account, provides a quantitative description and explanation of the
experimental data, thus allowing to recognize in such anisotropy the main agent
for the observed onset of finite temperature long-range order.

</DOC>
<DOC>
<DOCNO> 71982 </DOCNO>
Brane Mediated Supersymmetry Breaking


  We propose a mechanism for mediating supersymmetry breaking in Type I string
constructions. The basic set-up consists of a system of three D-branes: two
parallel D-branes, a matter D-brane and a source D-brane, with supersymmetry
breaking communicated via a third D-brane, the mediating D-brane, which
intersects both of the parallel D-branes. We discuss an example in which the
first and second family matter fields correspond to open strings living on the
intersection of the matter D-brane and mediating D-brane, while the gauge
fields, Higgs doublets and third family matter fields correspond to open
strings living on the mediating D-brane. As in gaugino mediated models, the
gauginos and Higgs doublets receive direct soft masses from the source brane,
and flavour-changing neutral currents are naturally suppressed since the first
and second family squarks and sleptons receive suppressed soft masses. However,
unlike the gaugino mediated model, the third family squarks and sleptons
receive unsuppressed soft masses, resulting in a very distinctive spectrum with
heavier stops, sbottoms and staus.

</DOC>
<DOC>
<DOCNO> 117388 </DOCNO>
Photometric modal discrimination in Delta Scuti and Gamma Doradus stars


  The potential of photometric methods for the identification of l, the degree
of spherical surface harmonic of a pulsating star, is investigated with special
emphasis on Stromgren photometry applied to delta Scuti and gamma Dor
variables. Limitations of actual model atmospheres when fine precision is
required for the calculations of partial derivatives and integrals, which
depend on limb darkening coefficients, are discussed. Two methods are discussed
to calculate the phase lags, the angle between maximum temperature and minimum
radius, and R, a parameter which describes departure from adiabaticity of the
atmospheres of these pulsating stars. These quantities appear to be very
dependent on the convection as parametrized by the mixing length theory. When
one of the methods is applied to the gamma Dor stars gives phase lags close to
0 degrees, which are 90-180 degrees out of phase from typical delta Scuti
stars. Examples are given for some High Amplitude Delta Scuti Stars (HADS)
where the method can be easily applied and gives results consistent to
interpret them as radial (l=0) pulsating stars. Other low amplitude delta Scuti
stars could be oscillating in a non-radial (l=1, 2) mode. Multi-band photometry
is concluded to be a very powerful tool for mode identification of delta Scuti
and gamma Dor stars, specially with the more accurate photometry that will be
achieved in the near future with the asteroseismological space missions now in
progress.

</DOC>
<DOC>
<DOCNO> 70361 </DOCNO>
Generalized polarizabilities of the proton in a constituent quark model


  We study low-energy virtual Compton scattering off the proton within the
framework of a nonrelativistic constituent quark model.
   The Compton tensor is divided into two separately gauge-invariant
contributions.
   The first consists of the groundstate propagation in the direct and crossed
channels together with an appropriately chosen term to satisfy gauge
invariance.
   The residual part contains the relevant structure information characterized
by the so-called generalized polarizabilities.
   We discuss two different schemes to obtain the generalized polarizabilities
from the residual term.
   Explicit predictions for the generalized polarizabilities are presented for
the Isgur-Karl model.
   Our results are compared with previous predictions in that model as well as
other approaches.

</DOC>
<DOC>
<DOCNO> 150566 </DOCNO>
D-Branes as Unstable Lumps in Bosonic Open String Field Theory


  We construct Dp-branes in bosonic string theory as unstable lumps in a
truncated string field theory of open strings on a D25-brane. We find that the
lowest level truncation gives good quantitative agreement with the predicted
D-brane tension and low-lying spectrum of the D-brane for sufficiently large p
and study the effect of the next level corrections for p=24. We show that a
U(1) gauge field zero mode on the D-brane arises through a mechanism
reminiscent of the Randall-Sundrum mechanism for gravity.

</DOC>
<DOC>
<DOCNO> 121514 </DOCNO>
Constraining our Universe with X-ray & Optical Cluster Data


  We have used recent X-ray and optical data in order to impose some
constraints on the cosmology and cluster scaling relations. Generically two
kind of hypotheses define our model. First we consider that the cluster
population is well described by the standard Press-Schechter (PS) formalism,
and second, these clusters are supposed to follow scaling relations with mass:
Temperature-Mass (T-M) and X-ray Luminosity-Mass (L_x - M). As a difference
with many other authors we do not assume specific scaling relations to model
cluster properties such as the usual $T-M$ virial relation or one observational
determination of the $L_x-T$ relation. Instead we consider general free
parameter scaling relations. With the previous model (PS plus scalings) we fit
our free parameters to several X-ray and optical data with the advantage over
many other works that we consider all the data sets at the same time. This
prevents us from being inconsistent with some of the available observations.
Among other interesting conclusions, we find that only low-density universes
are compatible with all the data considered and that the degeneracy between
$\Omega_m$ and $\sigma_8$ is broken. Also we obtain interesting limits on the
parameters characterizing the scaling relations.

</DOC>
<DOC>
<DOCNO> 13900 </DOCNO>
What do emulsification failure and Bose-Einstein condensation have in


  Ideal bosons and classical ring polymers formed via self-assembly, are known
to have the same partition function, and so analogous phase transitions. In
ring polymers, the analogue of Bose-Einstein condensation occurs when a ring
polymer of macroscopic size appears. We show that a transition of the same
general form occurs within a whole class of systems with self-assembly, and
illustrate it with the emulsification failure of a microemulsion phase of
water, oil and surfactant. As with Bose-Einstein condensation, the transition
occurs even in the absence of interactions.

</DOC>
<DOC>
<DOCNO> 9561 </DOCNO>
High Frequency Acousto-electric Single Photon Source


  We propose a single optical photon source for quantum cryptography based on
the acousto-electric effect. Surface acoustic waves (SAWs) propagating through
a quasi-one-dimensional channel have been shown to produce packets of electrons
which reside in the SAW minima and travel at the velocity of sound. In our
scheme these electron packets are injected into a p-type region, resulting in
photon emission. Since the number of electrons in each packet can be controlled
down to a single electron, a stream of single (or N) photon states, with a
creation time strongly correlated with the driving acoustic field, should be
generated.

</DOC>
<DOC>
<DOCNO> 10497 </DOCNO>
Non trivial overlap distributions at zero temperature


  We explore the consequences of Replica Symmetry Breaking at zero temperature.
We introduce a repulsive coupling between a system and its unperturbed ground
state. In the Replica Symmetry Breaking scenario a finite coupling induces a
non trivial overlap probability distribution among the unperturbed ground state
and the one in presence of the coupling. We find a closed formula for this
probability for arbitrary ultrametric trees, in terms of the parameters
defining the tree. The same probability is computed in numerical simulations of
a simple model with many ground states, but no ultrametricity: polymers in
random media in 1+1 dimension. This gives us an idea of what violation of our
formula can be expected in cases when ultrametricity does not hold.

</DOC>
<DOC>
<DOCNO> 117396 </DOCNO>
The Stellar Population Histories of Local Early-Type Galaxies. I.


  We present single stellar population (SSP) equivalent ages, metallicities,
and abundance ratios for local elliptical galaxies derived from Hbeta, Mgb, and
<Fe> absorption line strengths. We use an extension of the Worthey (1994)
stellar population models that incorporates non-solar line-strength "response
functions" by Tripicco & Bell (1995), allowing us to correct the models for the
enhancements of Mg and other alpha-like elements relative to the Fe-peak
elements. SSP-equivalent ages of local ellipticals from Gonzalez (1993) are
found to vary widely, 1.5 < t < 18 Gyr, while metallicities [Z/H] and
enhancement ratios [E/Fe] are strongly peaked around <[Z/H]>=+0.26 and
<[E/Fe]>=+0.20 (in an aperture of radius Re/8). The enhancement ratios are
milder than previous estimates, owing to the application of non-solar abundance
corrections to both Mgb and <Fe> for the first time. Gradients in stellar
populations within galaxies are found to be mild, with SSP-equivalent age
decreasing by 25%, metallicity decreasing by <[Z/H]>=0.20 dex, and [E/Fe]
remaining nearly constant out to an aperture of radius Re/2 for nearly all
systems. Our ages have an overall zeropoint uncertainty of at least 25% due to
uncertainties in the stellar evolution prescription, the oxygen abundance, the
effect of non-solar abundances on the isochrones, and other unknowns. However,
the relative age rankings of stellar populations should be largely unaffected
by these errors. In particular, the large spread in ages appears to be real and
cannot be explained by contamination of Hbeta by blue stragglers or hot
horizontal branch stars, or by fill-in of Hbeta by emission. Correlations
between these derived SSP-equivalent parameters and other galaxy observables
will be discussed in future papers. (Abridged)

</DOC>
<DOC>
<DOCNO> 102040 </DOCNO>
Matrix Powers of Column-Justified Pascal Triangles and Fibonacci


  If L, respectively R are matrices with entries binom{i-1,j-1}, respectively
binom{i-1,n-j}, it is known that L^2 = I (mod 2), respectively R^3 = I (mod 2),
where I is the identity matrix of dimension n > 1 (see P10735-May 1999 issue of
the American Mathematical Monthly). We generalize it for any prime p, and give
a beautiful connection to Fibonacci numbers.

</DOC>
<DOC>
<DOCNO> 13736 </DOCNO>
Negative heat capacities and first order phase transitions in nuclei and


  The origin of predicted and observed anomalies in caloric curves of nuclei
and other mesoscopic systems is investigated. It is shown that a
straightforward thermodynamical treatment of an evaporating liquid drop leads
to a backbending in the caloric curve and to negative specific heats in the two
phase coexistence region. The cause is found not in the generation of
additional surface, but in the progressive reduction of the drop's radius, and
surface, with evaporation.

</DOC>
<DOC>
<DOCNO> 117176 </DOCNO>
Magnetic Helicity Conservation and Astrophysical Dynamos


  We construct a magnetic helicity conserving dynamo theory which incorporates
a calculated magnetic helicity current. In this model the fluid helicity plays
a small role in large scale magnetic field generation. Instead, the dynamo
process is dominated by a new quantity, derived from asymmetries in the second
derivative of the velocity correlation function, closely related to the `twist
and fold' dynamo model. The turbulent damping term is, as expected, almost
unchanged. Numerical simulations with a spatially constant fluid helicity and
vanishing resistivity are not expected to generate large scale fields in
equipartition with the turbulent energy density. The prospects for driving a
fast dynamo under these circumstances are uncertain, but if it is possible,
then the field must be largely force-free. On the other hand, there is an
efficient analog to the $\alpha-\Omega$ dynamo. Systems whose turbulence is
driven by some anisotropic local instability in a shearing flow, like real
stars and accretion disks, and some computer simulations, may successfully
drive the generation of strong large scale magnetic fields, provided that
$\partial_r\Omega< \partial_\theta v_z\omega_\theta>>0$. We show that this
criterion is usually satisfied. Such dynamos will include a persistent,
spatially coherent vertical magnetic helicity current with the same sign as
$-\partial_r\Omega$, that is, positive for an accretion disk and negative for
the Sun. We comment on the role of random magnetic helicity currents in storing
turbulent energy in a disordered magnetic field, which will generate an
equipartition, disordered field in a turbulent medium, and also a declining
long wavelength tail to the power spectrum. As a result, calculations of the
galactic `seed' field are largely irrelevant.

</DOC>
<DOC>
<DOCNO> 68557 </DOCNO>
Scalar Mesons and Glueballs in a Chiral U(3)xU(3) Quark Model with 't


  In a U(3)x U(3) quark chiral model of the Nambu-Jona-Lasinio type with the 't
Hooft interaction, the ground scalar isoscalar mesons and a scalar glueball are
described. The glueball (dilaton) is introduced into the effective meson
Lagrangian written in a chirally symmetric form on the base of scale
invariance. The singlet-octet mixing of scalar isoscalar mesons and their
mixing with the glueball are taken into account. Mass spectra of the scalar
mesons and glueball and their strong decays are described.

</DOC>
<DOC>
<DOCNO> 10137 </DOCNO>
Critical Transverse Forces in Weakly Pinned Driven Vortex Systems


  We present simulation results of the moving Bragg glass regime of a driven
two-dimensional vortex system in the presence of a smoothly varying weak
pinning potential. We study the critical transverse force and (i) demonstrate
that it can be an order of magnitude larger than previous estimates (ii) show
that it is still observable when the system is driven along low higher-order
lattice vectors. We confirm theoretical predictions that the critical
transverse force is the order parameter of the so-called moving glass phase,
and provide data to support experimentalists verifying the existence of a
critical transverse force.

</DOC>
<DOC>
<DOCNO> 70797 </DOCNO>
The description for the spin polarizabilities of hadrons based on the


  On the basis of the correspondence principle between the relativistic moving
medium electrodynamics and relativistic quantum field theory the covariant
Lagrangian of the electromagnetic field interaction with the polarized spin
particles have been obtained. This Lagrangian satisfies the main relativistic
quantum field theory requirements and contains four independent covariant spin
structures, which have particular physical meaning. It is shown that the spin
polarizabilities give the contribution to the amplitude for Compton scattering
on the spin-1/2 hadron in the ${\cal O}(\omega^3)$.

</DOC>
<DOC>
<DOCNO> 70085 </DOCNO>
Neutralino Phenomenology at LEP2 in Supersymmetry with Bilinear Breaking


  We discuss the phenomenology of the lightest neutralino in models where an
effective bilinear term in the superpotential parametrizes the explicit
breaking of R-parity. We consider supergravity scenarios where the lightest
supersymmetric particle (LSP) is the lightest neutralino and which can be
explored at LEP2. We present a detailed study of the LSP decay properties and
general features of the corresponding signals expected at LEP2. We also
contrast our model with gauge mediated supersymmetry breaking.

</DOC>
<DOC>
<DOCNO> 68623 </DOCNO>
Supersymmetric left-right model and scalar potential


  We construct a scalar potential of supersymmetric left-right model in the
limit when supersymmetry is valid.

</DOC>
<DOC>
<DOCNO> 67997 </DOCNO>
Muon Collider Physics at Very High Energies


  Muon colliders might greatly extend the energy frontier of collider physics.
One can contemplate circular colliders with center-of-mass energies in excess
of 10 TeV. Some physics issues that might be relevant at such a machine are
discussed.

</DOC>
<DOC>
<DOCNO> 170599 </DOCNO>
Comment on `Decomposition of pure states of a quantum register'


  I. Raptis and R. Zapatrin in the quant-ph/0010104 show possibility to express
general state of $l$-qubits quantum register as sum at most $2^l-l$ product
states. In the comment is suggested more simple construction with possibility
of generalization for decomposition of tensor product of Hilbert spaces with
arbitrary dimension $n$ (here simplicial complexes used in the article
mentioned above would not be applied directly). In this case it is
decomposition with $n^l-(n^2-n)l/2$ product states.

</DOC>
<DOC>
<DOCNO> 117480 </DOCNO>
Probing the width of the MACHO mass function


  The simplest interpretation of the microlensing events observed towards the
Large Magellanic Cloud is that approximately half of the mass of the Milky Way
halo is in the form of MAssive Compact Halo Objects with $M \sim 0.5
M_{\odot}$. This poses severe problems for stellar MACHO candidates, and leads
to the consideration of more exotic objects such as primordial black holes
(PBHs). Constraining the MACHO mass function will shed light on their nature.
Using the current data we find, for four halo models, the best fit
delta-function, power law and PBH mass functions. The best fit PBH mass
functions, despite having significant finite width, have likelihoods which are
similar to, and for one particular halo model greater than, those of the best
fit delta functions. We also find that if the correct halo model is known then
$\sim$ 500 events will be sufficient to determine whether the MACHO mass
function has significant width, and will also allow determination of the mass
function parameters to $\sim 5%$.

</DOC>
<DOC>
<DOCNO> 119586 </DOCNO>
beta-model and cooling flows in X-ray clusters of galaxies


  The spatial emission from the core of cooling flow clusters of galaxies is
inadequately described by a beta-model(Cavaliere and Fusco-Femiano 1976).
Spectrally, the central region of these clusters are well approximated with a
two-temperature model, where the inner temperature represents the multiphase
status of the core and the outer temperature is a measure of the ambient gas
temperature.Following this observational evidence, I extend the use of the
beta-model to a two-phase gas emission, where the two components coexist within
a boundary radius r_cool and the ambient gas alone fills the volume shell at
radius above r_cool. This simple model still provides an analytic expression
for the total surface brightness profile. Based upon a physically meaningful
model for the X-ray emission, this formula can be used (i) to improve
significantly the modeling of the surface brightness profile of cooling flow
clusters of galaxies when compared to the standard beta-model results, (ii) to
constrain properly the physical characteristics of the intracluster plasma in
the outskirts, like, e.g., the ambient gas temperature.

</DOC>
<DOC>
<DOCNO> 12119 </DOCNO>
Short pitch structures in smectics with interactions over more than two


  Phenomenological model of chiral polar smectics is introduced with
interactions up to the fourth neighboring layers. The minimization of the free
energy gives three stable structures: the ferroelectric Sm C$^*$ phase, the
antiferroelectric Sm C$^*_A$ phase and the hellicoidally modulated structure of
the Sm C$^*_H$ phase. The phase Sm C$^*_\alpha$ can be recognized as the Sm
C$^*_H$ phase below Sm A phase and as the Sm C$^*_{FI2}$ phase or as the Sm
C$^*_{FI1}$ phase when appearing between the Sm C$^*$ phase and the Sm C$^*_A$
phase. Stability of these phases is analyzed and the phase diagram in the space
of model parameters is presented.

</DOC>
<DOC>
<DOCNO> 10255 </DOCNO>
Spin tunneling of trigonal and hexagonal ferromagnets in an arbitrarily


  The quantum tunneling of the magnetization vector are studied theoretically
in single-domain ferromagnetic nanoparticles placed in an external magnetic
field at an arbitrarily directed angle in the $ZX$ plane. We consider the
magnetocrystalline anisotropy with trigonal and hexagonal crystal symmetry,
respectively. By applying the instanton technique in the spin-coherent-state
path-integral representation, we calculate the tunnel splittings, the tunneling
rates and the crossover temperatures in the low barrier limit for different
angle ranges of the external magnetic field ($\theta_{H}=\pi/2$,
$\pi/2\ll\theta_{H}\ll\pi$, and $\theta_{H}=\pi$). Our results show that the
tunnel splittings, the tunneling rates and the crossover temperatures depend on
the orientation of the external magnetic field distinctly, which provides a
possible experimental test for magnetic quantum tunneling in nanometer-scale
single-domain ferromagnets.

</DOC>
<DOC>
<DOCNO> 170058 </DOCNO>
On Arbitrary Phases in Quantum Amplitude Amplification


  We consider the use of arbitrary phases in quantum amplitude amplification
which is a generalization of quantum searching. We prove that the phase
condition in amplitude amplification is given by
$\tan(\varphi/2)=\tan(\phi/2)(1-2a)$, where $\phi$ and $\varphi$ are the phases used
and where $a$ is the success probability of the given algorithm. Thus the
choice of phases depends nontrivially and nonlinearly on the success
probability. Utilizing this condition, we give methods for constructing quantum
algorithms that succeed with certainty and for implementing arbitrary
rotations. We also conclude that phase errors of order up to
$\frac{1}{\sqrt{a}}$ can be tolerated in amplitude amplification.

</DOC>
<DOC>
<DOCNO> 100049 </DOCNO>
Asymptotics of Multivariate Sequences, part I. Smooth points of the


  Given a multivariate generating function F, we determine asymptotics for the
coefficients. Our approach is to use Cauchy's integral formula near singular
points of F, resulting in a tractable oscillating integral. This paper treats
the case where the singular point of F is a smooth point of a surface of poles.
Companion papers will treat singular points of F where the local geometry is
more complicated, and for which other methods of analysis are not known.

</DOC>
<DOC>
<DOCNO> 150970 </DOCNO>
Dynamical Mass and Parity Condensate in Varying Topological Mass


  We investigate how a dynamical mass of a fermion is affected by a topological
mass of a gauge field in a Maxwell-Chern-Simons $QED_3$ coupled with a
two-component fermion. The dynamical mass and also a parity condensate are
estimated by using a non-perturbative Schwinger-Dyson method. In particular, we
study a limit of vanishing the topological mass in detail and clarify a linking
between theories with and without a Chern-Simons term in a non-perturbative
level.

</DOC>
<DOC>
<DOCNO> 102897 </DOCNO>
Minimum multiplicities of subgraphs and Hamiltonian systems


  Let G be a finite simple graph with automorphism group A(G). Then a spanning
subgraph U of G is a fixing subgraph of G if G contains exactly $| A(G)|/ |
A(G) \cap A(U)| $ subgraphs isomorphic to U: the graph G must always contain at
least this number. If in addition $A(U) \subseteq A(G)$ then U is a strong
fixing subgraph. Fixing subgraphs are important in many areas of graph theory.
We consider them in the context of Hamiltonian graphs

</DOC>
<DOC>
<DOCNO> 9839 </DOCNO>
LiVGe2O6, an anomalous quasi 1D, $S = 1$ system, as revealed by NMR


  We report the results of $^{7}$Li nuclear magnetic resonance (NMR) studies of
LiVGe$_{2}$O$_{6}$, a quasi one--dimensional spin $S = 1$ model system, at low
temperatures. Our data, including NMR spectra and the temperature dependence of
the spin-lattice relaxation rate $T_{1}^{-1}$, indicate a first order phase
transition to occur at $T_{c}\simeq 23$ K. The NMR response of
LiVGe$_{2}$O$_{6}$ below $T_{c}$ suggests that the ordered phase is
antiferromagnetic and has unusual features. Possible reasons for this
unexpected behavior are discussed.

</DOC>
<DOC>
<DOCNO> 169703 </DOCNO>
On the Complexity of Quantum ACC


  For any $q > 1$, let $\MOD_q$ be a quantum gate that determines if the number
of 1's in the input is divisible by $q$. We show that for any $q,t > 1$,
$\MOD_q$ is equivalent to $\MOD_t$ (up to constant depth). Based on the case
$q=2$, Moore \cite{moore99} has shown that quantum analogs of AC$^{(0)}$,
ACC$[q]$, and ACC, denoted QAC$^{(0)}_{wf}$, QACC$[2]$, QACC respectively,
define the same class of operators, leaving $q > 2$ as an open question. Our
result resolves this question, proving that QAC$^{(0)}_{wf} =$ QACC$[q] = $
QACC for all $q$. We also develop techniques for proving upper bounds for QACC
in terms of related language classes. We define classes of languages EQACC,
NQACC and BQACC$_{\rats}$. We define a notion $\log$-planar QACC operators and
show the appropriately restricted versions of EQACC and NQACC are contained in
P/poly. We also define a notion of $\log$-gate restricted QACC operators and
show the appropriately restricted versions of EQACC and NQACC are contained in
TC$^{(0)}$. To do this last proof, we show that TC$^{(0)}$ can perform iterated
addition and multiplication in certain field extensions. We also introduce the
notion of a polynomial-size tensor graph and show that families of such graphs
can encode the amplitudes resulting from apply an arbitrary QACC operator to an
initial state.

</DOC>
<DOC>
<DOCNO> 84321 </DOCNO>
Gravitating Instantons In 3 Dimensions


  We study the Einstein-Chern-Simons gravity coupled to Yang-Mills-Higgs theory
in three dimensional Euclidean space with cosmological constant. The classical
equations reduce to Bogomol'nyi type first order equations in curved space.
There are BPS type gauge theory instanton (monopole) solutions of finite action
in a gravitational instanton which itself has a finite action. We also discuss
gauge theory instantons in the vacuum (zero action) AdS space. In addition we
point out to some exact solutions which are singular.

</DOC>
<DOC>
<DOCNO> 71381 </DOCNO>
Variable flavor number schemes versus fixed order perturbation theory


  Data for D*(2010) meson electroproduction in the range 10 < Q2 < 1350 GeV^2
has recently been presented by the ZEUS collaboration at HERA. We use these
results together with previously published data for Q2 > 1 GeV^2 to test
whether one can distinguish between different theoretical schemes for charm
quark electroproduction. We find that up to the largest Q2 measured, it is not
possible to make such a differentiation. Then we point out the regions where
differences between the various schemes arise.

</DOC>
<DOC>
<DOCNO> 117326 </DOCNO>
Parametric Processes in a Strong-Coupling Planar Microcavity


  I present a theoretical treatment of parametric scattering in strong coupling
semiconductor microcavities to model experiments in which parametric oscillator
behaviour has been observed. The model consists of a non-linear excitonic
oscillator coupled to a cavity mode which is driven by the external fields, and
predicts the output power, below threshold gain and spectral blue shifts of the
parametric oscillator. The predictions are found to be in excellent agreement
with the experimental data.

</DOC>
<DOC>
<DOCNO> 99776 </DOCNO>
A new weight system on chord diagrams via hyperk\"ahler geometry


  A weight system on graph homology was constructed by Rozansky and Witten
using a compact hyperk\"ahler manifold. A variation of this construction
utilizing holomorphic vector bundles over the manifold gives a weight system on
chord diagrams. We investigate these weights from the hyperk\"ahler geometry
point of view.

</DOC>
<DOC>
<DOCNO> 8116 </DOCNO>
Analytic Lyapunov exponents in a classical nonlinear field equation


  It is shown that the nonlinear wave equation $\partial_t^2\phi - \partial^2_x
\phi -\mu_0\partial_x(\partial_x\phi)^3 =0$, which is the continuum limit of
the Fermi-Pasta-Ulam (FPU) beta model, has a positive Lyapunov exponent
lambda_1, whose analytic energy dependence is given. The result (a first
example for field equations) is achieved by evaluating the lattice-spacing
dependence of lambda_1 for the FPU model within the framework of a Riemannian
description of Hamiltonian chaos. We also discuss a difficulty of the
statistical mechanical treatment of this classical field system, which is
absent in the dynamical description.

</DOC>
<DOC>
<DOCNO> 151065 </DOCNO>
Novel Phase Structure of Twisted O(N) phi^4 model on M^D-1 \times S^1


  We study the O(N) $\phi^4$ model compactified on $M^{D-1}\otimes S^1$, which
allows to impose twisted boundary conditions for the $S^1$-direction. The O(N)
symmetry can be broken to $H$ explicitly by the boundary conditions and further
broken to $I$ spontaneously by vacuum expectation values of the fields. The
symmetries $H$ and $I$ are completely classified and the model turns out to
have unexpectedly a rich phase structure. The unbroken symmetry $I$ is shown to
depend on not only the boundary conditions but also the radius of $S^1$, and
the symmetry breaking patterns are found to be unconventional. The spontaneous
breakdown of the translational invariance is also discussed.

</DOC>
<DOC>
<DOCNO> 70826 </DOCNO>
Reconstructing the inflationary power spectrum from CMBR data


  The Cosmic Microwave Background Radiation (CMBR) holds information about
almost all the fundamental cosmological parameters, and by performing a
likelihood analysis of high precision CMBR fluctuation data, these parameters
can be inferred. However, this analysis relies on assumptions about the initial
power spectrum, which is usually taken to be a featureless power-law, P(k) ~
k^{n_s-1}. Many inflationary models predict power spectra with non-power law
features. We discuss the possibility for detecting such features by describing
the power spectrum as bins in k-space. This method for power spectrum
reconstruction is demonstrated in practise by performing likelihood
optimization on synthetic spectra, and the difficulties arising from
reconstructing smooth features using discontinuous bins are discussed in
detail.

</DOC>
<DOC>
<DOCNO> 67863 </DOCNO>
Electrons, New Physics, and the Future of Parity-Violation


  The study of parity-violation in semi-leptonic processes has yielded
important insights into the structure of the Standard Model and the
substructure of the nucleon. I discuss the future of semi-leptonic
parity-violation and the role it might play in uncovering physics beyond the
Standard Model.

</DOC>
<DOC>
<DOCNO> 100175 </DOCNO>
Formal dimension for semisimple symmetric spaces


  In this paper we generalize Harish Chandra's formula for the formal dimension
of a representation of the holomorphic discrete series of a hermitian Lie group
$G$ to semisimple symmetric spaces $G/H$.

</DOC>
<DOC>
<DOCNO> 102529 </DOCNO>
Geometric monodromy and the hyperbolic disc


  Symplectic four-manifolds give rise to Lefschetz fibrations, which are
determined by monodromy representations of free groups in mapping class groups.
We study the topology of Lefschetz fibrations by analysing the action of the
monodromy on the universal cover of a smooth fibre. We give new and simple
proofs that Lefschetz fibrations arising from pencils (i.e. with exceptional
sections) never split as non-trivial fibre sums, and that no simple closed
curve can be invariant to isotopy under the monodromy representation.

</DOC>
<DOC>
<DOCNO> 100132 </DOCNO>
Noncommutative Algebraic Equations and Noncommutative Eigenvalue Problem


  We analyze the perturbation series for noncommutative eigenvalue problem
$AX=X\lambda$ where $\lambda$ is an element of a noncommutative ring, $ A$ is a
matrix and $X$ is a column vector with entries from this ring. As a corollary
we obtain a theorem about the structure of perturbation series for Tr $x^r$
where $x$ is a solution of noncommutative algebraic equation (for $r=1$ this
theorem was proved by Aschieri, Brace, Morariu, and Zumino, hep-th/0003228, and
used to study Born-Infeld lagrangian for the gauge group $U(1)^k$).

</DOC>
<DOC>
<DOCNO> 10041 </DOCNO>
Lineshape predictions via Bethe ansatz for the one-dimensional spin-1/2


  The spin fluctuations parallel to the external magnetic field in the ground
state of the one-dimensional (1D) s=1/2 Heisenberg antiferromagnet are
dominated by a two-parameter set of collective excitations. In a cyclic chain
of N sites and magnetization 0<M_z<N/2, the ground state, which contains 2M_z
spinons, is reconfigured as the physical vacuum for a different species of
quasi-particles, identifiable in the framework of the coordinate Bethe ansatz
by characteristic configurations of Bethe quantum numbers. The dynamically
dominant excitations are found to be scattering states of two such
quasi-particles. For N -> \infty, these collective excitations form a continuum
in (q,\omega)-space with an incommensurate soft mode. Their matrix elements in
the dynamic spin structure factor S_{zz}(q,\omega) are calculated directly from
the Bethe wave functions for finite N. The resulting lineshape predictions for
N -> \infty complement the exact results previously derived via algebraic
analysis for the exact 2-spinon part of S_{zz}(q,\omega) in the zero-field
limit. They are directly relevant for the interpretation of neutron scattering
data measured in nonzero field on quasi-1D antiferromagnetic compounds.

</DOC>
<DOC>
<DOCNO> 40209 </DOCNO>
Present and Future Oscillation Experiments at Reactors


  This is a report on recent progress and developments since the NANP'99
Conference in current and future long baseline (~1 km) and very long baseline
(~100 - 800 km) oscillation experiments at reactors. These experiments, under
certain assumptions, can fully reconstruct the internal mass structure of the
electron neutrino and provide laboratory test of solar and atmospheric neutrino
problems.

</DOC>
<DOC>
<DOCNO> 11168 </DOCNO>
Geometric Phases and Multiple Degeneracies in Harmonic Resonators


  In a recent experiment Lauber et al. have deformed cyclically a microwave
resonator and have measured the adiabatic normal-mode wavefunctions for each
shape along the path of deformation. The nontrivial observed cyclic phases
around a 3-fold degeneracy were accounted for by Manolopoulos and Child within
an approximate theory. However, open-path geometrical phases disagree with
experiment. By solving exactly the problem, we find unsuspected extra
degeneracies around the multiple one that account for the measured phase
changes throughout the path. It turns out that proliferation of additional
degeneracies around a multiple one is a common feature of quantum mechanics.

</DOC>
<DOC>
<DOCNO> 122694 </DOCNO>
The EUV excess emission of the Virgo and A1795 clusters - re-observation


  The Virgo and A1795 clusters of galaxies were re-observed by EUVE with {\it
in situ} background measurements by pointing at small offsets. Earlier, a
similar re-observational strategy applied to the cluster A2199 revealed that
the background radial profile was consistent with a flat distribution, and
therefore the original method of extracting cluster EUV signals by the
subtraction of an aymptotically determined background was valid. It is shown
here that the same conclusions hold for the current sample. A model of the
background was obtained from its known properties and the {\it in situ}
measurements, and the subtracted cluster fluxes remain in agreement with those
reported in our discovery papers. They are also consistent with results from
the most conservative procedure of direct point-to-point subtraction of the
{\it in situ} background and proper error propagation, which still preserves
the existence of the EUV excess and its rising radial trend. We present
evidence which argues against the soft excess as due to peculiarities in the
line-of-sight Galactic absorption. The data appear to favor a thermal origin of
the emission.

</DOC>
<DOC>
<DOCNO> 67714 </DOCNO>
Pade Interpolation: Methodology and Application to Quarkonium


  A novel application of the Pade approximation is proposed in which the Pade
approximant is used as an interpolation for the small and large coupling
behaviors of a physical system, resulting in a prediction of the behavior of
the system at intermediate couplings. This method is applied to quarkonium
systems and reasonable values for the c and b quark masses are obtained.

</DOC>
<DOC>
<DOCNO> 8589 </DOCNO>
Theoretical Perspectives on Spintronics and Spin-Polarized Transport


  Selected problems of fundamental importance for spintronics and
spin-polarized transport are reviewed, some of them with a special emphasis on
their applications in quantum computing and coherent control of quantum
dynamics. The role of the solid-state environment in the decoherence of
electron spins is discussed. In particular, the limiting effect of the
spin-orbit interaction on spin relaxation of conduction electrons is carefully
examined in the light of recent theoretical and experimental progress. Most of
the proposed spintronic devices involve spin-polarized transport across
interfaces in various hybrid structures. The specific example discussed here,
of a magnetic semiconductor/superconductor interface, displays many intricacies
which a complex spin-dependent interface introduces in the spin-polarized
transport. It is proposed that pairs of entangled electrons in a superconductor
(Cooper pairs) can be transfered to a non-superconducting region, and
consequently separated for a transport study of the spin entanglement. Several
important theoretical proposals for quantum computing are based on electronic
and nuclear spin entanglement in a solid. Physical requirements for these
proposals to be useful are discussed and some alternative views are presented.
Finally, a recent discovery of optical control of nuclear spins in
semiconductors is reviewed and placed in the context of a long-standing search
for electronic control of nuclear dynamics.

</DOC>
<DOC>
<DOCNO> 12268 </DOCNO>
Formation of Liesegang patterns: Simulations using a kinetic Ising model


  A kinetic Ising model description of Liesegang phenomena is studied using
Monte Carlo simulations. The model takes into account thermal fluctuations,
contains noise in the chemical reactions, and its control parameters are
experimentally accessible. We find that noisy, irregular precipitation takes
place in dimension d=2 while, depending on the values of the control
parameters, either irregular patterns or precipitation bands satisfying the
regular spacing law emerge in d=3.

</DOC>
<DOC>
<DOCNO> 116867 </DOCNO>
CCT, a Code to Automate the Design of Coupled Cavities


  The CCT (Coupled Cavity Tuning) code automates the RF calculations and sizing
of RF cavities for the CCL (Coupled Cavity Linac) structures of APT. It is
planned to extend the code to the CCDTL (Coupled Cavity Drift Tube Linac). The
CCT code controls the CCLFISH code, a member of the Poisson Superfish series of
codes [1]. CCLFISH performs RF calculations and tunes the geometry of
individual cavities, including an accelerating cavity (AC) and a coupling
cavity (CC). CCT also relates the AC and CC by means of equations that describe
the coupling slot between cavities. These equations account for the direct
coupling, the next nearest neighbor coupling between adjacent AC's, and the
frequency shifts in the AC and CC caused by the slot. Given design objectives
of a coupling coefficient k, the pi/2 mode frequency, and the net frequency of
the CC, the CCT code iterates to solve for the geometry of the AC and CC and
the separation distance between them (this controls the slot size), satisfying
the design objectives. The resulting geometry is used to automate CAD drawing
preparation. The code can also be used in "as-designed" mode to calculate the
frequencies and coupling of a specified configuration. An overview of the code
is presented.

</DOC>
<DOC>
<DOCNO> 117929 </DOCNO>
Nonlinear Velocity-Density Coupling: Analysis by Second-Order


  Cosmological linear perturbation theory predicts that the peculiar velocity
$V(x)$ and the matter overdensity $\delta(x)$ at a same point $x$ are
statistically independent quantities, as log as the initial density
fluctuations are random Gaussian distributed. However nonlinear gravitational
effects might change the situation. Using framework of second-order
perturbation theory and the Edgeworth expansion method, we study local density
dependence of bulk velocity dispersion that is coarse-grained at a weakly
nonlinear scale. For a typical CDM model, the first nonlinear correction of
this constrained bulk velocity dispersion amounts to $\sim 0.3\delta$ (Gaussian
smoothing) at a weakly nonlinear scale with a very weak dependence on
cosmological parameters. We also compare our analytical prediction with
published numerical results given at nonlinear regimes.

</DOC>
<DOC>
<DOCNO> 101562 </DOCNO>
Introducing Quaternionic Gerbes


  The notion of a quaternionic gerbe is presented as a new way of bundling
algebraic structures over a four manifold. The structure groupoid of this
fibration is described in some detail. The Euclidean conformal group R*SO(4)
appears naturally as a (non-commutative) monoidal structure on this groupoid.
Using this monoidal structure we indicate the existence of a canonical
quaternionic gerbe associated to a conformal structure on a four manifold.

</DOC>
<DOC>
<DOCNO> 84329 </DOCNO>
Bulk Fields in Dilatonic and Self-Tuning Flat Domain Walls


  We study the Kaluza-Klein zero modes of massless bulk fields with various
spins in the background of dilatonic and self-tuning flat domain walls. We find
that the zero modes of all the massless bulk fields in such domain wall
backgrounds are normalizable, unlike those in the background of the
non-dilatonic domain wall with infinite extra space of Randall and Sundrum. In
particular, gravity in the bulk of dilatonic domain walls is effectively
compactified to the Einstein gravity with vanishing cosmological constant and
nonzero gravitational constant in one lower dimensions for any values of
dilaton coupling parameter, provided the warp factor is chosen to decrease on
both sides of the domain wall, in which case the tension of the domain wall is
positive. However, unexpectedly, for the self-tuning flat domain walls, the
cosmological constant of the zero mode effective gravity action in one lower
dimensions does not vanish, indicating the need for additional ingredient or
modification necessary in cancellation of the unexpected cosmological constant
in the graviton zero mode effective action.

</DOC>
<DOC>
<DOCNO> 102726 </DOCNO>
Random Sparse Polynomial Systems


  Let f:=(f^1,\...,f^n) be a sparse random polynomial system. This means that
each f^i has fixed support (list of possibly non-zero coefficients) and each
coefficient has a Gaussian probability distribution of arbitrary variance.
  We express the expected number of roots of f inside a region U as the
integral over U of a certain mixed volume form. When U = (C^*)^n, the classical
mixed volume is recovered.
  The main result in this paper is a bound on the probability that the
condition number of f on the region U is larger than 1/epsilon. This bound
depends on the integral of the mixed volume form over U, and on a certain
intrinsic invariant of U as a subset of a toric manifold.
  Polynomials with real coefficients are also considered, and bounds for the
expected number of real roots and for the condition number are given.
  The connection between zeros of sparse random polynomial systems, Kahler
geometry, and mechanics (momentum maps) is discussed.

</DOC>
<DOC>
<DOCNO> 122735 </DOCNO>
Histogram Analysis of Gallex, GNO and Sage Neutrino Data: Further


  If the solar neutrino flux were constant, as is widely assumed, the histogram
of flux measurements would be unimodal. On the other hand, sinusoidal or
square-wave modulation (either periodic or stochastic) may lead to a bimodal
histogram. We here present evidence that the neutrino flux histogram is in fact
bimodal. We analyze all available data from gallium experiments, coordinating
results from the GALLEX and GNO experiments into one data set, and adopting
results from the SAGE experiment as another data set. The two histograms, from
the two data sets, are consistent in showing peaks in the range 45-75 SNU and
90-120 SNU, with a valley in between. By combining the data into one data set,
we may form more detailed histograms; these strengthen the case that the flux
is bimodal. A preliminary statistical analysis indicates that the bimodal
character of the solar neutrino flux is highly significant. Since the upper
peak is close to the expected flux (120-140 SNU), we may infer that the
neutrino deficit is due to time-varying attenuation of the flux produced in the
core. We estimate the time scale of this variation to be in the range 10-60
days. Attenuation that varies on such a time scale is suggestive of the
influence of solar rotation, and points towards a process involving the solar
magnetic field in conjunction with a nonzero neutrino magnetic moment.

</DOC>
<DOC>
<DOCNO> 116451 </DOCNO>
Tsallis' entropy maximization procedure revisited


  The proper way of averaging is an important question with regards to Tsallis'
Thermostatistics. Three different procedures have been thus far employed in the
pertinent literature. The third one, i.e., the Tsallis-Mendes-Plastino (TMP)
normalization procedure, exhibits clear advantages with respect to earlier
ones. In this work, we advance a distinct (from the TMP-one) way of handling
the Lagrange multipliers involved in the extremization process that leads to
Tsallis' statistical operator. It is seen that the new approach considerably
simplifies the pertinent analysis without losing the beautiful properties of
the Tsallis-Mendes-Plastino formalism.

</DOC>
<DOC>
<DOCNO> 123039 </DOCNO>
Metallicity Gradients in X-ray Clusters of Galaxies


  We present the projected metallicity profiles for a sample of 17 rich galaxy
clusters observed by BeppoSAX. We find that the 8 non-cooling flow clusters
have flat metallicity profiles. On the contrary, a strong enhancement in the
abundance is found in the central regions of the cooling flow clusters. All the
non-cooling flow clusters present evidence of recent merger activity suggesting
that the merger events redistributes efficiently the metal content of the
intracluster medium. For the cooling flow clusters with better statistics and
available optical data (A85, A496, A2029 and Perseus) we have tested whether
the observed abundance excess is due to metals ejected from the galaxies
located in the cluster core. We find that at a resolution > 100 kpc the
observed projected abundance excess profiles are consistent with originating
from a deprojected metal excess distribution tracing the optical light
distribution. In the one case (i.e. Perseus) with higher resolution (~ 50 kpc),
we find that the observed metal abundance excess distribution is broader than
the predicted one. Such a difference can be reconciled if we assume that the
metals have drifted away from their parent ejecting galaxies by a few tens of
kpc, or, alternatively, if we assume that the cluster light profile has become
significantly more centrally peaked because of the formation process of the
central dominant cluster galaxy since the last major merger occurred.

</DOC>
<DOC>
<DOCNO> 120684 </DOCNO>
Deflection of jets induced by jet-cloud & jet-galaxy interactions


  The model first introduced by Raga & Canto (1996) in which astrophysical jets
are deflected on passing through an isothermal high density region is
generalised by taking into account gravitational effects on the motion of the
jet as it crosses the high density cloud. The problem is also generalised for
relativistic jets in which gravitational effects induced by the cloud are
neglected. Two further cases, classical and relativistic, are discussed for the
cases in which the jet is deflected on passing through the interstellar gas of
a galaxy in which a dark matter halo dominates the gravitational potential.
  The criteria for the stability of jets due to the formation of internal
shocks are discussed.

</DOC>
<DOC>
<DOCNO> 121856 </DOCNO>
Observations of Mkn 421 with the CELESTE Experiment


  The CELESTE experiment uses the heliostats of an old solar farm in the French
Pyrenees to detect gamma ray air showers by the atmospheric Cerenkov technique.
Observations of the TeV blazar Markarian 421 have been made with the fully
instrumented CELESTE experiment since December 1999. The detection of gamma ray
emission from this source at energies greater than 50 GeV is presented here. A
comparison is made with the light curve from the CAT experiment at the same
site which shows correlation between the observed gamma ray fluxes and the
detection of short duration flaring episodes.

</DOC>
<DOC>
<DOCNO> 68297 </DOCNO>
SU(3) Flavor Symmetry and CP Violating Rate Differences for Charmless


  We derive several relations between CP violating rate differences
$\Delta(B\to PV) = \Gamma(B\to PV) - \Gamma(\bar B \to \bar P \bar V)$ for
charmless $B\to P V$ decays in the Standard Model using SU(3) flavor symmetry.
It is found that although the relations between branching ratios of $\Delta S =
0$ and $\Delta S = -1$ processes are complicated, there are simple relations
independent of hadronic models between some of the $\Delta S =0$ and $\Delta S
= -1$ rate differences due to the unitarity property of the Kobayashi-Maskawa
matrix, such as $ \Delta(B\to \pi^+ \rho^-) = -\Delta(B\to \pi^+ K^{*-})$,
$\Delta(B\to \pi^- \rho^+) = - \Delta(K^- \rho^+)$. SU(3) breaking effects are
also estimated using factorization approximation. These relations can be tested
at B factories in the near future.

</DOC>
<DOC>
<DOCNO> 119671 </DOCNO>
Evolution in the Clustering of Galaxies for z < 1.0


  Measuring the evolution in the clustering of galaxies over a large redshift
range is a challenging problem. We have developed a new technique which uses
photometric redshifts to measure the angular correlation function in redshift
shells. This novel approach minimizes the galaxy projection effect inherent in
standard angular correlation measurements, and allows for a measurement of the
evolution in the galaxy correlation strength with redshift. In this paper, we
present new results which utilize more accurate photometric redshifts, which
are derived from a multi-band dataset (U,B,R, and I) covering almost two
hundred square arcminutes to B_{AB} ~ 26.5, to quantify the evolution in the
clustering of galaxies for z < 1. We also extend our technique to incorporate
absolute magnitudes, which provides a simultaneous measurement of the evolution
of clustering with both redshift and intrinsic luminosity. Specifically, we
find a gradual decline in the strength of clustering with redshift out to z ~
1, as predicted by semi-analytic models of structure formation. Furthermore, we
find that r_0(z=0) ~ 4.0 h^{-1} Mpc for the predictions of linear theory in an
Omega_0 = 0.1 universe.

</DOC>
<DOC>
<DOCNO> 71560 </DOCNO>
Baryon Masses in the 1/N Expansion


  The masses of baryons and heavy quark baryons are studied analytically in an
expansion in 1/N, SU(3) flavor symmetry breaking and heavy-quark symmetry
breaking. The measured baryon masses are in striking agreement with the 1/N
hierarchy.

</DOC>
<DOC>
<DOCNO> 170543 </DOCNO>
Quantum cryptographic three party protocols


  Due to the impossibility results of Mayers and Lo/Chau it is generally
thought that a quantum channel is cryptographically strictly weaker than
oblivious transfer. In this paper we prove that in a three party scenario a
quantum channel can be strictly stronger than oblivious transfer. With the
protocol introduced in this paper we can completely classify the cryptographic
strength of quantum multi party protocols.

</DOC>
<DOC>
<DOCNO> 10717 </DOCNO>
Hofstadter butterfly and integer quantum Hall effect in three dimensions


  For a three-dimensional lattice in magnetic fields we have shown that the
hopping along the third direction, which normally tends to smear out the Landau
quantization gaps, can rather give rise to a fractal energy spectram akin to
Hofstadter's butterfly when a criterion, found here by mapping the problem to
two dimensions, is fulfilled by anisotropic (quasi-one-dimensional) systems. In
3D the angle of the magnetic field plays the role of the field intensity in 2D,
so that the butterfly can occur in much smaller fields. The mapping also
enables us to calculate the Hall conductivity, in terms of the topological
invariant in the Kohmoto-Halperin-Wu's formula, where each of $\sigma_{xy},
\sigma_{zx}$ is found to be quantized.

</DOC>
<DOC>
<DOCNO> 150891 </DOCNO>
Consistency of Super-Poincare Covariant Superstring Tree Amplitudes


  Using pure spinors, the superstring was recently quantized in a manifestly
ten-dimensional super-Poincar\'e covariant manner and a covariant prescription
was given for tree-level scattering amplitudes. In this paper, we prove that
this prescription is cyclically symmetric and, for the scattering of an
arbitrary number of massless bosons and up to four massless fermions, it agrees
with the standard Ramond-Neveu-Schwarz prescription.

</DOC>
<DOC>
<DOCNO> 99430 </DOCNO>
Topological Representations of Posets


  Earlier an arbitrary poset $P$ was proved to be isomorphic to the collection
of subsets of a space $M$ with two closures which are closed in the first
closure and open in the other. As a space $M$ for this representation an
algebraic dual space $P^*$ was used. Here we extend the theory of algabraic
duality for posets generalizing the notion of an ideal. This approach yields a
sufficient condition for the collection of clopen subsets of a subset of $P^*$
(with respect to induced closures) to be isomorphic to $P$. Applying this
result to certain classes of posets we prove some representation theorems and
get a topological characterization of orthocomplementations.

</DOC>
<DOC>
<DOCNO> 119682 </DOCNO>
Velocity and Mass Functions of Galactic Halos: Evolution and


  We study the distribution functions of mass and circular velocity for dark
matter halos in N-body simulations of the $\Lambda$CDM cosmology, addressing
redshift and environmental dependence. The dynamical range enables us to
resolve subhalos and distinguish them from "distinct" halos. The mass function
is compared to analytic models, and is used to derive the more observationally
relevant circular velocity function. The distribution functions in the velocity
range 100--500 km/s are well fit by a power-law with two parameters, slope and
amplitude. We present the parameter dependence on redshift and provide useful
fitting formulae. The amplitudes of the mass functions decrease with z, but,
contrary to naive expectation, the comoving density of halos of a fixed
velocity ~200 km/s actually increases out to z=5. This is because high-z halos
are denser, so a fixed velocity corresponds to a smaller mass. The slope of the
velocity function at z=0 is as steep as ~ -4, and the mass and velocity
functions of distinct halos steepen with increasing z, while the functions of
subhalos do not steepen with $z$, and become even flatter at z>2. A simple
observable prediction is that the slope of the velocity function of isolated
galaxies is steeper than that of galaxies in groups by as much as unity,
reflecting the density biasing of high-velocity halos. We confirm that the
Press-Schechter approximation typically overestimates the halo mass function by
a factor of ~2, while modified approximations provide improved predictions.

</DOC>
<DOC>
<DOCNO> 68420 </DOCNO>
Discrete Ambiguities in B-Decay CP Asymmetries and the Search for New


  The first measurements of CP violation in the B system will probably extract
$\sin 2\alpha$, $\sin 2\beta$ and $\cos 2\gamma$. Assuming that the CP angles
$\alpha$, $\beta$ and $\gamma$ are the interior angles of the unitarity
triangle, this determines the angle set $(\alpha,\beta,\gamma)$ up to a twofold
discrete ambiguity. The presence of this discrete ambiguity can make the
discovery of new physics difficult: if only one of the two solutions is
consistent with constraints from other measurements in the B and K systems, one
is not sure whether new physics is present or not. I present examples of this
situation, and discuss ways to resolve the discrete ambiguity.

</DOC>
<DOC>
<DOCNO> 101934 </DOCNO>
Piecewise-constant potentials with practically the same fixed-energy


  It has recently been shown that spherically symmetric potentials of finite
range are uniquely determined by the part of their phase shifts at a fixed
energy level $k^2>0$. However, numerical experiments show that two quite
different potentials can produce almost identical phase shifts. It has been
guessed by physicists that such examples are possible only for "less physical"
oscillating and changing sign potentials. In this note it is shown that the
above guess is incorrect: we give examples of four positive spherically
symmetric compactly supported quite different potentials having practically
identical phase shifts. The note also describes a hybrid
stochastic-deterministic method for global minimization used for the
construction of these potentials.

</DOC>
<DOC>
<DOCNO> 9265 </DOCNO>
Superconductivity as a Bose-Einstein condensation?


  Bose-Einstein condensation (BEC) in two dimensions (2D) (e.g., to describe
the quasi-2D cuprates) is suggested as the possible mechanism widely believed
to underlie superconductivity in general. A crucial role is played by nonzero
center-of-mass momentum Cooper pairs (CPs) usually neglected in BCS theory.
Also vital is the unique {\it linear} dispersion relation appropriate to
weakly-coupled "bosonic" CPs moving in the Fermi sea---rather than in vacuum
where the dispersion would be quadratic but only for very strong coupling, and
for which BEC is known to be impossible in 2D.

</DOC>
<DOC>
<DOCNO> 70948 </DOCNO>
Liquid-gas phase transition in nuclear multifragmentation


  The equation of state of nuclear matter suggests that at suitable beam
energies the disassembling hot system formed in heavy ion collisions will pass
through a liquid-gas coexistence region. Searching for the signatures of the
phase transition has been a very important focal point of experimental
endeavours in heavy ion collisions, in the last fifteen years. Simultaneously
theoretical models have been developed to provide information about the
equation of state and reaction mechanisms consistent with the experimental
observables. This article is a review of this endeavour.

</DOC>
<DOC>
<DOCNO> 122318 </DOCNO>
H-alpha Imaging with HST+NICMOS of An Elusive Damped Ly-alpha Cloud at


  Despite previous intensive ground-based imaging and spectroscopic campaigns
and wide-band HST imaging of the z=0.927 QSO 3C336 field, the galaxy that hosts
the damped Ly-alpha system along this line-of-sight has eluded detection. We
present a deep narrow-band H-alpha image of the field of this z=0.656 damped
Ly-alpha absorber, obtained through the F108N filter of NICMOS 1 onboard the
Hubble Space Telescope. The goal of this project was to detect any H-alpha
emission 10 times closer than previous studies to unveil the damped absorber.
We do not detect H-alpha emission between 0.05'' and 6'' (0.24 and 30 $h^{-1}$
kpc) from the QSO, with a 3-sigma flux limit of $3.70 \times 10^{-17} h^{-2}$
erg/s/cm^2 for an unresolved source, corresponding to a star formation rate
(SFR) of $0.3 h^{-2}$ M_sun/yr. This leads to a 3-sigma upper limit of 0.15
M_sun/yr/kpc^2 on the SFR density, or a maximum SFR of 1.87 M_sun/yr assuming a
disk of 4 kpc in diameter. This result adds to the number of low redshift
damped Ly-alpha absorbers that are not associated with the central regions of
Milky-Way-like disks. Damped Ly-alpha absorption can arise from high density
concentrations in a variety of galactic environments including some that,
despite their high local HI densities, are not conducive to widespread star
formation.

</DOC>
<DOC>
<DOCNO> 123071 </DOCNO>
The ROSAT-ESO Flux Limited X-Ray (REFLEX) Galaxy Cluster Survey I: The


  We describe the construction of an X-ray flux-limited sample of galaxy
clusters, the REFLEX survey catalogue, to be used for cosmological studies. The
survey is based on the ROSAT All-Sky Survey and on extensive follow-up
observations conducted in the frame of an ESO key program. In the paper we
document the process by which the primary cluster candidate catalogue is
constructed prior to the optical follow-up observations. We describe the
reanalysis of the RASS source catalogue which enables us to impose a proper
flux limit cut to the X-ray source list without introducing a severe bias
against extended sources. We discuss the correlation of the X-ray and optical
(COSMOS) data to find galaxy density enhancements at the RASS X-ray source
positions and the further evaluation of the nature of these cluster candidates.
Based also on the results of the follow-up observations we provide a
statistical analysis of the completeness and contamination of the final cluster
sample and show results on the cluster number counts. The final sample of
identified X-ray clusters reaches a flux limit of 3e-12 erg s-1 cm-2 in the 0.1
- 2.4 keV band and comprises 452 clusters. The results imply a completeness of
the REFLEX cluster sample well in excess of 90% and a contamination by
non-cluster X-ray sources of less than 9%, an accuracy sufficient for the use
of this cluster sample for cosmological tests.

</DOC>
<DOC>
<DOCNO> 170007 </DOCNO>
Performing Quantum Measurement in Suitably Entangled States Originates


  We introduce a local concept of speed-up applicable to intermediate stages of
a quantum algorithm. We use it to analyse the complementary roles played by
quantum parallel computation and quantum measurement in yielding the speed-up.
A severe conflict between there being a speed-up and the many worlds
interpretation is highlighted.

</DOC>
<DOC>
<DOCNO> 152036 </DOCNO>
Residual Representations of Spacetime


  Spacetime is modelled by binary relations - by the classes of the
automorphisms $\GL(\C^2)$ of a complex 2-dimensional vector space with respect
to the definite unitary subgroup $\U(2)$. In extension of Feynman propagators
for particle quantum fields representing only the tangent spacetime structure,
global spacetime representations are given, formulated as residues using
energy-momentum distributions with the invariants as singularities. The
associatated quantum fields are characterized by two invariant masses - for
time and position - supplementing the one mass for the definite unitary
particle sector with another mass for the indefinite unitary interaction sector
without asymptotic particle interpretation.

</DOC>
<DOC>
<DOCNO> 84564 </DOCNO>
A Generalized Equivalence Principle


  Gauge field theories may quite generally be defined as describing the
coupling of a matter-field to an interaction-field, and they are suitably
represented in the mathematical framework of fiber bundles. Their underlying
principle is the so-called gauge principle, which is based on the idea of
deriving the coupling structure of the fields by satisfying a postulate of
local gauge covariance. The gauge principle is generally considered to be
sufficient to define the full structure of gauge-field theories. This paper
contains a critique of this usual point of view: firstly, by emphazising an
gauge theoretic conventionalism which crucially restricts the conceptual role
of the gauge principle and, secondly, by introducing a new generalized
equivalence principle - the identity of inertial and field charge (as
generalizations of inertial and gravitational mass) - in order to give a
conceptual justification for combining the equations of motion of the
matter-fields and the field equations of the interaction-fields.

</DOC>
<DOC>
<DOCNO> 117391 </DOCNO>
An asymmetric relativistic model for classical double radio sources


  There is substantial observational evidence against the symmetric
relativistic model of FRII radio sources. An asymmetric relativistic model is
proposed which takes account of both relativistic effects and
intrinsic/environmental asymmetries to explain the structural asymmetries of
their radio lobes. A key parameter of the model is the jet-side of the double
sources, which is estimated for 80% of the FRII sources in the 3CRR complete
sample. Statistical analyses of the properties of these sources show that the
asymmetric model is in agreement with a wide range of observational data, and
that the relativistic and intrinsic asymmetry effects are of comparable
importance. Intrinsic/environmental asymmetry effects are more important at
high radio luminosities and small physical scales. The mean translational speed
of the lobes is found to be 0.11c, consistent with the speeds found from
spectral ageing arguments. According to a Gaussian model, the standard
deviation of lobe speeds is 0.04c. The results are in agreement with an
orientation-based unification scheme in which the critical angle separating the
radio galaxies from quasars is about 45 degrees.

</DOC>
<DOC>
<DOCNO> 118291 </DOCNO>
Space VLBI Observations of 3C 279 at 1.6 and 5 GHz


  We present the first VLBI Space Observatory Programme (VSOP) observations of
the gamma-ray blazar 3C 279 at 1.6 and 5 GHz. The combination of the VSOP and
VLBA-only images at these two frequencies maps the jet structure on scales from
1 to 100 mas. On small angular scales the structure is dominated by the quasar
core and the bright secondary component `C4' located 3 milliarcseconds from the
core (at this epoch). On larger angular scales the structure is dominated by a
jet extending to the southwest, which at the largest scale seen in these images
connects with the smallest scale structure seen in VLA images. We have
exploited two of the main strengths of VSOP: the ability to obtain
matched-resolution images to ground-based images at higher frequencies and the
ability to measure high brightness temperatures. A spectral index map was made
by combining the VSOP 1.6 GHz image with a matched-resolution VLBA-only image
at 5 GHz from our VSOP observation on the following day. The spectral index map
shows the core to have a highly inverted spectrum, with some areas having a
spectral index approaching the limiting value for synchrotron self-absorbed
radiation of 2.5. Gaussian model fits to the VSOP visibilities revealed high
brightness temperatures (>10^{12} K) that are difficult to measure with
ground-only arrays. An extensive error analysis was performed on the brightness
temperature measurements. Most components did not have measurable brightness
temperature upper limits, but lower limits were measured as high as 5x10^{12}
K. This lower limit is significantly above both the nominal inverse Compton and
equipartition brightness temperature limits. The derived Doppler factor,
Lorentz factor, and angle to the line-of-sight in the case of the equipartition
limit are at the upper end of the range of expected values for EGRET blazars.

</DOC>
<DOC>
<DOCNO> 71614 </DOCNO>
A Gaussian Sum-Rules Analysis of Scalar Glueballs


  Although marginally more complicated than the traditional Laplace sum-rules,
Gaussian sum-rules have the advantage of being able to probe excited and ground
states with similar sensitivity. Gaussian sum-rule analysis techniques are
applied to the problematic scalar glueball channel to determine masses, widths
and relative resonance strengths of low-lying scalar glueball states
contributing to the hadronic spectral function. A feature of our analysis is
the inclusion of instanton contributions to the scalar gluonic correlation
function. Compared with the next-to-leading Gaussian sum-rule, the analysis of
the lowest-weighted sum-rule (which contains a large scale-independent
contribution from the low energy theorem) is shown to be unreliable because of
instability under QCD uncertainties. However, the presence of instanton effects
leads to approximately consistent mass scales in the lowest weighted and
next-lowest weighted sum-rules. The analysis of the next-to-leading sum-rule
demonstrates that a single narrow resonance model does not provide an adequate
description of the hadronic spectral function. Consequently, we consider a wide
variety of phenomenological models which distribute resonance strength over a
broad region---some of which lead to excellent agreement between the
theoretical prediction and phenomenological models. Including QCD
uncertainties, our results indicate that the hadronic contributions to the
spectral function stem from a pair of resonances with masses in the range
0.8--1.6 GeV, with the lighter of the two potentially having a large width.

</DOC>
<DOC>
<DOCNO> 67703 </DOCNO>
Elements of Baryogenesis


  Basic ingredients of the theory of baryogenesis are reviewed with emphasis on
out-of-equilibrium decays of heavy particles. The present use of kinetic theory
is explained and some attempts to go beyond the classical Boltzmann equations
are discussed.

</DOC>
<DOC>
<DOCNO> 120370 </DOCNO>
Luminosities and pulsational properties of RR Lyrae variables in the bar


  New B,V CCD photometry in the standard Johnson system is presented for two
fields (A and B) located close to the bar of the LMC and contained in fields 6
and 13 of the MACHO microlensing experiment. We detected 128 RR Lyrae variables
in the two areas and obtained full coverage of the B and V light curves for 93
and 107 variables, respectively. The average apparent luminosity of the RR
Lyrae's with complete V and B light curves is <V(RR)>= 19.352+/-0.023 (52
stars) and <B(RR)>=19.762+/-0.023 (48 stars) in field A, and
<V(RR)=19.314+/-0.025 (41 stars) and <B(RR)>=19.656+/-0.030 in field B (33
stars). The average apparent luminosity of the clump stars in the same fields
is about 0.12 mag brighter than the RR Lyrae level (<V(clump)>=19.223+/-0.003
and 19.200+/-0.003, in field A (5345 stars) and B (3639 stars), respectively).
An estimate of the reddening was obtained from the colors of the edges of the
instability strip defined by the RR Lyrae variables: E(B-V)=0.08+/-0.02, and
0.06+/-0.02 mag in field A and B. When coupled with the apparent luminosities
of the RR Lyrae's and the absolute magnitude derived from the Baade-Wesselink
and the statistical parallaxes methods these new reddening estimates lead to
distance modulus for the LMC of 18.40+/-0.15. The present determination of the
V luminosity of the clump when combined with OGLE-II <V-I>o=0.89 mag, and
corrected back to our new reddening values moves the clump distance modulus of
the LMC to 18.42+/-0.07. All these values are only 1 sigma shorter than
provided by the Population I distance indicators (e.g. the Cepheids), and allow
to reconcile the short and long distance scale on a common value for the
distance modulus of the LMC of 18.50+/-0.07.

</DOC>
<DOC>
<DOCNO> 70777 </DOCNO>
Non-Thermal Production of WIMPs and the Sub-Galactic Structure of the


  There is increasing evidence that conventional cold dark matter (CDM) models
lead to conflicts between observations and numerical simulations of dark matter
halos on sub-galactic scales. Spergel and Steinhardt showed that if the CDM is
strongly self-interacting, then the conflicts disappear. However, the
assumption of strong self-interaction would rule out the favored candidates for
CDM, namely weakly interacting massive particles (WIMPs), such as the
neutralino. In this paper we propose a mechanism of non-thermal production of
WIMPs and study its implications on the power spectrum. We find that the
non-vanishing velocity of the WIMPs suppresses the power spectrum on small
scales compared to what it obtained in the conventional CDM model. Our results
show that, in this context, WIMPs as candidates for dark matter can work well
both on large scales and on sub-galactic scales.

</DOC>
<DOC>
<DOCNO> 119431 </DOCNO>
Voids in the LCRS versus CDM Models


  We have analyzed the distribution of void sizes in the two-dimensional slices
of the Las Campanas Redshift Survey (LCRS). Fourteen volume-limited subsamples
were extracted from the six slices to cover a large part of the survey and to
test the robustness of the results against cosmic variance. Thirteen samples
were randomly culled to produce homogeneously selected samples. We then studied
the relationship between the cumulative area covered by voids and the void size
as a property of the void hierarchy. We find that the distribution of void
sizes scales with the mean galaxy separation, $\lambda$. In particular, we find
that the size of voids covering half of the area is given by $D_{med} \approx
\lambda + (12\pm3) \h^{-2}$Mpc. Next, by employing an environmental density
threshold criterion to identify mock galaxies, we were able to extend this
analysis to mock samples from dynamical $n$-body simulations of Cold Dark
Matter (CDM) models. To reproduce the observed void statistics, overdensity
thresholds of $\delta_{th} \approx 0 ... 1$ are necessary. We have compared
standard (SCDM), open (OCDM), vacuum energy dominated ($\Lambda$CDM), and
broken scale invariant CDM models (BCDM): we find that both the void coverage
distribution and the two-point correlation function provide important and
complementary information on the large-scale matter distribution. The
dependence of the void statistics on the threshold criterion for the mock
galaxy indentification shows that the galaxy biasing is more crucial for the
void size distribution than are differences between the cosmological models.

</DOC>
<DOC>
<DOCNO> 101906 </DOCNO>
Hua type integrals over unitary groups and over projective limits of


  We discuss some natural maps from a unitary group U(n) to a smaller group
U(n-m) (these maps are versions of the Livshic characteristic function).
  We calculate explicitly the direct images of the Haar measure under some
maps.
  We evaluate some matrix integrals over classical groups and some symmetric
spaces (values of the integrals are products of Gamma-functions). These
integrals generalize Hua Loo Keng integrals. We construct inverse limits of
unitary groups equipped with analogues of the Haar measure and evaluate some
integrals over these inverse limits.

</DOC>
<DOC>
<DOCNO> 118214 </DOCNO>
The Formation and Fragmentation of Primordial Molecular Clouds


  Many questions in physical cosmology regarding the thermal history of the
intergalactic medium, chemical enrichment, reionization, etc. are thought to be
intimately related to the nature and evolution of pregalactic structure. In
particular the efficiency of primordial star formation and the primordial IMF
are of special interest. We present results from high resolution
three--dimensional adaptive mesh refinement simulations that follow the
collapse of primordial molecular clouds and their subsequent fragmentation
within a cosmologically representative volume. Comoving scales from 128 kpc
down to 1 pc are followed accurately. Dark matter dynamics, hydrodynamics and
all relevant chemical and radiative processes (cooling) are followed
self-consistently for a cluster normalized CDM structure formation model.
Primordial molecular clouds with ~10^5 solar masses are assembled by mergers of
multiple objects that have formed hydrogen molecules in the gas phase with a
fractional abundance of ~10^-4. As the subclumps merge cooling lowers the
temperature to ~200 Kelvin in a `cold pocket' at the center of the halo. Within
this cold pocket, a quasi-hydrostatically contracting core with ~200 solar mass
and number densities > 10^5 cm^-3 is found. We find that less than 1% of the
primordial gas in such small scale structures cools and collapses to
sufficiently high densities to be available for primordial star formation.
Furthermore, it is worthwhile to note that this study achieved the highest
dynamic range covered by structured adaptive mesh techniques in cosmological
hydrodynamics to date.

</DOC>
<DOC>
<DOCNO> 84876 </DOCNO>
The classical regime of a quantum universe obtained through a functional


  The functional method, introduced to deal with systems endowed with a
continuous spectrum, is used to study the problem of decoherence and
correlations in a simple cosmological model.

</DOC>
<DOC>
<DOCNO> 68304 </DOCNO>
Features of particle multiplicities and strangeness production in


  A systematic study is performed of fully integrated particle multiplicities
in central Au-Au and Pb-Pb collisions at beam momenta of 1.7A GeV, 11.6A GeV
(Au-Au) and 158$A$ GeV (Pb-Pb) by using a statistical-thermal model. The close
similarity of the colliding systems makes it possible to study heavy ion
collisions under definite initial conditions over a range of centre-of-mass
energies covering more than one order of magnitude. In order to further study
the behaviour of strangeness production, an updated study of Si-Au collisions
at 14.6A GeV is also presented. The data analysis has been performed with two
completely independent numerical algorithms giving closely consistent results.
We conclude that a thermal model description of particle multiplicities, with
additional strangeness suppression, is possible for each energy. The degree of
chemical equilibrium of strange particles and the relative production of
strange quarks with respect to u and d quarks are higher than in e+e-, pp and
ppbar collisions at comparable and even at lower energies. The behaviour of
strangeness production as a function of centre-of-mass energy and colliding
system is presented and discussed. The average energy per hadron in the
comoving frame is close to 1 GeV per hadron despite the fact that the energy
increases more than 10-fold.

</DOC>
<DOC>
<DOCNO> 102602 </DOCNO>
The Q-Picard group of the moduli space of curves in positive


  In this note, we prove that the Q-Picard group of the moduli space of
n-pointed stable curves of genus g over an algebraically closed field is
generated by the tautological classes. We also prove that the cycle map to the
2nd etale cohomology group is bijective.

</DOC>
<DOC>
<DOCNO> 10456 </DOCNO>
Slow crossover in YbXCu4 intermediate valence compounds


  We compare the results of measurements of the magnetic susceptibility Chi(T),
the linear coefficient of specific heat Gamma(T)=C(T)/T and 4f occupation
number nf(T) for the intermediate valence compounds YbXCu4 (X = Ag, Cd, In, Mg,
Tl, Zn) to the predictions of the Anderson impurity model, calculated in the
non-crossing approximation (NCA). The crossover from the low temperature Fermi
liquid state to the high temperature local moment state is substantially slower
in the compounds than predicted by the NCA; this corresponds to the
''protracted screening'' recently predicted for the Anderson Lattice. We
present results for the dynamic susceptibility, measured through neutron
scattering experiments, to show that the deviations between theory and
experiment are not due to crystal field effects, and we present
x-ray-absorption fine-structure (XAFS) results that show the local crystal
structure around the X atoms is well ordered, so that the deviations probably
do not arise from Kondo Disorder. The deviations may correlate with the
background conduction electron density, as predicted for protracted screening.

</DOC>
<DOC>
<DOCNO> 118306 </DOCNO>
Neutron Star Structure and the Equation of State


  The structure of neutron stars is considered from theoretical and
observational perspectives. We demonstrate an important aspect of neutron star
structure: the neutron star radius is primarily determined by the behavior of
the pressure of matter in the vicinity of nuclear matter equilibrium density.
In the event that extreme softening does not occur at these densities, the
radius is virtually independent of the mass and is determined by the magnitude
of the pressure. For equations of state with extreme softening, or those that
are self-bound, the radius is more sensitive to the mass. Our results show that
in the absence of extreme softening, a measurement of the radius of a neutron
star more accurate than about 1 km will usefully constrain the equation of
state. We also show that the pressure near nuclear matter density is primarily
a function of the density dependence of the nuclear symmetry energy, while the
nuclear incompressibility and skewness parameters play secondary roles.
  In addition, we show that the moment of inertia and the binding energy of
neutron stars, for a large class of equations of state, are nearly universal
functions of the star's compactness. These features can be understood by
considering two analytic, yet realistic, solutions of Einstein's equations,
due, respectively, to Buchdahl and Tolman. We deduce useful approximations for
the fraction of the moment of inertia residing in the crust, which is a
function of the stellar compactness and, in addition, the presssure at the
core-crust interface.

</DOC>
<DOC>
<DOCNO> 68825 </DOCNO>
The Quest for Quantum Gravity: Testing Times for Theories?


  I discuss some theoretical ideas concerning the representation of quantum
gravity as a Lorentz-symmetry-violating `medium' with non-trivial optical
properties, which include a refractive index in `vacuo' and stochastic effects
associated with a spread in the arrival times of photons, growing linearly with
the photon energy. Some of these properties may be experimentally detectable in
future satellite facilities (e.g. GLAST or AMS), using as probes light from
distant astrophysical sources such as gamma ray bursters. I also argue that
such linear violations of Lorentz symmetry may not always be constrained by
ultra-high-energy cosmic-ray data, as seems to be the case with a specific
(stringy) model of space-time foam.

</DOC>
<DOC>
<DOCNO> 84946 </DOCNO>
Boson stars driven to the brink of black hole formation


  We present a study of black hole threshold phenomena for a self-gravitating,
massive complex scalar field in spherical symmetry. We construct Type I
critical solutions dynamically by tuning a one-parameter family of initial data
composed of a boson star and a massless real scalar field. The real field is
used to perturb the boson star via a gravitational interaction which results in
a {\em significant} transfer of energy. The resulting critical solutions, which
show great similarity with unstable boson stars, persist for a finite time
before dispersing or forming a black hole. We extend the stability analysis of
Gleiser and Watkins [Nucl. Phys. B319, 733 (1989)], providing a method for
calculating the radial dependence of boson star modes of nonzero frequency. We
find good agreement between our critical solutions and boson star modes. For
critical solutions less than 90% of the maximum boson star mass $M_{\rm max}
\simeq 0.633 M_{Pl}^2/m$, a small halo of matter appears in the tail of the
solution. This halo appears to be an artifact of the collision between the
original boson star and the real field, and does not belong to the true
critical solution. It seems that unstable boson stars are unstable to dispersal
in addition to black hole formation. Given the similarity in macroscopic
stability between boson and neutron stars, we suggest that neutron stars at or
beyond the point of instability may also be unstable to explosion.

</DOC>
<DOC>
<DOCNO> 8927 </DOCNO>
Bak-Sneppen model near zero dimension


  We consider the Bak--Sneppen model near zero dimension where the avalanche
exponent $\tau$ is close to 1 and the exponents $\mu$ and $\sigma$ are close to
0. We demonstrate that $\tau-1=\mu-\sigma=\exp\{-\mu^{-1}-\gamma+...\}$ in this
limit, where $\gamma$ is the Euler's constant. The avalanche hierarchy equation
is rewritten in a form that makes possible to find the relation between the
critical exponents $\sigma$ and $\mu$ with high accuracy. We obtain new, more
precise, values of the critical exponents for the 1D and 2D Bak-Sneppen model
and for the 1D anisotropic Bak-Sneppen model.

</DOC>
<DOC>
<DOCNO> 9652 </DOCNO>
Ultrametric space cut instead of 2d one in 2d quantum field models


  It is possible to formulate 2d field theory on the ultrametric space with the
free correlators identical to 2d correlators and the same potential. Such model
should carry some features of original model for scale invariant theories. For
the case of strings and 2d conformal models it is possible to derive exact
results. It is possible to investigate not only bulk structure (phase
transition points) of theory, but sometimes also correlators. Such ultrametric
models could be naturally expressed via Random energy model and directed
polymer on Cayley tree.

</DOC>
<DOC>
<DOCNO> 152232 </DOCNO>
Tachyon Condensation in Large Magnetic Fields with Background


  We discuss the problem of tachyon condensation in the framework of background
independent open string field theory. We show, in particular, that the
computation of the string field theory action simplifies considerably if one
looks at closed string backgrounds with a large B field, and can be carried out
exactly for a generic tachyon profile. We confirm previous results on the form
of the exact tachyon potential, and we find, within this framework, solitonic
solutions which correspond to lower dimensional unstable branes.

</DOC>
<DOC>
<DOCNO> 10851 </DOCNO>
Parity Effect in Mesoscopic and Nanoscopic Superconducting Particles


  Superconductivity in small metallic specimens is studied with regard to the
size dependence of the "parity gap" (Delta_P), a parameter distinguishing
between the energy of even and odd number of electrons in the granule. Delta_P
is shown to be an increasing function of level spacing delta. The energy gap of
superconductor Delta, on the other hand, decreases with increasing delta and
vanishes at delta=delta_c which is of the order of Delta. However, nonzero
value of Delta_P persists above delta_c in a "gapless"
superconducting-insulating state. Level degeneracy in small specimens having
perfect geometry changes the size dependence of the parity gap, the Josephson
effect, and flux quantization. Parity gap is evaluated using an interpolation
procedure between the continuum limit (delta<<Delta), the moderate mesoscopic
regime (delta ~ Delta), and the nanoscopic scale (delta>>Delta), for which an
exact solution to the pairing problem is provided with the numeric
diagonalization of system Hamiltonian in a small metallic cluster.

</DOC>
<DOC>
<DOCNO> 80704 </DOCNO>
RI/MOM Renormalization Window and Goldstone Pole Contamination


  We perform a comparative study of the ratio of lattice (Wilson fermion)
renormalization constants Z_P/Z_S, obtained non-perturbatively from the RI/MOM
renormalization conditions and from Ward Identities of on- and off-shell
Green's functions. The off-shell Ward Identity used in this work relies on
correlation functions with non-degenerate quark masses. We find that, due to
discretization effects, there is a 10-15% discrepancy between the two Ward
Identity determinations at current bare couplings (beta values). The RI/MOM
result is in the same range and has a similar systematic error of 10-15%. Thus,
contrary to a previous claim, the contamination of the RI/MOM result from the
presence of a Goldstone pole at scales of about 2 GeV is subdominant, compared
to finite cutoff effects.

</DOC>
<DOC>
<DOCNO> 70208 </DOCNO>
Dissipation and quantization


  We show that the dissipation term in the Hamiltonian for a couple of
classical damped-amplified oscillators manifests itself as a geometric phase
and is actually responsible for the appearance of the zero point energy in the
quantum spectrum of the 1D linear harmonic oscillator. We also discuss the
thermodynamical features of the system. Our work has been inspired by 't Hooft
proposal according to which information loss in certain classical systems may
lead to ``an apparent quantization of the orbits which resembles the quantum
structure seen in the real world".

</DOC>
<DOC>
<DOCNO> 178718 </DOCNO>
The three- and four-nucleon systems from chiral effective field theory


  Recently developed chiral nucleon-nucleon (NN) forces at next-to-leading
order (NLO) that describe NN phase shifts up to about 100 MeV fairly well have
been applied to 3N and 4N systems. Faddeev-Yakubovsky equations have been
solved rigorously. The chiral NLO forces depend on a momentum cut-off \Lambda
lying between 540-600 MeV/c. The resulting 3N and 4N binding energies are in
the same range as found using standard NN potentials. In additon, low-energy 3N
scattering observables are very well reproduced like for standard NN forces.
Surprisingly, the long standing A_y-puzzle is resolved at NLO. The cut-off
dependence of the scattering observables is rather mild.

</DOC>
<DOC>
<DOCNO> 69515 </DOCNO>
Charged Higgs decays in models with singlet neutrino in large extra


  In models with large extra dimensions and TeV scale quantum gravity, small
(Dirac) neutrino masses can be obtained naturally if the right-handed neutrino
propagates in the extra dimensions. In this scenario, with 2 Higgs doublets, we
show that the decay of charged Higgs into {\em left-handed} charged lepton (say
\tau) and right-handed neutrino can be significantly enhanced, with O(1)
branching ratio, due to the large number of Kaluza-Klein states of the
right-handed neutrino. Since \tau's from the standard decay of charged Higgs
are {\em right-handed}, the above novel charged Higgs decay can provide a
distinctive signature of these models at hadron/lepton colliders. Similarly,
top quark decays to b \mu^+ \nu, b \tau^+ \nu through virtual charged Higgs can
be enhanced.

</DOC>
<DOC>
<DOCNO> 68458 </DOCNO>
Photon-Photon and Pomeron-Pomeron Processes in Peripheral Heavy Ion


  We estimate the cross sections for the production of resonances, pion pairs
and a central cluster of hadrons in peripheral heavy-ion collisions through
two-photon and double-pomeron exchange, at energies that will be available at
RHIC and LHC. The effect of the impact parameter in the diffractive reactions
is introduced, and imposing the condition for realistic peripheral collisions
we verify that in the case of very heavy ions the pomeron-pomeron contribution
is indeed smaller than the electromagnetic one. However, they give a
non-negligible background in the collision of light ions. This diffractive
background will be more important at RHIC than at LHC.

</DOC>
<DOC>
<DOCNO> 101951 </DOCNO>
Equations of Parametric Surfaces via Syzygies


  The revised version has two additional references and a shorter proof of
Proposition 5.7. This version also makes numerous small changes and has an
appendix containing a proof of the degree formula for a parametrized surface.

</DOC>
<DOC>
<DOCNO> 71783 </DOCNO>
The general QCD parametrization and the 1/N(c) expansion: A comparison


  A comparison is presented of the two methods mentioned in the title for
treating hadron properties in QCD.While the general parametrization is derived
exactly from real QCD,the equivalence of the large N(c) description to real QCD
with 3 colors,is questionable.The reason why in some cases the large N(c)
method approximately works (while in others does not) is clarified.

</DOC>
<DOC>
<DOCNO> 178954 </DOCNO>
Kaon production at subthreshold and threshold energies


  We summarize what we have learnt about the kaon production in nucleus-nucleus
collisions in the last decade. We will address three questions: a) Is the $K^+$
production sensitive to the nuclear equation of state? b) How can it happen
that at the same excess energy the same number of $K^+$ and $K^-$ are produced
in heavy ion collisions although the elementary cross section in pp collisions
differs by orders of magnitudes? and c) Why kaons don't flow?

</DOC>
<DOC>
<DOCNO> 10750 </DOCNO>
Energy separation of single-particle and continuum states in a S=1/2


  Inelastic neutron scattering is used to study transverse-polarized magnetic
excitations in the quasi-one-dimensional S=1/2 antiferromagnet BaCu_2Si_2O_7,
where the saturation value for the N\'eel order parameter is $m_0=0.12 \mu_{\rm
B}$ per spin. At low energies the spectrum is totally dominated by
resolution-limited spin wave-like excitations. An excitation continuum sets in
above a well-defined threshold frequency. Experimental results are discussed in
the context of current theories for weakly-interacting quantum half-integer
spin chains.

</DOC>
<DOC>
<DOCNO> 71729 </DOCNO>
Neutrino Oscillations Induced by Two-loop Radiative Effects


  Phenomena of neutrino oscillations are discussed on the basis of two-loop
radiative neutrino mechanism. Neutrino mixings are experimentally suggested to
be maximal in both atmospheric and solar neutrino oscillations. By using $L_e -
L_\mu - L_\tau$ ($\equiv L^\prime$)-conservation, which, however, only ensures
the maximal solar neutrino mixing, we find that two-loop radiative mechanism
dynamically generates the maximal atmospheric neutrino mixing and that the
estimate of $\Delta m^2_\odot/\Delta m^2_{atm} \sim\epsilon m_e/m_\tau$
explains $\Delta m^2_\odot/\Delta m^2_{atm} \ll 1$ because of $m_e/m_\tau \ll
1$, where $\epsilon$ measures the breaking of the $L^\prime$-conservation.
Together with $\Delta m^2_{atm} \approx 3\times 10^{-3}$ eV$^2$, this estimate
yields $\Delta m^2_\odot \sim 10^{-7}$ eV$^2$ for $\epsilon \sim 0.1$, which
corresponds to the LOW solution to the solar neutrino problem. Neutrino mass
scale is given by $(16\pi^2)^{-2} m_em_\tau /M$ ($M \sim$ 1 TeV), which is of
order 0.01 eV.

</DOC>
<DOC>
<DOCNO> 70288 </DOCNO>
The Theory of the Nucleon Spin


  I discuss two topics of current interest in the study of the spin structure
of the nucleon. First, I discuss whether there is a sum rule for the components
of the nucleon's angular moments. Second, I discuss the measurement of the
nucleon's transversity distribution in light of recent results reported by the
HERMES collaboration at DESY.

</DOC>
<DOC>
<DOCNO> 10602 </DOCNO>
Stripes in the Ising Limit of Models for the Cuprates


  The hole-doped standard and extended t-J models on ladders with anisotropic
Heisenberg interactions are studied computationally in the interval $0.0 \leq
\lambda \leq 1.0$ ($\lambda=0$, Ising; $\lambda=1$, Heisenberg). It is shown
that the approximately half-doped stripes recently discussed at $\lambda=1$
survive in the anisotropic case ($\lambda$$<$1.0), particularly in the
``extended'' model. Due to the absence of spin fluctuations in the Ising limit
and working in the rung basis, a simple picture emerges in which the stripe
structure can be mostly constructed from the solution of the t-J model on
chains. A comparison of results in the range $0.0 \leq \lambda \leq 1.0$
suggests that this picture is valid up to the Heisenberg limit.

</DOC>
<DOC>
<DOCNO> 13044 </DOCNO>
Exact, numerical, and mean field behavior of a dimerizing lattice in one


  The thermodynamics and dynamics of a one dimensional dimer-forming anharmonic
model is studied in the classical limit. This model mimics the behavior of
materials with a Peierls instability. Specific heat, correlation length, and
order parameter are calculated three ways: (a) by mean field approximation, (b)
by numerical molecular dynamics simulation, and (c) by an exact transfer matrix
method. The single-particle spectrum (velocity-velocity correlation function)
is found numerically and in mean field theory.

</DOC>
<DOC>
<DOCNO> 8771 </DOCNO>
Diabolical points in the magnetic spectrum of Fe_8 molecules


  The magnetic molecule Fe_8 has been predicted and observed to have a rich
pattern of degeneracies in its spectrum as an external magnetic field is
varied. These degeneracies have now been recognized to be diabolical points.
This paper analyzes the diabolicity and all essential properties of this system
using elementary perturbation theory. A variety of arguments is gievn to
suggest that an earlier semiclassical result for a subset of these points may
be exactly true for arbitrary spin

</DOC>
<DOC>
<DOCNO> 116653 </DOCNO>
Multidimensional Mesh Approaches to Calculations of Atoms and Diatomic


  Fully numerical mesh solutions of 2D and 3D quantum equations of Schroedinger
and Hartree-Fock type allow us to work with wavefunctions which possess a very
flexible geometry. This flexibility is especially important for calculations of
atoms and molecules in strong external fields where neither the external field
nor the internal interactions can be considered as a perturbation. In the
framework of this method we present various approaches to calculations of
quasi-steady states of these systems in strong electric fields. These
approaches are aimed at obtaining precise complex wavefunctions and
corresponding eigenvalues in the form E = E_0 - i\Gamma/2, where E_0 is the
real part of the energy and the value \Gamma/2 determines the lifetime of the
state in relation to escape of electrons from the system. The applications for
single-electron systems include correct solutions of the Schroedinger equation
for the H_2^+ ion (energies and decay rates) and the hydrogen atom in strong
parallel electric and magnetic fields. Some results for the helium atom in
strong electric fields are announced.

</DOC>
<DOC>
<DOCNO> 118501 </DOCNO>
Is the [CO] index an age indicator for star forming galaxies?


  The classical [CO] index, i.e. the strength of the CO first overtone
absorption bands starting at 2.29 micron, is sometimes used to constrain the
maximum age of star formation events in galaxies. In this paper we critically
analyze
  - theoretical models which could predict either a factor of >2 drop or a
pronounced increase of [CO] at ages older than 100 Myr, depending on the
evolutionary tracks one adopts
  - observational data for young clusters in the LMC which do not show any
strong relationship between the CO index and cluster age.
  The above scenario indicates that the value of [CO] does not provide a
reliable tool for estimating the age of stellar populations older than about 10
Myr, i.e. after the first red supergiants have been formed.
  The contradictory results of theoretical models reflect problems in treating
the evolution along the Asymptotic Giant Branch (AGB). In particular, those
evolutionary synthesis models using stellar tracks which do not include the
thermal pulsing AGB phase produce too weak CO features at 100-1000 Myr, i.e. in
the range of ages when the near infrared emission is dominated by thermal
pulsing AGB stars.

</DOC>
<DOC>
<DOCNO> 120028 </DOCNO>
The Caltech Faint Galaxy Redshift Survey XII: Clustering of Galaxies


  A clustering analysis is performed on two samples of $\sim 600$ faint
galaxies each, in two widely separated regions of the sky, including the Hubble
Deep Field. One of the survey regions is configured so that some galaxy pairs
span angular separations of up to 1 deg. The median redshift is $z_{med}\approx
0.55$. Strong clustering is obvious, with every pencil-beam field containing a
handful of narrow redshift-space features, corresponding to galaxy structures
with sizes of 5 to 20 Mpc. The structures are not obviously organized on
planes, though one prominent, colinear triplet of structures is observed,
spanning $\sim 20$ Mpc. This may be evidence of a filament. A galaxy--galaxy
correlation function calculation is performed. No significant evolution of
clustering (relative to stable clustering) is found in the redshift range
0.3<z<1.0. This is not surprising, since uncertainties in the correlation
amplitude estimated from surveys like these are large; field-to-field
variations and covariances between data points are both shown to be
significant. Consistent with other studies in this redshift range, the
galaxy--galaxy correlation length is found to be somewhat smaller than that
predicted from local measurements and an assumption of no evolution. Galaxies
with absorption-line-dominated spectra show much stronger clustering at
distances of <2 Mpc than typical field galaxies. There is some evidence for
weaker clustering at intermediate redshift than at low redshift, when the
results presented here are compared with surveys of the local Universe. In
subsets of the data, the measured pairwise velocity dispersion of galaxies
ranges from 200 to $600 km s^{-1}$, depending on the properties of the dominant
redshift structures in each subset.

</DOC>
<DOC>
<DOCNO> 100401 </DOCNO>
A fixed point formula for loop group actions


  We express the index of the Dirac operator on symplectic quotients of a
Hamiltonian loop group manifold with proper moment map in terms of fixed point
data.

</DOC>
<DOC>
<DOCNO> 40184 </DOCNO>
The Next Linear Collider Klystron Development Program*


  Klystrons capable of 75 MW output power at 11.4 GHz have been under
development at SLAC for the last decade. The work has been part of the program
to realize all the components necessary for the construction of the Next Linear
Collider (NLC). The effort has produced a family of solenoid-focused 50 MW
klystrons, which are currently powering a 0.5 GeV test accelerator at SLAC and
several test stands, where high power components are evaluated and fundamental
research is performed studying rf breakdown and dark current production.
Continuing development has resulted in a Periodic Permanent Magnet (PPM)
focused 50 MW klystron, tested at SLAC and subsequently contracted for
manufacture by industry in England and Japan. A 75 MW version of that PPM
klystron was built at SLAC and reached 75 MW, with 2.8 microsecond pulses.
Based on this design, a prototype 75 MW klystron, designed for low-cost
manufacture, is currently under development at SLAC, and will eventually be
procured from industry in modest quantities for advanced NLC tests. Beyond
these developments, the design of Multiple Beam Klystrons (MBKs) is under study
at SLAC. MBKs offer the possibility of considerably lower modulator costs by
producing comparable power to the klystrons now available, at much lower
voltages.
  * This work supported by the Department of Energy under contract
DE-AC03-76SF00515

</DOC>
<DOC>
<DOCNO> 178580 </DOCNO>
Pion Production Model - Connection between Dynamics and Quark Models


  We discuss the difficulties in testing the hadron models by using the N^*
parameters extracted from the empirical amplitude analyses of the pi-N and
gamma-N reaction data. As an alternative or perhaps a more advantageous
approach, we present a Hamiltonian formulation that can relate the pion
production dynamics and the constituent quark models of N^* structure. The
application of the approach in investigating the Delta and N^*(S_{11})
excitations is reviewed. It is found that while the Delta excitation can be
described satisfactory, the pi-N scattering in S_{11} channel can not be
described by the constituent quark models based on either the
one-gluon-exchange or one-meson-exchange mechanisms. A phenomenological
quark-quark potential has been constructed to reproduce the S_{11} amplitude.

</DOC>
<DOC>
<DOCNO> 174606 </DOCNO>
Cross sections for nuclide production in 1 GeV proton-irradiated 208-Pb


  114 cross sections for nuclide production in a 1.0 GeV proton-irradiated thin
208Pb target have been measured by the direct gamma spectrometry method using a
high-resolution Ge detector. The gamma spectra were processed by the GENIE-2000
code. The ITEP-developed SIGMA code was used together with the PCNUDAT nuclear
decay database to identify the gamma lines and to determine the cross sections.
The 27Al(p,x)22Na reaction was used to monitor the proton flux. Results of a
feasibility study of the auxiliary 27Al(p,x)24Na and 27Al(p,x)7Be monitor
reactions in the 0.07-2.6 GeV proton-energy range are presented as well. Most
of the experimental data have been analyzed by the LAHET (with ISABEL and
Bertini options), CEM95, CEM2k, INUCL, CASCADE, CASCADE/INPE, and YIELDX codes
that simulate hadron-nucleus interactions.

</DOC>
<DOC>
<DOCNO> 170309 </DOCNO>
Quantum authentication using entangled state


  A scheme of quantum authentication is presented. Two parties share
Einstein-Podolsky-Rosen (EPR) pairs previously as the authentication key which
servers as encoder and decoder. The authentication is accomplished with local
controlled-NOT operations and unitary rotations. It is shown that our scheme is
secure even in the presence of an eavesdropper who has complete control over
both classical and quantum channels. Another character of this protocol is that
the EPR sources are reusable. The robustness of this protocol is also
discussed.

</DOC>
<DOC>
<DOCNO> 71866 </DOCNO>
Multiplicity dependence of Bose-Einstein correlations in


  The observed pronounced multiplicity dependence of correlation functions in
hadron-hadron reactions and in particular of Bose-Einstein correlations
provides information about underlying physics. We discuss in this contribution
several interpretations, giving special attention to the string model for
Bose-Einstein correlations of Andersson and Hofmann, as well as the core-halo
picture of Csorgo, Lorstad and Zimanyi.

</DOC>
<DOC>
<DOCNO> 152381 </DOCNO>
Wess-Zumino Model in the Causal Approach


  The Wess-Zumino model is analysed in the framework of the causal approach of
Epstein-Glaser. The condition of invariance with respect to supersymmetry
transformations is similar to the gauge invariance in the Z\"urich formulation.
We prove that this invariance condition can be implemented in all orders of
perturbation theory, i.e. the anomalies are absent in all orders. This result
is of purely algebraic nature. We work consistently in the quantum framework
based on Bogoliubov axioms of perturbation theory so no Grassmann variables are
necessary.

</DOC>
<DOC>
<DOCNO> 8395 </DOCNO>
Robust half-metallicity and metamagnetism in Fe_{x}Co_{1-x}S_{2}


  The Fe_{x}Co_{1-x}S_{2} system is predicted, on the basis of density
functional calculations, to be a half metal for a large range of
concentrations. Unlike most known half metals, the half metallicity in this
system should be very stable with respect to crystallographic disorder and
other types of defects. The endmember of the series, CoS_{2}, is not a half
metal, but exhibits interesting and unusual magnetic properties which can,
however, be reasonably well understood within the density functional theory,
particularly with the help of the extended Stoner model. Calculations suggest
strong electron-phonon and electron-magnon coupling in the system, and probably
a bad metal behavior at high temperatures.

</DOC>
<DOC>
<DOCNO> 72193 </DOCNO>
Uncertainties on Atmospheric Neutrino Flux Calculations


  The strong evidence of new physics coming from atmospheric neutrino
experiments has motivated a series of critical studies to test the robustness
of the available flux calculations. In view of a more precise determination of
the parameters of new physics, new and more refined flux calculations are in
progress. Here we review the most important sources of theoretical
uncertainties which affect these computations, and the attempts currently under
way to improve them.

</DOC>
<DOC>
<DOCNO> 68338 </DOCNO>
A Comment on Self-Tuning and Vanishing Cosmological Constant in the


  In this note we elaborate on various five dimensional contributions to the
effective 4D cosmological constant in brane systems. In solutions with
vanishing 5D cosmological constant we describe a non-local mechanism of
cancellation of vacuum energy between the brane and the singularities. We
comment on a hidden fine tuning which is implied by this observation.

</DOC>
<DOC>
<DOCNO> 101991 </DOCNO>
Relations of multiple zeta values and their algebraic expression


  We establish a new class of relations among the multiple zeta values
\zeta(k_1,k_2,...,k_n), which we call the cyclic sum identities. These
identities have an elementary proof, and imply the "sum theorem" for multiple
zeta values. They also have a succinct statement in terms of "cyclic
derivations" as introduced by Rota, Sagan and Stein. In addition, we discuss
the expression of other relations of multiple zeta values via the shuffle and
"harmonic" products on the underlying vector space H of the noncommutative
polynomial ring Q<x,y>, and also using an action on Q<x,y> of the Hopf algebra
of quasi-symmetric functions.

</DOC>
<DOC>
<DOCNO> 118679 </DOCNO>
A Survey for Low-mass Stars and Brown Dwarfs in the Upper-Scorpius OB


  The Upper-Scorpius association is the OB association nearest to the Sun (145
pc). Its young age (5 Myr) makes it an ideal place to search for low-mass stars
and brown dwarfs, as these objects should be relatively bright. We have
performed a photometric search for the low-mass members of the association,
using the R, I, and Z filters. The completeness limit is I=18.5 and the
saturation limit is I=13. We obtain 138 candidate members, covering nearly the
entire M spectral type range. We find an excess of brown dwarf candidates over
the number predicted by a Miller-Scalo Initial Mass Function. In addition, we
have performed infrared imaging and low resolution optical spectroscopy of
selected candidates. We find that the infrared observations confirm the
spectral types obtained with the optical photometry. Furthermore, we find
H_alpha in emission in 20 of the 22 objects observed spectroscopically. As
H_alpha is an indicator of youth, we believe that these 20 objects may belong
to the association. One of them, UScoCTIO 128 has a very strong and constant
H_alpha line (equivalent width: -130 A), and its position in the color
magnitude diagram suggests that it is a brown dwarf with mass equal to 0.02
msun. Confirmation of this and the other candidates will have to wait for
higher resolution observations that can reveal spectroscopic mass indicators
like Li I and gravity indicators, such as K I and the subordinate lines of Na
I.

</DOC>
<DOC>
<DOCNO> 11297 </DOCNO>
Theory of the Half-Polarized Quantum Hall States


  We report a theoretical analysis of the half-polarized quantum Hall states
observed in a recent experiment. Our numerical results indicate that the ground
state energy of the quantum Hall $\nu= 2/3$ and $\nu= 2/5$ states versus spin
polarization has a downward cusp at half the maximal spin polarization. We map
the two-component fermion system onto a system of excitons and describe the
ground state as a liquid state of excitons with non-zero values of exciton
angular momentum.

</DOC>
<DOC>
<DOCNO> 118832 </DOCNO>
Error Estimates for Measurements of Cosmic Shear


  Weak lensing surveys will, in the near future, map the projected density of
the universe in an unbiased way. In a generalization of our earlier work, we
present estimators for useful statistics of the weak lensing convergence field,
the cumulants and cumulant correlators, and compute the variance associated
with these estimators. We also separate contributions from cosmic variance,
shot noise and intrinsic ellipticity of the source galaxies.

</DOC>
<DOC>
<DOCNO> 71794 </DOCNO>
Lepton number violating processes and Majorana neutrinos


  We discuss some generic properties of lepton number violating (\Lv) processes
and their relation to different entries of the Majorana neutrino mass matrix.
Present and near future experiments searching for these processes, except the
neutrinoless double beta decay, are unable to probe light(eV mass region) and
heavy(hundred GeV mass region) neutrinos. On the other hand due to the effect
of a resonant enhancement, some of \Lv decays can be very sensitive to the
intermediate mass neutrinos with typical masses in hundred MeV region. These
neutrinos may appear as admixtures of the three active and an arbitrary number
of sterile neutrino species. We analyze the experimental constraints on these
massive neutrino states and discuss their possible cosmological and
astrophysical implications.

</DOC>
<DOC>
<DOCNO> 101357 </DOCNO>
Rigidity of AMN vector spaces


  A metric vector space is asymptotically metrically normable (AMN) if there
exists a norm asymptotically isometric to the distance. We prove that AMN
vector spaces are rigid in the class of metric vector spaces under
asymptotically isometric perturbations. This result follows from a general
metric normability criterium.
 If the distance is translation invariant and satisfies an approximate
multiplicative condition then there exists a lipschitz equivalent norm.
Furthermore, we give necessary and sufficient conditions for the distance to be
asymptotically isometric to the norm.

</DOC>
<DOC>
<DOCNO> 100935 </DOCNO>
Two results on equations of nilpotent orbits


  We prove two results on the defining ideals of certain varieties of matrices.
Let us fix two positive integers r, e. Let M(r) be the set of r x r matrices
over a field K. We consider the closed subscheme of the nilpotent variety of
M(r) over K defined by the conditions char_A(T)=T^r, A^e=0. We prove that when
the characteristic of K is zero this scheme is reduced. Also for e=2 we prove
that this scheme is reduced over a field K of arbitrary characteristic.
  These results were motivated by the questions of G. Pappas and M. Rapoport
(compare their paper ''Local models in the ramified case I. The EL-case",
math.AG/0006222) and give answers to some of their conjectures.

</DOC>
<DOC>
<DOCNO> 7848 </DOCNO>
Phase separation in systems with charge ordering


  A simple model of charge ordering is considered. It is shown explicitly that
at any deviation from half-filling ($n \neq 1/2$) the system is unstable with
respect to phase separation into charge ordered regions with $n = 1/2$ and
metallic regions with smaller electron or hole density. Possible structure of
this phase-separated state (metallic droplets in a charge-ordered matrix)is
discussed. The model is extended to account for the strong Hund-rule onsite
coupling and the weaker intersite antiferromagnetic exchange. An analysis of
this extended model allows us to determine the magnetic structure of the
phase-separated state and to reveal the characteristic features of manganites
and other substances with charge ordering.

</DOC>
<DOC>
<DOCNO> 12464 </DOCNO>
Nanowire Gold Chains: Formation Mechanisms and Conductance


  Structural transformations, electronic spectra and ballistic transport in
pulled gold nanowires are investigated with ab initio simulations, and
correlated with recent measurements. Strain-induced yield of an initial
double-strand wire results first in formation of a bent-chain which transforms
upon further elongation to a linear atomic chain exhibiting dimerized atomic
configurations. These structures are stabilized by directional local bonding
with spd-hybridization. The conductance of the initial double-stranded contact
is close to 2g_0 and it drops sharply to 1g_0 during the transformation to a
single chain, exhibiting subsequently a 1g_0 plateau extending over an
elongation well above typical Au-Au distances.

</DOC>
<DOC>
<DOCNO> 72039 </DOCNO>
Coherent Exclusive Exponentiation for Precision Monte Carlo Calculations


  In this contribution we give a short overview of the new Coherent Exclusive
Exponentiation (CEEX) which is implemented in the new \KK MC event generator
for the process $e^+e^-\to f\bar{f} +n\gamma$, $f=\mu,\tau,d,u,s,c,b$ with
validity for center of mass energies from $\tau$ lepton threshold to 1TeV, that
is for LEP1, LEP2, SLC, future Linear Colliders, $b,c,\tau$-factories etc. In
CEEX effects due to photon emission from initial beams and outgoing fermions
are calculated in QED up to second-order, including all interference effects.
Electroweak corrections are included in first-order, at the amplitude level.
Beams can be polarized longitudinally and transversely, and all spin
correlations are incorporated in an exact manner. We describe briefly the
essence of CEEX as compared with older exclusive variants of the exponentiation
(EEX) and present samples of the numerical results, concentrating on the
question of the technical and physical precision for the total cross section
and for the charge asymmetry. New results on the interference between initial
and final state photon emission at LEP2 energies are also shown.

</DOC>
<DOC>
<DOCNO> 69086 </DOCNO>
A unitary model for structure functions and diffractive production at


  We propose a unified approach which describes both structure functions in the
small-$x$ region and diffractive production in $\gamma^*p$-interactions. It is
shown that the model, based on reggeon calculus and a quark-parton picture of
the interaction, gives a good description of available experimental data in a
broad region of $Q^2$ (including $Q^2 =0$) with a single Pomeron of intercept
$\alpha_P(0) = 1.2$. Predictions for very small $x$ are given and the problem
of saturation of parton densities is discussed.

</DOC>
<DOC>
<DOCNO> 178945 </DOCNO>
The inclusive reaction d(\gamma,\pi)NN in the first resonance region


  Inclusive single pion photoproduction on the deuteron is studied in the first
resonance region. The calculation is based on the use of the diagrammatic
approach. Pole diagrams and one-loop diagrams with NN rescattering in the final
state are taken into account. The elementary operator for pion photoproduction
from the nucleon is taken in on-shell form and calculated using the SAID and
MAID multipole analyses. Our predictions for total and differential cross
section show good agreement with the available experimental data. Invoking some
information on the reactions $gamma d\to\pi^0 d and $\gamma d\to np$ we predict
the total photoabsorption cross section for deuterium. We find that our results
overestimate the experimental data in the center of the \Delta-peak (\sim 320
MeV) by about 10%.

</DOC>
<DOC>
<DOCNO> 101755 </DOCNO>
Mathematical Basis for Physical Inference


  While the axiomatic introduction of a probability distribution over a space
is common, its use for making predictions, using physical theories and prior
knowledge, suffers from a lack of formalization. We propose to introduce, in
the space of all probability distributions, two operations, the OR and the AND
operation, that bring to the space the necessary structure for making
inferences on possible values of physical parameters. While physical theories
are often asumed to be analytical, we argue that consistent inference needs to
replace analytical theories by probability distributions over the parameter
space, and we propose a systematic way of obtaining such "theoretical
correlations", using the OR operation on the results of physical experiments.
Predicting the outcome of an experiment or solving "inverse problems" are then
examples of the use of the AND operation. This leads to a simple and complete
mathematical basis for general physical inference.

</DOC>
<DOC>
<DOCNO> 169891 </DOCNO>
A Lie algebraic approach to complex quasi exactly solvable potentials


  We use a Lie algebraic technique to construct complex quasi exactly solvable
potentials with real spectrum. In particular we obtain exact solutions of a
complex sextic oscillator potential and also a complex potential belonging to
the Morse family.

</DOC>
<DOC>
<DOCNO> 123096 </DOCNO>
AGN and starbursts at high redshift: High resolution EVN radio


  We present deep, wide-field European VLBI Network (EVN) 1.6 GHz observations
of the Hubble Deep Field (HDF) region with a resolution of 0.025 arcseconds.
Above the 210 microJy/beam (5sigma) detection level, the EVN clearly detects
two radio sources in a field that encompasses the HDF and part of the Hubble
Flanking Fields (HFF). The sources detected are: VLA J123644+621133 (a z=1.013,
low-luminosity FR-I radio source located within the HDF itself) and VLA
J123642+621331 (a dust enshrouded, optically faint, z=4.424 starburst system).
A third radio source, J123646+621404, is detected at the 4sigma level. The VLBI
detections of all three sources suggest that most of the radio emission of
these particular sources (including the dusty starburst) is generated by an
embedded AGN.

</DOC>
<DOC>
<DOCNO> 119676 </DOCNO>
Giant Molecular Outflows Powered by Protostars in L1448


  We present sensitive, large-scale maps of the CO J=1-0 emission of the L1448
dark cloud. These maps were acquired using the On-The-Fly capability of the
NRAO 12-meter telescope. CO outflow activity is seen in L1448 on parsec-scales
for the first time. Careful comparison of the spatial and velocity distribution
of our high-velocity CO maps with previously published optical and
near-infrared images and spectra has led to the identification of six distinct
CO outflows. We show the direct link between the heretofore unknown, giant,
highly-collimated, protostellar molecular outflows and their previously
discovered, distant optical manifestations. The outflows traced by our CO
mapping generally reach the projected cloud boundaries. Integrated intensity
maps over narrow velocity intervals indicate there is significant overlap of
blue- and red-shifted gas, suggesting the outflows are highly inclined with
respect to the line-of-sight, although the individual outflow position angles
are significantly different. The velocity channel maps also show that the
outflows dominate the CO line cores as well as the high-velocity wings. The
magnitude of the combined flow momenta, as well as the combined kinetic energy
of the flows, are sufficient to disperse the 50 solar mass NH3 cores in which
the protostars are currently forming, although some question remains as to the
exact processes involved in redirecting the directionality of the outflow
momenta to effect the complete dispersal of the parent cloud.

</DOC>
<DOC>
<DOCNO> 85364 </DOCNO>
An effective model of the spacetime foam


  An approximate model of the spacetime foam is offered in which each quantum
handle (wormhole) is a 5D wormhole-like solution. A spinor field is introduced
for an effective description of this foam. The topological handles of the
spacetime foam can be attached either to one space or connect two different
spaces. In the first case we have a wormhole with the quantum throat and such
object can demonstrate a model of preventing the formation the naked
singularity with relation $e > m$. In the second case the spacetime foam looks
as a dielectric with quantum handles as dipoles. It is supposed that
supergravity theories with a nonminimal interaction between spinor and
electromagnetic fields can be considered as an effective model approximately
describing the spacetime foam.

</DOC>
<DOC>
<DOCNO> 122235 </DOCNO>
Time-Resolved HST Spectroscopy of Four Eclipsing Magnetic Cataclysmic


  Time-resolved HST UV eclipse spectrophotometry is presented for the magnetic
CVs V1309 Ori, MN Hya, V2301 Oph, and V1432 Aql. Separation of the light curves
into wavebands allows the multiple emission components to be distinguished.
Photospheric hot spots are detected in V1309 Ori and V2301 Oph. The emission-
line spectra of V1309 Ori and MN Hya are unusual, with the strength of N V 1240
and N IV 1718 suggesting an overabundance of nitrogen. Three epochs of
observation of the asynchronous V1432 Aql cover ~1/3 of a 50-day lap cycle
between the white dwarf spin and binary orbit. The light curves vary from epoch
to epoch and as a function of waveband. The dereddened UV spectrum is extremely
bright and the spectral energy distribution coupled with the duration of
eclipse ingress indicate that the dominant source of energy is a hot
(T~35,000K) white dwarf. Undiminished line emission through eclipse indicates
that the eclipse is caused by the accretion stream, not the secondary star. The
hot white dwarf, combined with its current asynchronous nature and rapid
timescale for relocking, suggests that V1432 Aql underwent a nova eruption in
the past 75-150 yr. The reversed sense of asynchronism, with the primary star
currently spinning up toward synchronism, is not necessarily at odds with this
scenario, if the rotation of the magnetic white dwarf can couple to the ejecta
during the wind phase of the eruption.

</DOC>
<DOC>
<DOCNO> 118701 </DOCNO>
Large-Scale Cosmic Shear Measurements


  We present estimates of the gravitational lensing shear variance obtained
from images taken at the CFHT using the UH8K CCD mosaic camera. Six fields were
observed for a total of 1 hour each in V and I, resulting in catalogs
containing approximately 20,000$ galaxies per field, with properly calibrated
and optimally weighted shear estimates. These were averaged in cells of sizes
ranging from 1'.875 to 30' to obtain estimates of the cosmic shear variance
$<\bar{\gamma}^2>$, with uncertainty estimated from the scatter among the
estimates for the 6 fields. Our most reliable estimator for cosmic shear is
provided by the cross-correlation of the shear measured in the two passbands.
At scales $\lsim 10'$ the results are in good agreement with those of van
Waerbeke et al. 2000, Bacon et al. 2000 and Wittman et al. 2000 and with
currently fashionable cosmological models. At larger scales the shear variance
falls below the theoretical predictions, and on the largest scales we find a
null detection of shear variance averaged in 30' cells of $<\bar{\gamma}^2 > =
(0.28 \pm 1.84) \times 10^{-5}$.

</DOC>
<DOC>
<DOCNO> 118928 </DOCNO>
Unavoidable Selection Effects in the Analysis of Faint Galaxies in the


  (Abridged) We present a detailed analysis of the number count and photometric
redshift distribution of faint galaxies in the Hubble Deep Field (HDF), paying
a special attention to the selection effects including the cosmological dimming
of surface brightness of galaxies. We find a considerably different result from
previous studies ignoring the selection effects, and these effects should
therefore be taken into account in the analysis. We find that the model of pure
luminosity evolution (PLE) of galaxies in the Einstein-de Sitter (EdS) universe
predicts much smaller counts than those observed at faint magnitude limits by a
factor of more than 10, so that a very strong number evolution of galaxies with
\eta > 3-4 must be invoked to reproduce the I_{814} counts, when parametrized
as \phi^* \propto (1+z)^\eta. However we show that such a strong number
evolution under realistic merging processes of galaxies can not explain the
steep slope of the B_{450} and V_{606} counts, and it is seriously inconsistent
with their photometric redshift distribution. We find that these difficulties
still persist in an open universe with \Omega_0 > 0.2, but are resolved only
when we invoke a $\Lambda$-dominated flat universe, after examining various
systematic uncertainties in modeling the formation and evolution of galaxies.
The present analysis revitalizes the practice of using faint number counts as
an important cosmological test, giving one of the arguments against the EdS
universe and suggests acceleration of the cosmic expansion by vacuum energy
density. While a modest number evolution of galaxies with \eta ~ 1 is still
necessary even in a Lambda-dominated universe, a stronger number evolution with
\eta > 1 is rejected from the HDF data, giving a strong constraint on the
merger history of galaxies.

</DOC>
<DOC>
<DOCNO> 122282 </DOCNO>
Numerical simulations of the accretion-ejection instability


  The Accretion-Ejection Instability (AEI) is explored numerically using a
global 2d model of the inner region of a magnetised accretion disk. The disk is
initially currentless but threaded by an external vertical magnetic field
created by external currents, and frozen in the flow. In agreement with the
theory a spiral instability, similar in many ways to those observed in
self-gravitating disks, but driven by magnetic stresses, develops when the
magnetic field is close to equipartition with the disk thermal pressure. The
present non-linear simulations give good evidence that such an instability can
occur in the inner region of accretion disks.

</DOC>
<DOC>
<DOCNO> 117051 </DOCNO>
Test of Cosmic Spatial Isotropy for Polarized Electrons Using a


  To test the cosmic spatial isotropy, we use a rotatable torsion balance
carrying a transversely spin-polarized ferrimagnetic Dy_{6}Fe_{23} mass. With a
rotation period of one hour, the period of anisotropy signal is reduced from
one sidereal day by about 24 times, and hence the 1/f noise is greatly reduced.
Our present experimental results constrain the cosmic anisotropy Hamiltonian H
= C_{1} sigma_{1} + C_{2} sigma_{2} + C_{3} sigma_{3} (sigma_{3} is in the axis
of earth rotation) to (C_{1}^{2} +C_{2}^{2})^{1/2} = (1.8 +- 5.3) X 10^{-21} eV
and | C_{3} | = (1.2 +- 3.5) X 10^{-19} eV. This improves the previous limits
on (C_{1},C_{2}) by 120 times and C_{3} by a factor of 800.

</DOC>
<DOC>
<DOCNO> 102739 </DOCNO>
On the solutions of weak normality equations in multidimensional case


  The system of weak normality equations constitutes a part in the complete
system of normality equations. Solutions of each of these two systems of
equations are associated with some definite classes of Newtonian dynamical
systems in Riemannian manifolds. In this paper for the case of simplest flat
Riemannian manifold $M=\Bbb R^n$ with $n\geq 3$ we show that there exist
solutions of weak normality equations that do not solve complete system of
normality equations in whole. Hence associated classes of Newtonian dynamical
systems do not coincide with each other.

</DOC>
<DOC>
<DOCNO> 102303 </DOCNO>
A h-principle for open relations invariant under foliated isotopies


  This paper presents a natural extension to foliated spaces of the following
result due to Gromov : the h-principle for open, invariant differential
relations is valid on open manifolds. The definition of openness for foliated
spaces adopted here involves a certain type of Morse functions. Consequences
concerning the problem of existence of regular Poisson structures, the original
motivation for this work, are presented.

</DOC>
<DOC>
<DOCNO> 102094 </DOCNO>
Knots, links and branes at large N


  We consider Wilson loop observables for Chern-Simons theory at large N and
its topological string dual and extend the previous checks for this duality to
the case of links. We find an interesting structure involving
representation/spin degeneracy of branes ending on branes which features in the
large N dual description of Chern-Simons theory. This leads to a refinement of
the integer invariants for links and knots. We illustrate our results with
explicit computations on the Chern-Simons side.

</DOC>
<DOC>
<DOCNO> 119246 </DOCNO>
Hard X-ray Observation of Abell 496


  We report the results of hard X-ray observations of Abell 496 (A496), a
nearby relaxed cluster, using the Rossi X-ray Timing Explorer (RXTE). The 3-20
keV spectrum of this cluster is well-modeled by a thermal component of kT ~ 4.1
keV plus a cooling flow with mass accretion rate of \dot{M} ~ 285 M_{\odot}
yr^{-1}. The spectrum is equally well-modeled by a multi-temperature plasma
component with a Gaussian temperature distribution of mean temperature 3.8 keV
and \sigma_{kT} ~ 0.9 keV. The metallicity is found to be approximately 1/3
solar; however, the Ni/Fe ratio is about 3.6. No significant nonthermal
emission at hard X-rays was detected for this cluster. We discuss the
implications of the models presented here and compare them with the temperature
profiles derived for this cluster using the Advanced Satellite for Cosmology
and Astrophysics (ASCA). Our results are inconsistent with declining
temperature profiles.

</DOC>
<DOC>
<DOCNO> 119971 </DOCNO>
ASCA Observation of the Lyman-limit Quasar PKS2145+067


  X-ray observation of a famous Lyman-limit quasar PKS2145+067at z_em= 0.990
was carried with ASCA. The source showed a 2-10 keV flux of 1.3 E-11 erg cm^-2
sec^-1 (L_X = 2.5 E46 erg sec^-1 for H_0=50 km s^-1 Mpc^-1) described by a
power-law spectrum with a photon index Gamma=1.63 +/- 0.04 . In the ASCA energy
band, no excess absorption was detected implying the absorption column density
at z_ ab=0.791 was less than 1.6 E21 cm^-2 if absorbing medium had a metal
abundance of 0.5 solar. Comparison with previous Einstein and ROSAT
observations shows that PKS2145+067 has increased its luminosity by a factor of
2--3 between 1991 and 1998.

</DOC>
<DOC>
<DOCNO> 99633 </DOCNO>
Global existence and scattering for the nonlinear Schrodinger equation


  We consider the NLS on Schwarzschild manifold.For radial solutions with
sufficiently localized initial data,global existence,L^p estimates and
asymptotic completeness of the wave operators is proved

</DOC>
<DOC>
<DOCNO> 100794 </DOCNO>
On the mean value of the energy for resonant states


  In this work we discuss possible definitions of the mean value of the energy
for a resonant (Gamow) state. The mathematical and physical aspects of the
formalism are reviewed. The concept of rigged Hilbert space is used as a
supportive tool in dealing with Gamow-resonances.

</DOC>
<DOC>
<DOCNO> 121789 </DOCNO>
Circumbinary disks and cataclysmic variable evolution


  The influence of a circumbinary (CB) disk on the evolution of cataclysmic
variable (CV) binary systems is investigated. We show that CB mass surface
densities sufficient to influence the evolution rate are plausibly provided by
the outflows observed in CVs, if the net effect of these winds is to deliver
$10^{-4}$--$10^{-3}$ of the mass transfer rate to the CB disk. The torque
exerted by the CB disk provides a positive feedback between mass transfer rate
and CB disk mass which can lead to mass transfer rates of $\sim 10^{-8}
-10^{-7} \mpy$. This mechanism may be responsible for causing the range of
variation of mass transfer rates in CV's. In particular, it may explain rates
inferred for the novalike variables and the supersoft X-ray binary systems
observed near the upper edge of the period gap ($P \sim 3 - 4$ hr), as well as
the spread in mass transfer rates above and below the period gap. Consquences
and the possible observability of such disks are discussed.

</DOC>
<DOC>
<DOCNO> 8010 </DOCNO>
Temporal correlations and neural spike train entropy


  Sampling considerations limit the experimental conditions under which
information theoretic analyses of neurophysiological data yield reliable
results. We develop a procedure for computing the full temporal entropy and
information of ensembles of neural spike trains, which performs reliably for
limited samples of data. This approach also yields insight upon the role of
correlations between spikes in temporal coding mechanisms. The method, when
applied to recordings from complex cells of the monkey primary visual cortex,
results in lower RMS error information estimates in comparison to a `brute
force' approach.

</DOC>
<DOC>
<DOCNO> 101095 </DOCNO>
Projective dimension is a lattice invariant


  We show that, for a free abelian group $G$ and prime power $p^\nu$, every
direct sum decomposition of the group $G/p^\nu G$ lifts to a direct sum
decomposition of $G$. This is the key result we use to show that, if $R$ is a
commutative von Neumann regular ring, and $\mathcal{E}$ a set of idempotents in
$R$, then the projective dimension of the ideal $\mathcal{E} R$ as an
$R$-module is the same as the projective dimension of the ideal $\mathcal{EB}$,
where $\mathcal{B}$ is the boolean algebra generated by $\mathcal{E} \cup
\{1\}$. This answers a thirty year old open question of R. Wiegand. The proof
is based on gaussian elimination on an $\omega \times \omega$ matrix, with
adaptations enabling one to pass from the integers modulo $p^\nu$ to the
integers.

</DOC>
<DOC>
<DOCNO> 121200 </DOCNO>
First Stellar Abundances in NGC 6822 from VLT-UVES and Keck-HIRES


  We have obtained the first high resolution spectra of individual stars in the
dwarf irregular galaxy, NGC 6822. The spectra of the two A-type supergiants
were obtained at the VLT and Keck Observatories, using UVES and HIRES,
respectively. A detailed model atmospheres analysis has been used to determine
their atmospheric parameters and elemental abundances. The mean iron abundance
from these two stars is $<$[Fe/H]$>=-$0.49 $\pm$0.22 ({\it $\pm$0.21}, with Cr
yielding a similar underabundance, $<$[Cr/H]$>=-$0.50 $\pm$0.20 ({\it
$\pm$0.16}). This confirms that NGC 6822 has a metallicity that is slightly
higher than that of the SMC, and is the first determination of the present-day
iron-group abundances in NGC 6822. The mean stellar oxygen abundance,
12+log(O/H)=8.36 $\pm$0.19 ({\it $\pm$0.21}),is in good agreement with the
nebular oxygen results. Oxygen has the same underabundance as iron,
$<$[O/Fe]$>$=+0.02 $\pm$0.20 ({\it $\pm$0.21}). This O/Fe ratio is very similar
to that seen in the Magellanic Clouds, which supports the picture that chemical
evolution occurs more slowly in these lower mass galaxies, although the O/Fe
ratio is also consistent with that observed in comparatively metal-poor stars
in the Galactic disk. Combining all of the available abundance observations for
NGC 6822 shows that there is no trend in abundance with galactocentric
distance. However, a subset of the highest quality data are consistent with a
radial abundance gradient.

</DOC>
<DOC>
<DOCNO> 9828 </DOCNO>
Persistent current in metals with a large dephasing rate


  In a weakly disordered metal electron interactions are responsible for both
decoherence of the quasi-particles as well as for quantum corrections to
thermodynamic properties. We consider electrons which are interacting with
two-level-systems. We show that the two-level-systems enhance the average
equilibrium (``persistent'') current in an ensemble of mesoscopic rings. The
result supports the recent suggestion that two puzzles in mesoscopic physics
may be related: The low temperature saturation of the dephasing time and the
high persistent current in rings.

</DOC>
<DOC>
<DOCNO> 84473 </DOCNO>
Black Hole Scan


  Gravitation theories selected by requiring that they have a unique anti-de
Sitter vacuum with a fixed cosmological constant are studied. For a given
dimension d, the Lagrangians under consideration are labeled by an integer
k=1,2,...,[(d-1)/2]. Black holes for each d and k are found and are used to
rank these theories. A minimum possible size for a localized electrically
charged source is predicted in the whole set of theories, except General
Relativity. It is found that the thermodynamic behavior falls into two classes:
If d-2k=1, these solutions resemble the three dimensional black hole,
otherwise, their behavior is similar to the Schwarzschild-AdS_4 geometry.

</DOC>
<DOC>
<DOCNO> 178695 </DOCNO>
$\Upsilon$ absorption in hadronic matter


  The cross sections of $\Upsilon$ absorption by $\pi$ and $\rho$ mesons are
evaluated in a meson-exchange model. Including form factors with a cutoff
parameter of 1 or 2 GeV, we find that due to the large threshold of these
reactions the thermal average of their cross sections is only about 0.2 mb at a
temperature of 150 MeV. Our results thus suggest that the absorption of
directly produced $\Upsilon$ by hadronic comovers in high energy heavy ion
collisions is unimportant.

</DOC>
<DOC>
<DOCNO> 67971 </DOCNO>
Statistics of clustering of ultra-high energy cosmic rays and the number


  Observation of clustering of ultra-high energy cosmic rays (UHECR) suggests
that they are emitted by compact sources. Assuming small deflection of UHECR
during the propagation, the statistical analysis of clustering allows to
estimate the spatial density of the sources, h, including those which have not
yet been observed directly. When applied to astrophysical models involving
extra-galactic sources, the estimate based on 14 events with energy E>10^{20}
eV gives h ~ 6 X 10^{-3} Mps^{-3}. With increasing statistics, this estimate
may lead to exclusion of the models which associate the production of UHECR
with exceptional galaxies such as AGN, powerful radio-galaxies, dead quasars,
and models based on gamma ray bursts.

</DOC>
<DOC>
<DOCNO> 69314 </DOCNO>
Single Pion Production in Neutrino Reactions and Estimates for


  We calculate single pion production by neutrinos in the resonance region. We
consider both charged and neutral current reactions on free protons and
neutrons. We present differential and total cross sections which can be
compared with experiments. Then we use these results to calculate the spectra
of the emerging pions including the Pauli suppression factor and rescattering
corrections for reactions in heavy nuclei. Our results will be useful for
studying single pion production and for investigating neutrino oscillations in
future experiments.

</DOC>
<DOC>
<DOCNO> 122335 </DOCNO>
The violent environment of the Shapley Concentration: a multiwavelength


  Rich superclusters are the ideal environment for the detection of cluster
mergings, because the high peculiar velocities induced by the enhanced local
density of the large-scale structure favour the cluster-cluster collisions, in
the same way as seen in the simulations.
 The Shapley Concentration supercluster represents a unique laboratory where it
is possible to follow cluster mergings and to test related astrophysical
consequences, as the formation of shocks, radio halos, relics and wide angle
tail radiosources, and the presence of galaxies with enhanced star formation.
 We present the results of an extensive multiwavelength survey of the central
part of the Shapley Concentration, with the use of optical spectra, radio and
X-ray data.

</DOC>
<DOC>
<DOCNO> 100213 </DOCNO>
Duality and modular class of a Nambu-Poisson structure


  In this paper we introduce cohomology and homology theories for Nambu-Poisson
manifolds. Also we study the relation between the existence of a duality for
these theories and the vanishing of a particular Nambu-Poisson cohomology
class, the modular class. The case of a regular Nambu-Poisson structure and
some singular examples are discussed.

</DOC>
<DOC>
<DOCNO> 9601 </DOCNO>
Thermodynamics of Bose-Condensed Atomic Hydrogen


  We study the thermodynamics of the Bose-condensed atomic hydrogen confined in
the Ioffe-Pritchard potential. Such a trapping potential, that models the
magnetic trap used in recent experiments with hydrogen, is anharmonic and
strongly anisotropic. We calculate the ground-state properties, the condensed
and non-condensed fraction and the Bose-Einstein transition temperature. The
thermodynamics of the system is strongly affected by the anharmonicity of this
external trap. Finally, we consider the possibility to detect Josephson-like
currents by creating a double-well barrier with a laser beam.

</DOC>
<DOC>
<DOCNO> 152481 </DOCNO>
The BRS invariance of noncommutative U(N) Yang-Mills theory at the


  We show that U(N) Yang-Mills theory on noncommutative Minkowski space-time
can be renormalized, in a BRS invariant way, at the one-loop level, by
multiplicative dimensional renormalization of its coupling constant, its gauge
parameter and its fields. It is shown that the Slavnov-Taylor equation, the
gauge-fixing equation and the ghost equation hold, up to order $\hbar$, for the
MS renormalized noncommutative U(N) Yang-Mills theory. We give the value of the
pole part of every 1PI diagram which is UV divergent.

</DOC>
<DOC>
<DOCNO> 83486 </DOCNO>
Scaling Up Inductive Logic Programming by Learning from Interpretations


  When comparing inductive logic programming (ILP) and attribute-value learning
techniques, there is a trade-off between expressive power and efficiency.
Inductive logic programming techniques are typically more expressive but also
less efficient. Therefore, the data sets handled by current inductive logic
programming systems are small according to general standards within the data
mining community. The main source of inefficiency lies in the assumption that
several examples may be related to each other, so they cannot be handled
independently.
  Within the learning from interpretations framework for inductive logic
programming this assumption is unnecessary, which allows to scale up existing
ILP algorithms. In this paper we explain this learning setting in the context
of relational databases. We relate the setting to propositional data mining and
to the classical ILP setting, and show that learning from interpretations
corresponds to learning from multiple relations and thus extends the
expressiveness of propositional learning, while maintaining its efficiency to a
large extent (which is not the case in the classical ILP setting).
  As a case study, we present two alternative implementations of the ILP system
Tilde (Top-down Induction of Logical DEcision trees): Tilde-classic, which
loads all data in main memory, and Tilde-LDS, which loads the examples one by
one. We experimentally compare the implementations, showing Tilde-LDS can
handle large data sets (in the order of 100,000 examples or 100 MB) and indeed
scales up linearly in the number of examples.

</DOC>
<DOC>
<DOCNO> 8258 </DOCNO>
Critical neutron scattering study of the compositional phase transition


  Cu1-xMgxGeO3 undergoes a first-order phase transition at a critical
concentration xc between an antiferromagnetic (AF) state on dimerized lattice
(D-AF) and an AF Neel state on undistorted uniform lattice (U-AF). Previous
magnetic susceptibility measurements showed xc = 0.023 while a recent neutron
scattering study reported xc = 0.027 +- 0.001. The present critical scattering
due to antiferromagnetic fluctuations near the superlattice reflection
(0,1,1/2) unambiguously determines xc = 0.028 +- 0.001 at TN = 3.4 ~ 4 K. Also
at T = 1.3 K, the phase boundary was determined as xc = 0.028 +- 0.001 by
observation of a jump of an effective magnetic moment across xc.

</DOC>
<DOC>
<DOCNO> 68890 </DOCNO>
Flat direction condensate instabilities in the MSSM


  Coherently oscillating scalar condensates formed along flat directions of the
MSSM scalar potential are unstable with respect to spatial perturbations if the
potential is flatter than phi^2, resulting in the formation of non-topological
solitons such as Q-balls. Using renormalization group we calculate the
corrections to the phi^2 potential for a range of flat directions and show that
unstable condensates are a generic feature of the MSSM. Exceptions arise for an
experimentally testable range of stop and gluino masses when there are large
admixtures of stops in the flat direction scalar.

</DOC>
<DOC>
<DOCNO> 170035 </DOCNO>
Laser Induced Condensation of Bosonic Gases in Traps


  We consider collective laser cooling of atomic gas in the Festina lente
regime, when the heating effects associated with photon reabsorptions are
suppressed. We demonstrate that an appropriate sequence of laser pulses allows
to condense a gas of trapped bosonic atoms into the ground level of the trap in
the presence of collisions. Such condensation is robust and can be achieved in
experimentally feasible traps. We extend significantly the validity of our
previous numerical studies, and present new analytic results concerning
condensation in the limit of rapid thermalization. We discuss in detail
necessary conditions to realize all optical condensate in weak condensation
regime and beyond.

</DOC>
<DOC>
<DOCNO> 68722 </DOCNO>
Next-to-leading order QCD corrections to top quark spin correlations at


  Future hadron collider experiments are expected to record large to huge
samples of $t\bar t$ events. The analysis of these data with respect to $t\bar
t$ spin-spin correlations requires precise predictions of the production of
these quark pairs in a general spin configuration. Therefore we have computed,
at next-to-leading order (NLO) in the QCD coupling, the spin density matrices
describing $t\bar t$ production by quark antiquark annihilation, which is the
dominant production process at the Tevatron. Moreover we have computed the
strength of the $t\bar t$ spin correlation at NLO, using various spin
quantization axes.

</DOC>
<DOC>
<DOCNO> 84492 </DOCNO>
Extra Force in Brane Worlds


  By carefully analyzing the geodesic motion of a test particle in the bulk of
brane worlds, we identify an extra force which is recognized in spacetime of
one lower dimensions as a non-gravitational force acting on the particle. Such
extra force acts on the particle in such a way that the conventional particle
mechanics in one lower dimensions is violated, thereby hinting at the
higher-dimensional origin of embedded spacetime in the brane world scenario. We
obtain the explicit equations describing the motion of the bulk test particle
as observed in one lower dimensions for general gravitating configurations in
brane worlds and identify the extra non-gravitational force acting on the
particle measured in one lower dimensions.

</DOC>
<DOC>
<DOCNO> 150630 </DOCNO>
Infra-red dynamics of D1-branes at the conifold


  We study the infra-red dynamics of D1-branes at the conifold. We show using
methods developed to study the infra-red dynamics of (4,4) theories, the
infra-red degrees of freedom of the (2,2) theory of a single D1-brane at the
conifold is that of a linear dilaton with background charge of $\sqrt{2}$ and a
compact scalar. The gauge theory of $N$ D1-branes at the conifold is used to
formulate the matrix string in the conifold background.

</DOC>
<DOC>
<DOCNO> 101628 </DOCNO>
Basic Properties of Coherent and Generalized Coherent Operators


  In this letter we make a brief review of some basic properties (the matrix
elements, the trace, the Glauber formula) of coherent operators and study the
corresponding ones for generalized coherent operators based on Lie algebra
su(1,1). We also propose some problems.

</DOC>
<DOC>
<DOCNO> 12403 </DOCNO>
Infiltration through porous media


  We study the kinetics of infiltration in which contaminant particles, which
are suspended in a flowing carrier fluid, penetrate a porous medium. The
progress of the ``invader'' particles is impeded by their trapping on active
``defender'' sites which are on the surfaces of the medium. As the defenders
are used up, the invader penetrates further and ultimately breaks through. We
study this process in the regime where the particles are much smaller than the
pores so that the permeability change due to trapping is negligible. We develop
a family of microscopic models of increasing realism to determine the
propagation velocity of the invasion front, as well as the shapes of the
invader and defender profiles. The predictions of our model agree qualitatively
with experimental results on breakthrough times and the time dependence of the
invader concentration at the output. Our results also provide practical
guidelines for improving the design of deep bed filters in which infiltration
is the primary separation mechanism.

</DOC>
<DOC>
<DOCNO> 13188 </DOCNO>
Fluctuations in the presence of fields -Phenomenological Gaussian


  The work approaches the study of the fluctuations for the thermodynamic
systems in the presence of the fields. The approach is of phenomenological
nature and developed in a Gaussian approximation. The study is exemplified on
the cases of a magnetizable continuum in a magnetoquasistatic field, as well as
for the so called discrete systems. In the last case one finds that the
fluctuations estimators depends both on the intrinsic properties of the system
and on the characteristics of the environment. Following some earlier ideas of
one of the authors we present a new class of thermodynamic inequalities for the
systems investigated in this paper. In the case of two variables the mentioned
inequalities are nothing but non-quantum analogues of the well known quantum
Heisenberg (''uncertainty'') relations. Also the obtained fluctuations
estimators support the idea that the Boltzmann's constant k has the
signification of a generic indicator of stochasticity for thermodynamic
systems.
  Pacs number(s): 05.20.-y, 05.40.-a, 05.70.-a, 41.20.Gz

</DOC>
<DOC>
<DOCNO> 71061 </DOCNO>
The Coulomb Phase Revisited


  Motivated by the forthcoming data from the E950 experiment at BNL for small
angle polarized proton-carbon scattering we revisit the problem of Coulomb
phase. The approximation usually used with the momentum transfer squared (q^2)
small compared to the inverse elastic slope is not justified within the
kinematics of the E950 experiment. We go beyond this approximation and derive a
new rather simple expression which recovers the formula of Bethe at small q^2,
but is valid at any momentum transfer.

</DOC>
<DOC>
<DOCNO> 11383 </DOCNO>
Reentrant spin glass behavior in a layered manganite La1.2Sr1.8Mn2O7


  We report here a detailed study of AC/DC magnetization and
longitudinal/transverse transport properties of
La$_{1.2}$Sr$_{1.8}$Mn$_{2}$O$_{7}$ single crystals below $T_{c}$ = 121 K. We
find that the resistivity upturn below 40 K is related to the reentrant spin
glass phase at the same temperature, accompanied by additional anomalous Hall
effects. The carrier concentration from the ordinary Hall effects remains
constant during the transition and is close to the nominal doping level (0.4
holes/Mn). The spin glass behavior comes from the competition between
ferromagnetic double exchange and antiferromagnetic superexchange interactions,
which leads to phase separation, i.e. a mixture of ferromagnetic and
antiferromagnetic clusters, representing the canted antiferromagnetic state.

</DOC>
<DOC>
<DOCNO> 120245 </DOCNO>
Mass Loss from Globular Clusters


  We consider both observational and theoretical issues related to dynamical
mass loss from the old globular star clusters of the Galaxy. On the
observational side the evidence includes tidal tails and extratidal extensions,
kinematic effects, effects on the mass function, and influences on the
statistical properties of surviving objects. Even for isolated clusters, the
theoretical issues are not fully understood. The effects of a steady tide (i.e.
for a cluster in a circular orbit) include the imposition of a tidal boundary,
and lowering of the escape energy. Less familiar, however, are the effects of
induced mass loss. Even the definition of an ``escaper'' is not
straightforward. When mass loss is driven by relaxation, as in N-body models,
the rate of loss of mass does not scale in a simple way with the relaxation
time. Reasons for this include the very long time scales on which stars escape
even with energies above the escape threshold. For the realistic case of
unsteady tides it is still unclear under what circumstances mass loss is
dominated by relaxation or tidal heating.

</DOC>
<DOC>
<DOCNO> 85276 </DOCNO>
Energy Distribution of a Schwarzschild Black Hole in a Magnetic Universe


  We obtain the energy distribution of a Schwarzschild black hole in a magnetic
universe in the Tolman prescription.

</DOC>
<DOC>
<DOCNO> 169818 </DOCNO>
Coherent Control of Magneto-optical Rotation


  The paper has been withdrawn by authors.

</DOC>
<DOC>
<DOCNO> 116807 </DOCNO>
A Fast Switchyard for the TESLA FEL-Beam Using a Superconducting


  In the present design of the TESLA Linear Collider with integrated X-ray
Laser Facility it is necessary that 1 ms long bunch trains with about 10000
bunches are generated and distributed to several free electron laser (FEL) beam
lines. The different scientific applications of the X-ray FELs need specific
filling patterns of the bunches in the bunch train. It is shown that a fast
switch-yard based on a superconducting transverse mode cavity can be used to
generate the required bunch pattern in a flexible way while keeping the beam
loading in the main linear accelerator constant. The conceptual design of the
beam optics and the transverse mode cavity are presented.

</DOC>
<DOC>
<DOCNO> 152638 </DOCNO>
String Field Theory Around the Tachyon Vacuum


  Assuming that around the tachyon vacuum the kinetic term of cubic open string
field theory is made purely of ghost operators we are led to gauge invariant
actions which manifestly implement the absence of open string dynamics around
this vacuum. We test this proposal by showing the existence of lump solutions
of arbitrary codimension in this string field theory. The key ingredients in
this analysis are certain assumptions about the analyticity properties of
tachyon Green's functions. With the help of some further assumptions about the
properties of these Green's functions, we also calculate the ratios of tensions
of lump solutions of different dimensions. The result is in perfect agreement
with the known answers for the ratios of tensions of D-branes of different
dimensions.

</DOC>
<DOC>
<DOCNO> 150587 </DOCNO>
Logarithmic Conformal Field Theories Near a Boundary


  We consider logarithmic conformal field theories near a boundary and derive
the general form of one and two point functions. We obtain results for
arbitrary and two dimensions. Application to two dimensional
magnetohydrodynamics is discussed.

</DOC>
<DOC>
<DOCNO> 152566 </DOCNO>
D-brane Dynamics and the Quantum Hall Effect


  We study the recently proposed D-brane configuration [hep-th/0010105]
modeling the quantum Hall effect, focusing on the nature of the interactions
between the charged particles. Our analysis indicates that the interaction is
repulsive, which it should be for the ground state of the system to behave as a
quantum Hall liquid. The strength of interactions varies inversely with the
filling fraction, leading us to conclude that a Wigner crystal is the ground
state at small nu. For larger rational nu (still less than unity), it is
reasonable to expect a fractional quantum Hall ground state.

</DOC>
<DOC>
<DOCNO> 10541 </DOCNO>
Statistical Analysis of Genealogical Trees for Polygamic Species


  Repetitions within a given genealogical tree provides some information about
the degree of consanguineity of a population. They can be analyzed with
techniques usually employed in statistical physics when dealing with fixed
point transformations. In particular we show that the tree features strongly
depend on the fractions of males and females in the population, and also on the
offspring probability distribution. We check different possibilities, some of
them relevant to human groups, and compare them with simulations.

</DOC>
<DOC>
<DOCNO> 72293 </DOCNO>
Axion Radiation from Strings


  This paper revisits the problem of the string decay contribution to the axion
cosmological energy density. We show that this contribution is proportional to
the average relative increase when axion strings decay of a certain quantity
$N_{\rm ax}$ which we define. We carry out numerical simulations of the
evolution and decay of circular and non-circular string loops, of bent strings
with ends held fixed, and of vortex-antivortex pairs in two dimensions. In the
case of string loops and of vortex-antivortex pairs, $N_{\rm ax}$ decreases by
approximately 20%. In the case of bent strings, $N_{\rm ax}$ remains constant
or increases slightly. Our results imply that the string decay contribution to
the axion energy density is of the same order of magnitude as the
well-understood contribution from vacuum realignment.

</DOC>
<DOC>
<DOCNO> 11404 </DOCNO>
Motional narrowing effect in certain random binary lattices


  We present a model for a class of random binary lattices by introducing a
one-dimensional system where impurities are placed in one sublattice while host
atoms lie on the other sublattice. The source of disorder is the stochastic
fluctuation of the impurity energy from site to site. We study the optical
absorption spectra and the peculiarities of the motional narrowing effect at
the band edges for perturbative and nonperturbative degrees of disorder.
Analytical results agree well with numerical simulations.

</DOC>
<DOC>
<DOCNO> 8244 </DOCNO>
Breakdown of time-dependent mean-field theory for a one-dimensional


  We show that the time-dependent nonlinear Schrodinger equation of mean-field
theory has limited utility for a one-dimensional condensate of impenetrable
bosons. Mean-field theory with its associated order parameter predicts
interference between split condensates that are recombined, whereas an exact
many-body treatment shows minimal interference.

</DOC>
<DOC>
<DOCNO> 68539 </DOCNO>
Scattering of a particle with spin by atomic chain as null test of


  T-odd P-even long-range electromagnetic interaction of a particle of spin 1/2
with the nucleus is considered. Though matrix element of the interaction is
zero for the particles on mass shell, nevertheless, null test exists for the
interaction. The test consists in measuring of the spin-dependent T-odd P-even
forward elastic scattering amplitude of a particle of spin 1/2 by atomic chain
(axis) in a crystall.

</DOC>
<DOC>
<DOCNO> 11194 </DOCNO>
Self-consistent theory of the thermal softening and instability of


  We consider the thermal softening of crystals due to anharmonicity.
Self-consistent methods find a maximum temperature for a stable crystal, which
gives an upper bound to the melting temperature. Previous workers have shown
that the self-consistent harmonic approximation (SCHA) gives misleading results
for the thermal stability of crystals. The reason is that the most important
diagrams in the perturbation expansion around harmonic theory are not included
in the SCHA. An alternative approach is to solve a self-consistent Dyson
equation (SCA) for a selection of diagrams, the simplest being a (3+4)-SCA.
However, this gives an unsatisfactory comparison to numerical results on the
thermal and quantum melting of two-dimensional (2D) Coulomb-interacting
particles (equivalent to vortex-lattice melting in two and three dimensions).
We derive an improved self-consistent method, the two-vertex-SCHA, which gives
much better agreement to the simulations. Our method allows for accurate
calculation of the thermal softening of the shear modulus for 2D crystals and
for the lattice of vortex-lines in type-II superconductors.

</DOC>
<DOC>
<DOCNO> 119779 </DOCNO>
An Overview of the SPOrt Experiment


  The Sky Polarization Observatory is an experiment selected by ESA for the
Early Opportunity Phase onboard the International Space Station. SPOrt is the
first payload specifically designed for polarization measurements, it will
provide near full sky maps of the sky polarized emission at four microwave
frequencies between 22 and 90 GHz. Current design of SPOrt will be presented,
together with an overview of the scientific goals of the experiment.

</DOC>
<DOC>
<DOCNO> 39798 </DOCNO>
Single-spin Azimuthal Asymmetries in the ``Reduced Twist-3


  We consider the single-spin azimuthal asymmetries recently measured at the
HERMES experiment for charged pions produced in semi-inclusive deep inelastic
scattering of leptons off longitudinally polarized protons. Guided by the
experimental results and assuming a vanishing twist-2 transverse quark spin
distribution in the longitudinally polarized nucleon, denoted as ``reduced
twist-3 approximation'', a self-consistent description of the observed
single-spin asymmetries is obtained. In addition, predictions are given for the
z dependence of the single target-spin asymmetry.

</DOC>
<DOC>
<DOCNO> 71205 </DOCNO>
Interplay between perturbative and non-perturbative effects in the


  We study corrections to electroweak precision variables in a model with
strongly interacting singlet Higgs particles.

</DOC>
<DOC>
<DOCNO> 123236 </DOCNO>
Optical Seeing and Infrared Atmospheric Transparency in the Upper


  With plans to build a large IR/optical telescope in the Atacama Desert, a
site survey campaign has been underway since 1998 to characterize the optical
seeing and the IR transparency in the Chajnantor Plateau region. Preliminary
results indicate that the Chajnantor region offers excellent astronomical
observing conditions in the optical and IR. The region is isolated yet easy to
reach, and high quality services are available nearby. We can expect to find:
median optical FWHM seeing approaching values of 0.5"--0.6", a percentage of
photometric nights of 65% or better, of astronomically useful nights in excess
of 80% and median PWV well below 1 mm (with best quartile below 0.5 mm).

</DOC>
<DOC>
<DOCNO> 99293 </DOCNO>
Divisorial linear algebra of normal semigroup rings


  We investigate the minimal number of generators $\mu$ and the depth of
divisorial ideals over normal semigroup rings. Such ideals are defined by the
inhomogeneous systems of linear inequalities associated with the support
hyperplanes of the semigroup. The main result is that for every bound $C$ there
exist, up to isomorphism, only finitely divisorial ideals $I$ such that
$\mu(I)\le C$. It follows that there exist only finitely many Cohen--Macaulay
divisor classes. Moreover we determine the minimal depth of all divisorial
ideals and the behaviour of $\mu$ and depth in ``arithmetic progressions'' in
the divisor class group.
  The results are generalized to more general systems of linear inequalities
whose homogeneous versions define the semigroup in a not necessarily
irredundant way. The ideals arising this way can also be considered as defined
by the non-negative solutions of an inhomogeneous system of linear diophantine
equations.
  We also give a more ring-theoretic approach to the theorem on minimal number
of generators of divisorial ideals: it turns out to be a special instance of a
theorem on the growth of multigraded Hilbert functions.

</DOC>
<DOC>
<DOCNO> 151155 </DOCNO>
On Harmonic Superspaces and Superconformal Fields in Four Dimensions


  Representations of four-dimensional superconformal groups on harmonic
superfields are discussed. It is shown how various short representations can be
obtained by parabolic induction. It is also shown that such short multiplets
may admit several descriptions as superfields on different superspaces. In
particular, this is the case for on-shell massless superfields. This allows a
description of short representations as explicit products of fundamental
fields. Superconformal transformations of analytic fields in real harmonic
superspaces are given explicitly.

</DOC>
<DOC>
<DOCNO> 70137 </DOCNO>
Predicting D -> sigma pi


  We examine the D -> sigma pi amplitude through a constituent quark-meson
model, incorporating heavy quark and chiral symmetries, finding a good
agreement with the recent E791 data analysis of D -> 3 pi via sigma.

</DOC>
<DOC>
<DOCNO> 67815 </DOCNO>
B Meson Transitions into Higher Mass Charmed Resonances


  We use QCD sum rules to estimate the universal form factors describing the
semileptonic B decays into excited charmed resonances, such as the $1^-$ and
$2^-$ states $D_1^{*}$ and $D_2^{*}$ belonging to the $s_\ell^P={3/2}^-$ heavy
quark doublet, and the $2^-$ and $3^-$ states $D_2^{*\prime}$ and $D_3$
belonging to the $s_\ell^P={5\2}^-$ doublet.

</DOC>
<DOC>
<DOCNO> 11971 </DOCNO>
Axial Anomaly Effect in Chiral p-wave Superconductor


  We analyze the chiral p-wave superconductor in the low temperature region.
The superconductor has a epsilon_{x} p_{x} + i epsilon_{y} p_{y}-wave gap in
two dimensional space (2D). Near the second superconducting transition point,
the system could be described by a quasi-1D chiral p-wave model in 2D. The
axial anomaly occurs in such a model and causes an accumulation of the
quasiparticle in an inhomogeneous magnetic field. The effect is related to the
winding number of the gap.

</DOC>
<DOC>
<DOCNO> 178504 </DOCNO>
Dispersive effects in neutron matter superfluidity


  The explicit energy dependence of the single particle self-energy (dispersive
effects), due to short range correlations, is included in the treatment of
neutron matter superfluidity. The method can be applied in general to strong
interacting fermion systems, and it is expected to be valid whenever the
pairing gap is substantially smaller than the Fermi kinetic energy. The results
for neutron matter show that dispersive effects are strong in the density
region near the gap closure.

</DOC>
<DOC>
<DOCNO> 121811 </DOCNO>
Dust disks around old Pre Main-Sequence stars: HST/NICMOS2 scattered


  We present recent near-infrared detections of circumstellar disks around the
two old PMS Herbig stars HD 141569 and HD 100546 obtained with the HST/NICMOS2
camera. They reveal extended structures larger than 350-400 AU in radius. While
the HD 100546 disk appears as a continuous disk down to 40 AU, the HD 141569
environment seems more complex, splitted at least into two dust populations. As
a convincing example, the full modeling of the disk surrounding HR 4796,
another old PMS star, is detailed and confronted with more recent observations.

</DOC>
<DOC>
<DOCNO> 8294 </DOCNO>
Static magnetization induced by time-periodic fields with zero mean


  We consider a single spin in a constant magnetic field or an anisotropy
field. We show that additional external time-periodic fields with zero mean may
generate nonzero time-averaged spin components which are vanishing for the
time-averaged Hamiltonian. The reason is a lowering of the dynamical symmetry
of the system. A harmonic signal with proper orientation is enough to display
the effect. We analyze the problem both with and without dissipation, both for
quantum spins (s=1/2,1) and classical spins. The results are of importance for
controlling the system's state using high or low frequency fields and for using
new resonance techniques which probe internal system parameters, to name a few.

</DOC>
<DOC>
<DOCNO> 69257 </DOCNO>
Tunneling into the Randall-Sundrum Brane World


  We suggest a modification of the Randall-Sundrum scenario which doesn't
involve branes with the negative tensions. In our scenario four-dimensional
brane world is produced by the external field. The probability of this process
is calculated and the physical features of the model are discussed.

</DOC>
<DOC>
<DOCNO> 101173 </DOCNO>
Foata's Bijection for Tree-Like Structures


  We present bijections enumerating (k,m)-trees, k-gon trees, edge labelled
(2,1)-trees, and other tree-like structures. Our constructions are based on
Foata's (1971) bijection for cycle-free functions, which is simplified here.

</DOC>
<DOC>
<DOCNO> 11756 </DOCNO>
Mesoscopic superconductors in the London limit: equilibrium properties


  We present a study of the behaviour of metastable vortex states in mesoscopic
superconductors. Our analysis relies on the London limit within which it is
possible to derive closed analytical expressions for the magnetic field and the
Gibbs free energy. We consider in particular the situation where the vortices
are symmetrically distributed along a closed ring. There, we obtain expressions
for the confining Bean-Livingston barrier and for the magnetization which turns
out to be paramagnetic away from thermodynamic equilibrium. At low temperature,
the barrier is high enough for this regime to be observable. We propose also a
local description of both thermodynamic and metastable states based on
elementary topological considerations; we find structural phase transitions of
vortex patterns between these metastable states and we calculate the
corresponding critical fields.

</DOC>
<DOC>
<DOCNO> 118016 </DOCNO>
AGB evolution with overshoot: hot bottom burning and dredge up


  We calculated models of massive AGB stars with a self-consistent coupling of
time-dependent mixing and nuclear burning for 30 isotopes and 74 reactions.
Overshoot with an exponentially declining velocity field was considered and
applied during all stages of evolution and in all convective regions. Very
efficient 3rd dredge-up was found even overcompensating the growth of the
hydrogen-exhausted core after a few thermal pulses. Hot bottom burning occurs
for M>4Msol within the sequences with overshoot. Carbon star formation in these
more massive AGB stars is delayed or even prevented by hot bottom burning
despite the very efficient dredge-up. With the simultaneous treatment of mixing
and burning the formation of Li-rich AGB stars due to the Cameron-Fowler
mechanism was followed. For a 6Msol model the maximum Li abundance was found to
be epsilon(Li7)=4.4.

</DOC>
<DOC>
<DOCNO> 169687 </DOCNO>
Entanglement measures and the Hilbert-Schmidt distance


  In order to construct a measure of entanglement on the basis of a
``distance'' between two states, it is one of desirable properties that the
``distance'' is nonincreasing under every completely positive trace preserving
map. Contrary to a recent claim, this letter shows that the Hilbert-Schmidt
distance does not have this property.

</DOC>
<DOC>
<DOCNO> 13939 </DOCNO>
Learning effective amino acid interactions through iterative stochastic


  The prediction of the three-dimensional structures of the native state of
proteins from the sequences of their amino acids is one of the most important
challenges in molecular biology. An essential ingredient to solve this problem
within coarse-grained models is the task of deducing effective interaction
potentials between the amino acids. Over the years several techniques have been
developed to extract potentials that are able to discriminate satisfactorily
between the native and non-native folds of a pre-assigned protein sequence. In
general, when these potentials are used in actual dynamical folding
simulations, they lead to a drift of the native structure outside the
quasi-native basin. In this study, we present and validate an approach to
overcome this difficulty. By exploiting several numerical and analytical tools
we set up a rigorous iterative scheme to extract potentials satisfying a
pre-requisite of any viable potential: the stabilization of proteins within
their native basin (less than 3-4 \AA$ $ cRMS). The scheme is flexible and is
demonstrated to be applicable to a variety of parametrizations of the energy
function and provides, in each case, the optimal potentials.

</DOC>
<DOC>
<DOCNO> 101695 </DOCNO>
Reflexive subgroups of the Baer-Specker group and Martin's axiom


  In two recent papers (math.LO/0003164 and math.LO/0003165) we answered a
question raised in the book by Eklof and Mekler (p. 455, Problem 12) under the
set theoretical hypothesis of diamondsuit_{aleph_1} which holds in many models
of set theory, respectively of the special continuum hypothesis (CH). The
objects are reflexive modules over countable principal ideal domains R, which
are not fields. Following H.Bass, an R-module G is reflexive if the evaluation
map s:G ---> G^{**} is an isomorphism. Here G^*=Hom(G,R) denotes the dual
module of G. We proved the existence of reflexive R-modules G of infinite rank
with G not cong G+R, which provide (even essentially indecomposable) counter
examples to the question mentioned above. Is CH a necessary condition to find
`nasty' reflexive modules? In the last part of this paper we will show
(assuming the existence of supercompact cardinals) that large reflexive modules
always have large summands. So at least being essentially indecomposable needs
an additional set theoretic assumption. However the assumption need not be CH
as shown in the first part of this paper. We will use Martin's axiom to find
reflexive modules with the above decomposition which are submodules of the
Baer-Specker module R^omega.

</DOC>
<DOC>
<DOCNO> 9309 </DOCNO>
Formation of Directed Beams from Atom Lasers


  The problem of creating well-collimated beams of atoms escaping from a trap
is studied. This problem is of high importance for the realization of atom
lasers. Nonadiabatic dynamics of neutral atoms in nonuniform magnetic fields,
typical of quadrupole magnetic traps, has been considered. The main result of
this report is that an unusual semiconfining regime of motion is found, when
atoms are confined from one side of an axis but are not confined from another
side. This regime can be achieved by means of only magnetic fields. The formed
atomic beam can be forwarded in arbitrary direction.

</DOC>
<DOC>
<DOCNO> 9659 </DOCNO>
Ground state properties of the 2D disordered Hubbard model


  We study the ground state of the two-dimensional (2D) disordered Hubbard
model by means of the projector quantum Monte Carlo (PQMC) method. This
approach allows us to investigate the ground state properties of this model for
lattice sizes up to $10 \times 10$, at quarter filling, for a broad range of
interaction and disorder strengths. Our results show that the ground state of
this system of spin-1/2 fermions remains localised in the presence of the
short-ranged Hubbard interaction.

</DOC>
<DOC>
<DOCNO> 118249 </DOCNO>
A wavelet analysis of QSO spectra


  The temperature of the intergalactic medium (IGM) is an important factor in
determining the line-widths of the absorption lines in the Lyman-alpha forest.
We present a method to characterise the line-widths distribution using a
decomposition of a Lyman-alpha spectrum in terms of discrete wavelets. Such
wavelets form an orthogonal basis so the decomposition is unique. We
demonstrate using hydrodynamic simulations that the mean and dispersion of the
wavelet amplitudes is strongly correlated with both the temperature of the
absorbing gas and its dependence on the gas density. Since wavelets are also
localised in space, we are able to analyse the temperature distribution as a
function of position along the spectrum. We illustrate how this method could be
used to identify fluctuations in the IGM temperature which might result from
late reionization or local effects.

</DOC>
<DOC>
<DOCNO> 119542 </DOCNO>
LWS spectroscopy of the luminous Blue Compact Galaxy Haro 11


  We present far infrared (FIR) spectroscopy of the luminous blue compact
galaxy (BCG) Haro 11 (ESO 350-IG38) obtained with the ISO Long Wavelength
Spectrometer (LWS) in low resolution mode. This metal poor dwarf merger is an
extremely hot IRAS source with a high [CII]158um/CO(1-0) flux ratio. We discuss
the balance between dust and line cooling in the photodissociated regions
(PDR), in particular the role of the [CII] line, and derive the basic
properties of the PDR gas. While samples of other starburst galaxies show a
correlation between the [CII]/FIR flux ratio and the IRAS f60/f100 ratio, Haro
11 deviates significantly from this relationship being brighter in [CII] than
average. We propose that the relationship is caused by an increasing optical
depth with increasing IRAS temperature but that the low metallicity and the
extreme starburst properties of Haro 11 allow the medium to be thin despite its
high f60/f100 ratio, explaining the [CII] excess. This leaves room for a more
optimistic view on the possibilities to detect massive starforming mergers at
high redshifts, using the [CII] line.

</DOC>
<DOC>
<DOCNO> 170549 </DOCNO>
Quantum Walk on the Line


  Motivated by the immense success of random walk and Markov chain methods in
the design of classical algorithms, we consider_quantum_ walks on graphs. We
analyse in detail the behaviour of unbiased quantum walk on the line, with the
example of a typical walk, the ``Hadamard walk''. We show that after t time
steps, the probability distribution on the line induced by the Hadamard walk is
almost uniformly distributed over the interval [-t/sqrt(2),t/sqrt(2)]. This
implies that the same walk defined on the circle mixes in_linear_ time. This is
in direct contrast with the quadratic mixing time for the corresponding
classical walk. We conclude by indicating how our techniques may be applied to
more general graphs.

</DOC>
<DOC>
<DOCNO> 174609 </DOCNO>
Dynamics of Heavy-Ion Collisions at Fermi Energies: Challenges and


  The dynamics of heavy-ion reactions at Fermi energies is dominated by a
dissipative mechanism modified by the concurrent emission of non-statistical
nucleons, light particles, and nuclear clusters. Experimental observables are
available to monitor the relaxation processes driving the evolution of an
interacting nuclear system towards equilibrium. Isospin degrees of freedom
provide interesting new access to fundamental information on the reaction
mechanism and the effective in-medium nucleonic interactions.

</DOC>
<DOC>
<DOCNO> 116564 </DOCNO>
About the Dependence of the Currency Exchange Rate at Time and National


  The time dependence of the currency exchange rate K treated as a function of
national dividend, investments and difference between total demand for a goods
and supply is considered. To do this a proposed earlier general algorithm of
economic processes describing on the basis of the equations for K like the
equations of statistical physics of open systems is used. A number of
differential equations (including nonlinear ones too) determining the time
dependence of the exchange rate (including oscillations) is obtained.

</DOC>
<DOC>
<DOCNO> 102065 </DOCNO>
Embeddings of hypersurfaces in affine spaces


  In this paper, we address the following two general problems: given two
algebraic varieties in ${\bf C}^n$, find out whether or not they are (1)
isomorphic; (2) equivalent under an automorphism of ${\bf C}^n$. Although a
complete solution of either of these problems is out of the question at this
time, we give here some handy and useful invariants of isomorphic as well as of
equivalent varieties. Furthermore, and more importantly, we give a universal
procedure for obtaining all possible algebraic varieties isomorphic to a given
one, and use it to construct numerous examples of isomorphic, but inequivalent
algebraic varieties in ${\bf C}^n$.
 Among other things, we establish the following interesting fact: for
isomorphic hypersurfaces $\{p(x_1,...,x_n)=0\}$ and $\{q(x_1,...,x_n)=0\}$, the
number of zeros of $grad(p)$ might be different from that of $grad(q)$.

</DOC>
<DOC>
<DOCNO> 118965 </DOCNO>
A Possible Cepheid-Like Luminosity Estimator for the Long Gamma-Ray


  We present a possible Cepheid-like luminosity estimator for the long
gamma-ray bursts based on the variability of their light curves. To construct
the luminosity estimator, we use CGRO/BATSE data for 13 bursts, Wind/KONUS data
for 5 bursts, Ulysses/GRB data for 1 burst, and NEAR/XGRS data for 1 burst.
Spectroscopic redshifts, peak fluxes, and high resolution light curves are
available for 11 of these bursts; partial information is available for the
remaining 9 bursts. We find that the isotropic-equivalent luminosities L of
these bursts positively correlate with a rigorously-constructed measure V of
the variability of their light curves. We fit a model to these data that
accommodates both intrinsic scatter (statistical variance) and extrinsic
scatter (sample variance). If one excludes GRB 980425 from the fit on the
grounds that its association with SN 1998bw at a redshift of z = 0.0085 is not
secure, the luminosity estimator spans approx. 2.5 orders of magnitude in L,
and the slope of the correlation between L and V is positive with a probability
of 1 - 1.4 x 10^-4 (3.8 sigma). Although GRB 980425 is excluded from this fit,
its L and V values are consistent with the fitted model, which suggests that
GRB 980425 may well be associated with SN 1998bw, and that GRB 980425 and the
cosmological bursts may share a common physical origin. If one includes GRB
980425 in the fit, the luminosity estimator spans approx. 6.3 orders of
magnitude in L, and the slope of the correlation is positive with a probability
of 1 - 9.3 x 10^-7 (4.9 sigma). Independently of whether or not GRB 980425
should be included in the fit, its light curve is unique in that it is much
less variable than the other approx. 17 light curves in our sample for which
the signal-to-noise is reasonably good.

</DOC>
<DOC>
<DOCNO> 152470 </DOCNO>
A Six Vertex Model on a Fishnet


  The flow of U(1) charge through dense fishnet diagrams, in a non-hermitian
matrix scalar field theory g_1Tr(\Sigma^\dagger\Sigma)^2 +
2g_1vTr\Sigma^{\dagger 2}\Sigma^2, is described by a 6-vertex model on a
``diamond'' lattice [1]. We give a direct calculation of the continuum
properties of the 6-vertex model on this novel lattice, explicitly confirming
the conclusions of [1], that, for 1/2 < v< \infty, they are identical to those
of a world-sheet scalar field compactified on a circle S_1. The radius of the
circle is related to the ratio v of quartic couplings by R^{-2} = 2T_0
arccos(1-1/2v^2). This direct computational approach may be of value in
generalizing the conclusions to the non-Abelian O(n) case.

</DOC>
<DOC>
<DOCNO> 9117 </DOCNO>
An Explicit Form of the Equation of Motion of the Interface in


  The explicit form of the interface equation of motion derived assuming a
minimal surface is extended to general bicontinuous interfaces that appear in
the diffusion limited stage of the phase separation process of binary mixtures.
The derivation is based on a formal solution of the equivalent simple layer for
the Dirichlet problem of the Laplace equation with an arbitrary boundary
surface. It is shown that the assumption of a minimal surface used in the
previous linear theory is not necessary, but its bicontinuous nature is the
essential condition required for us to rederive the explicit form of the simple
layer. The de- rived curvature flow equation has a phenomenological cut-off
length, i.e., an `electro-static' screening length. That is re- lated to the
well-known scaling length characterizing the spatial pattern size of a
homogeneously growing bicontinuous phase. The corresponding equation of the
level function in this scheme is given in a one-parameter form also.

</DOC>
<DOC>
<DOCNO> 123180 </DOCNO>
Galactic Black HOle Binary Systems


  I review observations of the X-ray spectra of Galactic Black Hole Candidates,
and theoretical ideas as to how these can be produced. X-ray reflection should
enable different source geometries to be distinguished, but the ionisation
instability of X-ray irradiated material in hydrostatic equilibrium gives rise
to large ambiguities in interpretation. It is not currently possible to
determine whether the underlying emission mechanism in the low state is an
advective flow or magnetic reconnection above the disk, but more detailed
modelling of the ionisation instability {\it may} allow us to distinguish
between these scenarios.

</DOC>
<DOC>
<DOCNO> 83152 </DOCNO>
A note on knowledge-based programs and specifications


  Knowledge-based program are programs with explicit tests for knowledge. They
have been used successfully in a number of applications. Sanders has pointed
out what seem to be a counterintuitive property of knowledge-based programs.
Roughly speaking, they do not satisfy a certain monotonicity property, while
standard programs (ones without tests for knowledge) do. It is shown that there
are two ways of defining the monotonicity property, which agree for standard
programs. Knowledge-based programs satisfy the first, but do not satisfy the
second. It is further argued by example that the fact that they do not satisfy
the second is actually a feature, not a problem. Moreover, once we allow the
more general class of knowledge-based specifications, standard programs do not
satisfy the monotonicity property either.

</DOC>
<DOC>
<DOCNO> 68020 </DOCNO>
Wave-Particle duality at the Planck scale: Freezing of neutrino


  A gravitationally-induced modification to de Broglie wave-particle duality is
presented. At Planck scale, the gravitationally-modified matter wavelength
saturates to a few times the Planck length in a momentum independent manner. In
certain frameworks, this circumstance freezes neutrino oscillations in the
Planck realm. This effect is apart, and beyond, the gravitational red-shift. A
conclusion is drawn that in a complete theory of quantum gravity the notions of
``quantum'' and ``gravity'' shall carry new meanings -- meanings, that are yet
to be deciphered from theory and observations in their entirety.

</DOC>
<DOC>
<DOCNO> 100612 </DOCNO>
Ideals and Formal Morita Equivalence of Algebras


  Motivated by deformation quantization, we introduced in an earlier work the
notion of formal Morita equivalence in the category of $^*$-algebras over a
ring $\ring C$ which is the quadratic extension by $\im$ of an ordered ring
$\ring R$. The goal of the present paper is twofold. First, we clarify the
relationship between formal Morita equivalence, Ara's notion of Morita
$^*$-equivalence of rings with involution, and strong Morita equivalence of
$C^*$-algebras. Second, in the general setting of $^*$-algebras over $\ring C$,
we define `closed' $^*$-ideals as the ones occuring as kernels of
$^*$-representations of these algebras on pre-Hilbert spaces. These ideals form
a lattice which we show is invariant under formal Morita equivalence. This
result, when applied to Pedersen ideals of $C^*$-algebras, recovers the
so-called Rieffel correspondence theorem. The triviality of the minimal element
in the lattice of closed ideals, called the `minimal ideal', is also a formal
Morita invariant and this fact can be used to describe a large class of
examples of $^*$-algebras over $\ring C$ with equivalent representation theory
but which are not formally Morita equivalent. We finally compute the closed
$^*$-ideals of some $^*$-algebras arising in differential geometry.

</DOC>
<DOC>
<DOCNO> 84171 </DOCNO>
Quantum extreme black holes at finite temperature and exactly solvable


  It is argued that in certain 2d dilaton gravity theories there exist
self-consistent solutions of field equations with quantum terms which describe
extreme black holes at nonzero temperature. The curvature remains finite on the
horizon due to cancelation of thermal divergencies in the stress-energy tensor
against divergencies in the classical part of field equations. The extreme
black hole solutions under discussion are due to quantum effects only and do
not have classical counterparts.

</DOC>
<DOC>
<DOCNO> 71716 </DOCNO>
Top mixing in effective theories


  We review how top mixing with light quarks constrains new physics beyond the
Standard Model using the effective Lagrangian approach.

</DOC>
<DOC>
<DOCNO> 120073 </DOCNO>
The BeppoSAX 2-10 keV Survey


  We present the results of a 2-10 keV BeppoSAX survey based on 140 high
galactic latitude MECS fields, 12 of which are deep exposures of ``blank''
parts of the sky. The limiting sensitivity is 5 10^-14 erg cm^-2 s^-1 where
about 25% of the Cosmic X-ray Background (CXB) is resolved into discrete
sources. The logN-logS function, built with a statistically complete sample of
177 sources, is steep and in good agreement with the counts derived from ASCA
surveys. A CXB fluctuation analysis allowed us to probe the logN-logS down to
about 1.5 10^-14 erg cm^-2 s^-1 where the contribution of discrete sources to
the CXB grows to 40-50%. A hardness ratio analysis reveals the presence of a
wide range of spectral shapes and that a fairly large fraction of sources
appear to be heavily absorbed, some of which showing soft components. A
comparison of the flux distribution of different subsamples confirms the
existence of a spectral hardening with decreasing flux. This effect is probably
due to an increasing percentage of absorbed sources at faint fluxes, rather
than to a gradual flattening of the spectral slope. Nearly all the sources for
which adequate ROSAT exposures exist, have been detected in the soft X-rays.
This confirms that soft spectral components are present even in strongly
absorbed objects, and that a large population of sources undetectable below a
few keV does not exist. A Ve/Va test provides evidence for the presence of
cosmological evolution of a magnitude similar to that found in soft X-ray
extragalactic sources. Evolution is present both in normal and absorbed
sources, with the latter population possibly evolving faster,although this
effect could also be the result of complex selection effects.

</DOC>
<DOC>
<DOCNO> 71146 </DOCNO>
Calculation of fragmentation functions in two-hadron semi-inclusive


  We investigate the properties of interference fragmentation functions arising
from the emission of two leading hadrons inside the same jet for inclusive
lepton-nucleon deep-inelastic scattering. Using an extended spectator model for
the mechanism of the hadronization, we give a complete calculation and
numerical estimates for the examples of a proton-pion pair produced with
invariant mass on the Roper resonance, and of two pions produced with invariant
mass close to the $\rho$ mass. We discuss azimuthal angular dependence of the
leading order cross section to point up favourable conditions for extracting
transversity from experimental data.

</DOC>
<DOC>
<DOCNO> 102565 </DOCNO>
Picard numbers in a family of hyperk\"ahler manifolds - A supplement to


  We remark the density of the jumping loci of the Picard number of a
hyperk\"ahler manifold under small one-dimensional deformation and provide some
applications for the Mordell-Weil groups of Jacobian K3 surfaces.

</DOC>
<DOC>
<DOCNO> 122713 </DOCNO>
Exploding and Non-exploding Stars: Coupling Nuclear Reaction Networks to


  After decades of one-dimensional nucleosynthesis calculations, the growth of
computational resources has meanwhile reached a level, which for the first time
allows astrophysicists to consider performing routinely realistic
multidimensional nucleosynthesis calculations in explosive and, to some extent,
also in non-explosive environments. In the present contribution we attempt to
give a short overview of the physical and numerical problems which are
encountered in these simulations. In addition, we assess the accuracy that can
be currently achieved in the computation of nucleosynthetic yields, using
multidimensional simulations of core collapse supernovae as an example.

</DOC>
<DOC>
<DOCNO> 117204 </DOCNO>
Pathways to double ionization of atoms in strong fields


  We discuss the final stages of double ionization of atoms in a strong
linearly polarized laser field within a classical model. We propose that all
trajectories leading to non-sequential double ionization pass close to a saddle
in phase space which we identify and characterize. The saddle lies in a two
degree of freedom subspace of symmetrically escaping electrons. The
distribution of longitudinal momenta of ions as calculated within the subspace
shows the double hump structure observed in experiments. Including a symmetric
bending mode of the electrons allows us to reproduce the transverse ion
momenta. We discuss also a path to sequential ionization and show that it does
not lead to the observed momentum distributions.

</DOC>
<DOC>
<DOCNO> 80720 </DOCNO>
Numerical tests of the Kugo-Ojima color confinement criterion


  The Kugo-Ojima color confinement criterion, which is based on the BRST
symmetry of QCD is numerically tested by the lattice Landau gauge simulation.
We first discuss the BRST symmetry on the lattice and the Gribov copy problem.
The horizon function defined by Zwanziger based on the U-linear definition of
the gauge field and that based on log U are compared. The parameter u which is
expected to be $-1\delta^a_b$ in the continuum theory was found to be
$-0.7\delta^a_b$ in the strong coupling region. There are about 20% difference
between the two horizon functions, but in the weak coupling region, the
expectation value of the horizon function is suggested to be zero or negative.

</DOC>
<DOC>
<DOCNO> 120676 </DOCNO>
Recent Progress in Understanding Nucleosynthesis via Rapid Neutron


  I discuss the recent progress in our understanding of nucleosynthesis via
rapid neutron capture, the r-process, based on meteoritic data for the early
solar system and observations of stars at low metallicities. At present, all
data require that there be two distinct kinds of r-process events and suggest
that supernovae are associated with these events. The diversity of supernova
sources for the r-process may depend on whether a neutron star or black hole is
formed in an individual supernova. This dependence, if substantiated by future
observations discussed here, has important implications for properties of
nuclear matter.

</DOC>
<DOC>
<DOCNO> 10395 </DOCNO>
C-axis negative magnetoresistance and upper critical field of


  The out-of-plane resistance and the resistive upper critical field of
BSCCO-2212 single crystals with Tc=91-93 K have been measured in magnetic
fields up to 50 T over a wide temperature range. The results are characterised
by a positive linear magnetoresistance in the superconducting state and a
negative linear magnetoresistance in the normal state. The zero field normal
state c-axis resistance, the negative linear normal state magnetoresistance,
and the divergent upper critical field Hc2(T)are explained in the framework of
the bipolaron theory of superconductivity.

</DOC>
<DOC>
<DOCNO> 70410 </DOCNO>
Regularizing the Divergent Structure of the Light-Front Currents


  The divergences appearing in the 3+1 dimensional fermion-loop calculations
are often regulated by smearing the vertices in a covariant manner. Performing
a parallel light-front calculation, we corroborate the similarity between the
vertex-smearing-technique and the Pauli-Villars regularization. In the
light-front calculation of the electromagnetic meson current, we find that the
persistent end-point singularity that appears in the case of point vertices is
removed even if the smeared-vertex is taken to the limit of the point-vertex.
Recapitulating the current conservation, we substantiate the finiteness of both
valence and non-valence contributions in all components of the current with the
regularized bound-state vertex. However, we stress that each contribution,
valence or non-valence, depends on the reference-frame even though the sum is
always frame-independent. The numerical taxonomy of each contribution including
the instantaneous contribution and the zero-mode contribution is presented in
the $\pi$, $K$, and $D$-meson form factors.

</DOC>
<DOC>
<DOCNO> 71920 </DOCNO>
A potential WIMP signature for the caustic ring halo model


  Weakly Interacting Massive Particle (WIMP) direct detection event rate
calculations usually rely on fairly simple, essentially static, analytic halo
models. This is largely since the resolution of numerical simulations is not
yet large enough to allow the full numerical calculation of the WIMP density
and velocity distribution. In this paper we study the direct detection rate, in
particular its energy dependence and annual modulation, for the caustic ring
halo model. In this model, which uses simple assumptions to model the infall of
dark matter onto the halo, the distribution of the cold dark matter particles
at the Earth's location has a series of peaks in velocity space. We find that
the sign of the annual modulation in the event rate changes as a function of
recoil energy. These effects provide a potentially distinctive experimental
signal.

</DOC>
<DOC>
<DOCNO> 9639 </DOCNO>
Observation of Nanometer-Scale Rolling Motion Mediated by Commensurate


  We report, through experimental observations and computer simulations, that
atomic lattice interlocking can determine whether an object rolls or slides on
a surface. We have quantitatively manipulated carbon nanotubes (CNTs) on a
variety of substrates with an atomic force microscope (AFM) and observe rolling
to occur only on graphite. We measure the forces when the CNT is in-registry
with the graphite lattice, and observe rolling only in this lock-in state.
Atomistic computer simulations identify the energy barriers for sliding and
rolling, elucidate atomic-scale features of slip-roll motion, and explain the
details of the lateral force data in terms of the intrinsic faceting of
multiwall CNTs.

</DOC>
<DOC>
<DOCNO> 122900 </DOCNO>
Power Spectrum Covariance of Weak Gravitational Lensing


  Weak gravitational lensing observations probe the spectrum and evolution of
density fluctuations and the cosmological parameters which govern them. At low
redshifts, the non-linear gravitational evolution of large scale structure
produces a non-Gaussian covariance in the shear power spectrum measurements
that affects their translation into cosmological parameters. Using the dark
matter halo approach, we study the covariance of binned band power spectrum
estimates and the four point function of the dark matter density field that
underlies it. We compare this semi-analytic estimate to results from N-body
numerical simulations and find good agreement. We find that for a survey out to
z ~ 1, the power spectrum covariance increases the errors on cosmological
parameters determined under the Gaussian assumption by about 15%.

</DOC>
<DOC>
<DOCNO> 8820 </DOCNO>
Solid-phase structures of the Dzugutov pair potential


  In recent computer simulations of a simple monatomic system interacting via
the Dzugutov pair potential, freezing of the fluid into an equilibrium
dodecagonal quasicrystal has been reported [M. Dzugutov, Phys. Rev. Lett. 70,
2924 (1993)]. Here, using a combination of molecular dynamics simulation and
thermodynamic perturbation theory, we conduct a detailed analysis of the
relative stabilities of solid-phase structures of the Dzugutov-potential
system. At low pressures, the most stable structure is found to be a bcc
crystal, which gives way at higher pressures to an fcc crystal. Although a
dodecagonal quasicrystal and a sigma-phase crystal compete with the bcc crystal
for stability, they remain always metastable.

</DOC>
<DOC>
<DOCNO> 71659 </DOCNO>
A renormalized equation for the three-body system with short-range


  We study the three-body system with short-range interactions characterized by
an unnaturally large two-body scattering length. We show that the off-shell
scattering amplitude is cutoff independent up to power corrections. This allows
us to derive an exact renormalization group equation for the three-body force.
We also obtain a renormalized equation for the off-shell scattering amplitude.
This equation is invariant under discrete scale transformations. The
periodicity of the spectrum of bound states originally observed by Efimov is a
consequence of this symmetry. The functional dependence of the three-body
scattering length on the two-body scattering length can be obtained
analytically using the asymptotic solution to the integral equation. An
analogous formula for the three-body recombination coefficient is also
obtained.

</DOC>
<DOC>
<DOCNO> 13079 </DOCNO>
Detecting fractions of electrons in the high-$T_c$ cuprates


  We propose several tests of the idea that the electron is fractionalized in
the underdoped and undoped cuprates. These include the ac Josephson effect, and
tunneling into small superconducting grains in the Coulomb blockade regime. In
both cases, we argue that the results are qualitatively modified from the
conventional ones if the insulating tunnel barrier is fractionalized. These
experiments directly detect the possible existence of the chargon - a charge
$e$ spinless boson - in the insulator. The effects described in this paper
provide a means to probing whether the undoped cuprate (despite it's magnetism)
is fractionalized. Thus, the experiments discussed here are complementary to
the flux-trapping experiment we proposed in our earlier work(cond-mat/0006481).

</DOC>
<DOC>
<DOCNO> 14018 </DOCNO>
Chromatic roots are dense in the whole complex plane


  I show that the zeros of the chromatic polynomials P_G(q) for the generalized
theta graphs \Theta^{(s,p)} are, taken together, dense in the whole complex
plane with the possible exception of the disc |q-1| < 1. The same holds for
their dichromatic polynomials (alias Tutte polynomials, alias Potts-model
partition functions) Z_G(q,v) outside the disc |q+v| < |v|. An immediate
corollary is that the chromatic zeros of not-necessarily-planar graphs are
dense in the whole complex plane. The main technical tool in the proof of these
results is the Beraha-Kahane-Weiss theorem on the limit sets of zeros for
certain sequences of analytic functions, for which I give a new and simpler
proof.

</DOC>
<DOC>
<DOCNO> 121614 </DOCNO>
Structure formation in anisotropic Einstein-Cartan cosmologies


  Density linear perturbations in Einstein-Cartan two fluid cosmologies where
the outer model is an isotropic Friedmann solution with closed model while the
inner model is a flat anisotropic Einstein-Cartan (EC) cosmology with shear are
computed by taking into consideration superhorizon situations.This situation is
in agreement with the present isotropy of the Cosmic Background Radiation where
the anisotropic EC model evolves into an isotropic general relativistic
model.Galaxy formation is discussed based on this model.Another type of two
fluid is considered where the inner solution is a pressureless Kasner type
solution while the outer solution is a de Sitter solution with spin and
torsion.

</DOC>
<DOC>
<DOCNO> 122024 </DOCNO>
The ATESP radio survey III. Source counts


  This paper is part of a series reporting the results of the ATESP radio
survey obtained at 1.4 GHz with the Australia Telescope Compact Array. The
survey consists of 16 radio mosaics with ~8"x14" resolution and uniform
sensitivity (1sigma noise level ~79 microJy) over the whole area of the ESO
Slice Project redshift survey (~26 sq. degrees at decl. = -40 degrees). The
ATESP survey has produced a catalogue of 2960 radio sources down to a flux
limit (6sigma) of ~0.5 mJy. In this paper we present the 1.4 GHz log N - log S
relation derived from the ATESP radio source catalogue. The possible causes of
incompleteness at the faint end of the source counts are extensively discussed
and their effects are quantified and corrected for. The ATESP counts are
consistent with others reported in the literature, even though some significant
discrepancies are present at low fluxes (below a few mJy). We investigate
whether such discrepancies may be explained in terms of field-to-field
anisotropies, considering the fact that all the existing sub-mJy surveys cover
small areas of sky (from a fraction of square degree to a few square degrees).
We stress that the ATESP survey, covering 26 sq. degrees, provides the best
determination of source counts available today in the flux range 0.7 <
S(1.4GHz) < 2 mJy.

</DOC>
<DOC>
<DOCNO> 117140 </DOCNO>
Thermodynamics of Substances with Negative Thermal Expansion Coefficient


  The 1st law of thermodynamics for heat exchange is dQ=dU+PdV. According to K.
Martinas etc., J. Non-Equil. Thermod. 23 (4), 351-375 (1988), for substances
with negative thermal expansion coefficient, P in this law is negative. In the
present paper it has been shown that P for such substances is positive but the
sign before P must be minus not plus: dQ=dU-PdV.

</DOC>
<DOC>
<DOCNO> 117675 </DOCNO>
Vorticity Budget of Weak Thermal Convection in Keplerian disks


  By employing the equations of mean-square vorticity (enstrophy) fluctuations
in strong shear flows, we demonstrate that unlike energy production of
turbulent vorticity in nonrotating shear flows, the turbulent vorticity of weak
convection in Keplerian disks cannot gain energy from vortex stretching/tilting
by background shear unless the asscoiated Reynolds stresses are negative. This
is because the epicyclic motion is an energy sink of the radial component of
mean-square turbulent vorticity in Keplerian disks when Reynolds stresses are
positive. Consequently, weak convection cannot be self-sustained in Keplerian
flows. This agrees with the results implied from the equations of mean-square
velocity fluctuations in strong shear flows. Our analysis also sheds light on
the explanation of the simulation result in which positive kinetic helicity is
produced by the Balbus-Hawley instability in a vertically stratified Keplerian
disk. We also comment on the possibility of outward angular momentum transport
by strong convection based on azimuthal pressure perturbations and directions
of energy cascade.

</DOC>
<DOC>
<DOCNO> 85496 </DOCNO>
Image distortion from optical scalars in non perturbative gravitational


  In a previous article concerning image distortion in non-perturbative
gravitational lensing theory we described how to introduce shape and distortion
parameters for small sources. We also showed how they could be expressed in
terms of the scalar products of the geodesic deviation vectors of the source's
pencil of rays in the past lightcone of an observer. In the present work we
give an alternative approach to the description of the shape and distortion
parameters and their evolution along the null geodesic from the source to the
observer, but now in terms of the optical scalars (the convergence and shear of
null vector field of the observer's lightcone) and the associated optical
equations, which relate the optical scalars to the curvature of the spacetime.

</DOC>
<DOC>
<DOCNO> 120969 </DOCNO>
An HST Lensing Survey of X-ray Luminous Galaxy Clusters: I. A383


  We analyse the mass distribution in the core of A383 (z=0.188), one of 12
X-ray luminous clusters at z~0.2 selected for a comprehensive and unbiased
study of the mass distribution in massive clusters. Deep HST imaging reveals a
wide variety of gravitationally lensed features in A383, including a giant arc
formed from the strongly-lensed images of 2 background galaxies, 2 radial arcs,
several multiply-imaged arcs and numerous arclets. Based upon the constraints
from the various lensed features, we construct a detailed mass model for the
central regions of the cluster, taking into account both the cluster-scale
potential and perturbations from individual cluster galaxies. Keck spectroscopy
of one component of the giant arc identifies it as a star-forming galaxy at
z=1.01 and provides an accurate measurement of the cluster mass within the
radius of the giant arc (65kpc) of (3.5+/-0.1)*10^13 Mo. Using the weak shear
measured from our HST observations we extend our mass model to determine a mass
of (1.8+/-0.2)*10^14 Mo within a radius of 250kpc. On smaller scales we employ
the radial arcs as probes of the shape of the mass distribution in the cluster
core (r<20kpc), and find that the mass profile is more peaked than a single NFW
profile. The optical and X-ray properties of A383 indicate the presence of a
central cooling flow, for which we derive a mass deposition rate of >200 Mo/yr.
We also use the X-ray emission from A383 to obtain independent estimates of the
total mass within projected radii of 65 and 250kpc: (4.0+/-1.4)*10^13 Mo and
(1.2+/-0.5)*10^14 Mo, which are consistent with the lensing measurements.
[Abridged]

</DOC>
<DOC>
<DOCNO> 118221 </DOCNO>
The Formation of Galaxies, the Formation of Old Globular Clusters and


  In this paper, we are exploring the properties of old, metal-poor globular
clusters in galaxies. We investigate whether their properties are related to
the properties of their host galaxies, and whether we can constrain their
formation. The main result is that the mean metallicities of old GC systems are
found to lie in a narrow range -1.7 < [Fe/H] < -1.1 (80 % of the population).
Moreover, no correlations are found between the mean metallicities and other
galaxy properties which implies a GC formation independent of the host
galaxies. Further, we try to identify the sites of old, metal-poor GC
formation, with any currently known high redshift objects. We find that the
metalicities of damped Ly$\alpha$ systems in the redshift range 1.6 < z < 4 are
consistent with our GC metalicities, which suggests that these high-density
neutral gas objects may be the progenitors of the old, metal-poor globular
clusters.

</DOC>
<DOC>
<DOCNO> 85088 </DOCNO>
Perturbative Noncommutative Quantum Gravity


  We study perturbative noncommutative quantum gravity by expanding the
gravitational field about a fixed classical background. A calculation of the
one loop gravitational self-energy graph reveals that only the non-planar
graviton loops are damped by oscillating internal momentum dependent factors.
The noncommutative quantum gravity perturbation theory is not renormalizable
beyond one loop for matter-free gravity and all loops for matter interactions.
Comments are made about the nonlocal gravitational interactions produced by the
noncommutative spacetime geometry.

</DOC>
<DOC>
<DOCNO> 99620 </DOCNO>
On the Structure of Submanifolds with Degenerate Gauss Mappings


  An n-dimensional submanifold X of a projective space P^N (C) is called
tangentially degenerate if the rank of its Gauss mapping \gamma: X ---> G (n,
N) satisfies 0 < rank \gamma < n.
  The authors systematically study the geometry of tangentially degenerate
submanifolds of a projective space $P^N (\mathbf{C})$. By means of the focal
images, three basic types of submanifolds are discovered: cones, tangentially
degenerate hypersurfaces, and torsal submanifolds. Moreover, for tangentially
degenerate submanifolds, a structural theorem is proven. By this theorem,
tangentially degenerate submanifolds that do not belong to one of the basic
types are foliated into submanifolds of basic types. In the proof the authors
introduce irreducible, reducible, and completely reducible tangentially
degenerate submanifolds. It is found that cones and tangentially degenerate
hypersurfaces are irreducible, and torsal submanifolds are completely reducible
while all other tangentially degenerate submanifolds not belonging to basic
types are reducible.

</DOC>
<DOC>
<DOCNO> 101210 </DOCNO>
3-Sasakian Geometry, Nilpotent Orbits, and Exceptional Quotients


  Using 3-Sasakian reduction techniques we obtain infinite families of new
3-Sasakian manifolds $\scriptstyle{{\cal M}(p_1,p_2,p_3)}$ and
$\scriptstyle{{\cal M}(p_1,p_2,p_3,p_4)}$ in dimension 11 and 15 respectively.
The metric cone on $\scriptstyle{{\cal M}(p_1,p_2,p_3)}$ is a generalization of
the Kronheimer hyperk\"ahler metric on the regular maximal nilpotent orbit of
$\scriptstyle{{\Got s}{\Got l}(3,\bbc)}$ whereas the cone on
$\scriptstyle{{\cal M}(p_1,p_2,p_3,p_4)}$ generalizes the hyperk\"ahler metric
on the 16-dimensional orbit of $\scriptstyle{{\Got s}{\Got o}(6,\bbc)}$. These
are first examples of 3-Sasakian metrics which are neither homogeneous nor
toric. In addition we consider some further $\scriptstyle{U(1)}$-reductions of
$\scriptstyle{{\cal M}(p_1,p_2,p_3)}$. These yield examples of non-toric
3-Sasakian orbifold metrics in dimensions 7. As a result we obtain explicit
families $\scriptstyle{{\cal O}(\Theta)}$ of compact self-dual positive scalar
curvature Einstein metrics with orbifold singularities and with only one
Killing vector field.

</DOC>
<DOC>
<DOCNO> 11730 </DOCNO>
Fermionic Heisenberg Glasses with BCS Pairing Interaction


  We have analyzed a fermionic infinite-ranged quantum Heisenberg spin glass
with BCS coupling in real space in the presence of a magnetic field. It has
been possible to locate the transition line between the normal paramagnetic
phase (NP) and the phase where there is a long range order corresponding to
pair formation in sites (PAIR). The nature of the transition line is also
investigated. This transition ends at Tf, the transition temperature between NP
and spin glass phase (SG) where the static approximation and replica symmetry
ansatz are reliable.

</DOC>
<DOC>
<DOCNO> 12765 </DOCNO>
Weak coupling renormalization-group analysis of two-dimensional Hubbard


  We present a weak coupling renormalization-group analysis of the Hubbard
model on the anisotropic triangular lattice. As the model interpolates between
the nearest-neighbor square lattice and decoupled chains via the isotropic
triangular lattice, it permits the study of competition between
antiferromagnetic and BCS Cooper instabilities. We begin by reproducing known
results for decoupled chains, and for the square lattice with only
nearest-neighbor hopping amplitude $t_1$. We examine both repulsive and
attractive Hubbard interactions. The role of formally irrelevant contributions
to the one-loop renormalization-group flows is also studied, and these
subleading contributions are shown to be important in some instances. We then
demonstrate that crossover to a BCS-dominated regime can occur even at
half-filling when antiferromagnetism is frustrated via the introduction of a
next-nearest-neighbor hopping amplitude $t_2$ along one of the two diagonal
directions. The resulting anisotropic triangular lattice may describe the
conducting layers of the organic $\kappa-(BEDT-TTF)_2X$ materials. Stripes are
not expected to occur and time-reversal breaking $d_{x^2 - y^2} \pm i d_{xy}$
superconducting order does not arise spontaneously; instead pure $d_{x^2 -
y^2}$ order is favored. At the isotropic triangular point ($t_1 = t_2$) we find
the possibility of re-entrant antiferromagnetic long-range order.

</DOC>
<DOC>
<DOCNO> 69152 </DOCNO>
Semi-Leptonic B Meson Decays to Excited D Mesons in the Covariant


  The spectra and branching ratios of the weak semi-leptonic B meson decays to
the first excited D mesons are predicted, taking into account the confined
effects of quarks using the covariant oscillator quark model (COQM). In the
COQM the same relation between general weak transition form factors as that in
HQET is derived, and the concrete form of the Isgur-Wise function is given with
no free parameters. Our results are somewhat different from those of other
models. The present experimental data are not sufficient for comparison.

</DOC>
<DOC>
<DOCNO> 40406 </DOCNO>
Nuclear Physics at the TESLA*HERA Complex


  Construction of the TESLA linear electron-positron collider tangentially to
the HERA proton ring will provide a number of new facilities for particle and
nuclear physics research. In this paper main parameters and physics goals of
eA, gamma-A and FEK gamma-A colliders, as well as fixed target experiments are
discussed.

</DOC>
<DOC>
<DOCNO> 13089 </DOCNO>
An overview on the phase diagram of the frustrated two-leg ladder model


  Using Density-Matrix Renormalization Group, we investigate the general phase
diagram of the frustrated two-leg ladder with Heisenberg interactions along
legs, rungs and diagonals. We confirm that all antiferromagnetic gapped states
belong to the same universality class as the Haldane phase. In a
three-dimensional phase diagram, we determine a continuous surface with
singularities in the string-order parameter or its first derivative,
corresponding to a transition between two Haldane phases with different
topological order. Some parts of this transition surface are critical with zero
gap and vanishing string-order parameter. In the complementary parts, the
transition is first order with finite gap and string order. The boundary of
this surface with the ferromagnetic region is a critical end line, when the
surface is critical and a triple line anywhere else. Part of this boundary
coincides with the exactly soluble model proposed by D.V. Dmitriev, V. Ya
Krivnov and A.A. Ovchinnikov [Phys. Rev. B 56, 5985 (1997)].

</DOC>
<DOC>
<DOCNO> 12801 </DOCNO>
Stability analysis of static solutions in a Josephson junction


  We present all the possible solutions of a Josephson junction with bias
current and magnetic field with both inline and overlap geometry, and examine
their stability. We follow the bifurcation of new solutions as we increase the
junction length. The analytical results, in terms of elliptic functions in the
case of inline geometry, are in agreement with the numerical calculations and
explain the strong hysteretic phenomena typically seen in the calculation of
the maximum tunneling current. This suggests a different experimental approach
based on the use, instead of the external magnetic field the modulus of the
elliptic function or the related quantity the total magnetic flux to avoid
hysteretic behavior and unfold the overlapping $I_{max}(H)$ curves.

</DOC>
<DOC>
<DOCNO> 123284 </DOCNO>
Cluster AgeS Experiment: The Age and Distance of the Globular Cluster


  We use masses, radii, and luminosities of the detached eclipsing binary
OGLEGC17 derived from photometric and spectroscopic observations to calculate
the age and distance of the globular cluster omega Cen. Age versus turnoff mass
and age versus luminosity relations from Girardi et al. (2000) yield two
independent estimates of the age, 9.1<t<16.7 Gyr and 12.9<t<18.5 Gyr. The
distance and distance modulus derived by use of the infrared versus surface
brightness relation are d =5385+-300 pc and (m-M)_V=14.06+-0.11. Distances
derived from our infrared surface brightness versus color relation and the Teff
versus B-V color relation of Sekiguchi & Fukugita (2000) disagree by about 10
per cent. Major improvements in the accuracy in estimated age and distance can
be made with better measurements of the masses of the components of OGLEGC17.

</DOC>
<DOC>
<DOCNO> 70466 </DOCNO>
Natural Quintessence?


  We formulate conditions for the naturalness of cosmological quintessence
scenarios. The quintessence lagrangian is taken to be the sum of a simple
exponential potential and a non-canonical kinetic term. This parameterization
covers most variants of quintessence and makes the naturalness conditions
particularly transparent. Several ``natural'' scalar models lead, for the
present cosmological era, to a large fraction of homogeneous dark energy
density and an acceleration of the scale factor as suggested by observation.

</DOC>
<DOC>
<DOCNO> 9059 </DOCNO>
Exact Solution for the Critical State in Thin Superconductor Strips with


  An exact analytical solution is given for the critical state problem in long
thin superconductor strips in a perpendicular magnetic field, when the critical
current density j_c(B) depends on the local induction B according to a simple
three-parameter model. This model describes both isotropic superconductors with
this j_c(B) dependence, but also superconductors with anisotropic pinning
described by a dependence j_c(theta) where theta is the tilt angle of the flux
lines away from the normal to the specimen plane.

</DOC>
<DOC>
<DOCNO> 122268 </DOCNO>
Inverse cascade in decaying 3D magnetohydrodynamic turbulence


  We perform direct numerical simulations of three-dimensional freely decaying
magnetohydrodynamic (MHD) turbulence. For helical magnetic fields an inverse
cascade effect is observed in which power is transfered from smaller scales to
larger scales. The magnetic field reaches a scaling regime with self-similar
evolution, and power law behavior at high wavenumbers. We also find power law
decay in the magnetic and kinematic energies, and power law growth in the
characteristic length scale of the magnetic field.

</DOC>
<DOC>
<DOCNO> 101589 </DOCNO>
The C*-algebras of arbitrary graphs


  To an arbitrary directed graph we associate a row-finite directed graph whose
C*-algebra contains the C*-algebra of the original graph as a full corner. This
allows us to generalize results for C*-algebras of row-finite graphs to
C*-algebras of arbitrary graphs: the uniqueness theorem, simplicity criteria,
descriptions of the ideals and primitive ideal space, and conditions under
which a graph algebra is AF and purely infinite. Our proofs require only
standard Cuntz-Krieger techniques and do not rely on powerful constructs such
as groupoids, Exel-Laca algebras, or Cuntz-Pimsner algebras.

</DOC>
<DOC>
<DOCNO> 121330 </DOCNO>
Radio cores in blazars


  We present results and first epoch parsec-scale images from a monitoring
program on five $\gamma$--ray loud blazars selected on the basis of their total
flux density variability. We observed 0048$-$097, 0235+164, 0954+658,
1510$-$089 and 1749+096 with the Very Long Baseline Array simultaneously at 8.4
GHz and 22 GHz. Comparison between our high quality images and previous results
from the literature suggest that 0954+658 and 1510$-$089 are superluminal radio
sources, with a Lorentz factor $\gamma$ of the order of $\sim 2 - 3$.

</DOC>
<DOC>
<DOCNO> 117904 </DOCNO>
Nucleosynthesis in Chandrasekhar Mass Models for Type Ia Supernovae and


  We calculate explosive nucleosynthesis in Chandrasekhar mass models for Type
Ia Supernovae(SNe Ia) to obtain new constraints on the rate of matter accretion
onto the progenitor white dwarf and on the ignition density of central carbon
deflagration. The calculated abundance of the Fe-group neutron-rich nuclei is
highly sensitive to the electron captures taking place in the central layers.
The yields obtained from a slow central deflagration, and from a fast
deflagration or delayed detonation in the outer layers, are combined and put to
comparison with solar isotopic abundances. We found that (1) to avoid too large
ratios of $^{54}$Cr/$^{56}$Fe and $^{50}$Ti/$^{56}$Fe, the ignition density
should be as low as \ltsim 2 \e9 \gmc, and that (2) to avoid the overproduction
of $^{58}$Ni and $^{54}$Fe, either the flame speed should not exceed a few % of
the sound speed in the central low $Y_e$ layers, or the progenitor star has to
be metal-poor compared with solar. Such low central densities can be realized
by a rapid accretion as fast as $\dot M$ \gtsim 1 $\times$ 10$^{-7}$M$_\odot$
yr$^{-1}$. In order to reproduce the solar abundance of $^{48}$Ca, one also
needs progenitor systems that undergo ignition at higher densities. We also
found that the total amount of $^{56}$Ni, the Si-Ca/Fe ratio, and the abundance
of elements like Mn and Cr (incomplete Si-burning ashes), depend on the density
of the deflagration-detonation transition in delayed detonations. Our
nucleosynthesis results favor transition densities slightly below 2.2$\times
10^7$ g cm$^{-3}$.

</DOC>
<DOC>
<DOCNO> 122078 </DOCNO>
Faint Quasar Surveys


  Faint quasar surveys are necessary complements to bright quasar surveys to
remove the degeneracy between redshift and luminosity inherent in any single
magnitude-limited sample. I discuss two ongoing surveys for faint quasars at
3.3<z<5 and 5<z<6 using imaging data from the Big Throughput Camera on the CTIO
4m. I also discuss a sample of faint spectroscopically selected AGN with z<4.7
found serendipitously in the CNOC2 Field Galaxy Redshift Survey. Faint quasars
at 2<z<3.5 from this sample, when combined with literature data on more
luminous quasars at the same redshift, show evidence for a much weaker Baldwin
Effect in CIV 1549 and Ly-alpha than previously seen at z<1.5. This may imply
that the slopes of the Baldwin Effect for these transitions evolve with
redshift, steepening with cosmic time. Finally I discuss the prospects for
extending faint quasar surveys to z~7 using near-IR followup of very red
objects in the Red-Sequence Cluster Survey.

</DOC>
<DOC>
<DOCNO> 99520 </DOCNO>
Stability Properties of the Riemann Ellipsoids


  We study the ellipticity and the ``Nekhoroshev stability'' (stability
properties for finite, but very long, time scales) of the Riemann ellipsoids.
We provide numerical evidence that the regions of ellipticity of the ellipsoids
of types II and III are larger than those found by Chandrasekhar in the 60's
and that all Riemann ellipsoids, except a finite number of codimension one
subfamilies, are Nekhoroshev--stable. We base our analysis on a Hamiltonian
formulation of the problem on a covering space, using recent results from
Hamiltonian perturbation theory.

</DOC>
<DOC>
<DOCNO> 100480 </DOCNO>
Existence and measure of ergodic leaves in Novikov's problem on the


  We show that ``ergodic regime'' appears for generic dispersion relations in
the semiclassical motion of electrons in a metal and we prove that, in the
fixed energy picture, the measure of the set of such directions is zero.

</DOC>
<DOC>
<DOCNO> 101794 </DOCNO>
Minimax Entropy and Maximum Likelihood. Complementarity of tasks,


  Concept of exponential family is generalized by simple and general
exponential form. Simple and general potential are introduced. Maximum Entropy
and Maximum Likelihood tasks are defined. ML task on the simple exponential
form and ME task on the simple potentials are proved to be complementary in
set-up and identical in solutions. ML task on the general exponential form and
ME task on the general potentials are weakly complementary, leading to the same
necessary conditions. A hypothesis about complementarity of ML and MiniMax
Entropy tasks and identity of their solutions, brought up by a special case
analytical as well as several numerical investigations, is suggested in this
case.
  MiniMax Ent can be viewed as a generalization of MaxEnt for parametric linear
inverse problems, and its complementarity with ML as yet another argument in
favor of Shannon's entropy criterion.

</DOC>
<DOC>
<DOCNO> 10463 </DOCNO>
Thermal conductivity of pure and Mg-doped CuGeO_3 in the incommensurate


  The thermal conductivity \kappa of Cu_1-xMg_xGeO_3 is measured in magnetic
fields up to 16 T. At the transition field H_c to the high-field incommensurate
(I) phase, \kappa abruptly decreases. While \kappa of the pure CuGeO_3 is
enhanced with the application of higher magnetic fields, an anomalous plateau
feature shows up in the \kappa(H) profile in the I phase of the Mg-doped
samples which includes antiferromagnetic ordering (I-AF phase). With the help
of specific heat data, taken supplementally for the identical samples, the
above features are well understood that phonons are strongly scattered by spin
solitons and that \kappa in the I phase is governed by their spatial
distribution. In particular, the plateau feature in the doped samples suggests
"freezing" of the solitons, in which antiferromagnetism must be playing an
essential role because this feature is absent at temperatures above T_N.

</DOC>
<DOC>
<DOCNO> 150975 </DOCNO>
String Theory and the Space-Time Uncertainty Principle


  The notion of a space-time uncertainty principle in string theory is
clarified and further developed. The motivation and the derivation of the
principle are first reviewed in a reasonably self-contained way. It is then
shown that the nonperturbative (Borel summed) high-energy and high-momentum
transfer behavior of string scattering is consistent with the space-time
uncertainty principle. It is also shown that, in consequence of the principle,
string theories in 10 dimensions generically exhibit a characteristic length
scale which is equal to the well-known 11 dimensional Planck length
$g_s^{1/3}\ell_s$ of M-theory as the scale at which stringy effects take over
the effects of classical supergravity, even without involving D-branes
directly. The meanings of the space-time uncertainty relation in connection
with D-branes and black holes are discussed and reinterpreted. Finally, we
present a novel interpretation of the Schild-gauge action for strings from a
viewpoint of noncommutative geometry, which conforms to the space-time
uncertainty relation by manifestly exhibiting a noncommutativity of quantized
string coordinates dominantly between space and time. We also discuss the
consistency of the space-time uncertainty relation with S and T dualities.

</DOC>
<DOC>
<DOCNO> 152251 </DOCNO>
A Self-Tuning Solution of the Cosmological Constant Problem


  We discuss the four-dimensional cosmological constant problem in a
five-dimensional setting. A scalar field coupled to the SM forms dynamically a
smooth brane with four-dimensional Poincare invariance, independently of SM
physics. In this respect, our solution may be regarded as a self-tuning
solution, free of any singularities and fine-tuning problems.

</DOC>
<DOC>
<DOCNO> 121444 </DOCNO>
Big Bang Nucleosynthesis and Related Observations


  The current status of big bang nucleosynthesis is summarized. Particular
attention is paid to recent observations of He4 and Li7 and their systematic
uncertainties. Be and B are also discussed in connection to recent Li7
observations and the primordial Li7 abundance.

</DOC>
<DOC>
<DOCNO> 80638 </DOCNO>
Perfect discretizations of differential operators


  We investigate an approach for the numerical solution of differential
equations which is based on the perfect discretization of actions. Such perfect
discretizations show up at the fixed points of renormalization group
transformations. This technique of integrating out the high momentum degrees of
freedom with a path integral has been mainly used in lattice field theory,
therefore our study of its application to PDE's explores new possibilities. We
calculate the perfect discretized Laplace operator for several non-trivial
boundary conditions analytically and numerically. Then we construct a
parametrization of the perfect Laplace operator and we show that with this
parametrization discretization errors -- or computation time -- can be reduced
dramatically compared to the standard discretization.

</DOC>
<DOC>
<DOCNO> 152648 </DOCNO>
Born-Infeld action and Supersymmetry (in spanish)


  In the thesis we analize different problems related to the supersymmetric
extension of the Dirac-Born-Infeld action. In chapter 2 we introduce the DBI
action and show how it appears in string theory, we discuss also it's
connection with Dp-branes. Chapter 3 is a self contained introduction to
supersymmetry, with emphasis on BPS states. In chapter 4 we construct the N=2
supersymmetric extension of the Born-Infeld-Higgs in three space-time
dimensions and discuss it's BPS states and Bogomol'nyi bounds. In chapter 5 we
construct the N=1 supersymmetric extension of the non-abelian Born-Infeld
theory in four space-time dimensions. Chapter 6 deals with the analisis of BPS
and non-BPS solutions of the Dirac-Born-Infeld action and their interpretation
in superstring theory. Chapter 7 is devoted to the conclusions. Three appendix
complete the work.

</DOC>
<DOC>
<DOCNO> 67701 </DOCNO>
The interplay between perturbative QCD and power corrections: the


  The summary of the results of our next-to-next-to-leading fits of Tevatron
experimental data for $xF_3$ structure function of the $\nu N$ deep-inelastic
scattering is given. The special attention is paid to the extraction of twist-4
contributions and demonstration of the interplay between these effects and
higher-order perturbative QCD corrections. The factorization and
renormalization scale uncertainties of the results obtained are analysed

</DOC>
<DOC>
<DOCNO> 67640 </DOCNO>
On the Resummed Hadronic Spectra of Inclusive B Decays


  In this paper we investigate the hadronic mass spectra of inclusive B decays.
Specifically, we study how an upper cut on the invariant mass spectrum, which
is necessary to extract V_{ub}, results in the breakdown of the standard
perturbative expansion due to the existence of large infrared logs. We first
show how the decay rate factorizes at the level of the double differential
distribution. Then, we present closed form expressions for the resummed cut
rate for the inclusive decays B -> X_s gamma and B -> X_u e nu at
next-to-leading order in the infrared logs. Using these results, we determine
the range of cuts for which resummation is necessary, as well as the range for
which the resummed expansion itself breaks down. We also use our results to
extract the leading and next to leading infrared log contribution to the two
loop differential rate. We find that for the phenomenologically interesting cut
values, there is only a small region where the calculation is under control.
Furthermore, the size of this region is sensitive to the parameter
\bar{\Lambda}. We discuss the viability of extracting V_{ub} from the hadronic
mass spectrum.

</DOC>
<DOC>
<DOCNO> 7845 </DOCNO>
Reply to A. Louis Comment


  Reply to A. Louis Comment: Fluid-solid phase-separation in hard-sphere
mixtures is unrelated to bond-percolation

</DOC>
<DOC>
<DOCNO> 11224 </DOCNO>
Microscopic dynamics of a phase transition: equilibrium vs


  We present for the first time to the nuclear physics community the
Hamiltonian Mean Field (HMF) model. The model can be solved analytically in the
canonical ensemble and shows a second-order phase transition in the
thermodynamic limit. Numerical microcanonical simulations show interesting
features in the out-of-equilibrium regime: in particular the model has a
negative specific heat. The potential relevance for nuclear multifragmentation
is discussed.

</DOC>
<DOC>
<DOCNO> 151615 </DOCNO>
Duality Between String Junctions and D-Branes on Del Pezzo Surfaces


  We revisit local mirror symmetry associated with del Pezzo surfaces in
Calabi-Yau threefolds in view of five-dimensional N=1 E_N theories compactified
on a circle. The mirror partner of singular Calabi-Yau with a shrinking del
Pezzo four-cycle is described as the affine 7-brane backgrounds probed by a
D3-brane. Evaluating the mirror map and the BPS central charge we relate
junction charges to RR charges of D-branes wrapped on del Pezzo surfaces. This
enables us to determine how the string junctions are mapped to D-branes on del
Pezzo surfaces.

</DOC>
<DOC>
<DOCNO> 99669 </DOCNO>
Riemann-Roch via deformation quantization, II


  We prove a Riemann-Roch formula for deformation quantization of complex
manifolds and its corollary, an index theorem for elliptic pairs conjectured by
Schapira and Schneiders.

</DOC>
<DOC>
<DOCNO> 71888 </DOCNO>
Recent Developments in Supersymmetric Dark Matter


  A brief review is given of some of the recent developments in the theoretical
analyses of supersymmetric dark matter. These include the effects of
uncertainties in the wimp velocity and wimp density and of the effects of
uncertainties in the quark densities of the proton. Also analyzed are the
effects of non-universalities in the gaugino sector and their effects on
determining the nature of cold dark matter, i.e., if the neutralino is bino
like, higgsino like, or wino like. The maximum and the minimum elastic
neutralino proton cross sections are discussed and a comparison of the direct
and the indirect detection arising from the capture and annihilation of
neutralinos in the core of the earth and the sun is given. Some of the other
recent developments are summarized.

</DOC>
<DOC>
<DOCNO> 120542 </DOCNO>
Properties of the Molecular Clouds in NGC 205


  The nearby dwarf elliptical galaxy NGC 205 offers a unique opportunity for
high resolution studies of the interstellar medium in an elliptical galaxy.
This paper investigates the distribution of molecular gas, molecular line
ratios, and the relationships between atomic gas, molecular gas, and dust in
NGC 205. The line ratios 12CO(2-1)/(1-0) and 12CO(1-0)/13CO(1-0) in one of the
molecular clouds in NGC 205 are consistent with the ratios found in other
elliptical galaxies and in Galactic giant molecular clouds; they suggest that
the CO in this cloud is probably subthermally excited. Atomic gas, molecular
gas, and dust are very closely associated on scales of 100 pc; the atomic gas
can be understood as photodissociated envelopes around the molecular clouds.
The atomic column densities in this galaxy are quite low (10^20 cm^-2) because
the interstellar UV field is relatively low. The total gas-to-dust column
density ratios are consistent with Galactic gas-to-dust ratios. In short, the
molecular gas in NGC 205 seems to have very similar properties to the familiar
molecular clouds in our own Galaxy, except for the low atomic column densities.

</DOC>
<DOC>
<DOCNO> 85657 </DOCNO>
Mining Energy from a Black Hole by Strings


  We discuss how cosmic strings can be used to mine energy from black holes. A
string attached to the black hole gives rise to an additional channel for the
energy release. It is demonstrated that when a string crosses the event
horizon, its transverse degrees of freedom are thermally excited and thermal
string perturbations propagate along the string to infinity. The internal
metric induced on the 2D worldsheet of the static string crossing the horizon
describes a 2D black hole. For this reason thermal radiation of string
excitations propagating along the string can be interpreted as Hawking
radiation of the 2D black hole. It is shown that the rate of energy emission
through the string channel is of the same order of magnitude as the bulk
radiation of the black hole. Thus, for N strings attached to the black hole the
efficiency of string channels is increased by factor N. We discuss restrictions
on N which exist because of the finite thickness of strings, the gravitational
backreaction and quantum fluctuations. Our conclusion is that the energy
emission rate by strings can be increased as compared to the standard emission
in the bulk by the factor 10^3 for GUT strings and up to the factor 10^{31} for
electroweak strings.

</DOC>
<DOC>
<DOCNO> 120204 </DOCNO>
The Formation of Stellar Clusters: Gaussian Initial Conditions II


  Using hydrodynamic simulations we investigate the time evolution and
fragmentation of regions within molecular clouds which have lost their
turbulent support leading to gravitational contraction. The initial density
distributions are described by random Gaussian fluctuations with varying slopes
x of the power spectrum P(k) ~ k^-x, covering the range from flat (x=0) to very
steep spectra (x=3). We consider molecular cloud volumes containing different
masses relative to the average Jeans mass M_J, from 1 M_J to 222 M_J. This
parameter study extends the detailed analysis of systems with initially P(k) ~
k^-2 and mass 222 M_J presented by Klessen & Burkert (2000). The dynamical
evolution of the simulated molecular cloud regions is insensitive to the slope
of the initial density fluctuation spectrum. The system evolves into a
complicated network of intersecting filaments and collapsing clumps leading to
the formation of a compact cluster of accreting and interacting embedded
protostellar cores. The cluster builds up as bound entity, but dissolves later
due to collisional effects. In all simulations, the mass spectrum of collapsed
cores is very broad, has approximately log-normal shape and peaks roughly at
the average Jeans mass. This supports the hypothesis that the average Jeans
mass is the main parameter determining the peak in the stellar spectrum, and
suggests that the interplay between self-gravity on the one side and thermal
and turbulent pressure on the other side is the dominant process that regulates
the formation of stellar clusters.

</DOC>
<DOC>
<DOCNO> 118919 </DOCNO>
Galactic Halo substructure in the Sloan Digital Sky Survey: the ancient


  Two studies have recently reported the discovery of pronounced Halo
substructure in the Sloan Digital Sky Survey (SDSS) commissioning data. Here we
show that this Halo substructure is almost in its entirety due to the expected
tidal stream torn off the Sagittarius dwarf galaxy during the course of its
many close encounters with the Milky Way. This interpretation makes strong
predictions on the kinematics and distances of these stream stars. Comparison
of the structure in old horizontal branch stars, detected by the SDSS team,
with the carbon star structure discovered in our own survey, indicates that
this halo stream is of comparable age to the Milky Way. It would appear that
the Milky Way and the Sagittarius dwarf galaxy have been a strongly interacting
system for most of their existence. Once complete, the SDSS will provide a
unique dataset with which to constrain the dynamical evolution of the
Sagittarius dwarf galaxy, it will also strongly constrain the mass distribution
of the outer Milky Way.

</DOC>
<DOC>
<DOCNO> 8176 </DOCNO>
Non-Fermi-Liquid Scaling in Ce(Ru_{0.5}Rh_{0.5})_2Si_2


  We study the temperature and field dependence of the magnetic and transport
properties of the non-Fermi-liquid compound Ce(Ru_{1-x}Rh_x)_2Si_2 at x=0.5.
For fields $\lesssim $0.1T the experimental results show signatures of the
presence of Kondo-disorder, expected to be large at this concentration. For
larger fields, however, magnetic and transport properties are controlled by the
coupling of the conduction electrons to critical spin-fluctuations. The
temperature dependence of the susceptibility as well as the scaling properties
of the magnetoresistance are in very good agreement with the predictions of
recent dynamical mean-field theories of Kondo alloys close to a spin-glass
quantum critical point.

</DOC>
<DOC>
<DOCNO> 11149 </DOCNO>
Off equilibrium magnetic properties in a model for vortices in


  We study the properties of a simple lattice model of repulsive particles
diffusing in a pinning landscape. The behaviour of the model is very similar to
the observed physics of vortices in superconductors. We compare and discuss the
equilibrium phase diagram, creep dynamics, the Bean state profiles, hysteresis
of magnetisation loops (including the second peak feature), and, in particular,
``off equilibrium'' relaxations. The model is analytically tractable in replica
mean field theory and numerically via Monte Carlo simulations. It offers a
comprehensive schematic framework of the observed phenomenology.

</DOC>
<DOC>
<DOCNO> 11433 </DOCNO>
Character Expansions, Itzykson-Zuber Integrals, and the QCD Partition


  A combinatorial formula to generate U(N) character expansions is presented.
It is shown that the resulting character expansion formulas greatly simplify a
number of problems where integrals over the group manifolds need to be
calculated. Several examples are given, including direct and very quick
calculations of the Itzykson-Zuber integral and the finite volume effective
partition function of QCD in the sector with a given topological charge.

</DOC>
<DOC>
<DOCNO> 123150 </DOCNO>
The X-ray emission of 3C 346 and its environment


  We present a detailed spectral and spatial analysis of the X-ray properties
of the compact and unusual radio galaxy 3C 346, combining information from
ROSAT and ASCA. The dominant component of X-ray emission (~ 10^44 ergs/s in
each of the 0.5-3 keV and 2-10 keV bands) is unresolved and not heavily
absorbed (intrinsic N_H ~< 2 10^21 cm^-2), with evidence for variability of 32
+/- 13% over 18 months. We relate the X-ray emission to radio structures on
both milliarcsecond scales and the arcsecond scales which Chandra can resolve.
The absence of X-ray absorption, and the radio/optical/X-ray colors, when
combined with previous radio evidence that the source is a foreshortened FRII,
suggest that the radio jets are seen at an angle to the line of sight of about
30 degrees, intermediate between the radio-galaxy and quasar classes. Roughly a
third of the soft X-ray emission is from a cluster atmosphere, for which we
measure a temperature of 1.9 (+1.3, -0.7) keV, making this the second
low-redshift (z < 0.2) powerful radio galaxy, after Cygnus A, with a measured
cluster temperature. At a jet angle of ~ 30 degrees, all the radio structures
lie within the core radius of the cluster, for which the cooling time is
sufficiently long that there is no reason to expect the presence of a cooling
flow. The radio lobes of 3C 346 are roughly in pressure balance with the
external medium under the assumptions that the energy densities in the magnetic
field and radiating particles balance and that a source of excess pressure in
the radio lobes, commonly invoked in other radio galaxies, is absent here.

</DOC>
<DOC>
<DOCNO> 121924 </DOCNO>
High resolution spectroscopy of H II Galaxies: Structure and Supersonic


  We present high resolution echelle spectroscopy of a sample of H II galaxies.
In all galaxies we identify different H(alpha) emitting knots along the slit
crossing the nucleus. All of these have been isolated and separately analyzed
through luminosity and size vs diagnosis plots. We find that in all cases, for
a particular galaxy, the bulk of emission comes from their main knot and
therefore, at least for the compact class galaxies we are dealing with,
luminosity and sigma values measured using single aperture observations would
provide similar results to what is obtained with spatially resolved
spectroscopy. In the size vs plots as expected there is a shift in the
correlations depending on whether we are including all emission in a single
point or we split it in its different emitting knots. The problem of a proper
determination of the size of the emitting region so that it can be used to
determine the mass of the system remains open. From the data set gathered,
using the highest surface brightness points as recently proposed by
Fuentes-Masip et al. (2000), the best luminosity vs correlation turns out to be
consistent with a Virial model.

</DOC>
<DOC>
<DOCNO> 40193 </DOCNO>
The First Results of K2K long-baseline Neutrino Oscillation Experiment


  The first results of the K2K(KEK to Kamioka) long-baseline neutrino
oscillation experiment are presented in this talk. In 1999 7.2x10^18 protons on
target were delivered to the experiment. During this period of running there
were 3 events fully contained in the Super-Kamiokande inner detector fiducial
area which occurred during the beam spill timing window. In the case of no
oscillations the expected number of events during this period was 12.3+1.7-1.9.
The near detectors located at KEK also have begun detailed measurements of
neutrino interactions in water at around 1 GeV.

</DOC>
<DOC>
<DOCNO> 116825 </DOCNO>
Measurements of RF Cavity Voltages by X-ray Spectrum Measurements


  Measurement of the endpoints of X-ray spectra emitted from RF cavities is a
useful non-invasive technique for measuring peak voltages within the cavities.
The matching of calculated X-ray spectra to measured spectra is described, with
emphasis upon the endpoint region.

</DOC>
<DOC>
<DOCNO> 119242 </DOCNO>
HST/STIS spectroscopy of the optical outflow from DG Tau: structure and


  We have carried out a spatio-kinematic study of the outflow from the
classical T Tauri star DG Tau using the Space Telescope Imaging Spectrograph
(STIS) on board the Hubble Space Telescope (HST). A series of seven spatially
offset long-slit spectra spaced by 0.07'' were obtained along the axis of the
outflow to build up a 3-D intensity-velocity ``cube'' in various forbidden
emission lines (FELs) and Ha. Here we present high spatial resolution synthetic
line images close to the star in distinct radial velocity intervals (from ~ +50
km/s to ~ -450 km/s in four bins, each ~ 125 km/s wide). The lowest velocity
emission is also examined in finer detail (from +60 km/s to -70 km/s in five
bins ~ 25 km/s wide). We have found that the highest velocity and most highly
collimated component, i.e. the jet, can be traced from DG Tau to a distance D ~
0.7''. The jet is on the axis of a pear-shaped limb-brightened bubble which
extends between 0.4'' and 1.5'' from the source and which we interpret as a bow
shock. Other condensations are seen close to the star indicating ongoing
temporal variations in the flow. The low-velocity component of the outflow is
found to be spatially wide close to the source (~ 0.2'' at D=0.2''), in
contrast to the high velocity jet (width <~ 0.1''). We have also found evidence
to suggest that the density increases longitudinally with proximity to the
source and also laterally towards the flow axis. Thus, at least in the case of
DG Tau, the flow becomes gradually denser as it increases in velocity and
becomes more collimated. Our observations show a continous bracketing of the
higher speed central flow within the lower speed, less collimated, broader
flow, down to the lowest velocity scales. This suggests that the low and high
velocity FELs in the highly active T Tauri star DG Tau are intimately related.

</DOC>
<DOC>
<DOCNO> 117486 </DOCNO>
Three-Layered Atmospheric Structure in Accretion Disks Around


  Modeling of the x-ray spectra of the Galactic superluminal jet sources GRS
1915+105 and GRO J1655-40 reveal a three-layered atmospheric structure in the
inner region of their accretion disks. Above the cold and optically thick disk
of a temperature 0.2-0.5 keV, there is a warm layer with a temperature of
1.0-1.5 keV and an optical depth around 10. Sometimes there is also a much
hotter, optically thin corona above the warm layer, with a temperature of 100
keV or higher and an optical depth around unity. The structural similarity
between the accretion disks and the solar atmosphere suggest that similar
physical processes may be operating in these different systems.

</DOC>
<DOC>
<DOCNO> 122362 </DOCNO>
Near-Infrared Integral Field Spectroscopy of Damped Lyman-alpha Systems


  We assess the feasibility of detecting star formation in damped Lyman-alpha
systems (DLAs) at z>1 through near-infrared spectroscopy using the forthcoming
integral field units on 8m-class telescopes. Although their relation to
galaxies is not well established, high-z DLAs contain most of the neutral gas
in the Universe, and this reservoir is depleted with time - presumably through
star formation. Line emission should be an indicator of star formation
activity, but searches based on Lyman-alpha are unreliable because of the
selective extinction of this resonant UV line. Using more robust lines such as
H-alpha forces a move to the near-infrared at z>1. For line emission searches,
spectroscopy is more sensitive than imaging, but previous long-slit
spectroscopic searches have been hampered by the likelihood that any star
forming region in the DLA galaxy disk would fall outside the narrow slit. The
new integral field units such as CIRPASS on Gemini will cover sufficient solid
angles to intercept these, even in the extreme case of large galactic disks at
high redshift. On an 8m-class telescope, star formation rates of <1M_sun/yr
will be reached at z~1.4 with H-alpha in the H-band. Such star formation rates
are well below L* for the high-z Lyman-break population, and are comparable
locally to the luminous giant HII complexes in M101. It appears that
instruments such as CIRPASS on Gemini will have both the sensitivity and the
survey area to measure star formation rates in z>1 DLAs. These observations
will probe the nature of damped Lyman-alpha systems and address their relation
to galaxies.

</DOC>
<DOC>
<DOCNO> 121440 </DOCNO>
Red Giants in ISOGAL: Tracers of the Evolution of the Galaxy


  The DENIS/ISOGAL near/mid-IR survey of the Milky Way for the first time
probes stellar populations in the innermost obscured regions of our galaxy.
Ages, metallicities and extinction-corrected luminosities are derived for these
stars individually by isochrone fitting to the preliminary IR photometry. A few
hundred AGB stars with thick circumstellar dust envelopes are identified. An
old metal-rich population dominates in the inner galactic Bulge, but there are
indications for the presence of a younger population. The inner Bulge has a
tri-axial shape, as traced by depth effects on the observed luminosity
distributions.

</DOC>
<DOC>
<DOCNO> 68528 </DOCNO>
The Higgs Mass and New Physics Scales in the Minimal Standard Model


  We study the theoretical correlation between the Higgs mass of the minimal
standard model and the scale at which new physics is expected to occur. In
addition to the classic constraints of unitarity, triviality and vacuum
stability, we reexamine the constraints imposed by the precision electroweak
data. We then pay particular attention to the constraint imposed by the absence
of fine-tuning in the Higgs mass parameter (the Veltman condition). We find
that the fine-tuning condition places a significant constraint on the new
physics scale for the Higgs mass range 100 GeV < m_h < 200 GeV mostly
unconstrained by the classic constraints.

</DOC>
<DOC>
<DOCNO> 70384 </DOCNO>
From Hadrons to Nuclei: Crossing the Border


  The study of nuclei predates by many years the theory of quantum
chromodynamics. More recently, effective field theories have been used in
nuclear physics to ``cross the border'' from QCD to a nuclear theory. We are
now entering the second decade of efforts to develop a perturbative theory of
nuclear interactions using effective field theory. This work describes the
current status of these efforts.

</DOC>
<DOC>
<DOCNO> 170368 </DOCNO>
A unified (classical-quantum-statistical) formalism for continuous


  A unified (classical-quantum-statistical) formalism for a system with
continuous spectrum is introduced. For this kind of systems ergodicity behavior
and the existence of microcanonical and canonical (KMS) equilibrium is proved.
It is argued that the continuous spectrum condition is essential for the
thermodynamical behavior

</DOC>
<DOC>
<DOCNO> 152600 </DOCNO>
Boundary String Field Theory of the DDbar System


  We develop the boundary string field theory approach to tachyon condensation
on the DDbar system. Particular attention is paid to the gauge fields, which
combine with the tachyons in a natural way. We derive the RR-couplings of the
system and express the result in terms of Quillen's superconnection. The result
is related to an index theorem, and is thus shown to be exact.

</DOC>
<DOC>
<DOCNO> 80893 </DOCNO>
Deconfining Phase Transition in 2+1 D: the Georgi-Glashow Model


  We analyze the finite temperature deconfining phase transition in 2+1
dimensional Georgi-Glashow model. We show explicitly that the transition is due
to the restoration of the magnetic $Z_2$ symmetry and that it is in the Ising
universality class. We find that neglecting effects of the charged $W$ bosons
leads to incorrect predictions for the value of the critical temperature and
the universality class of the transition, as well as for various correlation
functions in the high temperature phase. We derive the effective action for the
Polyakov loop in the high temperature phase and calculate the correlation
functions of magnetic vortex operators.

</DOC>
<DOC>
<DOCNO> 121071 </DOCNO>
Spectral Signatures of KiloHertz Quasi-Periodic Oscillations from


  Correlations discovered between millisecond timing properties and spectral
properties in neutron star x-ray binaries are described and then interpreted in
relation to accretion flows in the systems. Use of joint timing and spectral
observations to test for the existence of the marginally stable orbit, a key
prediction of strong field general relativity, is described and observations of
the neutron star x-ray binary 4U1820-303 which suggest that the signature of
the marginally stable orbit has been detected are presented.

</DOC>
<DOC>
<DOCNO> 40349 </DOCNO>
Lower limit on the mass of the neutralino (LSP) at LEP with the ALEPH


  The large amount of data accumulated at LEP2 by the ALEPH experiment has been
used to search for supersymmetric particles. No signal has been found therefore
limits have been determined. Within the Constrained Minimal Supersymmetric
Standard Model, the constraints from direct SUSY searches of charginos,
sleptons and neutralinos, are combined to extract a lower limit on the mass of
the neutralino considered to be the Lightest Supersymmetric particle. An
improved limit is obtained when the limit on the Higgs mass is included.
Neutralino masses up to 38 GeV/c^2 are excluded at 95 % confidence level.

</DOC>
<DOC>
<DOCNO> 8833 </DOCNO>
A minimal model for slow dynamics: Compaction of granular media under


  Based on experiments of the compaction of granular materials under periodic
shear of a packing of glass beads, a minimal model for the dynamics of the
packing density as a function of time is proposed. First, a random ``energy
landscape'' is created by a random walk (RW) in energy. Second, an ensemble of
RWs is performed for various temperatures in different temperature-time
sequences. We identify the minimum (mean) of the energy landscape with the
maximum (random) density. The temperature scaled by the step-size of the energy
landscape determines the dynamics of the system and can be regarded as the
agitation or shear amplitude. The model reproduces qualitatively both tapping
and shear experiments.
  {\bf Key-words}: Compaction, crystallization, Sinai-diffusion, random walks,
quenched disorder

</DOC>
<DOC>
<DOCNO> 117416 </DOCNO>
Hubble Space Telescope imaging and ground-based spectroscopy of old nova


  In this paper we report on the first five out of eleven observations in our
programme of Hubble Space Telescope (HST) imaging of old nova shells. We
present new WFPC2 images of the shells around FH Ser and V533 Her taken in the
F656N (Halpha+[NII]) filter. We also show long-slit spectra taken using the
William Herschel Telescope (WHT) in La Palma for these objects in the same
spectral range. The shell around FH Ser is found to be a prolate ellipsoid of
ellipticity 1.3 +/- 0.1 inclined at 62 +/- 4 deg to the line of sight. The
shell has an equatorial ring which is found to be due to increased emission in
the two [NII] lines rather than Halpha. The expansion velocity, systemic
velocity and distance are found to be 490 +/- 20 km/s, -45 km/s and 950 +/- 50
pc. The origin of the [NII] equatorial ring is discussed in the context of a
photoionization feature resulting from aspherical illumination by the central
source rather than a simple density enhancement. It is possible however that
the ring is also in part due to an extremely localised increase in the nitrogen
abundance. Similar imaging and spectroscopy of the nova V533 Her reveal a shell
of radius 5 +/- 0.7 arcsec with an axial ratio of 1.2 +/- 0.2, expansion
velocity of 850 +/- 150 km/s and distance 1250 +/- 300 pc. The shells around BT
Mon, DK Lac and V476 Cyg were not detected with HST.

</DOC>
<DOC>
<DOCNO> 122210 </DOCNO>
Resolving Sirius-like binaries with the Hubble Space Telescope


  We present initial results from a Hubble Space Telescope ultraviolet imaging
survey of stars known to have hot white-dwarf companions which are unresolved
from the ground. The hot companions, discovered through their EUV or UV
emission, are hidden by the overwhelming brightnesses of the primary stars at
visible wavelengths. Out of 17 targets observed, we have resolved eight of them
with the Wide Field Planetary Camera~2, using various ultraviolet filters. Most
of the implied orbital periods for the resolved systems are hundreds to
thousands of years, but in at least three cases (56 Persei, zeta Cygni, and
REJ1925-566) it shouldbe possible to detect the orbital motions within the next
few years, and they may eventually yield new dynamically determined masses for
the white-dwarf components. The 56 Persei and 14 Aurigae systems are found to
be quadruple and quintuple, respectively, including the known optical
components as well as the newly resolved white-dwarf companions. The mild
barium star zeta Cygni, known to have an 18 year spectroscopic period, is
marginally resolved. All of these new resolved Sirius-type binaries will be
useful in determining gravitational redshifts and masses of the white-dwarf
components.

</DOC>
<DOC>
<DOCNO> 116662 </DOCNO>
Improvements of the Discrete Dipole Approximation method


  The discrete-dipole approximation (DDA) is a flexible technique for computing
scattering and absorption by targets of arbitrary geometry. In this paper we
perform systematic study of various non-stationary iterative (conjugate
gradient) methods in search for the most efficient one in order to solve the
system of equations arising in DDA. We document implementation of these methods
in our public domain code DDSCAT.5a

</DOC>
<DOC>
<DOCNO> 151849 </DOCNO>
Supersymmetric Three-Form Flux Perturbations on $AdS_5$


  We consider warped type IIB supergravity solutions with three-form flux and
${\cal N}=1$ supersymmetry, which arise as the supergravity duals of confining
gauge theories. We first work in a perturbation expansion around $AdS_5 \times
S^5$, as in the work of Polchinski and Strassler, and from the ${\cal N}=1$
conditions and the Bianchi identities recover their first-order solution
generalized to an arbitrary ${\cal N}=1$ superpotential. We find the second
order dilaton and axion by the same means. We also find a simple family of
exact solutions, which can be obtained from solutions found by Becker and
Becker, and which includes the recent Klebanov--Strassler solution.

</DOC>
<DOC>
<DOCNO> 102256 </DOCNO>
Quantum-mechanical tunneling: differential operators, zeta-functions and


  We consider in detail the quantum-mechanical problem associated with the
motion of a one-dimensional particle under the action of the double-well
potential. Our main tool will be the euclidean (imaginary time) version of the
path-integral method. Once we perform the Wick rotation, the euclidean equation
of motion is the same as the usual one for the point particle in real time,
except that the potential at issue is turned upside down. In doing so, our
double-well potential becomes a two-humped potential. As required by the
semiclassical approximation we may study the quadratic fluctuations over the
instanton which represents in this context the localised finite-action
solutions of the euclidean equation of motion. The determinants of the
quadratic differential operators are evaluated by means of the zeta-function
method. We write in closed form the eigenfunctions as well as the energy
eigenvalues corresponding to such operators by using the shape-invariance
symmetry. The effect of the multi-instantons configurations is also included in
this approach.

</DOC>
<DOC>
<DOCNO> 101520 </DOCNO>
Recovering plane curves from their bitangents


  We show that a general plane curve of degree at least 4 is uniquely
determined by the full set of its bitangent lines. This problem has an
elementary solution for degree at least 5, and the paper is almost entirely
devoted to curves of degree 4, where we generalize the result to nodal
quartics. In other words, we show that a general curve of genus 3 can be
recovered from its 28 odd theta-characteristics.

</DOC>
<DOC>
<DOCNO> 169949 </DOCNO>
Bell's inequalities III. Logical loophole in their formulation


  In a remarkably insightful pair of papers recently, Sica demonstrated that:
dichotomic data taken in any experiment that violates Bell's inequalities
``cannot represent any data streams that could possibly exist or be imagined''
if it is to be consistent with the derivation of the inequalities.\cite{sica}
The present writer maintains, however, that corrections in the formulation of
Bell's analysis loosen restrictions imposed by Bell inequalities. Moreover, it
is argued that the resolution proposed by Sica for the conflict arising from
the fact that real data does violate Bell inequalities, namely that the
functional form of the correlations considered by Bell must be amended, is
untenable on physical grounds. Finally, an alternate resolution is proposed.

</DOC>
<DOC>
<DOCNO> 70289 </DOCNO>
Baryon mass spectra with QCD- type screened potential


  The work is devoted to the description of baryon mass spectrum in the
quasy-relativistic quark potential model. For cosidering 3 - quark system
advantageous is the use of hyperspherical functions. For obtaining the mass -
seguence of $\Delta_{33}-$isobar the numerical computations were carryed out
with the use of screened QCD - motivated potential, the use of which gives
quite acceptable results even in the nonrelativistic approximation.

</DOC>
<DOC>
<DOCNO> 122859 </DOCNO>
Nucleosynthesis Calculations for the Ejecta of Neutron Star Coalescences


  We present the results of fully dynamical r-process network calculations for
the ejecta of neutron star mergers (NSMs). The late stages of the inspiral and
the final violent coalescence of a neutron star binary have been calculated in
detail using a 3D hydrodynamics code (Newtonian gravity plus backreaction
forces emerging from the emission of gravitational waves) and a realistic
nuclear equation of state. The found trajectories for the ejecta serve as input
for dynamical r-process calculations where all relevant nuclear reactions
(including beta-decays depositing nuclear energy in the expanding material) are
followed. We find that all the ejected material undergoes r-process. For an
initial Ye close to 0.1 the abundance distributions reproduce very accurately
the solar r-process pattern for nuclei with A above 130. For lighter nuclei
strongly underabundant (as compared to solar) distributions are encountered. We
show that this behaviour is consistent with the latest observations of very
old, metal-poor stars, despite simplistic arguments that have recently been
raised against the possibility of NSM as possible sources of Galactic r-process
material.

</DOC>
<DOC>
<DOCNO> 84858 </DOCNO>
Magnetic Field Evolution of Accreting Neutron Stars IV - Effect of the


  The evolution of the magnetic field in an accreting neutron star is
investigated using a fully general relativistic treatment and assuming that
initially the currents supporting the field are completely confined to the
crust. We find that the field decay slows down due to the inclusion of the
curvature of space-time but the final results do not differ significantly from
those obtained assuming a flat space-time. We also find that such modifications
are small compared to the uncertainties introduced by a lack of precise
knowledge of the neutron star micro-physics.

</DOC>
<DOC>
<DOCNO> 7722 </DOCNO>
Enhanced vortex damping by eddy currents in superconductor-semiconduc


  An enhancement of vortex-motion damping in thin Pb/In superconducting films
is obtained through coupling to an adjacent two-dimensional electron gas formed
in a modulation-doped GaAs/AlGaAs heterostructure. This effect is observed by
monitoring the power dissipation at the superconductor in the vortex state
while increasing the density of the electron gas using a gate voltage.
Quantitative agreement is found with calculations based on a viscous model of
vortex damping which considers generation of eddy currents in the electron gas
by moving flux lines. In the regime of filamentary and channel vortex flow,
eddy-current damping leads to striking dissipation breakdown due to stopping of
entire vortex channels.

</DOC>
<DOC>
<DOCNO> 120079 </DOCNO>
The Origin of the X-ray and Ultraviolet Emission in NGC 7469


  We present a spectral analysis of a 30d, near-continuous observation of the
Seyfert 1 galaxy NGC 7469 with RXTE. Daily integrations show strong spectral
changes during the observation. Ourmain result is that we find the X-ray
spectral index to be correlated with the UV flux. Furthermore, the broad-band
X-ray photon flux is also correlated with the UV continuum. These correlations
point towards a model in which the X-rays originate via thermal Comptonization
of UV seed photons. Furthermore, the UV is also correlated with the
extrapolation of the X-ray power law into the soft X-ray/EUV region. Our data
analysis therefore re-opens the possibility the the UV photons and their
variability arise from reprocessing, as long as the primary source of heating
is photo-electric absorption in the reprocessor, rather than Compton
downscattering, A coherent picture of the X-ray/UV variability can therefore be
constructed whereby absorption and reprocessing of EUV/soft X-rays in a
standard accretion disk produce a variable seed photon distribution which are
in turn up-scattered into the X-ray band. We also find a significant
correlation between the 2-10 keV flux and the 6.4 keV iron K-line suggesting
that at least some portion of the line originates within ~1 lt day of the X-ray
continuum source. Neither the power law photon index nor the Compton reflection
component are correlated with the 2-10 keV flux. The latter is not correlated
with the iron K line flux either. We do find an apparent correlation between
the X-ray spectral index and the strength of the Compton reflection component.
In an Appendix we show, however, that this can be produced by a combination of
statistical and systematic errors. We conclude the apparent variations in the
Compton reflection component may be an artifact of these effects.

</DOC>
<DOC>
<DOCNO> 102693 </DOCNO>
Resonance Theory for Schroedinger Operators


  Resonances which result from perturbation of embedded eigenvalues are studied
by time dependent methods. A general theory is developed, with new and weaker
conditions, allowing for perturbations of threshold eigenvalues and relaxed
Fermi Golden rule. The exponential decay rate of resonances is addressed; its
uniqueness in the time dependent picture is shown is certain cases. The
relation to the existence of meromorphic continuation of the properly weighted
Green's function to time dependent resonance is further elucidated, by giving
an equivalent time dependent asymptotic expansion of the solutions of the
Schr\"odinger equation. \keywords{Resonances; Time-dependent Schr\"odinger
equation}

</DOC>
<DOC>
<DOCNO> 84342 </DOCNO>
Canonical formulation of N = 2 supergravity in terms of the Ashtekar


  We reconstruct the Ashtekar's canonical formulation of N = 2 supergravity
(SUGRA) starting from the N = 2 chiral Lagrangian derived by closely following
the method employed in the usual SUGRA. In order to get the full graded algebra
of the Gauss, U(1) gauge and right-handed supersymmetry (SUSY) constraints, we
extend the internal, global O(2) invariance to local one by introducing a
cosmological constant to the chiral Lagrangian. The resultant Lagrangian does
not contain any auxiliary fields in contrast with the 2-form SUGRA and the SUSY
transformation parameters are not constrained at all. We derive the canonical
formulation of the N = 2 theory in such a manner as the relation with the usual
SUGRA be explicit at least in classical level, and show that the algebra of the
Gauss, U(1) gauge and right-handed SUSY constraints form the graded algebra,
G^2SU(2)(Osp(2,2)). Furthermore, we introduce the graded variables associated
with the G^2SU(2)(Osp(2,2)) algebra and we rewrite the canonical constraints in
a simple form in terms of these variables. We quantize the theory in the
graded-connection representation and discuss the solutions of quantum
constraints.

</DOC>
<DOC>
<DOCNO> 116423 </DOCNO>
The Laser-Driven Vacuum Photodiode


  A vacuum photodiode driven by a pulsed laser can sustain an average current
very similar to that of a continous diode, where the latter is described by
Child's law.

</DOC>
<DOC>
<DOCNO> 10403 </DOCNO>
Josephson Plasma Mode in Fields Parallel to Layers of


  Josephson plasma resonance measurements under magnetic fields parallel to the
CuO_2 layers as functions of magnetic field, temperature, and microwave
frequency have been performed in Bi_2Sr_2CaCu_2O_{8+\delta} single crystals
with doping range being from optimal to under-doped side. The feature of the
resonance is quite unique and cannot be explained by the conventional
understandings of the Josephson plasma for H \parallel c, that requires a new
theory including coupling effect between Josephson vortex lattice and Josephson
plasma.

</DOC>
<DOC>
<DOCNO> 120570 </DOCNO>
Dilaton-derived quintessence scenario leading naturally to the late-time


  Quintessence scenarios provide a simple explanation for the observed
acceleration of the Universe. Yet, explaining why acceleration did not start a
long time ago remains a challenge. The idea that the transition from radiation
to matter domination played a dynamical role in triggering acceleration has
been put forward in various guises. We propose a simple dilaton-derived
quintessence model in which temporary vacuum domination is naturally triggered
by the radiation to matter transition. In this model Einstein's gravity is
preserved but quintessence couples non-minimally to the cold dark matter, but
not to ``visible'' matter. Such couplings have been attributed to the dilaton
in the low-energy limit of string theory beyond tree level. We also show how a
cosmological constant in the string frame translates into a quintessence-type
of potential in the atomic frame.

</DOC>
<DOC>
<DOCNO> 152263 </DOCNO>
Generalised twisted partition functions


  We consider the set of partition functions that result from the insertion of
twist operators compatible with conformal invariance in a given 2D Conformal
Field Theory (CFT). A consistency equation, which gives a classification of
twists, is written and solved in particular cases. This generalises old results
on twisted torus boundary conditions, gives a physical interpretation of
Ocneanu's algebraic construction, and might offer a new route to the study of
properties of CFT.

</DOC>
<DOC>
<DOCNO> 84907 </DOCNO>
Scattering of Dirac Waves off Kerr Black Holes


  Chandrasekhar separated the Dirac equation for spinning and massive particles
in Kerr geometry into radial and angular parts. Here we solve the complete wave
equation and find out how the Dirac wave scatters off Kerr black holes. The
eigenfunctions, eigenvalues and reflection and transmission co-efficients are
computed. We compare the solutions with several parameters to show how a
spinning black hole distinguishes mass and energy of incoming waves. Very close
to the horizon the solutions become independent of the particle parameters
indicating an universality of the behaviour.

</DOC>
<DOC>
<DOCNO> 67790 </DOCNO>
The QCD pomeron at TESLA - motivation and exclusive J/psi production


  We briefly present the motivation for studying the processes mediated by the
QCD pomeron at high energy e+e- colliders. We describe the behaviour of the
cross-section for the reaction gamma gamma to J/psi J/psi obtained from the
BFKL equation with dominant non-leading corrections. We give the predictions
for the rates of anti-tagged e+e- to e+e- J/psi J/psi events in TESLA and
conclude that such reactions may be excellent probes of the hard pomeron.

</DOC>
<DOC>
<DOCNO> 102680 </DOCNO>
Quantum lattice models at intermediate temperatures


  We analyze the free energy and construct the Gibbs-KMS states for a class of
quantum lattice systems, at low temperatures and when the interactions are
almost diagonal in a suitable basis. We study systems with continuous symmetry,
but our results are valid for discrete symmetry breaking only. Such phase
transitions occur at intermediate temperatures where the continuous symmetry is
not broken, while at very low temperature continuous symmetry breaking may
occur.

</DOC>
<DOC>
<DOCNO> 69499 </DOCNO>
Charmless two body hadronic decays of $\Lambda_b$ baryon


  Using a theoretical framework based on the next-to-leading order QCD improved
effective Hamiltonian, we have estimated the branching ratios and asymmetry
parameters for the two body charmless nonleptonic decay modes of $\Lambda_b$
baryon i.e. $\Lambda_b \to p (\pi/\rho),~p(K/K^*)$ and $\Lambda (\pi/\rho)$,
within the framework of generalized factorization. The nonfactorizable
contributions are parametrized in terms of the effective number of colors,
$N_c^{eff}$. So in addition to the naive factorization approach ($N_c^{eff}=3
$), here we have taken two more values for $N_c^{eff}$ i.e., $N_c^{eff}=2 $ and
$\infty $. The baryonic form factors at maximum momentum transfer ($ q_m^2 $)
are evaluated using the nonrelativistic quark model and the extrapolation of
the form factors from $q_m^2$ to the required $q^2$ value is done by assuming
the pole dominance. The obtained branching ratios for $\Lambda_b \to p\pi, ~pK$
processes lie within the present experimental upper limit .

</DOC>
<DOC>
<DOCNO> 8908 </DOCNO>
Electrodynamics of quasi-two-dimensional BEDT-TTF charge transfer salts


  We consider the millimeter-wave electrodynamics specific to
quasi-two-dimensional conductors and superconductors based on the organic donor
molecule BEDT-TTF. Using realistic physical parameters, we examine the current
polarizations that result for different oscillating (GHz) electric and magnetic
field polarizations. We show that, in general, it is possible to discriminate
between effects (dissipation and dispersion) due to in-plane and interlayer ac
currents. However, we also show that it is not possible to selectively probe
any single component of the in-plane conductivity tensor, and that excitation
of interlayer currents is strongly influenced by the sample geometry and the
electromagnetic field polarization.

</DOC>
<DOC>
<DOCNO> 102086 </DOCNO>
Hamiltonian stationary Lagrangian surfaces in Hermitian symmetric spaces


  This paper is the third of a series on Hamiltonian stationary Lagrangian
surfaces. We present here the most general theory, valid for any Hermitian
symmetric target space. Using well-chosen moving frame formalism, we show that
the equations are equivalent to an integrable system, generalizing the C^2
subcase analyzed in the first article (arXiv:math.DG/0009202). This system
shares many features with the harmonic map equation of surfaces into symmetric
spaces, allowing us to develop a theory close to Dorfmeister, Pedit and Wu's,
including for instance a Weierstrass-type representation. Notice that this
article encompasses the article mentioned above, although much fewer details
will be given on that particular flat case.

</DOC>
<DOC>
<DOCNO> 118615 </DOCNO>
Prospects for observing pulsating red giants with the MONS Star Trackers


  K and M giants show variability on timescales from years down to days and
possibly even hours. I discuss the contribution that can be made with
high-precision photometry that will be obtained by the MONS Star Trackers.
These include observations of flare-like events on Mira variables, and
oscillation spectra for K giants and short-period M giants.

</DOC>
<DOC>
<DOCNO> 80672 </DOCNO>
Numerical analysis of fractional charge solutions on the torus


  We study by numerical methods a particular kind of SU(N) Yang-Mills solutions
of the Euclidean equations of motion which appear on the torus when twisted
boundary conditions are imposed. These are instanton-like configurations with
the peculiarity of having fractional topological charge. We focus on those
solutions with minimal non-trivial action $S=8\pi^2/\N$ and extract their
properties in a few different cases, paying special attention to the $N \to
\infty$ limit.

</DOC>
<DOC>
<DOCNO> 68821 </DOCNO>
A Dynamical Solution to the Problem of a Small Cosmological Constant and


  Increasing evidence suggests that most of the energy density of the universe
consists of a dark energy component with negative pressure, a ``cosmological
constant" that causes the cosmic expansion to accelerate. In this paper, we
address the puzzle of why this component comes to dominate the universe only
recently rather than at some much earlier epoch. We present a class of theories
based on an evolving scalar field where the explanation is based entirely on
internal dynamical properties of the solutions. In the theories we consider,
the dynamics causes the scalar field to lock automatically into a negative
pressure state at the onset of matter-domination such that the present epoch is
the earliest possible time, consistent with nucleosynthesis restrictions, when
it can start to dominate.

</DOC>
<DOC>
<DOCNO> 83126 </DOCNO>
cc-Golog: Towards More Realistic Logic-Based Robot Controllers


  High-level robot controllers in realistic domains typically deal with
processes which operate concurrently, change the world continuously, and where
the execution of actions is event-driven as in ``charge the batteries as soon
as the voltage level is low''. While non-logic-based robot control languages
are well suited to express such scenarios, they fare poorly when it comes to
projecting, in a conspicuous way, how the world evolves when actions are
executed. On the other hand, a logic-based control language like \congolog,
based on the situation calculus, is well-suited for the latter. However, it has
problems expressing event-driven behavior. In this paper, we show how these
problems can be overcome by first extending the situation calculus to support
continuous change and event-driven behavior and then presenting \ccgolog, a
variant of \congolog which is based on the extended situation calculus. One
benefit of \ccgolog is that it narrows the gap in expressiveness compared to
non-logic-based control languages while preserving a semantically well-founded
projection mechanism.

</DOC>
<DOC>
<DOCNO> 119290 </DOCNO>
Limits on the accretion rates onto massive black holes in nearby


  The radio emission from supermassive black holes in nearby early-type
galaxies can be used to test possible explanations for their low luminosities.
We calculate the expected contribution from thermal synchrotron emission from
hot accretion flows to the high radio frequency observations of NGC 2300, NGC
1399, NGC 4278 and NGC 4594. We find that, in all cases, and in accordance with
our previous findings, hot flows accreting close to their Bondi rates
overestimate significantly the observed fluxes. This implies that simply
assuming a low radiative efficiency for the accreting gas is not enough to
explain their low luminosities. Smaller central densities and accretion rates,
as expected in the presence of strong mass loss or convection in the flows, can
help reconcile the models with observations. We also show that a significant
contribution to the high-frequency radio spectra can be due to non-thermal
synchrotron emission from the small scale radio jets observed in these systems,
allowing for even lower accretion rates in the inflows. We suggest that these
outflows or jets may dump significant energy into the surronding medium close
to the accretion radius and so reduce the accretion rates onto these systems.
We discuss the relationship between the radio flux and black hole mass for the
observed sample and its potential importance for probing accretion models.

</DOC>
<DOC>
<DOCNO> 121305 </DOCNO>
The Chandra High Energy Transmission Grating Observation of an X-ray


  We present a preliminary analysis of the first high-resolution X-ray spectrum
of a Seyfert 2 galaxy, Mkn 3, obtained with the High Energy Transmission
Grating Spectrometer onboard the Chandra X-ray Observatory. The high-energy
spectrum (lambda < 4 Ang) is dominated by reflection of the AGN continuum
radiation in a cold optically thick medium and contains bright K-alpha
fluorescent lines from iron and silicon, as well as weak, blended lines from
sulfur and magnesium. The soft X-ray emission (4 < lambda < 23 Ang) is
spatially extended along the [O III] ionization cone and shows discrete
signatures of emission following recombination and photoexcitation produced in
a warm photoionized region. The measured iron L line fluxes indicate that
emission from collisionally ionized plasma is almost completely negligible, and
does not contribute significantly to the total energy budget of the X-ray
emission. We find that significant fractions of the H- and He-like resonance
lines, as well as the observed iron L lines are produced through re-emission
from the warm absorbing medium observed in Seyfert 1 galaxies. Its X-ray
spectral properties are qualitatively consistent with those of a typical
Seyfert 1 galaxy viewed at a different orientation, and provide further
convincing evidence for the existence of an obscured Seyfert 1 nucleus in Mkn
3.

</DOC>
<DOC>
<DOCNO> 10964 </DOCNO>
Time of avalanche mixing of granular materials in a half filled rotated


  The avalanche mixing of granular solids in a slowly rotated 2D upright drum
is studied. We demonstrate that the account of the difference $\delta$ between
the angle of marginal stability and the angle of repose of the granular
material leads to a restricted value of the mixing time $\tau$ for a half
filled drum. The process of mixing is described by a linear discrete difference
equation. We show that the mixing looks like linear diffusion of fractions with
the diffusion coefficient vanishing when $\delta$ is an integer part of $\pi$.
Introduction of fluctuations of $\delta$ supresses the singularities of
$\tau(\delta)$ and smoothes the dependence $\tau(\delta)$.

</DOC>
<DOC>
<DOCNO> 100566 </DOCNO>
Problems on the geometry of finitely generated solvable groups


  A survey of problems, conjectures, and theorems about quasi-isometric
classification and rigidity for finitely generated solvable groups.

</DOC>
<DOC>
<DOCNO> 9215 </DOCNO>
Transport properties and structures of vortex matter in layered


  In this paper we analyze the structure, phase transitions and some transport
properties of the vortex system when the external magnetic field lies parallel
to the planes in layered superconductors. We show that experimental results for
resistivity are qualitatively consistent with numerical simulations that
describe the melting of a commensurate rotated lattice. However for some
magnetic fields, the structure factor indicates the occurrence of smectic peaks
at an intermediate temperature regime.

</DOC>
<DOC>
<DOCNO> 116832 </DOCNO>
RBF neural net based classifier for the AIRIX accelerator fault


  The AIRIX facility is a high current linear accelerator (2-3.5kA) used for
flash-radiography at the CEA of Moronvilliers France. The general background of
this study is the diagnosis and the predictive maintenance of AIRIX. We will
present a tool for fault diagnosis and monitoring based on pattern recognition
using artificial neural network. Parameters extracted from the signals recorded
on each shot are used to define a vector to be classified. The principal
component analysis permits us to select the most pertinent information and
reduce the redundancy. A three layer Radial Basis Function (RBF) neural network
is used to classify the states of the accelerator. We initialize the network by
applying an unsupervised fuzzy technique to the training base. This allows us
to determine the number of clusters and real classes, which define the number
of cells on the hidden and output layers of the network. The weights between
the hidden and the output layers, realising the non-convex union of the
clusters, are determined by a least square method. Membership and ambiguity
rejection enable the network to learn unknown failures, and to monitor
accelerator operations to predict future failures. We will present the first
results obtained on the injector.

</DOC>
<DOC>
<DOCNO> 122865 </DOCNO>
Sunyaev-Zel'dovich Effect Imaging of Massive Clusters of Galaxies at


  We present Sunyaev-Zel'dovich Effect (SZE) imaging observations of three
distant (z > 0.8) and highly X-ray luminous clusters of galaxies, Cl1226+33,
Cl0152-13 and MS1054-03. Two of the clusters, Cl1226+33 and Cl0152-13, were
recently discovered in deep ROSAT x-ray images. Their high X-ray luminosity
suggests that they are massive systems which, if confirmed, would provide
strong constraints on the cosmological parameters of structure formation
models. Our Sunyaev-Zel'dovich Effect data provide confirmation that they are
massive clusters similar to the well studied cluster MS1054-03. Assuming the
clusters have the same gas mass fraction as that derived from SZE measurements
of eighteen known massive clusters, we are able to infer their mass and
electron temperature from the SZE data. The derived electron temperatures are
9.8, 8.7, and 10.4 keV, respectively, and we infer total masses of ~2 x 10^14
h^-1 Msun within a radius of 65 arcsec (340 h^{-1} kpc) for all three clusters.
For Cl0152-13 and MS1054-03 we find good agreement between our SZE derived
temperatures and those inferred from X-ray spectroscopy. No X-ray derived
temperatures are available for Cl1226+33, and thus the SZE data provide the
first confirmation that it is indeed a massive system. The demonstrated ability
to determine cluster temperatures and masses from SZE observations without
access to X-ray data illustrates the power of using deep SZE surveys to probe
the distant universe.

</DOC>
<DOC>
<DOCNO> 122177 </DOCNO>
Simultaneous BeppoSAX and RXTE observations of the X-ray burst sources


  We have obtained spectral and timing data on GX 3+1 and Ser X-1. Both sources
were observed simultaneously with BeppoSAX and RXTE. The RXTE data is used to
provide power spectra and colour-colour diagrams in order to constrain the
state (and thus track $\dot M$) the sources are in. The BeppoSAX data provide
the broad-band spectra. The spectra of both sources are reasonably well-fit
using a model consisting of a disk-blackbody, a comptonized component and a Fe
line, absorbed by interstellar absorption. The electron temperature (kT$_{\rm
e}$) of the Comptonizing plasma is in both cases $\sim$2.5 keV. This implies
that no strong high-energy tail from the Comptonized component is present in
either of the sources. We discuss the similarities between these burst sources
and the luminous X-ray sources located in globular clusters. We find that the
spectral parameters of the comptonized component provide information about the
mass-accretion rate, which agrees well with estimates from the timing and
spectral variations.

</DOC>
<DOC>
<DOCNO> 151723 </DOCNO>
Extended (Super-) KP-hierarchies and generalised String equations


  We propose a consistently algebraic formulation of the extended KP
(supersymmetric) integrable -hierarchy systems. We exploit the results already
established in [14] and which consist in a framework suspected to unify in a
fascinating way all the possible supersymmetric KP-hierarchies and then their
underlying supergravity theories . This construction leads among other to built
explicit non standard integrable Lax evolution equations suspected to reduce to
the well known KP integrable equation. We present also a contribution of our
construction to the subject of string equation and solitons. Other algebraic
properties are also presented

</DOC>
<DOC>
<DOCNO> 118383 </DOCNO>
Stellar Populations in the Large Magellanic Cloud from 2MASS


  We present a morphological analysis of the feature-rich 2MASS LMC
color-magnitude diagram, identifying Galactic and LMC populations and
estimating the density of LMC populations alone. We also present the projected
spatial distributions of various stellar populations. Major populations are
identified based on matching morphological features of the CMD with expected
positions of known populations, isochrone fits, and analysis of the projected
spatial distributions. The LMC populations along the first-ascent RGB and AGB
are quantified. We find the RGB tip at $K_s=12.3\pm0.1$. Preliminary isochrone
analysis is done for giant populations in the bar and the outer regions of the
Cloud. We find no significant differences in metallicities and ages between the
fields. The observed LMC giant branch is well-fit by published tracks in the
CIT/CTIO system with a distance modulus of $\mu=18.5\pm0.1$, reddening
$E_{B-V}=0.15-0.20$, metallicity $Z=0.004^{+0.002}_{-0.001}$ and age 3-13 Gyr.
Analysis of deep 2MASS engineering data with six times the standard exposure
produces similar estimates.

</DOC>
<DOC>
<DOCNO> 119716 </DOCNO>
The MACHO Project LMC Variable Star Inventory. IX. Frequency Analysis of


  More than 1300 variables classified provisionally as first overtone RR Lyrae
pulsators in the MACHO variable star database of the Large Magellanic Cloud
(LMC) have been subjected to standard frequency analysis. Based on the remnant
power in the prewhitened spectra, we found 70% of the total population to be
monoperiodic. The remaining 30% (411 stars) are classified as one of 9 types
according to their frequency spectra. Several types of RR Lyrae pulsational
behavior are clearly identified here for the first time. Together with the
earlier discovered double-mode (fundamental & first overtone) variables this
study increased the number of the known double-mode stars in the LMC to 181.
During the total 6.5yr time span of the data, 10% of the stars show strong
period changes. We also discovered two additional types of multifrequency
pulsators with low occurrence rates of 2% for each. In the first type there
remains one closely spaced component after prewhitening by the main pulsation
frequency. In the second type the number of remnant components is two, they are
also closely spaced, and, in addition, they are symmetric in their frequency
spacing relative to the central component. This latter type of variables is
associated with their relatives among the fundamental pulsators, known as
Blazhko variables. Their high frequency (~20%) among the fundamental mode
variables versus the low occurrence rate of their first overtone counterparts
makes it more difficult to explain Blazhko phenomenon by any theory depending
mainly on the role of aspect angle or magnetic field. Current theoretical
models invoke nonradial pulsation components in these stars.

</DOC>
<DOC>
<DOCNO> 101902 </DOCNO>
From Random Polynomials to Symplectic Geometry


  We review some recent results on random polynomials and their generalizations
in complex and symplectic geometry. The main theme is the universality of
statistics of zeros and critical points of (generalized) polynomials of degree
$N$ on length scales of order $\frac{D}{\sqrt{N}}$ (complex case), resp.
$\frac{D}{N}$ (real case).

</DOC>
<DOC>
<DOCNO> 122270 </DOCNO>
A Mosaic of the Coma Cluster of Galaxies with XMM-Newton


  The Coma cluster of galaxies was observed with XMM-Newton in 12 partially
overlapping pointings. We present here the resulting X-ray map in different
energy bands and discuss the large scale structure of this cluster. Many point
sources were found throughout the observed area, at least 11 of them are
coincident with bright galaxies. We also give a hardness ratio map at the so
far highest angular resolution obtained for a cluster of galaxies. In this map
we found soft regions at the position of bright galaxies, little variation in
the central 15 arcmin, but some harder regions north of the line NGC 4874 - NGC
4889.

</DOC>
<DOC>
<DOCNO> 100487 </DOCNO>
Rigidity property of diagram groups


  We show a rigid connection between two classical objects: the R.Thompson
group F and the Dunce hat. A diagram group of a directed 2-complex contains a
copy of F if and only if the complex contains a copy of the Dunce hat.

</DOC>
<DOC>
<DOCNO> 71243 </DOCNO>
Kinematic Effects in Radiative Quarkonia Decays


  Non-relativistic QCD (NRQCD) predicts colour octet contributions to be
significant not only in many production processes of heavy quarkonia but also
in their radiative decays. We investigate the photon energy distributions in
these processes in the endpoint region. There the velocity expansion of NRQCD
breaks down which requires a resummation of an infinite class of colour octet
operators to so-called shape functions. We model these non-perturbative
functions by the emission of a soft gluon cluster in the initial state. We
found that the spectrum in the endpoint region is poorly understood if the
values for the colour octet matrix elements are taken as large as indicated
from NRQCD scaling rules. Therefore the endpoint region should not be taken
into account for a fit of the strong coupling constant at the scale of the
heavy quark mass.

</DOC>
<DOC>
<DOCNO> 40022 </DOCNO>
P Pbar to T Tbar H: A Discovery mode for the Higgs boson at the Tevatron


  The production of a Standard Model Higgs boson in association with a top
quark pair at the upcoming high luminosity run (15 inverse fb integrated
luminosity) of the Fermilab Tevatron (root s = 2.0 TeV) is revisited. For Higgs
masses below 140 GeV we demonstrate that the production cross section times
branching ratio for H->B Bbar decays yields a significant number of events and
that this mode is competitive with and complementary to the searches using P
Pbar -> WH, ZH associated production. For higher mass Higgs bosons the H -> W+
W- decays are more difficult but have the potential to provide a few
spectacular events.

</DOC>
<DOC>
<DOCNO> 40115 </DOCNO>
Study of chi_{c1} and chi_{c2} meson production in B meson decays


  Using a sample of 9.7 million B meson pairs collected with the CLEO detector,
we study inclusive B meson decays to the chi_c1 and chi_c2 charmonia states. We
measure the branching fraction for the inclusive chi_c1 production in B decays
to be Br(B->chi_c1 X)=(4.14+-0.31+-0.40)*10^-3, where the first uncertainty is
statistical and the second one is systematic. We obtain the branching fractions
for direct chi_c1 and chi_c2 production in B decays by subtracting the
contribution from the decay chain B->psi(2S)X with psi(2S)->chi_c1,2 gamma. We
measure Br(B->chi_c1[direct] X)=(3.83+-0.31+-0.40)*10^-3. No statistically
significant signal for chi_c2 production is observed in either case. We
determine the 95% C.L. upper limits to be Br(B->chi_c2 X)<2.0*10^-3,
Br(B->chi_c2[direct] X)<1.7*10^-3, and Br(B->chi_c2[direct]
X)/Br(B->chi_c1[direct] X)<0.44. All quoted results are preliminary.

</DOC>
<DOC>
<DOCNO> 99657 </DOCNO>
A focus on focal surfaces


  We make a systematic study of the focal surface of a congruence of lines in
the projective space. Using differential techniques together with techniques
from intersection theory, we reobtain in particular all the invariants of the
focal surface (degree, class, class of its hyperplane section, sectional genus
and degrees of the nodal and cuspidal curve). We study in particular the
congruences of chords to a smooth curve and the congruences of bitangents or
flexes to a smooth surface. We find that they possess unexpected components in
their focal surface, and conjecture that they are the only ones with this
property.

</DOC>
<DOC>
<DOCNO> 102475 </DOCNO>
Mordell-Weil lattices in characteristic 2, III: A Mordell-Weil lattice


  In the first paper of this series, we constructed a family of lattices in
dimensions 2^{n+1} for positive integers n, and proved that the associated
lattice packings of spheres equal or exceed the previous records for several
values of n. In this paper we analyze the case n=6, which is now the first case
where the resulting lattice MW128 yields a previously unknown lattice of record
density. We prove that the elliptic curve used to construct this lattice has
trivial Tate-Shafarevich group, and exhibit on that curve a rational point
whose canonical height attains our lower bound on the minimal norm of MW128. We
thus obtain the normalized center density of the lattice. We then report on a
computation that determined all the rational points of minimal norm, thus
obtaining the kissing number of MW128. Like the packing density, the kissing
number of MW128 is by a considerable factor the largest known kissing number of
a lattice in this dimension.

</DOC>
<DOC>
<DOCNO> 13152 </DOCNO>
The direct link model for polymer rings as a topological field theory


  Polymer rings in solution are either permanently entangled or not. Permanent
topological restrictions give rise to additional entropic interactions apart
from the ones arising due to mere chain flexibility or excluded volume.
Conversely, entangled polymer rings systems may be formed by closing randomly
entangled flexible linear chains. The dependance of linking numbers between
randomly entangled rings on the chain length, more specifically the second
topological moment $<n^2>$, i.e. the average squared linking number, may be
determined. In this paper, an approach recently discussed in mathematical
physics and called abelian BF theory, is presented which allows to express the
linking constraint in its simplest form, the Gauss integral, in terms of two
gauge fields. The model of Brereton and Shah for a single ring entangled with
many other surrounding rings is rederived. The latter model is finally used to
calculate the second topological moment, in agreement with a recent result by
Ferrari, Kleinert, and Lazzizzera obtained by using ${\rm n}$-component
$\phi^4$ theory in the limit ${\rm n}\to 0$.

</DOC>
<DOC>
<DOCNO> 119245 </DOCNO>
Galactic Bulge Microlensing Events with Clump Giants as Sources


  We present preliminary results of the analysis of 5 years of MACHO data on
the Galactic bulge microlensing events with clump giants as sources. In
particular, we discuss: 1) the selection of `giant' events, 2) distribution of
impact parameters, 3) distribution of event durations, 4) the concentration of
long duration events in MACHO field 104 centered on (l,b) = (3.1,-3.0). We
report the preliminary average optical depth of (2.0 +/- 0.4) x 10^{-6}
(internal) at (l,b) = (3.9,-3.8). We discuss future work and prospects for
building a coherent model of the Galaxy.

</DOC>
<DOC>
<DOCNO> 102340 </DOCNO>
The Generalized Method of Exhaustion


  The method of exhaustion is generalized to a simple formula that can be used
to integrate functions under very general conditions, provided that the
integral exists. Both a geometric proof (following the usual procedure for the
method of exhaustion) and an independent algebraic proof are provided.
Applications provided as examples include use of the formula to generate new
series for common functions as well as computing the group velocity
distribution resulting from waves diffracted from an aperture.

</DOC>
<DOC>
<DOCNO> 39998 </DOCNO>
KLOE first results on hadronic physics


  The KLOE detector at DAFNE, the Frascati Phi-factory, has collected about 8
millions phi decays in 1999. Measurements of Phi decays into pi0, eta, eta',
f0(980), a0(980) and pi+pi-pi0 have been performed with statistical accuracy
better than previously in a single detector, as well as new decay modes. Phi
radiative decays can clarify the nature of f0 and a0 (are they 4 quark states?)
and measure the eta-eta' mixing angle. Analysis of Phi->pi+pi-pi0 allows us to
extract the possible existence of direct decay in addition to the dominant
rho-pi mode and to obtain a precise measurement of the rho parameters such as
the mass difference between the charged and neutral rho, previously never seen.

</DOC>
<DOC>
<DOCNO> 9888 </DOCNO>
Bayesian Reconstruction of Approximately Periodic Potentials at Finite


  The paper discusses the reconstruction of potentials for quantum systems at
finite temperatures from observational data. A nonparametric approach is
developed, based on the framework of Bayesian statistics, to solve such inverse
problems. Besides the specific model of quantum statistics giving the
probability of observational data, a Bayesian approach is essentially based on
"a priori" information available for the potential. Different possibilities to
implement "a priori" information are discussed in detail, including
hyperparameters, hyperfields, and non--Gaussian auxiliary fields. Special
emphasis is put on the reconstruction of potentials with approximate
periodicity. The feasibility of the approach is demonstrated for a numerical
model.

</DOC>
<DOC>
<DOCNO> 70314 </DOCNO>
Probing Neutral Gauge Boson Self-interactions in ZZ Production at Hadron


  A detailed analysis of ZZ production at the upgraded Fermilab Tevatron and
the CERN Large Hadron Collider is presented for general ZZZ and ZZ\gamma
couplings. Deviations from the Standard Model gauge theory structure for each
of these can be parameterized in terms of two form factors which are severely
restricted by unitarity at high energy. Achievable limits on these couplings
are shown to be a dramatic improvement over the limits currently obtained by
e^+e^- experiments.

</DOC>
<DOC>
<DOCNO> 14012 </DOCNO>
Resonant-Cavity-Induced Phase Locking and Voltage Steps in a Josephson


  We describe a simple dynamical model for an underdamped Josephson junction
array coupled to a resonant cavity. From numerical solutions of the model in
one dimension, we find that (i) current-voltage characteristics of the array
have self-induced resonant steps (SIRS), (ii) at fixed disorder and coupling
strength, the array locks into a coherent, periodic state above a critical
number of active Josephson junctions, and (iii) when $N_a$ active junctions are
synchronized on an SIRS, the energy emitted into the resonant cavity is
quadratic with $N_a$. All three features are in agreement with a recent
experiment [Barbara {\it et al}, Phys. Rev. Lett. {\bf 82}, 1963 (1999)]}.

</DOC>
<DOC>
<DOCNO> 67766 </DOCNO>
Singlet parton evolution at small x: a theoretical update


  This is an extended and pedagogically oriented version of our recent work, in
which we proposed an improvement of the splitting functions at small x which
overcomes the apparent problems encountered by the BFKL approach.

</DOC>
<DOC>
<DOCNO> 121735 </DOCNO>
On the streaming motions of haloes and galaxies


  A simple model of how objects of different masses stream towards each other
as they cluster gravitationally is described. The model shows how the mean
streaming velocity of dark matter particles is related to the motions of the
parent dark matter haloes. It also provides a reasonably accurate description
of how the pairwise velocity dispersion of dark matter particles differs from
that of the parent haloes. The analysis is then extended to describe the
streaming motions of galaxies. This shows explicitly that the streaming motions
measured in a given galaxy sample depend on how the sample was selected, and
shows how to account for this dependence on sample selection. In addition,we
show that the pairwise dispersion should also depend on sample type. Our model
predicts that, on small scales, redshift space distortions should affect red
galaxies more strongly than blue.

</DOC>
<DOC>
<DOCNO> 102623 </DOCNO>
Explicit elements of norm one for cyclic groups


  Let G be a cyclic p-group of order p^n acting by automorphisms on a
(non-necessarily commutative) ring R. Suppose there is an element x in R such
that (1 + t + ... + t^{p-1})(x) = 1, where t is an element of order p in G. We
show how to construct an element y in R such that (1 + s + ... + s^{p^n-1})(y)
= 1, where s is a generator of G.

</DOC>
<DOC>
<DOCNO> 69520 </DOCNO>
Mott dissociation of D-mesons at the chiral phase transition and


  We investigate the in-medium modification of the charmonium breakup processes
due to the Mott-effect for D-mesons at the chiral phase transition. A model
calculation for the process J/Psi+pi --> D+D^*+ h.c. is presented which
demonstrates that threshold effects in the thermal averaged breakup cross
section can be explained as a Mott transition where final state quark-antiquark
bound states enter the continuum of resonant states at the QCD phase
transition. Applications to heavy-ion collisions within a modified Glauber
model scenario and the phenomenon of anomalous J/$\psi$ suppression in the CERN
NA50 experiment are addressed.

</DOC>
<DOC>
<DOCNO> 11264 </DOCNO>
The Principle of Valence Bond Amplitude Maximization in Cuprates: How it


  A simple microscopic principle of `Valence bond (nearest neighbor singlet)
amplitude maximization '(VBAM) is shown to be present in undoped and optimally
doped cuprates and unify the very different orderings such as
antiferromagnetism in the Mott insulator and the robust superconductivity
accompanied by an enhanced charge and stripe correlations in the optimally
doped cuprates. VBAM is nearly synonymous with the energy minimization
principle. It is implicit in the RVB theory and thereby makes the predictions
of RVB mean field theory of superconductivity qualitatively correct.

</DOC>
<DOC>
<DOCNO> 170269 </DOCNO>
Relativistic Aharonov-Casher Phase in Spin One


  The Aharonov-Casher (AC) phase is calculated in relativistic wave equations
of spin one. The AC phase has previously been calculated from the Dirac-Pauli
equation using a gauge-like technique \cite{MK1,MK2}. In the spin-one case, we
use Kemmer theory (a Dirac-like particle theory) to calculate the phase in a
similar manner. However the vector formalism, the Proca theory, is more widely
known and used. In the presence of an electromagnetic field, the two theories
are `equivalent' and may be transformed into one another. We adapt these
transformations to show that the Kemmer theory results apply to the Proca
theory. Then we calculate the Aharonov-Casher phase for spin-one particles
directly in the Proca formalism.

</DOC>
<DOC>
<DOCNO> 179014 </DOCNO>
Photoproduction of $\eta$-mesons off light nuclei


  Photoproduction of $\eta$-mesons off deuteron is studied within the
Alt-Grassberger-Sandhas formalism for different parameters of $\eta N$
interaction. The calculations revealed peaks in the energy dependence of the
total cross-section.

</DOC>
<DOC>
<DOCNO> 121536 </DOCNO>
Searching for Tidal Tails in Galactic Dwarf Spheroidal Satellites


  We present preliminary results of a long-term project to investigate the
process of accretion and tidal disruption of dSph satellites in the Galactic
halo and, in particular, to search for new tidal tails in a sample of nearby
dSph satellites of the Milky Way. Here we present our finding of extra-tidal
debris in the Ursa Minor dS ph and discuss the detection by the Sloan Digitized
Sky Survey team of what could be a tidal stream associated to the Sagittarius
dSph.

</DOC>
<DOC>
<DOCNO> 151940 </DOCNO>
First results for the Coulomb gauge integrals using NDIM


  The Coulomb gauge has at least two advantadges over other gauge choices in
that bound states between quarks and studies of confinement are easier to
understand in this gauge. However, perturbative calculations, namely Feynman
loop integrations are not well-defined (there are the so-called energy
integrals) even within the context of dimensional regularization. Leibbrandt
and Williams proposed a possible cure to such a problem by splitting the
space-time dimension into $D=\omega+\rho$, i.e., introducing a specific one
parameter $\rho$ to regulate the energy integrals. The aim of our work is to
apply negative dimensional integration method (NDIM) to the Coulomb gauge
integrals using the recipe of split-dimension parameters and present complete
results -- finite and divergent parts -- to the one and two-loop level for
arbitrary exponents of propagators and dimension.

</DOC>
<DOC>
<DOCNO> 116486 </DOCNO>
Signal Selection Based on Stochastic Resonance


  Noise aids the encoding of continuous signals into pulse sequences by way of
stochastic resonance and endows the encoding device with a preferred frequency.
We study encoding by a threshold device based on the Ornstein-Uhlenbeck
process, equivalent to the leaky integrate-and-fire neuron model. Preferred
frequency, optimum noise intensity, and optimum signal-to-noise ratio are shown
to be linearly related to the AC amplitude of the input signal. The DC
component of the input tunes the device either into transmission (preferred
frequency nearly independent of signal amplitude) or selection mode (frequency
rising with amplitude). We argue that this behavior may facilitate selective
signal processing in neurons.

</DOC>
<DOC>
<DOCNO> 84795 </DOCNO>
Generating Conjecture and Some Einstein-Maxwell Field of High Symmetry


  For stationary cylindrically symmetric solutions of the Einstein-Maxwell
equation we have shown that the "charged" solutions of McCrea, Chitre et
al.(CGN), Van den Bergh and Wils (VW) can be obtained from the seed metrics
using generating conjecture. The McCrea "charged" solution has as a seed vacuum
metric the Van Stockum solution with a Killing vector (0,0,1,0). The CGN
"charged" solution and the VW "charged" solution have the static seed metrics
connected by the complex substitution (t --> iz), (z --> it) and the Killing
vector which is a simple linear combination of ${\partial}_{\phi}$ and
${\partial}_{t}$ Killing vectors (VW), respectively ${\partial}_{\phi}$ and
${\partial}_{z}$ Killing vectors (CGN).

</DOC>
<DOC>
<DOCNO> 9973 </DOCNO>
Finite-frequency optical absorption in 1D conductors and Mott-Hubbard


  The frequency-dependent conductivity is studied for the one-dimensional
Hubbard model, using a selection rule, the Bethe ansatz, and symmetries
associated with conservation laws. For densities where the system is metallic
the absorption spectrum has two contributions, a Drude peak at $\omega = 0$
separated by a pseudogap from a broad absorption band whose lower edge is
characterized by a non-classical critical exponent. Our findings shed new light
on the ``far infrared puzzle'' and other optical properties of metallic organic
chain compounds.

</DOC>
<DOC>
<DOCNO> 11777 </DOCNO>
Bond-disordered Anderson model on a two dimensional square lattice -


  Bond-disordered Anderson model in two dimensions on a square lattice is
studied numerically near the band center by calculating density of states
(DoS), multifractal properties of eigenstates and the localization length. DoS
divergence at the band center is studied and compared with Gade's result [Nucl.
Phys. B 398, 499 (1993)] and the powerlaw. Although Gade's form describes
accurately DoS of finite size systems near the band-center, it fails to
describe the calculated part of DoS of the infinite system, and a new
expression is proposed. Study of the level spacing distributions reveals that
the state closest to the band center and the next one have different level
spacing distribution than the pairs of states away from the band center.
Multifractal properties of finite systems furthermore show that scaling of
eigenstates changes discontinuously near the band center. This unusual behavior
suggests the existence of a new divergent length scale, whose existence is
explained as the finite size manifestation of the band center critical point of
the infinite system, and the critical exponent of the correlation length is
calculated by a finite size scaling. Furthermore, study of scaling of Lyapunov
exponents of transfer matrices of long stripes indicates that for a long stripe
of any width there is an energy region around band center within which the
Lyapunov exponents cannot be described by one-parameter scaling. This region,
however, vanishes in the limit of the infinite square lattice when
one-parameter scaling is restored, and the scaling exponent calculated, in
agreement with the result of the finite size scaling analysis.

</DOC>
<DOC>
<DOCNO> 68461 </DOCNO>
Neutrino Oscillations: Some theoretical ideas


  Talk given at Orbis Scientiae Conference, Coral Gables, FLA, Dec. 16-19,
1999. Talk surveys some recent three-neutrino models of neutrino masses and
mixings.

</DOC>
<DOC>
<DOCNO> 8498 </DOCNO>
Boundary-induced phase transitions in traffic flow


  Boundary-induced phase transitions are one of the surprising phenomena
appearing in nonequilibrium systems. These transitions have been found in
driven systems, especially the asymmetric simple exclusion process. However, so
far no direct observations of this phenomenon in real systems exists. Here we
present evidence for the appearance of such a nonequilibrium phase transition
in traffic flow occurring on highways in the vicinity of on- and off-ramps.
Measurements on a German motorway close to Cologne show a first-order
nonequilibrium phase transition between a free-flow phase and a congested
phase. It is induced by the interplay of density waves (caused by an on-ramp)
and a shock wave moving on the motorway. The full phase diagram, including the
effect of off-ramps, is explored using computer simulations and suggests means
to optimize the capacity of a traffic network.

</DOC>
<DOC>
<DOCNO> 70418 </DOCNO>
Neutrino Factories: Physics


  The recent evidence for neutrino oscillations opens a new and exciting era in
neutrino physics. The next generation of accelerator based neutrino oscillation
experiments are expected to confirm the nature of the oscillations, and begin
to measure some of the associated oscillation parameters. However, these
experiments will not be able to completely determine the mixing matrix,
determine the pattern of neutrino masses, or search for CP violation in the
lepton sector. Therefore we are motivated to consider the neutrino beams that
will be needed beyond the next generation of experiments. With this in mind the
physics case for a neutrino factory is discussed. It is shown that this new
type of neutrino source would enable the crucial questions to be addressed, and
perhaps provide enough information to discriminate between Grand Unified
Theories, or lead us to an alternative theoretical framework. It is possible
that measurements at a neutrino factory will point the way towards an
understanding of the origin of quark and lepton flavors.

</DOC>
<DOC>
<DOCNO> 71615 </DOCNO>
Upper bound on the scale of Majorana-neutrino mass generation


  We derive a model-independent upper bound on the scale of Majorana-neutrino
mass generation. The upper bound is $4\pi v^2/\sqrt 3 m_\nu$, where $v \simeq
246$ GeV is the weak scale and $m_\nu$ is the Majorana neutrino mass. For
neutrino masses implied by neutrino oscillation experiments, all but one of
these bounds are less than the Planck scale, and they are all within a few
orders of magnitude of the grand-unification scale.

</DOC>
<DOC>
<DOCNO> 102495 </DOCNO>
Asymptotic K-theory for groups acting on $\tildeA_2$ buildings


  Let $\Gamma$ be a torsion free lattice in $G=\PGL(3,{{\mathbb F}})$ where
${{\mathbb F}}$ is a nonarchimedean local field. Then $\Gamma$ acts freely on
the affine Bruhat-Tits building ${\mathcal B}$ of $G$ and there is an induced
action on the boundary $\Omega$ of ${\mathcal B}$. The crossed product
$C^*$-algebra ${\mathcal A}(\Gamma)=C(\Omega) \rtimes \Gamma$ depends only on
$\Gamma$ and is classified by its K-theory. This article shows how to compute
the K-theory of ${\mathcal A}(\Gamma)$ and of the larger class of rank two
Cuntz-Krieger algebras.

</DOC>
<DOC>
<DOCNO> 39831 </DOCNO>
Heavy Quark Decays


  The status of heavy-quark decays as of summer 1999 is reviewed. New
measurements of semileptonic B decays from LEP and from CLEO are reported and
the status of determining the CKM parameters |Vcb| and |Vub| is assessed. Rare
charmless hadronic B decays are reviewed, including the first observation of
B->pi pi from CLEO. First attempts to measure CP asymmetries in rare decays are
described. The implications of all of the data for our understanding of the
Standard Model are briefly assessed.

</DOC>
<DOC>
<DOCNO> 40425 </DOCNO>
Observation of the phi to eta' gamma decay with four charged particles


  Using 11.6 1/pb of data collected in the energy range 0.864-1.06 GeV by CMD-2
at VEPP-2M, the rare decay mode phi to eta' gamma was observed via the decay
chain eta' to pi+pi- eta, eta to pi+pi-pi0 or eta to pi+pi- gamma. The
following branching ratio was obtained: Br(phi to eta' gamma) =
(4.9^{+2.2}_{-1.8} +- 0.6) \cdot 10^{-5}.

</DOC>
<DOC>
<DOCNO> 85219 </DOCNO>
The Field Nature of Time in General Relativity


  The paper is devoted to the description of the reparametrization - invariant
dynamics of general relativity obtained by resolving constraints and
constructing equivalent unconstrained systems. The constraint-shell action
reveals the "field nature" of the geometric time in general relativity. The
time measured by the watch of an observer coincides with one of field
variables, but not with the reparametrization-noninvariant coordinate evolution
parameter.
  We give new solution of such problem, as the derivation of the path integral
representation of the causal Green functions in the Hamiltonian scheme of
general relativity.

</DOC>
<DOC>
<DOCNO> 119809 </DOCNO>
Power Density Spectra of Gamma-Ray Burst Light Curves: Implications on


  We study the power density spectrum (PDS) of artificial light curves of
observed gamma-ray bursts (GRBs). We investigate statistical properties of GRB
light curves by comparing the reported characteristics in the PDSs of the
observed GRBs with those that we model, and discuss implications on
interpretations of the PDS analysis results. Results of PDS analysis of
observed GRBs suggest that the averaged PDS of GRBs follows a power law over
about two decades of frequency with the power law index, -5/3, and the
distribution of individual power follows an exponential distribution. Though an
attempt to identify the most sensitive physical parameter has been made on the
basis of the internal shock model, we demonstrate that conclusions of this kind
of approach should be derived with due care. It is indicative that the physical
information extracted from the slope can be misleading. We show that the
reported slope and the distribution can be reproduced by adjusting the sampling
interval in the time domain for a given decaying timescale of individual pulse
in a specific form of GRB light curves. In particular, given that the temporal
feature is modeled by a two-sided exponential function, the power law behavior
with the index of -5/3 and the exponential distribution of the observed PDS is
recovered at the 64 ms trigger time scale when the decaying timescale of
individual pulse is $\sim 1$ second, provided that the pulse sharply rises.
Another way of using the PDS analysis is an application of the same method to
individual long bursts in order to examine a possible evolution of the decaying
timescale in a single burst.

</DOC>
<DOC>
<DOCNO> 70422 </DOCNO>
Higgs Transverse Momentum at the LHC


  Resummed QCD corrections to the transverse momentum ($Q_T$) distribution of
the Standard Model Higgs boson, produced at the CERN Large Hadron Collider, are
presented. The small $Q_T$ factorization formalism is reviewed, which is used
to extend the standard hadronic factorization theorem to the low $Q_T$ region,
with emphasis on the matching to the standard hadronic factorization.
Comparison of the $Q_T$ predictions from the extended factorization and the
parton shower method is performed.

</DOC>
<DOC>
<DOCNO> 170485 </DOCNO>
Bell's Theorem Without Hidden Variables


  Experiments motivated by Bell's theorem have led some physicists to conclude
that quantum theory is nonlocal. However, the theoretical basis for such claims
is usually taken to be Bell's Theorem, which shows only that if certain
predictions of quantum theory are correct, and a strong hidden-variable
assumption is valid, then a certain locality condition must fail. This locality
condition expresses the idea that what an experimenter freely chooses to
measure in one spacetime region can have no effect of any kind in a second
region situated spacelike relative to the first. The experimental results
conform closely to the predictions of quantum theory in such cases, but the
most reasonable conclusion to draw is not that locality fails, but rather that
the hidden-variable assumption is false. For this assumption conflicts with the
quantum precept that unperformed experiments have no outcomes. The present
paper deduces the failure of this locality condition directly from the precepts
of quantum theory themselves, in a way that generates no inconsistency or any
conflict with the predictions of relativistic quantum field theory.

</DOC>
<DOC>
<DOCNO> 151182 </DOCNO>
The Rotating Detector and Vacuum Fluctuations


  In this work we compare the quantization of a massless scalar field in an
inertial frame with the quantization in a rotating frame. We used the
Trocheries-Takeno mapping to relate measurements in the inertial and the
rotating frames. An exact solution of the Klein-Gordon equation in the rotating
coordinate system is found and the Bogolubov transformation between the
inertial and rotating modes is calculated, showing that the rotating observer
defines a vacuum state different from the Minkowski one. We also obtain the
response function of an Unruh-De Witt detector coupled with the scalar field
travelling in a uniformly rotating world-line. The response function is
obtained for two different situations: when the quantum field is prepared in
the usual Minkowski vacuum state and when it is prepared in the
Trocheries-Takeno vacuum state. We also consider the case of an inertial
detector interacting with the field in the rotating vacuum.

</DOC>
<DOC>
<DOCNO> 151943 </DOCNO>
Polarization of the Massless Fermionic Vacuum in the Background of a


  Effects of the configuration of an external static magnetic field in the form
of a singular vortex on the vacuum of a quantized massless spinor field are
determined. The most general boundary conditions at the punctured singular
point which make the twodimensional Dirac Hamiltonian to be self-adjoint are
employed.

</DOC>
<DOC>
<DOCNO> 119210 </DOCNO>
A Uniform Analysis of the Ly-alpha forest at z = 0 - 5: II. Measuring


  A homogeneous sample of 99 moderate resolution QSO spectra at z > 1.7 were
presented in Paper I, including 39 previously unpublished spectra from the
Multiple Mirror Telescope. The statistics of the Lyman alpha forest were
discussed. In this analysis, we demonstrate that a proximity effect is present
in the data, ie. there exists a significant (5.5$\sigma$) deficit of lines at
$z_{abs} \approx z_{em}$. Within 1.5 $h^{-1}$ Mpc of the QSO emission redshift,
the significance does depend on QSO luminosity, in accordance with the theory
that this effect is caused by enhanced ionization of hydrogen in the vicinity
of the QSO from UV photons from the QSO itself. The photoionization model of
Bajtlik, Duncan, and Ostriker (1988) permits an estimate of the mean intensity
of the extragalactic background radiation at the Lyman limit. We compare the
results of this standard analysis with those obtained using a maximum
likelihood technique. The best fit value for $J(\nu_{0})$ is
7.0$^{+3.4}_{-4.4}$ x 10$^{-22}$ ergs/s/cm$^{2}$/Hz/sr, over the redshift range
1.7 < z < 3.8, using QSO redshifts based on narrow emission lines. The best fit
value for the HI ionization rate is 1.9$^{+1.2}_{-1.0}$ x 10$^{-12}$ s$^{-1}$,
in good agreement with models of the background which incorporate QSOs only.
This large absorption line sample and these techniques for measuring the
background and understanding the systematics involved allow us to place what we
believe are are the firmest limits on the background at these redshifts.

</DOC>
<DOC>
<DOCNO> 120697 </DOCNO>
Baryonic Dark Matter in Galaxies


  Cosmological nucleosynthesis calculations imply that many of the baryons in
the Universe must be dark. We discuss the likelihood that some of these dark
baryons may reside in the discs or halos of galaxies. If they were in the form
of compact objects, they would then be natural MACHO candidates, in which case
they are likely to be the remnants of a first generation of pregalactic or
protogalactic Population III stars. Various candidates have been proposed for
such remnants - brown dwarfs, red dwarfs, white dwarfs, neutron stars or black
holes - and we review the many types of observations (including microlensing
searches) which can be used to constrain or exclude them.

</DOC>
<DOC>
<DOCNO> 100197 </DOCNO>
Spectral Radii of Bounded Operators on Topological Vector Spaces


  In this paper we develop a version of spectral theory for bounded linear
operators on topological vector spaces. We show that the Gelfand formula for
spectral radius and Neumann series can still be naturally interpreted for
operators on topological vector spaces. Of course, the resulting theory has
many similarities to the conventional spectral theory of bounded operators on
Banach spaces, though there are several important differences. The main
difference is that an operator on a topological vector space has several
spectra and several spectral radii, which fit a well-organized pattern.

</DOC>
<DOC>
<DOCNO> 150704 </DOCNO>
Confining Strings in the Abelian-Projected SU(3)-Gluodynamics


  String representation of the Wilson loop in 3D Abelian-projected
SU(3)-gluodynamics is constructed in the approximation that Abelian-projected
monopoles form a gas. Such an assumption is much weaker than the standard one,
demanding the monopole condensation. It is demonstrated that the summation over
world sheets, bounded by the contour of the Wilson loop, is realized by the
summation over branches of a certain effective multivalued potential of the
monopole densities. Finally, by virtue of the so-constructed representation of
the Wilson loop in terms of the monopole densities, this quantity is evaluated
in the approximation of a dilute monopole gas, which makes confinement in the
model under study manifest.

</DOC>
<DOC>
<DOCNO> 117760 </DOCNO>
Dusty Tori of Seyfert Nuclei


  Dusty tori around active galactic nuclei (AGNs) play an important role in the
classification of Seyfert galaxies. Therefore, physical properties of dusty
tori are of great interest. We briefly introduce three statistical studies
investigating properties of dusty tori; 1) physical sizes of dusty tori based
on water-vapor maser emission, 2) ionization condition of the inner wall of
tori based on high-ionization emission lines, and 3) viewing angle toward dusty
tori based on mid-infrared color.

</DOC>
<DOC>
<DOCNO> 119581 </DOCNO>
The X-ray spectra of Compton-thick Seyfert 2 galaxies as seen by


  Results from BeppoSAX observations of Compton--thick Seyfert 2 galaxies are
summarized and reviewed, and their general properties derived and discussed. In
five out of the seven observed sources, the nucleus is directly visible at high
X-ray energies, where the photons penetrate absorbers with column densities in
the range 1.1-4.3x10^{24} cm-2 (in the other two sources, NGC 1068 and NGC
7674, the nucleus is instead totally obscured at all energies, implying even
larger column densities). In most sources there is unambiguous evidence of a
reflection component from optically thick, cold matter, while in two (or maybe
four) cases there is also evidence of reflection from ionized matter. For the
sources with a measured X-ray luminosity, a comparison with the infrared
luminosity is made; while in two cases (the Circinus galaxy and NGC 4945) the
IR emission appears to be dominated by starburst activity, in the other three
sources (NGC 6240, Mrk 3 and TOL 0109-383) it is likely to be dominated by
reprocessing of the UV and X-ray photons emitted by an AGN.

</DOC>
<DOC>
<DOCNO> 71007 </DOCNO>
High Energy Neutrinos from Gamma-Ray Bursts


  Observations suggest that gamma-ray bursts (GRBs) are produced by the
dissipation of the kinetic energy of a relativistic fireball. In this talk,
recent work on the production of high energy neutrinos by GRB fireballs is
reviewed. A significant fraction of GRB energy is expected to be converted to
an accompanying burst of high energy neutrinos. Photomeson interactions produce
a burst of ~100 TeV neutrinos in coincidence with the GRB, and a burst of
\~10^18 eV neutrinos following the GRB on a time scale of 10 s. Inelastic p-n
nuclear collisions result in the production of a burst of ~10 GeV neutrinos in
coincidence with the GRB. Planned 1 km^3 neutrino telescopes are expected to
detect tens of 100 TeV neutrino events, and several 10^18 eV events, correlated
with GRBs per year. A suitably densely spaced detector may allow the detection
of several 10 GeV events per year. The detection of high-energy neutrino events
correlated with GRBs will allow to constrain GRB progenitor models and to test
the suggestion that GRBs accelerate protons to >10^20 eV. Moreover, such
detection will allow to test for neutrino properties, e.g. flavor oscillations
(for which upward moving tau's would be a unique signature) and coupling to
gravity, with an accuracy many orders of magnitude better than is currently
possible.

</DOC>
<DOC>
<DOCNO> 178597 </DOCNO>
Rotational properties of $^{252, 253, 254}$No. Influence of pairing


  Rotational bands of $^{252, 253, 254}$No and the fission barriers of
$^{254}$No at spin 0$\hbar$ and 20$\hbar$ are calculated with the
Hartree-Fock-Bogolyubov theory and the Lipkin-Nogami approximate particle
number projection. The SLy4 Skyrme force is used in the particle-hole channel.
A zero-range force with and without density-dependence is used in the
particle-particle channel. The experimental ground state deformation
(${\cal{Q}}_{20}$ = 32.8 b) is reproduced as well as the increase of the
dynamical moment of inertia with frequency both for $^{252}$No and $^{254}$No.
 The rotational band of $^{253}$No is also calculated. Fission barriers of
$^{254}$No at spin 0$\hbar$ and 20$\hbar$ show the robustness of
shell-corrections against rotation in these heavy nuclei.

</DOC>
<DOC>
<DOCNO> 150958 </DOCNO>
Chiral forms and their deformations


  We systematically study deformations of chiral forms with applications to
string theory in mind. To first order in the coupling constant, this problem
can be translated into the calculation of the local BRST cohomological group at
ghost number zero. We completely solve this cohomology and present detailed
proofs of results announced in a previous letter. In particular, we show that
there is no room for non-abelian, local, deformations of a pure system of
chiral p-forms.

</DOC>
<DOC>
<DOCNO> 174613 </DOCNO>
Centrality Dependence of Charged Particle Multiplicity in Au-Au


  We present results for the charged-particle multiplicity distribution at
mid-rapidity in Au - Au collisions at sqrt(s_NN)=130 GeV measured with the
PHENIX detector at RHIC. For the 5% most central collisions we find
$dN_{ch}/d\eta_{|\eta=0} = 622 \pm 1 (stat) \pm 41 (syst)$. The results,
analyzed as a function of centrality, show a steady rise of the particle
density per participating nucleon with centrality.

</DOC>
<DOC>
<DOCNO> 151722 </DOCNO>
On the harmonic superspace language adapted to the Gelfand-Dickey


  Methods developed for the analysis of non-linear integrable models are used
in the harmonic superspace (HS) framework. These methods, when applied to the
HS, can lead to extract more information about the meaning of integrability in
non-linear physical problems. Among the results obtained, we give the basic
ingredients towards building in the HS language the analogue of the G.D.
algebra of pseudo-differential operators. Some useful convention notations and
algebraic structures are also introduced to make the use of the harmonic
superspace techniques more accessible.

</DOC>
<DOC>
<DOCNO> 151064 </DOCNO>
4D Gravity on a Brane in 5D Minkowski Space


  We suggest a mechanism by which four-dimensional Newtonian gravity emerges on
a 3-brane in 5D Minkowski space with an infinite size extra dimension. The
worldvolume theory gives rise to the correct 4D potential at short distances
whereas at large distances the potential is that of a 5D theory. We discuss
some phenomenological issues in this framework.

</DOC>
<DOC>
<DOCNO> 100825 </DOCNO>
Newtonian normal shift in multidimensional Riemannian geometry


  Explicit description for arbitrary Newtonian dynamical system admitting the
normal shift in Riemannian manifold of the dimension $n\geq 3$ is found. On the
base of this result the kinematics of normal shift of hypersurfaces along
trajectories of such system is studied.

</DOC>
<DOC>
<DOCNO> 119722 </DOCNO>
Chromospheric Activity in Metal-Poor Dwarfs


  We have obtained echelle spectra with the Hubble Space Telescope (HST) of the
MgII 2800A region of ten stars whose metallicities range from 1/300 to 1/3 that
of the Sun, and whose space velocities suggest a halo or old thick-disk origin.
Spectra of all ten show double-peaked emission in the MgII core, very much like
the quiet Sun. A half-dozen non-rotating stars were observed more than once,
and show at most a low level of variability in the emission flux, comparable to
that of quiet stars of solar metallicity. For four stars, we have obtained
Lyman-alpha spectra at 0.2A resolution; all four show emission. The data thus
strongly suggest that chromospheric activity at a minimum level is present in
all stars of near-solar temperature, regardless of age or metallicity. While
this points to non-magnetic sources such as acoustic waves, a contribution from
globally-organized magnetic fields is possible at a low level. We plan a longer
series of MgII and Lyman alpha observations to constrain this.

</DOC>
<DOC>
<DOCNO> 170299 </DOCNO>
Quantum copying can increase the practically available information


  While it is known that copying a quantum system does not increase the amount
of information obtainable about the originals, it may increase the amount
available in practice, when one is restricted to imperfect measurements. We
present a detection scheme which using imperfect detectors, and possibly noisy
quantum copying machines (that entangle the copies), allows one to extract more
information from an incoming signal, than with the imperfect detectors alone.
The case of single-photon detection with noisy, inefficient detectors and
copiers (single controlled-NOT gates in this case) is investigated in detail.
The improvement in distinguishability between a photon and vacuum is found to
occur for a wide range of parameters, and to be quite robust to random noise.
The properties that a quantum copying device must have to be useful in this
scheme are investigated.

</DOC>
<DOC>
<DOCNO> 7894 </DOCNO>
Destruction of long-range antiferromagnetic order by hole doping


  We study the renormalization of the staggered magnetization of a
two-dimensional antiferromagnet as a function of hole doping, in the framework
of the t-J model. It is shown that the motion of holes generates decay of spin
waves into ''particle-hole'' pairs, which causes the destruction of the
long-range magnetic order at a small hole concentration. This effect is mainly
determined by the coherent motion of holes. The value obtained for the critical
hole concentration, of a few percent, is consistent with experimental data for
the doped copper oxide high-Tc superconductors.

</DOC>
<DOC>
<DOCNO> 84385 </DOCNO>
Singularities in General Relativity coupled to nonlinear electrodynamics


  We study here some consequences of the nonlinearities of the electromagnetic
field acting as a source of Einstein's equations on the propagation of photons.
We restrict to the particular case of a ``regular black hole'', and show that
there exist singularities in the effective geometry. These singularities may be
hidden behind a horizon or naked, according to the value of a parameter. Some
unusual properties of this solution are also analyzed.

</DOC>
<DOC>
<DOCNO> 9635 </DOCNO>
Evolution and Ageing


  The idea of this review is to connect the different models of evolution to
those of biological ageing through Darwin's theory. We start with the Eigen
model of quasispecies for microevolution, then introduce the Bak-Sneppen model
for macroevolution and, finally, present the Penna model for biological ageing
and some of its most important results. We also explore the concept of
coevolution using this model.

</DOC>
<DOC>
<DOCNO> 71886 </DOCNO>
A Constrained Standard Model from a Compact Extra Dimension


  A SU(3) \times SU(2) \times U(1) supersymmetric theory is constructed with a
TeV sized extra dimension compactified on the orbifold S^1/(Z_2 \times Z_2').
The compactification breaks supersymmetry leaving a set of zero modes which
correspond precisely to the states of the 1 Higgs doublet standard model.
Supersymmetric Yukawa interactions are localized at orbifold fixed points. The
top quark hypermultiplet radiatively triggers electroweak symmetry breaking,
yielding a Higgs potential which is finite and exponentially insensitive to
physics above the compactification scale. This potential depends on only a
single free parameter, the compactification scale, yielding a Higgs mass
prediction of 127 \pm 8 GeV. The masses of the all superpartners, and the
Kaluza-Klein excitations are also predicted. The lightest supersymmetric
particle is a top squark of mass 197 \pm 20 GeV. The top Kaluza-Klein tower
leads to the \rho parameter having quadratic sensitivity to unknown physics in
the ultraviolet.

</DOC>
<DOC>
<DOCNO> 80737 </DOCNO>
Strong Non-Ultralocality of Ginsparg-Wilson Fermionic Actions


  It is shown that it is impossible to construct a free theory of fermions on
infinite hypercubic Euclidean lattice in even number of dimensions that: (a) is
ultralocal, (b) respects the symmetries of hypercubic lattice, (c) chirally
nonsymmetric part of its propagator is local, and (d) describes single species
of massless Dirac fermions in the continuum limit. This establishes
non-ultralocality for arbitrary doubler-free Ginsparg-Wilson fermionic action
with hypercubic symmetries ("strong non-ultralocality"), and complements the
earlier general result on non-ultralocality of infinitesimal
Ginsparg-Wilson-Luscher symmetry transformations ("weak non-ultralocality").

</DOC>
<DOC>
<DOCNO> 174556 </DOCNO>
Sub-barrier fusion of drip-line nuclei


  We discuss the role of break-up process of a loosely-bound projectile in
subbarrier fusion reactions. Coupled-channels calculations are carried out for
$^{11}$Be + $^{208}$Pb and $^{4,6}$He + $^{238}$U reactions by discretizing in
energy the particle continuum states. Our calculations show that the coupling
to the break-up channel has two effects, namely the loss of flux and the
dynamical modulation of fusion potential. Their net effects differ depending on
the energy region. At energies above the Coulomb barrier, the former effect
dominates over the latter and cross sections for complete fusion are hindered
compared with the no coupling case. On the other hand, at below the barrier,
the latter effect is much larger than the former and complete fusion cross
sections are enhanced consequently.

</DOC>
<DOC>
<DOCNO> 40541 </DOCNO>
Diffraction in hadron-hadron interactions


  Results on soft and hard diffraction in $pp$ and $\bar pp$ collisions are
reviewed with emphasis on factorization and scaling properties of differential
cross sections. While conventional factorization breaks down at high energies,
a scaling behavior emerges, which leads to a universal description of
diffractive processes in terms of a (re)normalized rapidity gap probability
distribution.

</DOC>
<DOC>
<DOCNO> 117357 </DOCNO>
Limits on the Spatial Extent of AGN Measured with the Fine Guidance


  The optical structure of several AGN has been studied using the Fine Guidance
Sensors (FGS) on the Hubble Space Telescope (HST). The FGSs are interferometric
devices which can resolve structure on scales of 20 milliarcsecs or less and
hence have the potential to improve on the resolution attainable by HST's
cameras. The FGSs produce interferometric fringes known as S-curves which are
related to the intensity profile of the object on the sky. These have been
analyzed using a simple model for the radial intensity distribution and
strength of the underlying background illumination of the observed objects.
Eight different observations of six different AGN have been analyzed. No
statistically significant differences from point sources are detected but
significant upper limits of order 20 milliarcseconds are placed on any spatial
extent. Systematic effects limiting the resolution are discussed and some
simple conclusions about the physical size and luminosity densities of the
emitting regions of the AGN implied by the data are given.

</DOC>
<DOC>
<DOCNO> 170402 </DOCNO>
One- and two-dimensional N-qubit systems in capacitively coupled quantum


  Coulomb blockade effects in capacitively coupled quantum dots can be utilized
for constructing an N-qubit system with antiferromagnetic Ising interactions.
Starting from the tunneling Hamiltonian, we theoretically show that the
Hamiltonian for a weakly coupled quantum-dot array is reduced to that for
nuclear magnetic resonance (NMR) spectroscopy. Quantum operations are carried
out by applying only electrical pulse sequences. Thus various error-correction
methods developed in NMR spectroscopy and NMR quantum computers are applicable
without using magnetic fields. A possible measurement scheme in an N-qubit
system is quantitatively discussed.

</DOC>
<DOC>
<DOCNO> 85170 </DOCNO>
Vacuum Effects in Gravitational Fields: Theory and Detectability


  In this thesis, we investigate quantum vacuum effects in the presence of
gravitational fields. After discussing the general theory of vacuum effects in
strong fields we apply it to the relevant issue of the interaction of the
quantum vacuum with black hole geometries. In particular we consider the
long-standing problem of the interpretation of gravitational entropy. After
these investigations, we discuss the possible experimental tests of particle
creation from the quantum vacuum. This leads us to study acoustic geometries
and their way of ``simulating'' gravitational structures, such as horizons and
black holes. We study the stability of these structures and the problems
related to setting up experimental detection of ``phonon Hawking flux'' from
acoustic horizons. This line of research then leads us to propose a new model
for explaining the emission of light in the phenomenon of Sonoluminescence,
based on the dynamical Casimir effect. This is possibly amenable to
experimental investigation. Finally we consider high energy phenomena in the
early universe. In particular we discuss inflation and possible alternative
frameworks for solving the cosmological puzzles.

</DOC>
<DOC>
<DOCNO> 119273 </DOCNO>
RXTE Studies of X-ray Spectral Variations with Accretion Rate in 4U


  We present the results of detailed spectral studies of the ultra-compact low
mass X-ray binary (LMXB) 4U 1915-05 carried out with the Rossi X-ray Timing
Explorer (RXTE) during 1996. 4U 1915-05 is an X-ray burster (XRB) known to
exhibit a ~199-day modulation in its 2--12 keV flux. Observations were
performed with the PCA and HEXTE instruments on RXTE at roughly one-month
intervals to sample this long-term period and study accretion rate-related
spectral changes. We obtain good fits with a model consisting of a blackbody
and an exponentially cut-off power law. The spectral parameters are strongly
correlated with both the broad-band (2--50 keV) luminosity and the position in
the color-color diagram, with the source moving from a low hard state to a high
soft state as the accretion rate increases. The blackbody component appears to
drive the spectral evolution. Our results are consistent with a geometry in
which the soft component arises from an optically thick boundary layer and the
hard component from an extended Comptonizing corona. Comparing our results with
those of a similar study of the brighter source 4U 1820-30 (Bloser et al.
2000), we find that the two ultra-compact LMXBs occupy similar spectral states
even though the transitions occur at very different total luminosities.

</DOC>
<DOC>
<DOCNO> 84335 </DOCNO>
Close limit of grazing black hole collisions: non-spinning holes


  Using approximate techniques we study the final moments of the collision of
two (individually non-spinnning) black holes which inspiral into each other.
The approximation is based on treating the whole space-time as a single
distorted black hole. We obtain estimates for the radiated energy, angular
momentum and waveforms for the gravitational waves produced in such a
collision. The results can be of interest for analyzing the data that will be
forthcoming from gravitational wave interferometric detectors, like the LIGO,
GEO, LISA, VIRGO and TAMA projects.

</DOC>
<DOC>
<DOCNO> 70128 </DOCNO>
The Renormalization Group Improvement of the QCD Static Potentials


  We resum the leading ultrasoft logs of the singlet and octet static QCD
potentials within potential NRQCD. We then obtain the complete three-loop
renormalization group improvement of the singlet QCD static potential. The
discrepancies between the perturbative evaluation and the lattice results at
short distances are slightly reduced.

</DOC>
<DOC>
<DOCNO> 99775 </DOCNO>
Bass's Work in Ring Theory and Projective Modules


  The early papers of Hyman Bass in the late 50s and the early 60s leading up
to his pioneering work in algebraic K-theory have played an important and very
special role in ring theory and the theory of projective (and injective)
modules. In this article, we give a general survey of Bass's fundamental
contributions in this early period of his work, and explain how much this work
has influenced and shaped the thinking of subsequent researchers in the area.

</DOC>
<DOC>
<DOCNO> 12492 </DOCNO>
Parquet approach to nonlocal vertex functions and electrical


  A diagrammatic technique for two-particle vertex functions is used to
describe systematically the influence of spatial quantum coherence and
backscattering effects on transport properties of noninteracting electrons in a
random potential. In analogy with many-body theory we construct parquet
equations for topologically distinct {\em nonlocal} irreducible vertex
functions into which the {\em local} one-particle propagator and two-particle
vertex of the coherent-potential approximation (CPA) enter as input. To
complete the two-particle parquet equations we use an integral form of the Ward
identity and determine the one-particle self-energy from the known irreducible
vertex. In this way a conserving approximation with (Herglotz) analytic
averaged Green functions is obtained. We use the limit of high spatial
dimensions to demonstrate how nonlocal corrections to the $d=\infty$ (CPA)
solution emerge. The general parquet construction is applied to the calculation
of vertex corrections to the electrical conductivity. With the aid of the
high-dimensional asymptotics of the nonlocal irreducible vertex in the
electron-hole scattering channel we derive a mean-field approximation for the
conductivity with vertex corrections. The impact of vertex corrections onto the
electronic transport is assessed quantitatively within the proposed mean-field
description on a binary alloy.

</DOC>
<DOC>
<DOCNO> 100864 </DOCNO>
Avoiding maximal parabolic subgroups of S_k


  We find an explicit expression for the generating function of the number of
permutations in S_n avoiding a subgroup of S_k generated by all but one simple
transpositions. The generating function turns out to be rational, and its
denominator is a rook polynomial for a rectangular board.

</DOC>
<DOC>
<DOCNO> 68886 </DOCNO>
Remarks on the Boomerang results, the baryon density and the leptonic


  The very recent Boomerang results give an estimate of unprecedented precision
of the Cosmic Microwave Background anisotropies on sub--degree scales. A
puzzling feature for theoretical cosmology is the low amplitude of the second
acoustic peak. Through a qualitative discussion, we argue that a scarcely
considered category of flat models, with a leptonic asymmetry, a high baryon
density and a low cosmological constant seems to be in very good agreement with
the data, while still being compatible with big bang nucleosynthesis and some
other observational constraints. Although this is certainly not the only way to
explain the data, we believe that these models deserve to be included in
forthcoming likelihood analyses.

</DOC>
<DOC>
<DOCNO> 120566 </DOCNO>
Observations of Spectral and Time Variabilities from MCG-2-58-22


  We present results from analysis of the X-ray archive data of MCG-2-58-22,
acquired with ROSAT from 1991 to 1993 and with ASCA from 1993 to 1997. By
analyzing light curves, we find that MCG-2-58-22 shows a clear time variability
in X-ray flux. The time scales of the variations range widely from about 1000 s
to more than years. Among the variations, a flare-like event overlaid on the
gradual flux decrease from 1979 to 1993 is detected. We also find clear time
variability of the spectra in the energy range of 0.1 - 2.0 keV. However, the
flux variation does not influences on their spectra in the energy range of 2 -
10 keV. The implications of these observational results are discussed in terms
of a supermassive black hole model and accretion flow dynamics near the central
black hole.

</DOC>
<DOC>
<DOCNO> 70926 </DOCNO>
Electromagnetic corrections to the hadronic phase shifts in low energy


  We calculate the s and p-wave electromagnetic corrections which must be
subtracted from the nuclear phase shifts obtained from the analysis of low
energy pi+p elastic scattering data, in order to obtain hadronic phase shifts.
We compare our results with earlier calculations and estimate the uncertainties
in the corrections.

</DOC>
<DOC>
<DOCNO> 99994 </DOCNO>
Consistently there is no non trivial ccc forcing notion with the Sacks


  Boban Velickovic asked the following question: Is there a nontrivial forcing
notion with the Sacks property which is also ccc? A ``definable'' variant of
this question has been answered in [Sh:480] (math.LO/9303208): Every nontrivial
Souslin forcing notion which has the Sacks property has an uncountable
antichain. Here we show that it is consistent that every nontrivial forcing
notion which has the Sacks property has an uncountable antichain.
Independently, Velickovic has also proved the consistency of this statement.

</DOC>
<DOC>
<DOCNO> 72221 </DOCNO>
Open and Hidden Charm Production in Heavy Ion Collisions at


  We consider the production of the open charm and J/psi mesons in heavy ion
collisions at BNL RHIC. We discuss several recently developed pictures for
J/psi production and argue that a measurement at RHIC energies is crucial for
disentangling these different descriptions.

</DOC>
<DOC>
<DOCNO> 118039 </DOCNO>
Resonant scattering of X-rays by the warm intergalactic medium


  For the low density filamentary and sheet-like structures in the warm ($\sim
10^4$ to $\sim 10^6$ K) IGM predicted by numerical simulations the resonant
line scattering of X-ray background (XRB) photons by He and H-like ions of
heavy elements can exceed the ``local'' thermal emission by a factor of a few
or more. Due to the conservative nature of scattering this resonantly scattered
radiation can only be identified if a significant fraction of the XRB is
resolved and removed. While the combined spectrum of the resolved sources will
contain X-ray absorption features, the residual background will contain
corresponding emission features with the same intensity. At the relevant
densities and temperatures the lines of He and H-like oxygen at 0.57 and 0.65
keV are most promising. These lines (which have a typical width of $\sim$ 1-2
eV) may contain up to 50% of the total 0.5-1 keV emission of the filament. For
a nearby ($z \la 0.1$) filament with a Thomson optical depth of $10^{-4}$ XMM
should detect about 200 photons in the OVII line during a $10^5$ s exposure if
the metallicity of the gas is as large as observed in galaxy clusters. On
average up to a few percent of the soft XRB could be resonantly scattered by
this phase of the IGM and resonantly scattered photons should account for a
significant fraction of the truly diffuse background at low energies. Close to
bright X-ray sources like galaxy clusters or AGN the flux of scattered
radiation will be further enhanced. Off-line blazars are the most promising
illuminating sources. The scattered emission from AGN may also constrain the
duration of the active phase of these objects.

</DOC>
<DOC>
<DOCNO> 117047 </DOCNO>
Breaking of vortex lines - a new mechanism of collapse in hydrodynamics


  A new mechanism of the collapse in hydrodynamics is suggested, due to
breaking of continuously distributed vortex lines. Collapse results in
formation of the point singularities of the vorticity field $|{\bf\Omega}|$. At
the collapse point, the value of the vorticity blows up as $(t_0-t)^{-1}$ where
$t_0$ is a collapse time. The spatial structure of the collapsing distribution
approaches a pancake form: contraction occurs by the law $l_1\sim(t_0-t)^{3/2}$
along the "soft" direction, the characteristic scales vanish like
$l_2\sim(t_0-t)^{1/2}$ along two other ("hard") directions. This scenario of
the collapse is shown to take place in the integrable three-dimensional
hydrodynamics with the Hamiltonian ${\cal H}=\int|{\bf\Omega}|d{\bf r}$. Most
numerical studies of collapse in the Euler equation are in a good agreement
with the proposed theory.

</DOC>
<DOC>
<DOCNO> 150594 </DOCNO>
Scalar Quartic Effective Action on $AdS_5$


  We review the recent results concerning the computation of cubic and quartic
couplings of scalar fields in type IIB supergravity on AdS_5\times S^5
background that are dual to (extended) chiral primary operators in N=4 SYM_4.
We discuss the vanishing of certain cubic and quartic couplings and
non-renormalization property of corresponding correlators in the conformal
field theory

</DOC>
<DOC>
<DOCNO> 174492 </DOCNO>
Gamow-Teller Strengths of the Inverse-Beta Transition 176Yb --> 176Lu


  Discrete Gamow-Teller (GT) transitions, 176Yb-->176Lu at low excitation
energies have been measured via the (3He,t) reaction at 450 MeV and at 0
degrees. For 176Yb, two low-lying states are observed, setting low thresholds
Q(neutrino)=301 and 445 keV for neutrino capture. Capture rates estimated from
the measured GT strengths, the simple two-state excitation structure, and the
low Q(neutrino) in Yb--Lu indicate that Yb-based neutrino-detectors are well
suited for a direct measurement of the complete sub-MeV solar electron-neutrino
spectrum (including pp neutrinos) where definitive effects of flavor conversion
are expected.

</DOC>
<DOC>
<DOCNO> 99595 </DOCNO>
Index and Dynamics of Quantized Contact Transformations


  Quantized contact transformations are Toeplitz operators over a contact
manifold $(X,\alpha)$ of the form $U_{\chi} = \Pi A \chi \Pi$, where $\Pi :
H^2(X) \to L^2(X)$ is a Szego projector, where $\chi$ is a contact
transformation and where $A$ is a pseudodifferential operator over $X$. They
provide a flexible alternative to the Kahler quantization of symplectic maps,
and encompass many of the examples in the physics literature, e.g. quantized
cat maps and kicked rotors. The index problem is to determine $ind(U_{\chi})$
when the principal symbol is unitary, or equivalently to determine whether $A$
can be chosen so that $U_{\chi}$ is unitary. We show that the answer is yes in
the case of quantized symplectic torus automorphisms $g$---by showing that
$U_g$ duplicates the classical transformation laws on theta functions. Using
the Cauchy-Szego kernel on the Heisenberg group, we calculate the traces on
theta functions of each degree N. We also study the quantum dynamics generated
by a general q.c.t. $U_{\chi}$, i.e. the quasi-classical asymptotics of the
eigenvalues and eigenfunctions under various ergodicity and mixing hypotheses
on $\chi.$ Our principal results are proofs of equidistribution of
eigenfunctions $\phi_{Nj}$ and weak mixing properties of matrix elements
$(B\phi_{Ni}, \phi_{Nj})$ for quantizations of mixing symplectic maps.

</DOC>
<DOC>
<DOCNO> 152585 </DOCNO>
On Relativistic Brane Probes in Singular Spacetimes


  We study the relativistic dynamics of brane probes in singular warped
spacetimes and establish limits for such analysis. The behavior of the
semiclassical brane probe wave functions implies that unitarity boundary
conditions can be imposed at the singularity.

</DOC>
<DOC>
<DOCNO> 117694 </DOCNO>
Chemical enrichment and star formation in the Milky Way disk; I. Sample


  The age-metallicity relation of the solar neighbourhood is studied using a
sample of 552 late-type dwarfs. This sample was built from the intersection of
photometric catalogues with chromospheric activity surveys of the Mount Wilson
group. For these stars, metallicities were estimated from uvby data, and ages
were calculated from their chromospheric emission levels using a new
metallicity-dependent chromospheric activity-age relation developed by
Rocha-Pinto & Maciel (1998). A careful estimate of the errors in the
chromospheric age is made. The errors in the chromospheric indices are shown to
include partially the effects of the stellar magnetic cycles, although a
detailed treatment of this error is still beyond our knowledge. It is shown
that the results are not affected by the presence of unresolved binaries in the
sample. We derive an age-metallicity relation which confirms the mean trend
found by previous workers. The mean metallicity shows a slow, steady increase
with time, amounting at least 0.56 dex in 15 Gyr. The initial metallicity of
the disk is around -0.70 dex, in agreement with the G dwarf metallicity
distribution. According to our data, the intrinsic cosmic dispersion in metal
abundances is around 0.13 dex, a factor of two smaller than that found by
Edvardsson et al. (1993). We show that chromospheric ages are compatible with
isochrone ages, within the expected errors, so that the difference in the
scatter cannot be caused by the accuracy of our ages and metallicities. This
reinforces some suggestions that the Edvarsson et al.'s sample is not suitable
to the determination of the age-metallicity relation.

</DOC>
<DOC>
<DOCNO> 121348 </DOCNO>
Global VLBI Observations of HI Absorption toward NGC 3894


  One of the most important problems in the study of AGN is understanding the
detailed geometry, physics, and evolution of the central engines and their
environments. The leading models involve an accretion disk and torus around a
central black hole. Much of this torus should be comprised of atomic gas,
detectable in absorption toward the bright inner radio jets. In the last few
years, a number of compact symmetric radio sources have been found to exhibit
HI absorption, at or near the systemic velocity, toward the central parsecs.
Understanding the kinematics of the HI detected toward the central parsecs of
these sources will provide an important test of this model and of unified
schemes for AGN. We present results of Global VLBI Network observations at 1.4
GHz toward the active nucleus of the nearby elliptical galaxy NGC 3894 (a.k.a.
1146+596, z=0.01068). The center of activity in this source and the orientation
of the jets with respect to our line of sight have been determined using VLBI
studies of the proper motions of jet components. The 21 cm atomic hydrogen line
is seen in absorption slightly redshifted with respect to the systemic velocity
toward the core, jet, and counterjet of this source. The structure of the HI in
this source is complicated. We find several distinct components present along
the lines of sight to the approaching and receding jets, making interpretation
challenging.

</DOC>
<DOC>
<DOCNO> 12012 </DOCNO>
Dynamic scaling theory of the Kosterlitz-Thouless-Berezinskii


  A numerical study of the neutral two-dimensional (2D) lattice Coulomb gas is
performed to examine dynamic scaling, finite size effects, and the dynamic
critical exponent $z$ of the Kosterlitz-Thouless-Berezinskii transition. By
studying large system sizes ($L=100$), we show $z=2.0 \pm0.2$ using
Fisher-Fisher-Huse (FFH) scaling. We also present evidence that the vortex
correlation length is finite below the transition temperature, in contrast to
conventional wisdom. Finally, we conclude that previous findings for a variety
of experimental systems that $z\simeq 5.6$ using FFH scaling indicates that
finite size effects are ubiquitous in 2D superconductors and Josephson Junction
Arrays.

</DOC>
<DOC>
<DOCNO> 7792 </DOCNO>
Scaling exponents for Barkhausen avalanches in polycrystals and


  We investigate the scaling properties of the Barkhausen effect, recording the
noise in several soft ferromagnetic materials: polycrystals with different
grain sizes and amorphous alloys. We measure the Barkhausen avalanche
distributions and determine the scaling exponents. In the limit of vanishing
external field rate, we can group the samples in two distinct classes,
characterized by exponents \tau = 1.50 \pm 0.05 or \tau = 1.27 \pm 0.03, for
the avalanche size distributions. We interpret these results in terms of the
depinning transition of domain walls and obtain an expression relating the
cutoff of the distributions to the demagnetizing factor which is in
quantitative agreement with experiments.

</DOC>
<DOC>
<DOCNO> 13489 </DOCNO>
Triplet superconductivity induced by screened phonon interactions in


  We propose that screened pairing interactions mediated by phonons could give
rise to a spin triplet superconductivity in ferromagnetic compounds such as
UGe_2. It is pointed out that the pairing interactions include anisotropic
components such as those of p, d, f-waves in addition to dominant s-wave
component due to the momentum dependence. Since the ferromagnetic long-range
order coexists, there is a large splitting of the Fermi surfaces of up and down
spin electrons, which suppresses singlet pairing. Therefore, triplet pairing
occurs at last due to the sub-dominant anisotropic interactions, even in the
absence of magnetic contribution to the pairing interactions.

</DOC>
<DOC>
<DOCNO> 11221 </DOCNO>
Adaptation of Autocatalytic Fluctuations to Diffusive Noise


  Evolution of a system of diffusing and proliferating mortal reactants is
analyzed in the presence of randomly moving catalysts. While the continuum
description of the problem predicts reactant extinction as the average growth
rate becomes negative, growth rate fluctuations induced by the discrete nature
of the agents are shown to allow for an active phase, where reactants
proliferate as their spatial configuration adapts to the fluctuations of the
catalysts density. The model is explored by employing field theoretical
techniques, numerical simulations and strong coupling analysis. For d<=2, the
system is shown to exhibits an active phase at any growth rate, while for d>2 a
kinetic phase transition is predicted. The applicability of this model as a
prototype for a host of phenomena which exhibit self organization is discussed.

</DOC>
<DOC>
<DOCNO> 152018 </DOCNO>
Light-cone Superstring in AdS Space-time


  We consider fixing the bosonic light-cone gauge for string in AdS in the
phase space framework, i.e. by choosing $x^+ = \tau$, and by choosing $\sigma$
so that $P^+$ is distributed uniformly (its density is independent of
$\sigma$). We discuss classical bosonic string in AdS space and superstring in
AdS_5 x S^5. In the latter case the starting point is the action found in
hep-th/0007036 where the kappa-symmetry is fixed by a fermionic light cone
gauge. We derive the light cone Hamiltonian in the AdS_5 x S^5 case and in the
case of superstring in AdS_3 x S^3. We also obtain a realization of the
generators of the basic symmetry superalgebra psu(2,2|4) in terms of the AdS_5
x S^5 superstring coordinate fields.

</DOC>
<DOC>
<DOCNO> 170565 </DOCNO>
Number Partitioning on a Quantum Computer


  We present an algorithm to compute the number of solutions of the
(constrained) number partitioning problem. A concrete implementation of the
algorithm on an Ising-type quantum computer is given.

</DOC>
<DOC>
<DOCNO> 13491 </DOCNO>
Frequency Dependence of Aging, Rejuvenation and Memory in a disordered


  We characterize in details the aging properties of the ferroelectric phase of
K Ta_{1-x} Nb_x O_3 (KTN), where both rejuvenation and (partial) memory are
observed. In particular, we carefully examine the frequency dependence of
several quantities that characterize aging, rejuvenation and memory. We find a
marked subaging behaviour, with an a.c. dielectric susceptiblity scaling as
$\omega \sqrt{t_w}$, where $t_w$ is the waiting time. We suggest an
interpretation in terms of pinned domain walls, much along the lines proposed
for aging in a disordered ferromagnet, where both domain wall reconformations
and overall (cumulative) domain growth are needed to rationalize the
experimental findings.

</DOC>
<DOC>
<DOCNO> 12200 </DOCNO>
SrCu_2(BO_3)_2 - a Two Dimensional Spin Liquid


  We study an extended Shastry-Sutherland model for SrCu_2(BO_3)_2 and analyze
the low lying parts of the energy spectrum by means of a perturbative unitary
transformation based on flow equations. The derivation of the 1-magnon
dispersion (elementary triplets) is discussed. Additionally, we give a
quantitative description (symmetries and energies) of bound states made from
two elementary triplets. Our high order results allow to fix the model
parameters for SrCu_2(BO_3)_2 precisely: J_1=6.16(10)meV, x:=J_2/J_1=0.603(3),
J_\perp=1.3(2)meV. To our knowledge this is the first quantitative treatment of
bound states in a true 2d model.

</DOC>
<DOC>
<DOCNO> 174454 </DOCNO>
Measurement of the vector analyzing power in elastic electron-proton


  We report the first measurement of the vector analyzing power in inclusive
transversely polarized elastic electron-proton scattering at Q^2 = 0.1
(GeV/c)^2 and large scattering angles. This quantity should vanish in the
single virtual photon exchange, plane wave impulse approximation for this
reaction, and can therefore provide information on double photon exchange
amplitudes for electromagnetic interactions with hadronic systems. We find a
non-zero value of A=-15.4+/-5.4 ppm. No calculations of this observable for
nuclei other than spin 0 have been carried out in these kinematics, and the
calculation using the spin orbit interaction from a charged point nucleus of
spin 0 cannot describe these data.

</DOC>
<DOC>
<DOCNO> 151603 </DOCNO>
Symmetry Restoration and Tachyon Condensation in Open String Theory


  It has recently been argued that D-branes in bosonic string theory can be
described as noncommutative solitons, outside whose core the tachyon is
condensed to its ground state. We conjecture that, in addition, the local U(1)
gauge symmetry is restored to a $U(\infty)$ symmetry in the vacuum outside this
core. We present new solutions obeying this boundary condition. The tension of
these solitons agrees exactly with the expected D-brane tension for arbitrary
noncommutativity parameter $\t$, which effectively becomes a dynamical
variable. The restored $U(\infty)$ eliminates unwanted extra modes which might
otherwise appear outside the soliton core.

</DOC>
<DOC>
<DOCNO> 84275 </DOCNO>
Large quantum gravity effects: Cylindrical waves in four dimensions


  Linearly polarized cylindrical waves in four-dimensional vacuum gravity are
mathematically equivalent to rotationally symmetric gravity coupled to a
Maxwell (or Klein-Gordon) field in three dimensions. The quantization of this
latter system was performed by Ashtekar and Pierri in a recent work. Employing
that quantization, we obtain here a complete quantum theory which describes the
four-dimensional geometry of the Einstein-Rosen waves. In particular, we
construct regularized operators to represent the metric. It is shown that the
results achieved by Ashtekar about the existence of important quantum gravity
effects in the Einstein-Maxwell system at large distances from the symmetry
axis continue to be valid from a four-dimensional point of view. The only
significant difference is that, in order to admit an approximate classical
description in the asymptotic region, states that are coherent in the Maxwell
field need not contain a large number of photons anymore. We also analyze the
metric fluctuations on the symmetry axis and argue that they are generally
relevant for all of the coherent states.

</DOC>
<DOC>
<DOCNO> 117402 </DOCNO>
Radiative Processes and Geometry of Spectral States of Black-Hole


  I review radiative processes responsible for X-ray emission in the hard (low)
and soft (high) spectral states of black-hole binaries. The main process in the
hard state appears to be thermal Comptonization (in a hot plasma) of blackbody
photons emitted by a cold disk. This is supported by correlations between the
spectral index, the strength of Compton reflection, and the peak frequencies in
the power density spectrum, as well as by the frequency-dependence of
Fourier-resolved spectra. Spectral variability may then be driven by the
variable truncation radius of the disk. The soft state appears to correspond to
the smallest truncation radii. However, the lack of high-energy cutoffs
observed in the soft state implies that its main radiative process is Compton
scattering of disk photons by non-thermal electrons. The bulk-motion
Componization model for the soft state is shown to be ruled out by the data.

</DOC>
<DOC>
<DOCNO> 170139 </DOCNO>
Quantum Computing by Two-Dimensional NMR using Spin- and


  Quantum computing using two-dimensional NMR has recently been described using
scalar coupling evolution technique [J. Chem. Phys.,109,10603 (1998)]. In the
present paper, we describe two-dimensional NMR quantum computing with the help
of selective pulses. A number of logic gates are implemented using two and
three qubits with one extra observer spin. Some many-in-one gates (or
Portmanteau gates) are implemented. Toffoli gate (or AND/NAND gate) and OR/NOR
gates are implemented on three qubits. Deutsch-Jozsa quantum algorithm for one
and two qubits, using one extra work qubit, has also been implemented using
selective pulses after creating a coherent superposition state, in the
two-dimensional methodology.

</DOC>
<DOC>
<DOCNO> 101179 </DOCNO>
On the Classification of Finite-Dimensional Triangular Hopf Algebras


  A fundamental problem in the theory of Hopf algebras is the classification
and explicit construction of finite-dimensional quasitriangular Hopf algebras
over C. These Hopf algebras constitute a very important class of Hopf algebras,
introduced by Drinfeld (e.g. the quantum double of a Hopf algebra). However,
this intriguing problem turns out to be extremely hard and it is still widely
open. One can hope that resolving the problem in the triangular case would
contribute to the understanding of the general case. There is no complte
classification of finite-dimensional triangular Hopf algebras yet. However, the
problem was solved in the semisimple case by Etingof and the author, in the
minimal triangular pointed case by the author, and more generally for
triangular Hopf algebras with the Chevalley property by Andruskiewitsch,
Etingof and the author. The purpose of this paper is to report on all of this
progress, and to explain in full details the mathematics and ideas involved in
this theory. The classification in the semisimple case relies on Deligne's
theorem on Tannakian categories and on Movshev's theory in an essential way. We
explian Movshev's theory in details, and refer the reader to math.QA/0007147
for a detailed discussion of the first aspect. We also discuss the existence of
grouplike elements in quasitriangular semisimple Hopf algebras, and the
representation theory of cotriangular semisimple Hopf algebras. We conclude the
paper with a list of related open problems.

</DOC>
<DOC>
<DOCNO> 119470 </DOCNO>
Monte Carlo Predictions of Far-Infrared Emission from Spiral Galaxies


  We present simulations of Far Infrared (FIR) emission by dust in spiral
galaxies, based on the Monte Carlo radiative transfer code of Bianchi, Ferrara
& Giovanardi (1996). The radiative transfer is carried out at several
wavelength in the Ultraviolet, optical and Near Infrared, to cover the range of
the stellar Spectral Energy Distribution (SED). Together with the images of the
galactic model, a map of the energy absorbed by dust is produced. Using
Galactic dust properties, the spatial distribution of dust temperature is
derived under the assumption of thermal equilibrium. A correction is applied
for non-equilibrium emission in the Mid Infrared. Images of dust emission can
then be produced at any wavelength in the FIR.
  We show the application of the model to the spiral galaxy NGC 6946. The
observed stellar SED is used as input and models are produced for different
star-dust geometries. It is found that only optically thick dust disks can
reproduce the observed amount of FIR radiation. However, it is not possible to
reproduce the large FIR scalelength suggested by recent observation of spirals
at 200 um, even when the scalelength of the dust disk is larger than that for
stars. Optically thin models have ratios of optical/FIR scalelengths closer to
the 200um observations, but with smaller absolute scalelengths than optically
thick cases. The modelled temperature distributions are compatible with
observations of the Galaxy and other spirals. We finally discuss the
approximations of the model and the impact of a clumpy stellar and dust
structure on the FIR simulations.

</DOC>
<DOC>
<DOCNO> 116442 </DOCNO>
Radiative recombination of bare Bi83+: Experiment versus theory


  Electron-ion recombination of completely stripped Bi83+ was investigated at
the Experimental Storage Ring (ESR) of the GSI in Darmstadt. It was the first
experiment of this kind with a bare ion heavier than argon. Absolute
recombination rate coefficients have been measured for relative energies
between ions and electrons from 0 up to about 125 eV. In the energy range from
15 meV to 125 eV a very good agreement is found between the experimental result
and theory for radiative recombination (RR). However, below 15 meV the
experimental rate increasingly exceeds the RR calculation and at Erel = 0 eV it
is a factor of 5.2 above the expected value. For further investigation of this
enhancement phenomenon the electron density in the interaction region was set
to 1.6E6/cm3, 3.2E6/cm3 and 4.7E6/cm3. This variation had no significant
influence on the recombination rate. An additional variation of the magnetic
guiding field of the electrons from 70 mT to 150 mT in steps of 1 mT resulted
in periodic oscillations of the rate which are accompanied by considerable
changes of the transverse electron temperature.

</DOC>
<DOC>
<DOCNO> 80829 </DOCNO>
Simulating Simplified Versions of the IKKT Matrix Model


  We simulate a supersymmetric matrix model obtained from dimensional reduction
of 4d SU(N) super Yang-Mills theory (a 4d counter part of the IKKT model or IIB
matrix model). The eigenvalue distribution determines the space structure. The
measurement of Wilson loop correlators reveals a universal large N scaling.
Eguchi-Kawai equivalence may hold in a finite range of scale, which is also
true for the bosonic case. We finally report on simulations of a low energy
approximation of the 10d IKKT model, where we omit the phase of the Pfaffian
and look for evidence for a spontaneous Lorentz symmetry breaking.

</DOC>
<DOC>
<DOCNO> 13047 </DOCNO>
Superconductivity with the Meron-Cluster Algorithm


  The meron-cluster algorithm was previously used to extensively study the
physics associated with the spontaneous breaking of a discrete symmetry. We
recently discovered that a larger class of models with spontaneous breaking of
continuous symmetries can also be simulated using the meron-cluster algorithm.
Here we study one of these new models which belongs to the attractive Hubbard
model family. In particular we study the spontaneous breaking of the U(1)
fermion number symmetry in two dimensions and find clear evidence for a
Kosterlitz-Thouless transition to a superconducting phase.

</DOC>
<DOC>
<DOCNO> 116614 </DOCNO>
Disjoining Potential and Spreading of Thin Liquid Layers in the Diffuse


  The hydrodynamic phase field model is applied to the problem of film
spreading on a solid surface. The disjoining potential, responsible for
modification of the fluid properties near a three-phase contact line, is
computed from the solvability conditions of the density field equation with
appropriate boundary conditions imposed on the solid support. The equation
describing the motion of a spreading film are derived in the lubrication
approximation. In the case of quasi-equilibrium spreading, is shown that the
correct sharp-interface limit is obtained, and sample solutions are obtained by
numerical integration. It is further shown that evaporation or condensation may
strongly affect the dynamics near the contact line, and accounting for kinetic
retardation of the interphase transport is necessary to build up a consistent
theory.

</DOC>
<DOC>
<DOCNO> 39949 </DOCNO>
A study of the omega omega channel produced in central pp interactions


  The reaction pp -> pf (omega omega) ps has been studied at 450 GeV/c and a
spin analysis of the omega omega channel has been performed for the first time
in central production. Evidence is found for the f2(1910) in the JPC = 2++ wave
with spin projection JZ = 2. This is the only state observed in central
production with spin projection JZ = 2. Its dPT and phi dependencies are
similar to those observed for other glueball candidates. In addition, evidence
is found for a state with JPC = 4++ consistent with the f4(2300). The f0(2000),
previously observed in the rho rho final state, is confirmed.

</DOC>
<DOC>
<DOCNO> 7833 </DOCNO>
Clusters and Fluctuations at Mean-Field Critical Points and Spinodals


  We show that the structure of the fluctuations close to spinodals and
mean-field critical points is qualitatively different than the structure close
to non-mean-field critical points. This difference has important implications
for many areas including the formation of glasses in supercooled liquids. In
particular, the divergence of the measured static structure function in
near-mean-field systems close to the glass transition is suppressed relative to
the mean-field prediction in systems for which a spatial symmetry is broken.

</DOC>
<DOC>
<DOCNO> 120747 </DOCNO>
Gravitational lensing by elliptical galaxies


  The fraction of high-redshift sources which are multiply-imaged by
intervening galaxies is strongly dependent on the cosmological constant, and so
can be a useful probe of the cosmological model. However its power is limited
by various systematic (and random) uncertainties in the calculation of lensing
probabilities, one of the most important of which is the dynamical
normalisation of elliptical galaxies. Assuming ellipticals' mass distributions
can be modelled as isothermal spheres, the mass normalisation depends on: the
velocity anisotropy; the luminosity density; the core radius; and the area over
which the velocity dispersion is measured. The differences in the lensing
probability and optical depth produced by using the correct normalisation can
be comparable to the differences between even the most extreme cosmological
models. The existing data is not sufficient to determine the correct
normalisation with enough certainty to allow lensing statistics to be used to
their full potential. However, as the correct lensing probability is almost
certainly higher than is usually assumed, upper bounds on the cosmological
constant are not weakened by these possibilities.

</DOC>
<DOC>
<DOCNO> 11747 </DOCNO>
Mechanical Relaxation in Glasses and at the Glass Transition


  The Gilroy-Phillips model of relaxational jumps in asymmetric double-well
potentials, developed for the Arrhenius-type secondary relaxations of the glass
phase, is extended to a formal description of the breakdown of the shear
modulus at the glass transition, the flow process.

</DOC>
<DOC>
<DOCNO> 69140 </DOCNO>
What's new at small x


  We discuss some recent developments in small x physics.

</DOC>
<DOC>
<DOCNO> 70864 </DOCNO>
A Two-Dimensional Model with Chiral Condensates and Cooper Pairs Having


  We describe how a generalization of the original Gross-Neveu model from U(N)
to O(N) flavor symmetry leads to the appearance of a pairing condensate at high
density, in agreement with the conjectured phenomenon of color
superconductivity in $(3+1)$-dimensional QCD. Moreover, the model displays a
rich phase structure which closely resembles the one expected in two-flavor
QCD.

</DOC>
<DOC>
<DOCNO> 99627 </DOCNO>
Calibrated Fibrations on Complete Manifolds via Torus Action


  In this paper we will investigate torus actions on complete manifolds with
calibrations. For Calabi-Yau manifolds M^2n with a Hamiltonian
structure-preserving k-torus action we show that any symplectic reduction has a
natural holomorphic volume form. Moreover Special Lagrangian (SLag)
submanifolds of the reduction lift to SLag submanifolds of M, invariant under
the torus action. If k=n-1 and the first cohomology of M is trivial, then we
prove that M is a fibration with generic fiber being a SLag submanifold. As an
application we will see that crepant resolutions of singularities of a finite
Abelian subgroup of SU(n) acting on C^n have SLag fibrations. We study SLag
submanifolds on the total space K(N) of a canonical bundle of a Kahler-Einstein
manifold N with positive scalar curvature. We give a conjecture about fibration
of K(N) by SLag subvarieties with a certain asymptotic behavior at infinity,
which we prove if N is toric. We also get similar results for coassociative
submanifolds of a G_2-manifold M^7, which admits a 3-torus, a 2-torus or an
SO(3)-action.

</DOC>
<DOC>
<DOCNO> 13994 </DOCNO>
Comment on ''the controlled charge ordering and evidence of the metallic


  In a recent paper (2000 \QTR{it}{J. Phys.: Condens. Matter} \QTR{bf}{12}
L133) Lee \QTR{it}{et al.} have studied the transport properties of
Pr$_{0.65}$Ca$_{0.35}$MnO$_{3}$ thin films. They claimed that they are able to
controlled the charge-ordered (CO) state by the lattice strains. We propose
herein another alternative since another indexation of the orientation of the
film can be found leading to almost no distortion of the cell, as compared to
the bulk compound.

</DOC>
<DOC>
<DOCNO> 68197 </DOCNO>
Pion-nucleon scattering in chiral perturbation theory II: Fourth order


  We analyse elastic-pion nucleon scattering to fourth order in heavy baryon
chiral perturbation theory, extending the third order study published in Nucl.
Phys. A640 (1998) 199. We use various partial wave analyses to pin down the
low-energy constants from data in the physical region. The S-wave scattering
lengths are consistent with recent determinations from pionic hydrogen and
deuterium. We find an improved description of the P-waves. We also discuss the
pion-nucleon sigma term and problems related to the prediction of the
subthreshold parameters.

</DOC>
<DOC>
<DOCNO> 99746 </DOCNO>
Four-Manifolds which admit Z_p x Z_p actions


  We show that the simply-connected four-manifolds which admit locally linear,
homologically trivial actions by rank two finite abelian groups are
homeomorphic to connected sums of CP^2, -CP^2, and S^2 x S^2 (with one
exception: pseudofree Z_3 x Z_3 actions on the Chern manifold), and also
establish an equivariant decompostion theorem.
  This generalizes results from a 1970 paper by Orlik and Raymond, and
complements more recent work of Fintushel, Yoshida, and Huck on S^1 actions. In
each case, the simply-connected four-manifolds which support such actions are
essentially the same.

</DOC>
<DOC>
<DOCNO> 13023 </DOCNO>
Quantal Andreev billiards: Density of states oscillations and the


  Andreev billiards are finite, arbitrarily-shaped, normal-state regions,
surrounded by superconductor. At energies below the superconducting energy gap,
single-quasiparticle excitations are confined to the normal region and its
vicinity, the mechanism for confinement being Andreev reflection. Short-wave
quantal properties of these excitations, such as the connection between the
density of states and the geometrical shape of the billiard, are addressed via
a multiple scattering approach. It is shown that one can, inter alia, hear the
stationary chords of Andreev billiards.

</DOC>
<DOC>
<DOCNO> 118091 </DOCNO>
Extracting Energy from a Black Hole through Its Disk


  When some magnetic field lines connect a Kerr black hole with a disk rotating
around it, energy and angular momentum are transferred between them. If the
black hole rotates faster than the disk, $ca/GM_H>0.36$ for a thin Keplerian
disk, then energy and angular momentum are extracted from the black hole and
transferred to the disk ($M_H$ is the mass and $a M_H$ is the angular momentum
of the black hole). This way the energy originating in the black hole may be
radiated away by the disk.
  The total amount of energy that can be extracted from the black hole spun
down from $ca/GM_H = 0.998$ to $ca/GM_H = 0.36$ by a thin Keplerian disk is
$\approx 0.15 M_Hc^2$. This is larger than $\approx 0.09 M_Hc^2$ which can be
extracted by the Blandford-Znajek mechanism.

</DOC>
<DOC>
<DOCNO> 70756 </DOCNO>
Non-Perturbative Effects of Strong Magnetic Fields on Neutrino


  The Ritus' $E_{p}$ eigenfunction method is extended to the case of spin-1
charged particles in a constant electromagnetic field and used to calculate the
one-loop neutrino self-energy in the strong-field approximation $m_{e}^{2}\ll
eB\ll M_{W}^{2}$. The implications of the obtained results for neutrino
oscillations in the early Universe, assuming the existence of a sufficiently
large ($m_{e}^{2}\ll eB\ll m_{\mu}^{2}$) primordial magnetic field, are
discussed.

</DOC>
<DOC>
<DOCNO> 67801 </DOCNO>
Toward the non-perturbative description of high energy processes


  General implications of existence of non-perturbative scales and hadronic
sub-structure for high energy processes are discussed. We propose that the
dependence of the cross section of $\bar q q$ dipoles on their size d should
deviate from $d^2$ when d becomes comparable to substructure scale. Then we
discuss Kharzeev-Levin pomeron model \cite{KL}, based on ladder-type diagrams
with $scalar$ resonances (scalar $\pi\pi$ or $\sigma$ and the scalar glueball
$G_0$). This channel is truly unique, because instanton-induced attractive gg
interaction \cite{Shu_82} leads to unusually small sizes and strong coupling
constants of these states, supplemented by unusually large mass scale,
$M_0\approx 4 GeV$, of the transition boundary to the perturbative regime. As
pomeron is a small-size object by itself, these resonances may play a special
role in its dynamics. Furthermore, we use more realistic description of the
scalar gluonic spectral density without free parameters, and slightly modify
the model to get correct chiral limit. We conclude that the non-perturbative
part of the scalar contribution to the soft pomeron intercept is $\Delta =
>.05\pm 0.015$, with comparable contributions from both $\sigma$ and $G_0$.

</DOC>
<DOC>
<DOCNO> 10798 </DOCNO>
Exactly solvable model with two conductor-insulator transitions driven


  We present an exact analysis of two conductor-insulator transitions in the
random graph model. The average connectivity is related to the concentration of
impurities. The adjacency matrix of a large random graph is used as a hopping
Hamiltonian. Its spectrum has a delta peak at zero energy. Our analysis is
based on an explicit expression for the height of this peak, and a detailed
description of the localized eigenvectors and of their contribution to the
peak. Starting from the low connectivity (high impurity density) regime, one
encounters an insulator-conductor transition for average connectivity
1.421529... and a conductor-insulator transition for average connectivity
3.154985.... We explain the spectral singularity at average connectivity
e=2.718281... and relate it to another enumerative problem in random graph
theory, the minimal vertex cover problem.

</DOC>
<DOC>
<DOCNO> 11602 </DOCNO>
Chern-Simons versus dipolar composite fermions at finite wavevector


  It was recently shown that dipolar composite fermions emerged from the
lowest-Landau-level formulation of the quantum Hall effect give rise to similar
results as those of the Chern-Simons gauge theory in the long wavelength and
low energy limit. We ask whether this correspondence is still valid at finite
wavevectors where the excitations do not necessarily look like dipolar
quasiparticles. In particular, q=2k_F density-density response function of the
compressible state at \nu=1/2 is evaluated in the low energy limit within the
framework of the lowest-Landau-level theory. The imaginary parts of the
density-density response functions at q=2k_F of two theories have the same
\sqrt{\omega} dependence. However, the coefficient of the \sqrt{\omega} term in
the case of the lowest-Landau-level theory is not universal and can be much
smaller than the corresponding coefficient in the Chern-Simons theory. We also
discuss possible connection between these results and the recent experiment on
phonon-mediated drag in the double-layer \nu=1/2 system.

</DOC>
<DOC>
<DOCNO> 174469 </DOCNO>
Probing the 6He halo structure with elastic and inelastic proton


  Proton elastic scattering and inelastic scattering to the first excited state
of 6He have been measured over a wide angular range using a 40.9A MeV 6He beam.
The data have been analyzed with a fully microscopic model of proton-nucleus
scattering using 6He wave functions generated from large space shell model
calculations. The inelastic scattering data show a remarkable sensitivity to
the halo structure of 6He.

</DOC>
<DOC>
<DOCNO> 14161 </DOCNO>
High Temperature Expansion for a Chain Model


  We consider an arbitrary translationally invariant chain model with nearest
neighbors interaction and satisfying periodic boundary condition.
 The approach developed here allows a thermodynamic description of the chain
model directly in terms of grand potential per site. This thermodynamic
function is derived from an auxiliary function constructed only from open
connected sub-chains. In order to exemplify its application and how this
approach works we consider the Heisenberg XXZ model. We obtain the coefficients
of the high temperature expansion of the free energy per site of the model up
to third order.

</DOC>
<DOC>
<DOCNO> 120274 </DOCNO>
Optimizing the angular resolution of the HEGRA telescope system to study


  The HEGRA system of imaging atmospheric Cherenkov telescopes provides for
specially selected classes of events an angular resolution of better than 3'.
By comparing the measured angular distribution of TeV gamma rays from the Crab
Nebula with the distribution expected on the basis of Monte Carlo simulations,
and with measurements of gamma rays from the point source Mrk 501, we conclude
that the rms size of the VHE gamma-ray emission region in the Crab Nebula is
less than 1.5'.

</DOC>
<DOC>
<DOCNO> 123030 </DOCNO>
Helium-like triplet density diagnostics: Applications to CHANDRA--LETGS


  Electron density diagnostics based on the triplets of Helium-like CV, NVI,
and OVII are applied to the X-ray spectra of Capella and Procyon measured with
the Low Energy Transmission Grating Spectrometer (LETGS) on board the Chandra
X-ray Observatory. New theoretical models for the calculation of the line
ratios between the forbidden (f), intercombination (i), and the resonance (r)
lines of the helium-like triplets are used. The derived densities are quite
typical of densities found in the solar active regions, and also pressures and
temperatures in Procyon's and Capella's corona at a level of T=10^6K are quite
similar. We find no evidence for densities as high as measured in solar flares.
Comparison of our Capella and Procyon measurements with the Sun shows little
difference in the physical properties of the layers producing the CV, NVI, and
OVII emission. Assuming the X-ray emitting plasma to be confined in magnetic
loops, we obtain typical loop length scales of L_Capella > 8 L_Procyon from the
loop scaling laws, implying that the magnetic structures in Procyon and Capella
are quite different. The total mean surface fluxes emitted in the helium- and
hydrogen-like ions are quite similar for Capella and Procyon, but exceed
typical solar values by one order of magnitude. We thus conclude that Procyon's
and Capella's coronal filling factors are larger than corresponding solar
values.

</DOC>
<DOC>
<DOCNO> 117822 </DOCNO>
Molecules as Tracers of PN Structure


  Molecular gas plays an important role in the structure of planetary nebulae:
it is a major component of the equatorial tori of bipolar nebulae, it forms the
cores of globules and related mircostructures, and is the likely origin of
multiple arcs. It is also a key component during the early stages of formation
where interactions with outflows or jets provide an important shaping
mechanism.

</DOC>
<DOC>
<DOCNO> 170232 </DOCNO>
No contradictions between Bohmian and quantum mechanics


  Two recent claims by A. Neumaier (quant-ph/0001011) and P. Ghose
(quant-ph/0001024) that Bohmian mechanics is incompatible with quantum
mechanics for correlations involving time are shown to be unfounded.

</DOC>
<DOC>
<DOCNO> 40230 </DOCNO>
Role of the Delta (1232) in DIS on polarized $^3$He and extraction of


  We consider the effect of the transitions $n \to \Delta^{0}$ and $p \to
\Delta^{+}$ in deep inelastic scattering on polarized $^3$He on the extraction
of the neutron spin structure function $g_{1}^{n}(x,Q^2)$. Making the natural
assumption that these transitions are the dominant non-nucleonic contributions
to the renormalization of the axial vector coupling constant in the A=3 system,
we find that the effect of $\Delta$ increases $g_{1}^{n}(x,Q^2)$ by $10 \div
40$% in the range $0.05 \le x \le 0.6$, where our considerations are applicable
and most of the data for $g_{1}^{n}(x,Q^2)$ exist.

</DOC>
<DOC>
<DOCNO> 117468 </DOCNO>
Comparing the Evolution of the Galaxy Disk Sizes with CDM Models: The


  The intrinsic sizes of the field galaxies with I<26 in the Hubble and ESO-NTT
Deep Fields are shown as a function of their redshifts and absolute magnitudes
using photometric redshifts derived from the multicolor catalogs and are
compared with the CDM predictions. Extending to lower luminosities and to
higher z our previous analysis performed on the NTT field alone, we find that
the distribution of the galaxy disk sizes at different cosmic epochs is within
the range predicted by typical CDM models. However, the observed size
distribution of faint (M_B>-19) galaxies is skewed with respect to the CDM
predictions and an excess of small-size disks (R_d<2 kpc) is already present at
z~ 0.5. The excess persists up to z~3 and involves brighter galaxies . Such an
excess may be reduced if luminosity-dependent effects, like starburst activity
in interacting galaxies, are included in the physical mechanisms governing the
star formation history in CDM models.

</DOC>
<DOC>
<DOCNO> 122106 </DOCNO>
SPIRAL Phase A: A Prototype Integral Field Spectrograph for the AAT


  We present details of a prototype fiber feed for use on the Anglo-Australian
Telescope (AAT) that uses a dedicated fiber-fed medium/high resolution (R >
10000) visible-band spectrograph to give integral field spectroscopy (IFS) of
an extended object. A focal reducer couples light from the telescope to the
close-packed lenslet array and fiber feed, allowing the spectrograph be used on
other telescopes with the change of a single lens. By considering the
properties of the fibers in the design of the spectrograph, an efficient design
can be realised, and we present the first scientific results of a prototype
spectrograph using a fiber feed with 37 spatial elements, namely the detection
of Lithium confirming a brown dwarf candidate and IFS of the supernova remnant
SN1987A.

</DOC>
<DOC>
<DOCNO> 102258 </DOCNO>
Quantum Jacobi fields in Hamiltonian mechanics


  Jacobi fields of classical solutions of a Hamiltonian mechanical system are
quantized in the framework of vertical-extended Hamiltonian formalism. Quantum
Jacobi fields characterize quantum transitions between classical solutions.

</DOC>
<DOC>
<DOCNO> 102342 </DOCNO>
Classification of simple $C^*$-algebras of tracial topological rank zero


  We give a classification theorem for unital separable simple nuclear
$C^*$-algebras with tracial topological rank zero which satisfy the Universal
Coefficient Theorem. We prove that if $A$ and $B$ are two such $C^*$-algebras
and $$ (K_0(A), K_0(A)_+, [1_A], K_1(A)) $$ $$ \cong (K_0(B), K_0(B)_+, [1_B],
K_1(B)), $$ then $A\cong B.$

</DOC>
<DOC>
<DOCNO> 118689 </DOCNO>
Type Ia Supernovae


  Type Ia Supernovae are in many aspects still enigmatic objects. Recent years
have witnessed a bonanza of supernova observations. The increased samples from
dedicated searches have allowed the statistical investigation of Type Ia
Supernovae as a class. The observational data on Type Ia Supernovae are very
rich, and the uniform picture of a decade ago has been replaced by several
correlations which connect the maximum luminosity with light curve shape, color
evolution, spectral appearance, and host galaxy morphology. These correlations
hold across almost the complete spectrum of Type Ia Supernovae, with a number
of notable exceptions. After 150 days past maximum, however, all observed
objects show the same decline rate and spectrum. Bolometric light curves are a
handy tool to investigate the overall appearance of Type Ia Supernovae. The
nickel masses derived this way show large variations, which combined with the
dynamics from line widths, indicate that the brighter events are also coming
from more massive objects. The lack of accurate distances and the uncertainty
in the correction for absorption are hampering further progress. Improvements
in these areas are vital for the detailed comparison of luminosities and the
determination of nickel masses.

</DOC>
<DOC>
<DOCNO> 8250 </DOCNO>
Casimir Dispersion Forces and Orientational Pairwise Additivity


  A path integral formulation is used to study the fluctuation-induced
interactions between manifolds of arbitrary shape at large separations. It is
shown that the form of the interactions crucially depends on the choice of the
boundary condition. In particular, whether or not the Casimir interaction is
pairwise additive is shown to depend on whether the ``metallic'' boundary
condition corresponds to a ``grounded'' or an ``isolated'' manifold.

</DOC>
<DOC>
<DOCNO> 11003 </DOCNO>
Superexchange and lattice distortions in the spin--Peierls system CuGeO3


  We present a study of the nearest--neighbor (nn) and next-nearest-neighbor
(nnn) exchange constants between magnetic Cu centers of the spin-Peierls
material CuGeO3. The dependence of these constants on the lattice parameters
(modified e.g. by variation of temperature, pressure or doping) is calculated.
Based on the observation that the bond angles are more susceptible than the
bond lengths we propose the so-called ''accordion'' model for the description
of the properties of CuGeO3. We show that the nn exchange constant in the CuO2
ribbon is very sensitive to the presence and position of the side group Ge with
respect to this ribbon. The angle between the two basic units the CuO2 ribbon
and the GeO3 zig-zag chain is, besides the Cu-O-Cu angle in the ribbon, one of
the principal lattice parameters determining the nn exchange in the c
direction. The microscopic calculations of different exchange constants and
their dependence on the lattice parameters are carried out using different
schemes (perturbation theory; exact diagonalization of Cu2O2 clusters; band
approach). The results compare favorable with experiment. The influence of Si
doping is also calculated, and the reasons of why it is so efficient in
suppressing the spin-Peierls phase are discussed. Thus the consistent
microscopic picture of the properties of CuGeO3 emerges.

</DOC>
<DOC>
<DOCNO> 8874 </DOCNO>
Steady-states and kinetics of ordering in bus-route models: connection


  A Bus Route Model (BRM) can be defined on a one-dimensional lattice, where
buses are represented by "particles" that are driven forward from one site to
the next with each site representing a bus stop. We replace the random
sequential updating rules in an earlier BRM by parallel updating rules. In
order to elucidate the connection between the BRM with parallel updating
(BRMPU) and the Nagel-Schreckenberg (NaSch) model, we propose two alternative
extensions of the NaSch model with space-/time-dependent hopping rates.
Approximating the BRMPU as a generalization of the NaSch model, we calculate
analytically the steady-state distribution of the {\it time headways} (TH)
which are defined as the time intervals between the departures (or arrivals) of
two successive particles (i.e., buses) recorded by a detector placed at a fixed
site (i.e., bus stop) on the model route. We compare these TH distributions
with the corresponding results of our computer simulations of the BRMPU, as
well as with the data from the simulation of the two extended NaSch models. We
also investigate interesting kinetic properties exhibited by the BRMPU during
its time evolution from random initial states towards its steady-states.

</DOC>
<DOC>
<DOCNO> 121609 </DOCNO>
Protoneutron Stars with Kaon Condensation and their Delayed Collapse


  Properties of protoneutron stars are discussed in the context of kaon
condensation. Thermal and neutrino trapping effects are very important
ingredients to study them. By solving the TOV equation, we discuss the static
properties of protoneutron stars and the possibility of the delayed collapse
during their evolution.

</DOC>
<DOC>
<DOCNO> 102353 </DOCNO>
Central Simple Poisson Algebras


  In this paper, we determine the isomorphism classes of the central simple
Poisson algebras introduced earlier by the second author. The Lie algebra
structures of these Poisson algebras are in general not finitely-graded.

</DOC>
<DOC>
<DOCNO> 80707 </DOCNO>
Massive random matrix ensembles at beta = 1 & 4 : QCD in three


  The zero momentum sectors in effective theories of three dimensional QCD
coupled to pseudoreal (two colors) and real (adjoint) quarks in a classically
parity-invariant manner have alternative descriptions in terms of orthogonal
and symplectic ensembles of random matrices. Using this correspondence, we
compute finite-volume QCD partition functions and correlation functions of
Dirac operator eigenvalues in a presence of finite quark masses of the order of
the smallest Dirac eigenvalue. These novel correlation functions, expressed in
terms of quaternion determinants, are reduced to conventional results for the
Gaussian ensembles in the quenched limit.

</DOC>
<DOC>
<DOCNO> 8262 </DOCNO>
Thermal expansion in small metal clusters and its impact on the electric


  The thermal expansion coefficients of $\mathrm{Na}_{N}$ clusters with $8 \le
N \le 40$ and $\mathrm{Al}_{7}$, $\mathrm{Al}_{13}^-$ and $\mathrm{Al}_{14}^-$
are obtained from {\it ab initio} Born-Oppenheimer LDA molecular dynamics.
Thermal expansion of small metal clusters is considerably larger than that in
the bulk and size-dependent. We demonstrate that the average static electric
dipole polarizability of Na clusters depends linearly on the mean interatomic
distance and only to a minor extent on the detailed ionic configuration when
the overall shape of the electron density is enforced by electronic shell
effects. The polarizability is thus a sensitive indicator for thermal
expansion. We show that taking this effect into account brings theoretical and
experimental polarizabilities into quantitative agreement.

</DOC>
<DOC>
<DOCNO> 9468 </DOCNO>
Reversible Boolean Networks I: Distribution of Cycle Lengths


  We consider a class of models describing the dynamics of $N$ Boolean
variables, where the time evolution of each depends on the values of $K$ of the
other variables. Previous work has considered models with dissipative dynamics.
Here we consider time-reversible models, which necessarily have the property
that every possible point in the state-space is an element of one and only one
cycle.
  As in the dissipative case, when K is large, typical orbit lengths grow
exponentially with N, whereas for small enough K, typical orbit lengths grow
much more slowly with N. The numerical data are consistent with the existence
of a phase transition at which the average orbit length grows as a power of N
at a value of K between 1.4 and 1.7. However, in the reversible models the
interplay between the discrete symmetry and quenched randomness can lead to
enormous fluctuations of orbit lengths and other interesting features that are
unique to the reversible case.
  The orbits can be classified by their behavior under time reversal. The
orbits that transform into themselves under time reversal have properties quite
different from those that do not; in particular, a significant fraction of
latter-type orbits have lengths enormously longer than orbits that are time
reversal-symmetric. For large K and moderate N, the vast majority of points in
the state-space are on one of the time reversal singlet orbits, and a random
hopping model gives an accurate description of orbit lengths. However, for any
finite K, the random hopping approximation fails qualitatively when N is large
enough ($N\gg 2^{(2^K)}$).

</DOC>
<DOC>
<DOCNO> 11607 </DOCNO>
The Josephson critical current in a long mesoscopic S-N-S junction


  We carry out an extensive experimental and theoretical study of the Josephson
effect in S-N-S junctions made of a diffusive normal metal (N) embedded between
two superconducting electrodes (S). Our experiments are performed on Nb-Cu-Nb
junctions with highly-transparent interfaces. We give the predictions of the
quasiclassical theory in various regimes on a precise and quantitative level.
We describe the crossover between the short and the long junction regimes and
provide the temperature dependence of the critical current using dimensionless
units $eR_{N}I_{c}/\epsilon_{c}$ and $k_{B}T/\epsilon_{c}$ where $\epsilon_{c}$
is the Thouless energy. Experimental and theoretical results are in excellent
quantitative agreement.

</DOC>
<DOC>
<DOCNO> 84968 </DOCNO>
Inferences from the dark sky: Olbers' paradox revisited


  The classical formulation of "Olbers' Paradox" consists in looking for an
explanation of the fact that the sky at night is dark. We use the experimental
datum of the nocturnal darkness in order to put constraints on a newtonian
cosmological model. We infer then that the Universe should have had an origin
in the past.

</DOC>
<DOC>
<DOCNO> 70557 </DOCNO>
Low Energy Solar Neutrino Detection by using Liquid Xenon


  Possibility to use ultra pure liquid Xenon as a low energy solar neutrino
detector by means of $\nu$+e scatterings is evaluated. A possible detector with
10 tons of fiducial volume will give $\sim$14 events for pp-neutrinos and
$\sim$6 events for $^{7}$Be neutrinos with the energy threshold at 50 keV. The
detector can be built with known and established technologies. High density of
the liquid- Xe would provide self-shields against the incoming backgrounds
originating from the container and outer environments. Internal backgrounds can
be reduced by distillation and other techniques. Purification of the liquid Xe
can be done continuously throughout the experiment. The spallation backgrounds
are estimated to be small though an experimental determination is neccessary.
The liquid-Xe detector can also provide a significantly better sensitivity for
the double beta decay and a dark matter search. However the 2$\nu$ double beta
decay of $^{136}$Xe would be most background. It could be overcome if the
2$\nu$ lifetime is longer than 10$^{22}$yr. However, an isotope separation of
$^{136}$Xe is inevitable for a shorter lifetime.
  The isotope separations would, intoroduce a new opportunity to definitively
identify dark matter. The interesting feature in addition to the solar neutrino
measurements will also be discussed.

</DOC>
<DOC>
<DOCNO> 70959 </DOCNO>
On the short distance nonperturbative corrections in heavy quark


  We estimate the renormalon corrections to the inclusive decay rate of heavy
hadrons. We assume the gluon mass term $\lambda^2 \gg `^2$ to imitate the short
distance nonperturbative effects. It is found that the the inclusive decay
rates are corrected by an amount of about 0.2 $\Gamma_0$ for $B$ meson and 0.21
$\Gamma_0$ for baryon. This is significant in view of the discrepancy of
lifetimes of $B$ and $\lbb$.

</DOC>
<DOC>
<DOCNO> 99720 </DOCNO>
On Ramond-Ramond fields and K-theory


  A recent paper by Moore and Witten explained that Ramond-Ramond fields in
Type II superstring theory have a global meaning in K-theory. In this note we
amplify and generalize some points raised in that paper. In particular, we
express the coupling of the Ramond-Ramond fields to D-branes in a K-theoretic
framework and show that the anomaly in this coupling exactly cancels the
anomaly from the fermions on the brane, both in Type IIA and Type IIB.

</DOC>
<DOC>
<DOCNO> 11951 </DOCNO>
Thermodynamic Capacity of a Protein


  We show that a protein can be trained to recognise multiple conformations,
analogous to an associative memory, and provide capacity calculations based on
energy fluctuations and information theory. Unlike the linear capacity of a
Hopfield network, the number of conformations which can be remembered by a
protein sequence depends on the size of the amino acid alphabet as ln A,
independent of protein length. This admits the possibility of certain proteins,
such as prions, evolving to fold to independent stable conformations, as well
as novel possibilities for protein and heteropolymer design.

</DOC>
<DOC>
<DOCNO> 100526 </DOCNO>
Moduli, Motives, Mirrors (Plenary talk at the 3rd ECM, Barcelona, July


  This talk is dedicated to various aspects of Mirror Symmetry. It summarizes
some of the mathematical developments that took place since M. Kontsevich's
report at the Z\"urich ICM and provides an extensive, although not exhaustive,
bibliography.

</DOC>
<DOC>
<DOCNO> 71067 </DOCNO>
Running couplings in extra dimensions


  The regularization scheme dependence of running couplings in extra
compactified dimensions is discussed. We examine several regularization schemes
explicitly in order to analyze the scheme dependence of the Kaluza-Klein
threshold effects, which cause the power law running, in the case of the scalar
theory in five dimensions with one dimension compactified. It is found that in
1-loop order, the net difference in the running of the coupling among the
different schemes is reduced to be rather small after finite renormalization.
An additional comment concerns the running couplings in the warped extra
dimensions which are found to be regularization dependent above TeV scale.

</DOC>
<DOC>
<DOCNO> 102778 </DOCNO>
Invitation to higher local fields, Part I, section 13: Abelian


  This is an introduction to the author theory of cyclic p-extensions of an
absolutely unramified complete discrete valuation field K with arbitrary
residue field of characteristic p. In this theory a homomorphism is constructed
from the p-part of the group of characters of K to Witt vectors over its
residue field.

</DOC>
<DOC>
<DOCNO> 102891 </DOCNO>
On the orientation of graphs


  In this short notice we give a universal definition of $\Z_2$-module
$Or(\Gamma)$ of orientations of a graph $\Gamma$ and construct a method, by
means of which one can easily verify whenever two such special definitions
coincide.

</DOC>
<DOC>
<DOCNO> 100205 </DOCNO>
Actions of semisimple Lie groups on circle bundles


  Suppose G is a connected, simple, real Lie group with real rank at least two,
M is an ergodic G-space with invariant probability measure, and f is a
Homeo(T)-valued Borel cocycle, where Homeo(T) denotes the group of
homeomorphisms of the circle T. We use an argument of E.Ghys to show that there
is a G-invariant probability measure on the skew product of M and T.
Furthermore, if the image of f consists of diffeomorphisms, then there is an
invariant measure that is equivalent to the product measure; therefore, f is
cohomologous to a cocycle with values in the isometry group of T.

</DOC>
<DOC>
<DOCNO> 151652 </DOCNO>
Supersymmetric phases of finite-temperature strings II


  It was recently proposed that there exist stable supersymmetric phases for
finite temperature superstings. This issue was investigated using an effective
supergravity which takes into account massive winding modes. Such a theory
admits BPS solutions that do not suffer from Hagedorn-type instabilities. We
extend several aspects of this work. First we restrict to the real-field sector
of the theory and allow, in general, for unequal right and left winding fields.
Then, by further specializing to type-II theories (IIA, IIB and a self-dual
hybrid) we construct the most general 1/2-BPS solution and reveal several new
features arising in various consistent truncations. In the heterotic case we
investigate the general properties of the solution which is presented in a
closed form in the limit of infinitely large left-winding field.

</DOC>
<DOC>
<DOCNO> 12836 </DOCNO>
On the Rapid Estimation of Permeability for Porous Media Using Brownian


  We describe two efficient methods of estimating the fluid permeability of
standard models of porous media by using the statistics of continuous Brownian
motion paths that initiate outside a sample and terminate on contacting the
porous sample. The first method associates the "penetration depth" with a
specific property of the Brownian paths, then uses the standard relation
between penetration depth and permeability to calculate the latter. The second
method uses Brownian paths to calculate an effective capacitance for the
sample, then relates the capacitance, via angle-averaging theorems to the
translational hydrodynamic friction of the sample. Finally, a result of
Felderhof is used to relate the latter quantity to the permeability of the
sample. We find that the penetration depth method is highly accurate in
predicting permeability of porous material.

</DOC>
<DOC>
<DOCNO> 39646 </DOCNO>
QCD Analyses and determinations of alpha-s in e+e- Annihilation at


  We employ data taken by the JADE and OPAL experiments for an integrated QCD
study in hadronic e+e- annihilations at c.m.s. energies ranging from 35 GeV
through 189 GeV. The study is based on jet-multiplicity related observables.
The observables are obtained to high jet resolution scales with the JADE,
Durham, Cambridge and cone jet finders, and compared with the predictions of
various QCD and Monte Carlo models. The strong coupling strength, alpha_s, is
determined at each energy by fits of O(alpha_s^2) calculations, as well as
matched O(alpha_s^2) and NLLA predictions, to the data. Matching schemes are
compared, and the dependence of the results on the choice of the
renormalization scale is investigated. The combination of the results using
matched predictions gives alpha_s(MZ)=0.1187+{0.0034}-{0.0019}. The strong
coupling is also obtained, at lower precision, from O(alpha_s^2) fits of the
c.m.s. energy evolution of some of the observables. A qualitative comparison is
made between the data and a recent MLLA prediction for mean jet multiplicities.

</DOC>
<DOC>
<DOCNO> 85372 </DOCNO>
An efficient filter for detecting gravitational wave bursts in


  Typical sources of gravitational wave bursts are supernovae, for which no
accurate models exist. This calls for search methods with high efficiency and
robustness to be used in the data analysis of foreseen interferometric
detectors. A set of such filters is designed to detect gravitational wave burst
signals. We first present filters based on the linear fit of whitened data to
short straight lines in a given time window and combine them in a non linear
filter named ALF. We study the performances and efficiencies of these filters,
with the help of a catalogue of simulated supernova signals.
  The ALF filter is the most performant and most efficient of all filters. Its
performance reaches about 80% of the Optimal Filter performance designed for
the same signals. Such a filter could be implemented as an online trigger
(dedicated to detect bursts of unknown waveform) in interferometric detectors
of gravitational waves.

</DOC>
<DOC>
<DOCNO> 14086 </DOCNO>
NQR of barium in BaBiO3 and BaPbO3


  The NQR on Ba nuclei was studied in four samples of BaBiO3 prepared in
different ways and, in addition, in BaPbO3. The spectrum of $^{137}$Ba at T=4.2
K consists of relatively broad line centered near 18 MHz for all BaBiO3 samples
and near 13 MHz for BaPbO3. The integrated intensity of $^{137}$Ba resonance in
ceramic sample BaBiO3 synthesized at 800 C is approximately two times larger
than in ceramic samples and single crystal prepared at 930-1080 C. The decrease
of the NQR signal can be attributed to the partial disordering of charge
disproportionated Bi ions on the two inequivalent sites. The broadening of the
resonance indicates that local distortions of crystal structure exist in both
compounds. The point charge model was used to analyse the electric field
gradient on the Ba sites

</DOC>
<DOC>
<DOCNO> 119320 </DOCNO>
Merging neutron stars: asymmetric systems


  Results of 3D, Newtonian hydrodynamic calculations of the last stages of the
inspiral and the final coalescence of neutron star binary systems are
described. The focus is on sligthly asymmetric systems with the asymmetry
stemming either from different spins or different masses of the binary
components. Implications for nucleosynthesis and gamma ray bursts are
discussed. Test calculations for the used viscosity scheme are provided in the
appendix.

</DOC>
<DOC>
<DOCNO> 178703 </DOCNO>
Correlated model for quasi-elastic responses in finite nuclear systems


  A model to calculate nuclear responses considering short-range correlation
effects is presented. The model is applied to the study of electromagnetic
responses induced by one-body operators. We calculate one- and two-nucleon
emission responses and cross sections of the 16O and 40Ca nuclei in the
quasi-elastic region, and we compare them with experimental data.

</DOC>
<DOC>
<DOCNO> 13762 </DOCNO>
Sharp interface limit of a phase-field model of crystal grains


  We analyze a two-dimensional phase field model designed to describe the
dynamics of crystalline grains. The phenomenological free energy is a
functional of two order parameters. The first one reflects the orientational
order while the second reflects the predominant local orientation of the
crystal. We consider the gradient flow of this free energy. Solutions can be
interpreted as ensembles of grains (in which the phase of the order parameter
is approximately constant in space) separated by grain boundaries. We study the
dynamics of the boundaries as well as the rotation of the grains. In the limit
of the infinitely sharp interface, the normal velocity of the boundary is
proportional to both its curvature and its energy. We obtain explicit formulas
for the interfacial energy and mobility and study their behavior in the limit
of a small misorientation. We calculate the rate of rotation of a grain in the
sharp interface limit and find that it depends sensitively on the choice of the
model.

</DOC>
<DOC>
<DOCNO> 72168 </DOCNO>
Semileptonic B Decays into Excited Charmed Mesons ($D_1$, $D^*_2$) in


  Exclusive semileptonic B decays into excited charmed mesons ($D_1$, $D^*_2$)
are studied up to the order of $1/m_Q$ in the framework of the heavy quark
effective field theory (HQEFT), which contains the contributions of both
particles and antiparticles. Two wave functions $\eta^b_0$ and $\eta^c_0$,
which characterize the contributions from the kinematic operator at the order
of $1/m_Q$, are calculated by using QCD sum rule approach in HQEFT. Zero recoil
values of other two wave functions $\kappa'_1$ and $\kappa'_2$ are extracted
from the excited charmed-meson masses. Possible effects from the spin-dependent
transition wave functions which arise from the magnetic operators at the order
of $1/m_Q$ are analyzed. It is shown that the experimental measurements for the
branching ratios of $B \to D_1 l\nu$ and $B \to D^*_2 l\nu$ can be understood
in the framework of HQEFT.

</DOC>
<DOC>
<DOCNO> 12905 </DOCNO>
Metal-insulator transitions in anisotropic 2d systems


  Several phenomena related to the critical behaviour of non-interacting
electrons in a disordered 2d tight-binding system with a magnetic field are
studied. Localization lengths, critical exponents and density of states are
computed using transfer matrix techniques. Scaling functions of isotropic
systems are recovered once the dimension of the system in each direction is
chosen proportional to the localization length. It is also found that the
critical point is independent of the propagation direction, and that the
critical exponents for the localization length for both propagating directions
are equal to that of the isotropic system (approximately 7/3). We also
calculate the critical value of the scaling function for both the isotropic and
the anisotropic system. It is found that the isotropic value equals the
geometric mean of the two anisotropic values. Detailed numerical studies of the
density of states for the isotropic system reveals that for an appreciable
amount of disorder the critical energy is off the band center.

</DOC>
<DOC>
<DOCNO> 170692 </DOCNO>
A geometrical approach to non-adiabatic transitions in quantum theory:


  This article deals with non-adiabatic processes (i.e. processes excluded by
the adiabatic theorem) from the geometrical (group-theoretical) point of view.
An approximated formula for the probabilities of the non-adiabatic transitions
is derived in the adiabatic regime for the case when the parameter-dependent
Hamiltonian represents a smooth curve in the Lie algebra and the quantal
dynamics is determined by the corresponding Lie group evolution operator. We
treat the spin precession in a time-dependent magnetic field and the
over-barrier reflection problem in a uniform way using the first-order
dynamical equations on SU(2) and $SU(1.1)$ group manifolds correspondingly.
  A comparison with analytic solutions for simple solvable models is provided.

</DOC>
<DOC>
<DOCNO> 101261 </DOCNO>
An analogue of minimal surface theory in SL(n,C)/SU(n)


  We shall discuss the class of surfaces with holomorphic right Gauss maps in
non-compact duals of compact semisimple Lie groups (e.g. SL(n,C)/SU(n)), which
contains minimal surfaces in R^n and constant mean curvature 1 surfaces in H^3.
A Weierstrass type representation formula, and a Chern-Osserman type inequality
for such surfaces are given.

</DOC>
<DOC>
<DOCNO> 100014 </DOCNO>
On the WDVV-equation in quantum K-theory


  A K-theoretic counterpart of quantum cohomology theory is discussed.

</DOC>
<DOC>
<DOCNO> 83438 </DOCNO>
Collecting Graphical Abstract Views of Mercury Program Executions


  A program execution monitor is a program that collects and abstracts
information about program executions. The "collect" operator is a high level,
general purpose primitive which lets users implement their own monitors.
"Collect" is built on top of the Mercury trace. In previous work, we have
demonstrated how this operator can be used to efficiently collect various kinds
of statistics about Mercury program executions. In this article we further
demonstrate the expressive power and effectiveness of "collect" by providing
more monitor examples. In particular, we show how to implement monitors that
generate graphical abstractions of program executions such as proof trees,
control flow graphs and dynamic call graphs. We show how those abstractions can
be easily modified and adapted, since those monitors only require several
dozens of lines of code. Those abstractions are intended to serve as front-ends
of software visualization tools. Although "collect" is currently implemented on
top of the Mercury trace, none of its underlying concepts depend of Mercury and
it can be implemented on top of any tracer for any programming language.

</DOC>
<DOC>
<DOCNO> 118479 </DOCNO>
Lopsided Galaxies, Weak Interactions and Boosting the Star Formation


  To investigate the link between weak tidal interactions in disk galaxies and
the boosting of their recent star formation, we obtain images and spatially
integrated spectra (3615A < lambda < 5315A) for 40 late-type spiral galaxies
(Sab-Sbc) with varying degrees of lopsidedness (a dynamical indicator of weak
interactions). We quantify lopsidedness as the amplitude <A_1> of the m=1
Fourier component of the azimuthal surface brightness distribution, averaged
over a range of radii. We compare the young stellar content, quantified by
EW(H\delta_abs) and the strength of the 4000 Angstrom break (D_4000), with
lopsidedness and find a 3-4 sigma correlation between the two. We also find a
3.2 sigma correlation between EW(H\beta_emission) and lopsidedness. Using the
evolutionary population synthesis code of Bruzual & Charlot we model the
spectra as an ``underlying population'' and a superimposed ``boost population''
with the aim of constraining the fractional boost in the SFR averaged over the
past 0.5 Gyr (the characteristic lifetime of lopsidedness). From the difference
in both EW(H\delta_abs) and D_4000 between the most and least symmetric thirds
of our sample, we infer that ~ 1x10^9 M_solar of stars are formed over the
duration of a lopsided event in addition to the ``underlying'' SFH (assuming a
final galactic stellar mass of 10^10 M_solar). This corresponds to a factor of
8 increase in the SFR over the past 5x10^8 years. For the nuclear spectra, all
of the above correlations except D_4000 vs. <A_1> are weaker than for the disk,
indicating that in lopsided galaxies, the SF boost is not dominated by the
nucleus.

</DOC>
<DOC>
<DOCNO> 150562 </DOCNO>
Chaotic behavior in a Z_2 x Z_2 field theory


  We investigate the presence of chaos in a system of two real scalar fields
with discrete Z_2 x Z_2 symmetry. The potential that identify the system is
defined with a real parameter r and presents distinct features for r>0 and for
r<0. For static field configurations, the system supports two topological
sectors for r>0, and only one for r<0. Under the assumption of spatially
homogeneous fields, the system exhibts chaotic behavior almost everywhere in
parameter space. In particular a more complex dynamics appears for r>0; in this
case chaos can decrease for increasing energy, a fact that is absent for r<0.

</DOC>
<DOC>
<DOCNO> 101220 </DOCNO>
Permutations avoiding a pattern from $S_k$ and at least two patterns


  In this paper, we find explicit formulas or generating functions for the
cardinalities of the sets $S_n(T,\tau)$ of all permutations in $S_n$ that avoid
a pattern $\tau\in S_k$ and a set $T$, $|T|\geq 2$, of patterns from $S_3$. The
main body of the paper is divided into three sections corresponding to the
cases $|T|=2,3$ and $|T|\geq 4$. As an example, in the fifth section, we obtain
the complete classification of all cardinalities of the sets $S_n(T,\tau)$ for
$k=4$.

</DOC>
<DOC>
<DOCNO> 123250 </DOCNO>
The O-Na and Mg-Al Anticorrelations in Turn-Off and early Subgiants in


  High dispersion spectra (R>40,000) for a quite large number of stars at the
main sequence turn-off and at the base of the subgiant branch in NGC6397 and
NGC6752 were obtained with the UVES on Kueyen (VLT UT2). The [Fe/H] values we
found are -2.03+/-0.02+/-0.04 and -1.42+/-0.02+/-0.04 for NGC6397 and NGC6752
respectively, where the first error bars refer to internal errors and the
second ones to systematic errors. In both clusters the [Fe/H] obtained for
TO-stars agree perfectly (within a few per cents) with that obtained for stars
at the base of the RGB. The [O/Fe]=0.21+/-0.05 value we obtain for NGC6397 is
quite low, but it agrees with previous results obtained for giants in this
cluster; also, the star-to-star scatter in both O and Fe is very small,
indicating that this small mass cluster is chemically very homogenous. On the
other side, our results show clearly and for the first time that the O-Na
anticorrelation (up to now seen only for stars on the red giant branches of
globular clusters) is present among unevolved stars in the globular cluster
NGC6752, a more massive cluster than NGC6397. A similar anticorrelation is
present also for Mg and Al, and C and N. It is very difficult to explain the
observed Na-O, and Mg-Al anticorrelation in NGC6752 stars by a deep mixing
scenario; we think it requires some non internal mechanism.

</DOC>
<DOC>
<DOCNO> 13898 </DOCNO>
Phase transition of the one-dimensional coagulation-production process


  Recently an exact solution has been found (M.Henkel and H.Hinrichsen,
cond-mat/0010062) for the 1d coagulation production process: 2A ->A, A0A->3A
with equal diffusion and coagulation rates. This model evolves into the
inactive phase independently of the production rate with $t^{-1/2}$ density
decay law. Here I show that cluster mean-field approximations and Monte Carlo
simulations predict a continuous phase transition for higher
diffusion/coagulation rates as considered in cond-mat/0010062. Numerical
evidence is given that the phase transition universality agrees with that of
the annihilation-fission model with low diffusions.

</DOC>
<DOC>
<DOCNO> 102032 </DOCNO>
Goursat's (n+1)-Webs


  We consider the Goursat's (n+1)-webs of codimension one of two kinds on an
n-dimensional manifold. They are characterized by the specific closed form
equations or by two special relations between components of the torsion tensor
of the web. These relations allow us to establish a connection with solutions
of two systems of nonlinear second-order PDEs investigated by Goursat in 1899.
The integrability conditions of some distributions invariantly associated with
both kinds of Goursat's (n+1)-webs are also investigated.

</DOC>
<DOC>
<DOCNO> 170084 </DOCNO>
Quantum decoherence of excitons in a leaky cavity with quasimode


  For the excitons in the quantum well placed within a leaky cavity, the
quantum decoherence of a mesoscopically superposed states is investigated based
on the factorization theory for quantum dissipation. It is found that the
coherence of the exciton superposition states will decrease in an oscillating
form when the cavity field interacting with the exciton is of the form of
quasimode. The effect of the thermal cavity fields on the quantum decoherence
of the superposition states of the exciton is studied and it is observed that
the higher the temperature of the environment is, the shorter the decoherence
characteristic time is.

</DOC>
<DOC>
<DOCNO> 100180 </DOCNO>
The R-matrix of the symplecto-orthogonal quantum superalgebra


  The R-matrix of the symplecto-orthogonal quantum superalgebra U_q(spo(2n|2m))
in the vector representation is calculated, and its basic properties are
derived.

</DOC>
<DOC>
<DOCNO> 12341 </DOCNO>
Single-mode delay time statistics for scattering by a chaotic cavity


  We investigate the low-frequency dynamics for transmission or reflection of a
wave by a cavity with chaotic scattering. We compute the probability
distribution of the phase derivative phi'=d phi/d omega of the scattered wave
amplitude, known as the single-mode delay time. In the case of a cavity
connected to two single-mode waveguides we find a marked distinction between
detection in transmission and in reflection: The distribution P(phi') vanishes
for negative phi' in the first case but not in the second case.

</DOC>
<DOC>
<DOCNO> 67783 </DOCNO>
Cosmology of Q-balls


  Supersymmetric extensions of the Standard Model predict the existence of
Q-balls, some of which can be entirely stable. Both stable and unstable Q-balls
can play an important role in cosmology.
  In particular, Affleck-Dine baryogenesis can result in a copious production
of stable baryonic Q-balls, which can presently exist as a form of dark matter.
Formation and decay of unstable Q-balls can also have some important effects on
baryogenesis and phase transitions.

</DOC>
<DOC>
<DOCNO> 70732 </DOCNO>
Real-time Nonequilibrium Dynamics in Hot QED Plasmas


  The quantum kinetics of photons is studied directly in real time by
implementing the dynamical renormalization group. In contrast to conventional
approach, the dynamical renormalization group method consistently includes
off-shell (energy non-conserving) effects and accounts for time-dependent
collisional kernel. To lowest order we find that in the relaxation time
approximation the semihard photon distribution function relaxes with a power
law.

</DOC>
<DOC>
<DOCNO> 102154 </DOCNO>
Bounded cohomology and non-uniform perfection of mapping class groups


  Using the existence of certain symplectic submanifolds in symplectic
4-manifolds, we prove an estimate from above for the number of singular fibers
with separating vanishing cycles in minimal Lefschetz fibrations over surfaces
of positive genus. This estimate is then used to deduce that mapping class
groups are not uniformly perfect, and that the map from their second bounded
cohomology to ordinary cohomology is not injective.

</DOC>
<DOC>
<DOCNO> 7660 </DOCNO>
Optical Limiting in Single-walled Carbon Nanotube Suspensions


  Optical limiting behaviour of suspensions of single-walled carbon nanotubes
in water, ethanol and ethylene glycol is reported. Experiments with 532 nm, 15
nsec duration laser pulses show that optical limiting occurs mainly due to
nonlinear scattering. The observed host liquid dependence of optical limiting
in different suspensions suggests that the scattering originates from
microbubbles formed due to absorption-induced heating.

</DOC>
<DOC>
<DOCNO> 71203 </DOCNO>
Macroscopically large antimatter regions in the baryon asymmetric


  The existence of macroscopic regions with antibaryon excess in the matter -
dominated Universe is a possible consequence of the evolution of baryon
charged, pseudo - Nambu - Goldstone field with lepton number violating
couplings. Such regions can survive the annihilation with surrounding matter
only in the case if their sizes exceeds the critical surviving size. The
evolution of survived antimatter - regions with high original antibaryon
density inside results in the formation of globular clusters, which is made out
from antimatter stars. The origin of antimatter regions in the chosen scenario
is accompanied the formation of closed domain walls, which can collapse into
massive black holes deposed inside the high density antimatter regions. This
fact can give us an additional hint, that an anti - stars globular cluster
could be one of the collapsed - core star clusters, which populate our galaxy.

</DOC>
<DOC>
<DOCNO> 7807 </DOCNO>
Irreversibility Line in Nb/CuMn Multilayers with a Regular Array of


  The transport properties of Nb/CuMn multilayers with a regular array of
electron beam lithography obtained antidots have been measured at different
temperatures in the presence of external perpendicular magnetic fields.
Hysteretical I-V characteristics have been observed which disappear when
approaching the upper critical magnetic field curve H_{c2}(T). Comparing these
data with other results (Arrhenius plots of resistive transition curves,
logV-logI characteristics) we have been able to relate the onset of the
hysteresis to the presence of an irreversibility line. We discuss several
possible mechanisms to clarify the nature of this line. Among them the most
plausible seems to be the vortex melting mainly induced by quantum
fluctuations.

</DOC>
<DOC>
<DOCNO> 12099 </DOCNO>
Collective pinning of a frozen vortex liquid in ultrathin


  The linear dynamic response of the two-dimensional (2D) vortex medium in
ultrathin YBa_2Cu_3O_7 films was studied by measuring their ac sheet impedance
Z over a broad range of frequencies \omega. With decreasing temperature the
dissipative component of Z exhibits, at a temperature T*(\omega) well above the
melting temperature of a 2D vortex crystal, a crossover from a thermally
activated regime involving single vortices to a regime where the response has
features consistent with a description in terms of a collectively pinned vortex
manifold. This suggests the idea of a vortex liquid which, below T*(\omega),
appears to be frozen at the time scales 1/\omega of the experiments.

</DOC>
<DOC>
<DOCNO> 150488 </DOCNO>
Conformal and Superconformal Mechanics


  We investigate the conformal and superconformal properties of a
non-relativistic spinning particle propagating in a curved background coupled
to a magnetic field and with a scalar potential. We derive the conditions on
the couplings for a large class of such systems which are necessary in order
their actions admit conformal and superconformal symmetry. We find that some of
these conditions can be encoded in the conformal and holomorphic geometry of
the background. Several new examples of conformal and superconformal models are
also given.

</DOC>
<DOC>
<DOCNO> 117849 </DOCNO>
The Distance to the Large Magellanic Cloud


  I demonstrate that the two unexpected results in the local Universe:
anomalous intrinsic (V-I)_0 colors of RR Lyrae stars and clump giants in the
Galactic center, and very short distances to Magellanic Clouds inferred from
clump giants, can be at least partially resolved with a modified coefficient of
selective extinction A_V/E(V-I). With this modification, I find a new
clump-giant distance modulus to the Large Magellanic Cloud, mu_{LMC} = 18.27
+/- 0.07, which is 0.09 larger than the Udalski (1998b) result. When distance
estimates from the red clump, RR Lyrae stars and the eclipsing binary HV2274
are combined, one obtains mu_{LMC} = 18.31 +/- 0.04 (internal).

</DOC>
<DOC>
<DOCNO> 122909 </DOCNO>
The non-stellar infrared continuum of Seyfert galaxies


  JHKL'M (1-5 micron) imaging of a sample of Seyfert (Sy) 2 galaxies is
presented. We confirm that the 1-2.2 micron nuclear continuum of some Sy 2s is
dominated by stellar emission, whereas the continuum emission at longer
wavelengths (3-5 micron) is almost entirely non-stellar in origin. The IR
non-stellar spectral energy distributions (SED) (up to 15 micron) of Sy
galaxies show a variety of shapes, and they are well reproduced with the
tapered disk models of Efstathiou & Rowan-Robinson (1995). We have used two
models, one including an optically thin cone component and a coneless model.
Although our modelling of the SEDs does not allow us to favor either model to
account for all the observed SEDs, we find that the viewing angle towards the
central source is well constrained by both models. We have also investigated
non-stellar color-color diagrams. The colors of the Sy galaxies with viewing
angles theta < 30 degree are better reproduced with the cone model. These
diagrams provide a good means to separate Sy 2s with moderate obscuration (A_V
< 20 mag, from hard X-ray observations) from those with high obscuration. The
ground-based 4.8 micron and ISO 9.6 micron luminosities are well correlated
with the hard X-ray luminosities of Sy 1s and 2s. These continuum emissions
appear as a good indicator of the AGN luminosity, at least in the cases of hard
X-ray Compton-thin Sy galaxies. We finally stress the finding that some Compton
thick galaxies show bright non-stellar emission at 5 micron. This suggests that
the near-IR emission in Sys is produced in an extended component illuminated by
the central source, that is more visible from all viewing angles. We discuss
possible implications of mid-IR surveys for the search of counterparts of
highly obscured hard X-ray sources. (Abridged)

</DOC>
<DOC>
<DOCNO> 85607 </DOCNO>
Gravitomagnetism, clocks and geometry


  New techniques to evaluate the clock effect using light are described. These
are based on the flatness of the cylindrical surface containing the world lines
of the rays constrained to move on circular trajectories about a spinning mass.
The effect of the angular momentum of the source is manifested in the fact that
inertial observers must be replaced by local non rotating observers. Starting
from this an exact formula for circular trajectories is found. Numerical
estimates for the Earth environment show that light would be a better probe
than actual clocks to evidence the angular momentum influence. The advantages
of light in connection with some principle experiments are shortly reviewed.

</DOC>
<DOC>
<DOCNO> 100024 </DOCNO>
The connectedness of the moduli space of maps to homogeneous spaces


  We prove the connectedness of the moduli space of maps (of fixed genus and
homology class) to the homogeneous space G/P by degeneration via the maximal
torus action. In the genus 0 case, the irreducibility of the moduli of maps is
a direct consequence of connectedness. An analysis of a related
Bialynicki-Birula stratification of the map space yields a rationality result:
the (coarse) moduli space of genus 0 maps to G/P is a rational variety. The
rationality argument depends essentially upon rationality results for quotients
of SL2 representations proven by Katsylo and Bogomolov.

</DOC>
<DOC>
<DOCNO> 122643 </DOCNO>
Results from Microlensing Searches for Extrasolar Planets


  Specially-designed microlensing searches, some of which have been underway
for several years, are sensitive to extrasolar planets orbiting the most common
stars in our Galaxy. Microlensing is particularly well-suited to the detection
of Jupiter-mass planets orbiting their parent stars at several AU. Since Jovian
analogs are thought to influence the subsequent evolution of most planetary
systems, they are particularly important to study. The orbital radii and
distances to the planetary systems probed by microlensing are larger than those
currently studied by radial velocity techniques; the two methods are thus
complementary. Recent results from microlensing searches are discussed,
including constraints on Jovian analogs orbiting typical Galactic stars.
Benefits and drawbacks of the technique for the characterization of planetary
systems, and future prospects are briefly reviewed.

</DOC>
<DOC>
<DOCNO> 8201 </DOCNO>
Light Scattering from Nonequilibrium Concentration Fluctuations in a


  We have performed light-scattering measurements in dilute and semidilute
polymer solutions of polystyrene in toluene when subjected to stationary
temperature gradients. Five solutions with concentrations below and one
solution with a concentration above the overlap concentration were
investigated. The experiments confirm the presence of long-range nonequilibrium
concentration fluctuations which are proportional to $(\nabla T)^2/k^4$, where
$\nabla T$ is the applied temperature gradient and $k$ is the wave number of
the fluctuations. In addition, we demonstrate that the strength of the
nonequilibrium concentration fluctuations, observed in the dilute and
semidilute solution regime, agrees with theoretical values calculated from
fluctuating hydrodynamics. Further theoretical and experimental work will be
needed to understand nonequilibrium fluctuations in polymer solutions at higher
concentrations.

</DOC>
<DOC>
<DOCNO> 71773 </DOCNO>
Quark Correlations Inside Hadrons And Single Diffraction


  Hadron structure is considered in the frame of Strongly Correlated Quark
Model (SCQM). It is shown that quark correlations result in fluctuations of
hadronic matter distributions and single diffractive dissociation processes in
hadronic collisions, hard or soft, are manifestation of these fluctuations
inside colliding hadrons.

</DOC>
<DOC>
<DOCNO> 9500 </DOCNO>
Optical Absorption Spectra of Bipolarons


  The absorption of large bipolarons is investigated using the path-integral
method. The response of a bipolaron to an external electromagnetic field is
derived in the framework of the memory-function approach. The bipolaron optical
absorption spectrum consists of a series of relatively narrow peaks. The
peculiarities of the bipolaron optical absorption as a function of the
frequency of the electromagnetic field may be attributed to the transitions
involving relaxed excited states and scattering states of a bipolaron.

</DOC>
<DOC>
<DOCNO> 150789 </DOCNO>
K\"ahler Potential of Moduli Space of Calabi-Yau $d$-fold embedded in


  We study a kaehler potential K of a one parameter family of Calabi-Yau d-fold
embedded in CP^{d+1}. By comparing results of the topological B-model and the
data of the CFT calculation at Gepner point, the K is determined unambiguously.
It has a moduli parameter psi that describes a deformation of the CFT by a
marginal operator. Also the metric, curvature and hermitian two-point functions
in the neighborhood of the Gepner point are analyzed. We use a recipe of tt^{*}
fusion and develop a method to determine the K from the point of view of
topological sigma model. It is not restricted to this specific model and can be
applied to other Calabi-Yau cases.

</DOC>
<DOC>
<DOCNO> 121395 </DOCNO>
Evidence for a Long-period Planet Orbiting Epsilon Eridani


  High precision radial velocity (RV) measurements spanning the years
1980.8--2000.0 are presented for the nearby (3.22 pc) K2 V star $\epsilon$ Eri.
These data, which represent a combination of six independent data sets taken
with four different telescopes, show convincing variations with a period of
$\approx$ 7 yrs. A least squares orbital solution using robust estimation
yields orbital parameters of period, $P$ = 6.9 yrs, velocity $K$-amplitude $=$
19 {\ms}, eccentricity $e$ $=$ 0.6, projected companion mass $M$ sin $i$ = 0.86
$M_{Jupiter}$, and semi-major axis $a_2$ $=$ 3.3 AU. Ca II H&K S-index
measurements spanning the same time interval show significant variations with
periods of 3 and 20 yrs, yet none at the RV period. If magnetic activity were
responsible for the RV variations then it produces a significantly different
period than is seen in the Ca II data. Given the lack of Ca II variation with
the same period as that found in the RV measurements, the long-lived and
coherent nature of these variations, and the high eccentricity of the implied
orbit, Keplerian motion due to a planetary companion seems to be the most
likely explanation for the observed RV variations. The wide angular separation
of the planet from the star (approximately 1 arc-second) and the long orbital
period make this planet a prime candidate for both direct imaging and
space-based astrometric measurements.

</DOC>
<DOC>
<DOCNO> 122331 </DOCNO>
The history of starburst galaxies


  Dusty galaxies with luminosities in excess of 10^11 solar luminosities have
been detected out to redshifts of about unity by the Infrared Space Observatory
(ISO), and to higher redshifts using millimetre(mm)- and submm-wave cameras on
ground-based telescopes. The integrated properties of these more distant
galaxies are also constrained by measurements of the intensity of the
submm-wave background radiation. While it is generally unclear whether their
energy is released by gravitational accretion or by star formation,
circumstantial evidence favours star formation. Unless these high-redshift
galaxies are extremely massive, which is not expected from standard models of
galaxy evolution, this luminosity cannot be sustained for more than a fraction
of a Hubble time, and so they are undergoing some sort of `bursting' behaviour.
The interpretation and analysis of this population is discussed, and the key
observations for deriving a robust history of their evolution, which is likely
to be the history of starburst activity, are highlighted.

</DOC>
<DOC>
<DOCNO> 118404 </DOCNO>
An Effective Temperature Scale for Late M and L Dwarfs, from Resonance


  We present Keck HIRES spectra of 6 late-M dwarfs and 11 L dwarfs. Our goal is
to assign effective temperatures to the objects using detailed atmospheric
models and fine analysis of the alkali resonance absorption lines of CsI and
RbI. These yield mutually consistent results (+-150 K) when we use
``cleared-dust'' models, which account for the removal of refractory species
from the molecular states but do not include dust opacities. We find a tendency
for the RbI line to imply a slightly higher temperature, which we ascribe to an
incomplete treatment of the overlying molecular opacities. The final effective
temperatures we adopt are based on the CsI fits alone, though the RbI fits
support the CsI temperature sequence. This work, in combination with results
from the infrared, hints that dust in these atmospheres has settled out of the
high atmosphere but is present in the deep photosphere. We also derive radial
and rotational velocities for all the objects, finding that the previously
discovered trend of rapid rotation for very low mass objects is quite
pervasive. To improve on our analysis, there is a clear need for better
molecular line lists and a more detailed understanding of dust formation and
dynamics.

</DOC>
<DOC>
<DOCNO> 70340 </DOCNO>
Particle Densities in Heavy Ion Collisions at High Energy and the Dual


  We analyse recent results on charged particle pseudo-rapidity densities from
RHIC in the framework of the Dual String Model, in particular when including
string fusion. The model, in a simple way, agrees with all the existing data
and is consistent with the presence of the percolation transition to the
Quark-Gluon Plasma already at the CERN-SPS.

</DOC>
<DOC>
<DOCNO> 170626 </DOCNO>
Quadrupole Contribution in Semiclassical Radiation Theory


  Within the frame-work of semiclassical theory two-level approximation in
atomic system has been considered. Model proposed by M.D. Crisp and E.T. Jaynes
has been modified. It has been shown that the time-dependent frequency shift
depends on the higher multipole moments, retained in the Taylor expansion of
electromagnetic field.

</DOC>
<DOC>
<DOCNO> 99932 </DOCNO>
Isothermic surfaces: conformal geometry, Clifford algebras and


  We give an account of the classical and integrable geometry of isothermic
surfaces in arbitrary co-dimension. We show that the classical transformation
theory of Darboux, Bianchi and Calapso goes through unchanged in arbitrary
co-dimension as does the connection with the "curved flats" of Ferus and Pedit.
Moreover, we identify Darboux transformations with the dressing action of
"simple factors" in the sense of Terng and Uhlenbeck. In so doing, we advertise
the use of Vahlen's Clifford algebra matrices as an efficient computational
tool in conformal geometry.

</DOC>
<DOC>
<DOCNO> 13255 </DOCNO>
Option Pricing and Hedging with Temporal Correlations


  We consider the problem of option pricing and hedging when stock returns are
correlated in time. Within a quadratic-risk minimisation scheme, we obtain a
general formula, valid for weakly correlated non-Gaussian processes. We show
that for Gaussian price increments, the correlations are irrelevant, and the
Black-Scholes formula holds with the volatility of the price increments on the
scale of the re-hedging. For non-Gaussian processes, further non trivial
corrections to the `smile' are brought about by the correlations, even when the
hedge is the Black-Scholes Delta-hedge. We introduce a compact notation which
eases the computations and could be of use to deal with more complicated
models.

</DOC>
<DOC>
<DOCNO> 101861 </DOCNO>
Global Existence for Systems of Nonlinear Wave Equations in 3D with


  Global smooth solutions to the initial value problem for systems of nonlinear
wave equations with multiple propagation speeds will be constructed in the case
of small initial data and nonlinearities satisfying the null condition.

</DOC>
<DOC>
<DOCNO> 102666 </DOCNO>
On shape optimization and the Pompeiu problem


  The Pompeiu problem is considered as shape optimization problem. We show
stability of the ball which is the minimum point of related domain functional.
The proof is based on shape derivative method. Stability of the ball for
general domain functionals invariant under the rigid motions is discussed.

</DOC>
<DOC>
<DOCNO> 123074 </DOCNO>
Coronal cooling and its signatures in the rapid aperiodic variability of


  The most popular models for the complex phase and time lags in the rapid
aperiodic variability of Galactic X-ray binaries are based Comptonization of
soft seed photons in a hot corona, where small-scale flares are induced by
flares of the soft seed photon input (presumably from a cold accretion disc).
However, in their original version, these models have neglected the additional
cooling of the coronal plasma due to the increased soft seed photon input, and
assumed a static coronal temperature structure. In this paper, our
Monte-Carlo/Fokker-Planck code for time-dependent radiation transfer and
electron energetics is used to simulate the self-consistent coronal response to
the various flaring scenarios that have been suggested to explain phase and
time lags observed in some Galactic X-ray binaries. It is found that the
predictions of models involving slab-coronal geometries are drastically
different from those deduced under the assumption of a static corona. However,
with the inclusion of coronal cooling they may even be more successful than in
their original version in explaining some of the observed phase and time lag
features. The predictions of the model of inward-drifting density perturbations
in an ADAF-like, two-temperature flow also differ from the static-corona case
previously investigated, but may be consistent with the alternating phase lags
seen in GRS 1915+105 and XTE J1550-564. Models based on flares of a cool disc
around a hot, inner two-temperature flow may be ruled out for most objects
where significant Fourier-frequency-dependent phase and time lags have been
observed.

</DOC>
<DOC>
<DOCNO> 117478 </DOCNO>
The Stellar Content of Obscured Galactic Giant H II Regions: II. W42


  We present near infrared J, H, and K images and K-band spectroscopy in the
giant HII region W42. A massive star cluster is revealed; the color-color plot
and K-band spectroscopic morphology of two of the brighter objects suggest the
presence of young stellar objects. The spectrum of the bright central star is
similar to unobscured stars with MK spectral types of O5-O6.5. If this star is
on the zero age main sequence, then the derived spectrophotometric distance is
considerably smaller than previous estimates. The Lyman continuum luminosity of
the cluster is a few times that of the Trapezium. The slope of the K-band
luminosity function is similar to that for the Trapezium cluster and
significantly steeper than that for the massive star cluster in M17 or the
Arches cluster near the Galactic center.

</DOC>
<DOC>
<DOCNO> 8118 </DOCNO>
Evidence for nodal quasiparticles in electron-doped cuprates from


  The in-plane magnetic penetration depth, $\lambda (T)$, was measured down to
0.4 K in single crystals of electron-doped superconductors,
Pr$_{1.85}$Ce$_{0.15}$CuO$_{4-\delta}$ (PCCO) and
Nd$_{1.85}$Ce$_{0.15}$CuO$_{4-\delta}$ (NCCO). In PCCO, the superfluid density
varies as $T^2$ from 0.025 up to roughly 0.3 $T/T_c$ suggestive of a d-wave
state with impurities. In NCCO, $\lambda (T)$ shows a pronounced upturn for $T
< 4$ K due to the paramagnetic contribution of Nd$^{3+}$ ions. Fits to an
s-wave order parameter over the standard BCS range ($T/T_c$ = 0.32) limit any
gap to less than $\Delta_{min} (0)/T_c = 0.57$ in NCCO. For PCCO, the absence
of paramagnetism permits a lower temperature fit and yields an upper limit of
$\Delta_{min} (0)/T_c = 0.2$.

</DOC>
<DOC>
<DOCNO> 71894 </DOCNO>
Nonrelativistic Bound States in Quantum Field Theory


  Nonrelativistic bound states are studied using an effective field theory.
Large logarithms in the effective theory can be summed using the velocity
renormalization group. For QED, one can determine the structure of the leading
and next-to-leading order series for the energy, and compute corrections up to
order alpha^8 ln^3 alpha, which are relevant for the present comparison between
theory and experiment. For QCD, one can compute the velocity renormalization
group improved quark potentials. Using these to compute the renormalization
group improved t-tbar production cross-section near threshold gives a result
with scale uncertainties of 2%, a factor of 10 smaller than existing fixed
order calculations.

</DOC>
<DOC>
<DOCNO> 81000 </DOCNO>
Algebraic Multigrid for Disordered Systems and Lattice Gauge Theories


  The construction of multigrid operators for disordered linear lattice
operators, in particular the fermion matrix in lattice gauge theories, by means
of algebraic multigrid and block LU decomposition is discussed. In this
formalism, the effective coarse-grid operator is obtained as the Schur
complement of the original matrix. An optimal approximation to it is found by a
numerical optimization procedure akin to Monte Carlo renormalization, resulting
in a generalized (gauge-path dependent) stencil that is easily evaluated for a
given disorder field. Applications to preconditioning and relaxation methods
are investigated.

</DOC>
<DOC>
<DOCNO> 83292 </DOCNO>
Data sonification and sound visualization


  This article describes a collaborative project between researchers in the
Mathematics and Computer Science Division at Argonne National Laboratory and
the Computer Music Project of the University of Illinois at Urbana-Champaign.
The project focuses on the use of sound for the exploration and analysis of
complex data sets in scientific computing. The article addresses digital sound
synthesis in the context of DIASS (Digital Instrument for Additive Sound
Synthesis) and sound visualization in a virtual-reality environment by means of
M4CAVE. It describes the procedures and preliminary results of some experiments
in scientific sonification and sound visualization.

</DOC>
<DOC>
<DOCNO> 71111 </DOCNO>
Moduli Evolution in Heterotic Scenarios


  We discuss several aspects of the cosmological evolution of moduli fields in
heterotic string/M-theory scenarios. In particular we study the equations of
motion of both the dilaton and overall modulus of these theories in the
presence of an expanding Universe and under different assumptions. First we
analyse the impact of their couplings to matter fields, which turns out to be
negligible in the string and M-theory scenarios. Then we examine in detail the
possibility of scaling in M-theory, i.e. how the moduli would evolve naturally
to their minima instead of rolling past them in the presence of a dominating
background. In this case we find interesting and positive results, and we
compare them to the analogous situation in the heterotic string.

</DOC>
<DOC>
<DOCNO> 170399 </DOCNO>
Multiparty key distribution and secret sharing based on entanglement


  A general proof of the security against eavesdropping of a previously
introduced protocol for two-party quantum key distribution based on
entanglement swapping [Phys. Rev. A {\bf 61}, 052312 (2000)] is provided. In
addition, the protocol is extended to permit multiparty quantum key
distribution and secret sharing of classical information.

</DOC>
<DOC>
<DOCNO> 13170 </DOCNO>
A Method to Extract Potentials from the Temperature Dependence of


  It is shown that the temperature dependence of Langmuir constants contains
all the information needed to determine spherically averaged intermolecular
potentials. An analytical ``inversion'' method based on the standard
statistical model of van der Waals and Platteeuw is presented which extracts
cell potentials directly from experimental data. The method is applied to
ethane and cyclopropane clathrate-hydrates, and the resulting potentials are
much simpler and more meaningful than those obtained by the usual method of
numerical fitting with Kihara potentials.

</DOC>
<DOC>
<DOCNO> 39701 </DOCNO>
Recent Results from the L3 Experiment


  A data sample corresponding to an integrated luminosity of 232pb^-1 was
collected in 1997 and 1998 by the L3 experiment at LEP in e+e- collisions at
centre-of-mass energies between 181.7GeV and 188.7GeV. Pair production of
fermions and bosons is studied and compared with the Standard Model
expectations. Events with a single detected photon or W boson are also
considered. The measurement of several Standard Model cross sections is
discussed. The presence and the magnitude of triple couplings of charged and
neutral electroweak gauge bosons is investigated. These processes are used to
probe New Physics beyond the Standard Model, including the existence of extra
spatial dimensions.

</DOC>
<DOC>
<DOCNO> 85441 </DOCNO>
Binary black holes coalescence: transition from adiabatic inspiral to


  Using two recent techniques giving non-perturbative re-summed estimates of
the damping and of the conservative part of the dynamics of two-body systems,
we describe the transition between adiabatic inspiral and plunge in binary
non-spinning black holes moving along quasi-circular orbits.

</DOC>
<DOC>
<DOCNO> 117817 </DOCNO>
Strong and weak lensing analysis of cluster Abell 2219 based on optical


  We present a gravitational lensing study of the massive galaxy cluster A2219
(redshift 0.22). This investigation is based on multicolour images from U
through H, which allows photometric redshifts to be estimated for the
background sources. The redshifts provide useful extra information for the
lensing models: we show how they can be used to identify a new multiple-image
system (and rule out an old one), how this information can be used to anchor
the mass model for the cluster, and how the redshifts can be used to construct
optimal samples of background galaxies for a weak lensing analysis. Combining
all results, we obtain the mass distribution in this cluster from the inner,
strong lensing region, out to a radius of 1.5 Mpc. The mass profile is
consistent with a singular isothermal model over this radius range. Parametric
and non-parametric reconstructions of the mass distribution in the cluster are
compared. The main features (elongation, sub-clumps, radial mass profile) are
in good agreement.

</DOC>
<DOC>
<DOCNO> 70832 </DOCNO>
The radial wavefunctions of a heavy-light meson calculated on a lattice


  A brief review is given of attempts to understand the energies of four-quark
systems calculated on a lattice in terms of nuclear-physics-inspired many-body
techniques involving interquark potentials. Results are given for the next
stage of this study where the wavefunctions of heavy-light mesons are also
calculated on a lattice.

</DOC>
<DOC>
<DOCNO> 119380 </DOCNO>
Globular Clusters in the dE,N galaxy NGC 3115 DW1: New Insights from


  The properties of globular clusters in dwarf galaxies are key to
understanding the formation of globular cluster systems, and in particular in
verifying scenarios in which globular cluster systems of larger galaxies formed
(at least partly) from the accretion of dwarf galaxies. Here, we revisit the
globular cluster system of the dE,N galaxy NGC 3115 DW1 - a companion of the
nearby S0 galaxy NGC 3115 - adding Keck/LRIS spectroscopy and HST/WFPC2 imaging
to previous ground-based photometry. Spectra for seven globular clusters reveal
normal abundance ratios with respect to the Milky Way and M31 clusters, as well
as a relatively high mean metallicity ([Fe/H] = -1.0+/-0.1 dex). Crude
kinematics indicate a high velocity dispersion within 10 kpc which could either
be caused by dark matter dominated outer regions, or by the stripping of outer
globular clusters by the nearby giant galaxy NGC 3115. The total galaxy mass
out to 3 and 10 kpc lies between 10^10 and 10^11 solar masses and 2*10^10 and
4*10^11 solar masses, respectively, depending on the mass estimator used and
the assumptions on cluster orbits and systemic velocity. The HST imaging allows
measurement of sizes for two clusters, returning core radii around 2.0 pc,
similar to the sizes observed in other galaxies. Spectroscopy allows an
estimate of the degree of contamination by foreground stars or background
galaxies for the previous ground-based photometry, but does not require a
revision of previous results: NGC 3115 DW1 hosts around 60+/-20 clusters which
corresponds to a specific frequency of 4.9+/-1.9, on the high end for massive
dEs. Given its absolute magnitude (M_V=-17.7 mag) and the properties of its
cluster system, NGC 3115 DW1 appears to be a transition between a luminous dE
and low-luminosity E galaxy.

</DOC>
<DOC>
<DOCNO> 10987 </DOCNO>
First- and second-order transitions of the escape rate in ferrimagnetic


  Quantum-classical escape-rate transition has been studied for two general
forms of magnetic anisotropy in ferrimagnetic or antiferromagnetic particles.
It is found that the range of the first-order transition is greatly reduced as
the system becomes ferrimagnetic and there is no first-order transition in
almost compensated antiferromagnetic particles. These features can be tested
experimentally in nanomagnets like molecular magnets.

</DOC>
<DOC>
<DOCNO> 122785 </DOCNO>
Force-Free Models of Magnetically Linked Star-Disk Systems


  Disk accretion onto a magnetized star occurs in a variety of astrophysical
contexts, from young stars to X-ray pulsars. The magnetohydrodynamic
interaction between the stellar field and the accreting matter can have a
strong effect on the disk structure, the transfer of mass and angular momentum
between the disk and the star, and the production of bipolar outflows, e.g.,
plasma jets. We study a key element of this interaction - the time evolution of
the magnetic field configuration brought about by the relative rotation between
the disk and the star - using simplified, largely semianalytic, models. We
first discuss the rapid inflation and opening up of the magnetic field lines in
the corona above the accretion disk, which is caused by the differential
rotation twisting. Then we consider additional physical effects that tend to
limit this expansion, such as the effect of plasma inertia and the possibility
of reconnection in the disk's corona, the latter possibly leading to repeated
cycles in the evolution. We also derive the condition for the existence of a
steady state for a resistive disk and conclude that a steady state
configuration is not realistically possible. Finally, we generalize our
analysis of the opening of magnetic field lines by using a non-self-similar
numerical model that applies to an arbitrarily rotating (e.g. keplerian) disk.

</DOC>
<DOC>
<DOCNO> 122204 </DOCNO>
Color Gradients and the Secular Evolutionary Scenario in Late-Type


  We have done a robust statistical study of the behaviour of color profiles
for 257 Sbc galaxies, having determined (B-V) and (U-B) color gradients, as
well as color indices of bulges and disks separately. Applying a bidimensional
decomposition technique to model the brightness profiles of bulges and disks,
we obtained characteristic structural parameters for 39 galaxies. Among the
main results obtained, we point out: 65% of the galaxies have negative color
gradients (reddish inward), 25% have no gradients, and 10% show positive
gradients; galaxies that show no color gradients tend to be barred; we confirm
the correlation between the color indices of bulges and disks; the absence of
correlation between color and metallicity gradients suggests that the excess of
barred galaxies with zero or positive color gradients reflects a difference in
the behaviour of the mean age of the stellar population along barred and
unbarred galaxies; galaxies with zero or positive color gradients show a slight
tendency of having larger bulges, with a greater central concentration of
light, and we confirm the correlation between the scale lengths of bulges and
disks. These results are compatible and favourable to the secular evolutionary
scenario, in which stellar bars induce radial mass fluxes to the central
regions of galaxies. (Abridged)

</DOC>
<DOC>
<DOCNO> 169690 </DOCNO>
Heating of trapped ions from the quantum ground state


  We have investigated motional heating of laser-cooled 9Be+ ions held in
radio-frequency (Paul) traps. We have measured heating rates in a variety of
traps with different geometries, electrode materials, and characteristic sizes.
The results show that heating is due to electric-field noise from the trap
electrodes which exerts a stochastic fluctuating force on the ion. The scaling
of the heating rate with trap size is much stronger than that expected from a
spatially uniform noise source on the electrodes (such as Johnson noise from
external circuits), indicating that a microscopic uncorrelated noise source on
the electrodes (such as fluctuating patch-potential fields) is a more likely
candidate for the source of heating.

</DOC>
<DOC>
<DOCNO> 12227 </DOCNO>
Balanced Branching in Transcription Termination


  The theory of stochastic transcription termination based on free-energy
competition requires two or more reaction rates to be delicately balanced over
a wide range of physical conditions. A large body of work on glasses and large
molecules suggests that this should be impossible in such a large system in the
absence of a new organizing principle of matter. We review the experimental
literature of termination and find no evidence for such a principle but many
troubling inconsistencies, most notably anomalous memory effects. These suggest
that termination has a deterministic component and may conceivably be not
stochastic at all. We find that a key experiment by Wilson and von Hippel
allegedly refuting deterministic termination was an incorrectly analyzed
regulatory effect of Mg2+ binding.

</DOC>
<DOC>
<DOCNO> 170165 </DOCNO>
Einstein and Bell, von Mises and Kolmogorov: reality and locality,


  We perform analysis of Bell's arguments (and their generalizations) on the
basis of the frequency approach to probability theory (R. von Mises, 1919).
This analysis demonstrated that there are no physical arguments which support
the existence of `probability distributions' which were formally used in all
investigations based on the conventional (Kolmogorov, 1933) approach to
probability theory. In fact, probability distributions may fluctuate from run
to run (no collectives). This chaos on the microlevel need not contradict to
the stabilization of frequencies for physical observables. We discuss the
relation to the completeness of quantum mechanics (and the efficiency of
detectors). If micro-reality is also statistically stable (as the
macro-reality), then the only root of the violation of Bell's inequality (or
CHSH inequality) is the dependence of collectives corresponding to two
different measurement devices. Such a dependence implies the violation of the
factorization rule for the simultaneous probability distribution. Formally this
rule coincides with the well known BCHS locality condition (or outcome
independence condition). However, von Mises' approach implies completely
different interpretation of dependence. It is not a dependence of events, but
it is a dependence of collectives (merely via the same preparation procedure).

</DOC>
<DOC>
<DOCNO> 118289 </DOCNO>
Reionization and the abundance of galactic satellites


  One of the main challenges facing standard hierarchical structure formation
models is that the predicted abundance of galactic subhalos with circular
velocities of 10-30 km/s is an order of magnitude higher than the number of
satellites actually observed within the Local Group. Using a simple model for
the formation and evolution of dark halos, based on the extended
Press-Schechter formalism and tested against N-body results, we show that the
theoretical predictions can be reconciled with observations if gas accretion in
low-mass halos is suppressed after the epoch of reionization. In this picture,
the observed dwarf satellites correspond to the small fraction of halos that
accreted substantial amounts of gas before reionization. The photoionization
mechanism naturally explains why the discrepancy between predicted halos and
observed satellites sets in at about 30 km/s, and for reasonable choices of the
reionization redshift (z_re = 5-12) the model can reproduce both the amplitude
and shape of the observed velocity function of galactic satellites. If this
explanation is correct, then typical bright galaxy halos contain many low-mass
dark matter subhalos. These might be detectable through their gravitational
lensing effects, through their influence on stellar disks, or as dwarf
satellites with very high mass-to-light ratios. This model also predicts a
diffuse stellar component produced by large numbers of tidally disrupted
dwarfs, perhaps sufficient to account for most of the Milky Way's stellar halo.

</DOC>
<DOC>
<DOCNO> 13385 </DOCNO>
Geometrically induced spectrum in curved leaky wires


  We study measure perturbations of the Laplacian in $L^2(\R^2)$ supported by
an infinite curve $\Gamma$ in the plane which is asymptotically straight in a
suitable sense. We show that if $\Gamma$ is not a straight line, such a ``leaky
quantum wire'' has at least one bound state below the threshold of the
essential spectrum.

</DOC>
<DOC>
<DOCNO> 151637 </DOCNO>
Does Superstring Theory Have a Conformally Invariant Limit?


  This talk describes a proposal, due to Hull, for a conformally invariant
limit of superstring theory in six dimensions.

</DOC>
<DOC>
<DOCNO> 69953 </DOCNO>
Twist-three effects in two-photon processes


  We give a general treatment of twist-three effects in two-photon reactions.
We address the issue of the gauge invariance of the Compton amplitude in
generalized Bjorken kinematics and relations of twist-three `transverse' skewed
parton distributions to twist-two ones and interaction dependent three-particle
correlation functions. Finally, we discuss leading order evolution of
twist-three functions and their impact on the deeply virtual Compton
scattering.

</DOC>
<DOC>
<DOCNO> 71303 </DOCNO>
Electroweak phase transition beyond the Standard Model


  Standard theories of electroweak interactions are based on the concept of a
gauge symmetry broken by the Higgs mechanism. If they are placed in an
environment with a sufficiently high temperature, the symmetry gets restored.
It turns out that the characteristics of the symmetry restoring phase
transition, such as its order, are important for cosmological applications,
such as baryon asymmetry generation. We first briefly review how, by a
combination of analytic and numerical methods, the properties of the phase
transition can be systematically resolved for any given type of a (weakly
interacting) Higgs sector. We then summarise the numerical results available
for the Standard Model, and present a generic model independent statement as to
how the Higgs sector should differ from the Standard Model for the properties
of the transition to be very different. As an explicit example, we discuss the
possibilities available for a strong transition in the experimentally allowed
parameter region of the Minimal Supersymmetric Standard Model.

</DOC>
<DOC>
<DOCNO> 152372 </DOCNO>
Comments Concerning the CFT Description of Small Objects in AdS


  In this paper we resolve a contradiction posed in a recent paper by Horowitz
and Hubeny. The contradiction concerns the way small objects in AdS space are
described in the holographic dual CFT description.

</DOC>
<DOC>
<DOCNO> 118629 </DOCNO>
Steepening of Afterglow Decay for Jets Interacting with Stratified Media


  We calculate light-curves for Gamma-Ray Burst afterglows when material
ejected in the explosion is confined to a jet which propagates in a medium with
a power-law density profile. The observed light-curve decay steepens by a
factor of $\Gamma^2$ when an observer sees the edge of the jet. In a uniform
density medium the increase in the power-law index ($\beta$) of the light-curve
as a result of this {\it edge effect} is $\sim0.7$ and is completed over one
decade in observer time. For a pre-ejected stellar wind ($\rho \propto r^{-2}$)
$\beta$ increases by $\sim0.4$ over two decades in time due to the edge effect
and the steepening of the light-curve due to the jet sideways expansion takes
about four decades in time. Therefore, a break in the light-curve for a jet in
a wind model is unlikely to be detected even for very narrow jets of opening
angle of a few degrees or less, in which case the lateral expansion occurs at
early times when the afterglow is bright.
  The light-curve for the afterglow of GRB 990510, for which an increase in
$\beta$ of approximately 1.35 was observed on a time scale of 3 days, cannot be
explained only by the sideways expansion and the edge effects in a jet in a
uniform ISM -- the increase in $\beta$ is too large and too rapid. However, the
passage of the cooling or synchrotron peak frequencies through the observing
band at about 0.1 -- 1 day together with jet edge effect explains the observed
data. The jet opening angle is found to be $\sim 5^o$ and the energy in the
explosion to be less than about $10^{50}$ erg.

</DOC>
<DOC>
<DOCNO> 151209 </DOCNO>
Noncommutative geometry and physics: a review of selected recent results


  This review is based on two lectures given at the 2000 TMR school in Torino.
We discuss two main themes: i) Moyal-type deformations of gauge theories, as
emerging from M-theory and open string theories, and ii) the noncommutative
geometry of finite groups, with the explicit example of Z_2, and its
application to Kaluza-Klein gauge theories on discrete internal spaces.

</DOC>
<DOC>
<DOCNO> 72017 </DOCNO>
From Hard to Soft Diffraction and Return


  The long standing mystery of smallness of diffractive dissociation of hadrons
to large effective masses (the Pomeron-proton cross section is only 2 mb)
witnesses that the gluonic clouds of valence quarks are so small (r_0=0.3fm)
that soft interaction hardly resolves those gluons (diffraction is \propto
r_0^4). A color-dipole light-cone (LC) approach is developed which incorporates
a strong nonperturbative interaction of the LC gluons. The energy dependent
part of the total hadronic cross section is calculated in a parameter-free way
employing the nonperturbative LC wave functions of the quark-gluon Fock states.
It rises with energy as s^\Delta, and we predict \Delta=0.17 +/- 0.01, as well
as the normalization. However, the energy independent part of the cross section
related to inelastic collisions with no gluon radiated (gluons are not
resolved) cannot be calculated reliably and we treat it as an adjustable
parameter which is fixed fitting just one experimental point for total cross
section. Then the energy dependence of the total cross section (the Pomeron
part) and the elastic slope are fully predicted, as well as the effective
Pomeron trajectory in impact parameter space, in a good agreement with data.
These results naturally explain the x-dependence of the diffractive DIS
observed at HERA. Although diffraction is expected to be dominated by soft
interactions the observed effective \Delta is about twice as large as one
(0.08) known for total cross sections. Diffractive excitations of large
effective mass correspond to diffractive gluon radiation and should be
associated with our calculated \Delta.

</DOC>
<DOC>
<DOCNO> 10208 </DOCNO>
On the universal optical conductivity and single-particle relaxation in


  The origin of the universal optical conductivity form sigma(omega) ~
(1-e^(omega/T))/omega established in numerical model studies of doped
antiferromagnets and consistent with experiments on cuprates near optimal
doping is discussed. It is shown that such a behaviour appears quite generally
when the single-particle excitations are overdamped and their relaxation
follows the marginal Fermi liquid concept. Relation to recent ARPES experiments
is also discussed.

</DOC>
<DOC>
<DOCNO> 102392 </DOCNO>
Algebraic structures behind Hilbert schemes and wreath products


  In this paper we review various strikingly parallel algebraic structures
behind Hilbert schemes of points on surfaces and certain finite groups called
the wreath products. We explain connections among Hilbert schemes, wreath
products, infinite-dimensional Lie algebras, and vertex algebras. As an
application we further describe the cohomology ring structure of the Hilbert
schemes. We organize this exposition around several main points which have been
supported by various works on these subjects.

</DOC>
<DOC>
<DOCNO> 100728 </DOCNO>
On the Existence and Temperedness of Cusp Forms for SL(3,Z)


  We develop a partial trace formula which circumvents some technical
difficulties in computing the Selberg trace formula for the quotient
$SL_3({\Z})\backslash SL_3({\R})/SO_3({\R})$. As applications, we establish the
Weyl asymptotic law for the discrete Laplace spectrum and prove that almost all
of its cusp forms are tempered at infinity. The technique shows there are
non-lifted cusp forms on $SL_3({\Z})\backslash SL_3({\R})/SO_3({\R})$ as well
as non-self-dual ones. A self-contained description of our proof for
$SL_2({\Z})\backslash \U$ is included to convey the main new ideas. Heavy use
is made of truncation and the Maass-Selberg relations.

</DOC>
<DOC>
<DOCNO> 85505 </DOCNO>
The Brown-Henneaux's central charge from the path-integral boundary


  We derive Brown-Henneaux's commutation relation and central charge in the
framework of the path integral. If we use the leading part of the asymptotic
symmetry to derive the Ward-Takahashi identity, we can see the central charge
arises from the fact that the boundary condition of the path integral is not
invariant under the transformation.

</DOC>
<DOC>
<DOCNO> 12667 </DOCNO>
A Discotic Disguised as a Smectic: A Hybrid Columnar Bragg Glass


  We show that discotics, lying deep in the columnar phase, can exhibit an
x-ray scattering pattern which mimics that of a somewhat unusual smectic liquid
crystal. This exotic, new glassy phase of columnar liquid crystals, which we
call a ``hybrid columnar Bragg glass'', can be achieved by confining a columnar
liquid crystal in an anisotropic random environment of e.g., strained aerogel.
Long-ranged orientational order in this phase makes {\em single domain} x-ray
scattering possible, from which a wealth of information could be extracted. We
give detailed quantitative predictions for the scattering pattern in addition
to exponents characterizing anomalous elasticity of the system.

</DOC>
<DOC>
<DOCNO> 40047 </DOCNO>
Physics Prospects with an Intense Neutrino Experiment


  With new forthcoming intense neutrino beams, for the study of neutrino
oscillations, it is possible to consider other physics experiments that can be
done with these extreme neutrino fluxes available close to the source.

</DOC>
<DOC>
<DOCNO> 12842 </DOCNO>
Rotating Hele-Shaw cells with ferrofluids


  We investigate the flow of two immiscible, viscous fluids in a rotating
Hele-Shaw cell, when one of the fluids is a ferrofluid and an external magnetic
field is applied. The interplay between centrifugal and magnetic forces in
determining the instability of the fluid-fluid interface is analyzed. The
linear stability analysis of the problem shows that a non-uniform, azimuthal
magnetic field, applied tangential to the cell, tends to stabilize the
interface. We verify that maximum growth rate selection of initial patterns is
influenced by the applied field, which tends to decrease the number of
interface ripples. We contrast these results with the situation in which a
uniform magnetic field is applied normally to the plane defined by the rotating
Hele-Shaw cell.

</DOC>
<DOC>
<DOCNO> 120816 </DOCNO>
Interstellar Grains


  Our current understanding of interstellar dust is summarized at an
introductory level. Submicron-sized interstellar dust grains absorb and scatter
light, and reradiate the absorbed energy in the infrared. The grain population
spans a range of sizes, from molecules containing only tens of atoms, to
particles containing 10^{10} atoms. Most of the grain mass appears to be due to
two types of solid, in approximately equal amounts: amorphous silicate mineral,
and carbonaceous material. Approximately 2/3 of the interstellar carbon in
diffuse clouds is in solid form.
  Interstellar grains are important for many reasons: they obscure our view (in
a wavelength-dependent manner); the infrared emission from dust provides a
valuable probe of dense regions; and because dust grains play a central role in
interstellar chemistry, gas dynamics, and heating and cooling of interstellar
gas.

</DOC>
<DOC>
<DOCNO> 13416 </DOCNO>
Dynamical Scaling Properties of Electrons in Quantum Systems with


  We study the intricate relationships between the dynamical scaling properties
of electron wave packets and the multifractality of the eigenstates in quantum
systems. Numerical simulations for the Harper model and the Fibonacci chain
indicate that the root mean square displacement displays the scaling behavior
$r(t)\sim t^\beta$ with $\beta=D_2^\psi$, where $D_2^\psi$ is the correlation
dimension of the multifractal eigenstates. The equality can be generalized to
$d$-dimensional systems as $\beta=D_2^\psi/d$, as long as the electron motion
is ballistic in the effective $D_2^\psi$-dimensional space. This equality
should be replaced by $\beta<D_2^\psi/d$ if the motion is non-ballistic, as
supported by all known results.

</DOC>
<DOC>
<DOCNO> 11742 </DOCNO>
Entangled states in a Josephson charge qubit coupled to a


  We study the dynamics of a quantum superconducting circuit which is the
analogue of an atom in a high-Q cavity. The circuit consists of a Josephson
charge qubit coupled to a superconducting resonator. The charge qubit can be
treated as a two level quantum system whose energy separation is split by the
Josephson energy $E_j$. The superconducting resonator in our proposal is the
analogue of a photon box and is described by a quantum harmonic oscillator with
characteristic frequency $\omega_r$. The coupling between the charge qubit and
the resonator is realized by a coupling capacitance $C_c$. We have studied the
eigenstates as well as the dynamics of the quantum circuit. Interesting
phenomena occur when the Josephson energy equals the oscillator frequency,
$E_j=\hbar\omega_r$. Then the quantum circuit is described by entangled states.
We have deduced the time evolution of these states in the limit of weak
coupling between the charge qubit and the resonator. We found Rabi oscillations
of the excited charge qubit eigenstate. This effect is explained by the
spontaneous emission and re-absorption of a single photon in the
superconducting resonator.

</DOC>
<DOC>
<DOCNO> 170573 </DOCNO>
A New Formulation of Grover's Algorithm


  Withdrawn; replaced by longer, more detailed paper quant-ph/0010065.

</DOC>
<DOC>
<DOCNO> 150931 </DOCNO>
Graviton Scattering on D6 Branes with B Fields


  We consider systems of D6 branes in the presence of a nonzero $B$ field of
different ranks. We study the scattering of gravitons in the corresponding
supergravity backgrounds. We show that the nonzero $B$ field does not modify
the form of the scattering potential. The graviton scattering equation has two
solutions one normalizable and one non-normalizable. The normalizable solution
does not lead to an absorption, however the non-normalizable one does. We
analyse the absorption of gravitons by the branes and show that it is nonzero
in the decoupling limit. This result suggests that even in the presence of a
$B$ field the D6 branes worldvolume theory does not decouple from the bulk
gravity. For comparison we analyse the form of the scattering potential and
absorption for Dp branes with $p <5$ and for NS5 branes.

</DOC>
<DOC>
<DOCNO> 85304 </DOCNO>
Dynamical Rotational Instability at Low $T/W$


  Dynamical instability is shown to occur in differentially rotating polytropes
with N = 3.33 and $T/|W| \gtrsim 0.14$. This instability has a strong m=1 mode,
although the m=2, 3, and 4 modes also appear. Such instability may allow a
centrifugally-hung core to begin collapsing to neutron star densities on a
dynamical timescale. The gravitational radiation emitted by such unstable cores
may be detectable with advanced ground-based detectors, such as LIGO II. If the
instability occurs in a supermassive star, it may produce gravitational
radiation detectable by the space-based detector LISA.

</DOC>
<DOC>
<DOCNO> 10319 </DOCNO>
Nonlinear relaxation field in charged systems under high electric fields


  The influence of an external electric field on the current in charged systems
is investigated. The results from the classical hierarchy of density matrices
are compared with the results from the quantum kinetic theory. The kinetic
theory yields a systematic treatment of the nonlinear current beyond linear
response. To this end the dynamically screened and field-dependent
Lenard-Balescu equation is integrated analytically and the nonlinear relaxation
field is calculated. The classical linear response result known as Debye -
Onsager relaxation effect is only obtained if asymmetric screening is assumed.
Considering the kinetic equation of one specie the other species have to be
screened dynamically while the screening with the same specie itself has to be
performed statically. Different other approximations are discussed and
compared.

</DOC>
<DOC>
<DOCNO> 83379 </DOCNO>
Anaphora Resolution in Japanese Sentences Using Surface Expressions and


  Anaphora resolution is one of the major problems in natural language
processing. It is also one of the important tasks in machine translation and
man/machine dialogue. We solve the problem by using surface expressions and
examples. Surface expressions are the words in sentences which provide clues
for anaphora resolution. Examples are linguistic data which are actually used
in conversations and texts. The method using surface expressions and examples
is a practical method. This thesis handles almost all kinds of anaphora: i. The
referential property and number of a noun phrase ii. Noun phrase direct
anaphora iii. Noun phrase indirect anaphora iv. Pronoun anaphora v. Verb phrase
ellipsis

</DOC>
<DOC>
<DOCNO> 101464 </DOCNO>
Covariant first order differential calculus on quantum Euclidean spheres


  We study covariant differential calculus on the quantum spheres S_q^{N-1}
which are quantum homogeneous spaces with coactions of the quantum groups
O_q(N).
  The first part of the paper is devoted to first order differential calculus.
A classification result is proved which says that for N>=6 there exist exactly
two covariant first order differential calculi on S_q^{N-1} which satisfy the
classification constraint that the bimodule of one-forms is generated as a free
left module by the differentials of the generators of S_q^{N-1}. Both calculi
exist also for 3<=N<=5. The same calculi can be constructed using a method
introduced by Hermisson. In case N=3, the result is in accordance with the
known result by Apel and Schm\"udgen for the Podles sphere.
  In the second part, higher order differential calculus and symmetry are
treated. The relations which hold for the two-forms in the universal higher
order calculus extending one of the two first order calculi are given. A
"braiding" homomorphism is found. The existence of an upper bound for the order
of differential forms is discussed.

</DOC>
<DOC>
<DOCNO> 117962 </DOCNO>
OH Zeeman Magnetic Field Detections Toward Five Supernova Remnants Using


  We have observed the OH (1720 MHz) line in five galactic SNRs with the VLA to
measure their magnetic field strengths using the Zeeman effect. We detected all
12 of the bright ($S_{\nu} > 200$ mJy) OH (1720 MHz) masers previously detected
by Frail et al. (1996) and Green et al. (1997) and measured significant
magnetic fields (i.e. $ > 3\sigma$) in ten of them. Assuming that the
``thermal'' Zeeman equation can be used to estimate $\mid\vec{B}\mid$ for OH
masers, our estimated fields range from 0.2 to 2 mG. These magnetic field
strengths are consistent with the hypothesis that ambient molecular cloud
magnetic fields are compressed via the SNR shock to the observed values.
Magnetic fields of this magnitude exert a considerable influence on the
properties of the cloud with the magnetic pressures ($10^{-7} - 10^{-9}$ erg
cm$^{-3}$) exceeding the pressure in the ISM or even the thermal pressure of
the hot gas interior to the remnant. This study brings the number of galactic
SNRs with OH (1720 MHz) Zeeman detections to ten.

</DOC>
<DOC>
<DOCNO> 178439 </DOCNO>
Interrelation between the isoscalar octupole phonon and the


  The interrelation between the octupole phonon and the low-lying
proton-neutron mixed-symmetry quadrupole phonon in near-spherical nuclei is
investigated. The one-phonon states decay by collective E3 and E2 transitions
to the ground state and by relatively strong E1 and M1 transitions to the
isoscalar 2+ state. We apply the proton-neutron version of the Interacting
Boson Model including quadrupole and octupole bosons (sdf-IBM-2). Two F-spin
symmetric dynamical symmetry limits of the model, namely the vibrational and
the \gamma-unstable ones, are considered. We derive analytical formulae for
excitation energies as well as B(E1), B(M1), B(E2) and B(E3) values for a
number of transitions between low-lying states.

</DOC>
<DOC>
<DOCNO> 71314 </DOCNO>
Heavy Baryons and electromagnetic decays


  In this talk I review the theory of electromagnetic decays of the ground
state baryon multiplets with oneheavy quark, calculated using Heavy Hadron
Chiral Perturbation Theory. The M1 and E2 amplitudes for (S^{*}-> S gamma),
 (S^{*} -> T gamma) and (S -> T gamma)are separately analyzed. All M1
transitions are calculated up to O(1/\Lambda_\chi^2). The E2 amplitudes
contribute at the same order for (S^{*}-> S gamma), while for (S^{*} -> T
gamma) they first appear at O(1/(m_Q \Lambda_\chi^2))and for (S -> T gamma) are
completely negligible. Once the loop contributions is considered, relations
among different decay amplitudes are derived. Furthermore, one can obtain an
absolute prediction for the widths of Xi^{0'(*)}_c-> Xi^{0}_c gamma and
Xi^{-'(*)}_b-> Xi^{-}_b gamma.

</DOC>
<DOC>
<DOCNO> 100329 </DOCNO>
HyperK\"ahler Manifolds and Birational Transformations in dimension 4


  We show that any birational map between projective hyperK\"ahler manifolds of
dimension 4 is composed of a sequence of simple flops or elementary Mukai
transformations under the assumption that each irreducible component of the
indeterminacy of the birational map is normal.

</DOC>
<DOC>
<DOCNO> 170278 </DOCNO>
A unified approach for exactly solvable potentials in quantum mechanics


  We present a unified approach for solving and classifying exactly solvable
potentials. Our unified approach encompasses many well-known exactly solvable
potentials. Moreover, the new approach can be used to search systematically for
a new class of solvable potentials.

</DOC>
<DOC>
<DOCNO> 117064 </DOCNO>
Design, fabrication and measurement of the first rounded damped detuned


  As a joint effort in the JLC/NLC research program, we have developed a new
type of damped detuned accelerator structure with optimized round-shaped
cavities (RDDS). This paper discusses some important R&D aspects of the first
structure in this series (RDDS1). The design aspects covered are the cell
design with sub-MHz precision, HOM detuning, coupling and damping technique and
wakefield simulation. The fabrication issues covered are ultra-precision cell
machining with micron accuracy, assembly and diffusion bonding technologies to
satisfactorily meet bookshelf, straightness and cell rotational alignment
requirements. The measurements described are the RF properties of single
cavities and complete accelerator section, as well as wakefields from the ASSET
tests at SLAC. Finally, future improvements are also discussed.

</DOC>
<DOC>
<DOCNO> 117747 </DOCNO>
SAX J1810.8-2609: A New Hard X-ray Bursting Transient


  The transient X-ray source SAX J1810.8-2609 was discovered on 1998, March 10
with the Wide Field Cameras on board the BeppoSAX satellite, while observing
the Galactic Bulge in the 2-28 keV energy range. On March 11, a strong type-I
X-ray burst was detected with evidence of photospheric radius expansion. A
follow-up target of opportunity observation with the Narrow-Field Instruments
(NFI) was performed on March 11 and 12, for a total elapsed time of 8.51 x
10^{4} s. The wide band spectral data (0.1-200 keV) obtained with the NFI show
a remarkable hard X-ray spectrum detected up to ~200 keV, which can be
described by a power law with photon spectral index Gamma=1.96\pm0.04, plus a
soft component which is compatible with blackbody radiation of temperature
kT~0.5 keV.
  The detection of the type-I X-ray burst is a strong indication that the
compact object is a neutron star in a low mass X-ray binary system. Assuming
standard burst parameters and attributing the photospheric radius expansion to
near Eddington luminosity, we estimate a distance of ~5 kpc. The inferred 2-10
keV X-ray luminosity is ~ 9 x 10^{35} erg/s at the time of the discovery.

</DOC>
<DOC>
<DOCNO> 71363 </DOCNO>
Charm quark mass from QCD sum rules for the charmonium system


  In this work, the charm quark mass is obtained from a QCD sum rule analysis
of the charmonium system. In our investigation we include results from
nonrelativistic QCD at next-to-next-to-leading order. Using the pole mass
scheme, we obtain a value of $M_c=1.70\pm 0.13$ GeV for the charm pole mass.
The introduction of a potential-subtracted mass leads to an improved scale
dependence. The running ${\rm \bar{MS}}$-mass is then determined to be
$m_c(m_c) = 1.23 \pm 0.09$ GeV.

</DOC>
<DOC>
<DOCNO> 9108 </DOCNO>
Cholesteric Phase in Virus Suspensions


  We report measurements of the cholesteric pitch and twist elastic constant
$(K_{22})$ in monodisperse suspensions of the rod-like virus filamentous
bacteriophage {\it fd}. Measurements were taken for concentrations spanning the
entire cholesteric region at several ionic strengths and temperatures. In the
limit of high ionic strength the cholesteric pitch $(P_0)$ scales with
concentration (c) as $P_0 \propto c^{-1.66}$. As the ionic strength decreases
the scaling exponent systematically changes to lower values.

</DOC>
<DOC>
<DOCNO> 122460 </DOCNO>
Molecular Gas in the Powerful Radio Galaxies 3C~31 and 3C~264: Major or


  We report the detection of $^{12}$CO~($1 \to 0$) and $^{12}$CO~($2 \to 1$)
emission from the central regions ($\lesssim 5$--$10 {\rm kpc}$) of the two
powerful radio galaxies 3C~31 and 3C~264. Their individual CO emission exhibits
a double-horned line profile that is characteristic of an inclined rotating
disk with a central depression at the rising part of its rotation curve. The
inferred disk or ring distributions of the molecular gas is consistent with the
observed presence of dust disks or rings detected optically in the cores of
both galaxies. For a CO to H$_2$ conversion factor similar to that of our
Galaxy, the corresponding total mass in molecular hydrogen gas is $(1.3 \pm
0.2) \times 10^9 {\rm M_{\odot}}$ in 3C~31 and $(0.31 \pm 0.06) \times 10^9
{\rm M_{\odot}}$ in 3C~264. Despite their relatively large molecular-gas masses
and other peculiarities, both 3C~31 and 3C~264, as well as many other powerful
radio galaxies in the (revised) 3C catalog, are known to lie within the
fundamental plane of normal elliptical galaxies. We reason that if their gas
originates from the mergers of two gas-rich disk galaxies, as has been invoked
to explain the molecular gas in other radio galaxies, then both 3C~31 and
3C~264 must have merged a long time (a few billion years or more) ago but their
remnant elliptical galaxies only recently (last tens of millions of years or
less) become active in radio. Instead, we argue that the cannibalism of
gas-rich galaxies provides a simpler explanation for the origin of molecular
gas in the elliptical hosts of radio galaxies. Given the transient nature of
their observed disturbances, these galaxies probably become active in radio
soon after the accretion event when sufficient molecular gas agglomerates in
their nuclei.

</DOC>
<DOC>
<DOCNO> 8644 </DOCNO>
Duality and Anholonomy in Quantum Mechanics of 1D Contact Interactions


  We study systems with parity invariant contact interactions in one dimension.
The model analyzed is the simplest nontrivial one --- a quantum wire with a
point defect --- and yet is shown to exhibit exotic phenomena, such as strong
vs weak coupling duality and spiral anholonomy in the spectral flow. The
structure underlying these phenomena is SU(2), which arises as accidental
symmetry for a particular class of interactions.

</DOC>
<DOC>
<DOCNO> 13783 </DOCNO>
Aging Effect in Ceramic Superconductors


  A three-dimensional lattice of the Josephson junctions with a finite
self-conductance is employed to model ceramic superconductors. Using Monte
Carlo simulations it is shown that the aging disappears in the strong screening
limit. In the weeak screening regime aging is present even at low temperatures.
For intermediate values of the self-inductance aging occurs at intermediate
temperatures interval but is suppressed entirely at high and low temperatures.
Our results are in good agreement with experiments.

</DOC>
<DOC>
<DOCNO> 169767 </DOCNO>
An Experiment to Distinguish Between de Broglie-Bohm and Standard


  An experiment is suggested that is capable of distinguishing between the de
Broglie-Bohm theory and standard quantum mechanics.

</DOC>
<DOC>
<DOCNO> 72243 </DOCNO>
Neutrinos


  In these lectures the following topics are considered: historical remarks and
general properties, Dirac and Majorana neutrino masses, effective lagrangian
approach, the seesaw mechanism, the number of active left-hauded neutrino
species, the light neutrino mass matrix, the direct measurement of neutrino
masses, double beta decay, neutrino oscillations in vacuum and neutrino
oscillations in matter.

</DOC>
<DOC>
<DOCNO> 178656 </DOCNO>
The GDH sum rule for the deuteron


  As first topic, the GDH sume rule is discussed in the context of a more
general class of sum rules associated with the various contributions to the
total photoabsorption cross section for target and beam polarization. Then I
address the question of whether the GDH sum rule for the neutron can be
determined from the one for the deuteron. It appears that this will not be
possible in a simple manner. The spin response of the deuteron is calculated
including contributions from the photodisintegration channel and from coherent
and incoherent single pion production as well, and the GDH integral is
evaluated up to a photon energy of 550 MeV. The photodisintegration channel
converges fast enough and gives a large negative contribution, essentially from
the $^1S_0$ state near threshold and its absolute size is about the same than
the sum of proton and neutron GDH values. It is only partially cancelled by the
single pion production contribution. But the incoherent channel has not reached
convergence at 550 MeV.

</DOC>
<DOC>
<DOCNO> 10834 </DOCNO>
Many-spin effects and tunneling splittings in Mn12 magnetic molecules


  We calculate the tunneling splittings in a Mn$_{12}$ magnetic molecule taking
into account its internal many-spin structure. We discuss the precision and
reliability of these calculations and show that restricting the basis (limiting
the number of excitations taken into account) may lead to significant error
(orders of magnitude) in the resulting tunneling splittings for the lowest
energy levels. In this context, we address the usefulness of the single-spin
model for quantitative description of the tunneling in Mn$_{12}$. Analysis of
different applications of this model supports the point of view that the
predictions of this model are unreliable. We also discuss other possible
sources of errors, such as interactions not included into the model
Hamiltonian. We argue that the single-spin model is much more susceptible to
such errors than the many-spin model. Possible routes for further development
of the many-spin model of Mn$_{12}$ are discussed.

</DOC>
<DOC>
<DOCNO> 7941 </DOCNO>
Spin-triplet superconductivity in quasi-one dimension


  We consider a system with electron-phonon interaction, antiferromagnetic
fluctuations and disconnected open Fermi surfaces. The existence of odd-parity
superconductivity in this circumstance is shown for the first time. If it is
applied to the quasi-one-dimensional systems like the organic conductors
(TMTSF)_2X we obtain spin-triplet superconductivity with nodeless gap. Our
result is also valid in higher dimensions(2d and 3d).

</DOC>
<DOC>
<DOCNO> 152334 </DOCNO>
Domain walls in supersymmetric QCD: The taming of the zoo


  We provide a unified picture of the domain wall spectrum in supersymmetric
QCD with Nc colors and Nf flavors of quarks in the (anti-) fundamental
representation. Within the framework of the Veneziano-Yankielowicz-Taylor
effective Lagrangian, we consider domain walls connecting chiral symmetry
breaking vacua, and we take the quark masses to be degenerate. For Nf/Nc<1/2,
there is one BPS saturated domain wall for any value of the quark mass m. For
1/2=<Nf/Nc<1 there are two critical masses, m* and m**, which depend on the
number of colors and flavors only through the ratio Nf/Nc; if m<m*, there are
two BPS walls, if m*<m<m** there is one non-BPS wall, and if m>m** there is no
domain wall. We numerically determine m* and m** as a function of Nf/Nc, and we
find that m** approaches a constant value in the limit that this ratio goes to
one.

</DOC>
<DOC>
<DOCNO> 68396 </DOCNO>
Axial Anomaly and Polarized Radiative Decays


  We extend the approach of Dolgov and Zakharov to the axial anomaly to study
polarized radiative decays. We analyse the pattern of mass singularity
cancellation in the corresponding decay rates. We compare polarized and
unpolarized cases. The cancellation of the infrared and collinear singularities
is verified to all powers of the lepton mass for the $\pi^+$ and $Z^0$
polarized radiative decays.

</DOC>
<DOC>
<DOCNO> 72328 </DOCNO>
Confirmation of the existence of coherent orientations of quasar


  In order to verify the existence of coherent orientations of quasars
polarization vectors on very large scales, we have obtained new polarization
measurements for a sample of quasars located in a given region of the
three-dimensional Universe where the range of polarization position angles was
predicted in advance. For this new sample, the hypothesis of uniform
distribution of polarization position angles may be rejected at the 1.8%
significance level on the basis of a simple binomial test. This result provides
an independent confirmation of the existence of alignments of quasar
polarization vectors on very large scales. In total, out of 29 polarized
quasars located in this region of the sky, 25 have their polarization vectors
coherently oriented. This alignment occurs at redshifts 1-2 suggesting the
presence of correlations in objects or fields on Gpc scales. More global
statistical tests applied to the whole sample of polarized quasars distributed
all over the sky confirm that polarization vectors are coherently oriented in a
few groups of 20-30 quasars. Some constraints on the phenomenon are also
derived. Considering more particularly the quasars in the selected region of
the sky, we found that their polarization vectors are roughly parallel to the
plane of the Local Supercluster. But the polarization vectors of objects along
the same line of sight at lower redshifts are not accordingly aligned. We also
found that the known correlations between quasar intrinsic properties and
polarization are not destroyed by the alignment effect. Several possible
mechanisms are discussed, but the interpretation of this orientation effect
remains puzzling.

</DOC>
<DOC>
<DOCNO> 71498 </DOCNO>
Measuring the Higgs Branching Fraction into two Photons at Future Linear


  We examine the prospects for measuring the \gaga branching fraction of a
Standard Model-like Higgs boson with a mass of 120 GeV at the future TESLA
linear \ee collider, assuming an integrated luminosity of 1 ab$^{-1}$ and
center-of-mass energies of 350 GeV and 500 GeV. The Higgs boson is produced in
association with a fermion pair via the Higgsstrahlung process \ee $\to ZH$,
with $Z \to$ \qq or \nn, or the WW fusion reaction $e^+e^- \to \nu_e
\bar{\nu_e} H$. A relative uncertainty on BF(\hgg) of~16% can be achieved in
unpolarized \ee collisions at $\sqrt{s}$=~500 GeV, while for $\sqrt{s}$=~350
GeV the expected precision is slightly poorer. With appropriate initial state
polarizations $\Delta$BF(\hgg)/BF(\hgg) can be improved to 10%. If this
measurement is combined with the expected error for the total Higgs width, a
precision of 10% on the \gaga Higgs boson partial width appears feasible.

</DOC>
<DOC>
<DOCNO> 152575 </DOCNO>
On Curvature Expansion of Higher Spin Gauge Theory


  We examine the curvature expansion of a the field equations of a
four-dimensional higher spin gauge theory extension of anti-de Sitter gravity.
The theory contains massless particles of spin 0,2,4,... that arise in the
symmetric product of two spin 0 singletons. We cast the curvature expansion
into manifestly covariant form and elucidate the structure of the equations and
observe a significant simplification.

</DOC>
<DOC>
<DOCNO> 117444 </DOCNO>
The Most Distant X-ray Clusters and the Evolution of their Space Density


  We briefly review our current knowledge of the space density of distant X-ray
clusters as measured by several ROSAT serendipitous surveys. We compare old and
new determinations of the cluster X-ray Luminosity Function (XLF) at increasing
redshifts, addressing the controversial issue of the evolution of its high end.
We use complete subsamples, drawn from the ROSAT Deep Cluster Survey (RDCS), to
quantify the statistical significance of the XLF evolution out to z ~1. A
consistent observational picture emerges in which the bulk of the cluster
population shows no significant evolution out to z ~1, whereas the most
luminous systems (L_x >~ L* [0.5-2 keV] =~ 5x10^44 erg/s) were indeed rarer, at
least at z >0.5, in keeping with the original findings of the EMSS. We also
report on the recent spectroscopic identification of four clusters in the RDCS
lying beyond z =1, the most distant X-ray clusters known to date, which set an
interesting lower limit on the space density of clusters at z >1.

</DOC>
<DOC>
<DOCNO> 68782 </DOCNO>
Radion effective potential in the Brane-World


  We show that in brane-world scenarios with warped extra dimensions, the
Casimir force due to bulk matter fields may be sufficient to stabilize the
radion field $\phi$. In particular, we calculate one loop effective potential
for $\phi$ induced by bulk gravitons and other possible massless bulk fields in
the Randall-Sundrum background. This potential has a local extremum, which can
be a maximum or a minimum depending on the detailed bulk matter content. If the
parameters of the background are chosen so that the hierarchy problem is solved
geometrically, then the radion mass induced by Casimir corrections is
hierarchycally smaller than the $TeV$. Hence, in this important case, we must
invoke an alternative mechanism (classical or nonperturbative) which gives the
radion a sizable mass, to make it compatible with observations.

</DOC>
<DOC>
<DOCNO> 118462 </DOCNO>
Relativistic Approach to Isoscalar Giant Resonances in 208Pb


  We calculate the longitudinal response of 208Pb using a relativistic
random-phase approximation to three different parameterizations of the Walecka
model with scalar self-interactions. From a nonspectral calculation of the
response-that automatically includes the mixing between positive- and
negative-energy states-we extract the distribution of strength for the
isoscalar monopole, dipole, and high-energy octupole resonances. We employ a
consistent formalism that uses the same interaction in the calculation of the
ground state as in the calculation of the response. As a result, the
conservation of the vector current is strictly maintained throughout the
calculation. Further, at small momentum transfers the spurious dipole
strength-associated with the uniform translation of the center-of-mass-gets
shifted to zero excitation energy and is cleanly separated from the sole
remaining physical fragment located at an excitation energy of about 24 MeV; no
additional dipole strength is observed. The best description of the collective
modes is obtained using a ``soft'' parameterization having a compression
modulus of K=224 MeV.

</DOC>
<DOC>
<DOCNO> 10694 </DOCNO>
Symmetry and designability for lattice protein models


  Native protein folds often have a high degree of symmetry. We study the
relationship between the symmetries of native proteins, and their
designabilities -- how many different sequences encode a given native
structure. Using a two-dimensional lattice protein model based on
hydrophobicity, we find that those native structures that are encoded by the
largest number of different sequences have high symmetry. However only certain
symmetries are enhanced, e.g. x/y-mirror symmetry and $180^o$ rotation, while
others are suppressed. If it takes a large number of mutations to destabilize
the native state of a protein, then, by definition, the state is highly
designable. Hence, our findings imply that insensitivity to mutation implies
high symmetry. It appears that the relationship between designability and
symmetry results because protein substructures are also designable. Native
protein folds may therefore be symmetric because they are composed of repeated
designable substructures.

</DOC>
<DOC>
<DOCNO> 120458 </DOCNO>
ASCA Observations of Three Shakhbazyan's Compact Groups of Galaxies


  X-ray observations of three Shakhbazyan's Compact Groups of Galaxies, SCGG
202, SCGG 205, and SCGG 223, are presented for the first time. Extended X-ray
emission was detected from SCGG 202 and SCGG 223 with 0.5-2 keV luminosity of
1E42 erg/s and 3E42 erg/s (for H_0 = 75 km/s/Mpc), respectively, while no
significant emission was detected from SCGG 205 with an upper limit of 0.7E42
erg/s. The X-ray spectra of SCGG 202 and SCGG 223 can be described with
thin-thermal plasma emission with temperature about 1 keV. X-ray properties of
SCGG 202 and SCGG 223 are in good agreement with those of other known groups of
galaxies, proving the physical nature of their grouping.

</DOC>
<DOC>
<DOCNO> 14007 </DOCNO>
Mirror symmetry breaking through an internal degree of freedom leading


  We analyze here the minimal conditions for directional motion (net flow in
phase space) of a molecular motor placed on a mirror-symmetric environment and
driven by a center-symmetric and time-periodic force field. The complete
characterization of the deterministic limit of the dissipative dynamics of
several realizations of this minimal model, reveals a complex structure in the
phase diagram in parameter space, with intertwined regions of pinning (closed
orbits) and directional motion. This demonstrates that the mirror-symmetry
breaking which is needed for directional motion to occur, can operate through
an internal degree of freedom coupled to the translational one.

</DOC>
<DOC>
<DOCNO> 118115 </DOCNO>
ChaMP and the High Redshift Quasars in X-rays


  Chandra X-ray Observatory, (formerly known as AXAF), will observe down to the
flux limit of 2\times 10^{-16} erg~s^{-1} cm^{-2}. In its first year of
operation Chandra's CCD detectors will observe over 1500 quasars
serendipitously in the soft (0.5--3.5 keV) band. Over 200 quasars will be
detected in X-rays in the redshift range 3<z<4 and over 400 quasars in 2<z<3.
This will enable us to determine the high redshift X-ray luminosity function.
This is the contribution by unabsorbed sources only. The total numbers would be
larger by about 60%

</DOC>
<DOC>
<DOCNO> 123061 </DOCNO>
Optical/Infrared Survey of Galaxy Clusters


  In this contribution the ongoing effort to build a statistical sample of
clusters of galaxies over a wide range of redshifts to study the evolution of
clusters and member galaxies is reviewed. The starting point for this project
has been the list of candidate clusters identified from the I-band EIS-WIDE
survey data. Since the completion of this survey, new optical/infrared
observations have become available and have been used to confirm some of these
candidates using the photometric data alone or in combination with the results
of follow-up spectroscopic observations. Our preliminary results show that the
yield of real physical associations from the original catalog is conservatively
>60% and that a large sample of clusters in the southern hemisphere, extending
to high-redshifts, is within reach.

</DOC>
<DOC>
<DOCNO> 170499 </DOCNO>
Homodyne Bell's inequalities for entangled mesoscopic superpositions


  We present a scheme for demonstrating violation of Bell's inequalities using
a spin-1/2 system entangled with a pair of classically distinguishable wave
packets in a harmonic potential. In the optical domain, such wave packets can
be represented by coherent states of a single light mode. The proposed scheme
involves standard spin-1/2 projections and measurements of the position and the
momentum of the harmonic oscillator system, which for a light mode can be
realized by means of homodyne detection. We discuss effects of imperfections,
including non-unit efficiency of the homodyne detector, and point out a close
link between the visibility of interference and violation of Bell's
inequalities in the described scheme.

</DOC>
<DOC>
<DOCNO> 72113 </DOCNO>
PYTHIA Status Report


  Recent improvements in the PYTHIA event generator are summarized: new hard
subprocesses, gamma*-gamma* physics, QCD final-state showers, and more.

</DOC>
<DOC>
<DOCNO> 14146 </DOCNO>
Hybridization Mechanism for Cohesion of Cd-based Quasicrystals


  Cohesion mechanism of cubic approximant crystals of newly discovered binary
quasicrystals, Cd$_6$M (M=Yb and Ca), are studied theoretically. It is found
that stabilization due to alloying is obtained if M is an element with
low-lying unoccupied $d$ states. This leads to conclusion that the cohesion of
the Cd-based compounds is due to the hybridization of the $d$ states of Yb and
Ca with a wide $sp$ band. %unlike known stable quasicrystals without transition
elements %such as Al-Li-Cu and Zn-Mg-RE (RE:rare earth). Although a diameter of
the Fermi sphere coincides with the strong Bragg peaks for Cd-Yb and Cd-Ca, the
Hume-Rothery mechanism does not play a principal role in the stability because
neither distinct pseudogap nor stabilization due to alloying is obtained for
isostructural Cd-Mg. In addition to the electronic origin, matching of the
atomic size is very crucial for the quasicrystal formation of the Cd-based
compounds. It is suggested that the glue atoms, which do not participate in the
icosahedral cluster, play an important role in stabilization of the compound.

</DOC>
<DOC>
<DOCNO> 117615 </DOCNO>
A continuous low star formation rate in IZw 18 ?


  Deep long-slit spectroscopic observations of the blue compact galaxy IZw 18
obtained with the CFH 3.6 m Telescope are presented. The very low value of
oxygen abundance previously reported is confirmed and a very homogeneous
abundance distribution is found (no variation larger than 0.05 dex) over the
whole ionized region. We concur with Tenorio-Tagle (1996) and Devost et al.
(1997) that the observed abundance level cannot result from the material
ejected by the stars formed in the current burst, and propose that the observed
metals were formed in a previous star formation episode. Metals ejected in the
current burst of star formation remain most probably hidden in a hot phase and
are undetectable using optical spectroscopy. We discuss different scenarios of
star formation in IZw 18. Combining various observational facts, for instance
the faint star formation rate observed in low surface brightness galaxies van
Zee et al. (1997), it is proposed that a low and continuous rate of star
formation occurring during quiescent phases between bursts could be a
significant source of metal enrichment of the interstellar medium.

</DOC>
<DOC>
<DOCNO> 101418 </DOCNO>
Relative Yamabe Invariant


  We define a relative Yamabe invariant of a smooth manifold with given
conformal class on its boundary. In the case of empty boundary the invariant
coincides with the classic Yamabe invariant. We develop approximation technique
which leads to gluing theorems of two manifolds along their boundaries for the
relative Yamabe invariant. We show that there are many examples of manifolds
with both positive and non-positive relative Yamabe invariants.

</DOC>
<DOC>
<DOCNO> 170195 </DOCNO>
Quantum Recurrences: Probe to study Quantum Chaos


  We study the phase space of periodically modulated gravitational cavity by
means of quantum recurrence phenomena. We report that the quantum recurrences
serve as a tool to connect phase space of the driven system with spectrum in
quantum domain. With the help of quantum recurrences we investigate the
quasi-energy spectrum of the system for a certain fixed modulation strength. In
addition, we study transition of spectrum from discrete to continuum as a
function of modulation strength.

</DOC>
<DOC>
<DOCNO> 102383 </DOCNO>
The Density of States and the Spectral Shift Density of Random


  In this article we continue our analysis of Schroedinger operators with a
random potential using scattering theory. In particular the theory of Krein's
spectral shift function leads to an alternative construction of the density of
states in arbitrary dimensions. For arbitrary dimension we show existence of
the spectral shift density, which is defined as the bulk limit of the spectral
shift function per unit interaction volume. This density equals the difference
of the density of states for the free and the interaction theory. This extends
the results previously obtained by the authors in one dimension. Also we
consider the case where the interaction is concentrated near a hyperplane.

</DOC>
<DOC>
<DOCNO> 151188 </DOCNO>
Entangled Simultaneous Measurement and Elementary Particle


  We propose that the principles of relativistic quantum mechanics are
incomplete for simultaneous measurement of non-commuting operators. Consistent
joint measurement of incompatible observables at a single point in space-time
requires that the system be in an entangled state with vacuum meters. We
suggest that entagled simultaneous mesurement for noncommuting observables is
the basis for the observed fermionic multiplets. This generalizes the standard
spin representations for particles arising from Lorentz invariance. We show
that operator entanglement for all quantum observables in the Poincare algebra,
coupled with Fermi-Dirac statistics, mandates six fermions. We propose that the
quark and lepton generations form a super-structure of the Poincare algebra
based on the principles of entangled simultaneity. Mathematically, that
super-structure is known as a Naimark extension. The required entanglement
between particle generations for left-handed quarks is observed in the
Cabbibo-Kobayashi-maskawa matrix. We show that the Naimark-extended von Neumann
lattice is ditributive, thereby suggesting the principle of entangled
simultaneity as a mechanism to avoid quantum non-locality. Keywords: enatangled
simultaneous quantum measurement, Naimark extension, Lepton/quark generations.
PACS Number: 03.65.BZ

</DOC>
<DOC>
<DOCNO> 117467 </DOCNO>
The modified dynamics is conducive to galactic warp formation


  There is an effect in the modified dynamics (MOND) that is conducive to
formation of warps. Because of the nonlinearity of the theory the internal
dynamics of a galaxy is affected by a perturber over and above possible tidal
effects. For example, a relatively distant and light companion or the mean
influence of a parent cluster, with negligible tidal effects, could still
produce a significant warp in the outer part of a galactic disk. We present
results of numerical calculations for simplified models that show, for
instance, that a satellite with the (baryonic) mass and distance of the
Magellanic clouds can distort the axisymmetric field of the Milky Way enough to
produce a warp of the magnitude (and position) observed. Details of the warp
geometry remain to be explained: we use a static configuration that can produce
only warps with a straight line of nodes. In more realistic simulations one
must reckon with the motion of the perturbing body, which sometimes occurs on
time scales not much longer than the response time of the disk.

</DOC>
<DOC>
<DOCNO> 151766 </DOCNO>
Z_N x Z_M orientifolds with and without discrete torsion


  We discuss compact four-dimensional Z_N x Z_M type IIB orientifolds. We take
a systematic approach to classify the possible models and construct them
explicitely. The supersymmetric orientifolds of this type have already been
constructed some time ago. We find that there exist several consistent
orientifolds for each of the discrete groups Z_2 x Z_2, Z_2 x Z_4, Z_4 x Z_4,
Z_2 x Z_6, Z_2 x Z_6' and Z_6 x Z_6 if anti-D5-branes are introduced.
Supersymmetry is broken by the open strings ending on antibranes. The rank of
the gauge group is reduced by a factor two if the underlying orbifold space has
discrete torsion.

</DOC>
<DOC>
<DOCNO> 13963 </DOCNO>
New results for the epsilon-expansion of certain one-, two- and


  For certain dimensionally-regulated one-, two- and three-loop diagrams,
problems of constructing the epsilon-expansion and the analytic continuation of
the results are studied. In some examples, an arbitrary term of the
epsilon-expansion can be calculated. For more complicated cases, only a few
higher terms in epsilon are obtained. Apart from the one-loop two- and
three-point diagrams, the examples include two-loop (mainly on-shell)
propagator-type diagrams and three-loop vacuum diagrams. As a by-product, some
new relations involving Clausen function, generalized log-sine integrals and
certain Euler--Zagier sums are established, and some useful results for the
hypergeometric functions of argument 1/4 are presented.

</DOC>
<DOC>
<DOCNO> 8510 </DOCNO>
Wannier Functions for Lattices in a Magnetic Field II: Extensions to


  This paper extends earlier work on the definition of Wannier functions for
Bloch electrons in a magnetic field. Extensions to irrational as well as
rational magnetic fields are defined, and their properties investigated. The
results are used to give a generalisation of the Peierls effective Hamiltonian
which is valid when the magnetic flux per unit cell is close to any rational
number.

</DOC>
<DOC>
<DOCNO> 118040 </DOCNO>
Delta Scuti Stars in Stellar Systems: the interest of HD 220392 and HD


  The very wide double star CCDM 23239-5349 is an interesting study case of a
pulsating star within a common origin pair or wide binary. Both stars are
located in the Delta Scuti instability strip. Based on data obtained at La
Silla (Chile), at the Swiss 0.7m and the ESO 0.5m telescopes, we found two
periodicities of about 4.7 and 5.5 cycles per day (cpd) with amplitudes of
0.014 and 0.011 mag, respectively, for HD 220392, the brightest member of the
system. The most dominant periodicity was also detected in the Hipparcos Epoch
Photometry data. A similar period search on the (smaller) dataset obtained for
the 1 mag fainter B-component, HD 220391, however shows no periodic behaviour
with an amplitude significantly above the noise level of the data (about 0.006
mag).

</DOC>
<DOC>
<DOCNO> 118393 </DOCNO>
Evolution of lithium in solar-type stars: clues from intermediate age


  We present Li abundances for 14 solar-type stars in the intermediate age (~ 2
Gyr) clusters IC 4651 and NGC 3680. The log n(Li) vs. effective temperature
distributions are compared with those of the similar age cluster NGC 752, of
the younger Hyades (600 Myr) and of the older M 67 (4.5 Gyr) and NGC 188 (6-7
Gyr) clusters. Neither IC 4651 nor NGC 3680 show the dispersion in Li which is
observed in M 67. The 2 Gyr clusters have very similar Li vs. effective
temperature distributions; in addition, stars in the upper envelope of the M 67
distribution have the same Li content as stars in the 2 Gyr clusters,
suggesting that either they have not suffered any significant depletion between
2 and 4.5 Gyr or they had a much slower Li depletion. Mechanisms that lead to
Li depletion on the main sequence are discussed in the light of these
observations. None of the existing models seem to reproduce well the observed
features.

</DOC>
<DOC>
<DOCNO> 102118 </DOCNO>
Pseudoholomorphic curves and the symplectic isotopy problem


  The deformation problem for pseudoholomorphic curves and related geometrical
properties of the total moduli space of pseudoholomorphic curves are studied. A
sufficient condition for the saddle point property of the total moduli space is
established. The local symplectic isotopy problem is formulated and solved for
the case of imbedded pseudoholomorphic curves. It is shown that any two
symplectically imbedded surfaces Sigma_0, Sigma_1 in CP^2 of the same degree
d\le 6 are symplectically isotopic.

</DOC>
<DOC>
<DOCNO> 150505 </DOCNO>
Confinement and the AdS/CFT Correspondence


  We study the thermodynamics of the confined and unconfined phases of
superconformal Yang-Mills in finite volume and at large N using the AdS/CFT
correspondence. We discuss the necessary conditions for a smooth phase
crossover and obtain an N-dependent curve for the phase boundary.

</DOC>
<DOC>
<DOCNO> 84878 </DOCNO>
Addemdum to: ''The Mathematical Structure of Quantum Superspace as a


  In this paper we improve the results of sec. VI of paper [M. Castagnino,
Phys. Rev. D 57, 750 (1998)] by considering that the main source of entropy
production are the photospheres of the stars.

</DOC>
<DOC>
<DOCNO> 169603 </DOCNO>
Quantum limit of optical magnetometry in the presence of ac-Stark shifts


  We analyze systematic (classical) and fundamental (quantum) limitations of
the sensitivity of optical magnetometers resulting from ac-Stark shifts. We
show that in contrast to absorption-based techniques, the signal reduction
associated with classical broadening can be compensated in magnetometers based
on phase measurements using electromagnetically induced transparency (EIT).
However due to ac-Stark associated quantum noise the signal-to-noise ratio of
EIT-based magnetometers attains a maximum value at a certain laser intensity.
This value is independent on the quantum statistics of the light and defines a
standard quantum limit of sensitivity. We demonstrate that an EIT-based optical
magnetometer in Faraday configuration is the best candidate to achieve the
highest sensitivity of magnetic field detection and give a detailed analysis of
such a device.

</DOC>
<DOC>
<DOCNO> 7846 </DOCNO>
Stabilization of A-type layered antiferromagnetic phase in LaMnO_3 by


  It is shown that the layered antiferromagnetic order in stoechiometric
LaMnO_3 cannot be understood purely from electronic interactions. On the
contrary, it mainly results from strong cooperative Jahn-Teller deformations.
Those involve a compression of the Mn-O octahedron along the c-axis (mode Q_3 <
0), while alternate Jahn-Teller deformations occur in the ab-plane (mode Q_2).
These deformations stabilize a certain type of orbital ordering. The resulting
superexchange couplings are calculated by exact diagonalization, taking into
account both e_g and t_{2g} orbitals. The main result is that antiferromagnetic
(ferromagnetic) coupling along the c-direction (ab-planes) can be understood
only if the Jahn-Teller energy is much larger than the superexchange couplings,
which is consistent with experiments. This mechanism contrasts with that based
on weak Jahn-Teller coupling which instead predicts elongation along the c-axis
(Q_3 > 0). The crucial role of the deformation anisotropy Q_2/Q_3 is also
emphasized.

</DOC>
<DOC>
<DOCNO> 101142 </DOCNO>
About interpolation of subspaces of reaarangement invariant spaces


  The Rademacher series in rearrangement invariant function spaces "closed" to
the space L_\infty are considered. In terms of interpolation theory of
operators a correspondence between such spaces and spaces of coefficients
generated by them is stated. It is proved that this correspondence is
one-to-one. Some examples and applications are presented.

</DOC>
<DOC>
<DOCNO> 71264 </DOCNO>
Tests for Coherence in Neutral B Meson Decays


  A density-matrix method for the study of tagged states of neutral B mesons
with arbitrary coherence properties is applied to several examples, including
$e^+ e^-$ production both at and above the $\Upsilon(4S)$ resonance, and
hadronic production. In the absence of coherence the only term modulating the
exponential decay of a neutral B meson behaves as $\cos \Delta m t$, while a
$\sin \Delta m t$ modulation is a signal of partial or full coherence. Decays
to CP eigenstates are needed to fully specify the density matrix. We relate
these results to more familiar expressions for the cases of the $\Upsilon(4S)$
and incoherent production.

</DOC>
<DOC>
<DOCNO> 67649 </DOCNO>
Gribov's Equation for the Green Function of Light Quarks


  Gribov's scenario of supercritical charges in QCD is investigated. We perform
a numerical study of the corresponding equation for the Green function of light
quarks. This is done in an approximation which neglects all pion contributions.
Different types of solutions in the Euclidean region are discussed and the mass
function of the quark is calculated. The solutions of the equation are shown to
have a qualitatively different behaviour if the strong coupling constant
alpha_s exceeds a critical value alpha_c = 0.43 in the infrared region. Chiral
symmetry breaking is found to occur at supercritical coupling. The analytic
structure of the solutions is investigated. Earlier results obtained by Gribov
are confirmed and extended.

</DOC>
<DOC>
<DOCNO> 72120 </DOCNO>
The Standard Model Higgs in $\gamma \gamma$ Collisions


  For a Higgs boson below the $W^\pm$ threshold, the $\gamma \gamma$ collider
option of a future linear $e^+ e^-$ machine is compelling. In this case one can
measure the ``gold-plated'' loop induced $\Gamma (H \longrightarrow \gamma
\gamma)$ partial width to high precision, testing various extensions of the
Standard Model. With recent progress in the expected $\gamma \gamma$ luminosity
at TESLA, we find that for a Higgs of 115 GeV a statistical accuracy of the two
photon partial width of 1.4 % is possible. The total width depends thus solely
on the accuracy of $BR(H \longrightarrow \gamma \gamma)$ and is of ${\cal O}
(10 %)$.

</DOC>
<DOC>
<DOCNO> 12430 </DOCNO>
AC resistivity of d-wave ceramic superconductors


  We model d-wave ceramic superconductors with a three-dimensional lattice of
randomly distributed $\pi$ Josephson junctions with finite self-inductance. The
linear and nonlinear ac resistivity of the d-wave ceramic superconductors is
obtained as function of temperature by solving the corresponding Langevin
dynamical equations. We find that the linear ac resistivity remains finite at
the temperature $T_p$ where the third harmonics of resistivity has a peak. The
current amplitude dependence of the nonlinear resistivity at the peak position
is found to be a power law. These results agree qualitatively with experiments.
We also show that the peak of the nonlinear resistivity is related to the onset
of the paramagnetic Meissner effect which occurs at the crossover temperature
$T_p$, which is above the chiral glass transition temperature $T_{cg}$.

</DOC>
<DOC>
<DOCNO> 68877 </DOCNO>
Renormalizability and model independent description of Z' signals at low


  Model independent search for signals of heavy Z' gauge bosons in low-energy
four-fermion processes is analyzed. It is shown that the renormalizability of
the underlying theory containing Z', formulated as a scattering in the field of
heavy virtual states, can be implemented in specific relations between
different processes. Considering the two-Higgs-doublet model as the low-energy
basis theory, the two types of Z' interactions with light particles are found
to be compatible with the renormalizability. They are called the Abelian and
the "chiral" couplings. Observables giving possibility to uniquely detect Z' in
both cases are introduced.

</DOC>
<DOC>
<DOCNO> 99839 </DOCNO>
Orlicz-Pettis polynomials on Banach spaces


  We introduce the class of Orlicz-Pettis polynomials between Banach spaces,
defined by their action on weakly unconditionally Cauchy series. We give a
number of equivalent definitions, examples and counterexamples which highlight
the differences between these polynomials and the corresponding linear
operators.

</DOC>
<DOC>
<DOCNO> 117902 </DOCNO>
Discovery of an Obscured Broad Line Region in the High Redshift Radio


  This paper presents infrared spectra taken with the newly commissioned
NIRSPEC spectrograph on the Keck II Telescope of the High Redshift Radio Galaxy
MRC 2025-218 (z=2.63) These observations represent the deepest infrared spectra
of a radio galaxy to date and have allowed for the detection of Hbeta, [OIII]
(4959/5007), [OI] (6300), Halpha, [NII] (6548/6583) and [SII] (6716/6713). The
Halpha emission is very broad (FWHM = 9300 km/s) and luminous (2.6x10^44
ergs/s) and it is very comparable to the line widths and strengths of radio
loud quasars at the same redshift. This strongly supports AGN unification
models linking radio galaxies and quasars, although we discuss some of the
outstanding differences. The [OIII] (5007) line is extremely strong and has
extended emission with large relative velocities to the nucleus. We also derive
that if the extended emission is due to star formation, each knot has a star
formation rate comparable to a Lyman Break Galaxy at the same redshift.

</DOC>
<DOC>
<DOCNO> 12034 </DOCNO>
Comment on the intermediate vortex liquid phase in extreme type-II


  It is shown that disentangled vortex liquid can be a true thermodynamic phase
of type-II superconductors in spite of the absense of supercurrent in the
direction parallel to the magnetic field.

</DOC>
<DOC>
<DOCNO> 123020 </DOCNO>
Evidence for a Supermassive Black Hole in the S0 Galaxy NGC 3245


  The S0 galaxy NGC 3245 contains a circumnuclear disk of ionized gas and dust
with a radius of 1.1" (110 pc), making it an ideal target for dynamical studies
with the Hubble Space Telescope. We have obtained spectra of the nuclear disk
with the Space Telescope Imaging Spectrograph, using an 0.2"-wide slit at five
parallel positions. Measurements of the H-alpha and [N II] emission lines are
used to map out the kinematic structure of the disk in unprecedented detail.
The data reveal a rotational velocity field with a steep velocity gradient
across the innermost 0.4". We construct dynamical models for a thin gas disk in
circular rotation, using HST optical images to map out the gravitational
potential due to stars. The H-alpha+[N II] surface brightness measured from an
HST narrow-band image is folded into the models, and we demonstrate that many
of the apparent small-scale irregularities in the observed velocity curves are
the result of the patchy distribution of emission-line surface brightness. A
central dark mass of (2.1+/-0.5)x10^8 solar masses is required for the models
to reproduce the steep central velocity gradient. This value for the central
mass is consistent with recently discovered correlations between black-hole
mass and bulge velocity dispersion.

</DOC>
<DOC>
<DOCNO> 69825 </DOCNO>
Analytical Behaviour of Positronium Decay Amplitudes


  Positronium annihilation amplitudes that are computed by assuming a
factorization approximation with on-shell intermediate leptons do not exhibit
good analytical behaviour. Using dispersion techniques, we find new
contributions that interfere with the known results to restore analytical
properties. Those new amplitudes which cannot be obtained using standard
factorized amplitude formalism, contribute at order alpha^2. Therefore they
have to be evaluated before any theoretical conclusion can be drawn upon the
orthopositronium lifetime puzzle.

</DOC>
<DOC>
<DOCNO> 8878 </DOCNO>
Pseudo--epsilon expansion of six--loop renormalization group functions


  Six-loop massive scheme renormalization group functions of a d=3-dimensional
cubic model (J.M. Carmona, A. Pelissetto, and E. Vicari, Phys. Rev. B vol. 61,
15136 (2000)) are reconsidered by means of the pseudo-epsilon expansion. The
marginal order parameter components number N_c=2.862(5) as well as critical
exponents of the cubic model are obtained. Our estimate N_c<3 leads in
particular to the conclusion that all ferromagnetic cubic crystals with three
easy axis should undergo a first order phase transition.

</DOC>
<DOC>
<DOCNO> 84982 </DOCNO>
The exact cosmological solution to the dynamical equations for the


  Quantum geometrodynamics in extended phase space describes phenomenologically
the integrated system ``a physical object + observation means (a gravitational
vacuum condensate)''. The central place in this version of QGD belongs to the
Schrodinger equation for a wave function of the Universe. An exact solution to
the ``conditionally-classical'' set of equations in extended phase space for
the Bianchi-IX model and the appropriate solution to the Schrodinger equation
are considered. The physical adequacy of the obtained solutions to existing
concepts about possible cosmological scenarios is demonstrated. The
gravitational vacuum condensate is shown to be a cosmological evolution factor.

</DOC>
<DOC>
<DOCNO> 83439 </DOCNO>
Computational Geometry Column 40


  It has recently been established by Below, De Loera, and Richter-Gebert that
finding a minimum size (or even just a small) triangulation of a convex
polyhedron is NP-complete. Their 3SAT-reduction proof is discussed.

</DOC>
<DOC>
<DOCNO> 170004 </DOCNO>
Radiation Pressure Induced Einstein-Podolsky-Rosen Paradox


  We demonstrate the appearance of Einstein-Podolsky-Rosen (EPR) paradox when a
radiation field impinges on a movable mirror. The, the possibility of a local
realism test within a pendular Fabry-Perot cavity is shown to be feasible.

</DOC>
<DOC>
<DOCNO> 68840 </DOCNO>
The Reach of the CERN Large Hadron Collider for Gauge-Mediated


  We examine signals for sparticle production at the CERN Large Hadron Collider
(LHC) within the framework of gauge mediated supersymmetry breaking models with
a low SUSY breaking scale for four different model lines, each of which leads
to qualitatively different signatures. We first examine the reach of the LHC
via the canonical E_T^miss and multilepton channels that have been advocated
within the mSUGRA framework. Next, we examine special features of each of these
model lines that could serve to further enhance the SUSY signal over Standard
Model backgrounds. We use ISAJET to evaluate the SUSY reach of experiments at
the LHC. We find that the SUSY reach, measured in terms of m(gluino), is at
least as large, and sometimes larger, than in the mSUGRA framework. In the best
case of the co-NLSP scenario, the reach extends to m(gluino) >~ 3 TeV, assuming
10 fb^-1 of integrated luminosity.

</DOC>
<DOC>
<DOCNO> 152035 </DOCNO>
Democratic Supersymmetry


  We present generalisations of N-extended supersymmetry algebras in four
dimensions, using Lorentz covariance and invariance under permutation of the N
supercharges as selection criteria.

</DOC>
<DOC>
<DOCNO> 152513 </DOCNO>
The geometry of the M5-branes and TQFTs


  The calculation of the partition function for N M5-branes is addressed for
the case in which the worldvolume wraps a manifold $T^2\times M_4$, where $M_4$
is simply connected and Kaehler. This is done in a compactification of M-theory
which induces the Vafa-Witten theory on $M_4$ in the limit of vanishing torus
volume. The results follow from the equivalence of the BPS spectrum counting in
the complementary limit of vanishing $M_4$ volumes and from a classification of
the the moduli space of quantum vacua of the supersymmetric twisted theory in
terms of associated spectral covers. This reduces the problem of the moduli
counting to algebraic equations.

</DOC>
<DOC>
<DOCNO> 7824 </DOCNO>
Orbital Structure and Magnetic Ordering in Layered Manganites: Universal


  Correlation between orbital structure and magnetic ordering in bilayered
manganites is examined. A level separation between the $3d_{3z^2-r^2}$ and
$3d_{x^2-y^2}$ orbitals in a Mn ion is calculated in the ionic model for a
large number of the compounds. It is found that the relative stability of the
orbitals dominates the magnetic transition temperatures as well as the magnetic
structures. A mechanism of the correlation between orbital and magnetism is
investigated based on the theoretical model with the two $e_g$ orbitals under
strong electron correlation.

</DOC>
<DOC>
<DOCNO> 71949 </DOCNO>
Statistical model for pionic partons


  We present a model for the structure of the pion. Based on ideas of a
recently developed statistical model of the nucleon, we assume the pion to be a
gas of partons. The finite-size corrections (FSC) are incorporated through two
parameters. Using the same two FSC parameters for the proton and pion we
reproduce quantitatively the data on $\pi^- N \to \mu^+ \mu^- X$ Drell-Yan
production and valence quark distribution of the pion.

</DOC>
<DOC>
<DOCNO> 151334 </DOCNO>
Causality of Massive Spin 2 Field in External Gravity


  We investigate the structure of equations of motion and lagrangian
constraints in a general theory of massive spin 2 field interacting with
external gravity. We demonstrate how consistency with the flat limit can be
achieved in a number of specific spacetimes. One such example is an arbitrary
static spacetime though equations of motion in this case may lack causal
properties. Another example is provided by external gravity fulfilling vacuum
Einstein equations with arbitrary cosmological constant. In the latter case
there exists one-parameter family of theories describing causal propagation of
the correct number of degrees of freedom for the massive spin 2 field in
arbitrary dimension. For a specific value of the parameter a gauge invariance
with a vector parameter appears, this value is interpreted as massless limit of
the theory. Another specific value of the parameter produces gauge invariance
with a scalar parameter and this cannot be interpreted as a consistent massive
or massless theory.

</DOC>
<DOC>
<DOCNO> 13145 </DOCNO>
Giant negative magnetoresistance in semiconductors doped by multiply


  A giant negative magnetoresistance has been observed in bulk germanium doped
with multiply charged deep impurities. Applying a magnetic field the resistance
may decrease exponentially at any orientation of the field. A drop of the
resistance as much as about 10000% has been measured at 6 T. The effect is
attributed to the spin splitting of impurity ground state with a very large
g-factor in the order of several tens depending on impurity.

</DOC>
<DOC>
<DOCNO> 117095 </DOCNO>
Convergence improvement for coupled cluster calculations


  Convergence problems in coupled-cluster iterations are discussed, and a new
iteration scheme is proposed. Whereas the Jacobi method inverts only the
diagonal part of the large matrix of equation coefficients, we invert a matrix
which also includes a relatively small number of off-diagonal coefficients,
selected according to the excitation amplitudes undergoing the largest change
in the coupled cluster iteration. A test case shows that the new IPM (inversion
of partial matrix) method gives much better convergence than the
straightforward Jacobi-type scheme or such well-known convergence aids as the
reduced linear equations or direct inversion in iterative subspace methods.

</DOC>
<DOC>
<DOCNO> 120996 </DOCNO>
Flat radio-spectrum galaxies and BLLacs: Part I: core properties


  This paper concerns the relationship of BLLacs and flat spectrum weak
emission-line galaxies. We compare the weak emission-line galaxies and the
BLLacs in a sample of 57 flat spectrum objects (Marcha et al. 1996), using
high-frequency radio and non-thermal optical flux densities, spectral indices
and polarization properties. We consider whether objects which are not
`traditional' BLLacs-due to their larger emission line strengths, and larger
CaII spectral breaks-are simply starlight diluted BLLacs. Their broad-band
spectral properties are consistent with this interpretation, but their radio
polarization may indicate more subtle effects. Comparison of the weak
emission-line galaxies and the BLLacs shows that, on average, the former have
steeper spectra between 8 and 43GHz, and are less polarized at 8.4GHz. This is
consistent with many of the weak-lined objects being at larger angles to the
line of sight than the BLLacs. In addition to this population, we indicate a
number of the weak emission-line galaxies which may be `hidden BLLacs':
relativistically boosted objects very close to the line of sight with an
apparently weak AGN.

</DOC>
<DOC>
<DOCNO> 151070 </DOCNO>
On the effective action of local composite fields


  The gauge invariant method for calculation of the effective action of the
local composite fields in QFT is proposed. The effective action of the local
composite fields in QED is studied up to 2-loop level. The graph rules for the
local composite fields are derived. On the basis of these rules the problem of
one-particle irreducibility is discussed.

</DOC>
<DOC>
<DOCNO> 85404 </DOCNO>
Gravitoelectromagnetism


  Gravitoelectromagnetism is briefly reviewed and some recent developments in
this topic are discussed. The stress-energy content of the
gravitoelectromagnetic field is described from different standpoints. In
particular, the gravitational Poynting flux is analyzed and it is shown that
there exists a steady flow of gravitational energy circulating around a
rotating mass.

</DOC>
<DOC>
<DOCNO> 123211 </DOCNO>
PSR J1740-3052 - a pulsar with a massive companion


  We report on the discovery of a binary pulsar, PSR J1740-3052, during the
Parkes multibeam survey. Timing observations of the 570-ms pulsar at Jodrell
Bank and Parkes show that it is young, with a characteristic age of 350 kyr,
and is in a 231-day, highly eccentric orbit with a companion whose mass exceeds
11 M_sun. An accurate position for the pulsar was obtained using the Australia
Telescope Compact Array. Near-infrared 2.2-um observations make with the
telescopes at the Siding Spring observatory reveal a late-type star coincident
with the pulsar position. However, we do not believe that this star is the
pulsar's companion, because a typical star of this spectral type and required
mass would extend beyond the pulsar's orbit. Furthermore, the measured advance
of periastron of the pulsar suggests a more compact companion, for example, a
main-sequence star with radius only a few times that of the sun. Such a
companion is also more consistent with the small dispersion measure variations
seen near periastron. Although we cannot conclusively rule out a black-hole
companion, we believe the companion is probably an early B star, making the
system similar to the binary PSR J0045-7319.

</DOC>
<DOC>
<DOCNO> 169637 </DOCNO>
Note on Separability of the Werner states in arbitrary dimensions


  Great progress has been made recently in establishing conditions for
separability of a particular class of Werner densities on the tensor product
space of $n$ $d$--level systems (qudits). In this brief note we complete the
process of establishing necessary and sufficient conditions for separability of
these Werner densities by proving the sufficient condition for general n and d.

</DOC>
<DOC>
<DOCNO> 12318 </DOCNO>
Semiclassical calculation of the nucleation rate for first order phase


  In many systems in condensed matter physics and quantum field theory, first
order phase transitions are initiated by the nucleation of bubbles of the
stable phase. Traditionally, this process is described by the semiclassical
nucleation theory developed by Langer and, in the context of quantum field
theory, by Callan and Coleman. They have shown that the nucleation rate
$\Gamma$ can be written in the form of the Arrhenius law:
$\Gamma=\mathcal{A}e^{-\mathcal{H}_{c}}$. Here $\mathcal{H}_{c}$ is the energy
of the critical bubble, and the prefactor $\mathcal{A}$ can be expressed in
terms of the determinant of the operator of fluctuations near the critical
bubble state. It is not possible to find explicit expressions for the constants
$\mathcal{A}$ and $\mathcal{H}_{c}$ in the general case of a finite difference
$\eta$ between the energies of the stable and metastable vacua. For small
$\eta$, the constant $\mathcal{A}$ can be determined within the leading
approximation in $\eta$, which is an extension of the ``thin wall
approximation''. We have calculated the leading approximation of the prefactor
for the case of a model with a real-valued order parameter field in two
dimensions.

</DOC>
<DOC>
<DOCNO> 151877 </DOCNO>
From Reflection Amplitudes to One-point Functions in Non-simply Laced


  The reflection amplitudes in non-affine Toda theories which possess extended
conformal symmetry are calculated. Considering affine Toda theories as
perturbed non-affine Toda theories and using reflection relations which relate
different fields with the same conformal dimension, we deduce the vacuum
expectation values of local fields for all dual pairs of non-simply laced
affine Toda field theories. As an application, we calculate the leading term in
the short and long distance predictions of the two-point correlation functions
in the massive phase of two coupled minimal models. The central charge of the
unperturbed models ranges from $c=1$ to $c=2$, where the perturbed models
correspond to two magnetically coupled Ising models and Heisenberg spin
ladders, respectively.

</DOC>
<DOC>
<DOCNO> 13280 </DOCNO>
Exchange Field Induced Magnetoresistance in Colossal Magnetoresistance


  The effect of an exchange field on electrical transport in thin films of
metallic ferromagnetic manganites has been investigated. The exchange field was
induced both by direct exchange coupling in a ferromagnet/antiferromagnet
multilayer and by indirect exchange interaction in a ferromagnet/paramagnet
superlattice. The electrical resistance of the manganite layers was found to be
determined by the absolute value of the vector sum of the effective exchange
field and the external magnetic field.

</DOC>
<DOC>
<DOCNO> 84975 </DOCNO>
How to Extract Energy Directly from a Gravitational Field


  Gravity is related to gravitational mass of the bodies. According to the weak
form of Einstein's General Relativity equivalence principle, the gravitational
and inertial masses are equivalent. However recent calculations (gr-qc/9910036)
have revealed that they are correlated by an adimensional factor, which depends
on the incident radiation upon the particle. It was shown that there is a
direct correlation between the radiation absorbed by the particle and its
gravitational mass, independently of the inertial mass. This finding has
fundamental consequences to Unified Field Theory and Quantum Cosmology. It was
also shown that only in the absence of electromagnetic radiation this factor
becomes equal to one and that, in specific electromagnetic conditions, it can
be reduced, nullified or made negative. This means that there is the
possibility of control of the gravitational mass by means of the incident
radiation. This unexpected theoretical result was recently confirmed by an
experiment (gr-qc/0005107). Consequently there is a strong evidence that the
gravitational forces can be reduced, nullified and inverted by means of
electromagnetic radiation. This means that, in practice we can produce
gravitational binaries, and in this way to extract energy from a gravitational
field. Here we describe a process by which energy can be extracted directly
from any site of a gravitational field.

</DOC>
<DOC>
<DOCNO> 101550 </DOCNO>
Perturbation of Domain: Ordinary Differential Equations


  We work with the Friedrichs extension of a one dimensional Schrodinger whose
potential has a certain type of regular singularity near one end point. We
study the effect on the eigenvalues of shrinking the region slightly near the
end point. In particular we calculate the rate at which the eigenvalues of the
smaller region converge to the eigenvalues of the larger region as the region
expands. A result of this type was needed by that author in another paper
concerned with a domain perturbation problem on Riemannian manifolds. The
problem here, however, is stated purely in terms of ordinary differential
equations.

</DOC>
<DOC>
<DOCNO> 72031 </DOCNO>
Variations on Supersymmetry Breaking and Neutrino Spectra


  The problem of generating light neutrinos within supersymmetric models is
discussed. It is shown that the hierarchy of scales induced by supersymmetry
breaking can give rise to suppression factors of the correct order of magnitude
to produce experimentally allowed neutrino spectra.

</DOC>
<DOC>
<DOCNO> 71352 </DOCNO>
Simulation accuracy of long range muon propagation in medium: analysis


  Knowledge of atmospheric muon flux intensity at large depths is extremely
important for neutrino telescopes located deep under ground, water or ice. One
of the methods to transform muon sea-level spectrum into depth one is to apply
Monte Carlo technique which directly takes into account stochastical nature of
energy loss. In order to decrease computation time down to acceptable level one
has to use simplifications resulting in systematic errors which in some cases
may distort result essentially. Here in this paper we present our analysis for
dependence of computed depth muon flux upon the most important parameters of
muon transport Monte Carlo algorithm which was done with the MUM (MUons+Medium)
code. Contribution of different simplifications to the resulting error is
considered, ranked and compared with uncertainties which come from
parametrization accuracy both for sea-level muon spectrum and for muon cross
sections.

</DOC>
<DOC>
<DOCNO> 119501 </DOCNO>
Spectral Energy Distributions of Active Galactic Nuclei from an


  To explain the broad-band spectral energy distributions (SED) of Seyfert
nuclei and QSOs, we study the emission spectrum emerging from a vertical
disk-corona structure composed of a two-temperature plasma by solving
hydrostatic equilibrium and radiative transfer self-consistently. Our model can
nicely reproduce the soft X-ray excess with alpha (L_frequency proportional to
the frequency to the power of -alpha) of about 1.5 and the hard tail extending
to about 50 keV with alpha about 0.5. The different spectral slopes (alpha
about 1.5 below 2 keV and about 0.5 above) are the results of different
emission mechanisms: unsaturated Comptonization in the former and a combination
of Comptonization, bremsstrahlung, and reflection of the coronal radiation at
the disk-corona boundary in the latter.

</DOC>
<DOC>
<DOCNO> 150908 </DOCNO>
Matrix Theory Interpretation of DLCQ String Worldsheets


  We study the null compactification of type-IIA-string perturbation theory at
finite temperature. We prove a theorem about Riemann surfaces establishing that
the moduli spaces of infinite-momentum-frame superstring worldsheets are
identical to those of branched-cover instantons in the matrix-string model
conjectured to describe M-theory. This means that the identification of string
degrees of freedom in the matrix model proposed by Dijkgraaf, Verlinde and
Verlinde is correct and that its natural generalization produces the moduli
space of Riemann surfaces at all orders in the genus expansion.

</DOC>
<DOC>
<DOCNO> 70475 </DOCNO>
DVCS amplitude with kinematical twist-3 terms


  We compute the amplitude of deeply virtual Compton scattering (DVCS) using
the calculus of QCD string operators in coordinate representation. To restore
the electromagnetic gauge invariance
 (transversality) of the twist-2 amplitude we include the operators of twist-3
which appear as total derivatives of twist-2 operators. Our results are
equivalent to a Wandzura-Wilczek approximation for twist-3 skewed parton
distributions. We find that this approximation gives a finite result for the
amplitude of a longitudinally polarized virtual photon, while the amplitude for
transverse polarization is divergent, i.e., factorization breaks down in this
term. However, the divergent part has zero projection onto the polarization
vector of the final real photon.

</DOC>
<DOC>
<DOCNO> 11779 </DOCNO>
Branching annihilating random walk on random regular graphs


  The branching annihilating random walk is studied on a random graph whose
sites have uniform number of neighbors (z). The Monte Carlo simulations in
agreement with the generalized mean-field analysis indicate that the
concentration decreses linearly with the branching rate for $z \ge 4$ while the
coefficient of the linear term becomes zero if $z=3$. These features are
described by a modified mieb-field theory taking explicitly into consideration
the probability of mutual annihilation of the parent and its offspring
particles using the returning features of a single walker on the same graph.

</DOC>
<DOC>
<DOCNO> 69359 </DOCNO>
Subleading Sudakov Logarithms in Electroweak Processes


  Recent results for the asymptotic behavior of fermion scattering amplitudes
in the Sudakov limit are presented including next-to-leading logarithmic
corrections. These are used for the analysis of the dominant electroweak
corrections to the fermion-antifermion pair production in $e^+e^-$ annihilation
at high energy.

</DOC>
<DOC>
<DOCNO> 122269 </DOCNO>
The Evolution of Ly-alpha Absorbing Galaxies


  The evolution of Ly-alpha absorber counts is simulated for a model population
of absorbing galaxies. The distribution of gas relative to galaxies could
evolve between moderate and low redshifts, but constraints are needed on the
strength and evolution of the ionizing UV background.

</DOC>
<DOC>
<DOCNO> 10736 </DOCNO>
Influence of vortex-vortex interaction on critical currents across


  Low-angle grain boundaries with misorientation angles theta < 5 degrees in
optimally doped thin films of YBCO are investigated by magnetooptical imaging.
By using a numerical inversion scheme of Biot-Savart's law the critical current
density across the grain boundary can be determined with a spatial resolution
of about 5 micrometers. Detailed investigation of the spatially resolved flux
density and current density data shows that the current density across the
boundary varies with varying local flux density. Combining the corresponding
flux and current pattern it is found that there exists a universal dependency
of the grain boundary current on the local flux density. A change in the local
flux density means a variation in the flux line-flux line distance. With this
knowledge a model is developped that explains the flux-current relation by
means of magnetic vortex-vortex interaction.

</DOC>
<DOC>
<DOCNO> 101140 </DOCNO>
Vanishing cycles and mutation


  This is the writeup of a talk given at the European Congress of Mathematics,
Barcelona. It considers Picard-Lefschetz theory from the Floer cohomology
viewpoint.

</DOC>
<DOC>
<DOCNO> 69888 </DOCNO>
New constraints on multi-field inflation with nonminimal coupling


  We study the dynamics and perturbations during inflation and reheating in a
multi-field model where a second scalar field $\chi$ is nonminimally coupled to
the scalar curvature $(\frac12 \xi R\chi^2$). When $\xi$ is positive, the usual
inflationary prediction for large-scale anisotropies is hardly altered while
the $\chi$ fluctuation in sub-Hubble modes can be amplified during preheating
for large $\xi$. For negative values of $\xi$, however, long-wave modes of the
$\chi$ fluctuation exhibit exponential increase during inflation, leading to
the strong enhancement of super-Hubble metric perturbations even when $|\xi|$
is less than unity. This is because the effective $\chi$ mass becomes negative
during inflation. We constrain the strength of $\xi$ and the initial $\chi$ by
the amplitude of produced density perturbations. One way to avoid nonadiabatic
growth of super-Hubble curvature perturbations is to stabilize the $\chi$ mass
through a coupling to the inflaton. Preheating may thus be necessary in these
models to protect the stability of the inflationary phase.

</DOC>
<DOC>
<DOCNO> 170657 </DOCNO>
Quantum Computation with Harmonic Oscillators


  By encoding a qudit in a harmonic oscillator and investigating the infinite
limit, we give an entirely new realization of continuous-variable quantum
computation. The generalized Pauli group is generated by number and phase
operators for harmonic oscillators. We describe a physical realization in terms
of modes in a microwave cavity, coupled via a standard Kerr nonlinearity.

</DOC>
<DOC>
<DOCNO> 120400 </DOCNO>
Numerical Simulations of Weak Lensing Measurements


  (Abridged) Weak gravitational lensing induces distortions on the images of
background galaxies, and thus provides a direct measure of mass fluctuations in
the universe. Since the distortions induced by lensing on the images of
background galaxies are only of a few percent, a reliable measurement demands
very accurate galaxy shape estimation and a careful treatment of systematic
effects. Here, we present a study of a shear measurement method using detailed
simulations of artificial images. The images are produced using realisations of
a galaxy ensemble drawn from the HST Groth strip. We consider realistic
observational effects including atmospheric seeing, PSF anisotropy and
pixelisation, incorporated in a manner to reproduce actual observations with
the William Herschel Telescope. By applying an artificial shear to the
simulated images, we test the shear measurement method proposed by Kaiser,
Squires & Broadhurst (1995, KSB). Overall, we find the KSB method to be
reliable with several provisos. To guide future weak lensing surveys, we study
how seeing size, exposure time and pixelisation affect the sensitivity to
shear. In addition, we study the impact of overlapping isophotes of neighboring
galaxies, and find that this effect can produce spurious lensing signals on
small scales. We discuss the prospects of using the KSB method for future, more
sensitive, surveys. Numerical simulations of this kind are a required component
of present and future analyses of weak lensing surveys.

</DOC>
<DOC>
<DOCNO> 13388 </DOCNO>
Thermodynamics of d-wave superconductors in a magnetic field


  We investigate the thermodynamic properties of a two-dimensional d-wave
superconductor in the vortex state using a semiclassical approach, and argue
that such an approach is valid for the analysis of the experimental data on
high-temperature superconductors. We develop a formalism where the spatial
average of a physical quantity is written as an integral over the probability
density of the Doppler shift, and evaluate this probability density for several
model cases. The approach is then used to analyse the behavior of the specific
heat and the NMR spin-lattice relaxation rate in a magnetic field. We compare
our results with the experimental measurements, and explain the origin of the
discrepancy between the results from different groups. We also address the
observability of the recently predicted fourfold oscillations of the specific
heat for the magnetic field parallel to the copper oxide planes. We consider
both the orbital and the Zeeman effects, and conclude that at experimentally
relevant temperatures Zeeman splitting does not appreciably reduce the
anisotropy, although it does change the field dependence of the anisotropic
specific heat. We predict a scaling law for the non-exponentially decaying NMR
magnetization, and discuss different approaches to the effective relaxation
rate.

</DOC>
<DOC>
<DOCNO> 40471 </DOCNO>
Connection between Distribution and Fragmentation Functions


  We show that the quark fragmentation function $D(z)$ and the quark
distribution function $q(x)$ are connected in the $z \to 1$ limit by the
approximate relation $D(z)/z \simeq q(2-1/z)$, where both quantities are in
their physical regions. Predictions for proton production in inelastic $e^+
e^-$ annihilation, based on the new relation and standard parametrizations of
quark distribution functions, are found to be compatible with the data.

</DOC>
<DOC>
<DOCNO> 102211 </DOCNO>
Construction of boundary invariants and the logarithmic singularity of


  This paper studies Fefferman's program \cite{F3} of expressing the
singularity of the Bergman kernel, for smoothly bounded strictly pseudoconvex
domains $\Omega\subset\C^n$, in terms of local biholomorphic invariants of the
boundary. By \cite{F1}, the Bergman kernel on the diagonal $K(z,\c{z})$ is
written in the form $$
  K=\phi r^{-n-1}+\psi \log r \qtext{with}
  \phi,\psi\in C^\infty(\c\Omega), $$ where $r$ is a (smooth) defining function
of $\Omega$. Recently, Bailey, Eastwood and Graham \cite{BEG}, building on
Fefferman's earlier work \cite{F3}, obtained a full invariant expression of the
strong singularity $\phi r^{-n-1}$. The purpose of this paper is to give a full
invariant expression of the weak singularity $\psi\log r$.

</DOC>
<DOC>
<DOCNO> 71180 </DOCNO>
Lambda and Lambda-bar polarization as a measurement of distribution and


  A combined analysis of the polarization vector of the Lambda baryons produced
in DIS processes may give a relevant insight of the hadronization process which
governs the transition from partons to physical hadrons and precise indications
on the mechanisms of $spin$ transfer from partons to hadrons. We give here a
short review of some interesting results.

</DOC>
<DOC>
<DOCNO> 68616 </DOCNO>
Effect of flavor mixing on the time delay of massive supernova neutrinos


  The neutrinos and antineutrinos of all the three flavors released from a
galactic supernova will be detected in the water Cerenkov detectors. We show
that even though the neutral current interaction is flavor blind, and hence
neutrino flavor mixing cannot alter the total neutral current signal in the
detector, it can have a non-trivial impact on the delay of massive neutrinos
and alters the neutral current event rate as a function of time. We have
suggested various variables of the neutral and charged current events that can
be used to study this effect. In particular the ratio of charged to neutral
current events can be used at early times while the ratio of the energy moments
for the charged to the neutral current events can form useful diagnostic tools
even at late times to study neutrino mass and mixing.

</DOC>
<DOC>
<DOCNO> 11148 </DOCNO>
Scaling near the upper critical dimensionality in the localization


  The phenomenon of upper critical dimensionality d_c2 has been studied from
the viewpoint of the scaling concepts. The Thouless number g(L) is not the only
essential variable in scale transformations, because there is the second
parameter connected with the off-diagonal disorder. The investigation of the
resulting two-parameter scaling has revealed two scenarios, and the switching
from one to another scenario determines the upper critical dimensionality. The
first scenario corresponds to the conventional one-parameter scaling and is
characterized by the parameter g(L) invariant under scale transformations when
the system is at the critical point. In the second scenario, the Thouless
number g(L) grows at the critical point as L^{d-d_c2}. This leads to violation
of the Wegner relation s=\nu(d-2) between the critical exponents for
conductivity (s) and for localization radius (\nu), which takes the form
s=\nu(d_c2-2). The resulting formulas for g(L) are in agreement with the
symmetry theory suggested previously [JETP 81, 925 (1995)]. A more rigorous
version of Mott's argument concerning localization due topological disorder has
been proposed.

</DOC>
<DOC>
<DOCNO> 70619 </DOCNO>
On a Probable Contribution of the Einstein-Podolsky-Rosen Effect to


  Evading formation of the domain walls in cosmological phase transitions is
one of key problems to be solved for explanation of the observed large-scale
homogeneity of the Universe. The previous attempts to get around this obstacle
led to imposing severe observational constraints on the parameters of the
fields involved. Aim of the present report is to show that yet another way to
overcome the above problem is accounting for Einstein-Podolsky-Rosen (EPR)
effect. Namely, if the scalar (Higgs) field was presented by a single coherent
quantum state at the initial instant of time, then its reduction during a phase
transition at some later instant should be correlated even at distances
exceeding the local cosmological horizon. Consideration of a simplest
one-dimensional cosmological model with Z_2 Higgs field demonstrates that EPR
correlations can substantially reduce the probability of spontaneous creation
of the domain walls, and such effect seems to be even more promising in the
cases of two- and three-dimensional geometry.

</DOC>
<DOC>
<DOCNO> 151984 </DOCNO>
Towards Covariant Matrix Theory


  We review an approach towards a covariant formulation of Matrix theory based
on a discretization of the 11d membrane. Higher dimensional algebraic
structures, such as the quantum triple Nambu bracket, naturally appear in this
approach. We also discuss a novel geometric understanding of the space-time
uncertainty relation which points towards a more geometric formulation of
Matrix theory.

</DOC>
<DOC>
<DOCNO> 13325 </DOCNO>
Observation of the antiferroquadrupolar order in DyB2C2 by resonant


  We have investigated the antiferroquadrupolar(AFQ) order in DyB$_2$C$_2$ by
resonant x-ray scattering. X-rays with energies near the $L_3$ absorption edge
of Dy were employed. Superlattice peaks that correspond to three kinds of
propagation vectors of (1 0 0), (1 0 1/2) and (0 0 1/2) were investigated in
detail with polarization analyses. The experimental results are analyzed using
a formalism on resonant x-ray scattering and a model of the AFQ order. The
magnetic and quadrupolar scatterings are explained by the model satisfactorily.
A detailed investigation on the critical behavior of the AFQ ordering is also
reported. The critical exponent $\beta$ is deduced to be 0.35, not far from the
three-dimensional Heisenberg system. We have also succeeded in detecting the
diffuse scattering above $T_{Q}$.

</DOC>
<DOC>
<DOCNO> 8812 </DOCNO>
Finite Temperature Dynamic Structure Function of the Free Fermi Gas


  A detailed discussion of the coherent and incoherent dynamic structure
function of the free Fermi gas at finite temperature is presented. Their
behavior and evolution with the momentum transfer and the temperature is
analyzed, while particular attention is paid to the way in which their relative
contribution changes with respect to the $\tilde{T}=0$ case. The influence of
thermal effects on the lowest order sum rules of the coherent and incoherent
responses is also discussed. Finally, the scaling properties of the responses
at high momentum transfer as a function of the temperature are also analyzed.

</DOC>
<DOC>
<DOCNO> 83095 </DOCNO>
Making news understandable to computers


  Computers and devices are largely unaware of events taking place in the
world. This could be changed if news were made available in a
computer-understandable form. In this paper we present XML documents called
NewsForms that represent the key points of 17 types of news events. We discuss
the benefits of computer-understandable news and present the NewsExtract
program for converting text news stories into NewsForms.

</DOC>
<DOC>
<DOCNO> 70713 </DOCNO>
Inclusive Quark Production in $e^{+}e^{-}$-Annihilation - A Path


  The single-particle inclusive differential cross-section for a reaction
$a+b\to c+X$ is written as imaginary part of a correlation function in a
forward scattering amplitude for $a+b\to a+b$ in a modified effective theory.
In this modified theory the interaction Hamiltonian $\tilde H_I$ equals $H_I$
of the original theory up to a certain time. Then there is a sign change and
$\tilde H_I$ becomes nonlocal. This is worked out in detail for scalar field
models and for QED plus the abelian gluon model. A suitable path integral for
direct calculations of inclusive cross sections is presented.

</DOC>
<DOC>
<DOCNO> 13060 </DOCNO>
Calculation of an effective three-ionic interactions potential in


  The pair- and three-proton interaction potentials for metal-phase hydrogen
are calculated. Irreducible three-proton interactions are shown to be essential
in the development of the metal hydrogen structure. Possible manifestations of
the three-ion interactions in the structure of quickly quenched metallic
systems are discussed. Existence of amorphous metals is related to
manifestations of the three-ion interactions in non-equilibrium conditions when
amorphisation front travels through a liquid metal.

</DOC>
<DOC>
<DOCNO> 117636 </DOCNO>
Observing the effects of strong gravity with future X-ray missions


  Spectroscopy of the broad iron iron with ASCA and BeppoSAX has up opened the
innermost regions of accreting black hole systems to detailed study. In this
contribution, I discuss how observations with future X-ray missions will extend
these studies and all us to observationally address issues which are currently
only in the realm of the theorists. In particular, high-throughput spectroscopy
with XMM and, eventually, Constellation-X will allow the full diagnostic power
of iron line variability to be realized. Instabilities of the inner accretion
flow, the geometry of the variable X-ray source, and the black hole mass and
spin will all be open to study. Eventually, X-ray interferometry will allow
direct imaging of the black hole region in nearby active galaxies, thereby
providing the ultimate probe of black hole astrophysics.

</DOC>
<DOC>
<DOCNO> 72014 </DOCNO>
Phenomenology of the Neutrino-Mass-Giving Higgs Triplet and the


  Small realistic Majorana neutrino masses can be generated via a Higgs triplet
$(\xi^{++}, \xi^+, \xi^0)$ without having energy scales larger than $M_*={\cal
O}(1)$ TeV in the theory. The large effective mass scale $\Lambda$ in the
well-known seesaw neutrino-mass operator $\Lambda^{-1} (LL\Phi\Phi)$ is
naturally obtained with $\Lambda\sim M_*^2/\mu,$ where $\mu$ is a {\it small}
scale of lepton-number violation. In theories with large extra dimensions, the
smallness of $\mu$ is naturally obtained by the mechanism of ``shining'' if the
number of extra dimensions $n\ge 3.$ We study here the Higgs phenomenology of
this model, where the spontaneous violation of lepton number is treated as an
external source from extra dimensions. The observable decays $\xi^{++} \to
l_i^+l_j^+$ will determine directly the magnitudes of the $\{ij\}$ elements of
the neutrino mass matrix. The decays $\xi^+ \to W^+ J^0$ and $\xi^0 \to Z J^0$,
where $J^0$ is the massless Goldstone boson (Majoron), are also possible, but
of special importance is the decay $\xi^0 \to J^0 J^0$ which provides stringent
constraints on the allowed parameter space of this model. Based on the current
neutrino data, we also predict observable rates of $\mu-e$ conversion in
nuclei.

</DOC>
<DOC>
<DOCNO> 68853 </DOCNO>
Relating different approaches to nonlinear QCD evolution at finite gluon


  We analyze the relation between evolution equations at low x that have been
derived in different approaches in the last several years. We show that the
equation derived by Balitsky and Kovchegov is obtained from the
Jalilian-Marian-Kovner-Leonidov-Weigert (JKLW) equation in the limit of small
induced charge density. We argue that the higher nonlinearities resummed by the
JKLW equation correspond, in physical terms, to the breakdown of the eikonal
approximation when the gluon fields in the target are large.

</DOC>
<DOC>
<DOCNO> 83373 </DOCNO>
A usage based analysis of CoRR


  Based on an empirical analysis of author usage of CoRR, and of its
predecessor in the Los Alamos eprint archives, it is shown that CoRR has not
yet been able to match the early growth of the Los Alamos physics archives.
Some of the reasons are implicit in Halpern's paper, and we explore them
further here. In particular we refer to the need to promote CoRR more
effectively for its intended community - computer scientists in universities,
industrial research labs and in government. We take up some points of detail on
this new world of open archiving concerning central versus distributed
self-archiving, publication, the restructuring of the journal publishers'
niche, peer review and copyright.

</DOC>
<DOC>
<DOCNO> 178761 </DOCNO>
Thermal and Nonthermal Pion Enhancements with Chiral Symmetry


  The pion production by sigma decay and its relation with chiral symmetry
restoration in a hot and dense matter are investigated in the framework of the
Nambu-Jona-Lasinio model. The decay rate for the process sigma -> 2pion to the
lowest order in a 1/N_c expansion is calculated as a function of temperature T
and chemical potential mu. The thermal and nonthermal enhancements of pions
generated by the decay before and after the freeze-out present only in the
crossover region of the chiral symmetry transition. The strongest nonthermal
enhancement is located in the vicinity of the endpoint of the first-order
transition.

</DOC>
<DOC>
<DOCNO> 9186 </DOCNO>
Formation of a New Class of Random Fractals in Fragmentation with Mass


  We consider the fragmentation process with mass loss and discuss self-similar
properties of the arising structure both in time and space focusing on
dimensional analysis. This exhibits a spectrum of mass exponents $\theta$,
whose exact numerical values are given for which $x^{-\theta}$ or $t^{\theta
z}$ has the dimension of particle size distribution function c(x,t) where z
is the kinetic exponent. We also give explicit scaling solution for special
case. Finally, we identify a new class of fractals ranging from random to
non-random and show that the fractal dimension increases with increasing order
and a transition to strictly self-similar pattern occurs when randomness is
completely seized.

</DOC>
<DOC>
<DOCNO> 7686 </DOCNO>
Overlapping of the characteristic regions in the decay on heterogeneous


  The situation of the decay of the metastable phase on the several types of
heterogeneous centers is described analytically. The total number of
heterogeneous centers is supposed to be equal for different types. This
description decomposes the general situation into some characterisrtic cases.
Every case can be described by some special method. The problem is to show that
these characteristic cases cover all possible variants of the composition of
the condensation system. This is done is this manuscript. In the first part we
consider the general facts which allow to establish this overlapping in
principle. In the second part we consider some real model systems and show this
overlapping directly by explicit calculations. In the third part we consider
the process of nucleation on ions and give the generalization for the centers
with a rather arbitrary nature.

</DOC>
<DOC>
<DOCNO> 102821 </DOCNO>
Some results related to the Logvinenko-Sereda theorem


  We prove several results related to the theorem of Logvinenko and Sereda on
determining sets for functions with Fourier transforms supported in an
interval. We obtain a polynomial instead of exponential bound in this theorem,
and we extend it to the case of functions with Fourier transforms supported in
the union of a bounded number of intervals. The same results hold in all
dimensions.

</DOC>
<DOC>
<DOCNO> 9001 </DOCNO>
Multifractality and critical fluctuations at the Anderson transition


  Critical fluctuations of wave functions and energy levels at the Anderson
transition are studied for the family of the critical power-law random banded
matrix ensembles. It is shown that the distribution functions of the inverse
participation ratios (IPR) $P_q$ are scale-invariant at the critical point,
with a power-law asymptotic tail. The IPR distribution, the multifractal
spectrum and the level statistics are calculated analytically in the limits of
weak and strong couplings, as well as numerically in the full range of
couplings.

</DOC>
<DOC>
<DOCNO> 11840 </DOCNO>
A Model for Addition Spectra in Quantum Dots


  A simple model for addition spectra in quantum dots is proposed and studied.
It is an extension of the standard charging model which assumes that the charge
spreads uniformely over the entire dot. The proposed model attempts to account
for a nonuniform distribution of the charge, by introducing an extra parameter
U. When U increases, the distribution of the conductance peak spacings changes
from the Wigner-Dyson shape towards a broader, more symmetric distribution.

</DOC>
<DOC>
<DOCNO> 40241 </DOCNO>
Reanalysis of CP Violation in K_L -> pi^+ pi^- gamma


  We present a reanalysis of direct CP violation in the decay K_L -> pi^+ pi^-
gamma. We point out an existing discrepancy between the theoretical and
experimental definitions of epsilon'_{+-gamma}. Adopting the experimental
definition of epsilon'_{+-gamma}, we estimate that epsilon'_{+-gamma}/epsilon
could be as large as a few times 10^{-4} both within the standard model and
beyond. We discuss these estimates in detail and we also show how a judicious
choice of E_gamma cuts can increase the sensitivity of the observable
epsilon'_{+-\gamma} to the underlying CP violation.

</DOC>
<DOC>
<DOCNO> 11719 </DOCNO>
Hole dynamics in noble metals


  We present a detailed analysis of hole dynamics in noble metals (Cu and Au),
by means of first-principles many-body calculations. While holes in a
free-electron gas are known to live shorter than electrons with the same
excitation energy, our results indicate that d-holes in noble metals exhibit
longer inelastic lifetimes than excited sp-electrons, in agreement with
experiment. The density of states available for d-hole decay is larger than
that for the decay of excited electrons; however, the small overlap between d-
and sp-states below the Fermi level increases the d-hole lifetime. The impact
of d-hole dynamics on electron-hole correlation effects, which are of relevance
in the analysis of time-resolved two-photon photoemission experiments, is also
addressed.

</DOC>
<DOC>
<DOCNO> 68524 </DOCNO>
Baryon Number Asymmetry Induced by Coherent Motions of a Cosmological


  A cosmological pseudoscalar field coupled to hypercharge topological number
density can exponentially amplify hyperelectric and hypermagnetic fields in the
symmetric phase of the electroweak plasma while coherently rolling or
oscillating, leading to the formation of a condensate of topological number
density. The topological number can be converted, under certain conditions,
into baryon number in sufficient amount to explain the observed baryon
asymmetry of the universe. We focus on a singlet elementary hypercharge axion
(HCA) whose only coupling to standard model fields is to hypercharge
topological number density. This model has two parameters: the mass $m$ and
decay constant $M$ of the HCA. We describe this new mechanism for baryogenesis
and outline the region of the parameter space in which the mechanism is
efficient. We show that present colliders can already put interesting
constraints on both parameters, and that future colliders will improve the
detection capabilities very significatively.

</DOC>
<DOC>
<DOCNO> 174441 </DOCNO>
Gep/Gmp for bound protons: first results for 16O with the recoil


  The first (e,e'p) polarization transfer measurements on a nucleus heavier
than deuterium have been carried out at Jefferson Laboratory. Transverse and
longitudinal components of the polarization of protons ejected in the reaction
16O(e,e'p) were measured in quasielastic perpendicular kinematics at a Q^2 of
0.8 (GeV/c)^2. The data are in good agreement with state of the art
calculations, but do not exclude possible changes in the ratio of the electric
to magnetic form factors of the nucleon in the nuclear medium at the level of
recent theoretical predictions.

</DOC>
<DOC>
<DOCNO> 71197 </DOCNO>
The quantum effects on neutrino mass and lepton flavor mixing (MNS)


  My talk is concentrating on the quantum effects on neutrino mass and lepton
flavor mixing matrices in the framework of the minimal supersymmetric standard
model with the effective dimension-five operator which gives the Majorana
masses of neutrinos.

</DOC>
<DOC>
<DOCNO> 117644 </DOCNO>
Where are the type 2 AGNs?


  Most of the energy of the X-ray background is contributed by sources with a
hard X-ray spectrum, harder than the spectrum observed in nearby type 1 AGNs.
The hard background contributors are conventionally identified with type 2
AGNs, obscured by circumnuclear matter both in the optical and in the soft X
rays. However, preliminary results of identification programs seem to find
systematically few type 2 AGNs in samples selected with obscuration insensitive
criteria. We discuss this issue, and assess the various scenarios which are
being proposed to solve the discrepancy.

</DOC>
<DOC>
<DOCNO> 123088 </DOCNO>
Evidence for an inflationary phase transition from the LSS and CMB


  In the light of the recent Boomerang and Maxima observations of the CMB which
show an anomalously low second acoustic peak, we reexamine the prediction by
Adams et al (1997) that this would be the consequence of a 'step' in the
primordial spectrum induced by a spontaneous symmetry breaking phase transition
during primordial inflation. We demonstrate that a deviation from
scale-invariance around $k\sim0.1h$~Mpc$^{-1}$ can simultaneously explain both
the feature identified earlier in the APM galaxy power spectrum as well the
recent CMB anisotropy data, with a baryon density consistent with the BBN
value. Such a break also allows a good fit to the data on cluster abundances
even for a critical density matter-dominated universe with zero cosmological
constant.

</DOC>
<DOC>
<DOCNO> 84608 </DOCNO>
Boundary conditions for the spinor field in Rindler spacetime and the


  We analyse the quantization procedure of the spinor field in the Rindler
spacetime, showing the boundary conditions that should be imposed to the field,
in order to have a well posed theory. Because of these boundary conditions we
argue that this construction and the usual one in Minkowski spacetime are
qualitatively different and can not be compared and consequently the
conventional interpretation of the Unruh effect, that is the thermal nature of
the Minkowski vacuum state from the point of view of an accelerated observer,
is questionable. We also analyse in detail the Unruh quantization scheme and we
show that it is not valid in the whole Minkowski space but only in the double
Rindler wedge, and it cannot be used as a basis for a quantum theoretical proof
of the Unruh effect.

</DOC>
<DOC>
<DOCNO> 101894 </DOCNO>
Two uniqueness results on the Unruh effect and on PCT-symmetry


  The Unruh effect and a closely related form of PCT-symmetry have been proved
in general for finite-component Wightman fields by Bisognano and Wichmann.
While this result incorporates most of the fields occurring in four-dimensional
high-energy physics, there still are field theories of interest that are not
covered (e.g., low-dimensional anyon fields and infinite-component fields).
  From the spectrum condition, Borchers has derived a couple of commutation
relations which 'almost, but only almost' imply the Unruh effect and
PCT-symmetry. We show that this result does imply the Unruh effect and
PCT-symmetry provided that the operators involved in Borchers' commutation
relations act geometrically on a local net of observables.

</DOC>
<DOC>
<DOCNO> 101198 </DOCNO>
Unbraiding the braided tensor product


  We show that the braided tensor product algebra $A_1\underline{\otimes}A_2$
of two module algebras $A_1, A_2$ of a quasitriangular Hopf algebra $H$ is
equal to the ordinary tensor product algebra of $A_1$ with a subalgebra of
$A_1\underline{\otimes}A_2$ isomorphic to $A_2$, provided there exists a
realization of $H$ within $A_1$. In other words, under this assumption we
construct a transformation of generators which `decouples' $A_1, A_2$ (i.e.
makes them commuting). We apply the theorem to the braided tensor product
algebras of two or more quantum group covariant quantum spaces, deformed
Heisenberg algebras and q-deformed fuzzy spheres.

</DOC>
<DOC>
<DOCNO> 69807 </DOCNO>
Nonleptonic charmless B decays: factorization vs perturbative QCD


  We compare the factorization approach, the perturbative QCD approach and the
Beneke-Buchalla-Neubert-Sachrajda approach to nonleptonic charmless $B$ meson
decays. We discuss their treatments of factorizable, nonfactorizable, and
annihilation contributions, infrared-cutoff and scale dependences, and strong
phases. It is proposed that measurement of CP asymmetries in two-body $B$ meson
decays provides an appropriate test of the these approaches.

</DOC>
<DOC>
<DOCNO> 101627 </DOCNO>
The Einstein-Podolsky-Rosen state maximally violates Bell's inequalities


  In their well-known argument against the completeness of quantum theory,
Einstein, Podolsky, and Rosen (EPR) made use of a state that strictly
correlates the positions and momenta of two particles. We prove the existence
and uniqueness of the EPR state as a normalized, positive linear functional of
the Weyl algebra for two degrees of freedom. We then show that the EPR state
maximally violates Bell's inequalities.

</DOC>
<DOC>
<DOCNO> 7935 </DOCNO>
Mobile Bipolaron


  We explore the properties of the bipolaron in a 1D Holstein-Hubbard model
with dynamical quantum phonons. Using a recently developed variational method
combined with analytical strong coupling calculations, we compute correlation
functions, effective mass, bipolaron isotope effect and the phase diagram. The
two site bipolaron has a significantly reduced mass and isotope effect compared
to the on-site bipolaron, and is bound in the strong coupling regime up to
twice the Hubbard U naively expected. The model can be described in this regime
as an effective t-J-V model with nearest neighbor repulsion. These are the most
accurate bipolaron calculations to date.

</DOC>
<DOC>
<DOCNO> 13474 </DOCNO>
Bound states and extended states around a single vortex in the d-wave


  Making use of the Bogoliubov-de Gennes equation for the d-wave
superconductors, we investigate the quasi-particle spectrum around a single
vortex. Taking $p_F\xi=10$, we found that there are bound states which are
localized around the vortex core, and extended states which are rather uniform,
for $|E|<\Delta$ where $E$ is the quasi-particle energy and $\Delta$ is the
asymptotic value of the order parameter for away from the vortex.

</DOC>
<DOC>
<DOCNO> 68379 </DOCNO>
Thermodynamics, strange quark matter, and strange stars


  Because of the mass density-dependence, an extra term should be added to the
expression of pressure. However, it should not appear in that of energy
according to both the general ensemble theory and basic thermodynamic
principle. We give a detail derivation of the thermodynamics with
density-dependent particle masses. With our recently determined quark mass
scaling, we study strange quark matter in this new thermodynamic treatment,
which still indicates a possible absolute stability as previously found.
However, the density behavior of the sound velocity is opposite to the previous
finding, but consistent with one of our recent publication. We have also
studied the structure of strange stars using the obtained equation of state.

</DOC>
<DOC>
<DOCNO> 13755 </DOCNO>
Heat and generalized Clausius entropy of nonextensive systems


  Macroscopic nonextensive thermodynamics is studied without recourse to
microscopic statistical mechanics. It is shown that if entropy is nonextensive,
the concept of physical temperature introduced through the generalized zeroth
law of thermodynamics necessarily leads to modifications of the first law of
thermodynamics and some of thermodynamic relations including Clausius
definition of thermodynamic entropy. It is also shown, by applying this
generalized Clausius entropy to a composite nonextensive system, how the
nonextensive entropy and the quantity of heat consistently behave in an
arbitrary thermodynamic process. An important point emerging from this is that
the entropy coefficient, which connects the microscopic and macroscopic
concepts, cannot be removed from the macroscopic nonextensive theory. This fact
suggests that nonextensivity may require atomism for macroscopic thermodynamics
at a logical level.

</DOC>
<DOC>
<DOCNO> 11723 </DOCNO>
Fermionic Heisenberg Model for Spin Glasses with BCS Pairing Interaction


  In the present paper we have analysed a fermionic infinite-ranged quantum
Heisenberg spin glass (s=1/2) with a BCS coupling in real space in the presence
of an applied magnetic field. This model has been obtained by tracing out the
conducting fermions in a superconducting alloy. The magnetic field is applied
in the resulting effective model. The problem is formulated in the path
integral formalism where the spin variables are defined as bilinear
combinations of the Grassmann fields. The static approximation is used to treat
both the pairing and the spin terms together with the replica symmetry ansatz.
Henceforth, the problem can be reduced to a one site problem. The field in the
z direction, Hz, separates the order parameters in two groups: parallel and
transverse to it. We have obtained a phase diagram in T-g space with zero
transverse spin-glass ordering, g being the strength of the pairing
interaction. It has been possible to locate the transition temperature between
the normal paramagnetic phase (NP) and the phase where there is a long range
order corresponding to formation of pairs (PAIR). The transition ends at the
temperature Tf, the transition temperature between the NP phase and the spin
glass (SG) phase. Tf decreases for stronger fields allowing us to calculate the
NP-PAIR line transition even at low temperatures. The NP-PAIR transition line
has a complex dependence with g and Hz, having a tricritical point depending on
Hz from where second order transitions occur for higher values of g and first
order transitions occur for lower values of g.

</DOC>
<DOC>
<DOCNO> 100947 </DOCNO>
Coherent-state path integral calculation of the Wigner function


  We consider a set of operators hat{x}=(hat{x}_1,..., hat{x}_N) with diagonal
representatives P(n) in the space of generalized coherent states |n>;
hat{x}=int dn P(n) |n><n|. We regularize the coherent-state path integral as a
limit of a sequence of averages <.>_L over polygonal paths with L vertices
{n_1...L}. The distribution of the path centroid bar{P}=(1/L)
sum_{i=1}^{L}P(n_i) tends to the Wigner function W(x), the joint distribution
for the operators: W(x)=lim_{L->infinity} <delta(x-bar{P})>_{L}. This result is
proved in the case where the Hamiltonian commutes with hat{x}. The Wigner
function is non-positive if the dominant paths with path centroid in a certain
region have Berry phases close to odd multiples of pi. For finite L the path
centroid distribution is a Wigner function convolved with a Gaussian of
variance inversely proportional to L. The results are illustrated by numerical
calculations of the spin Wigner function from SU(2) coherent states. The
relevance to the quantum Monte Carlo sign problem is also discussed.

</DOC>
<DOC>
<DOCNO> 67800 </DOCNO>
Contributions of order ${\cal O}(m_{\rm quark}^2)$ to $K_{\ell 3}$ form


  The form factors for the $K_{\ell 3}$ semileptonic decay are computed to
order $O(p^4)$ in generalized chiral perturbation theory. The main difference
with the standard $O(p^4)$ expressions consists in contributions quadratic in
quark masses, which are described by a single divergence-free low-energy
constant, $A_3$. A new simultaneous analysis is presented for the CKM matrix
element $V_{us}$, the ratio $F_K/F_{\pi}$, $K_{\ell 3}$ decay rates and the
scalar form factor slope $\lambda_0$. This framework easily accommodates the
precise value for $V_{ud}$ deduced from superallowed nuclear $\beta$-decays.

</DOC>
<DOC>
<DOCNO> 121598 </DOCNO>
Variability of Southern T Tauri Stars I: The Continuum and the H$\beta$


  We present time series spectrophotometric observations of GQ Lupi, a typical
representative of the YY Ori subgroup of T Tauri stars that show conspicuous
inverse PCygni profiles. The data set consists of 32 exposures taken over 5 and
8 consecutive nights of May and July 1998, respectively, and covers the
spectral range of 3100 \AA~ $< \lambda < 5100 $ \AA. The region redward and
next to the Balmer jump varies significantly on a night-to-night basis and the
amplitude of such variability decreases sharply at $\lambda >$ 4600 \AA. The
Balmer continuum slope indicates that the spectral energy distribution is
governed by a gas of temperature greater than that of the stellar photosphere.
We find an anticorrelation between the veiling and the observed Balmer jump.
The time series of the redward absorption component behaves similarly to the
veiling time series. We model the emitting region by a gas of uniform
temperature and density. The models indicate that the gas densities and the
respective temperatures are strongly anticorrelated. In addition, the model
time series show that the increase in the gas density is mirrored by an
increase of the projected emitting area (filling factor). Large/small gas
densities and filling factors are characterized by high/low observed veiling.
As the accretion rate fades from night-to-night, the observed veiling
decreases, as does the gas density and the total projected emitting area.

</DOC>
<DOC>
<DOCNO> 169800 </DOCNO>
A Magnetic Resonance Force Microscopy Quantum Computer with Tellurium


  We propose a magnetic resonance force microscopy (MRFM)-based nuclear spin
quantum computer using tellurium impurities in silicon. This approach to
quantum computing combines the well-developed silicon technology with expected
advances in MRFM.

</DOC>
<DOC>
<DOCNO> 11824 </DOCNO>
Transfer matrix eigenvalues of the anisotropic multiparametric U model


  A multiparametric extension of the anisotropic U model is discussed which
maintains integrability. The R-matrix solving the Yang-Baxter equation is
obtained through a twisting construction applied to the underlying Uq(sl(2|1))
superalgebraic structure which introduces the additional free parameters that
arise in the model. Three forms of Bethe ansatz solution for the transfer
matrix eigenvalues are given which we show to be equivalent.

</DOC>
<DOC>
<DOCNO> 68790 </DOCNO>
Unified treatment of $A+B\to 0 $ and $A+A\to 0$ chemical reactions


  In this work we propose an action to describe diffusion limited chemical
reactions belonging to various classes of universality. This action is treated
through Thompson's approach and can encompass both cases where we have
segregation as in the $A+B\to 0$ reaction, as well the simplest one, namely the
$A+A\to 0$ reaction .Our results for long time and long wavelength behaviors of
the species concentrations and reaction rates agree with exact results of
Peliti for $A+A\to 0$ reaction and rigorous results of Bramson and Lebowitz for
$A+B\to 0$ reaction, with equal initial concentrations.The different classes of
universality are reflected by the obtained upper critical dimensions varying
continuously from $d_{c}=2$ in the first case to $d_{c}=4$ in the last one.
Just at the upper critical dimensions we find universal logarithmic corrections
to the mean field behavior.

</DOC>
<DOC>
<DOCNO> 71154 </DOCNO>
Time Dependent Effective Actions at Finite Temperature


  I study derivative expansions of effective actions at finite temperature,
illustrating how the standard methods are badly defined at finite temperature.
I then show that by setting up the initial conditions at a finite time, these
problems are solved.

</DOC>
<DOC>
<DOCNO> 83507 </DOCNO>
A Note on Power-Laws of Internet Topology


  The three Power-Laws proposed by Faloutsos et al(1999) are important
discoveries among many recent works on finding hidden rules in the seemingly
chaotic Internet topology. In this note, we want to point out that the first
two laws discovered by Faloutsos et al(1999, hereafter, {\it Faloutsos' Power
Laws}) are in fact equivalent. That is, as long as any one of them is true, the
other can be derived from it, and {\it vice versa}. Although these two laws are
equivalent, they provide different ways to measure the exponents of their
corresponding power law relations. We also show that these two measures will
give equivalent results, but with different error bars. We argue that for nodes
of not very large out-degree($\leq 32$ in our simulation), the first Faloutsos'
Power Law is superior to the second one in giving a better estimate of the
exponent, while for nodes of very large out-degree($> 32$) the power law
relation may not be present, at least for the relation between the frequency of
out-degree and node out-degree.

</DOC>
<DOC>
<DOCNO> 101554 </DOCNO>
The Symplectic Geometry of Polygons in the 3-sphere


  We study the symplectic geometry of the moduli spaces $M_r=M_r(\s^3)$ of
closed n-gons with fixed side-lengths in the 3-sphere. We prove that these
moduli spaces have symplectic structures obtained by reduction of the fusion
product of $n$ conjugacy classes in SU(2), denoted $C_r^n$, by the diagonal
conjugation action of SU(2). Here $C_r^n$ is a quasi-Hamiltonian SU(2)-space.
An integrable Hamiltonian system is constructed on $M_r$ in which the
Hamiltonian flows are given by bending polygons along a maximal collection of
nonintersecting diagonals. Finally, we show the symplectic structure on $M_r$
relates to the symplectic structure obtained from gauge-theoretic description
of $M_r$. The results of this paper are analogues for the 3-sphere of results
obtained for $M_r(\h^3)$, the moduli space of n-gons with fixed side-lengths in
hyperbolic 3-space \cite{KMT}, and for $M_r(\E^3)$, the moduli space of n-gons
with fixed side-lengths in $\E^3$

</DOC>
<DOC>
<DOCNO> 13571 </DOCNO>
The electronic structure of cuprates from high energy spectroscopy


  We report studies of the electronic structure and elementary excitations of
doped and undoped cuprate chains, ladders and planes. Using high energy
spectroscopies such as x-ray absorption, core level photoemission and angle
resolved photoemission spectroscopy, important information regarding the charge
distribution and hole dynamics can be obtained. The comparison of the
experimental data with suitable theoretical models sets constraints on the
parameters entering into the model calculations, and offers insight into the
important physical quantities governing the electronic structure of these
materials. Recurring themes include the importance of the dimensionality of the
Cu-O network (1D->2D) and the crucial role played by the spin-background in
determining the dynamics of low-lying excitations in these strongly correlated
systems.

</DOC>
<DOC>
<DOCNO> 119474 </DOCNO>
A new model of a tidally disrupted star


  A new semi-analytical model of a star evolving in a tidal field is proposed.
The model is a generalization of the so-called 'affine' stellar model. In our
model the star is composed of elliptical shells with different parameters and
different orientations, depending on time and on the radial Lagrangian
coordinate of the shell. The evolution equations of this model are derived from
the virial relations under certain assumptions, and the integrals of motion are
identified. It is shown that the evolution equations can be deduced from a
variational principle. The evolution equations are solved numerically and
compared quantitatively with the results of 3D numerical computations of the
tidal interaction of a star with a supermassive black hole. The comparison
shows very good agreement between the main ``integral'' characteristics
describing the tidal interaction event in our model and in the 3D computations.
Our model is effectively a one-dimensional Lagrangian model from the point of
view of numerical computations, and therefore it can be evolved numerically
$10^{2}-10^{3}$ times faster than the 3D approach allows. This makes our model
well suited for intensive calculations covering the whole parameter space of
the problem.

</DOC>
<DOC>
<DOCNO> 178878 </DOCNO>
Role of relativity and nucleon compositeness in few-body systems


  Recent progress is reviewed in four areas where new experimental data have
been obtained: proton-proton bremsstrahlung, threshold pion production in
proton-proton collisions, elastic electron-deuteron scattering and deuteron
photodisintegration at several GeV photon energy. Relativistic effects are
expected to be significant in these processes. High energy photodisintegration
suggests that partonic behavior could be relevant in subamplitudes at large
momentum transfer.

</DOC>
<DOC>
<DOCNO> 118834 </DOCNO>
A Quantitative Study of Interacting Dark Matter in Halos


  We study the evolution of Hernquist profile ``galaxies'' in the presence of
self-interacting dark matter (SIDM), where the properties of the dark matter
can be parameterized by one number, sigma-hat = sigma M/a^2 for a halo of mass
M and break radius a. While the halos form constant density cores of size a/2
on the core radius relaxation time scale core collapse begins shortly
thereafter and a steeper 1/r^2 central density cusp starts forming faster than
predicted by 2-body relaxation. The formation of the steeper central cusp is
accelerated if the cooling baryons adiabatically compress the dark matter. The
natural consequence of SIDM is to exacerbate rather than to mitigate
astrophysical problems created by dark matter density cusps.

</DOC>
<DOC>
<DOCNO> 100737 </DOCNO>
Symmetry Groups and Equivalence Transformations in the Nonlinear


  In the case of transversely only loaded shallow shells, the nonlinear
Donnell-Mushtari-Vlasov theory for large deflection of isotropic thin elastic
shells leads to a system of two coupled nonlinear forth-order partial
differential equations known as Marguerre's equations. This system involves two
arbitrary elements -- the curvature tensor of the shell middle-surface and the
function of transversal load per unit surface area. In the present note, the
point symmetry groups of Marguerre's equations are established, the
corresponding group classification problem being solved. It is shown that
Marguerre's equations are equivalent to the von Karman equations for large
deflection of plates in the time-independent case and in the time-dependent
case as well. It is also observed that the same holds true in respect of the
field equations for anisotropic shallow shells.

</DOC>
<DOC>
<DOCNO> 39864 </DOCNO>
The ratio Phi->K+K-/K0K0bar


  The ratio Phi->K+K-/K0K0bar is discussed and its present experimental value
is compared with theoretical expectations. A difference larger than two
standard deviations is observed. We critically examine a number of mechanisms
that could account for this discrepancy, which remains unexplained.
Measurements at DAPHNE at the level of the per mille accuracy can clarify
whether there exist any anomaly.

</DOC>
<DOC>
<DOCNO> 84129 </DOCNO>
On the variational principle for dust shells in General Relativity


  The variational principle for a thin dust shell in General Relativity is
constructed. The principle is compatible with the boundary-value problem of the
corresponding Euler-Lagrange equations, and leads to ``natural boundary
conditions'' on the shell. These conditions and the gravitational field
equations which follow from an initial variational principle, are used for
elimination of the gravitational degrees of freedom. The transformation of the
variational formula for spherically-symmetric systems leads to two natural
variants of the effective action. One of these variants describes the shell
from a stationary interior observer's point of view, another from the exterior
one. The conditions of isometry of the exterior and interior faces of the shell
lead to the momentum and Hamiltonian constraints. The canonical equivalence of
the mentioned systems is shown in the extended phase space. Some particular
cases are considered.

</DOC>
<DOC>
<DOCNO> 170778 </DOCNO>
Finding cliques by quantum adiabatic evolution


  Quantum adiabatic evolution provides a general technique for the solution of
combinatorial search problems on quantum computers. We present the results of a
numerical study of a particular application of quantum adiabatic evolution, the
problem of finding the largest clique in a random graph. An n-vertex random
graph has each edge included with probability 1/2, and a clique is a completely
connected subgraph. There is no known classical algorithm that finds the
largest clique in a random graph with high probability and runs in a time
polynomial in n. For the small graphs we are able to investigate (n <= 18), the
quantum algorithm appears to require only a quadratic run time.

</DOC>
<DOC>
<DOCNO> 120138 </DOCNO>
AstroMD. A multi-dimensional data analysis tool for astrophysical


  Over the past few years, the role of visualization for scientific purpose has
grown up enormously. Astronomy makes an extended use of visualization
techniques to analyze data, and scientific visualization has became a
fundamental part of modern researches in Astronomy. With the evolution of high
performance computers, numerical simulations have assumed a great role in the
scientific investigation, allowing the user to run simulation with higher and
higher resolution. Data produced in these simulations are often
multi-dimensional arrays with several physical quantities. These data are very
hard to manage and to analyze efficiently. Consequently the data analysis and
visualization tools must follow the new requirements of the research. AstroMD
is a tool for data analysis and visualization of astrophysical data and can
manage different physical quantities and multi-dimensional data sets. The tool
uses virtual reality techniques by which the user has the impression of
travelling through a computer-based multi-dimensional model. AstroMD is a
freely available tool for the whole astronomical community
(http://www.cineca.it/astromd/).

</DOC>
<DOC>
<DOCNO> 150699 </DOCNO>
Flux Stabilization of D-branes


  We explain how D-branes on group manifolds are stabilized against shrinking
by quantized worldvolume U(1) fluxes. Starting from the Born-Infeld action in
the case of the SU(2) group manifold we derive the masses, multiplicities and
spectrum of small fluctuations of these branes, and show that they agree
exactly with the predictions of conformal field theory, to all orders in the
$\alpha^\prime$ expansion. We discuss the generalization to other groups and
comment on an apparent paradox: why are the `RR charges' of these branes not
quantized?

</DOC>
<DOC>
<DOCNO> 69182 </DOCNO>
A Dynamical Principle For The Salpeter Equation


  The `Salpeter Equation' which has long been known as the 3D version of the 4D
Bethe-Salpeter Equation under the Instantaneous Approximation, has a
well-defined rationale that stems from the half-century old Markov-Yukawa
Transversality Principle (MYTP) which not only effects an exact 3D reduction
from the original (4D) BS form, but also provides an equally exact
reconstruction of the 4D BS amplitude in terms of 3D ingredients. The second
aspect which is new, opens up a vista of applications to transition amplitudes
as 4D loop integrals.
  PACS: 03.65.-w ; 03.65.Co ; 11.10.Qr ; 11.10.St Keywords: Salpeter eq;
Markov-Yukawa Transversality Principle (MYTP); Covariant Instantaneity; 3D-4D
interlinkage; Vertex fn; 4D loop integrals

</DOC>
<DOC>
<DOCNO> 68260 </DOCNO>
Open system approach to neutrino oscillations


  Neutrino oscillations are studied in the general framework of open quantum
systems by means of extended dynamics that take into account possible
dissipative effects. These new phenomena induce modifications in the neutrino
oscillation pattern that in general can be parametrized by means of six
phenomenological constants. Although very small, stringent bounds on these
parameters are likely to be given by future planned neutrino experiments.

</DOC>
<DOC>
<DOCNO> 178619 </DOCNO>
The halo of the exotic nucleus 11Li: a single Cooper pair


  If neutrons are progressively added to a normal nucleus, the Pauli principle
forces them into states of higher momentum. When the core becomes
neutron-saturated, the nucleus expels most of the wavefunction of the last
neutrons outside to form a halo, which because of its large size can have lower
momentum. It is an open question how nature stabilizes such a fragile system
and provides the glue needed to bind the halo neutrons to the core. Here we
show that this problem is similar to that of the instability of the normal
state of an electron system at zero temperature solved by Cooper, solution
which is at the basis of BCS theory of superconductivity. By mimicking this
approach using, aside from the bare nucleon-nucleon interaction, the long
wavelength vibrations of the nucleus $^{11}$Li, the paradigm of halo nuclei, as
tailored glues of the least bound neutrons, we are able to obtain a unified and
quantitative picture of the observed properties of $^{11}$Li.

</DOC>
<DOC>
<DOCNO> 12792 </DOCNO>
Probing Spin Polarization with Andreev Reflection: A Theoretical Basis


  Andreev reflection at the interface between a ferromagnet and a
superconductor has become a foundation of a versatile new technique of
measuring the spin polarization of magnetic materials. In this paper we will
briefly outline a general theory of Andreev reflection for spin-polarized
systems and arbitrary Fermi surface in two limiting cases of ballistic and
diffusive transport

</DOC>
<DOC>
<DOCNO> 8945 </DOCNO>
Heavy Fermion Stabilization of Solitons in 1+1 Dimensions


  We find static solitons stabilized by quantum corrections in a
(1+1)-dimensional model with a scalar field chirally coupled to fermions. This
model does not support classical solitons. We compute the renormalized energy
functional including one-loop quantum corrections. We carry out a variational
search for a configuration that minimizes the energy functional. We find a
nontrivial configuration with fermion number whose energy is lower than the
same number of free fermions quantized about the translationally invariant
vacuum. In order to compute the quantum corrections for a given background
field we use a phase-shift parameterization of the Casimir energy. We identify
orders of the Born series for the phase shift with perturbative Feynman
diagrams in order to renormalize the Casimir energy using perturbatively
determined counterterms. Generalizing dimensional regularization, we
demonstrate that this procedure yields a finite and unambiguous energy
functional.

</DOC>
<DOC>
<DOCNO> 102039 </DOCNO>
Geometrization of 3-dimensional orbifolds, Part I: Geometry of cone


  The main result of this paper is a precise description of the thin part of
cone manifolds with constant curvature on the smooth part, cone angles $<\pi$
and a lower diameter bound. There are two main consequences that are used in
the proof of the orbifold theorem. First, apart from a few explicit exceptions
with simple geometry and topology, cone manifolds with lower diameter bound are
thick. Second, finite volume implies finite topological type.

</DOC>
<DOC>
<DOCNO> 100268 </DOCNO>
On the use of Mellin transform to a class of q-difference-differential


  We explore the possibility of using the method of classical integral
transforms to solve a class of $q$-difference-differential equations. The
Laplace and the Mellin transform of $q$-derivatives are derived. The results
show that the Mellin transform of the $q$-derivative resembles most closely the
corresponding expression in classical analysis, and it could therefore be
useful in solving certain $q$-difference equations.

</DOC>
<DOC>
<DOCNO> 71200 </DOCNO>
gamma* gamma -> pi pi at large Q^2


  The QCD analysis of the process gamma* gamma -> pi pi at large Q^2 and small
center-of-mass energy allows one to access a new hadronic observable describing
the exclusive transition from a q qbar or g g state to a pair of mesons. A
fruitful study may be envisaged at existing machines.

</DOC>
<DOC>
<DOCNO> 123035 </DOCNO>
The Nature of Flat-Spectrum Nuclear Radio Emission in Seyfert Galaxies


  Parsec-scale VLBA imaging of five Seyfert galaxies with flat-spectrum radio
nuclei was conducted to determine whether the flat spectrum represents thermal
emission from the accretion disk/obscuring torus or nonthermal, synchrotron
self-absorbed emission. Four of the five show emission consistent with
synchrotron self-absorption, with intrinsic sizes ~0.05-0.2 pc (or 10^4
gravitational radii for a 10^8 Msun black hole for the smallest). In contrast,
NGC 4388, which was detected with MERLIN but not the VLBA, shows thermal
emission with similar properties to that detected in NGC 1068. It is notable
that the two Seyfert galaxies with detected thermal nuclear radio emission both
have large X-ray absorbing columns, suggesting that columns in excess of
\~10^{24} cm^{-2} are needed for such disks to be detectable.

</DOC>
<DOC>
<DOCNO> 12547 </DOCNO>
The Bose molecule in one dimension


  We give the Green function, momentum distribution, two-particle correlation
function, and structure factor for the bound state of N indistinguishable
bosons with an attractive delta-function interaction in one dimension, and an
argument showing that this boson "molecule" has no excited states other than
dissociation into separated pieces.

</DOC>
<DOC>
<DOCNO> 7905 </DOCNO>
Coarsening Dynamics of a Nonconserved Field Advected by a Uniform Shear


  We consider the ordering kinetics of a nonconserved scalar field advected by
a uniform shear flow. Using the Ohta-Jasnow-Kawasaki approximation, modified to
allow for shear-induced anisotropy, we calculate the asymptotic time dependence
of the characteristic length scales, L_parallel and L_perp, that describe the
growth of order parallel and perpendicular to the mean domain orientation. In
space dimension d=3 we find, up to constants, L_parallel = gamma t^{3/2},
L_perp = t^{1/2}, where gamma is the shear rate, while for d = 2 we find
L_parallel = gamma^{1/2} t (ln t)^{1/4}, L_perp = gamma^{-1/2}(ln t)^{-1/4} .
Our predictions for d=2 can be tested by experiments on twisted nematic liquid
crystals.

</DOC>
<DOC>
<DOCNO> 152114 </DOCNO>
Vacuum Brane and the Bulk Dynamics in Dilatonic Brane World


  We investigate the dynamics of vacuum brane and the bulk in dilatonic brane
world. We present exact dynamical solutions which describe the vacuum dilatonic
brane world. We find that the solution has initial singularity and singularity
at spatial infinity.

</DOC>
<DOC>
<DOCNO> 123167 </DOCNO>
Merging between a Central Massive Black Hole and a Compact Stellar


  The central bulge of M31 is observed to have two distinct brightness peaks
with the separation of $\sim$ 2 pc. Tremaine (1995) recently proposed a new
idea that the M31's nucleus is actually a single thick eccentric disk
surrounding the central super-massive black hole. In order to explore the
origin of the proposed eccentric disk, we numerically investigate the dynamical
evolution of a merger between a central massive black hole with the mass of
$\sim$ $10^7$ $M_{\odot}$ and a compact stellar system with the mass of $\sim$
$10^6$ $M_{\odot}$ and the size of a few pc in the central 10 pc of a galactic
bulge. We found that the stellar system is destroyed by strong tidal field of
the massive black hole and consequently forms a rotating nuclear thick stellar
disk. The orbit of each stellar component in the developed disk is rather
eccentric with the mean eccentricity of $\sim$ 0.5. These results imply that
the M31's nuclear eccentric disk proposed by Tremaine (1995) can be formed by
merging between a central massive black hole and a compact stellar system. We
furthermore discuss when and how a compact stellar system is transferred into
the nuclear region around a massive black hole.

</DOC>
<DOC>
<DOCNO> 116685 </DOCNO>
Structure of the density matrix providing the minimum of generalized


  For configurational space of arbitrary dimension a strict form of the
uncertainty principle has been obtained, which takes into account the
dependence of inequality limit on the effective number of pure states present
in given statistical mixture. It is shown that in a state with minimal
uncertainty the density operators eigenfunctions coincide with the stationary
wavefunctions of a multidimensional harmonic oscillator. The mixed state
obtained has a permutational symmetry which is typical for a system of
identical bosons.

</DOC>
<DOC>
<DOCNO> 121007 </DOCNO>
Radiation pressure instability as a variability mechanism in the


  Physical mechanism responsible for high viscosity in accretion disks is still
under debate. Parameterization of the viscous stress as $\alpha P$ proved to be
a successful representation of this mechanism in the outer parts of the disk,
explaining the dwarf novae and X-ray novae outbursts as due to ionization
instability. We show that this parameterization can be also adopted in the
innermost part of the disk where the adoption of the $\alpha$-viscosity law
implies the presence of the instability in the radiation pressure dominated
region. We study the time evolution of such disks. We show that the
time-dependent behavior of GRS 1915+105 can be well reproduced if
$\alpha$-viscosity disk model is calculated accurately (with proper numerical
coefficients in vertically averaged equations and with advection included), and
if the model is supplemented with (i) moderate corona dissipating 50% of energy
(ii) jet carrying luminosity-dependent fraction of energy. These necessary
modifications in the form of the presence of a corona and a jet are well
justified observationally. The model predicts outbursts at luminosity larger
than 0.16$\dot M_{Edd}$, as required, correct outburst timescales and
amplitudes, including the effect of increasing outburst timescale with mean
luminosity. This result strongly suggests that the $\alpha$-viscosity law is a
good description of the actual mechanism responsible for angular momentum
transfer also in the innermost, radiation pressure dominated part of the disk
around a black hole.

</DOC>
<DOC>
<DOCNO> 152565 </DOCNO>
Conformal partial wave analysis of AdS amplitudes for dilaton-axion


  Operator product expansions are applied to dilaton-axion four-point
functions. In the expansions of the bilocal fields $\tilde{\Phi}\tilde{\Phi}$,
$\tilde{C}\tilde{C}$ and $\tilde{\Phi}\tilde{C}$, the conformal fields which
are symmetric traceless tensors of rank $l$ and have dimensions $\delta=2+l$ or
$8+l+\eta(l)$ and $\eta(l)=\mathcal{O}(N^{-2})$ are identified. The
unidentified fields have dimension $\delta=\lambda+l+\eta(l)$ with $\lambda\geq
10$. The anomalous dimensions $\eta(l)$ are calculated at order
$\mathcal{O}(N^{-2})$ for both $2^{-{1/2}}(-\tilde{\Phi}\tilde{\Phi} +
\tilde{C}\tilde{C})$ and $2^{-{1/2}}(\tilde{\Phi}\tilde{C} +
\tilde{C}\tilde{\Phi})$ and are found to be the same, proving $U(1)_Y$
symmetry. The relevant coupling constants are given at order $\mathcal{O}(1)$.

</DOC>
<DOC>
<DOCNO> 178385 </DOCNO>
Further Comments On The Effects of Deformation on Isovector


  We present a superior proof that the results for summed strength isovector
dipole, spin dipole, and orbital dipole excitations are independent of
deformations at the Delta N = 0 level.

</DOC>
<DOC>
<DOCNO> 40090 </DOCNO>
Measurement of Direct Photon Emission in K^+ -> pi^+ pi^0 gamma Decay


  We have performed a measurement of the K^+ -> pi^+ pi^0 gamma decay and have
observed 2 X 10^4 events. The best fit to the decay spectrum gives a branching
ratio for direct photon emission of (4.7\pm0.8\pm0.3) X 10^{-6} in the pi^+
kinetic energy region of 55 to 90 MeV and requires no component due to
interference with inner bremsstrahlung.

</DOC>
<DOC>
<DOCNO> 102738 </DOCNO>
Recursive Construction for a Class of Radial Functions II - Superspace


  We extend the recursion formula for matrix Bessel functions, which we
obtained previously, to superspace. It is sufficient to do this for the unitary
orthosymplectic supergroup. By direct computations, we show that fairly
explicit results can be obtained, at least up to dimension $8\times 8$ for the
supermatrices. Since we introduce a new technique, we discuss various of its
aspects in some detail.

</DOC>
<DOC>
<DOCNO> 178976 </DOCNO>
Exact solution of the nuclear pairing problem


  In many applications to finite Fermi-systems, the pairing problem has to be
treated exactly. We suggest a numerical method of exact solution based on SU(2)
quasispin algebras and demonstrate its simplicity and practicality. We show
that the treatment of binding energies with the use of the exact pairing and
uncorrelated monopole contribution of other residual interactions can serve as
an effective alternative to the full shell-model diagonalization in spherical
nuclei. A self-consistent combination of the exactly treated pairing and
Hartree-Fock method is discussed. Results for Sn isotopes indicate a good
agreement with experimental data.

</DOC>
<DOC>
<DOCNO> 69457 </DOCNO>
Mass gap effects and higher order electroweak Sudakov logarithms


  The infrared structure of spontaneously broken gauge theories is
phenomenologically very important and theoretically a challenging problem.
Various attempts have been made to calculate the higher order behavior of large
double-logarithmic (DL) corrections originating from the exchange of
electroweak gauge bosons resulting in contradictory claims. We present results
from two loop electroweak corrections for the process $g \longrightarrow f_{\rm
R} {\bar f}_{\rm L}$ to DL accuracy. This process is ideally suited as a
theoretical model reaction to study the effect of the mass gap of the neutral
electroweak gauge bosons at the two loop level. Contrary to recent claims in
the literature, we find that the calculation performed with the physical
Standard Model fields is in perfect agreement with the results from the
infrared evolution equation method. In particular, we can confirm the
exponentiation of the electroweak Sudakov logarithms through two loops.

</DOC>
<DOC>
<DOCNO> 8483 </DOCNO>
Viscosity critical behaviour at the gel point in a 3d lattice model


  Within a recently introduced model based on the bond-fluctuation dynamics we
study the viscoelastic behaviour of a polymer solution at the gelation
threshold. We here present the results of the numerical simulation of the model
on a cubic lattice: the percolation transition, the diffusion properties and
the time autocorrelation functions have been studied. From both the diffusion
coefficients and the relaxation times critical behaviour a critical exponent k
for the viscosity coefficient has been extracted: the two results are
comparable within the errors and are in close agreement with the Rouse model
prediction and with some experimental results. In the critical region below the
transition threshold the time autocorrelation functions show a long time tail
which is well fitted by a stretched exponential decay.

</DOC>
<DOC>
<DOCNO> 72322 </DOCNO>
State of the Unification Address


  After reviewing how M-theory subsumes string theory, I report on some new and
interesting developments, focusing on the ``brane-world'': circumventing no-go
theorems for supersymmetric brane-worlds, complementarity of the Maldacena and
Randall-Sundrum pictures; self-tuning of the cosmological constant. I conclude
with the top ten unsolved problems.

</DOC>
<DOC>
<DOCNO> 80782 </DOCNO>
Perturbative construction of self-dual configurations on the torus


  We develop a perturbative expansion which allows the construction of
non-abelian self-dual SU(2) Yang-Mills field configurations on the
four-dimensional torus with topological charge 1/2. The expansion is performed
around the constant field strength abelian solutions found by 't Hooft. Next to
leading order calculations are compared with numerical results obtained with
lattice gauge theory techniques.

</DOC>
<DOC>
<DOCNO> 71715 </DOCNO>
Hydrodynamic analysis of non-central Pb+Pb collisions at 158A GeV


  We analyze non-central heavy-ion collisions at the relativistic energy within
a full (3+1) dimensional hydrodynamic model. First, the initial parameters in
the hydrodynamic model are chosen so that we reproduce the experimental data of
both the rapidity distribution and the slope of transverse mass distribution in
central Pb + Pb collisions at 158 $A$ GeV at the CERN SPS. We next study the
validity of the ansatz of wounded nucleon scaling for the initial condition of
the hydrodynamic model through analysis of the rapidity distribution of
negative pions in non-central collisions. Moreover, a simple Monte Carlo method
is introduced to exactly calculate the particle distribution from resonance
decays.

</DOC>
<DOC>
<DOCNO> 151564 </DOCNO>
Electrically Charged Topological Solitons


  Two new families of T-Dual integrable models of dyonic type are constructed.
They represent specific $A_n^{(1)}$ singular Non-Abelian Affine Toda models
having U(1) global symmetry. Their 1-soliton spectrum contains both neutral and
U(1) charged topological solitons sharing the main properties of 4-dimensional
Yang-Mills-Higgs monopoles and dyons. The semiclassical quantization of these
solutions as well as the exact counterterms and the coupling constant
renormalization are studied.

</DOC>
<DOC>
<DOCNO> 9230 </DOCNO>
"Scars" in parametrically excited surface waves


  We consider the Faraday surface waves of a fluid in a container with a
non-integrable boundary shape. We show that, at sufficiently low frequencies,
the wave patterns are ``scars'' selected by the instability of the
corresponding periodic orbits, the dissipation at the container side walls, and
interaction effects which reflect the nonlinear nature of the Faraday waves.
The results explain the observation of a limited number of scars with anomalous
strengths in recent experiments by Kudrolli, Abraham and Gollub.

</DOC>
<DOC>
<DOCNO> 67847 </DOCNO>
R-parity Violation and Neutrino Masses


  R-parity violation in the supersymmetric standard model could be the origin
of neutrino masses and mixing accounting for the atmospheric and solar neutrino
oscillations. More interestingly, this hypothesis may be tested in future
colliders by detecting lepton number violating decays of the lightest
supersymmetric particle. Here, we present a comprehensive analysis for the
determination of sneutrino vacuum expectation values from the one-loop
effective scalar potential, and also for the one-loop renormalization of
neutrino masses and mixing. Applying our results to theories with gauge
mediated supersymmetry breaking, we discuss the effects of the one-loop
corrections and how the realistic neutrino mass matrices arise.

</DOC>
<DOC>
<DOCNO> 71813 </DOCNO>
Instantaneous Bethe-Salpeter Equation: Analytic Approach for


  The instantaneous Bethe-Salpeter equation, derived from the general
Bethe-Salpeter formalism by assuming that the involved interaction kernel is
instantaneous, represents the most promising framework for the description of
hadrons as bound states of quarks from first quantum-field-theoretic
principles, that is, quantum chromodynamics. Here, by extending a previous
analysis confined to the case of bound-state constituents with vanishing
masses, we demonstrate that the instantaneous Bethe-Salpeter equation for
bound-state constituents with (definitely) nonvanishing masses may be converted
into an eigenvalue problem for an explicitly - more precisely, algebraically -
known matrix, at least, for a rather wide class of interactions between these
bound-state constituents. The advantages of the explicit knowledge of this
matrix representation are self-evident.

</DOC>
<DOC>
<DOCNO> 151183 </DOCNO>
Kaluza-Klein Consistency, Killing Vectors, and Kahler Spaces


  We make a detailed investigation of all spaces Q_{n_1... n_N}^{q_1... q_N} of
the form of U(1) bundles over arbitrary products \prod_i CP^{n_i} of complex
projective spaces, with arbitrary winding numbers q_i over each factor in the
base. Special cases, including Q_{11}^{11} (sometimes known as T^{11}),
Q_{111}^{111} and Q_{21}^{32}, are relevant for compactifications of type IIB
and D=11 supergravity. Remarkable ``conspiracies'' allow consistent
Kaluza-Klein S^5, S^4 and S^7 sphere reductions of these theories that retain
all the Yang-Mills fields of the isometry group in a massless truncation. We
prove that such conspiracies do not occur for the reductions on the Q_{n_1...
n_N}^{q_1... q_N} spaces, and that it is inconsistent to make a massless
truncation in which the non-abelian SU(n_i+1) factors in their isometry groups
are retained. In the course of proving this we derive many properties of the
spaces Q_{n_1... n_N}^{q_1... q_N} of more general utility. In particular, we
show that they always admit Einstein metrics, and that the spaces where
q_i=(n_i+1)/\ell all admit two Killing spinors. We also obtain an iterative
construction for real metrics on CP^n, and construct the Killing vectors on
Q_{n_1... n_N}^{q_1... q_N} in terms of scalar eigenfunctions on CP^{n_i}. We
derive bounds that allow us to prove that certain Killing-vector identities on
spheres, necessary for consistent Kaluza-Klein reductions, are never satisfied
on Q_{n_1... n_N}^{q_1... q_N}.

</DOC>
<DOC>
<DOCNO> 122127 </DOCNO>
Comparing and combining the Saskatoon, QMAP and COBE CMB maps


  We present a method for comparing and combining maps with different
resolutions and beam shapes, and apply it to the Saskatoon, QMAP and COBE/DMR
data sets. Although the Saskatoon and QMAP maps detect signal at the 21 sigma
and 40 sigma levels, respectively, their difference is consistent with pure
noise, placing strong limits on possible systematic errors. In particular, we
obtain quantitative upper limits on relative calibration and pointing errors.
Splitting the combined data by frequency shows similar consistency between the
Ka- and Q-bands, placing limits on foreground contamination. The visual
agreement between the maps is equally striking. Our combined QMAP+Saskatoon
map, nicknamed QMASK, is publicly available at
www.hep.upenn.edu/~xuyz/qmask.html together with its 6495x6495 noise covariance
matrix. This thoroughly tested data set covers a large enough area (648 square
degrees --- currently the largest degree-scale map available) to allow a
statistical comparison with COBE/DMR, showing good agreement.

</DOC>
<DOC>
<DOCNO> 80972 </DOCNO>
On the Doubling Phenomenon in Lattice Chern-Simons Theories


  We analyse the pure Chern-Simons theory on an Euclidean infinite lattice. We
point out that, as a consequence of its symmetries, the Chern-Simons theory
does not have an integrable kernel. Due to the linearity of the action in the
derivatives, the situation is very similar to the one arising in the lattice
formulation of fermionic theories. Doubling of bosonic degrees of freedom is
removed by adding a Maxwell term with a mechanism similar to the one proposed
by Wilson for fermionic models.

</DOC>
<DOC>
<DOCNO> 118934 </DOCNO>
Hidden Galaxies in the Fornax Cluster


  We are using the Multibeam 21cm receiver on the Parkes Telescope combined
with the optical Two degree Field spectrograph (2dF) of the Anglo-Australian
Telescope to obtain the first complete spectroscopic sample of the Fornax
cluster. In the optical the survey is unique in that all objects (both
``stars'' and ``galaxies'') within our magnitude limits (Bj=16.5 to 19.7) are
measured, producing the most complete survey of cluster members irrespective of
surface brightness. We have detected two new classes of high surface brightness
dwarf galaxy in the cluster. With 2dF we have discovered a population of very
low luminosity (Mb approx -12) objects which are unresolved from the ground and
may be the stripped nuclei of dwarf galaxies; they are unlike any known
galaxies. In a survey of the brighter (Bj=16.5 to 18) galaxies with the
FLAIR-II spectrograph we have found a number of new high surface brightness
dwarf galaxies and show that the fraction of star-forming dwarf galaxies in the
cluster is about 30 per cent, about twice that implied by earlier morphological
classifications. Our radio observations have greatly improved upon the
sensitivity of the standard Multibeam survey by using a new ``basket weave''
scanning pattern. Our initial analysis shows that we are detecting new cluster
members with HI masses of order 10-to-the-8 Msun and HI mass-to-light ratios of
1-2 Msun/Lsun.

</DOC>
<DOC>
<DOCNO> 179051 </DOCNO>
Few-Body Correlations in Fermi Systems


  I present recent results on few-body correlations in nuclear matter at finite
temperatures and densities. In particular I focus on the four-body
correlations. The alpha-particle is the strongest bound state. The
investigation is done based on effective in-medium few-body equations that
consistently include self energy corrections and Pauli blocking effects. I
address the question of four-body condensates as well.

</DOC>
<DOC>
<DOCNO> 101375 </DOCNO>
Generalized Goldstone Theorem: Automatic Imposition of the Higgs


  Standard discussions of Goldstone's theorem based on a symmetry of the action
assume constant fields and global transformations, i.e., transformations which
are independent of spacetime coordinates. By allowing for arbitrary field
distributions in a general representation of the symmetry we derive a
generalization of the standard Goldstone's theorem. When applied to gauge
bosons coupled to scalars with a spontaneously broken symmetry the generalized
theorem automatically imposes the Higgs mechanism, i.e. the gauge bosons become
massive. The other aspect of the Higgs mechanism, the disappearance of the
would-be Goldstone boson, follows directly from the generalized symmetry
condition itself. We also use our generalized Goldstone's theorem to analyze
the case of a system in which scale and conformal symmetries are both
spontaneously broken.

</DOC>
<DOC>
<DOCNO> 151528 </DOCNO>
Deformed fields and Moyal construction of deformed super Virasoro


  Studied is the deformation of super Virasoro algebra proposed by Belov and
Chaltikhian. Starting from abstract realizations in terms of the FFZ type
generators, various connections of them to other realizations are shown,
especially to deformed field representations, whose bosonic part generator is
recently reported as a deformed string theory on a noncommutative world-sheet.
The deformed Virasoro generators can also be expressed in terms of ordinary
free fields in a highly nontrivial way.

</DOC>
<DOC>
<DOCNO> 123190 </DOCNO>
Dynamical Relaxation and Massive Extrasolar Planets


  Following the suggestion of Black (1997) that some massive extrasolar planets
may be associated with the tail of the distribution of stellar companions, we
investigate a scenario in which 5 < N < 100 planetary mass objects are assumed
to form rapidly through a fragmentation process occuring in a disc or
protostellar envelope on a scale of 100 au.
  These are assumed to have formed rapidly enough through gravitational
instability or fragmentation that their orbits can undergo dynamical relaxation
on a timescale of about 100 orbits.
  Under a wide range of initial conditions and assumptions the relaxation
process ends with either (i) one potential 'hot Jupiter' plus up to two
'external' companions, i.e. planets orbiting near the outer edge of the initial
distribution; (ii) one or two 'external' planets or even none at all; (iii) one
planet on an orbit with a semi--major axis 10 to a 100 times smaller than the
outer boundary radius of the inital distribution together with an 'external'
companion. Most of the other objects are ejected and could contribute to a
population of free floating planets. Apart from the potential 'hot Jupiters',
all the bound objects are on highly eccentric orbits. We found that, apart from
the close orbiters, the probability of ending up with a planet orbiting at a
given distance from the central star increases with the distance. This is
because of the tendency of the relaxation process to lead to collisions with
the central star.
  We discuss the application of these results to some of the more massive
extrasolar planets.

</DOC>
<DOC>
<DOCNO> 119038 </DOCNO>
Halo Cores and Phase Space Densities: Observational Constraints on Dark


  We explore observed dynamical trends in a wide range of dark matter dominated
systems (about seven orders of magnitude in mass) to constrain hypothetical
dark matter candidates and scenarios of structure formation. First, we argue
that neither generic warm dark matter (collisionless or collisional) nor
self-interacting dark matter can be responsible for the observed cores on all
scales. Both scenarios predict smaller cores for higher mass systems, in
conflict with observations; some cores must instead have a dynamical origin.
Second, we show that the core phase space densities of dwarf spheroidals,
rotating dwarf and low surface brightness galaxies, and clusters of galaxies
decrease with increasing velocity dispersion like Q ~ sigma^-3 ~ M^-1, as
predicted by a simple scaling argument based on merging equilibrium systems,
over a range of about eight orders of magnitude in Q. We discuss the processes
which set the overall normalization of the observed phase density hierarchy. As
an aside, we note that the observed phase-space scaling behavior and density
profiles of dark matter halos both resemble stellar components in elliptical
galaxies, likely reflecting a similar collisionless, hierarchical origin. Thus,
dark matter halos may suffer from the same systematic departures from homology
as seen in ellipticals, possibly explaining the shallower density profiles
observed in low mass halos. Finally, we use the maximum observed phase space
density in dwarf spheroidal galaxies to fix a minimum mass for relativistically
decoupled warm dark matter candidates of roughly 700 eV for thermal fermions,
and 300 eV for degenerate fermions.

</DOC>
<DOC>
<DOCNO> 118277 </DOCNO>
Recent Advances in Binary Star Formation Using SPH


  We review recent advances in the study of binary star formation that have
been made using the smoothed particle hydrodynamics (SPH) technique. We discuss
the importance of ensuring that the Jeans mass is always resolved during a
self-gravitating SPH calculation. Even obeying this criterion, we show that it
is now possible to perform calculations which follow the collapse of a
molecular cloud core all the way to stellar densities. These calculations
resolve 7 orders of magnitude in spatial extent and 17 orders of magnitude in
density contrast. Finally, we discuss the progress that has been made in
understanding the mass-ratio distributions of binary stellar systems by
studying the evolution of protobinary systems as they accrete gas from their
surrounding envelopes.

</DOC>
<DOC>
<DOCNO> 101013 </DOCNO>
Smooth global Lagrangian flow for the 2D Euler and second-grade fluid


  We present a very simple proof of the global existence of a $C^\infty$
Lagrangian flow map for the 2D Euler and second-grade fluid equations (on a
compact Riemannian manifold with boundary) which has $C^\infty$ dependence on
initial data $u_0$ in the class of $H^s$ divergence-free vector fields for
$s>2$.

</DOC>
<DOC>
<DOCNO> 100451 </DOCNO>
The Structure of Lie Algebras and the Classification Problem for Partial


  The present paper solves completely the problem of the group classification
of nonlinear heat-conductivity equations of the form\
$u_{t}=F(t,x,u,u_{x})u_{xx} + G(t,x,u,u_{x})$. We have proved, in particular,
that the above class contains no nonlinear equations whose invariance algebra
has dimension more than five. Furthermore, we have proved that there are two,
thirty-four, thirty-five, and six inequivalent equations admitting one-, two-,
three-, four- and five-dimensional Lie algebras, respectively. Since the
procedure which we use, relies heavily upon the theory of abstract Lie algebras
of low dimension, we give a detailed account of the necessary facts. This
material is dispersed in the literature and is not fully available in English.
After this algebraic part we give a detailed description of the method and then
we derive the forms of inequivalent invariant evolution equations, and compute
the corresponding maximal symmetry algebras. The list of invariant equations
obtained in this way contains (up to a local change of variables) all the
previously-known invariant evolution equations belonging to the class of
partial differential equations under study.

</DOC>
<DOC>
<DOCNO> 70380 </DOCNO>
Radiative Corrections to Chargino Production in Electron-Positron


  We study radiative corrections to chargino production at linear colliders
with polarised electron beams. We calculate the one-loop corrected
cross-sections for polarised electon beams due to three families of quarks and
squarks, working in the $\bar{MS}$ scheme, extending our previous calculation
of the unpolarised cross-section with one-loop corrections due to the third
family of quarks and squarks. In some cases we find rather large corrections to
the tree-level cross-sections. For example for the case of right-handed
polarised electrons and large $\tan \beta$ the corrections can be of order 30%,
allowing sensitivity to the squark mass parameters.

</DOC>
<DOC>
<DOCNO> 71238 </DOCNO>
The sign of the day-night asymmetry for solar neutrinos


  A qualitative understanding of the day-night asymmetry for solar neutrinos is
provided. The greater night flux in nu_e is seen to be a consequence of the
fact that the matter effect in the sun and that in the earth have the same
sign. It is shown in the adiabatic approximation for the sun that for all
values of the mixing angle theta_V between 0 and pi/2, the night flux of
neutrinos is greater than the day flux. Only for small values of theta_V where
the adiabatic approximation badly fails does the sign of the day-night
asymmetry reverse.

</DOC>
<DOC>
<DOCNO> 100971 </DOCNO>
Connections under Symplectic Reduction


  In this note we give conditions which ensure the reduction of a symplectic
connection in the process of a Marsden-Weinstein reduction and of the reduction
of a presymplectic manifold.

</DOC>
<DOC>
<DOCNO> 70778 </DOCNO>
Discovery and Identification of W' Bosons at e+e- Colliders


  We report on studies of the sensitivity to extra gauge bosons of the
reactions e^+ e^- -> nu nubar gamma and e gamma -> nu q + X to extract
discovery limits for W' 's. The discovery potential for a W' is, for some
models, comparable to that of the LHC. These processes may be also useful for
determining W' and Z' couplings to fermions which would complement measurements
made at the Large Hadron Collider.

</DOC>
<DOC>
<DOCNO> 8466 </DOCNO>
Modelling an Imperfect Market


  We propose a simple market model where agents trade different types of
products with each other by using money, relying only on local information.
Value fluctuations of single products, combined with the condition of maximum
profit in transactions, readily lead to persistent fluctuations in the wealth
of individual agents.

</DOC>
<DOC>
<DOCNO> 69742 </DOCNO>
Lepton Number And Neutrino Masses


  I briefly review the arguments which in the 1970's convinced many theoretical
physicists to anticipate lepton number violation, and to guess a range of
neutrino masses.

</DOC>
<DOC>
<DOCNO> 122112 </DOCNO>
Magnetic fields in our Galaxy: How much do we know?


  The large scale magnetic fields of our Galaxy have been mostly revealed by
rotation measures ($RM$s) of pulsars and extragalactic radio sources. In the
disk of our Galaxy, the average field strength over a few kpc scale is about
1.8 $\mu$G, while the total field, including the random fields on smaller
scales, has a strength of about 5 $\mu$G. The local regular field, if it is
part of the large scale field of a bisymmetric form, has a pitch angle of about
$-8\degr$. There are at least three, and perhaps five, field reversals from the
Norma arm to the outer skirt of our Galaxy.

</DOC>
<DOC>
<DOCNO> 120823 </DOCNO>
The Orbital Structure of Dark Matter Halos with Gas


  With the success of the Chandra and XMM missions and the maturation of
gravitational lensing techniques, powerful constraints on the orbital structure
of cluster dark matter halos are possible. I show that the X-ray emissivity and
mass of a galaxy cluster uniquely specify the anisotropy and velocity
dispersion profiles of its dark matter halo. I consider hydrostatic as well as
cooling flow scenarios, and apply the formalism to the lensing cluster
CL0024+16 and the cooling flow cluster Abell 2199. In both cases, the model
predicts a parameter-free velocity dispersion profile that is consistent with
independent optical redshift surveys of the clusters.

</DOC>
<DOC>
<DOCNO> 68176 </DOCNO>
Baryon stopping in high energy collisions and the extrapolation of


  A new striking feature of hadron production in nuclear collisions is the
large stopping of the participating nucleons in hadron-nucleus and
nucleus-nucleus collisions. This enhanced baryon stopping can be understood
introducing new diquark breaking mechanisms in multistring models of hadron
production. Here we show, that similar diquark breaking mechanisms occur at
high energy even in hadron-hadron collisions. This effect leads to significant
changes in the extrapolation of these models to Cosmic Ray energies.

</DOC>
<DOC>
<DOCNO> 12261 </DOCNO>
Quasiperiodic Hubbard chains


  Low energy properties of half-filled Fibonacci Hubbard models are studied by
weak coupling renormalization group and density matrix renormalization group
method. In the case of diagonal modulation, weak Coulomb repulsion is
irrelevant and the system behaves as a free Fibonacci chain, while for strong
Coulomb repulsion, the charge sector is a Mott insulator and the spin sector
behaves as a uniform Heisenberg antiferromagnetic chain. The off-diagonal
modulation always drives the charge sector to a Mott insulator and the spin
sector to a Fibonacci antiferromagnetic Heisenberg chain.

</DOC>
<DOC>
<DOCNO> 102430 </DOCNO>
Restricted permutations and Chebyshev polynomials


  We study generating functions for the number of permutations in $\SS_n$
subject to two restrictions. One of the restrictions belongs to $\SS_3$, while
the other to $\SS_k$. It turns out that in a large variety of cases the answer
can be expressed via Chebyshev polynomials of the second kind.

</DOC>
<DOC>
<DOCNO> 151646 </DOCNO>
Cartan tori and ADE classification of two-dimensional topological phase


  A talk presented at International Conference ICMP-2000, London, England

</DOC>
<DOC>
<DOCNO> 72155 </DOCNO>
On the anomalous dimension for the transversity distribution


  We show that a standard calculation of the splitting function for the
nonsinglet structure function h_1 does not lead to the expected result. The
calculation is compared to the corresponding derivation of the splitting
function for the nonsinglet polarized structure function g_1. We analyze
possible explanations for the unexpected result and discuss its implications.
PACS: 11.10.Hi; 11.40.-q; 11.55.Ds; 13.88.+e

</DOC>
<DOC>
<DOCNO> 116295 </DOCNO>
Hierarchy of time scales and quasitrapping in the N-atom micromaser


  We study the dynamics of the reduced density matrix(RDM) of the field in the
micromaser. The resonator is pumped by N-atomic clusters of two-level atoms. At
each given instant there is only one cluster in the cavity. We find the
conditions of the independent evolution of the matrix elements of RDM belonging
to a (sub)diagonal of the RDM, i.e. conditions of the diagonal invariance for
the case of pumping by N-atomic clusters. We analyze the spectrum of the
evolution operator of the RDM and discover the existence of the quasitrapped
states of the field mode. These states exist for a wide range of number of
atoms in the cluster as well as for a broad range of relaxation rates. We
discuss the hierarchy of dynamical processes in the micromaser and find an
important property of the field states corresponding to the quasi-equilibrium:
these states are close to either Fock states or to a superposition of the Fock
states. A possibility to tune the distribution function of photon numbers is
discussed.

</DOC>
<DOC>
<DOCNO> 101450 </DOCNO>
On kth-order embeddings of K3 surfaces and Enriques surfaces


  We give necessary and sufficient conditions for a big and nef line bundle L
of any degree on a K3 surface or Enriques surface to be k-very ample and
k-spanned. Furthermore, we give necessary and sufficient conditions for a
spanned and big line bundle on a K3 surface to be birationally k-very ample and
birationally k-spanned, and relate these concepts to the Clifford index and
gonality of smooth curves in |L|.

</DOC>
<DOC>
<DOCNO> 116770 </DOCNO>
The Orientation of Local Spatial Reference Frames in Quantum


  Bennett et al.'s original article on quantum teleportation did not address
explicitly synchronizing the orientation of the local spatial reference frames
from and to which teleportaton occurs where the state teleported is spin 1/2
along the z axis. They wrote that only two bits of information need to be
conveyed classically where the state to be teleported concerns spin 1/2 along
the z axis. That only two bits of information need to be classically conveyed
could imply that such synchronization is not needed for it would require more
classically conveyed information. A gedankenexperiment is presented regarding
the orientation of the local spatial reference frames exploring whether such
synchronization is not needed even though it was apparently assumed by Bennett
et al. that it was required. It is often assumed that there is an absolute, as
opposed to a relative, orientation of objects in space. This assumption should
be open to empirical test, especially in view of evidence in psychology that
the orientation of objects in space is not absolute.

</DOC>
<DOC>
<DOCNO> 102184 </DOCNO>
A Lecture about classification of Lorentzian Kac-Moody algebras of the


  This is the announcement and partly the review of our results about
classification of Lorentzian Kac-Moody algebras of the rank three. One of our
results gives the classification of Lorentzian Kac-Moody algebras with
denominator identity functions which are holomorphic reflective automorphic
forms with respect to paramodular groups. Almost all of them were found in our
paper ``Automorphic forms and Lorentzian Kac-Moody algebras. Parts I, II'',
Intern. J. Math. 9 (1998), 153-275. Our main result gives classification of all
reflective meromorphic automorphic products with respect to paramodular groups.
  This is mainly a presentation of our lectures given during the Workshop:
``Applications to Quantum Field Theory'', October 23 - 27, 2000, in the Newton
Mathematical Institute at Cambridge.

</DOC>
<DOC>
<DOCNO> 84610 </DOCNO>
A Nearly Minimum Redundant Correlator Interpolation Formula for


  An absolute lower bound on the number of templates needed to keep the fitting
factor above a prescribed minimal value $\Gamma$ in correlator bank detection
of (newtonian) gravitational wave chirps from unknown inspiraling compact
binary sources is derived, resorting to the theory of quasi-bandlimited
functions in the $L^\infty$ norm. An explicit nearly-minimum redundant
cardinal-interpolation formula for the (reduced, noncoherent) correlator is
introduced. Its computational burden and statistical properties are compared to
those of the plain lattice of (reduced, noncoherent) correlators, for the same
$\Gamma$. Extension to post-newtonian models is outlined.

</DOC>
<DOC>
<DOCNO> 12057 </DOCNO>
X-ray absorption spectroscopy study of diluted magnetic semiconductors:


  We have investigated 3d electronic states of doped transition metals in II-VI
diluted magnetic semiconductors, Zn1-xMxSe (M = Mn, Fe, Co) and Zn1-xMnxY (Y =
Se, Te), using the transition-metal L2,3-edge X-ray absorption spectroscopy
(XAS) measurements. In order to explain the XAS spectra, we employed a
tetragonal cluster model calculation, which includes not only the full ionic
multiplet structure but also configuration interaction (CI). The results show
that CI is essential to describe the experimental spectra adequately,
indicating the strong hybridization between the transition metal 3d and the
ligand p orbitals. In the study of Zn1-xMnxY (Y = Se, Te), we also found
considerable spectral change in the Mn L2,3-edge XAS spectra for different
ligands, confirming the importance of the hybridization effects in these
materials.

</DOC>
<DOC>
<DOCNO> 71134 </DOCNO>
Photons and static gravity


  The influence of static gravitational field on frequency, wave-length and
velocity of photons and on the energy levels of atoms and nuclei is considered
in the most elementary way. The interconnection between these phenomena is
stressed.

</DOC>
<DOC>
<DOCNO> 102061 </DOCNO>
Divisorial contractions in dimension three which contract divisors to


  We deal with a divisorial contraction in dimension 3 which contracts its
exceptional divisor to a cA_1 point. We prove that any such contraction is
obtained by a suitable weighted blow-up.

</DOC>
<DOC>
<DOCNO> 118463 </DOCNO>
On mesogranulation, network formation and supergranulation


  We present arguments which show that in all likelihood mesogranulation is not
a true scale of solar convection but the combination of the effects of both
highly energetic granules, which give birth to strong positive divergences
(SPDs) among which we find exploders, and averaging effects of data processing.
The important role played by SPDs in horizontal velocity fields appears in the
spectra of these fields where the scale $\sim$4 Mm is most energetic; we
illustrate the effect of averaging with a one-dimensional toy model which shows
how two independent non-moving (but evolving) structures can be transformed
into a single moving structure when time and space resolution are degraded.
  The role of SPDs in the formation of the photospheric network is shown by
computing the advection of floating corks by the granular flow. The coincidence
of the network bright points distribution and that of the corks is remarkable.
We conclude with the possibility that supergranulation is not a proper scale of
convection but the result of a large-scale instability of the granular flow,
which manifests itself through a correlation of the flows generated by SPDs.

</DOC>
<DOC>
<DOCNO> 67916 </DOCNO>
Baryogenesis at Low Reheating Temperatures


  We note that the maximum temperature during reheating can be much greater
than the reheating temperature $T_r$ at which the Universe becomes radiation
dominated. We show that the Standard Model anomalous $(B+L)$-violating
processes can therefore be in thermal equilibrium for 1 GeV $\simlt T_{r}\ll
100$ GeV. Electroweak baryogenesis could work and the traditional upper bound
on the Higgs mass coming from the requirement of the preservation of the baryon
asymmetry may be relaxed. Alternatively, the baryon asymmetry may be
reprocessed by sphaleron transitions either from a $(B-L) $ asymmetry generated
by the Affleck-Dine mechanism or from a chiral asymmetry between $e_R$ and
$e_L$ in a $B-L = 0$ Universe. Our findings are also relevant to the production
of the baryon asymmetry in large extra dimension models.

</DOC>
<DOC>
<DOCNO> 118160 </DOCNO>
Pinpointing the Position of the Post-AGB Star at the Core of RAFGL 2688


  We have used infrared polarimetric imaging with NICMOS to determine precisely
the position of the star that illuminates (and presumably generated) the
bipolar, pre-planetary reflection nebula RAFGL 2688 (the Egg Nebula). The
polarimetric data pinpoint the illuminating star, which is not detected
directly at wavelengths less than or equal to 2 microns, at a position well
within the dark lane that bisects the nebula, 0.55" (about 550 AU) southwest of
the infrared peak which was previously detected at the southern tip of the
northern polar lobe. The inferred position of the central star corresponds to
the geometric center of the tips of the four principle lobes of near-infrared
H2 emission; identifying the central star at this position also reveals the
strong point symmetric structure of the nebula, as seen both in the intensity
and polarization structure of the polar lobes. The polarimetric and imaging
data indicate that the infrared peak directly detected in the NICMOS images is
a self-luminous source and, therefore, is most likely a distant binary
companion to the illuminating star. Although present theory predicts that
bipolar structure in pre-planetary and planetary nebulae is a consequence of
binary star evolution, the separation between the components of the RAFGL 2688
binary system, as deduced from these observations, is much too large for the
presence of the infrared companion to have influenced the structure of the
RAFGL 2688 nebula.

</DOC>
<DOC>
<DOCNO> 72029 </DOCNO>
$c\to u\gamma$ in the minimal supersymmetric standard model


  The minimal supersymmetric standard model (MSSM) with universal soft breaking
terms has a negligible effect on the rare $c\to u\gamma$ decay rate. We
therefore study a general model with non-universal soft breaking terms
constrained by vacuum stability and the experimental upper bound on the mass
difference of the neutral charm mesons. It turns out that gluino exchange can
enhance the standard model rate by up to two orders of magnitudes; in contrast,
the contributions from charginos and neutralinos remain at least an order of
magnitude below the QCD corrected standard model rate.

</DOC>
<DOC>
<DOCNO> 152235 </DOCNO>
Curved, extended classical solutions I. The undulating kink


  The energy of extended classical objects, such as vortices, depends on their
shape. In particular, we show that the curvature energy of a kink in two
spatial dimensions, as a prototype of extended classical solutions, is always
negative. We obtain a closed form for the curvature energy, assuming small
deviations from the straight line.

</DOC>
<DOC>
<DOCNO> 71833 </DOCNO>
Spin Effects In Diffractive Reactions


  Double spin asymmetries in the diffractive $Q \bar Q$ and $J/\Psi$
leptoproduction are discussed. It is shown that the asymmetries for
longitudinally polarized lepton and longitudinally or transversely polarized
proton can be used to study spin dependent gluon distribution of the proton at
small $x$.

</DOC>
<DOC>
<DOCNO> 121437 </DOCNO>
III Zw 2: superluminal expansion and compact lobe expansion in a Seyfert


  So far, all relativistically boosted jets with superluminal motion have only
been detected in typical radio galaxies with early type host galaxies. We have
now discovered superluminal motion in the Seyfert I galaxy III Zw 2, classified
as a spiral. The lower limit for the apparent expansion speed is 1.25 c.
Spectral and spatial evolution are closely linked. Before and after this rapid
expansion we have seen a period of virtually no expansion with an expansion
speed less than 0.04 c. However, at 15 GHz the picture is completely different.
III Zw 2 shows slow expansion ($\sim 0.6 c$) during the time of no expansion at
43 GHz and no expansion during the rapid expansion at 43 GHz. The difference
between the two frequencies is qualitatively explained by optical-depth effects
in an 'inflating- balloon model', describing the evolution of radio lobes on an
ultra-compact scale. The stop-and-go behavior could be explained by a jet
interacting with a molecular cloud or the molecular torus. Since III Zw 2 is
also part of a sample of so- called radio-intermediate quasars (RIQ), it
confirms earlier predictions of superluminal motion for this source, based on
the argument that RIQs could be relativistically boosted jets in radio-weak
quasars and Seyfert galaxies.

</DOC>
<DOC>
<DOCNO> 8599 </DOCNO>
Evidence of first-order transition between vortex glass and Bragg glass


  Phase transition between the vortex glass and the Bragg glass phases in
high-$T_{\rm c}$ superconductors in $\vec{B}\parallel\vec{c}$ is studied by
Monte Carlo simulations in the presence of point pins. A finite latent heat and
a $\delta$-function peak of the specific heat are observed, which clearly
indicates that this is a thermodynamic first-order phase transition. Values of
the entropy jump and the Lindemann number are consistent with those of melting
transitions. A large jump of the inter-layer phase difference is consistent
with the recent Josephson plasma resonance experiment of
Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+y}$ by Gaifullin {\it et al.}

</DOC>
<DOC>
<DOCNO> 119407 </DOCNO>
Acoustic Signatures in the Primary Microwave Background Bispectrum


  If the primordial fluctuations are non-Gaussian, then this non-Gaussianity
will be apparent in the cosmic microwave background (CMB) sky. With their
sensitive all-sky observation, MAP and Planck satellites should be able to
detect weak non-Gaussianity in the CMB sky. On large angular scale, there is a
simple relationship between the CMB temperature and the primordial curvature
perturbation. On smaller scales; however, the radiation transfer function
becomes more complex. In this paper, we present the angular bispectrum of the
primary CMB anisotropy that uses the full transfer function. We find that the
bispectrum has a series of acoustic peaks that change a sign, and a period of
acoustic oscillations is twice as long as that of the angular power spectrum.
Using a single non-linear coupling parameter to characterize the amplitude of
the bispectrum, we estimate the expected signal-to-noise ratio for COBE, MAP,
and Planck experiments. We find that the detection of the primary bispectrum by
any kind of experiments should be problematic for the simple slow-roll
inflationary scenarios. We compare the sensitivity of the primary bispectrum to
the primary skewness and conclude that when we can compute the predicted form
of the bispectrum, it becomes a ``matched filter'' for detecting the
non-Gaussianity in the data, and much more powerful tool than the skewness. We
also show that MAP and Planck can separate the primary bispectrum from various
secondary bispectra on the basis of the shape difference. The primary CMB
bispectrum is a test of the inflationary scenario, and also a probe of the
non-linear physics in the very early universe.

</DOC>
<DOC>
<DOCNO> 100727 </DOCNO>
Finite Quantum Groupoids and Their Applications


  We give a survey of the theory of finite quantum groupoids (weak Hopf
algebras), including foundations of the theory and applications to finite depth
subfactors, dynamical deformations of quantum groups, and invariants of knots
and 3-manifolds.

</DOC>
<DOC>
<DOCNO> 71604 </DOCNO>
Anisotropic color superconductor


  We argue that the QCD matter not far above a critical
confinement-deconfinement baryon density and low temperatures can develop
spontaneously the condensates of spin-one quark Cooper pairs. Depending upon
their color these condensates characterize two distinct anisotropic
color-superconducting phases. For them we derive the generic form of the
quasiquark dispersion laws and the gap equation. We also visualize the soft
Nambu-Goldstone modes of spontaneously broken global symmetries, and
demonstrate an unusual form of the Meissner effect.}]

</DOC>
<DOC>
<DOCNO> 70144 </DOCNO>
SUSY GUTs under Siege : Proton Decay


  SO(10) supersymmetric grand unified theories [SUSY GUTs] provide a beautiful
framework for physics beyond the standard model. Experimental measurements of
the three gauge couplings are consistent with unification at a scale $M_G \sim
3 \times 10^{16}$ GeV. In addition predictive models for fermion masses and
mixing angles have been found which fit the low energy data, including the
recent data for neutrino oscillations. SO(10) boundary conditions can be tested
via the spectrum of superparticles. The simplest models also predict neutron
and proton decay rates. In this paper we discuss nucleon decay rates and obtain
reasonable upper bounds. A clear picture of the allowed SUSY spectra as
constrained by nucleon decay is presented.

</DOC>
<DOC>
<DOCNO> 70635 </DOCNO>
Diffractive Vector Mesons in DIS: Meson Structure and QCD


  I review the modern status of QCD theory of diffractive vector meson
production with the focus on shrinkage of photons with Q2 and (Q2+mV2)$scaling,
j-plane properties of the QCD pomeron and Regge shrinkage of diffraction cone,
$s$-channel helicity non-conservation and sensitivity to spin-orbital
properties of vector mesons.

</DOC>
<DOC>
<DOCNO> 122983 </DOCNO>
STIS Ultraviolet Spectral Evidence for Outflows in Extreme Narrow-Line


  (abridged) I present and discuss the results of HST STIS observations of IRAS
13224-3809 and 1H 0707-495, two narrow-line Seyfert 1 (NLS1) galaxies. We
discovered that high-ionization UV emission lines are much broader and strongly
blueshifted compared with the low-ionization and intermediate-ionization lines,
which are relatively narrow and centered at the rest wavelength. We interpret
this as evidence that the high-ionization lines come from a wind, while the
low-ionization lines are emitted from the accretion disk or low-velocity base
of the wind. The optically thick disk blocks our view of the receding wind. We
also found that not all NLS1s display strongly blueshifted emission lines, and
the degree of asymmetry is inversely correlated with the equivalent width and
correlated with the SiIII] to CIII] ratio, a density indicator. It may also be
significant that these NLS1s display the extreme in the X-ray properties: they
have the strongest X-ray soft-excess components and the highest-amplitude,
flaring variability. We postulate that this combination of properties are all
related to a high value of L/M_BH, even among NLS1s. The high-ionization and
low-ionization lines are nearly completely kinematically separated, a fact that
allows us to study the conditions in the disk and wind separately.(...)

</DOC>
<DOC>
<DOCNO> 13164 </DOCNO>
Influence of weak anchoring on flow instabilities in nematic liquid


  We analyse the homogeneous instabilities in a nematic liquid crystal
subjected to plane steady Couette or Poiseuille flow in the case when the
director is pre-aligned perpendicular to the flow plane taking into account
weak anchoring at the confining surfaces. The critical shear rate decreases for
decreasing anchoring strength and goes to zero in the limit of torque-free
boundary conditions. For Poiseuille flow one has two types of instability
depending on the values of the azimuthal ($W_a$) and polar ($W_p$) surface
anchoring strengths. The critical line in $(W_a,W_p)$ space which separates the
two instabilities regimes is obtained.

</DOC>
<DOC>
<DOCNO> 71313 </DOCNO>
K->pipie+e- decays and chiral low-energy constants


  The branching ratios of the measured decay $K_L\to\pi^+\pi^-e^+e^-$ and of
the still unmeasured decay $K^+\to\pi^+\pi^0e^+e^-$ are calculated to
next-to-leading order in Chiral Perturbation Theory (CHPT). Recent experimental
results are used to determine two possible values of the combination
$(N^r_{16}-N_{17})$ of weak low-energy couplings (LECs) from the
$\mathcal{O}(p^4)$ chiral Lagrangian. The obtained values are compared to the
predictions of theoretical approaches to weak counterterm couplings to
distinguish between the two values. Using the favoured value of the combination
$(N^r_{16}-N_{17})$ and taking into account additional assumptions suggested by
the considered models, one obtains the branching ratio of the second decay as a
function of the unknown combination $(N^r_{14}+2N^r_{15})$ of weak low-energy
couplings. Finally, using values of the individual LECs derived from a
particular model, one predicts the branching ratio of the $K^+$ decay.

</DOC>
<DOC>
<DOCNO> 83361 </DOCNO>
Metonymy Interpretation Using X NO Y Examples


  We developed on example-based method of metonymy interpretation. One
advantages of this method is that a hand-built database of metonymy is not
necessary because it instead uses examples in the form ``Noun X no Noun Y (Noun
Y of Noun X).'' Another advantage is that we will be able to interpret
newly-coined metonymic sentences by using a new corpus. We experimented with
metonymy interpretation and obtained a precision rate of 66% when using this
method.

</DOC>
<DOC>
<DOCNO> 122274 </DOCNO>
The Discovery of Argon in Comet C/1995 O1 (Hale-Bopp)


  On 30.14 March 1997 we observed the EUV spectrum of the bright comet C/1995
O1 (Hale-Bopp) at the time of its perihelion, using our EUVS sounding rocket
telescope/spectrometer. The spectra reveal the presence H Ly beta, O+, and,
most notably, Argon. Modelling of the retrieved Ar production rates indicates
that comet Hale-Bopp is enriched in Ar relative to cosmogonic expectations.
This in turn indicates that Hale-Bopp's deep interior has never been exposed to
the 35-40 K temperatures necessary to deplete the comet's primordial argon
supply.

</DOC>
<DOC>
<DOCNO> 69192 </DOCNO>
Modelling Bose-Einstein effect from asymmetric sources in Monte Carlo


  We present some results concerning the Bose-Einstein effect in asymmetric
sources in Monte Carlo generators. A comparison of LEP data, standard JETSET
predictions and results from the weight method is given. Possible
generalization of the weight factors to an asymmetric form is considered.

</DOC>
<DOC>
<DOCNO> 7921 </DOCNO>
Thermodynamics of the spin-flop transition in a quantum XYZ chain


  A special limit of an antiferromagnetic XYZ chain was recently shown to
exhibit interesting bulk as well as surface spin-flop transitions at T=0. Here
we provide a complete calculation of the thermodynamics of the bulk transition
using a transfer-matrix-renormalization-group (TMRG) method that addresses
directly the thermodynamic limit of quantum spin chains. We also shed some
light on certain spinwave anomalies at low temperature predicted earlier by
Johnson and Bonner.

</DOC>
<DOC>
<DOCNO> 117157 </DOCNO>
Quantum Fluctuations of the Gravitational Field and Propagation of


  Quantum gravity is quite elusive at the experimental level; thus a lot of
interest has been raised by recent searches for quantum gravity effects in the
propagation of light from distant sources, like gamma ray bursters and active
galactic nuclei, and also in earth-based interferometers, like those used for
gravitational wave detection. Here we describe a simple heuristic picture of
the quantum fluctuations of the gravitational field that we have proposed
recently, and show how to use it to estimate quantum gravity effects in
interferometers.

</DOC>
<DOC>
<DOCNO> 10309 </DOCNO>
Evidence For Heavy Hole and Light Hole Current Separation in P-Type


  We investigate the transport of holes through $AlAs/In_{.10}Ga_{.90}As$
resonant tunneling diodes which utilize $In_xGa_{1-x}As$ prewells in the
emitter with $x=0,.10,$ and $.20$. The data show an increase in peak current
and bias at resonance and a concurrent increase in the peak-to-valley ratio
with increasing x. We explain this enhancement in tunneling as due to
confinement (or localiz- ation) of charges in the prewell and the formation of
direct heavy(light) hole to heavy(light) hole conduction channels as a
consequence.

</DOC>
<DOC>
<DOCNO> 118414 </DOCNO>
Jets from compact objects


  Some topics in the theory of jets are reviewed. These include jet precession,
unconfined jets, the origin of knots, the internal shock model as a unifying
theme from protostellar jets to Gamma-ray bursts, relations between the
Blandford-Znajek and MHD disk-wind models, and jet collimation in magnetic
acceleration models.

</DOC>
<DOC>
<DOCNO> 69299 </DOCNO>
Effects of R-parity violation on CP asymmetries in $\Lambda_b \to p \pi$


  We have studied new CP violating effects in $\Lambda_b \to p \pi$ decay mode,
that can arise in Minimal Supersymmetric Standard Model with R-parity
violation. We have estimated how much R-parity violation modifies the Standard
Model predictions for CP asymmetries within the present bounds. We found that
in the R-parity violating model, the rate asymmetry ($a_{cp}$) is suppressed
(about 10 times) and the asymmetry parameter $A(\alpha)$ is enhanced
(approximately $10^2$ times) with respect to the SM predictions.

</DOC>
<DOC>
<DOCNO> 84325 </DOCNO>
Black Diamonds at Brane Junctions


  We discuss the properties of black holes in brane-world scenarios where our
universe is viewed as a four-dimensional sub-manifold of some
higher-dimensional spacetime. We consider in detail such a model where
four-dimensional spacetime lies at the junction of several domain walls in a
higher dimensional anti-de Sitter spacetime. In this model there may be any
number p of infinitely large extra dimensions transverse to the brane-world. We
present an exact solution describing a black p-brane which will induce on the
brane-world the Schwarzschild solution. This exact solution is unstable to the
Gregory-Laflamme instability, whereby long-wavelength perturbations cause the
extended horizon to fragment. We therefore argue that at late times a
non-rotating uncharged black hole in the brane-world is described by a deformed
event horizon in p+4 dimensions which will induce, to good approximation, the
Schwarzschild solution in the four-dimensional brane world. When p=2, this
deformed horizon resembles a black diamond and more generally for p>2, a
polyhedron.

</DOC>
<DOC>
<DOCNO> 100878 </DOCNO>
Geometry and dynamics on the free solvable groups


  The new model for the free solvable groups of level two is given; this helps
to calculate the Poisson-Furstenberg boundary of the group.

</DOC>
<DOC>
<DOCNO> 102162 </DOCNO>
A family of *-algebras allowing Wick ordering: Fock representations and


  We consider an abstract Wick ordering as a family of relations on elements
a_i and define *-algebras by these relations. The relations are given by a
fixed operator T:h\otimes h --> h \otimes h, where h is one-particle space, and
they naturally define both a *-algebra and an inner-product space H_T, <.,.>_T.
If a_i^* denotes the adjoint, i.e., <a_i\phi,\psi>_T=<\phi,a_i^*\psi>_T, then
we identify when <.,.>_T is positive semidefinite (the positivity question). In
the case of deformations of the CCR-relations (the q_{ij}-CCR and the twisted
CCR's), we work out the universal C*-algebras A, and we prove that, in these
cases, the Fock representations of the A's are faithful.

</DOC>
<DOC>
<DOCNO> 101124 </DOCNO>
Infinite Dimensional Quantum Information Geometry


  We present the construction of an infinite dimensional Banach manifold of
quantum mechanical states on a Hilbert space H using different types of small
perturbations of a given Hamiltonian. We provide the manifold with a flat
connection, called the exponential connection, and comment on the possibility
of introducing the dual mixture connection.

</DOC>
<DOC>
<DOCNO> 178713 </DOCNO>
Nucleon-nucleon interaction in the Skyrme model


  We consider the interaction of two skyrmions in the framework of the sudden
approximation. The widely used product ansatz is investigated. Its failure in
reproducing an attractive central potential is associated with terms that
violate G-parity. We discuss the construction of alternative ans\"atze and
identify a plausible solution to the problem.

</DOC>
<DOC>
<DOCNO> 39651 </DOCNO>
Search for D0-D0B Mixing


  We report on a search for D0-D0B mixing made by studying the `wrong-sign'
process D0->K^+pi^-. The data come from an integrated luminosity of 9.0 1/fb of
e^+e^- collisions at s^(1/2) of approximately 10 GeV recorded with the CLEO
II.V detector. We measure the time integrated rate of the `wrong-sign' process
D0->K^+pi^- relative to that of the Cabibbo-favored process D0B->K^+pi^- to be
R=(0.332^{+0.063}_{-0.065}+-0.040)%. We study D0->K^+pi^- as a function of
decay time to distinguish direct doubly Cabibbo-suppressed decay from D0-D0B
mixing. The amplitudes that describe D0-D0B mixing, x' and y', are consistent
with zero. At the 95% C.L. and without assumptions concerning charge-parity
(CP) violating parameters, we find (1/2)x'^2 < 0.041% and -5.8% < y' < 1.0%.

</DOC>
<DOC>
<DOCNO> 116926 </DOCNO>
Double Kicker system in ATF


  A double kicker system which extracts the ultra-low emittance multi-bunch
beam stably from ATF damping ring was developed. The performance of the system
was studied comparing an orbit jitter with single kicker extraction in single
bunch mode. The position jitter reduction was estimated from the analysis of
the extraction orbits. The reduction was confirmed for the double kicker system
within a resolution of BPMs. More precise tuning of the system with a wire
scanner has been tried by changing a beta function at the second kicker to get
more reduction of kick angle jitter. The results of these studies are described
in detail.

</DOC>
<DOC>
<DOCNO> 84787 </DOCNO>
Blow-up for solutions of hyperbolic PDE and spacetime singularities


  An important question in mathematical relativity theory is that of the nature
of spacetime singularities. The equations of general relativity, the Einstein
equations, are essentially hyperbolic in nature and the study of spacetime
singularities is naturally related to blow-up phenomena for nonlinear
hyperbolic systems. These connections are explained and recent progress in
applying the theory of hyperbolic equations in this field is presented. A
direction which has turned out to be fruitful is that of constructing large
families of solutions of the Einstein equations with singularities of a simple
type by solving singular hyperbolic systems. Heuristic considerations indicate,
however, that the generic case will be much more complicated and require
different techniques.

</DOC>
<DOC>
<DOCNO> 121661 </DOCNO>
Far infrared observations of the southern Galactic star forming complex


  The Galactic star forming region in the southern sky, associated with IRAS
09002-4732 has been mapped simultaneously in two far infrared bands (148 & 209
um), with ~ 1' angular resolution. Fifteen sources including IRAS 08583-4719,
08589-4714, 09002-4732 and 09014-4736 have been detected, some of which are
well resolved. Taking advantage of similar beams in the two bands, a reliable
dust temperature [T(148/209)] map has been obtained, which detects colder dust
(< 30 K) in this region. The HIRES processed IRAS maps at 12, 25, 60 & 100 um
have also been used for comparison. The optical depth maps at 200 um & 100 um,
generated from these FIR data quantify the spatial distribution of the dust.
The diffuse emission from this entire region has been found to be 35 % of the
total FIR luminosity. The slope of the IMF in the mass range 4-16 M_sun has
been estimated to be -1.25^+0.75_-0.65 for this star forming complex.
  Radiative transfer models have been explored to fit available observations of
the 4 IRAS sources and extract various physical parameters for corresponding
dust-gas clouds. Whereas a constant radial density distribution is favoured in
IRAS 08583-4719, 08589-4714 & 09002-4732, the r^-1 law is inferred for IRAS
09014-4736. The dust composition is found to be similar (Silicate dominated) in
all the 4 sources. The luminosity per unit mass is found to be in the narrow
range of 44-81 L_sun/M_sun for these star forming regions.

</DOC>
<DOC>
<DOCNO> 150771 </DOCNO>
The Phase of the Scattering Matrix


  Vacuum polarization in external fields is treated by way of calculating -
exactly and then perturbatively - the phase of the quantum scattering matrix in
the Shale-Stinespring approach to field theory. The link between the
Shale-Stinespring method and the Epstein-Glaser renormalization procedure is
highlighted.

</DOC>
<DOC>
<DOCNO> 122779 </DOCNO>
VLT Deep I-band Surface Brightness Fluctuations of IC 4296


  From theoretical predictions, the introduction of 8-m class telescopes
permits one to extend Surface Brightness Fluctuations measurements from the
ground to ~7000 km/s, with a precision that is comparable to current
space-based measurements. We have measured I--band SBF in IC 4296 in Abell 3565
cz~3630 km/s with the ESO Very Large Telescope. Adopting the Tonry et al.
(2000) calibration for I-band SBF we determined a distance modulus of (I_o,k -
M_I)=33.44 +/- 0.17 mag corresponding to a galaxy distance of 49 +/- 4 Mpc.
This result is consistent with the HST observation from Lauer et al. (1998):
(I_F814 - M_F814) = 33.47 +/- 0.13 mag.

</DOC>
<DOC>
<DOCNO> 100300 </DOCNO>
Nilpotentization of the kinematics of the n-trailer system at singular


  We propose in this paper a constructive procedure that transforms locally,
even at singular configurations, the kinematics of a car towing trailers into
Kumpera-Ruiz normal form. This construction converts the nonholonomic motion
planning problem into an algebraic problem (the resolution of a system of
polynomial equations), which we illustrate by steering the two-trailer system
in a neighborhood of singular configurations. We show also that the n-trailer
system is a universal local model for all Goursat structures and that all
Goursat structures are locally nilpotentizable.

</DOC>
<DOC>
<DOCNO> 14063 </DOCNO>
Mixing of superconducting $d_{x^2-y^2}$ state with s-wave states for


  We study the order parameter for mixed-symmetry states involving a major
$d_{x^2-y^2}$ state and various minor s-wave states ($s$, $s_{xy}$, and
$s_{x^2+y^2}$) for different filling and temperature for mixing angles 0 and
$\pi/2$. We employ a two-dimensional tight-binding model incorporating
second-neighbor hopping for tetragonal and orthorhombic lattice. There is
mixing for the symmetric $s$ state both on tetragonal and orthorhombic lattice.
The $s_{xy}$ state mixes with the $d_{x^2-y^2}$ state only on orthorhombic
lattice. The $s_{x^2+y^2}$ state never mixes with the $d_{x^2-y^2}$ state. The
temperature dependence of the order parameters is also studied.

</DOC>
<DOC>
<DOCNO> 68180 </DOCNO>
Neutrino oscillation, SUSY GUT and B decay


  Effects of supersymmetric particles on flavor changing neutral current and
lepton flavor violating processes are studied in the supersymmetric SU(5) grand
unified theory with right-handed neutrino supermultiplets. Using input
parameters motivated by neutrino oscillation, it is shown that the
time-dependent CP asymmetry of radiative B decay can be as large as 30% when
the $\tau \to \mu \gamma$ branching ratio becomes close to the present
experimental upper bound. We also show that the $B_s$--$\bar{B}_s$ mixing can
be significantly different from the presently allowed range in the standard
model.

</DOC>
<DOC>
<DOCNO> 69935 </DOCNO>
Integrability of twist-three evolution equations in QCD


  We describe a recent progress in finding solutions to three-particle
evolution equations at leading order in the QCD coupling constant for
multiparton correlation functions based on the integrability of corresponding
interaction Hamiltonians.

</DOC>
<DOC>
<DOCNO> 84752 </DOCNO>
Enlarged quintessence cosmology


  We show that the combination of a fluid with a bulk dissipative pressure and
quintessence matter can simultaneously drive an accelerated expansion phase and
solve the coincidence problem of our current Universe. We then study some
scenarios compatible with the observed cosmic acceleration.

</DOC>
<DOC>
<DOCNO> 178417 </DOCNO>
Generator Coordinate Method Calculations for Ground and First Excited


  The main characteristics of the ground and, in particular, the first excited
monopole state in the $^{4}$He, $^{16}$O and $^{40}$Ca nuclei are studied
within the generator coordinate method using Skyrme-type effective forces and
three construction potentials, namely the harmonic-oscillator, the square-well
and Woods-Saxon potentials. Calculations of density distributions, radii,
nucleon momentum distributions, natural orbitals, occupation numbers and
depletions of the Fermi sea, as well as of pair density and momentum
distributions are carried out. A comparison of these quantities for both ground
and first excited monopole states with the available empirical data and with
the results of other theoretical methods are given and discussed in detail.

</DOC>
<DOC>
<DOCNO> 119562 </DOCNO>
The response of a turbulent accretion disc to an imposed epicyclic


  We excite an epicyclic motion, whose amplitude depends on the vertical
position, $z$, in a simulation of a turbulent accretion disc. An epicyclic
motion of this kind may be caused by a warping of the disc. By studying how the
epicyclic motion decays we can obtain information about the interaction between
the warp and the disc turbulence. A high amplitude epicyclic motion decays
first by exciting inertial waves through a parametric instability, but its
subsequent exponential damping may be reproduced by a turbulent viscosity. We
estimate the effective viscosity parameter, $\alpha_{\rm v}$, pertaining to
such a vertical shear. We also gain new information on the properties of the
disc turbulence in general, and measure the usual viscosity parameter,
$\alpha_{\rm h}$, pertaining to a horizontal (Keplerian) shear. We find that,
as is often assumed in theoretical studies, $\alpha_{\rm v}$ is approximately
equal to $\alpha_{\rm h}$ and both are much less than unity, for the field
strengths achieved in our local box calculations of turbulence. In view of the
smallness ($\sim 0.01$) of $\alpha_{\rm v}$ and $\alpha_{\rm h}$ we conclude
that for $\beta = p_{\rm gas}/p_{\rm mag} \sim 10$ the timescale for diffusion
or damping of a warp is much shorter than the usual viscous timescale. Finally,
we review the astrophysical implications.

</DOC>
<DOC>
<DOCNO> 122901 </DOCNO>
Protoneutron star in the Relativistic Mean - Field Theory


  In this review the basic properties of nonrotating and slowly rotating
protoneutron stars in the relativistic mean-field approach are discussed. The
equation of state is the main input to the structure equations. The TM1
parameter set extended to the case of finite temperature is used to obtain the
mass-radius relation for protoneutron stars. The occurrence of unstable areas
in the mass-radius relation are presented. This allows for the existence of
distinctively different evolutionary of tracks of the protoneutron stars. The
low density protoneutron star configurations are estimated. The obtained stable
configurations for the fixed lepton number Y_L=0.4 are compared with ones
obtained for the fixed proton fraction Y_P=0.1776.

</DOC>
<DOC>
<DOCNO> 118117 </DOCNO>
The Role of H2 Molecules in Cosmological Structure Formation


  We review the relevance of H2 molecules for structure formation in cosmology.
Molecules are important at high redshifts, when the first collapsed structures
appear with typical temperatures of a few hundred Kelvin. In these chemically
pristine clouds, radiative cooling is dominated H2 molecules. As a result, H2
``astro-chemistry'' is likely to determine the epoch when the first
astrophysical objects appear. We summarize results of recent three-dimensional
simulations. A discussion of the effects of feedback, and implications for the
reionization of the universe is also given.

</DOC>
<DOC>
<DOCNO> 178838 </DOCNO>
What can we learn from Nuclear Matter Instabilities?


  We discuss the features of instabilities in binary systems, in particular,
for asymmetric nuclear matter. We show its relevance for the interpretation of
results obtained in experiments and in "ab initio" simulations of the reaction
between $^{124}Sn+^{124}Sn$ at 50AMeV.}

</DOC>
<DOC>
<DOCNO> 100444 </DOCNO>
A Krein-Like Formula for Singular Perturbations of Self-Adjoint


  Given a self-adjoint operator $A:D(A)\subseteq\calH\to\calH$ and a continuous
linear operator $\tau:D(A)\to\X$ with Range$ \tau'\cap\calH' ={0}$, $\X$ a
Banach space, we explicitly construct a family $A^\tau_\Theta$ of self-adjoint
operators such that any $A^\tau_\Theta$ coincides with the original $A$ on the
kernel of $\tau$. Such a family is obtained by giving a Kre\u\i n-like formula
where the role of the deficiency spaces is played by the dual pair $(\X,\X')$;
the parameter $\Theta$ belongs to the space of symmetric operators from $\X'$
to $\X$. When $\X=\C$ one recovers the ``$\calH_{-2}$ -construction'' of
Kiselev and Simon and so, to some extent, our results can be regarded as an
extension of it to the infinite rank case. Considering the situation in which
$\calH=L^2(\RE^n)$ and $\tau$ is the trace (restriction) operator along some
null subset, we give various applications to singular perturbations of non
necessarily elliptic pseudo-differential operators, thus unifying and extending
previously known results.

</DOC>
<DOC>
<DOCNO> 12598 </DOCNO>
Volume change of bulk metals and metal clusters due to spin-polarization


  The stabilized jellium model (SJM) provides us a method to calculate the
volume changes of different simple metals as a function of the spin
polarization, $\zeta$, of the delocalized valence electrons. Our calculations
show that for bulk metals, the equilibrium Wigner-Seitz (WS) radius, $\bar
r_s(\zeta)$, is always a n increasing function of the polarization i.e., the
volume of a bulk metal always increases as $\zeta$ increases, and the rate of
increasing is higher for higher electron density metals. Using the SJM along
with the local spin density approximation, we have also calculated the
equilibrium WS radius, $\bar r_s(N,\zeta)$, of spherical jellium clusters, at
which the pressure on the cluster with given numbers of total electrons, $N$,
and their spin configuration $\zeta$ vanishes. Our calculations f or Cs, Na,
and Al clusters show that $\bar r_s(N,\zeta)$ as a function of $\zeta$ behaves
differently depending on whether $N$ corresponds to a closed-shell or an
open-shell cluster. For a closed-shell cluster, it is an increasing function of
$\zeta$ over the whole range $0\le\zeta\le 1$, whereas in open-shell clusters
it has a decreasing behavior over the range $0\le\zeta\le\zeta_0$, where
$\zeta_0$ is a polarization that the cluster has a configuration consistent
with Hund's first rule. The resu lts show that for all neutral clusters with
ground state spin configuration, $\zeta_0$, the inequality $\bar
r_s(N,\zeta_0)\le\bar r_s(0)$ always holds (self-compression) but, at some
polarization $\zeta_1>\zeta_0$, the inequality changes the direction
(self-expansion). However, the inequality $\bar r_s(N,\zeta)\le\bar r_s(\zeta)$
always holds and the equality is achieved in the limit $N\to\infty$.

</DOC>
<DOC>
<DOCNO> 151010 </DOCNO>
Gauging the Full R-Symmetry Group in Five-dimensional, N=2


  We show that certain five dimensional, N=2 Yang-Mills/Einstein supergravity
theories admit the gauging of the full R-symmetry group, SU(2)_R, of the
underlying N=2 Poincare superalgebra. This generalizes the previously studied
Abelian gaugings of U(1)_R subgroup of SU(2)_R and completes the construction
of the most general vector and tensor field coupled five dimensional N=2
supergravity theories with gauge interactions. The gauging of SU(2)_R turns out
to be possible only in special cases, and leads to a new type of scalar
potential. For a large class of these theories the potential does not have any
critical points.

</DOC>
<DOC>
<DOCNO> 11589 </DOCNO>
Proximity Effects and Quantum Dissipation in the Chains of


  We argue that the results of recent scanning tunneling microscopy,
angle-resolved photoemission and infrared spectroscopy experiments on the CuO
chains of YBa$_2$Cu$_3$O$_{6+x}$ are consistently explained within a proximity
model by the interplay of a coherent chain-plane and an incoherent interchain
coupling. We show that the CuO$_2$ planes act as an ohmic heat bath for the
electronic degrees of freedom in the chains which induces a substantial quantum
dissipation. Below the planar $T_c$, charge excitations in the chains acquire a
universal superconducting gap whose phase and magnitude are momentum dependent.
We predict that the magnitude of this gap varies non-monotonically with the
hole concentration in the chains.

</DOC>
<DOC>
<DOCNO> 70193 </DOCNO>
On Radiative $\phi \to \eta \gamma$, $\phi \to \eta^\prime \gamma$


  We use QCD sum-rules to study the decays $\phi \to \eta \gamma$ and $\phi \to
\eta^\prime \gamma$, obtaining ${\cal B}(\phi \to \eta \gamma)=(1.15 \pm 0.2)
10^{-2}$ and ${\cal B}(\phi \to \eta^\prime \gamma)=(1.18 \pm 0.4) 10^{-4}$, in
very good agreement with existing experimental data. We also discuss the issue
of $\eta-\eta^\prime$ mixing, predicting the $\eta$ and $\eta^\prime$ decay
constants in a mixing scheme in the quark-flavour basis.

</DOC>
<DOC>
<DOCNO> 100150 </DOCNO>
An asymptotic expansion for a ratio of products of gamma functions


  An asymptotic expansion of a ratio of products of gamma functions is derived.
It generalizes a formula which was stated by Dingle, first proved by Paris, and
recently reconsidered by Olver.

</DOC>
<DOC>
<DOCNO> 102083 </DOCNO>
On Algorithmic Equiresolution and Stratification of Hilbert Schemes


  Given an algorithm of resolution of singularities satisfying certain
conditions (``good algorithms''), natural notions of simultaneous algorithmic
resolution, or equiresolution, for families of embedded schemes (parametrized
by a reduced scheme $T$) are proposed. It is proved that these conditions are
equivalent. Something similar is done for families of sheaves of ideals, here
the goal is algorithmic simultaneous principalization. A consequence is that
given a family of embedded schemes over a reduced $T$, this parameter scheme
can be naturally expressed as a disjoint union of locally closed sets $T_{j}$,
such that the induced family on each part $T_{j}$ is equisolvable. In
particular, this can be applied to the Hilbert scheme of a smooth projective
variety; in fact, our result shows that, in characteristic zero, the underlying
topological space of any Hilbert scheme parametrizing embedded schemes can be
naturally stratified in equiresolvable families.

</DOC>
<DOC>
<DOCNO> 11077 </DOCNO>
The Free Energy Surface of Supercooled Water


  We present a detailed analysis of the free energy surface of a well
characterized rigid model for water in supercooled states. We propose a
functional form for the liquid free energy, supported by recent theoretical
predictions [Y. Rosenfeld and P. Tarazona, Mol. Phys. {\bf 95}, 141 (1998)],
and use it to locate the position of a liquid-liquid critical point at $T_{C'}
= 130 \pm 5$~K, $P_{C'}=290\pm 30$MPa, and $\rho_{C'} = 1.10 \pm
0.03$~g/cm$^3$. The observation of the critical point strengthens the
possibility that SPC/E water may undergo a liquid-liquid phase transition.
Finally, we discuss the possibility that the approach to the liquid-liquid
critical point could be pre-empted by the glass transition.

</DOC>
<DOC>
<DOCNO> 13591 </DOCNO>
An effective lowest Landau level treatment of demagnetization in


  Demagnetization, which is inherently present in the magnetic response of
small finite-size superconductors, can be accounted for by an effective
$\kappa$ within a two-dimensional lowest Landau level approximation of the
Ginzburg-Landau functional. We show this by comparing the equilibrium
magnetization of superconducting mesoscopic disks obtained from the numerical
solution of the three-dimensional Ginzburg-Landau equations with that obtained
in the ``effective'' LLL approximation.

</DOC>
<DOC>
<DOCNO> 100046 </DOCNO>
Whitehead doubling persists


  Even though the (untwisted) Whitehead doubling operation kills all known
abelian invariants of knots (and makes them topologically slice), we show that
it does not kill the rational function that equals to the 2-loop part of the
Kontsevich integral.

</DOC>
<DOC>
<DOCNO> 12539 </DOCNO>
Critical dynamics of an interacting magnetic nanoparticle system


  Effects of dipole-dipole interactions on the magnetic relaxation have been
investigated for three Fe-C nanoparticle samples with volume concentrations of
0.06, 5 and 17 vol%. While both the 5 and 17 vol% samples exhibit collective
behavior due to dipolar interactions, only the 17 vol% sample displays critical
behavior close to its transition temperature. The behaviour of the 5 vol%
sample can be attributed to a mixture of collective and single particle
dynamics.

</DOC>
<DOC>
<DOCNO> 150768 </DOCNO>
Refining the anomaly consistency condition


  In the extended antifield formalism, a quantum BRST differential for
anomalous gauge theories is constructed. Local BRST cohomological classes are
characterized, besides the form degree and the ghost number, by the length of
their descents and of their lifts, and this both in the standard and the
extended antifield formalism. It is shown that during the BRST invariant
renormalization of a local BRST cohomological class, the anomaly that can
appear is constrained to be a local BRST cohomological class with a shorter
descent and a longer lift than the given class. As an application of both
results, a simple approach to the Adler-Bardeen theorem for the non abelian
gauge anomaly is proposed. It applies independently of the gauge fixing, of
power counting restrictions and does not rely on the use of the Callan-Symanzik
equation.

</DOC>
<DOC>
<DOCNO> 9867 </DOCNO>
Umklapp Scattering and Heat Conductivity of Superlattices


  The mean free path of phonons in superlattices is estimated. It is shown to
be strongly dependent on the superlattice period due to the Umklapp scattering
in subbands. It first falls with increasing the superlattice period until it
becomes comparable with the latter after what it rises back to the bulk value.
Similar behavior is expected of heat conductivity, which is proportional to the
mean free path.

</DOC>
<DOC>
<DOCNO> 102395 </DOCNO>
The Volterra lattice as a gradient flow


  The Volterra lattice is considered. New gradient interpretation for this
dynamical system is proposed. This interpretation seems to be more natural than
existing ones.

</DOC>
<DOC>
<DOCNO> 70737 </DOCNO>
Soft gluons and gauge-invariant subtractions in NLO parton-shower Monte


  We address the problem of decomposing graphs in perturbative QCD into terms
associated with particular regions. Motivated by asking how to incorporate
next-to-leading order (NLO) QCD corrections in parton-shower algorithms, we
require that: (a) The integrand for the hard part is to be integrable even if
the corrections are applied to a process that is not infrared and collinear
safe. (b) The splitting between the terms should be defined gauge-invariantly.
(c) The dependence on cut-offs should obey homogeneous evolution equations. In
the context of one-gluon-emission graphs for deep inelastic scattering, we
explain a subtractive technique that is based on gauge-invariant Wilson-line
operators. Appropriate organization of subtractions involving the soft region
allows a connection to previous work where evolution equations with respect to
the directions of the Wilson lines have been derived.

</DOC>
<DOC>
<DOCNO> 102834 </DOCNO>
Decoupling Braided Tensor Factors


  We briefly report on our result that the braided tensor product algebra of
two module algebras $A_1,A_2$ of a quasitriangular Hopf algebra $H$ is equal to
the ordinary tensor product algebra of $H_1$ with a subalgebra isomorphic to
$A_2$ and commuting with $A_1$, provided there exists a realization of $H$
within $A_1$. As applications of the theorem we consider the braided tensor
product algebras of two or more quantum group covariant quantum spaces or
deformed Heisenberg algebras.

</DOC>
<DOC>
<DOCNO> 13482 </DOCNO>
Simplest random K-satisfiability problem


  We study a simple and exactly solvable model for the generation of random
satisfiability problems. These consist of $\gamma N$ random boolean constraints
which are to be satisfied simultaneously by $N$ logical variables. In
statistical-mechanics language, the considered model can be seen as a diluted
p-spin model at zero temperature. While such problems become extraordinarily
hard to solve by local search methods in a large region of the parameter space,
still at least one solution may be superimposed by construction. The
statistical properties of the model can be studied exactly by the replica
method and each single instance can be analyzed in polynomial time by a simple
global solution method. The geometrical/topological structures responsible for
dynamic and static phase transitions as well as for the onset of computational
complexity in local search method are thoroughly analyzed. Numerical analysis
on very large samples allows for a precise characterization of the critical
scaling behaviour.

</DOC>
<DOC>
<DOCNO> 84177 </DOCNO>
A Note on Singular Instantons


  We point out the existence of some singular, radial, spin-0 instantons for
curvature-quadratic gravity theories. They are complex.

</DOC>
<DOC>
<DOCNO> 122290 </DOCNO>
Galactic Disk Warps


  This review addresses recent developments in the field of disk galaxy warps.
Both results from a new HI survey of edgeon disk galaxies, and of simulations
of the interaction between a disk+halo and an orbiting satelite, will be
discussed.

</DOC>
<DOC>
<DOCNO> 120777 </DOCNO>
Optimizing ISOCAM data processing using spatial redundancy


  We present new data processing techniques that allow to correct the main
instrumental effects that degrade the images obtained by ISOCAM, the camera on
board the Infrared Space Observatory (ISO). Our techniques take advantage of
the fact that a position on the sky has been observed by several pixels at
different times. We use this information (1) to correct the long term variation
of the detector response, (2) to correct memory effects after glitches and
point sources, and (3) to refine the deglitching process. Our new method allows
the detection of faint extended emission with contrast smaller than 1% of the
zodiacal background. The data reduction corrects instrumental effects to the
point where the noise in the final map is dominated by the readout and the
photon noises. All raster ISOCAM observations can benefit from the data
processing described here. These techniques could also be applied to other
raster type observations (e.g. ISOPHOT or IRAC on SIRTF).

</DOC>
<DOC>
<DOCNO> 152621 </DOCNO>
On Superconnections and the Tachyon Effective Action


  We propose a form of the effective action of the tachyon and gauge fields for
brane-antibrane systems and non-BPS Dp-branes, written in terms of the
supercurvature. Kink and vortex solutions with constant infinite gauge field
strength reproduce the exact tensions of the lower-dimensional D-branes. We
discuss the relation to BSFT and other models in the literature.

</DOC>
<DOC>
<DOCNO> 150581 </DOCNO>
Implications of N = 2 Superconformal Symmetry


  We review recent results on the general structure of two- and three- point
functions of the supercurrent and the flavor current of N = 2 superconformal
field theories.

</DOC>
<DOC>
<DOCNO> 121131 </DOCNO>
Raman-Scattering Wings of H alpha in Symbiotic Stars


  Nussbaumer et al. (1989) proposed that broad H$\alpha$ wings can be formed
through Raman scattering of Ly$\beta$ photons, and in this Letter we argue that
the H$\alpha$ wings prevalently seen in symbiotic stars may be indeed formed in
this way. Assuming a flat incident UV radiation around Ly$\beta$, we generate
template wing profiles around H$\alpha$ that are formed through Raman
scattering in a plane-parallel H~I region. We perform profile fitting analyses
to show that the template wing profiles are in excellent agreement with the
observed ones that are provided by van Winckel et al. (1993) and Ivison et al.
(1994). The wing flux is determined by the scattering H~I column density and
the incident Ly$\beta$ flux strength and profile. From our profile analysis it
is proposed that the Raman scattering component may be identified with the
neutral envelope with a column density ranging $10^{18-20} {\rm cm^{-2}}$ that
surrounds the binary system. We briefly discuss alternative candidates for the
wing formation mechanism and observational implications of Raman scattering in
symbiotic stars and in other astronomical objects including planetary nebulae,
post AGB stars and active galactic nuclei.

</DOC>
<DOC>
<DOCNO> 118341 </DOCNO>
On the universality of the spectrum of cosmic rays accelerated at highly


  A small error was corrected.

</DOC>
<DOC>
<DOCNO> 84135 </DOCNO>
Generalised hyperbolicity in space-times with conical singularities


  It is shown that the space-time with a conical singularity, which describes a
thin cosmic string, is hyperbolic in the sense that a unique H^1 solution
exists to the initial value problem for the wave equation with a certain class
of initial data.

</DOC>
<DOC>
<DOCNO> 99846 </DOCNO>
Hodge integrals and Hurwitz numbers via virtual localization


  Ekedahl, Lando, Shapiro, and Vainshtein announced a remarkable formula
expressing Hurwitz numbers (counting covers of the projective line with
specified simple branch points, and specified branching over one other point)
in terms of Hodge integrals. We give a proof of this formula using virtual
localization on the moduli space of stable maps, and describe how the proof
could be simplified by the proper algebro-geometric definition of a "relative
space".

</DOC>
<DOC>
<DOCNO> 100652 </DOCNO>
Small cones of m-hemimetrics


  We introduce polyhedral cones associated with $m$-hemimetrics on $n$ points,
and, in particular, with $m$-hemimetrics coming from partitions of an $n$-set
into $m+1$ blocks. We compute generators and facets of the cones for small
values of $m,n$ and study their skeleton graphs.

</DOC>
<DOC>
<DOCNO> 117654 </DOCNO>
Structure of the globular cluster M15 and constraints on a massive


  Globular clusters could harbor massive central black holes (BHs), just as
galaxies do. So far, no unambiguous detection of a massive BH has been reported
for any globular cluster. However, the dense core-collapsed cluster M15 seems
to be a good candidate. I review the available photometric and kinematic data
for this cluster. Both are consistent with a BH of approximately 2000 solar
masses, although such a BH is not unambiguously required by the data. I discuss
some ongoing studies with Keck and HST which should shed more light on this
issue in the coming years.

</DOC>
<DOC>
<DOCNO> 102150 </DOCNO>
Representations of fundamental groups of algebraic manifolds and their


  We use pluriharmonic maps to study representations of fundamental groups of
algebraic manifolds. This approach is functorial in the sense that the
restriction of such a map to a fiber of a fibration remains pluriharmonic, and
on this basis, we can investigate the relation between the properties of the
original representation and what can be inferred by restricting it to the
fibers of a fibration.

</DOC>
<DOC>
<DOCNO> 178536 </DOCNO>
The Longitudinal and Transverse responses in inclusive electron


  The longitudinal and transverse nuclear responses to inclusive electron
scattering reactions are analyzed within the Random Phase Approximation (RPA)
framework. Several residual interactions are considered and it is shown that
the exchange terms in the RPA make very difficult to find an effective residual
interaction capable of reproducing simultaneously the quasielastic peak of both
the longitudinal and transverse responses. By means of a simplified model it is
illustrated that the residual interaction used in a ring approximation must
fulfill some restrictions in order to qualitatively reproduce the full RPA
results.

</DOC>
<DOC>
<DOCNO> 13555 </DOCNO>
Non-Gaussian Effects on Domain Growth


  The vacuum two-point function is calculated beyond the Gaussian approximation
during the second order phase transition. It is found that the correlation
function is dominated by the Gaussian term immediately after the phase
transition but later is taken over by non-Gaussian terms as the spinodal
instability continues. The non-Gaussian effects lead to larger size of domains
and may imply a smaller density of topological defects than that predicted by
the Hartree-Fock approximation.

</DOC>
<DOC>
<DOCNO> 152581 </DOCNO>
Aharonov-Bohm Effect in Noncommutative Spaces


  The Aharonov-Bohm effect on the noncommutative plane is considered.
Developing the path integral formulation of quantum mechanics, we find the
propagation amplitude for a particle in a noncommutative space. We show that
the corresponding shift in the phase of the particle propagator due to the
magnetic field of a thin solenoid receives certain gauge invariant corrections
because of the noncommutativity. Evaluating the numerical value for this
correction, an upper bound for the noncommutativity parameter is obtained.

</DOC>
<DOC>
<DOCNO> 39982 </DOCNO>
Naturalness Reach of the Large Hadron Collider in Minimal Supergravity


  We re-analyse the prospects of discovering supersymmetry at the LHC, in order
to re-express coverage in terms of a fine-tuning parameter and to extend the
analysis to scalar masses (m_0) above 2 TeV.
 We use minimal supergravity (mSUGRA) unification assumptions for the SUSY
breaking parameters. The discovery reach at high m_0 is of renewed interest
because this region has recently been found to have a focus point, leading to
relatively low fine-tuning, and because it remains uncertain how much of the
region can be ruled out due to lack of radiative electroweak symmetry breaking.
  The best fine tuning reach is found in a mono-leptonic channel, where for
mu>0, A_0=0 and tan beta=10
 (within the focus point region), and a top mass of 174 GeV, all points in
mSUGRA with m_0 < 4000 GeV, with a fine tuning measure up to 210 (500) are
covered by the search, where the definition of fine-tuning excludes (includes)
the contribution from the top Yukawa coupling. Even for arbitrarily high m_0,
mSUGRA can be discovered through gaugino events, provided the gaugino mass
parameter M_1/2 < 460 GeV. In this region, the mono-leptonic channel still
provides the best reach.

</DOC>
<DOC>
<DOCNO> 122937 </DOCNO>
Blazars in Low-Luminosity and Radio-Weak AGN?


  Typical blazars seem to be associated with FR I and FR II radio galaxies and
radio-loud quasars. However, what happens at lower powers? Do blazars exist in
low-luminosity AGN or do they exist in radio-quiet AGN? A recent detection of
superluminal motion in a supposedly radio-quiet Seyfert raises the question
whether beaming can play an important role in some of these objects as well.
Moreover, VLBI observations of nearby low-luminosity AGN reveal compact
flat-spectrum radio cores very similar to those in bright radio-loud blazars.
Furthermore, with the detection of X-ray emission from the least luminous AGN
we can study, Sgr A* in the Galactic Center, this source now seems to be
dominated entirely by non-thermal emission -- like in BL Lacs. The same may be
true for some X-ray binaries in the Low/Hard-state. Inclusion of low-power
radio jets into the overall picture of AGN provides some clues for what type of
accretion is important, what the power, radiative efficiency and matter-content
of jets is, and what mechanism could be responsible for making jets radio-loud.
We specifically discuss whether proton-proton collisions in a hot accretion
flow could provide the switch for the radio-dichotomy.

</DOC>
<DOC>
<DOCNO> 68214 </DOCNO>
The masses of the mesons and baryons. Part I. The Integer Multiple Rule


  From the well-known decays of the particles follows that the mesons and
baryons consist of a $\gamma$-branch and a neutrino branch. From the well-known
masses of the particles follows that the masses of the $\gamma$-branch
particles are integer multiples of the mass of the $\pi^0$ meson, within 3%, in
spite of differences in spin, isospin, strangeness and charm. The average
factor in front of the integer multiples of $m(\pi^0)$ of the $\gamma$-branch
particles is $1.0073 \pm 0.0184$. The masses of the $\nu$-branch particles are
integer multiples of the mass of the $\pi^\pm$ mesons, times a factor $0.86 \pm
0.02$. The existence of the integer multiple rule can be verified from the
Particle Physics Summary using a calculator.

</DOC>
<DOC>
<DOCNO> 120651 </DOCNO>
Interpreting the optical data of the Hubble Deep Field South: colors,


  We present an analysis of the optical data of the Hubble Deep Field South. We
derive F300W(AB), F450W(AB), F606W(AB) and F814W(AB) number counts for galaxies
in all four bands. The slope is steeper at shortest wavelengths: we estimated
gamma(F300W(AB))=0.47, gamma(F450W(AB))=0.35, gamma(F606W(AB))=0.28 and
gamma(F814W(AB))=0.28. Morphological number counts are actually dominated by
late type galaxies, while early type galaxies show a decreasing slope at faint
magnitudes. Combining this information with photometric redshifts, we notice
that galaxies contributing with a steep slope to morphological number counts
(i.e. spiral and irregular galaxies) have z>1, suggesting a moderate merging.
However we emphasize that any cut in apparent magnitude at optical wavelengths
results in samples biased against elliptical galaxies, affecting as a
consequence the redshift distributions and the implications on the evolution of
galaxies along the Hubble sequence.

</DOC>
<DOC>
<DOCNO> 12176 </DOCNO>
Scaling behavior in a quantum wire with scatterers


  We study the conductance properties of a straight two-dimensional quantum
wire with impurities modeled by $s$-like scatterers. Their presence can lead to
strong inter-channel coupling. It was shown that such systems depend
sensitively on the number of transverse modes included. Based on a poor man's
scaling technique we include the effect of higher modes in a renormalized
coupling constant. We therefore show that the low-energy behavior of the wire
is dominated by only a few modes, which hence is a way to reduce the necessary
computing power. The technique is successfully applied to the case of one and
two $s$-like scatterers.

</DOC>
<DOC>
<DOCNO> 102444 </DOCNO>
On the constants for some Sobolev imbeddings


  We consider the imbedding inequality || f ||_{L^r(R^d)} <= S_{r,n,d} || f
||_{H^{n}(R^d)}; H^{n}(R^d) is the Sobolev space (or Bessel potential space) of
L^2 type and (integer or fractional) order n. We write down upper bounds for
the constants S_{r, n, d}, using an argument previously applied in the
literature in particular cases. We prove that the upper bounds computed in this
way are in fact the sharp constants if (r=2 or) n > d/2, r=infinity, and
exhibit the maximising functions. Furthermore, using convenient trial
functions, we derive lower bounds on S_{r,n,d} for n > d/2, 2 < r < infinity;
in many cases these are close to the previous upper bounds, as illustrated by a
number of examples, thus characterizing the sharp constants with little
uncertainty.

</DOC>
<DOC>
<DOCNO> 11157 </DOCNO>
Out of Equilibrium Dynamics of the Hopfield Model in its spin-glass


  In this work we study numerically the out of equilibrium dynamics of the
Hopfield model for associative memory inside its spin-glass phase. Besides its
interest as a neural network model it can also be considered as a prototype of
fully connected magnetic systems with randomness and frustration. By adjusting
the ratio between the number of stored configurations $p$ and the total number
of neurons $N$ one can control the phase-space structure, whose complexity can
vary between the simple mean-field ferromagnet (when $p=1$) and that of the
Sherrington-Kirkpatrick spin-glass model (for a properly taken limit of an
infinite number of patterns). In particular, little attention has been devoted
to the spin-glass phase of this model. In this work we analyse the two-time
auto-correlation function, the decay of the magnetization and the distribution
of overlaps between states. The results show that within the spin-glass phase
of the model the dynamics exhibits ageing phenomena and presents features that
suggest a non trivial breaking of replica symmetry.

</DOC>
<DOC>
<DOCNO> 12637 </DOCNO>
Modeling of diffusion processes on physical and structural levels of


  A possibility to use an integral operator for establishing the link between
physical and structural levels of materials in modeling diffusion processes is
considered. We show how to perform the transition from the stochastic
description of motion of a system of points to the continuum description of
diffusive profiles.

</DOC>
<DOC>
<DOCNO> 84771 </DOCNO>
Measurement of Newton's Constant Using a Torsion Balance with Angular


  We measured Newton's gravitational constant G using a new torsion balance
method. Our technique greatly reduces several sources of uncertainty compared
to previous measurements: (1) it is insensitive to anelastic torsion fiber
properties; (2) a flat plate pendulum minimizes the sensitivity due to the
pendulum density distribution; (3) continuous attractor rotation reduces
background noise. We obtain G = (6.674215 +- 0.000092)x10^-11 m^3kg^-1s^-2; the
Earth's mass is, therefore, M = (5.972245 +- 0.000082)x10^24 kg and the Sun's
mass is M = (1.988435 +- 0.000027)x10^30kg.

</DOC>
<DOC>
<DOCNO> 122981 </DOCNO>
The nuclear cusp slopes of dwarf elliptical galaxies


  We derive the light profiles for a sample of 25 dwarf elliptical galaxies
observed by us with HST/WFPC2 in F555W and F814W. These profiles are fitted
with Nuker, R^1/4, exponential, and Sersic laws, and are also used to derive
the nuclear cusp slopes gamma. We discuss the correlation of nuclear cusp slope
with galactic luminosity, presence of a nucleus, and type of light profile. The
results are compared to those found in the literature for elliptical galaxies
and the bulges of spiral galaxies. We find that as a class the nuclear regions
of dwarf ellipticals are very similar to those of the exponential bulges of
spiral galaxies, and have nuclear cusp slopes shallower than those of bulges
that were well fitted by a de Vaucouleurs R^1/4 profile with the same
luminosity. For the 14 nucleated galaxies in our sample this conclusion is less
certain than for the 11 non-nucleated objects since it relies on an
extrapolation of galaxy light under the nucleus. In terms of their light
profiles and nuclear properties, most spheroidal stellar systems can be broadly
divided into two subclasses: the exponential shallow cusp objects and the
R^1/4, steep cusp objects. Membership of a class does not appear to correlate
with the presence of a massive stellar disk.

</DOC>
<DOC>
<DOCNO> 100720 </DOCNO>
Geometry on arc spaces of algebraic varieties


  This paper is a survey on arc spaces, a recent topic in algebraic geometry
and singularity theory. The geometry of the arc space of an algebraic variety
yields several new geometric invariants and brings new light to some classical
invariants.

</DOC>
<DOC>
<DOCNO> 122855 </DOCNO>
Implications of the PSR 1257+12 Planetary System for Isolated


  The first extrasolar planets were discovered in 1992 around the millisecond
pulsar PSR 1257+12. We show that recent developments in the study of accretion
onto magnetized stars, plus the existence of the innermost, moon-sized planet
in the PSR 1257+12 system, suggest that the pulsar was born with approximately
its current rotation frequency and magnetic moment. If so, this has important
implications for the formation and evolution of neutron star magnetic fields as
well as for the formation of planets around pulsars. In particular, it suggests
that some and perhaps all isolated millisecond pulsars may have been born with
high spin rates and low magnetic fields instead of having been recycled by
accretion.

</DOC>
<DOC>
<DOCNO> 119939 </DOCNO>
Simulations of Observations with the Optical Monitor of the X-Ray


  This paper addresses the question of the observations to be performed with
the Optical Monitor (OM) of the X-ray Multi-Mirror Satellite (XMM) under
several aspects. First, we discuss XMM-OM's photometric system and its colour
transformations towards the standard UBV system. Second, we establish a set of
procedures to determine the temperature and the amount of interstellar
absorption affecting the observed stars. Last, we address the possibility of
isolating quasars in multidimensional colour diagrams based on the XMM-OM
filter set.

</DOC>
<DOC>
<DOCNO> 152175 </DOCNO>
Fundamental Strings in Open String Theory at the Tachyonic Vacuum


  We show that the world-volume theory on a D-p-brane at the tachyonic vacuum
has solitonic string solutions whose dynamics is governed by the Nambu-Goto
action of a string moving in (25+1) dimensional space-time. This provides
strong evidence for the conjecture that at this vacuum the full (25+1)
dimensional Poincare invariance is restored. We also use this result to argue
that the open string field theory at the tachyonic vacuum must contain closed
string excitations.

</DOC>
<DOC>
<DOCNO> 100078 </DOCNO>
Dynamical quantum groups at roots of 1


  Given a dynamical twist for a finite dimensional Hopf algebra we construct
two weak Hopf algebras, using methods of Xu and Etingof-Varchenko, and show
that they are dual to each other. We generalize the theory of dynamical quantum
groups to the case when the quantum parameter q is a root of unity. These
objects turn out to be self-dual -- which is a fundamentally new property, not
satisfied by the usual Drinfeld-Jimbo quantum groups.

</DOC>
<DOC>
<DOCNO> 13513 </DOCNO>
Comment on: "Phenomenological model of Dynamic Nonlinear Response in


  In a recent paper (A.E. Glazounov and A.K. Tagantsev, Phys.Rev. Lett. 85,
2192 (2000)) it has been proposed a phenomenological model of the dynamic
non-linear response in relaxor ferroelectrics based on the averaging of the
Landau-Khalatnikov equation over the distribution of the relaxation times. The
purpose of the present comment is to clarify the physical assumptions involved
in the Glazounov-Tagantsev approach and show that models based on the
Landau-Khalatnikov equation can not describe properly the dynamic response in
relaxor ferroelectrics.

</DOC>
<DOC>
<DOCNO> 116571 </DOCNO>
On the Indication from Pioneer 10/11 Data of an Apparent Anomalous,


  It is discussed how the anomalous acceleration shed additional light on the
dynamic feature of expanding universe.

</DOC>
<DOC>
<DOCNO> 68797 </DOCNO>
Four-quark state in QCD


  The spectra of some 0++ four-quark states, which are composed of \bar qq
pairs, are calculated in QCD. The light four-quark states are calculated using
the traditional sum rules while four-quark states containing one heavy quark
are computed in HQET. For constructing the interpolating currents, different
couplings of the color and spin inside the \bar qq pair are taken into account.
It is found that the spin and color combination has little effect on the mass
of the four-quark states.

</DOC>
<DOC>
<DOCNO> 72105 </DOCNO>
The role of supersymmetry phenomenology in particle physics


  Supersymmetry phenomenology is an important component of particle physics
today. I provide a definition of supersymmetry phenomenology, outline the scope
of its activity, and argue its legitimacy. This essay derives from a
presentation given at the 2000 SLAC Summer Institute.

</DOC>
<DOC>
<DOCNO> 69434 </DOCNO>
Steep inflation: ending braneworld inflation by gravitational particle


  We propose a scenario for inflation based upon the braneworld picture, in
which high-energy corrections to the Friedmann equation permit inflation to
take place with potentials ordinarily too steep to sustain it. Inflation ends
when the braneworld corrections begin to lose their dominance. Reheating may
naturally be brought about via gravitational particle production, rather than
the usual inflaton decay mechanism; the reheat temperature may be low enough to
satisfy the gravitino bound and the Universe becomes radiation dominated early
enough for nucleosynthesis. We illustrate the idea by considering steep
exponential potentials, and show they can give satisfactory density
perturbations (both amplitude and slope) and reheat successfully. The scalar
field may survive to the present epoch without violating observational bounds,
and could be invoked in the quintessential inflation scenario of Peebles and
Vilenkin.

</DOC>
<DOC>
<DOCNO> 13279 </DOCNO>
Magnetic Polarons and the Metal-Semiconductor Transition in (Eu,La)B6


  We present inelastic light scattering measurements of EuO and
Eu$_{1-x}$La$_{x}$B$_6$ ($x$=0, 0.005, 0.01, 0.03, and 0.05) as functions of
doping, B isotope, magnetic field, and temperature. Our results reveal a
variety of distinct regimes as a function of decreasing T: (a) a paramagnetic
semimetal regime, which is characterized by a collision-dominated electronic
scattering response whose scattering rate $\Gamma$ decreases with decreasing
temperature; (b) a spin-disorder scattering regime, which is characterized by a
collision-dominated electronic scattering response whose scattering rate
$\Gamma$ scales with the magnetic susceptibility; (c) a magnetic polaron (MP)
regime, in which the development of an $H$=0 spin-flip Raman response betrays
the formation of magnetic polarons in a narrow temperature range above the
Curie temperature T$_{\rm C}$; and (d) a ferromagnetic metal regime,
characterized by a flat electronic continuum response typical of other strongly
correlated metals. By exploring the behavior of the Raman responses in these
various regimes in response to changing external parameters, we are able to
investigate the evolution of charge and spin degrees of freedom through various
transitions in these materials.

</DOC>
<DOC>
<DOCNO> 11521 </DOCNO>
Spectral functions in a magnetic field as a probe of spin-charge


  We show that the single-particle spectral functions in a magnetic field can
be used to probe spin-charge separation of a Luttinger liquid. Away from the
Fermi momentum, the magnetic field splits both the spinon peak and holon peak;
here the spin-charge separation nature is reflected in the different magnitude
of the two splittings. At the Fermi momentum, the magnetic field splits the
zero-field peak into four. The feasibility of studying this effect using
angle-resolved photoemission and momentum-resolved tunneling is discussed.

</DOC>
<DOC>
<DOCNO> 84861 </DOCNO>
Clumps into Voids


  We consider a spherically symmetric distribution of dust and show that it is
possible, under general physically reasonable conditions, for an overdensity to
evolve to an underdensity (and vice versa). We find the conditions under which
this occurs and illustrate it on a class of regular Lemaitre-Tolman-Bondi
solutions. The existence of this phenomenon, if verified, would have the result
that the topology of density contours, assumed fixed in standard structure
formation theories, would have to change and that luminous matter would not
trace the dark matter distribution so well.

</DOC>
<DOC>
<DOCNO> 99566 </DOCNO>
Deformation quantization with traces


  In the present paper we prove a statement closely related to the cyclic
formality conjecture. In particular, we prove that for a divergence-free
Poisson bivector field on R^d, the Kontsevich star-product with the harmonic
angle function is cyclic. We also prove a globalization of this theorem in the
case of arbitrary Poisson manifolds and prove a generalization of the
Connes-Flato-Sternheimer conjecture on closed star-products in the Poisson
case.

</DOC>
<DOC>
<DOCNO> 69467 </DOCNO>
Radiation of single photons from $Pb+Pb$ collisions at the CERN SPS and


  The production of single photons in $Pb+Pb$ collisions at the CERN SPS as
measured by the WA98 experiment is analysed. A quark gluon plasma is assumed to
be formed initially, which expands, cools, hadronizes, and undergoes
freeze-out. A rich hadronic equation of state is used and the transverse
expansion of the interacting system is taken into account. The recent estimates
of photon production in quark-matter (at two loop level) along with the
dominant reactions in the hadronic matter leading to photons are used. About
50% of the single photons are seen to have a thermal origin. An addition of the
thermal and prompt photons is seen to provide a very good description of the
data. Most of the thermal photons having large transverse momenta arise from
the quark-matter, which contributes dominantly through the mechanism of
annihilation of quarks with scattering, and which in turn is possible only in a
hot and dense plasma of quarks and gluons. The results thus confirm the
formation of quark gluon plasma and the existence of this mechanism of the
production of single photons.

</DOC>
<DOC>
<DOCNO> 120558 </DOCNO>
The Outbursts of Dwarf Novae


  We present a numerical scheme for the evolution of an accretion disc through
a dwarf nova outburst. We introduce a time-varying artificial viscosity into an
existing smoothed particle hydrodynamics code optimised for two and
three-dimensional simulations of accretion discs. The technique gives rise to
coherent outbursts and can easily be adapted to include a complete treatment of
thermodynamics. We apply a two-dimensional isothermal scheme to the system SS
Cygni and present a wide range of observationally testable results.

</DOC>
<DOC>
<DOCNO> 102579 </DOCNO>
Noncommutative tori and universal sets of non-binary quantum gates


  Problem of universality in simulation of evolution of quantum system and in
theory of quantum computations related with possibility of expression or
approximation of arbitrary unitary transformation by composition of specific
unitary transformations (quantum gates) from given set. In earlier paper
(quant-ph/0010071) was shown application of Clifford algebras to constructions
of universal sets of binary quantum gates $U_k \in U(2^n)$. For application of
similar approach to non-binary quantum gates $U_k \in U(l^n)$ in present work
is used rational noncommutative torus ${\Bbb T}^{2n}_{1/l}$. Set of universal
non-binary two-gates is presented here as one of examples.

</DOC>
<DOC>
<DOCNO> 12780 </DOCNO>
Interlayer coupling and the c-axis quasiparticle transport in


  The c-axis quasiparticle conductivity shows different behavior depending on
the nature of the interlayer coupling. For coherent coupling with a constant
hopping amplitude $t_{\perp}$, the conductivity at zero frequency and zero
temperature $\sigma(0,0)$ depends on the direction of the magnetic field, but
it does not for angle-dependent hopping $t(\phi)$ which removes the
contribution of the nodal quasiparticles. For incoherent coupling, the
conductivity is also independent of field direction and changes only when
paramagnetic effects are included. The conductivity sum rule can be used to
determine the admixture of coherent to incoherent coupling. The value of
$\sigma(0,0)$ can be dominated by $t_{\perp}$ while at the same time $t(\phi)$
dominates the temperature dependence of the superfluid density.

</DOC>
<DOC>
<DOCNO> 99473 </DOCNO>
BFV-BRST analysis of equivalence between noncommutative and ordinary


  Constrained hamiltonian structure of noncommutative gauge theory for the
gauge group U(1) is discussed. Constraints are shown to be first class,
although, they do not give an Abelian algebra in terms of Poisson brackets. The
related BFV-BRST charge gives a vanishing generalized Poisson bracket by itself
due to the associativity of *-product. Equivalence of noncommutative and
ordinary gauge theories is formulated in generalized phase space by using
BFV-BRST charge and a solution is obtained. Gauge fixing is discussed.

</DOC>
<DOC>
<DOCNO> 99953 </DOCNO>
Lieb-Thirring Inequalities


  This is a brief review of Lieb-Thirring inequalities for eigenvalues of the
Schroedinger operator and lower bounds for the quantum mechanical kinetic
energy (and some generalizations) in R^n.

</DOC>
<DOC>
<DOCNO> 11105 </DOCNO>
Substrate Sensitivity of the Adhesion and Material Properties of


  Hydrogenated amorphous carbon (a-C:H), deposited by the rf-plasma enhanced
chemical vapour deposition (rf-PECVD) technique, is a promising material for
large area electronic and interlayer dielectric applications. The structural
and electronic properties of rf-PECVD a-C:H, deposited at room temperature from
CH4/He and CH4/Ar gas mixtures, are shown to be sensitive to the substrate on
which the thin film is deposited. The choice of substrate (c-Si or C7059
glass), and the existence and geometrical dimensions of any metallic pattern on
the substrate surface, can result in significant spatial variations in the
a-C:H adhesion and material properties. The observed effects are attributed to
potential variations across the metal patterned substrates which influence the
'local' dc self-bias. This leads to spatial variations in the growth conditions
and hence material properties. For electronic device and dielectric isolation
applications this effect can result in significant variations in operating
performance. The nature of the substrate and any overlying metallisation
pattern are therefore important considerations.

</DOC>
<DOC>
<DOCNO> 121317 </DOCNO>
Baryonic Tully-Fisher Relations


  I describe the disk mass-rotation velocity relation which underpins the
familiar luminosity-linewidth relation. Continuity of this relation favors
nearly maximal stellar mass-to-light ratios. This contradicts the low
mass-to-light ratios implied by the lack of surface brightness dependence in
the same relation.

</DOC>
<DOC>
<DOCNO> 10576 </DOCNO>
The growth dynamics of German business firms


  We determine the distribution of size and growthrates of German business
firms in 1987-1997. We find a log-normal size distribution. The distribution of
growth rates has fat tails. It can be fitted to an exponential in a narrow
central region and is dominated by finite-sample-size effects far in its wings.
We study the dependence of the growth rate distribution on firm size: depending
on procedures, we find almost no dependence when the center of the distribution
is considered or, similar to previous work, a power-law when the wings are
weighted more strongly. Correlations in the growth of different firms are
essentially random. We determine the annual growth of the entire economy, and
successfully correlate it with a standard economic indicator of business cycles
in Germany. We emphasize possible problems related to the finite number of
firms comprised in our database and its short extension in time.

</DOC>
<DOC>
<DOCNO> 83113 </DOCNO>
Extending Classical Logic with Inductive Definitions


  The goal of this paper is to extend classical logic with a generalized notion
of inductive definition supporting positive and negative induction, to
investigate the properties of this logic, its relationships to other logics in
the area of non-monotonic reasoning, logic programming and deductive databases,
and to show its application for knowledge representation by giving a typology
of definitional knowledge.

</DOC>
<DOC>
<DOCNO> 70706 </DOCNO>
Bottom and Charm Production at LHC and RHIC


  We study $b\bar{b}$ and $c\bar{c}$ production and the influence of nuclear
shadowing at LHC and RHIC energies. We find a significant reduction in the
production cross section of both charm and bottom at RHIC and LHC. Bound states
such as $\Upsilon$ and $J/\Psi$ are suppressed by this reduction in the charm
production cross sections. Therefore, $J/\Psi$ suppression may not be useful as
a signature for the quark gluon plasma.

</DOC>
<DOC>
<DOCNO> 121482 </DOCNO>
Halpha emitting galaxies and the cosmic star formation rate at z = 2.2


  About 10 candidate Halpha emitting galaxies at z = 2.2 have been detected in
a 2.1 um narrow band imaging survey covering an area of 100 sq. arcmin
including the WFPC2 and STIS fields in the Hubble Deep Field South. Six of
these have subsequently been confirmed spectroscopically using ISAAC at the ESO
VLT. Star formation rates of the individual galaxies derived from their Halpha
fluxes are 20-35 Msolar/yr, without any correction for extinction, whereas SFRs
derived from their rest frame UV continuum fluxes are up to a factor of 4 lower
- consistent with lower extinction to Halpha. Velocity dispersions are
typically ~ 100km/s and one galaxy, observed under the most favorable
conditions, shows a rotation curve with a terminal velocity ~ 140 km/s at ~
3kpc radius which is within the range observed for nearby spiral galaxies.
These thus appear to be relatively massive systems at high redshift. Comparison
with the HST NICMOS grism Halpha survey of Yan et al. (1999) reveals little or
no evolution in the Halpha luminosity function between z ~ 1.3 and 2.2. The
inferred star formation rate density of 0.12 Msolar/Mpc^3/yr at z = 2.2 is also
equal to that at z ~ 3-4.5 derived by Steidel et al.(1999) from extinction
corrected UV continuum fluxes.

</DOC>
<DOC>
<DOCNO> 151804 </DOCNO>
Global geometric properties of AdS space and the AdS/CFT correspondence


  The Poisson kernels and relations between them for a massive scalar field in
a unit ball $B^n$ with Hua's metric and conformal flat metric are obtained by
describing the $B^n$ as a submanifold of an $(n+1)$-dimensional embedding
space. Global geometric properties of the AdS space are discussed. We show that
the $(n+1)$-dimensional AdS space AdS$_{n+1}$ is isomorphic to $RP^1\times B^n$
and boundary of the AdS is isomorphic to $RP^1\times S^{n-1}$. Bulk-boundary
propagator and the AdS/CFT like correspondence are demonstrated based on these
global geometric properties of the $RP^1\times B^n$.

</DOC>
<DOC>
<DOCNO> 117053 </DOCNO>
Alarming Oxygen Depletion Caused by Hydrogen Combustion and Fuel Cells


  We recall that hydrogen combustion does resolve the environmental problems of
fossil fuels due to excessive emission of carcinogenic substances and carbon
dioxide. However, hydrogen combustion implies the permanent removal from our
atmosphere of directly usable oxygen, a serious environmental problem called
oxygen depletion, since the combustion turns oxygen into water whose separation
to restore the original oxygen is prohibitive due to cost. We then show that a
conceivable global use of hydrogen in complete replacement of fossil fuels
would imply the permanent removal from our atmosphere of 2.8875x10^7 metric
tons O_2/day. Fuel cells are briefly discussed to point out similarly serious
environmental problems, again, for large uses. We propose the possibility of
resolving these problems by upgrading hydrogen to the new combustible fuel
called magnegas^TM, whose chemical structure is composed by the new chemical
species of magnecules, whose energy content and other features are beyond the
descriptive capacities of quantum chemistry. In fact, magnegas contains up to
50% hydrogen, while having combustion exhaust with: 1) a positive oxygen
balance (releasing more oxygen in the exhaust than that used in the
combustion); 2) no appreciable carcinogenic or toxic substances; 3)
considerably reduced carbon dioxide as compared to fossil fuels; 4)
considerably reduced nitrogen oxides; and 5) general reduction of pollutants in
the exhaust up to 96% of current EPA standards.

</DOC>
<DOC>
<DOCNO> 120332 </DOCNO>
The ASCA Hard Serendipitous Survey


  We summarize here some of the main results we have reached so far in the ASCA
Hard Serendipitous Survey, a survey program conducted in the 2-10 keV energy
band. In particular we will discuss the number-flux relationship, the 2-10 keV
spectral properties of the sources, and the cross-correlation of the ASCA
sources with ROSAT sources.

</DOC>
<DOC>
<DOCNO> 99853 </DOCNO>
Branched cyclic covers and finite type invariants


  This work identifies a class of moves on knots which translate to
$m$-equivalences of the associated $p$-fold branched cyclic covers, for a fixed
$m$ and any $p$ (with respect to the Goussarov-Habiro filtration.) These moves
are applied to give a flexible (if specialised) construction of knots for which
the Casson-Walker-Lescop invariant (for example) of their $p$-fold branched
cyclic covers may be readily calculated, for any choice of $p$. In the second
part of this paper, these operations are illustrated by some theorems
concerning the relationship of knot invariants obtained from finite type
three-manifold invariants, via the branched cyclic covering construction, with
the finite type theory of knots.

</DOC>
<DOC>
<DOCNO> 118891 </DOCNO>
Wide-field J- and K-band galaxy counts in the ELAIS fields


  New near-infrared galaxy counts in the J and K bands are presented over a
total area of 0.70 and 0.97 degrees^2, respectively. The limiting magnitudes of
the deepest regions are 19.5 in J and 18.0 in K. At J>16 and K>15 our J and
K-band counts number counts agree well with existing surveys provided all data
are corrected to a common magnitude scale. There are real differences from
field to field, and the ELAIS N1 and N2 fields show an overdensity of J<16,
K<15 galaxies. The slopes of log N(m) / dm are 0.40 to 0.45 at 15<K<18 and
16<J<19.5. Our counts favor galaxy models with a high normalization of the
local luminosity function and without strong evolution.

</DOC>
<DOC>
<DOCNO> 100752 </DOCNO>
On the Dynamics of Crystal Electrons, high Momentum Regime


  We study the quantum dynamics generated by $H^{SW}=-{d^2\over dx^2}+V-x$ with
$V$ a real periodic function of weak regularity. We prove that the continuous
spectrum of $H^{SW}$ is never empty, and furthermore that for $V$ small enough
there are no bound states.

</DOC>
<DOC>
<DOCNO> 7966 </DOCNO>
Models for Free Granular Surfaces


  We introduce two sets of continuum equations to describe granular flow on a
free surface and study their properties. The equations derived from a
microscopic picture that includes jumps and a mobility threshold, account for
ripple and crater formation.

</DOC>
<DOC>
<DOCNO> 99843 </DOCNO>
Zeta functions and 'Kontsevich invariants' on singular varieties


  Let X be a nonsingular algebraic variety in characteristic zero. To an
effective divisor on X Kontsevich has associated a certain 'motivic integral',
living in a completion of the Grothendieck ring of algebraic varieties. He used
this invariant to show that birational Calabi-Yau varieties have the same Hodge
numbers. Then Denef and Loeser introduced the motivic (Igusa) zeta function,
associated to a regular function on X, which specializes to both the classical
p-adic Igusa zeta function and the topological zeta function, and also to
Kontsevich's invariant.
  This paper treats a generalization to singular varieties. Batyrev already
considered such a 'Kontsevich invariant' for log terminal varieties (on the
level of Hodge polynomials instead of in the Grothendieck ring), and previously
we introduced a motivic zeta function on normal surface germs. Here on any
Q-Gorenstein variety X we associate a motivic zeta function and a 'Kontsevich
invariant' to effective Q-Cartier divisors on X whose support contains the
singular locus of X.

</DOC>
<DOC>
<DOCNO> 101300 </DOCNO>
Twist of Lie algebras by 6 dimensional subalgebra


  A new non-standard deformation of all types of classical Lie algebras is
constructed by means of Drinfel'd twist based on a six dimensional subalgebra.
This is an extension of extended twists introduced by Kulish et al. For the
algebra M_3 = so(3,2), a relation to a known non-standard deformation is
discussed.

</DOC>
<DOC>
<DOCNO> 151164 </DOCNO>
Matrix Strings in Weakly Curved Background Fields


  We investigate further the recent proposal for the form of the Matrix theory
action in weak background fields. We perform DVV reduction to the multiple
D0-brane action in order to find the Matrix string theory action for multiple
fundamental strings in curved but weak NS-NS and R-R backgrounds. This matrix
sigma model gives a definite prescription on how to deal with R-R fields with
an explicit spacetime dependence in Type II string theory. We do this both via
the 9-11 flip and the chain of T and S dualities, and further check on their
equivalence explicitly. In order to do so, we also discuss the implementation
of S-duality in the operators of the 2-dimensional world-volume supersymmetric
gauge theory describing the Type IIB D-string. We compare the result to the
known Green-Schwarz sigma model action (for one string), and use this
comparison in order to discuss about possible, non-linear background curvature
corrections to the Matrix string action (involving many strings), and therefore
to the Matrix theory action. We illustrate the nonabelian character of our
action with an example involving multiple fundamental strings in a non-trivial
R-R flux, where the strings are polarized into a noncommutative configuration.
This corresponds to a dielectric type of effect on fundamental strings.

</DOC>
<DOC>
<DOCNO> 121738 </DOCNO>
Automatic Shell Detection in CGPS Data


  A numerical code aiming at the automatic detection of spherical expanding HI
shells in radio data-cubes is presented. The following five shell parameters
are allowed to vary within a specified range: angular radius, expansion
velocity and three center coordinates (galactic coordinates l and b, and
systemic radial velocity V). We discuss several factors which can reduce the
sensitivity of the shell detection: the presence of noise (both instrumental
and "structural"), the fragmentation and asphericity of the shell and the
inhomogeneity of the background and/or foreground emission. The code is tested
on four objects: two HII regions and two early B stars. We use HI data from the
Canadian Galactic Plane Survey. In all four cases the evidence for an expanding
HI shell is found.

</DOC>
<DOC>
<DOCNO> 169673 </DOCNO>
Quantum Field Symbolic Analog Computation: Relativity Model


  It is natural to consider a quantum system in the continuum limit of
space-time configuration. Incorporating also, Einstein's special relativity,
leads to the quantum theory of fields. Non-relativistic quantum mechanics and
classical mechanics are special cases. By studying vacuum expectation values
(Wightman functions W(n; z) where z denotes the set of n complex variables) of
products of quantum field operators in a separable Hilbert space, one is led to
computation of holomorphy domains for these functions over the space of several
complex variables, C^n. Quantum fields were reconstructed from these functions
by Wightman. Computer automation has been accomplished as deterministic exact
analog computation (computation over "cells" in the continuum of C^n) for
obtaining primitive extended tube domains of holomorphy. This is done in a one
dimensional space plus one dimensional time model. By considering boundary
related semi-algebraic sets, some analytic extensions of these domains are
obtained by non-deterministic methods. The novel methods of computation raise
interesting issues of computability and complexity. Moreover, the computation
is independent of any particular form of Lagrangian or dynamics, and is uniform
in n, qualifying for a universal quantum machine over C^infinity.

</DOC>
<DOC>
<DOCNO> 100232 </DOCNO>
Quantum ergodicity for Pauli Hamiltonians with spin 1/2


  Quantum ergodicity, which expresses the semiclassical convergence of almost
all expectation values of observables in eigenstates of the quantum Hamiltonian
to the corresponding classical microcanonical average, is proven for
non-relativistic quantum particles with spin 1/2. It is shown that quantum
ergodicity holds, if a suitable combination of the classical translational
dynamics and the spin dynamics along the trajectories of the translational
motion is ergodic.

</DOC>
<DOC>
<DOCNO> 12001 </DOCNO>
Distance-depending electron-phonon interactions from one- and two-body


  For a dimer with a non-degenerate orbital built from atomic wave functions of
Gaussian shape we evaluate all the electron-phonon couplings derived from the
one-body and two-body electronic interactions, considering both the adiabatic
and extreme non-adiabatic limit. Not only the values of the coupling parameters
in the two limits, but also the expressions of the corresponding terms in the
Hamiltonian differ.
 Depending on the distance between the dimer ions, some of the two-body
couplings are comparable, or even larger than the one-body ones.

</DOC>
<DOC>
<DOCNO> 151382 </DOCNO>
Quantization conditions from the group theory


  We show that the requirement of the relativistic invariance for any
self-interacting, abelian p-form theory uniquely determines the form of the
corresponding quantization condition.

</DOC>
<DOC>
<DOCNO> 12092 </DOCNO>
Modeling the series of (n x 2) Si-rich reconstructions of beta-SiC(001):


  We perform ab initio plane wave supercell density functional calculations on
three candidate models of the (3 x 2) reconstruction of the beta-SiC(001)
surface. We find that the two-adlayer asymmetric-dimer model (TAADM) is
unambiguously favored for all reasonable values of Si chemical potential. We
then use structures derived from the TAADM parent to model the silicon lines
that are observed when the (3 x 2) reconstruction is annealed (the (n x 2)
series of reconstructions), using a tight-binding method. We find that as we
increase n, and so separate the lines, a structural transition occurs in which
the top addimer of the line flattens. We also find that associated with the
separation of the lines is a large decrease in the HOMO-LUMO gap, and that the
HOMO state becomes quasi-one-dimensional. These properties are qualititatively
and quantitatively different from the electronic properties of the original (3
x 2) reconstruction.

</DOC>
<DOC>
<DOCNO> 170444 </DOCNO>
Non-Interacting Fermions in a One-Dimensional Harmonic Atom Trap: Exact


  One-particle properties of non-interacting Fermions in a one-dimensional
harmonic trap and at zero temperature are studied. Exact expressions and
asymptotic results for large Fermion number N are given for the particle
density distribution n_0(z,N). For large N and near the classical boundary at
the Fermi energy the density displays increasing fluctuations. A simple scaling
of these tails of the density distribution with respect to N is established.
The Fourier transform of the density distribution is calculated exactly. It
displays a small but characteristic hump near 2 k_F with k_F being a properly
defined Fermi wave number. This is due to Friedel oscillations which are
identified and discussed. These quantum effects are missing in the
semi-classical approximation. Momentum distributions are also evaluated and
discussed. As an example of a time-dependent one-particle problem we calculate
exactly the evolution of the particle density when the trap is suddenly
switched off and find a simple scaling behaviour in agreement with recent
general results.

</DOC>
<DOC>
<DOCNO> 13728 </DOCNO>
Bifurcation in kinetic equation for interacting Fermi systems


  The finite duration of collisions appear as time-nonlocality in the kinetic
equation. Analyzing the corresponding quantum kinetic equation for dense
interacting Fermi systems a delay differential equation is obtained which
combines time derivatives with finite time stepping known from the logistic
mapping. The responsible delay time is explicitly calculated and discussed. As
a novel feature oscillations in the time evolution of the distribution function
itself appear and bifurcations up to chaotic behavior can occur. The
temperature and density conditions are presented where such oscillations and
bifurcations arise indicating an onset of phase transition.

</DOC>
<DOC>
<DOCNO> 151788 </DOCNO>
F(4) Supergravity and 5D Superconformal Field Theories


  We give a short account of the recently constructed N=2 D=6 matter coupled
supergravity based on the F(4) exceptional supergroup and of its 5D
superconformal theory correspondent.

</DOC>
<DOC>
<DOCNO> 123022 </DOCNO>
Temperature Structure of Four Merging Clusters Obtained with Chandra


  We present preliminary Chandra results on z=0.2 clusters A665, A2163 and
A2218, and a z=0.05 cluster A754. For A754, A665 and A2163, we have derived
first high-resolution projected gas temperature maps. All three show strong
spatial temperature variations in the inner r<0.5-1 Mpc regions, indicating
ongoing mergers. The maps reveal a probable shock in front of a moving cluster
core in A665, a rather complicated temperature distribution in the center of
A2163, and possibly a merger of three subclusters in A754. At greater
off-center distances, radial profiles for A2163 and A2218 show a temperature
decline, in agreement with earlier ASCA results.

</DOC>
<DOC>
<DOCNO> 68973 </DOCNO>
A new method for extracting the bottom quark Yukawa coupling at the CERN


  We propose a new method for measuring the H -> bb rate at the CERN LHC in a
manner which would allow extraction of the b quark Yukawa coupling. Higgs boson
production in purely electroweak WHjj events is calculated. The Standard Model
signal rate including decays W -> l nu and H -> bb is 11 fb for M_H = 120 GeV.
It is possible to suppress the principal backgrounds, Wbbjj and ttjj, to
approximately the level of the signal. As the top quark Yukawa coupling does
not appear in this process, it promises a reliable extraction of g_Hbb in the
context of the Standard Model or some extensions, such as the MSSM.

</DOC>
<DOC>
<DOCNO> 178400 </DOCNO>
From bound states to resonances: analytic continuation of the wave


  Single-particle resonance parameters and wave functions in spherical and
deformed nuclei are determined through analytic continuation in the potential
strength. In this method, the analyticity of the eigenvalues and eigenfunctions
of the Schroedinger equation with respect to the coupling strength is exploited
to analytically continue the bound-state solutions into the positive-energy
region by means of Pade' approximants of the second kind. The method is here
applied to single-particle wave functions of the $^{154}Sm$ and $^{131}Eu$
nuclei. A comparison of the results with the direct solution of the
Schroedinger equation shows that the method can be confidently applied also in
coupled-channel situations requiring high numerical accuracy.

</DOC>
<DOC>
<DOCNO> 121209 </DOCNO>
Polarization Signal of Distant Clusters and Reconstruction of Primordial


  We examine the polarization signal of the cosmic microwave background
radiation associated with distant clusters.
 The polarization is induced by the Thomson scattering of microwave photons
with ionized gas of clusters and contains information of quadrupole temperature
anisotropies observed at the clusters. The three-dimensional map of the signal
are expressed in terms of the spin-weighted harmonics for its angular
dependence. Its radial dependence is expanded perturbatively with respect to
the distances (equivalently redshifts) to the clusters.
 The independent information that we can extract out from the map is clarified
explicitly.

</DOC>
<DOC>
<DOCNO> 122810 </DOCNO>
Shock geometry and inverse Compton emission from the wind of a binary


  PSR B1259-63 is a 47ms radio pulsar with a high spin-down luminosity which is
in a close, highly eccentric 3.5-year orbit about a bright stellar companion.
The binary system may be a detectable source of hard gamma-rays produced by
inverse Compton scattering of photons from the B2e star SS2883 by electrons and
positrons in the pulsar wind. The star provides an enormous density of optical
photons in the vicinity of the pulsar, particularly at epochs near periastron.
We calculate the emission from the unshocked region of the pulsar wind,
assuming that it terminates at a shock where it attains pressure balance with
the companion's wind. The spectra and light curves for the inverse Compton
emission from the shock-terminated wind are compared with those for an
unterminated wind. If the pulsar's wind is weaker than that from the companion
star, the termination of the wind decreases the inverse Compton flux,
particularly near periastron. The termination shock geometry has the effect of
decreasing the asymmetry of the gamma-ray light curve around periastron, which
arises because of the asymmetrical variation of the scattering angle.

</DOC>
<DOC>
<DOCNO> 70757 </DOCNO>
Can Neutrinos and High-Energy Particles Test Finsler Metric of


  The Finsler-relativistic metric function $F(g;R)$ and the associated
Hamiltonian function $H(g;P)$, being considered together with explicit
Finslerian special-relativistic kinematic transformations, give rise to a
self-consistent and rigorous framework upon which corrections to
Lorentz-relativistic quantities can properly be evaluated. The concomitant
relations generalize their Lorentzian prototypes through the presence of a
single characteristic parameter, ~$g$, so that the explicated
Particle-Antiparticle Asymmetry, as well as the search for possible distinction
between the pseudo-Euclidean Light Geometry and the Finsler-relativistic
Neutrino Geometry, can well be traced in terms of this parameter. At any fixed
rest-mass value $m$ and $g\ne0$, the dependences of energy on three-dimensional
momentum prove to be of different forms, as given by the respective functions
$E^{(+)}(g;m;|{\bf P}|)$ and $E^{(-)}(g;m;|{\bf P}|)$, for particles and
antiparticles. This splitting of the mass-shell, as well as various entailed
Finslerian approximations with respect to $g$, can naturally be proposed for
experimental study in order to obtain estimations on $g$. Since neutrinos and
antineutrinos are uncomposed neat particles, measuring the difference between
their velocities seems to be the best way for testing implied Finslerian
corrections to conventional Lorentzian quantities. Accelerators which can
produce neutrinos and antineutrinos are ideal instruments to gain this aim. The
known measurements led to the conclusion that the difference $<0.7\cdot
10^{-4}~(95%~CL)$, while announced future long baseline neutrino experiments
probably raise the sensitivity to approach the high level of $\sim 10^{-9}$.

</DOC>
<DOC>
<DOCNO> 119590 </DOCNO>
The Case for an Accelerating Universe from Supernovae


  The unexpected faintness of high-redshift Type Ia supernovae (SNe Ia), as
measured by two teams, has been interpreted as evidence that the expansion of
the Universe is accelerating. We review the current challenges to this
interpretation and seek to answer whether the cosmological implications are
compelling. We discuss future observations of SNe Ia which could offer
extraordinary evidence to test acceleration.

</DOC>
<DOC>
<DOCNO> 84869 </DOCNO>
Origin of classical structure from inflation


  According to the inflationary scenario, all structure in the Universe can be
traced back to quantum fluctuations of the metric and scalar field(s) during
inflation. The seeds of this structure can be observed as classical
anisotropies in the cosmic microwave background. I briefly review how the
transition from the inherent quantum nature of these fluctuations to classical
behaviour comes about. Two features play a crucial role: Firstly, the quantum
state of the fluctuations becomes highly squeezed for wavelengths that exceed
the Hubble radius. Secondly, decoherence due to other fields distinguishes the
field-amplitude basis as the classical pointer basis. I also discuss the
entropy of the fluctuations and make a brief comparison with chaotic systems.

</DOC>
<DOC>
<DOCNO> 178438 </DOCNO>
Faddeev approach to confined three-quark problems


  We propose a method that allows for the efficient solution of the three-body
Faddeev equations in the presence of infinitely rising confinement
interactions. Such a method is useful in calculations of nonrelativistic and
especially semirelativistic constituent quark models. The convergence of the
partial wave series is accelerated and possible spurious contributions in the
Faddeev components are avoided. We demonstrate how the method works with the
example of the Goldstone-boson-exchange chiral quark model for baryons.

</DOC>
<DOC>
<DOCNO> 9955 </DOCNO>
Ageing of Natural Rubber under Stress


  We report a dynamical-mechanical study of stress relaxation at small
deformation in a natural (polyisoprene) rubber well above its glass transition
temperature Tg. We find that an almost complete relaxation of stress takes
place over very long periods of time, even though the elastic network integrity
is fully retained. The relaxation rate and the long-time equilibrium modulus
are sensitive functions of temperature which do not follow time-temperature
superposition. Many characteristic features of non-ergodic ageing response are
apparent at both short and very long times. We interpret the observed behaviour
in terms of the properties of rubber crosslinks, capable of isomerisation under
stress, and relate the results to recent models of soft glassy rheology.

</DOC>
<DOC>
<DOCNO> 80963 </DOCNO>
Fixed Point SU(3) Gauge Actions: Scaling Properties and Glueballs


  We present a new parametrization of a SU(3) fixed point (FP) gauge action
using smeared ("fat") gauge links. We report on the scaling behaviour of the FP
action on coarse lattices by means of the static quark-antiquark potential, the
hadronic scale $r_0$, the string tension $\sigma$ and the critical temperature
$T_c$ of the deconfining phase transition. In addition, we investigate the low
lying glueball masses where we observe no scaling violations within the
statistical errors.

</DOC>
<DOC>
<DOCNO> 102665 </DOCNO>
Propagation and interaction of shock waves of quasilinear equation


  We propose a new regularization method for constructing a shock wave type
solution with nonsmooth front (interaction of shock waves) for quasilinear
equations in the one-dimensional case.

</DOC>
<DOC>
<DOCNO> 101379 </DOCNO>
Representations of Cuntz algebras, loop groups and wavelets


  A theorem of Glimm states that representation theory of an NGCR C*-algebra is
always intractable, and the Cuntz algebra O_N is a case in point. The
equivalence classes of irreducible representations under unitary equivalence
cannot be captured with a Borel cross section. Nonetheless, we prove here that
wavelet representations correspond to equivalence classes of irreducible
representations of O_N, and they are effectively labeled by elements of the
loop group, i.e., the group of measurable functions A:T-->U_N(C). These
representations of O_N are constructed here from an orbit picture analysis of
the infinite-dimensional loop group.

</DOC>
<DOC>
<DOCNO> 84577 </DOCNO>
Compatibility of the expansive nondecelerative universe model with the


  Applying the Vaidya metrics in the model of Expansive Nondecelerative
Universe (ENU) leads to compatibility of the ENU model both with the classic
Newton gravitational theory and the general theory of relativity in weak fields

</DOC>
<DOC>
<DOCNO> 119418 </DOCNO>
On Estimating the QSO Transmission Power Spectrum


  We present new methods to minimize the systematic and random errors for
measuring the transmission power spectrum from the Lyman-alpha forest. Sources
of systematic errors explored include metal line contamination and
continuum-fitting. We advocate the technique of trend-removal in place of
traditional continuum-fitting -- here, a spectrum is normalized by its
(smoothly varying) mean rather than its continuum -- this method is easily
automated and removes biases introduced by continuum-fitting. Trend- removal
can be easily applied to spectra where continuum-fitting is difficult, such as
when the resolution or signal-to-noise is low, or for spectra at high
redshifts. Furthermore, a measurement of the continuum power spectrum using
trend-removal, from either low redshift quasar spectra or the red-side of
Lyman-alpha, allows in principle the removal of spurious power introduced by
the continuum and thereby expanding scales probed to larger ones. We also
derive expressions for the shot-noise bias and variance of the power spectrum
estimate, taking into account the non-Poissonian nature of the shot-noise and
the non-Gaussianity of the cosmic fluctuations. An appropriate minimum variance
weighting of the data is given. Finally, we give practical suggestions on
observing strategy: the desired resolution and S/N for different purposes, and
how to distribute one's finite observing time among quasar targets. Also
discussed is the quasar spectroscopic study of the Sloan Digital Sky Survey,
which has the potential to measure the power spectrum at z ~ 2-4 accurate to
better than 1 % per mode -- the techniques presented here will be useful for
tackling the anticipated issues of shot-noise and continuum contamination.

</DOC>
<DOC>
<DOCNO> 151780 </DOCNO>
On Noncommutative Solitons


  We consider 2+1-dimensional classical noncommutative scalar field theory. The
general ansatz for a radially symmetric solution is obtained. Some exact
solutions are presented. Their possible physical meaning is discussed. The case
of the finite $\theta$ is discussed qualitatively and illustrated by some
numerical results.

</DOC>
<DOC>
<DOCNO> 84673 </DOCNO>
Classical phase space structure induced by spontaneous symmetry breaking


  The collective dynamics of a many-body system is described as a special case
of low-energy quantum dynamics, occurring when the ground state breaks a
continuous symmetry of the Hamiltonian. This approach is applied to the
spontaneous breaking of the rotational symmetry of a nuclear Hamiltonian. It is
shown that the excitation operator of the isovector low-lying angular
oscillations in deformed nuclei is a linear combination between angular
momentum operators, which generate static rotations, and "angle" operators,
which generate the transition to a rotating frame.

</DOC>
<DOC>
<DOCNO> 99351 </DOCNO>
Propagation of Molecular Chaos by Quantum Systems and the Dynamics of


  The propagation of molecular chaos, a tool of classical kinetic theory, is
generalized to apply to quantum systems of distinguishable particles. We prove
that the Curie-Weiss model of ferromagnetism propagates molecular chaos and
derive the effective dynamics of a single-spin state in the mean-field limit.
Our treatment differs from the traditional approach to mean-field spin models
in that it concerns the dynamics of single-particle states instead of the
dynamics of infinite-particle states.

</DOC>
<DOC>
<DOCNO> 85619 </DOCNO>
Relativistic Quantum Scattering on a Cone


  We study the relativistic quantum mechanical scattering of a bosonic particle
by an infinite straight cosmic string, considering the non-minimal coupling
between the bosonic field and the scalar curvature. In this case, an effective
two-dimensional delta-function interaction takes place besides the usual
topological scattering and a renormalization procedure is necessary in order to
treat the problem that appears in connection with the delta-function.

</DOC>
<DOC>
<DOCNO> 116691 </DOCNO>
Polarized Protons in HERA


  Polarized proton beams at HERA can currently only be produced by extracting a
beam from a polarized source and then accelerating it in the three synchrotrons
at DESY. In this paper, the processes which can depolarize a proton beam in
circular accelerators are explained, devices which could avoid this
depolarization in the DESY accelerator chain are described, and specific
problems which become important at the high energies of HERA are mentioned. At
HERA's high energies, spin motion cannot be accurately described with the
isolated resonance model which has been successfully used for lower energy
rings. To illustrate the principles of more accurate simulations, the invariant
spin field is introduced to describe the equilibrium polarization state of a
beam and the changes during acceleration. It will be shown how linearized spin
motion leads to a computationally quick approximation for the invariant spin
field and how to amend this with more time consuming but accurate
non-perturbative computations. Analysis with these techniques has allowed us to
establish optimal Siberian Snake schemes for HERA.

</DOC>
<DOC>
<DOCNO> 13312 </DOCNO>
Comment on "A Kac-potential treatment of nonintegrable interactions" by


  We comment the recent manuscript by Vollmayr-Lee and Luijten
[cond-mat/0009031] focusing on classical systems with nonintegrable
interactions. The authors claim that they have proved that Boltzmann-Gibbs
statistics suffices for describing the system in thermal equilibrium. We show
that this statement is a misleading oversimplification since it only applies
for the $\lim_{N \to \infty} \lim_{t \to \infty}$ ordering, but certainly not
for the $\lim_{t \to \infty} \lim_{N \to \infty}$ one. The latter can even be
the {\it unique} physically meaningful situation for thermodynamically large
systems.

</DOC>
<DOC>
<DOCNO> 11469 </DOCNO>
The 1D Hubbard model within the Composite Operator Method


  Although effective for two dimensional (2D) systems, some approximations may
fail in describing the properties of one-dimensional (1D) models, which belong
to a different universality class. In this paper, we analyze the adequacy of
the Composite Operator Method (COM), which provides a good description of many
features of 2D strongly correlated systems, in grasping the physics of 1D
models. To this purpose, the 1D Hubbard model is studied within the framework
of the COM by considering a two-pole approximation and a paramagnetic ground
state. The local, thermodynamic and single-particle properties, the correlation
functions and susceptibilities are calculated in the case of half filling and
arbitrary filling. The results are compared with those obtained by the Bethe
Ansatz (BA) as well as by other numerical and analytical techniques. The
advantages and limitations of the method are analyzed in detail.

</DOC>
<DOC>
<DOCNO> 178445 </DOCNO>
Magnetic instability of quark matter


  Spontaneous magnetization of quark liquid is examined. It is pointed out that
quark liquid has potential to be ferromagnetic at rather low densities.

</DOC>
<DOC>
<DOCNO> 150517 </DOCNO>
Finite Temperature Casimir Effect for a Dilute Ball Satisfying $\epsilon


  The finite temperature Casimir free energy is calculated for a dielectric
ball of radius $a$ embedded in an infinite medium. The condition
$\epsilon\mu=1$ is assumed for the inside/outside regions. Both the Green
function method and the mode summation method are considered, and found to be
equivalent. For a dilute medium we find, assuming a simple "square" dispersion
relation with an abrupt cutoff at imaginary frequency $\hat \omega= \omega_0$,
the high temperature Casimir free energy to be negative and proportional to
$x_0 \equiv \omega_0 a$. Also, a physically more realistic dispersion relation
involving spatial dispersion is considered, and is shown to lead to comparable
results.

</DOC>
<DOC>
<DOCNO> 102406 </DOCNO>
Non-Extensive Bose-Einstein Condensation Model


  The imperfect Boson gas supplemented with a gentle repulsive interaction is
completely solved. In particular it is proved that it has non-extensive
Bose-Einstein condensation, i.e., there is condensation without macroscopic
occupation of the ground state (k=0) level.

</DOC>
<DOC>
<DOCNO> 169597 </DOCNO>
Quantum interfaces


  Rational agents acting as observers use ``knowables'' to construct a vision
of the outside world. Thereby, they are bound by the information exchanged with
what they consider to be objects. The cartesian cut or, in modern terminology,
the interface mediating this exchange, is again a construction. It serves as a
``scaffolding,'' an intermediate construction capable of providing the
necessary conceptual means. An attempt is made to formalize the interface, in
particular the quantum interface and quantum measurements, by a symbolic
information exchange. A principle of conservation of information is reviewed
and a measure of information flux through the interface is proposed.

</DOC>
<DOC>
<DOCNO> 85380 </DOCNO>
The mass of asymptotically anti-de Sitter space-times


  We give a definition of mass for spacelike hypersurfaces in space-times with
metrics which are asymptotic to the anti-de Sitter one, or to a class of
generalizations thereof. We present the results of gr-qc/0110014 which show
that our definition provides a geometric invariant for a spacelike hypersurface
embedded in a space-time. Some further global invariants are also given.

</DOC>
<DOC>
<DOCNO> 170310 </DOCNO>
Observation of power-law scaling for phase transitions in linear trapped


  We report an experimental confirmation of the power-law relationship between
the critical anisotropy parameter and ion number for the linear-to-zigzag phase
transition in an ionic crystal. Our experiment uses laser cooled calcium ions
confined in a linear radio-frequency trap. Measurements for up to 10 ions are
in good agreement with theoretical and numeric predictions. Implications on an
upper limit to the size of data registers in ion trap quantum computers are
discussed.

</DOC>
<DOC>
<DOCNO> 11112 </DOCNO>
Real inertons against hypothetical gravitons. Experimental proof of the


  Previously, one of the authors has suggested [Phys. Essays, vol. 6, 554
(1993); vol. 10, 407 (1997)] a mechanism of the particle motion within the
framework of a vacuum regarded as an original cellular medium, i.e. quantum
aether. The existence of special elementary excitations of the aether medium --
inertons -- around the particle has been the main peculiarity of that
mechanism. The present paper treats the impact of inertons on the collective
behaviour of atoms in a solid. It is shown that inertons should contribute to
the effective potential of interaction of atoms in the crystal lattice. The
possibility of separating this inerton contribution from the value of the atom
vibration amplitude is analysed. The experiment which assumes the presence of
the hypothetical inerton field is performed. The expected changes in the
structure of the test specimens caused by this field are in fact convincingly
fixed in micrographs.

</DOC>
<DOC>
<DOCNO> 10449 </DOCNO>
Stochastic strategies in the Minority Game


  We show analytically how the fluctuations (i.e. standard deviation) in the
Minority Game (MG) can decrease below the random coin-toss limit if the agents
use more general, stochastic strategies. This suppression of the standard
deviation results from a cancellation between the actions of a crowd, in which
agents act collectively and make the same decision, and an anticrowd in which
agents act collectively by making the opposite decision to the crowd.

</DOC>
<DOC>
<DOCNO> 12665 </DOCNO>
Temperature-dependent electron paramagnetic resonance studies of charge


  We report Electron Paramagnetic Resonance measurements on single crystalline
and powder samples of Nd_0.5Ca_0.5MnO_3 across the charge-ordering transition
at T_co=240 K down to the antiferromagnetic ordering transition at T_N = 140 K.
The changes in the linewidth, g-factor and intensity as functions of
temperature are studied to understand the nature of spin-dynamics in the
system. We explain the observed large decrease in the linewidth from T_N to
T_co in terms of motional narrowing caused by the hopping of the Jahn-Teller
polarons yielding an activation energy of E_a = 0.13 eV. Similar analysis of
data on Pr_0.6Ca_0.4MnO_3 published earlier gives E_a=0.2 eV. Below T_co, the
g-value increases continuously suggesting a gradual strengthening of the
orbital ordering. We give a qualitative explanation of the temperature
dependence and of the maximum in the asymmetry ratio A/B observed at T_co in
single crystal spectra which also supports the themodel of motional narrowing.

</DOC>
<DOC>
<DOCNO> 71748 </DOCNO>
Exploring CPT violation in $B\to J/\psi K$ decays using kaon


  We present an analysis of CPT violation in $B\to J/\psi K$ decays. A method
of kaon regeneration is proposed to increase the $K_{S(L)}$ interference
effects. With the time evolution of both neutral B and K mesons, we show that
it is possible to determine the CPT violating parameter in $B^0-\bar{B^0}$
mixing or constrain it.

</DOC>
<DOC>
<DOCNO> 70885 </DOCNO>
Global and Unified Analysis of Solar Neutrino Data


  We discuss the status of the solutions of the solar neutrino problem in terms
of oscillations of $\nu_e$ into active or sterile neutrinos. We present the
results of a global fit to the full data set corresponding to the latest data
presented at the $\nu$-2000 conference. We show the possible solutions in the
full parameter space including both MSW and vacuum, as well as quasi-vacuum
oscillations (QVO) and matter effects for mixing angles in the second octant
(the so called dark side). Our conclusion is that from the statistical point of
view, all solutions for oscillations into active neutrinos: LMA, LOW, SMA and
the QVO solutions are acceptable since they all provide a reasonable GOF to the
full data set. The same holds for the SMA solution for oscillations into
sterile neutrinos. LMA and LOW-QVO solutions for oscillations into active
neutrinos seem slightly favoured over SMA solutions for oscillations into
active or sterile neutrinos. We also analyze the dependence of these
conclusions on the uncertainty of the SSM $^8$B flux and on the removal of the
data from one of the experimental rates. We also present the results in the
framework of four neutrino oscillations which allows for oscillations into a
state which is a combination of active and sterile neutrino.

</DOC>
<DOC>
<DOCNO> 40099 </DOCNO>
Search for Direct CP Violation in Non-Leptonic Decays of Charged $\Xi$


  A search for direct CP violation in the non-leptonic decays of hyperons has
been performed. In comparing the product of the decay parameters,
$\alpha_{\Xi}\alpha_{\Lambda}$, in terms of an asymmetry parameter,
$A_{\Xi\Lambda}$, between hyperons and anti-hyperons in the charged $\Xi \to
\Lambda \pi$ and $\Lambda \to p \pi$ decay sequence, we found no evidence of
direct CP violations. The parameter $A_{\Xi\Lambda}$ was measured to be $0.012
\pm 0.014$.

</DOC>
<DOC>
<DOCNO> 151413 </DOCNO>
D-Branes on ALE Spaces and the ADE Classification of Conformal Field


  The spectrum of D2-branes wrapped on an ALE space of general ADE type is
determined, by representing them as boundary states of N=2 superconformal
minimal models. The stable quantum states have RR charges which precisely
represent the gauge fields of the corresponding Lie algebra. This provides a
simple and direct physical link between the ADE classification of N=2
superconformal field theories, and the corresponding root systems. An affine
extension of this structure is also considered, whose boundary states represent
the D2-branes plus additional D0-branes.

</DOC>
<DOC>
<DOCNO> 119138 </DOCNO>
A Note on Hydrodynamic Viscosity and Selfgravitation in Accretion Disks


  We propose a generalized accretion disk viscosity prescription based on
hydrodynamically driven turbulence at the critical effective Reynolds number.
This approach is consistent with recent re-analysis by Richard & Zahn (1999) of
experimental results on turbulent Couette-Taylor flows. This new
$\beta$-viscosity formulation is applied to both selfgravitating and
non-selfgravitating disks and is shown to yield the standard $\alpha$-disk
prescription in the case of shock dissipation limited, non-selfgravitating
disks. A specific case of fully selfgravitating $\beta$-disks is analyzed. We
suggest that such disks may explain the observed spectra of protoplanetary
disks and yield a natural explanation for the radial motions inferred from the
observed metallicity gradients in disk galaxies. The $\beta$-mechanism may also
account for the rapid mass transport required to power ultra luminous infrared
galaxies.

</DOC>
<DOC>
<DOCNO> 120421 </DOCNO>
Detecting Dark Matter in High Velocity Clouds


  Many high velocity HI clouds (HVCs) are now believed to be scattered
throughout the Galactic halo on scales of tens of kiloparsecs. Some of these
clouds appear to contain substantial HI masses (>10^6 Msun). It has been
suggested that these structures may be associated with dark matter `mini halos'
accreting onto the Galactic halo. For a compact HVC along the sight line to a
more distant galaxy, we demonstrate that `pixel gravitational lensing' provides
a crucial test for the presence of a dark halo in the form of massive compact
objects. The detection of pixel lensing will provide an independent means to
map the mass distribution within HVCs.

</DOC>
<DOC>
<DOCNO> 13298 </DOCNO>
High-Order Coupled Cluster Method Calculations for the Ground- and


  In this article, we present new results of high-order coupled cluster method
(CCM) calculations, based on a N\'eel model state with spins aligned in the
$z$-direction, for both the ground- and excited-state properties of the
spin-half {\it XXZ} model on the linear chain, the square lattice, and the
simple cubic lattice. In particular, the high-order CCM formalism is extended
to treat the excited states of lattice quantum spin systems for the first time.
Completely new results for the excitation energy gap of the spin-half {\it XXZ}
model for these lattices are thus determined. These high-order calculations are
based on a localised approximation scheme called the LSUB$m$ scheme in which we
retain all $k$-body correlations defined on all possible locales of $m$
adjacent lattice sites ($k \le m$). The ``raw'' CCM LSUB$m$ results are seen to
provide very good results for the ground-state energy, sublattice
magnetisation, and the value of the lowest-lying excitation energy for each of
these systems. However, in order to obtain even better results, two types of
extrapolation scheme of the LSUB$m$ results to the limit $m \to \infty$ (i.e.,
the exact solution in the thermodynamic limit) are presented. The extrapolated
results provide extremely accurate results for the ground- and excited-state
properties of these systems across a wide range of values of the anisotropy
parameter.

</DOC>
<DOC>
<DOCNO> 69324 </DOCNO>
Inclusive charmless semileptonic decay of \Lambda_b and Br(b ---> X_u l


  We study the inclusive charmless semileptonic decay of $\Lambda_b$,
$\Lambda_b \to X_u l \nu_l$, in the framework of heavy quark expansion and find
that the rate is substantially enhanced by spectator effect. We obtain $Br(b
\to X_u l \nu_l)$ to be $1.13 \times 10^{-3}$ for $|V_{ub}| = 3.3 \times
10^{-3}$. We discuss our result in light of the recent LEP measurements of the
charmless semileptonic branching ratio where such enhancement was not taken
into account in extracting $|V_{ub}|$.

</DOC>
<DOC>
<DOCNO> 8518 </DOCNO>
Acoustoelectric current and pumping in a ballistic quantum point contact


  The acoustoelectric current induced by a surface acoustic wave (SAW) in a
ballistic quantum point contact is considered using a quantum approach. We find
that the current is of the "pumping" type and is not related to drag, i.e. to
the momentum transfer from the wave to the electron gas. At gate voltages
corresponding to the plateaus of the quantized conductance the current is
small. It is peaked at the conductance step voltages. The peak current
oscillates and decays with increasing SAW wavenumber for short wavelengths.
These results contradict previous calculations, based on the classical
Boltzmann equation.

</DOC>
<DOC>
<DOCNO> 179001 </DOCNO>
Possibly to Test the Mechanism of Elastic Backward Proton-Deuteron


  The elastic backward proton-deuteron scattering is analyzed within a
covariant approach based on the invariant expansion of the reaction amplitude.
The relativistic invariant equations for all the polarization observables are
presented. Within the impulse approximation the relation of the tensor
analyzing power $T_{20}$ and the polarization transfer $\kappa_0$ to $P$-wave
components of the deuteron wave function is found. The comparison of the
theoretical calculations with experimental data is presented. An experimental
verification of the reaction mechanism is suggested by constructing some
combinations of different observables.

</DOC>
<DOC>
<DOCNO> 121812 </DOCNO>
Quiescent times in gamma-ray bursts: I. An observed correlation between


  Although more than 2000 astronomical gamma-ray bursts (GRBs) have been
detected, the precise progenitor responsible for these events is unknown. The
temporal phenomenology observed in GRBs can significantly constrain the
different models. Here we analyse the time histories of a sample of bright,
long GRBs, searching for the ones exhibiting relatively long (more than 5 per
cent of the total burst duration) quiescent times, defined as the intervals
between adjacent episodes of emission during which the gamma-rays count rate
drops to the background level. We find a quantitative relation between the
duration of an emission episode and the quiescent time elapsed since the
previous episode. We suggest here that the mechanism responsible for the
extraction and the dissipation of energy has to take place in a meta-stable
configuration, such that the longer the accumulation period, the higher is the
stored energy available for the next emission episode.

</DOC>
<DOC>
<DOCNO> 9516 </DOCNO>
High Temperature Charge-Ordering Fluctuation in Manganites


  High temperature (T) studies of La_{1-x}Ca_{x}MnO_{3} show that charge and
phonon transport is significantly suppressed in a narrow doping region of x~1/2
and in a wide T range up to 900 K, which accompanies anomalous broadening of
x-ray Bragg peaks. Contrarily, ferromagnetic (FM) correlation above Curie T is
sharply enhanced at x~3/8. All these observations indicate the presence of
short-range charge ordering (CO) correlation at high T, possibly in the form of
a FM "zigzag", a small segment of the CE-type CO state. The decoupling and
coupling of the FM zigzags for x~3/8 and 1/2, respectively, is consistent with
our results.

</DOC>
<DOC>
<DOCNO> 9727 </DOCNO>
Generalized Entropy Composition with Different q Indices: A Trial


  We analyze systematically composable composite entropy of two Tsallis
subsystems with different q indices. H-theorem and thermal balance relation are
commented.

</DOC>
<DOC>
<DOCNO> 69162 </DOCNO>
Production and Hadronization of Heavy Quarks


  Heavy long-lived quarks, i.e. charm and bottom, are frequently studied both
as tests of QCD and as probes for other physics aspects within and beyond the
standard model. The long life-time implies that charm and bottom hadrons are
formed and observed. This hadronization process cannot be studied in isolation,
but depends on the production environment. Within the framework of the string
model, a major effect is the drag from the other end of the string that the c/b
quark belongs to. In extreme cases, a small-mass string can collapse to a
single hadron, thereby giving a non-universal flavour composition to the
produced hadrons. We here develop and present a detailed model for the
charm/bottom hadronization process, involving the various aspects of string
fragmentation and collapse, and put it in the context of several heavy-flavour
production sources. Applications are presented from fixed-target to LHC
energies.

</DOC>
<DOC>
<DOCNO> 8924 </DOCNO>
Frequency dependence of the photonic noise spectrum in an absorbing or


  A theory is presented for the frequency dependence of the power spectrum of
photon current fluctuations originating from a disordered medium. Both the
cases of an absorbing medium (``grey body'') and of an amplifying medium
(``random laser'') are considered in a waveguide geometry. The semiclassical
approach (based on a Boltzmann-Langevin equation) is shown to be in complete
agreement with a fully quantum mechanical theory, provided that the effects of
wave localization can be neglected. The width of the peak in the power spectrum
around zero frequency is much smaller than the inverse coherence time,
characteristic for black-body radiation. Simple expressions for the shape of
this peak are obtained, in the absorbing case, for waveguide lengths large
compared to the absorption length, and, in the amplifying case, close to the
laser threshold.

</DOC>
<DOC>
<DOCNO> 71906 </DOCNO>
Hyperon Polarization in Inclusive Hadronic Production


  A QCD formula for the polarization in the large-p_T \Lambda hyperon
production in the unpolarized nucleon-nucleon collision at large x_F is
derived. We focus on the mechanism in which the chiral-odd spin-independent
twist-3 quark distribution E_F(x,x) becomes the source of the transversely
polarized quarks fragmenting into the polarized \Lambda. A simple model
estimate for that contribution shows the possibility that it gives rise to a
sizable \Lambda polarization.

</DOC>
<DOC>
<DOCNO> 10495 </DOCNO>
Comment on "Electronic fine structure in the electron-hole plasma of


  In this comment we point out several misleading conclusions reached by
Rodriguez et al. [PRL 84, 3903 (2000) and cond-mat/0003201] about the details
of the band structure in SrB_6 and their role in interpreting the
high-temperature weak ferromagnetism, which develops in this material upon
doping.

</DOC>
<DOC>
<DOCNO> 119469 </DOCNO>
On the transition to self-gravity in low mass AGN and YSO accretion


  The equations governing the vertical structure of a stationary keplerian
accretion disc are presented. The model is based on the alpha-viscosity,
includes self-gravity, convective transport and turbulent pressure. A few
properties of the model are discussed for circumstellar and AGN discs.
  We show the strong sensitivity of the disc structure to the viscous energy
deposition towards the vertical axis, specially when entering inside the
self-gravitating part of the disc. The local version of the alpha-prescription
leads to a "singular" behavior which is also predicted by the vertically
averaged model. With respect, a much softer transition is observed with the
 "alpha-P" formalism. Turbulent pressure is important only for alpha > 0.1. It
lowers vertical density gradients, significantly thickens the disc, tends to
wash out density inversions and pushes the self-gravitating region to slightly
larger radii. Curves localizing the inner edge of the self-gravitating disc as
functions of the viscosity parameter and accretion rate are given. The lower
alpha, the closer to the center the self-gravitating regime, and the
sensitivity to the accretion rate is generally weak, except for alpha < 0.1.
This study suggests that models aiming to describe T-Tauri discs beyond about a
few to a few tens astronomical units from the central protostar using the
alpha-theory should consider vertical self-gravity. The Primitive Solar Nebula
was probably a bit (if not strongly) self-gravitating at the actual orbit of
giant planets. Alpha-discs hosted by active galaxies are self-gravitating
beyond about a thousand Schwarzchild radii. The inferred surface density
remains too high to lower the accretion time scale. More efficient mechanisms
driving accretion are required.

</DOC>
<DOC>
<DOCNO> 40093 </DOCNO>
Higgs Searches at the Tevatron


  Higgs hunting is a world-wide sport and the Tevatron is set to become the
next field of play when Run II starts in March 2001. To set the stage, we
summarize results of searches for standard and non-standard Higgs bosons by CDF
and Dzero in Run I at the Tevatron. Progress has been made in quantifying the
requirements on the Tevatron Collider and on the upgraded experiments in Run II
for extending the excellent work done at LEP. Armed with parameterizations of
expected detector performance, the Tevatron Higgs Working group has made
predictions of the sensitivity of CDF and Dzero to Higgs bosons in the Standard
Model and in its Minimal Supersymmetric extension as a function of integrated
luminosity. These predictions are presented to underscore the excitement being
generated by Run II, and to highlight the need for the highest possible
luminosity.

</DOC>
<DOC>
<DOCNO> 119636 </DOCNO>
Pulsational instability domain of Delta Scuti variables


  An updated theoretical instability domain of the Delta Scuti star models in
the Hertzsprung-Russell diagram, in the log g - log Teff diagram and in
diagrams for dereddened uvby-beta photometric indices is presented. The
sensitivity of both the position of the evolutionary tracks and the Blue Edge
of the instability domain to changes in the chemical composition parameters (X,
Z) and to changes in the convection theory parameters (mixing-length in the
stellar envelope, the extent of the overshooting from the convective core) is
discussed.

</DOC>
<DOC>
<DOCNO> 7632 </DOCNO>
Andreev interferometry as a probe of superconducting phase correlations


  Andreev interferometry - the sensitivity of the tunneling current to spatial
variations in the local superconducting order at an interface - is proposed as
a probe of the spatial structure of the phase correlations in the pseudogap
state of the cuprate superconductors. To demonstrate this idea theoretically, a
simple tunneling model is considered, via which the tunneling current is
related to the equilibrium phase-phase correlator in the pseudogap state. These
considerations suggest that measurement of the low-voltage conductance through
mesoscopic contacts of varying areas provides a scheme for accessing
phase-phase correlation information. For illustrative purposes, quantitative
predictions are made for a model of the pseudogap state in which the phase (but
not the amplitude) of the superconducting order varies randomly, and does so
with correlations consistent with certain proposed pictures of the pseudogap
state.

</DOC>
<DOC>
<DOCNO> 68464 </DOCNO>
CP violating phase and quark mixing angles from flavour permutational


  The phase equivalence of the theoretical quark mixing matrix ${\bf V}^{th}$
derived from the breaking of the flavour permutational symmetry and the
phenomenological parametrizations ${\bf V}^{PDG}$ and ${\bf V}^{KM}$ is
explicitly exhibited. From here, we derive exact explicit expressions for the
three mixing angles and the CP violating phase of the two phenomenological
parametrizations in terms of the quark mass ratios $(m_{u}/m_{t}, m_{c}/m_{t},
m_{d}/m_{b}, m_{s}/m_{b})$ and the parameters $Z^{*1/2}$ and $\Phi^*$
characterizing the preferred symmetry breaking pattern. The computed values for
the CP violating phase and the mixing angles of the standard parametrization
advocated by the Particle Data Group are $\delta^*_{13}=73.2^\circ$,
$\sin\theta^*_{12}=0.222$,
 $\sin\theta^*_{13}=0.0036$, and $\sin\theta^*_{23}=0.040$. The computed values
of the CP-violating phase and the mixing angles of the Kobayashi-Maskawa
parametrization are $\delta^*_{KM}=96.4^\circ$, $\sin\theta^*_{1}=0.2225$,
$\sin\theta^*_{2}=0.0384$, and $\sin\theta^*_{3}=0.0162$. In both cases, the
numerical values of the mixing angles and CP-violating phase computed from
quark masses and the flavour symmetry breaking parameters coincide almost
exactly with the central values of the same parameters obtained from a fit to
experimental data.

</DOC>
<DOC>
<DOCNO> 70445 </DOCNO>
Kinematic Effects in Quarkonia Production


  We investigate energy (momentum) distributions in J/Psi photoproduction and
J/Psi production in B meson decay. In particular the upper endpoint region of
the spectrum is examined where the effect of soft gluon emission from the ccbar
pair becomes important. Constructing a model which is consistent with the
so-called shape function formalism we consider these fragmentation effects and
show that the relevance of possible colour octet contributions in the
photoproduction channel is still inconclusive.

</DOC>
<DOC>
<DOCNO> 118301 </DOCNO>
The Morphology, Color, and Gas Content of Low Surface Brightness


  Recent surveys have discovered hundreds of low surface brightness galaxies,
systems with central surface brightness fainter than 22.0 B mag arcsec^-2, in
the local universe. Plots of the surface brightness distribution - that is, the
space density of galaxies plotted against central surface brightness - show a
flat space density distribution from the canonical Freeman value of 21.65
through the current observational limit of 25.0 B mag arcsec^-2. It is
therefore extremely important to understand these diffuse systems if we wish to
understand galaxy formation and evolution as a whole. This talk is a review of
both the known properties of low surface brightness galaxies and of popular
theories describing the formation and evolution of these enigmatic systems.

</DOC>
<DOC>
<DOCNO> 40631 </DOCNO>
The BABAR measurement of sin2beta and its future prospects


  The measurement of sin2beta by the BABAR experiment, where beta is one of the
angles of the Unitarity Triangle, is described. Some prospects for the future
of the measurement are also discussed.

</DOC>
<DOC>
<DOCNO> 118723 </DOCNO>
A Theory of Gamma-Ray Bursts


  We present a specific scenario for the link between GRB and hypernovae, based
on Blandford-Znajek extraction of black-hole spin energy. Such a mechanism
requires a high angular momentum in the progenitor object. The observed
association of gamma-ray bursts with type Ibc supernovae leads us to consider
massive helium stars that form black holes at the end of their lives as
progenitors. We combine the numerical work of MacFadyen & Woosley with analytic
calculations, to show that about 1E53 erg each are available to drive the fast
GRB ejecta and the supernova. The GRB ejecta are driven by the power output
through the open field lines, whereas the supernova is powered by closed filed
lines and jet shocks. We also present a much simplified approximate derivation
of these energetics.
  Helium stars that leave massive black-hole remnants in special ways, namely
via soft X-ray transients or very massive WNL stars. Since binaries naturally
have high angular momentum, we propose a link between black-hole transients and
gamma-ray bursts. Recent observations of one such transient, GRO J1655-40/Nova
Scorpii 1994, explicitly support this connection: its high space velocity
indicates that substantial mass was ejected in the formation of the black hole,
and the overabundance of alpha-nuclei, especially sulphur, indicates that the
explosion energy was extreme, as in SN 1998bw/GRB 980425. (abstract shortened)

</DOC>
<DOC>
<DOCNO> 67936 </DOCNO>
Probe of CP Violation in e+e- -> ttbar Near Threshold


  We study how to probe the anomalous CP-violating couplings of top quark with
photon, Z and gluon in the ttbar threshold region at future e+e- colliders.
These couplings contribute to the difference of the t and tbar polarization
vectors delta P and to the CP-odd spin correlation tensor delta Q_ij. We find
that typical sizes of delta P and delta Q_ij are 5-20% times the couplings
(d_tgamma, d_tZ, d_tg) in the threshold region. Experimentally delta P can be
measured efficiently using the CP-odd combination of the l+/l- momenta or of
the l+/l- directions. We have similar sensitivities to both the real and
imaginary parts of the couplings independently using the two components of
delta P. Taking advantage of different dependences of delta P on the e+/e-
polarizations and on the c.m. energy, we will be able to disentangle the
effects of the three couplings d_tgamma, d_tZ, d_tg in the ttbar threshold
region. We give rough estimates of sensitivities to the anomalous couplings
expected at future e+e- colliders. The sensitivities to d_tgamma and d_tZ are
comparable to those attainable in the open-top region at e+e- colliders. The
sensitivity to d_tg is worse than that expected at a hadron collider but
exceeds the sensitivity in the open-top region at e+e- colliders.

</DOC>
<DOC>
<DOCNO> 69546 </DOCNO>
Uncertainties of Parton Distribution Functions and Their Implications on


  We describe preliminary results from an effort to quantify the uncertainties
in parton distribution functions and the resulting uncertainties in predicted
physical quantities. The production cross section of the $W$ boson is given as
a first example. Constraints due to the full data sets of the CTEQ global
analysis are used in this study. Two complementary approaches, based on the
Hessian and the Lagrange multiplier method respectively, are outlined. We
discuss issues on obtaining meaningful uncertainty estimates that include the
effect of correlated experimental systematic uncertainties and illustrate them
with detailed calculations using one set of precision DIS data.

</DOC>
<DOC>
<DOCNO> 71489 </DOCNO>
QCD phase transition and primordial density perturbations


  We analyze the effect of primordial density perturbations on the cosmic QCD
phase transition. According to our results hadron bubbles nucleate at the cold
perturbations. We call this mechanism inhomogeneous nucleation. We find the
typical distance between bubble centers to be a few meters. This exceeds the
estimates from homogeneous nucleation by two orders of magnitude. The resulting
baryon inhomogeneities may affect primordial nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 70837 </DOCNO>
Light hadronic physics using domain wall fermions in quenched lattice


  In the past year domain wall fermion simulations have moved from exploratory
stages to the point where systematic effects can be studied with different
gauge couplings, volumes, and lengths in the fifth dimension. Results are
presented here for the chiral condensate, the light hadron spectrum, and the
strange quark mass. We focus especially on the pseudoscalar meson mass and show
that, in small volume, the correlators used to compute it can be contaminated
to different degrees by topological zero modes. In large volume a nonlinear
extrapolation to the chiral limit, e.g. as expected from quenched chiral
perturbation theory, is needed in order to have a consistent picture of low
energy chiral symmetry breaking effects.

</DOC>
<DOC>
<DOCNO> 68361 </DOCNO>
Direct and indirect limits on the electro-magnetic form factors of WIMPs


  We use the results of direct and indirect searches for weakly interacting
massive particles (WIMPs) to obtain bounds on various electro-magnetic form
factors of WIMPs. The limits on the recoil signal in underground dark matter
detection experiments, with standard assumptions about the density and r.m.s.
velocity of WIMPs in the halo, can be translated into the following
model-independent bounds on the magnetic dipole, electric dipole, quadrupole
and anapole moments and the polarizability of WIMPs: mu/mu_n < 1.4 10^{-4}, d <
5 10^{-21}e cm, Q < 6 10^{-7}fm^2, a/mu_n < 3 10^{-2} fm, and chi < 5
10^{-8}fm^3 for a WIMP mass of 100 GeV. The limits on fluxes of highly
energetic neutrinos produced in the annihilation of WIMPs in the center of the
earth and the sun lead to somewhat stronger, but more model dependent bounds.

</DOC>
<DOC>
<DOCNO> 9682 </DOCNO>
Polyelectrolyte gels in poor solvent: Equilibrium and non equilibrium


  We study theoretically using scaling arguments the behavior of
polyelectrolyte gels in poor solvents. Following the classical picture of
Katchalsky, our approach is based on single chain elasticity but it accounts
for the recently proposed pearl-necklace structure of polyelectrolytes in poor
solvents. The elasticity both of gels at swelling equilibrium and of partially
swollen, non equilibrium, gels is studied when parameters such as the ionic
strength or the fraction of charged monomers are varied. Our theory could be
useful to interpret recent experiments performed in Strasbourg that show that
if identical gel samples are swollen to the same extent at different pH the
sample with the highest charge has the lowest shear modulus.

</DOC>
<DOC>
<DOCNO> 102320 </DOCNO>
Stokes Matrices and Poisson Lie Groups


  We point out, and draw some consequences of, the fact that the Poisson Lie
group G* dual to G=GL_n(C) (with its standard complex Poisson structure) may be
identified with a certain moduli space of meromorphic connections on the unit
disc having an irregular singularity at the origin. The Riemann-Hilbert map for
such connections, taking the Stokes data, induces a holomorphic map from the
dual of the Lie algebra of G to the Poisson Lie group G*. The main result is
that this map is Poisson.
  First this leads to new, more direct, proofs of theorems of Duistermaat and
Ginzburg-Weinstein (enabling one to reduce Kostant's non-linear convexity
theorem, involving the Iwasawa projection, to the linear convexity theorem,
involving the `diagonal part').
  Secondly we obtain a new approach to the braid group invariant Poisson
structure on Dubrovin's local moduli space of semisimple Frobenius manifolds:
it is induced from the standard Poisson structure on G*.

</DOC>
<DOC>
<DOCNO> 100795 </DOCNO>
Peculiarities of inclined force action upon one-dimensional homogeneous


  Exact analytic solutions for one-dimensional elastic lumped line under
affection of external force inclined to the axe of line is analyzed. It is
shown that in this case an inclined wave being described by implicit function
propagates along the line. The conclusions were extended both to unforced
vibrations in the line and to distributed-parameters line vibrations. Solution
in the form of implicit function is proved as a generalizing one for the wave
equation

</DOC>
<DOC>
<DOCNO> 10482 </DOCNO>
Edge Dynamics in Quantum Hall Bilayers II: Exact Results with Disorder


  We study edge dynamics in the presence of interlayer tunneling, parallel
magnetic field, and various types of disorder for two infinite sequences of
quantum Hall states in symmetric bilayers. These sequences begin with the 110
and 331 Halperin states and include their fractional descendants at lower
filling factors; the former is easily realized experimentally while the latter
is a candidate for the experimentally observed quantum Hall state at a total
filling factor of 1/2 in bilayers. We discuss the experimentally interesting
observables that involve just one chiral edge of the sample and the correlation
functions needed for computing them. We present several methods for obtaining
exact results in the presence of interactions and disorder which rely on the
chiral character of the system. Of particular interest are our results on the
331 state which suggest that a time-resolved measurement at the edge can be
used to discriminate between the 331 and Pfaffian scenarios for the observed
quantum Hall state at filling factor 1/2 in realistic double-layer systems.

</DOC>
<DOC>
<DOCNO> 9532 </DOCNO>
Spatial Inhomogeneities in Disordered d-Wave Superconductors: Effect on


  We study a short coherence length d-wave superconductor with finite density
of unitary scatterers using the Bogoliubov-deGennes technique. We find that the
low-energy density of states is reduced, the superfluid stiffness is
significantly larger and off-diagonal long range order is more robust than the
self-consistent T-matrix prediction. These results are a consequence of the
inhomogeneous pairing amplitude in the ground state and of the low-lying
excitations formed by hybridized impurity resonances. These features, with
their nontrivial spatial structure, cannot be adequately described within the
conventional T-matrix approach.

</DOC>
<DOC>
<DOCNO> 117687 </DOCNO>
The X-ray properties of luminous infrared galaxies and their


  We present a study of a sample of luminous infrared galaxies (LIGs, L_IR >
10^11 L_sun) observed in the hard (2-10 keV) X rays. The main results are: 1)
most LIGs are powered both by AGN and starburst activity; 2) the AGNs in our
sample are absorbed in the infrared by a lower N_H than in the X rays or,
alternatively, the dust-to-gas ratio is lower than galactic; 3) the study of a
subsample of sources observed in the 20-200 keV band indicates that most of the
AGNs hosted by the LIGs are heavily obscured up to 100 keV and, therefore,
their contribution to the X-ray background must be small.

</DOC>
<DOC>
<DOCNO> 119041 </DOCNO>
Scalar fields in an anisotropic closed universe


  We study in this article a class of homogeneous, but anisotropic cosmological
models in which shear viscosity is included. Within the matter content we
consider a component (the quintessence component) determined by the barotropic
equations of state, $p=\alpha \rho$, with $\alpha < 0$. We establish conditions
under which a closed axisymmetrical cosmological model may look flat al low
redshift.

</DOC>
<DOC>
<DOCNO> 72296 </DOCNO>
Staying Thermal with Hartree Ensemble Approximations


  We study thermal behavior of a recently introduced Hartree ensemble
approximation, which allows for non-perturbative inhomogeneous field
configurations as well as for approximate thermalization, in the $\phi^4$ model
in 1+1 dimensions. Using ensembles with a free field thermal distribution as
out-of-equilibrium initial conditions we determine thermalization time scales.
The time scale for which the system stays in approximate quantum thermal
equilibrium is an indication of the time scales for which the approximation
method stays reasonable. This time scale turns out to be two orders of
magnitude larger than the time scale for thermalization, in the range of
couplings and temperatures studied. We also discuss simplifications of our
method which are numerically more efficient and make a comparison with
classical dynamics.

</DOC>
<DOC>
<DOCNO> 118914 </DOCNO>
Microlensing extended stellar sources


  We have developed a code to compute multi-colour microlensing lightcurves for
extended sources, including the effects of limb darkening and photospheric star
spots as a function of spot temperature, position, size and lens trajectory.
Our model also includes the effect of structure within the spot and rotation of
the stellar source.
  Our results indicate that star spots generally give a clear signature only
for transit events. Moreover, this signature is strongly suppressed by limb
darkening for spots close to the limb -- although such spots can be detected by
favourable lens trajectories.

</DOC>
<DOC>
<DOCNO> 99410 </DOCNO>
Local tree-width, excluded minors, and approximation algorithms


  The local tree-width of a graph G=(V,E) is the function ltw^G: N -> N that
associates with every natural number r the maximal tree-width of an
r-neighborhood in G. Our main graph theoretic result is a decomposition theorem
for graphs with excluded minors that essentially says that such graphs can be
decomposed into trees of graphs of bounded local tree-width.
  As an application of this theorem, we show that a number of combinatorial
optimization problems, such as Minimum Vertex Cover, Minimum Dominating Set,
and Maximum Independent Set have a polynomial time approximation scheme when
restricted to a class of graphs with an excluded minor.

</DOC>
<DOC>
<DOCNO> 116338 </DOCNO>
Feasibility of backward diffraction radiation for non-destructive


  The characteristics of backward diffraction radiation (BDR), i.e. radiation
of the charged particle passing through a slit in the tilted screen, has been
considered. The technique for non-destructive beam diagnostics based on the
measurements of BDR yield for different tilted angles (theta-scan) is
suggested.

</DOC>
<DOC>
<DOCNO> 67704 </DOCNO>
Dynamics of Hot Bulk QCD Matter: from the Quark-Gluon Plasma to Hadronic


  We introduce a combined macroscopic/microscopic transport approach employing
relativistic hydrodynamics for the early, dense, deconfined stage of the
reaction and a microscopic non-equilibrium model for the later hadronic stage
where the equilibrium assumptions are not valid anymore. Within this approach
we study the dynamics of hot, bulk QCD matter, which is expected to be created
in ultra-relativistic heavy ion collisions at the SPS, the RHIC and the LHC.
Our approach is capable of self-consistently calculating the freeze-out of the
hadronic system, while accounting for the collective flow on the hadronization
hypersurface generated by the QGP expansion. In particular, we perform a
detailed analysis of the reaction dynamics, hadronic freeze-out, and transverse
flow.

</DOC>
<DOC>
<DOCNO> 100301 </DOCNO>
A structure and representations of diffeomorphism groups of


  Diffeomorphism groups $G$ of manifolds $M$ on locally $\bf F$-convex spaces
over non-Archimedean fields $\bf F$ are investigated. It is shown that their
structure has many differences with the diffeomorphism groups of real and
complex manifolds. It is proved that $G$ is not a Banach-Lie group, but it has
a neighbourhood $W$ of the unit element $e$ such that each element $g$ in $W$
belongs to at least one corresponding one-parameter subgroup.
   It is proved that $G$ is simple and perfect. Its compact subgroups $G_c$ are
studied such that a dimension over $\bf F$ of its tangent space $dim_{\bf
F}T_eG_c$ in $e$ may be infinite. This is used for decompositions of continuous
representations into irreducible and investigations of induced representations.

</DOC>
<DOC>
<DOCNO> 9663 </DOCNO>
Surprises in Diffuse Scattering


  Diffuse scattering is usually associated with some disorder in the analyzed
material. Different kinds of disorder may produce different diffuse scattering
-- or not. In this letter, we demonstrate some aspects of the variety of
diffuse scattering that occurs even in very simple examples, and how
unawareness may lead astray.

</DOC>
<DOC>
<DOCNO> 121246 </DOCNO>
On the Timescale for the Formation of Protostellar Cores in Magnetic


  We revisit the problem of the formation of dense protostellar cores due to
ambipolar diffusion within magnetically supported molecular clouds, and derive
an analytical expression for the core formation timescale. The resulting
expression is similar to the canonical expression = t_{ff}^2/t_{ni} ~ 10 t_{ni}
(where t_{ff} is the free-fall time and t_{ni} is the neutral-ion collision
time), except that it is multiplied by a numerical factor C(\mu_{c0}), where
\mu_{c0} is the initial central mass-to-flux ratio normalized to the critical
value for gravitational collapse. C(\mu_{c0}) is typically ~ 1 in highly
subcritical clouds (\mu_{c0} << 1), although certain conditions allow
C(\mu_{c0}) >> 1. For clouds that are not highly subcritical, C(\mu_{c0}) can
be much less than unity, with C(\mu_{c0}) --> 0 for \mu_{c0} --> 1,
significantly reducing the time required to form a supercritical core. This,
along with recent observations of clouds with mass-to-flux ratios close to the
critical value, may reconcile the results of ambipolar diffusion models with
statistical analyses of cores and YSO's which suggest an evolutionary timescale
\~ 1 Myr for objects of mean density ~ 10^4 cm^{-3}. We compare our analytical
relation to the results of numerical simulations, and also discuss the effects
of dust grains on the core formation timescale.

</DOC>
<DOC>
<DOCNO> 68732 </DOCNO>
Six Dimensional Topological Gravity and the Cosmological Constant


  We formulate a topological theory in six dimensions with gauge group SO(3,3)
which reduces to gravity on a four dimensional defect if suitable boundary
conditions are chosen. In such a framework we implement the reflection
automorphism of SO(3,3) as a $\Z2$ symmetry which forbids the appearance of a
gravitational cosmological constant. Some temptative speculations are presented
also for the possible inclusion of the matter contribution at a full quantum
level.

</DOC>
<DOC>
<DOCNO> 10588 </DOCNO>
Quantum to classical crossover in the 2D easy-plane XXZ model


  Ground-state and thermodynamical properties of the spin-1/2 two-dimensional
easy-plane XXZ model are investigated by both a Green's-function approach and
by Lanczos diagonalizations on lattices with up to 36 sites. We calculate the
spatial and temperature dependences of various spin correlation functions, as
well as the wave-vector dependence of the spin susceptibility for all
anisotropy parameters $\Delta$. In the easy--plane ferromagnetic region $(-1<
\Delta < 0)$, the longitudinal correlators of spins at distance $r$ change sign
at a finite temperature $T_0(\Delta, {\bf r})$. This transition, observed in
the 2D case for the first time, can be interpreted as a quantum to classical
crossover.

</DOC>
<DOC>
<DOCNO> 67992 </DOCNO>
Unitarized Heavy Baryon Chiral Perturbation Theory and the $\Delta$


  Based on the recent phenomenological analysis done by M. Mojzis, Eur. Phys.
Jour. {\bf C2} (1998) 182, of $\pi N $ scattering within the framework of Heavy
Baryon Chiral Perturbation Theory we predict, after a suitable unitarization of
the amplitude, the $\Delta$ resonance at $\sqrt{s} = M_\Delta = 1238
\er{22}{18}{\rm MeV} $ and with a width of $ \Gamma_\Delta = 150 \er{43}{31}
{\rm MeV} $ in excellent agreement with the experimental numbers. The error
bars reflect only the uncertainties in the low energy parameters as determined
from an extrapolation to threshold of experimental data. We also describe
satisfactorily, within errors, the phase shifts up to $\sqrt{s} \sim 1300 {\rm
MeV} $.

</DOC>
<DOC>
<DOCNO> 170716 </DOCNO>
New high-efficiency source of photon pairs for engineering quantum


  We have constructed an efficient source of photon pairs using a
waveguide-type nonlinear device and performed a two-photon interference
experiment with an unbalanced Michelson interferometer. Parametric
down-converted photons from the nonlinear device are detected by two detectors
located at the output ports of the interferometer. Because the interferometer
is constructed with two optical paths of different length, photons from the
shorter path arrive at the detector earlier than those from the longer path. We
find that the difference of arrival time and the time window of the coincidence
counter are important parameters which determine the boundary between the
classical and quantum regime. When the time window of the coincidence counter
is smaller than the arrival time difference, fringes of high visibility
(80$\pm$ 10%) were observed. This result is only explained by quantum theory
and is clear evidence for quantum entanglement of the interferometer's optical
paths.

</DOC>
<DOC>
<DOCNO> 84644 </DOCNO>
Self-Dual Conformal Supergravity and the Hamiltonian Formulation


  In terms of Dirac matrices the self-dual and anti-self-dual decomposition of
a conformal supergravity is given and a self-dual conformal supergravity theory
is developed as a connection dynamic theory in which the basic dynamic variabes
include the self-dual spin connection i.e. the Ashtekar connection rather than
the triad. The Hamiltonian formulation and the constraints are obtained by
using the Dirac-Bergmann algorithm.
    PACS numbers: 04.20.Cv, 04.20.Fy,04.65.+e

</DOC>
<DOC>
<DOCNO> 9868 </DOCNO>
Bose-Einstein condensation in trapped dipolar gases


  We discuss Bose-Einstein condensation in a trapped gas of bosonic particles
interacting dominantly via dipole-dipole forces. We find that in this case the
mean-field interparticle interaction and, hence, the stability diagram are
governed by the trapping geometry. Possible physical realisations include
ultracold heteronuclear molecules, or atoms with laser induced electric dipole
moments.

</DOC>
<DOC>
<DOCNO> 121119 </DOCNO>
A toroidal black hole for the AGN phenomenon


  A new approach to the study of the AGN phenomenon is proposed, in which the
nucleus activity is related to the metric of the inner massive black hole. The
possibility of a Toroidal Black Hole (TBH), in contrast to the usual Spherical
Black Hole (SBH), is discussed as a powerful tool in understanding AGN related
phenomena, such as the energetics, the production of jets and the acceleration
of particles, the shape of the magnetic field and the lifetime of nucleus
activity.

</DOC>
<DOC>
<DOCNO> 116664 </DOCNO>
Radial Viscous Flow between Two Parallel Annular Plates


  An analytic solution to the linearized Navier-Stokes equation is given that
describes the radial flow of an incompressible, viscous fluid between two
parallel, concentric annular plates.

</DOC>
<DOC>
<DOCNO> 169801 </DOCNO>
Dynamics of Nonlocality for A Two-Mode Squeezed State in Thermal


  We investigate the time evolution of nonlocality for a two-mode squeezed
state in the thermal environment. The initial two-mode pure squeezed state is
nonlocal with a stronger nonlocality for a larger degree of squeezing. It is
found that the larger the degree of initial squeezing is, the more rapidly the
squeezed state loses its nonlocality. We explain this by the rapid destruction
of quantum coherence for the strongly squeezed state.

</DOC>
<DOC>
<DOCNO> 170677 </DOCNO>
Dynamical diffraction in sinusoidal potentials: uniform approximations


  Eigenvalues and eigenfunctions of Mathieu's equation are found in the short
wavelength limit using a uniform approximation (method of comparison with a
`known' equation having the same classical turning point structure) applied in
Fourier space. The uniform approximation used here relies upon the fact that by
passing into Fourier space the Mathieu equation can be mapped onto the simpler
problem of a double well potential. The resulting eigenfunctions (Bloch waves),
which are uniformly valid for all angles, are then used to describe the
semiclassical scattering of waves by potentials varying sinusoidally in one
direction. In such situations, for instance in the diffraction of atoms by
gratings made of light, it is common to make the Raman-Nath approximation which
ignores the motion of the atoms inside the grating. When using the
eigenfunctions no such approximation is made so that the dynamical diffraction
regime (long interaction time) can be explored.

</DOC>
<DOC>
<DOCNO> 10722 </DOCNO>
Failure of the Migdal-Eliashberg Theory of Superconductivity in Rb_3C_60


  We discuss the compatibility of the most accurate experimental data with the
ordinary Migdal-Eliashberg theory of superconductivity in the fullerene
compound Rb_3C_60. By using different model phonon spectra we conclude that the
experimental data can be fitted only by invoking an electron-phonon coupling of
order \lambda\simeq 3. This exceedingly high value is unphysical and it is not
consistent with the basic assumptions of the Migdal-Eliashberg theory. On the
contrary, by relaxing the adiabatic hypothesis on which the Migdal-Eliashberg
theory rests, the experimental data can be fitted by much more realistic values
of \lambda. This generalized theory predicts also characteristic features
absent in the Migdal-Eliashberg framework which can be experimentally tested.

</DOC>
<DOC>
<DOCNO> 7644 </DOCNO>
Plaquette Ground State in the Two-dimensional SU(4) Spin-Orbital Model


  In order to understand the properties of Mott insulators with strong ground
state orbital fluctuations, we study the zero temperature properties of the
SU(4) spin-orbital model on a square lattice. Exact diagonalizations of finite
clusters suggest that the ground state is disordered with a singlet-multiplet
gap and possibly low-lying SU(4) singlets in the gap. An interpretation in
terms of plaquette SU(4) singlets is proposed. The implications for LiNiO_2 are
discussed.

</DOC>
<DOC>
<DOCNO> 39959 </DOCNO>
Search for CP violation in D0 and D+ decays


  A high statistics sample of photoproduced charm particles from the FOCUS
(E831) experiment at Fermilab has been used to search for CP violation in the
Cabibbo suppressed decay modes D+ to K-K+pi+, D0 to K-K+ and D0 to pi-pi+. We
have measured the following CP asymmetry parameters: A_CP(K-K+pi+) = +0.006 +/-
0.011 +/- 0.005, A_CP(K-K+) = -0.001 +/- 0.022 +/- 0.015 and A_CP(pi-pi+) =
+0.048 +/- 0.039 +/- 0.025 where the first error is statistical and the second
error is systematic. These asymmetries are consistent with zero with smaller
errors than previous measurements.

</DOC>
<DOC>
<DOCNO> 8806 </DOCNO>
Signatures of the excitonic memory effects in four-wave mixing processes


  We report the signatures of the exciton correlation effects with finite
memory time in frequency domain degenerate four-wave mixing (DFWM) in
semiconductor microcavity. By utilizing the polarization selection rules, we
discriminate instantaneous, mean field interactions between excitons with the
same spins, long-living correlation due to the formation of biexciton state by
excitons with opposite spins, and short-memory correlation effects in the
continuum of unbound two-exciton states. The DFWM spectra give us the relative
contributions of these effects and the upper limit for the time of the
exciton-exciton correlation in the unbound two-exciton continuum. The obtained
results reveal the basis of the cavity polariton scattering model for the DFWM
processes in high-Q GaAs microcavity.

</DOC>
<DOC>
<DOCNO> 101947 </DOCNO>
Fundamental groups of line arrangements: Enumerative aspects


  This is a survey of some recent developments in the study of complements of
line arrangements in the complex plane. We investigate the fundamental groups
and finite covers of those complements, focusing on homological and enumerative
aspects. The unifying framework for this study is the stratification of the
character variety of the fundamental group, G, by the jumping loci for
cohomology with coefficients in rank 1 local systems. Counting certain torsion
points on these "characteristic" varieties yields information about the
homology of branched and unbranched covers of the complement, as well as on the
number of low-index subgroups of its fundamental group. We conclude with two
conjectures, expressing the lower central series quotients of G/G'' (and, in
some cases, G itself) in terms of the closely related "resonance" varieties. We
illustrate the discussion with a number of detailed examples, some of which
reveal new phenomena.

</DOC>
<DOC>
<DOCNO> 69021 </DOCNO>
Second Cluster Integral and Excluded Volume Effects for the Pion Gas


  The quantum mechanical formula for Mayer's second cluster integral for the
gas of relativistic particles with hard-core interaction is derived. The proper
pion volume calculated with quantum mechanical formula is found to be an order
of magnitude larger than its classical evaluation.
  The second cluster integral for the pion gas is calculated in quantum
mechanical approach with account for both attractive and hard-core repulsive
interactions. It is shown that, in the second cluster approximation, the
repulsive pion-pion-interactions as well as the finite width of resonances give
important but almost canceling contributions. In contrast, an appreciable
deviation from the ideal gas of pions and pion resonances is observed beyond
the second cluster approximation in the framework of the Van der Waals
excluded-volume model.

</DOC>
<DOC>
<DOCNO> 40574 </DOCNO>
First Observation of the decay KL -> pi0 e e gamma


  We report on the first observation of the decay KL -> pi0 ee gamma by the
KTeV E799 experiment at Fermilab. Based upon a sample of 48 events with an
estimated background of 3.6 +/- 1.1 events, we measure the KL -> pi0 ee gamma
branching ratio to be (2.34 +/- 0.35 +/- 0.13)x10^{-8}. Our data agree with
recent O(p^6) calculations in chiral perturbation theory that include
contributions from vector meson exchange through the parameter a_V. A fit was
made to the KL -> pi0 ee gamma data for a_V with the result -0.67 +/- 0.21 +/-
0.12, which is consistent with previous results from KTeV.

</DOC>
<DOC>
<DOCNO> 8907 </DOCNO>
Collective and independent-particle motion in two-electron artificial


  Investigations of the exactly solvable excitation spectra of two-electron
quantum dots with a parabolic confinement, for different values of the
parameter R_W expressing the relative magnitudes of the interelectron repulsion
and the zero-point kinetic energy of the confined electrons, reveal for large
R_W a remarkably well-developed ro-vibrational spectrum associated with
formation of a linear trimeric rigid molecule composed of the two electrons and
the infinitely heavy confining dot. This spectrum transforms to one
characteristic of a "floppy" molecule for smaller values of R_W. The
conditional probability distribution calculated for the exact two-electron wave
functions allows for the identification of the ro-vibrational excitations as
rotations and stretching/bending vibrations, and provides direct evidence
pertaining to the formation of such molecules.

</DOC>
<DOC>
<DOCNO> 9135 </DOCNO>
Topological and energetic factors: what determines the structural


  Recent experimental results suggest that the native fold, or topology, plays
a primary role in determining the structure of the transition state ensemble,
at least for small fast folding proteins. To investigate the extent of the
topological control of the folding process, we study the folding of simplified
models of five small globular proteins constructed using a Go-like potential in
order to retain the information about the native structures but drastically
reduce the energetic frustration and energetic heterogeneity among
residue-residue native interactions. By comparing the structure of the
transition state ensemble experimentally determined by Phi-values and of the
intermediates with the ones obtained using our models, we show that these
energetically unfrustrated models can reproduce the global experimentally known
features of the transition state ensembles and "on-route" intermediates, at
least for the analyzed proteins. This result clearly indicates that, as long as
the protein sequence is sufficiently minimally frustrated, topology plays a
central role in determining the folding mechanism.

</DOC>
<DOC>
<DOCNO> 118316 </DOCNO>
The RR Lyrae U Com as a test for nonlinear pulsation models


  We use high precision multiband photometric data of the first overtone RR
Lyrae U Com to investigate the predictive capability of full amplitude,
nonlinear, convective hydrodynamical models. The main outcome of this
investigation is that theoretical predictions properly account for the
luminosity variations along a full pulsation cycle. Moreover, we find that this
approach, due to the strong dependence of this observable and of the pulsation
period on stellar parameters, supply tight constraints on stellar mass,
effective temperature, and distance modulus. Pulsational estimates of these
parameters appear in good agreement with empirical ones. Finally, the
occurrence of a well-defined bump just before the luminosity maximum gave the
unique opportunity to calibrate the turbulent convection model adopted for
handling the coupling between pulsation and convection.

</DOC>
<DOC>
<DOCNO> 170656 </DOCNO>
Competition-induced shifts of spectral peaks in photon coincidence


  We show that shifts in locations of two-photon coincidence spectral peaks,
for a bichromatically-driven two-level atom passing through a single-mode
cavity, are due to competition between excitation pathways for a
Jaynes-Cummings system. We also discuss an analogous shift of (single-photon)
spectral peaks for a driven three-level V-system, which demonstrates that
competition between excitation pathways is also important in this simple
system.

</DOC>
<DOC>
<DOCNO> 7618 </DOCNO>
Colossal electroresistance and electronic phase separation in


  The sensitivity of transport in CMR manganite to external fields is examined
using a PZT-based field effect configuration with a La0.7Ca0.3MnO3 channel
subjected to electric and magnetic fields, separately and in conjugation. We
not only find a colossal electroresistance (CER) of ~76% at 4X10^5 V/cm, but
also a remarkable complimentarity of this CER with the widely studied CMR.
Specifically, the ERmax (MRmax) of the system is largely independent of the
magnetic (electric) field biasing, and for equal conductivity values, the ER
(MR) is lower (higher) for T<Tp than that for T>Tp. The size and systematics of
the effect strongly favor a percolative phase separation picture.

</DOC>
<DOC>
<DOCNO> 10328 </DOCNO>
Iordanskii and Lifshitz-Pitaevskii Forces in the Two-Fluid Model


  It has been known since the pioneering work of Onsager and Feynman that the
statistical mechanics and dynamics of vortices play an essential role in the
behavior of superfluids and superconductors. However, the theory of vortices in
quantum fluids remains in a most unsatisfactory state, with many conflicting
results in the literature. In this paper we review the theory of Thouless, Ao
and Niu, which gives an expression for the total transverse force acting on a
quantized vortex that is in apparent disagreement with the work of Iordanskii
and of Lifshitz and Pitaevskii. In particular, no transverse force proportional
to the asymptotic normal fluid velocity was found. We use two-fluid
hydrodynamics to study this discrepancy.

</DOC>
<DOC>
<DOCNO> 100558 </DOCNO>
Curvature and Smooth Topology in Dimension Four


  Seiberg-Witten theory leads to a delicate interplay between Riemannian
geometry and smooth topology in dimension four. In particular, the scalar
curvature of any metric must satisfy certain non-trivial estimates if the
manifold in question has a non-trivial Seiberg-Witten invariant. However, it
has recently been discovered that similar statements also apply to other parts
of the curvature tensor. This article presents the most salient aspects of
these curvature estimates in a self-contained manner, and shows how they can be
applied to the theory of Einstein manifolds.
 We then probe the issue of whether the known estimates are optimal by relating
this question to a certain conjecture in Kaehler geometry.

</DOC>
<DOC>
<DOCNO> 99325 </DOCNO>
Solving second order equations by extending the PS method


  An extension of the ideas of the Prelle-Singer procedure to second order
differential equations is proposed. As in the original PS procedure, this
version of our method deals with differential equations of the form
y''={M(x,y,y')}/{N(x,y,y')}, where M and N are polynomials with coefficients in
the field of complex numbers C. The key to our approach is to focus not on the
final solution but on the first-order invariants of the equation. Our method is
an attempt to address algorithmically the solution of SOODEs whose first
integrals are elementary functions of x, y and y'.

</DOC>
<DOC>
<DOCNO> 68293 </DOCNO>
TeV scale gravity, mirror universe, and ... dinosaurs


  This is somewhat extended version of the talk given at the Gran Sasso Summer
Institute: Massive Neutrinos in Physics and Astrophysics. It describes general
ideas about mirror world, extra spatial dimensions and dinosaur extinction.
Some suggestions are made how these seemingly different things can be related
to each other.

</DOC>
<DOC>
<DOCNO> 70353 </DOCNO>
Leptoquark Pair Production in \gamma\gamma Scattering: Threshold


  The possibilities to pair-produce leptoquarks in photon-photon collisions are
discussed. QCD threshold corrections lead to a strong enhancement of the
production cross section. Suitably long-lived leptoquarks ($\Gamma_\Phi \lsim
100 \MeV$) may form Leptoquarkonium states.

</DOC>
<DOC>
<DOCNO> 7924 </DOCNO>
Off-diagonal disorder in the Anderson model of localization


  We examine the localization properties of the Anderson Hamiltonian with
additional off-diagonal disorder using the transfer-matrix method and
finite-size scaling. We compute the localization lengths and study the
metal-insulator transition (MIT) as a function of diagonal disorder, as well as
its energy dependence. Furthermore we investigate the different influence of
odd and even system sizes on the localization properties in quasi
one-dimensional systems. Applying the finite-size scaling approach in
conjunction with a nonlinear fitting procedure yields the critical parameters
of the MIT. In three dimensions, we find that the resulting critical exponent
of the localization length agrees with the exponent for the Anderson model with
pure diagonal disorder.

</DOC>
<DOC>
<DOCNO> 69494 </DOCNO>
Restrictions on neutrino oscillations from BBN. Non-resonant case


  New nucleosynthesis bounds on the oscillation parameters of active neutrinos
mixed with a sterile one are derived for the non-resonant case. The controversy
in the literature whether to use the annihilation rate or the total reaction
rate for the estimates of sterile neutrino production is resolved in favor of
the annihilation rate. In contrast to previous papers, the restrictions on
oscillations of electronic neutrinos are weaker than those of muonic and
tauonic ones.

</DOC>
<DOC>
<DOCNO> 83131 </DOCNO>
QUIP - A Tool for Computing Nonmonotonic Reasoning Tasks


  In this paper, we outline the prototype of an automated inference tool,
called QUIP, which provides a uniform implementation for several nonmonotonic
reasoning formalisms. The theoretical basis of QUIP is derived from well-known
results about the computational complexity of nonmonotonic logics and exploits
a representation of the different reasoning tasks in terms of quantified
boolean formulae.

</DOC>
<DOC>
<DOCNO> 118058 </DOCNO>
Detection of correlated galaxy ellipticities on CFHT data: first


  We report the detection of a significant (5.5 sigma) excess of correlations
between galaxy ellipticities at scales ranging from 0.5 to 3.5 arc-minutes.
This detection of a gravitational lensing signal by large-scale structure was
made using a composite high quality imaging survey of 6300 arcmin^2 obtained at
the Canada France Hawaii Telescope (CFHT) with the UH8K and CFH12K panoramic
CCD cameras. The amplitude of the excess correlation is 2.2\pm 0.2 % at 1
arcmin scale, in agreement with theoretical predictions of the lensing effect
induced by large-scale structure.We provide a quantitative analysis of
systematics which could contribute to the signal and show that the net effect
is small and can be corrected for. We show that the measured ellipticity
correlations behave as expected for a gravitational shear signal. The
relatively small size of our survey precludes tight constraints on cosmological
models. However the data are in favor of cluster normalized cosmological
models, and marginally reject Cold Dark Matter models with (Omega=0.3,
sigma_8<0.6) or (Omega=1, sigma_8=1). The detection of cosmic shear
demonstrates the technical feasibility of using weak lensing surveys to measure
dark matter clustering and the potential for cosmological parameter
measurements, in particular with upcoming wide field CCD cameras.

</DOC>
<DOC>
<DOCNO> 100479 </DOCNO>
Exercises in exact quantization


  The formalism of exact 1D quantization is reviewed in detail and applied to
the spectral study of three concrete Schr\"odinger Hamiltonians $[-\d^2/\d q^2
+ V(q)]^\pm$ on the half-line $\{q>0\}$, with a Dirichlet (-) or Neumann (+)
condition at q=0. Emphasis is put on the analytical investigation of the
spectral determinants and spectral zeta functions with respect to singular
perturbation parameters. We first discuss the homogeneous potential $V(q)=q^N$
as $N \to +\infty$vs its (solvable) $N=\infty$ limit (an infinite square well):
useful distinctions are established between regular and singular behaviours of
spectral quantities; various identities among the square-well spectral
functions are unraveled as limits of finite-N properties. The second model is
the quartic anharmonic oscillator: its zero-energy spectral determinants
$\det(-\d^2/\d q^2 + q^4 + v q^2)^\pm$ are explicitly analyzed in detail,
revealing many special values, algebraic identities between Taylor
coefficients, and functional equations of a quartic type coupled to asymptotic
$v \to +\infty$ properties of Airy type. The third study addresses the
potentials $V(q)=q^N+v q^{N/2-1}$ of even degree: their zero-energy spectral
determinants prove computable in closed form, and the generalized eigenvalue
problems with v as spectral variable admit exact quantization formulae which
are perfect extensions of the harmonic oscillator case (corresponding to N=2);
these results probably reflect the presence of quasi-exactly solvable
potentials in the family above.

</DOC>
<DOC>
<DOCNO> 100468 </DOCNO>
A generalization of Kummer's identity


  The well-known Kummer's formula evaluates the hypergeometric series
2F1(A,B;C;-1) when the relation B-A+C=1 holds. This paper deals with evaluation
of 2F1(-1) series in the case when C-A+B is an integer. Such a series is
expressed as a sum of two \Gamma-terms multiplied by terminating 3F2(1) series.
A few such formulas were essentially known to Whipple in 1920's. Here we give a
simpler and more complete overview of this type of evaluations. Additionally,
algorithmic aspects of evaluating hypergeometric series are considered. We
illustrate Zeilberger's method and discuss its applicability to non-terminating
series, and present a couple of similar generalizations of other known
formulas.

</DOC>
<DOC>
<DOCNO> 11214 </DOCNO>
Dynamics of two colliding Bose-Einstein condensates in an elongated


  We study the dynamics of two interacting Bose-Einstein condensates, by
numerically solving two coupled Gross-Pitaevskii equations at zero temperature.
We consider the case of a sudden transfer of atoms between two trapped states
with different magnetic moments: the two condensates are initially created with
the same density profile, but are trapped into different magnetic potentials,
whose minima are vertically displaced by a distance much larger than the
initial size of both condensates. Then the two condensates begin to perform
collective oscillations, undergoing a complex evolution, characterized by
collisions between the two condensates. We investigate the effects of their
mutual interaction on the center-of-mass oscillations and on the time evolution
of the aspect ratios. Our theoretical analysis provides a useful insight into
the recent experimental observations by Maddaloni et al., cond-mat/0003402.

</DOC>
<DOC>
<DOCNO> 40664 </DOCNO>
Bounds on Universal Extra Dimensions


  We show that the bound from the electroweak data on the size of extra
dimensions accessible to all the standard model fields is rather loose. These
"universal" extra dimensions could have a compactification scale as low as 300
GeV for one extra dimension. This is because the Kaluza-Klein number is
conserved and thus the contributions to the electroweak observables arise only
from loops. The main constraint comes from weak-isospin violation effects. We
also compute the contributions to the S parameter and the $Zb\bar{b}$ vertex.
The direct bound on the compactification scale is set by CDF and D0 in the few
hundred GeV range, and the Run II of the Tevatron will either discover extra
dimensions or else it could significantly raise the bound on the
compactification scale. In the case of two universal extra dimensions, the
current lower bound on the compactification scale depends logarithmically on
the ultra-violet cutoff of the higher dimensional theory, but can be estimated
to lie between 400 and 800 GeV. With three or more extra dimensions, the cutoff
dependence may be too strong to allow an estimate.

</DOC>
<DOC>
<DOCNO> 13082 </DOCNO>
Two-channel Kondo Lattice Model on a ladder studied by the Density


  Using the density matrix renormalization group (DMRG) method we study a
two-channel Kondo lattice model on a half filled ladder. Our model involves an
on-site s-wave and a nearest neighbor d-wave coupling between the local moments
and the conduction electrons on the ladder. By changing the relative strength
of the two Kondo interactions we examine the evolution of the system from a
conventional Kondo insulator with a singlet at each site to a new kind of
semimetallic state formed by overlapping of Zhang-Rice-like singlets. The DMRG
is used to study how the spin and charge correlation functions evolve between
these two regimes.

</DOC>
<DOC>
<DOCNO> 122322 </DOCNO>
CMB Analysis of Boomerang & Maxima & the Cosmic Parameters


  We show how estimates of parameters characterizing inflation-based theories
of structure formation localized over the past year when large scale structure
(LSS) information from galaxy and cluster surveys was combined with the rapidly
developing cosmic microwave background (CMB) data, especially from the recent
Boomerang and Maxima balloon experiments. All current CMB data plus a
relatively weak prior probability on the Hubble constant, age and LSS points to
little mean curvature (Omega_{tot} = 1.08\pm 0.06) and nearly scale invariant
initial fluctuations (n_s =1.03\pm 0.08), both predictions of (non-baroque)
inflation theory. We emphasize the role that degeneracy among parameters in the
L_{pk} = 212\pm 7 position of the (first acoustic) peak plays in defining the
$\Omega_{tot}$ range upon marginalization over other variables. Though the CDM
density is in the expected range (\Omega_{cdm}h^2=0.17\pm 0.02), the baryon
density Omega_bh^2=0.030\pm 0.005 is somewhat above the independent 0.019\pm
0.002 nucleosynthesis estimate. CMB+LSS gives independent evidence for dark
energy (Omega_\Lambda=0.66\pm 0.06) at the same level as from supernova (SN1)
observations, with a phenomenological quintessence equation of state limited by
SN1+CMB+LSS to w_Q<-0.7 cf. the w_Q=-1 cosmological constant case.

</DOC>
<DOC>
<DOCNO> 13143 </DOCNO>
Magnetization in Molecular Iron Rings


  The organometallic ring molecules Fe_6 and Fe_10 are leading examples of a
class of nanoscopic molecular magnets, which have been of intense recent
interest both for their intrinsic magnetic properties and as candidates for the
observation of macroscopic quantum coherent phenomena. Torque magnetometry
experiments have been performed to measure the magnetization in single crystals
of both systems. We provide a detailed interpretation of these results, with a
view to full characterization of the material parameters. We present both the
most accurate numerical simulations performed to date for ring molecules, using
Exact Diagonalization and Density Matrix Renormalization Group techniques, and
a semiclassical description for purposes of comparison. The results permit
quantitative analysis of the variation of critical fields with angle, of the
nature and height of magnetization and torque steps, and of the width and
rounding of the plateau regions in both quantities.

</DOC>
<DOC>
<DOCNO> 84420 </DOCNO>
Singularity structure of the two point function of the free Dirac field


  We give an introduction to the techniques from microlocal analysis that have
successfully been applied in the investigation of Hadamard states of free
quantum field theories on curved spacetimes. The calculation of the wave front
set of the two point function of the free Klein-Gordon field in a Hadamard
state is reviewed, and the polarization set of a Hadamard two point function of
the free Dirac field on a curved spacetime is calculated.

</DOC>
<DOC>
<DOCNO> 71212 </DOCNO>
Combinatorics of (perturbative) quantum field theory


  We review the structures imposed on perturbative QFT by the fact that its
Feynman diagrams provide Hopf and Lie algebras. We emphasize the role which the
Hopf algebra plays in renormalization by providing the forest formulas. We
exhibit how the associated Lie algebra originates from an operadic operation of
graph insertions. Particular emphasis is given to the connection with the
Riemann--Hilbert problem. Finally, we outline how these structures relate to
the numbers which we see in Feynman diagrams.

</DOC>
<DOC>
<DOCNO> 118974 </DOCNO>
The Instability Strip of M3


  We present new multicolour CCD photometry of the central part of the globular
cluster M3, mapping the precise position of ~120 RR Lyrae stars (RRab, RRd,
RRc) on the horizontal branch (HB). The location of the double-mode variables
(RRd) is in perfect agreement with recent theoretical results. We find a
significant internal spread of metallicity amongst the RRab variables.

</DOC>
<DOC>
<DOCNO> 117777 </DOCNO>
Faint Infrared Flares from the Microquasar GRS 1915+105


  We present simultaneous infrared and X-ray observations of the Galactic
microquasar GRS 1915+105 using the Palomar 5-m telescope and Rossi X-ray Timing
Explorer on July 10, 1998 UT. Over the course of 5 hours, we observed 6 faint
infrared (IR) flares with peak amplitudes of $\sim 0.3-0.6 $ mJy and durations
of $\sim 500-600 $ seconds. These flares are associated with X-ray
soft-dip/soft-flare cycles, as opposed to the brighter IR flares associated
with X-ray hard-dip/soft-flare cycles seen in August 1997 by Eikenberry et al.
(1998). Interestingly, the IR flares begin {\it before} the X-ray oscillations,
implying an ``outside-in'' origin of the IR/X-ray cycle. We also show that the
quasi-steady IR excess in August 1997 is due to the pile-up of similar faint
flares. We discuss the implications of this flaring behavior for understanding
jet formation in microquasars.

</DOC>
<DOC>
<DOCNO> 68333 </DOCNO>
The Cosmological Constant From The Viewpoint Of String Theory


  The mystery of the cosmological constant is probably the most pressing
obstacle to significantly improving the models of elementary particle physics
derived from string theory. The problem arises because in the standard
framework of low energy physics, there appears to be no natural explanation for
vanishing or extreme smallness of the vacuum energy, while on the other hand it
is very difficult to modify this framework in a sensible way. In seeking to
resolve this problem, one naturally wonders if the real world can somehow be
interpreted in terms of a vacuum state with unbroken supersymmetry.

</DOC>
<DOC>
<DOCNO> 99715 </DOCNO>
Spectral Properties of Random Non-self-adjoint Matrices and Operators


  We describe some numerical experiments which determine the degree of spectral
instability of medium size randomly generated matrices which are far from
self-adjoint. The conclusion is that the eigenvalues are likely to be
intrinsically uncomputable for similar matrices of a larger size. We also
describe a stochastic family of bounded operators in infinite dimensions for
almost all of which the eigenvectors generate a dense linear subspace, but the
eigenvalues do not determine the spectrum. Our results imply that the spectrum
of the non-self-adjoint Anderson model changes suddenly as one passes to the
infinite volume limit.

</DOC>
<DOC>
<DOCNO> 72015 </DOCNO>
Search for QGP and Thermal Freeze-out of Strange Hadrons


  After reviewing the observables of QGP we perform an analysis of m_T spectra
of strange hadrons measured as function of centrality in 156AGeV Pb--Pb
interactions. We show that there is a good agreement between the chemical and
thermal freeze-out conditions, providing additional evidence for the formation
and sudden disintegration of a supercooled QGP fireball.

</DOC>
<DOC>
<DOCNO> 150884 </DOCNO>
Restrictions on Gauge Groups in Noncommutative Gauge Theory


  We show that the gauge groups SU(N), SO(N) and Sp(N) cannot be realized on a
flat noncommutative manifold, while it is possible for U(N).

</DOC>
<DOC>
<DOCNO> 10469 </DOCNO>
A Consistent Treatment of Strong Coupling in Disordered Superconducting


  We develop a consistent treatment of disorder effects in strong coupling
superconductors. We use two different approaches, starting either from above or
below the transition temperature, and show their equivalence. The normal state
approach is a natural extension of a recently developed non-perturbative
resummation technique. For the superconducting state we extend the standard
Eliashberg theory to include disorder effects. We obtain a compact set of
equations which are physically transparent and easy to use. They correctly
reproduce the usual strong coupling results and disordered perturbation theory
results in the appropriate limits. We numerically solve these equations to
obtain transition temperature as a function of disorder for different phonon
couplings.

</DOC>
<DOC>
<DOCNO> 84377 </DOCNO>
Naked Singularities in the Charged Vaidya-deSitter Spacetime


  We study the occurrence of naked singularities in the spherically symmetric
collapse of a charged null fluid in an expanding deSitter background - a piece
of charged Vaidya-deSitter spacetime. The necessary conditions for the
formation of a naked singularity are found. The results for the uncharged
solutions can be recovered from our analysis.

</DOC>
<DOC>
<DOCNO> 116460 </DOCNO>
Hierarchic Theory of Condensed Matter: Long relaxation, macroscopic


  1. Theoretical background for macroscopic oscillations in condensed matter;
2. The hypothesis of [entropy - mass - time] interrelation; 3. The entropy -
information content of matter as a hierarchic system; 4. Experimentally
revealed macroscopic oscillations; 5. Phenomena in water and aqueous systems,
induced by magnetic field: Coherent radio-frequency oscillations in water,
revealed by C. Smith; 6. Influence of weak magnetic field on the properties of
solid bodies; 7. Possible mechanism of perturbations of nonmagnetic materials
under magnetic treatment.

</DOC>
<DOC>
<DOCNO> 39916 </DOCNO>
Measurement of the product branching fraction


  Based on an a high statistics e+e- -> ccbar data sample, we report on the
inclusive rate for charmed baryons to decay into / particles using charm-event
tagging. We select e+e- -> ccbar events which have a clear anti-charm tag and
measure the / content in the hemisphere opposite the tag (charge conjugate
modes are implicit). This allows us to determine the product branching
fraction: B(/)=B(c->Theta_c)*B(Theta_c->/\X), where Theta_c represents a sum
over all charmed baryons produced in e+e- fragmentation at sqrt(s)=10.5 GeV,
given our specific tags. We obtain B(/)=(1.87+/-0.03+/-0.33)%

</DOC>
<DOC>
<DOCNO> 151630 </DOCNO>
Towards the large N limit of pure N=1 super Yang Mills


  We find the gravity solution corresponding to a large number of NS or D
fivebranes wrapped on a two sphere so that we have pure ${\cal N}=1$ super
Yang-Mills in the IR. The supergravity solution is smooth, it shows confinement
and it breaks the $U(1)_R$ chiral symmetry in the appropriate way. When the
gravity approximation is valid the masses of glueballs are comparable to the
masses of Kaluza Klein states on the fivebrane, but if we could quantize
strings on this background it looks like we should be able to decouple the KK
states.

</DOC>
<DOC>
<DOCNO> 8323 </DOCNO>
Some properties of eigenvalues and eigenfunctions of the cubic


  Comparison between the exact value of the spectral zeta function,
$Z_{H}(1)=5^{-6/5}[3-2\cos(\pi/5)]\Gamma^2(1/5)/\Gamma(3/5)$, and the results
of numeric and WKB calculations supports the conjecture by Bessis that all the
eigenvalues of this PT-invariant hamiltonian are real. For one-dimensional
Schr\"odinger operators with complex potentials having a monotonic imaginary
part, the eigenfunctions (and the imaginary parts of their logarithmic
derivatives) have no real zeros.

</DOC>
<DOC>
<DOCNO> 70891 </DOCNO>
Chargino Production and Decay in Photon-Photon-Collisions


  We study the production and leptonic decay of charginos in collisions of
polarized photon beams including the complete spin correlations. The photons
can be generated by Compton backscattering of polarized laser pulses off a
polarized electron beam. Since the production process is determined alone by
the electromagnetic coupling of the charginos this process allows to study
their decay dynamics. The cross section and the forward-backward asymmetry of
the decay lepton are very sensitive to the gaugino mass parameter $M_1$ and to
the sneutrino mass without any ambiguities.

</DOC>
<DOC>
<DOCNO> 101521 </DOCNO>
Immersions of surfaces in almost complex 4-manifolds


  In this note, we investigate the relation between double points and complex
points of immersed surfaces in almost-complex 4-manifolds and show how
estimates for the minimal genus of embedded surfaces lead to inequalities
between the number of double points and the number of complex points of an
immersion. We also provide a generalization of a classical genus estimate due
to V.A. Rokhlin to the case of immersed surfaces.

</DOC>
<DOC>
<DOCNO> 101047 </DOCNO>
Solutions of DEs and PDEs as Potential Maps Using First Order


  Using parametrized curves (Section 1) or parametrized sheets (Section 3), and
suitable metrics, we treat the jet bundle of order one as a semi-Riemann
manifold. This point of view allows the description of solutions of DEs as
pregeodesics (Section 1) and the solutions of PDEs as potential maps (Section
3), via Lagrangians of order one or via generalized Lorentz world-force laws.
Implicitly, we solved a problem rised first by Poincar\'e: find a suitable
geometric structure that converts the trajectories of a given vector field into
geodesics (see also [6] - [11]). Section 2 and Section 3 realize the passage
from the Lagrangian dynamics to the covariant Hamilton equations.

</DOC>
<DOC>
<DOCNO> 120222 </DOCNO>
Quasar Variability in the Framework of Poissonian Models


  In this paper we review the basic Poissonian formulation of quasar
variability, using it as a mathematical tool to extract relevant parameters
such as the energy, rate and lifetimes of the flares through the analysis of
observed light curves. It is shown that in this very general framework the well
established anti-correlation between variability amplitude and wavelength can
only be understood as an effect of an underlying spectral component which
remains stable on long time-scales, and is redder than the variable component.
The formalism is applied to the B and R light curves of 42 PG quasars collected
by the Wise Observatory group. Variability indices for these data are obtained
with a Structure Function analysis. The mean number of living flares is
constrained to be in the range between 5 and 100, while their rates are found
to be of order 1--100 per yr. Monochromatic optical flare energies of
10^{46-48} erg/A and life-times of 0.5 to 3 yr are derived. Lower limits of
typically 25% are established for the contribution of a non-variable component
in the R band. The substantial diversity in these properties among quasars
invalidates simple versions of the Poissonian model in which flare energies,
lifetimes and the background contribution are treated as universal invariants.
The good correlation between the EW(H_beta) and the long term variability
amplitude is interpreted in a scenario where only the variable component
participates in the ionization of the line emitting gas. This idea is
consistent with the observed trends of the variability amplitude with lambda,
EW(HeII) and the X-ray to optical spectral index (abridged).

</DOC>
<DOC>
<DOCNO> 12337 </DOCNO>
Observation of anomalous single-magnon scattering in half-metallic


  Temperature variation of resistivity and specific heat have been measured for
prototypical half-metallic ferromagnets,
 R_0.6Sr_0.4MnO_3, with controlling the one-electron bandwidth W. We have found
variation of the temperature scalings in the resistivity from
 T^2 (R = La, and Nd) to T^3 (R = Sm), and have interpreted the $T^3-law in
terms of the anomalous single-magnon scattering (AMS) process in the
half-metallic system.

</DOC>
<DOC>
<DOCNO> 151276 </DOCNO>
Warped AdS near-horizon geometry of completely localized intersections


  We study a Hanany-Witten set-up relevant to N = 2 superconformal field
theories. We find the exact near-horizon solution for this 11-dimensional
system which involves intersecting M5-branes. The metric describes a warped
product of AdS_5 with a manifold with SU(2) x U(1) isometry.

</DOC>
<DOC>
<DOCNO> 12615 </DOCNO>
The experimental observation of Beliaev damping in a Bose condensed gas


  We report the first experimental observation of Beliaev damping of a
collective excitation in a Bose-condensed gas. Beliaev damping is not predicted
by the Gross-Pitaevskii equation and so this is one of the few experiments that
tests BEC theory beyond the mean field approximation. Measurements of the
amplitude of a high frequency scissors mode, show that the Beliaev process
transfers energy to a lower lying mode and then back and forth between these
modes. These characteristics are quite distinct from those of Landau damping,
which leads to a monotonic decrease in amplitude. To enhance the Beliaev
process we adjusted the geometry of the magnetic trapping potential to give a
frequency ratio of 2 to 1 between two of the scissors modes of the condensate.
The ratios of the trap oscillation frequencies $\omega_y / \omega_x$ and
$\omega_z / \omega_x$ were changed independently, so that we could investigate
the resonant coupling over a range of conditions.

</DOC>
<DOC>
<DOCNO> 152256 </DOCNO>
Polarization Vectors, Doublet Structure and Wigner's Little Group in


  We establish the equivalence of the Maxwell-Chern-Simons-Proca model to a
doublet of Maxwell-Chern-Simons models at the level of polarization vectors of
the basic fields using both Lagrangian and Hamiltonian formalisms. The analysis
reveals a U(1) invariance of the polarization vectors in the momentum space.
Its implications are discussed. We also study the role of Wigner's little group
as a generator of gauge transformations in three space-time dimensions.

</DOC>
<DOC>
<DOCNO> 39917 </DOCNO>
A measurement of lifetime differences in the neutral D-meson system


  Using a high statistics sample of photoproduced charm particles from the
FOCUS experiment at Fermilab, we compare the lifetimes of neutral D mesons
decaying via D0 to K- pi+ and K- K+ to measure the lifetime differences between
CP even and CP odd final states. These measurements bear on the phenomenology
of D0 - D0bar mixing. If the D0 to K-pi+ is an equal mixture of CP even and CP
odd eigenstates, we measure yCP = 0.0342 \pm 0.0139 \pm 0.0074.

</DOC>
<DOC>
<DOCNO> 9350 </DOCNO>
Weakly-interacting Bose-Einstein condensates under rotation


  We investigate the ground and low excited states of a rotating, weakly
interacting Bose-Einstein condensed gas in a harmonic trap for a given angular
momentum. Analytical results in various limits, as well as numerical results
are presented, and these are compared with those of previous studies. Within
the mean-field approximation and for repulsive interaction between the atoms,
we find that for very low values of the total angular momentum per particle,
$L/N \to 0$, where $L \hbar$ is the angular momentum and $N$ is the total
number of particles, the angular momentum is carried by quadrupolar ($|m| = 2$)
surface modes. For $L/N =1$ a vortex-like state is formed and all the atoms
occupy the $m=1$ state. For small negative values of $L/N-1$ the states with
$m=0$ and $m=2$ become populated, and for small positive values of $L/N-1$
atoms in the states with $m=5$ and $m=6$ carry the additional angular momentum.
In the whole region $0 \le L/N \le 1$ we have strong analytic and numerical
evidence that the interaction energy drops linearly as a function of $L/N$. We
have also found that an array of singly quantized vortices is formed as $L/N$
increases. Finally we have gone beyond the mean-field approximation and have
calculated the energy of the lowest state up to order $N$ for small negative
values of $L/N-1$, as well as the energy of the low-lying excited states.

</DOC>
<DOC>
<DOCNO> 99878 </DOCNO>
Some Special Geometry in Dimension Six


  We generalise the notion of contact manifold by allowing the contact
distribution to have codimension two. There are special features in dimension
six. In particular, we show that the complex structure on a three-dimensional
complex contact manifold is determined solely by the underlying contact
distribution.

</DOC>
<DOC>
<DOCNO> 84277 </DOCNO>
Conformal invariance and particle aspects in general relativity


  We study the breakdown of conformal symmetry in a conformally invariant
gravitational model. The symmetry breaking is introduced by defining a
preferred conformal frame in terms of the large scale characteristics of the
universe. In this context we show that a local change of the preferred
conformal frame results in a Hamilton-Jacobi equation describing a particle
with adjustable mass. In this equation the dynamical characteristics of the
particle substantially depends on the applied conformal factor and local
geometry. Relevant interpretations of the results are also discussed.

</DOC>
<DOC>
<DOCNO> 101709 </DOCNO>
Polynomial Algebras on Coadjoint Orbits of Semisimple Lie Groups


  We study the algebraic structure of the Poisson algebra P(O) of polynomials
on a coadjoint orbit O of a semisimple Lie algebra. We prove that P(O) splits
into a direct sum of its center and its derived ideal. We also show that P(O)
is simple as a Poisson algebra iff O is semisimple.

</DOC>
<DOC>
<DOCNO> 7917 </DOCNO>
Defect fugacity, Spinwave Stiffness and T_c of the 2-d Planar Rotor


  We obtain precise values for the fugacities of vortices in the 2-d planar
rotor model from Monte Carlo simulations in the sector with {\em no} vortices.
The bare spinwave stiffness is also calculated and shown to have significant
anharmonicity. Using these as inputs in the KT recursion relations, we predict
the temperature T_c = 0.925, using linearised equations, and $T_c = 0.899 \pm
>.005$ using next higher order corrections, at which vortex unbinding commences
in the unconstrained system. The latter value, being in excellent agreement
with all recent determinations of T_c, demonstrates that our method 1)
constitutes a stringent measure of the relevance of higher order terms in KT
theory and 2) can be used to obtain transition temperatures in similar systems
with modest computational effort.

</DOC>
<DOC>
<DOCNO> 116507 </DOCNO>
Structures and Stabilities of CaO and MgO Clusters and Cluster Ions: An


  The structures and relative stabilities of doubly-charged nonstoichiometric
(CaO)$_n$Ca$^{2+}$ (n=1--29) cluster ions and of neutral stoichiometric
(MgO)$_n$ and (CaO)$_n$ (n=3,6,9,12,15,18) clusters are studied through {\em ab
initio} Perturbed Ion plus polarization calculations. The large
coordination-dependent polarizabilities of oxide anions favor the formation of
surface sites, making the critical cluster size where anions with bulk
coordination first appear larger than that found in the related case of alkali
halides. Thus, we show that there are substantial structural differences
between alkali halide and alkaline-earth oxide cluster ions, contrary to what
is suggested by the similarities in the experimental mass spectra. An
alternative interpretation of the magic numbers for the case of oxides is
proposed, which involves an explicit consideration of isomer structures
different from the ground states. A comparison with the previously studied
(MgO)$_n$Mg$^{2+}$ cluster ions shows that the emergence of bulklike structural
properties with size is slower for calcium oxide. Nevertheless, the structures
of the doubly charged clusters are rather similar for the two materials. On the
contrary, the study of the neutrals reveals interesting structural differences
between MgO and CaO, similar to those found in the case of alkali halides.

</DOC>
<DOC>
<DOCNO> 151708 </DOCNO>
Construction and analysis of anomaly-free supersymmetric SO(2N)/U(N)


  This paper discusses a procedure for the consistent coupling of gauge- and
matter superfields to supersymmetric sigma-models on symmetric coset spaces of
Kaehler type. We exhibit the finite isometry transformations and the
corresponding Kaehler transformations. These lead to the construction of a
generalized type of Killing potentials. In certain cases a charge quantization
condition needs to be imposed to guarantee the global existence of a line
bundle on a coset space. The results are applied to the explicit construction
of sigma-models on cosets SO(2N)/U(N). Only a finite number of these models can
consistently incorporate matter in representations descending from the
spinorial representations of SO(2N). We investigate in detail some aspects of
the vacuum structure of the gauged SO(10)/U(5) theory, with surprising results:
the fully gauged minimal anomaly-free model is shown be singular, as the
kinetic terms of the quasi-Goldstone fermions vanish in the vacuum. Gauging
only the linear isometry group SU(5)xU(1), or one of its subgroups, can give a
physically well-behaved theory. With gauged U(1) this requires the
Fayet-Iliopoulos term to take values in a specific limited range.

</DOC>
<DOC>
<DOCNO> 10713 </DOCNO>
Adjusting the melting point of a model system via Gibbs-Duhem


  Model interaction potentials for real materials are generally optimized with
respect to only those experimental properties that are easily evaluated as
mechanical averages (e.g., elastic constants (at T=0 K), static lattice
energies and liquid structure). For such potentials, agreement with experiment
for the non-mechanical properties, such as the melting point, is not guaranteed
and such values can deviate significantly from experiment. We present a method
for re-parameterizing any model interaction potential of a real material to
adjust its melting temperature to a value that is closer to its experimental
melting temperature. This is done without significantly affecting the
mechanical properties for which the potential was modeled. This method is an
application of Gibbs-Duhem integration [D. Kofke, Mol. Phys.78, 1331 (1993)].
As a test we apply the method to an embedded atom model of aluminum [J. Mei and
J.W. Davenport, Phys. Rev. B 46, 21 (1992)] for which the melting temperature
for the thermodynamic limit is 826.4 +/- 1.3K - somewhat below the experimental
value of 933K. After re-parameterization, the melting temperature of the
modified potential is found to be 931.5K +/- 1.5K.

</DOC>
<DOC>
<DOCNO> 121202 </DOCNO>
The Formation of the Milky Way Disk


  We present theoretical results on the galactic abundance gradients of several
chemical species for the Milky Way disk, obtained using an improved version of
the two-infall model of Chiappini, Matteucci, & Gratton (1997) that
incorporates a more realistic model of the galactic halo and disk. This
improved model provides a satisfactory fit to the elemental abundance gradients
as inferred from the observations and also to other radial features of our
galaxy (i.e., gas, star formation rate and star density profiles). We discuss
the implications these results may have for theories of the formation of the
Milky Way and make some predictions that could in principle be tested by future
observations.

</DOC>
<DOC>
<DOCNO> 102458 </DOCNO>
Arnold conjecture and an explicit isomorphism between Floer homology and


  We use Liu-Tian's virtual moduli cycle methods to construct detailedly the
explicit isomorphism between Floer homology and quantum homology for any closed
symplectic manifold that was first outlined by Piunikhin, Salamon and Schwarz
for the case of the semi-positive symplectic manifolds. As a consequence the
Arnold conjecture is proved again.

</DOC>
<DOC>
<DOCNO> 170207 </DOCNO>
Loading a continuous-wave atom laser by optical pumping techniques


  Demonstrating that despite loss processes, Bose-Einstein condensates can be
formed in steady state is a prerequisite for obtaining a coherent beam of atoms
in a continuous-wave atom laser. In this paper we propose a method for loading
atoms into the thermal component of a Bose condensed cloud confined in a
magnetic trap. This method is aimed at allowing steady state dynamics to be
achieved. The proposed scheme involves loading atoms into the conservative
magnetic potential using the spontaneous emission of photons. We show that the
probability for the reabsorption of these photons may be small .

</DOC>
<DOC>
<DOCNO> 71402 </DOCNO>
Hadronic Correlated Flares from Mrk 501


  We discuss the possibility of explaining the extraordinary, correlated
X-ray/TeV flares observed during April 1997 from Mrk 501, by synchrotron-pair
cascades injected by synchrotron radiation from ultra-high energy protons and
muons. Evaluating the jet conditions required to explain the observed features
of the flares, the allowed region for this model in the parameter space of jet
magnetic field and Doppler factor is identified, and compared with the
parameter choices of other, both hadronic and leptonic models presented in the
literature. The present model requires magnetic fields similar to other
hadronic models for gamma-ray blazars (B >~ 30 G), but a lower Doppler factor
(D =~ 3).

</DOC>
<DOC>
<DOCNO> 118329 </DOCNO>
Theory of pixel lensing towards M31 I: the density contribution and mass


  POINT-AGAPE is an Anglo-French collaboration which is employing the Isaac
Newton Telescope (INT) to conduct a pixel-lensing survey towards M31. In this
paper we investigate what we can learn from pixel-lensing observables about the
MACHO mass and fractional contribution in M31 and the Galaxy for the case of
spherically-symmetric near-isothermal haloes. We employ detailed pixel-lensing
simulations which include many of the factors which affect the observables. For
a maximum MACHO halo we predict an event rate in V of up to 100 per season for
M31 and 40 per season for the Galaxy. However, the Einstein radius crossing
time is generally not measurable and the observed full-width half-maximum
duration provides only a weak tracer of lens mass. Nonetheless, we find that
the near-far asymmetry in the spatial distribution of M31 MACHOs provides
significant information on their mass and density contribution. We present a
likelihood estimator for measuring the fractional contribution and mass of both
M31 and Galaxy MACHOs which permits an unbiased determination to be made of
MACHO parameters, even from data-sets strongly contaminated by variable stars.
If M31 does not have a significant population of MACHOs in the mass range
0.001-1 Solar masses strong limits will result from the first season of INT
observations. Simulations based on currently favoured density and mass values
indicate that, after three seasons, the M31 MACHO parameters should be
constrained to within a factor four uncertainty in halo fraction and an order
of magnitude uncertainty in mass (90% confidence). Interesting constraints on
Galaxy MACHOs may also be possible. For a campaign lasting ten years,
comparable to the lifetime of current LMC surveys, reliable estimates of MACHO
parameters in both galaxies should be possible. (Abridged)

</DOC>
<DOC>
<DOCNO> 117755 </DOCNO>
Growth of a Vortex Mode during Gravitational Collapse Resulting in Type


  We investigate stability of a gravitationally collapsing iron core against
non-spherical perturbation. The gravitationally collapsing iron core is
approximated by a similarity solution for dynamically collapsing polytropic gas
sphere. We find that the similarity solution is unstable against non-spherical
perturbations. The perturbation grows in proportion to $ (t - t_0) ^{-\sigma} $
while the the central density increases in proportion to $ (t - t_0) ^{-2} $.
The growth rate is $ \sigma = 1/3 + \ell (\gamma - 4/3) $, where $ \gamma $ and
$ \ell $ denote the polytropic index and the parameter $ \ell $ of the
spherical harmonics, $ Y_{\ell} ^m (\theta, \phi) $, respectively. The growing
perturbation is dominated by vortex motion. Thus it excites global convection
during the collapse and may contribute to material mixing in a type II
supernova.

</DOC>
<DOC>
<DOCNO> 150399 </DOCNO>
D-branes at Singular Curves of Calabi-Yau Compactifications


  We study the Gepner model description of D-branes in Calabi-Yau manifolds
with singular curves. From a geometrical point of view, the resolution of
singularities leads to additional homology cycles around which branes can wrap.
Using techniques from conformal field theory we address the construction of
boundary states for branes wrapping additional 3-cycles on the resolved
Calabi-Yau manifold. Explicit formulas are provided for Z_2 singular curves.

</DOC>
<DOC>
<DOCNO> 122049 </DOCNO>
The First Hour of Extra-galactic Data of the Sloan Digital Sky Survey


  On 26 May 1999, one of the Sloan Digital Sky Survey (SDSS) fiber-fed
spectrographs saw astronomical first light. This was followed by the first
spectroscopic commissioning run during the dark period of June 1999. We present
here the first hour of extra-galactic spectroscopy taken during these early
commissioning stages: an observation of the Coma cluster of galaxies. Our data
samples the Southern part of this cluster, out to a radius of 1.5degrees and
thus fully covers the NGC 4839 group. We outline in this paper the main
characteristics of the SDSS spectroscopic systems and provide redshifts and
spectral classifications for 196 Coma galaxies, of which 45 redshifts are new.
For the 151 galaxies in common with the literature, we find excellent agreement
between our redshift determinations and the published values. As part of our
analysis, we have investigated four different spectral classification
algorithms: spectral line strengths, a principal component decomposition, a
wavelet analysis and the fitting of spectral synthesis models to the data. We
find that a significant fraction (25%) of our observed Coma galaxies show signs
of recent star-formation activity and that the velocity dispersion of these
active galaxies (emission-line and post-starburst galaxies) is 30% larger than
the absorption-line galaxies. We also find no active galaxies within the
central (projected) 200 h-1 Kpc of the cluster. The spatial distribution of our
Coma active galaxies is consistent with that found at higher redshift for the
CNOC1 cluster survey. Beyond the core region, the fraction of bright active
galaxies appears to rise slowly out to the virial radius and are randomly
distributed within the cluster with no apparent correlation with the potential
merger of the NGC 4839 group. [ABRIDGED]

</DOC>
<DOC>
<DOCNO> 178996 </DOCNO>
On scission configuration in ternary fission


  A static scission configuration in cold ternary fission has been considered
in the framework of two mean field approaches. The virial theorems has been
suggested to investigate correlations in the phase space, starting from a
kinetic equation. The inverse mean field method is applied to solve
single-particle Schredinger equation, instead of constrained selfconsistent
Hartree-Fock equations. It is shown, that it is possible to simulate
one-dimensional three-center system via inverse scattering method in the
approximation of reflectless single-particle potentials

</DOC>
<DOC>
<DOCNO> 170373 </DOCNO>
Quantum Complexity of Integration


  It is known that quantum computers yield a speed-up for certain discrete
problems. Here we want to know whether quantum computers are useful for
continuous problems. We study the computation of the integral of functions from
the classical Hoelder classes with d variables. The optimal orders for the
complexity of deterministic and (general) randomized methods are known. We
obtain the respective optimal orders for quantum algorithms and also for
restricted Monte Carlo (only coin tossing instead of general random numbers).
To summarize the results one can say that (1) there is an exponential speed-up
of quantum algorithms over deterministic (classical) algorithms, if the
smoothness is small; (2) there is a (roughly) quadratic speed-up of quantum
algorithms over randomized classical methods, if the smoothness is small.

</DOC>
<DOC>
<DOCNO> 102871 </DOCNO>
On von Neumann spectral triples


  We define the notion of von Neumann spectral triple and consider the
associated index problem. We compute the analytic Chern-Connes character of
such a von Neumann spectral triple and prove the corresponding local formula
for its Hochschild class. This formula involves the Dixmier trace for
$II_{\infty}$ von Neumann algebras. In the case of foliations, we identify this
Dixmier trace with the corresponding measured Wodzicki residue.

</DOC>
<DOC>
<DOCNO> 169582 </DOCNO>
Quantum key distribution relied on trusted information center


  Quantum correlation between two particles and among three particles show
nonclassic properties that can be used for providing secure transmission of
information. In this paper, we propose two quantum key distribution schemes for
quantum cryptographic network, which use the correlation properties of two and
three particles. One is implemented by the Greenberger-Horne-Zeilinger state,
and another is implemented by the Bell states. These schemes need a trusted
information center like that in the classic cryptography. The optimal
efficiency of the proposed protocols are higher than that in the previous
schemes.

</DOC>
<DOC>
<DOCNO> 120134 </DOCNO>
Supernovae evidence for an accelerating expansion of the universe


  Recent experimental results find strong indications that the universe is
flat, while other experimental results from supernovae Ia observations have
been interpreted to show that, not only that there is an accelerating expansion
of the universe, but also that the universe is strongly curved. By means of a
recently proposed metric, I am able to show that the experimental results which
had previously been analyzed to give a strong curvature are quite consistent
with a flat universe, thus resolving the apparent mismatch. The conclusion of
these latter authors which indicated an accelerating expansion of the universe
remains unchanged.

</DOC>
<DOC>
<DOCNO> 119301 </DOCNO>
Synthetic post-Asymptotic Giant Branch evolution: basic models and


  We explore the realm of post-Asymptotic Giant Branch (post-AGB) stars from a
theoretical viewpoint, by constructing synthetic population of transition
objects, proto-Planetary Nebulae, Planetary Nebulae Nuclei, and post-Planetary
Nebulae objects. We use the Montecarlo procedure to filter out the populations
accordingly to a given set of assumptions. We explore the parameter space by
studying the effects of the Initial Mass Function (IMF), the Initial Mass-Final
Mass Relation (IMFMR), the transition time (t_tr), the envelope mass at the end
of the envelope ejection (Me_r), the planetary nebula lifetime t_PN, the
hydrogen- and helium-burning phases of the central stars. The results are
discussed on the basis of the HR diagram distributions, on the Mv-t plane, and
with mass histograms. We found that: (1) the dependence of the synthetic
populations on the assumed IMF and IMFMR is generally mild; (2) the Me_r
indetermination produces very high indeterminations on the t_tr and thus on the
resulting post-AGB populations; (3) the synthetic models give a test check for
the ratio of He- to H-burning PNNi. In this paper, disk post-AGB populations
are considered. Future applications will include Magellanic Clouds PNe, and
populations of bulges and elliptical galaxies.

</DOC>
<DOC>
<DOCNO> 39775 </DOCNO>
Search for spatial anisotropy in beta-decays


  Theoretically a possibility of covariance violation in weak decays is not
ruled out from the first principles, while there are some models predicting
non-covariance revealed in weak interactions. The experimental evidence for
isotropy violation in $\beta$-decays was recently reported. We present a study
of the dependence of electron flow rate and $\beta$-electron energy in the
decay of $Sr^{90}$ with respect to the direction of electron emission. An upper
limit of $1.4 \cdot 10^{-5}$ on directional dependence of $\beta$-electron
energy was obtained.

</DOC>
<DOC>
<DOCNO> 178407 </DOCNO>
$\rho$ - nucleus bound states in Walecka model


  Possible formation of $\rho$ nucleus bound state is studied in the framework
of Walecka model. The bound states are found in different nuclei ranging from
$^3He$ to $^{208}Pb$. These bound states may have a direct bearing on the
recent experiments on the photoproduction of $\rho$ meson in the nuclear
medium.

</DOC>
<DOC>
<DOCNO> 101376 </DOCNO>
Quasi-Commuting Families of Quantum Minors


  We produce neccessary and sufficient conditions for pairs of quantum minors
in the quantized coordinate algebra $\Bbb{C}_q[Mat_{k \times m}]$ to
quasi-commute. In addition we study the combinatorics of maximal (by inclusion)
families of pairwise quasi-commuting quantum minors.

</DOC>
<DOC>
<DOCNO> 9470 </DOCNO>
Site-selective nuclear magnetic relaxation time in a superconducting


  The temperature and field dependences of the site-selective nuclear spin
relaxation time T_1 around vortices are studied comparatively both for s-wave
and d-wave superconductors, based on the microscopic Bogoliubov-de Gennes
theory. Reflecting low energy electronic excitations associated with the vortex
core, the site selective temperature dependences deviate from those of the
zero-field case, and T_1 becomes faster with approaching the vortex core. In
the core region, T_1^{-1} has a new peak below the superconducting transition
temperature T_c. The field dependence of the overall T_1(T) behaviors for
s-wave and d-wave superconductors is investigated and analyzed in terms of the
local density of states. The NMR study by the resonance field dependence may be
a new method to probe the spatial resolved vortex core structure in various
conventional and unconventional superconductors.

</DOC>
<DOC>
<DOCNO> 8787 </DOCNO>
Magnetic field - temperature phase diagram of the organic conductor


  We present systematic magnetic torque studies of the ``magnetic field -
temperature'' phase diagram of the layered organic conductor
alpha-(BEDT-TTF)2KHg(SCN)4 at fields nearly perpendicular and nearly parallel
to the highly conducting plane. The shape of the phase diagram is compared to
that predicted for a charge-density-wave system in a broad field range.

</DOC>
<DOC>
<DOCNO> 102272 </DOCNO>
Differential forms and smoothness of quotients by reductive groups


  In this paper we give smoothness criterions for a good quotient Y of a smooth
variety X by a reductive group G. Our results partially answer a question
raised by J. Fogarty in the case where G is a finite group. They also give a
converse to a theorem of M. Brion, telling that invariant horizontal
differential forms on X and differential forms on Y are isomorphic under the
assumption that Y is smooth. The proof of our criterion rely on a new
description of the dualizing sheaf of Y established in this article.

</DOC>
<DOC>
<DOCNO> 84507 </DOCNO>
Black Hole Emergence in Supernovae


  If a black hole formed in a core-collapse supernova is accreting material
from the base of the envelope, the accretion luminosity could be observable in
the supernova light curve. Here we continue the study of matter fall back onto
a black hole in the wake of a supernova and examine realistic supernovae models
which allow for an early emergence of the accretion luminosity. Such cases may
provide a direct observational identification of the black hole formed in the
aftermath of the explosion. Our approach combines analytic estimates and fully
relativistic, radiation-hydrodynamic numerical computations. We employ a
numerical hydrodynamical scaling technique to accommodate the diverse range of
dynamical time scales in a single simulation. We find that while in typical
Type II supernovae heating by radioactive decays dominates the late-time light
curve, low-energy explosions of more massive stars should provide an important
exception where the accretion luminosity will emerge while it is still
relatively large. Our main focus is on the only current candidate for such an
observation, the very unusual SN1997D. Due to the low energy of the explosion
and the very small ($2\times10^{-3} M_\sun$) inferred mass of Co56 in the
ejected envelope, we find that accretion should become the dominant source of
its luminosity during the year 2000. The total luminosity at emergence is
expected to lie in the range $0.5-3\times10^{36} $ ergs/s, potentially
detectable with HST. We also discuss the more favorable case of explosions
which eject negligible amounts of radioactive isotopes and find that the black
hole is likely to emerge a few tens of days after the explosion, with a
luminosity of $\sim 10^{37} $\ergss.

</DOC>
<DOC>
<DOCNO> 151936 </DOCNO>
Holography and the origin of anomalies


  The holographic principle is represented as the well-known de Alfaro, Fubini
and Furlan correspondence between the generating functional for the Green
functions of the Euclidean quantum field theory in $D$ dimensions and the Gibbs
average for the classical statistical mechanics in $D+1$ dimensions. This
correspondence is used to explain the origin of quantum anomalies and the
irreversibility in the classical theory. The holographic mapping of a classical
string field theory onto a local quantum field theory is outlined.

</DOC>
<DOC>
<DOCNO> 123194 </DOCNO>
Winds from massive stars: implications for the afterglows of gamma-ray


  Recent observations suggest that long-duration gamma-ray bursts (GRBs) and
their afterglows are produced by highly relativistic jets emitted in
core-collapse explosions. The pre-explosive ambient medium provides a natural
test for the most likely progenitors of GRBs. Those stars that shed their
envelopes most readily have short jet crossing times and are more likely to
produce a GRB. We construct a simple computational scheme to explore the
expected contribution of the presupernova ejecta of single Wolf-Rayet (WR)
stars to the circumstellar environment. Using detailed stellar tracks for the
evolution of massive stars, we discuss the effects that the initial main
sequence mass, metallicity, rotation and membership in a binary system have on
the ambient medium. We extend the theory of GRB afterglows in winds to consider
the effect of the relativistic fireball propagating through the WR ejecta. We
make specific predictions for the interaction of the relativistic blast wave
with the density bumps that arise when the progenitor star rapidly loses a
large fraction of its initial mass or when the ejected wind interacts with the
external medium and decelerates. A re-brightening of the afterglow with a
spectrum redder than the typical synchrotron spectrum (as seen in GRB 970508,
GRB 980326 and GRB 000911) is predicted. We also calculate the luminosity of
the reflected echo that arises when circumstellar material Compton-scatters the
prompt radiation and examine the spectral signatures expected from the
interaction of the GRB afterglow with the ejected medium.

</DOC>
<DOC>
<DOCNO> 100763 </DOCNO>
Standard modules of quantum affine algebras


  We give a proof of the cyclicity conjecture of Akasaka-Kashiwara, for simply
laced types, via quiver varieties. We get also an algebraic characterization of
the standard modules.

</DOC>
<DOC>
<DOCNO> 10684 </DOCNO>
Wigner-Dyson Statistics from the Keldysh Sigma-Model


  The level statistics of disordered metallic grains with broken time reversal
invariance is obtained from a saddle point analysis of the Keldysh nonlinear
sigma-model.

</DOC>
<DOC>
<DOCNO> 116575 </DOCNO>
Coherent transients in optical lattices


  We use a method based on optical coherent transients to study the vibrational
coherence lifetimes of atoms trapped in the potential wells of a near-resonant
optical lattice in the oscillating regime. The dependence of the positions and
widths of the vibrational Raman resonances of the coherent transient spectra on
the intensity, detuning, and geometry of the lattice beams is investigated and
the results are compared with theoretical predictions. It is shown that the
principal source of broadening of the vibrational Raman resonances is the
anharmonicity of the light-shift potential wells. We also perform time-resolved
measurements of the vibrational excitation of atoms equilibrating in an optical
lattice.

</DOC>
<DOC>
<DOCNO> 10343 </DOCNO>
Pareto's Law for Income of Individuals and Debt of Bankrupt Companies


  We analyze the distribution of income and income tax of individuals in Japan
for the fiscal year 1998. From the rank-size plots we find that the accumulated
probability distribution of both data obey a power law with a Pareto exponent
very close to -2. We also present an analysis of the distribution of the debts
owed by bankrupt companies from 1997 to March, 2000, which is consistent with a
power law behavior with a Pareto exponent equal to -1. This power law is the
same as that of the income distribution of companies. Possible implications of
these findings for model building are discussed.

</DOC>
<DOC>
<DOCNO> 123038 </DOCNO>
VLBI, MERLIN and HST observations of the giant radio galaxy 3C236


  We present VLBI and MERLIN data at 1.66 and 4.99 GHz on the central component
coincident with the nucleus of the giant radio galaxy, 3C236. The nuclear radio
structure is composed of two complexes of emission which are resolved on scales
from 1 milli-arcsec (mas) to 1 arcsec. Oscillations with an amplitude of about
5 degrees can be seen in the compact radio structure. Spectral index
distributions are plotted at angular resolutions of 10 and 25 mas and allow us
to identify the core component in the south-east emission complex.
Re-examination of the HST WFPC-2 image of 3C236 by de Koff et al. (2000), shows
that the normal to the dust disk in the nucleus is ~30 degrees from the plane
of the sky and within 12 degrees of parallel to the overall orientation of the
radio source. We suggest that the radio axis is also at an angle of ~30 degrees
to the plane of the sky and that the north-west jet is on the approaching side.
This orientation implies an overall size of 4.5 Mpc (H_o = 75 km/s/Mpc, q_o =
0.5) for 3C236. The coincidence of a dust feature and the south-east compact
jet, within the astrometric errors, leads us to suggest that the dust may be in
the form of a cloud encountered by the jet in the first ~400 pc of its journey
out from the nucleus. One-sided emission at 5 GHz on 1 mas scales would suggest
that the jets are ejected initially at <= 35 degrees to the line of sight, but
this is difficult to reconcile with the obvious orientation stability of the
jet system as a whole. Free-free absorption of the counter-jet may be an
alternative explanation for the one-sideness.

</DOC>
<DOC>
<DOCNO> 84615 </DOCNO>
Logarithmic Corrections to Black Hole Entropy from the Cardy Formula


  Many recent attempts to calculate black hole entropy from first principles
rely on conformal field theory techniques. By examining the logarithmic
corrections to the Cardy formula, I compute the first-order quantum correction
to the Bekenstein-Hawking entropy in several models, including those based on
asymptotic symmetries, horizon symmetries, and certain string theories. Despite
very different physical assumptions, these models all give a correction
proportional to the logarithm of the horizon size, and agree qualitatively with
recent results from ``quantum geometry'' in 3+1 dimensions. There are some
indications that even the coefficient of the correction may be universal, up to
differences that depend on the treatment of angular momentum and conserved
charges.

</DOC>
<DOC>
<DOCNO> 120094 </DOCNO>
The morphology of the emission line region of Compact Steep Spectrum


  We present the results of HST narrow band imaging of eleven Compact Steep
Spectrum (CSS) radio sources. Five of them (3C 48, 3C 147, 3C303.1, 3C 277.1
and 4C 12.50) were part of a dedicated ``pointed'' program of deep line imaging
([OIII]). For six additional sources (3C 49, 3C 93.1, 3C 138, 3C 268.3, 3C305.1
and 3C343.1) ``snapshot'' images ([OIII] or [OII]) were taken from the HST
archive. In all but one of the targets (3C 49) line emission has been detected
and only in one case (3C 138) is unresolved. In four out five of the sources
with deep observations, the line emission extends well beyond the size of the
radio source but along the radio axis. Structures of similar surface brightness
would have not been seen in the snapshot images. These emission line structures
extend to scales of 10 to 30 kpc and cover a projected angle, when seen from
the nucleus, of 30 to 110 degrees, indicating that the nuclear illumination is
anisotropic. Photon counting arguments also support this interpretation. In six
objects the radio emission extends over more than 1 arcsec. In these cases the
line emission has an elongated structure, linking the nucleus to the
radio-lobes, possibly tracing the path of the invisible radio jets.
Nevertheless the emission line morphologies do not show the bow shocks at the
extremities of the radio lobes expected if they are sources whose expansion is
frustrated by a dense external medium. Our data favour the alternative model in
which CSSs are the young phase of the large size radio sources. When
``pointed'' pure continuum images are available, there appears to be no
alignment between radio and continuum emission which contradicts previous
suggestions based on broad-band HST imaging.

</DOC>
<DOC>
<DOCNO> 121154 </DOCNO>
Near-infrared imaging of the host galaxies of intermediate redshift


  We present the results of near-infrared H-band (1.65 microns) imaging of 19
steep spectrum radio quasars (SSRQ) in the redshift range 0.5 < z < 1.0. This
sample of SSRQs is matched with our previously studied complete sample of 20
flat spectrum radio quasars (FSRQ) with respect to redshift and optical and
radio luminosity. We are able to clearly detect the host galaxy in 10 (53 %)
SSRQs and marginally in 6 (32 %) others, while the host remains unresolved in 3
(16 %) SSRQs. The galaxies hosting the SSRQs are large (average bulge
scale-length R(e) = 9.0+-1.7 kpc) and luminous (average M(H) = -27.2+-1.1).
They are, therefore, about 2 mag more luminous than the typical galaxy
luminosity L* (M*(H) = -25.0+-0.2), and about 1 mag more luminous than the
brightest cluster galaxies (M(H) = -26.3+-0.3). The SSRQ hosts appear to have
similar luminosity to those of the FSRQ hosts (M(H) = -27), and they fall
between the luminosities of lower redshift (M(H) = -26) and higher redshift
(M(H) = -29) radio-loud quasars. The average nucleus-to-galaxy luminosity ratio
of SSRQs (LN/LG = 3.8+-3.2) is much smaller than that found for the FSRQs
(LN/LG = 21+-11), in good agreement with the current unified models. We confirm
for the most luminous SSRQs the trend noted for the FSRQs between the host and
nuclear luminosity. This trend supports the suggestion based on studies of
lower redshift AGN, that there is a minimum host galaxy luminosity which
increases linearly with the quasar luminosity. Finally, FSRQs seem to reside in
richer environments than SSRQs, as evidenced by a larger number of close
companion galaxies.

</DOC>
<DOC>
<DOCNO> 8148 </DOCNO>
Strange nonchaotic attractor in a dynamical system under periodic


  We observe the occurrence of a strange nonchaotic attractor in a periodically
driven two-dimensional map, formerly proposed as a neuron model and a sequence
generator. We characterize this attractor through the study of the Lyapunov
exponents, fractal dimension, autocorrelation function and power spectrum. The
strange nonchaotic attractor in this model is a typical behavior, occupying a
finite range of the parameter space.

</DOC>
<DOC>
<DOCNO> 151500 </DOCNO>
Geometrical Approach to the Gauge Field Mass Problem. Possible Reasons


  In the Kaluza - Klein approach the (4+d)-dimensional Einstein--Hilbert
gravity action is considered. The extra d-dimensional manifold V_d is a Riemann
space with the d-parametric group of isometry $G_d$ which acts on V_d by the
left shifts and with arbitrary nondegenerated left-invariant metric g_{ab}. The
gauge fields A_{\mu} are introduced as the affine connection coefficients of
the fibre bundle with V_d being the fibre. The effective Lagrangian as
invariant integral over extra-dimensional manifold of the curvative scalar of
mentioned structure is obtained. It is shown that such effective Lagrangian
contains beside the square of gauge field strength tensor also quadratic form
of A_{\mu} and all other fields have only pure gauge degrees of freedom when
g_{ab}. satisfy some conditions. This conditions may be regarded as
generalization of the General Relativity Principle to the extra dimensions. The
eigenvalues of the quadratic form of A_{\mu} are calculated for the case of
gauge group SO(3). It is shown that they are not equal to zero in the case when
g_{ab} is not proportional to the unit matrix.

</DOC>
<DOC>
<DOCNO> 121315 </DOCNO>
Ultra-high energy cosmic rays: are they isotropic?


  From the analysis of AGASA data above $4 \times 10^{19}$ eV, we show that the
ultra-high energy cosmic rays flux is neither purely isotropic, nor reflects
the expected anisotropy from a pure source distribution that maps large scale
structure in the local universe. The arrival distribution seems to be the
result of a mixture of fluxes (e.g., dark matter halo plus large scale
structure) or the superposition of a direct and a diffuse radiation field
components respectively. Another viable option is an arbitrary extragalactic
flux reprocessed by a magnetized galactic wind model as recently proposed in
the literature.

</DOC>
<DOC>
<DOCNO> 39737 </DOCNO>
Emulsion Chamber with Big Radiation Length for Detecting Neutrino


  A conceptual scheme of a hybrid-emulsion spectrometer for investigating
various channels of neutrino oscillations is proposed. The design emphasizes
detection of $\tau$ leptons by detached vertices, reliable identification of
electrons, and good spectrometry for all charged particles and photons. A
distributed target is formed by layers of low-Z material,
emulsion-plastic-emulsion sheets, and air gaps in which $\tau$ decays are
detected. The tracks of charged secondaries, including electrons, are
momentum-analyzed by curvature in magnetic field using hits in successive thin
layers of emulsion. The $\tau$ leptons are efficiently detected in all major
decay channels, including \xedec. Performance of a model spectrometer, that
contains 3 tons of nuclear emulsion and 20 tons of passive material, is
estimated for different experimental environments. When irradiated by the
$\nu_\mu$ beam of a proton accelerator over a medium baseline of $<L/E_\nu >
\sim 1$ km/GeV, the spectrometer will efficiently detect either the \omutau and
\omue transitions in the mass-difference region of $\Delta m^2 \sim 1$ eV$^2$,
as suggested by the results of LSND. When exposed to the neutrino beam of a
muon storage ring over a long baseline of $<L/E_\nu > \sim$ 10-20 km/GeV, the
model detector will efficiently probe the entire pattern of neutrino
oscillations in the region $\Delta m^2 \sim 10^{-2}-10^{-3}$ eV$^2$, as
suggested by the data on atmospheric neutrinos.

</DOC>
<DOC>
<DOCNO> 85253 </DOCNO>
Self-adjoint wave equations for dynamical perturbations of


  It is shown that the dynamical evolution of linear perturbations on a static
space-time is governed by a constrained wave equation for the extrinsic
curvature tensor. The spatial part of the wave operator is manifestly elliptic
and self-adjoint. In contrast to metric formulations, the curvature-based
approach to gravitational perturbation theory generalizes in a natural way to
self-gravitating matter fields. It is also demonstrated how to obtain symmetric
pulsation equations for self-gravitating non-Abelian gauge fields, Higgs fields
and perfect fluids. For vacuum fluctuations on a vacuum space-time, the
Regge-Wheeler and Zerilli equations are rederived.

</DOC>
<DOC>
<DOCNO> 11676 </DOCNO>
Metal-insulator transitions in cyclotron resonance of periodic


  A recently found metal-insulator transition in a model for cyclotron
resonance in a two-dimensional periodic potential is investigated by means of
spectral properties of the time evolution operator. The previously found
dynamical signatures of the transition are explained in terms of avoided band
crossings due to the change of the external electric field. The occurrence of a
cross-like transport is predicted and numerically confirmed.

</DOC>
<DOC>
<DOCNO> 120832 </DOCNO>
Evidence for Polarized Synchrotron Components in Radio-Optical Aligned


  A tendency for the axes of double-lobed radio quasars to be aligned with the
electric vectors of optical polarization in the active galactic nuclei is
well-known. However, the origin of the polarization and reason behind its
correlation with radio morphology is not yet established. From accurate
spectropolarimetry of 7 quasars which show this alignment effect, we find that
the polarization is universally confined to the continuum, and not shared by
the line emission or 3000A bump. Over the observed region 4000-8000A, the
spectral indices of polarized flux, P x Flambda, are consistent with uniform
polarization applied to the light of the big blue bump or with synchrotron
emission. However, electron scattering from an optically-thick, geometrically-
thin, accretion disk is well-known to give rise to a polarization position
angle that is perpendicular to the disk axis. Optical synchrotron emission akin
to that shown to exist in the miniblazar 3C273 is a more attractive
explanation, and supporting evidence can be found for some of the targets in
the form of polarimetric variability over intervals of years. Properties of the
most strongly-polarized radio-optical aligned quasars can be explained by
misdirected blazar core components that have net polarizations of P~10% and
provide ~10% of the total optical light.

</DOC>
<DOC>
<DOCNO> 12321 </DOCNO>
Reversible boolean networks II: Phase transition, oscillation, and local


  We continue our consideration of a class of models describing the reversible
dynamics of $N$ Boolean variables, each with $K$ inputs. We investigate in
detail the behavior of the Hamming distance as well as of the distribution of
orbit lengths as $N$ and $K$ are varied. We present numerical evidence for a
phase transition in the behavior of the Hamming distance at a critical value
$K_c\approx 1.65$ and also an analytic theory that yields the exact bounds on
$1.5 \le K_c \le 2.$
  We also discuss the large oscillations that we observe in the Hamming
distance for $K<K_c$ as a function of time as well as in the distribution of
cycle lengths as a function of cycle length for moderate $K$ both greater than
and less than $K_c$. We propose that local structures, or subsets of spins
whose dynamics are not fully coupled to the other spins in the system, play a
crucial role in generating these oscillations. The simplest of these structures
are linear chains, called linkages, and rings, called circuits. We discuss the
properties of the linkages in some detail, and sketch the properties of
circuits. We argue that the observed oscillation phenomena can be largely
understood in terms of these local structures.

</DOC>
<DOC>
<DOCNO> 67826 </DOCNO>
Z' indication from new APV data in Cesium and searches at linear


  New data on parity violation in atomic cesium can be explained by a new
neutral vector boson almost unmixed with Z, with a mass in the TeV range and
sizeable couplings to the fermions. The properties of such additional Z' can be
investigated at future linear colliders.

</DOC>
<DOC>
<DOCNO> 83493 </DOCNO>
Value Withdrawal Explanation in CSP


  This work is devoted to constraint solving motivated by the debugging of
constraint logic programs a la GNU-Prolog. The paper focuses only on the
constraints. In this framework, constraint solving amounts to domain reduction.
A computation is formalized by a chaotic iteration. The computed result is
described as a closure. This model is well suited to the design of debugging
notions and tools, for example failure explanations or error diagnosis. In this
paper we detail an application of the model to an explanation of a value
withdrawal in a domain. Some other works have already shown the interest of
such a notion of explanation not only for failure analysis.

</DOC>
<DOC>
<DOCNO> 13785 </DOCNO>
Localization Characteristics of Relativistic vs Nonrelativistic Fermions


  Relativistic fermions on a lattice are shown to correspond to the
$fluctuations$ in the localized nonrelativistic fermions. Therefore, in
contrast to nonrelativistic case, the relativistic fermions are critical with
universal exponents described by the strong coupling limit of the
nonrelativistic problem. The fluctuations also describe $anisotropic$ spin
chain at the onset to {\it long range magnetic order} whose universality class
is the Ising model. This generalizes the universality in spin models to include
multifractal exponents. Finally, analogous to the nonrelativistic case, the
relativistic fermions may exhibit ballistic character due to correlations.

</DOC>
<DOC>
<DOCNO> 83135 </DOCNO>
Coherence, Belief Expansion and Bayesian Networks


  We construct a probabilistic coherence measure for information sets which
determines a partial coherence ordering. This measure is applied in
constructing a criterion for expanding our beliefs in the face of new
information. A number of idealizations are being made which can be relaxed by
an appeal to Bayesian Networks.

</DOC>
<DOC>
<DOCNO> 80613 </DOCNO>
Quenched QCD near the chiral limit


  A numerical study of quenched QCD for light quarks is presented using O(a)
improved fermions. Particular attention is paid to the possible existence and
determination of quenched chiral logarithms. A `safe' region to use for chiral
extrapolations appears to be at and above the strange quark mass.

</DOC>
<DOC>
<DOCNO> 10843 </DOCNO>
Extension to order $\beta^{23}$ of the high-temperature expansions for


  Using a renormalized linked-cluster-expansion method, we have extended to
order $\beta^{23}$ the high-temperature series for the susceptibility $\chi$
and the second-moment correlation length $\xi$ of the spin-1/2 Ising models on
the sc and the bcc lattices. A study of these expansions yields updated direct
estimates of universal parameters, such as exponents and amplitude ratios,
which characterize the critical behavior of $\chi$ and $\xi$. Our best
estimates for the inverse critical temperatures are
 $\beta^{sc}_c=0.221654(1)$ and $\beta^{bcc}_c=0.1573725(6)$. For the
susceptibility exponent we get $\gamma=1.2375(6)$ and for the correlation
length exponent we get $\nu=0.6302(4)$.
 The ratio of the critical amplitudes of $\chi$ above and below the critical
temperature is estimated to be $C_+/C_-=4.762(8)$. The analogous ratio for
$\xi$ is estimated to be $f_+/f_-=1.963(8)$. For the correction-to-scaling
amplitude ratio we obtain $a^+_{\xi}/a^+_{\chi}=0.87(6)$.

</DOC>
<DOC>
<DOCNO> 69361 </DOCNO>
The $b\to s\gamma$ decay in SUSY models with non-universal A-terms


  We analyse the predictions for the inclusive branching ratio for $b\to
s\gamma$ decay in a class of string-inspired SUSY models with non-universal
soft-breaking A-terms. These models are particularly interesting since the
non-universality of the A-terms plays an important role in providing new
significant contributions to CP violation effects in kaon physics while
respecting the severe bounds on electric dipole moments. We show that $b\to
s\gamma$ do not severely constrain the non-universality of these models. In
particular, at low $\tan\beta$ $(\tan\beta\simeq 2)$, our predictions are close
to the universal case. For large $\tan\beta$ ($\tan\beta \gsim 15$),the effect
of non-universality is enhanced and stronger constraints hold. We find that the
parameter regions which are important for generating sizeable contribution to
$\epsilon'/\epsilon$, of order $2 \times 10^{-3}$, are not excluded.

</DOC>
<DOC>
<DOCNO> 11414 </DOCNO>
Fine-grid Simulations of Thermally Activated Switching in Nanoscale


  Numerical integration of the Landau-Lifshitz-Gilbert equation with thermal
fluctuations is used to study the dynamic response of single-domain nanomagnets
to rapid changes in the applied magnetic field. The simulation can resolve
magnetization patterns within nanomagnets and uses the Fast Multipole method to
calculate dipole-dipole interactions efficiently. The thermal fluctuations play
an essential part in the reversal process whenever the applied field is less
than the zero-temperature coercive field. In this situation pillar-shaped
nanomagnets are found to reverse through a local curling mode that involves the
formation and propagation of a domain wall. Tapering the ends of the pillars to
reduce pole-avoidance effects changes the energies involved but not the
fundamental process. The statistical distribution of switching times is well
described by the independent nucleation and subsequent growth of regions of
reversed magnetization at both ends of the pillar.

</DOC>
<DOC>
<DOCNO> 169773 </DOCNO>
The Haroche-Ramsey experiment as a generalized measurement


  A number of atomic beam experiments, related to the Ramsey experiment and a
recent experiment by Brune et al., are studied with respect to the question of
complementarity. Three different procedures for obtaining information on the
state of the incoming atom are compared. Positive operator-valued measures are
explicitly calculated. It is demonstrated that, in principle, it is possible to
choose the experimental arrangement so as to admit an interpretation as a joint
non-ideal measurement yielding interference and ``which-way'' information.
Comparison of the different measurements gives insight into the question of
which information is provided by a (generalized) quantum mechanical
measurement. For this purpose the subspaces of Hilbert-Schmidt space, spanned
by the operators of the POVM, are determined for different measurement
arrangements and different values of the parameters.

</DOC>
<DOC>
<DOCNO> 123043 </DOCNO>
The Galaxy Environment of Quasars in the Clowes-Campusano Large Quasar


  The Clowes-Campusano Large Quasar Group (LQG) is the largest known structure
at high redshifts, with at least 18 quasars at z~1.3 forming a structure ~200
Mpc across. We are conducting an ultra-deep optical and deep NIR study to
examine the galaxy environment of quasars in this LQG to determine if, and how,
LQGs trace large-scale structure at early epochs. We report significant
associated clustering in the field of a z=1.226 quasar from this LQG in the
form of a factor ~11 overdensity of I-K>3.75 galaxies, and red sequences of
15-18 galaxies at I-K~4.3,V-K~6.9, indicative of a population of massive
ellipticals at the quasar redshift. The quasar is located between two groups of
these galaxies, with further clustering extending over 2-3 Mpc. Within 30
arcsec of the quasar we find a concentration of blue (V-I<1) galaxies in a band
that bisects the two groups of red sequence galaxies. This band is presumed to
correspond to a region of enhanced star-formation. We suggest that the merging
of the two groups of red sequence galaxies has triggered both the quasar and
the band of star-formation. Quasars at z~1.3 are located in a variety of
environments, but those with associated clustering are found on the cluster
peripheries.

</DOC>
<DOC>
<DOCNO> 118171 </DOCNO>
Current cosmological constraints from a 10 parameter CMB analysis


  We compute the constraints on a ``standard'' 10 parameter cold dark matter
(CDM) model from the most recent CMB and data and other observations, exploring
30 million discrete models and two continuous parameters. Our parameters are
the densities of CDM, baryons, neutrinos, vacuum energy and curvature, the
reionization optical depth, and the normalization and tilt for both scalar and
tensor fluctuations.
   Our strongest constraints are on spatial curvature, -0.24 < Omega_k < 0.38,
and CDM density, h^2 Omega_cdm <0.3, both at 95%. Including SN 1a constraints
gives a positive cosmological constant at high significance.
   We explore the robustness of our results to various assumptions. We find
that three different data subsets give qualitatively consistent constraints.
Some of the technical issues that have the largest impact are the inclusion of
calibration errors, closed models, gravity waves, reionization, nucleosynthesis
constraints and 10-dimensional likelihood interpolation.

</DOC>
<DOC>
<DOCNO> 39964 </DOCNO>
Statistical properties of the estimator using covariance matrix


  The statistical properties of estimator using covariance matrix for the
account of point-to-point correlations due to systematic errors are analyzed.
It is shown that the covariance matrix estimator (CME) is consistent for the
realistic cases (when systematic errors on the fitted parameters are not
extremely large comparing with the statistical ones) and its dispersion is
always smaller, than the dispersion of the simplified $\chi^2$ estimator
applied to the correlated data. The CME bias is negligible for the realistic
cases if the covariance matrix is calculated during the fit iteratively using
the parameter estimator itself. Analytical formula for the covariance matrix
inversion allows to perform fast and precise calculations even for very large
data sets. All this allows for efficient use of the CME in the global fits.

</DOC>
<DOC>
<DOCNO> 100086 </DOCNO>
There are enough Azumaya algebras on surfaces


  Using Maruyama's theory of elementary transformations, I show that the Brauer
group surjects onto the cohomological Brauer group for separated geometrically
normal algebraic surfaces. As an application, I infer the existence of nonfree
vector bundles on proper normal algebraic surfaces.

</DOC>
<DOC>
<DOCNO> 119003 </DOCNO>
On 7Li Enrichment by Low Mass Metal Poor Red Giant Branch Stars


  First-ascent red giants with strong and very strong Li lines have just been
discovered in globular clusters. Using the stellar internal prompt 7Li
enrichment - mass loss scenario, we explore the possibility of 7Li enrichment
in the interstellar matter of the globular cluster M3 produced by these Li-rich
giants. We found that enrichment as large as 70% or more compared to the
initial 7Li content of M3 can be obtained during the entire life of this
cluster. However, due to the several crossings of M3 into the Galactic plane,
the new 7Li will be very probably removed by ram pressure into the disk.
Globular clusters appear then as possible new sources of 7Li in the galactic
disk. It is also suggested that the known Na/Al variations in stars of globular
clusters could be somehow related to the 7Li variations and that the cool
bottom mixing mechanism acting in the case of 7Li could also play a role in the
case of Na and Al surface enrichments.

</DOC>
<DOC>
<DOCNO> 119444 </DOCNO>
A theoretical light-curve model for the 1985 outburst of RS Ophiuchi


  A theoretical light-curve model of the 1985 outburst of RS Ophiuchi is
presented based on a thermonuclear runaway (TNR) model. The system consists of
a very massive white dwarf (WD) with an accretion disk (ACDK) and a red giant
(RG). The early phase of the V light curve is well reproduced only by the
bloated WD photosphere of the TNR model on a 1.35 +/- 0.01 M_sun WD while the
later phase is dominated both by the irradiated ACDK and by the irradiated RG
underfilling the inner critical Roche lobe. The UV light curve is also well
reproduced by the same model with the distance of 0.6 kpc to RS Oph. The
envelope mass at the optical peak is estimated to be 2 x 10^{-6} M_sun,
indicating a rather high mass accretion rate of 1.2 x 10^{-7} M_sun yr^{-1}
between the 1967 and the 1985 outbursts. About 90% of the envelope mass is
blown off in the outburst wind while the residual 10% (2 x 10^{-7} M_sun) has
been left and added to the helium layer of the WD. The net increasing rate of
the WD mass is 1.2 x 10^{-8} M_sun yr^{-1}. Thus, RS Oph is certainly a strong
candidate for a Type Ia supernova progenitor.

</DOC>
<DOC>
<DOCNO> 70164 </DOCNO>
Quark Mass Matrices with Four and Five Texture Zeroes, and the CKM


  Using the triangular matrix techniques of Kuo et al and Chiu et al for the
four and five texture zero cases, with vanishing (11) elements for U and D
matrices, it is shown, from the general eigenvalue equations and hierarchy
conditions, that the quark mass matrices, and the CKM matrix can be expressed
(except for the phases) entirely in terms of quark masses. The matrix
structures are then quite simple and transparent. We confirm their results for
the five texture zero case but find, upon closer examination of all the CKM
elements which our results provide, that six of their nine patterns for the
four texture zero case are not compatible with experiments. In total, only one
five-texture zero and three four-texture zero patterns are allowed.

</DOC>
<DOC>
<DOCNO> 10492 </DOCNO>
HARES: an efficient method for first-principles electronic structure


  We discuss our new implementation of the Real-space Electronic Structure
method for studying the atomic and electronic structure of infinite periodic as
well as finite systems, based on density functional theory. This improved
version which we call HARES (for High-performance-fortran Adaptive grid
Real-space Electronic Structure) aims at making the method widely applicable
and efficient, using high performance Fortran on parallel architectures. The
scaling of various parts of a HARES calculation is analyzed and compared to
that of plane-wave based methods. The new developments that lead to enhanced
performance, and their parallel implementation, are presented in detail. We
illustrate the application of HARES to the study of elemental crystalline
solids, molecules and complex crystalline materials, such as blue bronze and
zeolites.

</DOC>
<DOC>
<DOCNO> 85424 </DOCNO>
Dynamics of a string coupled to gravitational waves II - Perturbations


  The perturbative modes propagating along an infinite string are investigated
within the framework of the gauge invariant perturbation formalism on a
spacetime containing a self-gravitating straight string with a finite
thickness. These modes are not included in our previous analysis. We
reconstruct the perturbation formalism to discuss these modes and solve the
linearized Einstein equation within the first order with respect to the string
oscillation amplitude. In the thin string case, we show that the oscillations
of an infinite string must involve the propagation of cosmic string traveling
wave.

</DOC>
<DOC>
<DOCNO> 100091 </DOCNO>
Beyond pair correlation


  The authors study the distribution of psi(x+h)-psi(x)-h and compare it with
numerical data.

</DOC>
<DOC>
<DOCNO> 179005 </DOCNO>
Structure and properties of neutron stars in the Relativistic Mean -


  Properties of rotating neutron stars with the use of relativistic mean-field
theory are considered. The performed analysis of neutron star matter is based
on the nonlinear Lgrangian density. The presence of nonlinear interaction of
vector mesons modifies the density dependence of the rho field and influences
bulk parameters of neutron stars. The observed quasi-periodic X-ray
oscillations of low mass X-ray binaries can be used in order to constrain the
equation of state of neutron star matter. Having assumed that the maximum
frequency of the quasi periodic oscillations originates at the circular orbit
it is possible to estimate masses and radii of neutron stars.

</DOC>
<DOC>
<DOCNO> 119439 </DOCNO>
Compton Scattering in Ultra-Strong Magnetic Fields: Numerical and


  This paper explores the effects of strong magnetic fields on the Compton
scattering of relativistic electrons. Recent studies of upscattering and energy
loss by relativistic electrons that have used the non-relativistic, magnetic
Thomson cross section for resonant scattering or the Klein-Nishina cross
section for non-resonant scattering do not account for the relativistic quantum
effects of strong fields ($ > 4 \times 10^{12}$ G). We have derived a
simplified expression for the exact QED scattering cross section for the
broadly-applicable case where relativistic electrons move along the magnetic
field. To facilitate applications to astrophysical models, we have also
developed compact approximate expressions for both the differential and total
polarization-dependent cross sections, with the latter representing well the
exact total QED cross section even at the high fields believed to be present in
environments near the stellar surfaces of Soft Gamma-Ray Repeaters and
Anomalous X-Ray Pulsars. We find that strong magnetic fields significantly
lower the Compton scattering cross section below and at the resonance, when the
incident photon energy exceeds $m_ec^2$ in the electron rest frame. The cross
section is strongly dependent on the polarization of the final scattered
photon. Below the cyclotron fundamental, mostly photons of perpendicular
polarization are produced in scatterings, a situation that also arises above
this resonance for sub-critical fields. However, an interesting discovery is
that for super-critical fields, a preponderance of photons of parallel
polarization results from scatterings above the cyclotron fundamental. This
characteristic is both a relativistic and magnetic effect not present in the
Thomson or Klein-Nishina limits.

</DOC>
<DOC>
<DOCNO> 118114 </DOCNO>
Overmerging in N-body simulations


  The aim of this paper is to clarify the notion and cause of overmerging in
N-body simulations, and to present analytical estimates for its timescale.
Overmerging is the disruption of subhaloes within embedding haloes due to {\it
numerical} problems connected with the discreteness of N-body dynamics. It is
shown that the process responsible for overmerging is particle-subhalo two-body
heating. Various solutions to the overmerging problem are discussed

</DOC>
<DOC>
<DOCNO> 83080 </DOCNO>
Fully Sequential and Distributed Dynamic Algorithms for Minimum Spanning


  In this paper, we present a fully-dynamic distributed algorithm for
maintaining a minimum spanning tree on general graphs with positive real edge
weights. The goal of a dynamic MST algorithm is to update efficiently the
minimum spanning tree after dynamic changes like edge weight changes, rather
than having to recompute it from scatch each time. The first part of the paper
surveys various algorithms available today both in sequential and distributed
environments to solve static MST problem. We also present some of the efficient
sequential algorithms for computing dynamic MST like the Frederickson's
algorithm and Eppstein's sparsification technique. Lastly we present our new
sequential and distributed algorithms for dynamic MST problem. To our
knowledge, this is the first of the distributed algorithms for computing
dynamic MSTs.

</DOC>
<DOC>
<DOCNO> 9777 </DOCNO>
Rotational spectra of weakly interacting Bose-Einstein condensates


  We study the spectrum of rotating Bose-Einstein Condensates in the limit of
weak repulsive interactions and present analytical and numerical results for
energies and wave functions. While the low-lying states are of collective
nature, the high-lying states are dominated by single-particle excitations and
can accurately approximated by simple polynomial expressions. In the limit that
the number of particles is large compared to the number of excited quanta, the
single-particle states become excellent approximations to the eigenstates, and
a rather simple ordering scheme is obtained.

</DOC>
<DOC>
<DOCNO> 71102 </DOCNO>
P-Odd Asymmetry in the Deuteron Disintegration by Circularly Polarized


  We calculate P-odd difference of the total cross-sections of the deuteron
disintegration by left and right polarized photons. The relative magnitude of
this difference in the threshold region is about 10^{-7}. Its experimental
measurement would give valuable information on the weak nucleon-nucleon
interaction at short distances.

</DOC>
<DOC>
<DOCNO> 8104 </DOCNO>
Quantum Stochastic Resonance in Electron Shelving


  Stochastic resonance shows that under some circumstances noise can enhance
the response of a system to a periodic force. While this effect has been
extensively investigated theoretically and demonstrated experimentally in
classical systems, there is complete lack of experimental evidence within the
purely quantum mechanical domain. Here we demonstrate that stochastic resonance
can be exhibited in a single ion and would be experimentally observable using
well mastered experimental techniques. We discuss the use of this scheme for
the detection of the frequency difference of two lasers to demonstrate that
stochastic resonance may have applications in precision measurements at the
quantum limit.

</DOC>
<DOC>
<DOCNO> 10256 </DOCNO>
Hartree-Fock Theory of Hole Stripe States


  We report on Hartree-Fock theory results for stripe states of two-dimensional
hole systems in quantum wells grown on GaAs (311)A substrates. We find that the
stripe orientation energy has a rich dependence on hole density, and on
in-plane field magnitude and orientation. Unlike the electron case, the
orientation energy is non-zero for zero in-plane field, and the ground state
orientation can be either parallel or perpendicular to a finite in-plane field.
We predict an orientation reversal transition in in-plane fields applied along
the $\lbrack\bar{2}33\rbrack$ direction.

</DOC>
<DOC>
<DOCNO> 67958 </DOCNO>
The modulation effect for supersymmetric dark matter detection with


  The detection of the theoretically expected dark matter is central to
particle physics cosmology. Current fashionable supersymmetric models provide a
natural dark matter candidate which is the lightest supersymmetric particle
(LSP). Such models combined with fairly well understood physics like the quark
substructure of the nucleon and the nuclear form factor and the spin response
function of the nucleus, permit the evaluation of the event rate for
LSP-nucleus elastic scattering. The thus obtained event rates are, however,
very low or even undetectable. So it is imperative to exploit the modulation
effect, i.e. the dependence of the event rate on the earth's annual motion. In
this review we study such a modulation effect in directional and undirectional
experiments. We calculate both the differential and the total rates using
symmetric as well as asymmetric velocity distributions. We find that in the
symmetric case the modulation amplitude is small, less than 0.07. There exist,
however, regions of the phase space and experimental conditions such that the
effect can become larger. The inclusion of asymmetry, with a realistic enhanced
velocity dispersion in the galactocentric direction, yields the bonus of an
enhanced modulation effect, with an amplitude which for certain parameters can
become as large as 0.46.

</DOC>
<DOC>
<DOCNO> 150493 </DOCNO>
Skyrmions from SU(3) harmonic maps and their quantization


  Static properties of SU(3) multiskyrmions with baryon number up to 6
(classical masses and momenta of inertia) are estimated. The calculations are
based on the recently suggested generalization of the SU(2) rational map
ansaetze applied to the SU(3) model. Both SU(2) embedded skyrmions and genuine
SU(3) solutions are considered, and it is shown that although, at the classical
level, the energy of embeddings is lower, the quantum corrections can alter
this conclusion. This correction to the energy of lowest state, bilinear in the
Wess-Zumino (WZ) term, is presented for the most general case as a convolution
of the inverse tensor of inertia and the components of the WZ-term.

</DOC>
<DOC>
<DOCNO> 150567 </DOCNO>
On the Spatial Structure of Monopoles


  We study the spatial structure of 1/4 BPS solitons in 4 dimensional N=4 gauge
theory. A weak binding approximation is used where the soliton is made of
several "ingredient" particles. Some spatial moduli are described which are not
accounted for in the (p,q) web picture. These moduli are counted and their
effect on the solutions is demonstrated. The potential for off BPS
configurations is estimated by a simple expression and is found to agree with
previous expressions. We discuss the fermionic zero modes of the solitons, and
find agreement with web predictions.

</DOC>
<DOC>
<DOCNO> 99379 </DOCNO>
Integrality of L2-Betti numbers


  The Atiyah conjecture predicts that the L2-Betti numbers of a finite
CW-complex with torsion-free fundamental group are integers. We show that the
Atiyah conjecture holds (with an additional technical condition) for direct and
inverse limits of directed systems of groups for which it is true. As a
corollary it holds for residually torsion-free solvable groups, e.g. for pure
braid groups or for positive 1-relator groups with torsion free abelianization.
  Putting everything together we establish a new class of groups for which the
Atiyah conjecture holds, which contains all free groups and in particular is
closed under taking subgroups, direct sums, free products, extensions with
elementary amenable quotient, and under direct and inverse limits of directed
systems.
  This is a corrected version of an older paper with the same title.
  The proof of Proposition 2.1 of the earlier version contains a gap, as was
pointed out to me by Pere Ara. This gap could not be fixed. Consequently, in
this new version everything based on this result had to be removed.

</DOC>
<DOC>
<DOCNO> 151775 </DOCNO>
Recent Developments in Discrete Torsion


  In this short note we briefly review some recent developments in
understanding discrete torsion. Specifically, we give a short overview of the
highlights of a group of recent papers which give the basic understanding of
discrete torsion. Briefly, those papers observe that discrete torsion can be
completely understood simply as the choice of action of the orbifold group on
the B field. We summarize the main points of that work.

</DOC>
<DOC>
<DOCNO> 40400 </DOCNO>
Discrete ambiguities in the determination of the CP angles


  We review briefly the problem of the discrete ambiguities in the
determination of the CKM angles, by classifying them into different categories.
We then focus on cos(2beta) and the extraction of alpha using QCD
factorization.

</DOC>
<DOC>
<DOCNO> 101214 </DOCNO>
On a proof of the 10/8-conjecture


  Let X be a smooth closed oriented non-spin 4-manifold with even intersection
form kE_8\oplus nH. In this article we show that n\geq |k| on X. Thus we
confirm the 10/8-conjecture affirmatively. As an application, we also give an
estimate of intersection forms of spin coverings of non-spin 4-manifolds with
even intersection forms.

</DOC>
<DOC>
<DOCNO> 99507 </DOCNO>
Complete classification of reflexive polyhedra in four dimensions


  Four dimensional reflexive polyhedra encode the data for smooth Calabi-Yau
threefolds that are hypersurfaces in toric varieties, and have important
applications both in perturbative and in non-perturbative string theory. We
describe how we obtained all 473,800,776 reflexive polyhedra that exist in four
dimensions and the 30,108 distinct pairs of Hodge numbers of the resulting
Calabi-Yau manifolds. As a by-product we show that all these spaces (and hence
the corresponding string vacua) are connected via a chain of singular
transitions.

</DOC>
<DOC>
<DOCNO> 85236 </DOCNO>
State sum models for quantum gravity


  This paper reviews the construction of quantum field theory on a
4-dimensional spacetime by combinatorial methods, and discusses the recent
developments in the direction of a combinatorial construction of quantum
gravity.

</DOC>
<DOC>
<DOCNO> 121442 </DOCNO>
Tidal Tails and Galaxy Evolution


  We review recent results on the tidal structures of spiral galaxies. Topics
included are general characteristics of tails; kinematics of tidal structures
and dark haloes of host galaxies; frequency of tidal distortions at z~1.

</DOC>
<DOC>
<DOCNO> 120713 </DOCNO>
The Lyman-alpha Forest Flux Distribution at z\sim 5.2 and the Evolution


  We use the redshift evolution of the lyman-alpha forest mean transmitted flux
at z>2.5 to infer the evolution of the intensity of the ionizing background,
using theoretical predictions for the density distribution of the intergalactic
gas giving rise to the lyman-alpha forest. The proper background intensity
declines gradually with redshift, decreasing by a factor \sim 3 between z=3 and
z=5.
   The gravitational structure formation theory of the lyman-alpha forest
implies that, given the observed mean transmitted flux of \bar{F}=0.1 in the
highest redshift quasar (with a mean lyman-alpha forest redshift z=5.2), only
about 3% of the lyman-alpha spectrum should have a flux higher than 50% of the
continuum, and less than 0.5% of pixels should have flux above 75% of the
continuum, assuming a uniform ionizing background intensity. We show that this
is consistent with the spectrum shown in Fan et al.

</DOC>
<DOC>
<DOCNO> 170400 </DOCNO>
Practical Quantum Cryptography: A Comprehensive Analysis (Part One)


  We perform a comprehensive analysis of practical quantum cryptography (QC)
systems implemented in actual physical environments via either free-space or
fiber-optic cable quantum channels for ground-ground, ground-satellite,
air-satellite and satellite-satellite links. (1) We obtain the complete
universal expressions for the effective secrecy capacity and rate for QC
systems taking into account the most general attacks on individual quantum
bits, including explicit closed-form expressions for the necessary and
sufficient amount of privacy amplification. Our analysis also includes the
explicit calculation in detail of the total cost in bits of continuous
authentication, thereby obtaining new results for actual ciphers of finite
length. (2) We perform for the first time a detailed, explicit analysis of all
systems losses due to propagation, errors, noise, etc. as appropriate to both
optical fiber cable- and satellite communications-based implementations of QC.
(3) We calculate for the first time all system load costs associated to
classical communication and computational constraints that are ancillary to,
but essential for carrying out, the pure QC protocol itself. (4) We introduce
an extended family of generalizations of the Bennett-Brassard (BB84) QC
protocol that equally provide unconditional secrecy but allow for the
possibility of optimizing throughput rates against specific cryptanalytic
attacks. (5) We obtain universal predictions for maximal rates that can be
achieved with practical system designs under realistic environmental
conditions. (6) We propose a specific QC system design that includes the use of
a novel method of high-speed photon detection that may be able to achieve very
high throughput rates for actual implementations in realistic environments.

</DOC>
<DOC>
<DOCNO> 9710 </DOCNO>
Copolymer at a selective interface and two dimensional wetting: a grand


  We consider two different problems involving the localization of a single
polymer chain: (i) a periodic $AB$ copolymer at a selective fluid-fluid
interface, with the upper (resp. lower) fluid attracting $A$ (resp. $B$)
monomers (ii) a homopolymer chain attracted to a hard wall (wetting). Self
avoidance is neglected in both models, which enables us to study their
localization transition in a grand canonical approach. We recover the results
obtained in previous studies via transfer matrix methods. Moreover, we
calculate in this way the loop length distribution functions in the localized
phase. Some finite size effects are also determined and tested numerically.

</DOC>
<DOC>
<DOCNO> 170055 </DOCNO>
Cooling of a single atom in an optical trap inside a resonator


  We present detailed discussions of cooling and trapping mechanisms for an
atom in an optical trap inside an optical cavity, as relevant to recent
experiments. The interference pattern of cavity QED and trapping fields in
space makes the trapping wells distinguishable from one another. This adds
considerable flexibility to creating effective trapping and cooling conditions
and to detection possibilities. Friction and diffusion coefficients are
calculated in and beyond the low excitation limit and full 3-D simulations of
the quasiclassical motion of a Cs atom are performed.

</DOC>
<DOC>
<DOCNO> 80734 </DOCNO>
Unexpected results in asymptotically free quantum field theories


  We study the behavior of asymptotically free (AF) spin and gauge models when
their continuous symmetry group is replaced by different discrete non-Abelian
subgroups. Precise numerical results with relative errors down to O(0.1%)
suggest that the models with large subgroups are in the universality class of
the underlying original models. We argue that such a scenario is consistent
with the known properties of AF theories. The small statistical errors allow a
detailed investigation of the cut-off effects also. At least up to correlation
lengths ~300 they follow effectively an O(a) rather than the expected O(a^2)
form both in the O(3) and in the dodecahedron model.

</DOC>
<DOC>
<DOCNO> 120547 </DOCNO>
Interpreting the Mg II h and k Line Profiles of Mira Variables


  We use radiative transfer calculations to reproduce the basic appearance of
Mg II lines observed from Mira variables. These lines have centroids that are
blueshifted by at least 30 km/s from the stellar rest frame. It is unlikely
that flow velocities in the stellar atmospheres are this fast, so radiative
transfer effects must be responsible for this behavior. Published hydrodynamic
models predict the existence of cool, downflowing material above the shocked
material responsible for the Mg II emission, and we demonstrate that scattering
in this layer can result in Mg II profiles as highly blueshifted as those that
are observed. However, our models also show that scattering within the shock
plays an equally strong role in shaping the Mg II profiles, and our
calculations illustrate the importance of partial redistribution and the
effects of being out of ionization equilibrium.

</DOC>
<DOC>
<DOCNO> 178918 </DOCNO>
Exploratory Calculations of the Effects of Higher Shell Admixtures on


  Using the interaction $Q \cdot Q ~+~ xV_{S.O.}$ where $V_{S.O.}$ is a
two-body spin-orbit interaction, we study the effects of varying x on the
static electric quadrupole and magnetic dipole moments of the $2^+_1$ and
$2^+_2$ states of $^{10}Be$. This is done both in the valence space $s^4p^6$
and in a larger space in which 2 $\hbar \omega$ excitations are allowed. In the
former case, for x=0, we have the Wigner Supermultiplet limit in which the
$2^+_1$ and $2^+_2$ states are degenerate and correspond to K=0 and K=2
rotational states, with equal and opposite static quadrupole moments. Turning
on the spin-orbit interaction with sufficient strength in the valence space
gives an energy splitting to the two $2^+$ states in accord with experiment.
When higher shell admixtures are allowed, we get quite a different behaviour as
a function of x than in the valence space. Of particular interest is a value of
x for which $Q(2^+_1)$ and $Q(2^+_2)$ both nearly vanish, and so does (somewhat
coincidentally) $\mu(2^+_1)$.

</DOC>
<DOC>
<DOCNO> 8508 </DOCNO>
3D van der Waals $\sigma$-model and its Topological Excitations


  It is shown that 3D vector van der Waals (conformal) nonlinear $\sigma$-model
(NSM) on a sphere $S^2$ has two types of topological excitations reminiscent
vortices and instantons of 2D NSM. The first, the hedgehogs, are described by
homotopic group $\pi_2(S^2) = \mathbb {Z}$ and have the logarithmic energies.
They are an analog of 2D vortices. The energy and interaction of these
excitations are found. The second, corresponding to 2D instantons, are
described by hpmotopic group $\pi_3(S^2) = \mathbb {Z}$ or the Hopf invariant
$H \in \mathbb {Z}$. A possibility of the topological phase transition in this
model and its applications are briefly discussed.

</DOC>
<DOC>
<DOCNO> 100891 </DOCNO>
Monodromies of Algebraic Connections on the Trivial Bundle


  In this note, we study monodromies of algebraic connections on the trivial
vector bundle. We prove that on a smooth complex affine curve, any monodromy
arises as the underlying local system of an algebraic connection on the trivial
bundle. We give a generalization of this for rank one monodromies in higher
dimension.

</DOC>
<DOC>
<DOCNO> 8490 </DOCNO>
Surface induced disorder in body-centered cubic alloys


  We present Monte Carlo simulations of surface induced disordering in a model
of a binary alloy on a bcc lattice which undergoes a first order bulk
transition from the ordered DO3 phase to the disordered A2 phase. The data are
analyzed in terms of an effective interface Hamiltonian for a system with
several order parameters in the framework of the linear renormalization
approach due to Brezin, Halperin and Leibler. We show that the model provides a
good description of the system in the vicinity of the interface. In particular,
we recover the logarithmic divergence of the thickness of the disordered layer
as the bulk transition is approached, we calculate the critical behavior of the
maxima of the layer susceptibilities, and demonstrate that it is in reasonable
agreement with the simulation data. Directly at the (110) surface, the theory
predicts that all order parameters vanish continuously at the surface with a
nonuniversal, but common critical exponent. However, we find different
exponents for the order parameter of the DO3 phase and the order parameter of
the B2 phase. Using the effective interface model, we derive the finite size
scaling function for the surface order parameter and show that the theory
accounts well for the finite size behavior of the DO3 ordering but not for that
of B2 ordering. The situation is even more complicated in the neighborhood of
the (100) surface, due to the presence of an ordering field which couples to
the B2 order.

</DOC>
<DOC>
<DOCNO> 170057 </DOCNO>
Controlled Quantum Teleportaion


  A theoretical scheme for controlled quantum teleportation is presented, using
the entanglement property of GHZ state.

</DOC>
<DOC>
<DOCNO> 102110 </DOCNO>
Springer theory in braid groups and the Birman-Ko-Lee monoid


  We state a conjecture about centralizers of certain roots of central elements
in braid groups, and check it for Artin braid groups and some other cases. Our
proof makes use of results by Birman-Ko-Lee; we give a new intrinsic account of
these results.

</DOC>
<DOC>
<DOCNO> 120716 </DOCNO>
Solar Oscillations and Convection: II. Excitation of Radial Oscillations


  Solar p-mode oscillations are excited by the work of stochastic,
non-adiabatic, pressure fluctuations on the compressive modes. We evaluate the
expression for the radial mode excitation rate derived by Nordlund and Stein
(Paper I) using numerical simulations of near surface solar convection. We
first apply this expression to the three radial modes of the simulation and
obtain good agreement between the predicted excitation rate and the actual mode
damping rates as determined from their energies and the widths of their
resolved spectral profiles. We then apply this expression for the mode
excitation rate to the solar modes and obtain excellent agreement with the low
l damping rates determined from GOLF data. Excitation occurs close to the
surface, mainly in the intergranular lanes and near the boundaries of granules
(where turbulence and radiative cooling are large). The non-adiabatic pressure
fluctuations near the surface are produced by small instantaneous local
imbalances between the divergence of the radiative and convective fluxes near
the solar surface. Below the surface, the non-adiabatic pressure fluctuations
are produced primarily by turbulent pressure fluctuations (Reynolds stresses).
The frequency dependence of the mode excitation is due to effects of the mode
structure and the pressure fluctuation spectrum. Excitation is small at low
frequencies due to mode properties -- the mode compression decreases and the
mode mass increases at low frequency. Excitation is small at high frequencies
due to the pressure fluctuation spectrum -- pressure fluctuations become small
at high frequencies because they are due to convection which is a long time
scale phenomena compared to the dominant p-mode periods.

</DOC>
<DOC>
<DOCNO> 8593 </DOCNO>
Excitonic order at strong-coupling: pseudo-spins, doping, and


  A tight binding model is introduced to describe the strong interaction limit
of excitonic ordering. At stoichiometry, the model reduces in the strong
coupling limit to a pseudo-spin model with approximate U(4) symmetry. Excitonic
order appears in the pseudo-spin model as in-plane pseudo-magnetism. The U(4)
symmetry unifies all possible singlet and triplet order parameters describing
such states. Super-exchange, Hunds-rule coupling, and other perturbations act
as anisotropies splitting the U(4) manifold, ultimately stabilizing a
paramagnetic triplet state. The tendency to ferromagnetism with doping
(observed experimentally in the hexaborides) is explained as a spin-flop
transition to a different orientation of the U(4) order parameter. The physical
mechanism favoring such a reorientation is the enhanced coherence (and hence
lower kinetic energy) of the doped electrons in a ferromagnetic background
relative to the paramagnet. A discussion of the physical meaning of various
excitonic states and their experimental consequences is also provided.

</DOC>
<DOC>
<DOCNO> 71700 </DOCNO>
Pion and Kaon Vector Form Factors: a Chiral Unitary Approach


  The pion and kaon coupled-channel vector form factors are described by making
use of the resonance chiral Lagrangian results together with a suitable
unitarization method in order to take care of the final state interactions. A
very good reproduction of experimental data is accomplished for the vector form
factors up to $\sqrt{s}\leq 1.2$ GeV and for the $\pi\pi$ P-wave phase shifts
up to $\sqrt{s}\leq 1.5$ GeV.

</DOC>
<DOC>
<DOCNO> 13573 </DOCNO>
Quantum state engineering with Josephson-junction devices


  We review recent theoretical and experimental progress in quantum state
engineering with Josephson junction devices. The concepts of quantum computing
have stimulated an increased activity in the field. Either charges or phases
(fluxes) of the Josephson systems can be used as quantum degrees of freedom,
and their quantum state can be manipulated coherently by voltage and current
pulses. They thus can serve as qubits, and quantum logic gates can be
performed. Their phase coherence time, which is limited, e.g., by the
electromagnetic fluctuations in the control circuit, is long enough to allow a
series of these manipulations. The quantum measurement process performed by a
single-electron transistor, a SQUID, or further nanoelectronic devices is
analyzed in detail.

</DOC>
<DOC>
<DOCNO> 178979 </DOCNO>
Quark Models of Baryon Masses and Decays


  The description of baryon resonance masses and decays in the constituent
quark model is outlined, with emphasis on the potential-model approach combined
with the 3P0 pair-creation model of strong decays. This approach allows the
estimation of branching fractions for baryon states missing in pion nucleon
elastic scattering analyses but expected to be present in electromagnetic
production. Prospects for the discovery of hybrid baryons are discussed. A
subjective list of the most important corrections required to this approach is
presented.

</DOC>
<DOC>
<DOCNO> 170091 </DOCNO>
Geometry of entangled states


  Geometric properties of the set of quantum entangled states are investigated.
We propose an explicit method to compute the dimension of local orbits for any
mixed state of the general K x M problem and characterize the set of
effectively different states (which cannot be related by local
transformations). Thus we generalize earlier results obtained for the simplest
2 x 2 system, which lead to a stratification of the 6D set of N=4 pure states.
We define the concept of absolutely separable states, for which all globally
equivalent states are separable.

</DOC>
<DOC>
<DOCNO> 174461 </DOCNO>
Inhomogeneous isospin distribution in the reactions of 28Si + 112Sn and


  We have created quasiprojectiles of varying isospin via peripheral reactions
of 28Si + 112Sn and 124Sn at 30 and 50 MeV/nucleon. The quasiprojectiles have
been reconstructed from completely isotopically identified fragments. The
difference in N/Z of the reconstructed quasiprojectiles allows the
investigation of the disassembly as a function of the isospin of the
fragmenting system. The isobaric yield ratio 3H/3He depends strongly on N/Z
ratio of quasiprojectiles. The dependences of mean fragment multiplicity and
mean N/Z ratio of the fragments on N/Z ratio of the quasiprojectile are
different for light charged particles and intermediate mass fragments.
Observation of a different N/Z ratio of light charged particles and
intermediate mass fragments is consistent with an inhomogeneous distribution of
isospin in the fragmenting system.

</DOC>
<DOC>
<DOCNO> 122065 </DOCNO>
HD172481: a super lithium-rich metal-deficient post-AGB binary with a


  We present in this paper a study on the peculiar supergiant HD172481. Its
spectral type (F2Ia), high galactic latitude (b=-10.37), circumstellar dust,
high radial velocity and moderate metal deficiency ([Fe/H]=-0.55) confirm the
post-AGB character of this object. A detailed chemical analysis shows slight
but real s-process overabundances, however no CNO-enhancement was detected.
Furthermore, the spectral energy distribution and the TiO bands in the red part
of the spectrum reveal a red luminous companion. The luminosity ratio of the
hot F type component and this cool M type companion L(F)/L(M) is derived for a
reddening of E(B-V)=0.44 (L(F)/L(M)=1.8) and indicates that the companion must
also be strongly evolved and probably evolving along the AGB. Neither our
photometric data-set, nor our radial velocity monitoring show evidence for
orbital variability which may indicate that the period is too large for direct
binary interaction. Most interestingly, a strong lithium resonance line is
detected, which yields an abundance of log(Li)=3.6. Several explanations for
this large lithium content are explored.

</DOC>
<DOC>
<DOCNO> 121157 </DOCNO>
Asteroseismology for the Masses


  For many years, astronomers interested in white dwarf stars have promised
that the study of these relatively simple compact objects would ultimately lead
to useful information about the physics under extreme conditions of temperature
and pressure. We are finally ready to make good on that promise. Using the
observational techniques of the Whole Earth Telescope developed over the past
decade, and a new analytical method only recently made feasible by the
availability of fast inexpensive computers, we demonstrate that meaningful
constraints can now be made on the rates of important nuclear fusion reactions
which cannot presently be measured in the laboratory.

</DOC>
<DOC>
<DOCNO> 68295 </DOCNO>
Cosmic Neutrinos and New Physics beyond the Electroweak Scale


  New physics beyond the electroweak scale may increase weak interaction cross
sections beyond the Standard Model predictions. Such cross sections can be
expected within theories that solve the hierarchy problem of known interactions
with a unification scale in the TeV range. We derive constraints on these cross
sections from the flux of neutrinos expected from cosmic ray interactions with
the microwave background and the non-observation of horizontal air showers. We
also discuss how this limit can be improved by upcoming cosmic ray and neutrino
experiments, and how the energy dependence of the new interactions can be
probed by these experiments.

</DOC>
<DOC>
<DOCNO> 8938 </DOCNO>
Structural properties and quasiparticule energies of cubic SrO, MgO and


  The structural properties and the band structures of the charge-transfer
insulating oxides SrO, MgO and SrTiO3 are computed both within density
functional theory in the local density approximation (LDA) and in the Hedin's
GW scheme for self-energy corrections, by using a model dielectric function,
which approximately includes local field and dynamical effects. The deep
valence states are shifted by the GW method to higher binding energies, in very
good agreement with photoemission spectra. Since in all of these oxides the
direct gaps at high-symmetry points of the Brillouin zone may be very sensitive
to the actual value of the lattice parameter a, already at the LDA level,
self-energy corrections are computed both at the theoretical and the
experimental a. For MgO and SrO, the values of the transition energies between
the valence and the conduction bands are improved by GW corrections, while for
SrTiO3 they are overestimated. The results are discussed in relation to the
importance of local field effects and to the nature of the electronic states in
these insulating oxides.

</DOC>
<DOC>
<DOCNO> 100585 </DOCNO>
Grassmannians of secant varieties


  For an irreducible projective variety X, we study the family of h-planes
contained in the secant variety Sec_k(X), for 0<h<k. These families have an
expected dimension and we study varieties for which the expected dimension is
not attained; for these varieties, making general consecutive projections to
lower dimensional spaces, we do not get the expected singularities. In
particular, we examine the family G of lines sitting in 3-secant planes to a
surface S. We show that the actual dimension of G is equal to the expected
dimension unless S is a cone or a rational normal scroll of degree 4 in P^5.

</DOC>
<DOC>
<DOCNO> 170020 </DOCNO>
Fulfillment of expectations of precise measurements of the Casimir force


  We compare theoretical expectations for the Casimir force with the results of
precise measurements. The force is calculated at finite temperature for
multilayered covering of the bodies using the Lifshitz theory. We argue that
the dielectric function of the metallization has to be directly measured to
reach the necessary precision in the force calculation. Without knowledge of
this function one can establish a well defined upper limit on the force using
parameters of perfect single-crystal materials. The force measured in the
torsion pendulum experiment does not contradict to the upper limit. Importance
of a thin Au/Pd layer in the atomic force microscope experiments is stressed.
The force measured with the microscope is larger than the upper limit at small
separations between bodies. The discrepancy is significant and reproduced for
both performed measurements. The origin of the discrepancy is discussed. The
simplest modification of the experiment is proposed allowing to make its
results more reliable and answer the question if the discrepancy has any
relation with the existence of a new force.

</DOC>
<DOC>
<DOCNO> 120121 </DOCNO>
Looking Back with Neutrinos


  We briefly discuss the history of suggestions for time- of-flight effects due
to non-zero neutrino mass and a recent proposal that such effects can be used
to determine the parameters of cosmology. With neutrinos there is potentially a
much deeper ``look back time'' than with photons. We note a new point, that if
future large scale neutrino detection arrays see long-time secular variations
in counting rate, this could be due to highly redshifted bursts originating in
the early universe.

</DOC>
<DOC>
<DOCNO> 11111 </DOCNO>
The decoherence criterion


  The decoherence mechanism signals the limits beyond which the system dynamics
approaches the classical behavior. We show that in some cases decoherence may
also signal the limits beyond which the system dynamics has to be described by
quantum field theory, rather than by quantum mechanics.

</DOC>
<DOC>
<DOCNO> 80895 </DOCNO>
Wigner Functions on a Lattice


  The Wigner functions on the one dimensional lattice are studied. Contrary to
the previous claim in literature, Wigner functions exist on the lattice with
any number of sites, whether it is even or odd. There are infinitely many
solutions satisfying the conditions which reasonable Wigner functions should
respect. After presenting a heuristic method to obtain Wigner functions, we
give the general form of the solutions. Quantum mechanical expectation values
in terms of Wigner functions are also discussed.

</DOC>
<DOC>
<DOCNO> 40126 </DOCNO>
A Search for $B\to \tau\nu$


  We report results of a search for $B\to\tau\nu$ in a sample of 9.7 million
charged $B$ meson decays. The search uses both $\pi\nu$ and $\ell\nu\bar\nu$
decay modes of the $\tau$, and demands exclusive reconstruction of the
companion $\bar B$ decay to suppress background. We set an upper limit on the
branching fraction ${\cal B}(B\to \tau\nu) < 8.4\times 10^{-4}$ at 90%
confidence level. With slight modification to the analysis we also establish
${\cal B}(B^\pm\to K^\pm\nu\bar\nu) < 2.4\times 10^{-4}$ at 90% confidence
level.

</DOC>
<DOC>
<DOCNO> 68535 </DOCNO>
Fragmentation Functions from Flavour-inclusive and Flavour-tagged e^+e^-


  Fitting $Z^0$-pole data from ALEPH and SLD, and TPC data at a lower c.m.s.\
energy, we fix the boundary condition for NLO parton$\to$hadron
(hadron$=\pi^\pm, K^\pm, \sum_h h^\pm$) fragmentation functions (FFs) at the
low resolution scale of the radiative parton model of Gl\"{u}ck, Reya and Vogt
(GRV). Perturbative LO$\leftrightarrow$NLO stability is investigated. The
emphasis of the fit is on information on the fragmentation process for
individual light ($u,d,s$) and heavy ($c,b$) quark flavours where we comment on
the factorization scheme for heavy quarks in $e^+e^-$ annihilations as compared
to deep inelastic production. Inasmuch as the light quark input parameters are
not yet completely pinned down by measurements we assume power laws to
implement a physical hierarchy among the FFs respecting valence enhancement and
strangeness suppression both of which are manifest from recent leading particle
measurements. Through the second Mellin moments of the input functions we
discuss the energy-momentum sum rule for massless FFs. We discuss our results
in comparison to previous fits and recent 3-jet measurements and formulate
present uncertainties in our knowledge of the individual FFs.

</DOC>
<DOC>
<DOCNO> 120852 </DOCNO>
Young massive star clusters in M51


  A search for young massive star clusters (YMCs) in the nearby face-on spiral
galaxy M51 (NGC 5194) has been carried out using UBV CCD images from the prime
focus camera on the Lick 3 meter Shane telescope. The YMC population is found
to be quite rich with a specific U-band luminosity T_L(U) = 1.4, consistent
with the high current star formation rate of this galaxy. The brightest
clusters have M_V about -12.5, far brighter than any young clusters currently
known in the Milky Way and even surpassing the luminosity of the R136 cluster
in the 30 Dor complex in the Large Magellanic Cloud. A few of the YMCs are
examined on archive HST/WFPC2 images, confirming their cluster nature and
providing estimates of their effective radii of 2-3 pc. The number of YMCs in
M51 is compatible with extrapolation of a power-law luminosity function with
exponent roughly equal to -2 from a Milky Way-like population of open clusters.
Both the SFR and T_L(U) of M51 are similar to those of other cluster-rich
spiral galaxies like NGC 1313 and M83.

</DOC>
<DOC>
<DOCNO> 14100 </DOCNO>
Self-Assembled InAs Quantum Dots on Patterned InP Substrates


  The size distribution of self-assembled InAs quantum dots grown on (001) InP
under the Stranski-Krastanow growth mode is controlled using selective
area/chemical beam epitaxy, which allows the formation of quantum dots at
specific locations. As the dimensions of the patterned areas are decreased from
1000 nm down to 50 nm or less, scanning electron microscopy reveals a gradual
increase in the spatial correlation between quantum dots, which leads to the
formation of ordered arrays for dimensions below 200 nm.

</DOC>
<DOC>
<DOCNO> 170151 </DOCNO>
Finding Matches between Two Databases on a Quantum Computer


  Given two unsorted lists each of length N that have a single common entry, a
quantum computer can find that matching element with a work factor of
$O(N^{3/4}\log N)$ (measured in quantum memory accesses and accesses to each
list). The amount of quantum memory required is $O(N^{1/2})$. The quantum
algorithm that accomplishes this consists of an inner Grover search combined
with a partial sort all sitting inside of an outer Grover search.

</DOC>
<DOC>
<DOCNO> 7647 </DOCNO>
Study of Ce intermetallic compounds: an LDA classification and


  Spin-polarized calculations within the LDA approximation have been done with
the goal of characterizing Ce intermetallic compounds. Symmetry and chemical
environment effects on 4f hybridization and, thereafter, on magnetization
effects have been studied.

</DOC>
<DOC>
<DOCNO> 40302 </DOCNO>
Photon Structure and Quantum Fluctuation


  Photon structure derives from quantum fluctuation in quantum field theory to
fermion and anti-fermion, and has been an experimentally established feature of
electrodynamics since the discovery of the positron. In hadronic physics, the
observation of factorisable photon structure is similarly a fundamental test of
the quantum field theory Quantum Chromodynamics (QCD). An overview of
measurements of hadronic photon structure in e+e- and ep interactions is
presented, and comparison made with theoretical expectation, drawing on the
essential features of photon fluctuation into quark and anti-quark in QCD.

</DOC>
<DOC>
<DOCNO> 117393 </DOCNO>
2-D Radiation Transfer Model of Non-Spherically Symmetric Dust Shell in


  We have fitted the HST images and the spectral energy distributions (SEDs) of
three proto-planetary nebulae (PPN) with a 2-D radiation transfer model. The
geometric and mass loss properties of these PPN are also derived.

</DOC>
<DOC>
<DOCNO> 67745 </DOCNO>
Resummation of Nonalternating Divergent Perturbative Expansions


  A method for the resummation of nonalternating divergent perturbation series
is described. The procedure constitutes a generalization of the Borel-Pad\'{e}
method. Of crucial importance is a special integration contour in the complex
plane. Nonperturbative imaginary contributions can be inferred from the purely
real perturbative coefficients. A connection is drawn from the quantum field
theoretic problem of resummation to divergent perturbative expansions in other
areas of physics.

</DOC>
<DOC>
<DOCNO> 120429 </DOCNO>
High spatial resolution observations of CUDSS14A: a SCUBA-selected


  We present a high-resolution millimetre interferometric image of the
brightest SCUBA-selected galaxy from the Canada-UK deep SCUBA survey (CUDSS).
We make a very clear detection at 1.3 mm, but fail to resolve any structure in
the source. The interferometric position is within 1.5 arcsec of the SCUBA 850
$\mu$m centroid, and also within 1.5 arcsec of a 44 $\mu$Jy radio source and a
very faint, extremely red galaxy which we had previously identified as the
submillimetre source. We also present new optical and infrared imaging, and
infrared spectroscopy of this source. We model the overall spectral energy
distribution and conclude that it lies within the redshift range 2$< z < 4.5$.
The submm/FIR luminosity of CUDSS14A is very weakly dependent on redshift
within the constrained range, and is roughly 4$\times10^{12}$ L$_\odot$ (for
H$_0$=75 and an assumed Arp220-like spectrum), which implies a star-formation
rate $\sim$1000 M$_\odot$ yr$^{-1}$. We derive an approximate gas mass of $\sim
10^{10}$ M$_\odot$ which would imply the current star-forming activity cannot
be sustained for longer than about 10 million years. With the present data
however we are unable to rule out a significant AGN contribution to the total
luminosity.

</DOC>
<DOC>
<DOCNO> 70936 </DOCNO>
Formation of Quarkonium States at RHIC


  At RHIC the cross section for c-cbar production will be large enough such
that approximately 10 pairs will be produced in each central collision. If a
region of deconfined quarks and gluons is subsequently formed, one would expect
that the mobility of the charm quarks will enable them to form J/Psi through
"off-diagonal" combinations, involving a quark and an antiquark which were
originally produced in separate incoherent interactions. We present model
estimates of this effect, which indicate that the signal for deconfinement at
RHIC may possibly be J/Psi enhancement rather than suppression.

</DOC>
<DOC>
<DOCNO> 12166 </DOCNO>
Bilayer Quantum Hall Systems: Spin-Pseudospin Symmetry Breaking and


  We discuss and review recent advances in our understaning of quantum Hall
systems where additional quantum numbers associated with spin and/or layer
(pseudospin) indices play crucial roles in creating exotic quantum phases.
Among the novel quantum phases we discuss are the recently discovered canted
antiferromagnetic phase, the spontaneous interlayer coherent phase, and various
spin Bose glass phases. We describe the theoretical models used in studying
these novel phases and the various experimental techniques being used to search
for these phases. Both zero temperature quantum phase transitions and finite
temperature phase transitions are discussed. Emphasis in this article is on the
recent developments in novel quantum phases and quantum phase transitions in
bilayer quantum Hall systems where nontrivial magnetic ground states associated
with spontaneous spin symmetry breaking play central role.

</DOC>
<DOC>
<DOCNO> 99400 </DOCNO>
Normal del Pezzo surfaces containing a nonrational singularity


  Working over a perfect field, I classify normal del Pezzo surfaces with base
number one that contain a nonrational singularity. They form a huge infinite
hierarchy; contractions of ruled surfaces lie on top of it. Descending the
hierarchy hinges on a generalized version of elementary transformations. As an
application, I determine the structure of 2-dimensional anticanonical models
for arbitrary normal surfaces.

</DOC>
<DOC>
<DOCNO> 40109 </DOCNO>
Two Higgs Doublet Model and Model Independent Interpretation of Neutral


  Searches for the neutral Higgs bosons h0 and A0, are used to obtain limits on
the Type II Two Higgs Doublet Model (2HDM(II)) with no CP-violation in the
Higgs sector and no additional particles besides the five Higgs bosons. The
analysis combines approximately 170 pb-1 of data collected with the OPAL
detector at sqrt{s} ~ 189 GeV with previous runs at sqrt{s} ~ mZ and sqrt{s} ~
183 GeV. The searches are sensitive to the h0, A0 -> qq, gg, tau+tau- and h0 ->
A0A0 decay modes of the Higgs bosons. For the first time, the 2HDM(II)
parameter space is explored in a detailed scan, and new flavour independent
analyses are applied to examine regions in which the neutral Higgs bosons decay
predominantly into light quarks or gluons. Model-independent limits are also
given.

</DOC>
<DOC>
<DOCNO> 116913 </DOCNO>
A New Linear Inductive Voltage Adder Driver for the Saturn Accelerator


  Saturn is a dual-purpose accelerator. It can be operated as a large-area
flash x-ray source for simulation testing or as a Z-pinch driver especially for
K-line x-ray production. In the first mode, the accelerator is fitted with
three concentric-ring 2-MV electron diodes, while in the Z-pinch mode the
current of all the modules is combined via a post-hole convolute arrangement
and driven through a cylindrical array of very fine wires. We present here a
point design for a new Saturn class driver based on a number of linear
inductive voltage adders connected in parallel. A technology recently
implemented at the Institute of High Current Electronics in Tomsk (Russia) is
being utilized[1].
  In the present design we eliminate Marx generators and pulse-forming
networks. Each inductive voltage adder cavity is directly fed by a number of
fast 100-kV small-size capacitors arranged in a circular array around each
accelerating gap. The number of capacitors connected in parallel to each cavity
defines the total maximum current. By selecting low inductance switches,
voltage pulses as short as 30-50-ns FWHM can be directly achieved.

</DOC>
<DOC>
<DOCNO> 120891 </DOCNO>
Is the deficit of z > 1 field ellipticals real ?


  The results of a 700 arcmin^2 survey for EROs are presented. The sky
distribution of EROs is very inhomogeneous and their two point correlation
function shows a very high amplitude, a factor of 10 larger than that of the
field galaxy population. Such a clustering can explain the strong variance
found in previous works, and provides evidence that ERO are mostly made of
high-z ellipticals. The surface density of EROs found in our large survey is in
good agreement with that expected for passively evolving ellipticals formed at
high redshift (z\simgt2.5).

</DOC>
<DOC>
<DOCNO> 9893 </DOCNO>
Microscopic Charge Inhomogeneities in Underdoped La_2-xSr_xCuO_4: Local


  We present local structural evidence for the existence of charge
inhomogeneities at low temperature in underdoped and optimally doped
La_2-xSr_xCuO_4. The inhomogeneities disappear for x > 0.2. The evidence for
the charge inhomogeneities comes from an anomalous increase in the in-plane
Cu-O bond length distribution in the underdoped samples as well as evidence for
CuO_6 octahedral tilt inhomogeneities in the intermediate range structure.
Preliminary analysis of the temperature dependence of this phenomenon indicates
that the inhomogeneities set in at temperatures in the range 60 K < Tco < 130 K
which depends on doping.

</DOC>
<DOC>
<DOCNO> 151083 </DOCNO>
Strings in Background Electric Field, Space/Time Noncommutativity and A


  Searching for space/time noncommutativity we reconsider open strings in a
constant background electric field. The main difference between this situation
and its magnetic counterpart is that here there is a critical electric field
beyond which the theory does not make sense. We show that this critical field
prevents us from finding a limit in which the theory becomes a field theory on
a noncommutative spacetime. However, an appropriate limit toward the critical
field leads to a novel noncritical string theory on a noncommutative spacetime.

</DOC>
<DOC>
<DOCNO> 72036 </DOCNO>
Baryons as Relativistic Bound States of Quark and Diquark


  In this thesis a model framework for describing baryons as diquark-quark
bound states is presented which is formulated in an explicitly covariant
manner. The relativistic bound state problem for three quarks is considered.
Diquarks are introduced as separable correlations in the two-quark correlation
function and thereby baryons are described by a Bethe-Salpeter equation for
bound states of quark and diquark which interact by quark exchange. In analogy
to the meson spectrum, scalar and axialvector diquarks are considered to be the
most important two-quark configurations within baryons. The numerical solutions
of the covariant Bethe-Salpeter equation are subsequently employed in the
calculation of electromagnetic, strong and axial form factors of the nucleons.
The construction of the electromagnetic current operator in the diquark-quark
model respects gauge invariance. Invariance under chiral symmetry
transformations is slightly violated for vector diquarks have been neglected,
leading to a modest violation of the Goldberger-Treiman relation. The
possibility of an effective parametrization of confinement by suitable
modifications of the quark and diquark propagators is investigated. It is shown
that the modelling of confinement chosen here is suitable for the calculation
of the octet and devuplet spectrum and spacelike nucleon properties, but its
applicability breaks down for processes where large energies are transferred to
the nucleon as it is the case in certain meson production processes. Model
solutions for nucleon wave functions and observables are compared between the
full relativistic treatment and a widely used semi-relativistic approximation.
The considerable deviations in the results illustrate the inadequacy of
employing the semi-relativistic treatment.

</DOC>
<DOC>
<DOCNO> 121373 </DOCNO>
The Galactic Disk Distribution of Planetary Nebulae with Warm Dust


  Can the distribution of warm-dust compositions in IR-bright galactic disk PNe
be linked to the underlying stellar population? The PNe with warm dust emission
represent a homogeneous population, which is presumably young and minimally
affected by a possible dependence of PN lifetime on progenitor mass. The sample
in paper I thus allows testing the predictions of single star evolution,
through a comparison with synthetic distributions and under the assumption that
tip-of-the-AGB and PN statistics are similar. We construct a schematic model
for AGB evolution (adapted from Groenewegen & de Jong 1993), whose
free-parameters are calibrated with the luminosity function (LF) of C stars in
the LMC, the initial-final mass relation, and the range of PN compositions. The
observed metallicity gradient and distribution of star forming regions with
galactocentric radius (Bronfman et al. 2000) allow us to synthesise the
galactic disk PN progenitor population. We find the fraction of O-rich PNe,
f(O), is a tight constraint on AGB parameters. For our best model, a minimum PN
progenitor mass Mmin=1Msun predicts that about 50% of all young PNe should be
O-rich, compared to an observed fraction of 22%; thus Mmin=1.2Msun, at a 2sigma
confidence level. By contrast, current AGB models for single stars can account
neither for the continuous range of N enrichment (Leisy & Dennefeld 1996), nor
for the observation that the majority of very C-rich PNe have Peimbert type I
(paper I). f(O) is thus an observable much easier to model. The decrease in
f(O) with galactocentric radius, as reported in paper I, is a strong property
of the synthetic distribution, independent of Mmin. This trend reflects the
sensitivity of the surface temperature of AGB stars and of the core mass at the
first thermal pulse to the galactic metallicity gradient.

</DOC>
<DOC>
<DOCNO> 119112 </DOCNO>
Mitigating Charge Transfer Inefficiency in the Chandra X-ray


  The ACIS front-illuminated CCDs onboard the Chandra X-ray Observatory were
damaged in the extreme environment of the Earth's radiation belts, resulting in
enhanced charge transfer inefficiency (CTI). This produces a row dependence in
gain, event grade, and energy resolution. We model the CTI as a function of
input photon energy, including the effects of de-trapping (charge trailing),
shielding within an event (charge in the leading pixels of the 3X3 event island
protect the rest of the island by filling traps), and non-uniform spatial
distribution of traps. This technique cannot fully recover the degraded energy
resolution, but it reduces the position dependence of gain and grade
distributions. By correcting the grade distributions as well as the event
amplitudes, we can improve the instrument's quantum efficiency. We outline our
model for CTI correction and discuss how the corrector can improve
astrophysical results derived from ACIS data.

</DOC>
<DOC>
<DOCNO> 170576 </DOCNO>
Complete controllability of quantum systems


  Sufficient conditions for complete controllability of $N$-level quantum
systems subject to a single control pulse that addresses multiple allowed
transitions concurrently are established. The results are applied in particular
to Morse and harmonic-oscillator systems, as well as some systems with
degenerate energy levels. Morse and harmonic oscillators serve as models for
molecular bonds, and the standard control approach of using a sequence of
frequency-selective pulses to address a single transition at a time is either
not applicable or only of limited utility for such systems.

</DOC>
<DOC>
<DOCNO> 102814 </DOCNO>
Polyomino convolutions and tiling problems


  We define a convolution operation on the set of polyominoes and use it to
obtain a criterion for a given polyomino not to tile the plane (rotations and
translations allowed). We apply the criterion to several families of
polyominoes, and show that the criterion detects some cases that are not
detectable by generalized coloring arguments.

</DOC>
<DOC>
<DOCNO> 151516 </DOCNO>
Holography in Superspace


  The AdS/CFT correspondence identifies the coordinates of the conformal
boundary of anti-de Sitter space with the coordinates of the conformal field
theory. We generalize this identification to theories formulated in superspace.
As an application of our results, we study a class of Wilson loops in N=4 SYM
theory. A gauge theory computation shows that the expectation values of these
loops are invariant under a local kappa-symmetry, except at intersections. We
identify this with the kappa-invariance of the associated string worldsheets in
the corresponding bulk superspace.

</DOC>
<DOC>
<DOCNO> 101239 </DOCNO>
Operational quantum logic: An overview


  The term quantum logic has different connotations for different people,
having been considered as everything from a metaphysical attack on classical
reasoning to an exercise in abstract algebra. Our aim here is to give a uniform
presentation of what we call operational quantum logic, highlighting both its
concrete physical origins and its purely mathematical structure. To orient
readers new to this subject, we shall recount some of the historical
development of quantum logic, attempting to show how the physical and
mathematical sides of the subject have influenced and enriched one another.

</DOC>
<DOC>
<DOCNO> 102489 </DOCNO>
GCH implies the existence of many rigid almost free abelian groups


  We begin with the existence of groups with trivial duals for cardinals
aleph_n (n in omega). Then we derive results about strongly aleph_n-free
abelian groups of cardinality aleph_n (n in omega) with prescribed free,
countable endomorphism ring. Finally we use combinatorial results of [Sh:108],
[Sh:141] to give similar answers for cardinals >aleph_omega. As in Magidor and
Shelah [MgSh:204], a paper concerned with the existence of kappa-free, non-free
abelian groups of cardinality kappa, the induction argument breaks down at
aleph_omega. Recall that aleph_omega is the first singular cardinal and such
groups of cardinality aleph_omega do not exist by the well-known Singular
Compactness Theorem (see [Sh:52]).

</DOC>
<DOC>
<DOCNO> 69993 </DOCNO>
Neutrino Zero Modes on Electroweak Strings


  Zero modes of massive standard model fermions have been found on electroweak
Z-strings. A zero mode solution for a massless left-handed neutrino is also
known, but was thought to be non-normalizable. Here we show that although this
mode is not discretely normalizable, it is delta-function normalizable and the
correct interpretation of this solution is within the framework of the
continuum spectrum. We also analyze an extension of the standard model
including right-handed neutrinos in which neutrinos have Dirac masses, arising
from a Yukawa coupling to the usual SU(2) Higgs doublet, and right-handed
Majorana masses. The Majorana mass terms are taken to be spatially homogeneous
and are presumed to arise from the vacuum expectation value of some field
acquired in a phase transition well above the electroweak phase transition. The
resulting zero energy equations have a discrete zero mode.

</DOC>
<DOC>
<DOCNO> 102243 </DOCNO>
Diffusion Effects on the Breakdown of a Linear Amplifier Model Driven by


  We investigate solutions to the equation $\partial_t{\cal E} - {\cal D}\Delta
{\cal E} = \lambda S^2{\cal E}$, where $S(x,t)$ is a Gaussian stochastic field
with covariance $C(x-x',t,t')$, and $x\in {\mathbb R}^d$. It is shown that the
coupling $\lambda_{cN}(t)$ at which the $N$-th moment $<{\cal E}^N(x,t)>$
diverges at time $t$, is always less or equal for ${\cal D}>0$ than for ${\cal
D}=0$. Equality holds under some reasonable assumptions on $C$ and, in this
case, $\lambda_{cN}(t)=N\lambda_c(t)$ where $\lambda_c(t)$ is the value of
$\lambda$ at which $<\exp\lbrack \lambda\int_0^tS^2(0,s)ds\rbrack>$ diverges.
The ${\cal D}=0$ case is solved for a class of $S$. The dependence of
$\lambda_{cN}(t)$ on $d$ is analyzed. Similar behavior is conjectured when
diffusion is replaced by diffraction, ${\cal D}\to i{\cal D}$, the case of
interest for backscattering instabilities in laser-plasma interaction.

</DOC>
<DOC>
<DOCNO> 178441 </DOCNO>
Nuclear quasi-molecular states in ternary fission


  A three-center phenomenological model, able to explain qualitatively the
recently obtained experimental results concerning the quasimolecular stage of a
light-particle accompanied fission process, was developed. A new minimum of a
short-lived molecular state appears in the deformation energy at a separation
distance very close to the touching point. The influence of the shell effects
is discussed. The half-lives of some quasimolecular states which could be
formed in the ^{10}Be and ^{12}C accompanied fission of ^{252}Cf are roughly
estimated to be the order of 1ns, and 1 ms, respectively.

</DOC>
<DOC>
<DOCNO> 117456 </DOCNO>
Giant protostellar outflows revealed by infrared imaging


  We present new infrared data from a survey for embedded protostellar jets in
the Orion A cloud. This survey makes use of the S(1) v = 1-0 line of molecular
hydrogen at lambda = 2.12 mum to search for infrared jets deep inside the cloud
and thus hidden from view at optical wavelengths. We present data on the three
flows associated with the Herbig-Haro objects HH 43/38 & HH 64, HH 65, and the
L1641-N giant flow. HH 43, HH 38 and HH 64 are part of one H_2 flow extending
over at least 1.4 pc. We identify a deeply embedded 1.3 mm and IRAS source (HH
43 MMS1 = IRAS 05355-0709C) as the likely driving source, while the infrared
source previously assumed to drive HH 43/38 (HH 43-IRS1 = IRAS 05357-0710) is
seen to drive a smaller jet. The morphology of HH 43-IRS1 suggests that it is a
star+disk system seen close to edge-on. We identify another large H_2 flow
apparently comprising the L1641-S3 CO outflow and the redshifted lobe of the
L1641-S CO outflow containing HH 65. This flow extends over at least 2.6 pc and
appears strongly curved. It is driven by L1641-S3 IRS, a deeply embedded 1.3 mm
and IRAS source (L1641-S3 MMS1 = IRAS 05375-0731). Finally, we have found some
additional large H_2 features to the east of V 380 Ori and the HH 1/2 system,
which probably outline another part of the L1641-N outflow. The molecular flow
MB 20/21, which extends to the south from V 380 Ori, also appears to be a part
of the L1641-N outflow.

</DOC>
<DOC>
<DOCNO> 122491 </DOCNO>
The X-ray sources at the center of the supernova remnant RXJ0852.0-4622


  We present a BeppoSAX observation of the X-ray source AX J0851.9-4617.4 that
has been proposed as the neutron star associated to the shell like-supernova
remnant RX J0852.0-4622. The image at E>5 keV shows the presence of a new
source, SAX J0852.0-4615, not resolved from AX J0851.9-4617.4 in previous
observations. The improved positional accuracy obtained for AX J0851.9-4617.4
confirms its possible identification with an early type star, also consistent
with its soft thermal spectrum (kT~1.3 keV). SAX J0852.0-4615, with a harder
X-ray spectrum and a higher X-ray to optical flux ratio, is a more likely
candidate for the neutron star associated to the supernova remnant.

</DOC>
<DOC>
<DOCNO> 12810 </DOCNO>
Multiexciton molecules in the hexaborides


  We investigate multiexciton bound states in a semiconducting phase of
divalent hexaborides. Due to three degenerate valleys in both the conduction
and valence bands the binding energy of a 6-exciton molecule is greatly
enhanced by the shell effect. The ground state energies of multiexciton
molecules are calculated using the density functional formalism. We also show
that charged impurities stabilize multiexciton complexes leading to
condensation of localized excitons. These complexes can act as nucleation
centers of local moments.

</DOC>
<DOC>
<DOCNO> 116875 </DOCNO>
A Super-Conducting Linac Driver for the HFBR


  This paper reports on the feasibility study of a proton Super-Conducting
Linac (SCL) as a driver gor the High-Flux Breader Reactor (HFBR) at Brookhaven
National Laboratory (BNL). The Linac operates in Continuos Wave (CW) mode to
produce an average 10 MW of beam power. The Linac energy is 1.0 GeV. The
average proton beam intensity is 10 mA.

</DOC>
<DOC>
<DOCNO> 10512 </DOCNO>
Field-dependent quantum nucleation of antiferromagnetic bubbles


  The phenomenon of quantum nucleation is studied in a nanometer-scale
antiferromagnet with biaxial symmetry in the presence of a magnetic field at an
arbitrary angle. Within the instanton approach, we calculate the dependence of
the rate of quantum nucleation and the crossover temperature on the orientation
and strength of the field for bulk solids and two-dimensional films of
antiferromagnets, respectively. Our results show that the rate of quantum
nucleation and the crossover temperature from thermal-to-quantum transitions
depend on the orientation and strength of the field distinctly, which can be
tested with the use of existing experimental techniques.

</DOC>
<DOC>
<DOCNO> 118533 </DOCNO>
Gravity-Modes in ZZ Ceti Stars: IV. Amplitude Saturation by Parametric


  ZZ Ceti stars exhibit small amplitude photometric pulsations in multiple
gravity-modes. We demonstrate that parametric instability, a form of resonant
3-mode coupling, limits overstable modes to amplitudes similar to those
observed. In particular, it reproduces the observed trend that longer period
modes have larger amplitudes. Parametric instability involves the
destabilization of a pair of stable daughter modes by an overstable parent
mode. The 3-modes must satisfy exact angular selection rules and approximate
frequency resonance. The lowest instability threshold for each parent mode is
provided by the daughter pair that minimizes
$(\delta\omega^2+\gamma_d^2)/\kappa^2$, where $\kappa$ is the nonlinear
coupling constant, $\delta\omega$ is the frequency mismatch, and $\gamma_d$ is
the energy damping rate of the daughter modes. The overstable mode's amplitude
is maintained at close to the instability threshold value.
  Although parametric instability defines an upper envelope for the amplitudes
of overstable modes in ZZ Ceti stars, other nonlinear mechanisms are required
to account for the irregular distribution of amplitudes of similar modes and
the non-detection of modes with periods longer than $1,200\s$. Resonant 3-mode
interactions involving more than one excited mode may account for the former.
Our leading candidate for the latter is Kelvin-Helmholtz instability of the
mode-driven shear layer below the convection zone.

</DOC>
<DOC>
<DOCNO> 68009 </DOCNO>
Cosmic defects and cosmology


  We provide a pedagogical overview of defect models of structure formation. We
first introduce the concept of topological defect, and describe how to classify
them. We then show how defects might be produced in phase transitions in the
Early Universe and approach non-pathological scaling solutions. A very
heuristic account of structure formation with defects is then provided,
following which we introduce the tool box required for high precision
calculations of CMB and LSS power spectra in these theories. The decomposition
into scalar vector and tensor modes is reviewed, and then we introduce the
concept of unequal-time correlator. We use isotropy and causality to constrain
the form of these correlators. We finally show how these correlators may be
decomposed into eigenmodes, thereby reducing a defect problem to a series of
``inflation'' problems. We conclude with a short description of results in
these theories and how they fare against observations. We finally describe yet
another application of topological defects in cosmology: baryogenesis.

</DOC>
<DOC>
<DOCNO> 40121 </DOCNO>
Determination of the B -> D^*+l-nu Decay Width and |V_{cb}|


  We determine the CKM matrix element |Vcb| using a sample of 3.33 million
BBbar events in the CLEO detector at CESR. We determine the yield of
reconstructed B --> D*+ l nu decays as a function of w = v_B . v_D*, and from
this we obtain the differential decay rate d\Gamma/dw. By extrapolating the
differential decay rate to w=1, the kinematic point at which the D* is at rest
relative to the B, we extract the product |Vcb| F(1), where F(1) is the form
factor at w=1 and is predicted accurately by theory. We find |Vcb| F(1) =
0.0424 +- 0.0018(stat.) +- 0.0019(syst.). We also integrate the differential
decay rate over w to obtain B(B --> D*+ l nu) = (5.66 +- 0.29 +- 0.33)%. All
results are preliminary.

</DOC>
<DOC>
<DOCNO> 10465 </DOCNO>
De Haas-van Alphen effect in two- and quasi two-dimensional metals and


  An analytical form of the quantum magnetization oscillations (de Haas-van
Alphen effect) is derived for two- and quasi two-dimensional metals in normal
and superconducting mixed states. The theory is developed under condition that
the chemical potential is much greater than the cyclotron frequency, which is
proved to be valid for using grand canonical ensemble in the systems of low
dimensionality. Effects of impurity, temperature, spin-splitting and vortex
lattice - in the case of superconductors of type II -, are taken into account.
Contrary to the three dimensional case, the oscillations in sufficiently pure
systems of low dimensionality and at sufficiently low temperatures are
characterized by a saw-tooth wave form, which smoothened with temperature and
concentration of impurities growth. In the normal quasi two-dimensional
systems, the expression for the magnetization oscillations includes an extra
factor expressed through the transfer integral between the layers. The
additional damping effect due to the vortex lattice is found. The criterion of
proximity to the upper critical field for the observation of de Haas-van Alphen
effect in the superconducting mixed state is established.

</DOC>
<DOC>
<DOCNO> 102640 </DOCNO>
Diagonal Sums of Boxed Plane Partitions


  We give a simple proof of a nice formula for the means and covariances of the
diagonal sums of a uniformly random boxed plane parition.

</DOC>
<DOC>
<DOCNO> 150443 </DOCNO>
Unification of spins and charges in Grassmann space and in space of


  Polynomials in Grassmann space can be used to describe all the internal
degrees of freedom of spinors, scalars and vectors, that is their spins and
charges. It was shown that K\"ahler spinors, which are polynomials of
differential forms, can be generalized to describe not only spins of spinors
but also spins of vectors as well as spins and charges of scalars, vectors and
spinors. If the space (ordinary and noncommutative) has 14 dimensions or more,
the appropriate spontaneous break of symmetry leads gravity in $d$ dimensions
to manifest in four dimensional subspace as ordinary gravity and all needed
gauge fields as well as the Yukawa couplings. Both approaches, the K\"ahler's
one (if generalized) and our, manifest four generations of massless fermions,
which are left handed SU(2) doublets and right handed SU(2) singlets. In this
talk a possible way of spontaneously broken symmetries is pointed out on the
level of canonical momentum.

</DOC>
<DOC>
<DOCNO> 121151 </DOCNO>
Electromagnetic Radiation and Motion of Real Particle


  Relativistically covariant equation of motion for real dust particle under
the action of electromagnetic radiation is derived. The particle is neutral in
charge. Equation of motion is expressed in terms of particle's optical
properties, standardly used in optics for stationary particles.

</DOC>
<DOC>
<DOCNO> 178826 </DOCNO>
On the Strength of Spin-Isospin Transitions in A=28 Nuclei


  The relations between the strengths of spin-isospin transition operators
extracted from direct nuclear reactions, magnetic scattering of electrons and
processes of semi-leptonic weak interactions are discussed.

</DOC>
<DOC>
<DOCNO> 70377 </DOCNO>
On the charge radius of the neutrino


  Using the pinch technique we construct at one-loop order a neutrino charge
radius, which is finite, depends neither on the gauge-fixing parameter nor on
the gauge-fixing scheme employed, and is process-independent. This definition
stems solely from an effective proper photon-neutrino one-loop vertex, with no
reference to box or self-energy contributions. The role of the $WW$ box in this
construction is critically examined. In particular it is shown that the
exclusion of the effective WW box from the definition of the neutrino charge
radius is not a matter of convention but is in fact dynamically realized when
the target-fermions are right-handedly polarized. In this way we obtain a
unique decomposition of effective self-energies, vertices, and boxes, which
separately respect electroweak gauge invariance. We elaborate on the tree-level
origin of the mechanism which enforces at one-loop level massive cancellations
among the longitudinal momenta appearing in the Feynman diagrams, and in
particular those associated with the non-abelian character of the theory.
Various issues related to the known connection between the pinch technique and
the Background Field Method are further clarified. Explicit closed expressions
for the neutrino charge radius are reported.

</DOC>
<DOC>
<DOCNO> 85337 </DOCNO>
Thurston's Geometrization Conjecture and cosmological models


  We investigate a class of spatially compact inhomogeneous spacetimes.
Motivated by Thurston's Geometrization Conjecture, we give a formulation for
constructing spatially compact composite spacetimes as solutions for the
Einstein equations. Such composite spacetimes are built from the spatially
compact locally homogeneous vacuum spacetimes which have two commuting Killing
vectors by gluing them through a timelike hypersurface admitting a homogeneous
spatial slice spanned by the commuting Killing vectors. Topology of the spatial
section of the timelike boundary is taken to be the torus. We also assume that
the matter which will arise from the gluing is compressed on the boundary, i.e.
we take the thin-shell approximation. By solving the junction conditions, we
can see dynamical behavior of the connected (composite) spacetime. The
Teichm\"uller deformation of the torus also can be obtained. We apply our
formalism to a concrete model. The relation to the torus sum of 3-manifolds and
the difficulty of this problem are also discussed.

</DOC>
<DOC>
<DOCNO> 68050 </DOCNO>
Bilepton Resonance in Electron-Electron Scattering


  Theoretical backgound for bileptonic gauge bosons is reviewed, both the
SU(15) GUT model and the 3-3-1 model. Mass limits on bileptons are discussed
coming from $e^+e^-$ scattering, polarized muon decay and muonium-antimuonium
conversion. Discovery in $e^-e^-$ at a linear collider at low energy (100GeV)
and high luminosity ($10^{33}/cm^2/s$) is emphasised.}

</DOC>
<DOC>
<DOCNO> 68533 </DOCNO>
Does the quark-gluon plasma contain stable hadronic bubbles?


  We calculate the thermodynamic potential of bubbles of hadrons embedded in
quark-gluon plasma, and of droplets of quark-gluon plasma embedded in hadron
phase. This is a generalization of our previous results to the case of non-zero
chemical potentials. As in the zero chemical potential case, we find that a
quark-gluon plasma in thermodynamic equilibrium may contain stable bubbles of
hadrons of radius $R \simeq 1$ fm. The calculations are performed within the
MIT Bag model, using an improved multiple reflection expansion. The results are
of relevance for neutron star phenomenology and for ultrarelativistic heavy ion
collisions.

</DOC>
<DOC>
<DOCNO> 117052 </DOCNO>
Rotatable-Torsion-Balance Equivalence Principleexperiment for the


  We use a rotatable torsion balance to perform an equivalence principle test
on a magnetically shielded spin-polarized body of HoFe_{3}. With a rotation
period of one hour, the period of possible signal is reduced from one solar day
by 24 times, and hence the 1/f noise is greatly reduced. Our present
experimental results gives a limit (0.25 +- 1.26) X 10^{-9} on the Eotvos
parameter \eta of equivalence of the polarized body compared with unpolarized
aluminium-brass cylinders in the solar gravitional field, and a limit (0.34 +-
0.52) X 10^{-9} in the earth gravitional fields. This improves the previous
limit on polarized bodies by a factor of 45 for solar field and by a factor of
11 for earth field.

</DOC>
<DOC>
<DOCNO> 100688 </DOCNO>
Characteristic cycles and wave front cycles of representations of


  Vogan and Barbasch-Vogan attach two similar invariants to representations of
a reductive Lie group, one by an algebraic process, the other analytic. They
conjectured that the two invariants determine each other in a definite manner.
Here we prove the conjecture. Our arguments involve two finer invariants --
the characteristic cycles of representations -- which are interesting in their
own right.

</DOC>
<DOC>
<DOCNO> 70318 </DOCNO>
Generating QCD-antennas


  An extension of the SARGE-algorithm of \cite{HKD} is introduced, which
includes the incoming momenta in the kinematical pole structure of the density
with which the momenta are generated. The algorithm is compared with RAMBO in
the integration of QCD-amplitudes in the SPHEL-approximation, and the computing
times are extrapolated to those for the calculation with exact matrix elements.

</DOC>
<DOC>
<DOCNO> 121891 </DOCNO>
NLTE effects on oxygen lines


  The NLTE effects affecting oxygen-abundance determinations of solar-type
stars are discussed. LTE is perfectly safe for the forbidden lines. The
permitted triplet at 777 nm is expected to show NLTE effects on the order of a
few tenths of a dex (always in the sense that LTE overestimates the abundance),
but the magnitude of the effects is dependent on the still very uncertain cross
sections of collisional excitation by collisions with neutral hydrogen atoms.
Little is known about the NLTE effects on molecular line formation.

</DOC>
<DOC>
<DOCNO> 101771 </DOCNO>
Hopf quivers


  We classify graded Hopf algebras structures over path coalgebras, that is
over free pointed coalgebras, using Hopf quivers which are analogous to Cayley
graphs.
  The description involves formulas for the product besides the canonical
formulas for the coproduct. This makes explicit the quantum shuffle product
making use of natural elements in a Hopf bimodule having a simple "geometrical"
interpretation in the quiver sense, rather than working systematically with
right or left coinvariants.

</DOC>
<DOC>
<DOCNO> 170753 </DOCNO>
Relativistic quantum protocols: "Bit Commitment" and "Coin Tossing"


  The relativistic quantum protocols realizing the bit commitment and distant
coin tossing schemes are proposed. The protocols are based on the fact that the
non-stationary orthogonal extended quantum states cannot be reliably
distinguished if they are not fully accessible for the measurement. As the
states propagate from the domain controlled by one of the user to the domain
accessible for the measurements performed by the other user, they become
reliably distinguishable for the second user. Important for the protocol are
both the quantum nature of the states and the existence of a finite maximum
speed of the signal propagation imposed by the special relativity.

</DOC>
<DOC>
<DOCNO> 122657 </DOCNO>
Planet Detection Capabilities of the Eddington Mission


  Eddington is a space mission for extrasolar planet finding and for
asteroseismic observations. It has been selected by ESA as an F2/F3 reserve
mission with a potential implementation in 2008-13. Here we describe
Eddington's capabilities to detect extrasolar planets, with an emphasis on the
detection of habitable planets. Simulations covering the instrumental
capabilities of Eddington and the stellar distributions in potential target
fields lead to predictions of about 10,000 planets of all sizes and
temperatures, and a few tens of terrestrial planets that are potentially
habitable. Implications of Eddington for future larger scale missions are
briefly discussed.

</DOC>
<DOC>
<DOCNO> 170245 </DOCNO>
Coherent transport of matter waves


  A transport theory for atomic matter waves in low-dimensional waveguides is
outlined. The thermal fluctuation spectrum of magnetic near fields leaking out
of metallic microstructures is estimated. The corresponding scattering rate for
paramagnetic atoms turns out to be quite large in micrometer-sized waveguides
(approx. 100/s). Analytical estimates for the heating and decoherence of a cold
atom cloud are given. We finally discuss numerical and analytical results for
the scattering from static potential imperfections and the ensuing spatial
diffusion process.

</DOC>
<DOC>
<DOCNO> 122144 </DOCNO>
Fueling the AGN


  Active Galactic Nuclei are fueled from material (gas or stars) that are in
general far away from the gravitational influence of the central black hole,
the engine thought to be responsible for their activity. The required material
has a lot of angular momentum, that is a priori quite difficult to evacuate.
The various dynamical mechanisms that may play a role in this game are
reviewed, including m=2 perturbations (bars and spirals), m=1 perturbations
(spirals, warps, lopsidedness), and tidal interactions between galaxies and
mergers. In the latest stages of the merger, a binary black hole could be
formed, and its influence on the dynamics and fueling is discussed. Starbursts
are often associated with AGN, and the nature of their particular connection,
and their role in the nuclear fueling is described. Evolution of the fueling
efficiency with redshift is addressed.

</DOC>
<DOC>
<DOCNO> 69430 </DOCNO>
Asymptotic Behavior of Perturbations in Randall-Sundrum Brane-World


  The asymptotic behavior of metric perturbations in Randall-Sundrum infinite
brane world is carefully investigated. Perturbations generated by matter fields
on the brane are shown to be regular even at the future Cauchy horizon.

</DOC>
<DOC>
<DOCNO> 122206 </DOCNO>
Radio galaxies at z~2.5: results from Keck spectropolarimetry


  In classifying the ensemble of powerful extragalactic radio sources,
considerable evidence has accumulated that radio galaxies and quasars are
orientation-dependent manifestations of the same parent population: massive
spheroidal galaxies containing correspondingly massive black holes. [...] In
this study, we exploit the opportunity to eliminate the quasar glare by
performing sensitive spectropolarimetry with the Keck II telescope of a sample
of radio galaxies with redshifts around 2.5. [...] We show that dust-reflected
quasar light generally dominates the restframe ultraviolet continuum of these
sources and that a highly clumped scattering medium results in almost grey
scattering of the active galactic nucleus photons. The observations, however,
do not exclude a substantial star formation rate averaged over a Gyr of
evolution. The sub-mm reradiation from the scattering dust is likely to
represent only a small fraction (~10%) of the total far infrared luminosity. An
analysis of the emission lines excited in the interstellar medium of the host
galaxy by the hard quasar radiation field reveals evidence of a dramatic
chemical evolution within the spheroid during this epoch. Secondary nitrogen
production in intermediate mass stars produces a characteristic signature in
the NV/CIV and NV/HeII line ratios which has been seen previously in the broad
line region of quasars at similar redshifts. We find intriguing correlations
between the strengths of the Ly alpha and NV emission lines and the degree of
ultraviolet continuum polarization which may represent the dispersal of dust
associated with the chemical enrichment of the spheroid.

</DOC>
<DOC>
<DOCNO> 117999 </DOCNO>
Weak gravitational lensing in different cosmologies, using an algorithm


  We present the results of weak gravitational lensing statistics in four
different cosmological $N$-body simulations. The data has been generated using
an algorithm for the three-dimensional shear, which makes use of a variable
softening facility for the $N$-body particle masses, and enables a physical
interpretation for the large-scale structure to be made. Working in
three-dimensions also allows the correct use of the appropriate angular
diameter distances. Our results are presented on the basis of the filled beam
approximation in view of the variable particle softening scheme in our
algorithm. The importance of the smoothness of matter in the universe for the
weak lensing results is discussed in some detail. The low density cosmology
with a cosmological constant appears to give the broadest distributions for all
the statistics computed for sources at high redshifts. In particular, the range
in magnification values for this cosmology has implications for the
determination of the cosmological parameters from high-redshift Type Ia
Supernov\ae. The possibility of determining the density parameter from the
non-Gaussianity in the probability distribution for the convergence is
discussed.

</DOC>
<DOC>
<DOCNO> 118352 </DOCNO>
Use of DPOSS data to study globular cluster halos: an application to M


  We exploited the large areal coverage offered by the DPOSS to analyze the
outermost regions of the galactic globular cluster M 92. Two independent
photometric reduction programs (SKICAT and DAOPHOT) were used to construct a
color-magnitude diagram and a surface density profile for this cluster, based
on J- and F-band DPOSS plates. A strong similarity has been found in the
performance of the two programs in the low--crowded outermost cluster regions.
After removing the background contribution, we obtained the cluster outer
surface density profile down to a surface brightness magnitude of mu_V ~ 31
mag/sq.arcsec and matched it with the inner profile of Trager et al. 1995. The
profile shapes match very well: since our data are uncalibrated, the shift in
magnitude between the profiles has been also used to calibrate our profile. The
analysis shows that the cluster has an extra tidal halo extending out to ~ 30
arcmin from the cluster center at a 3 sigma level over the background noise.
This halo is revealed to be almost circular.

</DOC>
<DOC>
<DOCNO> 7877 </DOCNO>
Theory of Coherent $c$-Axis Josephson Tunneling between Layered


  We calculate exactly the Josephson current for $c$-axis coherent tunneling
between two layered superconductors, each with internal coherent tight-binding
intra- and interlayer quasiparticle dispersions. Our results also apply when
one or both of the superconductors is a bulk material, and include the usually
neglected effects of surface states. For weak tunneling, our results reduce to
our previous results derived using the tunneling Hamiltonian. Our results are
also correct for strong tunneling. However, the $c$-axis tunneling results of
Tanaka and Kashiwaya are shown to be incorrect in any limit. In addition, we
consider the $c$-axis coherent critical current between two identical layered
superconductors twisted an angle $\phi_0$ about the $c$-axis with respect to
each other. Regardless of the order parameter symmetry, our coherent tunneling
results using a tight-binding intralayer quasiparticle dispersion are
inconsistent with the recent $c$-axis twist bicrystal
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ twist junction experiments of Li {\it et
al.}

</DOC>
<DOC>
<DOCNO> 71358 </DOCNO>
Rho meson properties in nuclear matter from QCD sum rules


  We study the properties of rho mesons in nuclear matter by means of QCD sum
rules at finite density. For increased sensitivity, we subtract out the vacuum
contributions. With the spectral function as estimated in the literature, these
subtracted sum rules are found to be not well satisfied. We suppose that Landau
singularities from higher resonance states in the nearby region in this channel
are the cause for this failure.

</DOC>
<DOC>
<DOCNO> 121829 </DOCNO>
Planets and Axisymmetric Mass Loss


  Bipolar planetary nebulae (PNe), as well as extreme elliptical PNe are formed
through the influence of a stellar companion. But half of all PN progenitors
are not influenced by any stellar companion, and, as I show here, are expected
to rotate very slowly on reaching the upper asymptotic giant branch; hence they
expect to form spherical PNe, unless they are spun-up. But since most PNe are
not spherical, I argue that about 50 percents of AGB stars are spun-up by
planets, even planets having a mass as low as 0.01 times the mass of Jupiter,
so they form elliptical PNe. The rotation by itself will not deform the AGB
wind, but may trigger another process that will lead to axisymmetric mass loss,
e.g., weak magnetic activity, as in the cool magnetic spots model. This model
also explains the transition from spherical to axisymmetric mass loss on the
upper AGB. For such low mass planets to substantially spin-up the stellar
envelope, they should enter the envelope when the star reaches the upper AGB.
This "fine-tuning" can be avoided if there are several planets on average
around each star, as is the case in the solar system, so that one of them is
engulfed when the star reaches the upper AGB.

</DOC>
<DOC>
<DOCNO> 119821 </DOCNO>
Quasar environments at 0.5 < z < 0.8


  Over the past few years, we have been collecting data with the Nordic Optical
Telescope (NOT) on the galaxy environments around active galactic nuclei (AGN).
Here we present some results from a sample of 21 radio-loud and 20 radio-quiet
quasars in the redshift range 0.5 < z < 0.8. We find a few quasars in very rich
environments, perhaps as rich as Abell class 1-2 clusters, but more often the
quasars seem to prefer groups and poorer clusters. We also find that on average
the galaxy environments around radio-loud and radio-quiet quasars are
indistinguishable, consistent with the findings that both powerful radio-loud
and radio-quiet quasars appear to be hosted by luminous galaxies with
luminosities higher than the break in the luminosity function (Dunlop et al.
1993; Taylor et al. 1996). Comparing the galaxy richnesses in the radio-loud
quasar fields with quasar fields in the literature, we find a weak, but
significant, correlation between quasar radio luminosity and environmental
richness.

</DOC>
<DOC>
<DOCNO> 9000 </DOCNO>
Critical light scattering in liquids


  We compare theoretical results for the characteristic frequency of the
Rayleigh peak calculated in one-loop order within the field theoretical method
of the renormalization group theory with experiments and other theoretical
results. Our expressions describe the non-asymptotic crossover in temperature,
density and wave vector. In addition we discuss the frequency dependent shear
viscosity evaluated within the same model and compare our theoretical results
with recent experiments in microgravity.

</DOC>
<DOC>
<DOCNO> 9189 </DOCNO>
Correlations due to localization in quantum eigenfunctions of disordered


  Non-universal correlations due to localization are observed in statistical
properties of experimental eigenfunctions of quantum chaotic and disordered
microwave cavities. Varying energy {E} and mean free path {l} enable us to
experimentally tune from localized to delocalized states. Large level-to-level
Inverse Participation Ratio (IPR I_{2}) fluctuations are observed for the
disordered billiards, whose distribution is strongly asymmetric about <I_{2}>.
The density auto-correlations of eigenfunctions are shown to decay
exponentially and the decay lengths are experimentally determined. All the
results are quantitatively consistent with calculations based upon nonlinear
sigma-models.

</DOC>
<DOC>
<DOCNO> 152295 </DOCNO>
Orbifold boundary states from Cardy's condition


  Boundary states for D-branes at orbifold fixed points are constructed in
close analogy with Cardy's derivation of consistent boundary states in RCFT.
Comments are made on the interpretation of the various coefficients in the
explicit expressions, and the relation between fractional branes and wrapped
branes is investigated for $\mathbb{C}^2/\Gamma$ orbifolds. The boundary states
are generalised to theories with discrete torsion and a new check is performed
on the relation between discrete torsion phases and projective representations.

</DOC>
<DOC>
<DOCNO> 102370 </DOCNO>
Path integral quantization of Yang-Mills theory


  Path integral formulation based on the canonical method is discussed. Path
integral for Yang-Mills theory is obtained by this procedure. It is shown that
gauge fixing which is essential procedure to quantize singular systems by
Faddeev's and Popov's method is not necessary if the canonical path integral
formulation is used.

</DOC>
<DOC>
<DOCNO> 12756 </DOCNO>
Entropy fluctuations for directed polymers in 2+1 dimensions


  We find numerically that the sample to sample fluctuation of the entropy,
$\Delta S$, is a tool more sensitive in distinguishing how from high
temperature behaviors, than the corresponding fluctuation in the free energy.
In 1+1 dimensions we find a single phase for all temperatures since $(\Delta
S)^{2}$ is always extensive. In 2+1 dimensions we find a behavior may look at
first sight as a transition from a low temperature phase where $(\Delta S)^{2}$
is extensive to a high temperature phase where it is subextensive. This is
observed in spite of the relatively large system we use. The observed behavior
is explained not as a phase transition but as a strong crossover behavior. We
use an analytical agreement to obtain $(\Delta S)^{2}$ for high temperature and
find that while it is always extensive it is also extremly small and the
leading extensive part decays very fast to zero as temperature is increased.

</DOC>
<DOC>
<DOCNO> 121056 </DOCNO>
Corrections to the Predicitions for Atmospheric Neutrino Observations


  The theoretical Monte Carlo calculations of the production of neutrinos via
cosmic rays incident upon the earth's atmosphere are examined. The calculations
are sensitive to the assumed ratio of pi+ / pi- production cross sections; this
ratio appears to be underestimated in the theory relative to the experimentally
measured ratio. Since the neutrino detection cross section is three times
larger than that for the antineutrino, the theoretical predicted detection
ratio (nu_mu / nu_e) is correspondingly too large.

</DOC>
<DOC>
<DOCNO> 120056 </DOCNO>
The Absolute Proper Motion of Palomar 12: A Case for Tidal Capture from


  We have measured the absolute proper motion of the young globular cluster Pal
12 with respect to background galaxies, using plate material spanning a 40-year
time baseline, and measuring stars down to a magnitude V~22. The measured
absolute proper motion has an uncertainty of 0.3 mas/yr in each coordinate.
  Pal 12's young age for a globular cluster led to the hypothesis that the
cluster originated in the Large Magellanic Cloud (LMC) and was later captured
by the Milky Way (Lin and Richer 1992). Here we investigate this hypothesis
using the complete kinematical data. We present the orbital characteristics of
Pal 12 and compare them with those of the LMC and Sagittarius dwarf galaxy
(Sgr). The present kinematical data suggest that, from the two parent
candidates for Pal 12, Sgr presents a more plausible case for the host galaxy
than the LMC.
  We explore this scenario in the context of the uncertainties in the orbits
and using two different analyses: the direct comparison of the orbits of Pal 12
and Sgr as a function of time, and the analytical model of Sgr's tidal
disruption developed by Johnson (1998). We find that, within the present
uncertainties of the observables, this scenario is viable in both methods.
Moreover, both methods place this event at the same point in time. Our best
estimate of the time of Pal 12's tidal capture from Sgr is ~ 1.7 Gyr ago.

</DOC>
<DOC>
<DOCNO> 85263 </DOCNO>
Mass dependence of the gravitationally-induced wave-function phase


  The leading mass dependence of the wave function phase is calculated in the
presence of gravitational interactions. The conditions under which this phase
contains terms depending on both the square of the mass and the gravitational
constant are determined. The observability of such terms is briefly discussed.

</DOC>
<DOC>
<DOCNO> 101394 </DOCNO>
K-theory of C^*-algebras from one-dimensional generalized solenoids


  We compute the K-groups of C^*-algebras arising from one-dimensional
generalized solenoids. The results show that Ruelle algebras from
one-dimensional generalized solenoids are one-dimensional generalizations of
Cuntz-Krieger algebras.

</DOC>
<DOC>
<DOCNO> 151151 </DOCNO>
Path-Integral Measures in Higher-Derivative Gravities


  A simple method of obtaining path-integral measures in higher-derivative
gravities is presented. The measures are nothing but the generalized Lee-Yang
terms.

</DOC>
<DOC>
<DOCNO> 12494 </DOCNO>
Phase diagrams of polydisperse van der Waals fluids


  The phase behavior of a system composed of spherical particles with a
monomodal size distribution is investigated theoretically within the context of
the van der Waals approximation for polydisperse fluids. It is shown how the
binodals, spinodals, cloud-point and shadow curves as well as all the
(polydispersity induced) critical points can be obtained for a variety of
interaction potentials. The polydispersity induced modifications of the phase
diagram (even for a polydispersity index $I$ as small as $I\approx 1.01$)
should be observable in some colloidal dispersions.

</DOC>
<DOC>
<DOCNO> 170718 </DOCNO>
Atom Optics with Microfabricated Optical Elements


  We introduce a new direction in the field of atom optics, atom
interferometry, and neutral-atom quantum information processing. It is based on
the use of microfabricated optical elements. With these elements versatile and
integrated atom optical devices can be created in a compact fashion. This
approach opens the possibility to scale, parallelize, and miniaturize atom
optics for new investigations in fundamental research and application. It will
lead to new, compact sources of ultracold atoms, compact sensors based on
matter wave interference and new approaches towards quantum computing with
neutral atoms. The exploitation of the unique features of the quantum
mechanical behavior of matter waves and the capabilities of powerful
state-of-the-art micro- and nanofabrication techniques lend this approach a
special attraction.

</DOC>
<DOC>
<DOCNO> 83147 </DOCNO>
Security of the Cao-Li Public Key Cryptosystem


  We show that the Cao-Li cryptosystem proposed in \cite{CL1} is not secure.
Its private key can be reconstructed from its public key using elementary means
such as LU-decomposition and Euclidean algorithm.

</DOC>
<DOC>
<DOCNO> 40119 </DOCNO>
Evidence of New States Decaying into Xi_c^{prime} pi


  Using 13.7 fb^{-1} of data recorded by the CLEO detector at CESR, we report
preliminary evidence for two new charmed baryons; one decaying into
Xi_c^{0\prime} pi^+ with the subsequent decay Xi_c^{0\prime} to Xi_c^0 gamma,
and its isospin partner decaying into Xi_c^{+\prime} pi^- followed by
Xi_c^{+\prime} to Xi_c^+ gamma. We measure the following mass differences for
the two states: M(Xi_c^0 gamma pi^+)-M(\Xi_c^0)=318.4+-1.5+-2.9 MeV, and
M(Xi_c^+ gamma pi^-)-M(Xi_c^+)=323.9+-pm1.4+-pm3.0 MeV. We interpret these new
states as the J^P = (1/2)^-1 Xi_{c1} particles, the charmed-strange analogues
of the Lambda_{c1}^+(2593).

</DOC>
<DOC>
<DOCNO> 69819 </DOCNO>
NN Scattering Phase Shifts in a Chiral Constituent Quark Model


  We study the nucleon-nucleon interaction within a chiral constituent quark
model which reproduces succesfully the baryon spectra. We calculate the 3S1 and
1S0 phase shifts by using the resonating group method. They clearly indicate
the presence of a strong repulsive interaction at short distance, due to the
spin-flavor symmetry of the quark-quark interaction and of the quark
interchange between the two interacting nucleons. A sigma-exchange quark-quark
interaction, providing a medium-range attraction, helps to get closer to the
experimental phase shifts.

</DOC>
<DOC>
<DOCNO> 68390 </DOCNO>
Analysis of atmospheric neutrino oscillations in three-flavor neutrinos


  We analyze the atmospheric neutrino experiments of Super-Kamiokande (830-920
live days) using the three-flavor neutrino framework with the mass hierarchy
m_1 nearly equal m_2 << m_3. We study the sub-GeV, multi- GeV neutrinos and
upward through-going and stopping muons zenith angle distributions taking
account of the Earth matter effects thoroughly. We obtain the allowed regions
of mass and mixing parameters Delm^2_{23}, theta_{13} and theta_{23}.
Delm^2_{23} is restricted to 0.002-0.01eV^2 and theta_{13}<13degrees,
35degrees<theta_{23}<55degrees in 90% C.L. For theta_{12}, there is no
difference between the large angle solar neutrino solution and small one. From
chi^2 fit, the minimum chi^2=55(54DOF) is obtained at
Delm^2_{23}=4x10^(-3)eV^2, theta_{13}=10degrees and theta_{23} =45degrees.

</DOC>
<DOC>
<DOCNO> 151852 </DOCNO>
Tachyon instability and Kondo type models


  In this paper we investigate the tachyon instability of open bosonic string
theory applying methods of boundary conformal field theory. We consider
compactifications on maximal tori of various simple Lie algebras with a
specific background coupled to the string boundaries. The resulting world-sheet
CFT is a free theory perturbed by a boundary term that is marginal but not
truly marginal. Assuming that the theory flows to a nontrivial infrared fixed
point that is similar to the one in Kondo model, we calculate the new spectrum
and some of the Green's functions. We find that in some of the sectors the
tachyon mass gets lifted that can be interpreted as a result of switching on
appropriate Wilson lines. Various compactifications and patterns of flows are
investigated.

</DOC>
<DOC>
<DOCNO> 85004 </DOCNO>
Fractal Statistics and Quantum Black Hole Entropy


  Simple considerations about the fractal characteristic of the
quantum-mechanical path give us the opportunity to derive the quantum black
hole entropy in connection with the concept of fractal statistics. We show the
geometrical origin of the numerical factor of four of the quantum black hole
entropy expression and the statistics weight appears as a counting of the
quanta of geometry.

</DOC>
<DOC>
<DOCNO> 151456 </DOCNO>
N=2 Quantum String Scattering


  We calculate the genus-one three- and four-point amplitudes in the 2+2
dimensional closed N=(2,2) worldsheet supersymmetric string within the RNS
formulation. Vertex operators are redefined with the incorporation of spinor
helicity techniques, and the quantum scattering is shown to be manifestly gauge
and Lorentz invariant after normalizing the string states. The continuous spin
structure summation over the monodromies of the worldsheet fermions is carried
out explicitly, and the field-theory limit is extracted. The amplitude in this
limit is shown to be the maximally helicity violating amplitude in pure gravity
evaluated in a two-dimensional setting, which vanishes, unlike the
four-dimensional result. The vanishing of the genus-one N=2 closed string
amplitude is related to the absence of one-loop divergences in dimensionally
regulated IIB supergravity. Comparisons and contrasts between self-dual field
theory and the N=2 string theory are made at the quantum level; they have
different S-matrices. Finally, we point to further relations with self-dual
field theory and two-dimensional models.

</DOC>
<DOC>
<DOCNO> 118985 </DOCNO>
The Sun, stellar-population models, and the age estimation of


  Given sufficiently deep optical spectroscopy, the age estimation of
high-redshif t ($z > 1$) galaxies has been claimed to be a relatively robust
process (e.g. Dunlop et al. 1996) due to the fact that, for ages $< 5$Gyr, the
near-ultraviolet light of a stellar population is expected to be dominated by
`well-understood' main-sequence (MS) stars. Recently, however, the reliability
of this process has been called into question by Yi et al (2000), who claim to
have developed models in which the spectrum produced by the main sequence
reddens much more rapidly than in the models of Jimenez et al (2000a), leading
to much younger age estimates for the reddest known high-redshift ellipticals.
In support of their revised age estimates, Yi et al cite the fact that their
models can reproduce the spectrum of the Sun at an age of 5 Gyr, whereas the
solar spectrum is not reproduced by the Jimenez et al models until $\simeq 10$
Gyr. Here we confirm this discrepancy, but point out that this is in fact a
{\it strength} of the Jimenez et al models and indicative of some flaw in the
models of Yi et al (which, in effect, imply that the Sun will turn into a red
giant any minute now). We have also explored the models of Worthey (1994)
(which are known to differ greatly from those of Jimenez et al in the treatment
of post-MS evolution) and find that the main-sequence component of Worthey's
models also cannot reproduce the solar spectrum until an age of 9-10 Gyr. We
conclude that either the models of Yi et al are not as main-sequence dominated
at 4-5 Gyr as claimed, or that the stellar evolutionary timescale in these
models is in error by a factor possibly as high as two. (abridged)

</DOC>
<DOC>
<DOCNO> 99723 </DOCNO>
Degenerate affine Hecke algebras and centralizer construction for the


  In our recent papers the centralizer construction was applied to the series
of classical Lie algebras to produce the quantum algebras called (twisted)
Yangians. Here we extend this construction to the series of the symmetric
groups S(n). We study the `stable' properties of the centralizers of S(n-m) in
the group algebra C[S(n)] as n increases with m fixed. We construct a limit
centralizer algebra A and describe its algebraic structure. The algebra A turns
out to be closely related with the degenerate affine Hecke algebras. We also
show that the so-called tame representations of the infinite symmetric group
yield a class of natural A-modules.

</DOC>
<DOC>
<DOCNO> 7695 </DOCNO>
Connection between charge transfer and alloying core-level shifts based


  The measurement of alloying core-level binding energy (CLBE) shifts has been
used to give a precise meaning to the fundamental concept of charge transfer.
Here, ab-initio density-functional calculations for the intermetallic compound
MgAu are used to investigate models which try to make a connection between the
core levels shifts and charge transfer. The calculated CLBE shifts agree well
with experiment, and permit an unambiguous separation into initial-state and
screening contributions. Interestingly, the screening contribution is large and
cannot be neglected in any reasonable description. Comparison of the calculated
results with the predictions of simple models show that these models are not
adequate to describe the realistic situation. On the positive side, the
accuracy of the density-functional calculations indicates that the combination
of experiments with such calculations is a powerful tool to investigate unknown
systems.

</DOC>
<DOC>
<DOCNO> 101865 </DOCNO>
Introduction to Symplectic Field Theory


  We sketch in this article a new theory, which we call Symplectic Field Theory
or SFT, which provides an approach to Gromov-Witten invariants of symplectic
manifolds and their Lagrangian submanifolds in the spirit of topological field
theory, and at the same time serves as a rich source of new invariants of
contact manifolds and their Legendrian submanifolds. Moreover, we hope that the
applications of SFT go far beyond this framework.

</DOC>
<DOC>
<DOCNO> 70582 </DOCNO>
The Light-Cone Wave Function of the Pion


  The light-cone wave function of the pion is calculated within the
Nambu-Jona-Lasinio model. The result is used to derive the pion electromagnetic
form factor, charge radius, structure function, pi-gamma transition form factor
and distribution amplitude.

</DOC>
<DOC>
<DOCNO> 68710 </DOCNO>
Penguin Enhancement and $B\to K\pi$ decays in perturbative QCD


  We compute branching ratios of $B\to K\pi$ decays in the framework of
perturbative QCD factorization theorem. Decay amplitudes are classified into
the topologies of tree, penguin and annihilation, all of which contain both
factorizable and nonfactorizable contributions. These contributions are
expressed as the convolutions of hard $b$ quark decay amplitudes with universal
meson wave functions. It is shown that (1) matrix elements of penguin operators
are dynamically enhanced compared to those employed in the factorization
assumption; (2) annihilation diagrams are not negligible, contrary to common
belief; (3) annihilation diagrams contribute large strong phases; (4) the
uncertainty of current data of the ratio $R={\cal B}(B_d^0\to
K^\pm\pi^\mp)/{\cal B}(B^\pm\to K^0\pi^\pm)$ and of CP asymmetries is too large
to give a constraint of $\phi_3$. Assuming $\phi_3=90^o$ which is extracted
from the best fit to the data of $R$, predictions for the branching ratios of
the four $B\to K\pi$ modes are consistent with data.

</DOC>
<DOC>
<DOCNO> 102570 </DOCNO>
Clifford Hopf gebra for two-dimensional space


  A Clifford algebra Cl(V,\eta\in V^*\otimes V^*) jointly with a Clifford
cogebra Cl(V,\xi\in V\otimes V) is said to be a Clifford biconvolution
Cl(\eta,\xi). We show that a Clifford biconvolution for dim_R Cl=4 does possess
an antipode iff det(id-\xi\circ\eta)\neq 0. An antipodal Clifford biconvolution
is said to be a Clifford Hopf gebra. We study the Clifford Hopf gebra and
examples of antipode less Clifford bigebras including the Grassmann case.

</DOC>
<DOC>
<DOCNO> 116252 </DOCNO>
Large-scale Breit-Pauli R-matrix calculations for transition


  Ab initio theoretical calculations are reported for the electric (E1) dipole
allowed and intercombination fine structure transitions in Fe V using the
Breit-Pauli R-matrix (BPRM) method. We obtain 3865 bound fine structure levels
of Fe V and $1.46 x 10^6$ oscillator strengths, Einstein A-coefficients and
line strengths. In addition to the relativistic effects, the intermediate
coupling calculations include extensive electron correlation effects that
represent the complex configuration interaction (CI). Fe V bound levels are
obtained with angular and spin symmetries $SL\pi$ and $J\pi$ of the (e + Fe VI)
system such that $2S+1$ = 5,3,1, $L \leq$ 10, $J \leq 8$. The bound levels are
obtained as solutions of the Breit-Pauli (e + ion) Hamiltonian for each $J\pi$,
and are designated according to the `collision' channel quantum numbers. A
major task has been the identification of these large number of bound fine
structure levels in terms of standard spectroscopic designations. A new scheme,
based on the analysis of quantum defects and channel wavefunctions, has been
developed. The identification scheme aims particularly to determine the
completeness of the results in terms of all possible bound levels for
applications to analysis of experimental measurements and plasma modeling. An
uncertainty of 10-20% for most transitions is estimated.

</DOC>
<DOC>
<DOCNO> 9027 </DOCNO>
A dynamical model describing stock market price distributions


  High frequency data in finance have led to a deeper understanding on
probability distributions of market prices. Several facts seem to be well
stablished by empirical evidence. Specifically, probability distributions have
the following properties: (i) They are not Gaussian and their center is well
adjusted by Levy distributions. (ii) They are long-tailed but have finite
moments of any order. (iii) They are self-similar on many time scales. Finally,
(iv) at small time scales, price volatility follows a non-diffusive behavior.
We extend Merton's ideas on speculative price formation and present a dynamical
model resulting in a characteristic function that explains in a natural way all
of the above features. The knowledge of such distribution opens a new and
useful way of quantifying financial risk. The results of the model agree -with
high degree of accuracy- with empirical data taken from historical records of
the Standard & Poor's 500 cash index.

</DOC>
<DOC>
<DOCNO> 12878 </DOCNO>
Magnetic Phase Transitions in the double spin-chains compound $\rm


  We report high-resolution x-ray diffraction, muon-spin-rotation spectroscopic
and specific heat measurements in the double spin-chains compound $\rm
LiCu_2O_2$. The x-ray diffraction results show that the crystal structure of
$\rm LiCu_2O_2$ ~is orthorhombic down to T=10K. Anisotropic line-broadening of
the diffraction peaks is observed, indicating disorder along the spin chains.
Muon spin relaxation and specific heat measurements show that $\rm LiCu_2O_2$
\~undergoes a phase transition to a magnetic ordered state at $\rm T_1\sim24K$.
The specific heat data exhibits a second $\rm \lambda$-like peak at $\rm
T_2\sim22.5 K$, which increases with increasing magnetic field similarly way to
that found in spin-ladder compounds.

</DOC>
<DOC>
<DOCNO> 13135 </DOCNO>
The Superfluid Density in the D-density-wave Scenario


  Recently Chakravarty, Laughlin, Morr and Nayak made an interesting proposal
that the cuprate superconductors possess a hidden ``d-density wave'' order. We
study the implication of this proposal for the superfluid density \rho_s. We
find that it predicts a temperature gradient |d\rho_s/dT|_{T=0} that is
strongly doping dependent near the critical doping (\approx 5%) at which the
superconducting transition temperature vanishes.

</DOC>
<DOC>
<DOCNO> 9464 </DOCNO>
Stripes ordering in self-stratification experiments of binary and


  The self-stratification of binary and ternary granular mixtures has been
experimentally investigated. Ternary mixtures lead to a particular ordering of
the strates which was not accounted for in former explanations. Bouncing grains
are found to have an important effect on strate formation. A complementary
mechanism for self-stratification of binary and ternary granular mixtures is
proposed.

</DOC>
<DOC>
<DOCNO> 101319 </DOCNO>
On the Jones polynomials of checkerboard colorable virtual knots


  The notion of chckerboard colorability for virtual links and abstract links
is introduced. We study the Jones polynomials of virtual links and abstruct
links. It is proved that a certain property of the Jones polynomials of
classical links is valid for virtual links which admit checkerboard colorings.

</DOC>
<DOC>
<DOCNO> 99636 </DOCNO>
On bifurcations from normal solutions for superconducting states


  Motivated by the paper by J. Berger and K. Rubinstein \cite{BeRu} and other
recent studies \cite{GiPh}, \cite{LuPa1}, \cite{LuPa2}, we analyze the
Ginzburg-Landau functional in an open bounded set $\Omega$. We mainly discuss
the bifurcation problem whose analysis was initiated in \cite{Od} and show how
some of the techniques developed by the first author in the case of Abrikosov's
superconductors \cite{Du} can be applied in this context. In the case of non
simply connected domains, we come back to \cite{BeRu} and \cite{HHOO},
\cite{HHOO1} for giving the analysis of the structure of the nodal sets for the
bifurcating solutions.

</DOC>
<DOC>
<DOCNO> 7802 </DOCNO>
Time Dependent Current Oscillations Through a Quantum Dot


  Time dependent phenomena associated to charge transport along a quantum dot
in the charge quantization regime is studied. Superimposed to the Coulomb
blockade behaviour the current has novel non-linear properties. Together with
static multistabilities in the negative resistance region of the I-V
characteristic curve, strong correlations at the dot give rise to
self-sustained current and charge oscillations. Their properties depend upon
the parameters of the quantum dot and the external applied voltages.

</DOC>
<DOC>
<DOCNO> 12819 </DOCNO>
Nuclear Magnetic Relaxation in Sc Metal


  The nuclear magnetic relaxation in scandium metal is investigated at liquid
helium temeprature for both single crystal and powder samples. The obtained
temperature and field dependence of the Korringa constant are described by the
means of the spin uctuation theory. It is shown that one of the reason for the
high field decreasing of the relaxation rate is the quenching of spin
uctuations. The other possible reason is the magnetic impurity influence. The
reasons of the existing variations of the Korringa constant are discussed. The
possible sources of non-single exponential relaxation are investigated.

</DOC>
<DOC>
<DOCNO> 170407 </DOCNO>
Two-particle model with noncommuting operators of coordinates and


  A nonrelativistic equation for the system of two interacting particles within
the framework of a model with noncommuting operators of coordinates and momenta
of different particles is proposed, and a self-consistent system of equations
for the wave function of every quantum state is deduced. Solutions for the
lowest states of a hydrogenlike atom are found, and the comparison with
analogous solutions of the Klein-Gordon equation for the relativistic spinless
problem is performed. In the case where the size of a two-particle system and
the Compton wavelengths of particles forming it are of the same order, the
essential differences with solutions of the Schr\"{o}dinger nonrelativistic
equation are revealed.

</DOC>
<DOC>
<DOCNO> 170095 </DOCNO>
Adiabatic approximation from a renormalization group inspired method


  We show how a method inspired in renormalization group techniques can be
useful for deriving Hamiltonians in the adiabatic approximation in a systematic
way.

</DOC>
<DOC>
<DOCNO> 169657 </DOCNO>
Antiparticle in Light of Einstein-Podolsky-Rosen Paradox and Klein


  The original version of Einstein-Podolsky-Rosen (EPR) paradox and the Klein
paradox of Klein-Gordon (KG) equation are discussed to show the necessity of
existence of antiparticle with its wavefunction being fixed unambiguously. No
concept of "hole" is needed.

</DOC>
<DOC>
<DOCNO> 116890 </DOCNO>
Bridge Coupler for APT


  The Coupled Cavity Drift Tube Linac (CCDTL) used in the Accelerator for the
Production of Tritium (APT) is fully described elsewhere [1]. The modules are
composed of several machined and brazed segments that must account for the
accumulation of dimensional tolerances in the build up of the stack. In
addition, space requirements dictate that power fed to the accelerator cannot
be through the accelerating cavities. As well, we would like to remove a single
segment of the accelerator without removing additional segments. These
requirements combined with phasing relationships of the design and space
limitations have resulted in a different bridge coupling method used in the
module comprising 3-gap segments. The coupling method, phasing relationships
and other features that enhance the flexibility of the design will be
discussed.

</DOC>
<DOC>
<DOCNO> 10308 </DOCNO>
Andreev Peaks and Massive Magnons in Cuprate SNS junctions


  The projected SO(5) theory (pSO(5)) is used to resolve the puzzle of two
distinct energy gaps in high T$_c$ Superconductor-Normal-Superconductor
junctions. Counter to conventional theory of multiple Andreev reflections
(MAR), the differential resistance peaks are associated with the
antiferromagnetic resonance observed in neutron scattering, and not with Cooper
pair breaking. The pSO(5) and MAR theories differ by the expected tunneling
charges at the peaks. We propose that shot noise experiments could discriminate
against the conventional interpretation.

</DOC>
<DOC>
<DOCNO> 84510 </DOCNO>
Can the Universe escape eternal acceleration?


  Recent astronomical observations of distant supernovae light-curves suggest
that the expansion of the universe has recently begun to accelerate.
Acceleration is created by an anti-gravitational repulsive stress, like that
produced by a positive cosmological constant, or universal vacuum energy. It
creates a rather bleak eschatological picture. An ever-expanding universe's
future appears to be increasingly dominated by its constant vacuum energy. A
universe doomed to accelerate forever will produce a state of growing
uniformity and cosmic loneliness. Structures participating in the cosmological
expansion will ultimately leave each others' horizons and
information-processing must eventually die out. Here, we examine whether this
picture is the only interpretation of the observations. We find that in many
well-motivated scenarios the observed spell of vacuum domination is only a
transient phenomenon. Soon after acceleration starts, the vacuum energy's
anti-gravitational properties are reversed, and a matter-dominated decelerating
cosmic expansion resumes. Thus, contrary to general expectations, once an
accelerating universe does not mean always an accelerating universe.

</DOC>
<DOC>
<DOCNO> 118049 </DOCNO>
Present and Near-Future Reflected Light Searches for Close-In Planets


  Close-in extrasolar giant planets may be directly detectable by their
reflected light, due to the proximity of the planet to the illuminating star.
The spectrum of the system will contain a reflected light component that varies
in amplitude and Doppler shift as the planet orbits the star. Intensive
searches for this effect have been carried out for only one extrasolar planet
system, tau Boo. There exist several other attractive targets, including the
transiting planet system HD 209458.

</DOC>
<DOC>
<DOCNO> 121727 </DOCNO>
Diffraction Limited Imaging of High Redshift Galaxies with Adaptive


  The major cornerstone of future ground-based astronomy is imaging and
spectroscopy at the diffraction limit using adaptive optics. To exploit the
potential of current AO systems, we have begun a survey around bright stars to
study intermediate redshift galaxies at high resolution. Using ALFA to reach
the diffraction limit of the 3.5-m telescope at Calar Alto allows us to study
the structure of distant galaxies in the near-infrared at scales of 100-150 pc
for z=0.05 and at scales 1.0-1.5 kpc at z=1. In this contribution we present
the initial results of this project, which hint at the exciting prospects
possible with the resolution and sensitivity available using an AO camera on
the 8-m class VLT.

</DOC>
<DOC>
<DOCNO> 118952 </DOCNO>
Nonlinear stochastic biasing from the formation epoch distribution of


  We propose a physical model for nonlinear stochastic biasing of one-point
statistics resulting from the formation epoch distribution of dark halos. In
contrast to previous works on the basis of extensive numerical simulations, our
model provides for the first time an analytic expression for the joint
probability function. Specifically we derive the joint probability function of
halo and mass density contrasts from the extended Press-Schechter theory. Since
this function is derived in the framework of the standard gravitational
instability theory assuming the random-Gaussianity of the primordial density
field alone, we expect that the basic features of the nonlinear and stochastic
biasing predicted from our model are fairly generic. As representative
examples, we compute the various biasing parameters in cold dark matter models
as a function of a redshift and a smoothing length. Our major findings are (1)
the biasing of the variance evolves strongly as redshift while its
scale-dependence is generally weak and a simple linear biasing model provides a
reasonable approximation roughly at $R\simgt 2(1+z)\himpc$, and (2) the
stochasticity exhibits moderate scale-dependence especially on $R\simlt
20\himpc$, but is almost independent of $z$. Comparison with the previous
numerical simulations shows good agreement with the above behavior, indicating
that the nonlinear and stochastic nature of the halo biasing is essentially
understood by taking account of the distribution of the halo mass and the
formation epoch.

</DOC>
<DOC>
<DOCNO> 8015 </DOCNO>
s+d pairing in orthorhombic phase of copper-oxides


  A microscopical theory of electronic spectrum and superconductivity is
formulated within the two-dimensional anisotropic t-J model with t_{x}\neq
t_{y} and J_{x}\neq J_{y}. Renormalization of electronic spectrum and
superconductivity mediated by spin-fluctuations are investigated within the
Eliashberg equation in the weak coupling approximation. The gap function has
d+s symmetry with the extended s-wave component being proportional to the
asymmetry t_{y} - t_{x}. Some experimental consequences of the obtained results
are discussed.

</DOC>
<DOC>
<DOCNO> 169982 </DOCNO>
Minimal irreversible quantum mechanics. The decay of unstable states


  Brownian motion is modelled by a harmonic oscillator (Brownian particle)
interacting with a continuous set of uncoupled harmonic oscillators. The
interaction is linear in the coordinates and the momenta. The model has an
analytical solution that is used to study the time evolution of the reduced
density operator. It is derived in a closed form, in the one-particle sector of
the model. The irreversible behavior of the Brownian particle is described by a
reduced density matrix.

</DOC>
<DOC>
<DOCNO> 152159 </DOCNO>
On Exact Noncommutative BPS Solitons


  We construct new exact BPS solitons in various noncommutative gauge theories
by the ``gauge'' transformation of known BPS solitons. This ``gauge''
transformation introduced by Harvey, Kraus and Larsen adds localized solitons
to the known soliton. These solitons include, for example, the bound state of a
noncommutative Abelian monopole and N fluxons at threshold. This corresponds,
in superstring theories, to a D-string which attaches to a D3-brane and N
D-strings which pierce the D3-brane, where all D-strings are parallel to each
other.

</DOC>
<DOC>
<DOCNO> 85159 </DOCNO>
Nonlinear Connections and Nearly Autoparallel Maps in General Relativity


  We apply the method of moving anholonomic frames, with associated nonlinear
connections, in (pseudo) Riemannian spaces and examine the conditions when
various types of locally anisotropic (la) structures (Lagrange, Finsler like
and more general ones) could be modeled in general relativity. New classes of
solutions of the Einstein equations with generic local anisotropy are
constructed. We formulate the theory of nearly autoparallel (na) maps and
introduce the tensorial na-integration as the inverse operation to both
covariant derivation and deformation of connections by na-maps. The problem of
redefinition of the Einstein gravity theory on na-backgrounds, provided with a
set of na-map invariant conditions and local conservation laws, is analyzed.
There are illustrated some examples of generation of vacuum Einstein fields by
Finsler like metrics and chains of na-maps.

</DOC>
<DOC>
<DOCNO> 101275 </DOCNO>
Filling Length in Finitely Presentable Groups


  Filling length measures the length of the contracting closed loops in a
null-homotopy. The filling length function of Gromov for a finitely presented
group measures the filling length as a function of length of edge-loops in the
Cayley 2-complex. We give a bound on the filling length function in terms of
the log of an isoperimetric function multiplied by a (simultaneously
realisable) isodiametric function.

</DOC>
<DOC>
<DOCNO> 14004 </DOCNO>
Model study for the nonequlibrium magnetic domain structure during the


  The nonequilibrium magnetic domain structure of growing ultrathin
ferromagnetic films with a realistic atomic structure is studied as a function
of coverage and temperature. We apply a kinetic Monte Carlo method to a
micromagnetic model describing the transition from superparamagnetic islands at
low coverages to a closed ferromagnetic film. The magnetic relaxation and the
island growth happen simultaneously. Near the percolation threshold a
metastable magnetic domain structure is obtained with an average domain area
ranging between the area of individual magnetic islands and the area of the
large domains observed for thicker ferromagnetic films. We conclude that this
micro-domain structure is controlled and stabilized by the nonuniform atomic
nanostructure of the ultrathin film, causing a random interaction between
magnetic islands with varying sizes and shapes. The average domain area and
domain roughness are determined. A maximum of the domain area and a minimum of
the domain roughness are obtained as a function of the temperature.

</DOC>
<DOC>
<DOCNO> 13524 </DOCNO>
Fluctuating Elastic Rings: Statics and Dynamics


  We study the effects of thermal fluctuations on elastic rings. Analytical
expressions are derived for correlation functions of Euler angles, mean square
distance between points on the ring contour, radius of gyration, and
probability distribution of writhe fluctuations. Since fluctuation amplitudes
diverge in the limit of vanishing twist rigidity, twist elasticity is essential
for the description of fluctuating rings. We find a crossover from a small
scale regime in which the filament behaves as a straight rod, to a large scale
regime in which spontaneous curvature is important and twist rigidity affects
the spatial configurations of the ring. The fluctuation-dissipation relation
between correlation functions of Euler angles and response functions, is used
to study the deformation of the ring by external forces. The effects of inertia
and dissipation on the relaxation of temporal correlations of writhe
fluctuations, are analyzed using Langevin dynamics.

</DOC>
<DOC>
<DOCNO> 13957 </DOCNO>
The Volatility in a Multi-share Financial Market Model


  Single index financial market models cannot account for the empirically
observed complex interactions between shares in a market. We describe a
multi-share financial market model and compare characteristics of the
volatility, that is the standard deviation of the price fluctuations, with
empirical characteristics. In particular we find its probability distribution
is similar to a log normal distribution but with a long power-law tail for the
large fluctuations, and that the time development shows superdiffusion. Both
these results are in good quantitative agreement with observations.

</DOC>
<DOC>
<DOCNO> 84541 </DOCNO>
Spin half in classical general relativity


  It is shown that models of elementary particles in classical general
relativity (geons) will naturally have the transformation properties of a
spinor if the spacetime manifold is not time orientable. From a purely
pragmatic interpretation of quantum theory this explains why spinor fields are
needed to represent particles. The models are based entirely on classical
general relativity and are motivated by the suggestion that the lack of a
time-orientation could be the origin of quantum phenomena.

</DOC>
<DOC>
<DOCNO> 40203 </DOCNO>
Measurement of branching fractions for two-body charmless B decays to


  We present preliminary results of a search for charmless two-body B decays to
charged pions and kaons using data collected by the BABAR detector at the
Stanford Linear Accelerator Center's PEP-II storage ring. In a sample of 8.8
million produced B-anti-B pairs we measure the branching fractions B(B^0 -->
pi^+pi^-) = (9.3^{+2.6}_{-2.3}^{+1.2}_{-1.4}) x 10^{-6} and B(B^0 --> K^+\pi^-)
= (12.5^{+3.0}_{-2.6}^{+1.3}_{-1.7}) x 10^{-6}, where the first uncertainty is
statistical and the second is systematic. For the decay B^0 --> K^+K^- we find
no significant signal and set an upper limit of B(B^0 --> K^+K^-) < 6.6 x
10^{-6} at the 90% confidence level.

</DOC>
<DOC>
<DOCNO> 12818 </DOCNO>
Integrable Lattices: Random Matrices and Random Permutations


  These lectures present a survey of recent developments in the area of random
matrices (finite and infinite) and random permutations. These probabilistic
problems suggest matrix integrals (or Fredholm determinants), which arise very
naturally as integrals over the tangent space to symmetric spaces, as integrals
over groups and finally as integrals over symmetric spaces. An important part
of these lectures is devoted to showing that these matrix integrals, upon
apropriately adding time-parameters, are natural tau-functions for integrable
lattices, like the Toda, Pfaff and Toeplitz lattices, but also for integrable
PDE's, like the KdV equation. These matrix integrals or Fredholm determinants
also satisfy Virasoro constraints, which combined with the integrable equations
lead to (partial) differential equations for the original probabilities.

</DOC>
<DOC>
<DOCNO> 117835 </DOCNO>
Super star clusters as probes of massive star evolution and the IMF at


  Young super star clusters and young compact massive star forming regions can
provide useful information on their burst properties (age, burst duration,
SFR), the upper end of the IMF and yield new constraints on the evolution of
massive stars. Through the study of their stellar populations we can in
particular extend our knowledge on massive stars to extreme metallicities
unavailable for such stars in the Local Group.
  Here we summarise the main results from recent studies on two metallicity
extremes: Wolf-Rayet and O star populations in very metal-poor BCD, and
metal-rich compact nuclear SF regions.

</DOC>
<DOC>
<DOCNO> 9305 </DOCNO>
The Nasdaq crash of April 2000: Yet another example of log-periodicity


  The Nasdaq Composite fell another $\approx 10 %$ on Friday the 14'th of April
2000 signaling the end of a remarkable speculative high-tech bubble starting in
spring 1997. The closing of the Nasdaq Composite at 3321 corresponds to a total
loss of over 35% since its all-time high of 5133 on the 10'th of March 2000.
Similarities to the speculative bubble preceding the infamous crash of October
1929 are quite striking: the belief in what was coined a ``New Economy'' both
in 1929 and presently made share-prices of companies with three digits
price-earning ratios soar. Furthermore, we show that the largest draw downs of
the Nasdaq are outliers with a confidence level better than 99% and that these
two speculative bubbles, as well as others, both nicely fit into the
quantitative framework proposed by the authors in a series of recent papers.

</DOC>
<DOC>
<DOCNO> 70920 </DOCNO>
Boltzmann Suppression of Interacting Heavy Particles


  Matsumoto and Yoshimura have recently argued that the number density of heavy
particles in a thermal bath is not necessarily Boltzmann-suppressed for T << M,
as power law corrections may emerge at higher orders in perturbation theory.
This fact might have important implications on the determination of WIMP relic
densities. On the other hand, the definition of number densities in a
interacting theory is not a straightforward procedure. It usually requires
renormalization of composite operators and operator mixing, which obscure the
physical interpretation of the computed thermal average. We propose a new
definition for the thermal average of a composite operator, which does not
require any new renormalization counterterm and is thus free from such
ambiguities. Applying this definition to the model of Matsumoto and Yoshimura
we find that it gives number densities which are Boltzmann-suppressed at any
order in perturbation theory. We discuss also heavy particles which are
unstable already at T=0, showing that power law corrections do in general
emerge in this case.

</DOC>
<DOC>
<DOCNO> 85029 </DOCNO>
Tidal Forces in Cold Black Hole Spacetimes


  We investigate here the behavior of a few spherically symmetric static
acclaimed black hole solutions in respect of tidal forces in the geodesic
frame. It turns out that the forces diverge on the horizon of cold black holes
(CBH) while for ordinary ones, they do not. It is pointed out that Kruskal-like
extensions do not render the CBH metrics nonsingular. We present a CBH that is
available in the Brans-Dicke theory for which the tidal forces do not diverge
on the horizon and in that sense it is a better one.

</DOC>
<DOC>
<DOCNO> 151663 </DOCNO>
Open Wilson Lines in Noncommutative Gauge Theory and Tomography of


  We study the issue of gauge-invariant observables in d=4, N=4 noncommutative
gauge theory and UV-IR relation therein. We show that open Wilson lines form a
complete set of gauge invariant operators, which are local in momentum space
and, depending on their size, exhibit two distinct behaviors of the UV-IR
relation. We next study these properties in a proposed dual description in
terms of supergravity and find agreement.

</DOC>
<DOC>
<DOCNO> 69941 </DOCNO>
Analyzing the 't Hooft Model on an x+ - p+ Lattice


  We study the 't Hooft model (large N_c QCD in 2 space-time dimensions) using
an improved approach to digitizing the sum of gauge theory Feynman diagrams
based on light-cone gauge A+=0 and discretized p+ and ix+. Our purpose is to
test the new formalism in a solvable case, with the hope to gain some insight
into how it might be usefully applied to the physically interesting case of 4
dimensional QCD.

</DOC>
<DOC>
<DOCNO> 151750 </DOCNO>
D-brane Couplings, RR Fields and Clifford Multiplication


  Non-trivial configurations of Yang-Mills fields and gravitational backgrounds
induce charges on Dp-branes that couple them to lower and higher RR potentials.
We show that these couplings can be described in a systematic and coordinate
independent way by using Clifford multiplication. In the minimal formulation,
D-brane charges and RR potentials combine into bispinors of an SO(1,9) which is
defined with a flat metric and does not coincide with the space-time Lorentz
group. In a non-minimal formulation, the RR potentials combine into SO(10,10)
spinors while the space of charges is formally enlarged to construct SO(10,10)
bispinors. The formalism suggests that the general form of the gravitational
contribution to the D-brane charges is not modified, though the replacement of
wedge product by Clifford multiplication gives rise to new couplings,
consistent with T-duality.

</DOC>
<DOC>
<DOCNO> 69626 </DOCNO>
Quark combinatorics for production ratios in hadronic Z^0 decays


  Model independent verification of the quark combinatorics rules, which govern
the ratios of the yields of secondaries, is presented for jet processes.
Because of a large number of produced resonances in the hadron jets, a test of
the quark combinatorics rules is hardly possible in the central region,
x_{hadron} < 0.2. However, a model-independent verification is plausible at
x_{hadron} \sim 1. It is shown that for the large x_{hadron} kinematical region
the quark combinatorial relations are in a reasonable agreement with data for
\rho^0/\pi^0 and p/\pi^+ ratios.

</DOC>
<DOC>
<DOCNO> 117269 </DOCNO>
Thermodynamics of Na_8 and Na_{20} clusters studied with ab-initio


  We study the thermodynamics of Na_8 and Na_{20} clusters using
multiple-histogram methods and an ab initio treatment of the valence electrons
within density functional theory. We consider the influence of various electron
kinetic-energy functionals and pseudopotentials on the canonical ionic specific
heats. The results for all models we consider show qualitative similarities,
but also significant temperature shifts from model to model of peaks and other
features in the specific-heat curves. The use of phenomenological
pseudopotentials shifts the melting peak substantially (~ 50--100 K) when
compared to ab-initio results. It is argued that the choice of a good
pseudopotential and use of better electronic kinetic-energy functionals has the
potential for performing large time scale and large sized thermodynamical
simulations on clusters.

</DOC>
<DOC>
<DOCNO> 170194 </DOCNO>
Non-locality and quantum theory: new experimental evidence


  Starting from the late 60's many experiments have been performed to verify
the violation Bell's inequality by Einstein-Podolsky-Rosen (EPR) type
correlations. The idea of these experiments being that: (i) Bell's inequality
is a consequence of locality, hence its experimental violation is an indication
of non locality; (ii) this violation is a typical quantum phenomenon because
any classical system making local choices (either deterministic or random) will
produce correlations satisfying this inequality. Both statements (i) and (ii)
have been criticized by quantum probability on theoretical grounds (not
discussed in the present paper) and the experiment discussed below has been
devised to support these theoretical arguments. We emphasize that the goal of
our experiment is not to reproduce classically the EPR correlations but to
prove that there exist perfectly local classical dynamical systems violating
Bell's inequality.

</DOC>
<DOC>
<DOCNO> 121339 </DOCNO>
Modelling CO emission from Mira's wind


  We have modelled the circumstellar envelope of {\it o} Ceti (Mira) using new
observational constraints. These are obtained from photospheric light scattered
in near-IR vibrational-rotational lines of circumstellar CO molecules at 4.6
micron: absolute fluxes, the radial dependence of the scattered intensity, and
two line ratios. Further observational constraints are provided by ISO
observations of far-IR emission lines from highly excited rotational states of
the ground vibrational state of CO, and radio observations of lines from
rotational levels of low excitation of CO. A code based on the Monte-Carlo
technique is used to model the circumstellar line emission.
  We find that it is possible to model the radio and ISO fluxes, as well as the
highly asymmetric radio-line profiles, reasonably well with a spherically
symmetric and smooth stellar wind model. However, it is not possible to
reproduce the observed NIR line fluxes consistently with a `standard model' of
the stellar wind. This is probably due to incorrectly specified conditions of
the inner regions of the wind model, since the stellar flux needs to be larger
than what is obtained from the standard model at the point of scattering, i.e.,
the intermediate regions at approximately 100-400 stellar radii (2"-7") away
from the star. Thus, the optical depth in the vibrational-rotational lines from
the star to the point of scattering has to be decreased. This can be
accomplished in several ways. For instance, the gas close to the star (within
approximately 2") could be in such a form that light is able to pass through,
either due to the medium being clumpy or by the matter being in radial
structures (which, further out, developes into more smooth or shell-like
structures).

</DOC>
<DOC>
<DOCNO> 85135 </DOCNO>
Data conditioning for gravitational wave detectors: A Kalman filter for


  Interferometric gravitational wave detectors operate by sensing the
differential light travel time between free test masses. Correspondingly, they
are sensitive to anything that changes the physical distance between the test
masses, including physical motion of the masses themselves. In ground-based
detectors the test masses are suspended as pendula and, consequently, thermal
or other excitations of the suspension wires' violin modes lead to a strong,
albeit narrow-band, ``signal'' in the detector wave-band that can confound
attempts to observe gravitational waves.
  Here we describe the design of a Kalman filter that determines the
time-dependent vibrational state of a detector's suspension ``violin'' modes
from the detector output. From the estimated state we can predict that
component of the detector output due to suspension excitations, thermal or
otherwise, and subtractively remove those disturbances from the detector
output. We demonstrate the filter's effectiveness both through numerical
simulations and application to real data taken on the LIGO 40 M prototype
detector.

</DOC>
<DOC>
<DOCNO> 10575 </DOCNO>
Exact Solution of the one-impurity quantum Hall problem


  The problem of a non-relativistic electron in the presence of a uniform
electromagnetic field and of one impurity, described by means of an
Aharonov-Bohm point-like vortex, is studied. The exact solution is found and
the quantum Hall's conductance turns out to be the same as in the impurity-free
case. This exactly solvable model seems to give indications, concerning the
possible microscopic mechanisms underlying the integer quantum Hall effect,
which sensibly deviate from some proposals available in the literature.

</DOC>
<DOC>
<DOCNO> 152288 </DOCNO>
Quantum Deformations of Space-Time SUSY and Noncommutative Superfield


  We review shortly present status of quantum deformations of Poincar\'{e} and
conformal supersymmetries. After recalling the $\kappa$-deformation of
$\hbox{D=4}$ Poincar\'{e} supersymmetries we describe the corresponding star
product multiplication for chiral superfields. In order to describe the
deformation of chiral vertices in momentum space the integration formula over
$\kappa$-deformed chiral superspace is proposed.

</DOC>
<DOC>
<DOCNO> 84685 </DOCNO>
A class of perfect-fluid cosmologies with polarised Gowdy symmetry and a


  We prove the existence of a class of perfect-fluid cosmologies with polarised
 Gowdy symmetry and a Kasner-like singularity. These solutions of the Einstein
equations depend on four free functions of one space coordinate and are
constructed by solving a system of Fuchsian equations.

</DOC>
<DOC>
<DOCNO> 120349 </DOCNO>
On the compared accuracy and reliability of spectroscopic and


  We present a comparison between the spectroscopic catalog of the HDF recently
published by Cohen et al and the redshifts measured by our group for those
objects using photometric techniques. We perform this comparison in order to
characterize the errors associated to the photometric redshift technique. The
spectroscopic sample includes over 140 objects in the HDF proper, representing
the deepest, cleanest, most complete spectroscopic catalog ever compiled. We
study each object for which our redshift and the one measured by Cohen et al
disagree. In most cases the photometric evidence is strong enough to call for a
careful review of the spectroscopic values, as they seem to be in error. It is
possible to characterize the systematic errors associated to our technique,
which when combined with the photometric errors allow us to obtain complete
information on the redshift of each galaxy and its associated confidence
interval, regardless of apparent magnitude. One of the main conclusions of this
study is that, to date, all the redshifts from our published catalog that have
been checked have been shown to be correct (within the stated confidence
limits). This implies that our galaxy template set is a fair representation of
the galaxy population at all redshifts (0<z<6) and magnitudes (R<24) explored
to date. On the other hand, spectroscopy of faint sources is subject to unknown
and uncharacterized systematic errors, that will in turn be transmitted to any
photometric redshift technique which uses spectroscopic samples as calibration.
Our analysis proves that photometric redshift techniques can and must be used
to extend the range of applicability of the spectroscopic redshift
measurements. (Abridged)

</DOC>
<DOC>
<DOCNO> 69875 </DOCNO>
The CKM Matrix and the Heavy Quark Expansion


  These lectures contain an elementary introduction to heavy quark symmetry and
the heavy quark expansion. Applications such as the expansion of heavy meson
decay constants and the treatment of inclusive and exclusive semileptonic B
decays are included. The use of heavy quark methods for the extraction of
|V_cb| and |V_ub| is presented is some detail.

</DOC>
<DOC>
<DOCNO> 120310 </DOCNO>
The Discovery of Broad P Cygni X-ray Lines from Circinus X-1 with the


  We present the first grating-resolution X-ray spectra of the X-ray binary Cir
X-1, obtained with the High Energy Transmission Grating Spectrometer on
Chandra. These reveal a rich set of lines from H-like and/or He-like Ne, Mg,
Si, S and Fe detected with a high signal-to-noise ratio. The lines are broad
(+/- 2000 km/s) and show P Cygni profiles. The absorption components of the
lines extend to low velocity, and they have about the same widths and strengths
as the corresponding emission components. The widths of the X-ray P Cygni lines
are comparable to that of the broad component of the strong, asymmetric H-alpha
line from Cir X-1, suggesting that the two phenomena may be related. We discuss
outflow models and propose that the P Cygni profiles may arise in the moderate
temperature (5 x 10^6 K) region of the wind from an X-ray heated accretion
disk. This basic picture strengthens the idea that the accretion disk in Cir
X-1 is viewed in a relatively edge-on manner, and it suggests that Cir X-1 is
the X-ray binary analog of a Broad Absorption Line quasar.

</DOC>
<DOC>
<DOCNO> 40619 </DOCNO>
First Electrooptical Detection of Charged Particles


  We have made the first observation of a charged particle beam by means of its
electro-optical effect on the polarization of laser light in a birefringent
crystal. The modulation of the laser light during the passage of a pulsed
electron beam was observed using a fast photodiode and a digital oscilloscope.
The fastest rise time measured in a single shot, 120 ps, was limited by the
bandwidth of the oscilloscope and the associated electronics. This technology
holds promise for detectors of greatly improved spatial and temporal resolution
for single relativistic charged particles as well as particle beams.

</DOC>
<DOC>
<DOCNO> 9400 </DOCNO>
Cooperative motion in Lennard-Jones binary mixtures below the glass


  Using the activation-relaxation technique (ART), we study the nature of
relaxation events in a binary Lennard-Jones system above and below the glass
transition temperature (T_g). ART generates trajectories with almost identical
efficiency at all temperature, thus avoiding the exponential slowing down below
T_g and providing extensive sampling everywhere. Comparing these runs, we find
that the number of atoms involved in an event decreases strongly with
temperature. In particular, while in the supercooled liquid activated events
are collective, involving on average thirty atoms or more, events below T_g
involve mostly single atoms and produce minimal disturbance of the local
environment. These results confirm the interpretation and the generality of
recent NMR results by Tang et al (Nature 402, 160 (1999)).

</DOC>
<DOC>
<DOCNO> 40560 </DOCNO>
Search for Rare 3 and 4-Body D0 Decays at FNAL E791


  Limits at the 10**-4 level are reported for rare and forbidden decays of the
D0 charm meson to a pair of leptons and either a vector meson or two
pseudoscalar mesons. Of these searches, 18 are investigations of decays without
previous published results; several others have significantly improved
sensitivity over previous results.

</DOC>
<DOC>
<DOCNO> 102856 </DOCNO>
Schematization of homotopy types


  The main goal of the present work is to give two precises interpretations as
well as two solutions to the "schematization problem" introduced by A.
Grothendieck in "Pursuing stacks". For the first of this interpretation, we
will introduce a category of "affine stacks over a ring k", which is the
smallest full sub-category of the homotopy category of simplicial presheaves on
the site of affine k-schemes, which contains the $K(G_{a},n)$ and which is
stable by homotopy limits. We show that the derived functor of global sections
from the category of affine stacks to the homotopy category of simplicial sets
possesses a left adjoint $X \mapsto (X\otimes k)^{uni}$. We will also show that
when $X$ is nilpotent and of finite type, $(X\otimes Q)^{uni}$ is a model for
the rational homotopy type of $X$, and $(X\otimes F_{p})^{uni}$ a model for its
p-adic homotopy type.
  For the second interpretation, we introduce a second sub-category of the
homotopy category of simplicial presheaves on the site of affine schemes over a
field $k$, the category of "schematic homotopy types". These objects are
essentially the pointed and connected simplicial presheaves $F$, such that
$\pi_{i}(F,*)$ is an affine group scheme which is unipotent if $i>1$. We will
show that the derived functor from the category of schematic homotopy types to
the homotopy category of pointed simplicial sets possesses a left adjoint $X
\mapsto (X\otimes k)^{sch}$. This last construction seems a good substitute of
the rational and p-adic homotopy theories for non-nilpotent spaces.

</DOC>
<DOC>
<DOCNO> 117471 </DOCNO>
Distribution of binary mergers around galaxies


  We use a stellar binary population synthesis code to find the lifetimes and
velocities of several types of possible GRB progenitors: double neutron stars,
black hole neutron stars, black hole white dwarfs, helium star mergers.
Assuming that they are born in different types of galaxies we compute their
spatial distribution and compare it with the observed locations of GRB
afterglows within their hosts. We discuss constraints on the compact object
merger model of GRBs imposed by this comparison and find that the observations
of afterglows and their host galaxies appear inconsistent with the GRB compact
object merger model.

</DOC>
<DOC>
<DOCNO> 102228 </DOCNO>
GW Invariants and Invariant Quotients


  The article investigates the following question: given a projective variety X
acted on by a connected and reductive group G, which is the relationship
between the Gromov-Witten invariants of X and those of X//G? In this study we
shall also try to give an algebraic approach to the so called Hamiltonian
Gromov-Witten invariants which have appeared rather recenly in the literature.

</DOC>
<DOC>
<DOCNO> 84273 </DOCNO>
Statistical Lorentzian geometry and the closeness of Lorentzian


  I introduce a family of closeness functions between causal Lorentzian
geometries of finite volume and arbitrary underlying topology. When points are
randomly scattered in a Lorentzian manifold, with uniform density according to
the volume element, some information on the topology and metric is encoded in
the partial order that the causal structure induces among those points; one can
then define closeness between Lorentzian geometries by comparing the sets of
probabilities they give for obtaining the same posets. If the density of points
is finite, one gets a pseudo-distance, which only compares the manifolds down
to a finite volume scale, as illustrated here by a fully worked out example of
two 2-dimensional manifolds of different topology; if the density is allowed to
become infinite, a true distance can be defined on the space of all Lorentzian
geometries. The introductory and concluding sections include some remarks on
the motivation for this definition and its applications to quantum gravity.

</DOC>
<DOC>
<DOCNO> 119291 </DOCNO>
Exploring the high frequency emission of radio loud X-ray binaries


  We report millimetre-wave continuum observations of the X-ray binaries Cygnus
X-3, SS 433, LSI+61 303, Cygnus X-1 and GRS 1915+105. The observations were
carried out with the IRAM 30 m-antenna at 250 GHz (1.25 mm) from 1998 March 14
to March 20. These millimetre measurements are complemented with centimetre
observations from the Ryle Telescope, at 15 GHz (2.0 cm) and from the Green
Bank Interferometer at 2.25 and 8.3 GHz (13 and 3.6 cm). Both Cygnus X-3 and SS
433 underwent moderate flaring events during our observations, whose main
spectral evolution properties are described and interpreted. A significant
spectral steepening was observed in both sources during the flare decay, that
is likely to be caused by adiabatic expansion, inverse Compton and synchrotron
losses. Finally, we also report 250 GHz upper limits for three additional
undetected X-ray binary stars: LSI+65 010, LSI+61 235 and X Per.

</DOC>
<DOC>
<DOCNO> 121321 </DOCNO>
Radial arc statistics: A new powerful probe of the central density


  We show that an expected number ratio of radial arcs (gravitationally lensed
images whose major axes lie in the radial direction of a cluster-lens
potential) to tangential arcs (gravitationally lensed images whose major axes
lie in the tangential direction) has strong dependence on the central density
profile of galaxy clusters and has little dependence on other parameters, e.g.
cluster temperature, background source galaxy redshift etc.. A comparison of
the expected number ratios with observed ratios provides a robust test to
constrain the central density profile of galaxy clusters. A tentative
comparison with the observational data shows that the central density profile
of galaxy clusters is r^{-1} - r^{-1.5}. This result indicates that the dark
matter is collisionless at least on cluster scale. Our result gives an upper
limit on a collision cross-section of self-interaction of dark matter
sigma_coll as sigma_coll/m < 0.1 cm^2/g where m is a dark matter particle mass.

</DOC>
<DOC>
<DOCNO> 68357 </DOCNO>
Confinement and short distance physics


  We consider non-perturbative effects at short distances in theories with
confinement. The analysis is straightforward within the Abelian models in which
the confinement arises on classical level. In all cases considered (compact
U(1) in 3D and 4D, dual Abelian Higgs model) there are non-perturbative
contributions associated with short distances which are due to topological
defects. In QCD case, both classical and quantum effects determine the role of
the topological defects and the theoretical analysis has not been completed so
far. Generically, the topological defects would result in 1/Q^2 corrections
going beyond the standard Operator Product Expansion. We review existing data
on the power corrections and find that the data favor existence of the novel
corrections, at least at the mass scale of (1-2) GeV. We indicate crucial
experiments which could further clarify the situation on the phenomenological
side.

</DOC>
<DOC>
<DOCNO> 85576 </DOCNO>
Indeterminism and Time Symmetry are Incompatible: Reply to Rebilas


  Rebilas argues that time-reversal can occur even in an indeterministic
system. This hypothesis is untestable, hence lying beyond physics.

</DOC>
<DOC>
<DOCNO> 80976 </DOCNO>
Asymptotically free theories based on discrete subgroups


  We study the critical behavior of discrete spin models related to the 2d O(3)
non-linear sigma model. Precise numerical results suggest that models with
sufficiently large discrete subgroups are in the same universality class as the
original sigma model. We observe that at least up to correlation lengths
$\xi\approx 300$ the cut-off effects follow effectively an $\propto a$
behaviour both in the O(3) and in the dodecahedron model.

</DOC>
<DOC>
<DOCNO> 69305 </DOCNO>
Particle versus Field Structure in Conformal Quantum Field Theories


  I show that a particle structure in conformal field theory is incompatible
with interactions. As a substitute one has particle-like exitations whose
interpolating fields have in addition to their canonical dimension an anomalous
contribution. The spectra of anomalous dimension is given in terms of the
Lorentz invariant quadratic invariant (compact mass operator) of a conformal
generator $R_{\mu}$ with pure discrete spectrum. The perturbative reading of
$R_{0\text{}}$as a Hamiltonian in its own right i.e. associated with an action
in a functional integral setting naturally leads to the AdS formulation. The
formal service role of AdS in order to access CQFT by a standard perturbative
formalism (without being forced to understand first massive theories and then
taking their scale-invariant limit) vastly increases the realm of
conventionally accessible 4-dim. CQFT beyond those for which one had to use
Lagrangians with supersymmetry in order to have a vanishing Beta-function.

</DOC>
<DOC>
<DOCNO> 100847 </DOCNO>
Semigroups, rings, and Markov chains


  We analyze random walks on a class of semigroups called ``left-regular
bands''. These walks include the hyperplane chamber walks of Bidigare, Hanlon,
and Rockmore. Using methods of ring theory, we show that the transition
matrices are diagonalizable and we calculate the eigenvalues and
multiplicities. The methods lead to explicit formulas for the projections onto
the eigenspaces. As examples of these semigroup walks, we construct a random
walk on the maximal chains of any distributive lattice, as well as two random
walks associated with any matroid. The examples include a q-analogue of the
Tsetlin library. The multiplicities of the eigenvalues in the matroid walks are
``generalized derangement numbers'', which may be of independent interest.

</DOC>
<DOC>
<DOCNO> 151812 </DOCNO>
Light-Front Aspects of Chiral Symmetry


  Spontaneous chiral symmetry breaking and axial anomaly are studied in the
light-front formulation. The existence of multiple vacua and a Nambu-Goldstone
boson, both related to dynamical fermion zero modes, are demonstrated within a
simple sigma model with fermions. The Weyl gauge formulation and a consistent
gauge invariant point-splitting regularization, which includes the light front
time, are crucial for obtaining the anomaly in the massive Schwinger model and
QED(3+1).

</DOC>
<DOC>
<DOCNO> 7710 </DOCNO>
Generic Dynamic Scaling in Kinetic Roughening


  We study the dynamic scaling hypothesis in invariant surface growth. We show
that the existence of power-law scaling of the correlation functions (scale
invariance) does not determine a unique dynamic scaling form of the correlation
functions, which leads to the different anomalous forms of scaling recently
observed in growth models. We derive all the existing forms of anomalous
dynamic scaling from a new generic scaling ansatz. The different scaling forms
are subclasses of this generic scaling ansatz associated with bounds on the
roughness exponent values. The existence of a new class of anomalous dynamic
scaling is predicted and compared with simulations.

</DOC>
<DOC>
<DOCNO> 8857 </DOCNO>
Like-charge attraction through hydrodynamic interaction


  We demonstrate that the attractive interaction measured between like-charged
colloidal spheres near a wall can be accounted for by a nonequilibrium
hydrodynamic effect. We present both analytical results and Brownian dynamics
simulations which quantitatively capture the one-wall experiments of Larsen and
Grier (Nature 385, p. 230, 1997).

</DOC>
<DOC>
<DOCNO> 116516 </DOCNO>
A Brief Note on the Magnetic Effects of the Electron


  In this paper it is shown that a recent formulation of the electron in terms
of a Kerr-Newman type metric, exhibits a short range magnetic effect, as indeed
has been observed at Cornell, and also an Aharonov-Bohm type of an effect.

</DOC>
<DOC>
<DOCNO> 116371 </DOCNO>
Effective Field Theory for Pedestrians


  A pedagological introduction to effective field theory is presented.

</DOC>
<DOC>
<DOCNO> 40483 </DOCNO>
Beyond the Standard Model at Tevatron


  This article presents recent results of searches for physics beyond the
Standard Model using the CDF and the D$\not$O detector at the Fermilab Tevatron
Collider. All results shown correspond to analysis performed using the past
1992-1996 Fermilab Tevatron run I data (roughly $100$ $pb^{-1}$ per each
experiment). In particular we describe recent Tevatron searches for scalar top
in the $b+\ell+$missing-$E_{T}$ channel, for squark and gluinos using like-sign
dileptons (LS), for large extra space-time dimensions and the search for
leptoquarks and technicolor in the missing-$E_{T}$+heavy flavour jet events.
Tight limits on the existence of such models have been set.

</DOC>
<DOC>
<DOCNO> 99472 </DOCNO>
Towards cohomology of renormalization: bigrading the combinatorial Hopf


  The renormalization of quantum field theory twists the antipode of a
noncocommutative Hopf algebra of rooted trees, decorated by an infinite set of
primitive divergences. The Hopf algebra of undecorated rooted trees, ${\cal
H}_R$, generated by a single primitive divergence, solves a universal problem
in Hochschild cohomology. It has two nontrivial closed Hopf subalgebras: the
cocommutative subalgebra ${\cal H}_{\rm ladder}$ of pure ladder diagrams and
the Connes-Moscovici noncocommutative subalgebra ${\cal H}_{\rm CM}$ of
noncommutative geometry. These three Hopf algebras admit a bigrading by $n$,
the number of nodes, and an index $k$ that specifies the degree of primitivity.
In each case, we use iterations of the relevant coproduct to compute the
dimensions of subspaces with modest values of $n$ and $k$ and infer a simple
generating procedure for the remainder. The results for ${\cal H}_{\rm ladder}$
are familiar from the theory of partitions, while those for ${\cal H}_{\rm CM}$
involve novel transforms of partitions. Most beautiful is the bigrading of
${\cal H}_R$, the largest of the three. Thanks to Sloane's {\tt superseeker},
we discovered that it saturates all possible inequalities. We prove this by
using the universal Hochschild-closed one-cocycle $B_+$, which plugs one set of
divergences into another, and by generalizing the concept of natural growth
beyond that entailed by the Connes-Moscovici case. We emphasize the yet greater
challenge of handling the infinite set of decorations of realistic quantum
field theory.

</DOC>
<DOC>
<DOCNO> 71126 </DOCNO>
More Corrections to the Higgs Mass in Supersymmetry


  In supersymmetry, the Higgs quartic couplings is given by the sum in
quadrature of the weak gauge couplings. This leads to the prediction of a light
Higgs boson, which still holds when considering loop corrections from soft
supersymmetry breaking. However, another source of corrections, which
explicitly depends on the scale of the mediation of supersymmetrey breaking, is
from generic hard breaking terms. We show that these corrections can
significantly modify the Higgs mass prediction in models of low-energy
supersymmetry breaking, for example, gauge mediation. Conversely, the Higgs
mass measurement can be used to constrain the scale of mediation of
supersymmetry breaking.

</DOC>
<DOC>
<DOCNO> 85522 </DOCNO>
Vacuum spacetimes with an isometry


  In vacuum space-times the exterior derivative of a Killing vector field is a
two-form that satisfies Maxwell equations without electromagnetic sources.
Using the algebraic structure of this two-form we have set up a new formalism
for the study of vacuum space-times with an isometry.

</DOC>
<DOC>
<DOCNO> 152252 </DOCNO>
Scale Invariance in a Non-Abelian Chern-Simons-Matter Model


  The general method of reduction in the number of coupling parameters is
applied in a Chern-Simons-matter model with several independent couplings. We
claim that considering the asymptotic region, and expressing all dimensionless
coupling parameters as functions of the Chern-Simons coupling, it is possible
to show that all $\beta$-functions vanish to any order of perturbative series.
Therefore, the model is asymptotically scale invariant.

</DOC>
<DOC>
<DOCNO> 83208 </DOCNO>
PSPACE Reasoning for Graded Modal Logics


  We present a PSPACE algorithm that decides satisfiability of the graded modal
logic Gr(K_R)---a natural extension of propositional modal logic K_R by
counting expressions---which plays an important role in the area of knowledge
representation. The algorithm employs a tableaux approach and is the first
known algorithm which meets the lower bound for the complexity of the problem.
Thus, we exactly fix the complexity of the problem and refute an
ExpTime-hardness conjecture. We extend the results to the logic Gr(K_(R \cap
I)), which augments Gr(K_R) with inverse relations and intersection of
accessibility relations. This establishes a kind of ``theoretical benchmark''
that all algorithmic approaches can be measured against.

</DOC>
<DOC>
<DOCNO> 84920 </DOCNO>
Notes on Riemann geometry and integrable systems. Part IV


  The connection between multidimensional soliton equations and
three-dimensional Riemann space is discussed.

</DOC>
<DOC>
<DOCNO> 8995 </DOCNO>
Non-Fermi Liquid Behaviour, the BRST Identity in the Dense Quark-Gluon


  At sufficiently high baryon densities, the physics of a dense quark-gluon
plasma may be investigated through the tools of perturbative QCD. This approach
has recently been successfully applied to the study of color superconductivity,
where the dominant di-quark pairing interaction arises from one gluon exchange.
Screening in the plasma leads to novel behaviour, including a remarkable
non-BCS scaling of T_C, the transition temperature to the color superconducting
phase. Radiative corrections to one gluon exchange were previously considered
and found to affect T_C. In particular, the quark self-energy in a plasma leads
to non-Fermi liquid behaviour and suppresses T_C. However, at the same time,
the quark-gluon vertex was shown not to modify the result at leading order.
This dichotomy between the effects of the radiative corrections at first
appears rather surprising, as the BRST identity connects the self-energy to the
vertex corrections. Nevertheless, as we demonstrate, there is in fact no
contradiction with the BRST identity, at least to leading log order. This
clarifies some of the previous statements on the importance of the higher order
corrections to the determination of T_C and the zero temperature gap in color
superconductivity.

</DOC>
<DOC>
<DOCNO> 99536 </DOCNO>
Invertibility of Toeplitz + Hankel Operators and Singular Integral


  It is well known that a Toeplitz operator is invertible if and only if its
symbols admits a canonical Wiener-Hopf factorization, where the factors satisfy
certain conditions. A similar result holds also for singular integral
operators. More general, the dimension of the kernel and cokernel of Toeplitz
or singular integral operators which are Fredholm can be expressed in terms of
the partial indices of an associated Wiener-Hopf factorization problem.
  In this paper we establish corresponding results for Toeplitz + Hankel
operators and singular integral operators with flip under the assumption that
the generating functions are sufficiently smooth. We are led to a slightly
different factorization problem, in which so-called characteristic pairs
instead of the partial indices appear. These pairs provide the relevant
information about the dimension of the kernel and cokernel and thus answer the
invertibility problem.

</DOC>
<DOC>
<DOCNO> 102440 </DOCNO>
Asymptotic Hodge theory and quantum products


  Assuming suitable convergence properties for the Gromov-Witten potential of a
Calabi-Yau manifold $X$ one may construct a polarized variation of Hodge
structure over the complexified K\"ahler cone of $X$. In this paper we show
that, in the case of fourfolds, there is a correspondence between ``quantum
potentials'' and polarized variations of Hodge structures that degenerate to a
maximally unipotent boundary point. Under this correspondence, the WDVV
equations are seen to be equivalent to the Griffiths' trasversality property of
a variation of Hodge structure.

</DOC>
<DOC>
<DOCNO> 116780 </DOCNO>
Development of rebunching cavities at IAP


  A focus of work at IAP has been the development and optimization of spiral
loaded cavities since the 1970s [A. Schempp et al, NIM 135, 409 (1976)]. These
cavities feature a high efficiency, a compact design and a big variety of
possible fields of application. They find use both as bunchers and post
accelerators to vary the final energy of the beam. In comparison to other
available designs, the advantage of these structures lies in their small size.
Furthermore they can easily be tuned to the required resonance frequency by
varying the length of the spiral. Due to the small size of the cavities the
required budget can also be kept low. Here, two slightly different types of
spiral loaded cavities, which were built for the REX-ISOLDE project at CERN and
the intensity upgrade program at GSI are being discussed.

</DOC>
<DOC>
<DOCNO> 9138 </DOCNO>
Tunneling Spectroscopy of the Underdoped High-$T_{c}$ Superconductors


  Considering a possibility that the pseudogap state in the underdoped
high-$T_{c}$ superconductors is not due to a superconducting correlation, we
study the tunneling spectroscopy below $T_{c}$ based on the phenomenological
models of the pseudogap state. Specifically we consider two cases: (1) the
pseudogap is a simple suppression of the density of states with an unknown
origin; (2) the pseudogap state is due to an antiferromagnetic correlation. For
both cases we calculate $dI/dV$ using the BTK theory. The results are discussed
in comparison with experiments.

</DOC>
<DOC>
<DOCNO> 40522 </DOCNO>
Time Dependent $B_s^0 - \bar{B_s^0}$ Oscillations Using Exclusively


  We set a preliminary 95% C.L. exclusion on the oscillation frequency of
$B_s^0 - \bar{B_s^0}$ mixing using a sample of 400,000 hadronic $Z^0$ decays
collected by the SLD experiment at the SLC during the 1996-98 run. In this
analysis, $B_s^0$ mesons are partially reconstructed by combining a fully
reconstructed $D_s$ with other $B_s^0$ decay tracks. The $D_s$ decays are
reconstructed via the $\phi \pi$ and $K^* K$ channels. The $b$-hadron flavor at
production is determined by exploiting the large forward-backward asymmetry of
polarized $Z^0 \to b \bar{b}$ decays as well as information from the hemisphere
opposite to the reconstructed B decay. The flavor of the $B_s^0$ at the decay
vertex is determined by the charge of the $D_s$. A total of 361 candidates
passed the final event selection cuts. This analysis excludes the following
values of the $B_s^0 - \bar{B_s^0}$ mixing oscillation frequency: $\Delta m_s <
1.5$ ps$^{-1}$, $2.6 < \Delta m_s < 4.9$ ps$^{-1}$, and $10.8 < \Delta m_s <
13.5$ ps$^{-1}$ at the 95% confidence level.

</DOC>
<DOC>
<DOCNO> 85251 </DOCNO>
The phase of a quantum mechanical particle in curved spacetime


  We investigate the quantum mechanical wave equations for free particles of
spin 0,1/2,1 in the background of an arbitrary static gravitational field in
order to explicitly determine if the phase of the wavefunction is $S/\hbar =
\int p_{\mu} dx^{\mu} / \hbar$, as is often quoted in the literature. We work
in isotropic coordinates where the wave equations have a simple managable form
and do not make a weak gravitational field approximation. We interpret these
wave equations in terms of a quantum mechanical particle moving in medium with
a spatially varying effective index of refraction. Due to the first order
spatial derivative structure of the Dirac equation in curved spacetime, only
the spin 1/2 particle has \textit{exactly} the quantum mechanical phase as
indicated above. The second order spatial derivative structure of the spin 0
and spin 1 wave equations yield the above phase only to lowest order in
$\hbar$. We develop a WKB approximation for the solution of the spin 0 and spin
1 wave equations and explore amplitude and phase corrections beyond the lowest
order in $\hbar$. For the spin 1/2 particle we calculate the phase appropriate
for neutrino flavor oscillations.

</DOC>
<DOC>
<DOCNO> 120854 </DOCNO>
Linear Coasting in Cosmology and SNe Ia


  A strictly linear evolution of the cosmological expansion scale factor is a
characteristic feature in several classes of alternative gravity theories as
also in the standard (big-bang) model with specially chosen equations of state
of matter. Such an evolution has no free parameters as far as the classical
cosmological tests are concerned and should therefore be easily falsifiable. In
this article we demonstrate how such models present very good fits to the
current supernovae 1a data. We discuss the overall viability of such models.

</DOC>
<DOC>
<DOCNO> 68559 </DOCNO>
Holographic RG and Cosmology in Theories with Quasi-Localized Gravity


  We study the long distance behaviour of brane theories with quasi-localized
gravity. The 5D effective theory at large scales follows from a holographic
renormalization group flow. As intuitively expected, the graviton is
effectively four dimensional at intermediate scales and becomes five
dimensional at large scales. However in the holographic effective theory the
essentially 4D radion dominates at long distances and gives rise to scalar
anti-gravity. The holographic description shows that at large distances the GRS
model is equivalent to the model recently proposed by Dvali, Gabadadze and
Porrati (DGP), where a tensionless brane is embedded into 5D Minkowski space,
with an additional induced 4D Einstein-Hilbert term on the brane. In the
holographic description the radion of the GRS model is automatically localized
on the tensionless brane, and provides the ghost-like field necessary to cancel
the extra graviton polarization of the DGP model. Thus, there is a holographic
duality between these theories. This analysis provides physical insight into
how the GRS model works at intermediate scales; in particular it sheds light on
the size of the width of the graviton resonance, and also demonstrates how the
holographic RG can be used as a practical tool for calculations.

</DOC>
<DOC>
<DOCNO> 72005 </DOCNO>
Relic neutrino asymmetry generation from $\nu_{\alpha}- \nu_s$


  Active--sterile neutrino oscillations provide a mechanism by which large
differences in the neutrino and antineutrino number densities can be created in
the early universe. The quantum kinetic equations are employed in the study of
these asymmetries, which, when solved analytically in the adiabatic limit,
generate physically transparent evolution equations that are very useful for
the understanding of the nature of the asymmetry growth.

</DOC>
<DOC>
<DOCNO> 120266 </DOCNO>
Emission-Line Properties of the Optical Filaments of NGC 1275


  Extended nebular filaments are seen at optical wavelengths in NGC 1275, the
central galaxy in the Perseus cluster. The agents responsible for the
excitation of these filaments remain poorly understood. In this paper we
investigate possible mechanisms for powering the filaments, using measurements
from an extensive spectroscopic data set acquired at the Lick Observatory 3-m
Shane telescope. The results show that the filaments are in an extremely low
ionization and excitation state. The high signal-to-noise ratio of the spectra
allows us to measure or place sensitive upper limits on weak but important
diagnostic lines. We compare the observed line intensity ratios to the
predictions of various ionization models, including photoionization by an
active galactic nucleus, shock heating, stellar photoionization, and
photoionization by the intracluster medium. We also investigate possible roles
for cluster extreme-ultraviolet emission, and filtering of cluster soft X-ray
emission by an ionized screen, in the energetics of the filaments. None of
these mechanisms provides an entirely satisfactory explanation for the physical
state of the nebulae. Heating and ionization by reconnection of the
intracluster magnetic field remains a potentially viable alternative, which
merits further investigation through Faraday rotation studies.

</DOC>
<DOC>
<DOCNO> 70254 </DOCNO>
Constituent quark masses from a modified perturbative QCD


  A recently proposed modified perturbative expansion for QCD incorporating
gluon condensation is employed to evaluate the quark and gluon self-energy
corrections in the first approximations. The results predict mass values of 1/3
of the nucleon mass for the light quarks u, d, and s and a monotonously growing
variation with the current mass. The only phenomenological input consists in
that <G^2> is evaluated up to order g^2 as a function of the unique parameter C
defining the modified propagator and then C is fixed to give a current estimate
of <g^2 G^2>. The light quarks u and d result to be confined and the s, c, b
and t ones show damped propagation modes, then suggesting a model for the large
differences in stability between the nucleons and the higher resonances. The
above properties of quark modes diverge from the fully confinement result
following from the similar gluon propagator previously considered by Munczek
and Nemirovski. On another hand, the condensate effects on the gluon
self-energy furnish a tachionic mass shell as predicted by the Fukuda analysis
of gluon condensation in QCD.

</DOC>
<DOC>
<DOCNO> 40576 </DOCNO>
Recent Structure Function Results from CCFR


  A new structure function analysis of CCFR deep inelastic nu-N and nubar-N
scattering data is presented for previously unexplored kinematic regions down
to Bjorken x=0.0045 and Q^2=0.3 GeV^2. Comparisons to charged lepton scattering
data from NMC and E665 experiments are made and the behavior of the structure
function F2_nu is studied in the limit Q^2 -> 0

</DOC>
<DOC>
<DOCNO> 117419 </DOCNO>
Phase Lag and Coherence Function of X-ray emission from Black Hole


  We report the results from measuring the phase lag and coherence function of
X-ray emission from black hole candidate (BHC) XTE J1550-564. These X-ray
temporal properties have been recognized to be increasingly important in
providing important diagnostics of the dynamics of accretion flows around black
holes. For XTE J1550-564, we found significant hard lag --- the X-ray
variability in high energy bands {\em lags} behind that in low energy bands ---
associated both with broad-band variability and quasi-periodic oscillation
(QPO). However, the situation is more complicated for the QPO: while hard lag
was measured for the first harmonic of the signal, the fundamental component
showed significant {\em soft} lag. Such behavior is remarkably similar to what
was observed of microquasar GRS 1915+105. The phase lag evolved during the
initial rising phase of the 1998 outburst. The magnitude of both the soft and
hard lags of the QPO increases with X-ray flux, while the Fourier spectrum of
the broad-band lag varies significantly in shape. The coherence function is
relatively high and roughly constant at low frequencies, and begins to drop
almost right after the first harmonic of the QPO. It is near unity at the
beginning and decreases rapidly during the rising phase. Also observed is that
the more widely separated the two energy bands are the less the coherence
function between the two. It is interesting that the coherence function
increases significantly at the frequencies of the QPO and its harmonics. We
discuss the implications of the results on the models proposed for BHCs.

</DOC>
<DOC>
<DOCNO> 151957 </DOCNO>
Compactified NCOS and duality


  We study four-dimensional U(1) on a non-commutative T^2 with rational Theta.
This theory has dual descriptions as ordinary SYM or as NCOS. We identify a set
of massive non-interacting KK states in the SYM theory and track them through
the various dualities. They appear as stretched strings in the non-commutative
U(1) providing another example of the IR/UV mixing in non-commutative field
theories. In the NCOS these states appear as D-strings with winding and
momentum. They form an unconventional type of 1/4 BPS state with the 3-brane.
To obtain a consistent picture of S-duality for compactified theories it is
essential to keep track of both the NS and the RR B-fields.

</DOC>
<DOC>
<DOCNO> 102055 </DOCNO>
Galois Groups Over Nonrigid Fields


  Let $F$ be a field with characteristic $\neq 2$. We show that $F$ is a
nonrigid field if and only if certain small 2-groups occur as Galois groups
over $F$. These results provide new "automatic realizability" results for
Galois groups over $F$. The groups we consider demonstrate the inequality of
two particular metabelian 2-extensions of $F$ which are unequal precisely when
$F$ is a nonrigid field. Using known results on connections between rigidity
and existence of certain valuations, we obtain Galois-theoretic criteria for
the existence of these valuations.

</DOC>
<DOC>
<DOCNO> 72121 </DOCNO>
Electroweak Sudakov corrections


  At energies much larger than the mass of the weak gauge bosons, electroweak
radiative corrections can lead to significant corrections. At 1 TeV the one
loop corrections can be of ${\cal O} (20 %)$ due to large contributions of the
Sudakov type. We summarize recent progress in the evaluation and resummation of
the double and single logarithmic corrections to general scattering amplitudes
for fermions, transversely as well as longitudinally polarized external lines.

</DOC>
<DOC>
<DOCNO> 84477 </DOCNO>
Quantization of Constrained Systems


  The present article is primarily a review of the projection-operator approach
to quantize systems with constraints. We study the quantization of systems with
general first- and second-class constraints from the point of view of
coherent-state, phase-space path integration, and show that all such cases may
be treated, within the original classical phase space, by using suitable
path-integral measures for the Lagrange multipliers which ensure that the
quantum system satisfies the appropriate quantum constraint conditions. Unlike
conventional methods, our procedures involve no $\delta$-functionals of the
classical constraints, no need for dynamical gauge fixing of first-class
constraints nor any average thereover, no need to eliminate second-class
constraints, no potentially ambiguous determinants, as well as no need to add
auxiliary dynamical variables expanding the phase space beyond its original
classical formulation, including no ghosts. Besides several pedagogical
examples, we also study: (i) the quantization procedure for reparameterization
invariant models, (ii) systems for which the original set of Lagrange
mutipliers are elevated to the status of dynamical variables and used to define
an extended dynamical system which is completed with the addition of suitable
conjugates and new sets of constraints and their associated Lagrange
multipliers, (iii) special examples of alternative but equivalent formulations
of given first-class constraints, as well as (iv) a comparison of both regular
and irregular constraints.

</DOC>
<DOC>
<DOCNO> 122555 </DOCNO>
Tidal stirring and the origin of dwarf spheroidals in the Local Group


  N-Body/SPH simulations are used to study the evolution of dwarf irregular
galaxies (dIrrs) entering the dark matter halo of the Milky Way or M31 on
plunging orbits. We propose a new dynamical mechanism driving the evolution of
gas rich, rotationally supported dIrrs, mostly found at the outskirts of the
Local Group (LG), into gas free, pressure supported dwarf spheroidals (dSphs)
or dwarf ellipticals (dEs), observed to cluster around the two giant spirals.
The initial model galaxies are exponential disks embedded in massive dark
matter halos and reproduce nearby dIrrs. Repeated tidal shocks at the
pericenter of their orbit partially strip their halo and disk and trigger
dynamical instabilities that dramatically reshape their stellar component.
After only 2-3 orbits low surface brightness (LSB) dIrrs are transformed into
dSphs, while high surface brightness (HSB) dIrrs evolve into dEs. This
evolutionary mechanism naturally leads to the morphology-density relation
observed for LG dwarfs. Dwarfs surrounded by very dense dark matter halos, like
the archetypical dIrr GR8, are turned into Draco or Ursa Minor, the faintest
and most dark matter dominated among LG dSphs. If disks include a gaseous
component, this is both tidally stripped and consumed in periodic bursts of
star formation. The resulting star formation histories are in good qualitative
agreement with those derived using HST color-magnitude diagrams for local
dSphs.

</DOC>
<DOC>
<DOCNO> 102396 </DOCNO>
The Sign Representation for Shephard Groups


  Shephard groups are unitary reflection groups arising as the symmetries of
regular complex polytopes. For a Shephard group, we identify the representation
carried by the principal ideal in the coinvariant algebra generated by the
image of the product of all linear forms defining reflecting hyperplanes. This
representation turns out to have many equivalent guises making it analogous to
the sign representation of a finite Coxeter group. One of these guises is (up
to a twist) the cohomology of the Milnor fiber for the isolated singularity at
0 in the hypersurface defined by any homogeneous invariant of minimal degree.

</DOC>
<DOC>
<DOCNO> 120339 </DOCNO>
An excess of mid-IR luminous galaxies in Abell 1689?


  We present the results of infrared observations of Abell 1689 which was
observed with ISOCAM, at 6.7\mic and 15\mic, and ISOPHOT at 200\mic. The
cluster galaxies detected above a sensitivity limit of 0.15 mJy in the 6.7\mic
band, whose emission is mostly dominated by their stellar component, show
optical colors similar to the overall cluster population and are gathered in
the center of the cluster, following the distribution of the cluster
early-types. In the 15\mic band, above a sensitivity limit of 0.3 mJy, the
galaxies spectroscopically confirmed to be cluster members are blue outliers of
the cluster color-magnitude relation and become brighter going from the center
to the outer parts of the cluster.
  We compare the 6.7\mic and 15\mic fluxes and the cumulative distributions of
the B-[6.75] and B-[15] colors of the A1689 galaxies, above our 90%
completeness limits of 0.2 and 0.4 mJy for 6.7\mic and 15\mic respectively, to
the galaxies of two nearby clusters, Virgo and Coma, and to the field galaxies
at the same redshift of the cluster. Although the B-[6.7] color distributions
of the three clusters are compatible, we find a systematic excess of B-[15]
color distribution for the galaxies located in Abell 1689 with respect to Coma
or Virgo galaxies. This result proves the existence of a mid-infrared
equivalent of the Butcher-Oemler effect measured in the optical. The comparison
of 15\mic flux and B-[15] color distributions of A1689 and field galaxies does
not show strong differences between the population of starburst galaxies in the
cluster and in the field.

</DOC>
<DOC>
<DOCNO> 12829 </DOCNO>
High-momentum dynamic structure function of liquid 3He-4He mixtures: a


  The high-momentum dynamic structure function of liquid 3He-4He mixtures has
been studied introducing final state effects. Corrections to the impulse
approximation have been included using a generalized Gersch-Rodriguez theory
that properly takes into account the Fermi statistics of 3He atoms. The
microscopic inputs, as the momentum distributions and the two-body density
matrices, correspond to a variational (fermi)-hypernetted chain calculation.
The agreement with experimental data obtained at $q=23.1$ \AA$^{-1}$ is not
completely satisfactory, the comparison being difficult due to inconsistencies
present in the scattering measurements. The significant differences between the
experimental determinations of the 4He condensate fraction and the 3He kinetic
energy, and the theoretical results, still remain unsolved.

</DOC>
<DOC>
<DOCNO> 39877 </DOCNO>
Optimal-Observable Analysis of the Angular and Energy Distributions for


  An optimal-observable analysis of the angular and energy distributions of the
leptons and bottom quarks in the process e+e- --> tt-bar --> l^{+-}/b(b-bar)...
has been performed in order to measure the most general top-quark couplings to
gauge bosons at polarized linear colliders. The optimal beam polarization for
determination of each coupling has been found. A very sensitive test of CP
violation in tt-bar production and decay has been proposed.

</DOC>
<DOC>
<DOCNO> 150641 </DOCNO>
Duality between coordinates and Dirac field


  The duality between the Cartesian coordinates on the Minkowski space-time and
the Dirac field is investigated. Two distinct possibilities to define this
duality are shown to exist. In both cases, the equations satisfied by
prepotentials are of second order.

</DOC>
<DOC>
<DOCNO> 120011 </DOCNO>
On Batchelor passive advection by a finite-time correlated random


  The Batchelor passive advection is an advection by a smooth velocity field.
If the velocity field is a delta-correlated in time random Gaussian process,
then the problem is reduced to quantum mechanics of fluctuating velocity
gradient u'(t). For the finite-time correlated velocity field, such a reduction
does not exist. To illustrate this point, the second moment of a passively
advected magnetic field is considered, and the stochastic calculus is used to
find finite-time corrections to its growth rate. The growth rate depends on
large scale properties of the velocity field. Moreover, the problem is not
universal with respect to the short-time regularization: different
regularizations give different answers for the growth rate.

</DOC>
<DOC>
<DOCNO> 83317 </DOCNO>
Knowledge on Treelike Spaces


  This paper presents a bimodal logic for reasoning about knowledge during
knowledge acquisition. One of the modalities represents (effort during)
non-deterministic time and the other represents knowledge. The semantics of
this logic are tree-like spaces which are a generalization of semantics used
for modeling branching time and historical necessity. A finite system of axiom
schemes is shown to be canonically complete for the formentioned spaces. A
characterization of the satisfaction relation implies the small model property
and decidability for this system.

</DOC>
<DOC>
<DOCNO> 151398 </DOCNO>
Particle creation via relaxing hypermagnetic knots


  We demonstrate that particle production for fermions coupled chirally to an
Abelian gauge field like the hypercharge field is provided by the microscopic
mechanism of level crossing. For this purpose we use recent results on zero
modes of Dirac operators for a class of localized hypermagnetic knots.

</DOC>
<DOC>
<DOCNO> 71084 </DOCNO>
Charge-dependent nucleon-nucleon potential from chiral effective field


  We discuss charge symmetry and charge independence breaking in a chiral
effective field theory approach for few-nucleon systems based on a modified
Weinberg power counting. We construct a two-nucleon potential with bound and
scattering states generated by means of a properly regularized
Lippmann-Schwinger equation. We systematically introduce strong
isospin-violating and electromagnetic operators in the theory. We use standard
procedures to treat the Coulomb potential between two protons in momentum
space. We present results for phase shifts in the proton-proton, the
neutron-proton and the neutron-neutron systems. We discuss the various
contributions to charge dependence and charge symmetry breaking observed in the
nucleon-nucleon scattering lengths.

</DOC>
<DOC>
<DOCNO> 12149 </DOCNO>
Nucleation phenomena in a nonuniform atomic fluid in the electrical


  The density functional approach is used to study the gas-to-liquid and
liquid-to-gas nucleation phenomena in a fluid of two-level atoms in an external
electrical field. The influence of the field on the surface tension and
nucleation and cavitation barriers is discussed.

</DOC>
<DOC>
<DOCNO> 151767 </DOCNO>
BC_n Ruijsenaars-Schneider models: R-Matrix structure and hamiltonians


  This paper is replaced and superseded by nlin.SI/0106015 (Title: Structures
in BC_N Ruijsenaars-Schneider models)

</DOC>
<DOC>
<DOCNO> 102676 </DOCNO>
Characterizing Volume Forms


  Old and new results for characterizing volume forms in functional
integration.

</DOC>
<DOC>
<DOCNO> 122026 </DOCNO>
Spectrophotometry and period analysis of the sdB eclipsing binary HW


  New CCD observations of the pre-cataclysmic binary HW Virginis are presented
and discussed. The R-filtered CCD photometry was supplemented with medium-band
(Cousins VRI) spectrophotometry based on low-resolution objective-prism
spectra. The period variation is reanalysed by means of the standard O-C
technique. The new data support the conclusions of Kilkenny et al. (2000) on
the strong and continuous period change. The long-term period variation can be
described approximately with two linear branches in the O-C diagram
corresponding to a sudden period jump between two constant periods around JD
2448500 (1991). Additional smooth small-scale changes in the period distort the
linearity. The present data do not support the hypothetical light-time effect
of Cakirli & Devlen (1999). The eclipse depths in V, R, and I do not show
colour dependence, which suggests negligible continuum variations due to the
cool secondary component in the far-red region (up to 8800 AA). The magnitude
of the reflection effect was used to estimate the mean effective temperature of
the illuminated hemisphere of the secondary. The result is 13300\pm200 K or
11000\pm200 K, depending on the primary temperature (35000 K or 26000 K). An
albedo near unity is implied for the cool component.

</DOC>
<DOC>
<DOCNO> 71030 </DOCNO>
First-Order Chiral Phase Transition in High-Energy Collisions: Can


  We discuss homogeneous nucleation in a first-order chiral phase transition
within an effective field theory approach to low-energy QCD. Exact decay rates
and bubble profiles are obtained numerically and compared to analytic results
obtained with the thin-wall approximation. The thin-wall approximation
overestimates the nucleation rate for any degree of supercooling. The time
scale for critical thermal fluctuations is calculated and compared to typical
expansion times for high-energy hadronic or heavy-ion collisions. We find that
significant supercooling is possible, and the relevant mechanism for phase
conversion might be that of spinodal decomposition. Some potential experimental
signatures of supercooling, such as an increase in the correlation length of
the scalar condensate, are also discussed.

</DOC>
<DOC>
<DOCNO> 120170 </DOCNO>
CMB Observables and Their Cosmological Implications


  We show that recent measurements of the power spectrum of cosmic microwave
background anisotropies by BOOMERanG and MAXIMA can be characterized by four
observables, the position of the first acoustic peak l_1= 206 pm 6, the height
of the first peak relative to COBE normalization H_1= 7.6 pm 1.4, the height of
the second peak relative to the first H_2 = 0.38 pm 0.04, and the height of the
third peak relative to the first H_3 = 0.43 pm 0.07. This phenomenological
representation of the measurements complements more detailed likelihood
analyses in multidimensional parameter space, clarifying the dependence on
prior assumptions and the specific aspects of the data leading to the
constraints. We illustrate their use in the flat LCDM family of models, where
we find Omega_m h^{3.8} > 0.079 (or nearly equivalently, the age of the
universe t_0 < 13-14 Gyr) from l_1 and a baryon density Omega_b h^2 > 0.019, a
matter density Omega_m h^2 < 0.42 and tilt n>0.85 from the peak heights (95%
CL). With the aid of several external constraints, notably nucleosynthesis, the
age of the universe and the cluster abundance and baryon fraction, we construct
the allowed region in the (Omega_m,h) plane; it points to high h (0.6< h < 0.9)
and moderate Omega_m (0.25 < Omega_m < 0.6).

</DOC>
<DOC>
<DOCNO> 11335 </DOCNO>
One-point functions in perturbed boundary conformal field theories


  We consider the one-point functions of bulk and boundary fields in the
scaling Lee-Yang model for various combinations of bulk and boundary
perturbations. The one-point functions of the bulk fields are analysed using
the truncated conformal space approach and the form-factor expansion. Good
agreement is found between the results of the two methods, though we find that
the expression for the general boundary state given by Ghoshal and
Zamolodchikov has to be corrected slightly. For the boundary fields we use
thermodynamic Bethe ansatz equations to find exact expressions for the strip
and semi-infinite cylinder geometries. We also find a novel off-critical
identity between the cylinder partition functions of models with differing
boundary conditions, and use this to investigate the regions of
boundary-induced instability exhibited by the model on a finite strip.

</DOC>
<DOC>
<DOCNO> 12019 </DOCNO>
Reply to the comment on Low energy magnetic excitations of the


  Original paper from Mirebeau et al. PRL 83, 628, 1999 Comment from W. Bao et
al (cond-mat/0008042, 2 Aug 2000 submitted to PRL, updated on 1 sep 2000

</DOC>
<DOC>
<DOCNO> 8818 </DOCNO>
C-axis optical properties of high Tc cuprates


  A review is given of the experimental status of the interlayer coupling
energy in the cuprates. A second c-axis plasmon is identified in the double
layer compound Y123 for various dopings. The anomalous transport properties
along the c-direction and in the planar directions are compared to model
calculations based on strongly anisotropic scattering. An excellent description
of the optical data at optimal doping is obtained if an anomalously large
anisotropy of the scattering rate between cold spots and hot spots is assumed.
This raises questions as to the physical meaning of these parameters.

</DOC>
<DOC>
<DOCNO> 118903 </DOCNO>
Discovery of a Bright Field Methane (T-type) Brown Dwarf by 2MASS


  We report the discovery of a bright (J = 13.83$\pm$0.03) methane brown dwarf,
or T dwarf, by the Two Micron All Sky Survey. This object, 2MASSI
J0559191-140448, is the first brown dwarf identified by the newly commissioned
CorMASS instrument mounted on the Palomar 60-inch Telescope. Near-infrared
spectra from 0.9 - 2.35 $\micron$ show characteristic CH$_4$ bands at 1.1, 1.3,
1.6, and 2.2 $\micron$, which are significantly shallower than those seen in
other T dwarfs discovered to date. Coupled with the detection of an FeH band at
0.9896 $\micron$ and two sets of K I doublets at J-band, we propose that 2MASS
J0559-14 is a warm T dwarf, close to the transition between L and T spectral
classes. The brightness of this object makes it a good candidate for detailed
investigation over a broad wavelength regime and at higher resolution.

</DOC>
<DOC>
<DOCNO> 121493 </DOCNO>
A detailed two-dimensional stellar population study of M32


  We present Two-Dimensional Spectroscopy of the 9x12 arcsec^2 central region
of M32 obtained with the 2D_FIS fibre spectrograph installed at the William
Herschel Telescope. From these spectra line strength maps have been
reconstructed for about 20 absorption lines, mostly belonging to the Lick
system. We find good agreement with long-slit line strength profiles in the
literature. In contrast with previous studies, indices were azimuthally
averaged along continuum isophotes of M32. A remarkable result is that no
gradients are presented in the spectral indices. So, we have fitted the mean
values of each spectral index and central colours to the models of Vazdekis et
al. (1996) and Worthey (1994), finding that an intermediate age (~4 Gyr) and
metallicity similar to solar (Z=0.02) are the best fitted values for the
innermost region of M32.

</DOC>
<DOC>
<DOCNO> 151345 </DOCNO>
A remark on T-duality and quantum volumes of zero-brane moduli spaces


  T-duality (Fourier-Mukai duality) and properties of classical instanton
moduli spaces can be used to deduce some properties of
$\alpha^{\prime}$-corrected moduli spaces of branes for Type IIA string theory
compactified on $K3$ or $T^4$. Some interesting differences between the two
compactifications are exhibited.

</DOC>
<DOC>
<DOCNO> 68691 </DOCNO>
Higher Cumulants in the Cluster Expansion in QCD


  In this work an extension of the Gaussian model of the stochastic vacuum is
presented. It consists of including higher cumulants than just the second one
in the cluster expansion in QCD. The influence of nonabelian fourth cumulants
on the potential of a static quark-antiquarkpair is examined and the formation
of flux tubes between a static $q\bar{q}$-pair is investigated. It is found
that the fourth cumulants can contribute to chromomagnetic flux tubes.
Furthermore the contribution of fourth cumulants to the total cross section of
soft high energy hadron-hadron scattering is examined and it is found that the
fourth cumulants do not change the general picture obtained in the Gaussian
model.

</DOC>
<DOC>
<DOCNO> 68368 </DOCNO>
Random Matrix Theory and Chiral Symmetry in QCD


  Random matrix theory is a powerful way to describe universal correlations of
eigenvalues of complex systems. It also may serve as a schematic model for
disorder in quantum systems. In this review, we discuss both types of
applications of chiral random matrix theory to the QCD partition function. We
show that constraints imposed by chiral symmetry and its spontaneous breaking
determine the structure of low-energy effective partition functions for the
Dirac spectrum. We thus derive exact results for the low-lying eigenvalues of
the QCD Dirac operator. We argue that the statistical properties of these
eigenvalues are universal and can be described by a random matrix theory with
the global symmetries of the QCD partition function. The total number of such
eigenvalues increases with the square root of the Euclidean four-volume. The
spectral density for larger eigenvalues (but still well below a typical
hadronic mass scale) also follows from the same low-energy effective partition
function. The validity of the random matrix approach has been confirmed by many
lattice QCD simulations in a wide parameter range. Stimulated by the success of
the chiral random matrix theory in the description of universal properties of
the Dirac eigenvalues, the random matrix model is extended to nonzero
temperature and chemical potential. In this way we obtain qualitative results
for the QCD phase diagram and the spectrum of the QCD Dirac operator. We
discuss the nature of the quenched approximation and analyze quenched Dirac
spectra at nonzero baryon density in terms of an effective partition function.
Relations with other fields are also discussed.

</DOC>
<DOC>
<DOCNO> 120975 </DOCNO>
The SPIFFI image slicer: Revival of image slicing with plane mirrors


  SPIFFI (SPectrometer for Infrared Faint Field Imaging) is the integral field
spectrograph of the VLT-instrument SINFONI (SINgle Far Object Near-infrared
Investigation). SINFONI is the combination of SPIFFI with the ESO adaptive
optics system MACAO (Multiple Application Concept for Adaptive Optics) offering
for the first time adaptive optics assisted near infrared integral field
spectroscopy at an 8m-telescope. SPIFFI works in the wavelength ranger from 1.1
to 2.5 micron with a spectral resolving power ranging from R=2000 to 4500.
Pixel scale ranges from 0.25 to 0.025 seconds of arc. The SPIFFI field-of-view
consists of 32x32 pixels which are rearranged with an image slicer to a form a
long slit. Based on the 3D slicer concept with plane mirrors, an enhanced image
slicer was developed. The SPIFFI image slicer consists of two sets of mirrors,
called the 'small' and the 'large' slicer. The small slicer cuts a square field
of view into 32 slitlets, each of which is 32 pixels long. The large slicer
rearranges the 32 slitlets into a 1024 pixels long slit. The modifications to
the 3D slicer concept affect the angles of the plane mirrors of small and large
slicer and lead to an improved slit geometry with very little light losses. At
a mirror width of 0.3mm the light loss is <5%. All reflective surfaces are flat
and can be manufactured with a high surface quality. This is especially
important for the adaptive optics mode of SINFONI. We explain the concept of
the SPIFFI mirror slicer and describe details of the manufacturing process.

</DOC>
<DOC>
<DOCNO> 101548 </DOCNO>
Cubic identities for theta series in three variables


  We introduce three-variable analogues of the theta series of Borwein and
Borwein. We prove various identities involving these theta series including a
generalization of the cubic identity of Borwein and Borwein.

</DOC>
<DOC>
<DOCNO> 178813 </DOCNO>
Semiempirical Shell Model Masses with Magic Proton Number Z=126 for


  A highly extrapolatable semiempirical shell model mass equation applicable to
translead elements up to Z=126 is presented. The equation is applied to the
recently discovered superheavy nuclei with Z=118 and A=293 and with Z=114 and
A=289 and their decay products.

</DOC>
<DOC>
<DOCNO> 84884 </DOCNO>
On the convergence of Regge calculus to general relativity


  Motivated by a recent study casting doubt on the correspondence between Regge
calculus and general relativity in the continuum limit, we explore a mechanism
by which the simplicial solutions can converge whilst the residual of the Regge
equations evaluated on the continuum solutions does not. By directly
constructing simplicial solutions for the Kasner cosmology we show that the
oscillatory behaviour of the discrepancy between the Einstein and Regge
solutions reconciles the apparent conflict between the results of Brewin and
those of previous studies. We conclude that solutions of Regge calculus are, in
general, expected to be second order accurate approximations to the
corresponding continuum solutions.

</DOC>
<DOC>
<DOCNO> 11369 </DOCNO>
Instabilities in Granular Flow


  We consider the stability of a system of equations which are a singular
perturbation of the incompressible rigid-plastic flow equations used to model
granular flow. A linear stability analysis shows that solutions of these
equations are unstable, in general, and that these instabilities may lead to
ill-posedness. However, the analysis suggests that these equations are more
regular, in a certain sense, than the unperturbed incompressible rigid-plastic
flow equations. Numerical solutions are presented which illustrate the growth
of instabilities and the development of shear-bands in the flows.

</DOC>
<DOC>
<DOCNO> 170792 </DOCNO>
Contextual objectivity : a realistic interpretation of quantum mechanics


  An attempt is made to formulate quantum mechanics (QM) in physical rather
than in mathematical terms. It is argued that the appropriate conceptual
framework for QM is "contextual objectivity", which includes an objective
definition of the quantum state. This point of view sheds new light on topics
such as the reduction postulate and the quantum measurement process.

</DOC>
<DOC>
<DOCNO> 68856 </DOCNO>
Angular Distributions in Higgs Decays


  A new theory yields unconventional results for the angular distribution of
products like $b-\bar{b}$ jets in Higgs decays.

</DOC>
<DOC>
<DOCNO> 85070 </DOCNO>
Simple excision of a black hole in 3+1 numerical relativity


  We describe a simple implementation of black hole excision in 3+1 numerical
relativity. We apply this technique to a Schwarzschild black hole with octant
symmetry in Eddington-Finkelstein coordinates and show how one can obtain
accurate, long-term stable numerical evolutions.

</DOC>
<DOC>
<DOCNO> 99517 </DOCNO>
Generalized Riemann - Liouville fractional derivatives for multifractal


  The Riemann-Liouville fractional integrals and derivatives are generalized
for cases when fractional exponent $d$ are functions of space and times
coordinates (i.e. $d=d({\bf r}(t),t)$).

</DOC>
<DOC>
<DOCNO> 40629 </DOCNO>
Observation of Tau Neutrino Interactions


  The DONUT experiment has analyzed 203 neutrino interactions recorded in
nuclear emulsion targets. A decay search has found evidence of four tau
neutrino interactions with an estimated background of 0.34 events. This number
is consistent with the Standard Model expectation.

</DOC>
<DOC>
<DOCNO> 101126 </DOCNO>
Computations of Nambu-Poisson cohomologies


  We try to generalize the Poisson cohomology of a 2-dimensional Poisson
manifold to the n-vectors on a n-dimensional manifold. We define several
cohomologies and we compute locally some of them, in the case of germs at 0 of
n-vectors on a real or complex vector field of dimension n.

</DOC>
<DOC>
<DOCNO> 117021 </DOCNO>
Emergence of Bulk CsCl Structure in (CsCl)nCs+ Cluster Ions


  The emergence of CsCl bulk structure in (CsCl)nCs+ cluster ions is
investigated using a mixed quantum-mechanical/semiempirical theoretical
approach. We find that rhombic dodecahedral fragments (with bulk CsCl symmetry)
are more stable than rock-salt fragments after the completion of the fifth
rhombic dodecahedral atomic shell. From this size (n=184) on, a new set of
magic numbers should appear in the experimental mass spectra. We also propose
another experimental test for this transition, which explicitely involves the
electronic structure of the cluster. Finally, we perform more detailed
calculations in the size range n=31--33, where recent experimental
investigations have found indications of the presence of rhombic dodecahedral
(CsCl)32Cs+ isomers in the cluster beams.

</DOC>
<DOC>
<DOCNO> 69672 </DOCNO>
Towards a Theory of Hadronic B Decays


  We review recent advances in the theory of strong-interaction effects and
final-state interactions in hadronic weak decays of heavy mesons. In the
heavy-quark limit, the amplitudes for most nonleptonic, two-body B decays can
be calculated from first principles and expressed in terms of semileptonic form
factors and light-cone distribution amplitudes. We discuss the features of this
novel QCD factorization and illustrate its phenomenological implications.

</DOC>
<DOC>
<DOCNO> 169667 </DOCNO>
Information - the Fundamental Notion of Quantum Theory


  In this article a notion of information is presented which stresses the
contextuality of quantum objects and their measurement. Mathematically this is
reached by a quantification of the quantum mechanical surplus knowledge which
has been introduced by Weizsacker. This new formulation gives insight into
relation between single quantum objects and ensembles of quantum objects. The
goal is to provide an explanatory concept for teaching purposes, the
description of quantum processes and measurement with aid of information.

</DOC>
<DOC>
<DOCNO> 100534 </DOCNO>
Perverse coherent sheaves (after Deligne)


  This note is mostly an exposition of an unpublished result of Deligne, which
introduces an analogue of perverse $t$-structure on the derived category of
coherent sheaves on a Noetherian scheme with a dualizing complex. Construction
extends to the category of coherent sheaves equivariant under an action of an
algebraic group; though proof of the general statement in this case does not
require new ideas, it provides examples (such as sheaves on the nilpotent cone
of a semi-simple group equivariant under the adjoint action) where construction
of coherent ``intersection cohomology'' sheaves works.

</DOC>
<DOC>
<DOCNO> 119341 </DOCNO>
On neutron star/supernova remnant associations


  It is pointed out that a cavity supernova (SN) explosion of a moving massive
star could result in a significant offset of the neutron star (NS) birth-place
from the geometrical centre of the supernova remnant (SNR). Therefore: a) the
high implied transverse velocities of a number of NSs (e.g. PSR B1610-50, PSR
B1757-24, SGR0525-66) could be reduced; b) the proper motion vector of a NS
should not necessarily point away from the geometrical centre of the associated
SNR; c) the circle of possible NS/SNR associations could be enlarged. An
observational test is discussed, which could allow to find the true
birth-places of NSs associated with middle-aged SNRs, and thereby to get more
reliable estimates of their transverse velocities.

</DOC>
<DOC>
<DOCNO> 116996 </DOCNO>
Impedance of a Beam Tube with Small Corrugations


  In accelerator projects involving the use of very short bunches, such as the
Linac Coherent Light Source (LCLS)-where the rms bunch length in the undulator
section is 30 micron-, it appears that even submicron imperfections in the beam
tube surface can generate an impedance that is unacceptably large. We consider
two periodic models of an imperfect, rough surface, one with small rectangular
corrugations, the other with smooth sinusoidal oscillations. We compare the
impedance of these two models.

</DOC>
<DOC>
<DOCNO> 84351 </DOCNO>
On the Particle Definition in the presence of Black Holes


  A canonical particle definition via the diagonalisation of the Hamiltonian
for a quantum field theory in specific curved space-times is presented. Within
the provided approach radial ingoing or outgoing Minkowski particles do not
exist. An application of this formalism to the Rindler metric recovers the
well-known Unruh effect. For the situation of a black hole the Hamiltonian
splits up into two independent parts accounting for the interior and the
exterior domain, respectively. It turns out that a reasonable particle
definition may be accomplished for the outside region only. The Hamiltonian of
the field inside the black hole is unbounded from above and below and hence
possesses no ground state. The corresponding equation of motion displays a
linear global instability. Possible consequences of this instability are
discussed and its relations to the sonic analogues of black holes are
addressed. PACS-numbers: 04.70.Dy, 04.62.+v, 10.10.Ef, 03.65.Db.

</DOC>
<DOC>
<DOCNO> 85186 </DOCNO>
Berry phase for spin--1/2 particles moving in a spacetime with torsion


  Berry phase for a spin--1/2 particle moving in a flat spacetime with torsion
is investigated in the context of the Einstein-Cartan-Dirac model. It is shown
that if the torsion is due to a dense polarized background, then there is a
Berry phase only if the fermion is massless and its momentum is perpendicular
to the direction of the background polarization. The order of magnitude of this
Berry phase is discussed in other theoretical frameworks.

</DOC>
<DOC>
<DOCNO> 101477 </DOCNO>
Summation Formulas for the product of the q-Kummer Functions from


  Using the representation of E_q(2) on the non-commutative space
zz^*-qz^*z=\sigma; q<1, \sigma>0 summation formulas for the product of two,
three and four q-Kummer functions are derived.

</DOC>
<DOC>
<DOCNO> 39693 </DOCNO>
Search for the Decay $K_L \to \pi^0 \mu^+ \mu^-$


  We report on a search for the decay \klpimumu carried out as a part of the
KTeV experiment at Fermilab. This decay is expected to have a significant $CP$
violating contribution and a direct measurement will either support the CKM
mechanism for CP violation or point to new physics. Two events were observed in
the 1997 data with an expected background of $0.87 \pm 0.15$ events, and we set
an upper limit \BR{\klpimumu} $ <3.8 \times 10^{-10}$ at the 90% confidence
level.

</DOC>
<DOC>
<DOCNO> 11542 </DOCNO>
Creep motion in a granular pile exhibiting steady surface flow


  We investigate experimentally granular piles exhibiting steady surface flow.
Below the surface flow, it has been believed exisitence of a `frozen' bulk
region, but our results show absence of such a frozen bulk. We report here that
even the particles in deep layers in the bulk exhibit very slow flow and that
such motion can be detected at an arbitrary depth. The mean velocity of the
creep motion decays exponentially with depth, and the characteristic decay
length is approximately equal to the particle-size and independent of the flow
rate. It is expected that the creep motion we have seeen is observable in all
sheared granular systems.

</DOC>
<DOC>
<DOCNO> 116876 </DOCNO>
On the Confidence Interval for the parameter of Poisson Distribution


  The possibility of construction of continuous analogue of Poisson
distribution with the search of bounds of confidence intervals for parameter of
Poisson distribution is discussed. Also, in the article is shown that the true
value of a parameter of Poisson distribution for the observed value $\hat x$
has Gamma distribution with the scale parameter, which is equal to one, and the
shape parameter, which is equal to $\hat x$. The results of numerical
construction of confidence intervals are presented.

</DOC>
<DOC>
<DOCNO> 152135 </DOCNO>
Quantization of The Electroweak Theory in The Hamiltonian Path-Integral


  The quantization of the SU(2)$\times $U(1) gauge-symmetric electroweak theory
is performed in the Hamiltonian path-integral formalism. In this quantization,
we start from the Lagrangian given in the unitary gauge in which the unphysical
Goldstone fields are absent, but the unphysical longitudinal components of the
gauge fields still exist. In order to eliminate the longitudinal components, it
is necessary to introduce the Lorentz gauge conditions as constraints. These
constraints may be incorporated into the Lagrangian by the Lagrange
undetermined multiplier method. In this way, it is found that every component
of a four-dimensional vector potential has a conjugate counterpart. Thus, a
Lorentz-covariant quantization in the Hamiltonian path-integral formalism can
be well accomplished and leads to a result which is the same as given by the
Faddeev-Popov approach of quantization.

</DOC>
<DOC>
<DOCNO> 121024 </DOCNO>
SCUBA observations of Hawaii 167


  We present the first submillimetre observations of the z=2.36 broad
absorption line system Hawaii 167. Our observations confirm the hypothesis that
Hawaii 167 contains a massive quantity of dust, the optical depth of which is
sufficient to completely extinguish our ultraviolet view of a central, buried
quasar. Hawaii~167's submillimetre luminosity and associated dust mass are
similar to the ultraluminous class of infrared galaxies, supporting the
existence of an evolutionary link between these and the active galaxy
population. Hawaii 167 appears to be a young quasar which is emerging from its
dusty cocoon.

</DOC>
<DOC>
<DOCNO> 72003 </DOCNO>
Polarized Proton Nucleus Scattering


  We show that, to a very good approximation, the ratio of the spin-flip to the
non-flip parts of the elastic proton-nucleus amplitude is the same as for
proton-nucleon scattering at very high energy. The result is used to do a
realistic calculation of the analyzing power A_N for pC scattering in the
Coulomb-nuclear interference (CNI) region of momentum transfer.

</DOC>
<DOC>
<DOCNO> 120481 </DOCNO>
Resolving the 10-40 keV Cosmic X-ray Background with Constellation-X


  The energy density of the Cosmic X-ray background (XRB) peaks around 30 keV
(see Figure 1), an energy not yet probed by focussing imaging instruments. The
first hard X-ray telescope due to fly on a space mission will be that on board
Constellation-X. The imaging capability, besides providing an improvement of
several orders of magnitude in sensitivity over current passively collimated
detectors, will permit for the first time to resolve a fraction of the XRB at
this most crucial energy. Synthesis models of the XRB based on obscured AGN
predict that at least 40% of the 10-40 keV XRB will be resolved by
Constellation-X.

</DOC>
<DOC>
<DOCNO> 9034 </DOCNO>
Monte Carlo simulation of nonlinear Couette flow in a dilute gas


  The Direct Simulation Monte Carlo method is applied to solve the Boltzmann
equation in the steady planar Couette flow for Maxwell molecules and hard
spheres. Nonequilibrium boundary conditions based on the solution of the
Bhatnagar-Gross-Krook (BGK) model for the Couette flow are employed to diminish
the influence of finite-size effects. Non-Newtonian properties are
characterized by five independent generalized transport coefficients: a
viscosity function, a thermal conductivity function, two viscometric functions,
and a cross coefficient measuring the heat flux orthogonal to the thermal
gradient. These coefficients depend nonlinearly on the shear rate. The
simulation results are compared with theoretical predictions given by the Grad
method and the BGK and the ellipsoidal statistical (ES) models. It is found
that the kinetic models present a good agreement with the simulation,
especially in the case of the ES model, while the Grad method is only
qualitatively reliable for the momentum transport. In addition, the velocity
distribution function is also measured and compared with the BGK and ES
distributions.

</DOC>
<DOC>
<DOCNO> 101318 </DOCNO>
Tableau atoms and a new Macdonald positivity conjecture


  Let $\Lambda$ be the space of symmetric functions and $V_k$ be the subspace
spanned by the modified Schur functions $\{S_\lambda[X/(1-t)]\}_{\lambda_1\leq
k}$. We introduce a new family of symmetric polynomials,
$\{A_{\lambda}^{(k)}[X;t]\}_{\lambda_1\leq k}$, constructed from sums of
tableaux using the charge statistic. We conjecture that the polynomials
$A_{\lambda}^{(k)}[X;t]$ form a basis for $V_k$ and that the Macdonald
polynomials indexed by partitions whose first part is not larger than $k$
expand positively in terms of our polynomials. A proof of this conjecture would
not only imply the Macdonald positivity conjecture, but would substantially
refine it. Our construction of the $A_\lambda^{(k)}[X;t]$ relies on the use of
tableaux combinatorics and yields various properties and conjectures on the
nature of these polynomials. Another important development following from our
investigation is that the $A_{\lambda}^{(k)}[X;t]$ seem to play the same role
for $V_k$ as the Schur functions do for $\Lambda$. In particular, this has led
us to the discovery of many generalizations of properties held by the Schur
functions, such as Pieri and Littlewood-Richardson type coefficients.

</DOC>
<DOC>
<DOCNO> 117247 </DOCNO>
Why We Can Not Walk To and Fro in Time as Do it in Space? (Why the Arrow


  Existence of arrow of time in our world may be easy explained if time has
multifractal nature. The interpretation of nature of time arrow is made on the
base of multifractal theory of time and space presented at works
\cite{kob1}-\cite{kob15}. In this paper shown possibility to walk to and fro in
space and necessity of huge amount of energy for stopping time and changing
direction of it in microscopic volumes. 
  Contents: 1. Introduction 2.Universe as Time and Space with Fractional
Dimensions 3. Why Time has Direction Only to Future and Why Impossible to Walk
in Time To and Fro? 4. Is It Possible to Change Direction of Time and How Much
Energy It Needs? 5.How Much Energy Needs for Stopping Time and Moving it Back
in the Volume of Cubic Centimeter During One Second? 6. Why We Can Walk To and
Fro in Our Space? 7. Conclusions

</DOC>
<DOC>
<DOCNO> 85136 </DOCNO>
The warp drive: hyper-fast travel within general relativity


  It is shown how, within the framework of general relativity and without the
introduction of wormholes, it is possible to modify a spacetime in a way that
allows a spaceship to travel with an arbitrarily large speed. By a purely local
expansion of spacetime behind the spaceship and an opposite contraction in
front of it, motion faster than the speed of light as seen by observers outside
the disturbed region is possible. The resulting distortion is reminiscent of
the ``warp drive'' of science fiction. However, just as it happens with
wormholes, exotic matter will be needed in order to generate a distortion of
spacetime like the one discussed here.

</DOC>
<DOC>
<DOCNO> 84428 </DOCNO>
Open cosmologies with rotation


  We study a rotating and expanding, Godel type metric, originally considered
by Korotkii and Obukhov, showing that, in the limit of large times and nearby
distances, it reduces to the open metric of Friedmann. In the epochs when
radiation or dust matter dominate the energy density, our solutions are similar
to the isotropic ones and, in what concerns processes occurring at small times,
the rotation leads only to higher order corrections. At large times, the
solution is dominated by a decaying positive cosmological term, with negative
pressure, and necessarily describes a quasi-flat universe if the energy
conditions have to be satisfied. The absence of closed time-like curves
requires a superior limit for the global angular velocity, which appears as a
natural explanation for the observed smallness of the present rotation. The
conclusion is that the introduction of a global rotation, in addition to be
compatible with observation, can enrich the standard model of the Universe,
explaining issues like the origin of galaxies rotation and the quasi-flatness
problem.

</DOC>
<DOC>
<DOCNO> 11571 </DOCNO>
Angular Structure of Lacunarity, and the Renormalisation Group


  We formulate the angular structure of Lacunarity in fractals, in terms of a
symmetry reduction of the three point correlation function. This provides a
rich probe of universality, and first measurements yield new evidence in
support of the equivalence between self-avoiding walks and percolation
perimeters in two dimensions.
  We argue the Lacunarity reveals much of the Renormalisation Group in real
space. This is supported by exact calculations for Random Walks and measured
data for percolation clusters and SAW's. Relationships follow between exponents
governing inwards and outwards propagating perturbations, and we also find a
very general test for the contribution of long range interactions.

</DOC>
<DOC>
<DOCNO> 13399 </DOCNO>
Supersymmetry and d-Wave Superconductivity


  Motivated by a recent development in the field theory of the fractional
quantum Hall effect, we propose a supersymmetric field theoretical model of
quantum critical d-wave and (d+id)-wave superconductors. New concept is a
composite particle with the supercharge which is formed by electron (hole) and
supersymmetric collective configurations of spin and charge. Quantum critical
d-wave superconductor is characterized as the condensate of these composite
particles.

</DOC>
<DOC>
<DOCNO> 117839 </DOCNO>
The Evolution of He4 and LiBeB


  Our understanding of the evolution of He4 and Li7 depends critically on the
available data for these two elements at low metallicity. In particular, the
degree to which there is a slope in an abundance vs metallicity regression can
help determine the evolution of He, C, N, and O in dwarf galaxies in the case
of He, and cosmic-ray induced nucleosynthesis of LiBeB in our own galaxy in the
case of Li. Recent data and their implications will be discussed.

</DOC>
<DOC>
<DOCNO> 169606 </DOCNO>
Qudit Entanglement


  We consider the separability of various joint states of D-dimensional quantum
systems, which we call "qudits." We derive two main results: (i) the
separability condition for a two-qudit state that is a mixture of the maximally
mixed state and a maximally entangled state; (ii) lower and upper bounds on the
size of the neighorhood of separable states surrounding the maximally mixed
state for N qudits.

</DOC>
<DOC>
<DOCNO> 151248 </DOCNO>
Hidden Superconformal Symmetry in M Theory


  The bosonic sectors of the eleven dimensional and IIA supergravity theories
are derived as non-linear realisations. The underlying group includes the
conformal group, the general linear group and as well as automorphisms of the
supersymmetry algebra. We discuss the supersymmetric extension and argue that
Osp(1/64) is a symmetry of M theory. We also derive the effective action of the
closed bosonic string as a non-linear realisation.

</DOC>
<DOC>
<DOCNO> 85354 </DOCNO>
Noise Kernel in Stochastic Gravity and Stress Energy Bi-Tensor of


  The noise kernel is the vacuum expectation value of the (operator-valued)
stress-energy bi-tensor which describes the fluctuations of a quantum field in
curved spacetimes. It plays the role in stochastic semiclassical gravity based
on the Einstein-Langevin equation similar to the expectation value of the
stress-energy tensor in semiclassical gravity based on the semiclassical
Einstein equation. According to the stochastic gravity program, this two point
function (and by extension the higher order correlations in a hierarchy) of the
stress energy tensor possesses precious statistical mechanical information of
quantum fields in curved spacetime and, by the self-consistency required of
Einstein's equation, provides a probe into the coherence properties of the
gravity sector (as measured by the higher order correlation functions of
gravitons) and the quantum nature of spacetime. It reflects the low and medium
energy (referring to Planck energy as high energy) behavior of any viable
theory of quantum gravity, including string theory. It is also useful for
calculating quantum fluctuations of fields in modern theories of structure
formation and for backreaction problems in cosmological and black holes
spacetimes.
 We discuss the properties of this bi-tensor with the method of
point-separation, and derive a regularized expression of the noise-kernel for a
scalar field in general curved spacetimes. One collorary of our finding is that
for a massless conformal field the trace of the noise kernel identically
vanishes. We outline how the general framework and results derived here can be
used for the calculation of noise kernels for Robertson-Walker and
Schwarzschild spacetimes.

</DOC>
<DOC>
<DOCNO> 102141 </DOCNO>
Comparison of algorithms to calculate quadratic irregularity of prime


  In previous work, the author has extended the concept of regular and
irregular primes to the setting of arbitrary totally real number fields k_{0},
using the values of the zeta function \zeta_{k_{0}} at negative integers as our
``higher Bernoulli numbers''. In the case where k_{0} is a real quadratic
field, Siegel presented two formulas for calculating these zeta-values: one
using entirely elementary methods and one which is derived from the theory of
modular forms. (The author would like to thank Henri Cohen for suggesting an
analysis of the second formula.) We briefly discuss several algorithms based on
these formulas and compare the running time involved in using them to determine
the index of k_{0}-irregularity (more generally, ``quadratic irregularity'') of
a prime number.

</DOC>
<DOC>
<DOCNO> 69508 </DOCNO>
R-symmetry, Yukawa textures and anomaly mediated supersymmetry breaking


  We explore, in the MSSM context, an extension of the Anomaly Mediated
Supersymmetry Breaking solution for the soft scalar masses that is possible if
the underlying theory has a gauged R-symmetry. The slepton mass problem
characteristic of the scenario is resolved, and a context for the explanation
of the fermion mass hierarchy provided.

</DOC>
<DOC>
<DOCNO> 169761 </DOCNO>
Fermi gas in harmonic oscillator potentials


  Assuming the validity of grand canonical statistics, we study the properties
of a spin-polarized Fermi gas in harmonic traps. Universal forms of Fermi
temperature $T_F$, internal energy $U$ and the specific heat per particle of
the trapped Fermi gas are calculated as a {\it function} of particle number,
and the results compared with those of infinite number particles.

</DOC>
<DOC>
<DOCNO> 122189 </DOCNO>
The Structure of Self-Gravitating Polytropic Systems with n around 5


  We investigate the structure of self-gravitating polytropic stellar systems.
We present a method which allows to obtain approximate analytical solutions,
$\psi_{n+\epsilon}({\bf x})$, of the nonlinear Poisson equation with the
polytropic index $n+\epsilon$, given the solution $\psi_n({\bf x})$ with the
polytropic index n, for any positive or negative $\epsilon$ such that
$|\epsilon|\ll1$. Application of this method to the spherically symmetric
stellar polytropes with $n\simeq5$ yields the solutions which describe
spatially bound systems if n<5 and the formation of a second core if n>5. A
heuristic approximate expressions for the radial profiles are also presented.
Due to the duality between stellar and gas polytropes, our results are valid
for gaseous, self-gravitating polytropic systems (e.g., molecular clouds) with
the index $\gamma\simeq 6/5$. Stability of such systems and observational
consequences for both stellar and gaseous systems are discussed.

</DOC>
<DOC>
<DOCNO> 84604 </DOCNO>
A Classification of Spherically Symmetric Static Solutions of SU(2)


  We categorize the global structure of spherically symmetric static solutions
of Einstein SU(2) Yang Mills equations with positive cosmological constant that
are smooth at the center of spherical symmetry.

</DOC>
<DOC>
<DOCNO> 10406 </DOCNO>
Probing Bose-Einstein Condensation of Excitons with Electromagnetic


  We examine the absorption spectrum of electromagnetic radiation from
excitons, where an exciton in the $1s$ state absorbs a photon and makes a
transition to the $2p$ state. We demonstrate that the absorption spectrum
depends strongly on the quantum degeneracy of the exciton gas, and that it will
generally manifest many-body effects. Based on our results we propose that
absorption of infrared radiation could resolve recent contradictory
experimental results on excitons in Cu$_2$O.

</DOC>
<DOC>
<DOCNO> 170089 </DOCNO>
Separability and distillability in composite quantum systems -a primer-


  Quantum mechanics is already 100 years old, but remains alive and full of
challenging open problems. On one hand, the problems encountered at the
frontiers of modern theoretical physics like Quantum Gravity, String Theories,
etc. concern Quantum Theory, and are at the same time related to open problems
of modern mathematics. But even within non-relativistic quantum mechanics
itself there are fundamental unresolved problems that can be formulated in
elementary terms. These problems are also related to challenging open questions
of modern mathematics; linear algebra and functional analysis in particular.
Two of these problems will be discussed in this article: a) the separability
problem, i.e. the question when the state of a composite quantum system does
not contain any quantum correlations or entanglement and b) the distillability
problem, i.e. the question when the state of a composite quantum system can be
transformed to an entangled pure state using local operations (local refers
here to component subsystems of a given system).
  Although many results concerning the above mentioned problems have been
obtained (in particular in the last few years in the framework of Quantum
Information Theory), both problems remain until now essentially open. We will
present a primer on the current state of knowledge concerning these problems,
and discuss the relation of these problems to one of the most challenging
questions of linear algebra: the classification and characterization of
positive operator maps.

</DOC>
<DOC>
<DOCNO> 8216 </DOCNO>
Imaging Inter-Edge State Scattering Centers in the Quantum Hall Regime


  We use an atomic force microscope tip as a local gate to study the scattering
between edge channels in a 2D electron gas in the quantum Hall regime. The
scattering is dominated by individual, microscopic scattering centers, which we
directly image here for the first time. The tip voltage dependence of the
scattering indicates that tunneling occurs through weak links and localized
states.

</DOC>
<DOC>
<DOCNO> 68864 </DOCNO>
$\mu \to e \gamma$ and $\mu \to 3e$ Processes with Polarized Muon and


  Lepton flavor violating processes $\mu \to e \gamma$ and $\mu \to 3e$ with
polarized muons are studied in the supersymmetric grand unified theory (SUSY
GUT). As a result of a detailed numerical calculation, it is shown that the P-
and T-odd asymmetries defined with the help of the muon polarization and the
ratio of two branching fractions make a good contrast between the SU(5) and
SO(10) SUSY GUT. These observables are useful to extract differences of the two
theories. In particular, the P-odd asymmetry of $\mu \to e \gamma$ varies
100%--100% in SO(10) whereas it is 100% in SU(5) and the T-odd asymmetry of
$\mu \to 3e$ can reach 15% in SU(5) within the EDM constraints whereas it is
small in SO(10).

</DOC>
<DOC>
<DOCNO> 69714 </DOCNO>
Radiative corrections to Zb{\bar b} production


  We report on QCD radiative corrections to the process, p\bar{p} to Zb\bar{b}
in the approximation in which the b-quark is considered massless. The
implementation of this process in the general purpose Monte Carlo program MCFM
is discussed in some detail. These results are used to investigate backgrounds
to Higgs boson production in the ZH channel. We investigate the Higgs mass
range (100 GeV < m_H < 130 GeV) for the Tevatron running at sqrt{s}=2 TeV.

</DOC>
<DOC>
<DOCNO> 12828 </DOCNO>
Critical behavior of the three-dimensional XY universality class


  We improve the theoretical estimates of the critical exponents for the
three-dimensional XY universality class. We find alpha=-0.0146(8),
gamma=1.3177(5), nu=0.67155(27), eta=0.0380(4), beta=0.3485(2), and
delta=4.780(2). We observe a discrepancy with the most recent experimental
estimate of alpha; this discrepancy calls for further theoretical and
experimental investigations. Our results are obtained by combining Monte Carlo
simulations based on finite-size scaling methods, and high-temperature
expansions. Two improved models (with suppressed leading scaling corrections)
are selected by Monte Carlo computation. The critical exponents are computed
from high-temperature expansions specialized to these improved models. By the
same technique we determine the coefficients of the small-magnetization
expansion of the equation of state. This expansion is extended analytically by
means of approximate parametric representations, obtaining the equation of
state in the whole critical region. We also determine the specific-heat
amplitude ratio.

</DOC>
<DOC>
<DOCNO> 99644 </DOCNO>
A W(E_6)-equivariant projective embedding of the moduli space of cubic


  An explicit projective embedding of the moduli space of marked cubic surfaces
is given. This embedding is equivariant under the Weyl group of type E6. The
image is defined by a system of linear and cubic equations. To express the
embedding in a most symmetric way, the target would be 79-dimensional, however
the image lies in a 9-dimensional linear subspace.

</DOC>
<DOC>
<DOCNO> 40463 </DOCNO>
Goldstone boson-nucleon dynamics: Working group summary and outlook


  We highlight some of the recent results in chiral dynamics for systems with
one nucleon/baryon presented at Chiral Dynamics 2000. We outline the most
urgent experimental and theoretical challenges to be tackled in the coming
years.

</DOC>
<DOC>
<DOCNO> 117670 </DOCNO>
Modeling the Photoionized Interface in Blister HII Regions


  We present a grid of photoionization models for the emission from
photoevaporative interfaces between the ionized gas and molecular cloud in
blister HII regions. For the density profiles of the emitting gas in the
models, we use a general power law form calculated for photoionized,
photoevaporative flows by Bertoldi (1989). We find that the spatial emission
line profiles are dependent on the incident flux, the shape of the ionizing
continuum and the elemental abundances. In particular, we find that the peak
emissivity of the [SII] and [NII] lines are more sensitive to the elemental
abundances than are the total line intensities. The diagnostics obtained from
the grid of models can be used in conjunction with high spatial resolution data
to infer the properties of ionized interfaces in blister HII regions. As an
example, we consider a location at the tip of an ``elephant trunk'' structure
in M16 (the Eagle Nebula) and show how narrow band HST-WFPC2 images constrain
the HII region properties. We present a photoionization model that explains the
ionization structure and emission from the interface seen in these high spatial
resolution data.

</DOC>
<DOC>
<DOCNO> 72138 </DOCNO>
The $\eta^\prime g^* g^*$ vertex with arbitrary gluon virtualities in


  We study the $\eta^\prime g^* g^*$ vertex for arbitrary gluon virtualities in
the time-like and space-like regions, using the perturbative QCD hard
scattering approach and an input wave-function of the $\eta^\prime$-meson
consistent with the measured $\eta^\prime \gamma^* \gamma$ transition form
factor. The contribution of the gluonic content of the $\eta^\prime$-meson is
taken into account, enhancing the form factor over the entire virtuality
considered. However, data on the electromagnetic transition form factor of the
$\eta^\prime$-meson is not sufficient to quantify the gluonic enhancement. We
also study the effect of the transverse momenta of the partons in the
$\eta^\prime$-meson on the $\eta^\prime g^* g^*$ vertex, using the modified
hard scattering approach based on Sudakov formalism. Analytic expressions for
the $\eta^\prime g^* g^*$ vertex are presented in limiting kinematic regions
and parametrizations are given satisfying the QCD anomaly, for real gluons, and
perturbative QCD behavior for large gluon virtualities, in both the time-like
and space-like regions. Our results have implications for the inclusive decay
$B \to \eta^\prime X$ and exclusive decays, such as $B \to \eta^\prime
(K,K^*)$, and in hadronic production processes $N + N (\bar N) \to \eta^\prime
X$.

</DOC>
<DOC>
<DOCNO> 8743 </DOCNO>
An Introduction to Quantum Algebras and Their Applications


  A very elementary introduction to quantum algebras is presented and a few
examples of their physical applications are mentioned.

</DOC>
<DOC>
<DOCNO> 120579 </DOCNO>
Multiwavelength observations of clusters of galaxies and the role of


  Some clusters of galaxies have been identified as powerful sources of
non-thermal radiation, from the radio to X-ray wavelengths. The classical
models proposed for the explanation of this radiation usually require large
energy densities in cosmic rays in the intracluster medium and magnetic fields
much lower that those measured using the Faraday rotation. We study here the
role that mergers of clusters of galaxies may play in the generation of the
non-thermal radiation, and we seek for additional observable consequences of
the model. We find that if hard X-rays and radio radiation are respectively
interpreted as inverse Compton scattering (ICS) and synchrotron emission of
relativistic electrons, large gamma ray fluxes are produced, and for the Coma
cluster, where upper limits are available, these limits are exceeded. We also
discuss an alternative and testable model that naturally solves the problems
mentioned above.

</DOC>
<DOC>
<DOCNO> 118257 </DOCNO>
Statistical properties of SGR 1806-20 bursts


  We present statistics of SGR 1806-20 bursts, combining 290 events detected
with RXTE/PCA, 111 events detected with BATSE and 134 events detected with ICE.
We find that the fluence distribution of bursts observed with each instrument
are well described by power laws with indices 1.43, 1.76 and 1.67,
respectively. The distribution of time intervals between successive bursts from
SGR 1806-20 is described by a lognormal function with a peak at 103 s. There is
no correlation between the burst intensity and either the waiting times till
the next burst or the time elapsed since the previous burst. In all these
statistical properties, SGR 1806-20 bursts resemble a self-organized critical
system, similar to earthquakes and solar flares. Our results thus support the
hypothesis that the energy source for SGR bursts is crustquakes due to the
evolving, strong magnetic field of the neutron star, rather than any accretion
or nuclear power.

</DOC>
<DOC>
<DOCNO> 71255 </DOCNO>
The role of final state interactions in epsilon'/epsilon


  The Standard Model prediction for epsilon'/epsilon is updated, taking into
account the chiral loop corrections induced by final state interactions. The
resulting value, epsilon'/epsilon = (17\pm 6)\times 10^{-4}, is in good
agreement with present measurements.

</DOC>
<DOC>
<DOCNO> 83255 </DOCNO>
Boosting the Differences: A fast Bayesian classifier neural network


  A Bayesian classifier that up-weights the differences in the attribute values
is discussed. Using four popular datasets from the UCI repository, some
interesting features of the network are illustrated. The network is suitable
for classification problems.

</DOC>
<DOC>
<DOCNO> 121691 </DOCNO>
Object Classification in Astronomical Multi-Color Surveys


  We present a photometric method for identifying stars, galaxies and quasars
in multi-color surveys, which uses a library of >65000 color templates. The
method aims for extracting the information content of object colors in a
statistically correct way and performs a classification as well as a redshift
estimation for galaxies and quasars in a unified approach. For the redshift
estimation, we use an advanced version of the MEV estimator which determines
the redshift error from the redshift dependent probability density function.
  The method was originally developed for the CADIS survey, where we checked
its performance by spectroscopy. The method provides high reliability (6 errors
among 151 objects with R<24), especially for quasar selection, and redshifts
accurate within sigma ~ 0.03 for galaxies and sigma ~ 0.1 for quasars.
  We compare a few model surveys using the same telescope time but different
sets of broad-band and medium-band filters. Their performance is investigated
by Monte-Carlo simulations as well as by analytic evaluation in terms of
classification and redshift estimation. In practice, medium-band surveys show
superior performance. Finally, we discuss the relevance of color calibration
and derive important conclusions for the issues of library design and choice of
filters. The calibration accuracy poses strong constraints on an accurate
classification, and is most critical for surveys with few, broad and deeply
exposed filters, but less severe for many, narrow and less deep filters.

</DOC>
<DOC>
<DOCNO> 9440 </DOCNO>
The influence of single magnetic impurities on the conductance of


  The nonlinear ballistic conductance of three-dimensional quantum
microconstrictions, which contain magnetic impurities, is investigated. The
nonlinear part of the conductance, which is due to the interaction of electrons
with magnetic impurities is obtained. The analytical results have been analyzed
numerically. It is shown that intensity of the Kondo anomaly in the conductance
as the function of the applied voltage depends on the diameter of the
constriction and the positions of impurities.

</DOC>
<DOC>
<DOCNO> 72197 </DOCNO>
Equivalence between Gaussian averaged neutrino oscillations and neutrino


  In this paper, we show that a Gaussian averaged neutrino oscillation model is
equivalent to a neutrino decoherence model. Without loss of generality, the
analysis is performed with two neutrino flavors. We also estimate the damping
(or decoherence) parameter for atmospheric neutrinos and compare it to earlier
obtained results.

</DOC>
<DOC>
<DOCNO> 100600 </DOCNO>
On the interior structure of exterior algebra


  It is constructed the functor from category of product linear space to
category of skew-symmetric tensor space. It is defined and described the bound
bundle as analog of a symplex and as basis element of new constructive homology
theory.

</DOC>
<DOC>
<DOCNO> 122613 </DOCNO>
On the multi-periodicities in the X-ray dipper XB 1916-053


  Using the Rossi X-ray Timing Explorer and the Nordic Optical Telescope we
have obtained the highest ever quality X-ray/white-light high-speed photometry
of XB 1916-053. We refine the X-ray period (P_X) to 3000.6+/-0.2s via a
restricted cycle counting approach. Using our complete optical lightcurve, we
have extended the optical period (P_opt) ephemeris by another 4 years,
providing further evidence for its stability, although a slightly longer period
of 3027.555+/-0.002s now provides a marginally better fit. Moreover,
modulations at both P_X and P_opt are present in the optical data, with the
former dominating the nightly lightcurves (i.e. a few cycles of data). We have
also attempted to determine the ``beat'' period, as seen in the repeating
evolution of the X-ray dip structure, and the variation in primary dip phase.
We find that a quasi-period of 4.74+/-0.05d provides the best fit to the data,
even then requiring phase shifts between cycles, with the expected 3.90d
``beat'' of P_X and P_opt appearing to be less likely.
        Finally, considering the nature of each of these temporal phenomena, we
outline possible models, which could explain all of the observed behaviour of
this enigmatic source, focusing on which of P_X or P_opt is the binary period.

</DOC>
<DOC>
<DOCNO> 118839 </DOCNO>
TGRS Observations of Positron Annihilation in Classical Novae


  The TGRS experiment on board the Wind spacecraft has many advantages as a sky
monitor --- broad field of view (~2 pi) centered on the south ecliptic pole),
long life (1994-present), and stable low background and continuous coverage due
to Wind's high altitude high eccentricity orbit. The Ge detector has sufficient
energy resolution (3-4 keV at 511 keV) to resolve a cosmic positron
annihilation line from the strong background annihilation line from beta-decays
induced by cosmic ray impacts on the instrument, if the cosmic line is
Doppler-shifted by this amount. Such lines (blueshifted) are predicted from
nucleosynthesis in classical novae. We have searched the entire TGRS database
for 1995-1997 for this line, with negative results. In principle such a search
could yield an unbiased upper limit on the highly-uncertain Galactic nova rate.
We carefully examined the times around the known nova events during this
period, also with negative results. The upper limit on the nova line flux in a
6-hr interval is typically <3.8 E-3 photon/(cm2 s) at 4.6 sigma. We performed
the same analysis for times around the outburst of Nova Vel 1999, obtaining a
worse limit due to recent degradation of the detector response caused by cosmic
ray induced damage.

</DOC>
<DOC>
<DOCNO> 13095 </DOCNO>
Fast Incomplete Decoherence of Nuclear Spins in Quantum Hall Ferromagnet


  A scenario of quantum computing process based on the manipulation of a large
number of nuclear spins in Quantum Hall (QH) ferromagnet is presented. It is
found that vacuum quantum fluctuations in the QH ferromagnetic ground state at
filling factor $\nu =1$, associated with the virtual excitations of spin waves,
lead to fast incomplete decoherence of the nuclear spins. A fundamental upper
bound on the length of the computer memory is set by this fluctuation effect.

</DOC>
<DOC>
<DOCNO> 39766 </DOCNO>
Search for antihelium in cosmic rays


  The Alpha Magnetic Spectrometer (AMS) was flown on the space shuttle
Discovery during flight STS-91 in a 51.7 degree orbit at altitudes between 320
and 390 km. A total of 2.86 * 10^6 helium nuclei were observed in the rigidity
range 1 to 140 GV. No antihelium nuclei were detected at any rigidity. An upper
limit on the flux ratio of antihelium to helium of < 1.1 * 10^-6 is obtained.

</DOC>
<DOC>
<DOCNO> 7731 </DOCNO>
Theory of magnetic order in the three-dimensional spatially anisotropic


  A spin-rotation-invariant Green's-function theory of long-range and
short-range order (SRO) in the $S=1/2$ antiferromagnetic Heisenberg model with
spatially anisotropic couplings on a simple cubic lattice is presented. The
staggered magnetization, the two-spin correlation functions, the correlation
leng spin-rotation-invariant Green's-function theory of long-range and
short-range order (SRO) in the $S=1/2$ antiferromagnetic Heisenberg model with
spatially anisotropic couplings on a simple cubic lattice is presented. The
staggered magnetization, the two-spin correlation functions, the correlation
lengths, and the static spin susceptibility are calculated self-consistently
over the whole temperature region, where the effects of spatial anisotropy are
explored. As compared with previous spin-wave approaches, the N\'{e}el
temperature is reduced by the improved description of SRO. The maximum in the
temperature dependence of the uniform static susceptibility is shifted with
anisotropy and is ascribed to the decrease of SRO with increasing temperature.
Comparing the theory with experimental data for the magnetization and
correlation length of La$_2$CuO$_4$, a good agreement in the temperature
dependences is obtained.

</DOC>
<DOC>
<DOCNO> 121352 </DOCNO>
Starbursts and the Evolution of Gas-Rich Galaxies


  Moderately luminous starbursts in the nearby universe often occur in disk
galaxies that are at most subject to mild external perturbations. An
investigation of this type of galaxy leads to a better understanding of
starburst triggering mechanisms and the resulting star formation processes, and
provides useful comparisons to more extreme starbursts seen at high redshifts.

</DOC>
<DOC>
<DOCNO> 100840 </DOCNO>
Topology of Diophantine Sets: Remarks on Mazur's Conjectures


  We show that Mazur's conjecture on the real topology of rational points on
varieties implies that there is no diophantine model of the rational integers
in the rational numbers. We also prove that there is a diophantine model of the
polynomial ring over a finite field in the ring of rational functions over that
finite field. Both proofs depend upon Matijasevich's theorem.

</DOC>
<DOC>
<DOCNO> 121680 </DOCNO>
Stability of Toomre-Hayashi Disk


  We investigate stability of Toomre-Hayashi model for a self-gravitating,
rotating gas disk. The rotation velocity, $ v_\phi $, and sound speed, $ c
_{\rm s} $, are spatially constant in the model. We show that the model is
unstable against an axisymmetric perturbation irrespectively of the values of $
v_\phi $ and $ c_{\rm s} $. When the ratio, $ v_\phi / c_{\rm s} $, is large,
the model disk is geometrically thin and unstable against an axisymmetric
perturbation having a short radial wavelength, i.e., unstable against
fragmentation. When $ v_\phi / c_{\rm s} $ is smaller than 1.20, it is unstable
against total collapse. Toomre-Hayashi model of $ 1.7 \la v_\phi / c_{\rm s}
\la 3 $ was thought to be stable against axisymmetric perturbations in earlier
studies in which only radial motion was taken into account. Thus, the
instability of Toomre-Hayashi model having a medium $ v_\phi / c_{\rm s} $ is
due to not change in the surface density but that in the disk height. We also
find that the singular isothermal perturbation is stable against non-spherical
peturbations.

</DOC>
<DOC>
<DOCNO> 13610 </DOCNO>
The critical equation of state of the 2D Ising model


  We compute the 2n-point coupling constants in the high-temperature phase of
the 2d Ising model by using transfer-matrix techniques. This provides the first
few terms of the expansion of the effective potential (Helmholtz free energy)
and of the equation of state in terms of the renormalized magnetization.
 By means of a suitable parametric representation, we determine an analytic
extension of these expansions, providing the equation of state in the whole
critical region in the t,h plane.

</DOC>
<DOC>
<DOCNO> 119484 </DOCNO>
The Mass Assembly and Star Formation Characteristics of Field Galaxies


  We discuss a new method for inferring the stellar mass of a distant galaxy of
known redshift based on the combination of a near-infrared luminosity and
multi-band optical photometry. The typical uncertainty for field galaxies with
I<22 in the redshift range 0<z<1 is a factor 2. We apply this method to a
newly-constructed sample of 321 field galaxies with redshifts and Hubble Space
Telescope morphologies enabling us to construct the stellar mass density
associated with various morphologies as a function of redshift. We find a
marked decline with time in the stellar mass associated with peculiar galaxies
accompanied by a modest rise in that observed for ellipticals. The result
suggests that peculiars decline in abundance because they transform and merge
into regular systems. The star formation rate per unit stellar mass indicates
that massive systems completed the bulk of their star formation before redshift
one, whereas dwarfs continue to undergo major episodes of activity until the
present epoch.

</DOC>
<DOC>
<DOCNO> 122732 </DOCNO>
The effect of projection on the observed gas velocity fields in barred


  The problem of determining the pattern of gas motions in the central cases --
noncircular motions in the triaxial bar potential and motions in circular
orbits but with orientation parameters different from those of the main disk --
are shown to have similar observational manifestations in the line-of-sight
velocity field of the gas. A reliable criterion is needed fo the observational
data to be properly interpreted. To find such a criterion, we analyze
two-dimensional nonlinear hydrodynamics models of gas motions in barred disk
galaxies. The gas line-of-sight velocity and surface brightness distributions
in the plane of the sky are constructed for various inclinations of the
galactic plane to the line-of-sight and bar orientation angles. We show that
using models of circular motions for inclinations $i > 60^\circ$ to analyze the
velocity field can lead to the erroneous conclusions of a ``tilted (polar)
disk'' at the circumnuclear region. However, it is possible to distinguish bars
from tilted disks by comparing the mutual orientations of the photometric and
dynamical axes. As an example, we consider the velocity field of the ionized
gas in the galaxy NGC 972.

</DOC>
<DOC>
<DOCNO> 118657 </DOCNO>
LINER/H II "Transition" Nuclei and the Nature of NGC 4569


  Motivated by the discovery of young, massive stars in the nuclei of some
LINER/H II ``transition'' nuclei such as NGC 4569, we have computed
photoionization models to determine whether some of these objects may be
powered solely by young star clusters rather than by accretion-powered active
nuclei. The models were calculated with the photoionization code CLOUDY, using
evolving starburst continua generated by the the STARBURST99 code of Leitherer
et al. (1999). We find that the models are able to reproduce the emission-line
spectra of transition nuclei, but only for instantaneous bursts of solar or
higher metallicity, and only for ages of ~3-5 Myr, the period when the
extreme-ultraviolet continuum is dominated by emission from Wolf-Rayet stars.
For clusters younger than 3 Myr or older than 6 Myr, and for models with a
constant star-formation rate, the softer ionizing continuum results in an
emission spectrum more typical of H II regions. This model predicts that
Wolf-Rayet emission features should appear in the spectra of transition nuclei.
While such features have not generally been detected to date, they could be
revealed in observations having higher spatial resolution. Demographic
arguments suggest that this starburst model may not apply to the majority of
transition nuclei, particularly those in early-type host galaxies, but it could
account for some members of the transition class in hosts of type Sa and later.
The starburst models during the Wolf-Rayet-dominated phase can also reproduce
the narrow-line spectra of some LINERs, but only under conditions of
above-solar metallicity and only if high-density gas is present (n_e >~ 10^5
cm^{-3}). This scenario could be applicable to some ``Type 2'' LINERs which do
not show any clear signs of nonstellar activity.

</DOC>
<DOC>
<DOCNO> 170022 </DOCNO>
Estimating mixed quantum states


  We discuss single adaptive measurements for the estimation of mixed quantum
states of qubits. The results are compared to the optimal estimation schemes
using collective measurements. We also demonstrate that the advantage of
collective measurements increases when the degree of mixing of the quantum
states increases.

</DOC>
<DOC>
<DOCNO> 71347 </DOCNO>
Transverse energy from minijets in ultrarelativistic nuclear collisions:


  We compute in next-to-leading order (NLO) perturbative QCD the amount of
transverse energy produced into a rapidity region $\Delta Y$ of a nuclear
collision from partons created in the few-GeV subcollisions. The NLO
formulation assumes collinear factorization and is based on the subtraction
method. We first study the results as a function of the minimum transverse
momentum scale and define and determine the associated $K$-factors. The
dependence of the NLO results on the scale choice and on the size of $\Delta Y$
is also studied. The calculations are performed for GRV94 and CTEQ5 sets of
parton distributions. Also the effect of nuclear shadowing to the NLO results
is investigated. The main results are that the NLO results are stable relative
to the leading-order (LO) ones even in the few-GeV domain and that there exists
a new kinematical region not present in the LO, which is responsible for the
magnitude of the $K$-factors. The dependence on the size of $\Delta Y$ is found
to be practically linear within two central units of rapidity, and the scale
dependence present at RHIC energies is seen to vanish at the LHC energies.
Finally, the effect of NLO corrections to the determination of transverse
energies and multiplicities in nuclear collisions is discussed within the
framework of parton saturation.

</DOC>
<DOC>
<DOCNO> 150402 </DOCNO>
String Junction from Non-Commutative Super Yang-Mills Theory


  We construct a 1/4 BPS soliton solution in N=4 non-commutative super
Yang-Mills theory to the first order in the non-commutativity parameter
\theta_{ij}. We then solve the non-commutative eigenvalue equations for the
scalar fields. The Callan-Maldacena interpretation of the eigenvalues precisely
reproduces the expected string junction picture: the string junction is tilted
against the D3-branes with angle \theta_{ij}.

</DOC>
<DOC>
<DOCNO> 121073 </DOCNO>
Accelerated Electrons in Cassiopeia A: An Explanation for the Hard X-ray


  We propose a model for the hard X-ray (> 10 keV) emission observed from the
supernova remnant Cas A. Lower hybrid waves are generated in strong (mG)
magnetic fields, generally believed to reside in this remnant, by shocks
reflected from density inhomogeneities. These then accelerate electrons to
energies of several tens of keV. Around 4% of the x-ray emitting plasma
electrons need to be in this accelerated distribution, which extends up to
electron velocities of order the electron Alfven speed, and is directled along
magnetic field lines. Bremsstrahlung from these electrons produces the observed
hard x-ray emission. Such waves and accelerated electrons have been observed in
situ at Comet Halley, and we discuss the viability of the extrapolation from
this case to the parameters relevant to Cas A.

</DOC>
<DOC>
<DOCNO> 120555 </DOCNO>
Escape of VHE gamma-rays from close massive binary Cen X-3


  We consider propagation of very high energy (VHE) gamma-rays in the radiation
field of a massive star in the binary system Cen X-3, which has been reported
as a source of gamma-ray photons in the GeV and TeV energies. VHE gamma-rays or
electrons, injected by the compact object, should develop inverse Compton pair
cascades. We predict the gamma-ray spectra and light curves for the parameters
of Cen X-3 system. It is found that the gamma-ray spectra, observed at
different directions, have different shape and intensity. The gamma-ray light
curves, produced in the case of electron injection by the compact object in the
Cen X-3 system, should have opposite tendencies for photons with energies above
100 MeV and above 300 GeV, i.e. the photon intensities increases with phase in
the first case and decreases with phase in the second case. However the model
with injection of primary electrons seems to be in contrary with the reported
modulation of the GeV gamma-ray flux with the pulsar's period. The model with
injection of primary photons allows such modulation with the pulsar's period,
but predicts strong modulation of the TeV flux with the orbital period of the
binary. Modulation of TeV emission with the orbital period has been reported by
the early Cherenkov observations, but was not confirmed by the recent, more
sensitive observations by the Durham Mark 6 telescope.

</DOC>
<DOC>
<DOCNO> 169760 </DOCNO>
Controlling decoherence of a two-level-atom in a lossy cavity


  By use of external periodic driving sources, we demonstrate the possibility
of controlling the coherent as well as the decoherent dynamics of a two-level
atom placed in a lossy cavity.
 The control of the coherent dynamics is elucidated for the phenomenon of
coherent destruction of tunneling (CDT), i.e., the coherent dynamics of a
driven two-level atom in a quantum superposition state can be brought
practically to a complete standstill. We study this phenomenon for different
initial preparations of the two-level atom. We then proceed to investigate the
decoherence originating from the interaction of the two-level atom with a lossy
cavity mode. The loss mechanism is described in terms of a microscopic model
that couples the cavity mode to a bath of harmonic field modes. A suitably
tuned external cw-laser field applied to the two-level atom slows down
considerably the decoherence of the atom. We demonstrate the suppression of
decoherence for two opposite initial preparations of the atomic state: a
quantum superposition state as well as the ground state. These findings can be
used to the effect of a proficient battling of decoherence in qubit
manipulation processes.

</DOC>
<DOC>
<DOCNO> 99626 </DOCNO>
Beyond Octonions


  We investigate Clifford Algebras structure over non-ring division algebras.
We show how projection over the real field produces the standard
Attiyah-Bott-Shapiro classification.

</DOC>
<DOC>
<DOCNO> 71493 </DOCNO>
Spin effects in the fragmentation of transversely polarized and


  We study the fragmentation of a transversely polarized quark into a non
collinear (k_T not= 0) spinless hadron and the fragmentation of an unpolarized
quark into a non collinear transversely polarized spin 1/2 baryon. These
nonperturbative properties are described by spin and k_T dependent
fragmentation functions and are revealed in the observation of single spin
asymmetries. Recent data on the production of pions in polarized semi-inclusive
DIS and long known data on Lambda polarization in unpolarized p-N processes are
considered: these new fragmentation functions can describe the experimental
results and the single spin effects in the quark fragmentation turn out to be
surprisingly large.

</DOC>
<DOC>
<DOCNO> 70712 </DOCNO>
Dynamical Quark Effects in QCD on the Lattice - results from the CP-PACS


  Results of a systematic lattice QCD simulation with two degenerate flavors of
sea quarks, identified as dynamical u and d quarks, are presented. The
simulation was performed on a dedicated parallel computer, called CP-PACS,
developed at the University of Tsukuba. Clear dynamical quark effects are
observed in the light hadron mass spectrum and in the light quark masses: In
the light hadron mass spectrum, major parts of the discrepancy between quenched
QCD and experiment are shown to be removed by introducing two flavors of
dynamical quarks. For the averaged mass of u and d quarks, we find
$m_{ud}^{\bar{\rm MS}}(2{\rm GeV}) = 3.44^{+0.14}_{-0.22}$ MeV using the $\pi$
and $\rho$ meson masses as physical input, and for the s quark mass, we obtain
$m_{s}^{\bar{\rm MS}}(2{\rm GeV}) = 88^{+4}_{-6}$ MeV or $90^{+5}_{-11}$ MeV
with the K or $\phi$ meson mass as additional input. These values are about
20-30% smaller than the previous estimates in the quenched approximation. We
also discuss the U(1) problem and B meson decay constants.

</DOC>
<DOC>
<DOCNO> 120905 </DOCNO>
Ultraviolet Galaxy Counts from STIS Observations of the Hubble Deep


  We present galaxy counts in the near-ultraviolet (NUV; 2365\AA) and
far-ultraviolet (FUV; 1595\AA) obtained from Space Telescope Imaging
Spectrograph (STIS) observations of portions of the Hubble Deep Field North
(HDFN), the Hubble Deep Field South (HDFS), and a parallel field near the HDFN.
All three fields have deep (AB$>$29) optical imaging, and we determine
magnitudes by taking the ultraviolet flux detected within the limiting optical
isophote. An analysis of the UV-optical colors of detected objects, combined
with a visual inspection of the UV images, indicates that there are no
detectable objects in the UV images that are not also detected in the optical.
We determine our detection area and completeness as a function of magnitude
with a simulated distribution of galaxies based on the HDFN Wide Field
Planetary Camera 2 (WFPC2) V+I image. The galaxy counts reach to $NUV_{AB}=29$
and $FUV_{AB}=30$, which is 1 magnitude fainter than the HDFN WFPC2/F300W
counts, and 7 magnitudes fainter than balloon-based counts. We integrate our
measurements to present the extragalactic background radiation coming from
resolved objects. The NUV galaxy counts show a flattening or turnover beginning
at about $NUV_{AB}=26.0$, which is not predicted either by no-evolution models
based upon a local luminosity function with a steep faint end slope, nor by a
semi-analytic model in which starbursts are caused by major mergers. The FUV
counts also show a flat slope. We argue that the flat slopes could be caused by
a short duty cycle for star formation, additional starbursts triggered by minor
mergers, and an extended quiescent phase between starburst episodes.

</DOC>
<DOC>
<DOCNO> 67814 </DOCNO>
Supersymmetry and the Brane World


  We investigate the possibility of gravity localization on the brane in the
context of supersymmetric theories. To realize this scenario one needs to find
a theory with the supersymmetric flow stable in IR at two critical points, one
with positive and the other with negative values of the superpotential. We
perform a general study of the supersymmetric flow equations of gauged massless
supergravity interacting with arbitrary number of vector multiplets and
demonstrate that localization of gravity does not occur. The same conclusion
remains true when tensor multiplets are included. We analyze all recent
attempts to find a BPS brane-world and conclude that localization of gravity on
the brane in supersymmetric theories remains a challenging but unsolved
problem.

</DOC>
<DOC>
<DOCNO> 81006 </DOCNO>
The residual mass in Lattice Heavy Quark Effective Theory to alpha^3


  We determine to order alpha^3 in the quenched approximation the so-called
residual mass in the lattice regularisation of the Heavy Quark Effective
Theory. We follow a gauge-invariant strategy which exploits the fact that this
mass term dominates the exponential decrease of perturbative Wilson loops at
large perimeters. Our computational tool is Numerical Stochastic Perturbation
Theory. The new coefficient we compute is crucial to improve the determination
of the (MS bar) mass of the b-quark from lattice simulations of the Heavy Quark
Effective Theory.

</DOC>
<DOC>
<DOCNO> 170694 </DOCNO>
Stochastic Reduction in Nonlinear Quantum Mechanics


  Stochastic extensions of the Schrodinger equation have attracted attention
recently as plausible models for state reduction in quantum mechanics. Here we
formulate a general approach to stochastic Schrodinger dynamics in the case of
a nonlinear state space of the type proposed by Kibble. We derive a number of
new identities for observables in the nonlinear theory, and establish general
criteria on the curvature of the state space sufficient to ensure collapse of
the wave function.

</DOC>
<DOC>
<DOCNO> 170173 </DOCNO>
Entanglement degradation of a two-mode squeezed vacuum in absorbing and


  Applying the recently developed formalism of quantum-state transformation at
absorbing dielectric four-port devices [L.~Kn\"oll, S.~Scheel, E.~Schmidt,
D.-G.~Welsch, and A.V.~Chizhov, Phys. Rev. A {\bf 59}, 4716 (1999)], we
calculate the quantum state of the outgoing modes of a two-mode squeezed vacuum
transmitted through optical fibers of given extinction coefficients. Using the
Peres--Horodecki separability criterion for continuous variable systems
[R.~Simon, Phys. Rev. Lett. {\bf 84}, 2726 (2000)], we compute the maximal
length of transmission of a two-mode squeezed vacuum through an absorbing
system for which the transmitted state is still inseparable. Further, we
calculate the maximal gain for which inseparability can be observed in an
amplifying setup. Finally, we estimate an upper bound of the entanglement
preserved after transmission through an absorbing system. The results show that
the characteristic length of entanglement degradation drastically decreases
with increasing strength of squeezing.

</DOC>
<DOC>
<DOCNO> 100895 </DOCNO>
The Theta Divisor and Three-Manifold Invariants


  In this paper we study an invariant for oriented three-manifolds with
$b_1>0$, which is defined using Heegaard splittings and the theta divisor of a
Riemann surface. The paper is divided into two parts, the first of which gives
the definition of the invariant, and the second of which identifies it with
more classical (torsion) invariants of three-manifolds. Its close relationship
with Seiberg-Witten theory is also addressed.

</DOC>
<DOC>
<DOCNO> 170048 </DOCNO>
Optimal entanglement purifying via entanglement swapping


  It is known that entanglement swapping can be used to realize entanglement
purifying. By this way, two particles belong to different non-maximally
entangled pairs can be projected probabilisticly to a maximally entangled state
or to a less entangled state. In this report, we show, when the less entangled
state is obtained, if a unitary transformation is introduced locally, then a
maximally entangled state can be obtained probabilisticly from this less
entangled state. The total successful probability of our scheme is equal to the
entanglement of a single pairpurification (if two original pairs are in the
same non-maximally entangled states) or to the smaller entanglement of a single
pair purification of these two pairs (if two original pairs are not in the same
non-maximally entangled states). The advantage of our scheme is no continuous
indefinite iterative procedure is needed to achieve optimal purifying.

</DOC>
<DOC>
<DOCNO> 69899 </DOCNO>
Quantum effects, brane tension and large hierarchy in the brane-world


  Semiclassical Einstein's equation in five-dimension with a negative
cosmological constant and conformally invariant bulk matter fields is examined
in the brane world scenario with the S^1/Z_2 compactification. When numbers
N_{b,f} of bosonic and fermionic fields satisfy I<\kappa^2l^{-3}(N_b-N_f)<32I,
we obtain an exact semiclassical solution which has two static branes with
positive tension and for which the warp factor can be arbitrarily large. Here,
\kappa^2 is the five-dimensional gravitational constant, l is a length scale
determined by the negative five-dimensional cosmological constant, and $I$ is a
dimensionless positive constant of order unity. However, in order to obtain a
large warp factor, fine tuning of brane tensions is required. Hence, in order
to solve the hierarchy problem, we need to justify the fine tuning by another
new mechanism.

</DOC>
<DOC>
<DOCNO> 12463 </DOCNO>
Symmetry crossover and excitation thresholds at the neutral-ionic


  Exact ground states, charge densities and excitation energies are found using
valence bond methods for N-site modified Hubbard models with uniform spacing.
At the neutral-ionic transition (NIT), the ground state has a symmetry
crossover in 4n, 4n+2 rings with periodic and antiperiodic boundary conditions,
respectively. The modified Hubbard model has a continuous NIT between a
diamagnetic band insulator on the paired side and a paramagnetic Mott insulator
on the covalent side. The singlet-triplet (ST), singlet-singlet (SS) and charge
gaps for finite N indicate that the ST and SS gaps close at the NIT with
increasing U and that the charge gap vanishes only there. Finite-N excitations
constrain all singularities to about 0.1t of the symmetry crossover. The NIT is
interpreted as a localized ground state (gs) with finite gaps on the paired
side and an extended gs with vanishing ST and SS gaps on the covalent side. The
charge gap and charge stiffness indicate a metallic gs at the transition that,
however, is unconditionally unstable to dimerization.

</DOC>
<DOC>
<DOCNO> 117870 </DOCNO>
Spirals and the size of the disk in EX Dra


  Observations at high spectral and temporal resolution are presented of the
dwarf nova EX Dra in outburst. The disk seen in the He I line reconstructed by
Doppler tomography shows a clear two-armed spiral pattern pointing to spiral
shocks in the disk. The Balmer and He II maps also give evidence for the
presence of spirals. The eclipse as seen in the red continuum indicates a disk
radius of 0.31 times the orbital separation, which might be large enough to
explain the observed spiral shocks through excitation by the tidal field of the
secondary. The eclipse in the Balmer line profiles, well resolved in our
observations, indicates a somewhat smaller disk size (0.25). We discuss the
possibility that this is related to an optical depth effect in the lines.

</DOC>
<DOC>
<DOCNO> 120077 </DOCNO>
Cosmic Dust in the 21st Century


  The past century of interstellar dust has brought us from first ignoring it
to finding that it plays an important role in the evolution of galaxies.
Current observational results in our galaxy provide a complex physical and
chemical evolutionary picture of interstellar dust starting with the formation
of small refractory particles in stellar atmospheres to their modification in
diffuse and molecular clouds and ultimately to their contribution to star
forming regions. Observations of the properties of dust in very young galaxies
will be an important probe of the rates of star formation in terms of the
production and destruction of dust grains. Future observations of dust at high
spectral and spatial resolution will provide detailed information on processes
in collapsing clouds up to star formation. Space missions to comets in the next
century will first study them in situ but ultimately will bring back pristine
nucleus material which will contain the end product of the collapsing
protosolar molecular cloud at the time of planet formation. If one of the
current theories of the origin of life from comets is correct, laboratory
studies of comet dust grains immersed in water may give direct indications of
prebiotic chemical evolution.

</DOC>
<DOC>
<DOCNO> 85369 </DOCNO>
Perturbations of the Kerr spacetime in horizon penetrating coordinates


  We derive the Teukolsky equation for perturbations of a Kerr spacetime when
the spacetime metric is written in either ingoing or outgoing Kerr-Schild form.
We also write explicit formulae for setting up the initial data for the
Teukolsky equation in the time domain in terms of a three metric and an
extrinsic curvature. The motivation of this work is to have in place a
formalism to study the evolution in the ``close limit'' of two recently
proposed solutions to the initial value problem in general relativity that are
based on Kerr-Schild slicings. A perturbative formalism in horizon penetrating
coordinates is also very desirable in connection with numerical relativity
simulations using black hole ``excision''.

</DOC>
<DOC>
<DOCNO> 40405 </DOCNO>
Measurement of the Charged Pion Electromagnetic Form Factor


  Separated longitudinal and transverse structure functions for the reaction
1H(e,eprime pi+)n were measured in the momentum transfer region Q2=0.6-1.6
(GeV/c)**2 at a value of the invariant mass W=1.95 GeV. New values for the pion
charge form factor were extracted from the longitudinal cross section by using
a recently developed Regge model. The results indicate that the pion form
factor in this region is larger than previously assumed and is consistent with
a monopole parameterization fitted to very low Q2 elastic data.

</DOC>
<DOC>
<DOCNO> 117657 </DOCNO>
The Pulse Scale Conjecture and the Case of BATSE Trigger 2193


  The pulses that compose gamma-ray bursts (GRBs) are hypothesized to have the
same shape at all energies, differing only by scale factors in time and
amplitude. This "Pulse Scale Conjecture" is confirmed here between energy
channels of the dominant pulse in GRB 930214c (BATSE trigger 2193), the single
most fluent single-pulsed GRB that occurred before May 1998. Furthermore,
pulses are hypothesized to start at the same time independent of energy. This
"Pulse Start Conjecture" is also confirmed in GRB 930214c. Analysis of GRB
930214c also shows that, in general, higher energy channels show shorter
temporal scale factors. Over the energy range 100 KeV - 1 MeV, it is found that
the temporal scale factors between a pulse measured at different energies are
related to that energy by a power law, possibly indicating a simple
relativistic mechanism is at work. To test robustness, the Pulse Start and
Pulse Scale Conjectures were also tested on the four next most fluent
single-pulse GRBs. Three of the four clearly passed, with a second smaller
pulse possibly confounding the discrepant test. Models where the pulse rise and
decay are created by different phenomena do not typically predict pulses that
satisfy both the Pulse Start Conjecture and the Pulse Scale Conjecture, unless
both processes are seen to undergo common time dilation.

</DOC>
<DOC>
<DOCNO> 9357 </DOCNO>
Self-organized model for information spread in financial markets


  A self-organized model with social percolation process is proposed to
describe the propagations of information for different trading ways across a
social system and the automatic formation of various groups within market
traders. Based on the market structure of this model, some stylized
observations of real market can be reproduced, including the slow decay of
volatility correlations, and the fat tail distribution of price returns which
is found to cross over to an exponential-type asymptotic decay in different
dimensional systems.

</DOC>
<DOC>
<DOCNO> 10886 </DOCNO>
Shear-induced Transitions in Ternary Polymeric System


  The first three-dimensional simulation of shear-induced phase transitions in
a polymeric system has been performed. The method is based on dynamic
density-functional theory. The pathways between a bicontinuous phase with
developing gyroid mesostructure and a lamellar/cylinder phase coexistence are
investigated for a mixture of flexible triblock ABA-copolymer and solvent under
simple steady shear.

</DOC>
<DOC>
<DOCNO> 39915 </DOCNO>
Study of exclusive two-body B0 meson decays to charmonium


  We present a study of three B0 decay modes useful for time-dependent CP
asymmetry measurements. From a sample of 9.7 million B meson pairs collected
with the CLEO detector, we have reconstructed B0 -> J/psi K0S, B0 -> chi_c1
K0S, and B0 -> J/psi pi0 decays. The latter two decay modes have been observed
for the first time. We describe a K0S -> pi0 pi0 detection technique and its
application to the reconstruction of the decay B0 -> J/psi K0S. Combining the
results obtained using K0S -> pi+ pi- and K0S -> pi0 pi0 decays, we determine
Br(B0 -> J/psi K0) = (9.5 +- 0.8 +- 0.6)*10^-4, where the first uncertainty is
statistical and the second one is systematic.
  We also obtain Br(B0 -> chi_c1 K0)= (3.9 +1.9/-1.3 +- 0.4)*10^-4 and Br(B0 ->
J/psi pi0) = (2.5 +1.1/-0.9 +- 0.2)*10^-5.

</DOC>
<DOC>
<DOCNO> 118569 </DOCNO>
Pre-Supernova Evolution of Massive Stars


  We present the preliminary results of a detailed theoretical investigation on
the hydrodynamical properties of Red Supergiant (RSG) stars at solar chemical
composition and for stellar masses ranging from 10 to 20 M_sun. We find that
the main parameter governing their hydrodynamical behavior is the effective
temperature, and indeed when moving from higher to lower effective temperatures
the models show an increase in the dynamical perturbations. Also, we find that
RSGs are pulsationally unstable for a substantial portion of their lifetimes.
These dynamical instabilities play a key role in driving mass loss, thus
inducing high mass loss rates (up to several 1e-4 M_sun/yr) and considerable
variations of the mass loss activity over timescales of the order of 10,000
years. Our results are able to account for the variable mmass loss rates as
implied by radio observations of type II supernovae, and we anticipate that
comparisons of model predictions with observed circumstellar phenomena around
SNII will provide valuable diagnostics about their progenitors and their
evolutionary histories.

</DOC>
<DOC>
<DOCNO> 68870 </DOCNO>
SO(10) theory of R-parity and neutrino mass


  We study the Higgs sector of a SO(10) grand unified theory which predicts
exact conservation of R-parity at all scales and incorporates the see-saw
mechanism. We find possible intermediate scales and light states compatible
with the constraints coming from the running of the gauge couplings. Such a
pattern could lower the SO(10) breaking scale, allowing the d=6 proton decay
operators to be comparable in magnitude to the d=5 ones.

</DOC>
<DOC>
<DOCNO> 174511 </DOCNO>
One-neutron removal reactions on neutron-rich psd-shell nuclei


  A systematic study of high energy, one-neutron removal reactions on 23
neutron-rich, psd--shell nuclei (Z=5-9, A=12-25) has been carried out. The
longitudinal momentum distributions of the core fragments and corresponding
single-neutron removal cross sections are reported for reactions on a carbon
target. Extended Glauber model calculations, weighted by the spectroscopic
factors obtained from shell model calculations, are compared to the
experimental results. Conclusions are drawn regarding the use of such reactions
as a spectroscopic tool and spin-parity assignments are proposed for 15B, 17C,
19-21N, 21,23O, 23-25F. The nature of the weakly bound systems 14B and 15,17C
is discussed.

</DOC>
<DOC>
<DOCNO> 13464 </DOCNO>
Finite temperature oscillations of a Bose-Einstein condensate in a


  The temperature dependence of the frequencies of a Bose-Einstein condensate
obtained in experiment has not been fully understood theoretically. In this
paper we present a simplified version of a two-gas model. A numerically-found
ground state of the system is used for the small-oscillations analysis. In the
case of spherical symmetry a full spectrum of frequencies is found for low
orbital quantum numbers. Avoided crossings that appear in the spectrum might be
the reason for experimentally observed frequency shifts.

</DOC>
<DOC>
<DOCNO> 69168 </DOCNO>
Properties of Strange Hadronic Matter in Bulk and in Finite Systems


  The hyperon-hyperon potentials due to a recent SU(3) Nijmegen soft-core
potential model are incorporated within a relativistic mean field calculation
of strange hadronic matter. We find considerably higher binding energy in bulk
matter compared to several recent calculations which constrain the composition
of matter. For small strangeness fractions, matter is dominated by a
composition of nucleons, Lambdas, and Xis, and the calculated binding energy
closely follows that calculated by using the hyperon potentials of our previous
calculations. For larger strangeness fractions, the calculated binding energy
increases substantially beyond any previous calculation due to a phase
transition into Sigma and Xi dominated matter. We also compare bulk matter
calculations with finite system calculations, again highlighting the
consequences of reducing the Coulomb destabilizing effects in finite strange
systems.

</DOC>
<DOC>
<DOCNO> 11914 </DOCNO>
Ga+, In+ and Tl+ Impurities in Alkali Halide Crystals: Distortion Trends


  A computational study of the doping of alkali halide crystals (AX: A = Na, K;
X = Cl, Br) by ns2 cations (Ga+, In+ and Tl+) is presented. Active clusters of
increasing size (from 33 to 177 ions) are considered in order to deal with the
large scale distortions induced by the substitutional impurities. Those
clusters are embedded in accurate quantum environments representing the
surrounding crystalline lattice. The convergence of the distortion results with
the size of the active cluster is analyced for some selected impurity systems.
The most important conclusion from this study is that distortions along the
(100) and (110) crystallographic directions are not independent. Once a
reliable cluster model is found, distortion trends as a function of impurity,
alkali cation and halide anion are identified and discussed. These trends may
be useful when analycing other cation impurities in similar host lattices.

</DOC>
<DOC>
<DOCNO> 9370 </DOCNO>
Bose-Einstein Condensates in Optical Lattices: Spontaneous Emission in


  An extended Bose-Einstein condensate (BEC) in an optical lattice provides a
kind of periodic dielectric and causes band gaps to occur in the spectrum of
light propagating through it. We examine the question whether these band gaps
can modify the spontaneous emission rate of atoms excited from the BEC, and
whether they can lead to a self-stabilization of the BEC against spontaneous
emission. We find that self-stabilization is not possible for BECs with a
density in the order of $10^{14}$ cm$^{-3}$. However, the corresponding
non-Markovian behavior produces significant effects in the decay of excited
atoms even for a homogeneous BEC interacting with a weak laser beam. These
effects are caused by the occurrence of an avoided crossing in the photon (or
rather polariton) spectrum. We also predict a new channel for spontaneous decay
which arises from an interference between periodically excited atoms and
periodic photon modes. This new channel should also occur in ordinary periodic
dielectrics.

</DOC>
<DOC>
<DOCNO> 102717 </DOCNO>
On quantizing semisimple basic algebras


  We show that there is a consistent polynomial quantization of the coordinate
ring of a basic nilpotent coadjoint orbit of a semisimple Lie group. We also
show, at least in the case of a nilpotent orbit in sl(2,R)*, that any such
quantization is essentially trivial. Furthermore, we prove that the coordinate
ring of a basic semisimple orbit in sl(2,R)* cannot be consistently
polynomially quantized.

</DOC>
<DOC>
<DOCNO> 150644 </DOCNO>
The Dynamics of Collapsing Monopoles and Regular Black Holes


  We study the formation and stability of regular black holes by employing a
thin shell approximation to the dynamics of collapsing magnetic monopoles. The
core deSitter region of the monopole is matched across the shell to a
Reissner-Nordstrom exterior. We find static configurations which are
nonsingular black holes and also oscillatory trajectories about these static
points that share the same causal structure. In these spacetimes the shell is
always hidden behind the black hole horizon. We also find shell trajectories
that pass through the asymptotically flat region and model collapse of a
monopole to form a regular black hole. In addition there are trajectories in
which the deSitter core encompasses a deSitter horizon and hence undergoes
topological inflation. However, these always yield singular black holes and
never have the shell passing through the aymptotically flat region. Although
the regular black hole spacetimes satisfy the strong energy condition, they
avoid the singularity theorems by failing to satisfy the genericity condition
on the Riemann tensor. The regular black holes undergo a change in spatial
topology in accordance with a theorem of Borde's.

</DOC>
<DOC>
<DOCNO> 39946 </DOCNO>
Search for Anomalous ZZgamma and Zgammagamma couplings in the process


  We search for anomalous trilinear gauge couplings in the ZZgamma and
Zgammagamma vertices using data collected with the L3 detector at LEP at a
centre-of-mass energy \sqrt{s}=189 GeV. No evidence is found and limits on
these couplings and on new physics scales are derived from the analysis of the
process e+e- -> Zgamma.

</DOC>
<DOC>
<DOCNO> 100520 </DOCNO>
Rational points near curves and small nonzero |x^3-y^2| via lattice


  We give a new algorithm using linear approximation and lattice reduction to
efficiently calculate all rational points of small height near a given plane
curve C. For instance, when C is the Fermat cubic, we find all integer
solutions of |x^3+y^3-z^3|<M with 0<x<=y<z<N in heuristic time << L(N) M [where
L(X):= (log X)^O(1)] provided M>>N, using only O(log N) space. Since the number
of solutions should be asymptotically proportional to M log N (as long as
M<N^3), the computational costs are essentially as low as possible. Moreover
the algorithm readily parallelizes. It not only yields new numerical examples
but leads to theoretical results, difficult open questions, and natural
generalizations. We also adapt our algorithm to investigate Hall's conjecture:
we find all integer solutions of 0<|x^3-y^2|<<x^(1/2) with x<X in time
O(X^(1/2) L(X)). By implementing this algorithm with X=10^18 we shattered the
previous record for x^(1/2)/|x^3-y^2|. The O(X^{1/2} L(X)) bound is rigorous;
its proof also yields new estimates on the distribution mod 1 of sqrt(cx^3) for
any positive rational c.

</DOC>
<DOC>
<DOCNO> 12006 </DOCNO>
Quantum corrections to the ground state energy of a trapped


  The diffusion Monte Carlo method is applied to describe a trapped atomic
Bose-Einstein condensate at zero temperature, fully quantum mechanically and
nonperturbatively. For low densities, $n(0)a^3 \le 2 \cdot 10^{-3}$ [n(0): peak
density, a: s-wave scattering length], our calculations confirm that the exact
ground state energy for a sum of two-body interactions depends on only the
atomic physics parameter a, and no other details of the two-body model
potential. Corrections to the mean-field Gross-Pitaevskii energy range from
being essentially negligible to about 20% for N=2-50 particles in the trap with
positive s-wave scattering length a=100-10000 a.u.. Our numerical calculations
confirm that inclusion of an additional effective potential term in the
mean-field equation, which accounts for quantum fluctuations [see e.g. E.
Braaten and A. Nieto, Phys. Rev. B 56}, 14745 (1997)], leads to a greatly
improved description of trapped Bose gases.

</DOC>
<DOC>
<DOCNO> 102621 </DOCNO>
Poisson Geometry of Discrete Series Orbits, and Momentum Convexity for


  The main result of this paper is a convexity theorem for momentum mappings of
certain hamiltonian actions of noncompact semisimple Lie groups. The image is
required to fall within a certain open subset D of the (dual of the) Lie
algebra, and the momentum map itself is required to be proper as a map to D.
The set D corresponds roughly, via the orbit method, to the discrete series of
representations of the group,
  Much of the paper is devoted to the study of D itself, which consists of the
Lie algebra elements which have compact centralizer. When the group is Sp(2n),
these elements are the ones which are called "strongly stable" in the theory of
linear hamiltonian dynamical systems, and our results may be seen as a
generalization of some of that theory to arbitrary semisimple Lie groups.
  As an application, we prove a new convexity theorem for the frequency sets of
sums of positive definite hamiltonians with prescribed frequencies.

</DOC>
<DOC>
<DOCNO> 10990 </DOCNO>
Actively Contracting Bundles of Polar Filaments


  We introduce a phenomenological model to study the properties of bundles of
polar filaments which interact via active elements. The stability of the
homogeneous state, the attractors of the dynamics in the unstable regime and
the tensile stress generated in the bundle are discussed. We find that the
interaction of parallel filaments can induce unstable behavior and is
responsible for active contraction and tension in the bundle. Interaction
between antiparallel filaments leads to filament sorting. Our model could apply
to simple contractile structures in cells such as stress fibers.

</DOC>
<DOC>
<DOCNO> 84181 </DOCNO>
Quaternionic metrics from harmonic superspace : lagrangian approach and


  Starting from the most general harmonic superspace action of self-interacting
Q^+ hypermultiplets in the background of N=2 conformal supergravity, we derive
the general action for the bosonic sigma model with a generic 4n dimensional
quaternionic-Kahler (QK) manifold as the target space. The action is determined
by the analytic harmonic QK potential. We find out this action to have two flat
limits. One gives the hyper-Kahler sigma model with a 4n dimensional target
manifold, while another yields a conformally invariant sigma model with 4(n+1)
dimensional hyper-Kahler target. We work out the harmonic superspace version of
the QK quotient construction and use it to give a new derivation of QK
extensions of Taub-NUT and Eguchi-Hanson metrics. We analyze in detail the
geometrical and symmetry structure of the second metric. The QK sigma model
approach allows us to reveal the enhancement of its isometry group to SU(3) or
SU(2,1) at the special relations between its parameters : the Einstein constant
and the "mass".

</DOC>
<DOC>
<DOCNO> 122153 </DOCNO>
Toward a Standard Model of Core Collapse Supernovae


  In this paper, we discuss the current status of core collapse supernova
models and the future developments needed to achieve significant advances in
understanding the supernova mechanism and supernova phenomenology, i.e., in
developing a supernova standard model.

</DOC>
<DOC>
<DOCNO> 117595 </DOCNO>
Analysis of The Hipparcos Measurements of HD10697 - A Mass Determination


  HD10697 is a nearby main-sequence star around which a planet candidate has
recently been discovered by means of radial-velocity measurements (Vogt et al.
1999, submitted to ApJ). The stellar orbit has a period of about three years,
the secondary minimum mass is 6.35 Jupiter masses and the minimum semi-major
axis is 0.36 milli-arc-sec (mas). Using the Hipparcos data of HD10697 together
with the spectroscopic elements of Vogt et al. (1999) we found a semi-major
axis of 2.1 +/- 0.7 mas, implying a mass of 38 +/- 13 Jupiter masses for the
unseen companion. We therefore suggest that the secondary of HD10697 is
probably a brown dwarf, orbiting around its parent star at a distance of 2 AU.

</DOC>
<DOC>
<DOCNO> 10371 </DOCNO>
Instability of the symmetric Couette-flow in a granular gas:


  We investigate the inelastic hard disk gas sheared by two parallel bumpy
walls (Couette-flow). In our molecular dynamic simulations we found a
sensitivity to the asymmetries of the initial condition of the particle places
and velocities and an asymmetric stationary state, where the deviation from
(anti)symmetric hydrodynamic fields is stronger as the normal restitution
coefficient decreases. For the better understanding of this sensitivity we
carried out a linear stability analysis of the former kinetic theoretical
solution [Jenkins and Richman: J. Fluid. Mech. {\bf 171} (1986)] and found it
to be unstable. The effect of this asymmetry on the self-diffusion coefficient
is also discussed.

</DOC>
<DOC>
<DOCNO> 170627 </DOCNO>
Quantum Algorithmic Entropy


  We extend algorithmic information theory to quantum mechanics, taking a
universal semicomputable density matrix (``universal probability'') as a
starting point, and define complexity (an operator) as its negative logarithm.
  A number of properties of Kolmogorov complexity extend naturally to the new
domain. Approximately, a quantum state is simple if it is within a small
distance from a low-dimensional subspace of low Kolmogorov complexity. The von
Neumann entropy of a computable density matrix is within an additive constant
from the average complexity. Some of the theory of randomness translates to the
new domain.
  We explore the relations of the new quantity to the quantum Kolmogorov
complexity defined by Vitanyi (we show that the latter is sometimes as large as
2n - 2log n and the qubit complexity defined by Berthiaume, Dam and Laplante.
The ``cloning'' properties of our complexity measure are similar to those of
qubit complexity.

</DOC>
<DOC>
<DOCNO> 169827 </DOCNO>
Stability properties of trapped Bose-Fermi gases mixture


  The stability of Bose-Fermi gases trapped in an isotropic potentials at
ultracold temperature is strongly influenced by the interaction between the
fermions and the bosons. At zero temperature, the stability criterion is given
in this paper using variation method, the results show that whether a
fermion-boson mixture is stable depends mainly on the interaction between the
fermions and the bosons. For finite temperature, however, the stability is not
only related to the coupling constants, but also to the temperature. The
stability conditions for finite temperature are also derived and discuss in
details in this paper.

</DOC>
<DOC>
<DOCNO> 10222 </DOCNO>
Charge and Orbital Ordering and Spin State Transition Driven by


  We have investigated electronic structures of antiferromagnetic YBaCo_2O_5
using the local spin-density approximation (LSDA) + U method. The charge and
orbital ordered insulating ground state is correctly obtained with the strong
on-site Coulomb interaction. Co^{2+} and Co^{3+} ions are found to be in the
high spin (HS) and intermediate spin (IS) state, respectively. It is considered
that the tetragonal to orthorhombic structural transition is responsible for
the ordering phenomena and the spin states of Co ions. The large contribution
of the orbital moment to the total magnetic moment indicates that the
spin-orbit coupling is also important in YBaCo_2O_5.

</DOC>
<DOC>
<DOCNO> 72126 </DOCNO>
On Cosmological Perturbations on a Brane in an Anti-de Sitter Bulk


  In this paper, we consider cosmological perturbations on a brane universe
embedded in an Anti-de Sitter bulk. We use a novel gauge, in which the full
five-dimensional problem is in principle solvable. In this gauge we derive the
equations for scalar, vector and tensor perturbations. These equations are
necessary in order to calculate microwave background anisotropies in this
particular scenario. Throughout the paper, we draw attention to the influence
of the bulk gravitons, which act as a source for the perturbations on the
brane. In addition, we find that isocurvature modes are generated due to the
influence of bulk gravitons.

</DOC>
<DOC>
<DOCNO> 102516 </DOCNO>
Homological properties of bigraded algebras


  We study the x- and y-regularity of a bigraded K-algebra R. These notions are
used to study asymptotic properties of certain finitely generated bigraded
modules. As an application we get for any equigenerated graded ideal I upper
bounds for the number j_0 for which reg(I^j) is a linear function for j >= j_0.
Finally we give upper bounds for the x- and y-regularity of generalized
Veronese algebras.

</DOC>
<DOC>
<DOCNO> 102088 </DOCNO>
The Dirac Operator on Hyperbolic Manifolds of Finite Volume


  We study the spectrum of the Dirac operator on hyperbolic manifolds of finite
volume. Depending on the spin structure it is either discrete or the whole real
line. For link complements in S^3 we give a simple criterion in terms of
linking numbers for when essential spectrum can occur. We compute the
accumulation rate of the eigenvalues of a sequence of closed hyperbolic 2- or
3-manifolds degenerating into a noncompact hyperbolic manifold of finite
volume. It turns out that in three dimensions there is no clustering at all.

</DOC>
<DOC>
<DOCNO> 118054 </DOCNO>
Spectroscopic Constraints on the Stellar Population of Elliptical


  Near-IR spectra for a sample of 31 elliptical galaxies in the Coma cluster
are obtained. The galaxies are selected to be ellipticals (no lenticulars),
with a large spatial distribution, covering both the core and outskirt of the
cluster (ie. corresponding to regions with large density contrasts).
Spectroscopic CO (2.3 micron) absorption indices, measuring contribution from
intermediate-age red giant and supergiant stars to the near-IR light of the
ellipticals, are then estimated.
  It is found that the strength of spectroscopic CO features in elliptical
galaxies increases from the core (r < 0.2 deg) to the outskirts (r > 0.2 deg)
of the Coma cluster. Using the Mg2 strengths, it is shown that the observed
effect is not due to metallicity and is mostly caused by the presence of a
younger population (giant and supergiant stars) in ellipticals in outskirts
(low density region) of the cluster.
  Using the spectroscopic CO features, the origin of the scatter on the near-IR
Fundamental Plane of elliptical galaxies is studied. Correcting this relation
for contributions from the red giant and supergiant stars, the rms scatter
reduces from 0.077dex to 0.073dex. Although measurable, the contribution from
these intermediate-age stars to the scatter on the near-IR Fundamental Plane of
ellipticals is only marginal.
  A relation is found between the CO and V-K colours of ellipticals with a
slope 0.036 +/- 0.016. This is studied using stellar synthesis models.

</DOC>
<DOC>
<DOCNO> 118826 </DOCNO>
Mode identification of Pulsating White Dwarfs using the HST


  We have obtained time-resolved ultraviolet spectroscopy for the pulsating DAV
stars G226-29 and G185-32, and for the pulsating DBV star PG1351+489 with the
Hubble Space Telescope Faint Object Spectrograph, to compare the ultraviolet to
the optical pulsation amplitude and determine the pulsation indices. We find
that for essentially all observed pulsation modes, the amplitude rises to the
ultraviolet as the theoretical models predict for l=1 non-radial g-modes. We do
not find any pulsation mode visible only in the ultraviolet, nor any modes
whose phase flips by 180 degrees; in the ultraviolet, as would be expected if
high l pulsations were excited. We find one periodicity in the light curve of
G185-32, at 141 s, which does not fit theoretical models for the change of
amplitude with wavelength of g-mode pulsations.

</DOC>
<DOC>
<DOCNO> 122123 </DOCNO>
A stellar fly-by simulation giving Beta Pic's disc asymmetries


  We have numerically investigated the dynamics of how a close stellar fly-by
encounter of a symmetrical circumstellar planetesimal disc can give rise to the
many kinds of asymmetries and substructures attributed to the dusty disc of
Beta Pic. We find three recognizable groupings of test particles that can be
related to the morphology of the Beta Pic disc. These are: highly eccentric and
inclined orbit particles that reach apocentre in the southwest, moderately
eccentric and inclined orbit particles that reach apocentre in the northeast,
and a relatively unperturbed region inside ~200au radius.

</DOC>
<DOC>
<DOCNO> 7671 </DOCNO>
Scale Dependent Dimension of Luminous Matter in the Universe


  We present a geometrical model of the distribution of luminous matter in the
universe, derived from a very simple reaction-diffusion model of turbulent
phenomena. The apparent dimension of luminous matter, $D(l)$, depends linearly
on the logarithm of the scale $l$ under which the universe is viewed: $D(l)
\sim 3\log(l/l_0)/\log(\xi/l_0)$, where $\xi$ is a correlation length.
Comparison with data from the SARS red-shift catalogue, and the LEDA database
provides a good fit with a correlation length $\xi \sim 300$ Mpc. The
geometrical interpretation is clear: At small distances, the universe is
zero-dimensional and point-like. At distances of the order of 1 Mpc the
dimension is unity, indicating a filamentary, string-like structure; when
viewed at larger scales it gradually becomes 2-dimensional wall-like, and
finally, at and beyond the correlation length, it becomes uniform.

</DOC>
<DOC>
<DOCNO> 85036 </DOCNO>
The large cosmological constant approximation to classical and quantum


  We have recently introduced an approach for studying perturbatively classical
and quantum canonical general relativity. The perturbative technique appears to
preserve many of the attractive features of the non-perturbative quantization
approach based on Ashtekar's new variables and spin networks. With this
approach one can find perturbatively classical observables (quantities that
have vanishing Poisson brackets with the constraints) and quantum states
(states that are annihilated by the quantum constraints). The relative ease
with which the technique appears to deal with these traditionally hard problems
opens several questions about how relevant the results produced can possibly
be. Among the questions is the issue of how useful are results for large values
of the cosmological constant and how the approach can deal with several
pathologies that are expected to be present in the canonical approach to
quantum gravity. With the aim of clarifying these points, and to make our
construction as explicit as possible, we study its application in several
simple models. We consider Bianchi cosmologies, the asymmetric top, the coupled
harmonic oscillators with constant energy density and a simple quantum
mechanical system with two Hamiltonian constraints. We find that the technique
satisfactorily deals with the pathologies of these models and offers promise
for finding (at least some) results even for small values of the cosmological
constant. Finally, we briefly sketch how the method would operate in the full
four dimensional quantum general relativity case.

</DOC>
<DOC>
<DOCNO> 122211 </DOCNO>
Detection of an X-ray periodicity in the Narrow-line Seyfert 1 Galaxy


  We have analyzed the timing properties of the Narrow-line Seyfert 1 galaxy
Mrk 766 observed with XMM-Newton during the PV phase. The source intensity
changes by a factor of 1.3 over the 29,000 second observation. If the soft
excess is modeled by a black body component, as indicated by the EPIC pn data,
the luminosity of the black body component scales with its temperature
according to L ~ T^4. This requires a lower limit 'black body size` of about
1.3*10^25 cm^2. In addition, we report the detection of a strong periodic
signal with 2.4*10^-4 Hz. Simulations of light curves with the observed time
sequence and phase randomized for a red noise spectrum clearly indicate that
the periodicity peak is intrinsic to the distant AGN. Furthermore, its
existence is confirmed by the EPIC MOS and RGS data. The spectral fitting
results show that the black body temperature and the absorption by neutral
hydrogen remain constant during the periodic oscillations. This observational
fact tends to rule out models in which the intensity changes are due to hot
spots orbiting the central black hole. Precession according to the
Bardeen-Petterson effect or instabilities in the inner accretion disk may
provide explanations for the periodic signal.

</DOC>
<DOC>
<DOCNO> 150862 </DOCNO>
Dimensional Transmutation and Dimensional Regularization in Quantum


  A thorough analysis is presented of the class of central fields of force that
exhibit: (i) dimensional transmutation and (ii) rotational invariance. Using
dimensional regularization, the two-dimensional delta-function potential and
the $D$-dimensional inverse square potential are studied. In particular, the
following features are analyzed: the existence of a critical coupling, the
boundary condition at the origin, the relationship between the bound-state and
scattering sectors, and the similarities displayed by both potentials. It is
found that, for rotationally symmetric scale-invariant potentials, there is a
strong-coupling regime, for which quantum-mechanical breaking of symmetry takes
place, with the appearance of a unique bound state as well as of a logarithmic
energy dependence of the scattering with respect to the energy.

</DOC>
<DOC>
<DOCNO> 102487 </DOCNO>
Statistical stability for robust classes of maps with non-uniform


  We consider open sets of maps in a manifold $M$ exhibiting non-uniform
expanding behaviour in some domain $S\subset M$. Assuming that there is a
forward invariant region containing $S$ where each map has a unique SRB
measure, we prove that under general uniformity conditions, the SRB measure
varies continuously in the $L^1$-norm with the map. As a main application we
show that the open class of maps introduced in [V] fits to this situation, thus
proving that the SRB measures constructed in [A] vary continuously with the
map.

</DOC>
<DOC>
<DOCNO> 150525 </DOCNO>
Self-Duality beyond Chiral p-Form Actions


  The self-duality of chiral p-forms was originally investigated by Pasti,
Sorokin and Tonin in a manifestly Lorentz covariant action with non-polynomial
auxiliary fields. The investigation was then extended to other chiral p-form
actions. In this paper we point out that the self-duality appears in a wider
context of theoretical models that relate to chiral p-forms. We demonstrate
this by considering the interacting model of Floreanini-Jackiw chiral bosons
and gauge fields, the generalized chiral Schwinger model (GCSM) and the
latter's gauge invariant formulation, and discover that the self-duality of the
GCSM corresponds to the vector and axial vector current duality.

</DOC>
<DOC>
<DOCNO> 123335 </DOCNO>
Low-mass quark stars as Maclaurin spheroids


  We show that in the limit of low masses (M<0.1M solar), the orbital and
rotational frequencies in exact relativistic numerical models of rotating,
axially symmetric, quark stars coincide with those for Maclaurin spheroids. In
particular, when the eccentricity of the spheroid exceeds a critical value
(e>0.83458318), circular orbits in the equatorial plane are unstable for a
range of orbital radii outside the stellar surface. The orbital frequency in
the marginally stable orbit, and all other orbits, around Maclaurin spheroids
goes to zero in the limit e=1. Maximum orbital frequencies in accreting
Galactic X-ray sources may be a poor indication of the source mass.

</DOC>
<DOC>
<DOCNO> 121319 </DOCNO>
Monte Carlo simulations of star clusters - II. Tidally limited,


  A revision of Stod\{'o}{\l}kiewicz's Monte Carlo code is used to simulate
evolution of large star clusters. A survey of the evolution of N-body systems
influenced by the tidal field of a parent galaxy and by stellar evolution is
presented. The results presented are in good agreement with theoretical
expectations and the results of other methods (Fokker-Planck, Monte Carlo and
N-body). The initial rapid mass loss, due to stellar evolution of the most
massive stars, causes expansion of the whole cluster and eventually leads to
the disruption of less bound systems ($W_0=3$). Models with larger $W_0$
survive this phase of evolution and then undergo core collapse and subsequent
post-collapse expansion, like isolated models. The expansion phase is
eventually reversed when tidal limitation becomes important. The results
presented are the first major step in the direction of simulating evolution of
real globular clusters by means of the Monte Carlo method.

</DOC>
<DOC>
<DOCNO> 102785 </DOCNO>
Invitation to higher local fields, Part II, section 1: Higher


  This work describes several first steps in extending Tate-Iwasawa's analytic
method to define an L-function in higher dimensions. For generalizing this
method the author advocates the usefulness of the classical Riemann-Hecke
approach, his adelic complexes together with his generalization of Krichever's
correspondence. He analyzes dimension 1 types of functions and discusses
properties of the lattice of commensurable classes of subspaces in the adelic
space associated to a divisor on an algebraic surface.

</DOC>
<DOC>
<DOCNO> 118265 </DOCNO>
Constraining the Lifetime of Quasars from their Spatial Clustering


  The lifetime t_Q of the luminous phase of quasars is constrained by current
observations to be between 10^6 and 10^8 years, but is otherwise unkown. We
model the quasar luminosity function in detail in the optical and X-ray bands
using the Press-Schechter formalism, and show that the expected clustering of
quasars depends strongly on their assumed lifetime. We quantify this
dependence, and find that existing measurements of the correlation length of
quasars are consistent with the range 10^6 < t_Q < 10^8 years. We then show
that future measurements of the power spectrum of quasars out to z=3, from the
2dF or Sloan Digital Sky Survey, can significantly improve this constraint, and
in principle allow a precise determination of t_Q. We estimate the systematic
errors introduced by uncertainties in the modeling of the quasar-halo
relationship, as well as by the possible existence of obscured quasars.

</DOC>
<DOC>
<DOCNO> 102274 </DOCNO>
Random Delaunay triangulations, the Thurston-Andreev theorem, and metric


  In this thesis a connection between the worlds of discrete and continuous
conformal geometry is explored. Specifically, a disk pattern production theroem
is proved using an energy which measures how ``uniform'' the angle data of a
triangulation is, see also math.DG/0002150. Then this energy is averaged over
all the Delaunay triangulation of a Riemannian surface to form an energy
measuring how ``uniform'' a metric is, see also math.DG/0010316.

</DOC>
<DOC>
<DOCNO> 72045 </DOCNO>
Four--Neutrino Oscillations at SNO


  We discuss the potential of the Sudbury Neutrino Observatory (SNO) to
constraint the four--neutrino mixing schemes favoured by the results of all
neutrino oscillations experiments. Our results show that some information on
the value of $\cos^2(\vartheta_{23}) \cos^2(\vartheta_{24})$ can be obtained by
the first SNO measurement of the CC ratio, while considerable improvement on
the knowledge of this mixing will be achievable after the measurement of the
NC/CC ratio.

</DOC>
<DOC>
<DOCNO> 152328 </DOCNO>
On the Cohomological Structure of Supersymmetric Lagrangeans With and


  The origin of non-renormalization theorems in field theories with global
supersymmetry can be traced to the fact that supersymmetric actions can be
viewed as the highest components of respective supermultiplets. Supersymmetric
interactions in particular can therefore be represented as supersymmetry
variations of lower dimensional field polynomials. We investigate here this
algebraic structure in the context of the Wess-Zumino model and N=1 and N=2
supersymmetric Yang-Mills theories.

</DOC>
<DOC>
<DOCNO> 99563 </DOCNO>
F-regular and F-pure rings vs. log terminal and log canonical


  In this paper, we investigate the relationship of F-regular (resp. F-pure)
rings and log terminal (resp. log canonical) singularities. Also, we extend the
notions of F-regularity and F-purity to "F-singularities of pairs." The notions
of F-regular and F-pure rings in characteristic $p>0$ are characterized by a
splitting of the Frobenius map, and define some classes of rings having "mild"
singularities. On the other hand, there are notions of log terminal and log
canonical singularities defined via resolutions of singularities in
characteristic zero. These are defined also for pairs of a normal variety and a
$\Bbb Q$-divisor $\Delta$ on it, and play an important role in birational
algebraic geometry. As an analog of these singularities of pairs in
characteristic zero, we define the notions of "F-singularities of pairs,"
namely strong F-regularity, divisorial F-regularity and F-purity for a pair
$(A,\Delta)$ of a normal ring $A$ of characteristic $p > 0$ and an effective
$\Bbb Q$-divisor $\Delta$ on $Y = Spec A$. The main theorem of this paper
asserts that, if $K_Y + \Delta$ is $\Bbb Q$-Cartier, then the above three
variants of F-singularitiesof pairs imply KLT, PLT and LC properties,
respectively. We also prove some results for F-singularities of pairs which are
analoguous to singularities of pairs in characteristic zero.

</DOC>
<DOC>
<DOCNO> 118653 </DOCNO>
The Evolution of the Stellar Hosts of Radio Galaxies


  We present new near-infrared images of z>0.8 radio galaxies from the
flux-limited 7C-III sample of radio sources for which we have recently obtained
almost complete spectroscopic redshifts. The 7C objects have radio luminosities
about 20 times fainter than 3C radio galaxies at a given redshift. The absolute
magnitudes of the underlying host galaxies and their scale sizes are only
weakly dependent on radio luminosity. Radio galaxy hosts at z~2 are
significantly brighter than the hosts of radio-quiet quasars at similar
redshifts and the model AGN hosts of Kauffmann & Haehnelt (2000). There is no
evidence for strong evolution in scale size, which shows a large scatter at all
redshifts. The hosts brighten significantly with redshift, consistent with the
passive evolution of a stellar population that formed at z>~3. This scenario is
consistent with studies of host galaxy morphology and submillimeter continuum
emission, both of which show strong evolution at z>~2.5. The lack of a strong
``redshift cutoff'' in the radio luminosity function to z>4 suggests that the
formation epoch of the radio galaxy host population lasts >~1Gyr from z>~5 to
z~3. We suggest these facts are best explained by models in which the most
massive galaxies and their associated AGN form early due to high baryon
densities in the centres of their dark matter haloes.

</DOC>
<DOC>
<DOCNO> 150501 </DOCNO>
Triplectic Quantization of W2 gravity


  The role of one loop order corrections in the triplectic quantization is
discussed in the case of W2 theory. This model illustrates the presence of
anomalies and Wess Zumino terms in this quantization scheme where extended BRST
invariance is represented in a completely anticanonical form.

</DOC>
<DOC>
<DOCNO> 117976 </DOCNO>
Expected Number and Flux Distribution of Gamma-Ray-Burst Afterglows with


  If Gamma-Ray-Bursts (GRBs) occur at high redshifts, then their bright
afterglow emission can be used to probe the ionization and metal enrichment
histories of the intervening intergalactic medium during the epoch of
reionization. In contrast to other sources, such as galaxies or quasars, which
fade rapidly with increasing redshift, the observed infrared flux from a GRB
afterglow at a fixed observed age is only a weak function of its redshift. This
results from a combination of the spectral slope of GRB afterglows and the
time-stretching of their evolution in the observer's frame. Assuming that the
GRB rate is proportional to the star formation rate and that the characteristic
energy output of GRBs is ~10^{52} ergs, we predict that there are always ~15
GRBs from redshifts z>5 across the sky which are brighter than ~100 nJy at an
observed wavelength of ~2 \mu m. The infrared spectrum of these sources could
be taken with the future Next Generation Space Telescope, as a follow-up on
their early X-ray localization with the Swift satellite.

</DOC>
<DOC>
<DOCNO> 68332 </DOCNO>
Manifestaion of SUSY in B decays


  SUSY effects on various flavor changing neutral current processes are
discussed in the minimal supergravity model and the SU(5) grand unified theory
with right-handed neutrino supermultiplets. In particular, in the latter case
the neutrino Yukawa coupling constants can be a source of the flavor mixing in
the right-handed-down-type-squark sector. It is shown that due to this mixing
the time-dependent CP asymmetry of radiative B decay can be as large as 30% and
the ratio of $B_s$-$\bar{B}_s$ mixing and $B_d$-$\bar{B}_d$ mixing deviates
from the prediction in the standard model and the minimal supergravity model
without the neutrino interaction.

</DOC>
<DOC>
<DOCNO> 11361 </DOCNO>
Order by disorder from non-magnetic impurities in a two-dimensional


  We consider doping of non-magnetic impurities in the spin-1/2, 1/5-depleted
square lattice. This structure, whose undoped phase diagram offers both
magnetically ordered and spin-liquid ground states, is realized physically in
CaV_4O_9. Doping into the ordered phase results in a progressive loss of order,
which becomes complete at the percolation threshold. By contrast, non-magnetic
impurities introduced in the spin liquids create a phase of weak but
long-ranged antiferromagnetic order coexisting with the gapped state. The
latter may be viewed as a true order-by-disorder phenomenon. We study the phase
diagram of the doped system by computing the static susceptibility and
staggered magnetization using a stochastic series-expansion quantum Monte Carlo
technique.

</DOC>
<DOC>
<DOCNO> 68389 </DOCNO>
Ultra High Energy Cosmic Rays from Axion Stars


  We propose a model in which ultra high energy cosmic rays are produced by
collisions between neutron stars and axion stars. The acceleration of such a
cosmic ray is made by the electric field, $\sim 10^{15} (B/10^{12} {G}) {eV}
{cm}^{-1}$, which is induced in an axion star by the strong magnetic field
$B>10^{12}$ G of a neutron star. As we have shown previously, similar
collisions generate gamma ray bursts when the magnetic field is much smaller,
e.g. $\sim 10^{10}$ G. If we assume that the axion mass is $\sim 10^{-9}$ eV,
we can explain huge energies of the gamma ray bursts $\sim 10^{54}$ erg as well
as the ultra high energies of the cosmic rays $\sim 10^{20}$ eV. In addition,
it turns out that these axion stars are plausible candidates for MACHOs. We
point out a possibility of observing monochromatic radiations emitted from the
axion stars.

</DOC>
<DOC>
<DOCNO> 120195 </DOCNO>
Dwarf galaxy formation induced by galaxy interactions


  Growing evidence has been accumulated for that some gas-rich dwarf galaxies
are formed from material liberated by galaxy collisions and/or mergers. Also,
gas-poor dwarf elliptical galaxies are often found in the central regions of
clusters of galaxies. These observations suggest strongly that the formation of
most dwarf galaxies is linked to galaxy interactions. Therefore, now seems like
the right time to investigate the formation efficiency of such tidal dwarf
galaxies. Adopting the galaxy interaction scenario proposed by Silk & Norman,
we find that if only a few dwarf galaxies are formed in each galaxy collision,
we are able to explain the observed morphology-density relations for both dwarf
and giant galaxies in the field, groups of galaxies, and clusters of galaxies.
It seems worthwhile noting that the tidal dwarf formation may be coupled with
the transformation from gas-rich disk galaxies to early-type galaxies such as
S0 and elliptical galaxies.

</DOC>
<DOC>
<DOCNO> 40295 </DOCNO>
Experimental Status of Semileptonic B Decays - Recent Results from LEP


  Recent analyses of the LEP and Y(4S) data have better outlined the picture of
semileptonic B decays. Results on inclusive and exclusive decay branching
fractions and on the extraction of the Vub and Vcb elements of the CKM mixing
matrix are discussed, together with some of the still open questions and the
sources of model systematics.

</DOC>
<DOC>
<DOCNO> 122221 </DOCNO>
A 10-micron Search for Inner-Truncated Disks Among Pre-Main-Sequence


  We use mid-IR (primarily 10 $\mu$m) photometry as a diagnostic for the
presence of disks with inner cavities among 32 pre-main sequence stars in Orion
and Taurus-Auriga for which rotation periods are known and which do not show
evidence for inner disks at near-IR wavelengths. Disks with inner cavities are
predicted by magnetic disk-locking models that seek to explain the regulation
of angular momentum in T Tauri stars. Only three stars in our sample show
evidence for excess mid-IR emission. While these three stars may possess
truncated disks consistent with magnetic disk-locking models, the remaining 29
stars in our sample do not. Apparently, stars lacking near-IR excesses in
general do not possess truncated disks to which they are magnetically coupled.
  We discuss the implications of this result for the hypothesis of
disk-regulated angular momentum. Evidently, young stars can exist as slow
rotators without the aid of present disk-locking, and there exist very young
stars already rotating near breakup velocity whose subsequent angular momentum
evolution will not be regulated by disks. Moreover, we question whether disks,
when present, truncate in the manner required by disk-locking scenarios.
Finally, we discuss the need for rotational evolution models to take full
account of the large dispersion of rotation rates present at 1 Myr, which may
allow the models to explain the rotational evolution of low-mass pre-main
sequence stars in a way that does not depend upon braking by disks.

</DOC>
<DOC>
<DOCNO> 83182 </DOCNO>
Programming in Alma-0, or Imperative and Declarative Programming


  In (Apt et al, TOPLAS 1998) we introduced the imperative programming language
Alma-0 that supports declarative programming. In this paper we illustrate the
hybrid programming style of Alma-0 by means of various examples that complement
those presented in (Apt et al, TOPLAS 1998). The presented Alma-0 programs
illustrate the versatility of the language and show that ``don't know''
nondeterminism can be naturally combined with assignment.

</DOC>
<DOC>
<DOCNO> 13304 </DOCNO>
Is there a vortex-glass transition in high-temperature superconductors?


  We show that DC voltage versus current measurements of a YBCO micro-bridge in
a magnetic field can be collapsed onto scaling functions proposed by Fisher,
Fisher, and Huse, as is widely reported in the literature. We find, however,
that good data collapse is achieved for a wide range of critical exponents and
temperatures. These results strongly suggest that agreement with scaling alone
does not prove the existence of a phase transition. We propose a criterion to
determine if the data collapse is valid, and thus if a phase transition occurs.
To our knowledge, none of the data reported in the literature meet our
criterion.

</DOC>
<DOC>
<DOCNO> 13594 </DOCNO>
The point-splitting regularization of (2+1)d parity breaking models


  The coefficient of the Chern-Simons term in the effective action for massive
Dirac fermions in three dimensions is computed by using the point-splitting
regularization method. We show that in this framework no ambiguities arise.
This is related to the fact that the point-splitting regularization does not
introduce additional parity breaking effects, implementing one possible
physical criterion in order to uniquely characterize the system.

</DOC>
<DOC>
<DOCNO> 13498 </DOCNO>
Possible robust insulator-superconductor transition on solid inert gas


  We present observations of the insulator-superconductor transition in
ultrathin films of Bi on amorphous quartz, quartz coated with Ge, and for the
first time, solid xenon condensed on quartz. The relative permeability
$\epsilon_r$ ranges from 1.5 for Xe to 15 for Ge. Though we find screening
effects as expected, the I-S transition is robust, and unmodified by the
substrate. The resistance separatrix is found to be close to h/4e^2 and the
crossover thickness close to $\rm 25 \AA$ for all substrates. I-V studies and
Aslamazov-Larkin analyses indicate superconductivity is inhomogeneous. The
transition can be understood in terms of a percolation model.

</DOC>
<DOC>
<DOCNO> 100562 </DOCNO>
Valleyless Sequences


  Valleyless sequences of finite length $n$ and maximum entry $k$ occur in tree
enumeration problems and provide an interesting correspondence between
permutations and compositions. In this paper we introduce the notion of \emph
{valleyless} sequences, explore the correspondence and enumerate them using the
method of generating functions.

</DOC>
<DOC>
<DOCNO> 70327 </DOCNO>
Photons from Pb-Pb Collisions at CERN SPS


  High energy photon emission rate from matter created in Pb + Pb collisions at
CERN SPS energies is evaluated. The evolution of matter from the initial state
up to freeze-out has been treated within the framework of (3+1) dimensional
hydrodynamic expansion. We observe that the photon spectra measured by the WA98
experiment are well reproduced with hard QCD photons and photons from a thermal
source with initial temperature ~ 200 MeV. The effects of the spectral changes
of hadrons with temperature on the photon emission rate and on the equation of
state are studied. Photon yield for Au + Au collisions at RHIC energies is also
estimated.

</DOC>
<DOC>
<DOCNO> 85245 </DOCNO>
The Geometrical Generating of Gravity


  This article analyzes why the energy-momentum tensors are not the source of
gravity and the dynamical variable of gravity is the affine connection instead
of the metric. We derive new gravitational equations with the dimensions of
three derivatives from the gravitational action, which has the same solution
with the Einstein equations in the vacuum. We also discuss the connection
between the new gravitational equations and the Einstein equations.

</DOC>
<DOC>
<DOCNO> 69146 </DOCNO>
Plasma Energy Loss into Kaluza-Klein Modes


  Recently, Barger {\em et al.} computed energy losses into Kaluza Klein modes
from astrophysical plasmas in the approximation of zero density for the
plasmas. We extend their work by considering the effects of finite density for
two plasmon processes. Our results show that, for fixed temperature, the energy
loss rate per cm$^3$ is constant up to some critical density and then falls
exponentially. This is true for transverse and longitudinal plasmons in both
the direct and crossed channels over a wide range of temperature and density. A
difficulty in deriving the appropriate covariant interaction energy at finite
density and temperature is addressed. We find that, for the cases considered by
Barger {\em et al.}, the zero density approximation and the neglect of other
plasmon processes is justified to better than an order of magnitude.

</DOC>
<DOC>
<DOCNO> 101273 </DOCNO>
Lattice Points inside Lattice Polytopes


  We show that, if the interior of a lattice d-polytope P contains at least one
lattice point, then it contains a lattice point whose coefficient of asymmetry
with respect to P is at most b for some number b depending on d only.
  As an application, we obtain new upper bounds on the volume of a lattice
polytope given the number of lattice points in its interior.

</DOC>
<DOC>
<DOCNO> 117549 </DOCNO>
Morphology vs. physical properties: some comments and questions


  Some of the correlations between morphological and other physical properties
of planetary nebulae (PNe) are reviewed. In particular, the finding that
bipolar (b) PNe have more massive progenitors than the other morphological
classes is discussed in detail. Earlier results are confirmed; including all
the various sources of uncertainty, the Galactic distribution of objects
indicate that b PNe are formed by stars with initial masses >1.3 solar masses,
while elliptical (e) PNe by progenitors with masses <1.3 solar masses. Recent
results for the chemical abundances of b and e PNe and their orientation within
the Galaxy are also presented. Finally, the key role in the discussion of the
formation of b PNe played by detached binary systems such as symbiotic stars is
briefly discussed.

</DOC>
<DOC>
<DOCNO> 70090 </DOCNO>
The lifetime of B_c-meson and some relevant problems


  The lifetime of the B_c-meson is estimated with consistent considerations on
all of the heavy mesons ($B^0, B^\pm, B_s, D^0, D^\pm D_s$) and the double
heavy meson B_c. In the estimate, the framework, where the non-spectator
effects for nonleptonic decays are taken into account properly, is adopted, and
the parameters needed to be fixed are treated carefully and determined by
fitting the available data. The bound-state effects in it are also considered.
We find that in decays of the meson B_c, the QCD correction terms of the
penguin diagrams and the main component terms c_1O_1, c_2O_2 of the effective
interaction Lagrangian have direct interference that causes an enhancement
about 3 ~ 4% in the total width of the B_c meson.

</DOC>
<DOC>
<DOCNO> 123079 </DOCNO>
Discovery of a Magnetic DZ White Dwarf with Zeeman-Split Lines of Heavy


  A spectroscopic survey of previously-unstudied Luyten Half Second proper
motion stars has resulted in the discoveries of two new cool magnetic white
dwarfs. One (LHS 2273) is a routine DA star, T= 6,500K, with Zeeman-split H
alpha and H beta, for which a simple model suggests a polar field strength of
18.5 MG viewed close to equator-on. However, the white dwarf LHS 2534 proves to
be the first magnetic DZ showing Zeeman-split Na I and Mg I components, as well
as Ca I and Ca II lines for which Zeeman components are blended. The Na I
splittings result in a mean surface field strength estimate of 1.92 MG. Apart
from the magnetic field, LHS 2534 is one of the most heavily-blanketed and
coolest DZ white dwarfs at T ~ 6,000K.

</DOC>
<DOC>
<DOCNO> 85413 </DOCNO>
On Cyclically Symmetrical Spacetimes


  In a recent paper Carot et al. considered the definition of cylindrical
symmetry as a specialisation of the case of axial symmetry. One of their
propositions states that if there is a second Killing vector, which together
with the one generating the axial symmetry, forms the basis of a
two-dimensional Lie algebra, then the two Killing vectors must commute, thus
generating an Abelian group. In this paper a similar result, valid under
considerably weaker assumptions, is derived: any two-dimensional Lie
transformation group which contains a one-dimensional subgroup whose orbits are
circles, must be Abelian. The method used to prove this result is extended to
apply three-dimensional Lie transformation groups. It is shown that the
existence of a one-dimensional subgroup with closed orbits restricts the
Bianchi type of the associated Lie algebra to be I, II, III, VII_0, VIII or IX.
Some results on n-dimensional Lie groups are also derived and applied to show
there are severe restrictions on the structure of the allowed four-dimensional
Lie transformation groups compatible with cyclic symmetry.

</DOC>
<DOC>
<DOCNO> 99744 </DOCNO>
Amenable actions and exactness for discrete groups


  It is proved that a discrete group G is exact if and only if its left
translation action on the Stone-Cech compactification is amenable. Combining
this with an unpublished result of Gromov, we have the existence of non exact
discrete groups.

</DOC>
<DOC>
<DOCNO> 8335 </DOCNO>
Observation of the cluster spin-glass phase in La_{2-x}Sr_{x}CuO_{4} by


  An increase of the acoustic absorption is found in La_{2-x}Sr_{x}CuO_{4} (x =
0.019, 0.03 and 0.06) close to the temperatures at which freezing of the spin
fluctuations in antiferromagnetic-correlated clusters is expected to occur. The
acoustic absorption is attributed to changes of the sizes of the quasi-frozen
clusters induced by the vibration stress through magnetoelastic coupling.

</DOC>
<DOC>
<DOCNO> 40313 </DOCNO>
Study of $\chi_{c1}$ and $\chi_{c2}$ Meson Production in B Meson Decays


  Using a sample of 9.7 million B meson pairs collected with the CLEO detector,
we study B decays to the chi_c1 and chi_c2 charmonia states, which are
reconstructed via their radiative decays to J/psi. We first measure the
branching fraction for inclusive chi_c1 production in B decays to be
Br(B->chi_c1 X)=(4.14+-0.31+-0.40)*10^-3, where the first uncertainty is
statistical and the second one is systematic. We derive the branching fractions
for direct chi_c1 and chi_c2 production in B decays by subtracting the known
contribution of the decay chain B->psi(2S)X with psi(2S)->chi_c1,2 gamma. We
obtain Br[B->chi_c1(direct) X]=(3.83+-0.31+-0.40)*10^-3. No statistically
significant signal for chi_c2 production is observed in either case. Using the
Feldman-Cousins approach, we determine the 95% confidence intervals to be [0.2,
2.0]*10^-3 for Br(B->chi_c2 X), [0.0,1.7]*10^-3 for Br[B->chi_c2(direct) X],
and [0.00,0.44] for the ratio Br[B->chi_c2(direct) X]/Br[B->chi_c1(direct) X].
We also measure the branching ratio Br[B->chi_c2(direct)
X_s]/Br[B->chi_c1(direct) X_s] for different X_s configurations by
reconstructing B decays into exclusive final states with J/psi, a photon, a
kaon, and up to four pions. For all the X_s configurations we observe a strong
chi_c1 signal yet no statistically significant chi_c2 signal. We discuss how
our results compare with theoretical predictions in different models of
charmonium production.

</DOC>
<DOC>
<DOCNO> 150421 </DOCNO>
Codimension One Branes


  We study codimension one branes, i.e. p-branes in (p+2)-dimensions, in the
superembedding approach for the cases where the worldvolume superspace is
embedded in a minimal target superspace with half supersymmetry breaking. This
singles out the cases p=1,2,3,5,9. For p=3,5,9 the superembedding geometry
naturally involves a fundamental super 2-form potential on the worldvolume
whose generalised field strength obeys a constraint deducible from considering
an open supermembrane ending on the p-brane. This constraint, together with the
embedding constraint, puts the system on-shell for p=5 but overconstrains the
9-brane in D=11 such that the Goldstone superfield is frozen. For p=3 these two
constraints give rise to an off-shell linear multiplet on the worldvolume. An
alternative formulation of this case is given in which the linear multiplet is
dualised to an off-shell scalar multiplet. Actions are constructed for both
cases and are shown to give equivalent equations of motion. After gauge fixing
a local Sp(1) symmetry associated with shifts in the Sp(1)_R Goldstone modes,
we find that the auxiliary fields in the scalar multiplet parametrise a
two-sphere. For completeness we also discuss briefly the cases p=1,2 where the
equations of motion (for off-shell multiplets) are obtained from an action
principle.

</DOC>
<DOC>
<DOCNO> 39897 </DOCNO>
Measurement of the flux of atmospheric muons with the CAPRICE94


  A new measurement of the momentum spectra of both positive and negative muons
as function of atmospheric depth was made by the balloon-borne experiment
CAPRICE94. The data were collected during ground runs in Lynn Lake on the
19-20th of July 1994 and during the balloon flight on the 8-9th of August 1994.
We present results that cover the momentum intervals 0.3-40 GeV/c for negative
muons and 0.3-2 GeV/c for positive muons, for atmospheric depths from 3.3 to
1000 g/cm**2, respectively. Good agreement is found with previous measurements
for high momenta, while at momenta below 1 GeV/c we find latitude dependent
geomagnetic effects. These measurements are important cross-checks for the
simulations carried out to calculate the atmospheric neutrino fluxes and to
understand the observed atmospheric neutrino anomaly.

</DOC>
<DOC>
<DOCNO> 8412 </DOCNO>
Applications of Chern-Simons Ward Identities to log(T\tau) Conductivity


  We reconsider the theory of the half-filled Landau level with impurities
using the Chern-Simons formulation and study Ward identities for the
Chern-Simons theory. From these we get conductivity diagrams with impurities
which obey the continuity equation. We calculate the conductivity of these
diagrams for which we obtain log(T\tau) divergent conductivity diagrams for low
temperature T. We compare our result with the experimental values of the low
temperature conductivities. Finally we calculate the conductivity for small
deviations of the magnetic field B from the value nu=1/2. In this case we get a
singularity in the conductivity.

</DOC>
<DOC>
<DOCNO> 12738 </DOCNO>
Phase diagrams of period-4 spin chains consisting of three kinds of


  We study a period-4 antiferromagnetic mixed quantum spin chain consisting of
three kinds of spins. When the ground state is singlet, the spin magnitudes in
a unit cell are arrayed as (s-t, s, s+t, s) with integer or half-odd integer s
and t (0 <= t < s). The spin Hamiltonian is mapped onto a nonlinear sigma model
(NLSM) in a previously developed method. The resultant NLSM includes only two
independent parameters originating from four exchange constants for fixed s and
t. The topological angle in the NLSM determines the gapless phase boundaries
between disordered phases in the parameter space. The phase diagrams for
various s and t shows rich structures. We systematically explain the phases in
the singlet-cluster-solid picture.

</DOC>
<DOC>
<DOCNO> 116916 </DOCNO>
Status of Superconducting RF Linac Development for APT


  This paper describes the development progress of high current superconducting
RF linacs in Los Alamos, performed to support a design of the linac for the APT
(Accelerator Production of Tritium) Project. The APT linac design includes a CW
superconducting RF high energy section, spanning an energy range of 211 to 1030
MeV, and operating at a frequency of 700 MHz with two constant beta sections
(beta of 0.64 and 0.82). In the last two years, we have progressed towards
build a cryomodule with beta of 0.64. We completed the designs of the 5 cell
superconducting cavities and the 210 kW power couplers. We are scheduled to
begin assembly of the cryomodule in September 2000. In this paper, we present
an overview of the status of our development efforts and a report on the
results of the cavity and coupler test program.

</DOC>
<DOC>
<DOCNO> 13278 </DOCNO>
Coupled Bose-Einstein condensate: Collapse for attractive interaction


  We study the collapse in a coupled Bose-Einstein condensate of two types of
bosons 1 and 2 under the action of a trap using the time-dependent
Gross-Pitaevskii equation. The system may undergo collapse when one, two or
three of the scattering lengths $a_{ij}$ for scattering of boson $i$ with $j$,
$i,j = 1, 2 $, are negative representing an attractive interaction. Depending
on the parameters of the problem a single or both components of the condensate
may experience collapse.

</DOC>
<DOC>
<DOCNO> 178614 </DOCNO>
The role of three-body collisions in phi-meson production processes near


  The amplitude of subthreshold phi-meson production is calculated using
dominant tree-level diagrams for three-body collisions. It is shown that the
production can overwhelmingly be described by two-step processes. The effect of
the genuine three-body contribution (i.e. the contribution which cannot be
factorized) is discussed. The production rate of phi-mesons is presented for
proton induced reactions on carbon.

</DOC>
<DOC>
<DOCNO> 10422 </DOCNO>
Field-dependence of the Magnetic Relaxation in Mn12-Acetate: A New Form


  We report point by point measurements below the blocking temperature of the
magnetic relaxation of Mn$_{12}$-acetate as a function of magnetic field
applied along the easy axis of magnetization. Unexpectedly complex structure is
observed which we attribute to the effect of higher-order terms of the spin
Hamiltonianon on the tunneling process.

</DOC>
<DOC>
<DOCNO> 121559 </DOCNO>
Neutral and ionized gas distribution in and around the radio galaxy Coma


  HI absorption has been detected with the WSRT against both lobes of the radio
galaxy Coma A. This radio galaxy could be expanding in a particularly gas rich
environment, perhaps the result from interactions/mergers between the dominant
giant galaxy (associated with the radio galaxy) and less massive galaxies in
the same group.

</DOC>
<DOC>
<DOCNO> 117105 </DOCNO>
Non-destructive spatial heterodyne imaging of cold atoms


  We demonstrate a new method for non-destructive imaging of laser-cooled
atoms. This spatial heterodyne technique forms a phase image by interfering a
strong carrier laser beam with a weak probe beam that passes through the cold
atom cloud. The figure of merit equals or exceeds that of phase-contrast
imaging, and the technique can be used over a wider range of spatial scales. We
show images of a dark spot MOT taken with imaging fluences as low as 61 pJ/cm^2
at a detuning of 11 linewidths, resulting in 0.0004 photons scattered per atom.

</DOC>
<DOC>
<DOCNO> 84318 </DOCNO>
The Reeh-Schlieder Property for Quantum Fields on Stationary Spacetimes


  We show that as soon as a linear quantum field on a stationary spacetime
satisfies a certain type of hyperbolic equation, the (quasifree) ground- and
KMS-states with respect to the canonical time flow have the Reeh-Schlieder
property. We also obtain an analog of Borchers' timelike tube theorem. The
class of fields we consider contains the Dirac field, the Klein-Gordon field
and the Proca field.

</DOC>
<DOC>
<DOCNO> 69180 </DOCNO>
B_c - meson sum rules at next-to-leading order


  We present B_c-meson two-point sum rules at next-to-leading order in NRQCD
approximation. Analitycal results for perturbative spectral density and gluon
condensate contribution with account for summed Coulomb corrections are given.
Estimates of various c-quark masses together with couplings and masses of
lowest lying B_c-meson resonances are performed.

</DOC>
<DOC>
<DOCNO> 121654 </DOCNO>
Optical and Infrared Colors of Stars Observed by 2MASS and SDSS


  We discuss optical and infrared photometric properties of stars matched in
the Two Micron All Sky Survey (2MASS) and the Sloan Digital Sky Survey (SDSS)
commissioning data for 50 deg2 of sky. About 98% (63,000) of objects listed in
the 2MASS Point Source Catalog in the analyzed area are matched within 2 arcsec
to an SDSS source. The matched sources represent 8% of the about 800,000 SDSS
sources in this area, and 15% of them are resolved in SDSS imaging data,
although they are detected as point sources in 2MASS data.
  For about 14,000 stars with the smallest photometric errors (< 10%) in both
surveys, we present optical and infrared color-magnitude and color-color
diagrams. We use optical (SDSS) colors to identify the stellar spectral
sequence and show that stars of different spectral types can have similar
infrared colors, thus making the classification of stars based on only 2MASS
data very difficult. However, a broad separation into ``early'' and ``late''
spectral types (relative to type K0) is possible with a reliability of about
95% even with 2MASS colors alone.
  The distributions of matched sources in color-magnitude and color-color
diagrams are compared to the predictions of a stellar population synthesis
code. We find that the models are in fair overall agreement with the data. The
most significant discrepancies are found for the number ratio of ``early'' to
``late'' type stars (by about a factor of 2) and in the colors of M stars (up
to 0.2 mag).

</DOC>
<DOC>
<DOCNO> 101540 </DOCNO>
Complex bounds for multimodal maps: bounded combinatorics


  We proved the so called complex bounds for multimodal, infinitely
renormalizable analytic maps with bounded combinatorics: deep renormalizations
have polynomial-like extensions with definite modulus. The complex bounds is
the first step to extend the renormalization theory of unimodal maps to
multimodal maps.

</DOC>
<DOC>
<DOCNO> 117153 </DOCNO>
An Optical Trap for Collisional Studies on Cold Fermionic Potassium


  We report on trapping of fermionic 40K atoms in a red-detuned standing-wave
optical trap, loaded from a magneto-optical trap. Typically, 10^6 atoms are
loaded at a density of 10^12 cm^-3 and a temperature of 65 microK, and trapped
for more than 1 s. The optical trap appears to be the proper environment for
performing collisional measurements on the cold atomic sample. In particular we
measure the elastic collisional rate by detecting the rethermalization
following an intentional parametric heating of the atomic sample. We also
measure the inelastic two-body collisional rates for unpolarized atoms in the
ground hyperfine states, through detection of trap losses.

</DOC>
<DOC>
<DOCNO> 10606 </DOCNO>
Observability of quantum phase fluctuations in cuprate superconductors


  We study the order parameter phase fluctuation effects in cuprate
superconductors near T=0, using a quasi-two-dimensional d-wave BCS model. An
effective phason theory is obtained which is used to estimate the strength of
the fluctuations, the fluctuation correction to the in-plane penetration depth,
and the pair-field susceptibility. We find that while the phase fluctuation
effects are difficult to observe in the renormalization of the superfluid phase
stiffness, they may be observed in a pair tunneling experiment which measures
the pair-field susceptibility.

</DOC>
<DOC>
<DOCNO> 102104 </DOCNO>
Co-Amenability of compact quantum groups


  We study the concept of co-amenability for a compact quantum group. Several
conditions are derived that are shown to be equivalent to it. Some consequences
of co-amenability that we obtain are faithfulness of the Haar integral and
automatic norm-boundedness of positive linear functionals on the quantum
group's Hopf *-algebra (neither of these properties necessarily holds without
co-amenability).

</DOC>
<DOC>
<DOCNO> 11442 </DOCNO>
Predictions about the behaviour of diamond, silicon, SiC and some AIIIBV


  The utilisation of crystalline semiconductor materials as detectors and
devices operating in high radiation environments, at the future particle
colliders, in space applications, in medicine and industry, makes necessary to
obtain radiation harder materials. Diamond, SiC and different AIIIBV compounds
(GaAs, GaP, InP, InAs, InSb) are possible competitors for silicon to different
electronic devices for the up-mentioned applications. The main goal of this
paper is to give theoretical predictions about the behaviour of these
semiconductors in hadron fields (pions, protons). The effects of the
interaction between the incident particle and the semiconductor are
characterised in the present paper both from the point of view of the
projectile, the relevant quantity being the energy loss by nuclear
interactions, and of the target, using the concentration of primary radiation
induced defects on unit particle fluence. Some predictions about the damage
induced by hadrons in these materials in possible applications in particle
physics and space experiments are done.

</DOC>
<DOC>
<DOCNO> 71759 </DOCNO>
Periodic Theta Vacuum Model and the QCD Instanton Vacuum


  We formulate a toy model for the $\theta$ vacuum that embodies the n-point
moments of the even and odd topological charge densities. The partition
function is $2\pi$ periodic only after resumming over all winding modes. We
apply the same analysis to the quenched instanton vacuum at finite $\theta$ and
derive saddle-point results for the vacuum energy density that are manifestly
$2\pi$ periodic whatever $\theta$. We briefly discuss the consequences of
unquenching the fermions on our results.

</DOC>
<DOC>
<DOCNO> 152428 </DOCNO>
Factorization and generalized *-products


  The generalized *-products, or the $*_N$-products, appear both in the
one-loop effective action of noncommutative Yang-Mills theories and in the
coupling of a closed string to N open strings on a disk when the D-brane
world-volume is noncommutative. Factorization of the string amplitudes provides
a uniform understanding of the $*_N$-products and a hint to obtain a simple,
explicit formula (in the momentum space) for arbitrary N in the non-Abelian
case. Possible extension to a more general ${}_M *_{N}$-product in the M-loop
context is discussed.

</DOC>
<DOC>
<DOCNO> 100689 </DOCNO>
Invariant measures for Burgers equation with stochastic forcing


  In this paper we study the following Burgers equation
  du/dt + d/dx (u^2/2) = epsilon d^2u/dx^2 + f(x,t)
  where f(x,t)=dF/dx(x,t) is a random forcing function, which is periodic in
x and white noise in t.  We prove the existence and uniqueness of an
invariant measure by establishing a ``one force, one solution'' principle,
namely that for almost every realization of the force, there is a unique
distinguished solution that exists for the time interval (-infty, +infty)
and this solution attracts all other solutions with the same forcing.
This is done by studying the so-called one-sided minimizers.  We also
give a detailed description of the structure and regularity properties
for the stationary solutions.  In particular, we prove, under some
non-degeneracy conditions on the forcing, that almost surely there is
a unique main shock and a unique global minimizer for the stationary
solutions.  Furthermore the global minimizer is a hyperbolic trajectory
of the underlying system of characteristics.

</DOC>
<DOC>
<DOCNO> 9862 </DOCNO>
Tunneling Dynamics of Bose-Einstein Condensates with Feshbach Resonances


  We study tunneling dynamics of atomic pairs in Bose-Einstein condensates with
Feshbach resonances. It is shown that the tunneling of the atomic pairs depends
on not only the tunneling coupling between the atomic condensate and the
molecular condensate, but also the inter-atomic nonlinear interactions and the
initial number of atoms in these condensates. It is found that in addition to
oscillating tunneling current between the atomic condensate and the molecular
condensate, the nonlinear atomic-pair tunneling dynamics sustains a self-locked
population imbalance: macroscopic quantum self-trapping effect. Influence of
decoherence induced by non-condensate atoms on tunneling dynamics is
investigated. It is shown that decoherence suppresses atomic-pair tunneling.

</DOC>
<DOC>
<DOCNO> 69692 </DOCNO>
Determining the Spin Structure of the Photon at Future Colliders


  It is demonstrated that measurements of the spin asymmetry for di-jet
production at future polarized colliders appear to be particularly suited for a
first determination of the so far unmeasured parton densities of circularly
polarized photons.

</DOC>
<DOC>
<DOCNO> 123019 </DOCNO>
The Cosmic Background Imager


  The Cosmic Background Imager (CBI) is an instrument designed to make images
of the cosmic microwave background radiation and to measure its statistical
properties on angular scales from about 3 arc minutes to one degree (spherical
harmonic scales from l ~ 4250 down to l ~ 400). The CBI is a 13-element
interferometer mounted on a 6 meter platform operating in ten 1-GHz frequency
bands from 26 GHz to 36 GHz. The instantaneous field of view of the instrument
is 45 arcmin (FWHM) and its resolution ranges from 3 to 10 arcmin; larger
fields can be imaged by mosaicing. At this frequency and resolution, the
primary foreground is due to discrete extragalactic sources, which are
monitored at the Owens Valley Radio Observatory and subtracted from the CBI
visibility measurements. The instrument has been making observations since late
1999 of both primordial CMB fluctuations and the Sunyaev-Zeldovich effect in
clusters of galaxies from its site at an altitude of 5080 meters near San Pedro
de Atacama, in northern Chile. Observations will continue until August 2001 or
later. We present preliminary results from the first few months of
observations.

</DOC>
<DOC>
<DOCNO> 151283 </DOCNO>
Aspects of the free field description of string theory on AdS_3


  The near boundary limit of string theory in AdS_3 is analysed using the
Wakimoto free field representation of SL(2,R). The theory is considered as a
direct product of the SL(2,R)/U(1) coset and a free boson. Correlation
functions are constructed generalizing to the non-compact case the integral
representation of conformal blocks introduced by Dotsenko in the compact SU(2)
CFT. Sectors of the theory obtained by spectral flow manifestly appear. The
formalism naturally leads to consider scattering processes violating winding
number conservation. The consistency of the procedure is verified in the
factorization limit.

</DOC>
<DOC>
<DOCNO> 121349 </DOCNO>
Deep Near Infrared Photometry of New Galactic Globular Clusters


  We present a preliminary report on the first deep infrared photometry of
2MASS GC01 and 2MASS GC02 (GC01 and GC02 hereafter) - new Galactic globular
cluster (GC) candidates, discovered by the 2MASS. They both appear to be
genuine disk GCs though highly obscured. The location of the two GCs suggests
that they are metal rich - [Fe/H]~-0.5. We estimated their distance and
reddening using the K_s-band brightness of the red giant branch (RGB) bump, and
J-K_s color of the RGB at M_K=-3 mag: D=3.1+/-0.5, 3.9+/-0.6 kpc, and
A_V=20.9+/-0.7, 17.2+/-1.2 mag, for GC01 and GC02 respectively. Variation in
the metal abundance can change our results within 30-35%.

</DOC>
<DOC>
<DOCNO> 152619 </DOCNO>
On S-duality in (2+1)-Chern-Simons Supergravity


  Strong/weak coupling duality in Chern-Simons supergravity is studied. It is
argued that this duality can be regarded as an example of superduality. The use
of supergroup techniques for the description of Chern-Simons supergravity
greatly facilitates the analysis.

</DOC>
<DOC>
<DOCNO> 68894 </DOCNO>
Nucleon strangeness as the response to a strangeness-sensitive probe in


  On top of its valence quarks, the full nucleon ground state may contain
appreciable admixture of s-\bar{s} pairs already at small momentum transfers.
This paper discusses strangeness in the mean-field type of nucleon models, and
exemplifies this by explicit calculations in the MIT bag model enriched by the
presence of instantons.
  We calculate the instanton contribution to the strangeness in the MIT bag (on
top of the standard contribution to strangeness found in that model). Although
we do it in an essentially perturbative way, we present a detailed derivation
of the formula expressing nucleon matrix elements of bilinear strange quark
operators, in terms of a model valence nucleon state and interactions producing
quark-antiquark fluctuations on top of that valence state. We do it in detail
to clarify our argument that in the context of the mean-field type of quark
models (where a Fock state expansion exists and where the nucleon state can be
constructed out of single-quark states), the resulting formula acquires a
significance beyond perturbation theory.The derivation combines the usage of
the evolution operator containing a strangeness source, and Feynman-Hellmann
theorem.

</DOC>
<DOC>
<DOCNO> 99981 </DOCNO>
Composition sum identities related to the distribution of coordinate


  Utilizing spectral residues of parameterized, recursively defined sequences,
we develop a general method for generating identities of composition sums.
Specific results are obtained by focusing on coefficient sequences of solutions
of first and second order, ordinary, linear differential equations. Regarding
the first class, the corresponding identities amount to a proof of the
exponential formula of labelled counting. The identities in the second class
can be used to establish certain geometric properties of the simplex of
bounded, ordered, integer tuples. We present three theorems that support the
conclusion that the inner dimensions of such an order simplex are, in a certain
sense, more ample than the outer dimensions. As well, we give an algebraic
proof of a bijection between two families of subsets in the order simplex, and
inquire as to the possibility of establishing this bijection by combinatorial,
rather than by algebraic methods.

</DOC>
<DOC>
<DOCNO> 150621 </DOCNO>
Regular BPS black holes: macroscopic and microscopic description of the


  In this paper we construct the BPS black hole generating solution of
toroidally compactified string (and M) theory, giving for it both the
macroscopic and microscopic description. Choosing a proper U-duality gauge the
latter will be given by a bound state made solely of D-branes. The axionic
nature of the supergravity solution will be directly related to non-trivial
angles between the constituent D-branes (type IIB configuration) or, in a
T-dual gauge, to the presence of magnetic flux on constituent D-brane world
volumes (type IIA configuration). As expected, the four dimensional axion
fields arise from the dimensional reduction of non-diagonal metric tensor
components or Kalb-Ramond B field components for type IIB or type IIA cases,
respectively. Thanks to this result it is then now possible to fill the full
56-dimensional U-duality orbit of N=8 BPS black holes and to have a macroscopic
and microscopic description of all of them.

</DOC>
<DOC>
<DOCNO> 80980 </DOCNO>
On the short distance nonperturbative corrections in heavy quark


  We study the corrections due to renormalons to the heavy hadron decay
width.The renormalons contribution estimated in terms of finite gluon mass
based on the assumption that the gluon mass represents the short distance
nonperturbative effects in the standard OPE (and hence in the heavy quark
expansion). We found that the corrections are about 10% of the leading decay
rate. We point out the implications for the assumption of quark-hadron duality
in heavy quark expansion.

</DOC>
<DOC>
<DOCNO> 68190 </DOCNO>
Explicit SO(10) Supersymmetric Grand Unified Model for the Higgs and


  A complete set of fermion and Higgs superfields is introduced with
well-defined SO(10) properties and U(1) x Z_2 x Z_2 family charges from which
the Higgs and Yukawa superpotentials are constructed. The structures derived
for the four Dirac fermion and right-handed Majorana neutrino mass matrices
coincide with those previously obtained from an effective operator approach.
Ten mass matrix input parameters accurately yield the twenty masses and mixings
of the quarks and leptons with the bimaximal atmospheric and solar neutrino
vacuum solutions favored in this simplest version.

</DOC>
<DOC>
<DOCNO> 120767 </DOCNO>
Evolution of highly buoyant thermals in a stratified layer


  The buoyant rise of thermals (i.e. bubbles of enhanced entropy, but initially
in pressure equilibrium) is investigated numerically in three dimensions for
the case of an adiabatically stratified layer covering 6-9 pressure scale
heights. It is found that these bubbles can travel to large heights before
being braked by the excess pressure that builds up in order to drive the gas
sideways in the head of the bubble. Until this happens, the momentum of the
bubble grows as described by the time-integrated buoyancy force. This validates
the simple theory of bubble dynamics whereby the mass entrainment of the bubble
provides an effective braking force well before the bubble stops ascending.
This is quantified by an entrainment parameter alpha which is calculated from
the simulations and is found to be in good agreement with the experimental
measurements. This work is discussed in the context of contact binaries whose
secondaries could be subject to dissipative heating in the outermost layers.

</DOC>
<DOC>
<DOCNO> 7704 </DOCNO>
Transport properties and point contact spectra of Ni_xNb_{1-x} metallic


  Bulk resistivity and point contact spectra of Ni_xNb_{1-x} metallic glasses
have been investigated as functions of temperature (0.3-300K) and magnetic
field (0-12T). Metallic glasses in this family undergo a superconducting phase
transition determined by the Nb concentration. When superconductivity was
suppressed by a strong magnetic field, both the bulk sample R(T) and the point
contact differential resistance curves of Ni_xNb_{1-x} showed logarithmic
behavior at low energies, which is explained by a strong electron - "two level
system" coupling. We studied the temperature, magnetic field and contact
resistance dependence of Ni_{44}Nb_{56} point-contact spectra in the
superconducting state and found telegraph-like fluctuations superimposed on
superconducting characteristics. These R(V) characteristics are extremely
sensitive detectors for slow relaxing "two level system" motion.

</DOC>
<DOC>
<DOCNO> 120632 </DOCNO>
An optical and X-ray study of the peculiar narrow-line quasar QSO


  We present an optical and X-ray study of the quasar QSO 0117-2837. It
exhibits an interesting combination of optical and X-ray properties: Despite
its extremely steep observed X-ray spectrum (Gamma_x ~ -4 when fit by a simple
powerlaw), its Balmer lines are fairly broad. A two-component Gaussian fit to
H_beta yields FWHM_{Hbeta, broad} ~ 4000 km/s, and places QSO 0117-2837 in the
`zone of avoidance' in the FWHM_{Hbeta}-Gamma_x diagram.
   A time variability analysis shows that QSO 0117-2837 is another case of
Narrow-line Sy1 galaxy (NLSy1 hereafter) which does not show any X-ray
variability during the observation.
   The results are discussed in view of the NLSy1 character of QSO 0117-2837.

</DOC>
<DOC>
<DOCNO> 40588 </DOCNO>
Standard Model Matrix Elements for Neutral B-Meson Mixing and Associated


  We present results of quenched lattice calculations of the matrix elements
relevant for B_d-\bar B_d and B_s-\bar B_s mixing in the Standard Model.
Results for the corresponding SU(3)-breaking ratios, which can be used to
constrain or determine |V_{td}|, are also given. The calculations are performed
at two values of the lattice spacing, corresponding to \beta = 6.0 and \beta =
6.2, with quarks described by a mean-field-improved Sheikholeslami-Wohlert
action. As a by-product, we obtain the leptonic decay constants of B and D
mesons. We also present matrix elements relevant for D^0-\bar D^0 mixing. Our
results are summarized in the Introduction.

</DOC>
<DOC>
<DOCNO> 9083 </DOCNO>
Complex Entropic Forms for Gradient Pattern Analysis of Spatio-temporal


  In this paper we describe two new computational operators, called complex
entropic form (CEF) and generalized complex entropic form (GEF), for pattern
characterization of spatially extended systems. Besides of being a measure of
regularity, both operators permit to quantify the degree of phase disorder
associated with a given gradient field. An application of CEF and GEF to the
analysis of the gradient pattern dynamics of a logistic Coupled Map Lattice is
presented. Simulations using a Gaussian and random initial condition, provide
interesting insights on the the system gradual transition from order/symmetry
to disorder/randomness.

</DOC>
<DOC>
<DOCNO> 40492 </DOCNO>
Jet energy scale setting with "photon+Jet" events at LHC energies. Event


  In this paper the study of "photon+Jet" events is continued, aimed at jet
energy scale setting and hadron calorimeter calibration at LHC energies. The
event number distribution over Pt and pseudorapidity eta in the barrel region
of the photon is presented. The features of "photon+Jet" events in CMS detector
|eta|<1.4 are exposed. Pt structure of the region in the eta-phi space inside
and beyond jet is also shown.

</DOC>
<DOC>
<DOCNO> 99749 </DOCNO>
Existence of close pseudoholomorphic disks for almost complex manifolds


  In this paper we extend the notion of the Kobayashi-Royden pseudonorm for
almost complex manifolds. Its basic properties known from the complex analysis
are preserved in the nonintegrable case as well. The main theorem on
coincidence of the pseudodistance induced by this pseudonorm with the Kobayashi
pseudodistance for the almost complex manifold is equivalent to the possibility
of deforming slightly a pseudoholomorphic disk in an almost complex manifold.
We also describe the result in terms of h-principle and consider a geometric
application for moduli spaces of pseudoholomorphic curves.

</DOC>
<DOC>
<DOCNO> 121147 </DOCNO>
Very Large Telescope Observations of the peculiar globular cluster


  We present results from multi-band observations in the central region of the
cluster NGC6712 with the ESO-Very Large Telescope. Using high resolution images
we have identified three UV-excess stars. In particular two of them are within
the cluster core, a few arcsec apart: the first object is star "S" which
previous studies identified as the best candidate to the optical counterpart to
the luminous X-ray source detected in this cluster. The other UV object shows
clearcut H-alpha emission and, for this reason, is an additional promising
interacting binary candidate (a quiescent LMXB or a CV). The presence of two
unrelated interacting binary systems a few arcsec apart in the core of this
low-density cluster is somewhat surprising and supports the hypothesis that the
(internal) dynamical history of the cluster and/or the (external) interaction
with the Galaxy might play a fundamental role in the formation of these
peculiar objects.

</DOC>
<DOC>
<DOCNO> 151442 </DOCNO>
Quantum Space-Time and Reference Frames in Gravity and Flat Space-Time


  The quantum space-time model which accounts material Reference Frames (RF)
quantum effects considered for flat space-time and ADM canonical gravity. As
was shown by Aharonov for RF - free material object its c.m. nonrelativistic
motion in vacuum described by Schrodinger wave packet evolution which modify
space coordinate operator of test particle in this RF and changes its
Heisenberg uncertainty relations. In the relativistic case we show that Lorentz
transformations between two RFs include the quantum corrections for RFs
momentum uncertainty and in general can be formulated as the quantum space-time
transformations. As the result for moving RF its Lorentz time boost acquires
quantum fluctuations which calculated solving relativistic Heisenberg equations
for the quantum clocks models. It permits to calculate RF proper time for the
arbitrary RF quantum motion including quantum gravity metrics fluctuations.
Space-time structure of canonical Quantum Gravity and its observables evolution
for RF proper time discussed in this quantum space-time transformations
framework.

</DOC>
<DOC>
<DOCNO> 117069 </DOCNO>
Design of the JLC/NLC RDDS Structure Using Parallel Eigensolver Omega3p


  The complexity of the Round Damped Detuned Structue (RDDS) for the JLC/NLC
main linac is driven by the considerations of rf efficiency and dipole
wakefield suppression. As a time and cost saving measure for the JLC/NLC, the
dimensions of the 3D RDDS cell are being determined through computer modeling
to within fabrication precision so that no tuning may be needed once the
structures are assembled. The tolerances on the frequency errors for the RDDS
structure are about one MHz for the fundamental mode and a few MHz for the
dipole modes. At the X-band frequency, these correspond to errors of a micron
level on the major cell dimensions. Such a level of resolution requires highly
accurate field solvers and vast amount of computer resources. A parallel
finite-element eigensolver Omega3P was developed at SLAC that runs on massively
parallel computers such as the Cray T3E at NERSC. The code was applied in the
design of the RDDS cell dimensions that are accurate to within fabrication
precision. We will present the numerical approach of using these codes to
determine the RDDS dimensions and compare the numerical predictions with the
cold test measurements on RDDS prototypes that are diamond-turned using these
dimensions.

</DOC>
<DOC>
<DOCNO> 123324 </DOCNO>
Java-Applet For Radio Spectra Analysis


  New services for Clusters of Galaxies Database created in the Astronomical
Institute of SPbU have been constructed. The detailed description of database
and its content is available at http://www.astro.spbu.ru/CLUSTERS/. The
information contained in the database can be used for solution of the specific
astronomical problems. One of these problems is the researches of radio
emission spectra of clusters' objects. The researches can give help in solution
of the problems of origin and evolution of extragalactic radio sources. Spectra
of radio galaxies contain important information about radio power in the
processes responsible for their activity. This report presents the software for
the database that provides work with radio spectra of extragalactic sources.
This client-application has been released as the Java-applet and thus provides
a Web based interface that is supported on many operating systems. The
facilities of the applet such as approximations of spectra measurement points
and calculation of spectral parameters are illustrated in the report. Also we
demonstrate new version of the application that realized on Java2 and gave
access to additional functions such as printing.

</DOC>
<DOC>
<DOCNO> 69905 </DOCNO>
Laser Cooling of TeV Muons


  We show that Compton scattering can be used to cool TeV-scale muon beams, and
we derive analytical expressions for the equilibrium transverse angular spread,
longitudinal energy spread, and power requirements. We find that a factor of a
few thousand reduction in emittance is possible for a 3 TeV muon collider.

</DOC>
<DOC>
<DOCNO> 11650 </DOCNO>
Nanoelectromechanical Systems


  Nanoelectromechanical systems, or NEMS, are MEMS scaled to submicron
dimensions. In this size regime, it is possible to attain extremely high
fundamental frequencies while simultaneously preserving very high mechanical
responsivity (small force constants). This powerful combination of attributes
translates directly into high force sensitivity, operability at ultralow power,
and the ability to induce usable nonlinearity with quite modest control forces.
In this overview I shall provide an introduction to NEMS and will outline
several of their exciting initial applications. However, a stiff entry fee
exists at the threshold to this new domain: new engineering is crucial to
realizing the full potential of NEMS. Certain mainstays in the methodology of
MEMS will, simply, not scale usefully into the regime of NEMS. The most
problematic of issues are the size of the devices compared to their embedding
circuitry, their extreme surface-to-volume ratios, and their unconventional
"characteristic range of operation". These give rise to some of the principal
current challenges in developing NEMS. Most prominent among these are the need
for: ultrasensitive, very high bandwidth displacement transducers; an
unprecedented control of surface quality and adsorbates; novel modes of
efficient actuation at the nanoscale, and precise, robust, and routinely
reproducible new approaches to surface and bulk nanomachining. I survey each of
these aspects in turn, and conclude by describing several of the exciting
prospects in this new field.

</DOC>
<DOC>
<DOCNO> 40316 </DOCNO>
Recent Results from the BNL E787 Experiment


  Recent results from a rare kaon decay experiment E787 at the BNL-AGS on K^+
\to \pi^+ \nu \bar\nu, K^+ \to \mu^+ \nu \gamma, and K^+ \to \pi^+ \pi^0 \gamma
decays are reported.

</DOC>
<DOC>
<DOCNO> 169814 </DOCNO>
Casimir and van der Waals force between two plates or a sphere (lens)


  The Casimir and van der Waals forces acting between two metallic plates or a
sphere (lens) above a plate are calculated accounting for the finite
conductivity of the metals. The simple formalism of surface modes is briefly
presented which allows the possibility to obtain the generalization of Lifshitz
results for the case of two semi-spaces covered by the thin layers. Additional
clarifications of the regularization procedure provides the means to obtain
reliable results not only for the force but also for the energy density. This,
in turn, leads to the value of the force for the configuration of a sphere
(lens) above a plate both of which are covered by additional layers. The
Casimir interaction between Al and Au test bodies is recalculated using the
optical tabulated data for the complex refractive index of these metals. The
computations turn out to be in agreement with the perturbation theory up to the
fourth order in relative penetration depth of electromagnetic zero point
oscillations into the metal. The disagreements between the results recently
presented in the literature are resolved. The Casimir force between Al bodies
covered by the thin Au layers is computed and the possibility to neglect
spatial dispersion effects is discussed as a function the layer thickness. The
van der Waals force is calculated including the transition region to the
Casimir force. The pure non-retarded van der Waals force law between Al and Au
bodies is shown to be restricted to a very narrow distance interval from 0.5 nm
to (2--4) nm. New, more exact, values of the Hamaker constant for Al and Au are
determined.

</DOC>
<DOC>
<DOCNO> 68477 </DOCNO>
The pion charge radius from charged pion electroproduction


  We analyze a low-energy theorem of threshold pion electroproduction which
allows one to determine the charge radius of the pion. We show that at the same
order where the radius appears, pion loops induce a correction to the momentum
dependence of the longitudinal dipole amplitude $L_{0+}^{(-)}$. This
model-independent correction amounts to an increase of the pion charge radius
squared from the electroproduction data by about 0.26~fm$^2$. It sheds light on
the apparent discrepancy between the recent determination of the pion radius
from electroproduction data and the one based on pion-electron scattering.

</DOC>
<DOC>
<DOCNO> 101559 </DOCNO>
Combinatorics of the $\hat{sl_2}$ spaces of coinvariants II


  The spaces of coinvariants are quotient spaces of integrable $\hat{sl_2}$
modules by subspaces generated by actions of certain subalgebras labeled by a
set of points on a complex line. When all the points are distinct, the spaces
of coinvariants essentially coincide with the spaces of conformal blocks in the
WZW conformal field theory and their dimensions are given by the Verlinde rule.
  We describe monomial bases for the $\wsl$ spaces of coinvariants, In
particular, we prove that the spaces of coinvariants have the same dimensions
when all the points coincide. We establish recursive relations satisfied by the
monomial bases and the corresponding characters of the spaces of coinvariants.
For the proof we use filtrations of the $\hat{\mathfrak{sl}}_2$ modules, and
further filtrations on the adjoint graded spaces for the first filtrations.
  This paper is the continuation of [FKLMM].

</DOC>
<DOC>
<DOCNO> 100384 </DOCNO>
Global well-posedness below energy space for the 1D Zakharov system


  The Cauchy problem for the 1-dimensional Zakharov system is shown to be
globally well-posed for large data which not necessarily have finite energy.
The proof combines the local well-posedness result of Ginibre, Tsutsumi, Velo
and a general method introduced by Bourgain to prove a similar result for
nonlinear Schr\"odinger equations.

</DOC>
<DOC>
<DOCNO> 12809 </DOCNO>
Predicting and generating time series by neural networks: An


  An overview is given about the statistical physics of neural networks
generating and analysing time series. Storage capacity, bit and sequence
generation, prediction error, antipredictable sequences, interacting
perceptrons and the application on the minority game are discussed. Finally, as
a demonstration a perceptron predicts bit sequences produced by human beings.

</DOC>
<DOC>
<DOCNO> 85225 </DOCNO>
Positivity of the Bondi Energy in Einstein-Maxwell Axion- Dilaton


  We present a proof of the positivity of the Bondi energy in Einstein-Maxwell
axion-dilaton gravity, being the low-energy limit of the heterotic string
theory. We consider the spacelike hypersurface which asymptotically approaches
a null cone and on which the equations of the theory under consideration are
given. Next, we generalize the proof allowing the hypersurface having inner
boundaries.

</DOC>
<DOC>
<DOCNO> 72334 </DOCNO>
Evolution of Black Holes in Brans-Dicke Cosmology


  We consider a modified ``Swiss cheese'' model in the Brans-Dicke theory, and
discuss the evolution of black holes in the expanding universe. We define the
black hole radius by the Misner-Sharp mass and find the time evolution for dust
and vacuum universes.

</DOC>
<DOC>
<DOCNO> 121340 </DOCNO>
A Possible Evolutionary Connection between AGN and Starburst in LINERs


  Our analysis on the two magnitude-limited samples of LINERs suggests a
correlation between $L_{\FIR}/L_{\B}$ or f(25\micron)/f(60\micron), and
Hubble-type index at $>$99.99% significance level. As $L_{\FIR}/L_{\B}$ and
f(25\micron)/f(60\micron) are considered as the indicators of star-formation
activity and AGN activity, respectively, our result suggests that LINERs with
higher AGN activity may have a lower star-formation contribution. The ones with
highest AGN activity and lowest star-formation contributions are ellipticals.
All well-studied LINER 1s belong to this group. On the other hand, LINERs with
higher star-formation activity present lower AGN contributions. We find all
well-studied LINER 2s in this parameter space. Most of LINERs having inner ring
structures belong to this group. Statistics with other indicators of
star-formation or AGN activity (nulear mass-to-light ratio at H band, and the
ratio of X-ray-to-UV power) provide further evidence for such a trend. We have
seen that along with the evolution of galaxies from late-type spirals to
early-type ones, and up to ellipticals, the intensity of AGN activity increases
with decreasing star-formation contributions, The above analyses may suggest a
possible connection between the host galaxies and nuclear activities, and it
might also indicate a possible evolutionary connection between AGN and
starburst in LINERs.

</DOC>
<DOC>
<DOCNO> 71961 </DOCNO>
An explanation of the "negative neutrino mass squared" anomaly in


  A proposed solution of the anomalous behavior of the electron spectrum near
the endpoint of tritium $\beta$-decay is offered. It is based on a new theory
of mass in which mass becomes a dynamical variable, and the electron in the
tritium $\beta$-decay has a narrow mass distribution. The predicted Kurie plots
explain the main feature (``$m_{\nu}^2 < 0 $'') of this anomalous behavior.

</DOC>
<DOC>
<DOCNO> 151970 </DOCNO>
Solitonic sectors, conformal boundary conditions and three-dimensional


  The correlation functions of a two-dimensional rational conformal field
theory, for an arbitrary number of bulk and boundary fields and arbitrary world
sheets can be expressed in terms of Wilson graphs in appropriate
three-manifolds. We present a systematic approach to boundary conditions that
break bulk symmetries. It is based on the construction, by `alpha-induction',
of a fusion ring for the boundary fields. Its structure constants are the
annulus coefficients and its 6j-symbols give the OPE of boundary fields.
Symmetry breaking boundary conditions correspond to solitonic sectors.

</DOC>
<DOC>
<DOCNO> 121106 </DOCNO>
Snapshot Identification of Gamma Ray Burst Optical Afterglows


  Gamma ray burst afterglows can be identified in single epoch observations
using three or more optical filters. This method relies on color measurements
to distinguish the power law spectrum of an afterglow from the curved spectra
of stars. Observations in a fourth filter will further distinguish between
afterglows and most galaxies up to redshifts z ~ 1. Many afterglows can also be
identified with fewer filters using ultraviolet excess, infrared excess, or
Lyman break techniques. By allowing faster identification of gamma ray burst
afterglows, these color methods will increase the fraction of bursts for which
optical spectroscopy and other narrow-field observations can be obtained.
Because quasar colors can match those of afterglows, the maximum error box size
where an unambiguous identification can be expected is set by the flux limit of
the afterglow search and the quasar number-flux relation. For currently typical
error boxes (10 -- 100 square arcminutes), little contamination is expected at
magnitudes R < 21.5 +- 0.5. Archival data demonstrates that the afterglow of
GRB 000301C could have been identified using this method. In addition to
finding gamma ray burst counterparts, this method will have applications in
``orphan afterglow'' searches used to constrain gamma ray burst collimation.

</DOC>
<DOC>
<DOCNO> 11988 </DOCNO>
Non-magnetic impurities as probes of insulating and doped Mott


  We characterize paramagnetic Mott insulators by their response to static,
non-magnetic impurities. States with spinon deconfinement (or spin-charge
separation) are distinguished from those with spinon confinement by distinct
impurity susceptibilities and finite-size spectra. We discuss the evolution of
physical properties upon doping to a d-wave superconductor, and argue that a
number of recent experiments favor spinon confinement in the reference Mott
insulating state.

</DOC>
<DOC>
<DOCNO> 80779 </DOCNO>
A variant approach to the overlap action


  I describe an implementation of the overlap action, which is built from an
action which is itself an approximate overlap action. It appears to be about a
factor of 15-20 less expensive to use, than the usual overlap action with the
Wilson fermion action as its kernel. Ingredients include a fat link to suppress
coupling to dislocations and a free field action with a spectrum which
resembles an overlap; much of the gain comes from the use of eigenmodes of the
approximate action to begin the overlap calculation. As a physics example, I
compute the quark condensate in finite volume in the quenched approximation.

</DOC>
<DOC>
<DOCNO> 39719 </DOCNO>
From Accelerators To Asteroids


  In this talk I discuss the reach of traditional methods of elementary
particle physics in five broad experimental areas. For each of these areas I
inquire how that reach is, or might be, extended by experimental and
observational astrophysics and astronomy. The five areas are: searches for
particles with very large masses and measuring those masses, searches for
particles with very small masses and measuring those masses, searches for new
types of particles, searches for unexpected behavior of the known forces or for
new forces and searches for new phenomena at very high energies.

</DOC>
<DOC>
<DOCNO> 13271 </DOCNO>
Topological Description of the Aging Dynamics in Simple Glasses


  We numerically investigate the aging dynamics of a monatomic Lennard-Jones
glass, focusing on the topology of the potential energy landscape which, to
this aim, has been partitioned in basins of attraction of stationary points
(saddles and minima). The analysis of the stationary points visited during the
aging dynamics shows the existence of two distinct regimes: i) at short times,
t<t_c, the system visits basins of saddles whose energies and orders decrease
with t; ii) at long times, t>t_c, the system mainly lies in basins pertaining
to minima of slowly decreasing energy. The dynamics for t>t_c can be
represented by a simple random walk on a network of minima with a jump
probability proportional to the inverse of the waiting time.

</DOC>
<DOC>
<DOCNO> 10714 </DOCNO>
Application of the quantum spin glass theory to image restoration


  Quantum fluctuation is introduced into the Markov random fields (MRF's) model
for image restoration in the context of Bayesian approach. We investigate the
dependence of the quantum fluctuation on the quality of BW image restoration by
making use of statistical mechanics. We find that the maximum posterior
marginal (MPM) estimate based on the quantum fluctuation gives a fine
restoration in comparison with the maximum a posterior (MAP) estimate or the
thermal fluctuation based MPM estimate.

</DOC>
<DOC>
<DOCNO> 101236 </DOCNO>
Multiresolution Representations for Solutions of Vlasov-Maxwell-Poisson


  We present the applications of variational-wavelet approach for computing
multiresolution/multiscale representation for solution of some approximations
of Vlasov-Maxwell-Poisson equations.

</DOC>
<DOC>
<DOCNO> 116927 </DOCNO>
Beam Switching and Beam Feedback Systems at KEKB Linac


  The KEK 8-GeV electron / 3.5-GeV positron linac has been operated with very
different beam specifications for downstream rings, KEKB, PF and PF-AR. For the
reliable operation among these beam modes intelligent beam switching and beam
feedback systems have been developed and used since its commissioning.
 A software panel is used to choose one of four beam modes and a switching
sequence is executed in about two minutes. Most items in a sequence are simple
operations followed by failure recoveries. The magnet standardization part
consumes most of the time. The sequence can be re-arranged easily by
accelerator operators. Linac beam modes are switched about fifty times a day
using this software.
 In order to stabilize linac beam energy and orbits, as well as some
accelerator equipment, about thirty software beam feedback loops have been
installed. They have been utilized routinely in all beam modes, and have
improved its beam quality. Since its software interfaces are standardized, it
is easy to add new feedback loops simply defining monitors and actuators.

</DOC>
<DOC>
<DOCNO> 119012 </DOCNO>
Constraints on the Cosmic Infra-Red Background based on BeppoSAX and CAT


  The TeV and X-ray data obtained by the imaging Cherenkov telescope CAT and
X-ray satellite BeppoSAX during the remarkable flare of Mkn 501 in April 16,
1997 are used to constrain the flux of the Cosmic Infrared Background (CIB)
using different CIB models. We show that a non-negligible absorption of
gamma-rays due to the CIB could take place already in the low-energy (sub-TeV)
domain of the spectrum of Mkn 501. This implies that the data of the low-energy
threshold CAT telescope contain very important information about the CIB at
short wavelengths, 0.4 mum <= lambda <= 3. mum. The analysis of almost
simultaneous spectroscopic measurements of Mkn 501 in a high state by CAT and
BeppoSAX in the framework of the standard homogeneous Synchrotron-Self-Compton
(SSC) framework model leads to the conclusion that the density of the
near-infrared background with typical ``starlight spectrum'' around 1 mum
should be between 5 and 35 nW m^-2 sr^-1 (99 % CL), with most likely value
around 20 nW m^-2 sr^-1. Also we argue that the CAT gamma-ray data alone allow
rather robust upper limits on the CIB, lambda F_lambda <= 60 nW m^-2 sr^-1 at 1
mum, taking into account that for any reasonable scenario of gamma-ray
production the differential intrinsic spectrum of gamma-ray hardly could be
flatter than dN/dE == E^-1. This estimate agrees, within statistical and
systematic uncertainties, with recent reports about tentative detections of the
CIB at 2.2 and 3.5 mum by the Diffuse Infrared Background Experiment (DIRBE),
as well as with the measurements of the background radiation at optical
wavelengths from absolute photometry. We also discuss the impact of the
intergalactic absorption effect in derivation of the SSC parameters for the jet
in Mkn 501.

</DOC>
<DOC>
<DOCNO> 117216 </DOCNO>
A Historical Perspective on Cancer


  It is proposed that cancer results from the breakdown of universal control
mechanisms which developed in mutual association as part of the historical
process that brought individual cells together into multi-cellular communities.
By systematically comparing the genomes of uni-celled with multi-celled
organisms, one might be able to identify the most promising sites for
intervention aimed at restoring the damaged control mechanisms and thereby
arresting the cancer.

</DOC>
<DOC>
<DOCNO> 69519 </DOCNO>
Wavelets on nuclear interactions and QCD on jet multiplicities


  This talk at Fradkin conference is devoted to brief description of latest
results in two topics I worked on during last years. The multiresolution
analysis and fast wavelet transform became a standard procedure for pattern
recognition and I describe how it has been used for analysis of high energy
nucleus-nucleus interactions. Latest QCD results on multiplicities in quark and
gluon jets are discussed and confronted to experimental data.

</DOC>
<DOC>
<DOCNO> 100418 </DOCNO>
Jonssons's theorem in non-modular varieties


  A version of Jonsson's theorem, as previously generalized, holds in
non-modular varieties.

</DOC>
<DOC>
<DOCNO> 102319 </DOCNO>
Some families of special Lagrangian tori


  We give a simple proof of the local version of a result of R. Bryant, stating
that any 3-dimensional Riemannian manifold can be isometrically embedded as a
special Lagrangian submanifold in a Calabi-Yau manifold. We refine the theorem
proving that a certain class of one-parameter families of metrics on a 3-torus
can be isometrically embedded in a Calabi-Yau manifold as a one-parameter
family of special Lagrangian submanifolds. We use our examples of one-parameter
families to show that the semi-flat metric on the mirror manifold proposed be
N. Hitchin is not necessarily Ricci-flat in dimension 3.

</DOC>
<DOC>
<DOCNO> 117151 </DOCNO>
Optimal Recovery of Local Truth


  Probability mass curves the data space with horizons. Let f be a multivariate
probability density function with continuous second order partial derivatives.
Consider the problem of estimating the true value of f(z) > 0 at a single point
z, from n independent observations. It is shown that, the fastest possible
estimators (like the k-nearest neighbor and kernel) have minimum asymptotic
mean square errors when the space of observations is thought as conformally
curved. The optimal metric is shown to be generated by the Hessian of f in the
regions where the Hessian is definite. Thus, the peaks and valleys of f are
surrounded by singular horizons when the Hessian changes signature from
Riemannian to pseudo-Riemannian. Adaptive estimators based on the optimal
variable metric show considerable theoretical and practical improvements over
traditional methods. The formulas simplify dramatically when the dimension of
the data space is 4. The similarities with General Relativity are striking but
possibly illusory at this point. However, these results suggest that
nonparametric density estimation may have something new to say about current
physical theory.

</DOC>
<DOC>
<DOCNO> 71717 </DOCNO>
Confinement in the Big Bang and Deconfinement in the Little Bangs at


  The evolution of strongly interacting matter during the cosmological
confinement transition is reviewed. Despite of many proposed relics no specific
signal from the rearrangement of quarks and gluons into hadrons has been
identified by observations. In contrast to this, several observables in
heavy-ion collisions at CERN-SPS energies point to the creation of a matter
state near or slightly above deconfinement. We focus here on the analysis of
dileptons and direct photons. Similarities and differences of the Big Bang and
the Little Bang confinement dynamics are elaborated.

</DOC>
<DOC>
<DOCNO> 119385 </DOCNO>
Harmonically dancing space-time nodes: quantitatively deriving


  The microscopic structure of space and time is investigated. It is proposed
that space and time of an inertial observer $\Sigma$ are most conveniently
described as a crystal array $\Lambda$, with nodes representing measurement
`tickmarks' and connected by independent quantized harmonic oscillators which
vibrate more severely the faster $\Sigma$ moves with respect to the object
being measured (due to the Uncertainty Principle). The Lorentz transformation
of Special Relativity is derived. Further, mass is understood as a localized
region $\Delta \Lambda$ having higher vibration temperature than that of the
ambient lattice. The effect of relativistic mass increase may then be
calculated without appealing to energy-momentum conservation. The origin of
gravitation is shown to be simply a transport of energy from the boundary of
$\Delta \Lambda$ outwards by lattice phonon conduction, as the system tends
towards equilibrium. Application to a single point mass leads readily to the
Schwarzschild metric, while a new solution is available for two point masses -
a situation where General Relativity is too complicated to work with. The
important consequence is that inertial observers who move at relative speeds
too close to $c$ are no longer linked by the Lorentz transformation, because
the lattice of the `moving' observer has already disintegrated into a liquid
state.

</DOC>
<DOC>
<DOCNO> 169831 </DOCNO>
Phase shift operator and cyclic evolution in finite dimensional Hilbert


  We address the problem of phase shift operator acting as time evolution
operator in Pegg-Barnett formalism. It is argued that standard shift operator
is inconsistent with the behaviour of the state vector under cyclic evolution.
We consider a generally deformed oscillator algebra at q-root of unity, as it
yields the same Pegg-Barnett operator and show that shift operator meets our
requirement.

</DOC>
<DOC>
<DOCNO> 117299 </DOCNO>
Dipole Mode Detuning in the Injector Linacs of the NLC


  The injector linacs of the JLC/NLC project include the prelinac, the e+ drive
linac, the $e- booster, and the $e+ booster. The first three will be S-band
machines, the last one, an L-band machine. We have demonstrated that by using
detuning alone in the accelerator structure design of these linacs we will have
acceptable tolerances for emittance growth due to both injection jitter and
structure misalignments, for both the nominal (2.8ns) and alternate (1.4ns)
bunch spacings.

</DOC>
<DOC>
<DOCNO> 122979 </DOCNO>
DENIS-P J104814.7-395606.1: An M9 dwarfs at about 4 pc


  We present the discovery of a previously unknown member of the immediate
solar neighbourhood, DENIS-P J104814.7-395606.1 (hereafter DENIS 1048-39),
identified while mining the DENIS database for new nearby stars. A HIRES
echelle spectrum obtained with the 10-m Keck telescope shows that it is an M9
dwarf. DENIS 1048-39 has a very bright apparent magnitude (I=12.67) for its
spectral type and colour (I-J=3.07), and is therefore very nearby. If it is
single its distance is only 4.1 +- 0.6pc, ranking it as between our twelfth and
fortyth closest neighbour. It is also the closest star or brown dwarf with a
spectral type later than M7V. Its proper motion was determined through
comparison of Sky atlas Schmidt plates, scanned by the MAMA microdensitometer,
with the DENIS images. At 1.53"/yr it further attests the closeness of DENIS
1048-39, and hence its dwarf status. These characteristics make it an obvious
target for further detailed studies.

</DOC>
<DOC>
<DOCNO> 67898 </DOCNO>
Top-Antitop Pair Production close to Threshold: Synopsis of recent NNLO


  Using non-relativistic effective theories, new next-to-next-to-leading order
(NNLO) QCD corrections to the total $t\bar t$ production cross section at the
Linear Collider have been calculated recently. In this article the NNLO
calculations of several groups are compared and the remaining uncertainties are
discussed. The theoretical prospects for an accurate determination of top quark
mass parameters are discussed in detail. An outlook on possible future
improvements is given.

</DOC>
<DOC>
<DOCNO> 9964 </DOCNO>
Waveguides coupled through a semitransparent barrier: a Birman-Schwinger


  The paper is devoted to a model of a mesoscopic system consisting of a pair
of parallel planar waveguides separated by an infinitely thin semitransparent
boundary modeled by a transverse delta interaction. We develop the
Birman-Schwinger theory for the corresponding generalized Schroedinger
operator. The spectral properties become nontrivial if the barrier coupling is
not invariant with respect to longitudinal translations, in particular, there
are bound states if the barrier is locally more transparent in the mean and the
coupling parameter reaches the same asymptotic value in both directions along
the guide axis. We derive the weak-coupling expansion of the ground-state
eigenvalue for the cases when the perturbation is small in the supremum and the
L^1-norms. The last named result applies to the situation when the support of
the leaky part shrinks: the obtained asymptotics differs from that of a double
guide divided by a pierced Dirichlet barrier. We also derive an upper bound on
the number of bound states.

</DOC>
<DOC>
<DOCNO> 71295 </DOCNO>
Near-to-planar 3-jet events in and beyond QCD perturbation theory


  We present the results of QCD analysis of out-of-event-plane momentum
distribution in 3-jet e+e- annihilation events. We consider the all-order
resummed perturbative prediction and the leading power suppressed
non-perturbative corrections to the mean value <K_out> and the distribution and
explain their non-trivial colour structure. The technique we develop aims at
improving the accuracy of the theoretical description of multi-jet ensembles,
in particular in hadron-hadron collisions.

</DOC>
<DOC>
<DOCNO> 117530 </DOCNO>
The 1996 outburst of GRO J1655-40: disc irradiation and enhanced mass


  We show that the 1996 outburst of the X-ray binary transient system GRO
J1655-40 can be explained by the standard dwarf-nova type disc instability,
followed by an episode of enhanced mass transfer from the secondary if the mass
transfer rate in GRO J1655-40 is within a factor < 10 of the stability limit.
We argue that irradiation of the secondary during the onset of the outburst
driven by the thermal instability in the outer disc can increase the mass
transfer rate above the minimum value required for stable accretion. This will
then produce the period of near-constant X-ray emission seen in this system.
This scenario can also explain the observed anti-correlation between the
optical and X-ray fluxes. It is generally accepted that optical emission in
low-mass X-ray binaries is produced by irradiation of the outer disc by X-rays.
There is also strong circumstantial evidence that in order for the outer disc
to see the irradiating flux, it must be warped. Depending on the warp
propagation mechanism, either a burst of mass from the secondary or viscous
decay are likely to decrease the degree of warping, thereby causing the
decrease in the observed optical flux while the X-ray flux remains constant or
even increases, exactly as observed in GRO J1655-40. Finally, the decrease of
the disc warping and, therefore, irradiation will cause the disc to become
unstable once again, terminating the outburst.

</DOC>
<DOC>
<DOCNO> 13287 </DOCNO>
Maximum Entropy Analysis of the Spectral Functions in Lattice QCD


  First principle calculation of the QCD spectral functions (SPFs) based on the
lattice QCD simulations is reviewed. Special emphasis is placed on the Bayesian
inference theory and the Maximum Entropy Method (MEM), which is a useful tool
to extract SPFs from the imaginary-time correlation functions numerically
obtained by the Monte Carlo method. Three important aspects of MEM are (i) it
does not require a priori assumptions or parametrizations of SPFs, (ii) for
given data, a unique solution is obtained if it exists, and (iii) the
statistical significance of the solution can be quantitatively analyzed.
  The ability of MEM is explicitly demonstrated by using mock data as well as
lattice QCD data. When applied to lattice data, MEM correctly reproduces the
low-energy resonances and shows the existence of high-energy continuum in
hadronic correlation functions. This opens up various possibilities for
studying hadronic properties in QCD beyond the conventional way of analyzing
the lattice data. Future problems to be studied by MEM in lattice QCD are also
summarized.

</DOC>
<DOC>
<DOCNO> 10212 </DOCNO>
How to experimentally measure the number 5 of the SO(5) theory?


  According to Wilson's theory of critical phenomena, critical exponents are
universal functions of $d$, the dimension of space, and $n$, the dimension of
the symmetry group. SO(5) theory of antiferromagnetism and superconductivity
predicts a bicritical point where $T_N$ and $T_c$ intersect. By measuring
critical exponents close to the bicritical point, and knowing that $d=3$, one
can experimentally measure the number 5 of the SO(5) theory.

</DOC>
<DOC>
<DOCNO> 169586 </DOCNO>
Canonical Quantum Teleportation


  Canonically conjugated observables such as position-momentum and phase-number
are found to play a 3-fold role in the drama of the quantum teleportation.
Firstly, the common eigenstate of two commuting canonical observables like
phase-difference and number-sum provides the quantum channel between two
systems. Secondly, a similar pair of canonical observables from another two
systems is measured in the Bell operator measurements.

</DOC>
<DOC>
<DOCNO> 12719 </DOCNO>
Switch of lamellae orientation in slits


  Effect of hydrophilicity of the confining walls on lamellar phases in
oil-water-surfactant mixtures is studied in a slit geometry. In contrast to
strongly hydrophilic or hydrophobic walls, which induce parallel orientation of
lamellae, the lamellae can be oriented perpendicularly to the neutral walls
when the material properties and the termodynamical state of the sample are
suitably chosen. When the elastic energy associated with compression or
decompression of the lamellae parallel to very weakly hydrophilic walls is
sufficiently large, then changes of the film thickness lead to a switch from
the parallel to the perpendicular orientation of the lamellae. Our general
arguments are confirmed by explicit mean-field calculations in a lattice vector
model.

</DOC>
<DOC>
<DOCNO> 40388 </DOCNO>
A Limit on the Polarized Anisotropy of the Cosmic Microwave Background


  A ground-based polarimeter, PIQUE, operating at 90 GHz has set a new limit on
the magnitude of any polarized anisotropy in the cosmic microwave background.
The combination of the scan strategy and full width half maximum beam of 0.235
degrees gives broad window functions with average multipoles, l = 211+294-146
and l = 212+229-135 for the E- and B-mode window functions, respectively. A
joint likelihood analysis yields simultaneous 95% confidence level flat band
power limits of 14 and 13 microkelvin on the amplitudes of the E- and B-mode
angular power spectra, respectively. Assuming no B-modes, a 95% confidence
limit of 10 microkelvin is placed on the amplitude of the E-mode angular power
spectrum alone.

</DOC>
<DOC>
<DOCNO> 169697 </DOCNO>
Continuous pumping and control of mesoscopic superposition state in a


  Here we consider the continuous pumping of a dissipative QED cavity and
derive the time-dependent density operator of the cavity field prepared
initially as a superposition of mesoscopic coherent states. The control of the
coherence of this superposition is analyzed considering the injection of a beam
of two-level Rydberg atoms through the cavity. Our treatment is compared to
other approaches.

</DOC>
<DOC>
<DOCNO> 102129 </DOCNO>
Symplectomorphism groups and almost complex structures


  This paper studies groups of symplectomorphisms of ruled surfaces for
symplectic forms with varying cohomology class. This class is characterized by
the ratio R of the size of the base to that of the fiber. By considering
appropriate spaces of almost complex structures, we investigate how the
topological type of these groups changes as R increases. If the base is a
sphere, this changes precisely when R passes an integer, and for general bases
it stabilizes as R goes to infinity. Our results extend and make more precise
some of the conclusions of Abreu--McDuff concerning the rational homotopy type
of these groups for rational ruled surfaces.

</DOC>
<DOC>
<DOCNO> 83420 </DOCNO>
Using existing systems to supplement small amounts of annotated


  Grammatical relationships (GRs) form an important level of natural language
processing, but different sets of GRs are useful for different purposes.
Therefore, one may often only have time to obtain a small training corpus with
the desired GR annotations. To boost the performance from using such a small
training corpus on a transformation rule learner, we use existing systems that
find related types of annotations.

</DOC>
<DOC>
<DOCNO> 102552 </DOCNO>
A Path Algorithm for Affine Kazhdan-Lusztig Polynomials


  We develop an algorithm for computing affine Kazhdan-Lusztig polynomials, for
all Lie types. This generalizes our previously published algorithm for type A,
which in turn is a faster version of an algorithm due to Lascouz, Leclerc and
Thibon (proposed in the setting of Hecke algebras of type A, at roots of
unity.)

</DOC>
<DOC>
<DOCNO> 123241 </DOCNO>
X-ray variability of AGN and correlations with spectral properties


  Rapid flux changes in the X-ray emission from active galactic nuclei are
commonly observed. The power-density spectra show a pseudo power-law form with
a turnover at low frequencies and a high frequency break, similar to galactic
black-hole candidates. There have been a few claims for periodicities but these
are not a well-established property of the class. The amplitude of variability
depends on a number of source parameters, including luminosity and spectral
properties. The variability amplitude is correlated with X-ray spectral index,
and anti-correlated with the width of the permitted optical lines. In one
particularly well-observed case, NGC 7469, we see a relationship between the
X-ray and UV variability, which indicates that the dominant emission process
for the X-rays is thermal Comptonization. Variations in the X-ray emission are
related to changes in the UV seed photons, but it appears there must also be a
mechanism - perhaps that which heats the Comptonizing corona - that induces
rapid variability intrinsic to the X-rays.

</DOC>
<DOC>
<DOCNO> 151167 </DOCNO>
Superconformal interpretation of BPS states in AdS geometries


  We carry out a general analysis of the representations of the superconformal
algebras SU(2,2/N), OSp(8/4,R) and OSp(8^*/4) and give their realization in
superspace. We present a construction of their UIR's by multiplication of the
different types of massless superfields ("supersingletons"). Particular
attention is paid to the so-called "short multiplets". Representations
undergoing shortening have "protected dimension" and correspond to BPS states
in the dual supergravity theory in anti-de Sitter space. These results are
relevant for the classification of multitrace operators in boundary conformally
invariant theories as well as for the classification of AdS black holes
preserving different fractions of supersymmetry.

</DOC>
<DOC>
<DOCNO> 12485 </DOCNO>
Magnetization jump in the XXZ chain with next-nearest-neighbor exchange


  We study the dependence of the magnetization M with magnetic field B at zero
temperature in the spin-1/2 XXZ chain with nearest-neighbor (NN) J1 and next-NN
J2 exchange interactions, with anisotropies Delta1 and Delta2 respectively. The
region of parameters for which a jump in M(B) exists is studied using numerical
diagonalization, and analytical results for two magnons on a ferromagnetic
background in the thermodynamic limit. We find a line in the parameter space
(J2/J1, Delta1/J1, Delta2/J2) (determined by two simple equations) at which the
ground state is highly degenerate. M(B) has a jump near this line, and at or
near the isotropic case with ferromagnetic J1 and antiferromagnetic J2, with
|J2/J1| near 1/4. These results are relevant for some systems containing CuO
chains with edge-sharing CuO4 units.

</DOC>
<DOC>
<DOCNO> 123118 </DOCNO>
Optical and X-ray monitoring of the NLS1 galaxy Ark 564


  The Narrow-line Seyfert galaxy Ark 564 was monitored between June 04, 2000
and June 24, 2000 from Skinakas Observatory. The B,V,R and I band light curves
show night to night variations of 0.1 mag. Comparison with X-ray data from a
simultaneous ASCA observation shows that the X-ray variations are more
pronounced than in the optical band. Cross correlation analysis yields a time
lag of ~ 0.8 days in the sense that the X-rays are leading the optical but with
low statistical significance. We discuss possible implications of our results
to current physical models of AGN.

</DOC>
<DOC>
<DOCNO> 178636 </DOCNO>
Dynamics of low-energy nuclear forces for electromagnetic and weak


  A dynamics of low-energy nuclear forces is investigated for low-energy
electromagnetic and weak nuclear reactions with the deuteron in the
Nambu-Jona-Lasinio model of light nuclei by example of the neutron-proton
radiative capture (M1-capture) n + p -> D + photon, the photomagnetic
disintegration of the deuteron photon + D -> n + p and weak reactions of
astrophysical interest. These are the solar proton burning p + p -> D +
positron + nu_e, the pep-process p + electron + p -> D + nu_e and the neutrino
and anti-neutrino disintegration of the deuteron caused by charged nu_e + D ->
electron + p + p, anti-nu_e + D -> positron + n + n and neutral nu_e(anti-nu_e)
+ D -> nu_e(ant-nu_e) + n + p weak currents.

</DOC>
<DOC>
<DOCNO> 118109 </DOCNO>
The power spectral properties of the Z-source GX 340+0


  We present an analysis of ~390 ksec of data of the Z source GX 340+0 taken
during 24 observations with the Rossi X-ray Timing Explorer satellite. We
report the discovery of a new broad component in the power spectra. The
frequency of this component varied between 9 and 14 Hz, and remained close to
half that of the horizontal branch quasi-periodic oscillations (HBO). Its rms
amplitude was consistent with being constant around ~5%, while its FWHM
increased with frequency from 7 to 18 Hz. If this sub-HBO component is the
fundamental frequency, then the HBO and its second harmonic are the second and
fourth harmonic component, while the third harmonic was not detected. This is
similar to what was recently found for the black hole candidate XTE J1550-564.
The profiles of both the horizontal- and the normal branch quasi-periodic
oscillation peaks were asymmetric when they were strongest. We describe this in
terms of a shoulder component at the high frequency side of the quasi-periodic
oscillation peak, whose rms amplitudes were approximately constant at ~4% and
\~3%, respectively. The peak separation between the twin kHz quasi-periodic
oscillations was consistent with being constant at 339+-8 Hz but a trend
similar to that seen in, e.g. Sco X-1 could not be excluded. We discuss our
results within the framework of the various models which have been proposed for
the kHz QPOs and low frequency peaks.

</DOC>
<DOC>
<DOCNO> 69845 </DOCNO>
The Compatibility of the Gluon Reggeization with the s-channel Unitarity


  Recently the non-forward BFKL kernel for interaction of two Reggeized gluons
in the antisymmetric colour octet state in the $t$-channel was obtained in the
next-to-leading order. It gives the possibility to check in this order the
bootstrap condition for this kernel, appearing as the requirement of the
compatibility of gluon Reggeization with the $s$-channel unitarity.

</DOC>
<DOC>
<DOCNO> 7813 </DOCNO>
Trans-Planckian redshifts and the substance of the space-time river


  Trans-Planckian redshifts in cosmology and outside black holes may provide
windows on a hypothetical short distance cutoff on the fundamental degrees of
freedom. In cosmology, such a cutoff seems to require a growing Hilbert space,
but for black holes, Unruh's sonic analogy has given rise to both field
theoretic and lattice models demonstrating how such a cutoff in a fixed Hilbert
space might be compatible with a low energy effective quantum field theory of
the Hawking effect. In the lattice case, the outgoing modes arise via a Bloch
oscillation from ingoing modes. A short distance cutoff on degrees of freedom
is incompatible with local Lorentz invariance, but may nevertheless be
compatible with general covariance if the preferred frame is defined
non-locally by the cosmological background. Pursuing these ideas in a different
direction, condensed matter analogs may eventually allow for laboratory
observations of the Hawking effect. This paper introduces and gives a fairly
complete but brief review of the work that has been done in these areas, and
tries to point the way to some future directions.

</DOC>
<DOC>
<DOCNO> 99829 </DOCNO>
Fourier transform over finite field and identities between Gauss sums


  This is a sequel to math.AG/0003009. Here we study identities for the Fourier
transform of "elementary functions" over finite field containing "exponents" of
monomial rational functions. It turns out that these identities are governed by
monomial identities between Gauss sums. We show that similar to the case of
complex numbers such identities correspond to linear relations between certain
divisors on the space of multiplicative characters.

</DOC>
<DOC>
<DOCNO> 174554 </DOCNO>
Gamma-ray strength function and pygmy resonance in rare earth nuclei


  The gamma-ray strength function for gamma energies in the 1-7 MeV region has
been measured for 161,162-Dy and 171,172-Yb using the (3-He,alpha gamma)
reaction. Various models are tested against the observed gamma-ray strength
functions. The best description is based on the Kadmenskii, Markushev and
Furman E1 model with constant temperature and the Lorentzian M1 model. A
gamma-ray bump observed at E_gamma=3 MeV is interpreted as the so-called pygmy
resonance, which has also been observed previously in (n,gamma) experiments.
The parameters for this resonance have been determined and compared to the
available systematics.

</DOC>
<DOC>
<DOCNO> 119895 </DOCNO>
High-Redshift, Radio-Loud Quasars


  I discuss two programs to study radio-loud quasars at high (z>4) redshift.
Quasars are the most luminous, non-transient objects known and are observed to
the earliest cosmic epochs. At lower redshifts, radio-loud quasars are
associated with host galaxies having deVaucoleurs profiles. By association,
identifying and studying a sample of high-redshift, radio-loud quasars provides
important clues to the early Universe and potentially probes early-type galaxy
formation. The first aspect of this proceeding discusses an extensive search
for high-redshift, radio-loud quasars culled from matching the FIRST radio
catalog with the 2nd generation Palomar Sky Survey. The second aspect of this
proceeding concerns studying the radio properties of optically-selected z>4
quasars. At the time of this conference, only seven z>4 quasars were in the
literature. The first program discussed herein uncovers three new such sources,
while the second program identifies an additional five. We use the new samples
to study the evolution of the radio-loud fraction, finding no evolution in this
quantity between redshift z>2 and z>4 for -26>M(B)>-28.

</DOC>
<DOC>
<DOCNO> 101215 </DOCNO>
Classification of indefinite hyper-Kaehler symmetric spaces


  We classify indefinite simply connected hyper-Kaehler symmetric spaces. Any
such space without flat factor has commutative holonomy group and signature
(4m,4m). We establish a natural 1-1 correspondence between simply connected
hyper-Kaehler symmetric spaces of dimension 8m and orbits of the general linear
group GL(m,H) over the quaternions on the space (S^4C^n)^{\tau} of homogeneous
quartic polynomials S in n = 2m complex variables satisfying the reality
condition S = \tau S, where \tau is the real structure induced by the
quaternionic structure of C^{2m} = H^m. We define and classify also complex
hyper-Kaehler symmetric spaces. Such spaces without flat factor exist in any
(complex) dimension divisible by 4.

</DOC>
<DOC>
<DOCNO> 99623 </DOCNO>
Virtual Gromov-Witten Invariants and the Quantum Cohomology Rings of


  In this paper, we propose another characterization of the generalized mirror
transformation on the quantum cohomology rings of general type projective
hypersurfaces. This characterics is useful for explicit determination of the
form of the generalized mirror transformation. As applications, we rederive the
generalized mirror transformation up to $d=3$ rational Gromov-Witten invariants
obtained in our previous article, and determine explicitly the the generalized
mirror transformation for the $d=4, 5$ rational Gromov-Witten invariants in the
case when the first Chern class of the hypersurface equals $-H$ (i.e.,
$k-N=1$).

</DOC>
<DOC>
<DOCNO> 120434 </DOCNO>
The Initial Mass Function of Low-Mass Stars and Brown Dwarfs in Taurus


  By combining deep optical imaging and infrared spectroscopy with data from
the Two-Micron All-Sky Survey (2MASS) and from previous studies (e.g., Briceno
et al.), I have measured the Initial Mass Function (IMF) for a
reddening-limited sample in four fields in the Taurus star forming region. This
IMF is representative of the young populations within these fields for masses
above 0.02 Msun. Relative to the similarly derived IMF for the Trapezium
Cluster (Luhman et al.), the IMF for Taurus exhibits a modest deficit of stars
above one solar mass (i.e., steeper slope), the same turnover mass (~0.8 Msun),
and a significant deficit of brown dwarfs. If the IMF in Taurus were the same
as that in the Trapezium, 12.8+/-1.8 brown dwarfs (>0.02 Msun) are expected in
these Taurus fields where only one brown dwarf candidate is found. These
results are used to test theories of the IMF.

</DOC>
<DOC>
<DOCNO> 174615 </DOCNO>
Status of experimental investigations of $\eta$-mesic nuclei


  Short history of ideas concerning a possible existence of bound states of the
$\eta$-meson and a nucleus is considered. First experiments at BNL and LAMPF on
searching for these states are discussed. Another recent experiment using the
photon beam of the 1 GeV electron synchrotron of LPI is described. Possible
experiments on studying $\eta$-mesic nuclei using a proton beam (at Nuclotron
of Dubna) and a $\gamma$-beam (CEBAF, JLAB) are suggested.

</DOC>
<DOC>
<DOCNO> 40440 </DOCNO>
QCD at the Tevatron: Jets and Fragmentation


  At the Fermilab Tevatron energies, ($\sqrt{s}$=1800 GeV and $\sqrt{s}$=630
GeV), jet production is the dominant process. During the period 1992-1996, the
D0 and CDF experiments accumulated almost 100 pb**-1 of data and performed the
most accurate jet production measurements up to this date. These measurements
and the NLO-QCD theoretical predictions calculated during the last decade, have
improved our understanding of QCD, our knowledge of the proton structure, and
pushed the limit to the scale associated with quark compositeness to 2.4-2.7
TeV. In this paper, we present the most recent published and preliminary
measurements on jet production and fragmentation by the D0 and CDF
collaborations.

</DOC>
<DOC>
<DOCNO> 99402 </DOCNO>
A new method in Fano geometry


  We give some bounds on the anticanonical degrees of Fano varieties with
Picard number 1 and mild singularities, extending results of Koll\'ar et al.
from the early 90's and improving them even in the smooth case. The proof is
based on a study of positivity properties of sheaves of differential operators
on ample line bundles, and avoids the use of rational curves and
bend-and-break. This note is a self-contained exposition of the main ideas of
math.AG/9811022

</DOC>
<DOC>
<DOCNO> 71353 </DOCNO>
Note on the Thermal Behavior of the Neutron Electric Dipole Moment from


  We use the method of thermal QCD sum rules to investigate the effects of
temperature on the neutron electric dipole moment d_n induced by the vacuum
\bar{\theta}-angle. Then, we analyze and discuss the thermal behaviour of the
ratio {d_n \over \bar{\theta}} in connection with the restoration of the strong
CP symmetry breaking.

</DOC>
<DOC>
<DOCNO> 99934 </DOCNO>
Generalised Hilbert Numerators II


  We associate to each $r$-multigraded, locally finitely generated ideal in the
"large polynomial ring" on countably many indeterminates a power series in $r$
variables; this power series is the limit in the adic topology of the
numerators of the rational functions which give the Hilbert series of the
truncations of the ideal. We characterise the set of all power series so
obtained.
  Our main technical tools are an approximation result which asserts that
truncation and the forming of initial ideals commute in a filtered sense, and
standard inclusion/exclusion, M\"obius inversion, and LCM-lattice homology
methods generalised to monomial ideals in countably many variables.

</DOC>
<DOC>
<DOCNO> 84359 </DOCNO>
On the ADM Equations for General Relativity


  The Arnowitt-Deser-Misner (ADM) evolution equations for the induced metric
and the extrinsic-curvature tensor of the spacelike surfaces which foliate the
space-time manifold in canonical general relativity are a first-order system of
quasi-linear partial differential equations, supplemented by the constraint
equations. Such equations are here mapped into another first-order system. In
particular, an evolution equation for the trace of the extrinsic-curvature
tensor K is obtained whose solution is related to a discrete spectral
resolution of a three-dimensional elliptic operator P of Laplace type.
Interestingly, all nonlinearities of the original equations give rise to the
potential term in P. An example of this construction is given in the case of a
closed Friedmann-Lemaitre-Robertson-Walker universe. Eventually, the ADM
equations are re-expressed as a coupled first-order system for the induced
metric and the trace-free part of K. Such a system is written in a form which
clarifies how a set of first-order differential operators and their inverses,
jointly with spectral resolutions of operators of Laplace type, contribute to
solving, at least in principle, the original ADM system.

</DOC>
<DOC>
<DOCNO> 101516 </DOCNO>
Exactness and stability in homotopical algebra


  Exact sequences are a well known notion in homological algebra. We
investigate here the more vague properties of 'homotopical exactness',
appearing for instance in the fibre or cofibre sequence of a map.
 Such notions of exactness can be given for very general 'categories with
homotopies' having homotopy kernels and cokernels, but become more interesting
under suitable stability hypotheses, satisfied - in particular - by chain
complexes. It is then possible to measure the default of homotopical exactness
of a sequence by the homotopy type of a certain object, a sort of 'homotopical
homology'.

</DOC>
<DOC>
<DOCNO> 178433 </DOCNO>
Strongly damped nuclear collisions: zero or first sound ?


  The relaxation of the collective quadrupole motion in the initial stage of a
central heavy ion collision at beam energies $E_{lab}=5\div20$ AMeV is studied
within a microscopic kinetic transport model. The damping rate is shown to be a
non-monotonic function of E_{lab} for a given pair of colliding nuclei. This
fact is interpreted as a manifestation of the zero-to-first sound transition in
a finite nuclear system.

</DOC>
<DOC>
<DOCNO> 117188 </DOCNO>
Dynamics of Chemical Reactions: Open Equilibrium


  Dynamic properties of chemical reactions and appropriate relationships for
open chemical equilibrium are discussed in approach of the chemical dynamics.
New way to calculate composition of chemical systems in open equilibrium, based
on the amended equation for the change of Gibbs' free energy, was exemplified
using reactions of cobalt double oxides with sulfur. Evaluated this way
equilibrium reaction extents had a good match with values found by direct
thermodynamic simulation. The developed method allows us to perform analysis of
complex chemical systems without coefficients of thermodynamic activity. In
cases when the coefficients are in need or just desirable, the method offers a
simple way to calculate them. Possible systems to apply method of chemical
dynamics are discussed.

</DOC>
<DOC>
<DOCNO> 151230 </DOCNO>
On B-independence of RR charges


  Generalization of the recent Taylor-Polchinski argument is presented, which
helps to explain quantization of RR charges in IIA-like theories in the
presence of cohomologically trivial H-fields.

</DOC>
<DOC>
<DOCNO> 102283 </DOCNO>
Uniformly Generating Distribution Functions for Discrete Random


  An algorithm is presented which, with optimal efficiency, solves the problem
of uniform random generation of distribution functions for an n-valued random
variable.

</DOC>
<DOC>
<DOCNO> 13470 </DOCNO>
Accurate Computation of the Magnetic Susceptibility for the Normal Phase


  The magnetic susceptibility of the quarter-filled one-dimensional extended
Hubbard model is calculated using the density-matrix renormalization group
technique.
  It is found that in the charge gap regime of the model ($U> 4t $ and $V >
2t$), or in the metallic region with important superconductive fluctuations
($U<4t$ and $V>2t$), $\chi(T)$ displays a singularity at T=0 and an inflection
point at low temperatures that are similar to what occurs in the spin-half
quantum spin chain. These results, whose accuracy outdoes that of any other
available technique, are useful data which allow a comparison between theory
and experiment in the normal phase of the organic conductors.

</DOC>
<DOC>
<DOCNO> 69186 </DOCNO>
Positivity constraints and flavor dependence of higher twists


  The positivity bound for the transverse asymmetry $A_2$ may be improved and
applied for each quark flavor separately. We use it to test the consistency of
twist-two approximation for the transverse spin-dependent ($g_T$) and the
longitudinal spin-averaged ($F_L$) structure functions. While it is satisfied
in the case of $u$ quarks, it might be violated for $d$ quarks in a region of
moderate $x$ because of its negative polarization. We attribute this
inconsistency to a stronger twist-three contribution, whose existence found by
the QCD sum rule method is a long-standing puzzle.

</DOC>
<DOC>
<DOCNO> 10417 </DOCNO>
Ideal gas in nonextensive optimal Lagrange multipliers formalism


  Based on the prescription termed the optimal Lagrange multipliers formalism
for extremizing the Tsallis entropy indexed by q, it is shown that key aspects
of the treatment of the ideal gas problem are identical in both the
nonextensive and extensive cases.

</DOC>
<DOC>
<DOCNO> 151562 </DOCNO>
The FSUSY Hamiltonian in the connexion with the Chern-Simons gauge


  On the two-dimensional lattice, the construction of anyonic operators and its
algebras is discussed. Thus, the fractional supersymetry (FSUSY) and the
associated FSUSY Hamiltonian basing on the quonic anyons are recalled. Its
particular case for bosonic anyon and fermionic anyon is given. The FSUSY
Hamiltonian in the connexion with the Chern-Simons gauge theory is constructed.

</DOC>
<DOC>
<DOCNO> 120338 </DOCNO>
The origin of runaway stars


  Milli-arcsecond astrometry provided by Hipparcos and by radio observations
makes it possible to retrace the orbits of some of the nearest runaway stars
and pulsars to determine their site of origin. The orbits of the runaways AE
Aurigae and mu Columbae and of the eccentric binary iota Orionis intersect each
other about 2.5 Myr ago in the nascent Trapezium cluster, confirming that these
runaways were formed in a binary-binary encounter. The path of the runaway star
zeta Ophiuchi intersects that of the nearby pulsar PSR J1932+1059, about 1 Myr
ago, in the young stellar group Upper Scorpius. We propose that this neutron
star is the remnant of a supernova that occurred in a binary system which also
contained zeta Oph, and deduce that the pulsar received a kick velocity of
about 350 km/s in the explosion. These two cases provide the first specific
kinematic evidence that both mechanisms proposed for the production of runaway
stars, the dynamical ejection scenario and the binary-supernova scenario,
operate in nature.

</DOC>
<DOC>
<DOCNO> 117168 </DOCNO>
Pressure-volume-temperature equation of state of MgSiO3 perovskite from


  The composition of the lower mantle can be investigated by examining
densities and seismic velocities of compositional models as functions of depth.
In order to do this it is necessary to know the volumes and thermoelastic
properties of the compositional constituents under lower mantle conditions. We
determined the thermal equation of state (EOS) of MgSiO3 perovskite using the
nonempirical variational induced breathing (VIB) interatomic potential with
molecular dynamics simulations at pressures and temperatures of the lower
mantle. We fit our pressure-volume-temperature results to a thermal EOS of the
form P(V,T) = P0(V,T0) + Delta Pth(T), where T0 = 300 K and P0 is the
isothermal Universal EOS. The thermal pressure Delta Pth can be represented by
a linear relationship Delta Pth = a + b T. We find V0 = 165.40 A^3, KT0 = 273
GPa, K'T0 = 3.86, a = -1.99 GPa, and b = 0.00664 GPa K^-1 for pressures of
0-140 GPa and temperatures of 300-3000 K. By fixing V0 to the experimentally
determined value of 162.49 A^3 and calculating density and bulk sound velocity
profiles along a lower mantle geotherm we find that the lower mantle cannot
consist solely of (Mg,Fe)SiO3 perovskite with XMg ranging from 0.9-1.0. Using
pyrolitic compositions of 67 vol % perovskite (XMg = 0.93-0.96) and 33 vol %
magnesiowustite (XMg = 0.82-0.86), however, we obtained density and velocity
profiles that are in excellent agreement with seismological models for a
reasonable geotherm.

</DOC>
<DOC>
<DOCNO> 12773 </DOCNO>
Electron-phonon interaction on bundled structures: static and transport


  We study the small-polaron problem of a single electron interacting with the
lattice for the Holstein model in the adiabatic limit on a comb lattice, when
the electron-phonon interaction acts only on the base sites. The ground state
properties can be easily deduced from the ones of a linear chain with an
appropriate rescaling of the coupling constant. On the other hand, the
dynamical properties, that involve the complete spectrum of the system, present
an "exotic" behavior. In the weak coupling limit the Drude weight
(zero-frequency conductivity) is enhanced with respect to its free-case value,
contrary to the linear chain case, where for every finite value one has a
suppression of the Drude peak. More interestingly, the loss of coherent
electron motion and the polaronic localization of the carrier occurs for
different coupling values. Thus for intermediate coupling, a novel phase
appears with large kinetic energy and no coherent motion.

</DOC>
<DOC>
<DOCNO> 116312 </DOCNO>
Bethe logarithms for the 1 singlet S, 2 singlet S and 2 triplet S states


  We have computed the Bethe logarithms for the 1 singlet S, 2 singlet S and 2
triplet S states of the helium atom to about seven figure-accuracy using a
generalization of a method first developed by Charles Schwartz. We have also
calculated the Bethe logarithms for the helium-like ions of Li, Be, O and S for
all three states to study the 1/Z behavior of the results. The Bethe logarithm
of H minus was also calculated with somewhat less accuracy. The use of our
Bethe logarithms for the excited states of neutral helium, instead of those
from Goldman and Drake's first-order 1/Z-expansion, reduces by several orders
of magnitude the discrepancies between the theoretically calculated and
experimentally measured ionization potentials of these states.

</DOC>
<DOC>
<DOCNO> 71623 </DOCNO>
Leptogenesis and neutrino parameters


  We calculate the baryonic asymmetry of the universe in the
baryogenesis-via-leptogenesis framework, assuming first a quark-lepton symmetry
and then a charged-neutral lepton symmetry. We match the results with the
experimentally favoured range. In the first case all the oscillation solutions
to the solar neutrino problem, except the large mixing matter solution, can
lead to the allowed range, but with fine tuning of the parameters. In the
second case the general result is quite similar. Some related theoretical hints
are discussed.

</DOC>
<DOC>
<DOCNO> 118331 </DOCNO>
Dithering Strategies for Efficient Self-Calibration of Imaging Arrays


  With high sensitivity imaging arrays, accurate calibration is essential to
achieve the limits of detection of space observatories. One can simultaneously
extract information about the scene being observed and the calibration
properties of the detector and imaging system from redundant dithered images of
a scene. There are large differences in the effectiveness of dithering
strategies for allowing the separation of detector properties from sky
brightness measurements. In this paper, we quantify these differences by
developing a figure of merit (FOM) for dithering procedures based on their
usefulness for allowing calibration on all spatial scales. The figure of merit
measures how well the gain characteristics of the detector are encoded in the
measurements, and is independent of the techniques used to analyze the data.
Patterns similar to the antenna arrangements of radio interferometers with good
u-v plane coverage, are found to have good figures of merit. We present
patterns for both deep surveys of limited sky areas and for shallow surveys. By
choosing a strategy that encodes the calibration in the observations in an
easily extractable way, we enhance our ability to calibrate our detector
systems and to reach the ultimate limits of sensitivity which are required to
achieve the promise of many missions.

</DOC>
<DOC>
<DOCNO> 120278 </DOCNO>
Electron Positron Annihilation Radiation from SgrA East at the Galactic


  Maps of the Galactic electron-positron annihilation radiation show evidence
for three distinct and significant features: (1) a central bulge source, (2)
emission in the Galactic plane, and (3) an enhancement of emission at positive
latitudes above the Galactic Center. In this paper, we explore the possibility
that Sgr A East, a very prominent radio structure surrounding the Galactic
nucleus, may be a significant contributer to the central bulge feature. The
motivation for doing so stems from a recently proposed link between this radio
object and the EGRET gamma-ray source 2EG J1746-2852. If this association is
correct, then Sgr A East is also expected to be a source of copious positron
production. The results presented here show that indeed Sgr A East must have
produced a numerically significant population of positrons, but also that most
of them have not yet had sufficient time to thermalize and annihilate. As such,
Sgr A East by itself does not appear to be the dominant current source of
annihilation radiation, but it will be when the positrons have cooled
sufficiently and they have become thermalized. This raises the interesting
possibility that the bulge component may be due to the relics of earlier
explosive events like the one that produced Sgr A East.

</DOC>
<DOC>
<DOCNO> 170251 </DOCNO>
Quantum mechanical histories and the Berry phase


  We elaborate on the distinction between geometric and dynamical phase in
quantum theory and show that the former is intrinsically linked to the quantum
mechanical probabilistic structure. In particular, we examine the appearance of
the Berry phase in the consistent histories scheme and establish that it is the
basic building block of the decoherence functional.
 These results are consequences of the novel temporal structure of
histories-based theories.

</DOC>
<DOC>
<DOCNO> 174588 </DOCNO>
Review of SIS Experimental Results on Strangeness


  >A review of meson emission in heavy ion collisions at incident energies
around 1 -- 2 $A\cdot$GeV is presented. It is shown how the shape of the
spectra and the various particle yields vary with system size, with centrality
and with incident energy. A statistical model assuming thermal and chemical
equilibrium and exact strangeness conservation (i.e. strangeness conservation
per collision) explains most of the observed features.
  Emphasis is put onto the study of $K^+$ and $K^-$ emission. In the framework
of this statistical model it is shown that the experimentally observed equality
of $K^+$ and $K^-$ rates at threshold corrected energies $\sqrt{s} -
\sqrt{s_{th}}$ is due to a crossing of two excitation functions. Furthermore,
the independence of the $K^+$ to $K^-$ ratio on the number of participating
nucleons observed between 1 and 10 $A\cdot$GeV is consistent with this model.
The observed flow effects are beyond the scope of this model.

</DOC>
<DOC>
<DOCNO> 151322 </DOCNO>
Deformations of Topological Open Strings


  Deformations of topological open string theories are described, with an
emphasis on their algebraic structure. They are encoded in the mixed
bulk-boundary correlators. They constitute the Hochschild complex of the open
string algebra -- the complex of multilinear maps on the boundary Hilbert
space. This complex is known to have the structure of a Gerstenhaber algebra
(Deligne theorem), which is also found in closed string theory. Generalising
the case of function algebras with a B-field, we identify the algebraic
operations of the bulk sector, in terms of the mixed correlators. This gives a
physical realisation of the Deligne theorem. We translate to the language of
certain operads (spaces of d-discs with gluing) and d-algebras, and comment on
generalisations, notably to the AdS/CFT correspondence. The formalism is
applied to the topological A- and B-models on the disc.

</DOC>
<DOC>
<DOCNO> 8248 </DOCNO>
Conformal Dynamics of Fractal Growth Patterns Without Randomness


  Many models of fractal growth patterns (like Diffusion Limited Aggregation
and Dielectric Breakdown Models) combine complex geometry with randomness; this
double difficulty is a stumbling block to their elucidation. In this paper we
introduce a wide class of fractal growth models with highly complex geometry
but without any randomness in their growth rules. The models are defined in
terms of deterministic itineraries of iterated conformal maps, automatically
generating the global conformal function which maps the exterior of the unit
circle to the exterior of a n-particle growing aggregate. The complexity of the
evolving interfaces is fully contained in the deterministic dynamics of the
conformal map. We focus attention to a class of growth models in which the
itinerary is quasiperiodic. Such itineraries can be approached via a series of
rational approximants. The analytic power gained is used to introduce a scaling
theory of the fractal growth patterns. We explain the mechanism for the
fractality of the clusters and identify the exponent that determines the
fractal dimension.

</DOC>
<DOC>
<DOCNO> 80993 </DOCNO>
Non-perturbative Renormalization in Lattice Field Theory


  I review the strategies which have been developped in recent years to solve
the non-perturbative renormalization problem in lattice field theories.
Although the techniques are general, the focus will be on applications to
lattice QCD. I discuss the momentum subtraction and finite volume schemes, and
their application to scale dependent renormalizations. The problem of finite
renormalizations is illustrated with the example of explicit chiral symmetry
breaking, and I give a short status report concerning Symanzik's improvement
programme to O($a$).

</DOC>
<DOC>
<DOCNO> 13878 </DOCNO>
Hubbard ladders in a magnetic field


  The behavior of a two leg Hubbard ladder in the presence of a magnetic field
is studied by means of Abelian bosonization. We predict the appearance of a new
(doping dependent) plateau in the magnetization curve of a doped 2-leg spin
ladder in a wide range of couplings. We also discuss the extension to N-leg
Hubbard ladders.

</DOC>
<DOC>
<DOCNO> 99658 </DOCNO>
Multifractal Spectrum and Thermodynamical Formalism of the Farey Tree


  The task of comparing the Hausdorff spectrum, the computational spectrum, and
the Legendre spectrum of a fractal set endowed with a probability measure, was
tackled by several authors - Cawley and Mauldin, Riedi and Mandelbrot, among
others. For self-similar measures all three spectra coincide. We compare these
spectra for the hyperbolic measure (inducing the Farey Tree partition),
fundamentally different from the self-similar one.

</DOC>
<DOC>
<DOCNO> 68441 </DOCNO>
EDM-free supersymmetric CP violation with non-universal soft terms


  Non-universality in the soft breaking terms is a common feature in most
superstring inspired SUSY models. This property is required to obtain sizeable
CP violation effects from SUSY and, on the other hand, can be used to avoid the
Electric Dipole Moment constraints. We take advantage of these qualities and
explore a class of SUSY models based on type I string theory where scalar
masses, gaugino masses and trilinear couplings are non-universal. In this
framework, we show that, in the presence of large SUSY phases, the bounds on
the Electric Dipole Moments can be controled without fine-tuning. At the same
time, we find that these phases, free from EDM constraints, lead to large
contributions to the observed CP phenomena in Kaon system and, in particular,
to direct CP violation in epsilon'/epsilon.

</DOC>
<DOC>
<DOCNO> 152282 </DOCNO>
The Spectrum of N=3 String Theory on AdS_3 x G/H


  We continue the study of string theory on AdS_3 x SU(3)/U(1) and AdS_3 x
SO(5)/SO(3). We compute the spacetime spectrum of the N=3 supersymmetric dual
CFT using worldsheet techniques. The spectrum of chiral primaries coincides for
the two models. Unlike N=4 theories, the building block of the symmetric
product in spacetime (corresponding to a single long string) is not by itself
in the moduli space of a symmetric product.

</DOC>
<DOC>
<DOCNO> 179030 </DOCNO>
Renormalization of the weak hadronic current in the nuclear medium


  The renormalization of the weak charge-changing hadronic current as a
function of the reaction energy release is studied at the nucleonic level. We
have calculated the average quenching factors for each type of current (vector,
axial vector and induced pseudoscalar). The obtained quenching in the axial
vector part is, at zero momentum transfer, 19% for the sd shell and 23% in the
fp shell. We have extended the calculations also to heavier systems such as
$^{56}$Ni and $^{100}$Sn, where we obtain stronger quenchings, 44% and 59%,
respectively. Gamow--Teller type transitions are discussed, along with the
higher order matrix elements. The quenching factors are constant up to roughly
60 MeV momentum transfer. Therefore the use of energy-independent quenching
factors in beta decay is justified. We also found that going beyond the zeroth
and first order operators (in inverse nucleon mass) does not give any
substantial contribution. The extracted renormalization to the ratio $C_P/C_A$
at q=100 MeV is -3.5%, -7.1$%, -28.6%, and +8.7% for mass 16, 40, 56, and 100,
respectively.

</DOC>
<DOC>
<DOCNO> 101899 </DOCNO>
Erratum: Some Remarks on the Cohomology of Krichever-Novikov Algebras


  We discovered that only a weakened version of the main lemma is true. We
state the right version, and the remaining open problem: Is it possible to
approximate holomorphic vector fields (or more generally, sections in a line
bundle) on an open Riemann surface of finite type (i.e. a compact one without a
finite number of points) by meromorphic vector fields (where the poles are
supposed to be in the distinguished points) ? We know that this is true for
functions.

</DOC>
<DOC>
<DOCNO> 117865 </DOCNO>
The Space Density of Primordial Gas Clouds near Galaxies and Groups and


  The Arecibo HI Strip Survey probed the halos of ~300 cataloged galaxies and
the environments of ~14 groups with sensitivity to neutral hydrogen masses >
10^7 M_sun. The survey detected no objects with properties resembling the High
Velocity Clouds (HVCs) associated with the Milky Way or Local Group. If the
HVCs were typically M_HI=10^{7.5} M_sun objects distributed throughout groups
and galaxy halos at distances of 1 Mpc, the survey should have made ~70 HVC
detections in groups and ~250 detections around galaxies. The null detection
implies that HVCs are deployed at typical distances of <200 kpc from the
galaxies or group barycenters. If the clouds are in virial equilibrium, their
average dark matter fraction must be 98% or higher.

</DOC>
<DOC>
<DOCNO> 151875 </DOCNO>
BFFT quantization and dynamical solutions of a fluid field theory


  We study a field theory formulation of a fluid mechanical model. We implement
the Hamiltonian formalism by using the BFFT conjecture in order to build a
gauge invariant fluid field theory. We also generalize previous known classical
dynamical field solutions for the fluid model.

</DOC>
<DOC>
<DOCNO> 100784 </DOCNO>
Non-commutative Bloch theory


  For differential operators which are invariant under the action of an abelian
group Bloch theory is the preferred tool to analyze spectral properties. By
shedding some new non-commutative light on this we motivate the introduction of
a non-commutative Bloch theory for elliptic operators on Hilbert C*-modules. It
relates properties of C*-algebras to spectral properties of module operators
such as band structure, weak genericity of cantor spectra, and absence of
discrete spectrum. It applies e.g. to differential operators invariant under a
projective group action, such as Schroedinger, Dirac and Pauli operators with
periodic magnetic field, as well as to discrete models, such as the almost
Matthieu equation and the quantum pendulum.

</DOC>
<DOC>
<DOCNO> 13401 </DOCNO>
Two-Dimensional Tensor Product Variational Formulation


  We propose a numerical self-consistent method for 3D classical lattice
models, which optimizes the variational state written as two-dimensional
product of tensors. The variational partition function is calculated by the
corner transfer matrix renormalization group (CTMRG), which is a variant of the
density matrix renormalization group (DMRG). Numerical efficiency of the method
is observed via its application to the 3D Ising model.

</DOC>
<DOC>
<DOCNO> 120597 </DOCNO>
From kinematics to dynamics in thin galactic disk


  We present a method for recovering the distribution functions of edge-on thin
axisymmetric disks directly from their observable kinematic properties. The
most generally observable properties of such a stellar system are the
line-of-sight velocity distributions of the stars at different projected radii
along the galaxy. If the gravitational potential is known, then the general
two-integral distribution function can be reconstructed using the shapes of the
high-velocity tails of these line-of-sight distributions. If the wrong
gravitational potential is adopted, then a distribution function can still be
constructed using this technique, but the low-velocity parts of the observed
velocity distributions will not be reproduced by the derived dynamical model.
Thus, the gravitational potential is also tightly constrained by the observed
kinematics.

</DOC>
<DOC>
<DOCNO> 13611 </DOCNO>
Critical behavior of the long-range Ising chain from the largest-cluster


  Monte Carlo simulations of the 1D Ising model with ferromagnetic interactions
decaying with distance $r$ as $1/r^{1+\sigma}$ are performed by applying the
Swendsen-Wang cluster algorithm with cumulative probabilities. The critical
behavior in the non-classical critical regime corresponding to $0.5 <\sigma <
1$ is derived from the finite-size scaling analysis of the largest cluster.

</DOC>
<DOC>
<DOCNO> 100144 </DOCNO>
Quantum Zeno Dynamics


  The evolution of a quantum system undergoing very frequent measurements takes
place in a subspace of the total Hilbert space (quantum Zeno effect). The
dynamical properties of this evolution are investigated and several examples
are considered.

</DOC>
<DOC>
<DOCNO> 70973 </DOCNO>
Heavy Quark Production in $\gamma\gamma$ Collisions


  New results on inclusive heavy quark production in gamma gamma collisions are
presented. Charm and bottom production are investigated at LEP II energies by
the experiments ALEPH, DELPHI, L3, and OPAL. The total and differential cross
sections for charm quarks are measured. The contributions from the direct and
single-resolved processes are separated and their fractions quantified. More
detailed studies, such as the dependence of the cross section on the two-photon
centre-of-mass energy and the charm structure function F^2_gamma,c, are
reported. The inclusive bottom cross section is presented. Measurements are
compared to next-to-leading order calculations.

</DOC>
<DOC>
<DOCNO> 178851 </DOCNO>
Nuclear processes in magnetic fusion reactors with polarized fuel


  We consider the processes $d +d \to n +{^3He}$, $d +{^3He} \to p +{^4He}$, $d
+{^3H} \to n +{^4He}$, ${^3He} +{^3He}\to p+p +{^4He}$, ${^3H} +{^3He}\to d
+{^4He}$, with particular attention for applications in fusion reactors. After
a model independent parametrization of the spin structure of the matrix
elements for these processes at thermal colliding energies, in terms of partial
amplitudes, we study polarization phenomena in the framework of a formalism of
helicity amplitudes. The strong angular dependence of the final nuclei and of
the polarization observables on the polarizations of the fuel components can be
helpful in the design of the reactor shielding, blanket arrangement etc..We
analyze also the angular dependence of the neutron polarization for the
processes $\vec d +\vec d \to n +{^3He}$ and $\vec d +\vec {^3H} \to n
+{^4He}$.

</DOC>
<DOC>
<DOCNO> 118086 </DOCNO>
Models of Wave Supported Clumps in Giant Molecular Clouds


  We present plane-parallel equilibrium models of molecular clumps that are
supported by Alfven waves damped by the linear process of ion-neutral friction.
We used a WKB approximation to treat the inward propagation of waves and
adopted a realistic ionization structure influenced by dissociation and
ionization due to photons of external origin. The model clumps are larger and
less centrally condensed than those obtained for an assumed ionization
structure, used in some previous studies, that is more appropriate for dark
regions.

</DOC>
<DOC>
<DOCNO> 169622 </DOCNO>
Consistent Quantum Realism: A Reply to Bassi and Ghirardi


  A recent claim by Bassi and Ghirardi that the consistent (decoherent)
histories approach cannot provide a realistic interpretation of quantum theory
is shown to be based upon a misunderstanding of the single-framework rule: they
have replaced the correct rule with a principle which directly contradicts it.
It is their assumptions, not those of the consistent histories approach, which
lead to a logical contradiction.

</DOC>
<DOC>
<DOCNO> 39876 </DOCNO>
Determination of the pattern of neutrino masses at a Neutrino Factory


  We study the precision to which the sign of \delta m_{32}^2 can be determined
at a neutrino factory, as a function of stored energies and baselines. This is
done by simultaneously fitting the channels \nu_\mu \to \nu_\mu$, \bar\nu_e \to
\bar\nu_\mu from \mu^- decays and the channels \bar\nu_\mu \to \bar\nu_\mu,
\nu_e \to \nu_\mu from \mu^+ decays. We investigate the sensitivity reach in
the parameter \sin^22\theta_{13} to which one can determine the sign of \delta
m_{32}^2 to 3 standard deviations as a function of the baseline length and
magnitude of \delta m_{32}^2 with a 20 GeV muon storage ring. We find that for
baselines longer than 2000 km, the sign of \delta m^2_{32} can be determined
for \sin^22\theta_{13} down to the 10^{-3} level with 10^{20} decays of 20 GeV
muons.

</DOC>
<DOC>
<DOCNO> 69917 </DOCNO>
10^20 eV Cosmic-Ray and Particle Physics with Kilometer-Scale Neutrino


  We show that a kilometer-scale neutrino observatory, though optimized for TeV
to PeV energy, is sensitive to the neutrinos associated with super-EeV sources.
These include super-heavy relics, neutrinos associated with the Greisen cutoff,
and topological defects which are remnant cosmic structures associated with
phase transitions in grand unified gauge theories. It is a misconception that
new instruments optimized to EeV energy are required to do this important
science. Because kilometer-scale neutrino telescopes can reject atmospheric
backgrounds by establishing the very high energy of the signal events, they
have sensitivity over the full solid angle, including the horizon where most of
the signal is concentrated. This is important because up-going neutrino-induced
muons, routinely considered in previous calculations, are absorbed by the
Earth.

</DOC>
<DOC>
<DOCNO> 178561 </DOCNO>
Foundations of self-consistent particle-rotor models and of


  The Kerman-Klein formulation of the equations of motion for a nuclear shell
model and its associated variational principle are reviewed briefly. It is then
applied to the derivation of the self-consistent particle-rotor model and of
the self-consistent cranking model, for both axially symmetric and triaxial
nuclei. Two derivations of the particle-rotor model are given. One of these is
of a form that lends itself to an expansion of the result in powers of the
ratio of single-particle angular momentum to collective angular momentum, that
is essentual to reach the cranking limit. The derivation also requires a
distinct, angular-momentum violating, step. The structure of the result implies
the possibility of tilted-axis cranking for the axial case and full
three-dimensional cranking for the triaxial one. The final equations remain
number conserving. In an appendix, the Kerman-Klein method is developed in more
detail, and the outlines of several algorithms for obtaining solutions of the
associated non-linear formalism are suggested.

</DOC>
<DOC>
<DOCNO> 151048 </DOCNO>
Symmetry and Covariance of Non-relativistic Quantum Mechanics


  On the basis of a 5-dimensional form of space-time transformations
non-relativistic quantum mechanics is reformulated in a manifestly covariant
manner. The resulting covariance resembles that of the conventional
relativistic quantum mechanics.

</DOC>
<DOC>
<DOCNO> 10642 </DOCNO>
Temporal and spatial correlations in a visco-elastic model of


  We study the temporal and spatial correlations in a one-dimensional model of
a heterogeneous fault zone, in the presence of visco-elastic effects. As a
function of dynamical weakening and of dissipation, the system exhibits three
different "phases" : one in which there are no time correlations between the
events, a second, in which there are ``Omori's law'' type temporal
correlations, and a third, runaway phase with quasiperiodic system size events.

</DOC>
<DOC>
<DOCNO> 151360 </DOCNO>
Concepts in Gauge Theory Leading to Electric--Magnetic Duality


  Gauge theory, which is the basis of all particle physics, is itself based on
a few fundamental concepts, the consequences of which are often as beautiful as
they are deep. In this short lecture course I shall try to give an introduction
to these concepts, both from the physical and mathematical points of view. Then
I shall show how these considerations lead to a nonabelian generalization of
the well-known electric--magnetic duality in electromagnetism. I shall end by
sketching some of the many consequences in quantum field theory that this
duality engenders in particle physics.
  These are notes from a lecture course given in the Summer School on {\em
Geometric Methods in Quantum Field Theory}, Villa de Leyva, Colombia, July
1999, as well as a series of graduate lectures given in Oxford in Trinity Term
of 1999 and 2000.

</DOC>
<DOC>
<DOCNO> 117662 </DOCNO>
Gas Streams and Spiral Structure in the Milky Way


  The observed gas dynamics in the Milky Way can only be explained by a bar in
the galactic center. Such a bar is directly visible in the near-IR maps of the
bulge, where it causes a distinctive asymmetric light distribution pattern.
Another large-scale structure is the grand-design 4-arm spiral pattern, most
clearly observed in the spatial distribution of molecular gas and HII-regions.
   In order to model the observed gas flow structure, we constructed a model
for the stellar mass distribution. For the inner 5 $\kpc$ we used the 3D
deprojected near-IR light distribution, as observed by the COBE/DIRBE
experiment, and added an analytical disk model outside the box as well as a
halo model. With this frozen mass distribution, we computed the stationary gas
flow for various deprojection parameters and pattern speeds. For all reasonable
parameter choices, we obtain a 4-armed spiral pattern, which can be matched to
the observed spiral arms.
   In the bar region, our model can explain the non-circular motion visible in
the terminal velocity curve as well as part of the forbidden velocities. Inside
the corotation, we also find 4 spiral arms, the nearest arm corresponds to the
3-kpc-arm, although only qualitatively. The missing southern 3-kpc-arm at the
far end of the galaxy is explained by running parallel to another arm. Close to
the center, we find gas on circular orbits forming a disk. Such a disk has been
observed in emission of the CS molecule, however only part of the disk appears
to be occupied by dense enough gas to be traced by CS. Further we compare our
model to the distribution of OH/IR stars in the inner galaxy.

</DOC>
<DOC>
<DOCNO> 71479 </DOCNO>
Magnetic moment of the two-particle bound state in quantum


  We have formulated the quasipotential method for the calculation of the
relativistic and radiative corrections to the magnetic moment of the
two-particle bound state in the case of particles with arbitrary spin. It is
shown that the g-factors of bound particles contain $O(\alpha^2)$ terms
depending on the particle spin. Numerical values for the g-factors of the
electron in the hydrogen atom and deuterium are obtained.

</DOC>
<DOC>
<DOCNO> 69700 </DOCNO>
Out-of-equilibrium Photon Production from Disoriented Chiral Condensates


  We study the production of photons through the non-equilibrium relaxation of
a disoriented chiral condensate. We propose that to search for non-equilibrium
photons in the direct photon measurements of heavy-ion collisions can be a
potential test of the formation of disoriented chiral condensates.

</DOC>
<DOC>
<DOCNO> 122395 </DOCNO>
Isotropization of Ultra-High Energy Cosmic Ray Arrival Directions by


  The isotropy in the ultra high energy cosmic ray (UHECR) flux observed by
Yakutsk and AGASA experiments, is a very strong constraint to production and
propagation models alike. Most of the scenarios proposed in the literature
should produce a sizable anisotropy as either extragalactic luminous or dark
matter is normally associated with the invoked particle sources. We explore the
possibility that the magnetic fields in fossil cocoons of former radio galaxies
-- so called {\it radio ghosts} -- are able to scatter UHECR in the
intergalactic medium giving rise to the observed isotropy. We show, through
numerical simulations, under which conditions this process can be operative and
the magnitude of the effect. We further demonstrate, that if radio ghosts mix
with the ambient medium, they might be able to produce the observed magnetic
fields in clusters of galaxies. In the case of mixing, the UHECR isotropization
would be even stronger than in our conservative estimates.

</DOC>
<DOC>
<DOCNO> 119400 </DOCNO>
Eclipsing Binaries as Astrophysical Laboratories: Internal Structure,


  New photometric solutions have been carried out on the important eccentric
eclipsing system V380 Cygni (B1.5II-III + B2V) from UBV differential
photoelectric photometry obtained by us. The photometric elements obtained from
the analysis of the light curves have been combined with the spectroscopic
solution recently published by Popper & Guinan and have led to the physical
properties of the system components. The effective temperature of the stars has
been determined by fitting IUE UV spectrophotometry to Kurucz model atmospheres
and compared with other determinations from broad-band and intermediate-band
standard photometry. The values of mass, absolute radius, and effective
temperature, for the primary and secondary stars are: 11.1+/-0.5 Mo, 14.7+/-0.2
Ro, 21350+/-400 K, and 6.95+/-0.25 Mo, 3.74+/-0.07 Ro, 20500+/-500 K,
respectively. In addition, a re-determination of the system's apsidal motion
rate has been done from the analysis of 12 eclipse timings obtained from 1923
to 1995. Using stellar structure and evolutionary models with modern input
physics, tests on the extent of convection in the core of the more massive star
of the system have been carried out. Both the analysis of the log g-log Teff
diagram and the apsidal motion study indicate a star with a larger convective
core, and thus more centrally condensed, than currently assumed. This has been
quantified in form of an overshooting parameter with a value of 0.6+/-0.1.
Finally, the tidal evolution of the system (synchronization and circularization
times) has also been studied.

</DOC>
<DOC>
<DOCNO> 10346 </DOCNO>
Comment on "Critical currents in ballistic two-dimensional InAs-based


  In ballistic Josephson junctions the experimentally observed
iv-characteristics deviate from the theoretically predicted behaviour.
Recently, Heida et al. Phys. Rev. B 60, 13135 (1999) discussed this problem and
offered an explanation for the discrepancy. Considering this explanation,
several contradictions to the authors' data as well as to other publications
are shown.

</DOC>
<DOC>
<DOCNO> 67761 </DOCNO>
Azimuthal Angle Distribution in $B \to K^* (\to K \pi) \ell^+ \ell^- $


  We present the angular distribution of the rare B decay, $B \to K^* (\to K
\pi) \ell^+ \ell^-$. By studying the azimuthal angle distribution in the low
invariant mass region of dileptons, we can probe new physics effects
efficiently. In particular, this distribution is found to be quite sensitive to
the ratio of the contributions from two independent magnetic moment operators,
which also contribute to $B \to K^* \gamma$. Therefore, our method can be very
useful when new physics is introduced without changing the total decay rate of
the $b \to s \gamma$. The angular distributions are compared with the
predictions of the standard model, and are shown for the cases when the
afore-mentioned ratio is different from the standard model prediction.

</DOC>
<DOC>
<DOCNO> 84148 </DOCNO>
On stationary vacuum solutions to the Einstein equations


  It is proved that the only geodesically complete stationary vacuum solution
of the Einstein equations is the empty Minkowski space, or a quotient of it by
a discrete group of isometries, generalizing a classical result of
Lichnerowicz. In addition, we obtain an apriori bound on the curvature of
stationary vacuum solutions away from the boundary or horizon.

</DOC>
<DOC>
<DOCNO> 39852 </DOCNO>
Determination of the strange quark mass from Cabibbo-suppressed tau


  We present an analysis of the m_s^2-corrections to Cabibbo-suppressed tau
lepton decays employing contour improved resummation within an effective scheme
which is an essential new feature as compared to previous analyses. The whole
perturbative QCD dynamics of the tau-system is described by the beta-function
of the effective coupling constant and by two gamma-functions for the effective
mass parameters of the strange quark in different spin channels. We analyze the
stability of our results with regard to high-order terms in the perturbative
expansion of the renormalization group functions. A numerical value for the
strange quark mass in the MS scheme is extracted m_s(M_\tau)=130\pm 27_{exp}\pm
9_{th} MeV. After running to the scale 1 GeV this translates into m_s(1
GeV)=176 \pm 37_{exp}\pm 13_{th} MeV.

</DOC>
<DOC>
<DOCNO> 101978 </DOCNO>
Rational obstruction theory and rational homotopy sets


  We develop an obstruction theory for homotopy of homomorphisms f,g : M -> N
between minimal differential graded algebras. We assume that M = Lambda V has
an obstruction decomposition given by V = V_0 oplus V_1 and that f and g are
homotopic on Lambda V_0. An obstruction is then obtained as a vector space
homomorphism V_1 -> H^*(N). We investigate the relationship between the
condition that f and g are homotopic and the condition that the obstruction is
zero. The obstruction theory is then applied to study the set of homotopy
classes [M, N]. This enables us to give a fairly complete answer to a
conjecture of Copeland-Shar on the size of the homotopy set [A,B] when A and B
are rational spaces. In addition, we give examples of minimal algebras (and
hence of rational spaces) that have few homotopy classes of self-maps.

</DOC>
<DOC>
<DOCNO> 10803 </DOCNO>
Self-organization in systems of self-propelled particles


  We investigate a discrete model consisting of self-propelled particles that
obey simple interaction rules. We show that this model can self-organize and
exhibit coherent localized solutions in one- and in two-dimensions.In
one-dimension, the self-organized solution is a localized flock of finite
extent in which the density abruptly drops to zero at the edges.In
two-dimensions, we focus on the vortex solution in which the particles rotate
around a common center and show that this solution can be obtained from random
initial conditions, even in the absence of a confining boundary. Furthermore,
we develop a continuum version of our discrete model and demonstrate that the
agreement between the discrete and the continuum model is excellent.

</DOC>
<DOC>
<DOCNO> 169706 </DOCNO>
On The Significance of Bell's Locality Condition


  Reviewing the general representation of a stochastic local hidden variables
theory in the context of an ideal Bohm's version of the EPR experiment, we show
explicitly that the violation of Bell's locality condition is due to the
assumption of ``outcome independence'' at the hidden variables level. Also, we
show that if we introduce determinism, the assumption of outcome independence
will be allowed.

</DOC>
<DOC>
<DOCNO> 120531 </DOCNO>
Pre-Main Sequence models for low-mass stars and brown dwarfs


  We present evolutionary models for low mass stars and brown dwarfs ($m \le
1.2 \msol$) based on recent improvement of the theory: equation of state,
atmosphere models, ... We concentrate on early evolutionary phases from the
initial deuterium burning phase to the zero-age Main Sequence. Evolutionary
models for young brown dwarfs are also presented. We discuss the uncertainties
of the present models. We analyse the difficulties arising when comparing
models with observations for very young objects, in particular concerning the
problem of reddening.

</DOC>
<DOC>
<DOCNO> 170076 </DOCNO>
Coherent states for the hydrogen atom


  We construct a system of coherent states for the hydrogen atom that is
expressed in terms of elementary functions. Unlike to the previous attempts in
this direction, this system possesses the properties equivalent to the most of
those for the harmonic oscillator, with modifications due to the character of
the problem.

</DOC>
<DOC>
<DOCNO> 9217 </DOCNO>
Pinning phenomena in the Ginzburg-Landau Model of Superconductivity


  We study the Ginzburg-Landau energy of superconductors with a term $a_\ep$
modelling the pinning of vortices by impurities in the limit of a large
Ginzburg-Landau parameter $\kappa=1/\ep$. The function $a_\ep$ is oscillating
between 1/2 and 1 with a scale which may tend to 0 as $\kappa$ tends to
infinity.
  Our aim is to understand that in the large $\kappa$ limit, stable
configurations should correspond to vortices pinned at the minimum of $a_\ep$
and to derive the limiting homogenized free-boundary problem which arises for
the magnetic field in replacement of the London equation.
 The method and techniques that we use are inspired from those of
Sandier-Serfaty (in which the case $a_\ep \equiv 1$ was treated) and based on
energy estimates, convergence of measures and construction of approximate
solutions. Because of the term $a_\ep(x)$ in the equations, we also need
homogenization theory to describe the fact that the impurities, hence the
vortices, form a homogenized medium in the material.

</DOC>
<DOC>
<DOCNO> 118906 </DOCNO>
The X-ray Size-Temperature Relation for Intermediate Redshift Galaxy


  We present the first measurements of the X-ray size-temperature (ST) relation
in intermediate redshift (z~0.30) galaxy clusters. We interpret the local ST
relation (z~0.06) in terms of underlying scaling relations in the cluster dark
matter properties, and then we use standard models for the redshift evolution
of those dark matter properties to show that the ST relation does not evolve
with redshift. We then use ROSAT HRI observations of 11 clusters to examine the
intermediate redshift ST relation; for currently favored cosmological
parameters, the intermediate redshift ST relation is consistent with that of
local clusters. Finally, we use the ST relation and our evolution model to
measure angular diameter distances; with these 11 distances we evaluate
constraints on Omega_M and Omega_L which are consistent with those derived from
studies of Type Ia supernovae. The data rule out a model with Omega_M=1 and
Omega_L=0 with 2.5 sigma confidence. When limited to models where
Omega_M+Omega_L=1, these data are inconsistent with Omega_M=1 with 3 sigma
confidence.

</DOC>
<DOC>
<DOCNO> 122767 </DOCNO>
Cosmological Evolution of Linear Bias


  Using linear perturbation theory and the Friedmann-Lemaitre solutions of the
cosmological field equations, we derive analytically a second-order
differential equation for the evolution of the linear bias factor, b(z),
between the background matter and a mass-tracer fluctuation field. We find b(z)
to be a strongly dependent function of redshift in all cosmological models.
Comparing our analytical solution with the semi-analytic model of Mo & White,
which utilises the Press-Schechter formalism and the gravitationally induced
evolution of clustering, we find an extremely good agreement even at large
redshifts, once we normalize to the same bias value at two different epochs,
one of which is the present. Furthermore, our analytic b(z) function agrees
well with the outcome of N-body simulations even up to large redshifts.

</DOC>
<DOC>
<DOCNO> 10870 </DOCNO>
High-energy magnon dispersion and multi-magnon continuum in the


  We use quantum Monte Carlo simulations and numerical analytic continuation to
study high-energy spin excitations in the two-dimensional S=1/2 Heisenberg
antiferromagnet at low temperature. We present results for both the transverse
and longitudinal dynamic spin structure factor S(q,w) at q=(pi,0) and
(pi/2,pi/2). Linear spin-wave theory predicts no dispersion on the line
connecting these momenta. Our calculations show that in fact the magnon energy
at (pi,0) is 10% lower than at (pi/2,pi/2). We also discuss the transverse and
longitudinal multi-magnon continua and their relevance to neutron scattering
experiments.

</DOC>
<DOC>
<DOCNO> 99810 </DOCNO>
Higher homotopy groups of complements of complex hyperplane arrangements


  We generalize results of Hattori on the topology of complements of hyperplane
arrangements, from the class of generic arrangements, to the much broader class
of hypersolvable arrangements. We show that the higher homotopy groups of the
complement vanish in a certain combinatorially determined range, and we give an
explicit Z\pi_1-module presentation of \pi_p, the first non-vanishing higher
homotopy group. We also give a combinatorial formula for the \pi_1-coinvariants
of \pi_p.
  For affine line arrangements whose cones are hypersolvable, we provide a
minimal resolution of \pi_2, and study some of the properties of this module.
For graphic arrangements associated to graphs with no 3-cycles, the algorithm
for computing \pi_2 is purely combinatorial. The Fitting varieties associated
to \pi_2 may distinguish the homotopy 2-types of arrangement complements with
the same \pi_1, and the same Betti numbers in low degrees.

</DOC>
<DOC>
<DOCNO> 8774 </DOCNO>
The underdoped-overdoped transition in YBa_2Cu_3O_x


  Oxygen doping in metallic YBa_2Cu_3O_x induces quadrupolar "alpha-ortho'',
and breathing "beta-ortho" deformations of the CuO_2 planes. Breathing
beta-ortho deformations favour hybridizations of the pd sigma Cu3d_x^2-y^2 -
O2p_x,y with the pd pi Cu3d_x,z, 3d_y,z-O2p_z bands relaxing the confinement of
the carriers in the overdoped regime, x>6.95.

</DOC>
<DOC>
<DOCNO> 9795 </DOCNO>
Orbital-ordering-induced anomalous softening of the ferromagnetic spin


  Spin wave excitations were measured in the ferromagnetic phase of
Nd$_{1/2}$Sr$_{1/2}$MnO$_{3}$ by neutron scattering. This compound is located
in proximity to the A-type antiferromagnetic state, and it shows a clear
anisotropy and anomalous softening of the spin wave excitations. The softening
in the ferromagnetic phase is induced by the orbital ordering.

</DOC>
<DOC>
<DOCNO> 100576 </DOCNO>
Knotted Spheres and Graphs in Balls


  Given a properly embedded graph Gamma in a ball B and a punctured sphere
Sigma properly embedded in B - Gamma, we examine the conditions on Gamma that
are necessary to assure that Sigma is boundary parallel.

</DOC>
<DOC>
<DOCNO> 70587 </DOCNO>
Cosmological expansion on a dilatonic brane-world


  In this paper we study brane-world scenarios with a bulk scalar field, using
a covariant formalism to obtain a 4D Einstein equation via projection onto the
brane. We discuss, in detail, the effects of the bulk on the brane and how the
scalar field contribute to the gravitational effects. We also discuss choice of
conformal frame and show that the frame selected by the induced metric provides
a natural choice. We demonstrate our formalism by applying it to cosmological
scenarios of Randall-Sundrum and Horava-Witten type models. Finally we consider
the cosmology of models where the scalar field couples non-minimally to the
matter on the brane. This gives rise to a novel scenario where the universe
expands from a finite scale factor with an initial period of accelerated
expansion, thus avoiding the singularity and flatness problem of the standard
big bang model.

</DOC>
<DOC>
<DOCNO> 40510 </DOCNO>
Observation of Polarization in Bottomonium Production at sqrt(s)=38.8


  We present a measurement of the polarization observed for bottomonium states
produced in p-Cu collisions at sqrt(s)=38.8 GeV. The angular distribution of
the decay dimuons of the Upsilon(1S) state show no polarization at small xF and
pT but significant positive transverse production polarization for either pT >
1.8 GeV/c or for xF > 0.35. The Upsilon(2S+3S) unresolved states show a large
transverse production polarization at all values of xF and pT measured. These
observations are compared with an NRQCD calculation that predicts a transverse
polarization in bottomonium production arising from quark-antiquark fusion and
gluon-gluon fusion diagrams.

</DOC>
<DOC>
<DOCNO> 118418 </DOCNO>
WR146 - observing the OB-type companion


  We present new radio and optical observations of the colliding-wind system
WR146 aimed at understanding the nature of the companion to the Wolf-Rayet star
and the collision of their winds. The radio observations reveal emission from
three components: the WR stellar wind, the non-thermal wind-wind interaction
region and, for the first time, the stellar wind of the OB companion. This
provides the unique possibility of determining the mass-loss rate and terminal
wind velocity ratios of the two winds, independent of distance. Respectively,
these ratios are determined to be 0.20+/-0.06 and 0.56+/-0.17 for the
OB-companion star relative to the WR star. A new optical spectrum indicates
that the system is more luminous than had been believed previously. We deduce
that the ``companion'' cannot be a single, low luminosity O8 star as previously
suggested, but is either a high luminosity O8 star, or possibly an O8+WC binary
system.

</DOC>
<DOC>
<DOCNO> 118949 </DOCNO>
A radio-microlensing caustic crossing in B1600+434?


  First, we review the current status of the detection of strong `external'
variability in the CLASS gravitational B1600+434, focusing on the 1998 VLA
8.5-GHz and 1998/9 WSRT multi-frequency observations. We show that this data
can best be explained in terms of radio-microlensing. We then proceed to show
some preliminary results from our new multi-frequency VLA monitoring program,
in particular the detection of a strong feature (~30%) in the light curve of
the lensed image which passes predominantly through the dark-matter halo of the
lens galaxy. We tentatively interpret this event, which lasted for several
weeks, as a radio-microlensing caustic crossing, i.e. the superluminal motion
of a micro-arcsec-scale jet-component in the lensed source over a single
caustic in the magnification pattern, that has been created by massive compact
objects along the line-of-sight to the lensed image.

</DOC>
<DOC>
<DOCNO> 169835 </DOCNO>
Testing the Symmetrization Postulate on Molecules with Three Identical


  We propose an experiment to look for possible small violations of the
symmetrization postulate of Quantum Mechanics, in systems composed by three
identical particles. Such violations could be detected by investigating the
population of particular roto-vibrational states of symmetrical molecules
containing three identical nuclei. We discuss the symmetry properties of such
states, and the implications of the symmetrization postulate and of the
spin-statistics. A high sensitivity spectroscopic investigation on simple
molecules such as SO3, BH3 and NH3 could lead to the first test of the
symmetrization postulate for spin-0 and spin-1/2 nuclei.

</DOC>
<DOC>
<DOCNO> 122558 </DOCNO>
Relativistic Thermal Bremsstrahlung Gaunt Factor for the Intracluster


  We present accurate analytic fitting formulae for the frequency integrated
Gaunt factors for the relativistic as well as nonrelativistic thermal
bremsstrahlung which is relevant to the intracluster plasma. The fitting is
carried out for 1 =< Zj =< 28, 6.0 < log T < 8.5, where Zj is the charge number
of the ion, and T is the electron temperature in kelvins. The present analytic
fitting formulae will be useful for the analysis of the X-ray emission which
comes from the intracluster plasma as well as the other X-ray sources.

</DOC>
<DOC>
<DOCNO> 12235 </DOCNO>
Nothing moves a surface: vacancy mediated surface diffusion


  We report scanning tunneling microscopy observations, which imply that all
atoms in a close-packed copper surface move frequently, even at room
temperature. Using a low density of embedded indium `tracer' atoms, we
visualize the diffusive motion of surface atoms. Surprisingly, the indium atoms
seem to make concerted, long jumps. Responsible for this motion is an ultra-low
density of surface vacancies, diffusing rapidly within the surface. This
interpretation is supported by a detailed analysis of the displacement
distribution of the indium atoms, which reveals a shape characteristic for the
vacancy mediated diffusion mechanism that we propose.

</DOC>
<DOC>
<DOCNO> 68753 </DOCNO>
A D-brane alternative to unification


  We propose a minimal embedding of the Standard Model spectrum in a D-brane
configuration of type I string theory. The SU(3) color and SU(2) weak
interactions arise from two different collections of branes. The model is
neither grand unified nor supersymmetric but it naturally leads to the right
prediction of the weak angle for a string scale of the order of a few TeV. It
requires two Higgs doublets and guarantees proton stability.

</DOC>
<DOC>
<DOCNO> 68653 </DOCNO>
On the infrared behaviour of the (singlet) Higgs propagator


  We present a simple semi-perturbative argument in favour of a peculiar
infrared behaviour of the (singlet) Higgs propagator. On the basis of
`triviality' one expects a continuum limit with a two-point function
$\Gamma_2(q) \to (q^2 + M^2_h)$. However, this is not valid in the limit $q \to
0$ where one actually finds a singular behaviour. This is in agreement with
both non-perturbative analyses of the effective potential and with lattice
computations of the propagator and of the zero-momentum susceptibility in the
broken phase. The singular behaviour persists in an O(N) continuous-symmetry
theory, the case first pointed out by Symanzik, and supports the existence of
an extremely weak $1/r$ potential that does not disappear when coupling the
scalar fields to gauge bosons.

</DOC>
<DOC>
<DOCNO> 13776 </DOCNO>
Effect of Magnetic Impurities in Crystalline and Amorphous States of


  It has been observed that the effect of magnetic impurities in a
superconductor is drastically different depending on whether the host
superconductor is in a crystalline or an amorphous state. Based on the recent
theory of Kim and Overhauser, it is shown that as the system is getting
disordered, the initial slope of the $T_{c}$ depression is decreasing by a
factor $\sqrt{\ell/\xi_{0}}$, when the mean free path $\ell$ becomes smaller
than the BCS coherence length $\xi_{0}$, which is in agreement with
experimental findings. In addition, for a superconductor in a pure crystalline
state the superconducting transition temperature $T_{c}$ drops sharply from
about 50% of $T_{c0}$ (for a pure system) to zero near the critical impurity
concentration. This {\sl pure limit behavior} was indeed found by Roden and
Zimmermeyer in crystalline Cd.

</DOC>
<DOC>
<DOCNO> 10848 </DOCNO>
Novel coherent quantum bit using spatial quantization levels in


  As basic elements of the quantum computer - quantum bits (qubits) we offer
semiconductor quantum dots containing one electron each and consisting each of
two tunnel-connected parts. The numerical solution of a Schroedinger equation
with the account of Coulomb field of adjacent electrons shows, that in such
structures the realization of a full set of basic logic operations which are
necessary for fulfillment of quantum computations is possible. Durations of
one- and two-qubit operations versus qubit geometry are obtained. Decoherence
rates due to spontaneous emission of phonons and acoustic phonons (both
piezoelectric and deformation) are evaluated. Analysis of these rates shows the
offered qubit to be coherent enough to perform error correction procedures.

</DOC>
<DOC>
<DOCNO> 122800 </DOCNO>
Gamma-ray sources as relics of recent supernovae in the nearby Gould


  The nearby, 30 to 40 Myr old, starburst region of the Gould Belt has formed
numerous massive stars. Within its 300 pc radius, it produces core-collapse
supernovae at an enhanced rate which is shown to be 75 to 95 Myr{-1} kpc{-2},
i.e. 3 to 5 times higher than the local Galactic rate, over the past and future
few million years. A population of persistent, but unidentified, gamma-ray
sources has been recently singled out at medium latitudes above 100 MeV. Their
distribution across the sky is shown to be quite significantly and better
correlated with the tilted Gould Belt than with other Galactic structures. As
many as 40 +- 5 sources are statistically associated with the Belt at |b|> 5
deg. It is therefore proposed that these sources are part of the Belt and are
relics of the Belt supernovae in the form of million-year old pulsars. Their
presence stresses how active the local medium is, heated, enriched and shaped
by multiple recent explosions.

</DOC>
<DOC>
<DOCNO> 13241 </DOCNO>
Nonuniversal Correlations and Crossover Effects in the Bragg-Glass Phase


  The structural correlation functions of a weakly disordered Abrikosov lattice
are calculated in a functional RG-expansion in $d=4-\epsilon$ dimensions. It is
shown, that in the asymptotic limit the Abrikosov lattice exhibits still
quasi-long-range translational order described by a {\it nonuniversal} exponent
$\eta_{\bf G}$ which depends on the ratio of the renormalized elastic constants
$\kappa ={c}_{66}/ {c}_{11}$ of the flux line (FL) lattice. Our calculations
clearly demonstrate three distinct scaling regimes corresponding to the Larkin,
the random manifold and the asymptotic Bragg-glass regime. On a wide range of
{\it intermediate} length scales the FL displacement correlation function
increases as a power law with twice the manifold roughness exponent $\zeta_{\rm
RM}(\kappa) $, which is also {\it nonuniversal}. Correlation functions in the
asymptotic regime are calculated in their full anisotropic dependencies and
various order parameters are examined. Our results, in particular the
$\kappa$-dependency of the exponents, are in variance with those of the
variational treatment with replica symmetry breaking which allows in principle
an experimental discrimination between the two approaches.

</DOC>
<DOC>
<DOCNO> 120142 </DOCNO>
SN 1998bw at late phases


  We present observations of the peculiar supernova SN 1998bw, which was
probably associated with GRB 980425. The photometric and spectroscopic
evolution is monitored up to 500 days past explosion. We also present modeling
based on spherically symmetric, massive progenitor models and very energetic
explosions. The models allow line identification and clearly show the
importance of mixing. From the late light curves we estimate that about 0.3-0.9
solar masses of ejected Nickel-56 is required to power the supernova.

</DOC>
<DOC>
<DOCNO> 10269 </DOCNO>
Critical properties of projected SO(5) models at finite temperatures


  We consider the projected SO(5) bosonic model introduced in order to connect
the SO(5) theory of high-T$_c$ superconductivity with the physics of the
Mott-insulating gap, and derive the corresponding effective functional
describing low-energy degrees of freedom. At the
antiferromagnetic-superconducting transition, SO(5) symmetry-breaking effects
due to the gap are purely quantum mechanical and become irrelevant in the
neighborhood of a possible finite-temperature multicritical point separating
the normal from the antiferromagnetic and the superconducting phases. A
difference in the magnon and hole-pair mobility always takes the system away
from the SO(5)-symmetric fixed point towards a region of instability, and the
phase transition between the normal and the two ordered phases becomes first
order before merging into the antiferromagnetic-superconducting line. Quantum
fluctuations at intermediate temperatures, while introducing symmetry-breaking
terms in the case of equal mobilities, tend to cancel the symmetry-breaking
effects in the case of different mobilities.

</DOC>
<DOC>
<DOCNO> 150565 </DOCNO>
Harmonic Analysis and Superconformal Gauge Theories in Three Dimensions


  In this thesis I review various aspects of the AdS_4/CFT_3 correspondence,
where AdS_4 supergravity arises from compactification of M-theory on a coset
space G/H and preserves N<8 supersymmetries. One focal point of my review is
that the complete spectrum of such N-extended supergravity can be determined by
means of harmonic analysis on the homogeneous space G/H. This spectrum can be
matched with the candidate conformal theory on the boundary, in this way
providing very non-trivial checks of the AdS/CFT correspondence. Furthermore,
this spectrum can be useful to study the representation theory of N-extended
supersymmetry on AdS_4, namely representation theory for the superalgebra of
Osp(N|4). I review Osp(N|4) representation theory, and derive the translation
vocabulary between states of AdS_4 supergravity and conformal superfields on
the boundary, by means of the double interpretation of Osp(N|4) unitary
irreducible representations. In the cases of N=2,3, using results from harmonic
analysis I give the complete structure of all supermultiplets. Harmonic
analysis as a method to determine spectra of supergravity compactifications is
explained. Calculations are explicitly performed in the case
G/H=M^111=(SU(3)xSU(2)xU(1))/(SU(2)xU(1)xU(1)), preserving N=2 supersymmetries.
For this manifold, and also for the case G/H=Q^111=(SU(2)x
SU(2)xSU(2))/(U(1)xU(1)), I describe the construction of a candidate dual
superconformal theory on the boundary. This construction is based on
geometrical insight provided by the properties of the metric cone C(G/H)
transverse to the M2-brane worldvolume.

</DOC>
<DOC>
<DOCNO> 71147 </DOCNO>
Field Redefinitions at Finite Density


  The apparent dependence of nuclear matter observables on off-shell properties
of the two-nucleon potential is re-examined in the context of the effective
field theory (EFT) approach. Finite density (thermodynamic) observables are
invariant under field redefinitions, which extends the well-known theorem about
the invariance of S-matrix elements. Simple examples demonstrate how field
redefinitions can shift contributions between purely off-shell two-body
interactions and many-body forces, leaving both scattering and finite-density
observables unchanged. If only the transformed two-body potentials are kept,
however, the nuclear matter binding curves will depend on the off-shell part
(generating ``Coester bands''). The correspondence between field redefinitions
and unitary transformations, which have traditionally been used to generate
``phase-equivalent'' nucleon-nucleon potentials, is also demonstrated.

</DOC>
<DOC>
<DOCNO> 178987 </DOCNO>
Present Status of Realistic Shell-Model Calculations


  The present paper is comprised of two parts. First, we give a brief survey of
the theoretical framework for microscopic nuclear structure calculations
starting from a free nucleon-nucleon potential. Then, we present some selected
results of a comprehensive study of nuclei near doubly closed shells. In all
these shell-model calculations we have made use of realistic effective
interactions derived from the Bonn-A nucleon-nucleon potential by means of a
G-matrix folded-diagram method. We show that this kind of calculation yields a
very good agreement with experiment for all the nuclei considered. This leads
to the conclusion that realistic effective interactions are now able to
describe with quantitative accuracy the properties of complex nuclei.

</DOC>
<DOC>
<DOCNO> 68628 </DOCNO>
Q-ball collisions in the MSSM: gravity-mediated supersymmetry breaking


  Collisions of non-topological solitons, Q-balls, are studied in a typical
potential in the Minimal Supersymmetric Standard Model where supersymmetry has
been broken by a gravitationally coupled hidden sector. Q-ball collisions are
studied numerically on a two dimensional lattice for a range of Q-ball charges.
Total cross-sections, as well as cross-sections for fusion and charge-exchange
are calculated. The average percentage increase in charge carried by the
largest Q-ball after a collision is found to be weakly dependent on the initial
charge.

</DOC>
<DOC>
<DOCNO> 178554 </DOCNO>
The decay $\rho^{0}\to \pi^{+}+\pi^{-}+\gamma$ and the coupling constant


  The experimental branching ratio for the radiative decay
$\rho^{0}\to\pi^{+}+\pi^{-}+\gamma$ is used to estimate the coupling constant
$g_{\rho\sigma\gamma}$ for a set of values of $\sigma$-meson parameters
M$_{\sigma}$ and $\Gamma_{\sigma}$. Our results are quite different than the
values of this constant used in the literature.

</DOC>
<DOC>
<DOCNO> 102367 </DOCNO>
Kustin-Miller unprojection without complexes


  Gorenstein projections play a key role in birational geometry; the typical
example is the linear projection of a del Pezzo surface of degree d to one of
degree d-1, but variations on the same idea provide many of the classical and
modern birational links between Fano 3-folds. The inverse operation is the
Kustin-Miller unprojection theorem (A. Kustin and M. Miller, Constructing big
Gorenstein ideals from small ones, J. Algebra 85 (1983) 303--322), which
constructs "more complicated" Gorenstein rings starting from "less complicated"
ones (increasing the codimension by 1). We give a clean statement and proof of
their theorem, using the adjunction formula for the dualising sheaf in place of
their complexes and Buchsbaum-Eisenbud exactness criterion. Our methods are
scheme theoretic and work without any mention of the ambient space. They are
thus not restricted to the local situation, and are well adapted to
generalisations.

</DOC>
<DOC>
<DOCNO> 84863 </DOCNO>
A new solution for inflation


  Many pedagogical introductions of cosmological inflation are effective due to
the simplicity of the relevant equations. Here an analytic solution of the
cosmological equations is presented and used as an example to discuss
fundamental aspects of the inflationary paradigm.

</DOC>
<DOC>
<DOCNO> 122954 </DOCNO>
Constraining Isocurvature Perturbations with CMB Polarization


  The role of cosmic microwave background (CMB) polarisation data in
constraining the presence of primordial isocurvature modes is examined. While
the MAP satellite mission will be unable to simultaneously constrain
isocurvature modes and cosmological parameters, the PLANCK mission will be able
to set strong limits on the presence of isocurvature modes if it makes a
precise measurement of the CMB polarisation sky. We find that if we allow for
the possible presence of isocurvature modes, the recently obtained BOOMERANG
measurement of the curvature of the universe fails. However, a comparably
sensitive polarisation measurement on the same angular scales will permit a
determination of the curvature of the universe without the prior assumption of
adiabaticity.

</DOC>
<DOC>
<DOCNO> 84918 </DOCNO>
Dynamical Systems Approach to Magnetised Cosmological Perturbations


  Assuming a large-scale homogeneous magnetic field, we follow the covariant
and gauge-invariant approach used by Tsagas and Barrow to describe the
evolution of density and magnetic field inhomogeneities and curvature
perturbations in a matter-radiation universe. We use a two parameter
approximation scheme to linearize their exact non-linear general-relativistic
equations for magneto-hydrodynamic evolution. Using a two-fluid approach we set
up the governing equations as a fourth order autonomous dynamical system.
Analysis of the equilibrium points for the radiation dominated era lead to
solutions similar to the super-horizon modes found analytically by Tsagas and
Maartens. We find that a study of the dynamical system in the dust-dominated
era leads naturally to a magnetic critical length scale closely related to the
Jeans Length. Depending on the size of wavelengths relative to this scale,
these solutions show three distinct behaviours: large-scale stable growing
modes, intermediate decaying modes, and small-scale damped oscillatory
solutions.

</DOC>
<DOC>
<DOCNO> 122943 </DOCNO>
Cooling of Neutron Stars Revisited: Application of Low Energy Theorems


  Cooling of neutrons stars proceeds mainly via neutrino emission;
  As an example we study the modified neutrino bremsstrahlung process $nn \to
nn\nu\bar{\nu}.$
  The radiated energy is small compared to other scales in the system.
  Hence one can use low-energy theorems to compute the neutrino emissivity in
terms of the non-radiative process, ie the on-shell $T$ matrix. We find that
the use of the $T-$matrix as compared to previous estimates based upon one pion
exchange leads a substantial reduction of the predicted emissivity.

</DOC>
<DOC>
<DOCNO> 70394 </DOCNO>
Bimaximal Neutrino Mixing in a Zee-type Model with Badly Broken Flavor


  A Zee-type neutrino mass matrix model with a badly broken horizontal symmetry
SU(3)_H is investigated. By putting a simple ansatz on the symmetry breaking
effects of SU(3)_H for transition matrix elements, it is demonstrated that the
model can give a nearly bimaximal neutrino mixing with the ratio $\Delta
m^2_{solar}/\Delta m^2_{atm} \simeq \sqrt{2} m_e/m_{\mu}=6.7 \times 10^{-3}$,
which are in excellent agreement with the observed data. In the near future,
the lepton-number violating decay $Z\to \mu^\pm \tau^\mp$ will be observed.

</DOC>
<DOC>
<DOCNO> 152219 </DOCNO>
Topological Charge of U(1) Instantons


  Non-singular instantons are shown to exist on noncommutative R^4 even with a
U(1) gauge group. Their existence is primarily due to the noncommutativity of
the space. The relation between U(1) instantons on noncommutative R^4 and the
projection operators acting on the representation space of the noncommutative
coordinates is reviewed. The integer number of instantons on the noncommutative
R^4 can be understood as the winding number of the U(1) gauge field as well as
the dimension of the projection on the representation space.

</DOC>
<DOC>
<DOCNO> 12110 </DOCNO>
Phase shift effects on the second moment and skewness of the field


  Recent high transverse field muon spin relaxation (TF-uSR) experiments
performed on Bi2212 single crystals show that the phase parameter extracted
from individual histogram, an indication of the angle between the muon's
initial polarization direction and the detector direction, is temperature
dependent. This phase shift effect, probably due to the electronic or initial
polarization instability at a time interval comparable with the muon spin
precession period, will affect the second moment and skewness of the field
profiles. The proper data analysis procedure is discussed to correct this phase
shift effect, which is important on the quantitative interpretation of the
first order transition or melting transition in the Bi2212 mixed state.

</DOC>
<DOC>
<DOCNO> 116849 </DOCNO>
Funneling with the Two-Beam RFQ


  New high current accelerator facilities like proposed for HIDIF or ESS
require a beam with a high brilliance. These beams can not be produced by a
single pass rf-linac. The increase in brightness in such a driver linac is done
by several funneling stages at low energies, in which two identically bunched
ion beams are combined into a single beam with twice the frequency current and
brightness. Our Two-Beam-RFQ funneling experiment is a setup of two ion
sources, a two beam RFQ, a funnel deflector and beam diagnostic equipment to
demonstrate funneling of ion beams as a model for the first funneling stage of
a HIIF driver. The progress of the funneling experiment and results of
simulations will be presented.

</DOC>
<DOC>
<DOCNO> 151422 </DOCNO>
Supersymmetric Index In Four-Dimensional Gauge Theories


  This paper is devoted to a systematic discussion of the supersymmetric index
Tr (-1)^F for the minimal supersymmetric Yang-Mills theory -- with any simple
gauge group G -- primarily in four spacetime dimensions. The index has
refinements that probe confinement and oblique confinement and the possible
spontaneous breaking of chiral symmetry and of global symmetries, such as
charge conjugation, that are derived from outer automorphisms of the gauge
group. Predictions for the index and its refinements are obtained on the basis
of standard hypotheses about the infrared behavior of gauge theories. The
predictions are confirmed via microscopic calculations which involve a
Born-Oppenheimer computation of the spectrum as well as mathematical formulas
involving triples of commuting elements of G and the Chern-Simons invariants of
flat bundles on the three-torus.

</DOC>
<DOC>
<DOCNO> 68086 </DOCNO>
Virtual Sfermion Effects on Vector-Boson Pair Production at e^+e^-


  We study the quantum effects on vector-boson pair production in e^+e^-
annihilation induced by the sleptons and squarks of the minimal supersymmetric
extension of the standard model (MSSM) in the one-loop approximation. We list
full analytic results, and quantitatively analyze the resulting deviation from
the standard-model prediction of e^+e^- -> W^+W^- for the supergravity-inspired
MSSM. The latter can be rendered small throughout the whole parameter space by
an appropriate choice of renormalization scheme.

</DOC>
<DOC>
<DOCNO> 72211 </DOCNO>
Is there still a strong CP problem?


  A cloud of mystery surrounds the role of a chiral U(1) phase in the quark
mass in QCD. In operator formulation, parity is a symmetry and the phase is
easily removed by a mere change in the representation of the Dirac gamma
matrices. Moreover, these properties are also realized in a Pauli-Villars
regularized version of the theory. On the other hand, in the popular functional
integral scenario, attempts to remove the chiral phase by a chiral
transformation are frustrated by a nontrivial Jacobian arising from the fermion
measure and the chiral phase seems to have the potential to break parity. The
nontrivial Jacobian is shown to be the direct fallout of an unregularized
action, an essential ingredient in the popular scenario. The Jacobian becomes
trivial if one starts from the regularized action symmetric under parity in the
presence of the chiral phase, which can now be removed with impunity by chiral
rotation. The mystery melts away leading to a solution of the strong CP
problem.

</DOC>
<DOC>
<DOCNO> 121589 </DOCNO>
Discovery of An Extremely Metal--Poor Galaxy: Optical Spectroscopy of


  The results of optical spectroscopy of two HII regions in UGCA 292 (CVn I
dwA) are presented. UGCA 292 is a nearby (D=3.1 Mpc) gas-rich dwarf irregular
galaxy (M_H/L_B ~ 6.9) which was first discovered in a blind HI survey. The
derived oxygen abundance is the third lowest of known star-forming galaxies [12
+ log(O/H) = 7.30 +/- 0.05], making UGCA 292 one of the nearest metal-poor
galaxies known. The derived N/O ratio is similar to that found in other low
metallicity galaxies [log(N/O) = -1.47 +/- 0.10], and is indicative of a
primary origin for nitrogen. The derived oxygen abundance is consistent with
closed-box chemical evolution for this low mass galaxy. The observed blue
colors, high gas mass fraction, and low metallicity suggest that UGCA 292 is
relatively unevolved. The possibility that future blind HI surveys may yield
similar low metallicity galaxies is discussed.

</DOC>
<DOC>
<DOCNO> 117621 </DOCNO>
The infrared side of galaxy formation. I. The local universe in the


  We present a new evolutionary model for the far-UV to sub-mm properties of
the galaxy population. This combines a semi-analytic galaxy formation model
based on hierarchical clustering (GALFORM) with a spectro-photometric code
which includes dust reprocessing (GRASIL). The former provides the star
formation and metal enrichment histories, together with the gas mass and
various geometrical parameters, for a representative sample of galaxies formed
in different density environments. These quantities allow us to model the SEDs
of galaxies, taking into account stellar emission and also dust extinction and
re-emission. Two phases are considered for the dust: molecular cloud complexes,
where stars are assumed to be born, and the diffuse interstellar medium. The
model includes both galaxies forming stars quiescently in disks, and starbursts
triggered by galaxy mergers. We test our models against the observed
spectro-photometric properties of galaxies in the local Universe. The models
reproduce fairly well the SEDs of normal spirals and starbursts, and their
internal extinction properties. The starbursts follow the observed relationship
between the FIR to UV luminosity ratio and the slope of the UV continuum. They
also reproduce the observed starburst attenuation law (Calzetti et al 99). This
result is remarkable, because we use a dust mixture which reproduces the Milky
Way extinction law. It suggests that the observed attenuation law is related to
the geometry of the stars and dust. We compute galaxy luminosity functions over
our wide range of wavelengths, which turn out to be in good agreement with
observational data. The UV continuum turns out to be a poor star formation
indicator for our models, whilst the infrared luminosity is much more reliable.

</DOC>
<DOC>
<DOCNO> 117374 </DOCNO>
Near-infrared emission-line galaxies in the Hubble Deep Field North


  We present the 2.12~$\mu$m narrow-band image of the Hubble Deep Field North
taken with the near-infrared camera (CISCO) on the Subaru telescope. Among five
targets whose H$\alpha$ or [O~{\sc iii}] emission lines are redshifted into our
narrow-band range expected from their spectroscopic redshift, four of them have
strong emission lines, especially for the two [O~{\sc iii}] emission-line
objects. The remaining one target shows no H$\alpha$ emission in spite of its
bright rest-UV luminosity, indicating that this object is already under the
post-starburst phase. The volume-averaged $SFR$ derived from the detected two
H$\alpha$ emission is roughly consistent with that evaluated from the rest-UV
continuum.

</DOC>
<DOC>
<DOCNO> 69214 </DOCNO>
Weighing the universe with accelerators and detectors


  Suppose the lightest superpartner (LSP) is observed at colliders, and WIMPs
are detected in explicit experiments. We point out that one cannot immediately
conclude that cold dark matter (CDM) of the universe has been observed, and we
determine what measurements are necessary before such a conclusion is
meaningful. We discuss the analogous situation for neutrinos and axions; in the
axion case we have not found a way to conclude axions are the CDM even if
axions are detected.

</DOC>
<DOC>
<DOCNO> 99530 </DOCNO>
The Imbedding Sum of a Graph


  The automorphisms of a graph act naturally on its set of labeled imbeddings
to produce its unlabeled imbeddings. The imbedding sum of a graph is a
polynomial that contains useful information about a graph's labeled and
unlabeled imbeddings. In particular, the polynomial enumerates the number of
different ways the unlabeled imbeddings can be vertex colored and enumerates
the labeled and unlabeled imbeddings by their symmetries.

</DOC>
<DOC>
<DOCNO> 152299 </DOCNO>
Geometrization of the Quantum Effects


  A variant of the divergence theory for vacuum-structure developed previously
is analyzed from the viewpoint of a conformally invariant gravitational model.
Invariance breaking is introduced by choosing a preferred configuration of
dynamical variables. In this way a particle interpretation is presented which
leads to the geometrization of the quantum aspects of matter.

</DOC>
<DOC>
<DOCNO> 8345 </DOCNO>
Vortex Lattice Depinning vs. Vortex Lattice Melting: a pinning-based


  In this communication we argue that the Vortex Lattice Melting scenario fails
to explain several key experimental results published in the literature. From a
careful analysis of these results we conclude that the Flux Line Lattice (FLL)
does not melt along a material- and sample-dependent boundary $H_j(T)$ but the
opposite, it de-couples from the superconducting matrix becoming more ordered.
When the FLL depinning is sharp, the difference between the equilibrium
magnetization $M_{eq}(T,H)$ of the pinned and unpinned FLL leads to the
observed step-like change $\Delta M_{eq}(T,H)$. We demonstrate that the
experimentally obtained $\Delta M_{eq}(T,H)$ can be well accounted for by a
variation of the pinning efficiency of vortices along the $H_j(T)$ boundary.

</DOC>
<DOC>
<DOCNO> 83478 </DOCNO>
Automatic Termination Analysis of Programs Containing Arithmetic


  For logic programs with arithmetic predicates, showing termination is not
easy, since the usual order for the integers is not well-founded. A new method,
easily incorporated in the TermiLog system for automatic termination analysis,
is presented for showing termination in this case.
  The method consists of the following steps: First, a finite abstract domain
for representing the range of integers is deduced automatically. Based on this
abstraction, abstract interpretation is applied to the program. The result is a
finite number of atoms abstracting answers to queries which are used to extend
the technique of query-mapping pairs. For each query-mapping pair that is
potentially non-terminating, a bounded (integer-valued) termination function is
guessed. If traversing the pair decreases the value of the termination
function, then termination is established. Simple functions often suffice for
each query-mapping pair, and that gives our approach an edge over the classical
approach of using a single termination function for all loops, which must
inevitably be more complicated and harder to guess automatically. It is worth
noting that the termination of McCarthy's 91 function can be shown
automatically using our method.
  In summary, the proposed approach is based on combining a finite abstraction
of the integers with the technique of the query-mapping pairs, and is
essentially capable of dividing a termination proof into several cases, such
that a simple termination function suffices for each case. Consequently, the
whole process of proving termination can be done automatically in the framework
of TermiLog and similar systems.

</DOC>
<DOC>
<DOCNO> 71294 </DOCNO>
Charge Generation in the Oscillating Background


  The preheating after the inflation, which can be interpreted as particle
creation in the oscillating inflaton background, provides a state far from
thermal equilibrium. We extend the field theoretical treatment of the
preheating by Linde et al. to the case of multicomponent complex scalars to
show that some charges are created in this process, if C and CP are violated. A
new possibility of baryogenesis based on this mechanism is also discussed.

</DOC>
<DOC>
<DOCNO> 80786 </DOCNO>
Lattice QCD with the Overlap Fermions at Strong Gauge Coupling (II)


  In the previous paper we developed a strong-coupling expansion for the
lattice QCD with the overlap fermions and showed that L\"usher's "extended"
chiral symmetry is spontaneously broken in some parameter region of the overlap
fermions. In this paper, we derive a low-energy effective action of hadrons and
show that there exist quasi-Nambu-Goldstone bosons which are identified as the
pions. The pion field is a {\em nonlocal} composite field of quark and
anti-quark even at the strong-coupling limit because of the nonlocality of the
overlap fermion formalism and L\"usher's chiral symmetry. The pions become
massless in the limit of the vanishing bare-quark mass as it is desired. We
furthermore examine symmetries of the overlap fermions with the hopping
expansion and argue that there appear no other massless modes other than the
pions.

</DOC>
<DOC>
<DOCNO> 152141 </DOCNO>
The unifying superalgebra OSp(1|32)


  We show how OSp(1|32) gives a unifying framework to describe d=10 type II
string theories, d=11 M-theory and d=12 F-theory. The theories are related by
different identifications of their symmetry operators as generators of
OSp(1|32). T- and S-dualities are recognized as redefinitions of generators.
Some (s,t) signatures of spacetime allow reality conditions on the generators.
All those that allow a real structure are related again by redefinitions within
the algebra, due to the fact that the algebra OSp(1|32) has only one real
realization. The redefinitions include space/space, time/time and space/time
dualities. A further distinction between the theories is made by the
identification of the translation generator. This distinguishes various
versions of type II string theories, in particular the so-called *-theories,
characterized by the fact that the P_0 generator is not the (unique)
positive-definite energy operator in the algebra.

</DOC>
<DOC>
<DOCNO> 71804 </DOCNO>
Our wall as the origin of CP violation


  A possibility that the origin of the CP violation in our world is a domain
wall itself, on which we are living, is investigated in the context of the
brane world scenario. We estimate the amount of the CP violation on our wall,
and show that either of order one or suppressed CP phases can be realized. An
interesting case where CP is violated due to the {\it coexistence} of the
walls, which conserve CP individually, is also considered. We also propose a
useful approximation for the estimation of the CP violation in the double-wall
background.

</DOC>
<DOC>
<DOCNO> 11621 </DOCNO>
Determination of the orbit spaces of non-coregular compact linear groups


  Invariant functions under the transformations of a compact linear group $G$
acting in $\real^n$ can be expressed in terms of functions defined in the orbit
space of $G$. We develop a method to determine the isotropy classes of the
orbit spaces of all the real linear groups whose integrity bases (IB) satisfy
only one independent relation. The method is tested for IB's formed by 3
(independent) basic invariants. The result is obtained through a metric matrix
$\hat P(p)$, defined only from the scalar products between the gradients of a
minimal IB. We determine the matrices $\wP(p)$ from a universal differential
equation, which satisfy new convenient additional conditions, which fit for the
non-coregular case. Our results may be relevant in physical contexts where the
study of covariant or invariant functions is important, like in the
determination of patterns of spontaneous symmetry breaking in quantum field
theory, in the analysis of phase spaces and structural phase transitions
(Landau's theory), in covariant bifurcation theory, in crystal field theory and
so on.

</DOC>
<DOC>
<DOCNO> 40075 </DOCNO>
A triple GEM detector with two dimensional readout


  The triple GEM detector is a micropattern gas detector which consists of a
primary ionisation gap and three consecutive gas electron multiplier (GEM)
foils. A printed circuit board with readout strips detects the current induced
by the drifting electron cloud originating from the last GEM stage. Thus the
gas amplification and the signal readout are completely separated. Triple GEM
detectors are being developed as a possible technology for the inner tracking
in the LHCb experiment.
  In an earlier note we have reported first experience with such a detector in
a test beam at PSI. Here we describe the construction of an improved version
(thinner transfer gaps, segmented GEM foils, two dimensional readout). Results
from performance measurements are presented using intense hadronic beams as
well as cosmic ray data.

</DOC>
<DOC>
<DOCNO> 40055 </DOCNO>
New Evidence for Supernarrow Dibaryons Production in pd Interactions


  The analysis of new experimental data, obtained at the Proton Linear
Accelerator of INR, with the aim to search for supernarrow dibaryons in the
$pd\to ppX_1$ and $pd\to pdX_2$ reactions is presented. Narrow peaks with an
experimental width of 5 MeV at masses of 1904$\pm 2$, 1926$\pm 2$, and 1942$\pm
2$ MeV have been observed in missing mass $M_{pX_1}$ spectra. In the missing
mass $M_{X_1}$ spectra, the peaks at $M_{X_1}=966\pm 2$, 986$\pm 2$, and
1003$\pm 2$ MeV have been found. The analysis of the data obtained leads to the
conclusion that the observed peaks in $M_{pX_1}$ spectra are most likely
supernarrow dibaryons, the decay of which into two nucleons is forbidden by the
Pauli exclusion principle. An alternative interpretation of the spectra by
assuming a decay of the supernarrow dibaryons in "exotic baryon states" with
masses $M_{X_1}$ is discussed.

</DOC>
<DOC>
<DOCNO> 102387 </DOCNO>
SUSY Transformations for Quasinormal Modes of Open Systems


  Supersymmetry (SUSY) in quantum mechanics is extended from square-integrable
states to those satisfying the outgoing-wave boundary condition, in a
Klein-Gordon formulation. This boundary condition allows both the usual normal
modes and quasinormal modes with complex eigenvalues. The simple generalization
leads to three features: the counting of eigenstates under SUSY becomes more
systematic; the linear-space structure of outgoing waves (nontrivially
different from the usual Hilbert space of square-integrable states) is
preserved by SUSY; and multiple states at the same frequency (not allowed for
normal modes) are also preserved. The existence or otherwise of SUSY partners
is furthermore relevant to the question of inversion: are open systems uniquely
determined by their complex outgoing-wave spectra?

</DOC>
<DOC>
<DOCNO> 8792 </DOCNO>
Conductivity sum rule; comparison of coherent and incoherent c-axis


  We calculate the $c$-axis kinetic energy difference between normal and
superconducting state for coherent and for incoherent interlayer coupling
between CuO$_{2}$ planes. For coherent coupling the ratio of the missing
conductivity spectral weight to the superfluid density is equal to one and
there is no violation of the conventional sum rule, but for the incoherent case
we find it is always greater than one whatever the nature of the impurity
potential may be. To model more explicitly YBa$_{2}$Cu$_{3}$O$_{7-x}$ around
optimum doping, which is found to obey the sum rule, we consider a plane-chain
model and show that the sum rule still applies. A violation of the sum rule of
either sign is found even for coherent coupling when the in-plane density of
electronic states depends on energy on a scale of the order of the gap.

</DOC>
<DOC>
<DOCNO> 101181 </DOCNO>
Painlev\'e equations and deformations of rational surfaces with rational


  In this paper, we show that the B\"acklund transformations of Painlev\'e
equations come from birational maps of rational surfaces constructed by Okamoto
as the spaces of initial conditions.
 The simultaneous resolutions of rational double points of the families of
rational surfaces give rise to flops which are origins of symmetry groups of
Painlev\'e equation. Moreover we point out that Kodaira--Spencer theory of
deformations of rational surfaces explains a geomrtric meaning of Painlev\'e
equations.

</DOC>
<DOC>
<DOCNO> 14055 </DOCNO>
The calculation of parameters for Stevens Hamiltonian in a crystalline


  Exact expressions for the parameters of Stevens Hamiltonian are derived
within the framework of a specific model that assumes uniform character of
charge density distribution in a certain direction over crystalline lattice.
The new model is developed to strengthen the possibilities for analysis of
experimental data obtained by inelastic neutron scattering. It is particularly
valuable for studying the charge distribution in the layered perovskite-like
compounds doped with the rare-earth ions being used as a local probe.

</DOC>
<DOC>
<DOCNO> 119771 </DOCNO>
Gamma-Ray Emissions from Pulsars: Spectra of the TEV Fluxes from


  We study the gamma-ray emissions from an outer-magnetospheric potential gap
around a rotating neutron star. Migratory electrons and positrons are
accelerated by the electric field in the gap to radiate copious gamma-rays via
curvature process. Some of these gamma-rays materialize as pairs by colliding
with the X-rays in the gap, leading to a pair production cascade. Imposing the
closure condition that a single pair produces one pair in the gap on average,
we explicitly solve the strength of the acceleration field and demonstrate how
the peak energy and the luminosity of the curvature-radiated, GeV photons
depend on the strength of the surface blackbody and the power-law emissions.
Some predictions on the GeV emission from twelve rotation-powered pulsars are
presented. We further demonstrate that the expected pulsed TeV fluxes are
consistent with their observational upper limits. An implication of high-energy
pulse phase width versus pulsar age, spin, and magnetic moment is discussed.

</DOC>
<DOC>
<DOCNO> 85006 </DOCNO>
Possible direct method to determine the radius of a star from the


  We computed the spectrum of gravitational waves from a dust disk star of
radius R inspiraling into a Kerr black hole of mass M and specific angular
momentum a. We found that when R is much larger than the wave length of the
quasinormal mode, the spectrum has several peaks and the separation of peaks
$\Delta\omega$ is proportional to $R^{-1}$ irrespective of M and a. This
suggests that the radius of the star in coalescing binary black hole - star
systems may be determined directly from the observed spectrum of gravitational
wave. This also suggests that the spectrum of the radiation may give us
important information in gravitational wave astronomy as in optical astronomy.

</DOC>
<DOC>
<DOCNO> 68336 </DOCNO>
Parameter counting for neutrino mixing


  The content of physical massess, mixing angles and CP-violating phases in the
lepton sector of extended standard model, both renormalizable and
non-renormalizable, with arbitrary numbers of the singlet and left-handed
doublet neutrinos is systematically analyzed in the weak basis.

</DOC>
<DOC>
<DOCNO> 150406 </DOCNO>
Structure of Low-Energy Effective Action in N=4 Supersymmetric


  We study a problem of low-energy effective action in N=4 super Yang-Mills
theories. Using harmonic superspace approach we consider N=4 SYM in terms of
unconstrained N=2 superfield and apply N=2 background field method to finding
effective action for N=4 SU(n) SYM broken down to U(n)$^{n-1}$. General
structure of leading low-energy corrections to effective action is discussed
and calculational procedure for their explicit finding is presented.

</DOC>
<DOC>
<DOCNO> 170673 </DOCNO>
Slow-light pulses in moving media


  Slow light in moving media reaches a paradoxical regime when the flow speed
of the medium approaches the group velocity of light. Pulses can penetrate a
region where a counter-propagating flow exceeds the group velocity. When the
counter-flow slows down pulses are reflected.

</DOC>
<DOC>
<DOCNO> 10352 </DOCNO>
Physical Mechanism of the d->d+is Transition


  We discuss the basic physical mechanism of the d->d+is transition, which is
the currently accepted explanation for the results of tunneling experiments
into $ab$ planes. Using the first-order perturbation theory, we show that the
zero-bias states drive the transition. We present various order-of-magnitude
estimates and consistency checks that support this picture.

</DOC>
<DOC>
<DOCNO> 12590 </DOCNO>
Modelling sublimation and atomic layer epitaxy in the presence of


  We present a solid-on-solid model of a binary AB compound, where atoms of
type A in the topmost layer interact via anisotropic interactions different
from those inside the bulk. Depending on temperature and particle flux, this
model displays surface reconstructions similar to those of (001) surfaces of
II-VI semiconductors. We show, that our model qualitatively reproduces mamy of
the characteristic features of these materials which have been observed during
sublimation and atomic layer epitaxy. We predict some previously unknown
effects which might be observed experimentally.

</DOC>
<DOC>
<DOCNO> 70915 </DOCNO>
The Similarity Renormalization Group


  Quantum field theories require a cutoff to regulate divergences that result
from local interactions, and yet physical results can not depend on the value
of this cutoff. The renormalization group employs a transformation that changes
the cutoff to isolate hamiltonians that produce cutoff-independent eigenvalues.
The similarity renormalization group is based on similarity transformations
that regulate off-diagonal matrix elements, forcing the hamiltonian towards a
band-diagonal form as the cutoff is lowered. This avoids pathologies that
plagued tradition transformations acting on hamiltonians, making it possible to
produce a well-behaved perturbative approximation of renormalized hamiltonians
in asymptotically free theories. We employ a simple two-dimensional delta
function example to illustrate this new renormalization technique.

</DOC>
<DOC>
<DOCNO> 67938 </DOCNO>
Mediation of Supersymmetry Breaking via Anti-Generation Fields


  In the context of the weakly coupled heterotic string, we propose a new model
of mediating supersymmetry breaking. The breakdown of supersymmetry in the
hidden sector is transmitted to anti-generation fields via gravitational
interactions. Subsequent transmission of the breaking to the MSSM sector occurs
via gauge interactions. It is shown that the mass spectra of superparticles are
phenomenologically viable.

</DOC>
<DOC>
<DOCNO> 99795 </DOCNO>
Interpolation in ortholattices


  If L is a complete ortholattice, f any partial function from L^n to L, then
there is a complete ortholattice L* containing L as a subortholattice, and an
ortholattice polynomial with coefficients in L* which represents f on L^n.
  Iterating this construction long enough yields a complete ortholattice in
which every function can be interpolated by a polynomial on any set of small
enough cardinality.

</DOC>
<DOC>
<DOCNO> 11432 </DOCNO>
Permanent magnetic moment in mesoscopic metals with spin-orbit


  We argue that at zero temperature an isolated metal particle (or an AB ring)
with spin-orbit interaction and odd number of electrons will have a permanent
magnetic moment, even in zero magnetic field (flux). In a zero-field-cooled
state both the direction and the magnitude of the moment varies from particle
to particle and averages to zero. In a field-cooled state it averages to $\sim
\mu_{B}(k_{F}\ell) ^{1/2}$. We argue that the permanent moment is due to an
uncompensated electron in the last occupied (Fermi) level. We introduce an
effective single-electron Hamiltonian which accounts for spin-orbit coupling.

</DOC>
<DOC>
<DOCNO> 7890 </DOCNO>
A First Principles Study Of Cu Clusters


  In this communication we study the equilibrium shapes and energetics of Cu
clusters of various sizes upto 20 atoms using the Full-Potential Tight Binding
Muffin-tin Orbitals Molecular Dynamics. We compare our results with earlier
works by physicists and chemists using different methodologies.

</DOC>
<DOC>
<DOCNO> 69206 </DOCNO>
Parity-violating electromagnetic interactions in QED_3 at finite


  We study the parity-breaking terms generated by the box diagram in 2+1
dimensional thermal QED. These lead, in the long wave limit, to a gauge
invariant extensive action which behaves as 1/T at high temperature. In
contrast, the effective action in the static limit involves leading
non-extensive terms proportional to 1/T^3 at high temperature, which violate
large gauge invariance. We derive a non-linear large gauge Ward identity, which
relates the leading static terms of different order in perturbation theory and
whose solution coincides with the all order effective action proposed earlier.

</DOC>
<DOC>
<DOCNO> 8960 </DOCNO>
Mean field and Monte Carlo studies of the magnetization-reversal


  Detailed mean field and Monte Carlo studies of the dynamic
magnetization-reversal transition in the Ising model in its ordered phase under
a competing external magnetic field of finite duration have been presented
here. Approximate analytical treatment of the mean field equations of motion
shows the existence of diverging length and time scales across this dynamic
transition phase boundary. These are also supported by numerical solutions of
the complete mean field equations of motion and the Monte Carlo study of the
system evolving under Glauber dynamics in both two and three dimensions.
Classical nucleation theory predicts different mechanisms of domain growth in
two regimes marked by the strength of the external field, and the nature of the
Monte Carlo phase boundary can be comprehended satisfactorily using the theory.
The order of the transition changes from a continuous to a discontinuous one as
one crosses over from coalescence regime (stronger field) to nucleation regime
(weaker field). Finite size scaling theory can be applied in the coalescence
regime, where the best fit estimates of the critical exponents are obtained for
two and three dimensions.

</DOC>
<DOC>
<DOCNO> 70664 </DOCNO>
Dileptons from $\eta_c$ in Nucleus-Nucleus collisions


  Preliminary estimates suggest that excess dimuon production with invariant
mass in the range 1.5 -- 2.5 GeV in nucleus-nucleus collisions can be explained
on the basis of $\eta_c$ production. This appears to be consistent with all the
peripheral and central collision data with various nuclei such as S-U at 200
GeV/nucleon except for the central collision data on Pb-Pb at 158 GeV/nucleon.
Some explanations based on glueball production for Pb-Pb data are discussed.

</DOC>
<DOC>
<DOCNO> 102237 </DOCNO>
Murnaghan-Nakayama Rules for the Characters of the Wenzl


  This paper has been withdrawn by the author because he was informed of the
following paper:
  Cummins C. and King R. C., An algorithm for calculating characters of Hecke
algebras Hn (q) of tyoe An-1 when q is a root of unity, Comm. Algebra 21
(1993), no.12 4425-4437 by its first author. The author's main result seems to
be included in their result.

</DOC>
<DOC>
<DOCNO> 152050 </DOCNO>
Structural aspects of the fermion-boson mapping in two-dimensional gauge


  Using a synthesis of the functional integral and operator approaches we
discuss the fermion-boson mapping and the role played by the Bose field algebra
in the Hilbert space of two-dimensional gauge and anomalous gauge field
theories with massive fermions. In the $QED_2$ with quartic self-interaction
among massive fermions, the use of an auxiliary vector field introduces a
redundant Bose field algebra that should not be considered as an element of the
intrinsic algebraic structure defining the model. In the anomalous chiral
$QED_2$ with massive fermions the effect of the chiral anomaly leads to the
appearance in the mass operator of a spurious Bose field combination. This
phase factor carries no fermion selection rule and the expected absence of
$\theta$-vacuum in the anomalous model is displayed from the operator solution.
Even in the anomalous model with massive Fermi fields, the introduction of the
Wess-Zumino field replicates the theory, changing neither its algebraic content
nor its physical content.

</DOC>
<DOC>
<DOCNO> 170688 </DOCNO>
Separable states are more disordered globally than locally


  A remarkable feature of quantum entanglement is that an entangled state of
two parties, Alice (A) and Bob (B), may be more disordered locally than
globally. That is, S(A) > S(A,B), where S(.) is the von Neumann entropy. It is
known that satisfaction of this inequality implies that a state is
non-separable. In this paper we prove the stronger result that for separable
states the vector of eigenvalues of the density matrix of system AB is
majorized by the vector of eigenvalues of the density matrix of system A alone.
This gives a strong sense in which a separable state is more disordered
globally than locally and a new necessary condition for separability of
bipartite states in arbitrary dimensions. We also investigate the extent to
which these conditions are sufficient to characterize separability, exhibiting
examples that show separability cannot be characterized solely in terms of the
local and global spectra of a state. We apply our conditions to give a simple
proof that non-separable states exist sufficiently close to the completely
mixed state of $n$ qudits.

</DOC>
<DOC>
<DOCNO> 9726 </DOCNO>
Trajectory versus probability density entropy


  We study the problem of entropy increase of the Bernoulli-shift map without
recourse to the concept of trajectory and we discuss whether, and under which
conditions if it does, the distribution density entropy coincides with the
Kolmogorov-Sinai entropy, namely, with the trajectory entropy.

</DOC>
<DOC>
<DOCNO> 8504 </DOCNO>
Foundations of Dissipative Particle Dynamics


  We derive a mesoscopic modeling and simulation technique that is very close
to the technique known as dissipative particle dynamics. The model is derived
from molecular dynamics by means of a systematic coarse-graining procedure.
Thus the rules governing our new form of dissipative particle dynamics reflect
the underlying molecular dynamics; in particular all the underlying
conservation laws carry over from the microscopic to the mesoscopic
descriptions. Whereas previously the dissipative particles were spheres of
fixed size and mass, now they are defined as cells on a Voronoi lattice with
variable masses and sizes. This Voronoi lattice arises naturally from the
coarse-graining procedure which may be applied iteratively and thus represents
a form of renormalisation-group mapping. It enables us to select any desired
local scale for the mesoscopic description of a given problem. Indeed, the
method may be used to deal with situations in which several different length
scales are simultaneously present. Simulations carried out with the present
scheme show good agreement with theoretical predictions for the equilibrium
behavior.

</DOC>
<DOC>
<DOCNO> 100185 </DOCNO>
J-holomorphic Curves, Bubbling and Reeb Closed Orbits


  We prove that there exists at least one closed Reeb orbit for a closed
contact manifold with any contact form which gives a complete solution on the
Weinstein conjecture as a corollary.

</DOC>
<DOC>
<DOCNO> 120671 </DOCNO>
Gravitational Time Delay Effects on CMB Anisotropies


  We study the effect of gravitational time delay on the power spectra and
bispectra of the cosmic microwave background (CMB) temperature and polarization
anisotropies. The time delay effect modulates the spatial surface at
recombination on which temperature anisotropies are observed, typically by ~1
Mpc. While this is a relatively large shift, its observable effects in the
temperature and polarization fields are suppressed by geometric considerations.
The leading order effect is from its correlation with the closely related
gravitational lensing effect. The change to the temperature-polarization cross
power spectrum is of order 0.1% and is hence comparable to the cosmic variance
for the power in the multipoles around l~1000. While unlikely to be extracted
from the data in its own right, its omission in modeling would produce a
systematic error comparable to this limiting statistical error and, in
principle, is relevant for future high precision experiments. Contributions to
the bispectra result mainly from correlations with the Sachs-Wolfe effect and
may safely be neglected in a low density universe.

</DOC>
<DOC>
<DOCNO> 10607 </DOCNO>
Derivation of the probability distribution function for the local


  We consider the statistical properties of the local density of states of a
one-dimensional Dirac equation in the presence of various types of disorder
with Gaussian white-noise distribution. It is shown how either the replica
trick or supersymmetry can be used to calculate exactly all the moments of the
local density of states. Careful attention is paid to how the results change if
the local density of states is averaged over atomic length scales. For both the
replica trick and supersymmetry the problem is reduced to finding the ground
state of a zero-dimensional Hamiltonian which is written solely in terms of a
pair of coupled ``spins'' which are elements of u(1,1). This ground state is
explicitly found for the particular case of the Dirac equation corresponding to
an infinite metallic quantum wire with a single conduction channel. The
calculated moments of the local density of states agree with those found
previously by Al'tshuler and Prigodin [Sov. Phys. JETP 68 (1989) 198] using a
technique based on recursion relations for Feynman diagrams.

</DOC>
<DOC>
<DOCNO> 118764 </DOCNO>
Radio Detection of High Energy Particles: Coherence Versus Multiple


  Radio Cherenkov emission underlines detection of high energy particles via a
signal growing like the particle-energy-squared. Cosmic ray-induced
electromagnetic showers are a primary application. While many studies have
treated the phenomenon approximately, none have attempted to incorporate all
the physical scales involved in problems with time- or spatially- evolving
charges. We find it is possible to decompose the calculated fields into the
product of a form factor, characterizing a moving charge distribution,
multiplying a general integral which depends on the charge evolution. In
circumstances of interest for cosmic ray physics, the resulting expressions can
be evaluated explicitely in terms of a few parameters obtainable from shower
codes. The classic issues of Frauhofer and Fresnel zones play a crucial role in
the coherence.

</DOC>
<DOC>
<DOCNO> 150856 </DOCNO>
Two-loop beta functions of the Sine-Gordon model


  We recalculate the two-loop beta functions in the two-dimensional Sine-Gordon
model in a two-parameter expansion around the asymptotically free point. Our
results agree with those of Amit et al., J. Phys. A13 (1980) 585.

</DOC>
<DOC>
<DOCNO> 116594 </DOCNO>
Irradiation of benzene molecules by ion-induced and light-induced


  Benzene, with its sea of delocalized $\pi$-electrons in the valence orbitals,
is identified as an example of a class of molecules that enable establishment
of the correspondence between intense ion-induced and laser-light-induced
fields in experiments that probe ionization dynamics in temporal regimes
spanning the attosecond and picosecond ranges.

</DOC>
<DOC>
<DOCNO> 12120 </DOCNO>
Effects of confinement and surface enhancement on superconductivity


  Within the Ginzburg-Landau approach a theoretical study is performed of the
effects of confinement on the transition to superconductivity for type-I and
type-II materials with surface enhancement. The superconducting order parameter
is characterized by a negative surface extrapolation length $b$. This leads to
an increase of the critical field $H_{c3}$ and to a surface critical
temperature in zero field, $T_{cs}$, which exceeds the bulk $T_c$. When the
sample is {\em mesoscopic} of linear size $L$ the surface induces
superconductivity in the interior for $T < T_{c}(L)$, with $T_c(L) > T_{cs}$.
In analogy with adsorbed fluids, superconductivity in thin films of type-I
materials is akin to {\em capillary condensation} and competes with the
interface delocalization or "wetting" transition. The finite-size scaling
properties of capillary condensation in superconductors are scrutinized in the
limit that the ratio of magnetic penetration depth to superconducting coherence
length, $\kappa \equiv \lambda/\xi $, goes to zero, using analytic
calculations. While standard finite-size scaling holds for the transition in
non-zero magnetic field $H$, an anomalous critical-point shift is found for
H=0. The increase of $T_c$ for H=0 is calculated for mesoscopic films,
cylindrical wires, and spherical grains of type-I and type-II materials.
Surface curvature is shown to induce a significant increase of $T_c$,
characterized by a shift $T_c(R)-T_c(\infty)$ inversely proportional to the
radius $R$.

</DOC>
<DOC>
<DOCNO> 83333 </DOCNO>
Structure of some sand pile model


  SPM (Sand Pile Model) is a simple discrete dynamical system used in physics
to represent granular objects. It is deeply related to integer partitions, and
many other combinatorics problems, such as tilings or rewriting systems. The
evolution of the system started with n stacked grains generates a lattice,
denoted by SPM(n). We study here the structure of this lattice. We first
explain how it can be constructed, by showing its strong self-similarity
property. Then, we define SPM(infini), a natural extension of SPM when one
starts with an infinite number of grains. Again, we give an efficient
construction algorithm and a coding of this lattice using a self-similar tree.
The two approaches give different recursive formulae for the cardinal of
SPM(n), where no closed formula have ever been found.

</DOC>
<DOC>
<DOCNO> 8536 </DOCNO>
Various regimes of flux motion in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$


  Four regimes of vortex motion were identified in the magnetoresistance of
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ single crystals: (1) thermally activated
flux flow (TAFF) in samples with surface defects caused by thermal annealing;
(2) TAFF-like plastic motion of highly entangled vortex liquid at low
temperatures, with $U_{pl} \sim (1-T/T_c)/H^{1/2}$; (3) pure free flux flow
above the region of (2) in clean and optimally doped samples; or, in its place,
(4) a combination of (2) and (3). This analysis gives an overall picture of
flux motion in Bi cuprates.

</DOC>
<DOC>
<DOCNO> 117736 </DOCNO>
Early Galactic Evolution of Carbon, Nitrogen and Oxygen


  We present results on carbon, nitrogen, and oxygen abundances for a sample of
unevolved metal-poor stars with metallicities in the range -0.3< [Fe/H]< -3.
Oxygen abundances derived from different indicators are compared showing
consistently that in the range 0.3 >[Fe/H]>-3.0, the [O/Fe] ratio increases
from approximately 0 to 1. We find a good agreement between abundances based on
the forbidden line, the OH and IR triplet lines when gravities based on
Hipparcos} parallaxes are considered for the sample stars. Gravities derived
from LTE ionization balance in metal-poor stars with [Fe/H]< -1 are likely too
low, and could be responsible for an underestimation of the oxygen abundances
derived using the [OI] line. [C/Fe] and [N/Fe] ratios appear to be constant,
independently of metallicity, in the same range. However, they show larger
scatter than oxygen at a given metallicity, which could reflect the larger
variety of stellar production sites for these other elements.

</DOC>
<DOC>
<DOCNO> 118795 </DOCNO>
A Comparative Study of the Depth of Maximum of Simulated Air Shower


  A comparative study of simulated air shower longitudinal profiles is
presented. An appropriate thinning level for the calculations is first
determined empirically. High statistics results are then provided, over a wide
energy range, (10^14.0 to 10^20.5 eV), for proton & iron primaries, using four
combinations of the MOCCA & CORSIKA program frameworks, and the SIBYLL & QGSJET
high energy hadronic interaction models. These results are compared to existing
experimental data. The way in which the first interaction controls Xmax is
investigated, as is the distribution of Xmax.

</DOC>
<DOC>
<DOCNO> 117919 </DOCNO>
Self-regulated hydrodynamical process in halo stars : a possible


  It has been known for a long time (Mestel~1953) that the meridional
circulation velocity in stars, in the presence of mu-gradients, is the sum of
two terms, one due to the classical thermal imbalance (Omega-currents) and the
other one due to the induced horizontal mu-gradients (mu-induced currents, or
mu-currents in short). In the most general cases, mu-currents are opposite to
Omega-currents. Vauclair (1999) has shown that such processes can, in specific
cases, lead to a quasi-equilibrium stage in which both the circulation and the
helium settling is frozen. Here we present computations of the circulation
currents in halo star models, along the whole evolutionary sequences for four
stellar masses with a metallicity of [Fe/H] = -2. We show that such a
self-regulated process can account for the constancy of the lithium abundances
and the small dispersion in the Spite plateau.

</DOC>
<DOC>
<DOCNO> 10982 </DOCNO>
Inhomogeneous broadening of tunneling conductance in double quantum


  The lineshape of the tunneling conductance in double quantum wells with a
large-scale roughness of heterointerfaces is investigated. Large-scale
variations of coupled energy levels and scattering due to the short-range
potential are taken into account. The interplay between the inhomogeneous
broadening, induced by the non-screened part of large-scale potential, and the
homogeneous broadening due to the scattering by short-range potentials is
considered. It is shown that the large inhomogeneous broadening can be strongly
modified by nonlocal effects involved in the proposed mechanism of
inhomogeneity. Related change of lineshape of the resonant tunneling
conductance between Gaussian and Lorentzian peaks is described. The theoretical
results agree quite well with experimental data.

</DOC>
<DOC>
<DOCNO> 100567 </DOCNO>
A Proof of "Goldbach's Conjecture"


  "Goldbach's Conjecture" proven by analysis of how all combinations of the odd
primes, summed in pairs, generates all of the even numbers.

</DOC>
<DOC>
<DOCNO> 13192 </DOCNO>
Conformations of amphiphilic diblock star copolymers


  We study conformations assumed by single diblock star copolymers in a poor
solvent by means of the Gaussian variational theory and Monte Carlo simulation
in continuous space. Cases of stars with internal and external hydrophobic
blocks are analysed. While in the former case the collapsed state has an
obvious micellar shape, the latter case exhibits two nontrivial conformational
structures. Apart from the equilibrium state of a globular hydrophobic core
with hydrophilic daisy loops, one also finds here a metastable state of
outstretched hydrophilic blocks with hydrophobic subglobules at their ends.
Such a state appears to be rather long-lived during the kinetics of collapse of
a swollen star. The plots of monomer densities and other observables computed
by both techniques are found to be in good agreement with each other.

</DOC>
<DOC>
<DOCNO> 13468 </DOCNO>
Critical thermodynamics of three-dimensional MN-component field model


  The critical behavior of an MN-component order parameter Ginzburg-Landau
model with isotropic and cubic interactions describing antiferromagnetic and
structural phase transitions in certain crystals with complicated ordering is
studied in the framework of the four-loop renormalization group (RG) approach
in $(4-2\ve)$-dimensions. Using dimensional regularization and the minimal
subtraction scheme, the perturbative expansions for RG functions are deduced
for generic M and N and resummed by the Borel transformation combined with a
conformal mapping. Investigation of the global structure of RG flows for the
physically significant cases M=2 and N=2, N=3 shows that the model has a
three-dimensionally stable fixed point different from the Bose one. The
critical dimensionality is proved to be exactly two times smaller than its
counterpart in the real cubic model: N_c^C ={1/2} N_c^R. The numerical value
$N_c^C=1.447 \pm 0.020$ is obtained from resumming the known five-loop
$\ve$-series for N_c^R. Since N_c^C < 2, the critical thermodynamics of the
model relevant to the phase transitions in real substances should be governed
by the complex cubic fixed point with a new set of critical exponents:
$\gm=1.404(25)$, $\nu=0.715(10)$, $\et=0.0343(20)$ for N=2 and $\gm=1.390(25)$,
$\nu=0.702(10)$, $\et=0.0345(15)$ for N=3.

</DOC>
<DOC>
<DOCNO> 70649 </DOCNO>
The light Higgs window in the 2HDM at GigaZ


  The sensitivity to a light Higgs boson in the general 2HDM (II), with a mass
below 40 GeV, is estimated for an future e+e- linear collider operating with
very high luminosity at the Z peak (GigaZ). We consider a possible Higgs boson
production via the Bjorken process, the (hA) pair production, the Yukawa
process Z -> b {\bar b} h(A), -> tau {\bar tau} h(A), and the decay Z
->h(A)+gamma. Although the discovery potential is considerably extended
compared to the current sensitivities, mainly from LEP, the existence of a h or
A even with a mass of a few GeV cannot be excluded with two billion Z decays.
The need to study the very light Higgs scenario at a linear e+e- collider
running at several hundred GeV and the LHC is emphasised.

</DOC>
<DOC>
<DOCNO> 70368 </DOCNO>
Why Use a Hamilton Approach in QCD?


  We discuss $QCD$ in the Hamiltonian frame work. We treat finite density $QCD$
in the strong coupling regime. We present a parton-model inspired
regularisation scheme to treat the spectrum ($\theta$-angles) and distribution
functions in $QED_{1+1}$. We suggest a Monte Carlo method to construct
low-dimensionasl effective Hamiltonians. Finally, we discuss improvement in
Hamiltonian $QCD$.

</DOC>
<DOC>
<DOCNO> 119680 </DOCNO>
Line formation in solar granulation: II. The photospheric Fe abundance


  The solar photospheric Fe abundance has been determined using realistic ab
initio 3D, time-dependent, hydrodynamical model atmospheres. The study is based
on the excellent agreement between the predicted and observed line profiles
directly rather than equivalent width, since the intrinsic Doppler broadening
from the convective motions and oscillations provide the necessary non-thermal
broadening. Thus, three of the four hotly debated parameters (equivalent
widths, microturbulence and damping enhancement factors) in the center of the
recent solar Fe abundance dispute regarding FeI lines no longer enter the
analysis, leaving the transition probabilities as the main uncertainty. Both
FeI (using the samples of lines of both the Oxford and Kiel studies) and FeII
lines have been investigated, which give consistent results: log FeI = 7.44 +-
0.05 and log FeII = 7.45 +- 0.10. Also the wings of strong FeI lines return
consistent abundances, log FeII = 7.42 +- 0.03, but due to the uncertainties
inherent in analyses of strong lines we give this determination lower weight
than the results from weak and intermediate strong lines. In view of the recent
slight downward revision of the meteoritic Fe abundance log Fe = 7.46 +- 0.01,
the agreement between the meteoritic and photospheric values is very good, thus
appearingly settling the debate over the photospheric Fe abundance from FeI
lines.

</DOC>
<DOC>
<DOCNO> 101052 </DOCNO>
Almost Hermitian Geometry on Six Dimensional Nilmanifolds


  The fundamental 2-form of an invariant almost Hermitian structure on a
6-dimensional Lie group is described in terms of an action by SO(4)xU(1) on
complex projective 3-space. This leads to a combinatorial description of the
classes of almost Hermitian structures on the Iwasawa and other nilmanifolds.

</DOC>
<DOC>
<DOCNO> 84332 </DOCNO>
A new cosmological tracker solution for Quintessence


  In this paper we propose a quintessence model with the potential $V(\Phi
)=V_{o}[ \sinh {(\alpha \sqrt{\kappa_{o}}\Delta \Phi})] ^{\beta}$, which
asymptotic behavior corresponds to an inverse power-law potential at early
times and to an exponential one at late times. We demonstrate that this is a
tracker solution and that it could have driven the Universe into its current
inflationary stage. The exact solutions and the description for a complete
evolution of the Universe are also given. We compare such model with the
current cosmological observations.

</DOC>
<DOC>
<DOCNO> 151034 </DOCNO>
An N=2 gauge theory and its supergravity dual


  We study flows on the scalar manifold of N=8 gauged supergravity in five
dimensions which are dual to certain mass deformations of N=4 super Yang--Mills
theory. In particular, we consider a perturbation of the gauge theory by a mass
term for the adjoint hyper-multiplet, giving rise to an N=2 theory. The exact
solution of the 5-dim gauged supergravity equations of motion is found and the
metric is uplifted to a ten-dimensional background of type-IIB supergravity.
Using these geometric data and the AdS/CFT correspondence we analyze the
spectra of certain operators as well as Wilson loops on the dual gauge theory
side. The physical flows are parametrized by a single non-positive constant and
describe part of the Coulomb branch of the N=2 theory at strong coupling. We
also propose a general criterion to distinguish between `physical' and
`unphysical' curvature singularities. Applying it in many backgrounds arising
within the AdS/CFT correspondence we find results that are in complete
agreement with field theory expectations.

</DOC>
<DOC>
<DOCNO> 11421 </DOCNO>
Field-Theoretic Approach to Ionic Systems: Criticality and


  A Landau-Ginzburg functional of two order parameters (charge-density $\phi$
and mass-density deviation $\eta$) is developed in order to yield a field
theory relevant to ionic lattice gases as well as a family of off-lattice
models of ionic fluids that go beyond the restricted primitive model (RPM). In
a mean-field (MF) approximation an instability of a uniform phase with respect
to charge fluctuations with a wave-number $k\ne 0$ is found. This second-order
transition to a charge-ordered phase terminates at a tricritical point (tcp).
Beyond MF, a singularity of a mass correlation function for $k\to 0$ occurs at
ion concentration lower than that of the MF tcp. An effective functional
depending only on $\eta$ is constructed. For low ion concentration the usual
Landau form of the simple-fluid (Ising) functional is obtained; hence in this
theory the critical point is in the Ising universality class.

</DOC>
<DOC>
<DOCNO> 151932 </DOCNO>
Selfdual backgrounds in N=2 five-dimensional Chern-Simons Supergravity


  We consider five-dimensional S(2,2|N) Chern-Simons supergravity on M_4 * R .
By fine-tuning the Kaluza-Klein reduction to make the 4d cosmological constant
equal zero, it is shown that selfdual curvatures on M_4 provide exact solutions
to the equations of motion if N=2.

</DOC>
<DOC>
<DOCNO> 84265 </DOCNO>
Compact stellar objects with multiple neck optical geometries


  Ultra compact stellar models with a two-zone uniform density equation of
state are considered. They are shown to provide neat examples of optical
geometries exhibiting double necks, implying that the gravitational wave
potential has a double well structure.

</DOC>
<DOC>
<DOCNO> 121802 </DOCNO>
Spatial Distributions of Multiple Dust Components in the PPN/PN Dust


  We investigate spatial distributions of specific dust components in the
circumstellar shells of a proto-planetary nebula candidate, HD 179821, and a
planetary nebula, BD$+30^{\circ}$3639, by means of spectral imaging. With
high-resolution ground-based images and ISO spectra in the mid-infrared, we can
derive ``dust feature only'' maps by subtracting synthesized continuum maps
from the observed images at the feature wavelength. Such spatially detailed
information will help to develop models for the evolution of dust grains around
evolved stars.

</DOC>
<DOC>
<DOCNO> 102454 </DOCNO>
A note on the precompactness of weakly almost periodic groups


  An action of a group $G$ on a compact space $X$ is called weakly almost
periodic if the orbit of every continuous function on $X$ is weakly relatively
compact in $C(X)$. We observe that for a topological group $G$ the following
are equivalent: (i) every continuous action of $G$ on a compact space is weakly
almost periodic; (ii) $G$ is precompact. For monothetic groups the result was
previously obtained by Akin and Glasner, while for locally compact groups it
has been known for a long time.

</DOC>
<DOC>
<DOCNO> 69667 </DOCNO>
Decay and Decoupling of heavy Right-handed Majorana Neutrinos in the L-R


  Heavy right-handed neutrinos are of current interest. The interactions and
decay of such neutrinos determine their decoupling epoch during the evolution
of the universe. This in turn affects various observable features like the
energy density, nucleosynthesis, CMBR spectrum, galaxy formation, and
baryogenesis. Here, we consider reduction of right-handed electron-type
Majorana neutrinos, in the left-right symmetric model, by the WR+ - WR- channel
and the channel originating from an anomaly, involving the SU(2)R gauge group,
as well as decay of such neutrinos. We study the reduction of these neutrinos
for different ranges of left-right model parameters, and find that, if the
neutrino mass exceeds the right-handed gauge boson mass, then the neutrinos
never decouple for realistic values of the parameters, but, rather, decay in
equilibrium. Because there is no out-of-equilibrium decay, no mass bounds can
be set for the neutrinos.

</DOC>
<DOC>
<DOCNO> 120375 </DOCNO>
The Cosmological Mass Function in the Zel'dovich Approximation


  The Press-Schechter theory of the cosmological mass function and its
modifications allow to constraint cosmological scenarios of the structure
formation. Recently a few new models have been suggested that explored the
influence of anisotropic collapse on the shape of the mass function. I discuss
in more detail a particular model that assumes that a fluid particle becomes a
part of a gravitationally bound halo when the smallest eigenvalue of the
deformation tensor of the filtered initial density field reaches a certain
threshold (like the filtered density contrast reaches the threshold in the
Press-Schechter formalism). Choosing the smallest eigenvalue guarantees that
the fluid particle in question experiences collapse along all three axes. The
model shows a better agreement with the N-body simulations than the standard
Press-Schechter model.

</DOC>
<DOC>
<DOCNO> 84919 </DOCNO>
Resolving the black hole information paradox


  The recent progress in string theory strongly suggests that formation and
evaporation of black holes is a unitary process. This fact makes it imperative
that we find a flaw in the semiclassical reasoning that implies a loss of
information. We propose a new criterion that limits the domain of classical
gravity: the hypersurfaces of a foliation cannot be stretched too much. This
conjectured criterion may have important consequences for the early Universe.

</DOC>
<DOC>
<DOCNO> 119798 </DOCNO>
Reconstructing PSCz with a Generalised PIZA


  We present a generalized version of the Path Interchange Zel'dovich
Approximation (PIZA), for use with realistic galaxy redshift surveys. PIZA is a
linear particle-based Lagrangian method which uses the present day positions of
galaxies to reconstruct both the initial density field and the present day
peculiar velocity field. We generalize the method by mapping galaxy positions
from redshift-space to real-space in the Local Group frame, and take the
selection function into account by minimizing the mass weighted action. We have
applied our new method to mock galaxy catalogues, and find it offers an
improvement in the accuracy of reconstructions over linear theory. We have
applied our method to the all-sky IRAS Point Source Catalogue Redshift Survey.
Applying PIZA to PSCz, we are able to obtain the peculiar velocity field, the
dipole, bulk velocities, and the distortion parameter. From the dipole, we find
that beta=0.51+/-0.14. We compare the PSCz bulk velocity with that of Mk III
and conclude that beta=0.5+/-0.15. We compare the PSCz dipole with that of SFI
and find that beta=0.5+/-0.1.

</DOC>
<DOC>
<DOCNO> 120374 </DOCNO>
1-5 micron imaging of 3CRR galaxies: The K-z relation and the geometry


  It has been claimed by Taylor et al. that the low-redshift end of the K-z
relation for radio galaxies is too bright by about half a magnitude due to
contributions from the obscured quasar nuclei. Such a result has major
implications for the use of the K-band Hubble diagram in understanding the
cosmological evolution of radio galaxies. In this paper we present 1-5 micron
imaging data of a nearly-complete sample of low-redshift radio galaxies; this
approach allows us to accurately determine the strengths of any unresolved
nuclear components in the galaxies. We detect nuclear sources in five targets,
whose broad-band colours are consistent with reddened quasar spectra. In all
five cases the ratio of the inferred intrinsic near-infrared luminosity to the
narrow-line luminosity is typical of quasars. We find a correlation between the
inferred nuclear extinction and core-to-lobe ratio, which places constraints on
the geometry of the torus. We find evidence for a shift of the K-z relation to
fainter magnitudes, but by a much smaller amount (~0.1 mag) than Taylor et al.
determined. Under the assumption that the nuclear sources in radio galaxies
have the same intrinsic near-infrared spectra as quasars, our multi-wavelength
images allow us to limit any possible shift to less than 0.3 magnitudes.

</DOC>
<DOC>
<DOCNO> 13494 </DOCNO>
Detection of Single Spin Decoherence in a Quantum Dot via Charge


  We consider a quantum dot attached to leads in the Coulomb blockade regime
which has a spin 1/2 ground state. We show that by applying an ESR field to the
dot-spin the stationary current in the sequential tunneling regime exhibits a
resonance whose line width is determined by the single-spin decoherence time
T_2. The Rabi oscillations of the dot-spin are shown to induce coherent current
oscillations from which T_2 can be deduced in the time domain. We describe a
spin-inverter which can be used to pump current through a double-dot via spin
flips generated by ESR.

</DOC>
<DOC>
<DOCNO> 102245 </DOCNO>
John Bell's Observations on the Chiral Anomaly and Some Properties of


  John Bell's emphasis of the essential ambiguities in anomaly calculations is
recalled. Some descendants of the anomaly are reviewed.

</DOC>
<DOC>
<DOCNO> 8987 </DOCNO>
Diabolical Points in Magnetic Molecules: An Exactly Solvable Model


  The magnetic molecule Fe_8 has been observed to have a rich pattern of
degeneracies in its magnetic spectrum as the static magnetic field applied to
the molecule is varied. The points of degeneracy, or diabolical points in the
magnetic field space, are found exactly in the simplest model Hamiltonian for
this molecule. The points are shown to form a perfect centered rectangular
lattice, and are shown to be multiply diabolical in general. The multiplicity
is found. An earlier semiclassical solution to this problem is thereby shown to
be exact in leading order in 1/J where J is the spin.

</DOC>
<DOC>
<DOCNO> 8253 </DOCNO>
Multiple scattering of light by atoms in the weak localization regime


  Coherent backscattering is a multiple scattering interference effect which
enhances the diffuse reflection off a disordered sample in the backward
direction. Classically, the enhanced intensity is twice the average background
under well chosen experimental conditions. We show how the quantum internal
structure of atomic scatterers leads to a significantly smaller enhancement.
Theoretical results for double scattering in the weak localization regime are
presented which confirm recent experimental observations.

</DOC>
<DOC>
<DOCNO> 71588 </DOCNO>
CP Violation and the Cathedral Builders' Paradigm


  Pointing out the profound and unique nature of CP violation, I sketch its
basic phenomenology, its CKM prescription and QCD technologies relevant for
heavy flavour physics. After emphasizing the paradigmatic character of the
establishment of direct CP violation I turn to the future, namely indirect
searches for New Physics in electric dipole moments, $K_{\mu 3}$ decays and
charm transitions on one hand and in beauty decays on the other; these are
described as exciting adventures with novel challenges not encountered before.

</DOC>
<DOC>
<DOCNO> 119688 </DOCNO>
The Clustering of Colour Selected Galaxies


  We present measurements of the angular correlation function of galaxies
selected from a B_J=23.5 multicolour survey of two 5 degree by 5 degree fields
located at high galactic latitudes. The galaxy catalogue of approximately
400,000 galaxies is comparable in size to catalogues used to determine the
galaxy correlation function at low-redshift. Measurements of the z=0.4
correlation function at large angular scales show no evidence for a break from
a power law though our results are not inconsistent with a break at >15 Mpc.
Despite the large fields-of-view, there are large discrepancies between the
measurements of the correlation function in each field, possibly due to dwarf
galaxies within z=0.11 clusters near the South Galactic Pole.
  Colour selection is used to study the clustering of galaxies z=0 to z=0.4.
The galaxy correlation function is found to strongly depend on colour with red
galaxies more strongly clustered than blue galaxies by a factor of 5 at small
scales. The slope of the correlation function is also found to vary with colour
with gamma=1.8 for red galaxies while gamma=1.5 for blue galaxies. The
clustering of red galaxies is consistently strong over the entire magnitude
range studied though there are large variations between the two fields. The
clustering of blue galaxies is extremely weak over the observed magnitude range
with clustering consistent with r_0=2 Mpc. This is weaker than the clustering
of late-type galaxies in the local Universe and suggests galaxy clustering is
more strongly correlated with colour than morphology. This may also be the
first detection of a substantial low redshift galaxy population with clustering
properties similar to faint blue galaxies.

</DOC>
<DOC>
<DOCNO> 170337 </DOCNO>
A Feynman-Kac Formula for Anticommuting Brownian Motion


  Motivated by application to quantum physics, anticommuting analogues of
Wiener measure and Brownian motion are constructed. The corresponding Ito
integrals are defined and the existence and uniqueness of solutions to a class
of stochastic differential equations is established. This machinery is used to
provide a Feynman-Kac formula for a class of Hamiltonians. Several specific
examples are considered.

</DOC>
<DOC>
<DOCNO> 122301 </DOCNO>
Blazar jets: the spectra


  The radiation observed by blazars is believed to originate from the
transformation of bulk kinetic energy of relativistic jets into random energy.
A simple way to achieve this is to have an intermittent central power source,
producing shells of plasma with different bulk Lorentz factors. These shells
will collide at some distance from the center, producing shocks and then
radiation. This scenario, called internal shock model, is thought to be at the
origin of the gamma-rays observed in gamma-ray bursts and can work even better
in blazars. It accounts for the observed key characteristics of these objects,
including the fact that radiation must be preferentially produced at a few
hundreds of Schwarzschild radii from the center, but continues to be produced
all along the jet. At the kpc scale and beyond, the slowly moving parts of a
(straight) jet can be illuminated by the beamed radiation of the core, while
the fast parts of the jet will see enhanced cosmic microwave radiation. In both
cases the Inverse Compton process can be the dominant radiation process,
leading to a copious production of high energy (X-rays and beyond) radiation in
both radio loud quasars and radio-galaxies.

</DOC>
<DOC>
<DOCNO> 150784 </DOCNO>
Dynamical Casimir Effect and Quantum Cosmology


  We apply the background field method and the effective action formalism to
describe the four-dimensional dynamical Casimir effect. Our picture corresponds
to the consideration of quantum cosmology for an expanding FRW universe (the
boundary conditions act as a moving mirror) filled by a quantum massless GUT
which is conformally invariant. We consider cases in which the static Casimir
energy is repulsive and attractive. Inserting the simplest possible inertial
term, we find, in the adiabatic (and semiclassical) approximation, the
dynamical evolution of the scale factor and the dynamical Casimir stress
analytically and numerically (for SU(2) super Yang-Mills theory). Alternative
kinetic energy terms are explored in the Appendix.

</DOC>
<DOC>
<DOCNO> 70608 </DOCNO>
The Weak OPE and Dimension-eight Operators


  We discuss recent work which identifies a potential flaw in standard
treatments of weak decay amplitudes, including that of epsilon'/epsilon. The
point is that (contrary to conventional wisdom) dimension-eight operators
contribute to weak amplitudes at order G_F alpha_s and without 1/M_W^2
suppression. The effect of dimension-eight operators is estimated to be at the
100% level in a sum rule determination of the operator Q_7^(6) at mu = 1.5 GeV,
suggesting that presently available values of mu are too low to justify the
neglect of these effects.

</DOC>
<DOC>
<DOCNO> 7928 </DOCNO>
Modelling of Si-B-N ceramics


  We present results of computer simulations of amorphous Si3B3N7 ceramics. The
computed pair correlation functions are in agreement with the experimental
results. Regarding the structural properties of the B-N, Si-N and N-Si/B
coordination spheres, our results are in full agreement with experimental data.
We confirm that silicon is tetrahedrally coordinated by nitrogen, and boron is
trigonally planar coordinated by nitrogen. Furthermore we find that the
coordination of nitrogen by the cations is also trigonally planar. Additionally
our results suggest that a significant structural property of these materials
is a heterogenity on a lengthscale of about 0.5nm. The simulation of relaxation
and annealing processes of this new substance indicate the existence of rather
stable BN3 building units, while the SiN4 building units are comparatively
malleable.

</DOC>
<DOC>
<DOCNO> 11924 </DOCNO>
A strong-coupling expansion for the Hubbard model


  We reconsider the strong-coupling expansion for the Hubbard model recently
introduced by Sarker and Pairault {\it et al.} By introducing slave particles
that act as projection operators onto the empty, singly occupied and doubly
occupied atomic states, the perturbation theory around the atomic limit
distinguishes between processes that do conserve or do not conserve the total
number of doubly occupied sites. This allows for a systematic $t/U$ expansion
that does not break down at low temperature ($t$ being the intersite hopping
amplitude and $U$ the local Coulomb repulsion). The fermionic field becomes a
two-component field, which reflects the presence of the two Hubbard bands. The
single-particle propagator is naturally expressed as a function of a $2 \times
2$ matrix self-energy. Furthermore, by introducing a time- and
space-fluctuating spin-quantization axis in the functional integral, we can
expand around a ``non-degenerate'' ground-state where each singly occupied site
has a well defined spin direction (which may fluctuate in time). This formalism
is used to derive the effective action of charge carriers in the lower Hubbard
band to first order in $t/U$. We recover the action of the t-J model in the
spin-hole coherent-state path integral. We also compare our results with those
previously obtained by studying fluctuations around the large-$U$ Hartree-Fock
saddle point.

</DOC>
<DOC>
<DOCNO> 8550 </DOCNO>
Novel Coarsening in the Zero Temperature Dynamics of an Ising Chain with


  This paper has been withdrawn by the authors.

</DOC>
<DOC>
<DOCNO> 8243 </DOCNO>
Quantum transport in ballistic conductors: evolution from conductance


  We study the transport properties of a three dimensional atomic-scale contact
in the ballistic regime. The results for the conductance and related
transmission eigenvalues show how the properties of the ideal semi-infinite
leads (i.e. measuring device) as well as the coupling between the leads and the
conductor influence the transport in a two-probe geometry. We observe the
evolution from conductance quantization to resonant tunneling conductance peaks
upon changing the hopping parameter in the disorder-free tight-binding
Hamiltonian which describes the leads and the coupling to the sample.

</DOC>
<DOC>
<DOCNO> 118101 </DOCNO>
SGRs and AXPs - Magnetars or Young Quark Stars ?


  Recent measurements of the spin-down rates of soft gamma ray repeaters (SGRs)
and anomalous X-ray pulsars (AXPs) have been interpreted as evidence that these
objects are ``magnetars'': neutron stars spinning down by magnetic dipole
radiation, but with a magnetic field two orders of magnitude larger than that
of ordinary neutron stars. We discuss the evidence disfavouring this
interpretation. We argue that, instead, the observations support the hypothesis
that SGRs and AXPs are neutron stars that have suffered a transition into a
denser form of nuclear matter to become, presumably, strange stars or quark
stars. Their gravitational energy release while they are cooling and
contracting can power both their quiescent X-ray emission and their star quakes
which produce `soft' gamma ray bursts.

</DOC>
<DOC>
<DOCNO> 120478 </DOCNO>
The Influence of Interactions and Minor Mergers on the Structure of


  This paper is the first part in our series on the influence of tidal
interactions and minor mergers on the radial and vertical disk structure of
spiral galaxies. We report on the sample selection, our observations, and data
reduction. Surface photometry of the optical and near infrared data of a sample
of 110 highly-inclined/edge-on disk galaxies are presented. This sample
consists of two subsamples of 61 non-interacting galaxies (control sample) and
of 49 interacting galaxies/minor merging candidates. Additionally, 41 of these
galaxies were observed in the near infrared. We show that the distribution of
morphological types of both subsamples is almost indistinguishable, covering
the range between 0 <= T <= 9. An improved, 3-dimensional disk modelling- and
fitting procedure is described in order to analyze and to compare the disk
structure of our sample galaxies by using characteristic parameters. We find
that the vertical brightness profiles of galactic disks respond very sensitive
even to small deviations from the perfect edge-on orientation. Hence,
projection effects of slightly inclined disks may cause substantial changes in
the value of the disk scale height and must therefore be considered in the
subsequent study.

</DOC>
<DOC>
<DOCNO> 99602 </DOCNO>
Level Spacings for Integrable Quantum Maps in Genus Zero


  We consider the eigenvalue pair correlation problem for certain integrable
quantum maps on the 2-sphere. The classical maps are time one maps of
Hamiltonian flows of perfect Morse functions. The quantizations are unitary
operators on spaces of homogeneous holomorphic polynomials of degree N in two
complex variables. There are N eigenphases on the unit circle and the pair
correlation problem is to determine the distribution of spacings between the
eigenphases on the length scale of the mean level spacing. The Berry-Tabor
conjecture says that for generic integrable systems, the spacings distribution
should tend to the Poisson (uniform) limit as N tends to infinity. In this
paper and in its addendum we prove a somewhat weak form of this conjecture: We
define a large class of two parameter families of integrable Hamiltonians, and
prove that for almost all elements of each family the limit pair correlation
function is Poisson. In this paper, we take the limit along a slightly sparse
subsequence of N's; in the addendum we take Cesaro means along the full
seuqence.

</DOC>
<DOC>
<DOCNO> 118933 </DOCNO>
Microlensing Constraints on the Frequency of Jupiter Mass Planets


  Microlensing is the only technique likely, within the next 5 years, to
constrain the frequency of Jupiter-analogs. The PLANET collaboration has
monitored nearly 100 microlensing events of which more than 20 have sensitivity
to the perturbations that would be caused by a Jovian-mass companion to the
primary lens. No clear signatures of such planets have been detected. These
null results indicate that Jupiter mass planets with separations of 1.5-3 AU
occur in less than 1/3 of systems. A similar limit applies to planets of 3
Jupiter masses between 1-4 AU.

</DOC>
<DOC>
<DOCNO> 117130 </DOCNO>
Large Coherence Area Thin-Film Photonic Stop-Band Lasers


  We demonstrate that the shift of the stop band position with increasing
oblique angle in periodic structures results in a wide transverse exponential
field distribution corresponding to strong angular confinement of the
radiation. The beam expansion follows an effective diffusive equation depending
only upon the spectral mode width. In the presence of gain, the beam cross
section is limited only by the size of the gain area. As an example of an
active periodic photonic medium, we calculate and measure laser emission from a
dye-doped cholesteric liquid crystal film.

</DOC>
<DOC>
<DOCNO> 13850 </DOCNO>
An exact correspondence between Quantum Hall Skyrmions and non linear


  We show that the ground states of spin-fermions interacting by a delta
repulsive potential in a strong magnetic field can be put in one to one
correspondence with the solitons of the $S_2$ non linear $\sigma$-model.

</DOC>
<DOC>
<DOCNO> 11590 </DOCNO>
Influence of carbon and nitrogen on electronic structure and hyperfine


  Carbon and nitrogen austenites, modeled by Fe8N and Fe8C superstructures are
studied by full-potential LAPW method. Structure parameters, electronic and
magnetic properties as well as hyperfine interaction parameters are obtained.
Calculations prove that Fe-C austenite can be successfully modeled by ordered
Fe8C superstructure. The results show that chemical Fe-C bond in Fe8C has
higher covalent part than in Fe8N. Detailed analysis of electric field gradient
formation for both systems is performed. The calculation of electric field
gradient allow us to carry out a good interpretation of Moessbauer spectra for
Fe-C and Fe-N systems.

</DOC>
<DOC>
<DOCNO> 117174 </DOCNO>
Superluminal Phenomena and the Quantum Preferred Frame


  Motivated by a number of recent experiments, we discuss in this paper a
speculative but physically admissible form and solutions of effective
Maxwell-like equations describing propagation of electromagnetic field in a
medium which ``feels'' a quantum preferred frame.

</DOC>
<DOC>
<DOCNO> 68432 </DOCNO>
Neutrino and axion emissivities of neutron stars from nucleon-nucleon


  Neutrino and axion production in neutron stars occurs mainly as
bremsstrahlung from nucleon-nucleon (NN) scattering. The energy radiated via
neutrinos or axions is typically very small compared to other scales in the
two-nucleon system. The rate of emission of such "soft" radiation is directly
related to the on-shell NN amplitude, and thereby to the NN experimental data.
This facilitates the model-independent calculation of the neutrino and axion
radiation rates which is presented here. We find that the resultant rates are a
factor of four below earlier estimates based on a one-pion-exchange NN
amplitude.

</DOC>
<DOC>
<DOCNO> 69043 </DOCNO>
Analysis of the Decays B-> \pi \pi and \pi K with QCD Factorization in


  In this work, we calculate the branching ratios and CP asymmetries of the
decays of $B \to \pi \pi$ and $\pi K$ in the frame of QCD factorization in the
heavy quark limit. We also compare the results with the estimates by using
conventional factorization and experimental measurements.

</DOC>
<DOC>
<DOCNO> 100217 </DOCNO>
A notion of rectifiability modeled on Carnot groups


  We introduce a notion of rectifiability modeled on Carnot groups. Precisely,
we say that a subset E of a Carnot group G and N is a subgroup of a Carnot
group N', we say E is N-rectifiable if it is the Lipschitz image of a positive
measure subset of N. We prove two main theorems. First, the property that E is
N-rectifiable, where N is a Carnot group (not merely a subgroup of a Carnot
group), is equivalent to N-approximability and the existence of approximate
tangent cones isomorphic to M almost everywhere in E. Second, we investigate
the rectifiability properties of level sets of Lipschitz functions, f, from the
Heisenberg group to the real numbers. We show that, at almost every point on
almost every level set, the level set if H-approximable and has a unique
approximate tangent cone isomorphic to H where H is a subgroup of the
Hesienberg group.

</DOC>
<DOC>
<DOCNO> 100238 </DOCNO>
Loop-erased walks and total positivity


  We consider matrices whose elements enumerate weights of walks in planar
directed weighted graphs (not necessarily acyclic). These matrices are totally
nonnegative; more precisely, all their minors are formal power series in edge
weights with nonnegative coefficients. A combinatorial explanation of this
phenomenon involves loop-erased walks. Applications include total positivity of
hitting matrices of Brownian motion in planar domains.

</DOC>
<DOC>
<DOCNO> 10632 </DOCNO>
Addendum-erratum to: ``Nonasymptotic critical behavior from field theory


  This note is intended to emphasize the existence of estimated Feynman
integrals in three dimensions for the free energy of the O(1) scalar theory up
to five loops which may be useful for other work. We also correct some
misprints of the published paper.

</DOC>
<DOC>
<DOCNO> 170293 </DOCNO>
Time of arrival in Classical and Quantum Mechanics


  The time of arrival at an arbitrary position in configuration space can be
given as a function of the phase space variables for the Liouville integrable
systems of classical mechanics, but only for them. We review the Jacobi-Lie
transformation that explicitly implements this function of positions and
momenta. We then discuss the recently developed quantum formalism for the time
of arrival. We first analyze the case of free particles in one and three space
dimensions. Then, we apply the quantum version of the Jacobi-Lie transformation
to work out the time of arrival operator in the presence of interactions. We
discuss the formalism and its interpretation. We finish by disclosing the
presence (absence) of "instantaneous" tunneling for thin (thick) barriers.

</DOC>
<DOC>
<DOCNO> 152099 </DOCNO>
New M(atrix)-models for Commutative and Noncommutative Gauge Theories


  We propose a M(atrix) model for N=4 $SU(k)$ Super-Yang-Mills theory
compactified on $T^4$. In this model it is possible to make $T^4$
noncommutative and it is easy to turn on all 6 components of the
noncommutativity on $T^4$. The action of S-duality on the noncommutativity
parameters is also manifest. The M(atrix)-model is given by the large $N$ limit
of a $\sigma$-model on $T^2$ whose target space is the moduli space of $k$
SU(N) instantons on $T^3\times R$. We also propose that the $SU(k)$ 2+1D
$Spin(8)$ theory (the low-energy description of $k$ M2-branes) on $T^3$
corresponds to the large $N$ limit of an integral over the latter instanton
moduli space. The identification is based on the fact that Euclidean wrapped
M2-branes in toroidally compactified M-theory correspond to instantons in the
M(atrix)-model. In the new M(atrix) models, operators with nonzero momentum
along $T^3$ (or $T^4$) correspond to insertions of Wilson lines along a 1-cycle
that is determined by the momentum. Momentum is conserved in the large $N$
limit.

</DOC>
<DOC>
<DOCNO> 80770 </DOCNO>
Examples of overlapping convergent expansions of scaling variables


  We construct series expansions for the scaling variables (which transform
multiplicatively under a renormalization group (RG) transformation) in examples
where the RG flows, going from an unstable (Wilson's) fixed point to a stable
(high-temperature) fixed point, can be calculated numerically. The examples are
Dyson's hierarchical model and a simplified version of it. We provide numerical
evidence that the scaling variables about the two fixed points have overlapping
domain of convergence. We show how quantities such as the magnetic
susceptibility can be expressed in terms of these variables. This procedure
provide accurate analytical expressions both in the critical and
high-temperature region.

</DOC>
<DOC>
<DOCNO> 9523 </DOCNO>
Optimal packing of polydisperse hard-sphere fluids II


  We consider the consequences of keeping the total surface fixed for a
polydisperse system of $N$ hard spheres. In contrast with a similar model (J.
Zhang {\it et al.}, J. Chem. Phys. {\bf 110}, 5318 (1999)), the Percus-Yevick
and Mansoori equations of state work very well and do not show a breakdown. For
high pressures Monte Carlo simulation we show three mechanically stable
polydisperse crystals with either a unimodal or bimodal particle-size
distributions.

</DOC>
<DOC>
<DOCNO> 14015 </DOCNO>
On the Influence of Noise on the Critical and Oscillatory Behavior of a


  Noise induced changes in the critical and oscillatory behavior of a
Prey-Predator system are studied using power spectrum density and Spectral
Amplification Factor (SAF) analysis. In the absence of external noise, the
population densities exhibit three kinds of asymptotic behavior, namely:
Absorbing State, Fixed Point (FP) and an Oscillatory Regime (OR) with a well
defined proper (natural) frequency. The addition of noise destabilizes the FP
phase inducing a transition to a new OR. Surprisingly, it is found that when a
periodic signal is added to the control parameter, the system responds
robustly, without relevant changes in its behavior. Nevertheless, the "Coherent
Stochastic Resonance" phenomenon is found only at the proper frequency. Also, a
method based on SAF allows us to locate very accurately the transition points
between the different regimes.

</DOC>
<DOC>
<DOCNO> 8424 </DOCNO>
Charge localization and phonon spectra in hole doped La2NiO4


  The in-plane oxygen vibrations in La2NiO4 are investigated for several
hole-doping concentrations both theoretically and experimentally via inelastic
neutron scattering. Using an inhomogeneous Hartree-Fock plus RPA numerical
method in a two-dimensional Peierls-Hubbard model, it is found that the doping
induces stripe ordering of localized charges, and that the strong
electron-lattice coupling causes the in-plane oxygen modes to split into two
subbands. This result agrees with the phonon band splitting observed by
inelastic neutron scattering in La2-xSrxNiO4. Predictions of strong
electron-lattice coupling in La2NiO4, the proximity of both oxygen-centered and
nickel-centered charge ordering, and the relation between charged stripe
ordering and the splitting of the in-plane phonon band upon doping are
emphasized.

</DOC>
<DOC>
<DOCNO> 170663 </DOCNO>
The Observer in the Quantum Experiment


  A goal of most interpretations of quantum mechanics is to avoid the apparent
intrusion of the observer into the measurement process. Such intrusion is
usually seen to arise because observation somehow selects a single actuality
from among the many possibilities represented by the wavefunction. The issue is
typically treated in terms of the mathematical formulation of the quantum
theory. We attempt to address a different manifestation of the quantum
measurement problem in a theory-neutral manner. With a version of the two-slit
experiment, we demonstrate that an enigma arises directly from the results of
experiments. Assuming that no observable physical phenomena exist beyond those
predicted by the theory, we argue that no interpretation of the quantum theory
can avoid a measurement problem involving the observer.

</DOC>
<DOC>
<DOCNO> 178760 </DOCNO>
Density Effect on Hadronization of a Quark Plasma


  The hadronization cross section in a quark plasma at finite temperature and
density is calculated in the framework of Nambu--Jona-lasinio model with
explicit chiral symmetry breaking. In apposition to the familiar temperature
effect, the quark plasma at high density begins to hadronize suddenly. It leads
to a sudden and strong increase of final state pions in relativistic heavy ion
collisions which may be considered as a clear signature of chiral symmetry
restoration.

</DOC>
<DOC>
<DOCNO> 119997 </DOCNO>
Intermediate-mass star models with different helium and metal contents


  We present a comprehensive theoretical investigation of the evolutionary
properties of intermediate-mass stars. The evolutionary sequences were computed
from the Zero Age Main Sequence up to the central He exhaustion and often up to
the phases which precede the carbon ignition or to the reignition of the
H-shell which marks the beginning of the thermal pulse phase. The evolutionary
tracks were constructed by adopting a wide range of stellar masses
($3\leq$\msun$\leq15$) and chemical compositions. In order to account for
current uncertainties on the He to heavy elements enrichment ratio, the stellar
models were computed by adopting at Z=0.02 two different He contents (Y=0.27,
0.289) and at Z=0.04 three different He contents (Y=0.29, 0.34, and 0.37). To
supply a homogeneous evolutionary scenario which accounts for young Magellanic
stellar systems the calculations were also extended toward lower metallicities
(Z=0.004, Z=0.01), by adopting different initial He abundances. We evaluated
for both solar (Z=0.02) and super-metal-rich (SMR, Z=0.04) models the
transition mass $M^{up}$ between the stellar structures igniting carbon and
those which develop a full electron degeneracy inside the CO core. This
evolutionary scenario allows us to investigate in detail the properties of
classical Cepheids. In particular, we find that the range of stellar masses
which perform the blue loop during the central He-burning phase narrows when
moving toward metal-rich and SMR structures.

</DOC>
<DOC>
<DOCNO> 123240 </DOCNO>
Numerical Analysis of Magnetic Field Amplification by Turbulence


  We apply a Fourier spectral numerical method to 3D incompressible MHD
turbulence with a magnetic Prandtl number $Pr \geq 1$. We examine the processes
by which an initially weak, large-scale seed magnetic field and an initially
weak, small-scale, impulse-like seed magnetic field are amplified. We find that
in both cases the magnetic energy spectrum grows at all scales. The growth
rates at different amplification stages are analyzed. For a large-scale seed
magnetic field, the magnetic energy density grows as $\sim t^2$ for the first
few turbulence eddy turnover times, followed by a dynamic growth stage, where
nonlinear interactions between different scales of the turbulence contribute to
an exponential growth rate that is largely determined by the turbulence eddy
turnover time. For a seed magnetic field that is initially set up at a small
scale in the turbulence, during the kinematic development stage, the growth
rate of magnetic energy is $\propto 1/\tau_{max}$, where $\tau_{max}$ is the
eddy turnover time of the smallest eddies of the turbulence. The kinematic
growth stage is followed by a dynamic growth stage, where nonlinearity plays
important role. During such dynamic growth stage, the growth rate of total
magnetic energy is determined by both the magnetic energy amplification within
the turbulence inertial range and that within the turbulence dissipation range.

</DOC>
<DOC>
<DOCNO> 80743 </DOCNO>
Percolation and Magnetization for Generalized Continuous Spin Models


  For the Ising model, the spin magnetization transition is equivalent to the
percolation transition of Fortuin-Kasteleyn clusters; this result remains valid
also for the conventional continuous spin Ising model. The investigation of
more general continuous spin models may help to obtain a percolation
formulation for the critical behaviour in SU(2) gauge theory. We therefore
study a broad class of theories, introducing spin distribution functions,
longer range interactions and self-interaction terms. The thermal behaviour of
each model turns out to be in the Ising universality class. The corresponding
percolation formulations are then obtained by extending the Fortuin-Kasteleyn
cluster definition; in several cases they illustrate recent rigorous results.

</DOC>
<DOC>
<DOCNO> 83138 </DOCNO>
On the tractable counting of theory models and its application to belief


  We introduced decomposable negation normal form (DNNF) recently as a
tractable form of propositional theories, and provided a number of powerful
logical operations that can be performed on it in polynomial time. We also
presented an algorithm for compiling any conjunctive normal form (CNF) into
DNNF and provided a structure-based guarantee on its space and time complexity.
We present in this paper a linear-time algorithm for converting an ordered
binary decision diagram (OBDD) representation of a propositional theory into an
equivalent DNNF, showing that DNNFs scale as well as OBDDs. We also identify a
subclass of DNNF which we call deterministic DNNF, d-DNNF, and show that the
previous complexity guarantees on compiling DNNF continue to hold for this
stricter subclass, which has stronger properties. In particular, we present a
new operation on d-DNNF which allows us to count its models under the
assertion, retraction and flipping of every literal by traversing the d-DNNF
twice. That is, after such traversal, we can test in constant-time: the
entailment of any literal by the d-DNNF, and the consistency of the d-DNNF
under the retraction or flipping of any literal. We demonstrate the
significance of these new operations by showing how they allow us to implement
linear-time, complete truth maintenance systems and linear-time, complete
belief revision systems for two important classes of propositional theories.

</DOC>
<DOC>
<DOCNO> 117864 </DOCNO>
New Direct Observational Evidence for Kicks in SNe


  We present an updated list of direct strong evidence in favour of kicks being
imparted to newborn neutron stars. In particular we discuss the new cases of
evidence resulting from recent observations of the X-ray binary Circinus X-1
and the newly discovered binary radio pulsar PSR J1141-6545. We conclude that
the assumption that neutron stars receive a kick velocity at their formation is
unavoidable (van den Heuvel & van Paradijs 1997).

</DOC>
<DOC>
<DOCNO> 101167 </DOCNO>
Homogeneous Lorentz manifolds with simple isometry group


  Let H be a closed, noncompact subgroup of a simple Lie group G, such that G/H
admits an invariant Lorentz metric. We show that if G = SO(2,n), with n > 2,
then the identity component of H is conjugate to the identity component of
SO(1,n). Also, if G = SO(1,n), with n > 2, then the identity component of H is
conjugate to the identity component of SO(1,n-1).

</DOC>
<DOC>
<DOCNO> 117939 </DOCNO>
Observations of the Crab Nebula and its pulsar in the far-ultraviolet


  We present HST/STIS far-UV observations of the Crab nebula and its pulsar.
Broad, blueshifted absorption arising in the nebula is seen in C IV 1550,
reaching about 2500 km/s. This can be interpreted as evidence for a fast outer
shell, and we adopt a spherically symmetric model to constrain the properties
of this. We find that the density appears to decrease outward in the shell. A
lower limit to the mass is 0.3 solar masses with an accompanying kinetic energy
of 1.5EE{49} ergs. A massive 10^{51} erg shell cannot be excluded, but is less
likely if the density profile is much steeper than R^{-4} and the velocity is
<6000 km/s. The observations cover the region 1140-1720 A. With the time-tag
mode of the spectrograph we obtain the pulse profile. It is similar to that in
the near-UV, although the primary peak is marginally narrower. Together with
the near-UV data, and new optical data from NOT, our spectrum of the pulsar
covers the entire region from 1140-9250 A. Dereddening the spectrum gives a
flat spectrum for E(B-V)=0.52, R=3.1. This dereddened spectrum of the Crab
pulsar can be fitted by a power law with spectral index alpha_{\nu} = 0.11 +/-
0.04. The main uncertainty is the amount and characteristics of the interstel-
lar reddening, and we have investigated the dependence of \alpha_{\nu} on
E(B-V) and R. In the extended emission covered by our 25" x 0.5" slit in the
far-UV, we detect C IV 1550 and He II 1640 emission lines from the Crab nebula.
Several interstellar absorption lines are detected toward the pulsar. The Ly
alpha absorption indicates a column density of 3.0+/-0.5\EE{21} cm^{-2} of
neutral hydrogen, which agrees well with our estimate of E(B-V)=0.52 mag. Other
lines show no evidence of severe depletion of metals in atomic gas.

</DOC>
<DOC>
<DOCNO> 100726 </DOCNO>
Quivers, Floer cohomology, and braid group actions


  We consider the derived categories of modules over a certain family A_m of
graded rings, and Floer cohomology of Lagrangian intersections in the
symplectic manifolds which are the Milnor fibres of simple singularities of
type A_m. We show that each of these two rather different objects encodes the
topology of curves on an (m+1)-punctured disc. We prove that the braid group
B_{m+1} acts faithfully on the derived category of A_m-modules and that it
injects into the symplectic mapping class group of Milnor fibers. The
philosophy behind our results is as follows. Using Floer cohomology, one should
be able to associate to the Milnor fibre a triangulated category (its
construction has not been carried out in detail). This triangulated category
should contain a full subcategory which is equivalent, up to a slight
difference in the grading, to the derived category of A_m-modules. The full
embedding would connect the two occurrences of the braid group, thus explaining
the similarity between them.

</DOC>
<DOC>
<DOCNO> 13487 </DOCNO>
Finite-Size Effects and Dynamical Scaling in Two-Dimensional Josephson


  In recent years many groups have used Fisher, Fisher, and Huse (FFH)
dynamical scaling to investigate and demonstrate details of the superconducting
phase transition. Some attention has been focused on two dimensions where the
phase transition is of the Kosterlitz-Thouless-Berezinskii (KTB) type. Pierson
et al. used FFH dynamical scaling almost exclusively to suggest that the
dynamics of the two-dimensional superconducting phase transition may be other
than KTB-like. In this work we investigate the ability of scaling behavior by
itself to yield useful information on the nature of the transition. We simulate
current-voltage (IV) curves for two-dimensional Josephson junction arrays with
and without finite-size-induced resistive tails. We find that, for the
finite-size effect data, the values of the scaling parameters, specifically the
transition temperature and the dynamical scaling exponent z, depend critically
on the magnitude of the contribution that the resistive tails make to the IV
curves. In effect, the values of the scaling parameters depend on the noise
floor of the measuring system.

</DOC>
<DOC>
<DOCNO> 70539 </DOCNO>
pNRQCD: concepts and applications


  Heavy quark bound state systems, mesons and hybrids, are discussed in the
framework of the QCD effective field theory called potential Non-Relativistic
QCD.

</DOC>
<DOC>
<DOCNO> 152590 </DOCNO>
Space-time symmetries and simple superalgebras


  We describe spinors in Minkowskian spaces with arbitrary signature and their
role in the classification of space-time superalgebras and their R-symmetries
in any dimension.

</DOC>
<DOC>
<DOCNO> 118503 </DOCNO>
Counts and Sizes of Galaxies in the Hubble Deep Field - South:


  Science objectives for the Next Generation Space Telescope (NGST) include a
large component of galaxy surveys, both imaging and spectroscopy. The Hubble
Deep Field datasets include the deepest observations ever made in the
ultraviolet, optical and near infrared, reaching depths comparable to that
expected for NGST spectroscopy. We present the source counts, galaxy sizes and
isophotal filling factors of the HDF-South images. The observed integrated
galaxy counts reach >500 galaxies per square arcminute at AB<30. We extend
these counts to faint levels in the infrared using models. The trend previously
seen that fainter galaxies are smaller, continues to AB=29 in the high
resolution HDF-S STIS image, where galaxies have a typical half-light radius of
0.1 arcseconds. Extensive Monte Carlo simulations show that the small measured
sizes are not due to selection effects until >29mag. Using the HDF-S NICMOS
image, we show that galaxies are smaller in the near infrared than they are in
the optical. We analyze the isophotal filling factor of the HDF-S STIS image,
and show that this image is mostly empty sky even at the limits of galaxy
detection, a conclusion we expect to hold true for NGST spectroscopy. At the
surface brightness limits expected for NGST imaging, however, about a quarter
of the sky is occupied by the outer isophotes of AB<30 galaxies. We discuss the
implications of these data on several design concepts of the NGST near-infrared
spectrograph. We compare the effects of resolution and the confusion limit of
various designs, as well as the multiplexing advantages of either multi-object
or full-field spectroscopy. We argue that the optimal choice for NGST
spectroscopy of high redshift galaxies is a multi-object spectrograph (MOS)
with target selection by a micro electro mechanical system (MEMS) device.

</DOC>
<DOC>
<DOCNO> 178787 </DOCNO>
Signature of a Pairing Transition in the Heat Capacity of Finite Nuclei


  The heat capacity of iron isotopes is calculated within the interacting shell
model using the complete $(pf+0g_{9/2})$-shell. We identify a signature of the
pairing transition in the heat capacity that is correlated with the suppression
of the number of spin-zero neutron pairs as the temperature increases. Our
results are obtained by a novel method that significantly reduces the
statistical errors in the heat capacity calculated by the shell model Monte
Carlo approach. The Monte Carlo results are compared with finite-temperature
Fermi gas and BCS calculations.

</DOC>
<DOC>
<DOCNO> 178879 </DOCNO>
Elastic p-3He and n-3H scattering with two- and three-body forces


  We report on a microscopic calculation of n-3H and p-3He scattering employing
the Argonne v_{18} and v_8' nucleon-nucleon potentials with and without
additional three-nucleon force. An R-matrix analysis of the p-3He and n-3H
scattering data is presented. Comparisons are made for the phase shifts and a
selection of measurements in both scattering systems. Differences between our
calculation and the R-matrix results or the experimental data can be attributed
to only two partial waves (3P0 and 3P2). We find the effect of the Urbana IX
and the Texas-Los Alamos three-nucleon forces on the phase shifts to be
negligible.

</DOC>
<DOC>
<DOCNO> 122238 </DOCNO>
Parameter information from nonlinear cosmological fields


  We develop a general formalism for analysing parameter information from
non-Gaussian cosmic fields. The method can be adapted to include the nonlinear
effects in galaxy redshift surveys, weak lensing surveys and cosmic velocity
field surveys as part of parameter estimation. It can also be used as a test of
non-Gaussianity of the Cosmic Microwave Background. Generalising Maximum
Likelihood analysis to second-order, we calculate the nonlinear Fisher
Information matrix and likelihood surfaces in parameter space. To this order we
find that the information content is always increased by including
nonlinearity. Our methods are applied to a realistic model of a galaxy redshift
survey, including nonlinear evolution, galaxy bias, shot-noise and
redshift-space distortions to second-order. We find that including
nonlinearities allows all of the degeneracies between parameters to be lifted.
Marginalised parameter uncertainties of a few percent will then be obtainable
using forthcoming galaxy redshift surveys.

</DOC>
<DOC>
<DOCNO> 84327 </DOCNO>
On geodesic propagators and black hole holography


  One of the most challenging technical aspects of the dualities between string
theory on anti-de Sitter spaces and conformal field theories is understanding
how location in the interior of spacetime is represented in the field theory.
It has recently been argued that the interior of the spacetime can be directly
probed by using intrinsically non-local quantities in the field theory. In
addition, Balasubramanian and Ross [hep-th/9906226] argued that when the
spacetime described the formation of an AdS_3 black hole, the propagator in the
field theory probed the whole spacetime, including the region behind the
horizon. We use the same approach to study the propagator for the BTZ black
hole and a black hole solution with a single exterior region, and show that it
reproduces the propagator associated with the natural vacuum states on these
spacetimes. We compare our result with a toy model of the CFT for the
single-exterior black hole, finding remarkable agreement. The spacetimes
studied in this work are analytic, which makes them quite special. We also
discuss the interpretation of this propagator in more general spacetimes,
shedding light on certain issues involving causality, black hole horizons, and
products of local operators on the boundary.

</DOC>
<DOC>
<DOCNO> 169926 </DOCNO>
Special collision dynamics of massless fermions leading to confinement


  This is a theory for the fundamental structure of nature based on spinors as
unique building blocks. Confinement of the spinors in particles is due uniquely
to the dynamics of the collisions between them. The interaction operator
contains only spin and momentum operators. The eigenfunctions of the
interaction operator have negative as well as positive eigenvalues, limited in
magnitude to the Planck energy. Interactions in one-center particles between
spinors with eigenvalues of different sign tend to bring the energy of the
particle closer to zero.
 At the origin of the energy reduction through interaction is the spin
precession, taking place when two spinors of different type come together. The
model can explain the existence of stable particles and all the known forces,
including gravitation.

</DOC>
<DOC>
<DOCNO> 10702 </DOCNO>
Integrable Ladder t-J Model with Staggered Shift of the Spectral


  The generalization of the Yang-Baxter equations (YBE) in the presence of Z_2
grading along both chain and time directions is presented and an integrable
model of t-J type with staggered disposition along a chain of shifts of the
spectral parameter is constructed. The Hamiltonian of the model is computed in
fermionic formulation. It involves three neighbour site interactions and
therefore can be considered as a zig-zag ladder model. The Algebraic Bethe
Ansatz technique is applied and the eigenstates, along with eigenvalues of the
transfer matrix of the model are found. In the thermodynamic limit, the lowest
energy of the model is formed by the quarter filling of the states by fermions
instead of usual half filling.

</DOC>
<DOC>
<DOCNO> 7885 </DOCNO>
Precision microwave dielectric and magnetic susceptibility measurements


  We analyze microwave cavity perturbation methods, and show that the technique
is an excellent, precision method to study the dynamic magnetic and dielectric
response in the $GHz$ frequency range. Using superconducting cavities, we
obtain exceptionally high precision and sensitivity for measurements of
relative changes. A dynamic electromagnetic susceptibility
$\tilde{\zeta}(T)=\zeta ^{\prime}+i\zeta ^{\prime \prime}$ is introduced, which
is obtained from the measured parameters: the shift of cavity resonant
frequency $\delta f$ and quality factor $Q$. We focus on the case of a
spherical sample placed at the center of a cylindrical cavity resonant in the
$TE_{011}$ mode. Depending on the sample characteristics, the magnetic
permeability $\tilde{\mu}$, the dielectric permittivity $\tilde{\epsilon}$ and
the complex conductivity $\tilde{\sigma}$ can be extracted from
$\tilde{\zeta}_{H}$. A full spherical wave analysis of the cavity perturbation
is given. This analysis has led to the observation of new phenomena in novel
low dimensional materials.

</DOC>
<DOC>
<DOCNO> 71225 </DOCNO>
Exploring skewed parton distribution with polarized target


  I briefly review the physics of skewed parton distributions. Special emphasis
is put on the relevance of target polarization, and on the different roles of
small and of intermediate x_B.

</DOC>
<DOC>
<DOCNO> 80581 </DOCNO>
Cost of Generalised HMC Algorithms for Free Field Theory


  We study analytically the computational cost of the Generalised Hybrid Monte
Carlo (GHMC) algorithm for free field theory. We calculate the autocorrelation
functions of operators quadratic in the fields, and optimise the GHMC momentum
mixing angle, the trajectory length, and the integration stepsize. We show that
long trajectories are optimal for GHMC, and that standard HMC is much more
efficient than algorithms based on the Second Order Langevin (L2MC) or Kramers
Equation. We show that contrary to naive expectations HMC and L2MC have the
same volume dependence, but their dynamical critical exponents are z=1 and
z=3/2 respectively.

</DOC>
<DOC>
<DOCNO> 40568 </DOCNO>
Search for R-parity Violating Decays of Supersymmetric Particles in e+e-


  A search for chargino, neutralino and scalar lepton pair-production in e+e-
collisions at the centre-of-mass energy of 189 GeV is performed under the
assumptions that R-parity is not conserved in decays and only one of the
coupling constants lambda_ijk, lambda'_ijk or lambda''_ijk is non-negligible.
No signal is found in a data sample corresponding to an integrated luminosity
of 176.4 pb-1. Limits on the production cross sections, on the Minimal
Supersymmetric Standard Model parameters and on the masses of the
supersymmetric particles are derived.

</DOC>
<DOC>
<DOCNO> 151860 </DOCNO>
Non-BPS Branes in a Type I Orbifold


  We analyse the spectrum of non-BPS branes in the type I theory on the
orbifold $T^4/{\cal I}_4$. We present a detailed analysis of the action of the
worldsheet parity $\Omega$ on the different D-brane boundary state sectors of
type IIB on $T^4/{\cal I}_4$, using the covariant formulation. Using these
results we derive the spectrum of branes in the type I orbifold. We find
$\Z_2$- and $\Z$- charged non-BPS branes. A study of the stability of these
branes in the type I orbifold is also presented. We find that the type I
non-BPS D-particle and D-instanton remain stable in the orbifold. The
D-particle carries no charge whereas the non-BPS D-instanton can carry twisted
R-R charge.

</DOC>
<DOC>
<DOCNO> 100291 </DOCNO>
Hankel transform via double Hecke algebra


  We use a degeneration of the 1D double affine Hecke algebra and the Dunkl
operator to study systematically nonsymmetric Bessel functions and their
truncations.

</DOC>
<DOC>
<DOCNO> 80694 </DOCNO>
Gauge anomaly cancellations in SU(2)_L \times U(1)_Y Electroweak theory


  We consider the cohomological classification of the 4+2-dimensional
topological field, which is proposed by L\"uscher, for SU(2)_L \times U(1)_Y
electroweak theory. The dependence on the admissible abelian gauge field of
U(1)_Y is determined through topological argument, with SU(2)_L gauge field
fixed as background. We then show the exact cancellation of the local gauge
anomaly of the mixed type {SU(2)_L}^2 \times U(1)_Y at finite lattice spacing,
as well as {U(1)_Y}^3, using the pseudo reality of SU(2)_L and the anomaly
cancellation conditions in the electroweak theory given in terms of the
hyper-charges of U(1)_Y.

</DOC>
<DOC>
<DOCNO> 150679 </DOCNO>
Cutoff dependence of the Casimir effect


  The problem of calculating the Casimir force on two conducting planes by
means of the stress tensor is examined. The evaluation of this quantity is
carried out using an explicit regularization procedure which has its origin in
the underlying (2+1) dimensional Poincar\'{e} invariance of the system. The
force between the planes is found to depend on the ratio of two independent
cutoff parameters, thereby rendering any prediction for the Casimir effect an
explicit function of the particular calculational scheme employed. Similar
results are shown to obtain in the case of the conducting sphere.

</DOC>
<DOC>
<DOCNO> 8370 </DOCNO>
Band-theoretical prediction of magnetic anisotropy in uranium


  Magnetic anisotropy of uranium monochalcogenides, US, USe and UTe, is studied
by means of fully-relativistic spin-polarized band structure calculations
within the local spin-density approximation. It is found that the size of the
magnetic anisotropy is fairly large (about 10 meV/unit formula), which is
comparable with experiment. This strong anisotropy is discussed in view of a
pseudo-gap formation, of which crucial ingredients are the exchange splitting
of U 5f states and their hybridization with chalcogen p states (f-p
hybridization). An anomalous trend in the anisotropy is found in the series
(US>>USe<UTe) and interpreted in terms of competition between localization of
the U 5f states and the f-p hybridization. It is the spin-orbit interaction on
the chalcogen p states that plays an essential role in enlarging the strength
of the f-p hybridization in UTe, leading to an anomalous systematic trend in
the magnetic anisotropy.

</DOC>
<DOC>
<DOCNO> 119085 </DOCNO>
On the Blandford - Znajek mechanism of the energy loss of a rotating


  The Grad--Shafranov approach to the problem of the structure of the black
hole magnetosphere is discussed. For the double transonic flow, the number of
boundary conditions in the pair creation region is shown to be sufficient to
determine not only the longitudinal electric current, but also the angular
velocity of a flow as a solution to a problem. As a result, the energy loss is
determined by the physical parameters at the particle creation region rather
than the "boundary conditions" at the event horizon.

</DOC>
<DOC>
<DOCNO> 85295 </DOCNO>
Analytic derivation of the map of null rays passing near a naked


  Recently the energy emission from a naked singularity forming in spherical
dust collapse has been investigated. This radiation is due to the particle
creation in a curved spacetime. In this discussion, the central role is played
by the mapping formula between the incoming and the outgoing null coordinates.
For the self-similar model, this mapping formula has been derived analytically.
But for the model with $C^{\infty}$ density profile, the mapping formula has
been obtained only numerically. In the present paper, we argue that the
singular nature of the mapping is determined by the local geometry around the
point at which the singularity is first formed. If this is the case, it would
be natural to expect that the mapping formula can be derived analytically. In
the present paper, we analytically rederive the same mapping formula for the
model with $C^{\infty}$ density profile that has been earlier derived using a
numerical technique.

</DOC>
<DOC>
<DOCNO> 151488 </DOCNO>
Nahm's equations, $N=1^*$ domain walls, and D-strings in $AdS_5 x S_5$


  We consider the following two problems: classical domain walls in the $N=1^*$
mass deformation of the maximally supersymmetric Yang Mills theory, and
D-strings as external magnetic sources in the context of the AdS/CFT
correspondence. We show that they are both described by Nahm's equations with
unconventional boundary conditions, and analyze the relevant moduli space of
solutions. We argue that general `fuzzy sphere' configurations of D-strings in
AdS$_5$ correspond to Wilson-'t Hooft lines in higher representations of the
dual SU(n) gauge theory.

</DOC>
<DOC>
<DOCNO> 151111 </DOCNO>
The Ramond-Ramond self-dual Five-form's Partition Function on the Ten


  In view of the recent interest in formulating a quantum theory of
Ramond-Ramond p-forms, we exhibit an SL(10,Z) invariant partition function for
the chiral four-form of Type IIB string theory on the ten-torus. We follow the
strategy used to derive a modular invariant partition function for the chiral
two-form of the M-theory fivebrane. We also generalize the calculation to
self-dual quantum fields in spacetime dimension 2p=2+4k, and display the
SL(2p,Z) automorphic forms for odd p>1. We relate our explicit calculation to a
computation of the B-cycle periods, which are discussed in the work of Witten.

</DOC>
<DOC>
<DOCNO> 120022 </DOCNO>
Giant repeated ejections from GRS 1915+105


  We report simultaneous millimetre and infrared observations of a sequence of
very large amplitude quasi-periodic oscillations from the black hole X-ray
binary GRS 1915+105. These oscillations are near the end of a sequence of over
700 repeated events as observed at 15 GHz, and are simultaneous at the mm and
infrared wavelengths to within our time resolution (<4 min), consistent with
the respective emitting regions being physically close near the base of the
outflow. One infrared event appears to have no mm counterpart, perhaps due to
highly variable absorption. The overall radio-mm-infrared spectrum around the
time of the observations does suggest some absorption at lower frequencies. We
calculate the energy and mass-flow into the outflow for a number of different
assumptions, and find that the time-averaged power required to produce the
observed synchrotron emission cannot be much less than 3e38 erg/s, and is
likely to be much larger. This minimum power requirement is found regardless of
whether the observed emission arises in discrete ejections or in an internal
shock in a quasi-continuous flow. Depending on the similarity of the physical
conditions in the two types of ejection, GRS 1915+105 may be supplying more
power (and mass, if both have the same baryonic component) to the jet during
periods of repeated oscillations than during the more obvious larger events.

</DOC>
<DOC>
<DOCNO> 85054 </DOCNO>
Quantum Computation toward Quantum Gravity


  The aim of this paper is to enlight the emerging relevance of Quantum
Information Theory in the field of Quantum Gravity. As it was suggested by J.
A. Wheeler, information theory must play a relevant role in understanding the
foundations of Quantum Mechanics (the "It from bit" proposal). Here we suggest
that quantum information must play a relevant role in Quantum Gravity (the "It
from qubit" proposal). The conjecture is that Quantum Gravity, the theory which
will reconcile Quantum Mechanics with General Relativity, can be formulated in
terms of quantum bits of information (qubits) stored in space at the Planck
scale. This conjecture is based on the following arguments: a) The holographic
principle, b) The loop quantum gravity approach and spin networks, c) Quantum
geometry and black hole entropy. Here we present the quantum version of the
holographic principle by considering each pixel of area of an event horizon as
a qubit. This is possible if the horizon is pierced by spin networks' edges of
spin 1\2, in the superposed state of spin "up" and spin "down".

</DOC>
<DOC>
<DOCNO> 151421 </DOCNO>
Conformal Fields in Higher Dimensions


  We generalize, to any space-time dimension, the unitarity bounds of highest
weight UIR's of the conformal groups with Lie algebras $so(2,d)$. We classify
gauge theories invariant under $so(2,d)$, both integral and half-integral
spins. A similar analysis is carried out for the algebras $so^*(2n)$. We study
new unitary modules of the conformal algebra in $d>4$, that have no analogue
for $d\leq 4$ as they cannot be obtained by "squaring" singletons. This may
suggest the interpretation of higher dimensional non-trivial conformal field
theories as theories of "tensionless" $p$-branes of which tensionless strings
in $d=6$ are just particular examples.

</DOC>
<DOC>
<DOCNO> 122759 </DOCNO>
Detection of Excess Hard X-ray Emission from the Group of Galaxies HCG62


  From the group of galaxies HCG62, we detected an excess hard X-ray emission
in energies above $\sim 4$ keV with \A SCA. The excess emission is spatially
extended up to $\sim10'$ from the group center, and somewhat enhanced toward
north. Its spectrum can be represented by either a power-law of photon index
0.8-2.7, or a Bremsstrahlung of temperature $>6.3$ keV. In the 2-10 keV range,
the observed hard X-ray flux, $(1.0\pm0.3)\times10^{-12}$ erg cm$^{-2}$
s$^{-1}$, implies a luminosity of $(8.0\pm2.0)\times10^{41}$ erg s$^{-1}$ for a
Hubble constant of 50 km s$^{-1}$ Mpc$^{-1}$. The emission is thus too luminous
to be attributed to X-ray binaries in the memb er galaxies. We discuss possible
origin of the hard X-ray emission.

</DOC>
<DOC>
<DOCNO> 13978 </DOCNO>
Finite temperature numerical renormalization group study of the


  Wilson's numerical renormalization group (NRG) method for the calculation of
dynamic properties of impurity models is generalized to investigate the
effective impurity model of the dynamical mean field theory at finite
temperatures. We calculate the spectral function and self-energy for the
Hubbard model on a Bethe lattice with infinite coordination number directly on
the real frequency axis and investigate the phase diagram for the Mott-Hubbard
metal-insulator transition. While for T<T_c approx 0.02W (W: bandwidth) we find
hysteresis with first-order transitions both at U_c1 (defining the insulator to
metal transition) and at U_c2 (defining the metal to insulator transition), at
T>T_c there is a smooth crossover from metallic-like to insulating-like
solutions.

</DOC>
<DOC>
<DOCNO> 40613 </DOCNO>
Search for the Standard Model Higgs boson in e+e- collisions at root(s)


  The Standard Model Higgs boson is searched for in 233.2 pb-1 of data
collected by the L3 detector at centre of mass energies from 192 GeV to 202
GeV. These data are consistent with the expectations of Standard Model
processes and no evidence of a Higgs signal is observed. A lower limit on the
mass of the Standard Model Higgs boson of 107.0 GeV is set at the 95%
confidence level.

</DOC>
<DOC>
<DOCNO> 169685 </DOCNO>
A model for ensemble NMR quantum computer using antiferromagnetic


  The one-dimensional homonuclear periodic array of nuclear spins I = 1/2,
owing to hyperfine interaction of nuclear spins with electronic magnetic
moments in antiferromagnetic structure, is considered. The neighbor nuclear
spins in such array are opposite oriented and have resonant frequencies
determined by hyperfine interaction constant, applied magnetic field value and
interaction with the left and right nuclear neighbor spins. The resonant
frequencies difference of nuclear spins, when the neighbor spins have different
and the same states, is used to control the spin dynamics by means of selective
resonant RF-pulses both for single nuclear spins and for ensemble of nuclear
spins with the same resonant frequency.
  A model for the NMR quantum computer of cellular-automata type based on an
one-dimensional homonuclear periodic array of spins is proposed. This model may
be generalized to a large ensemble of parallel working one-dimensional arrays
and to two-dimensional and three-dimensional structures.

</DOC>
<DOC>
<DOCNO> 40329 </DOCNO>
Future Atmospheric Neutrino Detectors


  Future experiments focusing on atmospheric neutrino detection are reviewed.
One of the main goals of these experiments is the detection of an unambiguous
oscillation pattern (nu_mu reappearance) to prove the oscillation hypothesis.
Further goals include the discrimination of nu_mu - nu_tau and nu_mu -
nu_sterile oscillations, and the detection of a potential small nu_mu - nu_e
contribution. The search for matter effects in three or more flavour
oscillations can be used to constrain hybrid oscillation models and potentially
measure the sign of delta m^2. The detectors and measurement techniques
proposed to achieve these goals are described, and their physics reach is
discussed.

</DOC>
<DOC>
<DOCNO> 120595 </DOCNO>
Binary Globular Clusters


  The dynamics of a close binary system of globular clusters is considered. It
is shown that the star transfer process from one of the components to the other
should lead to the decrease of dimension of the first cluster with simultaneous
increase of the dimension of the second cluster. The rates of variations of
clusters' sizes due to the mutual tidal interaction between the components, as
well as of the orbital rotation of the binary system on the evolution of
clusters' sizes, are estimated. The results may be attributed to the double
nuclei observed in certain galaxies.

</DOC>
<DOC>
<DOCNO> 102220 </DOCNO>
Rational connectedness and Galois covers of the projective line


  Let k be a p-adic field. Some time ago, D. Harbater [9] proved that any
finite group G may be realized as a regular Galois group over the rational
function field in one variable k(t), namely there exists a finite field
extension $F/k(t)$, Galois with group G, such that F is a regular extension of
k (i.e. k is algebraically closed in F). Moreover, one may arrange that a given
k-place of k(t) be totally split in F. Harbater proved this theorem for k an
arbitrary complete valued field. Rather formal arguments ([10, \S 4.5]; \S2
hereafter) then imply that the theorem holds over any `large' field k. This in
turn is a special case of a result of Pop [15], hence will be referred to as
the Harbater/Pop theorem. We refer to [10], [16], [6] for precise references to
the literature (work of D\`ebes, Deschamps, Fried, Haran, Harbater, Jarden,
Liu, Pop, Serre, and V\"olklein).
  Most proofs (see [10], [19, 8.4.4, p.~93] and Liu's contribution to [16]; see
however [15]) first use direct arguments to establish the theorem when G is a
cyclic group (here the nature of the ground field is irrelevant), then proceed
by patching, using either formal or rigid geometry, together with GAGA
theorems.
  In the present paper, where I take the case of algebraically closed fields
for granted, I show how a technique recently developed by Koll\'ar [12] may be
used to give a quite different proof of the Harbater/Pop theorem, when the
`large' field k has characteristic zero. This proof actually gives more than
the original result (see comment after statement of Theorem 1).

</DOC>
<DOC>
<DOCNO> 71093 </DOCNO>
Contemporary applications of Dyson-Schwinger equations


  We illustrate the contemporary application of Dyson-Schwinger equations using
two examples: the calculation of pseudoscalar meson masses, an associated
model-independent mass formula and the approach to the heavy-quark limit; and
the study of nucleon observables, including a calculation of its mass, $M$, via
a covariant Fadde'ev equation and an estimate of pion-loop contributions to
$M$.

</DOC>
<DOC>
<DOCNO> 170814 </DOCNO>
Non-local Operations: Purification, storage, compression, tomography,


  We provide several applications of a previously introduced isomorphism
between physical operations acting on two systems and entangled states [1]. We
show: (i) how to implement (weakly) non-local two qubit unitary operations with
a small amount of entanglement; (ii) that a known, noisy, non-local unitary
operation as well as an unknown, noisy, local unitary operation can be
purified; (iii) how to perform the tomography of arbitrary, unknown, non-local
operations; (iv) that a set of local unitary operations as well as a set of
non-local unitary operations can be stored and compressed; (v) how to implement
probabilistically two-qubit gates for photons. We also show how to compress a
set of bipartite entangled states locally, as well as how to implement certain
non-local measurements using a small amount of entanglement. Finally, we
generalize some of our results to multiparty systems.

</DOC>
<DOC>
<DOCNO> 69083 </DOCNO>
The Boltzmann equation for colourless plasmons in hot QCD plasma.


  Within the framework of the semiclassical approximation, we derive the
Boltzmann equation describing the dynamics of colorless plasmons in a hot QCD
plasma. The probability of the plasmon-plasmon scattering at the leading order
in the coupling constant is obtained. This probability is gauge-independent at
least in the class of the covariant and temporal gauges. It is noted that the
structure of the scattering kernel possesses important qualitative difference
from the corresponding one in the Abelian plasma, in spite of the fact that we
focused our study on the colorless soft excitations. It is shown that
four-plasmon decay is suppressed by the power of $g$ relative to the process of
nonlinear scattering of plasmons by thermal particles at the soft momentum
scale. It is stated that the former process becomes important in going to the
ultrasoft region of the momentum scale.

</DOC>
<DOC>
<DOCNO> 117066 </DOCNO>
Magnetospheric disturbances, and the GPS operation


  We have investigated a dependence of the relative density of phase slips in
the GPS navigation system on the disturbance level of the Earth's
magnetosphere. The study is based on using Internet-available selected data
from the global GPS network, with the simultaneously handled number of
receiving stations ranging from 160 to 323. The analysis used four days from
the period 1999-2000, with the values of the geomagnetic field disturbance
index Dst from 0 to -300 nT. During strong magnetic storms, the relative
density of phase slips on mid latitudes exceeds the one for magnetically quiet
days by one-two orders of magnitude as a minimum, and reaches a few and (for
some of the GPS satellites) even ten percent of the total density of
observations. Furthermore, the level of phase slips for the GPS satellites
located on the sunward side of the Earth was by a factor of 5-10 larger
compared with the opposite side of the Earth. The high positive correlation of
an increase in the density of phase slips and the intensity of ionospheric
irregularities during geomagnetic disturbances as detected in this study points
to the fact that the increase is slips is caused by the scattering of the GPS
signal from ionospheric irregularities.

</DOC>
<DOC>
<DOCNO> 151969 </DOCNO>
Gauge invariance and background field formalism in the exact


  We discuss gauge symmetry and Ward-Takahashi identities for Wilsonian flows
in pure Yang-Mills theories. The background field formalism is used for the
construction of a gauge invariant effective action. The symmetries of the
effective action under gauge transformations for both the gauge field and the
auxiliary background field are separately evaluated. We examine how the
symmetry properties of the full theory are restored in the limit where the
cut-off is removed.

</DOC>
<DOC>
<DOCNO> 102506 </DOCNO>
On the flatness of local models for the symplectic group


  We investigate the bad reduction of certain Shimura varieties (associated to
the symplectic group). More precisely, we look at a model of the Shimura
variety at a prime p, with parahoric level structure at p. We show that this
model is flat, as conjectured by Rapoport and Zink, and that its special fibre
is reduced.

</DOC>
<DOC>
<DOCNO> 100575 </DOCNO>
The Concept of Particle Weights in Local Quantum Field Theory


  The concept of particle weights has been introduced by Buchholz and the
author in order to obtain a unified treatment of particles as well as (charged)
infraparticles which do not permit a definition of mass and spin according to
Wigner's theory. Particle weights arise as temporal limits of physical states
in the vacuum sector and describe the asymptotic particle content. Following a
thorough analysis of the underlying notion of localizing operators, we give a
precise definition of this concept and investigate the characteristic
properties. The decomposition of particle weights into pure components which
are linked to irreducible representations of the quasi-local algebra has been a
long-standing desideratum that only recently found its solution. We set out two
approaches to this problem by way of disintegration theory, making use of a
physically motivated assumption concerning the structure of phase space in
quantum field theory. The significance of the pure particle weights ensuing
from this disintegration is founded on the fact that they exhibit features of
improper energy-momentum eigenstates, analogous to Dirac's conception, and
permit a consistent definition of mass and spin even in an infraparticle
situation.

</DOC>
<DOC>
<DOCNO> 118721 </DOCNO>
Populations of high-luminosity density-bounded H II regions in spiral


  (Abridged) We present evidence that the HII regions of high luminosity in
disk galaxies may be density bounded, so that a significant fraction of the
ionizing photons emitted by their exciting OB stars escape from the regions.
The key piece of evidence is the presence, in the H\alpha luminosity functions
(LFs) of the populations of HII regions, of glitches, local sharp peaks at an
apparently invariant luminosity, defined as the Stromgren luminosity (L_ Str),
L_H\alpha = L_Str = 10^38.6 (\pm 10^0.1) erg/s (no other peaks are found in any
of the LFs) accompanying a steepening of slope for L_H\alpha> L_Str. This
behavior is readily explicable via a physical model whose basic premises are:
(a) the transition at L_H\alpha = L_Str marks a change from essentially
ionization bounding at low luminosities to density bounding at higher values,
(b) for this to occur the law relating stellar mass in massive star-forming
clouds to the mass of the placental cloud must be such that the ionizing photon
flux produced within the cloud is a function which rises more steeply than the
mass of the cloud. Supporting evidence for the hypothesis of this transition is
presented. If confirmed, the density-bounding hypothesis would imply that the
density-bounded regions were the main sources of the photons which ionize the
diffuse gas in disk galaxies. We estimate that these regions emit sufficient
Lyman continuum not only to ionize the diffuse medium, but to cause a typical
spiral to emit significant ionizing flux into the intergalactic medium. The low
scatter observed in L_Str, less than 0.1 mag rms in the still quite small
sample measured to date, is an invitation to widen the data base, and to
calibrate against primary standards, with the aim of obtaining a precise
standard candle.

</DOC>
<DOC>
<DOCNO> 40614 </DOCNO>
Evidence of New States Decaying into $\Xi^{\prime}_{c}\pi$


  Using 13.7 $fb^{-1}$ of data recorded by the CLEO detector at CESR, we report
evidence for two new charmed baryons: one decaying into $\Xi_c^{0 \prime}\pi^+$
with the subsequent decay $\Xi_c^{0 \prime} \to \Xi_c^0 \gamma$, and its
isospin partner decaying into $\Xi_c^{+ \prime} \pi^-$ followed by
$\Xi_c^{+\prime} \to \Xi_c^+\gamma$. We measure the following mass differences
for the two states: $M(\Xi_c^0 \gamma \pi^+)-M(\Xi_c^0)$=318.2+-1.3+-2.9 MeV,
and $M(\Xi_c^+ \gamma \pi^-)-M(\Xi_c^+)$=324.0+-1.3+-3.0 MeV. We interpret
these new states as the $J^P = 1/2^- \Xi_{c1}$ particles, the charmed-strange
analogs of the $\Lambda_{c1}^+(2593)$.

</DOC>
<DOC>
<DOCNO> 116421 </DOCNO>
A bounded source cannot emit a unipolar electromagnetic wave


  We show that a bounded source cannot produce a unipolar electromagnetic
pulse. As a consequence, there are no three-dimensional electromagnetic
solitons in vacuum.

</DOC>
<DOC>
<DOCNO> 100483 </DOCNO>
A quantum analog of the Poincare-Birkhoff-Witt theorem


  We reduce the basis construction problem for Hopf algebras generated by
skew-primitive semi-invariants to a study of special elements, called
``super-letters,'' which are defined by Shirshov standard words. In this way we
show that above Hopf algebras always have sets of PBW-generators (``hard''
super-letters). It is shown also that these Hopf algebras having not more than
finitely many ``hard'' super-letters share some of the properties of universal
enveloping algebras of finite-dimensional Lie algebras. The background for the
proofs is the construction of a filtration such that the associated graded
algebra is obtained by iterating the skew polynomials construction, possibly
followed with factorization.

</DOC>
<DOC>
<DOCNO> 9507 </DOCNO>
Generalized Numerical Renormalization Group for Dynamical Quantities


  In this paper we introduce a new approach for calculating dynamical
properties within the numerical renormalization group. It is demonstrated that
the method previously used fails for the Anderson impurity in a magnetic field
due to the absence of energy scale separation. The problem is solved by
evaluating the Green function with respect to the reduced density matrix of the
full system, leading to accurate spectra in agreement with the static
magnetization. The new procedure (denoted as DM-NRG) provides a unifying
framework for calculating dynamics at any temperature and represents the
correct extension of Wilson's original thermodynamic calculation.

</DOC>
<DOC>
<DOCNO> 178524 </DOCNO>
Fine structure of alpha decay in odd nuclei


  Using an alpha decay level scheme, an explanation for the fine structure in
odd nuclei is evidenced by taking into account the radial and rotational
couplings between the unpaired nucleon and the core of the decaying system. It
is stated that the experimental behavior of the alpha decay fine structure
phenomenon is directed by the dynamical characteristics of the system.

</DOC>
<DOC>
<DOCNO> 120120 </DOCNO>
Theory of Low-Mass Stars and Substellar Objects


  Since the discovery of the first bona-fide brown dwarfs and extra-solar
planets in 1995, the field of low mass stars and substellar objects has
considerably progressed, both from theoretical and observational
viewpoints.Recent developments in the physics entering the modeling of these
objects have led to significant improvements in the theory and to a better
understanding of their mechanical and thermal properties. This theory can now
be confronted with observations directly in various observational diagrams
(color-color, color-magnitude, mass-magnitude, mass-spectral type), a stringent
and unavoidable constraint which became possible only recently, with the
generation of synthetic spectra. In this paper, we present the current
state-of-the-art general theory of low-mass stars and sub-stellar objects, from
one solar mass to one Jupiter mass, regarding primarily their interior
structure and evolution. This review is a natural complement to the previous
review on the atmosphere of low-mass stars and brown dwarfs (Allard et al
1997). Special attention is devoted to the comparison of the theory with
various available observations. The contribution of low-mass stellar and
sub-stellar objects to the Galactic mass budget is also analysed.

</DOC>
<DOC>
<DOCNO> 80724 </DOCNO>
Do Instantons of the CP(N-1) Model Melt?


  In the two-dimensional CP(N-1) model one can parametrize exact many-instanton
solutions via N `constituents' (called `zindons'). This parameterization
allows, in principle, a complete `melting' of individual instantons. The model
is therefore well suited to study whether dynamics prefers a dilute or a
strongly overlapping ensemble of instantons. We study the statistical mechanics
of instantons both analytically and numerically. We find that at N=2 the
instanton system collapses into zero-size instantons. At N=3,4 we find that
well-isolated instantons are dynamically preferred though 15-25% of instantons
have a considerable overlap with others.

</DOC>
<DOC>
<DOCNO> 12395 </DOCNO>
Shot Noise by Quantum Scattering in Chaotic Cavities


  We have experimentally studied shot noise of chaotic cavities defined by two
quantum point contacts in series. The cavity noise is determined as 1/4*2e|I|
in agreement with theory and can be well distinguished from other contributions
to noise generated at the contacts. Subsequently, we have found that cavity
noise decreases if one of the contacts is further opened and reaches nearly
zero for a highly asymmetric cavity.

</DOC>
<DOC>
<DOCNO> 12439 </DOCNO>
Effective Hamiltonians and dilution effects in kagome and related


  What is the zero-temperature ordering pattern of a Heisenberg antiferromagnet
with large spin length $S$ (and possibly small dilution), on the kagome
lattice, or others built from corner-sharing triangles and tetrahedra? First, I
summarize the uses of effective Hamiltonians to resolve the large ground-state
degeneracy, leading to long-range order of the usual kind. Secondly, I discuss
the effects of dilution, in particular to {\it non}-frustration of classical
ground states, in that every simplex of spins is optimally satisfied. Of three
explanations for this, the most complete is Moessner-Chalker
constraint-counting. Quantum zero-point energy may compete with classical
exchange energy in a diluted system, creating frustration and enabling a
spin-glass state. I suggest that the regime of over 97% occupation is
qualitatively different from the more strongly diluted regime.

</DOC>
<DOC>
<DOCNO> 102855 </DOCNO>
The Penrose transform for compactly supported cohomology


  We present a version of the Penrose transform which relates compactly
supported cohomology on a complex or CR manifold Z to kernels and cokernels of
differential operators on a parameter space X of compact complex submanifolds
of Z.

</DOC>
<DOC>
<DOCNO> 169823 </DOCNO>
Discussion: Are There Material Objects in Bohm's Theory


  Bedard has argued that the 'minimalist' interpretation of Bohm's theory
"do[es] not make sense", essentially because one cannot account for bonding
properties in terms of particles cofigurations alone. I argue that while this
point is correct, the minimalist interpretation never sought to provide such an
explanation (nor is it incumbant upon this interpretation to do so).

</DOC>
<DOC>
<DOCNO> 117193 </DOCNO>
Can zero-point phenomena truly be the origin of inertia?


  A current approach to the problem of inertia suggests that the origin of the
inertial properties of matter is the interaction between matter and vacuum
electromagnetic zero-point radiation. Herein, it is shown that zero-point
phenomena can be treated as the origin of inertia only when one chooses to
ignore the mass-energy content of matter. In the absence of any physical basis
for such a choice, it is concluded that zero-point-induced forces must arise in
addition to the intrinsic inertial properties of ordinary matter.

</DOC>
<DOC>
<DOCNO> 102254 </DOCNO>
Polynomial Heisenberg algebras and higher order supersymmetry


  It is shown that the higher order supersymmetric partners of the harmonic
oscillator Hamiltonian provide the simplest non-trivial realizations of the
polynomial Heisenberg algebras. A linearized version of the corresponding
annihilation and creation operator leads to a Fock representation which is the
same as for the harmonic oscillator Hamiltonian

</DOC>
<DOC>
<DOCNO> 102861 </DOCNO>
A stretched exponential bound on the rate of growth of the number of


  Let M be a compact manifold of dimension at least 2, Diff^r(M) be the space
of C^r diffeomorphisms of M. Define for any diffeomorphism f in Diff^r(M)
number of isolated periodic points of period n by P_n(f)=# {isolated x in M:
f^n(x)=x}. Artin--Mazur proved that for a dense set of diffeomorphisms the
number of periodic points P_n(f) growth at most exponentially fast in n. The
author proved that there is an open set N \subset Diff^r(M) such that for a
Baire generic set of diffeomorphisms the number of periodic points P_n(f)
growth arbitrarily fast.
  Arnold posed a problem: Prove that diffeomorphisms with at most exponential
growth of the number of periodic points in period have probability one. In this
paper we annonce and exhibit key ingredients for a partial solution to Arnold's
problem: we prove that for any epsilon>0 with probability one the number of
periodic points is bounded by a streched exponential estimate
P_n(f)<exp(Cn^{1+epsilon}).

</DOC>
<DOC>
<DOCNO> 13866 </DOCNO>
Degenerate Quantum Gases and Bose-Einstein Condensation


  After a brief historical introduction to Bose-Einstein condensation and Fermi
degeneracy, we discuss theoretical results we have recentely obtained for
trapped degenerate quantum gases by means of a thermal field theory approach.
In particular, by using Gross-Pitaevskii and Bogoliubov-Popov equations, we
consider thermodynamical properties of two Bosonic systems: a gas of Lithium
atoms and a gas of Hydrogen atoms. Finally, we investigate finite-temperature
density profiles of a dilute Fermi gas of Potassium atoms confined in a
harmonic potential.

</DOC>
<DOC>
<DOCNO> 13045 </DOCNO>
Fano resonances as a probe of phase coherence in quantum dots


  In the presence of direct trajectories connecting source and drain contacts,
the conductance of a quantum dot may exhibit resonances of the Fano type. Since
Fano resonances result from the interference of two transmission pathways,
their lineshape (as described by the Fano parameter q) is sensitive to
dephasing in the quantum dot. We show that under certain circumstances the
dephasing time can be extracted from a measurement of q for a single resonance.
We also show that q fluctuates from level to level, and calculate its
probability distribution for a chaotic quantum dot. Our results are relevant to
recent experiments by Goeres et al.

</DOC>
<DOC>
<DOCNO> 7717 </DOCNO>
Models of the Small World: A Review


  It is believed that almost any pair of people in the world can be connected
to one another by a short chain of intermediate acquaintances, of typical
length about six. This phenomenon, colloquially referred to as the ``six
degrees of separation,'' has been the subject of considerable recent interest
within the physics community. This paper provides a short review of the topic.

</DOC>
<DOC>
<DOCNO> 169669 </DOCNO>
To the question of a nonrelativistic wave equation for a system of


  It is shown that the Schr\"{o}dinger nonrelativistic equation of a system of
interacting particles is not a rigorously nonrelativistic equation since it is
based on the implicit assumption of finiteness of the interaction propagation
velocity. For a system of interacting particles, a fully nonrelativistic
nonlinear system of integro-differential equations is proposed. In the case
where the size of the system of particles is of the same order as the Compton
wavelength associated with particles, certain essential differences are shown
to exist as compared with traditional consequences of the nonrelativistic
Schr\"{o}dinger equation.

</DOC>
<DOC>
<DOCNO> 11625 </DOCNO>
Quantum Hall Transition in the Classical Limit


  We study the quantum Hall transition using the density-density correlation
function. We show that in the limit h->0 the electron density moves along the
percolating trajectories, undergoing normal diffusion. The localization
exponent coincides with its percolation value \nu=4/3. The framework provides a
natural way to study the renormalization group flow from percolation to quantum
Hall transition. We also confirm numerically that the critical conductivity of
a classical limit of quantum Hall transition is \sigma_{xx} = \sqrt{3}/4.

</DOC>
<DOC>
<DOCNO> 178834 </DOCNO>
Two-pion decay modes of the N*(1440) in n p -> d pi pi


  A simple model for the n p -> d pi pi reaction has been developed. It is
shown that the deuteron momentum spectra measured at T_n = 795 MeV can be
understood in terms of the Roper excitation and its N pi pi decay modes. A
similar pattern, recently observed in p p -> p p pi+ pi-, can be explained in
the same way.

</DOC>
<DOC>
<DOCNO> 11317 </DOCNO>
Spin-Charge Separation is the Key to the High T_c Cuprates


  We argue that spin charge separation holds the key to the understanding of
high temperature superconductivity.

</DOC>
<DOC>
<DOCNO> 72286 </DOCNO>
The Earth effects on the supernova neutrino spectra


  The Earth effects on the energy spectra of supernova neutrinos are studied.
We analyze numerically the time-integrated energy spectra of neutrino in a
mantle-core-mantle step function model of the Earth's matter density profile.
We consider a realistic frame-work in which there are three active neutrinos
whose mass squared differences and mixings are constrained by the present
understanding of solar and atmospheric neutrinos. We find that the energy
spectra change for some allowed mixing parameters. Especially, the expected
number of events at SNO shows characteristic behavior with respect to energy,
i.e. a great dip and peak. We show that observations of the Earth effect allow
us to identify the solar neutrino solution and to probe the mixing angle
$\theta_{2}$.

</DOC>
<DOC>
<DOCNO> 70240 </DOCNO>
Laser spectroscopy of simple atoms and precision tests of bound state


  We present a brief overview of precision tests of bound state QED and mainly
pay our attention to laser spectroscopy as an appropriate tool for these tests.
We particularly consider different precision tests of bound state QED theory
based on the laser spectroscopy of optical transitions in hydrogen, muonium and
positronium and related experiments.

</DOC>
<DOC>
<DOCNO> 100312 </DOCNO>
A Littlewood-Richardson rule for the K-theory of Grassmannians


  We prove an explicit combinatorial formula for the structure constants of the
Grothendieck ring of a Grassmann variety with respect to its basis of Schubert
structure sheaves. We furthermore relate K-theory of Grassmannians to a
bialgebra of stable Grothendieck polynomials, which is a K-theory parallel of
the ring of symmetric functions.

</DOC>
<DOC>
<DOCNO> 151863 </DOCNO>
On the Canonical c-Function in 4-d Field Theories Possessing


  We study monotonicity and other properties of the canonical c-function
(defined through the correlator of the energy-momentum tensor) in some
holographic duals of 4-d quantum field theories. The canonical c-function and
its derivatives are related to the 5-d Green's function of the dual
supergravity theory. While positivity of the canonical c-function is obvious,
we have not found a general proof of its monotonicity, even though c is
monotonic in the few explicit examples we examine in this paper.

</DOC>
<DOC>
<DOCNO> 169914 </DOCNO>
Entanglements and compound states in quantum information theory


  Quantum entanglements, describing truly quantum couplings, are stu died and
classified from the point of view of quantum compound states. We show that c
lassical-quantum correspondences such as quantum encodings can be treated as
d-entanglements leading to a special class of the separable compound states.
The mutual information of the d-compound and entangled states lead to two di
fferent types of entropies for a given quantum state: the von Neumann entrop y,
which is achieved as the supremum of the information over all d-entanglem ents,
and the dimensional entropy, which is achieved at the standard entangl ement,
the true quantum entanglement, coinciding with a d-entanglement only in the
commutative case. The q-capacity of a quantum noiseless channel, defi ned as
the supremum over all entanglements, is given as the logarithm of the
dimensionality of the input von Neumann algebra. It can double the classical
capacity, achieved as the supremum over all semi-quantum couplings (d-entang
lements, or encodings), which is bounded by the logarithm of the dimensional
ity of a maximal Abelian subalgebra.

</DOC>
<DOC>
<DOCNO> 12171 </DOCNO>
Strong-Coupling Theory for Counter-Ion Distributions


  The Poisson-Boltzmann approach gives asymptotically exact counter-ion density
profiles around charged objects in the weak-coupling limit of low valency and
high temperature. In this paper we derive, using field-theoretic methods, a
theory which becomes exact in the opposite limit of strong coupling. Formally,
it corresponds to a standard virial expansion. Long-range divergences, which
render the virial expansion intractable for homogeneous bulk systems, are shown
to be renormalizable for the case of inhomogeneous distribution functions by a
systematic expansion in inverse powers of the coupling parameter. For a planar
charged wall, our analytical results compare quantitatively with extensive
Monte-Carlo simulations.

</DOC>
<DOC>
<DOCNO> 122258 </DOCNO>
The 35-day cycle in Her X-1 as observational appearance of freely


  A careful analysis of X-ray light curves and pulse profiles of Her X-1
obtained over more than 20 years strongly evidences for free precession of a
magnetized neutron star with rotational axis inclined to the orbital plane as a
central clock underlying the observed 35-day period. Strong asymmetric X-ray
illumination of the optical star atmosphere leads to the formation of gaseous
streams coming out of the orbital plane and forming a tilted accretion disk
around the neutron star. Such a disk precesses due to tidal forces and
dynamical action of gaseous streams from the secondary companion. The locking
of these torques with neutron star precession makes the net disk precession
period to be very close to that of the neutron star free precession.

</DOC>
<DOC>
<DOCNO> 80766 </DOCNO>
Aspects of Chiral Symmetry and the Lattice


  I explore the non-perturbative issues entwining lattice gauge theory,
anomalies, and chiral symmetry. After briefly reviewing the importance of
chiral symmetry in particle physics, I discuss how anomalies complicate lattice
formulations. Considerable information can be deduced from effective chiral
Lagrangians, helping interpret the expectations for lattice models and
elucidating the role of the CP violating parameter $\Theta$. I then turn to a
particularly elegant scheme for exploring this physics on the lattice. This
uses an auxiliary extra space-time dimension, with the physical world being a
four dimensional interface.

</DOC>
<DOC>
<DOCNO> 121234 </DOCNO>
Simulating clusters of galaxies: a brief history of `N' and overmerging


  I review four decades of numerical simulations of galaxy clusters focussing
on the attempts to resolve their internal structure. Overmerging describes the
numerical or physical disruption of dark matter halos within dense
environments. This problem was inherent in simulations prior to 1998 but can be
completely overcome with current algorithms and hardware. We can now resolve
many thousands of subhalos within clusters and we may have converged on their
inner structure, allowing several new tests of the hierarchical structure
formation model and the nature of dark matter.

</DOC>
<DOC>
<DOCNO> 68573 </DOCNO>
Photoproduction of Vector Mesons at Large Transfer


  At forward angles, the cross-sections of photoproduction of vector mesons
($\rho$, $\omega$, and $\phi$) are well accounted for by the exchange of the
Pomeron at high energies, while contributions of $t$ channel exchange of
Reggeons are significant at low energies. At large angles, the impact parameter
becomes small enough to prevent their constituents to build up the exchanged
Reggeons or Pomeron. Two gluon exchange appears to dominate above $-t\simeq 1$
GeV$^2$, especially in the $\phi$ channel.

</DOC>
<DOC>
<DOCNO> 9418 </DOCNO>
Roughness of fracture surfaces


  We study the fracture surface of three dimensional samples through a model
for quasi-static fractures known as Born Model. In particular, we consider the
roughness of this fracture surface. We find for the roughness exponent a value
of 0.5 expected for ``small length scales'' in microfracturing experiments.
Since this corresponds to a slow evolution for the fracture, our simulations
confirm that at small length scales the fracture can be considered as
quasi-static. We also show the isotropy of the roughness exponent on the crack
surface. Finally, considering the crack front, we compute the roughness
exponents for this line for longitudinal and transverse fluctuations. It
results in agreement (0.5) with experimental data, and supports the possible
application of the model of line depinning in the case of long-range
interactions.

</DOC>
<DOC>
<DOCNO> 84945 </DOCNO>
Cosmological scaling solutions of minimally coupled scalar fields in


  We examine Friedmann-Robertson-Walker models in three spacetime dimensions.
The matter content of the models is composed of a perfect fluid, with a
$\gamma$-law equation of state, and a homogeneous scalar field minimally
coupled to gravity with a self-interacting potential whose energy density
red-shifts as $a^{-2 \nu}$, where a denotes the scale factor. Cosmological
solutions are presented for different range of values of $\gamma$ and $\nu$.
The potential required to agree with the above red-shift for the scalar field
energy density is also calculated.

</DOC>
<DOC>
<DOCNO> 9097 </DOCNO>
Ground and excited states of the hydrogen negative ion in strong


  The lowest bound states of the hydrogen negative ion and negative donor
systems in a homogeneous magnetic field are investigated theoretically via a
full configuration interaction approach with an anisotropic Gaussian basis set.
The broad magnetic field regime \gamma=0.0008 - 4000 is covered.
Nonrelativistic total energies, electron detachment energies and transition
wavelengths are presented assuming an infinite nuclear mass. The binding
mechanisms are discussed in detail. The accuracy for the energies is enhanced
significantly compared to previously published data.

</DOC>
<DOC>
<DOCNO> 40240 </DOCNO>
Conventional Beams or Neutrino Factories: The Next Generation of


  The purpose of this paper is to provoke a discussion about the right next
step in accelerator-based neutrino physics. In the next five years many
experiments will be done to determine the neutrino mixing parameters. However,
the small parameters $\theta_{13}\Delta m_{21}^2$, and the CP violating phase
are unlikely to be well determined. Here, I look at the potential of
high-intensity, low-energy, narrow-band conventional neutrino beams to
determine these parameters. I find, after roughly estimating the possible
intensity and purity of conventional neutrino and anti-neutrino beam, that
$\sin^2\theta_{13}$ can be measured if greater than a few parts in ten
thousand, $\Delta m_{21}^2$ can be measured if it is greater than $4\times
10^{-5}$ (eV)$^2$, and the CP violating phase can be measured if it is greater
than 20$^\circ$ and the other parameters are not at their lower bounds. If
these conclusions stand up to more detailed analysis, these experiments can be
done long before a muon storage ring source could be built, and at much less
cost.

</DOC>
<DOC>
<DOCNO> 152526 </DOCNO>
Nonlinear Vector-Tensor Multiplets Revisited


  We give an off-shell formulation of the N=2 supersymmetric new nonlinear
vector-tensor multiplet. Interactions arise in this model as a consequence of
gauging the central charge of the supersymmetry algebra, which in contrast to
previous models with local central charge is achieved without a coupling to a
vector multiplet. Furthermore, we present a new action formula that follows
from coupling the N=2 linear multiplet to the vector-tensor multiplet.

</DOC>
<DOC>
<DOCNO> 8158 </DOCNO>
Tsallis Entropy and the transition to scaling in fragmentation


  By using the maximum entropy principle with Tsallis entropy we obtain a
fragment size distribution function which undergoes a transition to scaling.
This distribution function reduces to those obtained by other authors using
Shannon entropy. The treatment is easily generalisable to any process of
fractioning with suitable constraints.

</DOC>
<DOC>
<DOCNO> 13934 </DOCNO>
Realistic description of electron-energy loss spectroscopy for


  We investigate the electron-energy loss spectrum of one-dimensional undoped
CuO$_{3}$ chains within an extended multi-band Hubbard model and an extended
one-band Hubbard model, using the standard Lanczos algorithm. Short-range
intersite Coulomb interactions are explicitly included in these models, and
long-range interactions are treated in random-phase approximation. The results
for the multi-band model with standard parameter values agree very well with
experimental spectra of Sr$_{2}$CuO$_{3}$. In particular, the width of the main
structure is correctly reproduced for all values of momentum transfer. It is
shown for both models that intersite Coulomb interactions mainly lead to an
energy shift of the spectra. We find no evidence for enhanced intersite
interactions in Sr$_{2}$CuO$_{3}$.

</DOC>
<DOC>
<DOCNO> 120707 </DOCNO>
The He II Emitting Nebula N44C in the LMC: Optical/UV Spectroscopy of


  We present HST spectroscopy and imaging, along with new ground-based
spectroscopy and ROSAT HRI imaging, of the He II emitting nebula N44C and its
ionizing star. A GHRS spectrogram of the ionizing star yields a spectral type
of about O7 for the star. The lack of P Cygni profiles for Si IV and C IV
indicates that the star is not a supergiant. The nebular abundances in the
ionized gas are consistent with average abundances for LMC H II regions, with
the possible exception that nitrogen may be enhanced. Enrichment by a former
evolved companion star is not evident. A long-slit echelle spectrogram in
H-alpha + [N II] shows no evidence for high-velocity gas in N44C. This rules
out high-velocity shocks as the source of the nebular He II emission. A 108 ks
ROSAT HRI image of N44C shows no X-ray point source to a 3-sigma upper limit
L(X) < 10^34 erg s^-1 in the 0.1-2.0 keV band. Based on new measurements of the
electron density in the He II emitting region, we derive recombination
timescales of approximately 20 yrs for He^+2 and approximately 4 yrs for Ne^+4.
If N44C is a fossil X-ray ionized nebula, this places severe constraints on
when the putative X-ray source could have turned off. The presence of strong
[Ne IV] emission in the nebula is puzzling if the ionizing source has turned
off. It is possible the system is related to the Be X-ray binaries, although
the O star in N44C does not show Be characteristics at the present time.
Monitoring of X-rays and He II emission from the nebula, as well as a radial
velocity study of the ionizing star, are needed to fully understand the
emission line spectrum of N44C.

</DOC>
<DOC>
<DOCNO> 119994 </DOCNO>
Time-scales of Radio Emission in PSR J0437-4715 at 327 MHz


  Time-scales of radio emission are studied in PSR J0437-4715 at 327 MHz using
almost half a million periods of high quality data from Ooty Radio Telescope.
The radio emission in this milli second pulsar occurs on a short (s) time-scale
of approximately 0.026 +- 0.001 periods, and on a (l) time-scale that is much
longer than the widths of the components of the integrated profile
(approximately 0.05 periods). The width of the s emission increases with its
increasing relative contribution to the total radio emission. This may provide
constraints for the details of discharge of vacuum gaps above pulsar polar
caps. The s emission occasionally takes place in the form of intense spikes,
which are confined to the main component of the integrated profile for 90 per
cent of the time. The positions of spikes within a component of the integrated
profile have no simple relation to the shape of that component. This may have
impact on the interpretation of the integrated profile components in terms of
independent regions of emission on the polar cap.

</DOC>
<DOC>
<DOCNO> 68487 </DOCNO>
On the effective light-cone QCD-Hamiltonian


  Taking the effective interaction between a quark and an anti-quark from
previous work, the dependendence on a regularization scale is removed in line
with the renormalization group. In order to emphasize the essential point, the
full spinor interaction is replaced by a model which includes only the Coulomb
and the hyperfine interaction. By adjusting the effective quark masses, the
only free parameters of the theory, the mass and the size of the pion are
reproduced, as well as the mass of all other pseudo-scalar mesons. Estimates
for the vector mesons are close to the empirical values. The model exposes
screening rather than strict confinement. The ionization thresholds are in
general much larger than the pion mass.

</DOC>
<DOC>
<DOCNO> 85283 </DOCNO>
Geodesic Deviation in Kaluza-Klein Theories


  We study in detail the equations of the geodesic deviation in
multidimensional theories of Kaluza-Klein type. We show that their
4-dimensional space-time projections are identical with the equations obtained
by direct variation of the usual geodesic equation in the presence of the
Lorentz force, provided that the fifth component of the deviation vector
satisfies an extra constraint derived here.

</DOC>
<DOC>
<DOCNO> 68227 </DOCNO>
Chiral Unitary approach to meson-meson and meson-baryon interactions and


  We report on recent nonperturbative techniques that combine the information
of chiral Lagrangians (with and without resonances) with unitarity in coupled
channels and other requirements of the S-matrix theory of the strong
interactions. As a result, the region of applicability of such techniques is
much larger than the one of Chiral Perturbation Theory allowing one to study
also resonance physics. Applications to meson-meson and meson-baryon
scattering, as well as to problems where pairs of mesons or a meson and a
baryon appear in the initial or final state are shown. Implications in several
nuclear problems are also discussed.

</DOC>
<DOC>
<DOCNO> 69226 </DOCNO>
Cosmological Perturbations in Brane-World Theories: Formalism


  We develop a gauge-invariant formalism to describe metric perturbations in
five-dimensional brane-world theories. In particular, this formalism applies to
models originating from heterotic M-theory. We introduce a generalized
longitudinal gauge for scalar perturbations. As an application, we discuss some
aspects of the evolution of fluctuations on the brane. Moreover, we show how
the five-dimensional formalism can be matched to the known four-dimensional one
in the limit where an effective four-dimensional description is appropriate.

</DOC>
<DOC>
<DOCNO> 85202 </DOCNO>
Topologically massive gravity and black holes in three dimensions


  We obtain a general class of exact solutions to topologically massive gravity
with or without a negative cosmological constant. In the first case, we show
that the solution is supersymmetric and asymptotically approaches the extremal
BTZ black hole solution, while in the latter case it goes to flat space-time.

</DOC>
<DOC>
<DOCNO> 122839 </DOCNO>
Galaxy Formation: Was There A Big Bang Shell?


  The tight correlation of galactic velocity distribution to both luminosity
and its black hole mass and the relation of halo parameters to luminous mass
distribution, can not be due to collapse dynamics. A big bang shell can solve
galaxy formation problems by forming the supermassive black holes necessary to
capture the initial blast wave in a coordinated pattern.

</DOC>
<DOC>
<DOCNO> 11217 </DOCNO>
The Strange Behavior of Critical Branched Polymers


  We find that 2-dimensional (2-D) critical branched polymers with no
impurities conclusively belong to the same universality class as 2-D random
percolation clusters, although pure critical 3-D branched polymers do not
belong to the 3-D percolation universality class. We find, moreover, that the
fractal dimension of critical branched polymers in 2-D is independent of the
presence of a random environment, and explore possible explanations for these
strange results. We also report that when there are no impurities the critical
branching probability in 3-D is bc=3.34e-4 +- 0.16e-4.

</DOC>
<DOC>
<DOCNO> 151946 </DOCNO>
BPS Solitons in M5-Brane Worldvolume Theory with Constant Three-Form


  We study BPS solutions for a self-dual string and a neutral string in
M5-brane worldvolume theory with constant three-form field. We further
generalize such solitons to superpose with a calibrated surface. We also study
a traveling wave on a calibrated surface in the constant three-form field
background.

</DOC>
<DOC>
<DOCNO> 118299 </DOCNO>
An X-ray and optical study of the cluster A33


  We report the first detailed X-ray and optical observations of the
medium-distant cluster A33 obtained with the Beppo-SAX satellite and with the
UH 2.2m and Keck II telescopes at Mauna Kea. The information deduced from X-ray
and optical imaging and spectroscopic data allowed us to identify the X-ray
source 1SAXJ0027.2-1930 as the X-ray counterpart of the A33 cluster. The faint,
$F_{2-10 keV} \approx 2.4 \times 10^{-13} \ergscm2$, X-ray source
1SAXJ0027.2-1930, $\sim 2$ arcmin away from the optical position of the cluster
as given in the Abell catalogue, is identified with the central region of A33.
Based on six cluster galaxy redshifts, we determine the redshift of A33,
$z=0.2409$; this is lower than the value derived by Leir and Van Den Bergh
(1977). The source X-ray luminosity, $L_{2-10 keV} = 7.7 \times 10^{43} \ergs$,
and intracluster gas temperature, $T = 2.9$ keV, make this cluster interesting
for cosmological studies of the cluster $L_X-T$ relation at intermediate
redshifts. Two other X-ray sources in the A33 field are identified. An AGN at
z$=$0.2274, and an M-type star, whose emission are blended to form an extended
X-ray emission $\sim 4$ arcmin north of the A33 cluster. A third possibly
point-like X-ray source detected $\sim 3$ arcmin north-west of A33 lies close
to a spiral galaxy at z$=$0.2863 and to an elliptical galaxy at the same
redshift as the cluster.

</DOC>
<DOC>
<DOCNO> 12825 </DOCNO>
Grain Dynamics in a Two-dimensional Granular Flow


  We have used particle tracking methods to study the dynamics of individual
balls comprising a granular flow in a small-angle two-dimensional funnel. We
statistically analyze many ball trajectories to examine the mechanisms of shock
propagation. In particular, we study the creation of, and interactions between,
shock waves. We also investigate the role of granular temperature and draw
parallels to traffic flow dynamics.

</DOC>
<DOC>
<DOCNO> 117837 </DOCNO>
A time-delay determination from VLA light curves of the CLASS


  We present Very Large Array (VLA) 8.5-GHz light curves of the two lens images
of the Cosmic Lens All Sky Survey (CLASS) gravitational lens B1600+434. We find
a nearly linear decrease of 18-19% in the flux densities of both lens images
over a period of eight months (February-October) in 1998. Additionally, the
brightest image A shows modulations up to 11% peak-to-peak on scales of days to
weeks over a large part of the observing period. Image B varies significantly
less on this time scale. We conclude that most of the short-term variability in
image A is not intrinsic source variability, but is most likely caused by
microlensing in the lens galaxy. The alternative, scintillation by the ionized
Galactic ISM, is shown to be implausible based on its strong opposite frequency
dependent behavior compared with results from multi-frequency WSRT monitoring
observations (Koopmans & de Bruyn 1999). From these VLA light curves we
determine a median time delay between the lens images of 47^{+5}_{-6} d (68%)
or 47^{+12}_{-9} d (95%). We use two different methods to derive the time
delay; both give the same result within the errors. We estimate an additional
systematic error between -8 and +7 d. If the mass distribution of lens galaxy
can be described by an isothermal model (Koopmans, de Bruyn & Jackson 1998),
this time delay would give a value for the Hubble parameter, H_0=57^{+14}_{-11}
(95% statistical) ^{+26}_{-15} (systematic) km/s/Mpc (Omega_m=1 and
Omega_Lambda=0). Similarly, the Modified-Hubble-Profile mass model would give
H_0=74^{+18}_{-15} (95% statistical) ^{+22}_{-22} (systematic) km/s/Mpc. For
Omega_m=0.3 and Omega_Lambda=0.7, these values increase by 5.4%. ... (ABRIDGED)

</DOC>
<DOC>
<DOCNO> 99523 </DOCNO>
Differential Operators on Azumaya algebra and Heisenberg algebra


  We use the definition of differential operators on noncommutative rings given
by V.Lunts and A.Rosenberg to find the differential operators on Azumaya
algebras and the Heisenberg algebras.

</DOC>
<DOC>
<DOCNO> 117538 </DOCNO>
Electromagnetic showers in a strong magnetic field


  We present the results concerning the main shower characteristics in a strong
magnetic field obtained through shower simulation. The processes of magnetic
bremsstrahlung and pair production were taken into account for values of the
parameter $\chi \gg 1$. We compare our simulation results with a recently
developed cascade theory in a strong magnetic field.

</DOC>
<DOC>
<DOCNO> 101354 </DOCNO>
sl(2, C) as a complex Lie algebra and the associated non-Hermitian


  The powerful group theoretical formalism of potential algebras is extended to
non-Hermitian Hamiltonians with real eigenvalues by complexifying so(2,1),
thereby getting the complex algebra sl(2,\C) or $A_1$. This leads to new types
of both PT-symmetric and non-PT-symmetric Hamiltonians.

</DOC>
<DOC>
<DOCNO> 71239 </DOCNO>
Galaxy Dynamics and the Second Peak: Cold Dark Matter?


  The amplitude of the second peak in the angular power spectrum of the cosmic
microwave background radiation is constrained to be small by recent experiments
like Boomerang. This is surprising in the context of the LambdaCDM model, which
predicted a large second peak. However, this result is expected if CDM does not
exist. The observed shape of the power spectrum was accurately predicted
(before the fact) by a model motivated by the surprising recent successes of
the modified dynamics (MOND) hypothesized by Milgrom.

</DOC>
<DOC>
<DOCNO> 121689 </DOCNO>
Can we look inside a dynamo?


  For a simple spherically symmetric mean-field dynamo model we investigate the
possibility of determining the radial dependence of the coefficient $\alpha$.
Growth rates for different magnetic field modes are assumed to be known by
measurement. An evolutionary strategy (ES) is used for the solution of the
inverse problem. Numerically, we find quite different $\alpha$-profiles giving
nearly the same eigenvalues. The ES is also applied to find functions
$\alpha(r)$ yielding zero growth rates for the lowest four magnetic field
modes. Additionally, a slight modification of the ES is utilized for an
''energetic'' optimization of $\alpha^2$-dynamos. The consequences of our
findings for inverse dynamo theory and for the design of future dynamo
experiments are discussed.

</DOC>
<DOC>
<DOCNO> 13812 </DOCNO>
Quasicondensate and superfluid fraction in the 2D charged-boson gas at


  The Bogoliubov - de Gennes equations are solved for the Coulomb Bose gas
describing a fluid of charged bosons at finite temperature. The approach is
applicable in the weak coupling regime and the extent of its quantitative
usefulness is tested in the three-dimensional fluid, for which diffusion Monte
Carlo data are available on the condensate fraction at zero temperature. The
one-body density matrix is then evaluated by the same approach for the
two-dimensional fluid with e^2/r interactions, to demonstrate the presence of a
quasi-condensate from its power-law decay with increasing distance and to
evaluate the superfluid fraction as a function of temperature at weak coupling.

</DOC>
<DOC>
<DOCNO> 69094 </DOCNO>
Decays of the $B_{c}$ Meson in a Relativistic Quark-Meson Model


  The semileptonic decay form factors of the double heavy $B_{c}$ meson provide
a unique opportunity to study the strong interactions between two heavy quarks.
A fully relativistic model, with effective non-local quark-meson interactions,
is used to compute semileptonic decay form factors, for both the $B_{c}$ and a
wide range of other heavy-light mesons. Using these form factors predictions
for decay rates and branching ratios are obtained. The results are compared to
other theoretical approaches and, where available, to experimental results. In
addition the radiative decay of $B^*_{c}$ is discussed.

</DOC>
<DOC>
<DOCNO> 102033 </DOCNO>
Hamiltonian Algebroid Symmetries in W-gravity and Poisson sigma-model


  Starting from a Lie algebroid ${\cal A}$ over a space V we lift its action
to the canonical transformations on the principle affine bundle ${\cal R}$ over
the cotangent bundle $T^*V$. Such lifts are classified by the first cohomology
$H^1({\cal A})$. The resulting object is the Hamiltonian algebroid ${\cal A}^H$
over ${\cal R}$ with the anchor map from $\G({\cal A}^H)$ to Hamiltonians of
canonical transformations. Hamiltonian algebroids generalize the Lie algebras
of canonical transformations. We prove that the BRST operator for ${\cal A}^H$
is cubic in the ghost fields as in the Lie algebra case. To illustrate this
construction we analyze two topological field theories. First, we define a Lie
algebroid over the space $V_3$ of $\SL$-opers on a Riemann curve $\Si_{g,n}$ of
genus g with n marked points. The sections of this algebroid are the second
order differential operators on $\Si_{g,n}$. The algebroid is lifted to the
Hamiltonian algebroid over the phase space of $W_3$-gravity. We describe the
BRST operator leading to the moduli space of $W_3$-gravity. In accordance with
the general construction the BRST operator is cubic in the ghost fields. We
present the Chern-Simons explanation of our results. The second example is the
Hamiltonian algebroid structure in the Poisson sigma-model invoked by Cattaneo
and Felder to describe the Kontsevich deformation quantization formula. The
hamiltonian description of the Poisson sigma-model leads to the Lie algebraic
form of the BRST operator.

</DOC>
<DOC>
<DOCNO> 178412 </DOCNO>
Hadrons in Dense Resonance-Matter: A Chiral SU(3) Approach


  A nonlinear chiral SU(3) approach including the spin 3/2 decuplet is
developed to describe dense matter. The coupling constants of the baryon
resonances to the scalar mesons are determined from the decuplet vacuum masses
and SU(3) symmetry relations. Different methods of mass generation show
significant differences in the properties of the spin-3/2 particles and in the
nuclear equation of state.

</DOC>
<DOC>
<DOCNO> 10172 </DOCNO>
Enhanced Spin Polarization of Conduction Electrons in Ni, explained by


  The spin-split Fermi level crossings of the conduction band in Ni are mapped
out by high-resolution photoemission and compared to the equivalent crossing
in Cu. The area of the quasiparticle peak decreases rapidly below Ef in Ni, but
not in Cu. Majority spins have larger spectral weight at Ef than minority
spins, thereby enhancing the spin-polarization beyond that expected from the
density of states. A large part of the effect can be traced to a rapid
variation of the matrix element with {\bf k} at the point where the s,p-band
begins to hybridize with the $dz^2$ state. However, it is quite possible that
the intensity drop in Ni is reinforced by a transfer of spectral weight from
single-particle to many-electron excitations. The results suggest that the
matrix element should be considered for explaining the enhanced spin
polarization observed for Ni in spin-polarized tunneling.

</DOC>
<DOC>
<DOCNO> 151284 </DOCNO>
Noncommutative Tachyons And String Field Theory


  It has been shown recently that by turning on a large noncommutativity
parameter, the description of tachyon condensation in string theory can be
drastically simplified. We reconsider these issues from the standpoint of
string field theory, showing that, from this point of view, the key fact is
that in the limit of a large B-field, the string field algebra factors as the
product of an algebra that acts on the string center of mass only and an
algebra that acts on all other degrees of freedom carried by the string.

</DOC>
<DOC>
<DOCNO> 84569 </DOCNO>
Warm inflation: Towards a realistic COBE data power spectrum for matter


  I consider the COBE data coarse-grained field that characterize the now
observable universe for a model of warm inflation which takes into account the
thermal coupled fluctuations of the scalar field with the thermal bath. The
power spectrum for both, matter and metric fluctuations are analyzed. I find
that the amplitude for the fluctuations of the metric when the horizon entry,
should be very small for the expected values of temperature.

</DOC>
<DOC>
<DOCNO> 39857 </DOCNO>
Implications of Supersymmetry Phases for Higgs Boson Signals and Limits


  We study the supersymmetry parameter region excluded if no Higgs is found at
LEP, and the region allowed if a Higgs boson is found at LEP. We describe the
full seven parameter structure of Higgs sector. When supersymmetry phases are
included, $\tan \beta$ greater than or equal to 2 is always allowed, and the
lower limit on lightest Higgs mass if no signal is found is about 20% lower
than in the Standard Model and about 10% lower than in the MSSM with phases set
to 0, $\pi$

</DOC>
<DOC>
<DOCNO> 101358 </DOCNO>
The Generalized Star Product and the Factorization of Scattering


  In this article we continue our analysis of Schr\"odinger operators on
arbitrary graphs given as certain Laplace operators. In the present paper we
give the proof of the composition rule for the scattering matrices. This
composition rule gives the scattering matrix of a graph as a generalized star
product of the scattering matrices corresponding to its subgraphs. We perform a
detailed analysis of the generalized star product for arbitrary unitary
matrices. The relation to the theory of transfer matrices is also discussed.

</DOC>
<DOC>
<DOCNO> 9168 </DOCNO>
Charge Order in NaV2O5 studied by EPR


  We present angular dependent EPR measurements in NaV2O5 at X-band frequencies
in the temperature range 4.2 K < T < 670 K. A detailed analysis in terms of the
antisymmetric Dzyaloshinski-Moriya and the anisotropic exchange interactions
yields the following scheme of charge order: On decreasing temperature a
quarter-filled ladder with strong charge disproportions, existing for T > 100
K, is followed by zig-zag charge-order fluctuations which become long-range and
static below T_SP=34 K.

</DOC>
<DOC>
<DOCNO> 12491 </DOCNO>
Mechanism of magnetism in stacked nanographite: Theoretical study


  Nanographite systems, where graphene sheets of the orders of the nanometer
size are stacked, show novel magnetic properties, such as, spin-glass like
behaviors and the change of ESR line widths in the course of gas adsorptions.
We theoretically investigate stacking effects in the zigzag nanographite sheets
by using a tight binding model with the Hubbard-like onsite interactions. We
find a remarkable difference in the magnetic properties between the simple A-A
and A-B type stackings. For the simple stacking, there are not magnetic
solutions. For the A-B stacking, we find antiferromagnetic solutions for strong
onsite repulsions. The local magnetic moments tend to exist at the edge sites
in each layer due to the large amplitude of wavefunctions at these sites.
Relations with experiments are discussed.

</DOC>
<DOC>
<DOCNO> 152435 </DOCNO>
Noether and topological currents equivalence and soliton/particle


  A submodel of the so-called conformal affine Toda model coupled to the matter
field (CATM) is defined such that its real Lagrangian has a positive-definite
kinetic term for the Toda field and a usual kinetic term for the (Dirac) spinor
field. After spontaneously broken the conformal symmetry by means of BRST
analysis, we end up with an effective theory, the off-critical affine Toda
model coupled to the matter (ATM). It is shown that the ATM model inherits the
remarkable properties of the general CATM model such as the soliton solutions,
the particle/soliton correspondence and the equivacence between the Noether and
topological currents. The classical solitonic spectrum of the ATM model is also
discussed.

</DOC>
<DOC>
<DOCNO> 39644 </DOCNO>
A Prototype RICH Detector Using Multi-Anode Photo Multiplier Tubes and


  The performance of a prototype Ring Imaging Cherenkov Detector is studied
using a charged particle beam. The detector performance, using CF4 and air as
radiators, is described. Cherenkov angle precision and photoelectron yield
using hybrid photo-diodes and multi-anode PMTs agree with simulations and are
assessed in terms of the requirements of the LHCb experiment.

</DOC>
<DOC>
<DOCNO> 84599 </DOCNO>
The bar-mode instability in differentially rotating neutron stars:


  We study the dynamical stability against bar-mode deformation of rapidly
spinning neutron stars with differential rotation. We perform fully
relativistic 3D simulations of compact stars with $M/R \geq 0.1$, where $M$ is
the total gravitational mass and $R$ the equatorial circumferential radius. We
adopt an adiabatic equation of state with adiabatic index $\Gamma=2$. As in
Newtonian theory, we find that stars above a critical value of $\beta \equiv
T/W$ (where $T$ is the rotational kinetic energy and $W$ the gravitational
binding energy) are dynamically unstable to bar formation. For our adopted
choices of stellar compaction and rotation profile, the critical value of
$\beta = \beta_{dGR}$ is $\sim 0.24-0.25$, only slightly smaller than the
well-known Newtonian value $\sim 0.27$ for incompressible Maclaurin spheroids.
The critical value depends only very weakly on the degree of differential
rotation for the moderate range we surveyed. All unstable stars form bars on a
dynamical timescale. Models with sufficiently large $\beta$ subsequently form
spiral arms and eject mass, driving the remnant to a dynamically stable state.
Models with moderately large $\beta \gtrsim \beta_{dGR}$ do not develop spiral
arms or eject mass but adjust to form dynamically stable ellipsoidal-like
configurations. If the bar-mode instability is triggered in supernovae collapse
or binary neutron star mergers, it could be a strong and observable source of
gravitational waves. We determine characteristic wave amplitudes and
frequencies.

</DOC>
<DOC>
<DOCNO> 118730 </DOCNO>
On the formation and evolution of the globular cluster Omega Centauri


  By means of N-body/hydrodynamical simulations we model the evolution of a
primordial 10^{8} solar masses density peak which ends up in an object closely
resembling the present day globular cluster Omega Centauri. We succeed to
reproduce the main features of the cluster, namely the structure, kinematics
and metallicity distribution. We suggest that Omega Centauri might be a
cosmological dwarf elliptical, formed at high redshift, evolved in isolation
and self-enriched, and eventually fallen inside the potential well of the Milky
Way, in agreement with the Searle-Zinn (1978) paradigm for galactic globular
clusters formation. We finally suggest that Omega Centauri is probably
surrounded by an extended Dark Matter (DM) halo, for which no observational
evidence is at present available. We expect that signatures, if any, of the DM
halo can be found in the kinematics of stars outside about 20 arcmin.

</DOC>
<DOC>
<DOCNO> 40079 </DOCNO>
Resonance Formation in Two-Photon Collisions


  Two-photon collisions at the e$^+$e$^-$ colliders allow to investigate the
formation and the properties of resonant states in a very clean experimental
environment. A remarkable number of new results have been recently obtained
giving important contributions to meson spectroscopy and glueball searches. The
most recent results from the LEP collider at CERN and CESR at Cornell are
reviewed here.

</DOC>
<DOC>
<DOCNO> 119985 </DOCNO>
The Highest Redshift Radio Galaxies


  At low redshifts powerful radio sources are uniquely associated with massive
galaxies, and are thought to be powered by supermassive black holes. Modern 8m
-- 10m telescopes may be used used to find their likely progenitors at very
high redshifts to study their formation and evolution.

</DOC>
<DOC>
<DOCNO> 152572 </DOCNO>
Global p-Brane World: A New Approach to Stable Mass Hierarchy


  We find a class of extremal black hole-like global p-brane in
higher-dimensional gravity with a negative cosmological constant. The region
inside the p-brane horizon possesses all essential features required for the
Randall-Sundrum-type brane world scenario. The set-up allows to interpret the
horizon size as the compactification size in that the Planck scale is
determined by the fundamental scale M* and the horizon size r_H via the
familiar relation M_Pl^2 ~ M*^{2+n} r_{H}^n, and the gravity behaves as
expected in a world with n-extra dimensions compactified with size r_H. Most
importantly, a stable mass hierarchy between M_Pl and M* can be generated from
topological charge of the p-brane and the horizon size r_H therein. We also
offer a new perspective on various issues associated to the brane world
scenarios including the cosmological constant problem.

</DOC>
<DOC>
<DOCNO> 152081 </DOCNO>
Quasilumps from first order phase transitions


  We investigated the bubble collisions during the first order phase
transitions. Numerical results indicate that within the certain range of
parameters the collision of two bubbles leads to formation of separate
relatively long-lived quasilumps - configurations filled with scalar field
oscillating around the true vacuum state. Energy is perfectly localized, and
density is slightly pulsating around its maximum. This process is accompanied
by radiation of scalar waves.

</DOC>
<DOC>
<DOCNO> 101105 </DOCNO>
Clebsch-Gordan and Racah-Wigner coefficients for a continuous series of


  The decomposition of tensor products of representations into irreducibles is
studied for a continuous family of integrable operator representations of
$U_q(sl(2,R)$. It is described by an explicit integral transformation involving
a distributional kernel that can be seen as an analogue of the Clebsch-Gordan
coefficients. Moreover, we also study the relation between two canonical
decompositions of triple tensor products into irreducibles. It can be
represented by an integral transformation with a kernel that generalizes the
Racah-Wigner coefficients. This kernel is explicitly calculated.

</DOC>
<DOC>
<DOCNO> 71045 </DOCNO>
Spectral distortion of cosmic background radiation by scattering on hot


  The spectral distortion of the cosmic background radiation produced by the
inverse Compton scattering on hot electrons in clusters of galaxies (thermal
Sunyaev-Zeldovich effect) is calculated for arbitrary optical depth and
electron temperature. The distortion is found by a numerical solution of the
exact Boltzmann equation for the photon distribution function. In the limit of
small optical depth and low electron temperature our results confirm the
previous analyses. In the opposite limits, our method is the only one that
permits to make accurate calculations.

</DOC>
<DOC>
<DOCNO> 117620 </DOCNO>
Interpretation of the OGLE Q2237+0305 microlensing light-curve


  The four bright images of the gravitationally lensed quasar Q2237+0305 are
being monitored from the ground (eg. OGLE collaboration, Apache Point
Observatory) in the hope of observing a high magnification event (HME). Over
the past three seasons (1997-1999) the OGLE collaboration has produced
microlensing light-curves with unprecedented coverage. These demonstrate
smooth, independent (therefore microlensing) variability between the images
(Wozniak et al. 2000a,b; OGLE web page). We have retrospectively compared
probability functions for high-magnification event parameters with several
observed light-curve features. We conclude that the 1999 image C peak was due
to the source having passed outside of a cusp rather than to a caustic
crossing. In addition, we find that the image C light-curve shows evidence for
a caustic crossing between the 1997 and 1998 observing seasons involving the
appearance of new critical images. Our models predict that the next image C
event is most likely to arrive 500 days following the 1999 peak, but with a
large uncertainty (100-2000 days). Finally, given the image A light-curve
derivative at the end of the 1999 observing season, our modelling suggests that
a caustic crossing will occur between the 1999 and 2000 observing seasons,
implying a minimum for the image A light-curve ~1-1.5 magnitudes fainter than
the November 1999 level.

</DOC>
<DOC>
<DOCNO> 119205 </DOCNO>
Orbits in a Neighboring Dwarf Galaxy According to MOND


  We study the orbits in the MOND theory within a dwarf galaxy of mass Md at a
distance of ~100kpc from a neighboring galaxy of mass Mg, such as ours. It is
assumed that a second mass m<<Md is gravitationally bound to Md by a previously
calculated potential for the MOND theory. This potential is obtained for a free
falling mass Md in a constant external gravitational acceleration field. The
numerical technique of surfaces of section is used to study the stability of
the phase-space orbits in the dwarf galaxy. Equatorial orbits with sufficiently
small eccentricities e<0.65 are found to be stable with respect to small chang
es in the initial conditions. (The equatorial plane is perpendicular to the
direction of the external gravitational acceleration, which is along the line
joining Md and Mg.) For decreasing values of the conserved component of the
angular momentum, in the direction of the external gravitational acceleration,
equatorial stability is lost.

</DOC>
<DOC>
<DOCNO> 11692 </DOCNO>
A new approach to the ground state of quantum-Hall systems. I. Basic


  I present a new approach to the many-body ground state of quantum-Hall
systems. The method describes the behavior of a two-dimensional electron system
at all Landau-level filling factors $\nu$, continuously as a function of
magnetic field, and enables one to analytically calculate any physical value,
characterizing the system, at all $\nu$. New proposed trial many-body wave
functions have a clear physical meaning and a very large variational freedom,
which opens up wide possibilities to search for the ground state of the system
at all magnetic fields.

</DOC>
<DOC>
<DOCNO> 12776 </DOCNO>
Nonperturbative Quantization of the Cylindrically Symmetric Strongly


  A recent investigation of SU(2) Yang-Mills theory found several classical
solutions with bad behaviour at infinity : one of the potential components
oscillated and another tended to infinity. In this paper we apply an idea due
to Heisenberg about the quantization of strongly interacting nonlinear fields
to these classical singular solutions. We find that this quantization procedure
eliminates the bad long distance features while retaining the interesting short
distance aspects of these solutions.

</DOC>
<DOC>
<DOCNO> 117037 </DOCNO>
New schemes for manipulating quantum states using a Kerr cell


  In this proceeding we describe various proposals of application of an high
coefficient Kerr cell to quantum states manipulation, ranging from fast
modulation of quantum interference, GHZ states generation, Schroedinger cats
creation, translucent eavesdropping, etc.

</DOC>
<DOC>
<DOCNO> 69922 </DOCNO>
New Constraints on inflation from the Cosmic Microwave Background


  The recent data from the Boomerang and MAXIMA-1 balloon flights have marked
the beginning of the precision era of Cosmic Microwave Background anisotropy
(CMB) measurements. We investigate the observational constraints from the
current CMB anisotropy measurements on the simplest inflation models,
characterized by a single scalar field $\phi$, in the parameter space
consisting of scalar spectral index $n_S$ and tensor/scalar ratio $r$. If we
include constraints on the baryon density from big bang nucleosynthesis (BBN),
we show that the favored inflationary models have negligible tensor amplitude
and a ``red'' tilt, with a best fit of $n_S \simeq 0.93$, which is consistent
with the simplest ``small-field'' inflation models, but rules out large-field
models at the $1\sigma$ level. Without including BBN constraints, a broader
range of models are consistent with the data. The best fit (assuming negligible
reionization) is a scale-invariant spectrum, $n_S \simeq 1$, which includes
large-field and hybrid scenarios. Large-field models (such as chaotic and
power-law inflation) with tilt $n_S < 0.9$ are strongly disfavored in all
cases.

</DOC>
<DOC>
<DOCNO> 170786 </DOCNO>
Implementation of a quantum algorithm to solve Bernstein-Vazirani's


  Bernstein and Varizani have given the first quantum algorithm to solve parity
problem in which a strong violation of the classical imformation theoritic
bound comes about. In this paper, we refine this algorithm with fewer resource
and implement a two qubits algorithm in a single query on an ensemble quantum
computer for the first time.

</DOC>
<DOC>
<DOCNO> 99882 </DOCNO>
On the Intersection of Two Plane Curves


  We study the following question: fix a sufficient general curve D of degree d
in P^2, what is the least number of intersections between D and an irreducible
curve of degree m? G. Xu proved this number i(d, m) is at least d - 2 for all
m. This problem can be regarded as the algebraic part of Kobayashi conjecture
on the hyperbolicity of P^2 D. We first improved Xu's bound with m fixed and
then generalized his result to rational ruled surfaces.

</DOC>
<DOC>
<DOCNO> 121981 </DOCNO>
Variability Modes of Blazars from Intensive Optical Monitoring


  We report the main results of our six year long intensive optical monitoring
on blazars ON 231 (W Com), BL Lac, and 3C 273. Intensive optical monitoring is
an indispensable tool to obtain well sampled light curves and thus to
understand the correlation with the variability in other bands and to
discriminate among the proposed emission models. The curves based on our work
show different variability modes: intermittent mode, quasi-regular mode and
mixed mode. It is not clear if different variability modes can be present, at
various times, in the life of an object suggesting that their occurrence can be
related to the evolution of blazars. An optimized and nearly continuous optical
monitoring is the only way to know the activity status of the sources and to
retrieve useful information on their physical dynamics. Also, the rapid
availability of information about the luminosity of a source is very important
to trigger space based observations and to activate large multifrequency
collaborations. We stress that a significant sample of blazars can be observed
with small size telescopes (0.35-0.80 cm) equipped with CCD cameras. A
world-wide network of several instruments in different countries, is very
useful to increase the time coverage and to reduce the number of nights lost
for bad meteorological conditions.

</DOC>
<DOC>
<DOCNO> 84500 </DOCNO>
The "Swiss cheese" cosmological model has no extrinsic curvature


  Contrary to a claim, the Schwarzschild solution insertion in an expanding
universe model, the so called "Swiss cheese" model, does not possess an
extrinsic curvature discontinuity. We show that both the intrinsic metric and
the extrinsic curvature are continuous, and point out the error that led to the
claim.

</DOC>
<DOC>
<DOCNO> 118344 </DOCNO>
Detection of X-ray pulsations from the Be/X-ray transient A 0535+26


  Using the RossiXTE experiment, we detect weak X-ray emission from the
recurrent Be/X-ray transient A 0535+26 at a time when the optical counterpart
V725 Tau displayed H-alpha in absorption, indicating the absence of a
circumstellar disc. The X-ray radiation is strongly modulated at the 103.5-s
pulse period of the neutron star, confirming that it originates from A 0535+26.
The source is weaker than in previous quiescence detections by two orders of
magnitude and should be in the centrifugal inhibition regime. We show that the
X-ray luminosity cannot be due to accretion on to the magnetosphere of the
neutron star. Therefore this detection represents a new state of the accreting
pulsar. We speculate that the X-ray emission can be due to some matter leaking
through the magnetospheric barrier or thermal radiation from the neutron star
surface due to crustal heating. The observed luminosity is probably compatible
with recent predictions of thermal radiation from X-ray transients in
quiescence. The detection of the X-ray source in the inhibition regime implies
a reduced density in the outflow from the Be companion during its disc-less
phase.

</DOC>
<DOC>
<DOCNO> 10598 </DOCNO>
Magnetization profiles and NMR spectra of doped Haldane chains at finite


  Open segments of S=1 antiferromagnetic spin chains are studied at finite
temperatures and fields using continuous time Quantum Monte Carlo techniques.
By calculating the resulting magnetization profiles for a large range of chain
lengths with fixed field and temperature we reconstruct the experimentally
measured NMR spectrum of impurity doped Y$_2$BaNi$_{1-x}$Mg$_x$O$_5$. For
temperatures above the gap the calculated NMR spectra are in excellent
agreement with the experimental results, confirming the existence of $S=1/2$
excitations at the end of open S=1 chain segments. At temperatures below the
gap, neglecting inter chain couplings, we still find well defined peaks in the
calculated NMR spectra corresponding to the $S=1/2$ chain end excitations. At
low temperatures, inter chain couplings could be important, resulting in a more
complicated phase.

</DOC>
<DOC>
<DOCNO> 70284 </DOCNO>
Bethe-Salpeter Approach for the $P_{33}$ Elastic Pion-Nucleon Scattering


  Heavy Baryon Chiral Perturbation Theory (HBChPT) to leading order provides a
kernel to solve the Bethe-Salpeter equation for the $P_{33}$
($\Delta(1232)$-channel) $\pi-N$ system, in the infinite nucleon mass limit.
Crossed Born terms include, when iterated within the Bethe-Salpeter equation,
both {\it all} one- and {\it some} two-pion intermediate states, hence
preserving elastic unitarity below the two-pion production threshold. This
suggests searching for a solution with the help of dispersion relations and
suitable subtraction constants, when all in-elasticities are explicitly
neglected. The solution allows for a successful description of the experimental
phase shift from threshold up to $\sqrt{s}=1500$ MeV in terms of four
subtraction constants. Next-to-leading order HBChPT calculations are also used
to estimate the unknown subtraction constants which appear in the solution.
Large discrepancies are encountered which can be traced to the slow convergence
rate of HBChPT.

</DOC>
<DOC>
<DOCNO> 12053 </DOCNO>
Anisotropic Magnetoconductance in Quench-Condensed Ultrathin Beryllium


  Near the superconductor-insulator (S-I) transition, quench-condensed
ultrathin Be films show a large magnetoconductance which is highly anisotropic
in the direction of the applied field. Film conductance can drop as much as
seven orders of magnitude in a weak perpendicular field (< 1 T), but is
insensitive to a parallel field in the same field range. We believe that this
negative magnetoconductance is due to the field de-phasing of the
superconducting pair wavefunction. This idea enables us to extract the finite
superconducting phase coherence length in nearly superconducting films. Our
data indicate that this local phase coherence persists even in highly
insulating films in the vicinity of the S-I transition.

</DOC>
<DOC>
<DOCNO> 13839 </DOCNO>
Loss of the magnetism in FeS


  It is argued that the formation of the non-magnetic state of FeS in external
pressures above 6.5 GPa is in agreement with the prediction of the quantum
atomistic solid-state theory, an extension of the crystal-field theory with the
spin-orbit coupling incorporated, and is related with the change of sign of the
off-cubic trigonal distortion marked by the change of the c/a ratio from >1.63
(magnetic) to <1.63 (non-magnetic). Keywords: highly-correlated electron
system, crystal field, low-spin state, Fe2+ ion, spin-orbit coupling

</DOC>
<DOC>
<DOCNO> 119621 </DOCNO>
Mass function of dark matter halos


  We combine data from a number of N-body simulations to predict the abundance
of dark halos in Cold Dark Matter universes over more than 4 orders of
magnitude in mass. A comparison of different simulations suggests that the
dominant uncertainty in our results is systematic and is smaller than 10--30%
at all masses, depending on the halo definition used. In particular, our
``Hubble Volume'' simulations of \tcdm and \lcdm cosmologies allow the
abundance of massive clusters to be predicted with uncertainties well below
those expected in all currently planned observational surveys. We show that for
a range of CDM cosmologies and for a suitable halo definition, the simulated
mass function is almost independent of epoch, of cosmological parameters, and
of initial power spectrum when expressed in appropriate variables. This
universality is of exactly the kind predicted by the familiar Press-Schechter
model, although this model predicts a mass function shape which differs from
our numerical results, overestimating the abundance of ``typical'' halos and
underestimating that of massive systems.

</DOC>
<DOC>
<DOCNO> 120892 </DOCNO>
Complex molecular gas structure in the Medusa merger


  High resolution OVRO aperture synthesis maps of the 12CO 1-0 emission in the
`Medusa' galaxy merger (NGC4194) reveal the molecular emission being
surprisingly extended. It is distributed on a total scale of 25$''$ (4.7 kpc) -
despite the apparent advanced stage of the merger. The complex, striking CO
morphology occupies mainly the center and the north-eastern part of the main
optical body. The extended 12CO flux is tracing two prominent dust lanes: one
which is crossing the central region at right angle and a second which curves
to the north-east and then into the beginning of the northern tidal tail. The
bulk of the 12CO emission (67%) can be found in a complex starburst region
encompassing the central 2kpc. The molecular gas is distributed in five major
emission regions of typical size 300pc. About 15% of the total 12CO flux is
found in a bright region 1.5'' south of the radio continuum nucleus. We suggest
that this region together with the kpc sized central starburst is being fueled
by gas flows along the central dust lane. We discuss the merger history of
NGC4194 and suggest that it may be the result of an early-type/spiral merger
with a shell emerging to the south of the center. The total molecular mass in
the system is estimated to be at most 2 X 10^9 M_sun (depending on the CO - H_2
conversion factor). The high 12CO/13CO 1-0 intensity ratio, ~20, indicates
highly excited physical conditions in the interstellar medium showing that the
starburst has a big impact on its surrounding ISM. At the current rate of star
formation, the gas will be consumed within 40 million years.

</DOC>
<DOC>
<DOCNO> 151899 </DOCNO>
Noncommutative Gauge Dynamics from Brane Configurations with Background


  We study D=3 field theories on the D3-branes stretched between two NS5-branes
with NS B-field background. The theory is a noncommutative gauge theory. The
mirror symmetry and S-duality of the theory are discussed. A new feature is
that the mirror of the noncommutative gauge theory is not a field theory but an
open string decoupled from the closed string. We also consider brane creation
phenomena and use the result to discuss the analogue of the Seiberg duality. A
noncommutative soliton is interpreted as a D1-brane induced on D3-brane.

</DOC>
<DOC>
<DOCNO> 71923 </DOCNO>
Cold Dark Matter detection in SUSY models at large tan(beta)


  We study the direct detection rate for SUSY cold dark matter (CDM) predicted
by the minimal supersymmetric standard model with universal boundary conditions
and large values for tan(beta). The relic abundance of the lightest
supersymmetric particle (LSP), assumed to be approximately a bino, is obtained
by including its coannihilations with the next-to-lightest supersymmetric
particle (NLSP), which is the lightest s-tau. The cosmological constraint on
this quantity severely limits the allowed SUSY parameter space, especially in
the case the CP-even Higgs has mass of around 114 GeV. We find that for large
tan(beta) it is possible to find a subsection of the allowed parameter space,
which yields detectable rates in the currently planned experiments.

</DOC>
<DOC>
<DOCNO> 14158 </DOCNO>
The waiting-time distribution of LIFFE bond futures


  We apply the Continuous Time Random Walk (CTRW) framework, introduced in
finance by Scalas et al., to the analysis of the probability distribution of
time intervals between two consecutive trades in the case of BTP futures prices
traded at LIFFE in 1997. Results corroborate the validity of the CTRW approach
for the description of the temporal evolution of financial time series.

</DOC>
<DOC>
<DOCNO> 118314 </DOCNO>
Projected bispectrum in spherical harmonics and its application to


  We present a theoretical and exact analysis of the bispectrum of projected
galaxy catalogues. The result can be generalized to evaluate the projection in
spherical harmonics of any 3D bispectrum and therefore has applications to
cosmic microwave background and gravitational lensing studies. By expanding the
2D distribution of galaxies on the sky in spherical harmonics, we show how the
3-point function of the coefficients can be used in principle to determine the
bias parameter of the galaxy sample. If this can be achieved, it would allow a
lifting of the degeneracy between the bias and the matter density parameter of
the Universe which occurs in linear analysis of 3D galaxy catalogues. In
previous papers we have shown how a similar analysis can be done in three
dimensions, and we show here, through an error analysis and by implementing the
method on a simulated projected catalogue, that ongoing three-dimensional
galaxy redshift surveys (even with all the additional uncertainties introduced
by partial sky coverage, redshift-space distortions and smaller numbers) will
do far better than all-sky projected catalogues with similar selection
function.

</DOC>
<DOC>
<DOCNO> 71275 </DOCNO>
Non-perturbative dynamics of hot non-Abelian gauge fields


  The dynamics of high temperature gauge fields, on scales relevant for
non-perturbative phenomena such as electroweak baryogenesis, may be described
by a remarkably simple effective theory. This theory, which takes the form of a
local, stochastic, classical Yang-Mills theory, depends on a single parameter,
the non-Abelian (or ``color'') conductivity. This effective theory has recently
been shown to be valid to next-to-leading-log order (NLLO), provided one uses
an improved NLLO value for the non-Abelian conductivity. Comparisons of
numerical simulations using this NLLO effective theory and a more microscopic
effective theory agree surprisingly well.

</DOC>
<DOC>
<DOCNO> 119651 </DOCNO>
Statistical characteristics of simulated walls


  The large scale matter distribution in three different simulations of CDM
models is investigated and compared with corresponding results of the
Zel'dovich theory of nonlinear gravitational instability. We show that the
basic characteristics of wall-like structure elements are well described by
this theory, and that they can be expressed by the cosmological parameters and
a few spectral moments of the perturbation spectrum. Therefore the
characteristics of such elements provide reasonable estimates of these
parameters. We show that the compressed matter is relaxed and gravitationally
confined, what manifests itself in the existence of walls as (quasi)stationary
structure elements with life time restricted by their disruption into high
density clouds.
  The matter distribution is investigated both in the real and redshift spaces.
In both cases almost the same particles form the walls, and we estimate
differences in corresponding wall characteristics. The same methods are applied
to several mock catalogues of 'galaxies' what allows us to characterize a large
scale bias between the spatial distribution of dark matter and of simulated
`galaxies'.

</DOC>
<DOC>
<DOCNO> 102085 </DOCNO>
The non-Archimedean analogs of the Bochner-Kolmogorov, Minlos-Sazonov


  Measures on a non-Archimedean Banach space $X$ are considered with values in
the real field $\bf R$ and in the non- Archimedean fields. The non-Archimedean
analogs of the Bochner- Kolmogorov and Minlos-Sazonov theorems are given.
Moreover, infinite products of measures are studied and the analog of the
Kakutani theorem is investigated.

</DOC>
<DOC>
<DOCNO> 150635 </DOCNO>
A note on consistent anomalies in noncommutative YM theories


  Via descent equations we derive formulas for consistent gauge anomalies in
noncommutative Yang-Mills theories.

</DOC>
<DOC>
<DOCNO> 9938 </DOCNO>
Quantum Pumping in the Magnetic Field: Role of Discrete Symmetries


  We consider an effect of the discrete spatial symmetries and magnetic field
on the adiabatic charge pumping in mesoscopic systems. In general case, there
is no symmetry of the pumped charge with respect to the inversion of magnetic
field Q(B) \neq Q(-B). We find that the reflection symmetries give rise to
relations Q(B)=Q(-B) or Q(B)=-Q(-B) depending on the orientation of the
reflection axis. In presence of the center of inversion, Q(B) = 0. Additional
symmetries may arise in the case of bilinear pumping.

</DOC>
<DOC>
<DOCNO> 122281 </DOCNO>
Evolutionary Constraints from Infra-Red Source Counts


  The backward evolution approach to modelling galaxy source counts is
re-visited in the wake of the numerous results and revelations from the
Infrared Space Observatory (ISO), the Submillimetre Common User Bolometer Array
(SCUBA) and the detections and measurements of the cosmic extragalactic
background light. Using the framework of the Pearson and Rowan-Robinson (1996)
galaxy evolution model, the observed source counts and background measurements
are used to constrain the evolution in the galaxy population. It is found that
a strong evolution in both density and luminosity of the high luminosity tail
of the IR luminosity function, interpreted as the ultraluminous galaxies
discovered first by IRAS and later elevated in status by SCUBA and ISO, can
account for the source counts from 15um (where it matches the undulation in the
integral counts and hump in the differential counts extremely well), to the
sub-mm region, as well as explain the peak in the cosmic infrared background at
140um. The sub-mm counts are interpreted as the superposition of 2 separate
populations comprising of ULIGs at the brighter sub-mm fluxes and starburst
galaxies at fluxes fainter than 2mJy. In this scenario the high redshift ULIGs
are tenuously interpreted as the progenitors of today's giant elliptical
galaxies.

</DOC>
<DOC>
<DOCNO> 119145 </DOCNO>
Radio supernovae, supernova remnants and HII regions in NGC 2146


  We present a high-resolution 5-GHz radio continuum map of the starburst
galaxy NGC 2146 made with MERLIN and the VLA, in a search of radio supernovae
and supernova remnants expected to be already produced by the most massive
stars in the starburst. At 5 GHz, about 20 point sources were detected earlier
by Glendenning & Kronberg (1986) in the central 800 pc of NGC 2146. Our
observations with higher sensitivity and resolution made with MERLIN and the
VLA confirms the detection of 18 sources, and resolves 7 of them. Additional
1.6-GHz MERLIN observations disclose 9 sources coincident in position with
those detected at 5 GHz, which allows us to derive their spectral indices. Only
3 sources have indices consistent with synchrotron emission from supernova
remnants or radio supernovae, while the others have very steep inverted
spectra. We suggest that the sources with positive spectral index are optically
thick ultra-compact and/or ultra-dense HII regions with high electron densities
and high emission measures (EM > 10^(7) cm^(-6) pc). Minimum energy
requirements indicate that these regions may contain up to 1000 equivalent
stars of type O6. When compared with M 82, the galaxy NGC 2146 lacks however a
large number of supernova remnants. We suggest that NGC 2146 is experiencing a
burst of star formation stronger than that in M 82, but being in a younger
phase. We may, however, not exclude an alternative scenario in which strong
free-free absorption at 1.6 GHz in foreground ionized gas with very high
emission measures (EM > 10^(8) cm^(-6) pc) hides a certain number of supernova
remnants, thus rendering for some sources the observed inverted spectra.

</DOC>
<DOC>
<DOCNO> 119977 </DOCNO>
The Very Low Mass Component of the Gliese 105 System


  Multiple-epoch, multicolor images of the astrometric binary Gliese 105A and
its very low mass companion Gliese 105C have been obtained using the Hubble
Space Telescope's Wide Field Planetary Camera 2 (WFPC2) and Near-Infrared
Camera and Multi-Object Spectrometer (NICMOS). The optical and near-infrared
colors of Gl 105C strongly suggest a spectral type of M7V for that star.
Relative astrometric measurements spanning 3 yr reveal the first evidence of Gl
105C's orbital motion. Previous long-term astrometric studies at Sproul and
McCormick Observatories have shown that the period of Gl 105A's perturbation is
approximately 60 yr. To satisfy both the observed orbital motion and Gl 105A's
astrometric period, Gl 105C's orbit must have an eccentricity of approximately
0.75 and a semimajor axis of approximately 15 AU. Measurements of Gl 105A's
radial velocity over 12 yr show a linear trend with a slope of 11.3 m/s/yr,
which is consistent with these orbital constraints and a nearly face-on orbit.
As no other faint companions to Gl 105A have been detected, we conclude that Gl
105C is probably the source of the 60-yr astrometric perturbation.

</DOC>
<DOC>
<DOCNO> 71549 </DOCNO>
CMB anisotropies in pre-big bang cosmology


  We present an alternative scenario for cosmic structure formation where
initial fluctuations are due to Kalb-Ramond axions produced during a pre-big
bang phase of inflation. We investigate whether this scenario, where the
fluctuations are induced by seeds and therefore are of isocurvature nature, can
be brought in agreement with present observations by a suitable choice of
cosmological parameters. We also discuss several observational signatures which
can distinguish axion seeds from standard inflationary models.

</DOC>
<DOC>
<DOCNO> 99975 </DOCNO>
The automorphism tower problem revisited


  It is well-known that the automorphism towers of infinite centreless groups
of cardinality kappa terminate in less than (2^{kappa})^+ steps. But an easy
counting argument shows that (2^{kappa})^+ is not the best possible bound.
However, in this paper, we will show that it is impossible to find an explicit
better bound using ZFC.

</DOC>
<DOC>
<DOCNO> 9236 </DOCNO>
The crumpling transition of membranes driven by quantum fluctuations in


  We consider a D-dimensional fluid membrane in a D+1-dimensional embedding
space, subject to quantum fluctuations. The corresponding action is invariant
under coordinate transformations and depends only on the shape of the membrane
and its variation, neglecting tangential degrees of freedom. We calculate the
resulting field theory to one loop order in a D=epsilon expansion and find a
quantum transition even at T=0.

</DOC>
<DOC>
<DOCNO> 83169 </DOCNO>
On the theory of system administration


  This paper describes necessary elements for constructing theoretical models
of network and system administration. Armed with a theoretical model it becomes
possible to determine best practices and optimal strategies in a way which
objectively relates policies and assumptions to results obtained. It is
concluded that a mixture of automation and human, or other intelligent
incursion is required to fully implement system policy with current technology.
Some aspects of the author's immunity model for automated system administration
are explained, as an example. A theoretical framework makes the prediction that
the optimal balance between resource availability and garbage collection
strategies is encompassed by the immunity model.

</DOC>
<DOC>
<DOCNO> 8595 </DOCNO>
Boundary states for a free boson defined on finite geometries


  Langlands recently constructed a map that factorizes the partition function
of a free boson on a cylinder with boundary condition given by two arbitrary
functions in the form of a scalar product of boundary states. We rewrite these
boundary states in a compact form, getting rid of technical assumptions
necessary in his construction. This simpler form allows us to show explicitly
that the map between boundary conditions and states commutes with conformal
transformations preserving the boundary and the reality condition on the scalar
field.

</DOC>
<DOC>
<DOCNO> 40401 </DOCNO>
What Will We Learn If a Higgs Boson is Found?


  We examine what can be deduced from the discovery of a Higgs boson, focusing
on a possible discovery at LEP. The analysis begins with the most general
situation where no further constraints can be deduced, and then specializes to
include various assumptions. Assuming naturalness, the relatively large mass
suggests that one or more of larger $\tan \beta$, large phase, or extra
singlets is present. We discuss the implications of a Higgs mass discovery for
the SUSY spectrum, and in particular gluinos and stops. We show that a lighter
gluino produceable at the Tevatron remains a likely possibility, in
disagreement with a recent claim.

</DOC>
<DOC>
<DOCNO> 101831 </DOCNO>
The Multiplicative Inverse Eigenvalue Problem over an Algebraically


  Let $M$ be a square matrix and let $p(t)$ be a monic polynomial of degree
$n$. Let $Z$ be a set of $n\times n$ matrices. The multiplicative inverse
eigenvalue problem asks for the construction of a matrix in $Z$ such that the
product matrix $MZ$ has characteristic polynomial $p(t)$. In this paper we
provide new necessary and sufficient conditions when $Z$ is an affine variety
over an algebraically closed field.

</DOC>
<DOC>
<DOCNO> 118711 </DOCNO>
The observation of Delta Sct and Gamma Dor stars by using MONS satellite


  The MONS space experiment will be able to verify some of the most important
topics in the asteroseismologic studies of Delta Sct and Gamma Dor stars. We
discuss how the $\gamma$ Doradus can be considered possible "bridges" between
the opacity driven overstable pulsation and the stochastically excited solar
like oscillation. For this reason the possible inclusion of a Gamma Dor
representative in the MONS main target list is presented and discussed. To
study Delta Sct stars, an appropriate frequency resolution, comparable to or
better than what is currently achieved by ground-based observations, is
necessary and hence two runs are recommended. To avoid over-scheduling of the
Main Camera, a possible combination of observations from the Main Camera and
from the Star Trackers is proposed. As a result, key-objects could be
adequately monitored, affording the possibility to enter into details of
amplitude variations. Simultaneously, the same results could be obtained on two
Gamma Dor stars.

</DOC>
<DOC>
<DOCNO> 121522 </DOCNO>
Do High-Velocity Clouds Really Fuel Galactic Star Formation?


  Tantalizing evidence has been presented supporting the suggestion that a
large population of extragalactic gas clouds permeates the Local Group, a
population which has been associated with the Galactic High-Velocity Clouds
(HVCs). We comment on both the strengths and weaknesses of this suggestion,
informally referred to as the Blitz/Spergel picture. Theoretical predictions
for the spatial and kinematic distributions, metallicities, distances, and
emission properties of Blitz/Spergel HVCs will be confronted with extant
observational data.

</DOC>
<DOC>
<DOCNO> 117126 </DOCNO>
Comment on Mie Scattering from a Sonoluminescing Bubble with High


  A key parameter underlying the existence of sonoluminescence (SL)is the time
relative to SL at which acoustic energy is radiated from the collapsed bubble.
Light scattering is one route to this quantity. We disagree with the statement
of Gompf and Pecha that -highly compressed water causes the minimum in
scattered light to occur 700ps before SL- and that this effect leads to an
overestimate of the bubble wall velocity. We discuss potential artifacts in
their experimental arrangement and correct their description of previous
experiments on Mie scattering.

</DOC>
<DOC>
<DOCNO> 99888 </DOCNO>
Introduction to the Alexandru Conjecture


  Is a Verma module transformed into another Verma module by a selfequivalence?
The answer is affirmative and the proof suggests a notion of standard object in
the category of Harish-Chandra modules that coincides often, but not always,
with the usual one.

</DOC>
<DOC>
<DOCNO> 11832 </DOCNO>
Fractal statistics, fractal index and fractons


  The concept of fractal index is introduced in connection with the idea of
universal class $h$ of particles or quasiparticles, termed fractons, which obey
fractal statistics. We show the relation between fractons and conformal field
theory(CFT)-quasiparticles taking into account the central charge $c[\nu]$ and
the particle-hole duality $\nu\longleftrightarrow\frac{1}{\nu}$, for
integer-value $\nu$ of the statistical parameter. The Hausdorff dimension $h$
which labelled the universal classes of particles and the conformal anomaly are
therefore related. We also establish a connection between Rogers dilogarithm
function, Farey series of rational numbers and the Hausdorff dimension.

</DOC>
<DOC>
<DOCNO> 152167 </DOCNO>
Second-Order Radiative Corrections to the Axial Vector Anomaly


  We re-examine the historically important decay of the neutral pion into two
photons. Schwinger's Equivalence Theorem is confirmed. We then consider
radiative corrections to the famous Adler-Bell-Jackiw (ABJ) anomaly. The result
depends crucially on a physically motivated regularization scheme. Our approach
is largely based on Schwinger's source (dispersion) method.

</DOC>
<DOC>
<DOCNO> 11690 </DOCNO>
Population Monte Carlo algorithms


  We give a cross-disciplinary survey on ``population'' Monte Carlo algorithms.
In these algorithms, a set of ``walkers'' or ``particles'' is used as a
representation of a high-dimensional vector. The computation is carried out by
a random walk and split/deletion of these objects. The algorithms are developed
in various fields in physics and statistical sciences and called by lots of
different terms -- ``quantum Monte Carlo'', ``transfer-matrix Monte Carlo'',
``Monte Carlo filter (particle filter)'',``sequential Monte Carlo'' and
``PERM'' etc. Here we discuss them in a coherent framework. We also touch on
related algorithms -- genetic algorithms and annealed importance sampling.
  # Sorry that the previous update was incomplete by a technical reason.
    This is the correct revised version.

</DOC>
<DOC>
<DOCNO> 122311 </DOCNO>
The solar tachocline and its variation (?)


  The solar tachocline, located at the interface between the latitude-dependent
rotation of the convection zone and the rigid radiative interior, presents high
gradients of angular velocity which are of particular interest for the models
of the solar dynamo and angular momentum transport. Furthermore, latitudinal
and temporal variations of the tachocline parameters, if any, are also of
particular interest in order to constrain models. We present a review of some
of the theories of the tachocline and their predictions that may be tested by
helioseismology. We describethe methods for inferring the tachocline parameters
from observations and the associated difficulties. A review of results
previously obtained is given and an analysis of the new 6 years database of
LOWL observations is presented which yields no compelling evidence of
variations or general trend of the tachocline parameters during the ascending
phase of the current solar cycle (1994-2000).

</DOC>
<DOC>
<DOCNO> 13646 </DOCNO>
What can we learn from comparison between cuprates and He films ? :


  In the underdoped, overdoped, Zn-doped or stripe-forming regions of
high-$T_{c}$ cuprate superconductors (HTSC), the superfluid density
$n_{s}/m^{*}$ at $T\to 0$ shows universal correlations with $T_{c}$. Similar
strong correlations exist between 2-dimensional superfluid density and
superfluid transition temperature in thin films of $^{4}$He in non-porous or
porous media, and $^{4}$He/$^{3}$He film adsorbed on porous media. Based on
analogy between HTSC and He film systems, we propose a model for cuprates
where: (1) the overdoped region is characterized by a phase separation similar
to $^{4}$He/$^{3}$He; and (2) pair (boson) formation and fluctuating
superconductivity occur at separate temperatures above $T_{c}$ in the
underdoped region.

</DOC>
<DOC>
<DOCNO> 169729 </DOCNO>
Operational criterion and constructive checks for the separability of


  We consider low rank density operators $\varrho$ supported on a $M\times N$
Hilbert space for arbitrary $M$ and $N$ ($M\leq N$) and with a positive partial
transpose (PPT) $\varrho^{T_A}\ge 0$. For rank $r(\varrho) \leq N$ we prove
that having a PPT is necessary and sufficient for $\varrho$ to be separable; in
this case we also provide its minimal decomposition in terms of pure product
states. It follows from this result that there is no rank 3 bound entangled
states having a PPT. We also present a necessary and sufficient condition for
the separability of generic density matrices for which the sum of the ranks of
$\varrho$ and $\varrho^{T_A}$ satisfies $r(\varrho)+r(\varrho^{T_A}) \le
2MN-M-N+2$. This separability condition has the form of a constructive check,
providing thus also a pure product state decomposition for separable states,
and it works in those cases where a system of couple polynomial equations has a
finite number of solutions, as expected in most cases.

</DOC>
<DOC>
<DOCNO> 100715 </DOCNO>
The mystery of the brane relation


  The purpose of the present paper is to introduce and explore two surprises
that arise when we apply a standard procedure to study the number of finite
type invariants of 3-manifolds introduced independently by M. Goussarov and K.
Habiro based on surgery on claspers, Y-graphs or clovers, \cite{Gu,Ha,GGP}. One
surprise is that the upper bounds depend on a bit more than a choice of
generators for H_1. A complementary surprise a curious brane relation (in two
flavors, open and closed) which shows that the upper bounds are in a certain
sense independent of the choice of generators of H_1.

</DOC>
<DOC>
<DOCNO> 67911 </DOCNO>
Flavor Structure and Supersymmetric CP-Violation


  In this talk, we address the possibility of finding supersymmetry through
indirect searches in the K and B systems. We prove that, in the absence of the
Cabibbo-Kobayashi-Maskawa phase, a general Minimal Supersymmetric Standard
Model with all possible phases in the soft-breaking terms, but no new flavor
structure beyond the usual Yukawa matrices, can never give a sizeable
contribution to $\epsilon_K$, $\epsilon^\prime/\epsilon$ or hadronic B^0 CP
asymmetries. However, Minimal Supersymmetric models with additional flavor
structures in the soft-supersymmetry breaking terms can produce large
deviations from the Standard Model predictions. Hence, observation of
supersymmetric contributions to CP asymmetries in B decays would be the first
sign of the existence of new flavor structures in the soft-terms and would hint
at a non-flavor blind mechanism of supersymmetry breaking.

</DOC>
<DOC>
<DOCNO> 150780 </DOCNO>
Anomalous U(1) gauge symmetries and heterotic-typeI/II string duality


  Anomalous U(1) gauge symmetries can appear both in heterotic and type I
string theories. In the heterotic case we find a single anomalous U(1), while
in open string theories several such symmetries can appear. Nonetheless, there
is a conjectured duality symmetry that might connect these two theories. We
review the properties of anomalous gauge symmetries in various string theories
as well as the status of this heterotic-type I/II duality. We also comment on
the possible phenomenological applications of anomalous gauge symmetries in
string theory.

</DOC>
<DOC>
<DOCNO> 12526 </DOCNO>
Screening Breakdown on the Route toward the Metal-Insulator Transition


  Exploiting the spin resonance of two-dimensional (2D) electrons in SiGe/Si
quantum wells we determine the carrier-density-dependence of the magnetic
susceptibility. Assuming weak interaction we evaluate the density of states at
the Fermi level D(E_F), and the screening wave vector, q_TF. Both are constant
at higher carrier densities n, as for an ideal 2D carrier gas. For n < 3e11
cm-2, they decrease and extrapolate to zero at n = 7e10 cm-2. Calculating the
mobility from q_TF yields good agreement with experimental values justifying
the approach. The decrease in D(E_F) is explained by potential fluctuations
which lead to tail states that make screening less efficient and - in a
positive feedback - cause an increase of the potential fluctuations. Even in
our high mobility samples the fluctuations exceed the electron-electron
interaction leading to the formation of puddles of mobile carriers with at
least 1 micrometer diameter.

</DOC>
<DOC>
<DOCNO> 13911 </DOCNO>
Nonasymptotic critical behavior from field theory


  The obtention (up to five or six loop orders) of nonasymptotic critical
behavior, above and below Tc, from the field theoretical framework is presented
and discussed.

</DOC>
<DOC>
<DOCNO> 152243 </DOCNO>
Large N Structure of the IIB Matrix Model


  We study large N behavior of the IIB matrix model using the equivalence
between the IIB matrix model for finite N and a field theory on a
non-commutative periodic lattice with N x N sites. We find that the large N
dependences of correlation functions can be obtained by naively counting the
number of fields in the field theory on the non-commutative periodic lattice.
Furthermore the large N scaling behavior of the coupling constant g is
determined if we impose that the expectation values of Wilson loops are
calculable.

</DOC>
<DOC>
<DOCNO> 122101 </DOCNO>
The unique rapid variabilities of the iron K$\alpha$ line profiles in


  We present a detailed analysis of the iron K$\alpha$ line variabilities in
NGC 4151 by using long ASCA observation data obtained in May 1995. Despite the
relatively small amplitude variations in the continuum flux, the iron K$\alpha$
line flux and profile show dramatic variations. Particularly, the line profile
changes from single peak to seeming double peaks and back in time scales of a
few 10$^4$ sec. The seemingly double-peaked profiles can be well interpreted as
line emission from a Keplerian ring around a massive black hole. An absorption
line at around 5.9 keV is also marginnaly detected. We discussed current Fe K
line models, but none of them can well explain the observed line and continuum
variations.

</DOC>
<DOC>
<DOCNO> 72326 </DOCNO>
Nonlinear QED Effects in Heavy Ion Collisions


  Peripheral collisions of relativistic heavy ions uniquely probe many aspects
of QED. Examples include $e^+e^-$ pair production and nuclear excitation in
strong fields. After discussing these reactions, I will draw parallels between
$\gamma\to e^+e^-$ and $\gamma\to q\bar q$ and consider partly hadronic
reactions. The scattered $q\bar q$ pairs are a prolific source of vector
mesons, which demonstrate many quantum effects. The two ions are a two-source
interferometer, demonstrating interference between meson waves. Multiple vector
meson production will demonstrate superradiance, a first step toward a vector
meson laser. Finally, I will discuss the experimental program planned at the
RHIC and LHC heavy ion colliders.

</DOC>
<DOC>
<DOCNO> 178953 </DOCNO>
Baryon-Rich Quark-Gluon Plasma in Nuclear Collision


  The maximum achievable temperature (energy density) and minimum kinetic
energy required for the formation of a baryon-rich quark-gluon plasma formed at
central rapidity in small impact parameter nuclear collisions is estimated. A
possible mechanism leading to the pile-up of matter is introduced. Plasma
formation is expected to appear at about 15 GeV/Nucleon uranium beam energy on
a stationary target or 2.7 GeV/Nucleon in colliding beams.

</DOC>
<DOC>
<DOCNO> 8917 </DOCNO>
Interaction effects on the conductance peak height statistics in quantum


  A random interaction matrix model is used to study the statistics of
conductance peak heights in Coulomb blockade quantum dots. When the
single-particle dynamics conserves time-reversal symmetry, the peak height
statistics is insensitive to the interaction strength. But when the
single-particle dynamics breaks time-reversal symmetry, the peak height
statistics exhibits a crossover from unitary to orthogonal symmetry as the
interaction strength increases. This crossover is driven by the time-reversal
symmetry of the interaction. Our random interaction matrix model describes
features of both the measured peak height and peak spacing statistics.

</DOC>
<DOC>
<DOCNO> 170422 </DOCNO>
Local-field corrections to the decay rate of excited molecules in


  The decay rate and the classical radiation power of an excited molecule
(atom) located in the center of a dispersive and absorbing dielectric sphere
taken as a simple model of a cavity are calculated adopting the Onsager model
for the local field. The local-field correction factor to the external
(radiation and absorption) power loss of the molecule is found to be
$|3\epsilon(\omega)/[3\epsilon(\omega)+1]|^2$, with $\epsilon(\omega)$ being
the dielectric function of the sphere. However, local-field corrections to the
total decay rate (power loss) of the molecule are found to be much more
complex, including those to the decay rate in the infinite cavity medium, as
derived very recently by Scheel et al. [Rev. A 60, 4094 (1999)], and similiar
corrections to the cavity-induced decay rate. The results obtained can be cast
into model-independent forms. This suggests the general results for the
local-field corrections to the decay rate and to the external power loss of a
molecule in an absorbing cavity valid for molecule positions away from the
cavity walls.

</DOC>
<DOC>
<DOCNO> 152370 </DOCNO>
Integrable hierarchies from BRST-anti-BRST gauge-fixing


  The BRST formulation is used in order to derive the existence criterion for
classical bi-Hamiltonian systems, based on non-anomalous deformation of the
gauge-fixing structure. The recursion operator is then used to provide the
entire hierarchy of integrable models associated to the original BRST and
anti-BRST charges.

</DOC>
<DOC>
<DOCNO> 151233 </DOCNO>
Quantization of the Relativistic Particle


  We revise the problem of the quantization of relativistic particle,
presenting a modified consistent canonical scheme, which allows one not only to
include arbitrary backgrounds in the consideration but to get in course of the
quantization a consistent relativistic quantum mechanics, which reproduces
literally the behavior of the one-particle sector of the corresponding quantum
field. At the same time this construction presents a possible solution of the
well-known old problem how to construct a consistent quantum mechanics on the
base of a relativistic wave equation.

</DOC>
<DOC>
<DOCNO> 150494 </DOCNO>
Induced Variational Method from Supersymmetric Quantum Mechanics and the


  The formalism of Supersymmetric Quantum Mechanics supplies a trial wave
function to be used in the Variational Method. The screened Coulomb potential
is analysed within this approach. Numerical and exact results for energy
eigenvalues are compared.

</DOC>
<DOC>
<DOCNO> 152165 </DOCNO>
Vacuum Nodes and Anomalies in Quantum Theories


  We show that nodal points of ground states of some quantum systems with
magnetic interactions can be identified in simple geometric terms. We analyse
in detail two different archetypical systems: i) a planar rotor with a
non-trivial magnetic flux $\Phi$, ii) Hall effect on a torus. In the case of
the planar rotor we show that the level repulsion generated by any reflection
invariant potential $V$ is encoded in the nodal structure of the unique vacuum
for $\theta=\pi$. In the second case we prove that the nodes of the first
Landau level for unit magnetic charge appear at the crossing of the two
non-contractible circles $\alpha_-$, $\beta_-$ with holonomies
$h_{\alpha_-}(A)= h_{\beta_-}(A)=-1$ for any reflection invariant potential
$V$. This property illustrates the geometric origin of the quantum translation
anomaly.

</DOC>
<DOC>
<DOCNO> 8631 </DOCNO>
Vibrational States of Glassy and Crystalline Orthotherphenyl


  Low-frequency vibrations of glassy and crystalline orthoterphenyl are studied
by means of neutron scattering. Phonon dispersions are measured along the main
axes of a single crystal, and the corresponding longitudinal and transversal
sound velocities are obtained. For glassy and polycrystalline samples, a
density of vibrational states is determined and cross-checked against other
dynamic observables. In the crystal, low-lying zone-boundary modes lead to an
excess over the Debye density of states. In the glass, the boson peak is
located at even lower frequencies. With increasing temperature, both glass and
crystal show anharmonicity.

</DOC>
<DOC>
<DOCNO> 119314 </DOCNO>
Two Ways of Biasing Galaxy Formation


  We calculate the galaxy bispectrum in both real and redshift space adopting
the most common prescriptions for local Eulerian biasing and Lagrangian
evolving-bias model. We show that the two biasing schemes make measurably
different predictions for these clustering statistics. The Eulerian
prescription implies that the galaxy distribution depends only on the
present-day local mass distribution, while its Lagrangian counterpart relates
the current galaxy distribution to the mass distribution at an earlier epoch
when galaxies first formed. Detailed measurement of the galaxy bispectrum (of
its reduced amplitude) can help establish whether galaxy positions are
determined by the current mass distribution or an earlier mass distribution.

</DOC>
<DOC>
<DOCNO> 9387 </DOCNO>
Dynamical response of a pinned two-dimensional Wigner crystal


  We re-examine a long-standing problem of a finite-frequency conductivity of a
weakly pinned two-dimensional classical Wigner crystal. In this system an
inhomogeneously broadened absorption line (pinning mode) centered at disorder
and magnetic field dependent frequency $\omega_p$ is known to appear. We show
that the relative linewidth $\Delta \omega_p / \omega_p$ of the pinning mode is
of the order of one in weak magnetic fields, exhibits a power-law decrease in
intermediate fields, and eventually saturates at a small value in strong
magnetic fields. The linewidth narrowing is due to a peculiar mechanism of
mixing between the stiffer longitudinal and the softer transverse components of
the collective excitations. The width of the high-field resonance proves to be
related to the density of states in the low-frequency tail of the zero-field
phonon spectrum. We find a qualitative agreement with recent experiments and
point out differences from the previous theoretical work on the subject.

</DOC>
<DOC>
<DOCNO> 99407 </DOCNO>
Topological obstructions to nonnegative curvature


  We find new obstructions to the existence of complete Riemannian metric of
nonnegative sectional curvature on manifolds with infinite fundamental groups.
In particular, we construct many examples of vector bundles whose total spaces
admit no nonnegatively curved metric.

</DOC>
<DOC>
<DOCNO> 70199 </DOCNO>
Bilinear R-parity Violation and Small Neutrino Masses: a Self-consistent


  We study extensions of supersymmetric models without R-parity which include
an anomalous U(1)_H horizontal symmetry. Bilinear R-parity violating terms
induce a neutrino mass at tree level of approximately $(\theta^2)^\delta$ eV
where $\theta\approx 0.22$ is the U(1)_H breaking parameter and $\delta$ is an
integer number that depends on the horizontal charges of the leptons. For
$\delta=1$ a unique self-consistent model arises in which i) all the
superpotential trilinear R-parity violating couplings are forbidden by
holomorphy; ii) the tree level neutrino mass falls in the range suggested by
the atmospheric neutrino problem; iii) radiative contributions to neutrino
masses are strongly suppressed resulting in a squared solar mass difference of
few 10^{-8} eV^2 which only allows for the LOW (or quasi-vacuum) solution to
the solar neutrino problem; iv) the neutrino mixing angles are not suppressed
by powers of $\theta$ and can naturally be large.

</DOC>
<DOC>
<DOCNO> 12868 </DOCNO>
Properties of few-electron artificial atoms


  The spectra of quantum dots of different geometry (``quantum ring'',
``quantum cylinder'', ``spherical square-well'' and ``parabolic confinement'')
are studied. The stochastic variational method on correlated Gaussian basis
functions and a large scale shell-model approach have been used to investigate
these ``artificial'' atoms and their properties in magnetic field. Accurate
numerical results are presented for $N$=2-8 electron systems.

</DOC>
<DOC>
<DOCNO> 85385 </DOCNO>
General Relativistic Modification of a Pulsar Electromagnetic Field


  We consider an exterior electromagnetic field surrounding a rotating star
endowed with a dipole magnetic field in the context of general relativity.
 The analytic solution for a stationary configuration is obtained, and the
general relativistic modifications and the implications for pulsar radiation
are investigated in detail. We find that the general relativistic corrections
of both the electric field strength and the curvature radii of magnetic field
lines tend to enhance the curvature radiation photon energy.

</DOC>
<DOC>
<DOCNO> 68132 </DOCNO>
Born-form approximation and full one-loop results for e^+e^- --> W^+W^-


  We review the results on representing the differential cross section for
W-pair produciton, including W decay and hard-photon bremsstrahlung, in terms
of a Born-form approximation of fairly simple analytic form. The result of the
Born-form approximation are compared with full-one-loop results. The emphasis
is on the energy range of future $e^+e^-$ (or $\mu^+\mu^-$) colliders.

</DOC>
<DOC>
<DOCNO> 9985 </DOCNO>
Superfluid weight vs. superconducting temperature based on a U(1)


  Based on an improved U(1) slave-boson approach to the t-J Hamiltonian, we
invest igate a relationship between the superfluid weight $n_s/m^*$(the
superconducting charge carrier density/the effective mass of the charge
carrier) and the superc onducting temperature $T_c$. From the present study we
find a linear increase of $n_s/m^*$ with $T_c$ with th e doping concentration
in the underdoped region, a saturation around the optimal doping and a decrease
in both $n_s/m^*$ and $T_c$ in the overdoped region. Such a trend of the
`boomerang' shaped locus in $n_s/m^*$ vs. $T_c$ with increas ing doping
concentration from the underdoped to the heavily overdoped region is predicted
to be in complete agreement with muon-spin-relaxation measurements. The
boomerang behavior is found to occur in correlation with reduction in the sp in
singlet pairing(spinon pairing) order in the heavily overdoped region.

</DOC>
<DOC>
<DOCNO> 84080 </DOCNO>
Second order perturbations of a Schwarzschild black hole: inclusion of


  We consider perturbations of a Schwarzschild black hole that can be of both
even and odd parity, keeping terms up to second order in perturbation theory,
for the $\ell=2$ axisymmetric case. We develop explicit formulae for the
evolution equations and radiated energies and waveforms using the
Regge-Wheeler-Zerilli approach. This formulation is useful, for instance, for
the treatment in the ``close limit approximation'' of the collision of
counterrotating black holes.

</DOC>
<DOC>
<DOCNO> 169841 </DOCNO>
Trapped ions in laser fields: A benchmark for deformed quantum


  Some properties of the non--linear coherent states (NCS), recognized by Vogel
and de Matos Filho as dark states of a trapped ion, are extended to NCS on a
circle, for which the Wigner functions are presented. These states are obtained
by applying a suitable displacement operator $D_{h}(\alpha) $ to the vacuum
state. The unity resolutions in terms of the projectors $| \alpha, h> < \alpha,
h^{-1}| ,| \alpha, h^{-1}> < \alpha, h| $ are presented together with a measure
allowing a resolution in terms of $| \alpha, h> < \alpha, h| $. $D_{h}(\alpha)
$ is also used for introducing the probability distribution funtion
$\rho_{A,h}(z) $ while the existence of a measure is exploited for extending
the P-representation to these states. The weight of the n-th Fock state of the
NCS relative to a trapped ion with Lamb-Dicke parameter $\eta ,$ oscillates so
wildly as $n$ grows up to infinity that the normalized NCS fill the open circle
$\eta ^{-1}$ in the complex $\alpha $-plane. In addition this prevents the
existence of a measure including normalizable states only. This difficulty is
overcome by introducing a family of deformations which are rational functions
of n, each of them admitting a measure. By increasing the degree of these
rational approximations the deformation of a trapped ion can be approximated
with any degree of accuracy and the formalism of the P-representation can be
applied.

</DOC>
<DOC>
<DOCNO> 169895 </DOCNO>
Two-mode Nonlinear Coherent States


  Two-mode nonlinear coherent states are introduced in this paper. The pair
coherent states and the two-mode Perelomov coherent states are special cases of
the two-mode nonlinear coherent states. The exponential form of the two-mode
nonlinear coherent states is given. The photon-added or photon-subtracted
two-mode nonlinear coherent states are found to be two-mode nonlinear coherent
states with different nonlinear functions. The parity coherent states are
introduced as examples of two-mode nonlinear coherent states, and they are
superpositions of two corresponding coherent states. We also discuss how to
generate the parity coherent states in the Kerr medium.

</DOC>
<DOC>
<DOCNO> 102366 </DOCNO>
Finite action solutions of SO(2,1) Hitchin's equations


  We present a 1-parameter family of finite action solutions to the $S0(2,1)$
Hitchin's equations and explore some of its basic properties. For a fixed value
of the parameter, the solution is smooth. We conclude by showing a
multi-particle generalization of our basic solutions.

</DOC>
<DOC>
<DOCNO> 170702 </DOCNO>
 Quantum dynamical theory for squeezing the output of a Bose-Einstein


  A linear quantum dynamical theory for squeezing the output of the trapped
Bose-Einstein condensate is presented with the Bogoliubov approximation. We
observe that the non-classical properties, such as sub-Poisson distribution and
quadrature squeezing effect, mutually oscillate between the quantum states of
the applied optical field and the resulting atom laser beam with time. In
particular, it is shown that an initially squeezed optical field will lead to
squeezing in the outcoupled atomic beam at later times.

</DOC>
<DOC>
<DOCNO> 13173 </DOCNO>
Analytical Results for Trapped Weakly Interacting Bosons in Two


  We consider a model of N two-dimensional bosons in a harmonic trap with
translational and rotational invariant, weak two-particle interaction. We
present in configuration space a systematical recursive method for constructing
all wave functions with angular momentum L and corresponding energies and apply
it to L\leq 6 for all N. The lower and the upper bounds for interaction energy
are estimated. We analitically confirm the conjecture of Smith et al. that
elementary symmetric polynomial is the ground state for repulsive delta
interaction, for all N\geq L up to L\leq 6. Additionally, we find that there
exist vanishing-energy solutions for L\geq N(N-1), signalizing the exclusive
statistics. Finally, we consider briefly the case of attractive power-like
potential r^k, k>-2, and prove that the lowest-energy state is still the one in
which all angular momentum is absorbed by the center-of-mass motion.

</DOC>
<DOC>
<DOCNO> 14044 </DOCNO>
Excess Modes in the Vibrational Spectrum of Disordered Systems and the


  We study a disordered vibrational model system, where the spring constants k
are chosen from a distribution P(k) ~ 1/k above a cut-off value k_min > 0. We
can motivate this distribution by the presence of free volume in glassy
materials. We show that the model system reproduces several important features
of the boson peak in real glasses: (i) a low-frequency excess contribution to
the Debye density of states, (ii) the hump of the specific heat c_V(T)
including the power-law relation between height and position of the hump, and
(iii) the transition to localized modes well above the boson peak frequency.

</DOC>
<DOC>
<DOCNO> 174563 </DOCNO>
Isospin influences on particle emission and critical phenomenon in


  Features of particle emission and critical point behavior are investigated as
functions of the isospin of disassembling sources and temperature at a moderate
freeze-out density for medium-size Xe isotopes in the framework of isospin
dependent lattice gas model. Multiplicities of emitted light particles,
isotopic and isobaric ratios of light particles show the strong dependence on
the isospin of the dissociation source, but double ratios of light isotope
pairs and the critical temperature determined by the extreme values of some
critical observables are insensitive to the isospin of the systems. Values of
the power law parameter of cluster mass distribution, mean multiplicity of
intermediate mass fragments ($IMF$), information entropy ($H$) and Campi's
second moment ($S_2$) also show a minor dependence on the isospin of Xe
isotopes at the critical point. In addition, the slopes of the average
multiplicites of the neutrons ($N_n$), protons ($N_p$), charged particles
($N_{CP}$), and IMFs ($N_{imf}$), slopes of the largest fragment mass number
($A_{max}$), and the excitation energy per nucleon of the disassembling source
($E^*/A$) to temperature are investigated as well as variances of the
distributions of $N_n$, $N_p$, $N_{CP}$, $N_{IMF}$, $A_{max}$ and $E^*/A$. It
is found that they can be taken as additional judgements to the critical
phenomena.

</DOC>
<DOC>
<DOCNO> 72265 </DOCNO>
Neutrino Masses and Lepton-Flavor Violation in Supersymmetric Models


  We analyze in detail lepton-flavor violation (LFV) in the charged-lepton
sector such as $\mu \to e \gamma$, $\tau \to \mu \gamma$, $\mu \to eee$ and the
$\mu \to e$ conversion in nuclei, within the framework of supersymmetric models
with lopsided Froggatt--Nielsen charges, in which the large mixing in the
neutrino sector as well as small mixings in the quark sector can be naturally
accommodated. We show that the present experimental limits on the LFV processes
already exclude some of the models. The future proposed search for LFV,
especially in muon processes, can provide a significant probe to this
framework. We also stress the importance of the measurement of $U^{MNS}_{e3}$
in neutrino experiments, and the fact that the KamLAND experiment could play a
significant role to test a certain class of models.

</DOC>
<DOC>
<DOCNO> 102662 </DOCNO>
A construction of symplectic connections through reduction


  We give an elementary construction of symplectic connections through
reduction. This provides an elegant description of a class of symmetric spaces
and gives examples of symplectic connections with Ricci type curvature, which
are not locally symmetric; the existence of such symplectic connections was
unknown.

</DOC>
<DOC>
<DOCNO> 68025 </DOCNO>
Gravitational waves in preheating


  We study the evolution of gravitational waves through the preheating era that
follows inflation. The oscillating inflaton drives parametric resonant growth
of scalar field fluctuations, and although super-Hubble tensor modes are not
strongly amplified, they do carry an imprint of preheating. This is clearly
seen in the Weyl tensor, which provides a covariant description of
gravitational waves.

</DOC>
<DOC>
<DOCNO> 69859 </DOCNO>
Enhanced J/Psi Production in Deconfined Quark Matter


  In high energy heavy ion collisions at the Relativistic Heavy Ion Collider
(RHIC) at Brookhaven and the Large Hadron Collider (LHC) at CERN, each central
event will contain multiple pairs of heavy quarks. if a region of deconfined
quarks and gluons is formed, a new mechanism for the formation of heavy
quarkonium bound states will be activated. This is a result of the mobility of
heavy quarks in the deconfined region, such that bound states can be formed
from a quark and an antiquark which were originally produced in separate
incoherent interactions. Model estimates of this effect for J/psi production at
RHIC indicate that significant enhancements are to be expected. Experimental
observation of such enhanced production would provide evidence for
deconfinement unlikely to be compatible with competing scenarios.

</DOC>
<DOC>
<DOCNO> 116331 </DOCNO>
Precision Measurement of the Lifetime of the 3d D_{5/2} state in 40Ca+


  We report a measurement of the lifetime of the 3d 2D_{5/2} metastable level
in 40Ca+, using quantum jumps of a single cold calcium ion in a linear Paul
trap. The 4s S_{1/2} - 3d D_{5/2} transition is significant for single-ion
optical frequency standards, astrophysical references, and tests of atomic
structure calculations. We obtain tau = 1.168 +- 0.007 s from observation of
nearly 64,000 quantum jumps during approximately 32 hours. Our result is more
precise and significantly larger than previous measurements. Experiments
carried out to quantity systematic effects included a study of a previously
unremarked source of systematic error, namely excitation by the broad
background of radiation emitted by a semiconductor diode laser. Combining our
result with atomic structure calculations yields 1.20 +- 0.01 s for the
lifetime of 3d D_{3/2}. We also use quantum jump observations to demonstrate
photon anti-bunching, and to estimate background pressure and heating rates in
the ion trap.

</DOC>
<DOC>
<DOCNO> 70020 </DOCNO>
Finite Temperature Meson Correlation Functions in HTL Approximation


  We calculate temporal correlators and their spectral functions with meson
quantum numbers in the deconfined phase of QCD using the hard thermal loop
(HTL) approximation for the quark propagator. Although this approach does not
result in a complete next-to-leading order perturbative calculation it takes
into account important medium effects such as thermal quark masses and Landau
damping in the quark-gluon plasma. We show that both effects lead to competing
modifications of the free mesonic correlation functions. We find that
correlators in scalar channels are only moderately influenced by the HTL medium
effects, while the HTL-vertex corrections lead to divergent vector correlators.

</DOC>
<DOC>
<DOCNO> 101385 </DOCNO>
An analogue of the Sommerfeld radiation condition for the Dirac operator


  A simple radiation condition at infinity for time-harmonic massive Dirac
spinors is proposed. This condition allows an analogue of the Cauchy integral
formula in unbounded domains for null-solutions of the Dirac equation to be
proved. The result is obtained with the aid of methods of quaternionic
analysis.

</DOC>
<DOC>
<DOCNO> 151593 </DOCNO>
On the perturbative expansion of boundary reflection factors of the


  The supersymmetric sinh-Gordon model on a half-line with integrable boundary
conditions is considered perturbatively to verify conjectured exact reflection
factors to one loop order. Propagators for the boson and fermion fields
restricted to a half-line contain several novel features and are developed as
prerequisites for the calculations.

</DOC>
<DOC>
<DOCNO> 9170 </DOCNO>
Magnetic dilution in the geometrically frustrated


  We investigate the spin dynamics of SrCr$_{9p}$Ga$_{12-9p}$O$_{19}$ for p
below and above the percolation threshold p_c using muon spin relaxation. Our
major findings are: (I) At T->0 the relaxation rate is T independent and
proportional to p^3, (II) the slowing down of spin fluctuation is activated
with an energy U which is also a linear function of p^3 and lim_{p-> 0}U = 8 K;
this energy scale could stem only from a single ion anisotropy, and (III) the p
dependence of the dynamical properties is identical below and above p_c,
indicating that they are controlled by local excitation.

</DOC>
<DOC>
<DOCNO> 83224 </DOCNO>
The SAT Phase Transition


  Phase transition is an important feature of SAT problem. For random k-SAT
model, it is proved that as r (ratio of clauses to variables) increases, the
structure of solutions will undergo a sudden change like satisfiability phase
transition when r reaches a threshold point. This phenomenon shows that the
satisfying truth assignments suddenly shift from being relatively different
from each other to being very similar to each other.

</DOC>
<DOC>
<DOCNO> 40675 </DOCNO>
Subleading corrections to parity violating pion photoproduction


  We compute the photon asymmetry $B_\gamma$ for near threshold parity
violating (PV) pion photoproduction through sub-leading order. We show that
sub-leading contributions involve a new combination of PV couplings not
included in previous analyses of hadronic PV. We argue that existing
constraints on the leading order contribution to $B_\gamma$ -- obtained from
the PV $\gamma$-decay of $^{18}$F -- suggest that the impact of the subleading
contributions may be more significant than expected from naturalness argumen

</DOC>
<DOC>
<DOCNO> 84336 </DOCNO>
New Einstein-Maxwell fields of Levi-Civita's type


  The method based on the Horsky-Mitskievitch conjecture is applied to the
Levi-Civita vacuum metric. It is shown, that every Killing vector is connected
with a particular class of Einstein-Maxwell fields and each of those classes is
found explicitly. Some of obtained classes are quite new. Radial geodesic
motion in constructed space-times is discussed and graphically illustrated in
the Appendix.

</DOC>
<DOC>
<DOCNO> 8109 </DOCNO>
Dissipative Landau-Zener Tunneling at Marginal Coupling


  The Landau-Zener transition in a two level system can be suppressed or
enhanced by coupling to an environment, depending on the temperature and the
environment spectral function. We consider the marginal spectral function, when
the dissipation effects are important for arbitrarily slow motion. Landau-Zener
transition rate demonstrates a non-trivial dependence of the on the ``bias'',
i. e. on the rate of the two energy levels relative motion. The Landau-Zener
transition is fully suppressed for the values of the bias below a threshold
bias set by the coupling strength. Above the threshold, the transition rate for
zero temperature is found using the instanton method. At finite temperature,
the Landau-Zener transition rate has a non-monotonic dependence on the coupling
strength, being suppressed at the strong coupling.

</DOC>
<DOC>
<DOCNO> 122642 </DOCNO>
Confronting Hydrodynamic Simulations Of Relativistic Jets With Data:


  We review recent relativistic hydrodynamic simulations of jets, and their
interpretation in terms of the results from linear stability analysis. These
studies show that, interpreted naively, the distribution of synchrotron
intensity will in general be a poor guide to the physical state (density and
pressure) of the underlying flow, and that even if the physical state can be
inferred, it, in turn, may prove to be a poor guide to the source dynamics, in
terms of the transport of energy and momentum from the central engine. However,
we demonstrate that an interplay of simulation and linear stability analysis
provides a powerful tool for elucidating the nature and character of structures
that jets may sustain. From such studies we can explain the complex behavior of
observed jets, which manifest both stationary and propagating structures,
without recourse to ad hoc macroscopic disturbances. This provides a framework
for the interpretation of multi-epoch total intensity data wherein an
understanding of the character of individual flow features will allow the
effects of physical state and dynamics to be deconvolved.

</DOC>
<DOC>
<DOCNO> 14026 </DOCNO>
Spin-Peierls transition of the first order in S=1 antiferromagnetic


  We investigate a one-dimensional S=1 antiferromagnetic Heisenberg model
coupled to a lattice distortion by a quantum Monte Carlo method. Investigating
the ground state energy of the static bond-alternating chain, we find that the
instability to a dimerized chain depends on the value of the spin-phonon
coupling, unlike the case of S=1/2. The spin state is the dimer state or the
uniform Haldane state depending on whether the lattice distorts or not,
respectively. At an intermediate value of the spin-phonon coupling, we find the
first-order transition between the two states. We also find the coexistence of
the two states.

</DOC>
<DOC>
<DOCNO> 117700 </DOCNO>
ROTSE All Sky Surveys for Variable Stars I: Test Fields


  The ROTSE-I experiment has generated CCD photometry for the entire Northern
sky in two epochs nightly since March 1998. These sky patrol data are a
powerful resource for studies of astrophysical transients. As a demonstration
project, we present first results of a search for periodic variable stars
derived from ROTSE-I observations. Variable identification, period
determination, and type classification are conducted via automatic algorithms.
In a set of nine ROTSE-I sky patrol fields covering about 2000 square degrees
we identify 1781 periodic variable stars with mean magnitudes between m_v=10.0
and m_v=15.5. About 90% of these objects are newly identified as variable.
Examples of many familiar types are presented. All classifications for this
study have been manually confirmed. The selection criteria for this analysis
have been conservatively defined, and are known to be biased against some
variable classes. This preliminary study includes only 5.6% of the total
ROTSE-I sky coverage, suggesting that the full ROTSE-I variable catalog will
include more than 32,000 periodic variable stars.

</DOC>
<DOC>
<DOCNO> 8198 </DOCNO>
Fermion propagator in a nontrivial background field


  We study the fermion propagator in a spatially varying classical background
field, and show that, contrary to common wisdom, it may get nontrivial gradient
corrections already at the first order in derivative expansion. This occurs
whenever the fermion self-energy acquires a spatially (or temporally) varying
pseudoscalar term, a simple example of which is given by a complex mass term
m(x)= m_R + i gamma_5 m_I. Such effective mass terms arise for example in
extensions of the Standard Model during the electroweak transition, and they
are crucial in providing the CP-violation necessary for electroweak
baryogenesis.

</DOC>
<DOC>
<DOCNO> 151491 </DOCNO>
Fermionic zero-norm states and enlarged supersymmetries of Type II


  We calculate the NS-R fermionic zero-norm states of type II string spectrum.
The massless and some possible massive zero-norm states are identified to be
responsible for the space-time supersymmetry. The existence of other fermionic
massive zero-norm states with higher spinor-tensor indices correspond to new
enlarged boson-fermion symmetries of the theory at high energy. We also discuss
the R-R charges and R-R zero-norm states and justify that perturbative string
does not carry the massless R-R charges. However, the existence of some massive
R-R zero-norm states make us speculate that string may carry some massive R-R
charges.

</DOC>
<DOC>
<DOCNO> 71484 </DOCNO>
Soft hadron production in pp interactions up to ISR energies


  Soft hadron production is described as a two-step process, where the
interaction of the partonic constituents of the colliding hadrons leads to the
production of intermediate subsystems (fireballs), which decay subsequently
into hadrons. The weights of the various final states are derived from the
corresponding phase-space factors modified by empirical transition elements.
The results compare well with data at energies between particle production
thresholds and ISR energies. Special emphasis is put on correlation data, which
offer the opportunity to shed some light on the question whether particle
production proceeds via fireballs or strings.

</DOC>
<DOC>
<DOCNO> 100248 </DOCNO>
The Schr\"odinger operator on graphs and topology


  Symplectic vector-valued scalar product is constructed on the spaces of
solutions of the real discrete Shrodinger equation with fixed value of the
spectral parameter on graphs. It takes values in the first homology group of
the graph. This scalar product plays fundamental role in the Scattering theory
for the graphs with tails. In particular, all unitarity properties of
scattering follow from elementary symplectic geometry

</DOC>
<DOC>
<DOCNO> 169646 </DOCNO>
Coherent states, displaced number states and Laguerre polynomial states


  The ladder operator formalism of a general quantum state for su(1,1) Lie
algebra is obtained. The state bears the generally deformed oscillator
algebraic structure. It is found that the Perelomov's coherent state is a
su(1,1) nonlinear coherent state. The expansion and the exponential form of the
nonlinear coherent state are given. We obtain the matrix elements of the
su(1,1) displacement operator in terms of the hypergeometric functions and the
expansions of the displaced number states and Laguerre polynomial states are
followed. Finally some interesting su(1,1) optical systems are discussed.

</DOC>
<DOC>
<DOCNO> 169759 </DOCNO>
Quantum theory of self-action of ultrashort light pulses in an inertial


  The systematic theory of the formation of the short light pulses in the
squeezed state during the propagation in a medium with inertial Kerr
nonlinearity is developed. The algebra of time-dependent Bose-operators is
elaborated and the normal-ordering theorem for them is formulated. It is
established that the spectral region where the quadrature fluctuations are
weaker than the shot-noise, depends on both the relaxation time of the
nonlinearity and the magnitude of the nonlinear phase shift. It is also shown
that the frequency at which suppression of the fluctuation is greatest can be
controlled by adjusting the phase of the initial coherent light pulse. The
spectral correlation function of photons is introduced and photon antibunching
is found.

</DOC>
<DOC>
<DOCNO> 102568 </DOCNO>
The multiple zeta value algebra and the stable derivation algebra


  The MZV algebra is the graded algebra over ${\bold Q}$ generated by all
multiple zeta values. The stable derivation algebra is a graded Lie algebra
version of the Grothendieck-Teichm\"{u}ller group. We shall show that there is
a canonical surjective $\bold Q $-linear map from the graded dual vector space
of the stable derivation algebra over $\bold Q$ to the new-zeta space, the
quotient space of the sub-vector space of the MZV algebra whose grade is
greater than 2 by the square of the maximal ideal. As a corollary, we get an
upper-bound for the dimension of the graded piece of the MZV algebra at each
weight in terms of the corresponding dimension of the graded piece of the
stable derivation algebra. If some standard conjectures by Y. Ihara and P.
Deligne concerning the structure of the stable derivation algebra hold, this
will become a bound conjectured in Zagier's talk at 1st ECM. Via the stable
derivation algebra, we can compare the new-zeta space with the $l$-adic Galois
image Lie algebra which is associated with the Galois representation on the
pro-$l$ fundamental group of $\bold P ^1_ {\overline{\bold Q}}-{0,1,\infty}$ .

</DOC>
<DOC>
<DOCNO> 120748 </DOCNO>
Pair production with electron capture in peripheral collisions of


  The production of electron-positron pairs with the capture of the electron in
an atomic orbital is investigated for the conditions of the Relativistic Heavy
Ion Collider (RHIC) and the Large Hadron Collider LHC). Dirac wave functions
for the leptons are used, taking corrections to orders of Z.alpha into account.
The dependence on the transverse momentum transfer is studied and the accuracy
of the equivalent photon approximation is discussed as a function of the
nuclear charge.

</DOC>
<DOC>
<DOCNO> 69294 </DOCNO>
SUSY Dark Matter


  Several new effects have been investigated in recent analyses of
supersymmetric dark matter. These include the effects of the uncertainties of
wimp velocity distributions, of the uncertainties of quark densities, of large
CP violating phases, of nonuniversalities of the soft SUSY breaking parameters
at the unification scale and of coannihilation on supersymmetric dark matter.
We review here some of these with emphasis on the effects of nonuniversalities
of the gaugino masses at the unification scale on the neutralino-proton
cross-section from scalar interactions. The review encompasses several models
where gaugino mass nonuniversalities occur including SUGRA models and D brane
models. One finds that gaugino mass nonuniversalities can increase the scalar
cross-sections by as much as a factor of 10 and also significantly extend the
allowed range of the neutralino mass consistent with constraints up to about
500 GeV. These results have important implications for the search for
supersymmetric dark matter.

</DOC>
<DOC>
<DOCNO> 150547 </DOCNO>
Wilson loops in the adjoint representation and multiple vacua in


  $QCD_2$ with fermions in the adjoint representation is invariant under
$SU(N)/Z_N$ and thereby is endowed with a non-trivial vacuum structure
(k-sectors). The static potential between adjoint charges, in the limit of
infinite mass, can be therefore obtained by computing Wilson loops in the pure
Yang-Mills theory with the same non-trivial structure. When the (Euclidean)
space-time is compactified on a sphere $S^2$, Wilson loops can be exactly
expressed in terms of an infinite series of topological excitations
(instantons). The presence of k-sectors modifies the energy spectrum of the
theory and its instanton content. For the exact solution, in the limit in which
the sphere is decompactified, a k-sector can be mimicked by the presence of
k-fundamental charges at $\infty$, according to a Witten's suggestion. However
this property neither holds before decompactification nor for the genuine
perturbative solution which corresponds to the zero-instanton contribution on
$S^2$.

</DOC>
<DOC>
<DOCNO> 122960 </DOCNO>
On Ultrasmall Silicate Grains in the Diffuse Interstellar Medium


  The abundance of both amorphous and crystalline silicates in very small
grains is limited by the fact that the 10 micron silicate emission feature is
not detected in the diffuse ISM. On the basis of the observed IR emission
spectrum for the diffuse ISM, the observed ultraviolet extinction curve, and
the 10 micron silicate absorption profile, we obtain upper limits on the
abundances of ultrasmall (a < 15 Angstrom) amorphous and crystalline silicate
grains.
  Contrary to previous work, as much as ~20% of interstellar Si could be in a <
15 Angstrom silicate grains without violating observational constraints. Not
more than ~5% of the Si can be in crystalline silicates (of any size).

</DOC>
<DOC>
<DOCNO> 99421 </DOCNO>
Superselection Theory for Subsystems


  An inclusion of observable nets satisfying duality induces an inclusion of
canonical field nets. Any Bose net intermediate between the observable net and
the field net and satisfying duality is the fixed-point net of the field net
under a compact group. This compact group is its canonical gauge group if the
occurrence of sectors with infinite statistics can be ruled out for the
observable net and its vacuum Hilbert space is separable.

</DOC>
<DOC>
<DOCNO> 80964 </DOCNO>
$K\to\pi\pi$ Decays with Domain Wall Fermions: Lattice Matrix Elements


  We present a lattice calculation of the $K\to\pi$ and $K\to 0$ matrix
elements of the $\Delta S=1$ effective weak Hamiltonian which can be used to
determine $\epsilon^\prime/\epsilon$ and the $\Delta I=1/2$ rule for $K$ decays
in the Standard Model. The matrix elements for $K\to\pi\pi$ decays are related
to $K\to\pi$ and $K\to 0$ using lowest order chiral perturbation theory. We
also present results for the kaon $B$ parameter, $B_K$. Our quenched domain
wall fermion simulation was done at $\beta=6.0$ ($a^{-1}\approx 2$ GeV),
lattice size $16^3\times 32\times 16$, and domain wall height $M_5=1.8$.

</DOC>
<DOC>
<DOCNO> 85279 </DOCNO>
General Electric-Magnetic decomposition of fields, positivity and


  We show how to generalize the classical electric-magnetic decomposition of
the Maxwell or the Weyl tensors to arbitrary fields described by tensors of any
rank in general $n$-dimensional spacetimes of Lorentzian signature. The
properties and applications of this decomposition are reviewed. In particular,
the definition of tensors quadratic in the original fields and with important
positivity properties is given. These tensors are usually called "super-energy"
(s-e) tensors, they include the traditional energy-momentum, Bel and
Bel-Robinson tensors, and satisfy the so-called Dominant Property, which is a
straightforward generalization of the classical dominant energy condition
satisfied by well-behaved energy-momentum tensors. We prove that, in fact, any
tensor satisfying the dominant property can be decomposed as a finite sum of
the s-e tensors. Some remarks about the conservation laws derivable from s-e
tensors, with some explicit examples, are presented. Finally, we will show how
our results can be used to provide adequate generalizations of the Rainich
conditions in general dimension and for any physical field.

</DOC>
<DOC>
<DOCNO> 83150 </DOCNO>
A note on the Declarative reading(s) of Logic Programming


  This paper analyses the declarative readings of logic programming. Logic
programming - and negation as failure - has no unique declarative reading. One
common view is that logic programming is a logic for default reasoning, a
sub-formalism of default logic or autoepistemic logic. In this view, negation
as failure is a modal operator. In an alternative view, a logic program is
interpreted as a definition. In this view, negation as failure is classical
objective negation. From a commonsense point of view, there is definitely a
difference between these views. Surprisingly though, both types of declarative
readings lead to grosso modo the same model semantics. This note investigates
the causes for this.

</DOC>
<DOC>
<DOCNO> 83354 </DOCNO>
Selectional Restrictions in HPSG


  Selectional restrictions are semantic sortal constraints imposed on the
participants of linguistic constructions to capture contextually-dependent
constraints on interpretation. Despite their limitations, selectional
restrictions have proven very useful in natural language applications, where
they have been used frequently in word sense disambiguation, syntactic
disambiguation, and anaphora resolution. Given their practical value, we
explore two methods to incorporate selectional restrictions in the HPSG theory,
assuming that the reader is familiar with HPSG. The first method employs HPSG's
Background feature and a constraint-satisfaction component pipe-lined after the
parser. The second method uses subsorts of referential indices, and blocks
readings that violate selectional restrictions during parsing. While
theoretically less satisfactory, we have found the second method particularly
useful in the development of practical systems.

</DOC>
<DOC>
<DOCNO> 85174 </DOCNO>
Static black holes in scalar tensor gravity


  We study static black hole solutions in scalar tensor gravity. We present
exact solutions in hiperextended models with a quadratic scalar potential.

</DOC>
<DOC>
<DOCNO> 102375 </DOCNO>
The $M_{L}(z);C_{L}(z);W_{L}(z)$ associated Laguerre Polynomials


  In a previous paper we deformed Hermite polynomials to three associated
polynomials .Here we apply the same deformation to Laguerre polynomials .

</DOC>
<DOC>
<DOCNO> 120244 </DOCNO>
Improved timing formula for the PSR B1257+12 planetary system


  We present a new analysis of the dynamics of the planetary system around the
pulsar B1257+12. A semi-analytical theory of perturbation between
terrestrial-mass planets B and C is developed and applied to improve
multi-orbit timing formula for this object. We use numerical simulations of the
pulse arrival times for PSR B1257+12 to demonstrate that our new timing model
can serve as a toll to determine the masses of the two planets.

</DOC>
<DOC>
<DOCNO> 13408 </DOCNO>
Recent theories of glasses as out of equilibrium systems


  We discuss a theoretical approach to structural glasses as they happen in
real situations. Older ideas based on `configurational entropy', on `fictive
temperatures' and on Edwards' `compactivity' are sharpened and unified in an
out of equilibrium context. The picture is such that it may be supported or
disproved by an experimental test, which we describe.

</DOC>
<DOC>
<DOCNO> 70038 </DOCNO>
How to resum long-distance contributions to the QCD pressure?


  The strict coupling constant expansion for the free energy of hot QCD plasma
shows bad convergence at all reasonable temperatures, and does not agree well
with its 4d lattice determination. This has recently lead to various refined
resummations, whereby the agreement with the lattice result should improve, at
the cost of a loss of a formal agreement with the coupling constant expansion
and particularly with its large infrared sensitive ``long-distance''
contributions. We show here how to resum the dominant long-distance effects by
using a 3d effective field theory, and determine their magnitude by simple
lattice Monte Carlo simulations.

</DOC>
<DOC>
<DOCNO> 170412 </DOCNO>
From Single to Multiple-Photon Decoherence in an Atom Interferometer


  We measure the decoherence of a spatially separated atomic superposition due
to spontaneous photon scattering. We observe a qualitative change in
decoherence versus separation as the number of scattered photons increases, and
verify quantitatively the decoherence rate constant in the many-photon limit.
Our results illustrate an evolution of decoherence consistent with general
models developed for a broad class of decoherence phenomenon.

</DOC>
<DOC>
<DOCNO> 152066 </DOCNO>
Cohomological Yang-Mills Theories on Kahler 3-Folds


  We study topological gauge theories with N=(2,0) supersymmetry based on
stable bundles on general Kahler 3-folds. In order to have a theory that is
well defined and well behaved, we consider a model based on an extension of
the usual holomorphic bundle by including a holomorphic 3-form. The correlation
functions of the model describe complex 3-dimensional generalizations of
Donaldson-Witten type invariants. We show that the path integral can be written
as a sum of contributions from stable bundles and a complex 3-dimensional
version of Seiberg-Witten monopoles. We study certain deformations of the
theory, which allow us to consider the situation of reducible connections. We
shortly discuss situations of reduced holonomy. Afterdimensional reduction to a
Kahler 2-fold, the theory reduces to Vafa-Wittentheory. On a Calabi-Yau 3-fold,
the supersymmetry is enhanced to N=(2,2). This model may be used to describe
classical limits of certain compactifications of(matrix) string theory.

</DOC>
<DOC>
<DOCNO> 83075 </DOCNO>
Quantum lower bounds by quantum arguments


  We propose a new method for proving lower bounds on quantum query algorithms.
Instead of a classical adversary that runs the algorithm with one input and
then modifies the input, we use a quantum adversary that runs the algorithm
with a superposition of inputs. If the algorithm works correctly, its state
becomes entangled with the superposition over inputs. We bound the number of
queries needed to achieve a sufficient entanglement and this implies a lower
bound on the number of queries for the computation.
  Using this method, we prove two new $\Omega(\sqrt{N})$ lower bounds on
computing AND of ORs and inverting a permutation and also provide more uniform
proofs for several known lower bounds which have been previously proven via
variety of different techniques.

</DOC>
<DOC>
<DOCNO> 122489 </DOCNO>
The effect of 3-He diffusion on the pulsational spectra of DBV models


  We consider envelopes of DB white dwarfs which are not composed of pure 4-He,
but rather a mixture of 3-He and 4-He. Given this assumption, the same
diffusive processes which produce a relatively pure H layer overlying a He
layer in the DA's should work to produce a 3-He layer overlying a 4-He layer in
the DB's. We examine the relevant timescales for diffusion in these objects,
and compare them to the relevant evolutionary timescales in the context of the
DBV white dwarfs. We then explore the consequences which 3-He separation has on
the pulsational spectra of DBV models. Since GD 358 is the best-studied member
of this class of variables, we examine fits to its observed pulsation spectrum.
We find that the inclusion of a 3-He layer results in a modest improvement in a
direct fit to the periods, while a fit to the period spacings is significantly
improved.

</DOC>
<DOC>
<DOCNO> 70495 </DOCNO>
Quarkonium production and NRQCD matrix elements


  Most recent calculations of quarkonium production are based on the NRQCD
factorization formalism. This formalism is reviewed. To make predictions about
specific cross section, universal NRQCD matrix elements need to be extracted
from experiments. Extractions from different experimental situations are
compared, with some emphasis on the extraction from LEP.

</DOC>
<DOC>
<DOCNO> 101807 </DOCNO>
Heisenberg duoble, pentagon equation, structure and classification of


  The study of the pentagon (fusion) equation leds to the Structure and the
Classification theorem for finite dimenasional Hopf algebras: there exists a
one to one correspondence between the set of types of n-dimensional Hopf
algebtras and the set of the orbits of the resticted Jordan action $GL_n(k)
\times M_n(k)\otimes M_n(k) \to M_n(k) \otimes M_nk$ $(u, R) \to (u\otimes u)R
(u\otimes u)^{-1}$, the representatives of wich are invertible solutions of
length n of the pentagon equation.

</DOC>
<DOC>
<DOCNO> 68059 </DOCNO>
Automatic Feynman diagram calculation with xloops--a short overview


  xloops is a program package that calculates Feynman diagrams by using
computer algebra systems. In this paper it is shown which problems to be solved
by computer algebra arise during such calculations, and how this problems are
handled in the framework of xloops.

</DOC>
<DOC>
<DOCNO> 170532 </DOCNO>
Experimental Test for Absence of R-Term in Schroedinger Equation in


  We point out that the presence of a term proportional to the scalar curvature
in the Schroedinger equation in curved space can easily be detected in atomic
spectra with Russel-Saunders coupling by a violation of the Lande interval rule
for adjacent levels E_J-E_{J-1} propto J.

</DOC>
<DOC>
<DOCNO> 101815 </DOCNO>
Rank jumps in Codimension 2 A-Hypergeometric Systems


  The holonomic rank of the A-hypergeometric system H_A(\beta) is shown to
depend on the parameter vector \beta when the underlying toric ideal I_A is a
non Cohen Macaulay codimension 2 toric ideal. The set of exceptional parameters
is usually infinite.

</DOC>
<DOC>
<DOCNO> 68457 </DOCNO>
Neutrino scattering on polarized electron target as a test of neutrino


  We suggest to use a polarized electron target for improving the sensitivity
of the search for the neutrino magnetic moment to the level $\sim
3\cdot10^{-13}\mu_B$ in the processes of neutrino (antineutrino) -- electron
scattering. It is shown that in this case the weak interaction term in the
total cross section is significantly suppressed comparing with unpolarized
case, but the electromagnetic term does not depend on electron polarization.

</DOC>
<DOC>
<DOCNO> 101889 </DOCNO>
A discrete density matrix theory for atoms in strong magnetic fields


  This paper concerns the asymptotic ground state properties of heavy atoms in
strong, homogeneous magnetic fields. In the limit when the nuclear charge Z
tends to infinity with the magnetic field B satisfying B >> Z^{4/3} all the
electrons are confined to the lowest Landau band. We consider here an energy
functional, whose variable is a sequence of one-dimensional density matrices
corresponding to different angular momentum functions in the lowest Landau
band. We study this functional in detail and derive various interesting
properties, which are compared with the density matrix (DM) theory introduced
by Lieb, Solovej and Yngvason. In contrast to the DM theory the variable
perpendicular to the field is replaced by the discrete angular momentum quantum
numbers. Hence we call the new functional a discrete density matrix (DDM)
functional. We relate this DDM theory to the lowest Landau band quantum
mechanics and show that it reproduces correctly the ground state energy apart
from errors due to the indirect part of the Coulomb interaction energy.

</DOC>
<DOC>
<DOCNO> 9756 </DOCNO>
Vortex melting and decoupling transitions in YBa$_{2}$Cu$_{4}$O$_{8}$


  The vortex correlation along the c-axis in high quality single crystals of
YBa$_{2}$Cu$_{4}$O$_{8}$ has been investigated as a function of temperature T
in different magnetic fields, using the quasi-flux transformer configuration. A
simultaneous sharp drop associated with the vortex lattice melting is observed
in both the primary and secondary voltages(V$_{top}$ and V$_{bot}$). Just above
the melting temperature, the vortices form three-dimensional line liquid with
the correlation length along the c direction $L_{c}\leq $ t, the sample
thickness. The temperature where a resistive peak in R$_{bot}$ develops
corresponds to the decoupling temperature T$_{d}$ at which the vortices loose
their correlation along the c-direction and they dissolve into the two
dimensional pancake vortices. The H-T phase diagram for the
YBa$_{2}$Cu$_{4}$O$_{8}$ single crystal is obtained.

</DOC>
<DOC>
<DOCNO> 117890 </DOCNO>
Ages of late spectral type Vega-like stars


  We have estimated the ages of eight late-type Vega-like stars by using
standard age dating methods for single late-type stars, e.g., location on the
color magnitude diagram, Li 6708 angstrom absorption, CaII H&K emission, X-ray
luminosity, and stellar kinematic population. With the exception of the very
unusual pre-main sequence star system HD 98800, all the late-type Vega-like
stars are the same age as the Hyades cluster (600-800 Myr) or older.

</DOC>
<DOC>
<DOCNO> 151205 </DOCNO>
Monopoles and Strings in Noncommutative Gauge Theory


  We study some non-perturbative aspects of noncommutative gauge theories. We
find analytic solutions of the equations of motion, for noncommutative U(1)
gauge theory, that describe magnetic monopoles with a finite tension string
attached. These solutions are non-singular, finite and sourceless. We identify
the string with the projection of a D-string ending on a D3-brane in the
presence of a constant B-field.

</DOC>
<DOC>
<DOCNO> 10243 </DOCNO>
Shift in the velocity of a front due to a cut-off


  We consider the effect of a small cut-off epsilon on the velocity of a
traveling wave in one dimension. Simulations done over more than ten orders of
magnitude as well as a simple theoretical argument indicate that the effect of
the cut-off epsilon is to select a single velocity which converges when epsilon
tends to 0 to the one predicted by the marginal stability argument. For small
epsilon, the shift in velocity has the form K(log epsilon)^(-2) and our
prediction for the constant K agrees very well with the results of our
simulations. A very similar logarithmic shift appears in more complicated
situations, in particular in finite size effects of some microscopic stochastic
systems. Our theoretical approach can also be extended to give a simple way of
deriving the shift in position due to initial conditions in the
Fisher-Kolmogorov or similar equations.

</DOC>
<DOC>
<DOCNO> 99541 </DOCNO>
Quasi-Hopf algebras associated with semisimple Lie algebras and complex


  We construct quasi-Hopf algebras associated with a semisimple Lie algebra, a
complex curve and a rational differential. This generalizes our previous joint
work with V. Rubtsov (Israel J. Math. (1999) and q-alg/9608005).

</DOC>
<DOC>
<DOCNO> 10536 </DOCNO>
The nondeterministic Nagel-Schreckenberg traffic model with open


  We study the phases of the Nagel-Schreckenberg traffic model with open
boundary conditions as a function of the randomization probability p > 0 and
the maximum velocity ${v}_{max} > 1$. Due to the existence of "buffer sites"
which enhance the free flow region, the behaviour is much richer than that of
the related asymmetric exclusion process (ASEP, {v}_{max} = 1$). Such sites
exist for ${v}_{max} \ge 3$ and p < ${p}_{c}$ where the phase diagram is
qualitatively similar to the p = 0 case: there is a free flow and a jamming
phase separated by a line of first-order phase transitions. For p > ${p}_{c}$
an additional maximum current phase occurs like for the ASEP. The density
profile decays in the maximum current phase algebraically with an exponent
$\gamma \approx 2/3$ for all ${v}_{max} \ge 2$ indicating that these models
belong to another universality class than the ASEP where $\gamma = 1/2$.

</DOC>
<DOC>
<DOCNO> 71003 </DOCNO>
Energy dependence of the quark masses and mixings


  The one loop Renormalization Group Equations for the Yukawa couplings of
quarks are solved. From the solution we find the explicit energy dependence on
$t=\ln E/\mu $ of the evolution of the {\em down} quark masses $q=d,s,b$ from
the grand unification scale down to the top quark mass $m_{t}$. These results
together with the earlier published evolution of the {\em up} quark masses
completes the pattern of the evolution of the quark masses. We also find the
energy dependence of the absolute values of the Cabibbo-Kobayashi-Maskawa (CKM)
matrix $|V_{ij}|$. The interesting property of the evolution of the CKM matrix
and the ratios of the quark masses: $m_{u,c}/m_{t}$ and $m_{d,s}/m_{b}$ is that
they all depend on $t$ through only one function of energy $h(t)$.

</DOC>
<DOC>
<DOCNO> 101256 </DOCNO>
Diffraction of wave packets in space and time in three dimensions


  A simple formula for the scattering of wave packets from a square well at
long times is derived. The expression shows that the phenomenon of wave packet
diffraction in space and time exists in three dimensions also. An experiment
for the verification of the phenomenon is described and simulated numerically.

</DOC>
<DOC>
<DOCNO> 70883 </DOCNO>
Model-Independent Confirmation of the $\sigma$-Meson below 1 GeV and


  In the model-independent approach consisting in the immediate application to
the analysis of experimental data of such general principles as analyticity and
unitarity, a confirmation of the $\sigma$-meson at $\sim$ 665 MeV and an
indication for the glueball nature of the $f_0(1500)$ state are obtained on the
basis of a simultaneous description of the isoscalar s-wave channel of the
$\pi\pi$ scattering (from the threshold up to 1.9 GeV) and of the $\pi\pi\to
K\bar{K}$ process (from the threshold to $\sim$ 1.4 GeV where the 2-channel
unitarity is valid). A parameterless description of the $\pi\pi$ background is
first given by allowance for the left-hand branch-point in the proper
uniformizing variable. It is shown that the large $\pi\pi$-background, usually
obtained, combines, in reality, the influence of the left-hand branch-point and
the contribution of a very wide resonance at $\sim$ 665 MeV. The coupling
constants of the observed states with the $\pi\pi$ and $K\bar{K}$ systems and
lengths of the $\pi\pi$ and $K\bar{K}$ scattering are obtained.

</DOC>
<DOC>
<DOCNO> 8047 </DOCNO>
O(4)-Invariant Formulation of the Nodal Liquid


  We consider the O(4) symmetric point in the phase diagram of an electron
system in which there is a transition between d_{x^2 - y^2} density-wave order
and d_{x^2 - y^2} superconductivity. If the pseudospin $SU(2)\subset O(4)$
symmetry is disordered by quantum fluctuations, the Nodal Liquid can result. In
this context, we (1) construct a pseudospin $\sigma$-model; (2) discuss its
topological excitations; (3) point out the possibility of a {\it
pseudospin-Peierls} state and (4) propose a phase diagram for the underdoped
cuprate superconductors.

</DOC>
<DOC>
<DOCNO> 70042 </DOCNO>
The pi pi S-wave scattering lengths


  We match the known chiral perturbation theory representation of the pi pi
scattering amplitude to two loops with a phenomenological description that
relies on the Roy equations. On this basis, the corrections to Weinberg's low
energy theorems for the S-wave scattering lengths are worked out to second
order in the expansion in powers of the quark masses. The resulting
predictions, a00=0.220 \pm 0.005, a20=-0.0444 \pm 0.0010, contain remarkably
small uncertainties and thus allow a very sensitive experimental test of the
hypothesis that the quark condensate is the leading order parameter of the
spontaneously broken chiral symmetry.

</DOC>
<DOC>
<DOCNO> 8192 </DOCNO>
The local magnetic moments and hyperfine magnetic fields in disordered


  The local magnetic moments and hyperfine magnetic fields (HFF) in the ordered
alloys Fe_{15}Sn and Fe_{15}Si are calculated with the first-principles
full-potential linear augmented plane wave (FP LAPW) method. The results are
compared with the experimental data on Fe-M (M=Si, Sn) disordered alloys at
small metalloid concentration. The relaxation of the lattice around the
impurity and its influence on the quantities under consideration are studied.
The mechanism of the local magnetic moment formation is described. It is proved
that the main distinction between these alloys is connected with the different
lattice parameters. Three contributions to the HFF are discussed: the
contributions of the core and valence electron polarization to the
Fermi-contact part, and the contibution from the orbital magnetic moment.

</DOC>
<DOC>
<DOCNO> 123263 </DOCNO>
Indicator of Exo-Solar Planet(s) in the Circumstellar Disk Around Beta


  Our efficient numerical approach has been applied to modeling the asymmetric
circumstellar dust disk around Beta Pictoris as observed with the HST/STIS. We
present a new model on the origin of the warping of the Beta Pic disk. We
suggest that the observed warp is formed by the gravitational influence of a
planet with a mass of about 10 masses of Earth, at a distance of 70 AU, and a
small inclination ($\sim 2.5^\circ$) of the planetary orbit to the main dust
disk. Results of our modeling are compared with the STIS observations.

</DOC>
<DOC>
<DOCNO> 151174 </DOCNO>
Exponential Hierarchy From Spacetime Variable String Vacua


  It is shown that non-supersymmetric spacetime varying string vacua can lead
to an exponential hierarchy between the electroweak and the gravitational
scales. The hierarchy is naturally generated by a string coupling of O(1).

</DOC>
<DOC>
<DOCNO> 9134 </DOCNO>
Emergence of intense jets and Jupiter Great Red Spot as maximum entropy


  We explain the emergence and robustness of intense jets in highly turbulent
planetary atmospheres, like on Jupiter, by a general approach of statistical
mechanics of potential vorticity patches. The idea is that potential vorticity
mixing leads to the formation of a steady organized coarse grained flow,
corresponding to the statistical equilibrium state. Our starting point is the
quasi-geostrophic 1-1/2 layer model, and we consider the relevant limit of a
small Rossby radius of deformation. Then narrow jets are obtained, scaling like
the Rossby radius of deformation. These jets can be either zonal, or closed
into a ring bounding a vortex. Taking into account the effect of the beta
effect and a sublayer deep shear flow, we predict an organization of the
turbulent atmospheric layer into an oval-shaped vortex amidst a background
shear. Such an isolated vortex is centered over an extremum of the equivalent
topography (determined by the deep shear flow and beta-effect). This prediction
is in agreement with analysis of wind data in major Jovian vortices (Great Red
Spot and Oval BC).

</DOC>
<DOC>
<DOCNO> 150758 </DOCNO>
Scalar Field in Any Dimension from the Higher Spin Gauge Theory


  We formulate the equations of motion of a free scalar field in the flat and
$AdS$ space of an arbitrary dimension in the form of some "higher spin"
covariant constancy conditions. Klein-Gordon equation is interpreted as a
non-trivial cohomology of a certain "\sgm-complex". The action principle for a
scalar field is formulated in terms of the "higher-spin" covariant derivatives
for an arbitrary mass in $AdS_d$ and for a non-zero mass in the flat space. The
constructed action is shown to be equivalent to the standard first-order
Klein-Gordon action at the quadratic level but becomes different at the
interaction level because of the presence of an infinite set of auxiliary
fields which do not contribute at the free level. The example of Yang-Mills
current interaction is considered in some detail. It is shown in particular how
the proposed action generates the pseudolocally exact form of the matter
currents in $AdS_d$.

</DOC>
<DOC>
<DOCNO> 69936 </DOCNO>
Single spin asymmetries in $\gamma^* \gamma \to \pi \pi \pi$ at large


  The $\gamma^* \gamma \to \pi \pi \pi$ reaction is analysed in QCD at large
photon virtuality Q and small hadronic mass W. Its amplitude factorizes in a $3
\pi$ generalized distribution amplitude and a hard subprocess $\gamma^* \gamma
\to q \bar q$ or $\gamma^* \gamma \to g g$. The interference of this process
with a Brehmsstrahlung process in e e or $e \gamma$ collisions gives rise to
interesting single spin asymmetries, particularly when W is near the $\omega$
mass.

</DOC>
<DOC>
<DOCNO> 71332 </DOCNO>
The Fayet-Iliopoulos D-term and its renormalisation in the MSSM


  We consider the renormalisation of the Fayet-Iliopoulos D-term in a
softly-broken supersymmetric gauge theory with a non-simple gauge group
containing an abelian factor, and present the associated beta-function through
three loops. We also include in an appendix the result for several abelian
factors. We specialise to the case of the minimal supersymmetric standard model
(MSSM), and investigate the behaviour of the Fayet-Iliopoulos coupling for
various boundary conditions at the unification scale. We focus particularly on
the case of non-standard soft supersymmetry breaking couplings, for which the
Fayet-Iliopoulos coupling evolves significantly between the unification scale
and the weak scale.

</DOC>
<DOC>
<DOCNO> 67792 </DOCNO>
The Rest-Frame Darwin Potential from the Lienard-Wiechert Solution in


  In the semiclassical approximation in which the electric charges of scalar
particles are described by Grassmann variables ($Q_i^2=0, Q_iQ_j\ne 0$), it is
possible to re-express the Lienard-Wiechert potentials and electric fields in
the radiation gauge as phase space functions, because the difference among
retarded, advanced, and symmetric Green functions is of order Q_i^2. By working
in the rest-frame instant form of dynamics, the elimination of the
electromagnetic degrees of freedom by means of suitable second classs
contraints leads to the identification of the Lienard-Wiechert reduced phase
space containing only N charged particles with mutual action-at-a-distance
vector and scalar potentials. A Darboux canonical basis of the reduced phase
space is found. This allows one to re-express the potentials for arbitrary N as
a unique effective scalar potential containing the Coulomb potential and the
complete Darwin one, whose 1/c^2 component agrees for with the known
expression. The effective potential gives the classical analogue of all static
and non-static effects of the one-photon exchange Feynman diagram of scalar
electrodynamics.

</DOC>
<DOC>
<DOCNO> 12047 </DOCNO>
Two remarks on wetting and emulsions


  This paper is extracted from an opening address given at the workshop
"Wetting: from microscopic origins to industrial applications" (Giens, May
  6-12, 2000). It discusses two special points a) the nature of line energies
for a contact line b) the aging of emulsions.

</DOC>
<DOC>
<DOCNO> 13931 </DOCNO>
Breakdown of the Landauer bound for information erasure in the quantum


  A known aspect of the Clausius inequality is that an equilibrium system
subjected to a squeezing $\d S$ of its entropy must release at least an amount
$|\dbarrm Q|=T|\d S|$ of heat. This serves as a basis for the Landauer
principle, which puts a lower bound $T\ln 2$ for the heat generated by erasure
of one bit of information. Here we show that in the world of quantum
entanglement this law is broken. A quantum Brownian particle interacting with
its thermal bath can either generate less heat or even {\it adsorb} heat during
an analogous squeezing process, due to entanglement with the bath. The effect
exists even for weak but fixed coupling with the bath, provided that
temperature is low enough. This invalidates the Landauer bound in the quantum
regime, and suggests that quantum carriers of information can be much more
efficient than assumed so far.

</DOC>
<DOC>
<DOCNO> 70191 </DOCNO>
Higher twists and maxima for DIS on nuclei in high density QCD region


  We show that the ratio of different structure functions have a maximum which
depends on $x_B$ and $A$. We argue that these maxima are proportional to the
saturation scale. The analysis of leading and higher twist contributions for
different observables is given with the aim of determining the kinematic region
where high parton density effects could be seen experimentally.

</DOC>
<DOC>
<DOCNO> 150409 </DOCNO>
U(1) Connection, Nonlinear Dirac-like Equations and Seiberg-Witten


  By analysing the work of Campolattaro we argue that the second Seiberg-Witten
equation over the Spin^c_4 manifold, i.e., F^+_{ij}=< M,S_ij M >, is the
generalization of the Campolattaro's description of the electromagnetic field
tensor F^{\mu\nu} in the bilinear form F^{\mu\nu}=\bar{\Psi} S^{\mu\nu}\Psi. It
turns out that the Seiberg-Witten equations (also the perturbed Seiberg-Witten
equations) can be well understood from this point of view. We suggest that the
second Seiberg-Witten equation can be replaced by a nonlinear Dirac-like
Equation. We also derive the spinor representation of the connection on the
associated unitary line bundle over the Spin^c_4 manifold.

</DOC>
<DOC>
<DOCNO> 11420 </DOCNO>
NMR properties of a one-dimesional Cu-O model


  We obtain the Knight shifts and the relaxation rates related to the Fermi
contact interaction term for a one-dimensional Cu-O model using bosonization
technique. We consider the small interaction limit at half-filling and away
from half-filling. In this framework we predict that the antiferromagnetic
contribution to the relaxation rate of the nuclear oxygen spin is completely
suppressed even away from half-filling, when the temperature is low enough. In
the strong interaction limit at half-filling we compute the effective Fermi
contact interaction performing a Gutzwiller projection. Both limits suggest
that the one-dimensional versions of the Mila-Rice and of the Shastry scenarios
of transferred hyperfine couplings which were proposed to explain the NMR
measurements for High-T_c cuprates fail in a one-dimensional situation.

</DOC>
<DOC>
<DOCNO> 72049 </DOCNO>
Large lepton mixing and supernova 1987A


  We reconsider the impact of $\bar\nu_e \leftrightarrow \bar\nu_{\mu,\tau}$
neutrino oscillations on the observed $\bar\nu_e$ signal of supernova SN 1987A.
Performing a maximum-likelihood analysis using as fit parameters the released
binding energy $\Eb$ and the average neutrino energy $\Ee$, we find as previous
analyses that $\bar\nu_e \leftrightarrow \bar\nu_{\mu,\tau}$ oscillations with
large mixing angles have lower best-fit values for $\Ee$ than small-mixing
angle (SMA) oscillations. Moreover, the inferred value of $\Ee$ is already in
the SMA case lower than those found in simulations. This apparent conflict has
been interpreted as evidence against the large mixing oscillation solutions to
the solar neutrino problem. In order to quantify the degree to which the
experimental data favour the SMA over the large mixing solutions we use their
likelihood ratios as well as a Kolmogorov-Smirnov test. We find within the
range of SN parameters predicted by simulations regions in which the LMA-MSW
solution is either only marginally disfavoured or favoured compared to the
SMA-MSW solution. We conclude therefore that the LMA-MSW solution is not in
conflict with the current understanding of SN physics. In contrast, the vacuum
oscillation and the LOW solutions to the solar neutrino problem can be excluded
at the $4\sigma$ level for most of the SN parameter ranges found in
simulations. Only a marginal region with low values of $\Ee$,
$<E_{\bar\nu_{\mu,\tau}}>$ and $\Eb$ is left over, in which these oscillation
solutions can be reconciled with the neutrino signal of SN 1987A.

</DOC>
<DOC>
<DOCNO> 71641 </DOCNO>
Evolution of the Yukawa coupling constants and seesaw operators in the


  The general features of the evolution of the Yukawa coupling constants and
seesaw operators in the universal seesaw model with det M_F=0 are investigated.
Especially, it is checked whether the model causes bursts of Yukawa coupling
constants, because in the model not only the magnitude of the Yukawa coupling
constant (Y_L^u)_{33} in the up-quark sector but also that of (Y_L^d)_{33} in
the down-quark sector is of the order of one, i.e., (Y_L^u)_{33} \sim
(Y_L^d)_{33} \sim 1. The requirement that the model should be calculable
perturbatively puts some constraints on the values of the intermediate mass
scales and tan\beta (in the SUSY model).

</DOC>
<DOC>
<DOCNO> 116461 </DOCNO>
Hierarchic Models of Turbulence, Superfluidity and Superconductivity


 1 Turbulence. General description; 2 Mesoscopic mechanism of turbulence; 3
Superfluidity. General description; 4 Mesoscopic scenario of fluidity; 5
Superfluidity as a hierarchic self-organization process; 6 Superfluidity in
3He; 7 Superconductivity: General properties of metals and semiconductors;
Plasma oscillations; Cyclotron resonance; Electroconductivity; 8. Microscopic
theory of superconductivity (BCS); 9. Mesoscopic scenario of superconductivity:
Interpretation of experimental data in the framework of mesoscopic model of
superconductivity.

</DOC>
<DOC>
<DOCNO> 120883 </DOCNO>
Mining the Metal-Rich Stars for Planets


  We examine the correlation between stellar metallicity and short period
planets. It appears that approximately 1% of dwarf stars in the solar
neighborhood harbor short-period planets characterized by near-circular orbits
and orbital periods P<20 days. However, among the most metal-rich stars
(defined as having [Fe/H]>0.2 dex), it appears that the fraction increases to
10%. Using the Hipparcos database and the Hauck & Mermilliod (1998) compilation
of Stromgren uvby photometry, we identify a sample of 206 metal-rich stars of
spectral type K, G, and F which have an enhanced probability of harboring
short-period planets. Many of these stars would be excellent candidates for
addition to radial velocity surveys. We have searched the Hipparcos epoch
photometry for transiting planets within our 206 star catalog. We find that the
quality of the Hipparcos data is not high enough to permit unambiguous transit
detections. It is, however, possible to identify candidate transit periods. We
then discuss various ramifications of the stellar metallicity - planet
connection. First, we show that there is preliminary evidence for increasing
metallicity with increasing stellar mass among known planet-bearing stars. This
trend can be explained by a scenario in which planet-bearing stars accrete an
average of 30 Earth Masses of rocky material after the gaseous protoplanetary
disk phase has ended. We present dynamical calculation which suggest that a
survey of metallicities of spectroscopic binary stars can be used to understand
the root cause of the stellar metallicity - planet connection.

</DOC>
<DOC>
<DOCNO> 117278 </DOCNO>
Ultracold collisions of metastable helium atoms


  We report scattering lengths for the singlet Sigma g +, triplet Sigma u + and
quintet Sigma g + adiabatic molecular potentials relevant to collisions of two
metastable (n=2 triplet S) helium atoms as a function of the uncertainty in
these potentials. These scattering lengths are used to calculate experimentally
observable scattering lengths, elastic cross sections and inelastic rates for
any combination of states of the colliding atoms, at temperatures where the
Wigner threshold approximation is valid.

</DOC>
<DOC>
<DOCNO> 11860 </DOCNO>
Liquid drop in a cone - line tension effects


  The shape of a liquid drop placed in a cone is analyzed macroscopically.
Depending on the values of the cone opening angle, the Young angle and the line
tension four different interfacial configurations may be realized. The phase
diagram in these variables is constructed and discussed; it contains both the
first- and the second-order transition lines. In particular, the tricritical
point is found and the value of the critical exponent characterizing the
behaviour of the system along the line of the first-order transitions in the
neighbourhood of this point is determined.

</DOC>
<DOC>
<DOCNO> 121121 </DOCNO>
Can a Very Low-Luminosity and Cold White Dwarf be a Self-gravitating


  An entirely new model for the structure as well as for the cooling mechanism
of white dwarfs has been proposed. We have argued that the massive part of the
constituents of white dwarfs- the positively charged ions are boson and under
the extreme physical condition (density and temperature) at the interior, it is
possible to have condensation of charged bose gas. We have tried to establish
that a cold white dwarf is a self gravitating charged bose condensed system.

</DOC>
<DOC>
<DOCNO> 151157 </DOCNO>
S^3 and S^4 Reductions of Type IIA Supergravity


  We construct a consistent reduction of type IIA supergravity on S^3, leading
to a maximal gauged supergravity in seven dimensions with the full set of
massless SO(4) Yang-Mills fields. We do this by starting with the known S^4
reduction of eleven-dimensional supergravity, and showing that it is possible
to take a singular limit of the resulting standard SO(5)-gauged maximal
supergravity in seven dimensions, whose eleven-dimensional interpretation
involves taking a limit where the internal 4-sphere degenerates to RxS^3. This
allows us to reinterpret the limiting SO(4)-gauged theory in seven dimensions
as the S^3 reduction of type IIA supergravity. We also obtain the consistent
S^4 reduction of type IIA supergravity, which gives an SO(5)-gauged maximal
supergravity in D=6.

</DOC>
<DOC>
<DOCNO> 83406 </DOCNO>
Applications of Data Mining to Electronic Commerce


  Electronic commerce is emerging as the killer domain for data mining
technology.
  The following are five desiderata for success. Seldom are they they all
present in one data mining application.
  1. Data with rich descriptions. For example, wide customer records with many
potentially useful fields allow data mining algorithms to search beyond obvious
correlations.
  2. A large volume of data. The large model spaces corresponding to rich data
demand many training instances to build reliable models.
  3. Controlled and reliable data collection. Manual data entry and integration
from legacy systems both are notoriously problematic; fully automated
collection is considerably better.
  4. The ability to evaluate results. Substantial, demonstrable return on
investment can be very convincing.
  5. Ease of integration with existing processes. Even if pilot studies show
potential benefit, deploying automated solutions to previously manual processes
is rife with pitfalls. Building a system to take advantage of the mined
knowledge can be a substantial undertaking. Furthermore, one often must deal
with social and political issues involved in the automation of a previously
manual business process.

</DOC>
<DOC>
<DOCNO> 122584 </DOCNO>
Superluminal Recession Velocities


  Hubble's Law, v=HD (recession velocity is proportional to distance), is a
theoretical result derived from the Friedmann-Robertson-Walker metric. v=HD
applies at least as far as the particle horizon and in principle for all
distances. Thus, galaxies with distances greater than D=c/H are receding from
us with velocities greater than the speed of light and superluminal recession
is a fundamental part of the general relativistic description of the expanding
universe. This apparent contradiction of special relativity (SR) is often
mistakenly remedied by converting redshift to velocity using SR. Here we show
that galaxies with recession velocities faster than the speed of light are
observable and that in all viable cosmological models, galaxies above a
redshift of three are receding superluminally.

</DOC>
<DOC>
<DOCNO> 119888 </DOCNO>
ISO observations of the Wolf-Rayet galaxy NGC 7714 and its companion


  The interacting system Arp 284 consisting of the Wolf-Rayet galaxy NGC 7714
and its irregular companion NGC 7715 was observed using the Infrared Space
Observatory. Deconvolved ISOCAM maps of the galaxies using the 14.3, 7.7 and 15
micron LW3, LW6 and LW9 filters, along with ISOPHOT spectrometry of the nuclear
region of NGC 7714 were obtained and are presented. Strong ISOCAM emission was
detected from the central source in NGC 7714, along with strong PAH features,
the emission line [Ar II], molecular hydrogen at 9.66 microns and a blend of
features including [S IV] at 10.6 microns. IR emission was not detected from
the companion galaxy NGC 7715, the bridge linking the two galaxies or from the
partial stellar ring in NGC 7714 where emission ceases abruptly at the
interface between the disk and the ring.
  The morphology of the system can be well described by an off-centre collision
between the two galaxies. The LW3/LW2, where the LW2 flux was synthesized from
the PHOT-SL spectrum, LW9/LW6 and LW3/LW6 ratios suggest that the central burst
within NGC 7714 is moving towards the post-starburst phase, in agreement with
the age of the burst. Diagnostic tools including the ratio of the integrated
PAH luminosity to the 40 to 120 microns infrared luminosity and the
far-infrared colours reveal that despite the high surface brightness of the
nucleus, the properties of NGC 7714 can be explained in terms of a starburst
and do not require the prescence an AGN.

</DOC>
<DOC>
<DOCNO> 152058 </DOCNO>
TCP in q-Lorentz Theories


  The connection between spin and statistics implied by the continuous Lorentz
group together with strong reflection (TCP) is shown to hold also for the
q-Lorentz group.

</DOC>
<DOC>
<DOCNO> 123293 </DOCNO>
An Extremely Red Nucleus in an Absorbed QSO at z=0.65


  The results of K-band-imaging observations of a candidate of an absorbed QSO
at z=0.653, AX J131831+3341, are presented. The B-K color of the object is 4.85
mag, which is much redder than optically-selected QSOs. The K-band image shows
nuclear and extended components, the same as in the optical V-, R-, and I-band
images. The nuclear component (I-K = 4.29 mag) is much redder than the
power-law models with energy indices of 0 to -1.0, which well reproduce the V-R
and R-I optical colors of the nuclear component. A heavily absorbed (A_V = 3
mag) nucleus may emerge in the K-band, while optical light may originate from
scattered nuclear light. The I-K color of the extended component is 2.2 mag,
which is consistent with the post-starburst nature of the host galaxy, which is
also suggested from the V-R and R-I colors of the extended component.

</DOC>
<DOC>
<DOCNO> 13297 </DOCNO>
Numerical analysis of the magnetic-field-tuned superconductor-insulator


  Ground state of the two-dimensional hard-core-boson model subjected to
external magnetic field and quenched random chemical potential is studied
numerically. In experiments, magnetic-field-tuned superconductor-insulator
transition has already come under through investigation, whereas in computer
simulation, only randomness-driven localization (with zero magnetic field) has
been studied so far: The external magnetic field brings about a difficulty that
the hopping amplitude becomes complex number (through the gauge twist), for
which the quantum Monte-Carlo simulation fails. Here, we employ the exact
diagonalization method, with which we demonstrate that the model does exhibit
field-tuned localization transition at a certain critical magnetic field. At
the critical point, we found that the DC conductivity is not universal, but is
substantially larger than that of the randomness-driven localization transition
at zero magnetic field. Our result supports recent experiment by Markovi'c et
al. reporting an increase of the critical conductivity with magnetic field
strengthened.

</DOC>
<DOC>
<DOCNO> 122372 </DOCNO>
AGN in the XMM-Newton first-light image as probes for the interstellar


  The XMM-Newton first-light image revealed X-ray point sources which show
heavily absorbed power-law spectra. The spectral indices and the probable
identification of a radio counterpart for the brightest source suggest AGN
shining through the interstellar gas of the Large Magellanic Cloud (LMC). The
column densities derived from the X-ray spectra in combination with HI
measurements will allow to draw conclusions on HI to H_2 ratios in the LMC and
compare these with values found for the galactic plane.

</DOC>
<DOC>
<DOCNO> 9394 </DOCNO>
The patching of critical points using quantum group


  Following our recent conjecture to model the phenomenona of
antiferromagnetism and superconductivity by quantum symmetry groups, we discuss
in the present note how to construct a workable scenario using this symmetry.
In particular we propose to patch the relevant critical points. This means we
identify fixed points, corresponding to various $k$ or $q$ [since the two are
related] and make expansion around these points, to control these expansion we
can impose gauge structure and we thus arrive at quantum group based gauge
theory or collection of classical gauge theories which represent the condensed
matter system such as cuprates. This is different than ordinary gauge theories
in several ways, for in ordinary field theory one has well-defined critical
point here the critical points are not unique or simple. In short the real
transition than in condensed matter system is represented by collection or {\it
ensemble average} of the several chosen critical points which come from
ordinary field theory [gauge theory].
  This idea may reveal the connection between Hubbard model and gauge theory
and string theory.
  In short it can lead to the non-perturbative formualtion of Hubbard and other
condensed matter Hamiltonians.

</DOC>
<DOC>
<DOCNO> 117372 </DOCNO>
The 24-Hour Night Shift: Astronomy from Microlensing Monitoring Networks


  Scores of on-going microlensing events are now announced yearly by the
microlensing discovery teams OGLE, MACHO and EROS. These early warning systems
have allowed other international microlensing networks to focus considerable
resources on intense photometric - and occasionally spectroscopic - monitoring
of microlensing events. Early results include: metallicity measurements of main
sequence Galactic bulge stars; limb darkening determinations for stars in the
Bulge and Small Magellanic Cloud; proper motion measurements that constrain
microlens identity; and constraints on Jovian-mass planets orbiting (presumably
stellar) lenses. These results and auxiliary science such as variable star
studies and optical identification of gamma ray bursts are reviewed.

</DOC>
<DOC>
<DOCNO> 40305 </DOCNO>
Measurements of the parameters of the $\phi(1020)$ resonance through


  The cross sections of the processes $e^+e^- \to K^+K^-$, $e^+e^- \to K_SK_L$
and $e^+e^- \to \pi^+\pi^-\pi^0$ were measured in the SND experiment at the
VEPP-2M collider in the energy region near the $\phi(1020)$ meson. These
measurements were based on about $10^6$ $K^+K^-$, $0.5 \times 10^6$ $K_SK_L$
and $0.4 \times 10^6$ $\pi^+\pi^-\pi^0$ selected events. Themeasured cross
sections have been analyzed in the framework of the vector meson dominance
model and the main parameters of the $\phi$-resonance were obtained, such as
its mass, width, the production cross section and branching ratios of the main
decay modes. The measured value of the $\phi$ meson total width, $\Gamma_{\phi}
= 4.21 \pm 0.04$ is lower than the present world average of $4.458 \pm 0.032$
MeV. Contributions in addition to the conventional vector meson dominance model
were found in the $e^+e^- \to \pi^+\pi^-\pi^0$ reaction cross section.

</DOC>
<DOC>
<DOCNO> 10616 </DOCNO>
Thermalization of Quantum Fields from Time-Reversal Invariant Evolution


  We study the time evolution of correlation functions in closed quantum
systems for nonequilibrium ensembles of initial conditions. For a scalar
quantum field theory we show that generic time-reversal invariant evolutions
approach equilibrium at large times. The calculation provides a first
principles justification of Boltzmann's conjecture that the large-time behavior
of isolated macroscopic systems can be described by thermal ensemble averages.

</DOC>
<DOC>
<DOCNO> 9295 </DOCNO>
Magnetic Field Effects on Neutron Diffraction in the Antiferromagnetic


  We discuss possible magnetic structures in UPt$_3$ based on our analysis of
elastic neutron-scattering experiments in high magnetic fields at temperatures
$T<T_N$. The existing experimental data can be explained by a single-{\bf q}
antiferromagnetic structure with three independent domains. For modest in-plane
spin-orbit interactions, the Zeeman coupling between the antiferromagnetic
order parameter and the magnetic field induces a rotation of the magnetic
moments, but not an adjustment of the propagation vector of the magnetic order.
A triple-{\bf q} magnetic structure is also consistent with neutron
experiments, but in general leads to a non-uniform magnetization in the
crystal. New experiments could decide between these structures.

</DOC>
<DOC>
<DOCNO> 67972 </DOCNO>
Partially Quenched Chiral Condensates from the Replica Method


  A large-N_f expansion is used to compute the partially quenched chiral
condensate of QCD in the microscopic finite-volume scaling region.

</DOC>
<DOC>
<DOCNO> 8839 </DOCNO>
Comment on "Quantum diffusion of 3-He impurities in solid 4- He"


  In this comment I show that the experimental data on quantum diffusion of
3-He impurities in solid 4-He can be explained using the adopted quasiparticle
theory. The contention by E.G. Kisvarsanyi and N.S. Sullivan (KS) in Phys.Rev.B
v. 48, 16557 (1993) as well as in their Reply (ibid. v. 55, 3989 (1997)) to the
Grigor'ev's Comment (Phys.Rev. B v. 55, 3987 (1997)) that "Pushkarov's theory
of phonon scattering fails to fit the data by very large factors" is groundless
and may result from their bad arithmetical error. This means that the
phonon-impurity scattering mechanism of diffusion is consistent with experiment
and its neglecting by KS makes their results questionable.

</DOC>
<DOC>
<DOCNO> 85488 </DOCNO>
On generalizations of the spectrum condition


  It is well known that the spectrum condition, i.e. the positivity of the
energy in every inertial coordinate system, is one of the central conceptual
ingredients in model-independent approaches to relativistic quantum field
theory. When one attempts to formulate quantum field theory in a
model-independent manner on a curved background spacetime, it is not
immediately clear which concepts replace the spectrum condition. The present
work is devoted to reviewing facets of this situation, thereby focussing on one
particular approach that attempts to generalize the notion of energy-momentum
spectrum by the notion of "wavefront set", which may be seen as an asymptotic
high-frequency part of the spectrum.

</DOC>
<DOC>
<DOCNO> 169985 </DOCNO>
Optimal N-to-M Cloning of Quantum Coherent States


  The cloning of continuous quantum variables is analyzed based on the concept
of Gaussian cloning machines, i.e., transformations that yield copies that are
Gaussian mixtures centered on the state to be copied. The optimality of
Gaussian cloning machines that transform N identical input states into M output
states is investigated, and bounds on the fidelity of the process are derived
via a connection with quantum estimation theory. In particular, the optimal
N-to-M cloning fidelity for coherent states is found to be equal to
MN/(MN+M-N).

</DOC>
<DOC>
<DOCNO> 100460 </DOCNO>
Reflection symmetries of almost periodic functions


  We study global reflection symmetries of almost periodic functions. In the
non-limit periodic case, we establish an upper bound on the Haar measure of the
set of those elements in the hull which are almost symmetric about the origin.
As an application of this result we prove that in the non-limit periodic case,
the criterion of Jitomirskaya and Simon ensuring absence of eigenvalues for
almost periodic Schr\"odinger operators is only applicable on a set of zero
Haar measure. We complement this by giving examples of limit periodic functions
where the Jitomirskaya-Simon criterion can be applied to every element of the
hull.

</DOC>
<DOC>
<DOCNO> 122370 </DOCNO>
Models of Polarized and Variable Radio Emission for IDV Source 0917+624


  We examine the power spectra of IDV and show the information, which is to be
gained by wavelet analysis of light curves of the quasar 0917+624. Results for
total and polarized flux at 11cm are shown. Both interstellar scattering and
intrinsic models have difficulties in explaining the 1 day period variations. A
theoretical model for the time averaged emission is presented, which provides
the basis for the analysis of possible variations.

</DOC>
<DOC>
<DOCNO> 84183 </DOCNO>
Quantum Coherent String States in AdS_3 and SL(2,R) WZWN Model


  In this paper we make the connection between semi-classical string
quantization and exact conformal field theory quantization of strings in 2+1
Anti de Sitter spacetime. More precisely, considering the WZWN model
corresponding to SL(2,R) and its covering group, we construct quantum {\it
coherent} string states, which generalize the ordinary coherent states of
quantum mechanics, and show that in the classical limit they correspond to
oscillating circular strings. After quantization, the spectrum is found to
consist of two parts: A continuous spectrum of low mass states (partly
tachyonic) fulfilling the standard spin-level condition necessary for unitarity
|j|< k/2, and a discrete spectrum of high mass states with asymptotic behaviour
m^2\alpha'\propto N^2 (N positive integer). The quantization condition for the
high mass states arises from the condition of finite positive norm of the
coherent string states, and the result agrees with our previous results
obtained using semi-classical quantization. In the k\to\infty limit, all the
usual properties of coherent or {\it quasi-classical} states are recovered. It
should be stressed that we consider the circular strings only for simplicity
and clarity, and that our construction can easily be used for other string
configurations too. We also compare our results with those obtained in the
recent preprint hep-th/0001053 by Maldacena and Ooguri.

</DOC>
<DOC>
<DOCNO> 69810 </DOCNO>
The Gluon Spin in the Chiral Bag Model


  We study the gluon polarization contribution at the quark model
renormalization scale to the proton spin, $\Gamma$, in the chiral bag model. It
is evaluated by taking the expectation value of the forward matrix element of a
local gluon operator in the axial gauge $A^+=0$. It is shown that the confining
boundary condition for the color electric field plays an important role. When a
solution satisfying the boundary condition for the color electric field, which
is not the conventionally used but which we favor, is used, the $\Gamma$ has a
positive value for {\it all} bag radii and its magnitude is comparable to the
quark spin polarization. This results in a significant reduction in the
relative fraction of the proton spin carried by the quark spin, which is
consistent with the small flavor singlet axial current measured in the EMC
experiments.

</DOC>
<DOC>
<DOCNO> 68412 </DOCNO>
Charge-odd and single-spin effects in two-pion production in ep


  We consider double-photon and bremsstrahlung mechanisms for the production of
two charged pions in high-energy electron (or proton) scattering off a
transversely polarised proton. Interference between the relevant amplitudes
generates a charge-odd contribution to the cross-section for the process. In
the kinematical configuration with a jet nearly collinear to the electron, the
spin-independent part may be used to the determine phase differences for
pion-pion scattering in states with orbital momentum 0 or 2 and 1, while for
the configuration with a jet nearly collinear to the proton, the spin-dependent
part may be used to explain the experimental data for single-spin correlations
in the production of negatively charged pions. We also discuss the backgrounds
and estimate the accuracy of the results to be better than 10 %. In addition,
simplified formulae derived for specific kinematics, with small total
transverse pion momenta, are given. The accuracy is estimated to remain at the
same level despite the lower energy.

</DOC>
<DOC>
<DOCNO> 100056 </DOCNO>
Courbes rationnelles sur les vari\'et\'es homog\`enes et une


  In this article we prove the irreducibility of the Hilbert scheme of
rationnal curves on homogeneous varieties with fixed class in the Chow ring.
This result has also been proved by J. F. Thomsen [T] and B. Kim and R.
Pandharipande [KP]. Our method is totaly different (we don't use the
compactification of stable maps) and enables us to prove the existence of
rational smooth curves on homogeneous varities with fixed class in the Chow
ring. This was not the case of Thomsen's and Kim and Pandharipande's proofs. We
use a decomposition of G/P in orbits (called the P'-orbits, see definition)
which are bigger than the Schubert cells. We then prove that these P'-orbits
are "towers" of affine bundles (see definition) over "smaller" homogeneous
varities. This description gives the results. Our decomposition in P'-orbits
enables us to give a "better" desingularisation of Schubert varities than
Demazure's one.

</DOC>
<DOC>
<DOCNO> 68496 </DOCNO>
Conformal Phase Transition, beta-Function, and Infrared Dynamics in QCD


  The dynamics in QCD with different number of fermion flavors N_f is
discussed. The emphasis is on the description of the conformal phase transition
with respect to N_f separating a phase with no confinement and chiral symmetry
breaking and a phase with confinement and with chiral symmetry breaking.

</DOC>
<DOC>
<DOCNO> 117788 </DOCNO>
A High Sensitivity Measurement of the MeV Gamma-Ray Spectrum of Cygnus


  The Compton Gamma-Ray Observatory (CGRO) has observed the Cygnus region on
several occasions since its launch in 1991. The data collected by the COMPTEL
experiment on CGRO represent the most sensitive observations to date of Cygnus
X-1 in the 0.75-30 MeV range. A spectrum accumulated by COMPTEL over 10 weeks
of observation time shows significant evidence for emission extending out to
several MeV. We have combined these data with contemporaneous data from both
BATSE and OSSE to produce a broad-band gamma-ray spectrum, corresponding to the
low X-ray state of Cygnus X-1, extending from 50 keV up to approximately 5 MeV.
Although there is no evidence for any broad line-like emissions in the MeV
region, these data further confirm the presence of a hard tail at energies
above several hundred keV. In particular, the spectrum at MeV energies can be
described as a power-law with a photon spectral index of $\alpha$ = -3.2, with
no evidence for a cutoff at high energies. For the 200 keV to 5 MeV spectrum,
we provide a quantitative description of the underlying electron spectrum, in
the context of a hybrid thermal/non-thermal model for the emission. The
electron spectrum can be described by a thermal Maxwellian with a temperature
of $kT_e$ = 86 keV and a non-thermal power-law component with a spectral index
of $p_e$ = 4.5. The spectral data presented here should provide a useful basis
for further theoretical modeling.

</DOC>
<DOC>
<DOCNO> 117082 </DOCNO>
Relativistic Geometry and Weak Interactions


  Geometric interactions in a new relativistic geometric unified theory include
interactions other than gravitation and electromagnetism. In a low energy limit
one of these interactions leads essentially to a Fermi type theory of weak
interactions including the Hamiltonian and coupling constant.

</DOC>
<DOC>
<DOCNO> 12735 </DOCNO>
Transport through Quantum Dots: Analytic Results from Integrability


  Recent experiments have probed quantum dots through transport measurements in
the regime where they are described by a two lead Anderson model. In this paper
we develop a new method to analytically compute for the first time the
corresponding transport properties. This is done by using the exact solvability
of the Anderson Hamiltonian, together with a generalization of the
Landauer-Buttiker approach to integrable systems. The latter requires proper
identification of scattering states, a complex and crucial step in our
approach. In the Kondo regime, our results include the zero-field, finite
temperature linear response conductance, as well as the zero-temperature,
non-equilibrium conductance in an applied Zeeman field.

</DOC>
<DOC>
<DOCNO> 12242 </DOCNO>
Electronic Ladders with SO(5) Symmetry: Phase Diagrams and Correlations


  We construct a family of electronic ladder models with SO(5) symmetry which
have exact ground states in the form of finitely correlated wave functions.
Extensions for these models preserving this symmetry are studied using these
states in a variational approach. Within this approach, the zero temperature
phase diagram of these electronic ladders at half filling is obtained,
reproducing the known results in the weak coupling (band insulator) and strong
coupling regime, first studied by Scalapino, Zhang and Hanke. Finally, the
compact form of the variational wave functions allows to compute various
correlation functions for these systems.

</DOC>
<DOC>
<DOCNO> 150872 </DOCNO>
Vertex Operators for the Supermembrane


  We derive the vertex operators that are expected to govern the emission of
the massless d=11 supermultiplet from the supermembrane in the light cone
gauge. We demonstrate that they form a representation of the supersymmetry
algebra and reduce to the type IIA superstring vertex operators under double
dimensional reduction, as well as to the vertices of the d=11 superparticle in
the point-particle limit. As a byproduct, our results can be used to derive the
corresponding vertex operators for matrix theory and to describe its linear
coupling to an arbitrary d=11 supergravity background. Possible applications
are discussed.

</DOC>
<DOC>
<DOCNO> 11574 </DOCNO>
Statistical Properties of Share Volume Traded in Financial Markets


  We quantitatively investigate the ideas behind the often-expressed adage `it
takes volume to move stock prices', and study the statistical properties of the
number of shares traded $Q_{\Delta t}$ for a given stock in a fixed time
interval $\Delta t$. We analyze transaction data for the largest 1000 stocks
for the two-year period 1994-95, using a database that records every
transaction for all securities in three major US stock markets. We find that
the distribution $P(Q_{\Delta t})$ displays a power-law decay, and that the
time correlations in $Q_{\Delta t}$ display long-range persistence. Further, we
investigate the relation between $Q_{\Delta t}$ and the number of transactions
$N_{\Delta t}$ in a time interval $\Delta t$, and find that the long-range
correlations in $Q_{\Delta t}$ are largely due to those of $N_{\Delta t}$. Our
results are consistent with the interpretation that the large equal-time
correlation previously found between $Q_{\Delta t}$ and the absolute value of
price change $| G_{\Delta t} |$ (related to volatility) are largely due to
$N_{\Delta t}$.

</DOC>
<DOC>
<DOCNO> 40557 </DOCNO>
Measurement of Delta-md Using a Probability Based Same-Side Tagger at


  A measurement of Delta m_d is performed using inclusive lepton+vertex events
at CDF. A probability based Same-Side Tagger was developed to tag the initial
b-flavor of the B^0_d, which suppresses tagging on B-decay products. We find
Delta m_d = 0.42 +/- 0.09 +/- 0.03 ps^-1.

</DOC>
<DOC>
<DOCNO> 118893 </DOCNO>
Can our Universe be inhomogeneous on large sub-horizon scales ?


  We show that our Universe may be inhomogeneous on large sub-horizon scales
without us being able to realise it. We assume that a network of domain walls
permeates the universe dividing it in domains with slightly different vacuum
energy densities. We require that the energy scale of the phase transition
which produced the domain walls is sufficiently low so that the walls have a
negligible effect on structure formation. Nevertheless, the different vacuum
densities of different domains will lead to different values of the
cosmological parameters $\Omega_\Lambda^0$, $\Omega_m^0$ and $h$, in each patch
thus affecting the growth of cosmological perturbations at recent times. Hence,
if our local patch of the universe (with uniform vacuum density) is big enough
-- which is likely to happen given that we should have on average about one
domain per horizon volume -- we might not notice these large-scale
inhomogeneities. This happens because in order to see a patch with a different
vacuum density one may have to look back at a time when the universe was still
very homogeneous.

</DOC>
<DOC>
<DOCNO> 70736 </DOCNO>
Chiral Meson Masses at Finite Temperature and Density


  The ratio of the sigma mass to the pion mass at finite temperatures and
densities provides for a quantitative signal of chiral symmetry breaking. We
calculate this ratio by using an extension to finite chemical potential of the
field theoretic composite operator formalism as applied to QCD. The calculation
is limited to regions of the phase diagram where only quark-antiquark
condensates dominate (no quark-quark condensates) and it confirms the expected
behaviours. In particular the sigma becomes an essentially stable particle in a
narrow region bordering the transition line from broken to restored chirality .
This pattern is qualitatively the same both for the region where the transition
is of second order as for the region where it is of first order (apart from the
discontinuities expected in the latter case).

</DOC>
<DOC>
<DOCNO> 99987 </DOCNO>
Taut ideal triangulations of 3-manifolds


  A taut ideal triangulation of a 3-manifold is a topological ideal
triangulation with extra combinatorial structure: a choice of transverse
orientation on each ideal 2-simplex, satisfying two simple conditions. The aim
of this paper is to demonstrate that taut ideal triangulations are very common,
and that their behaviour is very similar to that of a taut foliation. For
example, by studying normal surfaces in taut ideal triangulations, we give a
new proof of Gabai's result that the singular genus of a knot in the 3-sphere
is equal to its genus.

</DOC>
<DOC>
<DOCNO> 68562 </DOCNO>
Polarized Photoproduction of Heavy Quarks in Next-to-Leading Order


  The results of a next-to-leading order calculation of heavy quark production
in longitudinally polarized photon-nucleon collisions are presented. At c.m.
energy $\sqrt{S}=10$ GeV, for $\vec \gamma +\vec p \to c+X$, cross sections
differential in the transverse momentum and rapidity of the charmed quark $c$
and the corresponding asymmetries are presented; also, as functions of
$\sqrt{S}$, integrated cross sections, $K$-factors and the corresponding
asymmetries are given. Errors in the asymmetries are estimated and the
possibility to distinguish between three scerarios differing essentially in the
polarized gluon distribution is discussed.

</DOC>
<DOC>
<DOCNO> 11995 </DOCNO>
Experimental study of negative photoconductivity in n-PbTe(Ga) epitaxial


  We report on low-temperature photoconductivity (PC) in n-PbTe(Ga) epitaxial
films prepared by the hot-wall technique on <111>-BaF_2 substrates. Variation
of the substrate temperature allowed us to change the resistivity of the films
from 10^8 down to 10_{-2} Ohm x cm at 4.2 K. The resistivity reduction is
associated with a slight excess of Ga concentration, disturbing the Fermi level
pinning within the energy gap of n-PbTe(Ga). PC has been measured under
continuous and pulse illumination in the temperature range 4.2-300 K. For films
of low resistivity, the photoresponse is composed of negative and positive
parts. Recombination processes for both effects are characterized by
nonexponential kinetics depending on the illumination pulse duration and
intensity. Analysis of the PC transient proves that the negative
photoconductivity cannot be explained in terms of nonequilibrium charge
carriers spatial separation of due to band modulation. Experimental results are
interpreted assuming the mixed valence of Ga in lead telluride and the
formation of centers with a negative correlation energy. Specifics of the PC
process is determined by the energy levels attributed to donor Ga III, acceptor
Ga I, and neutral Ga II states with respect to the crystal surrounding. The
energy level corresponding to the metastable state Ga II is supposed to occur
above the conduction band bottom, providing fast recombination rates for the
negative PC. The superposition of negative and positive PC is considered to be
dependent on the ratio of the densities of states corresponding to the donor
and acceptor impurity centers.

</DOC>
<DOC>
<DOCNO> 13676 </DOCNO>
Ground state non-universality in the random field Ising model


  Two attractive and often used ideas, namely universality and the concept of a
zero temperature fixed point, are violated in the infinite-range random-field
Ising model. In the ground state we show that the exponents can depend
continuously on the disorder and so are non-universal. However, we also show
that at finite temperature the thermal order parameter exponent one half is
restored so that temperature is a relevant variable. The broader implications
of these results are discussed.

</DOC>
<DOC>
<DOCNO> 102230 </DOCNO>
End compactifications in non-locally-finite graphs


  There are different definitions of ends in non-locally-finite graphs which
are all equivalent in the locally finite case. We prove the compactness of the
end-topology that is based on the principle of removing finite sets of vertices
and give a proof of the compactness of the end-topology that is constructed by
the principle of removing finite sets of edges. For the latter case there
exists already a proof in \cite{cartwright93martin}, which only works on graphs
with countably infinite vertex sets and in contrast to which we do not use the
Theorem of Tychonoff. We also construct a new topology of ends that arises from
the principle of removing sets of vertices with finite diameter and give
applications that underline the advantages of this new definition.

</DOC>
<DOC>
<DOCNO> 13137 </DOCNO>
Large N limit of Calogero-Moser models and Conformal Field Theories


  We discuss the large N limit of Calogero-Moser models for the classical
infinite families of simple Lie algebras A_N, B_N, C_N and D_N. We show that
the limit defines two different Conformal Field Theories with central charge
c>1. The value of c and the dimension of the primary field are dictated by the
underlying algebraic symmetries of the model.

</DOC>
<DOC>
<DOCNO> 71927 </DOCNO>
Parton showers and multijet events


  A Monte-Carlo event-generator has been developed which is dedicated to
simulate electron-positron annihilations. Especially a new approach for the
combination of matrix elements and parton showers ensures the independence of
the hadronization parameters from the CMS energy. This enables for the first
time the description of multijet-topologies, e.g. four jet angles, over a wide
range of energy, without changing any parameter of the model. Covering all
processes of the standard model our simulator is capable to describe
experiments at present and future accelerators, i.e. the LEP collider and a
possible Next Linear Collider(NLC).

</DOC>
<DOC>
<DOCNO> 84378 </DOCNO>
Gravitational conformal invariance and coupling constants in


  We introduce a generalized gravitational conformal invariance in the context
of non-compactified 5D Kaluza-Klein theory. It is done by assuming the 4D
metric to be dependent on the extra non-compactified dimension. It is then
shown that the conformal invariance in 5D is broken by taking an absolute
cosmological scale $R_0$ over which the 4D metric is assumed to be dependent
weakly on the 5th dimension. This is equivalent to Deser's model for the
breakdown of the conformal invariance in 4D by taking a constant cosmological
mass term $\mu^2\sim R_0^{-2}$ in the theory. We set the scalar field to its
background cosmological value leading to Einstein equation with the
gravitational constant $G_N$ and a small cosmological constant. A dual Einstein
equation is also introduced in which the matter is coupled to the higher
dimensional geometry by the coupling $G_N^{-1}$. Relevant interpretations of
the results are also discussed.

</DOC>
<DOC>
<DOCNO> 84558 </DOCNO>
On the Mass Neutrino Phase calculations along the geodesic line and the


  On the mass neutrino phase calculations along both the particle geodesic line
and the photon null line, there exists a double counting error---factor of 2
when comparing the geodesic phase with the null phase. For the mass neutrino
propagation in the flat spacetime, we study the neutrino interference phase
calculation in the Minkowski diagram and find that the double counting effect
originates from despising the velocity difference between two mass neutrinos.
Moreover, we compare the phase calculations among the same energy description,
the same momentum description and same velocity description by means of the
Minkowski diagram, and obtain the practical equivalence of these three
descriptions. Further, in the curved spacetime, we also prove the existence of
the double counting of the geodesic phase to the null phase.

</DOC>
<DOC>
<DOCNO> 9891 </DOCNO>
Spinodal Decomposition and the Tomita Sum Rule


  The scaling properties of a phase-ordering system with a conserved order
parameter are studied. The theory developed leads to scaling functions
satisfying certain general properties including the Tomita sum rule. The theory
also gives good agreement with numerical results for the order parameter
scaling function in three dimensions. The values of the associated
nonequilibrium decay exponents are given by the known lower bounds.

</DOC>
<DOC>
<DOCNO> 121064 </DOCNO>
A Magnetic Dynamo Origin For The Sub-mm Excess In Sgr A*


  The sub-mm bump observed in the spectrum of Sgr A* appears to indicate the
existence of a compact emitting component within several Schwarzschild radii,
$r_S$, of the nucleus at the Galactic Center. This is interesting in view of
the predicted circularized flow within $\sim 5-10 r_S$, based on detailed
multi-dimensional hydrodynamic simulations of Bondi-Hoyle accretion onto this
unusual object. In this paper, we examine the physics of magnetic field
generation by a Keplerian dynamo subject to the conditions pertaining to Sgr
A*, and show that the sub-mm bump can be produced by thermal synchrotron
emission in this inner region. This spectral feature may therefore be taken as
indirect evidence for the existence of this circularization. In addition, the
self-Comptonization of the sub-mm bump appears to produce an X-ray flux
exceeding that due to bremsstrahlung from this region, which may account for
the X-ray counterpart to Sgr A* discovered recently by {\it Chandra}. However,
the required accretion rate in the Keplerian flow is orders of magnitude
smaller than that predicted by the Bondi-Hoyle simulations. We speculate that
rapid evaporation, in the form of a wind, may ensue from the heating associated
with turbulent mixing of gas elements with large eccentricity as they settle
down into a more or less circular (i.e., low eccentricity) trajectory. The
spectrum of Sgr A* longward of $\sim 1-2$ mm may be generated outside of the
Keplerian flow, where the gas is making a transition from a quasi-spherical
infall into a circularized pattern.

</DOC>
<DOC>
<DOCNO> 151132 </DOCNO>
K-Theory Torsion


  The Chern isomorphism determines the free part of the K-groups from ordinary
cohomology. Thus to really understand the implications of K-theory for physics
one must look at manifolds with K-torsion. Unfortunately there are not many
explicit examples, and usually for very symmetric spaces. Cartesian products of
RP^n are examples where the order of the torsion part differs between K-theory
and ordinary cohomology. The dimension of corresponding branes is also
discussed. An example for a Calabi-Yau manifold with K-torsion is given.

</DOC>
<DOC>
<DOCNO> 70477 </DOCNO>
QCD Factorization For B Decays To Two Light Pseudoscalars Including


  Since b quark mass is not asymptotically large, chirally enhanced corrections
which arise from twist-3 wave functions may be important in B decays. We thus
evaluate the hadronic matrix elements with the emitted meson described by
leading twist and twist-3 distribution amplitudes $\Phi_p(x)$. After summing
over the four "vertex correction" diagrams, we obtain the results with infrared
finiteness which shows that chirally enhanced corrections arise from
$\Phi_p(x)$ can be consistently included in QCD factorization. We also briefly
discuss the contributions from "hard spectator" diagrams.

</DOC>
<DOC>
<DOCNO> 13680 </DOCNO>
Asymptotics of skew orthogonal polynomials


  Exact integral expressions of the skew orthogonal polynomials involved in
Orthogonal (beta=1) and Symplectic (beta=4) random matrix ensembles are
obtained: the (even rank) skew orthogonal polynomials are average
characteristic polynomials of random matrices. From there, asymptotics of the
skew orthogonal polynomials are derived.

</DOC>
<DOC>
<DOCNO> 39780 </DOCNO>
Transverse and Longitudinal Bose Einstein Correlations in hadronic Z0


  Bose-Einstein correlations in pairs of identical charged pions produced in a
sample of 4.3 million Z0 hadronic decays are studied as a function of the three
components of the momentum difference, transverse ("out" and "side") and
longitudinal with respect to the thrust direction of the event. A significant
difference between the transverse, r_t_side, and longitudinal, r_l, dimensions
is observed, indicating that the emitting source of identical pions, as
observed in the Longitudinally CoMoving System, has an elongated shape. This is
observed with a variety of selection techniques. Specifically, the values of
the parameters obtained by fitting the extended Goldhaber parametrisation to
the correlation function C'= C^{DATA}}/C^{MC} for two-jet events, selected with
the Durham algorithm and resolution parameter ycut=0.04, are
r_t_out=(0.647+-0.011(stat})+0.022-0.124(syst)) fm,
r_t_side=(0.809+-0.009(stat)+0.019-0.032}(syst)) fm,
r_l=(0.989+-0.011(stat)+0.030-0.015(syst})) fm and
r_l/r_t_side=1.222+-0.027(stat})+0.075-0.012(syst). The results are discussed
in the context of a recent model of Bose-Einstein correlations based on string
fragmentation.

</DOC>
<DOC>
<DOCNO> 101148 </DOCNO>
Integrable and Weyl modules for quantum affine sl_2


  We study the universal integrable modules W_q(m) of level zero for quantum
affine sl_2 and a family of maximal finite--dimensional quotients of these
modules. We show that these all have dimension 2^m. Using this, we are able to
realize W_q(m) as the space of invariants of a reprsentation of the Hecke
algebra H_m. We also give a conjecture in the general case.

</DOC>
<DOC>
<DOCNO> 121805 </DOCNO>
Correlated Sub-mm and X-ray Variability in Sgr A*


  The recent detection of Sgr A* in the X-ray band, together with the radio
polarization measurements conducted over the past few years, offer the best
constraints yet for understanding the nature of the emitting gas within several
Schwarzschild radii ($r_S$) of this supermassive black hole candidate at the
Galactic Center. Earlier, we showed that the sub-mm radiation from this source
may be associated with thermal synchrotron emission from an inner Keplerian
region within the circularization radius of the accreting plasma. In this
paper, we extend this analysis in a very important way, by calculating the
implied high-energy emission of Sgr A* associated with the orbiting, hot,
magnetized gas. We find that for the accretion rate inferred from the fits to
the sub-mm data, the dominant contribution to Sgr A*'s X-ray flux is due to
self-Comptonization of the radio photons, rather than from bremsstrahlung. The
latter is a two-body process, which would produce significant X-ray emission
only at much higher accretion rates. This picture leads to the testable
prediction that the physical conditions within the inner $\sim5r_S$ are
variable on a time scale of order a year. In particular, the accretion rate
$\dot M$ appears to have changed by about 15% between the sub-mm measurements
in 1996 and 1999. Given that the radio and self-Comptonized fluxes are strongly
correlated in this picture, the upcoming second generation Chandra observations
of Sgr A* may provide the direct evidence required to test this model.

</DOC>
<DOC>
<DOCNO> 13772 </DOCNO>
Paired and Stripe States in the Quantum Hall System


  We study a paired state at the half-filled Landau level using a mean field
theory on the von Neumann lattice. We obtain a microscopic model which shows a
continuous transition from the compressible stripe state to the paired state.
The energy gap in the paired state is calculated numerically at the half-filled
second Landau level.

</DOC>
<DOC>
<DOCNO> 101773 </DOCNO>
The Nash Conjecture for Nonprojective Threefolds


  We prove that for every compact, connected, differentiable 3--manifold $M$
there is a compact complex manifold $X$ which can be obtained from projective
3--space by a sequence of smooth, real blow ups and downs such that
 $M$ is diffeomorphic to the set of real points of $X$. By earlier results,
such an $X$ can almost never be projective.

</DOC>
<DOC>
<DOCNO> 119104 </DOCNO>
Optical imaging and spectroscopy of BL Lac objects


  We present optical images and spectroscopy for a dozen of BL Lac objects.
Most of these objects were not previously studied and we give for the first
time the properties of their host galaxies. The properties of the new host
galaxies are generally consistent with those derived in previous optical
studies. We found a case (1101-23) where the external isophotes of the galaxy
are clearly boxy.
  In addition we gathered spectroscopy for several BL Lac objects with unknown
redshift and for companion galaxies. This allowed us to derive a tentative
redshift for two new BL Lacs and to investigate the environment around PKS
0829+04. These data complement existing data available in the literature on
host galaxies of BL Lacs and their (close) environments.

</DOC>
<DOC>
<DOCNO> 7886 </DOCNO>
Center-of-Mass Properties of the Exciton in Quantum Wells


  We present high-quality numerical calculations of the exciton center-of-mass
dispersion for GaAs/AlGaAs quantum wells of widths in the range 2-20 nm. The
k.p-coupling of the heavy- and light-hole bands is fully taken into account. An
optimized center-of-mass transformation enhances numerical convergence. We
derive an easy-to-use semi-analytical expression for the exciton groundstate
mass from an ansatz for the exciton wavefunction at finite momentum. It is
checked against the numerical results and found to give very good results. We
also show multiband calculations of the exciton groundstate dispersion using a
finite-differences scheme in real space, which can be applied to rather general
heterostructures.

</DOC>
<DOC>
<DOCNO> 12707 </DOCNO>
Jacobson generators, Fock representations and statistics of sl(n+1)


  The properties of A-statistics, related to the class of simple Lie algebras
sl(n+1) (Palev, T.D.: Preprint JINR E17-10550 (1977); hep-th/9705032), are
further investigated. The description of each sl(n+1) is carried out via
generators and their relations, first introduced by Jacobson. The related Fock
spaces W_p (p=1,2,...) are finite-dimensional irreducible sl(n+1)-modules. The
Pauli principle of the underlying statistics is formulated. In addition the
paper contains the following new results: (a) The A-statistics are interpreted
as exclusion statistics; (b) Within each W_p operators B(p)_1^\pm, ...,
B(p)_n^\pm, proportional to the Jacobson generators, are introduced. It is
proved that in an appropriate topology the limit of B(p)_i^\pm for p going to
infinity is equal to B_i^\pm, where B_i^\pm are Bose creation and annihilation
operators; (c) It is shown that the local statistics of the degenerated
hard-core Bose models and of the related Heisenberg spin models is p=1
A-statistics.

</DOC>
<DOC>
<DOCNO> 117464 </DOCNO>
X-ray Measurements of the Gravitational Potential Profile in the Central


  X-ray spectral and imaging data from ASCA and ROSAT were used to measure the
total mass profile in the central region of Abell 1060, a nearby and relatively
poor cluster of galaxies. The ASCA X-ray spectra, after correcting for the
spatial response of the X-ray telescope, show an isothermal distribution of the
intra-cluster medium (ICM) within at least $\sim$ 12' (or $160h_{70}^{-1}$ kpc;
$H_0 = 70 h_{70}$ km s$^{-1}$Mpc$^{-1}$) in radius of the cluster center. The
azimuthally averaged surface brightness profile from the ROSAT PSPC exhibits a
central excess above an isothermal $\beta$ model. The ring-sorted ASCA GIS
spectra and the radial surface brightness distribution from the ROSAT PSPC were
simultaneously utilized to constrain the gravitational potential profile. Some
analytic models of the total mass density profile were examined. The ICM
density profile was also specified by analytic forms. The ICM temperature
distribution was constrained to satisfy the hydrostatic equilibrium, and to be
consistent with the data. Then, the total mass distribution was found to be
described better by the universal dark halo profile proposed by Navarro, Frenk,
and White (1996;1997) than by a King-type model with a flat density core. A
profile with a central cusp together with a logarithmic radial slope of $\sim
1.5$ was also consistent with the data. Discussions are made concerning the
estimated dark matter distribution around the cluster center.

</DOC>
<DOC>
<DOCNO> 83230 </DOCNO>
Axiomatizing Causal Reasoning


  Causal models defined in terms of a collection of equations, as defined by
Pearl, are axiomatized here. Axiomatizations are provided for three
successively more general classes of causal models: (1) the class of recursive
theories (those without feedback), (2) the class of theories where the
solutions to the equations are unique, (3) arbitrary theories (where the
equations may not have solutions and, if they do, they are not necessarily
unique). It is shown that to reason about causality in the most general third
class, we must extend the language used by Galles and Pearl. In addition, the
complexity of the decision procedures is characterized for all the languages
and classes of models considered.

</DOC>
<DOC>
<DOCNO> 39868 </DOCNO>
Do Neutrinos Decay?


  If neutrinos have masses and mixings, in general some will decay. In models
with new particles and new couplings, some decay modes can be fast enough to be
of phenomenological interest.

</DOC>
<DOC>
<DOCNO> 100528 </DOCNO>
Unirationality of cubic hypersurfaces


  Segre proved that a smooth cubic surface over Q is unirational iff it has a
rational point. We prove that the result also holds for cubic hypersurfaces
over any field, including finite fields.

</DOC>
<DOC>
<DOCNO> 72035 </DOCNO>
An Alternative Method to Obtain the Quark Polarization of the Nucleon


  An alternate method is described to extract the quark contribution to the
spin of the nucleon directly from the first moment of the deuteron structure
function, $g^d_1$. It is obtained without recourse to the use of input on the
nucleon wave function from hyperon decays involving the flavor symmetry
parameters, F and D. The result for the quark polarization of the nucleon,
$\Delta\Sigma_ N,$ is in good agreement with the values of the singlet axial
current matrix element, $a_0$, obtained from recent next-to-leading order
analyses of current proton, neutron and deuteron data.

</DOC>
<DOC>
<DOCNO> 72088 </DOCNO>
Single scalar top production with polarized beams in ep collisions at


  From the point of view of the R-parity breaking supersymmetric model, we
propose a scalar top (stop) search with longitudinally polarized electron (e-)
and positron(e+) beams which will soon be available at the upgraded HERA. Fully
polarized e- or e+ beams could produce the stop two times as much as
unpolarized beams, while they increase background events due to the process of
the standard model by about 30% in comparison with unpolarized ones. We show
that right-handed e+ beams at HERA is efficient to produce the stop in the
model. With 1 fb**(-1) of integrated luminosity we estimate reach in the
coupling constant lambda'(131) for masses of the stop in the range 160-400 GeV.
We can set a 95% confidence-level exclusion limit for lambda'(131) > 0.01-0.05
in the stop mass range of 240-280 GeV if no singal of the stop is observed. We
also point out that y(=Q**2/sx) distributions of e+ coming from the stop shows
the different behavior from those of the standard model.

</DOC>
<DOC>
<DOCNO> 10257 </DOCNO>
Griffiths-McCoy singularities in random quantum spin chains: Exact


  The Ma-Dasgupta-Hu renormalization group (RG) scheme is used to study
singular quantities in the Griffiths phase of random quantum spin chains. For
the random transverse-field Ising spin chain we have extended Fisher's
analytical solution to the off-critical region and calculated the dynamical
exponent exactly. Concerning other random chains we argue by scaling
considerations that the RG method generally becomes asymptotically exact for
large times, both at the critical point and in the whole Griffiths phase. This
statement is checked via numerical calculations on the random Heisenberg and
quantum Potts models by the density matrix renormalization group method.

</DOC>
<DOC>
<DOCNO> 122113 </DOCNO>
The shape of pulsar radio beams


  Using all available multi-component radio pulse profiles for pulsars with
medium to long periods and good polarisation data, we have constructed a
two-dimensional image of the mean radio beamshape. This shows a peak near the
centre of the beam but is otherwise relatively uniform with only mild
enhancements in a few regions. This result supports the patchy-beam model for
emission beams in which the mean beam shape represents the properties of the
emission mechanism and observed pulse components result from emission sources
distributed randomly across the beam.

</DOC>
<DOC>
<DOCNO> 40011 </DOCNO>
Prospects for observations of high-energy cosmic tau neutrinos


  We study prospects for the observations of high-energy cosmic tau neutrinos
(E \geq 10^6 GeV) originating from proton acceleration in the cores of active
galactic nuclei. We consider the possibility that vacuum flavor neutrino
oscillations induce a tau to muon neutrino flux ratio greatly exceeding the
rather small value expected from intrinsic production. The criterias and event
rates for under water/ice light Cerenkov neutrino telescopes are given by
considering the possible detection of downgoing high-energy cosmic tau
neutrinos through characteristic double shower events.

</DOC>
<DOC>
<DOCNO> 102377 </DOCNO>
World volume Supermembrane Instantons in the light-cone frame


  In this review we present the octonionic duality for membranes. We start with
a discussion on the relation of the Yang Mills theories and the supermembrane
Hamiltonian in the light-cone gauge. We further derive the self-duality
equations for the membranes and discuss the integrability of the system in 7
and 3 dimensions. Finally, we present classical Euclidean time solutions of
these equations and examine the supersymmetries left intact by the self-duality
equations.

</DOC>
<DOC>
<DOCNO> 11707 </DOCNO>
Flow equation analysis of the anisotropic Kondo model


  We use the new method of infinitesimal unitary transformations to calculate
zero temperature correlation functions in the strong-coupling phase of the
anisotropic Kondo model. We find the dynamics on all energy scales including
the crossover behaviour from weak to strong coupling. The integrable structure
of the Hamiltonian is not used in our approach. Our method should also be
useful in other strong-coupling models since few other analytical methods allow
the evaluation of their correlation functions on all energy scales.

</DOC>
<DOC>
<DOCNO> 84531 </DOCNO>
Stochastic background of gravitational waves


  A continuous stochastic background of gravitational waves (GWs) for burst
sources is produced if the mean time interval between the occurrence of bursts
is smaller than the average time duration of a single burst at the emission,
i.e., the so called duty cycle must be greater than one. To evaluate the
background of GWs produced by an ensemble of sources, during their formation,
for example, one needs to know the average energy flux emitted during the
formation of a single object and the formation rate of such objects as well. In
many cases the energy flux emitted during an event of production of GWs is not
known in detail, only characteristic values for the dimensionless amplitude and
frequencies are known. Here we present a shortcut to calculate stochastic
backgrounds of GWs produced from cosmological sources. For this approach it is
not necessary to know in detail the energy flux emitted at each frequency.
Knowing the characteristic values for the ``lumped'' dimensionless amplitude
and frequency we show that it is possible to calculate the stochastic
background of GWs produced by an ensemble of sources.

</DOC>
<DOC>
<DOCNO> 118186 </DOCNO>
Thermal Instability and the Formation of Clumpy Gas Clouds


  The radiative cooling of optically thin gaseous regions and the formation of
a two-phase medium and of cold gas clouds with a clumpy substructure is
investigated. In optically thin clouds, the growth rate of small isobaric
density perturbations is independent of their length scale. However, the growth
of a perturbation is limited by its transition from isobaric to isochoric
cooling. The temperature at which this transition occurs decreases with the
length scale of the perturbation. Consequently small scale perturbations have
the potential to reach higher amplitudes than large scale perturbations. When
the amplitude becomes nonlinear, advection overtakes the pressure gradient in
promoting the compression resulting in an accelerated growth of the
disturbance. The critical temperature for transition depends on the initial
amplitude. The fluctuations which can first reach nonlinearity before their
isobaric to isochoric transition will determine the characteristic size and
mass of the cold dense clumps which would emerge from the cooling of an
initially nearly homogeneous region of gas. Thermal conduction is in general
very efficient in erasing isobaric, small-scale fluctuations, suppressing a
cooling instability. A weak, tangled magnetic field can however reduce the
conductive heat flux enough for low-amplitude fluctuations to grow isobarically
and become non-linear if their length scales are of order 0.01 pc. Finally, we
demonstrate how a 2-phase medium, with cold clumps being pressure confined in a
diffuse hot residual background component, would be sustained if there is
adequate heating to compensate the energy loss.

</DOC>
<DOC>
<DOCNO> 39961 </DOCNO>
Charge Asymmetry in 1-1000 GeV Electromagnetic Showers and Possibility


  For the high energy electromagnetic showers the thickness dependence of a)
the development of electron and positron components, b) the difference between
the secondary electron and positron numbers, c) the charge asymmetry of high
energy electromagnetic showers, as well as d) the spectral distributions of the
components at the shower maxima for various energies of primary particle
energies,1 - 1000 GeV were investigated employing GEANT Monte Carlo simulation
package. Using these simulation results it is discussed the possibility of
observation and study of the charge asymmetry with the help of a magnetic
spectrometer which is important for the current and future experiments on the
detection of radiowaves produced by high energy neutrinos.

</DOC>
<DOC>
<DOCNO> 100733 </DOCNO>
Identification of Berezin-Toeplitz deformation quantization


  We give a complete identification of the deformation quantization which was
obtained from the Berezin-Toeplitz quantization on an arbitrary compact Kaehler
manifold. The deformation quantization with the opposite star-product proves to
be a differential deformation quantization with separation of variables whose
classifying form is explicitly calculated. Its characteristic class (which
classifies star-products up to equivalence) is obtained. The proof is based on
the microlocal description of the Szegoe kernel of a strictly pseudoconvex
domain given by Boutet de Monvel and Sjoestrand.

</DOC>
<DOC>
<DOCNO> 70362 </DOCNO>
Non-Relativistic Effective Field Theory for Perturbative Heavy


  Recent developments for an effective theory for non-relativistic perturbative
quark-antiquark systems are reviewed and some applications are discussed.

</DOC>
<DOC>
<DOCNO> 40338 </DOCNO>
Fishing for Narrow Dibaryons in pd->pX Reaction


  An analysis of experimental data, obtained at the Linear Accelerator of INR,
is carried out with the aim of searching for supernarrow dibaryons in the
reactions pd->p+X and pd->p+pX_1. Dibaryons with masses 1904\pm 2, 1926\pm 2,
and 1942\pm 2 MeV have been observed in M_{X} missing mass spectra. In M_{X_1}
missing mass spectra, the peaks have been found at M_{X_1}=966\pm 2, 986\pm 2,
and 1003\pm 2 MeV. These values of M_{X_1} coincide with the ones obtained by a
simulation of a decay of the dibaryons into \gamma+pn. The analysis of the data
obtained leads to the conclusion that the observed dibaryons are supernarrow
dibaryons, the decay of which into two nucleons is forbidden by the Pauli
exclusion principle. A possible interpretation of exited nucleon states with
small masses is suggested.

</DOC>
<DOC>
<DOCNO> 118954 </DOCNO>
VLA 8.4-GHz monitoring observations of the CLASS gravitational lens


  The complex ten-component gravitational lens system B1933+503 has been
monitored with the VLA during the period February to June 1998 with a view to
measuring the time delay between the four compact components and hence to
determine the Hubble parameter. Here we present the results of an `A'
configuration 8.4-GHz monitoring campaign which consists of 37 epochs with an
average spacing of 2.8 days. The data have yielded light curves for the four
flat-spectrum radio components (components 1, 3, 4 and 6). We observe only
small flux density changes in the four flat-spectrum components which we do not
believe are predominantly intrinsic to the source. Therefore the variations do
not allow us to determine the independent time delays in this system. However,
the data do allow us to accurately determine the flux density ratios between
the four flat-spectrum components. These will prove important as modelling
constraints and could prove crucial in future monitoring observations should
these data show only a monotonic increase or decrease in the flux densities of
the flat-spectrum components.

</DOC>
<DOC>
<DOCNO> 116828 </DOCNO>
Laser Shaping and Optimization of the Laser-Plasma Interaction


  The physics of energy transfer between the laser and the plasma in laser
wakefield accelerators is studied. We find that wake excitation by arbitrary
laser shapes can be parameterized using the total pulse energy and pulse
depletion length. A technique for determining laser profiles that produce the
required plasma excitation is developed. We show that by properly shaping the
longitudinal profile of the driving laser pulse, it is possible to maximize
both the transformer ratio and the wake amplitude, achieving optimal
laser-plasma coupling. The corresponding family of laser pulse shapes is
derived in the nonlinear regime of laser-plasma interaction. Such shapes
provide theoretical upper limit on the magnitude of the wakefield and
efficiency of the accelerating stage by allowing for uniform photon
deceleration inside the laser pulse. We also construct realistic optimal pulse
shapes that can be produced in finite-bandwidth laser systems and propose a
two-pulse wake amplification scheme using the optimal solution.

</DOC>
<DOC>
<DOCNO> 68634 </DOCNO>
Electroweak Physics


  We review the prospects for studies in electroweak physics at the LHC.

</DOC>
<DOC>
<DOCNO> 84811 </DOCNO>
A theory of thin shells with orbiting constituents


  The self-gravitating, spherically symmetric thin shells built of orbiting
particles are sstudied. Two new features are found. One is the minimal possible
value for an angular momentum of particles, above which elleptic orbits become
possible. The second is the coexistence of both the wormhole solutions and the
elleptic or hyperbolic orbits for the same values of the parameters (but
different initial conditions). Possible applications of these results to
astrophysics and quantum black holes are briefly discussed.

</DOC>
<DOC>
<DOCNO> 120765 </DOCNO>
A 700 year-old Pulsar in the Supernova Remnant Kes 75


  Since their discovery 30 years ago, pulsars have been understood to be
neutron stars (NSs) born rotating rapidly (~ 10-100 ms). These neutron stars
are thought to be created in supernova explosions involving massive stars,
which give rise to expanding supernova remnants (SNRs). With over 220 Galactic
SNRs known (Green 1998) and over 1200 radio pulsars detected (Camilo et al.
2000), it is quite surprising that few associations between the two populations
have been identified with any certainty. Here we report the discovery of a
remarkable 0.3 sec X-ray pulsar, PSR J1846-0258, associated with the supernova
remnant Kes 75. With a characteristic age of only 723 yr, consistent with the
age of Kes 75, PSR J1846-0258 is the youngest pulsar yet discovered and is
being rapidly spun down by torques from a large magnetic dipole of strength ~
5E13 G, just above the so-called quantum critical field. PSR J1846-0258 resides
in this transitional regime where the magnetic field is hypothesized to
separate the regular pulsars from the so-called magnetars. PSR J1846-0258 is
evidently a Crab-like pulsar, however, its period, spin-down rate, spin-down
conversion efficiency, are each an order-of-magnitude greater, likely the
result of its extreme magnetic field.

</DOC>
<DOC>
<DOCNO> 100476 </DOCNO>
p-Adic Path Integrals for Quadratic Actions


  The Feynman path integral in p-adic quantum mechanics is considered. The
probability amplitude
    ${\cal K}_p (x^{\prime\prime},t^{\prime\prime}; x^\prime,t^\prime)$
 for one-dimensional systems with quadratic actions is calculated in an exact
form, which is the same as that in ordinary quantum mechanics.

</DOC>
<DOC>
<DOCNO> 151135 </DOCNO>
New vortex solution in SU(3) gauge-Higgs theory


  Following a brief review of known vortex solutions in SU(N) gauge-adjoint
Higgs theories we show the existence of a new ``minimal'' vortex solution in
SU(3) gauge theory with two adjoint Higgs bosons. At a critical coupling the
vortex decouples into two abelian vortices, satisfying Bogomol'nyi type, first
order, field equations. The exact value of the vortex energy (per unit length)
is found in terms of the topological charge that equals to the N=2
supersymmetric charge, at the critical coupling. The critical coupling signals
the increase of the underlying supersymmetry.

</DOC>
<DOC>
<DOCNO> 117555 </DOCNO>
Probing The Gravity Induced Bias with Weak Lensing: Test of Analytical


  Future weak lensing surveys will directly probe the density fluctuation in
the universe. Recent studies have shown how the statistics of the weak lensing
convergence field is related to the statistics of collapsed objects. Extending
earlier analytical results on the probability distribution function of the
convergence field we show that the bias associated with the convergence field
can directly be related to the bias associated with the statistics of
underlying over-dense objects. This will provide us a direct method to study
the gravity induced bias in galaxy clustering. Based on our analytical results
which use the hierarchical {\em ansatz} for non-linear clustering, we study how
such a bias depends on the smoothing angle and the source red-shift. We compare
our analytical results against ray tracing experiments through N-body
simulations of four different realistic cosmological scenarios and found a very
good match. Our study shows that the bias in the convergence map strongly
depends on the background geometry and hence can help us in distinguishing
different cosmological models in addition to improving our understanding of the
gravity induced bias in galaxy clustering.

</DOC>
<DOC>
<DOCNO> 71631 </DOCNO>
Neutrino mass matrix in Anti-GUT with see-saw mechanism


  We have investigated the predictions of neutrino oscillations within extended
Anti-GUT, based on a large gauge group - the Standard Model and an B-L abelian
group assumed with separate gauge fields coupling to each family of quarks and
leptons. We take into account corrections concerning a crude way of accounting
for the number of ways the vacuum expectation values of the Higgs fields of the
model can be ordered in the Feynman diagrams yielding the mass matrix elements.
Performing these corrections in a balanced way between the charged fermion
sector and the neutrino sector (case I) leads to the previous version of our
model that was a fit to the MSW small angle solution region. The fit considered
here is marginally worse that the previous fit inasmuch as it predicts a
somewhat lower solar neutrino mass square difference (which might though be the
only way of avoiding the day-night exclusion region). The other two versions
(case II and case III) are characterised by the heaviest of the see-saw
neutrino matrix elements that are composed either of \nu_{R\mu} and \nu_{R\tau}
or two \nu_{R\tau}. These cases II and III fit the small mixing angle MSW
scenario very well.

</DOC>
<DOC>
<DOCNO> 100326 </DOCNO>
Knot Invariants and New Quantum Field Theory


  We propose a new gauge theory of quantum electrodynamics (QED) and quantum
chromodynamics (QCD) from which we derive knot invariants such as the Jones
polynomial. Our approach is inspired by the work of Witten who derived knot
invariants from quantum field theory based on the Chern-Simon Lagrangian. From
our approach we can derive new knot invariants which extend the Jones
polynomial and give a complete classification of knots.

</DOC>
<DOC>
<DOCNO> 83328 </DOCNO>
Min-Max Fine Heaps


  In this paper we present a new data structure for double ended priority
queue, called min-max fine heap, which combines the techniques used in fine
heap and traditional min-max heap. The standard operations on this proposed
structure are also presented, and their analysis indicates that the new
structure outperforms the traditional one.

</DOC>
<DOC>
<DOCNO> 151017 </DOCNO>
Cosmology in the Randall-Sundrum Brane World Scenario


  The cosmology of the Randall-Sundrum scenario for a positive tension brane in
a 5-D Universe with localized gravity has been studied extensively recently.
Here we extend it to more general situations. We consider the time-dependent
situation where the two sides of the brane are different AdS/Schwarzschild
spaces. We show that the expansion rate in these models during inflation could
be larger than in brane worlds with compactified extra dimensions of fixed
size. The enhanced expansion rate could lead to the production of density
perturbations of substantially larger amplitude.

</DOC>
<DOC>
<DOCNO> 8844 </DOCNO>
Thermal/Electronic Transport Properties and Two-Phase Mixtures in


  We measured thermal conductivity, k, thermoelectric power, S, and dc electric
conductivity, sigma, of La_{5/8-x}Pr_{x}Ca_{3/8}MnO_{3}, showing an intricate
interplay between metallic ferromagnetism (FM) and charge ordering (CO)
instability. The change of k, S and sigma with temperature (T) and x agrees
well with the effective medium theories for binary metal-insulator mixtures.
This agreement clearly demonstrates that with the variation of T as well as x,
the relative volumes of FM and CO phases drastically change and percolative
metal-insulator transition occurs in the mixture of FM and CO domains.

</DOC>
<DOC>
<DOCNO> 102557 </DOCNO>
Non-intersecting Paths, Random Tilings and Random Matrices


  We investigate certain measures induced by families of non-intersecting paths
in domino tilings of the Aztec diamond, rhombus tilings of an abc-hexagon, a
dimer model on a cylindrical brick lattice and a growth model. The measures
obtained, e.g. the Krawtchouk and Hahn ensembles, have the same structure as
the eigenvalue measures in random matrix theory like GUE, which can in fact be
obtained from non-intersecting Brownian motions. The derivations of the
measures are based on the Karlin-McGregor or Lindstr\"om-Gessel-Viennot method.
We use the measure to show some asymptotic results for the models.

</DOC>
<DOC>
<DOCNO> 121765 </DOCNO>
Normal-Branch Quasi-Periodic Oscillations during the High Intensity


  Using data obtained with the Rossi X-ray Timing Explorer, we report the
detection of a 5 Hz quasi-periodic oscillation (QPO) in the bright low-mass
X-ray binary and Z source Cygnus X-2 during high overall intensities (the high
intensity state). This QPO was detected on the so-called normal branch and can
be identified with the normal branch QPO or NBO. Our detection of the NBO is
the first one during times when Cygnus X-2 was in the high intensity state. The
rms amplitude of this QPO decreased from 2.8% between 2-3.1 keV to <1.9%
between 5.0-6.5 keV. Above 6.5 keV, its amplitude rapidly increased to ~12% rms
above 16 keV. The time lags of the QPO were consistent with being zero below 5
keV (compared to the 2-3.1 keV band), but they rapidly increased to ~70 ms
around 10 keV, above which the time lags remained approximately constant near
70 ms. The photon energy dependencies of the rms amplitude and the time lags
are very similar to those observed for the NBO with other satellites (Ginga,
EXOSAT) at different (i.e. lower) intensity states.

</DOC>
<DOC>
<DOCNO> 118935 </DOCNO>
Hot Horizontal Branch Stars in the Galactic Bulge. I


  We present the first results of a survey of blue horizontal branch (BHB)
stars in the Galactic bulge. 164 candidates with 15 < V < 17.5 in a field
7.5deg from the Galactic Center were observed in the blue at 2.4A FWHM
resolution with the AAT 2dF spectrograph. Radial velocities were measured for
all stars. For stars with strong Balmer lines, their profiles were matched to
theoretical spectrum calculations to determine stellar temperature Teff and
gravity log g; matches to metal lines yielded abundances. CTIO UBV photometry
then gave the reddening and distance to each hot star. Reddening was found to
be highly variable, with E(B-V) from 0.0 to 0.55 around a mean of 0.28.
Forty-seven BHB candidates were identified with Teff >= 7250K, of which seven
have the gravities of young stars, three are ambiguous, and 37 are HB stars.
They span a wide metallicity range, from solar to 1/300 solar. The warmer BHB's
are more metal-poor and loosely concentrated towards the Galactic center, while
the cooler ones are of somewhat higher metallicity and closer to the center.
Their red B-V colors overlap main-sequence stars, but the U-B vs. B-V diagram
separates them until E(B-V) > 0.5. We detect two cool solar-metallicity HB
stars in the bulge of our own Galaxy, the first such stars known. Still elusive
are their hot counterparts, the metal-rich sdB/O stars causing excess UV light
in metal-rich galaxies; they have V ~ 20.5 in the Bulge.

</DOC>
<DOC>
<DOCNO> 116394 </DOCNO>
Crystalizing the genetic code


  New developments are presented in the framework of the model introduced by
the authors in refs. [1,2] and in which nucleotides as well as codons are
classified in crystal bases of the quantum group U_q(sl(2)+sl(2)) in the limit
q -> 0. An operator which gives the correspondence between the amino-acids and
the codons is now obtained for any known genetic code. The free energy released
by base pairing of dinucleotides as well as the relative hydrophilicity and
hydrophobicity of the dinucleosides are also computed. For the vertebrate
series, a universal behaviour in the ratios of codon usage frequencies is put
in evidence and is shown to fit nicely in our model. Then a first attempt to
represent the mutations relative to the deletion of a pyrimidine by action of a
suitable crystal spinor operator is proposed. Finally recent theoretical
descriptions are reviewed and compared with our model.

</DOC>
<DOC>
<DOCNO> 80930 </DOCNO>
Simulation of n_f =3 QCD by Hybrid Monte Carlo


  Simulations of odd flavors QCD can be performed in the framework of the
hybrid Monte Carlo algorithm where the inverse of the fermion matrix is
approximated by a polynomial. In this exploratory study we perform three
flavors QCD simulations. We make a comparison of the hybrid Monte Carlo
algorithm and the R-algorithm which also simulates odd flavors systems but has
step-size errors. We find that results from our hybrid Monte Carlo algorithm
are in agreement with those from the R-algorithm obtained at very small
step-size.

</DOC>
<DOC>
<DOCNO> 152539 </DOCNO>
Harmonic-Superspace Method Of Solving N=3 Super-Yang-Mills Equations


  We analyze the superfield constraints of the D=4, N=3 SYM-theory using
light-cone gauge conditions. The SU(3)/U(1) x U(1) harmonic variables are
interpreted as auxiliary spectral parameters, and the transform to the
harmonic-superspace representation is considered. The harmonic superfield
equations of motion are drastically simplified in our gauge, in particular, the
basic matrix of the harmonic transform and the corresponding harmonic analytic
gauge connections become nilpotent on-shell. It is shown that these harmonic
SYM-equations are equivalent to the finite set of solvable linear iterative
equations.

</DOC>
<DOC>
<DOCNO> 174525 </DOCNO>
(Anti)Proton and Pion Source Sizes and Phase Space Densities in Heavy


  NA44 has measured mid-rapidity deuteron spectra from AA collisions at
sqrt{s}=18GeV/A at the CERN SPS. Combining these spectra with published proton,
antiproton and antideuteron data allows us to calculate, within a coalescence
framework, proton and antiproton source sizes and phase space densities. These
results are compared to pion source sizes and densities, pA results and to
lower energy (AGS) data. The antiproton source is larger than the proton source
at sqrt{s}=18GeV/A. The phase space densities of pions and protons are not
constant but grow with system size. Both pi+ and proton radii decrease with
transverse mass and increase with sqrt{s}. Pions and protons do not freeze-out
independently. The nature of their interaction changes as sqrt{s}, and the
pion/proton ratio increases.

</DOC>
<DOC>
<DOCNO> 11581 </DOCNO>
Local absorption spectra of artificial atoms and molecules


  We investigate theoretically the spatial dependence of the linear absorption
spectra of single and coupled semiconductor quantum dots, where the strong
three-dimensional quantum confinement leads to an overall enhancement of
Coulomb interaction and, in turn, to a pronounced renormalization of the
excitonic properties. We show that -because of such Coulomb correlations and
the spatial interference of the exciton wavefunctions- unexpected spectral
features appear whose intensity depends on spatial resolution in a highly
non-monotonic way when the spatial resolution is comparable with the excitonic
Bohr radius. We finally discuss how the optical near-field properties of double
quantum dots are affected by their coupling.

</DOC>
<DOC>
<DOCNO> 70025 </DOCNO>
Electroweak double logarithms in inclusive observables for a generic


  High energy observables are characterized by large electroweak radiative
corrections of infrared origin; double logarithms are present even for
inclusive cross sections, thus violating the Bloch Nordsieck theorem. This
effect, related to the initial states carrying nonabelian isospin charges, is
here investigated for {\sl any} inclusive cross section in the
SU(2)$\otimes$U(1) symmetric limit, that is appropriate for energies much
higher than the weak scale. We develop a general formalism allowing to
calculate the all order double log resummed cross sections once the hard (tree
level) ones are known. The relevant cases of fermion-fermion, fermion-boson and
boson-boson scattering are discussed.

</DOC>
<DOC>
<DOCNO> 123296 </DOCNO>
An X-ray and Near-IR spectroscopic analysis of the ULIRG IRAS 05189-2524


  We present new, quasi-simultaneous hard X-ray and near-IR spectra of the
ultraluminous infrared galaxy IRAS 05189-2524, and discuss them together with
archival and literature data. The 1.9 Seyfert nucleus is Compton-thin. The
near-IR broad lines are seen in transmission, similarly to the X rays, and the
medium along the line of sight has an Av/Nh ratio definitely lower than
Galactic. The increase in obscuration observed at the latter epoch has (Delta
Av)/(Delta Nh) also less than Galactic, supporting a correlation between the
properties of the obscuring matter and its proximity to the center. The
measured Av is compatible with the broad component of Halpha being seen in
transmission, as opposed to scattering, so that most of the observed
polarization must be due to dichroism. The bolometric luminosity of the AGN,
deduced from the X-ray and line luminosities, falls definitely short of
accounting for the IR luminosity of the galaxy, consistent with its coolish
infrared color.

</DOC>
<DOC>
<DOCNO> 68301 </DOCNO>
Bilinear R-parity violating SUSY: Neutrinoless double beta decay in the


  Neutrinoless double beta ($\znbb$) decay is considered within bilinear
R-parity breaking supersymmetry, including the full one-loop corrections to the
neutrino-neutralino mass matrix. Expected rates for $\znbb$ decay in this model
are discussed in light of recent atmospheric and solar neutrino data. We
conclude that (a) tree-level calculations for $\znbb$ decay within the bilinear
model are not reliable in the range of parameters preferred by current solar
and atmospheric neutrino problems. And (b) if the solar and atmospheric
neutrino problems are to be solved within bilinear R-parity violating SUSY the
expected rates for $\znbb$ decay are very low; the effective Majorana neutrino
mass at most 0.01 eV and typical values being one order of magnitude lower.
Observing $\znbb$ decay in the next round of experiments therefore would rule
out the bilinear R-parity violating supersymmetric model as an explanation for
solar and atmospheric neutrino oscillations, as well as any hierarchical scheme
for neutrino masses, unless new neutrino interactions are present.

</DOC>
<DOC>
<DOCNO> 71181 </DOCNO>
The scalar field-theoretical Coulomb problem


  We analyze the fully relativistic, field-theoretical treatment of the scalar
Coulomb problem. We work in a truncated Hilbert-Fock space containing the
two-constituent states and the
two-constituent-and-one-massless-exchange-particle states. Self-energy
contributions are dominant for large values of the coupling constant. Using the
covariant formulation of the self-energy does not alter these results
significantly. Both the weak-coupling limit and the heavy-mass limit lead to
the non-relativistic results.

</DOC>
<DOC>
<DOCNO> 102438 </DOCNO>
Legendrian Submanifold Path Geometry


  Let $Z \to Y^{2n+1}$ be the bundle of Legendrian $n$-planes over a contact
manifold $Y$. We consider a foliation of $Z$ by canonical lifts of Legendrian
submanifolds, called \emph{Legendrian submanifold path geometry}, whose flat
model is \[ Sp(n+1, R) \to RP^{2n+1}. \] The equivalence problem provides an
$sp(n+1, R)$ valued Cartan connection form that captures the geometry of such
foliations.
  Two special cases are considered. The first case is characterized by having a
well defined conformal class of symmetric $(n+1)$ differentials on the space of
leaves of the foliation $X$. The $G$ structure induced on $X$ gives an example
of a classical non-metric, irreducible holonomy $GL(n+1,R)$ with representation
on $sym^2(R^{n+1})$.
  In the second example, we consider a \emph{Legendrian} connection on the
contact hyperplane vector bundle over $Y$ whose \emph{geodesic} Legendrian
submanifolds give rise to a desired foliation on $Z$. There exists a unique
\emph{normal symplectic} connection associated to a Legendrian connection
analogous to the normal projective connection for a torsion free affine
connection.
  For a nonflat example with symmetry, consider a hypersurface $M^n$ in the
$(n+1)$ dimensional space form $\bar{M}_c^{n+1}$, $c=1, 0,$ or -1, without any
extrinsic symmetry. The images of $M$ under the motion by
Iso($\bar{M}_c^{n+1}$), when lifted, generates a Legendrian submanifold path
geometry on $Gr(n, \bar{M}_c^{n+1})$.

</DOC>
<DOC>
<DOCNO> 121244 </DOCNO>
A Complete Survey of Case A Binary Evolution with Comparison to Observed


  We undertake a comparison of observed Algol-type binaries with a library of
computed Case A binary evolution tracks. The library consists of 5500 binary
tracks with various values of initial primary mass M_{10}, mass ratio q_0, and
period P_0, designed to sample the phase-space of Case A binaries in the range
-0.10 < log M_{10} < 1.7. Each binary is evolved using a standard code with the
assumption that both total mass and orbital angular momentum are conserved.
This code follows the evolution of both stars until the point where contact or
reverse mass transfer occurs. The resulting binary tracks show a rich variety
of behavior which we sort into several subclasses of Case A and Case B. We
present the results of this classification, the final mass ratio and the
fraction of time spent in Roche Lobe overflow for each binary system. The
conservative assumption under which we created this library is expected to hold
for a broad range of binaries, where both components have spectra in the range
G0 to B1 and luminosity class III - V. We gather a list of relatively
well-determined observed hot Algol-type binaries meeting this criterion, as
well as a list of cooler Algol-type binaries where we expect significant
dynamo-driven mass loss and angular momentum loss. We fit each observed binary
to our library of tracks using a chi^2-minimizing procedure. We find that the
hot Algols display overall acceptable chi^2, confirming the conservative
assumption, while the cool Algols show much less acceptable chi^2 suggesting
the need for more free parameters, such as mass and angular momentum loss.

</DOC>
<DOC>
<DOCNO> 100853 </DOCNO>
From the Bethe Ansatz to the Gessel-Viennot Theorem


  We state and prove several theorems that demonstrate how the coordinate Bethe
Ansatz for the eigenvectors of suitable transfer matrices of a generalised
inhomogeneous five-vertex model on the square lattice, given certain conditions
hold, is equivalent to the Gessel-Viennot determinant for the number of
configurations of $N$ non-intersecting directed lattice paths, or vicious
walkers, with various boundary conditions. Our theorems are sufficiently
general to allow generalisation to any regular planar lattice.

</DOC>
<DOC>
<DOCNO> 7987 </DOCNO>
Andreev scattering and Josephson current in a one-dimensional electron


  Andreev scattering and the Josephson current through a one-dimensional
interacting electron liquid sandwiched between two superconductors are
re-examined. We first present some apparently new results on the
non-interacting case by studying an exactly solvable tight-binding model rather
than the usual continuum model. We show that perfect Andreev scattering (i.e.
zero normal scattering) at the Fermi energy can only be achieved by fine-tuning
junction parameters. We also obtain exact results for the Josephson current,
which is generally a smooth function of the superconducting phase difference
except when the junction parameters are adjusted to give perfect Andreev
scattering, in which case it becomes a sawtooth function. We then observe that,
even when interactions are included, all low energy properties of a junction
(E<<\Delta, the superconducting gap) can be obtained by "integrating out" the
superconducting electrons to obtain an effective Hamiltonian describing the
metallic electrons only with a boundary pairing interaction. This boundary
model provides a suitable starting point for bosonization/renormalization
group/boundary conformal field theory analysis. We argue that total normal
reflection and total Andreev reflection correspond to two fixed points of the
boundary renormalization group. For repulsive bulk interactions the Andreev
fixed point is unstable and the normal one stable. However, the reverse is true
for attractive interactions. This implies that a generic junction Hamiltonian
(without fine-tuned junction parameters) will renormalize to the normal fixed
point for repulsive interactions but to the Andreev one for attractive
interactions. An exact mapping of our tight-binding model to the Hubbard model
with a transverse magnetic field is used to help understand this behavior.

</DOC>
<DOC>
<DOCNO> 121403 </DOCNO>
The Coma cluster luminosity function from ultraviolet to near-infrared


  [Abridged] The Coma cluster luminosity function (LF) from ultraviolet (2000
AA) to the near-infrared (H band) is summarized. In the UV the LF is very
steep, much steeper than in the optical. The steep Coma UV LF implies that
faint and bright galaxies give similar contributions to the total UV flux and
to the total metal production rate. The Coma UV LF is dominated by star forming
galaxies, not by massive and large galaxies. The optical Coma LF is relatively
steep (alpha=-1.4) over the 11 magnitudes sampled. We found a clear steeping of
the FL going from B to R bands, indicative of the presence of a large number of
red dwarfs, as faint as three bright globular clusters. Furthermore, using
Hubble Space Telescope images, we discover that blends of globular clusters,
not resolved in individual components due to seeing, look like dwarf galaxies
when observed from the ground and are numerous and bright. The existence of
these fake extended sources increases the steepness of the LF at faint
magnitudes, if not deal on. The near-infrared LF was computed on a
near-infrared selected sample of galaxies which photometry is complete down to
the typical dwarf (M^*+5) luminosity. The Coma LF can be described by a
Schechter function with intermediate slope (alpha~-1.3), plus a dip at M_H~-22
mag. The shape of the Coma LF in H band is quite similar to the one found in
the B band. The similarity of the LF in the optical and H bands implies that in
the central region of Coma there is no new population of galaxies which is too
faint to be observed in the optical band (because dust enshrouded, for
instance), down to the magnitudes of dwarfs.

</DOC>
<DOC>
<DOCNO> 170807 </DOCNO>
Wigner Functions with Boundaries


  We consider a general Wigner function for a particle confined to a finite
interval and subject to Dirichlet boundary conditions. We derive the boundary
corrections to the "star-genvalue" equation and to the time evolution equation.
These corrections can be cast in the form of a boundary potential contributing
to the total Hamiltonian. Moreover, in this context, it is the boundary
potential that is responsible for the discretization of the energy levels as is
illustrated by the example of the free particle in the infinite potential well.
Finally, using the Weyl map we show that the boundary potentials can be
obtained directly from standard operator quantum mechanics.

</DOC>
<DOC>
<DOCNO> 80686 </DOCNO>
Domain Wall Fermions with Exact Chiral Symmetry


  We show how the standard domain wall action can be simply modified to allow
arbitrarily exact chiral symmetry at finite fifth dimensional extent. We note
that the method can be used for both quenched and dynamical calculations. We
test the method using smooth and thermalized gauge field configurations. We
also make comparisons of the performance (cost) of the domain wall operator for
spectroscopy compared to other methods such as the overlap-Dirac operator and
find both methods are comparable in cost.

</DOC>
<DOC>
<DOCNO> 69928 </DOCNO>
SUSY-QCD corrections to the MSSM $h^0 b \bar b$ vertex in the decoupling


  We analyze the supersymmetric (SUSY) QCD contribution to the $h^0 b \bar{b}$
coupling at one loop in the Minimal Supersymmetric Model (MSSM) in the
decoupling limit. Analytic expressions in the large SUSY mass region are
derived and the decoupling behavior of the corrections is examined in various
limiting cases, where some or all of the SUSY mass parameters become large. We
show that in the decoupling limit of large SUSY mass parameters and large
CP-odd Higgs mass, the $h^0 b \bar b$ coupling approaches its Standard Model
value at one loop. However, the onset of decoupling is delayed when $\tan\beta$
is large. In addition, the one-loop SUSY-QCD corrections decouple if the masses
of either the bottom squarks or the gluino are separately taken large; although
the approach to decoupling is significantly slower in the latter case.

</DOC>
<DOC>
<DOCNO> 99782 </DOCNO>
Normal CR structures on compact 3-manifolds


  We study normal CR compact manifolds in dimension 3. For a choice of a CR
Reeb vector field, we associate a Sasakian metric on them, and we classify
those metrics. As a consequence, the underlying manifolds are topologically
finite quotiens of the 3-sphere or of a circle bundle over a Riemann surface of
positive genus. In the latter case, we prove that their CR automorphisms group
is a finite extension of U(1), and we classify the normal CR structures on
these manifolds.

</DOC>
<DOC>
<DOCNO> 69739 </DOCNO>
Enhanced electric dipole moment of the muon in the presence of large


  The electric dipole moment of the muon (d_mu) is evaluated in supersymmetric
models with nonzero neutrino masses and large neutrino mixing arising from the
seesaw mechanism. It is found that if the seesaw mechanism is embedded in the
framework of a left-right symmetric gauge structure, the interactions
responsible for the right-handed neutrino Majorana masses lead to an
enhancement in d_mu. We find d_mu as large as 5. 10^{-23} ecm with a correlated
value of (g-2) = 13. 10^{-10}, even for low values of tan beta. This should
provide a strong motivation for improving the edm of the muon to the level of
10^{-24} ecm as has recently been proposed.

</DOC>
<DOC>
<DOCNO> 40503 </DOCNO>
The Future of Diffraction at Tevatron


  This paper summarizes the main current upgrade for Diffractive Physics at
Tevatron. We describe both CDF and D0 new devices that are being installed
around the CDF and D0 area that will allow to produce new results in
Diffractive Physics.

</DOC>
<DOC>
<DOCNO> 122813 </DOCNO>
On the Fine Structure in the Fireballs Peak of the 1998 Leonids


  The Leonids meteor shower of November 1998 has shown a double activity. An
unexpected shower of fireballs occurred about 16 hours before the expected
maximum of the meteor activity. The activity profile of the fireball shower
revealed also a fine structure. The hypotesis of tidal origin of such
sub-structures is discussed. The close encounter of the meteoroid stream with
the Earth in 1366 and the encounters with Saturn (in 1630) and Jupiter (in
1732), are identified as the cause of the main features of the structure. Such
analysis can be applied to the incoming 2000 Leonids' display.

</DOC>
<DOC>
<DOCNO> 178424 </DOCNO>
Triplet Pairing in Neutron Matter


  The separation method developed earlier by us [Nucl. Phys. {\bf A598} 390
(1996)] to calculate and analyze solutions of the BCS gap equation for
$^1$S$_0$ pairing is extended and applied to $^3$P$_2$--$^3$F$_2$ pairing in
pure neutron matter. The pairing matrix elements are written as a separable
part plus a remainder that vanishes when either momentum variable is on the
Fermi surface. This decomposition effects a separation of the problem of
determining the dependence of the gap components in a spin-angle representation
on the magnitude of the momentum (described by a set of functions independent
of magnetic quantum number) from the problem of determining the dependence of
the gap on angle or magnetic projection. The former problem is solved through a
set of nonsingular, quasilinear integral equations, providing inputs for
solution of the latter problem through a coupled system of algebraic equations
for a set of numerical coefficients. An incisive criterion is given for finding
the upper critical density for closure of the triplet gap. The separation
method and its development for triplet pairing exploit the existence of a small
parameter, given by a gap-amplitude measure divided by the Fermi energy. The
revised BCS equations admit analysis revealing universal properties of the full
set of solutions for $^3$P$_2$ pairing in the absence of tensor coupling,
referring especially to the energy degeneracy and energetic order of these
solutions. The angle-average approximation introduced by Baldo et al. is
illuminated in terms of the separation-transformed BCS problem and the small
parameter expansion...

</DOC>
<DOC>
<DOCNO> 9965 </DOCNO>
Deviations from linear theory for fluctuations below the supercritical


  We report measurements of thermally-induced mean-square director-angle
fluctuations <theta^2> below primary supercritical bifurcations to
electroconvection of the nematic liquid crystals I52 and "Merck Phase V". For
epsilon_mf = V^2/V_c,mf^2 - 1 < -0.1 (V is the amplitude of the applied
alternating voltage) we find <theta^2> proportional to epsilon_mf^(-gamma) with
gamma given by linear theory (LT). Closer to the bifurcation there are
deviations from LT with a smaller gamma and with V_c^2 > V_c,mf^2. For I52
measurements as a function of the conductivity sigma of <theta^2> above V_c^2
suggest a tricritical bifurcation at sigma_t = 4.0 x 10^(-9) Omega^(-1)m^(-1),
and (V_c^2 - V_c,mf^2)/V_c^2 increases strongly as sigma_t is approached from
above.

</DOC>
<DOC>
<DOCNO> 83237 </DOCNO>
Estimation of English and non-English Language Use on the WWW


  The World Wide Web has grown so big, in such an anarchic fashion, that it is
difficult to describe. One of the evident intrinsic characteristics of the
World Wide Web is its multilinguality. Here, we present a technique for
estimating the size of a language-specific corpus given the frequency of
commonly occurring words in the corpus. We apply this technique to estimating
the number of words available through Web browsers for given languages.
Comparing data from 1996 to data from 1999 and 2000, we calculate the growth of
a number of European languages on the Web. As expected, non-English languages
are growing at a faster pace than English, though the position of English is
still dominant.

</DOC>
<DOC>
<DOCNO> 123210 </DOCNO>
FUSE Observations of an X-Ray Bright Region in the Vela Supernova


  We present the results of a FUSE observation of an X-ray selected knot in the
Vela supernova remnant. Spectra were obtained through the 30"x30" low
resolution aperture and the 4"x20" medium resolution aperture. O VI 1032,1038
and C III 977 are detected strongly in both spectra, and S VI 933,944 is
detected weakly only in the larger aperture spectrum. We also report the first
detection of C II 1037 emission in a supernova remnant. The spectra show the
presence of two kinematic components along the line of sight - one with both
low and high excitation emission centered at a velocity of -50 km/s and another
with only low excitation emission centered at a velocity of +100 km/s. We
associate the -50 km/s component with the observed X-ray knot, and find a
dynamical pressure of 3.7x10^{-10} dyne cm^{-2} driving the shock. We compare
our results with data obtained using the Hopkins Ultraviolet Telescope at
nearby locations and find that differences in the spectra imply the existence
of two emitting components in the X-ray knot. Based on the X-ray morphology
seen in a ROSAT HRI image, we identify two distinct regions which can be
associated with these two components whose ultraviolet emission differs
dramatically. These observations demonstrate the importance of high spectral
resolution in understanding the proper physical relationships between the
various emitting components in supernova remnants.

</DOC>
<DOC>
<DOCNO> 120612 </DOCNO>
Comparison of photometric parameters of LSB and HSB edge-on galaxies


  Photometric parameters of stellar disks and bulges for several edge-on
galaxies from the Catalog of Flat Galaxies (FGC) were determined. We discuss a
difference between photometric parameters of LSB and HSB galaxies from our
sample.
  Also we present results of R CCD photometry of edge-on galaxy RFGC 3647.
Deprojecting this galaxy we show that it has thin LSB disk (central surface
brightness $22^m.2$ in R) and high ratio of radial to vertical scale lengths.
It is shown that initially gaseous disk of the galaxy was unstable and its
velocity dispersion was low. Stellar disk of this LSB galaxy was not heated
significantly since that time.

</DOC>
<DOC>
<DOCNO> 12647 </DOCNO>
Friction in a solid lubricant film


  Molecular dynamics study of a thin (one to five layers) lubricant film
between two substrates in moving contact are performed using Langevin equations
with an external damping coefficient depending on distance and velocity of
atoms relative the substrates, motivated by microscopic configurations. They
show that the minimal friction coefficient is obtained for the solid-sliding
regime. A detailed analysis of the results, the comparison with other
microscopic modeling approaches of friction, and the evaluation of quantities
that can be compared to experiments, such as the velocity of the transition
from stick-slip to smooth sliding, are used to discuss the relevance of the
microscopic simulations of friction.

</DOC>
<DOC>
<DOCNO> 85206 </DOCNO>
Fermions without Vierbeins in Curved Space-Time


  A general formulation of spinor fields in Riemannian space-time is given
without using vierbeins. The space-time dependence of the Dirac matrices
required by the anticommutation relation
{\gamma_{\mu},\gamma_{\nu}}=2g_{\mu\nu} determines the spin connection. The
action is invariant under any local spin base transformations in the 32
parameter group Gl(4,c) and not just under local Lorentz transformations. The
Dirac equation and the energy-momentum tensor are computed from the action.

</DOC>
<DOC>
<DOCNO> 118269 </DOCNO>
Resonant inverse Compton scattering by secondary pulsar plasma


  We consider resonant inverse Compton scattering of thermal photons by
secondary particles above the pulsar polar gap. The process appears to be an
essential energy loss mechanism for the particles. The distribution function of
the secondary plasma particles is found to be strongly affected by the
scattering. It becomes two-humped implying the development of two-stream
instability. The resonantly upscattered Compton photons are found to gain
energy of 1 - 10 MeV forming an additional component in the pulsar gamma-ray
spectrum. The corresponding gamma-ray flux is estimated as well.

</DOC>
<DOC>
<DOCNO> 122267 </DOCNO>
Ultra - High Energy Cosmic Rays from decay of the Super Heavy Dark


  In this paper we briefly discuss the problem of the origin of Ultra High
Energy Cosmic Rays in the framework of Top-Down models. We show that, for high
energy of decays and in a wide range of spectra of injected protons, their
extragalactic flux is consistent with the observed fluxes of cosmic rays in the
energy range 0.1 E_{GZK}< E < 10E_{GZK}. For suitable energy and spectra of
injected protons, the contribution of galactic sources is moderate, in this
energy range, but it dominates at smaller and larger energies. In such models
we can expect that at these energies the anisotropy of cosmic rays distribution
over sky will be especially small.
  Some possible manifestations of decays of super massive particles such as,
for example, primordial black holes with masses M_{pbh} ~ 10^{-5} g, are
considered. In particular, we show that partial conversion of energy released
during these decays at redshifts z ~ 1000 to Ly-alpha photons can delay the
hydrogen recombination and distort the spectrum of fluctuations of the cosmic
microwave background radiation.

</DOC>
<DOC>
<DOCNO> 178906 </DOCNO>
Dynamical Study of the Delta Excitation in N(e,e' pi) Reactions


  The dynamical model developed in [Phys. Rev. C 54, 2660 (1996)] has been
applied to investigate the pion electroproduction reactions on the nucleon. It
is found that the model can describe to a very large extent the recent data of
p(e,e' pi^0) reaction from Jefferson Laboratory and MIT-Bates. The extracted
magnetic dipole(M1), electric dipole(E2), and Coulomb(C2) strengths of the
gamma N -> Delta transition are presented. It is found that the C2/M1 ratio
drops significantly with Q^2 and reaches about -13% at Q^2=4 (GeV/c)^2, while
the E2/M1 ratio remains close to the value \sim -3 % at the Q^2=0 photon point.
The determined M1 transition form factor drops faster than the usual dipole
form factor of the proton. We also find that the non-resonant interactions can
dress the gamma N -> Delta vertex to enhance strongly its strength at low Q^2,
but much less at high Q^2. Predictions are presented for future experimental
tests. Possible developments of the model are discussed.

</DOC>
<DOC>
<DOCNO> 68459 </DOCNO>
Analytic Continuation of Mellin Transforms up to two-loop Order


  The analytic continuation of the Mellin transforms to complex values of N for
the basic functions $g_i(x)$ of the momentum fraction x emerging in the
quantities of massless QED and QCD up to two-loop order, as the unpolarized and
polarized splitting functions, coefficient functions, and hard scattering cross
sections for space- and time-like momentum transfer are evaluated. These Mellin
transforms provide the analytic continuations of all finite harmonic sums up to
the level of the threefold sums of transcendentality four, where the basis-set
${g_i(x)}$ consists of products of {\sc Nielsen}-integrals up to
transcendentality four. The computer code {\tt ANCONT} is provided.

</DOC>
<DOC>
<DOCNO> 9899 </DOCNO>
Quantum Cellular Neural Networks


  We have previously proposed a way of using coupled quantum dots to construct
digital computing elements - quantum-dot cellular automata (QCA). Here we
consider a different approach to using coupled quantum-dot cells in an
architecture which, rather that reproducing Boolean logic, uses a physical
near-neighbor connectivity to construct an analog Cellular Neural Network
(CNN).

</DOC>
<DOC>
<DOCNO> 117674 </DOCNO>
Mirror Dark Matter and Core Density of Galaxies


  We present a particle physics realization of a recent suggestion by Spergel
and Steinhardt that collisional but dissipationless dark matter may resolve the
core density problem in dark matter-dominated galaxies such as the dwarf
galaxies. The realization is the asymmetric mirror universe model introduced to
explain the neutrino puzzles and the microlensing anomaly. The mirror baryons
are the dark matter particles with the desired properties. The time scales are
right for resolution of the core density problem and formation of mirror stars
(MACHOs observed in microlensing experiments). The mass of the region
homogenized by Silk damping is between a dwarf and a large galaxy.

</DOC>
<DOC>
<DOCNO> 85183 </DOCNO>
Computing the Complete Gravitational Wavetrain from Relativistic Binary


  We present a new method for generating the nonlinear gravitational wavetrain
from the late inspiral (pre-coalescence) phase of a binary neutron star system
by means of a numerical evolution calculation in full general relativity. In a
prototype calculation, we produce 214 wave cycles from corotating polytropes,
representing the final part of the inspiral phase prior to reaching the ISCO.
Our method is based on the inequality that the orbital decay timescale due to
gravitational radiation is much longer than an orbital period and the
approximation that gravitational radiation has little effect on the structure
of the stars. We employ quasi-equilibrium sequences of binaries in circular
orbit for the matter source in our field evolution code. We compute the
gravity-wave energy flux, and, from this, the inspiral rate, at a discrete set
of binary separations. From these data, we construct the gravitational waveform
as a continuous wavetrain. Finally, we discuss the limitations of our current
calculation, planned improvements, and potential applications of our method to
other inspiral scenarios.

</DOC>
<DOC>
<DOCNO> 85551 </DOCNO>
The Einstein 3-form G_a and its equivalent 1-form L_a in Riemann-Cartan


  The definition of the Einstein 3-form G_a is motivated by means of the
contracted 2nd Bianchi identity. This definition involves at first the complete
curvature 2-form. The 1-form L_a is defined via G_a = L^b \wedge #(o_b \wedge
o_a). Here # denotes the Hodge-star, o_a the coframe, and \wedge the exterior
product. The L_a is equivalent to the Einstein 3-form and represents a certain
contraction of the curvature 2-form. A variational formula of Salgado on
quadratic invariants of the L_a 1-form is discussed, generalized, and put into
proper perspective.

</DOC>
<DOC>
<DOCNO> 101329 </DOCNO>
Images of eigenvalue distributions under power maps


  In [earlier work by the author], it was shown that if U is a random n x n
unitary matrix, then for any p>=n, the eigenvalues of U^p are i.i.d. uniform;
similar results were also shown for general compact Lie groups. We study what
happens when p<n instead. For the classical groups, we find that we can
describe the eigenvalue distribution of U^p in terms of the eigenvalue
distributions of smaller classical groups; the earlier result is then a special
case. The proofs rely on the fact that a certain subgroup of the Weyl group is
itself a Weyl group. We generalize this fact, and use it to study the power-map
problem for general compact Lie groups.

</DOC>
<DOC>
<DOCNO> 117294 </DOCNO>
Electromagnetic Induction and the Conservation of Momentum in the Spiral


  The inversion of cause and effect in the classic description of
electromagnetism, gives rise to a conceptual error which is at the bottom of
many paradoxes and exceptions. At present, the curious fact that unipolar
induction or the Faraday Disc constitutes an exception to the Faraday induction
law is generally accepted. When we establish the correct cause and effect
relationship a close connection appears between mechanics and electromagnetism,
as does a new induction law for which paradoxes or exceptions do not occur.
Some paradoxical experiments in unipolar induction involving the unique
geometry of the spiral are described demonstrating the inversion of cause and
effect. The emf and torque of the Faraday Disc and the conducting spiral is due
to the continuous variation of the electromagnetic angular moment of the
continuous current. This experiments confirm the Lorentz Force and invalidate
Faradays Induction Law. They show how in a closed circuit emf and unipolar
torque are not produced by the variation in magnetic flux, which is constant,
but by two variations in the electromagnetic angular moment. The three possible
ways of varying the electromagnetic angular moment generated by the circulation
of the charges gives rise to the different forms of electromagnetic induction.

</DOC>
<DOC>
<DOCNO> 122143 </DOCNO>
On the apparent coupling of neutral hydrogen and dark matter in spiral


  We have studied a mass model for spiral galaxies in which the dark matter
surface density is a scaled version of the observed HI surface density.
Applying this mass model to a sample of 24 spiral galaxies with reliable
rotation curves one obtains good fits for most galaxies. The scaling factors
cluster around 7, after correction for the presence of primordial helium. But
for several cases different, often larger, values are found. For galaxies that
can not be fitted well the discrepancy occurs at large radii and results from a
fairly rapid decline of the HI surface density in the outermost regions.
Because of such imperfections and in view of possible selection effects it is
not possible to conclude here that there is a real coupling between HI and dark
matter in spiral galaxies.

</DOC>
<DOC>
<DOCNO> 69861 </DOCNO>
Light Sgoldstino: Precision Measurements versus Collider Searches


  We study sensitivity of low-energy experiments to the scale of supersymmetry
breaking $\sqrt{F}$ in models with light sgoldstinos --- superpartners of
goldstino. The limits on $\sqrt{F}$ may be obtained from direct and indirect
measurements of sgoldstino coupling to photons, leptons, mesons and nucleons.
There are three sources of constraints: ($i$) astrophysics and cosmology;
($ii$) precision laboratory experiments at low energies; ($iii$) rare decays.
We discuss only processes with real sgoldstinos. For sgoldstino lighter than a
few MeV and superpartner masses of the order of electroweak scale,
astrophysical and reactor bounds on $\sqrt{F}$ are significantly stronger than
limits which may be reached at future colliders. In models with heavier
sgoldstino (up to 5 GeV), constraints from flavor conserving decays of mesons
are complementary to ones coming from collider experiments. The most sensitive
probes of sgoldstinos are flavor violating processes, provided that flavor is
violated in squark and/or slepton sector. It is shown that sgoldstino
contributions into FCNC and lepton flavor violation are strong enough to probe
the supersymmetry breaking scale up to $\sqrt{F}\sim10^7$ GeV, if off-diagonal
entries in squark (slepton) mass matrices are close to the current limits in
MSSM.

</DOC>
<DOC>
<DOCNO> 119490 </DOCNO>
The BeppoSAX view of NLS1s


  The main results of broad-band (0.1-10 keV) BeppoSAX observations of a
selected sample of NLS1s are presented and discussed. It is shown that all the
available data are consistent with a scenario in which NLS1s are running at a
high accretion rate.

</DOC>
<DOC>
<DOCNO> 69213 </DOCNO>
Photoproduction of top in peripheral heavy ion collisions


  In relativistic heavy ion collisions, top quarks can be produced by
photon-gluon fusion when a photon from the Weizs\"acker-Williams virtual photon
field of one nucleus interacts with a gluon in the other nucleus.
Photoproduction with heavy ions at the Large Hadron Collider (LHC) will be the
first accessible non-hadronic top production channel. We calculate the $t \bar
t$ photoproduction cross sections, pair mass and top quark rapidity
distributions in peripheral heavy ion collisions. The cross sections are
sensitive to the top quark charge and the large-$Q^2$ gluon distribution in the
nucleus. We find a cross section of 94 pb in calcium-calcium collisions,
leading to 190 pairs in a one month ($10^6$ sec) LHC run. We also find $p$Pb
and $p$Ca cross sections of 5.8 and 3.4 pb respectively, resulting in 6 and 34
$t\bar t$ pairs per month.

</DOC>
<DOC>
<DOCNO> 69029 </DOCNO>
Possible Signature of Low Scale Gravity in Ultra High Enegry Cosmic Rays


  We show that the existence of low scale gravity at TeV scale could lead to a
direct production of photons with energies above 10^22 eV due to annihilation
of ultra high energy neutrinos on relic massive neutrinos of the galactic halo.
Air showers initialized in the terrestrial atmosphere by these ultra energetic
photons could be collected in near future by the new generation of cosmic ray
experiments.

</DOC>
<DOC>
<DOCNO> 10301 </DOCNO>
A non trivial extension of the two-dimensional Ising model: the


  A recently proposed molecular model is discussed as a non-trivial extension
of the Ising model. For d=2 the two models are shown to be equivalent, while
for d>2 the molecular model describes a peculiar second order transition from
an isotropic high temperature phase to a low-dimensional anisotropic low
temperature state. The general mean field analysis is compared with the results
achieved by a variational Migdal-Kadanoff real space renormalization group
method and by standard Monte Carlo sampling for d=3. By finite size scaling the
critical exponent has been found to be 0.44\pm 0.02 thus establishing that the
molecular model does not belong to the universality class of the Ising model
for d>2.

</DOC>
<DOC>
<DOCNO> 84174 </DOCNO>
The electrogravity transformation and global monopoles in scalar-tensor


  The electrogravity transformation is defined by an interchange of the
``active'' and ``passive'' electric parts of the Riemann tensor. Such a
transformation has been used to find new solutions that are ``dual'' to the
Kerr family of black hole spacetimes in general relativity. In such a case, the
dual solution is a similar black hole spacetime endowed with a global monopole
charge. Here, we extend this formalism to obtain solutions dual to the static,
spherically symmetric solutions of two different scalar-tensor gravity
theories. In particular, we first study the duals of the charged black hole
solutions of a four-dimensional low-energy effective action of heterotic string
theory. Next, we study dual of the Xanthopoulos-Zannias solution in Brans-Dicke
theory, which contains a naked singularity. We show that, analogous to general
relativity, in these scalar-tensor gravity theories the dual solutions are
similar to the original spacetimes, but with a global monopole charge.

</DOC>
<DOC>
<DOCNO> 84122 </DOCNO>
Reconstruction of a scalar-tensor theory of gravity in an accelerating


  The present acceleration of the Universe strongly indicated by recent
observational data can be modeled in the scope of a scalar-tensor theory of
gravity. We show that it is possible to determine the structure of this theory
(the scalar field potential and the functional form of the scalar-gravity
coupling) along with the present density of dustlike matter from the following
two observable cosmological functions: the luminosity distance and the linear
density perturbation in the dustlike matter component as functions of redshift.
Explicit results are presented in the first order in the small inverse
Brans-Dicke parameter 1/omega.

</DOC>
<DOC>
<DOCNO> 102005 </DOCNO>
Positive knots and knots with braid index three have property_p


  We prove that positive knots and knots with braid index three in the 3-sphere
satisfy the Property P conjecture.

</DOC>
<DOC>
<DOCNO> 8044 </DOCNO>
The critical earthquake concept applied to mine rockbursts with


  We report new tests of the critical earthquake concepts performed on
rockbursts in deep South African mines. We extend the concept of an optimal
time and space correlation region and test it on the eight main shocks of our
catalog provided by ISSI. In a first test, we use the simplest signature of
criticality in terms of a power law time-to-failure formula. Notwithstanding
the fact that the search for the optimal correlation size is performed with
this simple power law, we find evidence both for accelerated seismicity and for
the presence of logperiodic behavior with a prefered scaling factor close to 2.
We then propose a new algorithm based on a space and time smoothing procedure,
which is also intended to account for the finite range and time mechanical
interactions between events. This new algorithm provides a much more robust and
efficient construction of the optimal correlation region, which allows us the
use of the logperiodic formula directly in the search process. In this
preliminary work, we have only tested the new algorithm on the largest event on
the catalog. The result is of remarkable good quality with a dramatic
improvement in accuracy and robustness. This confirms the potential importance
of logperiodic signals. Our study opens the road for an efficient implemention
of a systematic testing procedure of real-time predictions.

</DOC>
<DOC>
<DOCNO> 121818 </DOCNO>
A High Resolution Study of the Hydra A Cluster with Chandra: Comparison


  The cooling flow cluster Hydra A was observed during the orbital activation
and calibration phase of the Chandra Observatory. While the X-ray image of the
cluster exhibits complex structure in the central region as reported in
McNamara $etal$, the large scale X-ray morphology of the cluster is fairly
smooth. A spectroscopic analysis of the ACIS data shows that the gas
temperature in Hydra A increases outward, reaches a maximum temperature of 4
keV at 200 kpc, and then decreases slightly at larger radii. The distribution
of heavy elements is nonuniform, with a factor of two increase in the Fe and Si
abundances within the central 100 kpc. Beyond the central 100 kpc the Si-to-Fe
abundance ratio is twice solar, while the Si-to-Fe ratio of the central excess
is consistent with the solar value. One of the more surprising results is the
lack of spectroscopic evidence for multiphase gas within the bulk of the
cooling flow. Beyond the central 30 kpc, the ACIS spectra are adequately fit
with a single temperature model. The addition of a cooling flow component does
not significantly improve the fit. Only within the central 30 kpc (where the
cooling time is less than 1~Gyr), is there spectroscopic evidence for
multiphase gas. However, the spectroscopic mass deposition rate is more than a
factor of 10 less than the morphologically derived mass accretion rate at 30
kpc. We propose that the cooling flow region is convectively unstable due to
heating by the central radio source which significantly reduces the net
accretion rate.

</DOC>
<DOC>
<DOCNO> 116855 </DOCNO>
Production And Studies Of Photocathodes For High Intensity Electron


  For short, high-intensity electron bunches, alkali-tellurides have proved to
be a reliable photo-cathode material. Measurements of lifetimes in an RF gun of
the CLIC Test Facility II at field strengths greater than 100 MV/m are
presented. Before and after using them in this gun, the spectral response of
the Cs-Te and Rb-Te cathodes were determined with the help of an optical
parametric oscillator. The behaviour of both materials can be described by
Spicer's 3-step model. Whereas during the use the threshold for photo-emission
in Cs-Te was shifted to higher photon energies, that of Rb-Te did not change.
Our latest investigations on the stoichiometric ratio of the components are
shown. The preparation of the photo-cathodes was monitored with 320 nm
wavelength light, with the aim of improving the measurement sensitivity. The
latest results on the protection of Cs-Te cathode surfaces with CsBr against
pollution are summarized. New investigations on high mean current production
are presented.

</DOC>
<DOC>
<DOCNO> 101599 </DOCNO>
Small Eigenvalues of Large Hankel Matrices


  In this paper we investigate the smallest eigenvalue, denoted as $\la_N,$ of
a $(N+1)\times (N+1)$ Hankel or moments matrix, associated with the weight,
$w(x)=\exp(-x^{\bt}),x>0,\bt>0$, in the large $N$ limit. Using a previous
result, the asymptotics for the polynomials, $P_n(z),z\notin[0,\infty)$,
orthonormal with respect to $w,$ which are required in the determination of
$\la_N$ are found. Adopting an argument of Szeg\"{o} the asymptotic behaviour
of $\la_N$, for $\bt>1/2$ where the related moment problem is determinate, is
derived. This generalises the result given by Szeg\"{o} for $\bt=1$. It is
shown that for $\bt>1/2$ the smallest eigenvalue of the infinite Hankel matrix
is zero, while for $0<\bt<1/2$ it is greater then a positive constant. This
shows a phase transition in the corresponding Hermitian random matrix model as
the parameter $\bt$ varies with $\bt=1/2$ identified as the critical point. The
smallest eigenvalue at this point is conjectured.

</DOC>
<DOC>
<DOCNO> 10446 </DOCNO>
True Superconductivity in a 2D "Superconducting-Insulating" System


  We present results on disordered amorphous films which are expected to
undergo a field-tuned Superconductor-Insulator Transition. Based on low-field
data and I-V characteristics, we find evidence of a low temperature
Metal-to-Superconductor transition. This transition is characterized by
hysteretic magnetoresistance and discontinuities in the I-V curves. The
metallic phase just above the transition is different from the "Fermi Metal"
before superconductivity sets in.

</DOC>
<DOC>
<DOCNO> 71408 </DOCNO>
Weak matrix elements and K-meson physics


  An overview is presented about old and recent methods to compute the $K\to
\pi \pi$ decay amplitude.

</DOC>
<DOC>
<DOCNO> 174468 </DOCNO>
Semi-Inclusive Lambda and Kshort Production in p-Au Collisions at 17.5


  The first detailed measurements of the centrality dependence of strangeness
production in p-A collisions are presented. Lambda and Kshort dn/dy
distributions from 17.5 GeV/c p-Au collisions are shown as a function of "grey"
track multiplicity and the estimated number of collisions, nu, made by the
proton. The nu dependence of the Lambda yield deviates from a scaling of p-p
data by the number of participants, increasing faster than this scaling for
nu<=5 and saturating for larger nu. A slower growth in Kshort multiplicity with
nu is observed, consistent with a weaker nu dependence of K-Kbar production
than Y-K production.

</DOC>
<DOC>
<DOCNO> 71749 </DOCNO>
QED Effective Actions in Inhomogeneous Backgrounds: Summing the


  The QED effective action encodes nonlinear interactions due to quantum vacuum
polarization effects. While much is known for the special case of electrons in
a constant electromagnetic field (the Euler-Heisenberg case), much less is
known for inhomogeneous backgrounds. Such backgrounds are more relevant to
experimental situations. One way to treat inhomogeneous backgrounds is the
"derivative expansion", in which one formally expands around the soluble
constant-field case. In this talk I use some recent exactly soluble
inhomogeneous backgrounds to perform precision tests on the derivative
expansion, to learn in what sense it converges or diverges. A closely related
question is to find the exponential correction to Schwinger's pair-production
formula for a constant electric field, when the electric background is
inhomogeneous.

</DOC>
<DOC>
<DOCNO> 152460 </DOCNO>
Branes from Unstable Systems of Branes


  We discuss various aspects of the description of branes as topological
solitons in unstable brane systems of higher dimensions. We first describe a
classification of all the possible realisations of branes of M and type II
theories as topological solitons of a brane-antibrane system. We then present a
description of type IIB NS-NS p-branes in terms of topological solitons in
systems of spacetime-filling NS9, anti-NS9 pairs and discuss the implications
of these constructions in the description of BPS and non-BPS states in the
strongly coupled Heterotic SO(32) theory. We finally present briefly the
construction of a conjectured spacetime-filling non-BPS M10-brane, starting
point for a brane descent construction of the branes of M-theory.

</DOC>
<DOC>
<DOCNO> 10490 </DOCNO>
Continuum description of avalanches in granular media


  We develop a continuum description of partially fluidized granular flows. Our
theory is based on the hydrodynamic equation for the flow coupled with the
order parameter equation which describes the transition between flowing and
static components of the granular system. This theory captures important
phenomenology recently observed in experiments with granular flows on rough
inclined planes (Daerr and Douady, Nature (London) v. 399, 241 (1999)): layer
bistability, and transition from triangular avalanches propagating downhill at
small inclination angles to balloon-shaped avalanches also propagating uphill
for larger angles.

</DOC>
<DOC>
<DOCNO> 118666 </DOCNO>
Realizing 3D Spectral Imaging in the Far-Infrared: FIFI LS


  We present a progress report on the design and construction of the
Field-Imaging Far-Infrared Line Spectrometer (FIFI LS) for the SOFIA airborne
observatory. The design of the instrument is driven by the goal of maximizing
observing efficiency, especially for observations of faint, extragalactic
objects. Thus, FIFI LS utilizes an integral field technique that uses slicer
mirrors to optically re-arrange the two-dimensional field into a single slit
for a long slit spectrometer. Effectively, a 5x5 pixel spatial field of view is
imaged to a 25x1 pixel slit and dispersed to a 25x16 pixel, two-dimensional
detector array, providing diffraction-limited spatial and spectral
multiplexing. In this manner, the instrument employs two parallel, medium
resolution (R~2000) grating spectrometers for simultaneous observations in two
bands: a short wavelength band (42 to 110 micron) and a long wavelength band
(110 to 210 micron). Overall, for each of the 25 spatial pixels, the instrument
can cover a velocity range of ~1500 km/s around selected far-infrared lines
with an estimated sensitivity of 2x10^-15 W Hz^1/2 per pixel. This arrangement
provides good spectral coverage with high responsivity.
  ***This paper does not include Figures due to astro-ph size limitations.
Please download entire file at http://fifi-ls.mpe-garching.mpg.de/fifils.ps.gz
****

</DOC>
<DOC>
<DOCNO> 119136 </DOCNO>
The UV spectrum of nebulae


  This paper presents an analysis of the UV spectrum of some nebulae with
clearly identified illuminating stars, all observed by the IUE satellite.
  The data show remarkable properties of the UV spectrum of the nebulae. Each
spectrum is the product of the star spectrum and a linear function of 1/lambda.
There is no peculiar behaviour in the spectrums at 2200A: no bump created in
the spectrum of a nebula and no excess of scattering. When moving away from the
star, the surface brightness of a nebula decreases as the inverse of the square
of the angular distance to the star.
  These results can logically be interpreted in terms of scattering of
starlight. They imply constant properties of the interstellar grains in the UV
and in the directions of space sampled by the nebulae, and probably a strong
forward scattering phase function. There is no evidence for any particular type
of grain which would specifically extinguish starlight at 2200A.
  Concerning the UV spectrum of a star, this may imply a revisal of the
traditional interpretation of the 2200A bump.

</DOC>
<DOC>
<DOCNO> 69469 </DOCNO>
Democratic Universal Seesaw Model with Three Light Sterile Neutrinos


  Based on the "democratic" universal seesaw model, where mass matrices $M_f$
of quarks and leptons f_i (f=u,d,\nu,e; i=1,2,3) are given by a seesaw form
M_f\simeq -m_L M_F^{-1} m_R, and m_L and m_R are universal for all the fermion
sectors, and the mass matrices M_F of hypothetical heavy fermions F_i have a
democratic structure, a possible neutrino mass matrix is investigated. In the
model, there are three sterile neutrinos \nu_{iR} which mix with the active
neutrinos \nu_{iL} with \theta \sim 10^{-2} and which are harmless for
constraint from the bib bang nucleosynthesis. The atmospheric, solar and LSND
neutrino data are explained by the mixings \nu_{\mu L} \leftrightarrow\nu_{\tau
L}, \nu_{eL}\leftrightarrow \nu_{eR} and \nu_{eL}\leftrightarrow \nu_{\mu L},
respectively. The model predicts that \Delta m^2_{solar}/\Delta m^2_{atm}
\simeq (R^2-1) m_e/\sqrt{m_\mu m_\tau} [R=m(\nu_{iR})/m(\nu_{iL}) (i=1,2,3)]
with \sin^{2}2\theta_{atm}\simeq 1 and \Delta m_{LSND}^2/\Delta m^2_{atm}
\simeq (1/4)\sqrt{m_\mu/m_e} with \sin^2 2\theta_{LSND} \simeq 4m_e/m_\mu.

</DOC>
<DOC>
<DOCNO> 84566 </DOCNO>
Generalized entropy and Noether charge


  We find an expression for the generalized gravitational entropy of Hawking in
terms of Noether charge. As an example, the entropy of the Taub-Bolt spacetime
is calculated.

</DOC>
<DOC>
<DOCNO> 84692 </DOCNO>
Canonical Gravity, Diffeomorphisms and Objective Histories


  This paper discusses the implementation of diffeomorphism invariance in
purely Hamiltonian formulations of General Relativity. We observe that, if a
constrained Hamiltonian formulation derives from a manifestly covariant
Lagrangian, the diffeomorphism invariance of the Lagrangian results in the
following properties of the constrained Hamiltonian theory: the diffeomorphisms
are generated by constraints on the phase space so that a) The algebra of the
generators reflects the algebra of the diffeomorphism group. b) The Poisson
brackets of the basic fields with the generators reflects the space-time
transformation properties of these basic fields. This suggests that in a purely
Hamiltonian approach the requirement of diffeomorphism invariance should be
interpreted to include b) and not just a) as one might naively suppose. Giving
up b) amounts to giving up objective histories, even at the classical level.
This observation has implications for Loop Quantum Gravity which are spelled
out in a companion paper. We also describe an analogy between canonical gravity
and Relativistic particle dynamics to illustrate our main point.

</DOC>
<DOC>
<DOCNO> 169594 </DOCNO>
Universal Quantum Entanglement Concentration Gate


  We construct a Universal Quantum Entanglement Concentration Gate (QEC-Gate).
Special times operations of QEC-Gate can transform a pure 2-level bipartite
entangled state to nearly maximum entanglement. The transformation can attain
any required fidelity with optimal probability by adjusting concentration step.
We also generate QEC-Gate to the Schmidt decomposable multi-partite system.

</DOC>
<DOC>
<DOCNO> 11197 </DOCNO>
Learning and generation of long-range correlated sequences


  We study the capability to learn and to generate long-range, power-law
correlated sequences by a fully connected asymmetric network. The focus is set
on the ability of neural networks to extract statistical features from a
sequence. We demonstrate that the average power-law behavior is learnable,
namely, the sequence generated by the trained network obeys the same
statistical behavior. The interplay between a correlated weight matrix and the
sequence generated by such a network is explored. A weight matrix with a
power-law correlation function along the vertical direction, gives rise to a
sequence with a similar statistical behavior.

</DOC>
<DOC>
<DOCNO> 122605 </DOCNO>
On the Origin of the Fanaroff-Riley Dichotomy


  A small fraction of double radio sources show a peculiar and striking hybrid
morphology; they have a distinctly FR I structure on one side of the nucleus,
and a FR II structure on the other. We argue that the mere existence of these
HYMORS is quite incompatible with the theoretical explanations for the
Fanaroff-Riley dichotomy that are based upon the nature of the jet plasma, or
those invoking an intrinsic property of the central engine. Rather, these
HYMORS strongly support models that explain the difference between FR I and FR
II sources in terms of asymmetry of interaction of the jets with the external
environments. We further show that a model for radio source dynamics we had
earlier proposed can neatly reproduce the observed dependence of the radio
power dividing the two FR classes on the optical luminosity of the host galaxy,
as found by Owen & White and Ledlow & Owen

</DOC>
<DOC>
<DOCNO> 119610 </DOCNO>
The chemical evolution of gas-rich dwarf galaxies


  A numerical double burst model of the chemical evolution of gas-rich dwarf
galaxies has been developed. The model is fitted to a sample of N/O, O/H, Y and
gas fraction observations, where N/O and O/H are the relative abundances by
number of nitrogen to oxygen and oxygen to hydrogen, respectively. Y is the
abundance by mass of helium. Closed models as well as models including enriched
outflow, ordinary outflow and ordinary outflow combined with inflow are
considered.The bursts are assumed to be instantaneous but ordered in pairs to
explain the scatter in N/O-O/H. The method of gas fraction fitting is revised,
and it is found that it is very important to specify whether dwarf irregulars
(dIrrs) or blue compact galaxies (BCGs) are considered. Effective enriched
winds fail when fitting N/O, whereas closed models, models with ordinary winds
or a combination of ordinary winds and inflow are all viable.

</DOC>
<DOC>
<DOCNO> 119190 </DOCNO>
Old White Dwarfs as a Microlensing Population


  A popular interpretation of recent microlensing studies of the line of sight
towards the Large Magellanic Cloud invokes a population of old white dwarf
stars in the Galactic halo. Below I review the basic properties of old white
dwarf stars and the ongoing efforts to detect this population directly.

</DOC>
<DOC>
<DOCNO> 71481 </DOCNO>
Production of Two Photons and a Jet Through Gluon Fusion


  We have computed the cross-section and distributions for the production of
two photons and a jet via the process $g g \to \gamma\gamma g$. In the Standard
Model, this process occurs at the one-loop level through pentagon and box
diagrams. We show that at the LHC this is a significant mechanism for the
production of the two photons and a jet. This process is also an important
background to the Higgs boson production, when the Higgs boson decays into two
photons. We also explorethis process at the Tevatron.

</DOC>
<DOC>
<DOCNO> 69794 </DOCNO>
Pulsar acceleration by asymmetric emission of sterile neutrinos


  A convincing explanation for the observed pulsar large peculiar velocities is
still missing. We argue that any viable particle physics solution would most
likely involve the resonant production of a non-interacting neutrino $\nu_s$ of
mass $m_{\nu_s}\sim 20$--50 keV. We propose a model where anisotropic magnetic
field configurations strongly bias the resonant spin flavour precession of tau
antineutrinos into $\nu_s$. For internal magnetic fields $B_{int} \gsim
10^{15}$ G a $\bar\nu_\tau$-$\nu_s$ transition magnetic moment of the order of
$10^{-12}$ Bohr magnetons is required. The asymmetric emission of $\nu_s$ from
the core can produce sizeable natal kicks and account for recoil velocities of
several hundred kilometers per second.

</DOC>
<DOC>
<DOCNO> 101903 </DOCNO>
Asymmetries in the Shanks-Renyi Prime Number Race


  It has been well-observed that an inequality of the type $\pi(x;q,a) >
\pi(x;q,b)$ is more likely to hold if $a$ is a non-square modulo $q$ and $b$ is
a square modulo $q$ (the so-called ``Chebyshev Bias''). For instance, each of
$\pi(x;8,3)$, $\pi(x;8,5)$, and $\pi(x;8,7)$ tends to be somewhat larger than
$\pi(x;8,1)$. However, it has come to light that the tendencies of these three
$\pi(x;8,a)$ to dominate $\pi(x;8,1)$ have different strengths. A related
phenomenon is that the six possible inequalities of the form $\pi(x;8,a_1) >
\pi(x;8,a_2) > \pi(x;8,a_3)$ with $\{a_1,a_2,a_3\}=\{3,5,7\}$ are not all
equally likely---some orderings are preferred over others. In this paper we
discuss these phenomena, focusing on the moduli $q=8$ and $q=12$, and we
explain why the observed asymmetries (as opposed to other possible asymmetries)
occur.

</DOC>
<DOC>
<DOCNO> 121288 </DOCNO>
Multiresolution Analysis of Substructure in Dark Matter Halos


  Multiresolution analysis is applied to the problem of halo identification in
cosmological N-body simulations. The procedure makes use of a discrete wavelet
transform known as the a trous algorithm in combination with segmentation
analysis. It has the ability to find halos in dense environments and to
separate multiple levels of substructure, as is illustrated in the analysis of
a 500,000 particle halo. Over 600 subhalos are identified and their physical
properties are discussed.

</DOC>
<DOC>
<DOCNO> 13879 </DOCNO>
Spectrum and thermodynamic currents in one dimensional Josephson


  The dc Josephson effect is considered from the thermodynamic point of view.
Universal thermodynamic equations, relating both bound and continuum
contributions to the Josephson current with the normal electron scattering
amplitudes are derived for the single mode case. To derive these equations we
use and further develop the method of spatial separation between the
superconducting and normal parts of the junction. We also use this method to
find the Andreev bound states in structures containing superconducting
components. The general thermodynamic formulas are applied to the calculation
of the current in various Josephson-type structures. In particular, the crucial
role of the continuum contribution is demonstrated, even for short junctions
(where it is usually neglected). We also find structures where the bound states
supporting the giant currents are well separated; thus they can, hopefully, be
populated nonuniformly and such current can be measured.

</DOC>
<DOC>
<DOCNO> 170146 </DOCNO>
Negative phase time for Scattering at Quantum Wells: A Microwave Analogy


  If a quantum mechanical particle is scattered by a potential well, the wave
function of the particle can propagate with negative phase time. Due to the
analogy of the Schr\"odinger and the Helmholtz equation this phenomenon is
expected to be observable for electromagnetic wave propagation. Experimental
data of electromagnetic wells realized by wave guides filled with different
dielectrics confirm this conjecture now.

</DOC>
<DOC>
<DOCNO> 117841 </DOCNO>
The Equation of State of Neutron-Star Matter in Strong Magnetic Fields


  We study the effects of very strong magnetic fields on the equation of state
(EOS) in multicomponent, interacting matter by developing a covariant
description for the inclusion of the anomalous magnetic moments of nucleons.
For the description of neutron star matter, we employ a field-theoretical
approach which permits the study of several models which differ in their
behavior at high density. Effects of Landau quantization in ultra-strong
magnetic fields ($B>10^{14}$ Gauss) lead to a reduction in the electron
chemical potential and a substantial increase in the proton fraction. We find
the generic result for $B>10^{18}$ Gauss that the softening of the EOS caused
by Landau quantization is overwhelmed by stiffening due to the incorporation of
the anomalous magnetic moments of the nucleons. In addition, the neutrons
become completely spin polarized. The inclusion of ultra-strong magnetic fields
leads to a dramatic increase in the proton fraction, with consequences for the
direct Urca process and neutron star cooling. The magnetization of the matter
never appears to become very large, as the value of $|H/B|$ never deviates from
unity by more than a few percent. Our findings have implications for the
structure of neutron stars in the presence of large frozen-in magnetic fields.

</DOC>
<DOC>
<DOCNO> 122128 </DOCNO>
The Dawn of Galaxies: Deep MAMBO Imaging Surveys


  We discuss results from sensitive, wide-field imaging of the millimeter
extragalactic background using the Max-Planck Millimeter Bolometer array
(MAMBO) at the IRAM 30m telescope.

</DOC>
<DOC>
<DOCNO> 170256 </DOCNO>
Local Distinguishability of Multipartite Orthogonal Quantum States


  We consider one copy of a quantum system prepared in one of two orthogonal
pure states, entangled or otherwise, and distributed between any number of
parties. We demonstrate that it is possible to identify which of these two
states the system is in by means of local operations and classical
communication alone. The protocol we outline is both completely reliable and
completely general - it will correctly distinguish any two orthogonal states
100% of the time.

</DOC>
<DOC>
<DOCNO> 10004 </DOCNO>
Electronic states in correlated three-coupled chains


  Three-coupled chains of quarter-filled Hubbard model with dimerization have
been studied for periodic boundary conditions. By use of a renormalization
group method, it is found that the interchain hopping is renormalized to zero
leading to confinement when charge gap becomes larger than the effective
interchain hopping energy. Such a result of confinement is compared with that
of two-coupled chains.

</DOC>
<DOC>
<DOCNO> 85047 </DOCNO>
Local existence proofs for the boundary value problem for static


  We prove local existence and uniqueness of static spherically symmetric
solutions of the Einstein-Yang-Mills equations for an arbitrary compact
semisimple gauge group in the so-called regular case. By this we mean the
equations obtained when the rotation group acts on the principal bundle on
which the Yang-Mills connection takes its values in a particularly simple way
(the only one ever considered in the literature). The boundary value problem
that results for possible asymptotically flat soliton or black hole solutions
is very singular and just establishing that local power series solutions exist
at the center and asymptotic solutions at infinity amounts to a nontrivial
algebraic problem. We discuss the possible field equations obtained for
different group actions and solve the algebraic problem on how the local
solutions depend on initial data at the center and at infinity.

</DOC>
<DOC>
<DOCNO> 150450 </DOCNO>
Anomaly Matching and a Hopf-Wess-Zumino Term in 6d, N=(2,0) Field


  We point out that the low energy theory of 6d, N=(2,0) field theories, when
away from the origin of the moduli space of vacua, necessarily includes a new
kind of Wess-Zumino term. The form of this term is related to the Hopf
invariant associated with \pi_7 (S^4). The coefficient of the Wess-Zumino term
is fixed by an anomaly matching relation for a global flavor symmetry. For
example, in the context of a single M5 brane probe in the background of N
distant M5 branes, the probe must have the Hopf-WZ term with coefficient
proportional to N(N+1). Various related checks and observations are made. We
also point out that there are skyrmionic strings, and propose that they are the
W-boson strings.

</DOC>
<DOC>
<DOCNO> 100755 </DOCNO>
Integrable highest weight modules over affine superalgebras and Appell's


  We classify integrable irreducible highest weight representations of
non-twisted affine Lie superalgebras. We give a free field construction in the
level~1 case. The analysis of this construction shows, in particular, that in
the simplest case of the $s\ell (2|1)$ level~1 affine superalgebra the
characters are expressed in terms of the Appell elliptic function. Our results
demonstrate that the representation theory of affine Lie superalgebras is quite
different from that of affine Lie algebras.

</DOC>
<DOC>
<DOCNO> 69854 </DOCNO>
The Strong Isospin-Breaking Correction for the Gluonic Penguin


  The strong isospin-breaking correction, Omega_{st}, which appears in
estimates of the Standard Model value for the direct CP-violating ratio
epsilon'/epsilon, is evaluated to next-to-leading order (NLO) in the chiral
expansion using Chiral Perturbation Theory. The relevant linear combinations of
the unknown NLO CP-odd weak low-energy constants (LEC's) which, in combination
with 1-loop and strong LEC contributions, are required for a complete
determination at this order, are estimated using two different models. It is
found that, to NLO, Omega_{st}=0.08 +/- 0.05, significantly reduced from the
``standard'' value, 0.25 +/- 0.08, employed in recent analyses. The potentially
significant numerical impact of this decrease on Standard Model predictions for
epsilon'/epsilon, associated with the decreased cancellation between gluonic
penguin and electroweak penguin contributions, is also discussed.

</DOC>
<DOC>
<DOCNO> 117165 </DOCNO>
Studies of Beam Optics and Scattering in the Next Linear Collider


  We present a new conceptual and optical design for the Next Linear Collider
post-linac collimation system. Energy collimation and passive protection
against off-energy beams are achieved in a system with large horizontal
dispersion and vertical betatron functions. Betatron collimation is performed
in a relatively low-beta (FODO-like) lattice in which only thin spoilers
intercept particles near the beam core, while thick absorbers maintain a large
stay-clear from the beam. Two possible schemes for the spoilers are considered:
one in which the spoilers are capable of tolerating a certain number of
damaging interceptions per collider run ("consumable" spoilers), and one in
which the spoilers are potentially damaged on every machine pulse and are
self-repairing ("renewable" spoilers). The collimation efficiency of the system
is evaluated, considering both halo particles which are rescattered into the
beam and muon secondaries which are passed to the interaction region. We
conclude that the new design is a promising candidate for the NLC post-linac
system.

</DOC>
<DOC>
<DOCNO> 101432 </DOCNO>
Bounds for Local Density of Sphere Packings and the Kepler Conjecture


  This paper describes the local density inequality approach to getting upper
bounds for sphere packing densities in R^n. This approach was first suggested
by L. Fejes-Toth in 1956 to prove the Kepler conjecture that the densest sphere
packing in R^3 is the "cannonball packing". The approaches of L. Fejes-Toth,
W.-Y. Hsiang, and T. Hales to the Kepler conjecture are each based on
(different) local density inequalities. Recently T. Hales and S. P. Ferguson
have presented extensive details carrying out a modified version of the
otrignal Hales approach to prove the Kepler conjecture. We describe the
particular local density inequality undelying the Hales and Ferguson approach
and sketch some features of their proof.

</DOC>
<DOC>
<DOCNO> 85575 </DOCNO>
Black-Hole Uncertainty Entails an Intrinsic Time Arrow. a Note on the


  Any theory that states that the basic laws of physics are time-symmetric must
be strictly deterministic. Only determinism enables time reversal of entropy
increase. A contradiction therefore arises between two statements of Hawking. A
simulation of a system under time reversal shows how an intrinsic time arrow
re-emerges, destroying the time reversal, when even slight failure of
determinism occurs.

</DOC>
<DOC>
<DOCNO> 122340 </DOCNO>
The Importance of Nonlinear H2 Photoexcitiation in Strongly Irradiated


  It is shown that, under sufficiently intense OB-star illumination of a
stationary photoexcitation front (PDR), nonlinear H2 photoexcitation processes
comprising driven resonant two-photon transitions between X-state quantum
levels, with VUV continuum light from the star supplying both driving fields,
largely determine the photonic pathways of H2 molecules in the PDR close to the
ionization front. Specifically, for a PDR irradiated by a 0.1-pc-distant B0 III
star, the total rate at which an H2 molecule is nonlinearly photoexcited out of
any X-state quantum level is calculated to be roughly 100 times greater than
the total rate at which it is linearly photoexcited out of the same level. In
strongly excited PDRs, the populations in almost all of the ~300 bound quantum
levels of the X state will be maintained approximately equal via a few myriads
of interconnecting two-photon steps. The remarkable importance of two-photon
transitions in H2 photoexcitation in strongly irradiated PDRs derives from the
exceptionally narrow Raman linewidth that characterizes all two-photon
transitions between bound H2 X-state quantum levels.

</DOC>
<DOC>
<DOCNO> 119976 </DOCNO>
Classical Cepheid pulsation models. VI. The Hertzsprung progression


  We present the results of an extensive theoretical investigation on the
pulsation behavior of Bump Cepheids. We constructed several sequences of full
amplitude, nonlinear, convective models by adopting a chemical composition
typical of Large Magellanic Cloud (LMC) Cepheids (Y=0.25, Z=0.008) and stellar
masses ranging from 6.55 to 7.45 solar masses. We find that theoretical light
and velocity curves reproduce the HP, and indeed close to the blue edge the
bump is located along the descending branch, toward longer periods it crosses
at first the luminosity/velocity maximum and then it appears along the rising
branch. In particular, we find that the predicted period at the HP center is
11.24 +- 0.46 d and that such a value is in very good agreement with the
empirical value estimated by adopting the Fourier parameters of LMC Cepheid
light curves. We also find that the models at the HP center are located within
the resonance region but not on the 2:1 resonance line. Interestingly enough,
the predicted Bump Cepheid masses, based on a Mass-Luminosity (ML) relation
which neglects the convective core overshooting, are in good agreement with the
empirical masses of Galactic Cepheids estimated by adopting the Baade-Wesselink
method. Even by accounting for the metallicity difference between Galactic and
LMC Cepheids, this result seems to settle down the long-standing problem of the
Bump mass discrepancy. Finally, the dynamical behavior of a cool Bump Cepheid
model provides a plain explanation of an ill-understood empirical evidence.

</DOC>
<DOC>
<DOCNO> 8324 </DOCNO>
CORE and the Haldane Conjecture


  The Contractor Renormalization group formalism (CORE) is a real-space
renormalization group method which is the Hamiltonian analogue of the Wilson
exact renormalization group equations. In an earlier paper\cite{QGAF} I showed
that the Contractor Renormalization group (CORE) method could be used to map a
theory of free quarks, and quarks interacting with gluons, into a generalized
frustrated Heisenberg antiferromagnet (HAF) and proposed using CORE methods to
study these theories. Since generalizations of HAF's exhibit all sorts of
subtle behavior which, from a continuum point of view, are related to
topological properties of the theory, it is important to know that CORE can be
used to extract this physics. In this paper I show that despite the folklore
which asserts that all real-space renormalization group schemes are necessarily
inaccurate, simple Contractor Renormalization group (CORE) computations can
give highly accurate results even if one only keeps a small number of states
per block and a few terms in the cluster expansion. In addition I argue that
even very simple CORE computations give a much better qualitative understanding
of the physics than naive renormalization group methods. In particular I show
that the simplest CORE computation yields a first principles understanding of
how the famous Haldane conjecture works for the case of the spin-1/2 and spin-1
HAF.

</DOC>
<DOC>
<DOCNO> 70682 </DOCNO>
Rho Electroproduction and the Hadronic Contribution to Deeply Virtual


  A two-gluon-exchange model incorporating perturbative and non-perturbative
effects is presented for rho electroproduction which provides an excellent
description of all current data. This is then used to calculate the
contribution from the rho to deeply virtual Compton scattering via the
vector-meson-dominance transition rho -> gamma. This is found to be
sufficiently large to provide a significant contribution through interference
with the perturbative QCD term.

</DOC>
<DOC>
<DOCNO> 122172 </DOCNO>
Vacuum gaps in pulsars and PSR J2144-3933


  In this paper we revisit the radio pulsar death line problem within the
framework of curvature radiation and/or inverse compton scattering induced
vacuum gap model above neutron star polar caps. Our special interest is in the
recently detected pulsar PSR J2144-3933 with extremal period 8.5 seconds, which
lies far beyond conventional death lines. We argue, that formation of vacuum
gaps requires a complicated multipolar surface magnetic field, with a strenght
$B_s$ much higher than the surface dipolar component $B_d$, and radii of
curvature ${\cal R}$ much smaller than the neutron star radius $R=10^6$ cm.
Such a multipolar surface field is also consistent with death lines including
the extremal pulsar PSR J2144-3933. Since vacuum gap models produce sparks, our
paper naturally supports the spark related models of subpulse drift phenomenon
as well as to the spark associated models of coherent pulsar radio emission.

</DOC>
<DOC>
<DOCNO> 68384 </DOCNO>
The QCD heavy-quark potential to order v^2: one loop matching conditions


  The one-loop QCD heavy quark potential is computed to order v^2 in the color
singlet and octet channels. Several errors in the previous literature are
corrected. To be consistent with the velocity power counting, the full
dependence on |p' + p|/|p' - p| is kept. The matching conditions for the NRQCD
one-loop potential are computed by comparing the QCD calculation with that in
the effective theory. The graphs in the effective theory are also compared to
terms from the hard, soft, potential, and ultrasoft regimes in the threshold
expansion. The issue of off-shell versus on-shell matching and gauge dependence
is discussed in detail for the 1/(m k) term in the potential. Matching on-shell
gives a 1/(m k) potential that is gauge independent and does not vanish for
QED.

</DOC>
<DOC>
<DOCNO> 8807 </DOCNO>
Effects of finite curvature on soliton dynamics in a chain of nonlinear


  We consider a curved chain of nonlinear oscillators and show that the
interplay of curvature and nonlinearity leads to a number of qualitative
effects. In particular, the energy of nonlinear localized excitations centered
on the bending decreases when curvature increases, i.e. bending manifests
itself as a trap for excitations. Moreover, the potential of this trap is
double-well, thus leading to a symmetry breaking phenomenon: a symmetric
stationary state may become unstable and transform into an energetically
favorable asymmetric stationary state. The essentials of symmetry breaking are
examined analytically for a simplified model. We also demonstrate a threshold
character of the scattering process, i.e. transmission, trapping, or reflection
of the moving nonlinear excitation passing through the bending.

</DOC>
<DOC>
<DOCNO> 152394 </DOCNO>
Fivebranes Wrapped On Associative Three-Cycles


  We construct supergravity solutions corresponding to fivebranes wrapping
associative three-cycles of constant curvature in manifolds of G_2-holonomy.
The solutions preserve 2 supercharges and are first constructed in D=7 gauged
supergravity and then lifted to D=10,11. We show that the low-energy theory of
M-fivebranes wrapped on a compact hyperbolic three-space is dual to a
superconformal field theory in D=3 by exhibiting a flow to an AdS_4 region. For
IIB-fivebranes wrapped on a three-sphere we speculate on a connection with
spontaneous supersymmetry breaking of pure N=1 super Yang-Mills theory in D=3.

</DOC>
<DOC>
<DOCNO> 121381 </DOCNO>
Slow Jets in Seyfert Galaxies: NGC 1068


  We have used the Very Long Baseline Array at 5 GHz to image the nucleus of
NGC 1068 at two epochs separated by 2.92 yr. No relative motion was detected
between the high brightness-temperature knots within components NE and C
relative to the nuclear component S1, placing an upper limit of 0.075 c on the
relative component speeds at distances of 21 pc and 43 pc from the AGN. The low
speed is consistent with the low bulk flow speed previously inferred from
indirect arguments based on ram pressure at the bow shock and on line emission
from the jet-cloud collision at cloud C. The components are probably shocks in
the jet, and the bulk flow speed could conceivably be higher than the limit
reported here.

</DOC>
<DOC>
<DOCNO> 10108 </DOCNO>
Statistical Mechanics for States with Complex Eigenvalues and


  Statistical mechanics for states with complex eigenvalues, which are
described by Gel'fand triplet and represent unstable states like resonances,
are discussed on the basis of principle of equal ${\it a priori}$ probability.
A new entropy corresponding to the freedom for the imaginary eigenvalues
appears in the theory. In equilibriums it induces a new physical observable
which can be identified as a common time scale. It is remarkable that in spaces
with more than 2 dimensions we find out existence of stable and quasi-stable
systems, even though all constituents are unstable. In such systems all
constituents are connected by stationary flows which are generally observable
and then we can say that they are semiclassical systems. Examples for such
semiclassical systems are constructed in parabolic potential barriers. The
flexible structure of the systems is also pointed out.

</DOC>
<DOC>
<DOCNO> 119795 </DOCNO>
On the Critical Mass: the case of white dwarfs


  We recall the generalization of the Feynman-Metropolis-Teller approximation
for a compressed atom using a relativistic Fermi-Thomas model. These results
within a Wigner-Seitz approximation lead to a new equation of state for white
dwarfs and to a new value of their critical mass, smaller than the one obtained
by Chandrasekhar. The possible observations of these effects in binary neutron
stars are outlined.

</DOC>
<DOC>
<DOCNO> 67780 </DOCNO>
Final state interaction in heavy hadron decay


  I present a critical account of the final-state interaction (FSI) in two-body
B decays from viewpoint of the hadron picture. I emphasize that the phase and
the magnitude of decay amplitude are related to each other by a dispersion
relation. In a model phase of FSI motivated by experiment, I illustrate how
much the magnitude of amplitude can deviate from its factorization value by the
FSI.

</DOC>
<DOC>
<DOCNO> 121180 </DOCNO>
Analysis of resonances in grand design spiral galaxies


  We have searched for corotations (CR) in three Southern grand design spiral
galaxies: NGC 1365, NGC 1566 and NGC 2997. We have also introduced a method of
quantifying errors in the phase diagram used to detect CR. We established the
m=2 pattern CR at 12.1 kpc, 9.4 kpc and 7 kpc, for NGC 1365, NGC 1566 and NGC
2997, respectively. By using published rotation curves, we could determine
spiral pattern angular speeds of 25.0 km/sec/kpc, 12.2 km/sec/kpc and 17.6
km/sec/kpc, respectively. A three armed component has been detected in NGC
2997, with the CR placed at 8.7 kpc with a pattern angular speed
Omega_{CR_3}=12.7 km/sec/kpc. An m=1 component was detected in NGC 1566. We
warily locate the CR at 7.1 kpc, with a pattern angular speed Omega_{CR}
approx. 16.6 km/sec/kpc. This pattern does not present ILR. Ages have been
determined by studying the radial density profile of the m=2 Fourier components
in g (newly formed stars) and i (perturbing SDW supported by the disk of old
stars), aided by the global aspect of the real spiral pattern in comparison
with numerical simulations. The pattern is approx. 1200 Myr old in NGC 1365,
approx. 800 Myr old in NGC 1566 and younger than 80 Myr in NGC 2997.

</DOC>
<DOC>
<DOCNO> 100581 </DOCNO>
Orbifold Quantum Cohomology


  This is a research announcement of the theory of orbifold quantum cohomology.

</DOC>
<DOC>
<DOCNO> 100425 </DOCNO>
Lines on Non-degenerate Surfaces


  On an affine variety $X$ defined by homogeneous polynomials, every line in
the tangent cone of $X$ is a subvariety of $X$. However there are many other
germs of analytic varieties which are not of cone type but contain ``lines''
passing through the origin. In this paper, we give a method to determine the
existence and the ``number'' of such lines on non-degenerate surface
singualrities.

</DOC>
<DOC>
<DOCNO> 122095 </DOCNO>
Radio polarization from the inner Galaxy at arcminute resolution


  The Southern Galactic Plane Survey (SGPS) is an HI and 1.4-GHz continuum
survey of the 4th quadrant of the Galaxy at arcmin resolution. We present here
results on linearly polarized continuum emission from an initial
28-square-degree Test Region for the SGPS, consisting of 190 mosaiced pointings
of the Australia Telescope Compact Array, and covering the range 325.5 < l <
332.5, -0.5 < b < +3.5. Complicated extended structure is seen in linear
polarization throughout the Test Region, almost all of which has no correlation
with total intensity. We interpret the brightest regions of polarized emission
as representing intrinsic structure in extended polarization, most likely
originating in the Crux spiral arm at a distance of 3.5 kpc; fainter polarized
structure is imposed by Faraday rotation in foreground material. Two large
areas in the field are devoid of polarization. We argue that these voids are
produced by foreground HII regions in which the magnetic field is disordered on
scales of ~0.1-0.2 pc. We also identify a depolarized halo around the HII
region RCW 94, which we suggest results from the interaction of the HII region
with a surrounding molecular cloud.

</DOC>
<DOC>
<DOCNO> 118617 </DOCNO>
Atomic Carbon in Galaxies


  We present new measurements of the ground state fine-structure line of atomic
carbon at 492 GHz in a variety of nearby external galaxies, ranging from spiral
to irregular, interacting and merging types. In comparison with CO(1-0), the
CI(1-0) intensity stays fairly comparable in the different environments, with
an average value of the ratio of the line integrated areas in Kkm/s of
CI(1-0)/CO(1-0) = 0.2 +/- 0.2. However, some variations can be found within
galaxies, or between galaxies. Relative to CO lines, CI(1-0) is weaker in
galactic nuclei, but stronger in disks, particularly outside star forming
regions. Also, in NGC 891, the CI(1-0) emission follows the dust continuum at
1.3mm extremely well along the full length of the major axis where molecular
gas is more abundant than atomic gas. Atomic carbon therefore appears to be a
good tracer of molecular gas in external galaxies, possibly more reliable than
CO. Atomic carbon can contribute significantly to the thermal budget of
interstellar gas. Cooling due to C and CO amounts typically to 2 x 10^{-5} of
the FIR continuum or 5% of the CII line. However, C and CO cooling reaches 30%
of the gas total, in Ultra Luminous InfraRed Galaxies, where CII is abnormally
faint. Together with CII/FIR, the emissivity ratio CI(1-0)/FIR can be used as a
measure of the non-ionizing UV radiation field in galaxies.

</DOC>
<DOC>
<DOCNO> 101011 </DOCNO>
A note on an alleged proof of the relative consistency of P=NP with PA


  We indicate that an argument of da Costa and Doria in fact proves P=NP. This
observation makes their argument appear dubious. We isolate a weak version of
one of their lemmas which would already prove P=NP. We point out that even this
weak version is probably false. In fact, a generalized form of this weak
version is provably false.

</DOC>
<DOC>
<DOCNO> 71234 </DOCNO>
Renormalons and Power Corrections


  Even for short-distance dominated observables the QCD perturbation expansion
is never complete. The divergence of the expansion through infrared renormalons
provides formal evidence of this fact. In this article we review how this
apparent failure can be turned into a useful tool to investigate power
corrections to hard processes in QCD.

</DOC>
<DOC>
<DOCNO> 151835 </DOCNO>
Vertex Operators for the Supermembrane and Background Field Matrix


  We derive the vertex operators that are expected to govern the emission of
the massless d=11 supermultiplet from the supermembrane in the light cone
gauge. Our results immediately imply the linear coupling of matrix theory to an
arbitrary supergravity background to all orders in anticommuting coordinates.
Finally we address the definition of n-point tree level and one-loop scattering
amplitudes. The resulting 3-point tree level amplitudes turn out to agree with
d=11 supergravity and are completely fixed by supersymmetry and the existence
of a normalizable ground state.

</DOC>
<DOC>
<DOCNO> 40431 </DOCNO>
Experimental results on hadronic c decays


  Recent results involving hadronic decays of charmed mesons and baryons are
reviewed. Information relevant to decay mechanisms and to light quark scalar
mesons is discussed.

</DOC>
<DOC>
<DOCNO> 40545 </DOCNO>
The CRESST Experiment: Recent Results and Prospects


  The CRESST experiment seeks hypothetical WIMP particles that could account
for the bulk of dark matter in the Universe. The detectors are cryogenic
calorimeters in which WIMPs would scatter elastically on nuclei, releasing
phonons. The first phase of the experiment has successfully deployed several
262 g sapphire devices in the Gran Sasso underground laboratories. A main
source of background has been identified as microscopic mechanical fracturing
of the crystals, and has been eliminated, improving the background rate by up
to three orders of magnitude at low energies, leaving a rate close to one count
per day per kg and per keV above 10 keV recoil energy. This background now
appears to be dominated by radioactivity, and future CRESST scintillating
calorimeters which simultaneously measure light and phonons will allow
rejection of a great part of it.

</DOC>
<DOC>
<DOCNO> 100700 </DOCNO>
A PT-Invariant Potential With Complex QES Eigenvalues


  We show that the quasi-exactly solvable eigenvalues of the Schr\"odinger
equation for the PT-invariant potential $V(x) = -(\zeta \cosh 2x -iM)^2$ are
complex conjugate pairs in case the parameter M is an even integer while they
are real in case M is an odd integer. We also show that whereas the PT symmetry
is spontaneously broken in the former case, it is unbroken in the latter case.

</DOC>
<DOC>
<DOCNO> 116986 </DOCNO>
Measurement and Correction of Cross-Plane Coupling in Transport Lines


  In future linear colliders the luminosity will depend on maintaining the
small emittance aspect ratio delivered by damping rings. Correction of
cross-plane coupling can be important in preventing dilution of the beam
emittance. In order to minimize the vertical emittance, especially for a flat
beam, it is necessary to remove all cross-plane (x-y) correlations. This paper
studies emittance measurement and correction for coupled beams in the presence
of realistic measurement errors. The results of simulations show that
reconstruction of the full 4x4 beam matrix can be misleading in the presence of
errors. We suggest more robust tuning procedures for minimizing linear
coupling.

</DOC>
<DOC>
<DOCNO> 84614 </DOCNO>
Black hole solutions in Euler-Heisenberg theory


  We construct static and spherically symmetric black hole solutions in the
Einstein-Euler-Heisenberg (EEH) system which is considered as an effective
action of a superstring theory. We considered electrically charged,
magnetically charged and dyon solutions. We can solve analytically for the
magnetically charged case. We find that they have some remarkable properties
about causality and black hole thermodynamics depending on the coupling
constant of the EH theory $a$ and $b$, though they have central singularity as
in the Schwarzschild black hole.

</DOC>
<DOC>
<DOCNO> 121309 </DOCNO>
Doppler Tomography of Dwarf Nova IY UMa during Quiescence


  Quiescent Doppler tomography of the newly discovered deeply-eclipsing SU UMa
system IY UMa reveals properties of the region where the accretion stream from
the donor impacts the edge of the disc. A very strong bright spot is produced
and the Keplerian disc emission in the impact region is disrupted or obscured.
The differing properties of Halpha, Hbeta and He I emission will allow physical
parameters of the converging flow region to be studied.

</DOC>
<DOC>
<DOCNO> 116637 </DOCNO>
Whence the Gauge Fields arise


  A gauge fields (and massive, too) arise from the production of the
probability by the spinors.

</DOC>
<DOC>
<DOCNO> 69744 </DOCNO>
How do Neutrinos Propagate ? - Wave-Packet Treatment of Neutrino


  The wave-packet treatment of neutrino oscillation developed previously is
extended to the case in which momentum distribution functions are taken to be a
Gaussian form with both central values and dispersions depending on the mass
eigenstates of the neutrinos. It is shown among other things that the velocity
of the neutrino wave packets does not in general agree with what one would
expect classically and that relativistic neutrinos emitted from pions
nevertheless do follow, to a good approximation, the classical trajectory.

</DOC>
<DOC>
<DOCNO> 7999 </DOCNO>
Reaction-controlled diffusion


  The dynamics of a coupled two-component nonequilibrium system is examined by
means of continuum field theory representing the corresponding master equation.
Particles of species A may perform hopping processes only when particles of
different type B are present in their environment. Species B is subject to
diffusion-limited reactions. If the density of B particles attains a finite
asymptotic value (active state), the A species displays normal diffusion. On
the other hand, if the B density decays algebraically ~t^{-a} at long times
(inactive state), the effective attractive A-B interaction is weakened. The
combination of B decay and activated A hopping processes gives rise to
anomalous diffusion, with mean-square displacement < x_A(t)^2 > ~ t^{1-a} for a
< 1. Such algebraic subdiffusive behavior ensues for n-th order B annihilation
reactions (n B -> 0) with n >=3, and n = 2 for d < 2. The mean-square
displacement of the A particles grows only logarithmically with time in the
case of B pair annihilation (n = 2) and d >= 2 dimensions. For radioactive B
decay (n = 1), the A particles remain localized. If the A particles may hop
spontaneously as well, or if additional random forces are present, the A-B
coupling becomes irrelevant, and conventional diffusion is recovered in the
long-time limit.

</DOC>
<DOC>
<DOCNO> 9894 </DOCNO>
Hole superconductivity from kinetic energy gain


  The apparently unrelated experimental observations of optical sum rule
violation[1] and of tunneling asymmetry in NIS tunneling[2] find a simple
explanation within the theory of hole superconductivity. In fact, both
phenomena were predicted by the theory long before they were experimentally
observed[3,4]. Other experimental predictions of the theory, in particular a
novel feature expected in photoemission experiments, are discussed.

</DOC>
<DOC>
<DOCNO> 68012 </DOCNO>
Effective Dual Higgs Mechanism with Confining Forces


  We consider the dual Yang-Mills theory which shows some kind of confinement
at large distances. In the static system of the test color charges an analytic
expression for the string tension is derived.

</DOC>
<DOC>
<DOCNO> 10743 </DOCNO>
Critical Velocity of Superfluid Flow past Large Obstacles in


  By considering the stability of potential flow of a superfluid around large
obstacles of size R, we derive an analytical result for the critical velocity
which is of order v_c \sim \hbar / mR, scaling inversely with obstacle size, in
contrast to what is obtained from a Landau criterion. Our results are compared
with numerical solutions of the Gross-Pitaevskii equation and with recent
measurements of the critical velocity in Bose-Einstein condensates of dilute
atomic gases.

</DOC>
<DOC>
<DOCNO> 100259 </DOCNO>
Line bundles of type (1,,,1,2,,,2,4,,,4) on Abelian Varieties


  We show birationality of the morphism associated to line bundles $L$ of type
$(1,...,1,2,...,2,4,...,4)$ on a generic $g-$dimensional abelian variety into
its complete linear system such that $h^0(L)=2^g$. When $g=3$, we describe the
image of the abelian threefold and from the geometry of the moduli space
$SU_C(2)$ in the linear system $|2\theta_C|$, we obtain analogous results in
$\p H^0(L)$.

</DOC>
<DOC>
<DOCNO> 100691 </DOCNO>
More About All Current-Algebraic Orbifolds


  Recently a construction was given for the stress tensors of all sectors of
the general current-algebraic orbifold A(H)/H, where A(H) is any
current-algebraic conformal field theory with a finite symmetry group H. Here
we extend and further analyze this construction to obtain the mode formulation
of each sector of each orbifold A(H)/H, including the twisted current algebra,
the Virasoro generators, the orbifold adjoint operation and the commutator of
the Virasoro generators with the modes of the twisted currents. As
applications, general expressions are obtained for the twisted current-current
correlator and ground state conformal weight of each twisted sector of any
permutation orbifold A(H)/H, H \subset S_N. Systematics are also outlined for
the orbifolds A(Lie h(H))/H of the (H and Lie h)-invariant conformal field
theories, which include the general WZW orbifold and the general coset
orbifold. Finally, two new large examples are worked out in further detail: the
general S_N permutation orbifold A(S_N)/S_N and the general inner-automorphic
orbifold A(H(d))/H(d).

</DOC>
<DOC>
<DOCNO> 122718 </DOCNO>
Radio Observations of a Galactic Extended Source


  The radio images from the Parkes-MIT-NRAO (PMN) Southern Sky Survey at 4850
MHz have revealed a number of previously unknown radio sources. One such source
has been observed using the multi-frequency capabilities of the Australia
Telescope Compact Array (ATCA) at frequencies of 1380 MHz and 2378 MHz. Further
observations of the source were made using the Molonglo Observatory Synthesis
Telescope (MOST) at a frequency of 843 MHz. We present the reduced
multi-frequency observations of this source and provide a brief description of
the source properties.

</DOC>
<DOC>
<DOCNO> 116436 </DOCNO>
Theory of Complex Scattering Lengths


  We derive a generalized Low equation for the T-matrix appropriate for complex
atom-molecule interaction. The properties of this new equation at very low
energies are studied and the complex scattering length and effective range are
derived.

</DOC>
<DOC>
<DOCNO> 68854 </DOCNO>
Higgs Boson Searches at LEP Up To sqrt(s) = 202 GeV


  The latest preliminary combined results of the Higgs boson searches from the
LEP experiments ALEPH, DELPHI, L3 and OPAL are presented. A general scan of the
MSSM parameters is performed and leads to stringent lower mass limits and for
the first time excludes low tan(beta) values.

</DOC>
<DOC>
<DOCNO> 7707 </DOCNO>
Effects of Dense Matter on Hadron Production in Heavy-Ion Collisions


  The intrinsic transverse momentum distribution of partons in the nucleon can
be used to explain a large amount of high-$p_T$ hadron and photon production
data in high-energy nucleon-nucleon collisions at energies $\sqrt{s} \approx
20$ to 1800 GeV. However, proton-nucleus experiments at energies $\approx 30$
GeV show an extra enhancement (Cronin effect) in the yield of photons and
mesons compared to a simple extrapolation of the proton-proton data. This
enhancement is due to the effect of the dense hadronic matter encountered by
the projectile proton in the nuclear environment. We discuss the origin and the
properties of the nuclear enhancement.

</DOC>
<DOC>
<DOCNO> 11205 </DOCNO>
Competition of charge, orbital, and ferromagnetic correlations in


  The competition of charge, orbital, and ferromagnetic interactions in layered
manganites is investigated by magneto-Raman scattering spectroscopy. We find
that the colossal magnetoresistance effect in the layered compounds results
from the interplay of the orbital and ferromagnetic double-exchange
correlations. Inelastic scattering by charge-order fluctuations dominates the
quasiparticle dynamics in the ferromagnetic-metal state. The scattering is
suppressed at low frequencies, consistent with the opening of a charge-density
wave pseudogap.

</DOC>
<DOC>
<DOCNO> 151554 </DOCNO>
D-particle polarizations with multipole moments of higher-dimensional


  We study the polarization states of the D0-brane in type IIA string theory.
In addition to states with angular momentum and magnetic dipole moments, there
are polarization states of a single D0-brane with nonzero D2-brane dipole and
magnetic H-dipole moments, as well as quadrupole and higher moments of various
charges. These fundamental moments of the D0-brane polarization states can be
determined directly from the linearized couplings of background fields to the
D0-brane world-volume fermions. These couplings determine the long range
supergravity fields produced by a general polarization state, which typically
have non-zero values for all the bosonic fields of type IIA supergravity. We
demonstrate the precise cancellation between spin-spin and magnetic
dipole-dipole interactions and an analogous cancellation between 3-form and
H-field dipole-dipole interactions for a pair of D0-branes. The first of these
cancellations follows from the fact that spinning D0-brane states have
gyromagnetic ratio g = 1, and the second follows from the fact that the ratio
between the 3-form and H-field dipole moments is also 1 in natural units. Both
of these relationships can be seen immediately from the couplings in the
D0-brane world-volume action.

</DOC>
<DOC>
<DOCNO> 101324 </DOCNO>
Bicategories of operator algebras and Poisson manifolds


  It is well known that rings are the objects of a bicategory, whose arrows are
bimodules, composed through the bimodule tensor product. We give an analogous
bicategorical description of C*-algebras, von Neumann algebras, Lie groupoids,
symplectic groupoids, and Poisson manifolds. The upshot is that known
definitions of Morita equivalence for any of these cases amount to isomorphism
of objects in the pertinent bicategory.

</DOC>
<DOC>
<DOCNO> 99611 </DOCNO>
Concrete Fock representations of Mickelsson-Faddeev-like algebras


  The Mickelsson-Faddeev (MF) algebra can naturally be embedded in a non-Lie
algebra, which suggests that it has no Fock representations. The difficulties
are due to the inhomogeneous term in the connection's transformation law.
Omitting this term yields a ``classical MF algebra'', which has other abelian
extensions that do possess Fock modules. I explicitly construct such modules
and the intertwining action of the higher-dimensional Virasoro algebra.

</DOC>
<DOC>
<DOCNO> 70252 </DOCNO>
Higgs production at hadron colliders as a probe of new physics


  The coupling of Higgs with gauge bosons can receive non-decoupling
corrections due to heavy quanta. Deviation from the SM predictions are
described by a set of parameters e_V, which can be related to the parameters
S,T. The Higgs production by gluon fusion can be used to probe e_g, whereas its
decays into WW can probe e_W. The resulting bounds may imply the exclusion of
heavy particles, such as additional standard or mirror families, chiral colored
sextets and octet quarks. Within the MSSM, we also find that gluon fusion is a
sensitive probe for the spectrum of squark masses.

</DOC>
<DOC>
<DOCNO> 119574 </DOCNO>
On Young Neutron Stars as Propellers and Accretors with Conventional


  The similarity of rotation periods of, the anomalous X-ray pulsars (AXPs),
the soft gamma ray repeaters (SGRs) and the dim thermal neutron stars (DTNs)
suggests a common mechanism with an asymptotic spindown phase through the
propeller and early accretion stages. The DTNs are in the propeller stage.
Their luminosities arise from frictional heating in the neutron star. If the
8.4 s rotation period of the DTN RXJ 0720.4-3125 is close to its rotational
equilibrium period, the propeller torque indicates a magnetic field in the
10$^{12}$ Gauss range. The mass inflow rate onto the propeller is of the order
of the AXP accretion rates. The limited range of rotation periods, taken to be
close to equilibrium periods, and magnetic fields in the range 5 E11- 5 E12
Gauss correspond to mass inflow rates 3.2 E14 gm/s < \dot{M} < 4.2 E17 gm/s.
Observed spindown rates of the AXPs and SGRs also fit in with these fields
rather than magnetar fields periods. The source of the mass inflow is a remnant
accretion disk formed as part of the fallback during the supernova explosion.
These classes of sources thus represent the alternative pathways for those
neutron stars that do not become radio pulsars. For the highest mass inflow
rates the propeller action may support enough circumstellar material so that
the optical thickness to electron scattering destroys the X-ray beaming, and
the rotation period is not observable. These are the radio quiet neutron stars
(RQNSs) at the centers of supernova remnants Cas A, Puppis A, RCW 103 and
296.5+10.

</DOC>
<DOC>
<DOCNO> 102435 </DOCNO>
Some identification problems for integro-differential operator equations


  We consider, in a Hilbert space $H$, the convolution integro-differential
equation $u''(t)-h*Au(t)=f(t)$, $0\le t\le T$, $h*v(t)=\int_0^t h(t-s)v(s) ds$,
where $A$ is a linear closed densely defined (possibly selfadjoint and/or
positive definite) operator in $H$. Under suitable assumptions on the data we
solve the inverse problem consisting of finding the kernel $h$ from the extra
data (measured data) of the type $g(t):=(u(t),\phi)$, where $\phi$ is some
eigenvector of $A^*$. An inverse problem for the first-order equation
$u'(t)-l*Au(t)=f(t)$, $0\le t\le T$, is also studied when $A$ enjoys the same
properties as in the previous case.

</DOC>
<DOC>
<DOCNO> 120836 </DOCNO>
The Evolution and Space Density of Damped Lyman-alpha Galaxies


  The results of a new spectroscopic survey of 66 $z \simgt 4$ quasars for
Damped Lyman-alpha absorption systems are presented. The search led to the
discovery of 30 new DLA candidates which are analysed in order to compute the
comoving mass density of neutral gas in a non-zero lambda Universe. The
possible sources of uncertainty are discussed and the implications of our
results for the theories of galaxy formation and evolution are emphasized. A
subsequent paper will present details of the calculations summarised here and a
more extensive explanation of the consequences of our observations for the
understanding of the nature of DLAs.

</DOC>
<DOC>
<DOCNO> 80865 </DOCNO>
Static three quark potential in the quenched lattice QCD


  We study the static three quark potential using lattice QCD simulation. At
zero temperature, the three quark potential is extracted from the baryonic
Wilson loop and fitted to the phenomenological form, the sum of the Coulomb
term, linearly rising term and the constant. We compare two types of the linear
term, ``$Y$'' and ``$\Delta$'' type, and find that the string tension almost
coincide with $\sigma_{Q\bar{Q}}$ in the former case. We also investigate the
three quark potential at finite temperature using the Polyakov loop
correlation. In the deconfined phase, the screened potential is observed
similarly to the case of $Q\bar{Q}$ system.

</DOC>
<DOC>
<DOCNO> 117630 </DOCNO>
Review of Big Bang Nucleosynthesis and Primordial Abundances


  Big Bang Nucleosynthesis (BBN) is the synthesis of the light nuclei,
Deuterium, He3, He4 and Li7, during the first few minutes of the universe. This
review concentrates on recent improvements in the measurement of the primordial
(after BBN, and prior to modification) abundances of these nuclei. We mention
improvement in the standard theory, and the non-standard extensions which are
limited by the data. (abridged)

</DOC>
<DOC>
<DOCNO> 117109 </DOCNO>
'New Theory', 'New Postulates' and the Big Revolution on the Theoretical


  This paper describes a 'New Theory' based on the new concept titled as 'CDM'
(Charge Density Mass) which is a new state of the mass. According to the 'New
Theory', there are basically two types of mass in the universe: Charge Density
Mass (CDM) and Mass Density Mass (MDM), and there is an indirect proportion
between CDM and MDM of the particles and the universe. The Fully Charge Density
Mass (FCDM) state of any particle is considered as the Mass-Less (ML) state of
the particle. The speed of any particle can reach to and can exceed the speed
of light in the state of FCDM (or ML). There is no the fully vacuum in the
universe, the universe consists of CDM and MDM, and the boundary of the
universe is identified by the CDM and MDM of the universe. There were no the
Big Bang and there will not be the Big Crunch in the universe. But, there are
continuously the changes from MDM to CDM and from CDM to MDM in the universe.
In addition, this paper describes seven 'New Postulates' on the structure of
the universe including the structure of the particles and living existences
that can be considered as the big revolution on theoretical physics.

</DOC>
<DOC>
<DOCNO> 10380 </DOCNO>
Spin tunneling and topological selection rules for integer spins


  We present topological interference effects for the tunneling of a single
large spin, which are caused by the symmetry of a general class of magnetic
anisotropies. The interference originates from spin Berry phases associated
with different tunneling paths exposed to the same dynamics. Introducing a
generalized path integral for coherent spin states, we evaluate transition
amplitudes between ground as well as low-lying excited states. We show that
these interference effects lead to topological selection rules and spin-parity
effects for integer spins that agree with quantum selection rules and which
thus provide a generalization of the Kramers degeneracy to integer spins. Our
results apply to the molecular magnets Mn12 and Fe8.

</DOC>
<DOC>
<DOCNO> 71597 </DOCNO>
An improved random matrix model for the chiral phase transition in QCD


  We consider a lattice-inspired random matrix model for the QCD chiral phase
transition at finite chemical potential. Useful features of the usual RMM for
QCD at finite chemical potential are reobtained, some being brought closer to
their lattice equivalent. The simple physical requirement of a vanishing quark
number density in the broken phase is fulfilled in the limit of a large number
of timeslices.
  It is argued that the suppression of the partition function at nonzero
chemical potential in the broken phase, seen in the usual RMM, is possibly
present in lattice simulations and is simply a result of the discretization in
time.

</DOC>
<DOC>
<DOCNO> 118048 </DOCNO>
Fundamental parameters of Galactic luminous OB stars V. The effect of


  We study the effect of microturbulence in the line formation calculations of
H and He lines, in the parameter range typical for O and early B stars. We are
specially interested in its effect on the determination of stellar parameters:
effective temperature, surface gravity and specially on the He abundance. We
find that only HeI lines and HeII 4686 are sensibly affected by
microturbulence, and that models with lower gravities, the ones suitable for
supergiants, are more sensitive to it. We analyze five stars using
microturbulence velocities of 0 and 15 km/s. The parameters obtained for 15
km/s differ from the ones at 0 km/s within the limits of the standard error box
of our analysis. The quality of the line fits only improves for HeI 4471, but
not to the extent of completely solving the so-called dilution effect.
Therefore our conclusion is that microturbulence is affecting the derivation of
stellar parameters, but its effect is comparable to the adopted uncertainties.
Thus it can reduce moderate He overabundances and solve line fit quality
differences, but it cannot explain by itself large He overabundances in O
stars.

</DOC>
<DOC>
<DOCNO> 119178 </DOCNO>
Centrifugal buoyancy as a mechanism for neutron star glitches


  The frequent glitches (sudden increases of the apparent angular velocity)
observed in certain pulsars are generally believed to be attributable to
discontinuous angular momentum transfer to the outer neutron star crust from a
differentially rotating superfluid layer, but the precise mechanism is not
quite elucidated. Most explanations invoke vortex pinning as the essential
mechanism responsible for the build up of strain in the crust that is relaxed,
either by fracture of the solid structure or by discontinous unpinning, during
the glitch. It is shown here that there is another mechanism that could give
rise to strain, and subsequent fracture, of the solid crust, even if vortex
pinning is ineffective: this is the effective force arising from the deficit of
centrifugal buoyancy that will be present whenever there is differential
rotation. This centrifugal buoyancy deficit force will be comparable in order
of magnitude, but opposite in direction, to the force that would arise from
vortex pinning if it were effective.

</DOC>
<DOC>
<DOCNO> 118136 </DOCNO>
The intragroup medium in loose groups of galaxies


  We have used the ROSAT PSPC to study the properties of a sample of 24 X-ray
bright galaxy groups, representing the largest sample examined in detail to
date. Hot plasma models are fitted to the spectral data to derive temperatures,
and modified King models are used to characterise the surface brightness
profiles. In agreement with previous work, we find evidence for the presence of
two components in the surface brightness profiles. The extended component is
generally found to be much flatter than that observed in galaxy clusters, and
there is evidence that the profiles follow a trend with system mass. We derive
relationships between X-ray luminosity, temperature and optical velocity
dispersion. The relation between X-ray luminosity and temperature is found to
be L_X \propto T^{4.9}, which is significantly steeper than the same relation
in galaxy clusters. These results are in good agreement with preheating models,
in which galaxy winds raise the internal energy of the gas, inhibiting its
collapse into the shallow potential wells of poor systems.

</DOC>
<DOC>
<DOCNO> 100583 </DOCNO>
A combinatorial property of generic immersions of curves


  A divide is a relative generic immersion of a finite union of copies of the
unit interval in the unit disk. A divide defines a classical link in the 3-
sphere, which is a fibered link if the image of the immersion is connected. We
prove in this paper, that the Lefschetz number of the monodromy is 0. This
result was known for divides, which correspond to real morsifications of
complexe plane curve singularities. The proof uses the space of gradient lines
of a morse function.

</DOC>
<DOC>
<DOCNO> 116433 </DOCNO>
Nonlinear Modes of Liquid Drops as Solitary Waves


  The nolinear hydrodynamic equations of the surface of a liquid drop are shown
to be directly connected to Korteweg de Vries (KdV, MKdV) systems, giving
traveling solutions that are cnoidal waves. They generate multiscale patterns
ranging from small harmonic oscillations (linearized model), to nonlinear
oscillations, up through solitary waves. These non-axis-symmetric localized
shapes are also described by a KdV Hamiltonian system. Recently such ``rotons''
were observed experimentally when the shape oscillations of a droplet became
nonlinear. The results apply to drop-like systems from cluster formation to
stellar models, including hyperdeformed nuclei and fission.

</DOC>
<DOC>
<DOCNO> 9013 </DOCNO>
Impurity-induced dephasing of Andreev states


  A study is presented concerning the influence of flicker noise in the
junction transparency on coherent transport in Andreev states. The amount of
dephasing is estimated for a microwave-activated quantum interferometer.
Possibilities of experimentally investigating the coupling between a
superconducting quantum point contact and its electromagnetic environment are
discussed.

</DOC>
<DOC>
<DOCNO> 71912 </DOCNO>
Color degrees of freedom in nuclear collisions and charmonium


  In high energy nuclear collisions, the Glauber model is commonly used to
evaluate $J/\psi$ suppression due to inelastic interaction with colorless bound
nucleons. This requires an effective value for the $J/\psi$-nucleon absorption
cross section which is larger than theoretically expected. On the other hand,
multiple nucleon-nucleon collisions mediated by color exchange interactions,
excite their color degrees of freedom. We investigate the importance of this
effect and conclude that the related corrections are important to explain the
effective value extrapolated from experiment.

</DOC>
<DOC>
<DOCNO> 122683 </DOCNO>
FUSE Observations of Atomic Abundances and Molecular Hydrogen in the


  We present Far Ultraviolet Spectroscopic Explorer observations of the atomic
and molecular absorption in high velocity cloud HVC 287.5+22.5+240, which lies
in front of the ultraviolet-bright nucleus of the Seyfert 1 galaxy NGC 3783. We
detect H2, N I, N II, Si II, and Fe II absorption and set limits on the amount
of absorption due to P III, Ar I, and Fe III. We extend the earlier metallicity
and dust-depletion measurements made by Lu and collaborators by examining the
relative gas-phase abundances of Si, P, S, and Fe. Corrections to the derived
gas-phase abundances due to ionized gas in the HVC are less than 15%. The HVC
has a metallicity of 0.2-0.4 solar, similar to that of the Small Magellanic
Cloud. The relative abundance pattern for the elements studied resembles that
of warm gas in the SMC, which supports the idea that this HVC is part of the
tidally stripped Leading Arm of the Magellanic Stream. The abundance pattern
implies that the HVC contains dust grains that have been processed
significantly. It is likely that the grain mantles have been modified or
stripped back to expose the grain cores. We have identified more than 30 lines
of H2 arising in the HVC from rotational levels J = 0 to J = 3. Synthetic
spectra and a curve-of-growth fit to these lines with b = 12 km/sec indicate
that log N(H2) = 16.80+/-0.10 and f(H2) = 2N(H2)/[N(H I)+2N(H2)] = 0.0016. From
an analysis of the H2 rotational populations, we find an absorption rate (at
1000 A) that is less than one-tenth the average value in the solar
neighborhood. The presence of molecular gas in the HVC requires that either the
H2 formed in situ or that molecules formed within the SMC survived tidal
stripping. We favor the latter possibility because of the long formation time
derived for molecules in this HVC.

</DOC>
<DOC>
<DOCNO> 119472 </DOCNO>
Instabilities and Clumping in Type Ia Supernova Remnants


  We present two-dimensional high-resolution hydrodynamical simulations in
spherical polar coordinates of a Type Ia supernova interacting with a constant
density interstellar medium. The ejecta are assumed to be freely expanding with
an exponential density profile. The interaction gives rise to a double-shocked
structure susceptible to hydrodynamic instabilities. The Rayleigh-Taylor
instability initially grows, but the Kelvin-Helmholtz instability takes over,
producing vortex rings. The nonlinear instability initially evolves toward
longer wavelengths and eventually fades away when the reverse shock front is in
the flatter part of the supernova density distribution. Based on observations
of X-ray knots and the protrusion in the southeast outlin of Tycho's supernova
remnant, we include clumping in the ejecta. The clump interaction with the
reverse shock induces Rayleigh-Taylor and Kelvin-Helmholtz instabilities on the
clump surface that facilitate fragmentation. In order to survive crushing and
to have a bulging effect on the forward shock, the clump's initial density
ratio to the surrounding ejecta must be at least 100 for the conditions in
Tycho's remnant. The 56Ni bubble effect may be important for the development of
clumpiness in the ejecta. The observed presence of an Fe clump would then
require a non-radioactive origin for this Fe, possibly 54Fe. The large radial
distance of the X-ray emitting Si and S ejecta from the remnant center
indicates that they were initially in clumps.

</DOC>
<DOC>
<DOCNO> 70456 </DOCNO>
Pairs of charged heavy-leptons from an SU(3) X U(1) model at CERN LHC


  One of the versions of the SU(3)$_L\otimesU(1)_N$ electroweak model predicts
charged heavy-leptons which do not belong to any class of heavy-leptons
proposed up to now. We investigate the production and signatures of pairs of
these heavy-leptons {\it via} the Drell-Yan process and the gluon-gluon fusion
at the CERN Large Hadron Collider (LHC). As an example we study the decay of
the exotic leptons into another ones. We see that the lifetime of the exotic
leptons can be short.

</DOC>
<DOC>
<DOCNO> 120276 </DOCNO>
The correlation between black hole mass and bulge velocity dispersion in


  Recent work has demonstrated that there is a tight correlation between the
mass of a black hole and the velocity dispersion of the bulge of its host
galaxy. We show that the model of Kauffmann & Haehnelt, in which bulges and
supermassive black holes both form during major mergers, produces a correlation
between M_bh and sigma with slope and scatter comparable to the observed
relation. In the model, the M_bh - sigma relation is significantly tighter than
the correlation between black hole mass and bulge luminosity or the correlation
between bulge luminosity and velocity dispersion. There are two reasons for
this: i) the gas masses of bulge progenitors depend on the velocity dispersion
but not on the formation epoch of the bulge, whereas the stellar masses of the
progenitors depend on both; ii) mergers between galaxies move black holes along
the observed M_bh - sigma relation, even at late times when the galaxies are
gas-poor and black holes grow mainly by merging of pre-existing black holes. We
conclude that the small scatter in the observed M_bh - sigma relation is
consistent with a picture in which bulges and black holes form over a wide
range in redshift.

</DOC>
<DOC>
<DOCNO> 99450 </DOCNO>
Hall-Littlewood vertex operators and generalized Kostka polynomials


  A family of vertex operators that generalizes those given by Jing for the
Hall-Littlewood symmetric functions is presented. These operators produce
symmetric functions related to the Poincare polynomials referred to as
generalized Kostka polynomials in the same way that Jing's operator produces
symmetric functions related to Kostka-Foulkes polynomials. These operators are
then used to derive commutation relations and new relations involving the
generalized Kostka coefficients. Such relations may be interpreted as
identities in the (GL(n) x C^*)-equivariant K-theory of the nullcone.

</DOC>
<DOC>
<DOCNO> 150696 </DOCNO>
The Spacetime Life of a Non-BPS D-particle


  We investigate the classical geometry generated by a stable non-BPS
D-particle. We consider the boundary state of a stable non-BPS D-particle in
the covariant formalism in the type IIB theory orbifolded by (-1)^{F_L} I_4. We
calculate the scattering amplitude between two D-particles in the non-compact
and compact orbifold and analyse the short and long distance behaviour. At
short distances we find no force at order $v^2$ for any radius, and at the
critical radius we find a BPS-like behaviour up to $v^4$ corrections for long
and short distances. Projecting the boundary state on the massless states of
the orbifold closed string spectrum we obtain the large distance behaviour of
the classical solution describing this non-BPS D-particle in the non-compact
and compact cases. By using the non-BPS D-particle as a probe of the background
geometry of another non-BPS D-particle, we recover the no-force condition at
the critical radius and the $v^2$ behaviour of the probe. Moreover, assuming
that the no-force persists for the complete geometry we derive part of the
classical solution for the non-BPS D-particle.

</DOC>
<DOC>
<DOCNO> 150544 </DOCNO>
Noether Currents for Bosonic Branes


  We consider a relativistic brane propagating in Minkowski spacetime described
by any action which is local in its worldvolume geometry. We examine the
conservation laws associated with the Poincar\'e symmetry of the background
from a worldvolume geometrical point of the view. These laws are exploited to
explore the structure of the equations of motion. General expressions are
provided for both the linear and angular momentum for any action depending on
the worldvolume extrinsic curvature. The conservation laws are examined in
perturbation theory. It is shown how non-trivial solutions with vanishing
energy-momentum can be constructed in higher order theories. Finally,
subtleties associated with boundary terms are examined in the context of the
brane Einstein-Hilbert action.

</DOC>
<DOC>
<DOCNO> 116599 </DOCNO>
Melting behavior of large disordered sodium clusters


  The melting-like transition in disordered sodium clusters Na_N, with N=92 and
142 is studied by using a first-principles constant-energy molecular dynamics
simulation method. Na_142, whose atoms are distributed in two (surface and
inner) main shells with different radial distances to the center of mass of the
cluster, melts in two steps: the first one, at approx. 130 K, is characterized
by a high intrashell mobility of the atoms, and the second, homogeneous
melting, at approx. 270 K, involves diffusive motion of all the atoms across
the whole cluster volume (both intrashell and intershell displacements are
allowed). On the contrary, the melting of Na_92 proceeds gradually over a very
wide temperature interval, without any abrupt step visible in the thermal or
structural melting indicators. The occurrence of well defined steps in the
melting transition is then shown to be related to the existence of a
distribution of the atoms in shells. Thereby we propose a necessary condition
for a cluster to be considered rigorously amorphouslike (totally disordered),
namely that there are no space regions of the cluster where the local value of
the atomic density is considerably reduced. Na_92 is the only cluster from the
two considered that verifies this condition, so its thermal behavior can be
considered as representative of that expected for amorphous clusters. Na_142,
on the other hand, has a discernible atomic shell structure and should be
considered instead as just partially disordered. The thermal behavior of these
two clusters is also compared to that of icosahedral (totally ordered) sodium
clusters of the same sizes.

</DOC>
<DOC>
<DOCNO> 71518 </DOCNO>
Constraints on ultraviolet-stable fixed points in supersymmetric gauge


  We consider the possibility that some supersymmetric gauge theories which are
not asymptotically free can be governed by ultraviolet-stable fixed points. If
this scenario can be realized, gaugino masses will exhibit power-law running
with scale, providing a possible solution to the supersymmetric flavor problem.
While naive perturbative calculations hint at the appearance of
ultraviolet-stable fixed points in certain theories, there are strong
constraints following from limits on the scaling dimensions of gauge-invariant
operators, positivity of central charges, and Cardy's conjectured constraint on
the flow of the Euler coefficient in the stress tensor trace anomaly. Also, we
prove that if ultraviolet-stable fixed points do exist, they cannot occur in
the perturbative regime of a renormalizable model, and that all-orders results
in the limit of large numbers of chiral superfields are necessarily
inconclusive. However, we argue that the general idea of ultraviolet-stable
fixed points in supersymmetric gauge theories is viable, and exhibit models
that can satisfy all known constraints.

</DOC>
<DOC>
<DOCNO> 123120 </DOCNO>
Estimation of Signal and Noise Parameters from CMB Polarization


  We propose a technique for determination of the spectral parameters of the
cosmological signal and pixel noise using observational data on CMB
polarization without any additional assumptions. We introduce the notion of so
called crossing points in the observational maps and derive the theoretical
dependence of the total number of crossing points at different level of the
polarization. Finally, we use the statistics of the signal in the vicinities of
the singular points, where the polarization of the pure CMB vanishes to correct
the final result.

</DOC>
<DOC>
<DOCNO> 10517 </DOCNO>
Characteristic features of anharmonic effects in the lattice dynamics of


  The dispersion in the entire Brillouin zone and the temperature dependence
(right up to the melting temperature) of the anharmonic frequency shift and
phonon damping in a number of fcc metals is investigated on the basis of
microscopic calculations. It is found that the anharmonic effects depend
sharply on the wave vector in the directions $\Gamma$-X, X-W, and $\Gamma$-L
and, in contrast to bcc metals, the magnitude of the effects is not due to the
softness of the initial phonon spectrum. It is shown that the relative
frequency shifts and the phonon damping near melting do not exceed 10-20%. The
relative role of various anharmonic processes is examined, and the relation
between the results obtained and existing experimental data is discussed.

</DOC>
<DOC>
<DOCNO> 117316 </DOCNO>
Twenty-Seven Lines on a Cubic Surface and Heterotic String Spacetimes


  It is hypothetized that the algebra of the configuration of twenty-seven
lines lying on a general cubic surface underlines the dimensional hierarchy of
heterotic string spacetimes.

</DOC>
<DOC>
<DOCNO> 119399 </DOCNO>
Implications of Recent Observational Discoveries for the Nature and


  The discoveries that GRBs have X-ray, optical and radio afterglows have
connected the study of GRBs to the rest of astronomy, and revolutionized the
field. In this review, I discuss the implications that the observation of these
afterglows have for burst energies and luminosities, and for models of the
bursts and their afterglows. I describe recent evidence linking the long,
softer, smoother GRBs detected by BeppoSAX and core collapse supernovae.
Finally, I summarize recent work showing that, if these GRBs are due to the
collapse of massive stars, they may provide a powerful probe of the very high
redshift universe.

</DOC>
<DOC>
<DOCNO> 8592 </DOCNO>
The Field Theory of the q->4+ Potts Model


  The q-state Potts model in two dimensions exhibits a first-order transition
for q>4. As q->4+ the correlation length at this transition diverges. We argue
that this limit defines a massive integrable quantum field theory whose lowest
excitations are kinks connecting 4+1 degenerate ground states. We construct the
S-matrix of this theory and the two-particle form factors, and hence estimate a
number of universal amplitude ratios. These are in very good agreement with the
results of extrapolated series in q^(-1/2) as well as Monte Carlo results for
q=5.

</DOC>
<DOC>
<DOCNO> 121375 </DOCNO>
The Topology of Weak Lensing Fields


  The topology of weak lensing fields is studied using the 2-dimensional genus
statistic. Simulated fields of the weak lensing convergence are used to focus
on the effect of nonlinear gravitional evolution and to model the statistical
errors expected in observational surveys. For large smoothing angles, the
topology is in agreement with the predictions from linear theory. On smoothing
angles smaller than 10', the genus curve shows the non-Gaussian signatures of
gravitational clustering and differs for open and flat cold dark matter models.
Forthcoming surveys with areas larger than 10 square degrees should have
adequate signal-to-noise to measure the non-Gaussian shape and the
$\Omega$-dependence of the genus statistic.

</DOC>
<DOC>
<DOCNO> 14052 </DOCNO>
Optics with an Atom Laser Beam


  We report on the atom optical manipulation of an atom laser beam. Reflection,
focusing and its storage in a resonator are demonstrated. Precise and versatile
mechanical control over an atom laser beam propagating in an inhomogeneous
magnetic field is achieved by optically inducing spin-flips between atomic
ground states with different magnetic moment. The magnetic force acting on the
atoms can thereby be effectively switched on and off. The surface of the atom
optical element is determined by the resonance condition for the spin-flip in
the inhomogeneous magnetic field. A mirror reflectivity of more than 98% is
measured.

</DOC>
<DOC>
<DOCNO> 100627 </DOCNO>
Conformally symmetric circle packings. A generalization of Doyle spirals


  From the geometric study of the elementary cell of hexagonal circle packings
--- a flower of 7 circles --- the class of conformally symmetric circle
packings is defined. Up to Moebius transformations, this class is a three
parameter family, that contains the famous Doyle spirals as a special case. The
solutions are given explicitly. It is shown, that these circle packings can be
viewed as discretizations of the quotient of two Airy functions.
  There is an interactive version of this paper that contains JAVA applets that
let you experiment with the circle packings directly. It is available at
http://www-sfb288.math.tu-berlin.de/Publications/online/

</DOC>
<DOC>
<DOCNO> 70593 </DOCNO>
Dual Unification


  This manuscript has been withdrawn by the author. Some of the material has
been included in the manuscript 'Dualizing the Dual Standard Model'
hep-ph/0102084.

</DOC>
<DOC>
<DOCNO> 100788 </DOCNO>
Correlation functions for symmetrized increasing subsequences


  We show that the correlation functions associated to symmetrized increasing
subsequence problems can be expressed as pfaffians of certain antisymmetric
matrix kernels, thus generalizing the result of math.RT/9907127 for the
unsymmetrized case.

</DOC>
<DOC>
<DOCNO> 119728 </DOCNO>
Structure of the MgII and damped Lyman-alpha systems along the line of


  A study of the absorption systems toward the gravitationally lensed quasar
APM 08279+5255 is presented. Most of the MgII systems in the redshift range
1.2-2.07, although saturated, show large residuals at the bottom of the lines.
The most likely interpretation is that individual clouds within MgII halos do
cover only one of the two brightest QSO images. This reveals that MgII halos
are made of a collection of clouds of radius smaller than about 1 kpc. Two
strong MgII absorbers at z = 1.062 and 1.181 are studied in detail. This is the
first time that the NaI3303 doublet is detected in such high redshift systems.
Together with the detection of the MgI2852 transition, this strongly constrains
the physical characteristics of the gas. The N(NaI)/N(MgI) ratio is found to be
larger than unity, implying that the gas is cool and neutral. The column
densities of NaI, CaII, MgI, TiII, MnII and FeII observed at z = 1.1801 are
very close to that observed along the line of sight towards 23 Ori in our
Galaxy. The shape of the QSO continuum and the relative depletion of Fe, Ti, Mn
and Ca are consistent with the presence of dust at z = 1 (AV = 0.5 mag).
Altogether it is found that the HI column density at z = 1 is of the order of 1
to 5 10**21 cm-2, the corresponding metallicity is in the range 1--0.3 Zsol.
The objects associated with these two systems could both contribute to the lens
together with another possible strong system at z = 1.1727 and the strong
Lyman-alpha system at z = 2.974. The probable damped Ly-alpha system at z =
2.974 has 19.8 < log N(HI) < 20.3. The transverse dimension of the absorber is
larger than 200 pc. Abundances relative to solar are -2.31, -2.26, -2.10, -2.35
and -2.37 for, respectively, Fe, Al, Si, C and O (for log N(HI) = 20.3).
(Abridged)

</DOC>
<DOC>
<DOCNO> 119986 </DOCNO>
Physical parameters and emission mechanism in Gamma-Ray Bursts


  Detailed information on the physical parameters in the sources of
cosmological Gamma-Ray Bursts (GRBs) is obtained from few plausible assumptions
consistent with observations. Model-independent requirements posed by these
assumptions on the emission mechanism in GRBs are formulated. It is found that
the observed radiation in sub-MeV energy range is generated by the synchrotron
emission mechanism, though about ten per cent of the total GRB energy should be
converted via the inverse Compton process into ultra-hard spectral domain
(above 100 GeV). We estimate the magnetic field strength in the emitting
region, the Lorentz factor of accelerated electrons, and the typical energy of
IC photons.
  We show that there is a "line-of-death" relation for GRBs and derive from
this relation the lower limits on both GRB duration and GRB variability
timescale. The upper limit on the Lorentz factor of GRB fireballs is also
found. We demonstrate that steady-state electron distribution consistent with
the Compton losses may produce different spectral indices, e.g., 3/4 as opposed
to the figure 1/2 widely discussed in the literature. It is suggested that the
changes in the decline rate observed in the lightcurves of several GRB
afterglows may be due to the time evolution of spectral break, which appears in
the synchrotron emission generated by steady-state self-consistent electron
distribution.

</DOC>
<DOC>
<DOCNO> 84652 </DOCNO>
An Accelerated Expansion Model in the Absence of the Cosmological


  Based on some observations, the apparent energy, associated with gravity, of
vacuums is defined, with that of normal vacuums to be zero and that of the
vacuums losing some energy to be negative. An important application of the
energy is its contribution to Einstein's equation. A cosmological model,
accounting for recent observations of the accelerated expansion of the
universe, in the absence of the cosmological constant, can be well constructed.
In a certain case, the expansion of the universe would be decelerated at its
early epoch and accelerated at its late epoch. The curvature of the universe
would depend on the ratio of matter energy to total energy. The missing mass
problem does no longer exist in this model. Most negative apparent energy
vacuums might be contained in voids, then the spacetime of galaxy clusters or
that of the solar system would not be significantly affected by this kind of
energy.

</DOC>
<DOC>
<DOCNO> 170653 </DOCNO>
Entangled-State Lithography: Tailoring any Pattern with a Single State


  We demonstrate a systematic approach to Heisenberg-limited lithographic image
formation using four-mode reciprocal binominal states. By controlling the
exposure pattern with a simple bank of birefringent plates, any pixel pattern
on a $(N+1) \times (N+1)$ grid, occupying a square with the side half a
wavelength long, can be generated from a $2 N$-photon state.

</DOC>
<DOC>
<DOCNO> 121784 </DOCNO>
The Unified model and the Seyfert 2 infrared dichotomy


  An optical spectropolarimetric study has shown that the detectability of
polarised broad H-alpha in Seyfert 2 galaxies is correlated to the IRAS f60/f25
flux ratio where only those Seyfert 2s with "warm" IRAS colours show polarised
broad line emission. It was suggested that those Seyfert 2s with "cool" IRAS
colours have highly inclined tori which obscure the broad line scattering
screen.
  I present here hard X-ray observations inconsistent with this picture showing
that the derived column densities of warm and cool Seyfert 2 galaxies are
statistically the same. I classify the Bright Galaxy Sample to produce a
non-Seyfert comparison. The analysis of the properties of these galaxies with
the Seyfert 2s suggest that the IRAS f60/f25 flux ratio is consistent with
implying the relative strength of galactic to Seyfert emission. I show that
this new picture can account for the absence of polarised broad H-alpha in the
cool Seyfert 2s.

</DOC>
<DOC>
<DOCNO> 118511 </DOCNO>
Hard X-ray emission from the galaxy cluster A2256


  After the positive detection by BeppoSAX of hard X-ray radiation up to ~80
keV in the Coma cluster spectrum, we present evidence for nonthermal emission
from A2256 in excess of thermal emission at a 4.6sigma confidence level. In
addition to this power law component, a second nonthermal component already
detected by ASCA could be present in the X-ray spectrum of the cluster, not
surprisingly given the complex radio morphology of the cluster central region.
The spectral index of the hard tail detected by the PDS onboard BeppoSAX is
marginally consistent with that expected by the inverse Compton model. A value
of ~0.05 microG is derived for the intracluster magnetic field of the extended
radio emission in the northern regions of the cluster, while a higher value of
\~0.5 microG could be present in the central radio halo, likely related to the
hard tail detected by ASCA.

</DOC>
<DOC>
<DOCNO> 68008 </DOCNO>
Cosmological perturbation spectra from SL(4,R)-invariant effective


  We investigate four-dimensional cosmological vacuum solutions derived from an
effective action invariant under global SL(n,R) transformations. We find the
general solutions for linear axion field perturbations about homogeneous
dilaton-moduli-vacuum solutions for an SL(4,R)-invariant action and find the
spectrum of super-horizon perturbations resulting from vacuum fluctuations in a
pre big bang scenario. We show that for SL(n,R)-invariant actions with n>3
there exists a regime of parameter space of non-zero measure where all the
axion field spectra have positive spectral tilt, as required if light axion
fields are to provide a seed for anisotropies in the microwave background and
large-scale structure in the universe.

</DOC>
<DOC>
<DOCNO> 67981 </DOCNO>
Reconciling the Two-Loop Diagrammatic and Effective Field Theory


  The mass of the lightest CP-even Higgs boson of the minimal supersymmetric
extension of the Standard Model (MSSM) has previously been computed including
O(alpha alpha_s) two-loop contributions by an on-shell diagrammatic method,
while approximate analytic results have also been obtained via
renormalization-group-improved effective potential and effective field theory
techniques. Initial comparisons of the corresponding two-loop results revealed
an apparent discrepancy between terms that depend logarithmically on the
supersymmetry-breaking scale, and different dependences of the non-logarithmic
terms on the squark mixing parameter, X_t. In this paper, we determine the
origin of these differences as a consequence of different renormalization
schemes in which both calculations are performed. By re-expressing the on-shell
result in terms of MS-bar parameters, the logarithmic two-loop contributions
obtained by the different approaches are shown to coincide. The remaining
difference, arising from genuine non-logarithmic two-loop contributions, is
identified, and its effect on the maximal value of the lightest CP-even Higgs
boson mass is discussed. Finally, we show that in a simple analytic
approximation to the Higgs mass, the leading two-loop radiative corrections can
be absorbed to a large extent into an effective one-loop expression by
evaluating the running top quark mass at appropriately chosen energy scales.

</DOC>
<DOC>
<DOCNO> 118693 </DOCNO>
Is Galactic Structure Compatible with Microlensing Data?


  We generalize to elliptical models the argument of Kuijken (1997), which
connects the microlensing optical depth towards the Galactic bulge to the
Galactic rotation curve. When applied to the latest value from the MACHO
collaboration for the optical depth for microlensing of bulge sources, the
argument implies that the Galactic bar cannot plausibly reconcile the measured
values of the optical depth, the rotation curve and the local mass density.
Either there is a problem with the interpretation of the microlensing data, or
our line of sight to the Galactic centre is highly atypical in that it passes
through a massive structure that wraps only a small distance around the
Galactic centre.

</DOC>
<DOC>
<DOCNO> 84247 </DOCNO>
Some integrals ocurring in a topology change problem


  In a paper presented a few years ago, De Lorenci et al. showed, in the
context of canonical quantum cosmology, a model which allowed space topology
changes (Phys. Rev. D 56, 3329 (1997)). The purpose of this present work is to
go a step further in that model, by performing some calculations only estimated
there for several compact manifolds of constant negative curvature, such as the
Weeks and Thurston spaces and the icosahedral hyperbolic space (Best space).

</DOC>
<DOC>
<DOCNO> 71023 </DOCNO>
Jet rates in the hard scattering process at finite temperature


  We compute the cross-section of the hadronic jets arising from the quark
antiquark pair which are produced from a hard photons (of 4-momentum $q$) in
the plasma, predominantly consisting of thermalised quarks and gluons. The
quark antiquark pair is hard and scattered off the heat bath to form jets,
while the gluons being soft get thermalised in the heat bath. The infrared
divergences cancel in the observable cross-section to $\alpha_s$ order, which
includes the process of emission and absorption of real gluons. Since the
massless quark antiquark pair is hard the Compton scattering processes are
absent in the heat bath and it renders an uncancelled collinear divergent piece
in the cross-section. We regularize it by eliminating the collinear region from
the phase space and write it in terms of jet parameters. The temperature
dependent part of the jet cross-section is regular at large ${\sqrt{q^2}\over
T}$ and vanishes when ${\sqrt{q^2}\over T}\to \infty$. Since jets carry the
thermal signature of the hot plasma the jet production rate can be used as a
thermometer of the heat bath.

</DOC>
<DOC>
<DOCNO> 121486 </DOCNO>
HST/STIS Imaging of the Host Galaxy of GRB980425/SN1998bw


  We present HST/STIS observations of ESO 184-G82, the host galaxy of the
gamma-ray burst GRB 980425 associated with the peculiar Type Ic supernova
SN1998bw. ESO 184-G82 is found to be an actively star forming SBc sub-luminous
galaxy. We detect an object consistent with being a point source within the
astrometric uncertainty of 0.018 arcseconds of the position of the supernova.
The object is located inside a star-forming region and is at least one
magnitude brighter than expected for the supernova based on a simple
radioactive decay model. This implies either a significant flattening of the
light curve or a contribution from an underlying star cluster.

</DOC>
<DOC>
<DOCNO> 119434 </DOCNO>
X-ray Emission of Mkn 421: New Clues From Its Spectral Evolution. I.


  Mkn 421 was repeatedly observed with BeppoSAX in 1997-1998. This is the first
of two papers where we present the results of a thorough temporal and spectral
analysis of all the data available to us, focusing in particular on the flare
of April 1998, which was simultaneously observed also at TeV energies. Here we
focus on the time analysis, while the spectral analysis and physical
interpretation are presented in the companion paper. The detailed study of the
flare in different energy bands reveals very important new results: i) hard
photons lag the soft ones by 2-3 ks -a behavior opposite to what is normally
found in high energy peak BL Lacs X-ray spectra; ii) the flare light curve is
symmetric in the softest X-ray band, while it becomes increasingly asymmetric
at higher energies, with the decay being progressively slower than the rise;
iii) the flux decay of the flare can be intrinsically achromatic if a
stationary underlying emission component is present. The temporal and spectral
information obtained challenge the simplest models currently adopted for the
(synchrotron) emission and most importantly provide clues on the particle
acceleration process.

</DOC>
<DOC>
<DOCNO> 69570 </DOCNO>
Chiral symmetry breaking in the Wegner-Houghton approach


  The Wegner-Houghton formulation of the exact renormalization group evolution
equation is used in order to study the chiral symmetry breaking of the linear
sigma model coupled to an isospin doublet of quarks. A numerical investigation
for a particular truncation of the equation which includes the scalar field
renormalization function is presented.

</DOC>
<DOC>
<DOCNO> 71037 </DOCNO>
Flow equation for Halpern-Huang directions of scalar O(N) models


  A class of asymptotically free scalar theories with O(N) symmetry, defined
via the eigenpotentials of the Gaussian fixed point (Halpern-Huang directions),
are investigated using renormalization group flow equations. Explicit solutions
for the form of the potential in the nonperturbative infrared domain are found
in the large-N limit. In this limit, potentials without symmetry breaking
essentially preserve their shape and undergo a mass renormalization which is
governed only by the renormalization group distance parameter; as a
consequence, these scalar theories do not have a problem of naturalness.
Symmetry-breaking potentials are found to be ``fine-tuned'' in the large-N
limit in the sense that the nontrivial minimum vanishes exactly in the limit of
vanishing infrared cutoff: therefore, the O(N) symmetry is restored in the
quantum theory and the potential becomes flat near the origin.

</DOC>
<DOC>
<DOCNO> 11494 </DOCNO>
Coherent oscillation in a linear quantum system coupled to a thermal


  We consider the time development of the density matrix for a system coupled
to a thermal bath, in models that go beyond the standard two-level systems
through addition of an energy excitation degree of freedom and through the
possibility of the replacement of the spin algebra by a more complex algebra.
We find conditions under which increasing the coupling to the bath above a
certain level decreases the rate of entropy production, and in which the
limiting behavior is a dissipationless sinusoidal oscillation that could be
interpreted as the synchronization of many modes of the uncoupled system.

</DOC>
<DOC>
<DOCNO> 11170 </DOCNO>
Collective excitations of degenerate Fermi gases in anisotropic


  The hydrodynamic low-frequency oscillations of highly degenerate Fermi gases
trapped in anisotropic harmonic potentials are investigated. Despite the lack
of an obvious spatial symmetry the wave-equation turns out to be separable in
elliptical coordinates, similar to a corresponding result established earlier
for Bose-condensates. This result is used to give the analytical solution of
the anisotropic wave equation for the hydrodynamic modes.

</DOC>
<DOC>
<DOCNO> 150415 </DOCNO>
Baby Skyrme models for a class of potentials


  We consider a class of (2+1) dimensional baby Skyrme models with potentials
that have more than one vacum. These potentials are generalisation of old and
new baby Skyrme models;they involve more complicated dependence on phi_3.We
find that when the potential is invariant under phi_3 -> -phi_3 the
configuration corresponding to the baby skyrmions lying "on top of each other"
are the minima of the energy. However when the potential breaks this symmetry
the lowest field configurations correspond to separated baby skyrmions. We
compute the energy distributions for skyrmions of degrees between one and eight
and discuss their geometrical shapes and binding energies. We also compare the
2-skyrmion states for these potentials. Most of our work has been performed
numerically with the model being formulated in terms of three real scalar
fields (satisfying one constraint).

</DOC>
<DOC>
<DOCNO> 40437 </DOCNO>
Production rate of bb(bar) quark pairs from gluons and bb(bar)bb(bar)


  The rates are measured per hadronic Z decay for gluon splitting to bb(bar)
quark pairs, g_bb, and of events containing two bb(bar) quark pairs, g_4b,
using a sample of four-jet events selected from data collected with the OPAL
detector. Events with an enhanced signal of gluon splitting to bb(bar) quarks
are selected if two of the jets are close in phase-space and contain detached
secondary vertices. For the event sample containing two bb(bar) quark pairs,
three of the four jets are required to have a significantly detached secondary
vertex. Information from the event topology is combined in a likelihood fit to
extract the values of g_bb and g_4b, namely g_bb = (3.07 +- 0.53(stat) +-
0.97(syst))x10^-3 g_4b = (0.36 +- 0.17(stat) +- 0.27(syst))x10^-3

</DOC>
<DOC>
<DOCNO> 85009 </DOCNO>
Slow flows of an relativistic perfect fluid in a static gravitational


  Relativistic hydrodynamics of an isentropic fluid in a gravitational field is
considered as the particular example from the family of Lagrangian
hydrodynamic-type systems which possess an infinite set of integrals of motion
due to the symmetry of Lagrangian with respect to relabeling of fluid particle
labels. Flows with fixed topology of the vorticity are investigated in
quasi-static regime, when deviations of the space-time metric and the density
of fluid from the corresponding equilibrium configuration are negligibly small.
On the base of the variational principle for frozen-in vortex lines dynamics,
the equation of motion for a thin relativistic vortex filament is derived in
the local induction approximation.

</DOC>
<DOC>
<DOCNO> 178741 </DOCNO>
A relation among the effective nucleon mass, the incompressibility and


  A relation among the effective nucleon mass $M^*$, the incompressibility $K$
and the effective $\sigma$-meson mass $m_{\rm s}^*$ in nuclear matter is
studied by using the relativistic nuclear model. We found that there is a
strong correlation between $M^*$ and $m_{\rm s}^*$, while there is only a weak
correlation between $K$ and $m_{\rm s}^*$. At the normal density, $m_{\rm s}^*$
is smaller than the one at zero density, if $M^*$ is smaller than 0.8 times of
the nucleon mass at zero density. It is also found that the off-shell effective
mass $\mu_{\rm s}^*$ is related directly to $K$ and $M^*$ at the normal
density.

</DOC>
<DOC>
<DOCNO> 67945 </DOCNO>
Search for Ambient Neutralino Dark Matter at Accelerator


  We investigate the possibility of using accelarator beam particles to collide
with the ambient neutralino dark matter particles in cosmic rays as a way to
search for the cold dark matter. We study in detail its inelastic and elastic
scattering with the projectile particles at electron-positron colliders and
discuss the possible experimental signals and the relevent background.

</DOC>
<DOC>
<DOCNO> 72277 </DOCNO>
Thermalization in a Hartree Ensemble Approximation to Quantum Field


  For homogeneous initial conditions, Hartree (gaussian) dynamical
approximations are known to have problems with thermalization, because of
insufficient scattering. We attempt to improve on this by writing an arbitrary
density matrix as a superposition of gaussian pure states and applying the
Hartree approximation to each member of such an ensemble. Particles can then
scatter via their back-reaction on the typically inhomogeneous mean fields.
Starting from initial states which are far from equilibrium we numerically
compute the time evolution of particle distribution functions and observe that
they indeed display approximate thermalization on intermediate time scales by
approaching a Bose-Einstein form. However, for very large times the
distributions drift towards classical-like equipartition.

</DOC>
<DOC>
<DOCNO> 70740 </DOCNO>
Dual superconductivity, monopole condensation and confining string in


  We show that the QCD vacuum (without dynamical quarks) is a dual
superconductor at least in the low-energy region in the sense that monopole
condensation does really occur. In fact, we derive the dual Ginzburg-Landau
theory (i.e., dual Abelian Higgs model) directly from the SU(2) Yang-Mills
theory by adopting the maximal Abelian gauge. The dual superconductor can be on
the border between type II and type I, excluding the London limit. The masses
of the dual Abelian gauge field is expressed by the Yang-Mills gauge coupling
constant and the mass of the off-diagonal gluon of the original Yang-Mills
theory. Moreover, we can rewrite the Yang-Mills theory into an theory written
in terms of the Abelian magnetic monopole alone at least in the low-energy
region. Magnetic monopole condensation originates in the non-zero mass of
off-diagonal gluons. Finally, we derive the confining string theory describing
the low-energy Gluodynamics. Then the area law of the large Wilson loop is an
immediate consequence of these constructions. Three low-energy effective
theories give the same string tension.

</DOC>
<DOC>
<DOCNO> 85604 </DOCNO>
Realtivity without relativity


  We give a derivation of general relativity and the gauge principle that is
novel in presupposing neither spacetime nor the relativity principle. We
consider a class of actions defined on superspace with two key properties. The
first is 3-coordinate invariance. This is the only postulated symmetry, and it
leads to the standard momentum constraint. The second property is that the
Lagrangian is constructed from a `local' square root of an expression quadratic
in the velocities, `local' because it is taken before integration over 3-space.
It gives rise to quadratic constraints that do not correspond to any symmetry
and are not, in general, propagated by the Euler-Lagrange equations. Therefore
these actions are internally inconsistent. Only one action of this form is well
behaved: the Baierlein-Sharp-Wheeler reparametrisation-invariant action for GR.
  From this viewpoint, spacetime symmetry is emergent. It appears as a `hidden'
symmetry in the (underdetermined) solutions of the evolution equations, without
being manifestly coded into the action itself. In addition, propagation of the
constraints acts as a striking selection mechanism beyond pure gravity. If a
scalar field is included in the configuration space, it must have the same
characteristic speed as gravity. Thus Einstein causality emerges. Finally,
self-consistency requires that any 3-vector field must satisfy Einstein
causality, the equivalence principle and, in addition, the Gauss constraint.
Therefore we recover the standard (massless) Maxwell equations.

</DOC>
<DOC>
<DOCNO> 152448 </DOCNO>
Gauge theories on noncommutative spaces


  I review my results about noncommutative gauge theories and about the
relation of these theories to M(atrix) theory following my lecture on ICMP
2000.

</DOC>
<DOC>
<DOCNO> 68846 </DOCNO>
Extrapolating SU(3) breaking effects from D to B decays


  We consider two SU(3) breaking parameters, $R_1(m_B)$ and $R_2(m_B)$,
appearing in a relation between $B^+\to K\pi$ and $B^+\to\pi\pi$ amplitudes,
which plays an important role in determining the weak phase $\gamma$. We
identify an isospin-related quantity $R_2(m_D)$ measured in $D$ decays,
exhibiting large SU(3) breaking which is likely due to nonfactorizable effects.
With a cautious remark about possible nonfactorizable SU(3) breaking in $B$
decays, we proceed to calculate factorizable SU(3) breaking corrections.
Applying heavy quark symmetry to semileptonic $D$ and B decay form factors, we
find that SU(3) breaking in $R_2(m_B)/R_1(m_B)$ may be significantly larger
than estimated from certain model calculations of form factors.

</DOC>
<DOC>
<DOCNO> 119429 </DOCNO>
A bright X-ray transient towards NGC 5128 (Centaurus A)


  During five ROSAT HRI observations in July 1995, a bright X-ray source
(designated 1RXH J132519.8-430312) was detected 2.5' south-west of the nucleus
of NGC 5128 (Centaurus A) at the outer regions of the elliptical galaxy. At
that time it was the brightest point source in the ROSAT HRI field-of-view. All
other ROSAT observations made before and after these observations show no trace
of the source suggesting that this is a highly variable object. Chandra
observations of Cen A made in September 1999 show a source at the ROSAT
position which may be the quiescent counterpart of the transient. It is very
probable that the transient is located in NGC 5128. Given the existence of a
transient source that close to the direction of NGC 5128, all observations (at
least in soft X-rays) of Cen A, with instruments of low spatial resolution,
must take the presence and variability of this object into account.

</DOC>
<DOC>
<DOCNO> 121057 </DOCNO>
Oxygen Absorption in M87: Evidence for a Warm+Hot ISM


  We present a re-analysis of the ROSAT PSPC data within the central 100 kpc of
M87 to search for intrinsic oxygen absorption similar to that recently measured
in several galaxies and groups. Using a spatial-spectral deprojection analysis
we find the strongest evidence to date for intrinsic oxygen absorption in the
hot gas of a galaxy, group, or cluster. Single-phase plasma models modified by
intervening Galactic absorption cannot fit the 0.2-2.2 keV PSPC data as they
under-predict the 0.2-0.4 keV region and over-predict the 0.5-0.8 keV region
where the emission and absorption residuals are obvious upon visual inspection
of the spectral fits. Since the excess emission between 0.2-0.4 keV rules out
intrinsic absorption from cold gas or dust, the most reasonable model for the
excess emission and absorption features is warm, collisionally ionized gas with
a temperature of ~10^6 K. Simple multiphase models (cooling flow, two phases)
modified by both intervening Galactic absorption and by a single oxygen edge
provide good fits and yield temperatures and Fe abundances of the hot gas that
agree with previous determinations by ASCA and SAX. The multiphase models of
M87 inferred from the PSPC can account for the excess EUV emission observed
with EUVE and the excess X-ray absorption inferred from EINSTEIN and ASCA data
above 0.5 keV. Although the total mass of the warm gas implied by the oxygen
absorption is consistent with the matter deposited by a cooling flow, the
suppression of the mass deposition rate and the distortion of the X-ray
isophotes in the region where the radio emission is most pronounced suggest
some feedback effect from the AGN on the cooling gas. (Abridged)

</DOC>
<DOC>
<DOCNO> 12587 </DOCNO>
Dynamic concentration of motors in microtubule arrays


  We present experimental and theoretical studies of the dynamics of molecular
motors in microtubule arrays and asters. By solving a convection-diffusion
equation we find that the density profile of motors in a two-dimensional aster
is characterized by continuously varying exponents. Simulations are used to
verify the assumptions of the continuum model. We observe the concentration
profiles of kinesin moving in quasi two-dimensional artificial asters by
fluorescent microscopy and compare with our theoretical results.

</DOC>
<DOC>
<DOCNO> 13869 </DOCNO>
Spinor Description of a General Spin-J System


  We consider a spin coherent states description of a general quantum spin
system. It is shown that it is possible to use the spin-1/2 representation to
study the general spin-J case. We identify the 1/2 spinor components as the
homogeneous coordinates of the projective space associated to the complex
variable that labels the coherent states and establish a relation between the
two-component spinor and the bosonic Schwinger representation of a spin
operator. We rewrite the equations of motion, obtained from the path integral
for the evolution operator or partition function, in terms of the 1/2 spinor
and define the effective Hamiltonian of its evolution.

</DOC>
<DOC>
<DOCNO> 118401 </DOCNO>
RXTE observation of NGC 6240: a search for the obscured active nucleus


  The wide-band energy spectrum of NGC6240 over the range 0.5-200keV is
investigated using the RXTE and ASCA data. The RXTE data provide the spectrum
beyond the ASCA range (0.5-10 keV) with significant detection of signals up to
20keV and the upper limits above 20keV. The spectrum above 10keV is found to be
very flat. A strong iron-K emission line discovered in the previous ASCA
observation is also confirmed with the RXTE PCA. These results provide further
evidence for the dominance of a reflection component, i.e. emission from cool
material illuminated by an AGN. By fitting the spectra obtained with RXTE and
ASCA simultaneously, we satisfactorily modeled the AGN spectrum with a Compton
reflection component and probably a transmitted AGN component penetrating
through a thick absorber. The X-ray luminosity of the AGN is estimated to be in
the range 4x10^43 - 6x10^44 ergs/s in the range 2-10keV, which categorizes
NGC6240 among the most luminous Seyfert nuclei. The ratio of the 2-10keV X-ray
luminosity to the infrared luminosity, L_X(2-10keV)/L_IR, is 0.01 - 0.1, which
implies a quite substantial, if not dominant, contribution of AGN to the
infrared luminosity.

</DOC>
<DOC>
<DOCNO> 7945 </DOCNO>
The Physics of the Glass Transition


  In this talk, after a short phenomenological introduction on glasses, I will
describe some recent progresses that have been done in glasses using the
replica method in the definition and in the evaluation of the configurational
entropy (or complexity). These results are at the basis of some analytic
computations of the thermodynamic glass transition and of the properties below
the phase transition point.

</DOC>
<DOC>
<DOCNO> 151423 </DOCNO>
Non-commutative spaces in physics and mathematics


  The present review aims both to offer some motivations and mathematical
prerequisites for a study of NCG from the viewpoint of a theoretical physicist
and to show a few applications to matrix theory and results obtained.
  Lectures given by the author at the TMR School on contemporary string theory
and brane physics, 26 Jan--2 Feb 2000, Torino.

</DOC>
<DOC>
<DOCNO> 69211 </DOCNO>
Scalar Meson Decay Constants and the Nature of the a_0(980)


  The a_0(980), a_0(1450) and K_0(1430) decay constants are determined using a
form of QCD sum rules known to produce a very accurate determination of the rho
decay constant. The ratio of a_0(980) to K_0(1430) decay constants is shown to
be ~0.6, ruling out both the ``loosely-bound-K\bar{K}-molecule'' and Gribov
minion scenarios for the a_0(980). Solutions for the isovector scalar spectral
function obtained in the literature from sum rule analyses employing a more
restrictive single-resonance-plus-continuum form of the input spectral ansatz,
are also investigated. These solutions, which suggest, in contrast to the
present results, negligible coupling of the a_0(980) to the isovector scalar
density are shown to produce a poor quality match between the OPE and hadronic
sides of the sum rules employed here, and hence to be strongly disfavored
relative to the present solution.

</DOC>
<DOC>
<DOCNO> 12324 </DOCNO>
Bandgap recovery and electron doping on cleaved [100] surfaces of


  We present the first experimental view of the global band structure of the
surprising divalent hexaborides. An unexpected and dramatic difference between
the electronic structure observed for a region modified by the surface and that
expected for the bulk highlights the fragility of the X-point band overlap that
is thought to underlie the many novel electronic properties of these materials.

</DOC>
<DOC>
<DOCNO> 13244 </DOCNO>
Level and Eigenfunction Statistics in Billiards with Surface Scattering


  Statistical properties of billiards with diffusive boundary scattering are
investigated by means of the supersymmetric sigma-model in a formulation
appropriate for chaotic ballistic systems. We study level statistics,
parametric level statistics, and properties of electron wavefunctions. In the
universal regime, our results reproduce conclusions of the random matrix
theory, while beyond this regime we obtain a variety of system-specific results
determined by the classical dynamics in the billiard. Most notably, we find
that level correlations do not vanish at arbitrary separation between energy
levels, or if measured at arbitrarily large difference of magnetic fields.
Saturation of the level number variance indicates strong rigidity of the
spectrum. To study spatial correlations of wavefunction amplitudes, we
reanalyze and refine derivation of the ballistic version of the sigma-model.
This allows us to obtain a proper matching of universal short-scale
correlations with system-specific ones.

</DOC>
<DOC>
<DOCNO> 11989 </DOCNO>
Integer Quantum Hall Transition and Random SU(N) Rotation


  We reduce the problem of integer quantum Hall transition to a random rotation
of an N-dimensional vector by an su(N) algebra, where only N specially selected
generators of the algebra are nonzero. The group-theoretical structure revealed
in this way allows us to obtain a new series of conservation laws for the
equation describing the electron density evolution in the lowest Landau level.
The resulting formalism is particularly well suited to numerical simulations,
allowing us to obtain the critical exponent \nu numerically in a very simple
way. We also suggest that if the number of nonzero generators is much less than
N, the same model, in a certain intermediate time interval, describes
percolating properties of a random incompressible steady two-dimensional flow.
In other words, quantum Hall transition in a very smooth random potential
inherits certain properties of percolation.

</DOC>
<DOC>
<DOCNO> 100509 </DOCNO>
Decomposition of the Hochschild Complex of a Scheme in Arbitrary


  The paper has been withdrawn by the author, due a gap in the proof of Theorem
6.1. The gap was discovered by M. Van den Bergh.
  Theorem 6.1 is used to prove the main result of the paper, namely Theorem 0.7
(decomposition in arbitrary characteristic). At this time we do not have an
alternate proof.
  Other results of the paper (Theorems 0.2, 0.3, 0.6 and 3.1) are not effected
by this problem, and they remain valid.

</DOC>
<DOC>
<DOCNO> 80879 </DOCNO>
Numerical Study of dense adjoint 2-color matter


  We study the global symmetries of SU(2) gauge theory with N flavors of
staggered fermions in the presence of a chemical potential. We motivate the
special interest of the case N=1 (staggered) with fermions in the adjoint
representation of the gauge group. We present results from numerical
simulations with both hybrid Monte Carlo and the Two-Step Multi-Bosonic
algorithm.

</DOC>
<DOC>
<DOCNO> 69679 </DOCNO>
Extracting m_s From Flavor Breaking in Hadronic Tau Decays


  New finite energy sum rules (FESR's) for extracting m_s from hadronic tau
decay data are constructed which (1) significantly reduce potential theoretical
uncertainties present in existing sum rule analyses and (2) remove problems
associated with both the poor convergence of the OPE representation of the
longitudinal part of the $us$ vector and axial vector correlators and the large
statistical errors in the $us$ spectral data above the K^* region.

</DOC>
<DOC>
<DOCNO> 151559 </DOCNO>
On generalizations of Verlinde's formula


  It is shown that traces of mapping classes of finite order may be expressed
by Verlinde-like formulae. The 3D topological argument is explained, and the
resulting trace identities for modular matrix elements are presented.

</DOC>
<DOC>
<DOCNO> 83228 </DOCNO>
A method for command identification, using modified collision free


  This paper proposes a method for identification of a user`s fixed string set
(which can be a command/instruction set for a terminal or microprocessor). This
method is fast and has very small memory requirements, compared to a
traditional full string storage and compare method. The user feeds characters
into a microcontroller via a keyboard or another microprocessor sends commands
and the microcontroller hashes the input in order to identify valid commands,
ensuring no collisions between hashed valid strings, while applying further
criteria to narrow collision between random and valid strings. The method
proposed narrows the possibility of the latter kind of collision, achieving
small code and memory-size utilization and very fast execution. Hashing is
achieved using additive & rotating hash functions in an iterative form, which
can be very easily implemented in simple microcontrollers and microprocessors.
Such hash functions are presented and compared according to their efficiency
for a given string/command set, using the program found in the appendix.

</DOC>
<DOC>
<DOCNO> 120569 </DOCNO>
Simulations of Pregalactic Structure Formation with Radiative Feedback


  We present results from three-dimensional hydrodynamic simulations of the
high redshift collapse of pregalactic clouds including feedback effects from a
soft H2 photodissociating UV radiation field. The simulations use an Eulerian
adaptive mesh refinement technique to follow the nonequilibrium chemistry of
nine chemical species with cosmological initial conditions drawn from a popular
Lambda-dominated cold dark matter model. The results confirm that the soft UV
background can delay the cooling and collapse of small halos (~10^6 Msun). For
reasonable values of the photo-dissociating flux, the H2 fraction is in
equilibrium throughout most of the objects we simulate. We determine the mass
threshold for collapse for a range of soft-UV fluxes and also derive a simple
analytic expression. Continuing the simulations beyond the point of initial
collapse demonstrates that the fraction of gas which can cool depends mostly on
the virial mass of the halo and the amount of soft-UV flux, with remarkably
little scatter. We parameterize this relation, for use in semi-analytic models.

</DOC>
<DOC>
<DOCNO> 179050 </DOCNO>
Relativistic NN scattering equations without partial-wave decomposition


  Relativistic quasi-potential equations describing NN scattering are compared.
Within the spectator formalism a cancellation is seen to occur between
retardation and negative-energy effects.

</DOC>
<DOC>
<DOCNO> 13309 </DOCNO>
Evolution of the resonance and incommensurate spin fluctuations in


  Polarized and unpolarized neutron triple-axis spectrometry was used to study
the dynamical magnetic susceptibility $\chi^{\prime\prime}({\bf q},\omega)$ as
a function of energy ($\hbar\omega$) and wave vector (${\bf q}$) in a wide
temperature range for the bilayer superconductor YBa$_2$Cu$_3$O$_{6+x}$ with
oxygen concentrations, $x$, of 0.45, 0.5, 0.6, 0.7, 0.8, 0.93, and 0.95. The
most prominent features in the magnetic spectra include a spin gap in the
superconducting state, a pseudogap in the normal state, the much-discussed
resonance, and incommensurate spin fluctuations below the resonance. We
establish the doping dependence of the spin gap in the superconducting state,
the resonance energy, and the incommensurability of the spin fluctuations. We
discuss in detail the procedure used for separating the magnetic scattering
from phonon and other spurious effects. In the comparison of our experimental
results with various microscopic theoretical models, particular emphasis was
made to address the similarities and differences in the spin fluctuations of
YBa$_2$Cu$_3$O$_{6+x}$ and La$_{2-x}$Sr$_x$CuO$_4$.

</DOC>
<DOC>
<DOCNO> 100804 </DOCNO>
Generalized vertex algebras generated by parafermion-like vertex


  It is proved that for a vector space W, any set of parafermion-like vertex
operators on W in a certain canonical way generates a generalized vertex
algebra in the sense of [DL2] with W as a natural module. This result
generalizes a result of [Li2]. As an application, generalized vertex algebras
are constructed from Lepowsky-Wilson's Z-algebras of any nonzero level.

</DOC>
<DOC>
<DOCNO> 169793 </DOCNO>
Universal construction of unitary transformation of quantum computation


  Any unitary transformation of quantum computational networks is explicitly
decomposed, in an exact and unified form, into a sequence of a limited number
of one-qubit quantum gates and the two-qubit diagonal gates that have diagonal
unitary representation in usual computational basis. This decomposition may be
simplified greatly with the help of the properties of the finite-dimensional
multiple-quantum operator algebra spaces of a quantum system and the specific
properties of a given quantum algorithm. As elementary building blocks of
quantum computation, the two-qubit diagonal gates and one-qubit gates may be
constructed physically with one- and two-body interactions in a two-state
quantum system and hence could be conveniently realized experimentally. The
present work will be helpful for implementing generally any N-qubit quantum
computation in those feasible two-state quantum systems and determining
conveniently the time evolution of these systems in course of quantum
computation.

</DOC>
<DOC>
<DOCNO> 170030 </DOCNO>
Optimal local implementation of non-local quantum gates


  We investigate the minimal resources that are required in the local
implementation of non-local quantum gates in a distributed quantum computer.
Both classical communication requirements and entanglement consumption are
investigated. We present general statements on the minimal resource
requirements and present optimal procedures for a number of important gates,
including CNOT and Toffoli gates. We show that one bit of classical
communication in each direction is both necessary and sufficient for the
non-local implementation of the quantum CNOT, while in general two bits in each
direction is required for the implementation of a general two bit quantum gate.
In particular, the state-swapper requires this maximum classical communication
overhead. Extensions of these ideas to multi-party gates are presented.

</DOC>
<DOC>
<DOCNO> 71501 </DOCNO>
QCD radiative corrections to $\gamma^*\gamma^* \to$ hadrons


  We compute the order-$\as$ corrections to the total cross section and to jet
rates for the process $\epem\to\epem +$ hadrons, where the hadrons are produced
through crossed-channel quark exchange in the hard scattering of two off-shell
photons originating from the incoming leptons. We use a next-to-leading order
general-purpose partonic Monte Carlo event generator that allows the
computation of a rate differential in the produced leptons and hadrons. We
compare our results with the available experimental data for $\epem\to\epem +$
hadrons at LEP2.

</DOC>
<DOC>
<DOCNO> 121948 </DOCNO>
The Optical Gravitational Lensing Experiment. Ages of about 600 Star


  We present results of age determination based on the standard procedure of
isochrone fitting for about 600 star clusters younger than about 1.2 Gyr from
the central parts of the LMC. Comparison of age distributions of star clusters
from the LMC and the SMC shows that cluster formation histories are different
in these galaxies. The age distribution of the LMC clusters reveals bursty
nature of cluster formation in this galaxy, with contrast to the relatively
uniform distribution of cluster ages in the SMC. We detected three extended
peaks in the distribution of ages of LMC clusters, located at about 7 Myr, 125
Myr and 0.8 Gyr. All detected peaks have complex structure. While the structure
of the youngest and the oldest peaks may be spurious due to accuracy of age
determination, in the middle peak two evident sub-peaks at 100 Myr and 160 Myr
are clearly seen. Similar peaks are seen in the distribution of ages of
clusters from the SMC, which indicates that increased cluster formation ratio
during these periods might be caused by the last encounter between the
Magellanic Clouds. The sample of clusters from the LMC is overabundant in very
young (<10 Myr) and old (>400 Myr) clusters, and underabundant in clusters
having ages in the range from 80 to 15 Myr with respect to the studied sample
of clusters from the SMC.

</DOC>
<DOC>
<DOCNO> 85078 </DOCNO>
Quasi-spherical approximation for rotating black holes


  We numerically implement a quasi-spherical approximation scheme for computing
gravitational waveforms for coalescing black holes, testing it against angular
momentum by applying it to Kerr black holes. As error measures, we take the
conformal strain and specific energy due to spurious gravitational radiation.
The strain is found to be monotonic rather than wavelike. The specific energy
is found to be at least an order of magnitude smaller than the 1% level
expected from typical black-hole collisions, for angular momentum up to at
least 70% of the maximum, for an initial surface as close as $r=3m$.

</DOC>
<DOC>
<DOCNO> 151265 </DOCNO>
Chiral Charged Fermions, One Dimensional Quantum Field Theory and Vertex


  We give an explicit $L^2$-representation of chiral charged fermions using the
Hardy-Lebesgue octant decomposition. In the " pure" case such a representation
was already used by M. Sato in holonomic field theory. We study both "pure" and
" mixed" cases. In the compact case we rigorously define unsmeared chiral
charged fermion operators inside the unit circle. Using chiral fermions we
orient our findings towards a functional analytic study of vertex algebras as
one dimensional quantum field theory.

</DOC>
<DOC>
<DOCNO> 151992 </DOCNO>
The Hagedorn transition in non-commutative open string theory


  The Hagedorn transition in non-commutative open string theory (NCOS) is
relatively simple because gravity decouples. For NCOS theories in no more than
five spacetime dimensions, the Hagedorn transition is second order, and the
high temperature phase involves long, nearly straight fundamental strings
separating from the D-brane on which the NCOS theory is defined. Above five
spacetime dimensions interaction effects become important below the Hagedorn
temperature. Although this complicates studies of the transition, we believe
that the high temperature phase again involves long strings liberated from the
bound state.

</DOC>
<DOC>
<DOCNO> 117304 </DOCNO>
An improved empirical equation for bunch lengthening in electron storage


  In this paper we propose an improved empirical equation for the bunch
lengthening in electron storage rings. The comparisons are made between the
analytical and experimental results, and the agreements are quite well. This
improved equation can be equally applied to the case where a storage ring is
very resistive (such as the improved SLC damping rings) instead of inductive as
usual.

</DOC>
<DOC>
<DOCNO> 119363 </DOCNO>
On the intensity of the cosmic X-ray background


  Measurements of the intensity of the cosmic X-ray background (XRB) carried
out over small solid angles are subject to spatial variations due to the
discrete nature of the XRB. This cosmic variance can account for the dispersion
of XRB intensity values found within the ASCA, BeppoSAX and ROSAT missions
separately. However there are differences among the values obtained in the
different missions which are not due to spatial fluctuations but, more likely,
to systematic cross-calibration errors. Prompted by recent work which shows
that ROSAT PSPC has calibration differences with all the other missions, we
compute a bayesian estimate for the XRB intensity at 1 keV of
10.0^{+0.6}_{-0.9} keV/cm2/s/keV/sr (90 per cent confidence errors) using the
ASCA and BeppoSAX data points. However, this value is still significantly
larger than the HEAO-1 intensity measured over many thousands of square degrees
(8 keV/cm2/s/keV/sr).

</DOC>
<DOC>
<DOCNO> 178806 </DOCNO>
Local energy-density functional approach to many-body nuclear systems


  The ground-state properties of superfluid nuclear systems with ^1S_0 pairing
are studied within a local energy-density functional (LEDF) approach. A new
form of the LEDF is proposed with a volume part which fits the Friedman-
Pandharipande and Wiringa-Fiks-Fabrocini equation of state at low and moderate
densities and allows an extrapolation to higher densities preserving causality.
For inhomogeneous systems, a surface term with two free parameters is added. In
addition to the Coulomb direct and exchange interaction energy, an effective
density-dependent Coulomb-nuclear correlation term is included with one more
free parameter, giving a contribution of the same order of magnitude as the
Nolen-Schiffer anomaly in Coulomb displacement energy. The root-mean-square
deviations from experimental masses and radii with the proposed LEDF come out
about a factor of two smaller than those obtained with the conventional
functionals based on the Skyrme or finite-range Gogny force, or on the
relativistic mean-field theory. The generalized variational principle is
formulated leading to the self-consistent Gor'kov equations which are solved
exactly, with physical boundary conditions both for the bound and scattering
states. With a zero-range density-dependent cutoff pairing interaction
incorporating a density-gradient term, the evolution of differential
observables such as odd-even mass differences and staggering in charge radii,
is reproduced reasonably well, including kinks at magic neutron numbers. An
extrapolation to infinite nuclear matter is discussed. We study also the dilute
limit in both the weak and strong coupling regime.

</DOC>
<DOC>
<DOCNO> 100096 </DOCNO>
S\'eries Gevrey de type arithm\'etique, II. Transcendance sans


  In this second part, we study the Diophantine properties of values of
arithmetic Gevrey series of non-zero order at algebraic points. We rely on the
fact, proved in the first part, that the minimal differential operator (with
polynomial coefficients) which annihilates such a series has no non-trivial
singularity outside the origin and infinity.
  We show how to draw from this fact some transcendence properties, and
recover in particular the fundamental theorem of the Siegel-Shidlovsky theory
on algebraic independence of values of E-functions. The paradox of the title
points out the contrast between the qualitative aspect of this new argument
and the essentially quantitative aspect of the traditional approach.
  At last, we discuss q-analogues of the theory (theta-functions,
q-exponential,...).

</DOC>
<DOC>
<DOCNO> 11633 </DOCNO>
Scaling behaviour in the fracture of fibrous materials


  We study the existence of distinct failure regimes in a model for fracture in
fibrous materials. We simulate a bundle of parallel fibers under uniaxial
static load and observe two different failure regimes: a catastrophic and a
slowly shredding. In the catastrophic regime the initial deformation produces a
crack which percolates through the bundle. In the slowly shredding regime the
initial deformations will produce small cracks which gradually weaken the
bundle. The boundary between the catastrophic and the shredding regimes is
studied by means of percolation theory and of finite-size scaling theory. In
this boundary, the percolation density $\rho$ scales with the system size $L$,
which implies the existence of a second-order phase transition with the same
critical exponents as those of usual percolation.

</DOC>
<DOC>
<DOCNO> 8688 </DOCNO>
Instabilities of vortices in a binary mixture of trapped Bose-Einstein


  Correspondence between frequency and energy spectra and biorthogonality
conditions for the excitations of Bose-Einstein condensates described by
Gross-Pitaevskii model have been derived selfconsistently revealing several
novel aspects originating in nonselfadjoitness of the Bogoliubov operator. It
has been demonstrated that frequency resonances of the excitations with
positive and negative energies can lead to their mutual annihilation and
appearance of the collective modes with complex frequencies and zero energies.
Conditions for the avoided crossing of energy levels have also been discussed.
General theory has been verified both numerically and analytically in the weak
interaction limit considering an example of vortices in a binary mixture of
condensates. Growth of excitations with complex frequencies leads to spiraling
of the unit and double vortices out of the condensate center to its periphery
and to splitting of the double and higher order vortices to the unit ones.

</DOC>
<DOC>
<DOCNO> 118882 </DOCNO>
Characterizing the Low-Frequency QPO behavior of the X-ray Nova XTE


  For all 209 RXTE observations of the 7-Crab X-ray nova XTE J1550-564, we
analyzed the X-ray power spectra, phase lags, and coherence functions. These
observations cover the entire 250 day outburst cycle of the source and are the
most complete and arguably the richest data set for any black hole X-ray nova.
We find that there are three fundamental types of QPO behavior--one more than
reported by Wijnands, Homan, & van der Klis (1999, ApJ, 526, 33). The new type
occurred during the first half of the outburst. These three types of QPO
behavior can be grouped according to the relative contributions of the disk and
power-law components to the total flux.

</DOC>
<DOC>
<DOCNO> 7749 </DOCNO>
Josephson plasma resonance in k-(BEDT-TTF)2Cu(NCS)2


  A cavity perturbation technique is used to study the microwave response of
the organic superconductor k-(BEDT-TTF)2Cu(NCS)2. Observation of a Josephson
plasma resonance, below Tc (approx. 10 K), enables investigation of the vortex
structure within the mixed state of this highly anisotropic, type-II,
superconductor. Contrary to previous assumptions, frequency dependent studies
(28 - 153 GHz) indicate that the squared plasma frequency depends exponentially
on the magnetic field strength. Such behavior has been predicted for a weakly
pinned quasi-two-dimensional vortex lattice [Bulaevskii et al. Phys. Rev. Lett.
74, 801 (1995)], but has not so far been observed experimentally. Our data also
suggests a transition in the vortex structure near the irreversibility line not
previously reported for an organic superconductor using this technique.

</DOC>
<DOC>
<DOCNO> 12848 </DOCNO>
Two-species branching annihilating random walks with one offspring


  We study the effects of hard core (HC) interactions between different species
of particles on two-species branching annihilating random walks with one
offspring(BAW$_2$(1)). The single-species model belongs to the directed
percolation (DP) universality class. In the BAW$_2$(1) model, a particle
creates one particle of the same species in its neighborhood with the
probability $\sigma (1-p)$ and of the different species with $(1-\sigma)(1-p)$,
where $p$ is the hopping probability. Without HC interactions, this model
always exhibits the DP-type absorbing transition for all $\sigma$. Even with HC
interactions, the nature of the phase transitions does not change except near
$\sigma=0$, where the HC interaction destabilizes and completely wipes away the
absorbing phase. The model is always active except at the annihilation fixed
point of zero branching rate ($p=1$). Critical behavior near the annihilation
fixed point is characterized by exponents $\beta = \nu_\perp =1/2$ and
$\nu_{||} = 1$.

</DOC>
<DOC>
<DOCNO> 120938 </DOCNO>
Infrared L Band Observations of the Trapezium Cluster: A Census of


  We report the results of a sensitive near-infrared JHKL imaging survey of the
Trapezium cluster in Orion. We use the JHKL colors to obtain a census of
infrared excess stars in the cluster. Of (391) stars brighter than 12th
magnitude in the K and L bands, 80 +/- 7% are found to exhibit detectable
infrared excess on the J-H, K-L color-color diagram. Examination of a subsample
of 285 of these stars with published spectral types yields a slightly higher
infrared excess fraction of 85%. We find that 97% of the optical proplyds in
the cluster exhibit excess in the JHKL color-color diagram indicating that the
most likely origin of the observed infrared excesses is from circumstellar
disks. We interpret these results to indicate that the fraction of stars in the
cluster with circumstellar disks is between 80-85%. Moreover, we find that the
probability of finding an infrared excess/protoplanetary disk around a star is
independent of stellar mass over essentially the entire range of the stellar
mass function down to the hydrogen burning limit. We identify 78 stars in our
sample characterized by K-L colors suggestive of deeply embedded protostellar
objects. If even a modest fraction fraction (i.e., ~ 50%) of these objects are
protostars, then star formation could be continuing in the molecular ridge at a
rate comparable to that which produced the foreground Trapezium cluster.

</DOC>
<DOC>
<DOCNO> 102221 </DOCNO>
A proof of Pisot's dth root conjecture


  Let $\{b(n):n\in\N\}$ be the sequence of coefficients in the Taylor expansion
of a rational function $R(X)\in\Q(X)$ and suppose that b(n) is a perfect
$d^{\rm th}$ power for all large n. A conjecture of Pisot states that one can
choose a $d^{\rm th}$ root a(n) of b(n) such that $\sum a(n)X^n$ is also a
rational function. Actually, this is the fundamental case of an analogous
statement formulated for fields more general than $\Q$. A number of papers have
been devoted to various special cases. In this note we shall completely settle
the general case.

</DOC>
<DOC>
<DOCNO> 151448 </DOCNO>
Orientifold Planes, Type I Wilson Lines and Non-BPS D-branes


  There is a longstanding puzzle concerned with the existence of Op~-planes
with p>=6, which are orientifold p-planes of negative charge with stuck
Dp-branes. We study the consistency of configurations with various orientifold
planes and propose a resolution to this puzzle. It is argued that O6~-planes
are possible in massive IIA theory with odd cosmological constant, while
O7~-planes and O8~-planes are not allowed. Various relations between
orientifold planes and non-BPS D-branes are also addressed.

</DOC>
<DOC>
<DOCNO> 68127 </DOCNO>
Covariant Description of Composite Meson Systems and Chiral Symmetry


  Assuming the spin-independence for confining force, we give a covariant quark
representation of general composite meson systems with definite Lorentz
transformation properties. For benefit of this representation we are able to
deduce automatically the transformation rules of composite mesons for general
symmetry operations from those of constituent (exciton) quarks. Applying this
we investigate especially physical implication of chiral symmetry for the meson
systems, and point out a possibility of existence of new meson multiplets.

</DOC>
<DOC>
<DOCNO> 10206 </DOCNO>
Properties of strongly correlated two-dimensional electron gas in


  We discuss properties of strongly correlated two-dimensional electron gas in
semiconductor layers at low electron concentrations assuming that the electron
liquid is close to crystalization. Analogy with the theory of 3He is
emphasized.

</DOC>
<DOC>
<DOCNO> 151526 </DOCNO>
A supersymmetric Type IIB Randall-Sundrum realization


  We show that an earlier domain wall solution of type IIB supergravity
provides a supersymmetric realization of the Randall-Sundrum brane-world, and
give its ten-dimensional interpretation in terms of IIB 3-branes. We also
explain how previous no-go theorems are circumvented. In particular, whereas
D=5 supergravity scalars have AdS_5 energy E_0 <= 4 and are unable to support a
D=5 positive tension brane, our scalar has E_0=8, and is the breathing mode of
the S^5 compactification. Another essential element of the construction is the
implementation of a Z_2 symmetry by patching together compactifications with
opposite signs for their 5-form field strengths. This is thus a IIB analogue of
a previous D=5 3-brane realization of the Horava-Witten orbifold. A
mode-locking phenomenon avoids the appearance of negative energy zero-modes in
spite of the necessity of a D=10 negative tension brane-source.

</DOC>
<DOC>
<DOCNO> 84137 </DOCNO>
Exact Solution for the Exterior Field of a Rotating Neutron Star


  A four-parameter class of exact asymptotically flat solutions of the
Einstein-Maxwell equations involving only rational functions is presented. It
is able to describe the exterior field of a slowly or rapidly rotating neutron
star with poloidal magnetic field.

</DOC>
<DOC>
<DOCNO> 101860 </DOCNO>
The geometry of three-forms in six and seven dimensions


  We study the special algebraic properties of alternating 3-forms in 6 and 7
dimensions and introduce a diffeomorphism-invariant functional on the space of
differential 3-forms on a closed manifold M in these dimensions. Restricting
the functional to closed forms in a fixed cohomology class, we find that a
critical point which is generic in a suitable sense defines in the
6-dimensional case a complex threefold with trivial canonical bundle and in 7
dimensions a Riemannian manifold with holonomy G2. This approach gives a direct
method of finding a local moduli space, with its special geometry, for these
structures.

</DOC>
<DOC>
<DOCNO> 150985 </DOCNO>
BPS Supermultiplets in Five Dimensions


  BPS representations of 5-dimensional supersymmetry algebras are classified.
For BPS states preserving 1/2 the supersymmetry, there are two distinct classes
of multiplets for N=4 supersymmetry and three classes for N=8 supersymmetry.
For N=4 matter theories, the two 1/2 supersymmetric BPS multiplets are the
massive vector multiplet and the massive self-dual 2-form multiplet. Some
applications to super-Yang-Mills, supergravity and little string theories are
considered.

</DOC>
<DOC>
<DOCNO> 69981 </DOCNO>
B and B_s decays into three pseudoscalar mesons and the determination of


  We reconsider two classical proposals for the determination of the angle
gamma of the unitarity triangle: B^\pm => chi_{c0} \pi^\pm => \pi^+\pi^-\pi^\pm
and B_s => rho^0 K_S => \pi^+ \pi^- K_S. We point out the relevance, in both
cases, of non resonant amplitudes, where the \pi^+ \pi^- pair is produced by
weak decay of a B^* (J^P=1^-) or B_0 (J^P=0^+) off-shell meson. In particular,
for the B decay channel, the inclusion of the B_0 pole completes some previous
analyses and confirms their conclusions, provided a suitable cut in the Dalitz
plot is performed; for the B_s decay the inclusion of the B^*, B_0 amplitudes
enhances the role of the tree diagrams as compared to penguin amplitudes, which
makes the theoretical uncertainty related to the B_s => rho^0 K_S decay process
less significant. While the first method is affected by theoretical
uncertainties, the second one is cleaner, but its usefulness will depend on the
available number of events to perform the analysis.

</DOC>
<DOC>
<DOCNO> 69583 </DOCNO>
The Nucleon Anapole Form Factor in Chiral Perturbation Theory to


  The anapole form factor of the nucleon is calculated in chiral perturbation
theory to sub-leading order. This is the lowest order in which the isovector
anapole form factor does not vanish. The anapole moment depends on counterterms
that reflect short-range dynamics, but the momentum dependence or the form
factor is determined by pion loops in terms of parameters that could in
principle be fixed from other processes. If these parameters are assumed to
have natural size, the sub-leading corrections do not exceed ~ 30% at momentum
Q ~ 300 MeV.

</DOC>
<DOC>
<DOCNO> 85637 </DOCNO>
Bekenstein bounds in de Sitter and flat space


  The D-bound on the entropy of matter systems in de Sitter space is shown to
be closely related to the Bekenstein bound, which applies in a flat background.
This holds in arbitrary dimensions if the Bekenstein bound is calibrated by a
classical Geroch process. We discuss the relation of these bounds to the more
general bound on the entropy to area ratio. We find that black holes do not
saturate the Bekenstein bound in dimensions greater than four.

</DOC>
<DOC>
<DOCNO> 102817 </DOCNO>
Twisted Yangians and folded W-algebras


  We show that the truncation of twisted Yangians are isomorphic to finite
W-algebras based on orthogonal or symplectic algebras. This isomorphism allows
us to classify all the finite dimensional irreducible representations of the
quoted W-algebras. We also give an R-matrix for these W-algebras, and determine
their center.

</DOC>
<DOC>
<DOCNO> 69373 </DOCNO>
EDM operator free from Schiff's theorem


  We present generalized Schiff's transformation on electric dipole moments
(EDM) in quantum field theory. By the unitary transformation, the time and
parity violating interaction $i{ge\over 2} \bar \psi \sigma_{\mu \nu} \gamma_5
\psi F^{\mu \nu}$ is transformed into a new form, but its nonrelativistic
reduction has a unique form, which is free from Schiff's theorem. The
relativistic corrections to the new EDM operator turn out to be a small
increase to the EDM as given by $b_2 (\alpha Z)^2$ with $b_2 \simeq 2 $.
Therefore, the calculation of the EDM with nonrelativistic Hartree-Fock wave
functions presents the most conservative but reliable estimation for the
enhancement factor of the EDM in atoms.

</DOC>
<DOC>
<DOCNO> 14047 </DOCNO>
Director configurations of a nematic liquid crystal confined in a


  Various director configurations of a nematic liquid crystal, confined in a
toroidal volume and subject to an external magnetic field, were evaluated
numerically by performing finite element calculations in three dimensions. The
equilibrium director field is found from a minimization of the elasto-magnetic
energy of the nematic. The director at the inner surface of the torus is fixed,
either along homeotropic or tangential direction. We consider both a
homogeneous and an azimuthal magnetic field, with its direction being in
conflict with the respective surface anchoring.
  The relative stability of topologically inequivalent configurations is
investigated in dependence on the strength of the magnetic field and the
geometrical parameters of the confining torus. We find that in a toroidal
geometry the director "escape" from a disclination, which usually occurs in a
cylindrical tube, is absolutely stable only for weak magnetic fields and
tangential anchoring, whereas for homeotropic anchoring director fields
containing disclination rings are more favorable. When a strong homogeneous
magnetic field is exerted laterally, the resulting director field is not any
more axially symmetric, instead, it reveals curved disclinations of finite
length.

</DOC>
<DOC>
<DOCNO> 100058 </DOCNO>
Eclatement de r\'eseaux de quadriques et bord des instantons de degr\'e


  In their article [1], L. Gruson and M. Skiti have constructed a birationnal
map from the variety $\I$ of mathematical instantons of degree 3 to the variety
of nets of quadrics in $\pd$. They describe by this way two irreducible
componants of the boundary of $\I$ associated to the divisor of nets which
contain a two-plane degenerated quadric and the divisor of L\" uroth nets. In
this article we describe an irreducible componante of the boundary of $\I$ as
the exceptionnal divisor of the blowing-up of the closed set of nets of
quadrics of rank 3.

</DOC>
<DOC>
<DOCNO> 13640 </DOCNO>
Manipulating the Speed of Sound in a Two-Component Bose-Einstein


  We consider a two-component weakly interacting Bose-Einstein condensate in
the presence of an external field which couples the two components. We express
the Hamiltonian in terms of the energy eigenstates of the single-body part of
the Hamiltonian. These eigenstates are the atomic dressed states of quantum
optics. When the energy difference between the two dressed states is much
larger than the mean-field interactions, two-body interactions in the dressed
state basis that do not conserve the number of atoms in each of the two dressed
states are highly suppressed. The two-body interactions then take on a
simplified form in the dressed basis with effective coupling constants that
depend on the intensity and frequency of the external field. This implies that
the chemical potential as well as the quasiparticle spectrum may be controlled
experimentally in a simple manner. We demonstrate this by showing that one may
achieve significant variations in the speed of sound in the condensate, a
quantity which has been measured experimentally.

</DOC>
<DOC>
<DOCNO> 71327 </DOCNO>
Semi-inclusive polarized DIS in terms of Melin moments.I. Light sea


  In connection with the semi-inclusive polarized DIS, it is proposed to
consider the first Melin moments $\Delta q$ of the polarized quark and
antiquark densities, instead of the respective variables $\delta q(x)$, local
in Bjorken x themselves. This gives rise to a very essential simplification of
the next to leading order (NLO) QCD and, besides, allows one to use the
respective QCD sum rules. An expression for $\Delta\bar{u}-\Delta\bar{d}$ in
NLO is obtained which is just a simple combination of the directly measured
asymmetries and of the quantities taken from the unpolarized data.

</DOC>
<DOC>
<DOCNO> 117007 </DOCNO>
High Power Model Fabrication of Biperiodic L-Support Disk-and-Washer


  The high power test model of biperiodic L-support disk-and- washer was
fabricated. Among some trouble in the fabrication, the main one was a vacuum
leak in a brazing process. The repair test of the leak showed a good result;
four units were recovered out of five leak units (recover rate 80%). While an
accelerating mode frequency was tuned at an operating frequency of 2857 MHz by
squeezing method, a coupling mode frequency of 2847MHz and the 3.4% field
flatness (peak to peak ratio) were achieved.

</DOC>
<DOC>
<DOCNO> 13194 </DOCNO>
Numerical model for granular compaction under vertical tapping


  A simple numerical model is used to simulate the effect of vertical taps on a
packing of monodisperse hard spheres. Our results are in agreement with an
experimantal work done in Chicago and with other previous models, especially
concerning the dynamics of the compaction, the influence of the excitation
strength on the compaction efficiency, and some ageing effects. The principal
asset of the model is that it allows a local analysis of the packings. Vertical
and transverse density profiles are used as well as size and volume
distributions of the pores. An interesting result concerns the appearance of a
vertical gradient in the density profiles during compaction. Furthermore, the
volume distribution of the pores suggests that the smallest pores, ranging in
size between a tetrahedral and an octahedral site, are not strongly affected by
the tapping process, in contrast to the largest pores which are more sensitive
to the compaction of the packing.

</DOC>
<DOC>
<DOCNO> 118452 </DOCNO>
Models for the Magnitude-Distribution of Brightest Cluster Galaxies


  The brightest, or first-ranked, galaxies (BCGs) in rich clusters show a very
small dispersion in luminosity, making them excellent standard candles. This
small dispersion has raised questions about the nature of BCGs. Are they simply
the extremes of normal galaxies formed via a stochastic process, or do they
belong to a special class of atypical objects? Arguments have been proposed on
both sides of the debate. Bhavsar (1989) suggested that the distribution in
magnitudes can only be explained by a two-population model. Thus, a new
controversy has arisen. Do first-ranked galaxies consist of one or two
populations of objects? We examine an older and newer data set and present our
results. Two-population models do better than do one-population models. A
simple model where a random boost in the magnitude of a fraction of bright
normal galaxies forms a class of atypical galaxies best describes the observed
distribution of BCG magnitudes. Moreover, the parameters that describe the
model and the parameters of the boost have a strong physical basis.

</DOC>
<DOC>
<DOCNO> 12374 </DOCNO>
Instability in a Two-Dimensional Dilute Interacting Bose System


  The formalism of Ursell operators provides a self-consistent integral
equation for the one-particle reduced operator. In three dimensions this
technique yields values of the shift in the Bose-Einstein condensation (BEC)
transition temperature, as a function of the scattering length, that are in
good agreement with those of Green's function and quantum Monte Carlo methods.
We have applied the same equations to a uniform two-dimensional system and find
that, as we alter the chemical potential, an instability develops so that the
self-consistent equations no longer have a solution. This instability, which
seems to indicate that interactions restore a transition, occurs at a non-zero
value of an effective chemical potential. The non-linear equations are limited
to temperatures greater than or equal to Tc, so that they do not indicate the
nature of the new stable state, but we speculate concerning whether it is a
Kosterlitz-Thouless state or a ``smeared'' BEC, which might avoid any violation
of the Hohenberg theorem, as described in an accompanying paper.

</DOC>
<DOC>
<DOCNO> 170246 </DOCNO>
Noise-free scattering of the quantized electromagnetic field from a


  We study the scattering of the quantized electromagnetic field from a linear,
dispersive dielectric using the scattering formalism for quantum fields. The
medium is modeled as a collection of harmonic oscillators with a number of
distinct resonance frequencies. This model corresponds to the Sellmeir
expansion, which is widely used to describe experimental data for real
dispersive media. The integral equation for the interpolating field in terms of
the in field is solved and the solution used to find the out field. The
relation between the in and out creation and annihilation operators is found
which allows one to calculate the S-matrix for this system. In this model, we
find that there are absorption bands, but the input-output relations are
completely unitary. No additional quantum noise terms are required.

</DOC>
<DOC>
<DOCNO> 13360 </DOCNO>
Dynamics of electrostatically-driven granular media. Effects of Humidity


  We performed experimental studies of the effect of humidity on the dynamics
of electrostatically-driven granular materials. Both conducting and dielectric
particles undergo a phase transition from an immobile state (granular solid) to
a fluidized state (granular gas) with increasing applied field. Spontaneous
precipitation of solid clusters from the gas phase occurs as the external
driving is decreased. The clustering dynamics in conducting particles is
primarily controlled by screening of the electric field but is aided by
cohesion due to humidity. It is shown that humidity effects dominate the
clustering process with dielectric particles.

</DOC>
<DOC>
<DOCNO> 117303 </DOCNO>
Mach-Zehnder interferometer based all optical flip-flop


  For the first time an all optical flip-flop is demonstrated based on two
coupled Mach-Zehnder interferometers which contain semiconductor optical
amplifiers in their arms. The flip-flop operation is discussed and it is
demonstrated using commercially available fiber pigtailed devices. Being based
on Mach-Zehnder interferometers, the flip-flop has potential for very high
speed operation.

</DOC>
<DOC>
<DOCNO> 122232 </DOCNO>
Cosmic Shear and Clusters of Galaxies


  The first detections of cosmic shear signal reported recently by 4
independent groups cover angular scales between one and 10 arcmin. On those
scales, the cosmic shear is a signature of non-linear perturbations, like
groups and clusters of galaxies. We present the results obtained by our team on
CFHT and on the VLT and discuss its impact for the analysis of cluster
abundances and cosmology

</DOC>
<DOC>
<DOCNO> 99495 </DOCNO>
An adelic causality problem related to abelian L-functions


  I associate to a global field K a Lax-Phillips scattering which has the
property of causality if and only if the Riemann Hypothesis holds for all the
abelian L-functions of K. As a Hilbert space closure problem this provides an
adelic variation on a theme initiated by Nyman and Beurling. The adelic aspects
are related to previous work by Tate, Iwasawa and Connes.

</DOC>
<DOC>
<DOCNO> 174451 </DOCNO>
Effect of nucleon exchange on projectile multifragmentation in the


  Multifragmentation of quasiprojectiles was studied in reactions of 28Si beam
with 112Sn and 124Sn targets at projectile energies 30 and 50 MeV/nucleon. The
quasiprojectile observables were reconstructed using isotopically identified
charged particles with Z_f <= 5 detected at forward angles. The nucleon
exchange between projectile and target was investigated using isospin and
excitation energy of reconstructed quasiprojectile. For events with total
reconstructed charge equal to the charge of the beam (Z_tot = 14) the influence
of beam energy and target isospin on neutron transfer was studied in detail.
Simulations employing subsequently model of deep inelastic transfer,
statistical model of multifragmentation and software replica of FAUST detector
array were carried out. A concept of deep inelastic transfer provides good
description of production of highly excited quasiprojectiles. The isospin and
excitation energy of quasiprojectile were described with good overall
agreement. The fragment multiplicity, charge and isospin were reproduced
satisfactorily. The range of contributing impact parameters was determined
using backtracing procedure.

</DOC>
<DOC>
<DOCNO> 71020 </DOCNO>
Wilsonian Matching of Effective Field Theory with Underlying QCD


  We propose a novel way of matching effective field theory with the underlying
QCD in the sense of a Wilsonian renormalization group equation (RGE). We derive
Wilsonian matching conditions between current correlators obtained by the
operator product expansion in QCD and those by the hidden local symmetry (HLS)
model. This determines without much ambiguity the bare parameters of the HLS at
the cutoff scale in terms of the QCD parameters. Physical quantities for the pi
and rho system are calculated by the Wilsonian RGE's from the bare parameters
in remarkable agreement with the experiment.

</DOC>
<DOC>
<DOCNO> 118825 </DOCNO>
Computer simulations of interferometric imaging with the VLT


  We present computer simulations of interferometric imaging with the VLT
interferometer and the AMBER instrument. These simulations include both the
astrophysical modelling of a stellar object by radiative transfer calculations
and the simulation of light propagation from the object to the detector
(through atmosphere, telescopes, and the AMBER instrument), simulation of
photon noise and detector read-out noise, and finally data processing of the
interferograms. The results show the dependence of the visibility error bars on
the following observational parameters: different seeing during the observation
of object and reference star (Fried parameters r_0,object=2.4m, r_0,ref.=2.5m,
different residual tip-tilt error (delta_tt,object=2% of the Airy disk
diameter, delta_tt,ref.=0.1%), and object brightness (K_object=3.5 mag and 11
mag, K_ref.=3.5 mag). Exemplarily, we focus on stars in late stages of stellar
evolution and study one of its key objects, the dusty supergiant IRC+10420 that
is rapidly evolving on human timescales. We show computer simulations of VLTI
interferometry of IRC+10420 with two ATs (wide-field mode, i.e. without fiber
optics spatial filters) and discuss whether the visibility accuracy is
sufficient to distinguish between different theoretical model predictions.

</DOC>
<DOC>
<DOCNO> 71845 </DOCNO>
Lorentz and CPT Tests in QED


  A theoretical framework extending QED in the context of the standard model is
used to analyze a variety of Lorentz and CPT tests in atomic systems.
Experimental signatures of possible Lorentz and CPT violation in these systems
are investigated, and bounds are discussed.

</DOC>
<DOC>
<DOCNO> 122754 </DOCNO>
Cosmic Shear Analysis in 50 Uncorrelated VLT Fields. Implications for


  We observed with the camera FORS1 on the VLT (UT1, ANTU) 50 randomly selected
fields and analyzed the cosmic shear inside circular apertures with diameter
ranging from 0.5 to 5.0 arc-minutes. The images were obtained in optimal
conditions by using the Service Observing proposed by ESO on the VLT, which
enabled us to get a well-defined and homogeneous set of data. The 50 fields
cover a 0.65 square-degrees area spread over more than 1000 square-degrees
which provides a sample ideal for minimizing the cosmic variance. Using the
same techniques as in Van Waerbeke et al. 2000, we measured the cosmic shear
signal and investigated the systematics of the VLT sample. We find a
significant excess of correlations between galaxy ellipticities on those
angular scales. The amplitude and the shape of the correlation as function of
angular scale are remarkably similar to those reported so far. Using our
combined VLT and CFHT data and adding the results published by other teams we
put the first joint constraints on Omega_0 and sigma_8 using cosmic shear
surveys. From a deduced average of the redshift of the sources the combined
data are consistent with sigma_8\simeq (0.59 \pm 0.03) Omega_0^{-0.47} (for a
CDM power spectrum and $\Gamma=0.21$), in excellent agreement with the
cosmological constraints obtained from the local cluster abundance.

</DOC>
<DOC>
<DOCNO> 11695 </DOCNO>
The one-dimensional XXZ model with long-range interactions


  The one-dimensional XXZ model (s=1/2, N sites) with uniform long-range
interactions among the transverse components of the spins is considered. The
Hamiltonian of the model is explicitly given by
$H=J\sum_{j=1}^{N}(s_{j}^{x}s_{j+1}^{x}+s_{j}^{y}s_{j+1}^{y})
-(I/N)\sum_{j,k=1}^{N}s_{j}^{z}s_{k}^{z}-h\sum_{j=1}^{N}s_{j}^{z},$ where the
$s^{x,y,z}$ are half the Pauli spin matrices. The model is exactly solved by
applying the Jordan-Wigner fermionization, followed by a Gaussian
transformation. In the absence of the long-range interactions (I=0), the model,
which reduces to the isotropic XY model, is known to exhibit a second-order
quantum phase transition driven by the field at zero temperature. It is shown
that in the presence of the long-range interactions (I different from 0) the
nature of the transition is strongly affected. For I>0, which favours the
ordering of the transverse components of the spins, the transition is changed
from second- to first-order, due to the competition between transverse and xy
couplings. On the other hand, for I<0, which induces complete frustration of
the spins, a second-order transition is still present, although the system is
driven out of its usual universality class, and its critical exponents assume
typical mean-field values.

</DOC>
<DOC>
<DOCNO> 100369 </DOCNO>
On the distribution of points of bounded height on equivariant


  We prove asymptotic formulas for the number of rational points of bounded
height on smooth equivariant compactifications of the affine space.
  (Nous \'etablissons un d\'eveloppement asymptotique du nombre de points
rationnels de hauteur born\'ee sur les compactifications \'equivariantes lisses
de l'espace affine.)

</DOC>
<DOC>
<DOCNO> 152115 </DOCNO>
Universal Ratios of the Renormalization Group


  The scaling form of the free--energy near a critical point allows for the
definition of various universal ratios of thermodynamical amplitudes. Together
with the critical exponents they characterize the universality classes and may
be useful experimental quantities. We show how these universal quantities can
be computed for a particular class of universality by using several Quantum
Field Theory methods

</DOC>
<DOC>
<DOCNO> 152001 </DOCNO>
Second Order Perturbations of a Macroscopic String; Covariant Approach


  Using a world-sheet covariant formalism, we derive the equations of motion
for second order perturbations of a generic macroscopic string, thus
generalizing previous results for first order perturbations. We give the
explicit results for the first and second order perturbations of a contracting
near-circular string; these results are relevant for the understanding of the
possible outcome when a cosmic string contracts under its own tension, as
discussed in a series of papers by Vilenkin and Garriga. In particular, second
order perturbations are necessaary for a consistent computation of the energy.
  We also quantize the perturbations and derive the mass-formula up to second
order in perturbations for an observer using world-sheet time $\tau $. The high
frequency modes give the standard Minkowski result while, interestingly enough,
the Hamiltonian turns out to be non-diagonal in oscillators for low-frequency
modes. Using an alternative definition of the vacuum, it is possible to
diagonalize the Hamiltonian, and the standard string mass-spectrum appears for
all frequencies. We finally discuss how our results are also relevant for the
problems concerning string-spreading near a black hole horizon, as originally
discussed by Susskind.

</DOC>
<DOC>
<DOCNO> 69347 </DOCNO>
Connecting Green's Functions in an Arbitrary Pair of Gauges and an


  We establish a finite field-dependent BRS transformation that connects the
Yang-Mills path-integrals with Faddeev-Popov effective actions for an arbitrary
pair of gauges F and F'. We establish a result that relates an arbitrary
Green's function [either a primary one or one that of an operator] in an
arbitrary gauge F' to those in gauge F that are compatible to the ones in gauge
F by its construction [in that the construction preserves expectation values of
gauge-invariant observables]. We establish parallel results also for the planar
gauge-Lorentz gauge connection.

</DOC>
<DOC>
<DOCNO> 85224 </DOCNO>
Introduction to supersymmetric spin networks


  In this paper we give a general introduction to supersymmetric spin networks.
Its construction has a direct interpretation in context of the representation
theory of the superalgebra. In particular we analyze a special kind of spin
networks with superalgebra $Osp(1|2n)$. It turns out that the set of
corresponding spin network states forms an orthogonal basis of the Hilbert
space $\cal L\mit^2(\cal A\mit/\cal G)$, and this argument holds even in the
q-deformed case. The $Osp(n|2)$ spin networks are also discussed briefly. We
expect they could provide useful techniques to quantum supergravity and gauge
field theories from the point of non-perturbative view.

</DOC>
<DOC>
<DOCNO> 150953 </DOCNO>
p-Branes Electric-Magnetic Duality and Stueckelberg/Higgs Mechanism: a


  We study the vacuum functional for a system of p-branes interacting with
Maxwell fields of higher rank. This system represents a generalization of the
usual electrodynamics of point particles, with one essential difference:
namely, that the world-history of a p-brane, due to the spatial extension of
the object, may possess a physical boundary. Thus, the objective of this study
is twofold: first, we wish to exploit the breaking of gauge invariance due to
the presence of a physical boundary, in order to generate mass as an
alternative to the Higgs mechanism; second, we wish to investigate how the new
mechanism of mass generation is affected by the duality transformation between
electric and magnetic branes. The whole analysis is performed by using the
path-integral method, as opposed to the more conventional canonical approach.
The advantage of the path integral formulation is that it enables us to Fourier
transform the field strength directly, rather than the gauge potential. To our
knowledge, this field strength formulation represents a new application of the
path integral method, and leads, in a straightforward way, to the dual
representation of the vacuum functional. We find that the effect of the dual
transformation is essentially that of exchanging the role of the gauge fields
defined respectively on the " bulk'' and "boundary" of the p-brane history.

</DOC>
<DOC>
<DOCNO> 99939 </DOCNO>
On symplectic classification of effective 3-forms and Monge-Ampere


  We complete the list of normal forms for effective 3-forms with constant
coefficients with respect to the natural action of symplectomorphisms in
\mathbb{R}^6. We show that the 3-form which corresponds to the Special
Lagrangian equation is among the new members of the classification. The
symplectic symmetry algebras and their Cartan prolongations for these forms are
computed and a local classification theorem for the corresponding Monge-Ampere
equations is proved.

</DOC>
<DOC>
<DOCNO> 67711 </DOCNO>
Higgs Boson Production at the LHC with Soft Gluon Effects


  We present results of QCD corrections to Higgs boson production at the CERN
Large Hadron Collider. Potentially large logarithmic contributions from
multiple soft-gluon emission are summed up to all order in the strong coupling.
Various kinematical distributions, including the Higgs transverse momentum, are
predicted with O(alpha_s^3) precision. Comparison is made to outputs of the
popular Monte Carlo event generator PYTHIA.

</DOC>
<DOC>
<DOCNO> 117955 </DOCNO>
High-Resolution Near-Infrared Imaging of the Powerful Radio Galaxy 3C


  We have obtained high-resolution K'-band images of the powerful z=1.206 radio
galaxy 3C 324 with the Subaru telescope under seeing conditions of 0.3--0.4
arcsec. We clearly resolved the galaxy and directly compared it to the optical
images obtained with the Hubble Space Telescope. The host galaxy of 3C 324 is
revealed to be a moderately luminous elliptical galaxy with a smooth light
profile. The effective radius of the galaxy, as determined by profile fitting,
is 1.3+-0.1 arcsec (1.2 kpc), which is significantly smaller than the value of
2.2 arcsec, published in Best et al. (1998, MNRAS, 292, 758). The peak of the
K'-band light coincides with the position of the radio core, which implies that
the powerful AGN lies at the nucleus of the host galaxy. The peak also
coincides with the gap in the optical knotty structures which may be a dust
lane hiding the UV-optical emission of the AGN from our line of sight; it is
very likely that we are seeing the obscuring structure almost edge-on. We
clearly detected the `aligned component' in the K'-band image by subtracting a
model elliptical galaxy from the observed image. The red R_F702W-K color of the
outer region of the galaxy avoiding the aligned component indicates that the
near infrared light of the host galaxy is dominated by an old stellar
population.

</DOC>
<DOC>
<DOCNO> 11996 </DOCNO>
Quantum Hall effect at low magnetic fields due to electron-electron


  In a recent preprint cond-mat/9906450 (published in PRL 84, 3141 (2000)) Bodo
Huckestein showed that at real experimental conditions it is not possible to
observe the quantum Hall effect (QHE) at $\omega_{c}\tau <1$ predicted by
Khmelnitskii ($\omega_{c}=eB/m$ is the cyclotron frequency and $\tau $ is the
scattering time). We would like to point out here that in fact the situation is
not so hopeless due to the influence of the electron-electron interaction.

</DOC>
<DOC>
<DOCNO> 121964 </DOCNO>
Kinematics from spectroscopy with a wide slit: detecting black holes in


  We consider long-slit emission-line spectra of galactic nuclei when the slit
is wider than the instrumental PSF, and the target has large velocity
gradients. The finite width of the slit generates complex distributions of
brightness at a given spatial point in the measured spectrum, which can be
misinterpreted as coming from additional physically distinct nuclear
components. We illustrate this phenomenon for the case of a thin disc in
circular motion around a nuclear black hole (BH). We develop a new method for
estimating the mass of the BH that exploits a feature in the spectrum at the
outer edge of the BH's sphere of influence, and therefore gives higher
sensitivity to BH detection than traditional methods. Moreover, with this
method we can determine the black hole mass and the inclination of the
surrounding disc separately, whereas the traditional approach to black-hole
estimation requires two long-slit spectra to be taken. We show that with a
given spectrograph, the detectability of a BH depends on the sense of rotation
of the nuclear disc. We apply our method to estimate the BH mass in M84 from a
publicly available spectrum, and recover a value 4 times lower than that
published previously from the same data.

</DOC>
<DOC>
<DOCNO> 119287 </DOCNO>
The Observed Mass Profiles of Dark Halos and The Formation Epochs of


  We have determined the mass profiles of dark halos in 83 objects observed by
ASCA. The point spread function of X-ray telescope was deconvoled by the
Richardson-Lucy algorithm and the temperature profiles were calculated to
obtain the mass profiles. The derived mass profiles are consistent with the NFW
model in 0.01-1.0 r_virial. We found a good correlation between the scale
radius r_s and the characteristic mass density \delta_c, which indicates the
self-similarity of dark halos. The spectrum index of primordial density
fluctuation, P(k) \propto k^n, was determined from the slope of r_s - delta_c
relation. For M_200=10^12-10^15 M_solar, our analysis gives n=-1.2 +/- 0.3 with
a confidence level of 90%. The mass density of dark halos is a good indicator
of the mean mass density of the universe at the time when the halos were
assembled, z=z_f. Assuming delta_c \propto (1+z_f)^3, we have determined the
epoch when each dark halo was assembled. Our analysis indicates that the field
elliptical galaxies and groups of galaxies formed approximately at 1+z_f ~ 15
and at 1+z_f ~ 7-10 respectively.

</DOC>
<DOC>
<DOCNO> 122644 </DOCNO>
Extracting cosmological information from galaxy spectra and observations


  I review the statistical techniques needed to extract information about
physical parameters of galaxies from their observed spectra. This is important
given the sheer size of the next generation of large galaxy redshift surveys.
Going to the opposite extreme I review what we can learn about the nature of
the primordial density field from observations of high--redshift objects.

</DOC>
<DOC>
<DOCNO> 119942 </DOCNO>
The Fall of the Quasar Population


  We derive quantitative predictions of the optical and X-ray luminosity
functions (LF) for QSs in the redshift range $z<3$. Based on BH paradigm, we
investigate how the accretion is controlled by the surrounding structures, as
these grow hierarchically. We argue that for $z < 3$ efficient black hole
fueling is triggered by the encounters of a gas-rich host with its companions
in a group. The dispersion of the dynamical parameters in the encounters
produces a double power-law LF. Strong luminosity evolution (LE) is produced as
these encounters deplete the gas supply in the host; an additional, milder
density evolution obtains since the interactions become progressively rarer as
the groups grow richer but less dense. From the agreement with the optical and
the X-ray data, we conclude that the evolution of the bright quasars is
articulated in two ways. Earlier than $z~3$ the gas-rich protogalaxies grow by
merging, which also induces parallel growth of central holes accreting at
Eddington rates. In the later era of group assemblage the host encounters with
companions drive onto already existing holes further but meager accretion;
these consume the gas in the hosts, and cause supply-limited emissions which
are intermittent, go progressively sub-Eddington and peter out. Then other
fueling processes come to the foreground; we discuss the faint emissions,
especially noticeable in X-rays, which are expected when hosts in the field
cannibalize satellite galaxies with their meager gas contents.

</DOC>
<DOC>
<DOCNO> 150362 </DOCNO>
A note on Riemann normal coordinates


  The goal of this note is to provide a recursive algorithm that allows one to
calculate the expansion of the metric tensor up to the desired order in Riemann
normal coordinates. We test our expressions up to fourth order and predict
results up to sixth order. For an arbitrary number of symmetric partial
derivatives acting on the components of the metric tensor subtle treatment is
required since the degree of complication increases rapidly.

</DOC>
<DOC>
<DOCNO> 117432 </DOCNO>
Micro & strong lensing with the Square Kilometer Array: The


  We present the results from recent VLA 8.5-GHz and WSRT 1.4 and 4.9-GHz
monitoring campaigns of the CLASS gravitational lens B1600+434 and show how the
observed variations argue strongly in favor of microlensing by MACHOs in the
halo of a dark-matter dominated edge-on disk galaxy at z=0.4. The population of
flat-spectrum radio sources with micro-Jy flux-densities detected with the
Square-Kilometer-Array is expected to have dimensions of micro-arcsec. They
will therefore vary rapidly as a result of Galactic scintillation (diffractive
and refractive). However, when positioned behind distant galaxies they will
also show variations due to microlensing, even more strongly than in the case
of B1600+434. Relativistic or superluminal motion in these background sources
typically leads to temporal variations on time scales of days to weeks.
Scintillation and microlensing can be distinguished, and separated, by their
different characteristic time scales and the frequency dependence of their
modulations. Monitoring studies with Square-Kilometer-Array at GHz frequencies
will thus probe both microscopic and macroscopic properties of dark matter and
its mass-function as a function of redshift, information very hard to obtain by
any other method.

</DOC>
<DOC>
<DOCNO> 151949 </DOCNO>
Matter Fields in Curved Space-Time


  We study the geometry of a two-sheeted space-time within the framework of
non-commutative geometry. As a prelude to the Standard Model in curved
space-time, we present a model of a left- and a right- chiral field living on
the two sheeted-space time and construct the action functionals that describe
their interactions.

</DOC>
<DOC>
<DOCNO> 122295 </DOCNO>
Nuclear spectra of polar-ring galaxies


  We report the results of spectroscopic observations of 8 southern polar-ring
galaxies (PRGs), in the wavelength range 5900-7300 \AA. We fing that 5 out of 8
galaxies contain LINERs or Sy nuclei. Taking into consideration all PRGs with
available spectral data, we estimate that about half of all PRGs and PRG
candidates have either LINER or Seyfert nuclei. The observed widths of the
[NII]6583 line in the nuclei of early-type PRGs follow the linewidth - absolute
luminosity relation for normal E/S0 galaxies. We found that one of the observed
galaxies - ESO 576-G69 - is a new kinematically-confirmed polar-ring galaxy
with a spiral host.

</DOC>
<DOC>
<DOCNO> 9792 </DOCNO>
Ground State and Elementary Excitations of the S=1 Kagome Heisenberg


  Low energy spectrum of the S=1 kagom\'e Heisenberg antiferromagnet (KHAF) is
studied by means of exact diagonalization and the cluster expansion. The
magnitude of the energy gap of the magnetic excitation is consistent with the
recent experimental observation for \mpynn. In contrast to the $S=1/2$ KHAF,
the non-magnetic excitations have finite energy gap comparable to the magnetic
excitation. As a physical picture of the ground state, the hexagon singlet
solid state is proposed and verified by variational analysis.

</DOC>
<DOC>
<DOCNO> 117498 </DOCNO>
Observational Limits on Terrestrial-Sized Inner Planets Around the CM


  A lightcurve of the eclipsing binary CM Draconis has been analyzed for the
presence of transits of planets of size >= 2.5 Earth-radii (Re), with periods
of 60 days or less, and in co-planar orbits around the binary system. About 400
million model lightcurves, representing transits from planets with periods
ranging from 7 to 60 days, have been matched/correlated against these data.
This process we call the "transit detection algorithm" or TDA. The resulting
`transit-statistics' for each planet candidate allow the quantification of
detection probabilities, and of false alarm rates.
  Our current lightcurve of CM Dra has a coverage of 1014 hours with 26,043
individual points, at a photometric precision between 0.2% and 0.7%. Planets
significantly larger then 3Re would constitute a `supra-noise' detection, and
for periods of 60 days or less, they would have been detected with a
probability of 90%. `Subnoise' detections of smaller planets are more
constrained. For example, 2.5 Re planets with 10-day periods or less would have
been detected with an 80% probability. The necessity for predicted observations
is illustrated with the nine top planet candidates that emerged from our TDA
analysis. They are the planet candidates with the highest transit-statistics
from the 1994-1998 observing seasons and, for them, transits for the 1999
observing season were predicted. Of the seven candidates that were then
observationally tested in 1999, all were ruled out except one, which needs
further observational confirmation. We conclude that the photometric transit
method is a viable way to search for relatively small, inner extrasolar planets
with moderate-sized telescopes using CCD photometry with a matching-filter
analysis.

</DOC>
<DOC>
<DOCNO> 69496 </DOCNO>
Radiative mass in QCD at high density


  We show that radiatively generated Majorana mass for antiquarks is same as
the Cooper-pair gap. We then calculate the electromagnetic corrections to mass
of particles in the color-flavor locking phase of QCD at high density. The mass
spectrum forms multiplets under $SU(2)_V\times U(1)_V$. The charged pions and
kaons get the electromagnetic mass which is proportional to the Cooper-pair
gap.

</DOC>
<DOC>
<DOCNO> 117441 </DOCNO>
Magnetic ionization fronts II: Jump conditions for oblique magnetization


  We present the jump conditions for ionization fronts with oblique magnetic
fields. The standard nomenclature of R- and D-type fronts can still be applied,
but in the case of oblique magnetization there are fronts of each type about
each of the fast- and slow-mode speeds. As an ionization front slows, it will
drive first a fast- and then a slow-mode shock into the surrounding medium.
Even for rather weak upstream magnetic fields, the effect of magnetization on
ionization front evolution can be important. [Includes numerical MHD models and
an application to observations of S106.]

</DOC>
<DOC>
<DOCNO> 151224 </DOCNO>
A Self-tuning Exact Solution and the Non-existence of Horizons in 5d


  We present an exact thick domain wall solution with naked sigularities to
five dimensional gravity coupled with a scalar field with exponential
potential. In our solution we found exactly the special coefficient of the
exponent as coming from compactification of string theory with cosmological
constant. We show that this solution is self-tuning when a 3-brane is included.
In searching for solution with horizon we found a similar exact solution with
fine-tuned exponent coefficient with an integration constant. Failed to find a
solution with horizon we prove the non-existence of horizons. These naked
sigularities actually can't be resolved by horizon. We also comment on the
physical relevance of this solution.}

</DOC>
<DOC>
<DOCNO> 117774 </DOCNO>
Gravitational Lensing Effects on High Redshift Type II Supernova Studies


  We derive the expected Type II SN differential number counts, N(m), and
Hubble diagram for SCDM and LCDM cosmological models, taking into account the
effects of gravitational lensing (GL) produced by the intervening cosmological
mass. The mass distribution of dark matter halos (ie the lenses) is obtained by
means of a Monte Carlo method applied to the Press-Schechter mass function. The
halos are assumed to have a NFW density profile, in agreement with recent
simulations of hierarchical cosmological models. Up to z=15, the (SCDM, LCDM)
models predict a total number of (857, 3656) SNII/yr in 100 surveyed 4' times
4' fields of the Next Generation Space Telescope. NGST will be able to reach
the peak of the N(m) curve, located at AB approx 30(31) for SCDM(LCDM) in J and
K wavelength bands and detect (75%, 51%) of the above SN events. This will
allow a detailed study of the early cosmic star formation history, as traced by
SNIIe. N(m) is only very mildly affected by the inclusion of lensing effects.
In addition, GL introduces a moderate uncertainty in the determination of
cosmological parameters from Hubble diagrams, when these are pushed to higher
$z$. For example, for a ``true'' LCDM with (Omega_M= 0.4, Omega_Lambda=0.6),
without proper account of GL, one would instead derive
(Omega_{M}=0.36^{+0.15}_{-0.12}, Omega_{Lambda}=0.60^{+0.12}_{-0.24}). We
briefly compare our results with previous similar work and discuss the
limitations of the model.

</DOC>
<DOC>
<DOCNO> 151514 </DOCNO>
A pedestrian approach to the high energy limits of branes and other


  In this article we study limits of models that contain a dimensionful
parameter such as the mass of the relativistic point-particle. The limits are
analogous to the massless limit of the particle and may be thought of as high
energy limits. We present the ideas and work through several examples in a
(hopefully) pedagogical manner. Along the way we derive several new results.

</DOC>
<DOC>
<DOCNO> 170170 </DOCNO>
Sampling functions for multimode homodyne tomography with a single local


  We derive various sampling functions for multimode homodyne tomography with a
single local oscillator. These functions allow us to sample multimode
s-parametrized quasidistributions, density matrix elements in Fock basis, and
s-ordered moments of arbitrary order directly from the measured quadrature
statistics. The inevitable experimental losses can be compensated by proper
modification of the sampling functions. Results of Monte Carlo simulations for
squeezed three-mode state are reported and the feasibility of reconstruction of
the three-mode Q-function and s-ordered moments from 10^7 sampled data is
demonstrated.

</DOC>
<DOC>
<DOCNO> 118836 </DOCNO>
Cosmic Ray Antiprotons


  Cosmic ray antiprotons have been detected for over 20 years and are now
measured reliably. Standard particle and astrophysics predict a conventional
spectrum and abundance of secondary antiprotons consistent with all current
measurements. These measurements place limits on exotic Galactic antiproton
sources and non-standard antiproton properties. Complications arise,
particularly at low energies, with heliospheric modulation of cosmic ray fluxes
and production of standard secondaries from A > 1 nuclear targets. Future
experiments and theoretical developments are discussed.

</DOC>
<DOC>
<DOCNO> 123171 </DOCNO>
Comparison of the H-alpha circumstellar disks in Be/X-ray binaries and


  We present a comparative study of the circumstellar disks in Be/X-ray
binaries and isolated Be stars based upon the H-alpha emission line. From this
comparison it follows that the overall structure of the disks in the Be/X-ray
binaries is similar to the disks of other Be stars, i.e. they are axisymmetric
and rotationally supported. The factors for the line broadening (rotation and
temperature) in the disks of the Be stars and the Be/X-ray binaries seem to be
identical.
  However, we do detect some intriguing differences between the envelopes. On
average, the circumstellar disks of the Be/X-ray binaries are twice as dense as
the disks of the isolated Be stars. The different distribution of the Be/X-ray
binaries and the Be stars seen in the full width at half maximum (FWHM) versus
peak separation diagram indicates that the disks in Be/X-ray binaries have on
average a smaller size, probably truncated by the compact object.

</DOC>
<DOC>
<DOCNO> 121747 </DOCNO>
Fission barriers of neutron-rich and superheavy nuclei calculated with


  Using the ETFSI (extended Thomas-Fermi plus Strutinsky integral) method, we
have calculated the fission barriers of nearly 2000 exotic nuclei, including
all the neutron-rich nuclei up to A=318 that are expected to be relevant to the
r-process, and all the superheavy nuclei in the vicinity of N=184, with Z<=120.
Our calculations were performed with the Skyrme force SkSC4, which was
determined in the ETFSI-1 mass fit. For proton-deficient nuclei in the region
of N=184 we find the barriers to be much higher than previously believed, which
suggests that the r-process path might continue to mass numbers well beyond
300. For the superheavy nuclei we typically find barrier heights of 6-7 MeV.

</DOC>
<DOC>
<DOCNO> 10095 </DOCNO>
Super-lattice, rhombus, square, and hexagonal standing waves in


  Standing wave patterns that arise on the surface of ferrofluids by (single
frequency) parametric forcing with an ac magnetic field are investigated
experimentally. Depending on the frequency and amplitude of the forcing, the
system exhibits various patterns including a superlattice and subharmonic
rhombuses as well as conventional harmonic hexagons and subharmonic squares.
The superlattice arises in a bicritical situation where harmonic and
subharmonic modes collide. The rhombic pattern arises due to the non-monotonic
dispersion relation of a ferrofluid.

</DOC>
<DOC>
<DOCNO> 116857 </DOCNO>
Fractal Statistics


  We consider the recent description of elementary particles in terms of
Quantum Mechanical Kerr-Newman Black Holes, a description which provides a
rationale for and at the same time reconciles the Bohm-hydrodynamical
formulation on the one hand and the Nelsonian stochastiic formulation on the
other. The Boson-Fermion divide is discussed, and it is pointed out that in
special situations, anomalous statistics, rather than Bose-Einstein or
Fermi-Dirac states, can be encountered.

</DOC>
<DOC>
<DOCNO> 83278 </DOCNO>
Can Prosody Aid the Automatic Classification of Dialog Acts in


  Identifying whether an utterance is a statement, question, greeting, and so
forth is integral to effective automatic understanding of natural dialog.
Little is known, however, about how such dialog acts (DAs) can be automatically
classified in truly natural conversation. This study asks whether current
approaches, which use mainly word information, could be improved by adding
prosodic information. The study is based on more than 1000 conversations from
the Switchboard corpus. DAs were hand-annotated, and prosodic features
(duration, pause, F0, energy, and speaking rate) were automatically extracted
for each DA. In training, decision trees based on these features were inferred;
trees were then applied to unseen test data to evaluate performance.
Performance was evaluated for prosody models alone, and after combining the
prosody models with word information -- either from true words or from the
output of an automatic speech recognizer. For an overall classification task,
as well as three subtasks, prosody made significant contributions to
classification. Feature-specific analyses further revealed that although
canonical features (such as F0 for questions) were important, less obvious
features could compensate if canonical features were removed. Finally, in each
task, integrating the prosodic model with a DA-specific statistical language
model improved performance over that of the language model alone, especially
for the case of recognized words. Results suggest that DAs are redundantly
marked in natural conversation, and that a variety of automatically extractable
prosodic features could aid dialog processing in speech applications.

</DOC>
<DOC>
<DOCNO> 85108 </DOCNO>
Second Law of Black Hole Mechanics for all 2d Dilaton Theories


  It is shown that all generalized two--dimensional dilaton theories with
arbitrary matter content (with a curvature independent coupling to gravity) do
not only obey a first law of black hole mechanics (which follows from Wald's
general considerations, if the entropy S is defined appropriately), but also a
second law: \delta S \ge 0 provided only that the null energy condition holds
and that, loosely speaking, for late times a stationary state is assumed. Also
any two-dimensional f(R)--theory is covered. This generalizes a previous proof
of Frolov [1] to a much wider class of theories.

</DOC>
<DOC>
<DOCNO> 99911 </DOCNO>
Resolution graphs of some surface singularities I. (cyclic coverings)


  The article starts with some introductory material about resolution graphs of
normal surface singularities (definitions, topological/homological properties,
etc). We then discuss the case when the normal surface singularity is an N-fold
cyclic covering of a surface germ, branched along a curve given by the germ of
an analytic function f. We present non-trivial examples in order to show that
from the embedded resolution graph G of f in general it is not possible to
recover the resolution graph of the cyclic covering. The main results are the
construction of a ``universal covering graph'' from the topology of the germ f,
and the completely combinatorial construction of the resolution graph of cyclic
coverings from this universal graph of f and the integer N. For this we also
prove some purely graph-theoretical classification theorems of ``covering
graphs''. In the last part, we connect the properties of the universal covering
graph with the topological invariants of f, e.g. with the nilpotent part of its
algebraic monodromy.

</DOC>
<DOC>
<DOCNO> 117261 </DOCNO>
Pickoff and spin-conversion quenchings of ortho-positronium in oxygen


  The quenching processes of the thermalized ortho-positronium(o-Ps) on an
oxygen molecule have been studied by the positron annihilation age-momentum
correlation techinique(AMOC). The Doppler broadening spectrum of the 511 keV
gamma-rays from the 2gamma annihilation of o-Ps in O_2 has been measured as a
function of the o-Ps age. The rate of the quenching, consisting of the pickoff
and the spin-conversion, is estimated from the positron lifetime spectrum. The
ratio of the pickoff quenching rate to the spin-conversion rate is deduced from
the Doppler broadening of the 511 keV gamma-rays from the annihilation of the
o-Ps. The pickoff parameter ^1Z_eff, the effective number of the electrons per
molecule which contribute to the pickoff quenching, for O_2 is determined to be
0.6 +- 0.4. The cross-section for the elastic spin-conversion quenching is
determined to be (1.16 +- 0.01) * 10^{-19} cm^2.

</DOC>
<DOC>
<DOCNO> 14166 </DOCNO>
Quest for Rare Events in three-dimensional Mesoscopic Disordered Metals


  The study reports on the first large statistics numerical experiment
searching for rare eigenstates of anomalously high amplitudes in
three-dimensional diffusive metallic conductors. Only a small fraction of a
huge number of investigated eigenfunctions generates the far asymptotic tail of
their amplitude distribution function. The relevance of the relationship
between disorder and spectral averaging, as well as of the quantum transport
properties of the investigated mesoscopic samples, for the numerical
exploration of eigenstate statistics is divulged. The quest provides exact
results to serve as a reference point in understanding the limits of
approximations employed in different analytical predictions, and thereby the
physics (quantum vs semiclassical) behind large deviations from the universal
predictions of random matrix theory.

</DOC>
<DOC>
<DOCNO> 119230 </DOCNO>
Planet formation is unlikely in equal mass binary systems with a ~ 50 AU


  We show that planet formation via both gravitational collapse and core
accretion is unlikely to occur in equal mass binary systems with moderate (~ 50
AU) semi-major axes. Internal thermal energy generation in the disks is
sufficient to heat the gas everywhere so that spiral structures quickly decay
rather than grow or fragment. This same heating will inhibit dust coagulation
because the temperatures rise above the vaporization temperatures of many
volatile materials. We consider other processes not included in the model and
conclude that our temperatures are conservatively estimated (low), i.e. planet
formation is less likely in real systems than in the model.

</DOC>
<DOC>
<DOCNO> 9879 </DOCNO>
Normal Stress Distribution of Rough Surfaces in Contact


  We study numerically the stress distribution on the interface between two
thick elastic media bounded by interfaces that include spatially correlated
asperities. The interface roughness is described using the self-affine
topography that is observed over a very wide range of scales from fractures to
faults. We analyse the correlation properties of the normal stress distribution
when the rough surfaces have been brought into full contact. The self affinity
of the rough surfaces is described by a Hurst exponent H. We find that the
normal stress field is also self affine, but with a Hurst exponent H-1.
Fluctations of the normal stress are shown to be important, especially at local
scales with anti-persistent correlations.

</DOC>
<DOC>
<DOCNO> 152303 </DOCNO>
The global phase diagram of a modular invariant two dimensional


  A generalization of the Coulomb Gas model with modular SL(2, Z)-symmetry
allows for a discrete infinity of phases which are characterized by the
condensation of dyonic pseudoparticles and the breaking of parity and time
reversal. Here we study the phase diagram of such a model by using
renormalization group techniques. Then the symmetry SL(2,Z) acting on the
two-dimensional parameter space gives us a nested shape of its global phase
diagram and all the infrared stable fixed points. Finally we propose a
connection with the 2-dimensional Conformal Field Theory description of the
Fractional Quantum Hall Effect.

</DOC>
<DOC>
<DOCNO> 102825 </DOCNO>
Combinatorics of the $\hat{sl}_2$ Spaces of Coinvariants III


  We give the fermionic character formulas for the spaces of coinvariants
obtained from level $k$ integrable representations of $\hat{\mathfrak sl}_2$.
We establish the functional realization of the spaces dual to the coinvariant
spaces. We parameterize functions in the dual spaces by rigged partitions, and
prove the recursion relations for the sets of rigged partitions.

</DOC>
<DOC>
<DOCNO> 68549 </DOCNO>
Parton densities for heavy quarks


  We compare parton densities for heavy quarks.

</DOC>
<DOC>
<DOCNO> 121776 </DOCNO>
Prospects of observing pulsed radiation from gamma-ray pulsars with


  Observations and theoretical studies have demonstrated that the pulsed
spectra of all gamma-ray pulsars terminate at energies below a few hundred GeV.
In most cases we expect this cutoff energy E_o to be around 10 GeV. Only with
next generation ground-based gamma-ray telescopes, which are expected to have
non-zero trigger probabilities near 10 GeV, can we expect to detect pulsations.
The large gamma-ray fluxes below E_o, together with the associated sharp pulse
profiles, compensate for the lack of imaging capability near threshold. For
H.E.S.S. we find that the pulsed component of PSR B1706-44 should be detectable
near threshold, whereas the unidentified GeV EGRET sources should be detectable
if the superexponential cutoff energy is larger that approximately 30 GeV for
relatively hard pulsar photon spectra (~E^-1.5).

</DOC>
<DOC>
<DOCNO> 117539 </DOCNO>
Rings in the Planetesimal Disk of Beta Pic


  The nearby main sequence star Beta Pictoris is surrounded by an edge-on disk
of dust produced by the collisional erosion of larger planetesimals. Here we
report the discovery of substructure within the northeast extension of the disk
midplane that may represent an asymmetric ring system around Beta Pic. We
present a dynamical model showing that a close stellar flyby with a quiescient
disk of planetesimals can create such rings, along with previously unexplained
disk asymmetries. Thus we infer that Beta Pic's planetesimal disk was highly
disrupted by a stellar encounter in the last hundred thousand years.

</DOC>
<DOC>
<DOCNO> 39889 </DOCNO>
Search for an invisibly decaying Higgs boson in e^+e^- collisions at


  A search for a Higgs boson decaying into invisible particles is performed
using the data collected at LEP by the L3 experiment at centre-of-mass energies
of 183 GeV and 189 GeV. The integrated luminosities are respectively 55.3 pb^-1
and 176.4 pb^-1. The observed candidates are consistent with the expectations
from Standard Model processes. In the hypothesis that the production cross
section of this Higgs boson equals the Standard Model one and the branching
ratio into invisible particles is 100%, a lower mass limit of 89.2 GeV is set
at 95% confidence level.

</DOC>
<DOC>
<DOCNO> 9415 </DOCNO>
Finite-temperature properties of PZT alloys from first principles


  A first-principles-derived approach is developed to study finite-temperature
properties of PbZr{1-x}Ti{x}O3 (PZT) solid solutions near the morphotropic
phase boundary (MPB). Structural and piezoelectric predictions are in excellent
agreement with experimental data and direct first-principles results. A
low-temperature monoclinic phase is confirmed to exist, and is demonstrated to
act as a bridge between the well-known tetragonal and rhombohedral phases
delimiting the MPB. A successful explanation for the large piezoelectricity
found in PZT ceramics is also provided.

</DOC>
<DOC>
<DOCNO> 13129 </DOCNO>
Hole concentration dependence of the magnetic moment in superconducting


  Recent neutron scattering measurements on the La2-xSrxCuO4 system have
revealed a drastic change of the incommensurate static spin correlations from
diagonal in the insulating region to parallel in the superconducting region. We
report the doping dependence of the ordered magnetic moment for the hole
concentration region 0.03 <= x <= 0.12, focusing on the relationship between
the static magnetism and the superconductivity. The elastic magnetic
crosssection decreases monotonically with increasing x for 0.03 <= x <= 0.07.
We find that the ordered magnetic moment \mu varies from ~0.18 (x=0.03) to
\~0.06 \mu_B/Cu (x=0.07). No significant anomaly is observed at the
insulator-superconductor boundary (x ~ 0.055). The elastic magnetic
crosssection is enhanced in the vicinity of x=0.12 whose resolution limited
width peaks are observed in neutron scattering measurements and where the
apparent magntic and superconducting transitions coincide.

</DOC>
<DOC>
<DOCNO> 120580 </DOCNO>
Opening the ultra high energy cosmic ray window from the top


  While several arguments can be proposed against the existence of particles
with energy in excess of $(3-5)\times 10^{19}$ eV in the cosmic ray spectrum,
these particles are actually observed and their origin seeks for an
explanation. After a description of the problems encountered in explaining
these ultra-high energy cosmic rays (UHECRs) in the context of astrophysical
sources, we will review the so-called {\it Top-Down} (TD) Models, in which
UHECRs are the result of the decay of very massive unstable particles, possibly
created in the Early Universe. Particular emphasis will be given to the
signatures of the TD models, likely to be accessible to upcoming experiments
like Auger.

</DOC>
<DOC>
<DOCNO> 174573 </DOCNO>
Monitoring of the accelerator beam distributions for internal target


  We describe a direct method for monitoring the geometrical dimensions of a
synchrotron beam at the target position for internal target installations. The
method allows for the observation of the proton beam size as well as the
position of the beam relative to the target. As a first demonstration of the
technique, we present results obtained by means of the COSY-11 detection system
installed at the cooler synchrotron COSY. The influence of the stochastic
cooling on the COSY proton beam dimensions is also investigated.

</DOC>
<DOC>
<DOCNO> 40445 </DOCNO>
The "Golden Mode" at the Upgraded Tevatron?


  The exiatence of extra SM families results in essential enhancement of the
gluon fusion channel Higgs boson production at hadron colliders. In this case,
the SM Higgs boson can be seen at the upgraded Tevatron via the "golden mode"
(H-->4l) for certain values of its mass.

</DOC>
<DOC>
<DOCNO> 119257 </DOCNO>
On the nonthermal X-ray emission in blazar jets


  We consider particle acceleration to high energy via diffusive shock
acceleration in a simple, self-consistent shock in jet model for blazars.
Electrons are assumed to be accelerated at a shock front in relativistic jets
and radiate synchrotron emission in a post-shock region. The full time, space
and momentum dependence of the electron distribution function is used for a
calculation of the nonthermal synchrotron spectra. We discuss the evolution of
the spectral index by varying the rate at which particles enter the
acceleration process. The results indicate that the synchrotron spectral index
displays a characteristic looplike behaviour with intensity (as has been
observed in several blazars), where the orientation of the loop depends on
whether the acceleration time scale is comparable to the synchrotron cooling
time scale or not. We show that our model provides a good fit to the observed
evolution of the spectral index of Mkn 421 during a flare in 1994.

</DOC>
<DOC>
<DOCNO> 10467 </DOCNO>
Non conservative Abelian sandpile model with BTW toppling rule


  A non conservative Abelian sandpile model with BTW toppling rule introduced
in [Tsuchiya and Katori, Phys. Rev. E {\bf 61}, 1183 (2000)] is studied. Using
a scaling analysis of the different energy scales involved in the model and
numerical simulations it is shown that this model belong to a universality
class different from that of previous models considered in the literature.

</DOC>
<DOC>
<DOCNO> 13745 </DOCNO>
End to end distance on contour loops of random gaussian surfaces


  A self consistent field theory that describes a part of a contour loop of a
random Gaussian surface as a trajectory interacting with itself is constructed.
The exponent \nu characterizing the end to end distance is obtained by a Flory
argument. The result is compared with different previuos derivations and is
found to agree with that of Kondev and Henley over most of the range of the
roughening exponent of the random surface.

</DOC>
<DOC>
<DOCNO> 152200 </DOCNO>
Localizing Gravity on a 3-brane in Higher Dimensions


  We present metric solutions in six and higher dimensions with a bulk
cosmological constant, where gravity is localized on a 3-brane. The corrections
to four-dimensional gravity from the bulk continuum modes are power-law
suppressed. Furthermore, the introduction of a bulk ``hedgehog'' magnetic field
leads to a regular geometry, and can localize gravity on the 3-brane with
either positive, zero or negative bulk cosmological constant.

</DOC>
<DOC>
<DOCNO> 169659 </DOCNO>
Quantum computation with mesoscopic superposition states


  We present a strategy to engineer a simple cavity-QED two-bit universal
quantum gate using mesoscopic distinct quantum superposition states. The
dissipative effect on decoherence and amplitude damping of the quantum bits are
analyzed and the critical parameters are presented.

</DOC>
<DOC>
<DOCNO> 84455 </DOCNO>
Special Properties of Five Dimensional BPS Rotating Black Holes


  Supersymmetric, rotating, asymptotically flat black holes with a regular
horizon are rare configurations in String Theory. One example is known in five
spacetime dimensions, within the toroidal compactification of type IIB string
theory. Such special solution is allowed by the existence of a Chern-Simons
coupling in the Supergravity theory and by the possibility of imposing a self
duality condition on the `rotation 2-form'. We explore three peculiar features
of such black holes: 1) Oxidising to D=10 the five dimensional configuration
may be interpreted as a system of $D1-D5$ branes with a Brinkmann wave
propagating along their worldvolume. Unlike its five dimensional Kaluza-Klein
compactification, the universal covering space of this manifold has no
causality violations. In other words, causal anomalies can be solved in higher
dimensions. From the dual SCFT viewpoint, the causality bound for the
compactified spacetime arises as the unitarity bound; 2) The vanishing of the
scattering cross section for uncharged scalars and sufficiently high angular
momentum of the background is shown still to hold at the level of charged
interactions. The same is verified when a non-minimal coupling to the geometry
is used. Therefore, the `repulson' behaviour previously found is universal for
non accelerated observers; 3) The solutions are shown to have a non-standard
gyromagnetic ratio of $g=3$. In contrast, the superpartners of a static, BPS,
five dimensional black hole have $g=1$. At the semi-classical level, we find
that a Dirac fermion propagating in the rotating hole background has $g=2\pm1$,
depending on the spinor direction of the fermion being parallel to Killing or
`anti-Killing' spinors.

</DOC>
<DOC>
<DOCNO> 13674 </DOCNO>
Resonantly enhanced nonlinear optics in semiconductor quantum wells: An


  A novel class of coherent nonlinear optical phenomena, involving induced
transparency in quantum wells, is considered in the context of a particular
application to sensitive long-wavelength infrared detection. It is shown that
the strongest decoherence mechanisms can be suppressed or mitigated, resulting
in substantial enhancement of nonlinear optical effects in semiconductor
quantum wells.

</DOC>
<DOC>
<DOCNO> 12921 </DOCNO>
Coexistent quantum and classical aspects of magnetization plateaux in


  Magnetization process of ferrimagnetic Heisenberg chains of alternating spins
are theoretically studied. The size scaling analysis with the exact
diagonalization of finite systems for ($S$,$s$)=(3/2,1) and (2,1) indicates a
multi-plateau structure in the ground-state magnetization curve for $S$ and $s$
$>1/2$. The first plateau at the spontaneous magnetization can be explained by
a classical origin, that is the Ising gap. In contrast, the second or higher
one must be originated to the quantization of the magnetization. It is also
found that all the $2s$ plateaux, including the classical and quantum ones,
appear even in the isotropic case with no bond alternation.

</DOC>
<DOC>
<DOCNO> 151586 </DOCNO>
Can We Live on the Brane in Schwarzschild-anti de Sitter Black Hole?


  The model of d5 higher derivative (HD) gravity admitting Schwarzschild--anti
de Sitter Black Hole (S-AdS BH) as exact solution is considered. The surface
counterterms are added to the complete action, they are fixed by the condition
of finiteness of bulk AdS spacetime when brane goes to infinity. As a result
the brane (observable Universe) is defined dynamically in terms of d5 theory
parameters (brane tension is fixed). Brane radius is always bigger than horizon
radius and the 4d Universe itself could be static or inflationary. Natural
ganeralization of this model gives warped compactification (with dynamically
generated brane) in the next-to-leading order of AdS/CFT correspondence.

</DOC>
<DOC>
<DOCNO> 9311 </DOCNO>
The choice of the symmetry group for the cuprates


  Following our recent conjecture to model the phenomenona of
antiferromagnetism and superconductivity by quantum symmetry groups, we discuss
in the present note the choice of the classical symmetry group underlying the
quantum group.
  Keeping in mind the degrees of freedom arising from spin, charge, and lattice
we choose the classical group as SO(7). This choice is also motivated to
accomodate the several competing phases which are or may be present in these
and related materials, such as stripe phase [mesoscopically ordered phase],
Luttinger liquids, nearly antiferromagnetic Fermi liquids, charge-ordered Fermi
liquids, glassy phase, stringy phase and perhaps more. The existence and the
behavior of pseudo-gap and lattice distortion are also an important
consideration.
  We have lumped the charge, spin and lattice-distortion ordering and other
orderings into the psuedogap.

</DOC>
<DOC>
<DOCNO> 122743 </DOCNO>
Mapping potential fields on the surfaces of rapidly rotating stars


  We present a technique that combines Zeeman Doppler imaging (ZDI) principles
with a potential field mapping prescription in order to gain more information
about the surface field topology of rapid rotators. This technique is an
improvement on standard ZDI, which can sometimes suffer from the suppression of
one vector component due to the effects of stellar inclination, poor phase
coverage or lack of flux from dark areas on the surface. Defining a
relationship beween the different vector components allows information from one
component to compensate for reduced information in another. We present
simulations demonstrating the capability of this technique and discuss its
prospects.

</DOC>
<DOC>
<DOCNO> 100986 </DOCNO>
A double bounded key identity for Goellnitz's (big) partition theorem


  Given integers i,j,k,L,M, we establish a new double bounded q-series identity
from which the three parameter (i,j,k) key identity of Alladi-Andrews-Gordon
for Goellnitz's (big) theorem follows if L, M tend to infinity. When L = M, the
identity yields a strong refinement of Goellnitz's theorem with a bound on the
parts given by L. This is the first time a bounded version of Goellnitz's (big)
theorem has been proved. This leads to new bounded versions of Jacobi's triple
product identity for theta functions and other fundamental identities.

</DOC>
<DOC>
<DOCNO> 13310 </DOCNO>
Effective Lorentz Force due to Small-angle Impurity Scattering:


  We show that a scattering rate which varies with angle around the Fermi
surface has the same effect as a periodic Lorentz force on magnetotransport
coefficients. This effect, together with the marginal Fermi liquid inelastic
scattering rate gives a quantitative explanation of the temperature dependence
and the magnitude of the observed Hall effect and magnetoresistance with just
the measured zero-field resistivity as input.

</DOC>
<DOC>
<DOCNO> 9312 </DOCNO>
Lattice models and Landau theory for type II incommensurate crystals


  Ground state properties and phonon dispersion curves of a classical linear
chain model describing a crystal with an incommensurate phase are studied. This
model is the DIFFOUR (discrete frustrated phi4) model with an extra
fourth-order term added to it. The incommensurability in these models may arise
if there is frustration between nearest-neighbor and next-nearest-neighbor
interactions. We discuss the effect of the additional term on the phonon
branches and phase diagram of the DIFFOUR model. We find some features not
present in the DIFFOUR model such as the renormalization of the
nearest-neighbor coupling. Furthermore the ratio between the slopes of the soft
phonon mode in the ferroelectric and paraelectric phase can take on values
different from -2. Temperature dependences of the parameters in the model are
different above and below the paraelectric transition, in contrast with the
assumptions made in Landau theory. In the continuum limit this model reduces to
the Landau free energy expansion for type II incommensurate crystals and it can
be seen as the lowest-order generalization of the simplest Lifshitz-point
model. Part of the numerical calculations have been done by an adaption of the
Effective Potential Method, orginally used for models with nearest-neighbor
interaction, to models with also next-nearest-neighbor interactions.

</DOC>
<DOC>
<DOCNO> 13467 </DOCNO>
Radiative Lifetimes of Single Excitons in Semiconductor Quantum Dots-


  Using time correlated single photon counting combined with temperature
dependent diffraction limited confocal photoluminescence spectroscopy we
accurately determine, for the first time, the intrinsic radiative lifetime of
single excitons confined within semiconductor quantum dots. Their lifetime is
one (two) orders of magnitude longer than the intrinsic radiative lifetime of
single excitons confined in semiconductor quantum wires (wells) of comparable
confining dimensions. We quantitatively explain this long radiative time in
terms of the reduced spatial coherence between the confined exciton dipole
moment and the radiation electromagnetic field.

</DOC>
<DOC>
<DOCNO> 101701 </DOCNO>
Hua system and pluriharmonicity for symmetric irreducible Siegel domains


  We consider the Johnson-Koranyi-Hua system on symmetric Siegel domains of
type two. We prove that all functions which are annihilated by the system and
satisfy an H^2 integrability condition are pluriharmonic. So the situation is
completely different on type two domains than on tube type domains: it was
proved by Johnson and Koranyi that on symmetric tube type domains the system
characterizes Poisson-Szego integrals.

</DOC>
<DOC>
<DOCNO> 151879 </DOCNO>
Lectures on Warped Compactifications and Stringy Brane Constructions


  In these lectures, two different aspects of brane world scenarios in 5d
gravity or string theory are discussed. In the first two lectures, work on how
warped compactifications of 5d gravity theories can change the guise of the
hierarchy problem and the cosmological constant problem is reviewed, and a
discussion of several issues which remain unclear in this context is provided.
In the next two lectures, microscopic constructions in string theory which
involve D-branes wrapped on cycles of Calabi-Yau manifolds are described. The
focus is on computing the superpotential in the brane worldvolume field theory.
Such calculations may be a necessary step towards understanding e.g.
supersymmetry breaking and moduli stabilization in stringy realizations of such
scenarios, and are of intrinsic interest as probes of the quantum geometry of
the Calabi-Yau space.

</DOC>
<DOC>
<DOCNO> 11093 </DOCNO>
Macroscopic dielectric response of the metallic particles embedded in


  A theoretical approach is proposed to calculate an effective dielectric
constant of a matrix disperse system (MDS) of metallic particles (spheres)
randomly distributed and embedded in a uniform dielectric medium. Deviations
from the well-known Maxwell Garnett formula have been observed. The effective
dielectric constant for different volume fractions of the embedded particles is
considered as well as the dependence on pair interaction between particles, and
the relation between sizes of each pair of particles. The problem is solved in
the electrostatic approximation.

</DOC>
<DOC>
<DOCNO> 12654 </DOCNO>
A Unified Grand Canonical Description of The Nonextensive


  In this paper, the particles of quantum gases, that is, bosons and fermions
are regarded as g-ons which obey fractional exclusion statistics. With this
point of departure the thermostatistical relations concerning the Bose and
Fermi systems are unified under the g-on formulation where a fractal approach
is adopted. The fractal inspired entropy, the partition function, distribution
function, the thermodynamics potential and the total number of g-ons have been
found for a grand canonical g-on system. It is shown that from the g-on
formulation; by a suitable choice of the parameters of the nonextensivity q,
the parameter of the fractional exclusion statistics g, nonextensive Tsallis as
well as extensive standard thermostatistical relations of the Bose and Fermi
systems are recovered.

</DOC>
<DOC>
<DOCNO> 12620 </DOCNO>
Thermodynamics and optical conductivity of unconventional spin density


  We consider the possibility of formation of an unconventional spin density
wave (USDW) in quasi-one dimensional electronic systems. In analogy with
unconventional superconductivity, we develop a mean field theory of SDW
allowing for the momentum dependent gap $\Delta({\bf k})$ on the Fermi surface.
Conditions for the appearence of such a low temperature phase are investigated.
The excitation spectrum and basic thermodynamic properties of the model are
found to be very similar to those of d-wave superconductors in spite of the
different topology of their Fermi surfaces. Several correlation functions are
calculated, and the frequency dependent conductivity is evaluated for various
gap functions. The latter is found to reflect the maximum gap value, however
with no sharp onset for absorbtion.

</DOC>
<DOC>
<DOCNO> 152391 </DOCNO>
Classification of Conformality Models Based on Nonabelian Orbifolds


  A systematic analysis is presented of compactifications of the IIB
superstring on $AdS_5 \times S^5/\Gamma$ where $\Gamma$ is a non-abelian
discrete group. Every possible $\Gamma$ with order $g \leq 31$ is considered.
There exist 45 such groups but a majority cannot yield chiral fermions due to a
certain theorem that is proved. The lowest order to embrace the nonSUSY
standard $SU(3) \times SU(2) \times U(1)$ model with three chiral families is
$\Gamma = D_4 \times Z_3$, with $g=24$; this is the only successful model found
in the search. The consequent uniqueness of the successful model arises
primarily from the scalar sector, prescribed by the construction, being
sufficient to allow the correct symmetry breakdown.

</DOC>
<DOC>
<DOCNO> 116820 </DOCNO>
Four-wave mixing at maximum coherence and eliminated Doppler broadening


  New feasibity of coherent quantum control of four-wave mixing processes in a
resonant Doppler-broadened medium are studied. We propose a technique which
enables one to enhance the quantum efficiency of nonlinear optical conversion.
At the same time, it allows one to decrease the required intensities of the
fundamental beams compared to those necessary in the approach based on coherent
population trapping. The major outcomes of the analysis are illustrated with
numerical simulation addressed within a practical medium.

</DOC>
<DOC>
<DOCNO> 11674 </DOCNO>
Path-Integral Formulation of Stochastic Processes for the Exclusive


  We present the systematic formalism to derive the path-integral formulation
for the hard-core particle systems far from equilibrium. Writing the master
equation for a stochastic process of the system in terms of the annihilation
and creation operators with the mixed commutation relations, we find the
Kramers-Moyal coefficients for the corresponding Fokker-Planck equation (FPE)
and the stochastic differential equation (SDE) is derived by connecting these
coefficients in the FPE to those in the SDE. Finally, the SDE is mapped onto
the field-theory using the path-integral, giving the field-theoretic action
which may be analyzed by the renormalization group method. We apply this
formalism to the two-species reaction-diffusion system with the drift, finding
a universal decay expoent for the long-time behavior of the average
concentration of particles in arbitrary dimensions.

</DOC>
<DOC>
<DOCNO> 12581 </DOCNO>
Role of entropy barriers for diffusion in the periodic potential


  Diffusion of a particle in the N-dimensional external potential which is
periodic in one dimension and unbounded in the other N-1 dimensions is
investigated. We find an analytical expression for the overdamped diffusion and
study numerically the cases of moderate and low damping. We show that in the
underdamped limit, the multi-dimensional effects lead to reduction (comparing
with the one-dimensional motion) of jump lengths between subsequent trapping of
the atom in bottoms of the external periodic potential. As application we
consider the diffusion of a dimer adsorbed on the crystal surface.

</DOC>
<DOC>
<DOCNO> 150864 </DOCNO>
Field Theory on Noncommutative Space-Time and the Deformed Virasoro


  We consider a field theoretical model on the noncommutative cylinder which
leads to a discrete-time evolution. Its Euclidean version is shown to be
equivalent to a model on the complex $q$-plane. We reveal a direct link between
the model on a noncommutative cylinder and the deformed Virasoro algebra
constructed earlier on an abstract mathematical background. As it was shown,
the deformed Virasoro generators necessarily carry a second index (in addition
to the usual one), whose meaning, however, remained unknown. The present field
theoretical approach allows one to ascribe a clear meaning to this second
index: its origin is related to the noncommutativity of the underlying
space-time. The problems with the supersymmetric extension of the model on a
noncommutative super-space are briefly discussed.

</DOC>
<DOC>
<DOCNO> 85243 </DOCNO>
Ricci Collineations of the Bianchi Types I and III, and Kantowski-Sachs


  Ricci collineations of the Bianchi types I and III, and Kantowski-Sachs
space- times are classified according to their Ricci collineation vector (RCV)
field of the form (i)-(iv) one component of $\xi^a (x^b)$ is nonzero, (v)-(x)
two components of $\xi^a (x^b)$ are nonzero, and (xi)-(xiv) three components of
$\xi^a (x^b)$ are nonzero. Their relation with isometries of the space-times is
established. In case (v), when $det(R_{ab}) = 0$, some metrics are found under
the time transformation, in which some of these metrics are known, and the
other ones new. Finally, the family of contracted Ricci collineations (CRC) are
presented.

</DOC>
<DOC>
<DOCNO> 151869 </DOCNO>
Stationary BPS Solutions in N=2 Supergravity with R^2-Interactions


  We analyze a broad class of stationary solutions with residual N=1
supersymmetry of four-dimensional N=2 supergravity theories with terms
quadratic in the Weyl tensor. These terms are encoded in a holomorphic
function, which determines the most relevant part of the action and which plays
a central role in our analysis. The solutions include extremal black holes and
rotating field configurations, and may have multiple centers. We prove that
they are expressed in terms of harmonic functions associated with the electric
and magnetic charges carried by the solutions by a proper generalization of the
so-called stabilization equations. Electric/magnetic duality is manifest
throughout the analysis.
  We also prove that spacetimes with unbroken supersymmetry are fully
determined by electric and magnetic charges. This result establishes the
so-called fixed-point behavior according to which the moduli fields must flow
towards certain prescribed values on a fully supersymmetric horizon, but now in
a more general context with higher-order curvature interactions. We briefly
comment on the implications of our results for the metric on the moduli space
of extremal black hole solutions.

</DOC>
<DOC>
<DOCNO> 68720 </DOCNO>
Quintessence Axion Potential Induced by Electroweak Instanton Effects


  Recent cosmological observations suggest the presence of small but nonzero
cosmological constant $\Lambda_{cos}^4 \simeq (2 \times 10^{-3} eV)^4$. It is
an intriguing possibility that such a small cosmological constant is supplied
by the potential energy density of an ultralight axion-like field (called as
quintessence axion). If this axion couples to the electroweak gauge fields, its
potential may be generated by the electroweak instanton effects. We calculate
the axion potential assuming the supersymmetric standard model and obtain a
surprising result that the induced energy density of the quintessence axion
field is very close to the value suggested from the observations.

</DOC>
<DOC>
<DOCNO> 99861 </DOCNO>
Between Sobolev and Poincar\'e


  We establish a family of functional inequalities interpolating between the
classical logarithmic Sobolev and Poincar\'e inequalities. We prove that they
imply the concentration of measure phenomenon intermediate between Gaussian and
exponential. Our bounds are close to optimal.

</DOC>
<DOC>
<DOCNO> 8290 </DOCNO>
Scaling in a cellular automaton model of earthquake faults


  We present theoretical arguments and simulation data indicating that the
scaling of earthquake events in models of faults with long-range stress
transfer is composed of at least three distinct regions. These regions
correspond to three classes of earthquakes with different underlying physical
mechanisms. In addition to the events that exhibit scaling, there are larger
``breakout'' events that are not on the scaling plot. We discuss the
interpretation of these events as fluctuations in the vicinity of a spinodal
critical point.

</DOC>
<DOC>
<DOCNO> 170712 </DOCNO>
A general computer program for the Bell detection loophole


  The difference between ideal experiments to test Bell's weak nonlocality and
the real experiments leads to loopholes. Ideal experiments involve either
inequalities (Bell) or equalities (Greenberger, Horne, Zeilinger). Every real
experiment has its own critical inequalities, which are almost all more
complicated than the corresponding ideal inequalities and equalities. If one of
these critical inequalities is violated, then the detection loophole is closed,
with no further assumptions. If all the critical inequalities are satisfied,
then it remains open, unless further assumptions are made. The computer program
described here and published on the website
http://www.strings.ph.qmw.ac.uk/QI/main.htm obtains the critical inequalities
for any real experiment, given the number of allowed settings of the angles and
the corresponding possible output signals for a single run. Given all the
necessary conditional probabilities or rates, it tests whether all these
inequalities are satisfied.

</DOC>
<DOC>
<DOCNO> 116756 </DOCNO>
Fixed energy inversion of 5 eV e-Xe atom scattering


  Fixed energy inverse scattering theory has been used to define central and
spin-orbit Schr\"odinger potentials for the scattering of 5 eV polarized
electrons from Xe atoms. The results are typical for a range of such data;
including energies above threshold when the potentials become complex. The
phase shifts obtained from an analysis of the measured differential cross
section and analyzing power has been used as input data. Both semi-classical
(WKB) and fully quantal inversion methods have been used to extract central and
spin-orbit interactions. The analysis shows that information additional to the
set of input phase shifts extracted from this (and similar) data may be needed
to ascertain physical potentials.

</DOC>
<DOC>
<DOCNO> 8453 </DOCNO>
Static and dynamical properties of a supercooled liquid confined in a


  We present the results of a Molecular Dynamics computer simulation of a
binary Lennard-Jones liquid confined in a narrow pore. The surface of the pore
has an amorphous structure similar to that of the confined liquid. We find that
the static properties of the liquid are not affected by the confinement, while
the dynamics changes dramatically. By investigating the time and temperature
dependence of the intermediate scattering function we show that the dynamics of
the particles close to the center of the tube is similar to the one in the
bulk, whereas the characteristic relaxation time tau_q(T,rho) of the
intermediate scattering function at wavevector q and distance rho from the axis
of the pore increases continuously when approaching the wall, leading to an
apparent divergence in the vicinity of the wall. This effect is seen for
intermediate temperatures down to temperatures close to the glass transition.
The rho-dependence of tau_q(T,rho) can be described by an empirical law of the
form tau_q(T,\rho)=f_q(T) exp [Delta_q/(rho_p-rho)], where Delta_q and \rho_q
are constants, and f_q(T) is the only parameter which shows a significant
temperature dependence.

</DOC>
<DOC>
<DOCNO> 116622 </DOCNO>
Solitary coherent structures in viscoelastic shear flow: computation and


  Starting from stationary bifurcations in Couette-Dean flow, we compute
nontrivial stationary solutions in inertialess viscoelastic circular Couette
flow. These solutions are strongly localized vortex pairs, exist at arbitrarily
large wavelengths, and show hysteresis in the Weissenberg number, similar to
experimentally observed ``diwhirl'' patterns. Based on the computed velocity
and stress fields, we elucidate a heuristic, fully nonlinear mechanism for
these flows. We propose that these localized, fully nonlinear structures
comprise fundamental building blocks for complex spatiotemporal dynamics in the
flow of elastic liquids.

</DOC>
<DOC>
<DOCNO> 69836 </DOCNO>
SO(10)-Inspired See-Saw Mechanism


  We determine the nu_{R} Majorana mass matrix from the experimental data on
neutrino oscillations in the framework of a see-saw SO(10) model, where we
impose the condition (M^R)_{33} = 0 to avoid too large fine-tunings in the
see-saw formula. We find a class of solutions with the two lowest neutrino
masses almost degenerate and the scale of the matrix elements of M^R in the
range 10^{11} -10^{12} GeV in agreement with Pati-Salam intermediate symmetry.
We find also solutions with smaller neutrino masses, for which the scale of M_R
depends on the solution to the "solar neutrino problem" and on the value of the
component of \nu_e along the highest mass eigenstate, U_{e3}.

</DOC>
<DOC>
<DOCNO> 70336 </DOCNO>
Sfermion production at photon colliders


  We calculate total and differential cross sections for sfermion production in
$e^+e^-$ annihilation and in photon-photon collisions with arbitrary photon
polarization. The total cross section at a polarized photon collider is shown
to be larger than the $e^+e^-$ annihilation cross section up to the kinematic
limit of the photon collider.

</DOC>
<DOC>
<DOCNO> 84127 </DOCNO>
How to test vector nature of gravity


  The covariant scheme is proposed to couple gravity and electrodynamics in
pseudo-Riemannian four-spaces with electromagnetic connections. Novel dynamics
of the extended charge and electromagnetic dilation-compression of its proper
time can be tested in non-relativistic experiments. The vector equations
acknowledge unified photon waves without metric modulations of flat laboratory
space.

</DOC>
<DOC>
<DOCNO> 178927 </DOCNO>
Proton fraction in neutron stars


  The proton fraction in ${\sl \beta}$-stable neutron stars is investigated
within the framework of the Skyrme-Hartree-Fock theory using the extended
Skyrme effective interaction for the first time. The calculated results show
that the proton fraction disappears at high density, which implies that the
pure neutron matter may exist in the interior of neutron stars. The
incompressibility of the nuclear equation of state is shown to be more
important to determine the proton fraction. Meanwhile, it is indicated that the
addition of muons in neutron stars will change the proton fraction. It is also
found that the higher-order terms of the nuclear symmetry energy have obvious
effects on the proton fraction and the parabolic law of the nuclear symmetry
energy is not enough to determine the proton fraction.

</DOC>
<DOC>
<DOCNO> 169860 </DOCNO>
Does Quantum Nonlocality Exist? Bell's Theorem and the Many-Worlds


  Quantum nonlocality may be an artifact of the assumption that observers obey
the laws of classical mechanics, while observed systems obey quantum mechanics.
I show that, at least in the case of Bell's Theorem, locality is restored if
observed and observer are both assumed to obey quantum mechanics, as in the
Many-Worlds Interpretation. Using the MWI, I shall show that the apparently
"non-local" expectation value for the product of the spins of two widely
separated particles --- the "quantum" part of Bell's Theorem --- is really due
to a series of three purely local measurements. Thus, experiments confirming
"nonlocality" are actually confirming the MWI.

</DOC>
<DOC>
<DOCNO> 11067 </DOCNO>
Singularity Cancellation in Fermion Loops through Ward Identities


  Recently Neumayr and Metzner have shown that the connected N-point density-
correlation functions of the two-dimensional and the one-dimensional Fermi gas
at one-loop order generically vanish/are regular in the small momentum/small
energy-momentum limits. Their result is based on an explicit analysis in the
sequel of results of Feldman et al.[2]. In this note we use Ward identities to
give a proof of the same fact - in a considerably shortened and simplified way
- for any dimension of space.

</DOC>
<DOC>
<DOCNO> 101337 </DOCNO>
Stability of solutions to inverse scattering problems with fixed-energy


  A review of the author's results is given. Inversion formulas and stability
estimates for the solutions to 3D inverse scattering problems with fixed-energy
data are obtained. Inversions of exact and noisy data are stidied. The inverse
potential scattering problem is discussed in detail, inversion formulas are
derived and error estimates are obtained. Inverse obstacle scattering problem
with data at a fixed frequency is studied. Uniqueness theorems and stability
estimates are obtained.
  Inverse geophysical scattering problem is discussed. An algorithm for
computing the Dirichlet-to-Neumann map from the scattering amplitude and vicxe
versa is obtained. An analytical example of non-uniqueness of the solution to a
3D inverse geophysical problem is constructed. An inverse problem for a
parabolic equation is discussed.

</DOC>
<DOC>
<DOCNO> 11818 </DOCNO>
Spin-charge separation in the single hole doped Mott antiferromagnet


  The motion of a single hole in a Mott antiferromagnet is investigated based
on the t-J model. An exact expression of the energy spectrum is obtained, in
which the irreparable phase string effect [Phys. Rev. Lett. 77, 5102 (1996)] is
explicitly present. By identifying the phase string effect with spin backflow,
we point out that spin-charge separation must exist in such a system: the doped
hole has to decay into a neutral spinon and a spinless holon, together with the
phase string. We show that while the spinon remains coherent, the holon motion
is deterred by the phase string, resulting in its localization in space. We
calculate the electron spectral function which explains the line shape of the
spectral function as well as the ``quasiparticle'' spectrum observed in
angle-resolved photoemission experiments. Other analytic and numerical
approaches are discussed based on the present framework.

</DOC>
<DOC>
<DOCNO> 151511 </DOCNO>
BFT Embedding of Interacting Second-Class Systems


  The embedding procedure of Batalin, Fradkin, and Tyutin, which allows to
convert a second-class system into a first-class one, is employed to convert
second-class interacting models. Two cases are considered. One, is the
Self-Dual model minimally coupled to a Dirac fermion field. The other, the
Self-Dual model minimally coupled to a charged scalar field. In both cases,
they are found equivalent interacting Maxwell-Chern-Simons type field theories.
These equivalences are pushed beyond the formal level, by analysing some tree
level probability amplitudes associated to the models.

</DOC>
<DOC>
<DOCNO> 80921 </DOCNO>
Study of the Leutwyler-Smilga regimes: Lessons for full QCD simulations


  Some key points out of my recent study of the characteristic features of the
small ($x \ll 1$), intermediate ($x \simeq 1$) and large ($x \gg 1$)
Leutwyler-Smilga regimes for QCD-type theories in a finite volume ($x = V
\Sigma m$) are presented, and a few immediate consequences for full QCD
simulations are discussed.

</DOC>
<DOC>
<DOCNO> 40395 </DOCNO>
A Method to Search for Local Sources of Short Duration Bursts of


  A method of a search for local sources of superhigh energy gamma rays is
described in the paper.It is shown that the method is more effective then the
usually used method extracting excess from total intensity if gamma ray burst
durations are short.Using the suggested method,the information detected with
the Baksan installation ``Carpet'' during 1992-1996 years was analyzed.An
excess of event numbers was found at the confidence level of 6.5$\sigma$ in the
direction to Mrk 501.

</DOC>
<DOC>
<DOCNO> 85654 </DOCNO>
The Coalescence Rate of Double Neutron Star Systems


  We estimate the coalescence rate of close binaries with two neutron stars
(NS) and discuss the prospects for the detection of NS-NS inspiral events by
ground-based gravitational-wave observatories, such as LIGO. We derive the
Galactic coalescence rate using the observed sample of close NS-NS binaries
(PSR B1913+16 and PSR B1534+12) and examine in detail each of the sources of
uncertainty associated with the estimate. Specifically, we investigate (i) the
dynamical evolution of NS-NS binaries in the Galactic potential and the
vertical scale height of the population, (ii) the pulsar lifetimes, (iii) the
effects of the faint end of the radio pulsar luminosity function and their
dependence on the small number of observed objects, (iv) the beaming fraction,
and (v) the extrapolation of the Galactic rate to extragalactic distances
expected to be reachable by LIGO. We find that the dominant source of
uncertainty is the correction factor (up to about 200) for faint (undetectable)
pulsars. All other sources are much less important, each with uncertainty
factors smaller than 2. Despite the relatively large uncertainty, the derived
coalescence rate is approximately consistent with previously derived upper
limits, and is more accurate than rates obtained from population studies. We
obtain a most conservative lower limit for the LIGO II detection rate of 2
events per year. Our upper limit on the detection rate lies between 300 to more
than 1000 events per year.

</DOC>
<DOC>
<DOCNO> 102449 </DOCNO>
A Distribution Function Arising in Computational Biology


  Karlin and Altschul in their statistical analysis for multiple high-scoring
segments in molecular sequences introduced a distribution function which gives
the probability there are at least r distinct and consistently ordered segment
pairs all with score at least x. For long sequences this distribution can be
expressed in terms of the distribution of the length of the longest increasing
subsequence in a random permutation. Within the past few years, this last
quantity has been extensively studied in the mathematics literature. The
purpose of these notes is to summarize these new mathematical developments in a
form suitable for use in computational biology.

</DOC>
<DOC>
<DOCNO> 121384 </DOCNO>
Accretion Stream Mapping of HU Aquarii


  We present a new mapping algorithm, the "Accretion Stream Mapping (ASM)"
which uses the full phase-coverage of a light curve to derive spatially
resolved intensity distributions along the accretion stream in magnetic
cataclysmic variables of AM Herculis type (polars). The surface of the
accretion stream is approximated as a duodecadon shaped tube. After
successfully testing this method on artificial data we applied it to emission
line light curves of Hbeta, Hgamma and He II lambda 4686 of the bright
eclipsing polar HU Aqr. We find Hydrogen and Helium line emission bright in the
threading region of the stream where the stream couples onto magnetic field
lines. It is particularly interesting, that the stream is bright on the
irradiated side, facing the white dwarf, which highlights the interplay of
collisional and radiative excitation/ionization.

</DOC>
<DOC>
<DOCNO> 169651 </DOCNO>
Optical Realization of Quantum Gambling Machine


  Quantum gambling --- a secure remote two-party protocol which has no
classical counterpart --- is demonstrated through optical approach. A photon is
prepared by Alice in a superposition state of two potential paths. Then one
path leads to Bob and is split into two parts. The security is confirmed by
quantum interference between Alice's path and one part of Bob's path. It is
shown that a practical quantum gambling machine can be feasible by this way.

</DOC>
<DOC>
<DOCNO> 118153 </DOCNO>
VLBI difference astrometry at 43GHz


  From 43GHz VLBA observations of the pair of radio sources 1928+738 and
2007+777 we have demonstrated the feasibility of precision phase-delay
differential astrometric techniques at millimeter wavelengths. For a pair of
sources with 5 degrees separation and high antenna elevations, we have shown
that present astrometric models and millimeter arrays are advanced enough to
model the differential phase-delay to within 2 picoseconds, less than one tenth
of a phase-cycle at 43GHz. The root-mean-square of the differential phase-delay
residuals is dominated by the fluctuations of the atmospheric water vapor. We
have determined the relative position of the observed sources with a precision
twofold better than previous determinations at lower frequencies and, more
importantly, largely free from ambiguous definitions of the reference point on
the structure of the radio sources. Our result makes 43GHz VLBI phase-delay
differential astrometry an ideal tool to study the absolute kinematics of the
highly variable structures of regions near the core of extragalactic radio
sources.

</DOC>
<DOC>
<DOCNO> 39753 </DOCNO>
Measurement of the Running of the Fine-Structure Constant


  Bhabha scattering data recorded at \sqrt{s}=189 GeV by the L3 detector at LEP
are used to measure the running of the effective fine-structure constant for
spacelike momentum transfers. The results are alpha^-1(-2.1 GeV^2) -
alpha^-1(-6.25 GeV^2) = 0.78 +/- 0.26 alpha^-1(-12.25 GeV^2) - alpha^-1(-3434
GeV^2) = 3.80 +/- 1.29, in agreement with theoretical predictions.

</DOC>
<DOC>
<DOCNO> 69587 </DOCNO>
The unintegrated gluon distribution from the CCFM equation


  The gluon distribution f(x, k_t^2,mu^2), unintegrated over the transverse
momentum k_t of the gluon, satisfies the angular-ordered CCFM equation which
interlocks the dependence on the scale k_t with the scale \mu of the probe. We
show how, to leading logarithmic accuracy, the equation can be simplified to a
single scale problem. In particular we demonstrate how to determine the
two-scale unintegrated distribution f(x,k_t^2,mu^2) from knowledge of the
integrated gluon obtained from a unified scheme embodying both BFKL and DGLAP
evolution.

</DOC>
<DOC>
<DOCNO> 84529 </DOCNO>
Uniqueness properties of the Kerr metric


  We obtain a geometrical condition on vacuum, stationary, asymptotically flat
spacetimes which is necessary and sufficient for the spacetime to be locally
isometric to Kerr. Namely, we prove a theorem stating that an asymptotically
flat, stationary, vacuum spacetime such that the so-called Killing form is an
eigenvector of the self-dual Weyl tensor must be locally isometric to Kerr.
Asymptotic flatness is a fundamental hypothesis of the theorem, as we
demonstrate by writing down the family of metrics obtained when this
requirement is dropped. This result indicates why the Kerr metric plays such an
important role in general relativity. It may also be of interest in order to
extend the uniqueness theorems of black holes to the non-connected and to the
non-analytic case.

</DOC>
<DOC>
<DOCNO> 72233 </DOCNO>
The scaling of lepton dipole moments with lepton mass


  The dipole moments of the leptons and quarks are matrices in flavor space,
which can potentially reveal as much about the flavor structure of the theory
as do the mass matrices. The off-diagonal elements of the dipole matrices lead
to flavor-changing decays such as \mu -> e \gamma, while the imaginary parts of
the diagonal elements give rise to electric dipole moments. We analyze the
scaling of the leptonic dipole moments with the lepton masses in theories
beyond the standard model. While in many models the dipole moments scale
roughly as lepton mass, it is shown that simple models exist in which the
dipoles scale as the cube of the mass or in other ways. An explicit example
with cubic scaling is presented, which is motivated on independent grounds from
large angle neutrino oscillation data. Our results have great significance for
the observability of the electric dipole moments of e, \mu and \tau, and the
rare decays \mu -> e \gamma, and \tau -> \mu \gamma and will be tested in
several forthcoming experiments.

</DOC>
<DOC>
<DOCNO> 179047 </DOCNO>
Probing Isospin Dynamics in Halo Nuclei


  Nuclear many-body theory is used to study nuclear matter and finite nuclei at
extreme isospin. In-medium interactions in asymmetric nuclear matter are
obtained from (Dirac-) Brueckner theory. Neutron skin formation in Ni and Sn
isotopes is investigated by relativistic mean-field calculations in DDRH theory
with density dependent meson-nucleon vertices. Applications to light nuclei are
discussed with special emphasis on pairing and core polarization in weakly
bound nuclei. Approaches accounting for continuum coupling in dripline pairing
and core polarization are presented. Calculations for the halo nuclei $^8$B,
$^{11}$Be and $^{19}$C show that shell structures are dissolving when the
driplines are approached. Relativistic breakup data are well described by
eikonal calculations.

</DOC>
<DOC>
<DOCNO> 12903 </DOCNO>
Statistics of the occupation time of renewal processes


  We present a systematic study of the statistics of the occupation time and
related random variables for stochastic processes with independent intervals of
time. According to the nature of the distribution of time intervals, the
probability density functions of these random variables have very different
scalings in time. We analyze successively the cases where this distribution is
narrow, where it is broad with index $\theta <1$, and finally where it is broad
with index $1<\theta <2$. The methods introduced in this work provide a basis
for the investigation of the statistics of the occupation time of more complex
stochastic processes (see joint paper by G. De Smedt, C. Godr\`{e}che, and J.M.
Luck).

</DOC>
<DOC>
<DOCNO> 9503 </DOCNO>
On the value of the Curie temperature in doped manganites


  We have verified that the variational mean field theory approach suggested by
Narimanov and Varma (preprint cond-mat/0002191) being applied to the realistic
two-band model provides a good agreement with experimental data for the Curie
temperature in doped manganites A$_{1-x}$B$_x$MnO$_3$ ($x\simeq{0.3}$). We have
also considered the problem of an interplay between the ferromagnetic and
antiferromagnetic interactions by using the same approach.

</DOC>
<DOC>
<DOCNO> 7620 </DOCNO>
The Hypergraphite: A possible extension of graphitic network


  We propose a class of networks which can be regarded as an extension of the
graphitic network. These networks are constructed so that surface states with
non-bonding character (edge states) are formed in a tight-binding model with
one orbital for each atomic site. Besides, for several networks, the
tight-binding electronic structures become a zero-gap semiconductor. These
properties have been found in the $\pi$-electron system of the graphene. Thus,
we call these networks hypergraphite.

</DOC>
<DOC>
<DOCNO> 69490 </DOCNO>
The Off-Shell Nucleon-Nucleon Amplitude: Why it is Unmeasurable in


  Nucleon-nucleon bremsstrahlung has long been considered a way of getting
information about the off-shell nucleon-nucleon amplitude which would allow one
to distinguish among nucleon-nucleon potentials based on their off-shell
properties. There have been many calculations and many experiments devoted to
this aim. We show here, in contrast to this standard view, that such off-shell
amplitudes are not measurable as a matter of principle. This follows formally
from the invariance of the S-matrix under transformations of the fields. This
result is discussed here and illustrated via two simple models, one applying to
spin zero, and one to spin one half, processes. The latter model is very
closely related to phenomenological models which have been used to study
off-shell effects at electromagnetic vertices.

</DOC>
<DOC>
<DOCNO> 70680 </DOCNO>
Universal features of fluctuations


  Universal scaling laws of fluctuations (the $\Delta$-scaling laws) can be
derived for equilibrium and off-equilibrium systems when combined with the
finite-size scaling analysis. In any system in which the second-order critical
behavior can be identified, the relation between order parameter, criticality
and scaling law of fluctuations has been established and the relation between
the scaling function and the critical exponents has been found.

</DOC>
<DOC>
<DOCNO> 169619 </DOCNO>
Four Atomic Optical Energy Levels as a Two Qubit Quantum Computer


  It is proposed to use four atomic optical energy levels as a two qubit
quantum register. A single Pr3+ atom in a monocrystal LaF3 subjected to
resonant laser irradiation is used as an example to illustrate the
implementation of the universal set of quantum gates. The equilibrium state of
this physical system is a desirable input state for quantum computation and
therefore there is no need for its special preparation procedure.

</DOC>
<DOC>
<DOCNO> 9041 </DOCNO>
Unquenched large orbital magnetic moment in NiO


  Magnetic properties of NiO are investigated by incorporating the spin-orbit
interaction in the LSDA+U scheme. It is found that the large part of orbital
moment remains unquenched in NiO. The orbital moment contributes about mu_L =
0.29 mu_B to the total magnetic moment of M = 1.93 mu_B, as leads to the
orbital-to-spin angular momentum ratio of L/S = 0.36. The theoretical values
are in good agreement with recent magnetic X-ray scattering measurements.

</DOC>
<DOC>
<DOCNO> 121169 </DOCNO>
The distance to the Fornax dwarf galaxy using red clump stars, and the


  I determine a distance to the Fornax dwarf galaxy using stars in the red
clump and at the tip of the red giant branch. They are in very good agreement,
with $\mu_0 = 20.66 mag$. Comparing the magnitudes of the tip of the red giant
branch and of the red clump in Fornax, Carina and the Magellanic Clouds, I
propose a possible solution to the problem of the discrepancy between these two
types of distance measurements.

</DOC>
<DOC>
<DOCNO> 121549 </DOCNO>
Ionized Gas in Damped Lyman Alpha Protogalaxies: I. Model-Independent


  We investigate the kinematics of ionized and neutral gas in a sample of 35
damped Lyman alpha protogalaxies (DLAs) with HIRES on the Keck I 10 m
telescope. Velocity profiles with resolution of ~ 8 km/s are obtained for high
ions such as C IV and Si IV, and for intermediate ions such as Al III.
Combining these profiles with accurate low-ion (e.g., Fe II) profiles, we
investigate the kinematic state of DLAs in the redshift range 1.8 < z < 4.4 by
comparisons between data for various ion pairs.
  We find the DLAs comprise distinct kinematic subsystems: a low ion subsystem
in which the low ions are physically associated with intermediate ions, and a
high subsystem containing neither low nor intermediate ions. The evidence for
two subsystems stems from (a) differences between the widths of the velocity
profiles, (b) misalignment in velocity space between the narrow components
comprising the profiles in each subsystem, and (c) significant dissimilarities
between the mean velocities of the high ion and low ion velocity profiles. In
every case we find that test statistics such as velocity width and various
asymmetry parameters distribute differently for low ions than for high ions.
  Despite misalignment in velocity space, the low and high ion kinematic
subsystems are interrelated. This is indicated by detection of a statistically
significant C IV versus low-ion cross correlation function, and by a systematic
effect where the C IV velocity widths are greater than or equal to the low ion
velocity widths in 29 out of 32 systems. These phenomena are consistent with
the location of the two subsystems in the same potential well.

</DOC>
<DOC>
<DOCNO> 119475 </DOCNO>
Foreground and background dust in star cluster directions


  This paper compares reddening values E(B-V) derived from the stellar content
of 103 old open clusters and 147 globular clusters of the Milky Way with those
derived from DIRBE/IRAS 100 micron dust emission in the same directions. Star
clusters at |b|> 20 show comparable reddening values between the two methods,
in agreement with the fact that most of them are located beyond the disk dust
layer. For very low galactic latitude lines of sight, differences occur in the
sense that DIRBE/IRAS reddening values can be substantially larger, suggesting
effects due to the depth distribution of the dust. The differences appear to
arise from dust in the background of the clusters consistent with a dust layer
where important extinction occurs up to distances from the Plane of ~ 300 pc.
For 3 % of the sample a significant background dust contribution might be
explained by higher dust clouds. We find evidence that the Milky Way dust lane
and higher dust clouds are similar to those of several edge-on spiral galaxies
recently studied in detail by means of CCD imaging.

</DOC>
<DOC>
<DOCNO> 120233 </DOCNO>
The filament of ionized gas in the outskirt of M87


  We report on the filament of ionized gas found at the NE periphery of M87,
the second brightest elliptical galaxy in the Virgo cluster. The object lies at
3.16 arcmin (15.7 kpc) projected distance of the nucleus of M87, and it
coincides in position with the Eastern radio lobe of M87. Long slit
spectroscopy confirmed the gaseus nature of this object, showing Hbeta, [OIII],
[OI], [NII], Halpha and [SII] lines, without any underlying continuum. The
redshift of the object, V = 1170+-25 km/s, agrees with the velocity of M87
itself (V = 1280 km/s), and with the bulk of the ionized material found near
the center of M87. The Halpha flux of this filament corresponds to 1 % of the
ionized material in M87. The radio-optical coincidence together with the
spectral characteristics suggest that the filament is ionized by a shock.

</DOC>
<DOC>
<DOCNO> 71811 </DOCNO>
Update of the direct detection of dark matter and the role of the


  We update our exploration of the MSSM parameter space at the weak scale where
new accelerator and cosmological constraints are respected. The dependence of
WIMP-nucleon cross sections on parameters of the MSSM, uncertainties of the
nucleon structure and other theoretical assumptions like universality and
co-annihilation are considered. In particular, we find that the coannihilation
does not have a significant effect in our analysis in certain regions which are
allowed even with coannihilation. The new cosmological constraint on the relic
neutralino density used in the form $0.1 < \Omega_\chi h^2_0<0.3$ does also not
significantly affect the regions of allowed neutralino-nucleon cross sections.
We notice that for nuclear targets with spin the spin-dependent interaction may
determine the lower bound for the direct detection rate when the cross section
of the scalar interaction drops below about $10^{-12} $pb.

</DOC>
<DOC>
<DOCNO> 67754 </DOCNO>
Gluon Pair Production From Space-Time Dependent Chromofield


  We compute the probabilty for the processes A -> q \bar{q}, gg via vacuum
polarization in the presence of a classical space-time dependent non-abelian
field A by applying the background field method of QCD. The processes we
consider are leading order in gA and are simillar to A -> e^+e^- in QED. Gluons
are treated like a matter field and gauge transformations of the quantum
gluonic field are different from those of the classical chromofield. To obtain
the correct physical polarization of gluons we deduct the corresponding ghost
contributions. We find that the expression for the probability of the leading
order process A -> gg is transverse with respect to the momentum of the field.
We observe that the contributions from higher order processes to gluon pair
production need to be added to the this leading order process. Our result
presented here is a part of the expression for the total probability for gluon
pair production from a space-time dependent chromfield. The result for q
\bar{q} pair production is similar to that of the e^+e^- pair production in
QED. Quark and gluon production from a space-time dependent chromofield will
play an important role in the study of the production and equilibration of the
quark-gluon plasma in ultra relativistic heavy-ion collisions.

</DOC>
<DOC>
<DOCNO> 71472 </DOCNO>
New meson mass relation and lowest pseudoscalar glueball mass


  A new meson mass relation for meson nonet is given after considering mixing
with glueball. The mixing between pseudoscalar mesons and pseudoscalar glueball
will decrease the mass of glueball by about 500 Mev. So, according to the
predicted mass of the pure pseudoscalar glueball given by lattice calculation
and effective Hamiltonian, the expected mass of mixed pseudoscalar glueball is
about 1.7 Gev. This result is helpful for experimemtal search for the mixed
Isoscalar pseudoscalar glueball.

</DOC>
<DOC>
<DOCNO> 8427 </DOCNO>
Regularities in football goal distributions


  Besides of complexities concerning to football championships, it is
identified some regularities in them. These regularities refer to goal
distributions by goal-players and by games. In particular, the goal
distribution by goal-players it well adjusted by the Zipf-Mandelbrot law,
suggesting a conection with an anomalous decay.

</DOC>
<DOC>
<DOCNO> 72084 </DOCNO>
Net-baryon scaling near the QCD critical point


  The net-baryon density at midrapidity is proposed as an order parameter in
the search for the QCD critical point in heavy ion collisions. As a function of
the initial energy and the total number of participants, this quantity obeys a
scaling law, dictated by the critical exponents of the appropriate universality
class. The corresponding scaling variable specifies the proximity of a given
experiment to the critical point. Within this framework, measurements at the
SPS are discussed and predictions for RHIC and LHC are extracted.

</DOC>
<DOC>
<DOCNO> 84612 </DOCNO>
Relativity of spatial scale and of the Hubble flow: The logical


  Formalising the logical dependence of physical quantities on material
referents of scale, I show that both Hubble's law and the cosmological constant
are in fact exactly replicable by a spatial contraction of referents locally on
earth, and that the Pioneer anomaly is irrefutable indication that this is the
case. The formalism literally embodies Feynman's ``hot-plate'' model,
predictably yielding a logical derivation of the relativity postulates, and
importantly, suffices to demonstrate the inherent logical consistency of
general relativity and quantum mechanics, whose foundations I have shown
separately to be fundamentally computational. I further show that the spatial
contraction of our referents also accounts for considerable planetary and
geological data inexplicable in the standard model, and predicts that the
Hubble flow appears differently or is altogether absent from platforms in deep
space, depending on the local physics.

</DOC>
<DOC>
<DOCNO> 11830 </DOCNO>
Harmony in the Small-World


  The Small-World phenomenon, popularly known as six degrees of separation, has
been mathematically formalized by Watts and Strogatz in a study of the
topological properties of a network. Small-worlds networks are defined in terms
of two quantities: they have a high clustering coefficient C like regular
lattices and a short characteristic path length L typical of random networks.
Physical distances are of fundamental importance in the applications to real
cases, nevertheless this basic ingredient is missing in the original
formulation. Here we introduce a new concept, the connectivity length D, that
gives harmony to the whole theory. D can be evaluated on a global and on a
local scale and plays in turn the role of L and 1/C. Moreover it can be
computed for any metrical network and not only for the topological cases. D has
a precise meaning in term of information propagation and describes in an
unified way both the structural and the dynamical aspects of a network:
small-worlds are defined by a small global and local D, i.e. by a high
efficiency in propagating information both on a local and on a global scale.
The neural system of the nematode C. elegans, the collaboration graph of film
actors, and the oldest U.S. subway system, can now be studied also as metrical
networks and are shown to be small-worlds.

</DOC>
<DOC>
<DOCNO> 102847 </DOCNO>
Stable Spin Maps, Gromov-Witten Invariants, and Quantum Cohomology


  We introduce the stack of r-spin maps. These are stable maps into a variety V
from n-pointed algebraic curves of genus g, with the additional data of an
r-spin structure on the curve.
  We prove that this stack is a Deligne-Mumford stack, and we define analogs of
the Gromov-Witten classes associated to these spaces. We show that these
classes yield a cohomological field theory (CohFT) that is the tensor product
of the CohFT associated to the usual Gromov-Witten invariants of V and the
r-spin CohFT. When r=2, our construction gives the usual Gromov-Witten
invariants of V.
  Restricting to genus zero, we obtain the notion of an r-spin quantum
cohomology of V, whose Frobenius structure is isomorphic to the tensor product
of the Frobenius manifolds corresponding to the quantum cohomology of V and the
r-th Gelfand-Dickey hierarchy (or, equivalently, the A_{r-1} singularity). We
also prove a generalization of the descent property which, in particular,
explains the appearance of the psi-classes in the definition of gravitational
descendants. Finally, we compute the small phase space potential function when
r=3 and V=CP^1.

</DOC>
<DOC>
<DOCNO> 101518 </DOCNO>
Number theory casting a look at the mirror


  In this work, we give a purely analytic introduction to the phenomenon of
mirror symmetry for quintic threefolds via classical hypergeometric functions
and differential equations for them. Starting with a modular map and recent
transcendence results for its values, we regard a mirror map $z(q)$ as a
concept generalizing the modular one. We give an alternative approach
demonstrating the existence of non-linear differential equations for the mirror
map, and exploit both an elegant construction of Klemm-Lian-Roan-Yau and the Ax
theorem to prove that the Yukawa coupling $K(q)$ does not satisfy any algebraic
differential equation of order less than 7 with coefficients from
$\mathbb{C}(q)$.

</DOC>
<DOC>
<DOCNO> 70714 </DOCNO>
Why the f(0)(980) is mostly ssbar


  We exploit the W-emission process to study the measured weak decay of the
D(s,+)(1.9686) meson into f(0)(980) and a positively charged pion. We conclude
that the scalar f(0)(980) meson contains mostly strange-antistrange flavors,
which is supported by different model studies.

</DOC>
<DOC>
<DOCNO> 11434 </DOCNO>
Wetting of a symmetrical binary fluid mixture on a wall


  We study the wetting behaviour of a symmetrical binary fluid below the
demixing temperature at a non-selective attractive wall. Although it demixes in
the bulk, a sufficiently thin liquid film remains mixed. On approaching
liquid/vapour coexistence, however, the thickness of the liquid film increases
and it may demix and then wet the substrate. We show that the wetting
properties are determined by an interplay of the two length scales related to
the density and the composition fluctuations. The problem is analysed within
the framework of a generic two component Ginzburg-Landau functional
(appropriate for systems with short-ranged interactions). This functional is
minimized both numerically and analytically within a piecewise parabolic
potential approximation. A number of novel surface transitions are found,
including first order demixing and prewetting, continuous demixing, a
tricritical point connecting the two regimes, or a critical end point beyond
which the prewetting line separates a strongly and a weakly demixed film. Our
results are supported by detailed Monte Carlo simulations of a symmetrical
binary Lennard-Jones fluid at an attractive wall.

</DOC>
<DOC>
<DOCNO> 72093 </DOCNO>
Hadronic collisions: physics, models and event generators used for


  Most hadronic event generators which can be used for simulating hadronic and
nuclear collisions up to the highest energies are quite similar in their
construction and in the underlying theoretical concepts. At energies, where
data from accelerator and collider experiments are available the models agree
rather well with each other and with the most important features of the data.
As soon as we compare the extrapolations of the models at higher energy we find
in spite of the similarities in the underlying theoretical concepts quite often
striking differences between the predictions of the models.

</DOC>
<DOC>
<DOCNO> 83134 </DOCNO>
Implementing Integrity Constraints in an Existing Belief Revision System


  SNePS is a mature knowledge representation, reasoning, and acting system that
has long contained a belief revision subsystem, called SNeBR. SNeBR is
triggered when an explicit contradiction is introduced into the SNePS belief
space, either because of a user's new assertion, or because of a user's query.
SNeBR then makes the user decide what belief to remove from the belief space in
order to restore consistency, although it provides information to help the user
in making that decision. We have recently added automatic belief revision to
SNeBR, by which, under certain circumstances, SNeBR decides by itself which
belief to remove, and then informs the user of the decision and its
consequences. We have used the well-known belief revision integrity constraints
as a guide in designing automatic belief revision, taking into account,
however, that SNePS's belief space is not deductively closed, and that it would
be infeasible to form the deductive closure in order to decide what belief to
remove. This paper briefly describes SNeBR both before and after this revision,
discusses how we adapted the integrity constraints for this purpose, and gives
an example of the new SNeBR in action.

</DOC>
<DOC>
<DOCNO> 9253 </DOCNO>
Diversity of discrete breathers observed in a Josephson ladder


  We generate and observe discrete rotobreathers in Josephson junction ladders
with open boundaries. Rotobreathers are localized excitations that persist
under the action of a spatially uniform force. We find a rich variety of stable
dynamic states including pure symmetric, pure asymmetric, and mixed states. The
parameter range where the discrete breathers are observed in our experiment is
limited by retrapping due to dissipation.

</DOC>
<DOC>
<DOCNO> 100852 </DOCNO>
Noncommutative Differential Geometry and Twisting of Quantum Groups


  We outline the recent classification of differential structures for all main
classes of quantum groups. We also outline the algebraic notion of `quantum
manifold' and `quantum Riemannian manifold' based on quantum group principal
bundles, a formulation that works over general unital algebras.

</DOC>
<DOC>
<DOCNO> 14000 </DOCNO>
Nonlinear absorption of surface acoustic waves by composite fermions


  Absorption of surface acoustic waves by a two-dimensional electron gas in a
perpendicular magnetic field is considered. The structure of such system at the
filling factor $\nu$ close to 1/2 can be understood as a gas of {\em composite
fermions}. It is shown that the absorption at $\nu =1/2 $ can be strongly
nonlinear, while small deviation form 1/2 will restore the linear absorption.
Study of nonlinear absorption allows one to determine the force acting upon the
composite fermions from the acoustic wave at turning points of their
trajectories.

</DOC>
<DOC>
<DOCNO> 71155 </DOCNO>
Leptogenesis: Neutrinos and New Lepton Flavor Violation at the Tev


  Leptogenesis, i.e. the creation of a lepton asymmetry in the early Universe,
may occur through the decay of heavy singlet (right-handed) neutrinos. If we
require it not to be erased by physics beyond the Standard Model at the TeV
energy scale, then only 2 candidates are possible if they are subgroups of
$E_6$. These 2 solutions happen to be also the only ones within 1$\sigma$ of
the atomic parity violation data and the invisible $Z$ width. Lepton flavor
violation is predicted in one model, as well as in another unrelated model of
neutrino masses where the observable decay of a doubly charged scalar would
determine the relative magnitude of each element of the neutrino mass matrix.

</DOC>
<DOC>
<DOCNO> 10526 </DOCNO>
Light scattering spectra of supercooled molecular liquids


  The light scattering spectra of molecular liquids are derived within a
generalized hydrodynamics. The wave vector and scattering angle dependences are
given in the most general case and the change of the spectral features from
liquid to solidlike is discussed without phenomenological model assumptions for
(general) dielectric systems without long-ranged order. Exact microscopic
expressions are derived for the frequency-dependent transport kernels,
generalized thermodynamic derivatives and the background spectra.

</DOC>
<DOC>
<DOCNO> 152076 </DOCNO>
Instantons, Compactification and S-duality in N=4 SUSY Yang-Mills Theory


  We study N=4 supersymmetric Yang-Mills (SYM) theory with gauge group SU(2)
compactified to three dimensions on a circle of circumference beta. The eight
fermion terms in the effective action on the Coulomb branch are determined
exactly, for all beta, assuming the existence of an interacting Spin(8)
invariant fixed point at the origin. The resulting formulae are manifestly
invariant under the SL(2,Z) duality of four dimensional N=4 SYM and lead to
interesting quantitative predictions for instanton effects in gauge theory and
in Type II string theory.

</DOC>
<DOC>
<DOCNO> 151991 </DOCNO>
TASI Lectures: Introduction to the AdS/CFT Correspondence


  This is an introductory review of the AdS/CFT correspondence and of the ideas
that led to its formulation. We show how comparison of stacks of D3-branes with
corresponding supergravity solutions leads to dualities between conformal large
$N$ gauge theories in 4 dimensions and string backgrounds of the form
$AdS_5\times X_5$ where $X_5$ is an Einstein manifold. The gauge invariant
chiral operators of the field theory are in one-to-one correspondence with the
supergravity modes, and their correlation functions at strong `t Hooft coupling
are determined by the dependence of the supergravity action on AdS boundary
conditions. The simplest case is when $X_5$ is a 5-sphere and the dual gauge
theory is the ${\cal N}=4$ supersymmetric SU(N) Yang-Mills theory. We also
discuss D3-branes on the conifold corresponding to $X_5$ being a coset space
$T^{1,1}=(SU(2)\times SU(2))/U(1)$. This background is dual to a certain ${\cal
N}=1$ superconformal field theory with gauge group $SU(N)\times SU(N)$.

</DOC>
<DOC>
<DOCNO> 80897 </DOCNO>
A numerical study of Goldstone-mode effects and scaling functions of the


  We investigate numerically the three-dimensional O(2) model on 8^3-160^3
lattices as a function of the magnetic field H. In the low-temperature phase we
verify the H-dependence of the magnetization M induced by the Goldstone modes
and determine M in the thermodynamic limit on the coexistence line both by
extrapolation and by chiral perturbation theory. We compute two critical
amplitudes from the scaling behaviours on the coexistence line and on the
critical line. In both cases we find negative corrections to scaling. With
additional high temperature data we calculate the scaling function and show
that it has a smaller slope than that of the O(4) model. For future tests of
QCD lattice data we study as well finite-size-scaling functions.

</DOC>
<DOC>
<DOCNO> 9705 </DOCNO>
Exact Solution of a Repulsive Fermi Model With Enhanced Superconducting


  We present the exact solution of a model of interacting fermions in any
dimension with a pure repulsive interaction projecting out a given Cooper
channel. The solution rests upon the infinite ranged character of the
interaction in real space, leading to a functional integral that is dominated
by a Gaussian term. The solution produces strong superconducting enhancements
and quasi long ranged order in a channel that is not present in the Hamiltonian
explicitly, but of the form given by arguments from order by projection.

</DOC>
<DOC>
<DOCNO> 68844 </DOCNO>
Production of CP-even and CP-odd Higgs bosons at Muon colliders


  In the $s$-channel Higgs-boson-exchange processes, the interference between
the amplitudes for CP-even and CP-odd Higgs bosons is sizable, if the
helicities of initial and final particles are properly fixed and if the mass
difference between these bosons is not much larger than their decay widths. We
discuss this interference effect in the process $\mu^+ \mu^-$ $\to t\bar{t}$.
Examining the effects gives us information on CP-parity for Higgs bosons and on
the sign of a product of the coupling constants for $H\mu^-\mu^+$, $Ht\bar{t}$,
$A\mu^-\mu^+$ and $At\bar{t}$ vertices. The feasibility of observing the
interference effect in future muon colliders is evaluated in the framework of
the minimal supersymmetric extension of the standard model as an example.

</DOC>
<DOC>
<DOCNO> 152189 </DOCNO>
Classical Integrability of Non Abelian Affine Toda Models


  A class of non abelian affine Toda models is constructed in terms of the
axial and vector gauged WZW model. It is shown that the multivacua structure of
the potential together with non abelian nature of the zero grade subalgebra
allows soliton solutions with non trivial electric and topological charges.
Their zero curvature representation and the classical $r$-matrix are also
constructed in order to prove their classical integrability.

</DOC>
<DOC>
<DOCNO> 40593 </DOCNO>
Testing the Universality of Fragmentation Functions


  Using fragmentation functions for charged pions, charged kaons, and
(anti)protons recently extracted from experimental data of e^+e^- annihilation
at the Z-boson resonance and at centre-of-mass energy root(s) = 29 GeV, we
perform a global study of inclusive charged-hadron production in p anti-p,
gamma p, and gamma gamma collisions at next-to-leading order in the parton
model of quantum chromodynamics. Comparisons of our results with p anti-p data
from CERN S p anti-p S and the Fermilab Tevatron, gamma p data from DESY HERA,
and gamma gamma data from CERN LEP2 allow us to test the universality of the
fragmentation functions predicted by the factorization theorem. Furthermore, we
perform comparisons with (e^+e^-)-annihilation data from LEP2 so as to test the
scaling violations predicted by the Altarelli-Parisi evolution equations.

</DOC>
<DOC>
<DOCNO> 10658 </DOCNO>
Quantum interference and Coulomb interaction in arrays of tunnel


  We study the electronic properties of an array of small metallic grains
connected by tunnel junctions. Such an array serves as a model for a granular
metal. Previous theoretical studies of junction arrays were based on models of
quantum dissipation which did not take into account the diffusive motion of
electrons within the grains. We demonstrate that these models break down at
sufficiently low temperatures: for a correct description of the screening
properties of a granular metal at low energies the diffusive nature of the
electronic motion within the grains is crucial. We present both a diagrammatic
and a functional integral approach to analyse the properties of junction
arrays. In particular, a new effective action is obtained which enables us to
describe the array at arbitrary temperature. In the low temperature limit, our
theory yields the correct, dynamically screened Coulomb interaction of a normal
metal, whereas at high temperatures the standard description in terms of
quantum dissipation is recovered.

</DOC>
<DOC>
<DOCNO> 119703 </DOCNO>
The detection of spiral arm modulation in the stellar disk of an


  Two dimensional Fourier spectra of near-infrared images of galaxies provide a
powerful diagnostic tool for the detection of spiral arm modulation in stellar
disks. Spiral arm modulation may be understood in terms of interference
patterns of outgoing and incoming density wave packets or modes. The brightness
along a spiral arm will be increased where two wave crests meet and
constructively interfere, but will be decreased where a wave crest and a wave
trough destructively interfere. Spiral arm modulation has hitherto only been
detected in grand design spirals (such as Messier 81). Spiral arm amplitude
variations have the potential to become a powerful constraint for the study of
galactic dynamics. We illustrate our method in two galaxies: NGC 4062 and NGC
5248. In both cases, we have detected trailing and leading m=2 waves with
similar pitch angles. This suggests that the amplification mechanism is the
WASER type II. In this mechanism, the bulge region reflects (rather than
refracts) incoming waves with no change of pitch angle, but only a change of
their sense of winding. The ratio between the amplitudes of the leading and the
trailing waves is about 0.5 in both cases, wherein the higher amplitude is
consistently assigned to the trailing (as opposed to leading) mode. The results
are particularly significant because NGC 5248 is an optically grand design
galaxy, whereas NGC 4062 is optically flocculent. NGC 4062 represents the very
first detection of spiral arm modulation in the stellar disk of an optically
flocculent galaxy.

</DOC>
<DOC>
<DOCNO> 102564 </DOCNO>
Invariance of plurigenera of varieties with nonngative Kodaira


  We prove the invariance of plurigenera under smooth projective deformations
of varieties with nonnegative Kodaira dimensions.

</DOC>
<DOC>
<DOCNO> 13892 </DOCNO>
Rectification of displacement currents in an adiabatic electron pump


  Rectification of ac displacement currents generated by periodic variation of
two independent gate voltages of a quantum dot can lead to a dc voltage linear
in the frequency. The presence of this rectified displacement current could
account for the magnetic field symmetry observed in a recent measurement on an
adiabatic quantum electron pump by Switkes et al. [Science 283, 1905 (1999)].

</DOC>
<DOC>
<DOCNO> 121626 </DOCNO>
The Kuiper Belt and Olbers Paradox


  We investigate the constraints that Olbers Paradox, applied to the Zodiacal
Background as measured from space, sets on outer solar system objects. If
extended to very faint limits, R = 40--50 mag, the steep optical luminosity
function (LF) of Kuiper Belt objects (KBOs) at R less than 26 mag implies an
infinitely bright night sky. Small KBOs with radii of 1 mm to 1 km must have a
size distribution n(r) proportional to r^{-a}, with a = 3.5 or smaller to
satisfy the known limits on the sky-surface brightness at optical and
far-infrared wavelengths. Improved limits on the measured KBO surface
brightness can yield direct estimates of the albedo, temperature, and size
distribution for small KBOs in the outer solar system.

</DOC>
<DOC>
<DOCNO> 178948 </DOCNO>
The Original Mixed Symmetry States - $6^{+}_{1}$ and $6^{+}_{2}$ in


  The $6^{+}_{1}$ and $6^{+}_{2}$ in $^{48}$Ti form a nearly degenerate
doublet. In a single j shell calculation with the matrix elements from
experiment the $6^{+}_{1}$ changes sign under the interchange of protons and
neutron holes (odd signature) while the $6_{2}^{+}$ does not (even signature).
As a consequence the calculated B(E2) $6_{1}^{+}\to 4_{1}^{+}$ is much stronger
than the $6_{2}^{+}\to 4_{1}^{+}$ and the Gamow-Teller matrix element to the
$6_{2}^{+}$ state vanishes. When using some popular interaction e.g. FPD6 in
single j shell the ordering of the even signature and odd signature states gets
reversed, so that the Gamow-Teller matrix element to the $6^{+}_{1}$ state
vanishes and the $6_{2}^{+}\to 4_{1}^{+}$ E2 transition is the strong one. When
configuration mixing is introduced, the E2 transition $6_{2}^{+}\to 4_{1}^{+}$
persists in being large. However the Gamow-Teller strengths reverse, with the
large matrix element to the $6_{1}^{+}$ state in agreement with experiment.
Static properties $\mu$ and Q for the two $6^{+}$ states are also considered.
The experimental B(E2)'s from the $6^{+}$ states to the $4_{1}^{+}$ state are
not well known.

</DOC>
<DOC>
<DOCNO> 14154 </DOCNO>
Exotic Superconducting Phase in CeCu2Si2 Close to Antiferromagnetism : A


  We report Cu nuclear-quadrupole-resonance results under pressure on a
homogeneous CeCu2Si2 (Tc = 0.65 K) that revealed critical magnetic fluctuations
at the border to an antiferromagnetic phase. This exotic superconducting phase
evolves into the typical heavy-fermion superconducting phase at minute
pressures exceeding Pc ~ 0.2 GPa. The nuclear spin-lattice relaxation data in a
pressure range 0.85 - 2.58 GPa are shown to be accountable by the SCR theory
based on the nearly antiferromagnetic Fermi-liquid model. In 0 < P < Pc ~ 0.2
GPa, by contrast, we conclude that the exotic superconducting phase manifests
itself under the unconventional normal state where antiferromagnetic waves
propagate over a long range without any trace of antiferromagnetic order and
thereby the heavy-fermion state breaks up.

</DOC>
<DOC>
<DOCNO> 12359 </DOCNO>
Shot-noise suppression in Schottky barrier diodes


  We give a theoretical interpretation of the noise properties of Schottky
barrier diodes based on the role played by the long range Coulomb interaction.
We show that at low bias Schottky diodes display shot noise because the
presence of the depletion layer makes negligible the effects of the Coulomb
interaction on the current fluctuations. When the device passes from barrier to
flat band conditions, the Coulomb interaction becomes active, thus introducing
correlation between different current fluctuations. Therefore, the cross-over
between shot and thermal noise represents the suppression due to long range
Coulomb interaction of the otherwise full shot-noise. Similar ideas can be used
to interpret the noise properties of others semiconductor devices.

</DOC>
<DOC>
<DOCNO> 69829 </DOCNO>
$B\to \pi \pi, K \pi$ Decays in QCD Improved Factorization Approach


  Motivated by recent measurements, we investigate $B\to \pi \pi, K \pi$ decay
modes in the framework of QCD improved factorization, which was recently
proposed by Beneke $et al$. We find that all the measured branching ratios are
well accommodated in the reasonable parameter space except for $B\to K^0 \pi^0
$. We also discuss in detail the strong penguin contributions and the ${\cal
O}(\alpha_s)$ corrections to the chirally enhanced terms. We find that the weak
phase $\gamma$ lies in the region $120^{\circ}<\gamma<240^{\circ}$, which is
mainly constrained by $B\to \pi^- \pi^+ $.

</DOC>
<DOC>
<DOCNO> 13261 </DOCNO>
Corrugation of Roads


  We present a one dimensional model for the development of corrugations in
roads subjected to compressive forces from a flux of cars. The cars are modeled
as damped harmonic oscillators translating with constant horizontal velocity
across the surface, and the road surface is subject to diffusive relaxation. We
derive dimensionless coupled equations of motion for the positions of the cars
and the road surface H(x,t), which contain two phenomenological variables: an
effective diffusion constant Delta(H) that characterizes the relaxation of the
road surface, and a function alpha(H) that characterizes the plasticity or
erodibility of the road bed. Linear stability analysis shows that corrugations
grow if the speed of the cars exceeds a critical value, which decreases if the
flux of cars is increased. Modifying the model to enforce the simple fact that
the normal force exerted by the road can never be negative seems to lead to
restabilized, quasi-steady road shapes, in which the corrugation amplitude and
phase velocity remain fixed.

</DOC>
<DOC>
<DOCNO> 8123 </DOCNO>
Conductivity of a clean one-dimensional wire


  We study the low-temperature low-frequency conductivity sigma of an
interacting one dimensional electron system in the presence of a periodic
potential. The conductivity is strongly influenced by conservation laws, which,
we argue, need be violated by at least two non-commuting Umklapp processes to
render sigma finite. The resulting dynamics of the slow modes is studied within
a memory matrix approach, and we find exponential increase as the temperature
is lowered, sigma = (Delta n)^2 e^{T_0/(N T)} close to commensurate filling
M/N, Delta n=n-M/N << 1, and sigma = e^{(T'_0/T)^{2/3}} elsewhere.

</DOC>
<DOC>
<DOCNO> 100729 </DOCNO>
Finite Difference Approximation of Free Discontinuity Problems


  We approximate functionals depending on the gradient of $u$ and on the
behaviour of $u$ near the discontinuity points, by families of non-local
functionals where the gradient is replaced by finite differences. We prove
pointwise convergence, $\Gamma$-convergence, and a compactness result which
implies, in particular, the convergence of minima and minimizers.

</DOC>
<DOC>
<DOCNO> 178706 </DOCNO>
Partial wave contributions to the antikaon potential at finite momentum


  The momentum dependence of the antikaon optical potential in nuclear matter
is obtained from a microscopic and self-consistent calculation using the
meson-exchange J\"ulich $\bar{K}N$ interaction. Two self-consistent schemes are
discussed, which would lead to substantially different predictions for the
width of ${\bar K}$ nuclear bound states. The effect of higher partial waves of
the $\bar{K}N$ interaction, beyond the L=0 component, is studied and found to
have moderate but non-negligible effects on the ${\bar K}$ nuclear potential at
zero momentum. At momenta as large as 500 MeV/c, relevant in the analysis of
heavy-ion collisions, the higher partial partial waves modify the ${\bar K}$
optical potential by nearly a factor of two.

</DOC>
<DOC>
<DOCNO> 117365 </DOCNO>
Updated Information on the Local Group


  The present note updates the information published in my recent monograph on
\underline{The Galaxies of the Local Group}. Highlights include (1) the
addition of the newly discovered Cetus dwarf spheroidal as a certain member of
the Local Group, (2) an improved distance for SagDIG, which now places this
object very close to the edge of the Local Group zero-velocity surface, (3)
more information on the evolutionary histories of some individual Local Group
members, and (4) improved distance determinations to, and luminosities for, a
number of Local Group members. These data increase the number of certain (or
probable) Local Group members to 36. The spatial distribution of these galaxies
supports Hubble's claim that the Local Group ``is isolated in the general
field.'' Presently available evidence suggests that star formation continued
much longer in many dwarf spheroidals than it did in the main body of the
Galactic halo. It is suggested that ``young'' globular clusters, such as
Ruprecht 106, might have formed in now defunct dwarf spheroidals. Assuming
SagDIG, which is the most remote Local Group galaxy, to lie on, or just inside,
the zero-velocity surface of the Local Group yields a dynamical age \gtrsim
17.9 \pm 2.7 Gyr.

</DOC>
<DOC>
<DOCNO> 121335 </DOCNO>
WSRT and VLA Observations of the 6 cm and 2 cm lines of H2CO in the


  Absorption in the J{K-K+} = 2{11}-2{12} transition of formaldehyde at 2 cm
towards the ultracompact HII regions C1 and C2 of W 58 has been observed with
the VLA with an angular resolution of ~0.2'' and a velocity resolution of ~1
km/s. The high resolution continuum image of C1 (ON 3) shows a partial shell
which opens to the NE. Strong H2CO absorption is observed against W 58 C1. The
highest optical depth (tau > 2) occurs in the SW portion of C1 near the edge of
the shell, close to the continuum peak. The absorption is weaker towards the
nearby, more diffuse compact HII region C2, tau<~0.3. The H2CO velocity (-21.2
km/s) towards C1 is constant and agrees with the velocity of CO emission,
mainline OH masers, and the H76 alpha recombination line, but differs from the
velocity of the 1720 MHz OH maser emission (~-13 km/s). Observations of the
absorption in the J{K-K+} = 1{10}-1{11} transition of formaldehyde at 6 cm
towards W 58 C1 and C2 carried out earlier with the WSRT at lower resolution
(~4''x7'') show comparable optical depths and velocities to those observed at 2
cm. Based on the mean optical depth profiles at 6 cm and 2 cm, the volume
density of molecular hydrogen n(H2) and the formaldehyde column density N(H2CO)
were determined. The n(H2) is ~6E4 /cm**3 towards C1. N(H2CO) for C1 is ~8E14
/cm**2 while that towards C2 is ~8E13 /cm**2.

</DOC>
<DOC>
<DOCNO> 152635 </DOCNO>
Vaccum Polarization for a Massless Scalar Field in the Global Monopole


  In this paper we calculate the effects produced by temperature in the
renormalized vaccum expectation value of the square of the massless scalar
field in the pointlike global monopole spacetime. In order to develop this
calculation, we had to construct the Euclidean thermal Green function
associated with this field in this background. We also calculate the
high-temperature limit for the thermal average of the zero-zero component of
the energy-momentum tensor.

</DOC>
<DOC>
<DOCNO> 7739 </DOCNO>
Stretching necklaces


  Polyelectrolytes in poor solvents show a necklace structure where collapsed
polymer pearls are linked to stretched strings. In the present paper the
elasticity of such chains is studied in detail. Different deformation regimes
are addressed. The first is the continuous regime, where many pearls are
present. A continuous force extension relation ship is calculated. The main
contribution comes from the tension balance and the electrostatic repulsion of
consecutive pearls. The main correction term stems from the finite size of the
pearls, which monitors their surface energy. For a finite amount of pearls
discontinuous stretching is predicted. Finally counterion effects are discussed
qualitatively.

</DOC>
<DOC>
<DOCNO> 71150 </DOCNO>
Relaxation Near the Critical Point


  I present an analysis of the relaxation rate for long-wavelength fluctuations
of the order parameter in an O(N) scalar theory near the critical point. Our
motivation is to model the non-equilibrium dynamics of critical fluctuations
near the chiral phase transition in QCD. In the next-to-leading order in the
large $N$ expansion we find a critical slowing down regime, i.e. an increasing
of the relaxation time of long wavelengths fluctuations. This result suggests,
for near critical systems, relevant deviations from thermal equilibrium for the
distribution functions of low-energy particles and could have important
phenomenological consequences in Heavy Ions Collision and in the Early Universe
Cosmology.

</DOC>
<DOC>
<DOCNO> 70789 </DOCNO>
B -> X_s gamma in supersymmetry: large contributions beyond the leading


  We discuss possible large contributions to B -> X_s gamma, which can occur at
the next-to-leading order in supersymmetric models. They can originate from
terms enhanced by tan(beta) factors, when the ratio between the two Higgs
vacuum expectation values is large, or by logarithm of M_{susy}/M_W, when the
supersymmetric particles are considerably heavier than the W boson. We give
compact formulae which include all potentially large higher-order
contributions. We find that tan(beta) terms at the next-to-leading order do not
only appear from the Hall-Rattazzi-Sarid effect (the modified relation between
the bottom mass and Yukawa coupling), but also from an analogous effect in the
top-quark Yukawa coupling. Finally, we show how next-to-leading order
corrections, in the large tan(beta) region, can significantly reduce the limit
on the charged-Higgs mass, even if supersymmetric particles are very heavy.

</DOC>
<DOC>
<DOCNO> 9742 </DOCNO>
What is a physical measure of spatial inhomogeneity comparable to the


  A linear transformation f(S) of configurational entropy with length scale
dependent coefficients as a measure of spatial inhomogeneity is considered.
When a final pattern is formed with periodically repeated initial arrangement
of point objects the value of the measure is conserved. This property allows
for computation of the measure at every length scale. Its remarkable
sensitivity to the deviation (per cell) from a possible maximally uniform
object distribution for the length scale considered is comparable to behaviour
of strictly mathematical measure h introduced by Garncarek et al. in [2].
Computer generated object distributions reveal a correlation between the two
measures at a given length scale for all configurations as well as at all
length scales for a given configuration. Some examples of complementary
behaviour of the two measures are indicated.

</DOC>
<DOC>
<DOCNO> 101119 </DOCNO>
On q-deformed quantum stochastic calculus


  In this paper we investigate a quantum stochastic calculus build of creation,
annihilation and number of particles operators which fulfill some deformed
commutation relations.
  Namely, we introduce a deformation of a number of particles operator which
has simple commutation relations with well known q-deformed creation and
annihilation operators. Since all operators considered in this theory are
bounded we do not deal with some difficulties of a non deformed theory of
Hudson and Parthasarathy. We define stochastic integrals and estimate them in
the operator norm. We prove Ito's formula as well.

</DOC>
<DOC>
<DOCNO> 68161 </DOCNO>
Qualitative Signals of New Physics in B-Bbar Mixing


  It is expected that, within the next three years, the determination of the
CKM matrix elements with the least theoretical uncertainty will arise from the
measurements of CP violation in B_d --> J/\psi K_S decays and from Bs-Bsbar
mixing. If there is significant new physics in Bs-Bsbar mixing, then those
experiments will not yield the correct values for the CKM matrix elements. As a
result, a qualitative signal of new physics may appear in the CP violation of
decays like B_d --> pi+ pi-.

</DOC>
<DOC>
<DOCNO> 118522 </DOCNO>
Bound systems in an expanding universe


  The Schwarzchild solution insertion in an expanding universe, the so-called
"Swiss cheese model," is shown to possess a very unphysical property.
Specifically, in this model some trajectories are discontinuous functions of
their initial conditions. An alternate metric is proposed as a remedy. It goes
smoothly between the Schwarzchild exterior solution and the Friedmann-Lemaitre,
expanding universe metric. It is further shown that the effects of the
expansion on planetary motions in the solar system are too small to be
currently observed for this alternate metric.

</DOC>
<DOC>
<DOCNO> 9841 </DOCNO>
Optical properties and electronic structure of Ca-doped alpha'-NaV2O5


  The dielectric function of alpha'-Na(1-x)Ca(x)V2O5 (0 < x < 20%) was measured
for the a and b axes in the photon energy range 0.8-4.5 eV at room temperature.
By varying the Ca-concentration we control the relative abundancy of V4+ and
V5+. We observe that the intensity of the main optical absorption peak at 1 eV
is proportional to the number of V5+ ions. This rules out the interpretation as
a V4+ d-d excitation, and it establishes that this is the on-rung
bonding-antibonding transition.

</DOC>
<DOC>
<DOCNO> 178914 </DOCNO>
Nucleonic resonance excitations with linearly polarized photon in


  In this work, an improved quark model approach to the $\omega$ meson
photo-production with an effective Lagrangian is presented. The {\it t}-channel
{\it natural}-parity exchange is taken into account through the Pomeron
exchange, while the {\it unnatural}-parity exchange is described by the $\pi^0$
exchange. With a very limited number of parameters, the available experimental
data in the low energy regime can be consistently accounted for. We find that
the beam polarization observables show sensitivities to some {\it s}-channel
individual resonances in the $SU(6)\otimes O(3)$ quark model symmetry limit.
Especially, the two resonances $P_{13}(1720)$ and $F_{15}(1680)$, which belong
to the representation $[{\bf 56, ^2 8}, 2, 2, J]$, have dominant contributions
over other excited states. Concerning the essential motivation of searching for
"missing resonances" in meson photo-production, this approach provides a
feasible framework, on which systematic investigations can be done.

</DOC>
<DOC>
<DOCNO> 116672 </DOCNO>
A mechanical model that exhibits a gravitational critical radius


  Circular orbits of a particle sliding on a frictionless surface of revolution
about a vertical axis are unstable below a critical radius if the curvature of
the surface satisfies a specified condition. This behavior can be realized in a
mechanical model, which give a glimpse of the greater complexity of particle
orbits in curved rather than flat spacetime.

</DOC>
<DOC>
<DOCNO> 69680 </DOCNO>
Evolution of truncated moments of singlet parton distributions


  We define truncated Mellin moments of parton distributions by restricting the
integration range over the Bjorken variable to the experimentally accessible
subset x_0 < x < 1 of the allowed kinematic range 0 < x < 1. We derive the
evolution equations satisfied by truncated moments in the general (singlet)
case in terms of an infinite triangular matrix of anomalous dimensions which
couple each truncated moment to all higher moments with orders differing by
integers. We show that the evolution of any moment can be determined to
arbitrarily good accuracy by truncating the system of coupled moments to a
sufficiently large but finite size, and show how the equations can be solved in
a way suitable for numerical applications. We discuss in detail the accuracy of
the method in view of applications to precision phenomenology.

</DOC>
<DOC>
<DOCNO> 9434 </DOCNO>
Magnetic Phase Transition of the Perovskite-type Ti Oxides


  Properties and mechanism of the magnetic phase transition of the
perovskite-type Ti oxides, which is driven by the Ti-O-Ti bond angle
distortion, are studied theoretically by using the effective spin and
pseudo-spin Hamiltonian with strong Coulomb repulsion. It is shown that the
A-type antiferromagnetic(AFM(A)) to ferromagnetic(FM) phase transition occurs
as the Ti-O-Ti bond angle is decreased. Through this phase transition, the
orbital state is hardly changed so that the spin-exchange coupling along the
$c$-axis changes nearly continuously from positive to negative and takes
approximately zero at the phase boundary. The resultant strong
two-dimensionality in the spin coupling causes a rapid suppression of the
critical temperature as is observed experimentally.

</DOC>
<DOC>
<DOCNO> 80912 </DOCNO>
Percolation and Critical Behaviour in SU(2) Gauge Theory


  The paramagnetic-ferromagnetic transition in the Ising model can be described
as percolation of suitably defined clusters. We have tried to extend such
picture to the confinement-deconfinement transition of SU(2) pure gauge theory,
which is in the same universality class of the Ising model. The cluster
definition is derived by approximating SU(2) by means of Ising-like effective
theories. The geometrical transition of such clusters turns out to describe
successfully the thermal counterpart for two different lattice regularizations
of (3+1)-d SU(2).

</DOC>
<DOC>
<DOCNO> 151173 </DOCNO>
(Anti-)Instantons and the Atiyah-Hitchin Manifold


  The Atiyah-Hitchin manifold arises in many different contexts, ranging from
its original occurrence as the moduli space of two SU(2) 't Hooft-Polyakov
monopoles in 3+1 dimensions, to supersymmetric backgrounds of string theory. In
all these settings, (super)symmetries require the metric to be hyperk\"ahler
and have an SO(3) transitive isometry, which in the four-dimensional case
essentially selects out the Atiyah-Hitchin manifold as the only such smooth
manifold with the correct topology at infinity. In this paper, we analyze the
exponentially small corrections to the asymptotic limit, and interpret them as
infinite series of instanton corrections in these various settings.
Unexpectedly, the relevant configurations turn out to be bound states of $n$
instantons and $\bar n$ anti-instantons, with $|n-\bar n|=0,1$ as required by
charge conservation. We propose that the semi-classical configurations relevant
for the higher monopole moduli space are Euclidean open branes stretched
between the monopoles.

</DOC>
<DOC>
<DOCNO> 99985 </DOCNO>
Limiting distributions for a polynuclear growth model with external


  The purpose of this paper is to investigate the limiting distribution
functions for a polynuclear growth model with two external sources, which was
considered by Pr\"ahofer and Spohn. Depending on the strength of the sources,
the limiting distribution functions are either the Tracy-Widom functions of
random matrix theory, or a new explicit function which has the special property
that its mean is zero. Moreover, we obtain transition functions between pairs
of the above distribution functions in suitably scaled limits. There are also
similar results for a discrete totally asymmetric exclusion process.

</DOC>
<DOC>
<DOCNO> 122042 </DOCNO>
Determination of the orbital parameters of binary pulsars


  We present a simple novel method for determining the orbital parameters of
binary pulsars. This method works with any sort of orbital sampling, no matter
how sparse, provided that information on the period derivatives is available
with each measurement of the rotational period of the pulsar, and it is
applicable to binary systems with nearly circular orbits. We use the technique
to precisely estimate the hitherto unknown orbital parameters of two binary
millisecond pulsars in the globular cluster 47 Tucanae, 47 Tuc S and T. The
method can also be used more generally to make first-order estimates of the
orbital parameters of binary systems using a minimal amount of data.

</DOC>
<DOC>
<DOCNO> 85280 </DOCNO>
Impossible solutions?


  We present n-dimensional vortex-ring-like and potential-like solutions with
unusual properties related to some elliptical differential equations with
compact sources. Solutions have almost 3- or 2-dimensional behaviour in the
spaces with arbitrary (large) odd and even dimensions, respectively.

</DOC>
<DOC>
<DOCNO> 12729 </DOCNO>
Convective Nonlinearity in Non-Newtonian Fluids


  In the limit of infinite yield time for stresses, the hydrodynamic equations
for viscoelastic, Non-Newtonian liquids such as polymer melts must reduce to
that for solids. This piece of information suffices to uniquely determine the
nonlinear convective derivative, an ongoing point of contention in the rheology
literature.

</DOC>
<DOC>
<DOCNO> 118625 </DOCNO>
Structure in the local Galactic ISM on scales down to 1 pc, from


  We discuss observations of the linearly polarized component of the diffuse
galactic radio background. These observations, with an angular resolution of
4', were made with the Westerbork Synthesis Radio Telescope (WSRT) in 5
frequency bands in the range 341-375 MHz. The linearly polarized intensity P
(with polarized brightness temperature going up to 10K) shows a `cloudy'
structure, with characteristic scales of 15'-30', which contains relatively
long, but very narrow `canals' (essentially unresolved) in which P is only a
small fraction of that in the neighbouring beams.
  These `canals' are generally seen in more than one frequency band, although
their appearance changes between bands. They are probably due to depolarization
within the synthesized beam, because the change in polarization angle across
the deepest `canals' is in general close to 90 degrees (or 270 etc.). These
very abrupt changes in polarization angle, which are seen only across the
`canals', seem to be accompanied by abrupt changes in the Rotation Measure
(RM), which may have the right magnitude to create the difference of close to
90 degrees in polarization angle, and thereby the `canals'.
  The structure in the polarization maps is most likely due to Faraday rotation
modulation of the probably smooth polarized radiation emitted in the halo of
our Galaxy by the fairly local ISM (up to 500 pc). Therefore, the abrupt
changes of RM across the `canals' provide evidence for very thin (about 1 pc),
and relatively long transition regions in the ISM, across which the RM changes
by as much as 100%. Such drastic RM changes may well be due primarily to abrupt
changes in the magnetic field.

</DOC>
<DOC>
<DOCNO> 83246 </DOCNO>
Using a Diathesis Model for Semantic Parsing


  This paper presents a semantic parsing approach for unrestricted texts.
Semantic parsing is one of the major bottlenecks of Natural Language
Understanding (NLU) systems and usually requires building expensive resources
not easily portable to other domains. Our approach obtains a case-role
analysis, in which the semantic roles of the verb are identified. In order to
cover all the possible syntactic realisations of a verb, our system combines
their argument structure with a set of general semantic labelled diatheses
models. Combining them, the system builds a set of syntactic-semantic patterns
with their own role-case representation. Once the patterns are build, we use an
approximate tree pattern-matching algorithm to identify the most reliable
pattern for a sentence. The pattern matching is performed between the
syntactic-semantic patterns and the feature-structure tree representing the
morphological, syntactical and semantic information of the analysed sentence.
For sentences assigned to the correct model, the semantic parsing system we are
presenting identifies correctly more than 73% of possible semantic case-roles.

</DOC>
<DOC>
<DOCNO> 84845 </DOCNO>
Non-Parallel Electric and Magnetic Fields in a Gravitational Background,


  The existence of an electromagnetic field with parallel electric and magnetic
field components in the presence of a gravitational field is considered. A
non-parallel solution is shown to exist. Next, we analyse the possibility of
finding stationary gravitational waves in nature. Finally, we construct a D=4
effective quantum gravity model. Tree-level unitarity is verified.

</DOC>
<DOC>
<DOCNO> 120063 </DOCNO>
The Dynamical Interstellar Medium: Insights from Numerical Models


  Numerical models of the dynamical interstellar medium show that interactions
between structures such as supernova remnants and superbubbles are more
important than the structures themselves in determining the behavior of the
ISM. I review the techniques and conclusions of recent global models, focussing
on what they tell us about the formation of star-forming giant molecular
clouds.

</DOC>
<DOC>
<DOCNO> 101502 </DOCNO>
Symmetry and specializability in continued fractions


  We study explicit continued fraction expansions for certain series. Some of
these expansions have symmetry that generalizes some remarkable examples
discovered independently by Kmosek and Shallit. Furthermore, we prove the
following theorem: Suppose f(x) is a polynomial with integer coefficients, and
consider the sum of 1/f^n(x) as n goes from 0 to infinity, where f^n denotes
the n-th iterate of f. This series has a continued fraction expansion over the
polynomials. The case when the partial quotients have integer coefficients is
particularly interesting, since then one can obtain simple continued fractions
when one substitutes integer values for x. In this case, the continued fraction
expansion is called specializable. We determine all polynomials f(x) such that
the sum of 1/f^n(x) has a specializable continued fraction: this holds iff f(x)
satisfies one of 14 congruences.

</DOC>
<DOC>
<DOCNO> 170223 </DOCNO>
Maximum efficiency of a linear-optical Bell-state analyzer


  In a photonic realization of qubits the implementation of quantum logic is
rather difficult due the extremely weak interaction on the few photon level. On
the other hand, in these systems interference is available to process the
quantum states. We formalize the use of interference by the definition of a
simple class of operations which include linear optical elements, auxiliary
states and conditional operations.
  We investigate an important subclass of these tools, namely linear optical
elements and auxiliary modes in the vacuum state. For this tools, we are able
to extend a previous quantitative result, a no-go theorem for perfect Bell
state analyzer on two qubits in polarization entanglement, by a quantitative
statement. We show, that within this subclass it is not possible to
discriminate unambiguously four equiprobable Bell states with a probability
higher than 50 %.

</DOC>
<DOC>
<DOCNO> 84484 </DOCNO>
On static mirrors interacting with an electromagnetic vacuum


  Withdrawn due to the absence of an important shear term in Eq. (6), which
cancels the other term.

</DOC>
<DOC>
<DOCNO> 40273 </DOCNO>
ZZ Cross Section Measurements


  Results on the cross section measurement of Z boson pair-production at LEP
are presented. The more general case of neutral-current four-fermion production
and the particular case of ZZ events enriched in b quarks are also discussed.
All the results agree with the Standard Model predictions.

</DOC>
<DOC>
<DOCNO> 12259 </DOCNO>
Exact solution of Riemann--Hilbert problem for a correlation function of


  A correlation function of the XY spin chain is studied at zero temperature.
This is called the Emptiness Formation Probability (EFP) and is expressed by
the Fredholm determinant in the thermodynamic limit. We formulate the
associated Riemann--Hilbert problem and solve it exactly. The EFP is shown to
decay in Gaussian.

</DOC>
<DOC>
<DOCNO> 40180 </DOCNO>
Fabrication Process of Rounded Damped Detuned Structure


  Following the successful design and fabrication of Damped Detuned Structures
(DDS), the JLC/NLC linear collider project advanced to Rounded Damped Detuned
Structures (RDDS) with curved cross section of the cavity shape for increased
shunt impedance. Various advanced techniques for fabricating RDDS1 disks
comparing to those for DDS were established to satisfy the dimension accuracy
of +-1 micron over the entire surface made by ultra-precision turning. These
disks were assembled with almost the same stacking and bonding jigs and
processes as those of DDS3 assembly. In consequence, the assembly showed little
disk-to-disk misalignment within 1 micron before and after the process. Though,
it had 200 micron smooth bowing, which was subsequently corrected as DDS3, and
flares at both ends.

</DOC>
<DOC>
<DOCNO> 121371 </DOCNO>
Diameters of delta Cephei and eta Aquilae Measured with the Navy


  We have measured the diameters of the Cepheid variables delta Cephei (18
nights) and eta Aquilae (11 nights) with the Navy Prototype Optical
Interferometer. The primary results of these observations are the mean angular
diameters <theta(LD)> of these Cepheids: 1.520 +/- 0.014 milliseconds of arc
(mas) for delta Cep and 1.69 +/- 0.04 mas for eta Aql. We also report
limb-darkened diameters for the check stars in this program: for beta Lac,
theta(LD) = 1.909 +/- 0.011 mas, and for 12 Aql, theta(LD) = 2.418 +/- 0.010
mas. When combined with radius estimates from period-radius relations in the
literature, the Cepheid angular diameters suggest distances slightly smaller
than, but still consistent with, the Hipparcos distances. Pulsations are weakly
detected at a level of about 1.5 sigma to 2 sigma for both Cepheids.

</DOC>
<DOC>
<DOCNO> 84551 </DOCNO>
Cataclysmic variables as sources of gravitational waves


  General Relativity predicts that binary systems of stars produce
gravitational waves of significant intensity. Here we are particularly
interested in the cataclysmic variable binaries (CVs). These systems emit low
frequency gravitational waves, $ f < 10^{-3} Hz$. We present here a catalog of
CVs and argue that part of them are capable of being detected by the Laser
Interferometer Space Antenna (LISA).

</DOC>
<DOC>
<DOCNO> 122373 </DOCNO>
On the Stability of Quasi-Equilibrium Self-Gravitating Configurations in


  The possibility that quasi-equilibrium self-gravitating galaxy-like
configurations exist in a tidal field is analyzed in this paper. More
specifically, we address the question of how to predict initial configurations
modeling galaxies that are able to survive environmental effects in a dense
environment for a Hubble time or so, provided thay dynamical friction is
neglected. The initial quasi-equilibrium configurations have been built up
taking into account the external tidal field produced by the halo. It modifies
the escape velocity field of the configuration, compared with isolated
configurations. The survival of the configurations as they orbit inside the
halos has been studied through N-body simulations. As a general result, it has
been found out that the bulk of the models is conserved along 12.5 Gyears of
evolution, and that the low rates of mass losses they experience are consistent
with those expected when the adiabatic protection hypothesis is at work. So,
solutions for galaxy configurations in tidal quasi-equilibrium have been found,
showing that tidal stripping in quiescent phases does not seem to be very
important, unless that the density of the galaxy environment at its formation
had been much lower than that of the galaxy environment at the point of its
orbit where the tidal perturbation is maximum. (Abridged)

</DOC>
<DOC>
<DOCNO> 152193 </DOCNO>
Fractional Spin through Quantum Affine Algebra $\hat A(n)$ and quantum


  Using the splitting of a $Q$-deformed boson, in the $Q \to q= e^{\frac{\rm
2\pi i}{\rm k}}$ limit, the fractional decomposition of the quantum affine
algebra $\hat A(n)$ and the quantum affine superalgebra $\hat A(n,m)$ are
found. This decomposition is based on the oscillator representation and can be
related to the fractional supersymmetry and k-fermionic spin. We establish also
the equivalence between the quantum affine algebra $\hat A(n)$ and the
classical one in the fermionic realization.

</DOC>
<DOC>
<DOCNO> 122180 </DOCNO>
XMM-Newton First-Light Observations of the Hickson Galaxy Group 16


  This paper presents the XMM-Newton first-light observations of the Hickson-16
compact group of galaxies. Groups are possibly the oldest large-scale
structures in the Universe, pre-dating clusters of galaxies, and are highly
evolved. This group of small galaxies, at a redshift of 0.0132 (or 80 Mpc) is
exceptional in the having the highest concentration of starburst or AGN
activity in the nearby Universe. So it is a veritable laboratory for the study
of the relationship between galaxy interactions and nuclear activity. Previous
optical emission line studies indicated a strong ionising continuum in the
galaxies, but its origin, whether from starbursts, or AGN, was unclear.
Combined imaging and spectroscopy with the EPIC X-ray CCDs unequivocally
reveals a heavily obscured AGN and a separately identified thermal (starburst)
plasma, in NGC 835, NGC 833 and NGC 839. NGC 838 shows only starburst thermal
emission. Starbursts and AGN can evidently coexist in members of this highly
evolved system of merged and merging galaxies, implying a high probability for
the formation of AGN as well as starbursts in post-merger galaxies.

</DOC>
<DOC>
<DOCNO> 100218 </DOCNO>
Easy and nearly simultaneous proofs of the Ergodic Theorem and Maximal


  A very short and direct proof along the lines of the Kamae-Katznelson-Weiss
approach.

</DOC>
<DOC>
<DOCNO> 117084 </DOCNO>
Single-bubble sonoluminescence: Shape stability analysis of collapse


  This paper theoretically analyzes the hydrodynamic shape stability problem
for sonoluminescing bubbles. We present a semianalytical approach to describe
the evolution of shape perturbations in the strongly nonlinear regime of
violent collapse. The proposed approximation estimating the damping rate
produced by liquid viscosity is used to elucidate the influence of the collapse
phase on subsequent evolution of the Rayleigh-Taylor instability. We
demonstrate that time derivatives of shape perturbations grow significantly as
the bubble radius vanishes, forming the dominant contribution to
destabilization during the ensuing bounce phase. By this effect the
Rayleigh-Taylor instability can be enhanced drastically, yielding a viable
explanation of the upper threshold of driving pressure experimentally observed
by Barber et al. [Phys. Rev. Lett. 72, 1380 (1994)].

</DOC>
<DOC>
<DOCNO> 70307 </DOCNO>
Can dark matter see itself?


  Many independent high-resolution simulations of structure formation in cold
dark matter models show that galactic halos should have singular core profiles.
This is in stark contrast with observations of both low- and high-surface
brightness galaxies, which indicate that the dark matter has almost constant
density in the central parts of halos. Basically there are three possible
avenues to a solution to the problem, which we discuss in turn. Observations of
halo profiles could be more uncertain than previously thought, and higher
resolution observations could reveal that spirals do have a singular core
feature. The highest resolution simulations do not include a baryonic
component, and it is conceivable that violent star formation processes and
similar phenomena can destroy the singular dark matter core and lead to an
almost constant density core profile. Finally, we discuss in more detail the
intriguing possibility that the discrepancy hints at some new exotic physics of
the dark matter. Warm dark matter and self-interacting dark matter are two of
the most promising candidates.

</DOC>
<DOC>
<DOCNO> 169897 </DOCNO>
Relative entropy in quantum information theory


  We review the properties of the quantum relative entropy function and discuss
its application to problems of classical and quantum information transfer and
to quantum data compression. We then outline further uses of relative entropy
to quantify quantum entanglement and analyze its manipulation.

</DOC>
<DOC>
<DOCNO> 121714 </DOCNO>
The minor axis outflow of NGC 2146


  X-ray and optical observations have shown that the supernova explosions and
stellar winds of the starburst in NGC 2146 produce an outflow of hot material
along the minor axis. This outflow is expected to have a more or less conical
shape, on either side of the galactic plane, and cone walls of cooler material
where the outflow is in shock contact with halo gas. We attempt to determine
the geometry (diameter at the base and opening angle) and the physical
parameters (velocity and density) of the material in the cone walls from the
optical emission line and radio observations presented here, and from published
X-ray, radio, and optical observations. We compare the outflow of NGC 2146 with
the outflow of M 82.

</DOC>
<DOC>
<DOCNO> 12300 </DOCNO>
Spontaneous breaking of axial symmetry for Schroedinger's equation in


  For appropriate parameters, the ground state for the Schroedinger and Ampere
coupled equations in a cylindric domain does not have axial symmetry.

</DOC>
<DOC>
<DOCNO> 102490 </DOCNO>
Endomorphism rings of modules whose cardinality is cofinal to omega


  The main result is
  Theorem: Let A be an R-algebra, mu, lambda be cardinals such that
|A|<=mu=mu^{aleph_0}<lambda<=2^mu. If A is aleph_0-cotorsion-free or A is
countably free, respectively, then there exists an aleph_0-cotorsion-free or a
separable (reduced, torsion-free) R-module G respectively of cardinality
|G|=lambda with End_RG=A oplus Fin G.

</DOC>
<DOC>
<DOCNO> 67966 </DOCNO>
Stochastic Processes and Thermodynamics on Curved Spaces


  Our approach views the thermodynamics and kinetics in general relativity and
extended gravitational theories (with generic local anisotropy) from the
perspective of the theory of stochastic differential equations on curved
spaces.
  Nonequilibrium and irreversible processes in black hole thermodynamics are
considered. The paper summarizes the author's contribution to Journees
Relativistes 99 (12--17 September 1999), Weimar, Germany.

</DOC>
<DOC>
<DOCNO> 120845 </DOCNO>
Chandra observations of NGC 253: New insights into the nature of


  Arcsecond-resolution X-ray imaging of the nucleus of the nearby starburst
galaxy NGC 253 with Chandra reveals a well-collimated, strongly
limb-brightened, kiloparsec-scale conical outflow from the central starburst
region. The outflow is very similar in morphology to the known H-alpha outflow
cone, on scales down to <= 20 pc. This provides, for the first time, robust
evidence that both X-ray and H-alpha emission come from low volume filling
factor regions of interaction between the fast energetic wind of SN-ejecta and
the denser ambient interstellar medium (ISM), and not from the wind fluid
itself. We provide estimates of the (observationally and theoretically
important) filling factor of the X-ray emitting gas, of between 4 and 40 per
cent, consistent with an upper limit of ~40 per cent based directly on the
observed limb-brightened morphology of the outflow. Only <= 20 per cent of the
observed X-ray emission can come from the volume-filling, metal-enriched, wind
fluid itself. Spatially-resolved spectroscopy of the soft diffuse thermal X-ray
emission reveals that the predominant source of spectral variation along the
outflow cones is due to strong variation in the absorption, on scales of < 60
pc, there being little change in the characteristic temperature of the
emission. We show that these observations are easily explained by, and fully
consistent with, the standard model of a superwind driven by a starburst of NGC
253's observed power. If these results are typical of all starburst-driven
winds, then we do not directly see all the energy and gas (in particular the
hot metal-enriched gas) transported out of galaxies by superwinds, even in
X-ray emission.

</DOC>
<DOC>
<DOCNO> 122230 </DOCNO>
Simulations of Merging Clusters of Galaxies


  Numerical simulations of cluster mergers reveal many characteristics of the
merging process: shock structure and strength, observational signatures of the
dynamical state, effects on the mass determination, turbulence and the
evolution of the X-ray luminosity and the magnetic field. In this article I
review the results obtained from various simulations over the last years.

</DOC>
<DOC>
<DOCNO> 13294 </DOCNO>
Temperature dependence of impurity bound states in d-wave


  We study the evolution with temperature of quasiparticle bound states around
non-magnetic impurities in d-wave superconductors. The associated local density
of states has a fourfold symmetry which has recently been observed in Zn-doped
Bi2212 using scanning tunneling microscopy (STM). From the corresponding
Bogoliubov-de Gennes equation we find that with increasing temperature the
magnitude of the bound state energy increases and the amplitude of the fourfold
contribution in the spinor wave functions decreases. In the pseudogap regime
above T_c the fourfold angular dependence of the local tunneling conductance
persists as long as the superconducting fluctuations are sufficiently strong to
support a finite local order parameter. Once the gap function vanishes
completely, the angular structure of the bound state wave function becomes
featureless. These effects should be observable in STM studies of impurity
doped high-temperature superconductors.

</DOC>
<DOC>
<DOCNO> 118222 </DOCNO>
Predicting the Properties of Binary Stellar Systems: The Evolution of


  We investigate the formation of binary stellar systems. We consider a model
where a `seed' protobinary system forms, via fragmentation, within a collapsing
molecular cloud core and evolves to its final mass by accreting material from
an infalling gaseous envelope. This accretion alters the mass ratio and orbit
of the binary, and is largely responsible for forming the circumstellar and/or
circumbinary discs. Given this model for binary formation, we predict the
properties of binary systems and how they depend on the initial conditions
within the molecular cloud core. We predict that there should be a continuous
trend such that closer binaries are more likely to have equal mass components
and are more likely to have circumbinary discs than wider systems. Comparing
our results to observations, we find that the observed mass-ratio distributions
of binaries and the frequency of circumbinary discs as a function of separation
are most easily reproduced if the progenitor molecular cloud cores have radial
density profiles between uniform and 1/r (e.g. Gaussian) with near
uniform-rotation. This is in good agreement with the observed properties of
pre-stellar cores. Conversely, we find that the observed properties of binaries
cannot be reproduced if the cloud cores are in solid-body rotation and have
initial density profiles which are strongly centrally condensed. Finally, in
agreement with the radial-velocity searches for extra-solar planets, we find
that it is very difficult to form a brown dwarf companion to a solar-type star
with a separation < 10 AU, but that the frequency of brown dwarf companions
should increase with larger separations or lower mass primaries.

</DOC>
<DOC>
<DOCNO> 85264 </DOCNO>
The Location and Temperature of Event Horizon for General Black Hole via


  In this paper, we investigate the general case of black hole on horizon by
the method of Damour-Ruffini-Zhao. The proof of identification of the location
of horizons determined both by Damour-Ruffini-Zhao's (D-R-Z) method and by
equation of null super-surface is given. The formula of temperature on the
horizon for general black holes is obtained and is successfully checked by a
variety of models of black holes.

</DOC>
<DOC>
<DOCNO> 152432 </DOCNO>
Hidden Symmetries, Central Charges and All That


  In this review we discuss hidden symmetries of toroidal compactifications of
eleven-dimensional supergravity. We recall alternative versions of this theory
which exhibit traces of the hidden symmetries when still retaining the massive
Kaluza-Klein states. We reconsider them in the broader perspective of M-theory
which incorporates a more extended variety of BPS states. We also argue for a
new geometry that may underly these theories. All our arguments point towards
an extension of the number of space-time coordinates beyond eleven.

</DOC>
<DOC>
<DOCNO> 40217 </DOCNO>
ICANOE and OPERA experiments at the LNGS/CNGS


  We discuss two experiments ICANOE and OPERA that have been proposed within
the context of long-baseline and atmospheric neutrino experiments in Europe.
The joint ICANOE/OPERA program aims at further improving our understanding of
the effect seen in atmospheric neutrinos. This program is based on (1) a
continuation of the observation of atmospheric neutrinos with the improved
technique of ICANOE/ICARUS (2) a sensitive numu->nue and numu->nutau appearance
program with the accelerator neutrinos coming from CERN (CNGS) from a distance
of 730 km.

</DOC>
<DOC>
<DOCNO> 80776 </DOCNO>
P-Vortices, Gauge Copies, and Lattice Size


  We study the dependence of the center-projected string tension on both the
lattice size, and the number of gauge copies used for maximal center gauge
fixing. We show that a recent finding of Bornyakov, Komarov, Polikarpov, and
Veselov (hep-lat/0002017), indicating a substantial breakdown of center
dominance in maximal center gauge, is only obtained for rather small lattice
volumes, and is not found in numerical simulations on larger lattices. It is
shown that center-projected Creutz ratios approach the full asymptotic string
tension as lattice size increases, and that the P-vortex density is consistent,
at moderately weak couplings, with 2-loop scaling behavior.

</DOC>
<DOC>
<DOCNO> 8556 </DOCNO>
Features of first passage time density function for coherent stochastic


  Coherent stochastic resonance is explained in terms of first passage time
density functions. Scaling relation between first passage time density
functions at resonance for different lengths of the medium is obtained. A
formula for first passage time density function at resonance is derived in
terms of two universal functions, which demonstrates the universal feature of
coherent stochastic resonance. A simple approximate expression for first
passage time density function at resonance is proposed which is shown to
explain the behavior at resonance fairly accurately.

</DOC>
<DOC>
<DOCNO> 68526 </DOCNO>
Charged Particle Ratio Fluctuation as a Signal for QGP


  In this letter we argue that the event-by-event fluctuations of the ratio of
the positively charged and the negatively charged pions provides a signal of
quark-gluon plasma. The fact that quarks carry fractional charges is ultimately
responsible for this distinct signal.

</DOC>
<DOC>
<DOCNO> 13197 </DOCNO>
NMR relaxation rates in spin-1/2 antiferromagnetic chains


  We consider the low-temperature behavior of NMR relaxation rates $T_1$ and
$T_{2G}$ in the spin-1/2 antiferromagnetic chain. We find that $T_1 \propto
const$ and $T_{2G} \propto \sqrt{T}$, with logarithmic corrections. We
determine both constants and logarithmic terms by matching perturbative RG with
exact results, so that the final expressions for the relaxation rates do not
contain any free parameters. Our theoretical results are in excellent agreement
with NMR experiments in Sr$_2$CuO$_3$.

</DOC>
<DOC>
<DOCNO> 13694 </DOCNO>
Phase-coherence threshold and vortex-glass state in diluted


  We study numerically the interplay of phase coherence and vortex-glass state
in two-dimensional Josephson-junction arrays with average rational values of
flux quantum per plaquette $f$ and random dilution of junctions. For $f=1/2$,
we find evidence of a phase coherence threshold value $x_s$, below the
percolation concentration of diluted junctions $x_p$, where the superconducting
transition vanishes. For $x_s < x < x_p$ the array behaves as a
zero-temperature vortex glass with nonzero linear resistance at finite
temperatures. The zero-temperature critical currents are insensitive to
variations in $f$ in the vortex glass region while they are strongly $f$
dependent in the phase coherent region.

</DOC>
<DOC>
<DOCNO> 116417 </DOCNO>
The Hawking-Unruh Temperature and Quantum Fluctuations in Particle


  We wish to draw attention to a novel view of the effect of the quantum
fluctuations during the radiation of accelerated particles, particularly those
in storage rings. This view is inspired by the remarkable insight of Hawking
that the effect of the strong gravitational field of a black hole on the
quantum fluctuations of the surrounding space is to cause the black hole to
radiate with a temperature T = hbar g / 2 pi c k, where g is the acceleration
due to gravity at the surface of the black hole, c is the speed of light, and k
is Boltzmann's constant. Shortly thereafter Unruh argued that an accelerated
observer should become excited by quantum fluctuations to a temperature T =
hbar a* / 2 pi c k, where a* is the acceleration of the observer in its
instantaneous rest frame. In a series of papers Bell and co-workers have noted
that electron storage rings provide a demonstration of the utility of the
Hawking-Unruh temperature, with emphasis on the question of the incomplete
polarization of the electrons due to quantum fluctuations of synchrotron
radiation. Here we expand slightly on the results of Bell et al., and encourage
the reader to consult the literature for more detailed understanding.

</DOC>
<DOC>
<DOCNO> 179016 </DOCNO>
Parity Violation in Low-Energy np->d gamma and the Deuteron Anapole


  Parity violation in low-energy nuclear observables is included in the
pionless effective field theory. The model-independent relation between the
parity-violating asymmetry in polarized np -> d gamma and the non-nucleon part
of the deuteron anapole moment is discussed. The asymmetry in np -> d gamma
computed with KSW power-counting, and recently criticized by Desplanques, is
discussed.

</DOC>
<DOC>
<DOCNO> 39860 </DOCNO>
The masses of elementary particles and hadrons


  The masses of elementary particles and hadrons can be calculated from the
periodic table of elementary particles. The periodic table is derived from
dimensional hierarchy for the seven extra spatial dimensions. As a molecule is
the composite of atoms with chemical bonds, a hadron is the composite of
elementary particles with hadronic bonds. The masses of elementary particles
and hadrons can be calculated using the periodic table with only four known
constants: the number of the extra spatial dimensions in the superstring, the
mass of electron, the mass of Z=B0, and the fine structure constant. The
calculated masses are in good agreement with the observed values. For examples,
the calculated masses for the top quark, neutron, and pion are 176.5 GeV,
939.54MeV, and 135.01MeV in excellent agreement with the observed masses, 176
=B1 13 GeV, 939.57 MeV, and 134.98 MeV, respectively. The masses of 110 hadrons
are calculated. The overall average difference between the calculated masses
and the observed masses for all hadrons is 0.29 MeV. The periodic table of
elementary particles provides the most comprehensive explanation and
calculation for the masses of elementary particles and hadrons.

</DOC>
<DOC>
<DOCNO> 9304 </DOCNO>
Dynamics near the Surface Reconstruction of W(100)


  Using Brownian molecular dynamics simulation, we study the surface dynamics
near the reconstruction transition of W(100) via a model Hamiltonian. Results
for the softening and broadening of the surface phonon spectrum near the
transition are compared with previous calculations and with He atom scattering
data. From the critical behavior of the central peak in the dynamical structure
factor, we also estimate the exponent of the power law anomaly for adatom
diffusion near the transition temperature.

</DOC>
<DOC>
<DOCNO> 68983 </DOCNO>
A quasi unitarity bound on the radion mass in the Randall-Sundrum model


  In this paper we derive a quasi unitarity bound on the radion mass ($\mphi$)
from the process $hh\to \phi\phi$. We find that at sufficiently high energies
(i.e. when $ s\gg m_h^2, \mphi^2 $) the J=0 partial wave amplitude for the
above process violates unitarity if $\mphi^2 > m_h^2+16 \pi \vphi^2 $.
Combining this result with the unitarity bound $m_h^2<{16\pi v\vphi\over 3}$
obtained from the process $hh\to h\phi$ we get an upper bound of $4\sqrt
{\pi}\vphi [1+{v\over 3 \vphi}]^{1\over 2}$ on the radion mass. This bound is
however valid only in the low energy effective theory where we can ignore the
effects of the gravitational KK modes and the string/M theoretic excitations.

</DOC>
<DOC>
<DOCNO> 8566 </DOCNO>
Luther-Emery Stripes, RVB Spin Liquid Background and High Tc


  The stripe phase in high Tc cuprates is modeled as a single stripe coupled to
the RVB spin liquid background by the single particle hopping process. In
normal state, the strong pairing correlation inherent in RVB state is thus
transfered into the Luttinger stripe and drives it toward spin-gap formation
described by Luther-Emery Model. The establishment of global phase coherence in
superconducting state contributes to a more relevant coupling to
  Luther-Emery Stripe and leads to gap opening in both spin and charge sectors.
Physical consequences of the present picture are discussed, and emphasis is put
on the unification of different energy scales relevant to cuprates, and good
agreement is found with the available experimental results, especially in
ARPES.

</DOC>
<DOC>
<DOCNO> 122515 </DOCNO>
The solar dynamo: old, recent, and new problems


  A number of problems of solar and stellar dynamo theory are briefly reviewed
and the current status of possible solutions is discussed. Results of direct
numerical simulations are described in view of mean-field dynamo theory and the
relation between the alpha-effect and the inverse cascade of magnetic helicity
is highlighted. The possibility of `catastrophic' quenching of the alpha-effect
is explained in terms of the constraint placed by the conservation of magnetic
helicity.

</DOC>
<DOC>
<DOCNO> 12339 </DOCNO>
Pressure-Temperature Phase Diagram of Generalized Hubbard Model with


  In the present paper pressure-temperature phase diagram of a generalized
Hubbard model with correlated hopping in a paramagnetic state at half-filling
is determined by means of the generalized mean-field approximation in the Green
function technique. The constructed phase diagram describes metal-to-insulator
transition with increasing temperature, and insulator-to-metal transition under
the action of external pressure. The phase diagram can explain paramagnetic
region of the phase diagrams of some transition metal compounds. We have found
that taking into account correlated hopping allows much better description of
these experimental data than the Hubbard model; this testifies also much better
physics of the present model and the important role of correlated hopping.

</DOC>
<DOC>
<DOCNO> 70293 </DOCNO>
Consistent OPE Description of Gluon Two- and Three-point Green Function?


  We perform an OPE analysis of the flavorless non-perturbative gluon
propagator and the symmetric three-gluon vertex in the Landau gauge. The first
subdominant operator is $A_\mu A^\mu$ which can condensate in the Landau gauge
``vacuum'' although being a non-gauge invariant operator. We neglect all higher
dimension operators. Then the gluon propagator and the symmetric three gluon
vertex only depend on one common unknown condensate. We propose a consistency
check from lattice data. At two loops for the leading coefficient and with
$1/p^2$ corrections at tree-level order the two fitted values for the
condensate do not agree. At three loops we argue that the today unknown
$\beta_2^{\rm MOM}$ should be equal to $1.5(3)\times \beta_2^{\widetilde{\rm
MOM}}=7400(1500)$ to fulfill the OPE relation. Inclusion of the power
corrections' anomalous dimensions should improve further the agreement. We show
that these techniques cannot be applied to the asymmetric three gluon vertex
with one vanishing momentum.

</DOC>
<DOC>
<DOCNO> 67867 </DOCNO>
Radiative Corrections to scalar quark decays in the MSSM


  We review the one-loop corrections to the partial decay width of
sbottom-quark into a top quark and a chargino for the parameter space relevant
to the TESLA e+e- linear collider. We present the results available in the
literature for the QCD and the Yukawa coupling corrections in a unified
framework. In this way a direct comparison of the size of the various
corrections is possible.

</DOC>
<DOC>
<DOCNO> 70691 </DOCNO>
Extra Dimensions and Compositeness as a Basis for Hierarchy in Quark


  Strong gauge and top-Yukawa couplings predicted in the presence of extra
dimensions lead to a trickle-down effect of the top-coupling through the
renormalization group equations for the quark Yukawa matrices. The matrix
elements for the u and d-quarks get progressively smaller as one moves away
from the dominant (33)-element revealing a hierarchical pattern for the mass
matrices.

</DOC>
<DOC>
<DOCNO> 40255 </DOCNO>
Phenomenology of a New Minimal Supersymmetric Extension of the Standard


  We study the phenomenology of a new Minimally-extended Supersymmetric
Standard Model (nMSSM) where a gauge singlet superfield is added to the MSSM
spectrum. The superpotential of this model contains no dimensionful parameters,
thus solving the mu-problem of the MSSM. A global discrete R-symmetry,
forbidding the cubic singlet self-interaction, imposed on the complete theory,
guarantees its stability with respect to generated higher-order tadpoles of the
singlet and solves both the domain wall and Peccei-Quinn axion problems. We
give the free parameters of the model and display some general constraints on
them. A particular attention is devoted to the neutralino sector where a
(quasi-pure) singlino appears to be always the LSP of the model, leading to
additional cascades, involving the NLSP -> LSP transition, compared with the
MSSM. We then present the upper bounds on the masses of the lightest and
next-to-lightest -- when the lightest is an invisible singlet -- CP-even Higgs
bosons, including the full one-loop and dominant two-loop corrections. These
bounds are found to be much higher than the equivalent ones in the MSSM.
Finally, we discuss some phenomenological implications for the Higgs sector of
the nMSSM in Higgs production at future hadron colliders.

</DOC>
<DOC>
<DOCNO> 122780 </DOCNO>
Large-Scale Primordial Magnetic Fields from Inflation and Preheating


  We consider models in which the (transverse) photon mass is non-zero during
inflation and drops to zero non-adiabatically at the end of inflation. Through
this process, vacuum fluctuations of the photon field are converted into
physical, long-wavelength modes with high amplitude. The resulting spectrum of
the field strength is approximately B_l ~ 1/l, where l is the relevant
coherence scale. With a reasonable model of field evolution we obtain, on
comoving galactic scales, a magnetic field strong enough to seed a dynamo
mechanism and generate the observed galactic magnetic fields.

</DOC>
<DOC>
<DOCNO> 80627 </DOCNO>
Supersymmetric Yang-Mills Theories from Domain Wall Fermions


  We present work in progress on employing domain wall fermions to simulate N=1
supersymmetric Yang-Mills theories on the lattice in d=4 and d=3 dimensions.
The geometrical nature of domain wall fermions gives simple insights into how
to construct these theories. We also discuss the obstacles associated with
simulating the N=2 theory in d=4.

</DOC>
<DOC>
<DOCNO> 85250 </DOCNO>
Statistical Mechanics of 2+1 Gravity From Riemann Zeta Function and


  In the recent publication (Journal of Geometry and Physics,33(2000)23-102) we
demonstrated that dynamics of 2+1 gravity can be described in terms of train
tracks. Train tracks were introduced by Thurston in connection with description
of dynamics of surface automorphisms. In this work we provide an example of
utilization of general formalism developed earlier. The complete exact solution
of the model problem describing equilibrium dynamics of train tracks on the
punctured torus is obtained. Being guided by similarities between the dynamics
of 2d liquid crystals and 2+1 gravity the partition function for gravity is
mapped into that for the Farey spin chain. The Farey spin chain partition
function, fortunately, is known exactly and has been thoroughly investigated
recently. Accordingly, the transition between the pseudo-Anosov and the
periodic dynamic regime (in Thurston's terminology) in the case of gravity is
being reinterpreted in terms of phase transitions in the Farey spin chain whose
partition function is just a ratio of two Riemann zeta functions. The mapping
into the spin chain is facilitated by recognition of a special role of the
Alexander polynomial for knots/links in study of dynamics of self
homeomorphisms of surfaces. At the end of paper, using some facts from the
theory of arithmetic hyperbolic 3-manifolds (initiated by Bianchi in 1892), we
develop systematic extension of the obtained results to noncompact Riemannian
surfaces of higher genus. Some of the obtained results are also useful for 3+1
gravity. In particular, using the theorem of Margulis, we provide new reasons
for the black hole existence in the Universe: black holes make our Universe
arithmetic. That is the discrete Lie groups of motion are arithmetic.

</DOC>
<DOC>
<DOCNO> 9144 </DOCNO>
Planar cracks in the fuse model


  We simulate the propagation of a planar crack in a quasi-two dimensional fuse
model, confining the crack between two horizontal plates. We investigate the
effect on the roughness of microcrack nucleation ahead of the main crack and
study the structure of the damage zone. The two dimensional geometry introduces
a characteristic length in the problem, limiting the crack roughness. The
damage ahead of the crack does not appear to change the scaling properties of
the model, which are well described by gradient percolation.

</DOC>
<DOC>
<DOCNO> 99862 </DOCNO>
Spectral Properties of Non-Self-Adjoint Operators in the Semi-classical


  We give a spectral description of the semi-classical Schrodinger operator
with a piecewise linear, complex valued potential. Moreover, using these
results, we show how an arbitrarily small bounded perturbation of a
non-self-adjoint operator can completely change the spectrum of the operator.

</DOC>
<DOC>
<DOCNO> 8601 </DOCNO>
A new class of integrable diffusion-reaction processes


  We consider a process in which there are two types of particles, A and B, on
an infinite one-dimensional lattice. The particles hop to their adjacent sites,
like the totally asymmetric exclusion process (ASEP), and have also the
following interactions: A+B -> B+B and B+A -> B+B, all occur with equal rate.
We study this process by imposing four boundary conditions on ASEP master
equation. It is shown that this model is integrable, in the sense that its
N-particle S-matrix is factorized into a product of two-particle S-matrices
and, more importantly, the two-particle S-matrix satisfy quantum Yang-Baxter
equation. Using coordinate Bethe-ansatz, the N-particle wavefunctions and the
two-particle conditional probabilities are found exactly.
  Further, by imposing four reasonable physical conditions on two-species
diffusion-reaction processes (where the most important ones are the equality of
the reaction rates and the conservation of the number of particles in each
reaction), we show that among the 4096 types of the interactions which have
these properties and can be modeled by a master equation and an appropriate set
of boundary conditions, there are only 28 independent interactions which are
integrable. We find all these interactions and also their corresponding wave
functions. Some of these may be new solutions of quantum Yang-Baxter equation.

</DOC>
<DOC>
<DOCNO> 120018 </DOCNO>
On the Seyfert 2 warm and cool infrared dichotomy


  An optical spectropolarimetric study has shown that the detectability of
polarised broad H-alpha in Seyfert 2 galaxies is correlated to the IRAS f60/f25
flux ratio where only those Seyfert 2s with "warm" IRAS colours show polarised
broad line emission. It was suggested that those Seyfert 2s with "cool" IRAS
colours have highly inclined tori which obscure the broad line scattering
screen.
  I present here hard X-ray observations inconsistent with this picture showing
that the derived column densities of warm and cool Seyfert 2 galaxies are
statistically the same. I suggest that the IRAS f60/f25 flux ratio is more
consistent with implying the relative strength of galactic to Seyfert emission
and provide supporting evidence for this view.

</DOC>
<DOC>
<DOCNO> 70692 </DOCNO>
Analysis of the QCD-improved factorization in B -> J/\psi K


  We consider the exclusive decay $B\to J/\psi K$ using the QCD-improved
factorization method in the heavy quark limit. It is shown that the decay
amplitude is factorizable in this limit and nonfactorizable contributions are
calculable from first principles in perturbation theory. Also the spectator
contributions at order $\alpha_s$ are finite and suppressed in the heavy quark
limit. We present the result at next-to-leading order in strong interaction,
and leading order in $1/m_b$ in the heavy quark limit.

</DOC>
<DOC>
<DOCNO> 99457 </DOCNO>
An Application of the Whitehouse Module to Riffle Shuffles Followed by a


  Using representation theoretic work on the Whitehouse module, a formula is
obtained for the cycle structure of a riffle shuffle followed by a cut. This
result will be merged with the paper [F6].

</DOC>
<DOC>
<DOCNO> 68642 </DOCNO>
The weak angle gamma from one-particle inclusive CP asymmetries in the


  We compute CP asymmetries of one-particle inclusive B(s) --> D(s) X decay
rates. We find that the weak angle gamma could in principle be extracted from
these asymmetries although they are very small. Taking the decay width
difference into account, we find that the time integrated CP asymmetries are of
the order A=1.4 10^(-4) sin(gamma). Some large uncertainties remain due to the
lack of experimental data.

</DOC>
<DOC>
<DOCNO> 178644 </DOCNO>
G-Matrix Equation in the Resonating-Group Method


  The G-matrix equation is most straightforwardly formulated in the
resonating-group method if the quark-exchange kernel is directly used as the
driving term for the infinite sum of all the ladder diagrams. The inherent
energy-dependence involved in the exchange term of the normalization kernel
plays the essential role to define the off-shell T-matrix uniquely when the
complete Pauli-forbidden state exists. We analyze this using a simple solvable
model with no quark-quark interaction, and calculating the most general
T-matrix in the formulation developed by Noyes and Kowalski. This formulation
gives a certain condition for the existence of the solution in the
Lippmann-Schwinger resonating-group method. A new procedure to deal with the
corrections for the reduced masses and the internal-energy terms in the Lambda
N - Sigma N coupled-channel resonating-group equation is proposed.

</DOC>
<DOC>
<DOCNO> 12086 </DOCNO>
Diffusion limited aggregation as a Markovian process: site-sticking


  Cylindrical lattice diffusion limited aggregation (DLA), with a narrow width
N, is solved for site-sticking conditions using a Markovian matrix method
(which was previously developed for the bond-sticking case). This matrix
contains the probabilities that the front moves from one configuration to
another at each growth step, calculated exactly by solving the Laplace equation
and using the proper normalization. The method is applied for a series of
approximations, which include only a finite number of rows near the front. The
fractal dimensionality of the aggregate is extrapolated to a value near 1.68.

</DOC>
<DOC>
<DOCNO> 120685 </DOCNO>
Optical Spectroscopy of GX339-4 during the High-Soft and Low-Hard States


  We have carried out observations of the X-ray transient GX339-4 during its
high-soft and low-hard X-ray spectral states. Our high-resolution spectroscopic
observation in 1999 April suggests that the H-alpha line has a single-peaked
profile in the low-hard state as speculated in our previous paper. The HeII
4686 line, however, has a double-peaked profile in both the high-soft and
low-hard states. This suggests that the line-emission mechanism is different in
the two states. Our interpretation is that double-peaked lines are emitted from
a temperature-inversion layer on the accretion-disk surface when it is
irradiatively heated by soft X-rays. Single-peaked lines may be emitted from
outflow/wind matter driven by hard X-ray heating. We have constructed a simple
plane-parallel model and we use it to illustrate that a temperature-inversion
layer can be formed at the disk surface under X-ray illumination. We also
discuss the conditions required for the formation of temperature inversion and
line emission. Based on the velocity separations measured for the double-peaked
lines in the high-soft state, we propose that GX339-4 is a low-inclination
binary system. The orbital inclination is about 15 deg if the orbital period is
14.8 hours.

</DOC>
<DOC>
<DOCNO> 169999 </DOCNO>
Quantum remote control: Teleportation of unitary operations


  We consider the implementation of an arbitrary unitary operation U upon a
distant quantum system. This teleportation of U can be viewed as a quantum
remote control. We investigate protocols which achieve this using local
operations, classical communication and shared entanglement (LOCCSE). Lower
bounds on the necessary entanglement and classical communication are determined
using causality and the linearity of quantum mechanics. We examine in
particular detail the resources required if the remote control is to be
implemented as a classical black box. Under these circumstances, we prove that
the required resources are, necessarily, those needed for implementation by
bidirectional state teleportation.

</DOC>
<DOC>
<DOCNO> 9889 </DOCNO>
Phonon Dispersion Effects and the Thermal Conductivity Reduction in


  The experimentally observed order-of-magnitude reduction in the thermal
conductivity along the growth axis of (GaAs)_n/(AlAs)_n (or n x n)
superlattices is investigated theoretically for (2x2), (3x3) and (6x6)
structures using an accurate model of the lattice dynamics. The modification of
the phonon dispersion relation due to the superlattice geometry leads to
flattening of the phonon branches and hence to lower phonon velocities. This
effect is shown to account for a factor-of-three reduction in the thermal
conductivity with respect to bulk GaAs along the growth direction; the
remainder is attributable to a reduction in the phonon lifetime. The
dispersion-related reduction is relatively insensitive to temperature (100 < T
< 300K) and n. The phonon lifetime reduction is largest for the (2x2)
structures and consistent with greater interface scattering. The thermal
conductivity reduction is shown to be appreciably more sensitive to GaAs/AlAs
force constant differences than to those associated with molecular masses.

</DOC>
<DOC>
<DOCNO> 9609 </DOCNO>
A Monte Carlo Formulation of the Bogolubov Theory


  We propose an efficient stochastic method to implement numerically the
Bogolubov approach to study finite-temperature Bose-Einstein condensates. Our
method is based on the Wigner representation of the density matrix describing
the non condensed modes and a Brownian motion simulation to sample the Wigner
distribution at thermal equilibrium. Allowing to sample any density operator
Gaussian in the field variables, our method is very general and it applies both
to the Bogolubov and to the Hartree-Fock Bogolubov approach, in the equilibrium
case as well as in the time-dependent case. We think that our method can be
useful to study trapped Bose-Einstein condensates in two or three spatial
dimensions without rotational symmetry properties, as in the case of
condensates with vortices, where the traditional Bogolubov approach is
difficult to implement numerically due to the need to diagonalize very big
matrices.

</DOC>
<DOC>
<DOCNO> 12612 </DOCNO>
Putting Proteins back into Water


  We introduce a simplified protein model where the solvent (water) degrees of
freedom appear explicitly (although in an extremely simplified fashion). Using
this model we are able to recover the thermodynamic phenomenology of proteins
over a wide range of temperatures. In particular we describe both the warm and
the {\it cold} protein denaturation within a single framework, while addressing
important issues about the structure of model proteins.

</DOC>
<DOC>
<DOCNO> 39700 </DOCNO>
Measurement of the B0 and B+ meson masses from B0 -> psi(') K_S and B+


  Using 9.6 million B meson pairs collected with the CLEO detector, we have
fully reconstructed 135 B0 -> psi(') K_S and 526 B+ -> psi(') K+ candidates
with very low background.
 We fitted the psi(')K invariant mass distributions of these B meson candidates
and measured the masses of the neutral and charged B mesons to be
M(B0)=5279.1+-0.7[stat]+-0.3[syst] MeV/c^2 and
M(B+)=5279.1+-0.4[stat]+-0.4[syst] MeV/c^2. The precision is a significant
improvement over previous measurements.

</DOC>
<DOC>
<DOCNO> 170054 </DOCNO>
On Quantum Detection and the Square-Root Measurement


  In this paper we consider the problem of constructing measurements optimized
to distinguish between a collection of possibly non-orthogonal quantum states.
We consider a collection of pure states and seek a positive operator-valued
measure (POVM) consisting of rank-one operators with measurement vectors
closest in squared norm to the given states. We compare our results to previous
measurements suggested by Peres and Wootters [Phys. Rev. Lett. 66, 1119 (1991)]
and Hausladen et al. [Phys. Rev. A 54, 1869 (1996)], where we refer to the
latter as the square-root measurement (SRM). We obtain a new characterization
of the SRM, and prove that it is optimal in a least-squares sense. In addition,
we show that for a geometrically uniform state set the SRM minimizes the
probability of a detection error. This generalizes a similar result of Ban et
al. [Int. J. Theor. Phys. 36, 1269 (1997)].

</DOC>
<DOC>
<DOCNO> 151570 </DOCNO>
Overview Of K-Theory Applied To Strings


  K-theory provides a framework for classifying Ramond-Ramond (RR) charges and
fields. K-theory of manifolds has a natural extension to K-theory of
noncommutative algebras, such as the algebra considered in noncommutative
Yang-Mills theory or in open string field theory. In a number of concrete
problems, the K-theory analysis proceeds most naturally if one starts out with
an infinite set of D-branes, reduced by tachyon condensation to a finite set.
This suggests that string field theory should be reconsidered for N=infinity.

</DOC>
<DOC>
<DOCNO> 70063 </DOCNO>
Scalar Mesons in a Chiral Quark Model with Glueball


  Ground-state scalar isoscalar mesons and a scalar glueball are described in a
U(3)xU(3) chiral quark model of the Nambu--Jona-Lasinio (NJL) type with 't
Hooft interaction. The latter interaction produces singlet-octet mixing in the
scalar and pseudoscalar sectors. The glueball is introduced into the effective
meson Lagrangian as a dilaton on the base of scale invariance. The mixing of
the glueball with scalar isoscalar quarkonia and amplitudes of their decays
into two pseudoscalar mesons are shown to be proportional to current quark
masses, vanishing in the chiral limit. Mass spectra of the scalar mesons and
the glueball and their main modes of strong decay are described.

</DOC>
<DOC>
<DOCNO> 13882 </DOCNO>
Critical spin dynamics of the 2D quantum Heisenberg antiferromagnets:


  We report a neutron scattering study of the long-wavelength dynamic spin
correlations in the model two-dimensional $S=1/2$ square lattice Heisenberg
antiferromagnets Sr$_2$CuO$_2$Cl$_2$ and Sr$_2$Cu$_3$O$_4$Cl$_2$. The
characteristic energy scale, $\omega_0 (T/J)$, is determined by measuring the
quasielastic peak width in the paramagnetic phase over a wide range of
temperature ($0.2 \alt T/J \alt 0.7$). The obtained values for $\omega_0 (T/J)$
agree {\it quantitatively} between the two compounds and also with values
deduced from quantum Monte Carlo simulations. The combined data show scaling
behavior, $\omega \sim \xi^{-z}$, over the entire temperature range with
$z=1.0(1)$, in agreement with dynamic scaling theory.

</DOC>
<DOC>
<DOCNO> 71563 </DOCNO>
N* Mass Spectrum from an Anisotropic Action


  Results are reported for N* masses in the 1/2+ and 1/2- sectors on an
anisotropic lattice. The gauge action is the usual plaquette plus rectangle
type, the quark action is of the D234 type, both having tadpole-improved
tree-level coefficients. Clear splittings from the nucleon ground state are
observed with smeared operators and 500 configurations. The first excited
states in each channel are further isolated, using a correlation matrix and the
variational method. The basic pattern of these splittings is consistent with
experimental observations.

</DOC>
<DOC>
<DOCNO> 69223 </DOCNO>
Scalar Electrodynamics in Framework of Randall-Sundrum Model


  Considering the Randall-Sundrum background, we calculate the total
cross-section for $\phi\phi ^\star \to G \gamma$ in the framework of the scalar
electrodynamics.

</DOC>
<DOC>
<DOCNO> 123176 </DOCNO>
Final Results from the Hubble Space Telescope Key Project to Measure the


  We present here the final results of the Hubble Space Telescope Key Project
to measure the Hubble constant. We summarize our method, the results and the
uncertainties, tabulate our revised distances, and give the implications of
these results for cosmology. The analysis presented here benefits from a number
of recent improvements and refinements, including (1) a larger LMC Cepheid
sample to define the fiducial period-luminosity (PL) relations, (2) a more
recent HST Wide Field and Planetary Camera 2 (WFPC2) photometric calibration,
(3) a correction for Cepheid metallicity, and (4) a correction for
incompleteness bias in the observed Cepheid PL samples. New, revised distances
are given for the 18 spiral galaxies for which Cepheids have been discovered as
part of the Key Project, as well as for 13 additional galaxies with published
Cepheid data. The new calibration results in a Cepheid distance to NGC 4258 in
better agreement with the maser distance to this galaxy. Based on these revised
Cepheid distances, we find values (in km/sec/Mpc) of H0 = 71 +/- 2 (random) +/-
6 (systematic) (type Ia supernovae), 71 +/- 2 +/- 7 (Tully-Fisher relation), 70
+/- 5 +/- 6 (surface brightness fluctuations), 72 +/- 9 +/- 7 (type II
supernovae), and 82 +/- 6 +/- 9 (fundamental plane). We combine these results
for the different methods with 3 different weighting schemes, and find good
agreement and consistency with H0 = 72 +/- 8. Finally, we compare these results
with other, global methods for measuring the Hubble constant.

</DOC>
<DOC>
<DOCNO> 102862 </DOCNO>
Monodromy Representations of the Braid Group


  Chiral conformal blocks in a rational conformal field theory are a far going
extension of Gauss hypergeometric functions. The associated monodromy
representations of Artin's braid group capture the essence of the modern view
on the subject, which originates in ideas of Riemann and Schwarz. Physically,
such monodromy representations correspond to a new type of braid group
statistics, which may manifest itself in two-dimensional critical phenomena,
e.g. in some exotic quantum Hall states. The associated primary fields satisfy
R-matrix exchange relations. The description of the internal symmetry of such
fields requires an extension of the concept of a group, thus giving room to
quantum groups and their generalizations. We review the appearance of braid
group representations in the space of solutions of the Knizhnik - Zamolodchikov
equation, with an emphasis on the role of a regular basis of solutions which
allows us to treat the case of indecomposable representations as well.

</DOC>
<DOC>
<DOCNO> 117389 </DOCNO>
The Angular Momentum Evolution of Very Low Mass Stars


  We present theoretical models of the angular momentum evolution of very low
mass stars (0.1 - 0.5 M_sun) and solar analogues (0.6 - 1.1 M_sun). We
investigate the effect of rotation on the effective temperature and luminosity
of these stars. We find that the decrease in T_eff and L can be significant at
the higher end of our mass range, but becomes negligible below 0.4 M_sun.
Formulae for relating T_eff to mass and v_rot are presented.
  We compare our models to rotational data from young open clusters of
different ages to infer the rotational history of low mass stars, and the
dependence of initial conditions and rotational evolution on mass. We find that
the qualitative conclusions for stars below 0.6 M_sun do not depend on the
assumptions about internal angular momentum transport, which makes these low
mass stars ideal candidates for the study of the angular momentum loss law and
distribution of initial conditions. We find that neither models with solid body
nor differential rotation can simultaneously reproduce the observed stellar
spin down in the 0.6 to 1.1 M_sun mass range and for stars between 0.1 and 0.6
M_sun. The most likely explanation is that the saturation threshold drops more
steeply at low masses than would be predicted with a simple Rossby scaling. In
young clusters there is a systematic increase in the mean rotation rate with
decreased temperature below 3500 K (0.4 M_sun). This suggests either
inefficient angular momentum loss or mass-dependent initial conditions for
stars near the fully convective boundary. (abridged)

</DOC>
<DOC>
<DOCNO> 71470 </DOCNO>
The Minimal Model of Nonbaryonic Dark Matter: A Singlet Scalar


  We propose the simplest possible renormalizable extension of the Standard
Model - the addition of just one singlet scalar field - as a minimalist model
for non-baryonic dark matter. Such a model is characterized by only three
parameters in addition to those already appearing within the Standard Model: a
dimensionless self-coupling and a mass for the new scalar, and a dimensionless
coupling, \lambda, to the Higgs field. If the singlet is the dark matter, these
parameters are related to one another by the cosmological abundance constraint,
implying that the coupling of the singlet to the Higgs field is large, \lambda
\sim O(0.1 - 1). Since this parameter also controls couplings to ordinary
matter, we obtain predictions for the elastic cross section of the singlet with
nuclei. The resulting scattering rates are close to current limits from both
direct and indirect searches. The existence of the singlet also has
implications for current Higgs searches, as it gives a large contribution to
the invisible Higgs width for much of parameter space. These scalars can be
strongly self-coupled in the cosmologically interesting sense recently proposed
by Spergel and Steinhardt, but only for very low masses (< 1 GeV), which is
possible only at the expense of some fine-tuning of parameters.

</DOC>
<DOC>
<DOCNO> 8161 </DOCNO>
Some Exact Results on the Ultrametric Overlap Distribution in Mean Field


  The mean field spin glass model is analyzed by a combination of
mathematically rigororous methods and a powerful Ansatz. The method exploited
is general, and can be applied to others disordered mean field models such as,
e.g., neural networks.
  It is well known that the probability measure of overlaps among replicas
carries the whole physical content of these models. A functional order
parameter of Parisi type is introduced by rigorous methods, according to
previous works by F. Guerra. By the Ansatz that the functional order parameter
is the correct order parameter of the model, we explicitly find the full
overlap distribution. The physical interpretation of the functional order
parameter is obtained, and ultrametricity of overlaps is derived as a natural
consequence of a branching diffusion process.
  It is shown by explicit construction that ultrametricity of the 3-replicas
overlap distribution together with the Ghirlanda-Guerra relations determines
the distribution of overlaps among s replicas, for any s, in terms of the
one-overlap distribution.

</DOC>
<DOC>
<DOCNO> 71337 </DOCNO>
The initial state of ultra-relativistic heavy ion collision


  A model for energy, pressure and flow velocity distributions at the beginning
of ultra-relativistic heavy ion collisions is presented, which can be used as
an initial condition for hydrodynamic calculations. Our model takes into
account baryon recoil for both target and projectile, arising from the
acceleration of partons in an effective field, produced in the collision. The
typical field strength (string tension) for RHIC energies is about 5-12 GeV/fm,
what allows us to talk about "string ropes". The results show that a QGP forms
a tilted disk, such that the direction of the largest pressure gradient stays
in the reaction plane, but deviates from both the beam and the usual transverse
flow directions. Such initial conditions may lead to the creation of "antiflow"
or "third flow component".

</DOC>
<DOC>
<DOCNO> 12918 </DOCNO>
Numerical Study of Aging in the Generalized Random Energy Model


  Magnetizations are introduced to the Generalized Random Energy Model (GREM)
and numerical simulations on ac susceptibility is made for direct comparison
with experiments in glassy materials. Prominent dynamical natures of spin
glasses, {\it i.e.}, {\em memory} effect and {\em reinitialization}, are
reproduced well in the GREM. The existence of many layers causing continuous
transitions is very important for the two natures. Results of experiments in
other glassy materials such as polymers, supercooled glycerol and orientational
glasses, which are contrast to those in spin glasses, are interpreted well by
the Single-layer Random Energy Model.

</DOC>
<DOC>
<DOCNO> 99902 </DOCNO>
Loops of Lagrangian submanifolds and pseudoholomorphic discs


  The main theorem of this paper asserts that the inclusion of the space of
projective Lagrangian planes into the space of Lagrangian submanifolds of
complex projective space induces an injective homomorphism of fundamental
groups. We introduce three invariants of exact loops of Lagrangian submanifolds
that are modelled on invariants introduced by Polterovich for loops of
Hamiltonian symplectomorphisms. One of these is the minimal Hofer length in a
given Hamiltonian isotopy class. We determine the exact values of these
invariants for loops of projective Lagrangian planes. The proof uses the Gromov
invariants of an associated symplectic fibration over the 2-disc with a
Lagrangian subbundle over the boundary.

</DOC>
<DOC>
<DOCNO> 8436 </DOCNO>
No quasi-long-range order in strongly disordered vortex glasses: a


  The paper contains a rigorous proof of the absence of quasi-long-range order
in the random-field O(N) model for strong disorder in the space of an arbitrary
dimensionality. This result implies that quasi-long-range order inherent to the
Bragg glass phase of the vortex system in disordered superconductors is absent
as the disorder or external magnetic field is strong.

</DOC>
<DOC>
<DOCNO> 85581 </DOCNO>
Gravitomagnetism and Relative Observer Clock Effects


  The gravitomagnetic clock effect and the Sagnac effect for circularly
rotating orbits in stationary axisymmetric spacetimes are studied from a
relative observer point of view, clarifying their relationships and the roles
played by special observer families. In particular Semer\'ak's recent
characterization of extremely accelerated observers in terms of the two-clock
clock effect is shown to be complemented by a similarly special property of the
single-clock clock effect.

</DOC>
<DOC>
<DOCNO> 39921 </DOCNO>
Higgs Boson Decays to CP-odd Scalars at the Tevatron and Beyond


  In extended Higgs models, the Higgs boson may decay into a pair of light
CP-odd scalars, with distinctive collider signatures. We study the ensuing
Higgs signals at the upgraded Tevatron, considering the subsequent decays of
the scalars into pairs of gluons or photons. For CP-odd scalars lighter than a
few GeV, the Higgs boson manifests itself as a diphoton resonance and can be
discovered up to masses of a few hundred GeV. For heavier CP-odd scalars the
reach extends at most up to $M_h\sim 120$ GeV. We also discuss the capabilities
of the LHC and lepton colliders in these channels.

</DOC>
<DOC>
<DOCNO> 100599 </DOCNO>
On some mathematical construction of many-dimensional cosmos


  It is shown that classical Clifford algebras are group algebras of cyclic
subgroups of arrowy rermutations. It is established that Euclidean 3-space,
Pauli and Dirac algebras and groups of global guage transformations are
corollary from the geometry of 8-dimensional vacuum and 9-dimensional cosmos.

</DOC>
<DOC>
<DOCNO> 39680 </DOCNO>
Muon Collider/Neutrino Factory: Status and Prospects


  During the 1990s an international collaboration has been studying the
possibility of constructing and operating a high-energy high-luminosity
$\mu^+\mu^-$ collider. Such a machine could be the approach of choice to extend
our discovery reach beyond that of the LHC. More recently, a growing
collaboration is exploring the potential of a stored-muon-beam "neutrino
factory" to elucidate neutrino oscillations. A neutrino factory could be an
attractive stepping-stone to a muon collider. Its construction, possibly
feasible within the coming decade, could have substantial impact on neutrino
physics.

</DOC>
<DOC>
<DOCNO> 123117 </DOCNO>
A cloudy model for the Circumnuclear Disk in the Galactic Centre


  We present a first attempt to construct an analytic model for a clumped gas
and dust disk and apply it to the Galactic Centre. The clumps are described as
isothermal spheres partially ionized by the external UV radiation field. The
disk structure formed by the clouds is described as a quasi standard continuous
accretion disk using adequately averaged parameters of the discrete cloud
model. The viscosity in the Circumnuclear Disk is due to partially inelastic
cloud-cloud collisions. We find two different solutions for the set of
equations corresponding to two stable cloud regimes: (i) the observed molecular
clouds and (ii) much lighter and smaller clouds which correspond to the
stripped cores of the observed clouds. It is shown that the resulting physical
characteristics of the heavy clouds and the disk are in very good agreement
with all comparable observations at multiple wavelengths. A mass accretion rate
of approx. 10^-4 M_solar/yr for the isolated Circumnuclear Disk is inferred. We
propose that the Circumnuclear Disk has a much longer lifetime (approx. 10^7
yr) than previously assumed.

</DOC>
<DOC>
<DOCNO> 11012 </DOCNO>
Kondo Temperature for the Two-Channel Kondo Models of Tunneling Centers


  The possibility for a two-channel Kondo ($2CK$) non Fermi liquid state to
appear in a metal as a result of the interaction between electrons and movable
structural defects is revisited. As usual, the defect is modeled by a heavy
particle moving in an almost symmetric double-well potential (DWP). Taking into
account only the two lowest states in DWP is known to lead to a Kondo-like
Hamiltonian with rather low Kondo temperature, $T_K$. We prove that, in
contrast to previous believes, the contribution of higher excited states in DWP
does not enhance $T_K$. On the contrary, $T_K$ is reduced by three orders of
magnitude as compared with the two-level model: the prefactor in $T_K$ is
determined by the spacing between the second and the third levels in DWP rather
than by the electron Fermi energy. Moreover, $T_K$, turns out to be
parametrically smaller than the splitting between the two lowest levels.
Therefore, there is no microscopic model of movable defects which may justify
non-Fermi liquid $2CK$ phenomenology.

</DOC>
<DOC>
<DOCNO> 9632 </DOCNO>
Finite-temperature resistive transition in the two-dimensional XY gauge


  We investigate numerically the resistive transition in the two-dimensional XY
gauge glass model. The resistively-shunted junction dynamics subject to the
fluctuating twist boundary condition is used and the linear resistances in the
absence of an external current at various system sizes are computed. Through
the use of the standard finite-size scaling method, the finite temperature
resistive transition is found at $k_BT_c = 0.22(2)$ (in units of the Josephson
coupling strength) with dynamic critical exponent $z = 2.0(1)$ and the static
exponent $\nu = 1.2(2)$, in contrast to widely believed expectation of the
zero-temperature transition. Comparisons with existing experiments and
simulations are also made.

</DOC>
<DOC>
<DOCNO> 152618 </DOCNO>
General Two-Dimensional Supergravity from Poisson Superalgebras


  We provide the geometric actions for most general N=1 supergravity in two
spacetime dimensions. Our construction implies an extension to arbitrary N.
This provides a supersymmetrization of any generalized dilaton gravity theory
or of any theory with an action being an (essentially) arbitrary function of
curvature and torsion.
  Technically we proceed as follows: The bosonic part of any of these theories
may be characterized by a generically nonlinear Poisson bracket on a
three-dimensional target space. In analogy to a given ordinary Lie algebra, we
derive all possible N=1 extensions of any of the given Poisson (or W-)
algebras. Using the concept of graded Poisson Sigma Models, any extension of
the algebra yields a possible supergravity extension of the original theory,
local Lorentz and super-diffeomorphism invariance follow by construction. Our
procedure automatically restricts the fermionic extension to the minimal one;
thus local supersymmetry is realized on-shell. By avoiding a superfield
approach we are also able to circumvent in this way the introduction of
constraints and their solution. For many well-known dilaton theories different
supergravity extensions are derived. In generic cases their field equations are
solved explicitly.

</DOC>
<DOC>
<DOCNO> 84992 </DOCNO>
Nonlinear r-modes in Rapidly Rotating Relativistic Stars


  The r-mode instability in rotating relativistic stars has been shown recently
to have important astrophysical implications (including the emission of
detectable gravitational radiation, the explanation of the initial spins of
young neutron stars and the spin-distribution of millisecond pulsars and the
explanation of one type of gamma-ray bursts), provided that r-modes are not
saturated at low amplitudes by nonlinear effects or by dissipative mechanisms.
Here, we present the first study of nonlinear r-modes in isentropic, rapidly
rotating relativistic stars, via 3-D general-relativistic hydrodynamical
evolutions. Our numerical simulations show that (1) on dynamical timescales,
there is no strong nonlinear coupling of r-modes to other modes at amplitudes
of order one -- unless nonlinear saturation occurs on longer timescales, the
maximum r-mode amplitude is of order unity (i.e., the velocity perturbation is
of the same order as the rotational velocity at the equator). An absolute upper
limit on the amplitude (relevant, perhaps, for the most rapidly rotating stars)
is set by causality. (2) r-modes and inertial modes in isentropic stars are
predominantly discrete modes and possible associated continuous parts were not
identified in our simulations. (3) In addition, the kinematical drift
associated with r-modes, recently found by Rezzolla, Lamb and Shapiro (2000),
appears to be present in our simulations, but an unambiguous confirmation
requires more precise initial data. We discuss the implications of our findings
for the detectability of gravitational waves from the r-mode instability.

</DOC>
<DOC>
<DOCNO> 151226 </DOCNO>
Anisotropic Four-Dimensional NS-NS String Cosmology


  An anisotropic (Bianchi type I) cosmology is considered in the
four-dimensional NS-NS sector of low-energy effective string theory coupled to
a dilaton and an axion-like $H$-field within a de Sitter-Einstein frame
background. The time evolution of this Universe is discussed in both the
Einstein and string frames.

</DOC>
<DOC>
<DOCNO> 13583 </DOCNO>
Parallel Sparse Matrix Multiplication for Linear Scaling Electronic


  Linear-scaling electronic-structure techniques, also called O(N) techniques,
rely heavily on the multiplication of sparse matrices, where the sparsity
arises from spatial cut-offs. In order to treat very large systems, the
calculations must be run on parallel computers. We analyse the problem of
parallelising the multiplication of sparse matrices with the sparsity pattern
required by linear-scaling techniques. We show that the management of
inter-node communications and the effective use of on-node cache are helped by
organising the atoms into compact groups. We also discuss how to identify a key
part of the code called the `multiplication kernel', which is repeatedly
invoked to build up the matrix product, and explicit code is presented for this
kernel. Numerical tests of the resulting multiplication code are reported for
cases of practical interest, and it is shown that their scaling properties for
systems containing up to 20,000 atoms on machines having up to 512 processors
are excellent. The tests also show that the cpu efficiency of our code is
satisfactory.

</DOC>
<DOC>
<DOCNO> 70805 </DOCNO>
Coherent Exclusive Exponentiation for Precision Monte Carlo Calculations


  We present the new Coherent Exclusive Exponentiation (CEEX), in comparison to
the older Exclusive Exponentiation (EEX) and the semi-analytical Inclusive
Exponentiation (IEX), for the process e+e- -> f-bar f + n(gamma),
f=mu,tau,d,u,s,c,b, with validity for centre of mass energies from tau lepton
threshold to 1 TeV. We analyse 2f numerical results at the Z-peak, 189 GeV and
500 GeV. We also present precision calculations of the signal processes e+e- ->
4f in which the double resonant W+W- intermediate state occurs using our
YFSWW3-1.14 MC. Sample 4f Monte Carlo data are explicitly illustrated in
comparison to the literature at LEP2 energies. These comparisons show that a TU
for the signal process cross section of 0.4 percent is valid for the LEP2 200
GeV energy. LC energy results are also shown.

</DOC>
<DOC>
<DOCNO> 118581 </DOCNO>
A Direct Distance to the LMC Cepheid HV 12198 from the Infrared Surface


  We report on a first application of the infrared surface brightness technique
on a Cepheid in the Large Magellanic Cloud, the variable HV 12198 in the young
globular cluster NGC 1866. From this one star, we determine a distance modulus
of 18.42 +- 0.10 (random and systematic uncertainty) to the cluster. When the
results on further member Cepheids in NGC 1866 become available, we expect to
derive the distance to the LMC with a +- 3-4 percent accuracy, including
systematic errors, from this technique.

</DOC>
<DOC>
<DOCNO> 67843 </DOCNO>
Resonant Amplification of Gauge Fields in Expanding Universe


  We investigate the possibility that gauge fluctuations are amplified in an
expanding universe by parametric resonance, during the oscillatory regime of a
scalar field to which they are coupled. We investigate the couplings of gauge
fields to a charged scalar field and to an axion. For both couplings, gauge
field fluctuations undergo exponential instabilities. We discuss how the
presence of other charges or currents may counteract the resonance, but we
argue that in some cases the resonance will persist and that hence this
mechanism could have some relevance for the problem of large scale primordial
magnetic fields.

</DOC>
<DOC>
<DOCNO> 152300 </DOCNO>
Alternative N=2 Supergravity in Five Dimensions with Singularities


  We present an alternative N=2 supergravity multiplet coupled to n copies of
vector multiplets and n' copies of hypermultiplets in five dimensions. Our
supergravity multiplet contains a single antisymmetric tensor and a dilaton,
which are natural Neveu-Schwarz massless fields in superstring theory. The
absence of the explicit Chern-Simons terms in our lagrangian deletes the
non-trivial constraints on the couplings of vector multiplets in the
conventional formulation. The scalars in the vector multiplets form the
sigma-model for the coset SO(n,1) / SO(n), like those in the vector multiplets
coupled to N=1 supergravity in nine dimensions, while the scalars in the
hypermultiplets form that for the quaternionic Kahler manifold Sp(n',1) /
Sp(n') X Sp(1). We also perform the gauging of the SO(2) subgroup of the Sp(1)
= SL(2,R) automorphism group of N=2 supersymmetry. Our result is also
generalized to singular 5D space-time as in the conventional formulation, as a
preliminary for supersymmetric Randall-Sundrum brane world scenario.

</DOC>
<DOC>
<DOCNO> 13288 </DOCNO>
Pathologies of the large-N limit for RP^{N-1}, CP^{N-1}, QP^{N-1} and


  We compute the phase diagram in the N\to\infty limit for lattice RP^{N-1},
CP^{N-1} and QP^{N-1} sigma-models with the quartic action, and more generally
for mixed isovector/isotensor models. We show that the N=\infty limit exhibits
phase transitions that are forbidden for any finite N. We clarify the origin of
these pathologies by examining the exact solution of the one-dimensional model:
we find that there are complex zeros of the partition function that tend to the
real axis as N\to\infty. We conjecture the correct phase diagram for finite N
as a function of the spatial dimension d. Along the way, we prove some new
correlation inequalities for a class of N-component sigma-models, and we obtain
some new results concerning the complex zeros of confluent hypergeometric
functions.

</DOC>
<DOC>
<DOCNO> 72148 </DOCNO>
Traveling Faster than the Speed of Light in Non-Commutative Geometry


  We study various dynamical aspects of solitons in non-commutative gauge
theories and find surprising results. Among them is the observation that the
solitons can travel faster than the speed of light for arbitrarily long
distances.

</DOC>
<DOC>
<DOCNO> 13003 </DOCNO>
Decoherence in a superconducting ring


  A superconducting ring has different sectors of states corresponding to
different values of the trapped magnetic flux; this multitude of states can be
used for quantum information storage. If a current supporting a nonzero flux is
set up in the ring, fluctuations of electromagnetic field will be able to
``detect'' that current and thus cause a loss of quantum coherence. We estimate
the decoherence exponent for a ring of a round type-II wire and find that it
contains a macroscopic suppression factor $(\delta / R_{1})^{2}$, where $R_{1}$
is the radius of the wire, and $\delta$ is the London penetration depth. We
present some encouraging numerical estimates based on this result.

</DOC>
<DOC>
<DOCNO> 120455 </DOCNO>
To Probe a Black Hole


  We show how an idealized high-frequency VLBI can probe the metric of nearby
supermassive black holes. No quantitative assumptions about plasma dynamics are
used in the suggested diagnostic, which is based on strong-field lensing.

</DOC>
<DOC>
<DOCNO> 70181 </DOCNO>
Comment on ``Linking solar and long baseline terrestrial neutrino


  We comment on ``Linking solar and long baseline terrestrial neutrino
experiments''

</DOC>
<DOC>
<DOCNO> 119672 </DOCNO>
Magnetic Field Decay in Neutron Stars. Analysis of General Relativistic


  An analysis of the role of general relativistic effects on the decay of
neutron star's magnetic field is presented. At first, a generalized induction
equation on an arbitrary static background geometry has been derived and,
secondly, by a combination of analytical and numerical techniques, a comparison
of the time scales for the decay of an initial dipole magnetic field in flat
and curved spacetime is discussed. For the case of very simple neutron star
models, rotation not accounted for and in the absence of cooling effects, we
find that the inclusion of general relativistic effects result, on the average,
in an enlargement of the decay time of the field in comparison to the flat
spacetime case. Via numerical techniques we show that, the enlargement factor
depends upon the dimensionless compactness ratio ${\epsilon}={2GM \over
c^{2}R}$, and for ${\epsilon}$ in the range $(0.3~,~0.5)$, corresponding to
compactness ratio of realistic neutron star models, this factor is between 1.2
to 1.3. The present analysis shows that general relativistic effects on the
magnetic field decay ought to be examined more carefully than hitherto. A brief
discussion of our findings on the impact of neutron stars physics is also
presented.

</DOC>
<DOC>
<DOCNO> 13820 </DOCNO>
A pseudo-spectral approach to inverse problems in interface dynamics


  An improved scheme for computing coupling parameters of the
Kardar-Parisi-Zhang equation from a collection of successive interface
profiles, is presented. The approach hinges on a spectral representation of
this equation. An appropriate discretization based on a Fourier representation,
is discussed as a by-product of the above scheme. Our method is first tested on
profiles generated by a one-dimensional Kardar-Parisi-Zhang equation where it
is shown to reproduce the input parameters very accurately. When applied to
microscopic models of growth, it provides the values of the coupling parameters
associated with the corresponding continuum equations. This technique favorably
compares with previous methods based on real space schemes.

</DOC>
<DOC>
<DOCNO> 99773 </DOCNO>
Monodromy at Infinity and the Weights of Cohomology


  We show that for a polynomial map, the size of the Jordan blocks for the
eigenvalue 1 of the monodromy at infinity is bounded by the multiplicity of the
reduced divisor at infinity of a good compactification of a general fiber. The
existence of such Jordan blocks is related to global invariant cycles of the
graded pieces of the weight filtration. These imply some applications to period
integrals. We also show that such a Jordan block of size greater than 1 for the
graded pieces of the weight filtration is the restriction of a strictly larger
Jordan block for the total cohomology group. If there are no singularities at
infinity, we have a more precise statement on the monodromy.

</DOC>
<DOC>
<DOCNO> 67687 </DOCNO>
Bose-Einstein Correlations in e+e- -> W+W- at a Linear Collider


  We show that the most popular method to simulate Bose-Einstein (BE)
interference effects predicts negligible correlations between identical pions
originating from the hadronic decay of different W's produced in e+e- -> W+W-
-> 4 jets at typical linear collider energies.

</DOC>
<DOC>
<DOCNO> 68354 </DOCNO>
Inclusive jet production on the nucleus in the perturbative QCD with


  Using the recently found hA amplitude, single and double inclusive jet
production rates on the nucleus are studied in the perturbative QCD with
$N_c\to\infty$. Jet multiplicities are found to grow with $A$ and energy as
$A^{2/9}s^\Delta$ where $\Delta$ is the BFKL intercept. Long range correlations
are found to behave as $A^{4/9}s^{2\Delta}$ and change from negative to
positive at a certain high energy.

</DOC>
<DOC>
<DOCNO> 71545 </DOCNO>
Physics of mirror photons


  The physics of kinetic mixing between ordinary and mirror photons is
discussed. An important role is played by four linear combinations we dub the
physical photon, the sterile photon, the physical mirror photon, and the
sterile mirror photon. Because of the mass degeneracy between the two gauge
bosons, quantum coherence effects are important. The physical photon becomes a
certain coherent superposition of the bare ordinary photon and the bare mirror
photon. Similarly, the physical mirror photon is another, but {\it not
orthogonal}, coherent superposition. We discuss the physics of the interaction
between physical mirror photons and ordinary matter. Observational signatures
for some hybrid ordinary/mirror binary astrophysical systems are qualitatively
discussed. We show that a small amount of ordinary matter at the center of a
mirror star may make the mirror star observable. We speculate that the recently
reported halo white dwarfs might actually be mirror halo stars.

</DOC>
<DOC>
<DOCNO> 100653 </DOCNO>
Equivariant K-groups of spheres with actions of involutions


  We calculate the R(G)-algebra structure on the reduced equivariant K-groups
of two-dimensional spheres on which a compact Lie group G acts as involutions.
In particular, the reduced equivariant K-groups are trivial if G is abelian,
which shows that the previous Y. Yang's calculation in [Yan95] is not true.

</DOC>
<DOC>
<DOCNO> 99534 </DOCNO>
Algebraic duality for partially ordered sets


  For an arbitrary partially ordered set $P$ its {\em dual} $P^*$ is built as
the collection of all monotone mappings $P\to\2$ where $\2=\{0,1\}$ with $0<1$.
The set of mappings $P^*$ is proved to be a complete lattice with respect to
the pointwise partial order. The {\em second dual} $P^{**}$ is built as the
collection of all morphisms of complete lattices $P^*\to\2$ preserving
universal bounds. Then it is proved that the partially ordered sets $P$ and
$P^{**}$ are isomorphic.

</DOC>
<DOC>
<DOCNO> 84182 </DOCNO>
A Note on Solitons in Brane Worlds


  We obtain the zero mode effective action for gravitating objects in the bulk
of dilatonic domain walls. Without additional fields included in the bulk
action, the zero mode effective action reproduces the action in one lower
dimensions obtained through the ordinary Kaluza-Klein (KK) compactification,
only when the transverse (to the domain wall) component of the bulk metric does
not have non-trivial term depending on the domain wall worldvolume coordinates.
With additional fields included in the bulk action, non-trivial dependence of
the transverse metric component on the domain wall worldvolume coordinates
appears to be essential in reproducing the lower-dimensional action obtained
via the ordinary KK compactification. We find, in particular, that the
effective action for the charged (p+1)-brane in the domain wall bulk reproduces
the action for the p-brane in one lower dimensions.

</DOC>
<DOC>
<DOCNO> 85415 </DOCNO>
Scattering by Black Holes


  This is a chapter on Black-hole Scattering that was commissioned for an
Encyclopaedia on Scattering edited by Pike and Sabatier, to be published by
Academic Press. The chapter surveys wave propagation in black-hole spacetimes,
diffraction effects in wave scattering, resonances, quasinormal modes and
related topics.

</DOC>
<DOC>
<DOCNO> 122348 </DOCNO>
The Be/X-ray transient 4U 0115+63/V635 Cas I. A consistent model


  We present photometry and high SNR spectroscopy in the classification region
of V635 Cas, the optical counterpart to the transient X-ray pulsator 4U
0115+63, taken at a time when the circumstellar envelope had disappeared. V635
Cas is classified as a B0.2Ve star at a distance of 7-8 kpc. We use the
physical parameters derived from these observations and the orbit derived from
X-ray observations to elaborate a model of the system based on the theory of
decretion discs around Be stars. We show that the disc surrounding the Be star
must be truncated by the tidal/resonant interaction with the neutron star and
cannot be in a steady state. This explains many of the observed properties of
4U 0115+63. In particular, because of this effect, under normal circumstances,
the neutron star cannot accrete from the disc, which explains the lack of
regular Type I outbursts from the source.

</DOC>
<DOC>
<DOCNO> 121412 </DOCNO>
Extragalactic radio sources with hybrid morphology: implications for the


  We provide observational and theoretical perspectives on the currently much
debated issue of the Fanaroff-Riley (FR) morphological dichotomy of
extragalactic radio sources. In this context we introduce a new, albeit rare,
class of double radio sources in which the two lobes exhibit clearly different
FR morphologies. It is argued that such `HYbrid MOrphology Radio Sources', or
HYMORS, could be used to effectively constrain the theoretical mechanisms
proposed for the FR dichotomy. Basically, the existence of HYMORS supports
explanations for the FR dichotomy based upon jet interaction with the medium
external to the central engine, and appears quite difficult to reconcile with
the class of explanations that posit fundamental differences in the central
engine, such as black hole spin or jet composition, to be responsible for the
two FR classes of double radio sources.

</DOC>
<DOC>
<DOCNO> 151408 </DOCNO>
The D0-brane metric in N = 2 sigma models


  We investigate the physical metric seen by a D0-brane probe in the background
geometry of an N=2 sigma model. The metric is evaluated by calculating the
Zamolodchikov metric for the disc two point function of the boundary operators
corresponding to the displacement of the D0-brane boundary. At two loop order
we show that the D0 metric receives an $R^2$ contribution.

</DOC>
<DOC>
<DOCNO> 9623 </DOCNO>
Calculating response functions in time domain with non-orthonormal basis


  We extend the recently proposed order-N algorithms (cond-mat/9703224) for
calculating linear- and nonlinear-response functions in time domain to the
systems described by nonorthonormal basis sets.

</DOC>
<DOC>
<DOCNO> 70752 </DOCNO>
Filling up the Two-Body Partial Decay Width of P-Wave Charmonia with the


  The importance of the color octet component in P-wave charmonia is discussed
in the context of exclusive decay processes. It is vital to include this
contribution already at the level of the two-body decay channels. The \pi \pi
and proton-antiproton channels are used as examples.

</DOC>
<DOC>
<DOCNO> 99300 </DOCNO>
Failure of Brown representability in derived categories


  Let T be a triangulated category with coproducts, C the full subcategory of
compact objects in T. If T is the homotopy category of spectra, Adams proved
the following in [Adams71]: All contravariant homological functors C --> Ab are
the restrictions of representable functors on T, and all natural
transformations are the restrictions of morphisms in T.
  It has been something of a mystery, to what extent this generalises to other
triangulated categories. In [Neeman97], it was proved that Adams' theorem
remains true as long as C is countable, but can fail in general. The failure
exhibited was that there can be natural transformations not arising from maps
in T. A puzzling open problem remained: Is every homological functor the
restriction of a representable functor on T? In a recent paper, Beligiannis
made some progress. But in this article, we settle the problem. The answer is
no. There are examples of derived categories T = D(R) of rings, and
contravariant homological functors C --> Ab which are not restrictions of
representables.

</DOC>
<DOC>
<DOCNO> 10098 </DOCNO>
Restoration of Macroscopic Isotropy on $(d+1)$-Simplex Fractal Conductor


  Restoration of macroscopic isotropy has been investigated in (d+1)-simplex
fractal conductor networks via exact real space renormalization group
transformations. Using some theorems of fixed point theory, it has been shown
very rigoroursly that the macroscopic conductivity becomes isotropic for large
scales and anisotropy vanishes with a scaling exponent which is computed
exactly for arbitrary values of d and decimation numbers b=2,3,4 and
 5.

</DOC>
<DOC>
<DOCNO> 70616 </DOCNO>
Towards a refined cosmic concordance model: joint 11-parameter


  We present a method for calculating large numbers of power spectra C_l and
P(k) that accelerates CMBfast by a factor around 10^3 without appreciable loss
of accuracy, then apply it to constrain 11 cosmological parameters from current
Cosmic Microwave Background (CMB) and Large Scale Structure (LSS) data. While
the CMB alone still suffers from several degeneracies, allowing, e.g., closed
models with strong tilt and tensor contributions, the shape of the real space
power spectrum of galaxies from the IRAS Point Source Catalogue Redshift (PSCz)
survey breaks these degeneracies and helps place strong constraints on most
parameters. At 95% confidence, the combined CMB and LSS data imply a baryon
density 0.020 < omega_b < 0.037, dark matter density 0.10 < omega_d < 0.32 with
a neutrino fraction f_nu < 38%, vacuum density Omega_Lambda < 0.76, curvature
-0.19 < Omega_k < 0.10, scalar tilt 0.86 < n_s < 1.16 and reionization optical
depth tau < 0.44. These joint constraints are quite robust, changing little
when we impose priors on the Hubble parameter, tilt, flatness, gravity waves or
reionization. Adding nucleosynthesis and neutrino priors on the other hand
tightens parameters considerably, requiring Omega_Lambda > 0.49 and a red-tilt.
  The analysis allows a number of consistency tests to be made, all of which
pass. At the 95% level, the flat scalar ``concordance model'' with
Omega_Lambda=0.62, omega_d=0.13, omega_b=0.02, f_nu~0, n_s=0.9, tau=0.1, h=0.63
is consistent with external constraints. The inferred PSCz bias b~1.2 agrees
with the value estimated independently from redshift space distortions. The
inferred cosmological constant value agrees with the one independently derived
from SN 1a studies. Cosmology seems to be on the right track.

</DOC>
<DOC>
<DOCNO> 71499 </DOCNO>
Gravity in Warped Compactifications and the Holographic Stress Tensor


  We study gravitational aspects of Brane-World scenarios. We show that the
bulk Einstein equations together with the junction condition imply that the
induced metric on the brane satisfies the full non-linear Einstein equations
with a specific effective stress energy tensor. This result holds for any value
of the bulk cosmological constant. The analysis is done by either placing the
brane close to infinity or by considering the local geometry near the brane. In
the case that the bulk spacetime is asymptotically AdS, we show that the
effective stress energy tensor is equal to the sum of the stress energy tensor
of matter localized on the brane and of the holographic stress energy tensor
appearing in the AdS/CFT duality. In addition, there are specific
higher-curvature corrections to Einstein's equations. We analyze in detail the
case of asymptotically flat spacetime. We obtain asymptotic solutions of
Einstein's equations and show that the effective Newton's constant on the brane
depends on the position of the brane.

</DOC>
<DOC>
<DOCNO> 70767 </DOCNO>
Soft gluon cascades and BFKL equation


  In this paper we deal with high energy scattering in the Regge limit. In the
leading logarithmic approximation of perturbative QCD, we show that BFKL
equation and its generalizations can be simply recovered as an evolution
equation for gluon density in soft gluons cascade. Comparison is performed with
respect to QED case, and the running of the coupling is discussed.

</DOC>
<DOC>
<DOCNO> 12315 </DOCNO>
A comparison of Monte-Carlo simulations using RESTRAX and McSTAS with


  Monte-Carlo simulations of a focusing supermirror guide after the
monochromator on the IN14 cold neutron three-axis spectrometer, I.L.L. were
carried out using the instrument simulation programs RESTRAX and McSTAS. The
simulations were compared to experiment to check their accuracy. Comparisons of
the flux ratios over both a 100 mm2 and a 1600 mm2 area at the sample position
compare well, and there is very close agreement between simulation and
experiment for the energy spread of the incident beam.

</DOC>
<DOC>
<DOCNO> 71495 </DOCNO>
Three-Body Decays of Top and Bottom Squarks


  We investigate the decays of third generation scalar quarks in the Minimal
Supersymmetric extension of the Standard Model, focusing on the three-body
modes. We calculate the partial widths of the decays of heavier top and bottom
squarks into the lighter ones and a fermion pair [through virtual vector boson,
Higgs boson or gaugino exchanges] and the partial widths of the three-body
decays of both top squarks into bottom quarks and a pair of fermion and scalar
fermion [we consider the case of lighter $\tilde{\tau}$ or $\tilde{b}$ states]
and into a bottom quark, the lightest neutralino and a $W$ or a charged Higgs
boson $H^\pm$. Some of these decay modes are shown to have substantial
branching ratios in some areas of the parameter space.

</DOC>
<DOC>
<DOCNO> 102156 </DOCNO>
Apollonian Circle Packings: Geometry and Group Theory II.


  A Descartes configuration is a set of four mutually tangent circles in the
Riemann sphere, having disjoint interiors. Part I showed there is a natural
group action on Descartes quadruples by a group $Iso^\uparrow(Q_2)$ which acts
linearly on Descartes quadruples given in curvature-center coordinates. It
contains a discrete subgroup, the Apollonian group, which consists of $4 \times
4$ integer matrices, which leaves packings invariant and acts transitively on
their (unordered) Descartes configurations. The Apollonian group is a
hyperbolic Coxeter group. In this paper define a larger group inside $GL(4,
\zz)$ generated by the Apollonian group $\sA$ and its transpose $\sA^T$, which
we call the {\em super-Apollonian group.} The super-Apollonian group is shown
to be a hyperbolic Coxeter group. We study an object that we call the
``integral Apollonian super-gasket'', which consists of all (ordered) primitive
integer Descartes configurations, i.e. four tangent circles with integer
curvatures, each of whose curvature$\times$center is a Gaussian integer, such
that the integer curvatures of circles in these quadruples have no nontrivial
common divisor. The group of conformal transformations that preserve the
integer Apollonian super-gasket is transitive on its members. Geometrically the
super-Apollonian group acts nearly transitively on the integral Apollonian
super-gasket, having 8 orbits. We use this fact to show that the
super-Apollonian group is a subgroup of index 2 in the group of integral
automorphs of the Descartes quadratic form.

</DOC>
<DOC>
<DOCNO> 9916 </DOCNO>
Microwave Induced Instability Observed in BSCCO 2212 in a Static


  We have measured the microwave dissipation at 10 GHz through the imaginary
part of the susceptibility, $\chi^"$, in a BSCCO 2212 single crystal in an
external static magnetic field $H$ parallel to the c-axis at various fixed
temperatures. The characteristics of $\chi^"(H)$ exhibit a sharp step at a
field $H_{step}$ which strongly depends on the amplitude of the microwave
excitation $h_{ac}$. The characteristics of $h_{ac}$ vs. $H_{step}$,
qualitatively reveal the behavior expected for the magnetic field dependence of
Josephson coupling.

</DOC>
<DOC>
<DOCNO> 71838 </DOCNO>
Large Neutrino Mixing from Renormalization Group Evolution


  The renormalization group evolution equation for two neutrino mixing is known
to exhibit nontrivial fixed point structure corresponding to maximal mixing at
the weak scale. The presence of the fixed point provides a natural explanation
of the observed maximal mixing of $\nu_{\mu}-\nu_{\tau}$ if the $\nu_{\mu}$ and
$\nu_{\tau}$ are assumed to be quasi-degenerate at the seesaw scale without
constraining on the mixing angles at that scale. In particular, it allows them
to be similar to the quark mixings as in generic grand unified theories. We
discuss implementation of this program in the case of MSSM and find that the
predicted mixing remains stable and close to its maximal value, for all
energies below the $O$(TeV) SUSY scale. We also discuss how a particular
realization of this idea can be tested in neutrinoless double beta decay
experiments.

</DOC>
<DOC>
<DOCNO> 70962 </DOCNO>
New Higgs signals from vector boson fusion in R-parity violating


  We investigate signals of the lightest neutral Higgs in an R-parity violating
supersymmetric model through the vector boson fusion mechanism. Assuming that
R-parity is violated through lepton number, and locating regions in the
parameter space where decays of such a neutral scalar into a pair of lightest
neutralinos can be significant, we proceed to calculate the event rates for
final states arising from decays of the neutralinos through both $\lambda$-and
$\lambda'$-type interactions. Regions of the parameter space where each of
these types of interactions can lead to detectable events are identified. The
possibilities where such signals can be faked by other superparticles (squarks,
gluinos, charginos and neutralinos) are also investigated. It is found that
over a sizable region, one can obtain distinguishable signals of an
intermediate mass neutral scalar from a study of the suggested final states at
the Large Hadron Collider.

</DOC>
<DOC>
<DOCNO> 119414 </DOCNO>
FUSE Observations of O VI Absorption in the Galactic Halo


  Far-ultraviolet spectra of 11 AGNs observed by FUSE are analyzed to obtain
measures of O VI 1031.93 A absorption occurring over very long paths through
Milky Way halo gas. Strong O VI absorption is detected along 10 of 11 sight
lines. Values of log [N(O VI) sin|b|] range from 13.80 to 14.64 with a median
value of 14.21. The observations reveal the existence of a widespread but
irregular distribution of O VI in the Milky Way halo. Combined with estimates
of the O VI mid-plane density, n0 = 2x10^(-8) cm^(-3), from the Copernicus
satellite, the FUSE observations imply an O VI exponential scale height of
2.7+/-0.4 kpc. We find that N(C IV)/N(O VI) ranges from 0.15 in the disk to 0.6
along four extragalactic sight lines. The changing ionization state of the gas
from the disk to the halo is consistent with a systematic decrease in the scale
heights of Si IV, C IV, N V, to O VI from ~5.1 to ~2.7 kpc. While conductive
heating models can account for the highly ionized atoms at low |z|, a
combination of models (and processes) appears to be required to explain the
highly ionized atoms found in the halo. The greater scale heights of Si IV and
C IV compared to O VI suggest that some of the Si IV and C IV in the halo is
produced in turbulent mixing layers or by photoionization by hot halo stars or
the extragalactic background.

</DOC>
<DOC>
<DOCNO> 9768 </DOCNO>
Theory of the solid-state physics on the turn: II. Importance of the


  The orbital and spin moment of the Ni2+ ion in NiO has been calculated at 0 K
to be 0.54mB and 1.99 mB respectively. Such large orbital moment, more than 20%
of the total moment of 2.53 mB, proves the need for the ''unquenching'' of the
orbital moment in compounds containing 3d ions. It turns out that the
spin-orbit coupling is indispensable for description of magnetic and electronic
properties of 3d-ion compounds. These two findings, largely ignored at the
nowadays in-fashion solid-state thories, call for an advanced solid-state
physics theory.

</DOC>
<DOC>
<DOCNO> 83137 </DOCNO>
Automatic Classification of Text Databases through Query Probing


  Many text databases on the web are "hidden" behind search interfaces, and
their documents are only accessible through querying. Search engines typically
ignore the contents of such search-only databases. Recently, Yahoo-like
directories have started to manually organize these databases into categories
that users can browse to find these valuable resources. We propose a novel
strategy to automate the classification of search-only text databases. Our
technique starts by training a rule-based document classifier, and then uses
the classifier's rules to generate probing queries. The queries are sent to the
text databases, which are then classified based on the number of matches that
they produce for each query. We report some initial exploratory experiments
that show that our approach is promising to automatically characterize the
contents of text databases accessible on the web.

</DOC>
<DOC>
<DOCNO> 101613 </DOCNO>
Groupes p-divisibles, groupes finis et modules filtr\'es


  Let k be a perfect field of characteristic p>0. When p>2, Fontaine and
Laffaille have classified p-divisibles groups and finite flat p-groups over
the Witt vectors W(k) in terms of filtered modules. Still assuming p>2, we
extend these classifications over an arbitrary complete discrete valuation
ring A with unequal characteristic (0,p) and residue field k by using
"generalized" filtered modules. In particular, there is no restriction on the
ramification index. In the case k is included in \bar{F}_p (and p>2), we then
use this new classification to prove that any crystalline representation of
the Galois group of Frac(A) with Hodge-Tate weights in {0,1} contains as a
lattice the Tate module of a p-divisible group over A.

</DOC>
<DOC>
<DOCNO> 40550 </DOCNO>
The Power of Confidence Intervals


  We consider the power to reject false values of the parameter in Frequentist
methods for the calculation of confidence intervals. We connect the power with
the physical significance (reliability) of confidence intervals for a parameter
bounded to be non-negative. We show that the confidence intervals (upper
limits) obtained with a (biased) method that near the boundary has large power
in testing the parameter against larger alternatives and small power in testing
the parameter against smaller alternatives are physically more significant.
Considering the recently proposed methods with correct coverage, we show that
the physical significance of upper limits is smallest in the Unified Approach
and highest in the Maximum Likelihood Estimator method. We illustrate our
arguments in the specific cases of a bounded Gaussian distribution and a
Poisson distribution with known background.

</DOC>
<DOC>
<DOCNO> 121863 </DOCNO>
The Diffuse Interstellar Band at 8620 Ang: a good reddening tracer for


  We report about a suprisingly good correlation between the equivalent width
of the diffuse interstellar band (DIB) at 8620 Ang and the interstellar
reddening. Such a correlation offers bright prospects in using the 8620 Ang DIB
as a tracer of the exctinction through the Galaxy in the context of GAIA,
approved Cornerstone mission by ESA.

</DOC>
<DOC>
<DOCNO> 152331 </DOCNO>
Boundary Rings and N=2 Coset Models


  We investigate boundary states of N=2 coset models based on Grassmannians
Gr(n,n+k), and find that the underlying intersection geometry is given by the
fusion ring of U(n). This is isomorphic to the quantum cohomology ring of
Gr(n,n+k+1), and thus can be encoded in a ``boundary'' superpotential whose
critical points correspond to the boundary states. In this way the intersection
properties can be represented in terms of a soliton graph that forms a
generalized, Z_{n+k+1} symmetric McKay quiver. We investigate the spectrum of
bound states and find that the rational boundary CFT produces only a small
subset of the possible quiver representations.

</DOC>
<DOC>
<DOCNO> 99265 </DOCNO>
A Galois correspondence for II_1 factors and quantum groupoids


  We establish a Galois correspondence for finite quantum groupoid actions on
II_1 factors and show that every finite index and finite depth subfactor is an
intermediate subalgebra of a quantum groupoid crossed product. Moreover, any
such a subfactor is completely and canonically determined by a quantum groupoid
and its coideal *-subalgebra. This allows to express the bimodule category of a
subfactor in terms of the representation category of a corresponding quantum
groupoid and the principal graph as the Bratteli diagram of an inclusion of
certain C^*-algebras related to it.

</DOC>
<DOC>
<DOCNO> 123005 </DOCNO>
The cosmic microwave background bispectrum as a test of the physics of


  Why is non-Gaussianity interesting? One of generic predictions from
inflationary scenarios is that primordial fluctuations are exactly Gaussian in
linear order; however, the non-linearity in the inflation will produce weak
non-Gaussianity. Thus, measuring the non-Gaussianity in the cosmic microwave
background radiation anisotropy is a probe of the non-linear physics in the
very early universe. Since the angular three point function is zero for the
Gaussian field, it is sensitive to the non-Gaussianity. We predict its harmonic
transform counterpart, the angular {\it Bispectrum}, down to arcminutes angular
scales, including the full effect of the radiation transfer function. We find
that even the Planck experiment cannot detect the primary bispectrum from the
inflation, as long as the single field slow-roll inflation is right.
Non-linearities in the low redshift universe also produce the non-Gaussianity.
We find that secondary bispectra are detectable by both MAP and Planck
experiments. The secondary bispectra probe the non-linear physics of the
low-redshift universe. Although this could be a contaminant to the primary
signal, MAP and Planck experiments are found to be able to separate the primary
from secondary effects well. We present a tentative comparison of the primary
bispectrum to the published COBE 4 year bispectrum. The data put a weak
constraint on the parameter, and the constraint would become much tighter when
we use all modes available in the COBE data, and certainly forthcoming
satellite experiments. As a conclusion, the bispectrum is a key measure to
confirm or destroy the simple inflationary scenario in non-linear order that
seems quite successful in linear order.

</DOC>
<DOC>
<DOCNO> 118412 </DOCNO>
Pixel and Micro-lensing with NGST


  Within 8 years, the current microlensing surveys of M31 will provide several
hundred events affecting unresolved stars. They will thus allow a statistical
study of the dark matter in M31's halo. The NGST will resolve these stars and
constrain the mass of the corresponding lenses. In case of on-line alerts from
ground-based observations, real-time NGST follow-up with high signal-to-noise
ratio will provide further constraints on the lenses. In addition, high
resolution observations with NGST will complement XMM and the previous optical
data and thus enable a closer insight of X-ray binaries within M31 to be
obtained. The optimal instrumentation to achieve these scientific goals will be
discussed. Last, the study of the dark matter encompassed in the galaxy
clusters would be possible with high angular resolution observations on a large
field camera and would open a new field of research.

</DOC>
<DOC>
<DOCNO> 117900 </DOCNO>
A Close Separation Double Quasar Lensed by a Gas-Rich Galaxy


  In the course of a Cycle 8 snapshot survey, we have discovered that the
z=1.565 quasar HE 0512-3329 is a double with image separation 0.644", almost
certainly due to gravitational lensing. The two components differ in brightness
by only 0.4 magnitudes and a high signal-to-noise ground-based composite
optical spectrum shows no trace of any stellar features at zero redshift,
essentially ruling out the possibility that one of the two components is an
ordinary Galactic star. The optical spectrum shows strong absorption features
of MgII, MgI, FeII, FeI, and CaI, all at an identical intervening redshift of
z=0.9313, probably due to the lensing object. The strength of the MgII and the
presence of the other low ionization absorption features is strong evidence for
a damped Lyman alpha system, likely the disk of a spiral galaxy. Point spread
function fitting to remove the two quasar components from the STIS image leads
to a tentative detection of a third object which may be the nucleus of the
lensing galaxy. The brighter component is significantly redder than the
fainter, due to either differential extinction or microlensing.

</DOC>
<DOC>
<DOCNO> 12832 </DOCNO>
Slater Transition in the Pyrochlore Cd2Os2O7


  Cd2Os2O7 crystallizes in the pyrochlore structure and undergoes a
metal-insulator transition (MIT) near 226 K. We have characterized the MIT in
Cd2Os2O7 using X-ray diffraction, resistivity at ambient and high pressure,
specific heat, magnetization, thermopower, Hall coefficient, and thermal
conductivity. Both single crystals and polycrystalline material were examined.
The MIT is accompanied by no change in crystal symmetry and a change in unit
cell volume of less than 0.05%. The resistivity shows little temperature
dependence above 226 K, but increases by 3 orders of magnitude as the sample is
cooled to 4 K. The specific heat anomaly resembles a mean-field transition and
shows no hysteresis or latent heat. Cd2Os2O7 orders magnetically at the MIT.
The magnetization data is consistent with antiferromagnetic order, with a small
parasitic ferromagnetic component. The Hall and Seebeck coefficients are
consistent with a semiconducting gap opening at the Fermi energy at the MIT. We
have also performed electronic structure calculations on Cd2Os2O7. These
calculations indicate that Cd2Os2O7 is metallic, with a sharp peak in the
density of states at the Fermi energy. We intepret the data in terms of a
Slater transition. In this scenario, the MIT is produced by a doubling of the
unit cell due to the establishment of antiferromagnetic order. A Slater
transition-unlike a Mott transition-is predicted to be continuous, with a
semiconducting energy gap opening much like a BCS gap as the material is cooled
below $T_{MIT}$.

</DOC>
<DOC>
<DOCNO> 12806 </DOCNO>
Neutron scattering studies of Zn-doped La2-xSrxCuO4


  This paper reviews studies of the spatial modulation of spin in La2-xSrxCuO4
(LSCO) through neutron-scattering measurements of the elastic magnetic peaks,
with emphasis on Zn-doped LSCO. The elastic incommensurate magnetic peaks can
be categorized in two classes with respect to the temperature dependence.
Nd-doped LSCO, La2CuO4+y and LSCO with x ~ 1/8 exhibit an ordinary power law
behavior. On the other hand, Zn-doped LSCO and LSCO with x = 0.02-0.07 show an
exponential temperature dependence, and the correlation lengths stay short.
This discrepancy can be attributed to the difference in the mechanism of
pinning spin fluctuations. The former systems have pinning centers which is
coherent to the lattice. In the latter, however, pinning centers are randomly
scattered in the CuO2 planes, thus incoherent. The incoherent pinning model is
discussed with referring to recent mu-SR studies.

</DOC>
<DOC>
<DOCNO> 118502 </DOCNO>
The Properties of Molecular Hydrogen toward the Orion Belt Stars from


  Absorption features from the Lyman and Werner bands of interstellar molecular
hydrogen were recorded by the Interstellar Medium Absorption Profile
Spectrograph (IMAPS) at a wavelength resolving power R=80,000 in the spectra of
delta Ori and epsilon Ori. The objective was to find and study more examples of
an unusual phenomenon found for one of the velocity components of H2 in the
spectrum of zeta Ori by Jenkins & Peimbert (1997). Specifically, they detected
a gradual shift in velocity and broadening for features arising from
progressively higher rotational excitations J. This effect appears to be absent
in the spectra of both delta and epsilon Ori, which are only a few degrees away
in the sky from zeta Ori. The absence of atomic material at a large negative
velocity in the spectra of delta and epsilon Ori (and its presence in zeta Ori)
supports a proposal by Jenkins & Peimbert that the line of sight to zeta
intercepts a bow shock facing away from us, perhaps created by the collision of
wind-like material with some foreground obstruction. For both stars, the H2
absorption features are separated into two velocity components. Total H2 column
densities toward delta and epsilon Ori are 5.5e14 and 1.9e16 cm^-2,
respectively. The rotation temperatures of the molecules with J > 2 toward
epsilon Ori indicate that the gas is in the general vicinity of the stars that
emit UV fluxes capable of rotationally pumping the molecules. For the strongest
component of H2 toward delta Ori, the pumping rate is lower and consistent with
a general UV flux level in the plane of the Galaxy.

</DOC>
<DOC>
<DOCNO> 85086 </DOCNO>
Non-Abelian Stokes Theorems in Yang-Mills and Gravity Theories


  We recall the non-Abelian Stokes theorem for the Wilson loop in the
Yang-Mills theory and discuss its meaning. Then we move to `gravitational
Wilson loops', i.e. to holonomies in curved d=2,3,4 spaces and derive
non-Abelian Stokes theorems for these quantities as well, which are similar to
our formula in the Yang-Mills theory. In particular we derive an elegant
formula for the holonomy in the case of a constant-curvature background in
three dimensions and a formula for small-area loops in any number of
dimensions.

</DOC>
<DOC>
<DOCNO> 12478 </DOCNO>
Phase-separation of binary fluids in shear flow: a numerical study


  The phase-separation kinetics of binary fluids in shear flow is studied
numerically in the framework of the continuum convection-diffusion equation
based on a Ginzburg-Landau free energy. Simulations are carried out for
different temperatures both in d=2 and in d=3. Our results confirm the
qualitative picture put forward by the large-N limit equations studied in
\cite{noi}. In particular, the structure factor is characterized by the
presence of four peaks whose relative oscillations give rise to a periodic
modulation of the behavior of the rheological indicators and of the average
domains sizes. This peculiar pattern of the structure factor corresponds to the
presence of domains with two characteristic thicknesses whose relative
abundance changes with time.

</DOC>
<DOC>
<DOCNO> 152503 </DOCNO>
The Hopf Algebra Structure of Connes and Kreimer in Epstein-Glaser


  We show how the Hopf algebra structure of renormalization discovered by
Kreimer can be found in the Epstein-Glaser framework without using an analogue
of the forest formula of Zimmermann.

</DOC>
<DOC>
<DOCNO> 85578 </DOCNO>
Accelerating Photons with Gravitational Radiation


  The nature of superluminal photon propagation in the gravitational field
describing radiation from a time-dependent, isolated source (the Bondi-Sachs
metric) is considered in an effective theory which includes interactions which
violate the strong equivalence principle. Such interactions are, for example,
generated by vacuum polarisation in conventional QED in curved spacetime. The
relation of the resulting light-cone modifications to the Peeling Theorem for
the Bondi-Sachs spacetime is explained.

</DOC>
<DOC>
<DOCNO> 72104 </DOCNO>
Trilinear Neutral Gauge Boson Couplings in Effective Theories


  We list all the lowest dimension effective operators inducing off-shell
trilinear neutral gauge boson couplings Z-Z-Photon, Z-Photon-Photon, and ZZZ
within the effective Lagrangian approach, both in the linear and nonlinear
realizations of the SU(2)_{L} X U(1)_Y gauge symmetry. In the linear scenario
we find that these couplings can be generated only by dimension eight operators
necessarily including the Higgs boson field, whereas in the nonlinear case they
are induced by dimension six operators. We consider the impact of these
couplings on some precision measurements such as the magnetic and electric
dipole moments of fermions, as well as the Z boson rare decay Z ->
neutrino+antineutrino+ photon. If the underlying new physics is of a decoupling
nature, it is not expected that trilinear neutral gauge boson couplings may
affect considerably any of these observables. On the contrary, it is just in
the nonlinear scenario where these couplings have the more promising prospects
of being perceptible through high precision experiments.

</DOC>
<DOC>
<DOCNO> 99305 </DOCNO>
Vanshing Theorems for Quaternionic Kaehler Manifolds


  We discuss a peculiar interplay between the representation theory of the
holonomy group of a Riemannian manifold, the Weitzenboeck formula for the
Hodge-Laplace operator on forms and the Lichnerowicz formula for twisted Dirac
operators. For quaternionic Kaehler manifolds this leads to simple proofs of
eigenvalue estimates for Dirac and Laplace operators. Moreover it enables us to
determine which representations can contribute to harmonic forms. As a
corollary we prove the vanishing of certain odd Betti numbers on compact
quaternionic Kaehler manifolds of negative scalar curvature. We simplify the
proofs of several related results in the positive case.

</DOC>
<DOC>
<DOCNO> 119957 </DOCNO>
A Dust Cloud of Ganymede Maintained by Hypervelocity Impacts of


  A dust cloud of Ganymede has been detected by in-situ measurements with the
dust detector onboard the Galileo spacecraft. The dust grains have been sensed
at altitudes below five Ganymede radii (Ganymede radius = $\rm 2,635 km$). Our
analysis identifies the particles in the dust cloud surrounding Ganymede by
their impact direction, impact velocity, and mass distribution and implies that
they have been kicked up by hypervelocity impacts of micrometeoroids onto the
satellite's surface. We calculate the radial density profile of the particles
ejected from the satellite by interplanetary dust grains. We assume the yields,
mass and velocity distributions of the ejecta obtained from laboratory impact
experiments onto icy targets and consider the dynamics of the ejected grains in
ballistic and escaping trajectories near Ganymede. The spatial dust density
profile calculated with interplanetary particles as impactors is consistent
with the profile derived from the Galileo measurements. The contribution of
interstellar grains as projectiles is negligible. Dust measurements in the
vicinities of satellites by spacecraft detectors are suggested as a beneficial
tool to obtain more knowledge about the satellite surfaces, as well as dusty
planetary rings maintained by satellites through the impact ejecta mechanism.

</DOC>
<DOC>
<DOCNO> 11354 </DOCNO>
A novel method for the extraction of the condensate fraction of liquid


  We present a new, semi-phenomenologocal method to extract the condensate
fraction n_0(T) from two sets of measured responses of ^4He with identical
kinematis at T<T_c and T>T_c.

</DOC>
<DOC>
<DOCNO> 151629 </DOCNO>
Encoding a qubit in an oscillator


  Quantum error-correcting codes are constructed that embed a
finite-dimensional code space in the infinite-dimensional Hilbert space of a
system described by continuous quantum variables. These codes exploit the
noncommutative geometry of phase space to protect against errors that shift the
values of the canonical variables q and p. In the setting of quantum optics,
fault-tolerant universal quantum computation can be executed on the protected
code subspace using linear optical operations, squeezing, homodyne detection,
and photon counting; however, nonlinear mode coupling is required for the
preparation of the encoded states. Finite-dimensional versions of these codes
can be constructed that protect encoded quantum information against shifts in
the amplitude or phase of a d-state system. Continuous-variable codes can be
invoked to establish lower bounds on the quantum capacity of Gaussian quantum
channels.

</DOC>
<DOC>
<DOCNO> 71280 </DOCNO>
Resolved ${\mathbf {\gamma^*_L}}$ in hard collisions of virtual photons:


  The manifestations of QCD effects on quark and gluon distribution functions
of longitudinally polarized virtual photons involved in hard collisions are
investigated. It is shown that for moderate photon virtualities and in the
kinematical region accessible at HERA and LEP these effects are sizable and
significantly enhance theoretical predictions based on contributions of
transversally polarized virtual photon only.

</DOC>
<DOC>
<DOCNO> 84883 </DOCNO>
An Approximate Model of the Spacetime Foam


  An approximate model of the spacetime foam is offered in which a quantum
handle (wormhole) is a 5D wormhole-like solution. Neglecting the linear sizes
of the wormhole throat we can introduce a spinor field for an approximate and
effective description of the foam. The definition of the spinor field can be
made by a dynamic and non-dynamic ways. In the first case some field equations
are used and the second case leads to superspace. It is shown that : the
spacetime with the foam is similar to a dielectric with dipoles and
supergravity theories with a non-minimal interaction between spinor and
electromagnetic fields can be considered as an effective model for the
spacetime foam.

</DOC>
<DOC>
<DOCNO> 8670 </DOCNO>
Spinning up and down a Boltzmann gas


  Using the average method, we derive a close set of linear equations that
describes the spinning up of an harmonically trapped gas by a rotating
anisotropy. We find explicit expressions for the needed to transfer angular
momentum as well as the decay time induced by a static residual anisotropy.
These different time scales are compared with the measured nucleation time and
lifetime of vortices by the ENS group. We find a good agreement that may
emphasize the role played by the non-condensed component in thoses experiments.

</DOC>
<DOC>
<DOCNO> 101422 </DOCNO>
Wedderburn Polynomials over Division Rings


  A Wedderburn polynomial over a division ring K is a minimal polynomial of an
algebraic subset of K. Special cases of such polynomials include, for instance,
the minimal polynomials (over the center F=Z(K)) of elements of  K that are
algebraic over F. In this note, we give a survey on some of our ongoing work on
the structure theory of Wedderburn polynomials. Throughout the note, we work in
the general setting of an Ore skew polynomial ring  K[t,S,D].

</DOC>
<DOC>
<DOCNO> 10014 </DOCNO>
Hedging large risks reduces the transaction costs


  As soon as one accepts to abandon the zero-risk paradigm of Black-Scholes,
very interesting issues concerning risk control arise because different
definitions of the risk become unequivalent. Optimal hedges then depend on the
quantity one wishes to minimize. We show that a definition of the risk more
sensitive to the extreme events generically leads to a decrease both of the
probability of extreme losses and of the sensitivity of the hedge on the price
of the underlying (the `Gamma'). Therefore, the transaction costs and the
impact of hedging on the price dynamics of the underlying are reduced.

</DOC>
<DOC>
<DOCNO> 116950 </DOCNO>
Optimized Wakefield Computations Using A Network Model


  During the course of the last decade, traveling wave accelerating structures
for a future Linear Collider have been the object of intense R&D efforts. An
important problem is the efficient computation of the long range wakefield with
the ability to include small alignment and tuning errors. To that end, SLAC has
developed an RF circuit model with a demonstrated ability to reproduce
experimentally measured wakefields. The wakefield computation involves the
repeated solution of a deterministic system of equations over a range of
frequencies. By taking maximum advantage of the sparsity of the equations, we
have achieved significant performance improvements. These improvements make it
practical to consider simulations involving an entire linac ($\sim 10^3$
structures). One might also contemplate assessing, in real time, the impact of
fabrication errors on the wakefield as an integral part of quality control.

</DOC>
<DOC>
<DOCNO> 101097 </DOCNO>
The frozen-field approximation and the Ginzburg-Landau equations of


  The Ginzburg--Landau (GL) equations of superconductivity provide a
computational model for the study of magnetic flux vortices in type-II
superconductors. In this article we show through numerical examples and
rigorous mathematical analysis that the GL model reduces to the frozen-field
model when the charge of the Cooper pairs (the superconducting charge carriers)
goes to zero while the applied field stays near the upper critical field.

</DOC>
<DOC>
<DOCNO> 84967 </DOCNO>
Anisotropic Homogeneous Cosmologies in the Post-Newtonian Approximation


  In this paper we explore how far the post-Newtonian theory goes in overcoming
the difficulties associated with anisotropic homogeneous cosmologies in the
Newtonian approximation. It will be shown that, unlike in the Newtonian case,
the cosmological equations of the post-Newtonian approximation are much more in
the spirit of general relativity with regard to the nine Bianchi types and
issues of singularities. The situations of vanishing rotation and vanishing
shear are treated separately. The homogeneous Bianchi I model is considered as
an example of a rotation-free cosmology with anisotropy. It is found in the
Newtonian approximation that there are arbitrary functions that need to be
given for all time if the initial value problem is to be well-posed, while in
the post-Newtonian case there is no such need. For the general case of a
perfect fluid only the post-Newtonian theory can satisfactorily describe the
effects of pressure. This is in accordance with findings in an earlier paper
where the post-Newtonian approximation was applied to homogeneous cosmologies.
For a shear-free anisotropic homogeneous cosmology the Newtonian theory of
Heckmann and Sch\"ucking is explored. Comparisons with its relativistic and
post-Newtonian counterparts are made. In the Newtonian theory solutions exist
to which there are no analogues in general relativity. The post-Newtonian
approximation may provide a way out.

</DOC>
<DOC>
<DOCNO> 11701 </DOCNO>
Effects of Fe doping in La1/2Ca1/2MnO3


  The effect of Fe doping in the Mn site on the magnetic, transport and
structural properties of polycrystalline La1/2Ca1/2MnO3 was studied. Doping
with low Fe concentration (< 10%) strongly affects electrical transport and
magnetization. Long range charge order is disrupted even for the lowest doping
level studied (~2%). For Fe concentration up to 5% a ferromagnetic state
develops at low temperature with metallic like conduction and thermal
hysteresis. In this range, the Curie temperature decreases monotonously as a
function of Fe doping. Insulating behavior and a sudden depression of the
ferromagnetic state is observed by further Fe doping.

</DOC>
<DOC>
<DOCNO> 169837 </DOCNO>
On the origin of noisy states whose teleportation fidelity can be


  Recently Badziag \emph{et al.} \cite{badziag} obtained a class of noisy
states whose teleportation fidelity can be enhanced by subjecting one of the
qubits to dissipative interaction with the environment via amplitude damping
channel (ADC). We show that such noisy states result while sharing the states
(| \Phi ^{\pm}> =\frac{1}{\sqrt{2}}(| 00> \pm | 11>)) across ADC. We also show
that under similar dissipative interactions different Bell states give rise to
noisy entangled states that are qualitatively very different from each other in
the sense, only the noisy entangled states constructed from the Bell states (|
\Phi ^{\pm}>) can \emph{}be made better sometimes by subjecting the unaffected
qubit to a dissipative interaction with the environment. Importantly if the
noisy state is non teleporting then it can always be made teleporting with this
prescription. We derive the most general restrictions on improvement of such
noisy states assuming that the damping parameters being different for both the
qubits. However this curious prescription does not work for the noisy entangled
states generated from (| \Psi ^{\pm}> =\frac{1}{\sqrt{2}}(| 01> \pm | 10>)).
This shows that an apriori knowledge of the noisy channel might be helpful to
decide which Bell state needs to be shared between Alice and Bob. \emph{}

</DOC>
<DOC>
<DOCNO> 101995 </DOCNO>
A geometric proof of the existence of Whitney stratifications


  A stratification of a singular set, e.g. an algebraic or analytic variety,
is, roughly, a partition of it into manifolds so that these manifolds fit
together "regularly". A classical theorem of Whitney says that any complex
analytic set has a stratification. This result was extended by Lojasiewicz to
real (semi)analytic sets. In this paper we present a short geometric proof of
existence of stratifications based on Thom's transversality theorem and
Milnor's curve selection lemma and not relying on difficult results of
Lojasiewicz.

</DOC>
<DOC>
<DOCNO> 67848 </DOCNO>
A Model for the Colour Form Factor of the Proton


  The total cross-section and the jet cross-section differ at a proton-proton
collision. The latter is divergent if arbitrarily small transverse momenta are
allowed. Even with some fixed lower pt cutoff, increases the jet cross-section
much faster than the total cross-section at high energies. We have in this
paper studied how the divergence could be tamed by colour screening effects
among the partons. To do this we have built a proton model where we assign
momenta, positions and colour-charge to all partons in the proton. We find that
the relative behaviour of the cross-section can be better understood by the
inclusion of this effect.

</DOC>
<DOC>
<DOCNO> 119666 </DOCNO>
Objective Classification of Galaxy Spectra using the Information


  A new method for classification of galaxy spectra is presented, based on a
recently introduced information theoretical principle, the `Information
Bottleneck'. For any desired number of classes, galaxies are classified such
that the information content about the spectra is maximally preserved. The
result is classes of galaxies with similar spectra, where the similarity is
determined via a measure of information. We apply our method to approximately
6000 galaxy spectra from the ongoing 2dF redshift survey, and a mock-2dF
catalogue produced by a Cold Dark Matter-based semi-analytic model of galaxy
formation. We find a good match between the mean spectra of the classes found
in the data and in the models. For the mock catalogue, we find that the classes
produced by our algorithm form an intuitively sensible sequence in terms of
physical properties such as colour, star formation activity, morphology, and
internal velocity dispersion. We also show the correlation of the classes with
the projections resulting from a Principal Component Analysis.

</DOC>
<DOC>
<DOCNO> 120304 </DOCNO>
Are passive protostellar disks stable to self-shadowing?


  The uniqueness and stability of irradiated flaring passive protostellar disks
is investigated in the context of a simplified set of equations for the
vertical height H as a function of radius R. It is found that the well-known
flaring disk solution with H ~ R^{9/7} is not unique. Diverging solutions and
asymptotically conical (H ~ R) solutions are also found. Moreover, using
time-dependent linear perturbation analysis, it is found that the flaring disk
solution may become unstable to self-shadowing. A local enhancement in the
vertical height alters the functional form of irradiation grazing angle, and
causes the 'sunny side' of the enhancement to grow and the 'shadow side' to
collapse in a run-away fashion. This instability operates in regions of the
disk in which the cooling time is much shorter than the vertical sound crossing
time, which may occur in the outer regions of the passive irradiated disk if
dust and gas are sufficiently strongly thermally coupled. Processes that may
stabilize the disk, which include active accretion, irradiation from above
(e.g. a scattering corona) and low disk optical depth, are likely to operate
only at small or at large radius. The simple analysis of this Letter therefore
suggests that the instability may alter the flaring disk structure at
intermediate radii (between the actively accreting and fast rotating inner
regions and the optically thin outer regions).

</DOC>
<DOC>
<DOCNO> 8997 </DOCNO>
Multifractal behavior of linear polymers in disordered media


  The scaling behavior of linear polymers in disordered media modelled by
self-avoiding random walks (SAWs) on the backbone of two- and three-dimensional
percolation clusters at their critical concentrations p_c is studied. All
possible SAW configurations of N steps on a single backbone configuration are
enumerated exactly. We find that the moments of order q of the total number of
SAWs obtained by averaging over many backbone configurations display
multifractal behavior, i.e. different moments are dominated by different
subsets of the backbone. This leads to generalized coordination numbers \mu_q
and enhancement exponents \gamma_q, which depend on q. Our numerical results
suggest that the relation \mu_1 = p_ c \mu between the first moment \mu_1 and
its regular lattice counterpart \mu is valid.

</DOC>
<DOC>
<DOCNO> 102310 </DOCNO>
Intrinsic Volumes of the Brownian Motion Body


  Motivated from Gaussian processes, we derive the intrinsic volumes of the
infinite--dimensional Brownian motion body. The method is by discretization to
a class of orthoschemes. Numerical support is offered for a conjecture of
Sangwine-Yager, and another conjecture is offered on the rate of decay of
intrinsic volume sequences.

</DOC>
<DOC>
<DOCNO> 11499 </DOCNO>
Critical Currents and Vortex States at Fractional Matching Fields in


  We study vortex states and dynamics in 2D superconductors with periodic
pinning at fractional sub-matching fields using numerical simulations. For
square pinning arrays we show that ordered states form at 1/1, 1/2, and 1/4
filling fractions while only partially ordered states form at other filling
fractions, such as 1/3 and 1/5, in agreement with recent imaging experiments.
For triangular pinning arrays we observe matching effects at filling fractions
of 1/1, 6/7, 2/3, 1/3, 1/4, 1/6, and 1/7. For both square and triangular
pinning arrays we also find that, for certian sub-matching fillings, vortex
configurations depend on pinning strength. For weak pinning, ordering in which
a portion of the vortices are positioned between pinning sites can occur.
Depinning of the vortices at the matching fields, where the vortices are
ordered, is elastic while at the incommensurate fields the motion is plastic.
At the incommensurate fields, as the applied driving force is increased, there
can be a transition to elastic flow where the vortices move along the pinning
sites in 1D channels and a reordering transition to a triangular or distorted
triangular lattice. We also discuss the current-voltage curves and how they
relate to the vortex ordering at commensurate and incommensurate fields.

</DOC>
<DOC>
<DOCNO> 116501 </DOCNO>
Thermodynamic Equilibrium in Open Chemical Systems


  The article presents new model of equilibrium in open chemical systems
suggesting a linear dependence of the reaction shift from equilibrium in
presence of the external thermodynamic force. Basic equation of this model
contains traditional logarithmic term and a non-traditional parabolic term. At
isolated equilibrium the non-traditional term equals to zero turning the whole
equation to the traditional form of constant equation. This term coincides with
the excessive thermodynamic function revealing linear relationship between
logarithm of the thermodynamic activity coefficient and reaction extent at open
equilibrium. Discovered relationship prompts us to use in many systems a
combination of the linearity coefficient and reaction shift from true
equilibrium rather then activity coefficients. The coefficient of linearity can
be found by thermodynamic computer simulation while the shift is an independent
variable defining the open equilibrium state. Numerical data obtained by
various simulation techniques proved premise of the method of chemical
dynamics.

</DOC>
<DOC>
<DOCNO> 11688 </DOCNO>
Time-reversal symmetry in nonlinear optics


  The applicability of time-reversal symmetry to nonlinear optics is discussed,
both from macroscopic (Maxwell equations) and microscopic (quantum theoretical)
point of view. We find that only spatial operations can be applied for the
symmetry classification of nonlinear optical processes in magnetic, in
particular antiferromagnetic, materials. An example is given where both
operations (time reversal and a spatial operation) can yield different results.

</DOC>
<DOC>
<DOCNO> 8697 </DOCNO>
Aging and domain growth in Potassium-Lithium Tantalate crystals


  We present new experimental results on the dielectric constant in
orientational glasses K$_{1-x}$Li$_x$TaO$_3$ (KLT) with x < 0.05, together with
the detailed (analytic and numerical) study of a model which attributes the
observed aging to the motion of the wall of polarization domains. We show that
the dielectric constant after positive temperature jumps goes through a maximum
as a function of the subsequent time. This observation and those previously
reported (aging, cooling rate dependences, etc.) are compared with the
predictions of the model, in which the variations of the dielectric constant
are attributed to the change of polarization domain wall area. The total area
decreases by domain growth and increases by nucleation of new small domains
inside the larger ones. These two opposite variations are both hindered by
static random fields (equivalent to energy barriers) due to the frozen dipoles
borne by the off-center Li+ ions. Many results are well explained by a model
with a single energy barrier. However, some effects can only be understood if a
broad distribution of energy barriers is assumed. We use the experimental data
to determine this distribution and find it to be unimodal with a width
comparable to its most probable value.

</DOC>
<DOC>
<DOCNO> 120876 </DOCNO>
Modelling the Extinction Properties of Galaxies


  Recently (Granato, Lacey, Silva et al. 2000, astro-ph/0001308) we have
combined our spectrophotometric galaxy evolution code which includes dust
reprocessing (GRASIL, Silva et al. 1998) with semi-analytical galaxy formation
models (GALFORM, Cole et al. 1999). One of the most characteristic features of
the former is that the dust is divided in two main phases: molecular cloud
complexes, where stars are assumed to be born, and the diffuse interstellar
medium. As a consequence, stellar populations of different ages have different
geometrical relationships with the two phases, which is essential in
understanding several observed properties of galaxies, in particular those
undergoing major episodes of star formation at any redshift. Indeed, our merged
GRASIL+GALFORM model reproduces fairly well the SEDs of normal spirals and
starbursts from the far-UV to the sub-mm and their internal extinction
properties. In particular in the model the observed starburst attenuation law
(Calzetti 1999) is accounted for as an effect of geometry of stars and dust,
and has nothing to do with the optical properties of dust grains.

</DOC>
<DOC>
<DOCNO> 84189 </DOCNO>
Deformations of Accreting Neutron Star Crusts and Gravitational Wave


  Motivated by the narrow range of spin frequencies of nearly 20 accreting
neutron stars, Bildsten (1998) conjectured that their spin-up had been halted
by the emission of gravitational waves. He also pointed out that small
nonaxisymmetric temperature variations in the accreted crust will lead to
"wavy" electron capture layers, whose horizontal density variations naturally
create a mass quadrupole moment.
  We present a full calculation of the crust's elastic adjustment to these
density perturbations and find that the elastic response of the crust reduces
Bildsten's original estimate of the quadrupole moment in the thin outer crust
by a factor of 20-50. However, this basic picture, when applied to capture
layers in the deep inner crust, can generate quadrupoles in the necessary range
as long as there are ~5% lateral temperature variations in the inner crust. By
calculating the thermal flow throughout the core and the crust, we find that
temperature gradients this large are easily maintained by asymmetric heat
sources or lateral composition gradients in the crust.
  We also derive a general relation between the stresses and strains in the
crust and the maximum quadrupole moment they can generate. We show under quite
general conditions that maintaining a quadrupole of the magnitude necessary to
balance the accretion torque requires dimensionless strains close to 0.01 at
near-Eddington accretion rates, of order the breaking strain of conventional
materials.

</DOC>
<DOC>
<DOCNO> 150701 </DOCNO>
Quantisation of Extended Objects


  The `strong-coupling' perturbation theory over the inverse interaction
constant $1/g$ near the nontrivial solution of Lagrange equation is formulated.
The ordinary `week-coupling' perturbation theory over $g$ is described also to
compare both perturbation theories. The `strong-coupling' perturbation theory
is developed by unitary mapping of the quantum dynamics into the space with
local coordinates of (action, angle)-type.

</DOC>
<DOC>
<DOCNO> 118860 </DOCNO>
On the Emergence and Discovery of Hot Spots in Supernova Remnant 1987A


  We present the discovery of several new regions of interaction between the
ejecta and equatorial circumstellar ring of SN1987A, an interaction leading to
a much expanded development of the supernova remnant. We also trace the
development of the first such "hot spot," discovered in 1997, back to 1995.
Later hot spots seem to have emerged by early 1999. We discuss mechanisms for
the long delay between the first and later spots.

</DOC>
<DOC>
<DOCNO> 117583 </DOCNO>
Helium Emission in the Type Ic SN 1999cq


  We present the first unambiguous detection of helium emission lines in
spectra of Type Ic supernovae (SNe Ic). The presence of He I lines, with full
width at half maximum ~ 2000 km/s, and the distinct absence of any other
intermediate-width emission (e.g., Halpha), implies that the ejecta of SN Ic
1999cq are interacting with dense circumstellar material composed of almost
pure helium. This strengthens the argument that the progenitors of SNe Ic are
core-collapse events in stars that have lost both their hydrogen and helium
envelopes, either through a dense wind or mass-transfer to a companion. In this
way, SN 1999cq is similar to supernovae such as SN 1987K and SN 1993J that
helped firmly establish a physical connection between Type Ib and Type II
supernovae. The light curve of SN 1999cq is very fast, with an extremely rapid
rise followed by a quick decline. SN 1999cq is also found to exhibit a high
level of emission at blue wavelengths (< 5500 A), likely resulting from either
an unusually large amount of iron and iron-group element emission or
uncharacteristically low reddening compared with other SNe Ic.

</DOC>
<DOC>
<DOCNO> 150687 </DOCNO>
Asymmetric Orbifolds, Noncommutative Geometry and Type I String Vacua


  We investigate the D-brane contents of asymmetric orbifolds. Using T-duality
we find that the consistent description of open strings in asymmetric orbifolds
requires to turn on background gauge fields on the D-branes. We derive the
corresponding noncommutative geometry arising on such D-branes with mixed
Neumann-Dirichlet boundary conditions directly by applying an asymmetric
rotation to open strings with pure Dirichlet or Neumann boundary conditions. As
a concrete application of our results we construct asymmetric type I vacua
requiring open strings with mixed boundary conditions for tadpole cancellation.

</DOC>
<DOC>
<DOCNO> 170546 </DOCNO>
Quantum State Discrimination


  There are fundamental limits to the accuracy with which one can determine the
state of a quantum system. I give an overview of the main approaches to quantum
state discrimination. Several strategies exist. In quantum hypothesis testing,
a quantum system is prepared in a member of a known, finite set of states, and
the aim is to guess which one with the minimum probability of error. Error free
discrimination is also sometimes possible, if we allow for the possibility of
obtaining inconclusive results. If no prior information about the state is
provided, then it is impractical to try to determine it exactly, and it must be
estimated instead. In addition to reviewing these various strategies, I
describe connections between state discrimination, the manipulation of quantum
entanglement, and quantum cloning. Recent experimental work is also discussed.

</DOC>
<DOC>
<DOCNO> 83308 </DOCNO>
Towards a query language for annotation graphs


  The multidimensional, heterogeneous, and temporal nature of speech databases
raises interesting challenges for representation and query. Recently,
annotation graphs have been proposed as a general-purpose representational
framework for speech databases. Typical queries on annotation graphs require
path expressions similar to those used in semistructured query languages.
However, the underlying model is rather different from the customary graph
models for semistructured data: the graph is acyclic and unrooted, and both
temporal and inclusion relationships are important. We develop a query language
and describe optimization techniques for an underlying relational
representation.

</DOC>
<DOC>
<DOCNO> 119283 </DOCNO>
Epochs of Maximum Light and Bolometric Light Curves of Type Ia


  We present empirical fits to the UBVRI light curves of type Ia supernovae.
These fits are used to objectively evaluate light curve parameters. We find
that the relative times of maximum light in the filter passbands are very
similar for most objects. Surprisingly the maximum at longer wavelengths is
reached earlier than in the B and V light curves. This clearly demonstrates the
complicated nature of the supernova emission. Bolometric light curves for a
small sample of well-observed SNe Ia are constructed by integration over the
optical filters. In most objects a plateau or inflection is observed in the
light curve about 20-40 days after bolometric maximum. The strength of this
plateau varies considerably among the individual objects in the sample.
Furthermore the rise times show a range of several days for the few objects
which have observations early enough for such an analysis. On the other hand,
the decline rate between 50 and 80 days past maximum is remarkably similar for
all objects, with the notable exception of SN 1991bg. The similar late decline
rates for the supernovae indicate that the energy release at late times is very
uniform; the differences at early times is likely due to the radiation
diffusing out of the ejecta. With the exception of SN 1991bg, the range of
absolute bolometric luminosities of SNe Ia is found to be at least a factor of
2.5. The nickel masses derived from this estimate range from 0.4 to 1.1 Msun.
It seems impossible to explain such a mass range by a single explosion
mechanism, especially since the rate of gamma-ray escape at late phases seems
to be very uniform.

</DOC>
<DOC>
<DOCNO> 68036 </DOCNO>
Determination of the quantum part of the truly nonperturbative


  Using the effective potential approach for composite operators, we have
formulated a general method of calculation of the truly nonperturbative
Yang-Mills vacuum energy density in the covariant gauge QCD ground state
quantum models. It is defined as an integration of the truly nonperturbative
part of the full gluon propagator over the deep infrared region (soft momentum
region). A nontrivial minimization procedure makes it possible to determine the
value of the soft cutoff in terms of the corresponding nonperturbative scale
parameter, which is inevitably present in any nonperturbative model for the
full gluon propagator. We have shown for specific models of the full gluon
propagator explicitly that the use of the infrared enhanced and finite gluon
propagators lead to the vacuum energy density which is finite, always negative
and it has no imaginary part (stable vacuum), while the infrared vanishing
propagators lead to unstable vacuum and therefore they are physically
unacceptable.

</DOC>
<DOC>
<DOCNO> 84187 </DOCNO>
Finesse and mirror speed measurement for a suspended Fabry-Perot cavity


  We here present an investigation of the ringing effect observed on the VIRGO
mode-cleaner prototype MC30. The results of a numerical calculation show how a
simple empirical formula can determine the cavity expansion rate from the
oscillatory behavior. We also show how the simulation output can be adjusted to
estimate the finesse value of the suspended cavity.

</DOC>
<DOC>
<DOCNO> 12854 </DOCNO>
Oblique triangular antiferromagnetic phase in CsCu$_{1-x}$Co$_x$Cl$_3$


  The spin-1/2 stacked triangular antiferromagnet CsCu$_{1-x}$Co$_x$Cl$_3$ with
$0.015<x<0.032$ undergoes two phase transitions at zero field. The
low-temperature phase is produced by the small amount of Co$^{2+}$ doping. In
order to investigate the magnetic structures of the two ordered phases, the
neutron elastic scattering experiments have been carried out for the sample
with $x\approx 0.03$. It is found that the intermediate phase is identical to
the ordered phase of CsCuCl$_3$, and that the low-temperature phase is an
oblique triangular antiferromagnetic phase in which the spins form a triangular
structure in a plane tilted from the basal plane. The tilting angle which is
42$^{\circ}$ at $T=1.6$ K decreases with increasing temperature, and becomes
zero at $T_{\rm N2} =7.2$ K. An off-diagonal exchange term is proposed as the
origin of the oblique phase.

</DOC>
<DOC>
<DOCNO> 117347 </DOCNO>
A multipole-Taylor expansion for the potential of gravitational lens MG


  We employ a multipole-Taylor expansion to investigate how tightly the
gravitational potential of the quadruple-image lens MG J0414+0534 is
constrained by recent VLBI observations. These observations revealed that each
of the four images of the background radio source contains four distinct
components, thereby providing more numerous and more precise constraints on the
lens potential than were previously available. We expand the two-dimensional
lens potential using multipoles for the angular coordinate and a modified
Taylor series for the radial coordinate. After discussing the physical
significance of each term, we compute models of MG J0414+0534 using only VLBI
positions as constraints. The best-fit model has both interior and exterior
quadrupole moments as well as exterior m=3 and m=4 multipole moments. The
deflector centroid in the models matches the optical galaxy position, and the
quadrupoles are aligned with the optical isophotes. The radial distribution of
mass could not be well constrained. We discuss the implications of these models
for the deflector mass distribution and for the predicted time delays between
lensed components.

</DOC>
<DOC>
<DOCNO> 116253 </DOCNO>
Path Integral Monte Carlo Calculation of the Deuterium Hugoniot


  Restricted path integral Monte Carlo simulations have been used to calculate
the equilibrium properties of deuterium for two densities: 0.674 and 0.838
gcm^-3 (rs = 2.00 and 1.86) in the temperature range of 10000 < T < 1000000 K.
Using the calculated internal energies and pressures we estimate the shock
hugoniot and compare with recent Laser shock wave experiments. We study finite
size effects and the dependence on the time step of the path integral. Further,
we compare the results obtained with a free particle nodal restriction with
those from a self-consistent variational principle, which includes interactions
and bound states.

</DOC>
<DOC>
<DOCNO> 10871 </DOCNO>
Spectral density for a hole in an antiferromagnetic stripe phase


  Using variational trial wave function based on the string picture we study
the motion of a single mobile hole in the stripe phase of the doped
antiferromagnet. The holes within the stripes are taken to be static, the
undoped antiferromagnetic domains in between the hole stripes are assumed to
have alternating staggered magnetization, as is suggested by neutron scattering
experiments. The system is described by the t-t'-t''-J model with realistic
parameters and we compute the single particle spectral density.

</DOC>
<DOC>
<DOCNO> 72317 </DOCNO>
Analogue Models for T and CPT Violation in Neutral-Meson Oscillations


  Analogue models for CP violation in neutral-meson systems are studied in a
general framework. No-go results are obtained for models in classical mechanics
that are nondissipative or that involve one-dimensional oscillators. A complete
emulation is shown to be possible for a two-dimensional oscillator with
rheonomic constraints, and an explicit example with spontaneous T and CPT
violation is presented. The results have implications for analogue models with
electrical circuits.

</DOC>
<DOC>
<DOCNO> 70747 </DOCNO>
Connecting generalized parton distributions and light-cone wave


  The relation of generalized (skewed) quark distributions to nucleon wave
functions is discussed in the context of light-cone quantization.

</DOC>
<DOC>
<DOCNO> 170805 </DOCNO>
Storage of light in atomic vapor


  We report an experiment in which a light pulse is decelerated and trapped in
a vapor of Rb atoms, stored for a controlled period of time, and then released
on demand. We accomplish this storage of light by dynamically reducing the
group velocity of the light pulse to zero, so that the coherent excitation of
the light is reversibly mapped into a collective Zeeman (spin) coherence of the
Rb vapor.

</DOC>
<DOC>
<DOCNO> 122389 </DOCNO>
Comparative CMBology: Putting Things Together


  I present a series of diagrams which illustrate why the cosmic microwave
background (CMB) data favor certain values for the cosmological parameters.
Various methods to extract these parameters from CMB and non-CMB observations
are forming an ever-tightening network of interlocking constraints. I review
the increasingly precise constraints in the Omega_m - Omega_Lambda plane and
show why more cosmologists now prefer Lambda-CDM cosmologies to any other
leading model.

</DOC>
<DOC>
<DOCNO> 152039 </DOCNO>
Integrable hierarchies in Donaldson-Witten and Seiberg-Witten theories


  We review various aspects of integrable hierarchies appearing in N=2
supersymmetric gauge theories. In particular, we show that the blowup function
in Donaldson-Witten theory, up to a redefinition of the fast times, is a tau
function for a g-gap solution of the KdV hierarchy. In the case of
four-manifolds of simple type, instead, the blowup function becomes a tau
function corresponding to a multisoliton solution. We obtain a new expression
for the contact terms that links these results to the Whitham hierarchy
formulation of Seiberg-Witten theories.

</DOC>
<DOC>
<DOCNO> 151218 </DOCNO>
More on correlators and contact terms in {\cal N}=4 SYM at order g^4


  We compute two-point functions of chiral operators Tr(\Phi^k) for any k, in
{\cal N}=4 supersymmetric SU(N) Yang-Mills theory. We find that up to the order
g^4 the perturbative corrections to the correlators vanish for all N. The
cancellation occurs in a highly non trivial way, due to a complicated interplay
between planar and non planar diagrams. In complete generality we show that
this same result is valid for any simple gauge group. Contact term
contributions signal the presence of ultraviolet divergences. They are
arbitrary at the tree level, but the absence of perturbative renormalization in
the non singular part of the correlators allows to compute them unambiguously
at higher orders. In the spirit of the AdS/CFT correspondence we comment on
their relation to infrared singularities in the supergravity sector.

</DOC>
<DOC>
<DOCNO> 11871 </DOCNO>
Reply to the comment of Tallon et al. Cond-Mat/0008295 about Phys. Rev.


  It is shown both from a qualitative and quantitative analysis that the
T-dependence of the pure susceptibility detected by Tallon et al. in overdoped
compounds cannot explain the T-dependence of the Li NMR shift. This confirms
that the electronic correlations are still present in the overdoped regime as
pointed out in Phys. Rev. Lett. 83, 4381 (1999).

</DOC>
<DOC>
<DOCNO> 10426 </DOCNO>
A Novel Method for Sampling Alpha-Helical Protein Backbones


  We present a novel technique of sampling the configurations of helical
proteins. Assuming knowledge of native secondary structure, we employ assembly
rules gathered from a database of existing structures to enumerate the
geometrically possible three-dimensional arrangements of the constituent
helices. We produce a library of possible folds for twenty-five helical protein
cores. In each case, our method finds significant numbers of conformations
close to the native structure. In addition we assign coordinates to all atoms
for four of the twenty-five proteins and show that this has a small effect on
the number of near-native conformations. In the context of database driven
exhaustive enumeration our method performs extremely well, yielding significant
percentages of structures (between 0.02% and 82%) within 6 Angstroms of the
native structure. The method's speed and efficiency make it a valuable tool for
predicting protein structure.

</DOC>
<DOC>
<DOCNO> 151165 </DOCNO>
On the Moduli Space of the Localized 1-5 System


  We calculate the effective action for small velocity scattering of localized
1-branes and 5-branes. Momentum is allowed to flow in the direction along the
1-branes so that the moduli space has only 1/8 of the full supersymmetry.
Relative to the more familiar case with the 1-branes delocalized along the
5-branes, this introduces new moduli associated with the motion of the 1-branes
along the 5-branes. We consider in detail the moduli space metric for the
associated two body problem. Even for motion transverse to the 5-brane, our
results differ substantially from the delocalized case. However, this
difference only appears when both the 1-brane charge and the momentum charge
are localized. Despite the fact that, in a certain sense, 1-branes
spontaneously delocalize near a 5-brane horizon, the moduli space metric in
this limit continues to differ from the delocalized result. This fact may be of
use in developing a new description of the associated BPS bound states. The new
terms depend on the torus size $L$ in such a way that they give a finite
contribution in the $L \to \infty$ limit.

</DOC>
<DOC>
<DOCNO> 121988 </DOCNO>
The Birth, Evolution and Death of Star Clusters


  A dense-enough gas-accumulation evolves, over a few Myr of intensifying star
formation, to an embedded cluster. If it contains a sufficient amount of mass,
O stars form and explosively expel the remaining gas, whereas poorer clusters
reduce their embryonic gas content more gradually. The sudden expulsion of gas
unbinds most of a rich cluster, but a significant fraction of it can condense
by two-body interactions to become an open cluster despite a star-formation
efficiency as low as 30 per cent. Poorer clusters survive their gradual mass
loss more easily, but have short, relaxation-limited life-times. Pleiades-like
clusters may thus form as nuclei of expanding OB associations, by filling their
tidal radii and having large (1-2 pc) core-radii. A 'main-sequence' of clusters
is thus established. Ultimately, a cluster dies an explosive death through the
ever shortening relaxation time, and leaves a remnant that consists of about
4-10 stars arranged in a highly hierarchical and thus long-lived system.
Dynamical mass segregation in very young clusters is extremely rapid, and heats
a cluster substantially, which is partially off-set by the cooling from the
disruption of primordial binaries.

</DOC>
<DOC>
<DOCNO> 119690 </DOCNO>
Self-similar collapse of collisional gas in an expanding Universe


  Similarity solutions are found for the adiabatic collapse of density
perturbations $\delta M/M \propto r^{-s}$ $(s>0)$ in a flat universe containing
collisional gas only. The solutions are obtained for planar, cylindrical, and
spherical perturbations with zero initial pressure. For adiabatic index
$\gamma\ge 4/3$, a shock develops at a fixed fraction of the current turnaround
distance. Near the center of a spherical perturbations with $\gamma>4/3$ and
$s>1/2$, the gas is in quasi-hydrostatic equilibrium (pressure supported) and
has an asymptotic power law density profile, $\rho\sim r^{-3s/(s+1)}$,
independent of $\gamma$. For $s\le 1/2$, the profile depends on $\gamma$, the
pressure is finite, the temperature decreases inward, and gravity dominates
pressure causing a continuous inward flow. Although for $1/2<s<2$ the
temperature decreases at the center, the gas is pressure supported. The
pressure is finite in cylindrical perturbations for $s\le
2(\gamma-1)/(3\gamma-4)$, and in planar perturbations for any $s>0$. We also
derive the asymptotic behaviour of the gas variables near the center in a
universe dominated by collisionless matter. In such a universe, the gas in a
spherical perturbation with $s<2$ cannot be pressure supported and the
temperature approaches a constant near the center. The solutions and the
asymptotic behaviour are relevant for modelling the gas distribution in galaxy
clusters and pancake-like superclusters, and determining the structure of
haloes of self-interacting dark matter with large interaction cross section.

</DOC>
<DOC>
<DOCNO> 150937 </DOCNO>
A configuration of 11-dimensional curved superspace as backgrounds for


  We calculate all of vielbein superfields up to second order in anticommuting
coordinates in terms of the component fields of 11-dimensional on-shell
supergravity by using `Gauge completion'. This configuration of superspace
holds the $\kappa $-symmetry for supermembrane Lagrangian and represents
11-dimensional on-shell supergravity.

</DOC>
<DOC>
<DOCNO> 121596 </DOCNO>
The kinematics of 3:1-merger remnants and the formation of


  We test the formation of low-luminosity elliptical galaxies through
collisionless mergers of unequal-mass disk galaxies. The kinematic properties
of a small survey of simulated merger end-products with initial disk mass
ratios of 3:1 is compared to a sample of seven low-luminosity galaxies observed
by Rix et al. that were chosen photometrically to be "ellipticals". In this
paper, we go beyond a comparison in terms of global properties (using one
number to characterize a model or a galaxy e.g. <a4>, ellipticity at some fixed
radius or central velocity dispersion) and examine the detailed kinematics as
function of galactocentric distance. The merger remnants are ``observed''
through a slit along the major and minor axis, using a pixel binning and slit
width similar to the one used during the spectroscopic observations. We compare
the rotational support (v/sigma) of the merger remnants, the normalized
rotation on the minor axis and the major axis Gauss-Hermite moments h3, to that
of the observed galaxies. The N-body remnants are very flattened when viewed
edge-on (<epsilon> = 0.6) and should be inclined before making a fair
comparison with the Rix et al. data set (which has <epsilon> = 0.3). When the
merger remnants are appropriately inclined, their v/sigma profiles rise slower
than the observed ones. Note that even when the remnants are viewed edge-on,
the v/sigma profiles do not match the observations. The detailed comparison of
the observations with purely collisionless 3:1-merger remnants suggests that
this kind of dissipationless merger is not likely to be the dominant formation
channel for low-luminosity elliptical galaxies. (abridged)

</DOC>
<DOC>
<DOCNO> 118586 </DOCNO>
Radio and X-ray Signatures of Merging Neutron Stars


  We describe the possible electromagnetic signals expected from the
magnetospheric interactions of a neutron star binary prior to merger. We find
that both radio and X-ray signals of detectable strength are possible. We
discuss possible links with the phenomenon of gamma-ray bursts and describe the
prospects for direct detection of these signals in searches for radio and X-ray
transients.

</DOC>
<DOC>
<DOCNO> 150887 </DOCNO>
Standard Cosmology from Sigma-Model


  We investigate (4+1)- and (5+0)-dimensional gravity coupled to a non-compact
scalar field sigma-model and a perfect fluid within the context of the
Randall-Sundrum scenario. We find cosmological solutions with a rolling fifth
radius and a family of warp factors. Included in this family are both the
original Randall-Sundrum solution and the self-tuning solution of Kachru,
Schulz and Silverstein. Our solutions exhibit conventional cosmology.

</DOC>
<DOC>
<DOCNO> 122079 </DOCNO>
X-ray measurements of the field and particle energy distributions in the


  A follow-up X-ray study was made of the west lobe of the radio galaxy Fornax
A, (NGC 1316) based on new ASCA observations made in 1997 for 98 ks, and
incorporating the previous observation in 1994 for 39 ks. The 0.7--10 keV
spectrum of the emission can be described by a power-law of energy index 0.74
+/- 0.10, which agrees with the synchrotron radio index of 0.9 +/- 0.2.
Therefore, the X-rays are reconfirmed to arise via inverse-Compton scattering
of the cosmic microwave photons, as Kaneda et al. (1995) and Feigelson et al.
(1995) concluded. The surface brightness of the inverse-Compton X-rays exhibits
a relatively flat distribution over the west lobe, indicative of an
approximately spherical emissivity distribution with a radius of ~11' (75 kpc).
n contrast, the 1.4 GHz radio image by Ekers et al. (1983) exhibits a rim-
brightened surface brightness, consistentwith a shell-like emissivity
distribution whose inner and outer boundaries are 4' and 11', respectively.
These morphological differences between radio and X-rays suggest that the
relativistic electrons are distributed homogeneously over the lobe volume,
whereas the magnetic field is amplified toward the lobe rim region.

</DOC>
<DOC>
<DOCNO> 12993 </DOCNO>
New Method for Phase transitions in diblock copolymers: The Lamellar


  A new mean-field type theory is proposed to study order-disorder transitions
(ODT) in block copolymers. The theory applies to both the weak segregation (WS)
and the strong segregation (SS) regimes. A new energy functional is proposed
without appealing to the random phase approximation (RPA). We find new terms
unaccounted for within RPA. We work out in detail transitions to the lamellar
state and compare the method to other existing theories of ODT and numerical
simulations. We find good agreements with recent experimental results and
predict that the intermediate segregation regime may have more than one scaling
behavior.

</DOC>
<DOC>
<DOCNO> 118343 </DOCNO>
Contributions to the Power Spectrum of Cosmic Microwave Background from


  We estimate the contributions to the cosmic microwave background radiation
(CMBR) power spectrum from the static and kinematic Sunyaev-Zel'dovich (SZ)
effects, and from the moving cluster of galaxies (MCG) effect. We conclude, in
agreement with other studies, that at sufficiently small scales secondary
fluctuations caused by clusters provide important contributions to the CMBR. At
$\ell \gtrsim 3000$, these secondary fluctuations become important relative to
lensed primordial fluctuations. Gravitational lensing at small angular scales
has been proposed as a way to break the ``geometric degeneracy'' in determining
fundamental cosmological parameters. We show that this method requires the
separation of the static SZ effect, but the kinematic SZ effect and the MCG
effect are less important. The power spectrum of secondary fluctuations caused
by clusters of galaxies, if separated from the spectrum of lensed primordial
fluctuations, might provide an independent constraint on several important
cosmological parameters.

</DOC>
<DOC>
<DOCNO> 69828 </DOCNO>
The spin correlation in top quark production: QCD corrections vs


  We discuss top quark production and its subsequent decay at lepton colliders
including both QCD corrections and anomalous gamma / Z - t t-bar couplings. The
off-diagonal spin basis for the top and anti-top quarks is shown to be useful
to probe the anomalous couplings.

</DOC>
<DOC>
<DOCNO> 122138 </DOCNO>
Gamma Ray Bursts, Cosmic Ray Origin, and the Unidentified EGRET Sources


  Statistical arguments show that the volume- and time-averaged kinetic power
of GRBs and fireball transients (FTs) into an L* galaxy like the Milky Way is
at the level of 10^40 ergs/s. This number, though with wide uncertainties
related to the internal or external shock efficiency, is sufficient to power
hadronic cosmic rays observed locally. The release of energy by the high-mass
progenitor stars of GRBs and FTs is sufficient to power the ultrahigh energy
cosmic rays, as already shown by Waxman and Vietri in 1995. It is sufficient to
power the cosmic rays above the knee of the cosmic-ray spectrum. Indeed, all
hadronic cosmic rays could originate from the high-mass (>~ 100 M_o) stars that
collapse to black holes, in the process forming GRBs and FTs. This source class
represents a new solution to the problem of cosmic-ray origin. The ~10^4 - 10^7
black holes made by these stars could make their presence known by radiating as
they accrete from the ISM, by microlensing background radiations, and by
forming luminous binary systems. Some unidentified EGRET sources could be
isolated black holes that accrete from the ISM. Better imaging and sensitivity
with GLAST and TeV observatories will test this model for the unidentified
gamma-ray sources, and this theory for cosmic-ray origin.

</DOC>
<DOC>
<DOCNO> 102024 </DOCNO>
One-sided invertibility of binomial functional operators with a shift in


  Let $\Gamma$ be an oriented Jordan smooth curve and $\alpha$ be a
diffeomorphism of $\Gamma$ onto itself which has an arbitrary nonempty set of
periodic points. We prove criteria for one-sided invertiblity of the binomial
functional operator \[ A=aI-bW \] where $a$ and $b$ are continuous functions,
$I$ is the identity operator, $W$ is the shift operator $Wf=f\circ\alpha$, in a
reflexive rearrangement-invariant space $X(\Gamma)$ with Boyd indices
$\alpha_X,\beta_X$ and Zippin indices $p_X,q_X$ satisfying inequalities \[
0<\alpha_X=p_X\le q_X=q_X<1. \]

</DOC>
<DOC>
<DOCNO> 69427 </DOCNO>
Constraining Anomaly Mediated Supersymmetry Breaking Framework via


  The ongoing high precision E821 Brookhaven National Laboratory experiment on
muon g-2 is promising to probe a theory involving supersymmetry. We have
studied the constraints on the minimal Anomaly Mediated Supersymmetry Breaking
(AMSB) model using the current data of muon g-2 from Brookhaven. A scenario of
seeing no deviation from the Standard Model is also considered, within a
$2\sigma$ limit of the combined error from the Standard Model result and the
Brookhaven predicted uncertainty level. The resulting constraint is found to be
complementary to what one obtains from $b \to s+ \gamma$ bounds within the AMSB
scenario, since only a definite sign of $\mu$ is effectively probed via $b \to
s+ \gamma$. A few relevant generic features of the model are also described for
disallowed regions of parameter space.

</DOC>
<DOC>
<DOCNO> 152366 </DOCNO>
On the stability of the Quantum Hall soliton


  In this note we investigate the stability of the classical ground state of
the Quantum Hall Soliton proposed recently in hep-th/0010105 . We explore two
possible perturbations which are not spherically symmetric and we find that the
potential energy decreases in both case. This implies that the system either
decays or is dynamically stabilized (because of the presence of magnetic
fields). If one makes an extra assumption that in the real quantum treatment of
the problem string ends and D0 branes move together (as electrons and vortices
in the Quantum Hall effect), a static equilibrium configuration is possible.

</DOC>
<DOC>
<DOCNO> 151424 </DOCNO>
Comments on Noncommutative Open String Theory: V-duality and Holography


  In this paper we study the interplay of electric and magnetic backgrounds in
determining the decoupling limit of coincident D-branes towards a
noncommutative Yang-Mills (NCYM) or open string (NCOS) theory. No decoupling
limit has been found for NCYM with space-time noncommutativity. It is suggested
that there is a new duality, which we call V-duality, which acts on NCOS with
both space-space and space-time noncommutativity, resulting from decoupling in
Lorentz-boost related backgrounds. We also show that the holographic
correspondence, previously suggested by Li and Wu, between NCYM and its
supergravity dual can be generalized to NCOS as well.

</DOC>
<DOC>
<DOCNO> 10296 </DOCNO>
Difference between microscopic and effective overlaps in the


  We investigate parametrizations required to reproduce observed Fermi surfaces
of overdoped and slightly underdoped LSCO in two different models. One is the
standard three-band saddle-point slave boson (SB). The other is a model of CuO4
`molecules' randomly tiled in the plane, emphasizing the distinction between
the local overlap, always the full (bare) one, and the effective overlap,
connected with the reduced bandwidth due to the random tiling (RT). We conclude
this distinction is physically significant for underdoped, but not for
overdoped LSCO. This is consistent with the observed open Fermi surfaces being
due to correlation effects.

</DOC>
<DOC>
<DOCNO> 118813 </DOCNO>
A Central Engine for Cosmic Gamma-Ray Burst Sources


  One of a family previously proposed ``central engines'' for cosmic gamma-ray
burst sources (Klu\'zniak & Ruderman 1998) is considered in some detail. A
steadily accreting $10^6$ Gauss magnetic white dwarf should ultimately collapse
to a strongly differentially rotating, millisecond-rotation-period neutron star
for a wide range of steady accretion rates and initial masses if the accreting
white dwarf has an evolved O-Ne-Mg composition. A similar neutron star could
also result from an initial C-O white dwarf but only for more constrained
accretion rates. Because the collapsing white dwarf begins as a $\gamma=4/3$
polytrope, the final neutron star's spin-rate increases strongly with
cylindrical radius. A stable wind-up of the neutron star's poloidal magnetic
field then produces buoyant magnetic toroids which grow, break loose, rise, and
partly penetrate the neutron star surface to form a transient, $B\approx
10^{17}$ G millisecond spin-period pulsar with a powerful pulsar wind (Usov
1992). This pulsar wind emission is then rapidly suppressed by the surface
shear motion from the strong stellar differential rotation. This wind-up and
transient pulsar formation can occur at other times on different cylinders
and/or repeat on the same one, with (re-)wind up and surface penetration time
scales hugely longer han the neutron star's millisecond spin period. In this
way, differential rotation both opens and closes the doors which allow neutron
star spin-energy to be emitted in powerful bursts of pulsar wind. Predictions
of this model compare favorably to needed central engine properties of
gamma-ray burst sources (total energy, duration, sub-burst fluctuations and
time scales, variability among burst events, and baryon loading).

</DOC>
<DOC>
<DOCNO> 100390 </DOCNO>
Enhanced inverse-cascade of energy in the averaged Euler equations


  For a particular choice of the smoothing kernel, it is shown that the system
of partial differential equations governing the vortex-blob method corresponds
to the averaged Euler equations. These latter equations have recently been
derived by averaging the Euler equations over Lagrangian fluctuations of length
scale $\a$, and the same system is also encountered in the description of
inviscid and incompressible flow of second-grade polymeric (non-Newtonian)
fluids. While previous studies of this system have noted the suppression of
nonlinear interaction between modes smaller than $\a$, we show that the
modification of the nonlinear advection term also acts to enhance the
inverse-cascade of energy in two-dimensional turbulence and thereby affects
scales of motion larger than $\a$ as well. This latter effect is reminiscent of
the drag-reduction that occurs in a turbulent flow when a dilute polymer is
added.

</DOC>
<DOC>
<DOCNO> 85419 </DOCNO>
The dipolar zero-modes of Einstein action: An informal summary with some


  We recall the main features of metric vacuum fluctuations which have the
global property int d^4x sqrt{g(x)} R(x) = 0, even though R(x) does not vanish
locally. We stress that these fluctuations could mediate an anomalous coupling
between the gravitational field and coherent matter. Some new issues are
discussed: (1) these fluctuations still imply that <T_{mu nu}(x)>=0; (2) they
are not extrema of the action; (3) for finite duration, their volume in phase
space is not zero; (4) vacuum fluctuations of this kind are not allowed in QED;
(5) their null-action property is a nonperturbative feature; (6) any -real-
pure e.m. field generates zero-modes of this kind, too, up to terms of order
G^2.

</DOC>
<DOC>
<DOCNO> 151759 </DOCNO>
Logarithmic Conformal Field Theory Through Nilpotent Conformal


  We study logarithmic conformal field theories (LCFTs) through the
introduction of nilpotent conformal weights. Using this device, we derive the
properties of LCFT's such as the transformation laws, singular vectors and the
structure of correlation functions. We discuss the emergence of an extra energy
momentum tensor, which is the logarithmic partner of the energy momentum
tensor.

</DOC>
<DOC>
<DOCNO> 8730 </DOCNO>
RVB description of the low-energy singlets of the spin 1/2 kagome


  {Extensive calculations in the short-range RVB (Resonating valence bond)
subspace on both the trimerized and the regular (non-trimerized) Heisenberg
model on the kagome lattice show that short-range dimer singlets capture the
specific low-energy features of both models. In the trimerized case the singlet
spectrum splits into bands in which the average number of dimers lying on one
type of bonds is fixed. These results are in good agreement with the mean field
solution of an effective model recently introduced. For the regular model one
gets a continuous, gapless spectrum, in qualitative agreement with exact
diagonalization results.

</DOC>
<DOC>
<DOCNO> 151703 </DOCNO>
Convergence Theorem for Non-commutative Feynman Graphs and


  We present a rigorous proof of the convergence theorem for the Feynman graphs
in arbitrary massive Euclidean quantum field theories on non-commutative R^d
(NQFT). We give a detailed classification of divergent graphs in some massive
NQFT and demonstrate the renormalizability of some of these theories.

</DOC>
<DOC>
<DOCNO> 70278 </DOCNO>
Massive field contributions to the QCD vacuum tunneling amplitude


  For the one-loop contribution to the QCD vacuum tunneling amplitude by quarks
of generic mass value, we make use of a calculational scheme exploiting a large
mass expansion together with a small mass expansion. The large mass expansion
for the effective action is given by a series involving higher-order
Seeley-DeWitt coefficients, and we carry this expansion up to order
$1/(m\rho)^8$, where $m$ denotes mass of the quark and $\rho$ the instanton
size parameter. For the small mass expansion, we use the known exact expression
for the particle propagation functions in an instanton background and evaluate
explicitly the effective action to order $(m\rho)^2$. A smooth interpolation of
the results from both expansions suggests that the quark contribution to the
instanton tunneling amplitude have a relatively simple $m\rho$-dependent
behavior.

</DOC>
<DOC>
<DOCNO> 170284 </DOCNO>
Template-stripped gold surfaces with 0.4 nm rms roughness suitable for


  Using a template-stripping method, macroscopic gold surfaces with
root-mean-square (rms) roughness less than 0.4 nm have been prepared, making
them useful for studies of surface interactions in the nanometer range. The
utility of such substrates is demonstrated by measurements of the Casimir force
at surface separations between 20 and 100 nm, resulting in good agreement with
theory. The significance and quantification of this agreement is addressed, as
well as some methodological aspects regarding the measurement of the Casimir
force with high accuracy.

</DOC>
<DOC>
<DOCNO> 12262 </DOCNO>
Optical studies of Cr$^{3+}$-Cr$^{2+}$ pair center in KZnF$_{3}$ crystal


  Optical absorption spectra of Cr$^{3+}$-Cr$^{2+}$ pair center in
KZnF$_{3}$:Cr$^{3+}$,Cr$^{2+}$ crystal were investigated in wide temperature
range. Broad band at 30800 cm$^{-1}$ is attributed to cation-cation
(e_g)-electron transfer transition. Narrow lines with maxima at 16720 cm$^{-1}$
and 19880 cm$^{-1}$ have been assigned to purely electronic exchange-induced
electric-dipole transitions from the ground
(Cr$^{3+}$,(^4A_{2g});Cr$^{2+}$,(^5E_g)) state to excited
(Cr$^{3+}$,(^4A_{2g});Cr$^{2+}$,(^3E_g^a)) and
(Cr$^{3+}$,(^4A_{2g});Cr$^{2+}$,(^3E_g^b)) states, respectively. It's vibronic
satellites corresponding to (a_{1g}) local mode of Cr$^{3+}$ fluorine
octahedron of the pair are also observed. Energy of the local mode for the
ground and mentioned excited states are 580, 540 and 530 cm$^{-1}$. Instead of
expected double exchange for mixed valence pair ferromagnetic superexchange for
Cr$^{3+}$-Cr$^{2+}$ pair in KZnF$_{3}$ crystal is realized. Exchange integral
(J=-14.9\pm0.4) cm$^{-1}$ and Jahn-Teller splitting (\Delta_{JT}=340\pm40)
cm$^{-1}$ for the ground state of the pair were obtained by analysis of the
temperature dependence of absorption lines. Important features of the crossover
double exchange - ferromagnetic superexchange are discussed.

</DOC>
<DOC>
<DOCNO> 71257 </DOCNO>
On the Evolution of the Neutrino State inside the Sun


  We reexamine the conventional physical description of the neutrino evolution
inside the Sun. We point out that the traditional resonance condition has
physical meaning only in the limit of small values of the neutrino mixing
angle, theta<<1. For large values of theta, the resonance condition specifies
neither the point of the maximal violation of adiabaticity in the nonadiabatic
case, nor the point where the flavor conversion occurs at the maximal rate in
the adiabatic case. The corresponding correct conditions, valid for all values
of theta including theta>pi/4, are presented. An adiabaticity condition valid
for all values of theta is also described. The results of accurate numerical
computations of the level jumping probability in the Sun are presented. These
calculations cover a wide range of Delta m^2, from the vacuum oscillation
region to the region where the standard exponential approximation is good. A
convenient empirical parametrization of these results in terms of elementary
functions is given. The matter effects in the so-called "quasi-vacuum
oscillation regime" are discussed. Finally, it is shown how the known
analytical results for the exponential, 1/x, and linear matter distributions
can be simply obtained from the formula for the hyperbolic tangent profile. An
explicit formula for the jumping probability for the distribution N_e ~
(coth(x/l) +- 1) is obtained.

</DOC>
<DOC>
<DOCNO> 121893 </DOCNO>
Evolution of the Internal Dynamics of Galaxy Clusters


  We consider a sample of 51 distant galaxy clusters at 0.15<z<0.9 (<z> about
0.3), each cluster having at least 10 galaxies with available redshift in the
literature. We select member galaxies, analyze the velocity dispersion
profiles, and evaluate in a homogeneous way cluster velocity dispersions and
virial masses. We apply the same procedures already recently applied on a
sample of nearby clusters (z<0.15, Girardi et al. 1998b) in order to properly
analyze the possible dynamical evolution of galaxy clusters. We remark problems
induced by the poor sampling and the small spatial extension of the sampled
cluster region in the computation of velocity dispersion. We do not find any
significant difference between nearby and distant clusters. In particular, we
consider the galaxy spatial distribution, the shape of the velocity dispersion
profile, and the relations between velocity dispersion and X-ray luminosity and
temperature. Our results imply little dynamical evolution in the range of
redshift spanned by our cluster sample, and suggest that the typical redshift
of cluster formation is higher than that of the sample we analyze.

</DOC>
<DOC>
<DOCNO> 100162 </DOCNO>
On Complexes Equivalent to $\mathbb{S}^3$-bundles over $\mathbb{S}^4$


  There has been renewed interest in $\mathbb{S}^3$-bundles over $\mathbb{S}^4$
since K. Grove and W. Ziller constructed metrics on nonnegative curvature on
the total spaces of these bundles. In this paper we write down necessary and
sufficient conditions for a CW complex to be homotopy equivalent to such a
bundle. We also show that for a manifold homotopy equivalent to such a bundle,
in certain cases, there is no obstruction to homeomorphism. We use this to show
that the Berger manifold, $\text{Sp}(2)/\text{Sp}(1)$, is PL-homeomorphic to
such a bundle. This question was raised in the paper by Grove and Ziller since
this manifold, which admits a normal homogeneous metric of positive sectional
curvature, has the cohomology ring of such a bundle.
  The principal technique used is the study of the Serre spectral sequence of
various fibrations.

</DOC>
<DOC>
<DOCNO> 117205 </DOCNO>
A sandpile model with tokamak-like enhanced confinement phenomenology


  Confinement phenomenology characteristic of magnetically confined plasmas
emerges naturally from a simple sandpile algorithm when the parameter
controlling redistribution scalelength is varied. Close analogues are found for
enhanced confinement, edge pedestals, and edge localised modes (ELMs), and for
the qualitative correlations between them. These results suggest that tokamak
observations of avalanching transport are deeply linked to the existence of
enhanced confinement and ELMs.

</DOC>
<DOC>
<DOCNO> 11944 </DOCNO>
Ab Initio Molecular Dynamics Simulation of Liquid Ga_xAs_{1-x} Alloys


  We report the results of ab initio molecular dynamics simulations of liquid
Ga_xAs_{1-x} alloys at five different concentrations, at a temperature of 1600
K, just above the melting point of GaAs. The liquid is predicted to be metallic
at all concentrations between x = 0.2 and x = 0.8, with a weak resistivity
maximum near x = 0.5, consistent with the Faber-Ziman expression. The
electronic density of states is finite at the Fermi energy for all
concentrations; there is, however, a significant pseudogap especially in the
As-rich samples. The Ga-rich density of states more closely resembles that of a
free-electron metal. The partial structure factors show only a weak indication
of chemical short-range order. There is also some residue of the covalent
bonding found in the solid, which shows up in the bond-angle distribution
functions of the liquid state. Finally, the atomic diffusion coefficients at
1600K are calculated to be 2.1 \times 10^{-4} cm^2/sec for Ga ions in
Ga_{0.8}As_{0.2} and 1.7 \times 10^{-4} cm^2/sec for As ions in
Ga_{0.2}As_{0.8}.

</DOC>
<DOC>
<DOCNO> 84334 </DOCNO>
Canonical Formulation of Gravitational Teleparallelism in 2+1 Dimensions


  We consider the most general class of teleparallel gravitational {}{}theories
quadratic in the torsion tensor, in three space-time dimensions, and carry out
a detailed investigation of its Hamiltonian formulation in Schwinger's time
gauge. This general class is given by a family of three-parameter theories. A
consistent implementation of the Legendre transform reduces the original theory
to a one-parameter family of theories. By calculating Poisson brackets we show
explicitly that the constraints of the theory constitute a first-class set.
Therefore the resulting theory is well defined with regard to time evolution.
The structure of the Hamiltonian theory rules out the existence of the
Newtonian limit.

</DOC>
<DOC>
<DOCNO> 11301 </DOCNO>
Quantum phase transitions in d-wave superconductors


  Motivated by the strong, low temperature damping of nodal quasiparticles
observed in some cuprate superconductors, we study quantum phase transitions in
d_{x^2-y^2} superconductors with a spin-singlet, zero momentum, fermion
bilinear order parameter. We present a complete, group-theoretic classification
of such transitions into 7 distinct cases (including cases with nematic order)
and analyze fluctuations by the renormalization group. We find that only 2, the
transitions to d_{x^2-y^2}+is and d_{x^2-y^2} + i d_{xy} pairing, possess
stable fixed points with universal damping of nodal quasiparticles; the latter
leaves the gapped quasiparticles along (1,0), (0,1) essentially undamped.

</DOC>
<DOC>
<DOCNO> 178411 </DOCNO>
Cranked Relativistic Hartree-Bogoliubov Theory: Formalism and


  Cranked Relativistic Hartree-Bogoliubov theory without and with approximate
particle number projection by means of the Lipkin-Nogami method is presented in
detail as an extension of Relativistic Mean Field theory with pairing
correlations to the rotating frame. Pairing correlations are taken into account
by a finite range two-body force of Gogny type. The applicability of this
theory to the description of rotating nuclei is studied in detail on the
example of superdeformed bands in even-even nuclei of the $A\sim 190$ mass
region. Different aspects such as the importance of pairing and particle number
projection, the dependence of the results on the parametrization of the RMF
Lagrangian and Gogny force etc. are investigated in detail. It is shown that
without any adjustment of new parameters the best description of experimental
data is obtained by using the well established parameter sets NL1 for the
Lagrangian and D1S for the pairing force. Contrary to previous studies at spin
zero it is found that the increase of the strength of the Gogny force is not
necessary in the framework of Relativistic Hartree-Bogoliubov theory provided
that particle number projection is performed.

</DOC>
<DOC>
<DOCNO> 80861 </DOCNO>
Zero Temperature String Breaking with Staggered Quarks


  The separation of a heavy quark and antiquark pair leads to the formation of
a tube of flux, or "string", which should break in the presence of light
quark-antiquark pairs. This expected zero-temperature phenomenon has proven
elusive in simulations of lattice QCD. In an extension of work reported last
year we present clear evidence for string breaking in QCD with two flavors of
dynamical staggered sea quarks and apply our results to a simple three-state
mixing model for string breaking. We find that mixing is weak and falls to zero
at level crossing.

</DOC>
<DOC>
<DOCNO> 151246 </DOCNO>
Gravitinos in non-Ricci-flat backgrounds


  We discuss the gauge invariance and "mass" of the Rarita-Schwinger field in a
background spacetime which is assumed to be Einstein but not necessarily
Ricci-flat.

</DOC>
<DOC>
<DOCNO> 84236 </DOCNO>
A slowly rotating perfect fluid body in an ambient vacuum


  A global model of a slowly rotating perfect fluid ball in general relativity
is presented. To second order in the rotation parameter, the junction surface
is an ellipsoidal cylinder. The interior is given by a limiting case of the
Wahlquist solution, and the vacuum region is not asymptotically flat. The
impossibility of joining an asymptotically flat vacuum region has been shown in
a preceding work.

</DOC>
<DOC>
<DOCNO> 70880 </DOCNO>
Two-photon reactions at high energies


  We present a short overview over the different contributions to high energy
photon photon scattering and explore the possibilities of tuning the sizes of
the scattered objects by changing the virtuality of the photons. We compare the
experimental data with model calculations. The difficulties with inclusive
charm production are discussed.

</DOC>
<DOC>
<DOCNO> 116728 </DOCNO>
Beam Current Monitors in the Nlcta


  The current profile along the 126 ns, multi-bunch beam pulse in the Next
Linear Collider Test Accelerator (NLCTA) is monitored with fast toroids (rise
time ~1 ns). Inserted at several positions along the beam line, they allow us
to track current transmission as a function of position along the bunch train.
Various measurements, such as rise time, current, width, and slope, are made on
the digitized signals, which can be corrected in software by means of stored
frequency response files. The design and implementation of these devices is
described.

</DOC>
<DOC>
<DOCNO> 70267 </DOCNO>
A Comparison of the Physics Potential of Future Long Baseline Neutrino


  We compare the generic physics potential of various combinations of
conventional Wide Band or Neutrino Factory Beams with different detectors to
determine several oscillation parameters in long baseline experiments. For each
combination of beam and detector we show the precision which can be obtained
for the leading oscillation parameters $\dm{31}$ and $\sin^2 2\theta_{23}$.
Furthermore we show the sensitivity to $\sin^2 2\theta_{13}$ and the range in
$\sin^2 2\theta_{13}$ for which the sign of $\dm{31}$ can be extracted via
matter effects. The results suggest that existing conventional Wide Band Beam
and detector technology can be used to considerably improve the precision of
neutrino properties until a neutrino factory will be built.

</DOC>
<DOC>
<DOCNO> 178646 </DOCNO>
The one-pion-exchange three-nucleon force and the $A_y$ puzzle


  We consider a new three-nucleon force generated by the exchange of one pion
in the presence of a 2N correlation. The underlying irreducible diagram has
been recently suggested by the authors as a possible candidate to explain the
puzzle of the vector analyzing powers $A_y$ and $iT_{11}$ for nucleon-deuteron
scattering. Herein, we have calculated the elastic neutron-deuteron
differential cross section, $A_y$, $iT_{11}$, $T_{20}$, $T_{21}$, and $T_{22}$
below break-up threshold by accurately solving the Alt-Grassberger-Sandhas
equations with realistic interactions. We have also studied how $A_y$ evolves
below 30 MeV. The results indicate that this new 3NF diagram provides one
possible additional contribution, with the correct spin-isospin structure, for
the explanation of the origin of this puzzle.

</DOC>
<DOC>
<DOCNO> 70399 </DOCNO>
Floquet theory of neutrino oscillations in the earth


  We review the Floquet theory of linear differential equations with periodic
coefficients and discuss its applications to neutrino oscillations in matter of
periodically varying density. In particular, we consider parametric resonance
in neutrino oscillations which can occur in such media, and discuss
implications for oscillations of neutrinos traversing the earth and passing
through the earth's core.

</DOC>
<DOC>
<DOCNO> 152259 </DOCNO>
Quantum delocalization of the electric charge


  The classical Maxwell-Dirac and Maxwell-Klein-Gordon theories admit solutions
of the field equations where the corresponding electric current vanishes in the
causal complement of some bounded region of Minkowski space. This poses the
interesting question of whether states with a similarly well localized charge
density also exist in quantum electrodynamics. For a large family of charged
states, the dominant quantum corrections at spacelike infinity to the
expectation values of local observables are computed. It turns out that certain
moments of the charge density decrease no faster than the Coulomb field in
spacelike directions. In contrast to the classical theory, it is therefore
impossible to define the electric charge support of these states in a
meaningful way.

</DOC>
<DOC>
<DOCNO> 11788 </DOCNO>
Bcc ^4He as a Coherent Quantum Solid: "Super-Solid" ?


  In this work we investigate the quantum nature of bcc $^{4}$He. We show that
it is a solid phase with an Off-Diagonal Long Range Order of coherently
oscillating local electric dipole moments. These dipoles arise from the
correlated zero-point motion of the atoms in the crystal potential, which
oscillate in synchrony so that the dipolar interaction energy is minimized.
This coherent state has a three-component complex order parameter. The
condensation energy of these dipoles in the bcc phase further stabilizes it
over the hcp phase at finite temperatures. This condensation of the dipoles is
not a 'super-solid'. We further show that there can be fermionic excitations of
this ground-state and predict that they form an optic-like branch in the (110)
direction.

</DOC>
<DOC>
<DOCNO> 100694 </DOCNO>
p-Adic and Adelic Free Relativistic Particle


  We consider spectral problem for a free relativistic particle in p-adic and
adelic quantum mechanics. In particular, we found p-adic and adelic
eigenfunctions. Within adelic approach there exist quantum states that exhibit
discrete structure of spacetime at the Planck scale.

</DOC>
<DOC>
<DOCNO> 120695 </DOCNO>
The Distribution of Redshifts in New Samples of Quasi-stellar Objects


  Two new samples of QSOs have been constructed from recent surveys to test the
hypothesis that the redshift distribution of bright QSOs is periodic in
$\log(1+z)$. The first of these comprises 57 different redshifts among all
known close pairs or multiple QSOs, with image separations $\leq$ 10\arcsec,
and the second consists of 39 QSOs selected through their X-ray emission and
their proximity to bright comparatively nearby active galaxies. The redshift
distributions of the samples are found to exhibit distinct peaks with a
periodic separation of $\sim 0.089 $ in $\log(1+z)$ identical to that claimed
in earlier samples but now extended out to higher redshift peaks $z = 2.63,
3.45$ and 4.47, predicted by the formula but never seen before. The periodicity
is also seen in a third sample, the 78 QSOs of the 3C and 3CR catalogues. It is
present in these three datasets at an overall significance level $10^{-5}$ -
$10^{-6}$, and appears not to be explicable by spectroscopic or similar
selection effects. Possible interpretations are briefly discussed.

</DOC>
<DOC>
<DOCNO> 71809 </DOCNO>
CP, T and CPT Symmetries at the Turn of a New Millenium


  After summarizing the status concerning CP violation in 1998 I describe the
exciting developments of the last two years and extrapolate to the future. I
comment on recent lessons about T and CPT invariance maninly from CPLEAR and
emphasize the potential of finding New Physics by analyzing $K_{\mu 3}$ and
charm decays and searching for electric dipole moments.

</DOC>
<DOC>
<DOCNO> 68545 </DOCNO>
Lepton polarization and CP-violating effects in "B -> K^* tau^+ tau^-"


  The most general model independent expressions for the CP-violating
asymmetry, longitudinal, transversal and normal polarizations of leptons are
derived. Application of these general results to the concrete models such as
Standard model and three different types of two Higgs doublet model is
discussed.

</DOC>
<DOC>
<DOCNO> 120330 </DOCNO>
PG 2131+066: A Test of Pre-White Dwarf Asteroseismology


  PG 2131+066 is a composite-spectrum binary with a hot pulsating PG 1159-type
pre-white dwarf and an early M-type main sequence star. Analysis of Whole Earth
Telescope observations of the pulsating pre-white dwarf component provided an
asteroseismological determination of its mass, luminosity, and effective
temperature. These determinations allowed Kawaler et al. (1995) to determine
the distance to this star. In this paper, we refine the asteroseismological
distance determination, and confirm the distance by an independent measurement
to the system via the spectroscopic parallax of the M star. PG 2131+066 was
observed by the HST using the original PC in September 1993. Exposures with
filters F785LP and F555W both showed the companion at a distance of 0.3 arc
seconds. Photometry of the images provides an apparent magnitude for the main
sequence companion of v=18.97+/-0.15, from which we find a distance of 560
(+200 -134) pc. We also recalculated the asteroseismological distance to the
pre-white dwarf using updated models and new spectroscopic constraints from UV
spectra. The new seismological distance is 668 (+78 -83) pc, in satisfactory
agreement with the distance of the secondary star. These results suggest that
this is indeed a physical binary, and that seismological distance determination
may be the best way to determine the distance to the pulsating hot pre-white
dwarf stars.

</DOC>
<DOC>
<DOCNO> 69674 </DOCNO>
$1/m_Q$ and $1/N_c$ Expansions for Excited Heavy Baryons with Light


  The mass spectrum of the L=1 orbitally excited heavy baryons with light
quarks in the spin-flavor symmetric representation is studied by the $1/N_c$
expansion method in the framework of the heavy quark effective theory. The
mixing effect from the baryons in the mixed representation is considered. The
general pattern of the spectrum is predicted which will be verified by the
experiments in the near future. The $1/m_Q$ and SU(3) corrections are also
considered. Mass relations for the baryons $\Lambda_{c1}^{(*)}$,
$\Sigma_{c1}^{(*)}$, $\Xi_{c1}^{(')(*)}$, and $\Omega_{c1}^{(*)}$ are derived.

</DOC>
<DOC>
<DOCNO> 120524 </DOCNO>
HST/WFPC2 and VLA Observations of the Ionized Gas in the Dwarf Starburst


  We present new H alpha and [O III] 5007 narrow band images of the
starbursting dwarf galaxy NGC 4214, obtained with the WFPC2 onboard HST,
together with VLA observations of the same galaxy. The HST images resolve
features down to physical scales of 2-5 pc, revealing several young (<10 Myr)
star forming complexes of various ionized gas morphologies (compact knots,
complete or fragmentary shells) and sizes (10-200 pc). Our results are
consistent with a uniform set of evolutionary trends: The youngest, smaller,
filled regions that presumably are those just emerging from dense star forming
clouds, tend to be of high excitation and are highly obscured. Evolved, larger
shell-like regions have lower excitation and are less extincted due of the
action of stellar winds and supernovae. In at least one case we find evidence
for induced star formation which has led to a two-stage starburst. Age
estimates based on W(H alpha) measurements do not agree with those inferred
from wind-driven shell models of expanding H II regions. The most likely
explanation for this effect is the existence of a 2 Myr delay in the formation
of superbubbles caused by the pressure exerted by the high density medium in
which massive stars are born. We report the detection of a supernova remnant
embedded in one of the two large H II complexes of NGC 4214. The dust in NGC
4214 is not located in a foreground screen but is physically associated with
the warm ionized gas.

</DOC>
<DOC>
<DOCNO> 8825 </DOCNO>
Classical mechanics technique for quantum linear response


  It is shown that the lowest excitation energies of a quantum many-fermion
system in the random phase approximation (RPA) can be obtained by minimizing an
effective classical energy functional. The minimum can be found very
efficiently using generalized Lanczos technique. Application of the new
technique to molecular spectra allows to compute excited states at the expense
comparable to the ground-state calculations. As an example, the first-principle
RPA excitation spectrum of C60 molecule is computed taking into account all 240
valence electrons in the full valence space of the molecule. The results match
linear absorption experiment within percents.

</DOC>
<DOC>
<DOCNO> 12938 </DOCNO>
Capacity of multivariate channels with multiplicative noise: I.Random


  We study memoryless, discrete time, matrix channels with additive white
Gaussian noise and input power constraints of the form $Y_i = \sum_j H_{ij} X_j
+ Z_i$, where $Y_i$ ,$X_j$ and $Z_i$ are complex, $i=1..m$, $j=1..n$, and $H$
is a complex $m\times n$ matrix with some degree of randomness in its entries.
The additive Gaussian noise vector is assumed to have uncorrelated entries. Let
$H$ be a full matrix (non-sparse) with pairwise correlations between matrix
entries of the form $ E[H_{ik} H^*_{jl}] = {1\over n}C_{ij} D_{kl} $, where
$C$,$D$ are positive definite Hermitian matrices. Simplicities arise in the
limit of large matrix sizes (the so called large-N limit) which allow us to
obtain several exact expressions relating to the channel capacity. We study the
probability distribution of the quantity $ f(H) = \log \det (1+P H^{\dagger}S
H) $. $S$ is non-negative definite and hermitian, with $Tr S=n$. Note that the
expectation $E[f(H)]$, maximised over $S$, gives the capacity of the above
channel with an input power constraint in the case $H$ is known at the receiver
but not at the transmitter. For arbitrary $C$,$D$ exact expressions are
obtained for the expectation and variance of $f(H)$ in the large matrix size
limit. For $C=D=I$, where $I$ is the identity matrix, expressions are in
addition obtained for the full moment generating function for arbitrary
(finite) matrix size in the large signal to noise limit. Finally, we obtain the
channel capacity where the channel matrix is partly known and partly unknown
and of the form $\alpha I+ \beta H$, $\alpha,\beta$ being known constants and
entries of $H$ i.i.d. Gaussian with variance $1/n$. Channels of the form
described above are of interest for wireless transmission with multiple
antennae and receivers.

</DOC>
<DOC>
<DOCNO> 170272 </DOCNO>
Quantum strategies of quantum measurement


  In classical Monty Hall problem, one player can always win with probability
2/3. We generalize the problem to the quantum domain and show that a fair
two-party zero-sum game can be carried out if the other player is permitted to
adopt quantum measurement strategy.

</DOC>
<DOC>
<DOCNO> 121210 </DOCNO>
An HI Survey of the Great Attractor Region


  A blind HI survey using the Parkes telescope at |b|<5 deg, 300 deg < l < 332
deg has so far revealed 305 galaxies, most of which were previously unknown.
These galaxies are used to map out the distribution of filaments and voids out
to 10000 km/s. A preliminary measurement of the galaxy overdensity suggests
only a moderate overdensity is present, and that the excess mass (above the
background density) is ~2.10^{15}.Omega.M(sun). This is below the mass
predicted in POTENT reconstructions of the local velocity field, and implies
that the `Great Attractor' (GA) is not as massive as these reconstructions
indicate, or does not lie hidden in the region investigated.

</DOC>
<DOC>
<DOCNO> 99668 </DOCNO>
Right eigenvalue equation in quaternionic quantum mechanics


  We study the right eigenvalue equation for quaternionic and complex linear
matrix operators defined in n-dimensional quaternionic vector spaces. For
quaternionic linear operators the eigenvalue spectrum consists of n complex
values. For these operators we give a necessary and sufficient condition for
the diagonalization of their quaternionic matrix representations. Our
discussion is also extended to complex linear operators, whose spectrum is
characterized by 2n complex eigenvalues. We show that a consistent analysis of
the eigenvalue problem for complex linear operators requires the choice of a
complex geometry in defining inner products. Finally, we introduce some
examples of the left eigenvalue equations and highlight the main difficulties
in their solution.

</DOC>
<DOC>
<DOCNO> 120764 </DOCNO>
Quasi-periodic oscillations and noise in neutron star and black-hole


  Before the launch of the Rossi X-ray Timing Explorer (RXTE) satellite, the
differences in the rapid X-ray variability between the two main types of
neutron star binaries (i.e., the Z and atoll sources) could be explained by
invoking different mass accretion rates and magnetic field strengths. However,
the results obtained with RXTE now show that these systems are more similar
than previously thought and although differences in mass accretion rate are
still likely, the differences in the magnetic field strength have become
questionable. The great similarities between the neutron star systems and the
black-hole candidates at low mass accretion rates also point towards a similar
origin of their timing phenomena indicating that the presence or absence of a
solid surface, a magnetic field, or an event horizon do not play a significant
role in the production mechanisms for the rapid X-ray variability.

</DOC>
<DOC>
<DOCNO> 13499 </DOCNO>
The origin of high transport spin polarization in La$_{0.7}$Sr$_{0.3}


  Using the point contact Andreev reflection technique, we have carried out a
systematic study of the spin polarization in the colossal magnetoresistive
manganite, La$_{0.7}$Sr$_{0.3}$MnO$_{3}$} (LSMO). Surprisingly, we observed a
significant increase in the current spin polarization with the residual
resistivity. This counterintuitive trend can be understood as a transition from
ballistic to diffusive transport in the contact. Our results strongly suggest
that LSMO does have minority spin states at the Fermi level. However, since its
current spin polarization is much higher than that of the density of states,
this material can mimic the behavior of a true half-metal in transport
experiments. Based on our results we call this material a {\it transport}
half-metal.

</DOC>
<DOC>
<DOCNO> 123145 </DOCNO>
UVES-VLT Observations of the OIII Bowen Lines in RR Tel


  The exceptional resolution of UVES has allowed the detection of weak spectral
features and the separation of components in blended lines. The intensities of
all of the OIII fluorescence lines produced by the O1, O3 and other channels,
including the 5592 Angstrom charge-exchange line, have been measured and their
ratios compared with models.

</DOC>
<DOC>
<DOCNO> 11292 </DOCNO>
Superconductivity in the SU(N) Anderson Lattice at U=\infty


  We present a mean-field study of superconductivity in a generalized N-channel
cubic Anderson lattice at U=\infty taking into account the effect of a
nearest-neighbor attraction J. The condition U=\infty is implemented within the
slave-boson formalism considering the slave bosons to be condensed. We consider
the $f$-level occupancy ranging from the mixed valence regime to the Kondo
limit and study the dependence of the critical temperature on the various model
parameters for each of three possible Cooper pairing symmetries (extended s,
d-wave and p-wave pairing) and find interesting crossovers. It is found that
the d- and p- wave order parameters have, in general, very similar critical
temperatures. The extended s-wave pairing seems to be relatively more stable
for electronic densities per channel close to one and for large values of the
superconducting interaction J.

</DOC>
<DOC>
<DOCNO> 151321 </DOCNO>
Chern-Simons terms and the Three Notions of Charge


  In theories with Chern-Simons terms or modified Bianchi identities, it is
useful to define three notions of either electric or magnetic charge associated
with a given gauge field. A language for discussing these charges is introduced
and the properties of each charge are described. `Brane source charge' is gauge
invariant and localized but not conserved or quantized, `Maxwell charge' is
gauge invariant and conserved but not localized or quantized, while `Page
charge' conserved, localized, and quantized but not gauge invariant. This
provides a further perspective on the issue of charge quantization recently
raised by Bachas, Douglas, and Schweigert.

</DOC>
<DOC>
<DOCNO> 121274 </DOCNO>
The Physical Relation between Age and Metallicity in Galaxies


  We present unified chemical and spectrophotometric evolutionary synthesis
models that allow to describe composite stellar populations in a chemically
consistent way. Keeping track of the ISM abundance at birth of each star and
using sets of input physics (stellar yields, tracks, spectra) for different
metallicities we account for the increasing initial metallicity of successive
stellar generations. For any galaxy type its Star Formation History determines
the physical relation between the ages and metallicities of its stars. As
compared to models using solar metallicity input physics only, differences are
significant, both for the ISM enrichment evolution and for the
spectrophotometric evolution, and they increase with lookback time. Results are
used to interprete Damped Ly$\alpha$ Absorbers. Knowledge of the chemical
evolution of the ISM allows to predict abundances of stars, star clusters, and
tidal dwarf galaxies that may form when spirals merge at any redshift.

</DOC>
<DOC>
<DOCNO> 84223 </DOCNO>
On Fine's resolution of the EPR-Bell problem


  In the real spin-correlation experiments the detection/emission inefficiency
is usually ascribed to independent random detection errors, and treated by the
"enhancement hypothesis". In Fine's "prism model" the detection inefficiency is
an effect not only of the random errors in the analyzer + detector equipment,
but is also the manifestation of a pre-settled (hidden) property of the
particles.

</DOC>
<DOC>
<DOCNO> 120878 </DOCNO>
Stellar Populations and Surface Brightness Fluctuations: New


  We examine the use of surface brightness fluctuations (SBF) for both stellar
population and distance studies. New V-band SBF data are reported for five
Fornax cluster galaxies and combined with literature data to define a new
V-band SBF distance indicator. We use new stellar population models, based on
the latest Padua isochrones transformed empirically to the observational plane,
to predict SBF magnitudes and integrated colours for a wide range of population
ages and metallicities. We examine the sensitivity of the predictions to
changes in the isochrones, transformations, and IMF. The new models reproduce
the SBF data for globular clusters fairly well, especially if higher
metallicity globulars are younger. The models also give a good match to the
"fluctuation colors" of elliptical galaxies. In order to obtain theoretical
calibrations of the SBF distance indicators, we combine our single-burst models
into composite population models. These models reproduce the observed behavior
of the SBF magnitudes as a function of stellar population parameters, including
the steep colour dependence found for HST/WFPC2 F814W SBF data. Because the
theoretical SBF calibrations are fairly sensitive to uncertain details of
stellar evolution, the empirical calibrations are more secure. However, the
sensitivity of SBF to these finer details potentially makes it a powerful
constraint for stellar evolution and population synthesis. [abbridged]

</DOC>
<DOC>
<DOCNO> 69099 </DOCNO>
Supersymmetry for Flavors


  An understanding of the lepton masses within the framework of SUSY is
presented. A family symmetry is introduced. Sneutrino VEV breaks this symmetry.
The tau mass is due to the Higgs VEV, and muon mass purely from the sneutrino
VEV. A viable model is constructed, which predicts (1-10) MeV tau-neutrino.

</DOC>
<DOC>
<DOCNO> 150861 </DOCNO>
N=4 Super Yang-Mills Low-Energy Effective Action at Three and Four Loops


  We investigate the low-energy effective action in N=4 super Yang-Mills theory
with gauge group SU(n) spontaneously broken down to its maximal torus. Using
harmonic superspace technique we prove an absence of any three- and four-loop
corrections to non-holomorphic effective potential depending on N=2 superfield
strengths. A mechanism responsible for vanishing arbitrary loop corrections to
low-energy effective action is discussed.

</DOC>
<DOC>
<DOCNO> 122574 </DOCNO>
A search for new gamma Doradus stars in the Geneva photometric database


  We present a study of selected potential gamma Doradus stars observed in the
Geneva photometric system. Eleven stars were monitored at least during the last
year of functioning of the 70 cm Swiss telescope at La Silla, leading to about
one thousand photometric measurements and permitting a detailed analysis of
these stars. After the analysis, five stars are thought to be constant stars.
We report three new gamma Doradus stars. A spectroscopic campaign has been
started at La Silla with the new 1m20 Swiss telescope, equipped with the
spectrograph CORALIE, of which we show the results for the selected stars.

</DOC>
<DOC>
<DOCNO> 170756 </DOCNO>
Idealization Second Quantization of Composite Particles


  A practical method is developed to deal with the second quantization of the
many-body system containing the composite particles. In our treatment, the
modes associated with composite particles are regarded approximately as
independent ones compared with those of unbound particles. The field operators
of the composite particles thus arise naturally in the second quantization
Hamiltonian. To be emphasized, the second quantization Hamiltonian has the
regular structures which correspond clearly to different physical processes.

</DOC>
<DOC>
<DOCNO> 122918 </DOCNO>
Heating the Quiet Corona by Nanoflares: Evidence and Problems


  The content of coronal material in the quiet Sun is not constant as soft
X-ray and high-temperature EUV line observations have shown. New material,
probably heated and evaporated from the chromosphere is occasionally injected
even in the faintest parts above the magnetic network cell interiors. Assuming
that the smaller events follow the pattern of the well observed larger ones, we
estimate the total energy input. Various recent analyses are compared and
discussed. The results using similar EUV data from EIT/SOHO and TRACE basically
agree on the power-law exponent when the same method is used. The most serious
deviations are in the number of nanoflares per energy unit and time unit. It
can be explained only partially by different thresholds for flare detection.

</DOC>
<DOC>
<DOCNO> 40350 </DOCNO>
Recent Results on Charm Photoproduction


  Photoproduction of $D_s^{\pm}$ mesons has been measured in the ZEUS detector
at HERA and compared with predictions of NLO pQCD calculations. The ratio of
$D_s^{*\pm}$ to $D^{*\pm}$ cross sections has been compared to results from
$e^{+}e^{-}$ experiments. Orbitally excited P-wave charm mesons have been
observed in the $D^{*\pm}\pi^{\mp}$ final state. The fraction of $D^{*\pm}$ 's
originating from these mesons has been calculated and compared with that from
$e^{+}e^{-}$ interactions. No evidence for radially excited mesons decaying to
$D^{*\pm}\pi^{+}\pi^{-}$ was found. The inelastic production of J/$\psi$ mesons
has been measured and compared to LO and NLO pQCD predictions.

</DOC>
<DOC>
<DOCNO> 174480 </DOCNO>
Internal conversion coefficients for superheavy elements


  The internal conversion coefficients (ICC) were calculated for all atomic
subshells of the elements with 104<=Z<=126, the E1...E4, M1...M4
multipolarities and the transition energies between 10 and 1000 keV. The atomic
screening was treated in the relativistic Hartree-Fock-Slater model. The Tables
comprising almost 90000 subshell and total ICC were recently deposited at LANL
preprint server.

</DOC>
<DOC>
<DOCNO> 178876 </DOCNO>
Symmetry-Unrestricted Skyrme-Hartree-Fock-Bogoliubov Calculations for


  By performing fully 3D symmetry-unrestricted Skyrme-Hartree-Fock-Bogoliubov
calculations, we discuss shape coexistence and possibility of exotic
deformations simultaneously breaking the reflection and axial symmetries in
proton-rich N=Z nuclei: 64Ge, 68Se, 72Kr, 76Sr, 80Zr and 84Mo. Results of
calculation indicate that the oblate ground state of 68Se is extremely soft
against the Y33 triangular deformation, and that the low-lying spherical
minimum coexisting with the prolate ground state in 80Zr may be unstable
against the Y32 tetrahedral deformation.

</DOC>
<DOC>
<DOCNO> 119851 </DOCNO>
Ginzburg-Landau equations for superconducting quark matter in neutron


  We investigate magnetic properties of color superconducting quark matter
within a Ginzburg-Landau approach. The simultaneous coupling of the quark
fields to gluonic and electromagnetic gauge fields leads to rotated
electromagnetism with a massive (Higgsed) and a massless photon-gluon field. We
derive the Ginzburg-Landau equations for superconducting quark matter taking
into account the rotated electromagnetism in the general case when the rotation
angle is an arbitrary function of the coordinates. We solve these equations for
an isolated vortex in superconducting quark matter. We obtain a solution for
the magnetic and gluomagnetic fields and expressions for the calculation of the
penetration depth and the quantized magnetic flux in quark matter. For this
case we have demonstrated that the occurence of electric and color Meissner
currents is a consequence of the color superconducting state of quark matter.

</DOC>
<DOC>
<DOCNO> 70971 </DOCNO>
Cosmic Ray Air Shower Characteristics in the Framework of the


  The purpose of this paper is twofold: first we want to introduce a new type
of hadronic interaction model (NEXUS), which has a much more solid theoretical
basis as, for example, presently used models like QGSJET and VENUS, and ensures
therefore a much more reliable extrapolation towards high energies. Secondly,
we want to promote an extensive air shower (EAS) calculation scheme, based on
cascade equations rather than explicit Monte Carlo simulations, which is very
accurate in calculations of main EAS characteristics and extremely fast
concerning computing time. We employ the NEXUS model to provide the necessary
data on particle production in hadron-air collisions and present the average
EAS characteristics for energies 10^14 - 10^17 eV. The experimental data of the
casa-blanka group are analyzed in the framework of the new model.

</DOC>
<DOC>
<DOCNO> 70123 </DOCNO>
The KM phase in semi-realistic heterotic orbifold models


  In string-inspired semi-realistic heterotic orbifolds models with an
anomalous $U(1)_X$, a nonzero Kobayashi-Masakawa (KM) phase is shown to arise
generically from the expectation values of complex scalar fields, which appear
in nonrenormalizable quark mass couplings. Modular covariant nonrenormalizable
superpotential couplings are constructed. A toy $Z_3$ orbifold model is
analyzed in some detail. Modular symmetries and orbifold selection rules are
taken into account and do not lead to a cancellation of the KM phase. We also
discuss attempts to obtain the KM phase solely from renormalizable
interactions.

</DOC>
<DOC>
<DOCNO> 123178 </DOCNO>
Cooling a Hot Disk Around a Supermassive Black Hole by a Star


  If a supermassive black hole resides in the centers of galaxies, there are
several effects expected to be observed. It is likely that accretion disks are
around the supermassive black hole. Stellar interactions with the accretion
flows around the supermassive black hole play a role in that an flying-by star
may cool a hot accretion disk as a result of Comptonization. It is shown that
the Comptonization of the stellar emission will take place in a hot accretion
disk such as the ADAFs around the supermassive black hole and become a
relatively important source of the accretion disk cooling when the mass
accretion rate is low, and stars are passing outer parts of the hot accretion
disk. We suggest that such a stellar cooling can be observed in the radio
frequency regime since synchrotron luminosity of the ADAFs depends strongly on
the electron temperature and occurs much more frequently than a tidal
disruption event.

</DOC>
<DOC>
<DOCNO> 71317 </DOCNO>
Off-shell d=5 Supergravity coupled to Matter-Yang-Mills System


  We present an off-shell formulation of matter-Yang-Mills system coupled to
supergravity in five dimensional space-time. We give an invariant action for
the general system of vector multiplets and hypermultiplets coupled to
supergravity as well as the supersymmetry transformation rules. All the
auxiliary fields are kept un-eliminated so that the supersymmetry
transformation rules remain unchanged even when the action is changed.

</DOC>
<DOC>
<DOCNO> 83073 </DOCNO>
Evolution of differentiated expression patterns in digital organisms


  We investigate the evolutionary processes behind the development and
optimization of multiple threads of execution in digital organisms using the
avida platform, a software package that implements Darwinian evolution on
populations of self-replicating computer programs. The system is seeded with a
linearly executed ancestor capable only of reproducing its own genome, whereas
its underlying language has the capacity for multiple threads of execution
(i.e., simultaneous expression of sections of the genome.) We witness the
evolution to multi-threaded organisms and track the development of distinct
expression patterns. Additionally, we examine both the evolvability of
multi-threaded organisms and the level of thread differentiation as a function
of environmental complexity, and find that differentiation is more pronounced
in complex environments.

</DOC>
<DOC>
<DOCNO> 116789 </DOCNO>
Unconditionally secure quantum bit commitment is simply possible


  Mayers, Lo and Chau proved unconditionally secure quantum bit commitment is
impossible. It is shown that their proof is valid only for a particular model
of quantum bit commitment encoding, in general it does not hold good. A
different model of unconditionally secure quantum bit commitment - both
entanglement and disentanglement-based - is presented. Even cheating can be
legally proved with some legal evidences. Unconditionally secure quantum bit
commitment can be established on the top of unconditionally secure quantum coin
tossing, which is also claimed to be two-way impossible.

</DOC>
<DOC>
<DOCNO> 121449 </DOCNO>
Discovery of the Orbit of the Transient X ray Pulsar SAX J2103.5+4545


  Using X-ray data from the Rossi X-Ray Timing Explorer (RXTE), we carried out
pulse timing analysis of the transient X-ray pulsar SAX J2103.5+4545. An
outburst was detected by All Sky Monitor (ASM) October 25 1999 and reached a
peak X-ray brightness of 27 mCrab October 28. Between November 19 and December
27, the RXTE/PCA carried out pointed observations which provided us with pulse
arrival times. These yield an eccentric orbit (e= 0.4 \pm 0.2) with an orbital
period of 12.68 \pm 0.25 days and light travel time across the projected
semimajor axis of 72 \pm 6 sec. The pulse period was measured to be 358.62171
\pm 0.00088 s and the spin-up rate (2.50 \pm 0.15) \times 10^{-13} Hz s^{-1}.
The ASM data for the February to September 1997 outburst in which BeppoSAX
discovered SAX J2103.5+4545 (Hulleman, in't Zand and Heise 1998) are modulated
at time scales close to the orbital period. Folded light curves of the 1997 ASM
data and the 1999 PCA data are similar and show that the intensity increases at
periastron passages.

</DOC>
<DOC>
<DOCNO> 121965 </DOCNO>
Temperature Map of the Virgo Cluster of Galaxies Observed with ASCA


  The temperature distribution of the intracluster medium (ICM) in the Virgo
cluster of galaxies has been derived from extensive mapping observations with
ASCA covering an area of 19 deg^2. In the spectral analysis, the inner region
within a radius of ~60' from M87 is characterized by an ICM temperature of kT
\~2.5 keV with little variation. On the other hand, the outer regions indicate
significant variation of the temperature with an amplitude of about 1 keV. The
temperature map was produced from the hardness ratio (H.R.) values with a
resolution of about 5'. Besides the previously reported hot region with kT > 4
keV between M87 and M49, several hot regions with kT = 3-4 keV are detected in
the cluster outskirts. The auto-correlation function for the H.R. variation
shows that the temperature variation is correlated within a size of about 300
kpc, suggesting that gas blobs falling in the Virgo cluster have a typical size
of groups of galaxies. A correlation with the velocity dispersion of member
galaxies shows that only the north-west region indicates an unusually large
beta_spec value of 2-4. The upper limit for extended non-thermal emission in
the Virgo cluster is obtained to be L_X ~9 x 10^41 ergs/s in the 2 - 10 keV
band. We discuss that these features consistently indicate that the Virgo
cluster is in a relatively early stage of the cluster evolution.

</DOC>
<DOC>
<DOCNO> 119812 </DOCNO>
X-ray emission from Seyfert 2 galaxies with optical polarized broad


  We analyze the 0.5-10 keV spectra of six Seyfert 2 galaxies observed with the
X-ray satellite ASCA: Mrk 3, Mrk 348, Mrk 1210, Mrk 477, NGC 7212, and Was 49b.
These galaxies were selected based on their possession of optical polarized
broad lines. In the 2-10 keV band, their spectra are heavily absorbed, with
2-10 keV absorption-corrected X-ray luminosities ranging from 10^{42} to
10^{43} erg/s. The observed X-ray emission is generally only about one tenth
that predicted based on their known infrared and H_beta luminosities. This
apparent X-ray weakness can be understood if a considerable fraction of the
nuclear activity is completely blocked from view by thick matter along our line
of sight to the nucleus.
  All of these galaxies possess significant soft X-ray emission whose origin
appears to be scattered light from their nuclear emission. Based on this
hypothesis, we estimate a typical scattering efficiency for X-rays to be about
10%. This efficiency is larger than the few % found for ordinary Seyfert 2
galaxies with no report of optical polarized broad lines. A large scattering
efficiency is best explained by an apparent weakness of the hard X-ray
luminosity rather than unusually strong scattered light in the soft band. The
difference of the apparent weakness is probably associated with viewing angle.

</DOC>
<DOC>
<DOCNO> 178781 </DOCNO>
Partial Dynamical Symmetry in a Fermionic Many-Body System


  The concept of partial symmetry is introduced for an interacting fermion
system. The associated Hamiltonians are shown to be closely related to a
realistic nuclear quadrupole-quadrupole interaction. An application to $^{12}$C
is presented.

</DOC>
<DOC>
<DOCNO> 152110 </DOCNO>
Patterns of Broken Chiral Symmetry in Quantum Chromodynamics


  We establish that in Quantum Chromodynamics (QCD) at zero temperature,
SU_(L+R)(N_F) exhibits the vector mode conjectured by Georgi and
SU_(L-R)(N_F)is realized in either the Nambu-Goldstone mode or else the
axial-vector charge is also screened from view at infinity. The Wigner-Weyl
mode is ruled out unless the beta function in QCD develops an infrared stable
zero.

</DOC>
<DOC>
<DOCNO> 123143 </DOCNO>
Discovery of a 9-s X-Ray Pulsar, AX J0049-732, in the Small Magellanic


  We report the ASCA discovery of a new X-ray pulsar, AX J0049-732, in the
Small Magellanic Cloud (SMC). The pulse shape is sinusoidal with a barycentric
period of 9.1320 +/- 0.0004 s. The X-ray spectrum was fitted by an absorbed
power-law model with a photon index of ~0.6 and a column density of ~1.3e22
cm^-2. An unabsorbed flux in the 0.7-10.0 keV was estimated to be ~8e-13 erg
cm^-2 s^-1 corresponding to the X-ray luminosity of ~4e35 erg s^-1 at the SMC
distance of 62 kpc.

</DOC>
<DOC>
<DOCNO> 178685 </DOCNO>
Nucleon form factors in the canonically quantized Skyrme model


  The explicit expressions for the electric, magnetic, axial and induced
pseudoscalar form factors of the nucleons are derived in the {\it ab initio}
quantized Skyrme model. The canonical quantization procedure ensures the
existence of stable soliton solutions with good quantum numbers. The form
factors are derived for representations of arbitrary dimension of the SU(2)
group. After fixing the two parameters of the model, $f_\pi$ and $e$, by the
empirical mass and electric mean square radius of the proton, the calculated
electric and magnetic form factors are fairly close to the empirical ones,
whereas the the axial and induced pseudoscalar form factors fall off too slowly
with momentum transfer.

</DOC>
<DOC>
<DOCNO> 122600 </DOCNO>
XMM- Newton Observation of the Coma Galaxy Cluster: The temperature


  We present a temperature map and a temperature profile of the central part (r
< 20' or 1/4 virial radius) of the Coma cluster. We combined 5 overlapping
pointings made with XMM/EPIC/MOS and extracted spectra in boxes of 3.5' X 3.5'.
The temperature distribution around the two central galaxies is remarkably
homogeneous (r<10'), contrary to previous ASCA results, suggesting that the
core is actually in a relaxed state. At larger distance from the cluster center
we do see evidence for recent matter accretion. We confirm the cool area in the
direction of NGC 4921, probably due to gas stripped from an infalling group. We
find indications of a hot front in the South West, in the direction of NGC4839,
probably due to an adiabatic compression.

</DOC>
<DOC>
<DOCNO> 67893 </DOCNO>
Preasymptotic effects in beauty decays


  Large preasymptotic effects in beauty decays have been found using
heavy-quark and SU(3) symmetry, as well as experimental data on charmed
hyperons. Contrary to rather uniform beauty-meson lifetimes, a much larger
spread of beauty-baryon lifetimes is predicted. However, it is highly unlikely
that, theoretically, the $ \tau(\Lambda_b)/\tau(B_d^0) $ ratio, which at
present deviates more than $1\sigma$ from the experimental result, can be
lowered below 0.9.

</DOC>
<DOC>
<DOCNO> 122708 </DOCNO>
Hiden Star Formation: The Ultraviolet Perspective


  Many recent estimates of the star formation rate density at high redshift
rely on rest-frame ultraviolet (UV) data. These are highly sensitive to dust
absorption. Applying a correlation between the far-infrared (FIR) to UV flux
ratio and UV color found in a local starbursts to galaxy samples out to z ~ 3,
one can account for most of the FIR background. However, the correlation is
based on a sample that does not include the most extreme starbursts, Ultra
Luminous Infrared Galaxies (ULIGs). Our new UV images of ULIGs show that their
FIR fluxes are underpredicted by this correlation by factors ranging from 7 to
70. We discuss how ULIGs compare to the various types of high-z galaxies:
sub-mm sources, Lyman Break Galaxies, and Extremely Red Objects.

</DOC>
<DOC>
<DOCNO> 70851 </DOCNO>
Scalar meson spectroscopy: achievements and traps


  Interactions in three coupled channels: pi-pi, K-anti K and sigma-sigma have
been investigated in a wide two-pion effective mass region from the pi-pi
threshold up to 1600 MeV. Analytical structure of amplitudes in all channels
has been studied. It was shown that its knowledge is necessary to understand
spectrum of scalar mesons and their nature.

</DOC>
<DOC>
<DOCNO> 13007 </DOCNO>
Pairing fluctuations and pseudogaps in the attractive Hubbard model


  The two-dimensional attractive Hubbard model is studied in the weak to
intermediate coupling regime by employing a non-perturbative approach. It is
first shown that this approach is in quantitative agreement with Monte Carlo
calculations for both single-particle and two-particle quantities. Both the
density of states and the single-particle spectral weight show a pseudogap at
the Fermi energy below some characteristic temperature T*, also in good
agreement with quantum Monte Carlo calculations. The pseudogap is caused by
critical pairing fluctuations in the low-temperature renormalized classical
regime $\omega < T$ of the two-dimensional system. With increasing temperature
the spectral weight fills in the pseudogap instead of closing it and the
pseudogap appears earlier in the density of states than in the spectral
function. Small temperature changes around T* can modify the spectral weight
over frequency scales much larger than temperature. Several qualitative results
for the s-wave case should remain true for d-wave superconductors.

</DOC>
<DOC>
<DOCNO> 117740 </DOCNO>
Outbursts of EX Hydrae: mass-transfer events or disc instabilities?


  We present the 45-yr record of EX Hya's lightcurve and discuss the
characteristics of its 15 observed outbursts. We then concentrate on the 1998
outburst, reporting the first outburst X-ray observations. We discover an X-ray
beat-cycle modulation, indicating that an enhanced accretion stream couples
directly with the magnetosphere in outburst, confirming our previous
prediction. Optical eclipse profiles late in outburst show that the visible
light is dominated by an enhanced mass-transfer stream overflowing the
accretion disc. We are uncertain whether the enhanced mass transfer is
triggered by a disc instability, or by some other cause. While in outburst, EX
Hya shows some of the characteristics of SW Sex stars.

</DOC>
<DOC>
<DOCNO> 69279 </DOCNO>
Muons from strangelets


  The hypothesis is discussed that muon bundles of extremaly high multiplicity
observed recently by ALEPH detector (in the dedicated cosmic-ray run) can
originate from the strangelets colliding with the atmosphere.

</DOC>
<DOC>
<DOCNO> 7637 </DOCNO>
Circularly polarized light emission in scanning tunneling microscopy of


  Light is produced when a scanning tunneling microscope is used to probe a
metal surface. Recent experiments on cobalt utilizing a tungsten tip found that
the light is circularly polarized; the sense of circular polarization depends
on the direction of the sample magnetization, and the degree of polarization is
of order 10 %. This raises the possibility of constructing a magnetic
microscope with very good spatial resolution. We present a theory of this
effect for iron and cobalt and find a degree of polarization of order 0.1 %.
This is in disagreement with the experiments on cobalt as well as previous
theoretical work which found order of magnitude agreement with the experimental
results. However, a recent experiment on iron showed 0.0 ${\pm}$2 %. We predict
that the use of a silver tip would increase the degree of circular polarization
for a range of photon energies.

</DOC>
<DOC>
<DOCNO> 69303 </DOCNO>
Flavour Stability of the Chiral Vacuum and Scalar Meson Dynamics


  Previous work relating the flavour variation of the chiral order parameters
$F_\pi$, $<\bar u u>$ and S-wave scattering data, based on chiral sum rules and
chiral perturbation theory at order $p^4$, is extended to include $O(p^6)$
corrections. The finding of a significant decrease of these order parameters,
particularly $<\bar u u>$, with the number of flavours increasing from $N_F=2$
to $N_F=3$ is confirmed, modulo an assumption on the convergence of the chiral
expansion. The connection between scalar resonance physics and the phase
structure of the chiral vacuum is also illustrated on the basis of the linear
sigma-model. We allow for a very general symmetry breaking sector compatible
with softness. The result depends strongly on the input scalar meson masses, in
particular, on the presence, or not, of a light sigma.}

</DOC>
<DOC>
<DOCNO> 118852 </DOCNO>
Bulk viscosity in superfluid neutron star cores. I. Direct Urca


  The bulk viscosity of the neutron star matter due to the direct Urca
processes involving nucleons, electrons and muons is studied taking into
account possible superfluidity of nucleons in the neutron star cores. The cases
of singlet-state pairing or triplet-state pairing (without and with nodes of
the superfluid gap at the Fermi surface) of nucleons are considered. It is
shown that the superfluidity may strongly reduce the bulk viscosity. The
practical expressions for the superfluid reduction factors are obtained. For
illustration, the bulk viscosity is calculated for two models of dense matter
composed of neutrons, protons,electrons and muons. The presence of muons
affects the bulk viscosity due to the direct Urca reactions involving electrons
and produces additional comparable contribution due to the direct Urca
reactions involving muons. The results can be useful for studying damping of
vibrations of neutron stars with superfluid cores.

</DOC>
<DOC>
<DOCNO> 39725 </DOCNO>
Partial Wave Analysis of $J/\psi \to \gamma (K^{\pm}K_S^0\pi^{\mp})$


  BES data on $J/\psi \to \gamma (K^{\pm} K_S^0 \pi^{\mp})$ are presented.
There is a strong peak due to $\eta(1440)/\iota$, which is fitted with a
Breit-Wigner amplitude with $s$-dependent widths for decays to $K^*K$, $\kappa
K$, $\eta \pi\pi$ and $\rho\rho$; $\kappa$ refers to the $K\pi$ S-wave. At a
$K\bar{K}\pi$ mass of $\sim 2040$ MeV, there is a second peak with width $\sim
400$ MeV; $J^P = 0^-$ is preferred over $1^+$ and $2^-$ respectively by 5.2 and
6.8 standard deviations. It is a possible candidate for a $0^-$ $s\bar sg$
hybrid partner of $\pi(1800)$.

</DOC>
<DOC>
<DOCNO> 9617 </DOCNO>
Static and dynamic coupling transitions of vortex lattices in disordered


  We use three-dimensional molecular dynamics simulations of magnetically
interacting pancake vortices to study vortex matter in disordered, highly
anisotropic materials such as BSCCO. We observe a sharp 2D-3D transition from
vortex lines to decoupled pancakes as a function of relative interlayer
coupling strength, with an accompanying large increase in the critical current
remniscent of a second peak effect. We find that decoupled pancakes, when
driven, simultaneously recouple and order into a crystalline-like state at high
drives. We construct a dynamic phase diagram and show that the dynamic
recoupling transition is associated with a double peak in dV/dI.

</DOC>
<DOC>
<DOCNO> 9898 </DOCNO>
A proper ballistic calculation of tunneling conductance for real


  Employing an ab initio Screened Korringa-Kohn-Rostoker (SKKR) band structure
method for a metal-vacuum-metal junction, we find that the tunnel conductance
is different when it is calculated across the barrier and far from it. We
attribute this difference to an artefact of the ballistic approach which
overestimates the role of specular reflections, and its inability to pick up
contributions from localized interface states. To reconcile the ballistic
approach with experiment, we propose that the tunnel conductance should be
calculated as if it is measured directly across the barrier. In this case the
predicted tunneling magnetoresistance is larger.

</DOC>
<DOC>
<DOCNO> 151608 </DOCNO>
A Small Cosmological Constant and Backreaction of Non-Finetuned


  We include the backreaction on the warped geometry induced by non-finetuned
parameters for a recently proposed mechanism to obtain an exponentially small
cosmological constant \Lambda_4. It is shown that by separating two
domain-walls by a distance 2l the cosmological constant still appears
exponentially suppressed with suppression-length l. Thus no huge hierarchy is
required to obtain a realistic \Lambda_4. Moreover, we find a smooth connection
to the limit with finetuned parameters.

</DOC>
<DOC>
<DOCNO> 118373 </DOCNO>
RBSC-NVSS Sample. I. Radio and Optical Identifications of a Complete


  We cross-identified the ROSAT Bright Source Catalog (RBSC) and the NRAO VLA
Sky Survey (NVSS) to construct the RBSC-NVSS sample of the brightest X-ray
sources (>= 0.1 counts/s or ~1E-12 ergs/cm/cm/s in the 0.1-2.4 keV band) that
are also radio sources (S >= 2.5 mJy at 1.4 GHz) in the 7.8 sr of extragalactic
sky with |b| > 15 degrees. and delta > -40 degrees. The sky density of NVSS
sources is low enough that they can be reliably identified with RBSC sources
having average rms positional uncertainties = 10 arcsec. We used the more
accurate radio positions to make reliable X-ray/radio/optical identifications
down to the POSS plate limits. We obtained optical spectra for many of the
bright identifications lacking published redshifts. The resulting X-ray/radio
sample is unique in its size (N ~ 1500 objects), composition (a mixture of
nearly normal galaxies, Seyfert galaxies, quasars, and clusters), and low
average redshift (<z> ~ 0.1).

</DOC>
<DOC>
<DOCNO> 118716 </DOCNO>
Cosmic Statistics through Weak Lenses


  Many recent studies have demonstrated that scaling arguments, such as the
so-called hierarchical {\em ansatz}, are extremely useful in understanding the
statistical properties of weak gravitational lensing. This is especially true
on small angular scales (i.e. at high resolution), where the usual perturbative
calculations of matter clustering no longer apply. We build on these studies in
order to develop a complete picture of weak lensing at small smoothing angles.
In particular, we study the full probability distribution function, bias and
other multipoint statistics for the ``hot spots'' of the convergence field
induced by weak lensing, and relate these to the statistics of overdense
regions in underlying mass distribution. It is already known that weak lensing
can constrain the background geometry of the Universe, but we further show that
it can also provide valuable information about the statistics of collapsed
objects and the physics of collisionless clustering. Our results are
particularly important for future observations which will, at least initially,
focus on small smoothing angles.

</DOC>
<DOC>
<DOCNO> 101413 </DOCNO>
Higher orbital integrals, Shalika germs, and the Hochschild homology of


  We give a detailed calculation of the Hochschild and cyclic homology of the
algebra $\CIc(G)$ of locally constant, compactly supported functions on a
reductive p-adic group G. We use these calculations to extend to arbitrary
elements the definition the higher orbital integrals introduced in
\cite{Blanc-Brylinski} for regular semisimple elements. Then we extend to
higher orbital integrals some results of Shalika. We also investigate the
effect of the ``induction morphism'' on Hochschild homology.

</DOC>
<DOC>
<DOCNO> 40621 </DOCNO>
B decays to final states including D_s^{(*)} and D^*


  The e^+e^- annihilation data recorded with the BABAR detector has been used
to study B decays to D_s^(*) and D^* mesons. The production fraction of
inclusive D_s^(*) and the corresponding momentum spectra have been determined.
Exclusive decays B^0 --> D^{*-}D_s^{(*)+} have been identified with a partial
reconstruction technique and their branching fractions have been measured. We
also report branching fraction measurements for the exclusive hadronic modes
B^0 --> D^{*-} pi^+ and B^0 --> D^{*-} rho^+.

</DOC>
<DOC>
<DOCNO> 117314 </DOCNO>
Enhancement of bichromatic high-harmonic generation with a


  Using a high-frequency field superposed to a linearly polarized bichromatic
laser field composed by a wave with frequency $\omega $ and a wave with
frequency $2\omega $, we show it is possible to enhance the intensity of a
group of high harmonics in orders of magnitude. These harmonics have
frequencies about 30% higher than the monochromatic-cutoff frequency, and,
within the three-step-model framework, correspond to a set of electron
trajectories for which tunneling ionization is strongly suppressed. Particular
features in the observed enhancement suggest that the high-frequency field
provides an additional mechanism for the electron to reach the continuum. This
interpretation is supported by a time-frequency analysis of the harmonic yield.
The additional high frequency field permits the control of this group of
harmonics leaving all other sets of harmonics practically unchanged, which is
an advantage over schemes involving only bichromatic fields.

</DOC>
<DOC>
<DOCNO> 170529 </DOCNO>
Separability properties of tripartite states with UxUxU-symmetry


  We study separability properties in a 5-dimensional set of states of quantum
systems composed of three subsystems of equal but arbitrary finite Hilbert
space dimension d. These are the states, which can be written as linear
combinations of permutation operators, or, equivalently, commute with unitaries
of the form UxUxU. We compute explicitly the following subsets and their
extreme points: (1) triseparable states, which are convex combinations of
triple tensor products, (2) biseparable states, which are separable for a
twofold partition of the system, and (3) states with positive partial transpose
with respect to such a partition. Tripartite entanglement is investigated in
terms of the relative entropy of tripartite entanglement and of the trace norm.

</DOC>
<DOC>
<DOCNO> 116957 </DOCNO>
Faraday Cup Measurements of Ions Backstreaming into a Electron Beam


  The next generation of radiographic machines based on induction accelerators
is expected to generate multiple, small diameter x-ray spots of high intensity.
Experiments to study the interaction of the electron beam with plasmas
generated at the x-ray converter and at beamline septa are being performed at
the Lawrence Livermore National Laboratory (LLNL) using the 6-MeV, 2-kA
Experimental Test Accelerator (ETA) electron beam. The physics issues of
concern can be separated into two categories. The interaction of subsequent
beam pulses with the expanding plasma plume generated by earlier pulses
striking the x-ray converter or a septum, and the more subtle effect involving
the extraction of light ions from a plasma by the head of the beam pulse. These
light ions may be due to contaminants on the surface of the beam pipe or
converter, or, for subsequent pulses, in the material of the converter. The
space charge depression of the beam could accelerate the light ions to
velocities of several mm/ns. As the ions moved through the body of the incoming
pulse, the beam would be pinched resulting in a moving focus prior to the
converter and a time varying x-ray spot. Studies of the beam-generated plasma
at the x-ray converter have been previously reported. In this paper we describe
Faraday cup measurements performed to detect and quantify the flow of
backstreaming ions as the ETA beam pulse impinges on preformed plasma.
  * This work was performed under the auspices of the U.S. Department of Energy
by University of California Lawrence Livermore National Laboratory under
contract No. W-7405-Eng-48.

</DOC>
<DOC>
<DOCNO> 70819 </DOCNO>
Minimal Model of Dilatonic Gravity and Cosmological Constant


  We consider: minimal scalar-tensor model of gravity with Brans-Dicke factor
$\omega(\Phi)\equiv 0$ and cosmological factor $\Pi(\Phi)$; restrictions on it
from gravitational experiments; qualitative analysis of new approach to
cosmological constant problem based on the huge amount of action in Universe;
determination of $\Pi(\Phi)$ using time evolution of scale factor of Universe.

</DOC>
<DOC>
<DOCNO> 84340 </DOCNO>
A New Study about the Two Formulations of Conservation Laws for Matter


  The debate on conservation laws in general relativity eighty years ago is
reviewed and restudied. The physical meaning of the identities in the
conservation laws for matter plus gravitational field is reexamined and new
interpretations for gravitational wave are given. The conclusions of these
studies are distinct from the prevalent views, it can be demonstrated that
gravitational wave does not transmit energy (and momentum) but only transmits
informations. An experimental test is offered to decide which conservation laws
are correct.

</DOC>
<DOC>
<DOCNO> 83100 </DOCNO>
Materialized View Selection and Maintenance Using Multi-Query


  Because the presence of views enhances query performance, materialized views
are increasingly being supported by commercial database/data warehouse systems.
Whenever the data warehouse is updated, the materialized views must also be
updated. However, whereas the amount of data entering a warehouse, the query
loads, and the need to obtain up-to-date responses are all increasing, the time
window available for making the warehouse up-to-date is shrinking. These trends
necessitate efficient techniques for the maintenance of materialized views.
  In this paper, we show how to find an efficient plan for maintenance of a
{\em set} of views, by exploiting common subexpressions between different view
maintenance expressions. These common subexpressions may be materialized
temporarily during view maintenance. Our algorithms also choose
subexpressions/indices to be materialized permanently (and maintained along
with other materialized views), to speed up view maintenance. While there has
been much work on view maintenance in the past, our novel contributions lie in
exploiting a recently developed framework for multiquery optimization to
efficiently find good view maintenance plans as above. In addition to faster
view maintenance, our algorithms can also be used to efficiently select
materialized views to speed up workloads containing queries.

</DOC>
<DOC>
<DOCNO> 69119 </DOCNO>
The effects of Majorana phases in three-generation neutrinos


  Neutrino-oscillation solutions for the atmospheric neutrino anomaly and the
solar neutrino deficit can determine the texture of the neutrino mass matrix
according to three types of neutrino mass hierarchies as Type A: $m_1^{} \ll
m_2^{} \ll m_3^{}$,
  Type B: $m_1^{} \sim m_2^{} \gg m_3^{}$, and Type C: $m_1^{} \sim m_2^{} \sim
m_3^{}$, where $m_i$ is the $i$-th generation neutrino absolute mass. The
relative sign assignments of neutrino masses in each type of mass hierarchies
play the crucial roles for the stability against quantum corrections. Actually,
two physical Majorana phases in the lepton flavor mixing matrix connect among
the relative sign assignments of neutrino masses. Therefore, in this paper we
analyze the stability of mixing angles against quantum corrections according to
three types of neutrino mass hierarchies (Type A, B, C) and two Majorana
phases. Two phases play the crucial roles for the stability of the mixing
angles against the quantum corrections.

</DOC>
<DOC>
<DOCNO> 170429 </DOCNO>
Quantum phase retrieval of a Rydberg wave packet using a half-cycle


  A terahertz half-cycle pulse was used to retrieve information stored as
quantum phase in an $N$-state Rydberg atom data register. The register was
prepared as a wave packet with one state phase-reversed from the others (the
"marked bit"). A half-cycle pulse then drove a significant portion of the
electron probability into the flipped state via multimode interference.

</DOC>
<DOC>
<DOCNO> 152218 </DOCNO>
Four - Point Functions of Chiral Primary Operators in N=4 SYM


  We discuss recent progress in the determination of correlators of chiral
primary operators in N=4 Super-Yang-Mills theory, based on a combination of
superconformal covariance arguments in N=2 harmonic superspace, and
Intriligator's insertion formula. Applying this technique to the calculation of
the supercurrent four - point function we obtain a compact and explicit result
for its three-loop contribution with comparatively little effort.

</DOC>
<DOC>
<DOCNO> 99411 </DOCNO>
Connections in Poisson Geometry I: Holonomy and Invariants


  We discuss contravariant connections on Poisson manifolds. For vector
bundles, the corresponding operational notion of a contravariant derivative had
been introduced by Izu Vaisman. We show that these connections play an
important role in the study of global properties of Poisson manifolds and we
use them to define Poisson holonomy and new invariants of Poisson manifolds.

</DOC>
<DOC>
<DOCNO> 9822 </DOCNO>
Absence of lattice strain anomalies at the electronic topological


  High pressure structural distortions of the hexagonal close packed (hcp)
element zinc have been a subject of controversy. Earlier experimental results
and theory showed a large anomaly in lattice strain with compression in zinc at
about 10 GPa which was explained theoretically by a change in Fermi surface
topology. Later hydrostatic experiments showed no such anomaly, resulting in a
discrepancy between theory and experiment. We have computed the compression and
lattice strain of hcp zinc over a wide range of compressions using the
linearized augmented plane wave (LAPW) method paying special attention to
k-point convergence. We find that the behavior of the lattice strain is
strongly dependent on k-point sampling, and with large k-point sets the
previously computed anomaly in lattice parameters under compression disappears,
in agreement with recent experiments.

</DOC>
<DOC>
<DOCNO> 80954 </DOCNO>
On the 1-loop lattice perturbation theory of the supersymmetric Ward


  The one loop corrections to the supersymmetric Ward identities (WIs) in the
discretized N=1 SU(2) supersymmetric Yang-Mills theory can be investigated by
means of lattice perturbation theory. The supersymmetry (SUSY) is explicitly
broken by the lattice discretization as well as by the introduction of Wilson
fermions. However, the renormalization of the supercurrent can be carried out
in a scheme that restores the nominal continuum WIs. We present our work in
progress which is concerned with the 1-loop renormalization of the local
supercurrent, i.e. with the perturbative computation of the corresponding
renormalization constants and mixing coefficients.

</DOC>
<DOC>
<DOCNO> 122330 </DOCNO>
Are Radio Pulsars Strange Stars ?


  A remarkably precise observational relation for pulse core component widths
of radio pulsars is used to derive stringent limits on pulsar radii, strongly
indicating that pulsars are strange stars rather than neutron stars. This is
achieved by inclusion of general relativistic effects due to the pulsar mass on
the size of the emission region needed to explain the observed pulse widths,
which constrain the pulsar masses to be less than 2.5 Solar masses and radii to
be smaller than 10.5 km.

</DOC>
<DOC>
<DOCNO> 80866 </DOCNO>
The interaction between center monopoles in SU(2) Yang-Mills


  We study the potential between a static center monopole and antimonopole in
4d SU(2) Yang-Mills theory. Using a new numerical method, we show that the 't
Hooft loop is a dual order parameter with respect to the Wilson loop, for the
deconfinement phase transition. We observe a 3d Ising-like critical behaviour
for the dual string tension related to the spatial 't Hooft loop as a function
of the temperature.

</DOC>
<DOC>
<DOCNO> 122075 </DOCNO>
Clusters of Galaxies in the 2dF Galaxy Redshift Survey


  The 2dF Galaxy Redshift Survey has obtained 135,000 redshifts for galaxies in
two broad strips. Here we present the first results of a 3-dimensional search
for galaxy clusters based on known 2-dimensional compilations. We derive new
redshifts and velocity dispersions for clusters, assess the level of
contamination in the sample, analyze the accuracy of photometric redshift
estimates and study the space distribution of clusters.

</DOC>
<DOC>
<DOCNO> 100226 </DOCNO>
Canonical stability in terms of singularity index for algebraic


  Let X be a projective 3-fold with at most Q-factorial terminal singularities
on which K_X is nef and big. Suppose the canonical index r(X)>1. For any
positive integer m, it is interesting to consider the base point freeness and
birationality of the divisor mK_X. For example, we know the following results:
  (1) the system |5rK_X| is base point free (Ein-Lazarsfeld-Lee);
  (2) |mK_X| gives a birational map for all m>4r+2 (M. Hanamura).
  This article aims to present a better result in direction (2). As far as our
method can tell here, |mK_X| gives a birational map for all m>2r+5. (Q-divisor
method + patient calculation)

</DOC>
<DOC>
<DOCNO> 118542 </DOCNO>
High resolution near-infrared polarimetry of Eta Carinae and the


  High resolution near-infrared adaptive optics imaging and polarimetry have
been obtained of the Homunculus Nebula and its central star Eta Carinae (HD
93308). Maps of the linear polarization at a resolution of <0.2'' have been
made in the J, H and K bands and in a narrow 2.15micron continuum band (K_c).
The overall appearance of the nebula in the near-IR is similar in all bands and
to that at V, with specific features less sharp to longer wavelengths. The
large-scale pattern of polarization vectors is centro-symmetric demonstrating
that single scattering dominates everywhere except perhaps in the central
bright core. Polarization maps at K_c in the near vicinity of Eta Carinae were
restored using a PSF derived from blind deconvolution. An extension of the flux
in the direction of the optically visible speckle knots was detected, with 18%
polarization determined for one knot.
  The most remarkable result of the linear polarization mapping is the level of
similarity in the spatial structure, and the degree of polarization, between
the near-IR and optical data. Such a polarization pattern cannot arise in Mie
scattering from a single power law distribution of grain sizes unless the
particles are very small compared with the wavelength, in disagreement with
mid-IR observations. The colour dependence of the extinction was found to be
shallower than the typical ISM, indicating the presence of large grains.
Optical depth effects and a broad distribution in grain sizes are suggested to
explain these contradictory results, perhaps with a dependence of the grain
size with depth into the small obscuring clouds in the Homunculus lobes.
However the presence of aligned grains, previously inferred from mid-IR
polarization, may also affect the dust-scattered radiation. (Abridged abstract)

</DOC>
<DOC>
<DOCNO> 119595 </DOCNO>
An excess of submm sources near 4C41.17: a candidate proto-cluster at


  Biased galaxy-formation theories predict that massive galaxies at high
redshifts should act as signposts to high-density environments in the early
Universe, which subsequently evolve into the cores of the richest clusters seen
at the present day. These regions are characterised by over-densities of young
galaxies, perhaps including a population of dusty, interaction-driven
starbursts - the progenitors of massive cluster ellipticals. By searching for
this population at submm wavelengths we can therefore test both galaxy- and
structure-formation models. We have undertaken such a search in the field of a
z=3.8 radio galaxy, 4C41.17, with the SCUBA submm camera. Our extremely deep
450- and 850-micron maps reveal an order-of-magnitude over-density of luminous
submm galaxies compared to typical fields (the likelihood of finding such an
over-density in a random field is <2E-3). The SCUBA galaxies have bolometric
luminosities, >10^13 L(solar), which imply star-formation rates consistent with
those required to form a massive galaxy in only a few 10^8 years. We also note
that this field exhibits an over-density of extremely red objects (EROs), some
of which may be associated with the submm sources, and Lyman-break galaxies. We
propose that the over-densities of both submm and ERO sources in this field
represent young dusty, starburst galaxies forming within a proto-cluster
centered on the radio galaxy at z=3.8, which is also traced by a less-obscured
population of Lyman-break galaxies.

</DOC>
<DOC>
<DOCNO> 102314 </DOCNO>
Dehn fillings creating essential spheres and tori


  Let $M$ be a simple 3-manifold with a toral boundary component. It is known
that if two Dehn fillings on $M$ along the boundary produce a reducible
manifold and a toroidal manifold, then the distance between the filling slopes
is at most three. This paper gives a remarkably short proof of this result.

</DOC>
<DOC>
<DOCNO> 116309 </DOCNO>
The Multifractal Time and Irreversibility in Dynamic Systems


  The irreversibility of the equations of classical dynamics (the Hamilton
equations and the Liouville equation) in the space with multifractal time is
demonstrated. The time is given on multifractal sets with fractional
dimensions. The last depends on densities of Lagrangians in a given time moment
and in a given point of space. After transition to sets of time points with the
integer dimension the obtained equations transfer in the known equations of
classical dynamics. Production of an entropy is not equally to zero in space
with multifractal time, i.e. the classical systems in this space are
non-closed.

</DOC>
<DOC>
<DOCNO> 99550 </DOCNO>
Contact cuts


  We describe a contact analog of the symplectic cut construction. As an
application we show that the group of contactomorphisms for a particular
overtwisted contact structure on the three sphere contains countably many
nonconjugate two tori.

</DOC>
<DOC>
<DOCNO> 101462 </DOCNO>
On Quasidiagonal C*-algebras


  We give a detailed survey of the theory of quasidiagonal C*-algebras. The
main structural results are presented and various functorial questions around
quasidiagonality are discussed. In particular we look at what is currently
known (and not known) about extensions, quotients, tensor products, ect. of
quasidiagonal C*-algebras. We also point out how quasidiagonality is connected
to some important open problems.

</DOC>
<DOC>
<DOCNO> 150733 </DOCNO>
The Central Charge in 3D Simple Superalgebra


  A matter self-interacting model with N=1-supersymmetry in 3D is discussed in
connection with the appearance of a central charge in the algebra of the
supersymmetry generators. The result is extended to include gauge fields with a
Chern-Simons term. The main result is that, for a simple supersymmetry, only
the matter sector contributes to the central charge in contrast to what occurs
in the N=2 case.

</DOC>
<DOC>
<DOCNO> 170316 </DOCNO>
Private entanglement over arbitrary distances, even using noisy


  We give a security proof of quantum cryptography based entirely on
entanglement purification. Our proof applies to all possible attacks
(individual and coherent). It implies the security of cryptographic keys
distributed with the help of entanglement-based quantum repeaters. We prove the
security of the obtained quantum channel which may not only be used for quantum
key distribution, but also for secure, albeit noisy, transmission of quantum
information.

</DOC>
<DOC>
<DOCNO> 116910 </DOCNO>
Coherent Synchrotron Radiation Measurements in the CLIC Test Facility


  Bunches of high charge (up to 10 nC) are compressed in length in the CTF II
magnetic chicane to less than 0.2 mm rms. The short bunches radiate coherently
in the chicane magnetic field, and the horizontal and longitudinal phase space
density distributions are affected. This paper reports the results of beam
emittance and momentum measurements. Horizontal and vertical emittances and
momentum spectra were measured for different bunch compression factors and
bunch charges. In particular, for 10 nC bunches, the mean beam momentum
decreased by about 5% while the FWHM momentum spread increased from 5% to 19%.
The experimental results are compared with simulations made with the code
TraFiC4.

</DOC>
<DOC>
<DOCNO> 116319 </DOCNO>
Dynamics of Atom-Mediated Photon-Photon Scattering I: Theory


  The mediated photon-photon interaction due to the resonant Kerr nonlinearity
in an inhomogeneously broadened atomic vapor is considered. The time-scale for
photon-photon scattering is computed and found to be determined by the
inhomogeneous broadening and the magnitude of the momentum transfer. This time
can be shorter than the atomic relaxation time. Effects of atom statistics are
included and the special case of small-angle scattering is considered. In the
latter case the time-scale of the nonlinear response remains fast, even though
the linear response slows as the inverse of the momentum transfer.

</DOC>
<DOC>
<DOCNO> 71991 </DOCNO>
Gravitino production during preheating and the equivalence theorem


  We review our results on the calculation of helicity 1/2 gravitino production
during preheating. The method we present is based on the equivalence between
goldstinos and longitudinal gravitinos at high energies. The problem is thus
reduced to the standard (Majorana) fermion production after inflation.
Comparison between helicity 3/2 and 1/2 production and with the results
obtained in the unitary gauge is also presented.

</DOC>
<DOC>
<DOCNO> 99386 </DOCNO>
Lefschetz numbers of iterates of the monodromy and truncated arcs


  We express the Lefschetz number of iterates of the monodromy of a function on
a smooth complex algebraic variety in terms of the Euler characteristic of a
space of truncated arcs.

</DOC>
<DOC>
<DOCNO> 119390 </DOCNO>
VLA Imaging of the Disk Surrounding the Nearby Young Star TW Hya


  The TW Hya system is perhaps the closest analog to the early solar nebula. We
have used the Very Large Array to image TW Hya at wavelengths of 7mm and 3.6 cm
with resolutions 0.1 arcseconds (about 5 AU) and 1.0 arcseconds (about 50 AU),
respectively. The 7mm emission is extended and appears dominated by a dusty
disk of radius larger than 50 AU surrounding the star. The 3.6 cm emission is
unresolved and likely arises from an ionized wind or gyrosynchrotron activity.
The dust spectrum and spatially resolved 7mm images of the TW Hya disk are
fitted by a simple model with temperature and surface density described by
radial power laws, $T(r)\propto r^{-0.5}$ and $\Sigma(r) \propto r^{-1}$. These
properties are consistent with an irradiated gaseous accretion disk of mass
$\sim0.03~{\rm M_{\odot}}$ with an accretion rate $\sim10^{-8}~{\rm
M_{\odot}yr^{-1}}$ and viscosity parameter $\alpha = 0.01$. The estimates of
mass and mass accretion rates are uncertain as the gas-to-dust ratio in the TW
Hya disk may have evolved from the standard interstellar value.

</DOC>
<DOC>
<DOCNO> 70859 </DOCNO>
Top quark production near threshold at NLC


  In this talk we discuss the process e+e- -> t t-bar near threshold. In
particular we discuss a quark mass definition which is a generalization of the
static PS mass. The new definition allows us to calculate recoil corrections to
the static PS mass. Using this result we calculate the cross section of e+e- ->
t t-bar near threshold at NNLO accuracy adopting three alternative approaches,
namely (1) fixing the pole mass, (2) fixing the PS mass, and (3) fixing the new
mass which we call the PS-bar mass. We demonstrate that perturbative
predictions for the cross section become much more stable if we use the PS or
the PS-bar mass for the calculations. A careful analysis suggests that the top
quark mass can be extracted from a threshold scan at NLC with an accuracy of
about 100-200 MeV.

</DOC>
<DOC>
<DOCNO> 13798 </DOCNO>
Spin tunnelling in Molecular Magnets


  We study spin tunneling in magnetic molecules, with special reference to Fe8.
The article aims to give a pedagogical discussion of what is meant by the
tunneling of a spin, and how tunneling amplitudes or energy level splittings
may be calculated using path integral and discrete phase integral methods. In
the case of Fe8, an issue of great interest is the oscillatory tunnel
splittings as a function of applied magnetic field that have recently been
observed. These oscillations are due to the occurrence of diabolical points in
the magnetic field space. It is shown how this effect comes about in both the
path-integral and the discrete phase integral methods. In the former it arises
due to the presence of a Berry-like phase in the action, which gives rise to an
interference between tunneling trajectories. In the latter, it arises due to
the presence of further neighbor terms in the recursion relation for the energy
eigenfunction. These terms give rise to turning points which have no analog in
the one-dimensional continuum quasiclassical method. Explicit results are
obtained for the location of the diabolical points in Fe8.

</DOC>
<DOC>
<DOCNO> 101609 </DOCNO>
Families of four dimensional manifolds that become mutually


  In this paper, we will introduce a cut and paste move, called a geometrically
null log transform, and prove that any two manifolds related by a sequence of
these moves become diffeomorphic afte r one stabilization. To motivate the cut
and paste move, we will use the symplec tic fiber sum, and a construction of
Fintushel and Stern to construct several large families of 4-manifolds. We will
then proceed to prove that the members of any one of these families become
diffeomorphic after one stabilization. Finally, we will compute the
Seiberg-Witten invariants of each member of each of the families.

</DOC>
<DOC>
<DOCNO> 178645 </DOCNO>
Photonuclear Reactions of Three-Nucleon Systems


  We discuss the available data for the differential and the total cross
section for the photodisintegration of $^3$He and $^3$H and the corresponding
inverse reactions below $E_\gamma = 100$ MeV by comparing with our calculations
using realistic $NN$ interactions. The theoretical results agree within the
errorbars with the data for the total cross sections. Excellent agreement is
achieved for the angular distribution in case of $^3$He, whereas for $^3$H a
discrepancy between theory and experiment is found.

</DOC>
<DOC>
<DOCNO> 117818 </DOCNO>
Dynamics of Warm-Absorbing Gas in Seyfert Galaxies: NGC 5548


  A hydromagnetic (MHD) wind from a clumpy molecular accretion disk is invoked
to explain observations of warm absorbing (WA) gas in UVX from Sy galaxies.
This paper focuses on two issues: (1) compatibility of kinematics and dynamics
of MHD wind with the observed properties of WAs; and (2) relationship between
the UVX absorptions. We provide an in-depth comparison between the MHD model
and the Sy 1 galaxy NGC 5548, which at high spectral resolution exhibits a
number of discrete UV absorption components. We find that: (1) the total column
densities of Ovii, Oviii and H, are reproduced by constraining the UV ion
column densities of Civ and Nv in each component to lie within a factor of 2 of
their observed values and optimizing over the possible sets of component
ionization states and Civ column densities; (2) the WA exists in the outer part
of the wind and is not a continuation of the flow in the BLR; and (3) the WA
extends in radial and polar directions and is ionization-stratified. X-ray
absorption is found to be heavily biased towards smaller r, and UV absorption
originates at larger distances from the central continuum source. We show that
the discrete absorption components along the line-of-sight are intrinsically
clumpy. Density differences between kinematic components result in a range of
ionization and recombination timescales. We further test the applicability of
the MHD wind to WAs in general, by constructing a quasi-continuous flow model,
and extending it to arbitrary aspect angles. We estimate the fraction of Sy 1s
having detectable WAs with larger Ovii column density than Oviii, and the range
of total H column densities. We also find that the ratio of Ovii to Oviii
optical depths can serve as a new diagnostic of AGN aspect angle.

</DOC>
<DOC>
<DOCNO> 40327 </DOCNO>
Study of the CP asymmetry of B0 -> J/psi K0S decays in ALEPH


  The decay B0 -> J/psi K0_S is reconstructed with J/psi -> e+ e- or mu+ mu-
and K0_S -> pi+ pi-. From the full ALEPH dataset at LEP1 of about 4 million
hadronic Z decays, 23 candidates are selected with an estimated purity of 71%.
They are used to measure the CP asymmetry of this decay, given by sin 2beta in
the Standard Model, with the result sin 2beta = 0.84 +0.82-1.04 +-0.16. This is
combined with existing measurements from other experiments, and increases the
confidence level that CP violation has been observed in this channel to 98%.

</DOC>
<DOC>
<DOCNO> 12002 </DOCNO>
A Comment on the Tsallis Maximum Entropy Principle


  Tsallis has suggested a nonextensive generalization of the Boltzmann-Gibbs
entropy, the maximization of which gives a generalized canonical distribution
under special constraints. In this brief report we show that the generalized
canonical distribution so obtained may differ from that predicted by the law of
large numbers when empirical samples are held to the same constraint. This
conclusion is based on a result regarding the large deviation property of
conditional measures and is confirmed by numerical evidence.

</DOC>
<DOC>
<DOCNO> 121731 </DOCNO>
Comparison of Parallaxes from Eclipsing Binaries Method with Hipparcos


  The parallaxes determined by Lacy (1979) by means of eclipsing binaries
method are compared with the Hipparcos parallaxes for 19 systems. The residual
scatter of the distance moduli inferred from eclipsing binaries method - after
allowing for known errors as given by Lacy and Hipparcos - is equal to 0.18
mag. It decreases to 0.08 mag when obviously not fitting semi-detached systems
and systems with chromospheric activity of components are removed from the
sample.

</DOC>
<DOC>
<DOCNO> 39799 </DOCNO>
Golden measurements at a neutrino factory


  The precision and discovery potential of a neutrino factory based on muon
storage rings is studied. For three-family neutrino oscillations, we analyse
how to measure or severely constraint the angle $\theta_{13}$, CP violation,
MSW effects and the sign of the atmospheric mass difference $\Delta m^2_{23}$.
We present a simple analytical formula for the oscillation probabilities in
matter, with all neutrino mass differences non-vanishing, which clarifies the
subtleties involved in disentangling the unknown parameters. The appearance of
``wrong-sign muons'' at three reference baselines is considered: 732 km, 3500
km, and 7332 km. We exploit the dependence of the signal on the neutrino
energy, and include as well realistic background estimations and detection
efficiencies. The optimal baseline turns out to be ${\cal O}(3000$ km).
Analyses combining the information from different baselines are also presented.

</DOC>
<DOC>
<DOCNO> 40156 </DOCNO>
Study of ATLAS Sensitivity to FCNC TOP Quark Decay t--> Zq


  The sensitivity of ATLAS experiment to the top-quark rare decay via flavor-
changing neutral currents t \to Zq (q represents c and u quarks) have been
studied at \sqrt{s}= 14 TeV in two decay modes:
  1. The pure leptonic decay of gauge bosons: t\bar{t} \to ZqWb \to l^{+} l^{-}
j l^{+-} nu j_{b} (l=e, mu)
  2. The leptonic decay of Z bosons and hadronic decay of W bosons t\bar{t} \to
ZqWb \to l^{+} l^{-} jjjj_{b} (l=e, mu)
  The dominant backgrounds Z-jets, Zw and t\bar{t} has been analysed. The
signal and backgrounds were generated via PYTHIA 5.7, simulated and analysed
using ATLFAST 2.14. A branching ratio for t \to Zq as low as 1.1x1-^{4} for the
leptonic mode and 2.3x10^{4} for hadronic mode could be discovered at the
5\sigma level with an integrated luminosity of 10^{5} pb^{-1}.

</DOC>
<DOC>
<DOCNO> 8045 </DOCNO>
Composite Fermions in Fractional Quantum Hall Systems


  The composite Fermion (CF) picture offers a simple intuitive way of
understanding many of the surprising properties of a strongly interacting
two-dimensional electron fluid in a large magnetic field. The simple way in
which the mean field CF picture describes the low lying bands of angular
momentum multiplets for any value of the applied magnetic field is illustrated
and compared with the results of exact numerical diagonalization of small
systems. The justification of the success of the CF approach is discussed in
some detail, and a CF hierarchy picture of the incompressible quantum fluid
states is introduced. The CF picture is used to understand the energy spectrum
and photoluminescence of systems containing both electrons and valence band
holes.

</DOC>
<DOC>
<DOCNO> 150574 </DOCNO>
Absorption by Extremal D3-branes


  The absorption in the extremal D3-brane background is studied for a class of
massless fields whose linear perturbations leave the ten-dimensional background
metric unperturbed, as well as the minimally-coupled massive scalar. We find
that various fields have the same absorption probability as that of the
dilaton-axion system, which is given exactly via the Mathieu equation. We
analyze the features of the absorption cross-sections in terms of effective
Schr\"odinger potentials, conjecture a general form of the dual effective
potentials, and provide explicit numerical results for the whole energy range.
As expected, all partial-wave absorption probabilities tend to zero (one) at
low (large) energies, and exhibit an oscillatory pattern as a function of
energy. The equivalence of absorption probabilities for various modes has
implications for the correlation functions on the field, including subleading
contributions on the field-theory side. In particular, certain half-integer and
integer spin fields have identical absorption probabilities, thus providing
evidence that the corresponding operator pairs on the field theory side belong
to the same supermultiplets.

</DOC>
<DOC>
<DOCNO> 72320 </DOCNO>
Meissner effect for color superconducting quark matter


  The behaviour of the magnetic field inside the superconducting quark matter
core of a neutron star is investigated in the framework of the Ginzburg-Landau
theory. We take into account the simultaneous coupling of the diquark
condensate field to the usual magnetic and to the gluomagnetic gauge fields. We
solve the problem for three different physical situations: a semi-infinite
region with a planar boundary, a spherical region, and a cylindrical region. We
show that Meissner currents near the quark core boundary effectively screen the
external static magnetic field.

</DOC>
<DOC>
<DOCNO> 39969 </DOCNO>
Charmonium absorption by nucleons


  $J/\Psi$ dissociation in collisions with nucleons is studied within a boson
exchange model and the energy dependence of the dissociation cross section is
calculated from the threshold for $\Lambda_c{\bar D}$ production to high
energies. We illustrate the agreement of our results with calculations based on
short distance QCD and Regge theory. The compatibility between our calculations
and the data on $J/\Psi$ photoproduction on a nucleon is discussed. We evaluate
the elastic $J/\Psi{+}N$ cross section using a forward dispersion relation and
demonstrate the overall agreement with the predictions from QCD sum rules. Our
results are compatible with the phenomenological dissociation cross section
evaluated from the experimental data on $J/\Psi$ production from $\gamma{+}A$,
$p{+}A$ and $A{+}A$ collisions.

</DOC>
<DOC>
<DOCNO> 117617 </DOCNO>
Implications of Abundance Gradients in Intracluster Gas


  Analysis of spatially resolved ASCA spectra of the intracluster gas in Abell
496 confirms that metal abundances increase toward the center. We also find
spatial gradients in several abundance ratios, indicating that the fraction of
iron from SN Ia increases toward the cluster center. The dominant metal
enrichment mechanism near the cluster center must therefore be different than
in the outer parts. We show that ram pressure stripping of gas from cluster
galaxies cannot account for the central abundance enhancement. We suggest that
two successive stages of galactic winds contaminate intracluster gas:
protogalactic winds driven by SN II, followed by less energetic winds driven by
SN Ia, which have longer lived progenitors than SN II. The less energetic
secondary wind from a cD galaxy may be suppressed, due to its location at the
cluster center, leading to the observed central enhancement of SN Ia ejecta.

</DOC>
<DOC>
<DOCNO> 101641 </DOCNO>
Variational representations of Varadhan Functionals


  Motivated by the theory of large deviations, we introduce a class of
non-negative non-linear functionals that have a variational "rate function"
representation.

</DOC>
<DOC>
<DOCNO> 122802 </DOCNO>
The Accretion-Ejection Instability and a "Magnetic Flood" scenario for


  I present a global view of recent results on the Accretion-Ejection
Instability (AEI), described in more details in other contributions to this
workshop. These results address essentially the characteristics of the AEI as a
good candidate to explain the low-frequency QPO of X-ray binaries, in
particular (at $\sim 1-10$ Hz) of micro-quasars. I then discuss how, if the AEI
is considered as the source of the QPO, a possible scenario can be considered
where the $\sim 30$ mn. cycles of GRS 1915+105 are controlled by the evolution
of magnetic flux in the disk.

</DOC>
<DOC>
<DOCNO> 116886 </DOCNO>
Spectroscopic investigations of a dielectric-surface-discharge plasma


  Spectroscopic investigations of the properties of a plasma produced by a
flashboard plasma source, commonly used in pulsed plasma experiments, are
presented. The plasma is used to prefill a planar 0.4-ms-conduction time plasma
opening switch (POS). A novel gas-doping technique and a secondary surface
flashover plasma source are used to locally dope the plasma with gaseous and
solid materials, respectively, allowing for spatially-resolved measurements.
The electron density, temperature, and plasma composition are determined from
spectral line intensities and line profiles. Detailed collisional-radiative
modeling is used to analyze the observed line intensities. The propagation
velocity and divergence angle of various ions are determined from
time-of-flight measurements and Doppler broadening of spectral lines,
respectively. This allows for distinguishing the secondary plasma ejected from
the POS electrodes from the plasma of the flashboard source.

</DOC>
<DOC>
<DOCNO> 70423 </DOCNO>
Color Dipole Systematics of the Diffraction Slope in Diffractive Photo-


  We present the first evaluation of the color dipole diffraction slope from
the data on diffractive photo- and electroproduction of vector mesons. The
energy and dipole size dependence of the found dipole diffraction slope are
consistent with the color dipole gBFKL dynamics.

</DOC>
<DOC>
<DOCNO> 116428 </DOCNO>
Hierarchic Theory of Complex Systems (biosystems, colloids):


  1. Protein domain mesoscopic organization 2. Quantum background of lipid
domain organization in biomembranes 3. Hierarchic approach to theory of
solutions and colloid systems 4. Distant solvent-mediated interaction between
macromolecules 5. Spatial self-organization in the water-macromolecular systems
6. Properties of [bisolvent - polymer system] 7. Osmosis and solvent activity.
Traditional and mesoscopic approach

</DOC>
<DOC>
<DOCNO> 122883 </DOCNO>
Mass profiles and anisotropies of early-type galaxies


  We discuss the problem of using stellar kinematics of early-type galaxies to
constrain the galaxies' orbital anisotropies and radial mass profiles. We
demonstrate that compressing a galaxy's light distribution along the line of
sight produces approximately the same signature in the line-of-sight velocity
profiles as radial anisotropy. In particular, fitting spherically symmetric
dynamical models to apparently round, isotropic face-on flattened galaxies
leads to a spurious bias towards radial orbits in the models, especially if the
galaxy has a weak face-on stellar disk. Such face-on stellar disks could
plausibly be the cause of the radial anisotropy found in spherical models of
intermediate luminosity ellipticals such as NGC 2434, NGC 3379 and NGC 6703.
  In the light of this result, we use simple dynamical models to constrain the
outer mass profiles of a sample of 18 round, early-type galaxies. The galaxies
follow a Tully-Fisher relation parallel to that for spiral galaxies, but
fainter by at least 0.8 mag (I-band) for a given mass. The most luminous
galaxies show clear evidence for the presence of a massive dark halo, but the
case for dark haloes in fainter galaxies is more ambiguous. We discuss the
observations that would be required to resolve this ambiguity.

</DOC>
<DOC>
<DOCNO> 117143 </DOCNO>
Nonlinear $\delta f$ Method for Beam-Beam Simulation


  We have developed an efficacious algorithm for simulation of the beam-beam
interaction in synchrotron colliders based on the nonlinear $\delta f$ method,
where $\delta f$ is the much smaller deviation of the beam distribution from
the slowly evolving main distribution $f_0$. In the presence of damping and
quantum fluctuations of synchrotron radiation it has been shown that the slowly
evolving part of the distribution function satisfies a Fokker-Planck equation.
Its solution has been obtained in terms of a beam envelope function and an
amplitude of the distribution, which satisfy a coupled system of ordinary
differential equations. A numerical algorithm suited for direct code
implementation of the evolving distributions for both $\delta f$ and $f_0$ has
been developed. Explicit expressions for the dynamical weights of
macro-particles for $\delta f$ as well as an expression for the slowly changing
$f_0$ have been obtained.

</DOC>
<DOC>
<DOCNO> 10775 </DOCNO>
Interlayer tunneling in double-layer quantum Hall pseudo-ferromagnets


  We show that the interlayer tunneling I--V in double-layer quantum Hall
states displays a rich behavior which depends on the relative magnitude of
sample size, voltage length scale, current screening, disorder and thermal
lengths. For weak tunneling, we predict a negative differential conductance of
a power-law shape crossing over to a sharp zero-bias peak. An in-plane magnetic
field splits this zero-bias peak, leading instead to a ``derivative'' feature
at $V_B(B_{||})=2\pi\hbar v B_{||}d/e\phi_0$, which gives a direct measure of
the dispersion of the Goldstone mode corresponding to the spontaneous symmetry
breaking of the double-layer Hall state.

</DOC>
<DOC>
<DOCNO> 174440 </DOCNO>
Measurement of Tensor Polarization in Elastic Electron-Deuteron


  Tensor polarization observables (t20, t21 and t22) have been measured in
elastic electron-deuteron scattering for six values of momentum transfer
between 0.66 and 1.7 (GeV/c)^2. The experiment was performed at the Jefferson
Laboratory in Hall C using the electron HMS Spectrometer, a specially designed
deuteron magnetic channel and the recoil deuteron polarimeter POLDER. The new
data determine to much larger Q^2 the deuteron charge form factors G_C and G_Q.
They are in good agreement with relativistic calculations and disagree with
pQCD predictions.

</DOC>
<DOC>
<DOCNO> 10324 </DOCNO>
A Numerical Study of Capillary and Viscous Drainage in Porous Media


  This paper reviews recent research results in two-phase flow in porous media
obtained by the authors.

</DOC>
<DOC>
<DOCNO> 151485 </DOCNO>
Which action for brane worlds?


  In his pioneering work on singular shells in general relativity, Lanczos had
derived jump conditions across energy-momentum carrying hypersurfaces from the
Einstein equation with codimension 1 sources. However, on the level of the
action, the discontinuity of the connection arising from a codimension 1
energy-momentum source requires to take into account two adjacent space-time
regions separated by the hypersurface.
  The purpose of the present note is to draw attention to the fact that
Lanczos' jump conditions can be derived from an Einstein action but not from an
Einstein-Hilbert action.

</DOC>
<DOC>
<DOCNO> 170068 </DOCNO>
On quantum logic operations based on photon-exchange interactions in an


  The recently proposed idea to generate entanglement between photon states via
exchange interactions in an ensemble of atoms (J.D. Franson and T.B. Pitman,
Phys. Rev. A 60, 917 (1999) and J.D. Franson et al., (quant-ph/9912121)) is
discussed using an S-matix approach. It is shown that if the nonlinear response
of the atoms is negligible and no additional atom-atom interactions are
present, exchange interactions cannot produce entanglement between photons
states in a process that returns the atoms to their initial state. Entanglement
generation requires the presence of a nonlinear atomic response or atom-atom
interactions.

</DOC>
<DOC>
<DOCNO> 11728 </DOCNO>
Vortex Lines or Vortex-Line Chains at the Lower Critical Field in


  The vortex state at the lower critical field, H_{c1}, in clean anisotropic
superconductors placed in an external field tilted with respect to the axis of
anisotropy (c-axis) is considered assuming two possible arrangements: dilute
vortex-lines or dilute vortex-line chains. By minimizing the Gibbs free
energies in the London limit for each possibility we obtain the corresponding
lower critical fields as a function of the tilt angle. The equilibrium
configuration at H_{c1} for a given tilt angle is identified with that for
which H_{c1} is the smallest. We report results for parameter values typical of
strong and moderate anisotropy. We find that for strong anisotropy vortex-line
chains are favored for small tilt angles (< 7.9^o) and that at 7.9^o there is
coexistence between this configuration and a vortex-line one. For moderate
anisotropy we find that there is little difference between the vortex-line and
the vortex-chain lower critical fields.

</DOC>
<DOC>
<DOCNO> 118333 </DOCNO>
Calibrating Array Detectors


  The development of sensitive large format imaging arrays for the infrared
promises to provide revolutionary capabilities for space astronomy. For
example, the Infrared Array Camera (IRAC) on SIRTF will use four 256 x 256
arrays to provide background limited high spatial resolution images of the sky
in the 3 to 8 micron spectral region. In order to reach the performance limits
possible with this generation of sensitive detectors, calibration procedures
must be developed so that uncertainties in detector calibration will always be
dominated by photon statistics from the dark sky as a major system noise
source. In the near infrared, where the faint extragalactic sky is observed
through the scattered and reemitted zodiacal light from our solar system,
calibration is particularly important. Faint sources must be detected on this
brighter local foreground.
 We present a procedure for calibrating imaging systems and analyzing such
data. In our approach, by proper choice of observing strategy, information
about detector parameters is encoded in the sky measurements. Proper analysis
allows us to simultaneously solve for sky brightness and detector parameters,
and provides accurate formal error estimates.
 This approach allows us to extract the calibration from the observations
themselves; little or no additional information is necessary to allow full
interpretation of the data. Further, this approach allows refinement and
verification of detector parameters during the mission, and thus does not
depend on a priori knowledge of the system or ground calibration for
interpretation of images.

</DOC>
<DOC>
<DOCNO> 120539 </DOCNO>
Mapping the substructure in the Galactic halo with the next generation


  We run numerical simulations of the disruption of satellite galaxies in a
Galactic potential to build up the entire stellar halo, in order to investigate
what the next generation of astrometric satellites will reveal by observing the
halo of the Milky Way. We generate artificial DIVA, FAME and GAIA halo
catalogues, in which we look for the signatures left by the accreted
satellites. We develop a method based on the standard Friends-of-Friends
algorithm applied to the space of integrals of motion. We find this simple
method can recover about 50% of the different accretion events, when the
observational uncertainties expected for GAIA are taken into account, even when
the exact form of the Galactic potential is unknown. The recovery rate for DIVA
and FAME is much smaller, but these missions, like GAIA, should be able to test
the hierarchical formation paradigm on our Galaxy by measuring the amount of
halo substructure in the form of nearby kinematically cold streams with for
example, a two-point correlation function in velocity space.

</DOC>
<DOC>
<DOCNO> 71430 </DOCNO>
QCD analysis of the diffractive structure function F_2^{D(3)}


  The proton diffractive structure function $F_2^{D(3)}$ measured in the H1 and
ZEUS experiments at HERA is analyzed in terms of both Regge phenomenology and
perturbative QCD evolution. A new method determines the values of the Regge
intercepts in ``hard'' diffraction, confirming a higher value of the Pomeron
intercept than for soft physics. The data are well described by a QCD analysis
in which point-like parton distributions, evolving according to the DGLAP
equations, are assigned to the leading and sub-leading Regge exchanges. The
gluon distributions are found to be quite different for H1 and ZEUS. A {\it
global fit} analysis, where a higher twist component is taken from models,
allows us to use data in the whole available range in diffractive mass and
gives a stable answer for the leading twist contribution. We give sets of quark
and gluon parton distributions for the Pomeron, and predictions for the charm
and the longitudinal proton diffractive structure function from the QCD fit. An
extrapolation to the Tevatron range is compared with CDF data on single
diffraction. Conclusions on factorization breaking depend critically whether H1
(strong violation) or ZEUS (compatibility at low $\beta$) fits are taken into
account.

</DOC>
<DOC>
<DOCNO> 117987 </DOCNO>
The HI shell G132.6-0.7-25.3: A Supernova Remnant or an Old Wind-Blown


  Data from the Canadian Galactic Plane Survey reveal an abundance of HI shells
and arcs in the disk of our galaxy. While their shape is suggestive of stellar
winds or supernovae influence, very few of these structures have been examined
in detail thus far. A fine example is an HI shell in the outer Galaxy with no
continuum counterpart discovered in the survey's pilot project. Its size and
kinematics suggest that it was created by the winds of a single late-type O
star which has since evolved off the main sequence or by a supernova explosion.
A B1 Ia star at the centre of the shell, in projection, is a possible candidate
for energy source if the shell is assumed to be wind-blown. The shell's shape
implies a surprisingly small scale height of less than about 30 pc for the
surrounding gas if the elongation is due to evolution in a density gradient.

</DOC>
<DOC>
<DOCNO> 151611 </DOCNO>
Constructions of Non Commutative Instantons on $T^4$ and $K_3$


  We generalize the spectral-curve construction of moduli spaces of instantons
on $\MT{4}$ and $K_3$ to noncommutative geometry. We argue that the
spectral-curves should be constructed inside a twisted $\MT{4}$ or $K_3$ that
is an elliptic fibration without a section. We demonstrate this explicitly for
$T^4$ and to first order in the noncommutativity, for $K_3$. Physically, moduli
spaces of noncommutative instantons appear as moduli spaces of theories with
$\SUSY{4}$ supersymmetry in 2+1D. The spectral curves are related to
Seiberg-Witten curves of theories with $\SUSY{2}$ in 3+1D. In particular, we
argue that the moduli space of instantons of $U(q)$ Yang-Mills theories on a
noncommutative $K_3$ is equivalent to the Coulomb branch of certain 2+1D
theories with ${\cal N} = 4$ supersymmetry. The theories are obtained by
compactifying the heterotic little-string theory on $T^3$ with global twists.
This extends a previous result for noncommutative instantons on $\MT{4}$. We
also briefly discuss the instanton equation on generic curved spaces.

</DOC>
<DOC>
<DOCNO> 121287 </DOCNO>
Probing Cosmology with the X-ray Forest


  There is a growing consensus that in the present universe most baryons reside
in galaxy clusters and groups in the form of highly ionized gas at temperatures
of 10^6 ~ 10^8 K. The H-like and He-like ions of the heavy elements can produce
absorption features - the so-called ``X-ray Forest'' - in the X-ray spectrum of
a background quasar. We investigate the distribution of the X-ray absorption
lines produced by this gas under three different cosmological models: the
standard CDM with Omega_0=1, a flat model with Omega_0=0.3 and an open model
with with Omega_0=0.3. We give a semi- analytic calculation of the X-ray forest
distribution based on the Press- Schechter formalism, following Perna & Loeb
(1998). We choose three ions (O VIII, Si XIV and Fe XXV) and calculate the
distribution functions, the number of absorbers along the LOS to a distant
quasar vs. redshift and column density in a given ion. We find that significant
differences in the evolution of the distribution functions among the three
cosmological models. Using Monte Carlo simulations, we simulate the
distribution of X-ray absorption lines for 10,000 random LOS. We find there are
at least several O VIII lines with column density higher than 10^16 cm^-2.
Finally we explore the possibility of detecting the X-ray forest with current
and upcoming X-ray missions and we present an XMM RGS simulation of a
representative quasar X-ray spectrum.

</DOC>
<DOC>
<DOCNO> 119705 </DOCNO>
Orbital Motion of Resonant Clumps in Dusty Circumstellar Disks as a


  We have applied a powerful numerical approach to compute, with a high
resolution, the structure of dusty circumstellar disks with embedded planets.
We emphasize some testable implications of our simulations which would verify
the presence of a planet via thermal emission of one or more dusty clumps which
are in mean motion resonances with the planet. In particular, our simulations
indicate that Vega may have a massive planet of m~2 m_J (m_J being Jupiter's
mass) at a distance of 50-60 AU, and Epsilon Eri may have a less massive planet
of m~0.2 m_J at a similar distance of 55-65 AU. This conclusion is testable:
Each resonant feature is stationary in the reference frame co-rotating with the
planet, but it is not so for the observer at Earth. Therefore, if our
interpretation of asymmetric clumps in circumstellar disks as dynamical
resonant structures is correct, the above pattern revolves around the star with
an angular velocity of (1.2-1.6) deg/yr (Vega) and (0.6-0.8) deg/yr (Epsilon
Eri) -- a prediction that can be tested on a timescale of several years.

</DOC>
<DOC>
<DOCNO> 121093 </DOCNO>
The Impact of Adaptive Optics on Star Formation Research


  In this paper, we discuss the benefits of ground-based, adaptive optics (AO)
aided observations for star formation research. After outlining the general
advantages, we present results obtained during the ALFA science demonstration
programme in 1999. These results underline the absolute necessity of AO
assistance for almost any kind of observations regarding star formation
regions.

</DOC>
<DOC>
<DOCNO> 121700 </DOCNO>
Sub-mm imaging of a proto-cluster region at z=3.09


  We have used the Submillimetre Common-User Bolometer Array (SCUBA) detector
on the James Clerk Maxwell Telescope (JCMT) to measure bright sub-mm emission
associated with a recently discovered extensive (>100/h kpc) and highly
luminous, `blob' of Ly-alpha emission at z=3.09. The blob lies within a known
large overdensity of optical sources in the z=3.07-3.11 range, and is centered
on a locally overdense peak within this region. The best explanation for the
copious sub-mm emission is a dust obscured continuum source, which may produce
the ionizing flux for the Ly-alpha cloud. Cooling gas explanations are
plausible but excessively complicated, and the 450/850 micron ratio rules out a
significant fraction of the signal arising from the Sunyaev-Zel'dovich
increment. At least two additional ~10 mJy sub-mm detections in the SCUBA map,
with a surface density significantly higher than in blank field surveys,
suggests that they may be associated with the z=3.09 structure. A SCUBA
`photometry' observation of a second nearby Ly-alpha blob tentatively detects a
weaker sub-mm counterpart.

</DOC>
<DOC>
<DOCNO> 117885 </DOCNO>
ROSAT HRI catalogue of X-ray sources in the LMC region


  All 543 pointed observations of the ROSAT High Resolution Imager (HRI) with
exposure times higher than 50 sec in a field of 10 deg x 10 deg covering the
Large Magellanic Cloud (LMC) were analyzed. A catalogue was produced containing
397 X-ray sources with their properties measured by the HRI. The list was
cross-correlated with the ROSAT Position Sensitive Propotional Counter (PSPC)
source catalogue presented by Haberl & Pietsch (1999), the SIMBAD data base,
and the TYCHO catalogue. 138 HRI sources are contained in the PSPC catalogue.
The spatial resolution of the HRI was higher than that of the PSPC and the
source position could be determined with errors mostly smaller than 15 arcsec
which are dominated by systematic attitude errors. 94 HRI sources were
identified with known objects based on their positional coincidence and X-ray
properties. The catalogue contains 39 foreground stars, 24 supernova remnants
(SNRs), five supersoft sources (SSSs), nine X-ray binaries (XBs), and nine AGN
well known from literature. Another eight sources were identified with known
candidates for these source classes. Additional 21 HRI sources are suggested in
the present work as candidates for SNR, X-ray binary in the LMC, or background
AGN because of their extent, hardness ratios, X-ray to optical flux ratio, or
flux variability.

</DOC>
<DOC>
<DOCNO> 9479 </DOCNO>
Nuclear Spin Relaxation in Hole Doped Two-Leg Ladders


  The nuclear spin-lattice relaxation rate ($1/T_{1}$) has been measured in the
single crystals of hole doped two-leg ladder compounds
Sr$_{14-x}$Ca$_{x}$Cu$_{24}$O$_{41}$ and in the undoped parent material
La$_6$Ca$_8$Cu$_{24}$O$_{41}$. Comparison of $1/T_{1}$ at the Cu and the two
distinct oxygen sites revealed that the major spectral weight of low frequency
spin fluctuations is located near $q \sim (\pi, \pi)$ for most of the
temperature and doping ranges investigated. Remarkable difference in the
temperature dependence of $1/T_1$ for the two oxygen sites in the heavily doped
$x$=12 sample revealed reduction of singlet correlations between two legs in
place of growing antiferromagnetic correlations along the leg direction with
increasing temperature. Such behavior is most likely caused by the dissociation
of bound hole pairs.

</DOC>
<DOC>
<DOCNO> 70290 </DOCNO>
Quantum Phase Transitions and the Extended Coupled Cluster Method


  We discuss the application of an extended version of the coupled cluster
method to systems exhibiting a quantum phase transition. We use the lattice
O(4) non-linear sigma model in (1+1)- and (3+1)-dimensions as an example. We
show how simple predictions get modified, leading to the absence of a phase
transition in (1+1) dimensions, and strong indications for a phase transition
in (3+1) dimensions.

</DOC>
<DOC>
<DOCNO> 84948 </DOCNO>
Schwarzschild metrics and quasi-universes


  The exterior and interior Schwarzschild solutions are rewritten replacing the
usual radial variable with an angular one. This allows to obtain some results
otherwise less apparent or even hidden in other coordinate systems.

</DOC>
<DOC>
<DOCNO> 39805 </DOCNO>
Strong coupling constant from $\tau$ decay within renormalization scheme


  We extract a numerical value for the strong coupling constant \alpha_s from
the \tau-lepton decay rate into nonstrange particles. A new feature of our
procedure is the explicit use of renormalization scheme invariance in
analytical form in order to perform the actual analysis in a particular
renormalization scheme. For the reference coupling constant in the
\MSsch-scheme we obtain \alpha_s(M_\tau)= 0.3184 \pm 0.0060_{exp} which
corresponds to \al_s(M_Z)= 0.1184 \pm 0.0007_{exp} \pm 0.0006_{hq mass}. This
new numerical value is smaller than the standard value from $\tau$-data quoted
in the literature and is closer to \al_s(M_Z)-values obtained from high energy
experiments.

</DOC>
<DOC>
<DOCNO> 152415 </DOCNO>
Symmetries and Compactifications of (4,0) Conformal Gravity


  The free (4,0) superconformal theory in 6 dimensions and its toroidal
dimensional reductions are studied. The reduction to four dimensions on a
2-torus has an $SL(2,\Z)$ duality symmetry that acts non-trivially on the
linearised gravity sector, interchanging the linearised Einstein equations and
Bianchi identities and giving a self-duality between strong and weak coupling
regimes. The possibility of this extending to an interacting form of the theory
is discussed and implications for the non-geometric picture of gravity that
could emerge are considered.

</DOC>
<DOC>
<DOCNO> 69891 </DOCNO>
Testing the Randall-Sundrum Model at a High Energy $e^- e^-$ Collider


  We study the process $e^- e^- \to e^- e^-$ at a high energy $e^- e^-$
collider including the effect of graviton exchanges in the warped gravity model
of Randall and Sundrum. Discovery limits for gravitons are established and the
effects of polarization are discussed.

</DOC>
<DOC>
<DOCNO> 169718 </DOCNO>
Test of quantum nonlocality for cavity fields


  There have been studies on formation of quantum-nonlocal states in spatially
separate two cavities. We suggest a nonlocal test for the field prepared in the
two cavities. We couple classical driving fields with the cavities where a
nonlocal state is prepared. Two independent two-level atoms are then sent
through respective cavities to interact off-resonantly with the cavity fields.
The atomic states are measured after the interaction. Bell's inequality can be
tested by the joint probabilities of two-level atoms being in their excited or
ground states. We find that quantum nonlocality can also be tested using a
single atom sequentially interacting with the two cavities. Potential
experimental errors are also considered. We show that with the present
experimental condition of 5% error in the atomic velocity distribution, the
violation of Bell's inequality can be measured.

</DOC>
<DOC>
<DOCNO> 102603 </DOCNO>
Quantum error-correcting codes associated with graphs


  We present a construction scheme for quantum error correcting codes. The
basic ingredients are a graph and a finite abelian group, from which the code
can explicitly be obtained. We prove necessary and sufficient conditions for
the graph such that the resulting code corrects a certain number of errors.
This allows a simple verification of the 1-error correcting property of
fivefold codes in any dimension. As new examples we construct a large class of
codes saturating the singleton bound, as well as a tenfold code detecting 3
errors.

</DOC>
<DOC>
<DOCNO> 12357 </DOCNO>
Exact Finite-Size-Scaling Corrections to the Critical Two-Dimensional


  We analyze the finite-size corrections to the energy and specific heat of the
critical two-dimensional spin-1/2 Ising model on a torus. We extend the
analysis of Ferdinand and Fisher to compute the correction of order L^{-3} to
the energy and the corrections of order L^{-2} and L^{-3} to the specific heat.
We also obtain general results on the form of the finite-size corrections to
these quantities: only integer powers of L^{-1} occur, unmodified by logarithms
(except of course for the leading $\log L$ term in the specific heat); and the
energy expansion contains only odd powers of L^{-1}. In the specific-heat
expansion any power of L^{-1} can appear, but the coefficients of the odd
powers are proportional to the corresponding coefficients of the energy
expansion.

</DOC>
<DOC>
<DOCNO> 12887 </DOCNO>
Quantum interference and the formation of the proximity effect in


  We discuss a number of basic physical mechanisms relevant to the formation of
the proximity effect in superconductor/normal metal (SN) systems. Specifically,
we review why the proximity effect sharply discriminates between systems with
integrable and chaotic dynamics, respectively, and how this feature can be
incorporated into theories of SN systems. Turning to less well investigated
terrain, we discuss the impact of quantum diffractive scattering on the
structure of the density of states in the normal region. We consider ballistic
systems weakly disordered by pointlike impurities as a test case and
demonstrate that diffractive processes akin to normal metal weak localization
lead to the formation of a hard spectral gap -- a hallmark of SN systems with
chaotic dynamics. Turning to the more difficult case of clean systems with
chaotic boundary scattering, we argue that semiclassical approaches, based on
classifications in terms of classical trajectories, cannot explain the gap
phenomenon. Employing an alternative formalism based on elements of
quasiclassics and the ballistic $\sigma$-model, we demonstrate that the inverse
of the so-called Ehrenfest time is the relevant energy scale in this context.
We discuss some fundamental difficulties related to the formulation of low
energy theories of mesoscopic chaotic systems in general and how they prevent
us from analysing the gap structure in a rigorous manner. Given these
difficulties, we argue that the proximity effect represents a basic and
challenging test phenomenon for theories of quantum chaotic systems.

</DOC>
<DOC>
<DOCNO> 84131 </DOCNO>
Gyroscope precession in cylindrically symmetric spacetimes


  We present calculations of gyroscope precession in spacetimes described by
Levi-Civita and Lewis metrics, under different circumstances. By doing so we
are able to establish a link between the parameters of the metrics and
observable quantities, providing thereby a physical interpretation for those
parameters, without specifying the source of the field.

</DOC>
<DOC>
<DOCNO> 152286 </DOCNO>
Generating Functional and Large N-Limit of Nonlocal 2D Generalized


  Using the path integral method, we calculate the partition function and
generating functional (of the field strengths) on the nonlocal generalized 2D
Yang - Mills theories ($nlgYM_2$'s), which is nonlocal in auxiliary field [14].
Our calculations is done for general surfaces. We find a general expression for
free energy of $W(\phi) = \phi^{2k}$ in $nlgYM_2$ theories at the strong
coupling phase (SCP) regime ($A > A_c$) for large groups. In the specific
$\phi^4$ model, we show that the theory has a third order phase transition.

</DOC>
<DOC>
<DOCNO> 118085 </DOCNO>
The Discovery of an Embedded Cluster of High-Mass Stars Near SGR 1900+14


  Deep I-band imaging to approximately I = 26.5 of the soft gamma-ray repeater
SGR 1900+14 region has revealed a compact cluster of massive stars located only
a few arcseconds from the fading radio source thought to be the location of the
SGR (Frail, Kulkarni, & Bloom 1999). This cluster was previously hidden in the
glare of the pair of M5 supergiant stars (whose light was removed by PSF
subtraction) proposed by Vrba et al. (1996) as likely associated with the SGR
1900+14. The cluster has at least 13 members within a cluster radius of
approximately 0.6 pc, based on an estimated distance of 12-15 kpc. It is
remarkably similar to a cluster found associated with SGR 1806-20 (Fuchs et al.
1999). That similar clusters have now been found at or near the positions of
the two best-studied SGRs suggests that young neutron stars, thought to be
responsible for the SGR phenomenon, have their origins in proximate compact
clusters of massive stars.

</DOC>
<DOC>
<DOCNO> 152192 </DOCNO>
Antifield BRST quantization of duality-symmetric Maxwell theory


  We perform the antifield BRST quantization of duality-symmetric Maxwell
theory and show explicitly the quantum equivalence of the different
formulations (covariant and non-covariant). The non-covariant gauge-fixed
action is used in the computation of propagators for this model.

</DOC>
<DOC>
<DOCNO> 119170 </DOCNO>
Microlensing of multiply-imaged compact radio sources: Evidence for


  We present the first unambiguous case of external variability of a radio
gravitational lens, CLASS B1600+434. The VLA 8.5-GHz difference light curve of
the lensed images, taking the proper time-delay into account, shows the
presence of external variability with 14.6-sigma confidence. We investigate two
plausible causes of this external variability: scattering by the ionized
component of the Galactic interstellar medium and microlensing by massive
compact objects in the bulge/disk and halo of the lens galaxy. Based on the
tight relation between the modulation-index and variability time scale and the
quantitative difference between the light curves of both lensed images, we
conclude that the observed short-term variability characteristics of the lensed
images are incompatible with scintillation in our Galaxy. This conclusion is
strongly supported by multi-frequency WSRT observations at 1.4 and 5 GHz, which
are in strong disagreement with predictions based on the scintillation
hypothesis. ... On the other hand, a single superluminal jet-component, having
an apparent velocity 9<=(v_app/c)<=26, a radius of 2-5 micro-arcsec and
containing 5-11% of the observed 8.5-GHz source flux density, can reproduce the
observed modulation-indices and variability time scale at 8.5 GHz, when it is
microlensed by compact objects in the lens galaxy. It also reproduces the
frequency-dependence of the modulation-indices, determined from the independent
WSRT 1.4 and 5-GHz observations. ... The only conclusion fully consistent with
the data gathered thus far is that we have indeed detected radio microlensing.
The far reaching consequence of this statement is that a significant fraction
of the mass in the dark-matter halo at ~6 kpc (h=0.65) above the lens-galaxy
disk in B1600+434 consists of massive compact objects. [abridged]

</DOC>
<DOC>
<DOCNO> 150669 </DOCNO>
One particular approach to the non-equilibrium quantum dynamics


  We present a particular approach to the non-equilibrium dynamics of quantum
field theory. This approach is based on the Jaynes-Gibbs principle of the
maximal entropy and its implementation, throghout the initial value data, into
the dynamical equations for Green's functions.

</DOC>
<DOC>
<DOCNO> 150514 </DOCNO>
Supersymmetric Pair Correlation Function of Wilson Loops


  We give a path integral derivation of the annulus diagram in a supersymmetric
theory of open and closed strings with Dbranes. We compute the pair correlation
function of Wilson loops in the generic weakly coupled supersymmetric flat
spacetime background with Dbranes. We obtain a -u^4/r^9 potential between heavy
nonrelativistic sources in a supersymmetric gauge theory at short distances.

</DOC>
<DOC>
<DOCNO> 170496 </DOCNO>
The effects of time delays in adaptive phase measurements


  It is not possible to make measurements of the phase of an optical mode using
linear optics without introducing an extra phase uncertainty. This extra phase
variance is quite large for heterodyne measurements, however it is possible to
reduce it to the theoretical limit of $\log \bar n/(4\bar n^2)$ using adaptive
measurements. These measurements are quite sensitive to experimental
inaccuracies, especially time delays and inefficient detectors. Here we show
that the minimum introduced phase variance when there is a time delay of $\tau$
is $\tau/(8\bar n)$. We verify this result numerically, showing that the
introduced phase variance approaches this limit for most of the adaptive
schemes using the best final phase estimate. The main exception is the adaptive
mark II scheme with simplified feedback, which is extremely sensitive to time
delays. We also consider the extra phase variance due to time delays for the
mark I case with simplified feedback, verifying the $\tau /2$ result obtained
in [W{\sc iseman}, H. M., and K{\sc illip}, R. B., 1997, {\it Phys. Rev. A}
{\bf 56}, 944] both by a more rigorous analytic technique and numerically.

</DOC>
<DOC>
<DOCNO> 13807 </DOCNO>
Theory of spin wave excitations of metallic A-type antiferromagnetic


  The spin dynamic of the metallic A-type antiferromagnetic manganites is
studied. An effective nearest-neighbour Heisenberg spin wave dispersion is
derived from the double exchange model taking into account the superexchange
interaction between the core spins. The result of inelastic neutron scattering
experiment on ${Nd}_{0.45}{Sr}_{0.55}{Mn} {O}_{3}$ is qualitatively reproduced.
Comparing theory with experimental data two main parameters of the model:
nearest-neighbour electron transfer amplitude and superexchange coupling
between the core spins are estimated.

</DOC>
<DOC>
<DOCNO> 71232 </DOCNO>
Neutrino Mass: The Present and the Future


  We argue that the evidence for neutrino mass is quite compelling. This mass
raises a number of questions, which we enumerate, about neutrinos. Then we
focus on one of these questions---the issue of the possible neutrino mass
spectra. In particular, we explain that one can have a four-neutrino spectrum
which does not require significant sterile-neutrino involvement in either the
atmospheric or solar neutrino oscillations.

</DOC>
<DOC>
<DOCNO> 40073 </DOCNO>
Production of Single W Bosons at \sqrt{s}=189 GeV and Measurement of


  Single W boson production in electron-positron collisions is studied with the
L3 detector at LEP. The data sample collected at a centre-of-mass energy of
\sqrt{s} = 188.7GeV corresponds to an integrated luminosity of 176.4pb^-1.
Events with a single energetic lepton or two acoplanar hadronic jets are
selected. Within phase-space cuts, the total cross-section is measured to be
0.53 +/- 0.12 +/- 0.03 pb, consistent with the Standard Model expectation.
Including our single W boson results obtained at lower \sqrt{s}, the WWgamma
gauge couplings kappa_gamma and lambda_gamma are determined to be kappa_gamma =
0.93 +/- 0.16 +/- 0.09 and lambda_gamma = -0.31 +0.68 -0.19 +/- 0.13.

</DOC>
<DOC>
<DOCNO> 123044 </DOCNO>
Runaway Collisions in Star Clusters


  We study the occurrence of physical collisions between stars in young and
compact star cluster. The calculations are performed on the GRAPE-4 with the
starlab software environment which include the dynamical evolution and the
nuclear evolution of all stars and binaries. The selection of the initial
conditions is based on existing and well observed star clusters, such as R136
in the 30 Doradus region in the Large Magellanic Cloud and the Arches and
Quintuplet star clusters in the vicinity of the Galactic center.
  Collisions between stars occurred rather frequently in our models. At any
time a single star dominates the collision history of the system. The collision
rate of this runaway merger scales with the initial relaxation time of the
cluster and is independent on other cluster parameters, such as the initial
mass function or the initial density profile of the cluster. Subsequent
encounters result in a steady grow in mass of the coagulating star, until it
escapes or explodes in a supernova. The collision rate in these models is about
0.00022 collisions per star per Myr for a cluster with an initial relaxation
time of 1 Myr.

</DOC>
<DOC>
<DOCNO> 71133 </DOCNO>
J/psi absorption by pi and rho mesons in a meson exchange model with


  We reanalyze the dissociation process of the $J/\psi$ by $\pi$ and $\rho$
mesons into $D + \bar{D}$, $D^* + \bar{D}$, $D + \bar{D}^*$, and $D^* +
\bar{D}^*$ within a meson exchange model. In addition to the dissociation
mechanisms considered in the literature, we consider anomalous parity
interactions, whose couplings are constrained by heavy quark spin symmetry and
phenomenology. This opens new dissociation channels and adds new diagrams in
the previously considered processes. Compared to the previous results, we find
that these new additions have only a minor effect on the $\rho + J/\psi$ total
inelastic cross section, but reduce the one for $\pi + J/\psi$ by about 50 %
near the threshold.

</DOC>
<DOC>
<DOCNO> 11803 </DOCNO>
Emergence of Irrationality: Magnetization Plateaux in Modulated Hubbard


  Hubbard chains with periodically modulated coupling constants in a magnetic
field exhibit gaps at zero temperature in their magnetic and charge excitations
in a variety of situations. In addition to fully gapped situations (plateau in
the magnetization curve and charge gap), we have shown [cond-mat/9908398] that
plateaux also appear in the presence of massless modes, leading to a plateau
with a magnetization m whose value depends continuously on the filling n. Here
we detail and extend the arguments leading to such doping-dependent
magnetization plateaux. First we analyze the low-lying excitations using
Abelian bosonization. We compute the susceptibility and show that due to the
constraint of fixed n, it vanishes at low temperatures (thus leading to a
magnetization plateau) even in the presence of one massless mode. Next we study
correlation functions and show that one component of the superconducting order
parameter develops quasi-long-range order on a doping-dependent magnetization
plateau. We then use perturbation theory in the on-site repulsion U to compute
the width of these plateaux up to first order in U. Finally, we compute
groundstate phase diagrams and correlation functions by Lanczos diagonalization
of finite clusters, confirming the presence of doping-dependent plateaux and
their special properties.

</DOC>
<DOC>
<DOCNO> 8297 </DOCNO>
Random deaths in a computational model for age-structured populations


  The concept of random deaths in a computational model for population dynamics
is critically examined. We claim that it is just an artifact, albeit useful, of
computational models to limit the size of the populations and has no biological
foundation. Alternative implementations of random deaths strategies are
discussed and compared.

</DOC>
<DOC>
<DOCNO> 151191 </DOCNO>
Unifying Themes in Topological Field Theories


  We discuss unifying features of topological field theories in 2, 3 and 4
dimensions. This includes relations among enumerative geometry (2d topological
field theory) link invariants (3d Chern-Simons theory) and Donaldson invariants
(4d topological theory).

</DOC>
<DOC>
<DOCNO> 151616 </DOCNO>
Expansion in the distance parameter for two vortices close together


  Static vortices close together are studied for two different models in
2-dimen- sional Euclidean space. In a simple model for one complex field an
expansion in the parameters describing the relative position of two vortices
can be given in terms of trigonometric and exponential functions. The results
are then compared to those of the Ginzburg-Landau theory of a superconductor in
a magnetic field at the point between type-I and type-II superconductivity. For
the angular dependence a similar pattern emerges in both models. The
differences for the radial functions are studied up to third order.

</DOC>
<DOC>
<DOCNO> 119063 </DOCNO>
The Ionization of the Local Interstellar Medium, as Revealed by FUSE


  FUSE spectra of the white dwarf stars G191-B2B, GD 394, WD 2211-495 and WD
2331-475 cover the absorption features out of the ground electronic states of N
I, N II, N III, O I and Ar I in the far ultraviolet, providing new insights on
the origin of the partial ionization of the Local Interstellar Medium (LISM),
and for the case of G191-B2B, the interstellar cloud that immediately surrounds
the solar system. Toward these targets the interstellar abundances of Ar I, and
sometimes N I, are significantly below their cosmic abundances relative to H I.
In the diffuse interstellar medium, these elements are not likely to be
depleted onto dust grains. Generally, we expect that Ar should be more strongly
ionized than H (and also O and N whose ionizations are coupled to that of H via
charge exchange reactions) because the cross section for the photoionization of
Ar I is very high. Our finding that Ar I/H I is low may help to explain the
surprisingly high ionization of He in the LISM found by other investigators.
Our result favors the interpretation that the ionization of the local medium is
maintained by a strong EUV flux from nearby stars and hot gases, rather than an
incomplete recovery from a past, more highly ionized condition.

</DOC>
<DOC>
<DOCNO> 100127 </DOCNO>
Boundary knot method: A meshless, exponential convergence,


  Based on the radial basis function (RBF), non-singular general solution and
dual reciprocity principle (DRM), this paper presents an inheretnly meshless,
exponential convergence, integration-free, boundary-only collocation techniques
for numerical solution of general partial differential equation systems. The
basic ideas behind this methodology are very mathematically simple and
generally effective. The RBFs are used in this study to approximate the
inhomogeneous terms of system equations in terms of the DRM, while non-singular
general solution leads to a boundary-only RBF formulation. The present method
is named as the boundary knot method (BKM) to differentiate it from the other
numerical techniques. In particular, due to the use of non-singular general
solutions rather than singular fundamental solutions, the BKM is different from
the method of fundamental solution in that the former does no need to introduce
the artificial boundary and results in the symmetric system equations under
certain conditions. It is also found that the BKM can solve nonlinear partial
differential equations one-step without iteration if only boundary knots are
used. The efficiency and utility of this new technique are validated through
some typical numerical examples. Some promising developments of the BKM are
also discussed.

</DOC>
<DOC>
<DOCNO> 121419 </DOCNO>
Resolving the Mystery of X-ray Faint Elliptical Galaxies: Chandra X-ray


  Chandra observations of the X-ray faint elliptical galaxy NGC 4697 resolve
much of the X-ray emission (61% within one effective radius) into ~80 point
sources, of which most are low mass X-ray binaries (LMXBs). These LMXBs provide
the bulk of the hard emission and much of the soft emission as well. Of the
remaining unresolved emission, it is likely that about half is from fainter
LMXBs, while the other half (~23% of the total emission) is from interstellar
gas. Three of the resolved sources are supersoft sources. In the outer regions
of NGC 4697, eight of the LMXBs (about 25%) are coincident with candidate
globular clusters, which indicates that globulars have a high probability of
containing X-ray binaries compared to the normal stellar population. The X-ray
luminosities (0.3-10 keV) of the resolved LMXBs range from ~5e37 to ~2.5e39
ergs/s. The luminosity function of the LMXBs has a "knee" at 3.2e38 ergs/s,
which is roughly the Eddington luminosity of a 1.4 M_sun neutron star (NS);
this knee might be useful as a distance indicator. The highest luminosity
source has the Eddington luminosity of a ~20 M_sun black hole (BH). The
presence of this large population of NS and massive BH stellar remnants in this
elliptical galaxy shows that it (or its progenitors) once contained a large
population of massive main sequence stars.

</DOC>
<DOC>
<DOCNO> 170511 </DOCNO>
Analysis of Generalized Grover's Quantum Search Algorithms Using


  The recursion equation analysis of Grover's quantum search algorithm
presented by Biham et al. [PRA 60, 2742 (1999)] is generalized. It is applied
to the large class of Grover's type algorithms in which the Hadamard transform
is replaced by any other unitary transformation and the phase inversion is
replaced by a rotation by an arbitrary angle. The time evolution of the
amplitudes of the marked and unmarked states, for any initial complex amplitude
distribution is expressed using first order linear difference equations. These
equations are solved exactly. The solution provides the number of iterations T
after which the probability of finding a marked state upon measurement is the
highest, as well as the value of this probability, P_max. Both T and P_max are
found to depend on the averages and variances of the initial amplitude
distributions of the marked and unmarked states, but not on higher moments.

</DOC>
<DOC>
<DOCNO> 174453 </DOCNO>
New Limit for the Half-Life of 2K(2neutrino)-Capture Decay Mode of 78Kr


  Features of data accumulated at 1817 hours in the experimental search for
2K(2 \nu)-capture decay mode of Kr-78 are discussed. The new limit for this
decay half-life is found to be T_{1/2} > 2.3 *10^{20} yr. (90% C.L.).

</DOC>
<DOC>
<DOCNO> 85024 </DOCNO>
The rotational modes of relativistic stars: Analytic results


  We study the r-modes and rotational ``hybrid'' modes of relativistic stars.
As in Newtonian gravity, the spectrum of low-frequency rotational modes is
highly sensitive to the stellar equation of state. If the star and its
perturbations obey the same one-parameter equation of state (as with isentropic
stars), there exist {\it no pure r-modes at all} - no modes whose limit, for a
star with zero angular velocity, is an axial-parity perturbation. Rotating
stars of this kind similarly have no pure g-modes, no modes whose spherical
limit is a perturbation with polar parity and vanishing perturbed pressure and
density. We compute the post-Newtonian corrections to the $l=m$ r-modes of
isentropic and non-isentropic uniform density stars.

</DOC>
<DOC>
<DOCNO> 83216 </DOCNO>
Improving Testsuites via Instrumentation


  This paper explores the usefulness of a technique from software engineering,
namely code instrumentation, for the development of large-scale natural
language grammars. Information about the usage of grammar rules in test
sentences is used to detect untested rules, redundant test sentences, and
likely causes of overgeneration. Results show that less than half of a
large-coverage grammar for German is actually tested by two large testsuites,
and that 10-30% of testing time is redundant. The methodology applied can be
seen as a re-use of grammar writing knowledge for testsuite compilation.

</DOC>
<DOC>
<DOCNO> 122492 </DOCNO>
Data Analysis for the Microwave Anisotropy Probe (MAP) Mission


  We present an overview of the upcoming Microwave Anisotropy Probe (MAP)
mission, with an emphasis on those aspects of the mission that simplify the
data analysis. The method used to make sky maps from the differential
temperature data is reviewed and we present some of the noise properties
expected from these maps. An overview of the method we plan to use to mine the
angular power spectrum from the mega-pixel sky maps closes the paper.

</DOC>
<DOC>
<DOCNO> 70403 </DOCNO>
Heavy sterile neutrinos: Bounds from big-bang nucleosynthesis and SN


  Cosmological and astrophysical effects of heavy (10 - 200 MeV) sterile Dirac
neutrinos, mixed with the active ones, are considered. The bounds on mass and
mixing angle from both supernovae and big-bang nucleosynthesis are presented.

</DOC>
<DOC>
<DOCNO> 68444 </DOCNO>
Gluon distributions in nucleons and pions at a low resolution scale


  In this paper we study the gluon distribution functions in nucleons and pions
at a low resolution $Q^2$ scale. This is an important issue since parton
densities at low $Q^2$ have always been taken as an external input which is
adjusted through DGLAP evolution to fit the experimental data at higher scales.
Here, in the framework of a model recently developed, it is shown that the
hypothetical cloud of {\it neutral} pions surrounding nucleons and pions
appears to be responsible for the characteristic valence-like gluon
distributions needed at the inital low scale. As an additional result, we get
the remarkable prediction that neutral and charged pions have different
intrinsic sea flavor contents.

</DOC>
<DOC>
<DOCNO> 10050 </DOCNO>
Spectral Functions for the Tomonaga-Luttinger and Luther-Emery Liquids


  We calculate the finite temperature single hole spectral function and the
spin dynamic structure factor of spinfull one-dimensional Tomonaga-Luttinger
liquid. Analytical expressions are obtained for a number of special cases. We
also calculate the single hole spectral function of a spin gapped Luther-Emery
liquid and obtain exact results at the free fermion point K_s=1/2. These
results may be applied to the analysis of angle resolved photoemission and
neutron scattering experiments on quasi-one-dimensional materials.

</DOC>
<DOC>
<DOCNO> 120188 </DOCNO>
High Resolution X-Ray Spectra of Capella: Initial Results from the


  High resolution spectra of the active binary Capella (G8 III + G1 III)
covering the energy range 0.4-8.0 keV (1.5-30 Angstroms) show a large number of
emission lines, demonstrating the performance of the HETGS. A preliminary
application of plasma diagnostics provides information on coronal temperatures
and densities. Lines arising from different elements in a range of ionization
states indicate that Capella has plasma with a broad range of temperatures,
from log T = 6.3 to 7.2, generally consistent with recent results from
observations with the Extreme Ultraviolet Explorer (EUVE) and the Advanced
Satellite for Cosmology and Astrophysics (ASCA). The electron density is
determined from He-like O VII lines, giving the value N_e=10^10 cm^-3 at
T_e=2*10^6 K; He-like lines formed at higher temperatures give only upper
limits to the electron density. The density and emission measure from O VII
lines together indicate that the coronal loops are significantly smaller than
the stellar radius.

</DOC>
<DOC>
<DOCNO> 121355 </DOCNO>
A Comparison of Simulated and Analytic Major Merger Counts


  We use large volume, high resolution, N-body simulations of 3 different
$\Lambda$CDM models, with different clustering strengths, to generate dark
matter halo merging histories. Over the reliable range of halo masses, roughly
galaxy groups to rich clusters of galaxies, we quantify the number density of
major mergers for two different time intervals and compare with analytic
predictions based on the extended Press-Schechter (1974) theory.

</DOC>
<DOC>
<DOCNO> 102524 </DOCNO>
On a Relative Version of Fujita's Freeness Conjecture


  We consider Fujita's freeness conjecture in a relative setting and prove a
criterion by proving a correct Q-divisor version of the Kollar vanishing
theorem.

</DOC>
<DOC>
<DOCNO> 117659 </DOCNO>
Halo Profiles and the Nonlinear Two- and Three-Point Correlation


  We investigate the nonlinear two- and three-point correlation functions of
the cosmological density field in Fourier space and test the popular
hierarchical clustering model, that the three-point amplitude Q is independent
of scale. In high-resolution N-body simulations of both n=-2 scale-free and
cold dark matter models, we find that Q at late times is not constant but
increases with wavenumber far into the nonlinear regime. Self-similar scaling
also does not hold as rigorously for the three-point function as for the
two-point function in the n=-2 simulation, perhaps a manifestation of the
finite simulation volume. We suggest that a better understanding of the two-
and three-point correlation functions in the nonlinear regime lies in the link
to the density profiles of dark matter halos. We demonstrate and quantify how
the slopes of the correlation functions are affected by the slope of the halo
profiles using simple halo shapes and analytic clustering models.

</DOC>
<DOC>
<DOCNO> 101501 </DOCNO>
A variational principle for domino tilings


  We formulate and prove a variational principle (in the sense of
thermodynamics) for random domino tilings, or equivalently for the dimer model
on a square grid. This principle states that a typical tiling of an arbitrary
finite region can be described by a function that maximizes an entropy
integral. We associate an entropy to every sort of local behavior domino
tilings can exhibit, and prove that almost all tilings lie within epsilon (for
an appropriate metric) of the unique entropy-maximizing solution. This gives a
solution to the dimer problem with fully general boundary conditions, thereby
resolving an issue first raised by Kasteleyn. Our methods also apply to dimer
models on other grids and their associated tiling models, such as tilings of
the plane by three orientations of unit lozenges.

</DOC>
<DOC>
<DOCNO> 152042 </DOCNO>
RG flows on the phase spaces and the $\tau$ functions for the generic


  We discuss the generic definition of the $\tau$ function for the arbitrary
Hamiltonian system. The different approaches concerning the deformations of the
curves and surfaces are compared. It is shown that the Baker-Akhiezer function
for the secondary integrable system of the Toda lattice type can be identified
with the coherent wave function of the initial dynamical system. The $\tau$
function appears to be related to the filling of the interior of the classical
trajectory by coherent states. Transition from dispersionless to dispersionful
Toda lattice corresponds to the quantization of the initial dynamical system.

</DOC>
<DOC>
<DOCNO> 69886 </DOCNO>
Relationship between the quark condensate and low-energy Pi-Pi


  The two-flavor Gell-Mann-Oakes-Renner ratio is expressed in terms of
low-energy pi-pi observables including the O(p^6) double chiral logarithms,
computed in Generalized Chiral Perturbation Theory. It is found that their
contribution is important and tends to compensate the one from the single
chiral logarithms.

</DOC>
<DOC>
<DOCNO> 10633 </DOCNO>
Resonances in the dynamics of $\phi^4$ kinks perturbed by ac forces


  We study the dynamics of $\phi^4$ kinks perturbed by an ac force, both with
and without damping. We address this issue by using a collective coordinate
theory, which allows us to reduce the problem to the dynamics of the kink
center and width. We carry out a careful analysis of the corresponding ordinary
differential equations, of Mathieu type in the undamped case, finding and
characterizing the resonant frequencies and the regions of existence of
resonant solutions. We verify the accuracy of our predictions by numerical
simulation of the full partial differential equation, showing that the
collective coordinate prediction is very accurate. Numerical simulations for
the damped case establish that the strongest resonance is the one at half the
frequency of the internal mode of the kink. In the conclusion we discuss on the
possible relevance of our results for other systems, especially the sine-Gordon
equation. We also obtain additional results regarding the equivalence between
different collective coordinate methods applied to this problem.

</DOC>
<DOC>
<DOCNO> 123200 </DOCNO>
Stellar features in integrated starburst spectra as stellar population


  We review the main stellar features observed in starburst spectra from the UV
to the near-IR and their use as fundamental tools to determine the properties
of stellar populations from integrated spectra.
  The origin and dependence of the features on stellar properties are
discussed, and we summarise existing modeling techniques used for quantitative
analysis.
  Recent results from studies based on UV, optical and near-IR observations of
starbursts and active galaxies are summarised. Finally, we briefly discuss
combined starburst + photoionisation models including also observations from
nebular emission lines. The present review is complementary to the recent
summary by Schaerer (2000) (http://xxx.lpthe.jussieu.fr/abs/astro-ph/0007307)
discussing more extensively nebular analysis of starbursts and related objects.

</DOC>
<DOC>
<DOCNO> 121156 </DOCNO>
The Global-Normal Disk Oscillations and the Persistent Low Frequency QPO


  We suggest that persistent low-frequency quasi-periodic oscillations (QPOs)
detected in X-ray, ultraviolet, optical energy ranges the black hole (BH)
sources XTE J1118+480, GRO J1655-40 LMC X-1 at ~ 0.1 Hz, and QPOs in HZ Her/Her
X-1 at ~ 0.05 Hz and in Neutron Star (NS) binaries 4U 1323-62, 4U 1746-31 and
EXO 0748-76 at ~ 1 Hz are caused by the global disk oscillations in the
direction normal to the disk (normal mode). We argue that these disk
oscillations are a result of the gravitational interaction between the central
compact object and the disk. A small displacement of the disk from the
equatorial plane results in a linear gravitational restoring force opposite to
this displacement. Our analysis shows that the frequency of this mode is a
function of the mass of the central object and it also depends on the inner and
outer radii of the disk which in turn are related to the rotation period of the
binary system. We derive an analytical formula for the frequency of the normal
disk mode and show that these frequencies can be related to the persistent
lower QPO frequencies observed in the NS and BH sources. We offer a new
independent approach to the black hole mass determination by interpreting this
low QPO frequency as the global disk oscillation frequency. The implementation
of this method combined with the independent method which uses the X-ray energy
spectra (Shrader & Titarchuk 1999) results in stringent constraints for the
black hole masses.

</DOC>
<DOC>
<DOCNO> 117761 </DOCNO>
Near-Infrared-Spectroscopy with Extremely Large Telescopes:


  Integral-field-spectroscopy and multi-object-spectroscopy provide the high
multiplex gain required for efficient use of the upcoming generation of
extremely large telescopes. We present instrument developments and designs for
both concepts, and how these designs can be applied to cryogenic near-infrared
instrumentation. Specifically, the fiber-based concept stands out the
possibility to expand it to any number of image points, and its modularity
predestines it to become the new concept for multi-field-spectroscopy. Which of
the three concepts --- integral-field-, multi-object-, or
multi-field-spectroscopy --- is best suited for the largest telescopes is
discussed considering the size of the objects and their density on the sky.

</DOC>
<DOC>
<DOCNO> 178532 </DOCNO>
Pseudovector versus pseudoscalar coupling in kaon photoproduction -


  The question of pseudovector versus pseudoscalar coupling schemes for the
kaon-hyperon-nucleon interaction is re-examined for the reaction $\gamma p\to
K^+ \Lambda$ in several isobaric models. These models typically include Born
terms, $K^*$- and $K_1$-exchange in the t-channel, and a few different
combinations of spin-1/2 baryon resonances in the $s$- and $u$-channels. The
coupling constants are obtained by fitting to a large data set. We find that
both pseudoscalar and pseudovector couplings can allow for a satisfactory
description of the present database. The resulting coupling constants,
$g_{K\Lambda N}$ and $g_{K\Sigma N}$, in the pseudovector coupling scheme are
smaller than those predicted using flavor SU(3) symmetry, but consistent with
the values obtained in a QCD sum rule calculation.

</DOC>
<DOC>
<DOCNO> 101787 </DOCNO>
On polarized surfaces of low degree whose adjont bundles are not spanned


  Smooth complex surfaces polarized with an ample and globally generated line
bundle of degree three and four, such that the adjoint bundle is not globally
generated, are considered. Scrolls of a vector bundle over a smooth curve are
shown to be the only examples in degree three. Two classes of examples in
degree four are presented, one of which is shown to characterize regular such
pairs. A Reider-type theorem is obtained in which the assumption on the degree
of the polarization is removed.

</DOC>
<DOC>
<DOCNO> 99856 </DOCNO>
Certain extensions of vertex operator algebras of affine type


  We generalize Feigin and Miwa's construction of extended vertex operator
(super)algebras $A_{k}(sl(2))$ for other types of simple Lie algebras. For all
the constructed extended vertex operator (super)algebras, irreducible modules
are classified, complete reducibility of every module is proved and fusion
rules are determined modulo the fusion rules for vertex operator algebras of
affine type.

</DOC>
<DOC>
<DOCNO> 10949 </DOCNO>
Glassiness and constrained dynamics of a short-range non-disordered spin


  We study the low temperature dynamics of a two dimensional short-range spin
system with uniform ferromagnetic interactions, which displays glassiness at
low temperatures despite the absence of disorder or frustration. The model has
a dual description in terms of free defects subject to dynamical constraints,
and is an explicit realization of the ``hierarchically constrained dynamics''
scenario for glassy systems. We give a number of exact results for the statics
of the model, and study in detail the dynamical behaviour of one-time and
two-time quantities. We also consider the role played by the configurational
entropy, which can be computed exactly, in the relation between fluctuations
and response.

</DOC>
<DOC>
<DOCNO> 8492 </DOCNO>
Convergence of the critical attractor of dissipative maps: Log-periodic


  For a family of logistic-like maps, we investigate the rate of convergence to
the critical attractor when an ensemble of initial conditions is uniformly
spread over the entire phase space. We found that the phase space volume
occupied by the ensemble W(t) depicts a power-law decay with log-periodic
oscillations reflecting the multifractal character of the critical attractor.
We explore the parametric dependence of the power-law exponent and the
amplitude of the log-periodic oscillations with the attractor's fractal
dimension governed by the inflexion of the map near its extremal point.
Further, we investigate the temporal evolution of W(t) for the circle map whose
critical attractor is dense. In this case, we found W(t) to exhibit a rich
pattern with a slow logarithmic decay of the lower bounds. These results are
discussed in the context of nonextensive Tsallis entropies.

</DOC>
<DOC>
<DOCNO> 117814 </DOCNO>
Particle Acceleration at Ultra-Relativistic Shocks and the Spectra of


  We examine Fermi-type acceleration at relativistic shocks, and distinguish
between the initial boost of the first shock crossing cycle, where the energy
gain per particle can be very large, and the Fermi process proper with repeated
shock crossings, in which the typical energy gain is of order unity. We
calculate by means of numerical simulations the spectrum and angular
distribution of particles accelerated by this Fermi process, in particular in
the case where particle dynamics can be approximated as small-angle scattering.
We show that synchrotron emission from electrons or positrons accelerated by
this process can account remarkably well for the observed power-law spectra of
GRB afterglows and Crab-like supernova remnants. In the context of a
decelerating relativistic fireball, we calculate the maximum particle energy
attainable by acceleration at the external blast wave, and discuss the minimum
energy for this acceleration process and its consequences for the observed
spectrum.

</DOC>
<DOC>
<DOCNO> 117175 </DOCNO>
Singular Potentials and Limit Cycles


  We show that a central $1/r^n$ singular potential (with $n\geq 2$) is
renormalized by a one-parameter square-well counterterm; low-energy observables
are made independent of the square-well width by adjusting the square-well
strength. We find a closed form expression for the renormalization-group
evolution of the square-well counterterm.

</DOC>
<DOC>
<DOCNO> 150608 </DOCNO>
Brane World Scenarios and the Cosmological Constant


  Brane world scenarios offer a way of ensuring that a Poincare invariant four
dimensional world can emerge, without fine tuning, as a solution to the
equations of motion of an effective action. We discuss the different ways in
which this happens, and point out that the underlying reason is that there is a
contribution to the effective cosmological constant which is a constant of
integration, that maybe adjusted to ensure a flat space solution. Basically
this is an old idea revived in a new context and we speculate that there may be
string scenarios that provide a concrete realization of it. Finally we discuss
to what extent this is a solution to the cosmological constant problem.

</DOC>
<DOC>
<DOCNO> 122409 </DOCNO>
Detection of anisotropy in the Cosmic Microwave Background at horizon


  BOOMERanG has recently resolved structures on the last scattering surface at
redshift $\sim$ 1100 with high signal to noise ratio. We review the technical
advances which made this possible, and we focus on the current results for maps
and power spectra, with special attention to the determination of the total
mass-energy density in the Universe and of other cosmological parameters.

</DOC>
<DOC>
<DOCNO> 99964 </DOCNO>
Impurity Operators in RSOS Models


  We give a construction of impurity operators in the `algebraic analysis'
picture of RSOS models. Physically, these operators are half-infinite
insertions of certain fusion-RSOS Boltzmann weights. They are the face analogue
of insertions of higher spin lines in vertex models. Mathematically, they are
given in terms of intertwiners of $U(\hat{sl}_2)_q$ modules. We present a
detailed perturbation theory check of the conjectural correspondence between
the physical and mathematical constructions in a particular simple example.

</DOC>
<DOC>
<DOCNO> 150475 </DOCNO>
Boundary Liouville Field Theory I. Boundary State and Boundary Two-point


  Liouville conformal field theory is considered with conformal boundary. There
is a family of conformal boundary conditions parameterized by the boundary
cosmological constant, so that observables depend on the dimensional ratios of
boundary and bulk cosmological constants. The disk geometry is considered. We
present an explicit expression for the expectation value of a bulk operator
inside the disk and for the two-point function of boundary operators. We
comment also on the properties of the degenrate boundary operators. Possible
applications and further developments are discussed. In particular, we present
exact expectation values of the boundary operators in the boundary sin-Gordon
model.

</DOC>
<DOC>
<DOCNO> 68135 </DOCNO>
Dileptons from transport and hydrodynamical models


  Transport and hydrodynamical models used to describe the expansion stage of a
heavy-ion collision at the CERN SPS give different dilepton spectrum even if
they are tuned to reproduce the observed hadron spectra. To understand the
origin of this difference we compare the dilepton emission from transport and
hydrodynamical models using similar initial states in both models. We find that
the requirement of pion number conservation in a hydrodynamical model does not
change the dilepton emission. Also the mass distribution from the transport
model indicates faster cooling and longer lifetime of the fireball.

</DOC>
<DOC>
<DOCNO> 70898 </DOCNO>
QCD at Photon Colliders


  The novel possibilities of probing the photon structure and high energy limit
of QCD at photon colliders are summarised. We discuss the photon structure
function $F_2^{\gamma}(x,Q^2)$, the gluon distribution in the photon and the
spin dependent structure function $g_1^{\gamma}(x,Q^2)$ of the photon and
emphasise advantages of the photon colliders for measuring these quantities.
The possibility of probing the QCD pomeron and odderon in $\gamma\gamma$ and $e
\gamma$ collisions is also described.

</DOC>
<DOC>
<DOCNO> 11504 </DOCNO>
Renormalization group analysis of quantum critical points in d-wave


  We describe a search for renormalization group fixed points which control a
second-order quantum phase transition between a d_{x^2-y^2} superconductor and
some other superconducting ground state. Only a few candidate fixed points are
found. In the finite temperature quantum-critical region of some of these fixed
points, the fermion quasiparticle lifetime is very short and the spectral
function has an energy width of order k_B T near the Fermi points. Under the
same conditions, the thermal conductivity is infinite in the scaling limit. We
thus provide simple, explicit, examples of quantum theories in two dimensions
for which a purely fermionic quasiparticle description of transport is badly
violated.

</DOC>
<DOC>
<DOCNO> 119724 </DOCNO>
A BeppoSAX and ROSAT view of the RCW86 supernova remnant


  We present a spectral analysis of the Northern and Southwestern rim of the
RCW86 X-ray shell, pointing out the remarkable differences between these two
parts of the same object. In the North, a single temperature Non Equilibrium of
Ionization emission model describes the data well, and the derived abundances
of O, Ne, Mg, Si, S, Ar and Fe are in agreement with expected metal depletion
behind a fast shock moving in the interstellar medium. If the initial explosion
energy was $\sim 10^{51}$ erg, the derived distance and age are
$1.18^{+0.17}_{-0.16}$ kpc and $1630^{+440}_{-360}$ yr, fully consistent with
the association to the historical supernova SN185. The X-ray emission from the
SW is described by a two-temperature emission model with kT$_{\rm h}=5.7$ keV
and kT$_{\rm l}=1.0$ keV. There is evidence of overabundant metals in the
high-temperature component, thus indicating the presence of ejecta. In this
case, a Type Ia SN is to be preferred over a more energetic Type II event,
which would imply a more distant and older remnant fully in its Sedov phase.

</DOC>
<DOC>
<DOCNO> 174490 </DOCNO>
Sideward flow of K+ mesons in Ru+Ru and Ni+Ni reactions near threshold


  Experimental data on K+ meson and proton sideward flow measured with the FOPI
detector at SIS/GSI in the reactions Ru+Ru at 1.69 AGeV and Ni+Ni at 1.93 AGeV
are presented. The K+ sideward flow is found to be anti-correlated (correlated)
with the one of protons at low (high) transverse momenta. When compared to the
predictions of a transport model, the data favour the existence of an in-medium
repulsive K+ nucleon potential.

</DOC>
<DOC>
<DOCNO> 83510 </DOCNO>
Performance and Scalability Models for a Hypergrowth e-Commerce Web Site


  The performance of successful Web-based e-commerce services has all the
allure of a roller-coaster ride: accelerated fiscal growth combined with the
ever-present danger of running out of server capacity. This chapter presents a
case study based on the author's own capacity planning engagement with one of
the hottest e-commerce Web sites in the world. Several spreadsheet techniques
are presented for forecasting both short-term and long-term trends in the
consumption of server capacity. Two new performance metrics are introduced for
site planning and procurement: the effective demand, and the doubling period.

</DOC>
<DOC>
<DOCNO> 85099 </DOCNO>
On the Observational Characteristics of Inhomogeneous Cosmologies:


  This thesis concerns the compatibility of inhomogeneous cosmologies with our
present understanding of the universe. It is a problem of some interest to find
the class of all relativistic cosmological models which are capable of
providing a reasonable `fit' to the universe. This thesis, in some respects, is
part of this process. We consider Stephani models, which are a generalisation
of the standard Friedmann-Lemaitre-Robertson-Walker (FLRW) models, which can be
thought of as FLRW models with acceleration and pressure gradients. Thus these
models generalise the `dust' assumption of standard cosmology.
  The crucial aspect of this work is the retention of the Copernican principle
-- an assumption regarded by many as crucial to cosmology. It states that we
are not at a special location in the universe. This is a vital aspect of the
original work in this thesis: consideration of an inhomogeneous model, while
retaining the Copernican principle has, as far as the author is aware, not been
considered in detail before.
  We start by generalising the Ehlers-Geren-Sachs Theorem to identify the class
of inhomogeneous spacetimes which allow an isotropic radiation field for all
observers in the spacetime. We then investigate observational and physical
aspects of these models from all observer locations. We conclude that there
exist spacetimes which conform to present observational constraints (especially
anisotropy constraints) for any location in the spacetime, while at the same
time being significantly inhomogeneous; ie, not `almost-FLRW'.

</DOC>
<DOC>
<DOCNO> 68910 </DOCNO>
CP odd anomalous interactions of Higgs boson in its production at Photon


  We discuss the potentialities of the study of CP-odd interactions of the
Higgs boson with photons via its production at gamma-gamma and e-gamma
colliders. Our treatment of H-gamma-gamma and H-Z-gamma anomalous interactions
includes a set of parameters, whose impact on physical observables has not been
considered before. We focus on two reactions - gamma+gamma-->H and e+gamma-->eH
- and introduce the polarization and/or azimuthal asymmetries that are
particularly sensitive to specific features of anomalies. We discuss the ways
of disentangling effects of physically different parameters of anomalies and
estimate what magnitude of CP violating phenomena can be seen in these
experiments.

</DOC>
<DOC>
<DOCNO> 13719 </DOCNO>
Ab initio calculation of resonant X-ray scattering in Manganites


  We study the origin of the resonant x-ray signal in manganites and generalize
the resonant cross-section to the band structure framework. With {\it ab
initio} LSDA and LSDA+U calculations we determine the resonant x-ray spectrum
of LaMnO$_3$. The calculated spectrum and azimuthal angle dependence at the Mn
$K$-edge reproduce the measured data without adjustable parameters. The
intensity of this signal is directly related to the orthorhombicity of the
lattice. We also predict a resonant x-ray signal at the La $L$-edge, caused by
the tilting of the MnO$_6$ octahedra. This shows that the resonant x-ray signal
in the hard x-ray regime can be understood in terms of the band structure of a
material and is sensitive to the fine details of crystal structure.

</DOC>
<DOC>
<DOCNO> 9762 </DOCNO>
Giant thermoemf in multiterminal superconductor/normal metal mesoscopic


  We considered a mesoscopic superconductor/normal metal (S/N) structure in
which the N reservoirs are maintained at different temperatures. It is shown
that in the absence of current between the N reservoirs a voltage difference
$V_{T}$ arises between the superconducting and normal conductors. The voltage
$V_{T}$ oscillates with increasing phase difference $\phi $ between the
superconductors, and its magnitude does not depend on the small parameter
$(T/\epsilon_{F}).$

</DOC>
<DOC>
<DOCNO> 121909 </DOCNO>
Estimation of relativistic accretion disk parameters from iron line


  The observed iron K-alpha fluorescence lines in Seyfert-1 galaxies provide
strong evidence for an accretion disk near a supermassive black hole as a
source of the emission. Here we present an analysis of the geometrical and
kinematic properties of the disk based on the extreme frequency shifts of a
line profile as determined by measurable flux in both the red and blue wings.
The edges of the line are insensitive to the distribution of the X-ray flux
over the disk, and hence provide a robust alternative to profile fitting of
disk parameters. Our approach yields new, strong bounds on the inclination
angle of the disk and the location of the emitting region. We apply our method
to interpret observational data from MCG-6-30-15 and find that the commonly
assumed inclination 30 deg for the accretion disk in MCG-6-30-15 is
inconsistent with the position of the blue edge of the line at a 3 sigma level.
A thick turbulent disk model or the presence of highly ionized iron may
reconcile the bounds on inclination from the line edges with the full line
profile fits based on simple, geometrically thin disk models. The bounds on the
innermost radius of disk emission indicate that the black hole in MCG-6-30-15
is rotating faster than 30 % of theoretical maximum. When applied to data from
NGC 4151, our method gives bounds on the inclination angle of the X-ray
emitting inner disk of 50\pm 10 deg, consistent with the presence of an
ionization cone grazing the disk as proposed by Pedlar et al. (1993). The
frequency extrema analysis also provides limits to the innermost disk radius in
another Seyfert-1 galaxy, NGC 3516.

</DOC>
<DOC>
<DOCNO> 99372 </DOCNO>
An inversion theorem in Fermi surface theory


  We prove a perturbative inversion theorem for the map between the interacting
and the noninteracting Fermi surface for a class of many fermion systems with
strictly convex Fermi surfaces and short-range interactions between the
fermions. This theorem gives a physical meaning to the counterterm function K
that we use in the renormalization of these models: K can be identified as that
part of the self--energy that causes the deformation of the Fermi surface when
the interaction is turned on.

</DOC>
<DOC>
<DOCNO> 169910 </DOCNO>
Theory of Decoherence-Free Fault-Tolerant Universal Quantum Computation


  Universal quantum computation on decoherence-free subspaces and subsystems
(DFSs) is examined with particular emphasis on using only physically relevant
interactions. A necessary and sufficient condition for the existence of
decoherence-free (noiseless) subsystems in the Markovian regime is derived here
for the first time. A stabilizer formalism for DFSs is then developed which
allows for the explicit understanding of these in their dual role as quantum
error correcting codes. Conditions for the existence of Hamiltonians whose
induced evolution always preserves a DFS are derived within this stabilizer
formalism. Two possible collective decoherence mechanisms arising from
permutation symmetries of the system-bath coupling are examined within this
framework. It is shown that in both cases universal quantum computation which
always preserves the DFS (*natural fault-tolerant computation*) can be
performed using only two-body interactions. This is in marked contrast to
standard error correcting codes, where all known constructions using one or
two-body interactions must leave the codespace during the on-time of the
fault-tolerant gates. A further consequence of our universality construction is
that a single exchange Hamiltonian can be used to perform universal quantum
computation on an encoded space whose asymptotic coding efficiency is unity.
The exchange Hamiltonian, which is naturally present in many quantum systems,
is thus *asymptotically universal*.

</DOC>
<DOC>
<DOCNO> 68341 </DOCNO>
Hadronic blazar models and correlated X-ray/TeV flares


  The hypothesis that AGN jets might be the sources of the ultra-high energy
cosmic rays has originally motivated the venture of TeV gamma ray astronomy.
Surprisingly, after the discovery of TeV emission from blazars the attention
has shifted to more traditional explanations which do not involve energetic
hadrons, and there is even common believe that a hadronic interpretation is
disfavored by observations. It is shown here that this is not the case, and
that the currently observed spectra and variability features of blazars can be
perfectly understood within hadronic blazar models. I also discuss how hadronic
models might be observationally distinguished from common leptonic models, and
point out some interesting aspects which could be relevant for the
understanding of the differences between blazar classes.

</DOC>
<DOC>
<DOCNO> 71517 </DOCNO>
Parton showers beyond the leading order: a factorization approach


  We discuss recent work on methods for incorporating nonleading QCD
corrections in parton shower algorithms.

</DOC>
<DOC>
<DOCNO> 122552 </DOCNO>
A High Resolution Spectroscopic Observation of CAL 83 with


  We present the first high resolution photospheric X-ray spectrum of a
Supersoft X-ray Source, the famous CAL~83 in the Large Magellanic Cloud. The
spectrum was obtained with the Reflection Grating Spectrometer on XMM-Newton
during the Calibration/Performance Verification phase of the observatory. The
spectrum covers the range 20-40 A at an approximately constant resolution of
0.05 A, and shows very significant, intricate detail, that is very sensitive to
the physical properties of the object. We present the results of an initial
investigation of the spectrum, from which we draw the conclusion that the
spectral structure is probably dominated by numerous absorption features due to
transitions in the L-shells of the mid-$Z$ elements and the M-shell of Fe, in
addition to a few strong K-shell features due to CNO.

</DOC>
<DOC>
<DOCNO> 9105 </DOCNO>
Concentration Dependen Sedimentation of Collidal Rods


  In the first part of this paper, an approximate theory is developed for the
leading order concentration dependence of the sedimentation coefficient for
rod-like colloids/polymers/macromolecules. To first order in volume fraction
$\phi$ of rods, the sedimentation coefficient is written as $1+\alpha \phi$.
For large aspect ratio L/D (L is the rod length, D it's thickness) $\alpha$ is
found to very like $\propto (\frac{L}{D})^2/\log (\frac{L}{D})$. This
theoretical prediction is compared to experimental results. In the second part,
experiments on {\it fd}-virus are described, both in the isotropic and nematic
phase. First order in concentration results for this very long and thin
(semi-flexible) rod are in agreement with the above theoretical prediction.
Sedimentation profiles for the nematic phase show two sedimentation fronts.
This result indicates that the nematic phase becomes unstable with the respect
to isotropic phase during sedimentation.

</DOC>
<DOC>
<DOCNO> 70529 </DOCNO>
Noncommutative QED and Anomalous Dipole Moments


  We study QED on noncommutative spaces, NCQED. In particular we present the
detailed calculation for the noncommutative electron-photon vertex and show
that the Ward identity is satisfied. We discuss that in the noncommutative case
moving electron will show {\it electric} dipole effects. In addition, we work
out the electric and magnetic dipole moments up to one loop level. For the
magnetic moment we show that noncommutative electron has an intrinsic (spin
independent) magnetic moment.

</DOC>
<DOC>
<DOCNO> 122457 </DOCNO>
Quark stars in Low-Mass X-ray Binaries: for and against


  It has been suggested that both X-ray bursters and millisecond radio pulsars
may be strange (quark) stars, rather than neutron stars. Confirming (or
rejecting) this suggestion may require knowing what role strong-field effects
of general relativity play in the accretion flow of the compact X-ray source in
low-mass X-ray binaries (LMXBs). We discuss the range of rotational and orbital
frequencies, and of masses expected in various models of strange stars, and
compare them with observational constraints, suggested by the observed
frequencies of kHz QPOs. We explain why future observations of transients (such
as SAX J~1808.4-3658) may be crucial to understanding the precise nature of the
accreting source. For flattened (e.g., rapidly rotating) distributions of
matter, an innermost (marginally) stable orbit may be present even if
relativistic effects are negligible. Depending on the stellar rotation rate,
the same value of orbital frequency in the innermost stable orbit (say, 0.9
kHz) can correspond to a star of mass equal to $2.4M_\odot$, $1.4M_\odot$,
$0.1M_\odot$, $0.01M_\odot$, or less.

</DOC>
<DOC>
<DOCNO> 119604 </DOCNO>
Dust Streamers in the Virgo Galaxy M86 from Ram Pressure Stripping of


  The giant elliptical galaxy M86 in Virgo has a ~28 kpc long dust trail inside
its optical halo that points toward the nucleated dwarf elliptical galaxy, VCC
882. The trail seems to be stripped material from the dwarf. Extinction
measurements suggest that the ratio of the total gas mass in the trail to the
blue luminosity of the dwarf is about unity, which is comparable to such ratios
in dwarf irregular galaxies. The ram pressure experienced by the dwarf galaxy
in the hot gaseous halo of M86 was comparable to the internal gravitational
binding energy density of the presumed former gas disk in VCC 882. Published
numerical models of this case are consistent with the overall trail-like
morphology observed here. Three concentrations in the trail may be evidence for
the predicted periodicity of the mass loss. The evaporation time of the trail
is comparable to the trail age obtained from the relative speed of the galaxies
and the trail length. Thus the trail could be continuously formed from stripped
replenished gas if the VCC 882 orbit is bound. However, the high gas mass and
the low expected replenishment rate suggest that this is only the first
stripping event. Implications for the origin of nucleated dwarf ellipticals are
briefly discussed.

</DOC>
<DOC>
<DOCNO> 13511 </DOCNO>
Electrical transport properties of RNiO3 (R= Pr, Nd, Sm) Epitaxial Thin


  Electrical transport properties of RNiO3 (R= Pr, Nd, Sm) thin films grown by
pulse laser deposition have been studied. RNiO3 films grow in (100) direction
on LaAlO3 (100) substrate. Unlike in polycrystalline solid, PrNiO3 film showed
metallic behavior. The first order metal to insulator transition observed in
polycrystalline solids is suppressed in RNiO3 films. The effect of lattice
strain in the films influensing the transport properties has been studied by
varying the thickness of PrNiO3 film on LaAlO3 and also by growing them on
SrTiO3 and sapphire substrates. Deviation in the transport properties is
explained due to the strain induced growth of the films. Further, we show that
the transport property of LaNiO3 film is also influenced by a similar strain
effect.

</DOC>
<DOC>
<DOCNO> 122936 </DOCNO>
Astrophysical factors:Zero energy vs. Most effective energy


  Effective astrophysical factors for non-resonant astrophysical nuclear
reaction are invariably calculated with respect to a zero energy limit. In the
present work that limit is shown to be very disadvantageous compared to the
more natural effective energy limit. The latter is used in order to modify the
thermonuclear reaction rate formula so that it takes into account both plasma
and laboratory screening effects.

</DOC>
<DOC>
<DOCNO> 10261 </DOCNO>
Weakly Nonextensive Thermostatistics and the Ising Model with


  We introduce a nonextensive entropic measure $S_{\chi}$ that grows like
$N^{\chi}$, where $N$ is the size of the system under consideration. This kind
of nonextensivity arises in a natural way in some $N$-body systems endowed with
long-range interactions described by $r^{-\alpha}$ interparticle potentials.
The power law (weakly nonextensive) behavior exhibited by $S_{\chi}$ is
intermediate between (1) the linear (extensive) regime characterizing the
standard Boltzmann-Gibbs entropy and the (2) the exponential law (strongly
nonextensive) behavior associated with the Tsallis generalized $q$-entropies.
The functional $S_{\chi} $ is parametrized by the real number $\chi \in[1,2]$
in such a way that the standard logarithmic entropy is recovered when $\chi=1$
>. We study the mathematical properties of the new entropy, showing that the
basic requirements for a well behaved entropy functional are verified, i.e.,
$S_{\chi}$ possesses the usual properties of positivity, equiprobability,
concavity and irreversibility and verifies Khinchin axioms except the one
related to additivity since $S_{\chi}$ is nonextensive. For $1<\chi<2$, the
entropy $S_{\chi}$ becomes superadditive in the thermodynamic limit. The
present formalism is illustrated by a numerical study of the thermodynamic
scaling laws of a ferromagnetic Ising model with long-range interactions.

</DOC>
<DOC>
<DOCNO> 101763 </DOCNO>
A Poisson Bracket on Multisymplectic Phase Space


  A new Poisson bracket for Hamiltonian forms on the full multisymplectic phase
space is defined. At least for forms of degree n-1, where n is the dimension of
space-time, Jacobi's identity is fulfilled.

</DOC>
<DOC>
<DOCNO> 39890 </DOCNO>
Radio-Frequency Measurements of Coherent Transition and Cherenkov


  We report on measurements of 11-18 cm wavelength radio emission from
interactions of 15.2 MeV pulsed electron bunches at the Argonne Wakefield
Accelerator. The electrons were observed both in a configuration where they
produced primarily transition radiation from an aluminum foil, and in a
configuration designed for the electrons to produce Cherenkov radiation in a
silica sand target. Our aim was to emulate the large electron excess expected
to develop during an electromagnetic cascade initiated by an ultra high-energy
particle. Such charge asymmetries are predicted to produce strong coherent
radio pulses, which are the basis for several experiments to detect high-energy
neutrinos from the showers they induce in Antarctic ice and in the lunar
regolith. We detected coherent emission which we attribute both to transition
and possibly Cherenkov radiation at different levels depending on the
experimental conditions. We discuss implications for experiments relying on
radio emission for detection of electromagnetic cascades produced by ultra
high-energy neutrinos.

</DOC>
<DOC>
<DOCNO> 117308 </DOCNO>
Solution of Poisson's equation for finite systems using plane wave


  Reciprocal space methods for solving Poisson's equation for finite charge
distributions are investigated. Improvements to previous proposals are
presented, and their performance is compared in the context of a real-space
density functional theory code. Two basic methodologies are followed:
calculation of correction terms, and imposition of a cut-off to the Coulomb
potential. We conclude that these methods can be safely applied to finite or
aperiodic systems with a reasonable control of speed and accuracy.

</DOC>
<DOC>
<DOCNO> 70793 </DOCNO>
Quasi-multi-Regge Processes with a Quark Exchange in the t-channel


  The QCD amplitudes for particle's production in the quasi-multi-Regge
kinematics with a quark exchange in crossing channels are calculated in the
Born approximation. In particular they are needed to find next-to-leading
corrections to the quark Regge trajectory and to the integral kernel of the
Bethe-Salpeter equation for the t-channel partial wave with fermion quantum
numbers and a negative signature. The gauge-invariant action for the
interaction of the reggeized quarks and gluons with the usual particles is
constructed.

</DOC>
<DOC>
<DOCNO> 13576 </DOCNO>
Note on the Spin-Spin Relaxation Time in High-Tc Cuprate Superconductors


  Recent experiments on the spin-spin relaxation time in high-Tc cuprate
superconductors are discussed on the basis of the BCS-RPA theory.

</DOC>
<DOC>
<DOCNO> 169989 </DOCNO>
Transient interference of transmission and incidence


  Due to a transient quantum interference during a wavepacket collision with a
potential barrier, a particular momentum, that depends on the potential
parameters but is close to the initial average momentum, becomes suppressed.
The hole left pushes the momentum distribution outwards leading to a
significant constructive enhancement of lower and higher momenta. This is
explained in the momentum complex-plane language in terms of a saddle point and
two contiguous ``structural'' poles, which are not associated with resonances
but with incident and transmitted components of the wavefunction.

</DOC>
<DOC>
<DOCNO> 69669 </DOCNO>
Strongly-interacting fermions from a higher-dimensional unified gauge


  The method of coset-space dimensional reduction is employed in order to
proceed from a gauged E_8 * E_8' unified theory defined in 10 dimensions to 4
dimensions. The resulting theory comprises the Standard Model along with a
strongly-interacting fermion sector which breaks the electroweak symmetry
dynamically at the right scale.

</DOC>
<DOC>
<DOCNO> 11866 </DOCNO>
Secure and linear cryptosystems using error-correcting codes


  A public-key cryptosystem, digital signature and authentication procedures
based on a Gallager-type parity-check error-correcting code are presented. The
complexity of the encryption and the decryption processes scale linearly with
the size of the plaintext Alice sends to Bob. The public-key is pre-corrupted
by Bob, whereas a private-noise added by Alice to a given fraction of the
ciphertext of each encrypted plaintext serves to increase the secure channel
and is the cornerstone for digital signatures and authentication. Various
scenarios are discussed including the possible actions of the opponent Oscar as
an eavesdropper or as a disruptor.

</DOC>
<DOC>
<DOCNO> 11063 </DOCNO>
Electron Glass in Ultrathin Granular Al Films at Low Temperatures


  Quench-condensed granular Al films, with normal-state sheet resistance close
to 10 k$\Omega/\Box$, display strong hysteresis and ultraslow, non-exponential
relaxation in the resistance when temperature is varied below 300 mK. The
hysteresis is nonlinear and can be suppressed by a dc bias voltage. The
relaxation time does not obey the Arrhenius form, indicating the existence of a
broad distribution of low energy barriers. Furthermore, large resistance
fluctuations, having a 1/f-type power spectrum with a low-frequency cut-off,
are observed at low temperatures. With decreasing temperature, the amplitude of
the fluctuation increases and the cut-off frequency decreases. These
observations combine to provide a coherent picture that there exists a new
glassy electron state in ultrathin granular Al films, with a growing
correlation length at low temperatures.

</DOC>
<DOC>
<DOCNO> 118276 </DOCNO>
Chandra uncovers a hidden Low-Luminosity AGN in the radio galaxy Hydra~A


  We report the detection with Chandra of a Low-Luminosity AGN (LLAGN) in the
Low Ionization Emission Line Region (LINER) hosted by Hydra A, a nearby
(z=0.0537) powerful FRI radio galaxy with complex radio and optical morphology.
In a 20 ks ACIS-S exposure during the calibration phase of the instrument, a
point source is detected at energies $\grtsim$ 2 keV at the position of the
compact radio core, embedded in diffuse thermal X-ray emission ($kT \sim 1$
keV) at softer energies. The spectrum of the point source is well fitted by a
heavily absorbed power law with intrinsic column density N$_H^{int} \sim 3
\times 10^{22}$ \nh and photon index $\Gamma \sim 1.7$. The intrinsic
(absorption-corrected) luminosity is $L_{2-10 keV} \sim 1.3 \times 10^{42}$
\lum. These results provide strong evidence that an obscured AGN is present in
the nuclear region of Hydra~A. We infer that the optical/UV emission of the AGN
is mostly hidden by the heavy intrinsic reddening. In order to balance the
photon budget of the nebula, we must either postulate that the ionizing
spectrum includes a UV bump or invoke and additional power source (shocks in
the cooling flow or interaction with the radio jets). Using an indirect
estimate of the black hole mass and the X-ray luminosity, we infer that the
accretion rate is low, suggesting that the accretion flow is advection
dominated. Finally, our results support current unification schemes for
radio-loud sources, in particular the presence of the putative molecular torus
in FR~Is. These observations underscore the power of the X-rays and of \chandra
in the quest for black holes.

</DOC>
<DOC>
<DOCNO> 169807 </DOCNO>
A quantum computer only needs one universe


  I give an informal discussion of the nature of quantum computation, arguing
that, in terms of the amount of information manipulated in a given time,
quantum and classical computation are equally efficient. Quantum superposition
does not permit quantum computers to "perform many computations simultaneously"
except in a highly qualified and to some extent misleading sense. Quantum
computation is therefore not well described by interpretations of quantum
mechanics which invoke the concept of vast numbers of parallel universes.
Rather, entanglement makes available types of computation process which, while
not exponentially larger than classical ones, are unavailable to classical
systems.

</DOC>
<DOC>
<DOCNO> 99459 </DOCNO>
The Module of Logarithmic p-forms of a Locally Free Arrangement


  For an essential, central hyperplane arrangement A in V=k^{n+1}, we show that
\Omega^1(A) (the module of logarithmic one forms with poles along A) gives rise
to a locally free sheaf on P^n if and only if for all X in L_A with rank X<dim
V, the module \Omega^1(A_X) is free. Our main result is that in this case the
Poicare polynomial of A is essentially the Chern polynomial. The proof is based
on a result of Solomon and Terao and on a formula we give for the Chern
polynomial of a bundle E on P^n in terms of the Hilbert series of \oplus_m
H^0(\wedge^iE(m)). If \Omega^1(A)has projective dimension one and is locally
free, we give a minimal free resolution for \Omega^p, and show that
\wedge^p(\Omega^1(A))\iso\Omega^p(A), generalizing results of Rose and Terao on
generic arrangements.

</DOC>
<DOC>
<DOCNO> 70510 </DOCNO>
Some Recent Results from the Complete Theory of SUSY without R-parity


  We review an efficient formulation of the complete theory of supersymmetry
without R-parity, where all the admissible R-parity violating terms
incorporated. Some interesting recent results will be discussed, including
newly identified 1-loop contributions to neutrino masses and electric dipole
moments of neutron and electron, resulted from R-parity violating LR squark and
slepton mixings.

</DOC>
<DOC>
<DOCNO> 150425 </DOCNO>
Frobenius-Schur Indicators, the Klein-bottle Amplitude, and the


  The "orbifold covariance principle", or OCP for short, is presented to
support a conjecture of Pradisi, Sagnotti and Stanev on the expression of the
Klein- bottle amplitude.

</DOC>
<DOC>
<DOCNO> 119015 </DOCNO>
Kinematics and morphology of ionized gas in Hickson Compact Group 18


  We present new observations of $H\alpha $ emission in the Hickson Compact
Group 18 (HCG 18) obtained with a scanning Fabry-Perot interferometer. The
velocity field does not show motions of individual group members but, instead,
a complex common velocity field for the whole group. The gas distribution is
very asymmetric with clumps of maximum intensity coinciding with the optically
brightest knots. Comparing $H\alpha $ and HI data we conclude that HCG 18 is
not a compact group but instead a large irregular galaxy with several clumps of
star formation.

</DOC>
<DOC>
<DOCNO> 13764 </DOCNO>
Domain Coarsening in Electroconvection


  We report on experimental measurements of the growth of regular domains
evolving from an irregular pattern in electroconvection. The late-time growth
of the domains is consistent with the size of the domains scaling as $t^n$. We
use two isotropic measurements of the domain size: the structure factor and the
domain wall length. Measurements using the structure factor are consistent with
$t^{1/5}$ growth. Measurements using the domain wall length are consistent with
$t^{1/4}$ growth. One source of this discrepancy is the fact that the
distribution of local wavenumbers is approximately independent of the domain
size. In addition, we measure the anisotropy of the growing domains.

</DOC>
<DOC>
<DOCNO> 69391 </DOCNO>
Why odd-space and odd-time dimensions in even-dimesional spaces?


  We are answering the question why 4-dimensional space has the metric 1+3 by
making a general argument from a certain type of equations of motion linear in
momentum for any spin (except spin zero) in any even dimension d. All known
free equations for non-zero spin for massless fields belong to this type of
equations. Requiring Hermiticity(This is a generalization of an earlier work
which shows that without assuming the Lorentz invariance -which in the present
work is assumed- the Weyl equation follows using Hermiticity.) of the equations
of motion operator as well as irreducibility with respect to the Lorentz group
representation, we prove that only metrics with the signature corresponding to
q time + (d - q) space dimensions with q being odd exist. Correspondingly, in
four dimensional space, Nature could only make the realization of 1+3
dimensional space.

</DOC>
<DOC>
<DOCNO> 80699 </DOCNO>
Quantum Spin Formulation of the Principal Chiral Model


  We formulate the two-dimensional principal chiral model as a quantum spin
model, replacing the classical fields by quantum operators acting in a Hilbert
space, and introducing an additional, Euclidean time dimension. Using coherent
state path integral techniques, we show that in the limit in which a large
representation is chosen for the operators, the low energy excitations of the
model describe a principal chiral model in three dimensions. By dimensional
reduction, the two-dimensional principal chiral model of classical fields is
recovered.

</DOC>
<DOC>
<DOCNO> 69521 </DOCNO>
CP and T violation in long baseline experiments with low energy neutrino


  Stimulated by the idea of PRISM, a very high intensity muon ring with rather
low energy, we consider possibilities of observing CP-violation effects in
neutrino oscillation experiments. Destructive sum of matter effect and
CP-violation effect can be avoided with use of initial $\nu_{\rm e}$ beam. We
finally show that the experiment with (a few) $\times$ 100 MeV of neutrino
energy and (a few) $\times$ 100 km of baseline length, which is considered in
this paper, is particularly suitable for a search of CP violation in view of
3-generation nature of CP violation.

</DOC>
<DOC>
<DOCNO> 99677 </DOCNO>
Special Kaehler geometry


  The geometry that is defined by the scalars in couplings of Einstein-Maxwell
theories in N=2 supergravity in 4 dimensions is denoted as special Kaehler
geometry. There are several equivalent definitions, the most elegant ones
involve the symplectic duality group. The original construction used conformal
symmetry, which immediately clarifies the symplectic structure and provides a
way to make connections to quaternionic geometry and Sasakian manifolds.

</DOC>
<DOC>
<DOCNO> 169652 </DOCNO>
New strategy for suppressing decoherence in quantum computation


  Controlable strong interaction of the qubit's bath with an external system
(i.e. with the bath's environment) allows for choosing the conditions under
which the decoherence of the qubit's states can be substantially decreased (in
a certain limit: completely avoided). By "substantially decreased" we mean that
the correlations which involve the bath's states prove negligible, while the
correlations between the qubit's and the environment's states can be made
ineffective during a comparatively long time interval. So, effectively, one may
choose the conditions under which, for sufficiently long time interval, the
initial state of "qubit + bath" remains unchanged, thus removing any kind of
the errors. The method has been successfully employed in the (simplified) model
of the solid-state-nuclear quantum computer (proposed by Kane).

</DOC>
<DOC>
<DOCNO> 84979 </DOCNO>
Exact Solutions with w - modes


  An explicit necessary condition for the occurrence of resonance scattering of
axial gravitational waves, along with the internal trapping of null geodesics,
is proposed for static spherically symmetric perfect fluid solutions to
Einstein's equations. Some exact inhomogeneous solutions which exhibit this
trapping are given with special attention to boundary conditions and the
physical acceptability of the space times. In terms of the tenuity ($\alpha =
R/M$ at the boundary) all the examples given lie in the narrow range $2.8 <
\alpha < 2.9$. The tenuity can be raised to more interesting values by the
addition of an envelope without altering the trapping.

</DOC>
<DOC>
<DOCNO> 178737 </DOCNO>
Distorted wave impulse approximation analysis for spin observables in


  We present a formalism of distorted wave impulse approximation (DWIA) for
analyzing spin observables in nucleon inelastic and charge exchange reactions
leading to the continuum. It utilizes response functions calculated by the
continuum random phase approximation (RPA), which include the effective mass,
the spreading widths and the \Delta degrees of freedom. The Fermi motion is
treated by the optimal factorization, and the non-locality of the
nucleon-nucleon t-matrix by an averaged reaction plane approximation. By using
the formalism we calculated the spin-longitudinal and the spin-transverse cross
sections, ID_q and ID_p, of 12C, 40Ca (\vec{p},\vec{n}) at 494 and 346 MeV. The
calculation reasonably reproduced the observed ID_q, which is consistent with
the predicted enhancement of the spin-longitudinal response function R_L.
However, the observed ID_p is much larger than the calculated one, which was
consistent with neither the predicted quenching nor the spin-transverse
response function R_T obtained by the (e,e') scattering. The Landau-Migdal
parameter g'_N\Delta for the N\Delta transition interaction and the effective
mass at the nuclear center m^*(r=0) are treated as adjustable parameters. The
present analysis indicates that the smaller g'_{N\Delta}(\approx 0.3) and
m^*(0) \approx 0.7 m are preferable. We also investigate the validity of the
plane wave impulse approximation (PWIA) with the effective nucleon number
approximation for the absorption, by means of which R_L and R_T have
conventionally been extracted.

</DOC>
<DOC>
<DOCNO> 13051 </DOCNO>
Identification of Electron Donor States in N-doped Carbon Nanotubes


  Nitrogen doped carbon nanotubes have been synthesized using pyrolysis and
characterized by Scanning Tunneling Spectroscopy and transmission electron
microscopy. The doped nanotubes are all metallic and exhibit strong electron
donor states near the Fermi level. Using tight-binding and ab initio
calculations, we observe that pyridine-like N structures are responsible for
the metallic behavior and the prominent features near the Fermi level. These
electron rich structures are the first example of n-type nanotubes, which could
pave the way to real molecular hetero-junction devices.

</DOC>
<DOC>
<DOCNO> 117403 </DOCNO>
Can DNA bases be produced during molecular cloud collapse?


  Using a reasonably large chemical reaction network consisting of 421 species,
we show that along with normal chemical evolution of molecular cloud during
collapse and star formation, significant amount of adenine, a DNA base, may be
produced after an evolution of 10^{6-7} years. This findings may shed light on
whether life on earth had to begin from scratch or these molecules could have
contaminated the earth from the beginning.

</DOC>
<DOC>
<DOCNO> 169627 </DOCNO>
A Heuristic Approach to the Relativistic Angular Momentum


  The relativistic angular momentum is introduced as an extension of the
non-relativistic analysis of allowed states in the phase space for a quantum
particle. The paper shows the conceptual basis of the approach. An interesting
feature of the present point of view is that the indistinguishability of
identical particles and the Pauli principle are found as corollaries.

</DOC>
<DOC>
<DOCNO> 117025 </DOCNO>
A simple unbreakable code


  A simple unbreakable cipher system is presented which uses the concept of
"pseudo-bits" that has never been used in either classical or quantum
cryptography.

</DOC>
<DOC>
<DOCNO> 70940 </DOCNO>
Neutron unpolarized structure function F_2^n(x) from deep inelastic


  The possibility to safely extract the neutron deep inelastic structure
function $F_2^n(x)$ in the range $0 \le x \le 0.9$ from joint measurements of
deep inelastic structure functions of $^{3}He$ and $^{3}H$ is demonstrated.
While the nuclear structure effects are relevant, the model dependence in this
extraction linked to the $N-N$ interaction is shown to be weak.

</DOC>
<DOC>
<DOCNO> 102331 </DOCNO>
Arrangements, Milnor Fibers and Polar Curves


  We describe a new relation between the topology of hyperplane arrangements,
Milnor fibers and global polar curves, via the affine Lefschetz theory
developped by A. N\'emethi. In particular, we improve some results due to Orlik
and Terao (see Math. Ann. 301(1995)) and complete/clarify a proof by Randell
concerning the minimality of hyperplane arrangements (see math.AT/0011101).

</DOC>
<DOC>
<DOCNO> 83061 </DOCNO>
Fractal Symbolic Analysis


  Restructuring compilers use dependence analysis to prove that the meaning of
a program is not changed by a transformation. A well-known limitation of
dependence analysis is that it examines only the memory locations read and
written by a statement, and does not assume any particular interpretation for
the operations in that statement. Exploiting the semantics of these operations
enables a wider set of transformations to be used, and is critical for
optimizing important codes such as LU factorization with pivoting.
  Symbolic execution of programs enables the exploitation of such semantic
properties, but it is intractable for all but the simplest programs. In this
paper, we propose a new form of symbolic analysis for use in restructuring
compilers. Fractal symbolic analysis compares a program and its transformed
version by repeatedly simplifying these programs until symbolic analysis
becomes tractable, ensuring that equality of simplified programs is sufficient
to guarantee equality of the original programs. We present a prototype
implementation of fractal symbolic analysis, and show how it can be used to
optimize the cache performance of LU factorization with pivoting.

</DOC>
<DOC>
<DOCNO> 120407 </DOCNO>
The ages of very cool hydrogen-rich white dwarfs


  The evolution of white dwarfs is essentially a cooling process that depends
primarily on the energy stored in their degenerate cores and on the
transparency of their envelopes. In this paper we compute accurate cooling
sequences for carbon-oxygen white dwarfs with hydrogen dominated atmospheres
for the full range of masses of interest. For this purpose we use the most
accurate available physical inputs for both the equation of state and opacities
of the envelope and for the thermodynamic quantities of the degenerate core. We
also investigate the role of the latent heat in the computed cooling sequences.
We present separately cooling sequences in which the effects of phase
separation of the carbon-oxygen binary mixture upon crystallization have been
neglected, and the delay introduced in the cooling times when this mechanism is
properly taken into account, in order to compare our results with other
published cooling sequences which do not include a treatment of this
phenomenon. We find that the cooling ages of very cool white dwarfs with pure
hydrogen atmospheres have been systematically underestimated by roughly 1.5 Gyr
at log(L/Lo)=-4.5 for an otherwise typical 0.6 Mo white dwarf, when phase
separation is neglected. If phase separation of the binary mixture is included
then the cooling ages are further increased by roughly 10%. Cooling tracks and
cooling isochrones in several color-magnitude diagrams are presented as well.

</DOC>
<DOC>
<DOCNO> 9840 </DOCNO>
Onset of dielectric modes at 110K and 60K due to local lattice


  We report the observation of two dielectric transitions at 110K and 60K in
the microwave response of non-superconducting YBa_{2}Cu_{3}O_{6.0} crystals.
The transitions are characterized by a change in polarizability and presence of
loss peaks, associated with overdamped dielectric modes. An explanation is
presented in terms of changes in polarizability of the apical O atoms in the
Ba-O layer, affected by lattice softening at 110K, due to change in buckling of
the Cu-O layer. The onset of another mode at 60K strongly suggests an
additional local lattice change at this temperature. Thus microwave dielectric
measurements are sensitive indicators of lattice softening which may be
relevant to superconductivity.

</DOC>
<DOC>
<DOCNO> 170741 </DOCNO>
Manipulating decay rates by entanglement and the Zeno effect


  We analyse a class of quantum dynamical processes which may lead to the
hindering of the decay of a non-stationary state through appropriate
entanglement with an additional two-level system. In this case the process can
be considered as a module whose iteration is related to dynamical
implementations of the so called quantum Zeno effect.

</DOC>
<DOC>
<DOCNO> 121094 </DOCNO>
The complete S5 polar cap sample: en route to phase-delay global


  We report on the present status of our S5 polar cap phase-connected
astrometry program. We observe 13 radio sources in the northernmost 20deg of
the sky at the wavelengths of 3.6cm and 2cm, and we plan to extend the program
to 0.7cm. We phase-connect jointly all our data successfully. We image the
radio sources and some of them show morphological changes, in which astrometric
registration is needed to determine the kinematics of the source components. We
aim at unprecedented astrometric accuracy and at a check of the jet standard
model at the 5-10 microarcsec/yr level.

</DOC>
<DOC>
<DOCNO> 13643 </DOCNO>
Magnetic and orbital ordering in cuprates and manganites


  The mechanisms of magnetic and orbital interactions due to double exchange
(DE) and superexchange (SE) in transition metal oxides with degenerate e_g
orbitals are presented. Specifically, we study the effective spin-orbital
models derived for the d^9 ions as in KCuF_3, and for the d^4 ions as in
LaMnO_3, for spins S=1/2 and S=2, respectively. Such models are characterized
by three types of elementary excitations: spin waves, orbital waves, and
spin-and-orbital waves. The SE interactions between Cu^{2+} (d^9) ions are
inherently frustrated, which leads to a new mechanism of spin liquid which
operates in three dimensions. The SE between Mn^{3+} (d^4) ions explains the
A-type antiferromagnetic order in LaMnO_3 which coexists with the orbital
order. In contrast, the ferromagnetic metallic phase and isotropic spin waves
observed in doped manganites are explained by DE for degenerate e_g orbitals.
It is shown that although a hole does not couple to spin excitations in
ferromagnetic planes of LaMnO_3, the orbital excitations change the energy
scale for the coherent hole propagation and cause a large redistribution of
spectral weight. Finally, we point out some open problems in the present
understanding of doped manganites.

</DOC>
<DOC>
<DOCNO> 151813 </DOCNO>
Reflection factors and a two-parameter family of boundary bound states


  The investigation of boundary breather states of the sinh-Gordon model
restricted to a half-line is revisited. Properties of the classical boundary
breathers for the two-parameter family of integrable boundary conditions are
reviewed and extended. The energy spectrum of the quantized boundary states is
computed, firstly by using a bootstrap technique and, subsequently using a WKB
approximation. Requiring that the two descriptions of the spectrum agree with
one another allows a determination of the relationship between the boundary
parameters, the bulk coupling constant, and the two parameters appearing in the
reflection factor describing the scattering of the sinh-Gordon particle from
the boundary. These calculations had been performed previously for the case in
which the boundary conditions preserve the bulk $Z_2$ symmetry of the model.
The significantly more difficult case of general boundary conditions which
violate the bulk symmetry is treated in this article. The results clarify the
weak-strong coupling duality of the sinh-Gordon model with integrable boundary
conditions.

</DOC>
<DOC>
<DOCNO> 101412 </DOCNO>
Universal Spectra and Tijdeman's Conjecture on Factorization of Cyclic


  A spectral set in R^n is a set X of finite Lebesgue measure such that L^2(X)
has an orthogonal basis of exponentials. It is conjectured that every spectral
set tiles R^n by translations. A set of translations T has a universal spectrum
if every set that that tiles by translations by T has this spectrum. A recent
result proved that many periodic tiling sets have universal spectra, using
results from factorizations of abelian groups, for groups for which a strong
form of a conjecture of Tijdeman is valid. This paper shows Tijdeman's
conjecture does not hold for the cyclic group of order 900. It formulates a new
sufficient conjecture for a periodic tiling set to have a universal spectrum,
and uses it to show that the tiling sets for the counterexample above do have
universal spectra.

</DOC>
<DOC>
<DOCNO> 100588 </DOCNO>
Absolute non-Archimedean polyhedral expansions of ultrauniform spaces


  This work is devoted to the investigation of the problem about inverse
mapping systems expansions of ultrauniform spaces $X$ using polyhedra over
non-Archimedean locally compact fields $\bf L$. Theorems about expansions of
complete ultrametric and ultrauniform spaces are proved. Absolute polyhedral
expansions and inverse mapping systems of expansions for non-complete spaces
are investigated. This article also contains results about a relation of $dim
(X)$ and dimensions of polyhedra over $\bf L$.

</DOC>
<DOC>
<DOCNO> 100761 </DOCNO>
Wheeling: A diagrammatic analogue of the Duflo isomorphism


  We construct and prove a diagrammatic version of the Duflo isomorphism
between the invariant subalgebra of the symmetric algebra of a Lie algebra and
the center of the universal enveloping algebra. This version implies the
original for metrized Lie algebras (Lie algebras with an invariant
non-degenerate bilinear form). As an application of this isomorphism, we will
compute the Kontsevich integral of the unknot and the Hopf link to all orders.
 At the core of the proof, we use an elementary property of the Hopf link which
can be summarized by the equation ``1+1=2'' in abacus arithmetic: doubling one
component of the Hopf link is equivalent to taking the connected sum of two
Hopf links. This property of the Hopf link turns out, when suitably
interpreted, to be exactly the property required for the Duflo map to be
multiplicative.
 To compute the Kontsevich integral of the unknot, we use a property of the
unknot that can be summarized by ``n * 0 = 0'': the n-fold connected cabling of
the unknot is again an unknot.

</DOC>
<DOC>
<DOCNO> 120367 </DOCNO>
X-ray Source Populations in the Region of the Open Clusters NGC 6633 and


  Using deep exposures (~10^5 s) with the ROSAT HRI, we have performed
flux-limited surveys for X-ray sources in the vicinity of the Hyades-age open
stellar clusters NGC 6633 and IC 4756, detecting 31 and 13 sources
respectively. Our primary aim is to search for so-far unrecognised cluster
members. We propose identifications or classifications (cluster member, field
star, extragalactic field object) for the X-ray sources, based on published
membership lists, and on X-ray:optical flux ratios and optical
colour--magnitude diagrams. Results of simulating the expected X-ray-emitting
source populations are compared with the ROSAT measurements and with the
expected capabilities of the XMM mission. The simulations provide a novel
method of comparing the activity levels of NGC 6633 and IC 4756 with that of
the Hyades. The measurements and simulations confirm that cluster members are
the major class of X-ray emitter in these fields at flux levels f_x >
10^{-14}/erg/cm^2/s (0.1--2.4 keV), contributing ~40 per cent of the total
X-ray sources. We find 6 possible new members in NGC 6633, and 4 candidates in
IC 4756; all require further observation to establish membership probability.

</DOC>
<DOC>
<DOCNO> 151667 </DOCNO>
Chiral Superfields in IIB Supergravity


  The field strength superfield of IIB supergravity on $AdS_5\xz S^5$ is
expanded in harmonics on $S^5$ with coefficients which are $D=5, N=8$ chiral
superfields. On the boundary of $AdS_5$ these superfields map to $D=4,N=4$
chiral superfields and both sets of superfields obey additional fourth-order
constraints. The constraints on the $D=4,N=4$ chiral fields are solved using
harmonic superspace in terms of prepotential superfields which couple in a
natural way to composite operator multiplets of the boundary $N=4,D=4$
superconformal field theory.

</DOC>
<DOC>
<DOCNO> 13050 </DOCNO>
The relationship between fragility, configurational entropy and the


  Glass is a microscopically disordered, solid form of matter that results when
a fluid is cooled or compressed in such a fashion that it does not crystallise.
Almost all types of materials are capable of glass formation -- polymers, metal
alloys, and molten salts, to name a few. Given such diversity, organising
principles which systematise data concerning glass formation are invaluable.
One such principle is the classification of glass formers according to their
fragility\cite{fragility}. Fragility measures the rapidity with which a
liquid's properties such as viscosity change as the glassy state is approached.
Although the relationship between features of the energy landscape of a glass
former, its configurational entropy and fragility have been analysed previously
(e. g.,\cite{speedyfr}), an understanding of the origins of fragility in these
features is far from being well established. Results for a model liquid, whose
fragility depends on its bulk density, are presented in this letter. Analysis
of the relationship between fragility and quantitative measures of the energy
landscape (the complicated dependence of energy on configuration) reveal that
the fragility depends on changes in the vibrational properties of individual
energy basins, in addition to the total number of such basins present, and
their spread in energy. A thermodynamic expression for fragility is derived,
which is in quantitative agreement with {\it kinetic} fragilities obtained from
the liquid's diffusivity.

</DOC>
<DOC>
<DOCNO> 13862 </DOCNO>
Structural and Electronic Properties of a Carbon Nanotorus: Effects of


  The bending of a carbon nanotube is studied by considering the structural
evolution of a carbon nanotorus from elastic deformation to the onset of the
kinks and eventually to the collapse of the walls of the nanotorus. The changes
in the electronic properties due to {\it non-local} deformation are contrasted
with those due to {\it local} deformation to bring out the subtle issue
underlying the reason why there is only a relatively small reduction in the
electrical conductance in the former case even at large bending angles while
there is a dramatic reduction in the conductance in the latter case at
relatively small bending angles.

</DOC>
<DOC>
<DOCNO> 122776 </DOCNO>
Extreme Ultraviolet Emission from Abell 4059


  We present the results of a search for Extreme Ultraviolet emission in A4059,
a cluster with an X-ray emitting cluster gas. Our analysis of Extreme
Ultraviolet Explorer (EUVE) Deep Survey observations of this cluster shows that
it is associated with diffuse EUV emission. Outside the central 2 arcmin radius
the entire EUV emission detected is explained by the low energy tail of the
X-ray emitting gas. Within the central 2 arcmin region of the cluster we find a
deficit of EUV emission compared to that expected from the X-ray gas. This flux
deficit is discussed in the context of the cluster's cooling flow. The results
derived for A4059 are compared to EUVE results obtained for other clusters such
as Coma, Virgo, A1795, and A2199. As part of the study we have carried out a
detailed investigation of the stability of the EUVE Deep Survey detector
background. Based on long integrations of blank sky over 27 months we disprove
claims of substantial time dependent changes in the detector background by R.
Lieu and coworkers. We also show, contrary to the claim of R. Lieu and
coworkers, that the images obtained with the detector are independent of the
pulse height threshold of the detector over a substantial range of threshold
settings.

</DOC>
<DOC>
<DOCNO> 123278 </DOCNO>
Chandra studies of star forming regions


  When observed with sufficiently high spatial resolution and sensitivity, star
formation regions are unusually complex X-ray sources. Low-mass protostars and
T Tauri stars, Herbig Ae/Be stars, OB and Wolf-Rayet stars are seen at levels
$28 \leq \log L_x \leq 34$ erg/s. High-amplitude variability from magnetic
reconnection flares are often present. From past star formation episodes,
supernova remnants and X-ray binary systems may dominate the emission on large
scales. Astrophysically, ionization of molecular material from yount stellar
X-rays which may have important consequences for circumstellar disk evolution,
bipolar flow ejection and star formation.
  We report here early results from Chandra X-ray Observatory studies of a wide
range of star forming regions using the ACIS camera. They include portions of
the nearby Ophiuchus and Perseus clouds, the Orion Nebula Cluster (ONC) and
elsewhere in the Orion giant molecular clouds, molecular clouds and star
clusters around the Galactic Center, the 30 Doradus region of the LMC, and the
prototype starburst galaxy M 82.

</DOC>
<DOC>
<DOCNO> 151859 </DOCNO>
Gauge models in modified triplectic quantization


  We apply the modified triplectic formalism for quantizing several popular
gauge models - non-abelian antisymmetric tensor field model, W2-gravity and
two-dimensional gravity with dynamical torsion. The explicit solutions are
obtained for the generating equations of the quantum action and the
gauge-fixing functional. Using these solutions we construct the vacuum
functional and obtain the corresponding transformations of the extended BRST
symmetry.

</DOC>
<DOC>
<DOCNO> 101362 </DOCNO>
Constraints in polysymplectic (covariant) Hamiltonian formalism


  In the framework of polysymplectic Hamiltonian formalism, degenerate
Lagrangian field systems are described as multi-Hamiltonian systems with
Lagrangian constraints. The physically relevant case of degenerate quadratic
Lagrangians is analized in detail, and the Koszul--Tate resolution of
Lagrangian constraints is constructed in an explicit form. The particular case
of Hamiltonian mechanics with time-dependent constraints is studied.

</DOC>
<DOC>
<DOCNO> 71841 </DOCNO>
Real Time Nonequilibrium Dynamics of Quantum Plasmas. Quantum Kinetics


  We implement the dynamical renormalization group (DRG) using the hard thermal
loop (HTL) approximation for the real-time nonequilibrium dynamics in hot
plasmas. The focus is on the study of the relaxation of gauge and fermionic
mean fields and on the quantum kinetics of the photon and fermion distribution
functions. As a concrete physical prediction, we find that for a QGP of
temperature T sim 200 MeV and lifetime 10 < t < 50 fm/c there is a new
contribution to the hard (k \sim T) photon production from off-shell
bremsstrahlung (q rightarrow q gamma and bar{q} rightarrow bar{q} gamma) at
just O (alpha) that grows logarithmically in time and is comparable to the
known on-shell Compton scattering and pair annihilation at O(alpha alpha_s).

</DOC>
<DOC>
<DOCNO> 69934 </DOCNO>
Precision Predictions for (Un)Stable W+W- Pair Production At and Beyond


  We present precision calculations of the processes e+e- -> 4-fermions in
which the double resonant W+W- intermediate state occurs. Referring to this
latter intermediate state as the 'signal process', we show that, by using the
YFS Monte Carlo event generators YFSWW3-1.14 and KORALW1.42 in an appropriate
combination, we achieve a physical precision on the signal process, as isolated
with LEP2 MC Workshop cuts, below 0.5 per cent. We stress the full gauge
invariance of our calculations and we compare our results with those of other
authors where appropriate. In particular, sample Monte Carlo data are
explicitly illustrated and compared with the results of the program RacoonWW of
Dittmaier {\it et al.}. In this way, we show that the total (physical plus
technical) precision tag for the WW signal process cross section is 0.4 per
cent for 200 GeV, for example. Results are also given for 500 GeV with an eye
toward the LC.

</DOC>
<DOC>
<DOCNO> 120596 </DOCNO>
Superbox - An Efficient Code for Collisionless Galactic Dynamics


  We present Superbox, a particle-mesh code with high resolution sub-grids and
an NGP (nearest grid point) force-calculation scheme based on the second
derivatives of the potential. Superbox implements a fast low-storage
FFT-algorithm, giving the possibility to work with millions of particles on
desk-top computers. Test calculations show energy and angular momentum
conservation to one part in 10^5 per crossing-time. The effects of grid and
numerical relaxation remain negligible, even when these calculations cover a
Hubble-time of evolution. As the sub-grids follow the trajectories of
individual galaxies, the code allows a highly resolved treatment of
interactions in clusters of galaxies, such as high-velocity encounters between
elliptical galaxies and the tidal disruption of dwarf galaxies. Excellent
agreement is obtained in a comparison with a direct-summation N-body code
running on special-purpose Grape3 hardware. The orbital decay of satellite
galaxies due to dynamical friction obtained with Superbox agrees with
Chandrasekhar's treatment when the Coulomb logarithm is approximately 1.5.

</DOC>
<DOC>
<DOCNO> 84493 </DOCNO>
String cosmology versus standard and inflationary cosmology


  This paper presents a review of the basic, model-independent differences
between the pre-big bang scenario, arising naturally in a string cosmology
context, and the standard inflationary scenario. We use an unconventional
approach in which the introduction of technical details is avoided as much as
possible, trying to focus the reader's attention on the main conceptual aspects
of both scenarios. The aim of the paper is not to conclude in favour either of
one or of the other scenario, but to raise questions that are left to the
reader's meditation. Warnings: the paper does not contain equations, and is not
intended as a complete review of all aspects of string cosmology.

</DOC>
<DOC>
<DOCNO> 121018 </DOCNO>
Superhumps in Low-Mass X-Ray Binaries


  We propose a mechanism for the superhump modulations observed in optical
photometry of at least two black hole X-ray transients (SXTs). As in extreme
mass-ratio cataclysmic variables (CVs), superhumps are assumed to result from
the presence of the 3:1 orbital resonance in the accretion disc. This causes
the disc to become non-axisymmetric and precess. However the mechanism for
superhump luminosity variations in low mass X-ray binaries (LMXBs) must differ
from that in CVs, where it is attributed to a tidally-driven modulation of the
disc's viscous dissipation, varying on the beat between the orbital and disc
precession period. By contrast in LMXBs, tidal dissipation in the outer
accretion disc is negligible: the optical emission is overwhelming dominated by
reprocessing of intercepted central X-rays. Thus a different origin for the
superhump modulation is required. Recent observations and numerical simulations
indicate that in an extreme mass-ratio system the disc area changes on the
superhump period. We deduce that the superhumps observed in SXTs arise from a
modulation of the reprocessed flux by the changing area. Therefore, unlike the
situation in CVs, where the superhump amplitude is inclination-independent,
superhumps should be best seen in low-inclination LMXBs, whereas an orbital
modulation from the heated face of the secondary star should be more prominent
at high inclinations. Modulation at the disc precession period (10s of days)
may indicate disc asymmetries such as warping. We comment on the orbital period
determinations of LMXBs, and the possibility and significance of possible
permanent superhump LMXBs.

</DOC>
<DOC>
<DOCNO> 70214 </DOCNO>
Precise Physics of Simple Atoms


  We give a review of experimental and theoretical results on the precision
study of hydrogen-like atoms with low value of the nuclear charge Z.

</DOC>
<DOC>
<DOCNO> 150624 </DOCNO>
New applications of the chiral anomaly


  We describe consequences of the chiral anomaly in the theory of quantum
wires, the (quantum) Hall effect, and of a four-dimensional cousin of the Hall
effect. We explain which aspects of conductance quantization are related to the
chiral anomaly. The four-dimensional analogue of the Hall effect involves the
axion field, whose time derivative can be interpreted as a (space-time
dependent) difference of chemical potentials of left-handed and right-handed
charged fermions. Our four-dimensional analogue of the Hall effect may play a
significant role in explaining the origin of large magnetic fields in the
(early) universe.

</DOC>
<DOC>
<DOCNO> 13109 </DOCNO>
Do As antisites destroy the ferromagnetism of (Ga,Mn)As?


  The effect of the inclusion of As antisites in the diluted magnetic
semiconductor (Ga,Mn)As is studied within density functional theory in the
local spin density approximation. In the case of homogeneous distribution of Mn
ions we find that the ferromagnetism is largely weakened by the presence of the
antisites. This is due to compensation of the free holes which mediate the long
range ferromagnetic order. In contrast, when two Mn ions are coupled through
only one As ion, ferromagnetic and antiferromagnetic order compete. In this
case the magnetic ground state depends on: i) the position of the As antisites
relative to the Mn, and ii) the As antisite concentration. We explain our
results using a model of competing antiferromagnetic super-exchange and
ferromagnetic double-exchange via localized Zener carriers. The strong
dependence of the ferromagnetic order on the microscopic configuration accounts
for the large variation in experimental data

</DOC>
<DOC>
<DOCNO> 13951 </DOCNO>
On the generalized Landau-Zener problem


  During the adiabatic time evolution levels crossing violates the adiabaticity
and makes transitions between levels possible. Conventionally only two energy
levels cross simultaneously. The transition probabilities for this case were
found by Landau and Zener. However, the multilevel crossing happens
systematically rather than occasionally if the Hamiltonian possesses a special
symmetry. The simplest physical realization of the multilevel crossing are the
Zeeman multiplet in a varying magnetic field and an electron in one-dimensional
chain driven by the time-dependent electric field. We present asymptotics of
the transition amplitudes for these kinds of the multilevel crossing. They are
based on an exact solution for a model n-state, time-dependent Schr\"{o}dinger
equation.

</DOC>
<DOC>
<DOCNO> 8846 </DOCNO>
High-precision estimate of g4 in the 2D Ising model


  We compute the renormalized four-point coupling in the 2d Ising model using
transfer-matrix techniques. We greatly reduce the systematic uncertainties
which usually affect this type of calculations by using the exact knowledge of
several terms in the scaling function of the free energy. Our final result is
g4=14.69735(3).

</DOC>
<DOC>
<DOCNO> 8814 </DOCNO>
Statistics of the one-dimensional Riemann walk


  The Riemann walk is the lattice version of the Levy flight. For the
one-dimensional Riemann walk of Levy exponent 0<\alpha<2 we study the
statistics of the support, i.e. the set of visited sites, after t steps. We
consider a wide class of support related observables M(t), including the number
S(t) of visited sites and the number I(t) of sequences of visited sites. For
t->\infty we obtain the asymptotic power laws for the averages, variances, and
correlations of these observables. Logarithmic correction factors appear for
\alpha=2/3 and \alpha=1. Bulk and surface observables have different power laws
for 1\leq\alpha<2. Fluctuations are shown to be universal for 2/3\leq\alpha<2.
This means that in the limit t->\infty the deviations from average \DeltaM(t)
are fully described (i) either by a single M independent stochastic process
(when 2/3\leq\alpha\leq 1) (ii) or by two such processes, one for the bulk and
one for the surface observables (when 1<\alpha<2).

</DOC>
<DOC>
<DOCNO> 119058 </DOCNO>
Cosmic Phase Transitions


  The sequence of phase transitions during the hot history of the universe is
followed within a phenomenological framework. Particular emphasis is put on the
QCD confinement transition, which is at reach under earth laboratory
conditions. A tepid inflationary scenario on the GUT scale with bubble grow at
moderate supercooling is discussed.

</DOC>
<DOC>
<DOCNO> 116397 </DOCNO>
Electron correlation in C_(4N+2) carbon rings: aromatic vs. dimerized


  The electronic structure of C_(4N+2) carbon rings exhibits competing
many-body effects of Huckel aromaticity, second-order Jahn-Teller and Peierls
instability at large sizes. This leads to possible ground state structures with
aromatic, bond angle or bond length alternated geometry. Highly accurate
quantum Monte Carlo results indicate the existence of a crossover between C_10
and C_14 from bond angle to bond length alternation. The aromatic isomer is
always a transition state. The driving mechanism is the second-order
Jahn-Teller effect which keeps the gap open at all sizes.

</DOC>
<DOC>
<DOCNO> 67633 </DOCNO>
The Xi(2230) Meson and The Pomeron Trajectory


  We examine the possibility that the xi(2230) meson is a member of the Pomeron
trajectory. A method of connecting the xi --> p pbar decay width and the pp
cross sections through the Pomeron residue function is presented. We have used
a relativistic, singularity-free form factor to make the analytic continuation
of the residue function between crossed channels. We predict that if the
xi(2230) meson is a Pomeron, then it should have a xi --> p pbar decay width of
about 2 MeV.

</DOC>
<DOC>
<DOCNO> 100278 </DOCNO>
Uniqueness of complex contact structures


  Let X be a complex Fano-manifolds with second Betti-number 1 which carries a
contact structure. It follows from previous work that such a manifold can
always be covered by lines. Thus, it seems natural to consider the geometry of
lines in greater detail.
  In this brief note we show that if x in X is a general point, then all lines
through x are smooth. If X is not the projective space, then the tangent spaces
to lines generate the contact distribution at x. As a consequence we obtain
that the contact structure on X is unique, a result previously obtained by C.
LeBrun in the case that X is a twistor space.

</DOC>
<DOC>
<DOCNO> 12137 </DOCNO>
Collapsed and adsorbed states of a directed polymer chain in


  A phase diagram for a surface interacting long flexible partially directed
polymer chain in a two-dimensional poor solvent where the possibility of
collapse in the bulk exists is determined using exact enumeration method. We
used a model of self attracting self-avoiding walk and evaluated 30 steps in
series. An intermediate phase in between the desorbed collapsed and adsorbed
expanded phases having the conformation of a surface attached globule is found.
The four phases, viz. (i) desorbed expanded, (ii) desorbed collapsed, (iii)
adsorbed expanded, (iv) surface attached globule are found to meet at a
multicritical point. These features are in agreement with those of an isotropic
(or non directed) polymer chain.

</DOC>
<DOC>
<DOCNO> 10515 </DOCNO>
What can nuclear collisions teach us about the boiling of water or the


  Phase transitions in nuclei, small atomic clusters and self-gravitating
systems demand the extension of thermo-statistics to ``Small'' systems. The
main obstacle is the thermodynamic limit. It is shown how the original
definition of the entropy by Boltzmann as the volume of the energy-manifold of
the N-body phase space allows a {\em geometrical} definition of the entropy as
function of the conserved quantities. Without invoking the thermodynamic limit
the whole ``zoo'' of phase transitions and critical points/lines can be
unambiguously defined. The relation to the Yang--Lee singularities of the
grand-canonical partition sum is pointed out. It is shown that just phase
transitions in non-extensive systems give the complete set of characteristic
parameters of the transition {\em including the surface tension.} Nuclear
heavy-ion collisions are an experimental playground to explore this extension
of thermo-statistics

</DOC>
<DOC>
<DOCNO> 72018 </DOCNO>
$K^*(892)$ Electromagnetic Mass Anomaly


  Electromagnetic masses of neutral $K^*(892)$ may be larger than one of
charged $K^*(892)$. It is unusual and is called $K^*$-EM-mass anomaly. We
review the studies on this issue, and point out that $K^*$-mass splitting can
be measured in BES accurately.

</DOC>
<DOC>
<DOCNO> 83109 </DOCNO>
On the semantics of merging


  Intelligent agents are often faced with the problem of trying to merge
possibly conflicting pieces of information obtained from different sources into
a consistent view of the world. We propose a framework for the modelling of
such merging operations with roots in the work of Spohn (1988, 1991). Unlike
most approaches we focus on the merging of epistemic states, not knowledge
bases. We construct a number of plausible merging operations and measure them
against various properties that merging operations ought to satisfy. Finally,
we discuss the connection between merging and the use of infobases Meyer (1999)
and Meyer et al. (2000).

</DOC>
<DOC>
<DOCNO> 122202 </DOCNO>
HI absorption in radio galaxies: effect of orientation or interstellar


  A search for HI absorption has been made in 23 radio galaxies using the ATCA,
the VLA and the WSRT. In five galaxies HI absorption was detected. We
investigate how the detection rate is distributed among galaxies with different
radio and optical properties. Among the Fanaroff-Riley (FR) type I radio
galaxies, only one object (10% of total) was detected. The HI absorption in
these objects is likely to come from a nuclear disk, as found for other
galaxies of this type. The low detection rate is consistent with the hypothesis
(as suggested by optical and X-ray data) that the ``standard'' pc scale,
geometrically thick torus is not required in low-luminosity radio galaxies. In
the case of FR type-II powerful radio galaxies, no HI absorption has been
detected in broad line radio galaxies, while three out of four narrow-line
radio galaxies have been detected (the one non-detection having quite a high
upper limit). All these are compact or small radio galaxies. To first order
this is consistent with the predictions of the unified schemes, assuming that
the HI absorption is due to an obscuring torus. However, the indications of
this being the only cause of the absorption are not very strong. In particular,
we find that in two of the three detected objects that the HI is blueshifted
compared to the systemic velocity. In the third galaxy (PKS 1549-79) two
redshift systems (from the optical lines) are found. The uncertainty in the
systemic velocity derived from optical lines is discussed. Finally, we find a
tendency for radio galaxies with a strong component of young stellar population
and far-IR emission to show HI absorption. The overall richer ISM that is
likely to be present in these galaxies may be a factor in producing the
absorption.

</DOC>
<DOC>
<DOCNO> 99896 </DOCNO>
On some additivity problems in quantum information theory


  A class of problems in quantum information theory, having an elementary
formulation but still resisting solution, concerns the additivity properties of
various quantities characterizing quantum channels, notably the "classical
capacity", and the "maximal output purity". All known results, including
extensive numerical work, are consistent with the conjecture that these
quantities are indeed additive (resp. multiplicative) with respect to tensor
products of channels. A proof of this conjecture would have important
consequences in quantum information theory. In particular, according to this
conjecture, the classical capacity or the maximal purity of outputs cannot be
increased by using entangled inputs of the channel. In this paper we state the
additivity/multiplicativity problems, give some relations between them, and
prove some new partial results, which also support the conjecture.

</DOC>
<DOC>
<DOCNO> 100270 </DOCNO>
Nested Bethe Ansatz and Finite Dimensional Canonical Commutation


  Recent interest in discrete, classical integrable systems has focused on
their connection to quantum integrable systems via the Bethe equations. In this
note, solutions to the rational nested Bethe ansatz (RNBA) equations are
constructed using the ``completed Calogero-Moser phase space'' of matrices
which satisfy a finite dimensional analogue of the canonical commutation
relationship. A key feature is the fact that the RNBA equations are derived
only from this commutation relationship and some elementary linear algebra. The
solutions constructed in this way inherit continuous and discrete symmetries
from the CM phase space.

</DOC>
<DOC>
<DOCNO> 11133 </DOCNO>
Measurements of the absolute value of the penetration depth in high-$


  A method is presented to measure the absolute value of the London penetration
depth, $\lambda$, from the frequency shift of a resonator. The technique
involves coating a high-$T_c$ superconductor (HTSC) with film of low - Tc
material of known thickness and penetration depth. The method is applied to
measure London penetration depth in YBa2Cu3O{7-\delta} (YBCO)
Bi2Sr2CaCu2O{8+\delta} (BSCCO) and Pr{1.85}Ce{0.15}CuO{4-\delta}$ (PCCO). For
YBCO and BSCCO, the values of $\lambda (0)$ are in agreement with the
literature values. For PCCO $\lambda \approx 2790$ \AA, reported for the first
time.

</DOC>
<DOC>
<DOCNO> 101458 </DOCNO>
An Elementary Problem Equivalent to the Riemann Hypothesis


  This paper shows the equivalence of the Riemann hypothesis to an sequence of
elementary inequalities involving the harmonic numbers H_n, the sum of the
reciprocals of the integers from 1 to n. It is a modification of a criterion
due to Guy Robin.

</DOC>
<DOC>
<DOCNO> 101852 </DOCNO>
Hall invariants, homology of subgroups, and characteristic varieties


  Given a finitely-generated group G, and a finite group \Gamma, Philip Hall
defined \delta_\Gamma to be the number of factor groups of G that are
isomorphic to \Gamma. We show how to compute the Hall invariants by
cohomological and combinatorial methods, when G is finitely-presented, and
\Gamma belongs to a certain class of metabelian groups. Key to this approach is
the stratification of the character variety by the jumping loci of the
cohomology of G, with coefficients in rank 1 local systems over a suitably
chosen field \K. Counting relevant torsion points on these "characteristic"
subvarieties gives \delta_\Gamma(G). In the process, we compute the
distribution of prime-index, normal subgroups K of G according to the dimension
of the the first homology group of K with \K coefficients, provided \char\K
does not divide the index of K in G. In turn, we use this distribution to count
low-index subgroups of G. We illustrate these techniques in the case when G is
the fundamental group of the complement of an arrangement of either affine
lines in \C^2, or transverse planes in \R^4.

</DOC>
<DOC>
<DOCNO> 100062 </DOCNO>
Exponentially decaying eigenvectors for certain almost periodic


  For certain one-dimensional Schroedinger-type difference operators with a
complex potential, a "complete" set of exponentially decaying eigenvectors is
shown to exist. "Completeness" entails that the parameters involved are
obtained through evaluation of analytic functions on a Riemann surface.

</DOC>
<DOC>
<DOCNO> 12548 </DOCNO>
Growth of (110) Diamond using pure Dicarbon


  We use a density-functional based tight-binding method to study diamond
growth steps by depositing dicarbon species onto a hydrogen-free diamond (110)
surface. Subsequent C_2 molecules are deposited on an initially clean surface,
in the vicinity of a growing adsorbate cluster, and finally, near vacancies
just before completion of a full new monolayer. The preferred growth stages
arise from C_2n clusters in near ideal lattice positions forming zigzag chains
running along the [-110] direction parallel to the surface. The adsorption
energies are consistently exothermic by 8--10 eV per C_2, depending on the size
of the cluster. The deposition barriers for these processes are in the range of
0.0--0.6 eV. For deposition sites above C_2n clusters the adsorption energies
are smaller by 3 eV, but diffusion to more stable positions is feasible. We
also perform simulations of the diffusion of C_2 molecules on the surface in
the vicinity of existing adsorbate clusters using an augmented Lagrangian
penalty method. We find migration barriers in excess of 3 eV on the clean
surface, and 0.6--1.0 eV on top of graphene-like adsorbates. The barrier
heights and pathways indicate that the growth from gaseous dicarbons proceeds
either by direct adsorption onto clean sites or after migration on top of the
existing C_2n chains.

</DOC>
<DOC>
<DOCNO> 69465 </DOCNO>
Mixing of the $f_0$ and $a_0$ scalar mesons in threshold photoproduction


  We examine the photoproduction of the light scalar mesons $f_0$-$a_0 (980)$
with emphasis on isospin-violating $f_0$ and $a_0$ mixing due to the mass
difference between neutral and charged kaons. General forms for the invariant
amplitude for scalar meson photoproduction are derived, which yield expressions
for the invariant mass distribution of the final meson pairs. A final state
interaction form factor is obtained which incorporates $f_0$ and $a_0$ mesons,
$K\bar K$ threshold effects, and $f_0-a_0$ mixing. This form factor is applied
to predict the effective mass distribution of the $\pi\pi$ and $K\bar K$ pairs
in the vicinity of the $K\bar K$ threshold. An estimate of the role of isospin
mixing near threshold is provided. The potential role of polarized photons and
protons is also discussed.

</DOC>
<DOC>
<DOCNO> 8781 </DOCNO>
Sub-aging in a Domain Growth Model


  We study analytically the aging dynamics of the O(n) model in the large-n
limit, with conserved and with non-conserved order parameter. While in the
non-conserved dynamics, the autocorrelation function scales in the usual way
C(t,tw) = C(t/tw), in the case of a conserved order parameter, `multiscaling'
manifests itself in the form C(t,tw) = C (h(t)/h(tw)), with a relaxation time
growing more slowly than the age of the system (sub-aging), and h(t) a function
growing faster than any length scale of the problem. In both cases, the
effective temperature associated to the violation of the fluctuation theorem
tends to infinity in the asymptotic limit of large waiting times.

</DOC>
<DOC>
<DOCNO> 39687 </DOCNO>
Insight into the Scalar Mesons from a Lattice Calculation


  We study the possibility that the light scalar mesons are (qbar qbar q q)
states rather than (qbar q). We perform a lattice QCD calculation of
pseudoscalar meson scattering amplitudes, ignoring quark loops and quark
annihilation, and find indications that for sufficiently heavy quarks there is
a stable four-quark bound state with J^{PC}=0^{++} and non-exotic flavor
quantum numbers.

</DOC>
<DOC>
<DOCNO> 120025 </DOCNO>
Anisotropic Galaxy-Galaxy Lensing


  We investigate the weak lensing shear due to dark matter galaxy halos whose
mass distributions, as projected on the sky, are nearly elliptical. The shear
pattern due to these halos is anisotropic about the lens centers and we
quantify the level of anisotropy by comparing the mean shear experienced by
sources located closest to the major axes of the lenses $<\gamma>_{major}$, to
that experienced by sources located closest to the minor axes,
$<\gamma>_{minor}$. We also compute the degree to which the anisotropy in the
lensing signal is degraded due to a noisy determination of the position angles
of the lens galaxies and find that provided the typical error on the
orientation of the lenses is less than $15^\circ$, more than 90% of the true
lensing signal is recovered in the mean. We discuss our our results in the
context of detecting anisotropic galaxy-galaxy lensing in large, ground-based
data sets and conclude that a modest net flattening of dark matter halos should
be detectable at a statistically significant level. The forthcoming Sloan
Digital Sky Survey (SDSS) data will necessarily provide a very useful data set
for this analysis, but a detection of anisotropic galaxy-galaxy lensing is not
dependent upon the very large sky coverage of the SDSS. Rather, we argue that a
significant detection of this effect can also be obtained from an imaging
survey that is of order two magnitudes fainter than SDSS and which covers only
a relatively small area of sky, of order one square degree. [Abridged]

</DOC>
<DOC>
<DOCNO> 83065 </DOCNO>
Query Complexity: Worst-Case Quantum Versus Average-Case Classical


  In this note we investigate the relationship between worst-case quantum query
complexity and average-case classical query complexity. Specifically, we show
that if a quantum computer can evaluate a total Boolean function f with bounded
error using T queries in the worst case, then a deterministic classical
computer can evaluate f using O(T^5) queries in the average case, under a
uniform distribution of inputs. If f is monotone, we show furthermore that only
O(T^3) queries are needed. Previously, Beals et al. (1998) showed that if a
quantum computer can evaluate f with bounded error using T queries in the worst
case, then a deterministic classical computer can evaluate f using O(T^6)
queries in the worst case, or O(T^4) if f is monotone. The optimal bound is
conjectured to be O(T^2), but improving on O(T^6) remains an open problem.
Relating worst-case quantum complexity to average-case classical complexity may
suggest new ways to reduce the polynomial gap in the ordinary worst-case versus
worst-case setting.

</DOC>
<DOC>
<DOCNO> 9622 </DOCNO>
Driven vortices in 3D layered superconductors: Dynamical ordering along


  We study a 3D model of driven vortices in weakly coupled layered
superconductors with strong pinning. Above the critical force $F_c$, we find a
plastic flow regime in which pancakes in different layers are uncoupled,
corresponding to a pancake gas. At a higher $F$, there is an ``smectic flow''
regime with short-range interlayer order, corresponding to an entangled line
liquid. Later, the transverse displacements freeze and vortices become
correlated along the c-axis, resulting in a transverse solid. Finally, at a
force $F_s$ the longitudinal displacements freeze and we find a coherent solid
of rigid lines.

</DOC>
<DOC>
<DOCNO> 118926 </DOCNO>
On the Role of Minor Galaxy Mergers in the Formation of Active Galactic


  The large scale (~ 100 kpc) environments of Seyfert galaxies are not
significantly different from those of non-Seyfert galaxies. In the context of
the interaction model of the formation of active galactic nuclei (AGN), it has
been proposed that AGN form via "minor mergers" of large disk galaxies with
smaller companions. We test this hypothesis by comparing the nuclear spectra of
105 bright nearby galaxies with measurements of their R or r band morphological
asymmetries at three successive radii. We find no significant differences in
these asymmetries between the 13 Seyfert galaxies in the sample and galaxies
having other nuclear spectral types (absorption, H II-region like, LINER), nor
is there strong qualitative evidence that such mergers have occured among any
of the Seyferts or LINERs. Thus either any minor mergers began > 1 Gyr ago and
are essentially complete, or they did not occur at all, and AGN form
independently of any type of interaction. Support for the latter interpretation
is provided by the growing evidence that supermassive black holes exist in the
cores of most elliptical and early-type spiral galaxies, which in turn suggests
that nuclear activity represents a normal phase in the evolution of the bulges
of massive galaxies. Galaxy mergers may increase the luminosity of Seyfert
nuclei to the level of QSOs, which could explain why the latter objects appear
to be found in rich environments and in interacting systems.

</DOC>
<DOC>
<DOCNO> 151317 </DOCNO>
Critical fields on the M5-brane and noncommutative open strings


  The M5-brane is investigated near critical field-strength. We show that this
limit on the M5-brane reduces to the noncommutative open string limit on the
D4-brane. The reduction on a two-torus leads to both the noncommutative open
string limit and the noncommutative Yang-Mills limit on the D3-brane. The
decoupled noncommutative five-brane is identified with the strong coupling
limit of the noncommutative open string theory on the D4-brane and S-duality on
the noncommutative D3-brane is identified with a modular transformation on the
five-brane. We argue that the open membrane metric defines a finite length
scale on the worldvolume of the M5-brane in the decoupling limit. This length
scale can be associated to the effective length scale of an open membrane.

</DOC>
<DOC>
<DOCNO> 122090 </DOCNO>
The very lithium rich post-AGB SB2 binary HD172481


  Double lined spectroscopic binaries in an evolved stage of evolution are
expected to be extremely rare since they must consist of equally luminous and
thus almost equally evolved objects, which requires an extremely similar
initial mass. In this contribution we discuss such rare double evolved SB2
system: HD172481. This binary includes an F-type post-AGB object and an M-type
AGB companion. The spectrum shows a surprisingly strong LiI 670.8nm line with
an equivalent width of 54mA yielding a lithium abundance of log(Li)=3.6.
Several explanations for this huge lithium content are explored.

</DOC>
<DOC>
<DOCNO> 118699 </DOCNO>
Galactic Evolution of Beryllium and Oxygen


  We discuss the early evolution of beryllium and oxygen in our Galaxy by
comparing abundances of these elements for halo and disk metal-poor stars.
Both, O and Be rise as we go progressively to more metal-rich stars, showing a
slope 0.41 +-0.09 ([Be/O] vs [Fe/H]) for stars with [Fe/H] < -1. This
relationship provides an observational constraint to the actually proposed
Galactic Cosmic Ray theories.

</DOC>
<DOC>
<DOCNO> 70574 </DOCNO>
Small-x Processes in Perturbative Quantum Chromodynamics


  Starting from a rewiev of DGLAP and BFKL evolution equations for small-x
processes, a sistematic study is performed in order to understand the limits of
both the formulations and to improve them in a unique framework, which aims to
cover the whole range of applicability of perturbative QCD and which describes
the transition mechanism from perturbative to non-perturbative physics in the
region where unitarity contributions are expected not to be important.

</DOC>
<DOC>
<DOCNO> 68519 </DOCNO>
Supersymmetric Electroweak Corrections to Charged Higgs Boson Production


  We calculate the $O(\alpha_{ew}m_{t(b)}^{2}/m_{W}^{2})$ and $O(\alpha_{ew}
m_{t(b)}^4/m_W^4)$ supersymmetric electroweak corrections to the cross section
for the charged Higgs boson production in association with a top quark at the
Tevatron and the LHC. These corrections arise from the quantum effects which
are induced by potentially large Yukawa couplings from the Higgs sector and the
chargino-top(bottom)-sbottom(stop) couplings,
neutralino-top(bottom)-stop(sbottom) couplings and charged Higgs-stop-sbottom
couplings. They can decrease or increase the cross section depending on
$\tan\beta$ but are not very sensitive to the mass of the charged Higgs boson
for high $\tan\beta$. At low $\tan\beta(=2)$ the corrections decrease the total
cross sections significantly, which exceed -12% for $m_{H^{\pm}}$ below
$300GeV$ at both the Tevatron and the LHC, but for $m_{H^{\pm}}>300GeV$ the
corrections can become very small at the LHC. For high $\tan\beta(=10,30)$
these corrections can decrease or increase the total cross sections, and the
magnitude of the corrections are at most a few percent at both the Tevatron and
the LHC.

</DOC>
<DOC>
<DOCNO> 152145 </DOCNO>
Standard Cosmology on a Self-Tuning Domain Wall


  We investigate the cosmology of (4+1)-dimensional gravity coupled to a scalar
field and a bulk anisotropic fluid within the context of the single-brane
Randall-Sundrum scenario. Assuming a separable metric, a static fifth radius
and the scalar to depend only on the fifth direction, we find that the warp
factor is given as in the papers of Kachru, Schulz and Silverstein
[hep-th/0001206, hep-th/0002121] and that the cosmology on a self-tuning brane
is standard. In particular, for a radiation-dominated brane the pressure in the
fifth direction vanishes.

</DOC>
<DOC>
<DOCNO> 39885 </DOCNO>
Resonance structure of tau->Kpipi decays


  Using a sample of 4.7/fb integrated luminosity accumulated with the CLEO II
detector at the Cornell Electron Storage Ring (CESR), we investigate the mass
spectrum and resonant structure in tau->Kpipi decays. We measure the relative
fractions of K1(1270) and K1(1400) resonances in these decays, as well as the
K1 masses and widths. Our fitted K1 resonances are somewhat broader than
previous hadroproduction measurements, and in agreement with recent LEP results
from tau decay. The larger central value of our measured width supports models
which attribute the small tau->Kpipi branching fraction to larger K1 widths
than are presently tabulated. We also determine the Ka-Kb mixing angle theta_K.

</DOC>
<DOC>
<DOCNO> 121657 </DOCNO>
On the origin of the O and B-type stars with high velocities II Runaway


  We use milli-arcsecond accuracy astrometry (proper motions and parallaxes)
from Hipparcos and from radio observations to retrace the orbits of 56 runaway
stars and nine compact objects with distances less than 700 pc, to identify the
parent stellar group. It is possible to deduce the specific formation scenario
with near certainty for two cases. (i) We find that the runaway star zeta
Ophiuchi and the pulsar PSR J1932+1059 originated about 1 Myr ago in a
supernova explosion in a binary in the Upper Scorpius subgroup of the Sco OB2
association. The pulsar received a kick velocity of about 350 km/s in this
event, which dissociated the binary, and gave zeta Oph its large space
velocity. (ii) Blaauw & Morgan and Gies & Bolton already postulated a common
origin for the runaway-pair AE Aur and mu Col, possibly involving the massive
highly-eccentric binary iota Ori, based on their equal and opposite velocities.
We demonstrate that these three objects indeed occupied a very small volume
\sim 2.5Myr ago, and show that they were ejected from the nascent Trapezium
cluster.
  We identify the parent group for two more pulsars: both likely originate in
the 50 Myr old association Per OB3, which contains the open cluster alpha
Persei. At least 21 of the 56 runaway stars in our sample can be linked to the
nearby associations and young open clusters. These include the classical
runaways 53 Arietis (Ori OB1), xi Persei (Per OB2), and lambda Cephei (Cep
OB3), and fifteen new identifications, amongst which a pair of stars running
away in opposite directions from the region containing the lambda Ori cluster.
Other currently nearby runaways and pulsars originated beyond 700 pc, where our
knowledge of the parent groups is very incomplete.

</DOC>
<DOC>
<DOCNO> 11118 </DOCNO>
Cluster Percolation in O(n) Spin Models


  The spontaneous symmetry breaking in the Ising model can be equivalently
described in terms of percolation of Wolff clusters. In O(n) spin models
similar clusters can be built in a general way, and they are currently used to
update these systems in Monte Carlo simulations. We show that for 3-dimensional
O(2), O(3) and O(4) such clusters are indeed the physical `islands' of the
systems, i.e., they percolate at the physical threshold and the percolation
exponents are in the universality class of the corresponding model. For O(2)
and O(3) the result is proven analytically, for O(4) we derived it by numerical
simulations.

</DOC>
<DOC>
<DOCNO> 119326 </DOCNO>
Effects of Luminosity Functions Induced by Relativistic Beaming on


  We study the effects of the beaming-induced luminosity function on statistics
of observed GRBs, assuming the cosmological scenario. We select and divide the
BATSE 4B data into 588 long bursts (T$_{90}>2.5$ sec) and 149 short bursts
(T$_{90}<2.5$ sec), and compare the statistics calculated in each subgroup. The
$<V/V_{\rm max}>$ of the long bursts is $ 0.2901\pm 0.0113$, and that of the
short bursts is $0.4178\pm 0.0239$, which is a Euclidean value. For luminosity
function models, we consider a cylindrical-beam and a conic-beam. We take into
account the spatial distribution of GRB sources as well. A broad luminosity
function is naturally produced when one introduces beaming of GRBs. We
calculate the maximum detectable redshift of GRBs, $z_{\rm max}$. The estimated
$z_{\rm max}$ for the cylindrical-beam case is as high as $\sim 14$ for the
long bursts and $\sim 3$ for the short bursts. The large $z_{\rm max}$ value
for the short bursts is rather surprising in that the $<V/V_{\rm max}>$ for
this subgroup is close to the so-called Euclidean value, 0.5. We calculate the
fraction of bursts whose redshifts are larger than a certain redshift $z'$,
i.e. $f_{\rm > z'}$. When we take $z'=3.42$ and apply the luminosity function
derived for the cylindrical-beam, the expected $f_{\rm > z'}$ is $\sim 75 %$
for long bursts. When we increase the opening angle of the conic beam to
$\Delta \theta =3^\circ.0$, $f_{\rm > z'}$ decreases to $\sim 20 %$ at $ {\rm
z'=3.42}$. We conclude that the beaming-induced luminosity functions are
compatible with the redshift distribution of observed GRBs and that the
apparent Euclidean value of $<V/V_{\rm max}>$ may not be due to the Euclidean
space distribution but to the luminosity distribution.

</DOC>
<DOC>
<DOCNO> 151567 </DOCNO>
Quantum corrections for (anti)-evaporating black hole


  In this paper we analyse the quantum correction for Schwarzschild black hole
in the Unruh state in the framework of spherically symmetric gravity (SSG)
model. SSG is a two-dimensional dilaton model which is obtained by spherically
symmetric reduction from the four-dimensional theory. We find the one-loop
geometry of the (anti)-evaporating black hole and corrections for mass, entropy
and apparent horizon.

</DOC>
<DOC>
<DOCNO> 122691 </DOCNO>
Population synthesis of neutron stars, strange (quark) stars and black


  We compute and present the distribution in mass of single and binary neutron
stars, strange stars, and black holes. The calculations were performed using a
stellar population synthesis code. We follow all phases of single and binary
evolution, starting from a ZAMS binary and ending in the creation of one
compact object (neutron star, black hole, strange star) and a white dwarf, or
two compact objects (single or binary). We assume that neutron stars are formed
in the collapse of iron/nickel cores in the mass range M0 < M < M1, quark stars
in the range M1 < M < M2, and black holes for core masses M > M2 and find that
the population of quark stars can easily be as large as the population of black
holes, even if there is only a small mass window for their formation.

</DOC>
<DOC>
<DOCNO> 69177 </DOCNO>
Effective Field Theory For Nuclei: Confronting Fundamental Questions in


  Fundamental issues involving nuclei in the celebrated solar neutrino problem
are discussed in terms of an effective field theory adapted to nuclear few-body
systems, with a focus on the proton fusion process and the hep process. Our
strategy in addressing these questions is to combine chiral perturbation theory
-- an effective field theory of QCD -- with an accurate nuclear physics
approach to arrive at a more effective effective field theory that reveals and
exploits a subtle role of the chiral-symmetry scale in short-distance effects
encoded in short-range nuclear correlations. Our key argument is drawn from the
close analogy of the principal weak matrix element figuring in the hep process
to the suppressed matrix elements in the polarized neutron-proton capture at
threshold currently being measured in the laboratories.

</DOC>
<DOC>
<DOCNO> 121769 </DOCNO>
Big-Bang Nucleosynthesis Predictions for Precision Cosmology


  The determination of the primeval deuterium abundance has opened a precision
era in big-bang nucleosynthesis (BBN), making accurate predictions more
important than ever before. We present in analytic form new, more precise
predictions for the light-element abundances and their error matrix. Using our
predictions and the primeval deuterium abundance we infer a baryon density of
Omega_B h^2 = 0.020 pm 0.002 (95% cl) and find no evidence for stellar
production (or destruction) of 3He beyond burning D to 3He. Conclusions about
4He and 7Li currently hinge upon possible systematic error in their
measurements.

</DOC>
<DOC>
<DOCNO> 85547 </DOCNO>
The quasi-classical model of the spherical configuration in general


  We consider the quasi-classical model of the spin-free configuration on the
basis of the self-gravitating spherical dust shell in General Relativity. For
determination of the energy spectrum of the stationary states on the basis of
quasi-classical quantization rules it is required to carry out some
regularization of the system. It is realized by an embedding of the initial
system in the extended system with rotation. Then, the stationary states of the
spherical shells are S-states of the system with the intrinsic momentum. The
quasi-classical treatment of a stability of the configuration is associated
with the Langer modification of a square of the quantum mechanical intrinsic
momentum. It gives value of critical bare mass of the shell determining
threshold of stability. For the shell with the bare mass smaller or equal to
the Planck's mass, the energy spectra of bound states are found. We obtain the
expression for tunneling probability of the shell and construct the
quasi-classical model of the pair creation and annihilation of the shells.

</DOC>
<DOC>
<DOCNO> 150677 </DOCNO>
Classification of constraints using chain by chain method


  We introduce "chain by chain" method for constructing the constraint
structure of a system possessing both first and second class constraints. We
show that the whole constraints can be classified into completely irreducible
first or second class chains. We found appropriate redefinition of second class
constraints to obtain a symplectic algebra among them.

</DOC>
<DOC>
<DOCNO> 11074 </DOCNO>
A simple interpretation of quantum mirages


  In an interesting new experiment the electronic structure of a magnetic atom
adsorbed on the surface of Cu(111), observed by STM, was projected into a
remote location on the same surface. The purpose of the present paper is to
interpret this experiment with a model Hamiltonian, using ellipses of the size
of the experimental ones, containing about 2300 atoms. The charge distribution
for the different wavefunctions is analyzed, in particular, for those with
energy close to the Fermi energy of copper Ef. Some of them show two symmetric
maxima located on the principal axis of the ellipse but not necessarily at the
foci. If a Co atom is adsorbed at the site where the wavefunction with energy
$E_F$ has a maximum and the interaction is small, the main effect of the
adsorbed atom will be to split this particular wavefunction in two. The total
charge density will remain the same but the local density of states will
present a dip at Ef at any site where the charge density is large enough. We
relate the presence of this dip to the observation of quantum mirages. Our
interpretation suggests that other sites, apart from the foci of the ellipses,
can be used for projecting atomic images and also indicates the conditions for
other non magnetic adsorbates to produce mirages.

</DOC>
<DOC>
<DOCNO> 102336 </DOCNO>
Generalized fixed point algebras and square-integrable group actions


  We analzye Rieffel's construction of generalized fixed point algebras in the
setting of group actions on Hilbert modules. Let G be a locally compact group
acting on a C*-algebra B. We construct a Hilbert module F over the reduced
crossed product of G and B, using a pair (E, R), where E is an equivariant
Hilbert module over B and R is a dense subspace of E with certain properties.
The generalized fixed point algebra is the C*-algebra of compact operators on
F. Any Hilbert module over the reduced crossed product arises by this
construction for a pair (E, R) that is unique up to isomorphism.
  A necessary condition for the existence of R is that E be square-integrable.
The consideration of square-integrable representations of Abelian groups on
Hilbert space shows that this condition is not sufficient and that different
choices for R may yield different generalized fixed point algebras.
  If B is proper in Kasparov's sense, there is a unique R with the required
properties. Thus the generalized fixed point algebra only depends on E.

</DOC>
<DOC>
<DOCNO> 70245 </DOCNO>
Super Yang-Mills on the lattice with domain wall fermions


  The dynamical N=1, SU(2) Super Yang-Mills theory is studied on the lattice
using a new lattice fermion regulator, domain wall fermions. This formulation
even at non-zero lattice spacing does not require fine-tuning, has improved
chiral properties and can produce topological zero-mode phenomena. Numerical
simulations of the full theory on lattices with the topology of a torus
indicate the formation of a gluino condensate which is sustained at the chiral
limit. The condensate is non-zero even for small volume and small supersymmetry
breaking mass where zero mode effects due to gauge fields with fractional
topological charge appear to play a role.

</DOC>
<DOC>
<DOCNO> 11350 </DOCNO>
Orthogonality catastrophe and decoherence of a confined Bose-Einstein


  We discuss mechanisms of decoherence of a confined Bose-Einstein condensate
at finite temperatures under the explicit condition of conservation of the
total number of bosons $N$ in the trap. A criterion for the irreversible decay
of the condensate two-time correlator is formulated in terms of the {\it
Orthogonality Catastrophe} (OC) for the exact N-body eigenstates, so that no
irreversible decay occurs without the OC. If an infinite external bath contacts
a finite condensate, the OC should practically always occur as long as the bath
degrees o freedom are interacting with each other. We claim that, if no
external bath is present and the role of the bath is played by the normal
component, no irreversible decay occurs. We discuss the role of the effect of
the {\it level repulsion} in eliminating the OC. At finite temperatures, the
time-correlations of the condensate isolated from the environment are dominated
by the reversible dephasing which results from the thermal ensemble averaging
over realizations of the normal component. Accordingly, the correlator exhibits
the gaussian decay with certain decay time $\tau_d$ dependent on temperature as
well as on intensity of the shot noise determined by the statistical
uncertainty in the number of bosons $N$ deposited into the trap. We estimate
$\tau_d$ for the conditions resembling those realized in the JILA experiment,
and obtain the value close to 1s, if no shot noise is taken into account. At
temperatures as large as 0.5 of the temperature of the Bose-Einstein
condensation, $\tau_d \leq 100$ms. Depending on the variance $\Delta N$ of $N$,
inclusion of the shot noise may shorten these times.

</DOC>
<DOC>
<DOCNO> 117482 </DOCNO>
Hubble Space Telescope Imaging of the Young Planetary Nebula GL 618


  We present narrow-band Hubble Space Telescope images of the young planetary
nebula GL 618. These images have allowed us to study the detailed morphology of
shock-excited emission present in the bipolar lobes of this object. These
images reveal the presence of three highly collimated outflows emanating from
the central regions of GL 618. We discuss the significance of the detection of
these outflows and the possible origins of these features.

</DOC>
<DOC>
<DOCNO> 69702 </DOCNO>
Search for SUSY with R-Parity Violation at gamma-proton and


  We present an outlook for possible R-parity violating SUSY search at
gamma-proton and gamma-electron colliders. Single production of third
generation slepton/sneutrino through the lambda'-ijk couplings at a gamma-p
collider is investigated and compared with the results of the resonant sfermion
productions at the existing colliders. Also single sneutrino production at a
future gamma-electron collider through the lambda(ijk) couplings is disussed.

</DOC>
<DOC>
<DOCNO> 117574 </DOCNO>
Search for Relic Neutrinos and Supernova Bursts


  We describe the current situation concerning methods to search for relic
neutrinos from the Big Bang and from all past supernovae (SNs). The most
promising method for Big Bang neutrinos is by the interaction of ultra-high-
energy (UHE) neutrinos. For supernova neutrinos, both Super Kamiokande- and
ICARUS-type detectors will be important to study both nubar_{e} and nu_{e}
fluxes. We also discuss a dedicated supernova burst observatory (OMNIS) being
planned for three sites in the world. We also describe the possible analysis of
the supernova type-II (SNII) neutrinos, including flavor mixing, that might be
carried out in the future.

</DOC>
<DOC>
<DOCNO> 100202 </DOCNO>
Penalty approximation for non smooth constraints in vibroimpact


  We examine the penalty approximation of the free motion of a material point
in an angular domain; we choose an over-damped penalty, and we prove that if
the first impact point is not at the vertex, then, the limit of the
approximation exists and is described by Moreau's rule for anelastic impacts.
  The proofs rely on validated asymptotics and use some classical tools in the
theory of dynamical systems.

</DOC>
<DOC>
<DOCNO> 71371 </DOCNO>
Properties of the tensor mesons $f_2(1270)$ and $f^\prime_2(1525)$


  In the $f_2(1270)-f^\prime_2(1525)$ mixing framework, the isoscalar
singlet-octet mixing angle for 1$^3P_2$ tensor nonet is determined to be the
value of $27.5^\circ$ and the decays of the two states are investigated.
Comparing the predicted results of the decays of the two states with the
available experimental data, we find that the predicted results are in good
agreement with the experimental data, which shows that the $f_2(1270)$ and
$f^\prime_2(1525)$ wave functions don't need other components such as glueballs
or the 2 $^3P_2$,3 $^3P_2$,...$q\bar{q}$.

</DOC>
<DOC>
<DOCNO> 100457 </DOCNO>
Generalized Master Function Approach to Quasi-Exactly Solvable Models


  By introducing the generalized master function of order up to four together
with corresponding weight function, we have obtained all quasi-exactly solvable
second order differential equations. It is shown that these differntial
equations have solutions of polynomial type with factorziation properties, that
is polynomial solutions Pm(E) can be factorized in terms of polynomial Pn(E)
for m not equal to n. All known quasi-exactly quantum solvable models can be
obtained from these differential equations, where roots of polynomial Pn(E) are
corresponding eigen-values.

</DOC>
<DOC>
<DOCNO> 85284 </DOCNO>
Parameterized Absolute Parallelism: A Geometry for Physical Applications


  Absolute parallelism (AP) geometry is frequently used for physical
applications. Although it is wider than Riemannian geometry, it has two main
defects. The first is that its path equation does not represent physical
trajectories of any test particle. The second is the identical vanishing of its
curvature tensor. The present work shows that parameterizing this geometry
would solve the two problems. Furthermore, the resulting parameterized
AP-structure is more general than both the conventional AP-structure and the
Riemannian structure. Also, it is shown that it can be reduced to one or the
other, of these two geometric structures, in some special cases. The structure
obtained is more appropriate for physical applications, especially in
constructing field theories gauging gravity.

</DOC>
<DOC>
<DOCNO> 14035 </DOCNO>
Effective interactions between star polymers and colloidal particles


  Using monomer-resolved Molecular Dynamics simulations and theoretical
arguments based on the radial dependence of the osmotic pressure in the
interior of a star, we systematically investigate the effective interactions
between hard, colloidal particles and star polymers in a good solvent. The
relevant parameters are the size ratio q between the stars and the colloids, as
well as the number of polymeric arms f (functionality) attached to the common
center of the star. By covering a wide range of q's ranging from zero (star
against a flat wall) up to about 0.75, we establish analytical forms for the
star-colloid interaction which are in excellent agreement with simulation
results. A modified expression for the star-star interaction for low
functionalities, f < 10 is also introduced.

</DOC>
<DOC>
<DOCNO> 85511 </DOCNO>
Black holes with topologically nontrivial AdS asymptotics


  Asymptotically locally AdS black hole geometries of dimension d > 2 are
studied for nontrivial topologies of the transverse section. These geometries
are static solutions of a set of theories labeled by an integer 0 < k <
[(d-1)/2] which possess a unique globally AdS vacuum. The transverse sections
of these solutions are d-2 surfaces of constant curvature, allowing for
different topological configurations. The thermodynamic analysis of these
solutions reveals that the presence of a negative cosmological constant is
essential to ensure the existence of stable equilibrium states. In addition, it
is shown that these theories are holographically related to [(d-1)/2] different
conformal field theories at the boundary.

</DOC>
<DOC>
<DOCNO> 118466 </DOCNO>
Giant Cyclones in Gaseous Discs of Spiral Galaxies


  We report detection of giant cyclonic vortices in the gaseous disc of the
spiral galaxy NGC 3631 in the reference frame rotating with the spiral pattern.
A presence of such structures was predicted by the authors for galaxies, where
the radial gradient of the perturbed velocity exceeds that of the rotational
velocity. This situation really takes place in NGC 3631.

</DOC>
<DOC>
<DOCNO> 121627 </DOCNO>
Groups and clusters detection on DPOSS catalogs


  We discuss the implementation and validation of a procedure aimed to detect
groups and clusters of galaxies in DPOSS catalogs.

</DOC>
<DOC>
<DOCNO> 12909 </DOCNO>
Spintronics and Quantum Computing: Switching Mechanisms for Qubits


  Quantum computing and quantum communication are remarkable examples of new
information processing technologies that arise from the coherent manipulation
of spins in nanostructures. We review our theoretical proposal for using
electron spins in quantum-confined nanostructures as qubits. We present single-
and two-qubit gate mechanisms in laterally as well as vertically coupled
quantum dots and discuss the possibility to couple spins in quantum dots via
exchange or superexchange. In addition, we propose a new stationary wave
switch, which allows to perform quantum operations with quantum dots or
spin-1/2 molecules placed on a 1D or 2D lattice.

</DOC>
<DOC>
<DOCNO> 8737 </DOCNO>
A modified dual-slope method for heat capacity measurements of


  A high resolution non-adiabatic method for measuring the heat capacity
($C_v$) of bulk samples of condensable gases in the range 7.5-70 K is
described. In this method $C_v$ is evaluated by directly comparing the heating
and cooling rates of the sample temperature for two algebraically independent
heat pulse sequences without explicit use of the thermal conductance between
sample and thermal bath. A fully automated calorimeter for rapid measurement of
$C_v$ of molecular solids utilizing this technique is presented.

</DOC>
<DOC>
<DOCNO> 40120 </DOCNO>
First symmetry tests in polarized Z0 decays to b bbar g


  We have made the first direct symmetry tests in the decays of polarized Z0
bosons into fully-identified b bbar g states, collected in the SLD experiment
at SLAC. We searched for evidence of parity violation at the b bbar g vertex by
studying the asymmetries in the b-quark polar- and azimuthal-angle
distributions, and for evidence of T-odd, CP-even or odd, final-state
interactions by measuring angular correlations between the three-jet plane and
the Z0 polarization. We found results consistent with Standard Model
expectations, and set 95% C.L. limits on anomalous contributions.

</DOC>
<DOC>
<DOCNO> 122739 </DOCNO>
On the dependence of spectroscopic indices of early-type galaxies on


  We investigate the Mg-sigma and <Fe>-sigma relations in a sample of 72
early-type galaxies drawn mostly from cluster and group environments using a
homogeneous data-set which is well-calibrated onto the Lick/IDS system. The
small intrinsic scatter in Mg at a given sigma gives upper limits on the spread
in age and metallicity of 49% and 32% respectively, if the spread is attributed
to one quantity only and if the variations in age and metallicity are
uncorrelated. The age/metallicity distribution as inferred from the Hbeta vs
<Fe> diagnostic diagram reinforces this conclusion, as we find mostly galaxies
with large luminosity weighted ages spanning a range in metallicity. In our
sample we do not find significant evidence for an anti-correlation of ages and
metallicities which would keep the index-sigma relations tight while hiding a
large spread in age and metallicity. As a result of correlated errors in the
age-metallicity plane, a mild age-metallicity anti-correlation cannot be
completely ruled out given the current data. Correcting the line-strengths
indices for non-solar abundance ratios following the recent paper by Trager et
al., leads to higher mean metallicity and slightly younger age estimates while
preserving the metallicity sequence. The [Mg/Fe] ratio is mildly correlated
with the central velocity dispersion and ranges from [Mg/Fe]=0.05 to 0.3 for
galaxies with sigma > 100 km/s. Under the assumption that there is no age
gradient along the index-sigma relations, the abundance-ratio corrected
Mg-sigma, <Fe>-sigma and Hbeta-sigma relations give consistent estimates of
Delta [M/H]/ Delta log sigma = 0.9 (+- 0.1). The slope of the Hbeta-sigma
relation limits a potential age trend as a function of sigma to 2-3 Gyrs along
the sequence.(abriged)

</DOC>
<DOC>
<DOCNO> 170088 </DOCNO>
Time operator for the quantum harmonic oscillator: resolution of an


  An apparent paradox is resolved that concerns the existence of time operators
which have been derived for the quantum harmonic oscillator. There is an
apparent paradox because, although a time operator is canonically conjugate to
the Hamiltonian, it has been asserted that no operator exists that is
canonically conjugate to the Hamiltonian. In order to resolve the apparent
paradox, we work in a representation where the phase operator is diagonal. The
boundary condition on wave functions is such that they be periodic in the phase
variable, which is related to the (continuous) eigenvalue of the time operator.
Matrix elements of the commutator of the time operator with the Hamiltonian
involve the phase variable itself in addition to periodic functions of the
phase variable. The Hamiltonian is not hermitian when operating in space that
includes the phase variable itself. The apparent paradox is resolved when this
non-hermeticity is taken into account correctly in the evaluation of matrix
elements of the commutation relation.

</DOC>
<DOC>
<DOCNO> 10644 </DOCNO>
A generalized spherical version of the Blume-Emery-Griffits model with


  We have investigated analitycally the phase diagram of a generalized
spherical version of the Blume-Emery-Griffiths model that includes
ferromagnetic or antiferromagnetic spin interactions as well as quadrupole
interactions in zero and nonzero magnetic field. We show that in three
dimensions and zero magnetic field a regular paramagnetic-ferromagnetic (PM-FM)
or a paramagnetic-antiferromagnetic (PM-AFM) phase transition occurs whenever
the magnetic spin interactions dominate over the quadrupole interactions.
However, when spin and quadrupole interactions are important, there appears a
reentrant FM-PM or AFM-PM phase transition at low temperatures, in addition to
the regular PM-FM or PM-AFM phase transitions. On the other hand, in a nonzero
homogeneous external magnetic field $H$, we find no evidence of a transition to
the state with spontaneous magnetization for FM interactions in three
dimensions. Nonethelesss, for AFM interactions we do get a scenario similar to
that described above for zero external magnetic field, except that the critical
temperatures are now functions of $H$. We also find two critical field values,
$H_{c1}$, at which the reentrance phenomenon dissapears and $H_{c2}$
($H_{c1}\approx 0.5H_{c2}$), above which the PM-AFM transition temperature
vanishes.

</DOC>
<DOC>
<DOCNO> 7882 </DOCNO>
Phase Transition in the Takayasu Model with Desorption


  We study a lattice model where particles carrying different masses diffuse,
coalesce upon contact, and also unit masses adsorb to a site with rate $q$ or
desorb from a site with nonzero mass with rate $p$. In the limit $p=0$ (without
desorption), our model reduces to the well studied Takayasu model where the
steady-state single site mass distribution has a power law tail $P(m)\sim
m^{-\tau}$ for large mass. We show that varying the desorption rate $p$ induces
a nonequilibrium phase transition in all dimensions. For fixed $q$, there is a
critical $p_c(q)$ such that if $p<p_c(q)$, the steady state mass distribution,
$P(m)\sim m^{-\tau}$ for large $m$ as in the Takayasu case. For $p=p_c(q)$, we
find $P(m)\sim m^{-\tau_c}$ where $\tau_c$ is a new exponent, while for
$p>p_c(q)$, $P(m)\sim \exp(-m/m^*)$ for large $m$. The model is studied
analytically within a mean field theory and numerically in one dimension.

</DOC>
<DOC>
<DOCNO> 12013 </DOCNO>
Polarization rotation via a monoclinic phase in the piezoelectric


  The origin of ultrahigh piezoelectricity in the relaxor ferroelectric
PbZn1/3Nb2/3O3-PbTiO3 was studied with an electric field applied along the
[001] direction. The zero-field rhombohedral R phase starts to follow the
direct polarization path to tetragonal symmetry via an intermediate monoclinic
M phase, but then jumps irreversibly to an alternate path involving a different
type of monoclinic distortion. Details of the structure and domain
configuration of this novel phase are described. This result suggests that
there is a nearby R-M phase boundary as found in the Pb(Ti,Zr)O3 system.

</DOC>
<DOC>
<DOCNO> 117213 </DOCNO>
A linear radiofrequency ion trap for accumulation, bunching, and


  An ion beam cooler and buncher has been developed for the manipulation of
radioactive ion beams. The gas-filled linear radiofrequency ion trap system is
installed at the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. Its
purpose is to accumulate the 60-keV continuous ISOLDE ion beam with high
efficiency and to convert it into low-energy low-emittance ion pulses. The
efficiency was found to exceed 10% in agreement with simulations. A more than
10-fold reduction of the ISOLDE beam emittance can be achieved. The system has
been used successfully for first on-line experiments. Its principle, setup and
performance will be discussed.

</DOC>
<DOC>
<DOCNO> 71396 </DOCNO>
Neutron Stars with a Stable, Light Supersymmetric Baryon


  If a light gluino exists, the lightest gluino-containing baryon, the \OSO, is
a possible candidate for self-interacting dark matter. In this scenario, the
simplest explanation for the observed ratio $\Omega_{dm}/\Omega_b \approx 6-10$
is that $m_{S^0} \sim 900$\MeVcs; this is not at present excluded by particle
physics. Such an \OSO could be present in neutron stars, with hyperon formation
serving as an intermediate stage. We calculate equilibrium compositions and
equation of state for high density matter with the \OSO, and find that for a
wide range of parameters the properties of neutron stars with the \OSO are
consistent with observations. In particular, the maximum mass of a nonrotating
star is $1.7-1.8 M_\odot$, and the presence of the \OSO is helpful in
reconciling observed cooling rates with hyperon formation.

</DOC>
<DOC>
<DOCNO> 67995 </DOCNO>
Rapidity gaps at HERA and the Tevatron from soft colour exchanges


  Models based on soft colour exchanges to rearrange colour strings in the
final state provide a general framework for both diffractive and
non-diffractive events in ep and hadron-hadron collisions. We study two such
models and find that they can reproduce rapidity gap data from both HERA and
the Tevatron. We also discuss the influence of parton cascades and multiple
interactions on the results.

</DOC>
<DOC>
<DOCNO> 151320 </DOCNO>
Reparametrization-Invariant Path Integral in GR and "Big Bang" of


  The reparametrization-invariant generating functional for the unitary and
causal perturbation theory in general relativity in a finite space-time is
obtained. The region of validity of the Faddeev-Popov-DeWitt functional is
studied. It is shown that the invariant content of general relativity as a
constrained system can be covered by two "equivalent" unconstrained systems:
the "dynamic" (with "dynamic" evolution parameter as the metric scale factor)
and "geometric" (given by the Levi-Civita type canonical transformation to the
action-angle variables where the energy constraint converts into a new
momentum). "Big Bang", the Hubble evolution, and creation of matter fields by
the "geometric" vacuum are described by the inverted Levi-Civita (LC)
transformation of the geomeric system into the dynamic one. The particular case
of the LC transformations are the Bogoliubov ones of the particle variables
(diagonalizing the dynamic Hamiltonian) to the quasiparticles (diagonalizing
the equations of motion). The choice of initial conditions for the "Big Bang"
in the form of the Bogoliubov (squeezed) vacuum reproduces all stages of the
evolution of the Friedmann-Robertson-Walker Universe in their conformal
(Hoyle-Narlikar) versions.

</DOC>
<DOC>
<DOCNO> 122425 </DOCNO>
Evidence for compact structuring in the corona of active stars


  The ``current wisdom'' regarding the structuring of the X-ray emitting corona
in active stars (i.e. a corona dominated by extended coronal structures) is
briefly reviewed, followed by a review of a new approach to flare analysis and
the analysis of a significant number of newly observed and previously published
large flares, all leading to a much more compactly structured corona. Recent
observations showing the polar location of the flaring plasma are then
discussed, showing how the current evidence points toward a (flaring) corona
composed of rather low-lying polar structures, also in agreement with some
recent radio VLBI observational results and with starspot Doppler images. The
resulting picture is significantly different from the solar case.

</DOC>
<DOC>
<DOCNO> 120903 </DOCNO>
The ROSAT-ESO Flux Limited X-ray (REFLEX) Galaxy Cluster Survey II: The


  We report the results of the spatial two-point correlation function xi(r) for
the new X-ray galaxy cluster survey REFLEX, which comprises of 452 X-ray
selected clusters (449 with redshifts) detected by the ROSAT satellite during
the ROSAT All-Sky-Survey. The REFLEX cluster sample is flux limited to
3x10^{-12} erg s^{-1} cm^{-2} in the ROSAT energy band (0.1-2.4 keV) and spans
3 decades in X-ray luminosity (10^{42} - 10^{45} h^{-2} erg s^{-1}), containing
galaxy groups and rich clusters out to a redshift z~0.3. Covering a contiguous
area of 4.24 sr REFLEX is the largest X-ray cluster sample to date for which
spatial clustering has been analysed. Correlation studies using clusters
selected on the basis of their X-ray emission are particularly interesting as
they are largely free from the projection biases inherent to optical studies.
For the entire flux-limited sample we find that the correlation length (the
scale at which the correlation amplitude passes through unity) r_0~20
h^{-1}Mpc. For example, if a power-law fit is made to xi(r) over the range 4-40
h^{-1} Mpc then r_0=18.8+-0.9. An indication of the robustness of this result
comes from the high degree of isotropy seen in the clustering pattern on scales
close to the correlation length. On larger scales xi(r) deviates from a
power-law, crossing zero at ~45h^{-1} Mpc. From an examination of 5
volume-limited cluster sub-samples we find no significant trend of r_0 with
limiting X-ray luminosity. A comparison with recent model predictions for the
clustering properties of X-ray flux-limited samples, indicates that Cold Dark
Matter models with the matter density Omega_m=1 fail to produce sufficient
clustering to account for the data, while Omega_m~0.3 models provide an
excellent fit.

</DOC>
<DOC>
<DOCNO> 70239 </DOCNO>
Green's Functions in Axial and Lorentz-type Gauges and Application to


  We summarize the work done in connecting Green's functions in a different
classes of gauges and its applications to the problems in the axial gauges.The
procedure adopted uses finite field-dependent BRS [FFBRS] transformations to
connect axial and the Lorentz type gauges.These transformations preserve the
vacuum expectation of gauge-invariant observables explicitly. We discuss the
applications of these ideas to the axial gauge pole problem and to the
preservation of the Wilson loop and the thermal Wilson loop.

</DOC>
<DOC>
<DOCNO> 151204 </DOCNO>
Note on the dual BRST Symmetry in U(1) Gauge Theory


  We analyze the relation between the Lagrangian and Hamiltonian BRST symmetry
generators for a recently proposed two-dimensional symmetry. In particular it
is shown that this symmetry may be obtained from a canonical transformation in
the ghost sector in a gauge independent way.

</DOC>
<DOC>
<DOCNO> 122062 </DOCNO>
Starburst activity in a ROSAT Narrow Emission-Line Galaxy


  We present multiwaveband photometric and optical spectropolarimetric
observations of the R=15.9 narrow emission line galaxy R117_A which lies on the
edge of the error circle of the ROSAT X-ray source R117 (from McHardy et al
1998). The overall spectral energy distribution of the galaxy is well modelled
by a combination of a normal spiral galaxy and a moderate-strength burst of
star formation. The far infra-red and radio emission is extended along the
major axis of the galaxy, indicating an extended starburst.
  On positional grounds, the galaxy is a good candidate for the identification
of R117 and the observed X-ray flux is very close to what would be expected
from a starburst of the observed far infra-red and radio fluxes. Although an
obscured high redshift QSO cannot be entirely ruled out as contributing some
fraction of the X-ray flux, we find no candidates to K=20.8 within the X-ray
errorbox and so conclude that R117_A is responsible for a large fraction, if
not all, of the X-ray emission from R117.
  Searches for indicators of an obscured AGN in R117_A have so far proven
negative; deep spectropolarimetric observations show no signs of broad lines to
a limit of one per cent and, for the observed far infra-red and radio emission,
we would expect a ten times greater X-ray flux if the overall emission were
powered by an AGN. We therefore conclude that the X-ray emission from R117 is
dominated by starburst emission from the galaxy R117_A.

</DOC>
<DOC>
<DOCNO> 7911 </DOCNO>
A Method to Calculate a Delta Function of the Hamiltonian by the


  We propose a new method to calculate expectation values of a delta function
of the Hamiltonian, < \Psi \mid \delta(\hat{H} - E)\mid \Psi >. Since the delta
function can be replaced with a Gaussian function, we evaluate < \Psi \mid
\sqrt{\frac{\beta}{\pi}} e^{-\beta (\hat{H} - E)^2} \mid \Psi > with large
\beta adopting the Suzuki-Trotter decomposition. Errors of the approximate
calculations with the finite Trotter number N_t are estimated to be O(1/N_t^K)
for the Kth-order decomposition. The distinct advantage of this method is that
the convergence is guaranteed even when the state \mid \Psi > contains the
eigenstates whose energies spread over the wide range. In this paper we give a
full description of our method within the quantum mechanical physics and
present the numerical results for the harmonic oscillator problems in one- and
three-dimensional space.

</DOC>
<DOC>
<DOCNO> 7638 </DOCNO>
Effect of doping on the linear temperature dependence of the magnetic


  We report on measurements of the low temperature dependence of the magnetic
penetration depth lambda_ab in several single crystals of La_2-xSr_xCuO_4,
Bi_2Sr_2CaCu_2O_8 and YBa_2Cu_3O_6+x at various doping levels ranging from the
under- to the overdoped regimes by using a novel single-coil technique
achieving 10 pm resolution. We have found a linear dependence of lambda_ab in
all samples with a rapidly increasing slope dlambda_ab/dT as doping decreases.
Our analysis of the data indicates that a superconducting gap with d-wave
symmetry is sufficient to quantitatively account for the above slope values in
the optimally or over- doped samples. In the underdoped samples, the d-wave
model predicts much smaller values than those measured by assuming realistic
values for the zero-temperature lambda_ab and gap delta. The experimental data
are compatible with a model of thermodynamic phase fluctuations of the order
parameter. Therefore, we put forward the hypothesis that the gapless properties
observed in cuprates may have qualitatively different physical origins
depending on the doping level.

</DOC>
<DOC>
<DOCNO> 170383 </DOCNO>
NMR Quantum Computation


  In this article I will describe how NMR techniques may be used to build
simple quantum information processing devices, such as small quantum computers,
and show how these techniques are related to more conventional NMR experiments.

</DOC>
<DOC>
<DOCNO> 80689 </DOCNO>
Perturbative renormalization of the first two moments of non-singlet


  Using the overlap-Dirac operator proposed by Neuberger, we have computed in
lattice QCD the one-loop renormalization factors of ten operators which measure
the lowest two moments of unpolarized and polarized non-singlet quark
distributions. These factors are necessary to extract physical numbers from
Monte Carlo simulations made with overlap fermions.
  An exact chiral symmetry is maintained in all our results, and the
renormalization constants of corresponding unpolarized and polarized operators
which differ by a $\gamma_5$ matrix have the same value. We have considered two
lattice representations for each continuum operator. The computations have been
carried out using the symbolic language FORM, in a general covariant gauge. In
some simple cases they have also been checked by hand.

</DOC>
<DOC>
<DOCNO> 99671 </DOCNO>
Noncommutative differential calculus, homotopy BV algebras and formality


  We define a notion of astrongly homotopy BV algebra and apply it to
deformation theory problems. Formality conjectures for Hochschild and cyclic
chains are formulated. We prove some partial results supporting these
conjectures.

</DOC>
<DOC>
<DOCNO> 68747 </DOCNO>
Binding energy corrections in positronium decays


  Positronium annihilation amplitudes that are computed by assuming a
factorization approximation with on-shell intermediate leptons, do not exhibit
good analytical behavior. We propose an ansatz which allows to include binding
energy corrections and obtain the correct analytical and gauge invariance
behavior of these QED amplitudes. As a consequence of these non-perturbative
corrections, the parapositronium and orthopositronium decay rates receive
corrections of order alpha^4 and alpha^2, respectively. These new corrections
for orthopositronium are relevant in view of a precise comparison between
recent theoretical and experimental developments. Implications are pointed out
for analogous decays of quarkonia .

</DOC>
<DOC>
<DOCNO> 13428 </DOCNO>
Second Law of Thermodynamics and Macroscopic Observables within


  Boltzmann's principleS=k*ln W is generalized to non-equilibrium Hamiltonian
systems with possibly fractal distributions in phase space by the box-counting
volume. The probabilities P(M) of macroscopic observables M are given by the
ratio P(M)=W(M)/W of these volumes of the sub-manifold {M} of the
microcanonical ensemble with the constraint M to the one without. With this
extension of the phase-space integral the Second Law is derived without
invoking the thermodynamic limit. The irreversibility in this approach is due
to the replacement of the phase space volume of the possibly fractal
sub-manifold {M} by the volume of the closure of {M}. In contrast to
conventional coarse graining the box-counting volume is defined by the limit of
infinite resolution.

</DOC>
<DOC>
<DOCNO> 178453 </DOCNO>
Quark Substructure and Isobar Effects on Deuteron Form-Factors


  Elastic ed scattering, with deuteron polarization, up to high momentum
transfer provides detailed information on the deuteron wave function. This
determines the range dependence of the orbital and spin components of the one-
and two-body currents, restricting contributions of isobar and meson-exchange
currents and of quark/gluon degrees of freedom, as well as the nucleon
component. The R-matrix boundary condition model combines all these effects,
predicting nucleon-nucleon reactions and the deuteron form-factors
simultaneously. A brief description of the model is followed by a comparison of
its results with data, emphasizing the restrictions placed on the model by ed
elastic form-factors.

</DOC>
<DOC>
<DOCNO> 85227 </DOCNO>
Particle Creation in Pre-Big-Bang Cosmology: theory and observational


  We present some phenomenological aspects of the pre-big-bang cosmological
model inspired by the duality properties of string theory. In particular,
assuming the spatial sections of the homogeneous background geometry to be
isotropic, we discuss the quantum production of perturbations of the background
fields (gravitons, dilatons, moduli fields), as well as the production of
particles which do not contribute to the background, which we call ``seeds''.
As such we consider the cases of electromagnetic and axionic seeds. We also
discuss their possible observational consequences, for example, we study
whether they can provide the origin of primordial galactic magnetic fields, and
whether they can generate the initial fluctuations leading to the formation of
large-scale structure and the measured cosmic microwave background
anisotropies. We finally analyze axion and photon production in four
dimensional anisotropic pre-big-bang cosmological models.

</DOC>
<DOC>
<DOCNO> 117863 </DOCNO>
Spin-Orbit Couplings in X-ray Binaries


  We discuss the influence of tidal spin-orbit interactions on the orbital
dynamics of close intermediate-mass X-ray binaries. In particular we consider
here a process in which spin angular momentum of a contracting RLO donor star,
in a synchronous orbit, is converted into orbital angular momentum and thus
helps to stabilize the mass transfer by widening the orbit. Binaries which
would otherwise suffer from dynamically unstable mass transfer (leading to the
formation of a common envelope and spiral-in evolution) are thus shown to
survive a phase of extreme mass transfer on a sub-thermal timescale.
Furthermore, we discuss the orbital evolution prior to RLO in X-ray binaries
with low-mass donors, caused by the competing effects of wind mass loss and
tidal effects due to expansion of the (sub)giant.

</DOC>
<DOC>
<DOCNO> 10304 </DOCNO>
Market Ecology, Pareto Wealth Distribution and Leptokurtic Returns in


  The LLS stock market model is a model of heterogeneous quasi-rational
investors operating in a complex environment about which they have incomplete
information. We review the main features of this model and several of its
extensions. We study the effects of investor heterogeneity and show that
predation, competition, or symbiosis may occur between different investor
populations. The dynamics of the LLS model lead to the empirically observed
Pareto wealth distribution. Many properties observed in actual markets appear
as natural consequences of the LLS dynamics: truncated Levy distribution of
short-term returns, excess volatility, a return autocorrelation "U-shape"
pattern, and a positive correlation between volume and absolute returns.

</DOC>
<DOC>
<DOCNO> 178615 </DOCNO>
Transition Strength Sums and Quantum Chaos in Shell Model States


  For the embedded Gaussian orthogonal ensemble (EGOE) of random matrices, the
strength sums generated by a transition operator acting on an eigenstate vary
with the excitation energy as the ratio of two Gaussians. This general result
is compared to exact shell model calculations, with realistic interactions, of
spherical orbit occupancies and Gamow-Teller strength sums in some $(ds)$ and
$(fp)$ shell examples. In order to confirm that EGOE operates in the chaotic
domain of the shell model spectrum, calculations are carried out using two
different interpolating hamiltonians generating order-chaos transitions. Good
agreement is obtained in the chaotic domain of the spectrum, and strong
deviations are observed as nuclear motion approaches a regular regime
(transition strength sums appear to follow the Dyson's $\Delta_3$ statistic).
More importantly, they shed new light on the newly emerging understanding that
in the chaotic domain of isolated finite interacting many particle systems
smoothed densities (they include strength functions) define the statistical
description of these systems and these densities follow from embedded random
matrix ensembles; some EGOE calculations to this end are presented.

</DOC>
<DOC>
<DOCNO> 170001 </DOCNO>
Comment on "Experimental realization of Popper's experiment: Violation


  Application of the uncertainty principle to conditional measurements is
investigated, and found to be valid for measurements on separated sub-systems.
In light of this, an apparent violation of the uncertainty principle obtained
by Kim and Shih in their realization of Popper's experiment (quant-ph/9905039)
is explained through analogy with a simple optical system.

</DOC>
<DOC>
<DOCNO> 85612 </DOCNO>
Quantum fields on timelike curves


  A quantum field F(x) exists at an event x of space-time in general only as a
quadratic form. Only after smearing with a smooth test function we get an
operator. In this paper the question is considered whether it is possible as
well to smear F(x) with a singular test function T (i.e. a test distribution)
supported by a smooth timelike curve. It is shown that this is always possible
if F(x) satisfies the micro local spectrum condition and T belongs to a special
class of distributions which retain some regularity in timelike directions. In
the free field case these results are used to define some kind of
time-translation along the curve which generalizes global space-time
translations of Minkowski space.

</DOC>
<DOC>
<DOCNO> 69956 </DOCNO>
Pi0 -> Gamma Gamma in Dense QCD


  QCD superconductors in the color-flavor-locked (CFL) phase support light
excitations (generalized pions) in the form of particle-particle or hole-hole
excitations. We analyze the generalized process
$\tilde\pi^0\to\tilde{\gamma}\tilde{\gamma}$ in the weak coupling limit and
show that it is related to the recently suggested Wess-Zumino-Witten (WZW)
term. In dense QCD, the radiative decay of the generalized pion is constrained
by geometry and vanishes at large density.

</DOC>
<DOC>
<DOCNO> 85190 </DOCNO>
Creation of superheavy particles in Friedmann cosmology and the dark


  The model of creation of observable particles and particles of the dark
matter, considered to be superheavy particles, due to particle creation by the
gravitational field of the Friedmann model of the early Universe is given.
Estimates on the parameters of the model leading to observable values of the
baryon number of the Universe and the dark matter density are made.

</DOC>
<DOC>
<DOCNO> 39721 </DOCNO>
Detection of very small neutrino masses in double-beta decay using laser


  We describe an approach to the study of neutrino masses that combines quantum
optics techniques with radiation detectors to obtain unprecedented sensitivity.
With it the search for Majorana neutrino masses down to $\sim$10 meV will
become accessible. The experimental technique uses the possibility of
individually detecting $\rm Ba^+$-ions in the final state of $\rm ^{136}Xe$
double-beta decay via resonant excitation with a set of lasers aimed at a
specific location in a large Time Projection Chamber. The specificity of the
atomic levels provides tagging and, together with more traditional event
recognition parameters, greatly suppresses radioactive backgrounds.

</DOC>
<DOC>
<DOCNO> 71823 </DOCNO>
TASI Lectures: Cosmology for String Theorists


  These notes provide a brief introduction to modern cosmology, focusing
primarily on theoretical issues. Some attention is paid to aspects of potential
interest to students of string theory, on both sides of the two-way street of
cosmological constraints on string theory and stringy contributions to
cosmology. Slightly updated version of lectures at the 1999 Theoretical
Advanced Study Institute at the University of Colorado, Boulder.

</DOC>
<DOC>
<DOCNO> 10612 </DOCNO>
Field induced long-range-ordering in an S=1 quasi-one-dimensional


  We have measured the heat capacity and magnetization of the spin one
one-dimensional Heisenberg antiferromagnet NDMAP and constructed a magnetic
field versus temperature phase diagram. We found a field induced long-range
magnetic ordering. We have been successful in explaining the phase diagram
theoretically.

</DOC>
<DOC>
<DOCNO> 12702 </DOCNO>
Metal insulator transition in TlSr2CoO5 from orbital degeneracy and spin


  To describe the metal insulator transition in the new oxide TlSr2CoO5 we
investigate its electronic structure by LDA and model Hartree-Fock
calculations. Within LDA we find a homogeneous metallic and ferromagnetic
ground state, but when including the Coulomb interaction more explicitly within
the Hartree-Fock approximation, we find an insulating state of lower energy
with both spin and orbital order. We also interpret our results in terms of a
simple model.

</DOC>
<DOC>
<DOCNO> 9156 </DOCNO>
Interface Scaling in the Contact Process


  Scaling properties of an interface representation of the critical contact
process are studied in dimensions 1 - 3. Simulations confirm the scaling
relation beta_W = 1 - theta between the interface-width growth exponent beta_W
and the exponent theta governing the decay of the order parameter. A scaling
property of the height distribution, which serves as the basis for this
relation, is also verified. The height-height correlation function shows clear
signs of anomalous scaling, in accord with Lopez' analysis [Phys. Rev. Lett.
83, 4594 (1999)], but no evidence of multiscaling.

</DOC>
<DOC>
<DOCNO> 123091 </DOCNO>
A radio supernova remnant associated with the young pulsar J1119-6127


  We report on Australia Telescope Compact Array observations in the direction
of the young high magnetic-field pulsar J1119-6127. In the resulting images we
identify a non-thermal radio shell of diameter 15', which we classify as a
previously uncatalogued young supernova remnant, G292.2-0.5. This supernova
remnant is positionally coincident with PSR J1119-6127, and we conclude that
the two objects are physically associated. No radio emission is detected from
any pulsar wind nebula (PWN) associated with the pulsar; our observed upper
limits are consistent with the expectation that high magnetic-field pulsars
produce radio nebulae which fade rapidly. This system suggests a possible
explanation for the lack of an associated radio pulsar and/or PWN in many
supernova remnants.

</DOC>
<DOC>
<DOCNO> 121390 </DOCNO>
Infrared Spectra of Cooling Flow Galaxies


  We have taken K-band spectra covering 7 cooling flow clusters. The spectra
show many of the 1-0S transitions of molecular Hydrogen, as well as some of the
higher vibrational transitions, and some lines of ionized Hydrogen. The line
ratios allow us to conclude that the rotational states of the first excited
vibrational state are in approximate LTE, so that densities above 10^5/ cm^3
are likely, but there is evidence that the higher vibrational states are not in
LTE. The lack of pressure balance between the molecular gas and the ionized
components emphasizes the need for dynamic models of the gas. The ratios of the
ionized to molecular lines are relatively constant but lower than from
starburst regions, indicating that alternative heating mechanisms are
necessary.

</DOC>
<DOC>
<DOCNO> 118831 </DOCNO>
Hotspot Emission from a Freely Precessing Neutron Star


  Recent observations of 1E~161348-5055, the neutron-star candidate at the
center of the supernova remnant RCW 103, show that a component of its emission
varies sinusoidally with a period of approximately six hours. We argue that
this period is what one would expect for a freely precessing neutron star with
a spin period of about one second. We produce light curves for a freely
precessing neutron star with a hotspot. By a suitable choice of parameters, we
obtain light curves which are constant with rotational phase when the flux from
the star reaches a maximum. At other phases of the precession, the flux varies
as the star rotates but the total flux decreases by a factor of several. These
models can explain the behavior observed from 1E~161348-5055 and predict that
the spin period should be detectable at minimum flux from sufficiently
sensitive measurements.

</DOC>
<DOC>
<DOCNO> 123048 </DOCNO>
The Optical Spectroscopic Evolution of V1974 Cygni (Nova Cygni 1992)


  Optical observations of nova V1974 Cygni (Cygni 1992), spanning a 4 year
period, have been used to study its spectroscopic evolution. The data cover a
wavelength range from $\sim 3200 - 8000$ \AA and follows the nebular
evolutionary phase of the ejecta. We have modeled the integrated fluxes by
means of the photoionization code CLOUDY. The models were run at a {\it fixed}
abundance value for the most prominent elements (i.e. H, He, C, O, N, Ne, Fe,
etc) over the entire time sequence. It is possible to constrain from this
simple model some of the physical conditions of the gaseous emitting region,
like temperature and density. Compared with previous studies of the gas
abundances of the heavy elements, we found that smaller enhancements of S, N
and Ar, and comparable values for O and Fe, are able to reproduce the
observations. The time evolution of the surface temperature of the ionizing
source and the high-ionization iron lines [Fe VII] 6087 \AA and [Fe X] 6374
\AA, is similar to what it is observed in the soft X-rays. The early line
profiles can be reproduced using a simple kinematical model consisting of an
equatorial ring and polar caps, expanding at a velocity of $\sim 1100$ km/s.
This simple model also approximates the structure of the resolved shell
observed by HST. Considering the complicated structure of the shell, the lack
of well defined values of its gas density and our limited knowledge of the time
evolution of the surface temperature of the photoionization source, the
comparison between models and observations agrees remarkably well.

</DOC>
<DOC>
<DOCNO> 84697 </DOCNO>
Higher regularity properties of mappings and morphisms


  We propose to extend ``invertibility'' to ``regularity'' for categories in
general abstract algebraic manner. Higher regularity conditions and
``semicommutative'' diagrams are introduced. Distinction between commutative
and ``semicommutative'' cases is measured by non-zero obstruction proportional
to the difference of some self-mappings (obstructors) $e^{(n)}$ from the
identity. This allows us to generalize the notion of functor and to
``regularize'' braidings and related structures in monoidal categories. A
``noninvertible'' analog of the Yang-Baxter equation is proposed.

</DOC>
<DOC>
<DOCNO> 118087 </DOCNO>
Lyapunov exponent in quantum mechanics. A phase-space approach


  Using the symplectic tomography map, both for the probability distributions
in classical phase space and for the Wigner functions of its quantum
counterpart, we discuss a notion of Lyapunov exponent for quantum dynamics.
Because the marginal distributions, obtained by the tomography map, are always
well defined probabilities, the correspondence between classical and quantum
notions is very clear. Then we also obtain the corresponding expressions in
Hilbert space. Some examples are worked out. Classical and quantum exponents
are seen to coincide for local and non-local time-dependent quadratic
potentials. For non-quadratic potentials classical and quantum exponents are
different and some insight is obtained on the taming effect of quantum
mechanics on classical chaos. A detailed analysis is made for the standard map.
Providing an unambiguous extension of the notion of Lyapunov exponent to
quantum mechnics, the method that is developed is also computationally
efficient in obtaining analytical results for the Lyapunov exponent, both
classical and quantum.

</DOC>
<DOC>
<DOCNO> 10317 </DOCNO>
Self Consistent Field Theory of Twist Grain Boundaries in Block


  We apply self consistent field theory to twist grain boundaries of block
copolymer melts. The distribution of monomers throughout the grain boundary is
obtained as well as the grain boundary free energy per unit area as a function
of twist angle. We define an intermaterial dividing surface in order to compare
it with minimal surfaces which have been proposed. Our calculation shows that
the dividing surface is not a minimal one, but the linear stack of dislocations
seems to be a better representation of it for most angles than is Scherck's
first surface.

</DOC>
<DOC>
<DOCNO> 8832 </DOCNO>
Roughening and superroughening in the ordered and random two-dimensional


  We present a comparative numerical study of the ordered and the random
two-dimensional sine-Gordon models on a lattice. We analytically compute the
main features of the expected high temperature phase of both models, described
by the Edwards-Wilkinson equation. We then use those results to locate the
transition temperatures of both models in our Langevin dynamics simulations. We
show that our results reconcile previous contradictory numerical works
concerning the superroughening transition in the random sine-Gordon model. We
also find evidence supporting the existence of two different low temperature
phases for the disordered model. We discuss our results in view of the
different analytical predictions available and comment on the nature of these
two putative phases.

</DOC>
<DOC>
<DOCNO> 118334 </DOCNO>
Cooling curves and initial models for low-mass white dwarfs (<0.25 Msun)


  We present a detailed calculation of the evolution of low-mass ($<
0.25~M_\odot $) helium white dwarfs. These white dwarfs (the optical companions
to binary millisecond pulsars) are formed via long-term, low-mass binary
evolution. After detachment from the Roche lobe, the hot helium cores have a
rather thick hydrogen layer with mass between 0.01 to 0.06$~M_\odot $. Due to
mixing between the core and outer envelope, the surface hydrogen content is 0.5
to 0.35, depending on the initial value of the heavy element (Z) and the
initial secondary mass. We found that the majority of our computed models
experience one or two hydrogen shell flashes. We found that the mass of the
helium dwarf in which the hydrogen shell flash occurs depends on the chemical
composition. The minimum helium white dwarf mass in which a hydrogen flash
takes place is 0.213$~M_\odot $ (Z=0.003), 0.198$~M_\odot $ (Z=0.01),
0.192$~M_\odot $ (Z=0.02) or 0.183$~M_\odot $ (Z=0.03). The duration of the
flashes (independent of chemical composition) is between few $\times 10^6 $
years to few $\times 10^7 $ years. In several flashes the white dwarf radius
will increase so much that it forces the model to fill its Roche lobe again.
Our calculations show that cooling history of the helium white dwarf depends
dramatically on the thickness of the hydrogen layer. We show that the
transition from a cooling white dwarf with a temporary stable hydrogen-burning
shell to a cooling white dwarf in which almost all residual hydrogen is lost in
a few thermal flashes (via Roche-lobe overflow) occurs between
0.183-0.213$~M_\odot $ (depending on the heavy element value).

</DOC>
<DOC>
<DOCNO> 40030 </DOCNO>
Averaging Measurements with Hidden Correlations and Asymmetric Errors


  Properties of weighted averages are studied for the general case that the
individual measurements are subject to hidden correlations and have asymmetric
statistical as well as systematic errors. Explicit expressions are derived for
an unbiased average with a well defined error estimate.

</DOC>
<DOC>
<DOCNO> 150879 </DOCNO>
A Note on Classical Solution of Chaplygin-gas as D-brane


  The classical solution of bosonic d-brane in (d+1,1) space-time is studied.
We work with light-cone gauge and reduce the problem into Chaplygin gas
problem. The static equation is equivalent to vanishing of extrinsic mean
curvature, which is similar to Einstein equation in vacuum. We show that the
d-brane problem in this gauge is closely related to Plateau problem, and we
give some non-trivial solutions from minimal surfaces. The solutions of
d-1,d,d+1 spatial dimensions are obtained from d-dimensional minimal surfaces
as solutions of Plateau problem. In addition we discuss on the relation to
Hamiltonian-BRST formalism for d-branes.

</DOC>
<DOC>
<DOCNO> 68976 </DOCNO>
Jets and produced particles in pp collisions from SPS to RHIC energies


  Higher-order pQCD corrections play an important role in the reproduction of
data at high transverse momenta in the energy range 20 GeV $ \leq \sqrt{s} \leq
200$ GeV. Recent calculations of photon and pion production in $pp$ collisions
yield detailed information on the next-to-leading order contributions. However,
the application of these results in proton-nucleus and nucleus-nucleus
collisions is not straightforward. The study of nuclear effects requires a
simplified understanding of the output of these computations. Here we summarize
our analysis of recent calculations, aimed at handling the NLO results by
introducing process and energy-dependent $K$ factors.

</DOC>
<DOC>
<DOCNO> 178534 </DOCNO>
Particles in classically forbidden area, neutron skin and halo, and pure


  The nucleon density distributions and the thickness of pure neutron matter in
Ca isotopes were systematically studied using the Skyrme-Hartree-Fock model
(SHF) from the $\beta$-stability line to the neutron drip-line. The pure
neutron matter, related with the neutron skin or halo, was shown to depend not
only on the Fermi levels of the neutrons but also on the orbital angular
momentum of the valence neutrons. New definitions for the thickness of pure
neutron matter are proposed.

</DOC>
<DOC>
<DOCNO> 71064 </DOCNO>
Analysis of Long-Lived Slepton NLSP in GMSB model at Linear Collider


  We performed an analysis on the detection of a long-lived slepton at a linear
collider with $\sqrt{s}=500$ GeV. In GMSB models a long-lived NLSP is predicted
for large value of the supersymmetry breaking scale $\sqrt{F}$. Furthermore in
a large portion of the parameter space this particle is a stau. Such heavy
charged particles will leave a track in the tracking volume and hit the muonic
detector. In order to disentangle this signal from the muon background, we
explore kinematics and particle identification tools: time of flight device,
dE/dX and Cerenkov devices. We show that a linear collider will be able to
detect long-lived staus with masses up to the kinematical limit of the machine.
We also present our estimation of the sensitivity to the stau lifetime.

</DOC>
<DOC>
<DOCNO> 122380 </DOCNO>
The formation of cosmic structure with modified Newtonian dynamics


  I consider the growth of inhomogeneities in a low-density baryonic, vacuum
energy-dominated universe in the context of modified Newtonian dynamics (MOND).
I first write down a two-field Langrangian-based theory of MOND
(non-relativistic), which embodies several assumptions such as constancy of the
MOND acceleration parameter, association of a MOND force with peculiar
accelerations only, and the deceleration of the Hubble flow as a background
field which influences the dynamics of a finite size region. In the context of
this theory, the equation for the evolution of spherically symmetric
over-densities is non-linear and implies very rapid growth even in a
low-density background, particularly at the epoch when the putative
cosmological constant begins to dominate the Hubble expansion. Small comoving
scales enter the MOND regime earlier than larger scales and therefore evolve to
large over-densities sooner. Taking the initial COBE-normalized power spectrum
provided by CMBFAST (Seljak & Zeldarriaga 1996), I find that the final
power-spectrum resembles that of the standard LCDM universe and thus retains
the empirical successes of that model.

</DOC>
<DOC>
<DOCNO> 170425 </DOCNO>
Natural Thermal and Magnetic Entanglement in 1D Heisenberg Model


  We investigate the entanglement between any two spins in a one dimensional
Heisenberg chain as a function of temperature and the external magnetic field.
We find that the entanglement in an antiferromagnetic chain can be increased by
increasing the temperature or the external field. Increasing the field can also
create entanglement between otherwise disentangled spins. This entanglement can
be confirmed by testing Bell's inequalities involving any two spins in the
solid.

</DOC>
<DOC>
<DOCNO> 101846 </DOCNO>
RTT relations, a modified braid equation and noncommutative planes


  With the known group relations for the elements $(a,b,c,d)$ of a quantum
matrix $T$ as input a general solution of the $RTT$ relations is sought without
imposing the Yang - Baxter constraint for $R$ or the braid equation for
$\hat{R} = PR$. For three biparametric deformatios, $GL_{(p,q)}(2),
GL_{(g,h)}(2)$ and $GL_{(q,h)}(1/1)$, the standard,the nonstandard and the
hybrid one respectively, $R$ or $\hat{R}$ is found to depend, apart from the
two parameters defining the deformation in question, on an extra free parameter
$K$,such that only for two values of $K$, given explicitly for each case, one
has the braid equation. Arbitray $K$ corresponds to a class (conserving the
group relations independent of $K$) of the MQYBE or modified quantum YB
equations studied by Gerstenhaber, Giaquinto and Schak. Various properties of
the triparametric $\hat{R}(K;p,q)$, $\hat{R}(K;g,h)$ and $\hat{R}(K;q,h)$ are
studied. In the larger space of the modified braid equation (MBE) even
$\hat{R}(K;p,q)$ can satisfy $\hat{R}^2 = 1$ outside braid equation (BE)
subspace. A generalized, $K$- dependent, Hecke condition is satisfied by each
3-parameter $\hat{R}$. The role of $K$ in noncommutative geometries of the
$(K;p,q)$,$(K;g,h)$ and $(K;q,h)$ deformed planes is studied. K is found to
introduce a "soft symmetry breaking", preserving most interesting properties
and leading to new interesting ones. Further aspects to be explored are
indicated.

</DOC>
<DOC>
<DOCNO> 72110 </DOCNO>
gamma-gamma Interactions from Real to Virtual Photons


  A `complete' framework for gamma-gamma / gamma*-gamma / gamma*-gamma*
interactions is presented. The emphasis is on providing a model for gamma-gamma
physics at all photon virtualities, including the difficult transition region
around the rho meson mass.

</DOC>
<DOC>
<DOCNO> 117279 </DOCNO>
Electric Charge as a Vector Quantity


  Starting with the premise that the electric charge associated with
fundamental fermions (quarks and leptons) can, under certain circumstances, be
appropriately represented as a real \emph{internal} 2-vector, the mathematical
``machinery'' implicit in the associated internal 2-space is shown to apply to
\emph{all} fundamental fermions. In particular, it is shown that \emph{flavor
eigenstates}, \emph{flavor doublets} and \emph{families} of fundamental
fermions can all be represented in the 2-space, and that such things as
internal \emph{colors}, \emph{family replication}, and the observed
\emph{number} (three) of families, are more-or-less implicit in the new 2-space
description. Moreover, the model predicts that, unlike the case in the standard
model, particles such as the $u$, $c$ and $t$ quarks are characterized by
significant internal (topological and other) differences. Similar differences
may help explain recent observations of (nearly) maximal $\nu_{\mu}-\nu_{\tau}$
mixing.

</DOC>
<DOC>
<DOCNO> 84723 </DOCNO>
Quantum Geometry of Isolated Horizons and Black Hole Entropy


  Using the earlier developed classical Hamiltonian framework as the point of
departure, we carry out a non-perturbative quantization of the sector of
general relativity, coupled to matter, admitting non-rotating isolated horizons
as inner boundaries. The emphasis is on the quantum geometry of the horizon.
Polymer excitations of the bulk quantum geometry pierce the horizon endowing it
with area. The intrinsic geometry of the horizon is then described by the
quantum Chern-Simons theory of a U(1) connection on a punctured 2-sphere, the
horizon. Subtle mathematical features of the quantum Chern-Simons theory turn
out to be important for the existence of a coherent quantum theory of the
horizon geometry. Heuristically, the intrinsic geometry is flat everywhere
except at the punctures. The distributional curvature of the U(1) connection at
the punctures gives rise to quantized deficit angles which account for the
overall curvature. For macroscopic black holes, the logarithm of the number of
these horizon microstates is proportional to the area, irrespective of the
values of (non-gravitational) charges. Thus, the black hole entropy can be
accounted for entirely by the quantum states of the horizon geometry. Our
analysis is applicable to all non-rotating black holes, including the
astrophysically interesting ones which are very far from extremality.
Furthermore, cosmological horizons (to which statistical mechanical
considerations are known to apply) are naturally incorporated. An effort has
been made to make the paper self-contained by including short reviews of the
background material.

</DOC>
<DOC>
<DOCNO> 120217 </DOCNO>
Massive Star Forming Regions: from diagnostic tools to derived


  The current state-of-the-art of multi-wavelength diagnostic tools
(evolutionary synthesis, photoionisation models) for massive star forming
regions (HII regions, starbursts, etc.) and some of their input physics
(especially model atmospheres) is reviewed. Analysis of stellar populations
based on integrated spectra from both stellar features and nebular emission
lines from the UV to IR are summarised. We stress the importance of "template"
studies at various scales (from individual stars to well studied galaxies) and
various wavelengths, to understand the processes operating in massive star
forming regions and to reliably derive their properties.

</DOC>
<DOC>
<DOCNO> 116798 </DOCNO>
Suggestion for a Fast Heuristic for the Hamiltonian Cycle Problem


  Some years ago I demonstrated a simulated annealing heuristic for the
Hamiltonian cycle problem (Science 273, 413 (1996)). Here I propose an improved
version of this heuristic.

</DOC>
<DOC>
<DOCNO> 80906 </DOCNO>
Leptonic and semi-leptonic B decays


  We present results for the semi-leptonic and leptonic decays of B mesons.
These non-perturbative matrix elements are important for constraining the CKM
matrix. Results are presented for the pseudoscalar and vector decay constants,
as well as flavour breaking ratios and heavy quark symmetry relations. We
consider the chiral and momentum dependence of the semi-leptonic form factors
of the decay B-> pi l nu and the soft pion relation (SPR) on the lattice. These
calculations were performed in the quenched approximation at two values of the
coupling with non-perturbatively order a improved action and currents.

</DOC>
<DOC>
<DOCNO> 80825 </DOCNO>
On the continuum limit of fermionic topological charge in lattice gauge


  It is proved that the fermionic topological charge of SU(N) lattice gauge
fields on the 4-torus, given in terms of a spectral flow of the Hermitian
Wilson--Dirac operator, or equivalently, as the index of the Overlap Dirac
operator, reduces to the continuum topological charge in the classical
continuum limit when the parameter $m_0$ is in the physical region $0<m_0<2$.

</DOC>
<DOC>
<DOCNO> 119657 </DOCNO>
Cosmic Microwave Background Temperature at 1280 MHz


  The absolute temperature of the cosmic microwave background (CMB) has been
measured at a frequency of 1280 MHz. The observation was made with a modified
version of the L-band receiver used in the Giant Metre wavelength Radio
Telescope (GMRT): the feed horn was replaced by a corrugated plate and the
receiver was placed on the ground, directed at zenith, and shielded from ground
radiation by an aluminium screen with corrugated edges. Novel techniques have
been adopted for (1) reducing and cancelling unwanted contributions to the
system temperature of the receiver and (2) calibrating the contributions from
the feed assembly and receiver. The thermodynamic temperature of the CMB is
estimated to be 3.45 +/- 0.78 K.

</DOC>
<DOC>
<DOCNO> 71657 </DOCNO>
Single particle strength restoration and nuclear transparency in high


  Quenching of the single particle strength which previously precluded
unambiguous measurement of nuclear transparency in quasifree (e,e'p) reactions
at high momentum transfer is evaluated from the cross sections of measured
processes. We have demonstrated evidence of the single particle strength
restoration with increase of the momentum transfer in exclusive (e,e'p)
reactions and argue that in practically interesting cases of study the nuclear
transparency in these processes quenching is weakly depends on the probability
of short range nucleon correlations. It is shown that use of Glauber
approximation well describes NE18 and E94-139 (e,e'p) data at the momentum
transfers 1 GeV^2 < Q^2 < 3 GeV^2. This gives a further support to our
observation that the quenching of nuclear levels strongly depends on the
resolution (Q^2)and practically disappears at Q^2>1GeV^2.

</DOC>
<DOC>
<DOCNO> 8023 </DOCNO>
T=0 Partition Functions for Potts Antiferromagnets on Square Lattice


  We present exact calculations of the zero-temperature partition function for
the q-state Potts antiferromagnet (equivalently, the chromatic polynomial) for
two families of arbitrarily long strip graphs of the square lattice with
periodic boundary conditions in the transverse direction and (i) periodic (ii)
twisted periodic boundary conditions in the longitudinal direction, so that the
strip graphs are embedded on a (i) torus (ii) Klein bottle. In the limit of
infinite length, we calculate the exponent of the entropy, W(q), show it to be
the same for (i) and (ii), and determine its analytic structure.

</DOC>
<DOC>
<DOCNO> 99757 </DOCNO>
Some measure-preserving point transformations on the Wiener space and


  Suppose that T is a map of the Wiener space into itself, of the following
type: T=I+u where u takes its values in the Cameron-Martin space H. Assume also
that u is a finite sum of H-valued multiple Ito-Wiener integrals. In this work
we prove that if T preserves the Wiener measure, then necessarily u is in the
first Wiener chaos and the transformation corresponding to it is a rotation in
the sense of [9]. Afterwards the ergodicity and mixing of such transformations,
which are second quantizations of the unitary operators on the Cameron-Martin
space, are characterized. Finally, the ergocity of the transformation
dY_t=gamma(t)dW_t, 0 \le t \le 1 where W is n-dimensional Wiener and gamma is
non random is characterized

</DOC>
<DOC>
<DOCNO> 102343 </DOCNO>
Notes on the quantum tetrahedron


  This is a set of notes describing several aspects of the space of paths on
ADE Dynkin diagrams, with a particular attention paid to the graph E6. Many
results originally due to A. Ocneanu are here described in a very elementary
way (manipulation of square or rectangular matrices). We recall the concept of
essential matrices (intertwiners) for a graph and describe their module
properties with respect to right and left actions of fusion algebras. In the
case of the graph E6, essential matrices build up a right module with respect
to its own fusion algebra but a left module with respect to the fusion algebra
of A11. We present two original results: 1) Our first contribution is to show
how to recover the Ocneanu graph of quantum symmetries of the Dynkin diagram E6
from the natural multiplication defined in the tensor square of its fusion
algebra (the tensor product should be taken over a particular subalgebra); this
is the Cayley graph for the two generators of the twelve dimensional algebra E6
\otimes_A3 E6 and E6 refer to the commutative fusion algebras of the
corresponding graphs). 2) To every point of the graph of quantum symmetries one
can associate a particular matrix describing the `` torus structure'' of the
chosen Dynkin diagram; following Ocneanu, one obtains in this way, in the case
of E6, twelve such matrices of dimension 11x11, one of them is a modular
invariant and encodes the partition function of the corresponding conformal
field theory. Our own next contribution is to provide a simple algorithm for
the determination of these matrices.

</DOC>
<DOC>
<DOCNO> 40585 </DOCNO>
(3+1)-spectrum of neutrino masses: A chance for LSND?


  If active to active neutrino transitions are dominant modes of the
atmospheric ($\nu_{\mu} \to \nu_{\tau}$) and the solar neutrino oscillations
($\nu_{e}\to \nu_{\mu}/\nu_{\tau}$), as is indicated by recent data, the
favoured scheme which accommodates the LSND result - the so called (2+2)-scheme
- should be discarded. We introduce the parameters $\eta_s^{atm}$ and
$\eta_s^{sun}$ which quantify an involvement of the sterile component in the
solar and atmospheric neutrino oscillations. The (2+2)-scheme predicts
$\eta_s^{atm} + \eta_s^{sun} = 1$ and the experimental proof of deviation from
this equality will discriminate the scheme. In this connection the (3+1)-scheme
is revisited in which the fourth (predominantly sterile) neutrino is isolated
from a block of three flavour neutrinos by the mass gap $\Delta m^2_{LSND} \sim
(0.4-10)$ eV$^2$. We find that in the (3+1)-scheme the LSND result can be
reconciled with existing bounds on $\nu_e$- and $\nu_{\mu}$ - disappearance at
95-99 % C.L.. The generic prediction of the scheme is the $\nu_e$- and
$\nu_{\mu}$ - disappearance probabilities at the level of present experimental
bounds. The possibility to strengthen the bound on $\nu_{\mu}$- disappearance
in the KEK - front detector experiment is studied. We consider phenomenology of
the (3 + 1)-scheme, in particular, its implications for the atmospheric
neutrinos, neutrinoless double beta decay searches, supernova neutrinos and
primordial nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 11263 </DOCNO>
Dzyaloshinskii-Moriya interaction in the paramagnetic state and the


  Dzyaloshinskii-Moriya (DM) interaction in the paramagnetic state leads to the
incommensurate spin fluctuations with incommensurate vector proportional to the
relative strength of the DM interaction. We show that the DM interaction leads
to helical spin fluctuations which may be observed by the polarized neutron
scattering.

</DOC>
<DOC>
<DOCNO> 80806 </DOCNO>
The dual of pure non-Abelian lattice gauge theory as a spin foam model


  We derive an exact duality transformation for pure non-Abelian gauge theory
regularized on a lattice. The duality transformation can be applied to gauge
theory with an arbitrary compact Lie group G as the gauge group and on
Euclidean space-time lattices of dimension d >= 2. It maps the partition
function as well as the expectation values of generalized non-Abelian Wilson
loops (spin networks) to expressions involving only finite-dimensional unitary
representations, intertwiners and characters of G. In particular, all group
integrations are explicitly performed. The transformation maps the strong
coupling regime of non-Abelian gauge theory to the weak coupling regime of the
dual model. This dual model is a system in statistical mechanics whose
configurations are spin foams on the lattice.

</DOC>
<DOC>
<DOCNO> 170182 </DOCNO>
Mermin's n-particle Bell inequality and operators' noncommutativity


  The relationship between the noncommutativity of operators and the violation
of the Bell inequality is exhibited in the light of the n-particle Bell-type
inequality discovered by Mermin [PRL 65, 1838 (1990)]. It is shown, in
particular, that the maximal amount of violation of Mermin's inequality
predicted by quantum mechanics decreases exponentially by a factor of 2^{-m/2}
whenever any m among the n single-particle commutators happen to vanish.

</DOC>
<DOC>
<DOCNO> 117917 </DOCNO>
The Black Hole Mass - Galaxy Age Relation


  We present evidence that there is a significant correlation between the
fraction of a galaxy's mass that lies in its central black hole and the age of
the galaxy's stellar population. Since the absorption line indices that are
used to estimate the age are luminosity weighted, they essentially measure the
time since the last significant episode of star formation in the galaxy. The
existence of this correlation is consistent with several theories of galaxy
formation, including the currently-favoured hierarchical picture of galaxy
evolution, which predicts just such a relation between black hole mass and the
time since the last burst of merger-induced star formation. It is not
consistent with models in which the massive black hole is primordial, and hence
uncoupled from the stellar properties of the galaxy.

</DOC>
<DOC>
<DOCNO> 8240 </DOCNO>
Argon annealing of the oxygen-isotope exchanged manganite


  We have resolved a controversial issue concerning the oxygen-isotope shift of
the ferromagnetic transition temperature T_{C} in the manganite
La_{0.8}Ca_{0.2}MnO_{3+y}. We show that the giant oxygen-isotope shift of T_C
observed in the normal oxygen-isotope exchanged samples is indeed intrinsic,
while a much smaller shift observed in the argon annealed samples is an
artifact. The argon annealing causes the 18O sample to partially exchange back
to the 16O isotope due to a small 16O contamination in the Ar gas. Such a
contamination is commonly caused by the oxygen outgas that is trapped in the
tubes, connectors and valves. The present results thus umambiguously
demonstrate that the observed large oxygen isotope effect is an intrinsic
property of manganites, and places an important constraint on the basic physics
of these materials.

</DOC>
<DOC>
<DOCNO> 170474 </DOCNO>
Quantum Erasure by Transverse Indistinguishability


  We show that the first experiment with double-slits and twin photons detected
in coincidence can be understood as a quantum eraser. The ``which path''
information is erased by transverse indistinguishability obtained by means of
mode filtering in the twin conjugated beam. A delayed choice quantum eraser
based on the same scheme is proposed.

</DOC>
<DOC>
<DOCNO> 174473 </DOCNO>
Signals for a Transition from Surface to Bulk Emission in Thermal


  Excitation-energy-gated two-fragment correlation functions have been studied
between 2 to 9A MeV of excitation energy for equilibrium-like sources formed in
$\pi^-$ and p + $^{197}$Au reactions at beam momenta of 8,9.2 and 10.2 GeV/c.
Comparison of the data to an N-body Coulomb-trajectory code shows a decrease of
one order of magnitude in the fragment emission time in the excitation energy
interval 2-5A MeV, followed by a nearly constant breakup time at higher
excitation energy. The observed decrease in emission time is shown to be
strongly correlated with the increase of the fragment emission probability, and
the onset of thermally-induced radial expansion. This result is interpreted as
evidence consistent with a transition from surface-dominated to bulk emission
expected for spinodal decomposition.

</DOC>
<DOC>
<DOCNO> 81022 </DOCNO>
Noncommutative String Worldsheets from Matrix Models


  We study dynamical effects of introducing noncommutativity on string
worldsheets by using a matrix model obtained from the zero-volume limit of
four-dimensional SU($N$) Yang-Mills theory. Although the dimensionless
noncommutativity parameter is of order 1/N, its effect is found to be
non-negligible even in the large $N$ limit due to the existence of higher
Fourier modes. We find that the Poisson bracket grows much faster than the
Moyal bracket as we increase $N$, which means in particular that the two
quantities do not coincide in the large $N$ limit. The well-known instability
of bosonic worldsheets due to long spikes is shown to be cured by the
noncommutativity. The extrinsic geometry of the worldsheet is described by a
crumpled surface with a large Hausdorff dimension.

</DOC>
<DOC>
<DOCNO> 99629 </DOCNO>
Partitions with parts in a finite set


  Let A be a nonempty finite set of relatively prime positive integers, and let
p_A(n) denote the number of partitions of n with parts in A. An elementary
arithmetic argument is used to obtain an asymptotic formula for p_A(n).

</DOC>
<DOC>
<DOCNO> 40520 </DOCNO>
Recent Results from the K2K (KEK-to-Kamioka) Neutrino Oscillation


  The latest results of the K2K experiment are reported. The results are based
on data taken from June, 1999, to June, 2000, corresponding to a total $2.6
\cdot 10^{19}$ protons on target. Twenty seven fully-contained events in the
22.5 kton fiducial volume of Super-Kamiokande (SK) are observed. The expected
number of events is estimated to be 40.3^{+4.7}_{-4.6} assuming the null
oscillations hypothesis.

</DOC>
<DOC>
<DOCNO> 11798 </DOCNO>
Field-Induced Gaps in the Frustrated Spin Ladder


  We study the magnetization process of the $S=1/2$ antiferromagnetic spin
ladder in the presence of the second and the third-neighbor couplings which
lead to frustration with the typical nearest-neighbor coupling. We use
degenerate perturbation theory and level spectroscopy analysis of the numerical
diagonalization data of the Hamiltonian for finite systems. We find two kinds
of plateaux at half the saturation moment in the magnetization curve. One is
mainly due to the second-neighbor couplings and the other to the third-neighbor
couplings. The mechanisms of these two plateaux are quite different with each
other.

</DOC>
<DOC>
<DOCNO> 150550 </DOCNO>
Renormalizations in softly broken N=1 theories: Slavnov-Taylor


  Slavnov-Taylor identities have been applied to perform explicitly the
renormalization procedure for the softly broken N=1 SYM. The result is in
accordance with the previous results obtained at the level of supergraph
technique.

</DOC>
<DOC>
<DOCNO> 101420 </DOCNO>
Distribution of the partition function modulo m


  Ramanujan (and others) proved that the partition function satisfies a number
of striking congruences modulo powers of 5, 7 and 11. A number of further
congruences were shown by the works of Atkin, O'Brien, and Newman. In this
paper we prove that there are infinitely many such congruences for every prime
modulus exceeding 3. In addition, we provide a simple criterion guaranteeing
the truth of Newman's conjecture for any prime modulus exceeding 3 (recall that
Newman's conjecture asserts that the partition function hits every residue
class modulo a given integer M infinitely often).

</DOC>
<DOC>
<DOCNO> 178511 </DOCNO>
Invariant Manifolds and Collective Coordinates


  We introduce suitable coordinate systems for interacting many-body systems
with invariant manifolds. These are Cartesian in coordinate and momentum space
and chosen such that several components are identically zero for motion on the
invariant manifold. In this sense these coordinates are collective. We make a
connection to Zickendraht's collective coordinates and present certain
configurations of few-body systems where rotations and vibrations decouple from
single-particle motion. These configurations do not depend on details of the
interaction.

</DOC>
<DOC>
<DOCNO> 40656 </DOCNO>
Jet Production in DIS at HERA


  Data on jet production in deep inelastic e^+ p scattering are presented.
 The results are compared with pQCD calculations. At low Q^2 no consistent
description of the data over all the phase space is available yet. At high Q^2
(>150 GeV^2) the data are well described by pQCD in NLO.

</DOC>
<DOC>
<DOCNO> 83389 </DOCNO>
Nimrod/G: An Architecture of a Resource Management and Scheduling System


  The availability of powerful microprocessors and high-speed networks as
commodity components has enabled high performance computing on distributed
systems (wide-area cluster computing). In this environment, as the resources
are usually distributed geographically at various levels (department,
enterprise, or worldwide) there is a great challenge in integrating,
coordinating and presenting them as a single resource to the user; thus forming
a computational grid. Another challenge comes from the distributed ownership of
resources with each resource having its own access policy, cost, and mechanism.
  The proposed Nimrod/G grid-enabled resource management and scheduling system
builds on our earlier work on Nimrod and follows a modular and component-based
architecture enabling extensibility, portability, ease of development, and
interoperability of independently developed components. It uses the Globus
toolkit services and can be easily extended to operate with any other emerging
grid middleware services. It focuses on the management and scheduling of
computations over dynamic resources scattered geographically across the
Internet at department, enterprise, or global level with particular emphasis on
developing scheduling schemes based on the concept of computational economy for
a real test bed, namely, the Globus testbed (GUSTO).

</DOC>
<DOC>
<DOCNO> 121848 </DOCNO>
Fast CMB Analyses via Correlation Functions


  We propose and implement a fast, universally applicable method for extracting
the angular power spectrum C_l from CMB temperature maps by first estimating
the correlation function \xi(\theta). Our procedure recovers the C_l's using
N^2 (but potentially N logN), operations, where N is the number of pixels. This
is in contrast with standard maximum likelihood techniques which require N^3
operations. Our method makes no special assumptions about the map, unlike
present fast techniques which rely on symmetries of the underlying noise
matrix, sky coverage, scanning strategy, and geometry. This enables for the
first time the analysis of megapixel maps without symmetries. The key element
of our technique is the accurate multipole decomposition of \xi(\theta). The
C_l error bars and cross-correlations are found by a Monte-Carlo approach. We
applied our technique to a large number of simulated maps with Boomerang sky
coverage in 81000 pixels. We used a diagonal noise matrix, with approximately
the same amplitude as Boomerang. These studies demonstrate that our technique
provides an unbiased estimator of the C_l's. Even though our method is
approximate, the error bars obtained are nearly optimal, and converged only
after few tens of Monte-Carlo realizations. Our method is directly applicable
for the non-diagonal noise matrix. This, and other generalizations, such as
minimum variance weighting schemes, polarization, and higher order statistics
are also discussed.

</DOC>
<DOC>
<DOCNO> 99801 </DOCNO>
Seiberg-Witten invariants of non-simple type and Einstein metrics


  We construct examples of four dimensional manifolds with Spin$^c$-structures,
whose moduli spaces of solutions to the Seiberg-Witten equations, represent a
non-trivial bordism class of positive dimension, i.e. the Spin$^c$-structures
are not induced by almost complex structures. As an application, we show the
existence of infinitely many non-homeomorphic compact oriented 4-manifolds with
free fundamental group and predetermined Euler characteristic and signature
that do not carry Einstein metrics.

</DOC>
<DOC>
<DOCNO> 8374 </DOCNO>
Induced instability for boson-fermion mixed condensate of Alkali atoms


  Instabilities for boson-fermion mixed condensates of trapped Alkali atoms due
to the boson-fermion attractive interaction are studied using a variational
method. Three regions are shown for their instabilities according to the
boson-fermion interaction strength: stable, meta-stable and unstable ones. The
stability condition is obtained analytically from the asymptotic expansion of
the variational total energy. The life-time of metastable states is discussed
for tunneling decay, and is estimated to be very long. It suggests that, except
near the unstable border, meta-stable mixed condensate should be almost-stable
against clusterizations. The critical border between meta-stable and unstable
phases is calculated numerically and is shown to be consistent with the
M{\o}lmer scaling condition.

</DOC>
<DOC>
<DOCNO> 100973 </DOCNO>
A note on polarizations of finitely generated fields


  In our previous paper, we established Northcott's theorem for height
functions over finitely generated fields. Unfortunately, Northcott's theorem on
finitely generated fields does not hold in general. Actually, it depends on the
choice of a polarization. In this short note, we will propose a weaker
condition of the polarization to guarantee Northcott's theorem. We will also
show the generalization of conjectures of Bogomolov and Lang in under the
weaker condition.

</DOC>
<DOC>
<DOCNO> 71569 </DOCNO>
Heavy Quark Physics on the Lattice


  I review the current status of lattice calculations of the properties of
bound states containing one or more heavy quarks. Many of my remarks focus on
the heavy-light leptonic decay constants, such as $f_B$, for which the
systematic errors have by now been quite well studied. I also discuss
$B$-parameters, semileptonic form factors, and the heavy-light and heavy-heavy
spectra. Some of my ``world averages'' are: $f_B=200(30) MeV$, $f_B\sqrt{\hat
B_{B_d}}= 230(40) MeV$, $f_{B_s}/f_B=1.16(4)$ and $f_{B_s}\sqrt{\hat
B_{B_s}}/f_B\sqrt{\hat B_{B_d}}=1.16(5)$.

</DOC>
<DOC>
<DOCNO> 178926 </DOCNO>
Finite range effects of nuclear force in intermediate energy heavy ion


  Within the framework of an isospin-dependent quantum molecular dynamics
model, the zero-range 2-body part of the Skyrme interaction is replaced by a
finite-range Gaussian 2-body interaction. From the transverse momentum analysis
in the reaction of system $^{93}$Nb + $^{93}$Nb at energy of 400 MeV/nucleon
and impact parameter $b$=3 fm, it is shown that the finite-range nuclear force
enhances the transverse momentum of the reaction system and it can partly
replace the momentum dependent part of the nucleon-nucleon interaction.

</DOC>
<DOC>
<DOCNO> 10844 </DOCNO>
The dissipative quantum model of brain: how do memory localize in


  The mechanism of memory localization in extended domains is described in the
framework of the parametric dissipative quantum model of brain. The size of the
domains and the capability in memorizing depend on the number of links the
system is able to establish with the external world.

</DOC>
<DOC>
<DOCNO> 116992 </DOCNO>
Applications of Time Domain Simulation to Coupler Design for Periodic


  We present numerical procedures for analyzing the properties of periodic
structures and associated couplers based upon time domain simulation. Simple
post processing procedures are given for determining Brillouin diagrams and
complex field distributions of the traveling wave solutions, and the reflection
coefficient of the traveling waves by the input and output. The availability of
the reflection coefficient information facilitates a systematic and efficient
procedure for matching the input and output. The method has been extensively
applied to coupler design for a wide variety of structures and to a study
directed towards elimination of the surface field enhancement commonly
experienced in coupler cells.

</DOC>
<DOC>
<DOCNO> 72162 </DOCNO>
On Higgs Production in Photon Photon Collisions


  I review recent progress on the Higgs production in gamma gamma collisions at
the photon mode of the Next Linear Collider (NLC). I mainly focus on two
particular topics. The first topic is the Higgs-two photon vertex, which is
sensitive to new physics, and can be considered a counter of the number of new
heavy particles. I recall the results on QCD and electroweak two loop radiative
corrections. The second topic is the heavy quark anti-quark pair production in
gamma gamma collisions, which is the dominant background process for the Higgs
production at m_H <150 GeV. We suggest a procedure for the resummation of
double (DL) and single (SL) logarithms in the process gamma gamma -> b anti-b.

</DOC>
<DOC>
<DOCNO> 40019 </DOCNO>
The quest for the neutrino mass spectrum


  This article provides a (semi-)popular introduction to the phenomenology of
neutrino masses.

</DOC>
<DOC>
<DOCNO> 40476 </DOCNO>
Direct Detection of Neutralino Dark Matter and the Anomalous Dipole


  We compare predictions for the spin-independent contribution to the
neutralino-proton scattering cross section $\sig$ and for the anomalous
magnetic dipole moment of the muon, $a_\mu = (g_\mu-2)/2$, in models with
gravity-mediated supersymmetry breaking. We nearly always find a positive
correlation between these two measurables, i.e. scenarios with larger $a_\mu$
also tend to have larger $\sig$, but the detailed prediction differs greatly
between models. In particular, we find that for the popular mSUGRA scenario
with universal soft breaking masses at the scale of Grand Unification,
measurements of $a_\mu$ currently seem more promising. On the other hand, if
scalar soft breaking masses at the GUT scale receive sizable contributions from
SO(10) D-terms, one often finds scenarios with large $\sig$ but $a_\mu$ below
the currently foreseen sensitivity. A string-inspired model with non-universal
scalar spectrum at the GUT scale falls between these two cases.

</DOC>
<DOC>
<DOCNO> 178510 </DOCNO>
Reduction of superfluid gap by scattering


  The effect nucleon dressing by scattering on the pairing gap in nuclear
matter is discussed. Numerical results from self-consistent T-matrix
calculations are compared to quasi-particle approximations. The dominant effect
of scattering can be accounted for by a renormalization of the quasi-particle
strength. The exponential sensitivity of the pairing gap and the critical
temperature on the pairing strength makes it strongly dependent on many-body
effects.

</DOC>
<DOC>
<DOCNO> 39633 </DOCNO>
Epsilon-prime / epsilon Results from KTeV


  The first measurement of epsilon-prime / epsilon from the KTeV experiment at
Fermilab is described.

</DOC>
<DOC>
<DOCNO> 12741 </DOCNO>
On the Causality and Stability of the Relativistic Diffusion Equation


  This paper examines the mathematical properties of the relativistic diffusion
equation. The peculiar solution which Hiscock and Lindblom identified as an
instability is shown to emerge from an ill-posed initial value problem. These
do not meet the mathematical conditions required for realistic physical
problems and can not serve as an argument against the relativistic
hydrodynamics of Landau and Lifshitz.

</DOC>
<DOC>
<DOCNO> 118166 </DOCNO>
Observational Evidence for Massive Black Holes in the Centers of Active


  Naturally occurring water vapor maser emission at 1.35 cm wavelength provides
an accurate probe for the study of accretion disks around highly compact
objects, thought to be black holes, in the centers of active galaxies. Because
of the exceptionally fine angular resolution, 200 microarcseconds, obtainable
with very long baseline interferometry, accompanied by high spectral
resolution, < 0.1 km/s, the dynamics and structures of these disks can be
probed with exceptional clarity. The data on the galaxy NGC4258 are discussed
here in detail. The mass of the black hole binding the accretion disk is 3.9
times 10^7 solar masses. Although the accretion disk has a rotational period of
about 800 years, the physical motions of the masers have been directly measured
with VLBI over a period of a few years. These measurements also allow the
distance from the earth to the black hole to be estimated to an accuracy of 4
percent. The status of the search for other maser/black hole candidates is also
discussed.

</DOC>
<DOC>
<DOCNO> 11160 </DOCNO>
A Crossed Sliding Luttinger Liquid Phase


  We study a system of crossed spin-gapped and gapless Luttinger liquids. We
establish the existence of a stable non-Fermi liquid state with a
finite-temperature,long-wavelength, isotropic electric conductivity that
diverges as a power law in temperature $T$ as $T\to 0$. This two-dimensional
system has many properties characteristic of a true isotropic Luttinger liquid,
though at zero temperature it becomes anisotropic. This model can easily be
extended to three dimensions.

</DOC>
<DOC>
<DOCNO> 40259 </DOCNO>
Phenomenology of Radion in Randall-Sundrum Scenario


  The success of the Randall-Sundrum scenario relies on stabilization of the
modulus field or the radion, which is the scalar field about the background
geometry. The stabilization mechanism proposed by Goldberger and Wise has the
consequence that this radion is lighter than the graviton Kaluza-Klein states
so that the first particle to be discovered is the radion. In this work, we
study in details the decay, production, and detection of the radion at
hadronic, $e^+ e^-$, and $\gamma\gamma$ colliders.

</DOC>
<DOC>
<DOCNO> 85655 </DOCNO>
Possible direct method to determine the radius of a star from the


  We compute the spectrum and the waveform of gravitational waves generated by
the inspiral of a disk or a spherical like dust body into a Kerr black hole. We
investigate the effect of the radius R of the body on gravitational waves and
conclude that the radius is inferred from the gravitational wave signal
irrespective of (1) the form of the body (a disk or a spherical star) (2) the
location where the shape of the body is determined, (3) the orbital angular
momentum of the body, and (4) a black hole rotation. We find that when $R$ is
much larger than the characteristic length of the quasinormal mode frequency,
the spectrum has several peaks and the separation of the troughs $\Delta\omega$
is proportional to $R^{-1}$. Thus, we may directly determine the radius of a
star in a coalescing binary black hole - star system from the observed spectrum
of gravitational waves. For example, both trough frequency of neutron stars and
white dwarfs are within the detectable frequency range of some laser
interferometers and resonant type detectors so that this effect can be observed
in the future. We therefore conclude that the spectrum of gravitational waves
may provide us important signals in gravitational wave astronomy as in optical
astronomy.

</DOC>
<DOC>
<DOCNO> 71577 </DOCNO>
Analysis of the DeltaI=1/2 Rule and e'/e with Overlap Fermions


  We study the renormalization of the DeltaS=1 effective weak Hamiltonian with
overlap fermions. The mixing coefficients among dimension-six operators are
computed at one loop in perturbation theory. As a consequence of the chiral
symmetry at finite lattice spacing and of the GIM mechanism, which turns out to
be quadratic in the masses, the K-->pi pi and K -->pi matrix elements relevant
for the Delta I =1/2 rule can be computed without any power subtractions. The
analogous amplitudes for e'/e require one divergent subtraction only, which can
be performed non-perturbatively using K-->0 matrix elements.

</DOC>
<DOC>
<DOCNO> 169591 </DOCNO>
Discussion: Byrne and Hall on Everett and Chalmers


  Byrne and Hall (1999) criticized the argument of Chalmers (1996) in favor of
the Everett-style interpretation. They claimed to show ``the deep and
underappreciated flaw in ANY Everett-style interpretation''. I will argue that
it is possible to interpret Chalmers's writing in such a way that most of the
criticism by Byrne and Hall does not apply. In any case their general criticism
of the many-worlds interpretation is unfounded. The recent recognition that the
Everett-style interpretations are good (if not the best) interpretations of
quantum mechanics has, therefore, not been negated.

</DOC>
<DOC>
<DOCNO> 101445 </DOCNO>
On Bures distance over standard form vN-algebras


  In case of a standard form vN-algebra, the Bures distance is the natural
distance between the fibres of implementing vectors at normal positive linear
forms. Thereby, it is well-known that to each two normal positive linear forms
implementing vectors exist such that the Bures distance is attained by the
metric distance of the implementing vectors in question. We discuss to which
extend this can remain true if a vector in one of the fibres is considered as
fixed. For each nonfinite algebra, classes of counterexamples are given and
situations are analyzed where the latter type of result must fail. In the
course of the paper, an account of those facts and notions is given, which can
be taken as a useful minimum of basic C^*-algebraic tools needed in order to
efficiently develop the fundamentals of Bures geometry over standard form
vN-algebras.

</DOC>
<DOC>
<DOCNO> 170460 </DOCNO>
Experiments towards quantum information with trapped Calcium ions


  Ground state cooling and coherent manipulation of ions in an rf-(Paul) trap
is the prerequisite for quantum information experiments with trapped ions. With
resolved sideband cooling on the optical S1/2 - D5/2 quadrupole transition we
have cooled one and two 40Ca+ ions to the ground state of vibration with up to
99.9% probability. With a novel cooling scheme utilizing electromagnetically
induced transparency on the S1/2 - P1/2 manifold we have achieved simultaneous
ground state cooling of two motional sidebands 1.7 MHz apart. Starting from the
motional ground state we have demonstrated coherent quantum state manipulation
on the S1/2 - D5/2 quadrupole transition at 729 nm. Up to 30 Rabi oscillations
within 1.4 ms have been observed in the motional ground state and in the n=1
Fock state. In the linear quadrupole rf-trap with 700 kHz trap frequency along
the symmetry axis (2 MHz in radial direction) the minimum ion spacing is more
than 5 micron for up to 4 ions. We are able to cool two ions to the ground
state in the trap and individually address the ions with laser pulses through a
special optical addressing channel.

</DOC>
<DOC>
<DOCNO> 99705 </DOCNO>
A combinatorial approach to quantification of Lie algebras


  We propose a notion of a quantum universal enveloping algebra for an
arbitrary Lie algebra defined by generators and relations which is based on the
quantum Lie operation concept. This enveloping algebra has a PBW basis that
admits the Kashiwara crystalization. We describe all skew primitive elements of
the quantum universal enveloping algebra for the classical nilpotent algebras
of the infinite series defined by the Serre relations and prove that the set of
PBW-generators for each of these enveloping algebras coincides with the
Lalonde-Ram basis of the ground Lie algebra with a skew commutator in place of
the Lie operation. The similar statement is valid for Hall-Shirshov basis of
any Lie algebra defined by one relation, but it is not so in general case.

</DOC>
<DOC>
<DOCNO> 69761 </DOCNO>
Resolution of the strong CP problem


  It is shown that the quark mass aligns QCD $\theta$ vacuum in such a way that
the strong CP is conserved, resolving the strong CP problem.

</DOC>
<DOC>
<DOCNO> 121480 </DOCNO>
A study of the core of the Shapley Concentration: V. The A3528 complex:


  We present the results of a redshift survey of galaxies in the A3528 complex,
a chain of interacting clusters in the core of the Shapley Concentration. This
complex is characterized in the X-ray band by two pairs of roughly similar
interacting clumps: one pair has been resolved as two optical Abell clusters
(A3530 and A3532), while the two components of the other pair are both
associated to A3528. The optical data show that the distance between the
centers of A3530 and A3532 is smaller than their Abell radii, an indication of
the existence at least of tidal interactions, and that the contours of galaxies
in A3528 appear to be elongated in the North-South direction, pointing towards
the A3530-A3532 pair.
 From our survey we obtained ~600 new radial velocity determinations: using
this sample, we studied the dynamics of the four Abell clusters in this region
(A3528, A3530, A3532 and A3535) and derived their mean velocities and velocity
dispersions. Moreover we performed a substructure analysis, both bi-dimensional
and three-dimensional, of the whole complex.
 All the characteristics of this structure seem to point toward a merging
scenario in an early stage, whose effects on the galaxy population and on the
cluster dynamics are not yet evident, contrary to what happens in the nearby
A3558 complex, where the merging events are in a rather advanced stage and were
already able to induce modifications in the galaxy population.

</DOC>
<DOC>
<DOCNO> 67709 </DOCNO>
Conversion of neutron stars to strange stars as the central engine of


  We study the conversion of a neutron star to a strange star as a possible
energy source for gamma-ray bursts. We use different recent models for the
equation of state of neutron star matter and strange quark matter. We show that
the total amount of energy liberated in the conversion is in the range of (1-4)
10^{53} ergs (one order of magnitude larger than previous estimates) and is in
agreement with the energy required to power gamma-ray burst sources at
cosmological distances.

</DOC>
<DOC>
<DOCNO> 117527 </DOCNO>
Structure of the solar core: Effect of asymmetry of peak profiles


  Recent studies have established that peaks in solar oscillation power spectra
are not Lorentzian in shape, but have a distinct asymmetry. Fitting a symmetric
Lorentzian profile to the peaks therefore produces a shift in frequency of the
modes. Accurate determination of low-frequency modes is essential to infer the
structure of the solar core by inversion of the mode frequencies. In this paper
we investigate how the changes in frequencies of low-degree modes obtained by
fitting symmetric and asymmetric peak profiles change the inferred properties
of the solar core. We use data obtained by the Global Oscillations at Low
Frequencies (GOLF) project on board the SoHO spacecraft. Two different solar
models and inversion procedures are used to invert the data to determine the
sound speed in the solar core. We find that for a given set of modes no
significant difference in the inferred sound-speed results from taking
asymmetry into account when fitting the low-degree modes.

</DOC>
<DOC>
<DOCNO> 151549 </DOCNO>
Knot Invariants and Chern-Simons Theory


  A brief review of the development of Chern-Simons gauge theory since its
relation to knot theory was discovered in 1988 is presented. The presentation
is done guided by a dictionary which relates knot theory concepts to quantum
field theory ones. From the basic objects in both contexts the quantities
leading to knot and link invariants are introduced and analyzed. The quantum
field theory approaches that have been developed to compute these quantities
are reviewed. Perturbative approaches lead to Vassiliev or finite type
invariants. Non-perturbative ones lead to polynomial or quantum group
invariants. In addition, a brief discussion on open problems and future
developments is included.

</DOC>
<DOC>
<DOCNO> 117594 </DOCNO>
Solar-Like Cycle in Asymptotic Giant Branch Stars


  I propose that the mechanism behind the formation of concentric semi-periodic
shells found in several planetary nebulae (PNs) and proto-PNs, and around one
asymptotic giant branch (AGB) star, is a solar-like magnetic activity cycle in
the progenitor AGB stars. The time intervals between consecutive ejection
events is about 200-1,000 years, which is assumed to be the cycle period (the
full magnetic cycle can be twice as long, as is the 22-year period in the sun).
The magnetic field has no dynamical effects; it regulates the mass loss rate by
the formation of magnetic cool spots. The enhanced magnetic activity at the
cycle maximum results in more magnetic cool spots, which facilitate the
formation of dust, hence increasing the mass loss rate. The strong magnetic
activity implies that the AGB star is spun up by a companion, via a tidal or
common envelope interaction. The strong interaction with a stellar companion
explains the observations that the concentric semi-periodic shells are found
mainly in bipolar PNs.

</DOC>
<DOC>
<DOCNO> 122320 </DOCNO>
Evolution of the Cluster Mass Function: Gpc^3 Dark Matter Simulations


  High-resolution N-body simulations of four popular Cold Dark Matter
cosmologies (LCDM, OCDM, QCDM, and tilted SCDM), each containing 10^5 clusters
of galaxies in a cubic gigaparsec volume, are used to determine the evolution
of the cluster mass function from z=3 to z=0. The large volume and high
resolution of these simulations allow an accurate measure of the evolution of
cosmologically important (but rare) massive clusters at high redshift. The
simulated mass function is presented for cluster masses within several radii
typically used observationally (R=0.5, 1.0, and 1.5 Mpc/h, both comoving and
physical) in order to enable direct comparison with current and future
observations. The simulated evolution is compared with current observations of
massive clusters at redshifts 0.3<z<0.8. The Omega_m=1 tilted SCDM model, which
exhibits very rapid evolution of the cluster abundance, produces too few
clusters at z>0.3 and no massive clusters at z>0.5, in stark contradiction with
observations. The Omega_m=0.3 models- LCDM, OCDM, and QCDM- all exhibit
considerably weaker evolution and are consistent with current data. Among these
low density models, OCDM evolves the least. These trends are enhanced at high
redshift and can be used to discriminate between flat and open low density
models. The simulated mass functions are compared with the Press-Schechter
approximation. Standard Press-Schechter predicts too many low mass clusters at
z=0, and too few clusters at higher redshift. We modify the approximation by a
simple parameterization of the density contrast threshold for collapse, which
has a redshift dependence. This modified Press-Schechter approximation provides
a good fit to the simulated mass functions.

</DOC>
<DOC>
<DOCNO> 8153 </DOCNO>
A New Two-Pole Approximation in the Hubbard Model. Metal-Insulator


  A new two-pole approximation, which allows to describe the transition from an
insulating state to a metallic one at increase of bandwidth, and also the
observable in some compounds transition from a metalic state to an insulating
one with increasing temperature, is presented. The case of a paramagnetic
narrow-band material at half-filling is considered. Single-particle Green
function and energy spectrum of electron system are calculated. The expressions
for energy gap width and the concentration of polar states (holes or doublons)
are obtained. The conditions for metallic and insulating states are found.

</DOC>
<DOC>
<DOCNO> 13946 </DOCNO>
History Dependent Phenomena in the Transverse Ising Ferroglass: the Free


  In this paper we investigate the relationship between glassy and
ferromagnetic phases in disordered Ising ferromagnets in the presence of
transverse magnetic fields, $\Gamma$. Iterative mean field simulations probe
the free energy landscape and suggest the existence of a glass transition as a
function of $\Gamma$ which is distinct from the Curie temperature. New
experimental field-cooled and zero-field-cooled data on LiHo$_x$Y$_{1-x}$F$_4$
provide support for our theoretical picture.

</DOC>
<DOC>
<DOCNO> 152241 </DOCNO>
String field theory at large B-field and noncommutative geometry


  In the search for the exact minimum of the tachyon potential in the Witten's
cubic string field theory we try to learn as much as possible from the string
field theory in the large B-field background. We offer a simple alternative
proof of the Witten's factorization, carry out the analysis of string field
equations also for the noncommutative torus and find some novel relations to
the algebraic K-theory. We note an intriguing relation between Chern-Simons and
Chern classes of two noncommutative bundles. Finally we observe a certain
pattern which enables us to make a plausible conjecture about the exact form of
the minimum.

</DOC>
<DOC>
<DOCNO> 116262 </DOCNO>
On variational solution of the four-body Santilli-Shillady model of


  In this paper, we apply Ritz variational approach to a new isochemical model
of $H_2$ molecule suggested by Santilli and Shillady. We studied Gaussian,
$V_g$, and exponential, $V_e$, screened Coloumb potential {\it approximations},
as well as the original Hulten potential, $V_h$, case. Both the Coloumb and
exchange integrals have been calculated only for $V_e$ owing to Gegenbauer
expansion while for $V_g$ and $V_h$ cases we achieved analytical results only
for the Coloumb integrals. We conclude that the $V_e$-based model is capable to
fit experimental data on $H_2$ molecule in confirmation of the results of
numerical HFR approach by Santilli and Shillady. Also, we achieved the
energy-based estimation of the weight of the isoelectronium phase which is
appeared to be of the order of 1%...6%, for the case of $V_e$. However, we note
that this is {\it not} the result corresponding to the original
Santilli-Shillady model, which is based on the Hulten potential $V_h$. An
interesting result is that in order to prevent divergency of the Coloumb
integral for $V_h$ the correlation length parameter $r_c$ should run discrete
set of values. We used this condition in our $V_e$-based model.

</DOC>
<DOC>
<DOCNO> 67785 </DOCNO>
Chargino Pair Production at $e^+e^-$ Colliders with Polarized Beams


  The chargino $\tilde{\chi}^\pm_{1,2}$ system can be reconstructed completely
in $e^+e^-$ collisions. By measuring the total cross sections and the
asymmetries with polarized beams in $e^+e^-\to\tilde{\chi}_i^+ \tilde{\chi}_j^-
[i,j=1,2]$, the chargino masses and the gaugino-higgsino mixing angles of these
states can be determined very accurately. If only the lightest charginos
$\tilde{\chi}_1^\pm$ are kinematically accessible, transverse beam polarization
is needed to determine the mixing angles unambiguously. From these observables
the fundamental SUSY parameters can be derived: the SU(2) gaugino mass $M_2$,
the modulus and the cosine of the CP-violating phase of the higgsino mass
parameter $\mu$, and $\tan\beta = v_2/v_1$, the ratio of the vacuum expectation
values of the two neutral Higgs doublet fields. [The remaining two-fold
ambiguity of the phase can be resolved by measuring the normal polarization of
the charginos.]

</DOC>
<DOC>
<DOCNO> 101664 </DOCNO>
A note on holomorphic extensions


  We give a criterium of holomorphy for some type formal power series. This
gives a stronger form of a Rothstein's type extension theorem for a particular
ring of holomorphic functions.

</DOC>
<DOC>
<DOCNO> 12585 </DOCNO>
Zipf's Law in the Liquid Gas Phase Transition of Nuclei


  Zipf's law in the field of linguistics is tested in the nuclear disassembly
within the framework of isospin dependent lattice gas model. It is found that
the average cluster charge (or mass) of rank $n$ in the charge (or mass) list
shows exactly inversely to its rank, i.e., there exists Zipf's law, at the
phase transition temperature. This novel criterion shall be helpful to search
the nuclear liquid gas phase transition experimentally and theoretically. In
addition, the finite size scaling of the effective phase transition temperature
at which the Zipf's law appears is studied for several systems with different
mass and the critical exponents of $\nu$ and $\beta$ are tentatively extracted.

</DOC>
<DOC>
<DOCNO> 150890 </DOCNO>
Turbulence as a constrained system


  Hydrodynamic turbulence is studied as a constrained system from the point of
view of metafluid dynamics. We present a Lagrangian description for this new
theory of turbulence inspired from the analogy with electromagnetism.
Consequently it is a gauge theory. This new approach to the study of turbulence
tends to renew the optimism to solve the difficult problem of turbulence. As a
constrained system, turbulence is studied in the Dirac and Faddeev-Jackiw
formalisms giving the Dirac brackets. An important result is that we show these
brackets are the same in and out of the inertial range, giving the way to
quantize turbulence.

</DOC>
<DOC>
<DOCNO> 122007 </DOCNO>
Super Eddington Atmospheres and their Winds


  We present a model for the steady state winds of super-Eddington systems.
These radiatively driven winds are expected to be optically thick and clumpy as
they arise from a porous atmosphere. The model is then used to derive the mass
loss of bright classical novae. The long duration super-Eddington outflows that
are clearly observed in at least two cases (Nova LMC 1988 #1 & Nova FH Ser) are
naturally explained. Moreover, the predicted mass loss and temperature
evolution agree nicely with the observations, as do additional features.
eta-Car is then used to double check the theory which predicts the observed
mass shed in the great eruption.

</DOC>
<DOC>
<DOCNO> 83405 </DOCNO>
Low Ambiguity in Strong, Total, Associative, One-Way Functions


  Rabi and Sherman present a cryptographic paradigm based on associative,
one-way functions that are strong (i.e., hard to invert even if one of their
arguments is given) and total. Hemaspaandra and Rothe proved that such powerful
one-way functions exist exactly if (standard) one-way functions exist, thus
showing that the associative one-way function approach is as plausible as
previous approaches. In the present paper, we study the degree of ambiguity of
one-way functions. Rabiand Sherman showed that no associative one-way function
(over a universe having at least two elements) can be unambiguous (i.e.,
one-to-one). Nonetheless, we prove that if standard, unambiguous, one-way
functions exist, then there exist strong, total, associative, one-way functions
that are $\mathcal{O}(n)$-to-one. This puts a reasonable upper bound on the
ambiguity.

</DOC>
<DOC>
<DOCNO> 122181 </DOCNO>
Energetics of jets from X-ray binaries


  I discuss the energetics of synchrotron-emitting outflows, increasingly found
to be present in many different classes of X-ray binary systems. It is shown
that the outflow is likely to be comparable in power to the integrated X-ray
luminosity, traditionally taken to be an indicator of the global mass-transfer
rate. This is especially found to be the case in the (low/)hard states of black
hole candidate systems. I conclude that jets are extremely important,
energetically and dynamically, for the accretion process in the majority of
known X-ray binary systems.

</DOC>
<DOC>
<DOCNO> 100080 </DOCNO>
On an asymptotic behavior of elements of order p in irreducible


  The behavior of the images of a fixed element of order p in irreducible
representations of a classical algebraic group in characteristic p with highest
weights large enough with respect to p and this element is investigated. More
precisely, let G be a classical algebraic group of rank r over an algebraically
closed field K of characteristic p>2. Assume that an element $x\in G$ of order
p is conjugate to that of an algebraic group of the same type and rank m<r
naturally embedded into G. Next, an integer function $\sigma_x$ on the set of
dominant weights of G and a constant $c_x$ that depend only upon x, and a
polynomial d of degree one are defined. It is proved that the image of x in the
irreducible representation of G with highest weight $\om$ contains more than
d(r-m) Jordan blocks of size p if m and r-m are not too small and
$\sigma_x(\om)\geq p-1+c_x$.

</DOC>
<DOC>
<DOCNO> 99696 </DOCNO>
Ergodicity of the action of the positive rationals on the group of


  For each \beta\in(0,+\infty) there exists a canonical measure \mu_\beta on
the ring A_f of finite adeles. We show that the positive rationals act
ergodically on (A_f,\mu_\beta) for \beta\in(0,1], and then deduce from this the
uniqueness of KMS_\beta-states for the Bost-Connes system.

</DOC>
<DOC>
<DOCNO> 67884 </DOCNO>
Quark distribution functions in the chiral quark-soliton model:


  In the framework of the chiral quark-soliton model of the nucleon we
investigate the properties of the polarized quark distribution. In particular
we analyse the so called anomalous difference between the representations of
the quark distribution functions in terms of occupied and non-occupied quark
states. By an explicit analytical calculation it is shown that this anomaly is
absent in the polarized isoscalar distribution \Delta u + \Delta d, which is
ultaviolet finite. In the case of the polarized isovector quark distribution
\Delta u - \Delta d the anomaly can be cancelled by a Pauli-Villars subtraction
which is also needed for the regularization of the ultraviolet divergence.

</DOC>
<DOC>
<DOCNO> 99770 </DOCNO>
Seshadri constant for a family of surfaces


  The aim of this note is to study local and global Seshadri constants for a
family of smooth surfaces with prescribed polarization. We shall first observe
that given $\alpha$ being smaller than the square root of the degree of
polarization, the set of local Seshadri constants in the range $(0, \alpha]$ is
finite. This in particular implies that the square root of the degree of
polarization is the only possible accumulation point of the set of local
Seshadri constants. Next we shall remark the Zariski closedness of the set of
points whose local Seshadri constants are in any given interval $(0, a]$. As
applications, we shall also add a few remarks on the lower semi-continuity of
both local and global Seshadri constants with respect to parameters involved,
and on the minimality and the maximality of their infimum and supremum.

</DOC>
<DOC>
<DOCNO> 118777 </DOCNO>
Superhumps in V348 Pup


  The eclipsing novalike cataclysmic variable star V348 Pup exhibits a
persistent luminosity modulation with a period 6 per cent longer than its 2.44
hour orbital-period (Porb). This has been interpreted as a `positive superhump'
resulting from a slowly precessing non-axisymmetric accretion disc
gravitationally interacting with the secondary. We find a clear modulation of
mid-eclipse times on the superhump period, which agrees well with the
predictions of a simple precessing eccentric disc model. Our modelling shows
that the disc light centre is on the far side of the disc from the donor star
when the superhump reaches maximum light. This phasing suggests a link between
superhumps in V348 Pup and late superhumps in SU UMa systems. Modelling of the
full lightcurve and maximum entropy eclipse mapping both show that the disc
emission is concentrated closer to the white dwarf at superhump maximum than at
superhump minimum. We detect additional signals consistent with the beat
periods between the implied disc precession period and both (1/2)Porb and
(1/3)Porb.

</DOC>
<DOC>
<DOCNO> 117167 </DOCNO>
Thomas precession angle and spinor algebra


  We present an alternative derivation of the Thomas precession angle. Using
Pauli matrices, the finite precession angle can be computed exactly. We also
discuss a new physical interpretation of the precession angle.

</DOC>
<DOC>
<DOCNO> 83203 </DOCNO>
A response to the commentaries on CoRR


  This is a response to the commentaries on "CoRR: A Computing Research
Repository".

</DOC>
<DOC>
<DOCNO> 122408 </DOCNO>
On the Hidden Nuclear Starburst in Arp 220


  We construct a starburst model for the hidden starbursts in Arp 220 based on
the new Starburst99 models of Leitherer et al. Comparing these stellar
population synthesis models with observations, we show that the hidden power
source must be due to star formation (as opposed to an AGN) at the 50% level or
more in order to avoid an ionizing photon excess problem, and this starburst
must be young ($< 7 \times 10^7$ yr). We derive a current star formation rate
of $270 M_{\odot}$ yr$^{-1}$, and an extinction $A_V > 30$ mag for our line of
sight to this hidden starburst.

</DOC>
<DOC>
<DOCNO> 123158 </DOCNO>
Ultraviolet Line Spectra of Metal-Poor Star-Forming Galaxies


  We present synthetic ultraviolet spectra of metal-poor star-forming galaxies
which were calculated with the Starburst99 package. A new spectral library was
generated from HST observations of O stars in the Large and Small Magellanic
Clouds. The corresponding mean metallicity of the synthetic spectra is
approximately 1/4\Zs. The spectra have a resolution of 1\AA and cover the
spectral range 1200-1600\AA. A set of model spectra was calculated for a
standard initial mass function and star-formation history and is compared to
synthetic spectra at solar metallicity. We find that the spectral lines are
generally weaker at lower metallicity, as expected from the lower elemental
abundances. Stellar-wind lines, however, show a more complex behavior: the
metallicity dependence of the ionization balance can be important in trace
ions, like N$^{4+}$ and Si$^{3+}$. Therefore the strength of \nv and \siiv does
not scale monotonically with metallicity. We compare our new models to
ultraviolet spectra of NGC 5253 and \cB, two star-forming galaxies with 1/4
solar metallicity at low and high redshift, respectively. The new library
provides significantly better fits to the observations than earlier models
using the \Zs library. We discuss the potential of utilizing stellar
photospheric and wind lines to estimate the chemical composition of
star-forming galaxies. The new metal-poor synthetic spectra are available via
the Starburst99 website.

</DOC>
<DOC>
<DOCNO> 10785 </DOCNO>
Pipe network model for scaling of dynamic interfaces in porous media


  We present a numerical study on the dynamics of imbibition fronts in porous
media using a pipe network model. This model quantitatively reproduces the
anomalous scaling behavior found in imbibition experiments [Phys. Rev. E {\bf
52}, 5166 (1995)]. Using simple scaling arguments, we derive a new identity
among the scaling exponents in agreement with the experimental results.

</DOC>
<DOC>
<DOCNO> 9901 </DOCNO>
Pseudogap in the Optical Spectra of UPd_2Al_3


  The in-plane optical conductivity of UPd_2Al_3 was measured at temperatures
$2 {\rm K}<T<300$ K in the spectral range from 1 cm^{-1} to 40 cm^{-1} (0.14
meV to 5 meV). As the temperature decreases below 25 K a well pronounced
pseudogap of 0.2 meV develops in the optical response. In addition we observe a
narrow conductivity peak at zero frequency which at 2 K is less than 1 cm^{-1}
wide but which contains only a fraction of the delocalized carriers. The gap in
the electronic excitations might be an inherent feature of the heavy fermioin
ground state.

</DOC>
<DOC>
<DOCNO> 120656 </DOCNO>
What Fraction of Gravitational Lens Galaxies Lie in Groups?


  We predict how the observed variations in galaxy populations with environment
affect the number and properties of gravitational lenses in different
environments. Two trends dominate: lensing strongly favors early-type galaxies,
which tend to lie in dense environments, but dense environments tend to have a
larger ratio of dwarf to giant galaxies than the field. The two effects nearly
cancel, and the distribution of environments for lens and non-lens galaxies are
not substantially different (lens galaxies are slightly less likely than
non-lens galaxies to lie in groups and clusters). We predict that about 20% of
lens galaxies are in bound groups (defined as systems with a line-of-sight
velocity dispersion sigma in the range 200 < sigma < 500 km/s), and another
roughly 3% are in rich clusters (sigma > 500 km/s). Therefore at least roughly
25% of lenses are likely to have environments that significantly perturb the
lensing potential. If such perturbations do not significantly increase the
image separation, we predict that lenses in groups have a mean image separation
that is about 0.2'' smaller than that for lenses in the field and estimate that
20-40 lenses in groups are required to test this prediction with significance.
The tail of the distribution of image separations is already illuminating.
Although lensing by galactic potential wells should rarely produce lenses with
image separations theta >~ 6'', two such lenses are seen among 49 known lenses,
suggesting that environmental perturbations of the lensing potential can be
significant. Further comparison of theory and data will offer a direct probe of
the dark halos of galaxies and groups and reveal the extent to which they
affect lensing estimates of cosmological parameters.

</DOC>
<DOC>
<DOCNO> 72256 </DOCNO>
Observed Property of sigma-Meson and Chiral Symmetry


  The phenomenologically observed property of sigma(600) in our recent analyses
of various pi pi-scattering and -production processes is reviewed and compared
with the prediction of SU(2) linear sigma model. Furthermore, a possibility of
the scalar sigma-nonet (sigma (600), kappa (900), f_0(980) and a_0(980))
forming with the pseudoscalar pi-nonet a linear representation of SU(3) chiral
symmetry is investigated. The origin of repulsive background phase shift
delta_BG, which is essential to lead us to the sigma-existence in our phase
shift analysis, is shown to come from the repulsive lambda phi^4 interaction.

</DOC>
<DOC>
<DOCNO> 170569 </DOCNO>
Information and noise in photon entanglement


  By using finite resolution measurements it is possible to simultaneously
obtain noisy information on two non-commuting polarization components of a
single photon. This method can be applied to a pair of entangled photons with
polarization statistics that violate Bell's inequalities. The theoretically
predicted results show that the non-classical nature of entanglement arises
from negative joint probabilities for the non-commuting polarization
components. These negative probabilities allow a "disentanglement" of the
statistics, providing new insights into the non-classical properties of quantum
information.

</DOC>
<DOC>
<DOCNO> 12817 </DOCNO>
Nodal quasi-particles and coexisting orders in striped superconductors


  We study the properties of a quasi-one dimensional superconductor which
consists of an alternating array of two inequivalent chains. This model is a
simple charicature of a locally striped high temperature superconductor, and is
more generally a theoretically controllable system in which the superconducting
state emerges from a non-Fermi liquid normal state. Even in this limit,
``d-wave like'' order parameter symmetry is natural, but the superconducting
state can either have a complete gap in the quasi-particle spectrum, or gapless
``nodal'' quasiparticles. We also find circumstances in which antiferromagnetic
order (typically incommensurate) coexists with superconductivity.

</DOC>
<DOC>
<DOCNO> 120740 </DOCNO>
Spatially Resolved Circumstellar Structure of Herbig Ae/Be Stars in the


  We have conducted the first systematic study of Herbig Ae/Be stars using the
technique of long baseline stellar interferometry in the near-infrared. The
principal result of this paper is that the IOTA interferometer resolves the
source of infrared excess in 11 of the 15 systems surveyed.
  The visibility data for all the sources has been interpreted within the
context of four simple models which represent a range of plausible
representations for the brightness distribution of the source of excess
emission: a Gaussian, a narrow uniform ring, a flat blackbody disk with a
single temperature power law, and an infrared companion. We find that the
characteristic sizes of the near-infrared emitting regions are larger than
previously thought (0.5-5.9 AU, as given by the FWHM of the Gaussian
intensity). A further major result of this paper is that the sizes measured,
when combined with the observed spectral energy distributions, essentially rule
out accretion disk models represented by blackbody disks with the canonical
radial temperature law with exponent -3/4. We also find that, within the range
observed in this study, none of the sources (except the new binary) shows
varying visibilities as the orientation of the interferometer baseline changes.
  Taken as an ensemble, with no clear evidence in favor of axi-symmetric
structure, the observations favor the interpretation that the circumstellar
dust is distributed in spherical envelopes (the Gaussian model) or thin shells
(the ring model).

</DOC>
<DOC>
<DOCNO> 13209 </DOCNO>
Paramagnetic-diamagnetic interplay in quantum dots for non-zero


  In the usual Fock-and Darwin-formalism with parabolic potential characterized
by the confining energy $\eps_o := \hbar\omega_o= 3.37$ meV, but including
explicitly also the Zeeman coupling between spin and magnetic field, we study
the combined orbital and spin magnetic properties of quantum dots in a
two-dimensional electron gas with parameters for GaAs, for N =1 and N >> 1
electrons on the dot.
  For N=1 the magnetization M(T,B) consists of a paramagnetic spin contribution
and a diamagnetic orbital contribution, which dominate in a non-trivial way at
low temperature and fields rsp. high temperature and fields.
  For N >> 1, where orbital and spin effects are intrinsically coupled in a
subtle way and cannot be separated, we find in a simplified Hartree
approximation that at N=m^2, i.e. at a half-filled last shell, M(T,B,N) is
parallel (antiparallel) to the magnetic field, if temperatures and fields are
low enough (high enough), whereas for N\ne m^2 the magnetization oscillates
with B and N as a T-dependent periodic function of the variable
x:=\sqrt{N}eB/(2m^*c\omega_o), with T-independent period \Delta x =1 (where m^*
:= 0.067 m_o is the small effective mass of GaAs, while m_o is the electron
mass). Correspondingly, by an adiabatic demagnetization process, which should
only be fast enough with respect to the slow transient time of the magnetic
properties of the dot, the temperature of the dot diminishes rsp. increases
with decreasing magnetic field, and in some cases we obtain quite pronounced
effects.

</DOC>
<DOC>
<DOCNO> 70273 </DOCNO>
Do electroweak precision data and Higgs-mass constraints rule out a


  We investigate the phenomenological implications of a light scalar bottom
quark, with a mass of about the bottom quark mass, within the minimal
supersymmetric standard model. The study of such a scenario is of theoretical
interest, since, depending on their production and decay modes, light sbottoms
may have escaped experimental detection up to now and, in addition, may
naturally appear for large values of \tan\beta. In this article we show that
such a light sbottom cannot be ruled out by the constraints from the
electroweak precision data and the present bound on the lightest CP-even Higgs
boson mass at LEP. It is inferred that a light sbottom scenario requires in
general a relatively light scalar top quark whose mass is typically about the
top-quark mass. It is also shown that under these conditions the lightest
CP-even Higgs boson decays predominantly into scalar bottom quarks in most of
the parameter space and that its mass is restricted to m_h ~< 123 GeV.

</DOC>
<DOC>
<DOCNO> 117598 </DOCNO>
The INT Wide Field Imaging Survey(WFS)


  The 2.5m Isaac Newton Telescope(INT) is currently being used to carry out a
major multi-colour, multi-epoch, CCD based wide field survey over an area of
100 square degrees. The survey parameters have been chosen to maximise
scientific return over a wide range of scientific areas and to complement other
surveys being carried out elsewhere. Unique aspects of the survey is that it
concentrates on regions of sky that are easily accessible from telescopes in
both Northern and Southern terrestrial hemispheres and that it the first public
survey to use filters similar to that being used by the Sloan Digital Sky
Survey. A major aim of the the INT Wide Field Survey program is to bridge the
gap between the all-sky photographic 2 and 3 band surveys such as the Palomar
and UK Schmidt sky surveys and the ultra-deep keyhole surveys such as the
Hubble Deep Field.

</DOC>
<DOC>
<DOCNO> 121386 </DOCNO>
Hydrodynamic approach to the evolution of cosmological structures


  A hydrodynamic formulation of the evolution of large-scale structure in the
Universe is presented. It relies on the spatially coarse-grained description of
the dynamical evolution of a many-body gravitating system. Because of the
assumed irrelevance of short-range (``collisional'') interactions, the way to
tackle the hydrodynamic equations is essentially different from the usual case.
The main assumption is that the influence of the small scales over the
large-scale evolution is weak: this idea is implemented in the form of a
large-scale expansion for the coarse-grained equations. This expansion builds a
framework in which to derive in a controlled manner the popular ``dust'' model
(as the lowest-order term) and the ``adhesion'' model (as the first-order
correction). It provides a clear physical interpretation of the assumptions
involved in these models and also the possibility to improve over them.

</DOC>
<DOC>
<DOCNO> 121632 </DOCNO>
Steady-state conduction-driven temperature profile in clusters of


  The temperature profile (TP) of the intracluster medium (ICM) is of primeval
importance for deriving the dynamical parameters of the largest equilibrium
systems known in the universe, in particular their total mass profile.
Analytical models of the ICM often assume that the ICM is isothermal or
parametrize the TP with a polytropic index. This parameter is ajusted to
observations, but has in fact poor physical meaning for values other than 1 or
5/3, when considering monoatomic gases. In this article, I present a
theoretical model of a relaxed cluster where the TP is instead structured by
electronic thermal conduction. Neglecting cooling and heating terms, the
stationnary energy conservation equation reduces to a 2nd order differential
equation, whose resolution requires two boundary conditions, taken here as the
inner radius and the ratio between inner and outer temperature. Once these two
constants are chosen, the TP has a fixed analytical expression, which
reproduces nicely the observed ``universal'' TP obtained by Markevitch et al.
(1998) from ASCA data. Using observed X-ray surface brightnesses for two hot
clusters with spatially resolved TP, the local polytropic index and the hot gas
fraction profile are predicted and compare very well with ASCA observations
(Markevitch et al 1999). Moreover, the total density profile derived from
observed X-ray surface brightness, hydrostatic equilibrium and the
conduction-driven TP is very well fit by three analytical profiles found to
describe the structure of galactic or cluster halos in numerical simulations of
collisionless matter (Hernquist, 1991; Navarro et al. 1995, 1997; Burkert
1995). (abriged)

</DOC>
<DOC>
<DOCNO> 72263 </DOCNO>
Chiral-odd distribution functions in the chiral quark soliton model


  The recent measurements of azimuthal single spin asymmetries by the HERMES
collaboration has opened up new possibility to measure chiral-odd distribution
functions through semi-inclusive deep-inelastic scatterings. Here, predictions
are given for the twist-2 and twist-3 chiral-odd distribution functions of the
nucleon within the framework of the chiral quark soliton model, with full
inclusion of the vacuum polarization effects as well as the subleading $1/N_c$
corrections. The importance of the vacuum polarization effects is demonstrated
by showing that the so-called Soffer inequality holds not only for the quark
distributions but also for the antiquark ones.

</DOC>
<DOC>
<DOCNO> 68388 </DOCNO>
A Light Sterile Neutrino in the TopFlavor Model


  A scenario based on the TopFlavor model is presented to explain the origin of
a light sterile neutrino as indicated by all combined neutrino oscillation
experiments. The model is phenomenologically well motivated and compatible with
all available low-energy data. The derived nuetrino mass matrix can
qualitatively explain the observed hierarchy in the neutrino mass splittings as
indicated by the neutrino oscillation data. Numerical results are obtained for
special cases.

</DOC>
<DOC>
<DOCNO> 71865 </DOCNO>
Cumulant ratios in fully developed turbulence


  In the context of random multiplicative cascade processes, we derive
analytical solutions for one- and two-point cumulants with restored
translational invariance. On taking ratios of cumulants in ln epsilon,
geometrical effects due to spatial averaging cancel out. These ratios can
successfully distinguish between splitting functions while multifractal scaling
exponents and multiplier distributions cannot.

</DOC>
<DOC>
<DOCNO> 69258 </DOCNO>
D-Branes at Singularities : A Bottom-Up Approach to the String Embedding


  We propose a bottom-up approach to the building of particle physics models
from string theory. Our building blocks are Type II D-branes which we combine
appropriately to reproduce desirable features of a particle theory model: 1)
Chirality ; 2) Standard Model group ; 3) N=1 or N=0 supersymmetry ; 4) Three
quark-lepton generations. We start such a program by studying configurations of
D=10, Type IIB D3-branes located at singularities. We study in detail the case
of Z_N, N=1,0 orbifold singularities leading to the SM group or some left-right
symmetricextension. In general, tadpole cancellation conditions require the
presence of additional branes, e.g. D7-branes. For the N=1 supersymmetric case
the unique twist leading to three quark-lepton generations is Z_3, predicting
$\sin^2\theta_W=3/14=0.21$. The models obtained are the simplest semirealistic
string models ever built. In the non-supersymmetric case there is a
three-generation model for each Z_N, N>4, but the Weinberg angle is in general
too small. One can obtain a large class of D=4 compact models by considering
the above structure embedded into a Calabi Yau compactification. We explicitly
construct examples of such compact models using Z_3 toroidal orbifolds and
orientifolds, and discuss their properties. In these examples, global
cancellation of RR charge may be achieved by adding anti-branes stuck at the
fixed points, leading to models with hidden sector gravity-induced
supersymmetry breaking. More general frameworks, like F-theory
compactifications, allow completely $\NN=1$ supersymmetric embeddings of our
local structures, as we show in an explicit example.

</DOC>
<DOC>
<DOCNO> 85091 </DOCNO>
Microcanonical statistics of black holes and bootstrap condition


  The microcanonical statistics of the Schwarzschild black holes as well as the
Reissner-Nordstr$\sf \ddot{o}$m black holes are analyzed. In both cases we set
up the inequalities in the microcanonical density of states.
  These are then used to show that the most probable configuration in the gases
of black holes is that one black hole acquires all of the mass and all of the
charge at high energy limit. Thus the black holes obey the statistical
bootstrap condition and, in contrast to the other investigation, we see that
U(1) charge does not break the bootstrap property.

</DOC>
<DOC>
<DOCNO> 69691 </DOCNO>
Diffractive $\phi$ Production in a Perturbative QCD Model


  The elastic leptoproduction of $\phi$ measured by the H1 collaboration at
HERA is described by a perturbative QCD model, based on open $s\bar{s}$
production and parton hadron duality, proposed by Martin et al. We observe that
both the total cross section and the ratio of the longitudinal and transverse
cross sections are well reproduced with an effective strange-quark mass $m_s
\sim 320- 380 $ MeV for various gluon distribution functions. Possible
connection of the effective mass and the momentum dependent dynamical mass
associated with dynamical breaking of chiral symmetry is also discussed.

</DOC>
<DOC>
<DOCNO> 102439 </DOCNO>
Geometric Meanings of Curvatures in Finsler Geometry


  In Finsler geometry, we use calculus to study the geometry of regular inner
metric spaces. In this note I will briefly discuss various curvatures and their
geometric meanings from the metric geometry point of view, without going into
the forest of tensors.

</DOC>
<DOC>
<DOCNO> 120168 </DOCNO>
Spectroscopic Gravitational Lens Candidates in the CNOC2 Field Galaxy


  We present five candidate gravitational lenses discovered spectroscopically
in the Canadian Network for Observational Cosmology Field Galaxy Redshift
Survey (CNOC2), along with one found in followup observations. Each has a
secure redshift based on several features, plus a discrepant emission line
which does not match any known or plausible feature and is visible in multiple
direct spectral images. We identify these lines as Lyman-alpha or [OII]
emission from galaxies lensed by, or projected onto, the CNOC2 target galaxies.
Einstein radii estimated from the candidate deflector galaxy luminosities
indicate that for two candidates the lines are probably [OII] from projected
z<1 galaxies (consistent with the detection of H-beta as well as [OII] in one
of them), but that in the remaining four cases the lines could be Ly-alpha from
lensed z>3 galaxies. We estimate that only 1.9+-0.7 [OII]-emitting galaxies are
expected to project onto target galaxies in the original CNOC2 sample,
consistent with three or four of the six candidates being true gravitational
lenses.

</DOC>
<DOC>
<DOCNO> 119144 </DOCNO>
Network and Internetwork: a compared Multiwavelength Analysis


  We analyze the temporal behavior of Network Bright Points (NBPs), present in
the solar atmosphere, using a set of data acquired during coordinated
observations between ground-based observatories (mainly at the NSO/Sacramento
Peak) and the Michelson Doppler Interferometer onboard SOHO. We find that, at
any time during the observational sequence, all the NBPs visible in the NaD2
images are co-spatial within 1 arcsec with locations of enhanced magnetic
field. In analogy with the Ca II K line, the NaD2 line center emission can be
used as a proxy for magnetic structures. We also compare the oscillation
properties of NBPs and internetwork areas. At photospheric levels no
differences between the two structures are found in power spectra, but analysis
of phase and coherence spectra suggests the presence of downward propagating
waves in the internetwork. At chromospheric levels some differences are evident
in the power spectrum between NBPs and internetwork. The power spectrum of NBPs
at the Halpha core wavelength shows an important peak at 2.2 mHz (7 minutes),
not present in the internetwork areas. Its coherence spectrum with Halpha wings
shows very low coherence at this frequency, implying that the oscillations at
these chromospheric levels are not directly coupled with those present in lower
layers.

</DOC>
<DOC>
<DOCNO> 100807 </DOCNO>
Kodaira dimension of symmetric powers


  In this short note, we determine the Kodaira dimension and some of the
plurigenera of (a desingularization of) a symmetric power of a smooth
projective variety. We use it to obtain bounds on the genus of curve passing
through a fixed number of general points.

</DOC>
<DOC>
<DOCNO> 10686 </DOCNO>
Nontopological Finite Temperature Induced Fermion Number


  We show that while the zero temperature induced fermion number in a chiral
sigma model background depends only on the asymptotic values of the chiral
field, at finite temperature the induced fermion number depends also on the
detailed shape of the chiral background. We resum the leading low temperature
terms to all orders in the derivative expansion, producing a simple result that
can be interpreted physically as the different effect of the chiral background
on virtual pairs of the Dirac sea and on the real particles of the thermal
plasma. By contrast, for a kink background, not of sigma model form, the finite
temperature induced fermion number is temperature dependent but topological.

</DOC>
<DOC>
<DOCNO> 122352 </DOCNO>
Signature of the solar cycle in the low degree p-modes using Mark-I


  High quality observations of the low degree p-modes exist for almost two
complete solar cycles using the solar spectrophotometer Mark-I, located and
operating at the Observatorio del Teide (Tenerife, Spain). In this work, the
observations available have been re-analyzed over a much wider time interval
than before. We analyze the time variation of the yearly frequency shift and
its frequency dependence. This information will be used in order to average
annual power spectra by removing the effect of the solar cycle. Using this
average power spectrum, a new estimate of the rotational splittings is
attempted.

</DOC>
<DOC>
<DOCNO> 12008 </DOCNO>
Determining bottom price-levels after a speculative peak


  During a stock market peak the price of a given stock ($ i $) jumps from an
initial level $ p_1(i) $ to a peak level $ p_2(i) $ before falling back to a
bottom level $ p_3(i) $. The ratios $ A(i) = p_2(i)/p_1(i) $ and $ B(i)=
p_3(i)/p_1(i) $ are referred to as the peak- and bottom-amplitude respectively.
The paper shows that for a sample of stocks there is a linear relationship
between $ A(i) $ and $ B(i) $ of the form: $ B=0.4A+b $. In words, this means
that the higher the price of a stock climbs during a bull market the better it
resists during the subsequent bear market. That rule, which we call the
resilience pattern, also applies to other speculative markets. It provides a
useful guiding line for Monte Carlo simulations.

</DOC>
<DOC>
<DOCNO> 8365 </DOCNO>
Effect of phase fluctuations on INS and NMR experiments in the


  We present a theory for inelastic neutron scattering (INS) and nuclear
magnetic resonance (NMR) experiments in the pseudo-gap regime of the underdoped
high-$T_c$ cuprates. We show that superconducting phase fluctuations greatly
affect the temperature and frequency dependence of the spin-susceptibility,
$\chi''$, probed by both experimental techniques. This result explains the
appearance of a {\it resonance peak}, observed in INS experiments, below a
temperature $T_0 > T_c$. In the same temperature regime, we find that the
$^{63}$Cu spin-lattice relaxation rate, $1/T_1$, measured in NMR experiments,
is suppressed. Our results are in qualitative agreement with the available
experimental data.

</DOC>
<DOC>
<DOCNO> 170744 </DOCNO>
Coherent Mechanism of Robust Population Inversion


  A coherent mechanism of robust population inversion in atomic and molecular
systems by a chirped field is presented. It is demonstrated that a field of
sufficiently high chirp rate imposes a certain relative phase between a ground
and excited state wavefunction of a two-level system. The value of the relative
phase angle is thus restricted to be negative and close to 0 or $-\pi$ for
positive and negative chirp, respectively. This explains the unidirectionality
of the population transfer from the ground to the excited state. In a molecular
system composed of a ground and excited potential energy surface the symmetry
between the action of a pulse with a large positive and negative chirp is
broken. The same framwork of the coherent mechanism can explain the symmetry
breaking and the population inversion due to a positive chirped field.

</DOC>
<DOC>
<DOCNO> 121000 </DOCNO>
Atomic and Molecular Gas near NGC3077: The Making of a New Dwarf Galaxy?


  Using the IRAM 30m radio telescope we have mapped the tidal arm feature
south-east of NGC 3077 where we recently detected molecular gas in the CO (1-0)
and (2-1) transitions. We find that the molecular gas is much more extended
than previously thought (several kpc). The CO emission can be separated into at
least 3 distinct complexes with equivalent radii between 250pc and 700pc - the
newly detected complexes therefore range among the largest molecular complexes
in the local universe. Mass estimates based on virialization and employing an
X_CO factor yield a total mass for the complexes of order 4 x 10^7 M_sun, i.e.
more than the estimated molecular mass within NGC 3077 itself. This implies
that interactions between galaxies can efficiently remove heavy elements and
molecules from a galaxy and enrich the intergalactic medium. A comparison of
the distribution of HI and CO shows no clear correlation. However, CO is only
found in regions where the HI column density exceeds 1.1 x 10^21 cm^-2. HI
masses for the molecular complexes mapped are of the same order as the
corresponding molecular masses. Since the complexes have all the ingredients to
form stars in the future, we are thus presumably witnessing the birth of a
dwarf galaxy. This process may have dominated the creation of dwarf galaxies at
larger look-back times.

</DOC>
<DOC>
<DOCNO> 71620 </DOCNO>
"Neutrinoless Double Beta Decay" at a Neutrino Factory


  We examine the prospects of detecting an analogous process of neutrinoless
double beta decay at a neutrino factory from a high energy muon storage ring.
Limits from LEP experiments, neutrinoless double beta decay as well as from
global fits have to be incorporated and severely restrict the results. We
investigate what limits on light and heavy effective Majorana neutrino masses
can be obtained and compare them with existing ones. Discussed are also
contributions from right-handed neutrinos and purely right-handed interactions.
Other ``new physics'' contributions to the same final state might produce large
event numbers.

</DOC>
<DOC>
<DOCNO> 123040 </DOCNO>
Neutralino Dark Matter and Caustic Ring Signals


  We have studied the effects on the gamma-ray flux on Earth by neutralino
annihilations in caustic rings of dark matter in the Galactic halo. The caustic
ring model by Sikivie has been used where dark matter particles are assumed to
possess angular momentum with respect to the Galactic centre. The computer code
DarkSUSY was then used to examine the supersymmetric implications on the flux.
We conclude that a small signal might be detectable under very optimistic
assumptions, but under these only.

</DOC>
<DOC>
<DOCNO> 8588 </DOCNO>
Macroscopic Quantum Coherence in a Magnetic Nanoparticle Above the


  We study macroscopic quantum tunneling of the magnetic moment in a
single-domain particle placed above the surface of a superconductor. Such a
setup allows one to manipulate the height of the energy barrier, preserving the
degeneracy of the ground state. The tunneling amplitude and the effect of the
dissipation in the superconductor are computed.

</DOC>
<DOC>
<DOCNO> 11764 </DOCNO>
Phase diagram of a generalized Hubbard model applied to orbital order in


  The magnetic phase diagram of a two-dimensional generalized Hubbard model
proposed for manganites is studied within Hartree-Fock approximation. In this
model the hopping matrix includes anisotropic diagonal hopping matrix elements
as well as off-diagonal elements. The antiferromagnetic (AF), ferromagnetic
(F), canted (C) and paramagnetic (P) states are included in the analysis as
possible phases. It is found that away from half-filling only the canted and F
states may exist and AF and P states which are possible for the usual Hubbard
model do not appear. This is because the F order has already developed for
on-site repulsion U=0 due to the hopping matrix of the generalized model. When
applied for manganites the orbital degree is described by a pseudospin. Thus
our ``magnetic'' phase diagram obtained physically describes how orbital order
changes with $U$ and with doping for manganites. Part of our results are
consistent with other numerical calculations and some experiments.

</DOC>
<DOC>
<DOCNO> 170354 </DOCNO>
Control of open quantum systems dynamics


  We investigate the control resources needed to effect arbitrary quantum
dynamics. We show that the ability to perform measurements on a quantum system,
combined with the ability to feed back the measurement results via coherent
control, allows one to control the system to follow any desired open-system
evolution. Such universal control can be achieved, in principle, through the
repeated application of only two coherent control operations and a simple
``Yes-No'' measurement.

</DOC>
<DOC>
<DOCNO> 12332 </DOCNO>
Theory of superconductor with kappa close to 1/sqrt{2}


  As was firstly shown by E. Bogomolny, the critical Ginzburg-Landay (GL)
parameter kappa =1/sqrt{2} at which a superconductor changes its behavior from
type-I to type-II, is the special highly degenerate point where Abrikosov
vortices do not interact and therefore all vortex states have the same energy.
Developing a secular perturbation theory we studied how this degeneracy is
lifted when kappa is slightly different from 1\sqrt{2} or when the GL theory is
extended to the higher in T-Tc terms. We constructed a simple secular
functional, that depends only on few experimentally measurable phenomenological
parameters and therefore is quite efficient to study the vortex state of
superconductor in this transitional region of kappa. Basing on this, we
calculated such vortex state properties as: critical fields, energy of the
normal-superconductor interface, energy of the vortex lattice, vortex
interaction energy etc. and compared them with previous results that were based
on bulky solutions of GL equations.

</DOC>
<DOC>
<DOCNO> 9190 </DOCNO>
Possible scenario of the spatially separated Fermi-Bose mixture in the


  A new scenario for superconductivity in the bismuthates based on the concept
of a spatially separated Fermi-Bose mixture is proposed. In the framework of
this scenario we qualitatively explain the insulator-metal transition and the
nature of the superconductivity which occur in Ba_{1-x}K_xBiO_3 under doping by
K. We also analyze briefly an applicability of this scenario for the high-Tc
superconductors. In conclusion some additional experiments required to
elucidate more precisely the nature of the superconductivity in the bismuthates
are discussed.

</DOC>
<DOC>
<DOCNO> 69166 </DOCNO>
Many-body theory interpretation of deep inelastic scattering


  We analyze data on deep inelastic scattering of electrons from the proton
using ideas from standard many-body theory involving {\em bound} constituents
subject to {\em interactions}. This leads us to expect, at large three-momentum
transfer ${\bf{q}}$, scaling in terms of the variable $\tilde{y}=\nu-{\bf
|q|}$. The response at constant ${\bf |q|}$ scales well in this variable.
Interaction effects are manifestly displayed in this approach. They are
illustrated in two examples.

</DOC>
<DOC>
<DOCNO> 100592 </DOCNO>
Scalar Levin-Type Sequence Transformations


  Sequence transformations are important tools for the convergence acceleration
of slowly convergent scalar sequences or series and for the summation of
divergent series. Transformations that depend not only on the sequence elements
or partial sums $s_n$ but also on an auxiliary sequence of so-called remainder
estimates $\omega_n$ are of Levin-type if they are linear in the $s_n$, and
nonlinear in the $\omega_n$. Known Levin-type sequence transformations are
reviewed and put into a common theoretical framework. It is discussed how such
transformations may be constructed by either a model sequence approach or by
iteration of simple transformations. As illustration, two new sequence
transformations are derived. Common properties and results on convergence
acceleration and stability are given. For important special cases, extensions
of the general results are presented. Also, guidelines for the application of
Levin-type sequence transformations are discussed, and a few numerical examples
are given.

</DOC>
<DOC>
<DOCNO> 10726 </DOCNO>
Transport in hybrid electronic devices based on a modified DNA


  We report on a new class of hybrid electronic devices based on a DNA
nucleoside (deoxyguanosine lipophilic derivative) whose assembled polymeric
ribbons interconnect a submicron metallic gate. The device exhibits large
conductivity at room temperature, rectifying behaviour and strong
current-voltage hysteresis. The transport mechanism through the molecules is
investigated by comparing films with different self-assembling morphology. We
found that the main transport mechanism is connected to pi-pi interactions
between guanosine molecules in adjacent ribbons, consistently with the results
of our first-principles calculations.

</DOC>
<DOC>
<DOCNO> 10771 </DOCNO>
Theory of coherent photoassociation of a Bose-Einstein condensate


  We study coherent photoassociation, phenomena analogous to coherent optical
transients in few-level systems, which may take place in photoassociation of an
atomic Bose-Einstein condensate but not in a nondegenerate gas. We develop a
second-quantized Hamiltonian to describe photoassociation, and apply the
Hamiltonian both in the momentum representation and in the position
representation (field theory). Solution of the two-mode problem including only
one mode each for the atomic and molecular condensates displays analogs of Rabi
oscillations and rapid adiabatic passage. A classical version of the field
theory for atoms and molecules is used to demonstrate that, in the presence of
photoassociating light, a joint-atom molecule is unstable against growth of
density fluctuations. Experimental complications, including spontaneous
emission and unwanted "rogue" photodissociation from a photoassociated molecule
are analyzed. A two-color Raman scheme is studied as a method to set up an
effective two-mode scheme with reduced spontaneous emission losses. We discuss
photoassociation rates and photoassociation Rabi frequencies for high-lying
vibrational states in alkalis both on the basis of molecular-structure
calculations, and by comparing with an experiment [Wynar et al., Science 287,
1016 (2000)].

</DOC>
<DOC>
<DOCNO> 69946 </DOCNO>
A Phenomenological Estimate of the Binding Energy of Heavy Dimesons


  A phenomenological estimate is derived such that the binding energies of
dimesons are expressed as combinations of masses of different mesons and
baryons. The estimate is almost model-independent, the only major assumptions
being that the wave functions of the two light quarks in $\Lambda_c$,
$\Lambda_b$ and in the $\bar{c}\bar{c}qq$ and $\bar{b}\bar{b}qq$ dimesons are
very similar, and that for heavy quarks the $QQ$ interaction is half as strong
as the $Q\bar{Q}$ interaction. We get $\bar{b}\bar{b}qq$ (I=0, J=1) bound by
about 100 MeV and $\bar{c}\bar{c}qq$ unbound.

</DOC>
<DOC>
<DOCNO> 169570 </DOCNO>
Hardy-type experiment for the maximally entangled state: Illustrating


  By selecting a certain subensemble of joint detection events in a
two-particle interferometer arrangement, a formal nonlocality contradiction of
the Hardy type is derived for an ensemble of particle pairs configured in the
maximally entangled state. It is argued, however, that the class of experiments
exhibiting this kind of contradiction does not rule out the assumption of local
realism.

</DOC>
<DOC>
<DOCNO> 8642 </DOCNO>
Series expansions for lattice Green functions


  Lattice Green functions appear in lattice gauge theories, in lattice models
of statistical physics and in random walks. Here, space coordinates are treated
as parameters and series expansions in the mass are obtained. The singular
points in arbitrary dimensions are found. For odd dimensions these are branch
points with half odd-integer exponents, while for even dimensions they are of
the logarithmic type. The differential equations for one, two and three
dimensions are derived, and the general form for arbitrary dimensions is
indicated. Explicit series expressions are found in one and two dimensions.
These series are hypergeometric functions. In three and higher dimensions the
series are more complicated. Finally an algorithmic method by Vohwinkel,
Luscher and Weisz is shown to generalize to arbitrary anisotropies and mass.

</DOC>
<DOC>
<DOCNO> 122399 </DOCNO>
Evidence for Inconsistencies in Galaxy Luminosity Functions Defined by


  Galaxy morphological and spectroscopic types should be nearly independent of
apparent magnitude in a local, magnitude-limited sample. Recent luminosity
function surveys based on morphological classification of galaxies are
substantially more successful at passing this test than surveys based on
spectroscopic classifications. Among spectroscopic classifiers, those defined
by small aperture fibers (ESP, LCRS) show far stronger systematic
classification biases than those defined by large apertures (APM). This effect
can be easily explained as an aperture bias, whereby galaxies with globally
late-type spectra are assigned earlier spectral types which depend on the
redshift and luminosity of the galaxy. The effect is demonstrated by extracting
successively larger aperture spectra from long-slit spectroscopy of nearby
galaxies. This systematic classification bias is generic, and the 2dFGRS and
SDSS surveys will show similar systematic biases in their spectral types. We
suggest several methods for correcting the problem or avoiding it altogether.
If not corrected, this aperture bias can mimic galaxy evolutionary effects and
distort estimates of the luminosity function.

</DOC>
<DOC>
<DOCNO> 80928 </DOCNO>
Pad\'e-Z$_2$ stochastic estimator of determinants applied to quark loop


  We use the Pad\'e-Z$_2$ stochastic estimator for calculating Tr log M to
compute quark loop corrections to quenched QCD. We examine the main source of
error in this technique and look at a way of controlling it.

</DOC>
<DOC>
<DOCNO> 118469 </DOCNO>
Surface Tension between Kaon Condensate and Normal Nuclear Matter Phase


  We calculate for the first time the surface tension and curvature coefficient
of a first order phase transition between two possible phases of cold nuclear
matter, a normal nuclear matter phase in equilibrium with a kaon condensed
phase, at densities a few times the saturation density. We find the surface
tension is proportional to the difference in energy density between the two
phases squared. Furthermore, we show the consequences for the geometrical
structures of the mixed phase region in a neutron star.

</DOC>
<DOC>
<DOCNO> 151694 </DOCNO>
Gauge Dual and Noncommutative Extension of an N=2 Supergravity Solution


  We investigate some properties of a recent supergravity solution of Pilch and
Warner, which is dual to the N=4 gauge theory softly broken to N=2. We verify
that a D3-brane probe has the expected moduli space and its effective action
can be brought to N=2 form. The kinetic term for the probe vanishes on an
enhancon locus, as in earlier work on large-n N=2 theories, though for the
Pilch-Warner solution this locus is a line rather than a ring. On the gauge
theory side we find that the probe metric can be obtained from a perturbative
one-loop calculation; this principle may be useful in obtaining the
supergravity dual at more general points in the N=2 gauge theory moduli space.
We then turn on a B-field, following earlier work on the N=4 theory, to obtain
the supergravity dual to the noncommutative N=2 theory.

</DOC>
<DOC>
<DOCNO> 40091 </DOCNO>
The Case for a 500 GeV e+e- Linear Collider


  Several proposals are being developed around the world for an e+e- linear
collider with an initial center of mass energy of 500 GeV. In this paper, we
will discuss why a project of this type deserves priority as the next major
initiative in high energy physics.

</DOC>
<DOC>
<DOCNO> 117209 </DOCNO>
Coulomb Interaction Does Not Spread Instantaneously


  The experiment is described which shows that Coulomb interaction spreads with
a limit velocity and thus this kind of interaction cannot be considered as so
called "instantaneous action at a distance".

</DOC>
<DOC>
<DOCNO> 12571 </DOCNO>
Adsorption and two-body recombination of atomic hydrogen on


  We present the first systematic measurement of the binding energy $E_a$ of
hydrogen atoms to the surface of saturated $^3$He-$^4$He mixture films. $E_a$
is found to decrease almost linearly from 1.14(1) K down to 0.39(1) K, when the
population of the ground surface state of $^3$He grows from zero to
$6\times10^{14}$ cm$^{-2}$, yielding the value $1.2(1)\times 10^{-15}$ K cm$^2$
for the mean-field parameter of H-$^3$He interaction in 2D. The experiments
were carried out with overall $^3$He concentrations ranging from 0.1 ppm to 5 %
as well as with commercial and isotopically purified $^4$He at temperatures
70...400 mK. Measuring by ESR the rate constants $K_{aa}$ and $K_{ab}$ for
second-order recombination of hydrogen atoms in hyperfine states $a$ and $b$ we
find the ratio $K_{ab}/K_{aa}$ to be independent of the $^3$He content and to
grow with temperature.

</DOC>
<DOC>
<DOCNO> 12511 </DOCNO>
Direct Minimization Generating Electronic States with Proper Occupation


  We carry out the direct minimization of the energy functional proposed by
Mauri, Galli and Car to derive the correct self-consistent ground state with
fractional occupation numbers for a system degenerating at the Fermi level. As
a consequence, this approach enables us to determine the electronic structure
of metallic systems to a high degree of accuracy without the aid of level
broadening of the Fermi-distribution function. The efficiency of the method is
illustrated by calculating the ground-state energy of C$_2$ and Si$_2$
molecules and the W(110) surface to which a tungsten adatom is adsorbed.

</DOC>
<DOC>
<DOCNO> 80965 </DOCNO>
Hadron masses from dynamical, non-perturbatively O(a) improved Wilson


  We present results on light hadron masses from simulations of full QCD and
report on experiences in running such simulations on a Hitachi SR8000-F1
supercomputer.

</DOC>
<DOC>
<DOCNO> 69309 </DOCNO>
Validity of the Color Dipole Approximation for Diffractive Production of


  We study the diffractive photo- and leptoproductions of $J / \psi$ and $\psi
'$ on the proton, and examine the validity of the small-size color dipole
approximation to the production of radially excited heavy quarkonium. The
dipole model predicts a small ratio of $\psi '$ to $J / \psi$ photoproduction
cross sections, which does not agree with experimental data. We show that this
discrepancy originates from a large transverse size of $\psi '$ which makes the
convergence of the transverse size expansion questionable, and the calculation
without the dipole approximation turns out to be consistent with the data.
Productions of $\Upsilon '(2S,3S)$ are also discussed, and the dipole
approximation is found to be reasonable for the $\Upsilon$-family.

</DOC>
<DOC>
<DOCNO> 174471 </DOCNO>
UCN Upscattering rates in a molecular deuterium crystal


  A calculation of ultra-cold neutron (UCN) upscattering rates in molecular
deuterium solids has been carried out, taking into account intra-molecular
exictations and phonons. The different moelcular species ortho-D2 (with even
rotational quantum number J) and para-D2 (with odd J) exhibit significantly
different UCN-phonon annihilation cross-sections. Para- to ortho-D2 conversion,
furthermore, couples UCN to an energy bath of excited rotational states without
mediating phonons. This anomalous upscattering mechanism restricts the UCN
lifetime to 4.6 msec in a normal-D2 solid with 33% para content.

</DOC>
<DOC>
<DOCNO> 40438 </DOCNO>
K0sK0s Final State and Glueball Searches and Lambda-Lambdabar Production


  The K0sK0s final state in two-photon collisions is studied with the L3
detector at LEP using data collected at centre-of-mass energies from 91 GeV to
202 GeV. The mass spectrum is dominated by the formation of the f_2'(1525)
tensor meson in the helicity two state. The two-photon width times the
branching ratio is measured to be Gamma_{gamma
gamma}(f_2'(1525))Br(f_2'(1525)->KKbar) = 0.076 +- 0.006 +- 0.011 keV. Clear
evidence for destructive f_2(1270)-a_2(1320) interference is observed. In
addition a clear signal for f_J(1750) is observed. The study of the decay
angular distribution in the 1750 MeV mass region shows that the spin two
helicity two wave is dominant. No signal is observed in the region around 2.2
GeV. The upper limit for the two-photon partial width of the \xi(2230) tensor
glueball candidate of Gamma_{gamma gamma}(\xi(2230))Br(\xi(2230)->K0sK0s)<1.4
eV at 95% C.L. is derived. The production of Lambda-Lambdabar pairs in
two-photon collisions is also studied. The cross section is compared to
quark-diquark model predictions.

</DOC>
<DOC>
<DOCNO> 169971 </DOCNO>
Schrodinger revisited: an algebraic approach


  Starting with the quantum Liouville equation, we write the density operator
as the product of left and right ideals of an operator algebra and find that
the Schrodinger picture may be expressed through two representation independent
algebraic forms in terms of the density and phase operators. These forms are
respectively the continuity equation, which involves the commutator of the
Hamiltonian with the density operator, and an equation for the time development
of the phase operator that involves the anti-commutator of the Hamiltonian with
this density operator. We show that this latter equation plays two important
roles: (i) it expresses the conservation of energy in a system where energy is
well defined and (ii) it provides a simple way to evaluate the gauge changes
that occur in the Aharonov-Bohm, the Aharonov-Casher, and Berry phase effects.
Both these operator (i.e. purely algebraic) equations also allow us to
re-examine the Bohm interpretation, showing that it is in fact possible to
construct Bohm interpretations in representations other than the
x-representation. We discuss the meaning of the Bohm interpretation in the
light of these new results in terms of non-commutative structures and this
enables us to clarify its relation to standard quantum mechanics.

</DOC>
<DOC>
<DOCNO> 8326 </DOCNO>
The Physical Implementation of Quantum Computation


  After a brief introduction to the principles and promise of quantum
information processing, the requirements for the physical implementation of
quantum computation are discussed. These five requirements, plus two relating
to the communication of quantum information, are extensively explored and
related to the many schemes in atomic physics, quantum optics, nuclear and
electron magnetic resonance spectroscopy, superconducting electronics, and
quantum-dot physics, for achieving quantum computing.

</DOC>
<DOC>
<DOCNO> 123248 </DOCNO>
Supernova types and rates


  We review the basic properties of the different supernova types identified in
the current taxonomy, with emphasis on the more recent developments. To help
orienting in the variegate zoo, the optical photometric and spectroscopic
properties of the different supernova types are presented in a number of
summary figures. We also report the latest estimates of the supernova rates and
stress the need for a dedicated effort to measure SN rates at high redshift.

</DOC>
<DOC>
<DOCNO> 9466 </DOCNO>
Critical currents in Josephson junctions, with unconventional pairing


  Phenomenological Ginzburg-Landau theory is used to calculate the possible
spontaneous vortex states that may exist at corner junctions of
$d_{x^2-y^2}+ix$-wave, (where $x=s$ or $x=d_{xy}$) and s-wave superconductors.
We study the magnetic flux and the critical current modulation with the
junction orientation angle $\theta$, the magnitude of the order parameter, and
the magnetic field $H$. It is seen that the critical current $I_c$ versus the
magnetic flux $\Phi$ relation is symmetric / asymmetric for $x=d_{xy}/s$ when
the orientation is exactly such that the lobes of the dominant
$d_{x^2-y^2}$-wave order parameter points towards the two junctions, which are
at right angles for the corner junction. The conclusion is that a measurement
of the $I_c(\Phi)$ relation may distinguish which symmetry ($d_{x^2-y^2}+is$ or
$d_{x^2-y^2}+id_{xy}$) the order parameter has.

</DOC>
<DOC>
<DOCNO> 99840 </DOCNO>
Band description of knots and Vassiliev invariants


  In 1993 K. Habiro defined $C_k$-move of oriented links and around 1994 he
proved that two oriented knots are transformed into each other by $C_k$-moves
if and only if they have the same Vassiliev invariants of order $\leq k-1$. In
this paper we define Vassiliev invariant of type $(k_1,...,k_l)$, and show
that, for $k=k_1+...+k_l$, two oriented knots are transformed into each other
by $C_k$-moves if and only if they have the same Vassiliev invariants of type
$(k_1,...,k_l)$. We introduce a concept ` band description of knots' and give a
diagram-oriented proof of this theorem. When $k_1=...=k_l=1$, the Vassiliev
invariant of type $(k_1,...,k_l)$ coincides with the Vassiliev invariant of
order $\leq l-1$ in the usual sense. As a special case, we have Habiro's
theorem stated above.

</DOC>
<DOC>
<DOCNO> 101661 </DOCNO>
Convergence or generic divergence of Birkhoff normal form


  We prove that Birkhoff normal form of hamiltonian flows at a non-resonant
singular point with given quadratic part are always convergent or generically
divergent. The same result is proved for the normalization mapping and any
formal first integral.

</DOC>
<DOC>
<DOCNO> 69433 </DOCNO>
Predictions for Lepton Flavour Violation in Z decays


  Recent experimental results suggest that the neutrinos of the Standard Model
are massive, though light. Therefore they may mix with each other giving rise
to lepton flavour or even lepton number violating processes, depending on
whether they are Dirac or Majorana particles. Furthermore, the lightness of the
observed neutrinos may be explained by the existence of heavy ones, whose
effects on LFV would be very sizeable. We present an analysis of the effect of
massive neutrinos on flavour-changing decays of the Z boson into leptons, at
the one-loop level, independent of neutrino mass models. Constraints from
present experiments are taken into account.

</DOC>
<DOC>
<DOCNO> 101085 </DOCNO>
Screening effect due to heavy lower tails in one-dimensional parabolic


  We consider the large-time behavior of the solution $u\colon
[0,\infty)\times\Z\to[0,\infty)$ to the parabolic Anderson problem $\partial_t
u=\kappa\Delta u+\xi u$ with initial data $u(0,\cdot)=1$ and non-positive
finite i.i.d. potentials $(\xi(z))_{z\in\Z}$. Unlike in dimensions $d\ge2$, the
almost-sure decay rate of $u(t,0)$ as $t\to\infty$ is not determined solely by
the upper tails of $\xi(0)$; too heavy lower tails of $\xi(0)$ accelerate the
decay. The interpretation is that sites $x$ with large negative $\xi(x)$ hamper
the mass flow and hence screen off the influence of more favorable regions of
the potential. The phenomenon is unique to $d=1$. The result answers an open
question from our previous study \cite{BK00} of this model in general
dimension.

</DOC>
<DOC>
<DOCNO> 12720 </DOCNO>
Current induced switching of magnetic domains to a perpendicular


  In a ferromagnet--normal-metal--ferromagnet trilayer, a current flowing
perpendicularly to the layers creates a torque on the magnetic moments of the
ferromagnets. When one of the contacts is superconducting, the torque not only
favors parallel or antiparallel alignment of the magnetic moments, as is the
case for two normal contacts, but can also favor a configuration where the two
moments are perpendicular. In addition, whereas the conductance for parallel
and antiparallel magnetic moments is the same, signalling the absence of giant
magnetoresistance in the usual sense, the conductance is greater in the
perpendicular configuration. Thus, a negative magnetoconductance is predicted,
in contrast with the usual giant magnetoresistance.

</DOC>
<DOC>
<DOCNO> 117194 </DOCNO>
Atomic antenna mechanism in HHG and ATI


  This paper reviews recent development of the atomic antenna, a theoretical
framework which describes a number of laser-induced multiphoton phenomena in
atoms, in particular in High Harmonic Generation and in Above Threshold
Ionization. The paper presents a progress report made at the conference "Atoms,
molecules and quantum dots in laser fields: fundamental processes", PISA,
Italy, June 12-16, 2000

</DOC>
<DOC>
<DOCNO> 8596 </DOCNO>
Anderson's "Theorem" and Bogoliubov-de Gennes Equations for Surfaces and


  In order to incorporate spatial inhomogeneity due to nonmagnetic impurities,
Anderson [1] proposed a BCS-type theory in which single-particle states in such
an inhomogeneous system are used. We examine Anderson's proposal, in comparison
with the Bogoliubov-de Gennes equations, for the attractive Hubbard model on a
system with surfaces and impurities.
  [1] P. W. Anderson, J. Phys. Chem. Solids {\bf 11}, 26 (1959).

</DOC>
<DOC>
<DOCNO> 40452 </DOCNO>
Vector-to-Pseudoscalar and Meson-to-Baryon Ratios in Hadronic Z Decays


  Mass dependences of the total production rates per hadronic Z decay of all
light-flavour hadrons measured so far at LEP are extrapolated to the zero mass
limit (m=0) using phenomenological laws of hadron production related to the
spin, isospin, strangeness content and mass of the particles. The
vector-to-pseudoscalar and meson-to-baryon ratios at m=0 are found to be: rho^+
/ 3 pi^+ = 1.2 +/- 0.3 and pi^+ / p = 2.9 +/- 0.3, in good agreement with the
predictions of quark combinatorics.

</DOC>
<DOC>
<DOCNO> 85449 </DOCNO>
Inflation on a single brane - exact solutions


  Algorithms are developed for generating a class of exact braneworld
cosmologies, where a self-interacting scalar field is confined to a
positive-tension brane embedded in a bulk containing a negative cosmological
constant. It is assumed that the five-dimensional Planck scale exceeds the
brane tension but is smaller than the four-dimensional Planck mass. It is shown
that the field equations can be expressed as a first-order system. A number of
solutions to the equations of motion are found. The potential resulting in the
perfect fluid model is identified.

</DOC>
<DOC>
<DOCNO> 151418 </DOCNO>
Cohomology in the Pure Spinor Formalism for the Superstring


  A manifestly super-Poincar\'e covariant formalism for the superstring has
recently been constructed using a pure spinor variable. Unlike the covariant
Green-Schwarz formalism, this new formalism is easily quantized with a BRST
operator and tree-level scattering amplitudes have been evaluated in a
manifestly covariant manner.
  In this paper, the cohomology of the BRST operator in the pure spinor
formalism is shown to give the usual light-cone Green-Schwarz spectrum.
Although the BRST operator does not directly involve the Virasoro constraint,
this constraint emerges after expressing the pure spinor variable in terms of
SO(8) variables.

</DOC>
<DOC>
<DOCNO> 121316 </DOCNO>
Spectroscopically Peculiar Type Ia Supernovae and Implications for


  In a recent paper Li et al. (2000) reported that 36 percent of 45 Type Ia
supernovae (SNe Ia) discovered since 1997 in two volume-limited supernova
searches were spectroscopically peculiar, and they suggested that because this
peculiarity rate is higher than that reported for an earlier observational
sample by Branch et al. (1993), it is now more likely that SNe Ia are produced
by more than one kind of progenitor. In this paper I discuss and clarify the
differences between the results of Li et al. and Branch et al. and I suggest
that multiple progenitor systems are now less likely than they were before.

</DOC>
<DOC>
<DOCNO> 9764 </DOCNO>
Reply to the Comment on``Scaling Laws for a System with Long--Range


  The fact that mean field theory is appropriate to describe an Ising model
with long-range interactions has been already shown by Cannas and Tamarit.
Although not explicited in our Letter, we have used periodic boundary
conditions in all our simulations, such that the maximum possible distance
between two lattice sites is L/2.
  We make no specific comments about the validity (or lack of validity) of
Boltzmann-Gibbs statistical mechanics to describe long-range systems. Our paper
does nothing but to compare the scaling functions derived from Boltzman-Gibbs
statistics from those derived from the use of Tsallis entropy.

</DOC>
<DOC>
<DOCNO> 119448 </DOCNO>
Application of the Limit Cycle Model to Star Formation Histories in


  We propose a limit-cycle scenario of star formation history for any
morphological type of spiral galaxies. It is known observationally that the
early-type spiral sample has a wider range of the present star formation rate
(SFR) than the late-type sample. This tendency is understood in the framework
of the limit-cycle model of the interstellar medium (ISM), in which the SFR
cyclically changes in accordance with the temporal variation of the mass
fraction of the three ISM components. When the limit-cycle model of the ISM is
applied, the amplitude of variation of the SFR is expected to change with the
supernova (SN) rate. Observational evidence indicates that the early-type
spiral galaxies show smaller rates of present SN than late-type ones. Combining
this evidence with the limit-cycle model of the ISM, we predict that the
early-type spiral galaxies show larger amplitudes in their SFR variation than
the late-types. Indeed, this prediction is consistent with the observed wider
range of the SFR in the early-type sample than in the late-type sample. Thus,
in the framework of the limit-cycle model of the ISM, we are able to interpret
the difference in the amplitude of SFR variation among the morphological
classes of spiral galaxies.

</DOC>
<DOC>
<DOCNO> 68414 </DOCNO>
Lepton flavor violation in the supersymmetric standard model with


  Lepton flavor violating processes are obtained from the mixing between
ordinary leptons and vectorlike SU(2)_L doublet leptons which may originate in
E_6. The effects of this lepton mixing are, however, suppressed naturally by
the hierarchy of the charged lepton masses. In the supersymmetric model,
significant effects of lepton flavor violation may appear rather through
slepton mixing, which is in the present case generated by radiative corrections
with ordinary-exotic lepton couplings. We are especially interested in the mu
-> e gamma decay. In the model without the bare mass term of vectorlike
leptons, the supersymmetric contributions are rather suppressed due to the
approximate U(1)_e X U(1)_mu. It is, however, remarkable that they are
substantially enhanced by tan^6 beta. Then, B(mu -> e gamma) might be
comparable to the experimental bound for large tan beta. In the model with the
bare mass term, much larger contributions are obtained through slepton mixing.
These investigations show that the supersymmetric effects on lepton flavor
violation due to the vectorlike leptons can be observed in the near future
experiments.

</DOC>
<DOC>
<DOCNO> 101405 </DOCNO>
Planar complex numbers in even n dimensions


  Planar commutative n-complex numbers of the form
u=x_0+h_1x_1+h_2x_2+...+h_{n-1}x_{n-1} are introduced in an even number n of
dimensions, the variables x_0,...,x_{n-1} being real numbers. The planar
n-complex numbers can be described by the modulus d, by the amplitude \rho, by
n/2 azimuthal angles \phi_k, and by n/2-1 planar angles \psi_{k-1}. The
exponential function of a planar n-complex number can be expanded in terms of
the planar n-dimensional cosexponential functions f_{nk}, k=0,1,...,n-1, and
expressions are given for f_{nk}. Exponential and trigonometric forms are
obtained for the planar n-complex numbers. The planar n-complex functions
defined by series of powers are analytic, and the partial derivatives of the
components of the planar n-complex functions are closely related. The integrals
of planar n-complex functions are independent of path in regions where the
functions are regular. The fact that the exponential form of the planar
n-complex numbers depends on the cyclic variables \phi_k leads to the concept
of pole and residue for integrals on closed paths. The polynomials of planar
n-complex variables can always be written as products of linear factors,
although the factorization may not be unique.

</DOC>
<DOC>
<DOCNO> 40330 </DOCNO>
New Measurements of Nucleon Structure Functions from CCFR/NuTeV


  We report on the extraction of the structure functions F_2 and Delta xF_3 =
xF_3nu-xF_3nub from CCFR neutrino-Fe and antineutrino-Fe differential cross
sections. The extraction is performed in a physics model independent (PMI) way.
This first measurement for Delta xF_3, which is useful in testing models of
heavy charm production, is higher than current theoretical predictions. Within
5% the F_2 (PMI) values measured in neutrino and muon scattering are in
agreement with the predictions of Next-to-Leading-Order PDFs (using massive
charm production schemes), thus resolving the long-standing discrepancy between
the two measurements.

</DOC>
<DOC>
<DOCNO> 13216 </DOCNO>
Skyrmions in a ferromagnetic Bose-Einstein condensate


  The recently realized multicomponent Bose-Einstein condensates provide
opportunities to explore the rich physics brought about by the spin degrees of
freedom. For instance, we can study spin waves and phase separation,
macroscopic quantum tunneling, Rabi oscillations, the coupling between spin
gradients and superfluid flow, squeezed spin states, vortices and other
topological excitations. Theoretically, there have been already some studies of
the ground-state properties of these systems and their line-like vortex
excitations. In analogy with nuclear physics or the quantum Hall effect, we
explore here the possibility of observing point-like topological excitations or
skyrmions. These are nontrivial spin textures that in principle can exist in a
spinor Bose-Einstein condensate. In particular, we investigate the stability of
skyrmions in a fictitious spin-1/2 condensate of Rb87 atoms. We find that
skyrmions can exist in this case only as a metastable state, but with a
lifetime of the order of, or even longer than, the typical lifetime of the
condensate itself. In addition to determining the size and the lifetime of the
skyrmion, we also present its spin texture and finally briefly consider its
dynamical properties.

</DOC>
<DOC>
<DOCNO> 11162 </DOCNO>
Correlation Effects on the Double Exchange Model in a Ferromagnetic


  The effect of the Hubbard interaction among conduction electrons on the
double exchange model is investigated in a ferromagnetic metallic phase.
Applying iterative perturbation theory to the Hubbard interaction within
dynamical mean field theory, we calculate the one-particle spectral function
and the optical conductivity, in which coherent-potential approximation is
further used to treat the ferromagnetic Hund coupling between conduction
electrons and localized spins. Identifying the decrease of the magnetization
for the localized spin with the increase of the temperature, we discuss the
temperature dependence of the one-particle spectrum and the optical
conductivity. It is found that the interplay between the Hund coupling and the
Hubbard interaction dramatically changes the spectral function, while it is
somehow obscured in the optical conductivity.

</DOC>
<DOC>
<DOCNO> 68776 </DOCNO>
Higgs sector and R-parity breaking couplings in models with broken


  Four different supersymmetric models based on SU(2)_L X U(1)_R X U(1)_B-L and
SU(2)_L X SU(2)_R X U(1)_B-L gauge symmetry groups are studied. U(1)_B-L
symmetry is broken spontaneously by a vacuum expectation value (VEV) of a
sneutrino field. The right-handed gauge bosons may obtain their mass solely by
sneutrino VEV. The physical charged lepton and neutrino are mixtures of
gauginos, higgsinos and lepton interaction eigenstates. Explicit formulae for
masses and mixings in the physical lepton fields are found. The spontaneous
symmetry breaking mechanism fixes the trilinear R-parity breaking couplings.
Only some special R-parity breaking trilinear couplings are allowed. There is a
potentially large trilinear lepton number breaking coupling - which is unique
to left-right models - that is proportional to the SU(2)_R gauge coupling g_R.
The couplings are parametrized by few mixing angles, making the spontaneous
R-parity breaking a natural ``unification framework'' for R-parity breaking
couplings in SUSYLR models.

</DOC>
<DOC>
<DOCNO> 84309 </DOCNO>
Boundary actions in Ponzano-Regge discretization, Quantum groups and


  Boundary actions for three-dimensional quantum gravity in the discretized
formalism of Ponzano-Regge are studied with a view towards understanding the
boundary degrees of freedom. These degrees of freedom postulated in the
holography hypothesis are supposed to be characteristic of quantum gravity
theories. In particular it is expected that some of these degrees of freedom
reside on black hole horizons. This paper is a study of these ideas in the
context of a theory of quantum gravity that requires no additional structure
such as supersymmetry or special gravitational backgrounds. Lorentzian as well
as Euclidean regimes are examined. Some surprising relationships to Liouville
theory and string theory in AdS(3) are found.

</DOC>
<DOC>
<DOCNO> 40607 </DOCNO>
Measurement of the Two-Jet Differential Cross Section in


  A measurement is presented of the two-jet differential cross section,
d^3\sigma/dE_T d\eta_1 d\eta_2, at center of mass energy sqrt{s} = 1800 GeV in
proton-antiproton collisions. The results are based on an integrated luminosity
of 86 pb^-1 collected during 1994-1995 by the CDF collaboration at the Fermilab
Tevatron collider. The differential cross section is measured as a function of
the transverse energy, E_T, of a jet in the pseudorapidity region 0.1 < |eta_1|
< 0.7 for four different pseudorapidity bins of a second jet restricted to 0.1
< |\eta_2| < 3.0. The results are compared with next-to-leading order QCD
calculations determined using the CTEQ4 and MRST sets of parton distribution
functions. None of the sets examined in this analysis provides a good
description of the data.

</DOC>
<DOC>
<DOCNO> 8576 </DOCNO>
Vibrational properties of the one-component $\sigma$ phase


  A structural model of a one-component $\sigma$-phase crystal has been
constructed by means of molecular dynamics simulation. The phonon dispersion
curves and the vibrational density of states were computed for this model. The
dependence of the vibrational properties on the thermodynamical parameters was
investigated. The vibrational density of states of the $\sigma$-phase structure
is found to be similar to that of a one-component glass with icosahedral local
order. On the basis of this comparison it is concluded that the $\sigma$ phase
can be considered to be a good crystalline reference structure for this glass.

</DOC>
<DOC>
<DOCNO> 40523 </DOCNO>
Dalitz plot analysis and branching fraction measurement of D+ and Ds+ ->


  Fermilab fixed target experiment E791 obtained a sample of $1172 \pm 61$
events of $D^+ \to \pi^- \pi^+ \pi^+$ and 848 $\pm 44$ events of $D_s^+ \to
\pi^- \pi^+ \pi^+$ decays. We find respectively $B (D^+ \to \pi^- \pi^+ \pi^+)
/ B (D^+
  \to K^- \pi^+ \pi^+) = 0.0311 \pm 0.0018 ^
  {+0.0016}_{-0.0026}$ and $B(D_s^+ \to \pi^+ \pi^- \pi^+)
  / B(D_s^+ \to \phi \pi^+) = 0.245 \pm 0.028^{+0.019}_{-0.012}$. Using a
coherent amplitude analysis to fit the Dalitz plot of the $D^+ \to \pi^- \pi^+
  \pi^+$ decay, we find strong evidence for a scalar resonance of mass
$478^{+24}_{-23}
  \pm 17 $MeV/$c^2$ and width $324^{+42}_{-40} \pm 21$
  MeV/$c^2$, compatible with what is expected for the isoscalar meson $\sigma$
>. The $D^+ \to \sigma(500)
  \pi^+$ fraction accounts for approximately half of all three-charged-pion
decays of the $D^+$ . From the Dalitz plot analysis of the $D_s^+ \to \pi^-
\pi^+ \pi^+$ decay events, we find significant contributions from the channels
$\rho^0(770)\pi^+$, $\rho^0(1450)\pi^+$,
  $f_0(980)\pi^+$, $f_2(1270)\pi^+$, and $f_0(1370)\pi^+$. We also present new
measurement of the masses and widths of the isoscalar resonances $f_0(980)$ and
$f_0(1370)$.

</DOC>
<DOC>
<DOCNO> 101014 </DOCNO>
Lagrangian torus fibration and mirror symmetry of Calabi-Yau


  In this paper we give a construction of Lagrangian torus fibration for
Calabi-Yau hypersurface in toric variety via the method of gradient flow. Using
our construction of Lagrangian torus fibration, we are able to prove the
symplectic topological version of SYZ mirror conjecture for generic Calabi-Yau
hypersurface in toric variety. We will also be able to give precise formulation
of SYZ mirror conjecture in general (including singular locus and duality of
singular fibres).

</DOC>
<DOC>
<DOCNO> 150374 </DOCNO>
Scalar Tensor Theories and Hadamard State Condition


  The Hadamard state condition is used to analyze the local constraints on the
two-point function of a quantum field conformally coupled to a background
geometry. Using these constraints we develop a scalar tensor theory which
controls the coupling of the stress-tensor induced by the two-point function of
the quantum field to the conformal class of the background metric. It is then
argued that the determination of the state-dependent part of the two-point
function is connected with the determination of a conformal frame. We comment
on a particular way to relate the theory to a specific conformal frame
(different from the background frame) in which the large scale properties are
brought into focus.

</DOC>
<DOC>
<DOCNO> 99359 </DOCNO>
Pentagon equation and matrix bialgebras


  We classify coproducts on matrix algebra in terms of solutions to some
modification of pentagon equation. The construction of Baaj and Skandalis
describing finite dimensional unitary solutions of pentagon equation is
extended to the non-unitary case. We establish the relation between Hopf-Galois
algebras and solutions to modified pentagon equation.

</DOC>
<DOC>
<DOCNO> 12824 </DOCNO>
Transport in a mesoscopic ring with a quantum dot: from the Coulomb


  The system described in this work consists of a quantum dot inserted in a
mesoscopic ring threaded by a magnetic flux. Our aim is to present a complete
description for this device and to predict the physics of a experiment with
these features.
  We have proposed a model that takes into account the conditions that are
usual in experiments with quantum dots and mesoscopic systems. In order to
solve the model, we develop a methodology to find the Green's functions of the
system by means of proper approximations.
  This system presents persistent currents as a function of a gate potential
applied to the quantum dot. We have studied the influence of both the
interaction between electrons and the hybridization between the ring and the
dot. We have found several regimes that describe different physical phenomena
involved in the system. These regimes range from the phenomenon of Coulomb
Blockade (in the high correlation limit) to a quasi non interacting regime.
Between these two limits we have found an intermediate regime where the Kondo
effect shows up.

</DOC>
<DOC>
<DOCNO> 10963 </DOCNO>
Scaling and Multi-scaling in Financial Markets


  This paper reviews some of the phenomenological models which have been
introduced to incorporate the scaling properties of financial data. It also
illustrates a microscopic model, based on heterogeneous interacting agents,
which provides a possible explanation for the complex dynamics of markets'
returns. Scaling and multi-scaling analysis performed on the simulated data is
in good quantitative agreement with the empirical results.

</DOC>
<DOC>
<DOCNO> 151318 </DOCNO>
One-loop Shift in Noncommutative Chern-Simons Coupling


  In this paper we study the one-loop shift in the coupling constant in a
noncommutative pure U(N) Chern-Simons gauge theory in three dimensions. The
one-loop shift is shown to be a constant proportional to $N$, independent of
noncommutativity parameters, and non-vanishing for U(1) theory. Possible
physical and mathematical implications of this result are discussed.

</DOC>
<DOC>
<DOCNO> 84220 </DOCNO>
Quintessence at Galactic Level?


  Recently it has been proposed that the main contributor to the dark energy of
the Universe is a dynamical, slow evolving, spatially inhomogeneous scalar
field called quintessence. We investigate the behavior of this scalar field at
galactic level by assuming that it is the dark matter compossing the halos of
galaxies. Using an exact solution of the Einstein's equations we find an
excellent concordance between our results and observations. 

</DOC>
<DOC>
<DOCNO> 170524 </DOCNO>
Local hidden-variable models and negative-probability measures


  Elaborating on a previous work by Han et al., we give a general,
basis-independent proof of the necessity of negative probability measures in
order for a class of local hidden-variable (LHV) models to violate the
Bell-CHSH inequality. Moreover, we obtain general solutions for LHV-induced
probability measures that reproduce any consistent set of probabilities.

</DOC>
<DOC>
<DOCNO> 10082 </DOCNO>
Commensurate and incommensurate correlations in Haldane gap


  We analyze the onset of incommensurabilities around the VBS point of the S=1
bilinear-biquadratic model. We propose a simple effective field theory which is
capable of reproducing all known properties of the commensurate-incommensurate
transition at the disorder point $\theta_{\rm vbs}$. Moreover, the theory
predicts another special point $\theta_{\rm disp}$, distinct from the VBS
point, where the Haldane gap behaves singularly. The ground state energy
density is an analytic function of the model parameters everywhere, thus we do
not have phase transitions in the conventional sense.

</DOC>
<DOC>
<DOCNO> 120537 </DOCNO>
ASCA view on High-Redshift Radio-Quiet Quasars


  We briefly discuss the latest ASCA results on the X-ray spectral properties
of high-redshift radio-quiet quasars.

</DOC>
<DOC>
<DOCNO> 101352 </DOCNO>
Braid presentation of virtual knots and welded knots


  The notion of a virtual knot introduced by L. Kauffman induces the notion of
a virtual braid. It is closely related with a welded braid of R. Fenn, R.
Rimanyi and C. Rourke. Alexander's and Markov's theorems for virtual knots and
braids are proved. Similar results for welded knots and braids are also proved.

</DOC>
<DOC>
<DOCNO> 122401 </DOCNO>
The Structure of the Cold Neutral ISM on 10-100 Astronomical Unit Scales


  We have used the Very Long Baseline Array (VLBA) and the Very Large Array
(VLA) to image Galactic neutral hydrogen in absorption towards four compact
extragalactic radio sources with 10 milliarcsecond resolution. Previous VLBA
data by Faison et al (1998) have shown the existence of prominent structures in
the direction of the extragalactic source 3C~138 with scale sizes of 10-20 AU
with changes in HI optical depth in excess of 0.8 $\pm$ 0.1. In this paper we
confirm the small scale \hi optical depth variations toward 3C~147 suggested
earlier at a level up to 20 % $\pm$ 5% . The sources 3C~119, 2352+495 and
0831+557 show no significant change in \hi optical depth across the sources
with one sigma limits of 30%, 50%, and 100%. Of the seven sources recently
investigated with the VLBA and VLA, only 3C~138 and 3C~147 show statistically
significant variations in HI opacities.
  Deshpande (2000) have attempted to explain the observed small-scale structure
as an extension of the observed power spectrum of structure on parsec size
scales. The predictions of Deshpande (2000) are consistent with the VLBA HI
data observed in the directions of a number of sources, including 3C~147, but
are not consistent with our previous observations of the HI opacity structure
toward 3C~138.

</DOC>
<DOC>
<DOCNO> 85003 </DOCNO>
From Gauging Nonrelativistic Translations to N-Body Dynamics


  We consider the gauging of space translations with time-dependent gauge
functions. Using fixed time gauge of relativistic theory, we consider the
gauge-invariant model describing the motion of nonrelativistic particles. When
we use gauge-invariant nonrelativistic velocities as independent variables the
translation gauge fields enter the equations through a d\times (d+1) matrix of
vielbein fields and their Abelian field strengths, which can be identified with
the torsion tensors of teleparallel formulation of relativity theory. We
consider the planar case (d=2) in some detail, with the assumption that the
action for the dreibein fields is given by the translational Chern-Simons term.
We fix the asymptotic transformations in such a way that the space part of the
metric becomes asymptotically Euclidean. The residual symmetries are (local in
time) translations and rigid rotations. We describe the effective interaction
of the d=2 N-particle problem and discuss its classical solution for N=2. The
phase space Hamiltonian H describing two-body interactions satisfies a
nonlinear equation H={\cal H}(\vec x,\vec p;H) which implies, after
quantization, a nonstandard form of the Schr\"odinger equation with energy
dependent fractional angular momentum eigenvalues. Quantum solutions of the
two-body problem are discussed. The bound states with discrete energy levels
correspond to a confined classical motion (for the planar distance between two
particles r\le r_0) and the scattering states with continuum energy correspond
to the classical motion for r>r_0. We extend our considerations by introducing
an external constant magnetic field and, for N=2, provide the classical and
quantum solutions in the confined and unconfined regimes.

</DOC>
<DOC>
<DOCNO> 120863 </DOCNO>
Infrared Helium-Hydrogen Line Ratios as a Measure of Stellar Effective


  We have observed a large sample of compact planetary nebulae in the
near-infrared to determine how the 2^1P-2^1S HeI line at 2.058um varies as a
function of stellar effective temperature, Teff. The ratio of this line with HI
Br g at 2.166um has often been used as a measure of the highest Teff present in
a stellar cluster, and hence on whether there is a cut-off in the stellar
initial mass function at high masses. However, recent photoionisation modelling
has revealed that the behaviour of this line is more complex than previously
anticipated. Our work shows that in most aspects the photoionisation models are
correct. In particular, we confirm the weakening of the 2^1P-2^1S as Teff
increases beyond 40000K. However, in many cases the model underpredicts the
observed ratio when we consider the detailed physical conditions in the
individual planetary nebulae. Furthermore, there is evidence that there is
still significant 2^1P-2^1S HeI line emission even in the planetary nebulae
with very hot (Teff>100000K) central stars. It is clear from our work that this
ratio cannot be considered as a reliable measure of effective temperature on
its own.

</DOC>
<DOC>
<DOCNO> 151873 </DOCNO>
Study of the O(N) linear sigma model at finite temperature using the


  We show that a new expansion which sums seagull and bubble graphs to all
orders, can be applied to the O(N) linear sigma model at finite temperature. We
prove that this expansion can be renormalised with the usual counterterms in a
mass independent scheme and that Goldstone's theorem is satisfied at each
order. At the one loop order of this expansion, the Hartree result for the
effective potential (daisy and superdaisy graphs) is recovered. We show that at
one loop 2PPI order, the self energy of the sigma meson can be calculated
exactly and that diagrams are summed beyond the Hartree approximation.

</DOC>
<DOC>
<DOCNO> 12690 </DOCNO>
Magnetic and electronic structures of superconducting


  The coexistence of ferromagnetism and superconductivity in
RuSr$_2$GdCu$_2$O$_8$ was reported both from experiments (by Tallon et. al.)
and first-principles calculations (by Pickett et. al.). Here we report that our
first-principles full-potential linearized augmented plane wave (FLAPW)
calculations, employing the precise crystal structure with structural
distortions (i.e., RuO$_6$ rotations) determined by neutron diffraction,
demonstrate that antiferromagnetic ordering of the Ru moments is energetically
favored over the previously proposed ferromagnetic ordering. Our results are
consistent with recently performed magnetic neutron diffraction experiments
(Lynn et. al). Ru $t_{2g}$ states, which are responsible for the magnetism,
have only a very small interaction with Cu $e_g$ states, which results in a
small exchange splitting of these states. The Fermi surface, characterized by
strongly hybridized $dp\sigma$ orbitals, has nesting features similar to those
in the two-dimensional high $T_c$ cuprate superconductors.

</DOC>
<DOC>
<DOCNO> 122442 </DOCNO>
Large-Scale Simulations of Clusters of Galaxies


  We discuss some of the computational challenges encountered in simulating the
evolution of clusters of galaxies. Eulerian adaptive mesh refinement (AMR)
techniques can successfully address these challenges but are currently being
used by only a few groups. We describe our publicly available AMR code, FLASH,
which uses an object-oriented framework to manage its AMR library, physics
modules, and automated verification. We outline the development of the FLASH
framework to include collisionless particles, permitting it to be used for
cluster simulation.

</DOC>
<DOC>
<DOCNO> 151757 </DOCNO>
On the holomorphically factorized partition function for abelian gauge


  We use holomorphic factorization to find the partition functions of an
abelian two-form chiral gauge-field on a flat six-torus. We prove that exactly
one of these partition functions is modular invariant. It turns out to be the
one that previously has been found in a hamiltonian formulation.

</DOC>
<DOC>
<DOCNO> 12378 </DOCNO>
Multifractal Measures Characterized by the Iterative Map with Two


  A one - dimensional iterative map with two control parameters, i.e. the Kim -
Kong map, is proposed. Our purpose is to investigate the characteristic
properties of this map, and to discuss numerically the multifractal behavior of
the normalized first passage time. Especially, based on the Monte Carlo
simulation, the normalized first passage time to arrive at the absorbing
barrier after starting from an arbitrary site is mainly obtained in the
presence of both absorption and reflection on a two - dimensional Sierpinski
gasket. We also discuss the multifractal spectra of the normalized first
passage time, and the numerical result of the Kim - Kong model presented will
be compared with that of the Sinai and logistic models.

</DOC>
<DOC>
<DOCNO> 120275 </DOCNO>
Weak Weak Lensing: How Accurately Can Small Shears be Measured?


  Now that weak lensing signals on the order of a percent are actively being
searched for (cosmic shear, galaxy-galaxy lensing, large radii in clusters...)
it is important to investigate how accurately weak shears can be determined.
Many systematic effects are present, and need to be understood. I show that the
Kaiser et al. technique can leave residual systematic errors at the percent
level (through imperfect PSF anisotropy correction), and present an alternative
technique which is able to recover shears a factor of ten weaker.

</DOC>
<DOC>
<DOCNO> 8645 </DOCNO>
The sound of many hands clapping


  We report on a series of measurements aimed to characterize the development
and the dynamics of the rhythmic applause in concert halls. Our results
demonstrate that while this process shares many characteristics of other
systems that are known to synchronize, it also has features that are unexpected
and unaccounted for in many other systems. In particular, we find that the
mechanism lying at the heart of the synchronization process is the period
doubling of the clapping rhythm. The characteristic interplay between
synchronized and unsynchronized regimes during the applause is the result of a
frustration in the systems. All results are understandable in the framework of
the Kuramoto model.

</DOC>
<DOC>
<DOCNO> 11767 </DOCNO>
Charge profile in vortices


  The electric charge density in the vortex lattice of superconductors is
studied within the Ginzburg-Landau theory. We show that the electrostatic
potential $\phi$ is proportional to the GL function,
$\phi\propto|\psi|^2-|\psi_\infty|^2$. Numerical results for the triangular
vortex lattice are presented.

</DOC>
<DOC>
<DOCNO> 68815 </DOCNO>
Transverse Spin in QCD: Radiative Corrections


  In this paper we address various issues connected with transverse spin in
light front QCD. The transverse spin operators, in $A^+ = 0$ gauge, expressed
in terms of the dynamical variables are explicitly interaction dependent unlike
the helicity operator which is interaction independent in the topologically
trivial sector of light-front QCD. Although it cannot be separated into an
orbital and a spin part, we have shown that there exists an interesting
decomposition of the transverse spin operator. We discuss the physical
relevance of such a decomposition. We perform a one loop renormalization of the
full transverse spin operator in light-front Hamiltonian perturbation theory
for a dressed quark state. We explicitly show that all the terms dependent on
the center of mass momenta get canceled in the matrix element. The entire
non-vanishing contribution comes from the fermion intrinsic -like part of the
transverse spin operator as a result of cancellation between the gluonic
intrinsic-like and the orbital-like part of the transverse spin operator. We
compare and contrast the calculations of transverse spin and helicity of a
dressed quark in perturbation theory.

</DOC>
<DOC>
<DOCNO> 102463 </DOCNO>
Lie algebra automorphisms in conformal field theory


  The role of automorphisms of infinite-dimensional Lie algebras in conformal
field theory is examined. Two main types of applications are discussed; they
are related to the enhancement and reduction of symmetry, respectively. The
structures one encounters also appear in other areas of physics and
mathematics. In particular, they lead to two conjectures on the sub-bundle
structure of chiral blocks, and they are instrumental in the study of
conformally invariant boundary conditions.

</DOC>
<DOC>
<DOCNO> 71157 </DOCNO>
Supersymmetry Breaking by Dimensional Reduction over Coset Spaces


  We study the dimensional reduction of a ten-dimensional supersymmetric E_8
gauge theory over six-dimensional coset spaces. We find that the coset space
dimensional reduction over a symmetric coset space leaves the four dimensional
gauge theory without any track of the original supersymmetry. On the contrary
the dimensional reduction over a non symmetric coset space leads to a softly
broken supersymmetric gauge theory in four dimensions. The SO_7/SO_6 and
G_2/SU(3) are used as representative prototypes of symmetric and non symmetric
coset spaces respectively.

</DOC>
<DOC>
<DOCNO> 178390 </DOCNO>
Solar Proton Burning Process Revisited within a Covariant Model Based on


  A covariant model based on the Bethe-Salpeter formalism is proposed for
investigating the solar proton burning process $pp\to De^+\nu_e$ and the
near-threshold deuteron disintegration via electromagnetic and weak
interactions. Results of numerical calculations of the energy dependence of
relevant cross sections and the astrophysical low-energy cross section factor
$S_{pp}$ of the proton burning process are presented. Our results confirm
previous canonical values, and the energy dependence of the $S_{pp}$ factor is
rather close to phenomenological extrapolations commonly adopted in
computations of solar nuclear reaction rates.

</DOC>
<DOC>
<DOCNO> 169563 </DOCNO>
Hidden assumptions in decoherence theory


  The role of implicit assumptions in current decoherence theory is pointed out
and clarified.

</DOC>
<DOC>
<DOCNO> 68408 </DOCNO>
Electroweak Physics, Theoretical Aspects


  I discuss two aspects of the electroweak interactions: the status of the
precision measurement of the electroweak parameters and their impact on the
Higgs search at future colliders.

</DOC>
<DOC>
<DOCNO> 170759 </DOCNO>
Geometrical Representation of Angular Momentum Coherence and Squeezing


  A simple, and elegant geometrical representation is developed to describe the
concept of coherence and squeezing for angular momentum operators. Angular
momentum squeezed states were obtained by applying Bogoliubov transformation on
the angular momentum coherent states in Schwinger representation [Phys. Rev.
{\bf{A 51}} (1995)]. We present the geometrical phase space description of
angular momentum coherent and squeezed states and relate with the harmonic
oscillator. The unique feature of our geometric representation is the
portraying of the expectation values of the angular momentum components
accompanied by their uncertainties. The bosonic representation of the angular
momentum coherent and squeezed states is compared with the conventional one
mentioning the advantages of this representation of angular momentum in context
of coherence and squeezing. Extension of our work on single mode squeezing to
double mode squeezing is presented and compared with the single mode one. We
also point out the possible applications of the geometrical representation in
analyzing the accuracy of interferometers and in studying the behavior,
dynamics of an ensemble of quantum-mechanical two-level systems and its
interaction with radiation.

</DOC>
<DOC>
<DOCNO> 178901 </DOCNO>
Shell Model Description of $^{158}$Gd


  The pseudo-SU(3) model is used to describe the low-energy spectra as well as
$E2$ and $M1$ transition strengths in $^{158}$Gd. The Hamiltonian includes
spherical single-particle energies, the quadrupole-quadrupole and proton and
neutron pairing interactions, plus four rotor-like terms. The parameters of the
Hamiltonian were fixed by systematics with the rotor-like terms determined
through a least-squares analysis. The basis states are built as linear
combinations of SU(3) states which are the direct product of SU(3) proton and
neutron states with pseudo-spin zero. The calculated results compare favorably
with the available experimental data, which demonstrates the ability of the
model to describe such nuclei.

</DOC>
<DOC>
<DOCNO> 123009 </DOCNO>
Cluster Mass Profiles from Weak Lensing II


  In Schneider, King & Erben (2000) we developed likelihood techniques to
compare the constraints on cluster mass profiles that can be obtained using the
shear and magnification information. This work considered circularly symmetric
power-law models for clusters at fairly low redshifts where the redshift
distribution of source galaxies could be neglected. Here this treatment is
extended to encompass NFW profiles which are a good description of clusters
from cosmological N-body simulations, and NFW clusters at higher redshifts
where the influence of various scenarios for the knowledge of the redshift
distribution are examined. Since in reality the overwhelming majority of
clusters have ellipsoidal rather than spherical profiles, the singular
isothermal ellipsoid (SIE) is investigated. We also briefly consider the impact
of substructure on such a likelihood analysis. In general, we find that the
shear information provides a better constraint on the NFW profile under
consideration, so this becomes the focus of what follows. The ability to
differentiate between the NFW and power-law profiles strongly depends on the
size of the data field, and on the number density of galaxies for which an
ellipticity can be measured. For higher redshift NFW profiles, there is very
little reduction (~1.5%) in the dispersion of parameter estimates when
spectroscopic redshifts, as opposed to photometric redshift estimates, are
available for the galaxies used in the lensing analysis.

</DOC>
<DOC>
<DOCNO> 101154 </DOCNO>
Symplectic maps to projective spaces and symplectic invariants


  After reviewing recent results on symplectic Lefschetz pencils and symplectic
branched covers of CP^2, we describe a new construction of maps from symplectic
manifolds of any dimension to CP^2 and the associated monodromy invariants. We
also show that a dimensional induction process makes it possible to describe
any compact symplectic manifold by a series of words in braid groups and a word
in a symmetric group.

</DOC>
<DOC>
<DOCNO> 80680 </DOCNO>
Phase Structure of Four-dimensional Simplicial Quantum Gravity with a


  The phase structure of four-dimensional simplicial quantum gravity coupled to
U(1) gauge fields has been studied using Monte-Carlo simulations. The smooth
phase is found in the intermediate region between the crumpled phase and the
branched polymer phase. This new phase has a negative string susceptibility
exponent, even if the number of vector fields (Nv) is 1. The phase transition
between the crumpled phase and the smooth phase has been studied by a finite
size scaling method. From the numerical results, we expect that this model
(coupled to one gauge field) has a higher order phase transition than first
order, which means the possibility to take the continuum limit at the critical
point. Furthermore, we consider a modification of the balls-in-boxes model for
a clear understanding of the relation between the numerical results and the
analytical one.

</DOC>
<DOC>
<DOCNO> 11986 </DOCNO>
Electronic structure of the strongly hybridized ferromagnet CeFe2


  We report on results from high-energy spectroscopic measurements on CeFe2, a
system of particular interest due to its anomalous ferromagnetism with an
unusually low Curie temperature and small magnetization compared to the other
rare earth-iron Laves phase compounds. Our experimental results indicate very
strong hybridization of the Ce 4f states with the delocalized band states,
mainly the Fe 3d states. In the interpretation and analysis of our measured
spectra, we have made use of two different theoretical approaches: The first
one is based on the Anderson impurity model, with surface contributions
explicitly taken into account. The second method consists of band-structure
calculations for bulk CeFe2. The analysis based on the Anderson impurity model
gives calculated spectra in good agreement with the whole range of measured
spectra, and reveals that the Ce 4f -- Fe 3d hybridization is considerably
reduced at the surface, resulting in even stronger hybridization in the bulk
than previously thought. The band-structure calculations are ab initio
full-potential linear muffin-tin orbital calculations within the
local-spin-density approximation of the density functional. The Ce 4f electrons
were treated as itinerant band electrons. Interestingly, the Ce 4f partial
density of states obtained from the band-structure calculations also agree well
with the experimental spectra concerning both the 4f peak position and the 4f
bandwidth, if the surface effects are properly taken into account. In addition,
results, notably the partial spin magnetic moments, from the band-structure
calculations are discussed in some detail and compared to experimental findings
and earlier calculations.

</DOC>
<DOC>
<DOCNO> 116735 </DOCNO>
The Unification of Electromagnetism and Gravitation in the Context of


  The attempts to unify electromagnetism and gravitation have included the
formulations of Herman Weyl and the Kaluza Klein theory with the fifth
dimension. More recently there have been fruitful attempts in the domain of
Quantum Superstrings and the author's formulation in terms of Quantum
Mechanical Kerr-Newman Black Holes. Though all these appear to be widely
divergent approaches, they are shown to have a unified underpinning in the
context of quantized fractal space time.

</DOC>
<DOC>
<DOCNO> 10276 </DOCNO>
Dirac, Anderson, and Goldstone on the Kagome


  We show that there exists a long-range RVB state for the kagome lattice
spin-1/2 Heisenberg antiferromagnet for which the spinons have a massless Dirac
spectrum. By considering various perturbations of the RVB state which give mass
to the fermions by breaking a symmetry, we are able to describe a wide-ranging
class of known states on the kagome lattice, including spin-Peierls solid and
chiral spin liquid states. Using an RG treatment of fluctuations about the RVB
state, we propose yet a different symmetry breaking pattern and show how
collective excitations about this state account for the gapless singlet modes
seen experimentally and numerically. We make further comparison with numerics
for Chern numbers, dimer-dimer correlation functions, the triplet gap, and
other quantities. To accomplish these calculations, we propose a variant of the
SU(N) theory which enables us to include many of the effects of Gutzwiller
projection at the mean-field level.

</DOC>
<DOC>
<DOCNO> 118360 </DOCNO>
Evidence for Pressure Driven Flows and Turbulent Dissipation in the


  We have mapped the dense gas distribution and dynamics in the NW region of
the Serpens molecular cloud in the CS(2-1) and N2H+(1-0) lines and 3 mm
continuum using the FCRAO telescope and BIMA interferometer. 7 continuum
sources are found. The N2H+ spectra are optically thin and fits to the 7
hyperfine components are used to determine the distribution of velocity
dispersion. 8 cores, 2 with continuum sources, 6 without, lie at a local
linewidth minimum and optical depth maximum. The CS spectra are optically thick
and generally self-absorbed over the full 0.2 pc extent of the map. We use the
line wings to trace outflows around at least 3, and possibly 4, of the
continuum sources, and the asymmetry in the self-absorption as a diagnostic of
relative motions between core centers and envelopes. The quiescent regions with
low N2H+ linewidth tend to have more asymmetric CS spectra than the spectra
around the continuum sources indicating higher infall speeds. These regions
have typical sizes ~5000 AU, linewidths ~0.5 km/s, and infall speeds ~0.05
km/s. The correlation of CS asymmetry with N2H+ velocity dispersion suggests
that the inward flows of material that build up pre-protostellar cores are
driven at least partly by a pressure gradient rather than by gravity alone. We
discuss a scenario for core formation and eventual star forming collapse
through the dissipation of turbulence.

</DOC>
<DOC>
<DOCNO> 100285 </DOCNO>
Abelian Varieties into 2g+1-dim.Linear Systems


  We show that polarisations of type (1,...,1,2g+2) on g-dimensional abelian
varieties are $\it{never}$ very ample, if $g\geq 3$. This disproves a
conjecture of Debarre, Hulek and Spandaw. We also give a criterion for
non-embeddings of abelian varieties into 2g+1-dimensional linear systems.

</DOC>
<DOC>
<DOCNO> 83103 </DOCNO>
Conditional indifference and conditional preservation


  The idea of preserving conditional beliefs emerged recently as a new paradigm
apt to guide the revision of epistemic states. Conditionals are substantially
different from propositional beliefs and need specific treatment. In this
paper, we present a new approach to conditionals, capturing particularly well
their dynamic part as revision policies. We thoroughly axiomatize a principle
of conditional preservation as an indifference property with respect to
conditional structures of worlds. This principle is developed in a
semi-quantitative setting, so as to reveal its fundamental meaning for belief
revision in quantitative as well as in qualitative frameworks. In fact, it is
shown to cover other proposed approaches to conditional preservation.

</DOC>
<DOC>
<DOCNO> 122487 </DOCNO>
On Dynamical Models for Radio Galaxies


  The tailed radio galaxies that have been called ``Type I'' are not a uniform
set. To study their dynamics, we have used the Ledlow-Owen data set, which
provides a new sample of 250 radio galaxies in nearby Abell clusters. These
sources divide into two clear categories based on their radio morphology. Type
A sources (``straight'') contain nearly straight jets which are embedded in
outer radio lobe. Type B sources (``tailed'') have a well-collimated jet flow
which undergoes a sudden transition, at an inner hot spot, to a less collimated
flow which continues on and forms a radio tail. We have not found any
separation of these classes in terms of radio power, radio flux size, galaxy
power or external gas density. We propose the difference is due to the
development, or not, of a disruptive flow instability, such as
Kelvin-Helmholtz, and the saturation of the instability when it develops.

</DOC>
<DOC>
<DOCNO> 13331 </DOCNO>
On the Use of Optimized Monte Carlo Methods for Studying Spin Glasses


  We start from recently published numerical data by Hatano and Gubernatis
cond-mat/0008115 to discuss properties of convergence to equilibrium of
optimized Monte Carlo methods (bivariate multi canonical and parallel
tempering). We show that these data are not thermalized, and they lead to an
erroneous physical picture. We shed some light on why the bivariate multi
canonical Monte Carlo method can fail.

</DOC>
<DOC>
<DOCNO> 102759 </DOCNO>
Tensor products of C(X)-algebras over C(X)


  Given a Hausdorff compact space X, we study the C^*-(semi)-norms on the
algebraic tensor product $A\otimes_{alg,C(X)} B$ of two C(X)-algebras A and B
over C(X). In particular, if one of the two C(X)-algebras defines a continuous
field of C^*-algebras over X, there exist minimal and maximal C^*-norms on
$A\otimes_{alg,C(X)} B$ but there does not exist any C^*-norm on
$A\otimes_{alg,C(X)} B$ in general.

</DOC>
<DOC>
<DOCNO> 102915 </DOCNO>
N=4 Supersymmetric Yang-Mills Theory on Orbifold-$T^4/{\bf Z}_2$


  We derive the partition function of N=4 supersymmetric Yang-Mills theory on
orbifold-$T^4/{\bf Z}_2$. In classical geometry, K3 surface is constructed from
the orbifold-$T^4/{\bf Z}_2$. Along the same way as the orbifold construction,
we construct the partition function of K3 surface from orbifold-$T^4/{\bf
Z}_2$. The partition function is given by the product of the contribution of
the untwisted sector of $T^4/{\bf Z}_2$, and that of the twisted sector of
$T^4/{\bf Z}_2$ i.e., ${\cal O}(-2)$ curve blow-up formula.

</DOC>
<DOC>
<DOCNO> 117083 </DOCNO>
Average observed properties of the Earth's quasi-perpendicular and


  We present a statistical analysis of 132 dayside (LT 0700-1700) bow shock
crossings of the AMPTE/IRM spacecraft. We perform a superposed epoch analysis
of plasma and magnetic field parameters as well as of low frequency magnetic
power spectra some minutes upstream and downstream of the bow shock by dividing
the events into categories depending on the angle between bow shock normal and
interplanetary magnetic field and on the plasma-beta, i.e., the ratio of plasma
to magnetic pressure.
  Downstream of the quasi-perpendicular low-beta (beta < 0.5) bow shock we find
a dominance of the left-hand polarized component at frequencies just below the
ion cyclotron frequency with amplitudes of about 3 nT. These waves are
identified as ion cyclotron waves which grow in a low-beta regime due to the
proton temperature anisotropy. We find a strong correlation of this anisotropy
with the intensity of the left-hand polarized component. Downstream of some
nearly perpendicular high-beta (beta > 1.0) crossings mirror waves are
identified. However, there are also cases where the conditions for mirror modes
are met downstream of the nearly perpendicular shock, but no mirror waves are
observed.

</DOC>
<DOC>
<DOCNO> 151419 </DOCNO>
Integrability of the $C_{n}$ and $BC_{n}$ Ruijsenaars-Schneider models


  We study the $C_{n}$ and $BC_{n}$ Ruijsenaars-Schneider(RS) models with
interaction potential of trigonometric and rational types. The Lax pairs for
these models are constructed and the involutive Hamiltonians are also given.
Taking nonrelativistic limit, we also obtain the Lax pairs for the
corresponding Calogero-Moser systems.

</DOC>
<DOC>
<DOCNO> 80920 </DOCNO>
Exact Chiral Symmetry for Domain Wall Fermions with Finite L_s


  We show how the standard domain wall action can be simply modified to allow
arbitrarily exact chiral symmetry at finite fifth dimensional extent $L_s$. We
note that the method can be used for both quenched and dynamical calculations.
We test the method using smooth and thermalized gauge field configurations. We
also make comparisons of the performance (cost) of the domain wall operator for
spectroscopy compared to other methods such as the overlap-Dirac operator and
find both methods are comparable in cost.

</DOC>
<DOC>
<DOCNO> 170154 </DOCNO>
Comment on ``Dispersion-Independent High-Visibility Quantum Interference


  We show in this Comment that the interpretation of experimental data as well
as the theory presented in Atat\"ure et al. [Phys. Rev. Lett. 84, 618 (2000)]
are incorrect and discuss why such a scheme cannot be used to "recover"
high-visibility quantum interference.

</DOC>
<DOC>
<DOCNO> 100625 </DOCNO>
On representations of a q-analogue of the *-algebra Pol(Mat_{2,2})


  Bounded Hilbert space *-representations are studied for a q-analogue of the
*-algebra Pol(Mat_{2,2}) of polynomials on the space Mat_{2,2} of complex
2\times 2 matrices.

</DOC>
<DOC>
<DOCNO> 13148 </DOCNO>
A study of the tunnelling-charging Hamiltonian of a Cooper pair pump


  General properties of the tunnelling-charging Hamiltonian of a Cooper pair
pump are examined with emphasis on the symmetries of the model. An efficient
block-diagonalisation scheme and a compatible Fourier expansion of the
eigenstates is constructed and applied in order to gather information on
important observables. Systematics of the adiabatic pumping with respect to all
of the model parameters are obtained and the link to the geometrical Berry's
phase is identified.

</DOC>
<DOC>
<DOCNO> 122721 </DOCNO>
Stereo Imaging of the VHE Gamma-Rays with HEGRA and H.E.S.S


  At present, the ground-based astronomy of very high energy (VHE) (E>100 GeV)
gamma-rays experiences the challenging transition phase caused by the
substantial upgrading of its observational instrumentation. Recently the HEGRA
collaboration has evidently demonstrated the power of arrays of imaging
atmospheric Cherenkov telescopes and initiated a number of complementary
projects, such as H.E.S.S., CANGAROO IV, VERITAS. The common philosophy of
those projects is based on the stereoscopic observations of air showers with a
number of imaging telescopes simultaneously. Such observations allow to reduce
substantially the effective energy threshold of detected gamma-ray showers; to
improve the angular and energy resolution for individual gamma-rays; to gain in
suppression of the cosmic ray background. In my talk I have summarized the
general advantages and achieved sensitivity of the stereoscopic observations
using the HEGRA data taken with an array of 5 imaging telescopes having the
energy threshold of 500 GeV. These results completed with the relevant
simulations may be extrapolated on a firm ground towards the future H.E.S.S.
(phase I) array of four 12 m imaging telescopes with the estimated energy
threshold below 100 GeV. Here I discuss in short the anticipated performance of
such an array.

</DOC>
<DOC>
<DOCNO> 67713 </DOCNO>
Separating Different Models from Measuring $\alpha, \beta, \gamma$


  New physics effects on the $B^0-\bar{B}^0$ mixing and B-decay amplitudes are
discussed. By a combined analysis, the model of new physics can be partially
distinguished.It is emphasized that the extraction of unitarity angles $\beta$
and $\gamma$ through rare decay $K\to \pi\nu\tilde{\nu}$ and charged B decay
$B^{\pm}\to DK^{\pm}$ respectively is not likely to be affected by new physics.
Such an observation could be used to distinguish the new physics effects from
different mode ls. For instance, the top quark two-Higgs doublet model can be
easily separated from those models without new phase in B-decay amplitudes, and
can be further distinguished from the most general two Higgs doublet model by
its absence of new phase in the $B^0-\bar{B}^0$ mixing.

</DOC>
<DOC>
<DOCNO> 117041 </DOCNO>
Cell Microtubules as Cavities: Quantum Coherence and Energy Transfer?


  A model is presented for dissipationless energy transfer in cell microtubules
due to quantum coherent states. The model is based on conjectured (hydrated)
ferroelectric properties of microtubular arrangements. Ferroelectricity is
essential in providing the necessary isolation against thermal losses in thin
interior regions, full of ordered water, near the tubulin dimer walls of the
microtubule. These play the role of cavity regions, which are similar to
electromagnetic cavities of quantum optics. As a result, the formation of
(macroscopic) quantum coherent states of electric dipoles on the tubulin dimers
may occur. Some experiments, inspired by quantum optics, are suggested for the
falsification of this scenario.

</DOC>
<DOC>
<DOCNO> 13443 </DOCNO>
Effective Chern-Simons Theories of Pfaffian and Parafermionic Quantum


  We present a pure Chern-Simons formulation of families of interesting
Conformal Field Theories describing edge states of non-Abelian Quantum Hall
states. These theories contain two Abelian Chern-Simons fields describing the
electromagnetically charged and neutral sectors of these models, respectively.
The charged sector is the usual Abelian Chern-Simons theory that successfully
describes Laughlin-type incompressible fluids. The neutral sector is a
2+1-dimensional theory analogous to the 1+1-dimensional orbifold conformal
field theories. It is based on the gauge group O(2) which contains a ${\bf
Z}_2$ disconnected group manifold, which is the salient feature of this theory.
At level q, the Abelian theory of the neutral sector gives rise to a ${\bf
Z}_{2q}$ symmetry, which is further reduced by imposing the ${\bf Z}_2$
symmetry of charge-conjugation invariance. The remaining ${\bf Z}_q$ symmetry
of the neutral sector is the origin of the non-Abelian statistics of the
(fermionic) q-Pfaffian states.

</DOC>
<DOC>
<DOCNO> 71505 </DOCNO>
Light-Front-Quantized QCD in Light-Cone Gauge: The Doubly Transverse


  The light-front (LF) quantization of QCD in light-cone gauge has a number of
remarkable advantages, including explicit unitarity, a physical Fock expansion,
the absence of ghost degrees of freedom, and the decoupling properties needed
to prove factorization theorems in high momentum transfer inclusive and
exclusive reactions. We present a systematic study of LF-quantized gauge theory
following the Dirac method and construct the Dyson-Wick S-matrix expansion
based on LF-time-ordered products. The free theory gauge field is shown to
satisfy the Lorentz condition as an operator equation as well as the light-cone
gauge condition. Its propagator is found to be transverse with respect to both
its four-momentum and the gauge direction. The interaction Hamiltonian of QCD
can be expressed in a form resembling that of covariant theory, except for
additional instantaneous interactions which can be treated systematically. The
renormalization constants in YM theory are shown to satisfy the identity
$Z_1=Z_3$ at one loop order. The QCD $\beta$ function computed in the
noncovariant light-cone gauge agrees with that known in the conventional
framework. Some comments on the relationship of our LF framework, with the
doubly transverse gauge propagator, to the analytic effective charge and
renormalization scheme defined by the pinch technique, the unitarity relations
and the spectral representation are also made. LF quantization thus provides a
consistent formulation of gauge theory, despite the fact that the hyperplanes
$x^{\pm}=0$ used to impose boundary conditions constitute characteristic
surfaces of a hyperbolic partial differential equation.

</DOC>
<DOC>
<DOCNO> 151772 </DOCNO>
Discrete Torsion in Perturbative Heterotic String Theory


  In this paper we analyze discrete torsion in perturbative heterotic string
theory. In previous work we have given a purely mathematical explanation of
discrete torsion as the choice of orbifold group action on a B field, in the
case that d H = 0; in this paper, we perform the analogous calculations in
heterotic strings where d H is nonzero.

</DOC>
<DOC>
<DOCNO> 117010 </DOCNO>
P-Loop Oscillator on Clifford Manifolds and Black Hole Entropy


  A new relativity theory, or more concretely an extended relativity theory,
actively developed by one of the authors incorporated 3 basic concepts. They
are the old idea of Chew about bootstrapping, Nottale's scale relativity, and
enlargement of the conventional time-space by inclusion of noncommutative
Clifford manifolds where all p-branes are treated on equal footing. The latter
allowed one to write a master action functional. The resulting functional
equation is simplified and applied to the p-loop oscillator. Its respective
solution is a generalization of the conventional point oscillator. In addition
, it exhibits some novel features: an emergence of two explicit scales
delineating the asymptotic regimes (Planck scale region and a smooth region of
a conventional point oscillator). In the most interesting Planck scale regime,
the solution reproduces in an elementary fashion the basic relations of string
theory (including string tension quantization). In addition, it is shown that
comparing the massive (super) string degeneracy with the p-loop degeneracy one
is arriving at the proportionality between the Shannon entropy of a p-loop
oscillator in D-dimensional space and the Bekenstein-Hawking entropy of the
black hole of a size comparable with a string scale.

</DOC>
<DOC>
<DOCNO> 80652 </DOCNO>
Massive chiral random matrix ensembles at beta = 1 & 4 : QCD Dirac


  The zero momentum sectors in effective theories of QCD coupled to pseudoreal
(two colors) and real (adjoint) quarks have alternative descriptions in terms
of chiral orthogonal and symplectic ensembles of random matrices. Using this
correspondence, we compute correlation functions of Dirac operator eigenvalues
within a sector with an arbitrary topological charge in a presence of finite
quark masses of the order of the smallest Dirac eigenvalue. These novel
correlation functions, expressed in terms of Pfaffians, interpolate between
known results for the chiral and quenched limits as quark masses vary.

</DOC>
<DOC>
<DOCNO> 100680 </DOCNO>
The harmonic product of $\delta (x_{1},..., x_{n})$ and $\delta (x_{1})$


  In the framework of nonstandard analysis, Bang-He Li and the author defined
the product of any two distributions on $R^n$ via their harmonic
representations. The product of $\delta (x_{1},..., x_{n})$ and $\delta
(x_{1})$ was calculated by Kuribayashi and the author in [LK]. In this paper,
the result of [LK] is improved to $$\delta (x_{1},..., x_{n})\circ \delta
(x_{1}) =\dfrac{1}{2\pi\rho} \delta (x_{1},..., x_{n}) {mod} {infinitesimals}$$
where $\rho$ is a positive infinitesimal. Moreover two combinatorial identities
are obtained as byproducts.

</DOC>
<DOC>
<DOCNO> 9949 </DOCNO>
Universal behavior of relaxational heterogeneity in glasses and liquids


  We report an investigation of the heterogeneity in super-cooled liquids and
glasses using the non-Gaussianity parameter. We simulate selenium and a binary
Lennard-Jones system by molecular dynamics. In the non-Gaussianity three time
domains can be distinguished. First there is an increase on the ps-scale due to
the vibrational (ballistic) motion of the atoms. This is followed, on an
intermediate time-scale, by a growth, due to local relaxations
(beta-relaxation) at not too high temperatures. A maximum is reached at times
corresponding to long range diffusion (alpha-relaxation). At long times the
non-Gaussianity slowly drops, the system becoming homogeneous on these
time-scales. In both systems studied, the non-Gaussianity follows in the
intermediate time domain, corresponding to the beta-relaxations, a law ~ t^1/2.
This general behavior is explained by collective hopping and dynamic
heterogeneity. We support this finding by a model calculation.

</DOC>
<DOC>
<DOCNO> 118397 </DOCNO>
Bimodal production of Be and B in the early Galaxy


  Recently models based on the acceleration of metal-rich material inside
superbubbles have been proposed to account for the observed abundances of Be
and B in metal-poor halo stars. We analyse some of the implications of these
models for the distribution of the Be/O and B/O abundance ratios. In
particular, we discuss the possible scatter in the data and argue that LiBeB
production in the very early Galaxy was probably bimodal, with isolated
supernovae giving rise to a low-efficiency mechanism, and collective supernovae
exploding in an OB association inducing a high-efficiency mechanism. This
should produce two populations of halo stars, one with high L/M ratios (light
elements/metals), and the other with L/M ratios about ten times lower. The
relative weight of these two populations depends on the fraction of supernovae
exploding inside superbubbles. In this context, we discuss the recent
observation of the B-depleted, Li-normal star HD 160617 (Primas, et al., 1998),
as well as the reported spread in the Be data at [Fe/H] ~ -2.2 (Boesgaard, et
al., 1999). Finally, we predict that Be will be found to be even more deficient
than B in HD 160617.

</DOC>
<DOC>
<DOCNO> 100766 </DOCNO>
Number Operator Algebras and deformations of epsilon-algebras


  It is well known that the Lie-algebra structure on quantum algebras gives
rise to a Poisson-algebra structure on classical algebras as the Planck
constant goes to 0. We show that this correspondance still holds in the
generalization of super- algebra introduced by Scheunert, called
epsilon-algebra. We illustrate this with the example of Number Operator
Algebras, a new kind of object that we have defined and classified under some
assumptions.

</DOC>
<DOC>
<DOCNO> 151770 </DOCNO>
Chern-Simons Supersymmetric Branes


  In this paper we continue the study of the model proposed in the previous
paper hep-th/0002077. The model consist of a system of extended objects of
diverse dimensionalities, with or without boundaries, with actions of the
Chern-Simons form for a supergroup. We also discuss possible connections with
Superstring/M-theory.

</DOC>
<DOC>
<DOCNO> 122252 </DOCNO>
Gravitational Microlensing of Gamma-Ray Burst Afterglows by Single and


  We calculate the magnification light curves due to stellar microlensing of
gamma-ray burst (GRB) afterglows. A GRB source appears on the sky as a thin
ring which expands faster than the speed of light and is maximally magnified as
it crosses the lens caustics. While a single star lens produces a single peak
in the magnification light curve, binary star lenses may produce multiple
peaks. The shape of the magnification light curve provides invaluable
information on the surface brightness distribution of the afterglow photosphere
on sub micro-arcsecond scales. We find that all afterglows are likely to show
variability at the level of a few percent about a year following the explosion,
due to stars which are separated by tens of Einstein radii from their
line-of-sight.

</DOC>
<DOC>
<DOCNO> 10491 </DOCNO>
Spin-Peierls Dimerization of a s=1/2 Heisenberg Antiferromagnet on a


  Dimerization of a spin-half Heisenberg antiferromagnet on a square lattice is
investigated for several possible dimerized configurations, some of which are
shown to have lower ground state energies than the others. In particular, the
lattice deformations resulting in alternate stronger and weaker couplings along
both the principal axes of a square lattice are shown to result in a larger
gain in magnetic energy. In addition, a `columnar' configuration is shown to
have a lower ground state energy and a faster increase in the energy gap
parameter than a `staggered' configuration. The inclusion of unexpanded
exchange coupling leads to a power law behaviour for the magnetic energy gain
and energy gap, which is qualitatively different from that reported earlier.
Instead of increasing as $\delta ^{x}$, the two quantities depend on $\delta $
as $\delta ^{\nu}/| \ln \delta | .$ This is true both in the near critical
regime $(0\leq \delta \leq 0.1)$ as well as in the far regime $(0\leq \delta
<1)$. It is suggested that the unexpanded exchange coupling is as much a source
of the logarithmic dependence as a correction due to the contribution of
umklapp processes. Staggered magnetization is shown to follow the same $\delta
$-dependence in all the configurations in the small $\delta $-regime, while for
$0\leq \delta <1$, it follows the power law $\delta ^{x}$.

</DOC>
<DOC>
<DOCNO> 40195 </DOCNO>
Measurement of inclusive production of charmonium states in B meson


  We reconstruct the charmonium mesons J/psi, psi(2S) and chi_C1 using a sample
of 8.46 x 10^6 B-anti-B events collected by the BABAR detector operating at
e^+e^- center of mass energies near the Y(4S) resonance. By measuring rates
relative to the branching fraction of the J/psi, we obtain preliminary
inclusive B branching fractions of (0.25+/-0.02+/-0.02)% to the psi(2S) and
(0.39+/-0.04+/-0.04)% to the chi_C1, and set a 90% confidence level limit of
0.24% on decays through the chi_C2.

</DOC>
<DOC>
<DOCNO> 13521 </DOCNO>
Band-by-band decomposition of the Born effective charges


  The Born effective charge, Z*, that describes the polarization created by
collective atomic displacements, can be computed from first-principles
following different techniques. We establish the connections existing between
these different formulations, and analyze the related band-by-band
decompositions. We show that unlike for the full Z*, the different band-by-band
values are not equal, and emphasize that one of them has a natural physical
meaning in terms of Wannier functions.

</DOC>
<DOC>
<DOCNO> 68418 </DOCNO>
QED correction to radiative tail from elastic peak in DIS


  We calculate DIS cross section under kinematical requirements when a final
hadron state is a single proton. The process in the lowest order is known as
radiative tail from elastic peak. We take into account correction, coming from
emission of virtual and soft real photons, to the amplitude of this process as
well as the one, induced by emission of additional hard photon and a hard pair.
Resulting contributions of these channels are presented in the leading and,
partly, next-to-leading logarithmic approximations. Some general expressions
for the photon contributions are given. Numerical results are presented for
kinematical conditions of the current experiments on DIS.

</DOC>
<DOC>
<DOCNO> 9347 </DOCNO>
Lattice dynamics effects on small polaron properties


  This study details the conditions under which strong-coupling perturbation
theory can be applied to the molecular crystal model, a fundamental theoretical
tool for analysis of the polaron properties. I show that lattice dimensionality
and intermolecular forces play a key role in imposing constraints on the
applicability of the perturbative approach. The polaron effective mass has been
computed in different regimes ranging from the fully antiadiabatic to the fully
adiabatic. The polaron masses become essentially dimension independent for
sufficiently strong intermolecular coupling strengths and converge to much
lower values than those tradition-ally obtained in small-polaron theory. I find
evidence for a self-trapping transition in a moderately adiabatic regime at an
electron-phonon coupling value of .3. Our results point to a substantial
independence of the self-trapping event on dimensionality.

</DOC>
<DOC>
<DOCNO> 117953 </DOCNO>
Star Formation and Chemical Evolution of Lyman-Break Galaxies


  The number density and clustering properties of Lyman-break galaxies (LBGs)
observed at redshift $z\sim 3$ are best explained by assuming that they are
associated with the most massive haloes at $z\sim 3$ predicted in hierarchical
models of structure formation. In this paper we study, under the same
assumption, how star formation and chemical enrichment may have proceeded in
the LBG population. A consistent model, in which the amount of cold gas
available for star formation must be regulated, is suggested. It is found that
gas cooling in dark haloes provides a natural regulation process. In this
model, the star formation rate in an LBG host halo is roughly constant over
about 1 Gyr. The predicted star formation rates and effective radii are
consistent with observations. The metallicity of the gas associated with an LBG
is roughly equal to the chemical yield, or about the order of $1 Z_{\odot}$ for
a Salpeter IMF. The contribution to the total metals of LBGs is roughly
consistent with that obtained from the observed cosmic star formation history.
The model predicts a marked radial metallicity gradient in a galaxy, with the
gas in the outer region having much lower metallicity. As a result, the
metallicities for the damped Lyman-alpha absorption systems expected from the
LBG population are low. Since LBG halos are filled with hot gas in this model,
their contributions to the soft X-ray background and to the UV ionization
background are calculated and discussed.

</DOC>
<DOC>
<DOCNO> 174503 </DOCNO>
Thermal hard-photons probing multifragmentation in nuclear collisions


  Hard-photon (E$_{\gamma} >$ 30 MeV) emission issuing from proton-neutron
bremsstrahlung collisions is investigated in four different heavy-ion reactions
at intermediate bombarding energies ($^{36}$Ar+$^{197}$Au, $^{107}$Ag,
$^{58}$Ni, $^{12}$C at 60{\it A} MeV) coupling the TAPS photon spectrometer
with two charged-particle multidetectors covering more than 80% of the solid
angle. The hard-photon spectra of the three heavier targets result from the
combination of two distinct exponential distributions with different slope
parameters, a result which deviates from the behaviour expected for hard-photon
production just in first-chance proton-neutron collisions. The thermal origin
of the steeper bremsstrahlung component is confirmed by the characteristics of
its slope and angular distribution. Such thermal hard-photons convey
undisturbed information of the thermodynamical state of hot and excited nuclear
systems undergoing multifragmentation.

</DOC>
<DOC>
<DOCNO> 120888 </DOCNO>
All-sky convolution for polarimetry experiments


  We discuss all-sky convolution of the instrument beam with the sky signal in
polarimetry experiments, such as the Planck mission which will map the
temperature anisotropy and polarization of the cosmic microwave background
(CMB). To account properly for stray light (from e.g. the galaxy, sun, and
planets) in the far side-lobes of such an experiment, it is necessary to
perform the beam convolution over the full sky. We discuss this process in
multipole space for an arbitrary beam response, fully including the effects of
beam asymmetry and cross-polarization. The form of the convolution in multipole
space is such that the Wandelt-Gorski fast technique for all-sky convolution of
scalar signals (e.g. temperature) can be applied with little modification. We
further show that for the special case of a pure co-polarized, axisymmetric
beam the effect of the convolution can be described by spin-weighted window
functions. In the limits of a small angle beam and large Legendre multipoles,
the spin-weight 2 window function for the linear polarization reduces to the
usual scalar window function used in previous analyses of beam effects in CMB
polarimetry experiments. While we focus on the example of polarimetry
experiments in the context of CMB studies, we emphasise that the formalism we
develop is applicable to anisotropic filtering of arbitrary tensor fields on
the sphere.

</DOC>
<DOC>
<DOCNO> 123078 </DOCNO>
In-flight main beam reconstruction for Planck-LFI


  In-flight measurement of the antenna main beams of the Planck instruments is
a crucial input to the data analysis pipeline. We study the main beam
reconstruction achievable through external planets using a flight simulator to
model their observation. We restrict our analysis to the 30 GHz LFI channel but
the method can be easily extended to higher frequency channels. We show that it
is possible to fit the antenna response from Jupiter and Saturn to obtain an
accurate, robust, simple and fast reconstruction of the main beam properties
under very general conditions, independently of the calibration accuracy.
  In addition, we find that a bivariate Gaussian approximation of the main beam
shapes represents a significant improvement with respect to a symmetric
representation.
  We also show that it is possible to combine the detection of the planet's
transit and Planck's very accurate in-flight calibration to measure the
planet's temperature at millimetric wavelengths with an accuracy at the %
level.
  This work is based on Planck-LFI activities.

</DOC>
<DOC>
<DOCNO> 71933 </DOCNO>
On the parametrization of atmospheric muon angular flux underwater


  The analytical expression for angular integral flux of atmospheric muons in
matter with the explicit relation of its parameters with those of the sea level
spectrum is obtained. The fitting formula for the sea level muon spectrum at
different zenith angles for spherical atmosphere is proposed. The concrete
calculations for pure water are presented. Fluctuations of muon energy losses
are taken into account by means of parametrized correction factor calculated
using survival probabilities resulted from Monte Carlo simulations.
Parametrizations of all continuous energy losses are obtained with using the
most recent expressions for muon interaction cross-sections. The corresponding
parametrization errors and field of method application are comprehensively
discussed. The proposed formulae could be useful primarily for experimentalists
processing data of arrays located deep under water or under ice.

</DOC>
<DOC>
<DOCNO> 8708 </DOCNO>
Metallic and insulating behaviour of the two-dimensional electron gas on


  The resistance R of the 2DEG on the vicinal Si surface shows an unusual
behaviour, which is very different from that in the (100) Si MOSFET where an
unconventional metal to insulator transition has been reported. The crossover
from the insulator with dR/dT<0 to the metal with dR/dT>0 occurs at a low
resistance of R_{\Box}^c \sim 0.04h/e^2. At the low-temperature transition,
which we attribute to the existence of a narrow impurity band at the interface,
a distinct hysteresis in the resistance is detected. At higher temperatures,
another change in the sign of dR/dT is seen and related to the crossover from
the degenerate to non-degenerate 2DEG.

</DOC>
<DOC>
<DOCNO> 99587 </DOCNO>
Geometric formulas for Smale invariants of codimension two immersions


  We give three formulas expressing the Smale invariant of an immersion f of a
(4k-1)-sphere into (4k+1)-space. The terms of the formulas are geometric
characteristics of any generic smooth map g of any oriented 4k-dimensional
manifold, where g restricted to the boundary is an immersion regularly
homotopic to f in (6k-1)-space.
  The formulas imply that if f and g are two non-regularly homotopic immersions
of a (4k-1)-sphere into (4k+1)-space then they are also non-regularly homotopic
as immersions into (6k-1)-space. Moreover, any generic homotopy in (6k-1)-space
connecting f to g must have at least a_k(2k-1)! cusps, where a_k=2 if k is odd
and a_k=1 if k is even.

</DOC>
<DOC>
<DOCNO> 67712 </DOCNO>
Generalized Mesons in Dense QCD


  QCD superconductors in the color-flavor-locked (CFL) phase support
excitations (generalized mesons) that can be described as pairs of particles or
holes (rather than particle-hole) around a gapped Fermi surface. In weak
coupling and to leading logarithm accuracy the scalar and pseudoscalar
excitations are massless and the vector and axial-vector excitations are
massive and degenerate. The massless scalar excitations are combined with the
longitudinal gluons leading to the Meissner effect in the CFL phase. The mass
of the composite vector excitations is close to twice the gap in weak coupling,
but goes asymptotically to zero with increasing coupling thereby realizing
Georgi's vector limit in cold and dense matter. We discuss the possible mixing
of the composite scalar and vector excitations with the gluons, their possible
coupling to the modified photons and their decay into light pseudoscalars in
the CFL phase. The issue of hidden gauge-symmetry in the QCD superconductor is
critically examined. The physical implications of our results on soft dilepton
and neutrino emission in cold and dense matter are briefly discussed.

</DOC>
<DOC>
<DOCNO> 101655 </DOCNO>
A new proof of the Frobenius conjecture on the dimensions of real


  A new simple way to prove the Frobenius conjecture on the dimensions of real
algebras without zero divisors is given.

</DOC>
<DOC>
<DOCNO> 71077 </DOCNO>
No-go for exactly degenerate neutrinos at high scale?


  We show in a model independent manner that, if the magnitudes of Majorana
masses of neutrinos are exactly equal at some high scale, the radiative
corrections cannot reproduce the observed masses and mixing spectrum at the low
scale, irrespective of the Majorana phases or the mixing angles at the high
scale.

</DOC>
<DOC>
<DOCNO> 83487 </DOCNO>
Index Assignment for Multichannel Communication under Failure


  We consider the problem of multiple description scalar quantizers and
describing the achievable rate-distortion tuples in that setting. We formulate
it as a combinatorial optimization problem of arranging numbers in a matrix to
minimize the maximum difference between the largest and the smallest number in
any row or column. We develop a technique for deriving lower bounds on the
distortion at given channel rates. The approach is constructive, thus allowing
an algorithm that gives a closely matching upper bound. For the case of two
communication channels with equal rates, the bounds coincide, thus giving the
precise lowest achievable distortion at fixed rates. The bounds are within a
small constant for higher number of channels. To the best of our knowledge,
this is the first result concerning systems with more than two communication
channels. The problem is also equivalent to the bandwidth minimization problem
of Hamming graphs.

</DOC>
<DOC>
<DOCNO> 13804 </DOCNO>
Out-of-Equilibrium Kondo Effect: Response to Pulsed Fields


  The current in response to a rectangular pulsed bias potential is calculated
exactly for a special point in the parameter space of the nonequilibrium Kondo
model. Our simple analytical solution shows the all essential features
predicted by the noncrossing approximation, including a hierarchy of time
scales for the rise, saturation, and fall-off of the current; current
oscillations with a frequency of eV/hbar; and the instantaneous reversal of the
fall-off current for certain pulse lengths. Rich interference patterns are
found for a nonzero magnetic field (either dc or pulsed), with several
underlying time scales. These features should be observable in ultra small
quantum dots.

</DOC>
<DOC>
<DOCNO> 39800 </DOCNO>
Seeking Gauge Bileptons in Linear Colliders


  A promising direction to find physics beyond the standard model is to look
for violation of $L_{e,\mu,\tau}$ conservation. In particular the process $e^-
e^- \to \mu^- \mu^-$ with the exchange of a gauge bilepton has a striking
signal without background and is predicted in the most economical model to have
a cross-section an order of magnitude higher than previous estimates.

</DOC>
<DOC>
<DOCNO> 121637 </DOCNO>
A Moderate Cluster Cooling Flow Model


  We propose that the outer portions of cooling flows (CFs) in clusters of
galaxies are frequently disrupted by radio jets, and that their effective ages
are much shorter than the cluster ages. The inner regions, where the gas
density is higher, are more difficult to disrupt, and may continue to harbor
CFs even after disruption events. The main assumption of the proposed scenario
is that, on a time scale of about 2-4 times 10^9 years the cD galaxies in CF
clusters undergo powerful bursts of AGN activity that produce strong radio
jets. The jets excite shock waves moving at several thousands km/sec and heat
the CF region, hence terminating it in the outer regions. The total accreted
mass due to the CF is an order of magnitude lower than the mass accreted
according to the "standard" CF model (which assumes an undisturbed CF for a
time equal to the age of the cluster). The scenario, therefore, brings to
agreement the observations that a large fraction of clusters harbor CFs, that
strong optical and radio activity are present only in the very inner regions of
CFs, and the lack of a satisfactory reservoir of the expected (in the standard
CF model) large mass that has been cooling over the life of the cluster.

</DOC>
<DOC>
<DOCNO> 9498 </DOCNO>
Many-polaron system confined to a quantum dot: ground-state energy and


  We find for the first time the ground state energy and the optical absorption
spectra for N electrons (holes) interacting with each other and with the
longitudinal optical (LO) phonons at an arbitrary electron-phonon coupling
strength $\alpha$ in a parabolic confinement potential. A recently developed
path integral formalism for identical particles is used in order to account for
the fermion statistics. The approach is applicable to closed and open shells.
Using an extension of the Jensen-Feynman variational principle, the ground
state energy of the N-polarons system in a parabolic confinement potential is
analyzed as a function of N and $\alpha$. A ferromagnetic-to-nonmagnetic
transition is shown to occur between states with different total spin of the
system in the case of strong electron-phonon interaction. This transition is
manifested through the optical absorption spectra and should be experimentally
observable. Strong mixing between zero-phonon and one-phonon states is revealed
in the optical absorption spectrum, when the confinement frequency parameter is
in resonance with the LO phonon frequency ("confinement-phonon resonance").
Moments of the optical absorption spectra are calculated for a N-polaron system
in a parabolic quantum dot.

</DOC>
<DOC>
<DOCNO> 170484 </DOCNO>
Quantum Teleportation with a Complete Bell State Measurement


  We report a quantum teleportation experiment in which nonlinear interactions
are used for the Bell state measurements. The experimental results demonstrate
the working principle of irreversibly teleporting an unknown arbitrary quantum
state from one system to another distant system by disassembling into and then
later reconstructing from purely classical information and nonclassical EPR
correlations. The distinct feature of this experiment is that \emph{all} four
Bell states can be distinguished in the Bell state measurement. Teleportation
of a quantum state can thus occur with certainty in principle.

</DOC>
<DOC>
<DOCNO> 39751 </DOCNO>
Charged Pion Energy Reconstruction in the ATLAS Barrel Calorimeter


  The intrinsic performance of the ATLAS barrel and extended barrel
calorimeters for the measurement of charged pions is presented. Pion energy
scans (E = 20, 50, 200, 400 and 1000 GeV) at two pseudo-rapidity points ($\eta$
= 0.3 and 1.3) and pseudorapidity scans ($-0.2 < \eta < 1.8$) with pions of
constant transverse energy ($E_T = 20$ and 50 GeV) are analysed. A simple
approach, that accounts in first order for non-compensation and dead material
effects, is used for the pion energy reconstruction. The intrinsic performances
of the calorimeter are studied: resolution, linearity, effect of dead material,
tails in the energy distribution. The effect of electronic noise, cell energy
cuts and restricted cone size are investigated.

</DOC>
<DOC>
<DOCNO> 119279 </DOCNO>
Numerical Simulations in Cosmology II: Spatial and Velocity Biases


  We give a summary of recent results on spatial and velocity biases in
cosmological models. Progress in numerical techniques made it possible to
simulate halos in large volumes with a such accuracy that halos survive in
dense environments of groups and clusters of galaxies. Halos in simulations
look like real galaxies, and, thus, can be used to study the biases --
differences between galaxies and the dark matter. The biases depend on scale,
redshift, and circular velocities of selected halos. Two processes seem to
define the evolution of the spatial bias: (1) statistical bias and (2) merger
bias (merging of galaxies, which happens preferentially in groups, reduces the
number of galaxies, but does not affect the clustering of the dark matter).
There are two kinds of velocity bias. The pair-wise velocity bias is
b_12=0.6-0.8 at r< 5Mpc/h, z=0. This bias mostly reflects the spatial bias and
provides almost no information on the relative velocities of the galaxies and
the dark matter. One-point velocity bias is a better measure of the velocities.
Inside clusters the galaxies should move slightly faster (b_v =1.1-1.3) than
the dark matter. Qualitatively this result can be understood using the Jeans
equations of the stellar dynamics. For the standard LCDM model we find that the
correlation function and the power spectrum of galaxy-size halos at z=0 are
antibiased on scales r<5Mpc/h and k=(0.15-30)h/Mpc.

</DOC>
<DOC>
<DOCNO> 100290 </DOCNO>
Extrapolation Methods for Improving the Convergence of Oligomer


  Quasi-onedimensional stereoregular polymers as for example polyacetylene are
currently of considerable interest. There are basically two different
approaches for doing electronic structure calculations: One method is
essentially based on concepts of solid state theory. The other method is
essentially a quantum chemical method since it approximates the polymer by
oligomers consisting of a finite number of monomer units. In this way, the
highly developed technology of quantum chemical molecular programs can be used.
Unfortunately, oligomers of finite size are not necessarily able to model those
features of a polymer which crucially depend of its in principle infinite
extension. In such a case extrapolation techniques can be extremely helpful.
For example, one can perform electronic structure calculations for a sequence
of oligomers with an increasing number of monomer units. In the next step, one
then can try to determine the limit of this sequence for an oligomer of
infinite length with the help of suitable extrapolation methods. Several
different extrapolation methods are discussed which are able to accomplish an
extrapolation of energies and properties of oligomers to the infinite chain
limit. Calculations for the ground state energy of polyacetylene are presented
which demonstrate the practical usefulness of extrapolation methods.

</DOC>
<DOC>
<DOCNO> 7873 </DOCNO>
Taxonomy of Stock Market Indices


  We investigate sets of financial non-redundant and nonsynchronously recorded
time series. The sets are composed by a number of stock market indices located
all over the world in five continents. By properly selecting the time horizon
of returns and by using a reference currency we find a meaningful taxonomy. The
detection of such a taxonomy proves that interpretable information can be
stored in a set of nonsynchronously recorded time series.

</DOC>
<DOC>
<DOCNO> 119999 </DOCNO>
Four Years of Extreme Ultraviolet Observations of Markarian 421: II.


  The Extreme Ultraviolet Explorer (EUVE) satellite accumulated ~one million
seconds of public data between 1994 and 1997 for the BL Lacertae object
Markarian 421. This is the second of two papers in which we present the results
of spectral and temporal analysis of this EUVE data set. We analyze in the
present paper the imaging data by means of power spectrum and structure
function techniques, while the spectral analysis is presented in a companion
paper. We find for MRK 421 a power spectrum with slope -2.14 +- 0.28 with a
break at ~3 days. This is the first time that a break in the power spectrum of
a BL Lacertae object has been found. We also find evidence of non-stationarity
for MRK 421 EUV emission

</DOC>
<DOC>
<DOCNO> 11427 </DOCNO>
Hamiltonian structure of thermodynamics with gauge


  The state of a thermodynamic system being characterized by its set of
extensive variables $q^{i}(i=1,...,n) ,$ we write the associated intensive
variables $\gamma_{i},$ the partial derivatives of the entropy $
S(q^{1},...,q^{n}) \equiv q_{0},$ in the form $\gamma_{i}=-p_{i}/p_{0}$ where
$p_{0}$ behaves as a gauge factor. When regarded as independent, the variables
$q^{i},p_{i}(i=0,...,n) $ define a space $\mathbb{T}$ having a canonical
symplectic structure where they appear as conjugate. A thermodynamic system is
represented by a $n+1$-dimensional gauge-invariant Lagrangian submanifold
$\mathbb{M}$ of $\mathbb{T}.$ Any thermodynamic process, even dissipative,
taking place on $\mathbb{M}$ is represented by a Hamiltonian trajectory in
$\mathbb{T},$ governed by a Hamiltonian function which is zero on $\mathbb{M}.$
A mapping between the equations of state of different systems is likewise
represented by a canonical transformation in $\mathbb{T}.$ Moreover a natural
Riemannian metric exists for any physical system, with the $q^{i}$'s as
contravariant variables, the $p_{i}$'s as covariant ones. Illustrative examples
are given.

</DOC>
<DOC>
<DOCNO> 13232 </DOCNO>
Phase interference in antiferromagnetic quantum tunneling with an


  The quantum interference effects induced by the topological phase are studied
analytically in biaxial antiferromagnets with an external magnetic field at an
arbitrarily angle. This study provides a nontrivial generalization of the
Kramers degeneracy for equivalent double-well system to coherently spin
tunneling at ground states as well as low-lying excited states for
antiferromagnetic system with asymmetric twin barriers. The spin-phase
interference effects are found to depend on the orientation of the magnetic
field distinctly.

</DOC>
<DOC>
<DOCNO> 68553 </DOCNO>
Two-Loop Contribution to High Mass Dilepton Production by Quark-Gluon


  We calculate the order \alpha_s finite temperature correction to dilepton
production in quark-gluon plasma arising from the two-loop photon self-energy
diagrams for high invariant mass M >> T.

</DOC>
<DOC>
<DOCNO> 68902 </DOCNO>
Nuclear beta-decay, Atomic Parity Violation, and New Physics


  Determinations of vuds with super-allowed Fermi beta-decay in nuclei and of
the weak charge of the cesium in atomic parity-violation deviate from the
Standard Model predicitions by 2 sigma or more. In both cases, the Standard
Model over-predicts the magnitudes of the relevant observables. I discuss the
implications of these results for R-parity violating (RPV) extensions of the
minimal supersymmetric Standard Model. I also explore the possible consequences
for RPV supersymmetry of prospective future low-energy electroweak
measurements.

</DOC>
<DOC>
<DOCNO> 118202 </DOCNO>
Observations of Faint, Hard-Band X-ray Sources in the Field of CRSS


  We present results from a study of 2-8 keV X-ray sources detected by the
Advanced CCD Imaging Spectrometer (ACIS) instrument on the Chandra X-ray
Observatory in the field of the z=0.516 cluster CRSS J0030.5+2618. In our 63.5
arcmin^2 search area, we detect 10 sources with 2-8 keV fluxes down to
approximately 4x10^{-15} erg cm^{-2} s$^{-1}; our lowest flux sources are
approximately 10 times fainter than those previously available for study in
this band. Our derived source density is about an order of magnitude larger
than previous source counts above 2 keV, although this density may be enhanced
somewhat due to the presence of the cluster. We detail our methods for source
detection and characterization, and we show that the resulting source list and
parameters are robust. We have used the Marcario Low Resolution Spectrograph on
the Hobby-Eberly Telescope to obtain optical spectra for several of our
sources; combining these spectra with archival data we find that the sources
appear to be active galaxies, often with narrow permitted lines, red optical
continua or hard X-ray spectra. Four of the X-ray sources are undetected to
R=21.7; if they reside in L* galaxies they must have z > 0.55-0.75 and hard
X-ray luminosities of L_{2-8} > 4x10^{42} erg s^{-1}. We detect all but one of
our 2-8 keV sources in the 0.2-2 keV band as well. This result extends to
significantly lower fluxes the constraints on any large, completely new
population of X-ray sources that appears above 2-3 keV.

</DOC>
<DOC>
<DOCNO> 121005 </DOCNO>
Cosmological Relativity: A New Theory of Cosmology


  A general-relativistic theory of cosmology, the dynamical variables of which
are those of Hubble's, namely distances and redshifts, is presented. The theory
describes the universe as having a three-phase evolution with a decelerating
expansion followed by a constant and an accelerating expansion, and it predicts
that the universe is now in the latter phase. The theory is actually a
generalization of Hubble's law taking gravity into account by means of
Einstein's theory of general relativity. The equations obtained for the
universe expansion are elegant and very simple. It is shown, assuming
Omega_0=0.24, that the time at which the universe goes over from a decelerating
to an accelerating expansion, i.e. the constant expansion phase, occurs at
0.03tau from the big bang, where tau is the Hubble time in vacuum. Also, at
that time the cosmic radiation temperature was 11K. Recent observations of
distant supernovae imply, in defiance of expectations, that the universe growth
is accelerating, contrary to what has always been assumed that the expansion is
slowing down due to gravity. Our theory confirms these recent experimental
results by showing that the universe now is definitely in a stage of
accelerating expansion.

</DOC>
<DOC>
<DOCNO> 71172 </DOCNO>
Wide Angle Compton Scattering


  We present the handbag contribution to Wide Angle Compton Scattering (WACS)
at moderately large momentum transfer obtained with a proton distribution
amplitude close to the asymptotic form. In comparison it is found to be
significantly larger than results from the hard scattering (pQCD) approach.

</DOC>
<DOC>
<DOCNO> 8656 </DOCNO>
An equation of state {\em \`a la} Carnahan-Starling for a


  The equation of state for five-dimensional hard hyperspheres arising as a
weighted average of the Percus-Yevick compressibility (3/5) and virial (2/5)
equations of state is considered. This Carnahan-Starling-like equation turns
out to be extremely accurate, despite the fact that both Percus-Yevick
equations of state are rather poor.

</DOC>
<DOC>
<DOCNO> 150718 </DOCNO>
A Critical Cosmological Constant from Millimeter Extra Dimensions


  We consider `brane universe' scenarios with standard-model fields localized
on a 3-brane in 6 spacetime dimensions. We show that if the spacetime is
rotationally symmetric about the brane, local quantities in the bulk are
insensitive to the couplings on the brane. This potentially allows
compactifications where the effective 4-dimensional cosmological constant is
independent of the couplings on the 3-brane. We consider several possible
singularity-free compactification mechanisms, and find that they do not
maintain this property. We also find solutions with naked spacetime
singularities, and we speculate that new short-distance physics can become
important near the singularities and allow a compactification with the desired
properties. The picture that emerges is that standard-model loop contributions
to the effective 4-dimensional cosmological constant can be cut off at
distances shorter than the compactification scale. At shorter distance scales,
renormalization effects due to standard-model fields renormalize the 3-brane
tension, which changes a deficit angle in the transverse space without
affecting local quantities in the bulk. For a compactification scale of order
10^{-2} mm, this gives a standard-model contribution to the cosmological
constant in the range favored by cosmology.

</DOC>
<DOC>
<DOCNO> 120083 </DOCNO>
Resolving the Structure of Cold Dark Matter Halos II


  We study the effects of mass and force resolution on the density profiles of
galaxy-size Cold Dark Matter (CDM) halos in a flat, low-density cosmological
model with vacuum energy. We show thatalthough increasing the mass and force
resolution allows us to probe deeper into the inner halo regions, it does not
lead to steeper inner density profiles. Instead, the halo profiles converge at
scales larger than four times the formal resolution or the radius containing
more than 200 particles, whichever is larger. In the simulations presented in
this paper, we are able to probe density profile of a relaxed isolated
galaxy-size halo at scales r=(0.005-1)r_vir. We find that the density
distribution can be well approximated by the profile suggested by Moore etal
(1998): rho= x^{-1.5}(1+x^{1.5})^-1, where x=r/r_s and r_s is the
characteristic radius. The analytical profile proposed by Navarro et al. (1996)
rho= x^{-1}(1+x)^-2, also provides a good fit, with the same relative errors of
about 10% for radii larger than 1% of the virial radius. Both analytical
profiles fit equally well because for high-concentration galaxy-size halos the
differences between these profiles become significant only at scales well below
0.01r_vir. We also find that halos of similar mass may have somewhat different
parameters (characteristic radius, maximum rotation velocity, etc.) and shapes
of their density profiles. We associate this scatter in properties with
differences in halo merger histories and the amount of substructure present in
the analyzed halos.

</DOC>
<DOC>
<DOCNO> 121827 </DOCNO>
Broad band properties of medium and low Lx/Lb Early Type Galaxies


  We have measured the spectral properties of five galaxies of low to
intermediate Lx/Lb ratios with BeppoSAX and ASCA. A hard component (kT ~4-10
keV) is observed in all galaxies. In NGC1553 the BeppoSAX data show that this
component is extended, and suggest an origin for the emission in the evolved
stellar population. In NGC3115, a point-like source appears embedded in an
extended component morphologically similar to the stellar body, suggesting an
almost equal contribution from the nuclear region and the binary population. A
large central mass concentration and low level optical activity in NGC3379
argue for a contribution from the nucleus also in this object. However, for
both NGC3115 and NGC3379 the nuclear emission is at a level well below that
observed in other galaxies who host similar nuclear black holes. A second soft
(kT ~0.3-0.7 keV) spectral component is needed to fit the data of NGC1407,
NGC1553 and NGC4125 over the entire energy range probed (about 0.2-10 keV),
best represented by a thermal component with line emission. We discuss possible
interpretations of the origin of this component, which however will be better
defined only with higher quality data.

</DOC>
<DOC>
<DOCNO> 178772 </DOCNO>
Strange quark matter: mapping QCD lattice results to finite baryon


  A quasi-particle model is presented which describes QCD lattice results for
the 0, 2 and 4 quark-flavor equation of state. The results are mapped to finite
baryo-chemical potentials. As an application of the model we make a prediction
of deconfined matter with appropriate inclusion of strange quarks and consider
pure quark stars.

</DOC>
<DOC>
<DOCNO> 101800 </DOCNO>
Combinatorial and algebraic structure in Orlik-Solomon algebras


  The Orlik-Solomon algebra ${\cal A}(G)$ of a matroid $G$ is the free exterior
algebra on the points, modulo the ideal generated by the circuit boundaries. On
one hand, this algebra is a homotopy invariant of the complement of any complex
hyperplane arrangement realizing $G$. On the other hand, some features of the
matroid $G$ are reflected in the algebraic structure of ${\cal A}(G)$.
  In this mostly expository article, we describe recent developments in the
construction of algebraic invariants of ${\cal A}(G)$. We develop a categorical
framework for the statement and proof of recently discovered isomorphism
theorems which suggests a possible setting for classification theorems. Several
specific open problems are formulated.

</DOC>
<DOC>
<DOCNO> 99741 </DOCNO>
Solutions of the Einstein-Dirac Equation on Riemannian 3-Manifolds with


  This paper contains a classification of all 3-dimensional manifolds with
constant scalar curvature $S \not= 0$ that carry a non-trivial solution of the
Einstein-Dirac equation.

</DOC>
<DOC>
<DOCNO> 120615 </DOCNO>
Multicolor Observations of a Planetary Transit of HD 209458


  We present B, V, R, I and Z-band photometric observations of HD 209458 during
the transit by its planetary companion on UT 1999 November 15 with the
University of Hawaii 0.6m and 2.2m telescopes and the High Altitude Observatory
STARE telescope. The detailed shape of the transit curve is predicted to vary
with color due primarily to the color-dependent limb-darkening of the star, but
potentially due as well to the effect of color-dependent opacity in the
planetary atmosphere. We model the light curves and present refined values for
the transit timing and orbital period, useful for planning future observations
of the planetary transit. We also derive significantly improved measurements of
the planetary radius, R_p = 1.55 +/- 0.10 R_Jup, stellar radius, R_s = 1.27 +/-
0.05 R_Sun, and orbital inclination, i = 85.9 +/- 0.5 deg. The derived
planetary radius favors evolutionary models in which the planet has a low
albedo.

</DOC>
<DOC>
<DOCNO> 120966 </DOCNO>
A Submillimeter Study of the Star-Forming Region NGC7129


  New molecular (13CO J=3-2) and dust continuum (450 and 850 micron) SCUBA maps
of the NGC7129 star forming region are presented, complemented by C18O J=3-2
spectra at several positions within the mapped region. The maps include the
Herbig Ae/Be star LkHalpha 234, the far-infrared source NGC 7129 FIRS2 and
several other pre-stellar sources embedded within the molecular ridge.
  The SCUBA maps help us understand the nature of the pre-main sequence stars
in this actively star forming region. A deeply embedded submillimeter source,
SMM2, not clearly seen in any earlier data set, is shown to be a pre-stellar
core or possibly a protostar. The highest continuum peak emission is identified
with the deeply embedded source IRS6, a few arcseconds away from LkHalpha 234,
and also responsible for both the optical jet and the molecular outflow. The
gas and dust masses are found to be consistent, suggesting little or no CO
depletion onto grains. The dust emissivity index is lower towards the dense
compact sources, beta ~1 - 1.6, and higher, beta ~ 2.0, in the surrounding
cloud, implying small size grains in the PDR ridge, whose mantles have been
evaporated by the intense UV radiation.

</DOC>
<DOC>
<DOCNO> 118309 </DOCNO>
Problems encountered in the Hipparcos variable stars analysis


  Among the 17 volumes of results from the Hipparcos space mission, two are
dedicated to variable stars. These two volumes arose from the work of two
groups, one at the Geneva Observatory and one at RGO (Royal Greenwich
Observatory), on the 13 million photometric measurements produced by the
satellite for 118204 stars.
  The analysis of photometric time series permitted us to identify several
instrumental and mathematical problems: overestimation of the precision,
offsets in the zero-points depending on the field of view, mispointing effects,
image superpositions, trends in the magnitudes, binarity effects (spurious
periods and amplitudes) and time-sampling effects. In this article we summarize
some of the problems encountered by the Geneva group.

</DOC>
<DOC>
<DOCNO> 123052 </DOCNO>
Emission line imaging of QSOs with high resolution


  We report the first detection of emission line gas within the host galaxies
of high redshift QSOs. This was done using narrow-band imaging at the
redshifted wavelengths of [O III] and H alpha, using the PUEO adaptive optics
camera of the CFHT. The QSOs are all radio-quiet or very compact radio sources.
In all five observed QSOs, which have redshifts 0.9 to 2.4, we find extended
line emission that lies within 0.5" (a few Kpc) of the nucleus. The emission
(redshifted) equivalent widths range from 35 to 300A. Where there is radio
structure, the line emission is aligned with it. We also report on continuum
fluxes and possible companions. Two of the QSOs are very red, and have high
resolved continuum flux.

</DOC>
<DOC>
<DOCNO> 99909 </DOCNO>
A two-box-shift morphism between Specht modules


  Let n geq 1, let lambda be a partition of n, let mu be a partition arising
from lambda by a downwards shift of two boxes situated at the bottom of a
column. We give a formula for a ZS_n-linear morphism of order m between the
corresponding Specht modules over Z/(m), where m is the box shift length
(divided by two in certain combinatorially specified cases). Reformulated, this
yields an extension of the corresponding Specht modules over Z of order m in
Ext^1.

</DOC>
<DOC>
<DOCNO> 100671 </DOCNO>
Optimistic calculations about the Witten--Reshetikhin--Turaev invariants


  I calculate optimistically asymptotic behaviors of the WRT SU(2) invariants
for the three-manifolds obtained from the figure-eight knot by p-surgeries with
p=0,1,2,...,10, from which one can extract volumes and the Chern-Simons
invariants of these closed manifolds. I conjecture that this also holds for
general closed three-manifolds.

</DOC>
<DOC>
<DOCNO> 10203 </DOCNO>
Collective modes in uniaxial incommensurate-commensurate systems with


  The basic Landau model for uniaxial systems of the II class is nonintegrable,
and allows for various stable and metastable periodic configurations, beside
that representing the uniform (or dimerized) ordering. In the present paper we
complete the analysis of this model by performing the second order variational
procedure, and formulating the combined Floquet-Bloch approach to the ensuing
nonstandard linear eigenvalue problem. This approach enables an analytic
derivation of some general conclusions on the stability of particular states,
and on the nature of accompanied collective excitations. Furthermore, we
calculate numerically the spectra of collective modes for all states
participating in the phase diagram, and analyze critical properties of
Goldstone modes at all second order and first order transitions between
disordered, uniform and periodic states. In particular it is shown that the
Goldstone mode softens as the underlying soliton lattice becomes more and more
dilute.

</DOC>
<DOC>
<DOCNO> 68736 </DOCNO>
Three Inequivalent Mass-Degenerate Majorana Neutrinos and a Model of


  The mass matrix of three Majorana neutrinos of equal mass is not necessarily
proportional to the identity matrix, but expressible in terms of two angles and
one phase. We discuss how such a mass matrix may be stable or unstable against
radiative corrections. We then propose a model with additional explicit
breaking of the threefold degeneracy to account for the atmospheric neutrino
data, while the radiative breaking explains the solar neutrino data, using the
large-angle Mikheyev-Smirnov-Wolfenstein solution. Our model requires a nonzero
effective $\nu_e$ mass for neutrinoless double beta decay close to the present
experimental upper limit of 0.2 eV.

</DOC>
<DOC>
<DOCNO> 83401 </DOCNO>
Design of an Electro-Hydraulic System Using Neuro-Fuzzy Techniques


  Increasing demands in performance and quality make drive systems fundamental
parts in the progressive automation of industrial processes. Their conventional
models become inappropriate and have limited scope if one requires a precise
and fast performance. So, it is important to incorporate learning capabilities
into drive systems in such a way that they improve their accuracy in realtime,
becoming more autonomous agents with some degree of intelligence. To
investigate this challenge, this chapter presents the development of a learning
control system that uses neuro-fuzzy techniques in the design of a tracking
controller to an experimental electro-hydraulic actuator. We begin the chapter
by presenting the neuro-fuzzy modeling process of the actuator. This part
surveys the learning algorithm, describes the laboratorial system, and presents
the modeling steps as the choice of actuator representative variables, the
acquisition of training and testing data sets, and the acquisition of the
neuro-fuzzy inverse-model of the actuator. In the second part of the chapter,
we use the extracted neuro-fuzzy model and its learning capabilities to design
the actuator position controller based on the feedback-error-learning
technique. Through a set of experimental results, we show the generalization
properties of the controller, its learning capability in actualizing in
realtime the initial neuro-fuzzy inverse-model, and its compensation action
improving the electro-hydraulics tracking performance.

</DOC>
<DOC>
<DOCNO> 40499 </DOCNO>
Kinematic Fit for the Radiative Bhabha Calibration of BaBar's


  For the radiative Bhabha calibration of BaBar's electromagnetic calorimeter,
the measured energy of a photon cluster is being compared with the energy
obtained via a kinematic fit involving other quantities from that event. The
details of the fitting algorithm are described in this note, together with its
derivation and checks that ensure that the fitting routine is working properly.

</DOC>
<DOC>
<DOCNO> 39808 </DOCNO>
Search for Compositeness, Leptoquarks and Large Extra Dimensions in eq


  The reaction e+p --> e+X is studied with the H1 detector at Hera. The data
cover momentum transfers Q^2 between 200 GeV^2 and 30,000 GeV^2 and correspond
to an integrated luminosity of 35.6 pb^(-1). The differential cross section
dsigma/dQ^2 is compared to the Standard Model expectation for neutral current
scattering and analysed to search for bar(e)e bar(q)q contact interactions. No
evidence for new phenomena is observed. The results are used to set limits on
scales within models of electron--quark compositeness, quark form factors and
the exchange of virtual heavy leptoquarks. A search for gravitational effects
mediated through the exchange of virtual gravitons which propagate into large
extra dimensions is presented.

</DOC>
<DOC>
<DOCNO> 83376 </DOCNO>
Introduction to the CoNLL-2000 Shared Task: Chunking


  We describe the CoNLL-2000 shared task: dividing text into syntactically
related non-overlapping groups of words, so-called text chunking. We give
background information on the data sets, present a general overview of the
systems that have taken part in the shared task and briefly discuss their
performance.

</DOC>
<DOC>
<DOCNO> 70499 </DOCNO>
A new look at the pair-production width in a strong magnetic field


  We reexamine the process $\gamma\to e^++ e^-$ in a background magnetic field
comparable to $B_c\equiv m_e^2/e$. This process is known to be non-perturbative
in the magnetic-field strength. However, it can be shown that the {\it moments}
of the above pair production width is proportional to the derivatives of photon
polarization function at the zero energy, which is perturbative in $B$. Hence,
the pair-production width can be easily obtained from the latter by the inverse
Mellin transform. The implications of our approach are discussed.

</DOC>
<DOC>
<DOCNO> 119086 </DOCNO>
Gamma-Ray Bursts as a Cosmic Window for Galaxy Evolution


  Present knowledge indicates that gamma-ray bursts are linked with massive
stars. They will become invaluable probes of the early universe and galaxy
formation. In the future, it will be possible to use gamma-ray bursts for two
purposes: 1) to probe the history of massive star formation in the Universe by
the rate of occurence of gamma-ray bursts, and 2) for the study of galaxy
evolution at all lookback times by determining the nature of the galaxy hosts.
Because gamma-rays are not attenuated by intervening dust and gas, the
selection of the cosmic sites of massive star formation by this method is less
affected by the biases associated with optical-uv surveys (e.g. UV-dropout
techniques). Infrared and sub-millimeter follow up studies of the hosts of
gamma-ray bursts may: 1) reveal a putative population of reddened ($R-K \geq
4$) galaxies at high redshifts, and 2) detect very massive stars (population
III) formed at $z \geq$ 5.

</DOC>
<DOC>
<DOCNO> 10349 </DOCNO>
Constraints on the Quasiparticle Density of States in High-$T_c$


  In this Letter we present new tunneling data on YBa$_2$Cu$_3$O$_7$ thin films
by low temperature scanning tunneling spectroscopy. Unusual peak-dip-hump
features, previously reported in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$, are also
found in YBa$_2$Cu$_3$O$_7$. To analyse these common signatures we propose a
new heuristic model in which, in addition to the d-wave symmetry, the gap
function is energy dependent. A simple expression for the quasiparticle density
of states is derived, giving an excellent agreement with the experiment. The
dynamics of the quasiparticle states and the energy scales involved in the
superconducting transition are discussed.

</DOC>
<DOC>
<DOCNO> 10377 </DOCNO>
Unoccupied electronic states of Au(113): theory and experiment


  We present results from Inverse photoemission spectroscopy in the isochromat
mode, with angular resolution, from the clean Au(113) surface. To identify the
origin of the different resonances we have performed first principles
calculations of the bulk band structure in the LMTO formalism. Using the
particular characteristic of the spectrometer we have made a theoretical
prediction of the bulk features dispersion as a function of parallel momentum,
considering only energy and momentum conservation. Thus we have been able to
unambiguously identify, from measured spectra various bulk derived resonances
in addition to two surface resonances and a surface state in the [-110] and
[33-2] directions respectively.

</DOC>
<DOC>
<DOCNO> 122168 </DOCNO>
Discovery of Two Relativistic Neutron Star-White Dwarf Binaries


  We have discovered two recycled pulsars in relativistic orbits as part of the
first high-frequency survey of intermediate Galactic latitudes. PSR J1157-5112
is a 44 ms pulsar and the first recycled pulsar with an ultra-massive (M > 1.14
Mo) white dwarf companion. Millisecond pulsar J1757-5322 is a relativistic
circular-orbit system which will coalesce due to the emission of gravitational
radiation in less than 9.5 Gyr. Of the ~40 known circular orbit pulsars,
J1757-5322 and J1157-5112 have the highest projected orbital velocities. There
are now three local neutron-star/white-dwarf binaries that will coalesce in
less than a Hubble time, implying a large coalescence rate for these objects in
the local Universe. Systems such as J1141-6545 (Kaspi et al. 2000) are
potential gamma-ray burst progenitors and dominate the coalescence rate, whilst
lighter systems make excellent progenitors of millisecond pulsars with
planetary or ultra-low mass companions.

</DOC>
<DOC>
<DOCNO> 118006 </DOCNO>
Heliospheric, Astrospheric, and Insterstellar Lyman-alpha Absorption


  We use high-resolution UV spectra taken by the Space Telescope Imaging
Spectrograph instrument on board the Hubble Space Telescope to study the 5.5 pc
line of sight to the K0 V star 36 Oph A. The one interstellar component
detected for this line of sight has a velocity inconsistent with the local
interstellar cloud (LIC) flow vector, but consistent with the flow vector of
the so-called G cloud, a very nearby warm cloud in the Galactic Center
direction. From our data, we measure the following values for the interstellar
temperature, nonthermal velocity, H I column density, and D/H value:
T=5900+/-500 K, xi=2.2+/-0.2$ km/s, log N(H)=17.85+/-0.15, and
D/H=(1.5+/-0.5)e-5. The temperature of the G cloud is somewhat lower than that
of the LIC, and Mg and Fe depletions are also lower, but the D/H value appears
to be the same. Based on upper limits for the LIC absorption, we estimate the
distance to the edge of the LIC to be d(edge)<0.19 pc, which the Sun will reach
in t(edge)<7400 yrs. The H I Lyman-alpha absorption line has properties
inconsistent with those of the other absorption lines, indicating the presence
of one or more absorption components not seen in the other lines. We present
evidence that hot neutral hydrogen local to both the Sun and the star is
responsible for the excess Lyman-alpha absorption. This hot H I is created by
the interaction between the ISM and the winds of the Sun and 36 Oph A. The
observed line of sight lies only 12 degrees from the upwind direction of the
LIC flow vector, where hydrodynamic models of the heliosphere suggest that
heliospheric H I absorption should be particularly prominent.

</DOC>
<DOC>
<DOCNO> 118924 </DOCNO>
X-ray Sources in the Hubble Deep Field Detected by Chandra


  We present first results from an X-ray study of the Hubble Deep Field North
(HDF-N) and its environs obtained using 166 ks of data collected by the
Advanced CCD Imaging Spectrometer (ACIS) on board the Chandra X-ray
Observatory. This is the deepest X-ray observation ever reported, and in the
HDF-N itself we detect six X-ray sources down to a 0.5--8 keV flux limit of
4E-16 erg cm^-2 s^-1. Comparing these sources with objects seen in
multiwavelength HDF-N studies shows positional coincidences with the extremely
red object NICMOS J123651.74 +621221.4, an active galactic nucleus (AGN), three
elliptical galaxies, and one nearby spiral galaxy. The X-ray emission from the
ellipticals is consistent with that expected from a hot interstellar medium,
and the spiral galaxy emission may arise from a `super-Eddington' X-ray binary
or ultraluminous supernova remnant. Four of the X-ray sources have been
detected at radio wavelengths. We also place X-ray upper limits on AGN
candidates found in the HDF-N, and we present the tightest constraints yet on
X-ray emission from the SCUBA submillimeter source population. None of the 10
high-significance submillimeter sources reported in the HDF-N and its vicinity
is detected with Chandra ACIS. These sources appear to be dominated by star
formation or have AGN with Compton-thick tori and little circumnuclear X-ray
scattering.

</DOC>
<DOC>
<DOCNO> 117496 </DOCNO>
Ammonia observations of the nearby molecular cloud MBM 12


  We present NH3(1,1) and NH3(2,2) observations of MBM 12, the closest known
molecular cloud (65 pc distance), aimed to find evidence for on-going star
formation processes. No local temperature (with a T_rot upper limit of 12 K)
nor linewidth enhancement is found, which suggests that the area of the cloud
we mapped (~ 15' size) is not currently forming stars. Therefore, this close
``starless'' molecular gas region is an ideal laboratory to study the physical
conditions preceding new star formation.
  A radio continuum source was found in Very Large Array archive data, close
but outside the NH3 emission. This source is likely to be a background object.

</DOC>
<DOC>
<DOCNO> 102588 </DOCNO>
Real hyperelliptic surfaces and the orbifold fundamental group


  In this paper we finish the topological classification of real algebraic
surfaces of Kodaira dimension zero and we make a step towards the Enriques
classification of real algebraic surfaces, by describing in detail the
structure of the moduli space of real hyperelliptic surfaces.
  Moreover, we point out the relevance in real geometry of the notion of the
orbifold fundamental group of a real variety, and we discuss related questions
on real varieties $(X, \sigma)$ whose underlying complex manifold $X$ is a $K
(\pi, 1)$.
  Our first result is that if $(S, \sigma)$ is a real hyperelliptic surface,
then the differentiable type of the pair $(S, \sigma)$ is completely determined
by the orbifold fundamental group exact sequence. This result allows us to
determine all the possible topological types of $(S, \sigma)$, and to prove
that they are exactly 78.
  It follows also as a corollary that there are exactly eleven cases for the
topological type of the real part of S.
  Finally, we show that once we fix the topological type of $(S, \sigma)$
corresponding to a real hyperelliptic surface, the corresponding moduli space
is irreducible (and connected).
  We also give, through a series of tables, explicit analytic representations
of the 78 components of the moduli space.

</DOC>
<DOC>
<DOCNO> 150447 </DOCNO>
D-brane effective field theory from string field theory


  Open string field theory is considered as a tool for deriving the effective
action for the massless or tachyonic fields living on D-branes. Some simple
calculations are performed in open bosonic string field theory which validate
this approach. The level truncation method is used to calculate successive
approximations to the quartic terms \phi^4, (A^\mu A_\mu)^2 and [A_\mu,
A_\nu]^2 for the zero momentum tachyon and gauge field on one or many bosonic
D-branes. We find that the level truncation method converges for these terms
within 2-4% when all massive fields up to level 20 are integrated out, although
the convergence is slower than exponential. We discuss the possibility of
extending this work to determine the structure of the nonabelian Born-Infeld
theory describing the gauge field on a system of many parallel bosonic or
supersymmetric D-branes. We also describe a brane configuration in which
tachyon condensation arises in both the gauge theory and string field theory
pictures. This provides a natural connection between recent work of Sen and
Zwiebach on tachyon condensation in string field theory and unstable vacua in
super Yang-Mills and Born-Infeld field theory.

</DOC>
<DOC>
<DOCNO> 102686 </DOCNO>
A Rigorous Real Time Feynman Path Integral


  Using improper Riemann integrals, we will formulate a rigorous version of the
real-time, time-sliced Feynman path integral for the $L^2$ transition
probability amplitude. We will do this for nonvector potential Hamiltonians
with potential which has at most a finite number of discontinuities and
singularities. We will also provide a Nonstandard Analysis version of our
formulation.

</DOC>
<DOC>
<DOCNO> 71732 </DOCNO>
Molecular status of non-qq mesons


  The relativistic four-quark equations are found in the framework of the
dispersion relation technique. The calculations of non-qq meson amplitudes
estimate the contributions of three subamplitudes: four-quark amplitude,
glueball amplitude and hadronic molecule amplitudes.

</DOC>
<DOC>
<DOCNO> 120157 </DOCNO>
The Surroundings of Disturbed, Active Galaxies


  The brightest apparent magnitude examples of ultra luminous infrared galaxies
(ULIRG's) are studied here in X-ray, optical, infrared and radio wavelengths.
It is is found that they have associated material reaching out to apparent
diameters of the order of a degree on the sky.
  Gas, dust, X-ray material and quasars appear to be ejected from the active
nuclei with all objects nearer than their redshift distances.

</DOC>
<DOC>
<DOCNO> 11855 </DOCNO>
Critical branching-annihilating random walk of two species


  The effect of blocking between different species occurring in one dimension
is investigated here numerically in the case of particles following branching
and annihilating random walk with two offsprings. It is shown that
two-dimensional simulations confirm the field theoretical results with
logarithmic corrections. In one dimension, however, if particles exhibit hard
core interaction I confirm the very recent predictions of Kwon et al. [PRL {\bf
85}, 1682 (2000)] that there are two different universality classes depending
on the spatial symmetry of the offspring production characterized by
$\beta_S=0.5$ and $\beta_A=2$. Elaborate analysis of simulation data shows that
the order parameter exponent $\beta$ does not depend on initial conditions or
on diffusion rates of species but strong correction to scaling is observed. By
systematic numerical simulations the critical point properties have been
explored and initial condition dependence of the dynamical exponents $Z$ and
$\alpha$ is shown. In the case of a random initial state the particle-density
decay at the critical point follows the $t^{-1/4}$ law with logarithmic
corrections.

</DOC>
<DOC>
<DOCNO> 120811 </DOCNO>
Doppler Tomography of XTE J2123-058 and Other Neutron Star LMXBs


  We describe Doppler tomography obtained in the 1998 outburst of the neutron
star low mass X-ray binary (LMXB) XTE J2123-058. This analysis, and other
aspects of phase-resolved spectroscopy, indicate similarities to SW Sex
systems, except that anomalous emission kinematics are seen in HeII, whilst
phase 0.5 absorption is confined to H alpha. This separation of these effects
may provide tighter constraints on models in the LMXB case than is possible for
SW Sex systems. We will compare results for other LMXBs which appear to show
similar kinematics and discuss how models for the SW Sex phenomenon can be
adapted to these systems. Finally we will summarise the limited Doppler
tomography performed on the class of neutron star LMXBs as a whole, and discuss
whether any common patterns can yet be identified.

</DOC>
<DOC>
<DOCNO> 123311 </DOCNO>
Jets, Disks and Spectral States of Black Holes


  We show that outflow rates in jets directly depend on the spectral states of
black holes. In particular, in soft states, when the Comptonized electrons are
cold, outflow rate is close to zero. In hard states, outflow could be steady,
but the rate may be very small -- only a few percent of the inflow. In the
intermediate states, on the other hand, the outflow rate is the highest --
roughly thirty percent of the inflow. In this case, piled up matter below the
sonic surface of the outflow could become optically thick and radiative
processes could periodically cool the outflow and produce very interesting
effects including transitions between burst (high-count or On) and quiescence
(low-count or Off) states such as those observed in GRS 1915+105.

</DOC>
<DOC>
<DOCNO> 13492 </DOCNO>
Stretched exponential relaxation in the mode-coupling theory for the


  We study the mode-coupling theory for the Kardar-Parisi-Zhang equation in the
strong-coupling regime, focusing on the long time properties. By a saddle point
analysis of the mode-coupling equations, we derive exact results for the
correlation function in the long time limit - a limit which is hard to study
using simulations. The correlation function at wavevector k in dimension d is
found to behave asymptotically at time t as C(k,t)\simeq 1/k^{d+4-2z}
(Btk^z)^{\gamma/z} e^{-(Btk^z)^{1/z}}, with \gamma=(d-1)/2, A a determined
constant and B a scale factor.

</DOC>
<DOC>
<DOCNO> 117525 </DOCNO>
Extended Gas in Seyfert Galaxies: Near-Infrared Observations of 15


  Results from an analysis of low resolution (R~250) near-IR long-slit spectra
covering simultaneously the I, J, H, and K bands, for a sample of 15 Seyfert
galaxies and the N5253 starburst nucleus, are presented. The Seyfert galaxies
were selected as presenting `linear' or cone-like high excitation emission line
in the optical, most probably due to the collimation of the central source's
radiation by a dusty molecular torus. Our goal was to look for signatures of
this torus, and to investigate the gaseous distribution, excitation and
reddening. The IR emission lines are spatially extended in most cases, and we
have used the [FeII]/Pa(beta) ratio as a measure of the gaseous excitation in
Mrk573, N1386, and N7582. Values for this ratio between 1.5 and 6 are found,
suggesting excitation of [FeII] by X-rays or shock waves in some regions.
Nuclear Pa(beta) in N1365, and possibly nuclear Br(gama) in Mrk573, are broad.
  From analysis of the spatial distribution of the continuum (J-H) and (H-K)
colours derived from our spectra, we find redder colours for the nucleus than
the nearby bulge in most of the Seyfert 2s observed. Comparison with models
including emission from dust and stars shows that hot (T~1000 K) dust emission
dominates the nuclear continuum in N1365, N2110, N3281, N7582, and ESO362-G18.
In N1386, N5643, and N5728 the main contributor is the underlying stellar
population, combined with some foreground reddening and/or cool dust emission.
In a few cases, the (J-H) colours on opposite sides of the nucleus differ by
0.3-0.8 mag, an effect that we interpret as partly due to differences in the
local stellar population, and possibly extinction gradients.

</DOC>
<DOC>
<DOCNO> 150471 </DOCNO>
Questions in quantum physics: a personal view


  An assessment of the present status of the theory, some immediate tasks which
are suggested thereby and some questions whose answers may require a longer
breath since they relate to significant changes in the conceptual and
mathematical structure of the theory.

</DOC>
<DOC>
<DOCNO> 118407 </DOCNO>
A simple, stringent test on the nature of GRBs' progenitors


  I show here that the time-delay between the gamma ray burst proper and the
onset of the afterglow is a sensitive function of the surrounding density,
going from ~10s for typical disk densities to several hours for IGM densities.
Since bulk Lorenz factor, explosion energy and environment density can be
simultaneously determined from observations of the time-delay and of the
afterglow, afterglow observations alone may establish which fraction, if any,
of all bursts resides inside galaxies, in their outer haloes, or outright in
the IGM medium, subjecting the NS/NS merger hypothesis to a definitive test. If
bursts are due to collapse of massive stars, no matter how short the burst, the
onset of the afterglow should be immediate.

</DOC>
<DOC>
<DOCNO> 68900 </DOCNO>
Static correlation lengths in QCD at high temperatures and finite


  We use a perturbatively derived effective field theory and three-dimensional
lattice simulations to determine the longest static correlation lengths in the
deconfined QCD plasma phase at high temperatures (T\gsim 2 Tc) and finite
densities (\mu\lsim 4 T). For vanishing chemical potential, we refine a
previous determination of the Debye screening length, and determine the
dependence of different correlation lengths on the number of massless flavours
as well as on the number of colours. For non-vanishing but small chemical
potential, the existence of Debye screening allows us to carry out simulations
corresponding to the full QCD with two (or three) massless dynamical flavours,
in spite of a complex action. We investigate how the correlation lengths in the
different quantum number channels change as the chemical potential is switched
on.

</DOC>
<DOC>
<DOCNO> 121029 </DOCNO>
A New interpretation of chain galaxies at high redshift


  We propose a possible new model for the formation of chain galaxies at high
redshift. Our model is summarized as follows. Step I: Successive merging of
subgalactic gas clumps results in the formation of a galaxy with a mass of
$10^{11-12} M_\odot$ at redshift $z \sim 5$. Step II: Subsequently, supernova
explosions occur inside the galaxy and then blow out as a galactic wind (or a
superwind). This wind expands into the intergalactic space and then causes a
large-scale shell with a radius of several hundreds of kpc. Since this radius
may be smaller than the typical separation between galaxies, interactions of
shells may also occur, resulting in the formation of a large-scale gaseous
slab. Step III: Since the shell or the slab can be regarded as a gaseous sheet,
filament-like gravitational instability is expected to occur. Step IV: Further
gravitational instability occurs in each filament, leading to intense star
formation along the filament. This is the chain galaxy phase. Step V: The
filament collapses gravitationally into one spheroidal system like an
elliptical galaxy within one dynamical timescale of the filament ($\sim 10^8$
yr). Therefore, it seems quite difficult to find remnants of chain galaxies. We
also discuss that shocked shells driven by superwinds may be responsible for
some Lyman limit systems and damped Ly$\alpha$ systems because their H {\sc i}
column densities are expected to be $N_{\rm HI} \gtrsim 10^{19}$ cm$^{-2}$.

</DOC>
<DOC>
<DOCNO> 7635 </DOCNO>
Replica-exchange molecular dynamics simulation for supercooled liquids


  We investigate to what extend the replica-exchange Monte Carlo method is able
to equilibrate a simple liquid in its supercooled state. We find that this
method does indeed allow to generate accurately the canonical distribution
function even at low temperatures and that its efficiency is about 10-100 times
higher than the usual canonical molecular dynamics simulation.

</DOC>
<DOC>
<DOCNO> 80692 </DOCNO>
Non-Gaussian numerical errors versus mass hierarchy


  We probe the numerical errors made in renormalization group calculations by
varying slightly the rescaling factor of the fields and rescaling back in order
to get the same (if there were no round-off errors) zero momentum 2-point
function (magnetic susceptibility). The actual calculations were performed with
Dyson's hierarchical model and a simplified version of it. We compare the
distributions of numerical values obtained from a large sample of rescaling
factors with the (Gaussian by design) distribution of a random number generator
and find significant departures from the Gaussian behavior. In addition, the
average value differ (robustly) from the exact answer by a quantity which is of
the same order as the standard deviation. We provide a simple model in which
the errors made at shorter distance have a larger weight than those made at
larger distance. This model explains in part the non-Gaussian features and why
the central-limit theorem does not apply.

</DOC>
<DOC>
<DOCNO> 123058 </DOCNO>
Models of Quasi-Periodic Variability in Neutron Stars and Black Holes


  Black holes and weakly-magnetic accreting neutron stars show strong
quasi-periodic variability over timescales that span a very wide range. This
property offer us a unique opportunity to improve our understanding of basic
physical processes in strong gravitational fields as it reveals, for the first
time, phenomena that occur on the most fundamental timescales near accreting
compact objects. In this article, I review our current understanding of the
variability properties of accretion flows onto neutron stars and black holes. I
discuss a number of challenges faced by theoretical models, in order to
identify open questions in accretion physics that need to be addressed.
Finally, I discuss the relation to and implications for variability models of
the detection of nearly coherent oscillations during type I X-ray bursts in
several neutron-star sources.

</DOC>
<DOC>
<DOCNO> 170039 </DOCNO>
Characterization of separable states and entanglement witnesses


  We provide a canonical form of mixed states in bipartite quantum systems in
terms of a convex combination of a separable state and a, so-called, edge
state. We construct entanglement witnesses for all edge states. We present a
canonical form of nondecomposable entanglement witnesses and the corresponding
positive maps. We provide constructive methods for their optimization in a
finite number of steps. We present a characterization of separable states using
a special class of entanglement witnesses. Finally, we present a nontrivial
necessary condition for entanglement witnesses and positive maps to be
extremal.

</DOC>
<DOC>
<DOCNO> 68443 </DOCNO>
Tilted Pion Sources from Azimuthally Sensitive HBT Interferometry


  Intensity interferometry in noncentral heavy ion collisions provides access
to novel information on the geometry of the effective pion-emitting source. We
demonstrate analytically that, even for vanishing pair momentum, the cross
terms $R_{ol}^2$ and $R_{sl}^2$ of the HBT correlation function in general show
a strong first harmonic in their azimuthal dependence. The strength of this
oscillation characterizes the tilt of the major axis of the spatial emission
ellipsoid away from the direction of the beam. Event generator studies indicate
that this tilt can be large (>20 degrees) at AGS energies which makes it by far
the most significant azimuthally sensitive HBT signal at these energies.
Moreover, transport models suggest that for pions this spatial tilt is directed
opposite to the tilt of the directed flow ellipsoid in momentum space. A
measurement of the azimuthal dependence of the HBT cross terms $R_{ol}^2$ and
$R_{sl}^2$ thus probes directly the physical origin of directed pion flow.

</DOC>
<DOC>
<DOCNO> 70566 </DOCNO>
Charged Brane-World Black Holes


  We study charged brane-world black holes in the model of Randall and Sundrum
in which our universe is viewed as a domain wall in asymptotically anti-de
Sitter space. Such black holes can carry two types of ``charge'', one arising
from the bulk Weyl tensor and one from a gauge field trapped on the wall. We
use a combination of analytical and numerical techniques to study how these
black holes behave in the bulk. It has been shown that a Reissner-Nordstrom
geometry is induced on the wall when only Weyl charge is present. However, we
show that such solutions exhibit pathological features in the bulk. For more
general charged black holes, our results suggest that the extent of the horizon
in the fifth dimension is usually less than for an uncharged black hole that
has the same mass or the same horizon radius on the wall.

</DOC>
<DOC>
<DOCNO> 118142 </DOCNO>
Kinematics of Molecular Hydrogen Emission from Planetary and


  We report results from a program of high-resolution spectral mapping of
rotational H_2 emission from bipolar planetary and pre-planetary nebulae.
Long-slit spectra obtained with the NOAO Phoenix near-infrared spectrometer
allow us to probe the molecular kinematics of these nebulae at moderate spatial
resolution. We find strong evidence of a component of rotation in the
equatorial H_2 emission from the Egg nebula (RAFGL 2688). In this nebula and in
the pre-planetary nebula RAFGL 618, the H_2 kinematics point to the recent
emergence of high-velocity polar flows, which likely mark the fairly sudden
terminations of the red giant phases of their central stars. The classical
bipolar planetary NGC 2346 displays distinct kinematic components, which we
interpret as arising in the morphologically distinct equatorial and polar
regions of the nebula. The H_2 rings observed in the Phoenix position-velocity
maps of this nebula support the hypothesis that ring-like planetaries that
display H_2 emission possess bipolar structure.

</DOC>
<DOC>
<DOCNO> 68223 </DOCNO>
The phi --> pi^+ pi^- and phi radiative decays within a chiral unitary


  We report on recent results on the decay of the phi into pi^+ pi^- and phi
radiative decays into pi^0 pi^0 gamma and pi^0 eta gamma, which require the
consideration of the final state interaction of a pair of mesons in a region
inaccessible to Chiral Perturbation Theory. By using nonperturbative chiral
unitary methods for the meson meson interaction we can obtain the corresponding
decay widths and the results are compared with recent experimental data.

</DOC>
<DOC>
<DOCNO> 84650 </DOCNO>
Cosmic crystallography in a circle


  In a circle (an S^1) with circumference 1 assume m objects distributed
pseudo-randomly. In the universal covering R^1 assume the objects replicated
accordingly, and take an interval L>1. In this interval, make the normalized
histogram of the pair separations which are not an integer. The theoretical
(expected) such histogram is obtained in this report, as well as its difference
to a similar histogram for non-replicated objects. The whole study is of
interest for the cosmic crystallography.

</DOC>
<DOC>
<DOCNO> 151024 </DOCNO>
Intersecting domain walls in MQCD


  We argue that MQCD admits intersecting domain walls that are realized as
Cayley calibrations of the MQCD M5-brane. We discuss various dual realizations
and comment on how branes can realise domain walls in N=1 supersymmetric
theories in D=3.

</DOC>
<DOC>
<DOCNO> 84912 </DOCNO>
Collapsing Perfect Fluid in Higher Dimensional Spherical Spacetimes


  The general metric for N-dimensional spherically symmetric and conformally
flat spacetimes is given, and all the homogeneous and isotropic solutions for a
perfect fluid with the equation of state $p = \alpha \rho$ are found. These
solutions are then used to model the gravitational collapse of a compact ball.
It is found that when the collapse has continuous self-similarity, the
formation of black holes always starts with zero mass, and when the collapse
has no such a symmetry, the formation of black holes always starts with a mass
gap.

</DOC>
<DOC>
<DOCNO> 121556 </DOCNO>
Two-Dimensional MHD Numerical Simulations of Magnetic Reconnection


  We examine the magnetic reconnection triggered by a supernova (or a point
explosion) in interstellar medium, by performing two-dimensional resistive
magnetohydrodynamic (MHD) numerical simulations with high spatial resolution.
We found that the magnetic reconnection starts long after a supernova shock
(fast-mode MHD shock) passes a current sheet. The current sheet evolves as
follows: (i) Tearing-mode instability is excited by the supernova shock, and
the current sheet becomes thin in its nonlinear stage. (ii) The current-sheet
thinning is saturated when the current-sheet thickness becomes comparable to
that of Sweet-Parker current sheet. After that, Sweet-Parker type reconnection
starts, and the current-sheet length increases. (iii) ``Secondary tearing-mode
instability'' occurs in the thin Sweet-Parker current sheet. (iv) As a result,
further current-sheet thinning occurs and anomalous resistivity sets in,
because gas density decreases in the current sheet. Petschek type reconnection
starts and heats interstellar gas. Magnetic energy is released quickly while
magnetic islands are moving in the current sheet during Petschek type
reconnection. The released magnetic energy is determined by the interstellar
magnetic field strength, not energy of initial explosion nor distance to
explosion. We suggest that magnetic reconnection is a possible mechanism to
generate X-ray gas in Galaxy.

</DOC>
<DOC>
<DOCNO> 118766 </DOCNO>
A Giant Glitch in the Energetic 69 ms X-ray Pulsar AXS J161730-505505


  We present new results on the recently discovered 69 ms X-ray pulsar AXS
J161730-505505, the sixth youngest sample of all known pulsars. We have
undertaken a comprehensive X-ray observing campaign of AXS J161730-505505 with
the ASCA, SAX, and XTE observatories and follow its long term spin-down history
between 1989 and 1999, using these, archival GINGA and ASCA data sets, and the
radio ephemeris. The spin-down is not simply described by a linear function as
originally thought, but instead we find evidence of a giant glitch (|Delta P/P|
> 10E-6) between 1993 August and 1997 September, perhaps the largest yet
observed from a young pulsar. The glitch is well described by steps in the
period and its first derivative accompanied by a persistent second derivative
similar to those in the Vela pulsar. The pulse profile of AXS J161730-505505
presents a single asymmetric peak which is maintained over all observation
epochs. The energy spectrum is also steady over time, characterized by a highly
absorbed power-law with a photon index 1.4 +/- 0.2, consistent with that found
for other young rotation powered pulsars.

</DOC>
<DOC>
<DOCNO> 152409 </DOCNO>
Holographic Renormalization Group Flows: The View from Ten Dimensions


  The holographic description of supersymmetric RG flows in supergravity is
considered from both the five-dimensional and ten-dimensional perspectives. An
N=1* flow of N=4 super-Yang Mills is considered in detail, and the infra-red
limit is studied in terms of IIB supergravity in ten dimensions. Depending on
the vevs and the direction of approach to the core, the supergravity solution
can be interpreted in terms of either 5-branes or 7-branes. Generally, it is
shown that it is essential to use the ten-dimensional description in order to
study the infra-red asymptotics in supergravity.

</DOC>
<DOC>
<DOCNO> 99665 </DOCNO>
Structure and Stability of Certain Chemical Networks and Applications to


  This paper deals with the theory of structure, stability, robustness, and
stabilization for an appealing class of nonlinear systems which arises in the
analysis of chemical networks.
  The results given here extend, but are also heavily based upon, certain
previous work by Feinberg, Horn, and Jackson, of which a self-contained and
streamlined exposition is included.
  The theoretical conclusions are illustrated through an application to the
kinetic proofreading model proposed by McKeithan for T-cell receptor signal
transduction. (Update includes, among other topics, remarks on extensions to
certain systems with Michaelis-Menten kinetics.)

</DOC>
<DOC>
<DOCNO> 102479 </DOCNO>
(-1)-enumeration of plane partitions with complementation symmetry


  We compute the weighted enumeration of plane partitions contained in a given
box with complementation symmetry where adding one half of an orbit of cubes
and removing the other half of the orbit changes the weight by -1 as proposed
by Kuperberg. We use nonintersecting lattice path families to accomplish this
for transpose-complementary, cyclically symmetric transpose-complementary and
totally symmetric self-complementary plane partitions. For symmetric
transpose-complementary and self-complementary plane partitions we get partial
results. We also describe Kuperberg's proof for the case of cyclically
symmetric self-complementary plane partitions.

</DOC>
<DOC>
<DOCNO> 10938 </DOCNO>
Defect formation and local gauge invariance


  We propose a new mechanism for formation of topological defects in a U(1)
model with a local gauge symmetry. This mechanism leads to definite
predictions, which are qualitatively different from those of the Kibble-Zurek
mechanism of global theories. We confirm these predictions in numerical
simulations, and they can also be tested in superconductor experiments. We
believe that the mechanism generalizes to more complicated theories.

</DOC>
<DOC>
<DOCNO> 80910 </DOCNO>
Structure and representation theory of double group of four-dimensional


  We generalize the concept of cubic group into any dimension and derive their
conjugate classifications and representation theorys. Double group and spinor
representation are defined. A detailed calculation is carried out on the
structures of four-dimensional cubic group $O_4$ and its double group, as well
as all inequivalent single-valued representations and spinor representations of
$O_4$ . All representations are derived adopting Clifford theory of
decomposition of induced representations.

</DOC>
<DOC>
<DOCNO> 69306 </DOCNO>
The Effective Potential And Additional Large Radius Compactified


  The consequences of large radius extra space-time compactified dimensions on
the four dimensional one loop effective potential are investigated for a model
which includes scalar self interactions and Yukawa coupling to fermions. The
Kaluza-Klein tower of states associated with the extra compact dimensions
shifts the location of the effective potential minimum and modifies its
curvature. The dependence of these effects on the radius of the extra dimension
is illustrated for various choices of coupling constants and masses. For large
radii, the consequence of twisting the fermion boundary condition on the
compactified dimensions is numerically found to produce but a negligible effect
on the effective potential.

</DOC>
<DOC>
<DOCNO> 7938 </DOCNO>
Energy spectra and photoluminescence of charged magneto-excitons


  Charged magneto-excitons X- in a dilute 2D electron gas in narrow and
symmetric quantum wells are studied using exact diagonalization techniques. An
excited triplet X- state with a binding energy of about 1 meV is found. This
state and the singlet are the two optically active states observed in
photoluminescence (PL). The interaction of X-'s with electrons is shown to have
short range, which effectively isolates bound X- states from a dilute e-h
plasma. This results in the insensitivity of PL to the filling factor nu. For
the "dark" triplet X- ground state, the oscillator strength decreases
exponentially as a function of 1/nu which explains why it is not seen in PL.

</DOC>
<DOC>
<DOCNO> 117305 </DOCNO>
Direct measurement of sub-pixel structure of the EPIC MOS CCD on-board


  We have used a mesh experiment in order to measure the sub-pixel structure of
the EPIC MOS CCDs on-board the XMM/NEWTON satellite. The EPIC MOS CCDs have 40
$\mu$m-square pixels which have an open electrode structure in order to improve
the detection efficiency for low-energy X-rays. We obtained restored pixel
images for various X-ray event grades (e.g. split-pixel events, single pixel
events, etc.) at various X-ray energies.
  We confirmed that the open electrode structure results in a distorted
horizontal pixel boundary. The open electrode region generates both single
pixel events and vertically split events, but no horizontally split events.
Because the single pixel events usually show the best energy resolution, we
discuss a method of increasing the fraction of single pixel events from the
open electrode region. Furthermore, we have directly measured the thickness of
the electrodes and dead-layers by comparing spectra from the open electrode
region with those from the other regions: electrodes, electrode finger and
channel stop. We can say that EPIC MOS CCDs are more radiation hard than
front-illumination chips of ACIS on-board Chandra X-ray Observatory because of
their extra absorption thickness above the charge transfer channel. We
calcurated the mean pixel response and found that our estimation has a good
agreement with that of the ground calibration of EPIC MOS CCD.

</DOC>
<DOC>
<DOCNO> 9664 </DOCNO>
Discrete Spectrum in Bose Condensation


  A quantitative description of the whole process of condensation of bosons in
an harmonic trap is given resorting only to Gibbs and Bose postulates, without
assuming equipartition nor continuum statistics. Below Tc discrete spectrum
theory predicts for the thermo-dynamical variables a behavior different from
the continuum case. In particular a new critical temperature is found where the
specific heat exhibits a lambda-like spike. Numerical values of the relevant
quantities depend on the experimental set-up. The theory does not take into
account collective effects in the ground state.

</DOC>
<DOC>
<DOCNO> 13484 </DOCNO>
Quasiparticle dynamics and gap structure in Hg1223 investigated with


  Measurements of the temperature dependence of the quasiparticle (QP) dynamics
in Hg1223 with femtosecond time-resolved optical spectroscopy are reported.
  From the temperature dependence of the amplitude of the photoinduced
reflection, the existence of two gaps is deduced, one temperature dependent Dc
that closes at Tc, and another temperature independent ''pseudogap'' Dp. The
zero-temperature magnitudes of the two gaps are Dc/kTc = 6 +/- 0.5 and Dp/kTc =
6.4 +/- 0.5 respectively. The quasiparticle lifetime is found to exhibit a
divergence as T -> Tc from below, which is attributed to the existence of a
superconducting gap which closes at Tc. Above Tc the relaxation time is longer
than expected for metallic relaxation, which is attributed to the presence of
the ''pseudogap''. The QP relaxation time is found to increase significantly at
low temperatures. This behavior is explained assuming that at low temperatures
the relaxation of photoexcited quasiparticles is governed by a bi-particle
recombination process.

</DOC>
<DOC>
<DOCNO> 150817 </DOCNO>
Anomalous dimensions in N=4 SYM theory at order g^4


  We compute four-point correlation functions of scalar composite operators in
the N=4 supercurrent multiplet at order g^4 using the N=1 superfield formalism.
We confirm the interpretation of short-distance logarithmic behaviours in terms
of anomalous dimensions of unprotected operators exchanged in the intermediate
channels and we determine the two-loop contribution to the anomalous dimension
of the N=4 Konishi supermultiplet.

</DOC>
<DOC>
<DOCNO> 13777 </DOCNO>
Superconducting Gap Structure of Spin-Triplet Superconductor Sr_2RuO_4


  To clarify the superconducting gap structure of the spin-triplet
superconductor Sr_2RuO_4, the in-plane thermal conductivity has been measured
as a function of relative orientations of the thermal flow, the crystal axes,
and a magnetic field rotating within the 2D RuO_2 planes. The in-plane
variation of the thermal conductivity is incompatible with any model with line
nodes vertical to the 2D planes and indicates the existence of horizontal
nodes. These results place strong constraints on models that attempt to explain
the mechanism of the triplet superconductivity.

</DOC>
<DOC>
<DOCNO> 9150 </DOCNO>
Fracture energy of gels


  To clarify effects of crack speed and cross-link density on fracture energy
of acrylamide gels, we evaluated the roughness of the fracture surface and
measured the fracture energy taking into account the roughness. The fracture
energy increases linearly with crack speed $V$ in a fast crack speed region,
and the increasing rate of fracture energy with $V$ decreases with increasing
cross link density in the gels. In a slow crack speed region the fracture
energy depends on crack speed more strongly than in the fast crack speed
region. This indicates that a qualitative change exists in fracture process of
the gels.

</DOC>
<DOC>
<DOCNO> 11238 </DOCNO>
On the approximation of Feynman-Kac path integrals for quantum


  Discretizations of the Feynman-Kac path integral representation of the
quantum mechanical density matrix are investigated. Each infinite-dimensional
path integral is approximated by a Riemann integral over a finite-dimensional
function space, by restricting the integration to a subspace of all admissible
paths. Using this process, a wide class of methods can be derived, with each
method corresponding to a different choice for the approximating subspace. The
traditional ``short-time'' approximation and ``Fourier discretization'' can be
recovered from this approach, using linear and spectral basis functions
respectively. As an illustration, a novel method is formulated using cubic
elements and is shown to have improved convergence properties when applied to a
simple model problem.

</DOC>
<DOC>
<DOCNO> 40238 </DOCNO>
Testing Neutrino Properties at Long Baseline Experiments and Neutrino


  It is shown that explanations of atmospheric neutrino anomaly other than
$\nu_\mu - \nu_\tau oscillations (e.g. decay, decoherence and $\nu_\mu -
\nu_\tau - \nu_{KK}$ mixing) can be tested at future facilities. Stringent
tests of CPT invariance in neutrino oscillations can also be performed.

</DOC>
<DOC>
<DOCNO> 72314 </DOCNO>
Brane Couplings from Bulk Loops


  We compute loop corrections to the effective action of a field theory on a
five-dimensional $S_1/Z_2$ orbifold. We find that the quantum loop effects of
interactions in the bulk produce infinite contributions that require
renormalization by four-dimensional couplings on the orbifold fixed planes.
Thus bulk couplings give rise to renormalization group running of brane
couplings.

</DOC>
<DOC>
<DOCNO> 178930 </DOCNO>
Microscopic systems with and without Coulomb interaction, fragmentation


  We test the influence of the Coulomb interaction on the thermodynamic and
cluster generation properties of a system of classical particles described by
different lattice models. Numerical simulations show that the Coulomb
interaction produces essentially a shift in temperature of quantities like the
specific heat but not qualitative changes. We also consider a cellular model.
The thermodynamic properties of the system are qualitatively unaltered.

</DOC>
<DOC>
<DOCNO> 118231 </DOCNO>
Dynamical effects of a cosmological constant


  The observational evidence for the existence of a non-zero cosmological
constant is getting stronger. It is therefore timely to address the question of
its eventual effect on the dynamics of galaxies, clusters and larger structures
in the Universe. We find, contrary to a recent claim, that the influence of the
cosmological constant has to be negligible for, e.g., the rotation curves of
galaxies. On larger scales, starting with large galaxy clusters, there are
potentially measurable effects from the repulsive addition to the Newtonian
gravitational force caused by the cosmological constant.

</DOC>
<DOC>
<DOCNO> 102053 </DOCNO>
Scalar curvature estimates for compact symmetric spaces


  We establish extremality of Riemannian metrics g with non-negative curvature
operator on symmetric spaces M=G/K of compact type with rk(G)-rk(K)\le 1. Let
g' be another metric with scalar curvature k', such that g'\ge g on 2-vectors.
We show that k'\ge k everywhere on M implies k'=k. Under an additional
condition on the Ricci curvature of g, k'\ge k even implies g'=g. We also study
area-non-increasing spin maps onto such Riemannian manifolds.

</DOC>
<DOC>
<DOCNO> 67671 </DOCNO>
Electroweak physics in six-fermion final states at future e+e- colliders


  Three studies on six-fermion production processes are presented, in which the
production of an intermediate-mass Higgs boson, the top-quark physics and the
analysis of possible anomalous quartic gauge couplings are considered. A Monte
Carlo event generator has been developed for full electroweak tree-level
calculations on six-fermion processes at the Linear Collider. The Monte Carlo
procedure has been adapted to deal with a large variety of diagram topologies,
so as to keep under control the relevant signals and all the backgrounds of
such processes. The effects of initial-state-radiation and beamstrahlung are
also taken into account. The relevance of electroweak backgrounds and
finite-width effects is discussed and several analyses of final-state
distributions are presented, both for the detection of the signals of interest
and for the study of properties of the particles involved, thus showing the
importance of complete calculations for precision studies at the Linear
Collider.

</DOC>
<DOC>
<DOCNO> 152523 </DOCNO>
Tachyon condensation using the disc partition function


  It has been recently proposed that the background independent open
superstring field theory action is given by the disc partition function with
all possible open string operators inserted at the boundary of the disc. We use
this proposal to study tachyon condensation in the D0-D2 system. We evaluate
the disc partition function for the D0-D2 system in presence of a large
Neveu-Schwarz B-field using perturbation theory. This perturbative expansion of
the disc partition function makes sense as the boundary tachyon operator for
the large Neveu-Schwarz B-field is almost marginal. We find that the mass
defect for the formation of the D0-D2 bound state agrees exactly with the
expected result in the large B-field limit.

</DOC>
<DOC>
<DOCNO> 85414 </DOCNO>
Why is the black hole entropy (almost) linear in the horizon area?


  We show that essentially pure classical thermodynamics is sufficient to
determine Bekenstein's formula for the black hole's entropy, $S=\eta A$. We
base our reasoning on the minimal assumption that since black body radiation is
describable by classical thermodynamics, so is the complete black hole-Hawking
radiation system. Furthermore, we argue that any non-linear correction to the
black hole entropy must be quantum mechanical in nature. The proportionality
coefficient, $\eta=1/4\ell_P^2$, must be calculated within a semi-classical or
full-fledged quantum mechanical framework.

</DOC>
<DOC>
<DOCNO> 118374 </DOCNO>
Galactic Globular Clusters as a test for Very Low-Mass stellar models


  We make use of the Next Generation model atmospheres by Allard et al. (1997)
and Hauschildt, Allard & Baron (1999) to compute theoretical models for low and
very low-mass stars for selected metallicities in the range Z= 0.0002 to 0.002.
On this basis, we present theoretical predictions covering the sequence of
H-burning stars as observed in galactic globulars from the faint end of the
Main Sequence up to, and beyond, the cluster Turn Off. The role played by the
new model atmospheres is discussed, showing that present models appear in
excellent agreement with models by Baraffe et al. (1997) as computed on quite
similar physical basis. One finds that the theoretical mass-luminosity
relations based on this updated set of models, are in good agreement with the
empirical data provided by Henry & McCarthy (1993). Comparison with HST
observation discloses that the location in the Color-Magnitude diagram of the
lower Main Sequence in galactic globular clusters appears again in good
agreement with the predicted sensitive dependence of these sequences on the
cluster metallicity.

</DOC>
<DOC>
<DOCNO> 117517 </DOCNO>
Young Massive Star Clusters in Spiral Galaxies. III. Correlations


  We present an analysis of correlations between integrated properties of
galaxies and their populations of young massive star clusters. Data for 21
nearby galaxies presented by Larsen & Richtler (1999) are used together with
literature data for 10 additional galaxies, spanning a range in specific U-band
luminosity T_L(U) from 0 to 15. We find that T_L(U) correlates with several
observable host galaxy parameters, in particular the ratio of Far-Infrared
(FIR) to B-band flux and the optical surface brightness. Taking the FIR
luminosity as an indicator of the star formation rate (SFR), it is found that
T_L(U) correlates very well with the SFR per unit area. A similar correlation
is seen between T_L(U) and the atomic hydrogen surface density. The cluster
formation efficiency seems to depend on the SFR in a continuous way, rather
than being related to any particularly violent mode of star formation. We
discuss fundamental features of possible scenarios for cluster formation. One
possibility is that the correlation between T_L(U) and SFR is due to a common
controlling parameter, most probably the density of the ISM. Another scenario
conceives a high T_L(U) as resulting from the energy input from many massive
stars in case of a high SFR.

</DOC>
<DOC>
<DOCNO> 122472 </DOCNO>
The Helium abundance problem and non-minimally coupled quintessence


  There is a tension between observed Helium abundance and the prediction of
the standard Big Bang Nucleosynthesis. We show that non-minimally quintessence
model may help to reduce this tension between theory and observation.

</DOC>
<DOC>
<DOCNO> 122223 </DOCNO>
High-Resolution spectroscopy of the low-mass X-ray binary EXO 0748-67


  We present initial results from observations of the low-mass X-ray binary EXO
0748-67 with the Reflection Grating Spectrometer on board the XMM-Newton
Observatory. The spectra exhibit discrete structure due to absorption and
emission from ionized neon, oxygen, and nitrogen. We use the quantitative
constraints imposed by the spectral features to develop an empirical model of
the circumsource material. This consists of a thickened accretion disk with
emission and absorption in the plasma orbiting high above the binary plane.
This model presents challenges to current theories of accretion in X-ray binary
systems.

</DOC>
<DOC>
<DOCNO> 99907 </DOCNO>
2-symmetric transformations for 3-manifolds of genus two


  As previously known, all 3-manifolds of genus two can be represented by
edge-coloured graphs uniquely defined by 6-tuples of integers satisfying simple
conditions. The present paper describes an ``elementary transformation'' on
these 6-tuples which changes the associated graph but does not change the
represented manifold. This operation is a useful tool in the classification
problem for 3-manifolds of genus two; in fact, it allows to define an
equivalence relation on ``admissible'' 6-tuples so that equivalent 6-tuples
represent the same manifold. Different equivalence classes can represent the
same manifold; however, equivalence classes ``almost always'' contain
infinitely many 6-tuples. Finally, minimal representatives of the equivalence
classes are described.

</DOC>
<DOC>
<DOCNO> 40466 </DOCNO>
The S-wave \Lambda\pi phase shift is not large


  We study the strong interaction S-wave \Lambda\pi phase shift in the region
of the \Xi mass in the framework of a relativistic chiral unitary approach
based on coupled channels. All parameters have been previously determined in a
fit to strangeness S= -1 S-wave kaon-nucleon data. We find 0^\circ \le \delta_0
\le 1.1^\circ in agreement with previous chiral perturbation theory
calculations (or extensions thereof). We also discuss why a recent coupled
channel K-matrix calculation gives a result for \delta_0 that is negative and
much bigger in magnitude. We argue why that value should not be trusted.

</DOC>
<DOC>
<DOCNO> 117888 </DOCNO>
Evidence for a Young Stellar Population in NGC 5018


  Two absorption line indices, Ca II and Hdelta/FeI4045, measured from high
resolution spectra are used with evolutionary synthesis models to verify the
presence of a young stellar population in NGC 5018. The derived age of this
population is about ~2.8 Gyr with a metallicity roughly solar and it completely
dominates the integrated light of the galaxy near 4000 A.

</DOC>
<DOC>
<DOCNO> 99917 </DOCNO>
Chracterization of Cyclic and Separating Vectors and Application to an


  In this paper we examine an inverse problem in the modular theory of von
Neumann algebras in the case of finite factors. First we give a
characterization of cyclic and separating vectors for finite factors in terms
of operators associated with this vector and being affiliated with the factor.
Further we show how this operator generates the modular objects of the given
cyclic and separating vector generalizing an idea of Kadison and Ringrose. With
the help of these rather technical results we show under an appropriate
condition, which is always fulfilled for finite type I factors, that there
exists another simple class of solutions of the inverse problem beside a
trivial one which always exists. Finally we give a complete classification of
the solutions of the inverse problem in the case of modular operators having
pure point spectrum which is no restriction in the type I case. In a subsequent
paper these results will be generalized to all semifinite factors.

</DOC>
<DOC>
<DOCNO> 151769 </DOCNO>
Conformal Field Theory Correlators From sine-Gordon Model on AdS


  Using the proposed AdS/CFT correspondence, we calculate the correlators of
operators of conformal field theory at the boundary of AdS$_{d+1}$
corresponding to the sine-Gordon model in the bulk.

</DOC>
<DOC>
<DOCNO> 119505 </DOCNO>
NLS1s and Sy1s: A comparison of ionized X-ray absorber properties


  The first results from a systematic study of warm absorbers in NLS1s using
BeppoSAX public archive data are presented here. We confirm ASCA results
showing that a warm absorber, as modeled by two oxygen K-shell absorption
edges, is less frequent in NLS1s than in broad line (BL) Sy1s (about 20 per
cent versus about 50 per cent). However, our study suggests that the ionization
state of NLS1s is not lower than that of BLS1s, as opposed to the ASCA-based
results. The soft excess temperatures of our sample, when fitted with blackbody
emission models, lie within a small range of values (about 0.02-0.15 keV in the
rest frame) with no marked dependence on source luminosity. This is in
agreement with ASCA-based findings for NLS1s and early results from IUE-ROSAT
BL Sy1 observations.

</DOC>
<DOC>
<DOCNO> 69344 </DOCNO>
Low $Q^2$ wave-functions of pions and kaons and their parton


  We study the low $Q^2$ wave-functions of pions and kaons as an expansion in
terms of hadron-like Fock state fluctuations. In this formalism, pion and kaon
wave-functions are related one another. Consequently, the knowledge of the pion
structure allows the determination of parton distributions in kaons. In
addition, we show that the intrinsic (low $Q^2$) sea of pions and kaons are
different due to their different valence quark structure. Finally, we analize
the feasibility of a method to extract kaon's parton distribution functions
within this approach and compare with available experimental data.

</DOC>
<DOC>
<DOCNO> 11587 </DOCNO>
Reply to ``Comment on `Critical behavior of a two-species


  Our recent Monte Carlo results [Phys. Rev. E 61 (2000) 6330] for the
one-dimensional reaction-diffusion process A+B->2B and B->A lead to the
correlation length exponent estimate nu=2.21 +/- 0.05. In a comment on our work
[cond-mat/0007366] the exact value is claimed to be nu=2. We reply that the
arguments advanced in the comment fail to prove the claim.

</DOC>
<DOC>
<DOCNO> 12279 </DOCNO>
Passive Tracer Dynamics in 4 Point-Vortex Flow


  The advection of passive tracers in a system of 4 identical point vortices is
studied when the motion of the vortices is chaotic. The phenomenon of
vortex-pairing has been observed and statistics of the pairing time is
computed. The distribution exhibits a power-law tail with exponent (\sim 3.6),
implying finite average pairing time. Tracer motion is studied for a chosen
initial condition of the vortex system. Accessible phase space is investigated.
The size of the cores around the vortices is well approximated by the minimum
inter-vortex distance and stickiness to these cores is observed. We investigate
the origin of stickiness which we link to the phenomenon of vortex pairing and
jumps of tracers between cores. Motion within the core is considered and
fluctuations are shown to scale with tracer-vortex distance (r) as (r^{6}). No
outward or inward diffusion of tracers are observed. This investigation allows
the separation of the accessible phase space in four distinct regions, each
with its own specific properties: the region within the cores, the reunion of
the periphery of all cores, the region where vortex motion is restricted and
finally the far-field region. We speculate that the stickiness to the cores
induced by vortex-pairings influences the long-time behavior of tracers and
their anomalous diffusion.

</DOC>
<DOC>
<DOCNO> 101658 </DOCNO>
BPS states of curves in Calabi--Yau 3--folds


  The Gopakumar-Vafa conjecture is defined and studied for the local geometry
of a curve in a Calabi-Yau 3-fold. The integrality predicted in Gromov-Witten
theory by the Gopakumar-Vafa BPS count is verified in a natural series of cases
in this local geometry. The method involves Gromov-Witten computations, Mobius
inversion, and a combinatorial analysis of the numbers of etale covers of a
curve.

</DOC>
<DOC>
<DOCNO> 8692 </DOCNO>
Theory of the first-order isostructural valence phase transitions in


  For describing the first-order isostructural valence phase transition in
mixed valence compounds we develop a new approach based on the lattice Anderson
model. We take into account the Coulomb interaction between localized f and
conduction band electrons and two mechanisms of electron-lattice coupling. One
is related to the volume dependence of the hybridization. The other is related
to local deformations produced by f- shell size fluctuations accompanying
valence fluctuations. The large f -state degeneracy allows us to use the 1/N
expansion method. Within the model we develop a mean-field theory for the
first-order valence phase transition in YbInCu_{4}. It is shown that the
Coulomb interaction enhances the exchange interaction between f and conduction
band electron spins and is the driving force of the phase transition. A
comparison between the theoretical calculations and experimental measurements
of the valence change, susceptibility, specific heat, entropy, elastic
constants and volume change in YbInCu_{4} and YbAgCu_{4} are presented, and a
good quantitative agreement is found. On the basis of the model we describe the
evolution from the first-order valence phase transition to the continuous
transition into the heavy-fermion ground state in the series of compounds
YbIn_{1-x}Ag_{x}Cu_{4}. The effect of pressure on physical properties of
YbInCu_{4} is studied and the H-T phase diagram is found.

</DOC>
<DOC>
<DOCNO> 117170 </DOCNO>
PopRatio: A program to calculate atomic level populations in


  We describe a Fortran 90 program to calculate population ratios of atomic
levels. The program solves the equations of statistical equilibrium considering
all possible bound-bound processes: spontaneous, collisional or radiation
induced (the later either directly or by fluorescence). There is no limit on
the number of levels or in the number of processes that may be taken into
account. The program may find a wide range of applicability in astronomical
problems, such as interpreting fine-structure absorption lines or collisionally
excited emission lines (such as coronal emission lines) in the spectra of
several objects, and also in calculating the cooling rates due to collisional
excitation.

</DOC>
<DOC>
<DOCNO> 170446 </DOCNO>
Classical simulation of quantum entanglement without local hidden


  Recent work has extended Bell's theorem by quantifying the amount of
communication required to simulate entangled quantum systems with classical
information. The general scenario is that a bipartite measurement is given from
a set of possibilities and the goal is to find a classical scheme that
reproduces exactly the correlations that arise when an actual quantum system is
measured. Previous results have shown that, using local hidden variables, a
finite amount of communication suffices to simulate the correlations for a Bell
state. We extend this in a number of ways. First, we show that, when the
communication is merely required to be finite {\em on average}, Bell states can
be simulated {\em without} any local hidden variables. More generally, we show
that arbitrary positive operator valued measurements on systems of $n$ Bell
states can be simulated with $O(n 2^n)$ bits of communication on average
(again, without local hidden variables). On the other hand, when the
communication is required to be {\em absolutely bounded}, we show that a finite
number of bits of local hidden variables is insufficent to simulate a Bell
state. This latter result is based on an analysis of the non-deterministic
communication complexity of the NOT-EQUAL function, which is constant in the
quantum model and logarithmic in the classical model.

</DOC>
<DOC>
<DOCNO> 150647 </DOCNO>
Confinement on the Brane


  A non-perturbative confinement mechanism has been proposed to explain the
fate of the unbroken gauge group on the world-volume of annihilating
D-brane-anti-D-brane pairs. In this paper, we examine this phenomenon closely
from several different perspectives. Existence of the confinement mechanism is
most easily seen by noticing that the fundamental string emerges as the
confined electric flux string at the end of the annihilation process. After
reviewing the confinement proposal in general, this is shown explicitly in the
D2-anti-D2 case in the M-theory limit. Finally, we address the crucial issue of
whether and how confinement occurs in the weakly coupled limit of string
theory.

</DOC>
<DOC>
<DOCNO> 116631 </DOCNO>
The exact solution of the Riemann problem with non-zero tangential


  We have generalised the exact solution of the Riemann problem in special
relativistic hydrodynamics for arbitrary tangential flow velocities. The
solution is obtained by solving the jump conditions across shocks plus an
ordinary differential equation arising from the self-similarity condition along
rarefaction waves, in a similar way as in purely normal flow. The dependence of
the solution on the tangential velocities is analysed, and the impact of this
result on the development of multidimensional relativistic hydrodynamic codes
(of Godunov type) is discussed.

</DOC>
<DOC>
<DOCNO> 122792 </DOCNO>
Physical parameters in relativistic jets from Compact Symmetric Objects


  Compact symmetric objects conform a class of sources characterized by high
luminosity radio emission located symmetrically on both sides of the active
galactic nucleus on linear scales of less than 1 kpc. Given their small size,
the hot spots of the jets in CSOs provide a unique laboratory for the study of
the physics of relativistic jets and their environment close to the central
engine.
  We present a simple model for the hot spots in CSOs assuming synchrotron
emission, minimum energy and ram pressure equilibrium with the external medium.
Further comparison of our model with observational data allows us to constrain
the physical parameters in the hot spots and the jets feeding them, and the
density profile of the external medium.

</DOC>
<DOC>
<DOCNO> 39710 </DOCNO>
CP Violation in Hyperon Decays


  The theory and phenomenology of CP violation in hyperon decays is summarized.

</DOC>
<DOC>
<DOCNO> 70217 </DOCNO>
Summary of Golden Measurements at a $\nu$-Factory


  The precision and discovery potential of a neutrino factory based on muon
storage rings is summarized. For three-family neutrino oscillations, we analyze
how to measure or severely constraint the angle $\theta_{13}$, CP violation,
MSW effects and the sign of the atmospheric mass difference $\Delta m^2_{23}$.
The appearance of ``wrong-sign muons'' at three reference baselines is
considered: 732 km, 3500 km and 7332 km. We exploit the dependence of the
signal on the neutrino energy, and include as well realistic background
estimations and detection efficiencies. The optimal baseline turns out to be
$O$(3000 km).

</DOC>
<DOC>
<DOCNO> 121289 </DOCNO>
Cosmic Defects and CMB anisotropy


  Recent measurements of the cosmic microwave background (CMB) anisotropies by
BOOMERANG and MAXIMA collaborations have tightened the observational
constraints on theories of structure formation. They disagree with the
predictions of conventional topological defect models. Considering the fact
that topological defects are predicted by the majority of realistic particle
physics models, the exact nature of the constraints imposed by the recent data
on the population and the properties of the defects must be fully understood.
We show that the predictions of current cosmic string models can be brought
into a closer agreement with the observations by choosing a closed universe
with $\Omega=1.3$ and by including the effects of the small-scale structure and
radiation products of the strings. These alone, however, are not sufficient for
obtaining a good fit to the measured shape of the angular power spectrum. To
fit the data cosmic strings would either have to be correlated on large
(perhaps superhorizon) scales or would have to possess a higher degree of
coherence, i.e. be more ``time-correlated'.

</DOC>
<DOC>
<DOCNO> 8340 </DOCNO>
Spin Dynamics and Orbital State in LaTiO_3


  A neutron scattering study of the Mott-Hubbard insulator LaTiO$_{3}$
(T$_{{\rm N}}=132$ K) reveals a spin wave spectrum that is well described by a
nearest-neighbor superexchange constant $J=15.5$ meV and a small
Dzyaloshinskii-Moriya interaction ($D=1.1$ meV). The nearly isotropic spin wave
spectrum is surprising in view of the absence of a static Jahn-Teller
distortion that could quench the orbital angular momentum, and it may indicate
strong orbital fluctuations. A resonant x-ray scattering study has uncovered no
evidence of orbital order in LaTiO$_{3}$.

</DOC>
<DOC>
<DOCNO> 120778 </DOCNO>
The Pseudo-$C_l$ method: Cosmic microwave background anisotropy power


  As the era of high precision cosmology approaches, the empirically determined
power spectrum of the microwave background anisotropy $C_l$ will provide a
crucial test for cosmological theories. We present an exact semi-analytic
framework for the study of the ampling statistics of the $C_l$ resulting from
observations with partial sky coverage and anisotropic noise distributions.
This includes space-borne, air-borne and ground-based experiments. We apply
this theory to demonstrate its power for constructing fast but unbiased
approximate methods for the joint estimation of cosmological parameters.
Further applications, such as a test for possible non-Gaussianity of the
underlying theory and a ``poor man's power spectrum estimator'' are suggested.
An appendix derives recursion relations for the efficient computation of the
couplings between spherical harmonics on the cut sky.

</DOC>
<DOC>
<DOCNO> 70991 </DOCNO>
Confinement, magnetic Z(N) symmetry and low energy effective theory of


  In these notes I explain the idea how one could understand confinement by
studying the low energy effective dynamics of non Abelian gauge theories. I
argue that under some mild assumptions, the low energy dynamics is determined
universally by the spontaneous breaking of the magnetic symmetry introduced by
't Hooft more than 20 years ago. The degrees of freedom in the effective theory
are magnetic vortices. They play a similar role in confining dynamics to the
role played by pions and sigma in the chiral symmetry breaking dynamics.
 I give explicit derivation of the effective theory in 2+1 dimensional weekly
coupled confining models and give arguments that it remains qualitatively the
same in strongly coupled 2+1 dimensional gluodynamics. Confinement in this
effective theory is a very simple classical statement about long range
interaction between topological solitons, which follows by a simple direct
classical calculation from the structure of the effective Lagrangian. I discuss
the elements of this picture which generalize to 3+1 dimensions and point to
the open questions still remaining.

</DOC>
<DOC>
<DOCNO> 72177 </DOCNO>
B Physics at the Z0 Resonance


  B physics results from e+ e- annihilation at the Z0 resonance are reviewed. A
vast program is summarised, including the study of B+, B0d, B0s and b baryon
lifetimes, the time dependence of B0d and B0s oscillations, the width
difference in the B0s system, and the measurements of the magnitudes of the CKM
matrix elements Vcb and Vub.

</DOC>
<DOC>
<DOCNO> 40201 </DOCNO>
A measurement of the branching fraction of the exclusive decay B^0 -->


  The b --> s gamma transition proceeds by a loop ``penguin'' diagram. It may
be used to measure precisely the couplings of the top quark and to search for
the effects of any new particles appearing in the loop. We present a
preliminary measurement of the branching fraction of the exclusive decay, B^0
--> K^{*0}gamma. We use 8.6 x 10^6 B-anti-B decays to measure B(B^0 -->
K^{*0}gamma) = (5.4+/-0.8+/-0.5) x 10^{-5}.

</DOC>
<DOC>
<DOCNO> 68632 </DOCNO>
Green's Function in Weak Interactions (in Matter) and Impossibility of


  It is shown that the equation for Green's function of fermions (neutrinos)
with weak interactions (in matter) coincides with the equation for Green's
function of fermions in vacuum. This result is a consequence of the fact that
the right components of fermions do not participate in weak interactions. As a
result we come to a conclusion: the mechanism of resonance enhancement of
neutrino oscillations in matter (i.e. MSW effect) cannot exist.

</DOC>
<DOC>
<DOCNO> 122590 </DOCNO>
Optical spectral variability of PG QSOs


  In previous studies we have shown that the optical variability of quasars
increases, on average, with redshift. We explained this dependance in terms of
a hardening of the spectrum during bright phases, coupled with the increase of
the rest-frame frequency for increasing redshift. We re-analize now these
correlations on the basis of new light curves of PG quasars, recently published
by the Wise Observatory group.

</DOC>
<DOC>
<DOCNO> 13749 </DOCNO>
Intermittence and roughening of periodic elastic media


  We analyze intermittence and roughening of an elastic interface or domain
wall pinned in a periodic potential, in the presence of random-bond disorder in
(1+1) and (2+1) dimensions. Though the ensemble average behavior is smooth, the
typical behavior of a large sample is intermittent, and does not self-average
to a smooth behavior. Instead, large fluctuations occur in the mean location of
the interface and the onset of interface roughening is via an extensive
fluctuation which leads to a jump in the roughness of order $\lambda$, the
period of the potential. Analytical arguments based on extreme statistics are
given for the number of the minima of the periodicity visited by the interface
and for the roughening cross-over, which is confirmed by extensive exact ground
state calculations.

</DOC>
<DOC>
<DOCNO> 100743 </DOCNO>
Cohomology of the variational bicomplex on the infinite order jet space


  We obtain the cohomology of the variational bicomplex on the infinite order
jet space of a smooth fiber bundle in the class of exterior forms of finite jet
order. This provides a solution of the global inverse problem of the calculus
of variations of finite order on fiber bundles.

</DOC>
<DOC>
<DOCNO> 13612 </DOCNO>
Proximity Action theory of superconductive nanostructures


  We review a novel approach to the superconductive proximity effect in
disordered normal-superconducting (N-S) structures. The method is based on the
multicharge Keldysh action and is suitable for the treatment of interaction and
fluctuation effects. As an application of the formalism, we study the subgap
conductance and noise in two-dimensional N-S systems in the presence of the
electron-electron interaction in the Cooper channel. It is shown that singular
nature of the interaction correction at large scales leads to a nonmonotonuos
temperature, voltage and magnetic field dependence of the Andreev conductance.

</DOC>
<DOC>
<DOCNO> 71283 </DOCNO>
Quark confinement in the analytic approach to QCD


  The interquark potential is constructed by making use of the new analytic
running coupling in QCD. This running coupling arises under ``analytization''
of the renormalization group equation. The rising behavior of the interquark
potential at large distances, which provides the quark confinement, is shown
explicitly. The estimation of the parameter $\Lambda_{QCD}$ is obtained.

</DOC>
<DOC>
<DOCNO> 83503 </DOCNO>
Well-Typed Logic Programs Are not Wrong


  We consider prescriptive type systems for logic programs (as in Goedel or
Mercury). In such systems, the typing is static, but it guarantees an
operational property: if a program is "well-typed", then all derivations
starting in a "well-typed" query are again "well-typed". This property has been
called subject reduction. We show that this property can also be phrased as a
property of the proof-theoretic semantics of logic programs, thus abstracting
from the usual operational (top-down) semantics. This proof-theoretic view
leads us to questioning a condition which is usually considered necessary for
subject reduction, namely the head condition. It states that the head of each
clause must have a type which is a variant (and not a proper instance) of the
declared type. We provide a more general condition, thus reestablishing a
certain symmetry between heads and body atoms. The condition ensures that in a
derivation, the types of two unified terms are themselves unifiable. We discuss
possible implications of this result. We also discuss the relationship between
the head condition and polymorphic recursion, a concept known in functional
programming.

</DOC>
<DOC>
<DOCNO> 83360 </DOCNO>
Exploiting auxiliary distributions in stochastic unification-based


  This paper describes a method for estimating conditional probability
distributions over the parses of ``unification-based'' grammars which can
utilize auxiliary distributions that are estimated by other means. We show how
this can be used to incorporate information about lexical selectional
preferences gathered from other sources into Stochastic ``Unification-based''
Grammars (SUBGs). While we apply this estimator to a Stochastic
Lexical-Functional Grammar, the method is general, and should be applicable to
stochastic versions of HPSGs, categorial grammars and transformational
grammars.

</DOC>
<DOC>
<DOCNO> 120270 </DOCNO>
Order and Chaos in the Local Disc Stellar Kinematics


  The effects of the Galactic bar on the velocity distribution of old disc
stars in the Solar neighbourhood are investigated using high-resolution 2D test
particle simulations. A detailed orbital analysis reveals that the structure of
the U-V distribution in these simulations is closely related to the phase-space
extent of regular and chaotic orbits. At low angular momentum and for a
sufficiently strong bar, stars mainly follow chaotic orbits which may cross the
corotation radius and the U-V contours follow lines of constant Jacobi's
integral except near the regions occupied by weakly populated eccentric regular
orbits. These properties can naturally account for the observed outward motion
of the local high asymmetric drift stars.

</DOC>
<DOC>
<DOCNO> 152229 </DOCNO>
Alternative Formulation of The Quantum Electroweak Theory


  The quantization of the electroweak theory is performed starting from the
Lagrangian given in the so-called unitary gauge in which the unphysical
Goldstone fields disappear. In such a Lagrangian, the unphysical longitudinal
components of the gauge fields are naturally eliminated by introducing the
Lorentz gauge condition. In this way, the quautum theory given in $\alpha
$-gauge is perfectly established by the Faddeev-Popov approach in the framework
of SU(2)$\times $U(1) gauge symmetry. The theory established is not only
simpler than the ordinary R$_\alpha -$gauge theory, but also explicitly
renormalizable. The unitarity of the theory is ensured by the limiting
procedure of letting the gauge parameter $\alpha $ appearing in the massive
vector boson propagators tend to infinity in the final step of calculations.
The formulations of the theory with and without involving the Higgs boson are
discussed separately.

</DOC>
<DOC>
<DOCNO> 178846 </DOCNO>
Flow and the equation of state of nuclear matter


  The status of flow in heavy-ion collisions and of inference of
hadronic-matter properties is reviewed.

</DOC>
<DOC>
<DOCNO> 40078 </DOCNO>
Possible consequences of introduction of the discrete carrier of


  In this work some probable consequences of introduction of discrete medium -
carrier for fields of a substance are considered. The given medium is thinked
as a set of harmonic oscillators filling all space. Discrete medium is
introduced on an image and similarity of a crystalline lattice of a condensed
matter. The particles - excitation are concentrated in space of a "reciprocal
lattice " of discrete medium. This leads to the violation of the energy and
momentum conservation laws at the wave number of particles higher then the wave
number of the reciprocal lattice. Some possible confirmation of the given
consideration may be the behavior of cosmic rays at high energy. The other
possible consequences of the proposed approach in physics of elementary
particles, cosmology, and quantum mechanics are also discussed.

</DOC>
<DOC>
<DOCNO> 83332 </DOCNO>
Boolean Satisfiability with Transitivity Constraints


  We consider a variant of the Boolean satisfiability problem where a subset E
of the propositional variables appearing in formula Fsat encode a symmetric,
transitive, binary relation over N elements. Each of these relational
variables, e[i,j], for 1 <= i < j <= N, expresses whether or not the relation
holds between elements i and j. The task is to either find a satisfying
assignment to Fsat that also satisfies all transitivity constraints over the
relational variables (e.g., e[1,2] & e[2,3] ==> e[1,3]), or to prove that no
such assignment exists. Solving this satisfiability problem is the final and
most difficult step in our decision procedure for a logic of equality with
uninterpreted functions. This procedure forms the core of our tool for
verifying pipelined microprocessors.
  To use a conventional Boolean satisfiability checker, we augment the set of
clauses expressing Fsat with clauses expressing the transitivity constraints.
We consider methods to reduce the number of such clauses based on the sparse
structure of the relational variables.
  To use Ordered Binary Decision Diagrams (OBDDs), we show that for some sets
E, the OBDD representation of the transitivity constraints has exponential size
for all possible variable orderings. By considering only those relational
variables that occur in the OBDD representation of Fsat, our experiments show
that we can readily construct an OBDD representation of the relevant
transitivity constraints and thus solve the constrained satisfiability problem.

</DOC>
<DOC>
<DOCNO> 99592 </DOCNO>
Ermakov-Lewis dynamic invariants with some applications


  Contents: Introduction(3).The method of Ermakov(4).The method of Milne(7).
Pinney's result(8).Lewis' results(8). The interpretation of Eliezer and
Gray(14). The connection of the Ermakov invariant with N\"other's theorem(17).
Possible generalizations of Ermakov's method(20). Geometrical angles and phases
in Ermakov's problem(22). Application to the minisuperspace cosmology(26).
Application to physical optics(42).Conclusions(47). Appendix A: Calculation of
the integral of I(48). Appendix B: Calculation of <\hat{H}> in eigenstates of
\hat{I}(49).References(50).

</DOC>
<DOC>
<DOCNO> 120343 </DOCNO>
The X-Ray Jet of PKS 0637-752: Inverse Compton Radiation from the Cosmic


  We propose that the X-ray emission detected by Chandra from the
100-kiloparsec-scale jet of PKS 0637-752 is produced through inverse Compton
scattering of the Cosmic Microwave Background (CMB). We analyze the physical
state of the jet and show that inverse Compton scattering from the CMB is
consistent with equipartition for a moderate beaming of the emission, with
Doppler factor delta~10. The power transported by the jet is then similar to
that of other powerful blazars, Lj~10^{48} erg/s and the jet has low radiative
efficiency. The radiative cooling times of the electrons are a few thousand
years, compatible with the size of the knot. The low-energy cutoff of the
electron distribution is constrained to be gamma_min~10, the first such
constraint from spectral considerations. A parallel analysis for the SSC model
yields far less reasonable physical conditions.

</DOC>
<DOC>
<DOCNO> 118514 </DOCNO>
Accretion Disks


  In this lecture the basic theory of accretion disks is introduced, with
emphasis on aspects relevant for X-ray binaries and Cataclysmic Variables.

</DOC>
<DOC>
<DOCNO> 13747 </DOCNO>
Streched exponential in non-linear stochastic filed theories


  We consider the time dependent two point function, <\phi_q (t) \phi_-q (0)>
in non-linear stochastic field theories, for which the KPZ equation serves as a
prototype. In particular we consider the small q's and long times such that
\omega_q t>>1 (\omega_q being the corresponding decay rate). We find that,
since the generic case has \omega_q \propto q^\mu for small q where \mu>1, the
decay of the two point function is given by a streched exponential in \omega_qt
multiplied by a factor of t, <\phi_q (t) \phi_-q (0)> \propto
t^{\beta_d}exp[-\gamma(\omega_qt)^{1/\mu}], where \beta_d=(d-1)/2\mu, d is the
dimensionality of space and \gamma a dimensionless constant.

</DOC>
<DOC>
<DOCNO> 85386 </DOCNO>
Energy Release During Disk Accretion onto a Rapidly Rotating Neutron


  The energy release L_s on the surface of a neutron star (NS) with a weak
magnetic field and the energy release L_d in the surrounding accretion disk
depend on two independent parameters that determine its state (for example,
mass M and cyclic rotation frequency f) and is proportional to the accretion
rate. We derive simple approximation formulas illustrating the dependence of
the efficiency of energy release in an extended disk and in a boundary layer
near the NS surface on the frequency and sense of rotation for various NS
equations of state. Such formulas are obtained for the quadrupole moment of a
NS, for a gap between its surface and a marginally stable orbit, for the
rotation frequency in an equatorial Keplerian orbit and in the marginally
stable circular orbit, and for the rate of NS spinup via disk accretion. In the
case of NS and disk counterrotation, the energy release during accretion can
reach $0.67\dot{M}c^2$. The sense of NS rotation is a factor that strongly
affects the observed ratio of nuclear energy release during bursts to
gravitational energy release between bursts in X-ray bursters. The possible
existence of binary systems with NS and disk counterrotation in the Galaxy is
discussed. Based on the static criterion for stability, we present a method of
constructing the dependence of gravitational mass M on Kerr rotation parameter
j and on total baryon mass (rest mass) m for a rigidly rotating neutron star.
We show that all global NS characteristics can be expressed in terms of the
function M(j, m) and its derivatives.

</DOC>
<DOC>
<DOCNO> 40449 </DOCNO>
QED Corrections to Neutrino Electron Scattering


  We evaluate the O(alpha) QED corrections to the recoil electron energy
spectrum in the process nu_l + e --> nu_l + e (+gamma), where (+gamma)
indicates the possible emission of a photon and l=e, mu or tau. The soft and
hard bremsstrahlung differential cross sections are computed for an arbitrary
value of the photon energy threshold. We also study the O(alpha) QED
corrections to the differential cross section with respect to the total
combined energy of the recoil electron and a possible accompanying photon.
Their difference from the corrections to the electron spectrum is investigated.
We discuss the relevance and applicability of both radiative corrections,
emphasizing their role in the analysis of precise solar neutrino electron
scattering experiments.

</DOC>
<DOC>
<DOCNO> 71981 </DOCNO>
Energy Spectra of Reactor Neutrinos at KamLAND


  The upcoming reactor neutrino experiment, KamLAND, has the ability to explore
the Large Mixing Angle (LMA) solution to the solar neutrino problem. Here, we
investigate the precision to which KamLAND should be able to measure these
parameters, utilizing the distortion of the energy spectrum of reactor
neutrinos. Incomplete knowledge of the fuel composition of the reactors will
lead to some error on this measurement. We estimate the size of this effect.

</DOC>
<DOC>
<DOCNO> 72297 </DOCNO>
The scaling evolution of cosmological constant


  In quantum field theory the parameters of the vacuum action are subject to
renormalization group running. In particular, the ``cosmological constant'' is
not a constant in a quantum field theory context, still less should be zero. In
this paper we continue with previous work, and derive the particle
contributions to the running of the cosmological and gravitational constants in
the framework of the Standard Model in curved space-time. At higher energies
the calculation is performed in a sharp cut off approximation. We assess, in
two different frameworks, whether the scaling dependences of the cosmological
and gravitational constants spoil primordial nucleosynthesis. Finally, the
cosmological implications of the running of the cosmological constant are
discussed.

</DOC>
<DOC>
<DOCNO> 39625 </DOCNO>
Neutrino Mass and Oscillations


  Current evidence for neutrino oscillation is reviewed, some areas for closer
investigation are suggested, and a plausible future experimental program is
summarized.

</DOC>
<DOC>
<DOCNO> 40487 </DOCNO>
Search for R-Parity Violating Decays of Supersymmetric Particles in e+e-


  Searches for the production of supersymmetric particles under the assumption
that R-parity is violated via a single dominant LLE, LQD or UDD coupling were
performed. These use the data collected by the ALEPH detector at LEP at
centre-of-mass energies from 188.6 to 201.6 GeV. The numbers of candidate
events observed in the data are consistent with Standard Model expectations.
Upper limits on the production cross sections and lower limits on the masses of
charginos, sleptons, squarks and sneutrinos are derived.

</DOC>
<DOC>
<DOCNO> 69090 </DOCNO>
Antiprotons Annihilation in the Galaxy As A Source of Diffuse Gamma


  The existence of antimatter domains in baryon asymmetrical Universe can
appear as the cosmological consequence of particle theory in inflationary
models with non-homogeneous baryosynthesis. Such a domain can survive in the
early Universe and form globular cluster of antimatter stars in our Galaxy. The
model of antimatter pollution of Galaxy and annihilation with matter gas is
developed. The proton-antiproton annihilation gamma flux is shown to reproduce
the observed galactic gamma background measured by EGRET. From comparison with
observational data the estimation on the maximally allowed amount of antimatter
stars, possibly present in our Galaxy, is found.

</DOC>
<DOC>
<DOCNO> 116272 </DOCNO>
Cooling of Particle Beams in Storage Rings


  Cooling methods are discussed in reference to the electron-positron, ion and
muon beams.

</DOC>
<DOC>
<DOCNO> 117741 </DOCNO>
A GRB Tool Shed


  We describe the design of a suite of software tools to allow users to query
Gamma-Ray Burst (GRB) data and perform data mining expeditions. We call this
suite of tools a shed (SHell for Expeditions using Datamining). Our schedule is
to have a completed prototype (funded via the NASA AISRP) by February, 2002.
Meanwhile, interested users will find a partially functioning tool shed at
http://grb.mankato.msus.edu.

</DOC>
<DOC>
<DOCNO> 118411 </DOCNO>
How flat is the Universe?


  In order to answer this question, we combine ten independent astrophysical
constraints in the space of the density parameters $\Omega_m$ of gravitating
matter and $\Omega_{\Lambda}$ of vacuum energy. We find that $\Omega_m=0.31\pm
0.07$, $\Omega_{\Lambda}=0.63\pm 0.21$, and thus $\Omega_m +
\Omega_{\Lambda}=0.94\pm 0.22$. The total $\chi^2$ is 4.1 for 8 degrees of
freedom, testifying that the various systematic errors included are generous.
We also determine $\Omega_m$ in the exactly flat case. Five supplementary
flat-case constraints can then be included in our fit, with the result
$\Omega_m=1-\Omega_{\Lambda}= 0.337\pm0.031$. It follows that the age of the
Universe is $t_0 = 13.5\pm 1.3$ (0.68/h) Gyr.

</DOC>
<DOC>
<DOCNO> 178925 </DOCNO>
Isospin effects on squeeze-out flow in heavy-ion collisions


  The squeeze-out flow in reactions of $^{124}$Sn + $^{124}$Sn and $^{124}$Ba +
$^{124}$Ba at different incident energies for different impact parameters is
investigated by means of an isospin-dependent quantum molecular dynamics model.
For the first time, it is found that the more neutron-rich system ($% ^{124}$Sn
+ $^{124}$Sn) exhibits weaker squeeze-out flow. This isospin dependence of the
squeeze-out flow is shown to mainly result from the isospin dependence of
nucleon-nucleon cross section and the symmetry energy.

</DOC>
<DOC>
<DOCNO> 72206 </DOCNO>
Determination of polarized parton distribution functions


  We study parametrization of polarized parton distribution functions in the
\alpha_s leading order (LO) and in the next-to-leading order (NLO). From \chi^2
fitting to the experimental data on A_1, optimum polarized distribution
functions are determined. The quark spin content \Delta\Sigma is very sensitive
to the small-x behavior of antiquark distributions which suggests that small-x
data are needed for precise determination of \Delta\Sigma. We propose three
sets of distributions and also provide FORTRAN library for our distributions.

</DOC>
<DOC>
<DOCNO> 118525 </DOCNO>
The Morphologies of the Small Magellanic Cloud


  We compare the distribution of stars of different spectral types, and hence
mean age, within the central SMC and find that the asymmetric structures are
almost exclusively composed of young main sequence stars. Because of the
relative lack of older stars in these features, and the extremely regular
distribution of red giant and clump stars in the SMC central body, we conclude
that tides alone are not responsible for the irregular appearance of the
central SMC. The dominant physical mechanism in determining the current-day
appearance of the SMC must be star formation triggered by a hydrodynamic
interaction between gaseous components. These results extend the results of
population studies (cf. Gardiner and Hatzidimitriou) inward in radius and also
confirm the suggestion of the spheroidal nature of the central SMC based on
kinematic arguments (Dopita et al; Hardy, Suntzeff & Azzopardi). Finally, we
find no evidence in the underlying older stellar population for a ``bar'' or
``outer arm'', again supporting our classification of the central SMC as a
spheroidal body with highly irregular recent star formation.

</DOC>
<DOC>
<DOCNO> 150455 </DOCNO>
Geometry of Orientifolds with NS-NS B-flux


  We discuss geometry underlying orientifolds with non-trivial NS-NS B-flux. If
D-branes wrap a torus with B-flux the rank of the gauge group is reduced due to
non-commuting Wilson lines whose presence is implied by the B-flux. In the case
of D-branes transverse to a torus with B-flux the rank reduction is due to a
smaller number of D-branes required by tadpole cancellation conditions in the
presence of B-flux as some of the orientifold planes now have the opposite
orientifold projection. We point out that T-duality in the presence of B-flux
is more subtle than in the case with trivial B-flux, and it is precisely
consistent with the qualitative difference between the aforementioned two
setups. In the case where both types of branes are present, the states in the
mixed (e.g., 59) open string sectors come with a non-trivial multiplicity,
which we relate to a discrete gauge symmetry due to non-zero B-flux, and
construct vertex operators for the the mixed sector states. Using these results
we revisit K3 orientifolds with B-flux (where K3 is a T^4/Z_M orbifold) and
point out various subtleties arising in some of these models. For instance, in
the Z_2 case the conformal field theory orbifold does not appear to be the
consistent background for the corresponding orientifolds with B-flux. This is
related to the fact that non-zero B-flux requires the presence of both O5^- as
well as O5^+ planes at various Z_2 orbifold fixed points, which appears to be
inconsistent with the presence of the twisted B-flux in the conformal field
theory orbifold. We also consider four dimensional N=2 and N=1 supersymmetric
orientifolds. We construct consistent four dimensional models with B-flux which
do not suffer from difficulties encountered in the K3 cases.

</DOC>
<DOC>
<DOCNO> 101344 </DOCNO>
On the Calculation of Group Characters


  In its most schematic form, the Weyl character formula can be expressed by
the ratio ${P \over Q}$ of two multinomials $P \equiv a(1) + a(2) ... a(D)$ and
$Q \equiv b(1) + b(2) ... b(D)$ where D is the order of Weyl group $W(G_r)$ for
a Lie algebra $G_r$ of rank r. Each and every one of $a(k)$'s and $b(k)$'s is
obtained by the action of a Weyl reflection, i.e. an element of $W(G_r)$. We,
instead, show that there is a way to obtain all these terms without refering to
Weyl reflections. For this, the following observation seems to be crucial: It
is known that there is a set of r weight vectors $\lambda_i, (i=1,2, ... r)$ of
which their scalar products form the inverse Cartan matrix of $G_r$. These are
sometimes called {\bf fundamental dominant weights} of $G_r$. The observation
is now that there are some other sets of r weights which satisfy this same
condition so their number is just equal to order of Weyl group $W(G_r)$. By
specifying these sets of weights completely, we will show that the character of
an irreducible representation can be calculated without any reference to Weyl
group summations. All these and some useful technical points will be given in
detail in the instructive example of $G_2$ Lie algebra.

</DOC>
<DOC>
<DOCNO> 152562 </DOCNO>
Current Algebra Associated with Logarithmic Conformal Field Theories


  We propose a general frame work for deriving the OPEs within a logarithmic
conformal field theory (LCFT). This naturally leads to the emergence of a
logarithmic partner of the energy momentum tensor within an LCFT, and implies
that the current algebra associated with an LCFT is expanded. We derive this
algebra for a generic LCFT and discuss some of its implications. We observe
that two constants arise in the OPE of the energy-momentum tensor with itself.
One of these is the usual central charge.

</DOC>
<DOC>
<DOCNO> 99339 </DOCNO>
The kernel of Fock representations of Wick algebras with braided


  It is shown that the kernel of the Fock representation of a certain Wick
algebra with braided operator of coefficients T, || T ||<= 1, coincides with
the largest quadratic Wick ideal. Improved conditions on the operator T for the
Fock inner product to be strictly positive are given.

</DOC>
<DOC>
<DOCNO> 117749 </DOCNO>
Hydrodynamic Simulations of the Bardeen-Petterson Effect


  We present SPH simulations of accretion discs in orbit about rotating compact
objects such as black holes and neutron stars, and study the structure of
warped discs produced by the Bardeen-Petterson effect. We calculate the
transition radius out to which the disc specific angular momentum vector is
aligned with that of the black hole. We focus on the parameter regime where the
warp dynamics are controlled by bending wave propagation, but also consider
models in which warps are subject to diffusion rather than wave transport, and
are able to consider the fully nonlinear regime. Because of hydrodynamic or
pressure effects, for the parameter range investigated, the transition radius
is always found to be much smaller than that obtained by Bardeen & Petterson
(1975). For discs with midplane Mach numbers of about 10, the transition occurs
between 10 - 16 gravitational radii, whereas for a Mach number of about 30 it
occurs at around 30 gravitational radii. A thicker disc with a Mach number of 5
is found to produce no discernible warped structure. The rate of black hole -
disc alignment is found to be consistent with the ideas of Ress (1978), with
the alignment torque behaving as if it arises from the accreted material
transferring its misaligned component of angular momentum at the larger
transition radius of Bardeen & Petterson (1975). The inclusion of Einstein
precession in the calculations modified both the warped disc structure and,
consistent with linear analysis, produced an increased alignment rate by up to
a factor of 4 because of the effect that a non Keplerian potential has on the
propagation of warps.

</DOC>
<DOC>
<DOCNO> 69705 </DOCNO>
On the origin of current quark mass within nonperturbative QCD


  We develop the theory of fermion induced phononlike excitations of the
instanton liquid. It suggests a mechanism of current quark mass generation
which is easily understandable by calculating the corresponding functional
integral in the tadpole approximation. We systematically study the quark
condensate excitations influenced by the phononlike modes and rederive the
relation Gell-Mann-Oakes-Renner with realistic pion mass. The picture of
$\sigma$-meson as being mixed with the soft scalar glueball-like excitation is
discussed.

</DOC>
<DOC>
<DOCNO> 122020 </DOCNO>
Cygnus X-3 with ISO: investigating the wind


  We observed the energetic binary Cygnus X-3 in both quiescent and flaring
states between 4 and 16 microns using the ISO satellite. We find that the
quiescent source shows the thermal free-free spectrum typical of a hot, fast
stellar wind, such as from a massive helium star. The quiescent mass-loss rate
due to a spherically symmetric, non-accelerating wind is found to be in the
range 0.4-2.9 x 10E-4 solar masses per year, consistent with other infrared and
radio observations, but considerably larger than the 10E-5 solar masses per
year deduced from both the orbital change and the X-ray column density. There
is rapid, large amplitude flaring at 4.5 and 11.5 microns at the same time as
enhanced radio and X-ray activity, with the infrared spectrum apparently
becoming flatter in the flaring state. We believe non-thermal processes are
operating, perhaps along with enhanced thermal emission.

</DOC>
<DOC>
<DOCNO> 84286 </DOCNO>
Quantum Perturbative Approach to Discrete Redshift


  On the largest scales there is evidence of discrete structure, examples of
this are superclusters and voids and also by redshift taking discrete values.
In this paper it is proposed that discrete redshift can be explained by using
the spherical harmonic integer l; this occurs both in the metric or density
perturbations and also in the solution of wave equations in Robertson-Walker
spacetime. It is argued that the near conservation of energy implies that l
varies regularly for wave equations in Robertson-Walker spacetime, whereas for
density perturbations l cannot vary regularly. Once this is assumed then
perhaps the observed value of discrete redshift provides the only observational
or experimental data that directly requires an explanation using both
gravitational and quantum theory. In principle a model using this data could
predict the scale factor R (or equivalently the deceleration parameter q).
Solutions of the Klein-Gordon equation in Robertson-Walker spacetimes are used
to devise models which have redshift taking discrete values, but they predict a
microscopic value for R. A model in which the stress of the Klein-Gordon
equation induces a metrical perturbation of Robertson-Walker spacetime is
devised. Calculations based upon this model predict that the Universe is closed
with $2q_0-1=10^{-4}$.

</DOC>
<DOC>
<DOCNO> 12153 </DOCNO>
Electric field induced strong localization of electrons on solid


  Two-dimensional electron system on the liquid helium surface is one of the
leading candidates for constructing large analog quantum computers (P.M.
Platzman and M.I. Dykman, Science 284, 1967 (1999)). Similar electron systems
on the surfaces of solid hydrogen or solid neon may have some important
advantages with respect to electrons on liquid helium in quantum computing
applications, such as larger state separation $\Delta E$, absence of
propagating capillary waves (or ripplons), smaller vapor pressure, etc. As a
result, it may operate at higher temperatures. Surface roughness is the main
hurdle to overcome in building a realistic quantum computer using these states.
Electric field induced strong localization of surface electrons is shown to be
a convenient tool to characterize surface roughness.

</DOC>
<DOC>
<DOCNO> 119819 </DOCNO>
Simultaneous radio and X-ray observations of Galactic Centre low mass


  We have performed simultaneous X-ray and radio observations of thirteen
Galactic centre low-mass X-ray binaries in 1998 April using the Wide-Field
Cameras onboard BeppoSAX and the Australia Telescope Compact Array, the latter
simultaneously at 4.8 and 8.64 GHz. We detect two Z sources, GX 17+2 and GX
5-1, and the unusual `hybrid' source GX 13+1. Upper limits, which are
significantly deeper than previous non-detections, are placed on the radio
emission from two more Z sources and seven atoll sources. Hardness-Intensity
diagrams constructed from the Wide-Field Camera data reveal GX 17+2 and GX 5-1
to have been on the lower part of the horizontal branch and/or the upper part
of the normal branch, at the time of the observations, and the two non-detected
Z sources, GX 340+0 and GX 349+2, to have been on the lower part of the normal
branch. This is consistent with the previous empirically-determined relation
between radio and X-ray emission from Z sources, in which radio emission is
strongest on the Horizontal branch and weakest on the Flaring branch. For the
first time we have information on the X-ray state of atoll sources, which are
clearly radio-quiet relative to the Z sources, during periods of observed radio
upper limits. We place limits on the linear polarisation from the three
detected sources, and use accurate radio astrometry of GX 17+2 to confirm that
it is probably not associated with the optical star NP Ser. Additionally we
place strong upper limits on the radio emission from the X-ray binary 2S
0921-630, disagreeing with suggestions that it is a Z-source viewed edge-on.

</DOC>
<DOC>
<DOCNO> 102545 </DOCNO>
Extremal Approximately Convex Functions and the Best Constants in a


  Let $n\ge1$ and $B\ge2$. A real-valued function $f$ defined on the
$n$-simplex $\Delta_n$ is approximately convex with respect to $\Delta_{B-1}$
iff f(\sum_{i=1}^B t_ix_i) \le \sum_{i=1}^B t_if(x_i) +1 for all $x_1,...,x_B
\in \Delta_n$ and all $(t_1,...,t_B)\in \Delta_{B-1}$. We determine explicitly
the extremal (i.e. pointwise largest) function of this type which vanishes on
the vertices of $\Delta_n$. We also prove a stability theorem of Hyers-Ulam
type which yields as a special case the best constants in the Hyers-Ulam
stability theorem for $\epsilon$-convex functions.

</DOC>
<DOC>
<DOCNO> 83048 </DOCNO>
A Logic for SDSI's Linked Local Name Spaces


  Abadi has introduced a logic to explicate the meaning of local names in SDSI,
the Simple Distributed Security Infrastructure proposed by Rivest and Lampson.
Abadi's logic does not correspond precisely to SDSI, however; it draws
conclusions about local names that do not follow from SDSI's name resolution
algorithm. Moreover, its semantics is somewhat unintuitive. This paper presents
the Logic of Local Name Containment, which does not suffer from these
deficiencies. It has a clear semantics and provides a tight characterization of
SDSI name resolution. The semantics is shown to be closely related to that of
logic programs, leading to an approach to the efficient implementation of
queries concerning local names. A complete axiomatization of the logic is also
provided.

</DOC>
<DOC>
<DOCNO> 150636 </DOCNO>
Tachyon Condensation in Superstring Field Theory


  It has been conjectured that at the stationary point of the tachyon potential
for the D-brane-anti-D-brane pair or for the non-BPS D-brane of superstring
theories, the negative energy density cancels the brane tensions. We study this
conjecture using a Wess-Zumino-Witten-like open superstring field theory free
of contact term divergences and recently shown to give 60% of the vacuum energy
by condensation of the tachyon field alone. While the action is non-polynomial,
the multiscalar tachyon potential to any fixed level involves only a finite
number of interactions. We compute this potential to level three, obtaining 85%
of the expected vacuum energy, a result consistent with convergence that can
also be viewed as a successful test of the string field theory. The resulting
effective tachyon potential is bounded below and has two degenerate global
minima. We calculate the energy density of the kink solution interpolating
between these minima finding good agreement with the tension of the D-brane of
one lower dimension.

</DOC>
<DOC>
<DOCNO> 121418 </DOCNO>
An Off-line Scan of the BATSE Daily Records and a Large Uniform Sample


  During a scan of the archival BATSE daily records covering the entire 9.1
years (TJD 8369-11690) of the BATSE operation, 3906 gamma-ray bursts (GRBs)
have been detected. 2068 of these GRBs are previously known BATSE triggers
while 1838 of them are new non-triggered bursts. It is important that all
events were detected in the same type of data and were processed with the same
procedure. Therefore these 3906 GRBs constitute a uniform sample. We have
created a publically available electronic data base containing this sample. We
describe the procedures of the data reduction, the selection of the GRB
candidates, and the statistical tests for possible non-GRB contaminations. We
also describe a novel test burst method used to measure the scan efficiency and
the information obtained using the test bursts. Our scan decreases the BATSE
detection threshold to ~0.1 photons/sec/cm2. As a first result, we show that
the differential log N - log P distribution corrected for the detection
efficiency extends to low brightnesses without any indication of a turn-over.
Any reasonable extrapolation of the new log N - log P to lower brightnesses
imply a rate of several thousands of GRBs in the Universe per year.

</DOC>
<DOC>
<DOCNO> 68681 </DOCNO>
Measuring gamma cleanly with CP-tagged Bs and Bd decays


  We propose a new method for measuring the CKM phase gamma using the partial
rates for CP-tagged Bs decays. Such an experiment could be performed at a very
high luminosity symmetric e+e- collider operating at the Upsilon(5S) resonance,
where the Bs-Bsbar state is produced in a state of definite CP. We also discuss
CP-tagging in the Bd system at the Upsilon(4S), where a time-dependent analysis
is required to compensate for the anticipated large CP violation in Bd-Bdbar
mixing.

</DOC>
<DOC>
<DOCNO> 84602 </DOCNO>
Existence of Noncompact Static Spherically Symmetric Solutions of


  We consider static spherically symmetric solutions of Einstein's equations
coupled to an SU(2) Yang Mills field that are smooth at the center of spherical
symmetry. We prove that with small cosmological constant there exist solutions
that possess a coordinate singularity at some r that is not maximum. The
singularity can be removed with a Kruskal-like change of coordinates.

</DOC>
<DOC>
<DOCNO> 102271 </DOCNO>
On the Deligne-Simpson problem


  The Deligne-Simpson problem is formulated like this: give necessary and
sufficient conditions for the choice of the conjugacy classes $C_j\subset
SL(n,{\bf C})$ or $c_j\subset sl(n,{\bf C})$ so that there exist irreducible
$(p+1)$-tuples of matrices $M_j\in C_j$ or $A_j\in c_j$ satisfying the equality
$M_1... M_{p+1}=I$ or $A_1+... +A_{p+1}=0$. We solve the problem for generic
eigenvalues with the exception of the case of matrices $M_j$ when the greatest
common divisor of the numbers $\Sigma_{j,l}(\sigma)$ of Jordan blocks of a
given matrix $M_j$, with a given eigenvalue $\sigma$ and of a given size $l$
(taken over all $j$, $\sigma$, $l$) is $>1$. Generic eigenvalues are defined by
explicit algebraic inequalities. For such eigenvalues there exist no reducible
$(p+1)$-tuples. The matrices $M_j$ and $A_j$ are interpreted as monodromy
operators of regular linear systems and as matrices-residua of fuchsian ones on
Riemann's sphere.

</DOC>
<DOC>
<DOCNO> 68248 </DOCNO>
Exact O(g^2 alpha_s) top decay width from general massive two-loop


  We calculate the b-dependent self-energy of the top quark at O(g^2 \alpha_s)
by using a general massive two-loop algorithm proposed in a previous article.
  From this we derive by unitarity the O(\alpha_s) radiative corrections to the
decay width of the top quark, where all effects associated with the $b$ quark
mass are included without resorting to a mass expansion. Our results agree with
the analytical results available for the O(\alpha_s) correction to the top
quark width.

</DOC>
<DOC>
<DOCNO> 100104 </DOCNO>
The Concept of a Noncommutative Riemann Surface


  We consider the compactification M(atrix) theory on a Riemann surface Sigma
of genus g>1. A natural generalization of the case of the torus leads to
construct a projective unitary representation of pi_1(\Sigma), realized on the
Hilbert space of square integrable functions on the upper half--plane. A
uniquely determined gauge connection, which in turn defines a gauged sl_2(R)
algebra, provides the central extension. This has a geometric interpretation as
the gauge length of a geodesic triangle, and corresponds to a 2-cocycle of the
2nd Hochschild cohomology group of the Fuchsian group uniformizing Sigma. Our
construction can be seen as a suitable double-scaling limit N\to\infty,
k\to-\infty of a U(N) representation of pi_1(Sigma), where k is the degree of
the associated holomorphic vector bundle, which can be seen as the higher-genus
analog of 't Hooft's clock and shift matrices of QCD. We compare the above
mentioned uniqueness of the connection with the one considered in the
differential-geometric approach to the Narasimhan-Seshadri theorem provided by
Donaldson. We then use our infinite dimensional representation to construct a
C^\star-algebra which can be interpreted as a noncommutative Riemann surface
Sigma_\theta. Finally, we comment on the extension to higher genus of the
concept of Morita equivalence.

</DOC>
<DOC>
<DOCNO> 40122 </DOCNO>
The first determination of Generalized Polarizabilities of the proton by


  Absolute differential cross sections for the reaction (e+p -> e+p+gamma) have
been measured at a four-momentum transfer with virtuality Q^2=0.33 GeV^2 and
polarization \epsilon = 0.62 in the range 33.6 to 111.5 MeV/c for the momentum
of the outgoing photon in the photon-proton center of mass frame. The
experiment has been performed with the high resolution spectrometers at the
Mainz Microtron MAMI. From the photon angular distributions, two structure
functions which are a linear combination of the generalized polarizabilities
have been determined for the first time.

</DOC>
<DOC>
<DOCNO> 9642 </DOCNO>
Switching and symmetry breaking behaviour of discrete breathers in


  We investigate the roto-breathers recently observed in experiments on
Josephson ladders subjected to a uniform transverse bias current. We describe
the switching mechanism in which the number of rotating junctions increases. In
the region close to switching we find that frequency locking, period doubling,
quasi-periodic behaviour and symmetry breaking all occur. This suggests that a
chaotic dynamic occurs in the switching process. Close to switching the induced
flux increases sharply and clearly plays an important role in the switching
mechanism. We also find three critical frequencies which are independent of the
dissipation constant $\alpha$, provided that $\alpha$ is not too large.

</DOC>
<DOC>
<DOCNO> 123229 </DOCNO>
Galactic dynamos with captured magnetic flux and an accretion flow


  We examine the behaviour of an axisymmetric galactic dynamo model with a
radial accretion flow in the disc. We also introduce a vertical magnetic flux
through the galactic midplane, to simulate the presence of a large scale
magnetic field trapped by the galaxy when forming. The trapped vertical flux is
conserved and advected towards the disc centre by the radial flow. We confirm
that accretion flows of magnitude several km/s through a significant part of
the galactic disc can markedly inhibit dynamo action. Moreover, advection of
the vertical flux in general results in mixed parity galactic fields. However,
the effect is nonlinear and non-additive -- global magnetic field energies are
usually significantly smaller that the sum of purely dynamo generated and
purely advected field energies. For large inflow speeds, a form of
`semi-dynamo' action may occur.
  We apply our results to the accumulation and redistribution, by a radial
inflow, of a vertical magnetic flux captured by the Galactic disc. Taking
representative values, it appears difficult to obtain mean vertical fields near
the centre of the Milky Way that are much in excess of 10 microgauss, largely
because the galactic dynamo and turbulent magnetic diffusion modify the
external magnetic field before it can reach the disc centre.

</DOC>
<DOC>
<DOCNO> 117671 </DOCNO>
Gravitational microlensing source limb-darkening and


  There is increasing interest in extended source effects in microlensing
events, as probes of the unresolved sources. Previous work has either presumed
a uniform source, or else required an approximate or numerical treatment of the
amplification function averaged over the source disk. In this paper, I present
analytic expressions for the angle-averaged amplification functions for the
rotationally-symmetric intensity and polarization cases.
  These integrals will allow us to use the technology of inverse problems to
study the source limb-darkening and limb-polarization functions.

</DOC>
<DOC>
<DOCNO> 69464 </DOCNO>
Antimatter Regions in the Early Universe and Big Bang Nucleosynthesis


  We have studied big bang nucleosynthesis in the presence of regions of
antimatter. Depending on the distance scale of the antimatter region, and thus
the epoch of their annihilation, the amount of antimatter in the early universe
is constrained by the observed abundances. Small regions, which annihilate
after weak freezeout but before nucleosynthesis, lead to a reduction in the 4He
yield, because of neutron annihilation. Large regions, which annihilate after
nucleosynthesis, lead to an increased 3He yield. Deuterium production is also
affected but not as much. The three most important production mechanisms of 3He
are 1) photodisintegration of 4He by the annihilation radiation, 2) pbar-4He
annihilation, and 3) nbar-4He annihilation by "secondary" antineutrons produced
in anti-4He annihilation. Although pbar-4He annihilation produces more 3He than
the secondary nbar-4He annihilation, the products of the latter survive later
annihilation much better, since they are distributed further away from the
annihilation zone.

</DOC>
<DOC>
<DOCNO> 118278 </DOCNO>
Nuclear Matter and its Role in Supernovae, Neutron Stars and Compact


  The equation of state (EOS) of dense matter plays an important role in the
supernova phenomenon, the structure of neutron stars, and in the mergers of
compact objects (neutron stars and black holes). During the collapse phase of a
supernova, the EOS at subnuclear densities controls the collapse rate, the
amount of deleptonization and thus the size of the collapsing core and the
bounce density. Properties of nuclear matter that are especially crucial are
the symmetry energy and the nuclear specific heat. The nuclear
incompressibility, and the supernuclear EOS, play supporting roles. In a
similar way, although the maximum masses of neutron stars are entirely
dependent upon the supernuclear EOS, other important structural aspects are
more sensitive to the equation of state at nuclear densities. The radii,
moments of inertia, and the relative binding energies of neutron stars are, in
particular, sensitive to the behavior of the nuclear symmetry energy. The
dependence of the radius of a neutron star on its mass is shown to critically
influence the outcome of the compact merger of two neutron stars or a neutron
star with a small mass black hole. This latter topic is especially relevant to
this volume, since it stems from research prompted by the tutoring of David
Schramm a quarter century ago.

</DOC>
<DOC>
<DOCNO> 11052 </DOCNO>
Spin glass like transition in a highly concentrated Fe-C nanoparticle


  A highly concentrated (17 vol.%) Fe-C nano-particle system, with a narrow
size distribution $d = 5.4\pm 0.4$ nm, has been investigated using magnetic ac
susceptibility measurements covering a wide range of frequencies (17 mHz - 170
Hz). A dynamic scaling analysis gives evidence for a phase transition to a low
temperature spin-glass-like phase. The critical exponents associated with the
transition are $z\nu = 10.5 \pm 2$ and $\beta = 1.1 \pm 0.2$. The reason why
the scaling analysis works for this sample, while it may not work for other
samples exhibiting collective behavior as evidenced by aging phenomena, is that
the single particle contribution to $\chi''$ is vanishingly small for $T>T_g$
and hence all slow dynamics is due to collective behavior. This criterion can
only be fulfilled for a highly concentrated nano-particle sample with a narrow
size distribution.

</DOC>
<DOC>
<DOCNO> 100527 </DOCNO>
Quantum Affine (Super)Algebras $U_q(A_{1}^{(1)})$ and $U_q(C(2)^{(2)})$


  We show that the quantum affine algebra $U_{q}(A_{1}^{(1)})$ and the quantum
affine superalgebra $U_{q}(C(2)^{(2)})$ admit a unified description. The
difference between them consists in the phase factor which is equal to 1 for
$U_{q}(A_{1}^{(1)})$ and it is equal to -1 for $U_{q}(C(2)^{(2)})$. We present
such a description for the actions of the braid group, for the construction of
Cartan-Weyl generators and their commutation relations, as well for the
extremal projector and the universal R-matrix. We give also a unified
description for the 'new realizations' of these algebras together with explicit
calculations of corresponding R-matrices.

</DOC>
<DOC>
<DOCNO> 152238 </DOCNO>
String Field Theory and Perturbative Dynamics of Noncommutative Field


  The perturbative dynamics of noncommutative field theory (NCFT) is discussed
from a point view of string field theory. As in the commutative case it is
inevitable to introduce a closed string, which may be described as a bound
state of two noncommutative open strings. We point out that the closed string,
interacting nontrivially with the open string, plays an essential role in the
ultraviolet region. The contribution of the closed string is responsible for
the discrepancy between the NCFT and the string field theory. It clarifies the
controversial issues associated with the ultraviolet/infrared (UV/IR) behaviour
of the perturbative dynamics of the NCFT.

</DOC>
<DOC>
<DOCNO> 119797 </DOCNO>
FUSE Observations of the HD Molecule toward HD 73882


  The Lyman and Werner band systems of deuterated molecular hydrogen (HD) occur
in the far UV range below 1200 A. The high sensitivity of the FUSE mission can
give access, at moderate resolution, to hot stars shining through translucent
clouds, in the hope of observing molecular cores in which deuterium is
essentially in the form of HD. Thus, the measurement of the HD/H2 ratio may
become a new powerful tool to evaluate the deuterium abundance, D/H, in the
interstellar medium. We report here on the detection of HD toward the high
extinction star HD 73882 [E(B-V)=0.72]. A preliminary analysis is presented.

</DOC>
<DOC>
<DOCNO> 69481 </DOCNO>
Dense Nuclear Matter: Landau Fermi-Liquid Theory and Chiral Lagrangian


  The relation between the effective chiral Lagrangian whose parameters scale
according to Brown and Rho scaling("BR scaling") and Landau Fermi-liquid theory
for hadronic matter is discussed in order to make a basis to describe the
fluctuations under the extreme condition relevant to neutron stars. It is
suggested that BR scaling gives the background around which the fluctuations
are weak. A simple model with BR-scaled parameters is constructed and
reproduces the properties of the nuclear ground state at normal nuclear matter
density successfully. It shows that the tree level in the model Lagrangian is
enough to describe the fluctuations around BR-scaled background. The model
Lagrangian is consistent thermodynamically and reproduces relativistic Landau
Fermi-liquid properties. Such points are important for dealing with hadronic
matter under extreme condition. On the other hand it is shown that the vector
current obtained from the chiral Lagrangian is the same as that obtained from
Landau-Migdal approach. We can determine the Landau parameter in terms of
BR-scaled parameter. However these two approaches provide different results,
when applied to the axial charge. The numerical difference is small. It shows
that the axial response is not included properly in the Landau-Migdal approach.

</DOC>
<DOC>
<DOCNO> 170069 </DOCNO>
Hidden-variable theorems for real experiments


  It has recently been questioned whether the Kochen-Specker theorem is
relevant to real experiments, which by necessity only have finite precision. We
give an affirmative answer to this question by showing how to derive
hidden-variable theorems that apply to real experiments, so that non-contextual
hidden variables can indeed be experimentally disproved. The essential point is
that for the derivation of hidden-variable theorems one does not have to know
which observables are really measured by the apparatus. Predictions can be
derived for observables that are defined in an entirely operational way.

</DOC>
<DOC>
<DOCNO> 8729 </DOCNO>
External fluctuations in front dynamics with inertia: The overdamped


  We study the dynamics of fronts when both inertial effects and external
fluctuations are taken into account. Stochastic fluctuations are introduced as
multiplicative noise arising from a control parameter of the system. Contrary
to the non-inertial (overdamped) case, we find that important features of the
system, such as the velocity selection picture, are not modified by the noise.
We then compute the overdamped limit of the underdamped dynamics in a more
careful way, finding that it does not exhibit any effect of noise either. Our
result poses the question as to whether or not external noise sources can be
measured in physical systems of this kind.

</DOC>
<DOC>
<DOCNO> 40353 </DOCNO>
Centrality dependence of K+ produced in Pb+Pb collisions at 158 GeV per


  The NA52 collaboration searches for a discontinuous behaviour of charged
kaons produced in Pb+Pb collisions at 158 A GeV as a function of the impact
parameter, which could reveal a hadron to quark-gluon plasma (QGP) phase
transition. The K+ yield is found to grow proportional to the number of
participating ('wounded') nucleons N, above N=100. Previous NA52 data agree
with the above finding and show a discontinuous behaviour in the kaon
centrality dependence near N=100, marking the onset of strangeness enhancement
-over e.g. p+A data at the same \sqrt{s}- in a chemically equilibrated phase.

</DOC>
<DOC>
<DOCNO> 101290 </DOCNO>
Symmetry Classes of Alternating Sign Matrices


  An alternating sign matrix is a square matrix satisfying (i) all entries are
equal to 1, -1 or 0; (ii) every row and column has sum 1; (iii) in every row
and column the non-zero entries alternate in sign. The 8-element group of
symmetries of the square acts in an obvious way on square matrices. For any
subgroup of the group of symmetries of the square we may consider the subset of
matrices invariant under elements of this subgroup. There are 8 conjugacy
classes of these subgroups giving rise to 8 symmetry classes of matrices. R. P.
Stanley suggested the study of those alternating sign matrices in each of these
symmetry classes. We have found evidence suggesting that for six of the
symmetry classes there exist simple product formulas for the number of
alternating sign matrices in the class. Moreover the factorizations of certain
of their generating functions point to rather startling connections between
several of the symmetry classes and cyclically symmetric plane partitions.

</DOC>
<DOC>
<DOCNO> 39757 </DOCNO>
Physics of CP Violation and Rare Decays


  Lectures note for Cargese 99 Summer School Particle Physics: Ideas and Recent
Development NATO Advanced Institute, Corsica, July 26-August 7, 1999

</DOC>
<DOC>
<DOCNO> 117507 </DOCNO>
On the gamma-ray fluxes expected from Cassiopeia A


  Based on the results of our previous study of the broad band synchrotron
emission of Cas A in the framework of a spatial inhomogeneous model, we
calculate the fluxes of gamma-radiation that can be expected from this
supernova remnant in different energy bands. We show that at energies below 10
GeV gamma-ray fluxes detectable by forthcoming space-borne detectors should be
produced due to bremsstrahlung of radio emitting electrons. We predict that the
power-law index of the photon flux in the GeV region should be hard, close to
the index ~2.2 expected for the acceleration spectrum of the electrons. Photon
fluxes accessible to future ground-based gamma-ray detectors could also be
expected at very high energies. The fluxes to be expected due to bremsstrahlung
and inverse Compton radiation of relativistic electrons at TeV energies should
be very steep, and strongly dependent on the characteristic magnetic fields in
Cas A. We could expect also significant fluxes of pi^0 -decay gamma-rays
produced by relativistic protons. These fluxes may extend with a hard spectrum
beyond TeV energies as far as the protons would be accelerated to energies
beyond 100 TeV. The hardness of the gamma-ray spectrum at TeV energies could in
principle allow one to distinguish between electronic and hadronic origins of
those gamma-rays. We discuss also other implications, such as relativistic
particle content, or physical parameters in the source, that could be derived
from future gamma-ray flux measurements in different energy bands.

</DOC>
<DOC>
<DOCNO> 100735 </DOCNO>
Amalgamation bases for nil-2 groups of odd exponent


  We study the strong, weak, and special amalgamation bases in the varieties of
nilpotent groups of class two and exponent n, where n is odd. The main result
is a characterization of the special amalgamation bases for these varieties. We
also characterize the weak and strong bases. For special amalgamation bases, we
show that there are groups which are special bases in varieties of finite
exponent but not in the variety of all nil-2 groups, whereas for weak and
strong bases we show this is not the case. We also show that in these
varieties, as well as the variety of all nil-2 groups, a group has an absolute
closure (in the sense of Isbell) if and only if it is already absolutely
closed, i.e. if and only if it is a special amalgamation base.

</DOC>
<DOC>
<DOCNO> 123287 </DOCNO>
Error estimation for the MAP experiment


  We report here the first full sky component separation and CMB power spectrum
estimation using a Wiener filtering technique on simulated data from the
upcoming MAP experiment, set to launch in early 2001. The simulations included
contributions from the three dominant astrophysical components expected in the
five MAP spectral bands, namely CMB radiation, Galactic dust, and synchrotron
emission. We assumed a simple homogeneous and isotropic white noise model and
performed our analysis up to a spherical harmonic multipole lmax=512 on the
fraction of the sky defined by b>20 degrees. We find that the reconstruction
errors are reasonably well fitted by a Gaussian with an rms of 24 $\mu $K, but
with significant deviations in the tails. Our results further support the
predictions on the resulting CMB power spectrum of a previous estimate by
Bouchet and Gispert (1999), which entailed a number of assumptions this work
removes.

</DOC>
<DOC>
<DOCNO> 122871 </DOCNO>
Decay of inhomogeneities from the spin-torsion fluctuations in the early


  The spin-torsion fluctuations are shown to act as source of decay of
inhomogeneities in the early stages of inflationary de Sitter universe.This
seems to be a resul of the repulsive nature of the spin-torsion effects.This
result is shown through the investigation of the evolution equation of density
perturbations in Einstein-Cartan cosmology.We also show that it is possible to
place limits on torsion in the universe from the CMBR temperature anisotropy
from the computations we made.The decay of inhomogeneities is not enough
however to stop the structure formation as galaxies because the growth of
inhomogeneitis dominates the torsion effects and the only effect of torsion
seems to decrease very weakly the speed of formation of galaxies.

</DOC>
<DOC>
<DOCNO> 117718 </DOCNO>
Broad-band BeppoSAX observation of the low-mass X-ray binary X1822-371


  Results of a 1997 September 9-10 BeppoSAX observation of the 5.57 hr low-mass
X-ray binary (LMXRB) X1822-371 are presented. The 0.3-40 keV spectrum is
unusually complex and cannot be fit by any of the standard models applied to
other LMXRB. At least two components are required. One component has a shape
consistent with that expected from the Comptonization of an input soft (Wein)
spectrum while the other, contributing ~40% of the 1-10 keV flux, is consistent
with being a blackbody. In addition, there is a ``dip'' in the spectrum which
can be modeled by a 1.33 +0.05 -0.11 keV absorption edge with an optical depth,
tau, of 0.28 +/- 0.06. If the same model is fit to ASCA Solid-State Imaging
Spectrometer spectra obtained in 1993 and 1996, then reasonable fits are also
obtained, with a similar absorption feature required. The nature of this
feature is highly uncertain; its energy corresponds to the K-edges of highly
ionized Ne x and neutral Mg, or to an L-edge of moderately ionized Fe.
Surprisingly, no strong (tau > 0.05) Fe-K or (tau > 0.18) O-K edges are
visible. The folded lightcurve of X1822-371 is similar to previous
observations, except that no strong softening is seen near the eclipse. An
updated orbital ephemeris is provided.

</DOC>
<DOC>
<DOCNO> 7779 </DOCNO>
Droplets in the coexistence region of the two-dimensional Ising model


  The two-dimensional Ising model with fixed magnetization is studied using
Monte Carlo techniques. At the coexistence line, the macroscopic, extensive
droplet of minority spins becomes thermally unstable by breaking up into
microscopic clusters. Intriguing finite--size effects as well as singularities
of thermal and cluster properties associated with the transition are discussed.

</DOC>
<DOC>
<DOCNO> 170374 </DOCNO>
Solvable PT symmetric Hamiltonians


  Brief review is given of my recent results on solvable models within the so
called PT symmetric version of quantum mechanics.

</DOC>
<DOC>
<DOCNO> 67934 </DOCNO>
Oblique Parameter Constraints on Large Extra Dimensions


  We consider the Kaluza-Klein scenario in which gravity propagates in the
$4+n$ dimensional bulk of spacetime and the Standard Model particles are
confined to a 3-brane. We calculate the gauge boson self-energy corrections
arising from the exchange of virtual gravitons and present our results in the
$STU$-formalism. We find that the new physics contributions to $S$, $T$ and $U$
decouple in the limit that the string scale $M_S$ goes to infinity. The oblique
parameters constrain the lower limit on $M_S$. Taking the quantum gravity
cutoff to be $M_S$,
 $S$-parameter constraints impose $M_S>1.55$ TeV for $n=2$ at the 1$\sigma$
level. $T$-parameter constraints impose $M_S>1.25 (0.75)$ TeV for $n=3 (6)$.

</DOC>
<DOC>
<DOCNO> 10116 </DOCNO>
On the existence of a variational principle for deterministic cellular


  It is shown that a variety of deterministic cellular automaton models of
highway traffic flow obey a variational principle which states that, for a
given car density, the average car flow is a non-decreasing function of time.
This result is established for systems whose configurations exhibits local jams
of a given structure. If local jams have a different structure, it is shown
that either the variational principle may still apply to systems evolving
according to some particular rules, or it could apply under a weaker form to
systems whose asymptotic average car flow is a well-defined function of car
density. To establish these results it has been necessary to characterize among
all number-conserving cellular automaton rules which ones may reasonably be
considered as acceptable traffic rules. Various notions such as free-moving
phase, perfect and defective tiles, and local jam play an important role in the
discussion. Many illustrative examples are given.

</DOC>
<DOC>
<DOCNO> 10501 </DOCNO>
Multi-mode dynamics of a coupled ultracold atomic-molecular system


  We analyze the coherent multi-mode dynamics of a system of coupled atomic and
molecular Bose gases. Starting from an atomic Bose-Einstein condensate with a
small thermal component, we observe a complete depletion of the atomic and
molecular condensate modes on a short time scale due to significant population
of excited states. Giant coherent oscillations between the two condensates for
typical parameters are almost completely suppressed. Our results cast serious
doubts on the common use of the 2-mode model for description of coupled
ultracold atomic-molecular systems and should be considered when planning
future experiments with ultracold molecules.

</DOC>
<DOC>
<DOCNO> 85125 </DOCNO>
Group-theoretical structure of quantum measurements and equivalence


  The transverse group associated to some continuous quantum measuring
processes is analyzed in the presence of nonvanishing gravitational fields.
This is done considering, as an exmaple, the case of a particle whose
coordinates are being monitored. Employing the so called restricted path
integral formalism, it will be shown that the measuring process could always
contain information concerning the gravitational field. In other words, it
seems that with the presence of a measuring process the equivalence principle
may, in some cases, break down. The relation between the breakdown of the
equivalence principle, at quantum level, and the fact that the gravitational
field could act always as a decoherence environment, is also considered. The
phenomena of quantum beats of quantum optics will allow us to consider the
possibility that the experimental corroboration of the equivalence principle at
quantum level could be taken as an indirect evidence in favor of the
quantization of the gravitational field, i.e., the quantum properties of this
field avoid the violation of the equivalence principle.

</DOC>
<DOC>
<DOCNO> 71153 </DOCNO>
J/psi and psi(2S) Production and Polarization at the Tevatron


  The NRQCD factorization approach for quarkonium production at hadron
colliders is reviewed. The prediction of J/psi and psi(2S) transverse
polarization at large transverse momentum is confronted with recent
experimental data, and potential shortcomings of the theoretical analysis are
discussed.

</DOC>
<DOC>
<DOCNO> 102325 </DOCNO>
2-extensions with many points


  We give defining equations for function fields over finite fields with many
rational places. They are obtained from composita of quadratic extensions of
the rational function field.

</DOC>
<DOC>
<DOCNO> 12579 </DOCNO>
Critical depinning force and vortex lattice order in disordered


  We simulate the ordering of vortices and its effects on the critical current
in superconductors with varied vortex-vortex interaction strength and varied
pinning strengths for a two-dimensional system. For strong pinning the vortex
lattice is always disordered and the critical depinning force only weakly
increases with decreasing vortex-vortex interactions. For weak pinning the
vortex lattice is defect free until the vortex-vortex interactions have been
reduced to a low value, when defects begin to appear with a simultaneous rapid
increase in the critical depinning force. In each case the depinning force
shows a maximum for non-interacting vortices. The relative height of the peak
increases and the peak width decreases for decreasing pinning strength in
excellent agreement with experimental trends associated with the peak effect.
We show that scaling relations exist between the distance between defects in
the vortex lattice and the critical depinning force.

</DOC>
<DOC>
<DOCNO> 11580 </DOCNO>
Phase diagram of disordered fermion model on two-dimensional square


  A fermion model with random on-site potential defined on a two-dimensional
square lattice with $\pi$-flux is studied. The continuum limit of the model
near the zero energy yields Dirac fermions with random potentials specified by
four independent coupling constants. The basic symmetry of the model is
time-reversal invariance. Moreover, it turns out that the model has enhanced
(chiral) symmetry on several surfaces in the four-dimensional space of the
coupling constants. It is shown that one of the surfaces with chiral symmetry
has Sp(n)$\times$Sp(n) symmety whereas others have U(2n) symmetry, both of
which are broken to Sp(n), and the fluctuation around a saddle point is
described, respectively, by Sp($n)_2$ WZW model and U(2n)/Sp(n) nonlinear sigma
model. Based on these results, we propose a phase diagram of the model.

</DOC>
<DOC>
<DOCNO> 8930 </DOCNO>
From second to first order transitions in a disordered quantum magnet


  We study the spin-glass transition in a disordered quantum model. There is a
region in the phase diagram where quantum effects are small and the phase
transition is second order, as in the classical case. In another region,
quantum fluctuations drive the transition first order. Across the first order
line the susceptibility is discontinuous and shows hysteresis. Our findings
reproduce qualitatively observations on LiHo$_x$Y$_{1-x}$F$_4$. We also discuss
a marginally stable spin-glass state and derive some results previously
obtained from the real-time dynamics of the model coupled to a bath.

</DOC>
<DOC>
<DOCNO> 70078 </DOCNO>
Yukawa Unification and Unstable Minima of the Supersymmetric Scalar


  Motivated by the possibilities of $b-\tau$ or $t-b-\tau$ Yukawa unification
in the supersymmetric Grand Unified Theories, we consider the dangerous
directions of the supersymmetric potential for large values of $\tan\beta (\geq
30)$, in two versions of the minimal supergravity model with and without common
soft breaking scalar masses at the GUT scale, where the potential may become
unbounded from below. We find that for the common trilinear coupling $A_0 \leq
0$ the requirement of $b-\tau$ unification in conjunction with the stability
condition on the potential yields highly restrictive sparticle spectra with
upper, and in many cases, lower bounds stronger than the available experimental
lower bounds, on the soft SUSY breaking common scalar mass and the common
gaugino mass. Over a significant region of the parameter space, the model
becomes even more restrictive if the common sfermion soft mass is different
from the soft mass for the Higgs sector. We also find that the bulk of this
restricted parameter space can be probed at the LHC. Im models with $t-b-\tau$
Yukawa unification, $A_0 \leq 0$ is ruled out from potential constraints.

</DOC>
<DOC>
<DOCNO> 72131 </DOCNO>
Lectures on the Theory of Non-leptonic B Decays


  These notes provide a pedagogical introduction to the theory of non-leptonic
heavy-meson decays recently proposed by Beneke, Buchalla, Sachrajda and myself.
We provide a rigorous basis for factorization for a large class of non-leptonic
two-body B-meson decays in the heavy-quark limit. The resulting factorization
formula incorporates elements of the naive factorization approach and the
hard-scattering approach, and allows us to compute systematically radiative
(``non-factorizable'') corrections to naive factorization for decays such as
B->D+pi and B->pi+pi.

</DOC>
<DOC>
<DOCNO> 13448 </DOCNO>
Superconducting fluctuations at low temperature


  The effect of fluctuations on the transport and thermodynamic properties of
two-dimensional superconductors in a magnetic field is studied at low
temperature. The fluctuation conductivity is calculated in the framework of the
perturbation theory with the help of usual diagram technique. It is shown that
in the dirty case the Aslamazov-Larkin, Maki-Thomson and Density of States
contributions are of the same order. At extremely low temperature, the total
fluctuation correction to the normal conductivity is negative in the dirty
limit and depends on the external magnetic field logarithmically. In the
non-local clean limit, the Aslamazov-Larkin contribution to conductivity is
evaluated with the aid of the Helfand-Werthamer theory. The longitudinal and
Hall conductivities are found. The fluctuating magnetization is calculated in
the one-loop and two-loop approximations.

</DOC>
<DOC>
<DOCNO> 151109 </DOCNO>
R^4 terms in 11 dimensions and conformal anomaly of (2,0) theory


  Using AdS_7/CFT_6 correspondence we discuss computation of a subleading O(N)
term in the scale anomaly of (2,0) theory describing N coincident M5 branes.
While the leading O(N^3) contribution to the anomaly is determined by the
supergravity action, the O(N) contribution comes from a particular R^4 term (8d
Euler density) in the 11-dimensional effective action. This R^4 term is argued
to be part of the same superinvariant as the P-odd C_3 R^4 term known to
produce O(N) contribution to the R-symmetry anomaly of (2,0) theory. The known
results for R-anomaly suggest that the total scale anomaly extrapolated to N=1
should be the same as the anomaly of a single free (2,0) tensor multiplet. A
proposed explanation of this agreement is that the coefficient 4N^3 in the
anomaly (which was found previously to be also the ratio of the 2-point and
3-point graviton correlators in the (2,0) theory and in the free tensor
multiplet theory) is shifted to 4N^3 -3N.

</DOC>
<DOC>
<DOCNO> 68040 </DOCNO>
Theory of radiative B decays


  Theory of charmless radiative B decays is reviewed. Existence of uncontrolled
non-perturbative effects in the inclusive rate at O(alpha_s) is reminded.

</DOC>
<DOC>
<DOCNO> 118044 </DOCNO>
The Spatial Distribution of Atomic Carbon Emission in the Giant


  We have mapped a giant molecular cloud in the giant HII region NGC 604 in M33
in the 492 GHz ^3P_1 -- ^3P_0 transition of neutral atomic carbon using the
James Clerk Maxwell Telescope. We find the distribution of the [CI] emission to
be asymmetric with respect to the CO J=1--0 emission, with the peak of the [CI]
emission offset towards the direction of the center of the HII region. In
addition, the line ratio I_{[CI]}/I_{CO} is highest (~ 0.2) facing the HII
region and lowest (< 0.1) away from it. These asymmetries indicate an edge-on
morphology where the [CI] emission is strongest on the side of the cloud facing
the center of the HII region, and not detected at all on the opposite side This
suggests that the sources of the incident flux creating C from the dissociation
of CO are the massive stars of the HII region. The lowest line ratios are
similar to what is observed in Galactic molecular clouds, while the highest are
similar to starburst galaxies and other regions of intense star formation. The
column density ratio, N(C)/N(H_2) is a few times 10^{-6}, in general agreement
with models of photodissociation regions.

</DOC>
<DOC>
<DOCNO> 151649 </DOCNO>
Pulse interaction in nonlinear vacuum electrodynamics


  The energy-momentum conservation law is used to investigate the interaction
of pulses in the framework of nonlinear electrodynamics with Lorentz-invariant
constitutive relations. It is shown that for the pulses of the arbitrary shape
the interaction results in phase shift only.

</DOC>
<DOC>
<DOCNO> 122064 </DOCNO>
The circumnuclear X-ray reflectors in NGC 1068 and the Circinus Galaxy


  The ASCA and BeppoSAX spectra of the Circinus Galaxy and NGC 1068 are
analysed and compared with photoionization models based on cloudy. In the case
of Circinus, a single, mildly ionized reflector can account for the line
spectrum, while in NGC 1068 at least three different reflectors (with different
ionization states) are needed. We suggest that the reflector in Circinus, and
the low ionized one in NGC1068 are the inner and visible part of the material
responsible for the X-ray absorption. With this assumption, we estimate for the
inner radius of the absorber a value of 0.2 pc for Circinus and of a few
parsecs for NGC 1068.

</DOC>
<DOC>
<DOCNO> 39624 </DOCNO>
Some problems in plasma suppression of beam-beam interactions at muon


  The idea of plasma suppression of beam-beam effects at muon colliders is
discussed. It is shown that one should take into account collisions in the
plasma that were ignored before. Rough estimates show that this effect leads to
a fast ``recovery'' of the beam magnetic field. For beam parameters
characteristic for muon colliders the suppression of the magnetic component of
the beam field (1/2 of the total force) is almost absent. It is also shown that
the presence of the dense plasma (Li jet) at the interaction point leads to
enormous hadronic background (due to photo-nuclear reactions) in the detector,
about 10^{7} particles per crossing at large angles which creates serious
problems for experimentation.

</DOC>
<DOC>
<DOCNO> 179013 </DOCNO>
Pair creation and plasma oscillations


  We describe aspects of particle creation in strong fields using a quantum
kinetic equation with a relaxation-time approximation to the collision term.
The strong electric background field is determined by solving Maxwell's
equation in tandem with the Vlasov equation. Plasma oscillations appear as a
result of feedback between the background field and the field generated by the
particles produced. The plasma frequency depends on the strength of the initial
background field and the collision frequency, and is sensitive to the necessary
momentum-dependence of dressed-parton masses.

</DOC>
<DOC>
<DOCNO> 7617 </DOCNO>
Superconductivity in Ferromagnetic RuSr_2GdCu_2O_8


  The phase diagram of temperature versus exchange field is obtained within a
BCS model for d-wave superconductivity in CuO_2 layers which is coupled to
ferromagnetic RuO_2 layers in RuSr_2GdCu_2O_8. It is found that the
Fulde-Ferrell-Larkin-Ovchinnikov state is very sensitive to the band filling
factor. For strong exchange field, we point out that superconductivity could
only exist in the interfaces between ferromagnetic domains. The magnetization
curve is calculated and its comparison with experiment is discussed. We also
propose the measuring of tunneling conductance near a single unitary impurity
to detect the strength of the exchange interaction.

</DOC>
<DOC>
<DOCNO> 119401 </DOCNO>
Infrared Observations of Hot Gas and Cold Ice toward the Low Mass


  We have obtained the full 1-200 um spectrum of the low luminosity (36 Lsun)
Class I protostar Elias 29 in the Rho Ophiuchi molecular cloud. It provides a
unique opportunity to study the origin and evolution of interstellar ice and
the interrelationship of interstellar ice and hot core gases around low mass
protostars. We see abundant hot CO and H2O gas, as well as the absorption bands
of CO, CO2, H2O and ``6.85 um'' ices. We compare the abundances and physical
conditions of the gas and ices toward Elias 29 with the conditions around
several well studied luminous, high mass protostars. The high gas temperature
and gas/solid ratios resemble those of relatively evolved high mass objects
(e.g. GL 2591). However, none of the ice band profiles shows evidence for
significant thermal processing, and in this respect Elias 29 resembles the
least evolved luminous protostars, such as NGC 7538 : IRS9. Thus we conclude
that the heating of the envelope of the low mass object Elias 29 is
qualitatively different from that of high mass protostars. This is possibly
related to a different density gradient of the envelope or shielding of the
ices in a circumstellar disk. This result is important for our understanding of
the evolution of interstellar ices, and their relation to cometary ices.

</DOC>
<DOC>
<DOCNO> 67905 </DOCNO>
Non-equilibrium dynamics of hot Abelian Higgs model


  The real-time dynamics of finite-temperature gauge theories can be
approximated, to leading-order accuracy in the coupling constants, by a
classical field theory with the hard thermal loop Lagrangian. I show how this
approach can be used in numerical lattice simulations to study dynamics of the
Abelian Higgs model in or slightly out of equilibrium.

</DOC>
<DOC>
<DOCNO> 99978 </DOCNO>
Classification des triples de Manin pour les alg\`ebres de Lie


  We study real and complex Manin triples for a complex reductive Lie algebra,
$\g$. The first part includes, and extends to complex Manin triples, our
earlier work [De]. First, we generalize results of E. Karolinsky, on the
classification of Lagrangian subalgebras (cf.[K1], [K3]). Then we show that, if
$\g$ is non commutative, one can attach, to each Manin triple in $\g$, another
one for a strictly smaller reductive complex Lie subalgebra of $\g$. This gives
a powerful tool for induction. Then we classify complex Manin triples, in terms
of what we call generalized Belavin-Drinfeld data. In particular this
generalizes, by other methods, the classification of A. Belavin and G. Drinfeld
of certain $R$-matrices, i.e. the solutions of modified triangle equations for
constants (cf [BD], Theorem 6.1). We get also results for real Manin triples.
In passing, one retrieves a result of A. Panov [P1] which classifies certain
Lie bialgebras structures on a real simple Lie algebra.

</DOC>
<DOC>
<DOCNO> 11573 </DOCNO>
Hausdorff dimension of critical fluctuations in abelian gauge theories


  The geometric properties of the critical fluctuations in abelian gauge
theories such as the Ginzburg-Landau model are analyzed in zero background
field. Using a dual description, we obtain scaling relations between exponents
of geometric and thermodynamic nature. In particular we connect the anomalous
scaling dimension $\eta$ of the dual matter field to the Hausdorff dimension
$D_H$ of the critical fluctuations, {\it which are fractal objects}. The
connection between the values of $\eta$ and $D_H$, and the possibility of
having a thermodynamic transition in finite background field, is discussed.

</DOC>
<DOC>
<DOCNO> 122158 </DOCNO>
Accurate masses of very low mass stars: IV Improved mass-luminosity


  We present improved visual and near-infrared empirical mass-luminosity
relations for very low mass stars (M$<$0.6~\Msol). These relations make use of
all stellar masses in this range known with better than 10% accuracy, most of
which are new determinations with 0.2 to 5% accuracy from our own programme,
presented in a companion paper.
  As predicted by stellar structure models, the metallicity dispersion of the
field populations induces a large scatter around the mean V band relation,
while the infrared relations are much tighter. The agreement of the observed
infrared mass-luminosity relations with the theoretical relations of Baraffe et
al. (1998) and Siess et al. (2000) is impressive, while we find an increasingly
significant discrepancy in the V band for decreasing masses. The theoretical
mass-luminosity relation which is insufficiently steep, and has introduced some
errors in the local stellar mass functions derived from V band luminosity
functions.

</DOC>
<DOC>
<DOCNO> 119614 </DOCNO>
On The Synchrotron Self-Compton Emission from Relativistic Shocks and


  We consider the effects of inverse Compton scattering of synchrotron photons
from relativistic electrons in GRB afterglows. We compute the spectrum of the
inverse Compton emission and find that it can dominate the total cooling rate
of the afterglow for several months or even years after the initial explosion.
We demonstrate that the presence of strong inverse Compton cooling can be
deduced from the effect it has on the time-evolution of the cooling break in
the synchrotron spectral component, and therefore on the optical and X-ray
afterglow lightcurves. We then show how the physical interpretation of the
observed characteristics of the synchrotron spectrum must be modified to take
into consideration this extra source of cooling, and give a revised
prescription for computing physical parameters characterizing the expanding
shock wave from the observed quantities. We find that for a given set of
observables (synchrotron break frequencies and fluxes) there is either no
consistent physical interpretation or two of them. Finally we discuss the
prospects of directly detecting the inverse Compton emission with Chandra. We
argue that such a detection is possible for GRBs exploding in a reasonably
dense (n>1 cm^-3) medium.

</DOC>
<DOC>
<DOCNO> 84393 </DOCNO>
(2,2)-Formalism of General Relativity: An Exact Solution


  I discuss the (2,2)-formalism of general relativity based on the
(2,2)-fibration of a generic 4-dimensional spacetime of the Lorentzian
signature. In this formalism general relativity is describable as a Yang-Mills
gauge theory defined on the (1+1)-dimensional base manifold, whose local gauge
symmetry is the group of the diffeomorphisms of the 2-dimensional fibre
manifold. After presenting the Einstein's field equations in this formalism, I
solve them for spherically symmetric case to obtain the Schwarzschild solution.
Then I discuss possible applications of this formalism.

</DOC>
<DOC>
<DOCNO> 116702 </DOCNO>
Excited states of the hydrogen molecule in magnetic fields: The singlet


  Excited states of the hydrogen molecule subject to a homogeneous magnetic
field are investigated for the parallel configuration in the complete regime of
field strengths B=0-100a.u.. Up to seven excitations are studied for gerade as
well as ungerade spin singlet states of Sigma symmetry with a high accuracy.
The evolution of the potential energy curves for the individual states with
increasing field strength as well as the overall behaviour of the spectrum are
discussed in detail. A variety of phenomena like for example the sequence of
changes for the dissociation channels of excited states and the resulting
formation of outer wells are encountered. Possible applications of the obtained
data to the analysis of magnetic white dwarfs

</DOC>
<DOC>
<DOCNO> 117161 </DOCNO>
Transverse redshift effects without special relativity


  Transverse redshift effects are sometimes presented as being unique to
special relativity (the "transverse Doppler effect"). We argue that if the
detector is aimed at 90 degrees in the laboratory frame, most theories will
predict a redshifted frequency at the detector, although these predictions can
be concealed by specifying that angles should be defined in a frame /other/
than the laboratory frame. These redshifts are often stronger than special
relativity's predictions. We list some of the situations in which
lab-transverse redshifts would be expected.

</DOC>
<DOC>
<DOCNO> 169900 </DOCNO>
Self- and cross-phase modulation of ultrashort light pulses in an


  Quantum theory of self-phase and cross-phase modulation of ultrashort light
pulses in the Kerr medium is developed with taking into account the response
time of an electronic nonlinearity. The correspondent algebra of time-dependent
Bose-operators is elaborated. It is established that the spectral region of the
pulse, where the quadrature fluctuations level is lower than the shot-noise
one, depends on the value of the nonlinear phase shift, the intensity of
another pulse, and the relaxation time of the nonlinearity. It is shown that
the frequency of the pulse spectrum at which the suppression of fluctuations is
maximum can be controlled by adjusting the other pulse intensity.

</DOC>
<DOC>
<DOCNO> 40578 </DOCNO>
Rare Decay Results from KTeV and (rho,eta)_{CKM}


  Rare decay results from KTeV are reviewed, emphasizing modes that in
principle provide information about the CKM matrix. Our recent results in
lepton flavor violating modes are also presented.

</DOC>
<DOC>
<DOCNO> 69147 </DOCNO>
Nucleon structure effect on the longitudinal response function


  Using the quark-meson coupling model, we study the longitudinal response
function for quasielastic electron scattering from nuclear matter within
relativistic RPA. In QMC the coupling constant between the scalar meson and the
nucleon is expected to decrease with increasing nuclear density. Furthermore,
since the electromagnetic form factors of the in-medium nucleon are modified at
the same time, the longitudinal response function and the Coulomb sum are
reduced by a total of about 20% in comparison with the Hartree contribution.

</DOC>
<DOC>
<DOCNO> 118897 </DOCNO>
Deep HST+STIS Color-Magnitude Diagrams of the Dwarf Irregular Galaxy


  We have obtained V and I-band photometry for 1886 stars down to I=27 and V=28
in the field of the dwarf irregular galaxy WLM, using deep STIS CL and LP-band
images taken in the parallel mode with the Hubble Space Telescope. The
photometry is used to study the horizontal branch identified in WLM. The
horizontal branch, extending blueward from the red giant clump, is an
unambiguous signature of an old population. We demonstrate that it is possible
to reach the horizontal branch of an old population at a distance of ~1 Mpc
using STIS, with relatively short exposure times. From the VI color-magnitude
diagram we obtain an accurate distance modulus (m-M)_0 = 24.95 \pm 0.13 for WLM
by using the V-magnitude of the horizontal branch, and by adopting E(V-I)=0.03.
The implications are: 1) WLM formed stars at high redshift, and 2) the old
population of WLM can be representative of a protogalactic fragment, related to
those accreted to form the Milky Way halo.

</DOC>
<DOC>
<DOCNO> 150368 </DOCNO>
Boundary Operators in Quantum Field Theory


  The fundamental laws of physics can be derived from the requirement of
invariance under suitable classes of transformations on the one hand, and from
the need for a well-posed mathematical theory on the other hand. As a part of
this programme, the present paper shows under which conditions the introduction
of pseudo-differential boundary operators in one-loop Euclidean quantum gravity
is compatible both with their invariance under infinitesimal diffeomorphisms
and with the requirement of a strongly elliptic theory. Suitable assumptions on
the kernel of the boundary operator make it therefore possible to overcome
problems resulting from the choice of purely local boundary conditions.

</DOC>
<DOC>
<DOCNO> 151443 </DOCNO>
Consequences of 't Hooft's Equivalence Class Theory and Symmetry by


  According to 't Hooft (Class.Quantum.Grav. 16 (1999), 3263), quantum gravity
can be postulated as a dissipative deterministic system, where quantum states
at the ``atomic scale''can be understood as equivalence classes of primordial
states governed by a dissipative deterministic dynamics law at the ``Planck
scale''. In this paper, it is shown that for a quantum system to have an
underlying deterministic dissipative dynamics, the time variable should be
discrete if the continuity of its temporal evolution is required. Besides, the
underlying deterministic theory also imposes restrictions on the energy
spectrum of the quantum system. It is also found that quantum symmetry at the
``atomic scale'' can be induced from 't Hooft's Coarse Graining classification
of primordial states at the "Planck scale".

</DOC>
<DOC>
<DOCNO> 117686 </DOCNO>
Deductive-reductive determination of the model of our observed Universe


  According to the observations, in our expansive and isotropic relativistic
Universe for the gravitational phenomena in a Newtonian approximation the
Newtonian non-modified relations are valid. The Friedmann general equations of
isotropic and homogeneous universe dynamics describe an infinite number of
models of expansive and isotropic relativistic universe in the Newtonian
approximation, but only in one of them the Newtonian non-modified relations are
valid. These facts give - till now not considered - possibility for unambiguous
deductive-reductive determination of the Friedmannian model, which describes
our observed Universe.

</DOC>
<DOC>
<DOCNO> 12623 </DOCNO>
Spatially homogeneous ground state of the two-dimensional Hubbard model


  We investigate the stability with respect to phase separation or charge
density-wave formation of the two-dimensional Hubbard model for various values
of the local Coulomb repulsion and electron densities using Green-function
Monte Carlo techniques. The well known sign problem is particularly serious in
the relevant region of small hole doping. We show that the difference in
accuracy for different doping makes it very difficult to probe the phase
separation instability using only energy calculations, even in the
weak-coupling limit ($U=4t$) where reliable results are available. By contrast,
the knowledge of the charge correlation functions allows us to provide clear
evidence of a spatially homogeneous ground state up to $U=10t$.

</DOC>
<DOC>
<DOCNO> 102538 </DOCNO>
Coordinate restrictions of linear operators in $l_2^n$


  This paper addresses the problem of improving properties of a linear operator
u in $l_2^n$ by restricting it onto coordinate subspaces. We discuss how to
reduce the norm of u by a random coordinate restriction, how to approximate u
by a random operator with small "coordinate" rank, how to find coordinate
subspaces where u is an isomorphism. The first problem in this list provides a
probabilistic extension of a suppression theorem of Kashin and Tzafriri, the
second one is a new look at a result of Rudelson on the random vectors in the
isotropic position, the last one is the recent generalization of the
Bourgain-Tzafriri's invertibility principle. The main point is that all the
results are independent of n, the situation is instead controlled by the
Hilbert-Schmidt norm of u. As an application, we provide an almost optimal
solution to the problem of harmonic density in harmonic analysis, and a
solution to the reconstruction problem for communication networks which deliver
data with random losses.

</DOC>
<DOC>
<DOCNO> 100839 </DOCNO>
Deforming Stanley-Reisner rings


  Starting with a simplicial complex X, we study the infinitesimal deformation
theory of the associated affine and projective varieties A(X) and P(X),
respectively. These investigations include the calculation of the multigraded
vector spaces T1 and T2, the cup product, and the localization maps. As an
application we obtain certain non-smoothing results in the special case when X
is a combinatorial manifold.

</DOC>
<DOC>
<DOCNO> 122043 </DOCNO>
On the Initial Mass Function of Population III Stars


  The collapse and fragmentation of filamentary primordial gas clouds are
explored using 1D and 2D hydrodynamical simulations coupled with the
nonequilibrium processes of H2 formation. The simulations show that depending
upon the initial density,there are two occasions for the fragmentation of
primordial filaments. If a filament has relatively low initial density, the
radial contraction is slow due to less effective H2 cooling. This filament
tends to fragment into dense clumps before the central density reaches
$10^{8-9}$ cm$^{-3}$, where H2 cooling by three-body reactions is effective and
the fragment mass is more massive than some tens $M_\odot$. In contrast, if a
filament is initially dense, the more effective H2 cooling with the help of
three-body reactions allows the filament to contract up to $n\sim 10^{12}$
cm$^{-3}$. After the density reaches $n\sim 10^{12}$ cm$^{-3}$, the filament
becomes optically thick to H2 lines and the radial contraction subsequently
almost stops. At this final hydrostatic stage, the fragment mass is lowered
down to $\approx 1M_\odot$ because of the high density of the filament. The
dependence of the fragment mass upon the initial density could be translated
into the dependence on the local amplitude of random Gaussian density fields or
the epoch of the collapse of a parent cloud. Hence, it is predicted that the
initial mass function of Population III stars is likely to be bimodal with
peaks of $\approx 10^2 M_\odot$ and $\approx 1M_\odot$, where the relative
heights could be a function of the collapse epoch.

</DOC>
<DOC>
<DOCNO> 85410 </DOCNO>
Inflation and nonequilibrium thermodynamics for the fluctuations in the


  In the framework of inflationary cosmology I study some aspects of
nonequilibrium thermodynamics for the matter field fluctuations. The
thermodynamic analysis is developed for de Sitter and power - law expansions of
the universe. In both cases, I find that the heat capacity is negative leading
respectively, to exponential and superexponential growth for the number of
states in the infrared sector for de Sitter and power-law expansions of the
universe. The spectrum for the matter field fluctuations can be understood from
the background effective temperature when the horizon entry.

</DOC>
<DOC>
<DOCNO> 118561 </DOCNO>
Small Deviations from Gaussianity and The Galaxy Cluster Abundance


  We raise the hypothesis that the density fluctuations field which originates
the growth of large scale structures is a combination of two or more
distributions. By applying the statistical analysis of finite mixture
distributions to a specific combination of Gaussian plus non-Gaussian random
fields, we studied the case where just a small departure from Gaussianity is
allowed. Our results suggest that even a very small level of non-Gaussianity
may introduce significant changes in the cluster abundance evolution rate.

</DOC>
<DOC>
<DOCNO> 71724 </DOCNO>
Quantum effects of compactified AdS_5 geometry on the higgs potential


  In this paper we determine the one loop radiative correction to the higgs
potential due to quantum fluctuations about the background metric of
Randall-Sundrum model. We then examine the effects of the one loop effective
potential on the stability of the classical vacuum paying particular attention
to the tadpole terms which could dominate over the classical potential for
small field configurations. We find that although the one loop potential due to
scale fluctuations could develop a tadpole term in certain regions of the
parameter space, it is positive for either sign of H. The quadratic and quartic
terms in the radiative correction are too small to cause any instability to the
classical vacuum for field configurations that do not violate the limits of
ordinary perturbation theory.

</DOC>
<DOC>
<DOCNO> 39879 </DOCNO>
The CKM phase $\alpha$ through $B \to a_0 \pi$


  We propose the decay modes $B \to a_0 (\to \eta \pi) \pi$ to determine the
CKM phase $\alpha$. One can analyze these modes through (i) the $B \to a_0 \pi$
isospin pentagon, (ii) the time dependent Dalitz plot of $B^0(t) \to a_0^{\pm}
\pi^{\mp} \to \eta \pi^+ \pi^-$, and (iii) the time dependence of $B^0(t) \to
a_0^0 (\to \eta \pi^0) \pi^0$. We show that the $a_0 \pi$ modes have certain
advantages as compared to the $\rho \pi$ modes, and strongly recommend the time
dependent Dalitz plot analysis in the $a_0 \pi$ channel.

</DOC>
<DOC>
<DOCNO> 150828 </DOCNO>
A Stable Non-BPS Configuration From Intersecting Branes and Antibranes


  We describe a tachyon-free stable non-BPS brane configuration in type IIA
string theory. The configuration is an elliptic model involving rotated NS5
branes, D4 branes and anti-D4 branes, and is dual to a fractional
brane-antibrane pair placed at a conifold singularity. This configuration
exhibits an interesting behaviour as we vary the radius of the compact
direction. Below a critical radius the D4 and anti-D4 branes are aligned, but
as the radius increases above the critical value the potential between them
develops a minimum away from zero. This signals a phase transition to a
configuration with finitely separated branes.

</DOC>
<DOC>
<DOCNO> 152337 </DOCNO>
Tunneling of Born-Infeld Strings to D2-Branes


  A Born-Infeld theory describing a D2-brane coupled to a 4-form RR field
strength is considered, and the general solutions of the static and Euclidean
time equations are derived and discussed. The period of the bounce solutions is
shown to allow a consideration of tunneling and quantum-classical transitions
in the sphaleron region. The order of such transitions, depending on the
strength of the RR field strength, is determined. A criterion is then derived
to confirm these findings.

</DOC>
<DOC>
<DOCNO> 118798 </DOCNO>
High Resolution HST-STIS Spectra of CI and CO in the Beta Pictoris


  High resolution FUV echelle spectra showing absorption features arising from
CI and CO gas in the Beta Pictoris circumstellar (CS) disk were obtained on
1997 December 6 and 19 using the Space Telescope Imaging Spectrograph (STIS).
An unsaturated spin-forbidden line of CI at 1613.376 A not previously seen in
spectra of Beta Pictoris was detected, allowing for an improved determination
of the column density of CI at zero velocity relative to the star (the stable
component), N = (2-4) x 10^{16} cm^{-2}. Variable components with multiple
velocities, which are the signatures of infalling bodies in the Beta Pictoris
CS disk, are observed in the CI 1561 A and 1657 A multiplets. Also seen for the
first time were two lines arising from the metastable singlet D level of
carbon, at 1931 A and 1463 A The results of analysis of the CO A-X (0-0),
(1-0), and (2-0) bands are presented, including the bands arising from {13}^CO,
with much better precision than has previously been possible, due to the very
high resolution provided by the STIS echelle gratings. Only stable CO gas is
observed, with a column density N(CO) = (6.3 +/- 0.3) x 10^{14} cm{-2}. An
unusual ratio of the column densities of {12}^CO to {13}^CO is found (R = 15
+/- 2). The large difference between the column densities of CI and CO
indicates that photodissociation of CO is not the primary source of CI gas in
the disk, contrary to previous suggestion.

</DOC>
<DOC>
<DOCNO> 12582 </DOCNO>
Supersonic and multiple topological excitations in the driven


  The criteria for the existence of supersonic and multiple topological
excitations (kinks) in the driven Frenkel-Kontorova model (a chain of atoms
placed into an external periodic potential) with anharmonic (exponential)
interatomic interactions are studied.

</DOC>
<DOC>
<DOCNO> 40536 </DOCNO>
New FOCUS results on charm mixing and CP violation


  We present a summary of recent results on CP violation and mixing in the
charm quark sector based on a high statistics sample collected by
photoproduction experiment FOCUS (E831 at Fermilab). We have measured the
difference in lifetimes for the $D^0$ decays: $D^0 \to K^-\pi^+$ and $D^0 \to
K^-K^+$. This translates into a measurement of the $y_{CP}$ mixing parameter in
the $\d0d0$ system, under the assumptions that $K^-K^+$ is an equal mixture of
CP odd and CP even eigenstates, and CP violation is negligible in the neutral
charm meson system. We verified the latter assumption by searching for a CP
violating asymmetry in the Cabibbo suppressed decay modes $D^+ \to
K^-K^+\pi^+$, $D^0 \to K^-K^+$ and $D^0 \to \pi^-\pi^+$. We show preliminary
results on a measurement of the branching ratio $\Gamma(D^{*+}\to \pi^+
(K^+\pi^-))/\Gamma(D^{*+}\to \pi^+ (K^-\pi^+))$.

</DOC>
<DOC>
<DOCNO> 69475 </DOCNO>
Improved Conformal Mapping of the Borel Plane


  The conformal mapping of the Borel plane can be utilized for the analytic
continuation of the Borel transform to the entire positive real semi-axis and
is thus helpful in the resummation of divergent perturbation series in quantum
field theory. We observe that the rate of convergence can be improved by the
application of Pad\'{e} approximants to the Borel transform expressed as a
function of the conformal variable, i.e. by a combination of the analytic
continuation via conformal mapping and a subsequent numerical approximation by
rational approximants. The method is primarily useful in those cases where the
leading (but not sub-leading) large-order asymptotics of the perturbative
coefficients are known.

</DOC>
<DOC>
<DOCNO> 13039 </DOCNO>
Large Orbital Magnetic Moment in Feo, Fes and Febr2


  Magnetic moment of the Fe2+ ion in FeO, FeS and FeBr2 has been calculated
within the quantum atomistic solid-state theory to substantially exceed a value
of 4 muB in the magnetically-ordered state at 0 K. In all compounds the large
orbital moment, of 0.7 - 1.1 muB, has been revealed. Our calculations show that
for the meaningful analysis of electronic and magnetic properties of FeO, FeS
and FeBr2 the intra-atomic spin-orbit coupling is essentially important and
that the orbital moment is largely unquenched in 3d- ion containing compounds.

</DOC>
<DOC>
<DOCNO> 68119 </DOCNO>
Matter induced $\rho$-$\delta$ mixing : a source of dileptons


  We study the possibility of $\rho-\delta$ mixing via N-N excitations in dense
nuclear matter. This mixing induces a peak in the dilepton spectra at an
invariant mass equal to that of the $\delta$. We calculate the cross section
for dilepton production through the mixing process and we compare its size with
that of $\pi-\pi$ annihilation. In-medium masses and mixing angles are also
calculated.

</DOC>
<DOC>
<DOCNO> 12125 </DOCNO>
Landau-Khalatnikov two-fluid hydrodynamics of a trapped Bose gas


  Starting from the quantum kinetic equation for the non-condensate atoms and
the generalized Gross-Pitaevskii equation for the condensate, we derive the
two-fluid hydrodynamic equations of a trapped Bose gas at finite temperatures.
We follow the standard Chapman-Enskog procedure, starting from a solution of
the kinetic equation corresponding to the complete local equilibrium between
the condensate and the non-condensate components. Our hydrodynamic equations
are shown to reduce to a form identical to the well-known Landau-Khalatnikov
two-fluid equations, with hydrodynamic damping due to the deviation from local
equilibrium. The deviation from local equilibrium within the thermal cloud
gives rise to dissipation associated with shear viscosity and thermal
conduction. In addition, we show that effects due to the deviation from the
diffusive local equilibrium between the condensate and the non-condensate
(recently considered by Zaremba, Nikuni and Griffin) can be described by four
frequency-dependent second viscosity transport coefficients. We also derive
explicit formulas for all the transport coefficients. These results are used to
introduce two new characteristic relaxation times associated with hydrodynamic
damping. These relaxation times give the rate at which local equilibrium is
reached and hence determine whether one is in the two-fluid hydrodynamic
region.

</DOC>
<DOC>
<DOCNO> 7977 </DOCNO>
Intrinsic c-Axis Transport in 2212-BSCCO


  We describe two experimental approaches to circumvent the problem of
self-heating in IV measurements on small mesa samples of 2212-BSCCO.
Simultaneous dc and temperature measurements have been performed, allowing
corrections for heating to be made. Short pulse measurements have also been
made, where the IV characteristics and the mesa temperature can be measured on
a $\mu $s time-scale enabling intrinsic IV characteristics to be derived, even
in the presence of appreciable self-heating. Self-heating leads to an
appreciable depression of the apparent energy gap and also accounts, in major
part, for the s-shaped characteristics often reported at high currents. By
correcting for the temperature rise, we derive the intrinsic temperature
dependence of the tunnelling characteristics for crystals with a range of
doping. Results are compared with recent theoretical models for c-axis
transport in d-wave superconductors.

</DOC>
<DOC>
<DOCNO> 40088 </DOCNO>
A study of the centrally produced eta pi0 and eta pi- systems in pp


  A partial wave analysis of the centrally produced eta pi0 and eta pi-
channels has been performed in pp collisions using an incident beam momentum of
450 GeV/c. Clear a0(980) and a2(1320) signals have been observed in S and D+
waves respectively. The dPT, phi and |t| distributions of these resonances are
presented.

</DOC>
<DOC>
<DOCNO> 101132 </DOCNO>
Geometry of the smooth dual of GL(n)


  Let A(n) be the smooth dual of the p-adic group G=GL(n). We create on A(n)
the structure of a complex algebraic variety. There is a morphism of A(n) onto
the Bernstein variety Omega G which is injective on each component of A(n). The
tempered dual of G is a deformation retract of A(n). The periodic cyclic
homology of the Hecke algebra of G is isomorphic to the periodised de Rham
cohomology supported on finitely many components of A(n).

</DOC>
<DOC>
<DOCNO> 152329 </DOCNO>
The correlation function in two dimensional Ising model on the finite


  The correlation function of two dimensional Ising model with the nearest
neighbours interaction on the finite size lattice with the periodical boundary
conditions is derived. The expressions similar to the form factor
representation are obtained both for the ferromagnetic and paramagnetic regions
of coupling constant. The peculiarities caused by the finite size of the system
are discussed. The asymptotic behaviour of the corresponding quantities as
functions of size is calculated. Some generalization of the obtained result is
conjectured.

</DOC>
<DOC>
<DOCNO> 119227 </DOCNO>
The Enrichment History of the Intergalactic Medium: Measuring the CIV/HI


  We have obtained an exceptionally high S/N, high resolution spectrum of the
gravitationally lensed quasar Q1422+231 in order to investigate the metal
enrichment of the IGM. A column density distribution function (CDDF) is
determined for CIV, which is well fit by a power law with index 1.44 +/- 0.05.
Once a correction for incompleteness is applied, we find that the CDDF is
consistent with a power law down to log N(CIV) = 11.75, a factor of 10 more
sensitive than previously determined. In order to determine whether the CIV
enrichment extends to even lower column density HI clouds, we find that an
analysis of individual pixel optical depths is more robust than the stacking
technique. The results obtained from this optical depth method are compared
with analyses of simulated spectra enriched with varying CIV enrichment
recipes. From these simulations, we conclude that more CIV than is currently
directly detected in Q1422+231 is required to reproduce the optical depths
determined from the data, consistent with the conclusions drawn from
consideration of the power law distribution. (Abridged)

</DOC>
<DOC>
<DOCNO> 12177 </DOCNO>
Large-scale low-energy excitations in 3-d spin glasses


  We numerically extract large-scale excitations above the ground state in the
3-dimensional Edwards-Anderson spin glass with Gaussian couplings. We find that
associated energies are O(1), in agreement with the mean field picture. Of
further interest are the position-space properties of these excitations. First,
our study of their topological properties show that the majority of the
large-scale excitations are sponge-like. Second, when probing their geometrical
properties, we find that the excitations coarsen when the system size is
increased. We conclude that either finite size effects are very large even when
the spin overlap q is close to zero, or the mean field picture of homogeneous
excitations has to be modified.

</DOC>
<DOC>
<DOCNO> 9256 </DOCNO>
Form Factors of the Homogeneous Sine-Gordon models


  We provide general determinant formulae for all n-particle form factors
related to the trace of the energy momentum tensor and the analogue of the
order and disorder operator in the $SU(3)_2$-homogeneous Sine-Gordon model. We
employ the form factors related to the trace of the energy momentum tensor in
the application of the c-theorem and find perfect agreement with the physical
picture recently obtained by means of the thermodynamic Bethe ansatz. For
finite resonance parameter we recover the expected WZNW-coset central charge
and for infinite resonance parameter the theory decouples into two free
fermions.

</DOC>
<DOC>
<DOCNO> 119848 </DOCNO>
Constraints on the Space Density of Extragalactic HVCs


  High Velocity Clouds (HVCs) have recently attracted renewed attention as
being long lived, massive dark matter dominated clouds of primordial
composition distributed throughout the Local Group. In this picture the HVCs
would contain a few times 10^7 M_sun of HI and would be at distances of a few
hundred kpc to 1.5 Mpc from the Local Group barycenter. If this extragalactic
interpretation of HVCs is true, similar clouds are expected in other galaxy
groups and around galaxies. We discuss the limits blind HI surveys and QSO
absorption line studies put on this proposed population of clouds.

</DOC>
<DOC>
<DOCNO> 83435 </DOCNO>
Proceedings of the Fourth International Workshop on Automated Debugging


  Over the past decades automated debugging has seen major achievements.
However, as debugging is by necessity attached to particular programming
paradigms, the results are scattered. The aims of the workshop are to gather
common themes and solutions across programming communities, and to
cross-fertilize ideas. AADEBUG 2000 in Munich follows AADEBUG'93 in Linkoeping,
Sweden; AADEBUG'95 in Saint Malo, France; AADEBUG'97 in Linkoeping, Sweden.

</DOC>
<DOC>
<DOCNO> 119663 </DOCNO>
Near-infrared imaging polarimetry of the GG Tau circumbinary ring


  We present 1 micron Hubble Space Telescope/NICMOS resolved imaging
polarimetry of the GG Tau circumbinary ring. We find that the ring displays
east-west asymmetries in surface brightness as well as several pronounced
irregularities, but is smoother than suggested by ground-based adaptive optics
observations. The data are consistent with a 37 deg system inclination and a
projected rotational axis at a position angle of 7 deg east of north,
determined from millimeter imaging. The ring is strongly polarized, up to 50%,
which is indicative of Rayleigh-like scattering from sub-micron dust grains.
Although the polarization pattern is broadly centrosymmetric and clearly
results from illumination of the ring by the central stars, departures from
true centrosymmetry and the irregular flux suggest that binary illumination,
scattering through unresolved circumstellar disks, and shading by these disks,
may all be factors influencing the observed morphology. We confirm a 0.25
arcsec shift between the inner edges of the NIR and millimeter images and find
that the global morphology of the ring and the polarimetry provide strong
evidence for a geometrically thick ring. A simple Monte Carlo scattering
simulation is presented which reproduces these features and supports the thick
ring hypothesis. We cannot confirm filamentary streaming from the binary to the
ring, also observed in the ground-based images, although it is possible that
there is material inside the dynamically cleared region which might ontribute
to filamentary deconvolution artifacts. Finally, we find a faint 5th point
source in the GG Tau field which, if it is associated with the system, is
almost certainly a brown dwarf.

</DOC>
<DOC>
<DOCNO> 121225 </DOCNO>
A Critical Examination of Hypernova Remnant Candidates in M101. I. MF83


  The SNR candidate MF83 in M101 is coincident with a very luminous X-ray
source. Based on the high X-ray luminosity, it has been suggested that MF83 is
a "hypernova remnant" requiring an explosion energy about two orders of
magnitude higher than normal supernovae. We have analyzed high-quality
ground-based and HST observations of MF83, and find that MF83 is a star
formation region, consisting of a large ionized gas shell and four HII regions
along its periphery. Continuum images show OB associations in these HII regions
and within the large shell. The shell has an expansion velocity of $\sim$50
km/s and a diameter of $\sim$270 pc. The optical properties of this shell in
MF83 are similar to those of X-ray-bright superbubbles in the Large Magellanic
Cloud. If the X-ray emission is indeed diffuse, the implied thermal energy in
MF83 is high, a few $\times10^{52}$ ergs. This amount of thermal energy
requires a large number of concentrated supernova explosions or one powerful
explosion. Future X-ray observations with a high angular resolution are needed
to resolve the diffuse emission and point sources in MF83, in order to
determine more accurately the thermal energy in the shell interior and its
required explosion energy.

</DOC>
<DOC>
<DOCNO> 69883 </DOCNO>
Collective Modes in Neutrino `Beam' Electron-Positron Plasma


  We derive semiclassical neutrino-electron transport equations in the
collisionless (Vlasov) limit from the coupled Dirac equations, incorporating
the charged and neutral weak current-current as well as electromagnetic
interactions. A corresponding linear response theory is derived. In particular,
we calculate the response functions for a variety of beam-plasma geometries,
which are of interest in a supernova scenario. We apply this to the study of
plasmons and to a new class of collective {\it pharon} resonance modes, which
are characterized by $\omega < q$. We find that the growth rates of the
unstable modes correspond to a strongly temperature ($\propto T_\nu^2T_e^3$)
and linearly momentum dependent e-folding length of about $10^{10}$ km under
typical conditions for Type II supernovae. This appears to rule out such
long-wavelength collective modes as an efficient means of depositing neutrino
energy into the plasma sphere.

</DOC>
<DOC>
<DOCNO> 102432 </DOCNO>
On multiplicities of points on Schubert varieties in Grassmannians


  We answer some questions related to multiplicity formulas by Rosenthal and
Zelevinsky and by Lakshmibai and Weyman for points on Schubert varieties in
Grassmannians. In particular, we give combinatorial interpretations in terms of
nonintersecting lattice paths of these formulas, which makes the equality of
the two formulas immediately obvious. Furthermore we provide an alternative
determinantal formula for these multiplicities, and we show that they count
semistandard tableaux of unusual shapes.

</DOC>
<DOC>
<DOCNO> 100619 </DOCNO>
Intrinsic geometry of convex ideal polyhedra in hyperbolic 3-space


  The main result is that every complete finite area hyperbolic metric on a
sphere with punctures can be uniquely realized as the induced metric on the
surface of a convex ideal polyhedron in hyperbolic 3-space. A number of other
observations are included.

</DOC>
<DOC>
<DOCNO> 102300 </DOCNO>
On algebraic fiber spaces over varieties of maximal Albanese dimension


  We study algebraic fiber spaces $f:X \longrightarrow Y$ where $Y$ is of
maximal Albanese dimension. In particular we give an effective version a
theorem of Kawamata: If $P_m(X)=1$ for some $m \ge 2$, then the Albanese map of
$X$ is surjective. Combining this with \cite{CH} it follows that $X$ is
birational to an abelian variety if and only if $P_2(X)=1$ and $q(X)= \text{\rm
dim} (X)$.

</DOC>
<DOC>
<DOCNO> 101321 </DOCNO>
Some identities for determinants of structured matrices


  In this paper we establish several relations between the determinants of the
following structured matrices: Hankel matrices, symmetric Toeplitz + Hankel
matrices and Toeplitz matrices. Using known results for the asymptotic behavior
of Toeplitz determinants, these identities are used in order to obtain
Fisher-Hartwig type results on the asymptotics of certain skewsymmetric
Toeplitz determinants and certain Hankel determinants.

</DOC>
<DOC>
<DOCNO> 101369 </DOCNO>
Geometric phase related to point-interaction transport on a magnetic


  We consider a charged quantum particle living in the Lobachevsky plane and
interacting with a homogeneous magnetic field perpendicular to the plane and a
point interaction which is transported adiabatically along a closed loop C in
the plane. We show that the bound-state eigenfunction acquires at that the
Berry phase equal to 2\pi times the number of the flux quanta through the area
encircled by C.

</DOC>
<DOC>
<DOCNO> 122173 </DOCNO>
Multi-color Classification in the Calar Alto Deep Imaging Survey


  We use a multi-color classification method introduced by Wolf, Meisenheimer &
Roeser (2000) to reliably identify stars, galaxies and quasars in the up to
16-dimensional color space provided by the filter set of the Calar Alto Deep
Imaging Survey (CADIS). The samples of stars, galaxies and quasars obtained
this way have been used for dedicated studies published in separate papers. The
classification is good enough to detect quasars rather completely and
efficiently without confirmative spectroscopy. The multi-color redshifts are
accurate enough for most statistical applications, e.g. evolutionary studies of
the galaxy luminosity function. We characterize our current dataset on the
CADIS 1h-, 9h- and 16h-fields. Using Monte-Carlo simulations we model the
classification performance expected for CADIS. We present a summary of the
classification results and discuss unclassified objects. More than 99% of the
whole catalog sample at R<22 (more than 95% at R<23) are successfully
classified matching the expectations derived from the simulations. A small
number of peculiar objects challenging the classification are discussed in
detail. Spectroscopic observations are used to check the reliability of the
multi-color classification (6 mistakes among 151 objects with R<24). We also
determine the accuracy of the multi-color redshifts which are rather good for
galaxies (sigma_z = 0.03) and useful for quasars. We find the classification
performance derived from the simulations to compare well with results from the
real survey. Finally, we locate areas for potential improvement of the
classification.

</DOC>
<DOC>
<DOCNO> 8657 </DOCNO>
Towards artificial muscles


  Solid state actuators (piezoelectric, ferroelectric, ...) deform under an
external field, and have found many applications. They respond fast, but their
mechanical deformations are very small. There is a need for soft actuators,
giving larger responses, but necessarily less fast. This paper describes the
early attempts by Katchalsky and others, and the problems which showed up
-related to time constants, and, most importantly, to fatigue. Two current
attempts are reviewed.

</DOC>
<DOC>
<DOCNO> 102581 </DOCNO>
Covariant geometric quantization of non-relativistic Hamiltonian


  We provide geometric quantization of the vertical cotangent bundle V^*Q
equipped with the canonical Poisson structure. This is a momentum phase space
of non-relativistic mechanics with the configuration bundle Q -> R. The goal is
the Schrodinger representation of V^*Q. We show that this quantization is
equivalent to the fibrewise quantization of symplectic fibres of V^*Q -> R,
that makes the quantum algebra of non-relativistic mechanics an instantwise
algebra. Quantization of the classical evolution equation defines a connection
on this instantwise algebra, which provides quantum evolution in
non-relativistic mechanics as a parallel transport along time.

</DOC>
<DOC>
<DOCNO> 178692 </DOCNO>
Classifying Reported and "Missing" Resonances According to Their P and C


  The Hilbert space H^3q of the three quarks with one excited quark is
decomposed into Lorentz group representations. It is shown that the quantum
numbers of the reported and ``missing'' resonances fall apart and populate
distinct representations that differ by their parity or/and charge conjugation
properties. In this way, reported and ``missing'' resonances become
distinguishable. For example, resonances from the full listing reported by the
Particle Data Group are accommodated by Rarita-Schwinger (RS) type
representations (k/2,k/2)*[(1/2,0)+(0,1/2)] with k=1,3, and 5, the highest spin
states being J=3/2^-, 7/2^+, and 11/2^+, respectively. In contrast to this,
most of the ``missing'' resonances fall into the opposite parity RS fields of
highest-spins 5/2^-, 5/2^+, and 9/2^+, respectively. Rarita-Schwinger fields
with physical resonances as lower-spin components can be treated as a whole
without imposing auxiliary conditions on them. Such fields do not suffer the
Velo-Zwanziger problem but propagate causally in the presence of
electromagnetic fields. The pathologies associated with RS fields arise
basically because of the attempt to use them to describe isolated spin-J=k+1/ 2
states, rather than multispin-parity clusters. The positions of the observed RS
clusters and their spacing are well explained trough the interplay between the
rotational-like (k/2)(k/2 +1)-rule and a Balmer-like -(k+1)^{-2}-behavior.

</DOC>
<DOC>
<DOCNO> 9115 </DOCNO>
Punctured polygons and polyominoes on the square lattice


  We use the finite lattice method to count the number of punctured staircase
and self-avoiding polygons with up to three holes on the square lattice. New or
radically extended series have been derived for both the perimeter and area
generating functions. We show that the critical point is unchanged by a finite
number of punctures, and that the critical exponent increases by a fixed amount
for each puncture. The increase is 1.5 per puncture when enumerating by
perimeter and 1.0 when enumerating by area. A refined estimate of the
connective constant for polygons by area is given. A similar set of results is
obtained for finitely punctured polyominoes. The exponent increase is proved to
be 1.0 per puncture for polyominoes.

</DOC>
<DOC>
<DOCNO> 69381 </DOCNO>
A differential equation approach for examining the subtraction schemes


  We propose a natural differential equation with respect to mass(es) to
analyze the scheme dependence problem. It is shown that the vertex functions
subtracted at an arbitrary Euclidean momentum (MOM) do not satisfy such
differential equations, as extra unphysical mass dependence is introduced which
is shown to lead to the violation of the canonical form of the Slavnov-Taylor
identities, a notorious fact with MOM schemes. By the way, the traditional
advantage of MOM schemes in decoupling issue is shown to be lost in the context
of Callan-Symanzik equations.

</DOC>
<DOC>
<DOCNO> 102095 </DOCNO>
The intersection of opposed big cells in the real flag variety of type


  We compute the Euler characteristics of the individual connected components
of the intersection of two opposed big cells in the real flag variety of type
$G_2$, verifying a conjecture of Rietsch.

</DOC>
<DOC>
<DOCNO> 12869 </DOCNO>
Decoupling the SU(N)_2-homogeneous Sine-Gordon model


  We provide a systematic construction for all n-particle form factors of the
SU(N)_2/U(1)^{N-1}-homogeneous Sine-Gordon model in terms of general
determinant formulae for a huge class of local operators. The ultraviolet limit
is carried out and the corresponding Virasoro central charge together with the
conformal dimensions of various operators are identified. The renormalization
group flow is studied and we find a precise rule, depending on the relative
order of magnitude of the resonance parameters, according to which the theory
decouples into new cosets along the flow.

</DOC>
<DOC>
<DOCNO> 122205 </DOCNO>
Super-horizon perturbations and preheating


  We discuss the evolution of linear perturbations about a
Friedmann-Robertson-Walker background metric, using only the local conservation
of energy-momentum. We show that on sufficiently large scales the curvature
perturbation on spatial hypersurfaces of uniform-density is constant when the
non-adiabatic pressure perturbation is negligible. We clarify the conditions
under which super-horizon curvature perturbations may vary, using preheating as
an example.

</DOC>
<DOC>
<DOCNO> 9182 </DOCNO>
Statistical Model of Superconductivity in a 2D Binary Boson-Fermion


  A two-dimensional (2D) assembly of noninteracting, temperature-dependent,
composite-boson Cooper pairs (CPs) in chemical and thermal equilibrium with
unpaired fermions is examined in a binary boson-fermion statistical model as
the superconducting singularity temperature is approached from above. The model
is derived from {\it first principles} for the BCS model interfermion
interaction from three extrema of the system Helmholtz free energy (subject to
constant pairable-fermion number) with respect to: a) the pairable-fermion
distribution function; b) the number of excited (bosonic) CPs, i.e., with
nonzero total momenta---usually ignored in BCS theory---and with the
appropriate (linear, as opposed to quadratic) dispersion relation that arises
from the Fermi sea; and c) the number of CPs with zero total momenta. Compared
with the BCS theory condensate, higher singularity temperatures for the
Bose-Einstein condensate are obtained in the binary boson-fermion mixture model
which are in rough agreement with empirical critical temperatures for quasi-2D
superconductors

</DOC>
<DOC>
<DOCNO> 178729 </DOCNO>
Nuclear Transparency in Heavy Ion Collisions at 14.6 GeV/nucleon


  The probability of a projectile nucleon to traverse a target nucleus without
interaction is calculated for central Si-Pb collisions and compared to the data
of E814. The calculations are performed in two independent ways, via Glauber
theory and using the transport code UrQMD. For central collisions Glauber
predictions are about 30 to 50% higher than experiment, while the output of
UrQMD does not show the experimental peak of beam rapidity particles.

</DOC>
<DOC>
<DOCNO> 68194 </DOCNO>
Model of Large Mixing Angle MSW Solution


  We have obtained the neutrino mass matrix with the large mixing angle (LMA)
MSW solution,
 $\sin^2 2\th_\odot=0.65\sim 0.97$ and $\Delta m_{\odot}^2= 10^{-5}\sim
10^{-4}\eV^2$, in the $S_{3L}\times S_{3R}$ flavor symmetry. The structure of
our neutrino mass matrix is found to be stable against radiative corrections.

</DOC>
<DOC>
<DOCNO> 118944 </DOCNO>
Observations of the supernova remnant W28 at TeV energies


  The atmospheric Cerenkov imaging technique has been used to search for
point-like and diffuse TeV gamma-ray emission from the southern supernova
remnant, W28, and surrounding region. The search, made with the CANGAROO 3.8m
telescope, encompasses a number of interesting features, the supernova remnant
itself, the EGRET source 3EG J1800-2338, the pulsar PSR J1801-23, strong 1720
MHz OH masers and molecular clouds on the north and east boundaries of the
remnant. An analysis tailored to extended and off-axis point sources was used,
and no evidence for TeV gamma-ray emission from any of the features described
above was found in data taken over the 1994 and 1995 seasons. Our upper limit
(E>1.5 TeV) for a diffuse source of radius 0.25deg encompassing both molecular
clouds was calculated at 6.64e-12 photons cm^-2 s^-1 (from 1994 data), and
interpreted within the framework of a model predicting TeV gamma-rays from
shocked-accelerated hadrons. Our upper limit suggests the need for some cutoff
in the parent spectrum of accelerated hadrons and/or slightly steeper parent
spectra than that used here (-2.1). As to the nature of 3EG J1800-2338, it
possibly does not result entirely from pi-zero decay, a conclusion also
consistent with its location in relation to W28.

</DOC>
<DOC>
<DOCNO> 117838 </DOCNO>
The rise and fall of V4334 Sgr (Sakurai's Object)


  CCD UBVRi photometry of the final helium flash object V4334 Sgr (Sakurai's
Object), carried out during 1997 - 1999, is presented, and the light curve from
its pre-discovery rise to the dust obscuration phase is constructed. The
optical light curve can be divided into four sections, the rise to maximum, the
maximum, the dust onset, and the massive dust shell phase. The color indices
show a general increase with time, first because of the photospheric expansion
and cooling, and later because of the dust forming events. The energy
distributions for the years 1996 - 1999 show that an increasing part of the
energy is radiated at infrared wavelengths. In 1996, the infrared excess is
likely caused by free-free radiation in the stellar wind. Starting from 1997 or
1998 at the latest, carbon dust grains are responsible for the more and more
dramatic decrease of optical radiation and the growing infrared excess. Its
photometric behavior in 1998 - 1999 mimics the ``red declines'' of R CrB
variables, the amplitude, however, is more extreme than any fading ever
observed in an R CrB star. Evidence is given that a complete dust shell has
formed around V4334 Sgr. It therefore shows similarities with dust-forming
classical novae, although evolving ~20 times more slowly. Its luminosity
increased by a factor 4 between 1996 and 1998. A comparison of time scales of
the final helium flash objects FG Sge, V605 Aql and V4334 Sgr shows that the
observed photometric and spectroscopic features are similar, while V4334 Sgr is
the most rapidly evolving object to date.

</DOC>
<DOC>
<DOCNO> 11121 </DOCNO>
Direct calculation of the hard-sphere crystal/melt interfacial free


  We present a direct calculation by molecular-dynamics computer simulation of
the crystal/melt interfacial free energy, $\gamma$, for a system of hard
spheres of diameter $\sigma$. The calculation is performed by thermodynamic
integration along a reversible path defined by cleaving, using specially
constructed movable hard-sphere walls, separate bulk crystal and fluid systems,
which are then merged to form an interface. We find the interfacial free energy
to be slightly anisotropic with $\gamma$ = 0.62$\pm 0.01$, 0.64$\pm 0.01$ and
0.58$\pm 0.01 k_BT/\sigma^2$ for the (100), (110) and (111) fcc crystal/fluid
interfaces, respectively. These values are consistent with earlier density
functional calculations and recent experiments measuring the crystal nucleation
rates from colloidal fluids of polystyrene spheres that have been interpreted
[Marr and Gast, Langmuir {\bf 10}, 1348 (1994)] to give an estimate of $\gamma$
for the hard-sphere system of $0.55 \pm 0.02 k_BT/\sigma^2$, slightly lower
than the directly determined value reported here.

</DOC>
<DOC>
<DOCNO> 13544 </DOCNO>
Small Angle Scattering data analysis for dense polydisperse systems: the


  FLAC is a program to calculate the small-angle neutron scattering intensity
of highly packed polydisperse systems of neutral or charged hard spheres within
the Percus-Yevick and the Mean Spherical Approximation closures, respectively.
The polydisperse system is defined by a size distribution function and the
macro-particles have hard sphere radii which may differ from the size of their
scattering cores. With FLAC, one can either simulate scattering intensities or
fit experimental small angle neutron scattering data. In output scattering
intensities, structure factors and pair correlation functions are provided.
Smearing effects due to instrumental resolution, vertical slit, primary beam
width and multiple scattering effects are also included on the basis of the
existing theories. Possible form factors are those of filled or two-shell
spheres.

</DOC>
<DOC>
<DOCNO> 8036 </DOCNO>
Evolution of reference networks with aging


  We study the growth of a reference network with aging of sites defined in the
following way. Each new site of the network is connected to some old site with
probability proportional (i) to the connectivity of the old site as in the
Barab\'{a}si-Albert's model and (ii) to $\tau^{-\alpha}$, where $\tau$ is the
age of the old site. We consider $\alpha$ of any sign although reasonable
values are $0 \leq \alpha \leq \infty$. We find both from simulation and
analytically that the network shows scaling behavior only in the region $\alpha
< 1$. When $\alpha$ increases from $-\infty$ to 0, the exponent $\gamma$ of the
distribution of connectivities ($P(k) \propto k^{-\gamma}$ for large $k$) grows
from 2 to the value for the network without aging, i.e. to 3 for the
Barab\'{a}si-Albert's model. The following increase of $\alpha$ to 1 makes
$\gamma$ to grow to $\infty$. For $\alpha>1$ the distribution $P(k)$ is
exponentional, and the network has a chain structure.

</DOC>
<DOC>
<DOCNO> 11164 </DOCNO>
Comment on ``Composite Fermion Hofstadter Problem: Partially Polarized


  In a recent paper [Phys.Rev.Lett. 82, 3665 (1999)], magnetic field driven
spin transitions in fractional quantum Hall (FQH) states were reported, and in
particular, at filling factors 2/3 and 2/5, weak features were observed at half
polarization. This would imply that the ground state energy is non-monotonic at
half polarization. It was proposed in
 Ref.[Phys. Rev. Lett. 84, 350 (2000)] that the system is then a charge density
wave (CDW) state of composite fermions with a subband gap that could explain
the observed plateaus at half polarization. Similar CDW state is also expected
at filling factor 2/3. Here we show that the proposed CDW state is not the half
polirized ground state at these two filling factors.

</DOC>
<DOC>
<DOCNO> 152148 </DOCNO>
Giant Gravitons from Holomorphic Surfaces


  We introduce a class of supersymmetric cycles in spacetimes of the form AdS
times a sphere or $T^{1,1}$ which can be considered as generalizations of the
giant gravitons. Branes wrapped on these cycles preserve $1\over 2$, $1\over 4$
or $1\over 8$ of the supersymmetry. On the CFT side these configurations
correspond to superpositions of the large number of BPS states.

</DOC>
<DOC>
<DOCNO> 40128 </DOCNO>
Search for light-to-heavy quark flavor changing neutral currents in $\nu


  We report on a search for flavor-changing neutral-currents (FCNC) in the
production of heavy quarks in deep inelastic $\nu_{\mu}N$ and $\bar{\nu}%
_{\mu}N$ scattering by the NuTeV experiment at the Fermilab Tevatron. This
measurement, made possible by the high-purity NuTeV sign-selected beams, probes
for FCNC in heavy flavors at the quark level and is uniquely sensitive to
neutrino couplings of potential FCNC mediators. All searches are consistent
with zero, and limits on the effective mixing strengths $% | V_{uc}| ^{2}$, $|
V_{db}| ^{2}$, and $| V_{sb}| ^{2}$ are obtained.

</DOC>
<DOC>
<DOCNO> 84154 </DOCNO>
Stochastic semiclassical fluctuations in Minkowski spacetime


  The semiclassical Einstein-Langevin equations which describe the dynamics of
stochastic perturbations of the metric induced by quantum stress-energy
fluctuations of matter fields in a given state are considered on the background
of the ground state of semiclassical gravity, namely, Minkowski spacetime and a
scalar field in its vacuum state. The relevant equations are explicitly derived
for massless and massive fields arbitrarily coupled to the curvature. In doing
so, some semiclassical results, such as the expectation value of the
stress-energy tensor to linear order in the metric perturbations and particle
creation effects, are obtained. We then solve the equations and compute the
two-point correlation functions for the linearized Einstein tensor and for the
metric perturbations. In the conformal field case, explicit results are
obtained. These results hint that gravitational fluctuations in stochastic
semiclassical gravity have a ``non-perturbative'' behavior in some
characteristic correlation lengths.

</DOC>
<DOC>
<DOCNO> 10604 </DOCNO>
Anomalous peak in the superconducting condensate density of cuprate high


  The doping dependence of the superconducting condensate density, n_{s}^{o},
has been studied by muon-spin-rotation for
Y_{0.8}Ca_{0.2}Ba_{2}(Cu_{1-z}Zn_{z})_{3}O_{7-\delta} and
Tl_{0.5-y}Pb_{0.5+y}Sr_{2}Ca_{1-x}Y_{x}Cu_{2}O_{7}. We find that n_{s}^{o}
exhibits a pronounced peak at a unique doping state in the slightly overdoped
regime. Its position coincides with the critical doping state where the normal
state pseudogap first appears depleting the electronic density of states. A
surprising correlation between n_{s}^{o} and the condensation energy U_{o} is
observed which suggests unconventional behavior even in the overdoped region.

</DOC>
<DOC>
<DOCNO> 116846 </DOCNO>
Design of a 3 GHz Accelerator Structure for the CLIC Test Facility (CTF


  For the CLIC two-beam scheme, a high-current, long-pulse drive beam is
required for RF power generation. Taking advantage of the 3 GHz klystrons
available at the LEP injector once LEP stops, a 180 MeV electron accelerator is
being constructed for a nominal beam current of 3.5 A and 1.5 microsecond pulse
length. The high current requires highly effective suppression of dipolar
wakes. Two concepts are investigated for the accelerating structure design: the
"Tapered Damped Structure" developed for the CLIC main beam, and the "Slotted
Iris - Constant Aperture" structure. Both use 4 SiC loads per cell for
effective higher-order mode damping. A full-size prototype of the TDS structure
has been built and tested successfully at full power. A first prototype of the
SICA structure is being built.

</DOC>
<DOC>
<DOCNO> 100115 </DOCNO>
An Infinite Suite of Links-Gould Invariants


  This paper describes a method to obtain state model parameters for an
infinite series of Links-Gould link invariants LG^{m,n}, based on quantum R
matrices associated with the (\dot{0}_m | \dot{\alpha}_n) representations of
the quantum superalgebras U_q[gl(m|n)]. Explicit details of the state models
for the cases n=1 and m=1,2,3,4 are supplied. Some evaluations of the new link
invariants are provided, as are some of their gross properties.

</DOC>
<DOC>
<DOCNO> 122778 </DOCNO>
Anomalous Surface Brightness Fluctuations in NGC 4489


  Anomalously high K-band surface brightness fluctuations (SBF) have been
reported in NGC 4489 by Pahre & Mould (1994), Jensen et al. (1996) and Jensen
et al. (1998). However, these conclusions were uncertain because of relatively
low signal-to-noise data. New high signal-to-noise data for NGC 4489 have been
obtained at the NOAO/KPNO 2.1m and the ESO/La Silla 3.5m NTT telescopes.
Adopting the I-band SBF distance modulus determined by Tonry et al. (1990) and
the M_I versus (V-I) calibration of Tonry et al. (2000), a value of M_K =-6.18
+/-0.09 mag was derived. Relative to the average empirical M_K derived for
giant ellipticals by Jensen et al. (1998) (M_K=-5.61 +/- 0.12 mag), the
detection of an anomalous K-band SBF in NGC 4489 is confirmed at the two sigma
level. Such anomalous fluctuations could be caused by an extended giant branch,
consisting of either intermediate-age AGB stars above the tip of the
first-ascent giant branch or high-metallicity first-ascent giants, or by lack
of a full understanding of the K-band SBF calibration. This result raises
questions about the accuracy of K-band SBF distance measurements for elliptical
galaxies with unknown stellar composition and underscores the need for M_K
measurements over a larger range of color and luminosity.

</DOC>
<DOC>
<DOCNO> 8769 </DOCNO>
Nonequilibrium phase transition in a model for social influence


  We present extensive numerical simulations of the Axelrod's model for social
influence, aimed at understanding the formation of cultural domains. This is a
nonequilibrium model with short range interactions and a remarkably rich
dynamical behavior. We study the phase diagram of the model and uncover a
nonequilibrium phase transition separating an ordered (culturally polarized)
phase from a disordered (culturally fragmented) one. The nature of the phase
transition can be continuous or discontinuous depending on the model
parameters. At the transition, the size of cultural regions is power-law
distributed.

</DOC>
<DOC>
<DOCNO> 151003 </DOCNO>
A Construction of an Effective Hamiltonian from Feynman Diagrams:


  We study a similarity transformation to construct an effective Hamiltonian
systematically, which does not contain particle-number-changing interactions,
by means of Fukuda-Sawada-Taketani-Okubo's method. We show that such
Hamiltonian can be constructed from Feynman diagrams and give rules for
constructing it in the Light-Front Yukawa model. We prove that it is
renormalized by the familiar covariant perturbative renormalization procedure.
It is very advantageous that the effective Hamiltonian can be obtained from our
rules {\em immediately}. We also numerically diagonalize it to the second order
in the coupling constant as an exercise.

</DOC>
<DOC>
<DOCNO> 121877 </DOCNO>
Dynamics of Fe-Ni Bubbles in Young Supernova Remnants


  Observations of core-collapse supernovae (SNe) have revealed the presence of
extensive mixing of radioactive material in SN ejecta. The mixing of
radioactive material, mostly freshly synthesized Ni, is not complete, which
leads to a two-phase SN ejecta structure. The low-density phase consists of Fe
bubbles, created by the energy input from radioactive Co and Ni, surrounded by
compressed high-density metal-rich ejecta. We report on the theoretical
investigation of supernova remnant (SNR) dynamics with the two-phase SN ejecta.
We first present 3-dimensional hydrodynamic simulations of a single Fe bubble
immersed in an outer ejecta envelope, and compare the results with previous
work on shock-cloud interactions. We then consider randomly distributed Fe
bubbles with an average volume filling fraction of 1/2. We find that the
presence of Fe bubbles leads to vigorous turbulence and mixing of Fe with other
heavy elements and with the ambient normal-abundance gas. The turbulent energy
can be an order of magnitude larger than in the case of smooth ejecta. A
significant fraction of the shocked ejecta is found in narrow filaments and
clumps moving with radial velocities larger than the velocity of the forward
shock. Observational consequences of the two-phase ejecta on SNR X-ray spectra
and images are briefly mentioned.

</DOC>
<DOC>
<DOCNO> 80956 </DOCNO>
Eigenvalues of the hermitian Wilson-Dirac operator and chiral properties


  Chiral properties of QCD formulated with the domain-wall fermion (DWQCD) are
studied using the anomalous quark mass m_{5q} and the spectrum of the
4-dimensional Wilson-Dirac operator. Numerical simulations are made with the
standard plaquette gauge action and a renormalization-group improved gauge
action. Results are reported on the density of zero eigenvalue obtained with
the accumulation method, and a comparison is made with the results for m_{5q}.

</DOC>
<DOC>
<DOCNO> 40616 </DOCNO>
GENIUS-TF: a test facility for the GENIUS project


  GENIUS is a proposal for a large scale detector of rare events. As a first
step of the experiment, a small test version, the GENIUS test facility, will be
build up at the Laboratorio Nazionale del Gran Sasso (LNGS). With about 40 kg
of natural Ge detectors operated in liquid nitrogen, GENIUS-TF could exclude
(or directly confirm) the DAMA annual modulation signature within about two
years of measurement.

</DOC>
<DOC>
<DOCNO> 40226 </DOCNO>
Neutrino-Deuteron Scattering in Effective Field Theory at


  We study the four channels associated with neutrino-deuteron breakup
reactions at next-to-next to leading order in effective field theory. We find
that the total cross-section is indeed converging for neutrino energies up to
20 MeV, and thus our calculations can provide constraints on theoretical
uncertainties for the Sudbury Neutrino Observatory. We stress the importance of
a direct experimental measurement to high precision in at least one channel, in
order to fix an axial two-body counterterm.

</DOC>
<DOC>
<DOCNO> 8200 </DOCNO>
A first-order transition with power-law singularity in models with


  We study one- and two-dimensional models which undergo a transition between
active and absorbing phases. The transition point in these models is of novel
type: jump of the order parameter coincides with its power-law singularity.
Some arguments supported by Monte Carlo simulations prompted us to predict the
exact location of the transition point. Both models possess gauge-like
symmetry.

</DOC>
<DOC>
<DOCNO> 120567 </DOCNO>
A gravitational lens survey with Planck Surveyor


  The Planck Surveyor cosmic microwave background (CMB) imaging mission will
make very sensitive maps of the whole sky at microwave, millimetre (mm) and
sub-mm wavelengths. The steep source counts expected in the highest frequency
Planck bands are likely to be associated with a strong magnification bias, and
so the fraction of galaxies magnified by a factor of two or more could be
greater than 10%. In this paper, previous predictions of the significance of
the Planck survey for studies of lensing statistics are updated, to reflect our
expanded knowledge of the properties of high-redshift dusty galaxies, obtained
from far-infrared and sub-mm surveys. A catalogue of probably about 10000
galaxies, but perhaps as many as 100000 or as few as 1000, is expected to be
generated from the final Planck all-sky maps. Of order 1000 galaxies, a better
determined number, might reasonably be expected to be strongly lensed.
Co-ordinated sub-mm and far-infrared follow-up observations made using the
SPIRE and PACS instruments aboard the ESA cornerstone mission FIRST - Planck's
travelling companion to its L2 orbit - and the ground-based ALMA interferometer
array will provide accurate positions and very valuable information about the
spectral energy distributions (SEDs), redshifts and astrophysical properties of
the galaxies in the Planck catalogue. ALMA and radio images will also reveal
their morphology, and the characteristic arc and multiple image structures
produced by gravitational lensing. Studies of these bright sub-mm-selected
galaxies will allow new insight into the process of galaxy formation and
evolution.

</DOC>
<DOC>
<DOCNO> 69517 </DOCNO>
QCD factorization for exclusive, non-leptonic B meson decays: General


  We provide a rigorous basis for factorization for a large class of
non-leptonic two-body $B$-meson decays in the heavy-quark limit. The
factorization formula incorporates elements of the naive factorization approach
and the hard-scattering approach, but allows us to compute systematically
radiative (``non-factorizable'') corrections to naive factorization for decays
such as $B\to D\pi$ and $B\to \pi \pi$. We discuss the factorization formula
for a general final state from a general point of view. We then consider
factorization for decays into heavy-light final states (such as $B\to D\pi$) in
more detail, including a proof of the factorization formula at two-loop order.
Explicit results for the leading QCD corrections to factorization are presented
and compared to existing measurements of branching fractions and final-state
interaction phases.

</DOC>
<DOC>
<DOCNO> 67657 </DOCNO>
Probe of the Wtb coupling in $t \bar t$ pair production at Linear


  The Wtb vertex can be probed on future colliders in the processes of single
top production (LHC, pp mode, NLC, $\gamma e$ mode) and of top pair production
(NLC, e^+ e^- mode). We analyse observables sensitive to anomalous Wtb
couplings in the top pair production process of e^+ e^- collisions. In
particular, forward-backward and spin-spin asymmetries of the top decay
products and the asymmetry of the lepton energy spectum are considered.
Possible bounds on anomalous couplings obtained are competitive to those
expected from the upgraded Tevatron and LHC. The validity of the infinitely
small width approximation for the three-body top decay is also studied in
detail.

</DOC>
<DOC>
<DOCNO> 116587 </DOCNO>
Localized Beampipe Heating due to $e^-$ Capture and Nuclear Excitation


  At heavy ion colliders, two major sources of beam loss are expected to be
$e^+e^-$ production, where the $e^-$ is bound to one of the nuclei, and
photonuclear excitation and decay via neutron emission. Both processes alter
the ions charged to mass ratio by well defined amounts, creating beams of
particles with altered magnetic rigidity. These beams will deposit their energy
in a localized region of the accelerator, causing localized heating, The size
of the target region depends on the collider optics. For medium and heavy ions,
at design luminosity at the Large Hadron Collider, local heating may be more
than an order of magnitude higher than expected. This could cause magnet
quenches if the local cooling is inadequate. The altered-rigidity beams will
also produce localized radiation damage. The beams could also be extracted and
used for fixed target experiments.

</DOC>
<DOC>
<DOCNO> 8655 </DOCNO>
Dyon-Oscillator Duality


  The dyon-oscillator duality presented in this lecture can be treated as a
prototype of the Seiberg-Witten duality in nonrelativistic quantum mechanics.
The key statement declares that in some spatial dimensions the oscillator-like
systems are dual to the atoms composed of the electrical charged particle and
dyon, i.e., monopoles provided by both magnetic and electric charge.

</DOC>
<DOC>
<DOCNO> 9061 </DOCNO>
Stochastic Aggregation: Scaling Properties


  We study scaling properties of stochastic aggregation processes in one
dimension. Numerical simulations for both diffusive and ballistic transport
show that the mass distribution is characterized by two independent nontrivial
exponents corresponding to the survival probability of particles and monomers.
The overall behavior agrees qualitatively with the mean-field theory. This
theory also provides a useful approximation for the decay exponents, as well as
the limiting mass distribution.

</DOC>
<DOC>
<DOCNO> 8268 </DOCNO>
Stochastic Models of Exotic Transport


  Non-typical transport phenomena may arise when randomly driven particles
remain in an active relationship with the environment instead of being passive.
If we attribute to Brownian particles an ability to induce alterations of the
environment on suitable space-time scales, those in turn must influence their
further movement. In that case a general feedback mechanism needs to be
respected. By resorting to a specific choice of the particle-bath coupling, an
enhanced (super-diffusion) or non-dispersive diffusion-typ processes are found
to exist in generically non-equilibrium contexts.

</DOC>
<DOC>
<DOCNO> 13049 </DOCNO>
Imprints of Nonextensivity in Multiparticle Production


  The statistical methods based on the classical Boltzmann-Gibbs (BG) approach
are at heart of essentially all descriptions of multiparticle production
processes. In many cases, however, one observes some deviations from the
expected behaviour. It is also known that conditions necessary for the BG
statistics to apply are usually satisfied only approximately. Two attitudes are
possible in such situations: either to abandon statistical approach trying some
other model or to generalise it to the so called nonextensive statistics
(widely used in the similar circumstances in many other branches of physics).
We shall provide here an overview of possible imprints of non-extensitivity
existing both in high energy cosmic ray physics and in multiparticle production
processes in hadronic collisions, in particular in heavy ion collisions.

</DOC>
<DOC>
<DOCNO> 100768 </DOCNO>
Optimally defined Racah-Casimir operators for su(n) and their


  This paper deals with the striking fact that there is an essentially
canonical path from the $i$-th Lie algebra cohomology cocycle, $i=1,2,... l$,
of a simple compact Lie algebra $\g$ of rank $l$ to the definition of its
primitive Casimir operators $C^{(i)}$ of order $m_i$. Thus one obtains a
complete set of Racah-Casimir operators $C^{(i)}$ for each $\g$ and nothing
else. The paper then goes on to develop a general formula for the eigenvalue
$c^{(i)}$ of each $C^{(i)}$ valid for any representation of $\g$, and thereby
to relate $c^{(i)}$ to a suitably defined generalised Dynkin index. The form of
the formula for $c^{(i)}$ for $su(n)$ is known sufficiently explicitly to make
clear some interesting and important features. For the purposes of
illustration, detailed results are displayed for some classes of representation
of $su(n)$, including all the fundamental ones and the adjoint representation.

</DOC>
<DOC>
<DOCNO> 118433 </DOCNO>
On the origin of the universe


  It has been proven recently that the Standard Model of particle physics has
electric charge quantization built into it. It has also been shown by the
author that there was no electric charge in the early universe. Further it is
shown here that the restoration of the full Standard Model symmetry (as in the
Early Universe) leads to the result that `time', `light', along with it's
velocity c and the theory of relativity, all lose any physical meaning. The
physical Universe as we know it, with its space-time structure, disappears in
this phase transition. Hence it is hypothesized here that the Universe came
into existence when the Standard Model symmetry $SU(3)_C \otimes SU(2)_L
\otimes U(1)_Y$ was spontaneously broken to $SU(3)_C \otimes U(1)_{em}$. This
does not require any spurious extensions of the Standard Model and in a simple
and consistent manner explains the origin of the Universe within the framework
of the Standard Model itself.

</DOC>
<DOC>
<DOCNO> 178563 </DOCNO>
Properties of $^{12}$C in the {\it ab initio} nuclear shell-model


  We obtain properties of $^{12}$C in the {\it ab initio} no-core nuclear
shell-model. The effective Hamiltonians are derived microscopically from the
realistic CD-Bonn and the Argonne V8' nucleon-nucleon (NN) potentials as a
function of the finite harmonic oscillator basis space. Binding energies,
excitation spectra and electromagnetic properties are presented for model
spaces up to $5\hbar\Omega$. The favorable comparison with available data is a
consequence of the underlying NN interaction rather than a phenomenological
fit.

</DOC>
<DOC>
<DOCNO> 72129 </DOCNO>
Can we distinguish an MSSM Higgs from a SM Higgs at a Linear Collider?


  We study the prospects for distinguishing the CP-even Higgs boson of the
minimal supersymmetric extension of the Standard Model (MSSM) from the Standard
Model (SM) Higgs boson by measuring its branching ratios at an e+e- linear
collider. The regions of the M_A - tan beta plane in which an MSSM Higgs boson
can be distinguished from the SM Higgs boson depend strongly upon the
supersymmetric parameters that enter the radiative corrections to the Higgs
mass matrix and the Higgs couplings to fermions. In some regions of parameter
space it is possible to extract the supersymmetric correction to the relation
between the b quark mass and its Yukawa coupling from Higgs branching ratio
measurements.

</DOC>
<DOC>
<DOCNO> 120384 </DOCNO>
Oxygen Abundance Determination in Very Metal-Deficient Giants: Permitted


  The abundance of oxygen was determined for selected very metal-poor G-K stars
(six giants and one turn-off star) based on the high S/N and high-resolution
spectra observed with Keck HIRES in the red through near-IR region comprising
the permitted O I lines (7771-5, 8446) along with the [O I] forbidden line at
6363 A. It turned out that both the abundances from the permitted line
features, O I 7771-5 and O I 8446, agree quite well with each other, while the
forbidden line yields somewhat discrepant and divergent abundances with a
tendency of being underestimated on the average. The former (7773/8446)
solution, which we believe to be more reliable, gives a fairly tight [O/Fe] vs.
[Fe/H] relation such that increasing steadily from [O/Fe] = 0.6 (at [Fe/H] =
-1.5) to [O/Fe] = 1.0 (at [Fe/H] = -3.0), in reasonable consistency with the
trend recently reported based on the analysis of the UV OH lines. We would
suspect that some kind of weakening mechanism may occasionally act on the
formation of [O I] forbidden lines in metal-poor stars. Therefore, [O I] lines
may not be so a reliable abundance indicator as has been generally believed.

</DOC>
<DOC>
<DOCNO> 119396 </DOCNO>
Mapping IR Enhancements in Closely Interacting Spiral-Spiral Pairs. I.


  Mid-infrared (MIR) imaging and spectroscopic observations are presented for a
well defined sample of eight closely interacting (CLO) pairs of spiral galaxies
that have overlapping disks and show enhanced far-infrared (FIR) emission. The
goal is to study the star formation distribution in CLO pairs, with special
emphasis on the role of 'overlap starbursts'. Observations were made with the
Infrared Space Observatory (ISO) using the CAM and SWS instruments. The ISO~CAM
maps, tracing the MIR emission of warm dust heated by young massive stars, are
compared to new ground based H$\alpha$ and R-band images. We identify three
possible subgroups in the sample, classified according to the star formation
morphology: (1) advanced mergers (Arp~157, Arp~244 and Arp~299), (2) severely
disturbed systems (Arp~81 and Arp~278), and (3) less disturbed systems
(Arp~276, KPG 347 and KPG 426). Localized starbursts are detected in the
overlap regions in all five pairs of subgroups (1) and (2), suggesting that
they are a common property in colliding systems. Except for Arp~244, the
'overlap starburst' is usually fainter than the major nuclear starburst in CLO
pairs. Star formation in 'less disturbed systems' is often distributed
throughout the disks of both galaxies with no 'overlap starburst' detected in
any of them. These systems also show less enhanced FIR emission, suggesting
that they are in an earlier interaction stage than pairs of the other two
subgroups where the direct disk collisions have probably not yet occurred.

</DOC>
<DOC>
<DOCNO> 12129 </DOCNO>
Monoclinic and triclinic phases in higher-order Devonshire theory


  Devonshire theory provides a successful phenomenological description of many
cubic perovskite ferroelectrics such as BaTiO3 via a sixth-order expansion of
the free energy in the polar order parameter. However, the recent discovery of
a novel monoclinic ferroelectric phase in the PZT system by Noheda et al.
(Appl. Phys. Lett. 74, 2059 (1999)) poses a challenge to this theory. Here, we
confirm that the sixth-order Devonshire theory cannot support a monoclinic
phase, and consider extensions of the theory to higher orders. We show that an
eighth-order theory allows for three kinds of equilibrium phases in which the
polarization is confined not to a symmetry axis but to a symmetry plane. One of
these phases provides a natural description of the newly observed monoclinic
phase. Moreover, the theory makes testable predictions about the nature of the
phase boundaries between monoclinic, tetragonal, and rhombohedral phases. A
ferroelectric phase of the lowest (triclinic) symmetry type, in which the
polarization is not constrained by symmetry, does not emerge until the
Devonshire theory is carried to twelfth order. A topological analysis of the
critical points of the free-energy surface facilitates the discussion of the
phase transition sequences.

</DOC>
<DOC>
<DOCNO> 152228 </DOCNO>
Noncommutative instantons revisited


  We find a new gauge in which U(1) noncommutative instantons are explicitly
non-singular on the whole noncommutative R^4, thus resolving the previous
confusions of the author. We start with the pedagogical introduction to the
noncommutative gauge theories.

</DOC>
<DOC>
<DOCNO> 11500 </DOCNO>
Signatures of Spin and Charge Energy Scales in the Local Moment and


  Local moment formation driven by the on--site repulsion $U$ is one of the
most fundamental features in the Hubbard model. At the simplest level, the
temperature dependence of the local moment is expected to have a single
structure at $T \sim U$, reflecting the suppression of the double occupancy. In
this paper we show new low temperature Quantum Monte Carlo data which emphasize
that the local moment also has a signature at a lower energy scale which
previously had been thought to characterize only the temperatures below which
moments on {\it different} sites begin to correlate locally. We discuss
implications of these results for the structure of the specific heat, and
connections to quasiparticle resonance and pseudogap formation in the density
of states.

</DOC>
<DOC>
<DOCNO> 9737 </DOCNO>
First order phase transition in a nonequilibrium growth process


  We introduce a simple continuous model for nonequilibrium surface growth. The
dynamics of the system is defined by the KPZ equation with a Morse-like
potential representing a short range interaction between the surface and the
substrate. The mean field solution displays a non trivial phase diagram with a
first order transition between a growing and a bound surface, associated with a
region of coexisting phases, and a tricritical point where the transition
becomes second order. Numerical simulations in 3 dimensions show quantitative
agreement with mean field results, and the features of the phase space are
preserved even in 2 dimensions.

</DOC>
<DOC>
<DOCNO> 69615 </DOCNO>
pi <---> K Meson Vacuum Transitions (Oscillations) in Diagram Approach


  The elements of the theory of vacuum oscillations and the model of dynamical
expansion of the theory of weak interactions works at the tree level, i.e. the
model of dynamical analogy of Cabibbo-Kobayashi- Maskawa matrices and its
further development, are given. It is shown that the quarks and massive vector
bosons must be structural and these structural particles (subparticles) must
interact to generate quark and vector boson masses. In this case the problem of
singularity cancellations does not arise in this model. It is also shown that,
for self consistency of the theory, the weak decays of $K$ mesons must go
through massive vector boson $B$ but not $W$ boson. In the framework of this
model the probability of $\pi \leftrightarrow K$ transitions (oscillations) in
the diagram approach is computed. These transitions are virtual since masses of
$\pi$ and $K$ mesons differ considerably. These transitions (oscillations) can
be registered through $K$ decays after transitions of virtual $K$ mesons to
their own mass shell by using their quasielastic strong interactions.

</DOC>
<DOC>
<DOCNO> 40034 </DOCNO>
Study of Charmless Hadronic B Meson Decays to Pseudoscalar-Vector Final


  We report results of searches for charmless hadronic B meson decays to
pseudoscalar(pi^+-,K^+-,Pi^0 or Ks^0)-vector(Rho, K* or Omega) final states.
Using 9.7 million BBbar pairs collected with the CLEO detector, we report first
observation of B^- --> Pi^-Rho^0, B^0 --> Pi^+-Rho^-+ and B^- --> Pi^-Omega,
which are expected to be dominated by hadronic b --> u transitions. The
measured branching fractions are (10.4+3.3-3.4+-2.1)x10^-6,
(27.6+8.4-7.4+-4.2)x10^-6 and (11.3+3.3-2.9+-1.4)x10^-6, respectively.
Branching fraction upper limits are set for all the other decay modes
investigated.

</DOC>
<DOC>
<DOCNO> 169967 </DOCNO>
Entanglement, thermalisation and stationarity: The computational


  'Tis said, to know others is to be learned, to know oneself, wise - I
demonstrate that it could be more fundamental than knowing the rest of nature,
by applying classical computational principles and engineering hindsight to
derive and explain quantum entanglement, state space formalism and the
statistical nature of quantum mechanics. I show that an entangled photon pair
is literally no more than a 1-bit hologram, that the quantum state formalism is
completely derivable from general considerations of representation of physical
information, and that both the probabilistic aspects of quantum theory and the
constancy of h are exactly predicted by the thermodynamics of representation,
without precluding a fundamental, relative difference in spatial scale between
non-colocated observers, leading to logical foundations of relativity and
cosmology that show the current thinking in that field to be simplistic and
erroneous.

</DOC>
<DOC>
<DOCNO> 83247 </DOCNO>
Semantic Parsing based on Verbal Subcategorization


  The aim of this work is to explore new methodologies on Semantic Parsing for
unrestricted texts. Our approach follows the current trends in Information
Extraction (IE) and is based on the application of a verbal subcategorization
lexicon (LEXPIR) by means of complex pattern recognition techniques. LEXPIR is
framed on the theoretical model of the verbal subcategorization developed in
the Pirapides project.

</DOC>
<DOC>
<DOCNO> 101515 </DOCNO>
Braid structures in knot complements, handlebodies and 3-manifolds


  We consider braids on $m+n$ strands, such that the first $m$ strands are
trivially fixed.
 We denote the set of all such braids by $B_{m,n}$. Via concatenation $B_{m,n}$
acquires a group structure. The objective of this paper is to find a
presentation for $B_{m,n}$ using the structure of its corresponding pure braid
subgroup, $P_{m,n}$, and the fact that it is a subgroup of the classical Artin
group $B_{m+n}$. Then we give an irredundant presentation for $B_{m,n}$. The
paper concludes by showing that these braid groups or appropriate cosets of
them are related to knots in handlebodies, in knot complements and in c.c.o.
3--manifolds.

</DOC>
<DOC>
<DOCNO> 100151 </DOCNO>
Affine embeddings of homogeneous spaces


  Let G be a reductive algebraic group and let H be a reductive subgroup of G.
We describe all pairs (G,H) such that for any affine G-variety X with a dense
G-orbit isomorphic to G/H the number of G-orbits in X is finite. The maximal
number of parameters in families of G-orbits in all affine embeddings of G/H is
computed.

</DOC>
<DOC>
<DOCNO> 119367 </DOCNO>
Hipparcos, IUE, and the Stellar Content of the Solar Neighbourhood


  The spectroscopic parallaxes in the Hipparcos catalogue can be used to
translate absolute stellar fluxes observed at Earth to the fluxes emerging at
the stellar surface for nearby stars. The comparison of these fluxes with the
predictions of theoretical model atmospheres allows us to determine the
effective temperature and the metallicity of the stars. It is suggested that is
possible to study the stellar content of the solar neighbourhood making use of
the large number of ultraviolet spectra in the archive of the IUE satellite.

</DOC>
<DOC>
<DOCNO> 71605 </DOCNO>
Analytic model of Regge trajectories


  A model for a Regge trajectory compatible with the threshold behavior
required by unitarity and asymptotics in agreement with analyticity constraints
is given in explicit form. The model is confronted in the time-like region with
widths and masses of the mesonic resonances and, in the space-like region, the
$\rho$ trajectory is compared with predictions derived from $\pi-N$
charge-exchange reaction. Breaking of the exchange degeneracy is studied in the
model and its effect on both the masses and widths is determined.

</DOC>
<DOC>
<DOCNO> 84807 </DOCNO>
Null cone evolution of axisymmetric vacuum spacetimes


  We present the details of an algorithm for the global evolution of
asymptotically flat, axisymmetric spacetimes, based upon a characteristic
initial value formulation using null cones as evolution hypersurfaces. We
identify a new static solution of the vacuum field equations which provides an
important test bed for characteristic evolution codes. We also show how
linearized solutions of the Bondi equations can be generated by solutions of
the scalar wave equation, thus providing a complete set of test beds in the
weak field regime. These tools are used to establish that the algorithm is
second order accurate and stable, subject to a Courant-Friedrichs-Lewy
condition. In addition, the numerical versions of the Bondi mass and news
function, calculated at scri on a compactified grid, are shown to satisfy the
Bondi mass loss equation to second order accuracy. This verifies that numerical
evolution preserves the Bianchi identities. Results of numerical evolution
confirm the theorem of Christodoulou and Klainerman that in vacuum, weak
initial data evolve to a flat spacetime. For the class of asymptotically flat,
axisymmetric vacuum spacetimes, for which no nonsingular analytic solutions are
known, the algorithm provides highly accurate solutions throughout the regime
in which neither caustics nor horizons form.

</DOC>
<DOC>
<DOCNO> 116531 </DOCNO>
Imprints of Discrete Space Time - A Brief Note


  We point out that the observed decay mode of the pion and the Kaon decay
puzzle are really imprints of discrete micro space-time.

</DOC>
<DOC>
<DOCNO> 84843 </DOCNO>
Some Comments of Vlasov-Liouville Equation and its Relation with


  We discuss here the possibility to write the Liouville-Vlasov equation for
the Wigner-function of a spinor field coupled to a gauge field with field
strength tensor $F^{\mu\nu}$ in a curved space-time versus a local Lorentz
manifold (introduction of local Lorentz coordinates) with an appropriate
definition of a covariant derivative carried out using a spin connection
$B_{\mu}^{ab}(x)$.

</DOC>
<DOC>
<DOCNO> 68425 </DOCNO>
Mirror matter and heavy singlet neutrino oscillations in the early


  We investigate the mixing of heavy gauge singlet neutrinos in a mirror matter
model employing the seesaw mechanism. The parameter constraints that must be
satisfied to prevent the overproduction of mirror matter in the early universe
are deduced. We find that no fine tuning in the heavy neutral fermion sector is
required for this mirror matter model to satisfy cosmological constraints.
Baryogenesis scenarios are briefly discussed in the context of the mirror
model.

</DOC>
<DOC>
<DOCNO> 68144 </DOCNO>
Constraints on Two-Higgs Doublet Models at Large tan{beta} from W and Z


  We study constraints on type-II two Higgs doublet models at large tan{beta}
from LEP/SLD Z-pole data and from lepton universality violation in W decay. We
perform a global fit and find that, in the context of Z decay, the LEP/SLD
experimental values for lepton universality violation, R_b, and A_b all
somewhat disfavor the model. Contributions from the neutral Higgs sector can be
used to constrain the scalar-pseudoscalar Higgs mass splittings. Contributions
from the charged Higgs sector allow us to constrain the charged Higgs mass. For
tan{beta}=100 we obtain the 1 sigma classical (Bayesian) bounds of m_{H+} > 670
GeV (370 GeV) and 1 > m_{h0}/m_{A0} > 0.68 (0.64). The 2 sigma bounds are weak.
Currently, the Tevatron experimental limits on lepton universality violation in
W decay provide no significant constraint on the Higgs sector.

</DOC>
<DOC>
<DOCNO> 67742 </DOCNO>
Long distance contribution to $B^- \to K^- K^- \pi^+$, - a searching


  The decay $B^- \to K^- K^- \pi^+$ has been sugested as a test for minimal
supersymmetric standard model and for supersymmetric models with R-parity
violating couplings, in view of its extreme smallnesss in the standard model.
We calculate two long distance contributions to this decay, that associated
with $DD$ and $D\pi$ intermediate states and that induced by virtual $D$, $\pi$
mesons. The branching ratio due to these contributions is $6 \times 10^{-12}$,
which is somewhat smaller than the standard model short distance result,
leaving this decay free for the search of new physics.

</DOC>
<DOC>
<DOCNO> 13867 </DOCNO>
Comment on ''Low to High Spin-state Transition Induced by charge


  In the commented Letter Vogt et al. (Phys.Rev.Lett. 84 (2000) 2969) claim the
existence of a spin-state transition in YBaCo2O5. We think that this claim
about the change from the low spin to high spin state upon cooling in YBaCo2O5
is errorneous. Keywords: magnetism, 3d ions, low spin.

</DOC>
<DOC>
<DOCNO> 122910 </DOCNO>
Destruction of protoplanetary disks in the Orion Nebula Cluster


  We use numerical N-body simulations of the Orion Nebula Cluster (ONC) to
investigate the destruction of protoplanetary disks by close stellar encounters
and UV radiation from massive stars. The simulations model a cluster of 4000
stars, and we consider separately cases in which the disks have fixed radii of
100 AU and 10 AU. In the former case, depending on a star's position and orbit
in the cluster over 10^7 years, UV photoevaporation removes at least 0.01 Msol
from its disk, and can remove up to 1 Msol. We find no dynamical models of the
ONC consistent with the suggestion of Storzer and Hollenbach that the observed
distribution and abundance of proplyds could be explained by a population of
stars on radial orbits which spend relatively little time near Theta 1C Ori
(the most massive star in the ONC). Instead the observations require either
massive disks (e.g. a typical initial disk mass of 0.4 Msol) or a very recent
birth for Theta 1C Ori. When we consider the photoevaporation of the inner 10
AU of disks in the ONC, we find that planet formation would be hardly affected.
Outside that region, planets would be prevented from forming in about half the
systems, unless either the initial disk masses were very high or they formed in
less than ~ 2 Myr and Theta 1C Ori has only very recently appeared. We also
present statistics on the distribution of minimum stellar encounter
separations. This peaks at 1000 AU, with less than 10% of stars having had an
encounter closer than 100 AU after 10^7 years. We conclude that stellar
encounters are unlikely to play a significant role in destroying protoplanetary
disks. In the absence of any disruption mechanism other than those considered
here, we would thus predict planetary systems like our own to be common amongst
stars forming in ONC-like environments.

</DOC>
<DOC>
<DOCNO> 170390 </DOCNO>
General procedure of solving the time-dependent Schr\"odinger equation


  A nonperturbative procedure of solving the time-dependent Schr\"odinger
equation, called the multi-projection approach or phase dynamics of quantum
mechanics, is derived and illustrated. In addition to introducing a method with
that time-dependent systems become solvable (under the assumption that
corresponding time-independent systems are solvable), the new approach unveils
several misconcepts related to the usual wavefunction expansion and the
standard perturbation theory.

</DOC>
<DOC>
<DOCNO> 13159 </DOCNO>
Circulation-Strain Sum Rule in Stochastic Magnetohydrodynamics


  We study probability density functions (pdfs) of the circulation of velocity
and magnetic fields in magnetohydrodynamics, computed for a circular contour
within inertial range scales. The analysis is based on the instanton method as
adapted to the Martin-Siggia-Rose field theory formalism. While in the viscous
limit the expected gaussian behaviour of fluctuations is indeed verified, the
case of vanishing viscosity is not suitable of a direct saddle-point treatment.
To study the latter limit, we take into account fluctuations around
quasi-static background fields, which allows us to derive a sum rule relating
pdfs of the circulation observables and the rate of the strain tensor. A simple
inspection of the sum rule definition leads straightforwardly to the algebraic
decay $\rho(\Gamma) \sim 1/ \Gamma^2$ at the circulation pdf tails.

</DOC>
<DOC>
<DOCNO> 121067 </DOCNO>
Cosmological Microlensing


  Variability in gravitationally lensed quasars can be due to intrinsic
fluctuations of the quasar or due to ``microlensing'' by compact objects along
the line of sight. If disentangled from each other, microlens-induced
variability can be used to study two cosmological issues of great interest, the
size and brightness profile of quasars on one hand, and the distribution of
compact (dark) matter along the line of sight on the other. In particular,
multi-waveband observations are useful for this goal.
  In this review recent theoretical progress as well as observational evidence
for quasar microlensing over the last few years will be summarized. Comparison
with numerical simulations will show where we stand. Particular emphasis will
be given to the questions microlensing can address regarding the search for
dark matter, both in the halos of lensing galaxies and in a cosmologically
distributed form. A discussion of desired observations and required theoretical
studies will be given as a conclusion/outlook.

</DOC>
<DOC>
<DOCNO> 170728 </DOCNO>
Diagonalization of Hamiltonians, uncertainty matrices and Robertson


  The problem of diagonalization of Hamiltonians of N-dimensional boson systems
by means of time-dependent canonical transformations (CT) is considered, the
case of quadratic Hamiltonians being treated in greater detail. The unitary
generator of time-dependent CT which can transform any Hamiltonian to that of a
system of uncoupled stationary oscillators is constructed. The close
relationship between methods of canonical transformations, time-dependent
integrals of motion and dynamical symmetry is noted.
  The diagonalization and symplectic properties of the uncertainty matrix for
2N canonical observables are studied. It is shown that the normalized
uncertainty matrix is symplectic for the squeezed multimode Glauber coherent
states and for the squeezed Fock states with equal photon numbers in each mode.
The Robertson uncertainty relation for the dispersion matrix of canonical
observables is shown to be minimized in squeezed coherent states only.

</DOC>
<DOC>
<DOCNO> 70200 </DOCNO>
Collider signals of brane fluctuations


  Assuming that we live on a non rigid brane with TeV-scale tension, the scalar
fields that control the coordinates of our brane in the extra dimensions give
rise to missing energy signals at high-energy colliders with a characteristic
angular and energy spectrum, identical to the one due to graviton emission in 6
extra dimensions. LEP bounds and LHC capabilities are analyzed.

</DOC>
<DOC>
<DOCNO> 102827 </DOCNO>
Transitive permutation groups of prime-squared degree


  We explicitly determine all of the transitive groups of degree p-squared, p a
prime, whose Sylow p-subgroup is not the wreath product of two cyclic groups of
order p. Furthermore, we provide a general description of the transitive groups
of degree p-squared whose Sylow p-subgroup is such a wreath product, and
explicitly determine most of them. As applications, we solve the Cayley
Isomorphism problem for Cayley objects of an abelian group of order p-squared,
explicitly determine the full automorphism group of Cayley graphs of abelian
groups of order p-squared, and find all nonnormal Cayley graphs of order
p-squared.

</DOC>
<DOC>
<DOCNO> 120864 </DOCNO>
The Structure and Emission of the Accretion Shock in T Tauri Stars II:


  We compare accretion shock models with optical and ultraviolet spectra of
pre-main sequence stars to (1) make the first determinations of accretion rates
in intermediate mass T Tauri stars from continuum emission, and (2) derive
improved estimates of accretion rates and extinctions for continuum T Tauri
stars. Our method extends the shock models developed by Calvet and Gullbring to
enable comparisons with optical and archival International Ultraviolet Explorer
ultraviolet spectra. We find good agreement between the observations and the
model predictions, supporting the basic model of magnetospheric accretion
shocks as well as previous determinations of accretion rates and interstellar
reddening for the low mass T Tauri stars. The accretion rates determined for
the intermediate-mass T Tauri stars agree well with values obtained through
other methods that use near-infrared hydrogen line strengths (Muzerolle et al.
1998).

</DOC>
<DOC>
<DOCNO> 116563 </DOCNO>
Is it Possible to Describe Economical Phenomena by Methods of


  The methods of statistical physics of open systems are used for describing
the time dependence of economic characteristics (income, profit, cost, supply,
currency etc.) and their correlations with each other. Nonlinear equations
(analogies of known reaction-diffusion, kinetic, Langevin equation) describing
appearance of bifurcations, self-sustained oscillational processes,
self-organizations in economic phenomena are offered.

</DOC>
<DOC>
<DOCNO> 80728 </DOCNO>
Vortices in SU(2) lattice gauge theory


  We investigate some properties of thick vortices and thick monopoles in the
SU(2) lattice gauge theory by inserting operators which create these
excitations. Some quantities associated with the dynamical behaviour of thick
vortices and thick monopoles are studied. We measure the derivative of the free
energy of the vortex with respect to the coupling and we find that it falls
exponentially with the cross sectional area of the vortex size. We also study
the monopole-monopole potential energy for thick and thin monopoles. Our
results suggest that vortices and monopoles of increasing thickness will play
an important role in the large $\beta$ limit.

</DOC>
<DOC>
<DOCNO> 7895 </DOCNO>
Lattice model for kinetics and grain size distribution in


  We propose a simple, versatile and fast computational model tounderstand the
deviations from the well-known Kolmogorov-Johnson-Mehl-Avrami kinetic
theoryfound in metal recrystallization and amorphous semiconductor
crystallization. Our model describes in detail the kinetics of the
transformation and the grain size distribution of the product material, and is
in good agreement with the available experimental data. Other morphological and
kinetic features amenable of experimental observation are outlined, suggesting
new directions for further validation of the model.

</DOC>
<DOC>
<DOCNO> 170018 </DOCNO>
Low temperature dynamics and laser-cooling of two-species Coulomb chains


  We study from the point of view of quantum logic the properties of the
collective oscillations of a linear chain of ions trapped in a linear Paul trap
and composed of two ion species. We discuss extensively sympathetic cooling of
the chain and the effect of anharmonicity on laser-cooling and
quantum-information processing.

</DOC>
<DOC>
<DOCNO> 67924 </DOCNO>
Further investigation of a relic neutralino as a possible origin of an


  We analyze the annual-modulation effect, measured by the DAMA Collaboration
with the new implementation of a further two-years running, in the context of a
possible interpretation in terms of relic neutralinos. We impose over the set
of supersymmetric configurations, selected by the annual-modulation data, the
constraints derived from WIMP indirect measurements, and discuss the features
of the ensuing relic neutralinos. We critically discuss the sources of the main
theoretical uncertainties in the analysis of event rates for direct and
indirect WIMP searches.

</DOC>
<DOC>
<DOCNO> 100072 </DOCNO>
The approximation numbers of Hardy--type operators on trees


  The Hardy operator $T_a$ on a tree $\G$ is defined by \[(T_af)(x):=v(x)
\int^x_a u(t)f(t) dt \qquad {for} a, x\in \G. \] Properties of $T_a$ as a map
from $L^p(\G)$ into itself are established for $1\le p \le \infty$. The main
result is that, with appropriate assumptions on $u$ and $v$, the approximation
numbers $a_n(T_a)$ of $T_a$ satisfy \[ (*) \lim_{n\to \infty} na_n(T_a) =
\alpha_p\int_{\G} |uv|dt \] for a specified constant $\alpha_p$ and
$1<p<\infty$. This extends results of Naimark, Newman and Solomyak for $p=2$.
Hitherto, for $p\neq 2$, (*) was unknown even when $\G$ is an interval. Also,
upper and lower estimates for the $l^q$ and weak-$l^q$ norms of $\{a_n(T_a)\}$
are determined.

</DOC>
<DOC>
<DOCNO> 8579 </DOCNO>
Quasiparticle Tunnelling and Field-Dependent Critical Current in


  Intrinsic c-axis tunnelling in the superconducting state has been measured in
zero and finite fields in small mesa structures fabricated on the surface of
2212-BSCCO single crystals. The temperature dependence of the zero-field
critical current and quasi-particle conductance is related to microscopic
d-wave models in the presence of impurity scattering. The strong field
dependence of the c-axis critical current provides information on the
correlation of flux pancakes across adjacent superconducting bi-layers. An
instability in the IV characteristics is observed below 20K, which accounts for
the apparent drop in critical current at low temperatures previously reported.

</DOC>
<DOC>
<DOCNO> 40265 </DOCNO>
$\bar d - \bar u$ asymmetry and semi-inclusive production of pions in


  We investigate unambiguities in the extraction of the $\bar d - \bar u$
asymmetry from semi-inclusive production of pions in DIS. The role of several
effects beyond the quark-parton model (QPM) which lead to $N_p^{\pi^+} \ne
N_n^{\pi^+}$ and $N_p^{\pi^-} \ne N_n^{\pi^-}$ and may therefore cloud such an
extraction is studied. The results are discussed in the context of the recent
HERMES data. We find that the interaction of the resolved photon with the
nucleon significantly modifies the observed $\bar d - \bar u$ asymmetry. The
exclusive elastic production of $\rho$ mesons plays a similar role for the
large-$z$ data sample. Our estimate shows a rather small effect of the
spectator mechanism. Nuclear effects in the deuteron also look potentially
important but are difficult to estimate quantitatively.
   Throughout the paper we make in addition several general remarks concerning
semi-inclusive and exclusive production of mesons.

</DOC>
<DOC>
<DOCNO> 84567 </DOCNO>
Signature Changing Space-times and the New Generalised Functions


  A signature changing spacetime is one where an initially Riemannian manifold
with Euclidean signature evolves into the Lorentzian universe we see today.
This concept is motivated by problems in causality implied by the isotropy and
homogeneity of the universe. As initially time and space are indistinguishable
in signature change, these problems are removed. There has been some dispute as
to the nature of the junction conditions across the signature change, and in
particular, whether or not the metric is continuous there. We determine to what
extent the Colombeau algebra of new generalised functions resolves this dispute
by analysing both types of signature change within its framework. A covariant
formulation of the Colombeau algebra is used, in which the usual properties of
the new generalised functions are extended. We find that the Colombeau algebra
is insufficient to preclude either continuous or discontinuous signature
change, and is also unable to settle the dispute over the nature of the
junction conditions.

</DOC>
<DOC>
<DOCNO> 119017 </DOCNO>
On the Efficiency of Internal Shocks in Gamma-Ray Bursts


  The fraction of a fireball kinetic kinetic energy that can be radiated away
by internal shocks is sensitive to the amplitude of initial fluctuations in the
fireball. We give a simple analytical description for dissipation of
modest-amplitude fluctuations and confirm it with direct numerical simulations.
At high amplitudes, the dissipation occurs in a non-linear regime with
efficiency approaching 100 %. Most of the explosion energy is then radiated
away by the prompt GRB and only a fraction remains to be radiated by the
afterglow.

</DOC>
<DOC>
<DOCNO> 71852 </DOCNO>
Isospin Symmetry Breaking and the $\rho-\omega$-System


  Simple quark models for the low lying vector mesons suggest a mixing between
the u- and d-flavors and a violation of the isospin symmetry for the
$\rho-\omega$- system much stronger than observed. It is shown that the chiral
dynamics, especially the QCD anomaly, is responsible for a restoration of the
isospin symmetry in the $\rho-\omega$-system.

</DOC>
<DOC>
<DOCNO> 169863 </DOCNO>
Unconventional Quantum Computing Devices


  This paper investigates a variety of unconventional quantum computation
devices, including fermionic quantum computers and computers that exploit
nonlinear quantum mechanics. It is shown that unconventional quantum computing
devices can in principle compute some quantities more rapidly than
`conventional' quantum computers.

</DOC>
<DOC>
<DOCNO> 100223 </DOCNO>
Existence and properties of p-tupling fixed points


  We prove the existence of fixed points of p-tupling renormalization operators
for interval and circle mappings having a critical point of arbitrary real
degree r > 1. Some properties of the resulting maps are studied: analyticity,
univalence, behavior as $r$ tends to infinity.

</DOC>
<DOC>
<DOCNO> 9881 </DOCNO>
Elastic scattering loss of atoms from colliding Bose-Einstein condensate


  Bragg diffraction of atoms by light waves has been used to create high
momentum components in a Bose-Einstein condensate. Collisions between atoms
from two distinct momentum wavepackets cause elastic scattering that can remove
a significant fraction of atoms from the wavepackets and cause the formation of
a spherical shell of scattered atoms. We develop a slowly varying envelope
technique that includes the effects of this loss on the condensate dynamics
described by the Gross-Pitaevski equation. Three-dimensional numerical
calculations are presented for two experimental situations: passage of a moving
daughter condensate through a non-moving parent condensate, and four-wave
mixing of matter waves.

</DOC>
<DOC>
<DOCNO> 8621 </DOCNO>
Macroscopic and Microscopic (Non-)Universality of Compact Support Random


  A random matrix model with a sigma-model like constraint, the restricted
trace ensemble (RTE), is solved in the large-n limit. In the macroscopic limit
the smooth connected two-point resolvent G(z,w) is found to be non-universal,
extending previous results from monomial to arbitrary polynomial potentials.
Using loop equation techniques we give a closed though non-universal expression
for G(z,w), which extends recursively to all higher k-point resolvents. These
findings are in contrast to the usual unconstrained one-matrix model. However,
in the microscopic large-n limit, which probes only correlations at distance of
the mean level spacing, we are able to show that the constraint does not modify
the universal sine-law. In the case of monomial potentials $V(M)=M^{2p}$, we
provide a relation valid for finite-n between the k-point correlation function
of the RTE and the unconstrained model. In the microscopic large-n limit they
coincide which proves the microscopic universality of RTEs.

</DOC>
<DOC>
<DOCNO> 40581 </DOCNO>
Physics results from BABAR and prospects


  The BABAR experiment has been taking data since about one year. Physics
results, complementary to those described by G.Sciolla elsewhere in these
Proceedings, are presented: various measurements of the neutral and charged B
mesons lifetimes, the B^0 mixing frequency, the mistag fractions, and the B -->
D_s^(*) X and B^0 --> D_s^(*)+ D^* branching ratios. Some prospects for the
close future are shown. All the numbers given here are preliminary.

</DOC>
<DOC>
<DOCNO> 151906 </DOCNO>
Noncommutative Tachyons and K-Theory


  We show that the relation between D-branes and noncommutative tachyons leads
very naturally to the relation between D-branes and K-theory. We also discuss
some relations between D-branes and K-homology, provide a noncommutative
generalization of the ABS construction, and give a simple physical
interpretation of Bott periodicity. In addition, a framework for constructing
Neveu-Schwarz fivebranes as noncommutative solitons is proposed.

</DOC>
<DOC>
<DOCNO> 72287 </DOCNO>
Polarized strangeness in the nucleon


  A large violation of the Okubo-Zweig-Iizuka rule was discovered in the
annihilation of stopped antiprotons. The explanation of these experimental data
is discussed in the framework of the model assumed that the nucleon strange sea
quarks are polarized.

</DOC>
<DOC>
<DOCNO> 85586 </DOCNO>
Electrostatic in Reissner-Nordstrom space-time with a conical defect


  We calculate the electrostatic potential generated by a point charge in the
space-time of Reissner-Nordstrom with a conical defect. An expression for the
self-energy is also presented.

</DOC>
<DOC>
<DOCNO> 40549 </DOCNO>
Search for Excited Leptons in e+ e- Interactions at sqrt(s)=192 - 202


  Excited leptons are searched for using the L3 detector at LEP. The data
collected at centre-of-mass energies in the range from 192 up to 202 GeV
correspond to a total luminosity of 233 pb^(-1). No evidence of either pair
production of excited leptons, nor of single production is found. From the
searches for pair produced excited leptons, lower mass limits close to the
kinematic limit are set. From the searches for singly produced excited leptons,
upper limits on their couplings are derived in the mass range up to 200 GeV.

</DOC>
<DOC>
<DOCNO> 123258 </DOCNO>
Presolar Grains from Novae


  We report the discovery of five SiC grains and one graphite grain isolated
from the Murchison carbonaceous meteorite whose major-element isotopic
compositions indicate an origin in nova explosions. The grains are
characterized by low 12C/13C (4-9) and 14N/15N (5-20) ratios, large excesses in
30Si (30Si/28Si ratios range to 2.1 times solar) and high 26Al/27Al ratios.
These isotopic signatures are theoretically predicted for the ejecta from ONe
novae and cannot be matched by any other stellar sources. Previous studies of
presolar grains from primitive meteorites have shown that the vast majority
formed in red giant outflows and supernova ejecta. Although a classical nova
origin was suggested for a few presolar graphite grains on the basis of 22Ne
enrichments, this identification is somewhat ambiguous since it is based only
on one trace element. Our present study presents the first evidence for nova
grains on the basis of major element isotopic compositions of single grains. We
also present the results of nucleosynthetic calculations of classical nova
models and compare the predicted isotopic ratios with those of the grains. The
comparison points toward massive ONe novae if the ejecta are mixed with
material of close-to-solar composition.

</DOC>
<DOC>
<DOCNO> 8539 </DOCNO>
Factorization of correlation functions in coset conformal field theories


  We use the conformal Ward identities to study the structure of correlation
functions in coset conformal field theories. For a large class of primary
fields of arbitrary g/h theory a factorization anzatz is found.Corresponding
correlation functions are explicitly expressed in terms of correlation
functions of two independent WZNW theories for g and h.

</DOC>
<DOC>
<DOCNO> 123222 </DOCNO>
High frequency peakers. I. The bright sample


  Here we present a sample of sources with convex radio spectra peaking at
frequencies above a few GHz. We call these radio sources High Frequency Peakers
(HFPs). This sample extends to higher turnover frequencies than the samples of
Compact Steep Spectrum (CSS) and GHz Peaked Spectrum (GPS) radio sources. HFPs
are rare due to the strong bias against them caused by their turnover occurring
at frequencies about one order of magnitude higher than in CSS-GPS samples. The
sample has been selected by a comparison between the Green Bank survey (87GB)
at 4.9 GHz and the NRAO VLA Sky Survey (NVSS) at 1.4 GHz. Then the candidates
have been observed with the VLA at 1.365, 1.665, 4.535, 4.985, 8.085, 8.485,
14.96 and 22.46 GHz in order to derive a simultaneous radio spectrum, and
remove variable sources from the sample. The final list of genuine HFP sources
consists of 55 objects with flux density exceeding 300 mJy at 4.9 GHz at the
time of the 87GB observation. Optical identifications are available for 29 of
them; 24 are high redshift quasars, 3 are galaxies (one of them has indeed
broad lines in the optical spectrum) and 2 are BL Lac objects. The remaining
sources are mostly empty fields (17) on the digitised POSS or have uncertain
classification (9).

</DOC>
<DOC>
<DOCNO> 69745 </DOCNO>
Comment on ``Violation of the Greisen-Zatsepin-Kuzmin Cutoff: A Tempest


  In a recent letter [1] with the same title, Farrar and Piran offered an
explanation for the near isotropy of the arrival directions [2] of ultrahigh
energy cosmic rays (UHECRs) and the apparent absence [3] of the so called `GZK
cutoff' in their spectrum around $10^{20}$ eV due to pion photoproduction on
the cosmic background radiation (CMB) that was predicted independently by
Greisen [4] and by Zatsepin and Kuz'min [5]. They suggested that the
extragalactic magnetic fields near the Milky Way are strong enough to deflect
and isotropise the arrival directions of the UHECRs from a few nearby sources
for which their travel time to Earth is shorter than their attenuation time by
pion photoproduction on the CMB. They also estimated that this allows active
galactic nuclei (AGNs) or gamma ray bursts (GRBs) to be the source of the
UHECRs. However, these suggestions are inconsistent with various observations

</DOC>
<DOC>
<DOCNO> 13055 </DOCNO>
Structure and Dynamics of amorphous Silica Surfaces


  We use molecular dynamics computer simulations to study the equilibrium
properties of the surface of amorphous silica. Two types of geometries are
investigated: i) clusters with different diameters (13.5\AA, 19\AA, and
26.5\AA) and ii) a thin film with thickness 29\AA. We find that the shape of
the clusters is independent of temperature and that it becomes more spherical
with increasing size. The surface energy is in qualitative agreement with the
experimental value for the surface tension. The density distribution function
shows a small peak just below the surface, the origin of which is traced back
to a local chemical ordering at the surface. Close to the surface the partial
radial distribution functions as well as the distributions of the bond-bond
angles show features which are not observed in the interior of the systems. By
calculating the distribution of the length of the Si-O rings we can show that
these additional features are related to the presence of two-membered rings at
the surface. The surface density of these structures is around 0.6/nm^2 in good
agreement with experimental estimates. From the behavior of the mean-squared
displacement at low temperatures we conclude that at the surface the cage of
the particles is larger than the one in the bulk. Close to the surface the
diffusion constant is somewhat larger than the one in the bulk and with
decreasing temperature the relative difference grows. The total vibrational
density of states at the surface is similar to the one in the bulk. However, if
only the one for the silicon atoms is considered, significant differences are
found.

</DOC>
<DOC>
<DOCNO> 102684 </DOCNO>
A Relation Between the Knizhnik-Zamolodchikov and


  It is shown that Fourier-Laplace transform of the KZ equations for
correlators of the SU(2) WZNW model with respect to auxiliary variables yields
the BPZ equations for correlators of the minimal model of conformal field
theory. This fact is an example at the level of correlators of the relation
between the two models given by the quantum Hamiltonian reduction.

</DOC>
<DOC>
<DOCNO> 101177 </DOCNO>
Sextics with singular points in special position


  In this paper we show a Zariski pair of sextics which is not a degeneration
of the original example given by Zariski. This is the first example of this
kind known. The two curves of the pair have a trivial Alexander polynomial. The
difference in the topology of their complements can only be detected via finer
invariants or techniques. In our case the generic braid monodromies, the
fundamental groups, the characteristic varieties and the existence of dihedral
coverings of $\PP^2$ ramified along them can be used to distinguish the two
sextics. Our intention is not only to use different methods and give a general
description of them but also to bring together different perspectives of the
same problem.

</DOC>
<DOC>
<DOCNO> 13300 </DOCNO>
Sharp interface limits of phase-field models


  The use of continuum phase-field models to describe the motion of
well-defined interfaces is discussed for a class of phenomena, that includes
order/disorder transitions, spinodal decomposition and Ostwald ripening,
dendritic growth, and the solidification of eutectic alloys. The projection
operator method is used to extract the ``sharp interface limit'' from phase
field models which have interfaces that are diffuse on a length scale $\xi$. In
particular,phase-field equations are mapped onto sharp interface equations in
the limits $\xi \kappa \ll 1$ and $\xi v/D \ll 1$, where $\kappa$ and $v$ are
respectively the interface curvature and velocity and $D$ is the diffusion
constant in the bulk. The calculations provide one general set of sharp
interface equations that incorporate the Gibbs-Thomson condition, the
Allen-Cahn equation and the Kardar-Parisi-Zhang equation.

</DOC>
<DOC>
<DOCNO> 11553 </DOCNO>
Persistent edge currents for paired quantum hall states


  We study the behavior of the persistent edge current for paired quantum Hall
states on the cylinder. We show that the currents are periodic with the unit
flux $\phi_0=hc/e$. At low temperatures, they exhibit anomalous oscillations in
their flux dependence.The shape of the functions converges to the sawtooth
function periodic with $\phi_0/2$.

</DOC>
<DOC>
<DOCNO> 118273 </DOCNO>
Improving the Resolution of X-Ray Telescopes with Occulting Satellites


  One of the challenges of X-ray astronomy is how to both collect large numbers
of photons yet attain high angular resolution. Because X-ray telescopes utilize
grazing optics, to collect more photons requires a larger acceptance angle
which in turn compromises the angular resolution. All X-ray telescopes thus
have angular resolution far poorer than their diffraction limit. Although
collecting more photons is a desirable goal, sometimes selective collecting
fewer photons may yield more information. Natural (such as lunar) occultations
have long been used to study sources on small angular scales. But natural
occulters are of limited utility because of their large angular velocities
relative to the telescope, and because of the serendipity of their transits. We
describe here how one can make use of an X-ray Big Occulting Steerable
Satellite (X-BOSS) to achieve very-high resolution of X-ray sources. An X-BOSS
could significantly improve the resolution of existing X-ray facilities such as
the Chandra telescope, or X-ray Multiple Mirror (XMM) satellite, and could
vastly improve the resolution of some future X-ray telescopes, particularly
Constellation X where sub-milliarcsecond resolution is possible for a wide
range of sources. Similar occulting satellites could also be deployed in
conjunction with planned space observatories for other wavebands.

</DOC>
<DOC>
<DOCNO> 85651 </DOCNO>
E_(10), BE_(10) and Arithmetical Chaos in Superstring Cosmology


  It is shown that the never ending oscillatory behaviour of the generic
solution, near a cosmological singularity, of the massless bosonic sector of
superstring theory can be described as a billiard motion within a simplex in
9-dimensional hyperbolic space. The Coxeter group of reflections of this
billiard is discrete and is the Weyl group of the hyperbolic Kac-Moody algebra
E$_{10}$ (for type II) or BE$_{10}$ (for type I or heterotic), which are both
arithmetic. These results lead to a proof of the chaotic (``Anosov'') nature of
the classical cosmological oscillations, and suggest a ``chaotic quantum
billiard'' scenario of vacuum selection in string theory.

</DOC>
<DOC>
<DOCNO> 116554 </DOCNO>
Quantum Gravity


  Gravitons should have momentum just as photons do; and since graviton
momentum would cause compression rather than elongation of spacetime outside of
matter; it does not appear that gravitons are compatible with Swartzchild's
spacetime curvature. Also, since energy is proportional to mass, and mass is
proportional to gravity; the energy of matter is proportional to gravity. The
energy of matter could thus contract space within matter; and because of the
inter-connectedness of space, cause the elongation of space outside of matter.
And this would be compatible with Swartzchild spacetime curvature. Since
gravity could be initiated within matter by the energy of mass, transmitted to
space outside of matter by the inter-connectedness of space; and also
transmitted through space by the same inter-connectedness of space; and since
spatial and relativistic gravities can apparently be produced without the aid
of gravitons; massive gravity could also be produced without gravitons as well.
  Gravity divided by an infinite number of segments would result in zero
expression of gravity, because it could not curve spacetime. So spatial
segments must have a minimum size, which is the Planck length; thus resulting
in quantized space. And since gravity is always expressed over some distance in
space, quantum space would therefore always quantize gravity. So the
non-mediation of gravity by gravitons does not result in unquantized gravity,
because quantum space can quantize gravity; thus making gravitons unproven and
unnecessary, and explaining why gravitons have never been found.

</DOC>
<DOC>
<DOCNO> 70154 </DOCNO>
Impact of e^+ and e^- Beam Polarization on Chargino and Neutralino


  We study the production processes e^+ e^- -> chi^+_i chi^-_j, i,j=1,2, and
e^+ e^- -> chi^0_m chi^0_n, m,n=1,...,4, working out the advantages of
polarizing both beams. For e^+ e^- -> chi^+_1 chi^-_1 with chi^-_1 -> chi^0_1
e^- nu and e^+ e^- -> chi^0_1 chi^0_2 with chi^0_2 -> chi^0_1 e^+ e^- we
perform a detailed analysis, including the complete spin correlations between
production and decay. We analyze the forward--backward asymmetry of the decay
electron for various beam polarizations. We also study polarization asymmetries
in e^+ e^- -> chi^0_1 chi^0_2. These asymmetries strongly constrain the gaugino
parameter M_1 and the masses m_{\tilde{e}_L}, m_{\tilde{e}_R}, m_{\tilde{nu}}
also if m_{\tilde{e}_{L,R}}, m_{\tilde{nu}} > sqrt{s}/2. We give numerical
predictions for three scenarios for a linear collider with sqrt{s}=500-1000
GeV.

</DOC>
<DOC>
<DOCNO> 84486 </DOCNO>
Negative Energies on the Brane


  It has recently been proposed that our universe is a three-brane embedded in
a higher dimensional spacetime. Here I show that black holes on the brane,
black strings intersecting the brane, and gravitational waves propagating in
the bulk induce an effective energy-momentum tensor on the brane that contains
negative energy densities.

</DOC>
<DOC>
<DOCNO> 122231 </DOCNO>
A NICMOS imaging study of high-z quasar host galaxies


  We present the first results from a major Hubble Space Telescope program
designed to investigate the cosmological evolution of quasar host galaxies from
z~2 to the present day. Here we describe J and H-band NICMOS imaging of two
quasar samples at redshifts of 0.9 and 1.9 respectively. Each sample contains
equal numbers of radio-loud and radio-quiet quasars, selected to lie within the
same narrow range of optical absolute magnitude (-24 > M_V > -25). Filter and
target selection were designed to ensure that at each redshift the images
sample the same part of the object's rest-frame spectrum, avoiding potential
contamination by [OIII]lambda5007 and H-alpha emission lines. At z=1 the hosts
of both radio-loud and radio-quiet quasars lie on the same Kormendy relation
described by 3CR radio galaxies at comparable redshift. There is some evidence
for a gap of ~1 mag between the host luminosities of RLQs and RQQs, a
difference that cannot be due to emission-line contamination given the design
of our study. However, within current uncertainties, simple passive stellar
evolution is sufficient to link these galaxies with the elliptical hosts of
low-redshift quasars of comparable nuclear output, implying that the hosts are
virtually fully assembled by z=1. At z=2 the luminosity gap appears to have
widened further to ~1.5 mag. Thus while the hosts of radio-loud quasars remain
consistent with a formation epoch of z>3, allowing for passive evolution
implies that the hosts of radio-quiet quasars are ~2-4 times less massive at
z=2 than at low z.

</DOC>
<DOC>
<DOCNO> 9225 </DOCNO>
d-wave pairing symmetry in cuprate superconductors


  Phase-sensitive tests of pairing symmetry have provided strong evidence for
predominantly d-wave pairing symmetry in both hole- and electron-doped high-Tc
cuprate superconductors. Temperature dependent measurements in YBCO indicate
that the d-wave pairing dominates, with little if any imaginary component, at
all temperatures from 0.5K through Tc. In this article we review some of this
evidence and discuss the implications of the universal d-wave pairing symmetry
in the cuprates.

</DOC>
<DOC>
<DOCNO> 9875 </DOCNO>
Effective action of a compressible QH state edge: application to


  The electrodynamical response of the edge of a compressible Quantum Hall
system affects tunneling into the edge. Using the composite Fermi liquid
theory, we derive an effective action for the edge modes interacting with
tunneling charge. This action generalizes the chiral Luttinger liquid theory of
the Quantum Hall edge to compressible systems in which transport is
characterized by a finite Hall angle. In addition to the standard terms, the
action contains a dissipative term. The tunneling exponent is calculated as a
function of the filling fraction for several models, including short-range and
long-range Coulomb interaction. We find that tunneling exponents are robust and
to a large extent insensitive to the particular model.
  We discuss recent tunneling measurements in the overgrown cleaved edge
systems, and demonstrate that the profile of charge density near the edge is
very sensitive to the parameters of the system. In general, the density is
non-monotonic, and can deviate from the bulk value by up to 30%. Implications
for the correspondence to the chiral Luttinger edge theories are discussed.

</DOC>
<DOC>
<DOCNO> 70741 </DOCNO>
Searching for Anomalous Higgs Couplings in Peripheral Heavy Ion


  We investigate the sensitivity of the heavy ion mode of the LHC to anomalous
Higgs boson couplings to photons, H-photon-photon, through the analysis of the
processes photon photon to b anti-b and photon photon to photon photon in
peripheral heavy ion collisions. We suggest cuts to improve the signal over
background ratio and determine the capability of LHC to impose bounds on
anomalous couplings by searching for a Higgs boson signal in these modes.

</DOC>
<DOC>
<DOCNO> 12784 </DOCNO>
The Ising Like Statistical Models for Studying the Dynamics of the


  In this paper, we present the possibility of using the Ising like models to
explain by Statistical Physics means the connection between the financial
discontinuities (herd behavior, bubbles, crashes) and "critical points" in
physical of phase transitions due to cooperative effects. For this purpose
there are investigated 1/2 and 3/2 Ising like spin models which involve one or
more macroscopical order parameters, which can have nonanlitical behavior in
the critical domain.

</DOC>
<DOC>
<DOCNO> 12577 </DOCNO>
Current-voltage characteristics of the two-dimensional XY model with


  Current-voltage characteristics and the linear resistance of the
two-dimensional XY model with and without external uniform current driving are
studied by Monte Carlo simulations. We apply the standard finite-size scaling
analysis to get the dynamic critical exponent $z$ at various temperatures. From
the comparison with the resistively-shunted junction dynamics, it is concluded
that $z$ is universal in the sense that it does not depend on details of
dynamics. This comparison also leads to the quantification of the time in the
Monte Carlo dynamic simulation.

</DOC>
<DOC>
<DOCNO> 169859 </DOCNO>
Towards Nonadditive Quantum Information Theory


  A definition of the nonadditive (nonextensive) conditional entropy indexed by
q is presented. Based on the composition law in terms of it, the
Shannon-Khinchin axioms are generalized and the uniqueness theorem is
established for the Tsallis entropy. The nonadditive conditional entropy, when
considered in the quantum context, is always positive for separable states but
takes negative values for entangled states, indicating its utility for
characterizing entanglement. A criterion deduced from it for separability of
the density matrix is examined in detail by using a bipartite spin-half system.
It is found that the strongest criterion for separability obtained by Peres
using an algebraic method is recovered in the present information-theoretic
approach.

</DOC>
<DOC>
<DOCNO> 83349 </DOCNO>
The Bisimulation Problem for equational graphs of finite out-degree


  The "bisimulation problem" for equational graphs of finite out-degree is
shown to be decidable. We reduce this problem to the bisimulation problem for
deterministic rational (vectors of) boolean series on the alphabet of a dpda M.
We then exhibit a complete formal system for deducing equivalent pairs of such
vectors.

</DOC>
<DOC>
<DOCNO> 118482 </DOCNO>
Capture of alpha Particles by Isospin-Symmetric Nuclei


  The reaction rates for alpha capture processes on self-conjugate nuclei in
the mass range A=20-40 have been investigated. The rates were calculated using
the statistical model code NON-SMOKER taking into account isospin suppression
rules. These theoretical predictions are compared with rates derived from the
available experimental data about the alpha capture reactions taking also into
account additional experimental information from different reaction channels
populating the alpha unbound states of the self-conjugate compound nuclei.

</DOC>
<DOC>
<DOCNO> 85596 </DOCNO>
Rotating Hairy Black Holes


  We construct stationary black holes in SU(2) Einstein-Yang-Mills theory,
which carry angular momentum and electric charge. Possessing non-trivial
non-abelian magnetic fields outside their regular event horizon, they represent
non-perturbative rotating hairy black holes.

</DOC>
<DOC>
<DOCNO> 69482 </DOCNO>
The renormalization group for correlated scales: one-stage versus


  Nonrelativistic bound states have two low energy scales, a soft scale mu_S of
order mv and an ultrasoft scale mu_U of order mv^2. In two-stage running, the
soft and ultrasoft scales are lowered from m to mv, and then the ultrasoft
scale is lowered from mv to mv^2. In one-stage running, the two scales are
lowered in a correlated way using a subtraction velocity. We compare these two
methods of summing logarithms and show that only the correlated running in
velocity space of the one-stage method correctly reproduces the logarithms in
non-relativistic bound states in QED. The argument for one-stage running is
general, and should apply to any system with correlated scales.

</DOC>
<DOC>
<DOCNO> 69641 </DOCNO>
High-Energy Scattering and Diffraction: Theory Summary


  New developments in the theory and phenomenology of high-energy scattering
and diffraction that were presented and discussed at DIS2000 are reviewed.

</DOC>
<DOC>
<DOCNO> 102334 </DOCNO>
Une formule de Plancherel pour l'alg`ebre de Hecke d'un groupe r'eductif


  We show a matrix Paley-Wiener theorem for the Hecke algebra of a p-adic
group. The proof is based on an analogue of Harish-Chandra's Plancherel
formula.

</DOC>
<DOC>
<DOCNO> 70131 </DOCNO>
Quantum Cosmology and AdS/CFT


  In this paper we study the creation of brane-worlds in $AdS$ bulk. We first
consider the simplest case of onebranes in $AdS_3$. In this case we are able to
properly describe the creation of a spherically symmetric brane-world deriving
a general expression for its wavefunction. Then, we sketch the $AdS_{d+1}$
set-up within the context of the WKB approximation. Finally, we comment on
these scenarios in light of the $AdS/CFT$ correspondence.

</DOC>
<DOC>
<DOCNO> 150841 </DOCNO>
The U(1)s in the Finite N Limit of Orbifold Field Theories


  We study theories generated by orbifolding the {\cal N}=4 super conformal
U(N) Yang Mills theory with finite N, focusing on the r\^ole of the remnant
U(1) gauge symmetries of the orbifold process. It is well known that the one
loop beta functions of the non abelian SU(N) gauge couplings vanish in these
theories. It is also known that in the large N limit the beta functions vanish
to all order in perturbation theory. We show that the beta functions of the non
abelian SU(N) gauge couplings vanish to two and three loop order even for
finite N. This is the result of taking the abelian U(1) of U(N)=SU(N)xU(1) into
account. However, the abelian U(1) gauge couplings have a non vanishing beta
function. Hence, those theories are not conformal for finite N. We analyze the
renormalization group flow of the orbifold theories, discuss the suppression of
the cosmological constant and tackle the hierarchy problem in the non
supersymmetric models.

</DOC>
<DOC>
<DOCNO> 84170 </DOCNO>
Mesoscopic Fluctuations in Stochastic Spacetime


  Mesoscopic effects associated with wave propagation in spacetime with metric
stochasticity are studied. We show that the scalar and spinor waves in a
stochastic spacetime behave similarly to the electrons in a disordered system.
Viewing this as the quantum transport problem, mesoscopic fluctuations in such
a spacetime are discussed. The conductance and its fluctuations are expressed
in terms of a nonlinear sigma model in the closed time path formalism. We show
that the conductance fluctuations are universal, independent of the volume of
the stochastic region and the amount of stochasticity.

</DOC>
<DOC>
<DOCNO> 67746 </DOCNO>
phi -> pi0 pi0 gamma Decay within a U(3)x U(3) Linear Sigma Model


  We show that therecently observed pion invariant mass distribution of the phi
->pi0 pi0 gamma decay can be satisfactorily described by the chiral U(3) X U(3)
Linear Sigma Model.

</DOC>
<DOC>
<DOCNO> 12072 </DOCNO>
Few comments on preprint cond-mat/0007430 by Aleiner et al


  A few comments are made on the recent preprint cond-mat/0007430 by Aleiner et
al. We show that the results presented there heavily rely on the assumption of
perfect electron-hole symmetry breaking and once we drop this assumption we
find a Kondo temperature in the experimentally accessible range.

</DOC>
<DOC>
<DOCNO> 12803 </DOCNO>
Optimization with Extremal Dynamics


  We explore a new general-purpose heuristic for finding high-quality solutions
to hard optimization problems. The method, called extremal optimization, is
inspired by self-organized criticality, a concept introduced to describe
emergent complexity in physical systems. Extremal optimization successively
replaces extremely undesirable variables of a single sub-optimal solution with
new, random ones. Large fluctuations ensue, that efficiently explore many local
optima. With only one adjustable parameter, the heuristic's performance has
proven competitive with more elaborate methods, especially near phase
transitions which are believed to coincide with the hardest instances. We use
extremal optimization to elucidate the phase transition in the 3-coloring
problem, and we provide independent confirmation of previously reported
extrapolations for the ground-state energy of +-J spin glasses in d=3 and 4.

</DOC>
<DOC>
<DOCNO> 68471 </DOCNO>
Two-loop dimensional reduction and effective potential without


  In many extensions of the Standard Model, finite temperature computations are
complicated by a hierarchy of zero temperature mass scales, in addition to the
usual thermal mass scales. We extend the standard thermal resummations to such
a situation, and discuss the 2-loop computations of the Higgs effective
potential, and an effective 3d field theory for the electroweak phase
transition, without carrying out high or low temperature expansions for the
heavy masses. We also estimate the accuracy of the temperature expansions
previously used for the MSSM electroweak phase transition in the presence of a
heavy left-handed stop. We find that the low temperature limit of dealing with
the left-handed stop is accurate up to surprisingly high temperatures.

</DOC>
<DOC>
<DOCNO> 174523 </DOCNO>
Scaling of Particle and Transverse Energy Production in 208Pb+208Pb


  Transverse energy, charged particle pseudorapidity distributions and photon
transverse momentum spectra have been studied as a function of the number of
participants (N_{part}) and the number of binary nucleon-nucleon collisions
(N_{coll}) in 158 A GeV Pb+Pb collisions over a wide impact parameter range. A
scaling of the transverse energy pseudorapidity density at midrapidity as
N_{part}^{1.08 \pm 0.06} and N_{coll}^{0.83 \pm 0.05} is observed. For the
charged particle pseudorapidity density at midrapidity we find a scaling as
N_{part}^{1.07 \pm 0.04} and N_{coll}^{0.82 \pm 0.03}. This faster than linear
scaling with N_{part} indicates a violation of the naive Wounded Nucleon Model.

</DOC>
<DOC>
<DOCNO> 170038 </DOCNO>
Orthogonality relations in Quantum Tomography


  Quantum estimation of the operators of a system is investigated by analyzing
its Liouville space of operators. In this way it is possible to easily derive
some general characterization for the sets of observables (i.e. the possible
quorums) that are measured for the quantum estimation. In particular we analyze
the reconstruction of operators of spin systems.

</DOC>
<DOC>
<DOCNO> 118285 </DOCNO>
A vestige low metallicity gas shell surrounding the radio galaxy


  Observations are presented showing the doublet CIV 1550 absorption lines
superimposed on the CIV emission in the radio galaxy 0943-242. Within the
errors, the redshift of the absorption system that has a column density of
N_CIV = 10^{14.5 +- 0.1} cm-2 coincides with that of the deep Ly-alpha
absorption trough observed by Rottgering et al. (1995). The gas seen in
absorption has a resolved spatial extent of at least 13 kpc (the size of the
extended emission line region). We first model the absorption and emission gas
as co-spatial components with the same metallicity and degree of excitation.
Using the information provided by the emission and absorption line ratios of
CIV and Ly-alpha, we find that the observed quantities are incompatible with
photoionization or collisional ionization of cloudlets with uniform properties.
We therefore reject the possibility that the absorption and emission phases are
co-spatial and favour the explanation that the absorption gas has low
metallicity and is located further away from the host galaxy (than the emission
line gas). The estimated low metallicity for the absorption gas in 0943-242 (Z
\~ 1% solar) and its proposed location -outer halo outside the radio cocoon-
suggest that its existence preceeds the observed AGN phase and is a vestige of
the initial starburst at the onset of formation of the parent galaxy.

</DOC>
<DOC>
<DOCNO> 13398 </DOCNO>
Algebraic Geometry and Physics


  This article is an interdisciplinary review and an on-going progress report
over the last few years made by myself and collaborators in certain fundamental
subjects on two major theoretic branches in mathematics and theoretical
physics: algebraic geometry and quantum physics. I shall take a practical
approach, concentrating more on explicit examples rather than formal
developments. Topics covered are divided in three sections: (I) Algebraic
geometry on two-dimensional exactly solvable statistical lattice models and its
related Hamiltonians: I will report results on the algebraic geometry of
rapidity curves appeared in the chiral Potts model, and the algebraic Bethe
Ansatz equation in connection with quantum inverse scattering method for the
related one-dimensional Hamiltonion chain, e.g., XXZ, Hofstadter type
Hamiltonian. (II) Infinite symmetry algebras arising from quantum spin chain
and conformal field theory: I will explain certain progress made on Onsager
algebra, the relation with the superintegrable chiral Potts quantum chain and
problems on its spectrum. In conformal field theory, mathematical aspects of
characters of N=2 superconformal algebra are discussed, especially on the
modular invariant property connected to the theory. (III). Algebraic geometry
problems on orbifolds stemming from string theory: I will report recent
progress on crepant resolutions of quotient singularity of dimension greater
than or equal to three. The direction of present-day research of engaging
finite group representations in the geometry of orbifolds is briefly reviewed,
and the mathematical aspect of various formulas on the topology of string
vacuum will be discussed.

</DOC>
<DOC>
<DOCNO> 13528 </DOCNO>
Surface soft phonon and the root3 x root3 <--> 3 x 3 phase transition in


  Density Functional Theory (DFT) calculations show that the reversible
Sn/Ge(111) $\sqrt{3}\times\sqrt{3} \leftrightarrow 3\times3$ phase transition
can be described in terms of a surface soft phonon. The isovalent Sn/Si(111)
case does not display this transition since the $\sqrt{3}\times\sqrt{3}$ phase
is the stable structure at low temperature, although it presents a partial
softening of the $3\times3$ surface phonon. The rather flat energy surfaces for
the atomic motion associated with this phonon mode in both cases explain the
experimental similarities found at room temperature between these systems. The
driving force underlying the $\sqrt{3}\times\sqrt{3} \leftrightarrow 3\times3$
phase transition is shown to be associated with the electronic energy gain due
to the Sn dangling bond rehybridization.

</DOC>
<DOC>
<DOCNO> 101766 </DOCNO>
The surjectivity problem for one-generator,, one-relator extensions of


  We use Klyachko's methods to prove that the natural map G to G-hat, where G
is a torsion-free group and G-hat is obtained by adding a new generator t and a
new relator w, is surjective only if w is conjugate to gt or gt^{-1} for some g
in G. This solves a special case of the surjectivity problem for group
extensions, raised by Cohen [Whitehead torsion, group extensions, and Zeeman's
conjecture in high dimensions, Topology, 16 (1977) 79--88].

</DOC>
<DOC>
<DOCNO> 39745 </DOCNO>
Detecting the (Quasi-)Two-Body Decays of $\tau$ Leptons in


  Novel detector schemes are proposed for the short-baseline neutrino
experiments of next generation, aimed at exploring the large-$\Delta m^2$
domain of \omutau oscillations in the appearance mode. These schemes emphasize
good spectrometry for charged particles and for electromagnetic showers and
efficient reconstruction of \ypi_gg decays. The basic elements are a sequence
of relatively thin emulsion targets, immersed in magnetic field and
interspersed with electronic trackers, and a fine-grained electromagnetic
calorimeter built of lead glass. These elements act as an integral whole in
reconstructing the electromagnetic showers. This conceptual scheme shows good
performance in identifying the $\tau$ (quasi-)two-body decays by their
characteristic kinematics and in selecting the electronic decays of the $\tau$.

</DOC>
<DOC>
<DOCNO> 170060 </DOCNO>
The information interpretation of quantum mechanics


  In the information interpretation of quantum mechanics, information is the
most fundamental, basic entity. Every quantized system is associated with a
definite discrete amount of information (cf. Zeilinger). This information
content remains constant at all times and is permutated one-to-one throughout
the system evolution. What is interpreted as measurement is a particular type
of information transfer over a fictitious interface. The concept of a
many-to-one state reduction is not a fundamental one but results from the
practical impossibility to reconstruct the original state after the
measurement.

</DOC>
<DOC>
<DOCNO> 122777 </DOCNO>
The globular cluster system of the young elliptical NGC 6702


  We study the globular cluster (GC) system of the dust-lane elliptical galaxy
NGC 6702, using B, V and I-band photometric observations carried out at the
Keck telescope. This galaxy has a spectroscopic age of ~2Gyrs suggesting recent
star-formation. We find strong evidence for a bimodal GC colour distribution,
with the blue peak having a colour similar to that of the Galactic halo GCs.
Assuming that the blue GCs are indeed old and metal-poor, we estimate an age of
2-5Gyrs and supersolar metallicity for the red GC subpopulation. Despite the
large uncertainties, this is in reasonable agreement with the spectroscopic
galaxy age. Additionally, we estimate a specific frequency of S_{N}=2.3\pm1.1
for NGC 6702. We predict that passive evolution of NGC 6702 will further
increase its specific frequency to S_{N}~2.7 within 10Gyrs, in closer agreement
to that of typical present-day ellipticals. We also discuss evidence that the
merger/accretion event that took place a few Gyrs ago involved a high gas
fraction.

</DOC>
<DOC>
<DOCNO> 68555 </DOCNO>
Black holes on the brane


  We consider exact solutions for static black holes localized on a three-brane
in five-dimensional gravity in the Randall-Sundrum scenario. We show that the
Reissner-Nordstrom metric is an exact solution of the effective Einstein
equations on the brane, re-interpreted as a black hole without electric charge,
but with instead a tidal 'charge' arising via gravitational effects from the
fifth dimension. The tidal correction to the Schwarzschild potential is
negative, which is impossible in general relativity, and in this case only one
horizon is admitted, located outside the Schwarzschild horizon. The solution
satisfies a closed system of equations on the brane, and describes the
strong-gravity regime. Current observations do not strongly constrain the tidal
charge, and significant tidal corrections could in principle arise in the
strong-gravity regime and for primordial black holes.

</DOC>
<DOC>
<DOCNO> 68512 </DOCNO>
From Black Holes to Pomeron: Tensor Glueball and Pomeron Intercept at


  We briefly review the approach for strong coupling calculation of glueball
masses based on the duality between supergravity and Yang-Mills theory. Earlier
work is extended to non-zero spin. Fluctuations in the gravitational metric
lead to the $2^{++}$ tensor glueball state on the leading Pomeron trajectory
with a mass relation: $m(0^{++}) < m(2^{++}) $. In particular, for $QCD_4$, a
strong coupling expansion for the Pomeron intercept is obtained.

</DOC>
<DOC>
<DOCNO> 116831 </DOCNO>
Discrete solvent effects on the effective interaction between charged


  Using computer simulations of two charged colloidal spheres with their
counterions in a hard sphere solvent, we show that the granular nature of the
solvent significantly influences the effective colloidal interaction. For
divalent counterions, the total effective force can become attractive generated
by counterion hydration, while for monovalent counterions the forces are
repulsive and well-described by a solvent-induced colloidal charge
renormalization. Both effects are not contained in the traditional "primitive"
approaches but can be accounted for in a solvent-averaged primitive model.

</DOC>
<DOC>
<DOCNO> 68680 </DOCNO>
Emergence of Skyrme crystal in Gross-Neveu and 't Hooft models at finite


  We study two-dimensional, large $N$ field theoretic models (Gross-Neveu
model, 't Hooft model) at finite baryon density near the chiral limit. The same
mechanism which leads to massless baryons in these models induces a breakdown
of translational invariance at any finite density. In the chiral limit baryonic
matter is characterized by a spatially varying chiral angle with a wave number
depending only on the density. For small bare quark masses a sine-Gordon kink
chain is obtained which may be regarded as simplest realization of the Skyrme
crystal for nuclear matter. Characteristic differences between confining and
non-confining models are pointed out.

</DOC>
<DOC>
<DOCNO> 10410 </DOCNO>
Self-consistent description of simplified pseudospin-electron model


  A method of the self-consistent calculation of the thermodynamical and
correlation functions is presented.
 This approach is based on the GRPA (generalized random phase approximation)
scheme with the inclusion of the mean field corrections.
 The numerical research shows that interaction between the electron and
pseudospin subsystems leads to the possibility of the dipole (pseudospin) and
charge-density instabilities as well as phase separation into the uniform
and/or chess-board phases.

</DOC>
<DOC>
<DOCNO> 169864 </DOCNO>
Interference-induced gain in Autler-Townes doublet of a V-type atom in a


  We study the Autler-Townes spectrum of a V-type atom coupled to a
single-mode, frequency-tunable cavity field at finite termperature, with a
pre-selected polarization in the bad cavity limit, and show that, when the mean
number of thermal photons $N\gg 1$ and the excited sublevel splitting is very
large (the same order as the cavity linewidth), the probe gain may occur at
either sideband of the doublet, depending on the cavity frequency, due to the
cavity-induced interference.

</DOC>
<DOC>
<DOCNO> 70534 </DOCNO>
A Lower Bound on sin 2\beta from Minimal Flavour Violation


  We point out that there exists an absolute lower bound on sin 2\beta in all
models with minimal flavour violation (MFV), that do not have any new operators
beyond those present in the Standard Model and in which all flavour changing
transitions are governed by the CKM matrix with no new phases beyond the KM
phase. This bound depends only on V_{cb}, V_{ub} and the hadronic parameters
\hat B_K, F_{B_d}\sqrt{\hat B_d} and \xi relevant for the CP-violating
parameter \varepsilon and the B^0_{d,s}-\bar B^0_{d,s} mixings. Performing a
simple scanning over the present ranges of these parameters we find sin
2\beta\ge 0.34. We illustrate how this bound could become stronger when our
knowledge of the parameters in question improves and when the upper bound on
the B^0_{s}-\bar B^0_{s} mixing ((\Delta M)_s) will be experimentally known.
Provided the future accurate measurements of sin 2\beta through the CP
asymmetry in B_d^0(\bar B_d^0)\to \psi K_S will confirm the low values recently
reported by BaBar and Belle, there is a likely possibility that this class of
models will be excluded. This would firmly imply the necessity of new
CP-violating phases and/or new effective operators in the weak effective
Hamiltonians for K^0-\bar K^0 and B^0_{d,s}-\bar B^0_{d,s} mixings. We also
point out that within the MFV models there exists also an absolute lower bound
on the angle \gamma. We find \sin\gamma\ge 0.24. This lower bound could become
stronger in the future.

</DOC>
<DOC>
<DOCNO> 169946 </DOCNO>
Fluctuation, Dissipation, and Entanglement: the Classical and Quantum


  A general theory of thermal magnetic fluctuations near conductive materials
is developed; such fluctuations are the magnetic analog of Johnson noise. For
realistic experiments in quantum computing and magnetic resonance force
microscopy, the predicted relaxation can be rapid enough that substantial
experimental care should be taken to minimize it. The same Hamiltonian matrix
elements that govern fluctuation and dissipation are shown to also govern
entanglement and renormalization, and a specific example of a
fluctuation-dissipation-entanglement theorem is constructed.

</DOC>
<DOC>
<DOCNO> 117258 </DOCNO>
Angular momentum spatial distribution symmetry breaking in Rb by an


  Excited state angular momentum alignment -- orientation conversion for atoms
with hyperfine structure in presence of an external magnetic field is
investigated. Transversal orientation in these conditions is reported for the
first time. This phenomenon occurs under Paschen Back conditions at
intermediate magnetic field strength. Weak radiation from a linearly polarized
diode laser is used to excite Rb atoms in a cell. The laser beam is polarized
at an angle of pi/4 with respect to the external magnetic field direction.
Ground state hyperfine levels of the 5S_1/2 state are resolved using
laser-induced fluorescence spectroscopy under conditions for which all excited
5P_3/2 state hyperfine components are excited simultaneously. Circularly
polarized fluorescence is observed to be emitted in the direction perpendicular
to both to the direction of the magnetic field B and direction of the light
polarization E. The obtained circularity is shown to be in quantitative
agreement with theoretical predictions.

</DOC>
<DOC>
<DOCNO> 80960 </DOCNO>
Benchmarking MILC code with OpenMP and MPI


  A trend in high performance computers that is becoming increasingly popular
is the use of symmetric multiprocessing (SMP) rather than the older paradigm of
MPP. MPI codes that ran and scaled well on MPP machines can often be run on an
SMP machine using the vendor's version of MPI. However, this approach may not
make optimal use of the (expensive) SMP hardware. More significantly, there are
machines like Blue Horizon, an IBM SP with 8-way SMP nodes at the San Diego
Supercomputer Center that can only support 4 MPI processes per node (with the
current switch). On such a machine it is imperative to be able to use OpenMP
parallelism on the node, and MPI between nodes. We describe the challenges of
converting MILC MPI code to using a second level of OpenMP parallelism, and
benchmarks on IBM and Sun computers.

</DOC>
<DOC>
<DOCNO> 10687 </DOCNO>
c-axis penetration depth in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ single


  The $c$-axis penetration depth $\Delta\lambda_c$ in
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ (BSCCO) single crystals as a function of
temperature has been determined using two techniques, namely, measurements of
the ac-susceptibility at a frequency of 100 kHz and the surface impedance at
9.4 GHz. Both techniques yield an almost linear function
$\Delta\lambda_c(T)\propto T$ in the temperature range T<0.5 T_c.
Electrodynamic analysis of the impedance anisotropy has allowed us to estimate
$\lambda_c(0)\approx 50 \mu$m in BSCCO crystals overdoped with oxygen
($T_c\approx 84$ K) and $\lambda_c(0)\approx 150 \mu$m at the optimal doping
level ($T_c\approx 90$ K).

</DOC>
<DOC>
<DOCNO> 10973 </DOCNO>
Bose-Einstein condensation in the presence of an impurity


  It is shown that Bose-Einstein condensation occurs for an ideal gas in two
spatial dimensions in the presence of one impurity which is described quantum
mechanically in terms of a point-like vortex and a contact interaction. This
model is exactly solvable and embodies as a special case the analogous problem
in three spatial dimensions.

</DOC>
<DOC>
<DOCNO> 85001 </DOCNO>
Spin group and almost commutative geometry


  For Connes' spectral triples, the group of automorphisms lifted to the
Hilbert space is defined and used to fluctuate the metric. A few commutative
examples are presented including Chamseddine and Connes' spectral unification
of gravity and electromagnetism. One almost commutative example is treated: the
full standard model. Here the lifted automorphisms explain O'Raifeartaigh's
reduction $SU(2)\times U(3)/\zz_2.$

</DOC>
<DOC>
<DOCNO> 152028 </DOCNO>
On Finite Matrix Bi-Dimensional Formulation of $D=4n+2$ Classical Field


  We introduce a basis for a bi-dimensional finite matrix calculus and a
bi-dimensional finite matrix action principle. As an application, we analyze
scalar and spinorial fields in $D=4n+2$ in this approach. We verify that to
establish a bi-dimensional matrix action principle we have to define a
Dirac-algebra-modified Lebniz rule. From the bi-dimensional equations of
motion, we obtain a matrix holomorphic feature for massless matrix scalar and
spinorial fields.

</DOC>
<DOC>
<DOCNO> 102029 </DOCNO>
A Classification and Examples of Four-Dimensional Isoclinic Three-Webs


  A classification and examples of four-dimensional isoclinic three-webs of
codimension two are given. The examples considered prove the existence theorem
for many classes of webs for which the general existence theorems are not
proved yet.

</DOC>
<DOC>
<DOCNO> 100892 </DOCNO>
Rolling Factors Deformations and Extensions of Canonical Curves


  A tetragonal canonical curve is the complete intersection of two divisors on
a scroll. The equations can be written in `rolling factors' format. For such
homogeneous ideals we give methods to compute infinitesimal deformations.
Deformations can be obstructed. For the case of quadratic equations on the
scroll we derive explicit base equations. They are used to study extensions of
tetragonal curves.

</DOC>
<DOC>
<DOCNO> 69479 </DOCNO>
Leading logarithm calculation of the e^+ e^- -> e^+ \nu_e \bar{u} d


  We analytically evaluate in the leading logarithm approximation the
differential cross section for e^+ e^- -> e^+ \nu_e \bar{u} d. We compare our
order \alpha^4 \alpha_s^0 leading-log result to the order \alpha^4 \alpha_s^0
exact result obtained from the GRC4F Monte Carlo program. Finally we use the
Gluck, Reya, Schienbien distribution of partons in a virtual photon, which
incorporates both evolution and nonperturbative strong interaction
contributions, to obtain better estimates of the differential cross section.

</DOC>
<DOC>
<DOCNO> 40058 </DOCNO>
Prospects for Spin Physics at RHIC


  Colliding beams of 70% polarized protons at up to $\sqrt{s}$=500 GeV, with
high luminosity, L=2$\times10^{{\rm 32}}$ cm$^{-2}$sec$^{-1}$, will represent a
new and unique laboratory for studying the proton. RHIC-Spin will be the first
polarized-proton collider and will be capable of copious production of jets,
directly produced photons, and $W$ and $Z$ bosons. Features will include direct
and precise measurements of the polarization of the gluons and of $\bar{u}$,
$\bar{d}$, $u$, and $d$ quarks in a polarized proton. Parity violation searches
for physics beyond the standard model will be competitive with unpolarized
searches at the Fermilab Tevatron. Transverse spin will explore transversity
for the first time, as well as quark-gluon correlations in the proton. Spin
dependence of the total cross section and in the Coulomb nuclear interference
region will be measured at collider energies for the first time. These
qualitatively new measurements can be expected to deepen our understanding of
the structure of matter and of the strong interaction.

</DOC>
<DOC>
<DOCNO> 68923 </DOCNO>
Renormalization Group Improved Gap Equation for Color Superconductors


  The renormalization group is used to resum leading logarithmic contributions
of the form alpha_s^{n+1} beta_0^n log^n (Delta/mu) to the gap equation
appropriate for high density QCD. The scale dependence of the strong coupling
constant alpha_s increases the gap by a factor of exp(33/16 (pi^2/4 - 1)) ~ 20
in the small coupling limit.

</DOC>
<DOC>
<DOCNO> 122328 </DOCNO>
Apparent and actual galaxy cluster temperatures


  The redshift evolution of the galaxy cluster temperature function is a
powerful probe of cosmology. However, its determination requires the
measurement of redshifts for all clusters in a catalogue, which is likely to
prove challenging for large catalogues expected from XMM--Newton, which may
contain of order 2000 clusters with measurable temperatures distributed around
the sky. In this paper we study the apparent cluster temperature, which can be
obtained without cluster redshifts. We show that the apparent temperature
function itself is of limited use in constraining cosmology, and so concentrate
our focus on studying how apparent temperatures can be combined with other
X-ray information to constrain the redshift. We also briefly study the
circumstances in which non-thermal spectral features can give redshift
information.

</DOC>
<DOC>
<DOCNO> 85072 </DOCNO>
Deviations from Einstein's Gravity at Large and Short Distances


  In this talk I will describe some recent results on the sensitivity of
resonant mass detectors shaped as a hollow sphere to scalar gravitational
radiation. Detection of this type of gravitational radiation will signal
deviations from Einstein's gravity at large distances. I will then discuss a
class of experiments aiming at finding deviations from Einstein's gravity at
distances below 1 cm. I will review the main experimental difficulties in
performing such experiments and evaluate the effects to be taken in account.

</DOC>
<DOC>
<DOCNO> 101041 </DOCNO>
On the Stability of the Standard Riemann Semigroup


  We consider the dependence of the entropic solution of a hyperbolic system of
conservation laws \[ \{\{array}{c} u_t + f(u)_x = 0 u(0,\cdot) = u_0 \{array}
\] on the flux function f. We prove that the solution in Lipschitz continuous
w.r.t.~the $C^0$ norm of the derivative of the perturbation of f. We apply this
result to prove the convergence of the solution of the relativistic Euler
equation to the classical limit.

</DOC>
<DOC>
<DOCNO> 101070 </DOCNO>
Some details of proofs of theorems related to the quantum dynamical


  This paper gives some further details of proofs of some theorems related to
the quantum dynamical Yang-Baxter equation. This mainly expands proofs given in
"Lectures on the dynamical Yang-Baxter equation" by P. Etingof and O.
Schiffmann, math.QA/9908064. This concerns the intertwining operator, the
fusion matrix, the exchange matrix and the difference operators. The last part
expands proofs given in "Traces of intertwiners for quantum groups and
difference equations, I" by P. Etingof and A. Varchenko, math.QA/9907181. This
concerns the dual Macdonald-Ruijsenaars equations. This paper does not claim
originality, priority or completeness. It is meant as a service to whoever may
take profit of it.

</DOC>
<DOC>
<DOCNO> 102745 </DOCNO>
Representations of the Exceptional Lie superalgebra $E(3,6): II. Four


  Four $\ZZ_+$-bigraded complexes with the action of the exceptional
infinite-dimensional Lie superalgebra E(3,6) are constructed. We show that all
the images and cokernels and all but three kernels of the differentials are
irreducible E(3,6)-modules. This is based on the list of singular vectors and
the calculation of homology of these complexes. As a result, we obtain an
explicit construction of all degenerate irreducible E(3,6)-modules and compute
their characters and sizes. Since the group of symmetries of the Standard Model
$SU(3) \times SU(2) \times U(1)$ (divided by a central subgroup of order six)
is a maximal compact subgroup of the group of automorphisms of E(3,6), our
results may have applications to particle physics.

</DOC>
<DOC>
<DOCNO> 14050 </DOCNO>
Magnetization Plateaus in the Shastry-Sutherland Model for


  Magnetization plateaus in the Shastry-Sutherland model for ${\rm
SrCu_2(BO_3)_2}$ are studied by the perturbation expansion method. The
fourth-order effective Hamiltonian which describes the dynamics of triplet
dimers (TD's) with $S^{\rm tot}_z=1$ in the singlet sea is derived and then
partially diagonalized for the space that consists of the TD configurations
with the lowest second-order energy. The fourth-order terms are treated within
a low-density approximation. Our procedure makes clear how TD interactions are
responsible for the formation of magnetization plateaus. Particularly, the
1/4-plateau is obtained by the fourth-neighbor TD repulsion in the fourth-order
perturbation, and a diagonal stripe arrangement of TD's appears at this
plateau.

</DOC>
<DOC>
<DOCNO> 71076 </DOCNO>
Instantaneous Bethe-Salpeter Equation: (Semi-)Analytical Solution


  The Bethe-Salpeter equation for bound states of a fermion-antifermion pair in
the instantaneous approximation for the involved interaction kernel is
converted into an equivalent matrix eigenvalue problem with explicitly
(algebraically) given matrices.

</DOC>
<DOC>
<DOCNO> 121519 </DOCNO>
Neon abundances in normal late-B and mercury-manganese stars


  We make new Non-LTE calculations to deduce abundances of neon from
visible-region echelle spectra of selected Ne I lines in 7 normal stars and 20
HgMn stars. We find that the best strong blend-free Ne line which can be used
at the lower end of the Teff range is 6402 A, although several other
potentially useful Ne I lines are found in the red region of the spectra of
these stars. The mean neon abundance in the normal stars (log A =8.10) is in
excellent agreement with the standard abundance of neon (8.08). However, in
HgMn stars, neon is almost universally underabundant, ranging from marginal
deficits of 0.1-0.3 dex to underabundances of an order of magnitude or more. In
many cases, the lines are so weak that only upper limits can be established.
The most extreme example found is upsilon Her with an underabundance of at
least 1.5 dex. These underabundances are qualitatively expected from radiative
acceleration calculations, which show that Ne has a very small radiative
acceleration in the photosphere and is expected to undergo gravitational
settling if mixing processes are sufficiently weak, and there is no strong
stellar wind. According to the theoretical predictions of Landstreet et al.
(1998), the low Ne abundances place an important constraint on the intensity of
such stellar winds, which must be less than $10^-14 M_sun per yr if they are
non-turbulent.

</DOC>
<DOC>
<DOCNO> 121312 </DOCNO>
SAURON Observations of Disks in Early-Type Galaxies


  We briefly describe the SAURON project, aimed at determining the intrinsic
shape and internal dynamics of spheroids. We focus here on the ability of
SAURON to identify gaseous and stellar disks and to measure their morphology
and kinematics. We illustrate some of our results with complete maps of
NGC3377, NGC3623, and NGC4365.

</DOC>
<DOC>
<DOCNO> 72292 </DOCNO>
On the Energy Loss of High Energy Quarks in a Finite-Size Quark-Gluon


  We study within the light-cone path integral approach the induced gluon
emission from a fast quark passing through a finite-size QCD plasma. We show
that the leading log approximation used in previous studies fails when the
gluon formation length becomes of the order of the length of the medium
traversed by the quark. Calculation of the energy loss beyond the leading log
approximation gives the energy loss which grows logarithmically with quark
energy contrary to the energy independent prediction of the leading log
approximation.

</DOC>
<DOC>
<DOCNO> 151346 </DOCNO>
Quantum Field Theories With Compact Noncommutative Extra Dimensions


  We study field theories on spaces with additional compact noncommutative
dimensions. As an example, we study \phi^3 on R^{1,3}\times T^{2}_\theta using
perturbation theory. The infrared divergences in the noncompact theory give
rise to unusual dynamics for the mode of \phi which is constant along the
torus. Correlation functions involving this mode vanish. Moreover, we show that
the spectrum of Kaluza-Klein excitations can be very different from the
analogous commuting theory. There is an additional contribution to the
Kaluza-Klein mass formula that resembles the contribution of winding states in
string theory. We also consider the effect of noncommutativity on the four
dimensional Kaluza-Klein excitations of a six dimensional gauge field.

</DOC>
<DOC>
<DOCNO> 178696 </DOCNO>
Anharmonic double-phonon excitations in the interacting boson model


  Double-$\gamma$ vibrations in deformed nuclei are analyzed in the context of
the interacting boson model. A simple extension of the original version of the
model towards higher-order interactions is required to explain the observed
anharmonicities of nuclear vibrations. The influence of three- and four-body
interactions on the moments of inertia of ground- and $\gamma$-bands, and on
the relative position of single-$\gamma$ and double-$\gamma$ bands is studied
in detail. As an example of a realistic calculation, spectra and transitions of
the highly $\gamma$-anharmonic nuclei $^{164}$Dy, $^{166}$Er, and $^{168}$Er
are interpreted in this approach.

</DOC>
<DOC>
<DOCNO> 102007 </DOCNO>
$L^p-$maximal regularity on Banach spaces with a Schauder basis


  We investigate the problem of $L^p$-maximal regularity on Banach spaces
having a Schauder basis. Our results improve those of a recent paper.

</DOC>
<DOC>
<DOCNO> 169977 </DOCNO>
Efficient State Preparation via Ion Trap Quantum Computing and Quantum


  We present a scheme to prepare a quantum state in a ion trap with probability
approaching to one by means of ion trap quantum computing and Grover's quantum
search algorithm acting on trapped ions.

</DOC>
<DOC>
<DOCNO> 68775 </DOCNO>
Strongly-Interacting Heavy Flavors Beyond the Standard Model


  The origin of mass must lie in physics beyond the Standard Model. Dynamical
electroweak symmetry breaking models like technicolor can generate masses for
the W and Z bosons. Providing the large top quark mass and large top-bottom
mass splitting while keeping rho parameter and flavor-changing neutral currents
small requires new strong dynamics for the top and bottom quarks. In
consequence, new particles are predicted at scales up to 10 TeV with signatures
in jets or heavy flavors. Searches for these states are underway at Fermilab
and LEP II.

</DOC>
<DOC>
<DOCNO> 70390 </DOCNO>
Precision Higgs physics at a $\gamma \gamma$ collider


  The loop induced coupling of an intermediate mass Higgs boson to two photons
is a sensitive and unique measure for precision tests of physics beyond the
Standard Model. In this work we summarize recent results on the expected
precision of the partial $\Gamma (H \to \gamma \gamma)$ width at the $\gamma
\gamma$ option of a future linear collider. Heavy particles do not decouple in
general and differences between the SM and MSSM predictions or 2HD-models can
differ in the percentile regime. Large non-Sudakov DL corrections need to be
resummed and consistency requirements demand the use of the Sterman-Weinberg
jet definition in order to avoid additional DL terms from three jet final
states. We find that the well understood background process $\gamma \gamma \to
q \bar{q}$ allows for a ${\mathcal O}$(2%) determination of $\Gamma (H \to
\gamma \gamma)$ using conservative collider parameters. Recent improvements in
the expected $\gamma \gamma$ luminosity suggest that the precision for the
diphoton partial Higgs width can be further improved and is dominated by the
error in BR($H \to b \bar{b}$) from the $e^\pm$ mode, which is presently
estimated to be in the one percent regime.

</DOC>
<DOC>
<DOCNO> 80630 </DOCNO>
A non-perturbative Lorentzian path integral for gravity


  A well-defined regularized path integral for Lorentzian quantum gravity in
three and four dimensions is constructed, given in terms of a sum over
dynamically triangulated causal space-times. Each Lorentzian geometry and its
associated action have a unique Wick rotation to the Euclidean sector. All
space-time histories possess a distinguished notion of a discrete proper time.
For finite lattice volume, the associated transfer matrix is self-adjoint and
bounded. The reflection positivity of the model ensures the existence of a
well-defined Hamiltonian. The degenerate geometric phases found previously in
dynamically triangulated Euclidean gravity are not present. The phase structure
of the new Lorentzian quantum gravity model can be readily investigated by both
analytic and numerical methods.

</DOC>
<DOC>
<DOCNO> 12933 </DOCNO>
Comment on "Strongly interacting one-dimensional Bose-Einstein


  A recent paper of Tanatar and Erkan [Phys. Rev. A 62, 053601 (2000)]
discusses a density functional approach to the impenetrable point Bose gas in
one dimension and an equation for the order parameter of the system, due
originally to Kolomeisky et al. [Phys. Rev. Lett. 85, 1146 (2000)], is derived.
We comment on the regime of validity of such a model and on qualitative
differences between predictions of the density functional approach and known
exact results.

</DOC>
<DOC>
<DOCNO> 12704 </DOCNO>
How Bob Laughlin Tamed the Giant Graviton from Taub-NUT space


  In this paper we show how two dimensional electron systems can be modeled by
strings interacting with D-branes. The dualities of string theory allow several
descriptions of the system. These include descriptions in terms of solitons in
the near horizon D6-brane theory, non-commutative gauge theory on a D2-brane,
the Matrix Theory of D0-branes and finally as a giant graviton in M-theory. The
soliton can be described as a D2-brane with an incompressible fluid of
D0-branes and charged string-ends moving on it. Including an NS5 brane in the
system allows for the existence of an edge with the characteristic massless
chiral edge states of the Quantum Hall system.

</DOC>
<DOC>
<DOCNO> 68473 </DOCNO>
Systematics of q anti-q states in the (n,M^2) and (J,M^2) planes


  In the mass region up to M < 2400 MeV we systematise mesons on the plots
(n,M^2) and (J,M^2), thus setting their classification in terms of n^{2S+1}L_J
q anti-q states. The trajectories on the (n,M^2)-plots are drawn for the
following (IJ^{PC})-states: a_0(10^{++}), a_1(11^{++}), a_2(12^{++}),
a_3(13^{++}), a_4(14^{++}), pi(10^{-+}), pi_2(12^{-+}), eta(00^{-+}),
eta_2(02^{-+})$, rho(11^{--}), f_0(00^{++}), f_2(02^{++}). All trajectories are
linear, with nearly the same slopes. At the (J,M^2)-plot we set out meson
states for leading and daughter trajectories: for pi, rho, a_1, a_2 and P'.

</DOC>
<DOC>
<DOCNO> 14019 </DOCNO>
Fractional Electrons in Liquid Helium?


  We argue that electrons in liquid helium bubbles are not fractional, they are
entangled.

</DOC>
<DOC>
<DOCNO> 119478 </DOCNO>
A Determination of the Hubble Constant from Cepheid Distances and a


  We present a measurement of the Hubble Constant based on Cepheid distances to
27 galaxies within 20 Mpc. We take the Cepheid data from published measurements
by the Hubble Telescope Key Project on the Distance Scale (H0KP). We calibrate
the Cepheid Period-Luminosity (PL) relation with data from over 700 Cepheids in
the LMC obtained by the OGLE collaboration; we assume an LMC distance modulus
of 18.50 mag (d=50.1 kpc). Using this PL calibration we obtain new distances to
the H0KP galaxies. We correct the redshifts of these galaxies for peculiar
velocities using two distinct velocity field models: the phenomenological model
of Tonry et al. and a model based on the IRAS density field and linear
gravitational instability theory. We combine the Cepheid distances with the
corrected redshifts for the 27 galaxies to derive H_0, the Hubble constant. The
results are H_0 = 85 +/- 5 km/s/Mpc (random error) at 95% confidence when the
IRAS model is used, and 92 +/- 5 km/s/Mpc when the phenomenological model is
used. The IRAS model is a better fit to the data and the Hubble constant it
returns is more reliable. Systematic error stems mainly from LMC distance
uncertainty which is not directly addressed by this paper. Our value of H_0 is
significantly larger than that quoted by the H0KP, H_0 = 71 +/- 6 km/s/Mpc.
Cepheid recalibration explains ~30% of this difference, velocity field analysis
accounts for ~70%. We discuss in detail possible reasons for this discrepancy
and future study needed to resolve it.

</DOC>
<DOC>
<DOCNO> 121952 </DOCNO>
Gaussianity of Cosmic Velocity Fields and Linearity of the


  We present an extensive numerical study of the relation between the cosmic
peculiar velocity field and the gravitational acceleration field. We show that
on mildly non-linear scales (3-10 Mpc Gaussian smoothing), the distribution of
the Cartesian coordinates of each of these fields is very well approximated by
a Gaussian. In particular, their negentropies and kurtoses are small compared
to those of the velocity divergence and density fields. We find that at these
scales the relation between the velocity and acceleration fields follows linear
theory to high accuracy. The non-linear correction of Kudlicki et al (2000a,b)
works still better: its reconstruction errors are several times smaller than
those of the linear theory approximation.

</DOC>
<DOC>
<DOCNO> 70637 </DOCNO>
Many-Body Approach to Mesons, Hybrids and Glueballs


  We represent QCD at the hadronic scale by means of an effective Hamiltonian,
H, formulated in the Coulomb gauge. As in the Nambu-Jona-Lasinio model, chiral
symmetry is dynamically broken, however our approach is renormalizable and also
includes confinement through a linear potential with slope specified by lattice
gauge theory. We perform a comparative study of alternative many-body
techniques for approximately diagonalizing H: BCS for the vacuum ground state;
TDA and RPA for the excited hadron states. We adequately describe the
experimental meson and lattice glueball spectra and perform the first
relativistic, three quasiparticle calculation for hybrid mesons. In general
agreement with alternative theoretical approaches, we predict the lightest
hybrid states near but above 2 GeV, indicating the two recently observed
$J^{PC} = 1^{-+}$ exotics at 1.4 and 1.6 GeV are of a different, perhaps four
quark, structure. We also detail a new isospin dependent interaction from
$q\bar{q}$ color octet annihilation (analogous to ortho positronium) which
splits I = 0 and I = 1 states.

</DOC>
<DOC>
<DOCNO> 8880 </DOCNO>
Turbo codes: the phase transition


  Turbo codes are a very efficient method for communicating reliably through a
noisy channel. There is no theoretical understanding of their effectiveness. In
[1] they are mapped onto a class of disordered spin models. The analytical
calculations concerning these models are reported here. We prove the existence
of a no-error phase and compute its local stability threshold. As a byproduct,
we gain some insight into the dynamics of the decoding algorithm.

</DOC>
<DOC>
<DOCNO> 99418 </DOCNO>
Twist deformations for generalized Heisenberg algebras


  Multidimensional Heisenberg algebras, whose creation and annihilation
operators are the N-dimensional vectors, can be injected into simple Lie
algebras g. It is demonstrated that the spectrum of their deformations can be
investigated using chains of extended Jordanian twists applied to U(g). In the
case of U(sl(N)) (for N>5) the two-dimensional Heisenberg subalgebras have nine
deformed costructures connected by four "internal" and "external" twists
composing the commutative diagram.

</DOC>
<DOC>
<DOCNO> 120353 </DOCNO>
X-Ray Bursts and Proton Captures Close to the Dripline


  The hydrogen-rich accreted envelopes of neutron stars in binary systems are
the site for the rapid proton capture nucleosynthethic process (rp-process),
which involves nuclei close to the proton dripline. An overview of the relevant
reactions and nuclear properties for rp-process studies is given, along with
motivations for further experimental nuclear physics studies.

</DOC>
<DOC>
<DOCNO> 70468 </DOCNO>
A chiral crystal in cold QCD matter at intermediate densities?


  The analogue of Overhauser (particle-hole) pairing in electronic systems
(spin-density waves with non-zero total momentum $Q$) is analyzed in
finite-density QCD for 3 colors and 2 flavors, and compared to the
color-superconducting BCS ground state (particle-particle pairing, $Q$=0). The
calculations are based on effective nonperturbative four-fermion interactions
acting in both the scalar diquark as well as the scalar-isoscalar quark-hole
('$\sigma$') channel. Within the Nambu-Gorkov formalism we set up the coupled
channel problem including multiple chiral density wave formation, and evaluate
the resulting gaps and free energies. Employing medium-modified
instanton-induced 't Hooft interactions, as applicable around $\mu_q\simeq 0.4$
GeV (or 4 times nuclear saturation density), we find the 'chiral crystal phase'
to be competitive with the color superconductor.

</DOC>
<DOC>
<DOCNO> 8233 </DOCNO>
Quenched noise and over-active sites in sandpile dynamics


  The dynamics of sandpile models are mapped to discrete interface equations.
We study in detail the Bak-Tang-Wiesenfeld model, a stochastic model with
random thresholds, and the Manna model. These are, respectively,
discretizations of the quenched Edwards-Wilkinson equation with columnar,
point-like and correlated noise, with the constraint that the interface
velocity is either zero or exactly one. The constraint, embedded in the
sandpile rules, gives rise to another noise component. This term has for the
Bak-Tang-Wiesenfeld model long-range on-site correlations and reveals that with
open boundary conditions there is no spatial translational invariance.

</DOC>
<DOC>
<DOCNO> 123269 </DOCNO>
Intrinsic intraday variability in the gravitational lens system


  Radio monitoring of the gravitational lens system B0218+357 reveals it to be
a highly variable source with variations on timescales of a few days correlated
in both images. This shows that the variability is intrinsic to the background
lensed source and suggests that similar variations in other intraday variable
sources can also be intrinsic in origin.

</DOC>
<DOC>
<DOCNO> 120967 </DOCNO>
Photometric Properties of the Arp 220 Super Star Clusters


  We investigate the photometric properties of six super stellar clusters
(SSCs) seen in both the optical and near-infrared Hubble Space Telescope images
of the local ultraluminous starburst galaxy Arp 220. Three of the SSCs are
located in the central 0.5 kpc region. The remaining three are in the
circumnuclear region between 0.5 kpc and 2.5 kpc from the centre. Comparing the
observed spectral energy distributions (SEDs) of the SSCs with the Starburst99
models of Leitherer et al., we confirm that all the three nuclear SSCs are
heavily obscured ($A_V \sim 10$ mag). Considering the results from this
comparison in conjunction with measurements of the near-infrared CO absorption
index and of millimetre CO line widths and luminosities, we estimate the ages
of the nuclear SSCs to be $10^7 - 10^8$ yrs. The bolometric luminosity of the
three nuclear SSCs is at most one-fifth of the total bolometric luminosity of
Arp 220. On the other hand, the circumnuclear SSCs have little internal
extinction ($A_V \leq$ 1 mag). These contribute negligibly to the total
bolometric luminosity.

</DOC>
<DOC>
<DOCNO> 84149 </DOCNO>
Integration of the GHP equations in spacetimes admitting a geodesic


  We perform a complete rho-integration of the GHP equations for all spacetimes
that admit a geodesic shear-free expanding null congruence, whose Ricci spinor
is aligned to the congruence and whose Ricci scalar is constant. We also deduce
the system of GHP equations after the integration is completed, and discuss a
few applications.

</DOC>
<DOC>
<DOCNO> 119019 </DOCNO>
Microlensing and Galactic Structure


  Because we know little about the Galactic force-field away from the plane,
the Galactic mass distribution is very ill-determined. I show that a
microlensing survey of galaxies closer than 50 Mpc would enable us to map in
three dimensions the Galactic density of stellar mass, which should be strictly
less than the total mass density. A lower limit can be placed on the stellar
mass needed at R<R_0 to generate the measured optical depth towards sources in
the bulge. If the Galaxy is barred, this limit is lower by a factor of up to
two than in the axisymmetric case. Even our limited knowledge of the Galactic
force field suffices to rule out the presence of the amount of mass an
axisymmetric Galaxy needs to generate the measured optical depth. Several lines
of argument imply that the Galaxy is strongly barred only at R < 4 kpc, and if
this is the case, even barred Galaxy models cannot generate the measured
optical depth without violating some constraint on the Galactic force-field.
Galactic mass models that are based on the assumption that light traces mass,
for which there is significant support in the inner Galaxy, yield microlensing
optical depths that are smaller than the measured value by a factor of more
than 2.5.

</DOC>
<DOC>
<DOCNO> 69278 </DOCNO>
Self-organized criticality in atmospheric cascades


  We argue that atmospheric cascades can be regarded as example of the
self-organized criticality and studied by using Levy flights and nonextensive
approach. It allows us to understand the scale-invariant energy fluctuations
inside cascades in a natural way.

</DOC>
<DOC>
<DOCNO> 174435 </DOCNO>
Mechanisms for Direct Breakup Reactions


  We review some simple mechanisms of breakup in nuclear reactions. We mention
the spectator breakup, which is described in the post-form DWBA. The relation
to other formulations is also indicated. An especially important mechanism is
Coulomb dissociation. It is a distinct advantage that the perturbation due to
the electric field of the nucleus is exactly known. Therefore firm conclusions
can be drawn from such measurements. Some new applications of Coulomb
dissociation for nuclear astrophysics are discussed.

</DOC>
<DOC>
<DOCNO> 121716 </DOCNO>
The Assembly and Evolution of Spiral Disks


  We explore how the growth rate of spiral disks can be measured via analyses
of the scatter in the Tully-Fisher (TF) relation of local and intermediate
redshift galaxies. As an initial step, we show it is possible to construct a
low-dispersion TF relation for nearly face-on, nearby spirals. We find these
spiral disks are non-circular, (a mean ellipticity of 6%), which accounts for
about 0.1 mag of the intrinsic scatter in the nearby TF relation of even the
most ``normal'' looking spirals. If this ellipticity is induced by matter
accretion, we expect to find greater disk ellipticity or disturbance in the
past. We find evidence that more extreme outliers of the intermediate-redshift
TF relation are more morphologically and kinematically disturbed. Whether this
effect reflects a redshift trend or selection bias of local samples needs to be
addressed.

</DOC>
<DOC>
<DOCNO> 120633 </DOCNO>
The Cosmic Microwave Background for a Nearly Flat Compact Hyperbolic


  The fluctuations of the cosmic microwave background (CMB) are investigated
for a hyperbolic universe with finite volume. Four-component models with
radiation, matter, vacuum energy, and an extra spatially constant dark energy
X-component are considered. The general solution of the Friedmann equation for
the cosmic scale factor a(eta) is given for the four-component models in terms
of the Weierstrass P-function. The lower part of the angular power spectra C_l
of the CMB anisotropy is computed for nearly flat models with Omega_tot <=
0.95. It is shown that the particular compact fundamental cell, which is
considered in this paper, leads to a suppression in C_l for l<10 and Omega_tot
<= 0.9.

</DOC>
<DOC>
<DOCNO> 10327 </DOCNO>
Electron Transport in Hybrid Ferromagnetic/Superconducting


  We observe large amplitude changes in the resistance of ferromagnetic (F)
wires at the onset of superconductivity of adjacent superconductors (S). New
sharp peaks of large amplitude are found in the magnetoresistance of the
F-wires. We discuss a new mechanism for the long-range superconducting
proximity effect in F/S nanostructures based on the analysis of the topologies
of actual Fermi-surfaces in ferromagnetic metals.

</DOC>
<DOC>
<DOCNO> 123220 </DOCNO>
High velocity structures in, and the X-ray emission from the LBV nebula


  The Luminous Blue Variable star Eta Carinae is one of the most massive stars
known. It underwent a giant eruption in 1843 in which the Homunculus nebula was
created. ROSAT and ASCA data indicate the existence of a hard and a soft X-ray
component which appear to be spatially distinct: a softer diffuse shell of the
nebula around Eta Carinae and a harder point-like source centered on the star
Eta Car. Astonishingly the morphology of the X-ray emission is very different
from the optical appearance of the nebula. We present a comparative analysis of
optical morphology, the kinematics, and the diffuse soft X-ray structure of the
nebula around Eta Carinae. Our kinematic analysis of the nebula shows extremely
high expansion velocities. We find a strong correlation between the X-ray
emission and the knots in the nebula and the largest velocities, i.e. the X-ray
morphology of the nebula around Eta Carinae is determined by the interaction
between material streaming away from Eta Car and the ambient medium.

</DOC>
<DOC>
<DOCNO> 68590 </DOCNO>
Radiative Higgs-Sector CP Violation in the MSSM


  We briefly review the phenomenological implications of the minimal
supersymmetric standard model (MSSM) with explicit radiative breaking of CP
invariance in the Higgs sector for the LEP2 and Tevatron colliders.

</DOC>
<DOC>
<DOCNO> 72191 </DOCNO>
Pseudo-Dirac Scenario for Neutrino Oscillations


  We argue how pseudo-Dirac scenario for neutrinos leads to rich neutrino
oscillation phenomena, including oscillation inside each generation. The
pseudo-Dirac scenario is generalized by incorporating generation mixings and
formulae for the various neutrino oscillations are derived. As the application
we compare the formulae with the corresponding data. We find that observed
pattern of mixings, such as almost maximal mixing in the atmospheric neutrino
oscillation, is naturally explained in the generalized Pseudo-Dirac scenario
with small generation mixings. We, however, also point out that there remain
some problems to be settled for this scenario to be viable. The possible
theoretical framework to realize the pseudo-Dirac scenario is also briefly
commented on.

</DOC>
<DOC>
<DOCNO> 150898 </DOCNO>
A two-dimensional integrable axionic sigma-model and T-duality


  An $S$-matrix is proposed for the two dimensional O(3) $\sigma$-model with a
dynamical $\theta$-term (axion model). Exploiting an Abelian T-duality
transformation connecting the axion model to an integrable SU(2)$\times$U(1)
symmetric principal $\sigma$-model, strong evidence is presented for the
correctness of the proposed $S$-matrix by comparing the perturbatively
calculated free energies with the ones based on the Thermodynamical Bethe
Ansatz. This T-duality transformation also leads to a new Lax-pair for both
models. The quantum non-integrability of the O(3) $\sigma$-model with a {\sl
constant} $\theta$-term, in contradistinction to the axion model, is
illustrated by calculating the $2\to3$ particle production amplitude to lowest
order in $\theta$.

</DOC>
<DOC>
<DOCNO> 71721 </DOCNO>
Chiral dynamics in the presence of bound states: kaon-nucleon


  We study the S-wave kaon-nucleon interactions for strangeness S=-1 in a novel
relativistic chiral unitary approach based on coupled channels. Dispersion
relations are used to perform the necessary resummation of the lowest order
relativistic chiral Lagrangian. A good description of the data in the K^- p,
\pi \Sigma and \pi \Lambda channels is obtained. We show how this method can be
systematically extended to higher orders, emphasizing its applicability to any
scenario of strong self-interactions where the perturbative series diverges
even at low energies. Discussions about the differences to existing approaches
employing pseudo-potentials in a regulated Lippmann-Schwinger equation are
included. Finally, we describe the resonance content of our meson-baryon
amplitudes and discuss its nature.

</DOC>
<DOC>
<DOCNO> 39975 </DOCNO>
The QCD and Standard Model Working Group: Summary Report from Les


  The Les Houches Workshop on Physics at TeV Colliders took place from June
8-18, 1999. One of the three working groups at Les Houches concentrated on QCD
issues, both at the Tevatron Collider and at the LHC. Besides the interest in
QCD in its own right, QCD dynamics plays an important role in the production
mechanisms for any new physics process that might be observed at either
collider, as well as any processes that may form backgrounds to the new
physics. This writeup serves both as a pedagogical overview of QCD as well as
an update on the current status of the field.

</DOC>
<DOC>
<DOCNO> 117220 </DOCNO>
Spherical harmonic decomposition applied to spatial-temporal analysis of


  We demonstrate an application of spherical harmonic decomposition to analysis
of the human electroencephalogram (EEG). We implement two methods and discuss
issues specific to analysis of hemispherical, irregularly sampled data.
Performance of the methods and spatial sampling requirements are quantified
using simulated data. The analysis is applied to experimental EEG data,
confirming earlier reports of an approximate frequency-wavenumber relationship
in some bands.

</DOC>
<DOC>
<DOCNO> 178756 </DOCNO>
Perspectives of $e^+e^-$ production in pp, pd and p Be reactions at SIS


  We study dilepton production from pp, pd and p Be collisions from 1 - 5 GeV
including the $\pi^0$, $\eta$, $\omega$ and $\Delta$ Dalitz decays, direct
decays of vector mesons ($\rho$, $\omega$) as well as subthreshold $\rho$
production via baryonic resonances (e.g. $D_{13}(1520), P_{11}(1710)$). Our
calculations compare rather well with the pp and pd data from the DLS
Collaboration, however, overestimate slightly the 'old' p Be data from that
group. Futhermore, detailed predictions for differential dilepton spectra at
SIS energies are made with a high mass resolution that can be controlled
experimentally by the HADES Collaboration in near future.

</DOC>
<DOC>
<DOCNO> 85199 </DOCNO>
Constructing stellar objects with multiple necks


  We discuss the construction of perfect fluid stellar objects having optical
geometries with multiple necks corresponding to spatially closed unstable
lightlike geodesics. We prove that there exist physically reasonable models
with arbitrarily many necks. We also show how a first order phase transition
can give rise to quite pronounced secondary double necks. The analysis is
carried out using a modification of a recent dynamical systems formulation of
the TOV equations due to Nilsson and Uggla. Our reformulation allows for a very
general family of equations of state including, for example, phase transitions.

</DOC>
<DOC>
<DOCNO> 8565 </DOCNO>
Stripe Dynamics, Global Phase Ordering and Quantum Criticality in High


  By modeling the stripe phase in cuprates as spin gapped stripes coupled to
the RVB liquid of preformed electron pairs, I derive the low energy effective
theory of the RVB phase variable. It is found that the effect of stripe
dynamics (including both longitudinal and transverse modes) leads to incipient
temporal phase stiffness in the RVB liquid, which tunes a quantum phase
transition toward a superconducting ground state with global phase order.
Physical consequences of this quantum criticality are discussed.

</DOC>
<DOC>
<DOCNO> 99943 </DOCNO>
Similarity and Consimilarity of Elements in Real Cayley-Dickson Algebras


  A set of valuable universal similarity factorization equalities is
established over complex Clifford algebras $\Cn.$ Through them matrix
representations of complex Clifford algebras $\Cn$ can directly be derived, and
their properties can easily be determined.

</DOC>
<DOC>
<DOCNO> 40248 </DOCNO>
Resonant Formation of $d\mu t$ Molecules in Deuterium: An Atomic Beam


  Resonant formation of $d\mu t$ molecules in collisions of muonic tritium
($\mu t$) on D$_2$ was investigated using a beam of $\mu t$ atoms,
demonstrating a new direct approach in muon catalyzed fusion studies. Strong
epithermal resonances in $d\mu t$ formation were directly revealed for the
first time. From the time-of-flight analysis of $2036\pm 116$ $dt$ fusion
events, a formation rate consistent with $0.73\pm (0.16)_{meas} \pm
(0.09)_{model}$ times the theoretical prediction was obtained. For the largest
peak at a resonance energy of $0.423 \pm 0.037$ eV, this corresponds to a rate
of $(7.1 \pm 1.8) \times 10^9$ s$^{-1}$, more than an order of magnitude larger
than those at low energies.

</DOC>
<DOC>
<DOCNO> 117703 </DOCNO>
On the Origin of Quasi-Periodic Oscillations and Broad-band Noise in


  Accreting neutron stars and black holes share a number of rapid variability
characteristics, such as quasi-periodic oscillations and broad-band noise. The
frequencies of these features were recently shown to be comparable to
fundamental general relativistic frequencies of perturbed test-particle orbits
near the compact objects. In this paper we propose a dynamical model for
producing modulations in the inner disk properties at these characteristic
frequencies. We postulate that a transition radius exists in the accretion disk
close to the compact object and investigate its response to a broad spectrum of
density fluctuations. We find that the transition radius acts as a low
band-pass filter with a broadband response that is constant at frequencies
lower than the inverse radial drift timescale and decreases above it as the
inverse of the frequency. Moreover, the response shows strong resonances at
frequencies nearly equal to the orbital, periastron-precession, and
nodal-precession frequencies, thereby accounting for the observed power-density
spectra of accreting compact objects and the correlations between their
characteristic frequencies.

</DOC>
<DOC>
<DOCNO> 170492 </DOCNO>
Nonadditivity of Bipartite Distillable Entanglement follows from


  Assuming the validity of a conjecture in quant-ph/9910026 and
quant-ph/9910022 we show that the distillable entanglement for two bipartite
states, each of which individually has zero distillable entanglement, can be
nonzero. We show that this also implies that the distillable entanglement is
not a convex function. Our example consists of the tensor product of a bound
entangled state based on an unextendible product basis with a Werner state
which lies in the class of conjectured undistillable states.

</DOC>
<DOC>
<DOCNO> 13619 </DOCNO>
Phase separation in an homogeneous shear flow: Morphology, growth laws


  We investigate numerically the influence of an homogeneous shear flow on the
spinodal decomposition of a binary mixture by solving the Cahn-Hilliard
equation in a two-dimensional geometry. Several aspects of this much studied
problem are clarified. Our numerical data show unambiguously that, in the shear
flow, the domains have on average an elliptic shape. The time evolution of the
three parameters describing this ellipse are obtained for a wide range of shear
rates. For the lowest shear rates investigated, we find the growth laws for the
two principal axis $R_\perp (t) \sim constant$, $R_\parallel(t) \sim t$, while
the mean orientation of the domains with respect to the flow is inversely
proportional to the strain. This implies that when hydrodynamics is neglected a
shear flow does not stop the domain growth process. We investigate also the
possibility of dynamic scaling, and show that only a non trivial form of
scaling holds, as predicted by a recent analytical approach to the case of a
non-conserved order parameter. We show that a simple physical argument may
account for these results.

</DOC>
<DOC>
<DOCNO> 170130 </DOCNO>
Proposal for preparing delocalised mesoscopic states of material


  A scheme is proposed for preparing delocalised mesoscopic states of the
motion of two or more atoms trapped at distantly-separated locations.
Generation of entanglement is achieved using interactions in cavity quantum
electrodynamics which facilitate motional quantum state transmission, via
light, between separate nodes of a quantum network. Possible applications of
the scheme are discussed.

</DOC>
<DOC>
<DOCNO> 152617 </DOCNO>
How Noncommutative Gauge Theories Couple to Gravity


  We study coupling of noncommutative gauge theories on branes to closed string
in the bulk. We derive an expression for the gauge theory operator dual to the
bulk graviton, both in bosonic string theory and superstring theory. In either
case, we find that the coupling is different from what was expected in the
literature when the graviton is polarized in the noncommutative directions. In
the case of superstring, the expression for the energy-momentum tensor is
consistent with the way the bulk metric appears in the action for the
noncommutative gauge theory. We also clarify some aspects of the correspondence
between operators in the gauge theory and boundary conditions in the dual
gravitational description.

</DOC>
<DOC>
<DOCNO> 122989 </DOCNO>
Radial gradients and metallicities in the galactic disk


  Radial O/H abundance gradients derived from HII regions, hot stars and
planetary nebulae are combined with [Fe/H] gradients from open cluster stars in
order to derive an independent [O/Fe] x [Fe/H] relation for the galactic disk.
A comparison of the obtained relation with recent observational data and
theoretical models suggests that the [O/Fe] ratio is not higher than [O/Fe] ~
0.4, at least within the metallicity range of the considered samples.

</DOC>
<DOC>
<DOCNO> 80715 </DOCNO>
Gauge Field Theory Coherent States (GCS) : II. Peakedness Properties


  In this article we apply the methods outlined in the previous paper of this
series to the particular set of states obtained by choosing the complexifier to
be a Laplace operator for each edge of a graph. The corresponding coherent
state transform was introduced by Hall for one edge and generalized by
Ashtekar, Lewandowski, Marolf, Mour\~ao and Thiemann to arbitrary, finite,
piecewise analytic graphs. However, both of these works were incomplete with
respect to the following two issues : (a) The focus was on the unitarity of the
transform and left the properties of the corresponding coherent states
themselves untouched. (b) While these states depend in some sense on
complexified connections, it remained unclear what the complexification was in
terms of the coordinates of the underlying real phase space. In this paper we
resolve these issues, in particular, we prove that this family of states
satisfies all the usual properties : i) Peakedness in the configuration,
momentum and phase space (or Bargmann-Segal) representation, ii) Saturation of
the unquenched Heisenberg uncertainty bound. iii) (Over)completeness. These
states therefore comprise a candidate family for the semi-classical analysis of
canonical quantum gravity and quantum gauge theory coupled to quantum gravity,
enable error-controlled approximations and set a new starting point for {\it
numerical canonical quantum general relativity and gauge theory}. The text is
supplemented by an appendix which contains extensive graphics in order to give
a feeling for the so far unknown peakedness properties of the states
constructed.

</DOC>
<DOC>
<DOCNO> 11251 </DOCNO>
Origin and pressure dependence of ferromagnetism in A2Mn2O7 pyrochlores


  Non-conventional mechanisms have been recently invoked in order to explain
the ferromagnetic ground state of A2Mn2O7 pyrochlores (A=Y, In, Lu and Tl) and
the puzzling decrease of their Curie temperatures with applied pressure. Here
we show, using a perturbation expansion in the Mn-O hopping term, that both
features can be understood within the superexhange model, provided that the
intra-atomic oxygen interactions are properly taken into account. An additional
coupling between the Mn ions mediated by the In(5s)/Tl(6s) bands yields the
higher Tc's of these two compounds, this mechamism enhancing their
ferromagnetism for higher pressures.

</DOC>
<DOC>
<DOCNO> 152594 </DOCNO>
Type II NS Five-Branes: Non Critical Strings and their Topological


  The near-horizon geometry of parallel NS5-branes is described by an exact
superconformal 2d field theory based on K^10 = W(k)^4 x M^6, with M^6 a flat
5+1 space time and W(k)^4 =U(1) x SU(2)(k), a four dimensional background with
non-trivial dilaton. The ten-dimensional ``BULK'' spectrum of excitations of
K^10 can be derived combining unitary representations of the N=4 superconformal
theory of W(k)^4 and M^6 in a modular-invariant way. All Bulk states are
massive and belong to the long representations of the N=2 six dimensional
space-time supersymmetry. The NS5-brane states, propagating on M^6, belong to
the short representations of N=2. Both the bulk and the brane spectrum is
derived using the powerful worldsheet technics of the N=4 superconformal
theories. We claim that both bulk and brane states are necessary to well define
the theory. The non abelian U(n) or SO(2n) structure of the 5-brane fields
follows from the fusion coefficients appearing in the correlation functions
involving SU(2)(k) conformal fields.

</DOC>
<DOC>
<DOCNO> 71182 </DOCNO>
Role of N*(1650) in the near threshold pp --> p Lambda K+ and pp --> p


  We investigate the pp --> p Lambda K+ and pp --> p Sigma0 K+ reactions at
beam energies near their thresholds within an effective Lagrangian model, where
the strangeness production proceeds via the excitation of N*(1650), N*(1710),
and N*(1720) baryonic resonances. It is found that the $N^*$(1650) resonance
dominates both these reactions at near threshold energies. The contributions
from this resonance together with the final state interaction among the
outgoing particles are able to explain the observed beam energy dependence of
the ratio of the cross sections of the two reactions in the near threshold
region.

</DOC>
<DOC>
<DOCNO> 117457 </DOCNO>
Phase lag variability associated with the 0.5-10 Hz QPO in GRS 1915+105


  We have used Rossi X-ray Timing Explorer data to measure the lags between
soft (2-5 keV) and hard (5-13 keV) photons and to study the aperiodic
variability of the superluminal black hole candidate GRS 1915+105 during
low-flux states. The power density spectra exhibit quasi-periodic oscillations
(QPO) whose frequency increases with increasing count rate and varies in the
frequency range 0.6-8 Hz. A correlation between the QPO frequency and the phase
lag spectra is reported for the first time. This correlation is found for both
the phase lag continuum and the phase lag at the QPO frequency. We find that as
the QPO frequency moves to higher values the phase lags reverse sign from
positive to negative. The absolute value of the lag always increases with
photon energy. The negative (soft) lags are associated with a softer energy
spectrum, whereas the positive (hard) lags are seen when the source is harder.
We describe a possible scenario that may account for the change in the sign of
the lags.

</DOC>
<DOC>
<DOCNO> 151254 </DOCNO>
Worldsheet and Spacetime Properties of p-p' System with B Field and


  We study worldsheet and spacetime properties of the p-p' (p < p') open string
system with constant B_{ij} field viewed from the Dp' brane. The description of
this system in terms of the CFT with spin and twist fields leads us to consider
the renormal ordering procedure from the SL(2,R) invariant vacuum to the
oscillator vacuum. We compute the attendant two distinct superspace two-point
functions as well as their difference (the subtracted two-point function).
These bring us an integral (Koba-Nielsen) representation for the multiparticle
tree scattering amplitudes consisting of N-2 vectors and two tachyons. We
evaluate them explicitly for the N=3,4 cases. Several novel features are
observed which include a momentum dependent multiplicative factor to each
external vector leg and the emergence of a symplectic tensor multiplying the
polarization vectors. In the zero slope limit, the principal parts of the
amplitudes translate into a noncommutative field theory in p'+1 dimensions in
which a scalar field decaying exponentially in (p'-p) dimensions and a
noncommutative U(1) gauge field interact via the minimal coupling and a new
interaction. A large number of nearly massless states noted before are shown to
propagate in the t-channel.

</DOC>
<DOC>
<DOCNO> 170324 </DOCNO>
Universal quantum computation with two-level trapped ions


  Although the initial proposal for ion trap quantum computation made use of an
auxiliary internal level to perform logic between ions, this resource is not
necessary in principle. Instead, one may perform such operations directly using
sideband laser pulses, operating with an arbitrary (sufficiently small)
Lamb-Dicke parameter. We explore the potential of this technique, showing how
to perform logical operations between the internal state of an ion and the
collective motional state and giving explicit constructions for a
controlled-not gate between ions.

</DOC>
<DOC>
<DOCNO> 85345 </DOCNO>
Conformal general relativity contains the quantum


  Based on the de Broglie-Bohm relativistic quantum theory of motion we show
that the conformal formulation of general relativity, being linked with a
Weyl-integrable geometry, may implicitly contain the quantum effects of matter.
In this context the Mach's principle is discussed.

</DOC>
<DOC>
<DOCNO> 118886 </DOCNO>
Structure and Star Formation in NGC 925


  We present the results from an optical study of the stellar & star formation
properties of NGC 925 using the WIYN 3.5m telescope. Images in B,V,R, & H-alpha
reveal a galaxy that is fraught with asymmetries. From isophote fits we
discover that the bar center is not coincident with the center of the outer
isophotes nor with the dynamical center (from Pisano et al. 1998). Cuts across
the spiral arms reveal that the northern arms are distinctly different from the
southern arm. The southern arm not only appears more coherent, but the peaks in
stellar and H-alpha emission are found to be coincident with those of the HI
distribution, while no such consistency is present in the northern disk. We
also examine the gas surface density criterion for massive star formation in
NGC 925, and find that its behavior is more consistent with that for irregular
galaxies, than with late-type spirals. In particular, star formation persists
beyond the radius at which the gas surface density falls below the predicted
critical value for star formation for late-type spirals. Such properties are
characteristic of Magellanic spirals, but are present at a less dramatic level
in NGC 925, a late-type spiral.

</DOC>
<DOC>
<DOCNO> 69549 </DOCNO>
Gauge-invariant description of the electromagnetic field in the Higgs


  It is shown that the definition of the photon field in the broken-symmetry
phase of the electroweak theory proposed recently by O.T(ornkvist is equivalent
to that proposed previously by Vlasov et al.

</DOC>
<DOC>
<DOCNO> 123237 </DOCNO>
A Dynamic Interstellar Medium: Recent Numerical Simulations


  Recent numerical simulations of the interstellar medium driven by energy
input from supernovae and stellar winds indicate that HI clouds can be formed
by compression in shock waves and colliding turbulent streams without any help
from thermal and gravitational instabilities. The filling factor of the hot
phase in these models does not exceed 20-40% at the midplane. The hot gas is
involved in a systematic vertical outflow at |z|<1-3 kpc, similar to that
expected for galactic fountains, whereas the warm component may remain in
hydrostatic equilibrium. The turbulent velocity is larger in the warmer phases,
being 3, 10 and 40 km/s in the cool, warm and hot phases, respectively,
according to one of the simulations. The models exhibit global variability in
the total kinetic and thermal energy and star formation rate at periods of
(0.4-4)x10^8 yr. Current models are still unable to reproduce dynamo action in
the interstellar gas; we briefly discuss implications of the dynamo theory for
turbulent interstellar magnetic fields.

</DOC>
<DOC>
<DOCNO> 84680 </DOCNO>
The newest release of the Ortocartan set of programs for algebraic


  The program Ortocartan for algebraic calculations in relativity has just been
implemented in the Codemist Standard Lisp and can now be used under the Windows
98 and Linux operating systems. The paper describes the new facilities and
subprograms that have been implemented since the previous release in 1992.
These are: the possibility to write the output as Latex input code and as
Ortocartan's input code, the calculation of the Ellis evolution equations for
the kinematic tensors of flow, the calculation of the curvature tensors from
given (torsion-free) connection coefficients in a manifold of arbitrary
dimension, the calculation of the lagrangian from a given metric by the
Landau-Lifshitz method, the calculation of the Euler-Lagrange equations from a
given lagrangian (only for sets of ordinary differential equations) and the
calculation of first integrals of sets of ordinary differential equations of
second order (the first integrals are assumed to be polynomials of second
degree in the first derivatives of the functions).

</DOC>
<DOC>
<DOCNO> 119804 </DOCNO>
Analysis of Four A-F Supergiants in M31 from Keck HIRES Spectroscopy


  The first stellar abundances in M31 are presented, based on Keck I HIRES
spectroscopy and model atmospheres analyses of three A-F supergiants, 41-2368,
41-3712, and A-207. We also present the preliminary analysis of a fourth star,
41-3654. We find that the stellar oxygen abundances are in good agreement with
those determined from nebular studies, even though the stars do {\it not} show
a clear radial gradient in oxygen. The uncertainties in the stellar abundances
are smaller than the range in the nebular results, making these stars ideal
objects for further studies of the distribution of oxygen in M31. We show that
the stars can be used to study the abundance distributions of other elements as
well, including iron-group and heavier elements.
  The A-F supergiants also provide direct information on the metallicity and
reddening of nearby Cepheid stars. We have examined the metallicity and
reddening assumptions used for Cepheids within 1' of our targets and noted the
differences from values used in the literature.

</DOC>
<DOC>
<DOCNO> 69955 </DOCNO>
Neutrino Self-Energy and Index of Refraction in Strong Magnetic Field: A


  The Ritus' $E_{p}$ eigenfunction method is extended to the case of spin-1
charged particles in a constant electromagnetic field and used to calculate the
one-loop neutrino self-energy in the presence of a strong magnetic field.From
the obtained self-energy, the neutrino dispersion relation and index of
refraction in the magnetized vacuum are determined within the field range
$m_{e}^{2}\ll eB\ll M_{W}^{2}$. The propagation of neutrinos in the magnetized
vacuum is anisotropic due to the dependence of the index of refraction on the
angle between the directions of the neutrino momentum and the external field.
Possible cosmological implications of the results are discussed.

</DOC>
<DOC>
<DOCNO> 11139 </DOCNO>
Connection between the Slave-Particles and X-Operators Path-Integral


  In the present work it is shown that the family of first-order Lagrangians
for the t-J model and the corresponding correlation generating functional
previously found can be exactly mapped into the slave-fermion decoupled
representation. Next, by means of the Faddeev-Jackiw symplectic method, a
different family of Lagrangians is constructed and it is shown how the
corresponding correlation generating functional can be mapped into the
slave-boson representation. Finally, in order to define the propagation of
fermion modes we discuss two alternative ways to treat the fermionic sector in
the path-integral formalism for the t-J model.

</DOC>
<DOC>
<DOCNO> 99423 </DOCNO>
Embedding tangles in links


  We reprove and extend a result of David Krebes (J. Knot Theory Ramif. 8
(1999), 321-352) giving an obstruction to embedding a tangle T into a link L.
Closing the tangle up in the two obvious ways gives rise to two links, the
numerator and denominator links n(T) and d(T). Applying a homological argument
to the 2-fold branched covers of these links, we show that the gcd of the
determinants of the numerator and denominator divides the determinant of L.

</DOC>
<DOC>
<DOCNO> 11445 </DOCNO>
Digitality Induced Transition in a Small Autocatalytic System


  Autocatalytic reaction system with a small number of molecules is studied
numerically by stochastic particle simulations. A novel state due to
fluctuation and discreteness in molecular numbers is found, characterized as
extinction of molecule species alternately in the autocatalytic reaction loop.
Phase transition to this state with the change of the system size and flow is
studied, while a single-molecule switch of the molecule distributions is
reported. Relevance of the results to intracellular processes are briefly
discussed.

</DOC>
<DOC>
<DOCNO> 8939 </DOCNO>
Negative length orbits in normal-superconductor billiard systems


  The Path-Length Spectra of mesoscopic systems including diffractive
scatterers and connected to superconductor is studied theoretically. We show
that the spectra differs fundamentally from that of normal systems due to the
presence of Andreev reflection. It is shown that negative path-lengths should
arise in the spectra as opposed to normal system. To highlight this effect we
carried out both quantum mechanical and semiclassical calculations for the
simplest possible diffractive scatterer. The most pronounced peaks in the
Path-Length Spectra of the reflection amplitude are identified by the routes
that the electron and/or hole travels.

</DOC>
<DOC>
<DOCNO> 69750 </DOCNO>
Light Sterile Neutrinos from Large Extra Dimensions


  An experimentally verifiable Higgs-triplet model of neutrino masses from
large extra dimensions was recently proposed. We extend it to accomodate a
light sterile neutrino which also mixes with the three active neutrinos. A
previously proposed phenomenological model of four neutrinos (\underline {the
only viable such model now left}, in view of the latest atmospheric and solar
neutrino-oscillation data) is specifically realized.

</DOC>
<DOC>
<DOCNO> 70839 </DOCNO>
Two Higgs doublet dynamics at the electroweak phase transition: a


  Using a three-dimensional (3d) effective field theory and non-perturbative
lattice simulations, we study the MSSM electroweak phase transition with two
dynamical Higgs doublets. We first carry out a general analysis of spontaneous
CP violation in 3d two Higgs doublet models, finding that this part of the
parameter space is well separated from that corresponding to the physical MSSM.
We then choose physical parameter values with explicit CP violation and a light
right-handed stop, and determine the strength of the phase transition. We find
a transition somewhat stronger than in 2-loop perturbation theory, leading to
the conclusion that from the point of view of the non-equilibrium constraint,
MSSM electroweak baryogenesis can be allowed even for a Higgs mass mH \approx
115 GeV. We also find that small values of the mass parameter mA (\lsim 120
GeV), which would relax the experimental constraint on mH, do not weaken the
transition noticeably for a light enough stop. Finally we determine the
properties of the phase boundary.

</DOC>
<DOC>
<DOCNO> 120104 </DOCNO>
Mid infrared emission of nearby Herbig Ae/Be stars


  We present mid IR spectro-photometric imaging of a sample of eight nearby ($D
\leq 240$pc) Herbig Ae/Be stars. The spectra are dominated by photospheric
emission (HR6000), featureless infrared excess emission (T~Cha), broad silicate
emission feature (HR5999) and the infrared emission bands (HD 97048, HD 97300,
TY~CrA, HD 176386). The spectrum of HD179218 shows both silicate emission and
infrared emission bands (IEB). All stars of our sample where the spectrum is
entirely dominated by IEB have an extended emission on scales of a few thousand
AU ($\sim 10''$). We verify the derived source extension found with ISOCAM by
multi--aperture photometry with ISOPHT and compare our ISOCAM spectral
photometry with ISOSWS spectra.

</DOC>
<DOC>
<DOCNO> 118163 </DOCNO>
The entropy and energy of intergalactic gas in galaxy clusters


  Studies of the X-ray surface brightness profiles of clusters, coupled with
theoretical considerations, suggest that the breaking of self-similarity in the
hot gas results from an `entropy floor', established by some heating process,
which affects the structure of the intracluster gas strongly in lower mass
systems. Fitting analytical models for the radial variation in gas density and
temperature to X-ray spectral images from the ROSAT PSPC and ASCA GIS, we
derive gas entropy profiles for 20 galaxy clusters and groups. Scaling these
profiles to coincide in the self-similar case, the lowest mass systems are
found to have higher scaled entropy profiles than more massive systems. This
appears to be due to a baseline entropy of 70-140 h50^-1/3 keV cm^2, depending
on the extent to which shocks have been suppressed in low mass systems. The
extra entropy may be present in all systems, but is detectable only in poor
clusters, compared to the entropy generated by gravitational collapse. This
excess entropy appears to be distributed uniformly with radius outside the
central cooling regions. We determine the energy associated with this entropy
floor, by studying the net reduction in binding energy of the gas in low mass
systems, and find that it corresponds to a preheating temperature of ~0.3 keV.
Since the relationship between entropy and energy injection depends upon gas
density, we can combine the excesses of 70-140 keV cm^2 and 0.3 keV to derive
the typical electron density of the gas into which the energy was injected. The
resulting value of 1-3x10^-4 h50^1/2 cm-3, implies that the heating must have
happened prior to cluster collapse but after a redshift z~7-10. The energy
requirement is well matched to the energy from supernova explosions responsible
for the metals which now pollute the intracluster gas.

</DOC>
<DOC>
<DOCNO> 101675 </DOCNO>
New time-type and space-type non-standard quantum algebras and discrete


  Starting from the classical r-matrix of the non-standard (or Jordanian)
quantum deformation of the sl(2,R) algebra, new triangular quantum deformations
for the real Lie algebras so(2,2), so(3,1) and iso(2,1) are simultaneously
constructed by using a graded contraction scheme; these are realized as
deformations of conformal algebras of (1+1)-dimensional spacetimes. Time-type
and space-type quantum algebras are considered according to the generator that
remains primitive after deformation: either the time or the space translation,
respectively. Furthermore by introducing differential-difference conformal
realizations, these families of quantum algebras are shown to be the symmetry
algebras of either a time or a space discretization of (1+1)-dimensional (wave
and Laplace) equations on uniform lattices; the relationship with the known Lie
symmetry approach to these discrete equations is established by means of twist
maps.

</DOC>
<DOC>
<DOCNO> 120594 </DOCNO>
Galaxy clustering in the Herschel deep field


  (abridged) We present a study of the angular correlation function as measured
in the William Herschel Deep Field. This field covers 50 arcmin$^2$ and with it
we are able to investigate the scaling of the angular correlation function to
$B\sim28$, $R, I\sim 26$,$K\sim20$ and $H\sim22.5$. We compare our measurements
to results obtained from the smaller Hubble Deep Field. To interpret our
results, we use a model which correctly predicts colours, number counts and
redshift distributions for the faint galaxy population. We find that at fixed
separation the amplitude of $\omega(\theta)$ measured in $BRI$ bandpasses is
lower than the predictions of a model containing with no luminosity evolution
and stable clustering growth in proper co-ordinates. However, in the
near-infrared bandpasses, our measurements are consistent with the predictions
of an essentially non-evolving $K-$ selected galaxy redshift distribution. In
the range $B\sim27-28$ we find that our correlation amplitudes are independent
of magnitude, which is consistent with the observed flattening of the number
count slope and correspondingly slower increase of the cosmological volume
element expected at these magnitudes. Our measurements in all bandpasses are
consistent with a rapid growth of galaxy clustering ($0 < \epsilon < 2 $ in the
normal parametrisation) on the sub-Mpc scales which our survey probes. We
demonstrate that this rapid growth of clustering is consistent with the
predictions of biased models of galaxy formation, which indicate that a rapid
rate of clustering growth is expected for the intrinsically faint galaxies
which dominate our survey.

</DOC>
<DOC>
<DOCNO> 150627 </DOCNO>
Supergravity Predictions on Conformal Field Theories


  We give an update on recent results about the matching between CFT operators
and KK states in the AdS/CFT correspondence, and add some new comments on the
realization of the baryonic symmetries from the supergravity point of view.

</DOC>
<DOC>
<DOCNO> 169629 </DOCNO>
Algebra, Logic and Qubits: Quantum Abacus


  The canonical anticommutation relations (CAR) for fermion systems can be
represented by finite-dimensional matrix algebra, but it is impossible for
canonical commutation relations (CCR) for bosons. After description of more
simple case with representation of CAR and (bounded) quantum computational
networks via Clifford algebras in the paper are discussed CCR. For
representation of the algebra it is not enough to use quantum networks with
fixed number of qubits and it is more convenient to consider Turing machine
with essential operation of appending new cells for description of infinite
tape in finite terms --- it has straightforward generalization for quantum
case, but for CCR it is necessary to work with symmetrized version of the
quantum Turing machine. The system is called here quantum abacus due to
understanding analogy with the ancient counting devices (abacus).

</DOC>
<DOC>
<DOCNO> 100289 </DOCNO>
Classification of semisimple Hopf algebras of dimension 16


  In this paper we completely classify nontrivial semisimple Hopf algebras of
dimension 16. We also compute all the possible structures of the Grothendieck
ring of semisimple non-commutative Hopf algebras of dimension 16. Moreover, we
prove that non-commutative semisimple Hopf algebras of dimension p^n, p is
prime, cannot have a cyclic group of grouplikes.

</DOC>
<DOC>
<DOCNO> 70052 </DOCNO>
Deep inelastic leptoproduction of spin-one hadrons


  In this paper we analyze deep inelastic one-particle inclusive processes for
the case of spin-one targets or for the case of spin-one produced hadrons, such
as rho mesons. This allows the measurement of new distribution and
fragmentation functions not available in the spin-half case, and provides new
ways to probe functions otherwise difficult to measure. We will analyze only
contributions leading order in 1/Q, but we will include effects of the
transverse momentum of partons. We also include time-reversal odd functions.

</DOC>
<DOC>
<DOCNO> 71024 </DOCNO>
Precision measurements, extra generations and heavy neutrino


  The existence of extra chiral generations with all fermions heavier than
$M_Z$ is strongly disfavored by the precision electroweak data. The exclusion
of one additional generation of heavy fermions in SUSY extension of Standard
Model is less forbidden if chargino and neutralino have low degenerate masses
with $\Delta m \simeq 1$ GeV. However the data are fitted nicely even by a few
extra generations, if one allows neutral leptons to have masses close to 50
GeV. Such heavy neutrino can be searched in the reaction $e^+ e^- \to
N\bar{N}\gamma$ at LEP-200 with total final luminosity of $2600 pb^{-1}$.

</DOC>
<DOC>
<DOCNO> 99650 </DOCNO>
The Klein-Gordon's field. A counter-example of the classical limit


  We will study the Klein-Gordon's field with an homogeneous external
potential, which does not depend on $\h$. We will construct the Fock's space
corresponding to our problem and we will see that there are phenomena of
creation and anihilation of pairs particle-antiparticle. Finally, we will see
that in dimension 1, when $\h\to 0$, these phenomena disappear. However, in
dimension 2 or 3, when $\h\to 0$, the creation probability of
particle-antiparticle pairs is not zero.

</DOC>
<DOC>
<DOCNO> 122291 </DOCNO>
Radio Pulsars in the Magellanic Clouds


  We report the results of a survey of the Small Magellanic Cloud (SMC) for
radio pulsars conducted with the 20-cm multibeam receiver of the Parkes
64-meter telescope. This survey targeted a more complete region of the SMC than
a previous pulsar search and had an improvement in sensitivity by a factor of
about two for most pulsar periods. This survey is much more sensitive to fast
young pulsars (with P < 100 ms) and is the first survey of the SMC with any
sensitivity to millisecond pulsars. Two new pulsars were discovered in the
survey, one of which is located within the SMC. The number of pulsars found in
the survey is consistent with the expected number derived using several
methods. We also report the serendipitous discovery of a new pulsar in the 30
Doradus region of the Large Magellanic Cloud (LMC). These discoveries bring the
total number of rotation-powered pulsars currently known in the Magellanic
Clouds to eight. We have also made refined timing measurements for the new
discoveries as well as for three previously known LMC pulsars. The age
distribution of luminous Magellanic Cloud pulsars supports the conjecture that
pulsars younger than about 5 Myr are more luminous on average than older
pulsars.

</DOC>
<DOC>
<DOCNO> 121096 </DOCNO>
Massive warm dark matter


  Many independent high resolution simulations have indicated that the standard
collisionless cold dark matter model does not reproduce the structure of
observed present day galaxies well. Several possible solutions in the form of
modifications to the physics of the dark matter particles have been proposed.
One of the most promising is warm dark matter (WDM), particles with significant
thermal motion in the early universe. It is usually assumed that such particles
are relativistically decoupled particles with a mass of approximately 1 keV.
However, here we have investigated the possibility that much more massive
particles with highly non-thermal spectra could make up warm dark matter.
Several possible production mechanisms are reviewed and the only one found to
be viable is that the WDM is produced by the non-relativistic decay of some
massive species in the early universe. Such very massive warm dark matter could
possibly be detected in direct detection experiments, as opposed to standard
thermal warm dark matter.

</DOC>
<DOC>
<DOCNO> 84394 </DOCNO>
Behaviour of spin-1/2 particle around a charged black hole


  Dirac equation is separable in curved space-time and its solution was found
for both spherically and axially symmetric geometry. But most of the works were
done without considering the charge of the black hole. Here we consider the
spherically symmetric charged black hole background namely Reissner-Nordstrom
black hole. Due to presence of the charge of black-hole charge-charge
interaction will be important for the cases of incoming charged particle (e.g.
electron, proton etc.). Therefore both gravitational and electromagnetic gauge
fields should be introduced. Naturally behaviour of the particle will be
changed from that in Schwarzschild geometry. We compare both the solutions. In
the case of Reissner-Nordstrom black hole there is a possibility of
super-radiance unlike Schwarzschild case. We also check this branch of the
solution.

</DOC>
<DOC>
<DOCNO> 8981 </DOCNO>
Hydrodynamic Coupling of Two Brownian Spheres to a Planar Surface


  We describe direct imaging measurements of the collective and relative
diffusion of two colloidal spheres near a flat plate. The bounding surface
modifies the spheres' dynamics, even at separations of tens of radii. This
behavior is captured by a stokeslet analysis of fluid flow driven by the
spheres' and wall's no-slip boundary conditions. In particular, this analysis
reveals surprising asymmetry in the normal modes for pair diffusion near a flat
surface.

</DOC>
<DOC>
<DOCNO> 179024 </DOCNO>
Optical potentials for the antiproton nucleus interactions


  The nuclear interactions of atomic and low energy antiprotons are studied.
Measurements of level shifts and widths in the lightest elements are analyzed
and compared with new results obtained in heavy nuclei. Simple geometric
properties of antiproton - nucleus interactions are demonstrated. Upon this
background one finds some anomalies that indicate strong energy dependence in
the subthreshold antiproton - nucleon interactions. The use of of antiproton in
studies of the nuclear surface is briefly discussed.

</DOC>
<DOC>
<DOCNO> 170042 </DOCNO>
Superactivation of Bound Entanglement


  We show that, in a multi-party setting, two non-distillable (bound-entangled)
states tensored together can make a distillable state. This is an example of
true superadditivity of distillable entanglement. We also show that unlockable
bound-entangled states cannot be asymptotically separable, providing the first
proof that some states are truly bound-entangled in the sense of being both
non-distillable and non-separable asymptotically.

</DOC>
<DOC>
<DOCNO> 68328 </DOCNO>
Self-consistent approximations: application to a quasiparticle


  We generalize the concept of conserving,\Phi-derivable, approximations to
relativistic field theories. Treating the interaction field as a dynamical
degree of freedom, we derive the thermodynamical potential in terms of fully
dressed propagators, an approach which allows us to resolve the entropy of a
relativistic plasma into contributions from its interacting elementary
excitations. We illustrate the derivation for a hot QED plasma of massless
particles. We also discuss how the self-consistency of the treatment manifests
itself into relationships between the contributions from interaction and matter
fields.

</DOC>
<DOC>
<DOCNO> 80740 </DOCNO>
Numerical study of the Kugo-Ojima criterion and the Gribov problem in


  The Kugo-Ojima color confinement criterion, which is based on the BRST
symmetry of the continuum QCD is numerically tested by the lattice Landau gauge
simulation. We first discuss the Gribov copy problem and the BRST symmetry on
the lattice. The lattice Landau gauge can be formulated with options of the
gauge field definition, U(link)-linear type or log U type. The Kugo-Ojima
parameter u^a_b which is expected to be -1^a_b in the continuum theory is found
to be -0.7*1^a_b in the strong coupling region, and the magnitude is a little
less in the weak coupling region in log U type simulation. Those values are
weakened even further in U-linear type. The horizon function defined by
Zwanziger is evaluated in both types of gauge field and compared. The horizon
function in the log U version is larger than the other, but in the weak
coupling region, the expectation value of the horizon function is suggested to
be zero or negative.

</DOC>
<DOC>
<DOCNO> 118470 </DOCNO>
Iterative Maps with Hierarchical Clustering for the Observed Scales of


  We derive, in order of magnitude, the observed astrophysical and cosmological
scales in the Universe, from neutron stars to superclusters of galaxies, up to,
asymptotically, the observed radius of the Universe. This result is obtained by
introducing a recursive scheme of alternating hierachical mechanisms of
three-dimensional and two-dimensional close packings of gravitationally
interacting objects. The iterative scheme yields a rapidly converging geometric
sequence, which can be described as a hierarchical clustering of aggregates,
having the observed radius of the Universe as its fixed point.

</DOC>
<DOC>
<DOCNO> 9580 </DOCNO>
Microscopic Calculation of the Dielectric Susceptibility Tensor for


  In a Coulomb fluid confined to a domain $V$, the dielectric susceptibility
tensor $\chi_V$ depends on the shape of $V$, even in the thermodynamic
$V\to\infty$ limit. This paper deals with the classical two-dimensional
one-component plasma formulated in an elliptic $V$-domain, equilibrium
statistical mechanics is used. For the dimensionless coupling constant $\Gamma
=$ even positive integer, the mapping of the plasma onto a discrete
one-dimensional anticommuting-field theory provides a new sum rule. This sum
rule confirms the limiting value of $\chi_V$ predicted by macroscopic
electrostatics and gives the finite-size correction term to $\chi_V$.

</DOC>
<DOC>
<DOCNO> 151208 </DOCNO>
Comments on Perturbative Dynamics of Non-Commutative Yang-Mills Theory


  We study the U(N) non-commutative Yang-Mills theory at the one-loop
approximation. We check renormalizability and gauge invariance of the model and
calculate the one-loop beta function. The interaction of the SU(N) gauge bosons
with the U(1) gauge boson plays an important role in the consistency check. In
particular, the SU(N) theory by itself is not consistent. We also find that the
theta --> 0 limit of the U(N) theory does not converge to the ordinary SU(N) x
U(1) commutative theory, even at the planar limit. Finally, we comment on the
UV/IR mixing.

</DOC>
<DOC>
<DOCNO> 121197 </DOCNO>
Size-selective concentration of chondrules and other small particles in


  Size-selective concentration of particles in a weakly turbulent
protoplanetary nebula may be responsible for the initial collection of
chondrules and other constituents into primitive body precursors. This paper
presents the main elements of this process of turbulent concentration. In the
terrestrial planet region, both the characteristic size and size distribution
of chondrules are explained. "Fluffier" particles would be concentrated in
nebula regions which were at a lower gas density and/or more intensely
turbulent. The spatial distribution of concentrated particle density obeys
multifractal scaling}, suggesting a close tie to the turbulent cascade process.
This scaling behavior allows predictions of the probability distributions for
concentration in the protoplanetary nebula to be made. Large concentration
factors (>10^5) are readily obtained, implying that numerous zones of particle
density significantly exceeding the gas density could exist. If most of the
available solids were actually in chondrule sized particles, the ensuing
particle mass density would become so large that the feedback effects on gas
turbulence due to mass loading could no longer be neglected. This paper
describes the process, presenting its basic elements and some implications,
without including the effects of mass loading.

</DOC>
<DOC>
<DOCNO> 170704 </DOCNO>
Complete parameterization, and invariance, of diffusive quantum


  The state matrix $\rho$ for an open quantum system with Markovian evolution
obeys a master equation. The master equation evolution can be unraveled into
stochastic nonlinear trajectories for a pure state $P$, such that on average
$P$ reproduces $\rho$. Here we give for the first time a complete
parameterization of all diffusive unravelings (in which $P$ evolves
continuously but non-differentiably in time). We give an explicit measurement
theory interpretation for these quantum trajectories, in terms of monitoring
the system's environment. We also introduce new classes of diffusive
unravelings that are invariant under the linear operator transformations under
which the master equation is invariant. We illustrate these invariant
unravelings by numerical simulations. Finally, we discuss generalized gauge
transformations as a method of connecting apparently disparate descriptions of
the same trajectories by stochastic Schr\"odinger equations, and their
invariance properties.

</DOC>
<DOC>
<DOCNO> 68671 </DOCNO>
Radiative Corrections to the Hadronic Cross-Section Measurement at


  The hadronic invariant mass distribution for the process of electron-positron
annihilation into a pair of charged pions accompanied by a photon radiated from
the initial state has been studied for the region of DA$\Phi$NE energies. The
Born cross-section and the electromagnetic radiative corrections to it are
calculated for realistic conditions of the KLOE detector. The dependence on the
physical parameters which define the event selection is obtained.

</DOC>
<DOC>
<DOCNO> 116713 </DOCNO>
Quantum Maxwell Stresses and the Casimir Effect


  We evaluate the quantum correlators associated with the Maxwell field vacuum
distorted by the presence of plane parallel material surfaces. Regularization
is performed through the generalized zeta funtion technique. Results are
applied to a local analysis of the atractive and repulsive Casimir effect
through Maxwell stress tensor. Surface divergences are shown to cancel out when
stresses on both sides of the material surface are taken into account. Since an
atom can be considered as a probe of the local distortion of the quantum
vacuum, Casimir-Polder interactions between atoms and material surfaces are
also considered.

</DOC>
<DOC>
<DOCNO> 119329 </DOCNO>
Chandra Detection of an X-ray Flare from the Brown Dwarf LP 944-20


  We have detected a bright X-ray flare from the nearby brown dwarf LP 944-20
with the Chandra/ACIS-S. This is an old (500 Myr), rapidly rotating,
lithium-bearing M9 object, with a bolometric luminosity of 6e29 ergs cm-2 s-1.
It was only detected by Chandra during an X-ray flare of duration 1-2 hours
near the end of a 12.1 hour observation. The peak X-ray luminosity was
1.2(+0.5/-0.3)e26 ergs cm-2 s-1 in the brightest ~550 seconds, corresponding to
Lx/Lbol ~ 2e-4. A total of 2e29 ergs was released during the 43,773 sec
observation, giving a time-averaged Lx/Lbol ~ 7e-6. LP 944-20 was not detected
before the flare, with a 3 sigma upper limit on the emission at Lx/Lbol < 2e-6
(Lx<1e24 ergs cm-2 s-1). This is faint for a rapidly rotating late-type star,
and establishes a record lower limit to the quiescent flux about an order of
magnitude below the flux limit (and a factor of 5 below the Lx/Lbol limit)
placed on quiescent X-ray emission from the M8 dwarf VB 10. The inferred
flaring duty cycle is comparable to that measured via variable H-alpha emission
for other late M-type, fully convective stars.

</DOC>
<DOC>
<DOCNO> 9935 </DOCNO>
Hydrostatic theory of superfluid 3He-B


  The determination of the texture of the order parameter is important for
understanding many experiments in superfluid 3He. In addition to reviewing the
theory of textures in superfluid 3He-B we give several new results, in
particular on the surface parameters in the Ginzburg-Landau region and bulk
parameters at arbitrary temperature. Special attention is paid to separate the
results that are valid at all temperatures from those which are limited to the
Ginzburg-Landau region. We study the validity of a trivial strong-coupling
model, where the energy gap of the weak-coupling theory is scaled by a
temperature dependent factor. We compare the theory with several experiments.
For some quantities the theory seems to work fine and we extract the
dipole-dipole interaction parameter from the measurements.

</DOC>
<DOC>
<DOCNO> 100985 </DOCNO>
Reeh-Schlieder Defeats Newton-Wigner: On alternative localization


  Many of the "counterintuitive" features of relativistic quantum field theory
have their formal root in the Reeh-Schlieder theorem, which in particular
entails that local operations applied to the vacuum state can produce any state
of the entire field. It is of great interest, then, that I.E. Segal and, more
recently, G. Fleming (in a paper entitled "Reeh-Schlieder Meets Newton-Wigner")
have proposed an alternative "Newton-Wigner" localization scheme that avoids
the Reeh-Schlieder theorem. In this paper, I reconstruct the Newton-Wigner
localization scheme and clarify the limited extent to which it avoids the
counterintuitive consequences of the Reeh-Schlieder theorem. I also argue that
neither Segal nor Fleming has provided a coherent account of the physical
meaning of Newton-Wigner localization.

</DOC>
<DOC>
<DOCNO> 151479 </DOCNO>
Confinement and the Short Type I' Flux Tube


  We show that the recent world-sheet analysis of the quantum fluctuations of a
short flux tube in type II string theory leads to a simple and precise
description of a pair of stuck D0branes in an orientifold compactification of
the type I' string theory. The existence of a stable type I' flux tube of
sub-string-scale length is a consequence of the confinement of quantized flux
associated with the scalar dualized ten-form background field strength *F_{10},
evidence for a -2brane in the BPS spectrum of M theory. Using heterotic-type I
duality, we infer the existence of an M2brane of finite width O(\sqrt{\alpha'})
in M-theory, the strong coupling resolution of a spacetime singularity in the
D=9 twisted and toroidally compactified E_8 x E_8 heterotic string. This
phenomenon has a bosonic string analog in the existence of a stable short
electric flux tube arising from the confinement of photons due to tachyon field
dynamics. The appendix clarifies the appearance of nonperturbative states and
enhanced gauge symmetry in toroidal compactifications of the type I' string. We
account for all of the known disconnected components of the moduli space of
theories with sixteen supercharges, in striking confirmation of heterotic-type
I duality.

</DOC>
<DOC>
<DOCNO> 85210 </DOCNO>
Waveforms for Gravitational Radiation from Cosmic String Loops


  We obtain general formulae for the plus- and cross- polarized waveforms of
gravitational radiation emitted by a cosmic string loop in transverse,
traceless (synchronous, harmonic) gauge. These equations are then specialized
to the case of piecewise linear loops, and it is shown that the general
waveform for such a loop is a piecewise linear function. We give several simple
examples of the waveforms from such loops. We also discuss the relation between
the gravitational radiation by a smooth loop and by a piecewise linear
approximation to it.

</DOC>
<DOC>
<DOCNO> 174561 </DOCNO>
Octupole deformations in actinides at high spins within the cranking


  The cranked Skyrme III effective Hamiltonian is applied for the analysis of
the rotational dependence of the quadrupole and octupole moments in Ra, Th, and
U isotopes. A comparison of the intrinsic electric dipole moments calculated in
the model with available experimental and theoretical values is presented. It
is found that the non-axial octupole deformation $Y_{32}$ becomes favorable at
high spins for the actinide nuclei.

</DOC>
<DOC>
<DOCNO> 123082 </DOCNO>
A search for previously unrecognised metal-poor subdwarfs in the


  We have identified 317 stars included in the Hipparcos astrometric catalogue
which have parallaxes measured to a precision of better than 15%, and whose
location in the (M_V, (B-V)_T) diagram implies a metallicity comparable to or
less than that of the intermediate-abundance globular cluster, M5. We have
undertaken an extensive literature search to locate Stromgren, Johnson/Cousins
and Walraven photometry for over 120 stars. In addition, we present new UBVRI
photometry of 201 of these candidate halo stars, together with similar data for
a further 14 known metal-poor subdwarfs. Those observations provide the first
extensive dataset of RI photometry of metal-poor, main-sequence stars with
well-determined trigonometric parallaxes. Finally, we have obtained
intermediate-resolution optical spectroscopy of 175 stars. We are able to
estimate abundances for 270 stars. The overwhelming majority have near-solar
abundance, with their inclusion in the present sample stemming from errors in
the colours listed in the Hipparcos catalogue. Only 44 stars show consistent
evidence of abundances below [Fe/H]= -1.0. Nine are additions to the small
sample of metal-poor subdwarfs with accurate photometry. We consider briefly
the implication of these results for cluster main-sequence fitting.

</DOC>
<DOC>
<DOCNO> 13168 </DOCNO>
Relativistic corrections in magnetic systems


  We present a weak-relativistic limit comparison between the Kohn-Sham-Dirac
equation and its approximate form containing the exchange coupling, which is
used in almost all relativistic codes of density-functional theory. For these
two descriptions, an exact expression of the Dirac Green's function in terms of
the non-relativistic Green's function is first derived and then used to
calculate the effective Hamiltonian, i.e., Pauli Hamiltonian, and effective
velocity operator in the weak-relativistic limit. We point out that, besides
neglecting orbital magnetism effects, the approximate Kohn-Sham-Dirac equation
also gives relativistic corrections which differ from those of the exact
Kohn-Sham-Dirac equation. These differences have quite serious consequences: in
particular, the magnetocrystalline anisotropy of an uniaxial ferromagnet and
the anisotropic magnetoresistance of a cubic ferromagnet are found from the
approximate Kohn-Sham-Dirac equation to be of order $1/c^2$, whereas the
correct results obtained from the exact Kohn-Sham-Dirac equation are of order
$1/c^4$ . We give a qualitative estimate of the order of magnitude of these
spurious terms.

</DOC>
<DOC>
<DOCNO> 116834 </DOCNO>
Driver Accelerator Design for the 10 kW Upgrade of the Jefferson Lab IR


  An upgrade of the Jefferson Lab IR FEL is now under construction. It will
provide 10 kW output light power in a wavelength range of 2-10 microns. The FEL
will be driven by a modest-sized 80-210 MeV, 10 mA energy-recovering
superconducting RF (SRF) linac. Stringent phase space requirements at the
wiggler, low beam energy, and high beam current subject the design to numerous
constraints. These are imposed by the need for both transverse and longitudinal
phase space management, the potential impact of collective phenomena (space
charge, wakefields, beam break-up (BBU), and coherent synchrotron radiation
(CSR)), and interactions between the FEL and the accelerator RF system. This
report addresses these issues and presents an accelerator design solution
meeting the requirements imposed by physical phenomena and operational
necessities.

</DOC>
<DOC>
<DOCNO> 80863 </DOCNO>
Topology in full QCD with 2 colours at finite temperature and density


  We present preliminary results about topology and several other quantities at
non-zero baryon density and finite temperature in full QCD with N_c=2.

</DOC>
<DOC>
<DOCNO> 69545 </DOCNO>
Monopoles, affine algebras and the gluino condensate


  We examine the low-energy dynamics of four-dimensional supersymmetric gauge
theories and calculate the values of the gluino condensate for all simple gauge
groups. By initially compactifying the theory on a cylinder we are able to
perform calculations in a controlled weakly-coupled way for small radius. The
dominant contributions to the path integral on the cylinder arise from magnetic
monopoles which play the role of instanton constituents. We find that the
semi-classically generated superpotential of the theory is the affine Toda
potential for an associated twisted affine algebra. We determine the
supersymmetric vacua and calculate the values of the gluino condensate. The
number of supersymmetric vacua is equal to c_2, the dual Coxeter number, and in
each vacuum the monopoles carry a fraction 1/c_2 of topological charge. As the
results are independent of the radius of the circle, they are also valid in the
strong coupling regime where the theory becomes decompactified. In this way we
obtain values for the gluino condensate which for the classical gauge groups
agree with previously known ``weak coupling instanton'' expressions (but not
with the ``strong coupling instanton'' calculations). This detailed agreement
provides further evidence in favour of the recently advocated resolution of the
the gluino condensate puzzle. We also make explicit predictions for the gluino
condensate for the exceptional groups.

</DOC>
<DOC>
<DOCNO> 69264 </DOCNO>
Weak hyperon decays in heavy baryon chiral perturbation theory:


  The complete renormalization of the weak Lagrangian to chiral order q^2 in
heavy baryon chiral perturbation theory is performed using heat kernel
techniques. The results are compared with divergences appearing in the
calculation of Feynman graphs for the nonleptonic hyperon decay Lambda -> p
pi^- and an estimate for the size of the counterterm contributions to the
s-wave amplitudes in nonleptonic hyperon decays is given.

</DOC>
<DOC>
<DOCNO> 150639 </DOCNO>
Non-perturbative string connections


  We discuss the duality between two type I compactifications to four
dimensions and an heterotic construction with spontaneous breaking of the N=4
supersymmetry to N=2. This duality allows us to gain insight into the
non-perturbative properties of these models. Through the analysis of the
gravitational corrections, we then investigate the connections between
four-dimensional, N=2 M-theory vacua constructed as orbifolds of type II,
heterotic, and type I strings.

</DOC>
<DOC>
<DOCNO> 14135 </DOCNO>
Test of Bell's Inequality using the Spin Filter Effect in Ferromagnetic


  A theoretical proposal for testing Bell's inequality in mesoscopic systems is
presented. We show that the entanglement of two electron spins can be detected
in the spin filter effect in the mesoscopic semiconductor / ferromagnetic
semiconductor / semiconductor junction. The current-current correlation
function is calculated by use of the quantum scattering theory and we compare
it with the local hidden variable theory. We also discuss the influence of an
imperfect spin filter and derive the condition to see the violation of Bell's
inequality experimentally.

</DOC>
<DOC>
<DOCNO> 119807 </DOCNO>
Non-LTE treatment of molecules in the photospheres of cool stars


  We present a technique to treat systems with very many levels, like
molecules, in non-LTE. This method is based on a superlevel formalism coupled
with rate operator splitting. Superlevels consist of many individual levels
that are assumed to be in LTE relative to each other. The usage of superlevels
reduces the dimensionality of the rate equations dramatically and, thereby,
makes the problem computationally more easily treatable. Our superlevel
formalism retains maximum accuracy by using direct opacity sampling (dOS) when
calculating the radiative transitions and the opacities. We developed this
method in order to treat molecules in cool dwarf model calculations in non-LTE.
Cool dwarfs have low electron densities and a radiation field that is far from
a black body radiation field, both properties may invalidate the conditions for
the common LTE approximation. Therefore, the most important opacity sources,
the molecules, need to be treated in non-LTE. As a case study we applied our
method to carbon monoxide. We find that our method gives accurate results since
the conditions for the superlevel method are very well met for molecules. Due
to very high collisional cross sections with hydrogen, and the high densities
of H_2 the population of CO itself shows no significant deviation from LTE.

</DOC>
<DOC>
<DOCNO> 9568 </DOCNO>
Moment of inertia of a trapped superfluid gas of Fermions


  The moment of inertia Q of a trapped superfluid gas of atomic Fermions (6Li)
is calculated as a function of the temperature. At zero temperature the moment
of inertia takes on the irrotational flow value. Only for T very close to Tc
rigid rotation is attained. It is proposed that future measurements of the
rotational energy will unambiguously reveal whether the system is in a
superfluid state or not.

</DOC>
<DOC>
<DOCNO> 71692 </DOCNO>
(Mis)Understanding the Atmospheric Neutrino Anomaly


  The apparent attenuation of muon neutrinos relative to electron neutrinos is
a bit too low to be compatible with the most popular values of $\Delta m^{2}$.
Fits to $R(E_{\nu})$ favor values of $\Delta m^{2}>0.1$ eV$^{2}$. The fit
minimized by the Super Kamioka group in estimating neutrino oscillation
parameters neglects systematic errors. The fit is dominated by systematic
effects. The data being combined in recent fits may not be compatible since
there appear to be significant variations in the properties of the data with
time. A simple two component neutrino oscillation with $\Delta m^{2}$ in the
range of 10$^{-3}$ to 10$^{-2}$ eV$^{2}$ seems unable to account for the
observations.

</DOC>
<DOC>
<DOCNO> 13791 </DOCNO>
Observation of coupled normal heat and matter transport in a simple


  We introduce the first simple mechanical system that shows fully realistic
transport behavior while still being exactly solvable at the level of
equilibrium statistical mechanics. The system under consideration is a Lorentz
gas with fixed freely-rotating circular scatterers which scatter point
particles via perfectly rough collisions. Upon imposing either a temperature
gradient and/or a chemical potential gradient, a stationary state is attained
for which local thermal equilibrium holds. Transport in this system is normal,
in the sense that the transport coefficients which characterize the flow of
heat and matter are finite in the thermodynamic limit. Moreover, the two flows
are non-trivially coupled, satisfying Onsager's reciprocity relations to within
numerical accuracy.

</DOC>
<DOC>
<DOCNO> 69652 </DOCNO>
The chiral symmetry restoration phase transition in baryon spectrum


  It is shown that in the large $N_c$ limit the light baryon spectrum exhibits
the chiral restoration phase transition at high enough excitation energy. Such
a phase transition is evidenced by the systematical parity doublets observed in
the upper part of $N$ and $\Delta$ spectra.

</DOC>
<DOC>
<DOCNO> 12269 </DOCNO>
Damping and revivals of collective oscillations in a finite-temperature


  We utilize a two-gas model to simulate collective oscillations of a
Bose-Einstein condensate at finite temperatures. The condensate is described
using a generalized Gross-Pitaevskii equation, which is coupled to a thermal
cloud modelled by a Monte Carlo algorithm. This allows us to include the
collective dynamics of both the condensed and non-condensed components
self-consistently. We simulate quadrupolar excitations, and measure the damping
rate and frequency as a function of temperature. We also observe revivals in
condensate oscillations at high temperatures, and in the thermal cloud at low
temperature. Extensions of the model to include non-equilibrium effects and
describe more complex phenomena are discussed.

</DOC>
<DOC>
<DOCNO> 80858 </DOCNO>
Light quark masses for dynamical, non-perturbatively O(a) improved


  We present results for the light quark masses in lattice QCD with two
degenerate flavours of dynamical fermions. We used configurations generated by
the UKQCD and QCDSF collaborations at six different combinations of beta and
kappa_sea.

</DOC>
<DOC>
<DOCNO> 119951 </DOCNO>
The Effect of Gasdynamics on the Structure of Dark Matter Halos


  Adaptive SPH and N-body simulations were carried out to study the effect of
gasdynamics on the structure of dark matter halos that result from the
gravitational instability and fragmentation of cosmological pancakes. Such
halos resemble those formed in a hierarchically clustering CDM universe and
serve as a test-bed model for studying halo dynamics. With no gas, the density
profile is close to the universal profile identified previously from N-body
simulations of structure formation in CDM. When gas is included, the gas in the
halo is approximately isothermal, and both the dark matter and the gas have
singular central density profiles which are steeper than that of the dark
matter with no gas. This worsens the disagreement between observations of
constant density cores in cosmological halos and the singular ones found in
simulations. We also find that the dark matter velocity distribution is less
isotropic than found by N-body simulations of CDM, because of the strongly
filamentary substructure.

</DOC>
<DOC>
<DOCNO> 121869 </DOCNO>
Accretion and Outflow in the Circinus AGN


  The first VLBI images of water maser emission in the Circinus Galaxy AGN show
both an accretion disk and outflow 0.1 to 1 pc from the central engine. The
maser traces a warped, edge-on accretion disk between radii of about 0.1 and
0.4 pc that is bound by a 1.3x10^6 Msun central mass. The rotation curve is
somewhat flatter than a Keplerian rotation law and is consistent with a disk
mass on the order of 10^5 Msun. Clumpy substructure may display a kinematic
signature consistent with spiral arms. Away from the disk, a second population
of water masers traces broadly a bipolar, wide-angle outflow that contains
(bullet-like) clumps ejected from a region centered on the central engine and
<0.1 pc in radius. Out to a radius of about 0.4 pc, the warp of the accretion
disk appears to channel the outflow, the orientation of which on the sky
coincides with the orientation of the known kiloparsec-scale ionization cone.
Beyond this radius, the flow crosses the disk and truncates it. This suggests
that the current accretion event and associated disk-outflow geometry have a
lifetime on the order of 10^7 years.

</DOC>
<DOC>
<DOCNO> 9644 </DOCNO>
Thermal correlators of anyons in two dimensions


  The anyon fields have trivial $\alpha$-commutator for $\alpha$ not integer.
For integer $\alpha$ the commutators become temperature-dependent operator
valued distributions. The $n$-point functions do not factorize as for quasifree
states.

</DOC>
<DOC>
<DOCNO> 119485 </DOCNO>
The Origin of the Solar Flare Waiting-Time Distribution


  It was recently pointed out that the distribution of times between solar
flares (the flare waiting-time distribution) follows a power law, for long
waiting times. Based on 25 years of soft X-ray flares observed by Geostationary
Operational Environmental Satellite (GOES) instruments it is shown that 1. the
waiting-time distribution of flares is consistent with a time-dependent Poisson
process, and 2. the fraction of time the Sun spends with different flaring
rates approximately follows an exponential distribution. The second result is a
new phenomenological law for flares. It is shown analytically how the observed
power-law behavior of the waiting times originates in the exponential
distribution of flaring rates. These results are argued to be consistent with a
non-stationary avalanche model for flares.

</DOC>
<DOC>
<DOCNO> 39869 </DOCNO>
Diffraction at the LHC - antishadow scattering?


  Numerical predictions for the global characteristics of proton-proton
interactions are given for the LHC energy. Possibilities for the discovery of
the antishadow scattering mode and its physical implications are discussed.

</DOC>
<DOC>
<DOCNO> 151217 </DOCNO>
Complexified Gravity in Noncommutative Spaces


  The presence of a constant background antisymmetric tensor for open strings
or D-branes forces the space-time coordinates to be noncommutative. This effect
is equivalent to replacing ordinary products in the effective theory by the
deformed star product. An immediate consequence of this is that all fields get
complexified. The only possible noncommutative Yang-Mills theory is the one
with U(N) gauge symmetry. By applying this idea to gravity one discovers that
the metric becomes complex. We show in this article that this procedure is
completely consistent and one can obtain complexified gravity by gauging the
symmetry $U(1,D-1)$ instead of the usual $SO(1,D-1)$. The final theory depends
on a Hermitian tensor containing both the symmetric metric and antisymmetric
tensor. In contrast to other theories of nonsymmetric gravity the action is
both unique and gauge invariant. The results are then generalized to
noncommutative spaces.

</DOC>
<DOC>
<DOCNO> 102694 </DOCNO>
Exact Groups, Induced Ideals, and Fell Bundles


  Given a C*-algebra B which is graded over a discrete group G we consider
ideals of B which are invariant under the projections onto each of the grading
subspaces. If G is exact and the standard conditional expectation of B is
faithful we show that all such ideals are induced, i.e. are generated by their
intersection with the unit fiber algebra. This result is derived from a
generalization to the context of Fell bundles of a Theorem by Kirchberg and
Wasserman according to which a group is exact if and only if its reduced
C*-algebra is exact.

</DOC>
<DOC>
<DOCNO> 101986 </DOCNO>
Integer Algorithms to Solver Linear Equations and Systems


  The present work includes some of the author's original researches on integer
solutions of equations and linear systems: The notion of "general integer
solution" of a linear equation with two unknowns is extended to linear
equations with n unknowns and then, to linear systems. The proprieties of the
general integer solution are determined (both of a linear and system). Seven
original integer algorithms (two for linear equations, and five for linear
systems) are exposed. The algorithms are strictly proved and an example for
each of them is given. These algorithms can be easily implemented in the
computer.

</DOC>
<DOC>
<DOCNO> 12898 </DOCNO>
Distribution of resonance widths in localized tight-binding models


  We numerically analyze the distribution of scattering resonance widths in
one- and quasi-one dimensional tight binding models, in the localized regime.
We detect and discuss an algebraic decay of the distribution, similar, though
not identical, to recent theoretical predictions.

</DOC>
<DOC>
<DOCNO> 151798 </DOCNO>
D-brane Solitons in Supersymmetric Sigma-Models


  Massive D=4 N=2 supersymmetric sigma models typically admit domain wall
(Q-kink) solutions and string (Q-lump) solutions, both preserving 1/2
supersymmetry. We exhibit a new static 1/4 supersymmetric `kink-lump' solution
in which a string ends on a wall, and show that it has an effective realization
as a BIon of the D=4 super DBI-action. It is also shown to have a
time-dependent Q-kink-lump generalization which reduces to the Q-lump in a
limit corresponding to infinite BI magnetic field. All these 1/4 supersymmetric
sigma-model solitons are shown to be realized in M-theory as calibrated, or
`Q-calibrated', M5-branes in an M-monopole background.

</DOC>
<DOC>
<DOCNO> 40636 </DOCNO>
The first year of the BABAR experiment at PEP-II


  The BABAR detector, situated at the SLAC PEP-II asymmetric e^+e^- collider,
has been recording data at energies on and around the Upsilon(4S) resonance
since May 1999. In this paper, we briefly describe the PEP-II B Factory and the
BABAR detector. The performance presently achieved by the experiment in the
areas of tracking, vertexing, calorimetry and particle identification is
reviewed. Analysis concepts that are used in the various papers submitted to
this conference are also discussed.

</DOC>
<DOC>
<DOCNO> 170476 </DOCNO>
Quantum computation in a one-dimensional crystal lattice with NMR force


  A proposal for a scalable, solid-state implementation of a quantum computer
is presented. Qubits are fluorine nuclear spins in a solid crystal of
fluorapatite [Ca_5 F(PO_4)_3] with resonant frequencies separated by a large
field gradient. Quantum logic is accomplished using nuclear-nuclear dipolar
couplings with decoupling and selective recoupling RF pulse sequences. Magnetic
resonance force microscopy is used for readout. As many as 300 qubits can be
implemented in the laboratory extremes of T=10 mK and B_0=20 T with the
existing sensitivity of force microscopy.

</DOC>
<DOC>
<DOCNO> 8805 </DOCNO>
On the Mooij Rule


  Weak localization leads to the same correction to both the conductivity and
the electron-phonon coupling constant $\lambda$ (and $\lambda_{tr}$).
Consequently the temperature dependence of the (thermal) electrical resistivity
is decreasing as the conductivity is decreasing due to weak localization, which
results in the decrease of the temperature coefficient of resistivity (TCR)
with increasing the residual resistivity. When $\lambda$ is approaching zero,
only residual resistivity part remains and gives rise to the negative TCR.
Accordingly, the Mooij rule is a manifestation of weak localization correction
to the conductivity and the electron-phonon interaction. This study may provide
a new means of probing the phonon-mechanism in exotic superconductors.

</DOC>
<DOC>
<DOCNO> 122971 </DOCNO>
Parsec-Scale Jets and Tori in Seyfert Galaxies


  What causes the dichotomy between very powerful and very weak radio emission
from AGNs? Perhaps the engines are the same but the jets get disrupted by dense
ISM in radio-quiet objects, or else the engines are intrinsically different
with jet power scaling with, say, black hole spin. To distinguish, one can look
for interaction between the jets and the NLR and measure the jet speed close to
the core using VLBI, before environmental effects become important. We find
that in radio-quiet AGN, the jets appear slower and have a greater tendency to
bend, and that one-sidedness and flat-spectrum cores are probably due to
obscuration.

</DOC>
<DOC>
<DOCNO> 116334 </DOCNO>
An Essay on the Relationship Between the Mind and the Physical World


  A non-technical argument is presented that there is a link between the mind
and the physical world in modern physics. Special relativity, general
relativity, quantum mechanics, statistical mechanics, and other areas of
physics are explored. Each area is found to support the existence of a link
between the mind and the physical world. Research from psychology is also
presented indicating that there is a role for the discipline of psychology in
delineating the nature of this link.

</DOC>
<DOC>
<DOCNO> 150446 </DOCNO>
D-branes on Orbifolds with Discrete Torsion And Topological Obstruction


  We find the orbifold analog of the topological relation recently found by
Freed and Witten which restricts the allowed D-brane configurations of Type II
vacua with a topologically non-trivial flat $B$-field. The result relies in
Douglas proposal -- which we derive from worldsheet consistency conditions --
of embedding projective representations on open string Chan-Paton factors when
considering orbifolds with discrete torsion. The orbifold action on open
strings gives a natural definition of the algebraic K-theory group -- using
twisted cross products -- responsible for measuring Ramond-Ramond charges in
orbifolds with discrete torsion. We show that the correspondence between
fractional branes and Ramond-Ramond fields follows in an interesting fashion
from the way that discrete torsion is implemented on open and closed strings.

</DOC>
<DOC>
<DOCNO> 117852 </DOCNO>
Dark Halo and Disk Galaxy Scaling Laws in Hierarchical Universes


  We use cosmological N-body/gasdynamical simulations that include star
formation and feedback to examine the proposal that scaling laws between the
total luminosity, rotation speed, and angular momentum of disk galaxies reflect
analogous correlations between the structural parameters of their surrounding
dark matter halos. The numerical experiments follow the formation of
galaxy-sized halos in two Cold Dark Matter dominated universes: the standard
Omega=1 CDM scenario and the currently popular LCDM model. We find that the
slope and scatter of the I-band Tully-Fisher relation are well reproduced in
the simulations, although not, as proposed in recent work, as a result of the
cosmological equivalence between halo mass and circular velocity: large
systematic variations in the fraction of baryons that collapse to form galaxies
and in the ratio between halo and disk circular velocities are observed in our
numerical experiments. The Tully-Fisher slope and scatter are recovered in this
model as a direct result of the dynamical response of the halo to the assembly
of the luminous component of the galaxy. We conclude that models that neglect
the self-gravity of the disk and its influence on the detailed structure of the
halo cannot be used to derive meaningful estimates of the scatter or slope of
the Tully-Fisher relation. Our models fail, however, to match the zero-point of
the Tully-Fisher relation, as well as that of the relation linking disk
rotation speed and angular momentum. These failures can be traced,
respectively, to the excessive central concentration of dark halos formed in
the Cold Dark Matter cosmogonies we explore and to the formation of galaxy
disks as the final outcome of a sequence of merger events. (abridged)

</DOC>
<DOC>
<DOCNO> 118977 </DOCNO>
Evidence for Newly Synthesized Lithium in Interstellar Space


  As a part of a study on the variation in the 7Li/6Li ratio, high signal to
noise, high resolution spectroscopy of Li I (6708 Angstroms) and K I (4044
Angstroms) were obtained toward zeta and o Per. The lithium isotope shift is
approximately the same as its fine structure splitting (0.158 Angstroms),
resulting in a blend of the 7Li and 6Li lines. Use of the K I line as a
velocity template allowed a straightforward determination of the lithium
isotopic ratio.
  Our high resolution observations show remarkably disparate isotope ratios:
7Li/6Li = 1 0.6 +/- 2.9 toward zeta Per and 3.6 +/- 0.6 and 1.7 +/- 0.3 toward
o Per. While the results toward zeta Per are consistent with the meteoritic
value, the ratio toward o Per's clouds suggest recent Galactic cosmic ray
spallation. This is the first clear and unambiguous evidence for an
interstellar 7Li/6Li ratio that differs dramatically from the Solar System
value. The low ratio indicates a higher cosmic ray flux toward o Per than
toward zeta Per. A higher flux of cosmic rays toward o Per was suggested
earlier in a study of OH and HD chemistry (Federman, Weber, & Lambert 1996, ApJ
463, 181).
  The total lithium abundances and the K/Li ratio are useful in placing the
7Li/6Li ratio into context. We obtained total lithium abundances of (12.2 +/-
2.2) x 10^(-10) toward zeta Per and (9.8 +/- 3.5) x 10^(-10) toward o Per. The
columns of K I and Li I yielded K/Li ratios that revealed no discernable trend.
Since a Li isotope ratio ~2 toward o Per suggests newly processed lithium, the
comparable total Li abundances and K/Li ratios are unexpected.

</DOC>
<DOC>
<DOCNO> 122463 </DOCNO>
Off-Beam Gamma-Ray Pulsars and Unidentified EGRET Sources in the Gould


  We investigate whether gamma-ray pulsars viewed at a large angle to the
neutron star magnetic pole could contribute to the new population of galactic
unidentified EGRET sources associated with the Gould Belt. The faint, soft
nature of these sources is distinctly different from both the properties of
unidentified EGRET sources along the galactic plane and of the known gamma-ray
pulsars. We explore the possibility, within the polar cap model, that some of
these sources are emission from pulsars seen at lines of sight that miss both
the bright gamma-ray cone beams and the radio beam. The off-beam gamma-rays
come from high-altitude curvature emission of primary particles, are radiated
over a large solid angle and have a much softer spectrum than that of the main
beams. We estimate that the detectability of such off-beam emission is about a
factor of 4-5 higher than that of the on-beam emission. At least some of the
radio-quiet Gould Belt sources detected by EGRET could therefore be such
off-beam gamma-ray pulsars. GLAST should be able to detect pulsations in most
of these sources.

</DOC>
<DOC>
<DOCNO> 117807 </DOCNO>
The radio luminosity of persistent X-ray binaries


  We summarise all the reported detections of, and upper limits to, the radio
emission from persistent (i.e. non-transient) X-ray binaries. A striking result
is a common mean observed radio luminosity from the black hole candidates
(BHCs) in the Low/Hard X-ray state and the neutron-star Z sources on the
horizontal X-ray branch. This implies a common mean intrinsic radio luminosity
to within a factor of twenty five (or less, if there is significant Doppler
boosting of the radio emission). Unless coincidental, these results imply a
physical mechanism for jet formation which requires neither a black hole event
horizon or a neutron star surface. As a whole the populations of Atoll and
X-ray pulsar systems are less luminous by factors of >5 and >10 at radio
wavelengths than the BHCs and Z sources (while some Atoll sources have been
detected, no high-field X-ray pulsar has ever been reliably detected as a radio
source). We suggest that all of the persistent BHCs and the Z sources generate,
at least sporadically, an outflow with physical dimensions > 1e12cm, i.e.
significantly larger than the binary separations of most of the systems. We
compare the physical conditions of accretion in each of the types of persistent
X-ray binary and conclude that a relatively low (<1e10 G) magnetic field
associated with the accreting object, and a high (>0.1 Eddington) accretion
rate and/or dramatic physical change in the accretion flow, are required for
formation of a radio-emitting outflow or jet.

</DOC>
<DOC>
<DOCNO> 85055 </DOCNO>
Time-Dependent Automorphism Inducing Diffeomorphisms In Vacuum Bianchi


  We investigate the set of spacetime general coordinate transformations
(G.C.T.) which leave the line element of a generic Bianchi Type Geometry,
quasi-form invariant; i.e. preserve manifest spatial Homogeneity. We find that
these G.C.T.'s, induce special time-dependent automorphic changes, on the
spatial scale factor matrix $\gamma_{\alpha\beta}(t)$ -along with corresponding
changes on the lapse function $N(t)$ and the shift vector $N^{\alpha}(t)$.
These changes, which are Bianchi Type dependent, form a group and are, in
general, different from those induced by the group SAut(G) -advocated in
earlier investigations as the relevant symmetry group-, they are used to
simplify the form of the line element -and thus simplify Einstein's equations
as well-, without losing generality.
  As far as this simplification procedure is concerned, the transformations
found, are proved to be essentialy unique. For the case of Bianchi Types II and
V, where the most general solutions are known -Taub's and Joseph's,
respectively-, it is explicitly verified that our transformations and only
those, suffice to reduce the generic line element, to the previously known
forms. It becomes thus possible, -for these Types- to give in closed form, the
most general solution, containing all the necessary ``gauge'' freedom.

</DOC>
<DOC>
<DOCNO> 122022 </DOCNO>
Testing the origin of the gamma-ray background


  Fluctuations of the gamma-ray background (GRB) are investigated. It is
assumed that the GRB is produced by discrete sources. Two basic classes of
objects as dominant contributors to the GRB are considered: a) blazars and b)
starburst galaxies. Predicted logN-logS counts are calculated for these two
models. To produce substantial fraction of the XRB, both classes of sources are
subject to strong evolution. Since blazars are several orders of magnitude more
luminous than starburst galaxies, their number required to produce the GRB is
much smaller than the number of starburst galaxies. In effect, fluctuations of
the GRB in the blazar model are relatively high. It is shown that moderate
improvement in the measurements of the GRB flux will allow us to discriminate
beteween these models.

</DOC>
<DOC>
<DOCNO> 8092 </DOCNO>
Universal quantum limits on single channel information, entropy and heat


  We show that the recently discovered universal upper bound on the thermal
conductance of a single channel comprising particles obeying arbitrary
fractional statistics is in fact a consequence of a more general universal
upper bound, involving the averaged entropy and energy currents of a single
channel connecting heat reservoirs with arbitrary temperatures and chemical
potentials. The latter upper bound in turn leads, via Holevo's theorem, to a
universal (i.e., statistics independent) upper bound on the optimum capacity
for classical information transmission down a single, wideband quantum channel.

</DOC>
<DOC>
<DOCNO> 71850 </DOCNO>
QED Radiative Correction for the Single-W Production using a Parton


  A parton shower method for the photonic radiative correction is applied to
the single W-boson production processes. The energy scale for the evolution of
the parton shower is determined so that the correct soft-photon emission is
reproduced. Photon spectra radiated from the partons are compared with those
from the exact matrix elements, and show a good agreement. Possible errors due
to a inappropriate energy-scale selection or due to the ambiguity of energy
scale determination are also discussed, particularly for the measurements on
triple gauge-couplings.

</DOC>
<DOC>
<DOCNO> 170252 </DOCNO>
The Kapitza - Dirac effect


  The Kapitza - Dirac effect is the diffraction of a well - collimated particle
beam by a standing wave of light. Why is this interesting? Comparing this
situation to the introductory physics textbook example of diffraction of a
laser beam by a grating, the particle beam plays the role of the incoming wave
and the standing light wave the role of the material grating, highlighting
particle - wave duality. Apart from representing such a beautiful example of
particle - wave duality, the diffracted particle beams are coherent. This
allows the construction of matter interferometers and explains why the Kapitza
- Dirac effect is one of the workhorses in the field of atom optics. Atom
optics concerns the manipulation of atomic waves in ways analogous to the
manipulation of light waves with optical elements. The excitement and activity
in this new field of physics stems for a part from the realisation that the
shorter de Broglie wavelengths of matter waves allow ultimate sensitivities for
diffractive and interferometric experiments that in principle would far exceed
their optical analogues. Not only is the Kapitza - Dirac effect an important
enabling tool for this field of physics, but diffraction peaks have never been
observed for electrons, for which is was originally proposed in 1933. Why has
this not been observed? What is the relation between the interaction of laser
light with electrons and the interaction of laser light with atoms, or in other
words what is the relation between the ponderomotive potential and the
lightshift potential? Would it be possible to build interferometers using the
Kapitza - Dirac effect for other particles? These questions will be addressed
in this paper.

</DOC>
<DOC>
<DOCNO> 10040 </DOCNO>
First Steps in Glass Theory


  This paper is an introduction to some of the main present issues in the
theory of structural glasses. After recalling a few experimental facts, it
gives a short account of the analogy between fragile glasses and the mean field
discontinuous spin glasses. The many valley picture is presented, and a brief
account of recent attempts to obtain quantitative results from first principle
computations is summarised.

</DOC>
<DOC>
<DOCNO> 12927 </DOCNO>
Diffusion-Reorganized Aggregates: Attractors in Diffusion Processes?


  A process based on particle evaporation, diffusion and redeposition is
applied iteratively to a two-dimensional object of arbitrary shape. The
evolution spontaneously transforms the object morphology, converging to
branched structures. Independently of initial geometry, the structures found
after long time present fractal geometry with a fractal dimension around 1.75.
The final morphology, which constantly evolves in time, can be considered as
the dynamic attractor of this evaporation-diffusion-redeposition operator. The
ensemble of these fractal shapes can be considered to be the {\em dynamical
equilibrium} geometry of a diffusion controlled self-transformation process.

</DOC>
<DOC>
<DOCNO> 150749 </DOCNO>
Double Symmetries in Field Theories


  In the paper a concept of a double symmetry is introduced, and its
qualitative characteristics and rigorous definitions are given. We describe two
ways to construct the double-symmetric field theories and present an example
demonstrating the high efficiency of one of them. In noting the existing
double-symmetric theories we draw attention at a dual status of the group
$SU(2)_{L} \otimes SU(2)_{R}$ as a secondary symmetry group, and in this
connexion we briefly discuss logically possible aspects of the $P$-violation in
weak interactions.

</DOC>
<DOC>
<DOCNO> 99799 </DOCNO>
Complemented subspaces of locally convex direct sums of Banach spaces


  We show that a complemented subspace of a locally convex direct sum of an
uncountable collection of Banach spaces is a locally convex direct sum of
complemented subspaces of countable subsums. As a corollary we prove that a
complemented subspace of a locally convex direct sum of arbitrary collection of
$\ell_{1}(\Gamma)$-spaces is isomorphic to a locally convex direct sum of
$\ell_{1}(\Gamma)$-spaces.

</DOC>
<DOC>
<DOCNO> 8385 </DOCNO>
Evaluation of the quantitative prediction of a trend reversal on the


  In January 1999, the authors published a quantitative prediction that the
Nikkei index should recover from its 14 year low in January 1999 and reach
$\approx 20500$ a year later. The purpose of the present paper is to evaluate
the performance of this specific prediction as well as the underlying model:
the forecast, performed at a time when the Nikkei was at its lowest (as we can
now judge in hindsight), has correctly captured the change of trend as well as
the quantitative evolution of the Nikkei index since its inception. As the
change of trend from sluggish to recovery was estimated quite unlikely by many
observers at that time, a Bayesian analysis shows that a skeptical (resp.
neutral) Bayesian sees her prior belief in our model amplified into a posterior
belief 19 times larger (resp. reach the 95% level).

</DOC>
<DOC>
<DOCNO> 101828 </DOCNO>
On contractively complemented subspaces of separable L_1-preduals


  Let X be an L_1-predual space and let K be a countable linearly independent
subset of the extreme points of its closed dual ball. It is shown that if the
norm-closed linear span Y of K is w^*-closed in X^*, then Y is the range of a
w^*-continuous contractive projection in X^*. This result is applied in order
to provide new and simpler proofs of the results of Lazar, Lindenstrauss and
Zippin on the embedding of C(K) spaces into X.

</DOC>
<DOC>
<DOCNO> 119826 </DOCNO>
Is there ERE in bright nebulae?


  In 1986 Witt & Schild studied the optical emission of selected bright
nebulae. Comparison of the data to a model led the authors to conclude the
nebulae have too high a level of I-band emission to be explained solely by the
scattering of starlight. The excess is explained as a broad band I emission
which originates in the nebulae. This phenomenum is known as Extended Red
Emission (ERE).
  Given Witt & Schild's data, the model they employed, and the estimate of
observational errors, I've reached a different conclusion: Witt & Schild's
observations are compatible with classical scattering and therefore cannot be
used to prove the existence of ERE.

</DOC>
<DOC>
<DOCNO> 117952 </DOCNO>
A Priori Probability Distribution of the Cosmological Constant


  In calculations of the probability distribution for the cosmological
constant, it has been previously assumed that the a priori probability
distribution is essentially constant in the very narrow range that is
anthropically allowed. This assumption has recently been challenged. Here we
identify large classes of theories in which this assumption is justified.

</DOC>
<DOC>
<DOCNO> 12449 </DOCNO>
Temperature dependence of Fano line shapes in a weakly coupled


  We report the temperature dependence of the zero-bias conductance of a
single-electron transistor in the regime of weak coupling between the quantum
dot and the leads. The Fano line shape, convoluted with thermal broadening,
provides a good fit to the observed asymmetric Coulomb charging peaks. However,
the width of the peaks increases more rapidly than expected from the thermal
broadening of the Fermi distribution in a temperature range for which Fano
interference is unaffected. The intrinsic width of the resonance extracted from
the fits increases approximately quadratically with temperature. Above about
600 mK the asymmetry of the peaks decreases, suggesting that phase coherence
necessary for Fano interference is reduced with increasing temperature.

</DOC>
<DOC>
<DOCNO> 11753 </DOCNO>
Exact solutions for interacting boson systems under rotation


  We study a class of interacting, harmonically trapped boson systems at
angular momentum L. The Hamiltonian leaves a L-dimensional subspace invariant,
and this permits an explicit solution of several eigenstates and energies for a
wide class of two-body interactions

</DOC>
<DOC>
<DOCNO> 69356 </DOCNO>
Brane-Universe in Six Dimensions


  Growing non-singular solution of 6-dimensional Einstein equations for the
4-brane in infinite transversal 2-space is found. This solution provides
gravitational trapping of matter and 4-dimensional gravity on the brane without
extra delta-like source. The suitable solution exists in the case of the
(2+4)-space and not exists for the (1+5)-signature.

</DOC>
<DOC>
<DOCNO> 10906 </DOCNO>
Reentrance of the induced diamagnetism in gold-niobium proximity


  We discuss the magnetic response of gold-niobium proximity cylinders in the
temperature range 100 \mu K<T<9 K. The temperature dependence of the
susceptibility in the diamagnetic regime is described well by the
quasiclassical Eilenberger theory including an elastic mean-free path l. In the
mesoscopic regime, the temperature dependence of the reentrant paramagnetic
susceptibility \chi_para(T) \propto \exp[-L/3\xi^d_N(T)] is governed by the
dirty limit coherence length \xi^d_N(T)=\sqrt{1/3\xi_N l_N}, with \xi_N the
clean limit coherence length obtained from breakdown field measurements and l_N
the measured mean-free path in the gold layer. At T=100 \mu K, \chi_para
compensates about 1/5 of the induced diamagnetic susceptibility in gold.

</DOC>
<DOC>
<DOCNO> 70188 </DOCNO>
Two-mixing texture for three active neutrinos


  The conjecture that among three massive neutrinos $\nu_1, \nu_2, \nu_3$ there
is no direct mixing between $\nu_1$ and $\nu_3$ leads to a two-mixing texture
for three active neutrinos $\nu_e, \nu_\mu, \nu_\tau$. This texture, much
discussed previously, is neatly consistent with the observed deficits of solar
$\nu_e$'s and atmospheric $\nu_\mu$'s, but (without extra mixing with at least
one sterile neutrino $\nu_s$) predicts no LSND effect for accelerator
$\nu_\mu$'s. In this option, the masses $m^2_1\stackrel{<}{\sim} m^2_2 <<
m^2_3$ are readily estimated. The characteristic feature of the two-mixing
neutrino texture that {\it only the close neighbours in the hierarchy of
massive neutrinos $\nu_1, \nu_2, \nu_3$ mix significantly} may be physically
meaningful. Going out from the notion of mixing matrix we construct an
intrinsic occupation-number operator whose {\it eigenvalues} 0, 1, 2 {\it
numerate the three generations of massive neutrinos}. Analogical constructions
work also for charged leptons as well as for up and down quarks.

</DOC>
<DOC>
<DOCNO> 68693 </DOCNO>
Noncommutative Geometry as a Regulator


  We give a perturbative quantization of space-time $R^4$ in the case where the
commutators $C^{{\mu}{\nu}}=[X^{\mu},X^{\nu}]$ of the underlying algebra
generators are not central . We argue that this kind of quantum space-times can
be used as regulators for quantum field theories . In particular we show in the
case of the ${\phi}^4$ theory that by choosing appropriately the commutators
$C^{{\mu}{\nu}}$ we can remove all the infinities by reproducing all the
counter terms . In other words the renormalized action on $R^4$ plus the
counter terms can be rewritten as only a renormalized action on the quantum
space-time $QR^4$ . We conjecture therefore that renormalization of quantum
field theory is equivalent to the quantization of the underlying space-time
$R^4$ .

</DOC>
<DOC>
<DOCNO> 170645 </DOCNO>
Separable approximations of density matrices of composite quantum


  We investigate optimal separable approximations (decompositions) of states
rho of bipartite quantum systems A and B of arbitrary dimensions MxN following
the lines of Ref. [M. Lewenstein and A. Sanpera, Phys. Rev. Lett. 80, 2261
(1998)]. Such approximations allow to represent in an optimal way any density
operator as a sum of a separable state and an entangled state of a certain
form. For two qubit systems (M=N=2) the best separable approximation has a form
of a mixture of a separable state and a projector onto a pure entangled state.
We formulate a necessary condition that the pure state in the best separable
approximation is not maximally entangled. We demonstrate that the weight of the
entangled state in the best separable approximation in arbitrary dimensions
provides a good entanglement measure. We prove in general for arbitrary M and N
that the best separable approximation corresponds to a mixture of a separable
and an entangled state which are both unique. We develop also a theory of
optimal separable approximations for states with positive partial transpose
(PPT states). Such approximations allow to decompose any density operator with
positive partial transpose as a sum of a separable state and an entangled PPT
state. We discuss procedures of constructing such decompositions.

</DOC>
<DOC>
<DOCNO> 71822 </DOCNO>
Hydrodynamics of relativisic systems with broken continuous symmetries


  We show how hydrodynamics of relativistic system with broken continuous
symmetry can be constructed using the Poisson bracket technique. We illustrate
the method on the example of relativistic superfluids.

</DOC>
<DOC>
<DOCNO> 11270 </DOCNO>
Rotational Dynamics of Vortices in Confined Bose-Einstein Condensates


  We derive the frequency of precession and conditions for stability for a
quantized vortex in a single-component and a two-component Bose-Einstein
condensate. The frequency of precession is proportional to the gradient of the
free energy with respect to displacement of the vortex core. In a two-component
system, it is possible to achieve a local minimum in the free energy at the
center of the trap. The presence of such a minimum implies the existence of a
region of energetic stability where the vortex cannot escape and where one may
be able to generate a persistent current.

</DOC>
<DOC>
<DOCNO> 71676 </DOCNO>
A Summary from the Theorist's Point of View


  1. Introduction - 2. Astrophysics and Cosmology - 3. Neutrino Oscillations -
4. Higgs and New Physics Searches - 5. Flavour Physics and CP Violation - 6.
QCD - 7. Heavy Ion Collisions - 8. Outlook

</DOC>
<DOC>
<DOCNO> 151402 </DOCNO>
Bulk Witten Indices and the Number of Normalizable Ground States in


  This note addresses the question of the number of normalizable vacuum states
in supersymmetric quantum mechanics with sixteen supercharges and arbitrary
semi-simple compact gauge group, up to rank three. After evaluating certain
contour integrals obtained by appropriately adapting BRST deformation
techniques we propose novel rational values for the bulk indices. Our results
demonstrate that an asymptotic method for obtaining the boundary contribution
to the index, originally due to Green and Gutperle, fails for groups other than
SU(N). We then obtain likely values for the number of ground states of these
systems. In the case of orthogonal and symplectic groups our finding is
consistent with recent conjectures of Kac and Smilga, but appears to contradict
their result in the case of the exceptional group G_2.

</DOC>
<DOC>
<DOCNO> 99774 </DOCNO>
Geometrical techniques for the N-dimensional Quantum Euclidean Spaces


  We briefly report our application of a version of noncommutative geometry to
the quantum Euclidean space $R^N_q$, for any $N \ge 3$; this space is covariant
under the action of the quantum group $SO_q(N)$, and two covariant differential
calculi are known on it. More precisely, we describe how to construct in a
Cartan `moving-frame formalism' the metric, two covariant derivatives, the
Dirac operator, the frame, the inner derivations dual to the frame elements,
for both of these calculi. The components of the frame elements in the basis of
differentials provide a `local realization' of the
Faddeev-Reshetikhin-Takhtadjan generators of $U_q^{\pm}(so(N))$.

</DOC>
<DOC>
<DOCNO> 100440 </DOCNO>
Open problems for the superKdV equations


  After a review of the basic results concerning the $N=1,2$ supersymmetric
extensions of the Korteweg-de Vries equation, with a pedagogical presentation
of the superspace techniques, we discuss some basic open problems mainly in
relation with the N=2 extensions.

</DOC>
<DOC>
<DOCNO> 152208 </DOCNO>
Colours associated to non simply-laced Lie algebras and exact S-matrices


  A new set of exact scattering matrices in 1+1 dimensions is proposed by
solving the bootstrap equations. Extending earlier constructions of colour
valued scattering matrices this new set has its colour structure associated to
non simply-laced Lie algebras. This in particular leads to a coupling of
different affine Toda models whose fusing structure has to be matched in a
suitable manner. The definition of the new S-matrices is motivated by the
semi-classical particle spectrum of the non simply-laced Homogeneous
Sine-Gordon (HSG) models, which are integrable perturbations of WZNW cosets. In
particular, the S-matrices of the simply-laced HSG models are recovered as a
special case.

</DOC>
<DOC>
<DOCNO> 150423 </DOCNO>
Vacuum Polarization in QED with World-Line Methods


  Motivated by several recent papers on string-inspired calculations in QED, we
here present our own use of world-line techniques in order to calculate the
vacuum polarization and effective action in scalar and spinor QED with external
arbitrary constant electromagnetic field configuration.

</DOC>
<DOC>
<DOCNO> 13802 </DOCNO>
The +/-J Spin Glass: Effects of Ground State Degeneracy


  We perform Monte Carlo simulations of the Ising spin glass at low temperature
in three dimensions with a +/-J distribution of couplings. Our results display
crossover scaling between T=0 behavior, where the order parameter distribution
P(q) becomes trivial for L -> $\infty$, and finite-T behavior, where the
non-trivial part of P(q) has a much weaker dependence on the size L, and is
possibly size independent.

</DOC>
<DOC>
<DOCNO> 121822 </DOCNO>
Linear Analysis of the Hall Effect in Protostellar Disks


  The effects of Hall electromotive forces (HEMFs) on the linear stability of
protostellar disks are examined. Earlier work on this topic focused on axial
field and perturbation wavenumbers. Here we treat the problem more generally.
Both axisymmetric and nonaxisymmetric cases are investigated. Though seldom
explicitly included in calculations, HEMFs appear to be important whenever
Ohmic dissipation is. They allow for the appearance of electron whistler waves,
and since these have right-handed polarization, a helicity factor is also
introduced into the stability problem. This factor is the product of the
components of the angular velocity and magnetic field along the perturbation
wavenumber, and it is destabilizing when negative. Unless the field and angular
velocity are exactly aligned, it is always possible to find destabilizing
wavenumbers. HEMFs can destabilize any differential rotation law, even those
with angular velocity increasing outward. Regardless of the sign of the angular
velocity gradient, the maximum growth rate is always given in magnitude by the
local Oort A value of the disk, as in the standard magnetorotational
instability. The role of Hall EMFs may prove crucial to understanding how
turbulence is maintained in the ``low state'' of eruptive disk systems.

</DOC>
<DOC>
<DOCNO> 121236 </DOCNO>
Evidence for Massive Black Holes in Nearby Galactic Nuclei


  Masses of black holes in nearby galactic nuclei can be measured in a variety
of ways, using stellar and gaseous kinematics. Reliable black hole masses are
known for several dozen objects, so that demographic questions can start to be
addressed with some confidence. Prospects for the near future are discussed
briefly.

</DOC>
<DOC>
<DOCNO> 100275 </DOCNO>
On the Relation Between Pommaret and Janet Bases


  In this paper the relation between Pommaret and Janet bases of polynomial
ideals is studied. It is proved that if an ideal has a finite Pommaret basis
then the latter is a minimal Janet basis. An improved version of the related
algorithm for computation of Janet bases, initially designed by Zharkov, is
described. For an ideal with a finite Pommaret basis, the algorithm computes
this basis. Otherwise, the algorithm computes a Janet basis which need not be
minimal. The obtained results are generalized to linear differential ideals.

</DOC>
<DOC>
<DOCNO> 10967 </DOCNO>
The critical behavior of frustrated spin models with noncollinear order


  We study the critical behavior of frustrated spin models with noncollinear
order, including stacked triangular antiferromagnets and helimagnets. For this
purpose we compute the field-theoretic expansions at fixed dimension to six
loops and determine their large-order behavior. For the physically relevant
cases of two and three components, we show the existence of a new stable fixed
point that corresponds to the conjectured chiral universality class. This
contradicts previous three-loop field-theoretical results but is in agreement
with experiments.

</DOC>
<DOC>
<DOCNO> 10058 </DOCNO>
Few-Particle Effects in Semiconductor Quantum Dots: Observation of


  We investigate experimentally and theoretically few-particle effects in the
optical spectra of single quantum dots (QDs). Photo-depletion of the QD
together with the slow hopping transport of impurity-bound electrons back to
the QD are employed to efficiently control the number of electrons present in
the QD. By investigating structurally identical QDs, we show that the spectral
evolutions observed can be attributed to intrinsic, multi-particle-related
effects, as opposed to extrinsic QD-impurity environment-related interactions.
  From our theoretical calculations we identify the distinct transitions
related to excitons and excitons charged with up to five additional electrons,
as well as neutral and charged biexcitons.

</DOC>
<DOC>
<DOCNO> 151158 </DOCNO>
Comments on the Morita Equivalence


  It is known that noncommutative Yang-Mills theory with periodical boundary
conditions on torus at the rational value of the noncommutativity parameter is
Morita equivalent to the ordinary Yang-Mills theory with twisted boundary
conditions on dual torus. We present simple derivation of this fact. We
describe one-to-one correspondence between and gauge invariant observables in
these two theories. In particular, we show that under Morita map Polyakov loops
in the ordinary YM theory go to the open noncommutative Wilson loops discovered
by Ishibashi, Iso, Kawai and Kutazawa.

</DOC>
<DOC>
<DOCNO> 102631 </DOCNO>
On the quantum cohomology of Fano bundles over projective spaces


  In their paper "Quantum cohomology of projective bundles over $P^n$" (Trans.
Am. Math. Soc. (1998)350:9 3615-3638) Z.Qin and Y.Ruan introduce interesting
techniques for the computation of the quantum ring of manifolds which are
projectivized bundles over projective spaces; in particular, in the case of
splitting bundles they prove under some restrictions the formula of Batyrev
about the quantum ring of toric manifolds. Here we prove the formula of Batyrev
on the quantum Chern-Leray equation for a large class of splitting bundles.

</DOC>
<DOC>
<DOCNO> 69203 </DOCNO>
Dynamics and properties of chiral cosmic strings in Minkowski space


  Chiral cosmic strings are produced naturally at the end of inflation in
supersymmetric models where the symmetry is broken via a D-term. Consequently
in such theories, where both inflation and cosmic strings contribute to the
density and CMBR (microwave background) perturbations, it is necessary to
understand the evolution of chiral cosmic string networks. We study the
dynamics of chiral cosmic strings in Minkowski space and comment on a number of
differences with those of Nambu-Goto strings. To do this we follow the work of
Carter and Peter who showed that the equations of motion for chiral cosmic
strings reduce to a wave equation and two constraints, only one of which is
different from the familiar Nambu-Goto constraints. We study chiral string loop
solutions consisting of many harmonics and determine their self-intersection
probabilities, and comment on the possible cosmological significance of these
results.

</DOC>
<DOC>
<DOCNO> 71648 </DOCNO>
t-channel production of heavy charged leptons


  We study the pair production of heavy charged exotic leptons at e+ e-
colliders in the SU(2)_L x SU(2)_I x U(1)_Y model. This gauge group is a
subgroup of the grand unification group E6; SU(2)_I commutes with the electric
charge operator, and the three corresponding gauge bosons are electrically
neutral. In addition to the standard photon and Z boson contributions, we also
include the contributions from extra neutral gauge bosons. A t-channel
contribution due to W_I-boson exchange, which is unsuppressed by mixing angles,
is quite important. We calculate the left-right and forward-backward
asymmetries, and discuss how to differentiate different models.

</DOC>
<DOC>
<DOCNO> 68002 </DOCNO>
The Past and Future of S-Matrix Theory


  Contents: 1. Introduction. 2. The Early Years. 2.1 Living Without Field
Theory. 2.2 Initial Postulates. 2.3 Further Postulates. 2.4 QCD and a Final
Postulate. 2.5 Analyticity in Field Theory. 3. Axiomatic S-Matrix Theory. 3.1
Unitarity, Bubble Diagrams and Landau Diagrams. 3.2 The Landau Equations and
the ``$+~ \alpha$'' Condition. 3.3 Macrocausality and Essential Support. 3.4
The Structure Theorem. 3.5 Local Discontinuity Formulae. 3.6 Good and Bad
Functions and the Steinmann Relations. 3.7 Global Discontinuity Formulae. 3.8
CPT, Hermitian Analyticity, etc. 3.9 Holonomy. 4. Asymptotic S-Matrix Theory.
4.1 The Elastic Scattering Asymptotic Dispersion Relation. 4.2 Multiparticle
Kinematics and Analyticity Domains. 4.3 Multiparticle Asymptotic Dispersion
Relations. 4.4 Classification of Multiple Discontinuities. 5. Multi-Regge
Theory. 5.1 Partial-Wave Expansions. 5.2 Froissart-Gribov Continuations.
Sommerfeld-Watson Representations. 5.4 Reggeon Unitarity. 6. Reggeon Field
Theory. 6.1 Pomeron Phase-Space and the Effective Lagrangian. 6.2 The Critical
Pomeron. 6.3 The Super-Critical Pomeron. 7. QCD and the Critical Pomeron. 7.1
Reggeon Diagrams in QCD. 7.2 Color Superconductivity and the Super-Critical
Pomeron. 7.3 Quark Saturation and an Infra-Red Fixed Point. 7.4 Uniqueness of
the S-Matrix ?

</DOC>
<DOC>
<DOCNO> 169901 </DOCNO>
On quantum evolution as a parallel transport


  Time-dependent quantum evolution is described by an algebraic connection on a
$C^\infty(R)$-module of sections of a $C^*$-algebra (or Hilbert) fibre bundle.

</DOC>
<DOC>
<DOCNO> 9139 </DOCNO>
Magnetic Geometry and the Confinement of Electrically Conducting Plasmas


  We develop an effective field theory approach to inspect the electromagnetic
interactions in an electrically neutral plasma, with an equal number of
negative and positive charge carriers. We argue that the static equilibrium
configurations within the plasma are topologically stable solitons, that
describe knotted and linked fluxtubes of helical magnetic fields.

</DOC>
<DOC>
<DOCNO> 84715 </DOCNO>
Cyclical Behaviour in Early Universe Cosmologies


  We study early universe cosmologies derived from a scalar-tensor action
containing cosmological constant terms and massless fields. The governing
equations can be written as a dynamical system which contains no past or future
asymptotic equilibrium states (i.e. no sources nor sinks). This leads to
dynamics with very interesting mathematical behaviour such as the existence of
heteroclinic cycles. The corresponding cosmologies have novel characteristics,
including cyclical and bouncing behaviour possibly indicating chaos. We discuss
the connection between these early universe cosmologies and those derived from
the low-energy string effective action.

</DOC>
<DOC>
<DOCNO> 11983 </DOCNO>
Spin glass freezing in Kondo lattice compounds


  It is presented a theory that describes a spin glass phase at finite
temperatures in Kondo lattice systems with an additional RKKY interaction
represented by long range, random couplings among localized spins like in the
Sherrington- Kirkpatrick (SK) spin glass model. The problem is studied within
the functional integral formalism where the spin operators are represented by
bilinear combinations of fermionic (anticommuting) Grassmann variables. The
Kondo and spin glass transitions are both described with the mean field like
static ansatz that reproduces good results in the two well known limits. At
high temperatures and low values of the Kondo coupling there is a paramagnetic
(disordered) phase with vanishing Kondo and spin glass order parameters. By
lowering the temperature a second order transition line is found at Tsg to a
spin glass phase. For larger values of the Kondo coupling there is a second
order transition line at roughly Tk to a Kondo ordered state. For T<Tsg the
transition between the Kondo and spin glass phases becomes first order.

</DOC>
<DOC>
<DOCNO> 10605 </DOCNO>
Charged colloids at low ionic strength: macro- or microphase separation?


  Phase separation in charged systems may involve the replacement of critical
points by microphase separated states, or charge-density-wave states. A density
functional theory for highly charged colloids at low ionic strength is
developed to examine this possibility. It is found that the lower critical
solution point is most susceptible to microphase separation. Moreover the
tendency can be quantified, and related to the importance of small ion entropy
in suppressing phase separation at low added salt. The theory also gives
insights into the colloid structure factor in these systems.

</DOC>
<DOC>
<DOCNO> 70887 </DOCNO>
The $\mu$ and soft masses from the intermediate scale brane with


  The proton decay problem and the negative brane tension problem in the
original Randall-Sundrum model can be resolved by interpreting the Planck scale
brane as the visible sector brane. The hierarchy problem is resolved with
supersymmetry, and the TeV scales for soft masses and $\mu$ in supersymmetric
models are generated by the physics at the intermediate scale ($\sim
10^{11-13}$ GeV) brane.

</DOC>
<DOC>
<DOCNO> 152456 </DOCNO>
No van Dam-Veltman-Zakharov Discontinuity for Supergravity in AdS Space


  Adding explicit mass terms for the spin 2 and spin 3/2 field of N=1 anti-de
Sitter supergravity, the limit M --> 0 for these mass terms is smooth: there is
no van Dam-Veltman-Zakharov mass discontinuity in the propagators when the
cosmological constant is non-vanishing.

</DOC>
<DOC>
<DOCNO> 118471 </DOCNO>
Combination Frequencies in the Fourier Spectra of White Dwarfs


  Combination frequencies are observed in the Fourier spectra of pulsating DA
and DB white dwarfs. They appear at sums and differences of frequencies
associated with the stellar gravity-modes. Brickhill (1992) proposed that the
combination frequencies result from mixing of the eigenmode signals as the
surface convection zone varying in depth when undergoing pulsation. This depth
changes cause time-dependent thermal impedance, which mix different harmonic
frequencies in the light curve.
  Following Brickhill's proposal, we developed analytical expressions to
describe the amplitudes and phases of these combination frequencies. The
parameters that appear in these expressions are: the depth of the stellar
convection zone when at rest, the sensitivity of this depth towards changes in
stellar effective temperature, the inclination angle of the stellar pulsation
axis with respect to the line of sight, and lastly, the spherical degrees of
the eigenmodes involved in the mixing. Adopting reasonable values for these
parameters, we apply our expressions to a DA and a DB variable white dwarf. We
find reasonable agreement between theory and observation, though some
discrepancies remain unexplained. We show that it is possible to identify the
spherical degrees of the pulsation modes using the combination frequencies.

</DOC>
<DOC>
<DOCNO> 170571 </DOCNO>
Contradiction of Quantum Mechanics with Local Hidden Variables for


  We demonstrate a contradiction of quantum mechanics with local hidden
variable theories for continuous variable quadrature phase amplitude
(``position'' and ``momentum'') measurements, by way of a violation of a Bell
inequality. For any quantum state, this contradiction is lost for situations
where the quadrature phase amplitude results are always macroscopically
distinct. We show that for optical realisations of this experiment, where one
uses homodyne detection techniques to perform the quadrature phase amplitude
measurement, one has an amplification prior to detection, so that macroscopic
fields are incident on photodiode detectors. The high efficiencies of such
detectors may open a way for a loophole-free test of local hidden variable
theories.

</DOC>
<DOC>
<DOCNO> 11332 </DOCNO>
Inequivalence of ensembles in statistical mechanics


  For studying the thermodynamic properties of systems using statistical
mechanics we propose an ensemble that lies in between the familiar canonical
and microcanonical ensembles. From a comparative study of these ensembles we
conclude that all these ensembles may not yield the same results even in the
thermodynamic limit except at high temperatures. An investigation of the
coupling between systems suggest that the state of thermodynamic equilibrium is
a special case of statistical equilibrium. As a byproduct of this analysis we
have obtained a general form for probability density function in an interval.

</DOC>
<DOC>
<DOCNO> 102231 </DOCNO>
M\'ethode des orbites et formules du caract\`ere pour les


  Let G be a non-connected reductive real Lie group. In this paper, I
parametrize the set of irreductible tempered characters of G. Afterwards, I
describe these characters by means of some ``Kirillov's formulas'', using the
descent method near each elliptic element in G.
  If G is linear and connected, the parameters that I use are ``final basic''
parameters in the sense of Knapp and Zuckerman.

</DOC>
<DOC>
<DOCNO> 150392 </DOCNO>
Pair Production of charged vector bosons in supercritical magnetic


  The thermodynamic properties of an ideal gas of charged vector bosons (with
mass m and charge e) is studied in a strong external homogeneous magnetic field
no greater than the critical value B_{cr}=m^2/e. The thermodynamic potential,
after appropriate analytic continuation, is then used in the study of the
spontaneous production of charged spin-one boson pairs from vacuum in the
presence of a supercritical homogeneous magnetic field at finite temperature.

</DOC>
<DOC>
<DOCNO> 67708 </DOCNO>
QED radiative corrections to virtual Compton scattering


  The QED radiative corrections to virtual Compton scattering (reaction $e p
\to e p \gamma$) are calculated to first order in $\alpha_{em} \equiv e^2 / 4
\pi$. A detailed study is presented for the one-loop virtual corrections and
for the first order soft-photon emission contributions. Furthermore, a full
numerical calculation is given for the radiative tail, corresponding with
photon emission processes, where the photon energy is not very small compared
with the lepton momenta. We compare our results with existing works on elastic
electron-proton scattering, and show for the $e p \to e p \gamma$ reaction how
the observables are modified due to these first order QED radiative
corrections. We show results for both unpolarized and polarized observables of
the virtual Compton scattering in the low energy region (where one is sensitive
to the generalized polarizabilities of the nucleon), as well as for the deeply
virtual Compton scattering.

</DOC>
<DOC>
<DOCNO> 99814 </DOCNO>
Holomorphic Vector Bundles, Knots and the Rozansky-Witten Invariants


  Link invariants, for 3-manifolds, are defined in the context of the
Rozansky-Witten theory. To each knot in the link one associates a holomorphic
bundle over a holomorphic symplectic manifold X. The invariants are evaluated
for b_{1}(M) \geq 1 and X Hyper-Kaehler. To obtain invariants of Hyper-Kaehler
X one finds that the holomorphic vector bundles must be hyper-holomorphic. This
condition is derived and explained. Some results for X not Hyper-Kaehler are
presented.

</DOC>
<DOC>
<DOCNO> 151950 </DOCNO>
Clifford algebra as quantum language


  We suggest Clifford algebra as a useful simplifying language for present
quantum dynamics. Clifford algebras arise from representations of the
permutation groups as they arise from representations of the rotation groups.
Aggregates using such representations for their permutations obey Clifford
statistics. The vectors supporting the Clifford algebras of permutations and
rotations are plexors and spinors respectively. Physical spinors may actually
be plexors describing quantum ensembles, not simple individuals. We use
Clifford statistics to define quantum fields on a quantum space-time, and to
formulate a quantum dynamics-field-space-time unity that evades the
compactification problem. The quantum bits of history regarded as a quantum
computation seem to obey a Clifford statistics.

</DOC>
<DOC>
<DOCNO> 69009 </DOCNO>
Introduction to the GiNaC Framework for Symbolic Computation within the


  The traditional split-up into a low level language and a high level language
in the design of computer algebra systems may become obsolete with the advent
of more versatile computer languages. We describe GiNaC, a special-purpose
system that deliberately denies the need for such a distinction. It is entirely
written in C++ and the user can interact with it directly in that language. It
was designed to provide efficient handling of multivariate polynomials,
algebras and special functions that are needed for loop calculations in
theoretical quantum field theory. It also bears some potential to become a more
general purpose symbolic package.

</DOC>
<DOC>
<DOCNO> 101231 </DOCNO>
Modularity of the Rankin-Selberg L-series, and multiplicity one for


  A fundamental question, first raised by Langlands, is to know whether the
Rankin-Selberg product of two (not necessarily holomorphic) cusp forms f and g
is modular, i.e., if there exists an automorphic form f box g on GL(4)/Q whose
standard L-function equals L^*(s, f x g) after removing the ramified and
archimedean factors. The first main result of this paper is to answer it in
the affirmative, in fact with the base field Q replaced by any number field F.
Our proof uses a mixture of converse theorems, base change and descent, and it
also appeals to the local regularity properties of Eisenstein series and the
scalar products of their truncations.
  One of the applications of this result is that the space of cusp forms on
SL(2) has multiplicity one. Concretely this means the following: If f, g are
newforms of holomorphic or Maass type with trivial character such that the
squares of the p-th coeficients of f and g are the same at almost all primes
p, then g must be a twist of f by a quadratic Dirichlet character.

</DOC>
<DOC>
<DOCNO> 68591 </DOCNO>
Exclusive production of pion pairs in gamma^* gamma collisions at large


  We perform a QCD analysis of the exclusive production of two mesons in
gamma^* gamma collisions in the kinematical domain of large photon virtuality Q
and small hadronic invariant mass W. This reaction is dominated by a scale
invariant mechanism which factorizes into a perturbative subprocess, gamma^*
gamma --> q qbar or gamma^* gamma --> g g, and a generalized two-meson
distribution amplitude. We develop in detail the phenomenology of this process
at e^+ e^- colliders. Using a simple model for the two-pion distribution
amplitude, based on its general properties, we estimate the cross section for
the kinematics accessible at BABAR, BELLE, CLEO and LEP.

</DOC>
<DOC>
<DOCNO> 170630 </DOCNO>
String Matching in ${\tilde O}(\sqrt{n}+\sqrt{m})$ Quantum Time


  We show how to determine whether a given pattern p of length m occurs in a
given text t of length n in ${\tilde O}(\sqrt{n}+\sqrt{m})$\footnote{${\tilde
O}$ allows for logarithmic factors in m and $n/m$} time, with inverse
polynomial failure probability. This algorithm combines quantum searching
algorithms with a technique from parallel string matching, called {\em
Deterministic Sampling}.

</DOC>
<DOC>
<DOCNO> 9910 </DOCNO>
Anomalous tricritical behaviour in the coil-globule transition of a


  We investigate a model of self-avoiding walk exhibiting a first-order
coil-globule transition. This first-order nature, unravelled through the
coexistence of distinct coil and globule populations, has observable
consequences on the scaling properties. A thorough analysis of the size
dependence of the mean radius of gyration evidences a breakdown of the plain
tricritical scaling behaviour. In some regimes, anomalous exponents are
observed in the transition region and logarithmic corrections arise along the
coexistence curve.

</DOC>
<DOC>
<DOCNO> 123260 </DOCNO>
Demographics of Blazars


  We discuss the preliminary results of an extensive effort to address the
fundamental, and yet un-answered, question that can be trivialized as: ``are
there more blue or red blazars?''. This problematic is tightly connected with
the much debated issue of the unified picture(s) of radio-loud AGNs, which in
turn revolves around the existence, and the properties of relativistic jets. We
address this question by comparing -- simultaneously -- the properties of the
collection of heterogeneously selected samples that are available now, with the
predictions of a set of plausible unifications scenarios. We show that it is
already possible to make significant progress even by using only the present
samples. The important role of selection effects is discussed. For instance we
show that the multiple flux selections typical of available surveys could
induce some of the correlations found in color-color diagrams. These latter
results should apply to any study of flux limited samples.

</DOC>
<DOC>
<DOCNO> 152518 </DOCNO>
Closed strings from nothing


  We study the physics of open strings in bosonic and type II string theories
in the presence of unstable D-branes. When the potential energy of the open
string tachyon is at its minimum, Sen has argued that only closed strings
remain in the perturbative spectrum. We explore the scenario of Yi and of
Bergman, Hori and Yi, who argue that the open string degrees of freedom are
strongly coupled and disappear through confinement. We discuss arguments using
open string field theory and worldsheet boundary RG flows, which seem to
indicate otherwise. We then describe a solitonic excitation of the open string
tachyon and gauge field with the charge and tension of a fundamental closed
string. This requires a double scaling limit where the tachyon is taken to its
minimal value and the electric field is taken to its maximum value. The
resulting flux tube has an unconstrained spatial profile; and for large
fundamental string charge, it appears to have light, weakly coupled open
strings living in the core. We argue that the flux tube acquires a size or
order $\alpha'$ through sigma model and string coupling effects; and we argue
that confinement effects make the light degrees of freedom heavy and strongly
interacting.

</DOC>
<DOC>
<DOCNO> 69098 </DOCNO>
Gauge-Independent W-Boson Partial Decay Widths


  We calculate the partial decay widths of the W boson at one loop in the
standard model using the on-shell renormalization scheme endowed with a
gauge-independent definition of the Cabibbo-Kobayashi-Maskawa (CKM) mixing
matrix. We work in $R_\xi$ gauge and explicitly verify that the final
expressions are independent of the gauge parameters. Furthermore, we establish
the relationship between the on-shell and $\bar{\mathrm{MS}}$ definitions of
the CKM matrix, both in its generic form and in the Wolfenstein
parameterization. As a by-product of our analysis, we recover the beta function
of the CKM matrix.

</DOC>
<DOC>
<DOCNO> 71072 </DOCNO>
B and D Mesons in Lattice QCD


  Computational and theoretical developments in lattice QCD calculations of B
and D mesons are surveyed. Several topical examples are given: new ideas for
calculating the HQET parameters \bar{\Lambda} and \lambda_1; form factors
needed to determine |V_{cb}| and |V_{ub}|; bag parameters for the mass
differences of the B mesons; and decay constants. Prospects for removing the
quenched approximation are discussed.

</DOC>
<DOC>
<DOCNO> 9121 </DOCNO>
Dynamic critical exponent of two-, three-, and four-dimensional XY


  The dynamic critical exponent $z$ is determined numerically for the
$d$-dimensional XY model ($d=2, 3$, and 4) subject to relaxational dynamics and
resistively shunted junction dynamics. We investigate both the equilibrium
fluctuation and the relaxation behavior from nonequilibrium towards
equilibrium, using the finite-size scaling method. The resulting values of $z$
are shown to depend on the boundary conditions used, the periodic boundary
condition, and fluctuating twist boundary condition (FTBC), which implies that
the different treatments of the boundary in some cases give rise to different
critical dynamics. It is also found that the equilibrium scaling and the
approach to equilibrium scaling for the the same boundary condition do not
always give the same value of $z$. The FTBC in conjunction with the finite-size
scaling of the linear resistance for both type of dynamics yields values of $z$
consistent with expectations for superfluids and superconductors: $z = 2$, 3/2,
and 2 for $d=2$, 3, and 4, respectively.

</DOC>
<DOC>
<DOCNO> 151729 </DOCNO>
Measure Fields, The Cosmological Constant and Scale Invariance


  The consequences of considering the measure of integration in the action to
be defined by degrees of freedom independent of the metric are studied. Models
without the cosmological constant problem, new ways of spontaneously breaking
scale symmetry which have an interesting cosmology and theories of extended
objects (string, branes) without a fundamental scale appear possible.

</DOC>
<DOC>
<DOCNO> 13558 </DOCNO>
Influence of spin fluctuations on the superconducting transition


  Spin fluctuations enter the calculation of the superconducting transition
temperature T$_c$ only in the next-to-leading order (i.e., in O(1/N$^2$) of the
1/N expansion of the t-J model. We have calculated these terms and show that
they have only little influence on the value of T$_c$ obtained in the leading
order O(1/N) in the optimal and overdoped region, i.e., for dopings larger than
the instability towards a flux phase. This result disagrees with recent
spin-fluctuation mediated pairing theories. The discrepancies can be traced
back to the fact that in our case the coupling between electrons and spins is
determined by the t-J model and not adjusted and that the spin susceptibility
is rather broad and structureless and not strongly peaked at low energies as in
spin-fluctuation models. Relating T$_c$ and transport we show that the
effective interactions in the particle-particle and particle-hole channels are
not simply related within the 1/N expansion by different Fermi surface averages
of the same interactin as in the case of phonons or spin fluctuations. As a
result, we find that large values for T$_c$ and rather small scattering rates
in the normal state as found in the experiments can easily be reconciled with
each other. We also show that correlation effects heavily suppress transport
relaxation rates relative to quasiparticle relaxation rates in the case of
phonons but not in the case of spin fluctuations.

</DOC>
<DOC>
<DOCNO> 11006 </DOCNO>
The effect of disorder on the critical temperature of a dilute hard


  We have performed Path Integral Monte Carlo (PIMC) calculations to determine
the effect of quenched disorder on the superfluid density of a dilute 3D hard
sphere gas. The disorder was introduced by locating set of hard cylinders
randomly inside the simulation cell. Our results indicate that the disorder
leaves the superfluid critical temperature basically unchanged. Comparison to
experiments of helium in Vycor is made.

</DOC>
<DOC>
<DOCNO> 169584 </DOCNO>
Quantum nonlinear lattices and coherent state vectors


  Quantized nonlinear lattice models are considered for two different classes,
boson and fermionic ones. The quantum discrete nonlinear Schroedinger model
(DNLS) is our main objective, but its so called modified discrete nonlinear
(MDNLS) version is also included, together with the fermionic polaron (FP)
model. Based on the respective dynamical symmetries of the models, a method is
put forward which by use of the associated boson and spin coherent state
vectors (CSV) and a factorization ansatz for the solution of the Schroedinger
equation, leads to quasiclassical Hamiltonian equations of motion for the CSV
parameters. Analysing the geometrical content of the factorization ansatz made
for the state vectors invokes the study of the Riemannian and symplectic
geometry of the CSV manifolds as generalized phase spaces. Next, we investigate
analytically and numerically the behavior of mean values and uncertainties of
some physically interesting observables as well as the modifications in the
quantum regime of processes such as the discrete self trapping (DST), in terms
of the Q-function and the distribution of excitation quanta of the lattice
sites. Quantum DST in the symmetric ordering of lattice operators is found to
be relatively enhanced with respect to the classical DST. Finally, the meaning
of the factorization ansatz for the lattice wave function is explained in terms
of disregarded quantum correlations, and as a quantitative figure of merit for
that ansatz a correlation index is introduced.

</DOC>
<DOC>
<DOCNO> 151143 </DOCNO>
Two Two-Dimensional Supergravity Theories from Calabi-Yau Four-Folds


  We consider two-dimensional supergravity theories with four supercharges
constructed from compactification of Type II string theory on a generic
Calabi-Yau four-fold. In Type IIA and Type IIB cases, respectively, new
superspace formulations of N=(2,2) and N=(0,4) dilaton supergravities are found
and their coupling to matter multiplets is discussed.

</DOC>
<DOC>
<DOCNO> 118150 </DOCNO>
The role of the outer boundary condition in accretion disk models:


  The influence of the outer boundary condition (OBC) on the dynamics and
radiation of optically thin accretion flow is investigated. Bremsstrahlung and
synchrotron radiations amplified by Comptonization are taken into account and
two-temperature plasma assumption is adopted. The three OBCs we adopted are the
temperatures of the electrons and ions and the specific angular momentum of the
accretion flow at a certain outer boundary. We find that when the general
parameters such as the mass accretion rate and the viscous parameter are fixed,
the peak flux at various bands such as radio, IR and X-ray, can differ by as
large as several orders of magnitude under different OBCs in our example. Our
results indicate that OBC is both dynamically and radiatively important
therefore should be regarded as a new ``parameter'' in accretion disk models.
We apply the above results to the compact radio source Sgr A* and find that the
discrepancy between the mass accretion rate favored by ADAF models in the
literature and that favored by the three dimensional hydrodynamical simulation
can be naturally resolved by seriously considering the outer boundary condition
of the accretion flow.

</DOC>
<DOC>
<DOCNO> 170612 </DOCNO>
Comment on ``Manipulating the frequency entangled states by an


  A recent theoretical paper [1] proposes a scheme for entanglement swapping
utilizing acousto-optic modulators without requiring a Bell-state measurement.
In this comment, we show that the proposal is flawed and no entanglement
swapping can occur without measurement.

</DOC>
<DOC>
<DOCNO> 71127 </DOCNO>
QCD string in mesons and baryons


  Field distributions generated by static quark-antiquark and QQQ sources are
calculated analytically in the framework of Gaussian (bilocal) approximation of
Field Correlator Method (FCM). Special attention is paid to the QQQ system and
asymmetric configurations are also studied. In both quark-antiquark and QQQ
cases the string consists mainly of longitudinal color electric field.
Transverse color electric field contribution is shown to be less then 3%.
Baryon string has an Y-like shape with a deep well at the string junction
position. Field distributions for quark-diquark and for three quarks on one
line are considered. The interaction potential for quarks forming an
equilateral triangle is calculated. The material of the paper is illustrated by
24 3D colored pictures.

</DOC>
<DOC>
<DOCNO> 11363 </DOCNO>
Exclusion of quantum coherence as the origin of the 2D metallic state in


  The temperature and density dependence of the phase coherence time
$\tau_\phi$ in high-mobility silicon inversion layers was determined from the
magnetoresistivity due to weak localization. The upper temperature limit for
single-electron quantum interference effects was delineated by comparing
$\tau_\phi$ with the momentum relaxation time $\tau$. A comparison between the
density dependence of the borders for quantum interference effects and the
strong resistivity drop reveals that theses effects are not related to each
other. As the strong resistivity drop occurs in the Drude regime, the apparent
metallic behavior can not be caused by quantum coherent effects.

</DOC>
<DOC>
<DOCNO> 13973 </DOCNO>
Interface magnetic anisotropy in cobalt clusters embedded in a platinum


  A low concentration of cobalt clusters with a fcc structure and containing
almost one thousand atoms are embedded in two different metallic matrices:
platinum and niobium. Samples have been prepared using a co-deposition
technique. Cobalt clusters preformed in the gas phase and matrix atoms are
simultaneously deposited on a silicon substrate under Ultra High Vacuum
conditions. This original technique allows to prepare nanostructured systems
from miscible elements such as Co/Pt and Co/Nb in which clusters keep a pure
cobalt core surrounded with an alloyed interface. Magnetic measurements
performed using a Vibrating Sample Magnetometer (VSM) reveal large differences
in the magnetic properties of cobalt clusters in Pt and Nb pointing out the key
role of cluster/matrix interfaces.

</DOC>
<DOC>
<DOCNO> 117291 </DOCNO>
Geomagnetic control of the spectrum of traveling ionospheric


  In this paper an attempt is made to verify the hypothesis on the role of
geomagnetic disturbances as a factor determining the intensity of traveling
ionospheric disturbances (TIDs). To improve the statistical validity of the
data, we have used the based on the new GLOBDET technology method involving a
global spatial averaging of disturbance spectra of the total electron content
(TEC). To characterize the TID intensity quantitatively, we suggest that a new
global index of the degree of disturbance should be used, which is equal to the
mean value of the rms variations in TEC within the selected range of spectral
periods (of 20-60 min in the present case). It was found that power spectra of
daytime TEC variations in the range of 20-60 min periods under quiet conditions
have a power-law form, with the slope index k = -2.5. With an increase of the
level of magnetic disturbance, there is an increase in total intensity of TIDs,
with a concurrent kink of the spectrum caused by an increase in oscillation
intensity in the range of 20-60 min. It was found that an increase in the level
of geomagnetic activity is accompanied by an increase in total intensity of
TEC; however, it correlates not with the absolute level of Dst, but with the
value of the time derivative of Dst (a maximum correlation coefficient reaches
-0.94). The delay of the TID response of the order of 2 hours is consistent
with the view that TIDs are generated in auroral regions, and propagate
equatorward with the velocity of about 300-400 m/s.

</DOC>
<DOC>
<DOCNO> 40495 </DOCNO>
SUSY Searches at Tevatron Collider


  This article presents recent results of searches for Supersymmetry using the
CDF and the D$\not$O detector at the Fermilab Tevatron Collider. Described are
the Tevatron searches for third generation scalar quarks and for supersymmetric
signatures involving photons. All the reported results have been obtained
assuming theoretical models in which $\mathcal{R}$-parity is conserved.

</DOC>
<DOC>
<DOCNO> 70058 </DOCNO>
Probing chiral symmetry of nucleon by threshold $\eta \pi$ production


  Double meson production of the eta and pion at the threshold region is
investigated in order to determine chiral property of the nucleon.
 The eta can be used as a probe for the negative parity nucleon $N^* \equiv
N^*(1535)$ produced in the intermediate state.
 The coupling of the low energy pion in the final state is then used to extract
the sign of the Yukawa coupling, $\gpRR$, which distinguishes the two
realizations of chiral symmetry, either naive or mirror, for the nucleon.

</DOC>
<DOC>
<DOCNO> 123285 </DOCNO>
Testing Hydrodynamic Models of LMC X-4 with UV and X-ray Spectra


  We compare the predictions of hydrodynamic models of the LMC X-4 X-ray binary
system with observations of UV P Cygni lines with the GHRS and STIS
spectrographs on the Hubble Space Telescope. The hydrodynamic model determines
density and velocity fields of the stellar wind, wind-compressed disk,
accretion stream, Keplerian accretion disk, and accretion disk wind. We use a
Monte Carlo code to determine the UV P Cygni line profiles by simulating the
radiative transfer of UV photons that originate on the star and are scattered
in the wind. The qualitative orbital variation predicted is similar to that
observed, although the model fails to reproduce the strong orbital asymmetry
(the observed absorption is strongest for phi>0.5). The model predicts a
mid-eclipse X-ray spectrum, due almost entirely to Compton scattering, with a
factor 4 less flux than observed with ASCA. We discuss how the model may need
to be altered to explain the spectral variability of the system.

</DOC>
<DOC>
<DOCNO> 102790 </DOCNO>
Invitation to higher local fields, Part II, section 6: Phi-Gamma-modules


  This is is a survey of applications of Fontaine's theory of p-adic
representations of local fields (Phi-Gamma-modules) to Galois cohomology of
local fields and explicit formulas for the Hilbert symbol in relation with
two-dimensional local objects.

</DOC>
<DOC>
<DOCNO> 151291 </DOCNO>
Superextendons with a modified measure


  For superstrings, the consequences of replacing the measure of integration
$\sqrt{-\gamma}d^2 x$ in the Polyakov's action by $\Phi d^2 x$ where $\Phi$ is
a density built out of degrees of freedom independent of the metric
$\gamma_{ab}$ defined in the string are studied. As in Siegel reformulation of
the Green Schwarz formalism the Wess-Zumino term is the square of
supersymmetric currents. As opposed to the Siegel case, the compensating fields
needed for this do not enter into the action just as in a total derivative.
They instead play a crucial role to make up a consistent dynamics. The string
tension appears as an integration constant of the equations of motion. The
generalization to higher dimensional extended objects is also studied using in
this case the Bergshoeff and Sezgin formalism with the associated additional
fields, which again are dynamically relevant unlike the standard formulation.
Also unlike the standard formulation, there is no need of a cosmological term
on the world brane.

</DOC>
<DOC>
<DOCNO> 102618 </DOCNO>
The Whitehead group of the Novikov ring


  The Bass-Heller-Swan-Farrell-Hsiang-Siebenmann decomposition of the Whitehead
group $K_1(A_{\rho}[z,z^{-1}])$ of a twisted Laurent polynomial extension
$A_{\rho}[z,z^{-1}]$ of a ring $A$ is generalized to a decomposition of the
Whitehead group $K_1(A_{\rho}((z)))$ of a twisted Novikov ring of power series
$A_{\rho}((z))=A_{\rho}[[z]][z^{-1}]$. The decomposition involves a summand
$W_1(A,\rho)$ which is an abelian quotient of the multiplicative group
$W(A,\rho)$ of Witt vectors $1+a_1z+a_2z^2+... \in A_{\rho}[[z]]$. An example
is constructed to show that in general the natural surjection $W(A,\rho)^{ab}
\to W_1(A,\rho)$ is not an isomorphism.

</DOC>
<DOC>
<DOCNO> 117883 </DOCNO>
Performance Results of the AMS-01 Aerogel Threshold Cherenkov


  The Alpha Magnetic Spectrometer (AMS) was flown in june 1998 on board of the
space shuttle Discovery (flight STS-91) at an altitude ranging between 320 and
390 km. This preliminary version of AMS included an Aerogel Threshold Cherenkov
detector (ATC) to separate antiprotons from electron background, for momenta
less than 3.5 GeV/c. In this paper, the design and physical principles of ATC
will be discussed briefly, then the performance results of the ATC will be
presented.

</DOC>
<DOC>
<DOCNO> 99362 </DOCNO>
Drawing with Complex Numbers


  It is not commonly realized that the algebra of complex numbers can be used
in an elegant way to represent the images of ordinary 3-dimensional figures,
orthographically projected to the plane. We describe these ideas here, both
using simple geometry and setting them in a broader context.

</DOC>
<DOC>
<DOCNO> 151591 </DOCNO>
Anomalous D-Brane Charge in F-Theory Compactifications


  Tadpole cancellation in F-theory on an elliptic Calabi-Yau fourfold $X\to
B_3$ demands some spacetime-filling three-branes (points in $B_3$). If moved to
the discriminant surface, which supports the gauge group, and dissolved into a
finite size instanton, the second Chern class of the corresponding bundle $E$
is expected to give a compensating contribution. However the dependence of
D-brane charge on the geometry of $W$ and on the embedding $i: W\to B_3$ gives
a correction to $c_2(E)$. We show how this is reconciled by considering the
torsion sheaf $i_*E$ and discuss some integrality issues related to global
properties of $X$ as well as the moduli space of this object.

</DOC>
<DOC>
<DOCNO> 40648 </DOCNO>
Search for CP Violation in $D^{0}\to K_{S}^{0}\pi^{0}$, $D^{0}\to


  We have searched for CP-violating asymmetries in neutral charm meson decays
in 13.7 fb^-1 of e^+e^- collision data at sqrt{s} = 10.6 GeV with the CLEO
detector. The measured asymmetries in the rate of D0 and D0bar decays to
K0sPi0, Pi0Pi0 and K0sK0s final states are (+0.1 +- 1.3)%, (+0.1 +- 4.8)% and
(-23 +- 19)%, respectively.

</DOC>
<DOC>
<DOCNO> 170028 </DOCNO>
Functional Approach to Quantum Decoherence and the Classical Final Limit


  For a wide set of quantum systems it is demonstrated that the quantum regime
can be considered as the transient phase while the final classical statistical
regime is a permanent state. A basis where exact matrix decoherence appears for
these final states is found. The relation with the decoherence of histories
formalism is studied. A set of final intrinsically consistent histories is
found.

</DOC>
<DOC>
<DOCNO> 69698 </DOCNO>
On classical description of radiation from neutral fermion with


  Electromagnetic radiation from an uncharged spin 1/2 particle with an
anomalous magnetic moment moving in the classical electromagnetic external
field originates from quantum spin-flip transitions. Although this process has
a purely quantum nature, it was observed for certain particular external field
configurations that, when quantum recoil is neglected, the radiation power
corresponds to the classical radiation from an evolving magnetic dipole. We
argue that this correspondence has a more general validity in the case of an
unpolarized particle and derive a general formula for radiation in terms of the
external field strength and its derivatives. A classical dynamics of the spin
is described by the Bargmann-Michel-Telegdi equation.

</DOC>
<DOC>
<DOCNO> 119234 </DOCNO>
Modeling a high mass turn down in the stellar initial mass function


  Statistical sampling from the stellar initial mass function (IMF) for all
star-forming regions in the Galaxy would lead to the prediction of ~1000 Msun
stars unless there is a rapid turn-down in the IMF beyond several hundred solar
masses. Such a turndown is not necessary for dense clusters because the number
of stars sampled is always too small. Here we explore several mechanisms for an
upper mass cutoff, including an exponential decline of the star formation
probability after a turbulent crossing time. The results are in good agreement
with the observed IMF over the entire stellar mass range, and they give a
gradual turn down compared to the Salpeter function above ~100 Msun for normal
thermal Jeans mass, M_J. The upper mass turn down should scale with M_J in
different environments. A problem with the models is that they cannot give both
the observed power-law IMF out to the high-mass sampling limit in dense
clusters, as well as the observed lack of supermassive stars in whole galaxy
disks. Either there is a sharper upper-mass cutoff in the IMF, perhaps from
self-limitation, or the IMF is different for dense clusters than for the
majority of star formation that occurs at lower density. Dense clusters seem to
have an overabundance of massive stars relative to the average IMF in a galaxy.

</DOC>
<DOC>
<DOCNO> 71002 </DOCNO>
On the microscopic dynamics of DCC formation


  The dynamics of the pion field after a quench is studied in the framework of
the linear sigma model. Our aim is to determine to what extent the amplified
pion field resembles the DCC picture originally proposed in the early '90s. We
present the result of a computer experiment where, among other things, we study
in detail the correlation between isospin orientations of the distinct modes of
the field. We show that this correlation is absent. In a sense, the distinct
modes behave as distinct DCCs. The implications of this observation are
discussed.

</DOC>
<DOC>
<DOCNO> 119044 </DOCNO>
Photon Propagation Around Compact Objects and the Inferred Properties of


  Anomalous X-ray pulsars, compact non-pulsing X-ray sources in supernova
remnants, and X-ray bursters are three distinct types of sources for which
there are viable models that attribute their X-ray emission to thermal emission
from the surface of a neutron star. Inferring the surface area of the emitting
regions in such systems is crucial in assessing the viability of different
models and in providing bounds on the radii of neutron stars. We show that the
inferred areas of the emitting regions may be over- or under-estimated by a
factor of <=2, because of the geometry of the system and general relativistic
light deflection, combined with the effects of phase averaging. Such effects
make the determination of neutron-star radii uncertain, especially when
compared to the ~5% level required for constraining the equation of state of
neutron-star matter. We also note that, for a given spectral shape, the
inferred source luminosities and pulse fractions are anticorrelated because
they depend on the same properties of the emitting regions, namely their sizes
and orientations, i.e., brighter sources have on average weaker pulsation
amplitudes than fainter sources. We argue that this property can be used as a
diagnostic tool in distinguishing between different spectral models. As an
example, we show that the high inferred pulse fraction and brightness of the
pulsar RXS J1708-40 are inconsistent with isotropic thermal emission from a
neutron-star surface. Finally, we discuss the implication of our results for
surveys in the soft X-rays for young, cooling neutron stars in supernova
remnants and show that the absence of detectable pulsations from the compact
source at the center of Cas A (at a level of >=30%) is not a strong argument
againts its identification with a spinning neutron star.

</DOC>
<DOC>
<DOCNO> 118238 </DOCNO>
Lyman-alpha Imaging of a Very Luminous z=2.3 Starburst Galaxy with WFPC2


  We investigate a very luminous Lyman-alpha emitting galaxy, associated with a
z=2.3 damped absorption system in the spectrum of the QSO PHL 957. The galaxy
was observed with the HST WFPC2, through a narrow filter (F410M) corresponding
to rest-frame Lyman -alpha, for 41.2 ksec, with shorter exposures in F555W and
F814W. The galaxy is resolved into a close (0.35 arcsec) pair of two
components, CFgA and CFgB. The profile of CFgA is consistent with an
exponential disk, but CFgB is closer to a bulge galaxy. Fr om the observed
colours we estimate rest-frame Lyman-alpha equivalent widths of 151 Angstroms
for CFgA and 33 for CFgB. From the F814W and F555W magnitudes we estimate
rest-frame blue-band absolute magnitudes of -23.12 for CFgA and -23.24 for
CFgB, signi ficantly brighter than local galaxies of the same size. CFgA shows
a remarkable 3.9 magnitudes of surface brightness enhancement relative to local
spirals, and we speculate that this may be the result of a very luminous
starburst, triggered by the merger of the two components. The Lyman-alpha
emission could be from a brief phase early in the starburst in which most of
these photons can escape.
         We search for other z=2.3 galaxies with strong Lyman-alpha emission,
selecting these by a colour F410M-F555W<-0.2. Eight candidate sources, all
fainter than CFgA, are identified. One is a point-source and may be an AGN; the
others are irregular a nd of low surface brightness, appearing typical of Lyman
break galaxies, but with Lyman-alpha equivalent widths near 100 Angstroms.

</DOC>
<DOC>
<DOCNO> 12931 </DOCNO>
Statistical physics of adaptive correlation of agents in a market


  Recent results and interpretations are presented for the thermal minority
game, concentrating on deriving and justifying the fundamental stochastic
differential equation for the microdynamics.

</DOC>
<DOC>
<DOCNO> 120799 </DOCNO>
Correcting Parameters of Events Based on the Entropy of Microlensing


  We entertain the idea that robust theoretical expectations can become a tool
in removing hidden observational or data-reduction biases. We illustrate this
approach for a specific problem associated with gravitational microlensing.
Using the fact that a group is more than just a collection of individuals, we
derive formulae for correcting the distribution of the dimensionless impact
parameters of events, u_min. We refer to the case when undetected biases in the
u_min distribution can be alleviated by multiplication of impact parameters of
all events by a common constant factor. We show that in this case the general
maximum likelihood problem of solving an infinite number of equations reduces
to two constraints, and we find an analytic solution. Under the above
assumptions, this solution represents a state in which the ``entropy'' of a
microlensing ensemble is at its maximum, that is, the distribution of u_min
resembles a specific, theoretically expected, box-like distribution to the
highest possible extent. We also show that this technique does not allow one to
correct the parameters of individual events on the event by event basis
independently from each other.

</DOC>
<DOC>
<DOCNO> 84439 </DOCNO>
Conformal positive mass theorems


  We show the following two extensions of the standard positive mass theorem
(one for either sign): Let (N,g) and (N,g') be asymptotically flat Riemannian
3-manifolds with compact interior and finite mass, such that g and g' are twice
Hoelder differentiable and related via the conformal rescaling g' = (phi^4).g,
with a twice Hoelder differentiable function phi>0. Assume further that the
corresponding Ricci scalars satisfy either R + (phi^4).R' >= 0 or R -
(phi^4).R' >= 0. Then the corresponding masses satisfy m + m' >= 0 or m - m' >=
0, respectively. Moreover, in the case of the minus signs, equality holds iff g
and g' are isometric, whereas for the plus signs equality holds iff both (N,g)
and (N,g') are flat Euclidean spaces.
  While the proof of the case with the minus signs is rather obvious, the case
with the plus signs requires a subtle extension of Witten's proof of the
standard positive mass theorem. The idea for this extension is due to
Masood-ul-Alam who, in the course of an application, proved the rigidity part m
+ m' = 0 of this theorem, for a special conformal factor. We observe that
Masood-ul-Alam's method extends to the general situation.

</DOC>
<DOC>
<DOCNO> 69224 </DOCNO>
GENIUS project, neutrino oscillations and Cosmology: neutrinos reveal


  The neutrinoless double beta decay as well as any other laboratory experiment
has not been able to answer the question of the neutrino's nature. Hints on the
answer are available when neutrino oscillations and $(\beta\beta)_{0 \nu}$ are
considered simultaneously. In this case phenomenologically interesting neutrino
mass schemes can lead to non-vanishing and large values of $<m_{\nu}>$. As a
consequence, some schemes with Majorana neutrinos can be ruled out even now. If
we assume that in addition neutrinos contribute to Hot Dark Matter then the
window for Majorana neutrinos is even more restricted, e.g. GENIUS experiment
will be sensitive to scenarios with three Majorana neutrinos.

</DOC>
<DOC>
<DOCNO> 117552 </DOCNO>
A Novel Supernova Detector


  We discuss the prospects for detecting nu_{mu,tau} and nu_{tau}neutrinos from
Type II supernovas using the novel detector at the Supernova Burst Observatory
(SNBO) or OMNIS that is being designed for an underground laboratory in the
USA. This detector would collect ~2000 flavor selected events from a Galactic
supernova and could probe neutrino mass down to a few eV, as well as the
dynamics of the supernova process. We believe this is essential to further our
understanding of the neutrino section of elementary particle physics.

</DOC>
<DOC>
<DOCNO> 120835 </DOCNO>
The Size Distribution of the Kuiper Belt Objects


  The size distribution is determined directly from the current known Kuiper
Belt Objects (KBOs). We found that there is a peak for the size distribution
around 230 km in diameter. For the objects larger than 230 km, the KBOs
populate as $N(s) \propto s^{-4}$ as we see in Jewitt et al. (1998). For the
objects smaller than 230 km, we found $N(s) \propto s^{3}$. This result from
the current observational data is new and very different from the conventional
concept of the KBO size distribution. Though the true size distribution might
change from what we have after more KBOs be discovered, we argue that the
existence of a peak around 150 km to 250 km is likely.

</DOC>
<DOC>
<DOCNO> 71807 </DOCNO>
Systematics of Large Axial Vector Meson Production in Heavy Flavor Weak


  Branching ratios observed for $D$ and B decays to final states
$a_1(1260)^{\pm} X$ are comparable to those for corresponding decays to
$\pi^{\pm} X$ and $\rho^{\pm} X$ and much larger than those for all other
decays. Implications are discussed of a "vector-dominance model" in which a $W$
is produced and immediately turns into an axial vector, vector or pseudoscalar
meson. Data for decays to all such final states are shown to have large
branching ratios and satisfy universality relations. Upper limits on small
strong phase differences between amplitudes relevant to CP violation models are
obtained from analysis of the predicted and observed suppression of $B^o$
decays into neutral final states $\pi^o X^o$, $\rho^oX^o$ and $a_1^o X^o$. .
Branching ratios of $\approx 1%$ are predicted for the as yet unobserved
presence of the $D_{s1}(2536)$ charmed-strange axial vector in B decays.

</DOC>
<DOC>
<DOCNO> 122359 </DOCNO>
The Discovery of an Outburst and Pulsed X-ray Flux from SMC X-2 from


  Rossi X-ray Timing Explorer All Sky Monitor observations of SMC X-2 show that
the source experienced an outburst in January to April 2000 reaching a peak
luminosity of greater than ~10^38 ergs s^-1. RXTE Proportional Counter Array
observations during this outburst reveal the presence of pulsations with a
2.37s period. However, optical photometry of the optical counterpart showed the
source to be still significantly fainter than it was more than half a year
after the outburst in the 1970s when SMC X-2 was discovered.

</DOC>
<DOC>
<DOCNO> 85363 </DOCNO>
Casimir Effect for Spherical Shell in de Sitter Space


  The Casimir stress on a spherical shell in de Sitter background for massless
scalar field satisfying Dirichlet boundary conditions on the shell is
calculated. The metric is written in conformally flat form. Although the metric
is time dependent no particles are created. The Casimir stress is calculated
for inside and outside of the shell with different backgrounds corresponding to
different cosmological constants. The detail dynamics of the bubble depends on
different parameter of the model. Specifically, bubbles with true vacuum inside
expand if the difference in the vacuum energies is small, otherwise they
collapse.

</DOC>
<DOC>
<DOCNO> 84649 </DOCNO>
de Broglie oscillation, rest mass and inertia


  The model of a relativistic free massive point particle is investigated in
the context of a Hamiltonian constraint system. It is shown that de Broglie
oscillation, rest mass and inertia may be described within this model of
Hamiltonian constraint system.

</DOC>
<DOC>
<DOCNO> 9259 </DOCNO>
Cooper pair dispersion relation for weak to strong coupling


  Cooper pairing in two dimensions is analyzed with a set of renormalized
equations to determine its binding energy for any fermion number density and
all coupling assuming a generic pairwise residual interfermion interaction. \
Also considered are Cooper pairs (CPs) with nonzero center-of-mass momentum
(CMM)---usually neglected in BCS theory---and their binding energy is expanded
analytically in powers of the CMM up to quadratic terms. \ A
Fermi-sea-dependent {\it linear} term in the CMM dominates the pair excitation
energy in weak coupling (also called the BCS regime) while the more familiar
quadratic term prevails in strong coupling (the Bose regime). The crossover,
though strictly unrelated to BCS theory {\it per se,} is studied numerically as
it is expected to play a central role in a model of superconductivity as a
Bose-Einstein condensation of CPs where the transition temperature vanishes for
all dimensionality $d\leq 2$ for quadratic dispersion, but is {\it nonzero }
for all $d\geq 1$ for linear dispersion.

</DOC>
<DOC>
<DOCNO> 170393 </DOCNO>
Interpreting the time of decay measurement: phenomenological


  We point out that the spreading of wave packets could be significant in
affecting the analysis of experiments involving the measurement of time of
decay. In particular, we discuss a hitherto unexplored application of the Bohm
model in properly taking into account the nontrivial effect of wave packet
spreading in the CP violation experiment.

</DOC>
<DOC>
<DOCNO> 120991 </DOCNO>
Discovery of a New Supernova Remnant in the Direction of G69.7+1.0


  We discovered a middle-aged supernova remnant (SNR) in the vicinity of
G69.7+1.0 using the ASCA satellite. G69.7+1.0 was identified in the 2.7 GHz
survey and classified as a shell-type SNR with a diameter of 16 arcmin. During
the ROSAT all-sky survey, the X-ray emission was detected in the direction of
G69.7+1.0. However, it extends beyond the radio shell, and an X-ray bright
region was located outside of the radio shell. A spectral study with the ASCA
and ROSAT shows a thin thermal plasma with an electron temperature of ~0.4 keV.
There is no significant variation of the spectral parameters over the field of
view, except for the lower column density of the eastern part. We also found a
large shell structure which surrounds the X-ray bright region in both optical
and radio images. We suggest that the observed X-ray emission is associated
with the large optical and radio shell, and that they are part of a new SNR,
different from the radio SNR G69.7+1.0, which we have named AX J2001+3235 or
G69.4+1.2. The large shell and the electron temperature of ~0.4 keV indicate
that AX J2001+3235 is an evolved SNR. From a comparison with the column density
of CTB 80 (G69.0+2.7), we estimate that the distance of the SNR is about 2.5
kpc.

</DOC>
<DOC>
<DOCNO> 178420 </DOCNO>
Exploring vector meson masses in nuclear collisions


  The formalism developed earlier by us for the propagation of a resonance in
the nuclear medium in proton-nucleus collisions has been modified to the case
of vector boson production in heavy-ion collisions. The first part of the talk
describes this formalism. The formalism includes coherently the contribution to
the observed di-lepton production from the decay of a vector boson inside as
well as outside the nuclear medium. The calculated invariant rho mass
distributions are presented for the $\rho $-meson production using optical
potentials estimated within the VDM and the resonance model.
  In the second part of the talk we write a formalism for coherent rho
production in proton nucleus collisions and explore the sensitivity of the
(p,p$^\prime \rho ^0$) reaction cross section to medium mass modification of
the rho meson.

</DOC>
<DOC>
<DOCNO> 100261 </DOCNO>
e to the A, in a New Way, Some More to Say


  Expressions are given for the exponential of a hermitian matrix, A. Replacing
A by iA these are explicit formulas for the Fourier transform of exp(iA). They
extend to any size matrix the previous results for the 2 X 2, 3 X 3, and 4 X 4
cases. The expressions are elegant and should prove useful.

</DOC>
<DOC>
<DOCNO> 8953 </DOCNO>
On the Energy Minima of the SK Model


  We study properties of the energy minima obtained by quenching equilibrium
configurations of the Sherrington-Kirkpatrick (SK) mean field spin glass. We
measure the probability distribution of the overlap among quenched
configurations and the quenched energy, looking at the dependence on the
starting equilibrium temperature, and performing a systematic analysis of
finite size effects.

</DOC>
<DOC>
<DOCNO> 11456 </DOCNO>
Correlated quantum measurement of a solid-state qubit


  We propose a solid-state experiment to study the process of continuous
quantum measurement of a qubit state. The experiment would verify that an
individual qubit stays coherent during the process of measurement (in contrast
to the gradual decoherence of the ensemble-averaged density matrix) thus
confirming the possibility of the qubit purification by continuous measurement.
The experiment can be realized using quantum dots, single-electron transistors,
or SQUIDs.

</DOC>
<DOC>
<DOCNO> 13518 </DOCNO>
Spectral properties of a narrow-band Anderson model


  We consider single-particle spectra of a symmetric narrow-band Anderson
impurity model, where the host bandwidth $D$ is small compared to the
hybridization strength $\Delta_{0}$. Simple 2nd order perturbation theory (2PT)
in $U$ is found to produce a rich spectral structure, that leads to rather good
agreement with extant Lanczos results and offers a transparent picture of the
underlying physics. It also leads naturally to two distinct regimes of spectral
behaviour, $\Delta_{0}Z/D\gg 1 $ and $\ll 1$ (with $Z$ the quasi-particle
weight), whose existence and essential characteristics are discussed and shown
to be independent of 2PT itself. The self-energy $\Sigma_{i\omega}$ is also
examined beyond the confines of PT. It is argued that on frequency scales of
order $\omega\sim\sqrt{Delta_{0}D}$, the self-energy in {\em strong} coupling
is given precisely by the 2PT result, and we point out that the resultant poles
in $\Sigma_{i\omega}$ connect continuously to that characteristic of the atomic
limit. This in turn offers a natural rationale for the known inability of the
skeleton expansion to capture such behaviour, and points to the intrinsic
dangers of partial infinite-order summations that are based on PT in $U$.

</DOC>
<DOC>
<DOCNO> 116630 </DOCNO>
Modulation Instability and Pattern Formation in Spatially Incoherent


  We present the first experimental observation of modulation instability of
partially spatially incoherent light beams in non-instantaneous nonlinear
media. We show that even in such a nonlinear partially coherent system (of
weakly-correlated particles) patterns can form spontaneously. Incoherent MI
occurs above a specific threshold that depends on the beams' coherence
properties (correlation distance), and leads to a periodic train of
one-dimensional (1D) filaments. At a higher value of nonlinearity, incoherent
MI displays a two-dimensional (2D) instability and leads to self-ordered arrays
of light spots.

</DOC>
<DOC>
<DOCNO> 119406 </DOCNO>
ISO observations of a sample of Compact Steep Spectrum and GHz Peaked


  We present results from observations obtained with ISOPHOT, on board the ISO
satellite, of a representative sample of seventeen CSS/GPS radio galaxies and
of a control sample of sixteen extended radio galaxies spanning similar ranges
in redshift (0.2 <= z <= 0.8) and radio luminosity (P_2.7 GHz >= 10^26 W/Hz).
The observations have been performed at lambda = 60, 90, 174 and 200 microns.
Seven of the CSS/GPS sources have detections >= 3 sigma at one or more
wavelengths, one of which is detected at >= 5 sigma. By co-adding the data we
have obtained average flux densities at the four wavelengths. We found no
evidence that the FIR luminosities of the CSS/GPS sources are significantly
different from those of the extended objects and therefore there is not any
support for CSS/GPS sources being objects "frustrated" by an abnormally dense
ambient medium. The two samples were then combined, providing FIR information
on a new sample of radio galaxies at intermediate redshifts. We compare this
information with what previously known from IRAS and discuss the average
properties of radio galaxies in the redshift range 0.2 - 0.8. The FIR emission
cannot be accounted for by extrapolation of the synchrotron radio spectrum and
we attribute it to thermal dust emission. The average FIR luminosity is >=
6*10^11 L_sun. Over the observed frequency range the infrared spectrum can be
described by a power law with spectral index alpha >~1.0 +/- 0.2. Assuming the
emission to be due to dust, a range of temperatures is required, from >=80 K to
\~25 K. The dust masses required to explain the FIR emission range from 5*10^5
M_sun for the hotter component up to 2*10^8 M_sun for the colder one.
(abridged)

</DOC>
<DOC>
<DOCNO> 150506 </DOCNO>
Vertex Operators in $AdS_3\times S^3$ Background with NS_NS Flux using


  String equations for the vertex operators of type IIB on $AdS_3\times S^3$
background with NS-NS flux are calculated using Berkovits-Vafa-Witten
formalism. With suitable field definitions, the linearized field equations for
six-dimensional supergravity and a tensor multiplet on $AdS_3\times S^3$ are
recovered from these. We also discuss the massless degrees of freedom that
survive the $S^3$ Kaluza-Klein compactification and how our vertex operators
are related to the vertex operators introduced by Giveon, Kutasov and Seiberg.

</DOC>
<DOC>
<DOCNO> 72335 </DOCNO>
"Signature" neutrinos from photon sources at high redshift


  The temperature of the cosmic microwave background increases with redshift;
at sufficiently high redshift it becomes possible for ultrahigh-energy photons
and electrons to produce muons and pions through interactions with background
photons. At the same time, energy losses due to interactions with radio
background and intergalactic magnetic fields are negligible. The energetic
muons and pions decay, yielding a flux of ``signature'' neutrinos with energies
$E_\nu \sim 10^{17}$eV. Detection of these neutrinos can help understand the
origin of ultrahigh-energy cosmic rays.

</DOC>
<DOC>
<DOCNO> 121034 </DOCNO>
Abundance analysis of two extremely metal-poor stars from the


  We report on the first high spectral resolution analysis of extremely
metal-poor halo stars from the Hamburg/ESO objective-prism survey (HES). The
spectra were obtained with UVES at VLT-UT2. The two stars under investigation
(\object {HE 1303--2708} and \object {HE 1353--2735}) are main-sequence
turnoff-stars having metal abundances of [Fe/H]=-2.85 and -3.20, respectively.
The stellar parameters derived from the UVES spectra are in very good agreement
with those derived from moderate-resolution follow-up spectra. HE 1353--2735 is
a double-lined spectroscopic binary.
  The two stars nicely reproduce the strong scatter in [Sr/Fe] observed for
extremely metal-poor stars. While we see a strong Sr II $\lambda 4215$ {\AA}
line in the spectrum of HE 1303--2708 ([Sr/Fe]=-0.08), we can only give an
upper limit for HE 1353--2735 ([Sr/Fe]<-1.2), since the line is not detected.
We report abundances of Mg, Ca, Sc, Ti, Cr for both stars, and Co, Y for
respect to known trends for metal-poor stars.Lithium is also detected in these
stars, to a level which places them among Lithium-plateau metal-poor dwarfs.

</DOC>
<DOC>
<DOCNO> 117858 </DOCNO>
The Nature of Ultra-Luminous Compact X-Ray Sources in Nearby Spiral


  Studies were made of ASCA spectra of seven ultra-luminous compact X-ray
sources (ULXs) in nearby spiral galaxies; M33 X-8 (Takano et al. 1994), M81 X-6
(Fabbiano 1988b; Kohmura et al. 1994; Uno 1997), IC 342 Source 1 (Okada et al.
1998), Dwingeloo 1 X-1 (Reynolds et al. 1997), NGC 1313 Source B (Fabbiano &
Trinchieri 1987; Petre et al. 1994), and two sources in NGC 4565 (Mizuno et al.
1999). With the 0.5--10 keV luminosities in the range 10^{39-40} ergs/s, they
are thought to represent a class of enigmatic X-ray sources often found in
spiral galaxies. For some of them, the ASCA data are newly processed, or the
published spectra are reanalyzed. For others, the published results are quoted.
The ASCA spectra of all these seven sources have been described successfully
with so called multi-color disk blackbody (MCD) emission arising from
optically-thick standard accretion disks around black holes. Except the case of
M33 X-8, the spectra do not exhibit hard tails. For the source luminosities not
to exceed the Eddington limits, the black holes are inferred to have rather
high masses, up to ~100 solar masses. However, the observed innermost disk
temperatures of these objects, Tin = 1.1--1.8 keV, are too high to be
compatible with the required high black-hole masses, as long as the standard
accretion disks around Schwarzschild black holes are assumed. Similarly high
disk temperatures are also observed from two Galactic transients with
superluminal motions, GRO 1655-40 and GRS 1915+105. The issue of unusually high
disk temperature may be explained by the black hole rotation, which makes the
disk get closer to the black hole, and hence hotter.

</DOC>
<DOC>
<DOCNO> 102123 </DOCNO>
Relations between some cardinals in the absence of the Axiom of Choice


  If we assume the axiom of choice, then every two cardinal numbers are
comparable. In the absence of the axiom of choice, this is no longer so. For a
few cardinalities related to an arbitrary infinite set, we will give all the
possible relationships between them, where possible means that the relationship
is consistent with the axioms of set theory. Further we investigate the
relationships between some other cardinal numbers in specific permutation
models and give some results provable without using the axiom of choice.

</DOC>
<DOC>
<DOCNO> 11662 </DOCNO>
Exact solution of a many body problem with nearest and next-nearest


  Recently a partially solvable many-body problem with nearest and next-nearest
neighbour interactions is proposed [cond-mat/9904121]. We show that by adding a
suitably chosen momentum dependent nearest neighbour interaction, such a model
can be converted into an integrable system with Lax operator formulation and
related conserved quantities. We also solve the eigenvalue problem for the
model exactly and as a byproduct obtain some identities involving associated
Laguerre polynomials.

</DOC>
<DOC>
<DOCNO> 178777 </DOCNO>
$\pi-N$ from an Extended Effective Field Theory


  Third order chiral perturbation theory accounts for the $\pi-N$ scattering
phase shift data out to energies slightly below the position of the $\Delta$
resonance. The low energy constants are not accurately determined. Explicit
inclusion of the $\Delta$ field is favored.

</DOC>
<DOC>
<DOCNO> 14147 </DOCNO>
Vortex Structure in Superconducting Stripe States


  The vortex structure in superconducting stripe states is studied according to
the Bogoliubov-de Gennes theory on the two-dimensional Hubbard model with
nearest-neighbor sites pairing interaction. The vortex is trapped at the
outside region of the stripe line, where the superconductivity is weak. The
superconducting coherence length along the stripe direction becomes long. There
are no eminent low-energy electronic states even near the vortex core. These
characters resemble the Josephson vortex in layered superconductors under a
parallel field.

</DOC>
<DOC>
<DOCNO> 13819 </DOCNO>
Cooper pair tunneling in circuits with substantial dissipation: the


  We propose a circuit comprising a linear array of three small-capacitance
superconducting tunnel junctions with miniature resistors (R > R_Q = h/4e^2 =
6.5 kOhm) attached to the ends of this array. Owing to the Coulomb blockade
effect and the effect of dissipative environment on the supercurrent, this
circuit enables the gate-controlled transfer of individual Cooper pairs. The
first experiment on operating the Al-Cr Cooper pair R-pump is described.

</DOC>
<DOC>
<DOCNO> 122467 </DOCNO>
Discovery of the Bright Trans-Neptunian Object 2000 EB173


  We describe the discovery circumstances and photometric properties of 2000
EB173, now one of the brightest trans-Neptunian objects (TNOs) with opposition
magnitude m_R=18.9 and also one of the largest Plutinos, found with the
drift-scanning camera of the QUEST Collaboration, attached to the 1-m Schmidt
telescope of the National Observatory of Venezuela. We measure B-V = 0.99 +/-
0.14 and V-R = 0.57 +/- 0.05, a red color observed for many fainter TNOs. At
our magnitude limit m_R = 20.1 +/- 0.20, our single detection reveals a sky
density of 0.015 (+0.034, -0.012) TNOs per deg^2 (the error bars are 68%
confidence limits), consistent with fainter surveys showing a cumulative number
proportional to 10^0.5m_R. Assuming an inclination distribution of TNOs with
FWHM exceeding 30 deg, it is likely that one hundred to several hundred objects
brighter than m_R=20.1 remain to be discovered.

</DOC>
<DOC>
<DOCNO> 9645 </DOCNO>
SUE: A Special Purpose Computer for Spin Glass Models


  The use of last generation Programmable Electronic Components makes possible
the construction of very powerful and competitive special purpose computers. We
have designed, constructed and tested a three-dimensional Spin Glass model
dedicated machine, which consists of 12 identical boards. Each single board can
simulate 8 different systems, updating all the systems at every clock cycle.
The update speed of the whole machine is 217ps/spin with 48 MHz clock
frequency. A device devoted to fast random number generation has been developed
and included in every board. The on-board reprogrammability permits us to
change easily the lattice size, or even the update algorithm or the action. We
present here a detailed description of the machine and the first runs using the
Heat Bath algorithm.

</DOC>
<DOC>
<DOCNO> 174596 </DOCNO>
Analysis of data on low-energy gamma-p scattering and determination of


  An analysis of all experimental data of 50's - 90's on elastic gamma-p
scattering at photon energies below 150 MeV (10 experimental works) is
performed in order to determine the electric (alpha_p) and magnetic (beta_p)
polarizabilities of the proton. A fit of these data with the two free
parameters, alpha_p and beta_p, embedded into a theoretical cross section
obtained on the basis of finite-energy s-channel dispersion relations gives the
following world-average values of the proton polarizabilities (in units of
10^{-4} fm^3): alpha_p = 11.7 +- 0.8 (stat+sys) +- 0.7 (model), beta_p = 2.3 +-
0.9 (stat+sys) +- 0.7 (model), where the first error takes into account
statistical and systematic errors of the experimental cross sections and the
second error does model uncertainties in the theoretical cross section.

</DOC>
<DOC>
<DOCNO> 8063 </DOCNO>
Phase Ordering in Chaotic Map Lattices with Additive Noise


  We present some result about phase separation in coupled map lattices with
additive noise. We show that additive noise acts as an ordering agent in this
class of systems. In particular, in the weak coupling region, a suitable
quantity of noise leads to complete ordering. Extrapolating our results at
small coupling, we deduce that this phenomenon could take place also in the
limit of zero coupling.

</DOC>
<DOC>
<DOCNO> 11881 </DOCNO>
Simulation of Flux Lines with Columnar Pins: Bose Glass and Entangled


  Using path integral Monte Carlo we simulate a 3D system of up to 1000
magnetic flux lines by mapping it onto a system of interacting bosons in
(2+1)D. With increasing temperature we find a first order melting of flux lines
from an ordered solid to an entangled liquid signalled by a finite entropy jump
and sharp discontinuities in the defect density and the structure factor
$S({\bf G})$ at the first reciprocal lattice vector. In the presence of a small
number of strong columnar pins, we find that the crystal is transformed into a
Bose glass phase with patches of crystalline order nucleated around the trapped
vortices but with no overall positional or orientational order. This glassy
phase melts into a defected entangled liquid through a continuous transition.

</DOC>
<DOC>
<DOCNO> 119637 </DOCNO>
Astronomers and the Science Citation Index, 1981--1997


  The Institute for Science Information (ISI) has generated two lists of
citation information for astronomers that are uniquely restricted both as to
the years surveyed for the cited papers, and the years surveyed for the citing
papers. The main list gives citation data for 62,813 physicists and astronomers
whose journal papers were cited 100 times or more from 1981.0 to 1997.5 by
papers published during the same time interval. The second list gives the 200
most-cited papers/year published in refereed astronomical journals from
1981-1996, as cited in papers in those same journals from 1981.0-1998.0.
Astronomer names were selected from various sources. From this work an
Astronomy Citation Database (ACD) has been constructed, containing citation
data for 6458+ astronomers, plus additional data for 173 astronomers and the
top-10 cited papers published 1981-1996. Various problems, both substantial and
subtle, of producing a reasonably fair citation database are detailed. Chief
among these are whether to assign either parital or full credit for each author
on a given paper. Whether one is honored with one of the top astronomy
lifetime-awards is a strong function of how well your work stands out as your
own, and in what kind of publications you publish (e.g., the ISI does not keep
track of papers in meeting proceedings/books/catalogs). Name confusion affects
this kind of analysis to the extent that that it would take an enormous effort
to disentangle its effects and, even then, not all name confusion would be
settled. A ``modest proposal'' is made that our professional field (and others)
go to a system of uniquely associating an identification number to each author
on each paper to solve the name confusion problem.

</DOC>
<DOC>
<DOCNO> 102620 </DOCNO>
On the Global Regularity of Wave Maps in the Critical Sobolev Norm


  We extend the recent result of T.Tao to wave maps defined from the Minkowski
space of dimension >4 to a target Riemannian manifold which possesses a
``bounded parallelizable'' structure. This is the case of Lie groups,
homogeneous spaces as well as the hyperbolic spaces. General compact Riemannian
manifolds can be imbedded as totally geodesic submanifolds in bounded
parallelizable manifolds, and therefore are also covered, in principle, by our
result. Compactness of the target manifold, which seemed to play an important
role in Tao's result, turns out however to play no role in our discussion. Our
proof follows closely that of Tao's recent paper and is based, in particular,
on its remarkable microlocal gauge renormalization idea.

</DOC>
<DOC>
<DOCNO> 69282 </DOCNO>
Remarks on a Proposed Super-Kamiokande Test for Quantum Gravity Induced


  Lisi, Marrone, and Montanino have recently proposed a test for quantum
gravity induced decoherence effects in neutrino oscillations observed at
Super-Kamiokande. We comment here that their equations have the same
qualitative form as the energy conserving objective state vector reduction
equations discussed by a number of authors. However, using the Planckian
parameter value proposed to explain state vector reduction leads to a neutrino
oscillation effect many orders of magnitude smaller than would be detectable at
Super-Kamiokande. Similar estimates hold for the Ghirardi, Rimini, and Weber
spontaneous localization approach to state vector reduction, and our remarks
are relevant as well to proposed $K$ meson and $B$ meson tests of gravity
induced decoherence.

</DOC>
<DOC>
<DOCNO> 8065 </DOCNO>
High frequency ESR investigation on dynamical charge disproportionation


  A significant frequency dependence of the ESR line width is found in NaV_2O_5
between 34-100 K and the line width increases as the resonance frequency is
increased from 95 GHz to 760 GHz. The observed frequency dependence is
qualitatively explained in terms of the dynamical charge disproportionation.
The present results show the essential role of the internal charge degree of
freedom in a V-O-V bond. We have also proposed the existence of the
Dzyaloshinsky-Moriya interaction in the low temperature charge ordered phase
considering the breaking of the selection rule of ESR realized as the direct
observation of the spin gap excitation.

</DOC>
<DOC>
<DOCNO> 117921 </DOCNO>
X-ray flares on zero-age- and pre-main sequence stars in


  We present results of a systematic search for X-ray flares on young stars
observed during ROSAT PSPC observations of the Taurus-Auriga-Perseus region.
All pointed PSPC observations currently available from the ROSAT Public Data
Archive with known T Tauri stars, Pleiads, or Hyads in the field are analyzed
in order to study the evolution of coronal activity. 38 large flares can be
attributed to late-type stars. A flare rate is derived for the different
stellar samples making use of the flare duration and the observing time. We
investigate the influence of stellar parameters such as age, rotation and
multiplicity on individual flare parameters and the flare frequency.

</DOC>
<DOC>
<DOCNO> 11284 </DOCNO>
On the possibility of a metallic phase in granular superconducting films


  We investigate the possibility of finding a zero-temperature metallic phase
in granular superconducting films. We are able to identify the breakdown of the
conventional treatment of these systems as dissipative Bose systems. We do not
find a metallic state at zero temperature. At finite temperatures, we find that
the system exhibit crossover behaviour which may have implications for the
analysis of experimental results. We also investigate the effect of vortex
dissipation in these systems.

</DOC>
<DOC>
<DOCNO> 170713 </DOCNO>
Continuous variable cloning via network of parametric gates


  We propose an experimental scheme for the cloning machine of continuous
quantum variables through a network of parametric amplifiers working as
input-output four-port gates.

</DOC>
<DOC>
<DOCNO> 9229 </DOCNO>
Phase Diagram of Diluted Magnetic Semiconductor Quantum Wells


  The phase diagram of diluted magnetic semiconductor quantum wells is
investigated. The interaction between the carriers in the hole gas can lead to
first order ferromagnetic transitions, which remain abrupt in applied fields.
These transitions can be induced by magnetic fields or, in double-layer systems
by electric fields. We make a number of precise experimental predictions for
observing these first order phase transitions.

</DOC>
<DOC>
<DOCNO> 10762 </DOCNO>
Nuclear Spin Relaxation for Higher Spin


  We study the relaxation of a spin I that is weakly coupled to a quantum
mechanical environment. Starting from the microscopic description, we derive a
system of coupled relaxation equations within the adiabatic approximation.
These are valid for arbitrary I and also for a general stationary
non--equilibrium state of the environment. In the case of equilibrium, the
stationary solution of the equations becomes the correct Boltzmannian
equilibrium distribution for given spin I. The relaxation towards the
stationary solution is characterized by a set of relaxation times, the longest
of which can be shorter, by a factor of up to 2I, than the relaxation time in
the corresponding Bloch equations calculated in the standard perturbative way.

</DOC>
<DOC>
<DOCNO> 69194 </DOCNO>
The full spin structure of quarks in the nucleon


  We discuss bounds on the distribution and fragmentation functions that appear
at leading order in deep inelastic 1-particle inclusive leptoproduction or in
Drell-Yan processes. These bounds simply follow from positivity of the
quark-hadron scattering matrix elements and are an important guide in
estimating the magnitude of the azimuthal and spin asymmetries in these
processes. We focus on an example relevant for deep inelastic scattering at
relatively low energies.

</DOC>
<DOC>
<DOCNO> 170148 </DOCNO>
Correlation Functions and Spin


  The k-electron correlation function of a free chaotic electron beam is
derived with the spin degree of freedom taken into account. It is shown that it
can be expressed with the help of correlation functions for a polarized
electron beam of all orders up to k and the degree of spin polarization. The
form of the correlation function suggests that if the electron beam is not
highly polarized, observing multi-particle correlations should be difficult.
The result can be applied also to chaotic photon beams, the degree of spin
polarization being replaced by the degree of polarization.

</DOC>
<DOC>
<DOCNO> 69791 </DOCNO>
Probing Quantum Violations of the Equivalence Principle


  The joint realm of quantum mechanics and the general-relativistic description
of gravitation is becoming increasingly accessible to terrestrial experiments
and observations. In this essay we study the emerging indications of the
violation of equivalence principle (VEP). While the solar neutrino anomaly may
find its natural explanation in a VEP, the statistically significant
discrepancy observed in the gravitationally induced phases of neutron
interferometry seems to be the first indication of a VEP. However, such a view
would seem immediately challenged by the atomic interferometry results. The
latter experiments see no indications of VEP, in apparent contradiction to the
neutron interferometry results. Here we present arguments that support the view
that these, and related torsion pendulum experiments, probe different aspects
of gravity; and that current experimental techniques, when coupled to the
solar-neutrino data, may be able to explore quantum mechanically induced
violations of the equivalence principle. We predict quantum violation of the
equivalence principle (qVEP) for next generation of atomic interferometry
experiments. The prediction entails comparing free fall of two different linear
superpositions of Cesium atomic states.

</DOC>
<DOC>
<DOCNO> 80847 </DOCNO>
Nontrivial fixed point in nonabelian models


  We investigate the percolation properties of equatorial strips in the
two-dimensional O(3) nonlinear $\sigma$ model. We find convincing evidence that
such strips do not percolate at low temperatures, provided they are
sufficiently narrow. Rigorous arguments show that this implies the vanishing of
the mass gap at low temperature and the absence of asymptotic freedom in the
massive continuum limit. We also give an intuitive explanation of the
transition to a massless phase and, based on it, an estimate of the transition
temperature.

</DOC>
<DOC>
<DOCNO> 69074 </DOCNO>
Cosmological constant vs. quintessence


  There is some evidence that the Universe is presently undergoing accelerating
expansion. This has restored some credit to the scenarios with a non-vanishing
cosmological constant. From the point of view of a theory of fundamental
interactions, one may argue that a dynamical component with negative pressure
is easier to achieve. As an illustration, the quintessence scenario is
described and its shortcomings are discussed in connection with the nagging
``cosmological constant problem''.

</DOC>
<DOC>
<DOCNO> 8731 </DOCNO>
Bose condensates at high angular momenta


  We exploit the analogy with the Quantum Hall (QH) system to study weakly
interacting bosons in a harmonic trap. For a $\delta$-function interaction
potential the ``yrast'' states with $L\ge N(N-1)$ are degenerate, and we show
how this can be understood in terms of Haldane exclusion statistics. We present
spectra for 4 and 8 particles obtained by numerical and algebraic methods, and
demonstrate how a more general hard-core potential lifts the degeneracies on
the yrast line. The exact wavefunctions for N=4 are compared with trial states
constructed from composite fermions (CF), and the possibility of using
CF-states to study the low L region at high N is discussed.

</DOC>
<DOC>
<DOCNO> 69900 </DOCNO>
Influence of the Magnetic Field on the Fermion Scattering off Bubble and


  We investigate the scattering of fermions off domain walls at the electroweak
phase transition in presence of a magnetic field. We consider both the bubble
wall and the kink domain wall. We derive and solve the Dirac equation for
fermions with momentum perpendicular to the walls, and compute the transmission
and reflection coefficients. In the case of kink domain wall, we briefly
discuss the zero mode solutions localized on the wall. The possibile role of
the magnetic field for the electroweak baryogenesis is also discussed.

</DOC>
<DOC>
<DOCNO> 83141 </DOCNO>
BDD-based reasoning in the fluent calculus - first results


  The paper reports on first preliminary results and insights gained in a
project aiming at implementing the fluent calculus using methods and techniques
based on binary decision diagrams. After reporting on an initial experiment
showing promising results we discuss our findings concerning various techniques
and heuristics used to speed up the reasoning process.

</DOC>
<DOC>
<DOCNO> 118722 </DOCNO>
Galaxy Morphologies in the Cluster CL1358+62 at z=0.33


  We describe the morphological composition of a sample of 518 galaxies in the
field of CL1358+62 at z=0.33, drawn from a large HST mosaic covering 53 sq.
arcmin. The sample is complete to I=22, corresponding to M_V=-18.5 in the rest
frame. The galaxies have been independently classified by the authors of this
paper and by Alan Dressler. For galaxies with I<21, the two sets of classifiers
agree on the total early-type population, but disagree on the S0/E ratio. We
discuss the constraints on morphological evolution and the implication of the
differing S0/E ratios. We use our large body of spectra to make the
correspondence between morphological and spectral type.

</DOC>
<DOC>
<DOCNO> 117833 </DOCNO>
The Properties of Young Clusters in M82


  We present a detailed study of two luminous super star clusters in the
starburst galaxy M82. Spectra, covering 3250-8790 A at a resolution of 1.6 A,
were obtained at the 4.2 m William Herschel Telescope (WHT) for cluster F and
the highly reddened cluster L. We compare the strengths of the observed Balmer
absorption lines and the Balmer jump in the blue spectrum of F with theoretical
model cluster spectra using the PEGASE spectral synthesis code to derive an age
of 60+/-20 Myr. For cluster L, we find that the similarities in the strength of
the Ca II triplet and overall spectral appearance with cluster F suggest a
similar age. The brightness and compactness of cluster F make it an ideal
candidate for determining its dynamical mass by measuring the velocity
dispersion. We present the results of such an investigation based on echelle
spectra at a resolution of 8 km/s obtained at the WHT from 5760-9140 A. By
cross-correlating various wavelength regions in the spectrum of cluster F with
cool giant and supergiant template stars, we derive a velocity dispersion and,
by application of the virial theorem, determine a dynamical mass of 2 million
solar masses. We compare our derived mass with those determined for other young
super star clusters and discuss whether our derived parameters are consistent
with cluster F being able to survive to become a globular cluster.

</DOC>
<DOC>
<DOCNO> 83289 </DOCNO>
Brainstorm/J: a Java Framework for Intelligent Agents


  Despite the effort of many researchers in the area of multi-agent systems
(MAS) for designing and programming agents, a few years ago the research
community began to take into account that common features among different MAS
exists. Based on these common features, several tools have tackled the problem
of agent development on specific application domains or specific types of
agents. As a consequence, their scope is restricted to a subset of the huge
application domain of MAS. In this paper we propose a generic infrastructure
for programming agents whose name is Brainstorm/J. The infrastructure has been
implemented as an object oriented framework. As a consequence, our approach
supports a broader scope of MAS applications than previous efforts, being
flexible and reusable.

</DOC>
<DOC>
<DOCNO> 9065 </DOCNO>
From localization to delocalization in the quantum Coulomb glass


  We numerically investigate how electron-electron interactions influence the
transport properties of disordered electrons in two dimensions. Our study is
based on the quantum Coulomb glass model appropriately generalized to include
the spin degrees of freedom. In order to obtain the low-energy properties of
this model we employ the Hartree-Fock based diagonalization, an efficient
numerical method similar to the configuration interaction approach in quantum
chemistry. We calculate the d.c. conductance by means of the Kubo-Greenwood
formula and pay particular attention to the spin degrees of freedom. In
agreement with earlier results we find that electron-electron interactions can
cause delocalization. For spinful electrons this delocalization is
significantly larger than for spinless electrons.

</DOC>
<DOC>
<DOCNO> 69405 </DOCNO>
Some remarks on the epsilon-expansion of dimensionally regulated Feynman


  Some problems related to construction of the epsilon-expansion of
dimensionally regulated Feynman integrals are discussed. For certain classes of
diagrams, an arbitrary term of the epsilon-expansion can be expressed in terms
of log-sine integrals related to the polylogarithms. It is shown how the
analytic continuation of these functions can be constructed in terms of the
generalized Nielsen polylogarithms.

</DOC>
<DOC>
<DOCNO> 178410 </DOCNO>
Microscopic theories of neutrino-^{12}C reactions


  In view of the recent experiments on neutrino oscillations performed by the
LSND and KARMEN collaborations as well as of future experiments, we present new
theoretical results of the flux averaged $^{12}C(\nu_e,e^-)^{12}N$ and
$^{12}C(\nu_{\mu},{\mu}^-)^{12}N$ cross sections. The approaches used are
charge-exchange RPA, charge-exchange RPA among quasi-particles (QRPA) and the
Shell Model. With a large-scale shell model calculation the exclusive cross
sections are in nice agreement with the experimental values for both reactions.
The inclusive cross section for $\nu_{\mu}$ coming from the decay-in-flight of
$\pi^+$ is $15.2 \times 10^{-40} cm^2$ to be compared to the experimental value
of $12.4 \pm 0.3 \pm 1.8 \times 10^{-40} cm^2$, while the one due to $\nu_{e}$
coming from the decay-at-rest of $\mu^+$ is $16.4 \times 10^{-42} cm^2$ which
agrees within experimental error bars with the measured values. The shell model
prediction for the decay-in-flight neutrino cross section is reduced compared
to the RPA one. This is mainly due to the different kind of correlations taken
into account in the calculation of the spin modes and partially due to the
shell-model configuration basis which is not large enough, as we show using
arguments based on sum-rules.

</DOC>
<DOC>
<DOCNO> 100319 </DOCNO>
Sequences in non-commutative L^p-spaces


  Let $\cal M$ be a semi-finite von Neumann algebra equipped with a
distinguished faithful, normal, semi-finite trace $\tau$. We introduce the
notion of equi-integrability in non-commutative spaces and show that if a
rearrangement invariant quasi-Banach function space $E$ on the positive
semi-axis is $\alpha$-convex with constant 1 and satisfies a non-trivial lower
$q$-estimate with constant 1, then the corresponding non-commutative space of
measurable operators $E({\cal M}, \tau)$ has the following property: every
bounded sequence in $E({\cal M}, \tau)$ has a subsequence that splits into a
$E$-equi-integrable sequence and a sequence with pairwise disjoint projection
supports. This result extends the well known Kadec-Pe\l czy\'nski subsequence
decomposition for Banach lattices to non-commutative spaces. As applications,
we prove that for $1\leq p <\infty$, every subspace of $L^p(\cal M, \tau)$
either contains almost isometric copies of $\ell^p$ or is strongly embedded in
$L^p(\cal M, \tau)$.

</DOC>
<DOC>
<DOCNO> 150932 </DOCNO>
Stretched Strings in Noncommutative Field Theory


  Motivated by recent discussions of IR/UV mixing in noncommutative field
theories, we perform a detailed analysis of the non-planar amplitudes of the
bosonic open string in the presence of an external B-field at the one-loop
level. We carefully isolate, at the string theory level, the contribution which
is responsible for the IR/UV behavior in the field theory limit. We show that
it is a pure open string effect by deriving it from the factorization of the
one-loop amplitude into the disk amplitudes of intermediate open string
insertions. We suggest that it is natural to understand IR/UV mixing as the
creation of intermediate ``stretched strings''.

</DOC>
<DOC>
<DOCNO> 119660 </DOCNO>
The radiation driven winds of rotating B[e] supergiants


  We have formulated the momentum equation for sectorial line driven winds from
rotating stars including: (a) the oblateness of the star, (b) gravity darkening
(von Zeipel effect), (c) conservation of angular momentum, (d) line driving
specified by the force multiplier parameters (k, alpha, delta), (e) finite disk
correction factors for an oblate star with gravity darkening for both the
continuum and the line driving. The equations are solved numerically. We
calculated the distribution of the mass flux and the wind velocity from the
pole to the equator for the winds of B[e]-supergiants. Rotation decreases the
terminal velocity in the equatorial region but hardly affects the wind velocity
from the poles; it enhances the mass flux from the poles while the mass flux
from the equator remains nearly the same. These effects increase with
increasing rotation rates.
  We also calculated models with a bi-stability jump around 25 000 K, using
force multipliers recently calculated with a Monte Carlo technique. In this
case the mass flux increases drastically from the pole to the equator and the
terminal velocity decreases drastically from pole to equator. This produces a
density contrast in the wind rho(equator/pole) of about a factor 10 independent
of the rotation rate of the star. We suggest that the observed density contrast
of a factor 100 of the disks of B[e] stars may be reached by taking into
account the wind compression due to the trajectories of the gas above the
critical point towards the equatorial plane.

</DOC>
<DOC>
<DOCNO> 9307 </DOCNO>
Ferromagnetism and phase separation in one-dimensional d-p and periodic


  Using the Density Matrix Renormalization Group, we study metallic
ferromagnetism in a one-dimensional copper-oxide model which contains one
oxygen p-orbital and one copper d-orbital. The parameters for the d-p model can
be chosen so that it is similar to the one-dimensional periodic Anderson model.
For these parameters, we compare the ground-state phase diagram with that of
the Anderson model and find a ferromagnetic region analogous to one found in
the Anderson model, but which is pushed to somewhat higher densities and
interaction strengths. In both models, we find a region within the
ferromagnetic phase in which phase separation between a localized ferromagnetic
domain and a weakly antiferromagnetic regime occurs. We then choose a set of
parameter values appropriate for copper-oxide materials and explore the
ground-state phase diagram as a function of the oxygen-oxygen hopping strength
and the electron density. We find three disconnected regions of metallic
ferromagnetism and give physical pictures of the three different mechanisms for
ferromagnetism in these phases.

</DOC>
<DOC>
<DOCNO> 121844 </DOCNO>
The Central Velocity Field in NGC 253 : Possible Indication of a Bar


  We have investigated whether motion of gas in a bar-like potential can
account for the peculiar but systematic velocity field observed in the nuclear
region of the starburst galaxy NGC 253. This unusual velocity field with
gradients along both major and minor axes was revealed in a high resolution
($1.8^{\arcsec}\times 1.0^{\arcsec}$) H92$\alpha$ recombination line
observation by Anantharamiah and Goss (1996). A simple logarithmic potential is
used to model the bar. Assuming that the bulk of the gas flows along closed and
non-intersecting x1 (bar) and x2 (anti-bar) orbits of the bar potential, we
have computed the expected velocity field and position-velocity diagrams and
compared them with the observations. A comparison of the integrated CO
intensity maps with the spatial distribution of the x1 and x2 orbits in the
model indicates that the nuclear molecular gas in NGC 253 lies mainly on the x2
orbits. We also find that the velocity field observed in the central 100 pc
region in the H92$\alpha$ recombination line is well accounted for by the bar
model if most of the ionized gas resides in the inner x2 orbits. However, the
model is unable to explain the velocity field on a larger scale of $\sim 500$
pc observed using the OVRO interferometer with a resolution of
$5^{\arcsec}\times 3^{\arcsec}$. The direction of the observed CO velocity
field appears twisted compared to the model. We suggest that this perturbation
in the velocity field may be due to an accretion event that could have occurred
$10^7$ years ago.

</DOC>
<DOC>
<DOCNO> 101243 </DOCNO>
Classical representations for quantum-like systems through an axiomatics


  We introduce a definition for a 'hidden measurement system', i.e., a physical
entity for which there exist: (i) 'a set of non-contextual states of the entity
under study' and (ii) 'a set of states of the measurement context', and which
are such that all uncertainties are due to a lack of knowledge on the actual
state of the measurement context. First we identify an explicit criterion that
enables us to verify whether a given hidden measurement system is a
representation of a given couple $\Si,{\cal E}$ consisting of a set of states
$\Si$ and a set of measurements ${\cal E}$ ($=$ measurement system). Then we
prove for every measurement system that there exists at least one
representation as a hidden measurement system with $[0,1]$ as set of states of
the measurement context. Thus, we can apply this definition of a hidden
measurement system to impose an axiomatics for context dependence. We show that
in this way we always find classical representations (hidden measurement
representations) for general non-classical entities (e.g. quantum entities).

</DOC>
<DOC>
<DOCNO> 9199 </DOCNO>
Columnar Defects and Scaling Behavior in Quasi 2D Type II


  Persistent scaling behavior of magnetization in layered high $T_c$
superconductors with short--range columnar defects is explained within the
Ginzburg Landau theory. In the weak field region, the scaling function differs
from that of a clean sample and both the critical and crossing temperatures are
renormalized due to defects. In the strong field region, defects are
effectively suppressed and scaling function, as well as critical and crossing
temperatures are the same as in a clean superconductor. This picture is
consistent with recent experimental results

</DOC>
<DOC>
<DOCNO> 151207 </DOCNO>
Instanton-Sphaleron transition in the d = 2 Abelian-Higgs model on a


  The transition from the instanton-dominated quantum regime to the
sphaleron-dominated classical regime is studied in the $d=2$ abelian-Higgs
model when the spatial coordinate is compactified to $S^1$. Contrary to the
noncompactified case, this model allows both sharp first-order and smooth
second-order transitions depending on the size of the circle. This finding may
make the model a useful toy model for the analysis of baryon number violating
processes. Since the model can to a large extent be treated analytically, it
can also serve as a transparent prototype for the application of our method to
more complicated cases, such as those in higher dimensions.

</DOC>
<DOC>
<DOCNO> 151701 </DOCNO>
Dirac Spectrum in Adjoint QCD


  In this lecture we discuss some exact results for the low-lying spectrum of
the Dirac operator in adjoint QCD. In particular, we find an analytical
expression for the slope of the average spectral density. These results are
obtained by means of a generating function which is an extension of the QCD
partition function with fermionic and bosonic ghost quarks. The low-energy
limit of this generating function is completely determined by chiral
(super-)symmetries. Our results for the slope of the average spectral density
are consistent with the results for the scalar susceptibility which can be
obtained from the usual chiral Lagrangian.

</DOC>
<DOC>
<DOCNO> 121938 </DOCNO>
Lagrangian description of fluid flow with pressure in relativistic


  The Lagrangian description of fluid flow in relativistic cosmology is
extended to the case of flow accelerated by pressure. In the description, the
entropy and the vorticity are obtained exactly for the barotropic equation of
state. In order to determine the metric, the Einstein equation is solved
perturbatively, when metric fluctuations are small but entropy inhomogeneities
are large. Thus, the present formalism is applicable to the case when the
inhomogeneities are small in the large scale but locally nonlinear.

</DOC>
<DOC>
<DOCNO> 68277 </DOCNO>
Towards an Algebraic Classification of Calabi-Yau Manifolds I: Study of


  We present an inductive algebraic approach to the systematic construction and
classification of generalized Calabi-Yau (CY) manifolds in different numbers of
complex dimensions, based on Batyrev's formulation of CY manifolds as toric
varieties in weighted complex projective spaces associated with reflexive
polyhedra. We show how the allowed weight vectors in lower dimensions may be
extended to higher dimensions, emphasizing the roles of projection and
intersection in their dual description, and the natural appearance of
Cartan-Lie algebra structures. The 50 allowed extended four-dimensional vectors
may be combined in pairs (triples) to form 22 (4) chains containing 90 (91) K3
spaces, of which 94 are distinct, and one further K3 space is found using
duality. In the case of CY_3 spaces, pairs (triples) of the 10~270 allowed
extended vectors yield 4242 (259) chains with K3 (elliptic) fibers containing
730 additional K3 polyhedra. A more complete study of CY_3 spaces is left for
later work.

</DOC>
<DOC>
<DOCNO> 12655 </DOCNO>
Semiclassical theory of trapped fermionic dipoles


  We investigate the properties of a degenerate dilute gas of neutral fermionic
particles in a harmonic trap that interact via dipole-dipole forces. We employ
the semiclassical Thomas-Fermi method and discuss the Dirac correction to the
interaction energy. A nearly analytic as well as an exact numerical
minimization of the Thomas-Fermi-Dirac energy functional are performed in order
to obtain the density distribution. We determine the stability of the system as
a function of the interaction strength, the particle number, and the trap
geometry. We find that there are interaction strengths and particle numbers for
which the gas cannot be trapped stably in a spherically symmetric trap, but
both prolate and oblate traps will work successfully.

</DOC>
<DOC>
<DOCNO> 121997 </DOCNO>
First XMM-Newton observations of a cataclysmic variable II: the X-ray


  We present XMM-Newton X-ray spectra of the disc accreting cataclysmic
variable OY Car, which were obtained during the performance verification phase
of the mission. These data were taken 4 days after a short outburst. In the
EPIC spectra we find strong iron Kalpha emission with weaker iron Kbeta
emission together with silicon and sulphur lines. The spectra are best fitted
with a three temperature plasma model with a partial covering absorber.
Multiple temperature emission is confirmed by the emission lines seen in the
RGS spectrum and the H/He like intensity ratio for iron and sulphur which imply
temperatures of ~7keV and ~3keV respectively.

</DOC>
<DOC>
<DOCNO> 151044 </DOCNO>
Scale Invariance in the Causal Approach to Renormalization Theory


  The dilation invariance is studied in the framework of Epstein-Glaser
approach to renormalization theory. Some analogues of the Callan-Symanzik
equations are found and they are applied to the scalar field theory and to
Yang-Mills models. We find the interesting result that, if all the fields of
the theory have zero masses, then from purely cohomological consideration, one
can obtain the anomalous terms of logarithmic type.

</DOC>
<DOC>
<DOCNO> 40430 </DOCNO>
Measurements of BR (b -> tau- nubar_tau X) and BR (b -> tau- nubar_tau


  Inclusive branching ratios involving b to tau transitions are measured in
approximately four million hadronic Z decays collected by the ALEPH detector at
LEP. The fully-inclusive branching ratio b -> tau nu X and the semi-inclusive
branching ratio b -> tau nu D*+/- X are measured to be (2.43 +/- 0.20 +/-
0.25)% and (0.88 +/- 0.31 +/- 0.28)%, in agreement with the standard model
predictions. Upper limits on the branching fractions b -> tau nu and b -> s nu
nubar are set to 8.3 10**-4 and 6.4 10**-4 at the 90% C.L. These results allow
a 90% C.L. lower limit of 0.40 (GeV/c**2)**-1 to be set on the tan(beta)/mH+/-
ratio, in the framework of type-II two-Higgs-doublet mode

</DOC>
<DOC>
<DOCNO> 13667 </DOCNO>
Simulation of polymers in a curved box: Variable range bonding models


  We propose new polymer models for Monte Carlo simulation and apply them to a
polymer chain confined in a relatively thin box which has both curved and flat
sides, and show that either an ideal or an excluded-volume chain spends more
time in the curved region than in the flat region. The ratio of the probability
of finding a chain in the curved region and in flat region increases
exponentially with increasing chain length. The results for ideal chains are
quantitatively consistent with a previously published theory. We find that the
same effect appears with excluded-volume chains and a similar scaling relation
can be applied to them up to a certain length of the polymer.

</DOC>
<DOC>
<DOCNO> 99883 </DOCNO>
Elementary Factors and Reduced Minors for Linear Systems over


  In 1994, Sule presented the necessary and sufficient conditions of the
feedback stabilizability of systems over unique factorization domains in terms
of elementary factors and in terms of reduced minors. Recently, Mori and Abe
have generalized his theory over commutative rings. They have introduced the
notion of the generalized elementary factor, which is a~generalization of the
elementary factor, and have given the necessary and sufficient condition of the
feedback stabilizability. In this paper, we present two generalization of the
reduced minors. Using each of them, we state the necessary and sufficient
condition of the feedback stabilizability over commutative rings. Further we
present the relationship between the generalizations and the generalized
elementary factors.

</DOC>
<DOC>
<DOCNO> 170144 </DOCNO>
Two Qubits in the Dirac Representation


  A general two qubit system expressed in terms of the complete set of unit and
fifteen traceless, Hermitian Dirac matrices, is shown to exhibit novel features
of this system. The well-known physical interpretations associated with the
relativistic Dirac equation involving the symmetry operations of time-reversal
T, charge conjugation C, parity P, and their products are reinterpreted here by
examining their action on the basic Bell states. The transformation properties
of the Bell basis states under these symmetry operations also reveal that C is
the only operator that does not mix the Bell states whereas all others do. In a
similar fashion, expressing the various logic gates introduced in the subject
of quantum computers in terms of the Dirac matrices shows for example, that the
NOT gate is related to the product of time-reversal and parity operators.

</DOC>
<DOC>
<DOCNO> 152429 </DOCNO>
Physical sense of renormalizability


  A plausible physical interpretation of the renormalizability condition is
given. It is shown that renormalizable quantum field theories describe such
systems wherein the tendency to collapse associated with vacuum fluctuations of
attractive forces is suppressed by vacuum fluctuations of kinetic energy.
Relaying on the classification of topological types of evolution of point
particles and analysing the problem of the fall to the centre, we obtain a
general criterion for preventability of collapse which states that the spectrum
of the Hamiltonian must be bounded from below. The holographic principle is
used to explain the origin of anomalies and make precise the relation between
the renormalizability and the reversibility.

</DOC>
<DOC>
<DOCNO> 170360 </DOCNO>
Quantum nonlinear dynamics of continuously measured systems


  Classical dynamics is formulated as a Hamiltonian flow on phase space, while
quantum mechanics is formulated as a unitary dynamics in Hilbert space. These
different formulations have made it difficult to directly compare quantum and
classical nonlinear dynamics. Previous solutions have focussed on computing
quantities associated with a statistical ensemble such as variance or entropy.
However a more direct comparison would compare classical predictions to the
quantum for continuous simultaneous measurement of position and momentum of a
single system. In this paper we give a theory of such measurement and show that
chaotic behaviour in classical systems can be reproduced by continuously
measured quantum systems.

</DOC>
<DOC>
<DOCNO> 71901 </DOCNO>
Low-lying fermion modes, topology and light hadrons in quenched QCD


  We explore the properties of low lying eigenmodes of fermions in the quenched
approximation of lattice QCD. The fermion action is a recently proposed overlap
action and has exact chiral symmetry. We find that chiral zero-eigenvalue modes
are localized in space and their positions correlate strongly with the
locations (as defined through the density of pure gauge observables) of
instantons of the appropriate charge. Nonchiral modes are also localized with
peaks which are strongly correlated with the positions of both charges of
instantons. These correlations slowly die away as the fermion eigenvalue rises.
Correlators made of quark propagators restricted to these modes closely
reproduce ordinary hadron correlators at small quark mass in many channels. Our
results are in qualitative agreement with the expectations of instanton liquid
models.

</DOC>
<DOC>
<DOCNO> 83434 </DOCNO>
Static Analysis Techniques for Equational Logic Programming


  An equational logic program is a set of directed equations or rules, which
are used to compute in the obvious way (by replacing equals with ``simpler''
equals). We present static analysis techniques for efficient equational logic
programming, some of which have been implemented in $LR^2$, a laboratory for
developing and evaluating fast, efficient, and practical rewriting techniques.
Two novel features of $LR^2$ are that non-left-linear rules are allowed in most
contexts and it has a tabling option based on the congruence-closure based
algorithm to compute normal forms. Although, the focus of this research is on
the tabling approach some of the techniques are applicable to the untabled
approach as well. Our presentation is in the context of $LR^2$, which is an
interpreter, but some of the techniques apply to compilation as well.

</DOC>
<DOC>
<DOCNO> 85301 </DOCNO>
Cosmological Evolution of a Brane Universe in a Type 0 String Background


  We study the cosmological evolution of a D3-brane Universe in a type 0 string
background. We follow the brane-universe along the radial coordinate of the
background and we calculate the energy density which is induced on the brane
because of its motion in the bulk. We find that for some typical values of the
parameters and for a particular range of values of the scale factor of the
brane-universe, the effective energy density is dominated by a term
proportional to $\frac{1}{(loga)^{4}}$ indicating a slow varying inflationary
phase. For larger values of the scale factor the effective energy density takes
a constant value and the brane-universe enters its usual inflationary period.

</DOC>
<DOC>
<DOCNO> 84754 </DOCNO>
Equivalence Postulate and Quantum Origin of Gravitation


  We suggest that quantum mechanics and gravity are intimately related. In
particular, we investigate the quantum Hamilton-Jacobi equation in the case of
two free particles and show that the quantum potential, which is attractive,
may generate the gravitational potential. The investigation, related to the
formulation of quantum mechanics based on the equivalence postulate, is based
on the analysis of the reduced action. A consequence of this approach is that
the quantum potential is always non-trivial even in the case of the free
particle. It plays the role of intrinsic energy and may in fact be at the
origin of fundamental interactions. We pursue this idea, by making a
preliminary investigation of whether there exists a set of solutions for which
the quantum potential can be expressed with a gravitational potential leading
term which alone would remain in the limit hbar \to 0. A number of questions
are raised for further investigation.

</DOC>
<DOC>
<DOCNO> 118450 </DOCNO>
First order Fermi acceleration at multiple oblique shocks


  Numerical results for particle acceleration at multiple oblique shocks are
presented. We calculate the steady state spectral slope of test particles
accelerated by the first order Fermi process. The results are compared to
analytical treatments, for parameters, where the diffusion approximation does
apply. Effects of injection and finite shock extend are included
phenomenologically. We find the spectrum of accelerated particles to harden
substantially at multiple oblique shocks and discuss the influence of the
number of shocks compared to the obliquity itself.

</DOC>
<DOC>
<DOCNO> 10928 </DOCNO>
A New Stochastic Strategy for the Minority Game


  We present a variant of the Minority Game in which players who where
successful in the previous timestep stay with their decision, while the losers
change their decision with a probability $p$. Analytical results for different
regimes of $p$ and the number of players $N$ are given and connections to
existing models are discussed. It is shown that for $p \propto 1/N$ the average
loss $\sigma^2$ is of the order of 1 and does not increase with $N$ as for
other known strategies.

</DOC>
<DOC>
<DOCNO> 84563 </DOCNO>
Response of massive bodies to gravitational waves


  The response of a massive body to gravitational waves is described on the
microscopic level. The results shed a new light on the commonly used oscillator
model. It is shown that apart from the non-resonant tidal motion the energy
transfer from a gravitational wave to an electromagnetically coupled body is in
general restricted to the surface, whereas gravitational coupling gives rise to
bulk excitation of quadrupole modes, but several orders of magnitude smaller.
These results do not contradict standard theory, rather present a different
viewpoint. A microscopic detector making use of the effect is suggested.

</DOC>
<DOC>
<DOCNO> 9322 </DOCNO>
Mean-field study of the interplay between antiferromagnetism and d-wave


  The interplay between antiferromagnetism and d-wave superconductivity is
studied in a mean-field approximation for a generic microscopic Hamiltonian
with short-range repulsion and near-neighbor attraction. In the presence of
competing microscopic interactions, the phase boundaries of antiferromagnetic
and superconducting states are significantly modified in some region of the
doping-temperature plane. The transition between superconductivity and
antiferromagnetism occurs through a phase where both order parameters coexist
with a third, dynamically generated, spin-triplet amplitude. This dynamical
generation of a new order parameter is not restricted to a system with
antiferromagnetism and d-wave superconductivity, but is a generic feature for
fermionic systems. The dynamically generated spin-triplet order parameter is
found to be robust to variations in the mean-field Hamiltonian.

</DOC>
<DOC>
<DOCNO> 120284 </DOCNO>
HST observations of FR I radiogalaxies: what do they tell us about the


  We explore the viability of the unification of BL Lacs and FR I radio
galaxies by comparing the core emission of radio galaxies with those of BL
Lacs, taking advantage of the newly measured optical nuclear luminosity of FR I
sources. The spectral properties of complete samples are studied in the
radio-optical luminosity plane: we calculate the predicted luminosity of BL
Lacs when observed off-axis, in the frame of a simple one-zone model. We find
that the bulk Lorentz factors required in order to account for the observed
luminosities are significantly smaller than those implied by other, both
observational and theoretical, considerations. In order to reconcile these
results with the unification scheme, velocity structures in the jet are
suggested, where a fast spine is surrounded by a slower layer.

</DOC>
<DOC>
<DOCNO> 71856 </DOCNO>
A Toy Model of Colour Screening in the Proton


  In hadronic collisions, the mini-jet cross section is formally divergent in
the limit pT -> 0. We argue that this divergence is tamed by some effective
colour correlation length scale of the hadron. A toy model of the hadronic
structure is introduced, that allows an estimate of the screening effects, and
especially their energy dependence.

</DOC>
<DOC>
<DOCNO> 83514 </DOCNO>
Learning Complexity Dimensions for a Continuous-Time Control System


  This paper takes a computational learning theory approach to a problem of
linear systems identification. It is assumed that input signals have only a
finite number k of frequency components, and systems to be identified have
dimension no greater than n. The main result establishes that the sample
complexity needed for identification scales polynomially with n and
logarithmically with k.

</DOC>
<DOC>
<DOCNO> 117685 </DOCNO>
A near infrared photometric plane for ellipticals and bulges of spirals


  We report the existence of a single plane in the space of global photometric
parameters describing elliptical galaxies and the bulges of early type spiral
galaxies. The three parameters which define the plane are obtained by fitting
the Sersic form to the brightness distribution obtained from near-infrared K
band images. We find, from the range covered by their shape parameters, that
the elliptical galaxies form a more homogeneous population than the bulges.
Known correlations like the Kormendy relation are projections of the
photometric plane. The existence of the plane has interesting implications for
bulge formation models.

</DOC>
<DOC>
<DOCNO> 68961 </DOCNO>
Ultrahigh energy neutrino physics


  We discuss a problem concerning the ultrahigh energy neutrino propagation
through the Earth. We present calculation of the neutrino-nucleon cross section
at high energies, based on the unifed evolution equation at small x.
 We also show the solution of the transport equation for different neutrino
fluxes originating from active galactic nuclei, gamma ray bursts and top-down
model.

</DOC>
<DOC>
<DOCNO> 13835 </DOCNO>
Algebra versus analysis in statistical mechanics and quantum field


  I contrast the profound differences in the ways in which algebra and analysis
are used in physics. In particular I discuss the fascinating phenomenon that
theoretical physicists devote almost all their efforts to algebraic problems
even though all problems of experimental interest require some methods of
analysis.

</DOC>
<DOC>
<DOCNO> 170468 </DOCNO>
Anonymous-key quantum cryptography and unconditionally secure quantum


  A new cryptographic tool, anonymous quantum key technique, is introduced that
leads to unconditionally secure key distribution and encryption schemes that
can be readily implemented experimentally in a realistic environment. If
quantum memory is available, the technique would have many features of
public-key cryptography; an identification protocol that does not require a
shared secret key is provided as an illustration. The possibility is also
indicated for obtaining unconditionally secure quantum bit commitment protocols
with this technique.

</DOC>
<DOC>
<DOCNO> 10767 </DOCNO>
Projecting the Kondo Effect: Theory of the Quantum Mirage


  A microscopic theory is developed for the projection (quantum mirage) of the
Kondo resonance from one focus of an elliptic quantum corral to the other
focus. The quantum mirage is shown to be independent of the size and the shape
of the ellipse, and experiences \lambda_F/4 oscillations (\lambda_F is the
surface-band Fermi wavelength) with an increasing semimajor axis length. We
predict an oscillatory behavior of the mirage as a function of a weak magnetic
field applied perpendicular to the sample.

</DOC>
<DOC>
<DOCNO> 101727 </DOCNO>
Nilpotent Lie Groups in Clifford Analysis: Five Directions for Research


  The aim of the paper is to popularise nilpotent Lie groups (notably the
Heisenberg group and alike) in the context of Clifford analysis and related
models of mathematical physics. It is argued that these groups are
underinvestigated in comparison with other classical branches of analysis. We
list five general directions which seem to be promising for further research.
Keywords: Clifford analysis, Heisenberg group, nilpotent Lie group,
Segal-Bargmann space, Toeplitz operators, singular integral operators,
pseudodifferential operators, functional calculus, joint spectrum, quantum
mechanics, spinor field.

</DOC>
<DOC>
<DOCNO> 178477 </DOCNO>
Light Front Quantization--A Technique for Relativistic and Realistic


  Applications of relativistic light front dynamics to computing wave functions
of heavy nuclei are reviewed. The motivation for this is the desire to find
wave functions, expressed in terms of the plus-momentum variable, that simplify
the analyses of high energy experiments such as deep inelastic scattering,
Drell-Yan production, (e,e') and (p,p').Some examples of ordinary quantum
mechanics are solved to show that the formalism is tractable. Light-front
quantization is reviewed briefly and applied to: infinite nuclear matter within
the mean field approximation; a simple static source theory; finite nuclei
using the mean field approximation; low-energy pion-nucleon scattering using a
chiral Lagrangian; nucleon-nucleon scattering, within the one boson exchange
approximation; and, infinite nuclear matter including the effects of
two-nucleon correlations. Standard good results for nuclear saturation
properties are obtained, with a possible improvement in the computed nuclear
compressibility. Manifest rotational invariance is not used as an aid in doing
calculations, but it does emerge in the results. It seems that nuclear physics
can be done in a manner in which modern nuclear dynamics is respected, boost
invariance in the $z$-direction is preserved, and in which rotational
invariance is maintained. A salient feature is that $\omega,\sigma$ and $\pi$
mesons are important constituents of nuclei. It seems possible to find
Lagrangians that yield reasonable descriptions of nuclear deep inelastic
scattering and Drell-Yan reactions. Furthermore, the presence of the $\sigma$
and $\omega$ mesons could provide a nuclear enhancement of the ratio of the
cross sections for longitudinally and transversely polarized virtual photons in
accord with recent measurements by the HERMES collaboration.

</DOC>
<DOC>
<DOCNO> 11802 </DOCNO>
Phase Transitions in liquid Helium 3


  The phase transitions of liquid Helium 3 are described by truncations of an
exact nonperturbative renormalization group equation. The location of the first
order transition lines and the jump in the order parameter are computed
quantitatively. At the triple point we find indications for partially universal
behaviour. We suggest experiments that could help to determine the effective
interactions between fermion pairs.

</DOC>
<DOC>
<DOCNO> 100269 </DOCNO>
A Uniform Approach to Antiferromagnetic Heisenberg Spins on Low


  Using group theoretical methods we show for both the triangular and square
lattices that in the continuum limit the antiferromagnetic order parameter
lives on SO3 without respect of the initial lattice. For the antiferromagnetic
chain we recover the Haldane decomposition. This order parameter interacts with
a local gauge field rather than with a global one as implicitly suggested in
the literature which in our approach appears in a rather natural manner. In
fact this merely corresponds to a novel extension of the spin group by a local
gauge field. This analysis based on the real division algebras applies to low
dimensional lattices.

</DOC>
<DOC>
<DOCNO> 70662 </DOCNO>
The shape function in field theory


  The shape function describes (non-perturbative) Fermi motion effects in
semi-inclusive heavy flavour decay. Its renormalization properties are
substantially dependent on the kind of ultraviolet regulator used. For example,
the double logarithm that appears at one loop is larger by a factor 2 in
dimensional regularization than in lattice regularization. We show that
factorization of long-distance effects inside the shape function is achieved
with any regulator considered.

</DOC>
<DOC>
<DOCNO> 13760 </DOCNO>
Voltage-flux-characteristics of asymmetric dc SQUIDs


  We present a detailed analysis of voltage-flux V(Phi)-characteristics for
asymmetric dc SQUIDs with various kinds of asymmetries. For finite asymmetry
alpha_I in the critical currents of the two Josephson junctions, the minima in
the V(Phi)-characteristics for bias currents of opposite polarity are shifted
along the flux axis by Delta_Phi = (alpha_I)*(beta_L) relative to each other;
beta_L is the screening parameter. This simple relation allows the
determination of alpha_I in our experiments on YBa_2Cu_3O_(7-x} dc SQUIDs and
comparison with theory. Extensive numerical simulations within a wide range of
beta_L and noise parameter Gamma reveal a systematic dependence of the transfer
function V_Phi on alpha_I and alpha_R (junction resistance asymmetry). As for
the symmetric dc SQUID, V_Phi factorizes into
g(Gamma*beta_L)*f(alpha_I,beta_L), where now f also depends on alpha_I. For
\beta_L below five we find mostly a decrease of V_Phi with increasing alpha_I,
which however can only partially account for the frequently observed
discrepancy in V_Phi between theory and experiment for high-T_c dc SQUIDs.

</DOC>
<DOC>
<DOCNO> 9214 </DOCNO>
Scaling in the Integer Quantum Hall Effect: interactions and low


  Recent developments in the scaling theory of the integer quantum Hall effect
are discussed. In particular, the influence of electron-electron interactions
on the critical behavior are studied. It is further argued that recent
experiments on the disappearance of the quantum Hall effect at low magnetic
fields support rather than disprove the scaling theory, when interpreted
properly.

</DOC>
<DOC>
<DOCNO> 12468 </DOCNO>
Magnetic properties of the S=1/2 quasi-one-dimensional antiferromagnet


  We report single crystal growth and magnetic susceptibility and neutron
diffraction studies of the S=1/2 quasi-1D antiferromagnet CaCu2O3. The
structure of this material is similar to that of the prototype two-leg
spin-ladder compound SrCu2O3. However, the Cu-O-Cu bond angle in the ladder
rungs in CaCu2O3 is equal to 123 deg, and therefore the magnetic interaction
along the rungs is expected to be much weaker in this material. At high
temperatures, the magnetic susceptibility of CaCu2O3 can be decomposed into a
contribution from 1D antiferromagnetic chains of finite-size chain segments
together with a weak Curie contribution. The intrachain magnetic exchange
constant, determined from the magnetic susceptibility measurements, is 2000 K.
CaCu2O3 undergoes a Neel transition at T_N=25 K with ordering wavevector of
(0.429(5), 0.5, 0.5). The magnetic structure is incommensurate in the direction
of the frustrated interchain interaction. Weak commensurate (0.5, 0.5, 0.5)
magnetic peaks are also observed below T_N. Application of a magnetic field
induces a metamagnetic transition at which the incommensurability of the
magnetic structure is substantially reduced. The material possesses only
short-range magnetic order above the transition field.

</DOC>
<DOC>
<DOCNO> 99873 </DOCNO>
On the valuation of Asian options: integral representations


  This paper derives integral representations for the Black-Scholes price of
arithmetic-average Asian options. Their proof is by Laplace inverting the 1992
Laplace transform of Geman-Yor using complex analytic methods. The analysis
ultimately rests on the gamma function which in this sense is at the base of
Asian options. The results of Geman-Yor are corrected and their validitity is
extended.

</DOC>
<DOC>
<DOCNO> 9692 </DOCNO>
Electrical Conductivity in Magnesium-Doped Al_2 O_3 Crystal at Moderate


  AC and DC electrical measurements between 273 and 800 K were used to
characterize the electrical conductivity of Al_2 O_3:Mg single crystals
containing [Mg]^{0} center. At low fields contacts are blocking. At high
fields, electrical current flows steadily through the sample and the I-V
characteristic corresponds to a directly biased barrier whit a series
resistance (bulk resistance). AC measurements yield values for the junction
capacitance as well as for the sample resistance, and provide perfectly
reproducible conductivity values. The conductivity varies linearly whit the
[Mg]^{0} concentration and a thermal activation energy of 0.68 eV was obtained,
which agrees very well with the activation energy previously reported for
motion of free holes.

</DOC>
<DOC>
<DOCNO> 118190 </DOCNO>
The SIMBAD astronomical database


  Simbad is the reference database for identification and bibliography of
astronomical objects. It contains identifications, `basic data', bibliography,
and selected observational measurements for several million astronomical
objects. Simbad is developed and maintained by CDS, Strasbourg. Building the
database contents is achieved with the help of several contributing institutes.
Scanning the bibliography is the result of the collaboration of CDS with
bibliographers in Observatoire de Paris (DASGAL), Institut d'Astrophysique de
Paris, and Observatoire de Bordeaux. When selecting catalogues and tables for
inclusion, priority is given to optimal multi-wavelength coverage of the
database, and to support of research developments linked to large projects. In
parallel, the systematic scanning of the bibliography reflects the diversity
and general trends of astronomical research.
  A WWW interface to Simbad is available at: http://simbad.u-strasbg.fr/Simbad

</DOC>
<DOC>
<DOCNO> 70753 </DOCNO>
Effective theories and black hole production in warped compactifications


  We investigate aspects of the four-dimensional effective description of brane
world scenarios based on warped compactification on anti-de Sitter space. The
low-energy dynamics is described by visible matter gravitationally coupled to a
``dark'' conformal field theory. We give the linearized description of the 4d
stress tensor corresponding to an arbitrary 5d matter distribution. In
particular a 5d falling particle corresponds to a 4d expanding shell, giving a
4d interpretation of a trajectory that misses a black hole only by moving in
the fifth dimension. Breakdown of the effective description occurs when either
five-dimensional physics or strong gravity becomes important. In scenarios with
a TeV brane, the latter can happen through production of black holes near the
TeV scale. This could provide an interesting experimental window on quantum
black hole dynamics.

</DOC>
<DOC>
<DOCNO> 122762 </DOCNO>
Discovery of the Slowest X-Ray Pulsar in the SMC, AX J0049.5-7323, with


  The discovery of coherent pulsations with ASCA from an X-ray source, AX
J0049.5-7323, is reported. The barycentric period was determined to be 755.5
+/- 0.6 s, which is the longest among X-ray pulsators in the SMC. The X-ray
spectrum has been found to be unchanged through ASCA observations, with a
photon index of ~0.8 and a luminosity of ~5e35 erg s^-1 (0.7-10 keV). Archival
data of the Einstein and the ROSAT satellites indicate that the flux has been <
1e-12 erg s^-1 cm^-2 (< 5e35 erg s^-1) for over 20 years and exhibits a
variability with a factor of >10. We argue that AX J0049.5-7323 is an X-ray
pulsar with a Be star companion.

</DOC>
<DOC>
<DOCNO> 11491 </DOCNO>
Droplet shapes on structured substrates and conformal invariance


  We consider the finite-size scaling of equilibrium droplet shapes for fluid
adsorption (at bulk two-phase co-existence) on heterogeneous substrates and
also in wedge geometries in which only a finite domain $\Lambda_{A}$ of the
substrate is completely wet. For three-dimensional systems with short-ranged
forces we use renormalization group ideas to establish that both the shape of
the droplet height and the height-height correlations can be understood from
the conformal invariance of an appropriate operator. This allows us to predict
the explicit scaling form of the droplet height for a number of different
domain shapes. For systems with long-ranged forces, conformal invariance is not
obeyed but the droplet shape is still shown to exhibit strong scaling
behaviour. We argue that droplet formation in heterogeneous wedge geometries
also shows a number of different scaling regimes depending on the range of the
forces. The conformal invariance of the wedge droplet shape for short-ranged
forces is shown explicitly.

</DOC>
<DOC>
<DOCNO> 117267 </DOCNO>
Predicting Optimal Lengths of Random Knots


  In thermally fluctuating long linear polymeric chain in solution, the ends
come from time to time into a direct contact or a close vicinity of each other.
At such an instance, the chain can be regarded as a closed one and thus will
form a knot or rather a virtual knot. Several earlier studies of random
knotting demonstrated that simpler knots show their highest occurrence for
shorter random walks than more complex knots. However up to now there were no
rules that could be used to predict the optimal length of a random walk, i.e.
the length for which a given knot reaches its highest occurrence. Using
numerical simulations, we show here that a power law accurately describes the
relation between the optimal lengths of random walks leading to the formation
of different knots and the previously characterized lengths of ideal knots of
the corresponding type.

</DOC>
<DOC>
<DOCNO> 119011 </DOCNO>
TeV Gamma Rays Expected from Supernova Remnants in Different Uniform


  Calculations of the expected TeV $\gamma$-ray emission, produced by
accelerated cosmic rays (CRs) in nuclear collisions, from supernova remnants
evolving in a uniform interstellar medium (ISM) are presented. The aim is to
study the sensitivity of $\gamma$-ray production to a physical parameter set.
Apart from its general proportionality to N_H, it is shown that the
$\gamma$-ray production essentially depends upon the ratio of the CR diffusion
coefficient $\kappa$ to a critical value $\kappa_{crit}=10(B_0/5
\mu{G})(N_H/0.3 {cm}^{-3})^{-1/3}\kappa_B$, where B_0 and N_H are the magnetic
field and hydrogen number density of the ISM, and $\kappa_B$ denotes the Bohm
diffusion coefficient. If $\kappa$ is of the same order or lower than
$\kappa_{crit}$, then the peak TeV $\gamma$-ray flux in the Sedov evolutionary
phase, normalized to a distance of 1 kpc, is about 10^{-10}(N_H/0.3 {cm}^{-3})
photons cm^{-2} s^{-1}. For a CR diffusion coefficient that is significantly
larger than $\kappa_{crit}$, the CR cutoff energy is less than 10 TeV and the
expected $\gamma$-ray flux at 1 TeV is considerably below the presently
detectable level of 10^{-12} photons cm^{-2} s^{-1}. The same is of course true
for a SNR in the rarified, so-called hot ISM.

</DOC>
<DOC>
<DOCNO> 119643 </DOCNO>
New Detremination Method of Primordial Li Abundance


  We discuss the primordial nucleosynthesis in lepton asymmetric Universe
models. In order to better estimate the universal baryon-mass density parameter
$\Omega_b$, we try to remove the uncertainty from the theoretical prediction of
primordial $^7$Li abundance. We propose a new method to determine the
primordial $^7$Li by the use of isotopic abundance ratio $^7$Li/$^6$Li in the
interstellar medium which exhibits the minimum effects of the stellar
processes.

</DOC>
<DOC>
<DOCNO> 118555 </DOCNO>
Extracting Energy from Accretion into Kerr Black Hole


  The highest efficiency of converting rest mass into energy by accreting
matter into a Kerr black hole is ~ 31% (Thorne 1974). We propose a new process
in which periods of accretion from a thin disk, and the associated spin-up of
the black hole, alternate with the periods of no accretion and magnetic
transfer of energy from the black hole to the disk. These cycles can repeat
indefinitely, at least in principle, with the black hole mass increasing by ~
66% per cycle, and up to ~ 43% of accreted rest mass radiated away by the disk.

</DOC>
<DOC>
<DOCNO> 11622 </DOCNO>
Fluctuation-Dissipation-Theorem violation during the formation of a


  The relationship between the conductivity and the polarization noise is
measured in a gel as a function of frequency in the range $1Hz - 40Hz$. It is
found that at the beginning of the transition from a fluid like sol to a solid
like gel the fluctuation dissipation theorem is strongly violated. The
amplitude and the persistence time of this violation are decreasing functions
of frequency. At the lowest frequencies of the measuring range it persists for
times which are about 5% of the time needed to form the gel. This phenomenology
is quite close to the recent theoretical predictions done for the violation of
the fluctuation dissipation theorem in glassy systems.

</DOC>
<DOC>
<DOCNO> 67731 </DOCNO>
CP Violaing Phases In SUSY GUT Models


  Supersymmetric CP violating phases are examined within the framework of
gravity mediated supergravity grand unified models with R parity invariance for
models with a light ($\stackrel{<}{\sim} 1$ TeV) particle spectrum. In the
minimal model, the nearness of the t quark Landau pole naturally suppresses the
t-quark cubic soft breaking parameter at the electroweak scale allowing the
electron and neutron experimental electric dipole moment (EDM) constraints to
be satisfied with a large GUT scale phase. However, the EDM constraints require
that $\theta_B$, the quadratic soft breaking parameter phase be small at the
electroweak scale unless tan$\beta\stackrel{<}{\sim}3$, which then implies that
at the GUT scale this phase must be large and highly fine tuned to satisfy
radiative breaking of $SU(2)\times U(1)$. Similar results hold for non minimal
models, and a possible GUT model is discussed where all GUT scale CP violating
phases are naturally small (i.e. O($10^{-2})$). An interesting D-brane model is
examined which enhances the size of the phases over much of the parameter space
at the electroweak sector for tan$\beta\stackrel{<}{\sim} 5$, but still
possesses the fine tuning problem at the GUT scale.

</DOC>
<DOC>
<DOCNO> 69238 </DOCNO>
Democratic-type neutrino mass matrix


  We consider the democratic-type neutrino mass matrix and show that this
matrix predicts the atmospheric neutrino mixing to be almost maximal, $\sin^2
2\theta_{atm}>0.999$ as well as the large CP violation (the CP violation phase
in the standard form is maximal $\delta=\pi/2$). We construct the $Z_3$
symmetric dimension five effective Lagrangian with two up-type Higgs doublets
and show that this Lagrangian leads to the democratic neutrino mass matrix.
Furthermore, we consider the restricted model with one up-type Higgs doublet
and obtain the prediction, $0.87<\sin^2 2\theta_{sol}<8/9$.

</DOC>
<DOC>
<DOCNO> 71668 </DOCNO>
Extensive air showers with TeV-scale quantum gravity


  One of the possible consequences of the existence of extra degrees of freedom
beyond the electroweak scale is the increase of neutrino-nucleon cross sections
($\sigma_{\nu N}$) beyond Standard Model predictions. At ultra-high energies
this may allow the existence of neutrino-initiated extensive air showers. In
this paper, we examine the most relevant observables of such showers. Our
analysis indicates that the future Pierre Auger Observatory could be
potentially powerful in probing models with large compact dimensions.

</DOC>
<DOC>
<DOCNO> 100709 </DOCNO>
Littlewood-Paley theory and the T(1) theorem with non doubling measures


  Let $\mu$ be a Borel measure on $R^d$ which may be non doubling. The only
condition that $\mu$ must satisfy is $\mu(B(x,r))\leq C r^n$ for all $x\in
R^d$, $r>0$, and for some fixed $0<n\leq d$. In this paper, we develop
Littlewood-Paley theory for functions in $L^p(\mu)$. One of the main
difficulties is the construction of reasonable approximations of the identity
for obtaining a Calderon type reproducing formula. Moreover, it is shown that
the T(1) theorem for n-dimensional Calderon-Zygmund operators, without doubling
assumptions, can be proved using the Littlewood-Paley decomposition that is
obtained for $L^2(\mu)$ functions, as in the classical case of homogeneous
spaces.

</DOC>
<DOC>
<DOCNO> 150416 </DOCNO>
The Reeh-Schlieder property for ground states


  Recently it has been shown that the Reeh-Schlieder property w.r.t. thermal
equilibrium states is a direct consequence of locality, additivity and the
relativistic KMS condition. Here we extend this result to ground states.

</DOC>
<DOC>
<DOCNO> 13695 </DOCNO>
Fast growth at low temperature in vacancy-mediated phase-separation


  We study the phase-separation dynamics of a two-dimensional Ising model where
A and B particles can only exchange position with a vacancy. In a wide range of
temperatures the kinetics is dominated, during a long preasymptotic regime, by
diffusion processes of particles along domain interfaces. The dynamical
exponent z associated to this mechanism differs from the one usually expected
for Kawasaki dynamics and is shown to assume different values depending on
temperature and relative AB concentration. At low temperatures, in particular,
domains grow as t^{1/2}, for equal AB volume fractions.

</DOC>
<DOC>
<DOCNO> 13269 </DOCNO>
Random matrix theory for systems with an approximate symmetry and widths


  We discuss a random matrix model of systems with an approximate symmetry and
present the spectral fluctuation statistics and eigenvector characteristics for
the model. An acoustic resonator like, e.g., an aluminium plate may have an
approximate symmetry. We have measured the frequency spectrum and the widths
for acoustic resonances in thin aluminium plates, cut in the shape of the
so-called three-leaf clover. Due to the mirror symmetry through the middle
plane of the plate, each resonance of the plate belongs to one of two mode
classes and we show how to separate the modes into these two classes using
their measured widths. We compare the spectral statistics of each mode class
with results for the Gaussian orthogonal ensemble. By cutting a slit of
increasing depth on one face of the plate, we gradually break the mirror
symmetry and study the transition that takes place as the two classes are
mixed. Presenting the spectral fluctuation statistics and the distribution of
widths for the resonances, we find that this transition is well described by
the random matrix model.

</DOC>
<DOC>
<DOCNO> 102731 </DOCNO>
Equilibrium Fluctuations for Lattice Gases


  The authors in a previous paper proved the hydrodynamic incompressible limit
in $d\ge 3$ for a thermal lattice gas, namely a law of large numbers for the
density, velocity field and energy. In this paper the equilibrium fluctuations
for this model are studied and a central limit theorem is proved for a suitable
modification of the vector fluctuation field $\z(t)$, whose components are the
density, velocity and energy fluctuations fields.
  We consider a modified fluctuation field $\xi^\e(t)=\exp \{-\ve^{-1}t
E\}\z^\ve$, where $E$ is the linearized Euler operator around the equilibrium
and prove that $\xi^\e(t)$ converges to a vector generalized Ornstein-Uhlenbeck
process $\xi(t)$, which is formally solution of the stochastic differential
equation $d \xi(t)=N\xi(t)dt+ B dW_t$, with $ BB^*=-2 NC$, where $C$ is the
compressibility matrix, $N$ is a matrix whose entries are second order
differential operators and $B$ is a mean zero Gaussian field. The relation
$-2NC=BB^*$ is the fluctuation-dissipation relation.

</DOC>
<DOC>
<DOCNO> 71815 </DOCNO>
Physics potential of the LHC


  The basic aim of physics studies at the LHC is to unravel the mechanism
responsible for the spontaneous symmetry breaking in the Standard Model (SM).
 In the currently accepted theoretical picture, this translates into finding
`direct' experimental evidence for the Higgs sector. TeV scale supersymmetry
(SUSY) provides a very attractive solution to the `naturalness' problem that
theories with elementary scalar fields have. Hence in this talk I will
summarise the physics potential of the LHC for searching for Higgs and
Supersymmetry as well as for measurement of the parameters of the Higgs sector
and the SUSY model. Theories with localised gravity (and large extra
dimensions) give a credible option to have Standard Model without the attendant
`naturalness' problems. I will therefore also summarise the potential of LHC to
probe these `large' extra dimensions.

</DOC>
<DOC>
<DOCNO> 68208 </DOCNO>
Non-ladder Extended Renormalization Group Analysis of the Dynamical


  The order parameters of dynamical chiral symmetry breaking in QCD, the
dynamical mass of quarks and the chiral condensates, are evaluated by
numerically solving the Non-Perturbative Renormalization Group (NPRG)
equations. We employ an approximation scheme beyond ``the ladder'', that is,
beyond the (improved) ladder Schwinger-Dyson equations. The chiral condensates
are enhanced compared with the ladder ones, which is phenomenologically
favorable. The gauge dependence of the order parameters is fairly reduced in
this scheme.

</DOC>
<DOC>
<DOCNO> 152540 </DOCNO>
Non-Abelian BFFT embedding, Schr\"odinger quantization and the anomaly


  We embed the O(N) nonlinear sigma model in a non-Abelian gauge theory. As a
first class system, it is quantized using two different approaches: the
functional Schr\"odinger method and the non-local field-antifield procedure.
Firstly, the quantization is performed with the functional Schr\"{o}dinger
method, for N=2, obtaining the wave functionals for the ground and excited
states. In the second place, using the BV formalism we compute the one-loop
anomaly. This important result shows that the classical gauge symmetries,
appearing due to the conversion via BFFT method, are broken at the quantum
level.

</DOC>
<DOC>
<DOCNO> 68484 </DOCNO>
Achieving renormalization-scale- and scheme-independence in Pade-related


  Previously developed Pade-related method of resummation for QCD observables,
which achieves exact renormalization-scale-invariance, is extended so that the
scheme-invariance is obtained as well. The dependence on the leading scheme
parameter $c_2$ is eliminated by a variant of the method of the principle of
minimal sensitivity. The subleading parameter $c_3$ in the approximant is then
fixed in such a way that the correct known location of the leading infrared
renormalon pole is reproduced. Thus, $beta$-functions which go beyond the last
perturbatively calculated order in the observable are used. The
$\beta$-functions in the approximant are quasianalytically continued by Pade
approximants. Two aspects of nonperturbative physics are accounted for in the
presented resummation: a mechanism of quasianalytic continuation from the weak-
into the strong-coupling regime, and the (approximant-specific) contribution of
the leading infrared renormalon. The case of the Bjorken polarized sum rule is
considered as a specific example of how the method works.

</DOC>
<DOC>
<DOCNO> 116952 </DOCNO>
The Beam Halo Experiment at the LEDA Facility


  Due to the potentially adverse effects of the generation of halo particles in
intense proton beams, it is imperative to have a clear understanding of the
mechanisms that can lead to halo formation for current and proposed high-
intensity linacs. To this end a theoretical model has been developed, which
indicates that protons under the combined influence of strong space charge
forces and periodic focussing in a linear transport channel can be kicked into
halo orbits. However, no experimental measurements of beam halo in proton beams
have yet been carried out. In this paper we report the progress of an effort to
carry out an experiment to measure beam-halo using the existing high- intensity
proton beam of the LEDA facility. A linear transport channel has been assembled
with the appropriate diagnostics for measuring the expected small beam
component in the beam halo as a function of beam parameters. The experiment is
based on the use of an array of high-dynamic-range wire and beam scrapers to
determine the halo and core profiles along the transport channel. Details of
the experimental design, the expected halo measurement properties will be
presented.

</DOC>
<DOC>
<DOCNO> 119425 </DOCNO>
Far-UV FUSE spectroscopy of the OVI resonance doublet in Sand2 (WO)


  We present Far-Ultraviolet Spectroscopic Explorer (FUSE) spectroscopy of Sand
2, a LMC WO-type Wolf-Rayet star, revealing the OVI resonance P Cygni doublet
at 1032-38A. These data are combined with HST/FOS ultraviolet and Mt Stromlo
2.3m optical spectroscopy, and analysed using a spherical, non-LTE,
line-blanketed code. Our study reveals exceptional stellar parameters:
T*=150,000K, v_inf=4100 km/s, log (L/Lo)=5.3, and Mdot=10^-5 Mo/yr if we adopt
a volume filling factor of 10%. Elemental abundances of C/He=0.7+-0.2 and
O/He=0.15(-0.05+0.10) by number qualitatively support previous recombination
line studies. We confirm that Sand 2 is more chemically enriched in carbon than
LMC WC stars, and is expected to undergo a supernova explosion within the next
50,000 yr.

</DOC>
<DOC>
<DOCNO> 102679 </DOCNO>
A New Look at The Crossed-Product of a C*-algebra by an Endomorphism


  We give a new definition for the crossed-product of a C*-algebra A by a
*-endomorphism \alpha, which depends not only on the pair (A,\alpha) but also
on the choice of a transfer operator (defined in the paper). With this we
generalize some of the earlier constructions in the situations in which they
behave best (e.g. for monomorphisms with hereditary range), but we get a
different and perhaps more natural outcome in other situations. For example, we
show that the Cuntz-Krieger algebra O_A arises as the result of our
construction when applied to the corresponding Markov subshift and a very
natural transfer operator.

</DOC>
<DOC>
<DOCNO> 9241 </DOCNO>
Electron-Phonon Interactions in Correlated Systems: Adiabatic Expansion


  We use the dynamical mean field theory to develop a systematic and
computationally tractable method for studying electron-phonon interactions in
systems with arbitrary electronic correlations. The method is formulated as an
adiabatic expansion around the limit of static phonons. No specific electronic
groundstate is assumed. We derive an effective low-frequency phonon action
whose coefficients are static local correlation functions of the underlying
electron system. We identify the correct expansion parameters. At a critical
electron-phonon interaction strength the system undergoes a transition to a
polaronic state. We determine the location of this polaronic instability in the
presence of electron-electron interactions, doping, and quantum lattice
fluctuations and present the formalism needed for study of the electron
self-energy and effective mass.

</DOC>
<DOC>
<DOCNO> 170534 </DOCNO>
Invariant Polynomial Functions on k qudits


  We study the polynomial functions on tensor states in $(C^n)^{\otimes k}$
which are invariant under $SU(n)^k$. We describe the space of invariant
polynomials in terms of symmetric group representations. For $k$ even, the
smallest degree for invariant polynomials is $n$ and in degree $n$ we find a
natural generalization of the determinant. For $n,d$ fixed, we describe the
asymptotic behavior of the dimension of the space of invariants as
$k\to\infty$. We study in detail the space of homogeneous degree 4 invariant
polynomial functions on $(C^2)^{\otimes k}$.

</DOC>
<DOC>
<DOCNO> 85044 </DOCNO>
Black hole formation from massive scalar field collapse in the


  We study the spherically symmetric collapse of a real, minimally coupled,
massive scalar field in an asymptotically Einstein-de Sitter spacetime
background. By means of an eikonal approximation for the field and metric
functions, we obtain a simple analytical criterion---involving the physical
size and mass scales (the field's inverse Compton wavelength and the spacetime
gravitational mass) of the initial matter configuration---for generic
(non-time-symmetric) initial data to collapse to a black hole. This analytical
condition can then be used to place constraints on the initial primordial black
hole spectrum, by considering spherical density perturbations that re-entered
the horizon during an early matter-dominated phase that immediately followed
inflation.

</DOC>
<DOC>
<DOCNO> 39690 </DOCNO>
The E791 Parallel Architecture Data Acquisition System


  To collect data for the study of charm particle decays, we built a high speed
data acquisition system for use with the E791 magnetic spectrometer at
Fermilab. The DA system read out 24000 channels in 50 uS. Events were accepted
at the rate of 9000 per second. Eight large FIFOs were used to buffer event
segments, which were then compressed and formatted by 54 processors housed in 6
VME crates. Data was written continuously to 42 Exabyte tape drives at the rate
of 9.6 Mb/s. During the 1991 fixed target run at Fermilab, 20 billion physics
events were recorded on 24000 8 mm tapes; this 50 Tb (Terabyte) data set is now
being analyzed.

</DOC>
<DOC>
<DOCNO> 170301 </DOCNO>
Resonance Offset Tailored Pulses for NMR Quantum Computation


  We describe novel composite pulse sequences which act as general rotors and
thus are suitable for nuclear magnetic resonance (NMR) quantum computation. The
Resonance Offset Tailoring To Enhance Nutations (ROTTEN) approach permits
perfect compensation of off-resonance errors at two selected frequencies placed
symmetrically around the frequency of the RF source.

</DOC>
<DOC>
<DOCNO> 121008 </DOCNO>
R-mode oscillations of rapidly rotating Newtonian stars - A new


  We have developed a new numerical scheme to solve r-mode oscillations of {\it
rapidly rotating polytropic stars} in Newtonian gravity. In this scheme, Euler
perturbations of the density, three components of the velocity are treated as
four unknown quantities together with the oscillation frequency. For the basic
equations of oscillations, the compatibility equations are used instead of the
linearized equations of motion.
  By using this scheme, we have solved the classical r-mode oscillations of
rotational equilibrium sequences of polytropes with the polytropic indices $N =
0.5, 1.0$ and 1.5 for $m = 2, 3$ and 4 modes. Here $m$ is the rank of the
spherical harmonics $Y_l^m$. These results have been applied to investigate
evolution of uniformly rotating hot young neutron stars by considering the
effect of gravitational radiation and viscosity. We have found that the maximum
angular velocities of neutron stars are around 10-20% of the Keplerian angular
velocity irrespective of the softness of matter. This confirms the results
obtained from the analysis of r-modes with the slow rotation approximation
employed by many authors.

</DOC>
<DOC>
<DOCNO> 121883 </DOCNO>
Primary proton spectrum between 200 TeV and 1000 TeV observed with the


  Since 1996, a hybrid experiment consisting of the emulsion chamber and burst
detector array and the Tibet-II air-shower array has been operated at
Yangbajing (4300 m above sea level, 606 g/cm^2) in Tibet. This experiment can
detect air-shower cores, called as burst events, accompanied by air showers in
excess of about 100 TeV. We observed about 4300 burst events accompanied by air
showers during 690 days of operation and selected 820 proton-induced events
with its primary energy above 200 TeV using a neural network method. Using this
data set, we obtained the energy spectrum of primary protons in the energy
range from 200 to 1000 TeV. The differential energy spectrum obtained in this
energy region can be fitted by a power law with the index of -2.97 $\pm$ 0.06,
which is steeper than that obtained by direct measurements at lower energies.
We also obtained the energy spectrum of helium nuclei at particle energies
around 1000 TeV.

</DOC>
<DOC>
<DOCNO> 119176 </DOCNO>
Studies of Binary Star Cluster Candidates in the Bar of the LMC. I: SL


  We present a detailed study of the cluster pair SL 353 & SL 349. This
candidate binary cluster is located at the northwestern rim of the LMC bar.
Based on photometric data we find that both clusters are coeval with an age of
550 +/- 100 Myr. We use the Ca II triplet in the spectra of individual red
giants to derive radial velocities. Both components of the binary cluster
candidate show very similar mean velocities (approx. 274 +/- 10 km/sec for SL
349 and approx. 279 +/- 4 km/sec for SL 353) while the field stars show lower
velocities (approx. 240 +/- 19 km/sec). These findings suggest a common origin
of the two clusters from the same GMC. In this sense the cluster pair may
constitute a true binary cluster. We furthermore investigate the stellar
densities in and around the star clusters and compare them with isopleths
created from artificial, interacting as well as non-interacting star clusters.
Gravitational interaction leads to a distortion which can also be found in the
observed pair.

</DOC>
<DOC>
<DOCNO> 101714 </DOCNO>
Fallen Cardinals


  We prove that for every singular cardinal mu of cofinality omega, the
complete Boolean algebra compP_mu(mu) contains as a complete subalgebra an
isomorphic copy of the collapse algebra Comp Col(omega_1,mu^{aleph_0}).
Consequently, adding a generic filter to the quotient algebra
P_mu(mu)=P(mu)/[mu]^{<mu} collapses mu^{aleph_0} to aleph_1. Another corollary
is that the Baire number of the space U(mu) of all uniform ultrafilters over mu
is equal to omega_2. The corollaries affirm two conjectures by Balcar and
Simon.
  The proof uses pcf theory.

</DOC>
<DOC>
<DOCNO> 67904 </DOCNO>
Present knowledge of the Cabibbo-Kobayashi-Maskawa matrix


  A complete review of the Cabibbo-Kobayashi-Maskawa (CKM) matrix elements and
of the experimental methods for their determination is presented. A critical
analysis of the relevant experimental results, and in particular of the most
recent ones, allows to improve the accuracies of all the matrix elements. A
chi-square minimization with the three-family unitarity constraint on the CKM
matrix is performed to test the current interpretation of the CP violating
phenomena inside the Standard Model. A complete and unambiguous solution
satisfying all the imposed constraints is found. As a by-product of the fit,
the precision on the values of the matrix elements is further increased and it
is possible to obtain estimates for the important CP violation observables $sin
2\beta$, $sin 2\alpha$ and $\gamma$. Finally, an independent estimation of the
CKM elements based on a Bayesian approach is performed. This complementary
method constitutes a check of the results obtained, providing also the
probability functions of the CKM elements and of the related quantities.

</DOC>
<DOC>
<DOCNO> 68567 </DOCNO>
Light-Cone Representation of the Spin and Orbital Angular Momentum of


  The matrix elements of local operators such as the electromagnetic current,
the energy momentum tensor, angular momentum, and the moments of structure
functions have exact representations in terms of light-cone Fock state
wavefunctions of bound states such as hadrons. We illustrate all of these
properties by giving explicit light-cone wavefunctions for the two-particle
Fock state of the electron in QED, thus connecting the Schwinger anomalous
magnetic moment to the spin and orbital momentum carried by its Fock state
constituents. We also compute the QED one-loop radiative corrections for the
form factors for the graviton coupling to the electron and photon. Although the
underlying model is derived from elementary QED perturbative couplings, it in
fact can be used to simulate much more general bound state systems by applying
spectral integration over the constituent masses while preserving all of the
Lorentz properties, giving explicit realization of the spin sum rules and other
local matrix elements. The role of orbital angular momentum in understanding
the "spin crisis" problem for relativistic systems is clarified. We also prove
that the anomalous gravitomagnetic moment B(0) vanishes for any composite
system. This property is shown to follow directly from the Lorentz boost
properties of the light-cone Fock representation and holds separately for each
Fock state component. We show how the QED perturbative structure can be used to
model bound state systems while preserving all Lorentz properties. We thus
obtain a theoretical laboratory to test the consistency of formulae which have
been proposed to probe the spin structure of hadrons.

</DOC>
<DOC>
<DOCNO> 69325 </DOCNO>
Reduction of affine two-loop WZNW model, the Toda system coupled to the


  The conformal affine Toda model coupled to the matter field (CATM) is
obtained through a classical reduction of the $sl(2)^{(1)}$ affine two-loop
WZNW model. After spontaneously broken the conformal symmetry by means of BRST
analysis, we end up with an effective theory, the so called affine Toda model
coupled to the matter (ATM). Further, using a bosonization technique we recover
from this theory the sine-Gordon model plus a free massless scalar field. The
ATM model is considered as a QCD-motivated integrable field theory, since it
describes various features in the baryonic sector of the low-energy effective
Lagrangian of QCD in two dimensions with one flavor and two colors. Imposing
the equivalence of the Noether and topological currrents as a constraint, it is
shown that the intercharge ``quark''- ``anti-quark'' static potential reveals a
linear confinement behavior for large intercharge separation.

</DOC>
<DOC>
<DOCNO> 9313 </DOCNO>
A New Universality for Random Sequential Deposition of Needles


  Percolation and jamming phenomena are investigated for random sequential
deposition of rectangular needles on $d=2$ square lattices. Associated
thresholds $p_c^{perc}$ and $p_c^{jam}$ are determined for various needle
sizes. Their ratios $p_c^{perc} / p_c^{jam}$ are found to be a constant $0.62
\pm 0.01$ for all sizes. In addition the ratio of jamming thresholds for
respectively square blocks and needles is also found to be a constant $0.79 \pm
0.01$. These constants exhibit some universal connexion in the geometry of
jamming and percolation for both anisotropic shapes (needles versus square
lattices) and isotropic shapes (square blocks on square lattices). A universal
empirical law is proposed for all three thresholds as a function of $a$.

</DOC>
<DOC>
<DOCNO> 12214 </DOCNO>
Experimental Test of Condensate-Excitation Theories of the Fractional


  It is shown that the description of the FQHE as condensation of the electron
system into a ground state with fractionally charged excitations is
incompatible with experimental observations. The nature of the Hall voltage in
fractional plateaux as a chemical potential difference eliminates the
condensate as current carrier and the temperature dependence of longitudinal
conductance eliminates the excitation picture of charge carriers.

</DOC>
<DOC>
<DOCNO> 13559 </DOCNO>
Numerical Renormalization Group Study of Kondo Effect in Unconventional


  Orbital degrees of freedom of a Cooper pair play an important role in the
unconventional superconductivity. To elucidate the orbital effect in the Kondo
problem, we investigated a single magnetic impurity coupled to Cooper pairs
with a $p_x +i p_y$ ($d_{x^2-y^2}+id_{xy}$) symmetry using the numerical
renormalization group method. It is found that the ground state is always a
spin doublet. The analytical solution for the strong coupling limit explicitly
shows that the orbital dynamics of the Cooper pair generates the spin 1/2 of
the ground state.

</DOC>
<DOC>
<DOCNO> 151651 </DOCNO>
Tachyon Condensation on Fuzzy Sphere and Noncommutative Solitons


  We study a brane-antibrane system and a non-BPS D-brane in SU(2) WZW model.
We first discuss the tachyon condensation using the vertex operator formalism
and find the generation of codimension two D-branes after the condensation. Our
result is consistent with the recent interpretation that a D2-brane is a bound
state of D0-branes. Then we investigate the world volume effective theory on a
non-BPS D-brane. It becomes a field theory on the ``fuzzy sphere'' when the
level is sent to infinity. The most interesting feature is that there exist the
noncommutative tachyonic solitons and we can identify them with D0-branes. We
also discuss the brane-antibrane system from the world volume point of view and
comment on the relation to the noncommutative version of the index theorem.

</DOC>
<DOC>
<DOCNO> 122103 </DOCNO>
Fundamental Properties and Distances of LMC Eclipsing Binaries II. HV


  We have determined the distance to a second eclipsing binary system (EB) in
the Large Magellanic Cloud, HV982 (~B1 IV-V + ~B1 IV-V). The measurement of the
distance -- among other properties of the system -- is based on optical
photometry and spectroscopy and space-based UV/optical spectrophotometry. The
analysis combines the ``classical'' EB study of light and radial velocity
curves, which yields the stellar masses and radii, with a new analysis of the
observed energy distribution, which yields the effective temperature,
metallicity, and reddening of the system plus the distance ``attenuation
factor'', essentially (radius/distance)^2. Combining the results gives the
distance to HV982, which is 50.2 +/- 1.2 kpc. This distance determination
consists of a detailed study of well-understood objects (B stars) in a
well-understood evolutionary phase (core H burning), and is free of the biases
and uncertainties that plague various other techniques. After correcting for
the location of HV982, we find an implied distance to the optical center of the
LMC's bar of d(LMC) = 50.7 +/- 1.2 kpc. This result differs by nearly 5 kpc
from our earlier result for the EB HV2274, which implies a bar distance of 45.9
kpc. These results may reflect either marginally compatible measures of a
unique LMC distance or, alternatively, suggest a significant depth to the
stellar distribution in the LMC. Some evidence for this latter hypothesis is
discussed.

</DOC>
<DOC>
<DOCNO> 10734 </DOCNO>
Power laws and collapsing dynamics of a trapped Bose-Einstein condensate


  The critical behavior of collective modes and the collapsing dynamics of
trapped Bose-Einstein condensates with attractive interactions are studied
analytically and numerically. The time scales of these dynamics both below and
above the critical point of the collapse are found to obey power laws with a
single parameter of N/N_c - 1, where N is the number of condensate atoms and
N_c is the critical number. The collapsing condensate eventually undergoes
rapid implosion, which occurs several times intermittently, and then the
implosion turns to an explosion. The release energy of the explosion is found
to be proportional to the square of the interaction strength, inversely
proportional to the three-body recombination rate, and independent of the
number of condensate atoms and the trap frequency.

</DOC>
<DOC>
<DOCNO> 170364 </DOCNO>
Analogical Modeling and Quantum Computing


  This paper serves as a bridge between quantum computing and analogical
modeling (a general theory for predicting categories of behavior in varying
contexts). Since its formulation in the early 1980s, analogical modeling has
been successfully applied to a variety of problems in language. Several
striking similarities between quantum mechanics and analogical modeling have
recently been noted: (1) traditional statistics can be derived from a
non-statistical basis by assuming data occurrences are accessed through a
spin-up state (given two equally probable quantum states, spin-up and
spin-down); (2) the probability of predicting a particular outcome is
determined by the squaring of an underlying linear measure and is the result of
decoherence (which occurs when a quantum system is observed); and (3) a natural
measure of certainty (called the agreement) is based on one chance of guessing
the right outcome and corresponds to the integrated squaring of Schroedinger's
wave equation.
  Analogical modeling considers all possible combiantions of a given context of
n variables, which is classical terms leads to an exponential explosion on the
order of 2**n. This paper proposes a quantum computational solution to this
exponentiality by applying a cycle of reversible quantum operators to all 2**n
possibilities, thus reducing the time and space of analogical modeling to a
polynomial order.

</DOC>
<DOC>
<DOCNO> 174442 </DOCNO>
Neutrino Detection using Lead Perchlorate


  We discuss the possibility of using lead perchlorate as a neutrino detector.
The primary neutrino interactions are given along with some relevant properties
of the material.

</DOC>
<DOC>
<DOCNO> 8562 </DOCNO>
Magnetooptical effects in quantum wells irradiated with light pulses


  The method of detection and investigation of the magnetopolaron effect in the
semiconductor quantum wells (QW) in a strong magnetic field, based on pulse
light irradiation and measuring the reflected and transmitted pulses, has been
proposed. It has been shown that a beating amplitude on the frequencies,
corresponding to the magnetopolaron energy level splitting, depends strongly
from the exciting pulse width. The existence of the time points of the total
reflection and total transparency has been predicted. The high orders of the
perturbation theory on electron-electromagnetic field interaction have been
taken into account.

</DOC>
<DOC>
<DOCNO> 39707 </DOCNO>
Production of light stabilized radion at high energy hadron collider


  In this paper we use the conformal anomaly in QCD to derive the coupling of
light radion to gluons in the Randall-Sundrum model and use it to compute the
radion production cross section at hadron colliders by gluon fusion. We find
that the radion production cross section by gluon fusion at LHC would exceed
that of the higgs boson by a factor that lies between 7 and 8 over most of the
range. The decay modes of the radion are similar to that of the SM higgs boson.
But the striking feature is the enhancement of radion to 2-photon and radion to
2-gluon branching ratio over the SM case. Utilising this, we then discuss the
possible search strategies of such scalars at Tevatron and LHC. Using the
$\gamma \gamma$ decay mode one can explore/exclude radion mass upto 1 TeV. Even
with the current collected data at the Tevatron, one can exclude radion mass
upto 120 GeV for $\vphi$= 1 TeV.

</DOC>
<DOC>
<DOCNO> 100876 </DOCNO>
Exact solutions of an elliptic Calogero--Sutherland model


  A model describing N particles on a line interacting pairwise via an elliptic
function potential in the presence of an external field is partially solved in
the quantum case in a totally algebraic way. As an example, the ground state
and the lowest excitations are calculated explicitly for N=2.

</DOC>
<DOC>
<DOCNO> 84664 </DOCNO>
Self-similar perfect fluids


  Space-times admitting an $r$-parameter Lie group of homotheties are studied
for $r > 2$ devoting a special attention to those representing perfect fluid
solutions to Einstein's field equations.

</DOC>
<DOC>
<DOCNO> 13732 </DOCNO>
Stability of Attractive Bose-Einstein Condensates in a Periodic


  Using a standing light wave trap, a stable quasi-one-dimensional attractive
dilute-gas Bose-Einstein condensate can be realized. In a mean-field
approximation, this phenomenon is modeled by the cubic nonlinear Schr\"odinger
equation with attractive nonlinearity and an elliptic function potential of
which a standing light wave is a special case. New families of stationary
solutions are presented. Some of these solutions have neither an analog in the
linear Schr\"odinger equation nor in the integrable nonlinear Schr\"odinger
equation. Their stability is examined using analytic and numerical methods.
Trivial-phase solutions are experimentally stable provided they have nodes and
their density is localized in the troughs of the potential. Stable
time-periodic solutions are also examined.

</DOC>
<DOC>
<DOCNO> 84479 </DOCNO>
Primordial fractal density perturbations and structure formation in the


  Two-point correlation function of galaxy distribution shows that the
structure in the present Universe is scale-free up to a certain scale (at least
several tens Mpc), which suggests that a fractal structure may exist. If small
primordial density fluctuations have a fractal structure, the present
fractal-like nonlinear structure below the horizon scale could be naturally
explained. We analyze the time evolution of fractal density perturbations in
Einstein-de Sitter universe, and study how the perturbation evolves and what
kind of nonlinear structure will come out. We assume a one-dimensional
collisionless sheet model with initial Cantor-type fractal perturbations. The
nonlinear structure seems to approach some attractor with a unique fractal
dimension, which is independent of the fractal dimensions of initial
perturbations. A discrete self-similarity in the phase space is also found when
the universal nonlinear fractal structure is reached.

</DOC>
<DOC>
<DOCNO> 69169 </DOCNO>
Pion electroproduction on the nucleon and the generalized GDH sum rule


  Results of the recently developed unitary isobar model (MAID) are presented
for the spin asymmetries, structure functions and relevant sum rules in the
resonance region. The model describes the presently available data for
single-pion photo- and electroproduction in the resonance region below Wcm = 2
GeV very well. It is based on Born terms and resonance contributions, and the
respective multipoles are constructed in a gauge-invariant and unitary way for
each partial wave. The eta production is included in a similar way, while the
contribution of more-pion and higher channels is modeled by comparison with the
total cross sections and simple phenomenological assumptions. Our evaluation of
the energy-weighted integrals is in good agreement for the proton but shows big
discrepancies for the neutron.

</DOC>
<DOC>
<DOCNO> 8120 </DOCNO>
Equilibrium and nonequilibrium fluctuations at the interface between two


  We have performed small-angle light-scattering measurements of the static
structure factor of a critical binary mixture undergoing diffusive partial
remixing. An uncommon scattering geometry integrates the structure factor over
the sample thickness, allowing different regions of the concentration profile
to be probed simultaneously. Our experiment shows the existence of interface
capillary waves throughout the macroscopic evolution to an equilibrium
interface, and allows to derive the time evolution of surface tension.
Interfacial properties are shown to attain their equilibrium values quickly
compared to the system's macroscopic equilibration time.

</DOC>
<DOC>
<DOCNO> 13675 </DOCNO>
Aging dynamics and density relaxation in granular compaction


  We present an analytical approach to the out of equilibrium dynamics of a
class of kinetic lattice gases under gravity. The location of the jamming
transition, the critical exponents, and the scaling functions characterizing
the relaxation processes are determined. In particular, we find that
logarithmic compaction and simple aging are intimately related to the
Vogel-Fulcher law, while power-law compaction and super-aging behavior occur in
presence of a power-law diffusion.

</DOC>
<DOC>
<DOCNO> 102441 </DOCNO>
Base change and Grothendieck duality for Cohen-Macaulay maps


  Let $f:X\to Y$ be a Cohen-Macaulay map of finite type between Noetherian
schemes, and $:Y'\to Y$ a base change map, with $Y'$ Noetherian. Let $f'$ be
the base change of $f$ under $g$ and $g'$ the base change of $g$ under $f$. We
show that there is a canonical isomorphism between ${g'}^*\omega_f$ and
$\omega_{f'}$, where $\omega_f$ and $\omega_{f'}$ are the relative dualizing
sheaves. The map underlying this isomorphism is easily described when $f$ is
proper, and has subtler description when $f$ is not. If $f$ is smooth we show
that this map between the dualizing sheaves corresponds to the canonical
identification of differential forms. Our results generalize the results of B.
Conrad in two directions - wedo not need the properness assumption, and we do
not need to assume that theschemes involved carry dualizing complexes. Residual
complexes do not appear in this paper.

</DOC>
<DOC>
<DOCNO> 68507 </DOCNO>
Massive Spin 3/2 Electrodynamics


  We study the general non-minimally coupled charged massive spin 3/2 model
both for its low energy phenomenological properties and for its unitarity,
causality and degrees of freedom behaviour. When the model is viewed as an
effective theory, its parameters (after ensuring the correct excitation count)
are related to physical characteristics, such as the magnetic moment g factor,
by means of low energy theorems. We also provide the corresponding higher spin
generalisation. Separately, we consider both low and high energy unitarity, as
well as the causality aspects of our models. None (including truncated N=2
supergravity) is free of the minimal model's acausality.

</DOC>
<DOC>
<DOCNO> 40518 </DOCNO>
X Ray Precursors in GRBs and SGRs: outer X tails around a Precessing


  Weak isolated X-ray precursor events before the main Gamma Ray Burst, GRB,
and also rare Soft Gamma Repeaters, SGR, events are in disagreement with any
Fireball, or Magnetar, scenarios.
  These models are originated by an unique explosive event leading, by
internal-external shock waves, to softer secondary trains following a main
gamma signals. Indeed the earliest GRB980519,GRB981226 events as well as the
latest and most distant identified one as GRB000131 are showing rare but well
identified and distinct X Ray precursor, occurring tens of seconds or even a
minute before the main GRB eruption. These weak X precursors bursts correspond
to non-negligible energy powers, up to million Supernova ones.
  They are rare, about (3-6)% of all GRBs, but not unique.
  Similar huge explosive precursor are in total disagreement with a successive
main Fireball GRB outburst.
  Comparable brief X-ray precursor flashes are found also in rarest and most
detailed SGRs events as those observed on 27 and 29 August 1999 from SGR
1900+14.
  They are inconsistent with a Magnetar Fireball explosion.
  We interpret them as earlier marginal blazing of outlying X conical Jet tails
surrounding a narrower gamma precessing,spinning beamed Jet in blazing mode
toward the Earth; later re-crossing and better hitting of the target -the
satellite detectors- is source of the main GRB (and SGR) observed structured
event.
  The X Ray precursor existence is an additional remarkable evidence of the
Precessing relativistic Jet Nature of both GRBs and SGRs.

</DOC>
<DOC>
<DOCNO> 117638 </DOCNO>
Identifying the Reionization Redshift from the Cosmic Star Formation


  We show that the cosmic star formation rate per comoving volume should
exhibit a distinct drop around the reionization redshift, when the HII regions
in the intergalactic medium around individual ionizing sources first
overlapped. The drop results from the increase in the temperature of the
intergalactic medium as it was photo-ionized, and the consequent suppression of
the formation of low-mass galaxies. We show quantitatively that the detection
of this drop, which is marked by a corresponding fall in the number counts of
faint galaxies, should become feasible over the coming decade with the Next
Generation Space Telescope.

</DOC>
<DOC>
<DOCNO> 69388 </DOCNO>
Fermion Loops, conserved currents and single-W


  The relevance of fermion loop corrections to four fermion processes at e+ e-
colliders is reviewed with regard to the recent extension to the case of
massive external particles and its application to single-W processes.

</DOC>
<DOC>
<DOCNO> 68101 </DOCNO>
Neutrino Tests of General and Special Relativity


  We review the status of testing the principle of equivalence and Lorentz
invariance from atmospheric and solar neutrino experiments.

</DOC>
<DOC>
<DOCNO> 101314 </DOCNO>
Counting Isolated Roots of Trinomial Systems in the Plane and Beyond


  We prove that any pair of bivariate trinomials has at most 5 isolated roots
in the positive quadrant. The best previous upper bounds independent of the
polynomial degrees counted only non-degenerate roots and even then gave much
larger bounds, e.g., 248832 via a famous general result of Khovanski. Our bound
is sharp, allows real exponents, and extends to certain systems of n-variate
fewnomials, giving improvements over earlier bounds by a factor exponential in
the number of monomials. We also derive new bounds on the number of real
connected components of fewnomial hypersurfaces.

</DOC>
<DOC>
<DOCNO> 8753 </DOCNO>
Exact solution of generalized Schulz-Shastry type models


  A class of integrable one-dimensional models presented by Shastry and Schulz
is consequently extended to the whole class of one-dimensional Hubbard- or
XXZ-type models with correlated gauge-like hopping. A complete characterization
concerning solvability by coordinate Bethe ansatz of this class of models is
found.

</DOC>
<DOC>
<DOCNO> 178998 </DOCNO>
Chiral symmetry and quantum hadro-dynamics


  Using the linear sigma model, we study the evolutions of the quark condensate
and of the nucleon mass in the nuclear medium. Our formulation of the model
allows the inclusion of both pion and scalar-isoscalar degrees of freedom. It
guarantees that the low energy theorems and the constrains of chiral
perturbation theory are respected. We show how this formalism incorporates
quantum hadro-dynamics improved by the pion loops effects.

</DOC>
<DOC>
<DOCNO> 120412 </DOCNO>
Coordinated Monitoring of the Eccentric O-star Binary Iota Orionis: The


  We analyse two ASCA observations of the highly eccentric O9III + B1III binary
Iota Orionis obtained at periastron and apastron. Based on the assumption of a
strong colliding winds shock between the stellar components, we expected to see
significant variation in the X-ray emission between these phases. The
observations proved otherwise: the X-ray luminosities and spectral
distributions were remarkably similar. The only noteworthy feature was the hint
of a proximity effect during periastron passage, supported also in the optical.
We discuss the accuracy of our results, and also analyse archival ROSAT
observations. We investigate why we do not see a clear colliding winds
signature. A simple model shows that the wind attenuation to the expected
position of the shock apex is negligible throughout the orbit, which poses the
puzzling question of why the expected 1/D variation (ie. a factor of 7.5) in
the intrinsic luminosity is not seen in the data. Two scenarios are proposed:
either the colliding winds emission is unexpectedly weak such that intrinsic
shocks in the winds dominate the emission, or, alternatively, that the emission
observed is colliding winds emission but in a more complex form than we would
naively expect. Complex hydrodynamical models are then analyzed. Despite
strongly phase-variable emission from the models, both were consistent with the
observations. We find that if the mass-loss rates of the stars are low then
intrinsic wind shocks could dominate the emission. However, when we assume
higher mass-loss rates of the stars, we find that the observed emission could
also be consistent with a purely colliding winds origin. To distinguish between
the different models X-ray observations with improved phase coverage will be
necessary.

</DOC>
<DOC>
<DOCNO> 151887 </DOCNO>
QED_{2+1}: Compton effect on Dirac-Landau electrons


  Planar Quantum Electrodynamics is developed when charged fermions are under
the influence of a constant and homogeneous external magnetic field. We compute
the cross-length for the scattering of optical/ultraviolet photons by
Dirac-Landau electrons.

</DOC>
<DOC>
<DOCNO> 40116 </DOCNO>
Observation of the Omega_c Charmed Baryon at CLEO


  The CLEO detector at the CESR collider has used 13.7 fb^{-1} to search for
the production of Omega_c (css-ground state) in e^{+}e^{-} collisions at
sqrt{s} = 10.6 GeV The modes used to study the Omega_c are Omega- pi+, Omega-
pi+ pi0, Xi- K- pi+ pi+, Xi0 K- pi+, and Omega- pi+ pi+ pi-. We observe 40.4 +-
9.0(stat) combined events at a mass of 2694.6 +- 2.6(stat) +- 2.4(syst) MeV. We
have also measured the \sigma * Br of the above modes for xp > 0.5 to be 11.3
+- 3.9 +- 2.3 fb, 47.6 +- 18.0 +- 2.8 fb, 45.1 +- 23.2 +- 4.1 fb, 18.2 +- 10.6
+- 3.8 fb, and <5.1 fb @ 90 % CL, respectively.

</DOC>
<DOC>
<DOCNO> 99424 </DOCNO>
Vanishing Theorems on Toric Varieties


  We use Cox's description for sheaves on toric varieties and results about the
local cohomology with respect to monomial ideals to give a characteristic free
approach to vanishing results on arbitrary toric varieties. As an application,
we give a proof of a strong form of Fujita's conjecture in the case of toric
varieties. We also prove that every sheaf on a toric variety corresponds to a
module over the homogeneous coordinate ring, generalizing Cox's result for the
simplicial case.

</DOC>
<DOC>
<DOCNO> 12309 </DOCNO>
Dynamic Scaling in Diluted Systems Phase Transitions: Deactivation


  Activated scaling is confirmed to hold in transverse field induced phase
transitions of randomly diluted Ising systems. Quantum Monte Carlo calculations
have been made not just at the percolation threshold but well bellow and above
it including the Griffiths-McCoy phase. A novel deactivation phenomena in the
Griffiths-McCoy phase is observed using a thermal (in contrast to random)
dilution of the system.

</DOC>
<DOC>
<DOCNO> 121478 </DOCNO>
Constraining cosmological parameters with the clustering properties of


  (abridged) We use a theoretical model to predict the clustering properties of
galaxy clusters. Our technique accounts for past light-cone effects on the
observed clustering and follows the non-linear evolution of the dark matter
correlation function and cluster bias factor. A linear treatment of
redshift-space distortions is also included. We perform a maximum-likelihood
analysis by comparing the theoretical predictions to a set of observational
data, both in the optical (APM and EDCC catalogues) and X-ray band (RASS1
Bright Sample, BCS, XBACs, REFLEX). In the framework of CDM models, we compute
the constraints on cosmological parameters. Our results show that X-ray data
are more powerful than optical ones, allowing smaller regions in the parameter
space. We find that the clustering properties of clusters are almost
independent of the matter density parameter and of the presence of a
cosmological constant, while they appear to be strongly dependent on the shape
parameter. Using the X-ray data only, we obtain Gamma~0.1 and 0.4<sigma_8<1.1
for the Einstein-de Sitter model, while 0.14<Gamma<0.22 and 0.6<sigma_8<1.3 for
open and flat models with Omega_0m=0.3. Finally, we use our model to make
predictions on the correlation length of galaxy clusters expected in future
surveys. In particular, we show the results for an optical catalogue with
characteristics similar to the EIS project and for a very deep X-ray catalogue
with the characteristics of the XMM/LSS survey. We find that clusters at high
redshifts are expected to have larger a correlation length than local ones.

</DOC>
<DOC>
<DOCNO> 116396 </DOCNO>
Stationarity + wall jitter = Planck: The correct thermodynamics of


  I show that the wall jitter, which is classically necessary and sufficient
for the thermalisation of radiation, is also sufficient for the complete
thermodynamic analysis and derivation of Planck's law. The jitter is real and
comparable to the wavelengths involved, and continually modifies the very
structure of the stationary modes, questioning the validity of current
assumptions; I show that Planck's postulates are functionally equivalent to
ignoring the jitter. I also show that Landauer's principle is necessary and
sufficient to extend the picture to interactions with matter, identifying
quantum information with the observer's physical data states, and quantum
randomness with their thermalisation.

</DOC>
<DOC>
<DOCNO> 101015 </DOCNO>
Higher rank graph C*-algebras


  Building on recent work of Robertson and Steger, we associate a C*-algebra to
a combinatorial object which may be thought of as a higher rank graph. This
C*-algebra is shown to be isomorphic to that of the associated path groupoid.
Sufficient conditions on the higher rank graph are found for the associated
C*-algebra to be simple, purely infinite and AF. Results concerning the
structure of crossed products by certain natural actions of discrete groups are
obtained; a technique for constructing rank 2 graphs from ``commuting'' rank 1
graphs is given.

</DOC>
<DOC>
<DOCNO> 84151 </DOCNO>
A Metric Theory of Gravity with Condensed Matter Interpretation


  We consider a classical condensed matter theory in a Newtonian framework
where conservation laws
  \partial_t \rho + \partial_i (\rho v^i) = 0 
  \partial_t (\rho v^j) + \partial_i(\rho v^i v^j + p^{ij}) = 0
  are related with the Lagrange formalism in a natural way. For an ``effective
Lorentz metric'' g_{\mu\nu} it is equivalent to a metric theory of gravity
close to general relativity with Lagrangian
  L = L_{GR}
  - (8\pi G)^{-1}(\Upsilon g^{00}-\Xi (g^{11}+g^{22}+g^{33}))\sqrt{-g}
  We consider the differences between this theory and general relativity (no
nontrivial topologies, stable frozen stars instead of black holes, big bounce
instead of big bang singularity, a dark matter term), quantum gravity, and the
connection with realism and Bohmian mechanics.

</DOC>
<DOC>
<DOCNO> 70765 </DOCNO>
Determination of the pion-nucleon coupling constant and scattering


  We critically evaluate the isovector GMO sum rule for forward pion-nucleon
scattering using the recent precision measurements of negatively charged
pion-proton and pion-deuteron scattering lengths from pionic atoms. We deduce
the charged-pion-nucleon coupling constant, with careful attention to
systematic and statistical uncertainties. This determination gives, directly
from data a pseudoscalar coupling constant of
14.11+-0.05(statistical)+-0.19(systematic) or a pseudovector one of 0.0783(11).
This value is intermediate between that of indirect methods and the direct
determination from backward neutron-proton differential scattering cross
sections. We also use the pionic atom data to deduce the coherent symmetric and
antisymmetric sums of the negatively charged pion-proton and pion-neutron
scattering lengths with high precision. The symmetric sum gives
0.0012+-0.0002(statistical)+-0.0008 (systematic) and the antisymmetric one
0.0895+-0.0003(statistical)+-0.0013(systematic), both in units of inverse
charged pion-mass. For the need of the present analysis, we improve the
theoretical description of the pion-deuteron scattering length.

</DOC>
<DOC>
<DOCNO> 70419 </DOCNO>
Top quark mass definition and top quark pair production near threshold


  We suggest an infrared-insensitive quark mass, defined by subtracting the
soft part of the quark self energy from the pole mass. We demonstrate the deep
relation of this definition with the static quark-antiquark potential. At
leading order in 1/m this mass coincides with the PS mass which is defined in a
completely different manner. Going beyond static limit, the small normalization
point introduces recoil corrections which are calculated here as well. Using
this mass concept and other concepts for the quark mass we calculate the cross
section of e+ e- -> t t-bar near threshold at NNLO accuracy adopting three
alternative approaches, namely (1) fixing the pole mass, (2) fixing the PS
mass, and (3) fixing the new mass which we call the PS-bar mass. We demonstrate
that perturbative predictions for the cross section become much more stable if
we use the PS or the PS-bar mass for the calculations. A careful analysis
suggests that the top quark mass can be extracted from a threshold scan at NLC
with an accuracy of about 100-200 MeV.

</DOC>
<DOC>
<DOCNO> 40358 </DOCNO>
PIN Photodiodes for Radiation Monitoring and Protection in the BaBar


  We discuss the design, implementation and performance of the radiation
monitoring and protection system used by the Silicon Vertex Tracker (SVT) in
the BaBar detector. Using 12 reverse-biased PIN photodiodes mounted around the
beampipe near the IP, we are able to provide instantaneous radiation dose
rates, absorbed dose integrals, and active protection that aborts the
circulating beams in the PEP-II storage ring when radiation levels exceed
user-defined thresholds. The system has reliably protected the SVT from
excessive radiation damage and has also served as a key diagnostic tool in
understanding radiation backgrounds at PEP-II.

</DOC>
<DOC>
<DOCNO> 13234 </DOCNO>
Monte Carlo simulation of abnormal grain growth in two dimensions


  Abnormal grain growth in the presence of second phase particles is
investigated with the help of a two-dimensional Monte Carlo simulation. An
aggregate of equiaxed grains is considered with constant grain boundary energy
and mobility. The only driving force accounted for stems from the grain
boundary curvature. The process of abnormal grain growth is investigated as a
function of two governing parameters, the initial degree of pinning of the
matrix grains by the particles and the initial size advantage of the anomalous
grain. In such conditions, moderate growth is obtained whose specific features
are discussed with respect to the available models. It is shown that it is
possible to obtain drastic grain growth by introducing the thermally activated
unpinning of grain boundaries from particles. For this purpose, a simplified
but effective procedure is proposed and discussed that includes the influence
of the capillary force on the height of the local energy barrier for grain
unpinning.

</DOC>
<DOC>
<DOCNO> 84079 </DOCNO>
Flattening modulus of a neutron star by rotation and magnetic field


  We calculated the ellipticity of the deformed star due to the rotation or
magnetic field. These two effects are compared to each other within general
relativity. It turned out that the magnetic distortion is important for
recently observed candidates of magnetars, while the magnetic effect can be
neglected for well-known typical pulsars.

</DOC>
<DOC>
<DOCNO> 8662 </DOCNO>
Landau Theory of the Finite Temperature Mott Transition


  In the context of the dynamical mean-field theory of the Hubbard model, we
identify microscopically an order parameter for the finite temperature Mott
endpoint. We derive a Landau functional of the order parameter. We then use the
order parameter theory to elucidate the singular behavior of various physical
quantities which are experimentally accessible.

</DOC>
<DOC>
<DOCNO> 85303 </DOCNO>
Spin(7) holonomy manifold and Superconnection


  We discuss the higher dimensional generalization of gravitational instantons
by using volume-preserving vector fields. We give special attention to the case
of 8-dimensions and present a new construction of the Ricci flat metric with
holonomy in Spin(7). An example of the metric is explicitly given. Further it
is shown that our formulation has a natural interpretation in the Chern-Simons
theory written by the language of superconnections.

</DOC>
<DOC>
<DOCNO> 117851 </DOCNO>
On the inverse Compton scattering model of radio pulsars


  Some characteristics of the inverse Compton scattering (ICS) model are
reviewed. At least the following properties of radio pulsars can be reproduced
in the model: core or central emission beam, one or two hollow emission cones,
different emission heights of these components, diverse pulse profiles at
various frequencies, linear and circular polarization features of core and
cones.

</DOC>
<DOC>
<DOCNO> 8169 </DOCNO>
Nuclear Spin Qubit Dephasing Time in the Integer Quantum Hall Effect


  We report the first theoretical estimate of the nuclear-spin dephasing time
T_2 owing to the spin interaction with the two-dimensional electron gas, when
the latter is in the integer quantum Hall state, in a two-dimensional
heterojunction or quantum well at low temperature and in large applied magnetic
field. We establish that the leading mechanism of dephasing is due to the
impurity potentials that influence the dynamics of the spin via virtual
magnetic spin-exciton scattering. Implications of our results for
implementation of nuclear spins as quantum bits (qubits) for quantum computing
are discussed.

</DOC>
<DOC>
<DOCNO> 9997 </DOCNO>
Fluctuation and relaxation properties of pulled fronts: a possible


  We argue that while fluctuating fronts propagating into an unstable state
should be in the standard KPZ universality class when they are {\em pushed},
they should not when they are {\em pulled}: The universal $1/t$ velocity
relaxation of deterministic pulled fronts makes it unlikely that the KPZ
equation is the appropriate effective long-wavelength low-frequency theory in
this regime. Simulations in 2$D$ confirm the proposed scenario, and yield
exponents $\beta \approx 0.29\pm 0.01$, $\zeta \approx 0.40\pm 0.02$ for
fluctuating pulled fronts, instead of the KPZ values $\beta=1/3$, $\zeta =
1/2$. Our value of $\beta$ is consistent with an earlier result of Riordan {\em
et al.}

</DOC>
<DOC>
<DOCNO> 71592 </DOCNO>
Theory of pi pi scattering


  I describe the current status of the theory of pi pi scattering, reviewing in
particular recent work on the numerical solution of Roy equations and on the
matching between these and the chiral representation. I discuss numerical
results on the scattering lengths and other threshold parameters.

</DOC>
<DOC>
<DOCNO> 120293 </DOCNO>
Evolutionary tracks and isochrones for alpha-enhanced stars


  We present four large sets of evolutionary tracks for stars with initial
chemical compositions [Y=0.250, Z=0.008], [Y=0.273, Z=0.019], [Y=0.320,
Z=0.040] and [Y=0.390, Z=0.070] and enhancement of alpha elements with respect
to the solar pattern. The major improvement with respect to previous similar
calculations is that we use consistent opacities - i.e. computed with the same
chemical composition as adopted in the stellar models - over the whole relevant
range of temperatures. For the same initial chemical compositions [Y,Z] and
otherwise identical input physics we present also new evolutionary sequences
with solar-scaled mixtures of abundances. Based on these stellar models we
calculate the corresponding sets of isochrones both in the Johnson-Cousins
UBVRIJHK and HST/WFPC2 photometric systems. Furthermore, we derive integrated
magnitudes, colours and mass-to-light ratios for ideal single stellar
populations with total mass equal to 1 Msun. Finally, the major changes in the
tracks, isochrones, and integrated magnitudes and colours passing from
solar-scaled to alpha-enhanced mixtures are briefly outlined. Retrieval of the
complete data set is possible via http://pleiadi.pd.astro.it .

</DOC>
<DOC>
<DOCNO> 117750 </DOCNO>
Estimating reaction rates and uncertainties for primordial


  We present a Monte Carlo method for direct incorporation of nuclear inputs in
primordial nucleosynthesis calculations. This method is intended to remedy
shortcomings of current error estimation, by eliminating intermediate data
evaluations and working directly with experimental data, allowing error
estimation based solely on published experimental uncertainties. This technique
also allows simple incorporation of new data and reduction of errors with the
introduction of more precise data. Application of our method indicates that
previous error estimates on the calculated abundances were too large by as much
as a factor of three. Since uncertainties in the BBN calculation currently
dominate inferences drawn from light-element abundances, the re-estimated
errors have important consequences for cosmic baryon density, neutrino physics,
and lithium depletion in halo stars. Our direct method allows detailed
discussion of the status of the nuclear inputs, by identifying clearly the
places where improved cross section measurements would be most useful.

</DOC>
<DOC>
<DOCNO> 13101 </DOCNO>
Fermi Surface and Spectral Functions of a Hole Doped Spin-Fermion Model


  Using numerical techniques we study the spectral function $A(k,\omega)$ of a
spin-fermion model for cuprates in the regime where magnetic and charge domains
(stripes) are developed upon hole-doping. From $A(k,\omega)$ we study the
electronic dynamics and determine the Fermi Surface (FS), which is compared
with angular resolved photoemission results for $La_{2-x}Sr_xCuO_2$. A
pseudogap is observed in the density of states at the chemical potential for
all finite dopings. The striped ground state appears to be metallic in this
model since there is finite spectral weight at the chemical potential, but the
electronic hopping seems to be stronger perpendicular to the stripes rather
than along them. The band structure is not rigid, contrary to the behavior
found in mean-field studies, and changes with doping. Both mid-gap (stripe
induced) and valence band states determine the FS. For vertical (horizontal)
stripes, a clear FS appears close to $(\pi,0)$ $((0,\pi))$, while no FS is
observed close to $(0,\pi)$ $((\pi,0))$. Along the diagonal direction the
spectral function shows a clear quasi-particle peak close to (0,0), but its
weight is reduced as the chemical potential is approached. A weak FS develops
along this direction as the system is doped.

</DOC>
<DOC>
<DOCNO> 118608 </DOCNO>
On the Disappearance of Kilohertz Quasi-Periodic Oscillations at a High


  For all sources in which the phenomenon of kilo-Hertz quasi-periodic
oscillation (kHz QPO) is observed, the QPOs disappear abruptly when the
inferred mass accretion rate exceeds a certain threshold. Although the
threshold cannot at present be accurately determined (or even quantified)
observationally, it is clearly higher for bright Z sources than for faint atoll
sources. Here we propose that the observational manifestation of kHz QPOs {\em
requires} direct interaction between the neutron star magnetosphere and the
Keplerian accretion disk and that the cessation of kHz QPOs at high accretion
rate is due to the lack of such an interact when the Keplerian disk terminates
at the last stable orbit and yet the magnetosphere is pushed farther inward.
The threshold is therefore dependent of the magnetic field strength -- the
stronger the magnetic field the higher the threshold. This is certainly in
agreement with the atoll/Z paradigm, but we argue that it is also generally
true, even for individual sources within each (atoll or Z) category. For atoll
sources, the kHz QPOs also seem to vanish at low accretion rate. Perhaps the
``disengagement'' between the magnetosphere and the Keplerian disk also takes
place under such circumstances, because of, for instance, the presence of
quasi-spherical advection-dominated accretion flow (ADAF) close to the neutron
star. Unfortunately, in this case, the estimation of the accretion rate
threshold would require a knowledge of the physical mechanisms that cause the
disengagement. If the ADAF is responsible, the threshold is likely dependent of
the magnetic field of the neutron star.

</DOC>
<DOC>
<DOCNO> 13146 </DOCNO>
Optimal design and quantum limit for second harmonic generation in


  The optimal design for infrared second harmonic generation (SHG) is
determined for a GaAs-based quantum device using a recently developed genetic
approach. Both compositional parameters and electric field are simultaneously
optimized, and the quantum limit for SHG, set by the trade-off between large
dipole moments (favouring electron delocalization) and large overlaps
(favouring electron localization), is determined. Optimal devices are generally
obtained with an asymmetric double quantum well shape with narrow barriers and
a graded region sideways to the largest well. An electric field is not found to
lead to improved SHG if compositional parameters are optimized.

</DOC>
<DOC>
<DOCNO> 40378 </DOCNO>
Measurement of Charmed Meson Lifetimes with Belle


  The lifetimes of charmed mesons have been measured using 2.75fb$^{-1}$ of
data collected with the Belle detector at KEKB. Each candidate is fully
reconstructed to identify the flavor of the charmed meson. The lifetimes are
measured to be $\tau(D^0)=(414.8\pm3.8\pm3.4)$ fs,
$\tau(D^+)=(1040^{+23}_{-22}\pm18)$ fs and
$\tau(D_s^+)=(479^{+17}_{-16}{}^{+6}_{-8})$ fs, where the first error is
statistical and the second error is systematic. The mixing parameter $y_{CP}$
is also measured through the lifetime difference of $D^0$ mesons decaying into
CP-mixed states and CP eigenstates. We find
$y_{CP}=(1.0^{+3.8}_{-3.5}{}^{+1.1}_{-2.1})%$, corresponding to a 95%
confidence interval $-7.0%<\ycp<8.7%$.

</DOC>
<DOC>
<DOCNO> 152255 </DOCNO>
Stringy Higgs Mechanism and the Fate of Open Strings


  We propose a refinement of the physical picture describing different vacua in
bosonic string theory. The vacua with closed strings and open strings are
connected by the string field theory version of the Higgs mechanism,
generalizing the Higgs mechanism of an abelian gauge field interacting with a
complex scalar. In accordance with Sen's conjecture, the condensation of the
tachyon is an essential part of the story. We consider this phenomenon from the
point of view of both a world-sheet sigma-model and the target-space theory. In
the Appendix the relevant remarks regarding the choice of the coordinates in
the background independent open string field theory are given.

</DOC>
<DOC>
<DOCNO> 68974 </DOCNO>
Pertinent Dirac structure for QCD sum rules of meson-baryon coupling


  Using general baryon interpolating fields $J_B$ for $B= N, \Xi, \Sigma, $
without derivative, we study QCD sum rules for meson-baryon couplings and their
dependence on Dirac structures for the two-point correlation function with a
meson $i\int d^4x e^{iqx} \bra 0|{\rm T}[J_B(x)\bar{J}_B(0)] |{\cal M}(p)\ket$.
Three distinct Dirac structures are compared: $i\gamma_5$,
$i\gamma_5\fslash{p}$, and $\gamma_5\sigma_{\mu\nu}q^\mu p^\nu$ structures.
  From the dependence of the OPE on general baryon interpolating fields, we
propose criteria for choosing an appropriate Dirac structure for the coupling
sum rules. The $\gamma_5\sigma_{\mu\nu}q^\mu p^\nu$ sum rules satisfy the
criteria while the $i\gamma_5$ sum rules beyond the chiral limit do not. For
the $i\gamma_5\fslash{p}$ sum rules, the large continuum contributions prohibit
reliable prediction for the couplings. Thus, the $\gamma_5\sigma_{\mu\nu}q^\mu
p^\nu$ structure seems pertinent for realistic predictions. In the SU(3) limit,
we identify the OPE terms responsible for the $F/D$ ratio. We then study the
dependence of the ratio on the baryon interpolating fields. We conclude the
ratio $F/D \sim 0.6-0.8$ for appropriate choice of the interpolating fields.

</DOC>
<DOC>
<DOCNO> 117462 </DOCNO>
CTQ 839: Candidate for the Smallest Projected Separation Binary Quasar


  We report the discovery of the new double quasar CTQ 839. This B = 18.3,
radio quiet quasar pair is separated by 2.1" in BRIH filters with magnitude
differences of delta m_B = 2.5, delta m_R = delta m_I = 1.9, and delta m_H =
2.3. Spectral observations reveal both components to be z = 2.24 quasars, with
relative redshifts that agree at the 100 km/s level, but exhibit pronounced
differences in the equivalent widths of related emission features, as well as
an enhancement of blue continuum flux in the brighter component longward of the
Ly alpha emission feature. In general, similar redshift double quasars can be
the result of a physical binary pair, or a single quasar multiply imaged by
gravitational lensing. Empirical PSF subtraction of R and H band images of CTQ
839 reveal no indication of a lensing galaxy, and place a detection limit of R
= 22.5 and H = 17.4 for a third component in the system. For an Einstein-de
Sitter cosmology and SIS model, the R band detection limit constrains the
characteristics of any lensing galaxy to z_lens >= 1 with a corresponding
luminosity of L >~ 5 L_*, while an analysis based on the redshift probability
distribution for the lensing galaxy argues against the existence of a z_lens >~
1 lens at the 2 sigma level. A similar analysis for a Lambda dominated
cosmology, however, does not significantly constrain the existence of any
lensing galaxy. The broadband flux differences, spectral dissimilarities, and
failure to detect a lensing galaxy make the lensing hypothesis for CTQ 839
unlikely. The similar redshifts of the two components would then argue for a
physical quasar binary. At a projected separation of 8.3/h kpc (Omega_matter =
1), CTQ 839 would be the smallest projected separation binary quasar currently
known.

</DOC>
<DOC>
<DOCNO> 151373 </DOCNO>
Correlation functions for M^N/S_N orbifolds


  We develop a method for computing correlation functions of twist operators in
the bosonic 2-d CFT arising from orbifolds M^N/S_N, where M is an arbitrary
manifold. The path integral with twist operators is replaced by a path integral
on a covering space with no operator insertions. Thus, even though the CFT is
defined on the sphere, the correlators are expressed in terms of partition
functions on Riemann surfaces with a finite range of genus g. For large N, this
genus expansion coincides with a 1/N expansion. The contribution from the
covering space of genus zero is `universal' in the sense that it depends only
on the central charge of the CFT. For 3-point functions we give an explicit
form for the contribution from the sphere, and for the 4-point function we do
an example which has genus zero and genus one contributions. The condition for
the genus zero contribution to the 3-point functions to be non--vanishing is
similar to the fusion rules for an SU(2) WZW model. We observe that the 3-point
coupling becomes small compared to its large N limit when the orders of the
twist operators become comparable to the square root of N - this is a
manifestation of the stringy exclusion principle.

</DOC>
<DOC>
<DOCNO> 102626 </DOCNO>
Solvable groups definable in o-minimal structures


  Let N be an o-minimal structure. In this paper we develop group extension and
group cohomology theory over N and use it to describe the N-definable solvable
groups. We prove an o-minimal analogue of the Lie-Kolchin-Mal'cev theorem and
we describe the N-definable G-modules and the N-definable rings.

</DOC>
<DOC>
<DOCNO> 116958 </DOCNO>
Overview of the Heavy Ion Fusion Program


  The world Heavy Ion Fusion (HIF) Program for inertial fusion energy is
looking toward the development and commissioning of several new experiments.
Recent and planned upgrades of the facilities at GSI, in Russia, and in Japan
greatly enhance the ability to study energy deposition in hot dense matter.
Worldwide target design developments have focused on non-ignition targets for
nearterm experiments and designs which, while lowering the energy required for
ignition, tighten accelerator requirements. The U.S program is transitioning
between scaled beam dynamics experiments and high current experiments with
power-plant-driver-scale beams. Current effort is aimed at preparation for the
next-step large facility, the Integrated Research Experiment (IRE)-- an
induction linac accelerating multiple beams to a few hundred MeV, then focusing
to deliver tens of kilojoules to a target. The goal is to study heavy ion
energy deposition, and to test all of the components and physics needed for an
engineering test of a power plant driver and target chamber. This paper will
include an overview of the Heavy Ion Fusion program abroad and a more in-depth
view of the progress and plans of the U.S. program.

</DOC>
<DOC>
<DOCNO> 170597 </DOCNO>
Semiclassical dressed states of two-level quantum systems driven by


  Analytical expressions for the semiclassical dressed states and corresponding
quasienergies are obtained for a two-level quantum system driven by a
nonresonant and/or strong laser field in a coherent state. These expressions
are of first order in a proper perturbative expansion, and already contain all
the relevant physical information on the dynamical and spectroscopic properties
displayed by these systems under such particular conditions. The influence of
the laser field parameters on transition frequencies, selection rules, and line
intensities can be easily understood in terms of the quasienergy-level diagram
and the allowed transitions between the different semiclassical dressed states.

</DOC>
<DOC>
<DOCNO> 122241 </DOCNO>
Detections of SiO and H$_2$O Masers in the Bipolar Nebula IRAS


  We report on the detection of SiO and water masers toward a newly found
bipolar nebula, IRAS 19312+1950. This object exhibits extreme red IRAS color
log (F25/F12)=0.5 and log (F60/F25)=0.7 and a nebulosity having a size of about
30" extended to the South-West in the 2MASS near-infrared image. Toward this
object, we have detected emission from the H2O 6(1,6)-5(2,3) transition, the
SiO J=1-0, v=1 and 2, and J=2-1, v=1 transitions, and the SO 2(2)--1(1) and
H13CN J=1-0 transitions. The thermal lines of SO and H13CN are shifted by about
12 km/s in radial velocity with respect to the maser lines, indicating that
thermal emission comes from the background molecular cloud. However, the SiO
J=2-1, v=2 spectrum shows another component of SiO emission separated by 26
km/s from the main component, that might be formed in a rotating or expanding
shell.

</DOC>
<DOC>
<DOCNO> 118603 </DOCNO>
ASCA Observations of the Absorption-Line Features from the Super-Luminal


  GRS1915+105 was observed with ASCA six times from 1994 to 1999. The source
was so bright that most SIS data suffered from event pileup. We have developed
a new technique to circumvent the pileup effect and carried out a
high-resolution spectroscopy. In the energy spectra of 1994 and 1995, resonant
absorption lines of Ca XX Ka, Fe XXV Ka, Fe XXVI Ka, as well as blends of the
absorption lines of Ni XXVII Ka + Fe XXV Kb and Ni XXVIII Ka + Fe XXVI Kb, were
observed. Such absorption lines have not been found in other objects, except
for iron absorptions lines from GRO J1655-40, another super-luminal jet source
(Ueda et al. 1998). We carried out a ``curve of growth'' analysis for the
absorption lines, and estimated column densities of the absorbing ions. We
found that a plasma of moderate temperature (0.1-10 keV) and cosmic abundance
cannot account for the observed large equivalent widths. The hydrogen column
density of such plasma would be so high that the optical depth of Thomson
scattering would be too thick (N_H >10^24 cm^-2). We require either a very high
kinetic temperature of the ions (> 100 keV) or extreme over-abundances (> 100
Z). In the former case, the ion column densities have reasonable values (<
10^18 cm^-2). We modeled the absorber as a photo-ionized disk which envelops
the central X-ray source. Using a photo-ionization calculation code, we
constrain physical parameters of the plasma disk, such as the ionization
parameter, radius, and density. Estimated parameters were found to be
consistent with those of a radiation-driven disk wind. These absorption-line
features may be peculiar to super-luminal jet sources and related to the jet
formation mechanism. Alternatively, they may be common characteristics of
super-critical edge-on systems.

</DOC>
<DOC>
<DOCNO> 150349 </DOCNO>
Gauge and Gravitational Couplings from Modular Orbits in Orbifold


  We discuss the appearance of modular functions at the one-loop gauge and
gravitational couplings in (0,2) non-decomposable N=1 four dimensional orbifold
compactifications of the heterotic string. We define the limits for the
existence of states causing singularities in the moduli space in the
perturbative regime for a generic vacuum of the heterotic string. The "proof"
provides evidence for the explanation of the stringy Higgs effect.

</DOC>
<DOC>
<DOCNO> 117415 </DOCNO>
X-ray observations of the high magnetic field radio pulsar PSR


  PSR J1814-1744 is a 4 s radio pulsar with surface dipole magnetic field
strength 5.5*10^13 G, inferred assuming simple magnetic dipole braking. This
pulsar's spin parameters are very similar to those of anomalous X-ray pulsars
(AXPs), suggesting that this may be a transition object between the radio
pulsar and AXP population, if AXPs are isolated, high magnetic field neutron
stars as has recently been hypothesized. We present archival X-ray observations
of PSR J1814-1744 made with ROSAT and ASCA. X-ray emission is not detected from
the position of the radio pulsar. The derived upper flux limit implies an X-ray
luminosity significantly smaller than those of all known AXPs. This conclusion
is insensitive to the possibility that X-ray emission from PSR J1814-1744 is
beamed or that it undergoes modest variability. When interpreted in the context
of the magnetar mechanism, these results argue that X-ray emission from AXPs
must depend on more than merely the inferred surface magnetic field strength.
This suggests distinct evolutionary paths for radio pulsars and AXP, despite
their proximity in period--period derivative phase space.

</DOC>
<DOC>
<DOCNO> 117737 </DOCNO>
Note on the Origin of the Highest Energy Cosmic Rays


  In this note we argue that the galactic model chosen by E.-J. Ahn, G.
Medina-Tanco, P.L. Bierman and T. Stanev in their paper discussing the origin
of the highest energy cosmic rays, is alone responsible for the focussing of
positive particles towards the North galactic pole. We discuss the validity of
this model, in particular in terms of field reversals and radial extensions. We
conclude that with such a model one cannot retreive any directional information
from the observed direction of the cosmic rays. In particular one cannot
identify point sources at least up to energies of about 200 EeV. Therefore the
apparent clustering of the back-traced highest energy cosmic rays observed to
date cannot be interpreted as an evidence for a point source nor for the
identification of M87, which happens to be close to the North pole, as being
such a source.

</DOC>
<DOC>
<DOCNO> 67876 </DOCNO>
Description of local multiplicity fluctuations and genuine multiparticle


  Various parametrizations of the multiplicity distribution are studied using
the recently published large statistics OPAL results on multidimensional local
fluctuations and genuine correlations in e+e- -> Z -> hadrons. The measured
normalized factorial and cumulant moments are compared to the predictions of
the negative binomial distribution, the modified and generalized versions of
it, the log-normal distribution and the model of the generalized birth process
with immigration. This is the first study which uses the multiplicity
distribution parametrizations to describe high-order genuine correlations.
Although the parametrizations fit well the measured fluctuations and
correlations for low orders, they do show certain deviations at high orders. We
have shown that it is necessary to incorporate the multiparticle character of
the correlations along with the property of self-similarity to attain a good
description of the measurements.

</DOC>
<DOC>
<DOCNO> 116267 </DOCNO>
Further Effects of Varying G


  The correct perihelion precession was recently deduced within the frame work
of a time varying Gravitational constant G. Here, we deduce also the observed
gravitational bending of light and flattening of galactic rotational curves.

</DOC>
<DOC>
<DOCNO> 102388 </DOCNO>
On the tautological ring of $\bar{M}_{g,n}$


  We prove that the dimension 0 part of the tautological ring of the moduli
space of stable pointed curves is one-dimensional. This provides the first
genus-free evidence for a conjecture of Faber and Pandharipande that the
tautological ring of the moduli space is Gorenstein, answering in the
affirmative a question of Hain and Looijenga.

</DOC>
<DOC>
<DOCNO> 117160 </DOCNO>
Is the Basic Unit System a String?


  The main aim of this paper is to present an overview of the need of a new way
of coping the fundamental equations of physics, see the references. Our main
aim is to build a new metrics in which both time and space are included, but in
some sort of minkowskian union of the two and in such a way that that union
preserves an independent reality, and where energy, can be taken as the real
fundamental issue of that metrics, instead of the particle concept. A departure
from General Theory of Relativity is clear, but then the BUS concept behaves
itself as a fundamental string.

</DOC>
<DOC>
<DOCNO> 71934 </DOCNO>
Kaon Physics with Light Sgoldstinos and Parity Conservation


  Superpartners of goldstino -- scalar and pseudoscalar sgoldstinos -- interact
weakly with ordinary particles. One or both of them may be light. We consider a
class of supersymmetric extensions of the Standard Model in which interactions
of sgoldstinos with quarks and gluons conserve parity but do not conserve quark
flavor. If the pseudoscalar sgoldstino $P$ is light, m_P<(m_K-2m_\pi), and the
scalar sgoldstino is heavier, m_S>(m_K-m_\pi), an interesting place for
experimental searches is the poorly explored area of three-body decays of
kaons, K^0_{S,L}\to\pi^+\pi^- P, K^0_{S,L}\to\pi^0\pi^0 P and K^+\to\pi^+\pi^0
P, with $P$ subsequently decaying into \gamma\gamma, possibly e^+e^-, or flying
away from the detector. We evaluate the constraints on the flavor-violating
coupling of sgoldstino to quarks which are imposed by K^0_L-K^0_S mass
difference and CP-violation in neutral kaon system, and find that these
constraints allow for fairly large Br(K\to\pi\pi P). We find that the most
interesting ranges of branching ratios start at Br(K^0_L\to\pi\pi P)\sim
10^{-3}, Br(K^+\to\pi^+\pi^0 P)\sim 10^{-4}, Br(K_S^0\to\pi\pi P)\sim 10^{-3}.
These searches for light pseudoscalar sgoldstino would be sensitive to the
supersymmetry breaking scale \sqrt{F} in the 100 TeV range and above. We also
briefly discuss the cases of light scalar sgoldstino and relatively heavy
sgoldstinos.

</DOC>
<DOC>
<DOCNO> 40261 </DOCNO>
Nucleon Transversity Distribution from Azimuthal Spin Asymmetry in Pion


  The azimuthal asymmetry observed by the HERMES collaboration in
semi-inclusive pion production in deep inelastic scattering of unpolarized
positron on the longitudinally polarized proton target, can provide information
of the quark transversity distributions of the nucleon. We show that the quark
transversity distributions predicted both by the light-cone
quark-spectator-diquark model and by a pQCD inspired model can give consistent
descriptions of the available HERMES data for the analyzing powers
$A_{UL}^{\sin \phi}$ and $A_{UL}^{\sin 2 \phi}$ for $\pi^+$ and $\pi^-$
productions. We also show that the two models give similar predictions of
$A_{UL}^{\sin \phi}$ for $\pi^+$ production, whereas they give very different
predictions of $A_{UL}^{\sin \phi}$ for $\pi^-$ production at large $x$.
Further precision measurement of $A_{UL}^{\sin \phi}$ for $\pi^-$ production
can provide a decisive test of different models.

</DOC>
<DOC>
<DOCNO> 9378 </DOCNO>
Temperature dependence of the spin polarization in the fractional


  Using a Hamiltonian formulation of Composite Fermions that I recently
developed with R. Shankar, I compute the dependence of the spin polarization on
the temperature for the translationally invariant fractional quantum Hall
states at $\nu=1/3$ and $\nu=2/5$. I compare my results to experiments at
$\nu=1/3$ and find reasonably good agreement.

</DOC>
<DOC>
<DOCNO> 12845 </DOCNO>
Quantum critical behavior in disordered itinerant ferromagnets:


  The quantum critical behavior of disordered itinerant ferromagnets is
determined exactly by solving a recently developed effective field theory. It
is shown that there are logarithmic corrections to a previous calculation of
the critical behavior, and that the exact critical behavior coincides with that
found earlier for a phase transition of undetermined nature in disordered
interacting electron systems. This confirms a previous suggestion that the
unspecified transition should be identified with the ferromagnetic transition.
The behavior of the conductivity, the tunneling density of states, and the
phase and quasiparticle relaxation rates across the ferromagnetic transition is
also calculated.

</DOC>
<DOC>
<DOCNO> 99714 </DOCNO>
Gerbes on complex reductive Lie groups


  We construct a gerbe over a complex reductive Lie group G attached to an
invariant bilinear form on a maximal diagonalizable subalgebra which is Weyl
group invariant and satisfies a parity condition. By restriction to a maximal
compact subgroup K, one then gets a gerbe over K. For a simply-connected group,
the parity condition is the same used by Pressley and Segal; in general, it was
introduced by Deligne and the author. The gerbe is defined by geometric
methods, using the so-called Grothendieck manifold. It is equivariant under the
conjugation action of G; its restriction to a semisimple orbit is not always
trivial. The paper starts with a discussion of gerbe data (in the sense of
Chatterjee and Hitchin) and of gerbes as geometric objects (sheaves of
groupoids); the relation between the two approaches is presented. There is an
Appendix on equivariant gerbes, discussed from both points of view.

</DOC>
<DOC>
<DOCNO> 69784 </DOCNO>
Muon Bremsstrahlung and Muonic Pair Production in Air Showers


  The objective of this work is to report on the modifications in air shower
development due to muon bremsstrahlung and muonic pair production. In order to
do that we have implemented new muon bremsstrahlung and muonic pair production
procedures in the AIRES air shower simulation system, and have used it to
simulate ultra high energy showers in different conditions.
  The influence of the mentioned processes in the global development of the air
shower is important for primary particles of large zenith angles, while they do
not introduce significant changes in the position of the shower maximum.

</DOC>
<DOC>
<DOCNO> 118717 </DOCNO>
Chandra X-ray Observatory Arcsecond Imaging of the Young, Oxygen-rich


  We present observations of the young, Oxygen-rich supernova remnant
1E0102.2-7219 taken by the Chandra X-ray Observatory during Chandra's Orbital
Activation and Checkout phase. The boundary of the blast wave shock is clearly
seen for the first time, allowing the diameter of the remnant and the mean
blast wave velocity to be determined accurately. The prominent X-ray bright
ring of material may be the result of the reverse shock encountering ejecta;
the radial variation of O VII vs. O VIII emission indicates an ionizing shock
propagating inwards, possibly through a strong density gradient in the ejecta.
We compare the X-ray emission to Australia Telescope Compact Array 6 cm radio
observations (Amy and Ball) and to archival Hubble Space Telescope [O III]
observations. The ring of radio emission is predominantly inward of the outer
blast wave, consistent with an interpretation as synchrotron radiation
originating behind the blast wave, but outward of the bright X-ray ring of
emission. Many (but not all) of the prominent optical filaments are seen to
correspond to X-ray bright regions. We obtain an upper limit of ~9e33 erg/s (3
sigma) on any potential pulsar X-ray emission from the central region.

</DOC>
<DOC>
<DOCNO> 116243 </DOCNO>
Simple quantum systems in the momentum representation


  The momentum representation is seldom used in quantum mechanics courses. Some
students are thence surprised by the change in viewpoint when, in doing
advanced work, they have to use the momentum rather than the coordinate
representation. In this work, we give an introduction to quantum mechanics in
momentum space, where the Schr\"odinger equation becomes an integral equation.
To this end we discuss standard problems, namely, the free particle, the
quantum motion under a constant potential, a particle interacting with a
potential step, and the motion of a particle under a harmonic potential. What
is not so standard is that they are all conceived from momentum space and hence
they, with the exception of the free particle, are not equivalent to the
coordinate space ones with the same names. All the problems are solved within
the momentum representation making no reference to the systems they correspond
to in the coordinate representation.

</DOC>
<DOC>
<DOCNO> 150858 </DOCNO>
The many faces of OSp(1|32)


  We show that the complete superalgebra of symmetries, including central
charges, that underlies F-theories, M-theories and type II string theories in
dimensions 12, 11 and 10 of various signatures correspond to rewriting of the
same OSp(1|32) algebra in different covariant ways. One only has to distinguish
the complex and the unique real algebra. We develop a common framework to
discuss all signatures theories by starting from the complex form of OSp(1|32).
Theories are distinguished by the choice of basis for this algebra. We
formulate dimensional reductions and dualities as changes of basis of the
algebra. A second ingredient is the choice of a real form corresponding to a
specific signature. The existence of the real form of the algebra selects
preferred spacetime signatures. In particular, we show how the real d=10 IIA
and IIB superalgebras for various signatures are related by generalized
T-duality transformations that not only involve spacelike but also timelike
directions. A third essential ingredient is that the translation generator in
one theory plays the role of a central charge operator in the other theory. The
identification of the translation generator in these algebras leads to the star
algebras of Hull, which are characterized by the fact that the positive
definite energy operator is not part of the translation generators. We apply
our results to discuss different T-dual pictures of the D-instanton solution of
Euclidean IIB supergravity.

</DOC>
<DOC>
<DOCNO> 71359 </DOCNO>
Chiral Dynamics in the electroweak sector


  Using a chiral Lagrangian we show that strongly interacting models of
electroweak symmetry breaking are not in conflict with precision data. Such
models, like Technicolor, need not lead to a heavy Higgs-like signal.
Furthermore, the allowed values for the low-energy constants in the effective
Lagrangian, derived from bounds on the oblique correction parameters S,T,U, are
not unnatural. Finally, we point out that there are some problems with gauge
invariance, if one tries to relate the oblique parameters to the low-energy
constants in the ordinary chiral Lagrangian for QCD of Gasser and Leutwyler. In
particular, S cannot be identified with l_5^{GL}.

</DOC>
<DOC>
<DOCNO> 39911 </DOCNO>
Measurements of Charm Fragmentation into $D_s^{*+}$ and $D_s^+$ in


  A study of charm fragmentation into $D_s^{*+}$ and $D_s^+$ in $e^+e^-$
annihilations at $\sqrt{s}$=10.5 GeV is presented. This study using $4.72 \pm
0.05$ fb$^{-1}$ of CLEO II data reports measurements of the cross-sections
$\sigma(D_s^{*+})$ and $\sigma(D_s^+)$ in momentum regions above $x=0.44$,
where $x$ is the $D_s$ momentum divided by the maximum kinematically allowed
$D_s$ momentum. The $D_s$ vector to vector plus pseudoscalar production ratio
is measured to be $P_V(x(D_s^+)>0.44)=0.44\pm0.04$

</DOC>
<DOC>
<DOCNO> 8732 </DOCNO>
Field and intensity correlations in random media


  Measurements of the microwave field transmitted through a random medium
allows direct access to the field correlation function, whose complex square is
the short range or C1 contribution to the intensity correlation function C. The
frequency and spatial correlation function are compared to their Fourier pairs,
the time of flight distribution and the specific intensity, respectively. The
longer range contribution to intensity correlation is obtained directly by
subtracting C1 from C and is in good agreement with theory.

</DOC>
<DOC>
<DOCNO> 8101 </DOCNO>
Linear and nonlinear rheology of wormlike micelles


  Several surfactant molecules self-assemble in solution to form long,
cylindrical, flexible wormlike micelles. These micelles can be entangled with
each other leading to viscoelastic phases. The rheological properties of such
phases are very interesting and have been the subject of a large number of
experimental and theoretical studies in recent years. We shall report on our
recent work on the macrorheology, microrheology and nonlinear flow behaviour of
dilute aqueous solutions of a surfactant CTAT (Cetyltrimethylammonium
Tosilate). This system forms elongated micelles and exhibits strong
viscoelasticity at low concentrations ($\sim$ 0.9 wt%) without the addition of
electrolytes. Microrheology measurements of $G(\omega)$ have been done using
diffusing wave spectroscopy which will be compared with the conventional
frequency sweep measurements done using a cone and plate rheometer. The second
part of the paper deals with the nonlinear rheology where the measured shear
stress $\sigma$ is a nonmonotonic function of the shear rate $\dot{\gamma}$. In
stress-controlled experiments, the shear stress shows a plateau for
$\dot{\gamma}$ larger than some critical strain rate, similar to the earlier
reports on CPyCl/NaSal system. Cates et al have proposed that the plateau is a
signature of mechanical instability in the form of shear bands. We have carried
out extensive experiments under controlled strain rate conditions, to study the
time-dependence of shear stress. The measured time series of shear stress has
been analysed in terms of correlation integrals and Lyapunov exponents to show
unambiguously that the behaviour is typical of low dimensional dynamical
systems.

</DOC>
<DOC>
<DOCNO> 12071 </DOCNO>
Two-Fluid Hydrodynamics in Trapped Bose Gases and in Superfluid Helium


  A review is given of recent theoretical work on the superfluid dynamics of
trapped Bose gases at finite temperatures, where there is a significant
fraction of non-condensate atoms. One can now reach large enough densities and
collision cross-sections needed to probe the collective modes in the
collision-dominated hydrodynamic region where the gas exhibits characteristic
superfluid behavior involving the relative motions of the condensate and
non-condensate components. The precise analogue of the Landau-Khalatnikov
two-fluid hydrodynamic equations was recently derived from trapped Bose gases,
starting from a generalized Gross-Pitaevskii equation for the condensate
macroscopic wavefunction and a kinetic equation for the non-condensate atoms.

</DOC>
<DOC>
<DOCNO> 118402 </DOCNO>
ISO Spectroscopy of the HH 7-11 Flow and its red-shifted Counterpart


  We have used the two spectrometers on the Infrared Space Observatory to
observe the HH 7-11 flow, its red-shifted counterpart, and the candidate
exciting source SVS 13, in the star formation region NGC 1333. We detect atomic
([OI]63um and 145um, [SiII]34.8um, [CII]158um) and molecular (H_2, CO, H_2O)
lines at various positions along the bipolar flow.
  Most of the observed lines can be explained in terms of shock-excited
emission. In particular, our analysis shows that dissociative (J-type) and
non-dissociative (C-type) shocks are simultaneously present everywhere along
both lobes of the flow. We confirm the low-excitation nature of the Herbig-Haro
nebulosities, with shock velocities <40-50 km/s. Toward both lobes of the
outflow we find pre-shock densities of n_0~10^4 cm-3 for both the J and C
components, implying B_0~100uG. In the central region of the flow, close to the
exciting source, the pre-shock density deduced for the C-shock component is
n_0~10^5 cm-3, suggesting a magnetic field ~3 times stronger. We propose that
the deficiency of gas-phase water in the post C-shock regions is due to
freezing onto warm grains processed through the J-shock front and traveling
along the magnetic field lines. The total observed cooling from the
dissociative shock components is consistent with the power lost by a slow
molecular outflow accelerated by a fast neutral HI wind.
  Finally, the skin of the cloud seen in projection toward the flow appears to
be weakly photo-ionised by BD +30 549, the dominant illuminating source of the
NGC 1333 reflection nebula.

</DOC>
<DOC>
<DOCNO> 100207 </DOCNO>
An Eulerian-Lagrangian Approach for Incompressible Fluids: Local Theory


  We present a local existence result for the three dimensional incompressible
Euler equations. The solution is constructed using a formulation of the
equations as an active vector system in Eulerian coordinates. The formulation
employs the inverse of the Lagrangian path map (the "back-to-labels" map) and
its Eulerian gradient. We express sufficient conditions for regularity in terms
of this gradient.

</DOC>
<DOC>
<DOCNO> 122517 </DOCNO>
VLA HI Zeeman Observations Toward the W49 Complex


  We report VLA HI Zeeman observations toward the W49A star-forming region and
the SNR W49B. Line of sight magnetic fields (Blos) of 60 to 300 muG at 25"
resolution were detected toward W49A at velocities of ~4 and ~7 km/s. The Blos
values measured toward W49A show a significant increase in field strength with
higher resolution especially for the ~4 km/s HI gas. The HI gas in the velocity
range -5 to 25 km/s toward W49A shows good agreement both kinematically and
spatially with molecular emission intrinsically associated with W49A. Based on
comparisons with molecular data toward W49A, we suggest that the 4 km/s HI gas
is directly associated with the northern part of the HII region ring, while the
7 km/s HI gas seems to originate in a lower density halo surrounding W49A. We
estimate that the W49A North core is significantly subvirial, and that the
total kinetic +magnetic energies amount to less than 1/3 of the total W49A
North gravitational energy. These magnetic field results suggest that W49A
North is unstable to overall gravitational collapse in agreement with evidence
that the halo is collapsing onto the W49A North ring of HII regions.
  The majority of the HI column density toward W49B comes from Sagittarius Arm
clouds along the line of sight at ~40 km/s and ~60 km/s. No significant
magnetic fields were detected toward W49B. Comparison of the spectral
distribution of HI gas toward W49A and W49B suggests that evidence placing W49B
3 kpc closer to the sun (i.e. at 8 kpc) than W49A is quite weak.

</DOC>
<DOC>
<DOCNO> 70897 </DOCNO>
Contribution of Inelastic Rescatterring to $B \to \pi \pi, K \bar{K}$


  We discuss multichannel inelastic rescatterring effects in B decays into a
pair $PP$ of pseudoscalar mesons ($PP = \pi \pi$ or $K\bar{K}$). In agreement
with short-distance models it is assumed that initially $B$ meson decays
dominantly into jet-like states composed of two flying-apart low-mass
resonances $M_1 M_2$ which rescatter into $PP$. Since from all S-matrix
elements $<i|S|PP>$ involving $PP$ only some ($i = M_1 M_2$) contribute to the
final state rescatterring, the latter is treated as a correction only. The
rescatterring of resonance pair $M_1 M_2$ into the final $PP$ state is assumed
to proceed through Regge exchange. Although effects due to a single
intermediate state $M_1 M_2$ are small, it is shown that the combined effect of
all such states should be large. In particular, amplitudes of B decays into
$K\bar{K}$ become significantly larger than those estimated through
short-distance penguin diagrams, to the point of being comparable to the $B\to
\pi \pi$ amplitudes.

</DOC>
<DOC>
<DOCNO> 118967 </DOCNO>
Cluster Detection in Astronomical Databases: the Adaptive Matched Filter


  Clusters of galaxies are the most massive objects in the Universe and mapping
their location is an important astronomical problem. This paper describes an
algorithm (based on statistical signal processing methods), a software
architecture (based on a hybrid layered approach) and a parallelization scheme
(based on a client/server model) for finding clusters of galaxies in large
astronomical databases. The Adaptive Matched Filter (AMF) algorithm presented
here identifies clusters by finding the peaks in a cluster likelihood map
generated by convolving a galaxy survey with a filter based on a cluster model
and a background model. The method has proved successful in identifying
clusters in real and simulated data. The implementation is flexible and readily
executed in parallel on a network of workstations.

</DOC>
<DOC>
<DOCNO> 122875 </DOCNO>
Near-infrared spectroscopy of the circumnuclear star formation regions


  We present low resolution (R~450) K-band spectroscopy for 16 of the 43
circumnuclear star-forming knots in M100 identified by Ryder & Knapen (1999).
We compare our measurements of equivalent widths for the Br-gamma emission line
and CO 2.29 micron absorption band in each knot with the predictions of
starburst models from the literature, and derive ages and burst parameters for
the knots. The majority of these knots are best explained by the result of
short, localised bursts of star formation between 8 and 10 Myr ago. By
examining both radial and azimuthal trends in the age distribution, we present
a case for sequential triggering of star formation, most likely due to the
action of a large-scale shock. In an appendix, we draw attention to the fact
that the growth in the CO spectroscopic index with decreasing temperature in
supergiant stars is not as regular as is commonly assumed.

</DOC>
<DOC>
<DOCNO> 8795 </DOCNO>
What angle-resolved photemission experiments tell about the microscopic


  Recent angular-resolved photoemission experiments on high-temperature
superconductors are consistent with a phenomenological description of the
normal state of these materials as Marginal Fermi Liquids. The experiments also
provide constraints on microscopic theories

</DOC>
<DOC>
<DOCNO> 70651 </DOCNO>
A solution to the mu problem in the presence of a heavy gluino LSP


  In this paper we present a solution to the $\mu$ problem in an SO(10)
supersymmetric grand unified model with gauge mediated and D-term supersymmetry
breaking. A Peccei-Quinn symmetry is broken at the messenger scale $M\sim
10^{12}$ GeV and enables the generation of the $\mu$ term. The boundary
conditions defined at $M$ lead to a phenomenologically acceptable version of
the minimal supersymmetric standard model with novel particle phenomenology.
Either the gluino or the gravitino is the lightest supersymmetric particle
(LSP). If the gravitino is the LSP, then the gluino is the next-to-LSP (NLSP)
with a lifetime on the order of one month or longer. In either case this heavy
gluino, with mass in the range 25 - 35 GeV, can be treated as a stable particle
with respect to experiments at high energy accelerators. Given the extensive
phenomenological constraints we show that the model can only survive in a
narrow region of parameter space resulting in a light neutral Higgs with mass
$\sim 86 - 91$ GeV and $\tan\beta \sim 9 - 14$. In addition the lightest stop
and neutralino have mass $\sim 100 - 122$ GeV and $\sim 50 - 72$ GeV,
respectively. Thus the model will soon be tested. Finally, the invisible axion
resulting from PQ symmetry breaking is a cold dark matter candidate.

</DOC>
<DOC>
<DOCNO> 12132 </DOCNO>
Shot noise measurements in NS junctions and the semiclassical theory


  We present a new analysis of shot noise measurements in normal
metal-superconductor (NS) junctions [X. Jehl et al., Nature 405, 50 (2000)],
based on a recent semiclassical theory. The first calculations at zero
temperature assuming quantum coherence predicted shot noise in NS contacts to
be doubled with respect to normal contacts. The semiclassical approach gives
the first opportunity to compare data and theory quantitatively at finite
voltage and temperature. The doubling of shot noise is predicted up to the
superconducting gap, as already observed, confirming that phase coherence is
not necessary. An excellent agreement is also found above the gap where the
noise follows the normal case.

</DOC>
<DOC>
<DOCNO> 120623 </DOCNO>
Advective Accretion Flows: Ten Years Later


  Ten years have passed since the global solutions of advective accretion disks
around black holes and neutron stars were first discovered. Since then they are
enjoying support from observers almost on a daily basis, more so in recent days
with the launching of very high resolution satellites. This review presents the
development of the subject of advective accretion in last twenty five years
leading to the global solutions and their applications. It also shows that
apart from the standard Keplerian disk features in most part of the accretion
flow, future models must incorporate the essential features of the advective
disks, such as the advection of energy and entropy by the flow, centrifugal
barrier supported boundary layer of a black hole, steady and non-steady shocks,
the bulk motion Comptonization of matter close to the black hole, outflows from
the centrifugal barrier etc. Since black holes are `black', methods of their
identification must be indirect, and therefore, the solutions must be known
very accurately. On the horizon, matter moves supersonically, but just before
that it is subsonic due to centrifugal pressure dominated boundary layer or
CENBOL where much of the infall energy is released and outflows are generated.
In this review, we show that advective flow models treat accretion and winds
onto black holes and neutron stars in the same footing. Similarly treated are
the steady and time-dependent behaviour of the boundary layers of neutron stars
and the black holes!

</DOC>
<DOC>
<DOCNO> 101561 </DOCNO>
On the Family of Pentagonal curves of genus 6 and associated modular


  In this article we study the inverse of the period map for the family
$\mathcal{F}$ of complex algebraic curves of genus 6 equipped with an
automorphism of order 5. This is a family with 2 parameters, and is fibred over
a certain type of Del Pezzo surace. The period satisfies the hypergeometric
differential equation for Appell's $F_1({3/5},{3/5},{2/5},{6/5})$ of two
variables after a certain normalization of the variable parameter. This
differential equation and the family $\mathcal{F}$ are studied by G. Shimura
(1964), T. Terada (1983, 1985), P. Deligne - G.D. Mostow (1986) and T.
Yamazaki- M. Yoshida(1984). Recently M. Yoshida presented a new approch using
the concept of configration space. Based on their results we show the
representation of the inverse of the period map in terms of Riemann theta
constants. This is the first variant of the work of H. Shiga (1981) and K.
Matsumoto (1989, 2000) to the co-compact case.

</DOC>
<DOC>
<DOCNO> 12420 </DOCNO>
Kondo effect in Normal-Superconductor Quantum Dots


  We study the transport properties of a quantum dot coupled to a normal and a
superconducting lead. The dot is represented by a generalized Anderson model.
Correlation effects are taken into account by an appropriate self-energy which
interpolates between the limits of weak and strong coupling to the leads. The
transport properties of the system are controlled by the interplay between the
Kondo effect and Andreev reflection processes. We show that, depending on the
parameters range the conductance can either be enhanced or suppressed as
compared to the normal case. In particular, by adequately tunning the coupling
to the leads one can reach the maximum value $4e^2/h$ for the conductance.

</DOC>
<DOC>
<DOCNO> 67755 </DOCNO>
The State of the Standard Model


  I quickly review the successes of quantum chromodynamics. Then I assess the
current state of the electroweak theory, making brief comments about the search
for the Higgs boson and some of the open issues for the theory. I sketch the
problems of mass and mass scales, and point to a speculative link between the
question of identity and large extra dimensions. To conclude, I return to QCD
and the possibility that its phase structure might inform our understanding of
electroweak symmetry breaking.

</DOC>
<DOC>
<DOCNO> 152528 </DOCNO>
Nonlinear Realization of Partially Broken N=2 AdS Supersymmetry in Two


  We investigate the nonlinear realization of partially broken $N$=2 global
supersymmetry in the D=2 and 3 anti de-Sitter (AdS) space. We particularly
study Nambu-Goldstone degrees of freedom for the $N$=2 AdS supersymmetry
partially broken down to $N$=1 AdS supersymmetry, where we observe a NG fermion
of the broken supersymmetry and a NG boson of the internal symmetry which form
a NG multiplet. Based on the nonlinear realization method, we construct a
superspace formalism for 2 and 3 dimensional AdS space and evaluate the
covariant derivatives and supervielbeins for the AdS superspace. Finally we
obtain the nonlinear transformation laws and the lowest order of effective
Lagrangians.

</DOC>
<DOC>
<DOCNO> 151486 </DOCNO>
Quantum Stabilization of Compactified AdS_5


  We investigate the role of quantum fluctuations in the system composed of two
branes bounding a region of AdS. It is shown that the modulus effective
potential generated by quantum fluctuations of both brane and bulk fields is
incapable of stabilizing the space naturally at the separation needed to
generate the hierarchy. Consequently, a classical stabilization mechanism is
required. We describe the proper method of regulating the loop integrals and
show that, for large brane separation, the quantum effects are power suppressed
and therefore have negligible affects on the bulk dynamics once a classical
stabilization mechanism is in place.

</DOC>
<DOC>
<DOCNO> 121252 </DOCNO>
Cosmological Perturbations with Multiple Scalar Fields


  We consider the evolution of perturbed cosmological spacetime with multiple
scalar fields in Einstein gravity. A complete set of scalar-type perturbation
equations is presented in a gauge-ready form, and we derived the closed set of
second-order differential equations in several useful forms. Conserved
behaviors of the perturbed three-space curvature in the comoving gauge,
$\phi_v$, under several conditions are clarified. Under the slow-roll
conditions, the adiabatic and isocurvature modes decouple from each other, and
in the large-scale limit we have (i) the adiabatic mode is generally conserved,
(ii) for a couple of special potential the isocurvature modes decouple from
each other and are described by conserved quantities, (iii) in the two field
system, the isocurvature mode is described by a conserved quantity for the
general potential.

</DOC>
<DOC>
<DOCNO> 119430 </DOCNO>
EUV Flare Activity in Late-Type Stars


  \textit{Extreme Ultraviolet Explorer} Deep Survey observations of cool stars
(spectral type F to M) have been used to investigate the distribution of
coronal flare rates in energy and its relation to activity indicators and
rotation parameters. Cumulative and differential flare rate distributions were
constructed and fitted with different methods. Power laws are found to
approximately describe the distributions. A trend toward flatter distributions
for later-type stars is suggested in our sample. Assuming that the power laws
continue below the detection limit, we have estimated that the superposition of
flares with radiated energies of about $10^{29}-10^{31}$ergs could explain the
observed radiative power loss of these coronae, while the detected flares are
contributing only $\approx 10$%. While the power-law index is not correlated
with rotation parameters (rotation period, projected rotational velocity,
Rossby number) and only marginally with the X-ray luminosity, the flare
occurrence rate is correlated with all of them. The occurrence rate of flares
with energies larger than $10^{32}$ergs is found to be proportional to the
average total stellar X-ray luminosity. Thus, energetic flares occur more often
in X-ray bright stars than in X-ray faint stars. The normalized occurrence rate
of flares with energies larger than $10^{32}$ergs increases with increasing
\lxlbol and stays constant for saturated stars. A similar saturation is found
below a critical Rossby number. The findings are discussed in terms of simple
statistical flare models in an attempt to explain the previously observed trend
for higher average coronal temperatures in more active stars. It is concluded
that flares can contribute a significant amount of energy to coronal heating in
active stars.

</DOC>
<DOC>
<DOCNO> 71167 </DOCNO>
The Directional Rate and the Modulation Effect for Direct Supersymmetric


  The detection of the theoretically expected dark matter is central to
particle physics and cosmology. Current fashionable supersymmetric models
provide a natural dark matter candidate which is the lightest supersymmetric
particle (LSP). Such models combined with fairly well understood physics like
the quark substructure of the nucleon and the nuclear structure (form factor
and/or spin response function), permit the evaluation of the event rate for
LSP-nucleus elastic scattering. The thus obtained event rates are, however,
very low. So it is imperative to exploit the modulation effect, i.e. the
dependence of the event rate on the earth's annual motion. Also it is useful to
consider the directional rate, i.e its dependence on the direction of the
recoiling nucleus. In this paper we study the modulation effect both in non
directional and directional experiments. We calculate both the differential and
the total rates usingi both isothermal, symmetric as well as only axially
asymmetric, and non isothermal, due to caustic rings, velocity distributions.
We consider We find that in the symmetric case the modulation amplitude is
small. The same is true for the case of caustic rings. The inclusion of
asymmetry, with a enhanced velocity dispersion in the galactocentric direction,
yields an enhanced modulation effect, especially in directional experiments.

</DOC>
<DOC>
<DOCNO> 117968 </DOCNO>
The Nature of Composite LINER/HII Galaxies, As Revealed from


  A sample of 37 nearby galaxies displaying composite LINER/HII and pure HII
spectra was observed with the VLA in an investigation of the nature of their
weak radio emission. The resulting radio contour maps overlaid on optical
galaxy images are presented here, together with an extensive literature list
and discussion of the individual galaxies. Radio morphological data permit
assessment of the ``classical AGN'' contribution to the global activity
observed in these ``transition'' LINER galaxies. One in five of the latter
objects display clear AGN characteristics: these occur exclusively in
bulge-dominated hosts.

</DOC>
<DOC>
<DOCNO> 80647 </DOCNO>
Low-lying Eigenvalues of the QCD Dirac Operator at Finite Temperature


  We compute the low-lying spectrum of the staggered Dirac operator above and
below the finite temperature phase transition in both quenched QCD and in
dynamical four flavor QCD. In both cases we find, in the high temperature
phase, a density with close to square root behavior, $\rho(\lambda) \sim
(\lambda-\lambda_0)^{1/2}$. In the quenched simulations we find, in addition, a
volume independent tail of small eigenvalues extending down to zero. In the
dynamical simulations we also find a tail, decreasing with decreasing mass, at
the small end of the spectrum. However, the tail falls off quite quickly and
does not seem to extend to zero at these couplings. We find that the
distribution of the smallest Dirac operator eigenvalues provides an efficient
observable for an accurate determination of the location of the chiral phase
transition, as first suggested by Jackson and Verbaarschot.

</DOC>
<DOC>
<DOCNO> 152122 </DOCNO>
Space-Time Uncertainty and Noncommutativity in String Theory


  We analyze the nature of space-time nonlocality in string theory. After
giving a brief overview on the conjecture of the space-time uncertainty
principle, a (semi-classical) reformulation of string quantum mechanics, in
which the dynamics is represented by the noncommutativity between temporal and
spatial coordinates, is outlined. The formalism is then compared to the
space-time noncommutative field theories associated with nonzero electric
B-fields.

</DOC>
<DOC>
<DOCNO> 121393 </DOCNO>
An Empirical Procedure to Estimate Distances to Stellar Clusters


  A most desirable feature of a standard candle to estimate astronomical
distances is robustness against changes in metallicity and age. It is argued
that the radii of main sequence stars with spectral types from solar to A0 show
predictable changes with metallicity, and detectable changes with evolution.
Such stars populate the solar neighborhood, and therefore benefit from
measurements of angular diameters. Also, reliable determinations of their
masses and radii are available from observations of eclipsing binaries. Three
empirical relationships are defined and suggested for estimating distances to
dwarfs from only BVK photometry. Comparison with HIPPARCOS trigonometric
parallaxes shows that the method provides errors of about 15% for a particular
star, which can be reduced to roughly 1.5% when applied to young clusters (age
<~ 1-2 Gyr) with ~ 100 stars of the appropriate spectral types. If reddening is
unknown, main sequence stars with effective temperatures close to 8000 K can
constrain it, although an estimate of R=A(V)/E(B-V) is required.

</DOC>
<DOC>
<DOCNO> 123081 </DOCNO>
An Upgraded Data Acquisition System for the Balloon-Borne Liquid Xenon


  LXeGRIT is a balloon-borne Compton telescope for MeV gamma-ray astrophysics,
based on a liquid xenon time projection chamber (LXe-TPC) with charge and light
readout. The first balloon flights in 1997 revealed limitations of the trigger
electronics and the data acquisition (DAQ) system, leading to their upgrade.
New electronics was developed to handle the xenon scintillation light trigger.
The original processor module was replaced by a commercial VME processor. The
telemetry rate was doubled to 2 x 500 kbps and onboard data storage on hard
disks was implemented. Relying on a robust real-time operating system, the new
DAQ software adopts an object oriented design to implement the diverse tasks of
trigger handling, data selection, transmission, and storage, as well as DAQ
control and monitor functions. The new systems performed well during two
flights in Spring 1999 and Fall 2000. In the 2000 flight, the DAQ system was
able to handle 300-350 triggers/s out of a total of about 650 Hz, including
charged particles.

</DOC>
<DOC>
<DOCNO> 40366 </DOCNO>
TAC Proposal for Fundamental and Applied Research


  Main parameters of linac-ring type $phi$ factory and 1-5 GeV energy proton
synchrotron proposed in the framework of the Turkic Accelerator Complex (TAC)
Project are discussed

</DOC>
<DOC>
<DOCNO> 84859 </DOCNO>
Riemannian geometry of quantum groups and finite groups with


  We construct noncommutative `Riemannian manifold' structures on dual
quasitriangular Hopf algebras such as $C_q[SU_2]$ with its standard bicovariant
differential calculus, using the quantum frame bundle formalism introduced
previously. The metric is provided by the braided-Killing form on the
braided-Lie algebra on the tangent space and the $n$-bein by the Maurer-Cartan
form. We also apply the theory to finite sets and in particular to finite group
function algebras $C[G]$ with differential calculi and Killing forms determined
by a conjugacy class. The case of the permutation group $C[S_3]$ is worked out
in full detail and a unique torsion free and cotorsion free or `Levi-Civita'
connection is obtained with noncommutative Ricci curvature essentially
proportional to the metric (an Einstein space). We also construct Dirac
operators in the metric background, including on finite groups such as $S_3$.
In the process we clarify the construction of connections from gauge fields
with nonuniversal calculi on quantum principal bundles of tensor product form.

</DOC>
<DOC>
<DOCNO> 70490 </DOCNO>
Single neutral heavy lepton production at electron-muon colliders


  New heavy Majorana and Dirac neutrinos production at future electron-muon
colliders are investigated. The production of a single heavy neutrino is shown
to be more relevant than pair production when comparing cross sections and
neutrino mass ranges. The process $e^\pm \mu^\mp \longrightarrow {\nu}
\ell^{\pm} W^{\mp}$ is studied including on-shell and off-shell heavy neutrino
effects. Distributions are calculated including hadronization effects and
experimental cuts that suppress background, in order to have a clear signal for
heavy neutral leptons.

</DOC>
<DOC>
<DOCNO> 102000 </DOCNO>
Generating Functions, Weighted and Non-Weighted Sums for Powers of


  In this paper we find closed form for the generating function of powers of
any non-degenerate second-order recurrence sequence, completing a study begun
by Carlitz and Riordan in 1962. Moreover, we generalize a theorem of Horadam on
partial sums involving such sequences. Also, we find closed forms for weighted
(by binomial coefficients) partial sums of powers of any non-degenerate
second-order recurrence sequences. As corollaries we give some known and
seemingly unknown identities and derive some very interesting congruence
relations involving Fibonacci and Lucas sequences.

</DOC>
<DOC>
<DOCNO> 152395 </DOCNO>
Superparticle and superstring in AdS_3 x S^3 Ramond-Ramond background in


  We discuss superparticle and superstring dynamics in AdS_3 x S^3 supported by
R-R 3-form background using light-cone gauge approach. Starting with the
superalgebra psu(1,1|2) + psu(1,1|2) representing the basic symmetry of this
background we find the light-cone superparticle Hamiltonian. We determine the
harmonic decomposition of light-cone superfield describing fluctuations of type
IIB supergravity fields expanded near AdS_3 x S^3 background and compute the
corresponding Kaluza-Klein spectrum. We fix the fermionic and bosonic
light-cone gauges in the covariant Green-Schwarz AdS_3 x S^3 superstring action
and find the light-cone string Hamiltonian. We also obtain a realization of the
generators of psu(1,1|2) + psu(1,1|2) in terms of the superstring 2-d fields in
the light-cone gauge.

</DOC>
<DOC>
<DOCNO> 13110 </DOCNO>
Universal Structure of the Personal Income Distribution


  We investigate the Japanese personal income distribution in the high income
range over the 112 years 1887-1998, and that in the middle income range over
the 44 years 1955-98. It is observed that the distribution pattern of the
lognormal with power law tail is the universal structure. However the indexes
specifying the distribution differ from year to year. One of the index
characterizing the distribution is the mean value of the lognormal
distribution; the mean income in the middle income range. It is found that this
value correlates linearly with the Gross Domestic Product (GDP). To clarify the
temporal change of the equality or inequality of the distribution, we analyze
Pareto and Gibrat indexes, which characterize the distribution in the high
income range and that in the middle income range respectively. It is found for
some years that there is no correlation between the high income and the middle
income. It is also shown that the mean value of Pareto index equals to 2, and
the change of this index is effected by the change of the asset price. From
these analysis we derive four constraints that must be satisfied by
mathematical models.

</DOC>
<DOC>
<DOCNO> 70845 </DOCNO>
Clustering in Highest Energy Cosmic Rays: Physics or Statistics?


  Directional clustering can be expected in cosmic ray observations due to
purely statistical fluctuations for sources distributed randomly in the sky. We
develop an analytic approach to estimate the probability of random cluster
configurations, and use these results to study the strong potential of the
HiRes, Auger, Telescope Array and EUSO/OWL/AirWatch facilities for deciding
whether any observed clustering is most likely due to non-random sources.

</DOC>
<DOC>
<DOCNO> 9620 </DOCNO>
Spin 1/2 Magnetic Impurity in a 2D Magnetic System Close to Quantum


  We consider a magnetic impurity in a spin liquid state of a magnetic system
which is close to the quantum phase transition to the magnetically ordered
state. There is similarity between this problem and the Kondo problem. We
derive the impurity Green's function, consider renormalizations of the magnetic
moments of the impurity, calculate critical indexes for the magnetic
susceptibilities and finally consider specific heat and magnetic interaction of
two impurities.

</DOC>
<DOC>
<DOCNO> 83271 </DOCNO>
Turning Speech Into Scripts


  We describe an architecture for implementing spoken natural language dialogue
interfaces to semi-autonomous systems, in which the central idea is to
transform the input speech signal through successive levels of representation
corresponding roughly to linguistic knowledge, dialogue knowledge, and domain
knowledge. The final representation is an executable program in a simple
scripting language equivalent to a subset of Cshell. At each stage of the
translation process, an input is transformed into an output, producing as a
byproduct a "meta-output" which describes the nature of the transformation
performed. We show how consistent use of the output/meta-output distinction
permits a simple and perspicuous treatment of apparently diverse topics
including resolution of pronouns, correction of user misconceptions, and
optimization of scripts. The methods described have been concretely realized in
a prototype speech interface to a simulation of the Personal Satellite
Assistant.

</DOC>
<DOC>
<DOCNO> 150431 </DOCNO>
Renormalization of noncommutative Yang-Mills theories: A simple example


  We prove by explicit calculation that Feynman graphs in noncommutative
Yang-Mills theory made of repeated insertions into itself of arbitrarily many
one-loop ghost propagator corrections are renormalizable by local counterterms.
This provides a strong support for the renormalizability conjecture of that
model.

</DOC>
<DOC>
<DOCNO> 70043 </DOCNO>
(Non)Thermal Aspects of Charmonium Production and a New Look at J/$\psi$


  To investigate a recent proposal that J/$\psi$ production in
ultra-relativistic nuclear collisions is of thermal origin we have reanalyzed
the data from the NA38/50 collaboration within a thermal model including charm.
Comparison of the calculated with measured yields demonstrates the non-thermal
origin of hidden charm production at SPS energy. However, the ratio
$\psi^{'}$/(J/$\psi)$ exhibits, in central nucleus-nucleus collisions, thermal
features which lead us to a new interpretation of open charm and charmonium
production at SPS energy. Implications for RHIC and LHC energy measurements
will be discussed.

</DOC>
<DOC>
<DOCNO> 13515 </DOCNO>
Force chain splitting in granular materials: a mechanism for large scale


  We investigate both numerically and analytically the effect of strong
disorder on the large scale properties of the hyperbolic equations for stresses
proposed in \protect\cite{bcc,wcc}. The physical mechanism that we model is the
local splitting of the force chains (the characteristics of the hyperbolic
equation) by packing defects. In analogy with the theory of light diffusion in
a turbid medium, we propose a Boltzmann-like equation to describe these
processes. We show that, for isotropic packings, the resulting large scale
effective equations for the stresses have exactly the same structure as those
of an elastic body, despite the fact that no displacement field needs to be
introduced at all. Correspondingly, the response function evolves from a two
peak structure at short scales to a broad hump at large scales. We find,
however, that the Poisson ratio is anomalously large and incompatible with
classical elasticity theory that requires the reference state to be
thermodynamically stable.

</DOC>
<DOC>
<DOCNO> 116650 </DOCNO>
On Standard Model Higgs and Superstring Theories


  It is shown that in the Standard Model, the property of charge quantization
holds for a Higgs with arbitrary isospin and hypercharge. These defining
quantum numbers of the Higgs remain unconstrained while the whole basic and
fundamental structure of the Standard Model remains intact. Hence it is shown
that the Higgs cannot be a physical particle. Higgs is the underlying `vacuum'
over which the whole edifice of the Standard Model stands. Also on most general
grounds it is established here that as per the Standard Model there is no
electric charge above the electro-weak phase transition temperature. Hence
there was no electric charge present in the Early Universe. The Superstring
Theories are flawed in as much as they are incompatible with this requirement.

</DOC>
<DOC>
<DOCNO> 40181 </DOCNO>
Meeting Tight Frequency Requirement of Rounded Damped Detuned Structure


  Following successful design and fabrication of damped detuned structures, the
R&D for the accelerating structures of the NLC/JLC linear collider project
proceeded to studies of Rounded Damped Detuned Structure with curved cross
section of the cavity shape for increased shunt impedance. The important
features of the structure are the accurately tuned accelerating mode frequency
and the distribution of the first dipole modes smooth and close to the design
distribution. These requirements were met based on the high-accuracy diamond
turning with its capability to realize the periphery tolerance of two microns.
The lowest dipole mode frequencies scattered by 0.6 MHz RMS. The error in the
accelerating mode frequency averaged over a structure was 0.1 MHz by applying a
feed-forward method.

</DOC>
<DOC>
<DOCNO> 71163 </DOCNO>
Next-to-next-to-leading logarithmic threshold resummation for


  The soft-gluon resummation exponents G^N in moment space are investigated for
the quark coefficient functions in deep-inelastic structure functions and the
quark-antiquark contribution to the Drell-Yan cross section dsigma/dM.
Employing results from two- and three-loop calculations we obtain the
next-to-next-to-leading logarithmic terms alpha_s (alpha_s ln N)^n of G^N to
all orders in the strong coupling constant alpha_s. These new contributions
facilitate a reliable assessment of the numerical effect and the stability of
the large-N expansion.

</DOC>
<DOC>
<DOCNO> 68804 </DOCNO>
A new global analysis of DIS data and the strange sea distribution


  We present the results of a new global analysis of DIS data characterized by
an enlarged neutrino and antineutrino data set. Special emphasis is given to
the strange sector. The strange sea distribution is determined independently of
the non strange sea. The possibility of a charge asymmetry, s(x) different from
sbar(x), is tested.

</DOC>
<DOC>
<DOCNO> 69838 </DOCNO>
Minimal extended flavor groups, matter fields chiral representations,


  We show the specific unusual features on chiral gauge anomalies cancellation
in the minimal, necessarily 3-3-1, and the largest
 3-4-1 weak isospin chiral gauge semisimple group leptoquark-bilepton
extensions of the 3-2-1 conventional standard model of nuclear and
electromagnetic interactions. In such models a natural explanation for the
fundamental question of fermion generation replication arises from the
self-consistency of a local gauge quantum field theory, which constrains the
number of the
 QFD fermion families to the QCD color charges.

</DOC>
<DOC>
<DOCNO> 70213 </DOCNO>
Skewed parton distributions and the scale dependence of the transverse


  We discuss the scale dependence of a skewed parton distribution of the pion
obtained from a generalized light-cone wave function overlap formula. Using a
simple ansatz for the transverse momentum dependence of the light-cone wave
function and restricting ourselves to the case of a zero skewedness parameter,
the skewed parton distribution can be expressed through an ordinary parton
distribution multiplied by an exponential function. Matching the generalized
and ordinary DGLAP evolution equations of the skewed and ordinary parton
distributions, respectively, we derive a constraint for the scale dependence of
the transverse size parameter, which describes the width of the pion wave
function in transverse momentum space. This constraint has implications for the
Fock state probability and valence distribution. We apply our results to the
pion form factor.

</DOC>
<DOC>
<DOCNO> 9791 </DOCNO>
Adsorbed states of a long - flexible polymer chain


  A phase diagram for a surface-interacting long flexible polymer chain in a
two-dimensional poor solvent where the possibility of collapse exists is
determined using exact enumeration method. A model of a self-attracting self
avoiding walk (SASAW) on a square lattice was considered and up to 28 steps in
series were evaluated. A new adsorbed state having the conformation of a
surface attached globule is found. Four phases (i) desorbed expanded, (ii)
desorbed collapsed, (iii) adsorbed expanded and (iv) surface attached globule
are found to meet at a point on the adsorption line.

</DOC>
<DOC>
<DOCNO> 122017 </DOCNO>
Limits on Collisional Dark Matter from Elliptical Galaxies in Clusters


  The dynamical evolution of galaxies in clusters is modified if dark matter is
self-interacting. Heat conduction from the hot cluster halo leads to
evaporation of the relatively cooler galactic halos. The stellar distribution
would adiabatically expand as it readjusts to the loss of dark matter, reducing
the velocity dispersion and increasing the half-light radius. If the dark
matter content within that radius was f_dm = 25-50% of the total, as indicated
by current observations, the ellipticals in clusters would be offset from the
fundamental plane relation beyond the observational scatter. The requirement
that their halos survive for a Hubble time appears to exclude just that range
of the dark matter cross-section, 0.3 < sigma/m < 10^4 cm^2/g, thought to be
optimal for reducing central halo cusps, unless f_dm < 15%. If the
cross-section is allowed to vary with the relative velocity of dark matter
particles, sigma \propto v^{-2 delta}, a new problem of evaporation of dark
matter arises in the dwarf galaxies with low velocity dispersion. The halos of
large galaxies in clusters and dwarf galaxies in the Local Group can both
survive only if delta < 1.1 or delta > 1.8. In either case the problem of
central density cusps remains.

</DOC>
<DOC>
<DOCNO> 68146 </DOCNO>
Neutrinoless double beta decay and new physics in the neutrino sector


  Neutrinoless double beta decay belongs to the most sensitive tools for the
search of new physics beyond the standard model. The recent half life limit of
the Heidelberg-Moscow experiment implies restrictive bounds on the absolute
mass scale in the neutrino sector. Possible improvements by the GENIUS project
provide a unique possibility to reconstruct the neutrino mass spectrum. Further
constraints on new interactions in the neutrino sector are given in a
model-independent way. Consequences for neutrino anomalies and theories beyond
the standard model such as left-right symmetric models, R-parity violating SUSY
and leptoquarks are discussed. The potential of double beta decay experiments
in the search for WIMP dark matter is reviewed.

</DOC>
<DOC>
<DOCNO> 14040 </DOCNO>
Glassy Spin Dynamics in Non-Fermi-Liquid UCu_{5-x}Pd_x, x = 1.0 and 1.5


  Local f-electron spin dynamics in the non-Fermi-liquid heavy-fermion alloys
UCu_{5-x}Pd_x, x = 1.0 and 1.5, have been studied using muon spin-lattice
relaxation. The sample-averaged asymmetry function Gbar(t) indicates strongly
inhomogeneous spin fluctuations, and exhibits the scaling Gbar(t,H) =
Gbar(t/H^\gamma) expected from glassy dynamics. At 0.05 K \gamma(x=1.0) = 0.35
\pm 0.1, but \gamma(x=1.5) = 0.7 \pm 0.1. This is in contrast to inelastic
neutron scattering results, which yield \gamma = 0.33 for both concentrations.
There is no sign of static magnetism \gtrsim 10^{-3} \mu_B/U ion in either
material above 0.05 K. Our results strongy suggest that both alloys are quantum
spin glasses.

</DOC>
<DOC>
<DOCNO> 13666 </DOCNO>
Test Particle in a Quantum Gas


  A master equation with a Lindblad structure is derived, which describes the
interaction of a test particle with a macroscopic system and is expressed in
terms of the operator valued dynamic structure factor of the system. In the
case of a free Fermi or Bose gas the result is evaluated in the Brownian limit,
thus obtaining a single generator master equation for the description of
quantum Brownian motion in which the correction due to quantum statistics is
explicitly calculated. The friction coefficients for Boltzmann and Bose or
Fermi statistics are compared.

</DOC>
<DOC>
<DOCNO> 118002 </DOCNO>
ISO spectroscopy of circumstellar dust in the Herbig Ae systems AB Aur


  Using both the Short- and Long-wavelength Spectrometers on board the Infrared
Space Observatory (ISO), we have obtained infrared spectra of the Herbig Ae
systems AB Aur and HD 163296. In addition, we obtained ground-based N band
images of HD 163296. Our results can be summarized as follows: (1) The main
dust components in AB Aur are amorphous silicates, iron oxide and PAHs; (2) The
circumstellar dust in HD 163296 consists of amorphous silicates, iron oxide,
water ice and a small fraction of crystalline silicates; (3) The infrared
fluxes of HD 163296 are dominated by solid state features; (4) The colour
temperature of the underlying continuum is much cooler in HD 163296 than in AB
Aur, pointing to the existence of a population of very large (mm sized) dust
grains in HD 163296; (5) The composition and degree of crystallization of
circumstellar dust are poorly correlated with the age of the central star. The
processes of crystallization and grain growth are also not necessarily coupled.
This means that either the evolution of circumstellar dust in protoplanetary
disks happens very rapidly (within a few Myr), or that this evolution is
governed by factors other than stellar mass and age.

</DOC>
<DOC>
<DOCNO> 71178 </DOCNO>
New Developments and Applications of Thermal Field Theory


  The lecture provides an introduction to thermal field theory and its
applications to the physics of the quark-gluon plasma, possibly created in
relativistic heavy ion collisions. In particular the Hard Thermal Loop
resummation technique, providing a consistent perturbative description of
relativistic, high-temperature plasmas is introduced. Using this method
interesting quantities of the quark-gluon plasma (damping rates, energy loss,
photon and dilepton production) are discussed. Furthermore recent developments
on non-equilibrium field theory, which are relevant for high-energy heavy ion
physics, are presented.

</DOC>
<DOC>
<DOCNO> 102434 </DOCNO>
Some Remarks on the Fucik Spectrum of the p-Laplacian and Critical


  We compute critical groups of variational functionals arising from
quasilinear elliptic boundary value problems with jumping nonlinearities, when
the asymptotic limits of the equation lie in various regions of the plane that
are separated by certain curves of the Fucik spectrum. As an application some
existence and multiplicity results are established via Morse theoretic and
perturbation arguments.

</DOC>
<DOC>
<DOCNO> 12155 </DOCNO>
Polarizability and Absorption of Small Conducting Particles in a


  We study small conducting particles and thin films in an oscillating
longitudinal electric field. We find the charge, current, and field
distribution in the particle, the polarizability and the electric dipole
absorption. We account for Thomas-Fermi screening by adding a Fick's diffusion
term to Ohm's law. Alternatively, we describe a particle as a dielectric body
with a non-local dielectric constant which is derived in a microscopic
linear-response theory. We show that both approaches are equivalent.

</DOC>
<DOC>
<DOCNO> 8647 </DOCNO>
Meissner - London state in superconductors of rectangular cross-section


  The distribution of magnetic induction in Meissner state with finite London
penetration depth is analyzed for platelet samples of rectangular cross-section
in a perpendicular magnetic field. The exact 2D numerical solution of the
London equation is extended analytically to the realistic 3D case. Data
obtained on Nb cylinders and foils as well as single crystals of YBCO and BSCCO
are in a good agreement with the model. The results are particularly relevant
for magnetic susceptibility, rf and microwave resonator measurements of the
magnetic penetration depth in high-Tc superconductors.

</DOC>
<DOC>
<DOCNO> 72225 </DOCNO>
Results from Bottomonia Production at the Tevatron and Prospects for the


  We extend our previous analysis on inclusive heavy quarkonia hadroproduction
to the whole Upsilon(nS) (n=1,2,3) resonance family. We use a Monte Carlo
framework with the colour-octet mechanism implemented in the PYTHIA event
generator. We include in our study higher order QCD effects such as
initial-state emission of gluons and Altarelli-Parisi evolution of final-state
gluons. We extract some NRQCD colour-octet matrix elements relevant for
Upsilon(nS) (n=1,2,3) hadroproduction from CDF data at the Fermilab Tevatron.
Then we extrapolate to LHC energies to predict prompt bottomonia production
rates. Finally, we examine the prospect to probe the gluon density in protons
from heavy quarkonia inclusive hadroproduction at high transverse momentum and
its feasibility in LHC general-purpose experiments.

</DOC>
<DOC>
<DOCNO> 151918 </DOCNO>
Supergravity M5-branes wrapped on Riemann surfaces and their QFT duals


  We find solutions of 11-dimensional supergravity for M5-branes wrapped on
Riemann surfaces. These solutions preserve ${\cal N} = 2$ four-dimensional
supersymmetry. They are dual to ${\cal N} = 2$ gauge theories, including
non-conformal field theories. We work out the case of ${\cal N} = 2$ Yang-Mills
in detail.

</DOC>
<DOC>
<DOCNO> 84987 </DOCNO>
Energy-momentum and angular momentum densities in gauge theories of


  In the $\bar{\mbox{\rm Poincar\'{e}}}$ gauge theory of gravity, which has
been formulated on the basis of a principal fiber bundle over the space-time
manifold having the covering group of the proper orthochronous Poincar\'{e}
group as the structure group, we examine the tensorial properties of the
dynamical energy-momentum density ${}^{G}{\mathbf T}_{k}{}^{\mu}$ and the ` `
spin" angular momentum density ${}^{G}{\mathbf S}_{kl}{}^{\mu}$ of the
gravitational field. They are both space-time vector densities, and transform
as tensors under {\em global} $SL(2,C)$- transformations. Under {\em local}
internal translation, ${}^{G}{\mathbf T}_{k}{}^{\mu}$ is invariant, while
${}^{G}{\mathbf S}_{kl}{}^{\mu}$ transforms inhomogeneously. The dynamical
energy-momentum density ${}^{M}{\mathbf T}_{k}{}^{\mu}$ and the ` ` spin"
angular momentum density ${}^{M}{\mathbf S}_{kl}{}^{\mu}$ of the matter field
are also examined, and they are known to be space-time vector densities and to
obey tensorial transformation rules under internal $\bar{\mbox{\rm
Poincar\'{e}}}$ gauge transformations. The corresponding discussions in
extended new general relativity which is obtained as a teleparallel limit of
$\bar{\mbox{\rm Poincar\'{e}}}$ gauge theory are also given, and
energy-momentum and ` ` spin" angular momentum densities are known to be well
behaved. Namely, they are all space-time vector densities, etc. In both
theories, integrations of these densities on a space-like surface give the
total energy-momentum and {\em total} (={\em spin}+{\em orbital}) angular
momentum for asymptotically flat space-time. The tensorial properties of
canonical energy-momentum and ` ` extended orbital angular momentum" densities
are also examined.

</DOC>
<DOC>
<DOCNO> 123024 </DOCNO>
On the origin of the Ca-Ti-Cr isotopic anomalies in the inclusion


  In the framework of our investigation to explain the nucleosynthesis origin
of the correlated Ca-Ti-Cr isotopic anomalies in the Ca-Al-rich ''FUN''
inclusion EK-1-4-1 of the Allende meteorite, the nuclear-physics basis in the
neutron-rich N=28 region has been updated by including recent experimental data
on beta-decay properties and microscopic predictions of neutron-capture cross
sections. Charged-particle and subsequent r-process calculations within an
entropy-based approach were performed using a complete reaction network. It is
shown that there exist two astrophysical scenarios within which the observed
isotopic anomalies can be reproduced simultaneously; one at low entropies
(about 10) which confirms the earlier suggestrd Sn Ia mechanism, and another at
high entropies (about 150) which could be compatible with the neutrino-wind
scenario of a SN II.

</DOC>
<DOC>
<DOCNO> 119447 </DOCNO>
Is the diffuse gamma background radiation generated by galactic cosmic


  We explore the possibility that the diffuse gamma-ray background radiation
(GBR) at high galactic latitudes could be dominated by inverse Compton
scattering of cosmic ray (CR) electrons on the cosmic microwave background
radiation and on starlight from our own galaxy. Assuming that the mechanisms
accelerating galactic CR hadrons and electrons are the same, we derive simple
and successful relations between the spectral indices of the GBR above a few
MeV, and of the CR electrons and CR nuclei above a few GeV. We reproduce the
observed intensity and angular dependence of the GBR, in directions away from
the galactic disk and centre, without recourse to hypothetical extragalactic
sources.

</DOC>
<DOC>
<DOCNO> 121926 </DOCNO>
Evolution from Canonical to Millisecond Pulsar through the X-ray


  We model the evolution of canonical pulsars from the death line to
millisecond pulsars through the X-ray neutron star stage of accretion from a
low-mass companion. We trace this evolution in magnetic field strength starting
at $B=10^{12}$ to $10^8$ G and in period of about 1 s to milliseconds.
Important factors are accretion rate and the decay rate of the magnetic field.
A broad swathe is traced in the $B-P$ plane according to the value of these
factors, which represent different conditions of the binary pair. An important
ingredient is the dependence of the stellar moment of inertia on rotation
frequency (time).

</DOC>
<DOC>
<DOCNO> 72078 </DOCNO>
Braided Structure in 4-dimensional conformal Quantum Field Theory


  Higher dimensional conformal QFT possesses an interesting braided structure
which, different from the d=1+1 models, is restricted to the timelike region
and therefore easily escapes euclidean action methods. It lies behind the
spectrum of anomalous dimensions which may be viewed as a kind of substitute
for a missing particle interpretation in the presence of interactions.

</DOC>
<DOC>
<DOCNO> 11262 </DOCNO>
Deformation of the Fermi surface in the extended Hubbard model


  The deformation of the Fermi surface induced by Coulomb interactions is
investigated in the t-t'-Hubbard model. The interplay of the local U and
extended V interactions is analyzed. It is found that exchange interactions V
enhance small anisotropies producing deformations of the Fermi surface which
break the point group symmetry of the square lattice at the Van Hove filling.
This Pomeranchuck instability competes with ferromagnetism and is suppressed at
a critical value of U(V). The interaction V renormalizes the t' parameter to
smaller values what favours nesting. It also induces changes on the topology of
the Fermi surface which can go from hole to electron-like what may explain
recent ARPES experiments.

</DOC>
<DOC>
<DOCNO> 170738 </DOCNO>
Theoretical efficient high capacity Quantum Key Distribution Scheme


  A theoretical quantum key distribution scheme using EPR pairs is presented.
This scheme is efficient in that it uses all EPR pairs in distributing the key
except those chosen for checking eavesdroppers. The high capacity is achieved
because each EPR pair carries 2 bits of key code.

</DOC>
<DOC>
<DOCNO> 14034 </DOCNO>
Comment on stability of atoms and nuclei in multidimensional TeV scale


  We discuss the stability of atoms and nucleons in the presence of
multidimensional gravity characterized by the unified energy scale 1TeV. We
point out that the multidimensional gravitational attraction can create
additional bound states deep inside of atomic and nucleon constituents. These
states would be characterized by sizes comparable to the TeV scale distance. We
show that shallow gravity induced bound states between an electron and a quark
are ruled out, because collapse processes in atoms to such bound states would
occur on time scales which are in contradiction to current data on the
stability of ordinary matter. The gravitational attraction may also produce
diquark states, which should be considered in addition to those discussed in
the literature. The estimates indicate that, for TeV scale gravity, the problem
of UV divergencies and UV renormalization is crucial. Some universal
renormalization mechanism should exist, which stabilizes atoms in the presence
of multidimensional gravity.

</DOC>
<DOC>
<DOCNO> 8777 </DOCNO>
Debye screening and Meissner effect in a three-flavor color


  I compute the gluon self-energy in a color superconductor with three flavors
of massless quarks, where condensation of Cooper pairs breaks the color and
flavor SU(3)_c x U(3)_V x U(3)_A symmetry of QCD to the diagonal subgroup
SU(3)_{c+V}. At zero temperature, all eight electric gluons obtain a Debye
screening mass, and all eight magnetic gluons a Meissner mass. The Debye as
well as the Meissner masses are found to be equal for the different gluon
colors. These masses determine the coefficients of the kinetic terms in the
effective theory for the low-energy degrees of freedom. Their values agree with
those obtained by Son and Stephanov.

</DOC>
<DOC>
<DOCNO> 152086 </DOCNO>
Random graph gauge theories as toy models for non-perturbative string


  We present simple models which exhibit some of the remarkable features
expected to hold for the as yet unknown non-perturbative formulation of string
theories. Among these are: (a) the absence of a background or embedding space
for the full theory; (b) perturbative ground states (local minima of the
action) having the characteristics of spaces of different dimension; (c)
duality transformations between large- and small-coupling expansions; and (d)
perturbative excitations of these ground states which can be interpreted as
string worldsheets or p-brane worldvolumes. In this context we formulate gauge
theories on arbitrary graphs and speculate concerning actions for graphs which
in a continuum and/or thermodynamic limit might be related to the
Einstein-Hilbert action.

</DOC>
<DOC>
<DOCNO> 100790 </DOCNO>
Ergodicity of Mapping Class Group Actions on Representation Varieties,


  We prove that the mapping class group of a closed surface acts ergodically on
connected components of the representation variety corresponding to a connected
compact Lie group.

</DOC>
<DOC>
<DOCNO> 101637 </DOCNO>
Quantaloids Describing Causation and Propagation of Physical Properties


  A general principle of `causal duality' for physical systems, lying at the
base of representation theorems for both compound and evolving systems, is
proved; formally it is encoded in a quantaloidal setting. Other particular
examples of quantaloids and quantaloidal morphisms appear naturally within this
setting; as in the case of causal duality, they originate from primitive
physical reasonings on the lattices of properties of physical systems.
Furthermore, an essentially dynamical operational foundation for studying
physical systems is outlined; complementary as it is to the existing static
operational foundation, it leads to the natural axiomatization of `causal
duality' in operational quantum logic.

</DOC>
<DOC>
<DOCNO> 118178 </DOCNO>
Chemistry in the Envelopes around Massive Young Stars


  Recent observational studies of intermediate- and high-mass star-forming
regions at submillimeter and infrared wavelengths are reviewed, and chemical
diagnostics of the different physical components associated with young stellar
objects are summarized. Procedures for determining the temperature, density and
abundance profiles in the envelopes are outlined. A detailed study of a set of
infrared-bright massive young stars reveals systematic increases in the
gas/solid ratios, the abundances of evaporated molecules, and the fraction of
heated ices with increasing temperature. Since these diverse phenomena involve
a range of temperatures from < 100 K to 1000 K, the enhanced temperatures must
be communicated to both the inner and outer parts of the envelopes. This
`global heating' plausibly results from the gradual dispersion of the envelopes
with time. Similarities and differences with low-mass YSOs are discussed. The
availability of accurate physical models will allow chemical models of ice
evaporation followed by `hot core' chemistry to be tested in detail.

</DOC>
<DOC>
<DOCNO> 170083 </DOCNO>
A necessary and sufficient criterion for multipartite separable states


  We present a necessary and sufficient condition for the separability of
multipartite quantum states, this criterion also tells us how to write a
multipartite separable state as a convex sum of separable pure states. To work
out this criterion, we need to solve a set of equations, actually it is easy to
solve these quations analytically if the density matrix of the given quantum
state has few nonzero eigenvalues.

</DOC>
<DOC>
<DOCNO> 80952 </DOCNO>
Recent Progress of Lattice QCD in China


  Lattice QCD is the most reliable non-perturbative method in quantum field
theory. In the last few years, some problems crucial to high energy experiments
have been solved. We review some recent work done by the Chinese lattice
community.

</DOC>
<DOC>
<DOCNO> 116734 </DOCNO>
Black Holes From Different Perspectives


  In this paper we consider black holes from a non general relativistic
perspective as also from a microphysical point of view.

</DOC>
<DOC>
<DOCNO> 9593 </DOCNO>
Reaction-Diffusion Models describing a Two-Lane Traffic Flow


  A uni-directional two-lane road is approximated by a set of two parallel
closed one-dimensional chains. Two types of car i.e. slow and fast ones are
considered in the system. Based on the Nagel-Schreckenberg (Na-Sch) model of
traffic flow, a set of reaction-diffusion processes are introduced to simulate
the behaviour of the cars. Fast cars can pass the slow ones using the
passing-lane. We write and solve the mean field rate equations for the density
of slow and fast cars respectively. We also investigate the properties of the
model through computer simulations and obtain the fundamental diagrams . A
comparison between our results and v_max=2 version of Na-Sch model is made.

</DOC>
<DOC>
<DOCNO> 40455 </DOCNO>
Four-Neutrino Oscillations at SNO


  We discuss the potential of SNO to constraint the four-neutrino mixing
schemes favoured by the results of all neutrino oscillations experiments. These
schemes allow simultaneous transitions of solar $\nu_e's$ into active
$\nu_\mu$'s, $\nu_\tau$'s and sterile $\nu_s$ controlled by the additional
parameter $\cos^2(\vartheta_{23}) \cos^2(\vartheta_{24})$ and they contain as
limiting cases the pure $\nu_e$-active and $\nu_e$-sterile neutrino
oscillations. We first obtain the solutions allowed by the existing data in the
framework of the BP00 standard solar model and quantify the corresponding
predictions for the CC and the NC/CC event ratios at SNO for the different
allowed regions as a function of the active-sterile admixture. Our results show
that some information on the value of $\cos^2(\vartheta_{23})
\cos^2(\vartheta_{24})$ can be obtained by the first SNO measurement of the CC
ratio, while considerable improvement on the knowledge of this mixing will be
achievable after the measurement of the NC/CC ratio.

</DOC>
<DOC>
<DOCNO> 68684 </DOCNO>
On Supersymmetry Breaking in String Theory and its Realization in Brane


  We use string duality to describe instanton induced spontaneous supersymmetry
breaking in string compactifications with additional background fields.
Dynamical supersymmetry breaking by space-time instantons in the heterotic
string theory is mapped to a tree level breaking in the type II string which
can be explicitly calculated by geometric methods. It is argued that the
instanton corrections resurrect the no-go theorem on partial supersymmetry
breaking. The point particle limit describes the non-perturbative scalar
potential of a SYM theory localized on a hypersurface of space-time. The N=0
vacuum displays condensation of magnetic monopoles and confinement. The
supersymmetry breaking scale is determined by $M_{str}$, which can be in the
TeV range, and the geometry transverse to the gauge theory.

</DOC>
<DOC>
<DOCNO> 120486 </DOCNO>
BeppoSAX Observations of the Galactic Center Region: Soft x-rays from


  The BeppoSAX satellite performed a survey of the Galactic Center Region in
the 1-10 keV energy band with its Narrow Field Instruments. Several bright
X-ray sources containing neutron stars and black holes have been observed and
studied, including the possible counterpart of SgrA*. Here we report the
results on the diffuse emission coming from the SgrA Complex. The emission from
within 8 arcmin from SgrA* has a double-temperature thermal spectrum (kT1~0.6
keV and kT2~8 keV) and an energy-dependent morphology: the hard emission (5-10
keV) is elongated along the galactic plane, while the soft one (2-5 keV) shows
a triangular shape, very similar to the radio halo of SgrAEast. This spatial
correlation and the physical parameters of the lower temperature component
support the interpretation of the radio halo of the Sgr~A~East shell as a SNR.

</DOC>
<DOC>
<DOCNO> 68200 </DOCNO>
The eta' and the topological charge density


  We compare two different frameworks which have been proposed to include the
eta' in chiral perturbation theory. The equivalence of these two approaches is
shown both for the purely mesonic case and in the presence of the ground state
baryon octet. The relation between the different sets of parameters in both
Lagrangians is clarified.

</DOC>
<DOC>
<DOCNO> 122325 </DOCNO>
The Cosmic Background Radiation circa nu2K


  We describe the implications of cosmic microwave background (CMB)
observations and galaxy and cluster surveys of large scale structure (LSS) for
theories of cosmic structure formation, especially emphasizing the recent
Boomerang and Maxima CMB balloon experiments. The inflation-based cosmic
structure formation paradigm we have been operating with for two decades has
never been in better shape. Here we primarily focus on a simplified inflation
parameter set, {omega_b,omega_{cdm},Omega_{tot}, Omega_\Lambda,n_s,\tau_C,
\sigma_8}. Combining all of the current CMB+LSS data points to the remarkable
conclusion that the local Hubble patch we can access has little mean curvature
(Omega_{tot}=1.08\pm 0.06) and the initial fluctuations were nearly scale
invariant (n_s=1.03\pm 0.08), both predictions of (non-baroque) inflation
theory. The baryon density is found to be slightly larger than that preferred
by independent Big Bang Nucleosynthesis estimates (omega_b=0.030\pm 0.005 cf.
0.019\pm 0.002). The CDM density is in the expected range (omega_{cdm}=0.17 \pm
0.02). Even stranger is the CMB+LSS evidence that the density of the universe
is dominated by unclustered energy akin to the cosmological constant
(Omega_\Lambda=0.66\pm 0.06), at the same level as that inferred from high
redshift supernova observations. We also sketch the CMB+LSS implications for
massive neutrinos.

</DOC>
<DOC>
<DOCNO> 100193 </DOCNO>
Ray Singer Analytic Torsion of Calabi Yau manifolds I


  In this paper we generalized the variational formulas for the determinants of
the Laplacians on functions of CY metrics to forms of type (0,q) on CY
manifolds. We also computed the Ray Singer Analytic torsion on CY manifolds we
proved that it is bounded by a constant. In case of even dimensional CY
manifolds the Ray Singer Analytic torsion is zero. The interesting case is the
odd dimensional one.

</DOC>
<DOC>
<DOCNO> 118084 </DOCNO>
Spherical, Oscillatory $\alpha^2$-Dynamo Induced by Magnetic Coupling


  A two-layer spherical $\alpha^2$-dynamo model consisting of an inner
electrically conducting core (magnetic diffusivity $\lambda_i$ and radius
$r_i$) with $\alpha = 0$ surrounded by an electrically conducting spherical
shell (magnetic diffusivity $\lambda_o$ and radius $r_o$) with a constant
$\alpha$ is shown to exhibit oscillatory behavior for values of $\beta =
\lambda_i/\lambda_o$ and $r_i/r_o$ relevant to the solar dynamo. Time-dependent
dynamo solutions require $r_i/r_o \geq 0.55$ and $\beta \leq O(1)$. For the
Sun, $r_i/r_o$ is about 0.8 and $\beta\approx 10^{-3}$. The time scale of the
oscillations matches the 22 year period of the sunspot cycle for $\lambda_0 =
O(10^2 km^2 s^{-1}$). It is unnecessary to hypothesize an $\alpha\omega$-dynamo
to obtain oscillatory dynamo solutions; an $\alpha^2$-dynamo suffices provided
the spherical shell region of dynamo action lies above a large, less
magnetically diffusive core, as is the case for the solar dynamo.

</DOC>
<DOC>
<DOCNO> 70183 </DOCNO>
Results from an Algebraic Classification of Calabi-Yau Manifolds


  We present results from an inductive algebraic approach to the systematic
construction and classification of the `lowest-level' CY3 spaces defined as
zeroes of polynomial loci associated with reflexive polyhedra, derived from
suitable vectors in complex projective spaces. These CY3 spaces may be sorted
into `chains' obtained by combining lower-dimensional projective vectors
classified previously. We analyze all the 4242 (259, 6, 1) two- (three-, four-,
five-) vector chains, which have, respectively, K3 (elliptic, line-segment,
trivial) sections, yielding 174767 (an additional 6189, 1582, 199) distinct
projective vectors that define reflexive polyhedra and thereby CY3 spaces, for
a total of 182737. These CY3 spaces span 10827 (a total of 10882) distinct
pairs of Hodge numbers h_11, h_12. Among these, we list explicitly a total of
212 projective vectors defining three-generation CY3 spaces with K3 sections,
whose characteristics we provide.

</DOC>
<DOC>
<DOCNO> 119391 </DOCNO>
Reflected Iron Line From a Source Above a Kerr Black Hole Accretion Disc


  In this paper we present a fully relativistic approach to modelling both the
continuum emission and the reflected fluorescent iron line from a primary X-ray
source near a Kerr black hole. The X-ray source is located above an accretion
disc orbiting around the black hole. The source is assumed to be a static point
source located on an arbitrary position above the disc, on or off the axis of
rotation. We carry out Monte Carlo simulations in order to estimate the iron
line spectrum as well as its equivalent width. Because of the gravitational
lensing effect, an enhancement of the iron line is expected when the primary
source is located close to the central black hole. We find that for a source
located on the axis of rotation the enhancement is relatively modest. An
observer at inclination 30 degrees would measure an equivalent width of ~300eV
in the extreme case of a maximally rotating black hole and a source located at
height 1.5 gravitational radius from the centre. This corresponds to an
equivalent width enhancement factor of about 2 compared to the classical value
where no lensing effect comes into play. However, when allowing the source to
be located off the axis of rotation, much stronger enhancement can be obtained.
In the extreme case of a maximally rotating black hole and a source located
just above the approaching side of the disc, an observer at inclination 30d
egrees could measure an equivalent width as high as ~1.5 keV (i.e. ~10 times
the classical value). We also find that observers located at high inclination
angles observe a stronger line than observers at low inclination angles.

</DOC>
<DOC>
<DOCNO> 151783 </DOCNO>
AdS/CFT Duality and Conformality for Non-Abelian Manifold


  An outline of the conformality approach to the gauge hierarchy is given
including the use of non-abelian orbifolds to give unified models of the
left-right type.

</DOC>
<DOC>
<DOCNO> 122728 </DOCNO>
Cosmic ray composition and energy spectrum above 1 TeV: direct and EAS


  The most recent experimental results on the cosmic ray composition and energy
spectrum above 1 TeV are reviewed and discussed. All data agree on the presence
of the so-called ``knee'' at an energy E(knee) = 3-4 PeV; the knee is seen in
all the components of the Extensive Air Showers. These results support the
hypothesis of an astrophysical origin of the knee, while no new features in the
hadronic interactions at high energies are envisaged. The cosmic ray
composition below and above the knee region is still an open question.
According to most experiments, the knee seems to be due to the light component
of the primary beam, with a composition getting heavier above the knee.
However, results contradicting this conclusion have to be considered and
understood.

</DOC>
<DOC>
<DOCNO> 68944 </DOCNO>
tau -> omega3pinu Decays


  Theoretical study of anomalous decay mode tau -> omega3pinu is presented.

</DOC>
<DOC>
<DOCNO> 83368 </DOCNO>
One-Dimensional Peg Solitaire, and Duotaire


  We solve the problem of one-dimensional Peg Solitaire. In particular, we show
that the set of configurations that can be reduced to a single peg forms a
regular language, and that a linear-time algorithm exists for reducing any
configuration to the minimum number of pegs.
  We then look at the impartial two-player game, proposed by Ravikumar, where
two players take turns making peg moves, and whichever player is left without a
move loses. We calculate some simple nim-values and discuss when the game
separates into a disjunctive sum of smaller games. In the version where a
series of hops can be made in a single move, we show that neither the
P-positions nor the N-positions (i.e. wins for the previous or next player) are
described by a regular or context-free language.

</DOC>
<DOC>
<DOCNO> 122966 </DOCNO>
Discovery of Five Binary Radio Pulsars


  We report on five binary pulsars discovered in the Parkes multibeam Galactic
plane survey. All of the pulsars are old, with characteristic ages 1-11 Gyr,
and have relatively small inferred magnetic fields, 5-90e8 G. The orbital
periods range from 1.3 to 15 days. As a group these objects differ from the
usual low-mass binary pulsars (LMBPs): their spin periods of 9-88 ms are
relatively long; their companion masses, 0.2-1.1 Msun, are, in at least some
cases, suggestive of CO or more massive white dwarfs; and some of the orbital
eccentricities, 1e-5 < e < 0.002, are unexpectedly large. We argue that these
observed characteristics reflect binary evolution that is significantly
different from that of LMBPs. We also note that intermediate-mass binary
pulsars apparently have a smaller scale-height than LMBPs.

</DOC>
<DOC>
<DOCNO> 117315 </DOCNO>
Causal explanation for observed superluminal behavior of microwave


  In this paper we present a theoretical analysis of an experiment by Mugnai
and collaborators where superluminal behavior was observed in the propagation
of microwaves. We suggest that what was observed can be well approximated by
the motion of a superluminal X wave. Furthermore the experimental results are
also explained by the so called scissor effect which occurs with the
convergence of pairs of signals coming from opposite points of an annular
region of the mirror and forming an interference peak on the intersection axis
traveling at superluminal speed. We clarify some misunderstandings concerning
this kind of electromagnetic wave propagation in vacuum.

</DOC>
<DOC>
<DOCNO> 13705 </DOCNO>
Vortex nucleation and hysteresis phenomena in rotating Bose-Einstein


  We study the generation of vortices in rotating Bose--Einstein condensates, a
situation which has been realized in a recent experiment (K. W. Madison, F.
Chevy, W. Wohlleben, J. Dalibard, Phys. Rev. Lett. {\bf 84} 806 (2000)). By
combining a linear stability analysis with the global optimization of the
nonlinear free energy functional, we study the regimes that can be reached in
current experiments. We find a hysteresis phenomenon in the vortex nucleation
due to the metastabilization of the vortexless condensate. We also prove that
for a fast enough rotating trap the ground state of the condensate hosts one or
more bent vortex lines.

</DOC>
<DOC>
<DOCNO> 9685 </DOCNO>
Photogalvanic Effects in Heteropolar Nanotubes


  We show that an electrical shift current is generated when electrons are
photoexcited from the valence to conduction bands on a BN nanotube. This
photocurrent follows the light pulse envelope and its symmetry is controlled by
the atomic structure of the nanotube. We find that the shift current has an
intrinsic quantum mechanical signature in which the chiral index of the tube
determines the direction of the current along the tube axis. We identify
discrete lattice effects in the tangent plane of the tube that lead to an
azimuthal component of the shift current. The nanotube shift current can lead
to ultrafast opto-electronic and opto-mechanical applications.

</DOC>
<DOC>
<DOCNO> 117343 </DOCNO>
Magnetic field effects on the thermonuclear combustion front of


  The explosion of a type Ia supernova starts in a white dwarf as a laminar
deflagration at the center of the star and soon several hydrodynamic
instabilities, in particular, the Rayleigh-Taylor instability, begin to act. A
cellular stationary combustion and a turbulent combustion regime are rapidly
achieved by the flame and maintained up to the end of the so-called flamelet
regime when the transition to detonation is believed to occur. The burning
velocity at these regimes is well described by the fractal model of combustion.
Using a semi-analytic approach, we describe the effect of magnetic fields on
the fractalization of the front considering a white dwarf with a nearly dipolar
magnetic field. We find an intrinsic asymmetry on the velocity field that may
be maintained up to the free expansion phase of the remnant. Considering the
strongest values inferred for a white dwarf's magnetic fields with strengths up
to $10^{8}-10^{9}$ G at the surface and assuming that the field near the centre
is roughly 10 times greater, asymmetries in the velocity field higher than
$10-20 %$ are produced between the magnetic polar and the equatorial axis of
the remnant which may be related to the asymmetries found from recent
spectropolarimetric observations of very young SN Ia remnants. Dependence of
the asymmetry with white dwarf composition is also analyzed.

</DOC>
<DOC>
<DOCNO> 117195 </DOCNO>
Spontaneous formation and stability of small GaP fullerenes


  We report the spontaneous formation of a GaP fullerene cage in ab-initio
Molecular Dynamics simulations starting from a bulk fragment. A systematic
study of the geometric and electronic properties of neutral and ionized GaP
clusters suggests the stability of hetero-fullerenes formed by a compound with
zincblend bulk structure. We find that GaP fullerenes up to 28 atoms have high
symmetry, closed electronic shells, large HOMO-LUMO energy gaps and do not
dissociate when ionized. We compare our results for GaP with those obtained by
other groups for the corresponding BN clusters.

</DOC>
<DOC>
<DOCNO> 12443 </DOCNO>
Spectroscopic Evidence for the Localization of Skyrmions near Nu=1 as


  Optically pumped nuclear magnetic resonance measurements of Ga-71 spectra
were carried out in an n-doped GaAs/Al0.1Ga0.9As multiple quantum well sample
near the integer quantum Hall ground state Nu=1. As the temperature is lowered
(down to T~0.3 K), a ``tilted plateau'' emerges in the Knight shift data, which
is a novel experimental signature of quasiparticle localization. The dependence
of the spectra on both T and Nu suggests that the localization is a collective
process. The frozen limit spectra appear to rule out a 2D lattice of
conventional skyrmions.

</DOC>
<DOC>
<DOCNO> 11623 </DOCNO>
Two Simple Approaches to Sol-Gel Transition


  We represent a theory of polymer gelation as an analogue of liquid-glass
transition in which elastic fields of stress and strain shear components appear
spontaneously as a consequence of the cross-linking of macromolecules. This
circumstance is explained on the basis of obvious combinatoric arguments as
well as a synergetic Lorenz system, where the strain acts as an order
parameter, a conjugate field is reduced to the elastic stress, and the number
of cross-links is a control parameter. Both the combinatoric and synergetic
approaches show that an anomalous slow dependence of the shear modulus on the
number of cross-links is obtained.

</DOC>
<DOC>
<DOCNO> 101747 </DOCNO>
Exact Wigner surmise type evaluation of the spacing distribution in the


  Random matrix ensembles with orthogonal and unitary symmetry correspond to
the cases of real symmetric and Hermitian random matrices respectively. We show
that the probability density function for the corresponding spacings between
consecutive eigenvalues can be written exactly in the Wigner surmise type form
$a(s) e^{-b(s)}$ for $a$ simply related to a Painlev\'e transcendent and $b$
its anti-derivative. A formula consisting of the sum of two such terms is given
for the symplectic case (Hermitian matrices with real quaternion elements).

</DOC>
<DOC>
<DOCNO> 84629 </DOCNO>
Black holes and closed trapped surfaces: a revision of a classic theorem


  It is standard assertion in relativity that, subject to an energy condition
and the cosmic censorship hypothesis, closed trapped surfaces are not visible
from future null infinity. A proof given by Hawking & Ellis in ''The Large
Scale Structure of Space-Time'' is flawed since it is formulated in terms of an
inadequate definition of a weakly asymptotically simple and empty space-time. A
new proof is given based on a more restrictive definition of a weakly
asymptotically simple and empty space-time.

</DOC>
<DOC>
<DOCNO> 152368 </DOCNO>
Nonlinear Realization of Lorentz Symmetry


  We explore a nonlinear realization of the (2+1)-dimensional Lorentz symmetry
with a constant vacuum expectation value of the second rank anti-symmetric
tensor field. By means of the nonlinear realization, we obtain the low-energy
effective action of the Nambu-Goldstone bosons for the spontaneous Lorentz
symmetry breaking.

</DOC>
<DOC>
<DOCNO> 13160 </DOCNO>
Comparing the correlation length of grain markets in China and France


  In economics comparative analysis plays the same role as experimental
research in physics. In this paper we closely examine several methodological
problems related to comparative analysis by investigating the specific example
of grain markets in China and France respectively. This enables us to answer a
question in economic history which has so far remained pending, namely whether
or not market integration progressed in the 18th century. In economics as in
physics, before being accepted any new result has to be checked and re-checked
by different researchers. This is what we call the replication and comparison
procedures. We show how these procedures should (and can) be implemented.

</DOC>
<DOC>
<DOCNO> 10908 </DOCNO>
Zero-bias transport anomaly in metallic nanobridges: Magnetic field


  We present data of transport measurements through a metallic nanobridge
exhibiting diffusive electron transport. A logarithmic temperature dependence
and a zero-bias anomaly in the differential conductance are observed,
independent of magnetic field. The data can be described by a single scaling
law. The theory of electron-electron interaction in disordered systems, adapted
to the case of finite-size systems in non-equilibrium, yields quantitative
agreement with experiment. Measurements of universal conductance functuations
support the assumptions of the theory about the electronic phase coherence.

</DOC>
<DOC>
<DOCNO> 10863 </DOCNO>
Simulational Study on Dimensionality-Dependence of Heat Conduction


  Heat conduction phenomena are studied theoretically using computer
simulation. The systems are crystal with nonlinear interaction, and fluid of
hard-core particles. Quasi-one-dimensional system of the size of $L_x\times
L_y\times L_z(L_z\gg L_x,L_y)$ is simulated. Heat baths are put in both end:
one has higher temperature than the other. In the crystal case, the interaction
potential $V$ has fourth-order non-linear term in addition to the harmonic
term, and Nose-Hoover method is used for the heat baths. In the fluid case,
stochastic boundary condition is charged, which works as the heat baths.
Fourier-type heat conduction is reproduced both in crystal and fluid models in
three-dimensional system, but it is not observed in lower dimensional system.
Autocorrelation function of heat flux is also observed and long-time tails of
the form of $\sim t^{-d/2}$, where $d$ denotes the dimensionality of the
system, are confirmed.

</DOC>
<DOC>
<DOCNO> 70504 </DOCNO>
Comment on ``Neutrino oscillations in the early universe: how can large


  We comment on the recent paper by A. D. Dolgov, S. H. Hansen, S. Pastor and
D. V. Semikoz (DHPS) [Astropart. Phys. {\bf 14}, 79 (2000)] on the generation
of neutrino asymmetries from active-sterile neutrino oscillations. We
demonstrate that the approximate asymmetry evolution equation obtained therein
is an expansion, up to a minor discrepancy, of the well-established static
approximation equation, valid only when the supposedly new higher order
correction term is small. In the regime where this so-called ``back-reaction''
term is large and artificially terminates the asymmetry growth, their evolution
equation ceases to be a faithful approximation to the Quantum Kinetic Equations
(QKEs) simply because pure Mikheyev-Smirnov-Wolfenstein (MSW) transitions have
been neglected. At low temperatures the MSW effect is the dominant asymmetry
amplifier. Neither the static nor the DHPS approach contains this important
physics. Therefore we conclude that the DHPS results have sufficient veracity
at the onset of explosive asymmetry generation, but are invalid in the ensuing
low temperature epoch where MSW conversions are able to enhance the asymmetry
to values of order $0.2 - 0.37$. DHPS do claim to find a significant final
asymmetry for very large $\delta m^2$ values. However, for this regime the
effective potential they employed is not valid.

</DOC>
<DOC>
<DOCNO> 151482 </DOCNO>
Unusual Bound States in QFT Models


  Homogeneous Bethe-Salpeter equation for simplest Wick-Cutkosky model is
studied in the case when the mass of the two-body system is more then the sum
of constituent particles masses. It is shown that there is always a small
attraction between the like-sigh charged particles as a pure relativistic
effect. If the coupling constant exceeds some critical values there arise
discrete levels.The situation here is analogous to the so-called "abnormal"
solutions.The signature of the norm of these discrete states coincides with the
"time-parity".The states with the negative norms can be excluded from the
physical sector-the one-time (quasipotential) wave-function corresponding to
them vanishes identically.However the positive norm states survive and
contribute to the total Green function (and the S-matrix) with the proper sign.

</DOC>
<DOC>
<DOCNO> 101131 </DOCNO>
Some irreducible free group representations in which a linear


  We construct irreducible unitary representations of a finitely generated free
group which are weakly contained in the left regular representation and in
which a given linear combination of the generators has an eigenvalue. When the
eigenvalue is specified, we conjecture that there is only one such
representation. The representation we have found is described explicitly
(modulo inversion of a certain rational map on euclidean space) in terms of a
positive definite function, and also by means of a quasi-invariant probability
measure on the combinatorial boundary of the group.

</DOC>
<DOC>
<DOCNO> 7858 </DOCNO>
d_{x^2-y^2} pairing of composite excitations in the 2D Hubbard model


  We report on a strong coupling approach (on-site Coulomb repulsion, U larger
than the nearest-neighbour hopping energy |t|) to the Hubbard model. Starting
from the Hubbard operators which diagonalize the interaction term, we generate
a hierarchy of composite operators from the equations of motion. Using the
Hubbard operators as a basis, we are able to compute the associated Green
functions including the anomalous Green functions which describe pair
formation. We show explicitly that these anomalous Green functions are non-zero
in the d_{x^2-y^2} channel; however, the entities that pair up are not single
electron-like particles but rather composite excitations (which we call cexons)
made out of an electron and a hole on nearest-neighbour sites. Cexons are
fermionic in nature as they have spin 1/2 and also have unit charge. Our
calculations of the chemical potential reveal that negative compressibility in
the 2D Hubbard model and composite excitation pairing are intimately connected,
namely, the larger the negative compressibility, the larger the pairing
amplitude. Our observation of negative compressibility in the under-doped
regime is consistent with phase segregation or stripe formation in the normal
state. While pairing ameliorates the negative compresssibility, it does not
eliminate it entirely. In addition, we find that the anomalous correlation
functions are particle-hole symmetric and exhibit a maximum at a doping level
of roughly 10% as measured from half-filling. For U=8|t|, the onset temperature
for pair formation is 0.02|t|.

</DOC>
<DOC>
<DOCNO> 118290 </DOCNO>
Correlated intense X-ray and TeV activity of Mrk~501 in 1998 June


  We present exactly simultaneous X-ray and TeV monitoring with {\it RXTE} and
HEGRA of the TeV blazar Mrk 501 during 15 days in 1998 June. After an initial
period of very low flux at both wavelengths, the source underwent a remarkable
flare in the TeV and X-ray energy bands, lasting for about six days and with a
larger amplitude at TeV energies than in the X-ray band. At the peak of the TeV
flare, rapid TeV flux variability on sub-hour timescales is found. Large
spectral variations are observed at X-rays, with the 3--20 keV photon index of
a pure power law continuum flattening from $\Gamma=2.3$ to $\Gamma=1.8$ on a
timescale of 2--3 days. This implies that during the maximum of the TeV
activity, the synchrotron peak shifted to energies $\gtrsim 50$ keV, a behavior
similar to that observed during the longer-lasting, more intense flare in 1997
April. The TeV spectrum during the flare is described by a power law with
photon index $\Gamma=1.9$ and an exponential cutoff at $\sim$ 4 TeV; an
indication for spectral softening during the flare decay is observed in the TeV
hardness ratios. Our results generally support a scenario where the TeV photons
are emitted via inverse Compton scattering of ambient seed photons by the same
electron population responsible for the synchrotron X-rays. The simultaneous
spectral energy distributions (SEDs) can be fit with a one-zone
synchrotron-self Compton model assuming a substantial increase of the magnetic
field and the electron energy by a factor of 3 and 10, respectively.

</DOC>
<DOC>
<DOCNO> 119129 </DOCNO>
Global Nonradial Instabilities of Dynamically Collapsing Gas Spheres


  Self-similar solutions provide good descriptions for the gravitational
collapse of spherical clouds or stars when the gas obeys a polytropic equation
of state, $p=K\rho^\gamma$ (with $\gamma\le 4/3$). We study the behaviors of
nonradial perturbations in the similarity solutions of Larson, Penston and
Yahil, which describe the evolution of the collapsing cloud prior to core
formation. Our global stability analysis reveals the existence of unstable
bar-modes ($l=2$) when $\gamma\le 1.09$. In particular, for the collapse of
isothermal spheres, which applies to the early stages of star formation, the
$l=2$ density perturbation relative to the background, $\delta\rho({\bf
r},t)/\rho(r,t)$, increases as $(t_0-t)^{-0.352}\propto \rho_c(t)^{0.176}$,
where $t_0$ denotes the epoch of core formation, and $\rho_c(t)$ is the cloud
central density. Thus, the isothermal cloud tends to evolve into an ellipsoidal
shape (prolate bar or oblate disk, depending on initial conditions) as the
collapse proceeds. In the context of Type II supernovae, core collapse is
described by the $\gamma\simeq 1.3$ equation of state, and our analysis
indicates that there is no growing mode (with density perturbation) in the
collapsing core before the proto-neutron star forms, although nonradial
perturbations can grow during the subsequent accretion of the outer core and
envelope onto the neutron star. We also carry out a global stability analysis
for the self-similar expansion-wave solution found by Shu, which describes the
post-collapse accretion (``inside-out'' collapse) of isothermal gas onto a
protostar. We show that this solution is unstable to perturbations of all
$l$'s, although the growth rates are unknown.

</DOC>
<DOC>
<DOCNO> 122499 </DOCNO>
High resolution spectroscopy of symbiotic stars. VI. Orbital and stellar


  We present new dynamical parameters of the AR Pav binary system.
Ourobservations consist of a series of high resolution optical/NIR spectra from
which we derive the radial velocity curve of the red giant as well as its
rotation velocity. Assuming co-rotation, we determine the stellar radius (130
R_solar) of the red giant. Based on this we derive the red giant's luminosity
and mass (2.0 M_solar) as well as the distance of the system (4.9 kpc). The
binary mass function finally yields the companion's mass (0.75 M_solar) and the
binary separation (1.95 AU). We find that the red giant does not fill its Roche
lobe. We review the radial velocity data of Thackeray and Hutchings (1974), and
compare it with our red giant's orbit. We find that their RV curves of the blue
absorption system and the permitted emission lines are in anti-phase with the
red giant, and that the forbidden emission lines are shifted by a quarter of a
period. The blue absorptions and the permitted emission lines are associated
with the hot companion but not in a straightforward way. The blue absorption
system only tracks the hot component's orbital motion whilst it is in front of
the red giant, whereas at other phases line blanketing by interbinary material
leads to perturbations. We finally present UV light curves based on IUE archive
spectra. We clearly detect eclipses in the continuum at all wavelengths. The
eclipse light curves are unusual in that they show a slow and gradual decline
prior to eclipse which is followed by a sharp increase after eclipse.

</DOC>
<DOC>
<DOCNO> 13985 </DOCNO>
Nonlinear response and scaling law in the vortex state of d-wave


  We study the field dependence of the quasi-particle density of states, the
thermodynamics and the transport properties in the vortex state of d-wave
superconductors when a magnetic field is applied perpendicular to the
conducting plane, specially for the low field and the low temperature compared
to the upper critical field and transition temperature, respectively, $H/H_{c2}
\ll 1$ and $T/T_c \ll 1$. Both the superfluid density and the spin
susceptibility exhibit the characteristic $\sqrt{H}$-field dependence, while
the nuclear spin lattice relaxation rate T$_1^{-1}$ and the thermal
conductivity are linear in field $H$. With increasing temperature, these
quantities exhibit the scaling behavior in $T/\sqrt{H}$. The present theory
applies to 2D $f$-wave superconductor as well; a possible candidate of the
superconductivity in Sr$_2$RuO$_4$.

</DOC>
<DOC>
<DOCNO> 99581 </DOCNO>
Energy in Yang-Mills on a Riemann Surface


  Sengupta's lower bound for the Yang-Mills action on smooth connections on a
bundle over a Riemann surface generalizes to the space of connections whose
action is finite. In this larger space the inequality can always be saturated.
The Yang-Mills critical sets correspond to critical sets of the energy action
on a space of paths. This may shed light on Atiyah and Bott's conjecture
concerning Morse theory for the space of connections modulo gauge
transformations.

</DOC>
<DOC>
<DOCNO> 10250 </DOCNO>
Vortex precession in Bose-Einstein condensates: observations with filled


  We have observed and characterized the dynamics of singly quantized vortices
in dilute-gas Bose-Einstein condensates. Our condensates are produced in a
superposition of two internal states of 87Rb, with one state supporting a
vortex and the other filling the vortex core. Subsequently, the state filling
the core can be partially or completely removed, reducing the radius of the
core by as much as a factor of 13, all the way down to its bare value. The
corresponding superfluid rotation rates, evaluated at the core radius, vary by
a factor of 150, but the precession frequency of the vortex core about the
condensate axis changes by only a factor of two.

</DOC>
<DOC>
<DOCNO> 99824 </DOCNO>
Surfaces of Albanese general type and the Severi Conjecture


  In 1932 F. Severi claimed, with an incorrect proof, that every smooth minimal
projective surface $S$ such that the bundle $\Omega^1_S$ is generically
generated by global sections satisfies the topological inequality $2c_1^2(S)\ge
c_2(S)$. According to Enriques-Kodaira classification, the above inequality is
easily verified when the Kodaira dimension of the surface is $\le 1$, while for
surfaces of general type it is still an open problem known as Severi
conjecture. In this paper we prove Severi conjecture under the additional mild
hypothesis that $S$ has ample canonical bundle. Moreover, under the same
assumption, we prove that $2c_1^2(S)=c_2(S)$ if and only if $S$ is a double
cover of an abelian surface.

</DOC>
<DOC>
<DOCNO> 169991 </DOCNO>
Dynamics of multiply charged ions in intense laser fields


  We numerically investigate the dynamics of multiply charged hydrogenic ions
in near-optical linearly polarized laser fields with intensities of order 10^16
to 10^17 W/cm^2. Depending on the charge state Z of the ion the relation of
strength between laser field and ionic core changes. We find around Z=12
typical multiphoton dynamics and for Z=3 tunneling behaviour, however with
clear relativistic signatures. In first order in v/c the magnetic field
component of the laser field induces a Z-dependent drift in the laser
propagation direction and a substantial Z-dependent angular momentum with
repect to the ionic core. While spin oscillations occur already in first order
in v/c as described by the Pauli equation, spin induced forces via spin orbit
coupling only appear in the parameter regime where (v/c)^2 corrections are
significant. In this regime for Z=12 ions we show strong splittings of resonant
spectral lines due to spin-orbit coupling and substantial corrections to the
conventional Stark shift due to the relativistic mass shift while those to the
Darwin term are shown to be small. For smaller charges or higher laser
intensities, parts of the electronic wavepacket may tunnel through the
potential barrier of the ionic core, and when recombining are shown to give
rise to keV harmonics in the radiation spectrum. Some parts of the wavepacket
do not recombine after ionisation and we find very energetic electrons in the
weakly relativistic regime of above threshold ionization.

</DOC>
<DOC>
<DOCNO> 14172 </DOCNO>
Creep motion in a random-field Ising model


  We analyze numerically a moving interface in the random-field Ising model
which is driven by a magnetic field. Without thermal fluctuations the system
displays a depinning phase transition, i.e., the interface is pinned below a
certain critical value of the driving field. For finite temperatures the
interface moves even for driving fields below the critical value. In this
so-called creep regime the dependence of the interface velocity on the
temperature is expected to obey an Arrhenius law. We investigate the details of
this Arrhenius behavior in two and three dimensions and compare our results
with predictions obtained from renormalization group approaches.

</DOC>
<DOC>
<DOCNO> 118742 </DOCNO>
The late afterglow and host galaxy of GRB 990712


  We present deep HST imaging, as well as ground-based imaging and
spectroscopy, of the optical afterglow associated with the long-duration
gamma-ray burst GRB 990712 and its host galaxy. The data were obtained 48--123
days after the burst occurred. The magnitudes of the host (R = 21.9, V = 22.5)
and optical afterglow (R = 25.4, V = 25.8, 47.7 days after the burst) favor a
scenario where the optical light follows a pure power-law decay with an index
of alpha ~ -1.0. We find no evidence for a contribution from a supernova like
SN1998bw. This suggests that either there are multiple classes of long-duration
gamma-ray bursts, or that the peak luminosity of the supernova was > 1.5 mag
fainter than SN1998bw. The HST images and EFOSC2 spectra indicate that the
gamma-ray burst was located in a bright, extended feature (possibly a
star-forming region) 1.4 kpc from the nucleus of a 0.2 L^*_B galaxy at z =
0.434, possibly a Seyfert 2 galaxy. The late-time afterglow and host galaxy of
GRB 990712 bear some resemblance to those of GRB 970508.

</DOC>
<DOC>
<DOCNO> 72230 </DOCNO>
Neutrino Oscillations in Supersymmetry without Lepton number


  With the on-shell renormalization scheme, we discuss neutrino masses up to
one-loop approximation in the Supersymmetry without lepton number conservation
and R-parity. Ii is shown that in this model with experimentally allowed
parameters, $\Delta m^2_{23}, \Delta m^2_{12}$ and the mixing angles
$|\sin\theta{23}|,|\sin\theta_{12}|$ which are consistent with the present
observation values can be produced. We find that small neutrino mass ($\leq$ 1
eV) sets a loose constraint on the R-parity violation parameters in the soft
breaking terms.

</DOC>
<DOC>
<DOCNO> 119776 </DOCNO>
Spectroscopic confirmation of a white dwarf companion to the B star 16


  Using an Extreme Ultraviolet Explorer (EUVE) spectrum, we confirm the
identification of a white dwarf companion to the B9.5V star 16 Dra (HD150100),
and constrain its surface temperature to lie between 29,000K and 35,000K. This
is the third B star + white dwarf non-interacting Sirius-type binary to be
confirmed, after y Pup (HR2875, HD59635) and theta Hya (HR3665, HD79469). 16
Dra and its white dwarf companion are members of a larger resolved proper
motion system including the B9V star 17 Dra A (HD150117). The white dwarf must
have evolved from a progenitor more massive than this star, i.e. ~3.7 solar
masses. White dwarf companions to B stars are important since they set an
observational limit on the maximum mass for white dwarf progenitors, and can
potentially be used to investigate the high mass ends of the initial-final mass
relation and the white dwarf mass-radius relation.

</DOC>
<DOC>
<DOCNO> 10505 </DOCNO>
Jahn-Teller-effect formation of the non-magnetic ground state for the d8


  It is shown that the d8 electron system occurring in the Ni2+ ion can have
the non-magnetic ground state in the atomic scale formed by the Jahn-Teller
effect. The tetragonal/trigonal off-cubic lattice distortion for the octahedral
site causes the splitting of the triplet 3A2g into a singlet-doublet structure
with the non-magnetic singlet lying lower provided the intra-atomic spin-orbit
coupling is taken into account.

</DOC>
<DOC>
<DOCNO> 9384 </DOCNO>
Spatially resolved spectroscopy on a superconducting proximity structure


  We investigated the local density of states (LDOS) of a normal metal (N) in
good electrical contact with a superconductor (S) as a function of the distance
$x$ to the NS interface. The sample consists of a pattern of alternate stripes
of Au and Nb made by UV-lithography. We used a low temperature scanning
tunneling microscope to record simultaneously $dI/dV(V,x)$ curves and the
topographic profile $z(x)$. Nearby the NS interface, all the spectra show a dip
near the Fermi energy but depending on the geometry, different behaviours can
be distinguished. First, when the characteristic size of the normal metal $L$
is much larger than the coherence length $\xi_N \simeq \sqrt{\hbar D_N/
2\Delta}$, the spectral extension of the dip decreases from $\Delta$ at the NS
interface to zero at distances $x\gg\xi_N$. Second, when $L$ is comparable to
$\xi_N$ the apparent gap in the LDOS is space-independent and related to the
Thouless energy.

</DOC>
<DOC>
<DOCNO> 118889 </DOCNO>
Extrapolation of the solar magnetic field within the potential-field


  This paper is concerned with the Laplace boundary-value problem with the
directional derivative, corresponding to the specific nature of measurements of
the longitudinal component of the photospheric magnetic field. Boundary
conditions are specified by a distribution on the sphere of projection of the
magnetic field vector unto a given direction. It is shown that the solution of
this problem exists in the form of a spherical harmonic expansion, and
uniqueness of this solution is proved. A conceptual sketch of numerical
determination of the harmonic series coefficients is given. The field of
application of the method is analyzed having regard to the peculiarities of
actual data. Finally, we present differences in results derived from
extrapolating the magnetic field from a synoptic map and a full-disk
magnetogram.

</DOC>
<DOC>
<DOCNO> 102494 </DOCNO>
A Simple Proof that Rational Curves on K3 are Nodal


  We give a simple proof of the statement that every rational curve in the
primitive class of a general K3 surface is nodal.

</DOC>
<DOC>
<DOCNO> 170683 </DOCNO>
Generation of coherent superposition of Fock states in a cavity.


  A scheme for preparation of coherent superposition of Fock states of
electromagnetic field is constructed. The superposition state is created inside
the cavity via a strong interaction of a four-level atom with quantum field of
the cavity and classic laser fields. We demonstrate the possibility to create
desired arbitrary superposition of the cavity Fock states just by changing the
relative delay of the fields. Then, as another application of our model, we
study a means of creating entanglement of neutral four-level atoms using
different sequences of interactions with the cavity and laser fields.

</DOC>
<DOC>
<DOCNO> 13133 </DOCNO>
Harper Map Phase Diagram from Topological Classification


  Is suggested a \textit{topological} hierarchical classification of the
infinite many Localized phases figuring in the phase diagram of the harper map
for anisotropy parameter $\epsilon$ versus Energy. The magnetic flux is taken
to be the irrational golden mean, $\omega^*=(\sqrt{5}-1)/2$. This system is
equivalent to the semiclassical problem of Bloch electrons in a uniform
magnetic field (Azbel-Hofstadter model). A rule that explain the fractal
structure of the phase diagram is proposed.

</DOC>
<DOC>
<DOCNO> 151789 </DOCNO>
Higher Dimensional Kerr-AdS Black Holes and the AdS/CFT Correspondence


  Using the counterterm subtraction technique we calculatehe stress-energy
tensor, action, and other physical quantities for Kerr-AdS black holes in
various dimensions. For Kerr-AdS_5 with both rotation parameters non-zero, we
demonstrate that stress-energy tensor, in the zero mass parameter limit, is
equal to the stress tensor of the weakly coupled four dimensional dual field
theory. As a result, the total energy of the generalKerr-AdS_5 black hole at
zero mass parameter, exactly matches the Casimir energy of the dual field
theory. We show that at high temperature, the general Kerr-AdS_5 and
perturbative field theory stress-energy tensors are equal, up to the usual
factor of 3/4. We also use the counterterm technique to calculate the stress
tensors and actions for Kerr-AdS_6, and Kerr-AdS_7 black holes, with one
rotation parameter, and we display the results. We discuss the conformal
anomalies of the field theories dual to the Kerr-AdS_5 and Kerr-AdS_7
spacetimes. In these two field theories, we show that the rotation parameters
break conformal invariance but not scale invariance, a novel result for a
non-trivial field theory. For Kerr-AdS_7 the conformal anomalies calculated on
the gravity side and the dual (0,2) tensor multiplet theory are equal up to 4/7
factor. We expect that the Casimir energy of the free field theory is the same
as the energy of the Kerr-AdS_7 black hole (with zero mass parameter), up to
that factor.

</DOC>
<DOC>
<DOCNO> 151880 </DOCNO>
Interaction of higher spin massive fields with gravity in string theory


  Derivations of consistent equations of motion for the massive spin two field
interacting with gravity is reviewed. From the field theoretical point of view
the most general classical action describing consistent causal propagation in
vacuum Einstein spacetime is given. It is also shown that the massive spin two
field can be consistently described in arbitrary background by means of
lagrangian equations representing an infinite series in curvature. Within
string theory equations of motion for the massive spin two field coupled to
gravity is derived from the requirement of quantum Weyl invariance of the
corresponding two dimensional sigma-model. In the lowest order in string length
the effective equations of motion are demonstrated to coincide with the general
form of consistent equations derived in field theory.

</DOC>
<DOC>
<DOCNO> 150831 </DOCNO>
Interacting six-dimensional topological field theories


  We study the gauge-fixing and symmetries (BRST-invariance and vector
supersymmetry) of various six-dimensional topological models involving Abelian
or non-Abelian 2-form potentials.

</DOC>
<DOC>
<DOCNO> 70949 </DOCNO>
Antihyperon-Production in Relativistic Heavy Ion Collision


  Recently it has been shown that the observed antiproton yield in heavy-ion
collisions at CERN-SpS energies can be understood by multi-pionic interactions
which enforce local chemical equilibrium of the antiprotons with the nucleons
and pions. Here we show that antihyperons are driven towards local chemical
equilibrium with pions, nucleons and kaons on a timescale of less than 3 fm/c
when applying a similar argument for the antihyperons by considering the
inverse channel of annihilation reactions anti-Y + p to pions + kaons. These
multi-mesonic reactions easily explain the antihyperon yields at CERN-SpS
energies as advertised in pure thermal, hadronic models without the need of a
quark gluon plasma phase. In addition, the argument also applies for AGS
energies.

</DOC>
<DOC>
<DOCNO> 122905 </DOCNO>
Evolution of Clusters of Galaxies II: Dependence on Initial Cluster


  We investigated the evolution of clusters of galaxies using self-consistent
N-body simulations. We varied the initial model of galaxies and clusters, and
studied the dependence of evolution on initial conditions. We found that the
growth rate of the common halo depends only weakly on galaxy models. On the
other hand, the growth rate depends strongly on cluster models. Initially the
growth rate is higher for cluster models with higher central density. However,
this high growth rate drops in a few crossing times of the cluster, and after
several crossing times, roughly half of the total mass is in the common halo in
all models we considered. In the central region of clusters density cusps with
the profile \rho ~ r^{-1.2} develops regardless of the models of clusters and
galaxies. We also found that the galaxies evolved so as to satisfy the relation
between the masses of galaxies m_{gx} and their velocity dispersion \sigma_{gx}
expressed as m_{gx} \propto \sigma_{gx}^{3~4} for all galaxy models as a
consequence of their dynamical evolution through galaxy-galaxy interactions. We
discuss the relation between our result and the observed Faber-Jackson
relation.

</DOC>
<DOC>
<DOCNO> 117847 </DOCNO>
Accelerations of Water Masers in NGC4258


  The water masers in NGC4258 delineate the structure and dynamics of a
sub-parsec-diameter accretion disk around a supermassive black hole. We report
acceleration measurements for 12 systemic-velocity spectral features and 19
high-velocity spectral features, using a total of 25 epochs of observations
from Effelsberg (5 epochs), the VLA (15 epochs), and the VLBA (5 epochs)
spanning the years 1994 to 1997. The measured accelerations of the
systemic-velocity features are between 7.5 and 10.4 km/s/yr, and there is no
evidence for a dip in the spectrum at the systemic velocity. Such a dip has
been attributed in the past to an absorbing layer of non-inverted H2O (Watson &
Wallin 1994; Maoz & McKee 1998). The accelerations of the high-velocity
features, measured here for the first time, range from -0.77 to 0.38 km/s/yr.
  From the line-of-sight accelerations and velocities, we infer the positions
of these high-velocity masers with a simple edge-on disk model. The resulting
positions fall between -13.6 and 9.3 degrees in azimuth (measured from the
midline, the diameter perpendicular to the line of sight). A model that
suggests a spiral shock origin of the masers (Maoz & McKee 1998), in which
changes in maser velocity are due to the outward motion of the shock wave,
predicts apparent accelerations of -0.05 times theta_p/2.5 degrees km/s/yr,
where theta_p is the pitch angle of the spiral arms. Our data are not
consistent with these predictions. We also discuss the physical properties of
the high-velocity masers. Most notably, the strongest high-velocity masers lie
near the midline, where the velocity gradient is smallest, thereby providing
the longest amplification path lengths. (Abridged)

</DOC>
<DOC>
<DOCNO> 85600 </DOCNO>
Superinflation, quintessence, and nonsingular cosmologies


  The dynamics of a universe dominated by a self-interacting nonminimally
coupled scalar field are considered. The structure of the phase space and
complete phase portraits are given. New dynamical behaviors include
superinflation ($\dot{H}>0$), avoidance of big bang singularities through
classical birth of the universe, and spontaneous entry into and exit from
inflation. This model is promising for describing quintessence as a
nonminimally coupled scalar field.

</DOC>
<DOC>
<DOCNO> 12289 </DOCNO>
The Limits of Information


  Black holes have their own thermodynamics including notions of entropy and
temperature and versions of the three laws. After a light introduction to black
hole physics, I recollect how black hole thermodynamics evolved in the 1970's,
while at the same time stressing conceptual points which were given little
thought at that time, such as why the entropy should be linear in the black
hole's surface area. I also review a variety of attempts made over the years to
provide a statistical mechanics for black hole thermodynamics. Finally, I
discuss the origin of the information bounds for ordinary systems that have
arisen as applications of black hole thermodynamics.

</DOC>
<DOC>
<DOCNO> 11949 </DOCNO>
The dynamical structure factor in topologically disordered systems


  A computation of the dynamical structure factor of topologically disordered
systems, where the disorder can be described in terms of euclidean random
matrices, is presented. Among others, structural glasses and supercooled
liquids belong to that class of systems. The computation describes their
relevant spectral features in the region of the high frequency sound. The
analytical results are tested with numerical simulations and are found to be in
very good agreement with them. Our results may explain the findings of
inelastic X-ray scattering experiments in various glassy systems.

</DOC>
<DOC>
<DOCNO> 150512 </DOCNO>
TASI lectures on the Holographic Principle


  These TASI lectures review the Holographic principle. The first lecture
describes the puzzle of black hole information loss that led to the idea of
Black Hole Complementarity and subsequently to the Holographic Principle
itself. The second lecture discusses the holographic entropy bound in general
space-times. The final two lectures are devoted to the ADS/CFT duality as a
special case of the principle. The presentation is self contained and
emphasizes the physical principles. Very little technical knowledge of string
theory or supergravity is assumed.

</DOC>
<DOC>
<DOCNO> 69972 </DOCNO>
Next-to-Leading Order Corrections to Heavy Flavour Production in


  A complete next-to-leading order calculation of longitudinally polarized
heavy quark photoproduction is presented. All results of the purturbative
calculation are given in detail. For reactions and energies of interest cross
sections differential in the transverse momentum and rapidity of the heavy
quark, total cross sections and the corresponding asymmetries are given. Errors
in the asymmetries are estimated and the possibility to distinguish between
various scerarios of the polarized gluon distribution is discussed. Our results
are compared with other related publications.

</DOC>
<DOC>
<DOCNO> 120319 </DOCNO>
Wide-Field Thermal Imaging of the Orion Nebula at High Spatial


  We describe multi-wavelength (8--20 micron), diffraction-limited,
mid-infrared images of the OMC-1 cloud core in Orion, covering an approximately
two arcminute area around the Trapezium and BN/KL regions. We have detected
mid-infrared emission at the locations of a subset of the previously identified
proplyds in the Orion Nebula along with two new infrared sources. The Ney-Allen
nebula surrounding the OB star theta 1 Ori d exhibits a ring or toroidal
structure at the longest wavelengths. The BN/KL complex appears as an extended,
butterfly-shaped structure with significant bipolar symmetry which is
bifurcated by a dust lane at the longer wavelengths. The infrared sources IRc3,
4, and 5 give the appearance of a ring-like structure with a possible jet-like
protrusion from its center along a line from IRc2. Derived color temperature
and dust opacity maps suggest that IRc3, 4, and 5 may not be self-luminous
objects.

</DOC>
<DOC>
<DOCNO> 152112 </DOCNO>
Casimir Effect on the Radius Stabilization of the Noncommutative Torus


  We evaluate the one-loop correction to the spectrum of Kaluza-Klein system
for the $\phi^3$ model on $R^{1,d}\times (T_\theta^2)^L$, where $1+d$
dimensions are the ordinary flat Minkowski spacetimes and the extra dimensions
are the L two-dimensional noncommutative tori with noncommutativity $\theta$.
The correction to the Kaluza-Klein mass spectrum is then used to compute the
Casimir energy. The results show that when $L>2$ the Casimir energy due to the
noncommutativity could give repulsive force to stabilize the extra
noncommutative tori in the cases of $d = 4n - 2$, with $n$ a positive integral.

</DOC>
<DOC>
<DOCNO> 150352 </DOCNO>
On Domain-wall/QFT dualities in various dimensions


  We investigate domain-wall/quantum field theory correspondences in various
dimensions. We give particular emphasis to the special case of the quantum
mechanics of 0--branes.

</DOC>
<DOC>
<DOCNO> 100079 </DOCNO>
Variation of moduli of parabolic Higgs bundles


  We study moduli spaces of parabolic Higgs bundles on a curve and their
dependence on the choice of weights. We describe the chamber structure on the
space of weights and show that, when a wall is crossed, the moduli space
undergoes an elementary transformation in the sense of Mukai.

</DOC>
<DOC>
<DOCNO> 122526 </DOCNO>
The evolution of AGN in the Hard X-rays from HELLAS


  We present optical spectroscopic identification of sources identified in the
BeppoSAX MECS fields of the High Energy LLarge Area Survey (HELLAS). In total
62 sources from a sample of 115 brighter than F_{5-10keV}>5x10^{-14} cgs have
been identified. We find a density of 13-21 sources/deg^2 at
F_{5-10keV}>5x10^{-14} cgs, which contribute to 20-30 % of the hard X-ray
background. Evidences are found for type 1 AGN being more absorbed with
increasing redshift or luminosity. The low redshift (z<0.2) ratio of type 2 to
type 1 AGN is 3+/-1.5, in agreement with the unified models for AGN. The
luminosity function of type 1 AGN in the 2-10 keV band is preliminary fitted by
a two-power law function evolving according to a pure luminosity evolution
model: L~(1+z)^{2.2}.

</DOC>
<DOC>
<DOCNO> 13767 </DOCNO>
Footprints in Sand: The Response of a Granular Material to Local


  We experimentally determine ensemble-averaged responses of granular packings
to point forces, and we compare these results to recent models for force
propagation in a granular material. We used 2D granular arrays consisting of
photoelastic particles: either disks or pentagons, thus spanning the range from
ordered to disordered packings. A key finding is that spatial ordering of the
particles is a key factor in the force response. Ordered packings have a
propagative component that does not occur in disordered packings.

</DOC>
<DOC>
<DOCNO> 69603 </DOCNO>
Small x behaviour of parton distributions


  We investigate the Q^2 evolution of parton distributions at small x values,
recently obtained in the case of soft initial conditions. The results are in
excellent agreement with deep inelastic scattering experimental data from HERA.

</DOC>
<DOC>
<DOCNO> 13532 </DOCNO>
Evaluating the critical current magnitude and distribution width of


  In this contribution we present a simple and effective procedure to determine
the average critical current of a tridimensional disordered Josephson junction
array (3D-DJJA). Using a contactless configuration we evaluate the average
critical current and the typical width of the distribution through the analysis
of the isothermal susceptibility response to the excitation field amplitude,
chiAC(h). A 3D-DJJA fabricated from granular Nb is used to illustrate the
method.

</DOC>
<DOC>
<DOCNO> 71914 </DOCNO>
Aspects of parity, CP, and time reversal violation in hot QCD


  We discuss various aspects of parity, CP, and time reversal invariances in
QCD. In particular, we focus attention on the previously proposed possibility
that these experimentally established symmetries of strong interactions may be
broken at finite temperature and/or density. This would have dramatic
signatures in relativistic heavy ion collisions; we describe some of the most
promising signals.

</DOC>
<DOC>
<DOCNO> 102898 </DOCNO>
Discriminants and Functional Equations for Polynomials Orthogonal on the


  We derive raising and lowering operators for orthogonal polynomials on the
unit circle and find second order differential and $q$-difference equations for
these polynomials. A general functional equation is found which allows one to
relate the zeros of the orthogonal polynomials to the stationary values of an
explicit quasi-energy and implies recurrences on the orthogonal polynomial
coefficients. We also evaluate the discriminants and quantized discriminants of
polynomials orthogonal on the unit circle.

</DOC>
<DOC>
<DOCNO> 101824 </DOCNO>
Explicit parallelizations on products of spheres


  The aim of this paper is to write an explicit orthonormal parallelization for
all parallelizable products of spheres, using an explicit isomorphism with a
trivial vector bundle.

</DOC>
<DOC>
<DOCNO> 70759 </DOCNO>
Another Alternative to Compactification: Noncommutative Geometry and


  We observe that the main feature of the Randall-Sundrum model, used to solve
the hierarchy problem, is already present in a class of Yang-Mills plus gravity
theories inspired by noncommutative geometry. Strikingly the same expression
for the Higgs potential is found in two models which have no apparent
connection. Some speculations concerning the possible relationships are given.

</DOC>
<DOC>
<DOCNO> 10592 </DOCNO>
Dynamic Fano Resonance of Quasienergy Excitons in Superlattices


  The dynamic Fano resonance (DFR) between discrete quasienergy excitons and
sidebands of their ionization continua is predicted and investigated in dc- and
ac-driven semiconductor superlattices. This DFR, well controlled by the ac
field, delocalizes the excitons and opens an intrinsic decay channel in
nonlinear four-wave mixing signals.

</DOC>
<DOC>
<DOCNO> 70721 </DOCNO>
Do precision electroweak constraints guarantee $e^+e^-$ collider


  We consider a CP-conserving two-Higgs-doublet type II model with a light
scalar or pseudoscalar neutral Higgs boson ($\h=\hl$ or $\h=\ha$) that has no
$ZZ/WW$ coupling and, thus, cannot be detected in $\epem\to Z\h$
(Higgs-strahlung) or $\nu\anti\nu \h$ (via $WW$ fusion). Despite sum rules
which ensure that the light $\h$ must have significant $t\anti t$ or $b\anti b$
coupling, for a wedge of moderate $\tanb$, that becomes increasingly large as
$\mh$ increases, the $\h$ can also escape discovery in both $b\anti b \h$ and
$t\anti t \h$ production at a $\rts=500-800\gev$ $\epem$ collider (for expected
luminosities). If the other Higgs bosons happen to be too heavy to be produced,
then no Higgs boson would be detected. We demonstrate that, despite such high
masses for the other Higgs bosons, only the low-$\tanb$ portion of the
no-discovery wedges in $[\mh,\tanb]$ parameter space can be excluded due to
failure to fit precision electroweak observables. In the $\tanb\gsim 1$ regions
of the no-discovery wedges, we find that the 2HDM fit to precision electroweak
observables has small $\Delta\chi^2$ relative to the best minimal one-doublet
SM fit.

</DOC>
<DOC>
<DOCNO> 8630 </DOCNO>
The model of the ideal crystal as a criterion for evaluating of the


  It is necessary for the statistical description of collective effects in
liquids to set that or other approximation between direct and pair correlation
functions which describe a neighboring order. The analytical solution of the
generalized Ornstein-Zernike (OZ) equation was obtained for a system of
particles at T=0. It is shown that in this limit case the neighboring order
disappears and the direct correlation function describes a distant order which
is typical for the ideal crystal. The approximation correctly describing the
limit transition liquid-solid at T=0 will have a physical meaning.

</DOC>
<DOC>
<DOCNO> 9950 </DOCNO>
The stability of a cubic fixed point in three dimensions from the


  The global structure of the renormalization-group flows of a model with
isotropic and cubic interactions is studied using the massive field theory
directly in three dimensions. The four-loop expansions of the $\bt$-functions
are calculated for arbitrary $N$. The critical dimensionality $N_c=2.89 \pm
0.02$ and the stability matrix eigenvalues estimates obtained on the basis of
the generalized Pad$\acute{\rm e}$-Borel-Leroy resummation technique are shown
to be in a good agreement with those found recently by exploiting the five-loop
$\ve$-expansions.

</DOC>
<DOC>
<DOCNO> 8457 </DOCNO>
Cryptographical Properties of Ising Spin Systems


  The relation between Ising spin systems and public-key cryptography is
investigated using methods of statistical physics. The insight gained from the
analysis is used for devising a matrix-based cryptosystem whereby the
ciphertext comprises products of the original message bits; these are selected
by employing two predetermined randomly-constructed sparse matrices. The
ciphertext is decrypted using methods of belief-propagation. The analyzed
properties of the suggested cryptosystem show robustness against various
attacks and competitive performance to modern cyptographical methods.

</DOC>
<DOC>
<DOCNO> 117345 </DOCNO>
HST/WFPC2 observations of the core of KjPn 8


  Narrow-band images of the core of the extraordinary poly-polar planetary
nebula KjPn 8 have been obtained with the WFPC2 camera on board the Hubble
Space Telescope. Spasmodic bipolar ejections, in changing directions have
occurred over thousands of years to create KjPn 8. The central star is finally
revealed in these observations and its compact nebular core is resolved into a
remarkably young, aprox. 500 years old, elliptical ring. The highest speed
bipolar outflows are perpendicular to this central ring which is identified as
the latest event in the creation of this nebula. The formation history of KjPn
8 has involved two distinct planetary nebula-like events, probably originating
froma a binary core evolution with components of similar mass.

</DOC>
<DOC>
<DOCNO> 120958 </DOCNO>
Optical Variability of the T Tauri Star HH30


  We report results of VRI photometric monitoring of the T Tauri star plus disk
system HH30. We find that HH30 is highly variable over timescales of a few days
with Delta V~1.5 mag, Delta I~1.1 mag. Furthermore we find hints of periodicity
with periodograms indicating possible periods of 11.6 and 19.8 days. The VRI
photometry is available through the anonymous ftp service. We model the
variability with Monte Carlo radiation transfer simulations for a spotted star
plus disk system and find that the large variability is best reproduced with a
single hot spot and circumstellar grains that are larger than typical
interstellar grains. The apparent existence of a single hot spot and the need
for larger, more forward throwing grains is consistent with previous modeling
of HST imagery.

</DOC>
<DOC>
<DOCNO> 9790 </DOCNO>
An introduction to bosonization and aome of its applications


  We discuss the technique of bosonization for studying systems of interacting
fermions in one dimension. After briefly reviewing the low-energy properties of
Fermi and Luttinger liquids, we present some of the relations between bosonic
and fermionic operators in one dimension. We use these relations to calculate
the correlation functions and the renormalization group properties of various
operators for a system of spinless fermions. We then apply the methods of
bosonization to study the Heisenberg antiferromagnetic spin 1/2 chain, the
Hubbard model in one dimension, and transport in clean quantum wires and in the
presence of isolated impurities.

</DOC>
<DOC>
<DOCNO> 151027 </DOCNO>
Regulating the $P^+ = 0$ Singularity


  I shall discuss the regulation of the $P^+ = 0$ singularity and give some
examples. Regulating the singularity induces new operators into the theory.
This process seems rather different for the case of ultraviolet singularities
than for the case of infrared singularities.

</DOC>
<DOC>
<DOCNO> 150916 </DOCNO>
Gauge-invariant fields in the temporal gauge, Coulomb-gauge fields, and


  We examine the relation between Coulomb-gauge fields and the gauge-invariant
fields constructed in the temporal gauge for two-color QCD by comparing a
variety of properties, including their equal-time commutation rules and those
of their conjugate chromoelectric fields. We also express the temporal-gauge
Hamiltonian in terms of gauge-invariant fields and show that it can be
interpreted as a sum of the Coulomb-gauge Hamiltonian and another part that is
important for determining the equations of motion of temporal-gauge fields, but
that can never affect the time evolution of ``physical'' state vectors. We also
discuss multiplicities of gauge-invariant temporal-gauge fields that belong to
different topological sectors and that, in previous work, were shown to be
based on the same underlying gauge-dependent temporal-gauge fields. We argue
that these multiplicities of gauge-invariant fields are manifestations of the
Gribov ambiguity. We show that the differential equation that bases the
multiplicities of gauge-invariant fields on their underlying gauge-dependent
temporal-gauge fields has nonlinearities identical to those of the ``Gribov''
equation, which demonstrates the non-uniqueness of Coulomb-gauge fields. These
multiplicities of gauge-invariant fields --- and, hence, Gribov copies ---
appear in the temporal gauge, but only with the imposition of Gauss's law and
the implementation of gauge invariance; they do not arise when the theory is
represented in terms of gauge-dependent fields and Gauss's law is left
unimplemented.

</DOC>
<DOC>
<DOCNO> 122857 </DOCNO>
The Optical-Near-IR Spectrum of the M87 Jet From HST Observations


  We present 1998 HST observations of M87 which yield the first single-epoch
optical and radio-optical spectral index images of the jet at $0.15''$
resolution. We find $<\alpha_{ro} > \approx 0.67$, comparable to previous
measurements, and $<\alpha_o > \approx 0.9$ ($F_\nu \propto \nu^{-\alpha}$),
slightly flatter than previous workers. Reasons for this discrepancy are
discussed. These observations reveal a large variety of spectral slopes. Bright
knots exhibit flatter spectra than interknot regions. The flattest spectra
($\alpha_o \sim 0.5-0.6$; comparable to or flatter than $\alpha_{ro}$) are
found in two inner jet knots (D-East and HST-1) which contain the fastest
superluminal components. In knots A, B and C, $\alpha_o$ and $\alpha_{ro}$ are
essentially anti-correlated. Near the flux maxima of knots HST-1 and F, changes
in $\alpha_{ro}$ lag changes in $\alpha_o$, but in knots D and E, the opposite
relationship is observed. This is further evidence that radio and optical
emissions in the M87 jet come from substantially different physical regions.
The delays observed in the inner jet are consistent with localized particle
acceleration, with $t_{acc} << t_{cool}$ for optically emitting electrons in
knots HST-1 and F, and $t_{acc} \sim t_{cool}$ for optically emitting electrons
in knots D and E. Synchrotron models yield $\nu_B \gsim 10^{16}$ Hz for knots
D, A and B, and somewhat lower values, $\nu_B \sim 10^{15}- 10^{16}$ Hz, in
other regions. If X-ray emissions from knots A, B and D are co-spatial with
optical and radio emission, we can strongly rule out the ``continuous
injection'' model. Because of the short lifetimes of X-ray synchrotron emitting
particles, the X-ray emission likely fills volumes much smaller than the
optical emission regions.

</DOC>
<DOC>
<DOCNO> 11406 </DOCNO>
Quantum Phase Fluctuations Responsible for Pseudogap


  The effect of ordering field phase fluctuations on the normal and
superconducting properties of a simple 2D model with a local four-fermion
attraction is studied. Neglecting the coupling between the spin and charge
degrees of freedom an analytical expression has been obtained for the fermion
spectral function as a single integral over a simple function. From this we
show that, as the temperature increases through the 2D critical temperature and
a nontrivial damping for a phase correlator develops, quantum fluctuations fill
the gap in the quasiparticle spectrum. Simultaneously the quasiparticle peaks
broaden significantly above the critical temperature, resembling the observed
pseudogap behavior in high-T_c superconductors.

</DOC>
<DOC>
<DOCNO> 7797 </DOCNO>
Effect of on- and off-ramps in cellular automata models for traffic flow


  We present results on the modeling of on- and off-ramps in cellular automata
for traffic flow, especially the Nagel-Schreckenberg model. We study two
different types of on-ramps that cause qualitatively the same effects. In a
certain density regime one observes plateau formation in the fundamental
diagram. The plateau value depends on the input-rate of cars at the on-ramp.
The on-ramp acts as a local perturbation that separates the system into two
regimes: A regime of free flow and another one where only jammed states exist.
This phase separation is the reason for the plateau formation and implies a
behaviour analogous to that of stationary defects. This analogy allows to
perform very fast simulations of complex traffic networks with a large number
of on- and off-ramps because one can parametrise on-ramps in an exceedingly
easy way.

</DOC>
<DOC>
<DOCNO> 12962 </DOCNO>
Comparative study of mixed monolayers of a calixarene with a fatty acid


  Many nematic liquid crystals (NLCs) lack a polar headgroup and thus are not
able to form stable monolayers at the air/water (a/w) interface. A way to
obtain monomolecular films of these compounds is to incorporate them into host
monolayers of amphiphilic molecules. We report a comparative investigation of
mixed films of Calix[4]resorcinarene O-octacarboxymethylated (CRO) with the
non-amphiphilic NLC MBBA and with the amphiphilic stearic acid (SA). The
comparative study is useful for a better understanding of the characteristics
of the CRO-MBBA mixed films. Surface-pressure and surface-potential
measurements on the monolayers at a/w interface, as well as ellipsometric and
spectroscopic measurements on transferred Langmuir-Blodgett (LB) films, confirm
that MBBA is additively incorporated into CRO films.

</DOC>
<DOC>
<DOCNO> 119181 </DOCNO>
Physical properties of the pulsating hydrogen-deficient star LSS 3184


  We report new determinations of the radius and mass of the pulsating
helium-rich, hydrogen-deficient star LSS 3184 (BX Cir) using measurements of
radial velocity and angular radius throughout its pulsation cycle. Measurements
of radial velocity, and thus changes in stellar radius, were made using
Anglo-Australian Telescope echelle spectra. Hubble Space Telescope ultraviolet
spectra and ground-based BV photometry were used to find temperatures and
fluxes throughout the pulsation cycle. The temperatures and fluxes were used to
find the angular radius of the star (alpha). The alpha, Delta-alpha and
Delta-radius values thus found were used to calculate the mean stellar radius
<R_star> = 2.31 +/- 0.10 R_sun. If we use the previously determined logg = 3.35
+/- 0.1 for LSS 3184 and our radius estimate, we find its mass to be M_star =
0.42 +/- 0.12 M_sun.

</DOC>
<DOC>
<DOCNO> 122520 </DOCNO>
A universal angular momentum profile for galactic halos


  [Abridged] We study the angular-momentum profiles of a statistical sample of
halos drawn from a high-resolution N-body simulation of the LCDM cosmology. We
find that the cumulative mass distribution of specific angular momentum, j, in
a halo of mass Mv is well fit by a universal function, M(<j) = Mv \mu
j/(j_0+j). This profile is defined by one shape parameter (\mu or j_0) in
addition to the global spin parameter \lambda. It follows a power-law over most
of the mass, and flattens at large j, with the flattening more pronounced for
small values of \mu. Compared to a uniform sphere in solid-body rotation, most
halos have a higher fraction of their mass in the low- and high-j tails of the
distribution. The spatial distribution of angular momentum in halos tends to be
cylindrical and is well-aligned within each halo for ~80% of the halos. We
investigate two ideas for the origin of this profile. The first is based on a
revised version of linear tidal-torque theory combined with extended
Press-Schechter mass accretion, and the second focuses on j transport in minor
mergers. Finally, we briefly explore implications of the M(<j) profile on the
formation of galactic disks assuming that j is conserved during an adiabatic
baryonic infall. The implied gas density profile deviates from an exponential
disk, with a higher density at small radii and a tail extending to large radii.
The steep central density profiles may imply disk scale lengths that are
smaller than observed. This is reminiscent of the "angular-momentum problem"
seen in hydrodynamic simulations, even though we have assumed perfect j
conservation. A possible solution is to associate the central excesses with
bulge components and the outer regions with extended gaseous disks.

</DOC>
<DOC>
<DOCNO> 99751 </DOCNO>
A note on the crystalline subrepresentation functor


  We propose the notion of the {\em crystalline sub-representation functor}
defined on $p$-adic representations of the Galois groups of finite extensions
of $\Qp$, with certain restrictions in the case of integral representations. By
studying its right-derived functors, we find a natural extension of a formula
of Grothendieck expressing the group of connected components of a Neron model
of an abelian variety in terms of Galois cohomology.

</DOC>
<DOC>
<DOCNO> 71756 </DOCNO>
Inhomogeneous Big Bang Nucleosynthesis and the High Baryon Density


  The recent Boomerang and MAXIMA data on the cosmic microwave background
suggest a large value for the baryonic matter density of the universe, omega_b
= 0.03. This density is larger than allowed by standard big bang
nucleosynthesis theory and observations on the abundances of the light
elements. We explore here the possibility of accommodating this high density in
inhomogeneous big bang nucleosynthesis (IBBN). It turns out that in IBBN the
observed D and Y_p values are quite consistent with this high density. However,
IBBN is not able to reduce the 7Li yield by more than about a factor of two.
For IBBN to be the solution, one has to accept that the 7Li plateau in
population II halo stars is depleted from the primordial abundance by at least
a factor of two.

</DOC>
<DOC>
<DOCNO> 100106 </DOCNO>
Quantum matrix algebra for the SU(n) WZNW model


  The zero modes of the chiral SU(n) WZNW model give rise to an intertwining
quantum matrix algebra A generated by an n x n matrix a=(a^i_\alpha) (with
noncommuting entries) and by rational functions of n commuting elements
q^{p_i}. We study a generalization of the Fock space (F) representation of A
for generic q (q not a root of unity) and demonstrate that it gives rise to a
model of the quantum universal enveloping algebra U_q(sl_n), each irreducible
representation entering F with multiplicity 1. For an integer level k the
complex parameter q is an even root of unity, q^h=-1 (h=k+n) and the algebra A
has an ideal I_h such that the factor algebra A_h = A/I_h is finite
dimensional.

</DOC>
<DOC>
<DOCNO> 118606 </DOCNO>
A 695-Hz quasi-periodic oscillation in the low-mass X-ray binary EXO


  We report the discovery of a 695-Hz quasi-periodic oscillation (QPO) in data
taken with the Rossi X-ray Timing Explorer of the low-mass X-ray binary (LMXB)
EXO 0748-676. This makes EXO 0748-676 the second dipping LMXB, after 4U
1915-05, that shows kHz QPOs. Comparison with other sources suggests that the
QPO corresponds to the lower frequency peak of the kHz QPO pair often observed
in other LMXBs. The QPO was found in the only observation done during an
outburst of the source in early 1996. This observation is also the only one in
which the ~1 Hz QPO recently found in EXO 0748-676 is not present.

</DOC>
<DOC>
<DOCNO> 150990 </DOCNO>
Supersymmetrizing Branes with Bulk in Five-Dimensional Supergravity


  We supersymmetrize a class of moduli dependent potentials living on branes
with the help of additional bulk terms in 5d N=2 supergravity. The space of
Poincare invariant vacuum solutions includes the Randall-Sundrum solution and
the $M$-theoretical solution. After adding gauge sectors to the branes we
discuss breakdown of low energy supersymmetry in this setup and hierarchy of
physical scales. In the limit of large warp factors we find decoupling between
effects stemming from different branes in the compactified theory.

</DOC>
<DOC>
<DOCNO> 71412 </DOCNO>
Flavor and Quark Mass Dependence of QCD Thermodynamics


  We calculate the transition temperature in 2 and 3-flavor QCD using improved
gauge and staggered fermion actions on lattices with temporal extent Nt=4. We
find Tc=173(8)MeV and 154(8)MeV for nf=2 and 3, respectively. In the case of
3-flavor QCD we present evidence that the chiral critical point, i.e. the
second order endpoint of the line of first order chiral phase transitions,
belongs to the universality class of the 3d Ising model.

</DOC>
<DOC>
<DOCNO> 7832 </DOCNO>
The physics of the stripe quantum critical point in the superconducting


  We elaborate on several observable consequences of the Quantum-Critical-Point
scenario. In particular we show that the strong k-dependent scattering of the
quasiparticles with the quasi-critical charge and spin fluctuations reproduces
the main features of the low-energy spectral weights and of the observed Fermi
surfaces. In the underdoped cuprates the attractive k-dependent charge
scattering drives the formation of the pseudogap at the M points below the
crossover temperature T^*. In this context we discuss models for pseudogap
formation with relevant scattering in the particle-particle and particle-hole
channels. The experimental consequences for the pair-fluctuation and for the
pseudogap behavior are investigated.

</DOC>
<DOC>
<DOCNO> 10353 </DOCNO>
Interface fluctuations in disordered systems: Universality and


  We employ a functional renormalization group to study interfaces in the
presence of a pinning potential in $d=4-\epsilon$ dimensions. In contrast to a
previous approach [D.S. Fisher, Phys. Rev. Lett. {\bf 56}, 1964 (1986)] we use
a soft-cutoff scheme. With the method developed here we confirm the value of
the roughness exponent $\zeta \approx 0.2083 \epsilon$ in order $\epsilon$.
Going beyond previous work, we demonstrate that this exponent is universal. In
addition, we analyze the generation of higher cumulants in the disorder
distribution and the role of temperature as a dangerously irrelevant variable.

</DOC>
<DOC>
<DOCNO> 100559 </DOCNO>
Some isomorphisms for the Brauer groups of a Hopf algebra


  Using equivalences of categories we provide isomorphisms between the Brauer
groups of different Hopf algebras. As an example, we show that when k is a
field of characteristic different from 2 the Brauer groups BC(k,H_4,r_t) for
every dual quasitriangular structure r_t on Sweedler's Hopf algebra H_4 are all
isomorphic to the direct sum of (k,+) and the Brauer-Wall group of k. We
provide an isomorphism between the Brauer group of a Hopf algebra H and the
Brauer group of the dual Hopf algebra H^* generalizing a result of Tilborghs.
Finally we relate the Brauer groups of H and of its opposite and co-opposite
Hopf algebras.

</DOC>
<DOC>
<DOCNO> 170131 </DOCNO>
Time Optimal Control in Spin Systems


  In this paper, we study the design of pulse sequences for NMR spectroscopy as
a problem of time optimal control of the unitary propagator. Radio frequency
pulses are used in coherent spectroscopy to implement a unitary transfer of
state. Pulse sequences that accomplish a desired transfer should be as short as
possible in order to minimize the effects of relaxation and to optimize the
sensitivity of the experiments. Here, we give an analytical characterization of
such time optimal pulse sequences applicable to coherence transfer experiments
in multiple-spin systems. We have adopted a general mathematical formulation,
and present many of our results in this setting, mindful of the fact that new
structures in optimal pulse design are constantly arising. Moreover, the
general proofs are no more difficult than the specific problems of current
interest. From a general control theory perspective, the problems we want to
study have the following character. Suppose we are given a controllable right
invariant system on a compact Lie group, what is the minimum time required to
steer the system from some initial point to a specified final point? In NMR
spectroscopy and quantum computing, this translates to, what is the minimum
time required to produce a unitary propagator? We also give an analytical
characterization of maximum achievable transfer in a given time for the two
spin system.

</DOC>
<DOC>
<DOCNO> 102763 </DOCNO>
Intersection cohomology of Drinfeld's compactifications


  Let $X$ be a smooth complete curve, $G$ be a reductive group and $P\subset G$
a parabolic.
  Following Drinfeld, one defines a compactification $\widetilde{\on{Bun}}_P$
of the moduli stack of $P$-bundles on $X$.
  The present paper is concerned with the explicit description of the
Intersection Cohomology sheaf of $\widetilde{\on{Bun}}_P$. The description is
given in terms of the combinatorics of the Langlands dual Lie algebra
$\check{\mathfrak g}$.

</DOC>
<DOC>
<DOCNO> 122432 </DOCNO>
Very Low Mass Stars and Brown Dwarfs of the Young Open Cluster IC2391


  We have identified a large sample of probable low mass members of the young
open cluster IC2391 based on optical (VRIZ) and Infrared (JHK$_s$) photometry.
Our sample includes 50 probable members and 82 possible members, both very low
mass stars and brown dwarfs. We also provide accurate positions for these stars
and brown dwarf candidates derived from red UK Schmidt plates measured using
the microdensitometer SuperCOSMOS. Assuming an age of 53 Myr, we estimate that
we have reached a mass of 0.025 M$_\odot$, if the identified objects are indeed
members of IC2391.

</DOC>
<DOC>
<DOCNO> 68926 </DOCNO>
Dynamical Chiral Symmetry Breaking on the Light Front.II. The


  An investigation of dynamical chiral symmetry breaking on the light front is
made in the Nambu--Jona-Lasinio model with one flavor and N colors. Analysis of
the model suffers from extraordinary complexity due to the existence of a
"fermionic constraint," i.e., a constraint equation for the bad spinor
component. However, to solve this constraint is of special importance. In
classical theory, we can exactly solve it and then explicitly check the
property of ``light-front chiral transformation.'' In quantum theory, we
introduce a bilocal formulation to solve the fermionic constraint by the 1/N
expansion. Systematic 1/N expansion of the fermion bilocal operator is realized
by the boson expansion method. The leading (bilocal) fermionic constraint
becomes a gap equation for a chiral condensate and thus if we choose a
nontrivial solution of the gap equation, we are in the broken phase. As a
result of the nonzero chiral condensate, we find unusual chiral transformation
of fields and nonvanishing of the light-front chiral charge. A leading order
eigenvalue equation for a single bosonic state is equivalent to a leading order
fermion-antifermion bound-state equation. We analytically solve it for scalar
and pseudoscalar mesons and obtain their light-cone wavefunctions and masses.
All of the results are entirely consistent with those of our previous analysis
on the chiral Yukawa model.

</DOC>
<DOC>
<DOCNO> 12705 </DOCNO>
The Coulomb Luttinger liquid


  The effect of long-ranged Coulomb interaction on the low energy properties
(momentum distribution function, density of states, electron spectral function,
and $4k_F$ correlation function) of one-dimensional electron systems is
determined theoretically. Over a wide, physically relevant energy range the
behavior is found to be well described by the conventional, short-ranged
interacting, Luttinger liquid results, \textit{with a scale-dependent effective
exponent}. An accurate empirical formula for the effective exponent is
presented.

</DOC>
<DOC>
<DOCNO> 12080 </DOCNO>
Analysis of current-voltage characteristics of two-dimensional


  It has been suggested [Pierson et al., Phys. Rev. B 60, 1309 (1999); Ammirata
et al., Physica C 313, 225 (1999)] that for 2D superconductors there exists a
phase transition with the dynamic critical exponent z\approx 5.6. We perform
simulations for the 2D RSJ model and compare the results with the experimental
data in Repaci et al. obtained for an ultrathin YBCO sample [Phys. Rev. B 54,
R9674 (1996)]. We then use a different method of analyzing dynamic scaling than
in Pierson et al., and conclude that both the simulations and the experiments
are consistent with a conventional Kosterlitz Thouless (KT) transition in the
thermodynamic limit for which z=2. For finite systems, however, we find both in
simulations and experiments that the change in the current-voltage (IV)
characteristics caused by the finite size shows a scaling property with an
exponent alpha \approx 1/6, seemingly suggesting a vanishing resistance at a
temperature for which z=1/alpha. It is pointed out that the dynamic critical
exponent found in Pierson et al. corresponds to the exponent 1/alpha. It is
emphasized that this scaling property does not represent any true phase
transition since in reality the resistance vanishes only at zero temperature.
Nevertheless, the observed scaling behavior associated with alpha \approx 1/6
appears to be a common and intriguing feature for the finite size caused change
in the IV characteristics around the KT transition.

</DOC>
<DOC>
<DOCNO> 11358 </DOCNO>
Entanglements in a Quiescent and Sheared Polymer Melt


  Molecular dynamics simulations were performed for a polymer melt. In
quiescent states, the inter-chain interaction energy supported by each particle
takes relatively large values persistently for long times if the particle is
close to an entanglement. Thus, if the interaction is averaged over appropriate
time intervals, we can detect active spots on the chains produced by
entanglement constrains. If rapid shearing is applied, these active regions
subsequently become bended in eventual zig-zag shapes of the chains. We also
demonstrate that stress overshoot occurs with onset of disentanglement.

</DOC>
<DOC>
<DOCNO> 116993 </DOCNO>
An Investigation of Optimised Frequency Distributions for Damping


  In the NLC (Next Linear Collider) small misalignments in each of the
individual accelerator structures (or the accelerator cells) will give rise to
wakefields which kick the beam from its electrical axis. This wakefield can
cause BBU (Beam Break Up) or at the very least it will dilute the emittance of
the beam. Several Gaussian detuned structures have been designed and tested [1]
at SLAC and in this paper we explore new distributions with possibly better
damping properties. The progress of the beam through approximately 5,000
structures is monitored in phase space and results on this are presented.
  [1] J.W. Wang et al, TUA03, LINAC2000

</DOC>
<DOC>
<DOCNO> 102234 </DOCNO>
Rational curves on general projective hypersurfaces


  Let $k$ be an integer such that $1\leq k\leq n-5$, and $X_{2n-2-k}\subset
\mathbf P^n$ a general projective hypersurface of degree $d=2n-2-k$. In this
paper we prove that the only $k$-dimensional subvariety $Y$ of $X_{2n-2-k}$
having geometric genus zero is the one covered by the lines. As an immediate
corollary we obtain that, for $n>5$, the general $X_{2n-3}\subset \mathbf P^n$,
contains no rational curves of degree $\delta >1$.

</DOC>
<DOC>
<DOCNO> 69468 </DOCNO>
The light sigma meson


  In the framework of the dispersion relation N/D-approach, we restore the
low-energy pi-pi (IJ^{PC}=00^{++})-wave amplitude sewing it with the previously
obtained K-matrix solution for the region 450-1900 MeV. The restored
N/D-amplitude has a pole on the second sheet of the complex-s plane near the
pi-pi threshold, that is the light sigma meson.

</DOC>
<DOC>
<DOCNO> 7800 </DOCNO>
High field transport in strained Si/GeSi double heterostructure: a


  We report calculations of high electric field transport for the case of a
strained Si/GeSi double heterostructure (DHS) considering transport along the
Si channel and by applying the analytical Fokker-Planck approach (FPA), where
the process is modeled as drift-diffusion in energy space. We limit ourselves
to electronic transport in the conduction band of the strained Si, where an
energy shift between the otherwise degenerate six energy valleys characterizes
the band alingment in the DHS. Intervalley phonon scatterings are considered
while intravalley acoustic phonon scattering is ignored, leading to results
valid for high enough temperatures. Our results are compared to previous
theoretical works where Monte Carlo simulations were applied. A reasonable
agreement between the two approaches is obtained in the high electric field
regime.

</DOC>
<DOC>
<DOCNO> 99997 </DOCNO>
A Short Survey of Noncommutative Geometry


  We give a survey of selected topics in noncommutative geometry, with some
emphasis on those directly related to physics, including our recent work with
Dirk Kreimer on renormalization and the Riemann-Hilbert problem. We discuss at
length two issues. The first is the relevance of the paradigm of geometric
space, based on spectral considerations, which is central in the theory. As a
simple illustration of the spectral formulation of geometry in the ordinary
commutative case, we give a polynomial equation for geometries on the four
dimensional sphere with fixed volume. The equation involves an idempotent e,
playing the role of the instanton, and the Dirac operator D. It expresses the
gamma five matrix as the pairing between the operator theoretic chern
characters of e and D. It is of degree five in the idempotent and four in the
Dirac operator which only appears through its commutant with the idempotent. It
determines both the sphere and all its metrics with fixed volume form.
  We also show using the noncommutative analogue of the Polyakov action, how to
obtain the noncommutative metric (in spectral form) on the noncommutative tori
from the formal naive metric. We conclude on some questions related to string
theory.

</DOC>
<DOC>
<DOCNO> 84972 </DOCNO>
The Geometric Gravitational Internal Problem


  In a geometric unified theory there is an energy momentum equation, apart
from the field equations and equations of motion. The general relativity
Einstein equation with cosmological constant follows from this energy momentum
equation for empty space. For non empty space we obtain a generalized Einstein
equation, relating the Einstein tensor to a geometric stress energy tensor. The
matching exterior solution is in agreement with the standard relativity tests.
Furthermore, there is a Newtonian limit where we obtain Poisson's equation.

</DOC>
<DOC>
<DOCNO> 118361 </DOCNO>
HST/NICMOS Imaging of the Planetary Nebula Hubble 12


  Images of Hubble 12 were obtained with the HST/NICMOS instrument in the
F110W, F164N, and F166N filters of NIC1, and the F160W, F187N, F190N, F212N,
F215N filters of NIC2. The images show the structure of the inner ``torus'' and
lobes much clearer than previous ground-based images. In particular, the [Fe
II] lobes are clearly resolved and shown to be distinct from the molecular
hydrogen emission structures. Apparent changes in the inner ionized and neutral
bipolar shell implies periodic mass loss or changes in stellar wind shape or
direction. The molecular hydrogen in the ``eye'' is radiatively excited and
shows a complex morphology that suggests that several mass ejection events are
responsible for producing this structure. The position angle of the molecular
hydrogen and [Fe II] lobes differ, indicating a possible precession of the
ejection axis.

</DOC>
<DOC>
<DOCNO> 39673 </DOCNO>
Anomalous f_1 exchange in vector meson photoproduction asymmetries


  We perform an analysis of the elastic production of vector mesons with
polarized photon beams at high energy in order to investigate the validity of a
recently proposed dynamical mechanism based on the dominance of the f_1
trajectory at large momentum transfer. The density matrix characterizing the
angular distributions of the vector meson decays is calculated within an
exchange model which includes the Pomeron and the f_1. The asymmetries of these
decays turn out to be very useful to disentangle the role of these exchanges
since their effect depends crucially on their quantum numbers which are
different. The observables analyzed are accessible with present experimental
facilities.

</DOC>
<DOC>
<DOCNO> 71184 </DOCNO>
Diluting Gravity with Compact Hyperboloids


  I give a brief informal introduction to the idea and tests of large extra
dimensions, focusing on the case in which the space-time manifold has a direct
product structure. I then describe some attractive implementations in which the
internal space comprises a compact hyperbolic manifold. This construction
yields an exponential hierarchy between the usual Planck scale and the true
fundamental scale of physics by tuning only ${\cal O}(1)$ coefficients, since
the linear size of the internal space remains small. In addition, this allows
an early universe cosmology with normal evolution up to substantial
temperatures, and completely evades astrophysical constraints.

</DOC>
<DOC>
<DOCNO> 68145 </DOCNO>
Relic abundance of dark matter particles: new formulation and new result


  A new theoretical framework for computation of the relic abundance of cold
dark matter particles such as LSP is presented and some generic features of new
results are discussed. The most important is a generalization of the Boltzmann
equation to include off-shell effects and its thermal average over cosmic
medium. It is shown that at very low temperatures, much below the mass of
annihilating particles, equilibrium abundance is suppressed only by powers of
temperature instead of the exponential Boltzmann factor. This change gives a
larger relic abundance when heavy particles freeze out at these low
temperatures.

</DOC>
<DOC>
<DOCNO> 123320 </DOCNO>
Bulk Motion Comptonization - a sure sign of Black Holes


  Bulk motion Comptonization utilizes properties of both matter and radiation
close to the horizon of a black hole. Computation with these considerations
produce hard tails of energy spectral slope $\sim 1.5-1.7$. These are the most
direct evidence of the horizon of a black hole. We argue that even in presence
of winds and outflows this property is not likely to change as winds are
negligible in soft states.

</DOC>
<DOC>
<DOCNO> 120431 </DOCNO>
Are there real orthogonal polarization modes in pulsar radio emission?


  The Orthogonal Polarization Modes (OPM) have been reported observationally
and accepted widely by pulsar researchers. However, no acceptable theory can
show the origin of the OPM, which becomes a mystery in pulsar research field.
Here a possible way to solve this mystery is presented. We ask a question: Does
there exist any real so-called OPM in pulsar radiation? It is proposed in this
paper that the `observed OPM' in individual pulses could be the results of
depolarization of pulsar radiation and the observational uncertainties
originated from polarimeter in observation. A possible way to check this idea
is suggested. If the idea is verified, the pulsar research would be influenced
significantly in theory and in observation.

</DOC>
<DOC>
<DOCNO> 40377 </DOCNO>
Recent results from SND detector at VEPP-2M


  The current status of experiments with SND detector at VEPP-2M $e^+e^-$
collider in the energy range $2E_0=0.4-1.4$ GeV is given. The new results of
analysis of $\phi$ decay into $\pi^0\pi^0\gamma$, $\eta\pi^0\gamma$ are based
on the full SND statistics corresponding 20 million of $\phi$ decay. New
measurement of $\omega\to\pi^0\pi^0\gamma$ decay and a first observation of
$\rho\to\pi^0\pi^0\gamma$ are presented. The accuracy of many other rare decays
of light vector mesons was improved. In the energy range $2E_0=1.0\div1.4$ GeV
the cross sections of the processes $e^+e^-\to\omega\pi^0$ and
$e^+e^-\to\pi^+\pi^-\pi^0$ were measured. The results of the fitting of data
are discussed.

</DOC>
<DOC>
<DOCNO> 121820 </DOCNO>
Neutron Star Structure and the Neutron Radius of 208Pb


  We study relationships between the neutron-rich skin of a heavy nucleus and
the properties of neutron-star crusts. Relativistic effective field theories
with a thicker neutron skin in $^{208}$Pb have a larger electron fraction and a
lower liquid-to-solid transition density for neutron-rich matter. These
properties are determined by the density dependence of the symmetry energy
which we vary by adding nonlinear couplings between isoscalar and isovector
mesons. An accurate measurement of the neutron radius in $^{208}$Pb---via
parity violating electron scattering---may have important implications for the
structure of neutron stars.

</DOC>
<DOC>
<DOCNO> 170430 </DOCNO>
Classical wave-optics analogy of quantum information processing


  An analogous model system for quantum information processing is discussed,
based on classical wave optics. The model system is applied to three examples
that involve three qubits: ({\em i}) three-particle Greenberger-Horne-Zeilinger
entanglement, ({\em ii}) quantum teleportation, and ({\em iii}) a simple
quantum error correction network. It is found that the model system can
successfully simulate most features of entanglement, but fails to simulate
quantum nonlocality. Investigations of how far the classical simulation can be
pushed show that {\em quantum nonlocality} is the essential ingredient of a
quantum computer, even more so than entanglement. The well known problem of
exponential resources required for a classical simulation of a quantum
computer, is also linked to the nonlocal nature of entanglement, rather than to
the nonfactorizability of the state vector.

</DOC>
<DOC>
<DOCNO> 8986 </DOCNO>
Coulomb Blockade in the Fractional Quantum Hall Effect Regime


  We use chiral Luttinger liquid theory to study transport through a quantum
dot in the fractional quantum Hall effect regime and find rich non-Fermi-liquid
tunneling characteristics. In particular, we predict a remarkable
Coulomb-blockade-type energy gap that is quantized in units of the
noninteracting level spacing, new power-law tunneling exponents for voltages
beyond threshold, and a line shape as a function of gate voltage that is
dramatically different than that for a Fermi liquid. We propose experiments to
use these unique spectral properties as a new probe of the fractional quantum
Hall effect.

</DOC>
<DOC>
<DOCNO> 39924 </DOCNO>
Photonic events with missing energy in e+e- collisions at sqrt(s)=189


  Photonic events with large missing energy have been observed in e+e-
collisions at a centre-of-mass energy of 189GeV using the OPAL detector at LEP.
Results are presented for event topologies consistent with a single photon or
with an acoplanar photon pair. Cross-section measurements are performed within
the kinematic acceptance of each selection, and the number of light neutrino
species is measured. Cross-section results are compared with the expectations
from the Standard Model process e+e- to nu nubar + photon(s). No evidence is
observed for new physics contributions to these final states. Upper limits are
derived on sigma(e+e- to XY).BR(X to Y gamma) and sigma(e+e- to XX).BR**2(X to
Y gamma) for the case of stable and invisible Y. These limits apply to single
and pair production of excited neutrinos (X=nu*, Y = nu), to neutralino
production (X=neutralino_2, Y=neutralino_1) and to supersymmetric models in
which X = neutralino_1 and Y = light gravitino. The case of macroscopic decay
lengths of particle X is considered for e+e- to XX, X to Y gamma, when M_Y is
of order zero. The single-photon results are also used to place upper limits on
superlight gravitino pair production as well as graviton-photon production in
the context of theories with additional space dimensions.

</DOC>
<DOC>
<DOCNO> 80970 </DOCNO>
Supersymmetry on Lattice Using Ginsparg-Wilson Relation


  The Ginsparg-Wilson(G-W) relation for chiral symmetry is extended for a
supersymmetrical(SUSY) case on a lattice.
 It is possible to define exact lattice supersymmetry which are devided into
two different cases according to using difference operators.
 $U(1)_R$ symmetry on the lattice is also realized as one of exact symmetries.
For an application, the extended G-W relation is given for a two-dimensional
model with chiral multiplets.

</DOC>
<DOC>
<DOCNO> 40573 </DOCNO>
Production Properties of the Orbitally Excited Mesons f_0(980),


  DELPHI results are presented on the inclusive production of the neutral
mesons rho^0, f_0(980), f_2(1270), K^*0_2(1430) and f'_2(1525) in hadronic Z^0
decays. They are based on about 2 million multihadronic events collected in
1994 and 1995, using the particle identification capabilities of the DELPHI
Ring Imaging Cherenkov detectors and measured ionization losses in the Time
Projection Chamber. The total production rates per hadronic Z^0 decay have been
determined to be: 1.19 +/- 0.10 for rho^0; 0.164 +/- 0.021 for f_0(980); 0.214
+/- 0.038 for f_2(1270); 0.073 +/- 0.023 for K^*0_2(1430); and 0.012 +/- 0.006
for f'_2(1525). The total production rates for all mesons and differential
cross-sections for the rho^0, f_0(980) and f_2(1270) are compared with the
results of other LEP experiments and with models.

</DOC>
<DOC>
<DOCNO> 118093 </DOCNO>
Ultra High Energy Cosmic Rays: The theoretical challenge


  The origin of the highest-energy cosmic rays remains a mystery. The lack of a
high energy cutoff in the cosmic ray spectrum together with an apparently
isotropic distribution of arrival directions have strongly constrained most
models proposed for the generation of these particles. An overview of the
present state of theoretical proposals is presented. Astrophysical accelerators
as well as top-down scenarios are reviewed along with their most general
signatures. The origin and nature of these ultra-high energy particles will be
tested by future observations and may indicate as well as constrain physics
beyond the standard model of particle physics.

</DOC>
<DOC>
<DOCNO> 84900 </DOCNO>
Subsystem Entropy Exceeding Bekenstein's Bound


  If Bekenstein's conjectured bound on the microcanonical entropy, S < 2 pi E
R, is applied to a closed subsystem of maximal linear size R and excitation
energy up through E, it can be violated by an arbitrarily large factor by a
scalar field having a symmetric potential allowing domain walls, and by the
electromagnetic field modes in a coaxial cable.

</DOC>
<DOC>
<DOCNO> 68055 </DOCNO>
Leptogenesis with "Fuzzy Mass Shell" for Majorana Neutrinos


  We study the mixing of elementary and composite particles. In quantum field
theory the mixing of composite particles originates in the couplings of the
constituent quarks and for neutrinos in self-energy diagrams. In the event that
the incoming and outgoing neutrinos have different masses, the self-energy
diagrams vanish because energy is not conserved but the finite decaying widths
make the mixing possible. We can consider the neutrinos to be "fuzzy" states on
their mass shell and the mixing is understood as the overlap of two
wavefunctions. These considerations restrict the mass difference to be
approximately equal to or smaller than the largest of the two widths: abs(M_i -
M_j) lessorequal max(Gamma_i, Gamma_j).

</DOC>
<DOC>
<DOCNO> 83437 </DOCNO>
On the relationship between fuzzy logic and four-valued relevance logic


  In fuzzy propositional logic, to a proposition a partial truth in [0,1] is
assigned. It is well known that under certain circumstances, fuzzy logic
collapses to classical logic. In this paper, we will show that under dual
conditions, fuzzy logic collapses to four-valued (relevance) logic, where
propositions have truth-value true, false, unknown, or contradiction. As a
consequence, fuzzy entailment may be considered as ``in between'' four-valued
(relevance) entailment and classical entailment.

</DOC>
<DOC>
<DOCNO> 178983 </DOCNO>
Two-body effects in coherent eta-meson photoproduction on the deuteron


  Coherent $\eta$-meson photoproduction on the deuteron has been studied, where
the emphasis is on the relative importance of two-body contributions from
hadronic rescattering and electromagnetic meson exchange currents besides the
impulse approximation. For the elementary photoproduction amplitude a coupled
resonance model developed by Bennhold and Tanabe has been used which fits
reasonably well the experimental data. The rescattering effects are treated
within a coupled channel approach considering the intermediate excitation of
the $P_{11}(1440)$, $D_{13}(1520)$, and $S_{11}(1535)$ nucleon resonances. The
hadronic interaction between nucleon and resonances is modeled by one boson
exchange potentials, which we have considered both in the static approximation
as well as fully retarded. The sum of all considered two-body effects results
in an enhancement of the total cross section between 10 in the maximum and 25
percent closer to threshold around 680 MeV if the hadronic interaction is
treated retarded. This enhancement shows up in the differential cross sections
mainly at backward angles. It increases steadily from only a few percent at
$0^\circ$ to more than a factor two at $180^\circ$ for a photon energy of 680
MeV. Two-body effects become also significant in certain polarization
observables. Finally, no discrepancy has been found for the ratio of the
isoscalar amplitude to the proton amplitude between coherent and incoherent
$\eta$-photoproduction on the deuteron due to a nonvanishing complex and energy
dependent phase relation.

</DOC>
<DOC>
<DOCNO> 10195 </DOCNO>
Fluctuating Filaments I: Statistical Mechanics of Helices


  We examine the effects of thermal fluctuations on thin elastic filaments with
non-circular cross-section and arbitrary spontaneous curvature and torsion.
Analytical expressions for orientational correlation functions and for the
persistence length of helices are derived, and it is found that this length
varies non-monotonically with the strength of thermal fluctuations. In the weak
fluctuation regime, the local helical structure is preserved and the
statistical properties are dominated by long wavelength bending and torsion
modes. As the amplitude of fluctuations is increased, the helix ``melts'' and
all memory of intrinsic helical structure is lost. Spontaneous twist of the
cross--section leads to resonant dependence of the persistence length on the
twist rate.

</DOC>
<DOC>
<DOCNO> 119878 </DOCNO>
High-Resolution Spectroscopy from 3050 to 10000 A of the HDF-S QSO


  We report on high-resolution observations ($\Re \simeq 45000$) of the Hubble
Deep Field South QSO J2233-606 obtained with the VLT UV-Visual Echelle
Spectrograph (UVES). We present spectral data for the wavelength region $3050 <
\lambda < 10000$ \AA. The $S/N$ ratio of the final spectrum is about 50 per
resolution element at 4000 \AA, 90 at 5000 \AA, 80 at 6000 \AA, 40 at 8000 \AA.
Redshifts, column densities and Doppler widths of the absorption features have
been determined with Voigt-profile fitting. A total of 621 lines have been
measured. In particular 270 Ly-alpha lines, 41 Ly-beta and 24 systems
containing metal lines have been identified. Together with other data in the
literature, the present spectrum confirms that the evolution of the number
density of Ly-alpha lines with $\log N($\huno$) > 14$ has an upturn at $z \sim
1.4-1.6$.

</DOC>
<DOC>
<DOCNO> 118537 </DOCNO>
The Sombrero Galaxy III. Ionised gas and dust in the central 200 pc: a


  We present the results of new 3D TIGER spectroscopic observations and
archived HST/WFPC2 and NICMOS images of the central region of M 104. The
[NII]+Ha images reveal the presence of a nuclear spiral structure, and the
gaseous kinematics in the central arcsecond shows evidence for kinematical
decoupling of the central peak. A straight nuclear dust lane, with a weak
symmetric counterpart, is seen in the V-I and V-H colour maps. These results
hint for the presence of a strong nuclear bar, that would be located inside the
inner Linblad resonance of the large-scale bar discussed by Emsellem (1995).

</DOC>
<DOC>
<DOCNO> 8125 </DOCNO>
Fractal index, central charge and fractons


  We introduce the notion of fractal index associated with the universal class
$h$ of particles or quasiparticles, termed fractons, which obey specific
fractal statistics. A connection between fractons and conformal field
theory(CFT)-quasiparticles is established taking into account the central
charge $c[\nu]$ and the particle-hole duality
$\nu\longleftrightarrow\frac{1}{\nu}$, for integer-value $\nu$ of the
statistical parameter. In this way, we derive the Fermi velocity in terms of
the central charge as $v\sim\frac{c[\nu]}{\nu+1}$. The Hausdorff dimension $h$
which labelled the universal classes of particles and the conformal anomaly are
therefore related. Following another route, we also established a connection
between Rogers dilogarithm function, Farey series of rational numbers and the
Hausdorff dimension.

</DOC>
<DOC>
<DOCNO> 101830 </DOCNO>
The Rost invariant has trivial kernel for quasi-split groups of low rank


  For G an almost simple simply connected algebraic group defined over a field
F, Rost has shown that there exists a canonical map R_G: H^1(F, G) --> H^3(F,
Q/Z(2)). This includes the Arason invariant for quadratic forms and Rost's mod
3 invariant for Albert algebras as special cases. We show that R_G has trivial
kernel if G is quasi-split of type E_6 or E_7. A case-by-case analysis shows
that it has trivial kernel whenever G is quasi-split of low rank.

</DOC>
<DOC>
<DOCNO> 151411 </DOCNO>
Regularization of 2d supersymmetric Yang-Mills theory via non


  The non commutative geometry is a possible framework to regularize Quantum
Field Theory in a nonperturbative way. This idea is an extension of the lattice
approximation by non commutativity that allows to preserve symmetries. The
supersymmetric version is also studied and more precisely in the case of the
Schwinger model on supersphere [14]. This paper is a generalization of this
latter work to more general gauge groups.

</DOC>
<DOC>
<DOCNO> 83245 </DOCNO>
Correlation over Decomposed Signals: A Non-Linear Approach to Fast and


  A novel non-linear approach to fast and effective comparison of sequences is
presented, compared to the traditional cross-correlation operator, and
illustrated with respect to DNA sequences.

</DOC>
<DOC>
<DOCNO> 117287 </DOCNO>
100 Years of Quanta: Complex-Dynamical Origin of Planck's Constant and


  On 14 December 1900 Max Planck first formulated the idea of energy quanta
related to a new universal constant, now known as Planck's constant. Despite
the following progress of the thus initiated 'quantum mechanics', the physical
origin of both quantization and universality of Planck's constant remains
mysterious, as well as other 'peculiar' properties of quantum dynamics. In this
paper we review a recent causal extension of quantum mechanics consistently
explaining all its 'mysteries' by the irreducibly complex, 'dynamically
multivalued' behaviour of the underlying system of two interacting
'protofields' (quant-ph/9902015, quant-ph/9902016). The theory contains no
imposed postulates or entities except one, unavoidable, assumption about the
physical nature of the protofields. All the observed entities and their
properties, starting from physically real space, time, and elementary
particles, are consistently derived, in exact correspondence with their
emergence in the real, irreducibly complex, system dynamics. The latter also
provides natural (dynamic) unification of the causally extended versions of
quantum mechanics, relativity, and field theory, including unification and
causal understanding of the four fundamental forces. Realism and wholeness of
the obtained world picture are in agreement with the 'absolute reality' quest
of Max Planck and confirm his famous 'doubts' in the conventional scheme of
quantum mechanics (cf. quant-ph/9911107, quant-ph/0101129). We describe various
applications of the obtained results providing successful solution to many
fundamental and practical problems (e. g. gr-qc/9906077) dangerously stagnating
within conventional approaches.

</DOC>
<DOC>
<DOCNO> 117651 </DOCNO>
GRB Spectral Hardness and Afterglow Properties


  A possible relationship between the presence of a radio afterglow and
gamma-ray burst spectral hardness is discussed. The correlation is marginally
significant; the spectral hardness of the bursts with radio afterglows
apparently results from a combination of the break energy Ebreak and the
high-energy spectral index beta. If valid, this relationship would indicate
that the afterglow does carry information pertaining to the GRB central engine.

</DOC>
<DOC>
<DOCNO> 118070 </DOCNO>
The Future of Radio Astronomy: Options for Dealing with Human Generated


  Radio astronomy provides a unique window on the universe, allowing us to
study: non-thermal processes (galactic nuclei, quasars, pulsars) at the highest
angular resolution using VLBI, with low opacity. It is the most interesting
wave band for SETI searches. To date it has yielded 3 Nobel prizes (microwave
background, pulsars, gravitational radiation). There are both exciting
possibilities and substantial challenges for radio astronomy to remain at the
cutting edge over the next 3 decades. New instruments like ALMA and the SKA
will open up new science if the challenge of dealing human generated
interference can be met. We summarise some of the issues and technological
developments that will be essential to the future success of radio astronomy.

</DOC>
<DOC>
<DOCNO> 119121 </DOCNO>
Failed Oort Clouds and Planetary Migration


  Planet formation is accompanied by the formation of comet clouds. In systems
where planets migrate on rapid timescales, the diffusive evolution of comet
orbits may stall, resulting in a comet cloud intermediate between a flattened
Kuiper Belt and a spherical Oort cloud. These `failed Oort clouds' may provide
a `smoking gun', indicating that planetary migration has taken place. If some
fraction of the scattered component consists of planetary embryos, it may be
possible to observe transits of such bodies even when the planetary system is
not edge-on to the line of sight.

</DOC>
<DOC>
<DOCNO> 120924 </DOCNO>
Using Perturbative Least Action to Reconstruct Redshift Space


  In this paper, we present a redshift space reconstruction scheme which is
analogous to and extends the Perturbative Least Action (PLA) method described
by Goldberg & Spergel (2000). We first show that this scheme is effective in
reconstructing even nonlinear observations. We then suggest that by varying the
cosmology to minimize the quadrupole moment of a reconstructed density field,
it may be possible to lower the errorbars on the redshift distortion parameter,
$\beta$ as well as to break the degeneracy between the linear bias parameter,
$b$, and $\Omega_M$. Finally, we discuss how PLA might be applied to realistic
redshift surveys.

</DOC>
<DOC>
<DOCNO> 99763 </DOCNO>
Classification of Subsystems for Local Nets with Trivial Superselection


  Let F be a local net of von Neumann algebras in four spacetime dimensions
satisfying certain natural structural assumptions. We prove that if F has
trivial superselection structure then every covariant, Haag-dual subsystem B is
the fixed point net under a compact group action on one component in a suitable
tensor product decomposition of F. Then we discuss some application of our
result, including free field models and certain theories with at most countably
many sectors.

</DOC>
<DOC>
<DOCNO> 119748 </DOCNO>
Generalised inflation with a gravitational wave background


  We propose a Lambda-inflation model which explains a significant part of the
COBE signal by primordial cosmic gravitational waves. The primordial density
perturbations fulfill both the constraints of large-scale microwave background
and galaxy cluster normalization. The model is tested against the galaxy
cluster power spectrum and the high-multipole angular CMB anisotropy.

</DOC>
<DOC>
<DOCNO> 80777 </DOCNO>
Operator Product Expansion on the Lattice: a Numerical Test in the


  We consider the short-distance behaviour of the product of the Noether O(N)
currents in the lattice nonlinear sigma-model. We compare the numerical results
with the predictions of the operator product expansion, using one-loop
perturbative renormalization-group improved Wilson coefficients. We find that,
even on quite small lattices (m a \approx 1/6), the perturbative operator
product expansion describes that data with an error of 5-10% in a large window
2a \ltapprox x \ltapprox m^{-1}. We present a detailed discussion of the
possible systematic errors.

</DOC>
<DOC>
<DOCNO> 9772 </DOCNO>
Statistical Asynchronous Regression: Determining the Relationship


  We introduce the Statistical Asynchronous Regression (SAR) method: a
technique for determining a relationship between two time varying quantities
without simultaneous measurements of both quantities. We require that there is
a time invariant, monotonic function Y = u(X) relating the two quantities, Y
and X. In order to determine u(X), we only need to know the statistical
distributions of X and Y. We show that u(X) is the change of variables that
converts the distribution of X into the distribution of Y, while conserving
probability. We describe an algorithm for implementing this method and apply it
to several example distributions. We also demonstrate how the method can
separate spatial and temporal variations from a time series of energetic
electron flux measurements made by a spacecraft in geosynchronous orbit. We
expect this method will be useful to the general problem of spacecraft
instrument calibration. We also suggest some applications of the SAR method
outside of space physics.

</DOC>
<DOC>
<DOCNO> 84867 </DOCNO>
R-modes in Neutron Stars with Crusts: Turbulent Saturation, Spin-down,


  Rossby waves (r-modes) have been suggested as a means to regulate the spin
periods of young or accreting neutron stars, and also to produce observable
gravitational wave radiation. R-modes involve primarily transverse,
incompressive motions of the star's fluid core. However, neutron stars gain
crusts early in their lives: therefore, r-modes also imply shear in the fluid
beneath the crust. We examine the criterion for this shear layer to become
turbulent, and derive the rate of dissipation in the turbulent regime. Unlike
dissipation from a viscous boundary layer, turbulent energy loss is nonlinear
in mode energy and can therefore cause the mode to saturate at amplitudes
typically much less than unity. This energy loss also reappears as heat below
the crust. We study the possibility of crust melting as well as its
implications for the spin evolution of low-mass X-ray binaries. Lastly, we
identify some universal features of the spin evolution that may have
observational consequences.

</DOC>
<DOC>
<DOCNO> 118546 </DOCNO>
The DENIS Point Source Catalogue towards the Magellanic Clouds


  We have compiled the near infrared Point Source Catalogue (PSC) towards the
Magellanic Clouds (MCs) extracted from the data obtained with the Deep Near
Infrared Survey of the Southern Sky - DENIS (Epchtein et al. 1997). The
catalogue covers an area of of 19.87* 16 square degrees centered on (RA,
DEC)=(5h27m20s, -69o00'00'') for the Large Magellanic Cloud (LMC) and 14.7* 10
square degrees centered on (RA, DEC)=(h02m40s, -73o00'00'' for the Small
Magellanic Cloud (SMC) at the epoch J2000. It contains about 1300000 sources
towards the LMC and 300000 sources towards the SMC each detected in at least 2
of the 3 photometric bands involved in the survey (I, J, Ks). 70% of the
detected sources are true members of the Magellanic Clouds, respectively and
consist mainly of red giants, asymptotic giant branch stars and super-giants.
The observations have all been made with the same instrument and the data have
been calibrated and reduced uniformly. The catalogue provides a homogeneous set
of photometric data.

</DOC>
<DOC>
<DOCNO> 122071 </DOCNO>
The Giant Flare of 1998 August 27 from SGR 1900+14: I. An Interpretive


  The giant flare of 1998 August 27 from SGR 1900+14 was extraordinary in many
ways: it was the most intense flux of gamma rays ever detected from a source
outside our solar system; it was longer than any previously detected burst from
a soft gamma repeater (SGR) in our Galaxy by more than an order of magnitude;
and it showed a remarkable four-peaked, periodic pattern in hard X-rays with
the same rotation period that was found modulating soft X-rays from the star in
quiescence. The event was detected by several gamma-ray experiments in space,
including the Ulysses gamma-ray burst detector and the BeppoSAX Gamma Ray Burst
Monitor. These instruments operate in different energy ranges, and comparisons
of their measurements reveal complex patterns of spectral evolution as the
intensity varies. In this paper, we present a joint analysis of the BeppoSAX
and Ulysses data and discuss some implications of these results for the SGRs.
We also present newly-analyzed Venera/SIGNE and ISEE-3 data on the 1979 March 5
giant flare from an SGR in the Large Magellanic Cloud (SGR 0526-66), and
compare them with the August 27 event. Our results are consistent with the
hypothesis that giant flares are due to catastrophic magnetic instabilities in
highly magnetized neutron stars, or "magnetars".

</DOC>
<DOC>
<DOCNO> 84911 </DOCNO>
On the propagation of jump discontinuities in relativistic cosmology


  A recent dynamical formulation at derivative level $\ptl^{3}g$ for fluid
spacetime geometries $({\cal M}, {\bf g}, {\bf u})$, that employs the concept
of evolution systems in first-order symmetric hyperbolic format, implies the
existence in the Weyl curvature branch of a set of timelike characteristic
3-surfaces associated with propagation speed $|v| = \sfrac{1}{2}$ relative to
fluid-comoving observers. We show it is the physical role of the constraint
equations to prevent realisation of jump discontinuities in the derivatives of
the related initial data so that Weyl curvature modes propagating along these
3-surfaces cannot be activated. In addition we introduce a new, illustrative
first-order symmetric hyperbolic evolution system at derivative level
$\ptl^{2}g$ for baryotropic perfect fluid cosmological models that are
invariant under the transformations of an Abelian $G_{2}$ isometry group.

</DOC>
<DOC>
<DOCNO> 11975 </DOCNO>
Exclusion Statistics in a trapped two-dimensional Bose gas


  We study the statistical mechanics of a two-dimensional gas with a repulsive
delta function interaction, using a mean field approximation. By a direct
counting of states we establish that this model obeys exclusion statistics and
is equivalent to an ideal exclusion statistics gas.

</DOC>
<DOC>
<DOCNO> 102866 </DOCNO>
From local to global deformation quantization of Poisson manifolds


  We give an explicit construction of a deformation quantization of the algebra
of functions on a Poisson manifolds, based on Kontsevich's local formula. The
deformed algebra of functions is realized as the algebra of horizontal sections
of a vector bundle with flat connection.

</DOC>
<DOC>
<DOCNO> 84280 </DOCNO>
Initial data and spherical dust collapse


  By considering families of radial null geodesics, we study the subsets of
initial data that lead to naked singularities and black holes in inhomogeneous
spherical dust collapse. We introduce the notion of central homogeneity for
spherical dust collapse and prove that for the occurrence of naked
singularities, the initial data set must in general be centrally homogeneous.
Even though mathematically this indicates that naked singularities are in
general unstable, we show that centrally inhomogeneous perturbations in the
initial data are not physically reasonable. This provides an example of the
fact that instability in this context deduced with respect to general
perturbations can become stabilised once the class of perturbations are
restricted to be physical.

</DOC>
<DOC>
<DOCNO> 122261 </DOCNO>
The Dying Wind Around HD 56126, A Post-AGB Carbon Star


  We have used the Keck I telescope to resolve at mid-infrared wavelengths the
dust emission from HD 56126 (IRAS 07134+1005), a post-Asymptotic Giant Branch
carbon star with a detached dust shell. The gross morphology of the image can
be explained by a strong wind which started to die about 1500 years ago. If the
star had an effective temperature near 2600 K when it was losing a large amount
of mass, then during the past 1500 years, the average value of dT/dt has been
+2.2 K/yr. With such a time variation of the effective temperture of the star,
the 11.7 micron image can be approximately reproduced if the mass loss rate
varied as T^(-8.26), as proposed in recent models for dust-driven winds. Since
the mass loss rate appears to be very sensitive to the effective temperature of
the star, we speculate that the observed deviations from spherical symmetry of
the dust shell can be explained by plausible variations in the surface
temperature of the mass-losing star caused by rotation and/or magnetic fields.

</DOC>
<DOC>
<DOCNO> 99788 </DOCNO>
Gauge transformations on locally trivial quantum principal fibre bundles


  If P, B, H are the algebras of the total space, the base space, and the
structure group of a locally trivial principal fibre bundle (QPFB), left
(right) gauge transformations are defined as automorphisms of the left (right)
B-module P which are adapted to the coaction of the Hopf algebra H and to the
covering related to the local trivializations. Covariant derivatives on a QPFB
are always transformed into covariant derivatives. This is true for connections
only for special choices of the differential structure on H and/or if one
restricts to algebra automorphisms. There are analogues of the classical
formulas relating local connection forms and their gauge transforms.

</DOC>
<DOC>
<DOCNO> 68881 </DOCNO>
Supersymmetric Electroweak Baryogenesis and CP Violation


  I review the mechanism of electroweak baryogenesis within the framework of a
string motivated supersymmetric extension of the Standard Model with large
flavor-independent CP-violating phases. Possible implications for the Higgs
sector are considered in correlation with the properties of the right-handed
stop. I also comment on the compatibility of supersymmetric electroweak
baryogenesis with various CP-violating observables.

</DOC>
<DOC>
<DOCNO> 169931 </DOCNO>
Three-particle GHZ correlations without nonlocality


  The formalism employing local complex amplitudes that resolved the
Einstein-Podolsky-Rosen puzzle (C. S. Unnikrishnan, quant-ph/0001112) is
applied to the three-particle GHZ correlations. We show that the GHZ quantum
correlations can be reproduced without nonlocality.

</DOC>
<DOC>
<DOCNO> 9919 </DOCNO>
Folding Energetics in Thin-Film Diaphragms


  We perform experiments on thin-film diaphragms to show that the folding
patterns of anisotropically compressed diaphragms are strikingly different from
those of isotropically compressed ones. We then use a simple von Karman model
to relate the overall features of these folding patterns to the underlying
energetics. We show that the differences between the isotropic and anisotropic
cases can be traced back to fundamental changes in the energy structure of the
diaphragms. Finally, we point out that the energy structure of thin-film
diaphragms is similar to that of many other systems in physics and engineering,
into which our study may provide interesting insights.

</DOC>
<DOC>
<DOCNO> 120176 </DOCNO>
Chemical abundances in seven red giants of NGC 2360 and NGC 2447


  Chemical abundances of about fifteen elements from oxygen to europium are
measured in seven red giants of the two open clusters NGC 2360 and NGC 2447.
The effective temperatures of the giants are determined spectroscopically by
taking advantage of their known masses (~2 Mo in NGC 2360 and ~3 Mo in NGC
2447) and bolometric magnitudes.
  The average iron abundances we obtain for the two clusters are [Fe/H]=0.07
for NGC 2360 and [Fe/H]=0.03 for NGC 2447.
  Evolutionary stellar model calculations are performed in the mass range 1-4
Mo in order to analyze the surface Na and O abundances predicted after the
first dredge-up. The sodium abundance shows a well defined correlation with
stellar mass in the 2-3 Mo range. The agreement between our Na abundance
determinations in NGC 2360 and our model predictions at 2 Mo is very good. In
contrast, the overabundance in one of the three stars in NGC 2447 exceeds that
predicted at 3 Mo by ~0.08 dex, which is significant compared to the
observational error bars. The effects of core overshooting, convection
prescription, metallicity and nuclear reaction rates on the Na surface
predictions of our models are investigated.
  An oxygen deficiency relative to iron by 0.2 dex is measured in our stars, in
disagreement with our model predictions. Assuming that the Sun is 0.1-0.3 dex
enriched in oxygen relative to neighbor stars could explain the discrepancy.

</DOC>
<DOC>
<DOCNO> 118111 </DOCNO>
ISO-LWS spectroscopy of Centaurus A: extended star formation


  We present the first full FIR spectrum of Centaurus A (NGC 5128) from 43 -
196.7 um. The data was obtained with the ISO Long Wavelength Spectrometer
(LWS). We conclude that the FIR emission in a 70 arcsec beam centred on the
nucleus is dominated by star formation rather than AGN activity. The flux in
the far-infrared lines is ~ 1 % of the total FIR: the [CII] line flux is ~ 0.4
% FIR and the [OI] line is ~ 0.2 %, with the remainder arising from [OIII],
[NII] and [NIII] lines. These are typical values for starburst galaxies.
  The ratio of the [NIII]/[NII] line intensities from the HII regions in the
dust lane can be modelled as a ~ 6 million year old starburst. This suggests
that the galaxy underwent either a recent merger or a merger which triggered a
series of bursts.
  We estimate that < 5 % of the observed [CII] arises in the cold neutral
medium (CNM) and that ~ 10 % arises in the warm ionized medium (WIM). The main
contributors to the [CII] emission are the PDRs, which are located throughout
the dust lane and in regions beyond where the bulk of the molecular material
lies. On scales of ~ 1 kpc the average physical properties of the PDRs are
modelled with a gas density, n ~ 1000 cm^-3, an incident far-UV field, G ~ 100
times the local Galactic field, and a gas temperature of ~ 250 K.

</DOC>
<DOC>
<DOCNO> 170129 </DOCNO>
Proposal for measurment of harmonic oscillator Berry phase in ion traps


  We propose a scheme for measuring the Berry phase in the vibrational degree
of freedom of a trapped ion. Starting from the ion in a vibrational coherent
state we show how to reverse the sign of the coherent state amplitude by using
a purely geometric phase. This can then be detected through the internal
degrees of freedom of the ion. Our method can be applied to preparation of
Schr\"odinger cat states.

</DOC>
<DOC>
<DOCNO> 68860 </DOCNO>
Strong coupling constant from bottomonium fine structure


  From a fit to the experimental data on the $b\bar{b}$ fine structure, the
two-loop coupling constant is extracted. For the 1P state the fitted value is
$\alpha_s(\mu_1) = 0.33 \pm 0.01(exp)\pm 0.02 (th)$ at the scale $\mu_1 = 1.8
\pm 0.1$ GeV, which corresponds to the QCD constant $\Lambda^{(4)}(2-loop) =
338 \pm 30$ MeV (n_f = 4) and $\alpha_s(M_Z) = 0.119 \pm 0.002. For the 2P
state the value $\alpha_s(\mu_2) = 0.40 \pm 0.02(exp)\pm 0.02(th)$ at the scale
$\mu_2 = 1.02 \pm 0.2$ GeV is extracted, which is significantly larger than in
the previous analysis of Fulcher (1991) and Halzen (1993), but about 30%
smaller than the value given by standard perturbation theory. This value
$\alpha_s(1.0) \approx 0.40$ can be obtained in the framework of the background
perturbation theory, thus demonstrating the freezing of $\alpha_s$. The
relativistic corrections to $\alpha_s$ are found to be about 15%.

</DOC>
<DOC>
<DOCNO> 68221 </DOCNO>
The Structure of the QCD Potential in 2+1 Dimensions


  We calculate the screening and anti-screening contributions to the
inter-quark potential in 2+1 dimensions, which is relevant to the high
temperature limit of QCD. We demonstrate that the relative strength of
screening to anti-screening agrees with the 3+1 dimensional theory to better
than one percent accuracy.

</DOC>
<DOC>
<DOCNO> 122198 </DOCNO>
Future X-ray timing missions


  Thanks to the Rossi X-ray Timing Explorer (RXTE), it is now widely recognized
that fast X-ray timing can be used to probe strong gravity fields around
collapsed objects and constrain the equation of state of dense matter in
neutron stars. We first discuss some of the outstanding issues which could be
solved with an X-ray timing mission building on the great successes of RXTE and
providing an order of magnitude better sensitivity. Then we briefly describe
the 'Experiment for X-ray timing and Relativistic Astrophysics' (EXTRA)
recently proposed to the European Space Agency as a follow-up to RXTE and the
related US mission 'Relativistic Astrophysics Explorer' (RAE).

</DOC>
<DOC>
<DOCNO> 68349 </DOCNO>
Nonlinear gauge interactions - A solution to the "measurement problem"


  We propose that the mechanism responsible for the ``collapse of the wave
function" (or "decoherence" in its broadest meaning) in quantum mechanics is
the nonlinearities already present in the theory via nonabelian gauge
interactions. Unlike all other models of spontaneous collapse, our proposal is,
to the best of our knowledge, the only one which does not introduce any new
elements into the theory. Indeed, unless the gauge interaction nonlinearities
are not used for exactly this purpose, one must then explain why the violation
of the superposition principle which they introduce does not destroy quantum
mechanics. A possible experimental test of the model would be to compare the
coherence lengths for, e.g., electrons and photons in a double-slit experiment.
The electrons should have a finite coherence length, while photons should have
a much longer (in principle infinite) coherence length.

</DOC>
<DOC>
<DOCNO> 178617 </DOCNO>
Dynamic and Quasistatic Trajectories in Quasifission Reactions and


  We show that the quasifission paths predicted by the one-body dissipation
dynamics, in the slowest phase of a binary reaction, follow a quasistatic path,
which represents a sequence of states of thermal equilibrium at a fixed value
of the deformation coordinate. This establishes the use of the statistical
particle-evaporation model in the case of dynamical time-evolving systems. Pre-
and post-scission multiplicities of neutrons and total multiplicities of
protons and alpha particles in fission reactions of 63Cu+92Mo, 60Ni+100Mo,
63Cu+100Mo at 10 MeV/u and 20Ne+144,148,154Sm at 20 MeV/u are reproduced
reasonably well with statistical model calculations performed along dynamic
trajectories whose slow stage (from the most compact configuration up to the
point where the neck starts to develop) lasts some 35x10^{-21} s.

</DOC>
<DOC>
<DOCNO> 169616 </DOCNO>
Decoherence in QED at finite temperature


  We consider a wave packet of a charged particle passing through a cavity
filled with photons at temperature T and investigate its localization and
interference properties. It is shown that the wave packet becomes localized and
the interference disappears with an exponential speed after a sufficiently long
path through the cavity.

</DOC>
<DOC>
<DOCNO> 8361 </DOCNO>
Effect of Magnetic Impurities on Suppression of the Transition


  We calculate the first-order perturbative correction to the transition
temperature $T_c$ in a superconductor with both non-magnetic and magnetic
impurities. We do this by first evaluating the correction to the effective
potential, $\Omega(\Delta)$, and then obtain the first-order correction to the
order parameter, $\Delta$, by finding the minimum of $\Omega(\Delta)$. Setting
$\Delta=0$ finally allows $T_c$ to be evaluated. $T_c$ is now a function of
both the resistance per square, $R_\square$, a measure of the non-magnetic
disorder, and the spin-flip scattering rate, $1/\tau_s$, a measure of the
magnetic disorder. We find that the effective pair-breaking rate per magnetic
impurity is virtually independent of the resistance per square of the film, in
agreement with an experiment of Chervenak and Valles. This conclusion is
supported by both the perturbative calculation, and by a non-perturbative
re-summation technique.

</DOC>
<DOC>
<DOCNO> 118363 </DOCNO>
The shock waves in decaying supersonic turbulence


  We here analyse numerical simulations of supersonic, hypersonic and
magnetohydrodynamic turbulence that is free to decay. Our goals are to
understand the dynamics of the decay and the characteristic properties of the
shock waves produced. This will be useful for interpretation of observations of
both motions in molecular clouds and sources of non-thermal radiation.
  We find that decaying hypersonic turbulence possesses an exponential tail of
fast shocks and an exponential decay in time, i.e. the number of shocks is
proportional to t exp (-ktv) for shock velocity jump v and mean initial
wavenumber k. In contrast to the velocity gradients, the velocity Probability
Distribution Function remains Gaussian with a more complex decay law.
  The energy is dissipated not by fast shocks but by a large number of low Mach
number shocks. The power loss peaks near a low-speed turn-over in an
exponential distribution. An analytical extension of the mapping closure
technique is able to predict the basic decay features. Our analytic description
of the distribution of shock strengths should prove useful for direct modeling
of observable emission. We note that an exponential distribution of shocks such
as we find will, in general, generate very low excitation shock signatures.

</DOC>
<DOC>
<DOCNO> 71474 </DOCNO>
New form of matter at CERN SPS: Quark Matter but not Quark Gluon Plasma


  I argue that a new form of matter is indeed seen in Pb+Pb collisions at CERN
SPS. However, this Quark Matter (QM) is different from the theoretically
predicted Quark Gluon Plasma (QGP) because its effective degrees of freedom
seem to be the massive (dressed) constituent quarks instead of almost massless
quarks and gluons. The equation of state of QM is hard,the time of its
rehadronization is short, while the equation of state of a QGP is soft and the
time of its rehadronization is long. Other similarities and differences are
also summarized.

</DOC>
<DOC>
<DOCNO> 116892 </DOCNO>
RF Control System for the NLC Linacs


  The proposed Next Linear Collider contains a large number of linac RF systems
with new requirements for wideband klystron modulation and accurate RF vector
detection. The system will be capable of automatically phasing each klystron
and compensating for beam loading effects. Accelerator structure alignment is
determined by detection of the beam induced dipole modes with a receiver
similar to that used for measuring the accelerator RF and is incorporated into
the RF system topology. This paper describes the proposed system design, signal
processing techniques and includes preliminary test results.

</DOC>
<DOC>
<DOCNO> 13970 </DOCNO>
The phase-separated states in antiferromagnetic semiconductors with


  The possibility of the slab or stripe phase separation (alternating
ferromagnetic highly- conductive and insulating antiferromagnetic layers) is
proved for isotropic degenerate antiferromagnetic semiconductors. This type of
phase separation competes with the droplet phase separation (ferromagnetic
droplets in the antiferromagnetic host or vice versa). The interaction of
electrons with optical phonons alone cannot cause phase-separated state with
alternating highly-conductive and insulating regions but it stabilizes the
magnetic phase separation. The magnetostriction deformation of the lattice in
the phase-separated state is investigated.

</DOC>
<DOC>
<DOCNO> 68076 </DOCNO>
Dyson-Schwinger Equation Approach to the QCD Deconfinement Transition


  We consider an extension of the finite-temperature Dyson-Schwinger equation
(DSE) approach to heavy mesons and quarkonia and apply it to calculate the
cross section for the J/Psi breakup reaction J/Psi + pi --> D + D. We study the
effects of chiral symmetry restoration in the light quark sector on this
process and obtain a critical enhancement of the reaction rate at the chiral/
deconfinement transition. Implications for the kinetics of charmonium
production in ultrarelativistic heavy-ion collisions are discussed with
particular emphasis on the recently observed anomalous J/Psi suppression as a
possible signal for quark matter formation.

</DOC>
<DOC>
<DOCNO> 85471 </DOCNO>
Hair from the Isolated Horizon Perspective


  The recently introduced Isolated Horizons (IH) formalism has become a
powerful tool for realistic black hole physics. In particular, it generalizes
the zeroth and first laws of black hole mechanics in terms of quasi-local
quantities and serves as a starting point for quantum entropy calculations. In
this note we consider theories which admit hair, and analyze some new results
that the IH provides, when considering solitons and stationary solutions.
Furthermore, the IH formalism allows to state uniqueness conjectures (i.e.
horizon `no-hair conjectures') for the existence of solutions.

</DOC>
<DOC>
<DOCNO> 71753 </DOCNO>
Charmless decays B -> PP, PV, and effects of new strong and electroweak


  Based on the low energy effective Hamiltonian with generalized factorization,
we calculate the new physics contributions to the branching ratios and
CP-violating asymmetries of the two-body charmless hadronic decays $B \to PP,
PV$ from the new strong and electroweak penguin diagrams in the TC2 model. The
top-pion penguins dominate the new physics corrections, and both new gluonic
and electroweak penguins contribute effectively to most decay modes. For
tree-dominated decay modes $B \to \pi \pi, \rho \pi, etc,$ the new physics
corrections are less than 10%. For decays $B \to K^{(*)} \pi$, $K^{(*)} \eta$,
$etc$, the new physics enhancements can be rather large (from $- 70%$ to $\sim
200%$) and are insensitive to the variations of $N_c^{eff}$, $k^2$, $\eta$ and
$m_{\tilde{\pi}}$ within the reasonable ranges. For decays $B^0 \to \phi \pi$,
$\phi \eta^{(')}$, $K^* \bar{K}^0$ and $\rho^+ K^0$, $\delta {\cal B}$ is
strongly $N_c^{eff}-$dependent: varying from -90% to $\sim 1680%$ in the range
of $N_c^{eff}=2-\infty$. The new physics corrections to the CP-violating
asymmetries ${\cal A}_{CP}$ vary greatly for different B decay channels. For
five measured CP asymmetries of $B \to K \pi, K \eta', \omega \pi$ decays,
$\delta {\cal A}_{CP}$ is only about 20% and will be masked by large
theoretical uncertainties. The new physics enhancements to interesting $B \to K
\eta'$ decays are significant in size ($\sim 50%$), insensitive to the
variations of input parameters and hence lead to a plausible interpretation for
the unexpectedly large $B \to K \eta'$ decay rates. The TC2 model predictions
for branching ratios and CP-violating asymmteries of all fifty seven $B \to PP,
PV$ decay modes are consistent with the available data within one or two
standard deviations.

</DOC>
<DOC>
<DOCNO> 117398 </DOCNO>
Supernova Remnants, Pulsars and the Interstellar Medium - Summary of a


  We summarise the proceedings of the SRCfTA workshop on ``Supernova Remnants,
Pulsars and the Interstellar Medium'' that was held at the University of Sydney
on Mar 18 and 19, 1999.

</DOC>
<DOC>
<DOCNO> 71415 </DOCNO>
Quenched and first unquenched lattice HQET determination of the Bs-Meson


  We present recent results for the prediction of the Bs lifetime difference
from lattice Heavy Quark Effective Theory simulations. In order to get a
next-to-leading order result we have calculated the matching between QCD and
HQET and the two-loop anomalous dimensions in the HQET for all the \Delta B=2
operators, in particular for the operators which enter the width difference. We
present results from quenched and, for the first time, from unquenched
simulations. We obtain for the Bs lifetime difference,
(\Delta\Gamma_Bs/\Gamma_Bs)^{(que.)}=(5.1+/- 1.9+/- 1.7)10^(-2) and
(\Delta\Gamma_Bs/\Gamma_Bs)^{(unq.)}=(4.3+/- 2.0+/- 1.9)10^(-2) from the
quenched and unquenched simulations respectively

</DOC>
<DOC>
<DOCNO> 102782 </DOCNO>
Invitation to higher local fields, Part I, section 17: An approach to


  This is an introduction to author's ramification theory of a complete
discrete valuation field with residue field whose p-basis consists of at most
one element. New lower and upper filtrations are defined; cyclic extensions of
degree p may have non-integer ramification breaks. A refinement of the
filtration for two-dimensional local fields which is compatible with the
reciprocity map is discussed.

</DOC>
<DOC>
<DOCNO> 117848 </DOCNO>
Oscillation Waveforms and Amplitudes from Hot Spots on Neutron Stars


  The discovery of high-amplitude brightness oscillations during type I X-ray
bursts from six low-mass X-ray binaries has provided a powerful new tool to
study the properties of matter at supranuclear densities, the effects of strong
gravity, and the propagation of thermonuclear burning. There is substantial
evidence that these brightness oscillations are produced by spin modulation of
one or two localized hot spots confined to the stellar surface. It is therefore
important to calculate the expected light curves produced by such hot spots
under various physical assumptions, so that comparison with the observed light
curves may most sensitively yield information about the underlying physical
quantities. In this paper we make general relativistic calculations of the
light curves and oscillation amplitudes produced by a rotating neutron star
with one or two hot spots as a function of spot size, stellar compactness,
rotational velocity at the stellar surface, spot location, orientation of the
line of sight of the observer, and the angular dependence of the surface
specific intensity. We find that stellar rotation and beaming of the emission
tend to increase the observed oscillation amplitudes whereas greater
compactness and larger spot size tend to decrease them. By applying these
results to 4U 1636--536, we show that this source must have two emitting spots
and place strong constraints on the neutron star's magnetic field geometry. We
also show that the data on the phase lags between photons of different energies
in the persistent pulsations in SAX J1808--58 can be fit well with a model in
which the observed hard leads are due to Doppler beaming.

</DOC>
<DOC>
<DOCNO> 80576 </DOCNO>
Global Anomalies in chiral gauge theories on the lattice


  We discuss the issue of global anomalies in chiral gauge theories on the
lattice. In Luscher's approach, these obstructions make it impossible to define
consistently a fermionic measure for the path integral. We show that an SU(2)
theory has such a global anomaly if the Weyl fermion is in the fundamental
representation. The anomaly in higher representations is also discussed. We
finally show that this obstruction is the lattice analogue of the SU(2) anomaly
first discovered by Witten.

</DOC>
<DOC>
<DOCNO> 121385 </DOCNO>
VLBI Observations of Five Compact Radio Sources


  Five compact radio sources, include 0420-014, 1334-127, 1504-166, 2243-123,
and 2345-167, were observed at 5GHz by European VLBI (Very Long Baseline
Interferometry) Network (EVN) in June, 1996. The primary purpose of this
observation was to confirm their superluminal proper motions. Here, the results
of 1334-127, 1504-166, 2243-123 and 2345-167 are presented.

</DOC>
<DOC>
<DOCNO> 10225 </DOCNO>
Parity Effect in a mesoscopic superconducting ring


  We study a mesoscopic superconducting ring threaded by a magnetic flux when
the single particle level spacing is not negligible. It is shown that, for a
superconducting ring with even parity, the behavior of persistent current is
equivalent to what is expected in a bulk superconducting ring. On the other
hand, we find that a ring with odd parity shows anomalous behavior such as
fluxoid quantization at half-integral multiples of the flux quantum and
paramagnetic response at low temperature. We also discuss how the parity effect
in the persistent current disappears as the temperature is raised or as the
size of the ring increases.

</DOC>
<DOC>
<DOCNO> 9559 </DOCNO>
The Lattice Schwinger Model: Confinement, Anomalies, Chiral Fermions and


  In order to better understand what to expect from numerical CORE computations
for two-dimensional massless QED (the Schwinger model) we wish to obtain some
analytic control over the approach to the continuum limit for various choices
of fermion derivative. To this end we study the Hamiltonian formulation of the
lattice Schwinger model (i.e., the theory defined on the spatial lattice with
continuous time) in $A_0=0$ gauge. We begin with a discussion of the solution
of the Hamilton equations of motion in the continuum, we then parallel the
derivation of the continuum solution within the lattice framework for a range
of fermion derivatives. The equations of motion for the Fourier transform of
the lattice charge density operator show explicitly why it is a regulated
version of this operator which corresponds to the point-split operator of the
continuum theory and the sense in which the regulated lattice operator can be
treated as a Bose field. The same formulas explicitly exhibit operators whose
matrix elements measure the lack of approach to the continuum physics. We show
that both chirality violating Wilson-type and chirality preserving SLAC-type
derivatives correctly reproduce the continuum theory and show that there is a
clear connection between the strong and weak coupling limits of a theory based
upon a generalized SLAC-type derivative.

</DOC>
<DOC>
<DOCNO> 170586 </DOCNO>
Quantum computing by pairing trapped ultracold ions


  The superpositional wave function oscillations for finite-time implementation
of quantum algorithms modifies the desired interference required for quantum
computing. We propose a scheme with trapped ultracold ion-pairs being qubits to
diminish the detrimental effect of the wave function oscillations, and apply
the scheme to the two-qubit Grover's search. It can be also found that the
qubits in our scheme are more robust against the decoherence caused by the
environment, and the model is scalable.

</DOC>
<DOC>
<DOCNO> 9850 </DOCNO>
Plasma dispersion of multisubband electron systems over liquid helium


  Density-density response functions are evaluated for nondegenerate
multisubband electron systems in the random-phase approximation for arbitrary
wave number and subband index. We consider both quasi-two-dimensional and
quasi-one- dimensional systems for electrons confined to the surface of liquid
helium. The dispersion relations of longitudinal intrasubband and transverse
intersubband modes are calculated at low temperatures and for long wavelengths.
We discuss the effects of screening and two-subband occupancy on the plasmon
spectrum. The characteristic absorption edge of the intersubband modes is
shifted relatively to the single-particle intersubband separation and the
depolarization shift correction can be significant at high electron densities.

</DOC>
<DOC>
<DOCNO> 121376 </DOCNO>
Physical Conditions in Circumstellar Gas surrounding SN 1987A 12 Years


  Two-dimensional spectra of Supernova 1987A were obtained on 1998 November
14-15 (4282 days after outburst) with the Space Telescope Imaging Spectrograph
(STIS) on board the Hubble Space Telescope (HST). The slit sampled portions of
the inner circumstellar ring at the east and west ansae as well as small
sections of both the northern and southern outer rings. The temperature and
density at these locations are estimated by nebular analysis of [N II], [O
III], and [S II] emission line ratios, and with time-dependent
photoionization/recombination models. The results from these two methods are
mutually consistent. The electron density in the inner ring is ~ 4000 cm-3 for
S II, with progressively lower densities for N II and O III. The electron
temperatures determined from [N II] and [O III] line ratios are ~11,000 K and
\~22,000 K, respectively. These results are consistent with evolutionary trends
in the circumstellar gas from similar measurements at earlier epochs. We find
that emission lines from the outer rings come from gas of lower density (n_e
\la 2000 cm-3) than that which emits the same line in the inner ring. The N/O
ratio appears to be the same in all three rings. Our results also suggest that
the CNO abundances in the northern outer ring are the same as in the inner
ring, contrary to earlier results of Panagia et al. (1996). Physical conditions
in the southern outer ring are less certain because of poorer signal-to-noise
data. The STIS spectra also reveal a weak Ha emission redshifted by ~100 km s-1
at p.a. 103\arcdeg that coincides with the recently discovered new regions that
are brightening (Lawrence et al. 2000). This indicates that the shock
interaction in the SE section of the inner ring commenced over a year before it
became apparent in HST images.

</DOC>
<DOC>
<DOCNO> 118282 </DOCNO>
Time Resolved GRB Spectroscopy


  We present the main results of a study of time-resolved spectra of 43 intense
GRBs detected by BATSE. We considered the 4-parameter Band model and the
Optically Thin Synchrotron Shock model (OTSSM). We find that the large majority
of time-resolved spectra of GRBs are in remarkable agreement with the OTSSM.
However, about 15 % of initial GRB pulses show an apparent low-energy photon
suppression. This phenomenon indicates that complex radiative conditions
modifying optically thin emission may occur during the initial phases of some
GRBs.

</DOC>
<DOC>
<DOCNO> 120610 </DOCNO>
First Results from the X-ray and Optical Survey of the Chandra Deep


  We present our first results from 130 ks of X-ray observations obtained with
the Advanced CCD Imaging Spectrometer on the Chandra X-ray Observatory. We
reach a flux of 2 X 10^(-16) erg s^(-1) cm^(-2) in the 0.5-2 keV soft band and
2 X 10^(-15) erg s^(-1) cm^(-2) in the 2-10 keV hard band. For the optical
identification we carried out a survey in VRI with the FORS-1
imaging-spectrometer on the ANTU telescope (UT-1 at VLT) complete to R <= 26.
This dataset was complemented with data from the ESO Imaging Survey (EIS) in
the UBJK bands and the ESO Wide Field Imager Survey (WFI) in the B band. The
positional accuracy of the X-ray detections is of order of 1'' in the central
6'. Optical identifications are found for ~90% of the sources. We obtain the
cumulative spectra of the faint and bright X-ray sources in the sample. A power
law fit in the range 2-10 keV using the galactic value of N_H ~ 8 x 10^(19)
cm^(-2), yields a photon index of Gamma = 1.70+-0.06 and 1.35+-0.10 for the
bright and faint sample respectively, showing a flattening of the spectrum at
lower fluxes. We discuss the LogN-LogS relationship and the discrete source
contribution to the integrated X-ray sky flux. In the soft band, the sources
now detected at fluxes below 10^(-15) erg s^(-1) cm^(-2) contribute (4.0 +-
0.3) X 10^(-12) erg cm^(-2)s^(-1) deg^(-2) to the total XRB. The flux resolved
in the hard band down to the flux limit of 2 X 10^(-15) erg s^(-1) cm^(-2) now
contributes a total of 1.6 X 10^(-11) erg cm^(-2) s^(-1) deg^(-2) which amounts
to a fraction of 60-80% of the total measured background. This result confirms
that the XRB is due to the integrated contribution of discrete sources, but
shows that there is still a relevant fraction (at least 20%) of the hard XRB to
be resolved at fluxes below 10^(-15) erg s^(-1) cm^(-2). (ABRIDGED)

</DOC>
<DOC>
<DOCNO> 40620 </DOCNO>
Large Standard Model Higgs at LEP


  In 1999 the LEP experiments collected data at centre of mass energies between
192 and 202 GeV for about 900 pb-1 integrated luminosity. Combined results are
presented for the search for the Standard Model Higgs boson. No statistically
significant excess has been observed when compared to Standard Model background
expectation which can be translated into a lower bound on the mass of the Higgs
boson at 107.9 GeV/c^2 at 95 % confidence level.

</DOC>
<DOC>
<DOCNO> 121341 </DOCNO>
Geometrical estimators as a test of Gaussianity in the CMB


  We investigate the power of geometrical estimators on detecting
non-Gaussianity in the cosmic microwave background. In particular the number,
eccentricity and Gaussian curvature of excursion sets above (and below) a
threshold are studied. We compare their different performance when applied to
non-Gaussian simulated maps of small patches of the sky, which take into
account the angular resolution and instrumental noise of the Planck satellite.
These non-Gaussian simulations are obtained as perturbations of a Gaussian
field in two different ways which introduce a small level of skewness or
kurtosis in the distribution. A comparison with a classical estimator, the
genus, is also shown. We find that the Gaussian curvature is the best of our
estimators in all the considered cases. Therefore we propose the use of this
quantity as a particularly useful test to look for non-Gaussianity in the CMB.

</DOC>
<DOC>
<DOCNO> 68103 </DOCNO>
Fermion production during preheating after hybrid inflation


  At the end of inflation, the coherent oscillations of the inflaton field may
resonantly amplify the long wavelength modes of both bosons and fermions
coupled to it. We study the resonant production of both kinds of particles
during preheating in a model of hybrid inflation. The coherent time evolution
of the inflaton and the Higgs fields after inflation induce a very different
production of fermions depending on whether they are coupled to the Higgs or to
the inflaton. For reasonable values of the model parameters, the fermion
production through parametric resonance can be very efficient. We study the
relative growth of the fermion and boson energy densities during preheating in
hybrid models. During the initial stage of preheating, fermion production
dominates the relative energy density, while the exponential growth of bosonic
modes soon takes over.

</DOC>
<DOC>
<DOCNO> 84240 </DOCNO>
Nonthermal nature of incipient extremal black holes


  We examine particle production from spherical bodies collapsing into extremal
Reissner-Nordstr\"om black holes. Kruskal coordinates become ill-defined in the
extremal case, but we are able to find a simple generalization of them that is
good in this limit. The extension allows us to calculate the late-time
worldline of the center of the collapsing star, thus establishing a
correspondence with a uniformly accelerated mirror in Minkowski spacetime. The
spectrum of created particles associated with such uniform acceleration is
nonthermal, indicating that a temperature is not defined. Moreover, the
spectrum contains a constant that depends on the history of the collapsing
object. At first sight this points to a violation of the no-hair theorems;
however, the expectation value of the stress-energy-momentum tensor is zero and
its variance vanishes as a power law at late times. Hence, both the no-hair
theorems and the cosmic censorship conjecture are preserved. The power-law
decay of the variance is in distinction to the exponential fall-off of a
nonextremal black hole. Therefore, although the vanishing of the stress
tensor's expectation value is consistent with a thermal state at zero
temperature, the incipient black hole does not behave as a thermal object at
any time and cannot be regarded as the thermodynamic limit of a nonextremal
black hole, regardless of the fact that the final product of collapse is
quiescent.

</DOC>
<DOC>
<DOCNO> 116403 </DOCNO>
Ortho-Para Conversion in CH3F. Self-Consistent Theoretical Model


  A complete theoretical model of the nuclear spin conversion in 13CH3F induced
by intramolecular ortho-para state mixing is proposed. The model contains
parameters determined from the level-crossing spectra of the 13CH3F spin
conversion. This set of parameters includes the ortho-para decoherence rate,
the magnitude of the hyperfine spin-spin interaction between the molecular
nuclei and the energy gap between the mixed ortho and para states. These
parameters are found to be in a good agreement with their theoretical
estimates.

</DOC>
<DOC>
<DOCNO> 100408 </DOCNO>
Restoring Fairness to Dukego


  In this paper we correct an analysis of the two-player perfect-information
game Dukego given in Berlekamp, Conway, and Guy's Winning Ways for your
Mathematical Plays (Chapter 19). In particular, we characterize the board
dimensions that are fair, i.e., those for which the first player to move has a
winning strategy.

</DOC>
<DOC>
<DOCNO> 152473 </DOCNO>
Noncommutative ${\cal N}=1,2$ super U(N) Yang-Mills: UV/IR mixing and


  Noncommutative ${\cal N}=1$ and ${\cal N}=2$ supersymmetric Yang-Mills
theories with gauge group U(N) are studied here using the background field
method and superspace background covariant D-algebra in perturbation theory. At
one loop divergences arise only in the two-point functions. They are
logarithmic UV/IR divergences in the planar/nonplanar sectors that play a role
dual to each other. We compute the planar and non planar contributions to the
three- and four-point functions with vector external lines. We find that the
three-point function vanishes, while the four-point function receives
contributions both from vector and from chiral matter loops.

</DOC>
<DOC>
<DOCNO> 83184 </DOCNO>
Mathematical Software: Past, Present, and Future


  This paper provides some reflections on the field of mathematical software on
the occasion of John Rice's 65th birthday. I describe some of the common themes
of research in this field and recall some significant events in its evolution.
Finally, I raise a number of issues that are of concern to future developments.

</DOC>
<DOC>
<DOCNO> 8203 </DOCNO>
Collective excitation frequencies of Bosons in a parabolic potential


  The fact that the ground-state first-order density matrix for Bosons in a
parabolic potential with interparticle harmonic interactions is known in exact
form is here exploited to study collective excitations in the weak-coupling
regime. Oscillations about the ground-state density are treated analytically by
a linearized equation of motion which includes a kinetic energy contribution.
We show that the dipole mode has the frequency of the bare trap, in accord with
the Kohn theorem, and derive explicit expressions for the frequencies of the
higher-multipole modes in terms of a frequency renormalized by the
interactions.

</DOC>
<DOC>
<DOCNO> 13364 </DOCNO>
Angle-resolved photoemission study of insulating and metallic Cu-O


  We compare the angle-resolved photoemission spectra of the hole-doped Cu-O
chains in PrBa$_2$Cu$_3$O$_7$ (Pr123) and in PrBa$_2$Cu$_4$O$_8$ (Pr124).
While, in Pr123, a dispersive feature from the chain takes a band maximum at
$k_b$ (momentum along the chain) $\sim$ $\pi/4$ and loses its spectral weight
around the Fermi level, it reaches the Fermi level at $k_b$ $\sim$ $\pi/4$ in
Pr124. Although the chains in Pr123 and Pr124 are approximately 1/4-filled,
they show contrasting behaviors: While the chains in Pr123 have an instability
to charge ordering, those in Pr124 avoid it and show an interesting spectral
feature of a metallic coupled-chain system.

</DOC>
<DOC>
<DOCNO> 101858 </DOCNO>
Estimated transversality in symplectic geometry and projective maps


  The main theorem of this paper is a result of estimated transversality with
respect to stratifications of jet spaces in the approximately holomorphic
category over an almost-complex manifold. The notion of asymptotic ampleness of
complex vector bundles over an almost-complex manifold is also discussed, as
well as applications to the construction of maps with generic singularities
from compact symplectic manifolds to projective spaces.

</DOC>
<DOC>
<DOCNO> 40009 </DOCNO>
Can CPT Symmetry Be Tested With K^0 vs \bar{K}^0--> \pi^+\pi^-\pi^0


  We show that the CP-violating effect in K^0 vs \bar K^0-->\pi^+\pi^-\pi^0
decays differs from that in K_{\rm L}-->\pi^+\pi^-, K_{\rm L}-->\pi^0\pi^0 or
the semileptonic K_{\rm L} transitions, if there exists CPT violation in
K^0-\bar{K}^0 mixing. A delicate measurement of this difference in the KTeV
experiment and at the \phi factory will provide a new test of CPT symmetry in
the neutral kaon system.

</DOC>
<DOC>
<DOCNO> 9563 </DOCNO>
Stock Market Speculation: Spontaneous Symmetry Breaking of Economic


  Firm foundation theory estimates a security's firm fundamental value based on
four determinants: expected growth rate, expected dividend payout, the market
interest rate and the degree of risk. In contrast, other views of
decision-making in the stock market, using alternatives such as human
psychology and behavior, bounded rationality, agent-based modeling and
evolutionary game theory, expound that speculative and crowd behavior of
investors may play a major role in shaping market prices. Here, we propose that
the two views refer to two classes of companies connected through a ``phase
transition''. Our theory is based on 1) the identification of the fundamental
parity symmetry of prices ($p \to -p$), which results from the relative
direction of payment flux compared to commodity flux and 2) the observation
that a company's risk-adjusted growth rate discounted by the market interest
rate behaves as a control parameter for the observable price. We find a
critical value of this control parameter at which a spontaneous
symmetry-breaking of prices occurs, leading to a spontaneous valuation in
absence of earnings, similarly to the emergence of a spontaneous magnetization
in Ising models in absence of a magnetic field. The low growth rate phase is
described by the firm foundation theory while the large growth rate phase is
the regime of speculation and crowd behavior. In practice, while large
``finite-time horizon'' effects round off the predicted singularities, our
symmetry-breaking speculation theory accounts for the apparent over-pricing and
the high volatility of fast growing companies on the stock markets.

</DOC>
<DOC>
<DOCNO> 152313 </DOCNO>
Renormalization of composite operators


  The blocked composite operators are defined in the one-component Euclidean
scalar field theory, and shown to generate a linear transformation of the
operators, the operator mixing. This transformation allows us to introduce the
parallel transport of the operators along the RG trajectory. The connection on
this one-dimensional manifold governs the scale evolution of the operator
mixing. It is shown that the solution of the eigenvalue problem of the
connection gives the various scaling regimes and the relevant operators there.
The relation to perturbative renormalization is also discussed in the framework
of the $\phi^3$ theory in dimension $d=6$.

</DOC>
<DOC>
<DOCNO> 118688 </DOCNO>
HS0907+1902: a new 4.2hr eclipsing dwarf nova


  We report on follow-up spectroscopy and photometry of the cataclysmic
variable candidate HS0907+1902 selected from the Hamburg Quasar Survey. B, V,
and R photometry obtained during the first observed outburst of HS0907+1902
(V~13) reveals deep eclipses (DeltaV~2.1-2.8) and an orbital period Porb=4.2h
with the eclipse depth decreasing to the red. The outburst eclipse profiles are
symmetric, indicating an axisymmetrical brightness distribution in the
accretion disc. We derive an inclination i~73deg-79deg from the eclipse
duration. The quiescent spectrum obtained with the Hobby-Eberly Telescope shows
double peaked emission lines of HI, HeI and FeI,II and clearly identifies the
system as a dwarf nova. Absorption features of the secondary star are detected
at red wavelengths from which a spectral class M3+-1.5 and a distance of
d=320+-100pc are derived.

</DOC>
<DOC>
<DOCNO> 151177 </DOCNO>
D-Branes and their Absorptivity in Born-Infeld Theory


  Standard methods of nonlinear dynamics are used to investigate the stability
of particles, branes and D-branes of abelian Born-Infeld theory. In particular
the equation of small fluctuations about the D-brane is derived and converted
into a modified Mathieu equation and - complementing earlier low-energy
investigations in the case of the dilaton-axion system - studied in the
high-energy domain. Explicit expressions are derived for the S-matrix and
absorption and reflection amplitudes of the scalar fluctuation in the presence
of the D-brane. The results confirm physical expectations and numerical studies
of others. With the derivation and use of the (hitherto practically unknown)
high energy expansion of the Floquet exponent our considerations also close a
gap in earlier treatments of the Mathieu equation.

</DOC>
<DOC>
<DOCNO> 67836 </DOCNO>
Resonant Slepton Production at the LHC


  We consider the resonant production of charged sleptons at the LHC via
R-parity violation followed by gauge decays to a charged lepton and a
neutralino which then decays via R-parity violation. This gives a signature of
two like-sign charged leptons. In the simulation we include the full
hadronisation via Monte Carlo programs. We find a background, after cuts, of
5.1+/-2.5 events for an integrated luminosity of 10 fb^-1. A preliminary study
of the signal suggests that couplings of 2.10^-3 for a smuon mass of 223 GeV
and smuon masses of up to 540 GeV for couplings of 10^-2 can be probed.

</DOC>
<DOC>
<DOCNO> 117875 </DOCNO>
Collisional versus Collisionless Dark Matter


  We compare the structure and substructure of dark matter halos in model
universes dominated by collisional, strongly self interacting dark matter
(SIDM) and collisionless, weakly interacting dark matter (CDM). While SIDM
virialised halos are more nearly spherical than CDM halos, they can be
rotationally flattened by as much as 20% in their inner regions. Substructure
halos suffer ram-pressure truncation and drag which are more rapid and severe
than their gravitational counterparts tidal stripping and dynamical friction.
Lensing constraints on the size of galactic halos in clusters are a factor of
two smaller than predicted by gravitational stripping, and the recent detection
of tidal streams of stars escaping from the satellite galaxy Carina suggests
that its tidal radius is close to its optical radius of a few hundred parsecs
--- an order of magnitude smaller than predicted by CDM models but consistent
with SIDM. The orbits of SIDM satellites suffer significant velocity bias
$\sigma_{SIDM}/\sigma_{CDM}=0.85$ and are more circular than CDM,
$\beta_{SIDM}} \approx 0.5$, in agreement with the inferred orbits of the
Galaxy's satellites. In the limit of a short mean free path, SIDM halos have
singular isothermal density profiles, thus in its simplest incarnation SIDM is
inconsistent with galactic rotation curves.

</DOC>
<DOC>
<DOCNO> 117319 </DOCNO>
Biology and Thermodynamics: Seemingly-Opposite Phenomena in Search of a


  It is probably not a coincidence that two of the pioneers of thermodynamics,
Helmholtz and Mayer, were physicians. Thermodynamics studies the
transformations of energy, and such transformations ceaselessly take place in
all living systems (probably with important differences between the states of
health and disease). Moreover, thermodynamics studies the elusive notions of
order and disorder, which are also, respectively, the very hallmarks of life
and death. These similarities suggest that thermodynamics might provide a
unifying paradigm for many life sciences, explaining the multitude of life's
manifestations on the basis of a few basic physical principles. In this article
we introduce some basic thermodynamic concepts and point out their usefulness
for the biologist and the physician. We hope to show that thermodynamics
enables looking at the riddles of life from a new perspective and asking some
new fruitful questions.

</DOC>
<DOC>
<DOCNO> 84217 </DOCNO>
Symmetry Breaking, Central Charges and the AdS_2/CFT_1 Correspondence


  When two-dimensional Anti-de Sitter space (AdS_2) is endowed with a
non-constant dilaton the origin of the central charge in the Virasoro algebra
generating the asymptotic symmetries of AdS_2 can be traced back to the
breaking of the SL(2,R) isometry group of AdS_2. We use this fact to clarify
some controversial results appeared in the literature about the value of the
central charge in these models.

</DOC>
<DOC>
<DOCNO> 11110 </DOCNO>
Holographic Bound from Second Law


  The holographic bound that the entropy (log of number of quantum states) of a
system is bounded from above by a quarter of the area of a circumscribing
surface measured in Planck areas is widely regarded a desideratum of any
fundamental theory, but some exceptions occur. By suitable black hole gedanken
experiments I show that the bound follows from the generalized second law for
two broad classes of isolated systems: generic weakly gravitating systems
composed of many elementary particles, and quiescent, nonrotating strongly
gravitating configurations well above Planck mass. These justify an early claim
by Susskind.

</DOC>
<DOC>
<DOCNO> 9812 </DOCNO>
Shear response of a frictional interface to a normal load modulation


  We study the shear response of a sliding multicontact interface submitted to
a harmonically modulated normal load, without loss of contact. We measure, at
low velocities ($V<100 \mu$m.s$^{-1}$), the average value $\bar{F}$ of the
friction force and the amplitude of its first and second harmonic components.
The excitation frequency ($f=120$ Hz) is chosen much larger than the natural
one, associated to the dynamical ageing of the interface. We show that: (i) In
agreement with the engineering thumb rule, even a modest modulation induces a
substantial decrease of $\bar{F}$. (ii) The Rice-Ruina state and rate model,
though appropriate to describe the slow frictional dynamics, must be extended
when dealing with our ``high'' frequency regime. Namely, the rheology which
controls the shear strength must explicitly account not only for the plastic
response of the adhesive junctions between load-bearing asperities, but also
for the elastic contribution of the asperities bodies. This ``elasto-plastic''
friction model leads to predictions in excellent quantitative agreement with
all our experimental data.

</DOC>
<DOC>
<DOCNO> 84441 </DOCNO>
Darboux class of cosmological fluids with time-dependent adiabatic


  A one-parameter family of time dependent adiabatic indices is introduced for
any given type of cosmological fluid of constant adiabatic index by a
mathematical method belonging to the class of Darboux transformations. The
procedure works for zero cosmological constant at the price of introducing a
new constant parameter related to the time dependence of the adiabatic index.
These fluids can be the real cosmological fluids that are encountered at
cosmological scales and they could be used as a simple and efficient
explanation for the recent experimental findings regarding the present day
accelerating universe. In addition, new types of cosmological scale factors,
corresponding to these fluids, are presented

</DOC>
<DOC>
<DOCNO> 150437 </DOCNO>
S and U-duality Constraints on IIB S-matrices


  S and U-duality dictate that graviton scattering amplitudes in IIB
superstring theory be automorphic functions on the appropriate fundamental
domain which describe the inequivalent vacua of (compactified) theories. A
constrained functional form of graviton scattering is proposed using Eisenstein
series and their generalizations compatible with: a) two-loop supergravity, b)
genus one superstring theory, c) the perturbative coupling dependence of the
superstring, and d) with the unitarity structure of the massless modes. The
form has a perturbative truncation in the genus expansion at a given order in
the derivative expansion. Comparisons between graviton scattering S-matrices
and effective actions for the first quantized superstring are made at the
quantum level. Possible extended finiteness properties of maximally extended
quantum supergravity theories in different dimensions is implied by the
perturbative truncation of the functional form of graviton scattering in IIB
superstring theory.

</DOC>
<DOC>
<DOCNO> 69124 </DOCNO>
Neutrino masses in the R-parity violating MSSM


  We compute one loop neutrino masses in the R-parity violating Minimal
Supersymmetric Model, including the bilinear R-parity violating masses in the
mass insertion approximation. To the order we calculate, our results are
independent of the Higgs-lepton basis choice. We have a variety of perturbative
parameters-gauge, yukawa and trilinear couplings, and R_p violating masses.
Their relative magnitudes determine which diagrams are relevant for neutrino
mass calculations. We find new loop diagrams which can be relevant and have
frequently been neglected in the past. For the Grossman-Haber neutral loop
contribution to the neutrino mass matrix we obtain explicit analytic results.

</DOC>
<DOC>
<DOCNO> 11816 </DOCNO>
Unified Description of the Resonance Peak and Incommensuration in


  We present a unified description of the resonance peak and low-energy
incommensurate response observed in high-$T_c$ cuprate superconductors. We
argue that both features have a purely magnetic origin and they represent
universal features of an incommensurate spin state both below and above the
superconducting transition temperature. In this description the resonance peak
is the reflection of commensurate antiferromagnetism. Our theoretical scenario
gives an account of the main features observed in various families of
superconductors and predicts those not yet observed, like a resonance peak in
La$_2$NiO$_{4+x}$.

</DOC>
<DOC>
<DOCNO> 151037 </DOCNO>
Two dimensional fractional supersymmetric conformal field theories and


  A general two dimensional fractional supersymmetric conformal field theory is
investigated. The structure of the symmetries of the theory is studied. Then,
applying the generators of the closed subalgebra generated by $(L_{-1}, L_{0},
G_{-1/3})$ and $(\bar{L}_{-1}, \bar{L}_{0}, \bar{G}_{-1/3})$, the two point
functions of the component fields of supermultiplets are calculated.

</DOC>
<DOC>
<DOCNO> 122572 </DOCNO>
Peering through the dust: Evidence for a supermassive Black Hole at the


  We used the near infrared spectrometer ISAAC at the ESO 'Very Large
Telescope' to map the velocity field of Centaurus A (NGC 5128) at several
position angles and locations in the central 20" of the galaxy. The high
spatial resolution (~0.5") velocity fields from both ionized and molecular gas
(PaBeta, [FeII], BrGamma, and H2) are not compromised by either excitation
effects or obscuration. We identify three distinct kinematical systems: (i) a
rotating 'nuclear disk' of ionized gas, confined to the inner 2", the
counterpart of the PaAlpha feature previously revealed by HST/NICMOS imaging;
(ii) a ring-like system with a ~6" inner radius detected only in H2, likely the
counterpart of the 100pc-scale structure detected in CO by other authors; (iii)
a normal extended component of gas rotating in the galactic potential. The
nuclear disk is in keplerian rotation around a central mass concentration, dark
(M/L>20 Msun/LsunK) and point-like at the spatial resolution of the data
(R<0.25" ~4pc). We interpret this mass concentration as a supermassive black
hole. Its dynamical mass based on the line velocities and disk inclination
(i>15deg) is M=2(+3.0;-1.4) 10^8 Msun. The ring-like system is probably
characterized by non-circular motions; a 'figure-of-8' pattern observed in the
H2 position-velocity diagram might provide kinematical evidence for the
presence of a nuclear bar.

</DOC>
<DOC>
<DOCNO> 70822 </DOCNO>
Supernova data may be unable to distinguish between quintessence and


  We consider the efficacy of using luminosity distance measurements of deep
redshift supernovae to discriminate between two forms of dark energy,
quintessence (a scalar field with canonical kinetic terms rolling down a
potential) and k-essence (a scalar field whose cosmic evolution is driven
entirely by non-linear kinetic terms). The primary phenomenological distinction
between the two types of models that can be quantified by supernova searches
(at least in principle) is that the equation of state $w\equiv p/\rho$ of
quintessence is falling today while that of k-essence is rising. By simulating
$10^5$ possible datasets that SNAP could obtain, we show that even if the mass
density $\Omega_m$ is known exactly, an ambiguity remains that may not allow a
definitive distinction to be made between the two types of theories.

</DOC>
<DOC>
<DOCNO> 71988 </DOCNO>
An electroweak library for the calculation of EWRC to e+ e- --> f fbar


  We present a description of calculations of the electroweak amplitude for e+
e- --> f fbar process. The calculations are done within the OMS (on-mass-shell)
renormalization scheme in two gauges: in Rxi, which allows an explicit control
of gauge invariance by examining cancellation of gauge parameters and search
for gauge-invariant subsets of diagrams, and in the unitary gauge as a
cross-check. The formulae we derived are realized in a FORTRAN code eeffLib,
which is being created within the framework of the project CalcPHEP. We present
a comprehensive comparison between eeffLib results for the light top with
corresponding results of the well-known program ZFITTER for the u ubar channel,
as well as a preliminary comparison with results existing in the world
literature.

</DOC>
<DOC>
<DOCNO> 70396 </DOCNO>
Meson loop effects in the NJL model at zero and non-zero temperature


  We compare two different possibilities to include meson-loop corrections in
the Nambu-Jona-Lasinio model: a strict 1/N_c-expansion in next-to-leading order
and a non-perturbative scheme corresponding to a one-meson-loop approximation
to the effective action. Both schemes are consistent with chiral symmetry, in
particular with the Goldstone theorem and the Gell-Mann-Oakes-Renner relation.
The numerical part at zero temperature focuses on the pion and the rho-meson
sector. For the latter the meson-loop-corrections are crucial in order to
include the dominant rho -> pipi-decay channel, while the standard Hartree +
RPA approximation only contains unphysical qqbar-decay channels. We find that
m_\pi, f_\pi, <qbar q> and quantities related to the rho-meson self-energy can
be described reasonably with one parameter set in the 1/N_c-expansion scheme,
whereas we did not succeed to obtain such a fit in the non-perturbative scheme.
We also investigate the temperature dependence of the quark condensate. Here we
find consistency with chiral perturbation theory to lowest order. Similarities
and differences of both schemes are discussed.

</DOC>
<DOC>
<DOCNO> 151889 </DOCNO>
Poincar\'e covariance of relativistic quantum position


  A great number of problems of relativistic position in quantum mechanics are
due to the use of coordinates which are not inherent objects of spacetime,
cause unnecessary complications and can lead to misconceptions. We apply a
coordinate-free approach to rule out such problems. Thus it will be clear, for
example, that the Lorentz covariance of position, required usually on the
analogy of Lorentz covariance of spacetime coordinates, is not well posed and
we show that in a right setting the Newton--Wigner position is Poincar\'e
covariant, in contradiction with the usual assertions.

</DOC>
<DOC>
<DOCNO> 121531 </DOCNO>
The evolution of the Milky Way monitored in the solar neighbourhood


  In this review we concentrate on the dynamical evolution of the Milky Way as
monitored in the solar neighbourhood. The relevant data sets are presented and
discussed in detail. In the second part we review various mechanisms, which
drive the dynamical evolution.

</DOC>
<DOC>
<DOCNO> 11768 </DOCNO>
Fractal distribution function and fractal-deformed Heisenberg algebras


  We consider the concept of fractons, i.e. particles or quasiparticles which
obey specific fractal distribution function and for each universal class h of
particles we obtain a fractal-deformed Heisenberg algebra. This one takes into
account the braid group structure of these objects which live in
two-dimensional multiply connected space.

</DOC>
<DOC>
<DOCNO> 120698 </DOCNO>
The Redshift and the Host Galaxy of GRB 980613: A Gamma-Ray Burst From a


  We present optical and near-IR identification and spectroscopy of the host
galaxy of GRB 980613. The burst was apparently associated with the optically
(restframe UV) brightest component of a system of at least five galaxies or
galaxy fragments at a redshift of z = 1.0969. The component we identify as the
host galaxy shows a moderately high unobscured star formation rate, SFR = 5
M_solar/yr, but a high SFR per unit mass, indicative of a starburst. The image
components show a broad range of (R-K) colors, with two of them being very red,
possibly due to dust. Overall morphology of the system can be naturally
interpreted as a strong tidal interaction of two or more galaxies, at a
redshift where such events were much more common than now. Given the well
established causal link between galaxy mergers and starbursts, we propose that
this is a strong case for a GRB originating from a merger-induced starburst
system. This supports the proposed link between GRBs and massive star
formation.

</DOC>
<DOC>
<DOCNO> 69550 </DOCNO>
Pythia version 7-0.0 - a proof-of-concept version


  This document describes the first proof-of-concept version of the Pythia7
program.
  Pythia7 is a complete re-write of the Pythia program in C++. It is mainly
intended to be a replacement for the `Lund' family of event generators, but is
also a toolkit with a structure suitable for implementing any event generator
model.
  In this document, the structure of the program is presented both from the
user and the developer point of view. It is not intended to be a complete
manual, but together with the documentation provided in the distribution, it
should be sufficient to start working with the program.

</DOC>
<DOC>
<DOCNO> 150429 </DOCNO>
Representations of (1,0) and (2,0) superconformal algebras in six


  We construct unitary representations of (1,0) and (2,0) superconformal
algebras in six dimensions by using superfields defined on harmonic superspaces
with coset manifolds USp(2n)/[U(1)]^n, n=1,2. In the spirit of the AdS_7/CFT_6
correspondence massless conformal fields correspond to "supersingletons" in
AdS_7. By tensoring them we produce all short representations corresponding to
1/2 and 1/4 BPS anti-de Sitter bulk states of which "massless bulk"
representations are particular cases.

</DOC>
<DOC>
<DOCNO> 117954 </DOCNO>
Formation of intermediate-mass black holes in circumnuclear regions of


  Recent high-resolution X-ray imaging studies have discovered possible
candidates of intermediate-mass black holes with masses of $M_\bullet \sim
10^{2-4} \MO$ in circumnuclear regions of many (disk) galaxies. It is known
that a large number of massive stars are formed in a circumnuclear giant H {\sc
ii} region. Therefore, we propose that continual merger of compact remnants
left from these massive stars is responsible for the formation of such an
intermediate-mass black hole within a timescale of $\sim 10^9$ years. A
necessary condition is that several hundreds of massive stars are formed in a
compact region with a radius of a few pc.

</DOC>
<DOC>
<DOCNO> 8144 </DOCNO>
The theory of GMR and TMR in segmented magnetic nanowires


  We calculate the resistivity and Giant Magnetoresistance (GMR) of a segmented
nanowire consisting of two ferromagnetic segments separated by a thin
paramagnetic spacer. The quantization of the electron motion due to the small
nanowire cross-section is taken into account; s-d electron scattering gives
rise to different mean free paths for spin-up and spin-down s-electrons. The
calculated resistivity and GMR oscillate as a function of nanowire
cross-section due to the difference in Fermi momenta of d-electrons with
opposite spins. The GMR can reach values much higher than those which are
obtained for "wires" of infinite cross-section (i.e., a multilayer). Similarly
we have calculated the Tunneling Magnetoresistance (TMR) by replacing the
paramagnetic spacer with an insulator spacer.

</DOC>
<DOC>
<DOCNO> 13065 </DOCNO>
Momentum flux density, kinetic energy density and their fluctuations for


  We present a Green's function method for the evaluation of the particle
density profile and of the higher moments of the one-body density matrix in a
mesoscopic system of N Fermi particles moving independently in a linear
potential. The usefulness of the method is illustrated by applications to a
Fermi gas confined in a harmonic potential well, for which we evaluate the
momentum flux and kinetic energy densities as well as their quantal mean-square
fluctuations. We also study some properties of the kinetic energy functional
E_{kin}[n(x)] in the same system. Whereas a local approximation to the kinetic
energy density yields a multi-valued function, an exact single-valued
relationship between the density derivative of E_{kin}[n(x)] and the particle
density n(x) is demonstrated and evaluated for various values of the number of
particles in the system.

</DOC>
<DOC>
<DOCNO> 117857 </DOCNO>
Gamma-Ray Bursts in the 1990's - a Multi-wavelengths Scientific


  In 1997 the first optical afterglow of a cosmic Gamma-Ray Burst was
discovered, and substantial progress has been achieved since then. Here we
present a short review of some recent developments in this field, with emphasis
on observational aspects of the GRB phenomenon.

</DOC>
<DOC>
<DOCNO> 119528 </DOCNO>
Unravelling Active Galactic Nuclei


  A complete flat-spectrum radio-loud sample of AGN includes a significant
fraction of Seyfert-like AGN including a NLS1. Analysis of their optical
spectra suggests that the reddest continuum colours are either associated with
AGN in nearby resolved galaxies, or distant quasars showing relatively narrow
permitted emission lines.

</DOC>
<DOC>
<DOCNO> 70702 </DOCNO>
Light-Cone Wavefunction Representation of Deeply Virtual Compton


  We give a complete representation of virtual Compton scattering $\gamma^* p
\to \gamma p$ at large initial photon virtuality $Q^2$ and small momentum
transfer squared $t$ in terms of the light-cone wavefunctions of the target
proton. We verify the identities between the skewed parton distributions
$H(x,\zeta,t)$ and $E(x,\zeta,t)$ which appear in deeply virtual Compton
scattering and the corresponding integrands of the Dirac and Pauli form factors
$F_1(t)$ and $F_2(t)$ and the gravitational form factors $A_{q}(t)$ and
$B_{q}(t)$ for each quark and anti-quark constituent. We illustrate the general
formalism for the case of deeply virtual Compton scattering on the quantum
fluctuations of a fermion in quantum electrodynamics at one loop.

</DOC>
<DOC>
<DOCNO> 84571 </DOCNO>
Entropies of Rotating Charged Black Holes from Conformal Field Theory at


  The covariant phase technique is used to compute the constraint algebra of
the stationary axisymmetric charged black hole. A standard Virasoro subalgebra
with corresponding central charge is constructed at a Killing horizon with
Carlip's boundary conditions. For the Kerr-Newman black hole and the
Kerr-Newman-AdS black hole, the density of states determined by conformal
fields theory methods yields the statistical entropy which agrees with the
Bekenstein-Hawking entropy.

</DOC>
<DOC>
<DOCNO> 178811 </DOCNO>
Medium effects on the flow of strange particles in heavy ion collisions


  Strange particles such as the kaon and lambda are useful in probing the
properties of dense matter formed in heavy ion collisions. We review in this
talk the theoretical understandings of their properties in nuclear medium based
on both the effective chiral Lagrangian and the phenomenological hadronic
model. We further review the effects due to changes in their in-medium
properties on their collective flow in heavy ion collisions.

</DOC>
<DOC>
<DOCNO> 8902 </DOCNO>
Power Laws and Cities Population


  We study a few dynamical systems composed of many components whose sizes
evolve according to multiplicative stochastic rules. We compare them with
respect to the emergence of power laws in the size distribution of their
components. We show that the details specifying and enforcing the smallest size
of the components are crucial as well as the rules for creating new components.
In the systems where the power law holds, one obtains for the exponent alpha
the experimentally measured value 1 for a wide range of parameters.

</DOC>
<DOC>
<DOCNO> 120599 </DOCNO>
A Search for the Optical/Infrared Counterpart of the Anomalous X-ray


  We have carried out a search for the optical and infrared counterpart of the
Anomalous X-ray Pulsar 1E 1841-045, which is located at the center of the
supernova remnant Kes73. We present the first deep optical and infrared images
of the field of 1E 1841-045, as well as optical spectroscopy results that
exclude the brightest objects in the error circle as possible counterparts. A
few of the more reddened objects in this region can be considered as
particularly interesting candidates, in consideration of the distance and
absorption expected from the association with Kes73. The strong interstellar
absorption in the direction of the source does not allow to completely exclude
the presence of main sequence massive companions.

</DOC>
<DOC>
<DOCNO> 8834 </DOCNO>
Distribution function of the local density of states of a one-channel


  A real space diagrammatic method, which is an extension of the Berezinskii
technique to problems with periodic boundary condition, is formulated to study
the density of states (DOS) \rho(\epsilon,\phi) and its moments for a
one-channel weakly disordered ring threaded by an external magnetic flux \phi.
The exact result obtained for the average value of the DOS shows that
\rho(\epsilon,\phi) oscillates with a period of the flux quantum \phi_0=hc/e.
However all higher moments of the DOS oscillate with the halved period
\phi_0/2. The exact expression for the DOS is valid for both weak localization
(L >> l, where L is the rings circumference and l is the mean free path) and
ballistic (L < l) regimes. In the weak localization regime the distribution
function of the DOS is calculated, which turns out to be of logarithmic normal
form.

</DOC>
<DOC>
<DOCNO> 99847 </DOCNO>
A Hodge Theorem for noncompact manifolds


  The inclusion of the complex of coclosed harmonic forms on a connected
riemannian manifold into the complex of all forms induces a Frechet isomorphism
in cohomology.

</DOC>
<DOC>
<DOCNO> 102232 </DOCNO>
Splitting of Singularities


  We study one parameter deformations of a pair consisting of an analytic
singular space $X_0$ and a function $f_0$ on it, in case this defines an
isolated singularity. We prove, under general conditions, a bouquet
decomposition of the Milnor fibre when the isolated singularity splits in the
deformation and the invariance of the Milnor fibration if there is no
splitting.

</DOC>
<DOC>
<DOCNO> 67751 </DOCNO>
Bloch-Nordsieck violating electroweak corrections to inclusive TeV scale


  We point out that, since the colliders initial states (e+ e-,p p, p pbar, ...
) carry a definite nonabelian flavor, electroweak radiative corrections to
inclusive hard cross sections at the TeV scale are affected by peculiar
Bloch-Nordsieck violating double logs. We recall the setup of soft cancellation
theorems, and we analyze the magnitude of the noncancelling terms in the
example of electron - positron annihilation into hadrons.

</DOC>
<DOC>
<DOCNO> 39870 </DOCNO>
Extracting Matter Effects, Masses and Mixings at a Neutrino Factory


  We discuss and quantify different possibilities to determine matter effects,
the value and the sign of $Delta m^2_{31}$, as well as the magnitude of $\sin^2
2\theta_{13}$ in very long baseline neutrino oscillation experiments. We study
neutrino oscillation at a neutrino factory in the $\nu_\mu\to\nu_\mu$
disappearance and $\nu_e\to\nu_\mu$ appearance channels with and without muon
charge identification. One possibility is to analyze the $\nu_e\to\nu_\mu$
appearance channels leading to wrong sign muon events, which requires however
very good muon charge identification. Without charge identification it is still
possible to operate the neutrino factory both with $\mu^-$ and $\mu^+$ beams
and to analyze the differences in the total neutrino event rate spectra. We
show that this leads already to a quite good sensitivity, which may be
important if right sign charge rejection capabilities are insufficient. With
muon charge identification one can study the $\nu_\mu\to\nu_\mu$ disappearance
and the $\nu_e\to\nu_\mu$ appearance channels independently. The best method is
finally achieved by combining all available information of the
$\nu_\mu\to\nu_\mu$ disappearance and $\nu_e\to\nu_\mu$ appearance channels
with charge identification and we show the sensitivity which can be achieved.

</DOC>
<DOC>
<DOCNO> 150672 </DOCNO>
Brane World with Bulk Horizons


  A brane world in the presence of a bulk black hole is constructed. The brane
tension is fine tuned in terms of the black hole mass and cosmological
constant. Gravitational perturbations localized on the brane world are
discussed.

</DOC>
<DOC>
<DOCNO> 71083 </DOCNO>
Event-by-Event Fluctuations from Decay of a Polyakov Loop Condensate


  A model for particle production at the deconfining phase transition in QCD is
developed, as the semi-classical decay of a condensate for the Polyakov loop.
In such a model, generically particle production, as measured on an
event-by-event basis, exhibits significant deviations from statistical
behavior.

</DOC>
<DOC>
<DOCNO> 67993 </DOCNO>
Test of T violation in neutral B decays


  T violation should be tested independently of CP violation. Besides K system,
B meson decays provide another good place to study T violation. In the Standard
Model, T violation in $B^0 \rightleftharpoons \bar{B^0}$ oscillation is
expected to be small. The angular distribution of $B\to VV$ decay permits one
to extract the T-odd correlation. In the absence of final state interaction, T
violation in $B\to J/\psi(l^+ l^-) K^*(K_S\pi^0)$ decay can reach $4-7%$ via
$B^0-\bar{B^0}$ mixing.

</DOC>
<DOC>
<DOCNO> 116620 </DOCNO>
Low cloud properties influenced by cosmic rays


  The influence of solar variability on climate is currently uncertain. Recent
observations have indicated a possible mechanism via the influence of solar
modulated cosmic rays on global cloud cover. Surprisingly the influence of
solar variability is strongest in low clouds (<= 3km), which points to a
microphysical mechanism involving aerosol formation that is enhanced by
ionisation due to cosmic rays. If confirmed it suggests that the average state
of the Heliosphere is important for climate on Earth.

</DOC>
<DOC>
<DOCNO> 170047 </DOCNO>
Parametrization and distillability of three-qubit entanglement


  There is an ongoing effort to quantify entanglement of quantum pure states
for systems with more than two subsystems. We consider three approaches to this
problem for three-qubit states: choosing a basis which puts the state into a
standard form, enumerating ``local invariants,'' and using operational
quantities such as the number of maximally entangled states which can be
distilled. In this paper we evaluate a particular standard form, the {\it
Schmidt form}, which is a generalization of the Schmidt decomposition for
bipartite pure states. We show how the coefficients in this case can be
parametrized in terms of five physically meaningful local invariants; we use
this form to prove the efficacy of a particular distillation technique for GHZ
triplets; and we relate the yield of GHZs to classes of states with unusual
entanglement properties, showing that these states represent extremes of
distillability as functions of two local invariants.

</DOC>
<DOC>
<DOCNO> 84358 </DOCNO>
Gravitational waves from black hole collisions via an eclectic approach


  We present the first results in a new program intended to make the best use
of all available technologies to provide an effective understanding of waves
from inspiralling black hole binaries in time for imminent observations. In
particular, we address the problem of combining the close-limit approximation
describing ringing black holes and full numerical relativity, required for
essentially nonlinear interactions. We demonstrate the effectiveness of our
approach using general methods for a model problem, the head-on collision of
black holes. Our method allows a more direct physical understanding of these
collisions indicating clearly when non-linear methods are important. The
success of this method supports our expectation that this unified approach will
be able to provide astrophysically relevant results for black hole binaries in
time to assist gravitational wave observations.

</DOC>
<DOC>
<DOCNO> 100447 </DOCNO>
On Wlodarczyk's embedding theorem


  We prove the following version of Wlodarczyk's Embedding Theorem: Every
normal complex algebraic ${\bf C}^*$-variety admits an equivariant closed
embedding into a toric prevariety $X$ on which ${\bf C}^*$ acts as a
one-parameter-subgroup of the big torus of $X$.

</DOC>
<DOC>
<DOCNO> 120235 </DOCNO>
Time Lags in Low Mass X-ray Binaries


  Using RXTE/PCA data, we have studied the time lag (TL) properties of a sample
of four accreting neutron stars (NSs), namely 1E1724-3045, GS1826-238,
4U1705-44 and 4U1728-34. The aim of the study is to identify the spectral and
timing state(s) in which TLs are detected. Along this work, we have discovered
TLs between the 7-40 keV hard and 2-7 keV soft photons from 4U1728-34 with
amplitudes similar to those seen in 4U1705-44 (i.e. 2 ms at 5 Hz). We show that
the TLs are only seen in the low states of those sources, but that within the
so-called ``island'' spectral state, some sources display TLs whereas some do
not. On the other hand, we have found that TLs are detected when the associated
Power Density Spectrum (PDS) shows excess power at high frequencies (above 1
Hz).

</DOC>
<DOC>
<DOCNO> 67974 </DOCNO>
Lattice QCD Calculations of the Sigma Commutator


  As a direct source of information on chiral symmetry breaking within QCD, the
sigma commutator is of considerable importance. With recent advances in the
calculation of hadron masses within full QCD it is of interest to see whether
the sigma commutator can be calculated directly from the dependence of the
nucleon mass on the input quark mass. We show that provided the correct chiral
behaviour of QCD is respected in the extrapolation to realistic quark masses
one can indeed obtain a fairly reliable determination of the sigma commutator
using present lattice data. Within two-flavour, dynamical-fermion QCD the value
obtained lies in the range 45 to 55 MeV.

</DOC>
<DOC>
<DOCNO> 123297 </DOCNO>
Star Formation in Clusters: Subclustering, Cloud Fragmentation and the


  We review recent high spatial resolution millimeter continuum and spectral
line observations of (proto-)cluster regions. These observations reveal that
the mass distribution of prestellar cores is consistent with the initial mass
function for field stars suggesting that the IMF is connected to the molecular
clouds structure or the cloud fragmentation processes, rather than the details
of the star formation mechanism. We discuss the evidence for at-birth
subclustering independently obtained for two separate protoclusters. The
presence of subclustering within coherent subclumps suggests that the
fragmentation process is hierarchical and that young stellar clusters are
assembled by independent substructures. The local (proto-)stellar density and
star formation efficiency within the subclusters are much higher than the
average values for the entire star forming cloud. Unfortunately, current
observations are sparse and limited to the nearest star forming regions, for
spatial resolution and sensitivity considerations, the future millimeter wave
arrays, especially ALMA, will allow to expand considerably the sample of
observed regions.

</DOC>
<DOC>
<DOCNO> 70860 </DOCNO>
Photon and lepton pair production in a quark-gluon plasma


  We discuss the production of real or virtual photons in a quark-gluon plasma.

</DOC>
<DOC>
<DOCNO> 150394 </DOCNO>
D-Branes in Type IIA and Type IIB Theories from Tachyon Condensation


  In this paper we will construct all BPS and non-BPS D-branes in Type IIA and
Type IIB theories from tachyon condensation. We also propose form of
Wess-Zumino term for non-BPS D-brane and we will show that tachyon condensation
in this term leads to standard Wess-Zumino term for BPS D-brane.

</DOC>
<DOC>
<DOCNO> 8277 </DOCNO>
Inter-Landau-level skyrmions versus quasielectrons in the nu=2 quantum


  We consider the charged excitations in the quantum Hall effect with a large
Zeeman splitting at filling factor nu=2. When the Zeeman splitting is increased
over a critical value the groundstate undergoes a first order phase transition
from a paramagnetic to a ferromagnetic phase. We have studied the possibility
to form charged spin-textured excitations, "inter Landau level Skyrmions",
close to this transition and find that these never are the lowest lying charged
excitations but can under certain conditions provide an effective driving
mechanism for the paramagnetic to ferromagnetic phase transition. We show that
the charged excitations inevitably present in the system can act as nucleation
centers even at T=0 and hence set a specific limit for the maximal hysteresis
attainable in this case. Calculations of how the finite width of the
two-dimensional electron gas affects the nu=2 phase transition and the
polarization at higher filling factors are also presented.

</DOC>
<DOC>
<DOCNO> 39731 </DOCNO>
Q-balls in Underground Experiments


  In this paper we present some features of Q-balls and we discuss their
interactions with matter, and their energy losses in the Earth, for a large
range of velocities. These calculations are used to compute the fractional
geometrical acceptance of the MACRO detector. Furthermore a systematic analysis
of the energy losses of Q-balls in three types of detectors is investigated.
More specifically we have computed the light yield in liquid scintillators, the
ionization in streamer tubes and the Restricted Energy Loss in the CR39 nuclear
track detectors.

</DOC>
<DOC>
<DOCNO> 151451 </DOCNO>
Quantum Holonomies for Quantum Computing


  Holonomic Quantum Computation (HQC) is an all-geometrical approach to quantum
information processing. In the HQC strategy information is encoded in
degenerate eigen-spaces of a parametric family of Hamiltonians. The
computational network of unitary quantum gates is realized by driving
adiabatically the Hamiltonian parameters along loops in a control manifold. By
properly designing such loops the non-trivial curvature of the underlying
bundle geometry gives rise to unitary transformations i.e., holonomies that
implement the desired unitary transformations. Conditions necessary for
universal QC are stated in terms of the curvature associated to the non-abelian
gauge potential (connection) over the control manifold. In view of their
geometrical nature the holonomic gates are robust against several kind of
perturbations and imperfections. This fact along with the adiabatic fashion in
which gates are performed makes in principle HQC an appealing way towards
universal fault-tolerant QC.

</DOC>
<DOC>
<DOCNO> 121350 </DOCNO>
RXTE Investigation into Extended Hard X-ray Emission from Elliptical


  We present results of the first RXTE investigation of hard X-ray emission
from normal elliptical galaxies. Joint spectral analysis of RXTE PCA and ASCA
GIS data for NGC 4472 and NGC 4649 reveals the presence of about 5 10^-12 erg
cm^-2 s^-1 of 2-10 keV emission emanating from a region outside of the optical
galaxy, and of a spectral hardness intermediate between the galactic hot
interstellar gas and X-ray binary components. A large fraction of this emission
originates in the Virgo intracluster medium (ICM) and we present constraints on
the ICM temperature and metallicity in the vicinity of these two galaxies.
However, the diffuse flux is significantly greater than expected based on the
soft X-ray intensity measured with ROSAT, allowing for the possible presence of
an additional diffuse non-thermal component. We also derive new constraints on
the integrated X-ray binary emission from these two galaxies, and on the
presence of a nuclear flat-spectrum point source.

</DOC>
<DOC>
<DOCNO> 101736 </DOCNO>
Partial Ordering of Gauge Orbit Types for SU(n)-Gauge Theories


  The natural partial ordering of the orbit types of the action of the group of
local gauge transformations on the space of connections in space-time dimension
d<=4 is investigated. For that purpose, a description of orbit types in terms
of cohomology elements of space-time, derived earlier, is used. It is shown
that, on the level of these cohomology elements, the partial ordering relation
is characterized by a system of algebraic equations. Moreover, operations to
generate direct successors and direct predecessors are formulated. The latter
allow to successively reconstruct the set of orbit types, starting from the
principal type.

</DOC>
<DOC>
<DOCNO> 9672 </DOCNO>
One- and two-particle microrheology


  We study the dynamics of rigid spheres embedded in viscoelastic media and
address two questions of importance to microrheology. First we calculate the
complete response to an external force of a single bead in a homogeneous
elastic network viscously coupled to an incompressible fluid. From this
response function we find the frequency range where the standard assumptions of
microrheology are valid. Second we study fluctuations when embedded spheres
perturb the media around them and show that mutual fluctuations of two
separated spheres provide a more accurate determination of the complex shear
modulus than do the fluctuations of a single sphere.

</DOC>
<DOC>
<DOCNO> 10283 </DOCNO>
Frustrated trimer chain model and Cu3Cl6(H2O)2 2H8C4SO2 in a magnetic


  Recent magnetization and susceptibility measurements on Cu3Cl6(H2O)2 2H8C4SO2
by Ishii et.al. [J. Phys. Soc. Jpn. 69, 340 (2000)] have demonstrated the
existence of a spin gap. In order to explain the opening of a spin gap in this
copper-trimer system, Ishii et.al. have proposed a frustrated trimer chain
model. Since the exchange constants for this model have not yet been
determined, we develop a twelfth-order high-temperature series for the magnetic
susceptibility and fit it to the experimentally measured one. We find that some
of the coupling constants are likely to be ferromagnetic. The combination of
several arguments does not provide any evidence for a spin gap in the parameter
region with ferromagnetic coupling constants, but further results e.g. for the
magnetization process are in qualitative agreement with the experimental
observations.

</DOC>
<DOC>
<DOCNO> 71677 </DOCNO>
Natural Chaotic Inflation in Supergravity and Leptogenesis


  We comprehensively investigate a chaotic inflation model proposed recently in
the framework of supergravity. In this model, the form of K\"ahler potential is
determined by a symmetry, that is, the Nambu-Goldstone-like shift symmetry,
which guarantees the absence of the exponential factor in the potential for the
inflaton field. Though we need the introduction of small parameters, the
smallness of the parameters is justified also by symmetries. That is, the zero
limit of the small parameters recovers symmetries, which is natural in the 't
Hooft's sense. The leptogenesis scenario via the inflaton decay in this chaotic
inflation model is also discussed. We find that the lepton asymmetry enough to
explain the present baryon number density is produced for low reheating
temperatures avoiding the overproduction of gravitinos.

</DOC>
<DOC>
<DOCNO> 117339 </DOCNO>
Strongly coupled Coulomb and nuclear plasma in inner crusts of neutron


  Matter of subnuclear density in the inner crusts of neutron stars consists of
neutron-rich atomic nuclei immersed in strongly degenerate relativistic gas of
electrons and strongly nonideal liquid of neutrons. We give a brief account of
thermodynamic and kinetic properties of this matter which are greatly affected
by Coulomb and nuclear interactions (a companion paper on the outer envelopes
is astro-ph/0012316) and show how they can be studied from observations of
thermal radiation of young (age < 100 yr) neutron stars (for a discussion of
the latter possibility, see astro-ph/0012306).

</DOC>
<DOC>
<DOCNO> 40369 </DOCNO>
A study of bB production mechanisms in Pythia


  The influence of the Pt_hat cutoff on the production of bB events in Pythia
has been studied. Versions 5.75, 6.115 and 6.152 have been considered.

</DOC>
<DOC>
<DOCNO> 178425 </DOCNO>
Two-Body Correlations in Nuclear Systems


  Correlations in the nuclear wave-function beyond the mean-field or
Hartree-Fock approximation are very important to describe basic properties of
nuclear structure. Various approaches to account for such correlations are
described and compared to each other. This includes the hole-line expansion,
the coupled cluster or ``exponential S'' approach, the self-consistent
evaluation of Greens functions, variational approaches using correlated basis
functions and recent developments employing quantum Monte-Carlo techniques.
Details of these correlations are explored and their sensitivity to the
underlying nucleon-nucleon interaction. Special attention is paid to the
attempts to investigate these correlations in exclusive nucleon knock-out
experiments induced by electron scattering. Another important issue of nuclear
structure physics is the role of relativistic effects as contained in
phenomenological mean field models. The sensitivity of various nuclear
structure observables on these relativistic features are investigated. The
report includes the discussion of nuclear matter as well as finite nuclei.

</DOC>
<DOC>
<DOCNO> 100427 </DOCNO>
U(g)-finite locally analytic representations


  In this paper we continue the study of locally analytic representations of a
$p$-adic Lie group $G$ in vector spaces over a spherically complete
non-archimedean field $K$, building on the algebraic approach to such
representations introduced in our paper "Locally analytic distributions and
p-adic representation theory, with applications to GL_2." In that paper we
associated to a representation $V$ a module $M$ over the ring $D(G,K)$ of
locally analytic distributions on $G$ and described an admissibility condition
on $V$ in terms of algebraic properties of $M$.
  In this paper we determine the relationship between our admissibility
condition on locally analytic modules and the traditional admissibility of
Langlands theory. We then analyze the class of locally analytic representations
with the property that their associated modules are annihilated by an ideal of
finite codimension in the universal enveloping algebra of G, showing under some
hypotheses on G that they are sums of representations of the form $X\otimes Y$,
with X finite dimensional and Y smooth. The irreducible representations of this
type are obtained when X and Y are irreducible.
  We conclude by analyzing the reducible members of the locally analytic
principal series of $SL_2(\Qp)$.

</DOC>
<DOC>
<DOCNO> 70096 </DOCNO>
Observable interactions of quintessence with ordinary matter and


  For any realistic theory of quintessence that allows for a violation of the
equivalence principle (VEP), we study the experimental constraints on such
theories coming from ordinary matter as well as neutrinos. We discuss and
compare constraints from two basically different (extra) contributions to
differences of fermion masses: one is due to the vacuum expectation value (vev)
of quintessence, and the other is based on a quintessence-exchange graph at
finite temperature/density.

</DOC>
<DOC>
<DOCNO> 178962 </DOCNO>
Comparison of Transfer-to-Continuum and Eikonal Models of Projectile


  Spectroscopic properties of nuclei are accessible with projectile
fragmentation reactions, but approximations made in the reaction theory can
limit the accuracy of the determinations. We examine here two models that have
rather different approximations for the nucleon wave function, the target
interaction, and the treatment of the finite duration of the reaction. The
nucleon-target interaction is treated differently in the eikonal and the
transfer-to-continuum model, but the differences are more significant for light
targets. We propose a new parameterization with that in mind. We also propose a
new formula to calculate the amplitude that combines the better treatment of
the wave function in the eikonal model with the better treatment of the target
interaction in the transfer-to-continuum model.

</DOC>
<DOC>
<DOCNO> 71937 </DOCNO>
On neutrino family problem


  The experiment conducted at the Brookhaven AGS at 1962 [1] on the interaction
of high-energy neutrinos with matter is considered in literature the
observation of electron and muon types of neutrinos. After analysis of the
experiment we have concluded that the latter does not give direct evidence of
the neutrino family existence.

</DOC>
<DOC>
<DOCNO> 119280 </DOCNO>
Numerical Simulations in Cosmology III: Dark Matter Halos


  Properties of dark matter halos are reviewed. Taken from different
publications, we present results on (1) the mass and velocity functions, (2)
density and velocity profiles, and (3) concentration of halos. In the range of
radii r=(0.005-1)rvir the density profile for a quiet isolated halo is very
accurately approximated by a fit suggested by Moore etal (1997):
rho=1/x^1.5(1+x^1.5), where x=r/rs and rs is a characteristic radius. The fit
suggested by Navarro et al (1995) rho= 1/x(1+x)^2, also gives a very
satisfactory approximation with relative errors of about 10% for radii not
smaller than 1% of the virial radius. The mass function of z=0 halos with mass
below 10^{13}Msun/h is approximated by a power law with slope alpha =-1.85. The
slope increases with the redshift. The velocity function of halos with Vmax<
500km/s is also a power law with the slope beta= -3.8-4. The power-law extends
to halos at least down to 10km/s. It is also valid for halos inside larger
virialized halos. The concentration of halos depends on mass (more massive
halos are less concentrated) and environment, with isolated halos being less
concentrated than halos of the same mass inside clusters. Halos have intrinsic
scatter of concentration: at 1sigma level halos with the same mass have
Delta(log{c_vir})=0.18 or, equivalently, DeltaVmax/Vmax =0.12. Velocity
anisotropy for both subhalos and the dark matter is approximated by beta(r)
=0.15+2x/[x^2+4], where x is radius in units of the virial radius.

</DOC>
<DOC>
<DOCNO> 68330 </DOCNO>
Constraint from Lamb Shift and Anomalous Magnetic Moment on Radiatively


  We investigate the precisely measured anomalous magnetic moment and Lamb
shift as tests for the possible existence of the radiatively induced Lorentz
and CPT violation effects in quantum electrodynamics. To this end we calculate
the one-loop vacuum polarization tensor and vertex radiative correction in
dimensional reduction and on-shell renormalization scheme. We explicitly show
how the Lorentz and CPT violation sector affects the anomalous magnetic moment
and Lamb shift. Remarkably, we find infrared divergences coming from Lorentz
and CPT violating term that do not cancel in physical cross sections. This
result appears to place stringent constraints on the type of Lorentz/CPT
violating terms that can be added to the QED Lagrangian.

</DOC>
<DOC>
<DOCNO> 178437 </DOCNO>
A Model for the 3He(\vec d, p)4He Reaction at Intermediate Energies


  Polarization correlation coefficients have been measured atRIKEN for the \vec
3He(\vec d,p)4He reaction at intermediate energies. We propose a model for the
(\vec d, p) reaction mechanism using the pd elastic scattering amplitude which
is rigorously determined by a Faddeev calculation and using modern NN forces.
Our theoretical predictions for deuteron polarization observables A_y, A_{yy},
A_{xx} and A_{xz} at E_d=140, 200 and 270 MeV agree qualitatively in shape with
the experimental data for the reaction 3He(\vec d,p)4He.

</DOC>
<DOC>
<DOCNO> 85406 </DOCNO>
Impulsive spherical gravitational waves


  Penrose's identification with warp provides the general framework for
constructing the continuous form of impulsive gravitational wave metrics. We
present the 2-component spinor formalism for the derivation of the full family
of impulsive spherical gravitational wave metrics which brings out the power in
identification with warp and leads to the simplest derivation of exact
solutions. These solutions of the Einstein vacuum field equations are obtained
by cutting Minkowski space into two pieces along a null cone and re-identifying
them with warp which is given by an arbitrary non-linear holomorphic
transformation. Using 2-component spinor techniques we construct a new metric
describing an impulsive spherical gravitational wave where the vertex of the
null cone lies on a world-line with constant acceleration.

</DOC>
<DOC>
<DOCNO> 123006 </DOCNO>
Models of Rapidly Rotating Neutron Stars: Remnants of Accretion Induced


  Equilibrium models of differentially rotating nascent neutron stars are
constructed, which represent the result of the accretion induced collapse of
rapidly rotating white dwarfs. The models are built in a two-step procedure:
(1) a rapidly rotating pre-collapse white dwarf model is constructed; (2) a
stationary axisymmetric neutron star having the same total mass and angular
momentum distribution as the white dwarf is constructed. The resulting
collapsed objects consist of a high density central core of size roughly 20 km,
surrounded by a massive accretion torus extending over 1000 km from the
rotation axis. The ratio of the rotational kinetic energy to the gravitational
potential energy of these neutron stars ranges from 0.13 to 0.26, suggesting
that some of these objects may have a non-axisymmetric dynamical instability
that could emit a significant amount of gravitational radiation.

</DOC>
<DOC>
<DOCNO> 100609 </DOCNO>
A note on extended complex manifolds


  We introduce a category of extended complex manifolds, and prove that the
functor describing deformations of a classical compact complex manifold $M$
within this category is versally representable by (an analytic subspace in)
$H^*(M,T_M)$. By restricting the associated versal family of extended complex
manifolds over $H^*(M,T_M)$ to the subspace $H^1(M,T_M)$ one gets a correct
limit to the classical picture.

</DOC>
<DOC>
<DOCNO> 117786 </DOCNO>
Do statistically significant correlations exist between the Homestake


  It has been suggested by various authors that a significant anticorrelation
exists between the Homestake solar neutrino data and the sunspot cycle. Some of
these claims rest on smoothing the data by taking running averages, a method
that has recently undergone criticism. We demonstrate that no significant
anticorrelation can be found in the Homestake, data, or in standard 2- and
4-point averages of that data. However, when 3-, 5-, and 7-point running
averages are taken, an anticorrelation seems to emerge whose significance grows
as the number of points in the average increases. Our analysis indicates that
the apparently high significance of these anticorrelations is an artifact of
the failure to consider the loss of independence introduced in the running
average process. When this is considered, the significance is reduced to that
of the unaveraged data. Furthermore, when evaluated via parametric subsampling,
no statistically significant anticorrelation is found. We conclude that the
Homestake data can not be used to substantiate any claim of an anticorrelation
with the sunspot cycle.

</DOC>
<DOC>
<DOCNO> 10300 </DOCNO>
Dynamical Linked Cluster Expansions for Spin Glasses


  Dynamical linked cluster expansions are linked cluster expansions with
hopping parameter terms endowed with their own dynamics. This amounts to a
generalization from 2-point to point-link-point interactions. An associated
graph theory with a generalized notion of connectivity is reviewed. We discuss
physical applications to disordered systems, in particular to spin glasses,
such as the bond-diluted Ising model and the Sherrington-Kirkpatrick spin
glass. We derive the rules and identify the full set of graphs that contribute
to the series in the quenched case. This way it becomes possible to avoid the
vague extrapolation from positive integer n to n=0, that usually goes along
with an application of the replica trick.

</DOC>
<DOC>
<DOCNO> 12311 </DOCNO>
Low energy phonon spectrum and its parameterization in pure KTaO3 under


  High resolution data on low energy phonon branches (acoustic and soft optic)
along the three principal symmetry axes in pure KTaO3 were obtained by cold
neutron inelastic scattering between 10 and 80 K. Additional off-principal axis
measurements were performed to characterize the dispersion anisotropy (away
from the <100> and <110> axes). The parameters of the phenomenological model
proposed by Vaks are refined in order to successfully describe the experimental
low temperature (10 < T < 100 K) dispersion curves, over an appreciable
reciprocal space volume around the zone center (|q| < 0.25 rlu). The refined
model, which involves only 4 temperature-independent adjustable parameters, is
intended to serve as a basis for quantitative computations of multiphonon
processes.

</DOC>
<DOC>
<DOCNO> 11746 </DOCNO>
Mesoscopic scattering in the half-plane: squeezing conductance through a


  We model the 2-probe conductance of a quantum point contact (QPC), in linear
response. If the QPC is highly non-adiabatic or near to scatterers in the open
reservoir regions, then the usual distinction between leads and reservoirs
breaks down and a technique based on scattering theory in the full
two-dimensional half-plane is more appropriate. Therefore we relate conductance
to the transmission cross section for incident plane waves. This is equivalent
to the usual Landauer formula using a radial partial-wave basis. We derive the
result that an arbitrarily small (tunneling) QPC can reach a p-wave channel
conductance of 2e^2/h when coupled to a suitable reflector. If two or more
resonances coincide the total conductance can even exceed this. This relates to
recent mesoscopic experiments in open geometries. We also discuss reciprocity
of conductance, and the possibility of its breakdown in a proposed QPC for atom
waves.

</DOC>
<DOC>
<DOCNO> 123139 </DOCNO>
Recent results from the Tokyo axion helioscope experiment


  We have searched for axions which could have been produced in the solar core
using an axion helioscope with a 2.3m-long 4T superconducting magnet. Axion
mass region up to m_a=0.26eV was newly explored by introducing
dispersion-matching gas. Preliminary analysis sets a limit on axion-photon
coupling constant to be less than (6.4--9.6)e-10 GeV^{-1} (95%CL) for this mass
region from the absence of the axion signal. This is more stringent than the
limit inferred from the solar age consideration and also more stringent than
the recent helioseismological bound.

</DOC>
<DOC>
<DOCNO> 151241 </DOCNO>
Spectral geometry of spacetime


  Spacetime, understood as a globally hyperbolic manifold, may be characterized
by spectral data using a 3+1 splitting into space and time, a description of
space by spectral triples and by employing causal relationships, as proposed
earlier. Here, it is proposed to use the Hadamard condition of quantum field
theory as a smoothness principle.

</DOC>
<DOC>
<DOCNO> 119512 </DOCNO>
The contribution of Narrow-Line Seyfert 1 galaxies to the soft X-ray


  The ROSAT Ultradeep HRI survey in the Lockman Hole contains a complete sample
of 91 X-ray sources with fluxes in the 0.5-2 keV band larger than 1.2 times
10e-15 erg cm-2 s-1, where over about 75 per cent of the sources are quasars or
Seyfert galaxies. During the course of our optical identification work, we have
obtained optical spectra of 67 narrow emission line galaxies (NELG), which are
physically not associated with the X-ray sources. We have derived the
equivalent width (EW) and the full width at half maximum (FWHM) for the most
prominent emission lines of 41 quasars and Seyfert galaxies taken from the
ROSAT Deep Survey (RDS), which has a flux limit of 5.5 times 10e-15 erg cm-2
s-1 in the 0.5-2.0 keV band. Furthermore we have obtained the EW and FWHM
values of the field NELGs. Here we present the spectroscopic discrimination
between RDS Seyfert galaxies and field galaxies (NELG). The analysis of the
emission lines has revealed that a single object out of 69 spectroscopically
identified AGN fits the optical criteria of Narrow-Line Seyfert 1 galaxies
(NLS1). This may indicate that NLS1 contribute only marginally to the soft
X-ray background, but we can not exclude a possible larger contribution.

</DOC>
<DOC>
<DOCNO> 102122 </DOCNO>
On the linearity of certain mapping class groups


  S. Bigelow proved that the braid groups are linear. That is, there is a
faithful representation of the braid group into the general linear group of
some field. Using this, we deduce from previously known results that the
mapping class group of a sphere with punctures and hyperelliptic mapping class
groups are linear. In particular, the mapping class group of a closed
orientable surface of genus 2 is linear.

</DOC>
<DOC>
<DOCNO> 122407 </DOCNO>
Simulation of a Space-Based Microlensing Survey for Terrestrial


  We show that a space-based gravitational microlensing survey for terrestrial
extra-solar planets is feasible in the near future, and could provide a nearly
complete picture of the properties of planetary systems in our Galaxy. We
present simulations of such a survey using a 1-2m aperture space telescope with
a ~2 square degree field-of-view which is used to continuously monitor ~10^8
Galactic bulge main sequence stars. The microlensing techniques allows the
discovery of low mass planets with high signal-to-noise, and the space mission
that we have studied are sensitive to planets with masses as low as that of
Mars. By targeting main sequence source stars, which can only be resolved from
space, the space-based microlensing survey is able to detect enough light from
the lens stars to determine the spectral type of one third of the lens stars
with detected planets, including virtually all of the F, G, and K stars which
comprise one quarter of the event sample. This enables the determination of the
planetary masses and separations in physical units, as well as the abundance of
planets as a function of stellar type and distance from the Galactic center. We
show that a space-based microlensing planet search program has its highest
sensitivity to planets at orbital separations of 0.7-10 AU, but it will also
have significant sensitivity at larger separations and will be able to detect
free-floating planets in significant numbers. This complements the planned
terrestrial planet transit missions which are sensitive to terrestrial planets
at separations of =< 1 AU. Such a mission also detect ~50,000 giant planets via
transits, and it is, therefore, the only proposed planet detection method that
is sensitive to planets at all orbital radii.

</DOC>
<DOC>
<DOCNO> 121588 </DOCNO>
The Magnetic Field Geometry in M82 and Cen A


  Imaging polarimetry at 1.65 and 2.2 $\mu $m is presented for the classic
starburst galaxy M82 and the advanced merger system Cen A. Polarimetry at near
IR wavelengths allows the magnetic field geometry in galaxies to be probed much
deeper into dusty regions than optical polarimetry. In M82, the magnetic field
throughout the nucleus has a polar geometry, presumably due to the massive
vertical flow that is a result of the intense star formation there. Fully two
thirds of the line of sight dust through to the center of M82 contains a
vertical magnetic field. In Cen A, the prominent dust lane shows a normal
planar field geometry. There is no indication of significant disturbance in the
field geometry in the dust lane and the polarization strength is near normal
for the amount of extinction. Either the magnetic field geometry was well
maintained during the merger, or it reestablished itself very easily.

</DOC>
<DOC>
<DOCNO> 71435 </DOCNO>
Cosmology and Hierarchy in Stabilized Randall-Sundrum Models


  We consider the cosmology and hierarchy of scales in models with branes
immersed in a five-dimensional curved spacetime subject to radion
stabilization. The universe naturally find itself in the radiation-dominated
epoch when the inter-brane spacing is static and stable, independent of the
form of the stabilizing potential. We recover the standard Friedmann equations
without assuming a specific form for the bulk energy-momentum tensor. We
address the hierarchy problem in the context of a quartic and exponential
stabilizing potential, and find that in either case the presence of a negative
tension brane is required and that the string scale can be as low as the
electroweak scale. In the situation of self-tuning branes (corresponding to an
exponential potential) where the bulk cosmological constant is set to zero, the
brane tensions have hierarchical values.

</DOC>
<DOC>
<DOCNO> 13352 </DOCNO>
Critical exponents of ferromagnetic Ising model on fractal lattices


  We review the value of the critical exponents $\nu^{-1}$, $\beta/\nu$, and
$\gamma/\nu$ of ferromagnetic Ising model on fractal lattices of Hausdorff
dimension between one and three. They are obtained by Monte Carlo simulation
with the help of Wolff algorithm. The results are accurate enough to show that
the hyperscaling law $d_f=2\beta/\nu+\gamma/\nu$ is satisfied in non-integer
dimension. Nevertheless, the discrepancy between the simulation results and the
$\epsilon$-expansion studies suggests that the strong universality should be
adapted for the fractal lattices.

</DOC>
<DOC>
<DOCNO> 119875 </DOCNO>
On the radial density profile of intracluster gas tracing the isothermal


  The cusped NFW universal density profile suggested by typical CDM models has
been challenged in recent years by the discoveries of the soft cores for a
broad range of masses from dwarf galaxies to clusters of galaxies. It is thus
desirable that a new, analytic model would instead become available for
virialized dark halos. One promising candidate is probably the empirical
density profile proposed by Burkert, which resembles an isothermal profile with
a constant core in the inner region and matches the NFW profile at large radii.
Meanwhile, such a revised dark halo (RDH) profile has turned out a great
success on galactic scales. This stimulates us to apply the RDH profile to more
massive systems like clusters of galaxies. In this paper we have made an
attempt to derive the radial density profile of intracluster gas from the RDH
profile, and compare it with those revealed by X-ray observations and inferred
from the NFW profile. It is shown that the RDH predicted gas density can be
well represented by the conventional beta model with a typical beta parameter
of 0.7-0.9. Fitting the theoretically predicted X-ray surface brightness
profile to an ensemble of 45 X-ray clusters, we find that the RDH and NFW
profiles become to be almost indistinguishable. Yet, the RDH profile allows us
to work out straightforwardly the central dark matter density of clusters from
X-ray measurements. Using the 45 clusters, we find that the central densities
of clusters have an average value of ~0.01 solar mass pc^{-3}, in agreement
with the result estimated on galactic scales, which reinforces the claim for
the presence of the soft halo cores over the entire mass range.

</DOC>
<DOC>
<DOCNO> 102643 </DOCNO>
Deux caracterisations de la mesure d'equilibre d'un endomorphisme de


  Let $\mu$ be the equilibrium measure of an endomorphism of ${\sf P}^k({\bf
C})$. We show that it is its unique measure of maximal entropy. We build $\mu$
directly as the distribution of any point outside an algebraic exceptional set.

</DOC>
<DOC>
<DOCNO> 178452 </DOCNO>
Polarization phenomena in the reaction NN to NNpi near threshold


  First calculations for spin-dependent observables of the reactions $pp \to
pp\pi^0$, $pp \to pn\pi^+$ and $pp \to d\pi^+$ near threshold are presented,
employing the J\"ulich model for pion production. The influence of resonant
(via the excitation of the $\Delta (1232)$) and non-resonant p-wave pion
production mechanisms on these observables is examined. For the reactions $pp
\to pn\pi^+$ and $pp \to d\pi^+$ nice agreement of our predictions with the
presently available data on spin correlation coefficents is observed whereas
for $pp \to pp\pi^0$ the description of the data is less satisfying.

</DOC>
<DOC>
<DOCNO> 119782 </DOCNO>
The Detection of Wind Variability in Magellanic Cloud O Stars


  We present Far Ultraviolet Explorer (FUSE) spectra for three Magellanic Cloud
O stars (Sk 80, Sk -67 05 and Sk -67 111) with repeated observations. The data
demonstrate the capabilities of FUSE to perform time-resolved spectroscopy on
extragalactic stars. The wavelength coverage of FUSE provides access to
resonance lines due to less abundant species, such as sulfur, which are
unsaturated in O supergiants. This allows us to examine wind variability at all
velocities in resonance lines for stars with higher mass loss rates than can be
studied at longer (lambda > 1150 A) wavelengths. The FUSE wavelength range also
includes resonance lines from ions which bracket the expected dominant
ionization stage of the wind. Our observations span 1-4 months with several
densely sampled intervals of 10 hours or more. These observations reveal wind
variability in all of the program stars and distinctive differences in the
ionization structure and time scales of the variability. Sk -67 111
demonstrates significant wind variability on a time scale less than 10 hours
and the coolest O star (Sk -67 05) exhibits the largest variations in O VI.

</DOC>
<DOC>
<DOCNO> 9582 </DOCNO>
Pearling Instabilities of Membrane Tubes with Anchored Polymers


  We have studied the pearling instability induced on hollow tubular lipid
vesicles by hydrophilic polymers with hydrophobic side groups along the
backbone. The results show that the polymer concentration is coupled to local
membrane curvature. The relaxation of a pearled tube is characterized by two
different well-separated time scales, indicating two physical mechanisms. We
present a model, which explains the observed phenomena and predicts polymer
segregation according to local membrane curvature at late stages.

</DOC>
<DOC>
<DOCNO> 68453 </DOCNO>
The Evolution of the MLLA Parton Spectra


  The evolution with energy scale of the partonic logarithmic scaled energy
spectra is investigated in the framework of the modified leading logarithmic
approximation (MLLA). The behaviour of the higher order moments is compared to
a number of analytic predictions and $\rm e^+e^-$ data.

</DOC>
<DOC>
<DOCNO> 102610 </DOCNO>
Fields with pseudo-exponentiation


  We study the structure of an algebraically closed field with extra function
resembling the classical exponentiation on complex numbers.

</DOC>
<DOC>
<DOCNO> 116861 </DOCNO>
An injector for the CLIC test Facility (CTF3)


  The CLIC Test Facility (CTF3) is an intermediate step to demonstrate the
technical feasibility of the key concepts of the new RF power source for CLIC.
CTF3 will use electron beams with an energy range adjustable from 170 MeV (3.5
A) to 380 MeV (with low current). The injector is based on a thermionic gun
followed by a classical bunching system embedded in a long solenoidal field. As
an alternative, an RF photo-injector is also being studied. The beam dynamics
studies on how to reach the stringent beam parameters at the exit of the
injector are presented. Simulations performed with the EGUN code showed that a
current of 7 A can be obtained with an emittance less than 10 mm.mrad at the
gun exit. PARMELA results are presented and compared to the requested beam
performance at the injector exit. Sub-Harmonic Bunchers (SHB) are foreseen, to
switch the phase of the bunch trains by 180 degrees from even to odd RF
buckets. Specific issues of the thermionic gun and of the SHB with fast phase
switch are discussed.

</DOC>
<DOC>
<DOCNO> 116321 </DOCNO>
Formalizing the gene centered view of evolution


  A historical dispute in the conceptual underpinnings of evolution is the
validity of the gene centered view of evolution. \cite{dawkins,lewontin} We
transcend this debate by formalizing the gene centered view as a dynamic
version of the mean field approximation. This establishes the conditions under
which it is applicable and when it is not. In particular, it breaks down for
trait divergence which corresponds to symmetry breaking in evolving
populations.

</DOC>
<DOC>
<DOCNO> 10207 </DOCNO>
Interlayer c-axis transport in the normal state of cuprates


  A theoretical model of c-axis transport properties in cuprates is proposed.
Inter-plane and in-plane charge fluctuations make hopping between planes
incoherent and diffusive (the in-plane momentum is not conserved after
tunneling). The non-Drude optical conductivity $\sigma_c(\omega)$ and the
power-law temperature dependence of the {\it dc} conductivity are generically
explained by the strong fluctuations excited in the process of tunneling.
Several microscopic models of the charge fluctuation spectrum are considered.

</DOC>
<DOC>
<DOCNO> 84295 </DOCNO>
Shell sources as a probe of relativistic effects in neutron star models


  A perturbing shell is introduced as a device for studying the excitation of
fluid motions in relativistic stellar models. We show that this approach allows
a reasonably clean separation of radiation from the shell and from fluid
motions in the star, and provides broad flexibility in the location and
timescale of perturbations driving the fluid motions. With this model we
compare the relativistic and Newtonian results for the generation of even
parity gravitational waves from constant density models. Our results suggest
that relativistic effects will not be important in computations of the
gravitational emission except possibly in the case of excitation of the neutron
star on very short time scales.

</DOC>
<DOC>
<DOCNO> 99920 </DOCNO>
The intersection of spheres in a sphere and a new geometric meaning of


  Let S^3_i be a 3-sphere embedded in the 5-sphere S^5 (i=1,2). Let S^3_1 and
S^3_2 intersect transversely. Then the intersection C of S^3_1 and S^3_2 is a
disjoint collection of circles. Thus we obtain a pair of 1-links, C in S^3_i
(i=1,2), and a pair of 3-knots, S^3_i in S^5 (i=1,2). Conversely let (L_1,L_2)
be a pair of 1-links and (X_1,X_2) be a pair of 3-knots. It is natural to ask
whether the pair of 1-links (L_1,L_2) is obtained as the intersection of the
3-knots X_1 and X_2 as above. We give a complete answer to this question. Our
answer gives a new geometric meaning of the Arf invariant of 1-links.
  Let f be a smooth transverse immersion S^3 into S^5. Then the
self-intersection C consists of double points. Suppose that C is a single
circle in S^5. Then f^{-1}(C) in S^3 is a 1-knot or a 2-component 1-link. There
is a similar realization problem. We give a complete answer to this question.

</DOC>
<DOC>
<DOCNO> 122034 </DOCNO>
Mining the Digital Hamburg/ESO Objective Prism Survey


  We report on the exploitation of the stellar content of the Hamburg/ESO
objective prism survey by quantitative selection methods, such as automatic
spectral classification, and first results obtained.

</DOC>
<DOC>
<DOCNO> 100966 </DOCNO>
A Perturbative SU(3) Casson Invariant


  A perturbative SU(3) Casson invariant $\Lambda_{SU(3)}(X)$ for integral
homology 3-spheres is defined. Besides being fully perturbative, it has nice
properties: (1) $4 . \Lambda_{SU(3)}(X)$ is an integer. (2) It is preseved
under orientation change. (3) A connected sum formula holds.
  Explicit calculations of the invariant for $1/k$ surgery on $(2,q)$ torus
knots are made and compared with a different generalization of Casson's
invariant to SU(3) by Boden and Herald. For those cases computed, the invariant
defined here is a quadratic polynomial in k for k>0 and a quadratic polynomial
for k<0.

</DOC>
<DOC>
<DOCNO> 80971 </DOCNO>
SU(2) lattice gauge theory at non-zero temperature with fixed holonomy


  We study SU(2) lattice gauge theory at $T>0$ in a finite box with fixed
holonomy value at the spatial boundary. We search for (approximate) classical
solutions of the lattice field equations and find in particular the dissociated
calorons recently discussed by van Baal and collaborators.

</DOC>
<DOC>
<DOCNO> 170801 </DOCNO>
Beyond Unruh Effect: Nonequilibrium Quantum Dynamics of Moving Charges


  We discuss some common misconceptions in Unruh effect and Unruh radiation for
the cases of linear and circular uniform acceleration of a charged particle or
detector moving in a quantum field. We point to the need to go beyond Unruh
effect and develop a new theoretical framework for treating the stochastic
dynamics of particles interacting with quantum fields under more general
nonequilibrium conditions. This framework has been established in recent years
using the influence functional formalism and applied to relativistically moving
charged particles. Only with nonequilibrium concepts and methodology applied to
particle-field interaction can one grasp the full complexity of the problems of
beam physics under more realistic conditions, from electrons and heavy ions to
coherent atoms.

</DOC>
<DOC>
<DOCNO> 169993 </DOCNO>
Quantum Amplitude Amplification and Estimation


  Consider a Boolean function $\chi: X \to \{0,1\}$ that partitions set $X$
between its good and bad elements, where $x$ is good if $\chi(x)=1$ and bad
otherwise. Consider also a quantum algorithm $\mathcal A$ such that $A \ket{0}
= \sum_{x\in X} \alpha_x \ket{x}$ is a quantum superposition of the elements of
$X$, and let $a$ denote the probability that a good element is produced if $A
\ket{0}$ is measured. If we repeat the process of running $A$, measuring the
output, and using $\chi$ to check the validity of the result, we shall expect
to repeat $1/a$ times on the average before a solution is found. *Amplitude
amplification* is a process that allows to find a good $x$ after an expected
number of applications of $A$ and its inverse which is proportional to
$1/\sqrt{a}$, assuming algorithm $A$ makes no measurements. This is a
generalization of Grover's searching algorithm in which $A$ was restricted to
producing an equal superposition of all members of $X$ and we had a promise
that a single $x$ existed such that $\chi(x)=1$. Our algorithm works whether or
not the value of $a$ is known ahead of time. In case the value of $a$ is known,
we can find a good $x$ after a number of applications of $A$ and its inverse
which is proportional to $1/\sqrt{a}$ even in the worst case. We show that this
quadratic speedup can also be obtained for a large family of search problems
for which good classical heuristics exist. Finally, as our main result, we
combine ideas from Grover's and Shor's quantum algorithms to perform amplitude
estimation, a process that allows to estimate the value of $a$. We apply
amplitude estimation to the problem of *approximate counting*, in which we wish
to estimate the number of $x\in X$ such that $\chi(x)=1$. We obtain optimal
quantum algorithms in a variety of settings.

</DOC>
<DOC>
<DOCNO> 68865 </DOCNO>
Top quark pair production near the threshold in e+e- collisions


  It was reported that the NNLO correction to the total cross section near the
ttbar threshold in e+e- collisions is as large as the NLO correction to it. In
the thesis, we improve the convergence of the perturbative series of the total
cross section by choosing appropriate expansion parameters for both m_t and
alpha_s. With these two prescriptions, the perturbative convergence is much
improved. Correspondingly, the resulting ambiguity for the determination of m_t
is estimated to be 0.1GeV.
  We also study the effect of all types of anomalous top-quark EDM interactions
near the threshold for the first time. We show that one can disentangle these
EDMs by the dependence of CP-odd observables on the CM-energy and on the degree
of initial state polarization. The sensitivity to chromo-EDM at LC turns out to
be better than that at LC in the open top region, but to be worse than that at
LHC by a factor 1/10. The sensitivities to electroweak-EDMs near the threshold
are similar to those in the open top region at LC.

</DOC>
<DOC>
<DOCNO> 13752 </DOCNO>
Full counting statistics of electron transfer between superconductors


  We present an extension of the Keldysh-Green's function method, which allows
to calculate the full distribution of transmitted particles through a
mesoscopic superconductor. The method is applied to the statistics of
supercurrent in short contacts. If the current is carried by Andreev bound
states the distribution corresponds to switching between long trains of
electrons going in opposite directions. For weak (gapless) superconductors or
tunnel junctions we find that at low temperatures the distribution has negative
`probabilities'. Accounting for the quantum mechanical nature of the measuring
device shows that these negative values can indeed be measured.

</DOC>
<DOC>
<DOCNO> 8602 </DOCNO>
Adsorbed and Grafted Polymers at Equilibrium


  This chapter deals with various aspects related to the adsorption of long
chain-like macromolecules (polymers) onto solid surfaces. Physical aspects of
the adsorption mechanism are elaborated mainly at thermodynamical equilibrium.
The basic features needed in modeling of this adsorption are discussed. We
first discuss the adsorption of a single and long polymer chain to the surface.
The surface interaction is modeled by a potential well with a long-ranged
attractive tail. A simple mean-field theory description is presented and the
concept of polymer "blobs" is used to describe the conformation of the chain at
the surface. The thickness of the adsorbed layer depends on several polymer and
surface parameters. Fluctuation corrections to mean-field theory are also
discussed. We then review adsorption as well as depletion processes in the
many-chain case. Profiles, changes in the surface tension and polymer surface
excess are calculated within mean-field theory. Corrections due to fluctuations
in good solvent are taken into account using scaling concepts. The proximal
exponent is introduced in analogy to surface critical phenomena. The
interaction between two surfaces with adsorbed polymer layers is discussed, and
various cases leading to attractive and repulsive interactions are mentioned.
Polyelectrolytes are of practical importance due to their water solubility; we
give a short summary of recent progress in this rapidly evolving field. The
behavior of grafted polymers, i.e., polymers which are anchored with one end to
a solid substrate is also reviewed.

</DOC>
<DOC>
<DOCNO> 10017 </DOCNO>
The effects of interactions and disorder in the two-dimensional chiral


  We study the two-dimensional chiral metal, which is formed at the surface of
a layered three-dimensional system exhibiting the integer quantum Hall effect
by hybridization of the edge states associated with each layer of the sample.
We investigate mesoscopic fluctuations, dynamical screening and inelastic
scattering in the chiral metal, focussing particularly on fluctuations of
conductance, $\delta g(B)$, with magnetic field, $B$. The correlation function
$<\delta g(B) \delta g(B+\delta B)>$ provides information on the inelastic
scattering rate, $\tau_{in}^{-1}$, through both the variance of fluctuations
and the range of correlations in $\delta B$. We calculate this correlation
function for samples which are not fully phase coherent. Two regimes of
behaviour exist, according to whether $\tau_{in}^{-1}$ is smaller or larger
than $\tau_{\perp}^{-1}$, the rate for inter-edge tunneling, and we give
results in both regimes. We also investigate dynamical screening of Coulomb
interactions in the chiral metal and calculate the contribution to
$\tau_{in}^{-1}$ from electron-electron scattering, finding $\tau_{in}^{-1}
\propto T^{3/2}$ for $\tau_{in}^{-1} \ll \tau_{\perp}^{-1}$ at temperature $T$.

</DOC>
<DOC>
<DOCNO> 122184 </DOCNO>
Self-Interacting Dark Matter with Flavor Mixing


  The crisis of both cold and collisional dark matter (DM) models is resolved
by postulating flavor mixing of DM particles. Flavor-mixed particles segregate
in the gravitational field to form dark halos composed of heavy mass
eigenstates. Since these particles are mixed in the interaction basis, elastic
collisions convert some of heavy eigenstates into light ones which leave the
halo. This annihilation-like process will soften dense central cusps of halos.
The proposed model accumulates most of the attractive features of
self-interacting and annihilating DM models, but does not suffer from their
severe drawbacks. This model is natural does not require fine tuning.

</DOC>
<DOC>
<DOCNO> 12777 </DOCNO>
Magnetic Field Induced Low-Energy Spin Excitations in YBa2Cu4O8 Measured


  We have measured the spin susceptibility of the underdoped high temperature
superconductor, YBa2Cu4O8 by Gd^{3+} electron spin resonance in single crystals
and aligned powders at several magnetic fields between 3 and 15.4 T. At low
temperatures and high fields, the spin susceptibility of the CuO2 planes is
enhanced slightly in the $B\parallel c$ orientation with respect to the $B\perp
c$ orientation. The enhancement in an applied field of 15.4 T ($\approx 0.15
H_{c2}$) at 16 K (0.2 $T_c$) is approximately 10 percent of the susceptibility
measured at $T_c$. Such a small magnitude suggests that the second critical
field of superconductivity, $H_{c2}\approx 100 T$, would not suppress the
pseudogap. This work demonstrates the potential of high field ESR in single
crystals for studying high $T_c$ superconductors.

</DOC>
<DOC>
<DOCNO> 83166 </DOCNO>
MOO: A Methodology for Online Optimization through Mining the Offline


  Ports, warehouses and courier services have to decide online how an arriving
task is to be served in order that cost is minimized (or profit maximized).
These operators have a wealth of historical data on task assignments; can these
data be mined for knowledge or rules that can help the decision-making?
  MOO is a novel application of data mining to online optimization. The idea is
to mine (logged) expert decisions or the offline optimum for rules that can be
used for online decisions. It requires little knowledge about the task
distribution and cost structure, and is applicable to a wide range of problems.
  This paper presents a feasibility study of the methodology for the well-known
k-server problem. Experiments with synthetic data show that optimization can be
recast as classification of the optimum decisions; the resulting heuristic can
achieve the optimum for strong request patterns, consistently outperforms other
heuristics for weak patterns, and is robust despite changes in cost model.

</DOC>
<DOC>
<DOCNO> 71009 </DOCNO>
Proton Decay, Black Holes, and Large Extra Dimensions


  We consider proton decay in theories that contain large extra dimensions. If
virtual black hole states are allowed by the theory, as is generally the case,
then proton decay can proceed via virtual black holes. The experimental limits
on the proton lifetime place strong constraints on the quantum gravity scale
$\mnew$ (the effective Planck mass). For most theories, our constraint implies
a lower bound of $\mnew > 10^{16}$ GeV. The corresponding bound on the size of
large extra dimensions is $\ell < 10^{6/n} \times 10^{-30}$ cm, where $n$ is
the number of such dimensions. Regrettably, for most theories this limit rules
out the possibility of observing large extra dimensions at accelerators or in
millimeter scale gravity experiments. Conversely, proton decay could be
dominated by virtual black holes, providing an experimental probe to study
stringy quantum gravity physics.

</DOC>
<DOC>
<DOCNO> 70162 </DOCNO>
Nonperturbative Calculation of Scattering Amplitudes


  A method for the nonperturbative calculation of scattering amplitudes and
cross sections is discussed in the context of light-cone quantization. The
Lanczos-based recursion method of Haydock is suggested for the computation of
matrix elements of the resolvent for the light-cone Hamiltonian, from which the
T-matrix can be constructed. The scattering of composite particles is handled
by a generalization of a formulation given by Wick.

</DOC>
<DOC>
<DOCNO> 119036 </DOCNO>
Sub-TeV Gammas in Coincidence with BATSE Gamma Ray Bursts


  We report on results of a search for high-energy gamma-ray-induced muon
secondaries in coincidence with gamma ray bursts (GRBs) detected by BATSE. If a
gamma ray of 1 TeV energy arrives in coincidence with a GRB, its pion
production and decay leads to ~0.23 muons with sufficient energy to reach
detection level. Such muons have been identified and their angles measured
using the Project GRAND air shower array. A total of six bright bursts have
been identified from the BATSE GRB catalog which occurred near zenith while
Project GRAND was in operation. Of these six, the GRB with the highest product
of GRB flux and geometrical acceptance shows evidence of an enhanced muon count
rate at the burst time and angle at the +3.2 sigma level. The chance
probability of obtaining our results for these six GRBs is 5E-4. Simple
extrapolations of the low-energy BATSE gamma-ray energy spectra for these GRBs
to the energy region of GRAND are unable to explain the observed muon count
rates. Thus the observed excesses suggest a new component of higher energy
gamma rays associated with these bursts.

</DOC>
<DOC>
<DOCNO> 120797 </DOCNO>
HST Spectroscopy of Spot 1 on the Circumstellar Ring of SN 1987A


  We present ultraviolet and optical spectra of the first bright spot (PA = 29
degrees) on Supernova 1987A's equatorial circumstellar ring taken with the
Space Telescope Imaging Spectrograph. We interpret this spot as the emission
produced by radiative shocks that occur where the supernova blast wave strikes
an inward protrusion of the ring. The observed line widths and intensity ratios
indicate the presence of radiative shocks with velocities ranging from 100 to
250 km s^-1 entering dense (> 10^4 cm^-3) gas. These observations, and future
observations of the development of the spectra and line profiles, provide a
unique opportunity to study the hydrodynamics of radiative shocks.

</DOC>
<DOC>
<DOCNO> 117029 </DOCNO>
Compactification of the moduli space in symplectization and hidden


  In this paper, we establish the compactification of the moduli space in
symplectization and and studied the hidden symmetries of its boundary.

</DOC>
<DOC>
<DOCNO> 122175 </DOCNO>
Long-term evolution of a dipole type magnetosphere interacting with an


  The evolution of an initially stellar dipole type magnetosphere interacting
with an accretion disk is investigated numerically using the ideal MHD ZEUS-3D
code in the 2D-axisymmetry option. The simulations last several thousands of
Keplerian periods of the inner disk. A Keplerian disk is assumed as a boundary
condition prescribing a mass inflow into the corona. Additionally, a stellar
wind from a rotating central star is prescribed. Our major result is that the
initially dipole type field develops into a spherically radial outflow pattern
with two main components, a disk wind and a stellar wind component. These
components evolve into a quasi- stationary final state. The poloidal field
lines follow a conical distribution. As a consequence of the initial dipole,
the field direction in the stellar wind is opposite to that in the disk wind.
The maximum speed of the outflow is about the Keplerian speed at the inner disk
radius. With the chosen mass flow rates and field strength we see almost no
indication for a flow self-collimation.

</DOC>
<DOC>
<DOCNO> 84341 </DOCNO>
Spherically symmetric self-similar solutions and their astrophysical and


  We discuss spherically symmetric perfect fluid solutions of Einstein's
equations which have equation of state ($p=\alpha \mu$) and which are
self-similar in the sense that all dimensionless variables depend only upon
$z\equiv r/t$. For each value of $\alpha$, such solutions are described by two
parameters and have now been completely classified. There is a 1-parameter
family of solutions asymptotic to the flat Friedmann model at large values of
z. These represent either black holes or density perturbations which grow as
fast as the particle horizon; the underdense solutions may be relevant to the
existence of large-scale cosmic voids. There is also a 1-parameter family of
solutions asymptotic to a self-similar Kantowski-Sachs model at large z. These
are probably only physically realistic for $-1<\alpha<-1/3$, in which case they
may relate to the formation of bubbles in an inflationary universe. There is a
2-parameter family of solutions associated with a self-similar static solution
at large z. This family contains solutions with naked singularities and this
includes the ``critical'' solution discovered in recent collapse calculations
for $\alpha < 0.28$. Finally, for $\alpha >1/5$, there is a family of solutions
which are asymptotically Minkowski. These asymptote either to infinite z, in
which case they are described by one parameter, or to a finite value of z, in
which case they are described by two parameters and this includes the
``critical'' solution for $\alpha >0.28$. We discuss the stability of
spherically symmetric similarity solutions to more general (non-self-similar)
spherically symmetric perturbations.

</DOC>
<DOC>
<DOCNO> 150318 </DOCNO>
The String Uncertainty Relations follow from the New Relativity


  The String Uncertainty Relations have been known for some time as the stringy
corrections to the original Heisenberg's Uncertainty principle. In this letter
the Stringy Uncertainty relations, and corrections thereof, are explicitly
derived from the New Relativity Principle that treats all dimensions and
signatures on the same footing and which is based on the postulate that the
Planck scale is the minimal length in Nature in the same vein that the speed of
light was taken as the maximum velocity in Einstein's theory of Special
Relativity. The Regge behaviour of the string's spectrum is also a natural
consequence of this New Relativity Principle.

</DOC>
<DOC>
<DOCNO> 67818 </DOCNO>
Flavor Changing Effects in Theories with a Heavy Z' Boson with Family


  There are theoretical and phenomenological motivations that there may exist
additional heavy Z' bosons with family non-universal couplings. Flavor mixing
in the quark and lepton sectors will then lead to flavor changing couplings of
the heavy Z', and also of the ordinary Z when Z-Z' mixing is included. The
general formalism of such effects is described, and applications are made to a
variety of flavor changing and CP-violating tree and loop processes. Results
are described for three specific cases motivated by a specific heterotic string
model and by phenomenological considerations, including cases in which all
three families have different couplings, and those in which the first two
families, but not the third, have the same couplings. Even within a specific
theory the results are model dependent because of unknown quark and lepton
mixing matrices. However, assuming that typical mixings are comparable to the
CKM matrix, processes such as coherent mu-e conversion in a muonic atom,
K^0-\Bar{K}^0 and B-\Bar{B} mixing, epsilon, and epsilon'/epsilon lead to
significant constraints on Z' bosons in the theoretically and
phenomenologically motivated range M_{Z'} \sim 1 TeV.

</DOC>
<DOC>
<DOCNO> 170635 </DOCNO>
NMR implementation of a building block for scalable quantum computation


  We report the implementation of the central building block of the
Schulman-Vazirani procedure for fully polarizing a subset of two-level quantum
systems which are initially only partially polarized. This procedure consists
of a sequence of unitary operations and incurs only a quasi-linear overhead in
the number of quantum systems and operations required. The key building block
involves three quantum systems and was implemented on a homonuclear three-spin
system using room temperature liquid state nuclear magnetic resonance (NMR)
techniques. This work was inspired by the state initialization challenges in
current NMR quantum computers but also shines new light on polarization
transfer in NMR.

</DOC>
<DOC>
<DOCNO> 9678 </DOCNO>
Impurity scattering effects on the low-temperature specific heat of


  Very recently impurity scattering effects on quasiparticles in d-wave
superconductors have attracted much attention. Especially, the thermodynamic
properties in magnetic fields H are of interest. We have measured the
low-temperature specific heat C(T,H) of La_1.78Sr_0.22Cu_1-xNi_xO4. For the
first time, the impurity scattering effects on C(T,H) of cuprate
superconductors were clearly observed, and are compared with theory of d-wave
superconductivity. It is found that impurity scattering leads to
gamma(H)=gamma(0)(1+D((H/H_c2)(ln(H_c2/H)) in small magnetic fields. Most
amazingly, the scaling of C(T,H) breaks down due to impurity scattering.

</DOC>
<DOC>
<DOCNO> 11459 </DOCNO>
Frequency dependent specific heat of viscous silica


  We apply the Mori-Zwanzig projection operator formalism to obtain an
expression for the frequency dependent specific heat c(z) of a liquid. By using
an exact transformation formula due to Lebowitz et al., we derive a relation
between c(z) and K(t), the autocorrelation function of temperature fluctuations
in the microcanonical ensemble. This connection thus allows to determine c(z)
from computer simulations in equilibrium, i.e. without an external
perturbation. By considering the generalization of K(t) to finite wave-vectors,
we derive an expression to determine the thermal conductivity \lambda from such
simulations. We present the results of extensive computer simulations in which
we use the derived relations to determine c(z) over eight decades in frequency,
as well as \lambda. The system investigated is a simple but realistic model for
amorphous silica. We find that at high frequencies the real part of c(z) has
the value of an ideal gas. c'(\omega) increases quickly at those frequencies
which correspond to the vibrational excitations of the system. At low
temperatures c'(\omega) shows a second step. The frequency at which this step
is observed is comparable to the one at which the \alpha-relaxation peak is
observed in the intermediate scattering function. Also the temperature
dependence of the location of this second step is the same as the one of the
$\alpha-$peak, thus showing that these quantities are intimately connected to
each other. From c'(\omega) we estimate the temperature dependence of the
vibrational and configurational part of the specific heat. We find that the
static value of c(z) as well as \lambda are in good agreement with experimental
data.

</DOC>
<DOC>
<DOCNO> 178681 </DOCNO>
Relevant polarization observables for the study of the Roper resonance


  The purpose of this contribution is to stress the great importance of
polarization observables for the study of nucleon resonances, in particular in
the case of deuteron and proton probes. Polarization observables play a unique
role in signing the reaction mechanism and bring new information in the
microscopic description of baryon resonances. We will calculate the relevant
polarization observables, for $p+d$- and $p+\alpha$-collisions, in case of
inclusive reactions and for some selected exclusive channels.

</DOC>
<DOC>
<DOCNO> 118937 </DOCNO>
Limits on radio emission from pulsar wind nebulae


  We report on a sensitive survey for radio pulsar wind nebulae (PWN) towards
27 energetic and/or high velocity pulsars. Observations were carried out at 1.4
GHz using the Very Large Array and the Australia Telescope Compact Array, and
utilised pulsar-gating to search for off-pulse emission. These observing
parameters resulted in a considerably more sensitive search than previous
surveys, and could detect PWN over a much wider range of spatial scales (and
hence ambient densities and pulsar velocities). However, no emission clearly
corresponding to a PWN was discovered. Based on these non-detections we argue
that the young and energetic pulsars in our sample have winds typical of young
pulsars, but produce unobservable PWN because they reside in low density (n
approx 0.003 cm^-3) regions of the ISM. However, non-detections of PWN around
older and less energetic pulsars can only be explained if the radio luminosity
of their winds is less than 1e-5 of their spin-down luminosity, implying an
efficiency at least an order of magnitude smaller than that seen for young
pulsars.

</DOC>
<DOC>
<DOCNO> 150333 </DOCNO>
Conformal anomaly of (2,0) tensor multiplet in six dimensions and


  We compute the conformal anomaly of free d=6 superconformal (2,0) tensor
multiplet on generic curved background. Up to a trivial covariant
total-derivative term, it is given by the sum of the type A part proportional
to the 6-d Euler density, and the type B part containing three independent Weyl
invariants. Multiplied by factor 4N^3, the type B part of the anomaly
reproduces exactly the corresponding part of the conformal anomaly of large N
multiple M5-brane (2,0) theory as predicted (hep-th/9806087) by the AdS/CFT
correspondence. The coefficients of the type A anomaly differ by the factor 4/7
x 4 N^3, so that the free tensor multiplet anomaly does not vanish on a
Ricci-flat background. The coefficient 4N^3 is the same as found
(hep-th/9703040) in the comparison of the tensor multiplet theory and the d=11
supergravity results for the absorption cross-sections of gravitons by M5
branes, and in the comparison (hep-th/9911135) of 2- and 3-point stress tensor
correlators of the free tensor multiplet with the AdS_7 supergravity
predictions. The reason for this coincidence is that the three Weyl-invariant
terms in the anomaly are related to the $h^2$ and $h^3$ terms in the near flat
space expansion of the corresponding non-local effective action, and thus to
the 2-point and 3-point stress tensor correlators in flat background. At the
same time, the type A anomaly is related to the $h^4$ term in the non-local
part of the effective action, i.e. to a certain structure in the 4-point
correlation function of stress tensors.

</DOC>
<DOC>
<DOCNO> 119516 </DOCNO>
ISOPHOT Observations of Narrow-Line Seyfert 1 Galaxies


  Broad infrared spectra (7-200 micrometer) of four NLS1 galaxies, obtained
with the imaging photo-polarimeter (ISOPHOT) on board the Infrared Space
Observatory (ISO), are presented. The infrared luminosities and temperatures,
opacities and sizes of the emitting dust components are derived. A comparison
between the observed infrared spectra and the optical emission line fluxes of a
sample of 16 NLS1 galaxies suggests that these objects suffer different degrees
of dust absorption according to the inclination of the line of sight with
respect to the dust distribution.

</DOC>
<DOC>
<DOCNO> 11565 </DOCNO>
Features of Hopping Integral and Unconventional Orbital Modes for


  We use the coherent state approximation for the skyrmion in the isotropic
quantum Heisenberg ferromagnet to obtain analytical expression for skyrmion
hopping integral as a function of distance. It appears the skyrmion hopping is
restricted by distances larger than its effective diameter. Some puzzling
properties of the orbital skyrmionic modes are discussed. Spin distribution in
these states is obtained and effect of quantum spin contraction is
demonstrated.The principal possibility of lowering the skyrmion energy due to a
bonding-like state formation is illustrated.

</DOC>
<DOC>
<DOCNO> 13062 </DOCNO>
General Formula for the Magnetoresistance on the Basis of the Fermi


  The general expression for the magnetoresistance (MR) due to the Lorentz
force is derived by using the Fermi liquid transport theory based on the Kubo
formula. The obtained gauge-invariant expression is exact for any strength of
the interaction, as for the most singular term with respect to 1/\gamma^\ast
(\gammak^\ast being the quasiparticle damping rate). By virtue of the
exactness, the conserving laws are satisfied rigorously in the present
expression, which is indispensable for avoiding unphysical solutions. Based on
the derived expression, we can calculate the MR within the framework of the
Baym-Kadanoff type conserving approximation, by including all the vertex
corrections required by the Ward identity. The present expression is
significant especially for strongly correlated systems because the current
vertex corrections will be much important. On the other hand, if we drop all
the vertex corrections in the formula, we get the MR of the relaxation time
approximation (RTA), which is commonly used because of the simplicity. However,
the RTA is dangerous because it may give unphysical results owing to the lack
of conserving laws. In conclusion, the present work enables us to study the MR
with satisfying the conserving laws which is highly demanded in strongly
correlated electrons, such as high-Tc superconductors, organic metals, and
heavy Fermion systems. In Appendix D, we reply to the comment by O. Narikiyo
[cond-mat/0006028]. (Note that Appendix D exists only in the e-preprint
version.)

</DOC>
<DOC>
<DOCNO> 99404 </DOCNO>
Convergence of Bieberbach polynomials in domains with interior cusps


  We extend the results on the uniform convergence of Bieberbach polynomials to
domains with certain interior zero angles (outward pointing cusps), and show
that they play a special role in the problem. Namely, we construct a
Keldysh-type example on the divergence of Bieberbach polynomials at an outward
pointing cusp and discuss the critical order of tangency at this interior zero
angle, separating the convergent behavior of Bieberbach polynomials from the
divergent one for sufficiently thin cusps.

</DOC>
<DOC>
<DOCNO> 101541 </DOCNO>
Spin Calogero-Moser systems associated with simple Lie algebras


  We introduce spin Calogero-Moser systems associated with root systems of
simple Lie algebras and give the associated Lax representations (with spectral
parameter) and fundamental Poisson bracket relations. Our analysis is based on
a group-theoretic framework similar in spirit to the standard classical
$r$-matrix theory for constant $r$-matrices.

</DOC>
<DOC>
<DOCNO> 118565 </DOCNO>
Does the unification of BL Lac and FR I radio galaxies require jet


  We explore the viability of the unification of BL Lacs and FR I radio
galaxies by comparing the core emission of radio galaxies with those of BL Lacs
of similar extended radio power, taking advantage of the newly measured optical
nuclear luminosity of FR I sources. The spectral properties of complete samples
are also studied in the radio-optical luminosity plane: starting from the
Spectral Energy Distribution (SED) of BL Lacs, we calculate the predicted
luminosity of FR I nuclei in the frame of a simple one--zone model, by properly
taking into account the relativistic transformations. We find that the bulk
Lorentz factors required by the spread in the observed luminosities in all
bands are significantly smaller than those implied by other, both observational
and theoretical, considerations. This discrepancy is also reflected in the fact
that FR I nuclei are over-luminous by a factor of 10-10^4, with respect to the
predictions, both in the radio and in the optical band.
  In order to reconcile these results with the unification scheme, velocity
structures in the jet are suggested, where a fast spine is surrounded by a slow
(but still relativistic) layer so that the emission at different angles is
dominated by different velocity components: the fast one dominates the emission
in BL Lacs while the slow layer dominates the emission in misaligned objects.
Furthermore for the lowest luminosity BL Lacs it has to be also postulated that
their beaming factor in the radio band is lower than in the optical (and
X-ray), as would result from deceleration of the jet.
  The self-consistency of the unification model therefore requires that both
intrinsic differences in the SED and different beaming properties play a
substantial role in characterizing the phenomenology of these sources.

</DOC>
<DOC>
<DOCNO> 83045 </DOCNO>
Structured Language Modeling for Speech Recognition


  A new language model for speech recognition is presented. The model develops
hidden hierarchical syntactic-like structure incrementally and uses it to
extract meaningful information from the word history, thus complementing the
locality of currently used trigram models. The structured language model (SLM)
and its performance in a two-pass speech recognizer --- lattice decoding ---
are presented. Experiments on the WSJ corpus show an improvement in both
perplexity (PPL) and word error rate (WER) over conventional trigram models.

</DOC>
<DOC>
<DOCNO> 117487 </DOCNO>
A Definitive Optical Detection of a Supercluster at z = 0.91


  We present the results from a multi-band optical imaging program which has
definitively confirmed the existence of a supercluster at z = 0.91. Two massive
clusters of galaxies, CL1604+4304 at z = 0.897 and CL1604+4321 at z = 0.924,
were originally observed in the high-redshift cluster survey of Oke, Postman &
Lubin (1998). They are separated by 4300 km/s in radial velocity and 17
arcminutes on the plane of the sky. Their physical and redshift proximity
suggested a promising supercluster candidate. Deep BRi imaging of the region
between the two clusters indicates a large population of red galaxies. This
population forms a tight, red sequence in the color--magnitude diagram at (R-i)
= 1.4. The characteristic color is identical to that of the
spectroscopically-confirmed early-type galaxies in the two member clusters. The
red galaxies are spread throughout the 5 Mpc region between CL1604+4304 and
CL1604+4321. Their spatial distribution delineates the entire large scale
structure with high concentrations at the cluster centers. In addition, we
detect a significant overdensity of red galaxies directly between CL1604+4304
and CL1604+4321 which is the signature of a third, rich cluster associated with
this system. The strong sequence of red galaxies and their spatial distribution
clearly indicate that we have discovered a supercluster at z = 0.91.

</DOC>
<DOC>
<DOCNO> 72087 </DOCNO>
Weakly Warped Extra Dimensions and SN1987A


  The neutrino pulse from SN1987A provides one of the most rigourous
constraints on models of extra dimensions. Previously, calculations have been
done to bound the size of these extra dimensions in the case when the metric
was factorizable. Here we consider the case of 2 `weakly warped' extra
dimensions. We find that even though weak warping seems only to affect the zero
mode this can have a measurable effect on the supernovae bounds. In any
braneworld model such warping is necessarily present and as such should be
taken into account in supernovae bounds and in searches for corrections to
Newtonian gravity.

</DOC>
<DOC>
<DOCNO> 9095 </DOCNO>
Quarter-filled spin density wave states with long-range Coulomb


  Spin density wave (SDW) states at quarter-filling, which coexist with charge
density wave (CDW) states, have been examined where the critical temperature is
calculated for an extended Hubbard model with long range repulsive
interactions. Within the mean-field theory, it is shown that the first order
transition occurs with decreasing temperature for interactions located around
the boundary between SDW state and CDW state.

</DOC>
<DOC>
<DOCNO> 119856 </DOCNO>
The radial distribution of OB star formation in the Galaxy


  We present the azimuthally averaged radial distribution of 748 regions of OB
star formation in the whole galactic disk, based on our previous CS(2-1) survey
of UC H II regions. Embedded massive stars produce a total FIR luminosity of
1.39E8 Lsun within the range 0.2<R/Ro<2 in galactocentric radius. We find 492
massive star forming regions within the solar circle, producing 81% of the
total FIR luminosity. Separate analyses of the 349 sources in the I and II
quadrant (north), and of the 399 sources in the III and IV quadrant (south),
yield FIR luminosities (extrapolated to the complete galactic disk) of 1.17E8
Lsun and of 1.60E8 Lsun, respectively. Massive star formation is distributed in
a layer with its centroid Zo(R) following that of molecular gas for all
galactocentric radii, both north and south. Its thickness for R<Ro is ~73 pc
(FWHM), 62% the thickness of the molecular gas disk. The FIR luminosity
produced by massive stars has a well defined maximum at R=0.55Ro, with a
gaussian FWHM of 0.28Ro - compared with 0.51Ro for the H2 surface density
distribution. Toward the outer Galaxy, down from the maximum, the face-on FIR
surface luminosity decays exponentially with a scale length of 0.21Ro, compared
with 0.34Ro for the H2 surface density. Massive star formation per unit H2 mass
is maximum for R~0.55Ro in the southern Galaxy, with a FIR surface luminosity
to H2 surface density ratio of 0.41Lsun/Msun, compared with 0.21Lsun/Msun at
the same radius in the north, and with an average of ~0.18Lsun/Msun for the
whole galactic disk within the solar circle.

</DOC>
<DOC>
<DOCNO> 9355 </DOCNO>
Analysis of the Metallic Phase of Two-Dimensional Holes in SiGe in Terms


  We find that temperature dependent screening can quantitatively explain the
metallic behaviour of the resistivity on the metallic side of the so-called
metal-insulator transition in p-SiGe. Interference and interaction effects
exhibit the usual insulating behaviour which is expected to overpower the
metallic background at sufficiently low temperatures. We find empirically that
the concept of a Fermi-liquid describes our data in spite of the large r_s = 8.

</DOC>
<DOC>
<DOCNO> 68202 </DOCNO>
Pseudo-Dirac Solar Neutrinos


  Three of the viable solutions of the solar neutrino problem are consistent
with close to maximal leptonic mixing:
$\sin^2\theta_{12}={1\over2}(1-\epsilon_{12})$ with $|\epsilon_{12}|\ll1$.
Flavor models can naturally explain close to maximal mixing if approximate
horizontal symmetries force a pseudo-Dirac structure on the neutrino mass
matrix. An experimental determination of $|\epsilon_{12}|$ and
sign($\epsilon_{12}$) can constrain the structure of the lepton mass matrices
and consequently provide stringent tests of such flavor models. If both
$|\epsilon_{12}|$ and $\Delta m^2_{21}$ are known, it may be possible to
estimate the mass scale of the pseudo-Dirac neutrinos. Radiative corrections to
close to maximal mixing are negligible. Subtleties related to the kinetic terms
in Froggatt-Nielsen models are clarified.

</DOC>
<DOC>
<DOCNO> 118204 </DOCNO>
Age and metallicity gradients in the Galactic Bulge - A differential


  The Galactic Bulge has long been assumed to be a largely old stellar
population. However, some recent studies based on observations with the HST
WF/PC-1 and WFPC2 of stars in the Galactic Bulge have concluded that the old
population may not make up more then 30% of the total. Other studies using
HST/WFPC2 differential studies of `Bulge' globular clusters and field stars
have found the bulge to be comparable in age to the Galactic Halo. A
complication in all these studies is the presence of a substantial population
of stars which mimic a young bulge population, but which may be, and are often
assumed to be, foreground disk stars whose reddening and distance distributions
happen to mimic a young bulge turnoff. We show, using number counts in
HST/WFPC2 colour-magnitude diagrams of both field stars in the Bulge and of two
`bulge' and one `disk' globular cluster (NGC6528, NGC6553, and NGC5927) that
the stars interpreted as young in fact are foreground disk stars. Thus, we
confirm that the bulk of the bulge field stars in Baade's Window are old. The
existence of a young metal-rich population cannot, however, be ruled out from
our data. We also test for age and metallicity gradients using the CMD of a
metal-rich globular cluster as an empirical isochrone and derive a metallicity
difference of <0.2 dex between Baade's window and SGR-I window.

</DOC>
<DOC>
<DOCNO> 151259 </DOCNO>
Asymmetric Orientifolds, Brane Supersymmetry Breaking and Non-BPS Branes


  A new class of six-dimensional asymmetric orientifolds is considered where
the orientifold operation is combined with T-duality. The models are
supersymmetric in the bulk, but the cancellation of the tadpoles requires the
introduction of brane configurations that break supersymmetry. These can be
described by D7-brane anti-brane pairs, non-BPS D8-branes or D9-brane
anti-brane pairs. The transition between these different configurations and
their stability is analysed in detail.

</DOC>
<DOC>
<DOCNO> 13999 </DOCNO>
What can superconductivity learn from quantized vorticity in He-3


  In He-3 superfluids quantized vorticity can take many different forms: It can
appear as distributed periodic textures, as sheets, or as lines. In the
anisotropic He-3A phase in most cases the amplitude of the order parameter
remains constant throughout the vortex structure and only its orientation
changes in space. In the quasi-isotropic He-3B phase vortex lines have a hard
core where the order parameter has reduced, but finite amplitude. The different
structures have been firmly identified, based on both measurement and
calculation. What parallels can be drawn from this information to the new
unconventional superconductors or Bose-Einstein condensates?

</DOC>
<DOC>
<DOCNO> 152461 </DOCNO>
Supergravity and D-branes Wrapping Supersymmetric 3-Cycles


  We construct dual supergravity descriptions of D3-branes wrapping associative
3-cycles $L$. We analyse the conditions for having five-dimensional background
solutions of the form $AdS_2 \times L$ and show that they require $L$ to be of
constant negative curvature type. This provides $AdS_2$ background solutions
when $L$ is the hyperbolic space $H^3$ or its quotients by subgroups of its
isometry group. We construct a regular numerical solution interpolating between
$AdS_5$ in the UV and $AdS_2 \times H^3$ in the IR. The IR fixed point exists
at the ``intersection'' of the Coulomb and Higgs branches. We analyse the
singular supergravity solutions which correspond to moving into the Higgs and
the Coulomb branches. For negative constant curvature spaces the singularity is
of a ``good'' type in the Higgs branch and of a ``bad'' type in the Coulomb
branch. For positive constant curvature spaces such as $S^3$ the singularity is
of a ``bad'' type in both the Higgs and the Coulomb branches. We discuss the
meaning of these results.

</DOC>
<DOC>
<DOCNO> 80840 </DOCNO>
Four-quark operators in hadrons


  We present calculations of matrix elements of 4-quark operators in the pion
and in the nucleon extracted from quenched Monte Carlo simulations at beta =
6.0 using Wilson fermions. These operators are relevant for higher-twist
effects. We are particularly careful to avoid mixing with lower-dimensional
operators by choosing appropriate flavour structures.

</DOC>
<DOC>
<DOCNO> 101461 </DOCNO>
A continued fraction expansion for a q-tangent function


  We prove a continued fraction expansion for a certain q--tangent function
that was conjectured by Prodinger.

</DOC>
<DOC>
<DOCNO> 13093 </DOCNO>
The heat capacity of the restricted primitive model electrolyte


  The constant-volume heat capacity, C_V(T, rho), of the restricted primitive
model (RPM) electrolyte is considered in the vicinity of its critical point. It
is demonstrated that, despite claims, recent simulations for finite systems do
not convincingly indicate the absence of a divergence in C_V(T, rho)--which
would point to non-Ising-type criticality. The strong qualitative difference
between C_V for the RPM and for a Lennard-Jones fluid is shown to result from
the low critical density of the former. If one considers the theoretically
preferable configurational heat-capacity density, C_V/V, the finite-size
results for the two systems display qualitatively similar behavior on
near-critical isotherms.

</DOC>
<DOC>
<DOCNO> 40160 </DOCNO>
The KARMEN Time Anomaly: Search for a Neutral Particle of Mass 33.9 MeV


  We have searched for the pion decay pi^+ --> mu^+ X, where X is a neutral
particle of mass 33.905 MeV. This process was suggested by the KARMEN
Collaboration to explain an anomaly in their observed time distribution of
neutrino induced reactions. Having measured the muon momentum spectrum of
charged pions decaying in flight, we find no evidence for this process and
place an upper limit on the branching fraction eta leq 6.0 * 10^{-10} of such a
decay at a 95% confidence level.

</DOC>
<DOC>
<DOCNO> 70454 </DOCNO>
Progress in Perturbative Color Transparency


  A brief overview of the status of color transparency experiments is
presented. We report on the first complete calculations of color transparency
within a perturbative QCD framework. We also comment on the underlying
factorization method and assumptions. Detailed calculations show that the slope
of the transparency ratio with $Q^2$, and the effective attenuation cross
sections extracted from color transparency experiments depend on the $x$
distribuition of wave functions.

</DOC>
<DOC>
<DOCNO> 72213 </DOCNO>
Experimental implications of the dual colour solution to the generation


  Apart from offering explanations not only for the distinctive fermion mass
and mixing patterns but also for the actual values of the mass and mixing
parameters, the dual colour solution to the generation puzzle gives numerous
detailed predictions ranging from rare FCNC meson decays and $\mu$-$e$
conversions in nuclei at low energies to cosmic ray air showers with energies
beyond $10^{20}$ eV at the extreme end of the experimental range. Besides, it
predicts a new class of flavour-violating phenomena (called transmutations) due
to the rotating fermion mass matrix which are unambiguously calculable.
Comparison with experiment of these many ``parameter-free'' predictions reveals
no violation of existing bounds but identifies several striking effects which
can be tested with present experimental sensitivity.

</DOC>
<DOC>
<DOCNO> 101117 </DOCNO>
SU(3) Clebsch-Gordan Coefficients


  The paper contains the derivation of a general set of recurrence formulas for
the calculus of the SU(3) Clebsch-Gordan coefficients. The first six sections
are introductory, presenting the notations and placing SU(3) in the framework
of the general group theory. The following eight sections are devoted to the
detailed treatment of the carrier spaces of the irreducible representations and
their direct product.

</DOC>
<DOC>
<DOCNO> 118036 </DOCNO>
Some statistical properties of spiral galaxies


  This paper presents some statistical correlations of 72 northern spiral
galaxies. The results show that early-type spirals that are brighter, and
thicker, and the axis ratios ($H_{z}/H_r$) of the disk tend to be smaller along
the Hubble sequence. We also find that $H_{z}/H_r$ correlates strongly with the
galaxy's color, and early-type spirals have larger values of $H_{z}/H_r$. The
inclinations obtained by fitting the pattern of a spiral structure with a
logarithmic spiral form are nearly the same as those obtained by using the
formulas of Aaronson et al. (1980). Finally, the mean measured pitch angles for
the different Hubble sequences in the Third Catalogue of Bright Galaxies by de
Vaucouleurs et al. (1991) are derived.

</DOC>
<DOC>
<DOCNO> 123305 </DOCNO>
Oscillations During Thermonuclear X-ray Bursts


  High amplitude, nearly coherent X-ray brightness oscillations during
thermonuclear X-ray bursts were discovered with the Rossi X-ray Timing Explorer
(RXTE) in early 1996. Spectral and timing evidence strongly supports the
conclusion that these oscillations are caused by rotational modulation of the
burst emission and that they reveal the spin frequency of neutron stars in low
mass X-ray binaries, a long sought goal of X-ray astronomy. Studies carried out
over the past year have led to the discovery of burst oscillations in four new
sources, bringing to ten the number with confirmed burst oscillations. I review
the status of our knowledge of these oscillations and indicate how they can be
used to probe the physics of neutron stars. For a few burst oscillation sources
it has been proposed that the strongest and most ubiquitous frequency is
actually the first overtone of the spin frequency and hence that two nearly
antipodal hot spots are present on the neutron star. This inference has
important implications for both the physics of thermonuclear burning as well as
the mass - radius relation for neutron stars, so its confirmation is crucial. I
discuss recent attempts to confirm this hypothesis for 4U 1636-53, the source
for which a signal at the putative fundamental (290 Hz) has been claimed.

</DOC>
<DOC>
<DOCNO> 117605 </DOCNO>
VSL theories and the Doppler peak


  We discuss constraints on so-called `varying speed of light theories' coming
from the physics of the early universe. Specifically, we consider the position
of the first acoustic peak of the CMB angular power spectrum, showing that the
recent determination of its position by various CMB experiments, in particular
BOOMERanG/NA, can be used to constrain the value of the speed of light $c$
after the epoch of last scattering. Specifically, we find that for a flat
universe and a standard density of baryonic matter a variation in $c$ of up to
4% is consistent with the current observations. The position of the Doppler
peak is fairly sensitive to changes in $c$, and future observations should
dramatically improve this bound. On the other hand, we also find that the
maximum baryonic density allowed in VSL theories is about $\Omega_B h^2\sim
0.06\Omega_0$. We comment on the significance of these results.

</DOC>
<DOC>
<DOCNO> 83436 </DOCNO>
Lattice Structure and Convergence of a Game of Cards


  This paper is devoted to the study of the dynamics of a discrete system
related to some self stabilizing protocol on a ring of processors.

</DOC>
<DOC>
<DOCNO> 117292 </DOCNO>
Finite time singularities in a class of hydrodynamic models


  Models of inviscid incompressible fluid are considered, with the kinetic
energy (i.e., the Lagrangian functional) taking the form ${\cal L}\sim\int
k^\alpha|{\bf v_k}|^2d^3{\bf k}$ in 3D Fourier representation, where $\alpha$
is a constant, $0<\alpha< 1$. Unlike the case $\alpha=0$ (the usual Eulerian
hydrodynamics), a finite value of $\alpha$ results in a finite energy for a
singular, frozen-in vortex filament. This property allows us to study the
dynamics of such filaments without the necessity of a regularization procedure
for short length scales. The linear analysis of small symmetrical deviations
from a stationary solution is performed for a pair of anti-parallel vortex
filaments and an analog of the Crow instability is found at small wave-numbers.
A local approximate Hamiltonian is obtained for the nonlinear long-scale
dynamics of this system. Self-similar solutions of the corresponding equations
are found analytically. They describe the formation of a finite time
singularity, with all length scales decreasing like $(t^*-t)^{1/(2-\alpha)}$,
where $t^*$ is the singularity time.

</DOC>
<DOC>
<DOCNO> 67673 </DOCNO>
Electromagnetic properties of a neutrino stream


  In a medium that contains a neutrino background in addition to the matter
particles, the neutrinos contribute to the photon self-energy as a result of
the effective electromagnetic vertex that they acquire in the presence of
matter. We calculate the contribution to the photon self-energy in a dense
plasma, due to the presence of a gas of charged particles, or neutrinos, that
moves as a whole relative to the plasma. General formulas for the transverse
and longitudinal components of the photon polarization tensor are obtained in
terms of the momentum distribution functions of the particles in the medium,
and explicit results are given for various limiting cases of practical
interest. The formulas are used to study the electromagnetic properties of a
plasma that contains a beam of neutrinos. The transverse and longitudinal
photon dispersion relations are studied in some detail. Our results do not
support the idea that neutrino streaming instabilities can develop in such a
system. We also indicate how the phenomenon of optical activity of the neutrino
gas is modified due to the velocity of the neutrino background relative to the
plasma. The general approach and results can be adapted to similar problems
involving relativistic plasmas and high-temperature gauge theories in other
environments.

</DOC>
<DOC>
<DOCNO> 7990 </DOCNO>
"Quasi two-dimensional" spin distributions in II-VI magnetic


  Spin clustering in diluted magnetic semiconductors (DMS) arises from
antiferromagnetic exchange between neighboring magnetic cations and is a strong
function of reduced dimensionality. Epitaxially-grown single monolayers and
abrupt interfaces of DMS are, however, never perfectly two-dimensional (2D) due
to the unavoidable inter-monolayer mixing of atoms during growth. Thus the
magnetization of DMS heterostructures, which is strongly modified by spin
clustering, is intermediate between that of 2D and 3D spin distributions. We
present an exact calculation of spin clustering applicable to arbitrary
distributions of magnetic spins in the growth direction. The results reveal a
surprising insensitivity of the magnetization to the form of the intermixing
profile, and identify important limits on the maximum possible magnetization.
High-field optical studies of heterostructures containing "quasi-2D" spin
distributions are compared with calculation.

</DOC>
<DOC>
<DOCNO> 70359 </DOCNO>
Neutrino-electron processes in a strongly magnetized thermal plasma


  We present a new method of calculating the rate of neutrino-electron
interactions in a strong magnetic field based on finite temperature field
theory. Using this method, in which the effect of the magnetic field on the
electron states is taken into account exactly, we calculate the rates of all of
the lowest order neutrino-electron interactions in a plasma. As an example of
the use of this technique, we explicitly calculate the rate at which neutrinos
and antineutrinos annihilate in a highly magnetized plasma, and compare that to
the rate in an unmagnetized plasma. The most important channel for energy
deposition is the gyromagnetic absorption of a neutrino-antineutrino pair on an
electron or positron in the plasma ($\nu\bar{\nu} e^\pm\leftrightarrow e^\pm$).
Our results show that the rate of annihilation increases with the magnetic
field strength once it reaches a certain critical value, which is dependent on
the incident neutrino energies and the ambient temperature of the plasma. It is
also shown that the annihilation rates are strongly dependent on the angle
between the incident particles and the direction of the magnetic field. If
sufficiently strong fields exist in the regions surrounding the core of a type
II supernovae or in the central engines of gamma ray bursts, these processes
will lead to more efficient plasma heating mechanism than in an unmagnetized
medium, and moreover, one which is intrinsically anisotropic.

</DOC>
<DOC>
<DOCNO> 11957 </DOCNO>
Ground state properties of a one-dimensional condensate of hard core


  The exact N-particle ground state wave function for a one-dimensional
condensate of hard core bosons in a harmonic trap is employed to obtain
accurate numerical results for the one-particle density matrix, occupation
number distribution of the natural orbitals, and momentum distribution. Our
results show that the occupation of the lowest orbital varies as N^{0.59}, in
contrast to N^{0.5} for a spatially uniform system, and N for a true BEC.

</DOC>
<DOC>
<DOCNO> 121730 </DOCNO>
Envelope tomography of long-period variable stars: I. The Schwarzschild


  This paper is the first one in a series devoted to the study of the dynamics
of the atmospheres of long-period variable stars. Results from a two-month-long
monitoring of the Mira variables RT Cyg and X Oph around maximum light with the
ELODIE spectrograph at the Haute-Provence Observatory are presented. The
monitoring covers phases 0.80 to 1.16 for RT Cyg and phases 0.83 to 1.04 for X
Oph. The cross-correlation profile of the spectrum of RT Cyg with a K0 III mask
confirms that the absorption lines of RT Cyg in the optical domain appear
double around maximum light. No line doubling was found in the optical spectrum
of X Oph around maximum light, indicating that this feature is not common to
all long-period variables. This paper also presents the application to RT Cyg
of a new tomographic technique deriving the velocity field across the
atmosphere by cross-correlating the optical spectrum with numerical masks
constructed from synthetic spectra and probing layers of increasing depths.
This technique reveals that both the temporal evolution of the line doubling,
and its variation with depth in the atmosphere of RT Cyg, are consistent with
the ``Schwarzschild scenario''. This scenario relates the temporal evolution of
the red and blue peaks of the double absorption lines to the progression of a
shock wave in the atmosphere. The temporal evolution of the Balmer Halpha, H
beta, Hgamma and Hdelta emission lines around maximum light is also presented
for RT Cyg and X Oph. The velocity variations of Halpha and of the absorption
lines are discussed in the framework of two competing models for the formation
of Balmer emission lines in long-period variable stars.

</DOC>
<DOC>
<DOCNO> 102888 </DOCNO>
Harmonic Twistor Formalism and Transgression on Hyperk\"ahler manifolds


  In this paper we continue our study of the fourth order transgression on
hyper\"ahler manifolds introduced in the previous paper. We give a local
construction for the fourth-order transgression of the Chern character form of
an arbitrary vector bundle supplied with a self-dual connection on a four
dimensional hyperk\"ahler manifold. The construction is based on the harmonic
twistor formalism. Remarkably, the resulted expression for the fourth order
transgression is given in terms of the determinant of the
$\bar{\partial}$-operator defined on fibers of the twistor fibration.

</DOC>
<DOC>
<DOCNO> 121959 </DOCNO>
Proper Motion Measurements with the VLA: I. Wide-field Imaging and Pulse


  The pulsar velocity distribution provides information about the binary
history of pulsar progenitors as well as asymmetries of the supernova events in
which pulsars are born. Studies of local pulsars present a biased view of this
distribution, since they preferentially select low velocity pulsars that have
remained near their birthplaces in the Galactic plane. Using the VLA, we have
studied the proper motions of a large sample of distant pulsars. These pulsars
are generally faint, and the expected proper motions are small. In this paper,
we describe the data analysis techniques that we have developed to allow
precise astrometric measurements of faint sources with the VLA. These
techniques include ``gating'' the VLA correlator to increase the
signal-to-noise ratio of the pulsar by gathering data only during the pulse.
Wide-field imaging techniques, including multiband imaging to account for
bandwidth smearing, were used to allow identification of multiple in-beam
background sources for astrometric calibration. We present the analysis of
three pulsars, and demonstrate that astrometric accuracy of about ten
milliarcseconds can be obtained for individual sources with our technique,
allowing measurement of proper motions with errors of only a few
milliarcseconds per year over our seven year baseline.

</DOC>
<DOC>
<DOCNO> 70957 </DOCNO>
Fully supersymmetric CP violations in the kaon system


  We show that, on the contrary to the usual claims, fully supersymmetric CP
violations in the kaon system are possible through the gluino mediated flavor
changing interactions. Both $\epsilon_K$ and ${\rm Re} (\epsilon' /
\epsilon_K)$ can be accommodated for relatively large $\tan\beta$ without any
fine tunings or contradictions to the FCNC and EDM constraints.

</DOC>
<DOC>
<DOCNO> 122820 </DOCNO>
Trans-Relativistic Blast Waves in Supernovae as Gamma-Ray Burst


  We investigate the acceleration of shock waves to relativistic velocities in
the outer layers of exploding stars. By concentrating the explosion energy in
the outermost ejecta, such trans-relativistic blast waves can serve as the
progenitors of gamma-ray bursts (GRBs); in particular, the ``baryon-loading''
problem that plagues many models of GRBs is circumvented. We present physically
motivated and numerically validated analytic expressions to describe
trans-relativistic blast waves in supernovae. We find that relativistic ejecta
are enhanced in more centrally condensed envelopes, e.g., for radiative
envelopes, when the luminosity approaches the Eddington limit. We present
convenient formulae for estimating the relativistic ejecta from a given
progenitor. We apply our analytic and numerical methods to a model of SN
1998bw, finding significantly enhanced relativistic ejecta compared to previous
studies. We propose that GRB 980425 is associated with SN 1998bw and may have
resulted from an approximately spherical explosion producing ~10^-6 M_sun of
mildly relativistic ejecta with mean Lorentz factor ~2, which then interacted
with a dense circumstellar wind with mass loss rate ~few x 10^-4 M_sun/yr. A
highly asymmetric explosion is not required. An extreme model of ``hypernova''
explosions in massive stars is able to account for the energetics and
relativistic ejecta velocities required by many of the observed cosmological
GRBs. We present simplified models of explosions resulting from
accretion-induced collapse of white dwarfs and phase transitions of neutron
stars. While we find increased energies in relativistic ejecta compared to
previous studies, these explosions are unlikely to be observed at cosmological
distances with current detectors. (abridged)

</DOC>
<DOC>
<DOCNO> 72318 </DOCNO>
Cosmology of Dilatonic Brane World


  We study cosmological solutions in the dilatonic brane world models. The
effective four-dimensional equations on the brane are analyzed for the models
with one positive tension brane and two branes with tensions of opposite signs.
Just as in the non-dilatonic brane case, the conventional Friedmann equations
of the four-dimensional universe are reproduced to the leading order in matter
energy density for the model with one brane and the introduction of a radion
potential is required in order to reproduce the Friedmann equations with the
correct sign for the model with two branes.

</DOC>
<DOC>
<DOCNO> 150335 </DOCNO>
A new massive vector field theory


  In this paper, we put forth a new massive spin-1 field theory. In contrast to
the quantization of traditional vector field, the quantization of the new
vector field is carried out in a natural way. The Lorentz invariance of the
theory is discussed, where owing to an interesting feature of the new vector
field, the Lorentz invariance has a special meaning. In term of formalism
analogical to QED(i. e. spinor QED), we develop the quantum electrodynamics
concerning the new spin-1 particles, say, vector QED, where the Feynman rules
are given. The renormalizability of vector QED is manifest without the aid of
Higgs mechanism. As an example, the polarization cross section $\sigma_{polar}$
for $e^+ e^-\to f^+ f^-$ is calculated in the lowest order. It turns out that
$\sigma_{polar}\sim 0$ and the momentum of $f^+$ and $f^-$ is purely
longitudinal.

</DOC>
<DOC>
<DOCNO> 119620 </DOCNO>
Clustering of Galaxy Clusters in CDM Universes


  We use very large cosmological N--body simulations to obtain accurate
predictions for the two-point correlations and power spectra of mass-limited
samples of galaxy clusters. We consider two currently popular cold dark matter
(CDM) cosmogonies, a critical density model ($\tau$CDM) and a flat low density
model with a cosmological constant ($\Lambda$CDM). Our simulations each use
$10^9$ particles to follow the mass distribution within cubes of side
$2h^{-1}$Gpc ($\tau$CDM) and $3h^{-1}$Gpc ($\Lambda$CDM) with a force
resolution better than $10^{-4}$ of the cube side. We investigate how the
predicted cluster correlations increase for samples of increasing mass and
decreasing abundance. Very similar behaviour is found in the two cases. The
correlation length increases from $r_0=12$ -- 13$h^{-1}$Mpc for samples with
mean separation $d_{\rm c}=30h^{-1}$Mpc to $r_0=22$-- 27$h^{-1}$Mpc for samples
with $d_{\rm c}=100h^{-1}$Mpc. The lower value here corresponds to $\tau$CDM
and the upper to $\Lambda$CDM. The power spectra of these cluster samples are
accurately parallel to those of the mass over more than a decade in scale. Both
correlation lengths and power spectrum biases can be predicted to better than
10% using the simple model of Sheth, Mo & Tormen (2000). This prediction
requires only the linear mass power spectrum and has no adjustable parameters.
We compare our predictions with published results for the APM cluster sample.
The observed variation of correlation length with richness agrees well with the
models, particularly for $\Lambda$CDM. The observed power spectrum (for a
cluster sample of mean separation $d_{\rm c}=31h^{-1}$Mpc) lies significantly
above the predictions of both models.

</DOC>
<DOC>
<DOCNO> 80625 </DOCNO>
Monopole classical solutions and the vacuum structure in lattice gauge


  Classical solutions corresponding to monopole-antimonopole pairs are found in
3d and 4d SU(2) and U(1) lattice gauge theories. The stability of these
solutions in different theories is studied.

</DOC>
<DOC>
<DOCNO> 118197 </DOCNO>
Near Infrared Photometry of Galactic Globular Clusters M56 and M15.


  Infrared JKs-band photometry of the Galactic globular clusters M15 and, for
the first time, M56 is presented. We estimated the reddening
(E(B-V)=0.18+/-0.08 mag) and distance modulus ((m-M)_V=15.43+/-0.30 mag)
towards the poorly studied globular cluster M56. We combined our data with
observations of other clusters from the literature (12 in total) to extend the
[Fe/H] vs. Red Giant Branch (RGB) slope relation towards metal-poor clusters.
Our best fit yields to [Fe/H]=-3.40(+/-0.22)-27.74(+/-2.35)x(RGB Slope), with
an r.m.s.=0.20. The broader metallicity baseline greatly reduced the
uncertainties compared to other existing calibrations. We confirmed a
previously obtained calibration of the relation between the RGB color
(J-Ks)_0(RGB) at M_Ks=-5.5 vs. [Fe/H]:
[Fe/H]=-6.90(+/-0.99)+6.63(+/-1.05)x(J-Ks)_0(RGB) with an r.m.s.=0.33. Finally,
using the new RGB slope calibration we estimated the abundance of the super
metal-rich cluster Liller 1 [Fe/H]=+0.34+/-0.22.

</DOC>
<DOC>
<DOCNO> 69375 </DOCNO>
New Insights into the Perturbative Structure of Electroweak Sudakov


  To match the expected experimental precision at future linear colliders,
improved theoretical predictions beyond next-to-leading order are required. At
the anticipated energy scale of sqrt(s)=1 TeV the electroweak virtual
corrections are strongly enhanced by collinear-soft Sudakov logarithms of the
form log^2(s/M^2), with M being the generic mass scale of the W and Z bosons.
By choosing an appropriate gauge, we have developed a formalism to calculate
such corrections for arbitrary electroweak processes. As an example we consider
in this letter the process e^+e^- --> f fbar and study the perturbative
structure of the electroweak Sudakov logarithms by means of an explicit
two-loop calculation. In this way we investigate how the Standard Model, with
its mass gap between the photon and Z boson in the neutral sector, compares to
unbroken theories like QED and QCD. In contrast to what is known for unbroken
theories we find that the Sudakov logarithms are not exclusively given by the
so-called rainbow diagrams, owing to the mass gap and the charged-current
interactions. In spite of this, we nevertheless observe that the two-loop
corrections are consistent with an exponentiation of the one-loop corrections.
In this sense the Standard Model behaves like an unbroken theory at high
energies.

</DOC>
<DOC>
<DOCNO> 69426 </DOCNO>
Squeezed Fermions at Relativistic Heavy Ion Colliders


  Large back-to-back correlations of observable fermion -- anti-fermion pairs
are predicted to appear, if the mass of the fermions is modified in a
thermalized medium. The back-to-back correlations of protons and anti-protons
are experimentally observable in ultra-relativistic heavy ion collisions,
similarly to the Andreev reflection of electrons off the boundary of a
superconductor. While quantum statistics suppresses the probability of
observing pairs of fermions with nearby momenta, the fermionic back-to-back
correlations are positive and of similar strength to bosonic back-to-back
correlations.

</DOC>
<DOC>
<DOCNO> 9324 </DOCNO>
Steady State of microemulsions in shear flow


  Steady-state properties of microemulsions in shear flow are studied in the
context of a Ginzburg-Landau free-energy approach. Explicit expressions are
given for the structure factor and the time correlation function at the one
loop level of approximation. Our results predict a four-peak pattern for the
structure factor, implying the simultaneous presence of interfaces aligned with
two different orientations.
 Due to the peculiar interface structure a non-monotonous relaxation of the
time correlator is also found.

</DOC>
<DOC>
<DOCNO> 121498 </DOCNO>
A Deep, Wide-Field H-alpha Survey of Nearby Clusters of Galaxies


  We present a progress report on an ongoing H-alpha imaging survey of nearby
clusters of galaxies. Four clusters have been surveyed to date: A1367, A1656,
A347 and A569. A preliminary comparison of H-alpha luminosity functions
obtained from our imaging survey with those from the prism survey reveals a
significant level of incompleteness in the latter. This in turn is due to a
combination of insensitivity to low-luminosity emission-line galaxies and to
brighter galaxies with weak extended H-alpha emission. The survey has also
revealed a unique population of clustered dwarf emission-line objects which may
be the results of recent tidal encounters between larger gas-rich galaxies.

</DOC>
<DOC>
<DOCNO> 170746 </DOCNO>
Does nonorthogonality necessarily imply nonmaximal entanglement ?


  We show that bipartite entanglements involving non-orthogonal states are {\it
necessarily nonmaximally} entangled, however {\it small} the non-orthogonality
may be. How the deviation from maximal entanglement is related to
nonorthogonality is quantified by using two independent measures of
entanglement corresponding to the violation of Bell's inequality and the
entropy measure respectively. This result is true even if one of the subsystems
has orthogonal states. An application of this is that a maximal violation of
Bell's inequality in entangled neutral kaons is not possible in the presence of
CP violation.

</DOC>
<DOC>
<DOCNO> 120062 </DOCNO>
Constraints on Cold H_2 Clouds from Gravitational Microlensing Searches


  It has been proposed that the Galaxy might contain a population of cold
clouds in numbers sufficient to account for a substantial fraction of the total
mass of the Galaxy. These clouds would have masses of the order of 10^{-3}
Solar mass and sizes of the order of 10 AU. We consider here the lensing
effects of such clouds on the light from background stars. A semianalytical
formalism for calculation of the magnification event rate produced by such
gaseous lensing is developed, taking into account the spatial distribution of
the dark matter in the Galaxy, the velocity distribution of the lensing clouds
and source stars, and motion of the observer. Event rates are calculated for
the case of gaseous lensing of stars in the Large Magellanic Cloud and results
are directly compared with the results of the search for gravitational
microlensing events undertaken by the MACHO collaboration. The MACHO experiment
strongly constrains the properties of the proposed molecular clouds, but does
not completely rule them out. Future monitoring programs will either detect or
more strongly constrain this proposed population.

</DOC>
<DOC>
<DOCNO> 8447 </DOCNO>
Theory of four-wave mixing of matter waves from a Bose-Einstein


  A recent experiment [Deng et al., Nature 398, 218(1999)] demonstrated
four-wave mixing of matter wavepackets created from a Bose-Einstein condensate.
The experiment utilized light pulses to create two high-momentum wavepackets
via Bragg diffraction from a stationary Bose-Einstein condensate. The
high-momentum components and the initial low momentum condensate interact to
form a new momentum component due to the nonlinear self-interaction of the
bosonic atoms. We develop a three-dimensional quantum mechanical description,
based on the slowly-varying-envelope approximation, for four-wave mixing in
Bose-Einstein condensates using the time-dependent Gross-Pitaevskii equation.
We apply this description to describe the experimental observations and to make
predictions. We examine the role of phase-modulation, momentum and energy
conservation (i.e., phase-matching), and particle number conservation in
four-wave mixing of matter waves, and develop simple models for understanding
our numerical results.

</DOC>
<DOC>
<DOCNO> 12641 </DOCNO>
Effects of van-Hove singularities on the upper critical field


  We present a study of the superconducting pairing susceptibility $K_T(r)$ for
a two-dimensional isotropic system with a strong power-law divergence in the
density of states $N(\epsilon) \sim \epsilon^{-1+\frac{1}{b}}$, $b>1$. We show
that the pair propagator has the scaling form, $K_T(r)=r^{b-3} F(T^{1/b} r)$.
An anomalous short-range behavior is found, leading straightforwardly to
positive curvature in the upper critical field, for $b\lesssim 2$ and to a zero
temperature divergence, $H_{c2} \sim T^{-2+\frac{4}{b}}$, for $b>2$.

</DOC>
<DOC>
<DOCNO> 122321 </DOCNO>
The Chandra Multi-wavelength Project (ChaMP): a serendipitous survey


  The launch of the Chandra X-ray Observatory in July 1999 opened a new era in
X-ray astronomy. Its unprecedented, <0.5" spatial resolution and low background
are providing views of the X-ray sky 10-100 times fainter than previously
possible. We have initiated a serendipitous survey (ChaMP) using Chandra
archival data to flux limits covering the range between those reached by
current satellites and those of the small area Chandra deep surveys. We
estimate the survey will cover ~5 sq.deg./year to X-ray fluxes (2-10 keV) in
the range 1E(-13)-6E(-16) erg/cm^2/s discovering ~2000 new X-ray sources, ~80%
of which are expected to be AGN. The ChaMP has two parts, the extragalactic
survey (ChaMP) and the galactic plane survey (ChaMPlane). ChaMP promises
profoundly new science return on a number of key questions at the current
frontier of many areas of astronomy including (1) locating and studying high
redshift clusters and so constraining cosmological parameters (2) defining the
true population of AGN, including those that are absorbed, and so constraining
the accretion history of the universe, (3) filling in the gap in the
luminosity/redshift plane between Chandra deep and previous surveys in studying
the CXRB, (4) studying coronal emission from late-type stars and (5) search for
CVs and quiescent Low-Mass X-ray Binaries (qLXMBs) to measure their luminosity
functions. In this paper we summarize the status, predictions and initial
results from the X-ray analysis and optical imaging.

</DOC>
<DOC>
<DOCNO> 40211 </DOCNO>
Search for Large Extra Dimensions in Dielectron and Diphoton Production


  We report a search for effects of large extra spatial dimensions in ppbar
collisions at a center-of-mass energy of 1.8 TeV with the DZero detector, using
events containing a pair of electrons or photons. The data are in good
agreement with the expected background and do not exhibit evidence for large
extra dimensions. We set the most restrictive lower limits to date, at the 95%
confidence level, on the effective Planck scale between 1.0 TeV and 1.4 TeV for
several formalisms and numbers of extra dimensions.

</DOC>
<DOC>
<DOCNO> 169730 </DOCNO>
Integrity bases for local invariants of composite quantum systems


  Unitary group branchings appropriate to the calculation of local invariants
of density matrices of composite quantum systems are formulated using the
method of $S$-function plethysms. From this, the generating function for the
number of invariants at each degree in the density matrix can be computed. For
the case of two two-level systems the generating function is $F(q) = 1 + q +
4q^{2} + 6 q^{3} + 16 q^{4} + 23 q^{5} + 52 q^{6} + 77 q^{7} + 150 q^{8} + 224
q^{9} + 396 q^{10} + 583 q^{11}+ O(q^{12})$. Factorisation of such series leads
in principle to the identification of an integrity basis of algebraically
independent invariants. This note replaces Appendix B of our paper\cite{us} J
Phys {\bf A33} (2000) 1895-1914 (\texttt{quant-ph/0001076}) which is incorrect.

</DOC>
<DOC>
<DOCNO> 100565 </DOCNO>
Hypersequents and the Proof Theory of Intuitionistic Fuzzy Logic


  Takeuti and Titani have introduced and investigated a logic they called
intuitionistic fuzzy logic. This logic is characterized as the first-order
Goedel logic based on the truth value set [0,1]. The logic is known to be
axiomatizable, but no deduction system amenable to proof-theoretic, and hence,
computational treatment, has been known. Such a system is presented here, based
on previous work on hypersequent calculi for propositional Goedel logics by
Avron. It is shown that the system is sound and complete, and allows
cut-elimination. A question by Takano regarding the eliminability of the
Takeuti-Titani density rule is answered affirmatively.

</DOC>
<DOC>
<DOCNO> 68980 </DOCNO>
The lightest Higgs mass in supersymmetric models with extra dimensions


  In the four-dimensional supersymmetric standard model extended with gauge
singlets the lightest Higgs boson mass, $M_H$, has an important contribution
proportional to the squared of the superpotential coupling $\lambda$ of
singlets to Higgs fields, $\lambda SH_1\cdot H_2$. The requirement of
perturbativity up to the unification scale yields an upper bound on $M_H\sim
140$ GeV. In extensions to theories with (longitudinal) extra dimensions at the
TeV where such coupling exists and massive Kaluza-Klein states fall into N=2
representations, if either of the Higgs or singlet fields live in the bulk of
the extra dimensions, the $\beta$-function of $\lambda$ is suppressed due to
the absence of anomalous dimension of hypermultiplets to leading order. This
implies a slower running of $\lambda$ and an enhancement of its low energy
value. The $M_H$ upper bound increases to values $M_H\lesssim 165$ GeV.

</DOC>
<DOC>
<DOCNO> 151553 </DOCNO>
Space-Time Noncommutativity, Discreteness of Time and Unitarity


  Violation of unitarity for noncommutative field theory on compact space-times
is considered. Although such theories are free of ultraviolet divergences, they
still violate unitarity while in a usual field theory such a violation occurs
when the theory is nonrenormalizable. The compactness of space-like coordinates
implies discreteness of the time variable which leads to appearance of
unphysical modes and violation of unitarity even in the absence of a
star-product in the interaction terms. Thus, this conclusion holds also for
other quantum field theories with discrete time. Violation of causality, among
others, occurs also as the nonvanishing of the commutation relations between
observables at space-like distances with a typical scale of noncommutativity.
While this feature allows for a possible violation of the spin-statistics
theorem, such a violation does not rescue the situation but makes the scale of
causality violation as the inverse of the mass appearing in the considered
model, i.e., even more severe. We also stress the role of smearing over the
noncommutative coordinates entering the field operator symbols.

</DOC>
<DOC>
<DOCNO> 151962 </DOCNO>
Chern-Simons Terms on Noncommutative Branes


  We write down couplings of the fields on a single BPS Dp-brane with
noncommutative world-volume coordinates to the RR-forms in type II theories, in
a manifestly background independent way. This generalises the usual
Chern-Simons action for a commutative Dp-brane. We show that the noncommutative
Chern-Simons terms can be mapped to Myers terms on a collection of infinitely
many D-instantons. We also propose Chern-Simons couplings for unstable non-BPS
branes, and show that condensation of noncommutative tachyons on these branes
leads to the correct Myers terms on the decay products.

</DOC>
<DOC>
<DOCNO> 123159 </DOCNO>
HI Emission and Absorption in the Southern Galactic Plane Survey


  We present preliminary results from the Southern Galactic Plane Survey (SGPS)
Test Region and Parkes data. As part of the pilot project for the Southern
Galactic Plane Survey, observations of a Test Region (325.5 deg < l < 333.5
deg; -0.5 deg < b < 3.5 deg) were completed in December 1998. Single dish
observations of the full survey region (253 deg < l < 358 deg; |b| <1 deg) with
the Parkes Radio Telescope were completed in March 2000. We present a sample of
SGPS HI data with particular attention to the smallest and largest scale
structures seen in absorption and emission, respectively. On the large scale,
we detect many prominent HI shells. On the small scale, we note extremely
compact, cold clouds seen in HI self-absorption. We explore how these two
classes of objects probe opposite ends of the HI spatial power spectrum.

</DOC>
<DOC>
<DOCNO> 169960 </DOCNO>
How entangled can two couples get?


  We describe a pure state of four qubits whose single-qubit density matrices
are all maximally mixed and whose average entanglement as a system of two pairs
of qubits appears to be maximal.

</DOC>
<DOC>
<DOCNO> 102248 </DOCNO>
A Variational Formulation of Optimal Nonlinear Estimation


  We propose a variational method to solve all three estimation problems for
nonlinear stochastic dynamical systems: prediction, filtering, and smoothing.
Our new approach is based upon a proper choice of cost function, termed the
{\it effective action}. We show that this functional of time-histories is the
unique statistically well-founded cost function to determine most probable
histories within empirical ensembles. The ensemble dispersion about the sample
mean history can also be obtained from the Hessian of the cost function. We
show that the effective action can be calculated by a variational prescription,
which generalizes the ``sweep method'' used in optimal linear estimation. An
iterative numerical scheme results which converges globally to the variational
estimator. This scheme involves integrating forward in time a ``perturbed''
Fokker-Planck equation, very closely related to the Kushner-Stratonovich
equation for optimal filtering, and an adjoint equation backward in time,
similarly related to the Pardoux-Kushner equation for optimal smoothing. The
variational estimator enjoys a somewhat weaker property, which we call ``mean
optimality''. However, the variational scheme has the principal
advantage---crucial for practical applications---that it admits a wide variety
of finite-dimensional moment-closure approximations. The moment approximations
are derived reductively from the Euler-Lagrange variational formulation and
preserve the good structural properties of the optimal estimator.

</DOC>
<DOC>
<DOCNO> 13046 </DOCNO>
Non-perturbative approach to the attractive Hubbard model


  A non-perturbative approach to the single-band attractive Hubbard model is
presented in the general context of functional derivative approaches to
many-body theories. As in previous work on the repulsive model, the first step
is based on a local-field type ansatz, on enforcement of the Pauli principle
and a number of crucial sum-rules. The Mermin-Wagner theorem in two dimensions
is automatically satisfied. At this level, two-particle self-consistency has
been achieved. In the second step of the approximation, an improved expression
for the self-energy is obtained by using the results of the first step in an
exact expression for the self-energy where the high- and low-frequency
behaviors appear separately. The result is a cooperon-like formula. The
required vertex corrections are included in this self-energy expression, as
required by the absence of a Migdal theorem for this problem. Other approaches
to the attractive Hubbard model are critically compared. Physical consequences
of the present approach and agreement with Monte Carlo simulations are
demonstrated in the accompanying paper (following this one).

</DOC>
<DOC>
<DOCNO> 71385 </DOCNO>
Trace anomaly driven inflation


  This paper investigates Starobinsky's model of inflation driven by the trace
anomaly of conformally coupled matter fields. This model does not suffer from
the problem of contrived initial conditions that occurs in most models of
inflation driven by a scalar field. The universe can be nucleated
semi-classically by a cosmological instanton that is much larger than the
Planck scale provided there are sufficiently many matter fields. There are two
cosmological instantons: the four sphere and a new ``double bubble'' solution.
This paper considers a universe nucleated by the four sphere. The AdS/CFT
correspondence is used to calculate the correlation function for scalar and
tensor metric perturbations during the ensuing de Sitter phase. The analytic
structure of the scalar and tensor propagators is discussed in detail.
Observational constraints on the model are discussed. Quantum loops of matter
fields are shown to strongly suppress short scale metric perturbations, which
implies that short distance modifications of gravity would probably not be
observable in the cosmic microwave background. This is probably true for any
model of inflation provided there are sufficiently many matter fields. This
point is illustrated by a comparison of anomaly driven inflation in four
dimensions and in a Randall-Sundrum brane-world model.

</DOC>
<DOC>
<DOCNO> 100172 </DOCNO>
Families of singular rational curves


  Let X be a projective variety which is covered by a family of rational curves
of minimal degree. The classic bend-and-break argument of Mori asserts that if
x and y are two general points, then there are at most finitely many curves in
that family which contain both x and y. In this work we shed some light on the
question as to whether two sufficiently general points actually define a unique
curve.
  As an immediate corollary to the results of this paper, we give a
characterization of projective spaces which improves on the known
generalizations of Kobayashi-Ochiai's theorem.

</DOC>
<DOC>
<DOCNO> 119318 </DOCNO>
Discovery of 424 ms pulsations from the radio-quiet neutron star in the


  The central source of the supernova remnant PKS 1209-52 was observed with the
Advanced CCD Imaging Spectrometer aboard Chandra X-ray observatory on 2000
January 6-7. The use of the Continuos Clocking mode allowed us to perform the
timing analysis of the data with time resolution of 2.85 ms and to find a
period P=0.42412927+/-2.3e-7 s. The detection of this short period proves that
the source is a neutron star. It may be either an active pulsar with
unfavorably directed radio beam or a truly radio-silent neutron star whose
X-ray pulsations are caused by a nonuniform distribution of surface
temperature. To infer the actual properties of this neutron star, the period
derivative should be measured.

</DOC>
<DOC>
<DOCNO> 80936 </DOCNO>
What happens to Lattice Fermion near Continuum Limit?


  A Ginsparg-Wilson Relation (GWR) is obtained in the presence of chiral
symmetry breaking terms. It leads to the PCAC relation as well as an anomaly
relation on the lattice. For general fermions, the deviation from the exact GWR
is getting small when the block-spin transformations are performed iteratively.
Based on a simple geometrical interpretation of the Dirac operator satisfying
the GWR, we find some physical properties shared by the lattice fermions near
the continuum limit. In two-dimensions, we explicitly construct the GW Dirac
operator by using a conformal mapping.

</DOC>
<DOC>
<DOCNO> 178831 </DOCNO>
The hep reaction and the solar neutrino problem


  The results of a new calculation of the astrophysical S-factor for the proton
weak capture on 3He are here reviewed. The methods used to obtain very accurate
initial and final state wave functions and to construct the nuclear weak
current operator are described. Finally the implications of these results for
the Super-Kamiokande solar neutrino data are discussed.

</DOC>
<DOC>
<DOCNO> 40272 </DOCNO>
New Limits on the Production of Magnetic Monopoles at Fermilab


  First results from an experiment (Fermilab E882) searching for magnetically
charged particles bound to elements from the CDF and D{\O}detectors are
reported. The experiment is described, and limits on magnetic monopole pair
production cross sections for magnetic charges 1, 2, 3, and 6 times the Dirac
pole strength are presented. These limits ($\sim1$ pb), hundreds of times
smaller than those found in previous direct accelerator-based searches, use
simple model assumptions for the photonic production of monopoles, as does the
extraction of mass limits in the hundreds of GeV range.

</DOC>
<DOC>
<DOCNO> 101615 </DOCNO>
Counting dimensions of L-harmonic functions


  In this article, we will consider second order uniformly elliptic operators
of divergence form defined on R^n with measurable coefficients. Mainly, we
will give estimates on the dimension of space of solutions that grow at most
polynomially of degree d. More precisely, in terms of a rectangular coordinate
system {x_1,...,x_n}, a second order uniformly elliptic operator of divergence
form, L, acting on a function f in H^1_loc(R^n) is given by
  Lf = sum_{ij} d/dx_i (a^{ij}(x) df/dx_j)
  where (a^{ij}(x)) is an n x n symmetric matrix satisfying the ellipticity
bounds
  \lambda I <= (a^{ij}) <= Lambda I
  for some constants 0 < lambda <= Lambda < \infty. Other than the ellipticity
bounds, we only assume that the coefficients (a_{ij}) are merely measurable
functions.

</DOC>
<DOC>
<DOCNO> 102870 </DOCNO>
Hydrodynamic equation for a deposition model


  We show that the two-component system of hyperbolic conservation laws
$\partial_t \rho + \partial_x (\rho u) =0 = \partial_t u + \partial_x \rho$
appears naturally in the formally computed hydrodynamic limit of some randomly
growing interface models, and we study some properties of this system. We show
that the two-component system of hyperbolic conservation laws $\partial_t \rho
+ \partial_x (\rho u) =0 = \partial_t u + \partial_x \rho$ appears naturally in
the formally computed hydrodynamic limit of some randomly growing interface
models, and we study some properties of this system.

</DOC>
<DOC>
<DOCNO> 178774 </DOCNO>
Theoretical study of the decay-out spin of superdeformed bands in the Dy


  Decay of the superdeformed bands have been studied mainly concentrating upon
the decay-out spin, which is sensitive to the tunneling probability between the
super- and normal-deformed wells. Although the basic features are well
understood by the calculations, it is difficult to precisely reproduce the
decay-out spins in some cases. Comparison of the systematic calculations with
experimental data reveals that values of the calculated decay-out spins scatter
more broadly around the average value in both the $A \approx$ 150 and 190
regions, which reflects the variety of calculated tunneling probability in each
band.

</DOC>
<DOC>
<DOCNO> 11516 </DOCNO>
Schwinger-Keldysh semionic approach for quantum spin systems


  We derive a path-integral Schwinger-Keldysh approach for quantum spin
systems. This is achieved by means of a semionic representation of spins as
fermions with imaginary chemical potential. The major simplifying feature in
comparison with other representations (Holstein-Primakoff, Dyson-Maleev, slave
bosons/fermions etc) is that the local constraint is taken into account
exactly. As a result, the standard diagram technique with usual Feynman codex
is constructed. We illustrate the application of this technique for the N\'eel
and spin-liquid states of the AFM Heisenberg model.

</DOC>
<DOC>
<DOCNO> 122755 </DOCNO>
Concluding Remarks on New Cosmological Data and the Values of the


  I review the reason for considering the prime purpose of the program of
measurements of the fundamental parameters of cosmology to be the tests of
cosmological models. I comment on the philosophy by which we are approaching
this goal, offer an assessment of where we stand, and present some thoughts on
where the tests may be headed.

</DOC>
<DOC>
<DOCNO> 123157 </DOCNO>
Mining the Blazar Sky


  We present the results of our methods to "mine" the blazar sky, i.e., select
blazar candidates with very high efficiency. These are based on the
cross-correlation between public radio and X-ray catalogs and have resulted in
two surveys, the Deep X-ray Radio Blazar Survey (DXRBS) and the "Sedentary" BL
Lac survey. We show that data mining is vital to select sizeable, deep samples
of these rare active galactic nuclei and we touch upon the identification
problems which deeper surveys will face.

</DOC>
<DOC>
<DOCNO> 70816 </DOCNO>
Adiabatic and entropy perturbations from inflation


  We study adiabatic (curvature) and entropy (isocurvature) perturbations
produced during a period of cosmological inflation that is driven by multiple
scalar fields with an arbitrary interaction potential. A local rotation in
field space is performed to separate out the adiabatic and entropy modes. The
resulting field equations show explicitly how on large scales entropy
perturbations can source adiabatic perturbations if the background solution
follows a curved trajectory in field space, and how adiabatic perturbations
cannot source entropy perturbations in the long-wavelength limit. It is the
effective mass of the entropy field that determines the amplitude of entropy
perturbations during inflation. We present two applications of the equations.
First, we show why one in general expects the adiabatic and entropy
perturbations to be correlated at the end of inflation, and calculate the
cross-correlation in the context of a double inflation model with two
non-interacting fields. Second, we consider two-field preheating after
inflation, examining conditions under which entropy perturbations can alter the
large-scale curvature perturbation and showing how our new formalism has
advantages in numerical stability when the background solution follows a
non-trivial trajectory in field space.

</DOC>
<DOC>
<DOCNO> 7903 </DOCNO>
One dimensional model for doubly degenerate electrons


  A Hubbard-like model with SU(4) symmetry for electrons with two-fold orbital
degeneracy is studied extensively. Exact solution in one dimension is derived
by means of Bethe ansatz, where the sites are supposed to be occupied by at
most two electrons. The features of ground state and excited states for
repulsive coupling are shown. For finite N number of electrons, the
configurations of quantum numbers are given explicitly and the spectra of
excitations are obtained by solving the Bethe-ansatz equation numerically. For
infinite N, the ground state and various kinds of low-lying excitations are
obtained on the basis of thermodynamics limit.

</DOC>
<DOC>
<DOCNO> 100031 </DOCNO>
New Einstein Metrics in Dimension Five


  The purpose of this note is to introduce a new method for proving the
existence of Sasakian-Einstein metrics on certain simply connected odd
dimensional manifolds. We then apply this method to prove the existence of new
Sasakian-Einstein metrics on $\scriptstyle{S^2\times S^3}$ and on
$\scriptstyle{(S^2\times S^3)# (S^2\times S^3).}$ These give the first known
examples of non-regular Sasakian-Einstein 5-manifolds. Our method involves
describing the Sasakian-Einstein structures as links of certain isolated
hypersurface singularities, and makes use of the recent work of Demailly and
Koll\'ar, AG/9910118, who obtained new examples of K\"ahler-Einstein del Pezzo
surfaces with quotient singularities.

</DOC>
<DOC>
<DOCNO> 67899 </DOCNO>
A QCD Analysis of Polarised Parton Densities


  We present the results of a QCD fit to global data on deep-inelastic
polarised lepton-hadron scattering. We find that it is possible to fit the data
with strongly broken SU(2) flavour for the polarised sea densities. This can
easily be tested in $W$ production at polarised RHIC. The data fails to pin
down polarised singlet sea quark and gluon densities. We explore the
uncertainties in detail and show that improvement in statistics, achievable at
polarised HERA for measurement of A_1 at moderately low values of x, have large
payoffs in terms of the improvement in measurement of gluon and sea quark
densities.

</DOC>
<DOC>
<DOCNO> 84099 </DOCNO>
Can a Particle's Velocity Exceed the Speed of Light in Empty Space?


  Relative motion in space with multifractal time (fractional dimension of time
close to integer $d_{t}=1+\epsilon (r,t), \epsilon \ll 1$) for "almost"
inertial frames of reference (time is almost homogeneous and almost isotropic)
is considered. Presence in such space of absolute frames of reference and
violation of conservation laws (though, small because of the smallness of
$\epsilon$) due to the openness of all physical systems and inhomogeneiy of
time are shown. The total energy of a body moving with $v=c$ is obtained to be
finite and modified Lorentz transformations are formulated. The relation for
the total energy (and the whole theory) reduce to the known formula of the
special relativity in case of transition to the usual time with dimension equal
to one.

</DOC>
<DOC>
<DOCNO> 67647 </DOCNO>
The Case for Neutrino Oscillations


  No abstract appeared in the Proceedings, but I am adding the following
summary at the request of the X^3 people: The idea of neutrino masses is
discussed in the context of grand unified theories., and various scenarios are
presented, including the seesaw mechanism. At the end, preference is stated for
maximal mixing between $\nu_\mu$ and $\nu_\tau$, and small mixing with $\nu_e$.

</DOC>
<DOC>
<DOCNO> 119374 </DOCNO>
Active Nucleus in a Poststarburst Galaxy : KUG 1259+280


  We report the discovery of an active nucleus in a poststarburst galaxy,
KUG1259+280. High resolution X-ray imaging observations with ROSAT HRI show
that X-ray emission from KUG1259+280 is unresolved. X-ray emission from
KUG1259+280 is highly variable, an episode in which X-ray intensity changed by
a factor 2.5 within about 1300s has been detected. ROSAT PSPC spectra of this
galaxy is found to be well represented by a steep power law of photon index
4.25, and a change in the absorbing column within about a day is indicated. The
rest frame intrinsic X-ray luminosity of KUG1259+280 is found to be
3.6-4.7X10^42 erg/s similar to that of low luminosity Seyfert galaxies. Mass of
the central massive object within KUG1259+280 is estimated to be in the range
of 10^5-10^7 M_sun. Optical spectrum of the nuclear region of the galaxy is
complex and shows Balmer absorption and collisionally excited lines of [OIII],
and [NII]. The presence of forbidden emission lines and the absence of Balmer
emission lines in spectrum of KUG1259+280 could be due to photoionization by a
diluted power-law continuum modified by enhanced stellar absorption due to a
poststarburst event. Estimated Balmer line strengths free of stellar
absorptions and forbidden line strengths indicate the nucleus of KUG1259+280 to
be LINER-like in nature. However, the low-ionization forbidden line [OI]6300
usually present in LINER spectra, is not detected in the spectrum of
KUG1259+280. X-ray characteristics -- variability, point-like appearance,
luminosity and steepness of spectrum indicate that nucleus in KUG1259+280 is
active and perhaps like that of narrow-line Seyfert type 1 galaxies.

</DOC>
<DOC>
<DOCNO> 67799 </DOCNO>
Polarization of Inclusive $\Lambda_c$'s in a Hybrid Model


  A hybrid model is presented for hyperon polarization that is based on
perturbative QCD subprocesses and the recombination of polarized quarks with
scalar diquarks. The updated hybrid model is applied to $p+p\to \Lambda +X$ and
successfully reproduces the detailed kinematic dependence shown by the data.
The hybrid model is extended to include pion beams and polarized $\Lambda_c$'s.
The resulting polarization is found to be in fair agreement with recent
experiments. Predictions for the polarization dependence on $x_F$ and $p_T$ is
given.

</DOC>
<DOC>
<DOCNO> 13922 </DOCNO>
Polymer Films in the Normal-Liquid and Supercooled State: A Review of


  This paper reviews recent Monte Carlo simulation studies of the glassy
behavior in thin polymer films. The simulations employ a version of the
bond-fluctuation lattice model, in which the glass transition is driven by the
competition between a stiffening of the polymers and their dense packing in the
melt. The melt is geometrically confined between two impenetrable walls
separated by distances ranging from once to about fifteen times the bulk radius
of gyration. The confinement influences static and dynamic properties of the
films: Chains close to the wall preferentially orient parallel to it. This
orientation tendency propagates through the film and leads to a layer structure
at low temperatures and small thicknesses. The layer structure strongly
suppresses out-of-plane reorientations of the chains. In-plane reorientations
have to take place in a high density environment which gives rise to an
increase of the corresponding relaxation times. However, local density
fluctuations are enhanced if film thickness and temperature decrease. This
implies a reduction of the glass transition temperature with decreasing film
thickness.

</DOC>
<DOC>
<DOCNO> 152024 </DOCNO>
Generalised 11-dimensional supergravity


  The low-energy effective dynamics of M-theory, eleven-dimensional
supergravity, is taken off-shell in a manifestly supersymmetric superspace
formulation. We show that a previously proposed relaxation of the torsion
constraints can indeed accomodate a current supermultiplet. We comment on the
relation and application of this completely general formalism to
higher-derivative (R^4) corrections. This talk was presented by Bengt EW
Nilsson at the Triangle Meeting 2000 ``Non-perturbative Methods in Field and
String Theory'', NORDITA, Copenhagen, June 19-22, 2000, and by Martin Cederwall
at the International Conference ``Quantization, Gauge Theory and Strings'' in
memory of Efim Fradkin, Moscow, June 5-10, 2000.

</DOC>
<DOC>
<DOCNO> 71559 </DOCNO>
Regulated chiral gauge theory


  After a brief introduction to the overlap two examples relating to
topological properties of chiral fermion systems in interaction with gauge
fields are presented: It is shown how the overlap preserves the continuum
structure of exact fermionic zero modes in gauge backgrounds that are
instanton-like and why chiral anomalies are inevitable.

</DOC>
<DOC>
<DOCNO> 116528 </DOCNO>
Matching Conditions on Capillary Ripples: Polarization


  The matching conditions at the interface between two non-mixed fluids at rest
are obtained directly using the equation of movement of the whole media. This
is a non-usual point of view in hydrodynamics courses and our aim is to fix
ideas about the intrinsic information contained in the matching conditions, on
fluids in this case. Afterward, it is analyzed the polarization of the normal
modes at the interface and it is shown that this information can be achieved
through a physical analysis and reinforced later by the matching conditions. A
detailed analysis of the matching conditions is given to understand the role
that plays the continuity of the stress tensor through the interface on the
physics of the surface particle movement. The main importance of the viscosity
of each medium is deduced.

</DOC>
<DOC>
<DOCNO> 123089 </DOCNO>
WIMP searches with AMANDA-B10


  We report on the search for nearly vertical up-going muon neutrinos from WIMP
annihilations in the center of the Earth with the AMANDA-B10 detector. The
whole data sample collected in 1997, 10^9 events, has been analyzed and a final
sample of 15 up-going events is found in a restricted zenith angular region
where a signal from WIMP annihilations is expected. A preliminary upper limit
at 90% confidence level on the annihilation rate of WIMPs in the center of the
Earth is presented.

</DOC>
<DOC>
<DOCNO> 122385 </DOCNO>
Issues and methods for CMB anisotropy data reduction


  Major issues and existing methods for the reduction of CMB anisotropy data
are reviewed. An emphasis is put on the proper modelling of the data. It is
suggested that the robustness of methods could be improved by taking into
account the uncertainty of the model for finding optimal solutions.

</DOC>
<DOC>
<DOCNO> 119932 </DOCNO>
The Equilibrium Structure of Cosmological Halos: Dwarf Galaxies to X-ray


  An analytical model for the postcollapse equilibrium structure of virialized
objects which condense out of the cosmological background universe is described
and compared with observations and simulations of cosmological halos. The model
is based upon the assumption that virialized halos are isothermal, which leads
to a prediction of a unique nonsingular isothermal sphere for the equilibrium
structure, with a core density which is proportional to the mean background
density at the epoch of collapse. These predicted nonsingular isothermal
spheres are in good agreement with observations of the internal structure of
dark-matter-dominated halos from dwarf galaxies to X-ray clusters. Our model
also reproduces many of the average properties of halos in CDM simulations to
good accuracy, suggesting that it is a useful analytical approximation for
halos which form from realistic initial conditions. While CDM N-body
simulations find profiles with a central cusp, our nonsingular model matches
the simulated halos outside the innermost region well. This model may also be
of interest as a description of halos in nonstandard CDM models like
self-interacting dark matter, which have been proposed to eliminate the
discrepancy between the cuspy halos of standard CDM simulations and observed
halos with uniform-density cores.

</DOC>
<DOC>
<DOCNO> 68995 </DOCNO>
Supersymmetry at Large Distance Scales


  We propose that the UV/IR relation that underlies the AdS/CFT duality may
provide a natural mechanism by which high energy supersymmetry can have large
distance consequences. We motivate this idea via (a string realization of) the
Randall-Sundrum scenario, in which the observable matter is localized on a
matter brane separate from the Planck brane. As suggested via the holographic
interpretation of this scenario, we argue that the local dynamics of the Planck
brane - which determines the large scale 4-d geometry - is protected by the
high energy supersymmetry of the dual 4-d theory. With this assumption, we show
that the total vacuum energy naturally cancels in the effective 4-d Einstein
equation. This cancellation is robust against changes in the low energy
dynamics on the matter brane, which gets stabilized via the holographic RG
without any additional fine-tuning.

</DOC>
<DOC>
<DOCNO> 122781 </DOCNO>
Close stellar encounters with planetesimal discs: The dynamics of


  We numerically investigate the dynamics of how a close stellar fly-by
encounter of a symmetrical circumstellar planetesimal disc can give rise to the
many kinds of asymmetries and substructures attributed to the edge-on dusty
disc of Beta Pic. In addition we present new optical coronagraphic observations
of the outer parts of Beta Pic's disc, and report that the radial extent is
significantly greater than was found in previous measurements. The
northeasterly extension of the disc's midplane is now measured out to 1835au
from the star; the southwesterly component is measured out to 1450au. Hence we
use the length asymmetry induced in a distribution of simulation test particles
as the principal diagnostic feature when modelling the disc response, in order
to constrain fly-by parameters. In particular we favour a low inclination
prograde and near-parabolic orbit perturber of mass approximately 0.5 Solar
masses. These initial conditions suggest that the perturber could have been
physically associated with Beta Pic prior to the encounter. Thus we also
consider the possibility that the perturber could be bound to Beta Pic: a
consideration also of general interest where dust discs are known to exist in
binary star systems. In some of our models, we can relate groupings of
perturbed particles to the large-scale structure of the Beta Pic disc. The
groupings correspond to: high eccentricity and inclination particles that reach
apocentre and maximum height in the southwest, moderately eccentric and low
inclination particles that reach apocentre in the northeast, and relatively
unperturbed particles inside approximately 200au radius.

</DOC>
<DOC>
<DOCNO> 102037 </DOCNO>
Cocycle conjugacy of quasifree endomorphisms semigroups on the CAR


  W. Arveson has described a cocycle conjugacy class $U(\alpha)$ of
$E_0$-semigroup $\alpha$ on B(H) which is a factor of type $\rm I$. Under some
conditions on $\alpha$, there is a $E_0$-semigroup $\beta \in U(\alpha)$ being
a flow of shifts in the sence of R.T. Powers. We study quasifree endomorphisms
semigroups $\alpha$ on the hyperfinite factor $M=\pi (A(K))''$ generated by the
representations $\pi$ of the algebra of canonical anticommutation relations
A(K) over a separable Hilbert space K. The type of M can be $\rm I$, $\rm II$
or $\rm III$ depending on $\pi$. The cocycle conjugacy class $U(\alpha)$ is
described in the terms of initial isometrical semigroups in K and an analogue
of the Arveson result for the hyperfinite factors M of the type $\rm II_1$ and
$\rm III_{\lambda}, 0<\lambda <1,$ is introduced.

</DOC>
<DOC>
<DOCNO> 118355 </DOCNO>
FIRBACK Source Counts and Cosmological Implications


  FIRBACK is a one of the deepest surveys performed at 170 microns with ISOPHOT
onboard ISO, and is aimed at the study of cosmic far infrared background
sources. About 300 galaxies are detected in an area of four square degrees, and
source counts present a strong slope of 2.2 on an integral "logN-logS" plot,
which cannot be due to cosmological evolution if no K-correction is present.
The resolved sources account for less than 10% of the Cosmic Infrared
Background at 170 microns. In order to understand the nature of the sources
contributing to the CIB, and to explain deep source counts at other
wavelengths, we have developed a phenomenological model, which constrains in a
simple way the luminosity function evolution with redshift, and fits all the
existing deep source counts from the mid-infrared to the submillimetre range.
Images, materials and papers available on the FIRBACK web:
http://wwwfirback.ias.u-psud.fr wwwfirback.ias.u-psud.fr

</DOC>
<DOC>
<DOCNO> 10728 </DOCNO>
Extraction of work from a single thermal bath in the quantum regime


  The stationary state of a quantum particle strongly coupled to a quantum
thermal bath is known to be non-gibbsian, due to entanglement with the bath.
For harmonic potentials, where the system can be described by effective
temperatures, thermodynamic relations are shown to take a generalized Gibbsian
form, that may violate the Clausius inequality. For the weakly-anharmonic case
a Fokker-Planck type description is constructed. It is shown that then work can
be extracted from the bath by cyclic variation of a parameter. These apparent
violations of the second law are the consequence of quantum coherence in the
presence of the slightly off-equilibrium nature of the bath.

</DOC>
<DOC>
<DOCNO> 151505 </DOCNO>
Type-I strings on magnetised orbifolds and brane transmutation


  In the presence of internal magnetic fields, a D9 brane can acquire a D5 (or
anti-D5) R-R charge, and can therefore contribute to the corresponding tadpole.
In the resulting vacua, supersymmetry is generically broken and tachyonic
instabilities are present. However, suitable choices for the magnetic fields,
corresponding to self-dual configurations in the internal space, can yield new
chiral supersymmetric vacua with gauge groups of reduced rank, where the
magnetic energy saturates, partly or fully, the negative tension of the O5+
planes. These models contain Green-Schwarz couplings to untwisted R-R forms not
present in conventional orientifolds.

</DOC>
<DOC>
<DOCNO> 151673 </DOCNO>
Lumps in level truncated open string field theory


  The ratios of the masses of D(p-d) branes to the masses of Dp in open bosonic
string field theory are computed within the modified level truncation
approximation of Moeller, Sen and Zweibach. At the lowest non-trivial
truncation requiring the addition of new primary states, we find evidence of
rapid convergence to the expected result for 1<d<7 providing additional
evidence for the consistency of this approximation.

</DOC>
<DOC>
<DOCNO> 13846 </DOCNO>
Metallic Ferromagnetism - an Electronic Correlation Phenomenon


  New insights into the microscopic origin of itinerant ferromagnetism were
recently gained from investigations of electronic lattice models within
dynamical mean-field theory (DMFT). In particular, it is now established that
even in the one-band Hubbard model metallic ferromagnetism is stable at
intermediate values of the interaction U and density n on regular, frustrated
lattices. Furthermore, band degeneracy along with Hund's rule couplings is very
effective in stabilizing metallic ferromagnetism in a broad range of electron
fillings. DMFT also permits one to investigate more complicated correlation
models, e.g., the ferromagnetic Kondo lattice model with Coulomb interaction,
describing electrons in manganites with perovskite structure. Here we review
recent results obtained with DMFT which help to clarify the origin of
band-ferromagnetism as a correlation phenomenon.

</DOC>
<DOC>
<DOCNO> 72252 </DOCNO>
Neutrino mass due to the mixing among neutrinos and gauginos


  We consider the explanation of both data of the atmospheric neutrino and the
solar neutrino by the neutrino mass matrix derived from the mixing of neutrinos
and gauginos in the extended MSSM with an extra U(1) gauge symmetry. This
scenario directly relates the neutrino mass to supersymmetry. The structure of
the mass hierarchy and the mixing is determined only by the extra U(1)-charge
of neutrinos. Although the model is rather simple, it may be able to realize
both the small and large mixing angle solutions for the solar neutrino problem.
In particular, the large mixing angle MSW solution for the solar neutrino
problem can be easily realized. We discuss the relation between the extra
U(1)-charge and four solutions for the solar neutrino problem.

</DOC>
<DOC>
<DOCNO> 69122 </DOCNO>
Unitarity Constraints on Neutrino Mass and Mixings


  We explore the implications of imposing the constraint that two neutrino
flavors (which for definiteness we take to be muon and tau neutrinos) are
similarly coupled to the mass basis in addition to the unitarity constraints.
Implications of this scheme for specific experimental situations are discussed.

</DOC>
<DOC>
<DOCNO> 39631 </DOCNO>
High Precision Mass Measurements in $\Psi$ and $\Upsilon$ Families


  High precision mass measurements in $\Psi$ and $\Upsilon$ families performed
in 1980-1984 at the VEPP-4 collider with OLYA and MD-1 detectors are revisited.
The corrections for the new value of the electron mass are presented. The
effect of the updated radiative corrections has been calculated for the
$J/\Psi(1S)$ and $\Psi(2S)$ mass measurements.

</DOC>
<DOC>
<DOCNO> 102562 </DOCNO>
Logarithmic forms and anti-invariant forms of reflection groups


  Let W be a finite group generated by unitary reflections and A be the set of
reflecting hyperplanes. We will give a characterization of the logarithmic
differential forms with poles along A in terms of anti-invariant differential
forms. If W is a Coxeter group defined over the real numbers, then the
characterization provides a new method to find a basis for the module of
logarithmic differential forms out of basic invariants.

</DOC>
<DOC>
<DOCNO> 122965 </DOCNO>
Position-Space Description of the Cosmic Microwave Background and Its


  We suggest that the cosmic microwave background (CMB) temperature correlation
function C(theta) as a function of angle provides a direct connection between
experimental data and the fundamental cosmological quantities. The evolution of
inhomogeneities in the prerecombination universe is studied using their Green's
functions in position space. We find that a primordial adiabatic point
perturbation propagates as a sharp-edged spherical acoustic wave. Density
singularities at its wavefronts create a feature in the CMB correlation
function distinguished by a dip at theta ~ 1.2 deg. Characteristics of the
feature are sensitive to the values of cosmological parameters, in particular
to the total and the baryon densities.

</DOC>
<DOC>
<DOCNO> 10742 </DOCNO>
Mott transition of the f-electron system in the periodic Anderson model


  We show analytically that, under certain assumptions, the periodic Anderson
model and the Hubbard model become equivalent within the dynamical mean field
theory for quasiparticle weight Z -> 0. A scaling relation is derived which is
validated numerically using the numerical renormalization group at zero
temperature and quantum Monte Carlo simulations at finite temperatures. Our
results show that the f-electrons of the half-filled periodic Anderson model
with nearest neighbor hybridization get localized at a finite critical
interaction strength U_c}, also at zero temperature. This transition is
equivalent to the Mott-transition in the Hubbard model.

</DOC>
<DOC>
<DOCNO> 83139 </DOCNO>
Termination Proofs for Logic Programs with Tabling


  Tabled logic programming is receiving increasing attention in the Logic
Programming community. It avoids many of the shortcomings of SLD execution and
provides a more flexible and often extremely efficient execution mechanism for
logic programs. In particular, tabled execution of logic programs terminates
more often than execution based on SLD-resolution. In this article, we
introduce two notions of universal termination of logic programming with
Tabling: quasi-termination and (the stronger notion of) LG-termination. We
present sufficient conditions for these two notions of termination, namely
quasi-acceptability and LG-acceptability, and we show that these conditions are
also necessary in case the tabling is well-chosen. Starting from these
conditions, we give modular termination proofs, i.e., proofs capable of
combining termination proofs of separate programs to obtain termination proofs
of combined programs. Finally, in the presence of mode information, we state
sufficient conditions which form the basis for automatically proving
termination in a constraint-based way.

</DOC>
<DOC>
<DOCNO> 70645 </DOCNO>
/\_c+ - /\_c- production asymmetries in two component models


  Experiments on charm hadroproduction have shown a substantial difference in
the production of charm and anticharm hadrons. In this work we study /\_c+ and
/\_c- inclusive production in p-N interactions in the framework of two
component models. We show that the recombination two component model gives a
qualitatively and quantitatively good description of /\_c production while the
intrinsic charm model seems to be ruled out by recent experimental data from
the SELEX Collaboration.

</DOC>
<DOC>
<DOCNO> 122379 </DOCNO>
The first broad-band X-ray images and spectra of the 30 Doradus region


  We present the XMM-Newton first light image, taken in January 2000 with the
EPIC pn camera during the instrument's commissioning phase, when XMM-Newton was
pointing towards the Large Magellanic Cloud (LMC). The field is rich in
different kinds of X-ray sources: point sources, supernova remnants (SNRs) and
diffuse X-ray emission from LMC interstellar gas. The observations are of
unprecedented sensitivity, reaching a few 10^32 erg/s for point sources in the
LMC. We describe how these data sets were analysed and discuss some of the
spectroscopic results. For the SNR N157B the power law spectrum is clearly
steeper than previously determined from ROSAT and ASCA data. The existence of a
significant thermal component is evident and suggests that N157B is not a
Crab-like but a composite SNR. Most puzzling is the spectrum of the LMC hot
interstellar medium, which indicates a significant overabundance of Ne and Mg
of a few times solar.

</DOC>
<DOC>
<DOCNO> 151864 </DOCNO>
Codimension-Three Bundle Singularities in F-Theory


  We study new nonperturbative phenomena in N=1 heterotic string vacua
corresponding to pointlike bundle singularities in codimension three. These
degenerations result in new four-dimensional infrared physics characterized by
light solitonic states whose origin is explained in the dual F-theory model. We
also show that such phenomena appear generically in $E_7 \to E_6$ Higgsing and
describe in detail the corresponding bundle transition.

</DOC>
<DOC>
<DOCNO> 13138 </DOCNO>
Nonlinear limits to the information capacity of optical fiber


  The exponential growth in the rate at which information can be communicated
through an optical fiber is a key element in the so called information
revolution. However, like all exponential growth laws, there are physical
limits to be considered. The nonlinear nature of the propagation of light in
optical fiber has made these limits difficult to elucidate. Here we obtain
basic insights into the limits to the information capacity of an optical fiber
arising from these nonlinearities. The key simplification lies in relating the
nonlinear channel to a linear channel with multiplicative noise, for which we
are able to obtain analytical results. In fundamental distinction to the linear
additive noise case, the capacity does not grow indefinitely with increasing
signal power, but has a maximal value. The ideas presented here have broader
implications for other nonlinear information channels, such as those involved
in sensory transduction in neurobiology. These have been often examined using
additive noise linear channel models, and as we show here, nonlinearities can
change the picture qualitatively.

</DOC>
<DOC>
<DOCNO> 8648 </DOCNO>
Molecular Dynamics Simulations of Dynamic Force Microscopy: Applications


  Molecular dynamics simulations have been performed to understand true atomic
resolution, which has been observed on the Si(111)-7$\times$7 surface by
dynamic force microscopy in ultra high vacuum(UHV). Stable atomic-scale
contrast is reproduced in simulations at constant mean height above a critical
tip-sample separation when monitoring the interaction force between tip and
sample. Missing or additional adatoms can be recognized in such scans, although
they are less well resolved than native adatoms. The resonance frequency shift,
as well as arbitrary scans, e.g. at constant force can be computed from a
series of force-distance characteristics. By means of dynamic simulations we
show how energy losses induced by interaction with an oscillating tip can be
monitored and that they occur even in the non-contact range.

</DOC>
<DOC>
<DOCNO> 100537 </DOCNO>
Derived Hilbert schemes


  We construct the derived version of the Hilbert scheme parametrizing
subschemes in a given projective scheme X with given Hilbert polynomial h. This
is a dg-manifold (smooth dg-scheme) RHilb_h(X) which carries a natural family
of commutative (up to homotopy) dg-algebras, which over the usual Hilbert
scheme is just given by truncations of the homogeneous coordinate rings of
subschemes in X. In particular, RHilb_h(X) differs from RQuot_h(O_X), the
derived Quot scheme constructed in our previous paper (math.AG/9905174) which
carries only a family of A-infinity modules over the coordinate algebra of X.
  As an application, we construct the derived version of the moduli stack of
stable maps of (variable) algebraic curves to a given projective variety Y,
thus realizing the original suggestion of M. Kontsevich.

</DOC>
<DOC>
<DOCNO> 11000 </DOCNO>
Statistical Physics of Traffic Flow


  The modelling of traffic flow using methods and models from physics has a
long history. In recent years especially cellular automata models have allowed
for large-scale simulations of large traffic networks faster than real time. On
the other hand, these systems are interesting for physicists since they allow
to observe genuine nonequilibrium effects. Here the current status of cellular
automata models for traffic flow is reviewed with special emphasis on
nonequilibrium effects (e.g. phase transitions) induced by on- and off-ramps.

</DOC>
<DOC>
<DOCNO> 7880 </DOCNO>
Density-Matrix Renormalization-Group Analysis of Quantum Critical


  We present a simple method, combining the density-matrix
renormalization-group (DMRG) algorithm with finite-size scaling, which permits
the study of critical behavior in quantum spin chains. Spin moments and
dimerization are induced by boundary conditions at the chain ends and these
exhibit power-law decay at critical points. Results are presented for the
spin-1/2 Heisenberg antiferromagnet; an analytic calculation shows that
logarithmic corrections to scaling can sometimes be avoided. We also examine
the spin-1 chain at the critical point separating the Haldane gap and dimerized
phases. Exponents for the dimer-dimer and the spin-spin correlation functions
are consistent with results obtained from bosonization.

</DOC>
<DOC>
<DOCNO> 123060 </DOCNO>
Weak Lensing Constraints on Cluster Structural Parameters


  We study the reliability of dark matter (DM) profile determinations for rich
clusters of galaxies based on weak gravitational lensing measurements. We
consider three functional forms for the mass distribution: a softened
isothermal sphere (SIS), the Navarro, Frenk, & White model (NFW) and the
Klypin, Kravstov, Bullock, & Primack model (KKBP). A maximum likelihood
parametric method is developed and applied to simulated images of background
galaxies (z=2.0) lensed by clusters at z=0.2, 0.5, and 0.8. The images have
field size (~10 arcmin) and angular resolution (~0.5 arcsec) characteristic of
the new generation of 8-10 meter-class ground-based telescopes. The method
recovers the correct virial mass of the DM halo, M_{200}, to within ~10% at all
redshifts. The recovered values of \delta_c and r_s are only accurate to ~25%;
however, their correlated errors are such that greater accuracy is obtained for
the mass. Clusters with an SIS density profile are recognized by the method,
while NFW and KKBP clusters are recognized as not being SIS. The method does
not discriminate between NFW and KKBP profiles for clusters of a given mass,
because they are too similar in their outer regions. Strongly lensed arcs near
the cluster centers would be needed to distinguish NFW from KKBP.

</DOC>
<DOC>
<DOCNO> 39759 </DOCNO>
Use of Crystals for High Energy Photon Beam Linear Polarization


  The possibility to convert the photon beam linear polarization into circular
one at photon energies of hundreds GeV with the use of crystals is considered.
The energy and orientation dependencies of refractive indexes are investigated
in case of diamond, silicon and germanium crystal targets. To maximize the
values for figure of merit, the corresponding crystal optimal orientation
angles and thickness are found. The degree of circular polarization and
intensity of photon beam are estimated and possibility of experimental
realization is discussed.

</DOC>
<DOC>
<DOCNO> 68965 </DOCNO>
Parton Skewed Distributions in the Pion and Quark-Hadron Duality


  Applying arguments based on the operator product expansion for a three-point
correlator and relying on quark-hadron duality, we derive an expression for the
skewed (non-forward) parton distribution in the pion in the case of a
zero-skewedness parameter, {\cal F}^{\psi|\pi}_{\zeta=0}(X;t). We expect that
our result is relevant for moderately large momentum transfers 1 < t < 10
GeV^2. In addition, we construct a purely phenomenological factorized model for
the same quantity in close analogy to Radyushkin's model, originally proposed
for skewed distributions of quarks in the nucleon. Though the quark-hadron
duality approach supports theoretically the factorized model, the two models
exhibit a different behavior in the parton momentum fraction X at any fixed t.
The relevant process to distinguish between the two options seems to be the
WACS off the pion that measures (to leading t/s-order) the inverse moment
<X^{-1}> of the skewed distribution. Even after the inclusion of the first
order kinematic t/s-corrections, the predictions for the cross section \frac{d
\sigma}{d t}(s,t) at c.m.s. scattering angles \vartheta=30^{\circ} and
90^{\circ} differ by factors 3.5--3.9 and 2.9--7.5, respectively, so that a
discrimination appears possible.

</DOC>
<DOC>
<DOCNO> 67752 </DOCNO>
On gauge unification in Type I/I' models


  We discuss whether the (MSSM) unification of gauge couplings can be
accommodated in string theories with a low (TeV) string scale. This requires
either power law running of the couplings or logarithmic running extremely far
above the string scale. In both cases it is difficult to arrange for the
multiplet structure to give the MSSM result. For the case of power law running
there is also enhanced sensitivity to the spectrum at the unification scale.
For the case of logarithmic running there is a fine tuning problem associated
with the light closed string Kaluza Klein spectrum which requires gauge
mediated supersymmetry breaking on the ``visible'' brane with a dangerously low
scale of supersymmetry breaking. Evading these problems in low string scale
models requires a departure from the MSSM structure, which would imply that the
success of gauge unification in the MSSM is just an accident.

</DOC>
<DOC>
<DOCNO> 121886 </DOCNO>
Strings after D-term inflation: evolution and properties of chiral


  We motivate the study of chiral cosmic strings through a scenario of
structure formation which mixes D-term inflation and strings. We then discuss
some properties of chiral cosmic strings, and results regarding their evolution
and possible cosmological consequences are presented.

</DOC>
<DOC>
<DOCNO> 40385 </DOCNO>
Gravi-Burst: Super-GZK Cosmic Rays from Localized Gravity


  The flux of cosmic rays beyond the GZK cutoff ($\sim 10^{20}$ eV) may be
explained through their production by ultra high energy cosmic neutrinos,
annihilating on the relic neutrino background, in the vicinity of our galaxy.
This process is mediated through the production of a $Z$ boson at resonance,
and is generally known as the $Z$-Burst mechanism. We show that a similar
mechanism can also contribute to the super-GZK spectrum at even higher,
ultra-GZK energies, where the particles produced at resonance are the
Kaluza-Klein gravitons of weak scale mass and coupling from the Randall-Sundrum
(RS) hierarchy model of localized gravity model. We call this mechanism
Gravi-Burst. We discuss the parameter space of relevance to Gravi-Bursts, and
comment on the possibility of its contribution to the present and future
super-GZK cosmic ray data and place bounds on the RS model parameters. Under
certain assumptions about the energy spectrum of the primary neutrinos we find
that cosmic ray data could be potentially as powerful as the LHC in probing the
RS model.

</DOC>
<DOC>
<DOCNO> 99585 </DOCNO>
Conformal Geometry of Surfaces in the 4-Sphere and Quaternions


  This is the first comprehensive introduction to the authors' recent attempts
toward a better understanding of the global concepts behind spinor
representations of surfaces in 3-space. The important new aspect is a
quaternionic-valued function theory, whose "meromorphic functions" are
conformal maps into quaternions, which extends the classical complex function
theory on Riemann surfaces. The first results along these lines were presented
at the ICM 98 in Berlin. An important new invariant of the quaternionic
holomorphic theory is the Willmore energy. For quaternionic holomorphic curves
in the quaternionic projective line, i.e., the conformal 4-sphere, this energy
is the classical Willmore energy of conformal surfaces. Using these new
techniques, the article discusses the mean curvature sphere of conformal
surfaces in the 4-sphere, Willmore surfaces in the 4-sphere, Baecklund
tranformations of Willmore surfaces, super-conformal surfaces and twistor
projections, and a duality between Willmore surfaces in the 3-sphere and
minimal surfaces in hyperbolic 3-space. Finally, a new proof of Montiel's
recent classification of Willmore 2-spheres in the 4-sphere is given.

</DOC>
<DOC>
<DOCNO> 84724 </DOCNO>
Currents and Superpotentials in classical gauge theories: II. Global


  The conserved charges associated to gauge symmetries are defined at a
boundary component of space-time because the corresponding Noether current can
be rewritten on-shell as the divergence of a superpotential. However, the
latter is afflicted by ambiguities. Regge and Teitelboim found a procedure to
lift the arbitrariness in the Hamiltonian framework. An alternative covariant
formula was proposed by one of us for an arbitrary variation of the
superpotential, it depends only on the equations of motion and on the gauge
symmetry under consideration. Here we emphasize that in order to compute the
charges, it is enough to stay at a boundary of spacetime, without requiring any
hypothesis about the bulk or about other boundary components, so one may speak
of holographic charges. It is well known that the asymptotic symmetries that
lead to conserved charges are really defined at infinity, but the choice of
boundary conditions and surface terms in the action and in the charges is
usually determined through integration by parts whereas each component of the
boundary should be considered separately. We treat the example of gravity (for
any space-time dimension, with or without cosmological constant), formulated as
an Affine theory which is a natural generalization of the Palatini and
Cartan-Weyl (vielbein) first order formulations. We then show that the
superpotential associated to a Dirichlet boundary condition on the metric (the
one needed to treat asymptotically flat or AdS spacetimes) is the one proposed
by Katz, Bi\u{c}{\'a}k and Lynden-Bell and not that of Komar. We finally
discuss the KBL superpotential at null infinity.

</DOC>
<DOC>
<DOCNO> 71519 </DOCNO>
Skewed Parton Distributions


  Applications of perturbative QCD to deeply virtual Compton scattering and
hard exclusive electroproduction processes require a generalization of usual
parton distributions for the case when long-distance information is accumulated
in nonforward matrix elements of quark and gluon light-cone operators. We
describe two types of nonperturbative functions parametrizing such matrix
elements: double distributions F(x,y;t) and skewed distribution functions
 F_\zeta(X;t), discuss their properties, and basic uses in the QCD description
of hard exclusive processes.

</DOC>
<DOC>
<DOCNO> 13445 </DOCNO>
Identifying Business Sectors from Stock Price Fluctuations


  Firms having similar business activities are correlated. We analyze two
different cross-correlation matrices C constructed from (i) 30-min price
fluctuations of 1000 US stocks for the 2-year period 1994-95 and (ii) 1-day
price fluctuations of 422 US stocks for the 35-year period 1962-96. We find
that the eigenvectors of C corresponding to the largest eigenvalues allow us to
partition the set of all stocks into distinct subsets. These subsets are
similar to conventionally-identified business sectors, and are stable for
extended periods of time. Using a set of coupled stochastic differential
equations, we argue how correlations between stocks might arise. Finally, we
demonstrate that the sectors we identify are useful for the practical goal of
finding an investment which earns a given return without exposure to
unnecessary risk.

</DOC>
<DOC>
<DOCNO> 101960 </DOCNO>
How to relate the oscillator and Coulomb systems on spheres and


  We show that the oscillators on a sphere and pseudosphere are related, by the
so-called Bohlin transformation, with the Coulomb systems on the pseudosphere:
the even states of an oscillator yields the conventional Coulomb system on
pseudosphere, while the odd states yield the Coulomb system on pseudosphere in
the presence of magnetic flux tube generating half spin. In the higher
dimensions the oscillator and Coulomb(-like) systems are connected in the
similar way. In particular, applying the Kustaanheimo-Stiefel transformation to
the oscillators on sphere and pseudosphere, we obtained the preudospherical
generalization of MIC-Kepler problem describing three-dimensional charge-dyon
system.

</DOC>
<DOC>
<DOCNO> 151726 </DOCNO>
Lorentz Transformation and Light-Like Noncommutative SYM


  We show that combining the spatial noncommutative SYM limit and Lorentz
transformation, one can obtain a well-behaved light-like noncommutative SYM
limit. The light-like noncommutative SYM is unitary. When the boost velocity is
finite, the resulting theory with space-time noncommutativity is unitary as
well. The light-like noncommutative SYM limit can also be approached by
combining the noncommutative open string theory limit and Lorentz
transformation. Along this line, we obtain the supergravity dual for the
light-like noncommutative SYM, which is the same as the one acquired using a
different method. As a comparison, the supergravity duals for the ordinary SYM,
spatial noncommutative SYM and the noncommutative open string theories are
given as well, in an infinitely-boosted frame with finite momentum density,
which are the decoupling limits of bound states (Dp, W), (D($p-2$), W, Dp), and
(F1, W, Dp), respectively.

</DOC>
<DOC>
<DOCNO> 116284 </DOCNO>
Single-Pass Lazer Polarization of Ultrarelativistic Positrons


  The new method for producing of the polarized relativistic positrons is
suggested. A beam of unpolarized positrons accelerated up to a few GeV can be
polarized during a head-on collision with an intense circularly polarized lazer
wave. After a multiple Compton backscattering process the initial positrons may
lose a substantial part of its energy and, as consequence, may acquire the
significant longitudinal polarization. The simple formulas for the final
positron energy and polarization degree depended on the laser flash parameters
have been obtained. The comparison of efficiences for the suggested technique
and known ones is carried out. Some advantages of the new method were shown.

</DOC>
<DOC>
<DOCNO> 152593 </DOCNO>
Geometry of W-algebras from the affine Lie algebra point of view


  To classify the classical field theories with W-symmetry one has to classify
the symplectic leaves of the corresponding W-algebra, which are the
intersection of the defining constraint and the coadjoint orbit of the affine
Lie algebra if the W-algebra in question is obtained by reducing a WZNW model.
The fields that survive the reduction will obey non-linear Poisson bracket (or
commutator) relations in general. For example the Toda models are well-known
theories which possess such a non-linear W-symmetry and many features of these
models can only be understood if one investigates the reduction procedure. In
this paper we analyze the SL(n,R) case from which the so-called W_n-algebras
can be obtained. One advantage of the reduction viewpoint is that it gives a
constructive way to classify the symplectic leaves of the W-algebra which we
had done in the n=2 case which will correspond to the coadjoint orbits of the
Virasoro algebra and for n=3 which case gives rise to the Zamolodchikov
algebra. Our method in principle is capable of constructing explicit
representatives on each leaf. Another attractive feature of this approach is
the fact that the global nature of the W-transformations can be explicitly
described. The reduction method also enables one to determine the ``classical
highest weight (h. w.) states'' which are the stable minima of the energy on a
W-leaf. These are important as only to those leaves can a highest weight
representation space of the W-algebra be associated which contains a
``classical h. w. state''.

</DOC>
<DOC>
<DOCNO> 100100 </DOCNO>
Fermionic realisations of simple Lie algebras


  We study the representation ${\cal D}$ of a simple compact Lie algebra $\g$
of rank l constructed with the aid of the hermitian Dirac matrices of a (${\rm
dim} \g$)-dimensional euclidean space. The irreducible representations of $\g$
contained in ${\cal D}$ are found by providing a general construction on
suitable fermionic Fock spaces. We give full details not only for the simplest
odd and even cases, namely su(2) and su(3), but also for the next (${dim}
\g$)-even case of su(5). Our results are far reaching: they apply to any
$\g$-invariant quantum mechanical system containing ${\rm dim} \g$ fermions.
Another reason for undertaking this study is to examine the role of the
$\g$-invariant fermionic operators that naturally arise. These are given in
terms of products of an odd number of gamma matrices, and include, besides a
cubic operator, (l-1) fermionic scalars of higher order. The latter are
constructed from the Lie algebra cohomology cocycles, and must be considered to
be of theoretical significance similar to the cubic operator. In the (${\rm
dim} \g$)-even case, the product of all l operators turns out to be the
chirality operator $\gamma_q, q=({{\rm dim} \g+1})$.

</DOC>
<DOC>
<DOCNO> 150794 </DOCNO>
The type IIA NS5--Brane


  The kappa--invariant worldvolume action for the NS5--brane in a D=10 type IIA
supergravity background is obtained by carrying out the dimensional reduction
of the M5--brane action.

</DOC>
<DOC>
<DOCNO> 69058 </DOCNO>
Heavy quark potential in the static limit of QCD


  Following the procedure and motivations developed by Richardson, Buchmuller
and Tye, we derive the potential of static quarks consistent with both the
three-loop running of QCD coupling constant under the two-loop perturbative
matching of V and MS-bar schemes and the confinement regime at long distances.
Implications for the heavy quark masses as well as the quarkonium spectra and
leptonic widths are discussed.

</DOC>
<DOC>
<DOCNO> 83114 </DOCNO>
ACLP: Integrating Abduction and Constraint Solving


  ACLP is a system which combines abductive reasoning and constraint solving by
integrating the frameworks of Abductive Logic Programming (ALP) and Constraint
Logic Programming (CLP). It forms a general high-level knowledge representation
environment for abductive problems in Artificial Intelligence and other areas.
In ACLP, the task of abduction is supported and enhanced by its non-trivial
integration with constraint solving facilitating its application to complex
problems. The ACLP system is currently implemented on top of the CLP language
of ECLiPSe as a meta-interpreter exploiting its underlying constraint solver
for finite domains. It has been applied to the problems of planning and
scheduling in order to test its computational effectiveness compared with the
direct use of the (lower level) constraint solving framework of CLP on which it
is built. These experiments provide evidence that the abductive framework of
ACLP does not compromise significantly the computational efficiency of the
solutions. Other experiments show the natural ability of ACLP to accommodate
easily and in a robust way new or changing requirements of the original
problem.

</DOC>
<DOC>
<DOCNO> 99470 </DOCNO>
Classical Supersymmetric Mechanics


  We analyse a supersymmetric mechanical model derived from (1+1)-dimensional
field theory with Yukawa interaction, assuming that all physical variables take
their values in a Grassmann algebra B. Utilizing the symmetries of the model we
demonstrate how for a certain class of potentials the equations of motion can
be solved completely for any B. In a second approach we suppose that the
Grassmann algebra is finitely generated, decompose the dynamical variables into
real components and devise a layer-by-layer strategy to solve the equations of
motion for arbitrary potential. We examine the possible types of motion for
both bosonic and fermionic quantities and show how symmetries relate the former
to the latter in a geometrical way. In particular, we investigate oscillatory
motion, applying results of Floquet theory, in order to elucidate the role that
energy variations of the lower order quantities play in determining the
quantities of higher order in B.

</DOC>
<DOC>
<DOCNO> 11140 </DOCNO>
Ga-NMR local susceptibility of the kagome-based magnet


  We report a high-$T$ Ga-NMR study in the kagome-based antiferromagnetic
compound SrCr$_{9p}$Ga$_{12-9p}$O$_{19}$ ($.81\leq p\leq .96$), and present a
refined mean-field analysis of the high T local NMR susceptibility of Cr
frustrated moments. We find that the intralayer kagome coupling is $J=86(6)$ K,
and the interlayer coupling through non-kagome Cr moments is $J^{\prime
}=69(7)$ K. The $J^{\prime}/J=0.80(1)$ ratio confirms the common belief that
the frustrated entity is a pyrochlore slab.

</DOC>
<DOC>
<DOCNO> 117565 </DOCNO>
Extragalactic H2 and its variable relation to CO


  A steep metallicity dependence of the CO-to-H2 conversion factor X of the
form log X = 12.2 - 2.5 log[O]/[H], based on a sample of 20 (extra)galactic
determinations, is presented and discussed. The apparently less steep
dependence found from millimeter interferometer observations is explained
within the context of photon-dominated regions.

</DOC>
<DOC>
<DOCNO> 9763 </DOCNO>
Spin and charge excitations in incommensurate spin density waves


  Collective excitations both for spin- and charge-channels are investigated in
incommensurate spin density wave (or stripe) states on two-dimensional Hubbard
model. By random phase approximation, the dynamical susceptibility
\chi(q,\omega) is calculated for full range of (q,\omega) with including all
higher harmonics components. An intricate landscape of the spectra in
\chi(q,\omega) is obtained. We discuss the anisotropy of the dispersion cones
for spin wave excitations, and for the phason excitation related to the motion
of the stripe line. Inelastic neutron experiments on Cr and its alloys and
stripe states of underdoped cuprates are proposed.

</DOC>
<DOC>
<DOCNO> 178578 </DOCNO>
The $\pi$, $K^+$, and $K^0$ electromagnetic form factors


  The rainbow truncation of the quark Dyson-Schwinger equation is combined with
the ladder Bethe-Salpeter equation for the meson amplitudes and the dressed
quark-photon vertex in a self-consistent Poincar\'e-invariant study of the pion
and kaon electromagnetic form factors in impulse approximation. We demonstrate
explicitly that the current is conserved in this approach and that the obtained
results are independent of the momentum partitioning in the Bethe-Salpeter
amplitudes. With model gluon parameters previously fixed by the condensate, the
pion mass and decay constant, and the kaon mass, the charge radii and spacelike
form factors are found to be in good agreement with the experimental data.

</DOC>
<DOC>
<DOCNO> 152633 </DOCNO>
The Galilean Nature of V-duality for Noncommutative Open String and


  A V-duality conjecture for noncommutative open string theories (NCOS) that
result from decoupling D-branes in Lorentz-boost related backgrounds was put
forward recently in hep-th/0006013. The aim of this paper is to test the
Galilean nature of this conjecture in the gravity dual setup. We start with an
(F, D3) bound state Lorentz-boosted along one D3-brane direction perpendicular
to the F-string, and show that insisting a decoupled NCOS allows only
infinitesimal Lorentz boosts. In this way, it is shown that the V-duality
relates a family of NCOS by Galileo boosts. Starting with a Lorentz-boosted
(D1,D3) bound state, we show that a similar V-duality works for noncommutative
Yang-Mills (NCYM) theories as well. In addition, we deduce by a holography
argument that the running string tension, as a function of the energy scale,
for NCOS (or NCYM) remains unchanged under V-duality.

</DOC>
<DOC>
<DOCNO> 80989 </DOCNO>
Non-equilibrium field theory


  I discuss various topics in relativistic non-equilibrium field theory related
to high energy physics and cosmology. I focus on non-perturbative problems and
how they can be treated on the lattice.

</DOC>
<DOC>
<DOCNO> 122554 </DOCNO>
Shocks and sonic booms in the intracluster medium: X-ray shells and


  Motivated by hydrodynamic simulations, we discuss the X-ray appearance of
radio galaxies embedded in the intracluster medium (ICM) of a galaxy cluster.
We distinguish three regimes. In the early life of a powerful source, the
entire radio cocoon is expanding supersonically and hence drives a strong shock
into the ICM. Eventually, the sides of the cocoon become subsonic and the ICM
is disturbed by the sonic booms of the jet's working surface. In both of these
regimes, X-ray observations would find an X-ray shell. In the strong shock
regime, this shell will be hot and relatively thin. However, in the weak shock
(sonic-boom) regime, the shell will be approximately the same temperature as
the undisturbed ICM. If a cooling flow is present, the observed shell may even
be cooler than the undisturbed ICM due to the lifting of cooler material into
the shell from the inner (cooler) regions of the cluster. In the third and
final regime, the cocoon has collapsed and no well-defined X-ray shell will be
seen. We discuss ways of estimating the power and age of the source once its
regime of behavior has been determined.

</DOC>
<DOC>
<DOCNO> 85518 </DOCNO>
Embedding variables in finite dimensional models


  Global problems associated with the transformation from the Arnowitt, Deser
and Misner (ADM) to the Kucha\v{r} variables are studied. Two models are
considered: The Friedmann cosmology with scalar matter and the torus sector of
the 2+1 gravity. For the Friedmann model, the transformations to the Kucha\v{r}
description corresponding to three different popular time coordinates are shown
to exist on the whole ADM phase space, which becomes a proper subset of the
Kucha\v{r} phase spaces. The 2+1 gravity model is shown to admit a description
by embedding variables everywhere, even at the points with additional symmetry.
The transformation from the Kucha\v{r} to the ADM description is, however,
many-to-one there, and so the two descriptions are inequivalent for this model,
too. The most interesting result is that the new constraint surface is free
from the conical singularity and the new dynamical equations are linearization
stable. However, some residual pathology persists in the Kucha\v{r}
description.

</DOC>
<DOC>
<DOCNO> 12732 </DOCNO>
Pinning of the domain walls of the cluster spin-glass phase in LTT


  We compare the low frequency (~1 kHz) anelastic spectra of La_{2-x}Sr_xCuO_4
and La_{2-x}Ba_xCuO_4 at x = 0.03 and 0.06 in the temperature region where the
freezing into the cluster spin-glass (CSG) phase occurs and is accompanied by
an increase of the acoustic absorption. The dependence of the amplitude of the
anelastic relaxation on doping is explained in terms of movement of the domain
walls (DW) in the CSG phase between the Sr (Ba) pinning points. The LBCO sample
at x = 0.06 transforms into the LTT structure below 40 K and the amplitude of
the anelastic anomaly is 7 times smaller than expected, indicating pinning of
the DW which run parallel to the LTT modulation. Such DW can be identified with
the stripes of high hole density, and the present measurements show that they
are mobile between the Sr (Ba) pinning points down to few kelvin, but become
static in the presence of LTT modulation also far from the condition x = 1/8
for commensurability between stripe and lattice periodicities.

</DOC>
<DOC>
<DOCNO> 11611 </DOCNO>
Electron transport in nanotube--molecular wire hybrids


  We study contact effects on electron transport across a molecular wire
sandwiched between two semi-infinite (carbon) nanotube leads as a model for
nanoelectrodes. Employing the Landauer scattering matrix approach we find that
the conductance is very sensitive to parameters such as the coupling strength
and geometry of the contact. The conductance exhibits markedly different
behavior in the two limiting scenarios of single contact and multiple contacts
between the molecular wire and the nanotube interfacial atoms. In contrast to a
single contact the multiple-contact configuration acts as a filter selecting
single transport channels. It exhibits a scaling law for the conductance as a
function of coupling strength and tube diameter. We also observe an unusual
narrow-to-broad-to-narrow behavior of conductance resonances upon decreasing
the coupling.

</DOC>
<DOC>
<DOCNO> 121485 </DOCNO>
Wide band observations of the new X-ray burster SAX J1747.0-2853 during


  We report on our discovery and follow-up observations of the X-ray source SAX
J1747.0-2853 detected in outburst on 1998, March 10 with the BeppoSAX Wide
Field Cameras in the energy range 2-28 keV. The source is located about half
degree off the Galactic Nucleus. A total of 14 type-I X-ray bursts were
detected in Spring 1998, thus identifying the object as a likely low-mass X-ray
binary harboring a weakly magnetized neutron star. Evidence for photospheric
radius expansion is present in at least one of the observed bursts, leading to
an estimate of the source distance of about 9 kpc. We performed a follow-up
target of opportunity observation with the BeppoSAX Narrow Field Instruments on
March 23 for a total elapsed time of 72 ks. The source persistent luminosity
was 2.6x10^36 erg/s in the 2-10 keV energy range. The wide band spectral data
(1-200 keV) are consistent with a remarkable hard X-ray spectrum detected up to
150 keV, highly absorbed at low energies (Nh of the order of 10^23 cm^-2) and
with clear evidence for an absorption edge near 7 keV. A soft thermal component
is also observed, which can be described by single temperature blackbody
emission at about 0.6 keV.

</DOC>
<DOC>
<DOCNO> 69167 </DOCNO>
Hyperon Beta-Decay and Axial Charges of the Lambda in view of Strongly


  Within the collective coordinate approach to chiral soliton models we suggest
that breaking of SU(3) flavor symmetry mainly resides in the baryon
wave-functions while the charge operators maintain a symmetric structure.
Sizable symmetry breaking in the wave-functions is required to reproduce the
observed spacing in the spectrum of the (1/2)^+ baryons. The matrix elements of
the flavor symmetric charge operators nevertheless yield g_A/g_V ratios for
hyperon beta-decay which agree with the empirical data approximately as well as
the successful F&D parameterization of the Cabibbo scheme. Demanding the
strangeness component in the nucleon to vanish in the two flavor limit of the
model, determines the structure of the singlet axial charge operator and yields
the various quark flavor components of the axial charge of the \Lambda-hyperon.
The suggested picture gains support from calculations in a realistic model
using pion and vector meson degrees of freedom to build up the soliton.

</DOC>
<DOC>
<DOCNO> 10755 </DOCNO>
Systematic and Causal Corrections to the Coherent Potential


  The Dynamical Cluster Approximation (DCA) is modified to include disorder.
The DCA incorporates non-local corrections to local approximations such as the
Coherent Potential Approximation (CPA) by mapping the lattice problem with
disorder, and in the thermodynamic limit, to a self-consistently embedded
finite-sized cluster problem. It satisfies all of the characteristics of a
successful cluster approximation. It is causal, preserves the point-group and
translational symmetry of the original lattice, recovers the CPA when the
cluster size equals one, and becomes exact as $N_c\to\infty$. We use the DCA to
study the Anderson model with binary diagonal disorder. It restores sharp
features and band tailing in the density of states which reflect correlations
in the local environment of each site. While the DCA does not describe the
localization transition, it does describe precursor effects of localization.

</DOC>
<DOC>
<DOCNO> 9035 </DOCNO>
Renormalization group approach to nonextensive statistical mechanics


  We analyze a simple classical Hamiltonian system within the hypothesis of
renormalizability and isotropy that essentially led Maxwell to his ubiquitous
Gaussian distribution of velocities. We show that the equilibrium-like
power-law energy distribution emerging within nonextensive statistical
mechanics satisfies these hypothesis, in spite of not being factorizable. A
physically satisfactory renormalization group emerges in the $(q, T_q)$ space,
where q and $T_q$ respectively are the entropic index characterizing
nonextensivity, and an appropriate temperature. This scenario enables the
conjectural formulation of the one to be expected for d-dimensional systems
involving long-range interactions (e.g., a classical two-body potential
$\propto r^{-\alpha}$ with $0 \le \alpha/d \le 1$). As a corollary, we recover
a quite general expression for the classical principle of equipartition of
energy for arbitrary q.

</DOC>
<DOC>
<DOCNO> 69201 </DOCNO>
Zee-type Neutrino Mass Matrix and Bi-Maximal Mixing


  It is shown that the bi-maximal solution is the only possibility to reconcile
Zee-type neutrino mass matrix with three flavors to the current atmospheric and
solar neutrino experimental data. The mass of the lightest neutrino, which
consist mostly of $\nu_{\mu}$ and $\nu_{\tau}$, is $\simeq \Delta
m_{\odot}^2/(2\sqrt{\Delta m_{atm}^2})$. The related topics on Zee-type
neutrino mass matrix are also discussed.

</DOC>
<DOC>
<DOCNO> 70015 </DOCNO>
Off-Shell Effective Lagrangian for NRQCD and Heavy Quarks Effective


  derivation of the effective lagrangian for non-relativistic quantum
chromodynamics and the heavy quarks effective field theory is given. Our
calculation provides of a simple and systematic method of calculation of the
full off shell effective lagrangian at tree level including all the $1/m$
corrections.

</DOC>
<DOC>
<DOCNO> 68345 </DOCNO>
S and P-wave heavy-light mesons in lattice NRQCD


  The mass spectrum of S and P-wave mesons containing a single heavy quark is
computed in the quenched approximation, using NRQCD up to third order in the
inverse heavy quark mass expansion. Previous results found third order
contributions which are as large in magnitude as the total second order
contribution for the charmed S-wave spin splitting. The present work considers
variations such as anisotropic lattices, Landau link tadpole improvement, and a
highly-improved light quark action, and finds that the second order correction
to the charmed S-wave spin splitting is about 20% of the leading order
contribution, while the third order correction is about 20%(10%) for
D^*-D(D_s^*-D_s). Nonleading corrections are very small for the bottom meson
spectrum, and are statistically insignificant for the P-wave charmed masses.
The relative orderings among P-wave charmed and bottom mesons, and the sizes of
the mass splittings, are discussed in light of experimental data and existing
calculations.

</DOC>
<DOC>
<DOCNO> 13883 </DOCNO>
Disordered Dirac Fermions: the Marriage of Three Different Approaches


  We compare the critical multipoint correlation functions for two-dimensional
(massless) Dirac fermions in the presence of a random su(N) (non-Abelian) gauge
potential, obtained by three different methods. We critically reexamine
previous results obtained using the replica approach and in the limit of
infinite disorder strength and compare them to new results (presented here)
obtained using the supersymmetric approach to the N=2 case. We demonstrate that
this menage a trois of different approaches leads to identical results.
Remarkable relations between apparently different conformal field theories
(CFTs) are thereby obtained. We further establish a connection between the
random Dirac fermion problem and the c=-2 theory of dense polymers. The
presence of the c=-2 theory may be seen in all three different treatments of
the disorder.

</DOC>
<DOC>
<DOCNO> 150905 </DOCNO>
Nonnormalizable Zero Modes on BPS Junctions


  Using an exact solution as a concrete example, Nambu-Goldstone modes on the
BPS domain wall junction are worked out for N=1 supersymmetric theories in four
dimensions. Their wave functions extend along the wall to infinity (not
localized) and are not normalizable. It is argued that this feature is a
generic phenomenon of Nambu-Goldstone modes on domain wall junctions in the
bulk flat space in any dimensions. We formulate mode equations and show that
fermion and boson with the same mass come in pairs except massless modes which
can appear singly, in accordance with unitary representations of (1, 0)
supersymmetry.

</DOC>
<DOC>
<DOCNO> 121576 </DOCNO>
Solar Radiation and Asteroidal Motion


  Effects of solar wind and solar electromagnetic radiation on motion of
asteroids are discussed. The results complete the statements presented in
Vokrouhlick\'{y} and Milani (2000). As for the effect of electromagnetic
radiation, the complete equation of motion is presented to the first order in
$v/c$ -- the shape of asteroid (spherical body is explicitly presented) and
surface distribution of albedo should be taken into account. Optical quantities
must be calculated in proper frame of reference.

</DOC>
<DOC>
<DOCNO> 116923 </DOCNO>
A Low Charge Demonstration of Electron Pulse Compression for the CLIC RF


  The CLIC (Compact Linear Collider) RF power source is based on a new scheme
of electron pulse compression and bunch frequency multiplication using
injection by transverse RF deflectors into an isochronous ring. In this paper,
we describe the modifications needed in the present LEP Pre-Injector (LPI)
complex at CERN in order to perform a low-charge test of the scheme. The design
of the injector (including the new thermionic gun), of the modified linac, of
the matched injection line, and of the isochronous ring lattice, are presented.
The results of preliminary isochronicity measurements made on the present
installation are also discussed.

</DOC>
<DOC>
<DOCNO> 70796 </DOCNO>
Transverse momentum dependence in gluon distribution and fragmentation


  We investigate the twist two gluon distribution functions for spin 1/2
hadrons, emphasizing intrinsic transverse momentum of the gluons. These
functions are relevant in leading order in the inverse hard scale in scattering
processes such as inclusive leptoproduction or Drell-Yan scattering, or more
general in hard processes in which at least two hadrons are involved. They show
up in azimuthal asymmetries. For future estimates of such observables, we
discuss specific bounds on these functions.

</DOC>
<DOC>
<DOCNO> 150556 </DOCNO>
Superstring Theory on AdS_3 x G/H and Boundary N=3 Superconformal


  Superstrings propagating on backgrounds of the form AdS_3 x G/H are studied
using the coset CFT approach. We focus on seven dimensional cosets which have a
semiclassical limit, and which give rise to N=3 superconformal symmetry in the
dual CFT. This is realized for the two cases AdS_3 x SU(3)/U(1) and AdS_3 x
SO(5)/SO(3), for which we present an explicit construction. We also provide
sufficient conditions on a CFT background to enable a similar construction, and
comment on the geometrical interpretation of our results.

</DOC>
<DOC>
<DOCNO> 99851 </DOCNO>
Macaulay 2 and the geometry of schemes


  This tutorial illustrates how to use Grayson and Stillman's computer algebra
system, Macaulay2, to study schemes. The examples are taken from the homework
for an algebraic geometry class given at the University of California, Berkeley
in the fall of 1999. This graduate course was taught by the second author with
assistance for the first author. Our choice of problems follows the material in
Eisenbud and Harris' textbook, The Geometry of Schemes.

</DOC>
<DOC>
<DOCNO> 174537 </DOCNO>
Restoration of particle number as a good quantum number in BCS theory


  As shown in previous work, number projection can be carried out analytically
for states defined in a quasi-particle scheme when the states are expressed in
a coherent state representation. The wave functions of number-projected states
are well-known in the theory of orthogonal polynomials as Schur functions.
Moreover, the functions needed in pairing theory are a particularly simple
class of Schur functions that are easily constructed by means of recursion
relations. It is shown that complete sets of states can be projected from
corresponding quasi-particle states and that such states retain many of the
properties of the quasi-particle states from which they derive. It is also
shown that number projection can be used to construct a complete set of
orthogonal states classified by generalized seniority for any nucleus.

</DOC>
<DOC>
<DOCNO> 84266 </DOCNO>
Inertia in the Structure of Four-dimensional Space


  1. Following Rimman, Minkowski and Einstein, for the first time equations of
the inert filed in the covariant form are found geometrically. 2.In the
approximation of a weak field for the first time the Law of Inertia in a
material space (as opposed to the absolute space) is received. A consequence is
the formulation of Mach's principle. 3. Analogous to Einstein's expression for
the gravitational field, Compton's formula is received for the inert field. 4.
For the first time transcendental equations are received, one of the solutions
of which corresponds to the value of the magnetic charge by Dirack, or to the
constant of fine structure.

</DOC>
<DOC>
<DOCNO> 10384 </DOCNO>
Spectral function of transverse spin fluctuations in an antiferromagnet


  The spectral function of transverse spin fluctuations, including the
contributions from both the single-particle and the collective (magnon)
excitations in an antiferromagnet, is evaluated for the Hubbard model with NN
and NNN hoppings in the full U-range from weak coupling to strong coupling. For
the NN hopping model, the magnon excitations are dominant for U > 2.5 (d=2), so
that an effective spin description of the AF state holds down to a surprisingly
low U value. In the weak coupling limit the spectral function is suppressed at
low energies, as if due to an effective gap. NNN hopping t' leads to magnon
softening and also a significant increase in the low-energy spectral function
due to single-particle excitations. Evolution of the magnon spectrum with t' is
studied in the strong coupling limit, and the quantum spin- fluctuation
correction to sublattice magnetization in d=2 and the Neel temperature in d=3
are also evaluated.

</DOC>
<DOC>
<DOCNO> 100546 </DOCNO>
Special Lagrangian Cones


  We study special Lagrangian cones in $\C^n$ with isolated singularities. Our
main result constructs an infinite family of special Lagrangian cones in $\C^3$
each of which has a toroidal link. We obtain a detailed geometric description
of these tori. We prove a regularity result for special Lagrangian cones in
$\C^3$ with a spherical link -- any such cone must be a plane. We also
construct a one-parameter family of asymptotically conical special Lagrangian
submanifolds from any special Lagrangian cone.

</DOC>
<DOC>
<DOCNO> 10868 </DOCNO>
Two-dimensional dilute Bose gas in the normal phase


  We consider a two-dimensional dilute Bose gas above its superfluid transition
temperature. We show that the t-matrix approximation corresponds to the leading
set of diagrams in the dilute limit, provided the temperature is sufficiently
larger than the superfluid transition temperature. Within this approximation,
we give an explicit expression for the wave vector and frequency dependence of
the self-energy, and calculate the corrections to the chemical potential and
the effective mass arising from the interaction. We also argue that the
breakdown of the t-matrix approximation, which occurs upon lowering the
temperature, provides a simple criterion to estimate the superfluid critical
temperature for the two-dimensional dilute Bose gas. The critical temperature
identified by this criterion coincides with earlier results obtained by Popov
and by Fisher and Hohenberg using different methods. Extension of this
procedure to the three-dimensional case gives good agreement with recent Monte
Carlo data.

</DOC>
<DOC>
<DOCNO> 116885 </DOCNO>
The Diffraction Model and its Applicability for Wakefield Calculations


  The operation of a Free Electron Laser (FEL) in the ultraviolet or in the
X-ray regime requires the acceleration of electron bunches with an rms length
of 25 to 50 micro meters. The wakefields generated by these sub picosecond
bunches extend into the frequency range well beyond the threshold for Cooper
pair breakup (about 750 GHz) in superconducting niobium at 2 K. It is shown,
that the superconducting cavities can indeed be operated with 25 micro meter
bunches without suffering a breakdown of superconductivity (quench), however at
the price of a reduced quality factor and an increased heat transfer to the
superfluid helium bath. This was first shown by wakefield calculations based on
the diffraction model. In the meantime a more conventional method of computing
wake fields in the time domain by numerical methods was developed and used for
the wakefield calculations. Both methods lead to comparable results: the
operation of TESLA with 25 micro meter bunches is possible but leads to an
additional heat load due to the higher order modes (HOMs). Therefore HOM
dampers for these high frequencies are under construction. These dampers are
located in the beam pipes between the 9-cell cavities. So it is of interest, if
there are trapped modes in the cavity due to closed photon orbits. In this
paper we investigate the existence of trapped modes and the distribution of
heat load over the surface of the TESLA cavity by numerical photon tracking.

</DOC>
<DOC>
<DOCNO> 9178 </DOCNO>
Observation of harmonic generation and nonlinear coupling in the


  We report the observation of harmonic generation and strong nonlinear
coupling of two collective modes of a condensed gas of rubidium atoms. Using a
modified TOP trap we changed the trap anisotropy to a value where the frequency
of the m=0 high-lying mode corresponds to twice the frequency of the m=0
low-lying mode, thus leading to strong nonlinear coupling between these modes.
By changing the anisotropy of the trap and exciting the low-lying mode we
observed significant frequency shifts of this fundamental mode and also the
generation of its second harmonic.

</DOC>
<DOC>
<DOCNO> 67871 </DOCNO>
One-loop Kahler potential in non-renormalizable theories


  We consider a general d=4 N=1 globally supersymmetric lagrangian involving
chiral and vector superfields, with arbitrary superpotential, Kahler potential
and gauge kinetic function. We compute perturbative quantum corrections by
employing a component field approach that respects supersymmetry and background
gauge invariance. In particular, we obtain the full one-loop correction to the
Kahler potential in supersymmetric Landau gauge. Two derivations of this result
are described. The non-renormalization of the superpotential and the quadratic
correction to the Fayet-Iliopoulos terms are further checks of our
computations.

</DOC>
<DOC>
<DOCNO> 150618 </DOCNO>
Comments on Noncommutative Perturbative Dynamics


  We analyze further the IR singularities that appear in noncommutative field
theories on R^d. We argue that all IR singularities in nonplanar one loop
diagrams may be interpreted as arising from the tree level exchanges of new
light degrees of freedom, one coupling to each relevant operator. These
exchanges are reminiscent of closed string exchanges in the double twist
diagrams in open string theory. Some of these degrees of freedom are required
to have propagators that are inverse linear or logarithmic. We suggest that
these can be interpreted as free propagators in one or two extra dimensions
respectively. We also calculate some of the IR singular terms appearing at two
loops in noncommutative scalar field theories and find a complicated momentum
dependence which is more difficult to interpret.

</DOC>
<DOC>
<DOCNO> 101282 </DOCNO>
On the probabilistic rationale of I-divergence and J-divergence


  A probabilistic rationale for I-divergence minimization (relative entropy
maximization), non-parametric likelihood maximization and J-divergence
minimization (Jeffres' entropy maximization) criteria is provided.

</DOC>
<DOC>
<DOCNO> 179027 </DOCNO>
A Microscopic Picture of Strangeness Production at the SPS


  The microscopic origin of the strangeness enhancements observed in PbPb
collisions at the SPS is studied by testing the effects of three mechanisms.
First, the junction processes found in the HIJING/BBbar event generator are
reviewed showing that they can account for only part of the observed hyperon
enhancements. Second, the efficient final state chemical changing processes
(e.g. Lambda + K -> Xi + pi) are included by adding the General Cascade Program
(GCP) to HIJING/BBbar. While these processes are shown to further enhance
multistrange baryon production, HIJING/BBbar+GCP is still unable to fully
describe either the large hyperon yields or the increasing K+/pi+ ratio.
Finally, the addition of transient field fluctuations or ropes to
HIJING/BBbar+GCP is shown to be needed to account for the large hyperon yields
and for the behavior of the K+/pi+ ratio.

</DOC>
<DOC>
<DOCNO> 178478 </DOCNO>
Pairing correlation involving the continuum states


  The Hartree-Fock-Bogoliubov equation for the ground states of even-even
atomic nuclei is solved using the canonical representation in the coordinate
space for zero range interactions like the Skyrme force. The gradient method is
improved for faster convergence to the solutions under constraint of
orthogonality between canonical orbitals. Necessity of the cut-off of the
pairing interaction is shown even when the number of the canonical orbitals are
restricted. A repulsive dependence of the interaction on the pairing density is
introduced as an implementation of the cut-off which leaves the HFB super
matrix state-independent.

</DOC>
<DOC>
<DOCNO> 70573 </DOCNO>
The MSSM prediction for W+/- H-/+ production by gluon fusion


  We discuss the associated W+/- H-/+ production in p p collision for the Large
Hadron Collider. A complete one-loop calculation of the loop-induced subprocess
g g -> W+/- H-/+ is presented in the framework of the Minimal Supersymmetric
Standard Model (MSSM), and the possible enhancement of the hadronic cross
section is investigated under the constraint from the squark direct-search
results and the low-energy precision data. Because of the large destructive
interplay in the quark-loop contributions between triangle-type and box-type
diagrams, the squark-loop contributions turn out to be comparable with the
quark-loop ones. In particular, the hadronic cross section via gluon fusion can
be extensively enhanced by squark-pair threshold effects in the box-type
diagrams, so that it can be as large as the hadronic cross section via the b
b-bar -> W+/- H-/+ subprocess which appears at tree level.

</DOC>
<DOC>
<DOCNO> 9102 </DOCNO>
How to create Alice string (half-quantum vortex) in a vector


  We suggest a procedure how to prepare the vortex with N=1/2 winding number --
the counterpart of the Alice string -- in a Bose--Einstein condensate with
hyperfine spin F=1. Other possible vortices in Bose-condensates are also
discussed.

</DOC>
<DOC>
<DOCNO> 85568 </DOCNO>
Toward a Midisuperspace Quantization of LeMaitre-Tolman-Bondi Collapse


  LeMa\^\i tre-Tolman-Bondi models of spherical dust collapse have been used
and continue to be used extensively to study various stellar collapse
scenarios. It is by now well-known that these models lead to the formation of
black holes and naked singularities from regular initial data. The final
outcome of the collapse, particularly in the event of naked singularity
formation, depends very heavily on quantum effects during the final stages.
These quantum effects cannot generally be treated semi-classically as quantum
fluctuations of the gravitational field are expected to dominate before the
final state is reached. We present a canonical reduction of LeMa\^\i
tre-Tolman-Bondi space-times describing the marginally bound collapse of
inhomogeneous dust, in which the physical radius, $R$, the proper time of the
collapsing dust, $\tau$, and the mass function, $F$, are the canonical
coordinates, $R(r)$, $\tau(r)$ and $F(r)$ on the phase space. Dirac's
constraint quantization leads to a simple functional (Wheeler-DeWitt) equation.
The equation is solved and the solution can be employed to study some of the
effects of quantum gravity during gravitational collapse with different initial
conditions.

</DOC>
<DOC>
<DOCNO> 70397 </DOCNO>
Brane World Cosmology Without the Z_2 Symmetry


  The Friedmann equation for a positive tension brane situated between two bulk
spacetimes that posses the same 5D cosmological constant, but which does not
posses a Z_2 symmetry of the metric itself is derived, and the possible effects
of dropping the Z_2 symmetry on the expansion of our Universe are examined;
cosmological constraints are discussed. The global solutions for the metric in
the infinite extra dimension case are found and comparison with the symmetric
case is made. We show that any brane world senario of this type must revert to
a Z_2 symmetric form at late times, and hence rule out certain proposed
scenarios.

</DOC>
<DOC>
<DOCNO> 117812 </DOCNO>
ISO observational campaign of the BL Lac object PKS 2155-304


  The BL Lacertae object PKS 2155-304 was observed by the Infrared Space
Observatory in May and June 1996, during a multiwavelength campaign. These are
the first observations in the mid- and far-infrared bands since IRAS. In the
observing period, the source showed no detectable time variability at 4.0,
14.3, 60 and 90 micron. The spectrum from 2.8 to 100 micron is well fitted by a
single power law with energy spectral index alpha = 0.4, intermediate between
the flatter radio spectrum and the steeper simultaneous optical spectrum. The
overall infrared to X-ray spectral energy distribution can be well explained by
optically thin synchrotron emission, with negligible contributions from thermal
sources. We also show that the host galaxy flux is negligible in this spectral
range.

</DOC>
<DOC>
<DOCNO> 70975 </DOCNO>
Hadron Correlators in the Deconfined Phase


  Temporal meson correlators and their spectral functions are calculated in the
deconfined phase using the hard thermal loop resummation technique. The
spectral functions exhibit strong medium effects coming from the hard thermal
loop approximation for the quark propagator. The correlators, on the other
hand, do not differ significantly from free correlators, for which bare quark
propagators are used. This is in contrast to lattice calculations showing a
clear deviation from the free correlations functions.

</DOC>
<DOC>
<DOCNO> 152216 </DOCNO>
Running couplings and triviality of field theories on non-commutative


  We examine the issue of renormalizability of asymptotically free field
theories on non-commutative spaces. As an example, we solve the non-commutative
O(N) invariant Gross-Neveu model at large N. On commutative space this is a
renormalizable model with non-trivial interactions. On the noncommutative
space, if we take the translation invariant ground state, we find that the
model is non-renormalizable. Removing the ultraviolet cutoff yields a trivial
non-interacting theory.

</DOC>
<DOC>
<DOCNO> 69908 </DOCNO>
Stellar production rates of carbon and its abundance in the universe


  The bulk of the carbon in our universe is produced in the triple-alpha
process in helium-burning red giant stars. We calculated the change of the
triple-alpha reaction rate in a microscopic 12-nucleon model of the C-12
nucleus and looked for the effects of minimal variations of the strengths of
the underlying interactions. Stellar model calculations were performed with the
alternative reaction rates. Here, we show that outside a narrow window of 0.5
and 4% of the values of the strong and Coulomb forces, respectively, the
stellar production of carbon or oxygen is reduced by factors of 30 to 1000.

</DOC>
<DOC>
<DOCNO> 68442 </DOCNO>
One Interesting New Sum Rule Extending Bjorken's to order {1/m_Q}


  We explicitly check quark-hadron duality to order $(m_b-m_c)\Lambda/m_b^2$
for $b \to c l\nu$ decays in the limit $m_b-m_c \ll m_b$ including ground state
and orbitally excited hadrons. Duality occurs thanks to a new sum rule which
expresses the subleading HQET form factor $\xi_3$ or, in other notations,
 $a_+^{(1)}$ in terms of the infinite mass limit form factors and some level
splittings. We also demonstrate the sum rule, which is not restricted to the
condition $m_b-m_c \ll m_b$, applying OPE to the longitudinal axial component
of the hadronic tensor without neglecting the $1/m_b$ subleading contributions
to the form factors. We argue that this method should produce a new class of
sum rules, depending on the current, beyond Bjorken, Voloshin and the known
tower of higher moments. Applying OPE to the vector currents we find another
derivation of the Voloshin sum rule. From independent results on $\xi_3$ we
derive a sum rule which involves only the $\tau_{1/2}^{(n)}$ and
$\tau_{3/2}^{(n)}$ form factors and the corresponding level splittings. The
latter strongly supports a theoretical evidence that the $B$ semileptonic decay
into narrow orbitally-excited resonances dominates over the decay into the
broad ones, in apparent contradiction with some recent experiments. We discuss
this issue.

</DOC>
<DOC>
<DOCNO> 12368 </DOCNO>
Effect of the accelerating growth of communications networks on their


  Motivated by data on the evolution of the Internet and World Wide Web we
consider scenarios of self-organization of the nonlinearly growing networks
into free-scale structures. We find that the accelerating growth of the
networks establishes their structure. For the growing networks with
preferential linking and increasing density of links, two scenarios are
possible. In one of them, the value of the exponent $\gamma$ of the
connectivity distribution is between 3/2 and 2. In the other, $\gamma>2$ and
the distribution is necessarily non-stationary.

</DOC>
<DOC>
<DOCNO> 118994 </DOCNO>
Temporal variations of the rotation rate in the solar interior


  The temporal variations of the rotation rate in the solar interior are
studied using frequency splittings from Global Oscillations Network Group
(GONG) data obtained during the period 1995-99. We find alternating latitudinal
bands of faster and slower rotation which appear to move towards the equator
with time - similar to the torsional oscillations seen at the solar surface.
This flow pattern appears to persist to a depth of about 0.1R_sun and in this
region its magnitude is well correlated with solar activity indices. We do not
find any periodic or systematic changes in the rotation rate near the base of
the convection zone.

</DOC>
<DOC>
<DOCNO> 70861 </DOCNO>
Color Octet Contribution in Exclusive P-Wave Charmonium Decay


  Recent advances in our understanding of the higher-wave quarkonia have
generated much interests in quarkonium physics. However most are devoted to
inclusive decays and productions. Experimental data of several two-body
exclusive decay channels of P-wave charmonia such as \pi \pi and p \bar p are
available and some have recently been re-measured by the BES collaboration. It
is not clear from the outset that color octet is needed for these exclusive
channels. Indeed only color singlet has been used in the past and reasonable
agreement with data was found. Contrary to these old results, we provide
theoretical arguments for the inclusion of color octet and perform explicit
calculations to back this up.

</DOC>
<DOC>
<DOCNO> 120970 </DOCNO>
ISO-SWS calibration and the accurate modelling of cool-star atmospheres:


  A detailed spectroscopic study of the ISO-SWS data of the red giant Alpha Tau
is presented, which enables not only the accurate determination of the stellar
parameters of Alpha Tau, but also serves as a critical review of the ISO-SWS
calibration.
  This study is situated in a broader context of an iterative process in which
both accurate observations of stellar templates and cool star atmosphere models
are involved to improve the ISO-SWS calibration process as well as the
theoretical modelling of stellar atmospheres. Therefore a sample of cool stars,
covering the whole A0 -- M8 spectral classification, has been observed in order
to disentangle calibration problems and problems in generating the theoretical
models and corresponding synthetic spectrum.
  By using stellar parameters found in the literature large discrepancies were
seen between the ISO-SWS data and the generated synthetic spectrum of Alpha
Tau. A study of the influence of various stellar parameters on the theoretical
models and synthetic spectra, in conjunction with the Kolmogorov-Smirnov test
to evaluate objectively the goodness-of-fit, enables us to pin down the stellar
parameters with a high accuracy: Teff = 3850 +/- 70 K, log g = 1.50 +/- 0.15, M
= 2.3 +/- 0.8 Msun, z = -0.15 +/- 0.20 dex, microturbulence = 1.7 +/- 0.3 km/s,
12C/13C= 10 +/- 1, abundance of C = 8.35 +/- 0.20 dex, abundance of N= 8.35 +/-
0.25 dex, abundance of O = 8.83 +/- 0.15 dex and the angular diameter is 20.77
+/- 0.83 mas. These atmospheric parameters were then compared with the results
provided by other authors using other methods and/or spectra.

</DOC>
<DOC>
<DOCNO> 14081 </DOCNO>
Shot Noise in Mesoscopic Quantum Systems


  We examine critically the idea that fractional charges may carry electrical
current in a conductor, much as do the normal electrons in a metallic Fermi
liquid. We explore a range of issues that have gained the status of
indispensability for analyzing conductance and shot noise in fractionally
charged systems. For these fundamental transport problems, however, a truly
microscopic understanding is not yet in sight.

</DOC>
<DOC>
<DOCNO> 122266 </DOCNO>
Infrared Emission from Interstellar Dust. II. The Diffuse Interstellar


  We present a quantitative model for the infrared emission from dust in the
diffuse interstellar medium. The model consists of a mixture of amorphous
silicate grains and carbonaceous grains, each with a wide size distribution
ranging from molecules containing tens of atoms to large grains > 1 um in
diameter. We assume that the carbonaceous grains have polycyclic aromatic
hydrocarbon (PAH)-like properties at very small sizes, and graphitic properties
for radii a > 50 A. On the basis of recent laboratory studies and guided by
astronomical observations, we propose "astronomical" absorption cross sections
for use in modeling neutral and ionized PAHs from the far ultraviolet to the
far infrared. We also propose modifications to the far-infrared emissivity of
"astronomical silicate". We calculate energy distribution functions for small
grains undergoing "temperature spikes" due to stochastic absorption of
starlight photons, using realistic heat capacities and optical properties.
Using a grain size distribution consistent with the observed interstellar
extinction, we are able to reproduce the near-IR to submillimeter emission
spectrum of the diffuse interstellar medium, including the PAH emission
features at 3.3, 6.2, 7.7, 8.6, and 11.3um. The model is compared with the
observed emission at high Galactic latitudes as well as in the Galactic plane,
as measured by COBE and IRTS. We calculate infrared emission spectra for our
dust model heated by a range of starlight intensities, and we provide tabulated
dust opacities (extended tables available at
http://www.astro.princeton.edu/~draine/dust/dustmix.html)

</DOC>
<DOC>
<DOCNO> 178852 </DOCNO>
Semiclassical Calculation of Shell Effects in Deformed Nuclei


  We summarize recent work in which the shell effect, which causes the onset of
the mass asymmetry in nuclear fission, could be explained semiclassically in
the framework of the periodic orbit theory. We also present new results for the
inclusion of a spin-orbit interaction in the semiclassical calculation of the
level density.

</DOC>
<DOC>
<DOCNO> 150316 </DOCNO>
A Two-loop Test of Buscher's T-duality I


  We study the two loop quantum equivalence of sigma models related by
Buscher's T-duality transformation. The computation of the two loop
perturbative free energy density is performed in the case of a certain
deformation of the SU(2) principal sigma model, and its T-dual, using
dimensional regularization and the geometric sigma model perturbation theory.
We obtain agreement between the free energy density expressions of the two
models.

</DOC>
<DOC>
<DOCNO> 120302 </DOCNO>
Chandra constraints on the thermal conduction in the intracluster plasma


  In this Letter, we use the recent Chandra observation of A2142 reported by
Markevitch et al. to put constraints on thermal conduction in the intracluster
plasma. We show that the observed sharp temperature gradient requires that
classical conductivity has to be reduced at least by a factor of between 250
and 2500. The result provides a direct constraint on an important physical
process relevant to the gas in the cores of clusters of galaxies.

</DOC>
<DOC>
<DOCNO> 70835 </DOCNO>
The Topological AC and HMW Effects, and the Dual Current in 2+1


  We study the Aharonov-Casher (AC) effect and the related He-McKellar-Wilkens
(HMW) effect in 2+1 dimensions. In this restricted space these effects are the
result of the interaction of the electromagnetic field tensor with the dual of
a current. Transferring the dual operation from the current to the field tensor
shows that this interaction may be reinterpreted as due to the interaction of
an effective vector potential and a current, and the AC and HMW effects
follow immediately. A general proof of this for particles with an arbitrary
spin is provided.
  The restriction to 2+1 dimensions, with this interpretation, provides a
unified way of treating the AC and HMW effects for an arbitrary spin. Perhaps
more interestingly the treatment shows that a spin-0 particle can show AC and
HMW effects, although it has no magnetic or electric dipole moment in the usual
sense.

</DOC>
<DOC>
<DOCNO> 71320 </DOCNO>
Lambda polarization in unpolarized hadron reactions


  The transverse polarization observed in the inclusive production of Lambda
hyperons in the high energy collisions of unpolarized hadrons is tackled by
considering a new set of spin and kT dependent quark fragmentation functions.
Simple phenomenological expressions for these new ``polarizing fragmentation
functions'' are obtained by a fit of the data on Lambda's and Lambdabar's
produced in p-N processes.

</DOC>
<DOC>
<DOCNO> 151872 </DOCNO>
Noncompact Gepner Models for Type II Strings on a Conifold and an ALE


  We construct modular invariant partition functions for type II strings on a
conifold and a singular Eguchi-Hanson instanton by means of the SL(2,R)/U(1)
version of Gepner models. In the conifold case, we find an extra massless
hypermultiplet in the IIB spectrum and argue that it may be identified as a
soliton. In the Eguchi-Hanson case, our formula is new and different from the
earlier result, in particular does not contain graviton. The lightest IIB
fields are combined into a six-dimensional (2,0) tensor multiplet with a
negative mass square. We give an interpretation to it as a doubleton-like mode.

</DOC>
<DOC>
<DOCNO> 9979 </DOCNO>
A brief introduction to Luttinger liquids


  I give a brief introduction to Luttinger liquids. Luttinger liquids are
paramagnetic one-dimensional metals without Landau quasi-particle excitations.
The elementary excitations are collective charge and spin modes, leading to
charge-spin separation. Correlation functions exhibit power-law behavior. All
physical properties can be calculated, e.g. by bosonization, and depend on
three parameters only: the renormalized coupling constant $K_{\rho}$, and the
charge and spin velocities. I also discuss the stability of Luttinger liquids
with respect to temperature, interchain coupling, lattice effects and phonons,
and list important open problems.

</DOC>
<DOC>
<DOCNO> 11618 </DOCNO>
Tunneling between coupled Luttinger liquids


  We consider the problem of tunneling between spinless 1D Luttinger liquid
chains. We show how to map the problem onto the 4-state chiral clock model
together with a free boson for the total charge mode. We use a variety of
results, some of them exact, from the integrable chiral Potts model and the
study of commensurate/incommensurate transitions to deduce the physics of
coupled Luttinger liquids. For those intrachain interaction strengths for which
interchain tunneling is relevant, we find that it can lead to the formation of
symmetric and antisymmetric bands with split Fermi surfaces, depending on the
relative strengths of interchain tunneling and interchain interactions. With
split Fermi surfaces, the tunneling is coherent. It is not possible to have two
gapless Fermi surfaces with the same Fermi momentum when interchain tunneling
is relevant. However, interchain interactions can drive the formation of a gap,
in which case interchain transport will be incoherent. We comment on the
possible relevance of our results to c-axis transport in high-T_c
superconductors.

</DOC>
<DOC>
<DOCNO> 120256 </DOCNO>
A simluated TCDM cosmology cluster catalogue: the NFW profile and the


  We have extracted over 400 clusters, covering more than 2 decades in mass,
from three simulations of the TCDM cosmology. This represents the largest,
uniform catalogue of simulated clusters ever produced. The clusters exhibit a
wide variety of density-profiles. Only a minority are well-fit in their outer
regions by the widely used density profile of Navarro, Frenk & White (1977).
Others have steeper outer density profiles, show sharp breaks in their density
profiles, or have significant substructure. If we force a fit to the NFW
profile, then the best-fit concentrations decline with increasing mass, but
this is driven primarily by an increase in substructure as one moves to higher
masses. The measured temperature-mass relations for properties measured within
a sphere enclosing a fixed overdensity all follow the self-similar form,
T\propto M^{2/3}, however the normalisation is lower than in observed clusters.
The temperature-mass relations for properties measured within a fixed physical
radius are significantly steeper then this. Both can be accurately predicted
using the NFW model.

</DOC>
<DOC>
<DOCNO> 152631 </DOCNO>
N=2 and N=4 supersymmetric Born-Infeld theories from nonlinear


  Starting from nonlinear realizations of the partially broken central-charge
extended N=4 and N=8 Poincar\'e supersymmetries in D=4, we derive the
superfield equations of N=2 and N=4 Born-Infeld theories. The basic objects are
the bosonic Goldstone N=2 and N=4 superfields associated with the central
charge generators. By construction, the equations are manifestly N=2 and N=4
supersymmetric and enjoy covariance under another nonlinearly realized half of
the original supersymmetries. They provide a manifestly worldvolume
supersymmetric static-gauge description of D3-branes in D=6 and D=10. For the
N=2 case we find, to lowest orders, the equivalence transformation to the
standard N=2 Maxwell superfield strength and restore, up to the sixth order,
the off-shell N=2 Born-Infeld action with the second hidden N=2 supersymmetry.

</DOC>
<DOC>
<DOCNO> 7815 </DOCNO>
High-pressure Raman study of L-alanine crystal


  Pressure-dependent Raman scattering studies in the range 0.0 -- 32 kbar were
carried out in L-alanine in order to investigate its external mode phonon
spectra in relation to the phase transitions in the crystal. A careful analysis
of the spectra shows that the low-energy Raman modes exhibit variation both in
frequency and in intensity and between 26 and 28 kbar it is observed a
splitting of a external mode, indicating that the D_2 normal phase undergoes a
transition. Pressure coefficients for external modes are also given.

</DOC>
<DOC>
<DOCNO> 85411 </DOCNO>
Ever-expanding, Isotropizing, Quadratic Cosmologies


  We consider some aspects of the global evolution problem of Hamiltonian
homogeneous, anisotropic cosmologies derived from a purely quadratic action
functional of the scalar curvature. We show that models can isotropize in the
positive asymptotic direction and that quadratic diagonal Bianchi IX models do
not recollapse and may be regular initially. Although the global existence and
isotropization results we prove hold quite generally, they are applied to
specific Bianchi models in an attempt to describe how certain dynamical
properties uncommon to the general relativity case, become generic features of
these quadratic universes. The question of integrability of the models is also
considered. Our results point to the fact that the more general models are not
integrable in the sense of Painlev\'e and for the Bianchi IX case this may be
connected to the validity of a BKL oscillatory picture on approach to the
singularity in sharp contrast with other higher order gravity theories that
contain an Einstein term and show a monotonic evolution towards the initial
singularity.

</DOC>
<DOC>
<DOCNO> 99806 </DOCNO>
Computer Algebra and Algebraic Geometry - Achievements and Perspectives


  In this survey I should like to introduce some concepts of algebraic geometry
and try to demonstrate the fruitful interaction between algebraic geometry and
computer algebra and, more generally, between mathematics and computer science.
One of the aims of this article is to show, by means of examples, the
usefulness of computer algebra to mathematical research.

</DOC>
<DOC>
<DOCNO> 100955 </DOCNO>
Cauchy Inequality and the Space of Measured Laminations


  We establish a Cauchy type inequality for the geometric intersection number
between two 1-dimensional submanifolds in a surface. Some of the basic results
in Thurston's theory of measured laminations on surfaces are derived from the
Cauchy inequality.

</DOC>
<DOC>
<DOCNO> 152104 </DOCNO>
A Note on Noncommutative and False Noncommutative spaces


  We show that the algebra of functions on noncommutative space allows two
different representations. One is describing the genuine noncommutative space,
while another one can be rewritten in commutative form by a redefinition of
generators.

</DOC>
<DOC>
<DOCNO> 10149 </DOCNO>
Tiles and colors


  Tiling models are classical statistical models in which different geometric
shapes, the tiles, are packed together such that they cover space completely.
In this paper we discuss a class of two-dimensional tiling models in which the
tiles are rectangles and isosceles triangles. Some of these models have been
solved recently by means of Bethe Ansatz. We discuss the question why only
these models in a larger family are solvable, and we search for the Yang-Baxter
structure behind their integrablity. In this quest we find the Bethe Ansatz
solution of the problem of coloring the edges of the square lattice in four
colors, such that edges of the same color never meet in the same vertex.

</DOC>
<DOC>
<DOCNO> 9481 </DOCNO>
Sum Rule for the Optical Absorption of an Interacting Many-Polaron Gas


  A sum rule for the first frequency moment of the optical absorption of a
many-polaron system is derived, taking into account many-body effects in the
system of constituent charge carriers of the many-polaron system. In our
expression for the sum rule, the electron-phonon coupling and the many-body
effects in the electron (or hole) system formally decouple, so that the
many-body effects can be treated to the desired level of approximation by the
choice of the dynamical structure factor of the electron (hole) gas. We
calculate correction factors to take into account both low and high
experimental cutoff frequencies.

</DOC>
<DOC>
<DOCNO> 10458 </DOCNO>
Reply to the comment of Chudnovsky&Garanin on "Spin relaxation in


  Reply to the comment of E.M. Chudnovsky and D.A. Garanin on Europhys. Lett.
46, 692 (1999).

</DOC>
<DOC>
<DOCNO> 9804 </DOCNO>
Electronic and Magnetic Properties of Febr2


  Electronic and magnetic (e-m) properties of FeBr2 have been surprisingly well
described as originating from the Fe2+ ions and their fine electronic
structure. The fine electronic structure have been evaluated taking into
account the spin-orbit (s-o) coupling, crystal-field and inter-site
spin-dependent interactions. The required magnetic doublet ground state with an
excited singlet at D=2.8 meV results from the trigonal distortion. This effect
of the trigonal distortion and a large magnetic moment of iron, of 4.4 mB, can
be theoretically derived provided the s-o coupling is correctly taking into
account. The obtained good agreement with experimental data indicates on
extremaly strong correlations of the six 3d electrons in the Fe2+ ion yielding
their full localization and the insulating state. These calculations show that
for the meaningful analysis of e-m properties of FeBr2 the spin-orbit coupling
is essentially important and that the orbital moment (0.74 mB) is largely
unquenched (by the off-cubic trigonal distortion in the presence of the
spin-orbit coupling).

</DOC>
<DOC>
<DOCNO> 118022 </DOCNO>
Identification of a nearby stellar association in the Hipparcos catalog:


  The TW Hydrae Association (~55 pc from Earth) is the nearest known region of
recent star formation. Based primarily on the Hipparcos catalog, we have now
identified a group of 9 or 10 co-moving star systems at a common distance (~45
pc) from Earth that appear to comprise another, somewhat older, association
(``the Tucanae Association''). Together with ages and motions recently
determined for some nearby field stars, the existence of the Tucanae and TW
Hydrae Associations suggests that the Sun is now close to a region that was the
site of substantial star formation only 10-40 million years ago. The TW Hydrae
Association represents a final chapter in the local star formation history.

</DOC>
<DOC>
<DOCNO> 152550 </DOCNO>
World Sheet Logarithmic CFT in AdS Strings, Ghost-Matter Mixing and


  We discuss several closely related concepts in the NSR formulation of
superstring theory. We demonstrated that recently proposed NSR model for
superstrings on $AdS_5 \times S^5$ is described by the world-sheet logarithmic
conformal field theory (LCFT). The origin of LCFT on a world-sheet is closely
connected to the matter-ghost mixing in the structure of a brane-like vortex
operators. We suggest a dynamical origin of M theory as a string theory with an
extra dimension given by bosonised superconformal ghosts.

</DOC>
<DOC>
<DOCNO> 12743 </DOCNO>
The large-scale organization of metabolic networks


  In a cell or microorganism the processes that generate mass, energy,
information transfer, and cell fate specification are seamlessly integrated
through a complex network of various cellular constituents and reactions.
However, despite the key role these networks play in sustaining various
cellular functions, their large-scale structure is essentially unknown. Here we
present the first systematic comparative mathematical analysis of the metabolic
networks of 43 organisms representing all three domains of life. We show that,
despite significant variances in their individual constituents and pathways,
these metabolic networks display the same topologic scaling properties
demonstrating striking similarities to the inherent organization of complex
non-biological systems. This suggests that the metabolic organization is not
only identical for all living organisms, but complies with the design
principles of robust and error-tolerant scale-free networks, and may represent
a common blueprint for the large-scale organization of interactions among all
cellular constituents.

</DOC>
<DOC>
<DOCNO> 122036 </DOCNO>
Population synthesis for double white dwarfs I.Close detached systems


  We model the population of double white dwarfs in the Galaxy and find a
better agreement with observations compared to earlier studies, due to two
modifications. The first is the treatment of the first phase of unstable mass
transfer and the second the modelling of the cooling of the white dwarfs. A
satisfactory agreement with observations of the local sample of white dwarfs is
achieved if we assume that the initial binary fraction is ~ 50% and that the
lowest mass white dwarfs (M < 0.3 Msun) cool faster than the most recently
published cooling models predict. With this model we find a Galactic birth rate
of close double white dwarfs of 0.05 yr^{-1}, a birth rate of AM CVn systems of
0.005 yr^{-1}, a merger rate of pairs with a combined mass exceeding the
Chandrasekhar limit (which may be progenitors of SNe Ia) of 0.003 yr^{-1} and a
formation rate of planetary nebulae of 1 yr^{-1}. We estimate the total number
of double white dwarfs in the Galaxy as 2.5 10^8. In an observable sample with
a limiting magnitude V_lim = 15 we predict the presence of ~855 white dwarfs of
which ~220 are close pairs. Of these 10 are double CO white dwarfs of which one
has a combined mass exceeding the Chandrasekhar limit and will merge within a
Hubble time.

</DOC>
<DOC>
<DOCNO> 178657 </DOCNO>
The Single State Dominance Hypothesis and the Two-Neutrino Double Beta


  The hypothesis of the single state dominance (SSD) in the calculation of the
two-neutrino double beta decay of Mo100 is tested by exact consideration of the
energy denominators of the perturbation theory. Both transitions to the ground
state as well as to the 0+ and 2+ excited states of the final nucleus Ru100 are
considered. We demonstrate, that by experimental investigation of the single
electron energy distribution and the angular correlation of the outgoing
electrons, the SSD hypothesis can be confirmed or ruled out by a precise
two-neutrino double beta decay measurement (e.g. by NEMO III collaboration).

</DOC>
<DOC>
<DOCNO> 121325 </DOCNO>
A new scheme of radiation transfer in H II regions including transient


  A new scheme of radiation transfer for understanding infrared spectra of H II
regions, has been developed. This scheme considers non-equilibrium processes
(e. g. transient heating of the very small grains, VSG; and the polycyclic
aromatic hydrocarbon, PAH) also, in addition to the equilibrium thermal
emission from normal dust grains (BG). The spherically symmetric interstellar
dust cloud is segmented into a large number of "onion skin" shells in order to
implement the non-equilibrium processes. The scheme attempts to fit the
observed SED originating from the dust component, by exploring the following
parameters : (i) geometrical details of the dust cloud, (ii) PAH size and
abundance, (iii) composition of normal grains (BG), (iv) radial distribution of
all dust (BG, VSG & PAH).
  The scheme has been applied to a set of five compact H II regions (IRAS
18116- 1646, 18162-2048, 19442+2427, 22308+5812 & 18434-0242) whose spectra are
available with adequate spectral resolution. The best fit models and inferences
about the parameters for these sources are presented.

</DOC>
<DOC>
<DOCNO> 9522 </DOCNO>
Continuity Conditions for the Radial Distribution Function of


  The continuity conditions of the radial distribution function g(r) and its
close relative the cavity function y(r) are studied in the context of the
Percus-Yevick (PY) integral equation for 3D square-well fluids. The cases
corresponding to a well width, (w-1)*d, equal to a fraction of the diameter of
the hard core, d/m, with m=1,2,3 have been considered. In these cases, it is
proved that the function y(r) and its first derivative are everywhere
continuous but eventually the derivative of some order becomes discontinuous at
the points (n+1)d/m, n=0,1,... . The order of continuity (the highest order
derivative of y(r) being continuous at a given point) is found to be
proportional to n in the first case (m=1) and to 2*n in the other two cases
(m=2,3), for large values of n. Moreover, derivatives of y(r) up to third order
are continuous at r=d and r=w*d for w=3/2 and w=4/3 but only the first
derivative is continuous for w=2. This can be understood as a non-linear
resonance effect.

</DOC>
<DOC>
<DOCNO> 178430 </DOCNO>
The Delta I=1/2 rule in non-mesonic weak decay of Lambda-hypernuclei


  By employing recent data on non-mesonic decay of s-shell Lambda-hypernuclei
we study, within the phenomenological model of Block and Dalitz, the validity
of the Delta I=1/2 rule in the Lambda N--> NN process. Due to the low
experimental precision, a possible violation of this rule can be neither proved
nor excluded at present with sufficient accuracy: a pure Delta I=1/2 transition
amplitude is excluded at 40% confidence level.

</DOC>
<DOC>
<DOCNO> 170654 </DOCNO>
Zeno and anti-Zeno effects for photon polarization dephasing


  We discuss a simple, experimentally feasible scheme, which elucidates the
principles of controlling ("engineering") the reservoir spectrum and the
spectral broadening incurred by repeated measurements. This control can yield
either the inhibition (Zeno effect) or the acceleration (anti-Zeno effect) of
the quasi-exponential decay of the observed state by means of frequent
measurements. In the discussed scheme, a photon is bouncing back and forth
between two perfect mirrors, each time passing a polarization rotator. The
horizontal and vertical polarizations can be viewed as analogs of an excited
and a ground state of a two level system (TLS). A polarization beam splitter
and an absorber for the vertically polarized photon are inserted between the
mirrors, and effect measurements of the polarization. The polarization angle
acquired in the electrooptic polarization rotator can fluctuate randomly, e.g.,
via noisy modulation. In the absence of an absorber the polarization
randomization corresponds to TLS decay into an infinite-temperature reservoir.
The non-Markovian nature of the decay stems from the many round-trips required
for the randomization. We consider the influence of the polarization
measurements by the absorber on this non-Markovian decay, and develop a theory
of the Zeno and anti-Zeno effects in this system.

</DOC>
<DOC>
<DOCNO> 85005 </DOCNO>
Field theory model giving rise to "quintessential inflation" without the


  A field theory is developed based on the idea that the effective action of
yet unknown fundamental theory, at energy scale below M_{p} has the form of
expansion in two measures: S=\intd^{4}x[\Phi L_{1}+\sqrt{-g}L_{2}] where the
new measure \Phi is defined using the third-rank antisymmetric tensor. In the
new variables (Einstein frame) all equations of motion take canonical GR form
and therefore models are free of the well-known "defects" that distinguish the
Brans-Dicke type theories from GR. All novelty is revealed only in an unusual
structure of the effective potential U(\phi) and interactions which turns over
intuitive ideas based on our experience in field theory. E.g. the greater
\Lambda we admit in L_{2}, the smaller U(\phi) will be in the Einstein picture.
Field theory models are suggested with explicitly broken global continuos
symmetry which in the Einstein frame has the form \phi\to\phi+const. The
symmetry restoration occurs as \phi\to\infty. A few models are presented where
U is produced with the following shape: for \phi<-M_{p}, U has the form typical
for inflation model, e. g. U=\lambda\phi^4 with \lambda\sim 10^{-14};
for\phi>-M_{p}, U has mainly exponential form U\sim e^{-a\phi/M_{p}} with
variable a: a=14 for -M_{p}<\phi<M_{p} that admits nucleosynthesis; a=2 for
\phi>M_{p} that implies quintessence era. There is no need in any fine tuning
to prevent appearance of the CC term or any other terms that could violate
flatness of U at \phi\ggM_{p}. \lambda\sim 10^{-14} is obtained without fine
tuning as well. Quantized matter fields models, including gauge theories with
SSB can be incorporated without altering mentioned above results. Direct
fermion-inflaton coupling resembles Wetterich's model but it does not lead to
any observable effect at present. SSB does not raise any problem with CC.

</DOC>
<DOC>
<DOCNO> 120424 </DOCNO>
Application of Data Compression Methods to the Redshift-space


  We apply a spherical harmonic analysis to the Point Source Redshift Survey
(PSCz), to compute the real-space galaxy power spectrum and the degree of
redshift distortion caused by peculiar velocities. We employ new parameter
eigenvector and hierarchical data compression techniques, allowing a much
larger number of harmonic modes to be included, and correspondingly smaller
error bars. Using 4644 harmonic modes, compressed to 2278, we find that the
IRAS redshift-space distortion parameter is $\beta = 0.39 \pm 0.12$ and the
amplitude of galaxy clustering on a scale of $k=0.1 \Mpch$ is $\Delta_{\rm
gal}(0.1)=0.42 \pm 0.02$. Combining these we find the amplitude of mass
perturbations is $\Delta_m(0.1)=(0.16\pm0.04) \Omega_m^{-0.6}$. A preliminary
model fitting analysis combining the PSCz amplitudes with the CMB and abundance
of clusters yields the cosmological matter density parameter $\Omega_m=0.16\pm
0.03$, the amplitude of primordial perturbations $Q=(8.4\pm 3.8) \times
10^{-5}$, and the IRAS bias parameter $b=0.84\pm 0.28$.

</DOC>
<DOC>
<DOCNO> 152537 </DOCNO>
The energy-momentum tensor on noncommutative spaces - some pedagogical


  We present the discussion of the energy-momentum tensor of the scalar
$\phi^4$- theory on a noncommutative space. The Noether procedure is performed
at the operator level. Additionally, the broken dilatation symmetry will be
considered in a Moyal-Weyl deformed scalar field theory at the classical level.

</DOC>
<DOC>
<DOCNO> 12611 </DOCNO>
Nucleation of a non-critical phase in a fluid near a critical point


  Phase diagrams of some globular proteins have a fluid-fluid transition as
well as a fluid-crystal transition. Homogeneous nucleation of the crystal from
the fluid phase near the critical point of the fluid-fluid transition is
examined. As the fluid-fluid critical point is approached, the number of
molecules in the critical nucleus, the nucleus at the top of the free energy
barrier to nucleation, is found to diverge as the isothermal compressibility.
This divergence is due to a layer of the fluid phase of width equal to the
fluid's correlation length which surrounds the core of the nucleus; the number
of molecules in a crystalline environment in the nucleus does not diverge. The
free energy barrier to nucleation remains finite but its derivative with
respect to the chemical potential is equal to minus the number of molecules in
the critical nucleus and so diverges.

</DOC>
<DOC>
<DOCNO> 40456 </DOCNO>
Testing neutrino mixing at future collider experiments


  Low energy supersymmetry with bilinear breaking of R-parity leads to a
weak-scale seesaw mechanism for the atmospheric neutrino scale and a radiative
mechanism for the solar neutrino scale. The model has striking implications for
collider searches of supersymmetric particles. Assuming that the lightest SUSY
particle is the lightest neutralino we demonstrate that (i) The neutralino
decays inside the detector even for tiny neutrino masses. (ii) Measurements of
the neutrino mixing angles lead to predictions for the ratios of various
neutralino branching ratios implying an independent test of neutrino physics at
future colliders, such as the Large Hadron Collider or a Linear Collider.

</DOC>
<DOC>
<DOCNO> 101169 </DOCNO>
Heegaard splittings of compact 3-manifolds


  An expository survey article on Heegaard splittings

</DOC>
<DOC>
<DOCNO> 69038 </DOCNO>
A Phenomenological Expression for Deuteron Electromagnetic Form Factors


  For deuteron electromagnetic form factors,perturbative QCD(pQCD) predicts
that $G^{+}_{00}$ becomes the dominate helicity amplitude and that $G^{+}_{+0}$
and $G^{+}_{+-}$ are suppressed by factors $\Lambda_{\rm QCD}/Q$ and
$\Lambda_{\rm QCD}^2/Q^2$ at large $Q^2$,respectively. We try to discuss the
higher order corrections beyond the pQCD asymptotic predictions by
interpolating an analytical form to the intermediate energy region. From
fitting the data,our results show that the helicity-zero to zero matrix element
$G^{+}_{00}$ dominates the gross structure function $A(Q^2)$ in both of the
large and intermediate energy regions; it is a good approximation for
$G^{+}_{+-}$ to ignore the higher order contributions and the higher order
corrections to $G^{+}_{+0}$ should be taken into account due to sizeable
contributions in the intermediate energy region.

</DOC>
<DOC>
<DOCNO> 84168 </DOCNO>
Biconformal Matter Actions


  We extend 2n-dim biconformal gauge theory by including Lorentz-scalar matter
fields of arbitrary conformal weight. We show that for a massless scalar field
of conformal weight zero in a torsion-free biconformal geometry, the solution
is determined by the Einstein equation on an n-dim submanifold, with the
stress-energy tensor of the scalar field as source. The matter field satisfies
the n-dim Klein-Gordon equation.

</DOC>
<DOC>
<DOCNO> 151668 </DOCNO>
Aspects of the D=6, (2,0) Tensor Multiplet


  Some aspects of the $D=6, (2,0)$ tensor multiplet are discussed. Its
formulation as an analytic superfield on a suitably defined superspace and its
superconformal properties are reviewed. Powers of the field strength superfield
define a series of superconformal fields which correspond to the KK multiplets
of D=11 supergravity on an $AdS_7\xz S^4$ background. Correlation functions of
these operators are briefly discussed.

</DOC>
<DOC>
<DOCNO> 99993 </DOCNO>
Fundamental groups of rationally connected varieties


  Let U be an open subset of a unirational variety. We prove that there is
rational curve C in U such that the fundamental group of C surjects onto the
fundamental group of U. As a consequence we obtain new proofs of the theorems
of Harbater and Colliot-Th\'el\`ene on Galois covers and torsors over the
p-adic line. We also obtain examples of pencils of curves of genus <14 whose
monodromy group is the full Teichm\"uller group.

</DOC>
<DOC>
<DOCNO> 84829 </DOCNO>
Grounds for Quantum Geometrodynamics in an extended phase space and its


  Quantum geometrodynamics (QGD) in extended phase space essentially
distinguished from the Wheeler - DeWitt QGD is proposed. The grounds for
constructing a new version of quantum geometrodynamics are briefly discussed.
The main part in the proposed version of QGD is given to the Schrodinger
equation for a wave function of the Universe. The Schrodinger equation carries
information about a chosen gauge condition which fixes a reference system. The
reference system is represented by a continual medium that can be called ``the
gravitational vacuum condencate". A solution to the Schrodinger equation
contains information about the integrated system ``a physical object +
observation means (the gravitational vacuum condensate)". It may be
demonstrated that the gravitational vacuum condensate appears to be a
cosmological evolution factor.

</DOC>
<DOC>
<DOCNO> 14113 </DOCNO>
Microcantilever Studies of Angular Field Dependence of Vortex Dynamics


  Using a nanogram-sized single crystal of BSCCO attached to a microcantilever
we demonstrate in a direct way that in magnetic fields nearly parallel to the
{\it ab} plane the magnetic field penetrates the sample in the form of
Josephson vortices rather than in the form of a tilted vortex lattice. We
further investigate the relation between the Josephson vortices and the pancake
vortices generated by the perpendicular field component.

</DOC>
<DOC>
<DOCNO> 120193 </DOCNO>
Possible Evidence for a Truncated Thin Disk in Seyfert 1 Galaxy NGC4593


  We compile the multi-band spectral energy distribution (SED) of Seyfert 1
galaxy NGC4593, and investigate its optical-to-ultraviolet (OUV) continuum and
iron K\alpha line profile. No strong ``big blue bump'' is found in OUV band.
The iron K\alpha line profile is not as broad as expected from a disk which
extends down to the last stable orbit. Both of them can be modeled by a
truncated thin disk, and support the existence of a truncated thin disk in the
system. It is of much interest that NGC4593 may be a typical object with an
accretion rate \dot{m}=\dot{M}/M_{Edd} \sim 0.01-0.1 and harbors a two
component accretion flow: an outer thin disk and an inner hot flow--possibly
ADAF, analogous to the low and intermediate state of low mass X-ray binaries
(LMXB).

</DOC>
<DOC>
<DOCNO> 101175 </DOCNO>
Discrete Hashimoto surfaces and a doubly discrete smokering flow


  B\"acklund transformations for smooth and ``space discrete''
  Hashimoto surfaces are discussed and a geometric interpretation is given. It
is shown that the complex curvature of a discrete space curve evolves with the
discrete nonlinear Schr\"odinger equation (NLSE) of Ablowitz and Ladik, when
the curve evolves with the Hashimoto or smoke ring flow. A doubly discrete
Hashimoto flow is derived and it is shown, that in this case the complex
curvature of the discrete curve obeys Ablovitz and Ladik's doubly discrete
NLSE. Elastic curves (curves that evolve by rigid motion only under the
Hashimoto flow) in the discrete and doubly discrete case are shown to be the
same. There is an online version of this paper, that can be viewed using any
recent web browser that has JAVA support enabled. It includes two additional
java applets. It can be found at
http://www-sfb288.math.tu-berlin.de/Publications/online/smokeringsOnline/

</DOC>
<DOC>
<DOCNO> 84443 </DOCNO>
The Newtonian Correspondence


  It is shown that the field equations of general relativity in the Einstein
tensor form and the unimodular theory of gravity do not fulfill the
correspondence principle commitment completely. The consistent formalisms are
briefly discussed.

</DOC>
<DOC>
<DOCNO> 68369 </DOCNO>
On the Theory of Fermionic Preheating


  In inflationary cosmology, the particles constituting the Universe are
created after inflation due to their interaction with moving inflaton field(s)
in the process of preheating. In the fermionic sector, the leading channel is
out-of equilibrium particle production in the non-perturbative regime of
parametric excitation, which respects Pauli blocking but differs significantly
from the perturbative expectation. We develop theory of fermionic preheating
coupling to the inflaton, without and with expansion of the universe, for light
and massive fermions, to calculate analytically the occupation number of
created fermions, focusing on their spectra and time evolution. In the case of
large resonant parameter $q$ we extend for rermions the method of successive
parabolic scattering, earlier developed for bosonic preheating. In an expanding
universe parametric excitation of fermions is stochastic. Created fermions very
quickly, within tens of inflaton oscillations, fill up a sphere of radius
$\simeq q^{1/4}$ in monetum space. We extend our formalism to the production of
superheavy fermions and to `instant' fermion creation.

</DOC>
<DOC>
<DOCNO> 39819 </DOCNO>
Measurement of |Vcb| using B0 to D*l nu decays


  The magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vcb has been
measured using B0 to D*l nu decays recorded on the Z0 peak using the OPAL
detector at LEP. The D* to D0 pi+ decays were reconstructed both in the
particular decay modes D0 to K- pi+ and D0 to K- pi+ pi- and via an inclusive
technique. The product of |Vcb| and the decay form factor of the B0 to D* l nu
transition at zero recoil F(1) was measured to be F(1)|Vcb| =
(37.1+-1.0+-2.0)x10^-3, where the uncertainties are statistical and systematic
respectively. By using Heavy Quark Effective Theory calculations for F(1), a
value of |Vcb| = (40.7+-1.1+-2.2+-1.6)x 10^-3 was obtained, where the third
error is due to theoretical uncertainties in the value of F(1). The branching
ratio Br(B0 to D* l nu) was also measured to be (5.26+-0.20+-0.46)%.

</DOC>
<DOC>
<DOCNO> 13327 </DOCNO>
Novel Cholesteric Phase in Dispersions of Nucleic Acids due to Polymeric


  We consider cholesteric liquid-crystalline DNA dispersions, and show that
polymeric (Dau-Cu) complexes, the so-called bridges, between pairs of DNA
molecules may generate a super liquid-crystalline structure (BR-phase). The
latter could have a layered spatial structure and an abnormal optical activity
that could have a bearing upon the intense CD-band observed in DNA-dispersions.

</DOC>
<DOC>
<DOCNO> 100324 </DOCNO>
On the second moment for primes in an arithmetic progression


  Assuming the Generalized Riemann Hypothesis, we obtain a lower bound within a
constant factor of the conjectured asymptotic result for the second moment for
primes in an individual arithmetic progression in short intervals. Previous
results were averaged over all progression of a given modulus. The method uses
a short divisor sum approximation for the von Mangoldt function, together with
some new results for binary correlations of this divisor sum approximation in
arithmetic progressions.

</DOC>
<DOC>
<DOCNO> 116974 </DOCNO>
Control System for the LEDA 6.7-MeV Proton Beam Halo Experiment


  Measurement of high-power proton beam-halo formation is the ongoing
scientific experiment for the Low Energy Demonstration Accelerator (LEDA)
facility. To attain this measurement goal, a 52-magnet beam line containing
several types of beam diagnostic instrumentation is being installed. The
Experimental Physics and Industrial Control System (EPICS) and commercial
software applications are presently being integrated to provide a real-time,
synchronous data acquisition and control system. This system is comprised of
magnet control, vacuum control, motor control, data acquisition, and data
analysis. Unique requirements led to the development and integration of
customized software and hardware. EPICS real-time databases, Interactive Data
Language (IDL) programs, LabVIEW Virtual Instruments (VI), and State Notation
Language (SNL) sequences are hosted on VXI, PC, and UNIX-based platforms which
interact using the EPICS Channel Access (CA) communication protocol.
Acquisition and control hardware technology ranges from DSP-based diagnostic
instrumentation to the PLC-controlled vacuum system. This paper describes the
control system hardware and software design, and implementation.

</DOC>
<DOC>
<DOCNO> 151474 </DOCNO>
Hidden Symmetries of the Open N=2 String


  It is known for ten years that self-dual Yang-Mills theory is the effective
field theory of the open N=2 string in 2+2 dimensional spacetime. We uncover an
infinite set of abelian rigid string symmetries, corresponding to the
symmetries and integrable hierarchy of the self-dual Yang-Mills equations. The
twistor description of the latter naturally connects with the BRST approach to
string quantization, providing an interpretation of the picture phenomenon in
terms of the moduli space of string backgrounds.

</DOC>
<DOC>
<DOCNO> 100934 </DOCNO>
Monodromy groups of regular elliptic surfaces


  Monodromy in analytic families of smooth complex surfaces yields groups of
isotopy classes of orientation preserving diffeomorphisms for each family
member X. For all deformation classes of minimal elliptic surfaces with
p_g>q=0, we determine the monodromy group of a representative X, i.e. the group
of isometries of the intersection lattice L_X:=H_2/torsion generated by the
monodromy action of all families containing X. To this end we construct
families such that any isometry is in the group generated by their monodromies
or does not respect the invariance of the canonical class or the spinor norm.

</DOC>
<DOC>
<DOCNO> 151116 </DOCNO>
Three point functions and the effective lagrangian for the chiral


  We consider the D=4, N=8 supergravity on AdS2 x S2 space. We obtain the
truncated Lagrangian for the bosonic chiral primary fields, and compute the
tree level three-point correlation functions.

</DOC>
<DOC>
<DOCNO> 68258 </DOCNO>
T-odd quark fragmentation function and transverse spin asymmetries in


  We study the time-reversal odd quark fragmentation function and its
consequences on the hard processes. T-odd quark fragmentation function may
arise, although QCD is T-invariant, from the non-perturbative dynamics in the
fragmentation process. Assuming the factorization, we extract the T-odd
fragmentation function from the inclusive pion production in the transversely
polarized proton-proton collision. We then estimate the single spin asymmetry
$A_{OT}$ of the semi-inclusive deep inelastic scattering with unpolarized
lepton and the transversely polarized proton. We also discuss the meson cloud
effects on the transversity distribution $h_1(x)$ of the nucleon. Asymmetry for
the $\pi^-$ production is found to be much smaller than the naive expectation,
since the $d$-quark transversity is considerably suppressed by the pion cloud
effects

</DOC>
<DOC>
<DOCNO> 116373 </DOCNO>
Physical model of leptons : Massive electrons, muons, tauons and their


  The physical model (PhsMdl) of the leptons is offered by means of the PhsMdls
of the vacuum and electron,described in our recent works. It is assumed that
the vacuum is consistent by dynamides, streamlined in junctions of some tight
crystalline lattice. Every dynamide contains a neutral pair of massless
point-like (PntLk) contrary elementary electric charges (ElmElcChrgs):
electrino $(-)$ and positrino $(+)$. The PntLk ElmElcChrgs of the massless
electrino and positrino of some dynamide in the fluctuated vacuum may been
excited or deviated by means of some energy, introduced by some photon or other
micro particles (MicrPrts). The massless leptons (neutrinos) are neutral
long-living solitary spherical vortical oscillation excitations of the
uncharged fluctuating vacuum. The massive leptons are charged long-living
solitary spherical vortical excitations of its fine spread (FnSpr) elementary
electric charge (ElmElcChrg). So-called zitterbewegung is self-consistent
strong-correlated vortical harmonic oscillation motion of the FnSpr ElmElcChrg
of massive leptons. Different leptons have different self-consistent
strong-correlated vortical harmonic oscillation motion of different sizes of
their FnSpr ElmElcChrg, which is determined by their Kompton length $\lambda
=\frac{h}{m C} $, where $m$ is the mass of the massive leptons. At mutual
transition of one massive lepton into another massive lepton its PntLk
ElmElcChrg move up by dint of weak interaction in the form of the charged
intermediate vector meson $W$ from one self-consistent strong-correlated
vortical harmonic oscillation motion of one size into another self-consistent
strong-correlated vortical harmonic oscillation motion of another size.

</DOC>
<DOC>
<DOCNO> 83341 </DOCNO>
Flipturning polygons


  A flipturn is an operation that transforms a nonconvex simple polygon into
another simple polygon, by rotating a concavity 180 degrees around the midpoint
of its bounding convex hull edge. Joss and Shannon proved in 1973 that a
sequence of flipturns eventually transforms any simple polygon into a convex
polygon. This paper describes several new results about such flipturn
sequences. We show that any orthogonal polygon is convexified after at most n-5
arbitrary flipturns, or at most 5(n-4)/6 well-chosen flipturns, improving the
previously best upper bound of (n-1)!/2. We also show that any simple polygon
can be convexified by at most n^2-4n+1 flipturns, generalizing earlier results
of Ahn et al. These bounds depend critically on how degenerate cases are
handled; we carefully explore several possibilities. We describe how to
maintain both a simple polygon and its convex hull in O(log^4 n) time per
flipturn, using a data structure of size O(n). We show that although flipturn
sequences for the same polygon can have very different lengths, the shape and
position of the final convex polygon is the same for all sequences and can be
computed in O(n log n) time. Finally, we demonstrate that finding the longest
convexifying flipturn sequence of a simple polygon is NP-hard.

</DOC>
<DOC>
<DOCNO> 151539 </DOCNO>
The CP(n) Model on Noncommutative Plane


  We construct the consistent CP(n) model on noncommutative plane. The
Bogomolny bound on the energy is saturated by (anti-)self-dual solitons with
integer topological charge, which is independent of their scaling and
orientation. This integer quantization is satisfied for our general solutions,
which turns out regular everywhere. We discuss the possible implication of our
result to the instanton physics in Yang-Mills theories on noncommutative R^4.

</DOC>
<DOC>
<DOCNO> 69317 </DOCNO>
CP Violation - A Brief Review


  Some past, present, and future aspects of CP violation are reviewed. The
discrete symmetries C, P, and T are introduced with an example drawn from
Maxwell's Equations. The history of the discovery of CP violation in the kaon
system is described briefly, and brought up-to-date with a review of recent
results on kaon decays. The candidate theory of CP violation, based on phases
in the Cabibbo-Kobayashi-Maskawa (CKM) matrix, will be tested by studies of $B$
mesons, both in decays to CP eigenstates and in ``direct'' decays; we will soon
learn a great deal more about whether the CKM picture is self-consistent.
Future measurements are noted and some brief remarks are made about the
``other'' manifestation of CP violation, the baryon asymmetry of the Universe.

</DOC>
<DOC>
<DOCNO> 83506 </DOCNO>
Resource-distribution via Boolean constraints


  We consider the problem of searching for proofs in sequential presentations
of logics with multiplicative (or intensional) connectives. Specifically, we
start with the multiplicative fragment of linear logic and extend, on the one
hand, to linear logic with its additives and, on the other, to the additives of
the logic of bunched implications, BI. We give an algebraic method for
calculating the distribution of the side-formulae in multiplicative rules which
allows the occurrence or non-occurrence of a formula on a branch of a proof to
be determined once sufficient information is available. Each formula in the
conclusion of such a rule is assigned a Boolean expression. As a search
proceeds, a set of Boolean constraint equations is generated. We show that a
solution to such a set of equations determines a proof corresponding to the
given search. We explain a range of strategies, from the lazy to the eager, for
solving sets of constraint equations. We indicate how to apply our methods
systematically to large family of relevant systems.

</DOC>
<DOC>
<DOCNO> 170639 </DOCNO>
New optimal tests of quantum nonlocality


  We explore correlation polytopes to derive a set of all Boole-Bell type
conditions of possible classical experience which are both maximal and
complete. These are compared with the respective quantum expressions for the
Greenberger-Horne-Zeilinger (GHZ) case and for two particles with spin state
measurements along three directions.

</DOC>
<DOC>
<DOCNO> 8387 </DOCNO>
Magnetism and superconductivity in underscreened Kondo chains


  We present a one dimensional model of electrons coupled to localized moments
of spin $S\ge 1$ in which magnetism and superconductivity interplay in a
nontrivial manner. This model has a non-Fermi liquid ground state of the chiral
spin liquid type. A non-conventional odd-frequency pairing is shown to be the
dominant instability of the system, together with antiferromagnetism of the
local moments. We argue that this model captures the physics of the
Kondo-Heisenberg spin S=1 chain, in the limit of strong Kondo coupling.
Finally, we discuss briefly the effect of interchain coupling.

</DOC>
<DOC>
<DOCNO> 178866 </DOCNO>
Ground-gamma band mixing and odd-even staggering in heavy deformed


  It is proposed that the odd-even staggering (OES) in the $\gamma$- bands of
heavy deformed nuclei can be reasonably characterized by a discrete
approximation of the fourth derivative of the odd-even energy difference as a
function of angular momentum $L$. This quantity exhibits a well developed
staggering pattern (zigzagging behavior with alternating signs) in rare earth
nuclei and actinides with long $\gamma$- bands ($L\geq 10$). It is shown that
the OES can be interpreted reasonably as the result of the interaction of the
$\gamma$ band with the ground band in the framework of a Vector Boson Model
with SU(3) dynamical symmetry. The model energy expression reproduces
successfully the staggering pattern in all considered nuclei up to $L=12-13$.
The general behavior of the OES effect in rotational regions is studied in
terms of the ground--$\gamma$ band-mixing interaction, showing that strong OES
effect occurs in regions with strong ground--$\gamma$ band-mixing interaction.
The approach used allows a detailed comparison of the OES in $\gamma$ bands
with the other kinds of staggering effects in nuclei and diatomic molecules.

</DOC>
<DOC>
<DOCNO> 84669 </DOCNO>
Removing Line Interference from Gravitational Wave Interferometer Data


  We describe a procedure to identify and remove a class of interference lines
from gravitational wave interferometer data. We illustrate the usefulness of
this technique applying it to prototype interferometer data and removing all
those lines corresponding to the external electricity main supply and related
features.

</DOC>
<DOC>
<DOCNO> 118793 </DOCNO>
Proper motion and membership determination in the young open cluster


  Relative proper motions and cluster membership probabilities of 30 stars
within an area of 14' of diameter centered in the open cluster NGC1662
(\alpha=04^{\rm h}48^{\rm m}, \delta=+10^{\rm o}56') are determined by
combining positions of stars observed by the Valinhos CCD meridian circle with
those from other astrometric catalogues. Our basic source for first epoch of
stars brighter than B=13 magnitudes is the AC2000 Catalogue, which provides a
time baseline of about 90 years, whereas the USNO-A2.0 Catalogue is used for
fainter stars, providing a time baseline of about 40 years in this region.
Average accuracies in proper motion of 2 mas/yr and 7 mas/yr are achieved,
respectively, when the AC2000 or the USNO-A2.0 is used. Membership
determination is obtained by applying the Zhao & He (1990) method. The cluster
proper motion was found to be (-3.2\pm 0.6) mas/yr in right ascension and
(-1.6\pm 0.6) mas/yr in declination.

</DOC>
<DOC>
<DOCNO> 40068 </DOCNO>
Implications of a Low sin(2 beta): A Strategy for Exploring New Flavor


  We explore the would-be consequences of a low value of the CP-violating phase
$\sin2\beta_{\psi K}$. The importance of a reference triangle obtained from
measurements that are independent of $B$--$\bar B$ and $K$--$\bar K$ mixing is
stressed. It can be used to extract separately potential New Physics
contributions to mixing in the $B_d$, $B_s$ and $K$ systems. We discuss several
constructions of this triangle, which will be feasible in the near future. The
discrete ambiguity is at most two-fold and eventually can be completely
removed. Simultaneously, it will be possible to probe for New Physics in
loop-dominated rare decays.

</DOC>
<DOC>
<DOCNO> 120947 </DOCNO>
On the degree of dust extinction in major mergers


  We numerically investigate how fundamental properties of the spectral energy
distribution (SED) of a major gas-rich galaxy merger with dusty starburst are
determined by the initial orbital configuration of the merger. We found that an
infrared luminous galaxy with dusty starburst formed by a nearly
retrograde-retrograde merger suffers the most remarkable dust extinction of
stellar light and consequently shows very red colors. Considering that a
retrograde-retrograde merger does not produce strong and long tidal tails, this
result suggests that a luminous infrared galaxy without clear signs of
interaction and merging shows very large internal dust extinction and redder
colors.These numerical results furthermore imply that the morphology of a
luminous infrared galaxy can correlate with the degree of internal dust
extinction and thus with the shape of the SED, principally because the
morphology of a merger also depends strongly on the initial orbital
configuration of the merger.

</DOC>
<DOC>
<DOCNO> 121338 </DOCNO>
The Normal Cluster Weak Lensing Survey: Mass Profiles and M/L Ratios of


  We present a survey of mass profiles and mass-to-light ratios of eight
typical galaxy clusters at a common redshift (z ~ 0.2). We use weak
gravitational lensing as a probe because it is unique in avoiding any
assumptions about the dynamical state of the clusters. To avoid bias toward the
rare and spectacular clusters that are easy targets for lensing work, we
selected an ensemble of much more common clusters with moderate X-ray
luminosity. Although the survey is still in progress, two conclusions are
emerging: (1) within a cluster, mass follows light very closely on the angular
scales that we can measure, $0.2-2h^{-1}$ Mpc, and (2) there is a significant
cluster-to-cluster scatter in mass-to-light (M/L) ratios despite uniformity of
observing, reduction, and analysis procedures. We also derive an estimate of
$\Omega_{matter}$ based on extrapolation from the mass properties of these
typical clusters. Finally, we discuss the discovery of other clusters in our
fields through their lensing signal.

</DOC>
<DOC>
<DOCNO> 117520 </DOCNO>
A Long Observation of NGC 5548 by BeppoSAX: the High Energy Cut-off,


  NGC 5548 was observed by BeppoSAX in a single long (8 day) observation from
0.2 to 200 keV. We find (1) the spectral variation of the source is produced by
a change of the intrinsic power law slope; (2) a high energy cut-off at $E_c=
115^{+39}_{-27}$ keV with a hint of change of $E_c$ with flux; (3) OVII and
OVIII absorption K edges, and a possible blended OVII-OVIII K$\alpha,\beta$
emission feature at $0.54^{+0.07}_{-0.06}$ keV, inconsistent with a purely
photoionized gas in equilibrium. We propose that the temperature of the
absorbing and emitting gas is $\sim 10^6$ K so that both collisional ionization
and photoionization contribute.

</DOC>
<DOC>
<DOCNO> 84272 </DOCNO>
The gauge factor increase and the hypothetical emerging of the matter


  In the standard model of universe the increase in mass of our observed
expansive and isotropic relativistic Universe is explained by the hypothetical
assumption of matter objects emerging on the horizon (of the most remote
visibility). However, the mathematical-physical analysis of the increase of
Universe gauge factor shows that this hypothetical assumption is non-compatible
with the variants of the standard model of universe by which - according to the
standard model of universe - can be described the expansive evolution of the
Universe.

</DOC>
<DOC>
<DOCNO> 10135 </DOCNO>
Friction, order, and transverse pinning of a two-dimensional elastic


  Frictional phenomena of two-dimensional elastic lattices are studied
numerically based on a two-dimensional Frenkel-Kontorova model with impurities.
It is shown that impurities can assist the depinning. We also investigate
anisotropic ordering and transverse pinning effects of sliding lattices, which
are characteristic of the moving Bragg glass state and/or transverse glass
state. Peculiar velocity dependence of the transverse pinning is observed in
the presence of both periodic and random potentials and discussed in the
relation with growing order and discommensurate structures.

</DOC>
<DOC>
<DOCNO> 178669 </DOCNO>
Relativistic Contributions to Deuteron Photodisintegration in the


  In plane wave one-body approximation the reaction of deuteron
photodisintegration is considered in the framework of the Bethe-Salpeter
formalism for two-nucleon system. Results are obtained for deuteron vertex
function, which is the solution of the homogeneous Bethe-Salpeter equation with
a multi-rank separable interaction kernel, with a given analytical form. A
comparison is presented with predictions of non-relativistic, quasipotential
approaches and the equal time approximation. It is shown that important
contributions come from the boost in the arguments of the initial state vertex
function and the boost on the relative energy in the one-particle propagator
due to recoil.

</DOC>
<DOC>
<DOCNO> 68374 </DOCNO>
Decay widths of the neutral CP-even MSSM Higgs bosons in the


  In the Minimal Supersymmetric Standard Model (MSSM) we incorporate the
Higgs-boson propagator corrections, evaluated up to two-loop order, into the
prediction of $\Gamma$(h -> ff) and BR(h -> ff) for f = b, c, $\tau$. The
propagator corrections consist of the full one-loop contribution, including the
effects of non-vanishing external momentum, and corrections of O(alpha alpha_s)
at the two-loop level. The results are supplemented with the dominant one-loop
QED corrections and final state QCD corrections from both gluons and gluinos.
The effects of the two-loop propagator corrections and of the one-loop gluino
contributions are investigated in detail. Our results are compared with the
result obtained within the renormalization group approach. Agreement within 10%
is found for most parts of the MSSM parameter space.

</DOC>
<DOC>
<DOCNO> 169671 </DOCNO>
Reply to "Comment on 'Quantum Phase Shift Caused by Spatial


  We describe a force-free phase shift due only to temporal geometric boundary
conditions placed on a neutron deBroglie wave packet.

</DOC>
<DOC>
<DOCNO> 12084 </DOCNO>
Strongly Non-Equilibrium Bose-Einstein Condensation in a Trapped Gas


  We present a qualitative (and quantitative, at the level of estimates)
analysis of the ordering kinetics in a strongly non-equilibrium state of a
weakly interacting Bose gas, trapped with an external potential. At certain
conditions, the ordering process is predicted to be even more rich than in the
homogeneous case. Like in the homogeneous case, the most characteristic feature
of the full-scale non-equilibrium process is the formation of superfluid
turbulence.

</DOC>
<DOC>
<DOCNO> 8943 </DOCNO>
Non-supersymmetric cousins of supersymmetric gauge theories: quantum


  I point out that standard two dimensional, asymptotically free, non-linear
sigma models, supplemented with terms giving a mass to the would-be Goldstone
bosons, share many properties with four dimensional supersymmetric gauge
theories, and are tractable even in the non-supersymmetric cases. The space of
mass parameters gets quantum corrections analogous to what was found on the
moduli space of the supersymmetric gauge theories. I focus on a simple purely
bosonic example exhibiting many interesting phenomena: massless solitons and
bound states, Argyres-Douglas-like CFTs and duality in the infrared, and
rearrangement of the spectrum of stable states from weak to strong coupling. At
the singularities on the space of parameters, the model can be described by a
continuous theory of randomly branched polymers, which is defined beyond
perturbation theory by taking an appropriate double scaling limit.

</DOC>
<DOC>
<DOCNO> 102567 </DOCNO>
The 42 Assessors and the Box-Kites they fly: Diagonal Axis-Pair Systems


  G. Moreno's abstract depiction of the Sedenions' normed zero-divisors, as
homomorphic to the exceptional Lie group G2, is fleshed out by exploring
further structures the A-D-E approach of Lie algebraic taxonomy keeps hidden. A
breakdown of table equivalence among the half a trillion multiplication schemes
the Sedenions allow is found; the 168 elements of PSL(2,7), defining the finite
projective triangle on which the Octonions' 480 equivalent multiplication
tables are frequently deployed, are shown to give the exact count of primitive
unit zero-divisors in the Sedenions. (Composite zero-divisors, comprising all
points of certain hyperplanes of up to 4 dimensions, are also determined.) The
168 are arranged in point-set quartets along the 42 Assessors (pairs of
diagonals in planes spanned by pure imaginaries, each of which zero-divides
only one such diagonal of any partner Assessor). These quartets are
multiplicatively organized in systems of mutually zero-dividing trios of
Assessors, a D4-suggestive 28 in number, obeying the 6-cycle crossover logic of
trefoils or triple zigzags. 3 trefoils and 1 zigzag determine an octahedral
vertex structure we call a box-kite -- seven of which serve to partition
Sedenion space. By sequential execution of proof-driven production rules, a
complete interconnected box-kite system, or Seinfeld production (German for
field of being; American for 1990's television's Show About Nothing), can be
unfolded from an arbitrary Octonion and any (save for two) of the Sedenions.
Indications for extending the results to higher dimensions and different
dynamic contexts are given in the final pages.

</DOC>
<DOC>
<DOCNO> 118012 </DOCNO>
Spark Model for Pulsar Radiation Modulation Patterns


  A non-stationary polar gap model first proposed by Ruderman & Sutherland
(1975) is modified and applied to spark-associated pulsar emission at radio
wave-lengths. It is argued that under physical and geometrical conditions
prevailing above pulsar polar cap, highly non-stationary spark discharges do
not occur at random positions. Instead, sparks should tend to operate in well
determined preferred regions. At any instant the polar cap is populated as
densely as possible with a number of two-dimensional sparks with a
characteristic dimension as well as a typical distance between adjacent sparks
being about the polar gap height. Our model differs, however, markedly from its
original 'hollow cone' version. The key feature is the quasi-central spark
driven by pair production process and anchored to the local pole of a
sunspot-like surface magnetic field. This fixed spark prevents the motion of
other sparks towards the pole, restricting it to slow circumferential drift
across the planes of field lines converging at the local pole. We argue that
the polar spark constitutes the core pulsar emission, and that the annular
rings of drifting sparks contribute to conal components of the pulsar beam. We
found that the number of nested cones in the beam of typical pulsar should not
excced three; a number also found by Mitra & Deshpande (1999) using a
completely different analysis.

</DOC>
<DOC>
<DOCNO> 8733 </DOCNO>
Nature of Ground State Incongruence in Two-Dimensional Spin Glasses


  We rigorously rule out the appearance of multiple domain walls between ground
states in 2D Edwards-Anderson Ising spin glasses (with periodic boundary
conditions and, e.g., Gaussian couplings). This supports the conjecture that
there is only a single pair of ground states in these models.

</DOC>
<DOC>
<DOCNO> 71128 </DOCNO>
Branching ratios for B_{d,s}->J/psi eta and B_{d,s}->eta l+l-,


  Estimates of the branching ratios for B_{d,s}->J/psi eta and B_{d,s}->eta
l+l- are obtained by SU(3) relation to B_d->J/psi K and B_d->K l+l-,
respectively, as functions of the eta mixing parameter, theta_P. Based on these
estimates, a discussion of the prospects for HERA-B, CDF-II, and ATLAS on these
processes is given. The CP violation in B_{d,s}-> J/psi eta is analyzed in
depth and a method to extract the angle gamma of the unitarity triangle is
discussed. Finally, a possible method to constrain the Wilson coefficient
C_{10A} from measurements on semileptonic B decays such as B_d->J/psi K and
B_s->eta l+l- is proposed along with a discussion of the prospects for future
experiments and form factor calculations to reach the precision required for
this method to be interesting.

</DOC>
<DOC>
<DOCNO> 102517 </DOCNO>
Notions of double for Lie algebroids


  We define an abstract notion of double Lie algebroid, which includes as
particular cases: (1) the double Lie algebroid of a double Lie groupoid in the
sense of the author, such as the iterated tangent bundle of an ordinary
manifold, and various iterated tangent/cotangent constructions in symplectic
and Poisson geometry; (2) the double of a Lie bialgebra; (3) the double of a
matched pair, or twilled extension, of Lie algebras, and a corresponding
construction for matched pairs of general Lie algebroids in the sense of Mokri
and of J.-H. Lu.
  We prove that, given any abstract Lie bialgebroid, the `double cotangent' has
a structure of double Lie algebroid, which reduces to the classical Drinfel'd
double in the Lie bialgebra case.
  The key to the compatibility conditions between the structures in an abstract
double Lie algebroid is an associated Lie bialgebroid in the sense of the
author and Ping Xu.

</DOC>
<DOC>
<DOCNO> 117107 </DOCNO>
Numerical Calculation of Coherent Synchrotron Radiation Effects Using


  Coherent synchrotron radiation (CSR) occurs when short bunches travel on
strongly bent trajectories. Its effects on high-quality beams can be severe and
are well understood qualitatively. For quantitative results, however, one has
to rely on numerical methods. There exist several simulation codes utilizing
different approaches. We describe in some detail the code TraFiC4 developed at
DESY for design and analysis purposes, which approaches the problem from first
principles and solves the equations of motion either perturbatively or
self-consistently. We present some calculational results and comparison with
experimental data. Also, we give examples of how the code can be used to design
beamlines with minimal emittance growth due to CSR.

</DOC>
<DOC>
<DOCNO> 69562 </DOCNO>
Report of the Beyond the MSSM Subgroup for the Tevatron Run II


  There are many low-energy models of supersymmetry breaking parameters which
are motivated by theoretical and experimental considerations. Here, we discuss
some of the lesser-known theories of low-energy supersymmetry, and outline
their phenomenological consequences. In some cases, these theories have more
gauge symmetry or particle content than the Minimal Supersymmetric Standard
Model. In other cases, the parameters of the Lagrangian are unusual compared to
commonly accepted norms (e.g., Wino LSP, heavy gluino LSP, light gluino, etc.).
The phenomenology of supersymmetry varies greatly between the different models.
Correspondingly, particular aspects of the detectors assume greater or lesser
importance. Detection of supersymmetry and the determination of all parameters
may well depend upon having the widest possible view of supersymmetry
phenomenology.

</DOC>
<DOC>
<DOCNO> 9823 </DOCNO>
Energy levels and far-infrared spectroscopy for two electrons in a


  The effects of electron-electron interaction of a two-electron nanoring on
the energy levels and far-infrared (FIR) spectroscopy have been investigated
based on a model calculation which is performed within the exactly numerical
diagonalization. It is found that the interaction changes the energy spectra
dramatically, and also shows significant influence on the FIR spectroscopy. The
crossings between the lowest spin-singlet and triplet states induced by the
coulomb interaction are clearly revealed. Our results are related to the
experiment recently carried out by A. Lorke et al. [Phys. Rev. Lett. 84, 2223
(2000)].

</DOC>
<DOC>
<DOCNO> 69249 </DOCNO>
Neutrino self-energy in a magnetized medium in arbitrary $\xi$-gauge


  We calculate the one-loop neutrino self-energy in a magnetized plasma to all
orders in the magnetic field. The calculation is done in a general gauge. We
obtain the dispersion relation and effective potential for neutrinos in a
CP-symmetric plasma under various conditions, and show that, while the
self-energy depends on the gauge parameter $\xi$, the dispersion relation and
effective potential to leading order are independent of it.

</DOC>
<DOC>
<DOCNO> 69553 </DOCNO>
Overlapping Instantons


  Overlapping instantons have an action density profile that significantly
deviates from the simple addition of the density profiles of single instantons.
This turns out to have important consequences for identifying the proper
instanton content of a given configuration. Most dramatic is the case where the
instantons are parallel in group space, leading to the effect of hiding large
instantons. Sufficiently large instantons can have important contributions to a
confining interaction.

</DOC>
<DOC>
<DOCNO> 117155 </DOCNO>
The No-sticking Effect in Ultra-cold Collisions


  We provide the theoretical basis for understanding the phenomenon in which an
ultra cold atom incident on a possibly warm target will not stick, even in the
large $n$ limit where $n$ is the number of internal degrees of freedom of the
target. Our treatment is non-perturbative in which the full many-body problem
is viewed as a scattering event purely within the context of scattering theory.
The question of sticking is then simply and naturally identified with the
formation of a long lived resonance. One crucial physical insight that emerges
is that the many internal degrees of freedom serve to decohere the incident one
body wavefunction, thus upsetting the delicate interference process necessary
to form a resonance in the first place. This is the physical reason for not
sticking.

</DOC>
<DOC>
<DOCNO> 99877 </DOCNO>
Quantum co-adjoint orbits of $\MD_4$-groups


  Using $\star$-product on Co-adjoint orbits (K-orbits) of the $\MD_4$- groups
we obtain quantum half-planes, quantum hyperbolic cylinders, quantum hyperbolic
paraboloids...via Fedosov deformation quantization. From this we have
corresponding unitary representations of the $\MD_4$- groups. Particularly, for
groups $\G_{4,2,3(\phi)}; \G_{4,2,4}; \G_{4,3,4(\phi)}$ and $ \G_{4,4,1} $,
which are neither nilpotent nor exponential, we obtain the explicit formulas.

</DOC>
<DOC>
<DOCNO> 102323 </DOCNO>
A Diagonal on the Associahedra


  An associahedral set is a combinatorial object generated by Stasheff
associahedra K_n and equipped with appropriate face and degeneracy operators.
Associahedral sets are similar in many ways to simplicial or cubical sets. In
this paper we give a formal definition of an associahedral set, discuss some
naturally occurring examples and construct an explicit geometric diagonal
\Delta :C_*(K_n) --> C_*(K_n) \otimes C_*(K_n) on the cellular chains C_*(K_n).
The diagonal \Delta, which is analogous to the Alexander-Whitney diagonal on
the simplices, gives rise to a diagonal on any associahedral set and leads
immediately to an explicit diagonal on the A_\infty operad. As an application
of this, we use the diagonal \Delta to define a tensor product in the A_\infty
category.

</DOC>
<DOC>
<DOCNO> 100553 </DOCNO>
Indecomposable Higher Chow cycles on Jacobians


  We construct some natural cycles with trivial regulator in the higher Chow
groups of Jacobians. For hyperelliptic curves we use a criterion due to J.
Lewis to prove that the cycles we construct are indecomposable, and then use a
specialization argument to prove indecomposability for more general curves.
  Please note that math.AG/9909062 has become an obsolete version of some of
the results in the present paper.

</DOC>
<DOC>
<DOCNO> 80590 </DOCNO>
Optimizing Chirality and Scaling of Lattice Fermions


  If we construct a lattice fermion formulation, there are a number of goals to
be considered: doubling should be avoided; even at finite lattice spacing, we
want to represent chiral symmetry in a sound way; and we are seeking a good
scaling behavior. Conceptually we have to require locality, and for practical
purposes we even desire a high level of locality. A further issue is a good
approximation to rotation invariance. Last but not least the formulation should
be simple enough to allow for efficient simulations. Here we report on a
construction, which is designed to do justice to all of these goals.

</DOC>
<DOC>
<DOCNO> 118910 </DOCNO>
Excitation of Oscillations in the Magnetic Network on the Sun


  We examine the excitation of oscillations in the magnetic network of the Sun
through the footpoint motion of photospheric magnetic flux tubes located in
intergranular lanes. The motion is derived from a time series of
high-resolution G band and continuum filtergrams using an object-tracking
technique. We model the response of the flux tube to the footpoint motion in
terms of the Klein-Gordon equation, which is solved analytically as an initial
value problem for transverse (kink) waves. We compute the wave energy flux in
upward propagating transverse waves. In general we find that the injection of
energy into the chromosphere occurs in short-duration pulses, which would lead
to a time variability in chromospheric emission that is incompatible with
observations. Therefore, we consider the effects of turbulent convective flows
on flux tubes in intergranular lanes. The turbulent flows are simulated by
adding high-frequency motions (periods 5-50 s) with an amplitude of 1 km
s^{-1}. The latter are simulated by adding random velocity fluctuations to the
observationally determined velocities. In this case we find that the energy
flux is much less intermittent and can in principle carry adequate energy for
chromospheric heating.

</DOC>
<DOC>
<DOCNO> 120477 </DOCNO>
Correlations in the Lyman alpha forest: testing the gravitational


  We investigate correlations between the long wavelength fluctuations and the
small scale power in the Lyman alpha forest. We show that such correlations can
be used to discriminate between fluctuations induced by large scale structure
and those produced by non-gravitational processes such as fluctuations in the
continuum of the quasar or in the temperature of the gas. The correlations
observed in Q1422+231 are in agreement with the predictions of numerical
simulations, indicating that non-gravitational fluctuations on large scales
have to be small compared those induced by the large scale structure of the
universe, contributing less than 10 % (95 % confidence) of the observed power.
We also show the sensitivity of such statistics to the equation of state of the
gas and its mean temperature.

</DOC>
<DOC>
<DOCNO> 150491 </DOCNO>
D-instanton induced interactions on a D3-brane


  Non-perturbative features of the derivative expansion of the effective action
of a single D3-brane are obtained by considering scattering amplitudes of open
and closed strings. This motivates expressions for the coupling constant
dependence of world-volume interactions of the form $(\partial F)^4$ (where F
is the Born-Infeld field strength), $(\partial^2\phi)^4$ (where $\phi$ are the
normal coordinates of the D3-brane) and other interactions related by $\calN=4$
supersymmetry. These include terms that transform with non-trivial modular
weight under Montonen-Olive duality. The leading D-instanton contributions that
enter into these effective interactions are also shown to follow from an
explicit stringy construction of the moduli space action for the
D-instanton/D3-brane system in the presence of D3-brane open-string sources
(but in the absence of a background antisymmetric tensor potential). Extending
this action to include closed-string sources leads to a unified description of
non-perturbative terms in the effective action of the form (embedding
curvature)$^2$ together with open-string interactions that describe
contributions of the second fundamental form.

</DOC>
<DOC>
<DOCNO> 10902 </DOCNO>
Universal correlations of one-dimensional electrons at low density


  We summarize results on the asymptotics of the two-particle Green functions
of interacting electrons in one dimension. Below a critical value of the
chemical potential the Fermi surface vanishes, and the system can no longer be
described as a Luttinger liquid. Instead, the non-relativistic Fermi gas with
infinite point-like repulsion becomes the universal model for the
long-wavelength, low temperature physics of the one-dimensional electrons. This
model, which we call the impenetrable electron gas, allows for a rigorous
mathematical treatment. In particular, a so-called determinant representation
for the two particle Green function could be derived. This determinant
representation is related to an integrable classical evolution equation and to
a Riemann-Hilbert problem, that enable the exact calculation of the asymptotics
of the two-particle Green functions.

</DOC>
<DOC>
<DOCNO> 40028 </DOCNO>
Measurement of the Relative Branching Fraction of $\Upsilon(4S)$ to


  We analyze 9.7 x 10^6 B\bar{B}$ pairs recorded with the CLEO detector to
determine the production ratio of charged to neutral B-meson pairs produced at
the Y(4S) resonance. We measure the rates for B^0 -> J/psi K^{(*)0} and B^+ ->
J/psi K^{(*)+} decays and use the world-average B-meson lifetime ratio to
extract the relative widths f+-/f00 = Gamma(Y(4S) -> B+B-)/Gamma(Y(4S) ->
B0\bar{B0}) = = 1.04 +/- 0.07(stat) +/- 0.04(syst). With the assumption that
f+- + f00 = 1, we obtain f00 = 0.49 +/- 0.02(stat) +/- 0.01(syst) and f+- =
0.51 +/- 0.02(stat) +/- 0.01(syst). This production ratio and its uncertainty
apply to all exclusive B-meson branching fractions measured at the Y(4S)
resonance.

</DOC>
<DOC>
<DOCNO> 11171 </DOCNO>
Optical phonons in a quarter-filled 1D Hubbard model


  The influence of dispersion-less quantum optical phonons on the phase diagram
of a quarter-filled Hubbard chain is studied using the Density-matrix
renormalization group technique. The ground state phase diagram is obtained for
frequencies corresponding to the intra-molecular vibrations in organic
conductors. For high vibrational modes the system is only slightly affected by
the electron-phonons coupling. It remains in a L\"uttinger liquid phase as long
as the electronic repulsion is larger than the polaronic binding energy. For
low vibrational modes the phase diagram is very rich. A noticeable point is the
existence of a $4k_F$ CDW phase for small values of the correlation strength.
For realistic values of the electron repulsion and of the electron-phonons
coupling constant a large phonons-mediated reduction of the L\"uttinger liquid
parameter $K_\rho$ was found compared to the pure electronic model.

</DOC>
<DOC>
<DOCNO> 13375 </DOCNO>
A model of interband radiative transitions


  We consider a simple model which is a caricature of a crystal interacting
with a radiation field. The model has two bands of continuous spectrum and the
particle can pass from the upper one to the lower by radiating a photon, the
coupling between the excited and deexcited states being of a Friedrichs type.
Under suitable regularity and analyticity assumptions we find the continued
resolvent and show that for weak enough coupling it has a curve-type
singularity in the lower halfplane which is a deformation of the upper-band
spectral cut. We then find a formula for the decay amplitude and show that for
a fixed energy it is approximately exponential at intermediate times, while the
tail has a power-like behaviour.

</DOC>
<DOC>
<DOCNO> 9576 </DOCNO>
The effect of rare regions on a disordered itinerant quantum


  We study the quantum phase transition of an itinerant antiferromagnet with
cubic anisotropy in the presence of quenched disorder, paying particular
attention to the locally ordered spatial regions that form in the Griffiths
region. We derive an effective action where these rare regions are described in
terms of static annealed disorder. A one loop renormalization group analysis of
the effective action shows that for order parameter dimensions $p<4$ the rare
regions destroy the conventional critical behavior. For order parameter
dimensions $p>4$ the critical behavior is not influenced by the rare regions,
it is described by the conventional dirty cubic fixed point. We also discuss
the influence of the rare regions on the fluctuation-driven first-order
transition in this system.

</DOC>
<DOC>
<DOCNO> 117827 </DOCNO>
WSRT 1.4 GHz Observations of the Hubble Deep Field


  We present WSRT 1.38 GHz observations of the Hubble Deep Field (and flanking
fields). 72 hours of data were combined to produce the WSRT's deepest image
yet, achieving an r.m.s. noise level of 8 microJy per beam. We detect radio
emission from galaxies both in the HDF and HFF which have not been previously
detected by recent MERLIN or VLA studies of the field.

</DOC>
<DOC>
<DOCNO> 101577 </DOCNO>
How to make a triangulation of S^3 polytopal


  We introduce a method of studying triangulations of S^3 that connects
topological and geometrical approaches. We consider local moves called
expansions, that generalize stellar subdivisions of simplicial complexes. Let
d(T) be the length of a shortest sequence of expansions relating a
triangulation T of S^3 with the boundary complex of a convex 4-polytope. In
this paper we obtain an upper bound for d(T) in terms of the number n of
tetrahedra of T. The bound is exponential in n^2, and we prove that in general
one can not replace it by a subexponential bound.
  As a tool, we introduce a new numerical invariant p(T), called polytopality.
Although its definition is purely topological, p(T) is sensitive for geometric
properties of T, as we obtain both lower and upper bounds for d(T) in terms of
p(T). Our results are partially based on a complexity analysis of the
Rubinstein-Thompson algorithm (see math.GT/0007032), and yield a new and
conceptionally very simple recognition algorithm for S^3.

</DOC>
<DOC>
<DOCNO> 84130 </DOCNO>
Quantum Isotropization of the Universe


  We consider minisuperspace models constituted of Bianchi I geometries with a
free massless scalar field. The classical solutions are always singular (with
the trivial exception of flat space-time), and always anisotropic once they
begin anisotropic. When quantizing the system, we obtain the Wheeler-DeWitt
equation as a four-dimensional massless Klein-Gordon equation. We show that
there are plenty of quantum states whose corresponding bohmian trajectories may
be non-singular and/or presenting large isotropic phases, even if they begin
anisotropic, due to quantum gravitational effects. As a specific example, we
exhibit field plots of bohmian trajectories for the case of gaussian
superpositions of plane wave solutions of the Wheeler-DeWitt equation which
have those properties. These conclusions are valid even in the absence of the
scalar field.

</DOC>
<DOC>
<DOCNO> 152178 </DOCNO>
Phenomenological Consequences of Non-commutative QED


  In the context of the noncommutative QED we consider few phenomena which
reflect the noncommutativity. In all of them the new interactions in the
Feynmann diagrams that are responsible for the deviation from the standard QED
results. These deviations appear as the violations of Lorentz symmetry. We
suggest experimental situations where these effects may be observed. The extra
phases have far reaching consequences including violation of crossing symmetry.
Considering the e-p scattering and Compton scattering the electric dipole
moments of the electron and the photon is calculated.

</DOC>
<DOC>
<DOCNO> 178641 </DOCNO>
Effect of differences in proton and neutron density distributions on


  The neutron and proton density distributions obtained in constrained
Hartree-Fock-Bogolyubov calculations with the Gogny force along the fission
paths of 232Th, 236U, 238U and 240Pu are analyzed.
  Significant differences in the multipole deformations of neutron and proton
densities are found. The effect on potential energy surfaces and on barrier
heights of an additional constraint imposing similar spatial distributions to
neutrons and protons, as assumed in macroscopic-microscopic models, is studied.

</DOC>
<DOC>
<DOCNO> 69789 </DOCNO>
Halo Properties in Cosmological Simulations of Self-Interacting Cold


  We present a comparison of halo properties in cosmological simulations of
collisionless cold dark matter (CDM) and self-interacting dark matter (SIDM)
for a range of dark matter cross sections. We find, in agreement with various
authors, that CDM yields cuspy halos that are too centrally concentrated as
compared to observations. Conversely, SIDM simulations using a Monte Carlo
N-body technique produce halos with significantly reduced central densities and
flatter cores with increasing cross section. We introduce a concentration
parameter based on enclosed mass that we expect will be straightforward to
determine observationally, unlike that of Navarro, Frenk & White, and provide
predictions for SIDM and CDM. SIDM also produces more spherical halos than CDM,
providing possibly the strongest observational test of SIDM. We discuss our
findings in relation to various relevant observations as well as SIDM
simulations of other groups. Taking proper account of simulation limitations,
we find that a dark matter cross section per unit mass of sigma_DM ~=
10^{-23}-10^{-24} cm^2/GeV is consistent with all current observational
constraints.

</DOC>
<DOC>
<DOCNO> 151388 </DOCNO>
On the cohomological derivation of topological Yang-Mills theory


  Topological Yang-Mills theory is derived in the framework of Lagrangian BRST
cohomology.

</DOC>
<DOC>
<DOCNO> 151728 </DOCNO>
Generalized Fractional Supersymmetry associated to different species of


  We consider multiple species of anyons characterized by different statistical
parameters. First, we redefine the anyonic algebra and then generalize this
definition by constructing the anyonic superalgebra. Finally, we use these
tools to generalize the fractional supersymmetry already discussed in the paper
[J. Douari and Y. Hassouni, Fractional supersymmetry through generalized
anyonic algebra, hep-th/0007165, Preprint ICTP].

</DOC>
<DOC>
<DOCNO> 85332 </DOCNO>
Quantum nondemolition measurements in a Paul trap


  In this work a family of quantum nondemolition variables for the case of a
particle caught in a Paul trap is obtained. Afterwards, in the context of the
so called restricted path integral formalism, a continuous measuring process
for this family of parameters is considered, and then the corresponding
propagators are calculated. In other words, the time evolution of a particle in
a Paul trap, when the corresponding quantum nondemolition parameter is being
continuously monitored, is deduced. The probabilities associated with the
possible measurement outputs are also obtained, and in this way new theoretical
results emerge, which could allow us to confront the predictions of this
restricted path integral formalism with the readouts of some future
experiments.

</DOC>
<DOC>
<DOCNO> 8266 </DOCNO>
Response-theory for nonresonant hole burning: Stochastic dynamics


  Using non-linear response theory the time signals relevant for nonresonant
spectral hole burning are calculated. The step-reponse function following the
application of a high amplitude ac field (pump) and an intermediate waiting
period is shown to be the sum of the equilibrium integrated response and a
modification due to the preparation via ac irradiation. Both components are
calculated for a class of stochastic dipole reorientation models. The results
indicate that the method can be used for a clearcut distinction of
homogeneously and heterogeneously broadened susceptibilities as they occur in
the relaxation of supercooled liquids or other disordered materials. This is
because only in the heterogeneous case is a frequency selective modification of
the response possible.

</DOC>
<DOC>
<DOCNO> 71434 </DOCNO>
Dynamical (Super)Symmetry Breaking


  Dynamical Symmetry Breaking (DSB) is a concept theorists rely on very often
in the discussions of strong dynamics, model building, and hierarchy problems.
In this talk, I will discuss why this is such a permeating concept among
theorists and how they are used in understanding physics. I also briefly review
recent progress in using dynamical symmetry breaking to construct models of
supersymmetry breaking and fermion masses.

</DOC>
<DOC>
<DOCNO> 178667 </DOCNO>
The Reaction $pp\to pp\eta$ and the eta-Nucleon and Nucleon-Nucleon


  The $\pi$, $\eta$ and $\rho$ exchange contributions to the cross-section for
the reaction $pp\to pp\eta$ near threshold are calculated with a
phenomenological description of the intermediate S11 (N(1535)) resonance for
all exchange mechanisms. The final state interaction in the $pp$ system is
described by realistic nucleon-nucleon interaction models. The sensitivity of
the results to the phenomenological models for the $\eta$-nucleon transition
amplitude and the nucleon-nucleon interaction is explored. The $\eta$ exchange
mechanism is found to play a dominant role. The off-shell behavior of the $\eta
N \to \eta N$ amplitude within the $\eta-$exchange amplitude leads to a result
significantly different from that obtained with the constant scattering length
approximation. The two-nucleon amplitudes that are associated with the short
range components of the nucleon-nucleon interaction contribute significantly to
the cross section.

</DOC>
<DOC>
<DOCNO> 11942 </DOCNO>
World-Wide Web scaling exponent from Simon's 1955 model


  Recently, statistical properties of the World-Wide Web have attracted
considerable attention when self-similar regimes have been observed in the
scaling of its link structure. Here we recall a classical model for general
scaling phenomena and argue that it offers an explanation for the World-Wide
Web's scaling exponent when combined with a recent measurement of internet
growth.

</DOC>
<DOC>
<DOCNO> 10085 </DOCNO>
Simple Fluids with Complex Phase Behavior


  We find that a system of particles interacting through a simple isotropic
potential with a softened core is able to exhibit a rich phase behavior
including: a liquid-liquid phase transition in the supercooled phase, as has
been suggested for water; a gas-liquid-liquid triple point; a freezing line
with anomalous reentrant behavior. The essential ingredient leading to these
features resides in that the potential investigated gives origin to two
effective core radii.

</DOC>
<DOC>
<DOCNO> 120963 </DOCNO>
Can luminosity distance measurements probe the equation of state of dark


  Distance measurements to Type Ia supernovae (SNe Ia) at cosmological
distances indicate that the Universe is accelerating and that a large fraction
of the critical energy density exists in a component with negative pressure.
Various hypotheses on the nature of this ``dark energy'' can be tested via
their prediction for the equation of state of this component. If the dark
energy is due to a scalar field, its equation of state will in general vary
with time and is related to the potential of the field. We review the intrinsic
degeneracies of luminosity distance measurements and compute the expected
accuracies that can be obtained for the equation of state parameter from a
realistic high statistic SNe Ia experiment.

</DOC>
<DOC>
<DOCNO> 122650 </DOCNO>
From the Top to the Bottom of the Main Sequence: A Complete Mass


  We present very deep and accurate photometry of the open cluster M35 (VRIc
filters). We have covered a region of 27.5x27.5 square arcmin.
  The data range from Ic=12.5 to 23.5 mag, and the color intervals are
0.4\le(V-I)c\le3.0, 0.5\le(R-I)c\le2.5. Roughly, these values span from 1.6
M_\odot down to the substellar limit. By using the location of the stars on
color-magnitude and color-color diagrams, we have selected candidate members of
this cluster. We have merged our sample with previously published data and
obtained a color-magnitude diagram for the complete stellar population of the
cluster, covering the spectral range early B - mid M. The Mass Function
increases monotonically, when plotted in a log-log form, until it reaches ~0.8
M_\odot (\alpha=2.59). It remains shallower for less massive stars (\alpha=0.81
for 0.8-0.2 M_\odot), whereas a decrease ins observed for stars close to the
substellar regime. The total mass of the cluster is ~1600 M_\odot in the area
covered by this study.

</DOC>
<DOC>
<DOCNO> 12282 </DOCNO>
A ^4He shadow wavefunction with an inverse seventh power


  Many ground state studies of $^4$He using a shadow wave function with an
inverse fifth power McMillan particle-particle correlation function have
yielded radial distribution functions with misplaced peaks. It has been
conjectured that this is due to the specific choice of the McMillan correlation
function. However, beyond the use of fully optimized two-particle correlation
functions, there has been little study of simple alternatives that can correct
this defect. In this work we show that the remedy is surprisingly simple. When
a shadow wavefunction with an inverse seventh power particle-particle
correlation function is used to study $^4$He, it gives a correctly peaked
radial distribution function, lowers the energy at all liquid and solid
densities, and produces an excellent equation of state.

</DOC>
<DOC>
<DOCNO> 11230 </DOCNO>
Long-range interacting classical systems: universality in mixing


  Through molecular dynamics, we study the $d=2,3$ classical model of $N$
coupled rotators (inertial XY model) assuming a coupling constant which decays
with distance as $r_{ij}^{-\alpha}$ ($\alpha \ge 0$). The total energy $<H>$ is
asymptotically $\propto N {\tilde N}$ with ${\tilde N} \equiv
[N^{1-\alpha/d}-(\alpha/d)]/[1-\alpha/d]$, hence the model is thermodynamically
extensive if $\alpha/d>1$ and nonextensive otherwise. We numerically show that,
for energies above some threshold, the (appropriately scaled) maximum Lyapunov
exponent is $\propto N^{-\kappa}$ where $\kappa$ is an {\it universal} (one and
the same for $d=1,2$ and 3, and all energies) function of $\alpha/d$, which
monotonically decreases from 1/3 to zero when $\alpha/d$ increases from 0 to 1,
and identically vanishes above 1. These features are consistent with the
nonextensive statistical mechanics scenario, where thermodynamic extensivity is
associated with {\it exponential} mixing in phase space, whereas {\it weaker}
(possibly {\it power-law} in the present case) mixing emerges at the $N \to
\infty$ limit whenever nonextensivity is observed.

</DOC>
<DOC>
<DOCNO> 179029 </DOCNO>
Single photons from Pb+Pb collisions at CERN SPS, QGP vs. hadronic gas


  In a hydrodynamic model, we have analysed the direct photon data obtained by
the WA98 collaboration in 158 A GeV Pb+Pb collisions at CERN SPS. The
transverse expansion of the system was taken into account. Two scenarios (i)
formation of quark-gluon plasma and (ii) formation of hot hadronic gas were
considered. Equally well description to the data were obtained in both the
scenarios. However, hadronic gas scenario require very high initial temperature
($\sim$ 300 MeV) and it is difficult to conceive existence of hadron gas at
that high temperature. If the hadronic fluid has small radial velocity
(0.2c-0.3c) initially, the data are well explained in the hadronic gas scenario
with reasonable initial temperatures.

</DOC>
<DOC>
<DOCNO> 101278 </DOCNO>
Linking numbers and boundaries of varieties


  The intersection index at a common point of two analytic varieties of
complementary dimensions in $\Bbb C^n$ is positive. This observation, which has
been called a ``cornerstone'' of algebraic geometry ([GH, p.~62]), is a simple
consequence of the fact that analytic varieties carry a natural orientation.
Recast in terms of linking numbers, it is our principal motivation. It implies
the following: Let $M$ be a smooth oriented compact 3-manifold in $\Bbb C^3$.
Suppose that $M$ bounds a bounded complex 2-variety $V$. Here ``bounds'' means,
in the sense of Stokes' theorem, i.e., that ${b[V]}={[M]}$ as currents. Let $A$
be an algebraic curve in $\Bbb C^3$ which is disjoint from M. Consider the
linking number ${\rm link}(M,A)$ of $M$ and $A$. Since this linking number is
equal to the intersection number (i.e. the sum of the intersection indices) of
$V$ and $A$, by the positivity of these intersection indices, we have ${\rm
link}(M,A) \geq 0$. The linking number will of course be 0 if $V$ and $A$ are
disjoint. (As $A$ is not compact, this usage of ``linking number'' will be
clarified later.) This reasoning shows more generally that ${\rm link}(M,A)
\geq 0$ if $M$ bounds a positive holomorphic 2-chain. Recall that a {\it
holomorphic $k$-chain} in $\Omega \subseteq \Bbb C^n$ is a sum $\sum n_j [V_j]$
where $\{V_j\}$ is a locally finite family of irreducible $k$-dimensional
subvarieties of $\Omega$ and $n_j \in \Bbb Z$ and that the holomorphic 2-chain
is {\it positive} if $n_j >0$ for all $j$. Our first result is that,
conversely, the nonnegativity of the linking number characterizes boundaries of
positive holomorphic 2-chains.

</DOC>
<DOC>
<DOCNO> 169852 </DOCNO>
Spontaneous decay in the presence of dispersing and absorbing bodies:


  A formalism for studying spontaneous decay of an excited two-level atom in
the presence of dispersing and absorbing dielectric bodies is developed. An
integral equation, which is suitable for numerical solution, is derived for the
atomic upper-state-probability amplitude. The emission pattern and the power
spectrum of the emitted light are expressed in terms of the Green tensor of the
dielectric-matter formation including absorption and dispersion. The theory is
applied to the spontaneous decay of an excited atom at the center of a
three-layered spherical cavity, with the cavity wall being modeled by a
band-gap dielectric of Lorentz type. Both weak coupling and strong coupling are
studied, the latter with special emphasis on the cases where the atomic
transition is (i) in the normal-dispersion zone near the medium resonance and
(ii) in the anomalous-dispersion zone associated with the band gap. In a
single-resonance approximation, conditions of the appearance of Rabi
oscillations and closed solutions to the evolution of the atomic state
population are derived, which are in good agreement with the exact numerical
results.

</DOC>
<DOC>
<DOCNO> 14092 </DOCNO>
Shear response of a smectic film stabilized by an external field


  The response of a field-stabilized two-dimensional smectic to shear stress is
discussed. Below a critical temperature the smectic film exhibits elastic
response to an infinitesimal shear stress normal to the layering. At finite
stresses free dislocations nucleate and relax the applied stress. The coupling
of the dislocation current to the stress results in non-newtonian viscous flow.
The flow profile in a channel geometry is shown to change qualitatively from a
power-law dependence to a Poiseuille-like profile opon increasing the pressure
head.

</DOC>
<DOC>
<DOCNO> 68666 </DOCNO>
On decay of large amplitude bubble of disoriented chiral condensate


  The time evolution of initially formed large amplitude bubble of disoriented
chiral condensate (DCC) is studied. It is found that the evolution of this
object may have a relatively long pre-decay stage. Simple explanation of such
delay of the DCC bubble decay is given. This delay is related to the existence
of the approximate solutions of multi-soliton type of the corresponding radial
sine-Gordon equation in (3+1) dimensions at large bubble radius.

</DOC>
<DOC>
<DOCNO> 7871 </DOCNO>
Electron states in a one-dimensional random binary alloy


  We present a model for alloys of compound semiconductors by introducing a
one-dimensional binary random system where impurities are placed in one
sublattice while host atoms lie on the other sublattice. The source of disorder
is the stochastic fluctuation of the impurity energy from site to site.
Although the system is one-dimensional and random, we demonstrate analytical
and numerically the existence of extended states in the neighborhood of a given
resonant energy, which match that of the host atoms.

</DOC>
<DOC>
<DOCNO> 123093 </DOCNO>
Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) -


  The Catalogue, available at the Centre de Donn\'ees Stellaires de Strasbourg,
consists of 13573 records concerning the results obtained from different
methods for 7778 stars, reported in the literature. The following data are
listed for each star: identifications, apparent magnitude, spectral type,
apparent diameter in arcsec, absolute radius in solar units, method of
determination, reference, remarks. Comments and statistics obtained from CADARS
are given.

</DOC>
<DOC>
<DOCNO> 150799 </DOCNO>
UV/IR Mixing for Noncommutative Complex Scalar Field Theory, II


  We consider noncommutative analogs of scalar electrodynamics and N=2 D=4 SUSY
Yang-Mills theory. We show that one-loop renormalizability of noncommutative
scalar electrodynamics requires the scalar potential to be an anticommutator
squared. This form of the scalar potential differs from the one expected from
the point of view of noncommutative gauge theories with extended SUSY
containing a square of commutator. We show that fermion contributions restore
the commutator in the scalar potential. This provides one-loop
renormalizability of noncommutative N=2 SUSY gauge theory. We demonstrate a
presence of non-integrable IR singularities in noncommutative scalar
electrodynamics for general coupling constants. We find that for a special
ratio of coupling constants these IR singularities vanish. Also we show that IR
poles are absent in noncommutative N=2 SUSY gauge theory.

</DOC>
<DOC>
<DOCNO> 122803 </DOCNO>
Particle injection and reacceleration in clusters of galaxies and the


  We calculate the energy distribution of the relativistic particles injected
in the ICM during a phase of reacceleration of the relativistic particles in
the cluster volume. We apply our results to the case of the Coma cluster in
which recent merging activity and the presence of the radio halo may suggest
that reacceleration processes are efficient. We find that the electron
population injected in the central part of the cluster by the head-tail radio
galaxy NGC 4869 may account for a large fraction, if not all, of the detected
EUV excess via inverse Compton scattering of the cosmic microwave background
(CMB) photons. If radio haloes are powered by reacceleration mechanisms active
in the cluster volume, moderate non-thermal EUV excesses (of order of $\sim 1-5
\cdot 10^{42}$erg s^{-1}) should be a common feature of clusters containing
powerful head-tail radio galaxies and/or AGNs.

</DOC>
<DOC>
<DOCNO> 116455 </DOCNO>
Transition from the Couette-Taylor system to the plane Couette system


  We discuss the flow between concentric rotating cylinders in the limit of
large radii where the system approaches plane Couette flow. We discuss how in
this limit the linear instability that leads to the formation of Taylor
vortices is lost and how the character of the transition approaches that of
planar shear flows. In particular, a parameter regime is identified where
fractal distributions of life times and spatiotemporal intermittency occur.
Experiments in this regime should allow to study the characteristics of shear
flow turbulence in a closed flow geometry.

</DOC>
<DOC>
<DOCNO> 10969 </DOCNO>
Phenomenological model for magnetotransport in a multi-orbital system


  By means of the Boltzmann equation, we have calculated some magnetotransport
quantities for the layered multi-orbital compound Sr$_2$RuO$_4$. The Hall
coefficient, the magnetoresistance and the in-plane resistivity have been
determined taking into account the Fermi surface curvature and different time
collisions for the electrons in the $t_{2g}$ bands. A consistent explanation of
the experimental results has been obtained assuming different relaxation rates
for the in-plane transport with and without an applied magnetic field,
respectively.

</DOC>
<DOC>
<DOCNO> 170013 </DOCNO>
Spatially Encoded Pseudo-Pure States for NMR Quantum Information


  Quantum information processing by liquid-state NMR spectroscopy uses
pseudo-pure states to mimic the evolution and observations on true pure states.
A new method of preparing pseudo-pure states is described, which involves the
selection of the spatially labeled states of an ancilla spin with which the
spin system of interest is correlated. This permits a general procedure to be
given for the preparation of pseudo-pure states on any number of spins, subject
to the limitations imposed by the loss of signal from the selected subensemble.
The preparation of a single pseudo-pure state is demonstrated by carbon and
proton NMR on 13C-labeled alanine. With a judicious choice of magnetic field
gradients, the method further allows encoding of up to 2^N pseudo-pure states
in independent spatial modes in an N+1 spin system. Fast encoding and decoding
schemes are demonstrated for the preparation of four such spatially labeled
pseudo-pure states.

</DOC>
<DOC>
<DOCNO> 9751 </DOCNO>
Limits of validity for a semiclassical mean-field two-fluid model for


  We reinvestigate the Bose-Einstein condensation (BEC) thermodynamics of a
weakly interacting dilute Bose gas under the action of a trap using a
semiclassical two-fluid mean-field model in order to find the domain of
applicability of the model. Such a model is expected to break down once the
condition of diluteness and weak interaction is violated. We find that this
breakdown happens for values of coupling and density near the present
experimental scenario of BEC. With the increase of the interaction coupling and
density the model may lead to unphysical results for thermodynamic observables.

</DOC>
<DOC>
<DOCNO> 8254 </DOCNO>
Electronic transport through a local state linearly coupled to phonon


  A resolvent formalism is applied to the problem of inelastic scattering of an
electron linearly coupled to a set of phonon modes. It is shown how the many
phonon mode coupling and excitation can be reduced to a single phonon mode
description, consistent with other approaches to the phenomenon of inelastic
tunneling in heterostructures. A unifying connection is made with the phenomena
of resonant electron scattering through molecules in the gas phase and of
tunneling of electrons through adsorbates in scanning tunneling microscopy.

</DOC>
<DOC>
<DOCNO> 85659 </DOCNO>
Chemical equilibrium and stable stratification of a multi-component


  A general thermodynamic argument shows that multi-component matter in full
chemical equilibrium, with uniform entropy per baryon, is generally stably
stratified. This is particularly relevant for neutron stars, in which the
effects of entropy are negligible compared to those of the equilibrium
composition gradient established by weak interactions. It can therefore be
asserted that, regardless of the uncertainties in the equation of state of
dense matter, neutron stars are stably stratified. This has important,
previously discussed consequences for their oscillation modes, magnetic field
evolution, and internal angular momentum transport.

</DOC>
<DOC>
<DOCNO> 122317 </DOCNO>
Emission Line Properties of the Large Bright Quasar Survey


  We present measurements of the optical/UV emission lines for a large
homogeneous sample of 993 quasars from the Large Bright Quasar Survey. Our
largely automated technique accounts for continuum breaks and galactic
reddening, and we perform multicomponent fits to emission line profiles,
including the effects of blended iron emission, and of absorption lines both
galactic and intrinsic. Here we describe the fitting algorithm and present the
results of line fits to the LBQS sample, including upper limits to line
equivalent widths when warranted. The distribution of measured line parameters,
principally equivalent width and FWHM, are detailed for a variety of lines,
including upper limits. We thus initiate a large-scale investigation of
correlations between the high energy continuum and emission lines in quasars,
to be extended to complementary samples using similar techniques. High quality,
reproducible measurements of emission lines for uniformly selected samples will
advance our understanding of active galaxies, especially in a new era of large
surveys selected by a variety of complementary methods.

</DOC>
<DOC>
<DOCNO> 8994 </DOCNO>
Swelling-collapse transition of self-attracting walks


  We study the structural properties of self-attracting walks in d dimensions
using scaling arguments and Monte Carlo simulations. We find evidence for a
transition analogous to the \Theta transition of polymers. Above a critical
attractive interaction u_c, the walk collapses and the exponents \nu and k,
characterising the scaling with time t of the mean square end-to-end distance
<R^2> ~ t^{2 \nu} and the average number of visited sites <S> ~ t^k, are
universal and given by \nu=1/(d+1) and k=d/(d+1). Below u_c, the walk swells
and the exponents are as with no interaction, i.e. \nu=1/2 for all d, k=1/2 for
d=1 and k=1 for d >= 2. At u_c, the exponents are found to be in a different
universality class.

</DOC>
<DOC>
<DOCNO> 170664 </DOCNO>
Decoherence of a Pointer by a Gas Reservoir


  We study the effect of the environment on the process of the measurement of a
state of a microscopic spin half system. The measuring apparatus is a heavy
particle, whose center of mass coordinates can be considered at the end of the
measurement as approximately classical, and thus can be used as a pointer. The
state of the pointer, which is the result of its interaction with the spin, is
transformed into a mixed state by the coupling of the pointer to the
environment. The environment is considered to be a gas reservoir, whose
particles interact with the pointer. This results in a Fokker-Planck equation
for the reduced density matrix of the pointer. The solution of the equation
shows that the quantum coherences, which are characteristic to the entangled
state between the probabilities to find the pointer in one of two positions,
decays exponentially fast in time. We calculate the exponential decay function
of this decoherence effect, and express it in terms of the parameters of the
model.

</DOC>
<DOC>
<DOCNO> 152102 </DOCNO>
Compositeness of gauge boson and asymptotic freedom in non-abelian gauge


  In order to investigate the composite gauge field, we consider the
compositeness condition (i.e. renormalization constant $Z_3=0$) in the general
non-abelian gauge field theory. We calculate $Z_3$ at the next-to-leading order
in $1/N_f$ expansion ($N_f$ is the number of fermion flavors), and obtain the
expression to the gauge coupling constant through the compositeness condition.
Then the gauge coupling constant is proportional to $1/\sqrt{4N_f
T(R)-11C_2(G)}$ where T(R) is the index for a representation R of gauge group
G, and $C_2(G)$ is the quadratic Casimir. It is found that the gauge boson
compositeness take place only when $N_f T(R)/C_2(G) > 11/4$, in which the
asymptotic freedom in the non-abelian gauge field theory fails.

</DOC>
<DOC>
<DOCNO> 71694 </DOCNO>
Electroweak Radiative Corrections to Off-Shell W-Pair Production


  We briefly describe the RacoonWW approach to calculate radiative corrections
to e+ e- -> W W -> 4 fermions and present numerical results for the total
W-pair production cross section at LEP2.

</DOC>
<DOC>
<DOCNO> 12298 </DOCNO>
Playing a quantum game with a corrupted source


  The quantum advantage arising in a simplified multi-player quantum game, is
found to be a disadvantage when the game's qubit-source is corrupted by a noisy
"demon". Above a critical value of the corruption-rate, or noise-level, the
coherent quantum effects impede the players to such an extent that the optimal
choice of game changes from quantum to classical.

</DOC>
<DOC>
<DOCNO> 100764 </DOCNO>
Further Representations of the Canonical Commutation Relations


  We construct a new class of representations of the canonical commutation
relations, which generalizes previously known classes. We perturb the
infinitesimal generator of the initial Fock representation (i.e. the free
quantum field) by a function of the field which is square-integrable with
respect to the associated Gaussian measure. We characterize which such
perturbations lead to representations of the canonical commutation relations.
We provide conditions entailing the irreducibility of such representations,
show explicitly that our class of representations subsumes previously studied
classes, and give necessary and sufficient conditions for our representations
to be unitarily equivalent, resp. quasi-equivalent, with Fock, coherent or
quasifree representations.

</DOC>
<DOC>
<DOCNO> 101218 </DOCNO>
The Hodge Conjecture for general Prym varieties


  The space of Hodge cycles of the general Prym variety is proved to be
generated by its Neron-Severi group.

</DOC>
<DOC>
<DOCNO> 120265 </DOCNO>
Face-on Dust Disks in Galaxies with Optical Jets


  The presence of optical synchrotron jets in radio galaxies is relatively
rare. Here, we show that of the nearest five FR-I 3CR radio galaxies showing
optical jets, {\it four} show evidence for almost circular, presumably face-on,
dust disks. This is strong support for the two-fold idea that (\romannumeral1)
jets emerge close to perpendicular to inner gas disks and (\romannumeral2)
optical non-thermal synchrotron emission is seen only when the jet points
towards the observer. The implied critical angle to the line-of-sight is
approximately 30 - $40^{\circ}$, i.e. if the angle of the jet to the
line-of-sight is less than about $40^{\circ}$ we see an optical jet. The
corresponding relativisitic $\gamma$ factor is $\approx 1.5$ which is
consistent with current observations of jet proper motion that show a range up
to $\gamma \sim 6$ for M87. The relatively low speeds implied by $\gamma
\approx 1.5$ may be due to a global deceleration of the jet as in unified
theories, or else to stratification within the jet. Unresolved nuclei are
common in the optical. Their luminosities are also consistent with the beaming
concept when compared to inclination inferred from the dust lanes. The disk
sizes are typically several hundred parsecs, to kiloparsec size. The galaxy
with an optical jet that does not show a face-on disk, M87, instead has more
complex radial dust and ionized gas filaments.

</DOC>
<DOC>
<DOCNO> 70465 </DOCNO>
Fermion zero-modes on brane-worlds


  We study localization of bulk fermions on a brane with inclusion of
Yang-Mills and scalar backgrounds in higher dimensions and give the conditions
under which localized chiral fermions can be obtained.

</DOC>
<DOC>
<DOCNO> 72063 </DOCNO>
Quark-meson coupling model with short-range quark-quark interactions


  Short-range quark-quark correlations are introduced into the quark-meson
coupling (QMC) model phenomenologically. We study the effect of the
correlations on the structure of the nucleon in dense nuclear matter. With the
addition of correlations, the saturation curve for symmetric nuclear matter is
much improved at high density.

</DOC>
<DOC>
<DOCNO> 123014 </DOCNO>
Cluster abundance and large scale structure


  We use the presently observed number density of large X-ray clusters and the
linear mass power spectra to constrain $\sigma_8$ and the redshift distortion
parameter $\beta$, in both OCDM and $\Lambda$CDM models. The best fit to the
observed mass power spectra gives $n=0.84\pm 0.67$ and
$\Gamma=0.27^{+0.42}_{-0.16}$, with the theoretically expected degeneracy
$\Gamma'=0.247\Gamma\exp(1.4n)=0.220^{+0.036}_{-0.031}$ (all at 95% confidence
level). Based on this, we then calculate the cluster-abundance-normalized
$\sigma_8$, using different models of mass function: Press & Schechter (1974),
Sheth & Tormen (1999), and Lee & Shandarin (1999). The $\sigma_8$ based on the
non-spherical-collapse models (ST & LS) are significantly lower, mainly due to
the larger mass function within the scale range of our interest. In particular,
we found $\sigma_{8{\rm (ST+LS)}}=0.477\Omega_{\rm m0}^\alpha$, where
$\alpha=-0.3-0.17\Omega_{\rm m0}^{0.34}-0.13\Omega_{\Lambda 0}$. We also derive
the probability distribution function of cluster formation redshift using the
Lacey-Cole formalism (1993), but with modifications to incorporate
non-spherical collapse. The uncertainties in our $\sigma_8$ are mainly
contributed from the normalization in the virial mass-temperature relation. We
also obtain for the IRAS galaxies $\sigma_{8\rm (I)}=0.78\pm 0.06$ (at 95%
confidence level), and found $\beta_{\rm I(ST+LS)}=0.613\Omega_{\rm
m0}^{0.24-0.16(\Omega_{\rm m0}+\Omega_{\Lambda 0})}$. This is more consistent
with the recent observations than the result based on the PS formalism.

</DOC>
<DOC>
<DOCNO> 117950 </DOCNO>
Where Do Cooling Flows Cool?


  Although only about 5 percent of the total baryonic mass in luminous
elliptical galaxies is in the form of cooled interstellar gas, it is
concentrated within the optical effective radius r_e where it influences the
local dynamical mass. The mass of cooled gas must be spatially distributed
since it greatly exceeds the masses of central black holes. We explore here the
proposition that a population of low mass, optically dark stars is created from
the cooled gas. We consider a wide variety of radial distributions for the
interstellar cooling, but only a few are consistent with observed X-ray surface
brightness profiles. In a region of concentrated interstellar cooling, the
X-ray emission can exceed that observed, suggesting the presence of additional
support by magnetic stresses or non-thermal pressure. In general we find that
the mass of cooled gas contributes significantly to stellar dynamical mass to
light ratios which vary with galactic radius. If the stars formed from cooled
interstellar gas are optically luminous, their influence on the the mass to
light ratio would be reduced. The mass of cooled gas inside r_e is sensitive to
the rate that old stars lose mass, which is nearly independent of the initial
mass function of the old stellar population.

</DOC>
<DOC>
<DOCNO> 117356 </DOCNO>
Multiple Outflows in AFGL 2688


  We present high resolution (1.1x0.9'') imaging of the proto-planetary nebula
AFGL 2688 in the CO (J=2-1) line using the IRAM interferometer. The
observations reveal with unprecedented detail the structure and the kinematics
of the gas ejected by the star over the past few hundred years and exemplify
the mechanism by which point symmetries are imprinted on the structure of
planetary nebulae at early stages of their formation.

</DOC>
<DOC>
<DOCNO> 12165 </DOCNO>
Analysis of g_2 for the cold-collision frequency shift in the hydrogen


  We compute an approximate set of longitudinal quasiparticle modes for a
hydrogen condensate as produced in the MIT experiments. An expansion in
quasiparticles using a simple one-dimensional Bogoliubov picture shows however
that at the high temperatures (\approx 44muK) and in the very shallow trap
employed (omega_z = 2\pi\times 10.2Hz) the contribution to the density from the
quasiparticles is about 20% of that from the condensate mode, leading to an
effective $ g_2(x,x) which varies between 1 and 3 depending on the position in
the condensate.

</DOC>
<DOC>
<DOCNO> 8694 </DOCNO>
Heat Conduction and Charge Ordering in Perovskite Manganites, Nickelates


  We discuss heat transport in hole-doped manganites, nickelates and cuprates
for which real-space charge ordering has been observed. We survey the thermal
transport response to charge order in the various materials and the associated
structural modifications, particularly distortions of the metal-oxygen
polyhedra associated with localized charge, that may be a principal source of
phonon damping.

</DOC>
<DOC>
<DOCNO> 170183 </DOCNO>
Stochastic limit approximation for rapidly decaying systems


  The stochastic limit approximation method for ``rapid'' decay is presented,
where the damping rate \gamma is comparable to the system frequency \Omega,
i.e., \gamma \sim \Omega, whereas the usual stochastic limit approximation is
applied only to the weak damping situation \gamma << \Omega. The key formulas
for rapid decay are very similar to those for weak damping, but the dynamics is
quite different. From a microscopic Hamiltonian, the spin-boson model, a Bloch
equation containing two independent time scales is derived. This is a useful
method to extract the minimal dissipative dynamics at high temperature kT >>
\hbar\Omega and the master equations obtained are of the Lindblad form even for
the Caldeira-Leggett model. The validity of the method is confirmed by
comparing the master equation derived through this method with the exact one.

</DOC>
<DOC>
<DOCNO> 101596 </DOCNO>
Mirror symmetry without corrections


  We give geometric explanations and proofs of various mirror symmetry
conjectures for $T^{n}$-invariant Calabi-Yau manifolds when instanton
corrections are absent. This uses fiberwise Fourier transformation together
with base Legendre transformation.
  We discuss mirror transformations of
  (i) moduli spaces of complex structures and complexified symplectic
structures, $H^{p,q}$'s, Yukawa couplings;
  (ii) sl(2)xsl(2)-actions;
  (iii) holomorphic and symplectic automorphisms and
  (iv) A- and B-connections, supersymmetric A- and B-cycles, correlation
functions.
  We also study (ii) for $T^{n}$-invariant hyperkahler manifolds.

</DOC>
<DOC>
<DOCNO> 70754 </DOCNO>
The tauola-photos_F environment for versioning the TAUOLA and PHOTOS


  We present the system for versioning two packages: the TAUOLA of tau lepton
decay and PHOTOS for radiative corrections in decays. The following features
can be chosen in automatic or semi-automatic way: (1) format of the common
block HEPEVT; (2) version of the physics input (for TAUOLA): as published, as
initialized by CLEO collaboration, as initialized by ALEPH collaboration (it is
suggested to use this version only with the help of the collaboration advice);
(3) type of application: stand-alone, universal interface through HEPEVT,
interface for KKMC Monte Carlo; (4) random number generators; (5) compiler
options.

</DOC>
<DOC>
<DOCNO> 69126 </DOCNO>
Prospects of Squark & Slepton searches at a Gamma Gamma Collider


  We examine the prospects of detecting sfermions at a gamma gamma collider.
Once produced, a slepton can decay into a pair of quarks (jets) through
R-parity violating interactions. Similarly, a squark may decay into a
lepton-quark pair. Analyzing the corresponding Standard Model backgrounds,
namely 4-jet and dilepton plus dijet final states respectively, we show that
the sfermion can be detected almost right upto the kinematic limit and its mass
determined to a fair degree of accuracy. Similar statements also hold for
nonsupersymmetric leptoquarks and diquarks.

</DOC>
<DOC>
<DOCNO> 84437 </DOCNO>
Signature Change and Clifford Algebras


  Given the real Clifford algebra of a quadratic space with a given signature,
we define a new product in this structure such that it simulates the Clifford
product of a quadratic space with another signature different from the original
one. Among the possible applications of this new product, we use it in order to
write the minkowskian Dirac equation over the euclidean spacetime and to define
a new duality operation in terms of which one can find self-dual and
anti-self-dual solutions of gauge fields over Minkowski spacetime analogous to
the ones over Euclidean spacetime and without needing to complexify the
original real algebra.

</DOC>
<DOC>
<DOCNO> 84802 </DOCNO>
Casimir energy and variational methods in AdS spacetime


  Following the subtraction procedure for manifolds with boundaries, we
calculate by variational methods, the Schwarzschild-Anti-de Sitter and the
Anti-de Sitter space energy difference. By computing the one loop approximation
for TT tensors we discover the existence of an unstable mode at zero
temperature, which can be stabilized by the boundary reduction method.
Implications on a foam-like space are discussed.

</DOC>
<DOC>
<DOCNO> 119550 </DOCNO>
On the Correlation Between CO Absorption and Far-Ultraviolet Non-Linear


  A sample of 59 sight lines to reddened Galactic OB stars was examined for
correlations of the strength of the CO Fourth Positive (A - X) absorption band
system with the ultraviolet interstellar extinction curve parameters. We used
archival high-dispersion NEWSIPS IUE spectra to measure the CO absorption for
comparison to parametric fits of the extinction curves from the literature. A
strong correlation with the non-linear far-UV curvature term was found with
greater absorption, normalized to E(B-V), being associated with more curvature.
A weaker trend with the linear extinction term was also found. Mechanisms for
enhancing CO in dust environments exhibiting high non-linear curvature are
discussed.

</DOC>
<DOC>
<DOCNO> 67686 </DOCNO>
The Components of the $\gamma^*\gamma^*$ Cross Section


  We extend our previous treatment of $\gamma^*p$ cross section based on
Gribov's hypothesis to the case of photon-photon scattering. With the aid of
two parameters, determined from experimental data, we separate the interactions
into two categories corresponding to short ("soft") and long ("hard") distance
processes. The photon-photon cross section, thus, receives contributions from
three sectors, soft-soft, hard-hard and hard-soft. The additive quark model is
used to describe the soft-soft sector, pQCD the hard-hard sector, while the
hard-soft sector is determined by relating it to the $\gamma^{*}$p system. We
calculate and display the behaviour of the total photon-photon cross section
and it's various components and polarizations for different values of energy
and virtuality of the two photons, and discuss the significance of our results.

</DOC>
<DOC>
<DOCNO> 68508 </DOCNO>
Gluon Fragmentation to Gluonium


  The fragmentation of gluons to gluonium states is analyzed qualitatively in
the non-perturbative region. The convolution of this mechanism with
perturbative gluon radiation leaves us with a hard component in the
fragmentation of gluon to gluonium.

</DOC>
<DOC>
<DOCNO> 8614 </DOCNO>
Comparison of two methods for calculating nucleation rates


  First-order phase transitions that proceed via nucleation of bubbles are
described by the homogeneous nucleation theory of Langer. The nucleation rate
is one of the most interesting parameters of these transitions. In previous
works we have computed nucleation rates with two different methods: (A)
employing coarse-grained potentials; (B) by means of a saddle-point
approximation, using dimensionally regularized field theory. In this article we
compare the results of the two approaches in order to test their reliability
and to determine the regions of applicability. We find a very good agreement.

</DOC>
<DOC>
<DOCNO> 99898 </DOCNO>
SU(3) Symmetry and Scissors Mode Vibrations in Nuclei


  We show that a nearly perfect SU(3) symmetry emerges from an extended
Projected Shell Model. Starting from a deformed potential we construct separate
bases for neutron and proton collective rotational states by exact angular
momentum projection. These rotational states are then coupled by diagonalizing
a residual pairing plus quadrupole interaction. The states obtained exhibit a
one-to-one correspondence with an SU(3) spectrum up to high angular momentum
and excitation, and their wave functions have a near-maximal overlap with the
SU(3) states. They can also be classified as rotational bands built on
spin-1$\hbar$ phonon excitations, which may correspond to a geometrical
scissors mode and its generalizations. This work is a direct demonstration that
numerical angular momentum projection theory extends the Elliott's original
idea to heavy nuclear systems.

</DOC>
<DOC>
<DOCNO> 11342 </DOCNO>
Collective excitation frequencies of a Bose - Einstein condensate with


  We investigate collective excitations of an atomic Bose-Einstein condensate
in a recently discovered regime [D.O'Dell et al., Phys. Rev. Lett. 84, 5687
(2000)] of a balance between electromagnetically induced $1/r$ attraction and a
short-range interatomic repulsion. The corresponding frequencies for monopole,
dipole, and quadrupole modes are calculated numerically in the zero temperature
case.

</DOC>
<DOC>
<DOCNO> 13700 </DOCNO>
Inherent-Structure Dynamics and Diffusion in Liquids


  The self-diffusion constant D is expressed in terms of transitions among the
local minima of the potential (inherent structure, IS) and their correlations.
The formulae are evaluated and tested against simulation in the supercooled,
unit-density Lennard-Jones liquid. The approximation of uncorrelated
IS-transition (IST) vectors, D_{0}, greatly exceeds D in the upper temperature
range, but merges with simulation at reduced T ~ 0.50. Since uncorrelated IST
are associated with a hopping mechanism, the condition D ~ D_{0} provides a new
way to identify the crossover to hopping. The results suggest that theories of
diffusion in deeply supercooled liquids may be based on weakly correlated IST.

</DOC>
<DOC>
<DOCNO> 9060 </DOCNO>
Stochastic Aggregation: Rate Equations Approach


  We investigate a class of stochastic aggregation processes involving two
types of clusters: active and passive. The mass distribution is obtained
analytically for several aggregation rates. When the aggregation rate is
constant, we find that the mass distribution of passive clusters decays
algebraically. Furthermore, the entire range of acceptable decay exponents is
possible. For aggregation rates proportional to the cluster masses, we find
that gelation is suppressed. In this case, the tail of the mass distribution
decays exponentially for large masses, and as a power law over an intermediate
size range.

</DOC>
<DOC>
<DOCNO> 10670 </DOCNO>
Decoherence and long-lived Schroedinger cats in BEC


  We consider quantum superposition states in Bose-Einstein condensates. A
decoherence rate for the Schr\"odinger cat is calculated and shown to be a
significant threat to this macroscopic quantum superposition of BEC's. An
experimental scenario is outlined where the decoherence rate due to the thermal
cloud is dramatically reduced thanks to trap engineering and "symmetrization"
of the environment. We show that under the proposed scenario the Schroedinger
cat belongs to an approximate decoherence-free pointer subspace. This paper is
a simplified and more pedagogical version of our previous work, Phys.Rev. A62,
13607 (2000).

</DOC>
<DOC>
<DOCNO> 118754 </DOCNO>
Two-dimensional models of hydrodynamical accretion flows into black


  We present a systematic numerical study of two-dimensional axisymmetric
accretion flows around black holes. The flows have no radiative cooling and are
treated in the framework of the hydrodynamical approximation. The models
calculated in this study cover the large range of the relevant parameter space.
There are four types of flows, determined by the values of the viscosity
parameter $\alpha$ and the adiabatic index $\gamma$: convective flows,
large-scale circulations, pure inflows and bipolar outflows. Thermal conduction
introduces significant changes to the solutions, but does not create a new flow
type. Convective accretion flows and flows with large-scale circulations have
significant outward-directed energy fluxes, which have important implications
for the spectra and luminosities of accreting black holes.

</DOC>
<DOC>
<DOCNO> 11953 </DOCNO>
Pressure-Induced Interlinking of Carbon Nanotubes


  We predict new forms of carbon consisting of one and two dimensional networks
of interlinked single wall carbon nanotubes, some of which are energetically
more stable than van der Waals packing of the nanotubes on a hexagonal lattice.
These interlinked nanotubes are further transformed with higher applied
external pressures to more dense and complicated stable structures, in which
curvature-induced carbon sp$^{3}$ re-hybridizations are formed. We also discuss
the energetics of the bond formation between nanotubes and the electronic
properties of these predicted novel structures.

</DOC>
<DOC>
<DOCNO> 68280 </DOCNO>
Gauge fields - strings duality and the loop equation


  We explore gauge fields - strings duality by means of the loop equations and
the zigzag symmetry. The results are striking and incomplete. Striking -
because we find that the string ansatz proposed in [A.M. Polyakov,
hep-th/9711002] satisfies gauge theory Schwinger-Dyson equations precisely at
the critical dimension D=4. Incomplete - since we get these results only in the
WKB approximation and only for a special class of contours. The ways to go
beyond these limitations and in particular the OPE for operators defined on the
loop are also discussed.

</DOC>
<DOC>
<DOCNO> 71482 </DOCNO>
Prospects of Discovering the Higgs Boson at the Tevatron


  We carry out an event generator based study to evaluate the usefulness of the
the exclusive signature ``$e^\pm (\mu^\pm) + 2$ bottom jets'' in discovering
the Higgs boson at the Tevatron.
 Using an event generator, we show that with enough luminosity, one should be
able to detect the Higgs boson up to the mass of about 130 GeV. We consider a
slightly modified version of the above signature that includes one extra jet.
 This new signature is more useful because it increases the number of signal
events significantly.

</DOC>
<DOC>
<DOCNO> 11180 </DOCNO>
Toward an anisotropic atom-atom model for the crystalline phases of the


  We analize two anisotropic atom-atom models used to describe the crystalline
alpha,beta and gamma phases of S8 crystals, the most stable compound of
elemental sulfur in solid phases, at ambient pressure and T<=400 K. The
calculations are performed via a series of classical molecular dynamics (MD)
simulations, with flexible molecular models and using a constant
pressure-constant temperature algorithm for the numerical simulations. All
intramolecular modes that mix with lattice modes, and are therefore relevant on
the onset of structural phase transitions, are taken into account. Comparisons
with experimental data and previous results obtained with an isotropic
atom-atom molecular model are also performed.

</DOC>
<DOC>
<DOCNO> 10230 </DOCNO>
Interface dynamics from experimental data


  A novel algorithm is envisaged to extract the coupling parameters of the
Kardar-Parisi-Zhang (KPZ) equation from experimental data. The method hinges on
the Fokker-Planck equation combined with a classical least-square error
procedure. It takes properly into account the fluctuations of surface height
through a deterministic equation for space correlations. We apply it to the 1+1
KPZ equation and carefully compare its results with those obtained by previous
investigations. Unlike previous approaches, our method does not require large
sizes and is stable under a modification of sampling time of observations.
Shortcomings associated to standard discretizations of the continuous KPZ
equation are also pointed out and possible future perspectives are finally
analyzed.

</DOC>
<DOC>
<DOCNO> 70005 </DOCNO>
Extra dimensions, SN1987a, and nucleon-nucleon scattering data


  One of the strongest constraints on the existence of large, compact,
"gravity-only" dimensions comes from SN1987a. If the rate of energy loss into
these putative extra dimensions is too high, then the neutrino pulse from the
supernova will differ from that actually seen. The dominant mechanism for the
production of Kaluza-Klein gravitons and dilatons in the supernova is via
gravistrahlung and dilastrahlung from the nucleon-nucleon system. In this paper
we compute the rates for these processes in a model-independent way using
low-energy theorems which relate the emissivities to the measured
nucleon-nucleon cross section. This is possible because for soft gravitons and
dilatons the leading contribution to the energy-loss rate is from graphs in
which the gravitational radiation is produced from external nucleon legs.
Previous calculations neglected these mechanisms. We re-evaluate the bounds on
toroidally-compactified "gravity-only" dimensions (GODs), and find that
consistency with the observed SN1987a neutrino signal requires that if there
are two such dimensions then their radius must be less than 1 micron.

</DOC>
<DOC>
<DOCNO> 67784 </DOCNO>
The Electric Dipole Moment and CP Violation in $B \to X_s l^+ l^-$ in


  The constraints of electric dipole moments (EDMs) of electron and neutron on
the parameter space in supergravity (SUGRA) models with nonuniversal gaugino
masses are analyzed. It is shown that with a light sparticle spectrum, the
sufficient cancellations in the calculation of EDMs can happen for all phases
being order of one in the small tan$\beta$ case and all phases but $\phi_{\mu}$
($|\phi_{\mu}| <\sim \pi/6$) order of one in the large tan$\beta$
case. This is in contrast to the case of mSUGRA in which in the parameter space
where cancellations among various SUSY contributions to EDMs happen
$|\phi_{\mu}|$ must be less than $\pi/10$ for small $tan\beta$ and
${\cal{O}}(10^{-2})$ for large $tan\beta$. Direct CP asymmetries and the T-odd
polarization of lepton in $B\to X_s l^+l^-$ are investigated in the models. In
the large tan$\beta$ case, $A_{CP}^2$ and $P_N$ for l=$\mu$ ($\tau$) can be
enhanced by about a factor of ten (ten) and ten (three) respectively compared
to those of mSUGRA.

</DOC>
<DOC>
<DOCNO> 11340 </DOCNO>
Role of the unstable directions in the equilibrium and aging dynamics of


  The connectivity of the potential energy landscape in supercooled atomic
liquids is investigated through the calculation of the instantaneous normal
modes spectrum and a detailed analysis of the unstable directions in
configuration space. We confirm the hypothesis that the mode-coupling critical
temperature is the $T$ at which the dynamics crosses over from free to
activated exploration of configuration space. We also report the observed
changes in the local connectivity of configuration space sampled during aging,
following a temperature jump from a liquid to a glassy state.

</DOC>
<DOC>
<DOCNO> 85132 </DOCNO>
Scattering of massive Dirac fields on the Schwarzschild black hole


  With a generally covariant equation of Dirac fields outside a black hole, we
develop a scattering theory for massive Dirac fields. The existence of modified
wave operators at infinity is shown by implementing a time-dependent
logarithmic phase shift from the free dynamics to offset a long-range mass
term. The phase shift we obtain is a matrix operator due to the existence of
both positive and negative energy wave components.

</DOC>
<DOC>
<DOCNO> 84785 </DOCNO>
Black holes and a scalar field in an expanding universe


  We consider a model of an inhomogeneous universe including a massless scalar
field, where the inhomogeneity is assumed to consist of many black holes. This
model can be constructed by following Lindquist and Wheeler, which has already
been investigated without including scalar field to show that an averaged scale
factor coincides with that of the Friedmann model. In this work we construct
the inhomogeneous universe with an massless scalar field, where we assume that
the averaged scale factor and scalar field are given by those of the Friedmann
model including a scalar field. All of our calculations are carried out in the
framework of Brans-Dicke gravity. In constructing the model of an inhomogeneous
universe, we define the mass of a black hole in the Brans-Dicke expanding
universe which is equivalent to ADM mass if the mass evolves adiabatically, and
obtain an equation relating our mass to the averaged scalar field and scale
factor. As the results we find that the mass has an adiabatic time dependence
in a sufficiently late stage of the expansion of the universe, and that the
time dependence is qualitatively diffenrent according to the sign of the
curvature of the universe: the mass increases decelerating in the closed
universe case, is constant in the flat case and decreases decelerating in the
open case. It is also noted that the mass in the Einstein frame depends on
time. Our results that the mass has a time dependence should be retained even
in the general scalar-tensor gravitiy with a scalar field potential.
Furthermore, we discuss the relation of our results to the uniqueness theorem
of black hole spacetime and gravitational memory effect.

</DOC>
<DOC>
<DOCNO> 13947 </DOCNO>
Evolution and stability of a magnetic vortex in small cylindrical


  The energy of a displaced magnetic vortex in a cylindrical particle made of
isotropic ferromagnetic material (magnetic dot) is calculated taking into
account the magnetic dipolar and the exchange interactions. Under the
simplifying assumption of small dot thickness the closed-form expressions for
the dot energy is written in a non-perturbative way as a function of the
coordinate of the vortex center. Then, the process of losing the stability of
the vortex under the influence of the externally applied magnetic field is
considered. The field destabilizing the vortex as well as the field when the
vortex energy is equal to the energy of a uniformly magnetized state are
calculated and presented as a function of dot geometry. The results (containing
no adjustable parameters) are compared to the recent experiment and are in good
agreement.

</DOC>
<DOC>
<DOCNO> 69492 </DOCNO>
Diffractive Vector Meson Production In A Unified $\kappa$-Factorization


  In the framework of the $\kappa$-factorization approach and on the basis of
recently determined DGSF, we calculated the production rates of ground and
excited (2S and D wave) states of vector mesons and investigated their various
kinematical and spin dependencies. We also addressed the issue of S/D wave
mixing in quarkonia.

</DOC>
<DOC>
<DOCNO> 120804 </DOCNO>
Molecular line study of evolution in protostellar cloud cores


  Two dense dark cloud cores representing different stages of dynamical
evolution were observed in a number of molecular spectral lines. One of the
cores, Cha- MMS1 in the Chamaeleon cloud I contains a Class 0 protostar,
whereas the other, CrA C in the R Coronae Australis cloud, is pre-stellar. We
find that the cores have very different chemical compositions. Cha-MMS1
exhibits characteristics of so-called `early-type' chemistry with high abundan-
ces of carbon-chain molecules such as HC3N, but it also has a large N2H+
abundance, which is expected only to build up at later stages. In contrast,
none of the carbon-chain molecules were detected in CrA C. CrA C has a higher
SO abundance than Cha-MMS1, which implies that it is chemically `older' than
Cha- MMS1. The most striking difference between the two cores is seen in the
HC3N/SO abundance ratio, which is at least three orders of magnitude higher in
Cha-MMS than in CrA C. This result is surprising since starless cores are
usually thought to be chemically younger than star-forming cores. Because of
the high N2H+ abundance, we suggest that Cha-MMS1 represents the `late-time
cyanopolyyne peak'. This would also be a more natural explanation for the
carbon-chain molecules than the `early-time' picture in view of the fact that
the core is presently collapsing to form a star. Thus, the dynamical evolution
in CrA C seems to have been very slow compared with that of Cha-MMS1, and we
discuss possible reasons for this.

</DOC>
<DOC>
<DOCNO> 118145 </DOCNO>
Stellar Iron Abundances at the Galactic Center


  We present measurements of [Fe/H] for six M supergiant stars and three giant
stars within 0.5 pc of the Galactic Center (GC) and one M supergiant star
within 30 pc of the GC. The results are based on high-resolution (lambda /
Delta lambda =40,000) K-band spectra, taken with CSHELL at the NASA Infrared
Telescope Facility.We determine the iron abundance by detailed abundance
analysis,performed with the spectral synthesis program MOOG.The mean [Fe/H] of
the GC stars is determined to be near solar,[Fe/H] = +0.12 $\pm$ 0.22. Our
analysis is a differential analysis, as we have observed and applied the same
analysis technique to eleven cool, luminous stars in the solar neighborhood
with similar temperatures and luminosities as the GC stars. The mean [Fe/H] of
the solar neighborhood comparison stars, [Fe/H] = +0.03 $\pm$ 0.16, is similar
to that of the GC stars. The width of the GC [Fe/H] distribution is found to be
narrower than the width of the [Fe/H] distribution of Baade's Window in the
bulge but consistent with the width of the [Fe/H] distribution of giant and
supergiant stars in the solar neighborhood.

</DOC>
<DOC>
<DOCNO> 119454 </DOCNO>
Skewness as a probe of non-Gaussian initial conditions


  We compute the skewness of the matter distribution arising from non-linear
evolution and from non-Gaussian initial perturbations. We apply our result to a
very generic class of models with non-Gaussian initial conditions and we
estimate analytically the ratio between the skewness due to non-linear
clustering and the part due to the intrinsic non-Gaussianity of the models. We
finally extend our estimates to higher moments.

</DOC>
<DOC>
<DOCNO> 101693 </DOCNO>
Spectra of the Gamma-invariant of uniform modules


  For a ring R, denote by Spec^R_kappa(Gamma) the kappa-spectrum of the
Gamma-invariant of strongly uniform right R-modules. Recent realization
techniques of Goodearl and Wehrung show that Spec^R_{aleph_1}(Gamma) is full
for suitable von Neumann regular algebras R, but the techniques do not extend
to cardinals kappa>aleph_1. By a direct construction, we prove that for any
field F and any regular uncountable cardinal kappa there is an F-algebra R such
that Spec^R_kappa(Gamma) is full. We also derive some consequences for the
complexity of Ziegler spectra of infinite dimensional algebras.

</DOC>
<DOC>
<DOCNO> 8863 </DOCNO>
Electronic Fine Structure in the Electron-Hole Plasma in SrB6


  Electron-hole mixing-induced fine structure in alkaline earth hexaborides
leads to lower energy (temperature) scales, and thus stronger tendency toward
an excitonic instability, than in their doped counterparts (viz.
Ca(1-x)La(x)B(6), x=0.005), which are high Curie temperature, small moment
ferromagnets. Comparison of Fermi surfaces and spectral distributions with de
Haas - van Alphen (dHvA), optical, transport, and tunneling data indicates that
SrB6 remains a fermionic semimetal down to (at least) 5 K, rather than forming
an excitonic condensate. For the doped system the Curie temperature is higher
than the degeneracy temperature.

</DOC>
<DOC>
<DOCNO> 102212 </DOCNO>
Gauge theory and calibrated geometry, I


  The geometry of submanifolds is intimately related to the theory of functions
and vector bundles. It has been of fundamental importance to find out how those
two objects interact in many geometric and physical problems. A typical example
of this relation is that the Picard group of line bundles on an algebraic
manifold is isomorphic to the group of divisors, which is generated by
holomorphic hypersurfaces modulo linear equivalence. A similar correspondence
can be made between the K-group of sheaves and the Chow ring of holomorphic
cycles. There are two more very recent examples of such a relation. The mirror
symmetry in string theory has revealed a deeper phenomenon involving special
Lagrangian cycles (cf. [SYZ]). On the other hand, C. Taubes has shown that the
Seiberg-Witten invariant coincides with the Gromov-Witten invariant on any
symplectic 4-manifolds.
  In this paper, we will show another natural interaction between Yang-Mills
connections, which are critical points of a Yang-Mills action associated to a
vector bundle, and minimal submanifolds, which have been studied extensively
for years in classical differential geometry and the calculus of variations.

</DOC>
<DOC>
<DOCNO> 12771 </DOCNO>
Dynamics of fermions coupling to a U(1) gauge field in the limit


  We study in this paper the properties of a gas of fermions coupling to a U(1)
gauge field at wavevectors $q<\Lambda<<k_F$ at dimensions larger than one,
where $\Lambda<<k_F$ is a high momentum cutoff and $k_F$ is the fermi wave
vector. In particular, we shall consider the $e^2\to\infty$ limit where charge
and current fluctuations at wave vectors $q<\Lambda$ are forbidden. Within a
bosonization approximation, effective actions describing the low energy physics
of the system are constructed, where we show that the system can be described
as a fermion liquid formed by chargeless quasi-particles which has vanishing
wavefunction overlap with the bare fermions in the system.

</DOC>
<DOC>
<DOCNO> 10086 </DOCNO>
Interaction induced delocalisation for two particles in a periodic


  We consider two interacting particles evolving in a one-dimensional periodic
structure embedded in a magnetic field. We show that the strong localization
induced by the magnetic field for particular values of the flux per unit cell
is destroyed as soon as the particles interact. We study the spectral and the
dynamical aspects of this transition.

</DOC>
<DOC>
<DOCNO> 40521 </DOCNO>
$B_s$ Mixing at SLD


  We set a preliminary 95% C.L. exclusion on the oscillation frequency of
$B_s^0 - \bar{B_s^0}$ mixing using a sample of 400,000 hadronic $Z^0$ decays
collected by the SLD experiment at the SLC during the 1996-98 run. Three
analyses are presented in this paper. The first analysis partially reconstructs
the $B_s^0$ by combining a fully reconstructed $D_s$ with the remaining charged
B decay tracks. The second analysis selects a sample of events with a partially
reconstructed charm vertex and a lepton track. The third analysis reconstructs
b-hadrons topologically and exploits the $b \to c$ cascade charge structure to
determine the flavor of the b-hadron at decay. All three analyses take
advantage of the large forward-backward asymmetry of the polarized $Z^0 \to b
\bar{b}$ decays and information in the hemisphere opposite to the reconstructed
B vertex to determine the b-hadron flavor at production. The results of the
three analyses are combined to exclude the following values of the $B_s^0 -
\bar{B_s^0}$ oscillation frequency: $\Delta m_s < 7.6 ps^{-1}$ and $11.8 <
\Delta m_s < 14.8 ps^{-1}$ at the 95% confidence level.

</DOC>
<DOC>
<DOCNO> 151194 </DOCNO>
Strings in AdS_3 and the SL(2,R) WZW Model. Part 2: Euclidean Black Hole


  We consider the one-loop partition function for Euclidean BTZ black hole
backgrounds or equivalently thermal AdS_3 backgrounds which are quotients of
H_3 (Euclidean AdS_3). The one-loop partition function is modular invariant and
we can read off the spectrum which is consistent to that found in
hep-th/0001053. We see long strings and discrete states in agreement with the
expectations.

</DOC>
<DOC>
<DOCNO> 40357 </DOCNO>
Kaon and $\Phi$ production vs Participants in Nuclear Collisions


  Data on kaon and $\Phi$ production in nuclear collisions as a function of
centrality are analysed both at AGS and SPS energy range. We compare the
results of several experiments, looking for common trend in `participant
scaling' of production yields. We find a smooth description of scaled kaon and
$\Phi$ yields as a function of participant density. We also show a participant
density dependence of kaons and $\Phi$ produced in the forward hemisphere for
proton-nucleus collisions.

</DOC>
<DOC>
<DOCNO> 11295 </DOCNO>
Surface states in nearly modulated systems


  A Landau model is used to study the phase behavior of the surface layer for
magnetic and cholesteric liquid crystal systems that are at or near a Lifshitz
point marking the boundary between modulated and homogeneous bulk phases. The
model incorporates surface and bulk fields and includes a term in the free
energy proportional to the square of the second derivative of the order
parameter in addition to the usual term involving the square of the first
derivative. In the limit of vanishing bulk field, three distinct types of
surface ordering are possible: a wetting layer, a non-wet layer having a small
deviation from bulk order, and a different non-wet layer with a large deviation
from bulk order which decays non-monotonically as distance from the wall
increases. In particular the large deviation non-wet layer is a feature of
systems at the Lifshitz point and also those having only homogeneous bulk
phases.

</DOC>
<DOC>
<DOCNO> 80935 </DOCNO>
Differential decay rate for $B \to \pi l \nu$ semileptonic decays


  We present our study on $B \to \pi l \nu$ semileptonic decay form factors
with NRQCD action for heavy quark from a quenched lattice QCD simulation at
$\beta$=5.9 on a $16^3\times 48$ lattice. We obtain form factors defined in the
context of heavy quark effective theory by Burdman et al. and find that their
$1/m_B$ correction is small. The limit of physical heavy and light quark masses
can be performed without introducing any model function, and we obtain a
prediction for the differential decay rate $d\Gamma/dq^2$. We also discuss the
soft pion limit of the form factors.

</DOC>
<DOC>
<DOCNO> 84118 </DOCNO>
About the detection of gravitational wave bursts


  Several filtering methods for the detection of gravitational wave bursts in
interferometric detectors are presented. These are simple and fast methods
which can act as online triggers. All methods are compared to matched filtering
with the help of a figure of merit based on the detection of supernovae signals
simulated by Zwerger and Muller.

</DOC>
<DOC>
<DOCNO> 118571 </DOCNO>
QSOs and Absorption Line Systems Surrounding the Hubble Deep Field


  We have imaged a 45x45 sq. arcmin. area centered on the Hubble Deep Field
(HDF) in UBVRI passbands, down to respective limiting magnitudes of
approximately 21.5, 22.5, 22.2, 22.2, and 21.2. The principal goals of the
survey are to identify QSOs and to map structure traced by luminous galaxies
and QSO absorption line systems in a wide volume containing the HDF. We have
selected QSO candidates from color space, and identified 4 QSOs and 2 narrow
emission-line galaxies (NELGs) which have not previously been discovered,
bringing the total number of known QSOs in the area to 19. The bright z=1.305
QSO only 12 arcmin. away from the HDF raises the northern HDF to nearly the
same status as the HDF-S, which was selected to be proximate to a bright QSO.
About half of the QSO candidates remain for spectroscopic verification.
Absorption line spectroscopy has been obtained for 3 bright QSOs in the field,
using the Keck 10m, ARC 3.5m, and MDM 2.4m telescopes. Five heavy-element
absorption line systems have been identified, 4 of which overlap the
well-explored redshift range covered by deep galaxy redshift surveys towards
the HDF. The two absorbers at z=0.5565 and z=0.5621 occur at the same redshift
as the second most populated redshift peak in the galaxy distribution, but each
is more than 7Mpc/h (comoving, Omega_M=1, Omega_L=0) away from the HDF line of
sight in the transverse dimension. This supports more indirect evidence that
the galaxy redshift peaks are contained within large sheet-like structures
which traverse the HDF, and may be precursors to large-scale ``pancake''
structures seen in the present-day galaxy distribution.

</DOC>
<DOC>
<DOCNO> 121260 </DOCNO>
Origin of the scatter in the X-ray luminosity of early-type galaxies


  Statistical properties of X-ray luminosity and temperature are studied for 52
early-type galaxies based on the ROSAT PSPC data. All of the X-ray luminous
galaxies show largely extended emission with a radius of a few times of
10$r_e$, while X-ray faint galaxies do not show such a component. This leads to
a division of early-type galaxies into two categories: X-ray extended and X-ray
compact galaxies. Except for a few galaxies in dense cluster environments, the
luminosity and temperature of X-ray compact galaxies are well explained by a
kinematical heating of the gas supplied by stellar mass loss. In contrast,
X-ray extended galaxies indicate large scatter in the X-ray luminosity. We
discuss that X-ray extended galaxies are the central objects of large potential
structures, and the presence and absence of this potential is the main origin
of the large scatter in the X-ray luminosity.

</DOC>
<DOC>
<DOCNO> 178875 </DOCNO>
Isovector multiphonon excitations in near spherical nuclei


  The lowest isoscalar and isovector quadrupole and octupole excitations in
near spherical nuclei are studied within the the proton-neutron version of the
interacting boson model including quadrupole and octupole bosons (sdf-IBM-2).
The main decay modes of these states in near spherical nuclei are discussed.

</DOC>
<DOC>
<DOCNO> 85639 </DOCNO>
Vacuum Energy


  There appears to be three, perhaps related, ways of approaching the nature of
vacuum energy . The first is to say that it is just the lowest energy state of
a given, usually quantum, system. The second is to equate vacuum energy with
the Casimir energy. The third is to note that an energy difference from a
complete vacuum might have some long range effect, typically this energy
difference is interpreted as the cosmological constant. All three approaches
are reviewed, with an emphasis on recent work. It is hoped that this review is
comprehensive in scope. There is a discussion on whether there is a relation
between vacuum energy and inertia. The solution suggested here to the nature of
the vacuum is that Casimir energy can produce short range effects because of
boundary conditions, but that at long range there is no overall effect of
vacuum energy, unless one considers lagrangians of higher order than Einstein's
as vacuum induced. No original calculations are presented in support of this
position. This is not a review of the cosmological constant {\it per se}, but
rather vacuum energy in general, my approach to the cosmological constant is
not standard.

</DOC>
<DOC>
<DOCNO> 121979 </DOCNO>
Extended [C I] and ^{13}CO(5-4) Emission in M17SW


  We mapped a 13 by 22 pc region in emission from 492 GHz [C I] and, for the
first time, 551 GHz ^{13}CO(5-4) in the giant molecular cloud M17SW, using the
Submillimeter Wave Astronomy Satellite. The morphologies of the [C I] and
^{13}CO emission are strikingly similar. The extent and intensity of the [C I]
and ^{13}CO(5-4) emission is explained as arising from photodissociation
regions on the surfaces of embedded molecular clumps. Modeling of the
^{13}CO(5-4) emission in comparison to ^{13}CO(1-0) indicates a temperature
gradient across the cloud, peaking to at least 63 K near the M17 ionization
front and decreasing to at least 20 K at the western edge of the cloud. We see
no correlation between gas density and column density. The beam-averaged column
density of C I in the core is 1x10^{18} cm^-2, and the mean column density
ratio N(C I)/N(CO) is about 0.4. The variations of N(C I)/N(CO) with position
in M17SW indicate a similar clump size distribution throughout the cloud.

</DOC>
<DOC>
<DOCNO> 85648 </DOCNO>
Are Extremal 2D Black Holes Really Frozen ?


  In the standard methodology for evaluating the Hawking radiation emanating
from a black hole, the background geometry is fixed. Trying to be more
realistic we consider a dynamical geometry for a two-dimensional charged black
hole and we evaluate the Hawking radiation as tunneling process. This
modification to the geometry gives rise to a nonthermal part in the radiation
spectrum. We explore the consequences of this new term for the extremal case.

</DOC>
<DOC>
<DOCNO> 99752 </DOCNO>
Blocking measures for asymmetric exclusion processes via coupling


  We give sufficient conditions on the rates of two asymmetric exclusion
processes such that the existence of a blocking invariant measure for the first
implies the existence of such a measure for the second. The main tool is a
coupling between the two processes under which the first dominates the second
in an appropriate sense. In an appendix we construct a class of processes for
which the existence of a blocking measure can be proven directly; these are
candidates for comparison processes in applications of the main result.

</DOC>
<DOC>
<DOCNO> 69197 </DOCNO>
Renormalization of quark axial current in the chiral potential model


  Non-conserved composite operators like the quark axial current have divergent
matrix elements therefore must be renormalized. We explore how this can be done
in quark model calculations where the systematic procedure of dimensional
regularization and minimal subtraction is not applicable. We propose a most
natural and convenient regularization scheme of cutting the intermediate quark
states over which we sum in loop diagram calculations at a certain energy. We
show that this scheme works perfectly for the quark axial current and we obtain
the quark spin contribution to the proton spin: $\Delta_u=0.82$,
$\Delta_d=-0.43$, $\Delta_s=-0.10$, which is in excellent agreement with
experiments.

</DOC>
<DOC>
<DOCNO> 101037 </DOCNO>
Integral representations and Liouville theorems for solutions of


  The paper contains integral representations for certain classes of
exponentially growing solutions of second order periodic elliptic equations.
These representations are the analogs of those previously obtained by S. Agmon,
S. Helgason, and other authors for solutions of the Helmholtz equation. When
one restricts the class of solutions further, requiring their growth to be
polynomial, one arrives to Liouville type theorems, which describe the
structure and dimension of the spaces of such solutions. The Liouville type
theorems previously proved by M. Avellaneda and F.-H. Lin, and J. Moser and M.
Struwe for periodic second order elliptic equations in divergence form are
significantly extended. Relations of these theorems with the analytic structure
of the Fermi and Bloch surfaces are explained.

</DOC>
<DOC>
<DOCNO> 68134 </DOCNO>
Extracting particle freeze-out phase-space densities and entropies from


  The space-averaged phase-space density and entropy per particle are both
fundamental observables which can be extracted from the two-particle
correlation functions measured in heavy-ion collisions. Two techniques have
been proposed to extract the densities from correlation data: either by using
the radius parameters from Gaussian fits to meson correlations or by using
source imaging, which may be applied to any like pair correlation. We show that
the imaging and Gaussian fits give the same result in the case of meson
interferometry. We discuss the concept of an equivalent instantaneous source on
which both techniques rely. We also discuss the phase-space occupancy and
entropy per particle. Finally, we propose an improved formula for the
phase-space occupancy that has a more controlled dependence on the uncertainty
of the experimentally measured source functions.

</DOC>
<DOC>
<DOCNO> 8690 </DOCNO>
The Effect of the Environment on alpha-Al_2O_3 (0001) Surface Structures


  We report that calculating the Gibbs free energy of the alpha-Al_2O_3 (0001)
surfaces in equilibrium with a realistic environment containing both oxygen and
hydrogen species is essential for obtaining theoretical predictions consistent
with experimental observations. Using density-functional theory we find that
even under conditions of high oxygen partial pressure, the metal terminated
surface is surprisingly stable. An oxygen terminated alpha-Al_2O_3 (0001)
surface becomes stable only if hydrogen is present on the surface. In addition,
including hydrogen on the surface resolves discrepancies between previous
theoretical work and experimental results with respect to the magnitude and
direction of surface relaxations.

</DOC>
<DOC>
<DOCNO> 116523 </DOCNO>
Spatial Gravity


  Hubble's correlation of red-shift with distance reveals that the universe is
expanding, and that spacetime curvature has increased over time. And since time
and space have equal status as dimensions, an object moving through time
experiences increasing spatial curvature due to expansion, just as it does when
moving through space towards a massive body. So expansion must increase
gravity, and this increase would be proportional to the amount of red-shift.
The kinetic energy of expansion is thus exchanged for curvature of spacetime,
and this results in spatial gravity. Momentum therefore fuels both spatial and
massive gravity. And spatial gravity, which must therefore be proportional to
the size of the universe, combines with massive gravity to produce overall
gravity. A cosmological factor proportional to the size of the universe is
therefore appropriate. And the very expansion which causes increasing spatial
gravity, should cause expansion to be self-limiting.

</DOC>
<DOC>
<DOCNO> 120927 </DOCNO>
Kinematics and morphology of the Narrow-Line Region in the Seyfert


  We present a high spatial and spectral resolution 2-D echelle spectrogram of
the Narrow-Line Region in the Seyfert 2 galaxy NGC1386. This Seyfert galaxy was
observed with CASPEC in the wavelength range 5270-7725 Angstrom which covers
the H-alpha and the [N II] lines. With the use of spatially high resolved
images taken with the WFPC2 aboard the Hubble Space Telescope we could identify
individual components of the Narrow-Line Region in our spectra. A Gaussian
decomposition of the spectra revealed 9 distinct emission-line complexes. The
brightest component is blue-shifted by -120+-10 km/s with respect to the
systemic velocity and shows an offset of -1.6" relative to the nucleus of the
galaxy. The true nucleus of NGC1386 has a much lower apparent H-alpha
luminosity than this component. The nucleus is probably highly absorbed.
Although the majority of the Narrow-Line Region components follows a regular
velocity field, we find evidence for a separate kinematic component. The
Narrow-Line Region is aligned anti-parallel to the radio-jet which propagates
from the center of NGC1386 to the south.

</DOC>
<DOC>
<DOCNO> 8594 </DOCNO>
Integrable Chain Model with Additional Staggered Model Parameter


  The generalization of the Yang-Baxter equations (YBE) in the presence of Z_2
grading along both chain and time directions is presented. The XXZ model with
staggered disposition along a chain of both, the anisotropy \pm\Delta, as well
as shifts of the spectral parameters are considered and the corresponding
integrable model is constructed. The Hamiltonian of the model is computed in
fermionic and spin formulations. It involves three neighbour site interactions
and therefore can be considered as a zig-zag ladder model. The Algebraic Bethe
Ansatz technique is applied and the eigenstates, along with eigenvalues of the
transfer matrix of the model are found. The model has a free fermionic limit at
\Delta=0 and the integrable boundary terms are found in this case.
  This construction is quite general and can be applied to other known
integrable models.

</DOC>
<DOC>
<DOCNO> 8574 </DOCNO>
Magnetic pair-breaking in superconducting (Ba,K)BiO_3 investigated by


  The de Gennes and Maki theory of gapless superconductivity for dirty
superconductors is used to interpret the tunneling measurements on the strongly
type-II high-Tc oxide-superconductor Ba1-xKxBiO3 in high magnetic fields up to
30 Tesla. We show that this theory is applicable at all temperatures and in a
wide range of magnetic fields starting from 50 percent of the upper critical
field Bc2. In this magnetic field range the measured superconducting density of
states (DOS) has the simple energy dependence as predicted by de Gennes from
which the temperature dependence of the pair-breaking parameter alpha(T), or
Bc2(T), has been obtained. The deduced temperature dependence of Bc2(T) follows
the Werthamer-Helfand-Hohenberg prediction for classical type-II
superconductors in agreement with our previous direct determination. The
amplitudes of the deviations in the DOS depend on the magnetic field via the
spatially averaged superconducting order parameter which has a square-root
dependence on the magnetic field. Finally, the second Ginzburg-Landau parameter
kappa2(T) has been determined from the experimental data.

</DOC>
<DOC>
<DOCNO> 178897 </DOCNO>
Parity Violating Measurements of Neutron Densities and Nuclear Structure


  Parity violating electron nucleus scattering is a clean and powerful tool for
measuring the spatial distributions of neutrons in nuclei with unprecedented
accuracy. Parity violation arises from the interference of electromagnetic and
weak neutral amplitudes, and the $Z^0$ of the Standard Model couples primarily
to neutrons at low $Q^2$. Experiments are now feasible at existing facilities.
We show that theoretical corrections are either small or well understood, which
makes the interpretation clean. A neutron density measurement may have many
implications for nuclear structure, atomic parity nonconservation experiments,
and the structure of neutron stars.

</DOC>
<DOC>
<DOCNO> 151909 </DOCNO>
Exactly Solvable Quantum Mechanical Models with Infinite Renormalization


  The main difficulty of quantum field theory is the problem of divergences and
renormalization. However, realistic models of quantum field theory are
renormalized within the perturbative framework only. It is important to
investigate renormalization beyond perturbation theory. However, known models
of constructive field theory do not contain such difficulties as infinite
renormalization of the wave function. In this paper an exactly solvable quantum
mechanical model with such a difficulty is constructed. This model is a
simplified analog of the large-N approximation to the $\Phi\phi^a\phi^a$-model
in 6-dimensional space-time. It is necessary to introduce an indefinite inner
product to renormalize the theory. The mathematical results of the theory of
Pontriagin spaces are essentially used. It is remarkable that not only the
field but also the canonically conjugated momentum become well-defined
operators after adding counterterms.

</DOC>
<DOC>
<DOCNO> 14118 </DOCNO>
Operator-Algebraic Approach to the Yrast Spectrum of Weakly Interacting


  We present an operator-algebraic approach to deriving the low-lying
quasi-degenerate spectrum of weakly interacting trapped N bosons with total
angular momentum \hbar L for the case of small L/N, demonstrating that the
lowest-lying excitation spectrum is given by 27 g n_3(n_3-1)/34, where g is the
strength of the repulsive contact interaction and n_3 the number of excited
octupole quanta. Our method provides constraints for these quasi-degenerate
many-body states and gives higher excitation energies that depend linearly on
N.

</DOC>
<DOC>
<DOCNO> 68257 </DOCNO>
Linearized Gravity in Brane Backgrounds


  A treatment of linearized gravity is given in the Randall-Sundrum background.
The graviton propagator is found in terms of the scalar propagator, for which
an explicit integral expression is provided. This reduces to the
four-dimensional propagator at long distances along the brane, and provides
estimates of subleading corrections. Asymptotics of the propagator off the
brane yields exponential falloff of gravitational fields due to matter on the
brane. This implies that black holes bound to the brane have a "pancake"-like
shape in the extra dimension, and indicates validity of a perturbative
treatment off the brane. Some connections with the AdS/CFT correspondence are
described.

</DOC>
<DOC>
<DOCNO> 150889 </DOCNO>
Non-Abelian Aharonov-Bohm Scattering of Spin 1/2 Particles


  We study the low energy regime of the scattering of two fermionic particles
carrying isospin 1/2 and interacting through a non-Abelian Chern-Simons field.
We calculate the one-loop scattering amplitude for both the nonrelativistic and
also for the relativistic theory. In the relativistic case we introduce an
intermediate cutoff, separating the regions with low and high loop momenta
integration. In this procedure purely relativistic field theory effects as the
vacuum polarization and anomalous magnetic moment corrections are automatically
incorporated.

</DOC>
<DOC>
<DOCNO> 169890 </DOCNO>
Geometric Algebra in Quantum Information Processing


  This paper develops a geometric model for coupled two-state quantum systems
(qubits), which is formulated using geometric (aka Clifford) algebra. It begins
by showing how Euclidean spinors can be interpreted as entities in the
geometric algebra of a Euclidean vector space. This algebra is then lifted to
Minkowski space-time and its associated geometric algebra, and the insights
this provides into how density operators and entanglement behave under Lorentz
transformations are discussed. The direct sum of multiple copies of space-time
induces a tensor product structure on the associated algebra, in which a
suitable quotient is isomorphic to the matrix algebra conventionally used in
multi-qubit quantum mechanics. Finally, the utility of geometric algebra in
understanding both unitary and nonunitary quantum operations is demonstrated on
several examples of interest in quantum information processing.

</DOC>
<DOC>
<DOCNO> 116972 </DOCNO>
Development of Superconducting Linac for the Kek/Jaeri Joint Project


  The JAERI/KEK Joint Project for the high-intensity proton accelerator
facility has been proposed with a superconducting (SC) linac option from 400
MeV to 600MeV. System design of the SC linac has been carried out based on the
equipartitioning concept. The SC linac is planned to use as an injector to a
3GeV rapid cycling synchrotron (RCS) for spallation neutron source after it
meets requirement to momentum spread less than +-0.1%. In the R&D work for SC
cavities, vertical tests of single-cell and 5 cell cavities were performed.
Experiments on multi-cell (5 cell) cavities of b=0.50 and b=0.89 at 2K were
carried out with values of maximum electric surface peak fields of 23MV/m and
31MV/m, respectively. A model describing dynamic Lorentz detuning for SC
cavities has been developed for pulse mode operation. Validity of the model was
confirmed experimentally to simulate the performance.

</DOC>
<DOC>
<DOCNO> 68904 </DOCNO>
On the low-energy limit of string and M-theory


  We discuss the possible applications of string theory for the construction of
generalizations of the $SU(3)\times SU(2)\times U(1)$ standard model of strong
and electroweak interactions. This includes an investigation of effective $d=4$
dimensional supergravity theories that could be derived from higher dimensional
string theories ($d=10$) and M-theory ($d=11$).It is shown how the question of
unification of gauge and gravitational coupling constants could find a solution
within this framework. The mechanism of hidden sector supersymmetry breakdown
and its consequences for the pattern for soft supersymmetry breaking terms are
discussed in detail.

</DOC>
<DOC>
<DOCNO> 10988 </DOCNO>
A Monte Carlo Method for Fermion Systems Coupled with Classical Degrees


  A new Monte Carlo method is proposed for fermion systems interacting with
classical degrees of freedom. To obtain a weight for each Monte Carlo sample
with a fixed configuration of classical variables, the moment expansion of the
density of states by Chebyshev polynomials is applied instead of the direct
diagonalization of the fermion Hamiltonian. This reduces a cpu time to scale as
$O(N_{\rm dim}^{2} \log N_{\rm dim})$ compared to $O(N_{\rm dim}^{3})$ for the
diagonalization in the conventional technique; $N_{\rm dim}$ is the dimension
of the Hamiltonian. Another advantage of this method is that parallel
computation with high efficiency is possible. These significantly save total
cpu times of Monte Carlo calculations because the calculation of a Monte Carlo
weight is the bottleneck part. The method is applied to the double-exchange
model as an example. The benchmark results show that it is possible to make a
systematic investigation using a system-size scaling even in three dimensions
within a realistic cpu timescale.

</DOC>
<DOC>
<DOCNO> 101753 </DOCNO>
Interfaces and droplets in quantum lattice models


  This paper is a short review of recent results on interface states in the
Falicov-Kimball model and the ferromagnetic XXZ Heisenberg model. More
specifically, we discuss the following topics: 1) The existence of interfaces
in quantum lattice models that can be considered as perturbations of classical
models. 2) The rigidity of the 111 interface in the three-dimensional
Falicov-Kimball model at sufficiently low temperatures. 3) The low-lying
excitations and the scaling of the gap in the 111 interface ground state in the
ferromagnetic XXZ Heisenberg model in three dimensions. 4) The existence of
droplet states in the XXZ chain and their properties.

</DOC>
<DOC>
<DOCNO> 102724 </DOCNO>
Instantons on the Quantum 4-Spheres S^4_q


  We introduce noncommutative algebras $A_q$ of quantum 4-spheres $S^4_q$, with
$q\in\IR$, defined via a suspension of the quantum group $SU_q(2)$, and a
quantum instanton bundle described by a selfadjoint idempotent $e\in
\Mat_4(A_q)$, $e^2=e=e^*$. Contrary to what happens for the classical case or
for the noncommutative instanton constructed in Connes-Landi, the first
Chern-Connes class $ch_1(e)$ does not vanish thus signaling a dimension drop.
The second Chern-Connes class $ch_2(e)$ does not vanish as well and the couple
$(ch_1(e), ch_2(e))$ defines a cycle in the $(b,B)$ bicomplex of cyclic
homology.

</DOC>
<DOC>
<DOCNO> 122887 </DOCNO>
The Cosmological Evolution of BL Lacertae Objects


  We review the main results from several radio, X-ray and multi-frequency
surveys on the topic of cosmological evolution of BL Lacertae objects. Updated
findings on BL Lac evolution following the recent identification of many
sources in the ``Sedentary Multi-Frequency survey'' are also discussed. By
means of extensive Monte Carlo simulations we test some possible explanations
for the peculiar cosmological evolution of BL Lacs. We find that a dependence
of the relativistic Doppler factor on radio luminosity (as expected within the
beaming scenario) may induce low values of V/V_max and that both edge effects
at the low luminosity end of the BL Lacs radio luminosity function, and
incompleteness at faint optical magnitudes may be the cause of the low V/V_max
found for extreme HBL sources in X-ray selected samples.

</DOC>
<DOC>
<DOCNO> 71005 </DOCNO>
Nuclear effects and higher twists in F3 structure function


  We analyze the CCFR collaboration iron target data on the xF3 structure
function making particular emphasis on the extraction of the higher twist
contributions from data. Corrections for nuclear effects are applied in order
to extract data on the structure function of the isoscalar nucleon. Our
analysis confirms the observation made earlier, that the higher twist terms
depend strongly on the level to which QCD perturbation theory analysis is
applied. We discuss the impact of nuclear effects on the higher twist term as
well as on the QCD scale parameter Lambda_{\bar{MS}} extracted from the fit to
data.

</DOC>
<DOC>
<DOCNO> 117018 </DOCNO>
Purine-pyrimidine symmetry, determinative degree and DNA


  Various symmetries connected with purine-pyrimidine content of DNA sequences
are studied in terms of the intruduced determinative degree, a new
characteristics of nucleotide which is connected with codon usage. A
numerological explanation of CG pressure is proposed. A classification of DNA
sequences is given. Calculations with real sequences show that
purine-pyrimidine symmetry increases with growing of organization. A new small
parameter which characterizes the purine-pyrimidine symmetry breaking is
proposed for the DNA theory.

</DOC>
<DOC>
<DOCNO> 122122 </DOCNO>
Tidal streams in the Galactic halo: Evidence for the Sagittarius


  Standard cosmology predicts that dwarfs were the first galaxies to be formed
in the Universe and that many of them merge afterwards to form bigger galaxies
such as the Milky Way. This process would have left behind traces such as tidal
debris or star streams in the outer halo. We report here the detection of a
very low density stellar system at 50+/- 10 kpc from the Galactic center that
could be related to the merger process. It could form part of the Sagittarius
northern stream or, alternatively, could be the trace of a hitherto unknown
dwarf galaxy.
  The dwarf galaxy in Sagittarius, the closest satellite of the Milky Way, is
currently being tidally disrupted and is a ``living'' test for galaxy formation
theories. The system found here is 60 deg away from the center of the
Sagittarius galaxy. If it is really associated with this galaxy, it would
confirm predictions of dynamical interaction models indicating that tidal
debris from Sagittarius could extend along a stream completely enveloping the
Milky Way in a polar orbit.

</DOC>
<DOC>
<DOCNO> 151773 </DOCNO>
Hidden Supersymmetry


  Inspired by the concept of complementarity, we present a illustrative model
for the weak interactions with unbroken gauge symmetry and unbroken
supersymmetry. The observable particles are bound states of some more
fundamental particles. Supersymmetry is broken at the macroscopic scale of the
observable particles by a discrete symmetry but remains exact at the scale of
the fundamental particle and is thus hidden. This provides a link between
theories at very high energies and the observed particle physics.
Supersymmetric particles are confined in usual matter.

</DOC>
<DOC>
<DOCNO> 178499 </DOCNO>
Fluctuation of Voids in Hadronization at Phase Transition


  Starting from the recognition that hadrons are not produced smoothly at phase
transition, the fluctuation of spatial patterns is investigated by finding a
measure of the voids that exhibits scaling behavior. The Ising model is used to
simulate a cross-over in quark-hadron phase transition. A threshold in hadron
density is used to define a void. The dependence of the scaling exponents on
that threshold is found to provide useful information on some properties of the
hadronization process. The complication in heavy-ion collision introduces the
possibility of configuration mixing, which can also be studied in this
approach. Numerical criteria on the scaling exponents have been found that can
be used to discriminate phase-transition processes from other hadronization
processes having nothing to do with critical phenomena.

</DOC>
<DOC>
<DOCNO> 170691 </DOCNO>
Berry's phase for compact Lie groups


  The Lie group adiabatic evolution determined by a Lie algebra parameter
dependent Hamiltonian is considered. It is demonstrated that in the case when
the parameter space of the Hamiltonian is a homogeneous K\"ahler manifold its
fundamental K\"ahler potentials completely determine Berry geometrical phase
factor. Explicit expressions for Berry vector potentials (Berry connections)
and Berry curvatures are obtained using the complex parametrization of the
Hamiltonian parameter space. A general approach is exemplified by the Lie
algebra Hamiltonians corresponding to SU(2) and SU(3) evolution groups.

</DOC>
<DOC>
<DOCNO> 118099 </DOCNO>
Integrable models of galactic discs with double nuclei


  We introduce a new class of 2-D mass models, whose potentials are of
St\"ackel form in elliptic coordinates. Our model galaxies have two separate
strong cusps that form double nuclei. The potential and surface density
distributions are locally axisymmetric near the nuclei and become {\it highly}
non-axisymmetric outside the nucleus. The surface density diverges toward the
cuspy nuclei with the law $\Sigma \propto r^{-2}$. Our model is sustained by
four general types of regular orbits: {\it butterfly}, {\it nucleuphilic
banana}, {\it horseshoe} and {\it aligned loop} orbits. Horseshoes and
nucleuphilic bananas support the existence of cuspy regions. Butterflies and
aligned loops control the non-axisymmetric shape of outer regions. Without any
need for central black holes, our distributed mass models resemble the nuclei
of M31 and NGC4486B. It is also shown that the self-gravity of the stellar disc
can prevent the double nucleus to collapse.

</DOC>
<DOC>
<DOCNO> 68809 </DOCNO>
Abelian dominance in low-energy Gluodynamics due to dynamical mass


  We show that off-diagonal gluons and off-diagonal ghosts acquire their masses
dynamically in QCD if the maximal Abelian gauge is adopted. This result
strongly supports the Abelian dominance in low-energy region of QCD. The mass
generation is shown to occur due to ghost-anti-ghost condensation caused by
attractive quartic ghost interactions within the Abelian projected effective
gauge theory (derived by one of the authors). In fact, the quartic ghost
interaction is indispensable for the renormalizability due to nonlinearity of
the maximal Abelian gauge. The ghost-anti-ghost condensation is associated with
the spontaneous breaking of global SL(2,R) symmetry recently found by Schaden
at least for SU(2) case. Moreover we write down a new extended BRS algebra in
the maximal Abelian gauge which should be compared with that of Nakanishi-Ojima
for the Lorentz gauge. Finally, we argue that the mass generation may be
related to the spontaneous breaking of a supersymmetry $OSp(4|2)$ hidden in the
maximal Abelian gauge.

</DOC>
<DOC>
<DOCNO> 118664 </DOCNO>
Physical conditions in broad and associated narrow absorption-line


  Results of a careful analysis of the absorption systems with zabs = zem seen
toward the bright, z_em ~ 3.91, gravitationally lensed quasar APM 08279+5255
are presented. Two of the narrow-line systems, at z_abs = 3.8931 and z_abs =
3.9135, show absorptions from singly ionized species with weak or no NV and O V
absorptions at the same redshift. Absorption due to fine structure transitions
of C II and Si II (excitation energies corresponding to, respectively,
156$\mu$m and 34$\mu$m) are detected at z_abs = 3.8931. Excitation by IR
radiation is favored as the column density ratios are consistent with the shape
of APM 08279+5255 IR spectrum. The low-ionization state of the system favors a
picture where the cloud is closer to the IR source than to the UV source,
supporting the idea that the extension of the IR source is larger than ~ 200
pc. The absence of fine structure lines at z_abs = 3.9135 suggests that the gas
responsible for this system is farther away from the IR source. Abundances are
~ 0.01 and 1$Z_{\odot}$ at z_abs = 3.913 and 3.8931 and aluminum could be
over-abundant with respect to silicon and carbon by at least a factor of two
and five. All this suggests that whereas the \zabs = 3.8931 system is probably
located within 200 pc from the QSO and ejected at a velocity larger than 1000
kms^{-1}, the \zabs = 3.9135 system is farther away and part of the
host-galaxy. (abridged)

</DOC>
<DOC>
<DOCNO> 85627 </DOCNO>
Quantization of Generally Covariant Systems


  Finite dimensional models that mimic the constraint structure of Einstein's
General Relativity are quantized in the framework of BRST and Dirac's canonical
formalisms. The first system to be studied is one featuring a constraint
quadratic in the momenta (the "super-Hamiltonian") and a set of constraints
linear in the momenta (the "supermomentum" constraints). The starting point is
to realize that the ghost contributions to the supermomentum constraint
operators can be read in terms of the natural volume induced by the constraints
in the orbits. This volume plays a fundamental role in the construction of the
quadratic sector of the nilpotent BRST charge. It is shown that the quantum
theory is invariant under scaling of the super-Hamiltonian. As long as the
system has an intrinsic time, this property translates in a contribution of the
potential to the kinetic term. In this aspect, the results substantially differ
from other works where the scaling invariance is forced by introducing a
coupling to the curvature. The contribution of the potential, far from being
unnatural, is beautifully justified in the light of the Jacobi's principle.
Then, it is shown that the obtained results can be extended to systems with
extrinsic time. In this case, if the metric has a conformal temporal Killing
vector and the potential exhibits a suitable behavior with respect to it, the
role played by the potential in the case of intrinsic time is now played by the
norm of the Killing vector. Finally, the results for the previous cases are
extended to a system featuring two super-Hamiltonian constraints. This step is
extremely important due to the fact that General Relativity features an
infinite number of such constraints satisfying a non trivial algebra among
themselves.

</DOC>
<DOC>
<DOCNO> 84808 </DOCNO>
Ill-posedness in the Einstein equations


  It is shown that the formulation of the Einstein equations widely in use in
numerical relativity, namely, the standard ADM form, as well as some of its
variations (including the most recent conformally-decomposed version), suffers
from a certain but standard type of ill-posedness. Specifically, the norm of
the solution is not bounded by the norm of the initial data irrespective of the
data. A long-running numerical experiment is performed as well, showing that
the type of ill-posedness observed may not be serious in specific practical
applications, as is known from many numerical simulations.

</DOC>
<DOC>
<DOCNO> 13286 </DOCNO>
Extended covariance under nonlinear canonical transformation in Weyl


  A theory of nonunitary-invertible as well as unitary canonical
transformations is formulated in the context of Weyl's phase space
representations. Exact solutions of the transformation kernels and the phase
space propagators are given for the three fundamental canonical maps as
fractional-linear, gauge and contact (point) transformations. Under the
nonlinear maps a phase space representation is mapped to another phase space
representation thereby extending the standard concept of covariance. This
extended covariance allows Dirac-Jordan transformation theory to naturally
emerge from the Hilbert space representations in the Weyl quantization.

</DOC>
<DOC>
<DOCNO> 13463 </DOCNO>
Chaotic motion of space charge wavefronts in semiconductors under


  A standard drift-diffusion model of space charge wave propagation in
semiconductors has been studied numerically and analytically under dc voltage
bias. For sufficiently long samples, appropriate contact resistivity and
applied voltage - such that the sample is biased in a regime of negative
differential resistance - we find chaos in the propagation of nonlinear fronts
(charge monopoles of alternating sign) of electric field. The chaos is always
low-dimensional, but has a complex spatial structure; this behavior can be
interpreted using a finite dimensional asymptotic model in which the front
(charge monopole) positions and the electrical current are the only dynamical
variables.

</DOC>
<DOC>
<DOCNO> 8291 </DOCNO>
The excess wing in the dielectric loss of glass-forming ethanol: A


  A detailed dielectric investigation of liquid, supercooled liquid, and glassy
ethanol reveals a third relaxation process, in addition to the two processes
already known. The relaxation time of the newly detected process exhibits
strong deviations from thermally activated behavior. Most important, this
process is the cause of the apparent excess wing, which was claimed to be
present in the dielectric loss spectra of glass-forming ethanol. In addition,
marked deviations of the spectra of ethanol from the scaling proposed by Dixon
and Nagel have been detected.

</DOC>
<DOC>
<DOCNO> 178759 </DOCNO>
An Analytic Solution of Hydrodynamic Equations with Source Terms in


  The energy and baryon densities in heavy ion collisions are estimated by
analytically solving a 1+1 dimensional hydrodynamical model with source terms.
Particularly, a competition between the energy and baryon sources and the
expansion of the system is discussed in detail.

</DOC>
<DOC>
<DOCNO> 121813 </DOCNO>
Quiescent times in gamma-ray bursts: II. Dormant periods in the central


  Within the framework of the internal-external shocks model for gamma-ray
bursts, we study the various mechanisms that can give rise to quiescent times
in the observed gamma-ray light-curves. In particular, we look for the
signatures that can provide us with evidence as to whether or not the central
engine goes dormant for a period of time comparable to the duration of the
gaps. We show that the properties of the prompt gamma-ray and X-ray emission
can in principle determine whether the quiescent episodes are due to a
modulated relativistic wind or a switching off of the central engine. We
suggest that detailed observations of the prompt afterglow emission from the
reverse shock will strongly constrain the possible mechanisms for the
production of quiescent times in gamma-ray bursts.

</DOC>
<DOC>
<DOCNO> 100019 </DOCNO>
A Partition Theorem


  We prove the following: there is a primitive recursive function f_-^*(-,-),
in the three variables, such that: for every natural numbers t,n>0, and c, for
any natural number k>=f^*_t(n,c) the following holds. Assume L is an alphabet
with n>0 letters, M is the family of non empty subsets of {1,...,k} with =<t
members and V is the set of functions from M to L, and lastly d is a
c-colouring of V (i.e. a function with domain V and range with at most c
members). Then there is a d-monochromatic V-line, which means that there are w
included in {1,...,k}, with at least t members and a function r from {u in M: u
not a subset of w} to L such that letting Y={eta in V: eta extends r and for
each s=1,...,t it is constant on {u in M: u is an s-element subset of w}}, we
have: the restriction of d to Y is constant (for t=1 those are the Hales Jewett
numbers).

</DOC>
<DOC>
<DOCNO> 119641 </DOCNO>
A Dynamical Study of Galaxies in the Hickson Compact Groups


  In order to investigate dynamical properties of spiral galaxies in the
Hickson compact groups (HCGs), we present rotation curves of 30 galaxies in 20
HCGs. We found as follows. 1) There is not significant relation between
dynamical peculiarity and morphological peculiarity in HCG spirals. 2) There is
no significant relation between the dynamical properties and the frequency
distribution of nuclear activities in HCG spirals. 3) There are no significant
correlations between the dynamical properties of HCG spirals and any group
properties (i.e., the size, the velocity dispersion, the galaxy number density,
and the crossing time). 4) Asymmetric and peculiar rotation curves are more
frequently seen in the HCG spirals than in field spirals and in cluster ones.
However, this tendency is more obviously seen in late-type HCG spirals. These
results suggest that the dynamical properties of HCG spirals do not strongly
correlate with the morphology, the nuclear activity, and the group properties.
Our results also suggest that more frequent galaxy collisions occur in the HCGs
than in the field and in the clusters.

</DOC>
<DOC>
<DOCNO> 13284 </DOCNO>
What can Physics learn from Continuum Mechanics ?


  This paper is mostly a collection of ideas already published by various
authors, some of them even a long time ago. Its intention is to bring the
reader to know some rather unknown papers of different fields that merit
interest and to show some relations between them the author claims to have
observed. In the first section, some comments on old unresolved problems in
theoretical physics are collected. In the following, I shall explain what
relation exists between Feynman graphs and the teleparallel theory of Einstein
and Cartan in the late 1920s, and the relation of both to the theories of the
incompressible aether around 1840. Reviewing these developments, we will have a
look at the continuum theory of dislocations developed by Kroener in the 1950s
and some techniques of differential geometry and topology relevant for a modern
description of defects in continous media. I will then illustrate some basic
concepts of nonlinear continuum mechanics and discuss applications to the above
theories. By doing so, I hope to attract attention to the possible relevance of
these facts for `fundamental' physics.

</DOC>
<DOC>
<DOCNO> 117901 </DOCNO>
Distance-Redshift in Inhomogeneous FLRW


  We give distance--redshift relations in terms of elliptic integrals for three
different mass distributions of the Friedmann-Lema\^\i tre-Robertson-Walker
(FLRW) cosmology. These models are dynamically pressure free FLRW on large
scales but, due to mass inhomogeneities, differ in their optical properties.
They are the filled-beam model (standard FLRW), the empty-beam model (no mass
density exists in the observing beams) and the 2/3 filled-beam model. For
special $\OM$-- $\OL$ values the elliptic integrals reduce to more familiar
functions. These new expressions for distance-redshift significantly reduce
computer evaluation times.

</DOC>
<DOC>
<DOCNO> 11812 </DOCNO>
Spectroscopic evidence for unconventional superconductivity in


  Reply to cond-mat/0007006 by Gloos

</DOC>
<DOC>
<DOCNO> 80911 </DOCNO>
Sinle-valued and spinor representations of orientation-preserved


  We calculate the single-valued and spinor representations of $SO_4$, the
orientation-preserved subgroup of $O_4$, on the base of our previous work on
four-dimensional cubic group $O_4$.

</DOC>
<DOC>
<DOCNO> 117607 </DOCNO>
Solar cycle variations of large scale flows in the Sun


  Using data from the Michelson Doppler Imager (MDI) instrument on board the
Solar and Heliospheric Observatory (SOHO), we study the large-scale velocity
fields in the outer part of the solar convection zone using the ring diagram
technique. We use observations from four different times to study possible
temporal variations in flow velocity. We find definite changes in both the
zonal and meridional components of the flows. The amplitude of the zonal flow
appears to increase with solar activity and the flow pattern also shifts
towards lower latitude with time.

</DOC>
<DOC>
<DOCNO> 84521 </DOCNO>
Is our vacuum stable?


  The stability of our vacuum is analyzed and several aspects concerning this
question are reviewed. 1) In the standard Glashow-Weinberg-Salam (GWS) model we
review the instability towards the formation of a bubble of lower energy
density and how the rate of such bubble formation process compares with the age
of the Universe for the known values of the GWS model. 2) We also review the
recent work by one of us (E.I.G) concerning the vacuum instability question in
the context of a model that solves the cosmological constant problem. It turns
out that in such model the same physics that solves the cosmological constant
problem makes the vacuum stable. 3) We review our recent work concerning the
instability of elementary particle embedded in our vacuum, towards the
formation of an infinite Universe. Such process is not catastrophic. It leads
to a "bifurcation type" instability in which our Universe is not eaten by a
bubble (instead a baby universe is born). This universe does not replace our
Universe rather it disconnects from it (via a wormhole) after formation.

</DOC>
<DOC>
<DOCNO> 85331 </DOCNO>
Time, what is it? Dynamical Properties of Time


  The phenomenon of local dynamical inhomogeneity of time is predicted, which
implies that the course of time along the trajectory of motion of a particle in
the inertial reference frames moving relative to each other depends on the
state of motion of the particle under the influence of a force field. As is
seen from the results obtained, the ability to influence the course of time
represents one of the most fundamental properties of any material system
intrinsically inherent in it by the very nature of things, which manifests
itself when the system interacts with force fields. The inferences of the paper
are not based on the use of any hypotheses and strictly follow from
relativistic equations of motion. The dependence of the course of time upon the
behaviour of physical system is, thus, a direct consequence of causality
principle, relativity principle and the pseudoeuclidity of space-time. The
results obtained confirm the Kozyrev hypothesis that time has physical
properties and open up radically new opportunities for the efficient control of
physical processes. It is demonstrated with point particle that the change in
the course of time results in the appearance of an additional force acting on
the particle. A general conclusion is drawn on the basis of the theory advanced
that relativistic equations of motion for any kind of matter contain
information about the physical properties of time, which are, thus, of
dynamical nature.

</DOC>
<DOC>
<DOCNO> 121422 </DOCNO>
A nearly symmetric double-image gravitational lens


  We report the discovery of a new double-image gravitational lens resulting
from our search for lenses in the southern sky. Radio source PMN J2004-1349 is
composed of two compact components separated by 1.13 arcseconds in VLA, MERLIN
and VLBA images. The components have a flux ratio of 1:1 at radio frequencies
ranging from 5 GHz to 22 GHz. The I-band optical counterpart is also an equal
double, with roughly the same separation and position angle as the radio
double. Upon subtraction of the components from the I-band image, we identify a
dim pattern of residuals as the lens galaxy. While the present observations are
sufficient to establish that J2004-1349 is a gravitational lens, additional
information will be necessary (such as the redshifts of the galaxy and quasar,
and precise astrometry and photometry of the lens galaxy) before constructing
detailed mass models.

</DOC>
<DOC>
<DOCNO> 69461 </DOCNO>
The high-precision, charge-dependent Bonn nucleon-nucleon potential


  We present a charge-dependent nucleon-nucleon (NN) potential that fits the
world proton-proton data below 350 MeV available in the year of 2000 with a
chi^2 per datum of 1.01 for 2932 data and the corresponding neutron-proton data
with chi^2/datum = 1.02 for 3058 data. This reproduction of the NN data is more
accurate than by any phase-shift analysis and any other NN potential. The
charge-dependence of the present potential (that has been dubbed `CD-Bonn') is
based upon the predictions by the Bonn Full Model for charge-symmetry and
charge-independence breaking in all partial waves with J <= 4. The potential is
represented in terms of the covariant Feynman amplitudes for one-boson exchange
which are nonlocal. Therefore, the off-shell behavior of the CD-Bonn potential
differs in a characteristic and well-founded way from commonly used local
potentials and leads to larger binding energies in nuclear few- and many-body
systems, where underbinding is a persistent problem.

</DOC>
<DOC>
<DOCNO> 69538 </DOCNO>
Pomeron models and exchange degeneracy of the Regge trajectories


  Two models for the Pomeron, supplemented by exchange degenerate sub-leading
Regge trajectories, are fitted to the forward scattering data for a number of
reactions. By considering new Pomeron models, we extend the recent results of
the COMPAS group, being consistent with our predecessors.

</DOC>
<DOC>
<DOCNO> 151518 </DOCNO>
(F1, D1, D3) Bound State, Its Scaling Limits and SL(2,Z) Duality


  We discuss the properties of the bound state (F1, D1, D3) in IIB supergravity
in three different scaling limits and the $SL(2,{\bf Z})$ transformation of the
resulting theories. In the simple decoupling limit with finite electric and
magnetic components of NS $B$ field, the worldvolume theory is the ${\cal N}$=4
super Yang-Mills (SYM) and the supergravity dual is still the $AdS_5 \times
S^5$. In the large magnetic field limit with finite electric field, the theory
is the noncommutative super Yang-Mills (NCSYM), and the supergravity dual is
the same as that without the electric background. We show how to take the
decoupling limit of the closed string for the critical electric background and
finite magnetic field, and that the resulting theory is the noncommutative open
string (NCOS) with both space-time and space-space noncommutativities. It is
shown that under the $SL(2, {\bf Z})$ transformation, the SYM becomes itself
with a different coupling constant, the NCSYM is mapped to a NCOS, and the NCOS
in general transforms into another NCOS and reduces to a NCSYM in a special
case.

</DOC>
<DOC>
<DOCNO> 122354 </DOCNO>
A high-resolution multi-wavelength study of the jet in 3C 273


  We present HST images at 622 nm and 300 nm of the optical jet in 3C273 and
determine the run of the optical spectral index at 0.2" along the jet. We find
no evidence for localized acceleration or loss sites, and support for a
little-changing spectral shape throughout the jet. We consider this further
evidence in favour of a distributed acceleration process.

</DOC>
<DOC>
<DOCNO> 80602 </DOCNO>
Calibration of Smearing and Cooling Algorithms in SU(3)-Color Gauge


  The action and topological charge are used to determine the relative rates of
standard cooling and smearing algorithms in pure SU(3)-color gauge theory. We
consider representative gauge field configurations on $16^3\times 32$ lattices
at $\beta=5.70$ and $24^3\times 36$ lattices at $\beta=6.00$. We find the
relative rate of variation in the action and topological charge under various
algorithms may be succinctly described in terms of simple formulae. The results
are in accord with recent suggestions from fat-link perturbation theory.

</DOC>
<DOC>
<DOCNO> 100429 </DOCNO>
Logarithmic deformations of normal crossing Enriques surfaces in


  Working in characteristic two, I classify nonsmooth Enriques surfaces with
normal crossing singularities. Using Kato's theory of logarithmic structures, I
show that such surfaces are smoothable and lift to characteristic zero,
provided they are d-semistable.

</DOC>
<DOC>
<DOCNO> 151527 </DOCNO>
Trace anomaly and Casimir effect


  The Casimir energy for scalar field of two parallel conductor in two
dimensional domain wall background, with Dirichlet boundary conditions, is
calculated by making use of general properties of renormalized stress tensor.We
show that vacuum expectation values of stress tensor contain two terms which
come from the boundary conditions and the gravitational background. In two
dimensions the minimal coupling reduces to the conformal coupling and stress
tensor can be obtained by the local and non-local contribution of the anomalous
trace. This work shows that there exists a subtle relation between Casimir
effect and trace anomaly in curved space time.

</DOC>
<DOC>
<DOCNO> 116969 </DOCNO>
2D Simulation of High-Efficiency Cross-Field RF Power Sources


  An efficient method for frequency domain analysis of 2D cross-field devices
is presented. This work was done to analyze and design high efficiency
magnetrons. Arbitrary device-geometries are described by a piecewise planar
boundary. The method is based on an expansion of the electromagnetic fields
into a set of cavity eigenmodes. In order to obtain the self-consistent
solution, iterations are performed until the energy balance is reached. A
boundary integration method is used to take into account space charge effects.
The cavity eigenmodes are found by a method based on the scattering matrix
technique. The geometry is divided into regions. The boundary contour
mode-matching method is used to obtain the scattering matrices for each region.
Electromagnetic fields in each region are expanded into a series of plane
waves. Due to choice of plane wave expansion, all integration in the
mode-matching process is carried out analytically. The scattering matrices of
the regions are combined using a generalized scattering matrix technique to
obtain the scattering matrix for the full geometry, and then the eigenmode
resonance frequencies and the fields. Periodic boundary condition is used for
the field calculation and the particle tracking.

</DOC>
<DOC>
<DOCNO> 68677 </DOCNO>
Helicity Amplitudes for Single-Top Production


  Single top quark production at hadron colliders allows a direct measurement
of the top quark charged current coupling. We present the complete tree-level
helicity amplitudes for four processes involving the production and
semileptonic decay of a single top quark: W-gluon fusion, flavor excitation,
s-channel production and W-associated production. For the first three processes
we study the quality of the narrow top width approximation. We also examine
momentum and angular distributions of some of the final state particles.

</DOC>
<DOC>
<DOCNO> 71231 </DOCNO>
Top quark production at future lepton colliders in the asymptotic regime


  The production of a tt(bar) pair from lepton-antilepton annihilation is
considered for values of the center of mass energy much larger than the top
mass, typically of the few TeV size. In this regime a number of simplifications
occurs that allows to derive the leading asymptotic terms of various
observables using the same theoretical description that was used for light
quark production. Explicit examples are shown for the Standard Model and the
Minimal Supersymmetric Standard Model cases.

</DOC>
<DOC>
<DOCNO> 179053 </DOCNO>
Multi-gap superfluidity in nuclear matter


  It is shown that under lowering density or temperature a nucleon Fermi
superfluid can undergo a phase transition to a new superfluid state
corresponding to superposition of states with singlet-triplet (ST) and
triplet-singlet (TS) pairing of nucleons (in spin and isospin spaces). Such
states arise as a result of branching from one-gap solution of the
self-consistent equations, describing ST pairing of nucleons. The density and
temperature dependence of the order parameters for new two-gap solutions is
determined in the model with Skyrme effective forces.

</DOC>
<DOC>
<DOCNO> 178765 </DOCNO>
Effective hadronic Lagrangian for charm mesons


  An effective hadronic Lagrangian including the charm mesons is introduced to
study their interactions in hadronic matter. Using coupling constants that are
determined either empirically or by the SU(4) symmetry, we have evaluated the
absorption cross sections of $J/\psi$ and the scattering cross sections of $D$
and $D^*$ by $\pi$ and $\rho$ mesons.

</DOC>
<DOC>
<DOCNO> 122458 </DOCNO>
Chandra detection of reflected X-ray emission from the type 2 QSO in


  We present X-ray imaging spectroscopy of the extremely luminous infrared
galaxy IRAS 09104+4109 (z=0.442) obtained with the Chandra X-ray Observatory.
With the arcsec resolution of Chandra, an unresolved source at the nucleus is
separated from the surrounding cluster emission. A strong iron K line at 6.4
keV on a very hard continuum is detected from the nuclear source, rendering
IRAS 09104+4109 the most distant reflection-dominated X-ray source known.
Combined with the BeppoSAX detection of the excess hard X-ray emission, it
provides further strong support to the presence of a hidden X-ray source of
quasar luminosity in this infrared galaxy. Also seen is a faint linear
structure to the North, which coincides with the main radio jet. An X-ray
deficit in the corresponding region suggests an interaction between the cluster
medium and the jet driven by the active nucleus.

</DOC>
<DOC>
<DOCNO> 102125 </DOCNO>
Another realization of the category of modules over the small quantum


  Let $g$ be a semi-simple simply-connected Lie algebra and let $U_\ell$ be the
corresponding quantum group with divided powers, where $\ell$ is an even order
root of unity. Let in addition $u_\ell\subset U_\ell$ be the corresponding
"small" quantum group.
  In this paper we establish the following relation between the categories of
representations of $U_\ell$ and $u_\ell$: We show that the category of
$u_\ell$-modules is naturally equivalent to the category of $U_\ell$-modules,
which have a {\it Hecke eigen-property} with respect to representations lifted
by means of the quantum Frobenius map $U_\ell\ti U(\check g)$, where $g$ is the
Langlands dual Lie algebra.
  This description allows to express the regular linkage class in the category
$u_\ell$-mod in terms of perverse sheaves on the affine flag variety with a
Hecke eigen-property. Moreover, it can serve as a basis to the program to
understand the connection between the category $u_\ell$-mod and the category of
representations of the corresponding affine algebra at the critical level.

</DOC>
<DOC>
<DOCNO> 169917 </DOCNO>
An Introduction to Quantum Error Correction


  Quantum states are very delicate, so it is likely some sort of quantum error
correction will be necessary to build reliable quantum computers. The theory of
quantum error-correcting codes has some close ties to and some striking
differences from the theory of classical error-correcting codes. Many quantum
codes can be described in terms of the stabilizer of the codewords. The
stabilizer is a finite Abelian group, and allows a straightforward
characterization of the error-correcting properties of the code. The stabilizer
formalism for quantum codes also illustrates the relationships to classical
coding theory, particularly classical codes over GF(4), the finite field with
four elements.

</DOC>
<DOC>
<DOCNO> 101442 </DOCNO>
The Geography of Spin Symplectic 4-Manifolds


  In this paper we construct a family of simply connected, spin, non-complex,
symplectic 4-manifolds which cover all but finitely many allowed lattice points
$(\chi, c)$ lying in $0 \leq c \leq 8.76\chi$. Furthermore, as a corollary, we
prove that there exist infinitely many exotic smooth structures on $(2n+1)(S^2
\times S^2)$ for all n large enough.

</DOC>
<DOC>
<DOCNO> 150993 </DOCNO>
Black Holes in Supergravity and String Theory


  We give an elementary introduction to black holes in supergravity and string
theory. The focus is on BPS solutions in four- and higher-dimensional
supergravity and string theory. Basic ideas and techniques are explained in
detail, including exercises with solutions.

</DOC>
<DOC>
<DOCNO> 100845 </DOCNO>
Skein construction of idempotents in Birman-Murakami-Wenzl algebras


  We give skein theoretic formulas for minimal idempotents in the
Birman-Murakami-Wenzl algebras. These formulas are then applied to derive
various known results needed in the construction of quantum invariants and
modular categories. In particular, an elementary proof of the Wenzl formula for
quantum dimensions is given. This proof does not use the representation theory
of quantum groups and the character formulas.

</DOC>
<DOC>
<DOCNO> 150453 </DOCNO>
Toric Calabi-Yau Fourfolds, Duality Between N=1 Theories and Divisors


  We study issues related to F-theory on Calabi-Yau fourfolds and its duality
to heterotic theory for Calabi-Yau threefolds. We discuss principally fourfolds
that are described by reflexive polyhedra and show how to read off some of the
data for the heterotic theory from the polyhedron. We give a procedure for
constructing examples with given gauge groups and describe some of these
examples in detail. Interesting features arise when the local pieces are fitted
into a global manifold. An important issue is how to compute the superpotential
explicitly. Witten has shown that the condition for a divisor to contribute to
the superpotential is that it have arithmetic genus 1. Divisors associated with
the short roots of non-simply laced gauge groups do not always satisfy this
condition while the divisors associated to all other roots do. For such a
`dissident' divisor we distinguish cases for which the arithmetic genus is
greater than unity corresponding to an X that is not general in moduli (in the
toric case this corresponds to the existence of non-toric parameters). In these
cases the `dissident' divisor D does not remain an effective divisor for
general complex structure. If however the arithmetic genus is less than or
equal to 0, then the divisor is general in moduli and there is a genuine
instability.

</DOC>
<DOC>
<DOCNO> 120949 </DOCNO>
The X-Ray Absorber in Broad Absorption Line Quasars


  Recent observations of Broad Absorption Line (BAL) quasars demonstrated that
the soft X-ray emission of these objects is extremely weak and convincing
evidence for very strong absorption by a high column density (~ 10^23.5 cm^-2)
was obtained for PG 1411+442, even though it is one of the few BAL QSOs
strongly detected in soft X-rays. This paper examines the ionization status and
geometry of the X-ray absorber by combining the properties of the UV lines with
the X-ray continuum absorption. We show that the gas has to have large column
densities in ions of major UV absorption lines, such as CIV, NV, OVI and Ne
VIII, in order to have sufficient opacity around 0.2 to 0.35 keV. The UV
absorption lines have to be saturated if the X-ray absorber intersects the line
of sight to the UV continuum emission region. A uniformly covering UV and X-ray
absorption model can be constructed for PG 1411+442 but in some other soft
X-ray detected BAL QSOs, such as PG 1001+054, the observed line optical depth
is much lower than expected from the X-ray absorbing material. We propose a
scheme in which a substantial fraction of the line of sight to the continuum
source may be covered by either an optically thick flow or clouds in a narrow
velocity range, but in which the total covering factor of either the whole flow
or all clouds is close to unity.

</DOC>
<DOC>
<DOCNO> 80918 </DOCNO>
The Perfect Laplace Operator for Non-Trivial Boundaries


  The application of Renormalization Group (RG) methods to find perfect
discretizations of partial differential equations is a promising but little
investigated approach. We calculate the classically perfect fixed-point Laplace
operator for boundaries of non-trivial shape analytically and numerically and
present a parametrization that can be used for solving the Poisson equation.

</DOC>
<DOC>
<DOCNO> 118403 </DOCNO>
Non-detection of a pulsar-powered nebula in Puppis A, and implications


  We report on a deep radio search for a pulsar wind nebula associated with the
radio-quiet neutron star RX J0822-4300 in the supernova remnant Puppis A. The
well-determined properties of Puppis A allow us to constrain the size of any
nebula to less than 30 arcsec; however we find no evidence for such a source on
any spatial scale up to 30 arcmin. These non-detections result in an upper
limit on the radio luminosity of any pulsar-powered nebula which is three
orders of magnitude below what would be expected if RX J0822-4300 was an
energetic young radio pulsar beaming away from us, and cast doubt on a recent
claim of X-ray pulsations from this source. The lack of a radio nebula leads us
to conclude that RX J0822-4300 has properties very different from most young
radio pulsars, and that it represents a distinct population which may be as
numerous, or even more so, than radio pulsars.

</DOC>
<DOC>
<DOCNO> 119569 </DOCNO>
Decaying Cold Dark Matter Model and Small-Scale Power


  The canonical cosmological constant dominated cold dark matter model (LCDM)
may possess too much power on small scales at z=0, manifested as central
over-concentration of dark matter and over-abundance of dwarf galaxies. We
suggest an alternative model, LDCDM, where one half of the cold dark matter
particles decay into relativistic particles by z=0. The model successfully
lowers the concentration of dark matter in dwarf galaxies as well as in large
galaxies like our own at low redshift, while simultaneously retaining the
virtues of the LCDM model. The model solves the problem of over-production of
small dwarf galaxies in the LCDM not by removing them but by identifying them
with failed, "dark" galaxies, where star-formation is quenched due to dark
matter evaporation and consequent halo expansion. A dramatic difference between
the LDCDM model and other proposed variants of the LCDM model is that the
small-scale power at high redshift (z>2) in the LDCDM model is enhanced
compared to the LCDM model.
  A COBE-and-cluster normalized LDCDM model can be constructed with the
following parameters: H0=60km/sec/Mpc, lambda0=0.60, Omega_{0,CDM}=0.234,
Omega_{0,b}=0.044, n=1.0, and sigma8=1.06. A clean test of this model can be
made by measuring the evolution of gas fraction in clusters. The prediction is
that the gas fraction should decrease with redshift and is smaller by 31% at
z=1 than at z=0. X-ray and Sunyaev-Zel'dovich effect observations should
provide such a test.

</DOC>
<DOC>
<DOCNO> 9422 </DOCNO>
Magnetic Coherence as a Universal Feature of Cuprate Superconductors


  Recent inelastic neutron scattering (INS) experiments on
La$_{2-x}$Sr$_x$CuO$_4$ have established the existence of a {\it magnetic
coherence effect}, i.e., strong frequency and momentum dependent changes of the
spin susceptibility, $\chi''$, in the superconducting phase. We show, using the
spin-fermion model for incommensurate antiferromagnetic spin fluctuations, that
the magnetic coherence effect establishes the ability of INS experiments to
probe the electronic spectrum of the cuprates, in that the effect arises from
the interplay of an incommensurate magnetic response, the form of the
underlying Fermi surface, and the opening of the d-wave gap in the fermionic
spectrum. In particular, we find that the magnetic coherence effect observed in
INS experiments on La$_{2-x}$Sr$_x$CuO$_4$ requires that the Fermi surface be
closed around $(\pi,\pi)$ up to optimal doping. We present several predictions
for the form of the magnetic coherence effect in YBa$_2$Cu$_3$O$_{6+x}$ in
which an incommensurate magnetic response has been observed in the
superconducting state.

</DOC>
<DOC>
<DOCNO> 174483 </DOCNO>
The Emission Pattern of High-Energy Pions: A New Probe for the Early


  The emission pattern of charged pions has been measured in Au+Au collisions
at 1 GeV/nucleon incident energy. In peripheral collisions and at target
rapidities, high-energy pions are emitted preferentially towards the target
spectator matter. In contrast, low-energy pions are emitted predominantly in
the opposite direction. The corresponding azimuthal anisotropy is explained by
the interaction of pions with projectile and target spectator matter. This
interaction with the spectator matter causes an effective shadowing which
varies with time during the reaction. Our observations show that high-energy
pions stem from the early stage of the collision whereas low-energy pions
freeze out later.

</DOC>
<DOC>
<DOCNO> 70879 </DOCNO>
Criticality in quark-gluon systems far beyond thermal and chemical


  Experimental evidence and theoretical arguments for the existence of
self-organized criticality in systems of gluons and quarks are presented. It is
observed that the existing data for high-transverse-momentum jet-production
exhibit striking regularities; and it is shown that, together with
first-principle considerations, such regularities can be used, not only to
probe the possible compositness of quarks, but also to obtain {\em direct
evidence} for, or against, the existence of critical temperature and/or
critical chemical potential in quark-gluon systems when hadrons are squeezed
together.

</DOC>
<DOC>
<DOCNO> 71939 </DOCNO>
Can we distinguish SUSY breaking terms between weakly and strongly


  We study soft SUSY breaking terms in heterotic M-theory. We show that both
weakly and strongly coupled heterotic string models lead to the same relations
of soft SUSY breaking terms, $A=-M$ and $m^2 = M^2/3$, up to $O((\alpha
T/S)^2)$.

</DOC>
<DOC>
<DOCNO> 151538 </DOCNO>
Explicit Derivation of Yang-Mills Self-Dual Solutions on non-Commutative


  We develop the noncommutative harmonic space (NHS) analysis to study the
problem of solving the non-linear constraint eqs of noncommutative Yang-Mills
self-duality in four-dimensions. We show that this space, denoted also as
NHS($\eta,\theta$), has two SU(2) isovector deformations $\eta^{(ij)}$ and
$\theta^{(ij)}$ parametrising respectively two noncommutative harmonic
subspaces NHS($\eta,0$) and NHS($0,\theta$) used to study the self-dual and
anti self-dual noncommutative Yang-Mills solutions. We formulate the Yang-Mills
self-dual constraint eqs on NHS($\eta,0$) by extending the idea of harmonic
analyticity to linearize them. Then we give a perturbative self-dual solution
recovering the ordinary one. Finally we present the explicit computation of an
exact self-dual solution.

</DOC>
<DOC>
<DOCNO> 83382 </DOCNO>
Combining Linguistic and Spatial Information for Document Analysis


  We present a framework to analyze color documents of complex layout. In
addition, no assumption is made on the layout. Our framework combines in a
content-driven bottom-up approach two different sources of information: textual
and spatial. To analyze the text, shallow natural language processing tools,
such as taggers and partial parsers, are used. To infer relations of the
logical layout we resort to a qualitative spatial calculus closely related to
Allen's calculus. We evaluate the system against documents from a color journal
and present the results of extracting the reading order from the journal's
pages. In this case, our analysis is successful as it extracts the intended
reading order from the document.

</DOC>
<DOC>
<DOCNO> 169820 </DOCNO>
Improved two-party and multi-party purification protocols


  We present an improved protocol for entanglement purification of bipartite
mixed states using several states at a time rather than two at a time as in the
traditional recurrence method. We also present a generalization of the hashing
method to n-partite cat states, which achieves a finite yield of pure cat
states for any desired fidelity. Our results are compared to previous
protocols.

</DOC>
<DOC>
<DOCNO> 117057 </DOCNO>
Two-time Green function method in quantum electrodynamics of high-Z


  The two-time Green function method in quantum electrodynamics of high-Z
few-electron atoms is described in detail. This method provides a simple
procedure for deriving formulas for the energy shift of a single level and for
the energies and wave functions of degenerate and quasi-degenerate states. It
also allows one to derive formulas for the transition and scattering
amplitudes. Application of the method to resonance scattering processes yields
a systematic theory for the spectral line shape. The practical ability of the
method is demonstrated by deriving formulas for the QED and
interelectronic-interaction corrections to energy levels and transition and
scattering amplitudes in one-, two-, and three-electron atoms. Numerical
calculations of the Lamb shift, the hyperfine splitting, the bound-electron g
factor, and the radiative recombination cross section in heavy ions are also
reviewed.

</DOC>
<DOC>
<DOCNO> 152487 </DOCNO>
Fermion-induced effective action in the presence of a static


  We present a numerical study of the fermion-induced effective action in the
presence of a static inhomogeneous magnetic field for both 3+1 and 2+1
dimensional QED using a novel approach. This approach is appropriate for
cylindrically symmetric magnetic fields with finite magnetic flux $\Phi$. We
consider families of magnetic fields, dependent on two parameters, a typical
value $B_{m}$ for the field and a typical range d. We investigate the behavior
of the effective action for three distinct cases: 1) keeping $\Phi$ (or
$B_{m}d^{2}$) constant and varying d, 2) keeping $B_{m}$ constant and varying d
and 3) keeping d constant and varying $\Phi$ (or $B_{m}d^{2}$). We note an
interesting difference as d tends to infinity (case 2) between smooth and
discontinuous magnetic fields. In the strong field limit (case 3) we also
derive an explicit asymptotic formula for the 3+1 dimensional action. We study
the stability of the magnetic field and we show that magnetic fields of the
type we examine remain unstable, even in the presence of the fermions. In the
appropriate regions we check our numerical results against the Schwinger
formula (constant magnetic field), the derivative expansion and the numerical
work of M. Bordag and K. Kirsten. The role of the Landau levels for the
effective action, and the appearance of metastable states for large magnetic
flux, are discussed in an appendix.

</DOC>
<DOC>
<DOCNO> 12875 </DOCNO>
Quantum superconductor-metal transition in a proximity array


  A theory of the zero-temperature superconductor-metal transition is developed
for an array of superconductive islands (of size d) coupled via a disordered
two-dimensional conductor with the dimensionless conductance g>>1. At T=0
macroscopically superconductive state of the array with the lattice spacing
b>>d is destroyed at g < g_c \approx 0.1 ln^2(b/d). At high temperatures the
normal-state resistance between neighboring islands at b=b_c is much smaller
than h/4e^2.

</DOC>
<DOC>
<DOCNO> 151655 </DOCNO>
Symmetry, Duality and Anholonomy of Point Interactions in One Dimension


  We analyze the spectral structure of the one dimensional quantum mechanical
system with point interaction, which is known to be parametrized by the group
U(2). Based on the classification of the interactions in terms of symmetries,
we show, on a general ground, how the fermion-boson duality and the spectral
anholonomy recently discovered can arise. A vital role is played by a hidden
su(2) formed by a certain set of discrete transformations, which becomes a
symmetry if the point interaction belongs to a distinguished U(1) subfamily in
which all states are doubly degenerate. Within the U(1), there is a particular
interaction which admits the interpretation of the system as a supersymmetric
Witten model.

</DOC>
<DOC>
<DOCNO> 69010 </DOCNO>
The Super - Kamiokande Day - Night Effect Data and the MSW Solutions of


  The current Super-Kamiokande data on the D-N asymmetry between the the day
event rate and the {\it Night} and {\it Core} event rates, produced by solar
neutrinos which respectively cross the Earth along any trajectory and cross the
Earth core before reaching the detector, imply rather stringent constraints on
the MSW small mixing angle (SMA) $\nu_e \to \nu_{\mu(\tau)}$ solution of the
solar neutrino problem. A simplified analysis shows, in particular, that a
substantial subregion of the SMA solution region is disfavored by these data.
The {\it Core} D-N asymmetry data alone allow to rule out at 99.7% C.L. a part
of this subregion. The constraints on the MSW large mixing angle and LOW $\nu_e
\to \nu_{\mu(\tau)}$ solutions as well as on the MSW $\nu_e \to \nu_{s}$
solution, following from the data on the {\it Night} and {\it Core} D-N
asymmetries are also discussed.

</DOC>
<DOC>
<DOCNO> 40312 </DOCNO>
The Hadronic Picture of the Photon


  The hadronic interactions of the photon are studied in terms of new
measurements of the total hadronic cross section and di-jet production in
photon-photon collisions at LEP2.

</DOC>
<DOC>
<DOCNO> 178668 </DOCNO>
Properties of the predicted super-deformed band in ^{32}S


  Properties like the excitation energy with respect to the ground state,
moments of inertia, B(E2) transition probabilities and stability against
quadrupole fluctuations at low spin of the predicted superdeformed band of
^{32}S are studied with the Gogny force D1S using the angular momentum
projected generator coordinate method for the axially symmetric quadrupole
moment. The Self Consistent Cranking method is also used to describe the
superdeformed rotational band. In addition, properties of some collective
normal deformed states are discussed.

</DOC>
<DOC>
<DOCNO> 13905 </DOCNO>
A New Heavy-Fermion Superconductor CeIrIn5: Relative of the Cuprates?


  CeIrIn5 is a member of a new family of heavy-fermion compounds and has a
Sommerfeld specific heat coefficient of 720 mJ/mol-K2. It exhibits a bulk,
thermodynamic transition to a superconducting state at Tc=0.40 K, below which
the specific heat decreases as T2 to a small residual T-linear value.
Surprisingly, the electrical resistivity drops below instrumental resolution at
a much higher temperature T0=1.2 K. These behaviors are highly reproducible and
field-dependent studies indicate that T0 and Tc arise from the same underlying
electronic structure. The layered crystal structure of CeIrIn5 suggests a
possible analogy to the cuprates in which spin/charge pair correlations develop
well above Tc.

</DOC>
<DOC>
<DOCNO> 118356 </DOCNO>
The extragalactic background and its fluctuations in the far-infrared


  A Cosmic Far-InfraRed Background (CFIRB) has long been predicted that would
traces the intial phases of galaxy formation. It has been first detected by
Puget et al.(1996) using COBE data and has been later confirmed by several
recent studies (Fixsen et al. 1998, Hauser et al. 1998, Lagache et al. 1999).
We will present a new determination of the CFIRB that uses for the first time,
in addition to COBE data, two independent gas tracers: the HI survey of
Leiden/Dwingeloo (hartmann, 1998) and the WHAM H$_{\alpha}$ survey (Reynolds et
al 1998). We will see that the CFIRB above 100 micron is now very well
constrained. The next step is to see if we can detect its fluctuations. To
search for the CFIRB fluctuations, we have used the FIRBACK observations.
FIRBACK is a deep cosmological survey conducted at 170 micron with ISOPHOT
(Dole et al., 2000). We show that the emission of unresolved extra-galactic
sources clearly dominates, at arcminute scales, the background fluctuations in
the lowest galactic emission regions. This is the first detection of the CFIRB
fluctuations.

</DOC>
<DOC>
<DOCNO> 100933 </DOCNO>
Orthogonal matrices with rational components in composing tests for High


  Fermat Last Theorem, which inspired mathematicians during 300 years, is
proved by Andrew Wiles. Even among mathematicians there is a narrow circle of
specialists, who can read this proof and understand all details. Is it a reason
for pessimism? No, since arithmetics if entire numbers contains broad variety
of problems with a simple statement, which might be not less intricate. One of
them arises in elementary geometry.

</DOC>
<DOC>
<DOCNO> 85056 </DOCNO>
Loop Quantum Cosmology III: Wheeler-DeWitt Operators


  In the framework of loop quantum cosmology anomaly free quantizations of the
Hamiltonian constraint for Bianchi class A, locally rotationally symmetric and
isotropic models are given. Basic ideas of the construction in (non-symmetric)
loop quantum gravity can be used, but there are also further inputs because the
special structure of symmetric models has to be respected by operators. In
particular, the basic building blocks of the homogeneous models are point
holonomies rather than holonomies necessitating a new regularization procedure.
In this respect, our construction is applicable also for other
(non-homogeneous) symmetric models, e.g. the spherically symmetric one.

</DOC>
<DOC>
<DOCNO> 100887 </DOCNO>
A Little Microlocal Morse Theory


  If a complex analytic function, $f$, has a stratified isolated critical
point, then it is known that the cohomology of the Milnor fibre of $f$ has a
direct sum decomposition in terms of the normal Morse data to the strata. We
use microlocal Morse theory to obtain the same result under the weakened
hypothesis that the vanishing cycles along $f$ have isolated support. We also
investigate an index-theoretic proof of this fact.

</DOC>
<DOC>
<DOCNO> 9515 </DOCNO>
Slow dynamics of Ising models with energy barriers


  Using Monte Carlo simulations we study the dynamics of three-dimensional
Ising models with nearest-, next-nearest-, and four-spin (plaquette)
interactions. During coarsening, such models develop growing energy barriers,
which leads to very slow dynamics at low temperature. As already reported, the
model with only the plaquette interaction exhibits some of the features
characteristic of ordinary glasses: strong metastability of the supercooled
liquid, a weak increase of the characteristic length under cooling,
stretched-exponential relaxation and aging. The addition of two-spin
interactions, in general, destroys such behaviour: the liquid phase loses
metastability and the slow-dynamics regime terminates well below the melting
transition, which is presumably related with a certain corner-rounding
transition. However, for a particular choice of interaction constants, when the
ground state is strongly degenerate, our simulations suggest that the
slow-dynamics regime extends up to the melting transition. The analysis of
these models leads us to the conjecture that in the four-spin Ising model
domain walls lose their tension at the glassy transition and that they are
basically tensionless in the glassy phase.

</DOC>
<DOC>
<DOCNO> 117960 </DOCNO>
Properties of spherical galaxies and clusters with an NFW density


  Using the standard dynamical theory of spherical systems, we calculate the
properties of spherical galaxies and clusters whose density profiles obey the
universal form first obtained in high resolution cosmological N-body
simulations by Navarro, Frenk & White. We adopt three models for the internal
kinematics: isotropic velocities, constant anisotropy and increasingly radial
Osipkov-Merritt anisotropy. Analytical solutions are found for the radial
dependence of the mass, gravitational potential, velocity dispersion, energy
and virial ratio and we test their variability with the concentration parameter
describing the density profile and amount of velocity anisotropy. We also
compute structural parameters, such as half-mass radius, effective radius and
various measures of concentration. Finally, we derive projected quantities, the
surface mass density and line-of-sight as well as aperture velocity dispersion,
all of which can be directly applied in observational tests of current
scenarios of structure formation. On the mass scales of galaxies, if constant
mass-to-light is assumed, the NFW surface density profile is found to fit well
Hubble-Reynolds laws. It is also well fitted by Sersic R^(1/m) laws, for m ~ 3,
but in a much narrower range of m and with much larger effective radii than are
observed. Assuming in turn reasonable values of the effective radius, the mass
density profiles imply a mass-to-light ratio that increases outwards at all
radii.

</DOC>
<DOC>
<DOCNO> 67987 </DOCNO>
Charmonium Production from the Secondary Collisions at LHC Energy


  We consider the charmonium production in thermalized hadronic medium created
in ultrarelativistic heavy ion collisions at LHC energy.
  The calculations for the secondary $J/\psi$ and $\psi^,$ production by $D\bar
D$ annihilation are performed within a kinetic model taking into account the
space-time evolution of a longitudinally and transversely expanding medium. We
show that the secondary charmonium production appears almost entirely during
the mixed phase and it is very sensitive to the charmonium dissociation cross
section with co-moving hadrons. Within the most likely scenario for the
dissociation cross section of the $J/\psi$ mesons their regeneration in the
hadronic medium will be negligible. The secondary production of $\psi^,$ mesons
however, due to their large cross section above the threshold, can
substantially exceed the primary yield.

</DOC>
<DOC>
<DOCNO> 11062 </DOCNO>
Stochastic Penna model for biological aging


  A stochastic genetic model for biological aging is introduced bridging the
gap between the bit-string Penna model and the Pletcher-Neuhauser approach. The
phenomenon of exponentially increasing mortality function at intermediate ages
and its deceleration at advanced ages is reproduced for both the evolutionary
steady-state population and the genetically homogeneous individuals.

</DOC>
<DOC>
<DOCNO> 122009 </DOCNO>
Irradiance or luminosity changes?


  Whereas a variation of the solar luminosity, L, will inevitably cause a
similar change of the total solar irradiance, S, the opposite is not true. In
fact, the bulk of the days to months variations of S can be explained entirely
in terms of the passage of active regions across the solar disk. In this case,
L remains essentially unchanged.
  For the total irradiance variation observed over the solar cycle, the issue
is more uncertain. One view explains this modulation primarily as a combined
action of active regions and magnetic network. These components would be
superposed to an otherwise unchanging photosphere. the other view suggests that
the activity cycle modulation of S is primarily produced by a variation of L
(both in terms of R and T_{eff}) caused by structural reajustments of the
interior of the Sun induced by a changing magnetic field. We will present
evidence in support of this second interpretation, and a model for it. We will
also present the S variations over the last 5 centuries implied by our model.

</DOC>
<DOC>
<DOCNO> 178679 </DOCNO>
Two pion electroproduction


  We have extended a model for the $\gamma N\to \pi\pi N$ reaction to virtual
photons and selected the diagrams which have a $\Delta$ in the final state. The
agreement found with the $\gamma_v p\to\Delta^0\pi^+$ and $\gamma_v
p\to\Delta^{++}\pi^-$ reactions is good. The sensitivity of the results to
$N\Delta$ transition form factors is also studied. The present reaction,
selecting a particular final state, is an extra test for models of the
$\gamma_{v} N\to \pi\pi N$ amplitude.

</DOC>
<DOC>
<DOCNO> 101704 </DOCNO>
The Geometry of Metrical Multi-time Lagrange Spaces


  A geometrization of a Kronecker $h$-regular multi-time Lagrangian function
with partial derivatives of order one is described, in the sense of
d-connections, d-torsions and d-curvatures.

</DOC>
<DOC>
<DOCNO> 99707 </DOCNO>
On the signatures of even 4-manifolds


  In this paper, we prove a number of inequalities between the signature and
the Betti numbers of a 4-manifold with even intersection form. Furthermore, we
introduce a new geometric group invariant and discuss some of its properties.

</DOC>
<DOC>
<DOCNO> 84525 </DOCNO>
Transformations of units and world's geometry


  The issue of the transformations of units is treated, mainly, in a
geometrical context. It is shown that Weyl-integrable geometry is a consistent
framework for the formulation of the gravitational laws since the basic law on
which this geometry rests is invariant under point-dependent transformations of
units. Riemann geometry does not fulfill this requirement. Spacetime
singularities are then shown to be a consequence of a wrong choice of the
geometrical formulation of the laws of gravitation. This result is discussed,
in particular, for the Schwrazschild black hole and for
Friedmann-Robertson-Walker cosmology. Arguments are given that point at
Weyl-integrable geometry as a geometry implicitly containing the quantum
effects of matter. The notion of geometrical relativity is presented. This
notion may represent a natural extension of general relativity to include
invariance under the group of units transformations.

</DOC>
<DOC>
<DOCNO> 12668 </DOCNO>
Transition-metal interactions in aluminum-rich intermetallics


  The extension of the first-principles generalized pseudopotential theory
(GPT) to transition-metal (TM) aluminides produces pair and many-body
interactions that allow efficient calculations of total energies. In
aluminum-rich systems treated at the pair-potential level, one practical
limitation is a transition-metal over-binding that creates an unrealistic TM-TM
attraction at short separations in the absence of balancing many-body
contributions. Even with this limitation, the GPT pair potentials have been
used effectively in total-energy calculations for Al-TM systems with TM atoms
at separations greater than 4 AA. An additional potential term may be added for
systems with shorter TM atom separations, formally folding repulsive
contributions of the three- and higher-body interactions into the pair
potentials, resulting in structure-dependent TM-TM potentials. Towards this
end, we have performed numerical ab-initio total-energy calculations using VASP
(Vienna Ab Initio Simulation Package) for an Al-Co-Ni compound in a particular
quasicrystalline approximant structure. The results allow us to fit a
short-ranged, many-body correction of the form a(r_0/r)^{b} to the GPT pair
potentials for Co-Co, Co-Ni, and Ni-Ni interactions.

</DOC>
<DOC>
<DOCNO> 7856 </DOCNO>
Direct Coulomb and Exchange Interaction in Artificial Atoms


  We determine the contributions from the direct Coulomb and exchange
interactions to the total interaction in semiconductor artificial atoms. We
tune the relative strengths of the two interactions and measure them as a
function of the number of confined electrons. We find that electrons tend to
have parallel spins when they occupy nearly degenerate single-particle states.
We use a magnetic field to adjust the single-particle state degeneracy, and
find that the spin-configurations in an arbitrary magnetic field are well
explained in terms of two-electron singlet and triplet states.

</DOC>
<DOC>
<DOCNO> 120728 </DOCNO>
First results of UVES at VLT: revisiting RR Tel


  We present here the first results of UVES observations of RR Tel. The
exceptional performances of the instrument have allowed the detection of new
spectral features and have led to an improvement in the identifications of
several emission lines. A direct comparison with the IUE observations in the
range 3045-3300 A has revealed the appearance of many weak and shallow lines,
most of them lacking a convincing identification. The Balmer lines are visible
up to H38 and are accompanied by the He II lines of the Pickering series. Also,
all of the He II emissions of the Pfund series, from 5858 A to 6408 A have been
detected. We made definite identifications of additional TiO bands at 4955 A
(alpha R_2 1-0), 5167 A (alpha R_2 0-0), 5445 A (alpha R_2 0-1), 5598 A (beta
R_1 0-0), 5847 A (gamma 'R_1 1-0), and 6148 A (gamma ' {^S} R_21 0-0). The
Halpha line has very wide wings, extending to at least 5000 km/s, which are
similar to those reported for the planetary nebula IC 4997 and attributed to
Raman scattering by Ly beta photons. A selective pumping mechanism via the HeII
237 A emission is proposed to explain the intensity of the high-lying lines of
O IV mult. 1 and 2.

</DOC>
<DOC>
<DOCNO> 100350 </DOCNO>
Time symmetry in Rigged Hilbert Spaces


  Despite the fact that the fundamental physical laws are symmetric in time,
most observed processes do not show this symmetry. Especially the phenomenon of
decay seems to involve a kind of irreversibility that makes the definition of a
microscopic arrow of time possible. Such an intrinsic irreversibility is
incorporated within the Rigged Hilbert Space quantum mechanics of the Brussels
School, contrasting to the statements of standard quantum mechanics. As shown
in this paper, the formalism bears significant advantages in the description of
decaying systems, however the breaking of time symmetry can be avoided.

</DOC>
<DOC>
<DOCNO> 83350 </DOCNO>
An Experimental Comparison of Naive Bayesian and Keyword-Based Anti-Spam


  The growing problem of unsolicited bulk e-mail, also known as "spam", has
generated a need for reliable anti-spam e-mail filters. Filters of this type
have so far been based mostly on manually constructed keyword patterns. An
alternative approach has recently been proposed, whereby a Naive Bayesian
classifier is trained automatically to detect spam messages. We test this
approach on a large collection of personal e-mail messages, which we make
publicly available in "encrypted" form contributing towards standard
benchmarks. We introduce appropriate cost-sensitive measures, investigating at
the same time the effect of attribute-set size, training-corpus size,
lemmatization, and stop lists, issues that have not been explored in previous
experiments. Finally, the Naive Bayesian filter is compared, in terms of
performance, to a filter that uses keyword patterns, and which is part of a
widely used e-mail reader.

</DOC>
<DOC>
<DOCNO> 102644 </DOCNO>
Fractional Super Lie Algebras and Groups


  n^{th} root of a Lie algebra and its dual (that is fractional supergroup)
based on the permutation group $S_n$ invariant forms are formulated in the Hopf
algebra formalism. Detailed discussion of $S_3$-graided $sl(2)$ algebras is
done.

</DOC>
<DOC>
<DOCNO> 170503 </DOCNO>
Vacuum Induced Coherences in Radiatively Coupled Multilevel Systems


  We show that radiative coupling between two multilevel atoms having
near-degenerate states can produce new interference effects in spontaneous
emission. We explicitly demonstrate this possibility by considering two
identical V systems each having a pair of transition dipole matrix elements
which are orthogonal to each other. We discuss in detail the origin of the new
interference terms and their consequences. Such terms lead to the evolution of
certain coherences and excitations which would not occur otherwise. The special
choice of the orientation of the transition dipole matrix elements enables us
to illustrate the significance of vacuum induced coherence in multi-atom
multilevel systems. These coherences can be significant in energy transfer
studies.

</DOC>
<DOC>
<DOCNO> 121656 </DOCNO>
Central Elemental Abundance Ratios in the Perseus Cluster: Resonant


  We have determined elemental abundance ratios in the core of the Perseus
cluster for several elements. These ratios indicate a central dominance of SN
Ia ejecta similar to that found for A496, A2199 and A3571 (Dupke & White 2000).
Simultaneous analysis of ASCA spectra from SIS1, GIS 2&3 shows that the ratio
of Ni to Fe abundances is ~ (3.4 +- 1.1) times Solar within the central 4'.
This ratio is consistent with (and more precise than) that observed in other
clusters whose central regions are dominated by SN Ia ejecta. Such a large Ni
over-abundance is predicted by "Convective Deflagration" explosion models for
SN Ia such as "W7" but is inconsistent with delayed detonation models. We note
that with current instrumentation the NiK(alpha) line is confused with
FeK(beta) and that the Ni over-abundance we observe has been interpreted by
others as an anomalously large ratio of FeK(beta) to FeK(alpha) caused by
resonant scattering in the FeK(alpha) line. We argue that a central enhancement
of SN Ia ejecta and hence a high ratio of Ni to Fe is naturally explained by
scenarios that include the generation of chemical gradients by suppressed SN Ia
winds or ram-pressure stripping of cluster galaxies. It is not necessary to
suppose that the intracluster gas is optically thick to resonant scattering of
the FeK(alpha) line.

</DOC>
<DOC>
<DOCNO> 10441 </DOCNO>
Asians and cash dividends: Exploiting symmetries in pricing theory


  In this article we present new results for the pricing of arithmetic Asian
options within a Black-Scholes context. To derive these results we make
extensive use of the local scale invariance that exists in the theory of
contingent claim pricing. This allows us to derive, in a natural way, a simple
PDE for the price of arithmetic Asians options. In the case of European average
strike options, a proper choice of numeraire reduces the dimension of this PDE
to one, leading to a PDE similar to the one derived by Rogers and Shi. We solve
this PDE, finding a Laplace-transform representation for the price of average
strike options, both seasoned and unseasoned. This extends the results of Geman
and Yor, who discussed the case of average price options. Next we use symmetry
arguments to show that prices of average strike and average price options can
be expressed in terms of each other. Finally we show, again using symmetries,
that plain vanilla options on stocks paying known cash dividends are closely
related to arithmetic Asians, so that all the new techniques can be directly
applied to this case.

</DOC>
<DOC>
<DOCNO> 100940 </DOCNO>
Astrophysical Dynamics 1999/2000: Merging Research and Education


  The workshop `Astrophysical Dynamics 1999/2000' followed a homonymous
advanced research course, and both activities were organized by me. In this
opening paper of the proceedings book, I describe them and document their
strong impact on the academic life of the local institutions. The advanced
research course was open to graduate students, senior researchers, and
motivated under-graduate students with good background in physics and
mathematics. The course covered several multi-disciplinary issues of modern
research on astrophysical dynamics, and thus also of interest to physicists,
mathematicians and engineers. The major topic was gas dynamics, viewed in
context with stellar dynamics and plasma physics. The course was complemented
by parallel seminars on hot topics given by experts in such fields, and open to
a wide scientific audience. In particular, I gave a friendly introduction to
wavelets, which are becoming an increasingly powerful tool not only for
processing signals and images but also for analysing fractals and turbulence,
and which promise to have important applications to dynamical modelling of disc
galaxies. The workshop was open to a wide scientific audience. The workshop
with published proceedings book was, as a matter of fact, the innovative form
of exam that I proposed for the advanced research course. The contributions
were refereed and their quality is high on average, exceptionally high in a few
cases. The advanced research course and the workshop all together produced
great enthusiasm in the students and welcomed the participation of a hundred
different people, which means an order of magnitude more than an average
graduate course at Chalmers University of Technology and G\"oteborg University.

</DOC>
<DOC>
<DOCNO> 70985 </DOCNO>
Electroweak Bubble Nucleation, Nonperturbatively


  We present a lattice method to compute bubble nucleation rates at radiatively
induced first order phase transitions, in high temperature, weakly coupled
field theories, nonperturbatively. A generalization of Langer's approach, it
makes no recourse to saddle point expansions and includes completely the
dynamical prefactor. We test the technique by applying it to the electroweak
phase transition in the minimal standard model, at an unphysically small Higgs
mass which gives a reasonably strong phase transition (lambda/g^2 =0.036, which
corresponds to m(Higgs)/m(W) = 0.54 at tree level but does not correspond to a
positive physical Higgs mass when radiative effects of the top quark are
included), and compare the results to older perturbative and other estimates.
While two loop perturbation theory slightly under-estimates the strength of the
transition measured by the latent heat, it over-estimates the amount of
supercooling by a factor of 2.

</DOC>
<DOC>
<DOCNO> 100658 </DOCNO>
Hopf Differentials and the Images of Harmonic Maps


  Non-polynomial growth harmonic maps from the complex plane to the hyperbolic
space are studied. Some non-surjectivity results are obtained. Moreover, images
of such harmonic maps are investigated with reference to their Hopf
differentials.

</DOC>
<DOC>
<DOCNO> 68154 </DOCNO>
Final State Interactions and epsilon'/epsilon: A Critical Look


  We critically analyze recent attempts to include final state interaction
(FSI) effects in the calculation of the CP violating ratio epsilon'/epsilon. In
particular the approach of using the Muskhelishvili-Omnes equation for the
decay amplitudes is examined. We find that the values of the dispersive
correction factors are very sensitive to initial conditions which are, at
present, out of control, and demonstrate that the claimed large enhancement of
epsilon'/epsilon through FSI is questionable. We propose, instead, a different
implementation of this approach which may be useful to lattice determinations
of weak amplitudes.

</DOC>
<DOC>
<DOCNO> 13290 </DOCNO>
On the level spacing distribution in quantum graphs


  We derive a formula for the level spacing probability distribution in quantum
graphs. We apply it to simple examples and we discuss its relation with
previous work and its possible application in more general cases. Moreover, we
derive an exact and explicit formula for the level spacing distribution of
integrable quantum graphs.

</DOC>
<DOC>
<DOCNO> 152131 </DOCNO>
Supersymmetric R^4 actions and quantum corrections to superspace torsion


  We present the supersymmetrisation of the anomaly-related R^4 term in eleven
dimensions and show that it induces no non-trivial modifications to the
on-shell supertranslation algebra and the superspace torsion constraints before
inclusion of gauge-field terms.

</DOC>
<DOC>
<DOCNO> 9558 </DOCNO>
Wave Function Shredding by Sparse Quantum Barriers


  We discuss a model in which a quantum particle passes through $\delta$
potentials arranged in an increasingly sparse way. For infinitely many barriers
we derive conditions, expressed in terms ergodic properties of wave function
phases, which ensure that the point and absolutely continuous parts are absent
leaving a purely singularly continuous spectrum. For a finite number of
barriers, the transmission coefficient shows extreme sensitivity to the
particle momentum with fluctuation in many different scales. We discuss a
potential application of this behavior for erasing the information carried by
the wave function.

</DOC>
<DOC>
<DOCNO> 9004 </DOCNO>
Metal-insulator transitions in systems with electron-phonon and Coulomb


  We consider a model which includes the electron-phonon coupling to Ag or
Jahn-Teller Hg phonons, the Coulomb interaction U and an exchange integral K.
We study the metal-insulator transition for the integer fillings n=3 and 4. We
find that the coupling to Ag phonons increases the critical value Uc where the
transition takes place, while the coupling to Hg phonons decreases Uc. Without
electron-phonon coupling the Hund's rule coupling also decreases Uc. There is,
however, an interesting competition between the Hund's rule coupling and the
Jahn-Teller effect. Thus the reduction of Uc due to the Hg phonons becomes
smaller when the Hund's rule coupling is turned on. The implications of this is
discussed in the context of AnC60.

</DOC>
<DOC>
<DOCNO> 40376 </DOCNO>
First Year of the BABAR Experiment Data Taking


  The BABAR experiment at the PEP-II asymmetric B factory observed its first
hadronic events on the 26th of May 1999. We present the progress made so far on
the data taking, the BABAR detector performances and the physics analyses.

</DOC>
<DOC>
<DOCNO> 85223 </DOCNO>
Holographic Formulation of Quantum Supergravity


  We show that ${\cal N}=1$ supergravity with a cosmological constant can be
expressed as constrained topological field theory based on the supergroup
$Osp(1|4)$. The theory is then extended to include timelike boundaries with
finite spatial area. Consistent boundary conditions are found which induce a
boundary theory based on a supersymmetric Chern-Simons theory. The boundary
state space is constructed from states of the boundary supersymmetric
Chern-Simons theory on the punctured two sphere and naturally satisfies the
Bekenstein bound, where area is measured by the area operator of quantum
supergravity.

</DOC>
<DOC>
<DOCNO> 170349 </DOCNO>
Entropy lower bounds of quantum decision tree complexity


  We prove a general lower bound of quantum decision tree complexity in terms
of some entropy notion. We regard the computation as a communication process in
which the oracle and the computer exchange several rounds of messages, each
round consisting of O(log(n)) bits. Let E(f) be the Shannon entropy of the
random variable f(X), where X is uniformly random in f's domain. Our main
result is that it takes \Omega(E(f)) queries to compute any \emph{total}
function f. It is interesting to contrast this bound with the
\Omega(E(f)/log(n)) bound, which is tight for \emph{partial} functions. Our
approach is the polynomial method.

</DOC>
<DOC>
<DOCNO> 152612 </DOCNO>
Taming the supergravity description of non-BPS D-branes: the D/Dbar


  We obtain the supergravity solution which describes a bound state of
D-string/anti-D-string pairs attached to different fixed planes of an orbifold,
in type IIB string theory compactified on T^4/Z_2. For parameters at which the
conformal field theory point of view predicts stability, the solution displays
a repulson-like singularity. However, we observe that a D-string/anti-D-string
pair probe in this background becomes tensionless before reaching the
singularity, suggesting a resolution by the enhancon mechanism. Moreover, the
force feels by this probe is attractive, in contrast to the repulsive behaviour
observed in the non-BPS D-brane description.

</DOC>
<DOC>
<DOCNO> 71039 </DOCNO>
Comments on parton saturation at small x in large nuclei


  It is argued that the gluon density introduced by A.Mueller in relation to
the saturation phenomenon is different from the standardly defined one, which
turned out to have a soliton-like form in the numerical calculations. It is
shown that A.Mueller's densities obtained from the latter possess the same
saturation properties as originally predicted.

</DOC>
<DOC>
<DOCNO> 170774 </DOCNO>
Probabilistic Quantum Memories


  Typical address-oriented computer memories cannot recognize incomplete or
noisy information. Associative (content-addressable) memories solve this
problem but suffer from severe capacity shortages. I propose a model of a
quantum memory that solves both problems. The storage capacity is exponential
in the number of qbits and thus optimal. The retrieval mechanism for incomplete
or noisy inputs is probabilistic, with postselection of the measurement result.
The output is determined by a probability distribution on the memory which is
peaked around the stored patterns closest in Hamming distance to the input.

</DOC>
<DOC>
<DOCNO> 10412 </DOCNO>
Asymptotic Analysis of Diffuse-Layer Effects on Time-Dependent


  We investigate the subtle effects of diffuse charge on interfacial kinetics
by solving the governing equations for ion transport (Nernst-Planck) with
realistic boundary conditions representing reaction kinetics (Butler-Volmer)
and compact-layer capacitance (Stern) in the asymptotic limit $\epsilon =
\lambda_D/L \to 0$, where $\lambda_D$ is the Debye screening length and $L$ is
the distance between the working and counter electrodes. Using the methods of
singular perturbation theory, we derive the leading-order steady-state response
to a nonzero applied current in the case of the oxidation of a neutral species
into cations, without any supporting electrolyte. In certain parameter regimes,
the theory predicts a reaction-limited current smaller than the classical
diffusion-limited current. We also analyze the impedance of the electrochemical
cell when a small AC current modulation is added to an applied DC current. At
sufficiently high AC frequencies, the Maxwell displacement current is found to
exceed the Faradaic conduction current, and experimentally observed ``negative
impedances'' (out of phase AC voltage responses) are predicted close to the
reaction-limited current. Overall, we demonstrate that the dynamics of diffuse
charge plays a fundamental role in nonequilibrium surface reactions when the
transport of one of the reacting species is coupled to the total interfacial
reponse of the compact and diffuse layers.

</DOC>
<DOC>
<DOCNO> 117745 </DOCNO>
The MACHO Project 9 Million Star Color-Magnitude Diagram of the Large


  We present a 9 million star color-magnitude diagram (9M CMD) of the LMC bar.
The 9M CMD reveals a complex superposition of different age and metallicity
stellar populations, with important stellar evolutionary phases occurring over
3 orders of magnitude in number density. First, we count the non-variable
supergiants, the associated Cepheids, and measure the effective temperatures
defining the instability strip. Lifetime predictions of stellar evolution
theory are tested, with implications for the origin of low-luminosity Cepheids.
The highly-evolved AGB stars have a bimodal distribution in brightness, which
we interpret as discrete old populations (>1 Gyr). The faint AGB may be
metal-poor and very old. We identify the clusters NGC 411 and M3 as templates
for the admixture of old stellar populations. However, there are indications
that the old and metal-poor field population has a red HB morphology: the RR
Lyraes lie on the red edge of the instability strip, the AGB-bump is very red,
and the ratio of AGB-bump stars to RR Lyraes is quite large. If the HB second
parameter is age, the old and metal-poor field population likely formed after
the oldest clusters. Lifetime predictions of stellar evolution theory lead us
to associate a significant fraction of the red HB clump giants with the same
old and metal-poor population producing the RR Lyraes and the AGB-bump. In this
case, compared to the age-dependent luminosity predictions of stellar evolution
theory, the red HB clump is too bright relative to the RR Lyraes and AGB-bump.
Last, the surface density profile of RR Lyraes is fit by an exponential,
favoring a disk-like rather than spheroidal distribution. We conclude that the
age of the LMC disk is probably similar to the age of the Galactic disk.
(ABRIDGED)

</DOC>
<DOC>
<DOCNO> 39720 </DOCNO>
Observation of coasting beam at the HERA Proton--Ring


  We present data collected with the HERA-B wire target which prove the
existence of coasting beam at the HERA proton storage ring. The coasting beam
is inherently produced by the proton machine operation and is not dominated by
target effects.

</DOC>
<DOC>
<DOCNO> 122109 </DOCNO>
The detection of spiral arm modulation in the mass distribution of an


  Spiral arm modulation in NGC 4062 (an optical flocculent) is detected for the
first time; the Fourier spectra of NGC 4062 and NGC 5248 (a classic grand
design in optical images) are almost identical.

</DOC>
<DOC>
<DOCNO> 100255 </DOCNO>
A[Sl_q(2)] at roots of unity is a free module over A[Sl(2)]


  It is shown that when q is a primitive root of unity of order not equal to 2
mod 4, A(SL_q(2)) is a free module of finite rank over the coordinate ring of
the classical group SL(2). An explicit set of generators is provided.

</DOC>
<DOC>
<DOCNO> 170771 </DOCNO>
Time evolution and squeezing of the field amplitude in cavity QED


  We present the conditional time evolution of the electromagnetic field
produced by a cavity QED system in the strongly coupled regime. We obtain the
conditional evolution through a wave-particle correlation function that
measures the time evolution of the field after the detection of a photon. A
connection exists between this correlation function and the spectrum of
squeezing which permits the study of squeezed states in the time domain. We
calculate the spectrum of squeezing from the master equation for the reduced
density matrix using both the quantum regression theorem and quantum
trajectories. Our calculations not only show that spontaneous emission degrades
the squeezing signal, but they also point to the dynamical processes that cause
this degradation.

</DOC>
<DOC>
<DOCNO> 122067 </DOCNO>
On the Mass and Inclination of the PSR J2019+2425 Binary System


  We report on nine years of timing observations of PSR J2019+2425, a
millisecond pulsar in a wide 76.5 day orbit with a white dwarf. We measure a
significant change over time of the projected semi-major axis of the orbit,
x-dot/x=(1.3+-0.2)x10^-15 s^-1, where x=(a sin i)/c. We attribute this to the
proper motion of the binary. This constrains the inclination angle to i<72
degrees, with a median likelihood value of 63 degrees. A similar limit on
inclination angle arises from the lack of a detectable Shapiro delay signal.
These limits on inclination angle, combined with a model of the evolution of
the system, imply that the neutron star mass is at most 1.51 solar masses; the
median likelihood value is 1.33 solar masses. In addition to these timing
results, we present a polarization profile of this source. Fits of the linear
polarization position angle to the rotating vector model indicate the magnetic
axis is close to alignment with the rotation axis, alpha<30 degrees.

</DOC>
<DOC>
<DOCNO> 11223 </DOCNO>
Detecting Gapless Excitations above Ferromagnetic Domain Walls


  In a two or three dimensional ferromagnetic XXZ model, a low energy
excitation mode above a magnetic domain wall is gapless, whereas all of the
usual spin wave excitations moving around the whole crystal are gapful.
Although this surprising fact was already proved in a mathematically rigorous
manner, the gapless excitations have not yet been detected experimentally. For
this issue, we show theoretically that the gapless excitations appear as the
dynamical fluctuations of the experimental observable, magnetoresistance, in a
ferromagnetic wire. We also discuss other methods (e.g., ferromagnetic
resonance and neutron scattering) to detect the gapless excitations
experimentally.

</DOC>
<DOC>
<DOCNO> 119049 </DOCNO>
The Gravitational Lensing in Redshift-space Correlation Functions of


  The gravitational lensing, as well as the velocity field and the cosmological
light-cone warp, changes the observed correlation function of high-redshift
objects. We present an analytical expression of 3D correlation function,
simultaneously including those three effects. When two objects are separated
over several hundreds Mpc along a line of sight, the observed correlation
function is dominated by the effect of gravitational lensing rather than the
intrinsic clustering. For a canonical lambda-CDM model, the lensing signals in
the galaxy-galaxy and galaxy-QSO correlations are beyond noise levels in
large-scale redshift surveys like the Sloan Digital Sky Survey.

</DOC>
<DOC>
<DOCNO> 84921 </DOCNO>
Black-hole radiation, the fundamental area unit, and the spectrum of


  Bekenstein and Mukhanov have put forward the idea that, in a quantum theory
of gravity a black hole should have a discrete mass spectrum with a concomitant
{\it discrete} line emission. We note that a direct consequence of this
intriguing prediction is that, compared with blackbody radiation, black-hole
radiance is {\it less} entropic. We calculate the ratio of entropy emission
rate from a quantum black hole to the rate of black-hole entropy decrease, a
quantity which, according to the generalized second law (GSL) of
thermodynamics, should be larger than unity. Implications of our results for
the GSL, for the value of the fundamental area unit in quantum gravity, and for
the spectrum of massless particles in nature are discussed.

</DOC>
<DOC>
<DOCNO> 119151 </DOCNO>
Direct Detection of Giant Close-In Planets Around the Source Stars of


  We propose a direct method to detect close-in giant planets orbiting stars in
the Galactic bulge. This method uses caustic-crossing binary microlensing
events discovered by survey teams monitoring the bulge to measure light from a
planet orbiting the source star. When the planet crosses the caustic, it is
more magnified than the source star; its light is magnified by two orders of
magnitude for Jupiter size planets. If the planet is a giant close to the star,
it may be bright enough to make a significant deviation in the light curve of
the star. Detection of this deviation requires intensive monitoring of the
microlensing light curve using a 10-meter class telescope for a few hours after
the caustic. This is the only method yet proposed to directly detect close-in
planets around stars outside the solar neighborhood.

</DOC>
<DOC>
<DOCNO> 99818 </DOCNO>
Planar Dirac Electron in Coulomb and Magnetic Fields


  The Dirac equation for an electron in two spatial dimensions in the Coulomb
and homogeneous magnetic fields is discussed. For weak magnetic fields, the
approximate energy values are obtained by semiclassical method. In the case
with strong magnetic fields, we present the exact recursion relations that
determine the coefficients of the series expansion of wave functions, the
possible energies and the magnetic fields. It is found that analytic solutions
are possible for a denumerably infinite set of magnetic field strengths. This
system thus furnishes an example of the so-called quasi-exactly solvable
models. A distinctive feature in the Dirac case is that, depending on the
strength of the Coulomb field, not all total angular momentum quantum number
allow exact solutions with wavefunctions in reasonable polynomial forms.
Solutions in the nonrelativistic limit with both attractive and repulsive
Coulomb fields are briefly discussed by means of the method of factorization.

</DOC>
<DOC>
<DOCNO> 100321 </DOCNO>
Embeddings of $\ell_p$ into non-commutative spaces


  Let $\M$ be a semi-finite von Neumann algebra equipped with a faithful normal
trace $\tau$. We study the subspace structures of non-commutative Lorentz
spaces $L_{p,q}(\M, \tau)$, extending results of Carothers and Dilworth to the
non-commutative settings. In particular, we show that, under natural conditions
on indices, $\ell_p$ can not be embedded into $L_{p,q}(\M, \tau)$. As
applications, we prove that for $0<p<\infty$ with $p \neq 2$ then $\ell_p$
cannot be strongly embedded into $L_p(\M,\tau)$. Thus providing a
non-commutative extension of a result of Kalton for $0<p<1$ and a result of
Rosenthal for $1\leq p <2$ on $L_p[0,1]$.

</DOC>
<DOC>
<DOCNO> 100095 </DOCNO>
S\'eries Gevrey de type arithm\'etique, I. Th\'eor\`emes de puret\'e et


  Gevrey series are ubiquitous in analysis; any series satisfying some
(possibly non-linear) analytic differential equation is Gevrey of some
rational order. The present work stems from two observations: 1) the classical
Gevrey series, e.g. generalized hypergeometric series with rational
parameters, enjoy arithmetic counterparts of the Archimedean Gevrey condition;
2) the differential operators which occur in classical treatises on special
functions have a rather simple structure: they are either Fuchsian, or have
only two singularities, 0 and infinity, one of them regular, the other
irregular with a single slope...
  The main idea of the paper is that the arithmetic property 1) accounts for
the global analytic property 2): the existence of an injective arithmetic
Gevrey solution at one point determines to a large extent the global behaviour
of a differential operator with polynomial coefficients.
  Proofs use both p-adic and complex analysis, and a detailed arithmetic study
of the Laplace transform.

</DOC>
<DOC>
<DOCNO> 169682 </DOCNO>
Experimental Test of Relativistic Quantum State Collapse with Moving


  An experimental test of relativistic wave-packet collapse is presented. The
tested model assumes that the collapse takes place in the reference frame
determined by the massive measuring detectors. Entangled photons are measured
at 10 km distance within a time interval of less than 5 ps. The two apparatuses
are in relative motion so that both detectors, each in its own inertial
reference frame, are first to perform the measurement. The data always
reproduces the quantum correlations and thus rule out a class of collapse
models. The results also set a lower bound on the "speed of quantum
information" to 0.66 x 10^7 and 1.5 x 10^4 times the speed of light in the
Geneva and the background radiation reference frames, respectively. The very
difficult and deep question of where the collapse takes place - if it takes
place at all - is considered in a concrete experimental context.

</DOC>
<DOC>
<DOCNO> 13615 </DOCNO>
Kondo physics in carbon nanotubes


  The connection of electrical leads to wire-like molecules is a logical step
in the development of molecular electronics, but also allows studies of
fundamental physics. For example, metallic carbon nanotubes are quantum wires
that have been found to act as one-dimensional quantum dots, Luttinger-liquids,
proximity-induced superconductors and ballistic and diffusive one-dimensional
metals. Here we report that electrically-contacted single-wall nanotubes can
serve as powerful probes of Kondo physics, demonstrating the universality of
the Kondo effect. Arising in the prototypical case from the interaction between
a localized impurity magnetic moment and delocalized electrons in a metallic
host, the Kondo effect has been used to explain enhanced low-temperature
scattering from magnetic impurities in metals, and also occurs in transport
through semiconductor quantum dots. The far higher tunability of dots (in our
case, nanotubes) compared with atomic impurities renders new classes of
Kondo-like effects accessible. Our nanotube devices differ from previous
systems in which Kondo effects have been observed, in that they are
one-dimensional quantum dots with three-dimensional metal (gold) reservoirs.
This allows us to observe Kondo resonances for very large electron number (N)
in the dot, and approaching the unitary limit (where the transmission reaches
its maximum possible value). Moreover, we detect a previously unobserved Kondo
effect, occurring for even values of N in a magnetic field.

</DOC>
<DOC>
<DOCNO> 40505 </DOCNO>
First Neutrino Observations from the Sudbury Neutrino Observatory


  The first neutrino observations from the Sudbury Neutrino Observatory are
presented from preliminary analyses. Based on energy, direction and location,
the data in the region of interest appear to be dominated by 8B solar
neutrinos, detected by the charged current reaction on deuterium and elastic
scattering from electrons, with very little background. Measurements of
radioactive backgrounds indicate that the measurement of all active neutrino
types via the neutral current reaction on deuterium will be possible with small
systematic uncertainties. Quantitative results for the fluxes observed with
these reactions will be provided when further calibrations have been completed.

</DOC>
<DOC>
<DOCNO> 11698 </DOCNO>
Quantum tetrahedral mean field theory of the magnetic susceptibility for


  A quantum mean field theory of the pyrochlore lattice is presented. The
starting point is not the individual magnetic ions, as in the usual Curie-Weiss
mean field theory, but a set of interacting corner sharing tetrahedra. We check
the consistency of the model against magnetic susceptibility data, and find a
good agreement between the theoretical predictions and the experimental data.
Implications of the model and future extensions are also discussed.

</DOC>
<DOC>
<DOCNO> 72156 </DOCNO>
Gravitational Interaction of Neutrinos in Models with Large Extra


  We show that in the framework of large extra-dimension models, oscillations
between neutrinos on the brane and those in the bulk can be affected by the
un-suppressed gravitational interaction. For solar neutrinos, oscillation to
sterile states is substantially modified if the size of the extra dimension is
of the order of current bounds and the fundamental scale is near the
electroweak one. The physics of ultra-high energy neutrinos in cosmic-ray
physics is modified even for much larger fundamental scales. These examples are
instances of a more general property of fields allowed to propagate in
different portions of space-time, for which the four dimensional theory
exhibits an effective violation of the principle of equivalence.

</DOC>
<DOC>
<DOCNO> 151264 </DOCNO>
Confining strings, Wilson loops and extra dimensions


  We study solutions of the one-loop beta-functions of the critical bosonic
string theory in the framework of the Renormalization Group (RG) approach to
string theory, considering explicitly the effects of the 21 extra dimensions.
In the RG approach the 26-dimensional manifold is given in terms of a four
dimensional Minkowski spacetime times R and a 21-dimensional hyper-plane. In
calculating the Wilson loops, as it is wellknown for this kind of confining
geometry, two phenomena appear: confinement and over-confinement. There is a
critical minimal surface below of which it leads to confinement only. The role
of the extra dimensions is understood in terms of a dimensionless scale l
provided by them. Therefore the effective string tension in the area law, the
length of the Wilson loops, as well as, the size of the critical minimal
surface depend on this scale. When this confining geometry is used to study a
field-theory beta-function with an infrared attractive point (as the
Novikov-Shifman-Vainshtein-Zakharov beta-function) the range of the couplings
where the field theory is confining depends on that scale. We have explicitly
calculated the l-dependence of that range.

</DOC>
<DOC>
<DOCNO> 102560 </DOCNO>
Higher Nimbers in pawn endgames on large chessboards


  We answer a question posed in [Elkies 1996] (math.CO/9905198) by constructing
a class of pawn endgames on m-by-n boards that show the Nimbers *k for large k.
We do this by modifying and generalizing T.R. Dawson's ``pawns game''
[Berlekamp et al. 1982] (Winning Ways I). Our construction works for m>8 and n
sufficiently large; on the basis of computational evidence we conjecture, but
cannot yet prove, that the construction yields *k for all integers k.

</DOC>
<DOC>
<DOCNO> 71541 </DOCNO>
CP violation and target-space modular invariance


  We show that, in perturbative string models where the source of CP violation
is a complex vacuum expectation value (v.e.v.) for one or more compactification
moduli, CP is conserved if a CP transformation acting on the modulus values is
an element of a target-space (self-)duality group. Where the duality group is
SL(2,Z) the result confirms a conjecture of Bailin et al. that CP is conserved
for v.e.v.'s of the T modulus on the boundary of the fundamental domain, and
generalises Giedt's result on the removability of complex Yukawa couplings in
such models. Our result applies to any model of spontaneous CP violation where
the CP-odd scalar transforms under a symmetry that is not explicitly broken. We
consider whether similar results could be obtained in ``brane worlds''.

</DOC>
<DOC>
<DOCNO> 120826 </DOCNO>
A Photometric Study of the Ages and Metallicities of Early-type Galaxies


  We present deep optical and near-infrared imaging of the rich cluster A2218
at z=0.17. Our optical imaging comes from new multicolour Hubble Space
Telescope WFPC2 observations in the F450W (B), F606W (V) and F814W (I)
passbands. These observations are complemented by deep near-infrared, Ks-band,
imaging from the new INGRID imager on the 4.2-m William Herschel Telescope.
This combination provides unique high-precision multicolour optical-infrared
photometry and morphological information for a large sample of galaxies in the
core of this rich cluster at a lookback time of ~3Gyrs. We analyse the (B-I),
(V-I) and (I-Ks) colours of galaxies spanning a range of a factor of 100 in
K-band luminosity in this region and compare these with grids of stellar
population models. We find that the locus of the colours of the stellar
populations in the luminous (>0.5L*) early-type galaxies, both ellipticals and
S0s, traces a sequence of varying metallicity at a single age. At fainter
luminosities (<0.1L*), this sequence is extended to lower metallicities by the
morphologically-classified ellipticals. However, the faintest S0s exhibit very
different behaviour, showing a wide range in colours, including a large
fraction (30%) with relatively blue colours which appear to have younger
luminosity-weighted ages for their stellar populations, 2-5Gyrs. We show that
the proportion of these young S0s in the cluster population is consistent with
the observed decrease in the S0 population seen in distant clusters when
interpreted within the framework of a two-step spectroscopic and morphological
transformation of accreted spiral field galaxies into cluster S0s.

</DOC>
<DOC>
<DOCNO> 7799 </DOCNO>
Nonintegrability, Chaos, and Complexity


  Two-dimensional driven dissipative flows are generally integrable via a
conservation law that is singular at equilibria. Nonintegrable dynamical
systems are confined to n*3 dimensions. Even driven-dissipative deterministic
dynamical systems that are critical, chaotic or complex have n-1 local
time-independent conservation laws that can be used to simplify the geometric
picture of the flow over as many consecutive time intervals as one likes. Those
conserevation laws generally have either branch cuts, phase singularities, or
both. The consequence of the existence of singular conservation laws for
experimental data analysis, and also for the search for scale-invariant
critical states via uncontrolled approximations in deterministic dynamical
systems, is discussed. Finally, the expectation of ubiquity of scaling laws and
universality classes in dynamics is contrasted with the possibility that the
most interesting dynamics in nature may be nonscaling, nonuniversal, and to
some degree computationally complex.

</DOC>
<DOC>
<DOCNO> 71520 </DOCNO>
The tensor reduction and master integrals of the two-loop massless


  We briefly discuss an algorithm for the tensor reduction of the two-loop
massless crossed boxes, with light-like external legs, and the computation of
the relative master integrals.

</DOC>
<DOC>
<DOCNO> 13372 </DOCNO>
Three-helix-bundle Protein in a Ramachandran Model


  We study the thermodynamic behavior of a model protein with 54 amino acids
that forms a three-helix bundle in its native state. The model contains three
types of amino acids and five to six atoms per amino acid and has the
Ramachandran torsional angles $\phi_i$, $\psi_i$ as its degrees of freedom. The
force field is based on hydrogen bonds and effective hydrophobicity forces. For
a suitable choice of the relative strength of these interactions, we find that
the three-helix-bundle protein undergoes an abrupt folding transition from an
expanded state to the native state. Also shown is that the corresponding one-
and two-helix segments are less stable than the three-helix sequence. 

</DOC>
<DOC>
<DOCNO> 101150 </DOCNO>
On The Homflypt Skein Module of S^1 x S^2


  Let $k$ be a subring of the field of rational functions in $x, v, s$ which
contains $x^{\pm 1}, v^{\pm 1}, s^{\pm 1}$. If $M$ is an oriented 3-manifold,
let $S(M)$ denote the Homflypt skein module of $M$ over $k$. This is the free
$k$-module generated by isotopy classes of framed oriented links in $M$
quotiented by the Homflypt skein relations: (1)
$x^{-1}L_{+}-xL_{-}=(s-s^{-1})L_{0}$; (2) $L$ with a positive twist
$=(xv^{-1})L$; (3) $L\sqcup O=(\frac{v-v^{-1}}{s-s^{-1}})L$ where $O$ is the
unknot. We give two bases for the relative Homflypt skein module of the solid
torus with 2 points in the boundary. The first basis is related to the basis of
$S(S^1\times D^2)$ given by V. Turaev and also J. Hoste and M. Kidwell; the
second basis is related to a Young idempotent basis for $S(S^1\times D^2)$
based on the work of A. Aiston, H. Morton and C. Blanchet. We prove that if the
elements $s^{2n}-1$, for $n$ a nonzero integer, and the elements
$s^{2m}-v^{2}$, for any integer $m$, are invertible in $k$, then $S(S^{1}
\times S^2)=k$-torsion module $\oplus k$. Here the free part is generated by
the empty link $\phi$. In addition, if the elements $s^{2m}-v^{4}$, for $m$ an
integer, are invertible in $k$, then $S(S^{1} \times S^2)$ has no torsion. We
also obtain some results for more general $k$.

</DOC>
<DOC>
<DOCNO> 150408 </DOCNO>
Noncommutative Open String: Neutral and Charged


  We review the quantization of open string in NS-NS background and demonstrate
that its endpoint becomes noncommutative. The same approach allows us to
determine the noncommutativity that arises for a charged open string in
background gauge fields. While NS-NS background is relevant for ``worldvolume''
noncommutativity, a simple argument suggests that RR background is likely to be
relevant for ``spacetime'' noncommutativity.

</DOC>
<DOC>
<DOCNO> 69342 </DOCNO>
Width and Partial Widths of Unstable Particles


  In the gauge theory context, a definition of branching ratios and partial
widths of unstable particles is proposed that satisfies the basic principles of
additivity and gauge independence. A simpler definition, similar to the
conventional one, is examined in the Z^0-boson case. In order to establish
contact with experiment, we show that it leads to a peak cross section that
justifies the expression used by the LEP Electroweak Working Group through
next-to-next-to-leading order, provided that the pole rather than the on-shell
mass and width of the Z^0 boson are employed.

</DOC>
<DOC>
<DOCNO> 11398 </DOCNO>
Two-loop beta-function from the exact renormalization group


  We calculate the two-loop renormalization group (RG) beta-function of a
massless scalar field theory from the irreducible version of Polchinski's exact
RG flow equation. To obtain the correct two-loop result within this method, it
is necessary to take the full momentum-dependence of the irreducible four-point
vertex and the six-point vertex into account. Although the same calculation
within the orthodox field theory method is less tedious, the flow equation
method makes no assumptions about the renormalizability of the theory, and
promises to be useful for performing two-loop calculations for
non-renormalizable condensed-matter systems. We pay particular attention to the
problem of the field rescaling and the effect of the associated exponent eta on
the RG flow.

</DOC>
<DOC>
<DOCNO> 71175 </DOCNO>
Twist-3 contribution to the $\gamma^*\gamma\to \pi\pi$ amplitude in the


  We have calculated the Wandzura-Wilczek contribution to the twist-3 part of
$\gamma^*\gamma\to 2\pi$ amplitude. It describes interaction of the
longitudinally polarized virtual photon with the real one, and it is suppressed
by 1/Q, where $Q^2$ is the virtuality of the $\gamma^*$, as compared to the
twist-2 contribution. We have found that, in the Wandzura-Wilczek
approximation, factorization applies to the twist-3 amplitude.

</DOC>
<DOC>
<DOCNO> 118887 </DOCNO>
J-Net Galactic Plane Survey of VLBI Radio Sources for VLBI Exploration


  In order to search for new VLBI sources in the Galactic plane that can be
used as phase reference sources in differential VLBI, we have conducted 22 GHz
observations of radio sources in the Galactic plane using the Japanese VLBI
Network (J-Net). We have observed 267 VLBI source candidates selected from
existing radio surveys and have detected 93 sources at the signal-to-noise
ratio larger than 5. While 42 of the 93 detected sources had already been
detected with VLBI at relatively lower frequency (typically 2 to 8 GHz), the
remaining 51 are found to be new VLBI sources detected for the first time.
These VLBI sources are located within $|b|\le 5^\circ$, and have a large number
of Galactic maser sources around them. Thus, they are potential candidates for
phase reference sources for VLBI Exploration of Radio Astrometry (VERA), which
is the first VLBI array dedicated to the phase referencing VLBI astrometry
aiming at measuring the parallax and proper motion of maser sources in the
whole Galaxy.

</DOC>
<DOC>
<DOCNO> 84611 </DOCNO>
Gaussian superpositions in scalar-tensor quantum cosmological models


  A free scalar field minimally coupled to gravity model is quantized and the
Wheeler-DeWitt equation in minisuperspace is solved analytically, exhibiting
positive and negative frequency modes. The analysis is performed for positive,
negative and zero values of the curvature of the spatial section. Gaussian
superpositions of the modes are constructed, and the quantum bohmian
trajectories are determined in the framework of the Bohm-de Broglie
interpretation of quantum cosmology. Oscillating universes appear in all cases,
but with a characteristic scale of the order of the Planck scale. Bouncing
regular solutions emerge for the flat curvature case. They contract classically
from infinity until a minimum size, where quantum effects become important
acting as repulsive forces avoiding the singularity and creating an
inflationary phase, expanding afterwards to an infinite size, approaching the
classical expansion as long as the scale factor increases. These are
non-singular solutions which are viable models to describe the early Universe.

</DOC>
<DOC>
<DOCNO> 13458 </DOCNO>
Universality of the Directed Polymer Model


  The universality of the directed polymer model and the analogous
 KPZ equation is supported by numerical simulations using non-Gaussian random
probability distributions in two, three and four dimensions.
 It is shown that although in the non-Gaussian cases the \emph{finite size}
estimates of the energy exponents are below the persumed universal values,
these estimates \emph{increase} with the system size, and the further they are
below the universal values, the higher is their rate of increase. The results
are explained in terms of the efficiency of variance reduction during the
optimization process.

</DOC>
<DOC>
<DOCNO> 8330 </DOCNO>
Elasticity of thin rods with spontaneous curvature and torsion - beyond


  We study three-dimensional deformations of thin inextensible elastic rods
with non-vanishing spontaneous curvature and torsion. In addition to the usual
description in terms of curvature and torsion which considers only the
configuration of the centerline of the rod, we allow deformations that involve
the rotation of the rod's cross-section around its centerline. We derive new
expressions for the mechanical energy and for the force and moment balance
conditions for the equilibrium of a rod under the action of arbitrary external
loads. Several illustrative examples are studied and the connection between our
results and recent experiments on stretching of supercoiled DNA molecules is
discussed.

</DOC>
<DOC>
<DOCNO> 100022 </DOCNO>
Matrix Representations of Octonions and Their Applications


  As is well-known, the real quaternion division algebra $ {\cal H}$ is
algebraically isomorphic to a 4-by-4 real matrix algebra. But the real division
octonion algebra ${\cal O}$ can not be algebraically isomorphic to any matrix
algebras over the real number field ${\cal R}$, because ${\cal O}$ is a
non-associative algebra over ${\cal R}$. However since ${\cal O}$ is an
extension of ${\cal H}$ by the Cayley-Dickson process and is also
finite-dimensional, some pseudo real matrix representations of octonions can
still be introduced through real matrix representations of quaternions. In this
paper we give a complete investigation to real matrix representations of
octonions, and consider their various applications to octonions as well as
matrices of octonions.

</DOC>
<DOC>
<DOCNO> 69071 </DOCNO>
Recent Results from (Full) Lattice QCD


  An overview of the Lattice technique for studies of the strong interaction is
given. Recent results from the UKQCD lattice collaboration are presented. These
concentrate on spectral quantities calculated using full (i.e. unquenched) QCD.
A comparison with quenched results is made. Novel methods of extracting
spectral properties from two-point functions are described.

</DOC>
<DOC>
<DOCNO> 10797 </DOCNO>
Fermi-Edge Singularities in AlxGa1-xAs Quantum Wells : Extrinsic Versus


  A Fano resonance mechanism is evidenced to control the formation of optical
Fermi-edge singularities in multi-subband systems such as remotely doped
AlxGa1-xAs heterostructures. Using Fano parameters, we probe the physical
nature of the interaction between Fermi-sea electrons and empty conduction
subbands. We show that processes of extrinsic origin like alloy-disorder
prevail easily at 2D over multiple diffusions from charged valence holes
expected by many-body scenarios.

</DOC>
<DOC>
<DOCNO> 178451 </DOCNO>
Quantum Monte Carlo calculations of A=8 nuclei


  We report quantum Monte Carlo calculations of ground and low-lying excited
states for A=8 nuclei using a realistic Hamiltonian containing the Argonne v18
two-nucleon and Urbana IX three-nucleon potentials. The calculations begin with
correlated eight-body wave functions that have a filled alpha-like core and
four p-shell nucleons LS-coupled to the appropriate (J+/-;T) quantum numbers
for the state of interest. After optimization, these variational wave functions
are used as input to a Green's function Monte Carlo calculation made with a new
constrained path algorithm. We find that the Hamiltonian produces an 8Be ground
state that is within 2 MeV of the experimental resonance, but the other
eight-body energies are progressively worse as the neutron-proton asymmetry
increases. The 8Li ground state is stable against breakup into subclusters, but
the 8He ground state is not. The excited state spectra are in fair agreement
with experiment, with both the single-particle behavior of 8He and 8Li and the
collective rotational behavior of 8Be being reproduced. We also examine energy
differences in the T=1 and 2 isomultiplets and isospin-mixing matrix elements
in the excited states of 8Be. Finally, we present densities, momentum
distributions, and studies of the intrinsic shapes of these nuclei, with 8Be
exhibiting a definite 2-alpha cluster structure.

</DOC>
<DOC>
<DOCNO> 117856 </DOCNO>
Wide Field CCD Surface Photometry of the Giant Elliptical Galaxy NGC


  We present deep wide field (16'.4 x 16'.4) Washington CT1 CCD surface
photometry of the giant elliptical galaxy NGC 4472, the brightest member in the
Virgo cluster. Our data cover a wider field than any previous CCD photometry as
well as going deeper. Surface brightness profiles of NGC 4472 are not well fit
by a single King model, but they can be fit approximately by two King models:
with separate models for the inner and outer regions. Surface brightness
profiles for the outer region can also be fit approximately by a deVaucouleurs
law. There is clearly a negative color gradient within 3' of NGC 4472, in the
sense that the color gets bluer with increasing radius. The slope of the color
gradient for this region is derived to be $\Delta \mu (C-T_1)$ = -0.08 mag
arcsec$^{-2}$ for $\Delta \log r =1$, which corresponds to a metallicity
gradient of $\Delta$ [Fe/H] $= -0.2$ dex. However, the surface color gets
redder slowly with increasing radius beyond 3'. A comparison of the structural
parameters of NGC 4472 in C and T1 images has shown that there is little
difference in the ellipse shapes between isochromes and isophotes. In addition,
photometric and structural parameters of NGC 4472 have been determined.

</DOC>
<DOC>
<DOCNO> 70408 </DOCNO>
Latest cosmological constraints on the densities of hot and cold dark


  As experimentalists step up their pursuit of cold dark matter particles and
neutrino masses, cosmological constraints are tightening. We compute the joint
constraints on 11 cosmological parameters from cosmic microwave background and
large scale structure data, and find that at 95% confidence, the total
(cold+hot) dark matter density is h^2 Omega_dark = 0.20 +.12 -.10 with at most
38% of it being hot (due to neutrinos). A few assumptions, including negligible
neutrinos, tighten this measurement to h^2 Omega_dark = 0.13 +0.04 -0.02, i.e,
2.4e-27 kg/m^3 give or take 20%.

</DOC>
<DOC>
<DOCNO> 151450 </DOCNO>
A Noncommutative Version of the Nonlinear Schrodinger Equation


  We apply a (Moyal) deformation quantization to a bicomplex associated with
the classical nonlinear Schrodinger equation. This induces a deformation of the
latter equation to noncommutative space-time while preserving the existence of
an infinite set of conserved quantities.

</DOC>
<DOC>
<DOCNO> 69456 </DOCNO>
A Predictive Minimal Model for Neutrino Masses and Mixings


  A model is considered in which the scale of the heavy singlet neutrinos is a
few orders of magnitude below the grand unification scale and where
right-handed vector bosons play still a negligible role. In a basis with
diagonal up-quark and Dirac-neutrino mass matrices it is assumed that the heavy
neutrino mass matrix has only zero elements in its diagonal, in analogy to the
light neutrino mass matrix in the Zee model. Connecting then the remaining
matrix elements with the small parameter describing the hierarchy of quark
masses and mixings and by assuming commutativity of the charged lepton with the
down-quark mass matrix, the calculation of all neutrino properties can be
performed in terms of the two mass differences relevant for atmospheric and
solar neutrino oscillations. CP-violation is directly related to CP-violation
in the quark sector.

</DOC>
<DOC>
<DOCNO> 8149 </DOCNO>
Universality in Quantum Hall Systems: Coset Construction of


  Incompressible Quantum Hall fluids (QHF's) can be described in the scaling
limit by three-dimensional topological field theories. Thanks to the
correspondence between three-dimensional topological field theories and two
dimensional chiral conformal field theories (CCFT's), we propose to study QHF's
from the point of view of CCFT's.
  We derive consistency conditions and stability criteria for those CCFT's that
can be expected to describe a QHF. A general algorithm is presented which uses
simple currents to construct interesting examples of such CCFT's. It
generalizes the description of QHF's in terms of Quantum Hall lattices.
Explicit examples, based on the coset construction, provide candidates for the
description of Quantum Hall fluids with Hall conductivity s_H=1/2 e^2/h, 1/4
e^2/h, 3/5 e^2/h, e^2/h,...

</DOC>
<DOC>
<DOCNO> 84718 </DOCNO>
Null surfaces formulation in 3D


  The Null Surface Formulation of General Relativity is developed for 2+1
dimensional gravity. The geometrical meaning of the metricity condition is
analyzed and two approaches to the derivation of the field equations are
presented. One method makes explicit use of the conformal factor while the
other only uses conformal information. The resulting set of equations contain
the same geometrical meaning as the 4-D formulation without the technical
complexities of the higher dimensional analog. A canonical family of null
surfaces in this formulation, the light cone cuts of null infinity, are
constructed on asymptotically flat space times and some of their kinematical
aspects discussed. A particular example, which nevertheless contains most of
the generic features is explicitly constructed and analyzed, revealing the
behavior predicted in the full theory.

</DOC>
<DOC>
<DOCNO> 121889 </DOCNO>
LMC and SMC Cepheids: combining OGLE with DENIS 2MASS infrared data


  (Abridged) I cross-correlate the OGLE database of Cepheids in the Large and
Small Magellanic Clouds (MCs) with the second incremental release of the 2MASS
JHK survey, and the DENIS IJK point source catalog towards the MCs.
  Of the 3384 Cepheids in OGLE in both Clouds, 1745 have a counterpart in the
2MASS survey within an 1" radius and good-photometry in all three bands. Only
173 have a counterpart in the DENIS survey within an 1" radius and
good-photometry in all three bands. The reason for this difference is that the
limiting magnitudes of the 2MASS survey are considerably fainter than for
DENIS.
  To describe to first order the geometrical configuration of the MCs a plane
is fitted to the reddening-free Wesenheit (W) index. For the LMC an inclination
angle of 18 $\pm$ 3\degr is derived, for the SMC a value of $i = 68 \pm 2$\degr
is derived. These results are being used to take out the effect that some
Cepheids are closer to the observer than others.
  Using single-epoch 2MASS data for the OGLE Cepheids, PL-relations are fitted
in JHK for both Fundamental mode (FU) and First-overtone (FO) pulsators, taking
out the effect of the inclined disk.
  The derived PL-relations are used to derive a relative distance modulus of
0.50 \pm 0.02 between SMC and LMC assuming no metallicity correction.
  Combining the zero points of the Galactic and MCs PL-relations distance
moduli of 18.60 $\pm$ 0.11 (based on W) and 18.55 $\pm$ 0.17 (based on K) to
the LMC, and of 19.11 $\pm$ 0.11 (W) and 19.04 $\pm$ 0.17 (K) to the SMC are
derived (without taking into account possible metallicity corrections).

</DOC>
<DOC>
<DOCNO> 101915 </DOCNO>
On blockers in bounded posets


  This paper has been withdrawn by the author.

</DOC>
<DOC>
<DOCNO> 99713 </DOCNO>
On higher order analogues of de Rham cohomology


  If K is a commutative ring and A is a K-algebra, for any sequence $\sigma $
of positive integers there exists an higher order analogue dR($\sigma $) of the
standard de Rham complex dR(1,...,1,...), which can also be defined starting
from suitable ("differentially closed") subcategories of (A-mod). The main
result of this paper is that the cohomology of dR($\sigma $) does not depend on
$\sigma $, under some smoothness assumptions on the ambient category. Before
proving the main theorem we give a rather detailed exposition of all relevant
(to our present purposes) functors of differential calculus on commutative
algebras. This part can be also of an independent interest.

</DOC>
<DOC>
<DOCNO> 116597 </DOCNO>
Universality and individuality in a neural code


  The problem of neural coding is to understand how sequences of action
potentials (spikes) are related to sensory stimuli, motor outputs, or
(ultimately) thoughts and intentions. One clear question is whether the same
coding rules are used by different neurons, or by corresponding neurons in
different individuals. We present a quantitative formulation of this problem
using ideas from information theory, and apply this approach to the analysis of
experiments in the fly visual system. We find significant individual
differences in the structure of the code, particularly in the way that temporal
patterns of spikes are used to convey information beyond that available from
variations in spike rate. On the other hand, all the flies in our ensemble
exhibit a high coding efficiency, so that every spike carries the same amount
of information in all the individuals. Thus the neural code has a quantifiable
mixture of individuality and universality.

</DOC>
<DOC>
<DOCNO> 68667 </DOCNO>
e^+ e^- --> {tilde t}_1 {tilde t}_1^* (H_1) in the MSSM with explicit CP


  The author considers the effects of the CP-violating phases, e. g. arg(A_t)
and arg(mu) on the e^+ e^- --> {tilde t}_1 {tilde t}_1^* (H_1) processes. The
third generation squark trilinear terms give significant contributions to the
Higgs potential at the one-loop level. This results in the changes of the stop
masses and the lighter stop - the lighter anti-stop - the lightest Higgs
coupling. The author shows the coupling and the loop effects on the processes.
And the author will discuss the determination method of soft parameters.

</DOC>
<DOC>
<DOCNO> 69080 </DOCNO>
Multiple Scattering, Parton Energy Loss and Modified Fragmentation


  Modified quark fragmentation functions in deeply inelastic $eA$ collisions
and their QCD evolution equations are derived for the first time in the
framework of multiple parton scattering. Induced radiation gives rise to
additional terms in the evolution equations and thus softens the modified quark
fragmentation functions. The results in the next-leading-twist depend on both
diagonal and off-diagonal twist-four parton distributions and the combination
of which clearly manifests the LPM interference pattern. The predicted
modification depends quadratically on the nuclear size ($A^{2/3}$).
Generalization to the case of hot QCD medium is also discussed.

</DOC>
<DOC>
<DOCNO> 8568 </DOCNO>
Disturbance spreading in incommensurate and quasiperiodic systems


  The propagation of an initially localized excitation in one dimensional
incommensurate, quasiperiodic and random systems is investigated numerically.
It is discovered that the time evolution of variances $\sigma^2(t)$ of atom
displacements depends on the initial condition. For the initial condition with
nonzero momentum, $\sigma^2(t)$ goes as $t^\alpha$ with $\alpha=1$ and 0 for
incommensurate Frenkel-Kontorova (FK) model at $V$ below and above $V_c$
respectively; and $\alpha=1$ for uniform, quasiperiodic and random chains. It
is also found that $\alpha=1-\beta$ with $\beta$ the exponent of distribution
function of frequency at zero frequency, i.e., $\rho(\omega)\sim
\omega^{\beta}$ (as $\omega\to 0$). For the initial condition with zero
momentum, $\alpha=0$ for all systems studied. The underlying physical meaning
of this diffusive behavior is discussed.

</DOC>
<DOC>
<DOCNO> 118800 </DOCNO>
Discovery of a new pulsating X-ray source with a 1549.1-s period, AX


  A new pulsating X-ray source, AX J183220-0840, with a 1549.1-s period was
discovered at R.A.= 18h32m20s and Dec.=-8d40'30'' (J2000,
uncertainty=0.6degree) during an ASCA observation on the Galactic plane. The
source was observed two times, in 1997 and in 1999. A phase-averaged X-ray flux
of 1.1E-11 ergs cm-2 s-1 and pulsation period of 1549.1+/-0.4 s were
consistently obtained from these two observations. The X-ray spectrum was
represented by a flat absorbed power-law with a photon-index of =~0.8 and an
absorption column density of =~1.3E22 cm-2. Also, a signature of iron K-shell
line emission with a centroid of 6.7 keV and an equivalent width of
approximately 450 eV was detected. From the pulsation period and the iron-line
feature, AX J183220-0840 is likely to be a magnetic white dwarf binary with a
complexly absorbed thermal spectrum with a temperature of about 10 keV.

</DOC>
<DOC>
<DOCNO> 10996 </DOCNO>
Dephasing of Aharonov-Bohm oscillations in a mesoscopic ring with a


  We present a detailed analysis of the Aharonov-Bohm interference oscillations
manifested through transmission of an electron in a mesoscopic ring with a
magnetic impurity atom inserted in one of its arms. The electron interacts with
the impurity through the exchange interaction leading to exchange spin-flip
scattering. Transmission in the spin-flipped and spin-unflipped channels are
explicitly calculated. We show that the spin-flipper acts as a dephasor in
spite of absence of any inelastic scattering. The spin-conductance (related to
spin-polarized transmission coefficient) is asymmetric in the flux reversal as
opposed to the two probe conductance which is symmetric under flux reversal.

</DOC>
<DOC>
<DOCNO> 85122 </DOCNO>
A Time Varying Strong Coupling Constant as a Model of Inflationary


  We consider a scenario where the strong coupling constant was changing in the
early universe. We attribute this change to a variation in the colour charge
within a Bekenstein-like model. Treating the vacuum gluon condensate $<G^2>$ as
a free paramete r, we could generate inflation with the required properties to
solve the fluctuation and other standard cosmology problems. A possible
approach to end the inflation is suggested.

</DOC>
<DOC>
<DOCNO> 69113 </DOCNO>
Shadowing of gluons in perturbative QCD: A comparison of different


  We investigate the different perturbative QCD-based models for nuclear
shadowing of gluons. We show that in the kinematic region appropriate to RHIC
experiment, all models give similar estimates for the magnitude of gluon
shadowing. At scales relevant to LHC, there is a sizable difference between
predictions of the different models.

</DOC>
<DOC>
<DOCNO> 40604 </DOCNO>
Review of experimental results on neutral B meson oscillations


  The current status of the experimental knowledge of neutral B meson
oscillation is reviewed. The B0d oscillation frequency is precisely measured by
SLD, CDF and the LEP experiments. An overview of the analyses and their
combination is presented. Preliminary measurements and perspectives at the
running B factories are also briefly discussed. The much faster B0s
oscillations have not yet been resolved, despite the progress recently by SLD
and ALEPH. The world combination is presented, together with the expected and
observed lower limit on the B0s oscillation frequency. The "amplitude method",
used to combine the analyses in order to set the limits, is discussed also as a
tool to establish the significance of a possible signal.

</DOC>
<DOC>
<DOCNO> 118911 </DOCNO>
The H Beta Index as an Age Indicator of Old Stellar Systems: The Effects


  The strength of the H$\beta$ index has been computed for the integrated
spectra of model globular clusters from the evolutionary population synthesis.
These models take into account, for the first time, the detailed systematic
variation of horizontal-branch (HB) morphology with age and metallicity. Our
models show that the H$\beta$ index is significantly affected by the presence
of blue HB stars. Because of the contribution from blue HB stars, the H$\beta$
does not monotonically decrease as metallicity increases at a given age.
Instead, it reaches a maximum strength when the distribution of HB stars is
centered around 9500 K, the temperature where the H$\beta$ index becomes
strongest. Our models indicate that the strength of the H$\beta$ index
increases as much as 0.75 {\AA} due to the presence of blue HB stars.
  The comparison of the recent Keck observations of the globular cluster system
in the Milky Way Galaxy with those in giant elliptical galaxies, NGC 1399 and
M87, shows a systematic shift in the H$\beta$ against metallicity plane. Our
models suggest that this systematic difference is understood if the globular
cluster systems in giant elliptical galaxies are several billion years older,
in the mean, than the Galactic counterpart. Further observations of globular
cluster systems in the external galaxies from the large ground-based telescopes
and space UV facilities will enable to clarify whether this difference is
indeed due to the age difference or other explanations are also possible.

</DOC>
<DOC>
<DOCNO> 101294 </DOCNO>
Bordism classes of the multiple points manifolds


  Let $f:V^n\looparrowright M^m$ be a smooth generic immersion. Then the set of
points, that have at least $k$ preimages is an image of a (non-generic)
immersion. If the manifolds $V^n$ and $M^m$ are oriented and $m-n$ is even,
then the manifold of $k$-fold points is also oriented. In this paper we compute
the oriented bordism class of the manifold of $k$-fold points in terms of the
differential $df$, provided the tangent bundle of the manifold $M^m$ has a
nowhere zero cross-section.

</DOC>
<DOC>
<DOCNO> 13099 </DOCNO>
Emergence of Classicality in Quantum Phase Transitions


  We show that classicality emerges during quantum phase transitions due to
parametric interactions without coupling to environments. The Wigner functions
are explicitly calculated for the Gaussian vacuum, number, and thermal states
of a free scalar field that describes the spinodal instability regime. The
Wigner functions are sharply peaked around their classical trajectories during
the phase transition and exhibit classical correlation only for unstable long
wavelength modes but retain quantum coherence for short wavelength modes. Thus
classicality emerges from the quantum evolution of phase transitions without a
classical order parameter. We define a quantal ordering parameter that is
linear in the field variable and satisfies the classical field equation.

</DOC>
<DOC>
<DOCNO> 100860 </DOCNO>
On motives for Deligne-Mumford stacks


  We define and compare two different definitions of Chow motives for
Deligne-Mumford stacks, associated with two definitions of Chow rings. The main
result we prove is that both categories of motives are equivalent to the usual
category of motives of algebraic varieties, but the motives of a given stack
associated with both theories are not isomorphic. We will also give some
examples of motives associated with some alegbraic stacks.

</DOC>
<DOC>
<DOCNO> 118206 </DOCNO>
The Lyman Continuum Polarization Rise in the QSO PG 1222+228


  Some QSOs show an abrupt, strong rise in polarization near rest wavelength
750 A. If this arises in the atmosphere of an accretion disk around a
supermassive black hole, it may have diagnostic value. In PG 1222+228, the
polarization rise occurs at the wavelength of a sharp drop in flux. We examine
and reject interpretations of this feature involving a high velocity outflow.
The observations agree with a model involving several intervening Lyman limit
systems, two of which happen to coincide with the Lyman continuum polarization
rise. After correction for the Lyman limit absorption, the continuum shortward
of 912 A is consistent with a typical power-law slope, alpha = -1.8. This
violates the apparent pattern for the Lyman limit polarization rises to occur
only in ``candidate Lyman edge QSOs''. The corrected, polarized flux rises
strongly at the wavelength of the polarization rise, resembling the case of PG
1630+377. The rise in polarized flux places especially stringent requirements
on models.

</DOC>
<DOC>
<DOCNO> 39999 </DOCNO>
BTeV - an Experiment to Measure Mixing, CP Violation, and Rare Decays of


  We discuss the physics goals and rationale for a detector to study Beauty and
Charm decays in the forward direction at the Fermilab Tevatron Collider. We
then describe the BTeV detector which has been designed to achieve these goals
and present its physics reach based on extensive simulation. We conclude by
comparing BTeV to other experiments designed to explore similar topics.

</DOC>
<DOC>
<DOCNO> 12593 </DOCNO>
Competing Interactions among Supramolecular Structures on Surfaces


  A simple model was constructed to describe the polar ordering of
non-centrosymmetric supramolecular aggregates formed by self assembling
triblock rodcoil polymers. The aggregates are modeled as dipoles in a lattice
with an Ising-like penalty associated with reversing the orientation of nearest
neighbor dipoles. The choice of the potentials is based on experimental results
and structural features of the supramolecular objects. For films of finite
thickness, we find a periodic structure along an arbitrary direction
perpendicular to the substrate normal, where the repeat unit is composed of two
equal width domains with dipole up and dipole down configuration. When a short
range interaction between the surface and the dipoles is included the balance
between the up and down dipole domains is broken. Our results suggest that due
to surface effects, films of finite thickness have a none zero macroscopic
polarization, and that the polarization per unit volume appears to be a
function of film thickness.

</DOC>
<DOC>
<DOCNO> 68125 </DOCNO>
Exact Solutions of the Dirac Equation for Modified Coulombic Potentials


  Exact solutions are found to the Dirac equation for a combination of Lorentz
scalar and vector Coulombic potentials with additional non-Coulombic parts. An
appropriate linear combination of Lorentz scalar and vector non-Coulombic
potentials, with the scalar part dominating, can be chosen to give exact
analytic Dirac wave functions. The method works for the ground state or for the
lowest orbital state with l=j-{1/2}, for any j.

</DOC>
<DOC>
<DOCNO> 116581 </DOCNO>
The Precessing Top


  I discuss the precession motion of a symmetrical top without the assumption
that its precessional velocity is much smaller than its spin angular velocity.
I derive the general formula for the precessional velocity in an elementary way
and discuss the cases of slow and fast precessions.

</DOC>
<DOC>
<DOCNO> 68072 </DOCNO>
Higgs Boson Decays to tau-pairs in the s-channel at a Muon Collider


  We study the observability of the $\tautau$ decay mode of a Higgs boson
produced in the $s$-channel at a muon collider. We find that the spin
correlations of the $\tautau$ in $\tau\to \pi\nu_{\tau}, \rho\nu_{\tau}$ decays
are discriminative between the Higgs boson signal and the Standard Model
background. Observation of the predicted distinctive distribution can confirm
the spin-0 nature of the Higgs resonance. The relative coupling strength of the
Higgs boson to $b$ and $\tau$ can also be experimentally determined.

</DOC>
<DOC>
<DOCNO> 12104 </DOCNO>
Proximity to a Nearly Superconducting Quantum Critical Liquid


  The coupling between superconductors and a quantum critical liquid that is
nearly superconducting provides natural interpretation for the Josephson effect
over unexpectedly long junctions, and the remarkable stripe-spacing dependence
of the critical temperature in LSCO and YBCO superconductors.

</DOC>
<DOC>
<DOCNO> 10493 </DOCNO>
CPA density of states and conductivity in a double-exchange system


  We study density of states and conductivity of the doped double-exchange
system, treating interaction of charge carriers both with the localized spins
and with the impurities in the coherent potential approximation. It is shown
that under appropriate conditions there is a gap between the conduction band
and the impurity band in paramagnetic phase, while the density of states is
gapless in ferromagnetic phase. This can explain metal-insulator transition
frequently observed in manganites and magnetic semiconductors. Activated
conductivity in the insulator phase is numerically calculated.

</DOC>
<DOC>
<DOCNO> 121584 </DOCNO>
Multiband optical polarimetry of the BL Lac object PKS 2155--304.


  The polarized and total flux of the BL Lac object PKS 2155-304 were monitored
intensively and simultaneously in the optical UBVRI bands with the Turin
photopolarimeter at the CASLEO 2.15 m telescope during 4 campaigns in June,
August, November 1998 and August 1999. The effective observation time amounted
to ~47 hours. PKS 2155-304 showed a linear polarization percentage (P) usually
ranging between 3% and 7% and a polarization position angle (PA) mainly between
70 and 120 deg. The highest temporal resolution of our observations, 15
minutes, is unprecedented for polarimetric monitoring of this source, and has
allowed us to detect amplitude variations of the linear polarization percentage
from 6 to 7.5% in time scales of hours. In some nights the polarization
percentage seems to increase toward shorter wavelengths, however the polarized
spectrum does not vary significantly with time. The most remarkable variability
event occurred on 1998 June 18, when the degree of linear polarization
decreased by more than a factor 2 in one day in all bands, while the PA rotated
by 90 deg. This is consistent with the presence of two emission components, of
different polarization degree and position angle. Intranight variability of P
and PA can be interpreted with small amplitude physical or geometrical changes
within the jet. Measurements of the circular polarization over time intervals
of days set upper limits of 0.2%. Simultaneous photometry taken with the Turin
Photopolarimeter and with a CCD camera at Cordoba Astronomical Observatory did
not show light variations correlated with those of the linearly polarized flux.

</DOC>
<DOC>
<DOCNO> 10396 </DOCNO>
Two energy gaps in cuprates: pairing and coherence gaps: The


  Tunneling and inelastic neutron scattering (INS) measurements in cuprates are
discussed. There is a clear discrepancy among energy-gap values for different
90 K cuprates, inferred from tunneling measurements. By using the phase diagram
of hole-doped cuprates we interpret tunneling measurements in 90 K cuprates and
INS data in YBCO.

</DOC>
<DOC>
<DOCNO> 13184 </DOCNO>
The Quantum Josephson Hamiltonian In The Phase Representation


  The quantum Josephson Hamiltonian of two weakly linked Bose-Einstein
condensates is written in an overcomplete phase representation, thus avoiding
the problem of defining a Hermitian phase operator. We discuss the limit of
validity of the standard, non-rigorous Mathieu equation, due to the onset of a
higher order $\cos 2 \phi$ term in the Josephson potential, and also to the
overcompleteness of the representation (the phase $\phi$ being the relative
phase between the two condensates). We thereby unify the Boson Hubbard and
Quantum Phase models.

</DOC>
<DOC>
<DOCNO> 178722 </DOCNO>
Mean field studies of high-spin properties in the $A\sim 30$ and 60


  The importance of deformation changes and the possible role of proton-neutron
pairing correlations on the properties of paired band crossings at
superdeformation in the $A\sim 60$ mass region have been analyzed. The present
analysis, supported in part by the cranked relativistic Hartree-Bogoliubov
calculations for the SD band in $^{60}$Zn, suggests that when going from
$^{60}$Zn to neighboring odd nuclei the properties of paired band crossings are
strongly influenced by deformation changes. A number of questions related to
the superdeformation in the $A\sim 30$ mass region has been studied with the
cranked relativistic mean field theory and the configuration-dependent cranked
Nilsson-Strutinsky approach.

</DOC>
<DOC>
<DOCNO> 101200 </DOCNO>
On k-abelian, p-filiform Lie algebras


  We classify the (n-5)-filiform Lie algebras which have the additional
property of a non-abelian derived subalgebra. We show that this property is
strongly related with the structure of the Lie algebra of derivations;
explicitely we show that if a (n-5)-filiform algebra is characteristically
nilpotent, then it must be 2-abelian. We also give applications of k-abelian
Lie algebras to the construction of solvable rigis algebras, as well as to the
theory of nilalgebras of parabolic subalgebras in the example of the
exceptional simple model E_{6}.

</DOC>
<DOC>
<DOCNO> 40501 </DOCNO>
Search for CP violation at CLEO


  Recent results from CLEO on the search for CP violation in beauty and charm
meson decays are reviewed.

</DOC>
<DOC>
<DOCNO> 85486 </DOCNO>
FRW Cosmological Solutions in M-theory


  We present the canonical and quantum cosmological investigation of a
four-dimensional, spatially flat, Friedmann-Robertson-Walker (FRW) model that
is derived from the bosonic Neveu-Schwarz/Neveu-Schwarz sector of the
low-energy M-theory effective action. We discuss in detail the phase space of
the classical theory. We find the quantum solutions of the model and obtain the
positive norm Hilbert space of states. Finally, the correspondence between wave
functions and classical solutions is outlined.

</DOC>
<DOC>
<DOCNO> 67977 </DOCNO>
Strings and Branes in Nonabelian Gauge Theory


  It is an old speculation that SU(N) gauge theory can alternatively be
formulated as a string theory. Recently this subject has been revived, in the
wake of the discovery of D-branes. In particular, it has been argued that at
least some conformally invariant cousins of the theory have such a string
representation. This is a pedagogical introduction to these developments for
non-string theorists. Some of the existing arguments are simplified.

</DOC>
<DOC>
<DOCNO> 9628 </DOCNO>
Nonlinear voltage dependence of the shot noise in mesoscopic degenerate


  It is shown that measurements of zero-frequency shot-noise can provide
information on electron-electron interaction, because the strong interaction
results in the nonlinear voltage dependence of the shot noise in metallic
wires. This is due to the fact that the Wiedemann-Franz law is no longer valid
in the case of considerable electron-electron interaction. The deviations from
this law increase the noise power and make it dependent strongly on the ratio
of electron-electron and electron-impurity scattering rates.

</DOC>
<DOC>
<DOCNO> 7763 </DOCNO>
Anomalous Hopping Exponents of Ultrathin Films of Metals


  The temperature dependence of the resistance R(T) of ultrathin
quench-condensed films of Ag, Bi, Pb and Pd has been investigated. In the most
resistive films, R(T)=Roexp(To/T)^x, where x=0.75. Surprisingly, the exponent x
was found to be constant for a wide range of Ro and To in all four materials,
possibly implying a consistent underlying conduction mechanism. The results are
discussed in terms of several different models of hopping conduction.

</DOC>
<DOC>
<DOCNO> 150656 </DOCNO>
The Wess-Zumino-Witten term in non-commutative two-dimensional fermion


  We study the effective action associated to the Dirac operator in two
dimensional non-commutative Field Theory. Starting from the axial anomaly, we
compute the determinant of the Dirac operator and we find that even in the U(1)
theory, a Wess-Zumino-Witten like term arises.

</DOC>
<DOC>
<DOCNO> 7726 </DOCNO>
Chiral-glass transition and replica symmetry breaking of a


  Extensive equilibrium Monte Carlo simulations are performed for a
three-dimensional Heisenberg spin glass with the nearest-neighbor Gaussian
coupling to investigate its spin-glass and chiral-glass orderings. The
occurrence of a finite-temperature chiral-glass transition without the
conventional spin-glass order is established. Critical exponents characterizing
the transition are different from those of the standard Ising spin glass. The
calculated overlap distribution suggests the appearance of a peculiar type of
replica-symmetry breaking in the chiral-glass ordered state.

</DOC>
<DOC>
<DOCNO> 71533 </DOCNO>
pbarp and pp Elastic Scattering in a Multipole-Pomeron Model


  We assume that the Pomeron is a sum of Regge multipoles, each corresponding
to a finite gluon ladder. From a fit to the diffraction cone data of pp- and
pbarp- scattering we found that the triple pole is significant for the rise of
the ratio sigma_el/sigma_tot at high energies.

</DOC>
<DOC>
<DOCNO> 117485 </DOCNO>
The Effect of Resistivity on the Nonlinear Stage of the


  We present three-dimensional magnetohydrodynamic simulations of the nonlinear
evolution of the magnetorotational instability (MRI) with a non-zero Ohmic
resistivity. The properties of the saturated state depend on the initial
magnetic field configuration. In simulations with an initial uniform vertical
field, the MRI is able to support angular momentum transport even for large
resistivities through the quasi-periodic generation of axisymmetric radial
channel solutions rather than through the maintenance of anisotropic
turbulence. Simulations with zero net flux show that the angular momentum
transport and the amplitude of magnetic energy after saturation are
significantly reduced by finite resistivity, even at levels where the linear
modes are only slightly affected. This occurs at magnetic Reynolds numbers
expected in low, cool states of dwarf novae, these results suggest that finite
resistivity may account for the low and high angular momentum transport rates
inferred for these systems.

</DOC>
<DOC>
<DOCNO> 40314 </DOCNO>
New Results from CLEO


  The latest results from the CLEO collaboration are summarized. An update on
the status of the upgraded CLEO III detector is also included.

</DOC>
<DOC>
<DOCNO> 151332 </DOCNO>
M-Theory tested by N=2 Seiberg-Witten Theory


  Methods are reviewed for computing the instanton expansion of the
prepotential for N=2 Seiberg-Witten theory with non-hyperelliptic curves. These
results, when compared with the instanton expansion obtained from the
microscopic Lagrangian, provide detailed tests of M-theory. Group theoretic
regularities of F_ 1-inst allow one to "reverse engineer" a Seiberg-Witten
curve for SU(N) with two antisymmetric representations and N_f \leq 3
fundamental hypermultiplet representations, a result not yet available by other
methods. Consistency with M-theory requires a curve of infinite order.

</DOC>
<DOC>
<DOCNO> 9231 </DOCNO>
Spectral partitions on infinite graphs


  Statistical models on infinite graphs may exhibit inhomogeneous thermodynamic
behaviour at macroscopic scales. This phenomenon is of geometrical origin and
may be properly described in terms of spectral partitions into subgraphs with
well defined spectral dimensions and spectral weights. These subgraphs are
shown to be thermodynamically homogeneous and effectively decoupled.

</DOC>
<DOC>
<DOCNO> 118358 </DOCNO>
Black-Hole Transients and the Eddington Limit


  I show that the Eddington limit implies a critical orbital period P_crit(BH)
= 2d beyond which black-hole LMXBs cannot appear as persistent systems. The
unusual behaviour of GRO J1655-40 may result from its location close to this
critical period.

</DOC>
<DOC>
<DOCNO> 85381 </DOCNO>
Black hole entropy: certain quantum features


  The issue of black hole entropy is reexamined within a finite lattice
framework along the lines of Wheeler, 't Hooft and Susskind, with an additional
criterion to identify physical horizon states contributing to the entropy. As a
consequence, the degeneracy of physical states is lower than that attributed
normally to black holes. This results in corrections to the Bekenstein-Hawking
area law that are logarithmic in the horizon area. Implications for the
holographic entropy bound on bounded spaces are discussed. Theoretical
underpinnings of the criterion imposed on the states, based on the `quantum
geometry' formulation of quantum gravity, are briefly explained.

</DOC>
<DOC>
<DOCNO> 174450 </DOCNO>
Statistical signatures of critical behavior in small systems


  The cluster distributions of different systems are examined to search for
signatures of a continuous phase transition. In a system known to possess such
a phase transition, both sensitive and insensitive signatures are present;
while in systems known not to possess such a phase transition, only insensitive
signatures are present. It is shown that nuclear multifragmentation results in
cluster distributions belonging to the former category, suggesting that the
fragments are the result of a continuous phase transition.

</DOC>
<DOC>
<DOCNO> 101705 </DOCNO>
New Lorentz spaces for the restricted weak-type Hardy's inequalities


  Associated to the class of restricted-weak type weights for the Hardy
operator, we find a new class of Lorentz spaces for which the normability
property holds. This result is analogous to the characterization given by
Sawyer for the classical Lorentz spaces. We also show that these new spaces are
very natural to study the existence of equivalent norms described in terms of
the maximal function

</DOC>
<DOC>
<DOCNO> 10715 </DOCNO>
Wess-Zumino-Berry phase interference in spin tunneling at excited levels


  Macroscopic quantum coherence and spin-phase interference are studied between
excited levels in single-domain ferromagnetic particles in a magnetic field
along the hard anisotropy axis. The system has the general structure of
magnetocrystalline anisotropy, such as biaxial, trigonal, tetragonal, and
hexagonal symmetry. This study not only just yields the previous spin-phase
interference results for the ground state tunneling, but also provide a
generalization of the Kramers degeneracy to coherently spin tunneling at
low-lying excited states. These analytical results are found to be in good
agreement with the numerical diagonalization. We also discuss the transition
from quantum to classical behavior and the possible relevance to experiment.

</DOC>
<DOC>
<DOCNO> 101691 </DOCNO>
Characterizing Type I C*-algebras via Entropy


  Let A be a unital separable C*-algebra. We observe that A is type I if and
only if the CNT-entropy of every inner automorphism of A is zero.

</DOC>
<DOC>
<DOCNO> 71512 </DOCNO>
Remarks on Inflation and Noncommutative Geometry


  We briefly discuss some possible cosmological implications of noncommutative
geometry. While the noncommutativity we consider does not affect gravity, it
can play an important role in the dynamics of other fields that are present in
the early universe. We point out the possibility that noncommutativity may
cause inflation induced fluctuations to become non-gaussian and anisotropic,
and may modify the short distance dispersion relations.

</DOC>
<DOC>
<DOCNO> 150940 </DOCNO>
The Fate of the Radion in Models with Metastable Graviton


  We clarify some general issues in models where gravity is localized at
intermediate distances. We introduce the radion mode, which is usually
neglected, and we point out that its role in the model is crucial. We show that
the brane bending effects discussed in the literature can be obtained in a
formalism where the physical origin is manifest. The model violates positivity
of energy due to a negative tension brane, which induces a negative kinetic
term for the radion. The very same effect that violates positivity is
responsible for the recovery of conventional Einstein gravity at intermediate
distances.

</DOC>
<DOC>
<DOCNO> 11639 </DOCNO>
Phase diagram of congested traffic flow: an empirical study


  We analyze traffic data from a highway section containing one effective
on-ramp. Based on two criteria, local velocity variation patterns and expansion
(or nonexpansion) of congested regions, three distinct congested traffic states
are identified. These states appear at different levels of the upstream flux
and the on-ramp flux, thereby generating a phase diagram of the congested
traffic flow. Compared to our earliear reports (including cond-mat/9905292)
based on 14 day traffic data, the present paper uses a much larger data set
(107 days) and the analysis is carried in a more systematic way, which leads to
the modification of a part of interpretation in the earlier reports. Observed
traffic states are compared with recent theoretical analyses and both agreeing
and disagreeing features are found.

</DOC>
<DOC>
<DOCNO> 123055 </DOCNO>
The Sunyaev-Zel'dovich Effect with the Cosmic Background Imager


  We are engaged in a program with the Cosmic Background Imager (CBI), a
13-element interferometer recently installed at 5000 m in the Chilean Andes, to
measure H_0 with 10% accuracy through observations of the Sunyaev-Zel'dovich
effect in a sample of nearby clusters. We discuss the capabilities of this new
instrument and present our cluster sample and selection criteria, along with
results from detailed simulations. We also present preliminary observations of
Abell 478.

</DOC>
<DOC>
<DOCNO> 68746 </DOCNO>
Low Energy Theory for 2 flavors at High Density QCD


  We construct the effective Lagrangian describing the low energy excitations
for Quantum Chromodynamics with two flavors at high density. The non-linear
realization framework is employed to properly construct the low energy
effective theory. The light degrees of freedom, as required by 't Hooft anomaly
conditions, contain massless fermions which we properly include in the
effective Lagrangian. We also provide a discussion of the linearly realized
Lagrangian.

</DOC>
<DOC>
<DOCNO> 72057 </DOCNO>
Perturbative QCD factorization of $\pi \gamma^*\to \gamma(\pi)$ and


  We prove factorization theorem for the processes $\pi\gamma^*\to\gamma$ and
$\pi\gamma^*\to\pi$ to leading twist in the covariant gauge by means of the
Ward identity. Soft divergences cancel and collinear divergences are grouped
into a pion wave function defined by a nonlocal matrix element. The gauge
invariance and universality of the pion wave function are confirmed. The proof
is then extended to the exclusive $B$ meson decays $B\to\gamma l\bar\nu$ and
$B\to\pi l\bar\nu$ in the heavy quark limit. It is shown that a light-cone $B$
meson wave function, though absorbing soft dynamics, can be defined in an
appropriate frame. Factorization of the $B\to\pi l\bar\nu$ decay in $k_T$
space, $k_T$ being parton transverse momenta, is briefly discussed. We comment
on the extraction of the leading-twist pion wave function from experimental
data.

</DOC>
<DOC>
<DOCNO> 178907 </DOCNO>
Relativistic mean field description for the shears band mechanism in


  For the first time, the Relativistic Mean Field (RMF) model is applied to the
shears band recently observed in $_{37}^{84}$Rb. Signals of the appearance of
the shears mechanism, such as smooth decreases of the shears angle and of the
$B$(M1)/$B$(E2) ratio with keeping the nearly constant tilt angle, are well
reproduced. Thus it is shown that the microscopic RMF model can nicely describe
the shears band in this nucleus.

</DOC>
<DOC>
<DOCNO> 68734 </DOCNO>
Parity-breaking electromagnetic interactions in thermal QED_3


  We examine the parity violating terms generated by the box diagram in QED_3
at finite temperature. These lead to both extensive as well as non-extensive
effective actions, which have very distinct behavior in the long wavelength and
static limits. We discuss a large gauge Ward identity for the leading terms in
the static limit, whose solution coincides with the effective action proposed
earlier.

</DOC>
<DOC>
<DOCNO> 80925 </DOCNO>
An Order Parameter Reconciling Abelian and Center Dominance in SU(2)


  We analyze previously proposed order parameters for the confinement -
deconfinement transition in lattice SU(2) Yang-Mills theory, defined as vacuum
expectation value (v.e.v.) of monopole fields in abelian projection gauges. We
show that they exhibit some inconsistency in the treatment of small scales, due
to a violation of Dirac quantization condition for fluxes. We propose a new
order parameter avoiding this inconsistency. It can be interpreted as v.e.v. of
the field of a regular monopole in any abelian projection gauge, but it is
independent of the choice of the abelian projection. Furthermore, being
constructed in terms of surfaces of center vortices, it has also a natural
interpretation in the approach of center dominance.

</DOC>
<DOC>
<DOCNO> 7929 </DOCNO>
Theory of Diluted Magnetic Semiconductor Ferromagnetism


  We present a theory of carrier-induced ferromagnetism in diluted magnetic
semiconductors (III_{1-x} Mn_x V) which allows for arbitrary itinerant-carrier
spin polarization and dynamic correlations. Both ingredients are essential in
identifying the system's elementary excitations and describing their
properties. We find a branch of collective modes, in addition to the spin waves
and Stoner continuum which occur in metallic ferromagnets, and predict that the
low-temperature spin stiffness is independent of the strength of the exchange
coupling between magnetic ions and itinerant carriers. We discuss the
temperature dependence of the magnetization and the heat capacity.

</DOC>
<DOC>
<DOCNO> 67779 </DOCNO>
Universal Aspects of Gravity Localized on Thick Branes


  We study gravity in backgrounds that are smooth generalizations of the
Randall-Sundrum model, with and without scalar fields. These generalizations
include three-branes in higher dimensional spaces which are not necessarily
Anti-de Sitter far from the branes, intersecting brane configurations and
configurations involving negative tension branes. We show that under certain
mild assumptions there is a universal equation for the gravitational
fluctuations. We study both the graviton ground state and the continuum of
Kaluza-Klein modes and we find that the four-dimensional gravitational mode is
localized precisely when the effects of the continuum modes decouple at
distances larger than the fundamental Planck scale. The decoupling is
contingent only on the long-range behaviour of the metric from the brane and we
find a universal form for the corrections to Newton's Law. We also comment on
the possible contribution of resonant modes. Given this, we find general
classes of metrics which maintain localized four-dimensional gravity. We find
that three-brane metrics in five dimensions can arise from a single scalar
field source, and we rederive the BPS type conditions without any a priori
assumptions regarding the form of the scalar potential. We also show that a
single scalar field cannot produce conformally-flat locally intersecting brane
configurations or a p-brane in greater than (p+2)-dimensions.

</DOC>
<DOC>
<DOCNO> 80988 </DOCNO>
String Breaking in Four Dimensional Lattice QCD


  Virtual quark pair screening leads to breaking of the string between
fundamental representation quarks in QCD. For unquenched four dimensional
lattice QCD, this (so far elusive) phenomenon is studied using the recently
developed truncated determinant algorithm (TDA). The dynamical configurations
were generated on an Athlon 650 MHz PC. Quark eigenmodes up to 420 MeV are
included exactly in these TDA studies performed at low quark mass on large
coarse (but O($a^2$) improved) lattices. A study of Wilson line correlators in
Coulomb gauge extracted from an ensemble of 1000 two-flavor dynamical
configurations reveals evidence for flattening of the string tension at
distances R $\geq$ approximately 1 fm.

</DOC>
<DOC>
<DOCNO> 85448 </DOCNO>
Gravitational Entropy and Quantum Cosmology


  We investigate the evolution of different measures of ``Gravitational
Entropy'' in Bianchi type I and Lema\^itre-Tolman universe models.
  A new quantity behaving in accordance with the second law of thermodynamics
is introduced. We then go on and investigate whether a quantum calculation of
initial conditions for the universe based upon the Wheeler-DeWitt equation
supports Penrose's Weyl Curvature Conjecture, according to which the Ricci part
of the curvature dominates over the Weyl part at the initial singularity of the
universe. The theory is applied to the Bianchi type I universe models with dust
and a cosmological constant and to the Lema\^itre-Tolman universe models. We
investigate two different versions of the conjecture. First we investigate a
local version which fails to support the conjecture. Thereafter we construct a
non-local entity which shows more promising behaviour concerning the
conjecture.

</DOC>
<DOC>
<DOCNO> 123168 </DOCNO>
The deceleration of Giant Herbig-Haro Flows


  It has been recently discovered that spatially separated Herbig-Haro objects,
once considered unrelated, are linked within a chain that may extend for
parsecs in either direction of the embedded protostar forming a "giant
Herbig-Haro jet". Presently, several dozen of these giant flows have been
detected and the best documented example, the HH~34 system, shows a systematic
velocity decrease with distance on either side of the source. In this paper, we
have modeled giant jets by performing fully three-dimensional simulations of
overdense, radiatively cooling jets modulated with long-period
 (P $\sim$ several hundred years) and large amplitude sinusoidal velocity
variability at injection ($\Delta v \sim$ mean jet flow velocity). Allowing
them to travel over a distance well beyond the source, we have found that
multiple travelling pulses develop and their velocity indeed falls off smoothly
and systematically with distance. This deceleration is fastest if the jet is
pressure-confined, in which case the falloff in velocity is roughly consistent
with the observations. The deceleration occurs as momentum is transferred by
gas expelled sideways from the traveling pulses. The simulation of a
pressure-confined, steady-state jet with similar initial conditions to those of
the pulsed jet shows that the flow in this case experiences $acceleration$.
This result is thus an additional indication that the primary source of
deceleration in the giant flows $cannot$ be attributed to braking of the jet
head against the external medium.

</DOC>
<DOC>
<DOCNO> 169581 </DOCNO>
Quantum key distribution based on Greenberger-Horne-Zeilinger state


  An unsymmetrical quantum key distribution scheme is proposed, its security is
guaranteed by the correlation of the Greenberger-Horne-Zeilinger triplet state.
In the proposed protocol, the distribution of quantum states are unsymmetrical.
This unsymmetrical characteristic makes the transmission qubits (except the
loss qubits) be useful. Sequentially the proposed protocol has excellent
efficiency and security which are very useful in the practical application.

</DOC>
<DOC>
<DOCNO> 84410 </DOCNO>
Vacuum Polarization of Massive Scalar Fields on the Black Hole Horizon


  Vacuum polarization of massive scalar fields in a thermal state at arbitrary
temperature is studied near the horizon of a Reissner-Nordstr\"{o}m black hole.
We derived an analytic form of $<\phi^2>$ approximately in the large mass limit
near the black hole horizon. We uses the zeroth order WKB approximation and
power series expansion near the horizon for the Euclideanized mode function.
Our formula for the vacuum polarization shows regular behavior on the horizon
if the temperature of the scalar field is equal to the Hawking temperature of
the black hole. The finite part of the vacuum polarization agrees with the
result of the DeWitt-Schwinger approximation up to $O(m^{-4})$ which is the
next leading order of the expansion.

</DOC>
<DOC>
<DOCNO> 151643 </DOCNO>
SUSY and Goliath


  We investigate the `giant gravitons' of McGreevy, Susskind and Toumbas
[hep-th/0003075]. We demonstrate that these are BPS configurations which
preserve precisely the same supersymmetries as a `point-like' graviton. We also
show that there exist `dual' giant gravitons consisting of spherical branes
expanding into the AdS component of the spacetime. Finally, we discuss the
realization of the stringy exclusion principle within this expanded framework.

</DOC>
<DOC>
<DOCNO> 84742 </DOCNO>
Statistical Entropy of Schwarzschild Black Strings and Black Holes


  The statistical entropy of a Schwarzschild black string in five dimensions is
obtained by counting the black string states which form a representation of the
near-horizon conformal symmetry with a central charge. The statistical entropy
of the string agrees with its Bekenstein-Hawking entropy as well as that of the
Schwarzschild black hole in four dimensions. The choice of the string length
which gives the Virasoro algebra also reproduces the precise value of the
Bekenstein-Hawking entropy and lies inside the stability bound of the string.

</DOC>
<DOC>
<DOCNO> 118362 </DOCNO>
Evolution and surface abundances of red giants experiencing deep mixing


  We have calculated the evolution of low metallicity red giant stars under the
assumption of deep mixing between the convective envelope and the hydrogen
burning shell. We find that the extent of the observed abundance anomalies, and
in particular the universal O-Na anticorrelation, can be totally explained by
mixing which does not lead to significant helium enrichment of the envelope. On
the other hand, models with extremely deep mixing and strong helium enrichment
predict anomalies of sodium and oxygen, which are much larger than the observed
ones. This latter result depends solely on the nucleosynthesis inside the
hydrogen burning shell, but not on the details of the mixing descriptions.
These, however, influence the evolution of surface abundances with brightness,
which we compare with the limited observational material available. Our models
allow, nevertheless, to infer details on the depth and speed of the mixing
process in several clusters. Models with strong helium enrichment evolve to
high luminosities and show an increased mass loss. However, under peculiar
assumptions, red giants reach very high luminosities even without extreme
helium mixing. Due to the consequently increased mass loss, such models could
be candidates for blue horizontal branch stars, and, at the same time, would be
consistent with the observed abundance anomalies.

</DOC>
<DOC>
<DOCNO> 117869 </DOCNO>
Sachs-Wolfe effect in space-times with torsion


  Cartan torsion contribution to Sachs-Wolfe effect in the inflationary phase
of the Universe is discussed.From the COBE data of the microwave anisotropy is
possible to compute the spin-density in the Universe as $10^{16}$ mks units.The
spin-density fluctuations at the hadron era is shown to coincide with the
anisotropy temperature fluctuations.

</DOC>
<DOC>
<DOCNO> 80669 </DOCNO>
Incorporating Chiral Symmetry in Extrapolations of Octet Baryon Magnetic


  We explore methods of extrapolating lattice calculations of hadronic
observables to the physical regime, while respecting the constraints of chiral
symmetry and heavy quark effective theory. In particular, we extrapolate
lattice results for magnetic moments of the spin-1/2 baryon octet to the
physical pion mass and compare with experimental measurements. The success
previously reported for extrapolations of the nucleon magnetic moments carries
over to the Sigma baryons. A study of the residual discrepancies in the Xi
baryon moments suggests that it is important to have new simulation data with a
more realistic strange quark mass.

</DOC>
<DOC>
<DOCNO> 13387 </DOCNO>
Dynamical effects of the nanometer-sized polarized domains in


  Recent neutron scattering measurements performed on the relaxor ferroelectric
Pb[(Zn1/3Nb2/3)0.92Ti0.08]O3 (PZN-8%PT) in its cubic phase at 500 K, have
revealed an anomalous ridge of inelastic scattering centered ~0.2 A-1 from the
zone center (Gehring et al., Phys. Rev. Lett. 84, 5216 (2000)). This ridge of
scattering resembles a waterfall when plotted as a phonon dispersion diagram,
and extends vertically from the transverse acoustic (TA) branch near 4 meV to
the transverse optic (TO) branch near 9 meV. No zone center optic mode was
found. We report new results from an extensive neutron scattering study of pure
PZN that exhibits the same waterfall feature. We are able to model the dynamics
of the waterfall using a simple coupled-mode model that assumes a strongly
q-dependent optic mode linewidth Gamma1(q) that increases sharply near 0.2 A-1
as one approaches the zone center. This model was motivated by the results of
Burns and Dacol in 1983, who observed the formation of a randomly-oriented
local polarization in PZN at temperatures far above its ferroelectric phase
transition temperature. The dramatic increase in Gamma1 is believed to occur
when the wavelength of the optic mode becomes comparable to the size of the
small polarized micro-regions (PMR) associated with this randomly-oriented
local polarization, with the consequence that longer wavelength optic modes
cannot propagate and become overdamped. Below Tc=410 K, the intensity of the
waterfall diminishes. At lowest temperatures ~30 K the waterfall is absent, and
we observe the recovery of a zone center transverse optic mode near 10.5 meV.

</DOC>
<DOC>
<DOCNO> 122099 </DOCNO>
Nuclear star formation in the hot-spot galaxy NGC2903


  We present high-resolution near-infrared imaging obtained using adaptive
optics and HST/NICMOS, and ground-based spectroscopy of the hot-spot galaxy
NGC2903. Our near-infrared resolution imaging enables us to resolve the
infrared hot spots into individual young stellar clusters or groups of these.
The spatial distribution of the stellar clusters is not coincident with that of
the bright HII regions, as revealed by the HST/NICMOS Pa_alpha image. Overall,
the circumnuclear star formation in NGC2903 shows a ring-like morphology with
an approximate diameter of 625pc.
  The SF properties of the stellar clusters and HII regions have been studied
using the photometric and spectroscopic information in conjunction with
evolutionary synthesis models. The population of bright stellar clusters shows
a very narrow range of ages, 4-7 X 10^6 yr after the peak of star formation, or
absolute ages 6.5-9.5 X 10^6yr (for the assumed short-duration Gaussian
bursts), and luminosities similar to the clusters found in the Antennae
interacting galaxy. This population of young stellar clusters accounts for some
7-12% of the total stellar mass in the central 625pc of NGC2903. The HII
regions in the ring of star formation have luminosities close to that of the
super-giant HII region 30 Doradus, they are younger than the stellar clusters,
and will probably evolve into bright infrared stellar clusters similar to those
observed today. We find that the star formation efficiency in the central
regions of NGC2903 is higher than in normal galaxies, approaching the lower end
of infrared luminous galaxies.

</DOC>
<DOC>
<DOCNO> 70352 </DOCNO>
The structure of the light scalar mesons and QCD sum rules


  The structure of the light scalar mesons is elucidated by the investigation
of the S-matrix poles and the q-qbar spectral density in a coupled channel
model that includes pi-pi, K-Kbar and q-qbar channels. It is shown that the
dynamical origin of the sigma and f0(980) mesons is consistent with the
observed spectrum of the scalar states. The K-Kbar molecular picture of the
f0(980) is in good agreement with recent experimental data on the decay phi -
gamma pi pi from Novosibirsk.

</DOC>
<DOC>
<DOCNO> 11879 </DOCNO>
Light scattering from an amplifying medium bounded by a randomly rough


  We study by numerical simulations the scattering of $s$-polarized light from
a rough dielectric film deposited on the planar surface of a semi-infinite
perfect conductor. The dielectric film is allowed to be either active or
passive, situations that we model by assigning negative and positive values,
respectively, to the imaginary part $\epsilon_2$ of the dielectric constant of
the film. We study the reflectance ${\cal R}$ and the total scattered energy
${\cal U}$ for the system as functions of both $\epsilon_2$ and the angle of
incidence of the light. Furthermore, the positions and widths of the enhanced
backscattering and satellite peaks are discussed. It is found that these peaks
become narrower and higher when the amplification of the system is increased,
and that their widths scale linearly with $\epsilon_2$. The positions of the
backscattering peaks are found to be independent of $\epsilon_2$, while we find
a weak dependence on this quantity in the positions of the satellite peaks.

</DOC>
<DOC>
<DOCNO> 9564 </DOCNO>
Soft and non-soft structural transitions in disordered nematic networks


  Properties of disordered nematic elastomers and gels are theoretically
investigated with emphasis on the roles of non-local elastic interactions and
crosslinking conditions. Networks originally crosslinked in the isotropic phase
lose their long-range orientational order by the action of quenched random
stresses, which we incorporate into the affine-deformation model of nematic
rubber elasticity. We present a detailed picture of mechanical quasi-Goldstone
modes, which accounts for an almost completely soft polydomain-monodomain (P-M)
transition under strain as well as a ``four-leaf clover'' pattern in
depolarized light scattering intensity. Dynamical relaxation of the domain
structure is studied using a simple model. The peak wavenumber of the structure
factor obeys a power-law-type slow kinetics and goes to zero in true mechanical
equilibrium. The effect of quenched disorder on director fluctuation in the
monodomain state is analyzed. The random frozen contribution to the fluctuation
amplitude dominates the thermal one, at long wavelengths and near the P-M
transition threshold. We also study networks obtained by crosslinking
polydomain nematic polymer melts. The memory of initial director configuration
acts as correlated and strong quenched disorder, which renders the P-M
transition non-soft. The spatial distribution of the elastic free energy is
strongly dehomogenized by external strain, in contrast to the case of
isotropically crosslinked networks.

</DOC>
<DOC>
<DOCNO> 117711 </DOCNO>
Collapsars


  A variety of stellar explosions powered by black hole accretion are
discussed. All involve the failure of neutrino energy deposition to launch a
strong supernova explosion. A key quantity which determines the type of high
energy transient produced is the ratio of the engine operation time, $\rm
t_{engine}$, to the time for the explosion to break out of the stellar surface,
$\rm t_{bo}$. Stars with sufficient angular momentum produce collapsars --
black holes accreting rapidly through a disk -- in their centers. Collapsars
can occur in stars with a wide range of radii depending on the amount of
pre-collapse mass loss. The stellar radius and jet properties determine the
degree of beaming of the explosion. In some cases the stellar envelope serves
to focus the explosion to narrow beaming angles. The baryon loading of various
models for classical GRBs formed in massive stars is examined and the
consequences are explored. For $\rm t_{engine} > t_{bo}$, highly relativistic
outflow is possible and classical GRBs accompanied by supernovae can be
produced. In other cases hyper-energetic, asymmetric supernovae are produced.
Longer GRBs ($t \gtaprx 100 \s$) can be produced by fallback following a weak
neutrino-driven supernova explosion.

</DOC>
<DOC>
<DOCNO> 39906 </DOCNO>
Exclusive Leptoproduction of rho^0 Mesons from Hydrogen at Intermediate


  Measurements of the cross section for exclusive virtual-photoproduction of
rho^0 mesons from hydrogen are reported. The data were collected by the HERMES
experiment using 27.5 GeV positrons incident on a hydrogen gas target in the
HERA storage ring. The invariant mass W of the photon-nucleon system ranges
from 4.0 to 6.0 GeV, while the negative squared four-momentum Q^2 of the
virtual photon varies from 0.7 to 5.0 GeV^2. The present data together with
most of the previous data at W > 4 GeV are well described by a model that
infers the W-dependence of the cross section from the dependence on the Bjorken
scaling variable x of the unpolarized structure function for deep-inelastic
scattering. In addition, a model calculation based on Off-Forward Parton
Distributions gives a fairly good account of the longitudinal component of the
rho^0 production cross section for Q^2 > 2 GeV^2.

</DOC>
<DOC>
<DOCNO> 102058 </DOCNO>
Linearity of Artin groups of finite type


  Recent results on the linearity of braid groups are extended in two ways. We
generalize the Lawrence Krammer representation as well as Krammer's
faithfulness proof for this linear representation to Artin groups of finite
type.

</DOC>
<DOC>
<DOCNO> 13701 </DOCNO>
Viscoelasticity of Dilute Solutions of Semiflexible Polymers


  We show using Brownian dynamics simulations and theory how the shear
relaxation modulus G(t) of dilute solutions of relatively stiff semiflexible
polymers differs qualitatively from that of rigid rods. For chains shorter than
their persistence length, G(t) exhibits three time regimes: At very early
times, when the longitudinal deformation is affine, G(t) \sim t^{-3/4}. Over a
broad intermediate regime, during which the chain length relaxes, G(t) \sim
t^{-5/4}. At long times, $G(t) mimics that of rigid rods. A model of the
polymer as an effectively extensible rod with a frequency dependent elastic
modulus B(\omega) \sim (i \omega)^{3/4} quantitatively describes G(t)
throughout the first two regimes.

</DOC>
<DOC>
<DOCNO> 11336 </DOCNO>
The nature of the short wavelength excitations in vitreous silica:


  The dynamical structure factor (S(Q,E)) of vitreous silica has been measured
by Inelastic X-ray Scattering varying the exchanged wavevector (Q) at fixed
exchanged energy (E) - an experimental procedure that, contrary to the usual
one at constant Q, provides spectra with much better identified inelastic
features. This allows the first direct evidence of Brillouin peaks in the
S(Q,E) of SiO_2 at energies above the Boson Peak (BP) energy, a finding that
excludes the possibility that the BP marks the transition from propagating to
localised dynamics in glasses.

</DOC>
<DOC>
<DOCNO> 69848 </DOCNO>
Total Cross Sections and Event Properties from Real to Virtual Photons


  A model for total cross sections with virtual photons is presented. In
particular gamma*-p and gamma*-gamma* cross sections are considered. Our
approach extends on a model for photoproduction, where the total cross section
is subdivided into three distinct event classes: direct, VMD and anomalous.
With increasing photon virtuality, the latter two decrease in importance.
Instead Deep Inelastic Scattering dominates, with the direct class being the
O(alpha_s) correction thereof. Hence, the model provides a smooth transition
between the two regions. By the breakdown into different event classes, one may
aim for a complete picture of all event properties.

</DOC>
<DOC>
<DOCNO> 102451 </DOCNO>
Skein modules at the 4th roots of unity


  The Kauffman bracket skein modules, S(M,A), have been calculated for A=+1,-1,
for all 3-manifolds M by relating them to the SL(2,C)-character varieties. We
extend this description to the case when A is a 4-th root of 1 and M is either
a surface x [0,1] or a rational homology sphere (or its submanifold).

</DOC>
<DOC>
<DOCNO> 13462 </DOCNO>
Ballistic Quantum Transport: Effect of Geometrical Phases


  We study the influence of nonuniform magnetic fields on the magneto
conductance of mesoscopic microstructures. We show that the coupling of the
electron spin to the inhomogenous field gives rise to effects of the Berry
phase on ballistic quantum transport and discuss adiabaticity conditions
required to observe such effects. We present numerical results for different
ring geometries showing a splitting of Aharonov-Bohm conductance peaks for
single rings and corresponding signatures of the geometrical phase in weak
localization. The latter features can be qualitatively explained in a
semiclassical approach to quantum transport.

</DOC>
<DOC>
<DOCNO> 7768 </DOCNO>
Dislocation Mobility in Two-dimensional Lennard-Jones Material


  In seeking to understand at a microscopic level the response of dislocations
to stress we have undertaken to study as completely as possible the simplest
case: a single dislocation in a two dimensional crystal. The intention is that
results from this study will be used as input parameters in larger length scale
simulations involving many defects. We present atomistic simulations of defect
motion in a two-dimensional material consisting of atoms interacting through a
modified Lennard-Jones potential. We focus on the regime where the shear stress
is smaller than its critical value, where there is a finite energy barrier for
the dislocation to hop one lattice spacing. In this regime motion of the
dislocation will occur as single hops through thermal activation over the
barrier. Accurate knowledge of the barrier height is crucial for obtaining the
rates of such processes. We have calculated the energy barrier as a function of
two components of the stress tensor in a small system, and have obtained good
fits to a functional form with only a few adjustable parameters.

</DOC>
<DOC>
<DOCNO> 11755 </DOCNO>
Phase synchronization and noise-induced resonance in systems of coupled


  We study synchronization and noise-induced resonance phenomena in systems of
globally coupled oscillators, each possessing finite inertia. The behavior of
the order parameter, which measures collective synchronization of the system,
is investigated as the noise level and the coupling strength are varied, and
hysteretic behavior is manifested. The power spectrum of the phase velocity is
also examined and the quality factor as well as the response function is
obtained to reveal noise-induced resonance behavior.

</DOC>
<DOC>
<DOCNO> 39985 </DOCNO>
MSW Solutions to the Solar Neutrino Problem in Presence of Noisy Matter


  We study the effect of random matter density fluctuations in the sun on
resonant neutrino conversion in matter by solving numerically the evolution
equation for the neutrino system including the full effect of the random matter
density fluctuations of given amplitude and correlation length. In order to
establish the possible effect on the MSW solutions to the solar neutrino
problem we perform a global analysis of all the existing observables including
the measured total rates as well as the Super-Kamiokande measurement on the
time dependence of the event rates during the day and night and the recoil
electron energy spectrum. We find the effects of random noise to be larger for
small mixing angles and they are mostly important for correlation lengths in
the range few 100 km $\lesssim L_0\lesssim$ few 1000 km. They can be understood
as due to a parametric resonance occuring when the phase acquired by the
oscillating neutrino state on one fluctuation length L_0 is a multiple of
2$\pi$. We find that this resonant parametric condition is mainly achieved for
low energy neutrinos such as the pp-neutrinos and therefore its effect is
mostly seen on the total event rates while the other Super-Kamiokande
observables are very marginally sensitive to the presence of noise due to the
higher energy threshold.

</DOC>
<DOC>
<DOCNO> 102302 </DOCNO>
Complex Numbers in n Dimensions


  This monograph presents a detailed analysis of hypercomplex numbers in 2, 3
and 4 dimensions, then presents the properties of hypercomplex numbers in 5 and
6 dimensions. It continues with a detailed analysis of hypercomplex numbers in
n dimensions, and two distinct systems of commutative complex numbers are
described, of polar and planar types. Exponential forms of n-complex numbers
are given in each case, which depend on geometric variables. Azimuthal angles,
which are cyclic variables, appear in these forms at the exponent, and this
leads to the concept of residue for path integrals of n-complex functions. The
exponential function of an n-complex number is expanded in terms of functions
called in this paper cosexponential functions, which are generalizations to n
dimensions of the circular and hyperbolic sine and cosine functions. The
factorization of n-complex polynomials is discussed. The essence of this
monograph is the interplay between the algebraic, the geometric and the
analytic facets of the relations.

</DOC>
<DOC>
<DOCNO> 121447 </DOCNO>
The Faint Sky Variability Survey II: Initial Results


  We discuss the first results from the Faint Sky Variability Survey (Groot et
al. 2000). The data consist of V-band light curves, BVI colours, astrometry,
and morphology information on several hundred thousand point and extended
sources in the magnitude range V=17-25. We discuss the first 30 survey fields
covering an area of 8.4 square degrees towards moderate and high galactic
latitudes. We analyse the quality of and discuss our differential photometry
light curves. We employ statistical methods to select variable objects and
present example variable light curves. The distribution of the colours and
magnitudes of point sources in the survey is discussed and compared to galactic
star count models. Finally, we discuss our search for trans-Neptunian objects
in the FSVS fields observed towards ecliptic opposition.

</DOC>
<DOC>
<DOCNO> 102348 </DOCNO>
Minuscule representations, invariant polynomials, and spectral covers


  Given a minuscule representation of a simple Lie algebra, we find an
algebraic model for the action of a regular element and show that these models
can be glued together over the adjoint quotient, viewed as the set of all
regular conjugacy classes of the Lie algebra. There are partial results in the
case of a quasiminuscule representation, and a conjecture in the case of a
general irreducible finite-dimensional representation. The method of proof is
to relate the question to a problem concerning holomorphic principal bundles
over cuspidal cubic curves.

</DOC>
<DOC>
<DOCNO> 150404 </DOCNO>
Four-point functions in N=2 superconformal field theories


  Four-point correlation functions of hypermultiplet bilinear composites are
analysed in N=2 superconformal field theory using the superconformal Ward
identities and the analyticity properties of the composite operator
superfields. It is shown that the complete amplitude is determined by a single
arbitrary function of the two conformal cross-ratios of the space-time
variables.

</DOC>
<DOC>
<DOCNO> 68688 </DOCNO>
Diquark composites in the color superconducting phase of two flavor


  We study the Bethe-Salpeter equations for spin zero diquark composites in the
color superconducting phase of N_f=2 cold dense QCD. The explicit form of the
spectrum of the diquarks, containing an infinite tower of narrow (at high
density) resonances, is derived. It is argued that there are five
pseudo-Nambu-Goldstone bosons (pseudoscalars) that remain almost massless at
large chemical potential. These five pseudoscalars, along with the massless
quarks of the third color should play an important role in the infrared
dynamics of N_f=2 dense QCD.

</DOC>
<DOC>
<DOCNO> 170614 </DOCNO>
Lorentz Invariant Superluminal Tunneling


  It is shown that superluminal optical signalling is possible without
violating Lorentz invariance and causality via tunneling through photonic band
gaps in inhomogeneous dielectrics of a special kind.

</DOC>
<DOC>
<DOCNO> 68115 </DOCNO>
Hadronic in-Medium Effects with Elementary Probes


  The sensitivity of dilepton production in elementary reactions of photons and
pions with nuclei on in-medium changes of hadronic properties is studied. It is
shown that this sensitivity is comparable to that encountered in
ultrarelativistic heavy-ion collisions. It is also shown how a significant
broadening of the mesons affects other photonuclear processes.

</DOC>
<DOC>
<DOCNO> 70611 </DOCNO>
Wall and Anti-Wall in the Randall-Sundrum Model and A New Infrared


  An approach to find the field equation solution of the Randall-Sundrum model
with the $S^1/Z_2$ extra axis is presented. We closely examine the infrared
singularity. The vacuum is set by the 5 dimensional Higgs field. Both the
domain-wall and the anti-domain-wall naturally appear, at the {\it ends} of the
extra compact axis, by taking a {\it new infrared regularization}. The
stability is guaranteed from the outset by the kink boundary condition. A {\it
continuous} (infrared-)regularized solution, which is a truncated {\it Fourier
series} of a {\it discontinuous} solution, is utilized.The ultraviolet-infrared
relation appears in the regularized solution.

</DOC>
<DOC>
<DOCNO> 40650 </DOCNO>
BES Recent Results and Future Plans


  We report the preliminary R values for all the 85 energy points scanned in
the energy region of 2-5 GeV with the upgraded Beijing Spectrometer (BESII) at
Beijing Electron Positron Collider (BEPC). Preliminary results from the J/psi
data collected with both BESI and BESII are presented. Measurements of the
branching fraction of the psi(2S) decays and the psi(2S) resonance parameters
are reported. The future plans, i.e. significantly upgrade the machine and
detector are also discussed.

</DOC>
<DOC>
<DOCNO> 12610 </DOCNO>
Ideal Spin Filters: Theoretical Study of Electron Transmission Through


  It is predicted that certain atomically ordered interfaces between some
ferromagnetic metals (F) and semiconductors (S) should act as ideal spin
filters that transmit electrons only from the majority spin bands or only from
the minority spin bands of the F to the S at the Fermi energy, even for F with
both majority and minority bands at the Fermi level. Criteria for determining
which combinations of F, S and interface should be ideal spin filters are
formulated. The criteria depend only on the bulk band structures of the S and F
and on the translational symmetries of the S, F and interface. Several examples
of systems that meet these criteria to a high degree of precision are
identified. Disordered interfaces between F and S are also studied and it is
found that intermixing between the S and F can result in interfaces with spin
anti-filtering properties, the transmitted electrons being much less spin
polarized than those in the ferromagnetic metal at the Fermi energy. A patent
application based on this work has been commenced by Simon Fraser University.

</DOC>
<DOC>
<DOCNO> 70281 </DOCNO>
Gluon condensates at finite temperature


  We consider various special cases of gluon condensates at finite temperature.
The gluon condensate for an ideal gas of gluons with a given vacuum expectation
value is introduced for the sake of comparison with that calculated using the
recent finite temperature lattice gauge simulations for a pure Yang-Mills SU(3)
gauge theory at the known critical temperature. We extend this comparison using
the high precision lattice data for two light dynamical quarks. The
investigation of these three cases show some interesting differences arising
from the strong interaction alone and in the presence of quarks. In this
context we discuss some newer simulations for heavier quarks and other
properties related to gluon condensation.

</DOC>
<DOC>
<DOCNO> 10777 </DOCNO>
Excitonic Funneling in Extended Dendrimers with Non-Linear and Random


  The mean first passage time (MFPT) for photoexcitations diffusion in a
funneling potential of artificial tree-like light-harvesting antennae
(phenylacetylene dendrimers with generation-dependent segment lengths) is
computed. Effects of the non-linearity of the realistic funneling potential and
slow random solvent fluctuations considerably slow down the center-bound
diffusion beyond a temperature-dependent optimal size. Diffusion on a
disordered Cayley tree with a linear potential is investigated analytically. At
low temperatures we predict a phase in which the MFPT is dominated by a few
paths.

</DOC>
<DOC>
<DOCNO> 99579 </DOCNO>
On $\alpha $-Critical Edges in K\"{o}nig-Egerv\'{a}ry Graphs


  The stability number of a graph G, denoted by alpha(G), is the cardinality of
a stable set of maximum size in G. If alpha(G-e) > alpha(G), then e is an
alpha-critical edge, and if mu(G-e) < mu(G), then e is a mu-critical edge,
where mu(G) is the cardinality of a maximum matching in G. G is a
Koenig-Egervary graph if alpha(G) + mu(G) equals its order. Beineke, Harary and
Plummer have shown that the set of alpha-critical edges of a bipartite graph is
a matching. In this paper we generalize this statement to Koenig-Egervary
graphs. We also prove that in a Koenig-Egervary graph alpha-critical edges are
also mu-critical, and that they coincide in bipartite graphs. We obtain that
for any tree its stability number equals the sum of the cardinality of the set
of its alpha-critical vertices and the size of the set of its alpha-critical
edges. Eventually, we characterize the Koenig-Egervary graphs enjoying this
property.

</DOC>
<DOC>
<DOCNO> 117199 </DOCNO>
Photoabsorption spectra in the continuum of molecules and atomic


  We present linear response theories in the continuum capable of describing
photoionization spectra and dynamic polarizabilities of finite systems with no
spatial symmetry. Our formulations are based on the time-dependent local
density approximation with uniform grid representation in the three-dimensional
Cartesian coordinate. Effects of the continuum are taken into account either
with a Green's function method or with a complex absorbing potential in a
real-time method. The two methods are applied to a negatively charged cluster
in the spherical jellium model and to some small molecules (silane, acetylene
and ethylene).

</DOC>
<DOC>
<DOCNO> 12576 </DOCNO>
Effective Field Theory Power Counting at Finite Density


  Effective field theory is applied to finite-density systems with an
unnaturally large scattering length, such as neutron matter. A new
organizational scheme is identified and connected with an expansion in inverse
powers of the number of space-time dimensions. This power counting allows for
analytic calculations in many-body systems and reproduces the hole-line
expansion of traditional nuclear physics.

</DOC>
<DOC>
<DOCNO> 120937 </DOCNO>
HEXTE Detections of Hard X-Ray Tails in Sco X-1


  We report the detection of a non-thermal hard X-ray component from Sco X-1
based upon the analysis of 20-220 keV spectra obtained with the HEXTE
experiment on-board the RXTE satellite. We find that the addition of a
power-law component to a thermal bremsstrahlung model is required to achieve a
good fit in 5 of 16 observations analyzed. Using PCA data we were able to track
the movement of the source along the Z diagram, and we found that the presence
of the hard X-ray tail is not confined to a specific Z position. However, we do
observe an indication that the power law index hardens with increasing mass
accretion rate, as indicated from the position on the Z diagram. We find that
the derived non-thermal luminosities are at order of 10% of that derived for
the brightest of the atoll sources.

</DOC>
<DOC>
<DOCNO> 151150 </DOCNO>
Space-Time Noncommutative Field Theories And Unitarity


  We study the perturbative unitarity of noncommutative scalar field theories.
Field theories with space-time noncommutativity do not have a unitary S-matrix.
Field theories with only space noncommutativity are perturbatively unitary.
This can be understood from string theory, since space noncommutative field
theories describe a low energy limit of string theory in a background magnetic
field. On the other hand, there is no regime in which space-time noncommutative
field theory is an appropriate description of string theory. Whenever
space-time noncommutative field theory becomes relevant massive open string
states cannot be neglected.

</DOC>
<DOC>
<DOCNO> 10876 </DOCNO>
Measurement of Transport Lifetime in a Cuprate Superconductor


  We report measurements of the phase of the conductivity, $\phi_\sigma\equiv
arg(\sigma)$, in the normal state of a $Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta}$
(BSCCO) thin film from 0.2-1.0 THz. From $\phi_\sigma$ we obtain the time delay
of the current response, $\tau_\sigma\equiv\phi_\sigma/\omega$. After
discovering a systematic error in the data analysis, the extracted
$\tau_\sigma$ has changed from that reported earlier. The revised data is shown
in the sole figure below. Analysis and discussion of these data will follow.

</DOC>
<DOC>
<DOCNO> 83272 </DOCNO>
Accuracy, Coverage, and Speed: What Do They Mean to Users?


  Speech is becoming increasingly popular as an interface modality, especially
in hands- and eyes-busy situations where the use of a keyboard or mouse is
difficult. However, despite the fact that many have hailed speech as being
inherently usable (since everyone already knows how to talk), most users of
speech input are left feeling disappointed by the quality of the interaction.
Clearly, there is much work to be done on the design of usable spoken
interfaces. We believe that there are two major problems in the design of
speech interfaces, namely, (a) the people who are currently working on the
design of speech interfaces are, for the most part, not interface designers and
therefore do not have as much experience with usability issues as we in the CHI
community do, and (b) speech, as an interface modality, has vastly different
properties than other modalities, and therefore requires different usability
measures.

</DOC>
<DOC>
<DOCNO> 118256 </DOCNO>
An Empirical Test and Calibration of H II Region Diagnostics


  We present spectrophotometry in the 3600-9700 A region for a sample of 39 H
II regions in the Galaxy and Magellanic Clouds, for which independent
information is available on the spectral types and effective temperatures of
the ionizing stars. The spectra have been used to evaluate nebular diagnostics
of stellar temperature, metal abundance, and ionization parameter, and compare
the observed behavior of the line indices with predictions of nebular
photoionization models. We observe a strong degeneracy between forbidden-line
sequences produced by changes in stellar Teff and metal abundance, which
severely complicates the application of many forbidden-line diagnostics to
extragalactic H II regions. Our data confirm however that the Edmunds and Pagel
[O II]+[O III] abundance index and the Vilchez and Pagel `eta' index provide
more robust diagnostics of metal abundance and stellar effective temperature,
respectively. A comparison of the fractional helium ionization of the H II
regions with stellar temperature confirms the reliability of the spectral type
vs Teff calibration for the relevant temperature range Teff < 38000 K. We use
empirical relations between the nebular hardness indices and Teff to
reinvestigate the case for systematic variations in the stellar effective
temperatures and the upper IMFs of massive stars in extragalactic H II regions.
The data are consistent with a significant softening of the ionizing spectra
(consistent with cooler stellar temperatures) with increasing metal abundance,
especially for Z less than solar. However unresolved degeneracies between Z and
Teff still complicate the interpretation of this result.

</DOC>
<DOC>
<DOCNO> 101178 </DOCNO>
New Permanent Estimators via Non-Commutative Determinants


  We introduce a new notion of the determinant, called symmetrized determinant,
for a square matrix with the entries in an associative algebra $\AA$. The
monomial expansion of the symmetrized determinant is obtained from the standard
expansion of the commutative determinant by averaging the products of entries
of the matrix in all possible orders. We show that for any fixed
finite-dimensional associative algebra $\AA$, the symmetrized determinant of an
$n\times n$ matrix with the entries in $\AA$ can be computed in polynomial in
$n$ time (the degree of the polynomial is linear in the dimension of $\AA$).
Then, for every associative algebra $\AA$ endowed with a scalar product and
unbiased probability measure, we construct a randomized polynomial time
algorithm to estimate the permanent of non-negative matrices. We conjecture
that if $\AA=\Mat(d, {\Bbb R})$ is the algebra of $d\times d$ real matrices
endowed with the standard scalar product and Gaussian measure, the algorithm
approximates the permanent of a non-negative $n \times n$ matrix within
$O(\gamma_d^n)$ factor, where $\lim_{d \longrightarrow +\infty} \gamma_d=1$.
Finally, we provide some informal arguments why the conjecture might be true.

</DOC>
<DOC>
<DOCNO> 121134 </DOCNO>
Far-Ultraviolet Spectra of AGN: First Results from FUSE


  Composite spectra derived from HST observations of moderate redshift (z~1)
quasars show that the peak of the spectral energy distribution is at ~1000 A,
and that the ionizing continuum falls off smoothly to shorter wavelengths as
$f_\nu \sim \nu^{-1.8}$. HUT and FUSE observations of nearby AGN (e.g., 3C 273)
show similar results. FUSE spectra reveal a wealth of detail in the 912-1200 A
spectral range, including multi-component intrinsic absorption in the O VI
doublet and Lyb, and surprisingly strong narrow-line emission from O VI
1032,1038. Monitoring observations of AGN below 1200 A are feasible, and such
experiments could help to unravel the structure of intrinsic absorbers in AGN
as well as the highest ionization portions of the broad-line region.

</DOC>
<DOC>
<DOCNO> 101579 </DOCNO>
The meromorphic non-integrability of the three-body problem


  We study the planar three-body problem and prove the absence of a complete
set of complex meromorphic first integrals in a neighborhood of the Lagrangian
solution. We use the Ziglin's method and study the monodromy group of the
corresponding normal variational equations.

</DOC>
<DOC>
<DOCNO> 68699 </DOCNO>
D-Brane Recoil and Supersymmetry Obstruction


  We discuss a model in which our universe is pictured as a recoiling Dirichlet
brane: we find that a proper treatment of the recoil leads naturally to
supersymmetry obstruction on the four-dimensional world. An essential feature
of our approach is the fact that the underlying worldsheet sigma model is
non-critical, and the Liouville mode plays the role of the target time. Also,
the extra bulk dimensions are viewed as sigma model couplings, and as such have
to be averaged by appropriate summation over worldsheet genera. The recoiling
brane is in an excited state rather than its ground state, to which it relaxes
asymptotically in time, restoring supersymmetry. We also find that the
excitation energy, which is considered as the observable effective cosmological
`constant' on the brane, is naturally small and can accommodate upper bounds
from observations.

</DOC>
<DOC>
<DOCNO> 11697 </DOCNO>
Does matter wave amplification work for fermions?


  We discuss the relationship between bosonic stimulation, density
fluctuations, and matter wave gratings. It is shown that enhanced stimulated
scattering, matter wave amplification and atomic four-wave mixing are in
principle possible for fermionic or non-degenerate samples if they are prepared
in a cooperative state. In practice, there are limitations by short coherence
times.

</DOC>
<DOC>
<DOCNO> 121694 </DOCNO>
CCD Photometry of the Globlular Cluster NGC 5986 and its


  We have obtained new CCD BV photometry of the little-studied southern
Galactic globular cluster NGC 5986, including light curves of 5 of its RR Lyrae
variables. The cluster's red giant branch bump is detected for the first time
at V = 16.47 +- 0.03. We derive a reddening and true distance modulus of E(B-V)
= 0.29 +- 0.02 and (m-M)_0 = 15.15 +- 0.10, respectively. The cluster's
color-magnitude diagram reveals a mostly blue horizontal branch, like that of
M13 or M2, and quite unlike M3; yet all of these clusters have nearly identical
metallicities ([Fe/H]_CG97 = -1.35). We show that the RR Lyrae variables in NGC
5986 are about 0.2 mag brighter on average than those in M3, an important
exception to the often-employed, universal M_V(RR)--[Fe/H] relation. Finally,
we note that NGC 5986 contains two luminous stars with spectral types A-F,
which are likely to be post-asymptotic-giant-branch (PAGB) objects. The V-band
luminosity function (LF) of such yellow PAGB stars is a promising standard
candle. We suggest that the LF is sharply peaked at M_V(PAGB) = -3.28 +- 0.07.

</DOC>
<DOC>
<DOCNO> 85647 </DOCNO>
Behavior of Cosmological Perturbations in the Brane-World Mode


  In this paper we present a gauge-invariant formalism for perturbations of the
brane-world model developed by the author, A. Ishibashi and O. Seto recently,
and analyze the behavior of cosmological perturbations in a spatially flat
expanding universe realized as a boundary 3-brane in AdS$^5$ in terms of this
formalism. For simplicity we restrict arguments to scalar perturbations. We
show that the behavior of cosmological perturbations on superhorizon scales in
the brane-world model is the same as that in the standard no-extradimension
model, irrespective of the initial condition for bulk perturbations, in the
late stage when the cosmic expansion rate $H$ is smaller than the inverse of
the bulk curvature scale $\ell$. Further, we give rough estimates which
indicate that in the early universe when $H$ is much larger than $1/\ell$,
perturbations in these two models behave quite differently, and the
conservation of the Bardeen parameter does not hold for superhorizon
perturbations in the brane-world model.

</DOC>
<DOC>
<DOCNO> 70569 </DOCNO>
Form Factors of the Nucleon in a Selfconsistent Chiral Model


  In the present paper we extend the Schwinger model of the nucleon to the
inclusion of loop corrections. Starting from a chiral model of nucleon and
delta for the mesons $\pi,\rho$ and $A_1$ we extend our nonperturbative
sefconsistent regularisation scheme to the calculation of the nucleon form
factors. Chiral symmetry requires loops according to the interactions ${\cal
L}_{\pi\pi\rho}, {\cal L}_{\rho\rho\rho}, {\cal L}_{\rho\pi A_1}, {\cal
L}_{\rho A_1 A_1}$.The coupling constants are strictly introduced by chiral
symmetry. The use of low energy theorems and SU(3) relations allow an otherwise
parameterfree calculation of the form factors of the nucleon.

</DOC>
<DOC>
<DOCNO> 71334 </DOCNO>
POMWIG : HERWIG for diffractive interactions


  We have modified the HERWIG event generator to incorporate diffractive
interactions. All standard HERWIG hard subprocesses are available.

</DOC>
<DOC>
<DOCNO> 68438 </DOCNO>
Does Efficiency of High Energy Collisions Depend on a Hard Scale?


  The multiplicity of charged hadrons in the current fragmentation region of
both the c.m.s. and the Breit frame of deep inelastic scattering is calculated
and compared with the HERA data. The results are in agreeement with Yang's
hypothesis that the efficiency of high energy processes increases at larger
momentum transfer.

</DOC>
<DOC>
<DOCNO> 12935 </DOCNO>
The Reverse Brazil Nut Problem: Competition between Percolation and


  In the Brazil nut problem (BNP), hard spheres with larger diameters rise to
the top. There are various explanations (percolation, reorganization,
convection), but a broad understanding or control of this effect is by no means
acheived. A theory is presented for the crossover from the BNP to the reverse
Brazil nut problem (RBNP) based on a competition between the percolation effect
and the condensation of hard spheres. The crossover condition is determined,
and the theoretical predictions are compared to Molecular Dynamics simulations
in two and three dimensions.

</DOC>
<DOC>
<DOCNO> 120151 </DOCNO>
The Synthesis Telescope at the Dominion Radio Astrophysical Observatory


  We describe an aperture synthesis radio telescope optimized for studies of
the Galactic interstellar medium (ISM), providing the ability to image extended
structures with high angular resolution over wide fields. The telescope
produces images of atomic hydrogen emission using the 21-cm HI spectral line,
and, simultaneously, continuum emission in two bands centred at 1420 MHz and
408 MHz, including linearly polarized emission at 1420 MHz, with synthesized
beams of 1 degree and 3.4 degrees at the respective frequencies.

</DOC>
<DOC>
<DOCNO> 170780 </DOCNO>
Generalized Neutrino Equations from the Einstein Postulate


  I discuss generalized spin-1/2 massless equations for neutrinos. They have
been obtained by Gersten's method for derivation of arbitrary-spin equations.
Possible physical consequences are discussed.

</DOC>
<DOC>
<DOCNO> 121204 </DOCNO>
The Milky Way in Molecular Clouds: A New Complete CO Survey


  New large-scale CO surveys of the first and second Galactic quadrants and the
nearby molecular cloud complexes in Orion and Taurus, obtained with the CfA 1.2
m telescope, have been combined with 31 other surveys obtained over the past
two decades with that instrument and a similar telescope on Cerro Tololo in
Chile, to produce a new composite CO survey of the entire Milky Way. The survey
consists of 488,000 spectra that Nyquist or beamwidth (1/8-deg) sample the
entire Galactic plane over a strip 4-10 deg wide in latitude, and beamwidth or
1/4-deg sample nearly all large local clouds at higher latitudes.
  A map of molecular column density predicted from complete and unbiased
far-infrared and 21 cm surveys of the Galaxy was used both to determine the
completeness of the present survey and to extrapolate it to the entire sky at
|b| < 32 deg. The close agreement of the observed and predicted maps implies
that only ~2% of the total CO emission at |b| < 32 deg lies outside our current
sampling. Taking into account this small amount of unobserved emission, the
mean molecular column density decreases from ~3 E20 cm-2 at |b| = 5 deg to ~0.1
E20 cm-2 at |b| = 30 deg.
  The ratio of the predicted molecular column density map to the observed CO
intensity map provides a calibration of the CO-to-H2 mass conversion factor X =
N(H2)/Wco. Out of the Galactic plane (|b| > 5 deg), X shows little systematic
variation with latitude from a mean value of 1.8 +/- 0.3 E20 cm-2 K-1 km-1 s.
Given the large sky area and large quantity of CO data analyzed, we conclude
that this is the most reliable measurement to date of the mean X value in the
solar neighborhood.

</DOC>
<DOC>
<DOCNO> 121506 </DOCNO>
HST as a reliable astrometric tool for pulsar astronomy: the cases of


  The quest for the distance of the Vela and Geminga pulsars yielded, so far, a
set of four WFPC2 images for each object. The availability of couples of images
taken at the same period of the year, thus affected by the same parallactic
displacement, prompted us to use Vela and Geminga as test cases to assess the
reliability of HST astrometry.

</DOC>
<DOC>
<DOCNO> 68014 </DOCNO>
Relic Neutrinos and Z-Resonance Mechanism for Highest-Energy Cosmic Rays


  The origin of the highest-energy cosmic rays remains elusive. The decay of a
superheavy particle (X) into an ultra-energetic neutrino which scatters from a
relic (anti-)neutrino at the Z-resonance has attractive features. Given the
necessary X mass of $10^{14\sim15}$ GeV, the required lifetime, $10^{15\sim16}$
y, renders model-building a serious challenge but three logical possibilities
are considered: (i) X is a Higgs scalar in SU(15) belonging to high-rank
representation, leading to {\it power}-enhanced lifetime; (ii) a global X
quantum number has {\it exponentially}-suppressed symmetry-breaking by
instantons; and (iii) with additional space dimension(s) localisation of X
within the real-world brane leads to {\it gaussian} decay suppression, the most
efficient of the suppression mechanisms considered.

</DOC>
<DOC>
<DOCNO> 13578 </DOCNO>
Structural and superconducting transition in selenium under high


  First-principles calculations are performed for electronic structures of two
high pressure phases of solid selenium, $\beta$-Po and bcc.
  Our calculation reproduces well the pressure-induced phase transition from
$\beta$-Po to bcc observed in selenium.
  The calculated transition pressure is 30 GPa lower than the observed one, but
the calculated pressure dependence of the lattice parameters agrees fairly well
with the observations in a wide range of pressure.
  We estimate the superconducting transition temperature $T_{\rm c}$ of both
the $\beta$-Po and the bcc phases by calculating the phonon dispersion and the
electron-phonon interaction on the basis of density-functional perturbation
theory.
  The calculated $T_{\rm c}$ shows a characteristic pressure dependence, i.e.
it is rather pressure independent in the $\beta$-Po phase, shows a
discontinuous jump at the transition from $\beta$-Po to bcc, and then decreases
rapidly with increasing pressure in the bcc phase.

</DOC>
<DOC>
<DOCNO> 120307 </DOCNO>
The HI Content of Spirals. II. Gas Deficiency in Cluster Galaxies


  We derive the atomic hydrogen content for a total of 1900 spirals in the
fields of eighteen nearby clusters. By comparing the HI deficiency
distributions of the galaxies inside of and outside of one Abell radius of each
cluster, we find that two thirds of the clusters in our sample show a dearth of
neutral gas in their interiors. Possible connections between the gaseous
deficiency and the characteristics of both the underlying galaxies and their
environment are investigated in order to gain insight into the mechanisms
responsible for HI depletion. While we do not find a statistically significant
variation of the fraction of HI-deficient spirals in a cluster with its global
properties, a number of correlations emerge that argue in favor of the
interplay between spiral disks and their environment. In the clusters in which
neutral gas deficiency is pronounced, we see clear indications that the degree
of HI depletion is related to the morphology of the galaxies and not to their
optical size: early-type and, probably, dwarf spirals are more easily emptied
of gas than the intermediate Sbc--Sc types. The wealth of 21-cm data collected
for the Virgo region has made it possible to study the 2D pattern of HI
deficiency in that cluster. We also find evidence that gas-poor spirals in
HI-deficient clusters move on orbits more radial than those of the gas-rich
objects. The implications of all these results on models of how galaxies
interact with their environment are reviewed. Hydrodynamic effects appear as
the most plausible cause of HI removal. (abridged)

</DOC>
<DOC>
<DOCNO> 68663 </DOCNO>
Magnetic Moments of Decuplet Baryons in Light Cone QCD


  We calculate the magnetic moments of decuplet baryons containing strange
quarks within the framework of light cone QCD sum rules taking into account the
SU(3) flavor symmetry breaking effects. It is obtained that magnetic moments of
the neutral $\sso$ and $\xis0$ baryons are mainly determined by the SU(3)
breaking terms. A comparison of our results on the magnetic moments of the
decuplet baryons with the predictions of other approaches is presented.

</DOC>
<DOC>
<DOCNO> 152645 </DOCNO>
Ground State Energy of Massive Scalar Field Inside a Spherical Region in


  Using the zeta function regularization method we calculate the ground state
energy of scalar massive field inside a spherical region in the space-time of a
point-like global monopole. Two cases are investigated: (i) We calculate the
Casimir energy inside a sphere of radius $R$ and make an analytical analysis
about it. We observe that this energy may be positive or negative depending on
metric coefficient $\alpha$ and non-conformal coupling $\xi$. In the limit
$R\to\infty$ we found a zero result. (ii) In the second model we surround the
monopole by additional sphere of radius $r_0<R$ and consider scalar field
confined in the region between these two spheres. In the latter, the ground
state energy presents an additional contribution due to boundary at $r_0$ which
is divergent for small radius. Additional comments about renormalization are
considered.

</DOC>
<DOC>
<DOCNO> 10218 </DOCNO>
Theoretical Results for Sandpile Models of SOC with Multiple Topplings


  We study a directed stochastic sandpile model of Self-Organized Criticality,
which exhibits recurrent, multiple topplings, putting it in a separate
universality class from the exactly solved model of Dhar and Ramaswamy. We show
that in the steady-state all stable states are equally likely. Then we
explicitly derive a discrete dynamical equation for avalanches on the lattice.
By coarse-graining we arrive at a continuous Langevin equation for the
propagation of avalanches and calculate all the critical exponents
characterizing them. The avalanche equation is similar to the Edwards-Wilkinson
equation, but with a noise amplitude that is a threshold function of the local
avalanche activity, or interface height, leading to a stable absorbing state
when the avalanche dies. It represents a new type of absorbing state phase
transition.

</DOC>
<DOC>
<DOCNO> 120382 </DOCNO>
CO Observations of Luminous IR Galaxies at Intermediate Redshift


  We present new measurement of $^{12}$CO($J=1-0$) emission from 16 luminous
infrared galaxies (LIGs) at intermediate redshift ($cz \sim 10,000 - 50,000
{\rm km s^{-1}}$). These new data were selected by isolated and normal
morphology. The CO observations were performed using the NRO 45-m telescope.
Comparison of the CO and dust properties of the new result with those from
other CO measurements revealed characteristics of this sample: (1) It is the
deepest CO observations of IRAS galaxies at intermediate redshift without
strong interaction features. (2) It has typical properties of normal IRAS
galaxies in terms of star-formation efficiency, color-color diagrams and
galactic nuclear activity. (3) It has smaller gas-to-dust ratio than normal
IRAS galaxies. This can be explained by two-component dust model, and our
sample consists of most of warm dust.

</DOC>
<DOC>
<DOCNO> 39776 </DOCNO>
Spin Correlation in tt-bar Production from pp-bar Collisions at


  The D0 collaboration has performed a study of spin correlation in tt-bar
production for the process tt-bar to bb-bar W^+W^-, where the W bosons decay to
e-nu or mu-nu. A sample of six events was collected during an exposure of the
D0 detector to an integrated luminosity of approximately 125 pb^-1 of
sqrt{s}=1.8 TeV pp-bar collisions. The standard model (SM) predicts that the
short lifetime of the top quark ensures the transmission of any spin
information at production to the tt-bar decay products.
  The degree of spin correlation is characterized by a correlation coefficient
k. We find that k>-0.25 at the 68% confidence level, in agreement with the SM
prediction of k=0.88.

</DOC>
<DOC>
<DOCNO> 116874 </DOCNO>
A Super-Conducting Linac Injector for the BNL-Ags


  This paper reports on the feasibility study of a proton Super-Conducting
Linac (SCL) as a new injector to the Alternating Gradient Synchrotron (AGS) of
the Brookhaven National Laboratory (BNL). The Linac beam energy is in the range
of 1.5 to 2.4 GeV. The Beam intensity is adjusted to provide an average beam
power of 4 MW at the top energy of 24 GeV. The repetition rate of the SCL-AGS
facility is 5 beam pulses per second.

</DOC>
<DOC>
<DOCNO> 151131 </DOCNO>
Noncommutative Monopole at the Second Order in \theta


  We study the noncommutative U(2) monopole solution at the second order in the
noncommutativity parameter \theta^{ij}. We solve the BPS equation in
noncommutative super Yang-Mills theory to O(\theta^2), transform the solution
to the commutative description by the Seiberg-Witten (SW) map, and evaluate the
eigenvalues of the scalar field. We find that, by tuning the free parameters in
the SW map, we can make the scalar eigenvalues precisely reproduce the
configuration of a tilted D-string suspended between two parallel D3-branes.
This gives an example of how the ambiguities inevitable in the higher order SW
map are fixed by physical requirements.

</DOC>
<DOC>
<DOCNO> 70009 </DOCNO>
Calculation of hyperfine splitting in mesons using configuration


  The spin - spin mass splitting of light, heavy and mixed mesons are described
within a good accuracy in the potential model with screened potential. We
conclude that the long - distance part of the potential cannot be pure scalar
and that a vector - scalar mixture is favoured. With the same parameters which
gives correct average mass spectrum excellent spin - spin splittings of heavy
quarkonia is obtained. The results are obtained by going beyond usually used
perturbation method, namely using configuration interaction approach.

</DOC>
<DOC>
<DOCNO> 70923 </DOCNO>
Large lepton flavor mixings in $SU(6)\times SU(2)_R$ model


  The lepton masses and mixings are studied on the basis of string inspired
$SU(6)\times SU(2)_R$ model with global flavor symmetries. Provided that
sizable mixings between lepton doublets $L$ and Higgsino-like fields $H_d$ with
even R-parity occur and that seesaw mechanism is at work in the neutrino
sector, the model can yield a large mixing angle solution with $\tan
\theta_{12}, \tan \theta_{23} = \O(\sqrt{\l})$ $({\l}= 0.22)$, which is
consistent with the recent experimental data on atmospheric and solar
neutrinos. In the solution Dirac mass hierarchies in the neutrino sector cancel
out with the heavy Majorana sector in large part due to seesaw mechanism.
Hierarchical pattern of charged lepton masses can be also explained.

</DOC>
<DOC>
<DOCNO> 102830 </DOCNO>
Semi-infinite cohomology and superconformal algebras


  We describe representations of certain superconformal algebras in the
semi-infinite Weil complex related to the loop algebra of a complex
finite-dimensional Lie algebra and in the semi-infinite cohomology. We show
that in the case where the Lie algebra is endowed with a non-degenerate
invariant symmetric bilinear form, the relative semi-infinite cohomology of the
loop algebra has a structure, which is analogous to the classical structure of
the de Rham cohomology in K\"ahler geometry.

</DOC>
<DOC>
<DOCNO> 13420 </DOCNO>
Soft Phonon Anomalies in Relaxor Ferroelectrics


  A review is given of the phonon anomalies, which have been termed
``waterfalls,'' that were recently discovered through a series of neutron
inelastic scattering measurements on the lead-oxide relaxor systems PZN-xPT,
PMN, and PZN. We discuss a simple coupled-mode model that has been used
successfully to describe the basic features of the waterfall, and which relates
this unusual feature to the presence of polar micro-regions.

</DOC>
<DOC>
<DOCNO> 151452 </DOCNO>
Yang-Mills Duality and the Generation Puzzle


  The fermion generation puzzle has survived into this century as one of the
great mysteries in particle physics. We consider here a possible solution
within the Standard Model framework based on a nonabelian generalization of
electric-magnetic duality. First, by constructing in loop space a nonabelian
generalization of the abelian dual transform (Hodge *), one finds that a
``magnetic'' symmetry exists also in classical Yang-Mills theory dual to the
original (``electric'') gauge symmetry. Secondly, from a result of 't Hooft's,
one obtains that for confined colour SU(3), the dual symmetry
$\widetilde{SU}(3)$ is spontaneously broken and can play the role of the
``horizontal symmetry'' for generations. Thirdly, such an identification not
only offers an explanation why there should be three and apparently only three
generations of fermions with the remarkable mass and mixing patterns seen in
experiment, but allows even a calculation of the relevant parameters giving
very sensible results. Other testible predictions follow ranging from rare
hadron decays to cosmic ray air showers.

</DOC>
<DOC>
<DOCNO> 8971 </DOCNO>
Theory for two-photon photoemission: transport and temperature effects


  Using a theory which treats on equal footing transport of excited electrons
and electron-phonon scattering, we are able to explain the temperature
dependence of the relaxation time in Cu as recently observed by Petek, Nagano,
and Ogawa. We show that the unexpected increase of the relaxation time with
temperature results from the drastic change of the electron motion due to the
efficiency of electron-phonon scattering: the transport is ballistic at low
temperature and gets diffusive at room temperature. Finally, our theory also
reproduces the experimental measurements of the two-photon photoemission (2PPE)
intensity as a function of the pump-probe delay.

</DOC>
<DOC>
<DOCNO> 71413 </DOCNO>
Deconfinement Through Chiral Transition In 2 Flavour QCD


  We propose that in QCD with dynamical quarks, colour deconfinement occurs
when an external field induced by the chiral condensate strongly aligns the
Polyakov loop. This effect sets in at the chiral symmetry restoration
temperature $T_{\chi}$ and thus makes deconfinement and chiral symmetry
restoration coincide. The predicted singular behavior of Polyakov loop
susceptibilities at $T_{\chi}$ is shown to be supported by finite temperature
lattice calculations.

</DOC>
<DOC>
<DOCNO> 152393 </DOCNO>
On the Beta Function for Anisotropic Current Interactions in 2D


  By making use of current-algebra Ward identities we study renormalization of
general anisotropic current-current interactions in 2D. We obtain a set of
algebraic conditions that ensure the renormalizability of the theory to all
orders. In a certain minimal prescription we compute the beta function to all
orders.

</DOC>
<DOC>
<DOCNO> 116994 </DOCNO>
Comparisons Of Equivalent Circuit Predictions With Measurements For


  In fabricating the first X-Band RDDS (Rounded Damped Detuned Structure)
accelerator structure, microwave measurements are made on short groups of discs
prior to bonding the discs of the entire structure. The design dispersion
curves are compared with the frequency measurements. The theory utilised is
based on a circuit model adapted to a short stack of slowly varying non-uniform
discs. The model reveals the nature of the modes in the structure and may also
be used to refit the experimental data to the parameters in a model of the
wakefield given earlier [1]. This method allows a more faithful determination
of the wakefield that a beam will experience as it traverses the structure.
Results obtained on the frequencies are compared to the original design.
  [1] R.M.Jones, et al, EPAC96 (also SLAC-PUB-7187)

</DOC>
<DOC>
<DOCNO> 8280 </DOCNO>
Reactive Hall response


  The zero temperature Hall constant R_H, described by reactive
(nondissipative) conductivities, is analyzed within linear response theory. It
is found that in a certain limit, R_H is directly related to the density
dependence of the Drude weight implying a simple picture for the change of sign
of charge carriers in the vicinity of a Mott-Hubbard transition. This novel
formulation is applied to the calculation of R_H in quasi-one dimensional and
ladder prototype interacting electron systems.

</DOC>
<DOC>
<DOCNO> 117785 </DOCNO>
Chi-Variable-Speed-of-Light Cosmologies


  Variable-Speed-of-Light (VSL) cosmologies are currently attracting much
interest as a possible alternative to cosmological inflation. We discuss the
fundamental geometrodynamic aspects of VSL cosmologies, and provide several
alternative implementations. These implementations provide a large class of VSL
cosmologies that pass the zeroth-order consistency tests of being compatible
with both classical Einstein gravity and low-energy particle physics. While
they solve the ``kinematic'' puzzles as well as inflation does, VSL cosmologies
typically do not solve the flatness problem since in their purest form no
violation of the strong energy condition occurs. Nevertheless, these models are
easy to unify with inflation.

</DOC>
<DOC>
<DOCNO> 71399 </DOCNO>
Observational Approaches to the Topology of the Universe


  Many different and complementary strategies for translating the basic
principle of multiple topological imaging into observational analysis are now
available, both for three-dimensional and two-dimensional catalogues.

</DOC>
<DOC>
<DOCNO> 170643 </DOCNO>
Introduction to quantum information theory


  This is an expanded and revised text for a fifteen minute talk given at the
University of Queensland Physics Camp, September 2000. The focus is on the
goals and motivations for studying quantum information theory, rather than on
technical results.

</DOC>
<DOC>
<DOCNO> 121755 </DOCNO>
Temperature of the central stars of planetary nebulae and the effect of


  The effect of the nebula optical depth on the determination of the
temperature (T*) of the central stars in planetary nebulae is discussed. Based
on photoionization models for planetary nebulae with different optical depths,
we show, quantitatively, that the details of the distribution of the H and He
II Zanstra temperatures are mainly explained by an optical depth effect; in
particular, that the discrepancy is larger for low stellar temperatures. The
results also show that for high stellar temperatures the He II Zanstra
temperature underestimates the stellar temperature, even for high optical
depths. The stellar temperature, as well as the optical depth, can be obtained
from a Zanstra temperature ratio (ZR) plot ZR = Tz(He II)/Tz(H) versus Tz(He
II). The effects of departures from a blackbody spectrum, as well as of the He
abundance in the nebulae, are also discussed. For nebulae of very low optical
depth and/or high stellar temperature the distribution ZR versus Tz(He II) only
provides lower limits for T*. In order to obtain better values for the optical
depth and T*, we propose the use of the line intensity ratio He II/He I versus
Tz(He II) diagram.

</DOC>
<DOC>
<DOCNO> 170074 </DOCNO>
Recycling of quantum information: Multiple observations of quantum


  How much information about the original state preparation can be extracted
from a quantum system which already has been measured? That is, how many
independent (non-communicating) observers can measure the quantum system
sequentially and give a nontrivial estimation of the original unknown state? We
investigate these questions and we show from a simple example that quantum
information is not entirely lost as a result of the measurement-induced
collapse of the quantum state, and that an infinite number of independent
observers who have no prior knowledge about the initial state can gain a
partial information about the original preparation of the quantum system.

</DOC>
<DOC>
<DOCNO> 9441 </DOCNO>
The quantum conductance of ballistic microconstrictions in metals with


  It is shown that the conductance $G$ of the quantum microconstriction in the
metal with an opened Fermi surface as a function of the contact diameter
undergoes the jumps $e^{2}/h$ of the opposite sign. The negative jumps is the
result of the limitation of the energy of the electron motion along the
direction, in which the Fermi surface is opened. The point contact spectrum
$dG/dV$ of such constriction has additional peaks at the bias $eV$ when the
maximal energy $\epsilon_{\max}$ of the quantum subband is equal to the
energies $\epsilon_{F}\pm \frac{eV}{2}$ ($\epsilon_{F}$ is the Fermi energy).

</DOC>
<DOC>
<DOCNO> 102139 </DOCNO>
Abelian varieties over finite fields with a specified characteristic


  We estimate the fraction of isogeny classes of abelian varieties over a
finite field which have a given characteristic polynomial P(T) modulo l. As an
application we find the proportion of isogeny classes of abelian varieties with
a rational point of order l.

</DOC>
<DOC>
<DOCNO> 83173 </DOCNO>
Differential Invariants under Gamma Correction


  This paper presents invariants under gamma correction and similarity
transformations. The invariants are local features based on differentials which
are implemented using derivatives of the Gaussian. The use of the proposed
invariant representation is shown to yield improved correlation results in a
template matching scenario.

</DOC>
<DOC>
<DOCNO> 178904 </DOCNO>
Treatment of pairing correlations in nuclei close to drip lines


  We discuss the HFB equations in coordinate representation,a suitable method
for handling the full effects of the continuous quasiparticle spectrum. We show
how the continuum HFB equations can be solved with the correct asymptotic
conditions instead of the discretization conditions which are commonly used in
the literature. The continuum HFB method is illustrated with a model where the
mean field and pairing field have simple forms. The relationship with the
continuum Hartree-Fock-BCS (HF-BCS) approximation is also discussed. Realistic
HFB and HF-BCS calculations based on Skyrme interactions are compared for the
case of a neutron-rich nucleus.

</DOC>
<DOC>
<DOCNO> 152615 </DOCNO>
Solitonic fullerene structures in light atomic nuclei


  The Skyrme model is a classical field theory which has topological soliton
solutions. These solitons are candidates for describing nuclei, with an
identification between the numbers of solitons and nucleons. We have computed
numerically, using two different minimization algorithms, minimum energy
configurations for up to 22 solitons. We find, remarkably, that the solutions
for seven or more solitons have nucleon density isosurfaces in the form of
polyhedra made of hexagons and pentagons. Precisely these structures arise,
though at the much larger molecular scale, in the chemistry of carbon shells,
where they are known as fullerenes.

</DOC>
<DOC>
<DOCNO> 9331 </DOCNO>
Interaction-Induced Magnetization of the Two-Dimensional Electron Gas


  We consider the contribution of electron-electron interactions to the orbital
magnetization of a two-dimensional electron gas, focusing on the ballistic
limit in the regime of negligible Landau-level spacing. This regime can be
described by combining diagrammatic perturbation theory with semiclassical
techniques. At sufficiently low temperatures, the interaction-induced
magnetization overwhelms the Landau and Pauli contributions. Curiously, the
interaction-induced magnetization is third-order in the (renormalized) Coulomb
interaction. We give a simple interpretation of this effect in terms of
classical paths using a renormalization argument: a polygon must have at least
three sides in order to enclose area. To leading order in the renormalized
interaction, the renormalization argument gives exactly the same result as the
full treatment.

</DOC>
<DOC>
<DOCNO> 117623 </DOCNO>
Detection of an X-Ray Hot Region in the Virgo Cluster of Galaxies with


  Based on mapping observations with ASCA, an unusual hot region with a spatial
extent of 1 square degree was discovered between M87 and M49 at a center
coordinate of R. A. = 12h 27m 36s and Dec. = $9^\circ18'$ (J2000). The X-ray
emission from the region has a 2-10 keV flux of $1 \times 10^{-11}$ ergs
s$^{-1}$ cm$^{-2}$ and a temperature of $kT \gtrsim 4$ keV, which is
significantly higher than that in the surrounding medium of $\sim 2$ keV. The
internal thermal energy in the hot region is estimated to be $V n k T \sim
10^{60}$ ergs with a gas density of $\sim 10^{-4}$ cm$^{-3}$. A power-law
spectrum with a photon index $1.7-2.3$ is also allowed by the data. The hot
region suggests there is an energy input due to a shock which is probably
caused by the motion of the gas associated with M49, infalling toward the M87
cluster with a velocity $\gtrsim 1000$ km s$^{-1}$.

</DOC>
<DOC>
<DOCNO> 39898 </DOCNO>
Current status of K2K long-baseline neutrino-oscillation experiment


  The K2K (KEK to Kamioka) long-baseline neutrino-oscillation experiment was
successfully started in early 1999. A total intensity of 7.20 x 10^18 protons
on target, which is about 7% of the goal of the experiment, was accumulated in
39.4 days of data-taking in 1999. We obtained 3 neutrino events in the fiducial
volume of the Super-Kamiokande detector, whereas the expectation based on
observations in the front detectors is 12.3 +1.7/-1.9. An analysis of
oscillation searches from the view points of absolute event numbers, distortion
of neutrino energy spectrum, and nu_e/nu_mu ratio is in progress.

</DOC>
<DOC>
<DOCNO> 169636 </DOCNO>
Covariance Systems on the Projective Line


  We study the positive-operator-valued measures on the projective real line
covariant with respect to the projective group, assuming that the energy is a
positive operator. This problem is similar to the more complicated problem of
finding the positive-operator-valued measures on the compactified Minkowski
space-time covariant with respect to the conformal group. It also describes a
time-of-arrival observable for a free particle covariant with respect to linear
canonical transformations.

</DOC>
<DOC>
<DOCNO> 71328 </DOCNO>
Minimalistic Neutrino Mass Model


  We consider the simplest model which solves the solar and atmospheric
neutrino puzzles, in the sense that it contains the smallest amount of beyond
the Standard Model ingredients. The solar neutrino data is accounted for by
Planck-mass effects while the atmospheric neutrino anomaly is due to the
existence of a single right-handed neutrino at an intermediate mass scale
between 10^9 GeV and 10^14 GeV. Even though the neutrino mixing angles are not
exactly predicted, they can be naturally large, which agrees well with the
current experimental situation. Furthermore, the amount of lepton asymmetry
produced in the early universe by the decay of the right-handed neutrino is
very predictive and may be enough to explain the current baryon-to-photon ratio
if the right-handed neutrinos are produced out of thermal equilibrium. One
definitive test for the model is the search for anomalous seasonal effects at
Borexino.

</DOC>
<DOC>
<DOCNO> 151078 </DOCNO>
Triality of Majorana-Weyl Spacetimes with Different Signatures


  Higher dimensional Majorana-Weyl spacetimes present space-time dualities
which are induced by the Spin(8) triality automorphisms. This corresponds to a
very fundamental property of the supersymmetry in higher dimensions, i.e. that
any given theory can be formulated in different signatures all interconnected
by the S_3 permutation group.

</DOC>
<DOC>
<DOCNO> 8685 </DOCNO>
Spin transport in interacting quantum wires and carbon nanotubes


  We present a general formulation of spin-dependent transport through a clean
one-dimensional interacting quantum wire or carbon nanotube, connected to
non-collinear ferromagnets via tunnel junctions. We show that the low energy
description of each junction is given by a conformally-invariant boundary
condition representing *exchange coupling*, in addition to a pair of electron
tunneling operators. The effects of the exchange coupling are strongly enhanced
by interactions, leading to a dramatic suppression of spin accumulation. This
is a direct signature of spin-charge separation in a Luttinger liquid.
Furthermore, we demonstrate that magnetic polarization can lead to oscillations
in the non-linear current-voltage relation. This phenomena is a surprising
purely nonequilibrium effect due to backscattering interactions, which are thus
dangerously marginally irrelevant in the repulsively-interacting Luttinger
liquid.

</DOC>
<DOC>
<DOCNO> 11457 </DOCNO>
Magnetotransport of coupled electron-holes


  The carriers in InAs-GaSb double quantum wells are hybrid ``electron-holes''.
We study the magnetotransport properties of such particles using a
two-component Keldysh technique, which results in a semi-analytic expression
for the small-field current. We show that zero temperature current can be large
even when the Fermi energy lies within the hybridization gap, a result which
cannot be understood within a semiclassical (Boltzmann) approach. Magnetic
field dependence of the conductance is also affected significantly by the
hybridization of electrons and holes.

</DOC>
<DOC>
<DOCNO> 118842 </DOCNO>
Multifrequency studies of Gamma-Ray bursts: towards the understanding of


  GRBs have remained a puzzle for many high-energy astrophysicists since their
discovery in 1967. With the advent of the X-ray satellites BeppoSAX and
RossiXTE, it has been possible to carry out deep multi-wavelength observations
of the counterparts associated with the GRBs just within a few hours of
occurence, thanks to the observation of the fading X-ray emission that follows
the more energetic gamma-ray photons once the GRB event has ended. The fact
that this emission (the afterglow) extends at longer wavelengths, has led to
the discovery of the first optical/IR/radio counterparts in 1997-99, greatly
improving our understanding of these sources. Now it is widely accepted that
GRBs originate at cosmological distances. The observed afterglow satisfies the
predictions of the "standard" relativistic fireball model, and the central
engines that power these extraordinary events are thought to be the collapse of
massive stars or the merging of compact objects.

</DOC>
<DOC>
<DOCNO> 100316 </DOCNO>
Minimal Models for Non-Free Circle Actions


  Let $\Phi \colon \sbat \times M \to M$ be a smooth action of the unit circle
$ \sbat$ on a manifold $M$. In this work, we compute the minimal model of $M$
in terms of the orbit space $B$ and the fixed point set $F\subset B$, as a
dg-module over the Sullivan's minimal model of $B$.

</DOC>
<DOC>
<DOCNO> 151862 </DOCNO>
Superstrings in AdS in light cone gauge


  We discuss light-cone gauge description of type IIB Green-Schwarz superstring
in AdS_5 x S^5 with a hope to make progress towards understanding spectrum of
this theory. As in flat space, fixing light cone gauge consists of two steps:
(i) fixing kappa symmetry in such a way that the fermionic part of the action
does not depend on x^-; (ii) fixing 2-d reparametrizations by x^+ = tau and a
condition on 2-d metric. In curved AdS space the latter cannot be the standard
conformal gauge and breaks manifest 2-d Lorentz invariance. It is natural,
therefore, to work in phase-space framework, imposing the GGRT gauge conditions
x^+= tau, P^+ =const. We obtain the resulting light cone superstring
Hamiltonian. This is a review of hep-th/0007036 and hep-th/0009171.

</DOC>
<DOC>
<DOCNO> 121592 </DOCNO>
Probing High-Redshift Disks with Damped Lyman Alpha Systems


  Evidence is presented that the damped Lyman alpha absorption systems are the
high-redshift (z > 3) progenitors of galaxy disks. I discuss kinematic evidence
that the damped Lyman Alpha systems are rotating disks. I also discuss
implications of the lack of metal-poor damped Lyman alpha systems with line
width Delta v > 100 {\kms}. I then present new evidence stemming from
correlations between element-abundance ratios and [Fe/H], which connects damped
systems to the thick stellar disk of the Galaxy. I discuss the connections
between damped Lyman alpha systems and Lyman break galaxies, and how [CII] 158
micron emission from damped Lyman alpha systems discriminates among competing
theories of galaxy formation. ~

</DOC>
<DOC>
<DOCNO> 80603 </DOCNO>
Fast methods for computing the Neuberger Operator


  I describe a Lanczos method to compute the Neuberger Operator and a multigrid
algorithm for its inversion.

</DOC>
<DOC>
<DOCNO> 150364 </DOCNO>
BRST Formalism and Zero Locus Reduction


  In the BRST quantization of gauge theories, the zero locus $Z_Q$ of the BRST
differential $Q$ carries an (anti)bracket whose parity is opposite to that of
the fundamental bracket. We show that the on-shell BFV/BV gauge symmetries are
in a 1:1 correspondence with Hamiltonian vector fields on $Z_Q$, and
observables of the BRST theory are in a 1:1 correspondence with characteristic
functions of the bracket on $Z_Q$. By reduction to the zero locus, we obtain
relations between bracket operations and differentials arising in different
complexes (the Gerstenhaber, Schouten, Berezin-Kirillov, and Sklyanin
brackets); the equation ensuring the existence of a nilpotent vector field on
the reduced manifold can be the classical Yang-Baxter equation. We also
generalize our constructions to the bi-QP-manifolds which from the BRST theory
viewpoint corresponds to the BRST-anti-BRST-symmetric quantization.

</DOC>
<DOC>
<DOCNO> 101145 </DOCNO>
The Gromov norm and foliations


  We define a norm on the homology of a foliated manifold, which refines and
majorizes the usual Gromov norm on homology. This norm depends in an upper
semi-continuous way on the underlying foliation, in the geometric topology, and
can therefore be used to study the question of which foliations arise as
geometric limits of isotopy classes of other foliations. We show that this norm
is non-trivial -- i.e. it distinguishes certain taut foliations of a given
hyperbolic 3-manifold. In fact, modulo some standard conjectures, this norm
should precisely detect amongst taut foliations of closed atoroidal
3-manifolds, those whose universal covers branch in both directions.
  A homotopy-theoretic refinement gives even more information in certain cases;
in particular, we show that a taut foliation whose leaf space in the universal
cover branches in at most one direction cannot be the geometric limit of a
sequence of isotopies of a fixed taut foliation whose leaf space in the
universal cover branches in both directions. Our technology also lets us
produce examples of taut foliations which cannot be made transverse to certain
geodesic triangulations of hyperbolic 3-manifolds, even after passing to a
finite cover.
  Finally, our norm can be extended to actions of fundamental groups of
manifolds on order trees, where it has similar upper semi-continuity
properties.

</DOC>
<DOC>
<DOCNO> 70624 </DOCNO>
Stochastic backgrounds of gravitational waves


  We review the motivations for the search of stochastic backgrounds of
gravitational waves and we compare the experimental sensitivities that can be
reached in the near future with the existing bounds and with the theoretical
predictions.

</DOC>
<DOC>
<DOCNO> 67760 </DOCNO>
Chiral Expansion at Energy Scale of $\rho$-Mass


  We study chiral expansion at $m_\rho$-scale in framework of chiral
constituent quark model. The lowest vector meson resonsances are treated as
composited fields of constituent quarks. We illustrate that, at energy scale of
$\rho$-meson mass, the chiral expansion expansion converges slowly. Therefore,
it is possible to construct a well-defined chiral effective field theory at
this energy scale, but high order correction of chiral expansion must be
included simultanously. The one-loop correction of pseudoscalar mesons is also
studied systematically. The unitarity of the model is examined and Breit-Wigner
formula for $\rho$-meson is obtained. The prediction on on-shell
$\rho\to\pi\pi$ and $\rho\to e^+e^-$ decays agree with data very well.

</DOC>
<DOC>
<DOCNO> 117108 </DOCNO>
Analysis of Causality Issue in Near-field Superluminally Propagating


  A simple relativistic analysis is presented which shows that near-field
superluminal longitudinal electric signals generated by an electric dipole
cannot be used to violate Einstein causality by using the relativistic "sync
shift" effect. The analysis shows that because a signal has some time extent
(i.e. after a signal is initiated one must waitat least one period for the
frequency and amplitude information to be determined), an electric dipole can
be used to transmit a signal backward in time, but not before the same signal
was initiated, thereby prohibiting a user from changing the signal that was
transmitted. The result is also shown to apply to the superluminal near-field
gravitational fields generated by an oscillating mass.

</DOC>
<DOC>
<DOCNO> 80769 </DOCNO>
An Almost Perfect Lattice Action for infrared QCD


  A block-spin transformation on the dual lattice leads us to an almost perfect
lattice action for monopoles and strings in QCD. The perfect operator for a
static quark potential is fixed when we compare the above action with the
perfect action obtained analytically after infinite-step block-spin
transformations in a simple case. The continuum rotational invariance is
restored and the physical value of the string tension is reproduced fairly
well. Gauge independence of the abelian and the monopole scenario is discussed.

</DOC>
<DOC>
<DOCNO> 80738 </DOCNO>
Vortices, monopoles and confinement


  We construct the creation operator of a vortex using the methods developed
for monopoles. The vacuum expectation value of this operator is interpreted as
a disorder parameter describing vortex condensation and is studied numerically
on a lattice in SU(2) gauge theory. The result is that vortices behave in the
vacuum in a similar way to monopoles. The disorder parameter is different from
zero in the confined phase, and vanishes at the deconfining phase transition.
We discuss this behaviour in terms of symmetry. Correlation functions of the
vortex creation operator at zero temperature are also investigated. A
comparison is made with related results by other groups.

</DOC>
<DOC>
<DOCNO> 9298 </DOCNO>
Statistical mechanics of money: How saving propensity affects its


  We consider a simple model of a closed economic system where the total money
is conserved and the number of economic agents is fixed. In analogy to
statistical systems in equilibrium, money and the average money per economic
agent are equivalent to energy and temperature, respectively. We investigate
the effect of the saving propensity of the agents on the stationary or
equilibrium money distribution.The equilibrium probablity distribution of money
becomes the usual Gibb's distribution, characteristic of non-interacting
agents, when the agents do not save. However with saving, even for local or
individual self-interest, the dynamics become cooperative and the resulting
asymmetric Gaussian-like stationary distribution acquires global ordering
properties. Intriguing singularities are observed in the stationary money
distribution in the market, as function of the ``marginal saving propensity''
of the agents.

</DOC>
<DOC>
<DOCNO> 10437 </DOCNO>
Directed Percolation has Colors and Flavors


  A model of directed percolation processes with colors and flavors that is
equivalent to a population model with many species near their extinction
thresholds is presented. We use renormalized field theory and demonstrate that
all renormalizations needed for the calculation of the universal scaling
behavior near the multicritical point can be gained from the one-species Gribov
process (Reggeon field theory). In addition this universal model shows an
instability that generically leads to a total asymmetry between each pair of
species of a cooperative society, and finally to unidirectionality of the
interspecies couplings. It is shown that in general the universal multicritical
properties of unidirectionally coupled directed percolation processes with
linear coupling can also be described by the model. Consequently the crossover
exponent describing the scaling of the linear coupling parameters is given by
$\Phi =1$ to all orders of the perturbation expansion. As an example of
unidirectionally coupled directed percolation, we discuss the population
dynamics of the tournaments of three colors.

</DOC>
<DOC>
<DOCNO> 122502 </DOCNO>
A Hipparcos study of the Hyades open cluster: Improved colour-absolute


  Hipparcos parallaxes fix distances to individual stars in the Hyades cluster
with an accuracy of 6%. We use the Hipparcos (and Tycho-2) proper motions,
which have a larger relative precision than the trigonometric parallaxes, to
derive ~3 times more precise distance estimates, by assuming that all members
share the same space motion. The improved parallaxes as a set are statistically
consistent with the Hipparcos parallaxes. The new parallaxes confirm that the
Hipparcos measurements are correlated on small angular scales, consistent with
the limits specified in the Hipparcos Catalogue, though with significantly
smaller `amplitudes' than claimed by Narayanan & Gould.
   The colour-absolute magnitude diagram of the cluster based on the new paral-
laxes shows a well-defined main sequence with two gaps/turn-offs. These
features provide the first direct observational support of Boehm-Vitense's
prediction that (the onset of) surface convection in stars affects their B-V
colours. We present and discuss the theoretical HRD for an objectively defined
set of 88 high-fidelity members of the cluster as well as the delta Scuti star
theta^2 Tau, the giants delta^1, theta^1, epsilon, and gamma Tau, and the white
dwarfs V471 Tau and HD 27483 (all of which are also members). The precision
with which the new parallaxes place individual Hyades members in the Hertz-
sprung-Russell diagram is limited by (systematic) uncertainties related to the
transformations from observed colours and absolute magnitudes to effective
temperatures and luminosities. The new parallaxes provide stringent constraints
on the calibration of such transformations when combined with theoretical
stellar evolutionary modelling, tailored to the chemical composition and age of
the Hyades, over the large stellar mass range probed by Hipparcos.

</DOC>
<DOC>
<DOCNO> 122607 </DOCNO>
New Observations of Extra-Disk Molecular Gas in Interacting Galaxy


  We present new CO (1 - 0) observations of eleven extragalactic tails and
bridges in nine interacting galaxy systems, almost doubling the number of such
features with sensitive CO measurements. Eight of these eleven features were
undetected in CO to very low CO/HI limits, with the most extreme case being the
NGC 7714/5 bridge. This bridge contains luminous H II regions and has a very
high HI column density (1.6 X 10^21 cm^-2 in the 55" CO beam), yet was
undetected in CO to rms T(R)* = 2.4 mK. The HI column density is higher than
standard H2 and CO self-shielding limits for solar-metallicity gas, suggesting
that the gas in this bridge is metal-poor and has an enhanced N(H2)/I(CO) ratio
compared to the Galactic value. Only one of the eleven features in our sample
was unambiguously detected in CO, a luminous HI-rich star formation region near
an optical tail in the compact group Stephan's Quintet. We detect CO at two
widely separated velocities in this feature, at ~6000 km/s and ~6700 km/s. Both
of these components have HI and H-alpha counterparts. These velocities
correspond to those of galaxies in the group, suggesting that this gas is
material that has been removed from two galaxies in the group. The
CO/HI/H-alpha ratios for both components are similar to global values for
spiral galaxies.

</DOC>
<DOC>
<DOCNO> 10323 </DOCNO>
Pseudogap in Bi2Sr2CaCu2O8+d studied by measuring anisotropic


  We find in the Bi2Sr2CaCu2O8+d system that the characteristic temperatures
T*_chi [below which the uniform susceptibilities chi_ab(T) (H perpendicular to
c) and chi_c(T)(H parallel to c) decrease] and T*_rho_c (below which the
out-of-plane resistivity rho_c(T) shows typical upturn) coincide for all doping
levels. We attribute the T dependence of chi's and rho_c to the anomalous
(pseudogapped) density-of-states (DOS) in high-Tc cuprates. Furthermore, the
anisotropy in the T dependence of chi's is universal, i.e., chi_c proportional
to1.6chi_ab, showing that there is only a single T-dependent component in the
chi's. This implies that the Curie-like behavior (dchi/dT<0) observed in
overdoped samples is also caused by a DOS effect.

</DOC>
<DOC>
<DOCNO> 99758 </DOCNO>
Some examples of aspherical symplectic four-manifolds


  The paper was withdrawn due to a gap in the proof of Lemma 3.

</DOC>
<DOC>
<DOCNO> 12493 </DOCNO>
The one-dimensional contact process: duality and renormalisation


  We study the one-dimensional contact process in its quantum version using a
recently proposed real space renormalisation technique for stochastic
many-particle systems. Exploiting the duality and other properties of the
model, we can apply the method for cells with up to 37 sites. After suitable
extrapolation, we obtain exponent estimates which are comparable in accuracy
with the best known in the literature.

</DOC>
<DOC>
<DOCNO> 69816 </DOCNO>
Electroweak Sudakov logarithms in the Coulomb gauge


  We describe a formalism for calculating electroweak Sudakov logarithms in the
Coulomb gauge. This formalism is applicable to arbitrary electroweak processes.
For illustration we focus on the specific reactions e^+e^- -> f \bar{f} and
e^+e^- -> W_T^+W_T^-, W_L^+W_L^-, which contain all the salient details of
dealing with the various types of particles. We discuss an explicit two-loop
calculation and have a critical look at the (non-)exponentiation and
factorisation properties of the Sudakov logarithms in the Standard Model.

</DOC>
<DOC>
<DOCNO> 152625 </DOCNO>
Does the Higgs mechanism favour electron-electron bound states in


  The low-energy electron-electron scattering potential is derived and
discussed for the Maxwell-Chern-Simons model coupled to QED_3 with spontaneous
symmetry breaking. One shows that the Higgs mechanism might favour
electron-electron bound states.

</DOC>
<DOC>
<DOCNO> 8382 </DOCNO>
Fermi systems with long scattering lengths


  Ground state energies and superfluid gaps are calculated for degenerate Fermi
systems interacting via long attractive scattering lengths such as cold atomic
gases, neutron and nuclear matter. In the intermediate region of densities,
where the interparticle spacing $(\sim 1/k_F)$ is longer than the range of the
interaction but shorter than the scattering length, the superfluid gaps and the
energy per particle are found to be proportional to the Fermi energy and thus
differs from the dilute and high density limits. The attractive potential
increase linearly with the spin-isospin or hyperspin statistical factor such
that, e.g., symmetric nuclear matter undergoes spinodal decomposition and
collapses whereas neutron matter and Fermionic atomic gases with two hyperspin
states are mechanically stable in the intermediate density region. The regions
of spinodal instabilities in the resulting phase diagram are reduced and do not
prevent a superfluid transition.

</DOC>
<DOC>
<DOCNO> 68079 </DOCNO>
Some low energy effects of a light stabilized radion in the


  In this paper we study some low energy effects of a light stabilized radion
in the Randall-Sundrum scenario. We find that the NLC 500 with its projected
precision level will be able to probe the radion contribution to the anomalous
magnetic moment and electric quadrupole moment of W boson for values of radion
vev up to 500 Gev. On the other hand the BNL experiment E821 will be able to
test the radion contribution to $a_{\mu}$ for 1 Tev radion vev and $m_{\phi}\le
m_{\mu}$. We have also shown that the higgs-radion mixing induces a 2.6%
correction in the WWh coupling. Finally by comparing the radionstrahlung with
the higgsstrahlung process we have found that the LEPI bound on the higgs mass
based on $Z\to hl\bar{l}$ decay mode suggests a lower bound of about 35 Gev on
the radion mass.

</DOC>
<DOC>
<DOCNO> 10974 </DOCNO>
Observation of Persistent Currents in Mesoscopic Connected Rings


  We report measurements of the low temperature magnetic response of a line of
16 GaAs/GaAlAs \emph{connected} mesoscopic rings whose total length is much
larger than $l_{\phi}$. Using an on-chip micro-\textsc{squid} technology, we
have measured a periodic response, with period $h/e$, corresponding to
persistent currents in the rings of typical amplitude $0.40\pm 0.08 nA$ per
ring. Direct comparison with measurements on the same rings but \emph{isolated}
is presented.

</DOC>
<DOC>
<DOCNO> 121017 </DOCNO>
Damped Lyman alpha systems at z=0.68 and z=1.15 towards HE 1122-1649 and


  Detailed analysis of the spectral lines from two low redshift damped Lyman
alpha absorbers (DLA) confirms that they are a heterogeneous population. Both
systems have low metal abundances of approximately 0.05 to 0.1 solar. The
abundance pattern of the DLA at z=1.15 towards HE 0515-4414 shows dust
depletion comparable to that found in our Galaxy, while the system at z=0.68
towards HE 1122-1649 shows abundance ratios resembling metal-poor halo stars
with no dust depletion, for a comparable HI column. Constraints for N/Fe and
N/Si also hint at z=0.68 DLA as a galaxy with recent star formation. The trend
of increasing CI/HI with decreasing z is discussed. Only weak absorption from
highly-ionized species associated with the DLA at moderate z have been detected
and it probably originates in regions distinct from the low ionization gas. The
low-ion profiles show very complex structures and are too large to be explained
by the rotation of a disk: the system at z=0.68 spans over approximately 300
km/s and the z=1.15 DLA presents substructure over more than 700 km/s, the
largest velocity extent found up to date for a DLA.

</DOC>
<DOC>
<DOCNO> 178809 </DOCNO>
Dibaryon Systems In SU(3) Chira Quark Model


  The possible candidates of $S-$wave dibaryons with various strange numbers
are studied under the chiral SU(3) quark model. It is shown that there are
three types of baryon-baryon bound states. The states of the first type are
called deuteron-like states. If chiral fields can provide enough attraction
between interacting baryons, these systems, such as $[\Xi\Omega -
\Xi^{*}\Omega]_{(1,1/2)}$, $[\Xi\Xi]_{(0,1)}$, $[N \Omega]_{(2,1/2)}$ would be
weakly bound. The states of the second type such as $[\Sigma^{*}
\Delta]_{(0,5/2)}$, $[\Sigma^{*} \Delta]_{(3,1/2)}$, $[\Delta\Delta]_{(0,3)}$
and $[\Delta\Delta]_{(3,0)}$ are named as $\Delta\Delta$-like states. Due to
the highly symmetric character in orbital space, these systems could be
relatively deeply bound, but the strong decay modes of composed baryons cause
the widths of the states much broader. The states of the third type are
entitled as $\Omega\Omega$-like states. Due to the same symmetry character
shown in the systems of the second type and the only weak decay mode of
composed baryons, for instance in $[\Omega\Omega]_{(0,0)}$, or at most one
strong decay mode of composed baryons, for example in
$[\Xi^{*}\Omega]_{(0,1/2)}$, these states are deeply bound states with narrow
widths. The states of latter two types are most interesting new dibaryon states
and should be carefully investigated both theoretically and experimentally.

</DOC>
<DOC>
<DOCNO> 69817 </DOCNO>
Gluballs in the String Quark Model


  It is shown that the eigenstates of the quantized simplest closed (elliptic)
Nambu -- Goto string, called glueballs, have quantum numbers
I^Gj^{PC}=0^+j^{++}. Lightest glueballs have spins j=0,1 and 2 and the same
mass 1500 +/- 20 MeV. They correspond to f_0(1500), f_1(1510) and f_2(1565)-
mesons. Next glueballs have j=0,1,2,3,4 and the same mass 2610 +/- 20 MeV. The
slope of the glueball Regge trajectories is twice as small as for q\bar
q-mesons. The intersept of the leading glueball trajectory - the pomeron Regge
trajectory - is 1.07 +/- 0.03

</DOC>
<DOC>
<DOCNO> 122854 </DOCNO>
Pseudoparticle Multipole Method: A Simple Method to Implement


  In this letter we describe the pseudoparticle multipole method (P2M2), a new
method to express multipole expansion by a distribution of pseudoparticles. We
can use this distribution of particles to calculate high order terms in both
the Barnes-Hut treecode and FMM. The primary advantage of P2M2 is that it works
on GRAPE. GRAPE is a special-purpose hardware for the calculation of
gravitational force between particles. Although the treecode has been
implemented on GRAPE, we could handle terms only up to dipole, since GRAPE can
calculate forces from point-mass particles only. Thus the calculation cost
grows quickly when high accuracy is required. With P2M2, the multipole
expansion is expressed by particles, and thus GRAPE can calculate high order
terms. Using P2M2, we implemented an arbitrary-order treecode on GRAPE-4.
Timing result shows GRAPE-4 accelerates the calculation by a factor between 10
(for low accuracy) to 150 (for high accuracy). Even on general-purpose
programmable computers, our method offers the advantage that the mathematical
formulae and therefore the actual program is much simpler than that of the
direct implementation of multipole expansion.

</DOC>
<DOC>
<DOCNO> 122660 </DOCNO>
Modelling gaseous and stellar kinematics in the disc galaxies NGC 772,


  We present V-band surface photometry and major-axis kinematics of stars and
ionized gas of three early-type spiral galaxies, namely NGC 772, NGC 3898 and
NGC 7782. For each galaxy we present a self-consistent Jeans model for the
stellar kinematics, adopting the light distribution of bulge and disc derived
by means of a two-dimensional parametric photometric decomposition. This
allowed us to investigate the presence of non-circular gas motions, and derive
the mass distribution of luminous and dark matter in these objects.
  NGC 772 and NGC 7782 have apparently normal kinematics with the ionized gas
tracing the gravitational equilibrium circular speed. This is not true in the
innermost region (r < 8'') of NGC 3898 where the ionized gas is rotating more
slowly than the circular velocity predicted by dynamical modelling. This
phenomenon is common in the bulge-dominated galaxies for which dynamical
modelling enables us to make the direct comparison between the gas velocity and
the circular speed, and it poses questions about the reliability of galaxy mass
distributions derived by the direct decomposition of the observed ionized-gas
rotation curve into the contributions of luminous and dark matter.

</DOC>
<DOC>
<DOCNO> 68764 </DOCNO>
Neutrino Oscillations v.s. Leptogenesis in SO(10) Models


  We study the link between neutrino oscillations and leptogenesis in the
minimal framework assuming an SO(10) see-saw mechanism with 3 families. The
solar and atmospheric data then generically induce a large mass-hierarchy and a
small mixing between the lightest right-handed neutrinos, which fails to
produce sufficient lepton asymmetry by 5 orders of magnitudes at least. This
conclusion can only be evaded in the case of solar vacuum oscillations and for
a very specific value of the mixing sin^2(2\theta_e3)=0.1, which interestingly
lies at the boundary of the CHOOZ exclusion region, but should be accessible to
future long baseline experiments.

</DOC>
<DOC>
<DOCNO> 178743 </DOCNO>
Bound-Free Electron-Positron Pair Production in Relativistic Heavy Ion


  We study the bound-free electron-positron pair production in relativistic
heavy ion collisions to different bound states in a full Plane Wave Born
Approximation (PWBA) calculation. Exact Dirac wave functions are used for both
the bound electron and the free positron in the final states. Results for the
Relativistic Heavy Ion Collider RHIC as well as the forthcoming Large Hadron
Collider (LHC) are given. This process is one of the dominant beam loss
processes and can become critical for the operation with heavy ions. A simple
parameterization is given as well. We compare our results with calculations of
other groups.

</DOC>
<DOC>
<DOCNO> 40245 </DOCNO>
The Flavor and Spin Structure of Hyperons from Quark Fragmentation


  We systematically study the hadron longitudinal polarizations of the octet
baryons at large $z$ from quark fragmentations in $e^+e^-$-annihilation,
polarized charged lepton deep inelastic scattering (DIS) process, and neutrino
(antineutrino) DIS process, based on predictions of quark distributions for the
octet baryons in the SU(6) quark-spectator-diquark model and a perturbative QCD
based counting rule analysis. We show that the $e^+e^-$-annihilation and
polarized charged lepton DIS process are able to distinguish between the two
different predictions of the hyperon polarizations. We also find that the
neutrino/antineutrino DIS process is ideal in order to study both the valence
content of the hyperons and the antiquark to hyperon (quark to anti-hyperon)
fragmentations, which might be related to the sea content of hyperons.

</DOC>
<DOC>
<DOCNO> 119587 </DOCNO>
Doubling the number of Be/X-ray binaries in the SMC


  A correlation of X-ray source and Halpha emission-line object catalogues in
the Small Magellanic Cloud (SMC) shows that more than two thirds of the
optically identified Be stars in Be/X-ray binaries are found as emission-line
objects in the catalogues. On the basis of this result we propose up to 25
X-ray sources mainly from recent ROSAT catalogues as new Be/X-ray binaries and
give their likely optical counterparts. Also for the five yet unidentified
X-ray pulsars in the SMC we propose emission-line stars as counterparts. This
more than doubles the number of known high mass X-ray binary systems in this
nearby galaxy. The spatial distribution of the new candidates is similar to
that of the already identified Be/X-ray binaries with a strong concentration
along the SMC main body and some systems in the eastern wing. The new
candidates contribute mainly to the low-luminosity end of the X-ray luminosity
distribution of Be/X-ray binaries. A comparison with the luminosity
distribution in the Milky Way reveals no significant differences at the
high-luminosity end and the large number of low-luminosity systems in the SMC
suggests that many such systems may still be undetected in the Galaxy. The
overall ratio of known Be to OB supergiant X-ray binaries in the SMC is an
order of magnitude larger than in the Galaxy, however, might show spatial
variations. While in the eastern wing the ratio is comparable to that in the
Galaxy no supergiant X-ray binary is currently known in the main body of the
SMC. Possible explanations include a different star formation history over the
last ~15 My.

</DOC>
<DOC>
<DOCNO> 9980 </DOCNO>
Structure and relaxations in liquid and amorphous Selenium


  We report a molecular dynamics simulation of selenium, described by a
three-body interaction. The temperatures T_g and T_c and the structural
properties are in agreement with experiment. The mean nearest neighbor
coordination number is 2.1. A small pre-peak at about 1 AA^-1 can be explained
in terms of void correlations. In the intermediate self-scattering function,
i.e. the density fluctuation correlation, classical behavior, alpha- and
beta-regimes, is found. We also observe the plateau in the beta-regime below
T_g. In a second step, we investigated the heterogeneous and/or homogeneous
behavior of the relaxations. At both short and long times the relaxations are
homogeneous (or weakly heterogeneous). In the intermediate time scale, lowering
the temperature increases the heterogeneity. We connect these different domains
to the vibrational (ballistic), beta- and alpha-regimes. We have also shown
that the increase in heterogeneity can be understood in terms of relaxations.

</DOC>
<DOC>
<DOCNO> 12280 </DOCNO>
Topological Quenching of Spin Tunneling in Mn_12-acetate Molecules


  We investigate the topological quenching of spin tunneling in Mn_12-acetate
molecules with an applied magnetic field along the hard axis. The model
Hamiltonian describing this system has a fourth-order term due to the
tetragonal anisotropy. We treat this model using the discrete phase integral
formalism in which the Schrodinger equation corresponding to the Hamiltonian
becomes a nine-term recursion relation. We solve this recursion relation and
find that the tunnel splitting is quenched at certain values of the applied
field. We also present a qualitative treatment based on the instanton approach.

</DOC>
<DOC>
<DOCNO> 122963 </DOCNO>
A Preliminary Detection of Arcminute Scale Cosmic Microwave Background


  We have used the Berkeley-Illinois-Maryland-Association (BIMA) array
outfitted with sensitive cm-wave receivers to expand our search for arcminute
scale anisotropy of the Cosmic Microwave Background (CMB). The interferometer
was placed in a compact configuration toobtain high brightness sensitivity on
arcminute scales over its 6.6' FWHM field of view. The sensitivity of this
experiment to flat band power peaks at a multipole of l=5530 which corresponds
to an angular scale of ~2'. We present the analysis of a total of 470 hours of
on-source integration time on eleven independent fields which were selected
based on their low IR contrast and lack of bright radio sources. Applying a
Bayesian analysis to the visibility data, we find CMB anisotropy flat band
power Q_flat = 6.1(+2.8/-4.8) microKelvin at 68% confidence. The confidence of
a non- zero signal is 76% and we find an upper limit of Q_flat < 12.4
microKelvin at 95% confidence. We have supplemented our BIMA observations with
concurrent observations at 4.8 GHz with the VLA to search for and remove point
sources. We find the point sources make an insignificant contribution to the
observed anisotropy.

</DOC>
<DOC>
<DOCNO> 67744 </DOCNO>
Applications of QCD


  Talk given at XIXth International Symposium on Lepton and Photon Interactions
at High Energies (LP 99), Stanford, California, 9-14 August 1999.

</DOC>
<DOC>
<DOCNO> 99399 </DOCNO>
Weighted Traces on Algebras of Pseudo-Differential Operators and


  Using {\it weighted traces} which are linear functionals of the type $$A\to
tr^Q(A):=(tr(A Q^{-z})-z^{-1} tr(A Q^{-z}))_{z=0}$$ defined on the whole
algebra of (classical) pseudo-differential operators (P.D.O.s) and where $Q$ is
some positive invertible elliptic operator, we investigate the geometry of loop
groups in the light of the cohomology of pseudo-differential operators. We set
up a geometric framework to study a class of infinite dimensional manifolds in
which we recover some results on the geometry of loop groups, using again
weighted traces. Along the way, we investigate properties of extensions of the
Radul and Schwinger cocycles defined with the help of weighted traces.

</DOC>
<DOC>
<DOCNO> 72315 </DOCNO>
Single-spin asymmetry in DVCS: fragmentation region of polarised lepton


  For the kinematical region when a hard photon is emitted predominantly close
to the direction of motion of a longitudinally polarized initial electron and
relatively small momentum transfer to a proton we calculate the azimuthal
asymmetry of photon emission. It arises from the interference of the
Bethe-Heitler amplitude and those which are described by a heavy photon impact
factor. Azimuthal asymmetry does not decrease in the limit of infinite cms
energy. Lowest order expression for the impact factor of a heavy photon is
presented.

</DOC>
<DOC>
<DOCNO> 84726 </DOCNO>
No Black Hole Theorem in Three-Dimensional Gravity


  A common property of known black hole solutions in (2+1)-dimensional gravity
is that they require a negative cosmological constant. In this letter, it is
shown that a (2+1)-dimensional gravity theory which satisfies the dominant
energy condition forbids the existence of a black hole to explain the above
situation.

</DOC>
<DOC>
<DOCNO> 7753 </DOCNO>
A hybrid functional for the exchange-correlation kernel in


  A review of the approximations in any time-dependent density functional
calculation of excitation energies is given. The single-pole approximation for
the susceptibility is used to understand errors in popular approximations for
the exchange-correlation kernel. A new hybrid of exact exchange and adiabatic
local density approximation is proposed and tested on the He and Be atoms.

</DOC>
<DOC>
<DOCNO> 170481 </DOCNO>
Quantum Factor Graphs


  The natural Hilbert Space of quantum particles can implement
maximum-likelihood (ML) decoding of classical information. The 'Quantum Product
Algorithm' (QPA) is computed on a Factor Graph, where function nodes are
unitary matrix operations followed by appropriate quantum measurement. QPA is
like the Sum-Product Algorithm (SPA), but without summary, giving optimal
decode with exponentially finer detail than achievable using SPA. Graph cycles
have no effect on QPA performance. QPA must be repeated a number of times
before successful and the ML codeword is obtained only after repeated quantum
'experiments'. ML amplification improves decoding accuracy, and Distributed QPA
facilitates successful evolution.

</DOC>
<DOC>
<DOCNO> 10622 </DOCNO>
The structure relaxation of carbon nanotube


  A simple macroscopic continuum elasticity theory (CET) is used to calculate
the structure relaxation of single-wall carbon nanotube (SWNT), an analytic
formula is obtained. We also expand an atomic scale three-parameter empirical
model [ T. Lenosky {\emph et al.} Nature 355, 333(1992)] in order to correctly
describe the bond-length change effects. The structure relaxation of SWNT
expected by the model is good in agreement with our CET results, and very well
consistent with the previous calculation from a first principles local density
function approximation. Using the expanded Lenosky model, we calculate the
strain energy of bending tube. The obtained results are good in agreement with
the previous theoretical expectation. It shows the model may be a good simple
replacement of some more sophisticated methods on determining carbon networks
deformations.

</DOC>
<DOC>
<DOCNO> 13240 </DOCNO>
Random walks on fractals and stretched exponential relaxation


  Stretched exponential relaxation ($\exp{-(t/\tau)}^{\beta_K}$) is observed in
a large variety of systems but has not been explained so far. Studying random
walks on percolation clusters in curved spaces whose dimensions range from 2 to
7, we show that the relaxation is accurately a stretched exponential and is
directly connected to the fractal nature of these clusters. Thus we find that
in each dimension the decay exponent $\beta_K$ is related to well-known
exponents of the percolation theory in the corresponding flat space. We suggest
that the stretched exponential behavior observed in many complex systems
(polymers, colloids, glasses...) is due to the fractal character of their
configuration space.

</DOC>
<DOC>
<DOCNO> 70673 </DOCNO>
Non-topological solitons as nucleation sites for cosmological phase


  I consider quantum field theories that admit charged non-topological solitons
of the Q-ball type, and use the fact that in a first-order cosmological phase
transition, below the critical temperature, there is a value of the soliton
charge above which the soliton becomes unstable and expands, converting space
to the true vacuum, much like a critical bubble in the case of ordinary
tunneling. Using a simple model for the production rate of Q-balls through
charge accretion during a random walk out of equilibrium, I calculate the
probability for the formation of critical charge solitons and estimate the
amount of supercooling needed for the phase transition to be completed.

</DOC>
<DOC>
<DOCNO> 119599 </DOCNO>
Catalog of supersoft X-ray sources


  This catalog comprises an up-to-date (December 1999) list of luminous (>10^36
erg/s), binary supersoft X-ray sources. This electronic version (including the
accompannying Web-pages) supersedes the printed version of Greiner (1996).

</DOC>
<DOC>
<DOCNO> 10842 </DOCNO>
A note on the time evolution of generalized coherent states


  I consider the time evolution of generalized coherent states based on
non-standard fiducial vectors, and show that only for a restricted class of
fiducial vectors does the associated classical motion determine the quantum
evolution of the states. I discuss some consequences of this for path integral
representations.

</DOC>
<DOC>
<DOCNO> 84917 </DOCNO>
On Killing vectors in initial value problems for asymptotically flat


  The existence of symmetries in asymptotically flat space-times are studied
from the point of view of initial value problems. General necessary and
sufficient (implicit) conditions are given for the existence of Killing vector
fields in the asymptotic characteristic and in the hyperboloidal initial value
problem (both of them are formulated on the conformally compactified space-time
manifold).

</DOC>
<DOC>
<DOCNO> 71097 </DOCNO>
Fluctuations of the Metric Tensor and Fermion Propagators


  Conformal fluctuations of the metric tensor at the Planck scale are
considered. They give rise to a lower bound of the proper length. This leads to
finite expressions for quantities related to propagators without the need of
renormalization or regularization. Quantities like the current quark mass or
the effective strong coupling constant have to be reinterpreted.

</DOC>
<DOC>
<DOCNO> 116964 </DOCNO>
JLC Progress


  The JLC is a linear collider project pursued in Japan by researchers centered
around KEK. The R&D status for the JLC project is presented, with emphasis on
recent results from ATF concerning studies of production of ultra-low emittance
beams and from manufacturing research on X-band accelerator structures.

</DOC>
<DOC>
<DOCNO> 72032 </DOCNO>
Neutrino Effects in Nucleosynthesis


  The nucleosynthesis within a Type II supernova occurs in an intense neutrino
flux. I discuss some of the effects associated with neutrino interactions,
including direct synthesis in the neutrino process, the role of neutrinos in
controlling the r-process path and in postprocessing r-process products, and
neutrino oscillation connections.

</DOC>
<DOC>
<DOCNO> 83422 </DOCNO>
Noise-Tolerant Learning, the Parity Problem, and the Statistical Query


  We describe a slightly sub-exponential time algorithm for learning parity
functions in the presence of random classification noise. This results in a
polynomial-time algorithm for the case of parity functions that depend on only
the first O(log n log log n) bits of input. This is the first known instance of
an efficient noise-tolerant algorithm for a concept class that is provably not
learnable in the Statistical Query model of Kearns. Thus, we demonstrate that
the set of problems learnable in the statistical query model is a strict subset
of those problems learnable in the presence of noise in the PAC model.
  In coding-theory terms, what we give is a poly(n)-time algorithm for decoding
linear k by n codes in the presence of random noise for the case of k = c log n
loglog n for some c > 0. (The case of k = O(log n) is trivial since one can
just individually check each of the 2^k possible messages and choose the one
that yields the closest codeword.)
  A natural extension of the statistical query model is to allow queries about
statistical properties that involve t-tuples of examples (as opposed to single
examples). The second result of this paper is to show that any class of
functions learnable (strongly or weakly) with t-wise queries for t = O(log n)
is also weakly learnable with standard unary queries. Hence this natural
extension to the statistical query model does not increase the set of weakly
learnable functions.

</DOC>
<DOC>
<DOCNO> 40074 </DOCNO>
Determination of gamma/Z interference in e+e- annihilation at LEP


  An S-Matrix ansatz is used to determine the mass and width of the Z boson, as
well as the contributions of gamma/Z interference and Z boson exchange to
fermion-pair production. For this purpose we use hadron and lepton-pair
production cross sections and lepton forward-backward asymmetries that have
been measured with the L3 detector at centre-of-mass energies between 87GeV and
189GeV.

</DOC>
<DOC>
<DOCNO> 70275 </DOCNO>
Quantum tunneling in thermal medium


  Time evolution of tunneling phenomena in medium is studied using a standard
model of environment interaction. A semiclassical formula valid at low, but
finite temperatures is derived in the form of integral transform for the
reduced Wigner function, and the tunneling probability in thermal medium is
calculated for a general tunneling potential of one dimensional system. Effect
of dissipation, its time evolution in particular, depends on the behavior of
the potential far beyond the barrier.

</DOC>
<DOC>
<DOCNO> 10381 </DOCNO>
Novel mechanism of photoinduced reversible phase transitions in


  A novel microscopic mechanism of bi-directional structural changes is
proposed for the photo-induced magnetic phase transition in Co-Fe Prussian blue
analogues on the basis of ab initio quantum chemical cluster calculations. It
is shown that the local potential energies of various spin states of Co are
sensitive to the number of nearest neighbor Fe vacancies. As a result, the
forward and backward structural changes are most readily initiated by
excitation of different local regions by different photons. This mechanism
suggests an effective strategy to realize photoinduced reversible phase
transitions in a general system consisting of two local components.

</DOC>
<DOC>
<DOCNO> 8842 </DOCNO>
Front propagation into unstable states: Universal algebraic convergence


  Fronts that start from a local perturbation and propagate into a linearly
unstable state come in two classes: pulled and pushed. ``Pulled'' fronts are
``pulled along'' by the spreading of linear perturbations about the unstable
state, so their asymptotic speed $v^*$ equals the spreading speed of linear
perturbations of the unstable state. The central result of this paper is that
the velocity of pulled fronts converges universally for time $t\to\infty$ like
$v(t)=v^*-3/(2\lambda^*t) + (3\sqrt{\pi}/2)
D\lambda^*/(D{\lambda^*}^2t)^{3/2}+O(1/t^2)$. The parameters $v^*$,
$\lambda^*$, and $D$ are determined through a saddle point analysis from the
equation of motion linearized about the unstable invaded state. The interior of
the front is essentially slaved to the leading edge, and we derive a simple,
explicit and universal expression for its relaxation towards
$\phi(x,t)=\Phi^*(x-v^*t)$. Our result, which can be viewed as a general center
manifold result for pulled front propagation, is derived in detail for the well
known nonlinear F-KPP diffusion equation, and extended to much more general
(sets of) equations (p.d.e.'s, difference equations, integro-differential
equations etc.). Our universal result for pulled fronts thus implies
independence (i) of the level curve which is used to track the front position,
(ii) of the precise nonlinearities, (iii) of the precise form of the linear
operators, and (iv) of the precise initial conditions. Our simulations confirm
all our analytical predictions in every detail. A consequence of the slow
algebraic relaxation is the breakdown of various perturbative schemes due to
the absence of adiabatic decoupling.

</DOC>
<DOC>
<DOCNO> 69174 </DOCNO>
Higher-order QED corrections to single-W production in electron-positron


  Four-fermion processes with a particle lost in the beam pipe are studied at
LEP to perform precision tests of the electroweak theory. Leading higher-order
QED corrections to such processes are analyzed within the framework of the
Structure Functions (SF) approach. The energy scale entering the QED SF is
determined by inspection of the soft and collinear limit of the O(alpha)
radiative corrections to the four-fermion final states, paying particular
attention to the process of single-W production. Numerical predictions are
shown in realistic situations for LEP experiments and compared with existing
results. A Monte Carlo event generator, including exact tree-level matrix
elements, vacuum polarization, higher-order leading QED corrections and
anomalous trilinear gauge couplings, is presented.

</DOC>
<DOC>
<DOCNO> 11441 </DOCNO>
Path-Integral Renormalization Group Method for Numerical Study of


  A numerical algorithm for studying strongly correlated electron systems is
proposed. The groundstate wavefunction is projected out after numerical
renormalization procedure in the path integral formalism. The wavefunction is
expressed from the optimized linear combination of retained states in the
truncated Hilbert space with numerically chosen basis. This algorithm does not
suffer from the negative sign problem and can be applied to any type of
Hamiltonian in any dimension. The efficiency is tested in examples of the
Hubbard model where the basis of Slater determinants is numerically optimized.
We show results on fast convergence and accuracy achieved with small number of
retained states.

</DOC>
<DOC>
<DOCNO> 151200 </DOCNO>
A component of superconnection of 11-dimensional curved superspace at


  We calculate a component of connection superfields and Lorentz superparameter
at second order in anticommuting coordinates in terms of the component fields
of 11-dimensional on-shell supergravity by using `Gauge completion'. This
configuration of superspace holds the $\kappa $-symmetry for supermembrane
Lagrangian and represents 11-dimensional on-shell supergravity.

</DOC>
<DOC>
<DOCNO> 121553 </DOCNO>
On the Gas Surrounding High Redshift Galaxy Clusters


  Francis & Hewett (1993) identified two 10-Mpc scale regions of the high
redshift universe that were seemingly very overdense in neutral hydrogen.
Subsequent observations showed that at least one of these gas-rich regions
enveloped a cluster of galaxies at redshift 2.38. We present improved
observations of the three background QSOs with sightlines passing within a few
Mpc of this cluster of galaxies. All three QSOs show strong neutral hydrogen
absorption at the cluster redshift, suggesting that this cluster (and perhaps
all high redshift clusters) may be surrounded by a ~5 Mpc scale region
containing ~ 10^12 solar masses of neutral gas.
  If most high redshift clusters are surrounded by such regions, we show that
the gas must be in the form of many small (< 1 kpc), dense (> 0.03 cm^-3)
clouds, each of mass < 10^6 solar masses. These clouds are themselves probably
gathered into > 20 kpc sized clumps, which may be galaxy halos or
protogalaxies.
  If this gas exists, it will be partially photoionised by the UV background.
We predict the diffuse Ly-alpha flux from this photoionisation, and place
observational limits on its intensity.

</DOC>
<DOC>
<DOCNO> 69741 </DOCNO>
Left-Right Symmetric Heterotic-String Derived Models


  Recently it was demonstrated that free fermionic heterotic-strings can
produce models with solely the Minimal Supersymmetric Standard Model states in
the low energy spectrum. This unprecedented result provides further strong
evidence for the possibility that the true string vacuum shares some of the
properties of the free fermionic models. Past free fermionic models have
focused on several possible unbroken observable SO(10) subgroups at the string
scale, which include the flipped SU(5) (FSU5), the Pati-Salam (PS) string
models, and the string Standard-like Models (SLM). We extend this study to
include the case in which the SO(10) symmetry is broken to the Left-Right
Symmetric (LRS) gauge group, SO(10) -> SU(3)_C X U(1)_{B-L} X SU(2)_L X
SU(2)_R. We present several models of this type and discuss their
phenomenological features. The most striking new outcome of the LRS string
models, in contrast to the case of the FSU5, the PS, and the SLM string models,
is that they can produce effective field theories that are free of Abelian
anomalies. We discuss the distinction between the two types of free fermionic
models which result in the presence, or absence, of an anomalous U(1). As a
counter example we also present a LRS model that does contain an anomalous
U(1). Additionally, we discuss how in string models the Standard Model spectrum
may arise from the three $\mbf 16$ representations of SO(10), while the
weak-hypercharge does not have the canonical SO(10) embedding.

</DOC>
<DOC>
<DOCNO> 11641 </DOCNO>
First order phase transition with a logarithmic singularity in a model


  Recently, Lipowski [cond-mat/0002378] investigated a stochastic lattice model
which exhibits a discontinuous transition from an active phase into infinitely
many absorbing states. Since the transition is accompanied by an apparent
power-law singularity, it was conjectured that the model may combine features
of first- and second-order phase transitions. In the present work it is shown
that this singularity emerges as an artifact of the definition of the model in
terms of products. Instead of a power law, we find a logarithmic singularity at
the transition. Moreover, we generalize the model in such a way that the
second-order phase transition becomes accessible. As expected, this transition
belongs to the universality class of directed percolation.

</DOC>
<DOC>
<DOCNO> 99333 </DOCNO>
Trace Functionals of the Kontsevich Quantization


  We generalize the notion of trace to the Kontsevich quantization algebra and
show that for all Poisson manifolds representable by quotients of a symplectic
manifold by a Hamiltonian action of a nilpotent Lie group, the trace is given
by integration with respect to a unimodular volume form.

</DOC>
<DOC>
<DOCNO> 169994 </DOCNO>
A New and Radical Kind of Contextuality in the Models of Meyer et al


  It is shown that the models recently proposed by Meyer, Kent and Clifton
(MKC) exhibit a novel kind of contextuality, which we term existential
contextuality. It is a particularly radical kind of contextuality, since it is
not simply the pre-existing value but the actual existence of an observable
which is context-dependent. This result confirms the point made elsewhere, that
the MKC models do not, as the authors claim, ''nullify'' the Kochen-Specker
theorem. It may also be of some independent interest.

</DOC>
<DOC>
<DOCNO> 71935 </DOCNO>
Spin Dependent Fragmentation Functions for Heavy Flavor Baryons and


  Spin dependent fragmentation functions for heavy flavor quarks to fragment
into heavy baryons are calculated in a quark-diquark model. The production of
intermediate spin 1/2 and 3/2 excited states is explicity included. $\Lambda_b$
, $\Lambda_c$ and $\Xi_c$ production rate and polarization at LEP energies are
calculated and, where possible, compared with experiment. A different approach,
also relying on a heavy quark-diquark model, is proposed for the small momentum
transfer inclusive production of polarized heavy flavor hyperons. The predicted
$\Lambda_c$ polarization is roughly in agreement with experiment.

</DOC>
<DOC>
<DOCNO> 10802 </DOCNO>
Statistics of energy levels and zero temperature dynamics for


  We consider the zero-temperature dynamics for the infinite-range, non
translation invariant one-dimensional spin model introduced by Marinari, Parisi
and Ritort to generate glassy behaviour out of a deterministic interaction. It
is shown that there can be a large number of metatastable (i.e., one-flip
stable) states with very small overlap with the ground state but very close in
energy to it, and that their total number increases exponentially with the size
of the system.

</DOC>
<DOC>
<DOCNO> 120629 </DOCNO>
The environments of FRII radio sources


  Using ROSAT observations, we estimate gas pressures in the X-ray-emitting
medium surrounding 63 FRII radio galaxies and quasars. We compare these
pressures with the internal pressures of the radio-emitting plasma estimated by
assuming minimum energy or equipartition. In the majority of cases (including
12/13 sources with modelled, spatially resolved X-ray emission) radio sources
appear to be underpressured with respect to the external medium, suggesting
that simple minimum-energy arguments underestimate the sources' internal energy
density. We discuss possible departures from the minimum energy condition and
the consequences of our result for models of the dynamics of radio galaxies, in
particular self-similar models (Kaiser & Alexander 1997).

</DOC>
<DOC>
<DOCNO> 119781 </DOCNO>
X-Ray and Optical Variability in NGC 4051 and the Nature of Narrow-Line


  We report on the results of a three-year program of coordinated X-ray and
optical monitoring of the narrow-line Seyfert 1 galaxy NGC 4051. The rapid
continuum variations observed in the X-ray spectra are not detected in the
optical, although the time-averaged X-ray and optical continuum fluxes are
well-correlated. Variations in the flux of the broad Hbeta line are found to
lag behind the optical continuum variations by 6 days (with an uncertainty of
2-3 days), and combining this with the line width yields a virial mass estimate
of about 1.1 million solar masses, at the very low end of the distribution of
AGN masses measured by line reverberation. Strong variability of He II 4686 is
also detected, and the response time measured is similar to that of Hbeta, but
with a much larger uncertainty. The He II 4686 line is almost five times
broader than Hbeta, and it is strongly blueward asymmetric, as are the
high-ionization UV lines recorded in archival spectra of NGC 4051. The data are
consistent with the Balmer lines arising in a low to moderate inclination
disk-like configuration, and the high-ionization lines arising in an outflowing
wind, of which we observe preferentially the near side. Previous observations
of the narrow-line region morphology of this source suggest that the system is
inclined by about 50 degrees, and if this is applicable to the broad
Hbeta-emitting region, a central mass of about 1.4 million solar masses can be
inferred. During the third year of monitoring, both the X-ray continuum and the
He II 4686 line went into extremely low states, although the optical continuum
and the Hbeta broad line were both still present and variable. We suggest that
the inner part of the accretion disk may have gone into an advection-dominated
state, yielding little radiation from the hotter inner disk.

</DOC>
<DOC>
<DOCNO> 99637 </DOCNO>
Generalization of the Bloch-Messiah-Zumino theorem


  It is shown how to construct a basis in which two arbitrary complex
antisymmetric matrices C and C' acquire simultaneously canonical forms. The
present construction is not restricted by any conditions on properties of the
C^+C' matrix. Canonical bases pertaining to the generator-coordinate-method
treatment of many-fermion systems are discussed.

</DOC>
<DOC>
<DOCNO> 11784 </DOCNO>
Energy Level Quasi-Crossings: Accidental Degeneracies or Signature of


  In the field of quantum chaos, the study of energy levels plays an important
role. The aim of this review paper is to critically discuss some of the main
contributions regarding the connection between classical dynamics,
semi-classical quantization and spectral statistics of energy levels. In
particular, we analyze in detail degeneracies and quasi-crossings in the
eigenvalues of quantum Hamiltonians which are classically non-integrable.
Summary: 1. Introduction; 2. Quasi-Crossing and Chaos; 3. Molecular
Spectroscopy; 4. Nuclear Models; 4.1 Zirnbauer-Verbaashot-Weidenmuller Model;
4.2 Lipkin-Meshow-Glick Model; 5. Particle Physics and Field Theory; 6.
Conclusions.

</DOC>
<DOC>
<DOCNO> 117407 </DOCNO>
Shell-model calculations of stellar weak interaction rates: II. Weak


  Based on large-scale shell model calculations we have determined the electron
capture, positron capture and beta-decay rates on more than 100 nuclei in the
mass range A=45-65. The rates are given for densities \rho Y_e =10^7-10^{10}
mol/cm^3 and temperatures T=10^9-10^{10} K and hence are relevant for both
types of supernovae (Type Ia and Type II). The shell model electron capture
rates are significantly smaller than currently assumed. For proton-to-baryon
ratios Y_e=0.42-0.46 mol/g, the beta-decay rates are faster than the electron
capture rates during the core collapse of a massive star.

</DOC>
<DOC>
<DOCNO> 72289 </DOCNO>
MNS Parameters from Neutrino Oscillations, Single Beta Decay and Double


  We examine the constraints on the MNS lepton mixing matrix =66rom the present
and future experimental data of the neutrino oscillation, tritium beta decay,
and neutrinoless double beta decay for Majorana neutrinos. We show that the
small mixing angle solutions for solar neutrino problem are disfavored for
small averaged mass ($<m_\nu>$) of neutrinoless double beta decay ($\leq 0.01$
eV) in the inverse neutrino mass hierarchy scenario. This is the case even in
the normal mass hierarchy scenario except for very restrictive value of the
averaged neutrino mass ($\bar{m_\nu}$) of single beta decay. The lower mass
bound for $\bar{m_\nu}$ is given from the present neutrino oscillation data. We
obtain some relations between $<m_\nu>$ and $\bar{m_\nu}$. The constraints on
the Majorana CP violating phases are also given.

</DOC>
<DOC>
<DOCNO> 8775 </DOCNO>
Quantum Hall effect at weak magnetic field: New float-up picture


  The fate of integer quantum Hall effect (IQHE) at weak magnetic field is
studied numerically in the presence of {\it correlated} disorders. We find a
systematic {\it float-up} and {\it merging} picture for extended levels on the
low-energy side which results in direct transitions from higher-plateau IQHE
states to the insulator. Such direct transitions are controlled by a quantum
critical point with a {\it universal} scaling form of conductance. The phase
diagram is in good agreement with recent experiments. The issue of continuum
vs. lattice model is also discussed.

</DOC>
<DOC>
<DOCNO> 174533 </DOCNO>
Threshold Reaction Rates Inside and on the Surface of Thick W-Na Target


  The preliminary results are presented of the experimental determination of
threshold reaction rates in experimental samples made of Al, Co, Bi, In, Au, to
name but a few, placed both inside and on the surface of extended thick W-Na
target irradiated with 0.8 GeV protons. The target consists of 26 alternating
discs each 150 mm in diameter: 6 tungsten discs are 20 mm thick, 7 tungsten
discs are 40 mm thick, and 13 sodium discs are 40 mm thick. The relative
position of discs is matched with the aim of flattening the neutron field along
the target surface. The comparison is made of the measured rates with results
of their simulation using the LAHET and KASKAD-S codes, and the ENDF/B6,
MENDL2, MENDL2P, SADKO-2, and ABBN-93 databases. The results are of interest
both in terms of integral data collection and to test the up-to-the-date
predictive power of the codes applied in designing of hybrid Accelerator Driven
System (ADS) systems that use tungsten targets cooled with sodium.

</DOC>
<DOC>
<DOCNO> 117272 </DOCNO>
Consistent Equation of Classical Gravitation to Quantum Limit and Beyond


  General Relativity makes a distinction between mass and space. Mass tells
space how to curve and space tells mass how to move. Newtonian gravity equation
makes a distinction between them by having its numerator as mass effect and its
denominator as inverse square law space effect at macroscopic approximation. At
microscopic distances it makes sense to substitute surface-to-surface distance
between two nucleons for center-to-center distance between them to account for
the mass space distinction, keeping in mind the smallest distance between
coupled nucleons is Planck length. Any distance less than Planck makes no sense
in the classical world. When we calculate the force between two nucleons of one
femtometer diameter each, separated by a surface-to-surface distance of Planck
length, we get the force that matches well known nuclear force i.e. 10E40 times
the value of the force of gravitation ``g'' calculated by assuming the
Newtonian center-to-center distance of 1 femtometer. What we get is what is
described as the nuclear force in scientific literature. This leads to the
question: Is the nuclear force (well recognized secondary effect of color
force) high intensity gravitation?

</DOC>
<DOC>
<DOCNO> 151256 </DOCNO>
On Chiral Symmetry Breaking in a Constant Magnetic Field in Higher


  Chiral symmetry breaking in the Nambu-Jona-Lasinio model in a constant
magnetic field is studied in spacetimes of dimension D > 4. It is shown that a
constant magnetic field can be characterized by [(D-1)/2] parameters. For the
maximal number of nonzero field parameters, we show that there is an effective
reduction of the spacetime dimension for fermions in the infrared region D
$\to$ 1 + 1 for even-dimensional spacetimes and D $\to$ 0 + 1 for
odd-dimensional spacetimes. Explicit solutions of the gap equation confirm our
conclusions.

</DOC>
<DOC>
<DOCNO> 10146 </DOCNO>
Slave-boson mean-field theory of spin- and orbital-ordered states in the


  The mean-field theory with the use of the slave-boson functional method is
generalized to take account of the spin- and orbital-ordered state in the
doubly degenerate Hubbard model. Some numerical calculations are presented of
the antiferromagnetic orbital-ordered state in the half-filled simple-cubic
model. The orbital order in the present theory is much reduced compared with
that in the Hartree-Fock approximation because of the large orbital
fluctuations. From a comparison of the ground-state energy, the
antiferromagnetic orbital state is shown to be unstable against the
antiferromagnetic spin state, although the situation becomes reversed when the
exchange interaction is {\it negative}.

</DOC>
<DOC>
<DOCNO> 150348 </DOCNO>
The basic principles of geometrization of the quantum mechanics


  The basic principles of the quantum mechanics in the K-field formalism (see
author's papers) are stated in the paper. K-field formalism arises from
geometric generalization of de Broglie postulate. So, the quantum theory
equations (including well-known Schrodinger, Klein-Gordon and quadratic Dirac
equations) are obtained as the free wave equations on a manifold metrizing
force interactions of particles. In this paper, describing wave properties of
particles we will restricted ourself with construction special geometric
formulation of force interactions.

</DOC>
<DOC>
<DOCNO> 12879 </DOCNO>
Steady State Thermodynamics of Langevin Systems


  We study Langevin dynamics describing nonequilibirum steady states. Employing
the phenomenological framework of steady state thermodynamics constructed by
Oono and Paniconi [Prog. Theor. Phys. Suppl. {\bf130}, 29 (1998)], we find that
the extended form of the second law which they proposed holds for transitions
between steady states and that the Shannon entropy difference is related to the
excess heat produced in an infinitely slow operation. A generalized version of
the Jarzynski work relation plays an important role in our theory.

</DOC>
<DOC>
<DOCNO> 10792 </DOCNO>
Liquid-Solid Phase Transition of the System with Two particles in a


  We study the statistical properties of two hard spheres in a two dimensional
rectangular box. In this system, the relation like Van der Waals equation loop
is obtained between the width of the box and the pressure working on side
walls. The auto-correlation function of each particle's position is calculated
numerically. By this calculation near the critical width, the time at which the
correlation become zero gets longer according to the increase of the height of
the box. Moreover, fast and slow relaxation processes like $\alpha$ and $\beta$
relaxations observed in supper cooled liquid are observed when the height of
the box is sufficiently large. These relaxation processes are discussed with
the probability distribution of relative position of two particles.

</DOC>
<DOC>
<DOCNO> 84660 </DOCNO>
Removal of interference from external coherent signals


  We present a technique that we call coherent line removal, for removing
external coherent interference from gravitational wave interferometer data. We
illustrate the usefulness of this technique applying it to the the data
produced by the Glasgow laser interferometer in 1996 and removing all those
lines corresponding to the electricity supply frequency and its harmonics. We
also find that this method seems to reduce the level of non-Gaussian noise
present in the interferometer and therefore, it can raise the sensitivity and
duty cycle of the detectors.

</DOC>
<DOC>
<DOCNO> 70868 </DOCNO>
Isospin symmetry breaking and direct CP violation in B -> \rho \gamma


  We discuss the isospin symmetry breaking quantity \Delta^{\pm 0} =
\Gamma(B^\pm -> \rho^\pm \gamma)/[2 \Gamma(B^0 -> \rho^0 \gamma)] - 1, and the
direct CP violation in B^\pm -> \rho^\pm \gamma within and beyond the standard
model. After showing that the leading-order calculation would be a good
approximation in such models, we argue that measurements of these quantities
would be able to disentagle physics beyond the standard model.

</DOC>
<DOC>
<DOCNO> 117004 </DOCNO>
Design of 11.8 MHZ Buncher for Isac at Triumf


  The high energy beam transport (HEBT) line for the ISAC radioactive beam
facility at TRIUMF requires an 11.8 MHz buncher. The main requirements of the
buncher are to operate in cw mode with a velocity acceptance of 2.2% and an
effective voltage of 100 kV, which for a three gap buncher gives a drift tube
voltage of 30 kV. A lumped element circuit is more suitable than a distributed
rf structure for this low frequency of operation. The resonant frequency of
11.8 MHz is obtained by an inductive coil in parallel with the capacitance of
the drift tube. The coil is housed in a dust free box at atmospheric pressure
whereas the drift tube is placed in a vacuum chamber and an rf feedthrough
connects them. Two design of this feedthrough, one using disk and one using
tubular ceramics, operating at 30 kV rf, are described in this paper. MAFIA and
SUPERFISH codes are used to simulate the fields in the feedthroughs,
particularly around the ceramic metal interfaces. Test results of the prototype
feedthroughs are presented and the choice of the proposed final solution is
outlined.

</DOC>
<DOC>
<DOCNO> 68123 </DOCNO>
Complete one-loop analysis of the nucleon's spin polarizabilities


  We present a complete one-loop analysis of the four nucleon spin
polarizabilities in the framework of heavy baryon chiral perturbation theory.
The first non-vanishing contributions to the isovector and first corrections to
the isoscalar spin polarizabilities are calculated. No unknown parameters enter
these predictions. We compare our results to various dispersive analyses. We
also discuss the convergence of the chiral expansion and the role of the delta
isobar.

</DOC>
<DOC>
<DOCNO> 84533 </DOCNO>
Brane versus shell cosmologies in Einstein and Einstein-Gauss-Bonnet


  We first illustrate on a simple example how, in existing brane cosmological
models, the connection of a 'bulk' region to its mirror image creates matter on
the 'brane'. Next, we present a cosmological model with no $Z_2$ symmetry which
is a spherical symmetric 'shell' separating two metrically different
5-dimensional anti-de Sitter regions. We find that our model becomes
Friedmannian at late times, like present brane models, but that its early time
behaviour is very different: the scale factor grows from a non-zero value at
the big bang singularity. We then show how the Israel matching conditions
across the membrane (that is either a brane or a shell) have to be modified if
more general equations than Einstein's, including a Gauss-Bonnet correction,
hold in the bulk, as is likely to be the case in a low energy limit of string
theory. We find that the membrane can then no longer be treated in the thin
wall approximation. However its microphysics may, in some instances, be simply
hidden in a renormalization of Einstein's constant, in which cases Einstein and
Gauss-Bonnet membranes are identical.

</DOC>
<DOC>
<DOCNO> 80909 </DOCNO>
A smoother approach to scaling by suppressing monopoles and vortices


  Suppressing monopoles and vortices by introducing large chemical potentials
for them in the Wilson action for the SU(2) lattice gauge theory, we study the
nature of the deconfinement phase transition on N_sigma^3 X N_tau lattices for
N_tau =4, 5, 6 and 8 and N_sigma = 8-16. Using finite size scaling theory, we
obtain \omega = 1.93 +/- 0.03 for N_tau = 4, in excellent agreement with
universality. The critical couplings for N_tau= 4, 5, 6 and 8 lattices exhibit
large shifts towards the strong coupling region when compared with the usual
Wilson action, and suggest a lot smoother approach to scaling.

</DOC>
<DOC>
<DOCNO> 151898 </DOCNO>
Vibration modes of giant gravitons


  We examine the spectrum of small vibrations of giant gravitons, when the
gravitons expand in the anti-de-Sitter space and when they expand on the
sphere. For any given angular harmonic, the modes are found to have frequencies
related to the curvature length scale of the background; these frequencies are
independent of radius (and hence angular momentum) of the brane itself. This
implies that the holographic dual theory must have, in a given R charge sector,
low-lying non-BPS excitations with level spacings independent of the R charge.

</DOC>
<DOC>
<DOCNO> 101921 </DOCNO>
Periodic Complexes and Group Actions


  In this paper we show that the cohomology of a connected CW complex is
periodic if and only if it is the base space of an orientable spherical
fibration with total space that is homotopically finite dimensional. As
applications we characterize those discrete groups that act freely and properly
on a cartesian product of euclidean space and a sphere; we construct
non-standard free actions of rank two simple groups on finite complexes Y
homotopy equivalent to a product of two spheres and we prove that a finite
p-group P acts freely on such a complex if and only if it does not contain a
subgroup isomorphic to Z/p X Z/p X Z/p.

</DOC>
<DOC>
<DOCNO> 12949 </DOCNO>
Anisotropic charge transfer mechanism in La$_{2-x}$Sr$_x$CuO$_4$ and


  Raman spectra of La$_{2-x}$Sr$_x$CuO$_4$ are similar to those of
Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ except for the split two-magnon peaks at the
stripe phase and the stronger step-like decrease in the low energy $B_{\rm 2g}$
spectra. The suppressed $B_{\rm 1g}$ spectral region below the two-magnon peak
decreases as the carrier density increases, whereas the energy of the step-like
suppression is little dependent on the carrier density. It suggests the
anisotropic charge transfer mechanism coupled with magnetic excitations along
the nearest neighbor Cu sites and the phononic excitations along the diagonal
direction.

</DOC>
<DOC>
<DOCNO> 40192 </DOCNO>
Future Reactor Neutrino Oscillation Experiments at Krasnoyarsk


  Recent studies of atmospheric neutrinos and the results from CHOOZ and
Palo-Verde experiment call for new and more sensitive searches for neutrino
oscillations at reactors. The main goal of the project considered here is to
look for very small mixing angle oscillations of electron neutrinos in the
atmospheric neutrino mass parameter region around \Delta m^2 ~3 10^-3 eV^2 and
to define the element U_{e3} of the neutrino mixing matrix (U_{e3}is the
contribution of the mass-3 state to the electron neutrino flavor state). The
practical goal of the project is to decrease, relative to the CHOOZ, the
statistic and systematic errors as much as possible. To achieve this we plan to
use two identical antineutrino detectors each with a ~50-ton liquid
scintillator target located at ~1100 m and ~250 m from the underground reactor
(~600 mwe). Much attention is given to the detector calibration and monitoring
procedures. As a first step we consider two much smaller pilot detectors each
of ~ a 3 ton target mass stationed at ~20 m and 35-60 m from the reactor. The
goals of this first stage are: (i) to accumulate necessary experience and (ii)
to investigate with electron neutrinos the LSND mass parameter region.

</DOC>
<DOC>
<DOCNO> 70875 </DOCNO>
Light Scalars in Cosmology


  I discuss here some of the constraints imposed by quantum and gravitational
corrections on two hypothetical excitations, axions and quintessence, which
have important cosmological implications. Although these corrections can be
kept under control, the resulting constraints are not too natural. In
particular, to keep the quintessence field light one must essentially decouple
it from ordinary matter. Some possible suggestions of how to avoid these
troubles are briefly touched upon.

</DOC>
<DOC>
<DOCNO> 10583 </DOCNO>
New algorithm and results for the three-dimensional random field Ising


  The random field Ising model with Gaussian disorder is studied using a new
Monte Carlo algorithm. The algorithm combines the advantanges of the replica
exchange method and the two-replica cluster method and is much more efficient
than the Metropolis algorithm for some disorder realizations. Three-dimensional
sytems of size $24^3$ are studied. Each realization of disorder is simulated at
a value of temperature and uniform field that is adjusted to the phase
transition region for that disorder realization. Energy and magnetization
distributions show large variations from one realization of disorder to
another. For some realizations of disorder there are three well separated peaks
in the magnetization distribution and two well separated peaks in the energy
distribution suggesting a first-order transition.

</DOC>
<DOC>
<DOCNO> 69638 </DOCNO>
Supergravity Tensor Calculus in 5D from 6D


  Supergravity tensor calculus in five spacetime dimensions is derived by
dimensional reduction from the d=6 superconformal tensor calculus. In
particular, we obtain an off-shell hypermultiplet in 5D from the on-shell
hypermultiplet in 6D. Our tensor calculus still retains the dilatation gauge
symmetry so that it becomes a trivial gauge fixing to make the Einstein term
canonical in a general matter-Yang-Mills-supergravity coupled system.

</DOC>
<DOC>
<DOCNO> 102880 </DOCNO>
The simplest examples where the simplex method cycles and conditions


  This paper introduces a class of linear programming examples which cause the
simplex method to cycle indefinitely and which are the simplest possible
examples showing this behaviour. The structure of examples from this class
repeats after two iterations. Cycling is shown to occur for both the most
negative reduced cost and steepest edge column selection criteria. In addition
it is shown that the EXPAND anti-cycling procedure of Gill et al.is not
guaranteed to prevent cycling.

</DOC>
<DOC>
<DOCNO> 152501 </DOCNO>
BPS Bound States Of D0-D6 And D0-D8 Systems In A B-Field


  The D0-D6 system, which is not supersymmetric in the absence of a
Neveu-Schwarz B-field, becomes supersymmetric if a suitable constant B-field is
turned on. On one side of the supersymmetric locus, this system has a BPS bound
state, and on the other side it does not. After compactification on T^6, this
gives a simple example in which the number of 1/8 BPS states jumps as the
moduli of the compactification are changed. The D0-D8 system in a B-field has
two different supersymmetric loci, only one of which is continuously connected
to the familiar supersymmetric D0-D8 system without a B-field. In a certain
range, the D0-D8 system also has a BPS bound state. In the limit in which the
B-field goes to infinity, supersymmetric D0-D6 and D0-D8 systems and their
bound states can be studied using noncommutative Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 118310 </DOCNO>
The Schweizer-Middleditch star revisited


  We have re-observed and re-analysed the optical spectrum of the
Schweizer-Middleditch star, a hot subdwarf which lies along almost the same
line-of-sight as the centre of the historic SN1006 supernova remnant (SNR).
Although this object is itself unlikely to be the remnant of the star which
exploded in 1006AD, Wellstein et al. (1999) have demonstrated that it could be
the remnant of the donor star in a pre-supernova Type Ia interacting binary, if
it possesses an unusually low mass. We show that, if it had a mass of 0.1-0.2
Msun, the SM star would lie at the same distance (~800pc) as the SNR as
estimated by Willingale et al. (1995). However, most distance estimates to
SN1006 are much larger than this, and there are other convincing arguments to
suggest that the SM star lies behind this SNR. Assuming the canonical subdwarf
mass of 0.5 Msun, we constrain the distance of the SM star as 1050 pc<d<2100
pc. This places the upper limit on the distance of SN1006 at 2.1 kpc.

</DOC>
<DOC>
<DOCNO> 100335 </DOCNO>
On the relation between the A-polynomial and the Jones polynomial


  In previous joint work with Frohman and Lofaro a noncommutative
generalization of the A-polynomial of a knot was introduced, consisting of a
finitely generated ideal of polynomials (the noncommutative A-ideal) in the
quantum plane. The present paper shows that the noncommutative A-ideal of a
knot, together with finitely many of its colored Jones polynomials determines
all other colored Jones polynomials. Also, for particular knots, such as the
unknot and the trefoil, the noncommutative A-ideal completely determines all
colored Jones polynomials.

</DOC>
<DOC>
<DOCNO> 118035 </DOCNO>
Prospects of Variable Star Research by Future Space Missions


  ESA and NASA are studying projects having a tremendous return on variable
star research. Other national space agencies are also studying or developing
projects of smaller costs but with impressive returns. The projects range from
global Galactic surveys like the ESA mission GAIA which will give photometric
time series for about 1 billion stars, to detailed pulsation modes studies like
the CNES mission COROT which could reach a photometric precision lower than 1
ppm. The presentation will emphasize the future astrometric, asteroseismologic
and planet detection missions.

</DOC>
<DOC>
<DOCNO> 102612 </DOCNO>
Semi-infinite A-variations of Hodge structure over extended Kahler cone


  This is an expanded comment on Barannikov's paper math.AG/0006193. A
symplectic version of his construction is discussed. It is shown that the
duality transformation for mirror torus fibrations over the same Monge-Ampere
manifold exchanges semi-infinite A-variations of Hodge structure introduced in
this paper with Barannikov's semi-infinite B-variations of Hodge structure.

</DOC>
<DOC>
<DOCNO> 120362 </DOCNO>
The Young Starburst Nucleus of the Wolf-Rayet LINER Galaxy NGC 6764


  NIR K band imaging spectroscopy of the central 8'' (1.3 kpc) in the
Wolf-Rayet LINER galaxy NGC6764 shows that the most recent star formation is
most likely still unresolved at sub-arcsecond resolution (< 100pc). The
continuum source has a size of about 1.5''. The H_2 emission is resolved
showing a rotating ring/disk of ~1.2'' diameter. An analysis of the nuclear
stellar light using population synthesis models in conjunction with NIR
spectral synthesis models suggests following star formation history: Two
starbursts with decay times of 3 Myr occurred 3 - 5 Myr and 15 - ~50 Myr ago.
Continuous star formation over at least 1Gyr can also explain the observed
parameter. However, the mass relocation and consumption involved as well as the
different spatial distribution of the lines associated with the star formation
strongly favor the 'two starburst' scenario. In that scenario, up to 35% of the
total observed Br_gamma flux could still be due to the AGN. In contrast to
other starburst galaxies (e.g. M82, NGC 7552), the younger starburst in NGC6764
is very likely located closer to the nucleus and surrounded by the older
starburst. One possible explanation can be that the stellar bar still
transports gas down to radii close to the nucleus. This suggests that the
massive star formation activity is directly competing with the AGN for the
fuel. The 44 ksec. HRI ROSAT data show the presence of a X-ray source (probably
an AGN) which varies by more than a factor of 2 over a time scale of 7 days.
This implies the presence of a compact source with a discrete or at most 1000
AU source size. In addition, we find an extended X-ray component which looks
similar to published VLA radio continuum maps.

</DOC>
<DOC>
<DOCNO> 9497 </DOCNO>
Dark soliton states of Bose-Einstein condensates in anisotropic traps


  Dark soliton states of Bose-Einstein condensates in harmonic traps are
studied both analytically and computationally by the direct solution of the
Gross-Pitaevskii equation in three dimensions. The ground and self-consistent
excited states are found numerically by relaxation in imaginary time. The
energy of a stationary soliton in a harmonic trap is shown to be independent of
density and geometry for large numbers of atoms. Large amplitude field
modulation at a frequency resonant with the energy of a dark soliton is found
to give rise to a state with multiple vortices. The Bogoliubov excitation
spectrum of the soliton state contains complex frequencies, which disappear for
sufficiently small numbers of atoms or large transverse confinement. The
relationship between these complex modes and the snake instability is
investigated numerically by propagation in real time.

</DOC>
<DOC>
<DOCNO> 12316 </DOCNO>
Localization-induced coherent backscattering effect in wave dynamics


  We investigate the statistics of single-mode delay times of waves reflected
from a disordered waveguide in the presence of wave localization. The
distribution of delay times is qualitatively different from the distribution in
the diffusive regime, and sensitive to coherent backscattering: The probability
to find small delay times is enhanced by a factor close to sqrt(2) for
reflection angles near the angle of incidence. This dynamic effect of coherent
backscattering disappears in the diffusive regime.

</DOC>
<DOC>
<DOCNO> 39623 </DOCNO>
Limit on a horizontal emittance in high energy muon colliders due to


  It is shown that at a 100 TeV muon collider the synchrotron radiation in the
ring will determine the minimum horizontal emittance.

</DOC>
<DOC>
<DOCNO> 120020 </DOCNO>
Curvature Dependence of Peaks in the Cosmic Microwave Background


  The widely cited formula $\ell_1\simeq 200 \Omega_0^{-1/2}$ for the multipole
number of the first Doppler peak is not even a crude approximation in the case
of greatest current interest, in which the cosmic mass density is less than the
vacuum energy density. For instance, with $\Omega_M$ fixed at 0.3, the position
of any Doppler peak varies as $\Omega_0^{-1.58}$ near $\Omega_0=1$.

</DOC>
<DOC>
<DOCNO> 122894 </DOCNO>
Nonthermal Emission in Radio Galaxies from Simulated Relativistic


  We perform a series of so-called ``synthetic observations'' on a set of 3D
MHD jet simulations which explicitly include energy-dependent transport of
relativistic electrons, as described in the companion paper by Jones,
Tregillis, & Ryu. Analyzing them in light of the complex source dynamics and
energetic particle distributions described in that paper, we find that the
standard model for radiative aging in radio galaxies does not always adequately
reflect the detailed source structure.

</DOC>
<DOC>
<DOCNO> 151620 </DOCNO>
Double-Scaling Limit of a Broken Symmetry Quantum Field Theory


  The Ising limit of a conventional Hermitian parity-symmetric scalar quantum
field theory is a correlated limit in which two bare Lagrangian parameters, the
coupling constant $g$ and the {\it negative} mass squared $-m^2$, both approach
infinity with the ratio $-m^2/g=\alpha>0$ held fixed. In this limit the
renormalized mass of the asymptotic theory is finite. Moreover, the limiting
theory exhibits universal properties. For a non-Hermitian $\cal PT$-symmetric
Lagrangian lacking parity symmetry, whose interaction term has the form
$-g(i\phi)^N/N$, the renormalized mass diverges in this correlated limit.
Nevertheless, the asymptotic theory still has interesting properties. For
example, the one-point Green's function approaches the value
$-i\alpha^{1/(N-2)}$ independently of the space-time dimension $D$ for $D<2$.
Moreover, while the Ising limit of a parity-symmetric quantum field theory is
dominated by a dilute instanton gas, the corresponding correlated limit of a
$\cal PT$-symmetric quantum field theory without parity symmetry is dominated
by a constant-field configuration with corrections determined by a
weak-coupling expansion in which the expansion parameter (the amplitude of the
vertices of the graphs in this expansion) is proportional to an inverse power
of $g$. We thus observe a weak-coupling/strong-coupling duality in that while
the Ising limit is a strong-coupling limit of the quantum field theory, the
expansion about this limit takes the form of a conventional weak-coupling
expansion. A possible generalization of the Ising limit to dimensions $D<4$ is
briefly discussed.

</DOC>
<DOC>
<DOCNO> 68445 </DOCNO>
The Use of Nuclear Beta-decay as a Test of Bulk Neutrinos in Extra


  Theories which include neutrinos in large extra dimensions can be constrained
by nuclear beta decay experiments. We examine universality of beta decay
strengths of Fermi transitions. From this we find that the extra dimensional
Yukawa coupling for a higher dimensional scale of 10 TeV, and two extra
dimensions can be constrained to y < 1. Kinematic implications are also
discussed. In particular, an extra dimensional scenario will produce a tritium
decay endpoint spectrum with a different shape than that for just one massive
state.

</DOC>
<DOC>
<DOCNO> 69233 </DOCNO>
Relativistic Coulomb Resummation in QCD


  A relativistic Coulomb-like resummation factor in QCD is suggested, based on
the solution of the quasipotential equation.

</DOC>
<DOC>
<DOCNO> 68233 </DOCNO>
Neutrino oscillations and large extra dimensions


  Assuming that right-handed neutrinos exist and propagate in some large extra
dimensions, we attempt to give a comprehensive description of the phenomenology
of neutrino oscillations. A few alternative explanations of the atmospheric
neutrino anomaly emerge, different from the standard nuMu --> nuTau or nuMu -->
nuSterile interpretations. Constraints from nucleosynthesis and supernova 1987a
are discussed. The constraints from SN1987a indicates a maximum radius of any
extra dimension of about 1 Angstrom.

</DOC>
<DOC>
<DOCNO> 80765 </DOCNO>
Green's Function Monte Carlo approach to SU(3) Yang-Mills theory in


  A 'forward walking' Green's Function Monte Carlo algorithm is used to obtain
expectation values for SU(3) lattice Yang-Mills theory in (3+1) dimensions. The
ground state energy and Wilson loops are calculated, and the finite-size
scaling behaviour is explored. Crude estimates of the string tension are
derived, which agree with previous results at intermediate couplings; but more
accurate results for larger loops will be required to establish scaling
behaviour at weak coupling.

</DOC>
<DOC>
<DOCNO> 70079 </DOCNO>
Compton-like interaction of massive neutrinos with virtual photons


  The amplitude of a Compton-like process nu_i gamma^* -> nu_j gamma^* with
virtual photons is calculated in the standard GWS theory with lepton mixing.
The contribution of this process to the high energy neutrino scattering on the
nucleus with single photon radiation nu N -> nu N gamma is discussed. The
bremsspectrum and the total cross-section are estimated in the leading log
approximation.

</DOC>
<DOC>
<DOCNO> 152338 </DOCNO>
Tachyon condensation in cubic superstring field theory


  It has been conjectured that at the stationary point of the tachyon potential
for the non-BPS D-brane or brane-anti-D-brane pair, the negative energy density
cancels the brane tension. We study this conjecture using a cubic superstring
field theory with insertion of a double-step inverse picture changing operator.
We compute the tachyon potential at levels (1/2,1) and (2,6). In the first case
we obtain that the value of the potential at the minimum is 97.5% of the non
BPS D-brane tension. Using a special gauge in the second case we get 105.8% of
the tension.

</DOC>
<DOC>
<DOCNO> 118830 </DOCNO>
The Age of the Solar Neighbourhood


  High-quality Hipparcos data for a complete sample of nearly 12000
main-sequence and subgiant stars, together with Padua isochrones, are used to
constrain the star-formation history of the solar neigbourhood and the
processes that stochastically accelerate disk stars. The velocity dispersion of
a coeval group of stars is found to increase with time from ~8 kms at birth as
t^{0.33}. In the fits, the slope of the IMF near 1 Msun proves to be degenerate
with the rate at which the star-formation rate declines. If the slope of the
IMF is to lie near Salpeter's value, -2.35, the star-formation rate has to be
very nearly constant. The age of the solar neighbourhood is found to be
11.2+/-0.75 Gyr with remarkably little sensitivity to variations in the assumed
metallicity distribution of old disk stars. This age is only a Gyr younger than
the age of the oldest globular clusters when the same isochrones and distance
scale are employed. It is compatible with current indications of the redshift
of luminous galaxy formation only if there is a large cosmological constant. A
younger age is formally excluded because it provides a poor fit to the number
density of red stars. Since this density is subject to a significantly
uncertain selection function, ages as low as 9 Gyr are plausible even though
they lie outside our formal error bars.

</DOC>
<DOC>
<DOCNO> 119188 </DOCNO>
Resonant Scattering of Emission Lines in Coronal Loops: Effects on Image


  We have investigated the effects of resonant scattering of emission lines on
the image morphology and intensity from coronal loop structures. It has
previously been shown that line of sight effects in optically thin line
emission can yield loop images that appear uniformly bright at one viewing
angle, but show ``looptop sources'' at other viewing angles. For optically
thick loops where multiple resonant scattering is important, we use a 3D Monte
Carlo radiation transfer code. Our simulations show that the intensity
variation across the image is more uniform than the optically thin simulation
and, depending on viewing angle, the intensity may be lower or higher than that
predicted from optically thin simulations due to scattering out of or into the
line of sight.

</DOC>
<DOC>
<DOCNO> 72030 </DOCNO>
The Extended Chiral Quark Model in a Tamm-Dancoff Inspired Approximation


  A procedure inspired by the Tamm-Dancoff method is applied to the chiral
quark model which has been extended to include additional degrees of freedom: a
pseudoscalar isoscalar field as well as a triplet of scalar isovector fields.
The simpler, generic $\sigma$ -- model has been used before as a test for the
Tamm-Dancoff inspired approximation (TDIA). The extended chirial quark model is
employed here to investigate possible novel effects of the additional degrees
of freedom as well as to point out the necessesity to introduce a SU(3)
flavour. Model predictions for the axial-vector coupling constant and for the
nucleon magnetic moment obtained in TDIA are compared with experimental values.

</DOC>
<DOC>
<DOCNO> 85338 </DOCNO>
Measuring multipole moments of Weyl metrics by means of gyroscopes


  Using the technique of Rindler and Perlick we calculate the total precession
per revolution of a gyroscope circumventing the source of Weyl metrics. We
establish thereby a link between the multipole moments of the source and an
``observable'' quantity. Special attention deserves the case of the
gamma-metric. As an extension of this result we also present the corresponding
expressions for some stationary space-times.

</DOC>
<DOC>
<DOCNO> 40526 </DOCNO>
Observation of an Excess in the Search for the Standard Model Higgs


  A search has been performed for the Standard Model Higgs boson in the data
sample collected with the ALEPH detector at LEP, at centre-of-mass energies up
to 209GeV. An excess of 3sigma beyond the background expectation is found,
consistent with the production of the Higgs boson with a mass near 114GeV/c2.
Much of this excess is seen in the four-jet analyses, where three high purity
events are selected.

</DOC>
<DOC>
<DOCNO> 122701 </DOCNO>
XMM - Newton observations of Markarian 421


  The BL Lac object Mrk 421 was observed on May 25, 2000 during the XMM -
Newton CAL/PV phase. The high throughput of the X-ray telescopes and the
spectral capabilities of the instruments allow an uninterrupted temporal and
spectral study of the source with unprecedented time resolution. Mrk 421 was
found at a relatively high state with a 2-6 keV flux of (1.3 - 1.9)E-10 erg
cm**-2 s **-1. The observed intensity variations by more than a factor of three
at highest X-ray energies are accompanied by complex spectral variations with
only a small time lag (tau = 265 {+116} {-102} seconds) between the hard and
soft photons. The (0.2-10) keV spectrum can be well fitted by a broken power
law and no absorption structures are found in the source spectrum at the high
spectral resolution of the transmission gratings.

</DOC>
<DOC>
<DOCNO> 119814 </DOCNO>
An $\dot{f}(f)$-frequency dynamics algorithm for gravitational waves


  Coalescence of low mass compact binaries of neutron stars and black holes are
primary burst sources for LIGO and VIRGO.Of importance in the early stages of
observations will be the classification of candidate detections by source-type.
The diversity in source parameters and serendipity in any new window of
observations suggest to consider model-independent detection algorithms. Here a
frequency dynamics algorithm is described which extracts a trajectory in the
$\dot{f}(f)$-plane from the noisy signal. The algorithm is studied in simulated
binary coalescence. Robust results are obtained with experimental noise data.
Experiments show the method to be superior to matched filtering in the presence
of model imperfections.

</DOC>
<DOC>
<DOCNO> 121473 </DOCNO>
Abundance Patterns in the Draco, Sextans and Ursa Minor Dwarf Spheroidal


  The Keck I telescope has been used to obtain HIRES spectra for red giants
belonging to the Draco, Sextans and Ursa Minor dwarf spheroidal (dSph)
galaxies. An analysis of these spectra is presented, along with abundance
ratios for more than 20 elements. The resulting database of element abundances
for 17 stars is the most extensive yet assembled for stars in dSph
environments. Our main findings are summarized as follows: (1) There is
unambiguous evidence for a large internal spread in metallicity in all three
galaxies: our program stars span a range of [Fe/H] = 1.53, 1.40 and 0.73 dex in
Draco, Sextans and Ursa Minor, respectively. (2) The abundance patterns among
the dSph stars are remarkably uniform, suggesting that all three galaxies have
similar nucleosynthetic histories. (3) A comparison of the measured abundance
ratios for our sample of dSph stars with published values for Galactic halo and
disk field stars suggests that the dSph galaxies have 0.02 < [alpha/Fe] < 0.13
dex, whereas the halo field star sample has [alpha/Fe] ~ 0.28 dex over the same
range in metallicity. (4) The most metal-rich dSph stars in our sample have
[Y/Fe] abundances which are significantly lower than those measured for halo
field stars of similar metallicity, while the measured [Ba/Eu] ratios for the
dSph stars suggest that the early chemical evolution of these galaxies was
dominated by the r-process. Taken together, these results suggest that the
Galactic halo is unlikely to have assembled, in its entirety, through the
disruption of dwarf galaxies similar to the low-luminosity dSphs studied here.
(ABRIDGED).

</DOC>
<DOC>
<DOCNO> 152009 </DOCNO>
Abelian Decomposition of Sp(2N) Yang-Mills Theory


  In the previous paper, we generalized the method of Abelian decomposition to
the case of SO(N) Yang-Mills theory. This method that was proposed by Faddeev
and Niemi introduces a set of variables for describing the infrared limit of a
Yang-Mills theory. Here, we extend the decomposition method further to the
general case of four-dimensional Sp(2N) Yang-Mills theory. We find that the
Sp(2N) connection decomposes according to irreducible representations of SO(N).

</DOC>
<DOC>
<DOCNO> 83261 </DOCNO>
Novelty Detection on a Mobile Robot Using Habituation


  In this paper a novelty filter is introduced which allows a robot operating
in an un structured environment to produce a self-organised model of its
surroundings and to detect deviations from the learned model. The environment
is perceived using the rob ot's 16 sonar sensors. The algorithm produces a
novelty measure for each sensor scan relative to the model it has learned. This
means that it highlights stimuli which h ave not been previously experienced.
The novelty filter proposed uses a model of hab ituation. Habituation is a
decrement in behavioural response when a stimulus is pre sented repeatedly.
Robot experiments are presented which demonstrate the reliable o peration of
the filter in a number of environments.

</DOC>
<DOC>
<DOCNO> 10854 </DOCNO>
Localization of acoustic waves in 1D random liquid media


  We study acoustic propagation in one dimensional water ducts containing many
air-filled blocks. The acoustic band structures for the periodic arrangements
of the blocks is calculated, whereas the transmission for various random
configurations of the blocks is computed by the transfer matrix method. It is
shown that waves at all frequencies become localized even with a small amount
of randomness. The spatial distribution of the localized energy is
investigated, and is shown not to be trapped near the source, contrary to
higher dimensional cases. The results also reveal a distinct collective
behaviour for localized waves, a feature useful for distinguishing the
localization from the residual absorption effect.

</DOC>
<DOC>
<DOCNO> 101125 </DOCNO>
Arakelov-type inequalities for Hodge bundles


  We give a proof of generalizations of the classical Arakelov inequality valid
for the degree $d$ of the relative canoincal bundle of a family of curves of
genus $g$ over a complete curve of genus $p$ under the assumption that the
monodromy around the singular fibers is unipotent. This relative canonical
bundle is the (canonical extension of) the Hodge bundle and the inequality is
generalized to the degrees of the Hodge bundles of a complex variation of Hodge
structures.

</DOC>
<DOC>
<DOCNO> 72147 </DOCNO>
In Pursuit of New Physics with B_s Decays


  The presence of a sizeable CP-violating phase in B_s^0-B_s^0-bar mixing would
be an unambiguous signal of physics beyond the Standard Model. We analyse
various possibilities to detect such a new phase considering both tagged and
untagged decays. The effects of a sizeable width difference Delta Gamma between
the B_s mass eigenstates, on which the untagged analyses rely, are included in
all formulae. A novel method to find this phase from simple measurements of
lifetimes and branching ratios in untagged decays is proposed. This method does
not involve two-exponential fits, which require much larger statistics. For the
tagged decays, an outstanding role is played by the observables of the
time-dependent angular distribution of the B_s -> J/psi [-> l^+ l^-] \phi [->
K^+K^-] decay products. We list the formulae needed for the angular analysis in
the presence of both a new CP-violating phase and a sizeable Delta Gamma, and
propose methods to remove a remaining discrete ambiguity in the new phase. This
phase can therefore be determined in an unambiguous way.

</DOC>
<DOC>
<DOCNO> 120101 </DOCNO>
Extrasolar Planets and the Rotation and Axisymmetrical mass loss of


  I examine the implications of the recently found extrasolar planets on the
planet-induced axisymmetrical mass loss model for the formation of elliptical
planetary nebulae (PNs). This model, which was developed in several earlier
papers by the author and a few collaborators, attributes low departure from
spherical mass loss of upper asymptotic giant branch (AGB) stars to envelope
rotation which results from deposition of planet's orbital angular momentum. It
was predicted that about 50 percent of all sun-like stars have Jupiter-like
planets around them. In light of the new finding that only 5 percent of
sun-like stars do have such planets I revise this prediction. I now predict
that indeed about 50 percent of PNs progenitors do have close planets around
them, but the planets can have much lower masses, as low as 0.01 times
Jupiter's mass. To support this claim I follow the angular momentum evolution
of single stars as they evolve to the post-AGB phase. The prediction that on
average several such planets orbit each star, as in the solar system, still
holds.

</DOC>
<DOC>
<DOCNO> 117650 </DOCNO>
The Fluence Duration Bias


  The fluence duration bias causes fluences and durations of faint gamma-ray
bursts to be systematically underestimated relative to their peak fluxes. Using
Monte Carlo analysis, we demonstrate how this effect explains characteristics
of structure of the fluence vs. 1024 ms peak flux diagram. Evidence of this
bias exists in the BATSE fluence duration database, and provides a partial
explanation for the existence of burst class properties.

</DOC>
<DOC>
<DOCNO> 10547 </DOCNO>
Nodal Liquids and Duality


  Using a SU(2)x U(1) gauge theory for a t-J model around a node of the Fermi
surface, we discuss patterns of dynamical symmetry breaking, which may lead to
a pseudogap phase and to the appearance of narrow one-dimensional spatial
structures, induced by the presence of holes. A possible connection with stripe
phases is briefly discussed by passing to an appropriate dual theory. We
discuss confinement properties of spinons and holons and derive the spectrum of
the (gapful) physical excitations which are composites of holons corresponding
to `mesons', and composites of spinons corresponding to `baryons'.

</DOC>
<DOC>
<DOCNO> 70809 </DOCNO>
Color Superconductivity in Compact Stars


  After a brief review of the phenomena expected in cold dense quark matter,
color superconductivity and color-flavor locking, we sketch some implications
of recent developments in our understanding of cold dense quark matter for the
physics of compact stars. We give a more detailed summary of our recent work on
crystalline color superconductivity and the consequent realization that (some)
pulsar glitches may originate in quark matter.

</DOC>
<DOC>
<DOCNO> 68556 </DOCNO>
Two-loop Yang-Mills theory in the world-line formalism and an


  Within the framework of the world-line formalism we write down in detail a
two-loop Euler-Heisenberg type action for gluon loops in Yang-Mills theory and
discuss its divergence structure. We exactly perform all the world-line moduli
integrals at two loops by inserting a mass parameter, and then extract
divergent coefficients to be renormalized.

</DOC>
<DOC>
<DOCNO> 14128 </DOCNO>
Josephson Junctions with Minimal Length


  The minimal length of ``one-dimensional'' Josephson junctions, in which the
specific bound states of the magnetic flux retain their stability is discussed
numerically. Thereby, we consider as ``long'' every Josephson junction, in
which there exists at least one nontrivial stable distribution of the magnetic
flux for fixed values of all the physical and the geometrical parameters.
  Our results can be applied for optimization of the sizes of devices
containing Josephson junctions for different operating conditions.

</DOC>
<DOC>
<DOCNO> 84759 </DOCNO>
Renormalization Group Approach to Cosmological Back Reaction Problems


  We investigated the back reaction of cosmological perturbations on the
evolution of the universe using the second order perturbation of the Einstein's
equation. To incorporate the back reaction effect due to the inhomogeneity into
the framework of the cosmological perturbation, we used the renormalization
group method. The second order zero mode solution which appears by the
non-linearities of the Einstein's equation is regarded as a secular term of the
perturbative expansion, we renormalized a constant of integration contained in
the background solution and absorbed the secular term to this constant. For a
dust dominated universe, using the second order gauge invariant quantity, we
derived the renormalization group equation which determines the effective
dynamics of the Friedman-Robertson-Walker universe with the back reaction
effect in a gauge invariant manner. We obtained the solution of the
renormalization group equation and found that perturbations of the scalar mode
and the long wavelength tensor mode works as positive spatial curvature, and
the short wavelength tensor mode as radiation fluid.

</DOC>
<DOC>
<DOCNO> 101872 </DOCNO>
The identity is the most likely exchange shuffle for large n


  Let a deck of n cards be shuffled by successively exchanging the cards in
positions 1, 2, ..., n with cards in randomly chosen positions. We show that
for n equal to 18 or greater, the identity permutation is the most likely. We
prove a surprising symmetry of the resulting distribution on permutations. We
also obtain the limiting distribution of the number of fixed points as n goes
to infinity.

</DOC>
<DOC>
<DOCNO> 174575 </DOCNO>
Strange mesons in dense nuclear matter


  Experimental data on the production of kaons and antikaons in heavy ion
collisions at relativistic energies are reviewed with respect to in-medium
effects. The $K^-/K^+$ ratios measured in nucleus-nucleus collisions are 1 - 2
orders of magnitude larger than in proton-proton collisions. The azimuthal
angle distributions of $K^+$ mesons indicate a repulsive kaon-nucleon
potential. Microscopic transport calculations consistently explain both the
yields and the emission patterns of kaons and antikaons when assuming that
their properties are modified in dense nuclear matter. The $K^+$ production
excitation functions measured in light and heavy collision systems provide
evidence for a soft nuclear equation-of-state.

</DOC>
<DOC>
<DOCNO> 122355 </DOCNO>
Summary: ZeV Air Showers. Where do we Stand?


  Here an attempt is made at summarizing the presentations, most of which were
about the highest energy particles observed in nature. Particular attention is
paid to the solutions to the Ultra High Energy Cosmic Ray particles, to the new
and forthcoming data, to the new proposals for experiments and to the role of
primary composition, that were amongst the most discussed subtopics.

</DOC>
<DOC>
<DOCNO> 174535 </DOCNO>
Entropy of thermal quasiparticles in nuclei


  Information on level density for nuclei with mass numbers A = 20 - 250 is
deduced from discrete low-lying levels and neutron resonance data. The odd-mass
nuclei exhibit in general 4 - 7 times the level density found for its
neighboring even-even nuclei at the same excitation energy. This excess
corresponds to an entropy of approx. 1.7 k for the odd particle. The value is
approximately constant for all mid-shell nuclei and for all ground state spins.
For these nuclei it is argued that the entropy scales with the number of
quasiparticles. A simple model based on the canonical ensemble theory accounts
qualitatively for the observed properties.

</DOC>
<DOC>
<DOCNO> 122597 </DOCNO>
Nonlinear evolution of r-modes in rotating relativistic stars


  A numerical study of nonlinear r-modes in isentropic, rapidly rotating
relativistic stars, via 3-D general-relativistic hydrodynamical evolutions, is
presented. On dynamical timescales, we find no evidence for strong coupling of
r-modes to other modes at amplitudes of order one or larger. Therefore, unless
nonlinear saturation sets in on longer timescales, the maximum r-mode amplitude
is of order one. An absolute upper limit on the amplitude is set by causality.
Our simulations also show that r-modes and inertial modes in isentropic stars
are discrete modes, with no evidence for the existence of a continuous part in
the spectrum.

</DOC>
<DOC>
<DOCNO> 8815 </DOCNO>
Structure Factor of a Lamellar Smectic Phase with Inclusions


  Motivated by numerous X-ray scattering studies of lamellar phases with
membrane proteins, amphiphilic peptides, polymers, or other inclusions, we have
determined the modifications of the classical Caille law for a smectic phase as
a function of the nature and concentration of inclusions added to it. Besides a
fundamental interest on the behavior of fluctuating systems with inclusions, a
precise characterization of the action of a given protein on a lipid membrane
(anchoring, swelling, stiffening ...) is of direct biological interest and
could be probed by way of X-ray measurements. As a first step we consider three
different couplings involving local pinching (or swelling), stiffening or tilt
of the membrane. In the first two cases we predict that independent inclusions
induce a simple renormalization of the bending and compression modulii of the
smectic phase. The X-ray experiments may also be used to probe correlations
between inclusions. Finally we show that asymmetric coupling (such as a local
tilt of the membrane) results in a modification of the usual Caille law.

</DOC>
<DOC>
<DOCNO> 119284 </DOCNO>
Ultra-strong Elelctric Fields and Vacuum Breakdown: Search for an


  In some models of $\gamma$-ray bursts super-strong electric fields ($E\sim
10^{14} {\rm statvolt cm}^{-1}$) have been surmized. Such large fields may
provide copious pair production through vacuum polarization. Here we examine
various astrophysical scenarios where huge electric field can be present. It is
shown that when the conditions for quantistic vacuum breakdown are met, pair
creation through conventional processes is likely to be always more important.
Although of great physical interest, quantum pair production seems therefore of
little astrophysical relevance.

</DOC>
<DOC>
<DOCNO> 170311 </DOCNO>
Secure quantum key distribution using squeezed states


  We prove the security of a quantum key distribution scheme based on
transmission of squeezed quantum states of a harmonic oscillator. Our proof
employs quantum error-correcting codes that encode a finite-dimensional quantum
system in the infinite-dimensional Hilbert space of an oscillator, and protect
against errors that shift the canonical variables p and q. If the noise in the
quantum channel is weak, squeezing signal states by 2.51 dB (a squeeze factor
e^r=1.34) is sufficient in principle to ensure the security of a protocol that
is suitably enhanced by classical error correction and privacy amplification.
Secure key distribution can be achieved over distances comparable to the
attenuation length of the quantum channel.

</DOC>
<DOC>
<DOCNO> 10875 </DOCNO>
Inertial effects in three dimensional spinodal decomposition of a


  The late-stage demixing following spinodal decomposition of a
three-dimensional symmetric binary fluid mixture is studied numerically, using
a thermodynamicaly consistent lattice Boltzmann method. We combine results from
simulations with different numerical parameters to obtain an unprecendented
range of length and time scales when expressed in reduced physical units. Using
eight large (256^3) runs, the resulting composite graph of reduced domain size
l against reduced time t covers 1 < l < 10^5, 10 < t < 10^8. Our data is
consistent with the dynamical scaling hypothesis, that l(t) is a universal
scaling curve. We give the first detailed statistical analysis of fluid motion,
rather than just domain evolution, in simulations of this kind, and introduce
scaling plots for several quantities derived from the fluid velocity and
velocity gradient fields.

</DOC>
<DOC>
<DOCNO> 118821 </DOCNO>
Why Are Rotating Elliptical Galaxies Less Elliptical at X-ray


  If mass and angular momentum were conserved in cooling flows associated with
luminous, slowly rotating elliptical galaxies, the inflowing hot gas would spin
up, resulting in disks of cold gas and X-ray images that are highly flattened
along the equatorial plane out to several effective radii. Such X-ray
flattening is not observed at the spatial resolution currently available to
X-ray observations. Evidently mass and angular momentum are not in fact
conserved. If cooling flows are depleted by localized radiative cooling at
numerous sites distributed throughout the flows, then disks of cooled gas do
not form and the X-ray images appear nearly circular. However, the distribution
of young stars formed from the cooled gas is still somewhat flattened relative
to the stellar light. X-ray images of galactic cooling flows can also be
circularized by the turbulent diffusion of angular momentum away from the axis
of rotation, but the effective viscosity of known processes -- stellar mass
loss, supernovae, cooling site evolution, etc. -- is insufficient to
appreciably circularize the X-ray images. Radial gradients in the interstellar
iron abundance are unaffected by the expected level of interstellar turbulence
since these gradients are continuously re-established by Type Ia supernovae.

</DOC>
<DOC>
<DOCNO> 8900 </DOCNO>
Tenfold Magnetoconductance in a Non-Magnetic Metal Film


  We present magnetoconductance (MC) measurements of homogeneously disordered
Be films whose zero field sheet conductance (G) is described by the
Efros-Shklovskii hopping law $G(T)=(2e^2/h)\exp{-(T_o/T)^{1/2}}$. The low field
MC of the films is negative with G decreasing 200% below 1 T. In contrast the
MC above 1 T is strongly positive. At 8 T, G increases 1000% in perpendicular
field and 500% in parallel field. In the simpler parallel case, we observe {\em
field enhanced} variable range hopping characterized by an attenuation of $T_o$
via the Zeeman interaction.

</DOC>
<DOC>
<DOCNO> 85204 </DOCNO>
Cosmological models with flat spatial geometry


  The imposition of symmetries or special geometric properties on submanifolds
is less restrictive than to impose them in the full space-time. Starting from
this idea, in this paper we study irrotational dust cosmological models in
which the geometry of the hypersurfaces generated by the fluid velocity is
flat, which supposes a relaxation of the restrictions imposed by the
Cosmological Principle. The method of study combines covariant and tetrad
methods that exploits the geometrical and physical properties of these models.
This procedure will allow us to determine all the space-times within this class
as well as to study their properties. Some important consequences and
applications of this study are also discussed.

</DOC>
<DOC>
<DOCNO> 99479 </DOCNO>
A Generalized Jaynes-Cummings Hamiltonian and Supersymmetric


  A class of shape-invariant bound-state problems which represent two-level
systems are introduced. It is shown that the coupled-channel Hamiltonians
obtained correspond to the generalization of the Jaynes-Cummings Hamiltonian.

</DOC>
<DOC>
<DOCNO> 9571 </DOCNO>
Quantum transport in the cylindrical nanosize silicon-based MOSFET


  A model is developed for a detailed investigation of the current flowing
through a cylindrical nanosize MOSFET with a close gate electrode. The quantum
mechanical features of the lateral charge transport are described by Wigner
distribution function which is explicitly dealing with electron scattering due
to acoustic phonons and acceptor impurities. A numerical simulation is carried
out to obtain a set of I-V characteristics for various channel lengths. It is
demonstrated that inclusion of the collision term in the numerical simulation
is important for low values of the source-drain voltage. The calculations have
further shown that the scattering leads to an increase of the electron density
in the channel thereby smoothing out the threshold kink in I-V characteristics.
An analysis of the electron phase-space distribution shows that scattering does
not prevent electrons from flowing through the channel as a narrow stream, and
that features of both ballistic and diffusive transport may be observed
simultaneously.

</DOC>
<DOC>
<DOCNO> 119955 </DOCNO>
The Multiband Photometry of the GRB Host Galaxies


  We present photometric multiband spectral energy distributions for the GRB
host galaxies: GRB 971214, GRB 970508, GRB 980613, GRB 980703 and GRB 990123
obtained with the 6-m telescope of SAO RAS. Using SEDs for the starburst
galaxies, we made estimates of K-correction values and estimated the absolute
magnitudes of the GRB host galaxies within the range of cosmological
parameters. The comparison of the broad band spectra of these galaxies with the
spectra of galaxies of different morphological types (Connolly et al, 1995, AJ,
110, 1071) shows that the GRB host galaxies are best fitted by the spectral
properties of S2-S5 averaged SEDs of starburst galaxies.

</DOC>
<DOC>
<DOCNO> 122068 </DOCNO>
XMM-Newton observation of an unusual iron line in the quasar Markarian


  XMM-Newton observations of the low luminosity, radio-quiet quasar Markarian
205 have revealed a unique iron K emission line profile. In marked contrast to
the broad and redshifted iron K line commonly seen in ASCA observations of
Seyfert 1 galaxies, we find that a substantial amount of the line flux in Mrk
205 occurs above the neutral line energy of 6.4 keV. Furthermore, we find that
the iron line emission has two distinct components, a narrow, unresolved
neutral line at 6.4 keV and a broadened line centred at 6.7 keV. We suggest
that the most likely origin of the 6.7 keV line is from X-ray reflection off
the surface of a highly ionised accretion disk, whilst the 6.4 keV component
may arise from neutral matter distant from the black hole, quite possibly in
the putative molecular torus. Overall this observation underlines the potential
of XMM-Newton for using the iron K line as a diagnostic of matter in the
innermost regions of AGN.

</DOC>
<DOC>
<DOCNO> 119736 </DOCNO>
Radio Sources in Low-Luminosity Active Galactic Nuclei. I. VLA


  We report a 0.2" resolution, 15 GHz survey of a sample of 48 low-luminosity
active galactic nuclei with the Very Large Array. Compact radio emission has
been detected in 57% (17 of 30) of LINERs and low-luminosity Seyferts, at least
15 of which have a flat to inverted radio spectrum (alpha > -0.3). The compact
radio cores are found in both type 1 (i.e. with broad Halpha) and type 2
(without broad Halpha) nuclei. The 2 cm radio power is significantly correlated
with the emission-line ([OI] lambda6300) luminosity. While the present
observations are consistent with the radio emission originating in star-forming
regions, higher resolution radio observations of 10 of the detected sources,
reported in a companion paper (Falcke et al. 2000), show that the cores are
very compact (< pc), of high brightness temperature (T(b) >= 10^8K) and
probably synchrotron self-absorbed, ruling out a starburst origin. Thus, our
results suggest that at least 50% of low-luminosity Seyferts and LINERs in the
sample are accretion powered, with the radio emission presumably coming from
jets or advection-dominated accretion flows. We have detected only 1 of 18
`transition' (i.e. LINER + HII) nuclei observed, indicating their radio cores
are significantly weaker than those of `pure' LINERs.

</DOC>
<DOC>
<DOCNO> 150401 </DOCNO>
Is Quantum Spacetime Infinite Dimensional ?


  The Stringy Uncertainty relations, and corrections thereof, were explicitly
derived recently from the New Relativity Principle that treats all dimensions
and signatures on the same footing and which is based on the postulate that the
Planck scale is the minimal length in Nature in the same vein that the speed of
light was taken as the maximum velocity in Einstein's theory of Special
Relativity. A simple numerical argument is presented which suggests that
Quantum Spacetime may very well be $infinite$ dimensional. A discussion of the
repercusions of this new paradigm in Physics is given. A truly remarkably
simple and plausible solution of the cosmological constant problem results from
the New Relativity Principle : The cosmological constant is $not$ constant, in
the same vein that Energy in Einstein's Special Relativity is observer
dependent. Finally, following El Naschie, we argue why the observed D=4 world
might just be an $average$ dimension over the infinite possible values of the
Quantum Spacetime and why the compactification mechanisms from higher to four
dimensions in String theory may not be actually the right way to look at the
world at Planck scales.

</DOC>
<DOC>
<DOCNO> 119467 </DOCNO>
The Low Surface Brightness Extent of the Fornax Cluster


  We have used a large format CCD camera to survey the nearby Fornax cluster
and its immediate environment for low luminosity low surface brightness
galaxies. Recent observations indicate that these are the most dark matter
dominated galaxies known and so they are likely to be a good tracer of the dark
matter in clusters. We have identified large numbers of these galaxies
consistent with a steep faint end slope of the luminosity function (alpha~ -2)
down to MB ~ -12. These galaxies contribute almost the same amount to the total
cluster light as the brighter galaxies and they have a spatial extent that is
some four times larger. They satisfy two of the important predictions of N-body
hierarchical simulations of structure formation using dark halos. The
luminosity (mass ?) function is steep and the mass distribution is more
extended than that defined by the brighter galaxies. We also find a large
concentration of low surface brightness galaxies around the nearby galaxy
NGC1291.

</DOC>
<DOC>
<DOCNO> 102480 </DOCNO>
On certain isomorphisms between absolute Galois groups


  Let $k$ be an algebraically closed field of characteristic zero, $F$ be an
algebraically closed extension of $k$ of transcendence degree one, and $G$ be
the group of automorphisms over $k$ of the field $F$. The purpose of this note
is to calculate the group of continuous automorphisms of $G$.

</DOC>
<DOC>
<DOCNO> 84813 </DOCNO>
Gravitational and dilaton radiation from a relativistic membrane


  Recent scenarios of the TeV-scale brane cosmology suggest a possibility of
existence in the early universe of two-dimensional topological defects:
relativistic membranes. Like cosmic strings, oscillating membranes could emit
gravitational radiation contributing to a stochastic background of
gravitational waves. We calculate dilaton and gravitational radiation from a
closed toroidal membrane excited along one homology cycle. The spectral-angular
distributions of dilaton and gravitational radiation are obtained in a closed
form in terms of Bessel's functions. The angular distributions are affected by
oscillating factors due to an interference of radiation from different segments
of the membrane. The dilaton radiation power is dominated by a few lower
harmonics of the basic frequency, while the spectrum of the gravitational
radiation contains also a substantial contribution from higher harmonics. The
radiative lifetime of the membrane is determined by its tension and depends
weakly on the ratio of two radii of the torus. Qualitatively it is equal to the
ratio of the membrane area at the maximal extension to the gravitational radius
of the membrane as a whole.

</DOC>
<DOC>
<DOCNO> 123087 </DOCNO>
Relativistic Corrections to the Sunyaev-Zel'dovich Effect for Clusters


  We have succeeded in obtaining a precision analytic fitting formula for the
exact numerical results of the relativistic corrections to the thermal
Sunyaev-Zeldovich effect for clusters of galaxies which has a 1% accuracy for
the crossover frequency region where the thermal thermal Sunyaev-Zeldovich
effect signal changes from negative to positive sign. The fitting has been
carried out for the ranges 0.020 < theta < 0.035 and 0 < X < 15, where theta=
kTe/mc^{2}, X = omega/kT0, Te is the electron temperature, omega is the angular
frequency of the photon, and T0 is the temperature of the cosmic microwave
background radiation. The overall accuracy of the fitting is better than 0.1%.
The present analytic fitting formula will be useful for accurate analyses of
the thermal Sunyaev-Zeldovich effect for clusters of galaxies.

</DOC>
<DOC>
<DOCNO> 170582 </DOCNO>
Entanglement purification of unknown quantum states


  A concern has been expressed that ``the Jaynes principle can produce fake
entanglement'' [R. Horodecki et al., Phys. Rev. A {\bf 59}, 1799 (1999)]. In
this paper we discuss the general problem of distilling maximally entangled
states from $N$ copies of a bipartite quantum system about which only partial
information is known, for instance in the form of a given expectation value. We
point out that there is indeed a problem with applying the Jaynes principle of
maximum entropy to more than one copy of a system, but the nature of this
problem is classical and was discussed extensively by Jaynes. Under the
additional assumption that the state $\rho^{(N)}$ of the $N$ copies of the
quantum system is exchangeable, one can write down a simple general expression
for $\rho^{(N)}$. We show how to modify two standard entanglement purification
protocols, one-way hashing and recurrence, so that they can be applied to
exchangeable states. We thus give an explicit algorithm for distilling
entanglement from an unknown or partially known quantum state.

</DOC>
<DOC>
<DOCNO> 84387 </DOCNO>
The binary black-hole dynamics at the third post-Newtonian order in the


  The orbital dynamics of the binary point-mass systems is ambiguous at the
third post-Newtonian order of approximation. The static ambiguity is known to
be related to the difference between the Brill-Lindquist solution and the
Misner-Lindquist solution of the time-symmetric conformally flat initial value
problem for binary black holes. The kinetic ambiguity is noticed to violate in
general the standard relation between the center-of-mass velocity and the total
linear momentum as demanded by global Lorentz invariance.

</DOC>
<DOC>
<DOCNO> 122154 </DOCNO>
Stellar winds from Massive Stars


  We review the various techniques through which wind properties of massive
stars - O stars, AB supergiants, Luminous Blue Variables (LBVs), Wolf-Rayet
(WR) stars and cool supergiants - are derived. The wind momentum-luminosity
relation (e.g. Kudritzki et al. 1999) provides a method of predicting mass-loss
rates of O stars and blue supergiants which is superior to previous
parameterizations. Assuming the theoretical sqrt(Z) metallicity dependence,
Magellanic Cloud O star mass-loss rates are typically matched to within a
factor of two for various calibrations. Stellar winds from LBVs are typically
denser and slower than equivalent B supergiants, with exceptional mass-loss
rates during giant eruptions Mdot=10^-3 .. 10^-1 Mo/yr (Drissen et al. 2001).
Recent mass-loss rates for Galactic WR stars indicate a downward revision of
2-4 relative to previous calibrations due to clumping (e.g. Schmutz 1997),
although evidence for a metallicity dependence remains inconclusive (Crowther
2000). Mass-loss properties of luminous (> 10^5 Lo) yellow and red supergiants
from alternative techniques remain highly contradictory. Recent Galactic and
LMC results for RSG reveal a large scatter such that typical mass-loss rates
lie in the range 10^-6 .. 10^-4 Mo/yr, with a few cases exhibiting 10^-3 Mo/yr.

</DOC>
<DOC>
<DOCNO> 100010 </DOCNO>
L-embedded Banach spaces and measure topology


  An L-embedded Banach spaace is a Banach space which is complemented in its
bidual such that the norm is additive between the two complementary parts. On
such spaces we define a topology, called an abstract measure topology, which by
known results coincides with the usual measure topology on preduals of finite
von Neumann algebras (like $L_1([0,1])$). Though not numerous, the known
properties of this topology suffice to generalize several results on subspaces
of $L_1([0,1])$ to subspaces of arbitrary L-embedded spaces.

</DOC>
<DOC>
<DOCNO> 120475 </DOCNO>
Near-IR Imaging of LSB Galaxies: the High and Low HI Content Cases


  Recently acquired near-IR imaging (J and Ks) of low surface brightness
galaxies is presented. The data includes 52 galaxies with log[MHI/Msolar] < 9.0
and 58 galaxies with log[MHI/Msolar] > 9.5. These galaxies have been selected
from the catalogue of Impey et al. (1996), and all of them are observable from
both hemispheres. The principal goal of this research is to investigate the
poorly understood giant and old stellar content of these galaxies. Current work
includes total and isophotal photometry, and comparison with spectrophotometric
models of galaxy evolution, including the role of age and metallicity. Already
allocated observing time at Las Campanas Observatory will provide high S/N B
and I imaging.

</DOC>
<DOC>
<DOCNO> 99890 </DOCNO>
A reconstruction of Euler data


  We apply the mirror principle of [L-L-Y] to reconstruct the Euler data
$Q=\{Q_d\}_{d\in{\tinyBbb N}\cup\{0\}}$ associated to a vector bundle $V$ on
${\smallBbb C}{\rm P}^n$ and a multiplicative class $b$. This gives a direct
way to compute the intersection number $K_d$ without referring to any other
Euler data linked to $Q$. Here $K_d$ is the integral of the cohomology class
$b(V_d)$ of the induced bundle $V_d$ on a stable map moduli space. A package
'{\tt \verb+EulerData_MP.m+}' in Maple V that carries out the actual
computation is provided. For $b$ the Chern polynomial, the computation of $K_1$
for the bundle $V=T_{\ast}{\smallBbb C}{\rm P}^2$, and $K_d$, $d=1,2,3$, for
the bundles ${\cal O}_{{\tinyBbb C}{\rm P}^4}(l)$ with $6\le l\le 10$ done
using the code are also included.

</DOC>
<DOC>
<DOCNO> 123196 </DOCNO>
Preliminary Results from the 1999 Balloon Flight of the Liquid Xenon


  LXeGRIT is a balloon-borne Compton telescope employing a large volume liquid
xenon time projection chamber (LXeTPC) as the central gamma-ray detector. It is
designed to image gamma rays in the energy range of 200 keV to 20 MeV, with an
angular resolution of about 3 degrees (1 sigma) at 2 MeV, within a
field-of-view (FOV) of about 1 sr. The detector's energy and three-dimensional
spatial resolution as measured during pre-flight calibration experiments, are
$\Delta E_\mathrm{lxe}/E=8.8% : \sqrt{1\MeV /E}$ and < 1mm RMS, respectively.
The detection efficiency for Compton events varies between 1.5% and 4%
depending on energy and event selection. We describe the instrument as flown on
May 7, 1999 and review its overall performance at balloon altitude. The launch
occurred at 13:26:54 UT from Ft. Sumner, New Mexico and the flight was
terminated about 9 hours later. The Crab was in the instrument FOV for a few
hours. Analysis of these data is in progress.

</DOC>
<DOC>
<DOCNO> 84814 </DOCNO>
A lattice quantum gravity model with surface-like excitations in


  A lattice quantum gravity model in 4 dimensional Riemannian spacetime is
constructed based on the SU(2) Ashtekar formulation of general relativity. This
model can be understood as one of the family of models sometimes called ``spin
foam models.'' A version of the action of general relativity in continuum is
introduced and its lattice version is defined. A dimensionless ``(inverse)
coupling'' constant is defined so that the value of the action of the model is
finite per lattice point. The path integral of the model is expanded in the
characters and shown to be written as a sum over surface-like excitations in
spacetime. A 3 dimensional version of the model exists and can be reduced to
lattice BF theory. The expectation values of some quantities are computed in 3
dimensions and the meanings of the results are discussed. Although the model is
studied on a hyper cubic lattice for simplicity, it can be generalized to a
randomly triangulated lattice with small modifications.

</DOC>
<DOC>
<DOCNO> 85431 </DOCNO>
A Stationary Approximation to the Spacetime of a Compact Object Binary


  The gravitational-radiation-induced inspiral of a binary system of compact
objects is considered. A scheme is described to model the regime in which the
gravitational interaction is too strong to use weak-field approximation
methods, but the time scale for decay of the orbits is still long compared to
the orbital period, by numerically solving for a stationary spacetime which
approximates the slowly evolving one. Equilibrium is to be maintained in the
radiating system by imposing a balance of incoming and outgoing radiation at
large distances. Numerical results from non-linear scalar field theory have
shown that such an approach can be effective modelling a slowly evolving
solution to a wave equation.

</DOC>
<DOC>
<DOCNO> 101298 </DOCNO>
Selection of subsystems of random variables equivalent in distribution


  We present necessary and sufficient conditions on systems of random variables
for them to possess a lacunary subsystem equivalent in distribution to the
Rademacher system on the segment [0,1]. In particular, every uniformly bounded
orthonormal system has this property. Furthermore, an arbitrary finite
uniformly bounded orthonormal set of N functions contains a subset of
"logarithmic" density equivalent in distribution to the corresponding set of
Rademacher functions, with a constant independent of N. A connection between
the tail distribution and the L_p-norms of polynomials with respect to systems
of random variables exploited. We use also these results to study K-closed
representability of some Banach couples.

</DOC>
<DOC>
<DOCNO> 169822 </DOCNO>
Private Quantum Channels and the Cost of Randomizing Quantum Information


  We investigate how a classical private key can be used by two players,
connected by an insecure one-way quantum channel, to perform private
communication of quantum information. In particular we show that in order to
transmit n qubits privately, 2n bits of shared private key are necessary and
sufficient. This result may be viewed as the quantum analogue of the classical
one-time pad encryption scheme. From the point of view of the eavesdropper,
this encryption process can be seen as a randomization of the original state.
We thus also obtain strict bounds on the amount of entropy necessary for
randomizing n qubits.

</DOC>
<DOC>
<DOCNO> 151362 </DOCNO>
Solitonic sectors, alpha-induction and symmetry breaking boundaries


  We develop a systematic approach to boundary conditions that break bulk
symmetries in a general way such that left and right movers are not necessarily
connected by an automorphism. In the context of string compactifications, such
boundary conditions typically include non-BPS branes. Our formalism is based on
two dual fusion rings, one for the bulk and one for the boundary fields. Only
in the Cardy case these two structures coincide. In general they are related by
a version of alpha-induction. Symmetry breaking boundary conditions correspond
to solitonic sectors. In examples, we compute the annulus amplitudes and
boundary states.

</DOC>
<DOC>
<DOCNO> 101567 </DOCNO>
Hamiltonian symplectomorphisms and the Berry phase


  On the space ${\cal L}$, of loops in the group of Hamiltonian
symplectomorphisms of a symplectic quantizable manifold, we define a closed
${\bf Z}$-valued 1-form $\Omega$. If $\Omega$ vanishes, the prequantization map
can be extended to a group representation. On ${\cal L}$ one can define an
action integral as an ${\bf R}/{\bf Z}$-valued function, and the cohomology
class $[\Omega]$ is the obstruction to the lifting of that action integral to
an ${\bf R}$-valued function. The form $\Omega$ also defines a natural grading
on $\pi_1({\cal L})$.

</DOC>
<DOC>
<DOCNO> 100696 </DOCNO>
Field Theory on the q-deformed Fuzzy Sphere I


  We study the q-deformed fuzzy sphere, which is related to D-branes on SU(2)
WZW models, for both real q and q a root of unity. We construct for both cases
a differential calculus which is compatible with the star structure, study the
integral, and find a canonical frame of one-forms. We then consider actions for
scalar field theory, as well as for Yang-Mills and Chern-Simons-type gauge
theories. The zero curvature condition is solved.

</DOC>
<DOC>
<DOCNO> 118045 </DOCNO>
Search for molecular gas in HVCs through HCO+ absorption


  High-Velocity Clouds (HVCs) have radial velocities that cannot be explained
by the global Galactic rotation; their distances remain mostly unknown, and
their true nature and origin are still a mystery. Some of them could be of
galactic origin, or belong to tidal streams drawn by the Milky-Way/ Magellanic
Clouds interaction, or could even be intergalactic clouds infalling onto the
Local Group. In the latter hypothesis, they play a major role in the
hierarchical formation scenario of the Milky-Way and are connected to the
Lyman-limit absorption systems. In any case, the determination of their
physical state (density, temperature, internal structure, abundances,
excitation) will help to discriminate between current theories on their origin
and nature. A recent UV measurement (Richter et al 1999) has discovered for the
first time in a HVC the molecular phase that was previously searched for,
without success, through CO emission. Previous non detections could be due
either to metallicity problems, or insufficient excitation (because of low
density). Low-excitation molecular gas may, however, be detectable though
absorption. Here we report on a sensitive search for HCO+(1-0) absorption lines
in front of 27 quasars, already known to be strong millimetric continuum
sources. Except for one tentative case, no detection was obtained in most HVCs,
although HCO+(1-0) was clearly detected towards galactic low-velocity clouds.
We discuss the implications of this result.

</DOC>
<DOC>
<DOCNO> 84380 </DOCNO>
Black Hole Decay and Quantum Instantons


  We study the analytic structure of the S-matrix which is obtained from the
reduced Wheeler-DeWitt wave function describing spherically symmetric
gravitational collapse of massless scalar fields. The complex simple poles in
the S-matrix lead to the wave functions that satisfy the same boundary
condition as quasi-normal modes of a black hole, and correspond to the bounded
states of the Euclidean Wheeler-DeWitt equation. These wave function are
interpreted as quantum instantons.

</DOC>
<DOC>
<DOCNO> 9745 </DOCNO>
Numerical study of the spherically-symmetric Gross-Pitaevskii equation


  We present a numerical study of the time-dependent and time-independent
Gross-Pitaevskii (GP) equation in two space dimensions, which describes the
Bose-Einstein condensate of trapped bosons at ultralow temperature with both
attractive and repulsive interatomic interactions. Both time-dependent and
time-independent GP equations are used to study the stationary problems. In
addition the time-dependent approach is used to study some evolution problems
of the condensate. Specifically, we study the evolution problem where the trap
energy is suddenly changed in a stable preformed condensate. In this case the
system oscillates with increasing amplitude and does not remain limited between
two stable configurations. Good convergence is obtained in all cases studied.

</DOC>
<DOC>
<DOCNO> 121590 </DOCNO>
VLBA Observations Of A Sample Of Nearby FR I Radio Galaxies


  We observed 17 nearby low luminosity FR I radio galaxies using the NRAO Very
Long Baseline Array (VLBA) at 1.67 GHz, as part of a multi-wavelength study of
a complete sample of 21 sources selected by radio flux density from the Uppsala
General Catalogue of Galaxies. We detected radio emission from all 17 galaxies.
At a FWHM resolution of ~ 10x4 mas, five galaxies show only an unresolved radio
core, ten galaxies show core-jet structures, and two galaxies show twin-jet
structures. Comparing these VLBA images with images previously obtained with
the NRAO VLA, we find that all detected VLBA jets are well-aligned on parsec
scales with the VLA jets on kilo parsec scales, and that the jet to counter-jet
surface brightness ratios, or the sidedness, decreases systematically with
increasing distance along the jet. We attribute the sidedness to the Doppler
boosting effect and its decline to the deceleration of the jets. We show that a
distribution of Lorentz factor centered near Gamma = 5 can reproduce our VLBA
detection statistics for core, core-jet and twin-jet sources. We also note that
the luminosity per unit length, L_j, of the VLBA jets drops quickly with
distance, r, along the jet, approximately as L_j being proportional to
r^(-2.0). We discuss three different mechanisms to explain this jet fading: (1)
the decrease of Doppler boosting due to jet deceleration, (2) synchrotron
losses, and (3) expansion losses in constant velocity but adiabatically
spreading jets. Mechanisms (1) and (2) are inconsistent with the observations,
while mechanism (3) is consistent with the observations provided the magnetic
field lines in the jets are aligned perpendicular to the jet axis. This implies
that the deceleration of the jets required by the Unified Scheme does not occur
on the tens of parsec scales, but must occur on larger scales.

</DOC>
<DOC>
<DOCNO> 12663 </DOCNO>
Pressure Dependence of the Barrier Height in Tunnel n-GaAs/Au Junctions


  The theory of tunnel current-voltage (I-V) characteristics of
metal-semiconductor junctions based on the self-consistent solution of Poisson
equation allows to get the Schottky-barrier height and the charged impurity
concentration directly from the tunneling data. This approach was applied to
the analysis of the low temperature experiments on tunneling under pressure up
to 3 GPa in a piston-cylinder gauge. Here we present the barrier height versus
pressure for heavily doped tunnel junctions and compare the obtained pressure
dependence of the Schottky barrier with known behavior of the band gap under
pressure taking into account the influence of the L- and X-valleys and DX
centers.

</DOC>
<DOC>
<DOCNO> 116318 </DOCNO>
Dynamics of Atom-Mediated Photon-Photon Scattering II: Experiment


  Temporal and angular correlations in atom-mediated photon-photon scattering
are measured. Good agreement is found with the theory presented in Part~I.

</DOC>
<DOC>
<DOCNO> 83277 </DOCNO>
Dialogue Act Modeling for Automatic Tagging and Recognition of


  We describe a statistical approach for modeling dialogue acts in
conversational speech, i.e., speech-act-like units such as Statement, Question,
Backchannel, Agreement, Disagreement, and Apology. Our model detects and
predicts dialogue acts based on lexical, collocational, and prosodic cues, as
well as on the discourse coherence of the dialogue act sequence. The dialogue
model is based on treating the discourse structure of a conversation as a
hidden Markov model and the individual dialogue acts as observations emanating
from the model states. Constraints on the likely sequence of dialogue acts are
modeled via a dialogue act n-gram. The statistical dialogue grammar is combined
with word n-grams, decision trees, and neural networks modeling the
idiosyncratic lexical and prosodic manifestations of each dialogue act. We
develop a probabilistic integration of speech recognition with dialogue
modeling, to improve both speech recognition and dialogue act classification
accuracy. Models are trained and evaluated using a large hand-labeled database
of 1,155 conversations from the Switchboard corpus of spontaneous
human-to-human telephone speech. We achieved good dialogue act labeling
accuracy (65% based on errorful, automatically recognized words and prosody,
and 71% based on word transcripts, compared to a chance baseline accuracy of
35% and human accuracy of 84%) and a small reduction in word recognition error.

</DOC>
<DOC>
<DOCNO> 12312 </DOCNO>
Conductance Fluctuations of Generic Billiards: Fractal or Isolated?


  We study the signatures of a classical mixed phase space for open quantum
systems. We find the scaling of the break time up to which quantum mechanics
mimics the classical staying probability and derive the distribution of
resonance widths. Based on these results we explain why for mixed systems two
types of conductance fluctuat ions were found: quantum mechanics divides the
hierarchically structured chaotic component of phase space into two parts - one
yields fractal conductance fluctuations while the other causes isolated
resonances. In general, both types appear together, but on different energy
scales.

</DOC>
<DOC>
<DOCNO> 150502 </DOCNO>
On the nonlinear KK reductions on spheres of supergravity theories


  We address some issues related to the construction of general Kaluza-Klein
(KK) ans\"atze for the compactification of a supergravity (sugra) theory on a
sphere $S_m$. We first reproduce various ans\"atze for compactification to 7d
from the ansatz for the full nonlinear KK reduction of 11d sugra on
$AdS_7\times S_4$. As a side result, we obtain a lagrangian formulation of 7d
${\cal N}=2$ gauged sugra, which so far had only a on-shell formulation,
through field equations and constraints. The $AdS_7\times S_4$ ansatz
generalizes therefore all previous sphere compactifications to 7d. Then we
consider the case when the scalars in the lower dimensional theory are in a
coset $Sl(m+1)/SO(m+1)$, and we keep the maximal gauge group $SO(m+1)$. The
11-dimensional sugra truncated on $S_4$ fits precisely the case under
consideration, and serves as a model for our construction. We find that the
metric ansatz has a universal expression, with the internal space deformed by
the scalar fluctuations to a conformally rescaled ellipsoid. We also find the
ansatz for the dependence of the antisymmetric tensor on the scalars. We
comment on the fermionic ansatz, which will contain a matrix $U$ interpolating
between the spinorial $SO(m+1)$ indices of the spherical harmonics and the
$R$-symmetry indices of the fermionic fields in the lower dimensional sugra
theory. We derive general conditions which the matrix $U$ has to satisfy and we
give a formula for the vielbein in terms of $U$. As an application of our
methods we obtain the full ansatz for the metric and vielbein for 10d sugra on
$AdS_5\times S_5$ (with no restriction on any fields).

</DOC>
<DOC>
<DOCNO> 116771 </DOCNO>
Cosmic Acceleration: A Natural Remedy For Horizon and Flatness Problems


  The standard big bang cosmology has been greatly successful in explaining
many observational aspects of the real universe. However, two particular
diffficulties faced by it are the so-called ``horizon'' and ``flatness''
problems. By assuming that the recently found cosmic acceleration to be a
genuine and ever present effect, we show that, the resultant modified Friedman
model is free from both the above referred problems, and there is no need to
invoke the additional ``inflationary'' initial phase as a seperate ingredient.
The important cosmological milestones of the standard big babg cosmology (which
predicts cosmic deceleration) like GUT symmetry breaking epoch or radiation
matter decoupling epoch may remain more or less unchanged in the modified
cosmology in terms of redshift values. However, in terms of cosmic time $t$,
all such epochs occur earlier as the universe becomes older in this case.

</DOC>
<DOC>
<DOCNO> 69462 </DOCNO>
DIS structure functions from the saturation model


  We present a description of inclusive and diffractive structure functions in
DIS at small $x$, using a model based on high energy factorization. In this
model the two processes have physical interpretation in terms of the virtual
photon wave function and the dipole cross section. We postulate the dipole
cross section form in a way in which unitarity is taken into account. A good
description of data (including DIS diffraction) is obtained after determining
three parameters of the dipole cross section from the fit to inclusive data
only.

</DOC>
<DOC>
<DOCNO> 84940 </DOCNO>
Radiation-reaction force on a particle plunging into a black hole


  We calculate the self force acting on a scalar particle which is falling
radially into a Schwarzschild black hole. We treat the particle's self-field as
a linear perturbation over the fixed Schwarzschild background. The force is
calculated by numerically solving the appropriate wave equation for each mode
of the field in the time domain, calculating its contribution to the self
force, and summing over all modes using Ori's mode-sum regularization
prescription. The radial component of the force is attractive at large
distances, and becomes repulsive as the particle approaches the event horizon.

</DOC>
<DOC>
<DOCNO> 8563 </DOCNO>
Charge-Reversal Instability in Mixed Bilayer Vesicles


  Bilayer vesicles form readily from mixtures of charged and neutral
surfactants. When such a mixed vesicle binds an oppositely-charged object, its
membrane partially demixes: the adhesion zone recruits more charged surfactants
from the rest of the membrane. Given an unlimited supply of adhering objects
one might expect the vesicle to remain attractive until it was completely
covered. Contrary to this expectation, we show that a vesicle can instead
exhibit {\it adhesion saturation,} partitioning spontaneously into an
attractive zone with definite area fraction, and a repulsive zone. The latter
zone rejects additional incoming objects because counterions on the interior of
the vesicle migrate there, effectively reversing the membrane's charge. The
effect is strongest at high surface charge densities, low ionic strength, and
with thin, impermeable membranes. Adhesion saturation in such a situation has
recently been observed experimentally [H. Aranda-Espinoza {\it et al.}, {\sl
Science} {\bf285} 394--397 (1999)].

</DOC>
<DOC>
<DOCNO> 12651 </DOCNO>
Finite-wavevector Jahn-Teller-pairing and superconductivity in the


  A model interaction is proposed in which pairing is caused by a non-local
Jahn-Teller (JT) -like instability due to the coupling between planar O states
and knot equal to 0 phonons. Apart from pairing, the interaction is found to
naturally allow metallic stripe formation. The consequences of the model for
superconductivity in the cuprates are discussed. The model is shown to be
consistent with numerous sets of experimental data in quite some detail.

</DOC>
<DOC>
<DOCNO> 102634 </DOCNO>
Flattening and subanalytic sets in rigid analytic geometry


  Let $K$ be an algebraically closed field endowed with a complete
non-archimedean norm with valuation ring $R$. Let $f\colon Y\to X$ be a map of
$K$-affinoid varieties. In this paper we study the analytic structure of the
image $f(Y)\subset X$; such an image is a typical example of a subanalytic set.
Using Embedded Resolution of Singularities, we derive in the zero
characteristic case a Uniformization Theorem for subanalytic sets: after
finitely many local blowing ups with smooth centres, a subanalytic set becomes
semi-analytic. To prove this we establish a Flattening Theorem for affinoid
varieties in the style of Hironaka, which allows a reduction to the study of
subanalytic sets arising from flat maps. Specifically we show that a map of
affinoid varieties can be rendered flat by using only finitely many local
blowing ups. The case of an image under a flat map is then dealt with by a
small extension of a result of Raynaud.
  Our result can be conveniently stated as a Quantifier Elimination theorem for
the valuation ring $R$ in an analytic expansion of the language of valued
fields. This formulation is in the style of Denef and van den Dries.

</DOC>
<DOC>
<DOCNO> 10019 </DOCNO>
Electronic structure of Co_xTiSe_2 and Cr_xTiSe_2


  The results of investigations of intercalated compounds Cr_xTiSe_2 and
Co_xTiSe_2 by X-ray photoelectron spectroscopy (XPS) and X-ray emission
spectroscopy (XES) are presented. The data obtained are compared with
theoretical results of spin-polarized band structure calculations. A good
agreement between theoretical and experimental data for the electronic
structure of the investigated materials has been observed. The interplay
between the M3d--Ti3d hybridization (M=Cr, Co) and the magnetic moment at the M
site is discussed. A 0.9 eV large splitting of the core Cr2p{3/2} level was
observed, which reveals a strong exchange magnetic interaction of 3d-2p
electrons of Cr. In the case of a strong localization of the Cr3d electrons
(for x<0.25), the broadening of the CrL spectra into the region of the states
above the nominal Fermi level was observed and attributed to X-ray re-emission.
The measured kinetic properties are in good accordance with spectral
investigations and band calculation results.

</DOC>
<DOC>
<DOCNO> 100167 </DOCNO>
Symmetry reduction of discrete Lagrangian mechanics on Lie groups


  For a discrete mechanical system on a Lie group $G$ determined by a (reduced)
Lagrangian $\ell$ we define a Poisson structure via the pull-back of the
Lie-Poisson structure on the dual of the Lie algebra ${\mathfrak g}^*$ by the
corresponding Legendre transform. The main result shown in this paper is that
this structure coincides with the reduction under the symmetry group $G$ of the
canonical discrete Lagrange 2-form $\omega_\mathbb{L}$ on $G \times G$. Its
symplectic leaves then become dynamically invariant manifolds for the reduced
discrete system. Links between our approach and that of groupoids and
algebroids as well as the reduced Hamilton-Jacobi equation are made. The rigid
body is discussed as an example.

</DOC>
<DOC>
<DOCNO> 69290 </DOCNO>
Energy loss and $x_2$ scaling breakdown in $J/\psi$ nuclear production


  In addition to the final-state interactions, $J/\psi$ nuclear production
might also be affected by parton energy loss. Using the upper limits from
Drell-Yan data at SPS and Fermilab energies, we estimated energy loss
contribution to $J/\psi$ production in p-A collisions. The results indicated
that the effects might be sizeable at 200 GeV while remaining small at higher
energies.

</DOC>
<DOC>
<DOCNO> 178500 </DOCNO>
Double giant dipole resonances in time-dependent density-matrix theory


  The strength functions of the DGDRs in 16O and 40Ca are calculated using an
extended version of TDHF known as the time-dependent density-matrix theory
(TDDM). The calculations are done in a self-consistent manner, in which the
same Skyrme force as that used for the mean-field potential is used as the
residual interaction to calculate two-body correlations. It is found that the
DGDR in 16O has a large width due to the Landau damping, although the centroid
energy of the DGDR is close to twice the energy of the GDR calculated in RPA.
The DGDR in 40Ca is found more harmonic than that in 16O.

</DOC>
<DOC>
<DOCNO> 13264 </DOCNO>
Direct observation of growth and collapse of a Bose-Einstein condensate


  The dynamical behavior of Bose-Einstein condensation (BEC) in a gas with
attractive interactions is striking. Quantum theory predicts that BEC of a
spatially homogeneous gas with attractive interactions is precluded by a
conventional phase transition into either a liquid or solid. When confined to a
trap, however, such a condensate can form provided that its occupation number
does not exceed a limiting value. The stability limit is determined by a
balance between self-attraction and a repulsion arising from position-momentum
uncertainty under conditions of spatial confinement. Near the stability limit,
self-attraction can overwhelm the repulsion, causing the condensate to
collapse. Growth of the condensate, therefore, is punctuated by intermittent
collapses, which are triggered either by macroscopic quantum tunneling or
thermal fluctuation. Previous observation of growth and collapse has been
hampered by the stochastic nature of these mechanisms. Here we reduce the
stochasticity by controlling the initial number of condensate atoms using a
two-photon transition to a diatomic molecular state. This enables us to obtain
the first direct observation of the growth of a condensate with attractive
interactions and its subsequent collapse.

</DOC>
<DOC>
<DOCNO> 118318 </DOCNO>
A Model of Supernovae Feedback in Galaxy Formation


  A model of supernovae feedback during disc galaxy formation is developed. The
model incorporates infall of cooling gas from a halo and outflow of hot gas
from a multiphase interstellar medium and a self-regulated model for star
formation. Hot gas is created by thermal evaporation of cold gas clouds in
supernovae remnants, and criteria are derived to estimate the characteristic
temperature and density of the hot component and hence the net mass outflow
rate. A number of refinements of the model are investigated, including a simple
model of a galactic fountain, the response of the cold component to the
pressure of the hot gas, pressure induced star formation and chemical
evolution. The main conclusion of this paper is that low rates of star
formation can expel a large fraction of the gas from a dwarf galaxy. Effective
feedback can therefore take place in a quiescent mode and does not require
strong bursts of star formation. Consequences for galaxy formation and damped
Ly alpha systems are discussed.

</DOC>
<DOC>
<DOCNO> 102611 </DOCNO>
Torseurs associes a certaines relations algebriques entre polyzetas aux


  We describe in this note a torsor structure arising on the affine scheme
defined by a system of rationnal algebraic relations between polyzetas at roots
of unity (values of hyperlogarithmic functions on a fixed finite group of
complex roots of unity).
  When this group is reduced to 1, we call these numbers the polyzetas. They
generalize the values of the Riemann zeta function at odd positive integers and
are also called MZVs, multizetas, multiple harmonic series or Euler/Zagier
sums. It is believed that the relations we consider here span all algebraic
relations between them. The torsor structure underlying these relations should
in that case be se same as Drinfeld's torsor made of the Grothendieck-
Teichmueller group acting on associators.
  The formulas for the general case are derived from the action of the absolute
Galois group on the projective line minus finitely many points. It is an easy
consequence of the torsor structure that the algebra defined by these relations
is a polynomial algebra. This was stated first by J. Ecalle in the polyzetas
case.

</DOC>
<DOC>
<DOCNO> 151537 </DOCNO>
The solution to Slavnov-Taylor identities in D4 N=1 SYM


  D4 N=1 SYM with an arbitrary chiral background superfield as the gauge
coupling is considered. The solution to Slavnov-Taylor identities has been
given. It has been shown that the solution is unique and allows us to restrict
the gauge part of the effective action. Under the effective action in this
paper we mean the 1PI diagram generator.

</DOC>
<DOC>
<DOCNO> 70168 </DOCNO>
Comparison of $k_T$-Factorization Approach and QCD Parton Model for


  We compare the numerical predictions for heavy quark production in high
energy hadron collisions of the conventional QCD parton model and the
$k_T$-factorization approach (semihard theory). The total production cross
sections, one-particle rapidity and $p_T$ distributions as well as two-particle
correlations are considered. The difference in the predictions of the two
approaches is not very large, while the shapes of the distributions are
slightly different.

</DOC>
<DOC>
<DOCNO> 10926 </DOCNO>
Sliding Phases via Magnetic Fields


  We show that three dimensional "sliding" analogs of the Kosterlitz-Thouless
phase, in stacked classical two-dimensional XY models and quantum systems of
coupled Luttinger Liquids, can be enlarged by the application of a parallel
magnetic field, which has the effect of increasing the scaling dimensions of
the most relevant operators that can perturb the critical sliding phases.
Within our renormalization group analysis, we also find that for the case of
coupled Luttinger liquids, this effect is interleaved with the onset of the
integer quantum Hall effect for weak interactions and fields. We comment on
experimental implications for a conjectured smectic metal phase in the
cuprates.

</DOC>
<DOC>
<DOCNO> 101016 </DOCNO>
Zeros of Gaussian Analytic Functions


  We prove and discuss three results on zero distribution of gaussian analytic
functions: (i) the Edeleman-Kostlan formula for the expectation of the counting
measure; (ii) a variation on the theme of Calabi's rigidity theorem; (iii)
Offord's estimate of exponential decay of the tail probabilities of an anlytic
function having an access or deficiency of zeros in a given region.

</DOC>
<DOC>
<DOCNO> 99531 </DOCNO>
Symplectic Lefschetz fibrations on S^1 x M^3


  In this paper we classify symplectic Lefschetz fibrations (with empty base
locus) on a four-manifold which is the product of a three-manifold with a
circle. This result provides further evidence in support of the following
conjecture regarding symplectic structures on such a four-manifold: if the
product of a three-manifold with a circle admits a symplectic structure, then
the three-manifold must fiber over a circle, and up to a self-diffeomorphism of
the four-manifold, the symplectic structure is deformation equivalent to the
canonical symplectic structure determined by the fibration of the
three-manifold over the circle.

</DOC>
<DOC>
<DOCNO> 13056 </DOCNO>
D-Wave Superconductors near Surfaces and Interfaces: A Scattering Matrix


  A recently developed method [A. Shelankov and M. Ozana, Phys. Rev. B 61, 7077
(2000)] is applied to investigate d-wave superconductors in the vicinity of
(rough) surfaces. While this method allows the incorporation of arbitrary
interfaces into the quasiclassical technique, we discuss, as examples,
diffusive surfaces and boundaries with small tilted mirrors (facets). The
properties of the surface enter via the scattering matrix in the boundary
condition for the quasiclassical Green's function. The diffusive surface is
described by an ensemble of random scattering matrices. We find that the
fluctuations of the density of states around the average are small; the zero
bias conductance peak broadens with increasing disorder. The faceted surface is
described in the model where the scattering matrix couples m in- and m
out-trajectories (m>=2). No zero bias conductance peak is found for [100]
surfaces; the relation to the model of Fogelstrom et al. [Phys. Rev. Lett. 79,
281 (1997)] is discussed.

</DOC>
<DOC>
<DOCNO> 85487 </DOCNO>
Radiation Pressure Induced Instabilities in Laser Interferometric


  The large scale interferometric gravitational wave detectors consist of
Fabry-Perot cavities operating at very high powers ranging from tens of kW to
MW for next generations. The high powers may result in several nonlinear
effects which would affect the performance of the detector. In this paper, we
investigate the effects of radiation pressure, which tend to displace the
mirrors from their resonant position resulting in the detuning of the cavity.
We observe a remarkable effect, namely, that the freely hanging mirrors gain
energy continuously and swing with increasing amplitude. It is found that the
`time delay', that is, the time taken for the field to adjust to its
instantaneous equilibrium value, when the mirrors are in motion, is responsible
for this effect. This effect is likely to be important in the optimal operation
of the full-scale interferometers such as VIRGO and LIGO.

</DOC>
<DOC>
<DOCNO> 119239 </DOCNO>
Periodic modulation of the optical counterpart of the X-ray pulsator


  Time-resolved observations of a 6' x 6' field, containing the position error
boxes of the X-ray source 1WGA J1958.2+3232, were performed in June 1999 with
the 91 cm Catania telescope, equipped with a Photon Counting Intensified CCD.
The star recently proposed as the optical counterpart of the 1WGA J1958.2+3232,
exhibited a strong optical modulation with a period compatible with that seen
in X-ray (~12 min). The optical modulation was detected again in September and
October 1999. These results confirm the identification of the optical
counterpart and support the classification of 1WGA J1958.2+3232 as a
cataclysmic variable, possibly an Intermediate Polar. Modulation at period
twice as large was also found in one observation run, suggesting that the true
spin period of the White Dwarf could be 24 min rather than 12 min, thus 1WGA
J1958.2+3232 appears to be, among the IPs, the slowest rotator which exhibit
double peaked spin profile.

</DOC>
<DOC>
<DOCNO> 178672 </DOCNO>
Description of Excitations in Odd Non-magic Nuclei by the Green's


  General equations for one- particle Green function in non- magic nuclei have
been derived where a pairing mechanism, which is analogous to the Bardeen-
Cooper- Schrieffer one, has been singled out explicitely. A "refining"
procedure for the phenomenological single- particle energies and pairing gaps
is formulated to avoid double counting of the phonon mixing if the initial data
of the problem are these phenomenological quantities. The general equations
obtained have been written in the squared phonon creation amplitude
approximation. This corresponds to taking quasiparticle$\otimes$phonon
configurations into account and, as shown in the work, is a good approximation
for semi- magic nuclei. Using this approximation the secular equation to
calculate excitations of odd non- magic nuclei has been obtained. The equation
takes ground state correlations into account completely and contains only the
squared energy variable. Distributions of single- particle strength in 119Sn
and 121}Sn have been calculated and reasonable agreement with the available
experiment has been obtained.

</DOC>
<DOC>
<DOCNO> 72242 </DOCNO>
Higgs description of two-flavor QCD vacuum


  A Higgs description for the QCD vacuum in the limit of two quark flavors is
proposed. Complete ``spontaneous breaking'' of color symmetry is realized by
condensation of an adjoint quark-antiquark and a quark-quark pair. The vacuum
is invariant under isospin symmetry applying color and flavor transformations
simultaneously. All elementary excitations acquire integral charges. The
dressed microscopic quark and gluon degrees of freedom can be identified with
the macroscopic baryon and vector meson degrees of freedom. In addition to the
nucleons we find soliton--type fermions with integer isospin. Their presence
provides an important test accessible to lattice QCD simulations.

</DOC>
<DOC>
<DOCNO> 122750 </DOCNO>
The Accretion-Ejection Instability in X-ray Binaries


  The Accretion-Ejection Instability (AEI), which can occur in magnetized disks
near equipartition, is a good candidate to explain the low-frequency QPO in
black-hole binaries. Here we present analytical work concerning the behavior of
QPO frequency and the emission of Alfv\'en waves from the disk to the corona.

</DOC>
<DOC>
<DOCNO> 102704 </DOCNO>
The Large Deviation Principle for Coarse-Grained Processes


  The large deviation principle is proved for a class of $L^2$-valued processes
that arise from the coarse-graining of a random field. Coarse-grained processes
of this kind form the basis of the analysis of local mean-field models in
statistical mechanics by exploiting the long-range nature of the interaction
function defining such models. In particular, the large deviation principle is
used in a companion paper to derive the variational principles that
characterize equilibrium macrostates in statistical models of two-dimensional
and quasi-geostrophic turbulence. Such macrostates correspond to large-scale,
long-lived flow structures, the description of which is the goal of the
statistical equilibrium theory of turbulence. The large deviation bounds for
the coarse-grained process under consideration are shown to hold with respect
to the strong $L^2$ topology, while the associated rate function is proved to
have compact level sets with respect to the weak topology. This compactness
property is nevertheless sufficient to establish the existence of equilibrium
macrostates for both the microcanonical and canonical ensembles.

</DOC>
<DOC>
<DOCNO> 10475 </DOCNO>
Pulling Hairpinned Polymers


  We introduce a model of thermalized conformations in space of RNA -or single
stranded DNA- molecules, which includes the possibility of hairpin formation.
This model contains the usual secondary structure information, but extends it
to the study of one element of the ternary structure, namely the end-to-end
distance. The computed force-elongation characteristics is in good agreemement
with some recent measurements on single stranded DNA molecules.

</DOC>
<DOC>
<DOCNO> 101607 </DOCNO>
Calabi flow in Riemann surfaces revisited: A new point of view


  In this paper, we observe a set of functionals of metrics which are all
decrease under the Calabi flow and have uniform lower bound along the flow,
which give rise to a set of integral estimates on the curvature flow. Using
these estimates, together with weak compactness we obtained in previous papers
[8] and [10], we prove the long term existence and convergence of the Calabi
flow. Thus give a new proof to Chruscial's theorem. The set of simple ideas of
global integral estimates and concentration compactness should have further
implications in other heat flow problems.

</DOC>
<DOC>
<DOCNO> 117941 </DOCNO>
Evidence of self-interacting cold dark matter from galactic to galaxy


  Within the framework of the cold dark matter (CDM) cosmogony, a central cusp
in the density profiles of virialized dark haloes is predicted. This prediction
disagrees with the soft inner halo mass distribution inferred from observations
of dwarf and low surface brightness galaxies, and some clusters of galaxies. By
analysing data for some of these objects, we find that the halo central density
is nearly independent of the mass from galactic to galaxy cluster scales with
an average value of around 0.02 M_sun/pc^3. We show that soft cores can be
produced in the CDM haloes by introducing a lower cut-off in the power spectra
of fluctuations and assuming high orbital thermal energies during halo
formation. However, the scale invariance of the halo central density is not
reproduced in these cases. The introduction of self-interaction in the CDM
particles offers the most attractive alternative to the core problem. We
propose gravothermal expansion as a possible mechanism to produce soft cores in
the CDM haloes with self-interacting particles. A global thermodynamical
equilibrium can explain the central density scale invariance. We find a minimum
cross section capable of establishing isothermal cores in agreement with the
observed shallow cores. If \sigma and m_x are the cross section and mass of the
dark matter particle, and v is the halo velocity dispersion, then (\sigma/m_x)
\~ 4 10^{-25} (100 km s^{-1}/v) cm^2/GeV.

</DOC>
<DOC>
<DOCNO> 40414 </DOCNO>
Electroweak Physics at NuTeV


  The NuTeV experiment at Fermilab presents a determination of the electroweak
mixing angle. High purity, large statistics samples of muon-neutrino and
muon-antineutrino events allow the use of the Paschos-Wolfenstein relation, a
technique which considerably reduces systematic errors associated with charm
production and other sources. Within the Standard Model, this measurement of
sin2thw indirectly determines the W boson mass to a precision comparable to
direct measurements from high energy e+e- and ppbar colliders. NuTeV measures
sin2thw(on-shell)=0.2253+/-0.0019(stat)+/-0.0010(syst), which implies
M_W=80.26+/-0.11 GeV. Outside the Standard Model, this result can be used to
explore the possibility of new physics; in particular, we present limits on
both neutrino oscillations and the presence of extra neutral vector gauge
bosons.

</DOC>
<DOC>
<DOCNO> 150451 </DOCNO>
Self-tuning flat domain walls in 5d gravity and string theory


  We present Poincare invariant domain wall (``3-brane'') solutions to some
5-dimensional effective theories which can arise naturally in string theory. In
particular, we find theories where Poincare invariant solutions exist for
arbitrary values of the brane tension, for certain restricted forms of the bulk
interactions. We describe examples in string theory where it would be natural
for the quantum corrections to the tension of the brane (arising from quantum
fluctuations of modes with support on the brane) to maintain the required form
of the action. In such cases, the Poincare invariant solutions persist in the
presence of these quantum corrections to the brane tension, so that no 4d
cosmological constant is generated by these modes.

</DOC>
<DOC>
<DOCNO> 8270 </DOCNO>
Observation of Partially Suppressed Shot Noise in Hopping Conduction


  We have observed shot noise in the hopping conduction of two dimensional
carriers confined in a p-type SiGe quantum well at a temperature of 4K.
Moreover, shot noise is suppressed relative to its ``classical'' value 2eI by
an amount that depends on the length of the sample and carrier density, which
was controlled by a gate voltage. We have found a suppression factor to the
classical value of about one half for a 2 $\mu$m long sample, and of one fifth
for a 5 $\mu$m sample. In each case, the factor decreased slightly as the
density increased toward the insulator-metal transition. We explain these
results in terms of the characteristic length ($\simeq 1\mu$m in our case) of
the inherent inhomogeneity of hopping transport.

</DOC>
<DOC>
<DOCNO> 118669 </DOCNO>
A Variability Study of Pre-Main Sequence Stars in the Extremely Young


  The extremely young cluster IC 348 has been monitored in the Cousins I band
with a 0.6 m telescope at Wesleyan's Van Vleck Observatory. Photometry of 150
stars was obtained on 76 images taken on 27 separate nights during the period
December, 1998, through March, 1999. As expected, spectral characteristics
largely determine the nature of a star's variability in this cluster. None of
the stars with H-alpha in absorption were found to be variables. On the other
hand, all 16 stars identified as CTTS by their H-alpha emission equivalent
widths and the majority of the 49 WTTS in the part of the cluster we monitored
showed evidence of variability. Nineteen stars were found to be periodic, with
periods ranging from 2.24 to 16.2 days and masses ranging from 0.35 to 1.1
M-sun. Seventeen of these are WTTS and the other 2 are of unknown spectral
class. The period distribution is remarkably similar to what is found in the
Orion Nebula Cluster for stars in the same mass range. Namely, it is bimodal
with peaks at 2-3 days and 7-8 days, although there are not enough periods
known to define these features significantly by the IC 348 data alone. The
three fastest rotators are also the three most massive stars in the periodic
sample.

</DOC>
<DOC>
<DOCNO> 121759 </DOCNO>
First Detection of CO in a Low Surface Brightness Galaxy


  We report on the first attempts at searching for CO in red low surface
brightness galaxies, and the first detection of molecular gas in a low surface
brightness (mu_B(0)_{obs} > 23 mag arcsec^{-2}) galaxy. Using the IRAM 30m
telescope, CO(1-0) and CO(2-1) lines were searched for in four galaxies --
P06-1, P05-5, C05-3, & C04-2. In three of the galaxies no CO was detected, to
T_{MB} ~ 1.8mK (at the 3 sigma level). In the fourth galaxy, P06-1, both lines
were detected. Comparing our findings with previous studies shows P06-1 to have
a molecular-to-atomic mass ratio considerably lower than is predicted using
theoretical models based on high surface brightness galaxy studies. This
indicates the N(H_2)/(int{T(CO)dv}) conversion factor for low surface
brightness galaxies may currently be consistently underestimated by a factor of
3 - 20.

</DOC>
<DOC>
<DOCNO> 13311 </DOCNO>
Has the nonlinear Meissner effect been observed?


  We examine recent high-precision experimental data on the magnetic field,
${\bf H}$, dependence of the penetration depth $\lambda(H)$ in
$\rm{YBa_2Cu_3O_{7-\delta}}$ (YBCO) for several field directions in the $a-b$
plane. In a new theoretical analysis that incorporates the effects of
orthorhombic symmetry, we show that the data at sufficiently high magnetic
fields and low temperatures are in quantitative agreement with the theoretical
predictions of the nonlinear Meissner effect.

</DOC>
<DOC>
<DOCNO> 102015 </DOCNO>
Some new behaviour in the deformation theory of Kleinian groups


  We present examples of hyperbolizable 3-manifolds $M$ with the following
property. Let $CC(\pi_1(M))$ denote the space of convex co-compact
representations of $\pi_1(M)$. We show that for every $K\geq 1$ there exists a
representation $\rho$ in $\bar {CC(\pi_1(M))}$ so that every $K$-quasiconformal
deformation of $\rho$ lies in the closure of every component of $CC(\pi_1(M))$.
  The examples $M$ were discovered by Anderson and Canary.

</DOC>
<DOC>
<DOCNO> 69939 </DOCNO>
Final State Interactions in $\epsilon'/\epsilon$


  Strong final state interaction (FSI) effects can play a central role in the
Standard Model prediction of weak $K\to 2\pi$ matrix elements. Here, I discuss
how FSI's affect the direct CP violation parameter $\vepp / \vep$ by solving
the Omn\`es problem for the necessary $K\to 2\pi$ amplitudes. The main results
of this analysis have been reported in a previous paper [1] and are further
discussed in Refs. [2,3]. The resulting Standard Model prediction ${Re} (\vepp
/ \vep) = (15\pm 5)\times 10^{-4}$ is in good agreement with the present
experimental world average.

</DOC>
<DOC>
<DOCNO> 13306 </DOCNO>
Magnetic properties of a new molecular-based spin-ladder system:


  We have synthesized and characterized a new spin-1/2 Heisenberg
antiferromagnetic ladder: bis 5-iodo-2-aminopyridinium tetrabromocuprate(II)
dihydrate. X-ray diffraction studies show the structure of the compound to
consist of well isolated stacked ladders and the interaction between the Cu(2+)
atoms to be due to direct Br...Br contacts. Magnetic susceptibility and
magnetization studies show the compound to be in the strong-coupling limit,
with the interaction along the rungs (J' ~ 13 K) much greater than the
interaction along the rails (J ~ 1 K). Magnetic critical fields are observed
near 8.3 T and 10.4 T, respectively, establishing the existence of the energy
gap.

</DOC>
<DOC>
<DOCNO> 117974 </DOCNO>
Signatures of Planets in the Observable Structure of Circumstellar


  Recent advances in astronomical instrumentation mean that we are now able to
image the thermal emission from the disks of dust around main sequence stars
that may be the fossil remnants of planetary formation. These observations
imply that the distribution of dust in the debris disks is neither smooth nor
symmetrical; e.g., mid-infrared images of the disk of dust around the young A0V
star HR 4796A show two lobes of emission, one of which may be ~5% brighter than
the other. The observed structure of the debris disk in the solar system, i.e.,
the zodiacal cloud, also contains asymmetries: it has an offset center of
symmetry, it is warped, and there is an asymmetric ring of dust co-orbiting
with the Earth. Since the zodiacal cloud's asymmetries have been shown to be
signatures of the gravitational perturbations of the solar system's planets, it
is hoped that it may be possible to indirectly detect extrasolar planetary
systems by their signatures in debris disk observations. This dissertation uses
the physical processes that affect the evolution of debris material in the
solar system to create a generalized model for the evolution of circumstellar
debris material. It then shows how planetary perturbations affect that
evolution, thereby causing the signatures of planets seen in the structure of
the zodiacal cloud. This model can be used to provide a quantitative
interpretation of debris disk observations, and the necessary modeling
techniques are demonstrated by their application to observations of the HR 4796
disk. As well as determining the large scale structure of the HR 4796 disk, the
modeling shows how a small body (>10 Earth mass) in the HR 4796 system that is
on an orbit with an eccentricity larger than 0.02 could be the cause of the
observed brightness asymmetry.

</DOC>
<DOC>
<DOCNO> 70960 </DOCNO>
Pattern of Lifetimes of Beauty Hadrons and Quark-Hadron Duality in Heavy


  We discuss (i) the evaluation of the expectation values of four-quark
operators assuming that the heavy quark expansion for $b$ sector converges at
the third order in $1/m_Q$, and (ii) the estimation of the duality breaking
short distance nonperturbative corrections to the parton decay rate. We finally
point out the implications of the result obtained for the assumption of
quark-hadron duality in heavy quark expansion.

</DOC>
<DOC>
<DOCNO> 123331 </DOCNO>
Protoneutron stars and neutron stars


  We find constraints on minimum and maximum mass of ordinary neutron stars
imposed by their early evolution (protoneutron star stage). We calculate models
of protoneutron stars using a realistic standard equation of state of hot,
dense matter valid for both supranuclear and subnuclear densities. Results for
different values of the nuclear incompressibility are presented.

</DOC>
<DOC>
<DOCNO> 118125 </DOCNO>
Keck Speckle Imaging of the White Dwarf G29-38: No Brown Dwarf Companion


  The white dwarf Giclas 29-38 has attracted much attention due to its large
infrared excess and the suggestion that excess might be due to a companion
brown dwarf. We observed this object using speckle interferometry at the Keck
telescope, obtaining diffraction-limited resolution (55 milliarcseconds) at K
band, and found it unresolved. Assuming the entire K band excess is due to a
single point-like companion, we place an upper limit on the binary separation
of 30 milliarcseconds, or 0.42 AU at the star's distance of 14.1 pc. This
result, combined with astroseismological data and other images of G29-38,
supports the hypothesis that the source of the near-infrared excess is not a
cool companion but a dust cloud.

</DOC>
<DOC>
<DOCNO> 116438 </DOCNO>
Spatial-temporal correlations in the process to self-organized


  A new type of spatial-temporal correlation in the process approaching to the
self-organized criticality is investigated for the two simple models for
biological evolution. The change behaviors of the position with minimum barrier
are shown to be quantitatively different in the two models. Different results
of the correlation are given for the two models. We argue that the correlation
can be used, together with the power-law distributions, as criteria for
self-organized criticality.

</DOC>
<DOC>
<DOCNO> 70317 </DOCNO>
On the n -> 0 limit of gamma_gg(a) in QCD


  We consider the n -> 0 limit of the DGLAP splitting function gamma_gg(a) at
all orders in the strong coupling constant, a, by analysing the leading order
large N_f form of the associated d-dimensional critical exponent. We show that
for unpolarized scattering the pole at n = 0 which appears in successive orders
in perturbation theory is absent in the resummed expression.

</DOC>
<DOC>
<DOCNO> 122264 </DOCNO>
Detection of nonrandom patterns in cosmological gravitational clustering


  A new method for analyzing point patterns produced by the evolution of
gravitational clustering is presented. The method is taken from the study of
molecular liquids, where it has been introduced for making a statistical
description of anisotropic distributions. The statistical approach is based on
the spherical harmonic expansion of angular correlations. A general
introduction to the method is given; a theoretical analysis shows that it is
partially connected with previous harmonic analyses applied to galaxy catalogs.
The effectiveness of the statistical analysis in quantifying clustering
morphology is illustrated by applying the statistical estimators to point
distributions produced by an ensemble of cosmological $N-$ body simulations
with a CDM spectrum. The results demonstrate that the statistical method is
able to detect anisotropies in non-random patterns, with different scales being
probed according to the expansion coefficients.

</DOC>
<DOC>
<DOCNO> 99568 </DOCNO>
An Abel ODE class generalizing known integrable classes


  A multi-parameter non-constant invariant Abel ODE class with the following
remarkable features is presented. This one class is shown to generalize, that
is, contain as particular cases, all the integrable classes presented by Abel,
Liouville and Appell, as well as all those shown in Kamke's book and various
other references. In addition, the class being presented includes other new and
fully integrable subclasses, as well as the most general parameterized class we
know of whose members can systematically be mapped into Riccati type ODEs.
Finally, many integrable members of this class can be systematically mapped
into an integrable member of a {\it different} class; leading in this way to
new integrable classes from previously known ones.

</DOC>
<DOC>
<DOCNO> 169772 </DOCNO>
Formation of ultrashort pulses with sub-Poissonian photon statistics


  A simple method for the production of ultrashort light pulses (USPs) with
suppressed photon fluctuations is considered. The method is based on self-phase
modulation (SPM) of an USP in a nonlinear medium (optical fibre) and subsequent
transmission of pulse through a dispersive optical element.

</DOC>
<DOC>
<DOCNO> 12546 </DOCNO>
Environment-independent decoherence rate in classically chaotic systems


  We study the decoherence of a one-particle system, whose classical
correpondent is chaotic, when it evolves coupled to a weak quenched
environment. This is done by analytical evaluation of the Loschmidt Echo, (i.e.
the revival of a localized density excitation upon reversal of its time
evolution), in presence of the perturbation. We predict an exponential decay
for the Loschmidt Echo with a (decoherence) rate which is asymptotically given
by the mean Lyapunov exponent of the classical system, and therefore
independent of the perturbation strength, within a given range of strengths.
Our results are consistent with recent experiments of Polarization Echoes in
nuclear magnetic resonance and preliminary numerical simulations.

</DOC>
<DOC>
<DOCNO> 116826 </DOCNO>
The "W" Particle and the Weak Force Mechanism


  A transformation mechanism is proposed for the "W" weak force IVB particle.
The W is a dense "metric" boson which catalyzes transformations by combining
reactants with virtual particle-antiparticle pairs created from the "vacuum".
Common weak force decays of leptons, mesons, and baryons are illustrated.

</DOC>
<DOC>
<DOCNO> 101621 </DOCNO>
Confidence intervals for the parameter of Poisson distribution in


  A results of numerical procedure for construction of confidence intervals for
parameter of Poisson distribution for signal in the presence of background
which has Poisson distribution with known value of parameter are presented. It
is shown that the described procedure has both Bayesian and frequentist
interpretations.

</DOC>
<DOC>
<DOCNO> 84322 </DOCNO>
Hamiltonian structure of the teleparallel formulation of GR


  We apply Dirac's Hamiltonian approach to study the canonical structure of the
teleparallel form of general relativity without matter fields. It is shown,
without any gauge fixing, that the Hamiltonian has the generalized Dirac-ADM
form, and constraints satisfy all the consistency requirements. The set of
constraints involves some extra first class constraints, which are used to find
additional gauge symmetries and clarify the gauge structure of the theory.

</DOC>
<DOC>
<DOCNO> 14054 </DOCNO>
Non local Thirring model with spin flipping interactions


  We extend a non local and non covariant version of the Thirring model in
order to describe a many-body system with spin-flipping interactions By
introducing a model with two fermion species we are able to avoid the use of
non abelian bosonization which is needed in a previous approach. We obtain a
bosonized expression for the partition function, describing the dynamics of the
collective modes of this system. By using the self-consistent harmonic
approximation we found a formula for the gap of the spin-charge excitations as
functional of arbitrary electron-electron potentials.

</DOC>
<DOC>
<DOCNO> 81014 </DOCNO>
Ginsparg-Wilson Fermions in Odd Dimensions


  The Ginsparg-Wilson relation, if written in a suitable form, can be used as a
condition for lattice Dirac operators of massless fermions also in odd
dimensions. The fermion action with such a Dirac operator is invariant under a
generalized parity transformation, which reduces to the ordinary parity
transformation in the (naive) continuum limit. The fermion measure, however,
transforms non-trivially under the generalized parity transformation, and hence
the parity anomaly arises solely from the fermion measure. The analogy to the
lattice construction of chiral gauge theories in even dimensions is clarified
by considering a dimensional reduction. We also propose a natural definition of
a lattice Chern-Simons term, which is consistent with odd dimensional
Ginsparg-Wilson fermions.

</DOC>
<DOC>
<DOCNO> 13554 </DOCNO>
Doping induced inhomogeneity in high-Tc superconductors


  Doping and disorder are inseparable in the superconducting cuprates. Assuming
the simplest possible disordered doping, we construct a semiphenomenological
model and analyze its experimental consequences. Among the affected
experimental quantities are the ARPES spectra and thermodynamic properties.
  From our model we make a prediction for the width of the local
superconducting gap distribution with the only experimentally unknown parameter
being the superconducting correlation length. Thus, our model provides a direct
way of determining the superconducting correlation length from a known
experimental gap distribution.

</DOC>
<DOC>
<DOCNO> 69524 </DOCNO>
Talk on fermion masses and mixings


  Two topics are covered in this paper. In the first part the relation between
quark mass matrices and observable quantities in gauge theories. In the second
part neutrino masses and mixings in a seesaw framework.

</DOC>
<DOC>
<DOCNO> 8728 </DOCNO>
Discrete phase integral method for five-term recursion relations


  A formalism is developed to study certain five-term recursion relations by
discrete phase integral (or Wentzel-Kramers-Brillouin) methods. Such recursion
relations arise naturally in the study of the Schrodinger equation for certain
spin Hamiltonians. The conditions for the validity of the phase integral
approximation are derived. It is shown that in contrast to the three-term
problem, it is now possible to get a turning points "under the barrier", i.e.,
in the classically forbidden region, as well as inside the classically allowed
region. Further, no qualitatively new types of turning points arise in
recursion relations with still higher numbers of terms. The phase integral
approximation breaks down at the new turning points, requiring new connection
formulas, which are derived.

</DOC>
<DOC>
<DOCNO> 69625 </DOCNO>
Aharonov-Bohm and Coulomb Scattering Near the Forward Direction


  The exact wave functions that describe scattering of a charged particle by a
confined magnetic field (Aharonov-Bohm effect) and by a Coulomb field are
analyzed. It is well known that the usual procedure of finding asymptotic forms
of these functions which admit a separation into a superposition of an incident
plane wave and a circular or spherical scattered wave is problematic near the
forward direction. It thus appears to be impossible to express the conservation
of probability by means of an optical theorem of the usual kind. Both the total
cross section and the forward scattering amplitude appear to be infinite. To
address these difficulties we find a new representation for the asymptotic form
of the Aharonov-Bohm wave function that is valid for all angles. Rather than
try to define a cross section at forward angles, however, we work instead with
the probability current and find that it is quite well behaved. The same is
true for Coulomb scattering. We trace the usual difficulties to a nonuniformity
of limits.

</DOC>
<DOC>
<DOCNO> 99319 </DOCNO>
Normal Ordering for Deformed Boson Operators and Operator-valued


  The normal ordering formulae for powers of the boson number operator
$\hat{n}$ are extended to deformed bosons. It is found that for the `M-type'
deformed bosons, which satisfy $a a^{\dagger} - q a^{\dagger} a = 1$, the
extension involves a set of deformed Stirling numbers which replace the
Stirling numbers occurring in the conventional case. On the other hand, the
deformed Stirling numbers which have to be introduced in the case of the
`P-type' deformed bosons, which satisfy $a a^{\dagger} - q a^{\dagger} a =
q^{-\hat{n}}$, are found to depend on the operator $\hat{n}$. This distinction
between the two types of deformed bosons is in harmony with earlier
observations made in the context of a study of the extended
Campbell-Baker-Hausdorff formula.

</DOC>
<DOC>
<DOCNO> 40497 </DOCNO>
Heavy Quark Phenomenology from Lattice QCD


  Recent results relevant for the B-physics phenomenology, obtained from
lattice QCD simulations by the APE Collaboration, are reviewed. This includes
the B0-B0bar mixing amplitude, B-> pi semileptonic decay and the relative width
difference of B0_s mesons, $(\Delta \Gamma/\Gamma)_{B_s}$.

</DOC>
<DOC>
<DOCNO> 118031 </DOCNO>
Properties of Radio-Selected Broad Absorption-Line Quasars from the


  In a spectroscopic follow-up to the VLA FIRST survey, the FIRST Bright Quasar
Survey (FBQS) has found 29 radio-selected broad absorption line (BAL) quasars.
This sample provides the first opportunity to study the properties of
radio-selected BAL quasars. Contrary to most previous studies, we establish
that a significant population of radio-loud BAL quasars exists. Radio-selected
BAL quasars display compact radio morphologies and possess both steep and flat
radio spectra. Quasars with low-ionization BALs have a color distribution
redder than that of the FBQS sample as a whole. The frequency of BAL quasars in
the FBQS is significantly greater, perhaps by as much as a factor of two, than
that inferred from optically selected samples. The frequency of BAL quasars
appears to have a complex dependence on radio-loudness. The properties of this
sample appear inconsistent with simple unified models in which BAL quasars
constitute a subset of quasars seen edge-on.

</DOC>
<DOC>
<DOCNO> 12924 </DOCNO>
Pseudogap Induced Antiferromagnetic Spin Correlation in High-Temperature


  The pseudogap phenomena observed on cuprate high temperature superconductors
are investigated based on the exact diagonalization method on the finite
cluster t-J model. The results show the presence of the gap-like behavior in
the temperature dependence of various magnetic properties; the NMR relaxation
rate, the neutron scattering intensity and the static susceptibility. The
calculated spin correlation function indicates that the pseudogap behavior
arises associated with the development of the antiferromagnetic spin
correlation with decreasing the temperature. The numerical results are
presented to clarify the model parameter dependence, that covers the realistic
experimental situation. The effect of the next-nearest neighbor hopping $t'$ is
also studied.

</DOC>
<DOC>
<DOCNO> 68811 </DOCNO>
Quantum-Induced Soft Supersymmetry Breaking In Supergravity


  We calculate the one-loop quantum contributions to soft supersymmetry
breaking terms in the scalar potential in supergravity theories regulated \`a
la Pauli-Villars. We find ``universal'' contributions, independent of the
regulator masses and tree level soft supersymmetry breaking, that contribute
gaugino masses and A-terms equal to the ``anomaly mediated'' contributions
found in analyses using spurion techniques, as well as a scalar mass term not
identified in those analyses. The universal terms are in general modified --
and in some cases canceled -- by model-dependent terms. Under certain
restrictions on the couplings we recover the one-loop results of previous
``anomaly mediated'' supersymmetry breaking scenarios. We emphasize the model
dependence of loop-induced soft terms in the potential, which are much more
sensitive to the details of Planck scale physics then are the one-loop
contributions to gaugino masses. We discuss the relation of our results to
previous analyses.

</DOC>
<DOC>
<DOCNO> 150486 </DOCNO>
Multifractality of time and space, covariant derivatives and gauge


  A possibility to represent the standard model of fundamental particles
covariant derivatives by means of approximate generalized fractional
Riemann-Liouville derivatives of multifractal time and space model is shown.

</DOC>
<DOC>
<DOCNO> 118156 </DOCNO>
On energy spectra of UHE cosmic rays accelerated in supergalactic


  Some ultra-high energy (UHE) cosmic ray (CR) events may be correlated with
the Local Supercluster plane. We consider acceleration of such particles at the
large-scale accretion flows of matter towards such plane and/or accretion flows
onto galaxy clusters. The formed shocks and the general compression flow are
expected to allow for CR diffusive acceleration of UHE particles. For a
simplified flow geometry we consider a stationary acceleration of such CRs and
we discuss influence of model parameters on a particle spectral index. We show
that the general convergent flow pattern leads naturally to very flat proton
spectra with the phase-space spectral indices $\sigma \approx 3.0$, as compared
to the `canonical' shock value of 4.0.

</DOC>
<DOC>
<DOCNO> 70663 </DOCNO>
Dilaton Stabilization in Effective Type I String Models


  We show that the dilaton and T-moduli can be stabilized by a single gaugino
condensation mechanism in the four-dimensional effective field theory derived
from Type IIB orientifolds. A crucial role is played by the mixing of the
blowing-up modes Mk with the T-moduli in the Kahler metric, and by the presence
of the Mk in the gauge kinetic functions. Supersymmetry breaking in these
models is dominated by the auxiliary fields of the T moduli, and
phenomenologically interesting patterns can emerge.

</DOC>
<DOC>
<DOCNO> 13410 </DOCNO>
Computational Capacity of an Odorant Discriminator: the Linear


  We introduce and study an artificial neural network, inspired by the
probabilistic Receptor Affinity Distribution model of olfaction. Our system
consists on N sensory neurons whose outputs converge on a single processing
linear threshold element. The system's aim is to model discrimination of a
single target odorant from a large number p of background odorants, within a
range of odorant concentrations. We show that this is possible provided p does
not exceed a critical value p_c, and calculate the critical capacity \alpha_c =
p_c/N. The critical capacity depends on the range of concentrations in which
the discrimination is to be accomplished. If the olfactory bulb may be thought
of as a collection of such processing elements, each responsible for the
discrimination of a single odorant, our study provides a quantitative analysis
of the potential computational properties of the olfactory bulb. The
mathematical formulation of the problem we consider is one of determining the
capacity for linear separability of continuous curves, embedded in a large
dimensional space. This is accomplished here by a numerical study, using a
method that signals whether the discrimination task is realizable or not,
together with a finite size scaling analysis.

</DOC>
<DOC>
<DOCNO> 150776 </DOCNO>
Dilatonic Brane-World Black Holes, Gravity Localization and Newton


  The family of brane-world solutions of d+1-dimensional dilatonic gravity is
presented. It includes flat brane with small cosmological constant and (anti)
de Sitter brane, dilatonic brane-world black holes (Schwarzschild-(anti-) de
Sitter, Kerr, etc). Gravitational and dilatonic perturbations around such
branes are found. It is shown that near dilatonic brane-world black hole the
gravity may be localized in a standard form. The brane corrections to Newton
law are estimated. The proposal to take into account the dilaton coupled brane
matter quantum effects is made. The corresponding effective action changes the
structure of 4d de Sitter wall. RG flow of four-dimensional Newton constant in
IR and UV is briefly discussed.

</DOC>
<DOC>
<DOCNO> 12121 </DOCNO>
A new application of reduced Rayleigh equations to electromagnetic wave


  The small perturbations method has been extensively used for waves scattering
by rough surfaces. The standard method developped by Rice is difficult to apply
when we consider second and third order of scattered fields as a function of
the surface height. Calculations can be greatly simplified with the use of
reduced Rayleigh equations, because one of the unknown fields can be
eliminated. We derive a new set of four reduced equations for the scattering
amplitudes, which are applied to the cases of a rough conducting surface, and
to a slab where one of the boundary is a rough surface. As in the
one-dimensional case, numerical simulations show the appearance of enhanced
backscattering for these structures.

</DOC>
<DOC>
<DOCNO> 83167 </DOCNO>
Proceedings of the 8th International Workshop on Non-Monotonic


  The papers gathered in this collection were presented at the 8th
International Workshop on Nonmonotonic Reasoning, NMR2000. The series was
started by John McCarthy in 1978. The first international NMR workshop was held
at Mohonk Mountain House, New Paltz, New York in June, 1984, and was organized
by Ray Reiter and Bonnie Webber.
  In the last 10 years the area of nonmonotonic reasoning has seen a number of
important developments. Significant theoretical advances were made in the
understanding of general abstract principles underlying nonmonotonicity. Key
results on the expressibility and computational complexity of nonmonotonic
logics were established. The role of nonmonotonic reasoning in belief revision,
abduction, reasoning about action, planing and uncertainty was further
clarified. Several successful NMR systems were built and used in applications
such as planning, scheduling, logic programming and constraint satisfaction.
  The papers in the proceedings reflect these recent advances in the field.
They are grouped into sections corresponding to special sessions as they were
held at the workshop:
  1. General NMR track
  2. Abductive reasonig
  3. Belief revision: theory and practice
  4. Representing action and planning
  5. Systems descriptions and demonstrations
  6. Uncertainty frameworks in NMR

</DOC>
<DOC>
<DOCNO> 70494 </DOCNO>
B-Physics Phenomenology with Emphasis on the Light-Cone


  Theoretical overviews on the B-physics are presented with an emphasis on the
light-cone degrees of freedom. Our new treatment of the embedded states seems
to give an encouraging result.

</DOC>
<DOC>
<DOCNO> 169663 </DOCNO>
Upper Bound on the region of Separable States near the Maximally Mixed


  A lower bound on the amount of noise that must be added to a GHZ-like
entangled state to make it separable (also called the random robustness) is
found using the transposition condition. The bound is applicable to arbitrary
numbers of subsystems, and dimensions of Hilbert space, and is shown to be
exact for qubits. The new bound is compared to previous such bounds on this
quantity, and found to be stronger in all cases. It implies that increasing the
number of subsystems, rather than increasing their Hilbert space dimension is a
more effective way of increasing entanglement. An explicit decomposition into
an ensemble of separable states, when the state is not entangled,is given for
the case of qubits.

</DOC>
<DOC>
<DOCNO> 40050 </DOCNO>
Study of Deep Inelastic ep-Scattering at High-Q^2 with ZEUS at HERA


  Measurements of differential cross sections for deep inelastic ep
neutral-current (NC) and charged-current (CC) reactions are presented using
data taken during the 1994-97 e^+p and the 1998-99 e^-p running periods. The
structure function xF_3 has been extracted combining NC e^-p and e^+p data
sets. Both the measured cross sections and xF_3 are well described by the
standard model predictions using standard PDF's.

</DOC>
<DOC>
<DOCNO> 174505 </DOCNO>
Lambda Production and Flow in Au+Au Collisions at 11.5A GeV/c


  New data on Lambda production in Au+Au collisions at 11.5 A GeV/c are
presented. The measurements cover the rapidity range from y=2.0 to 3.5 and
transverse momenta from pt=0.15 GeV/c to 1.5 GeV/c. The rapidity distributions,
transverse momentum spectra, and azimuthal distributions are presented for
different centralities of the collision. A strong positive directed flow at
forward rapidity is observed for semicentral collisions. The measured spectra,
yields and directed flow are compared with the predictions of RQMD v2.3 model.

</DOC>
<DOC>
<DOCNO> 40428 </DOCNO>
The Electronics and Data Acquisition Systems of a CsI(Tl) Scintillating


  A 500 kg CsI(Tl) scintillating crystal detector is under construction for the
studies of low-energy neutrino physics. The requirements, design, realization
and the performance of the associated electronics, trigger, data acquisition
and software control systems are described. Possibilities for future extensions
are discussed.

</DOC>
<DOC>
<DOCNO> 121026 </DOCNO>
Strangeness in Neutron Stars


  It is generally agreed on that the tremendous densities reached in the
centers of neutron stars provide a high-pressure environment in which numerous
novel particles processes are likely to compete with each other. These
processes range from the generation of hyperons to quark deconfinement to the
formation of kaon condensates and H-matter. There are theoretical suggestions
of even more exotic processes inside neutron stars, such as the formation of
absolutely stable strange quark matter, a configuration of matter even more
stable than the most stable atomic nucleus, iron. In the latter event, neutron
stars would be largely composed of pure quark matter, eventually enveloped in a
thin nuclear crust. No matter which physical processes are actually realized
inside neutron stars, each one leads to fingerprints, some more pronounced than
others though, in the observable stellar quantities. This feature combined with
the unprecedented progress in observational astronomy, which allows us to see
vistas with remarkable clarity that previously were only imagined, renders
neutron stars to nearly ideal probes for a wide range of physical studies,
including the role of strangeness in dense matter.

</DOC>
<DOC>
<DOCNO> 8712 </DOCNO>
Composite fermions close to the one-half filling of the lowest Landau


  By strictly adhering to the microscopic theory of composite fermions (CFs)
for the Landau-level filling fractions \nu_e = p/(2 p + 1), we reproduce, with
remarkable accuracy, the surface-acoustic-wave (SAW)-based experimental results
by Willett and co-workers concerning two-dimensional electron systems with
\nu_e close to 1/2. Our results imply that the electron band mass m_b, as
distinct from the CF mass m_*, must undergo a substantial increase under the
conditions corresponding to \nu_e close to 1/2. We further establish that a
finite mean-free path \ell_0 is essential for the observed linearity of the
longitudinal conductivity \sigma_{xx}(q) as deduced from the SAW velocity
shifts.

</DOC>
<DOC>
<DOCNO> 71859 </DOCNO>
The Effect of Weak Interactions on the Ultra-Relativistic Bose-Einstein


  We calculate the ultra-relativistic Bose-Einstein condensation temperature of
a complex scalar field with weak lambda Phi^4 interaction. We show that at high
temperature and finite density we can use dimensional reduction to produce an
effective three-dimensional theory which then requires non-perturbative
analysis. For simplicity and ease of implementation we illustrate this process
with the linear delta expansion.

</DOC>
<DOC>
<DOCNO> 170782 </DOCNO>
Interferometric Tests of Teleportation


  We investigate a direct test of teleportation efficacy based on a
Mach-Zehnder interferometer. The analysis is performed for continuous variable
teleportation of both discrete and continuous observables.

</DOC>
<DOC>
<DOCNO> 69011 </DOCNO>
Back Reaction of Cosmological Perturbations


  The presence of cosmological perturbations affects the background metric and
matter configuration in which the perturbations propagate. This effect, studied
a long time ago for gravitational waves, also is operational for scalar
gravitational fluctuations, inhomogeneities which are believed to be more
important in inflationary cosmology. The back-reaction of fluctuations can be
described by an effective energy-momentum tensor. The issue of coordinate
invariance makes the analysis more complicated for scalar fluctuations than for
gravitational waves. We show that the back-reaction of fluctuations can be
described in a diffeomorphism-invariant way. In an inflationary cosmology, the
back-reaction is dominated by infrared modes. We show that these modes give a
contribution to the effective energy-momentum tensor of the form of a negative
cosmological constant whose absolute value grows in time. We speculate that
this may lead to a self-regulating dynamical relaxation mechanism for the
cosmological constant. This scenario would naturally lead to a finite remnant
cosmological constant with a magnitude corresponding to $\Omega_{\Lambda} \sim
1$.

</DOC>
<DOC>
<DOCNO> 10554 </DOCNO>
Unambiguous determination of the g-factor for holes in bismuth at high


  Magnetotransport has been investigated in high purity bismuth crystals in
static magnetic fields as high as 20 T and temperatures as low as 25 mK. This
high B/T ratio permits observation of pronounced Shubnikov-de Haas oscillations
over a wide field range and up to fields where most of the carriers are in the
lowest Landau level. For transport currents in the bisectrix or binary
directions and field in the perpendicular trigonal direction, we have observed
doublet splittings centered on each Shubnikov-de Haas oscillation. These
splittings exhibit a quadratic dependence on field and disappear before the
last oscillation. Our observations allow us to conclude unambiguously that
already when the Landau level index is as high as 2 the carriers are fully
polarized and that the g-factor for holes with the field in the trigonal
direction is 35.3(4).

</DOC>
<DOC>
<DOCNO> 68601 </DOCNO>
Anomalous t-dependence in diffractive electroproduction of 2S radially


  Within the color dipole gBFKL dynamics applied to the diffraction slope we
predict an anomalous t dependence of the differential cross section as a
function of energy and Q^2 for production of radially excited V'(2S) light
vector mesons in contradiction with a well known standard monotonous t-
behaviour for V(1S) mesons. The origin of this phenomenon is based on the
interplay of the nodal structure of V'(2S) radial wave function with the energy
and dipole size dependence of the color dipole cross section and of the
diffraction slope. We present how a different position of the node in V'(2S)
wave function leads to a different form of anomalous t- behaviour of the
differential cross section and discuss a possibility how to determine this
position from the low energy and HERA data.

</DOC>
<DOC>
<DOCNO> 101491 </DOCNO>
Legendrian mirrors and Legendrian isotopy


  We resolve a question of Fuchs and Tabachnikov by showing that there is a
Legendrian knot in standard contact three-space with zero Maslov number which
is not Legendrian isotopic to its mirror. The proof uses the differential
graded algebras of Chekanov.

</DOC>
<DOC>
<DOCNO> 170696 </DOCNO>
Perturbative corrections to photon coincidence spectroscopy


  Photon coincidence spectroscopy is a promising technique for probing the
nonlinear regime of cavity quantum electrodynamics in the optical domain,
however its accuracy is mitigated by two factors: higher-order photon
correlations, which contribute to an enhanced pair count rate, and
non-simultaneity of emitted photon pairs from the optical cavity. We show that
the technique of photon coincidence spectroscopy is effective in the presence
of these effects if the quantitative predictions are adjusted to include
non-simultaneity and higher-order correlations.

</DOC>
<DOC>
<DOCNO> 85160 </DOCNO>
Locally Anisotropic Structures and Nonlinear Connections in Einstein and


  We analyze local anisotropies induced by anholonomic frames and associated
nonlinear connections in general relativity and extensions to affine Poincare
and de Sitter gauge gravity and different types of Kaluza-Klein theories. We
construct some new classes of cosmological solutions of gravitational field
equations describing Friedmann-Robertson-Walker like universes with rotation
(ellongated and flattened) ellipsoidal or torus symmetry.

</DOC>
<DOC>
<DOCNO> 120741 </DOCNO>
The Spallagenic Production Rates of Lithium, Beryllium and Boron


  We calculate the production rates of Li6, Li7, Be9, B10 and B11 via
spallation of Carbon, Nitrogen and Oxygen nuclei by protons and alpha-particles
and by alpha-alpha fusion reactions. We include recent measurements of the
cross sections of alpha-alpha fusion reactions and find that the computations
yield rates of Li6 and Li7 production that are nearly a factor of two smaller
than previously calculated. We begin by using the `straight ahead'
approximation for the fragment energy and the `leaky-box' model for product
capture in the Galaxy. In addition we test the straight ahead approximation by
recalculating the production rates using an empirical description of the
fragment energy distribution and find that the results closely match. We have
also calculated the rates for various cosmic ray spectra and find that the
hardest spectra tested decrease the rates with CR CNO by approximately an order
of magnitude relative to our chosen standard. Finally we have computed the
Population I elemental ratios and the Population II scaling relations for our
standard and find that our computations predict an abundance of Lithium for a
given abundance of Beryllium that is 1/4 smaller than previously derived.

</DOC>
<DOC>
<DOCNO> 99980 </DOCNO>
The infimum, supremum and geodesic length of a braid conjugacy class


  Algorithmic solutions to the conjugacy problem in the braid groups B_n were
given by Elrifai-Morton in 1994 and by the authors in 1998. Both solutions
yield two conjugacy class invariants which are known as `inf' and `sup'. A
problem which was left unsolved in both papers was the number m of times one
must `cycle' (resp. `decycle') in order to increase inf (resp. decrease sup) or
to be sure that it is already maximal (resp. minimal) for the given conjugacy
class. Our main result is to prove that m is bounded above by n-2 in the
situation of the second algorithm and by ((n^2-n)/2)-1 in the situation of the
first. As a corollary, we show that the computation of inf and sup is
polynomial in both word length and braid index, in both algorithms. The
integers inf and sup determine (but are not determined by) the shortest
geodesic length for elements in a conjugacy class, as defined by Charney, and
so we also obtain a polynomial-time algorithm for computing this geodesic
length.

</DOC>
<DOC>
<DOCNO> 69660 </DOCNO>
Relaxing b\to s\gamma Constraints on the Supersymmetric Particle Mass


  We consider the radiative decay b \to s \gamma in a supersymmetric extension
of the standard model of particle interactions, where the $b$-quark mass is
entirely radiative in origin. This is accomplished by the presence of
nonholomorphic soft supersymmetry breaking terms in the Lagrangian. As a
result, the contributions to the b \to s \gamma amplitude from the charged
Higgs boson and the charginos/neutralinos are suppressed by 1/\tan^2\beta and
{\cal O}(\alpha/\alpha_s) respectively, allowing these particles to be lighter
than in the usual supersymmetric model. Their radiatively generated couplings
differ from the usual tree-level ones and change the collider phenomenology
drastically. We also study how this scenario may be embedded into a larger
framework, such as supersymmetric SU(5) grand unification.

</DOC>
<DOC>
<DOCNO> 117656 </DOCNO>
Stochastic Acceleration and Non-Thermal Radiation in Clusters of


  We calculate the distribution of electrons in clusters of galaxies, resulting
from thermalization processes in the presence of stochastic acceleration due to
plasma waves. We show that the electron distribution can deviate from a
Maxwell-Boltzmann distribution, due to the effect of the stochastic energy
gain, provided waves can be sustained against damping. The non-thermal tail of
electrons can generate as bremsstrahlung emission a flux of hard X-rays
compatible with the ones recently detected in some clusters of galaxies.

</DOC>
<DOC>
<DOCNO> 99628 </DOCNO>
Algebraic Investigation of the Soft Seven Sphere


  We investigate the seven sphere as a soft Lie algebra i.e. an algebra with
structure functions instead of structure constants. We calculate its structure
functions explicitly and also discuss some relevant points such as the validity
of the Jacobi identities. Furthermore, we emphasis some important features such
as the pointwise reduction, closure and some other consistency checks.

</DOC>
<DOC>
<DOCNO> 170090 </DOCNO>
On Galilean invariance and nonlinearity in electrodynamics and quantum


  Recent experimental results on slow light heighten interest in nonlinear
Maxwell theories. We obtain Galilei covariant equations for electromagnetism by
allowing special nonlinearities in the constitutive equations only, keeping
Maxwell's equations unchanged. Combining these with linear or nonlinear
Schroedinger equations, e.g. as proposed by Doebner and Goldin, yields a
Galilean quantum electrodynamics.

</DOC>
<DOC>
<DOCNO> 11599 </DOCNO>
Metal-Insulator Transition in Homogeneously Doped Germanium


  We have measured the electrical conductivity of Ge:Ga samples prepared by
neutron-transmutation doping of isotopically enriched 70Ge single crystals in
order to study the metal-insulator transition (MIT) ruling out an ambiguity due
to inhomogeneous distribution of impurities. The critical exponent for the
zero-temperature conductivity is 0.5 in zero magnetic field and 1.1 in magnetic
fields. Variable-range-hopping conduction of the insulating samples and
finite-temperature scaling analysis of the MIT induced by the external magnetic
field are also discussed.

</DOC>
<DOC>
<DOCNO> 81015 </DOCNO>
Dynamical Fermions with Fat Links


  We present and test a new method for simulating dynamical fermions with fat
links. Our construction is based on the introduction of auxiliary but dynamical
gauge fields and works with any fermionic action and can be combined with any
fermionic updating. In our simulation we use an over-relaxation step which
makes it effective. For four flavors of staggered fermions first results
indicate that flavor symmetry at a lattice spacing a~0.2 fm is restored to a
few percent. With the standard action this amount of flavor symmetry
restoration is achieved at a~0.07 fm. We estimate that the overall
computational cost is reduced by at least a factor 10.

</DOC>
<DOC>
<DOCNO> 118515 </DOCNO>
Near and mid-IR sub-arcsecond structure of the dusty symbiotic star R


  The results of a high-resolution interferometric campaign targeting the
symbiotic long-period variable (LPV) R~Aqr are reported. With both
near-infrared measurements on baselines out to 10m and mid-infrared data
extending to 32m, we have been able to measure the characteristic sizes of
regions from the photosphere of the LPV and its extended molecular atmosphere,
out to the cooler circumstellar dust shell. The near-infrared data were taken
using aperture masking interferometry on the Keck-I telescope and show R~Aqr to
be partially resolved for wavelengths out to 2.2 microns but with a marked
enlargement, possibly due to molecular opacity, at 3.1 microns. Mid-infrared
interferometric measurements were obtained with the U.C. Berkeley Infrared
Spatial Interferometer (ISI) operating at 11.15 microns from 1992 to 1999.
Although this dataset is somewhat heterogeneous with incomplete coverage of the
Fourier plane and sampling of the pulsation cycle, clear changes in the
mid-infrared brightness distribution were observed, both as a function of
position angle on the sky and as a function of pulsation phase. Spherically
symmetric radiative transfer calculations of uniform-outflow dust shell models
produce brightness distributions and spectra which partially explain the data,
however limitations to this approximation are noted. Evidence for significant
deviation from circular symmetry was found in the mid-infrared and more
tentatively at 3.08 microns in the near-infrared, however no clear detection of
binarity or of non-LPV elements in the symbiotic system is reported.

</DOC>
<DOC>
<DOCNO> 68228 </DOCNO>
Weak Scale Inflation and Unstable Domain Walls


  Cosmlogical domain walls produced during phase transition are expected to
collapse on a cosmologically safe timescale if Vilenkin's condition is
satisfied. We show that the decaying processes of these unstable domain walls
should be changed significantly if weak scale inflation takes place. The usual
condition for the safe decay of the cosmological domain wall must be changed,
depending on their scales and interactions. As a result, the energy scales and
explicit breaking terms of such walls must satisfy severe requirements. We also
make a brief comment on cosmological structure formation.

</DOC>
<DOC>
<DOCNO> 174584 </DOCNO>
Hot fragmentation of nuclei


  Today, we have a variety of reactions at hand that can be used to
multi-fragment nuclei. In many of these reactions even several sources of
fragments can be discerned and characterized.
  There is overwhelming evidence that these sources of fragments are hot. It is
already less clear whether heat by itself is sufficient to initiate the
fragment decay. What causes fragmentation, and when and how are the fragments
(pre)formed? These questions have remained as much a challenge as the
complementary class of questions to which they are related: What observations
derive their significance from the liquid-gas phase behavior of extended
nuclear matter? And, can we observe a phase transition in finite nuclei?
  Recent developments, largely coming from complex analyses of data sets
measured in 4-pi-type experiments as well as from calculations based on
advanced theoretical concepts, will be discussed.

</DOC>
<DOC>
<DOCNO> 122453 </DOCNO>
Argon and Silicon abundances in the damped Ly-alpha system I Zw 18


  We show that the difference between the Ar and Si relative abundance ratio
derived from FUSE absorption spectra and from the HII regions of I Zw 18 is a
consequence of the microturbulent analysis applied to the absorption spectra.
FUSE observations were performed with a large entrance aperture which fully
covered the galaxy. This means that the observed profiles are averaged over the
full body of I Zw 18, implying that large-scale velocity fields influence the
absorption - line profiles. Taking this into account, we show that the
absorption spectra are consistent with the same metal abundances as those
derived from the HII regions. It follows that no significant ionization
correction as suggested by Izotov and collaborators to describe metal contents
in damped Ly-alpha systems (DLA) is required to model abundances in the neutral
gas of I Zw 18 (a local DLA system). Using a mesoturbulent approach and
applying the generalized radiative transfer equation to the ArI1048 and
SiII1020 lines observed by Vidal-Madjar et al., we found that the profiles may
be reproduced with log (Ar/Si) ~= - 0.8 and N(SiII) ~= 4 10^{15} cm^{-2}.

</DOC>
<DOC>
<DOCNO> 117886 </DOCNO>
X-ray photoionized plasma diagnostics with Helium-like ions. Application


  We present He-like line ratios (resonance, intercombination and forbidden
lines) for totally and partially photoionized media. For solar plasmas, these
line ratios are already widely used for density and temperature diagnostics of
coronal (collisional) plasmas. In the case of totally and partially
photoionized plasmas, He-like line ratios allow for the determination of the
ionization processes involved in the plasma (photoionization with or without an
additional collisional ionization process), as well as the density and the
electronic temperature. With the new generation of X-ray satellites,
Chandra/AXAF, XMM and Astro-E, it will be feasible to obtain both high spectral
resolution and high sensitivity observations. Thus in the coming years, the
ratios of these three components will be measurable for a large number of
non-solar objects. In particular, these ratios could be applied to the Warm
Absorber-Emitter, commonly present in Active Galactic Nuclei (AGN). A better
understanding of the Warm Absorber connection to other regions (Broad Line
Region, Narrow Line Region) in AGN (Seyferts type-1 and type-2, low- and
high-redshift quasars...) will be an important key to obtaining strong
constraints on unified schemes.
  We have calculated He-like line ratios, for Z=6, 7, 8, 10, 12 and 14, taking
into account the upper level radiative cascades which we have computed for
radiative and dielectronic recombinations and collisional excitation. The
atomic data are tabulated over a wide range of temperatures in order to be used
for interpreting a large variety of astrophysical plasmas.

</DOC>
<DOC>
<DOCNO> 9573 </DOCNO>
Melting as a String-Mediated Phase Transition


  We present a theory of the melting of elemental solids as a
dislocation-mediated phase transition. We model dislocations near melt as
non-interacting closed strings on a lattice. In this framework we derive simple
expressions for the melting temperature and latent heat of fusion that depend
on the dislocation density at melt. We use experimental data for more than half
the elements in the Periodic Table to determine the dislocation density from
both relations. Melting temperatures yield a dislocation density of (0.61\pm
0.20) b^{-2}, in good agreement with the density obtained from latent heats,
(0.66\pm 0.11) b^{-2}, where b is the length of the smallest
perfect-dislocation Burgers vector. Melting corresponds to the situation where,
on average, half of the atoms are within a dislocation core.

</DOC>
<DOC>
<DOCNO> 170603 </DOCNO>
Aharonov-Bohm Effect in Cyclotron and Synchrotron Radiations


  We study the impact of Aharonov-Bohm solenoid on the radiation of a charged
particle moving in a constant uniform magnetic field. With this aim in view,
exact solutions of Klein-Gordon and Dirac equations are found in the
magnetic-solenoid field. Using such solutions, we calculate exactly all the
characteristics of one-photon spontaneous radiation both for spinless and
spinning particle. Considering non-relativistic and relativistic
approximations, we analyze cyclotron and synchrotron radiations in detail.
Radiation peculiarities caused by the presence of the solenoid may be
considered as a manifestation of Aharonov-Bohm effect in the radiation. In
particular, it is shown that new spectral lines appear in the radiation
spectrum. Due to angular distribution peculiarities of the radiation intensity,
these lines can in principle be isolated from basic cyclotron and synchrotron
radiation spectra

</DOC>
<DOC>
<DOCNO> 7881 </DOCNO>
CA Models for Traffic Flow: Comparison with Empirical Single-Vehicle


  Although traffic simulations with cellular-automata models give meaningful
results compared with empirical data, highway traffic requires a more detailed
description of the elementary dynamics. Based on recent empirical results we
present a modified Nagel-Schreckenberg cellular automaton model which
incorporates both a slow-to-start and an anticipation rule, which takes into
account especially brake lights. The focus in this article lies on the
comparison with empirical single-vehicle data.

</DOC>
<DOC>
<DOCNO> 39981 </DOCNO>
Lessons from CLEO and FOCUS Measurements of D0-anti-D0 Mixing Parameters


  If the true values of the D0-anti-D0 mixing parameters lie within the one
sigma ranges of recent measurements, then there is strong evidence for a large
width difference, y > 0.01, and large SU(3) breaking effects in strong phases,
\delta > pi/4. These constraints are model independent, and would become
stronger if M_{12}/Gamma_{12} << 1 in the D0-anti-D0 system. The interesting
fact that the FOCUS result cannot be explained by a large mass difference is
not trivial and depends on the small D0-anti-D0 production asymmetry in FOCUS
and the bounds on CP violating effects from CLEO. The large value of \delta
might help explain why y ~ sin^2(theta_c).

</DOC>
<DOC>
<DOCNO> 71217 </DOCNO>
Has HERA reached a new QCD regime?


  These notes are a summary of our efforts to answer the question in the title.
Our answer is in the affirmative as: (i) HERA data indicate a large value of
the gluon structure function; (ii) no contradictions with the asymptotic
predictions of high density QCD have been observed; and (iii) the numerical
estimates of our model give a natural description of the size of deviation from
the routine DGLAP explanation. We discuss the alternative approaches and
possible new experiments.

</DOC>
<DOC>
<DOCNO> 99996 </DOCNO>
Cardinal invariants b_kappa and t_kappa


  This paper studies cardinal invariants b_kappa and t_kappa, the natural
generalizations of the invariants b and t to a regular cardinal kappa.

</DOC>
<DOC>
<DOCNO> 69881 </DOCNO>
QCD Sum Rules for Heavy Flavors


  We give a short review of QCD sum rule results for B and D mesons and
Lambda_Q and Sigma_Q baryons. We focus mainly on recent developments concerning
semileptonic B->pion and D->pion transitions, pion couplings to heavy hadrons,
decay constants and estimates of the b quark mass from a baryonic sum rule, and
the extraction of the pion distribution amplitude from CLEO data.

</DOC>
<DOC>
<DOCNO> 178872 </DOCNO>
Multiplicity distributions associated to subthreshold events in


  Subthreshold events (pion production, for instance) at energies $E< m_{\pi}$
are treated as rare events. The associated multiplicity distribution $P_c (n)$
and the unconstrained distribution P(n), when there is no rare event-trigger,
are related by the model independent relation $P_c (n) = {n^2 \over
\average{n^2}} P(n)$. This relation, and in particular its improved version
inspired in clustering of nucleons, is in fair agreement with data. Moreover,
it allows to extract from the multiplicity data information on the number of
nucleons involved in meson production processes, occuring at energies below the
production threshold in free nucleon collisions.

</DOC>
<DOC>
<DOCNO> 151368 </DOCNO>
Gravity in a Box


  We consider a brane-world construction which incorporates a finite region of
flat space, ``the box,'' surrounded by a region of anti-de Sitter space. This
hybrid construction provides a framework which interpolates between the
scenario proposed by Arkani-Hamed, Dimopoulos and Dvali, and that proposed by
Randall and Sundrum. Within this composite framework, we investigate the
effects of resonant modes on four-dimensional gravity. We also show that, on a
probe brane in the anti-de Sitter region, there is enhanced production of
on-shell nonresonant modes. We compare our model to some recent attempts to
incorporate the Randall-Sundrum scenario into superstring theory.

</DOC>
<DOC>
<DOCNO> 85412 </DOCNO>
Solid and ocean tides and the detection of some gravitomagnetic effects


  The detection of some tiny gravitomagnetic effects in the field of the Earth
by means of artificial satellites is a very demanding task because of the
various other perturbing forces of gravitational and non-gravitational origin
acting upon them. Among the gravitational perturbations a relevant role is
played by the Earth solid and ocean tides. In this communication I outline
their effects on the detection of the Lense-Thirring drag of the orbits of
LAGEOS and LAGEOS II, currently analyzed, and the proposed GP-C experiment
devoted to the measurement of the clock effect.

</DOC>
<DOC>
<DOCNO> 71878 </DOCNO>
Quark-Gluon Plasma Signatures in Nucleus--Nucleus Collisions at CERN SPS


  Two signatures of the quark-gluon plasma -- strangeness `enhancement' and
$J/\psi$ `suppression' -- in nucleus--nucleus collisions at the SPS energies
are critically discussed.

</DOC>
<DOC>
<DOCNO> 152545 </DOCNO>
High-precision estimates of critical quantities by means of improved


  Three-dimensional spin models of the Ising and XY universality classes are
studied by a combination of high-temperature expansions and Monte Carlo
simulations applied to improved Hamiltonians. The critical exponents and the
critical equation of state are determined to very high precision.

</DOC>
<DOC>
<DOCNO> 117386 </DOCNO>
The Discovery of a Second Field Methane Brown Dwarf from Sloan Digital


  We report the discovery of a second field methane brown dwarf from the
commissioning data of the Sloan Digital Sky Survey (SDSS). The object, SDSS
J134646.45-003150.4 (SDSS 1346-00), was selected because of its very red color
and stellar appearance. Its spectrum between 0.8-2.5 mic is dominated by strong
absorption bands of H_2O and CH_4 and closely mimics those of Gliese 229B and
SDSS 162414.37+002915.6 (SDSS 1624+00), two other known methane brown dwarfs.
SDSS 1346-00 is approximately 1.5 mag fainter than Gliese 229B, suggesting that
it lies about 11 pc from the sun. The ratio of flux at 2.1 mic to that at 1.27
mic is larger for SDSS 1346-00 than for Gliese 229B and SDSS 1624+00, which
suggests that SDSS 1346-00 has a slightly higher effective temperature than the
others. Based on a search area of 130 sq. deg. and a detection limit of z* =
19.8, we estimate a space density of 0.05 pc^-3 for methane brown dwarfs with
T_eff ~ 1000 K in the 40 pc^3 volume of our search. This estimate is based on
small-sample statistics and should be treated with appropriate caution.

</DOC>
<DOC>
<DOCNO> 11473 </DOCNO>
Quantum computing and quantum measurement with mesoscopic Josephson


  Recent experimental demonstrations of quantum coherence of the charge and
flux states of Josephson junctions show that the quantum Josephson dynamics can
be used to develop scalable quantum logic circuits. In this work, I review the
basic concepts of Josephson tunneling and Josephson-junction qubits, and
discuss two problems of this tunneling motivated by quantum computing
applications. One is the theory of photon-assisted resonant flux tunneling in
SQUID systems used to demonstrate quantum coherence of flux. Another is the
problem of quantum measurement of charge with the SET electrometer. It is shown
that the SET electrometer at the Coulomb blockade threshold is the
quantum-limited detector with energy sensitivity reaching $\hbar/\sqrt{3}$ in
the resonant-tunneling regime.

</DOC>
<DOC>
<DOCNO> 85617 </DOCNO>
Cherenkov radiation in a gravitational wave background


  A covariant criterion for the Cherenkov radiation emission in the field of a
non-linear gravitational wave is considered in the framework of exact
integrable models of particle dynamics and electromagnetic wave propagation. It
is shown that vacuum interacting with curvature can give rise to Cherenkov
radiation. The conically shaped spatial distribution of radiation is derived
and its basic properties are discussed.

</DOC>
<DOC>
<DOCNO> 122539 </DOCNO>
Jet Induced Supernovae-Hydrodynamics and Observational Consequences


  Core collapse supernovae (SN) are the final stages of stellar evolution in
massive stars during which the central region collapses, forms a neutron star
(NS), and the outer layers are ejected. Recent explosion scenarios assumed that
the ejection is due to energy deposition by neutrinos into the envelope but
detailed models do not produce powerful explosions. There is mounting evidence
for an asphericity in the SN which is difficult to explain within this picture.
This evidence includes the observed high polarization, pulsar kicks, high
velocity iron-group and intermediate-mass elements material observed in
remnants, etc.
  The discovery of highly magnetars revived the idea that the basic mechanism
for the ejection of the envelope is related to a highly focused MHD-jet formed
at the NS. Our 3-D hydro simulations of the jet propagation through the star
confirmed that the mechanism can explain the asphericities.
  In this paper, detailed 3-D models for jet induced explosions of "classical"
core collapse supernovae are presented. We demonstrate the influence of the jet
properties and of the underlaying progenitor structure on the final density and
chemical structure. Finally, we discuss the observational consequences,
predictions and tests of this scenario.

</DOC>
<DOC>
<DOCNO> 69072 </DOCNO>
Combining QCD Matrix Elements and Parton Showers


  A new method for combining QCD matrix elements and parton showers in Monte
Carlo simulations of hadronic final states is outlined. The aim is to provide
at least a leading-order description of all hard multi-jet configurations
together with jet fragmentation to next-to-leading logarithmic accuracy, while
avoiding the most serious problems of double counting.

</DOC>
<DOC>
<DOCNO> 117926 </DOCNO>
Effect of Beam-Plasma Instabilities on Accretion Disk Flares


  We show that a certain class of flare models for variability from accretion
disk coronae are subject to beam-plasma instabilities. These instabilities can
prevent significant direct acceleration and greatly reduce the variable X-ray
emission argued to arise via inverse Compton scattering involving relativistic
electrons in beams and soft photons from the disk.

</DOC>
<DOC>
<DOCNO> 170277 </DOCNO>
Manipulation of Cold Atomic Collisions by Cavity QED Effects


  We show how the dynamics of collisions between cold atoms can be manipulated
by a modification of spontaneous emission times. This is achieved by placing
the atomic sample in a resonant optical cavity. Spontaneous emission is
enhanced by a combination of multiparticle entanglement together with a higher
density of modes of the modified vacuum field, in a situation akin to
superradiance. A specific situation is considered and we show that this effect
can be experimentally observed as a large suppression in trap-loss rates.

</DOC>
<DOC>
<DOCNO> 117903 </DOCNO>
Constraints on Cosmological Parameters from Future Galaxy Cluster


  We study the expected redshift evolution of galaxy cluster abundance between
0 < z < 3 in different cosmologies, including the effects of the cosmic
equation of state parameter w=p/rho. Using the halo mass function obtained in
recent large scale numerical simulations, we model the expected cluster yields
in a 12 deg^2 Sunyaev-Zeldovich Effect (SZE) survey and a deep 10^4 deg^2 X-ray
survey over a wide range of cosmological parameters. We quantify the
statistical differences among cosmologies using both the total number and
redshift distribution of clusters. Provided that the local cluster abundance is
known to a few percent accuracy, we find only mild degeneracies between w and
either Omega_m or h. As a result, both surveys will provide improved
constraints on Omega_m and w. The Omega_m-w degeneracy from both surveys is
complementary to those found either in studies of CMB anisotropies or of
high-redshift Supernovae (SNe). As a result, combining these surveys together
with either CMB or SNe studies can reduce the statistical uncertainty on both w
and Omega_m to levels below what could be obtained by combining only the latter
two data sets. Our results indicate a formal statistical uncertainty of about
3% (68% confidence) on both Omega_m and w when the SZE survey is combined with
either the CMB or SN data; the large number of clusters in the X-ray survey
further suppresses the degeneracy between w and both Omega_m and h. Systematics
and internal evolution of cluster structure at the present pose uncertainties
above these levels. We briefly discuss and quantify the relevant systematic
errors. By focusing on clusters with measured temperatures in the X-ray survey,
we reduce our sensitivity to systematics such as non-standard evolution of
internal cluster structure.

</DOC>
<DOC>
<DOCNO> 120919 </DOCNO>
Polarized mm And sub-mm Emission From Sgr A* At The Galactic Center


  The recent detection of significant linear polarization at mm and sub-mm
wavelengths in the spectrum of Sgr A* (if confirmed) will be a useful probe of
the conditions within several Schwarzschild radii ($r_S$) of the event horizon
at the Galactic Center. Hydrodynamic simulations of gas flowing in the vicinity
of this object suggest that the infalling gas circularizes when it approaches
within $5-25 r_S$ of the black hole. We suggest that the sub-mm ``excess'' of
emission seen in the spectrum of Sgr A* may be associated with radiation
produced within the inner Keplerian region and that the observed polarization
characteristics provide direct evidence for this phenomenon. The overall
spectrum from this region, including the high-energy component due to
bremsstrahlung and inverse Compton scattering processes, is at or below the
recent {\it Chandra} measurement, and may account for the X-ray source if it
turns out to be the actual counterpart to Sgr A*.

</DOC>
<DOC>
<DOCNO> 80966 </DOCNO>
A Visualization of the SU(2) Vacuum on the Lattice


  Configurations of pure SU(2) gauge field theory on the lattice are
transformed to Landau gauge. After Fourier transformation, large momentum
amplitudes are suppressed (filtered) by a variable amount, and the
configurations are transformed back to x-space. Spectacular peaks in electric
and magnetic field strengths are found, which share many properties with either
almost pointlike instantons in regular gauge or with extended anti-instantons
in singular gauge. The environment around those peaks are visualized with
respect to the action, to the topological charge density, to the gauge fields
and to electric and magnetic field strengths. The density of the peaks is of
order 1 / fm**4, and it scales according to the string tension under a
variation of the coupling constant. The evolution of the peaks under the amount
of Fourier filtering is visualy compared to the evolution under cooling, and
the gauge dependence of the peaks is discussed. Advantages and shortcomings of
this method are discussed, with emphasis on possible strong distortions of the
action and topological charge density, which become gauge dependent. Finally, I
compare the character of the SU(2)-configurations to those of noncompact
abelian theory.

</DOC>
<DOC>
<DOCNO> 121060 </DOCNO>
Exploring the Structure of Distant Galaxies with Adaptive Optics on the


  We report on the first observation of cosmologically distant field galaxies
with an high order Adaptive Optics (AO) system on an 8-10 meter class
telescope. Two galaxies were observed at 1.6 microns at an angular resolution
as high as 50 milliarcsec using the AO system on the Keck-II telescope. Radial
profiles of both objects are consistent with those of local spiral galaxies and
are decomposed into a classic exponential disk and a central bulge. A
star-forming cluster or companion galaxy as well as a compact core are detected
in one of the galaxies at a redshift of 0.37+/-0.05. We discuss possible
explanations for the core including a small bulge, a nuclear starburst, or an
active nucleus. The same galaxy shows a peak disk surface brightness that is
brighter than local disks of comparable size. These observations demonstrate
the power of AO to reveal details of the morphology of distant faint galaxies
and to explore galaxy evolution.

</DOC>
<DOC>
<DOCNO> 71417 </DOCNO>
Time Evolution of Fast Particles During the Decay of Hadronic Systems


  A phenomenological model is presented based on the formation of nuclear
thermodynamic system during the collision of heavy ions in the regime of
intermediate and high energy regions. The formulation and the dynamic picture
are determined by solving the Vlasov equation. The solution is dressed in the
form of a power series. The first term of which is the equilibrium distribution
in phase space. The rest, are time dependent perturbation terms due to the
multiple strong interactions inside the system. The temperature gradient and
the derivatives of the phase function are calculated. The time dependence of
the angular emission of the produced particles is studied. It is found that
particles emitted in the forward direction are produced in the early stage of
the reaction, far from the equilibrium. Backward production comes in a later
stage when the system constituents undergo multiple cascade collisions.

</DOC>
<DOC>
<DOCNO> 121962 </DOCNO>
Evidence for the Heating of Atomic Interstellar Gas by PAHs


  We report a strong correlation between the [CII] 158 micron cooling line and
the mid-infrared flux in the 5-10 micron range in a wide variety of
star-forming galaxies. The mid-infrared flux is dominated by Aromatic Feature
Emission (AFE), which is thought to arise from large polycyclic aromatic
hydrocarbon molecules or `PAHs' and generally associated with the smallest
interstellar grains. The [CII] line is the dominant gas coolant in most regions
of atomic interstellar gas, and therefore reflects the heating input to the
gas. The ratio of these two quantities, [CII]/AFE, remains nearly constant with
the ratio of the IRAS 60 micron band flux to the 100 micron band flux,
R(60/100). This is in contrast to the drop in the [CII]/FIR ratio with
increasing R(60/100), which signal higher dust temperatures and more intense
radiation fields. We interpret the stable [CII]/AFE ratio as evidence that gas
heating is dominated by the PAHs or small grains which are also AFE carriers
over a wide range of conditions. The trend of decreasing [CII]/FIR with
increasing radiation field suggests a decrease in the importance of PAHs or
small grains relative to large grains both in gas heating and in dust cooling.
We summarize the observed trends and suggest two plausible scenarios.

</DOC>
<DOC>
<DOCNO> 101430 </DOCNO>
Trace functionals on non-commutative deformations of moduli spaces of


  We describe an efficient construction of a canonical non-commutative
deformation of the algebraic functions on the moduli spaces of flat connections
on a Riemann surface. We show that this algebra, which is a variant of the
quantum moduli algebra introduced by Alekseev-Grosse-Schomerus and
Buffenoir-Roche, has a trace functional which is related to the canonical trace
in the formal index theory of Fedosov and Nest-Tsygan via the Verlinde formula.

</DOC>
<DOC>
<DOCNO> 9294 </DOCNO>
Magnetic stress as a driving force of structural distortions: the case


  We show that the observed transition from rocksalt to orthorhombic P$_{nma}$
symmetry in CrN can be understood in terms of stress anisotropy. Using local
spin density functional theory, we find that the imbalance between stress
stored in spin-paired and spin-unpaired Cr nearest neighbors causes the
rocksalt structure to be unstable against distortions and justifies the
observed antiferromagnetic ordering. This stress has a purely magnetic origin,
and may be important in any system where the coupling between spin ordering and
structure is strong.

</DOC>
<DOC>
<DOCNO> 151133 </DOCNO>
Crossing probabilities on same-spin clusters in the two-dimensional


  Probabilities of crossing on same-spin clusters, seen as order parameters,
have been introduced recently for the critical 2d Ising model by Langlands,
Lewis and Saint-Aubin. We extend Cardy's ideas, introduced for percolation, to
obtain an ordinary differential equation of order 6 for the horizontal crossing
probability pih. Due to the identity pih(r)+pih(1/r)=1, the function pih must
lie in a 3-dimensional subspace. New measurements of pih are made for 40 values
of the aspect ratio r (r in [0.1443,6.928]). These data are more precise than
those obtained by Langlands et al as the 95%-confidence interval is brought to
4x10^{-4}. A 3-parameter fit using these new data determines the solution of
the differential equation. The largest gap between this solution and the 40
data is smaller than 4x10^{-4}. The probability pihv of simultaneous horizontal
and vertical crossings is also treated.

</DOC>
<DOC>
<DOCNO> 99891 </DOCNO>
Rectangular Scott-type Permanents


  Let $x_1,x_2,...,x_n$ be the zeroes of a polynomial P(x) of degree n and
$y_1,y_2,...,y_m$ be the zeroes of another polynomial Q(y) of degree m. Our
object of study is the permanent $\per(1/(x_i-y_j))_{1\le i\le n, 1\le j\le
m}$, here named "Scott-type" permanent, the case of $P(x)=x^n-1$ and
$Q(y)=y^n+1$ having been considered by R. F. Scott. We present an efficient
approach to determining explicit evaluations of Scott-type permanents, based on
generalizations of classical theorems by Cauchy and Borchardt, and of a recent
theorem by Lascoux. This continues and extends the work initiated by the first
author ("G\'en\'eralisation de l'identit\'e de Scott sur les permanents," to
appear in Linear Algebra Appl.). Our approach enables us to provide numerous
closed form evaluations of Scott-type permanents for special choices of the
polynomials P(x) and Q(y), including generalizations of all the results from
the above mentioned paper and of Scott's permanent itself. For example, we
prove that if $P(x)=x^n-1$ and $Q(y)=y^{2n}+y^n+1$ then the corresponding
Scott-type permanent is equal to $(-1)^{n+1}n!$.

</DOC>
<DOC>
<DOCNO> 120948 </DOCNO>
The Origins of Disk Heating


  By making spectral absorption-line observations of disk galaxies at
intermediate inclinations, we have been able to determine the amplitude of
their constituent stars' random motions in three dimensions. This full measure
of the shape of the velocity ellipsoid is a useful diagnostic for determining
the "heating" mechanism responsible for creating the random motions. The
analysis implies that the main heating process varies with galaxy type, with
minor mergers dominating the heating in early-type disk galaxies, and spiral
density waves the most important mechanism in late-type systems.

</DOC>
<DOC>
<DOCNO> 10874 </DOCNO>
Coulomb Gap: How a Metal Film Becomes an Insulator


  Electron tunneling measurements of the density of states (DOS) in ultra-thin
Be films reveal that a correlation gap mediates their insulating behavior. In
films with sheet resistance $R<5000\Omega$ the correlation singularity appears
as the usual perturbative $ln(V)$ zero bias anomaly (ZBA) in the DOS. As R is
increased further, however, the ZBA grows and begins to dominate the DOS
spectrum. This evolution continues until a non-perturbative $|V|$
Efros-Shklovskii Coulomb gap spectrum finally emerges in the highest R films.
Transport measurements of films which display this gap are well described by a
universal variable range hopping law $R(T)=(h/2e^2)exp(T_o/T)^{1/2}$.

</DOC>
<DOC>
<DOCNO> 123332 </DOCNO>
Relativistic models of kHz QPOs


  After reviewing the general-relativistic ``gap'' model of accretion, I
discuss its relation to the high frequency quasi-periodic oscillations observed
in low-mass X-ray binaries. The ``300'' Hz frequency seen in some X-ray bursts
may be a relativistic signature of keplerian rotation of the neutron star.

</DOC>
<DOC>
<DOCNO> 122028 </DOCNO>
Heavy element abundances in DA white dwarfs


  We present a series of systematic abundance measurements for a group of hot
DA white dwarfs in the temperature range 20,000-75,000K, based on far-UV
spectroscopy with STIS on HST, IUE and FUSE. Using our latest heavy element
blanketed non-LTE stellar atmosphere calculations we have addressed the heavy
element abundance patterns for the hottest stars for the first time, showing
that they are similar to objects like G191-B2B. The abundances observed in the
cooler (<50,000K) white dwarfs are something of a mystery. Some of the patterns
(e.g. REJ1032) can be explained by self-consistent levitation-diffusion
calculations but there is then a serious difficulty in understanding the
appearance of the apparently pure H atmospheres. We also report the detection
of photospheric HeII in the atmosphere of WD2218+706.

</DOC>
<DOC>
<DOCNO> 7687 </DOCNO>
Josephson Effect in Magnetic Superconductors with Spiral Magnetic Order


  It is shown that in magnetic superconductors with spiral magnetic order the
Josephson current has an additional contribution which depends: (i) on the
relative orientation (magnetic phase) $\theta =\theta_{L}-\theta_{R}$ of
magnetizations on the left ($L$) and right ($R$) banks of the contact, (ii) on
the junction helicity $\chi =\chi_{L}\chi_{R}$, (with spiral helicity $\chi
_{L(R)}=\pm 1$), i.e. $J=[J_{c}-J_{\chi}\cos \theta ]\sin \phi $ with $\phi
=\phi_{L}-\phi_{R}$. The ratio $R_{\chi}\equiv J_{\chi}/J_{c}$ is calculated as
a function of the superconducting order parameter $\Delta $, the exchange field
energy $h$ and the wave vector $Q$ of the spiral magnetic structure. The $\pi
$-Josephson contact can be realized in such a system in some region of
parameters. Some possible consequences of this new phase relation is also
analyzed.

</DOC>
<DOC>
<DOCNO> 13924 </DOCNO>
Effective Interaction Hamiltonian of Polaron Pairs in Diluted Magnetic


  The magnetic interaction of a pair of bound magnetic polarons (BMP) in
diluted magnetic semiconductors (DMS) is analyzed via a generalized
Hubbard-type Hamiltonian for two carriers in the presence of effective magnetic
fields arising from the magnetic polarization of their respective polarons. For
the case where the magnetic fields at the two sites have equal magnitude but
are allowed to have arbitrary directions, it is shown that the energy of the
two polarons is minimized for a ferromagnetic configuration of the carrier
spins (in contrast to the case of hydrogenic centers in nonmagnetic
semiconductors) if polaron fields are strong enough. A modified Heisenberg-type
Hamiltonian is constructed to describe the low energy states of the resulting
system.

</DOC>
<DOC>
<DOCNO> 68880 </DOCNO>
B_c Meson Production in Nuclear Collisions at RHIC


  We study quantitatively the formation and evolution of B_c bound states in a
space-time domain of deconfined quarks and gluons (quark-gluon plasma, QGP). At
the Relativistic Heavy Ion Collider (RHIC) one expects for the first time that
typical central collisions will result in multiple pairs of heavy (in this case
charmed) quarks. This provides a new mechanism for the formation of heavy
quarkonia which depends on the properties of the deconfined region. We find
typical enhancements of about 500 fold for the B_c production yields over
expectations from the elementary coherent hadronic B_c-meson production
scenario. The final population of bound states may serve as a probe of the
plasma phase parameters.

</DOC>
<DOC>
<DOCNO> 100601 </DOCNO>
Euler characteristics of universal cotangent line bundles on $\ms_{1,n}$


  A scheme of computing $\chi(\ms_{1,n}, L_1^{\otimes d_1}\otimes ... \otimes
L_n^{\otimes d_n})$ is given. Here $\ms_{1,n}$ is the moduli space of
$n$-pointed stable curves of genus one and $L_i$ are the universal cotangent
line bundles. This is a sequel of our previous work in IMRN. The entire program
is to carry out a $K$-theoretic version of Kontsevich--Witten theory on
two-dimensional gravity.

</DOC>
<DOC>
<DOCNO> 121383 </DOCNO>
On the stability of very massive primordial stars


  The stability of metal-free very massive stars ($Z$ = 0; $M = 120 - 500
\msol$) is analyzed and compared with metal-enriched stars. Such zero-metal
stars are unstable to nuclear-powered radial pulsations on the main sequence,
but the growth time scale for these instabilities is much longer than for their
metal-rich counterparts. Since they stabilize quickly after evolving off the
ZAMS, the pulsation may not have sufficient time to drive appreciable mass loss
in Z = 0 stars. For reasonable assumptions regarding the efficiency of
converting pulsational energy into mass loss, we find that, even for the larger
masses considered, the star may die without losing a large fraction of its
mass. We find a transition between the $\epsilon$- and $\kappa$-mechanisms for
pulsational instability at $Z\sim 2\E{-4} - 2\E{-3}$. For the most metal-rich
stars, the $\kappa$-mechanism yields much shorter $e$-folding times, indicating
the presence of a strong instability. We thus stress the fundamental difference
of the stability and late stages of evolution between very massive stars born
in the early universe and those that might be born today.

</DOC>
<DOC>
<DOCNO> 121726 </DOCNO>
Molecular Gas and the Modest Star Formation Efficiency in the


  (abridged) We report here a factor of 5.7 higher total CO flux in Arp~244
(the ``Antennae'' galaxies) than that previously accepted in the literature
(thus a total molecular gas mass of 1.5x10$^{10}$ Msun), based on our fully
sampled CO(1-0) observations at the NRAO 12m telescope. Our observations show
that the molecular gas peaks predominately in the disk-disk overlap region
between the nuclei, similar to the far-infrared (FIR) and mid-infrared (MIR)
emission. The bulk of the molecular gas is forming into stars with a normal
star formation efficiency (SFE) L_{IR}/M(H_2) \approx 4.2 Lsun/Msun, same as
that of giant molecular clouds in the Galactic disk. Additional supportive
evidence is the extremely low fraction of the dense molecular gas in Arp~244,
revealed by our detections of the HCN(1-0) emission.
  We estimate the local SFE indicated by the ratio map of the radio continuum
to CO(1-0) emission. Remarkably, the local SFE stays roughly same over the bulk
of the molecular gas distribution. Only some localized regions show the highest
radio-to-CO ratios that we have identified as the sites of the most intense
starbursts with SFE >~ 20 Lsun/Msun. These starburst regions are confined
exclusively in the dusty patches seen in the HST images near the CO and FIR
peaks where presumably the violent starbursts are heavily obscured.
Nevertheless, recent large-scale star formation is going on throughout the
system, yet the measured level is more suggestive of a moderate starburst (SFE
>~ 10 Lsun/Msun) or a weak to normal star formation (SFE ~ 4 Lsun/Msun). The
overall starburst from the bulk of the molecular gas is yet to be initiated as
most of the gas further condenses into kpc scale in the final coalescence.

</DOC>
<DOC>
<DOCNO> 117128 </DOCNO>
A two wire waveguide and interferometer for cold atoms


  A versatile miniature de Broglie waveguide is formed by two parallel
current-carrying wires in the presence of a uniform bias field. We derive a
variety of analytical expressions to describe the guide and present a quantum
theory to show that it offers a remarkable range of possibilities for atom
manipulation on the sub-micron scale. These include controlled and coherent
splitting of the wavefunction as well as cooling, trapping and guiding. In
particular we discuss a novel microscopic atom interferometer with the
potential to be exceedingly sensitive.

</DOC>
<DOC>
<DOCNO> 170708 </DOCNO>
Phase Conjugation of Continuous Quantum Variables


  The phase conjugation of an unknown Gaussian state cannot be realized
perfectly by any physical process. A semi-classical argument is used to derive
a tight lower bound on the noise that must be introduced by an approximate
phase conjugation operation. A universal transformation achieving the optimal
imperfect phase conjugation is then presented, which is the continuous
counterpart of the universal-NOT transformation for quantum bits. As a
consequence, it is also shown that more information can be encoded into a pair
of conjugate Gaussian states than using twice the same state.

</DOC>
<DOC>
<DOCNO> 13227 </DOCNO>
Crossover from thermal to quantum creep in layered antiferromagnetic


  The influence of the antiferromagnetic order on the superconductor in the
mixed state results in creation of spin-flop domains along the cores of the
vortex lines. It is shown that this phenomenon makes possible crossover from
quantum creep regime to thermal one, and vice versa, at constant temperature.
To do this one needs to simply change the intensity or the direction of applied
magnetic field in the basal ${\bf ab}$ plane of layered structure.

</DOC>
<DOC>
<DOCNO> 116320 </DOCNO>
Density Functional Study of adsorption of molecular hydrogen on graphene


  Density functional theory has been used to study the adsorption of molecular
H2 on a graphene layer. Different adsorption sites on top of atoms, bonds and
the center of carbon hexagons have been considered and compared. We conclude
that the most stable configuration of H2 is physisorbed above the center of an
hexagon. Barriers for classical diffusion are, however, very small.

</DOC>
<DOC>
<DOCNO> 84523 </DOCNO>
Post-Newtonian Gravitational Radiation


  1 Introduction 2 Multipole Decomposition 3 Source Multipole Moments 4
Post-Minkowskian Approximation 5 Radiative Multipole Moments 6 Post-Newtonian
Approximation 7 Point-Particles 8 Conclusion

</DOC>
<DOC>
<DOCNO> 121087 </DOCNO>
N-Body Simulations of Compact Young Clusters near the Galactic Center


  We investigate the dynamical evolution of compact young star clusters (CYCs)
near the Galactic center (GC) using Aarseth's Nbody6 codes. The relatively
small number of stars in the cluster (5,000-20,000) makes real-number N-body
simulations for these clusters feasible on current workstations. Using
Fokker-Planck (F-P) models, Kim, Morris, & Lee (1999) have made a survey of
cluster lifetimes for various initial conditions, and have found that clusters
with a mass <~ 2x10^4 Msun evaporate in ~10 Myr. These results were, however,
to be confirmed by N-body simulations because some extreme cluster conditions,
such as strong tidal forces and a large stellar mass range participating in the
dynamical evolution, might violate assumptions made in F-P models. Here we find
that, in most cases, the CYC lifetimes of previous F-P calculations are 5-30%
shorter than those from the present N-body simulations. The comparison of
projected number density profiles and stellar mass functions between N-body
simulations and HST/NICMOS observations by Figer et al. (1999) suggests that
the current tidal radius of the Arches cluster is ~1.0 pc, and the following
parameters for the initial conditions of that cluster: total mass of 2x10^4
Msun and mass function slope for intermediate-to-massive stars of 1.75 (the
Salpeter function has 2.35). We also find that the lower stellar mass limit,
the presence of primordial binaries, the amount of initial mass segregation,
and the choice of initial density profile (King or Plummer models) do not
significantly affect the dynamical evolution of CYCs.

</DOC>
<DOC>
<DOCNO> 102624 </DOCNO>
On irreducibility of tensor products of Yangian modules associated with


  We study the tensor product $W$ of any number of "elementary" irreducible
modules $V_1,...,V_k$ over the Yangian of the general linear Lie algebra. Each
of these modules is determined by a skew Young diagram and a complex parameter.
For any indices $i,j=1,...,k$ there is a canonical non-zero intertwining
operator $A_{ij}$ between the tensor products $V_i\otimes V_j$ and $V_j\otimes
V_i$. This operator is defined up to a scalar multipler. We show that the
tensor product $W$ is irreducible, if and only if all operators $A_{ij}$ with
$i<j$ are invertible. This implies that the Yangian module $W$ is irreducible,
if and only if all pairwise tensor products $V_i\otimes V_j$ with $i<j$ are
irreducible. We also introduce the notion of a Durfee rank of a skew Young
diagram. For an ordinary Young diagram, this is the length of its main
diagonal.

</DOC>
<DOC>
<DOCNO> 71868 </DOCNO>
Vanishing of cosmological constant in nonfactorizable geometry


  We generalize the results of Randall and Sundrum to a wider class of
four-dimensional space-times including the four-dimensional Schwarzschild
background and de Sitter universe. We solve the equation for graviton
propagation in a general four dimensional background and find an explicit
solution for a zero mass bound state of the graviton. We find that this zero
mass bound state is normalizable only if the cosmological constant is strictly
zero, thereby providing a dynamical reason for the vanishing of cosmological
constant within the context of this model. We also show that the results of
Randall and Sundrum can be generalized without any modification to the
Schwarzschild background.

</DOC>
<DOC>
<DOCNO> 72307 </DOCNO>
Deconfining Phase Transition in QCD_4 and QED_4 at Finite Temperature


  We investigate the deconfining phase transition in QCD_4 and QED_4 at finite
temperature using a perturbative deformation of topological quantum field
theory (TQFT). A modified maximal abelian gauge (MAG) is utilized in the
analysis. In this case, we can derive the linear potential studying the 2D
theory through Parisi-Sourlas (PS) dimensional reduction. The mechanism of
deconfining phase transition is proposed. It is geometrical to discuss the
thermal effect on the linear potential. All we have to do is to investigate the
behavior of topological objects as such instantons and vortices on a cylinder.
This is the great advantage of our scenario. This mechanism is also applied in
the case of QED_4. The phase structure at the high temperature of QED is
investigated using the Coulomb potential on a cylinder. It coincides with the
result in the lattice compact U(1) gauge theory. Also, QCD with MAG has the
property called the abelian dominance, which enables us to discuss the
deconfinement of QCD_4.

</DOC>
<DOC>
<DOCNO> 118624 </DOCNO>
Measuring the galaxy power spectrum and scale-scale correlations with


  We present a method of measuring galaxy power spectrum based on the
multiresolution analysis of the discrete wavelet transformation (DWT). Since
the DWT representation has strong capability of suppressing the off-diagonal
components of the covariance for selfsimilar clustering, the DWT covariance for
popular models of the cold dark matter cosmogony generally is diagonal, or
$j$(scale)-diagonal in the scale range, in which the second scale-scale
correlations are weak. In this range, the DWT covariance gives a lossless
estimation of the power spectrum, which is equal to the corresponding Fourier
power spectrum banded with a logarithmical scaling. In the scale range, in
which the scale-scale correlation is significant, the accuracy of a power
spectrum detection depends on the scale-scale or band-band correlations. This
is, for a precision measurements of the power spectrum, a measurement of the
scale-scale or band-band correlations is needed. We show that the DWT
covariance can be employed to measuring both the band-power spectrum and second
order scale-scale correlation. We also present the DWT algorithm of the binning
and Poisson sampling with real observational data. We show that the alias
effect appeared in usual binning schemes can exactly be eliminated by the DWT
binning. Since Poisson process possesses diagonal covariance in the DWT
representation, the Poisson sampling and selection effects on the power
spectrum and second order scale-scale correlation detection are suppressed into
minimum. Moreover, the effect of the non-Gaussian features of the Poisson
sampling can be calculated in this frame.

</DOC>
<DOC>
<DOCNO> 8040 </DOCNO>
Vortex lattice structures and pairing symmetry in Sr2RuO4


  Recent experimental results indicate that superconductivity in Sr2RuO4 is
described by the p-wave E_u representation of the D_{4h} point group. Results
on the vortex lattice structures for this representation are presented. The
theoretical results are compared with experiment.

</DOC>
<DOC>
<DOCNO> 40461 </DOCNO>
Lectures on Technicolor and Compositeness


  Lecture 1 provides an introduction to dynamical electroweak symmetry
breaking. Lectures 2 and 3 give an introduction to compositeness, with emphasis
on effective lagrangians, power-counting, and the 't Hooft anomaly-matching
conditions.

</DOC>
<DOC>
<DOCNO> 80742 </DOCNO>
Renormalisation and off-shell improvement in lattice perturbation theory


  We discuss the improvement of flavour non-singlet point and one-link lattice
quark operators, which describe the quark currents and the first moment of the
DIS structure functions respectively. Suitable bases of improved operators are
given, and the corresponding renormalisation factors and improvement
coefficients are calculated in one-loop lattice perturbation theory, using the
Sheikholeslami-Wohlert (clover) action. To this order we achieve off-shell
improvement by eliminating the effect of contact terms. We use massive
fermions, and our calculations are done keeping all terms up to first order in
the lattice spacing, for arbitrary m^2/p^2, in a general covariant gauge. We
also compare clover fermions with fermions satisfying the Ginsparg-Wilson
relation, and show how to remove O(a) effects off-shell in this case too, and
how this is in many aspects simpler than for clover fermions. Finally, tadpole
improvement is also considered.

</DOC>
<DOC>
<DOCNO> 151216 </DOCNO>
Shadow multiplets in AdS_4/CFT_3 and the super-Higgs mechanism: hints of


  We discuss a general pairing that occurs in compactifications of M-theory on
AdS_4 x X^7 backgrounds between massless ultra short multiplets and their
massive shadows, namely certain universal long multiplets with fixed protected
dimensions. In particular we consider the shadow of the short graviton
multiplet in N=3 compactifications. It turns out to be a massive spin 3/2
multiplet with scale dimension E_0=3 and with the quantum numbers of a
super-Higgs multiplet. Hence each N=3 AdS_4 x X^7 vacuum is actually to be
interpreted as a spontaneously broken phase of an N=4 theory. Comparison with
standard gauged N=4 supergravity in 4 dimensions reveals the unexpected bound
E_0<3 on the dimension of the broken gravitino multiplet. This hints to the
existence of new versions of extended supergravities, in particular N=4 where
such upper bounds are evaded and where all possible vacua have a reduced
supersymmetry N_0<N. We name them shadow supergravities. In particular, using
arguments based on the solvable Lie algebra parametrization of the scalar
manifold, we discuss the possible structure of shadow N=4 supergravity. Using
our previous results on the SCFT dual of the AdS_4 x N^{0,1,0} vacuum we
discuss the SCFT realization of the universal N=3 shadow multiplet. RG flows
from an N=4 to an N=3 phase are ruled out by the fact that the N=4 vacuum is at
infinite distance in moduli space, denoting the presence of a topology change.

</DOC>
<DOC>
<DOCNO> 10062 </DOCNO>
Influence of Quasi-Bi-Stripe Charge Order on the Resistivity and


  The charge ordering in the bilayer manganite system
La$_{2-2x}$Sr$_{1+2x}$Mn$_{2}$O$_{7}$ with $0.30 \le x \le 0.50$ has been
studied by neutron diffraction. The charge order is characterized by the
propagation vector parallel to the [1 0 0] direction (MnO$_2$ direction), but
the correlation length is short-ranged and extremely anisotropic, being $\sim
0.02a^{*}$ and $\sim 0.2a^{*}$ parallel and perpendicular to the modulation
direction, respectively. The observed charge order can be viewed as a
quasi-bi-stripe order, and accounts well for the $x$ dependence of the
resistivity. The quasi-bistripe order is stable within the ferromagnetic (FM)
MnO$_2$ layers in the A-type antiferromagnetic order, but is instabilized by
the 3 dimensional FM order.

</DOC>
<DOC>
<DOCNO> 118345 </DOCNO>
Jupiter's hydrocarbons observed with ISO-SWS: vertical profiles of C2H6


  We have analysed the ISO-SWS spectrum of Jupiter in the 12-16 micron range,
where several hydrocarbons exhibit rovibrational bands. Using temperature
information from the methane and hydrogen emissions, we derive the mixing
ratios (q) of acetylene and ethane at two independent pressure levels. For
acetylene, we find $q=(8.9^{+1.1}_{-0.6})\times10^{-7}$ at 0.3 mbar and
$q=(1.1^{+0.2}_{-0.1})\times10^{-7}$ at 4 mbar, giving a slope $-d\ln q / d\ln
P=0.8\pm0.1$, while for ethane $q=(1.0\pm0.2)\times10^{-5}$ at 1 mbar and
$q=(2.6^{+0.5}_{-0.6})\times10^{-6}$ at 10 mbar, giving $-d\ln q / d\ln
P=0.6\pm0.2$. The ethane slope is consistent with the predictions of Gladstone
et al. (1996), but that predicted for acetylene is larger than we observe. This
disagreement is best explained by an overestimation of the acetylene production
rate compared to that of ethane in the Gladstone et al. (1996) model.
  At 15.8 micron, methylacetylene is detected for the first time at low jovian
latitudes, and a stratospheric column density of $(1.5\pm0.4)\times10^{15}$
molecule.cm-2 is inferred. We also derive an upper limit for the diacetylene
column density of $7\times10^{13}$ molecule.cm-2.

</DOC>
<DOC>
<DOCNO> 85565 </DOCNO>
Relativity in space-times with short-distance structure governed by an


  I show that it is possible to formulate the Relativity postulates in a way
that does not lead to inconsistencies in the case of space-times whose
short-distance structure is governed by an observer-independent length scale.
The consistency of these postulates proves incorrect the expectation that
modifications of the rules of kinematics involving the Planck length would
necessarily require the introduction of a preferred class of inertial
observers. In particular, it is possible for every inertial observer to agree
on physical laws supporting deformed dispersion relations of the type $E^2- c^2
p^2- c^4 m^2 + f(E,p,m;L_p)=0$, at least for certain types of $f$.

</DOC>
<DOC>
<DOCNO> 102727 </DOCNO>
The Vlasov-Poisson system with radiation damping


  We set up and analyze a model of radiation damping within the framework of
continuum mechanics, inspired by a model of post-Newtonian hydrodynamics due to
Blanchet, Damour and Schaefer. In order to simplify the problem as much as
possible we replace the gravitational field by the electromagnetic field and
the fluid by kinetic theory. We prove that the resulting system has a
well-posed Cauchy problem globally in time for general initial data and in all
solutions the fields decay to zero at late times. In particular, this means
that the model is free from the runaway solutions which frequently occur in
descriptions of radiation reaction.

</DOC>
<DOC>
<DOCNO> 69486 </DOCNO>
Generic Relations of Flavor Mixings between Leptons and Quarks in SU(5)


  We have studied implications of the generic lopsided mass matrix of the
charged leptons by taking the SU(5) GUT relation in the nearest-neighbor
interaction (NNI) basis. We have found four interesting relations among the
lepton mixings and the quark ones, which are independent of details of the
model. These relations are discussed by using the experimental data. We have
also discussed the relation between U_{e2} and U_{e3} incuding the contribution
from the neutrino mass matrix. We have presented the probable value U_{e3}=0.05
\sim 0.16, which is independent of the solar neutrino solutions. The CP
violating quantity J_{CP} is also discussed.

</DOC>
<DOC>
<DOCNO> 122793 </DOCNO>
VLA HI Line Observations of the Extremely Metal-Poor Blue Compact Dwarf


  We present the results of HI mapping with the NRAO VLA of one of the most
metal-deficient blue compact dwarf (BCD) galaxies known, SBS 0335-052, with an
oxygen abundance of only 1/40 that of the Sun. We study the structure and
dynamics of the neutral gas in this chemically young object with a spatial
resolution of 20.5"x15" (~ 5.4 x 3.9 kpc at an assumed distance of 54.3 Mpc), a
sensitivity at the 2sigma detection level of ~2.0K or 7.5x10^19 cm^-2 and a
velocity resolution of 21.2 km s^-1. We detected a large HI complex associated
with this object with an overall size of about 66 by 22 kpc and elongated in
the East-West direction. There are two prominent, slightly resolved peaks
visible in the integrated HI map, separated in the East-West direction by 22
kpc (84"). The eastern peak is nearly coincident with the position of the
optical galaxy SBS 0335-052. The western peak is about a factor of 1.3 brighter
in the HI line and is identified with a faint blue compact dwarf galaxy, SBS
0335-052W, with m_B = 19.4, and a metallicity close to the lowest values known
for BCDs, about 1/50 that of the Sun. The radial velocities of both systems are
similar, suggesting that the two BCDs SBS 0335-052 and SBS 0335-052W constitute
a pair of dwarf galaxies embedded in a common HI envelope. Alternatively, the
BCDs can be the nuclei of two distinct interacting primordial HI clouds. The
estimated total dynamical mass, assuming the BCDs form a bound system, is
larger than 6x10^9 Msun. This is to be compared to a total gaseous mass M_gas =
2.1x10^9 Msun, and a total stellar mass Mstar < 10^8 Msun. Hence, the mass of
the SBS 0335-052 system is dominated by dark matter (abridged).

</DOC>
<DOC>
<DOCNO> 152398 </DOCNO>
Brane Cosmology with Non-Static Bulk


  We study the brane world motion in non-static bulk by generalizing the second
Randall-Sundrum scenario Explicitly, we take the bulk to be a Vaidya-AdS
metric, which describes the gravitational collapse of a spherically symmetric
null dust fluid in Anti-de Sitter spacetime. We point out that during an
inflationary phase on the brane, black holes will tend to be thermally
nucleated in the bulk We analyze the thermodynamical properties of this
brane-world.We point out that during an inflationary phase on the brane, black
holes will tend to be thermally nucleated in the bulk. Thermal equilibrium of
the system is discussed. We calculate the late time behavior of this system,
including 1-loop effects. We argue that at late times a sufficiently large
black hole will relax to a point of thermal equilibrium with the brane-world
environment. This result has interesting implications for early-universe
cosmology.

</DOC>
<DOC>
<DOCNO> 101224 </DOCNO>
Curvature and symmetry of Milnor spheres


  In this paper we explore the geometry and topology of cohomogeneity one
manifolds, i.e. manifolds with a group action whose principal orbits are
hypersurfaces. We show that the principal group action of every principal
SO(3) and SO(4) bundle over S^4 extends to a cohomogeneity one action. As a
consequence we prove that every vector bundle and every sphere bundle over S^4
has a complete metric with non-negative curvature. It is well known that 15 of
the 27 exotic spheres in dimension 7 can be written as S^3 bundles over S^4 in
infinitely many ways, and hence we obtain infinitely many non-negatively
curved metrics on these exotic spheres. A further consequence will be that
there are infinitely many almost free actions by SO(3) on S^7, i.e. all
isotropy groups are finite. These actions preserve the Hopf fibration S^3 ->
S^7 -> S^4 but do not extend to the disc D^8. We also construct infinitely
many such actions on the 15 exotic 7-spheres mentioned above.

</DOC>
<DOC>
<DOCNO> 123303 </DOCNO>
Application of random walk theory to the first order Fermi acceleration


  We formulate the first order Fermi acceleration in parallel shock waves in
terms of the random walk theory. The formulation is applicable to any value of
the shock speed and the particle speed, in particular to the acceleration in
relativistic shocks, as long as large angle scattering is suitable for the
scattering process of particles. We first show that the trajectory of a
particle suffering from large angle scattering can be treated as a random walk
in a moving medium with an absorbing boundary (e.g., the shock front). We
derive an integral equation to determine the density of scattering points of
the random walk, and by solving it approximately we obtain approximate
solutions of the probability density of pitch angle at and the return
probability after the shock crossing in analytical form. These approximate
solutions include corrections of several non-diffusive effects to the
conventional diffusion approximation and we show that they agree well with the
Monte Carlo results for isotropic scattering model for any shock speed and
particle speed. Finally, we give an analytical expression of the spectral index
of accelerated particles in parallel shocks valid for arbitrary shock speed.

</DOC>
<DOC>
<DOCNO> 119440 </DOCNO>
X-rays from Quiescent Low-Mass X-ray Binary Transients


  I argue that it is very unlikely that X-rays from quiescent black-hole
low-mass X-ray binary transients are emitted by coronae of companion stars. I
show that in a simple model in which these X-rays are emitted by an ADAF
filling the inner part of an unsteady, dwarf-nova type disc, the X-ray
luminosity is correlated with the orbital period. I predict what values of
X-ray luminosities from black-hole transient systems should be observed by
Chandra and XMM-Newton.

</DOC>
<DOC>
<DOCNO> 122976 </DOCNO>
The 2dF Galaxy Redshift Survey: The Number and Luminosity Density of


  We present the bivariate brightness distribution (BBD) for the 2dF Galaxy
Redshift Survey (2dFGRS) based on a preliminary subsample of 45,000 galaxies.
The BBD is an extension of the galaxy luminosity function incorporating surface
brightness information. It allows the measurement of the local luminosity
density, j_B, and the galaxy luminosity and surface brightness distributions
while accounting for surface brightness selection biases. The recovered 2dFGRS
BBD shows a strong surface brightness-luminosity relation (M_B~2.4\mu_e). The
luminosity-density is dominated by normal galaxies and the luminosity-density
peak lies away from the selection boundaries implying that the 2dFGRS is
complete and that luminous low surface brightness galaxies are rare. The final
value we derive for the local luminosity-density, inclusive of surface
brightness corrections, is: j_B=2.49+/-0.20x10^8 h L_solar Mpc^-3.
Representative Schechter function parameters are: M*=-19.75+/-0.05,
phi*=2.02+/-0.02x10^-2 and alpha=-1.09+/-0.03. Extending the conventional
methodology to incorporate surface brightness selection effects has resulted in
an increase in the luminosity-density of 37%.

</DOC>
<DOC>
<DOCNO> 120385 </DOCNO>
Radiative Cooling Flows of Self-Gravitating Filamentary Clouds


  We study the dynamics of a self-gravitating cooling filamentary cloud using a
simplified model. We concentrate on the radial distribution and restrict
ourselves to quasi-hydrostatic, cylindrically symmetric cooling flows. For a
power-law dependence of cooling function on the temperature, self-similar
solutions which describe quasi-hydrostatic cooling flows are derived. We
consider obtically thin filaments with a constant mass per unit length and the
solutions are parameterized by their line masses. There is no polytropic
relation between the density and the pressure. The filament experiences
radiative condensation, irrespective of the \gamma, the gas specific heat
ratio. So, the filament becomes denser due to the quasi-hydrostatic flows and
the density at the center increases in proportion to (t_{0}-t)^{-1}, where t
denotes the time. The term, t_{0}, denotes an epoch at which the central
density increases infinitely. We also found that the radius of the filament
decreases in proportion to (t_{0}-t)^{0.5}.

</DOC>
<DOC>
<DOCNO> 9200 </DOCNO>
Spin-flip transitions between Zeeman sublevels in semiconductor quantum


  We have studied spin-flip transitions between Zeeman sublevels in GaAs
electron quantum dots. Several different mechanisms which originate from
spin-orbit coupling are shown to be responsible for such processes.
 It is shown that spin-lattice relaxation for the electron localized in a
quantum dot is much less effective than for the free electron. The spin-flip
rates due to several other mechanisms not related to the spin-orbit interaction
are also estimated.

</DOC>
<DOC>
<DOCNO> 101223 </DOCNO>
On the geometric boundaries of hyperbolic 4-manifolds


  We provide, for hyperbolic and flat 3-manifolds, obstructions to bounding
hyperbolic 4-manifolds, thus resolving in the negative a question of Farrell
and Zdravkovska.

</DOC>
<DOC>
<DOCNO> 117641 </DOCNO>
Iron Gradients in Cooling Flow Galaxies and Groups


  Previous studies of the Fe abundances in the hot gas of galaxies and groups
have reported conflicting results with most studies finding very sub-solar Fe
abundances that disagree with standard theory. To investigate the possible role
of Fe abundance gradients on these measurements we present deprojection
analysis of the ROSAT PSPC data of 10 of the brightest cooling flow galaxies
and groups. The PSPC allows for spatially resolved spectral analysis on a
half-arcminute scale, and interesting constraints on both the temperatures and
Fe abundances are possible because the ~1 keV temperatures of these systems are
well matched to the bandpass of the PSPC. In 9 out of 10 systems we find clear
evidence that the Fe abundance decreases with increasing radius: Z_Fe ~1 solar
- (several) solar within the central radial bin (r < ~10 kpc) which decreases
to Z_Fe ~0.5 solar at the largest radii examined (r ~50-100 kpc). The Fe
abundances (and temperatures) are consistent with the average values for these
systems that we obtained in our previous analyses of the ASCA data using
multitemperature models which confirms that previous inferences of very
sub-solar Fe abundances from ASCA arise from the incorrect assumption of
isothermal gas and not the presence of Fe abundance gradients. We discuss why
this ``Fe Bias'' affects much more seriously the measurements of Z_Fe from ASCA
data than from ROSAT data. We show that the Fe abundance profiles for these
galaxies and groups are consistent with a gas-dynamical model where the gas is
enriched by stellar ejecta and supernovae in the ``solar supernova
proportion'', the stars formed with a Galactic IMF, and the gas is diluted by
mixing with primordial gas at large radii.

</DOC>
<DOC>
<DOCNO> 8567 </DOCNO>
Transport in quantum wells in the presence of interface roughness


  The effective Hamiltonian for two dimensional quantum wells with rough
interfaces is formally derived. Two new terms are generated. The first term is
identified to the local energy level fluctuations, which was introduced
phenomenologically in the literature for interface roughness scattering but is
now shown to be valid only for an infinite potential well or Hamiltonians with
one single length scale. The other term is shown to modulate the wavefunction
and cause fluctuations in the charge density. This will further reduce the
electron mobility to the magnitude that is close to the experimental result.

</DOC>
<DOC>
<DOCNO> 119560 </DOCNO>
Measuring cosmological bulk flows via the kinematic Sunyaev-Zeldovich


  We propose a new method to measure the possible large-scale bulk flows in the
Universe from the cosmic microwave background (CMB) maps from the upcoming
missions, MAP and Planck. This can be done by studying the statistical
properties of the CMB temperature field at many X-ray cluster positions. At
each cluster position, the CMB temperature fluctuation will be a combination of
the Sunyaev-Zeldovich (SZ) kinematic and thermal components, the cosmological
fluctuations and the instrument noise term. When averaged over many such
clusters the last three will integrate down, whereas the first one will be
dominated by a possible bulk flow component. In particular, we propose to use
all-sky X-ray cluster catalogs that should (or could) be available soon from
X-ray satellites, and then to evaluate the dipole component of the CMB field at
the cluster positions. We show that for the MAP and Planck mission parameters
the dominant contributions to the dipole will be from the terms due to the SZ
kinematic effect produced by the bulk flow (the signal we seek) and the
instrument noise (the noise in our signal). Computing then the expected
signal-to-noise ratio for such measurement, we get that at the 95 % confidence
level the bulk flows on scales >100h^{-1} Mpc can be probed down to the
amplitude of $< 200$ km/sec with the MAP data and down to only 30 km/sec with
the Planck mission.

</DOC>
<DOC>
<DOCNO> 101683 </DOCNO>
Classification of Elliptic Line Scrolls


  The classification of projective elliptic line scrolls with the description
of their singular loci is given. In particular we recover Atiyah Theorem by
using classical methods.

</DOC>
<DOC>
<DOCNO> 169786 </DOCNO>
Optimal Encryption of Quantum Bits


  We characterize the complete set of protocols that may be used to securely
encrypt n quantum bits using secret and random classical bits. In addition to
the application of such quantum encryption protocols to quantum data security,
our framework allows for generalizations of many classical cryptographic
protocols to quantum data. We show that the encrypted state gives no
information without the secret classical data, and that 2n random classical
bits are the minimum necessary for informationally secure quantum encryption.
Moreover, the quantum operations are shown to have a surprising structure in a
canonical inner product space. This quantum encryption protocol is a
generalization of the classical one time pad concept. A connection is made
between quantum encryption and quantum teleportation, and this allows for a new
proof of optimality of teleportation.

</DOC>
<DOC>
<DOCNO> 80904 </DOCNO>
Study of compact abelian lattice gauge theories


  This is a review, intended for lattice nonspecialists, of the studies of the
compact abelian gauge theories on the lattice performed by the Aachen lattice
field theory group. We discuss in particular the pure compact QED and a U(1)
lattice gauge theory with charged scalar and fermion fields in four and three
dimensions. Our data indicate that these lattice theories might define some
continuum field theories, or at least effective field theories with remarkable
nonperturbative properties like confinement and dynamical mass generation.

</DOC>
<DOC>
<DOCNO> 121704 </DOCNO>
The importance of anisotropic interstellar turbulence and


  Recent studies suggest that when magnetohydrodynamic (MHD) turbulence is
excited by stirring a plasma at large scales, the cascade of energy from large
to small scales is anisotropic, in the sense that small-scale fluctuations
satisfy the inequality k_parallel << k_perp, where k_parallel and k_perp are,
respectively, the components of a fluctuation's wave vector parallel and
perpendicular to the background magnetic field. Such anisotropic fluctuations
are very inefficient at scattering cosmic rays. Results based on the
quasilinear approximation for scattering of cosmic rays by anisotropic MHD
turbulence are presented and explained. The important role played by
molecular-cloud magnetic mirrors in confining and isotropizing cosmic rays when
scattering is weak is also discussed.

</DOC>
<DOC>
<DOCNO> 174439 </DOCNO>
Emission time scale of light particles in the system Xe+Sn at 50 AMeV. A


  Proton and deuteron correlation functions have been investigated with both
impact parameter and emission source selections. The correlations of the system
(129Xe + natSn) at 50 AMeV have been measured with the 4 pi INDRA which
provides a complete kinematical description of each event. The emission time
scale analyzed with a quantum model reveals the time sequence of the light
particles emitted by the projectile-like fragment. The short and constant
emission time of the proton, independent of the impact parameter, can be
attributed to a preequilibrium process.

</DOC>
<DOC>
<DOCNO> 40212 </DOCNO>
Determinations of |Vub| with inclusive techniques at LEP


  The charmless semileptonic decay branching fraction has been measured, using
inclusive techniques, by the Aleph, Delphi and L3 experiments at LEP. The
average of their results is 1.74 +/- 0.37 +/- 0.38 +/- 0.21 10-3. From this
result the value of the |Vub| element in the CKM mixing matrix has been
derived, using OPE predictions, obtaining: |Vub| = (4.13 +0.42/-0.47
(stat.+det.) +0.43/-0.48 (b->c syst.) +0.24/-0.25 (b->u syst.) +/- 0.02 (taub)
+/- 0.20 (HQE)) 10-3.

</DOC>
<DOC>
<DOCNO> 152373 </DOCNO>
Finite N AdS/CFT Correspondence for Abelian and Nonabelian Orbifolds,


  Although the AdS/CFT correspondence is rigorous only for an infinite $N \to
\infty$ stack of D3-branes, it can be fruitfully studied for finite $N$ as a
source of gauge structures and choices for chiral fermions and complex scalars
which solve the hierarchy problem by a conformal fixed point. We emphasize
orbifolds $AdS_5 \times S^5/\Gamma$ where the resulting GFT has ${\cal N} = 0$
supersymmetry. The fact that the complex scalars are prescribed by the
construction limits the possible spontaneous symmetry breaking. Both abelian
and nonabelian $\Gamma$ are illustrated by simple examples. An accurate $sin^2
\theta$ in electroweak unification can be obtained, suggesting that this
approach merits further study.

</DOC>
<DOC>
<DOCNO> 80945 </DOCNO>
Static correlation lengths in QCD at high temperature and finite density


  A brief review is given of the sign problem in finite density lattice QCD and
various attempts to overcome it. To date there is still no solution to this
problem which would work for realistic QCD. The main focus then is on the
deconfined phase, where QCD can be described by a dimensionally reduced
effective action. After summarizing derivation and validity of the effective
theory, it is demonstrated that it can be simulated efficiently in the presence
of a chemical potential for quarks $\mu/T\lsim 4$. Direct comparison of
simulations with imaginary and real $\mu$ suggests that equilibrium plasma
properties could be analytically continued from 4d QCD simulations at imaginary
$\mu$.

</DOC>
<DOC>
<DOCNO> 169728 </DOCNO>
Optimal quantum teleportation with an arbitrary pure state


  We derive the maximum fidelity attainable for teleportation using a shared
pair of d-level systems in an arbitrary pure state. This derivation provides a
complete set of necessary and sufficient conditions for optimal teleportation
protocols. We also discuss the information on the teleported particle which is
revealed in course of the protocol using a non-maximally entangled state.

</DOC>
<DOC>
<DOCNO> 13423 </DOCNO>
Effective Gauge Theories of Spin Systems


  A large variety of microscopic gauge theories can be written for
antiferromagnetic spin systems, including $U(1), SU(2)$, and $Z_N$. I consider
the question of the appropriate effective gauge theory for such systems. I show
that while an SU(N) anti-ferromagnet can be written microscopically as a Z_N
gauge theory, for unfrustrated systems, with a two-sublattice structure, there
is always an effective U(1) gauge field. The dispersion relation for the gauge
field is shown to depend on the presence or absence of charge-conjugation
symmetry. Frustrated systems can break the gauge group to a discrete group, but
this appears to always involve introducing a gap for the spinons.

</DOC>
<DOC>
<DOCNO> 12484 </DOCNO>
Self-Organization in a Granular Medium by Internal Avalanches


  Internal avalanches of grain displacements can be created inside a granular
material kept in a bin in two ways: (i) By removing a radomly selected grain at
the bottom of the bin (ii) By breaking a stable arch of grains clogging a hole
at the bottom of the bin. Repeated generations of such avalanches lead the
system to a steady state. The question asked, is this state a critical state as
that in Self-Organized Criticality? We review here some of the recent studies
on this problem using cellular automata as well as hard disc models.

</DOC>
<DOC>
<DOCNO> 152244 </DOCNO>
Supersymmetric Quantum Mechanics of Scattering


  In the quantum mechanics of collision problems we must consider scattering
states of the system. For these states, the wave functions do not remain in
Hilbert space, but they are expressible in terms of generalized functions of a
Gel'fand triplet. Supersymmetric quantum mechanics for dealing with the
scattering states is here proposed.

</DOC>
<DOC>
<DOCNO> 84757 </DOCNO>
Fiber Bundle Gauge Theories and "Field's Dilemma"


  We propose a distinction between the physical and the mathematical parts of
gauge field theories. The main problem we face is to uphold a strong and
meaningful criterion of what is physical. We like to call it "Field's dilemma",
referring to Hartry Field's nominalist proposal which we consider to be
inadaequate. The resolution to the dilemma, we believe, is implicitly provided
by the so-called fiber bundle formalism. We shall demonstrate, in detail, that
the bundle structure underlying modern quantum and gravitational gauge field
theories allows for a genuine distinction between the physically significant
and the merely mathematical parts of these theories.

</DOC>
<DOC>
<DOCNO> 102761 </DOCNO>
A few remarks on exact C(X)-algebras


  We extend in this paper several results of E. Kirchberg, S. Wassermann and
the author dealing with continuous fields of C*--algebras to the
semi-continuous case. We provide a new characterisation of separable lower
semi-continuity C*--bundles and we present exactness criteria for C(X)-algebras
and unital bisimplifiable Hopf \cst-algebras.

</DOC>
<DOC>
<DOCNO> 150976 </DOCNO>
String Theory : Where are we now?


  This is a brief overview on the current status of string theory for
non-specialists. The purpose is to give an aspect on the nature of string
theory as a unified theory of all interactions including quantum gravity and to
discuss future perspectives. Particular emphases are put on the mysteries why
string theory contains gravity and why it resolves the ultraviolet problems.

</DOC>
<DOC>
<DOCNO> 100642 </DOCNO>
KRS and determinantal ideals


  The first sections contain a survey of the application of the
Knuth-Robinson-Schensted corerspondence to the computation of Groebner bases of
determinantal ideals. We also set up a conceptual framework for this
application in terms of so-called "KRS invariants". Then we show that the
initial ideal of a determinantal ideal "defined by shape" is given by its KRS
image. We furthermore characterize those among these ideals that even have a
Groebner basis of products of minors, and show that they can be characterized
in terms of Greene's KRS invariants. Furthermore it is shown that for the ideal
generated by all t-minors the formation of initial ideal and symbolic power
commutes. The last section contains a discussion of potential KRS invariants
related to so-called 1-cogenerated ideals.

</DOC>
<DOC>
<DOCNO> 118958 </DOCNO>
Radio recombination lines from starburst galaxies : high and low density


  Radio recombination lines (RRL) at 8 GHz and 15 GHz detected from four
starburst galaxies are shown to arise in compact high density HII regions,
which are undetectable below ~4 GHz. Detection of an RRL at 1.4 GHz towards one
galaxy and upper limits in the other three are consistent with the presence of
an equal amount of low density diffuse gas. Continuum flux density measurements
using the GMRT will be important in constraining the properties of the diffuse
gas.

</DOC>
<DOC>
<DOCNO> 84895 </DOCNO>
General Relativity and Spatial Flows: I. Absolute Relativistic Dynamics


  Two complementary and equally important approaches to relativistic physics
are explained. One is the standard approach, and the other is based on a study
of the flows of an underlying physical substratum. Previous results concerning
the substratum flow approach are reviewed, expanded, and more closely related
to the formalism of General Relativity. An absolute relativistic dynamics is
derived in which energy and momentum take on absolute significance with respect
to the substratum. Possible new effects on satellites are described.

</DOC>
<DOC>
<DOCNO> 118405 </DOCNO>
Non-Linear Effects on the Angular Correlation Function


  Extracting the three dimensional power spectrum from the 2D distribution of
galaxies has become a standard tool of cosmology. This extraction requires some
assumptions about the scaling of the power spectrum with redshift; all
treatments to date assume a simple power law scaling. In reality, different
scales grow at different rates, due to non-linearities. We show that angular
surveys are sensitive to a weighted average of the power spectrum over a
distribution of redshifts, where the weight function varies with wavenumber. We
compute this weight function and show that it is fairly sharply peaked at
\bar{z}, which is a function of k. As long as the extracted power spectrum is
understood to be $P(k,\bar{z})$, the error introduced by non-linear scaling is
quantifiable and small. We study these effects in the context of the APM and
SDSS photometric surveys. In general the weight matrix is peaked at larger z
and is broader for deeper surveys, leading to larger (but still quantifiable)
errors due to non-linear scaling. The tools introduced here -- in particular
the weight function and effective redshift $\bar{z}$ -- can also be profitably
applied to plan surveys to study the evolution of the power spectrum.

</DOC>
<DOC>
<DOCNO> 69187 </DOCNO>
Contributions of vector-like quarks to radiative B meson decay


  We study the decay B\to X_s\gamma in a minimal extension of the standard
model with extra up- and down-type quarks whose left- and right-handed
components are both SU(2) singlets. Constraints on the extended
Cabibbo-Kobayashi-Maskawa matrix are obtained from the experimental results for
the branching ratio. Even if the extra quarks are too heavy to be detected in
near-future colliders, the branching ratio could have a value which is
non-trivially different from the prediction of the standard model.

</DOC>
<DOC>
<DOCNO> 120356 </DOCNO>
Precision Cosmology and the Density of Baryons in the Universe


  Big-bang Nucleosynthesis (BBN) and Cosmic Microwave Background (CMB)
anisotropy measurements give independent, accurate measurements of the baryon
density and can test the framework of the standard cosmology. Early CMB data
are consistent with the longstanding conclusion from BBN that baryons
constitute a small fraction of matter in the Universe, but may indicate a
slightly higher value for the baryon density. We clarify precisely what the two
methods determine, and point out that differing values for the baryon density
can indicate either an inconsistency or physics beyond the standard models of
cosmology and particle physics. We discuss other signatures of the new physics
in CMB anisotropy.

</DOC>
<DOC>
<DOCNO> 150474 </DOCNO>
Noncommutativities of D-branes and $\theta$-changing Degrees of Freedom


  It is known that when there are several D-branes, their space-time
coordinates in general become noncommutative. From the point of view of
noncommutative geometry, it reflects noncommutativity of the world volume of
the D-branes. On the other hand, as we showed in the previous work, in the
presence of the constant antisymmetric tensor field the momentum operators of
the D-branes have noncommutative structure. In the present paper, we
investigate a relation between these noncommutativities and the description of
D-branes in terms of the noncommutative Yang-Mills theory recently proposed by
Seiberg and Witten. It is shown that the noncommutativity of the Yang-Mills
theory, which implies that of the world volume coordinates, originates from
both noncommutativities of the transverse coordinates and momenta from the
viewpoint of the lower-dimensional D-branes. Moreover, we show that this
noncommutativity is transformed by coordinate transformations on the world
volume and thereby can be chosen in an arbitrary fixed value. We also make a
brief comment on a relation between this fact and a hidden symmetry of the IIB
matrix models.

</DOC>
<DOC>
<DOCNO> 117994 </DOCNO>
Constraints to the SSC model for Mkn 501


  We fit the SEDs of the TeV blazar Mkn 501 adopting the homogeneous
Synchrotron-Self Compton model to simultaneous X-ray and TeV spectra recently
become available. We present detailed model spectra calculated with the above
constraints and taking into account the absorption of TeV photons by the IR
background. We found that the curved TeV spectra can be naturally reproduced
even without IRB absorption. Taking IRB absorption into account changes the
required parameter values only slightly.

</DOC>
<DOC>
<DOCNO> 40493 </DOCNO>
Jet energy scale setting with "photon+Jet" events at LHC energies.


  It is shown in the paper that Pt activity limitation (modulus of the vector
sum) of all particle beyond "photon+Jet" system Pt^out leads to the noticeable
photon Pt - jet Pt disbalance decreasing. On a simultaneous restriction of the
cluster Pt and Pt^out from above it is possible to reach an acceptable balance
between photon Pt - jet Pt with a sufficient number of the photon Pt - jet Pt
events for the jet energy scale setting and hadron calorimeter calibratiom of
the CMS detector at LHC.

</DOC>
<DOC>
<DOCNO> 119746 </DOCNO>
Relativistic beaming effects in the spectra of cores and hotspots in


  We present the results of multi-wavelength observations of cores and hotspots
at L, C, X and U bands with the Very Large Array, of a matched sample of radio
galaxies and quasars selected from the Molonglo Reference Catalogue. We use
these observations to determine the spectra of cores and hotspots, and test the
unified scheme for radio galaxies and quasars. Radio cores have been detected
at all wavelengths in all the quasars in our sample, while only $\sim$ 50% of
the galaxies have detected cores in at least one wavelength. The degree of core
prominence in this sample is consistent with the unified scheme for radio
galaxies and quasars. A comparison of the distributions of the two-point
spectral index of the cores in our sample of lobe-dominated quasars (LDQs) with
a matched sample of core-dominated quasars (CDQs) shows that the distributions
for these two classes are significantly different, consistent with the
expectations of the unified scheme. The difference in the spectral indices of
the two hotspots on opposite sides are also significantly larger for quasars
than radio galaxies, as expected in the unified scheme. We also investigate the
relationship between the spectral index of the hotspots and redshift or
luminosity for our sample of sources.

</DOC>
<DOC>
<DOCNO> 120290 </DOCNO>
Heavy X-ray Absorption in Soft X-ray Weak Active Galactic Nuclei


  Recent ROSAT studies have identified a significant population of Active
Galactic Nuclei (AGN) that are notably faint in soft X-rays relative to their
optical fluxes. Are these AGN intrinsically X-ray weak or are they just highly
absorbed? Brandt, Laor & Wills have systematically examined the optical and UV
spectral properties of a well-defined sample of these soft X-ray weak (SXW) AGN
drawn from the Boroson & Green sample of all the Palomar Green AGN with z<0.5.
We present ASCA observations of three of these SXW AGN: PG 1011-040, PG
1535+547 (Mrk 486), and PG 2112+059. In general, our ASCA observations support
the intrinsic absorption scenario for explaining soft X-ray weakness; both PG
1535+547 and PG 2112+059 show significant column densities (N_H~10^22-10^23
cm^-2) of absorbing gas. Interestingly, PG 1011-040 shows no spectral evidence
for X-ray absorption. The weak X-ray emission may result from very strong
absorption of a partially covered source, or this AGN may be intrinsically
X-ray weak. PG 2112+059 is a Broad Absorption Line (BAL) QSO, and we find it to
have the highest X-ray flux known of this class. It shows a typical power-law
X-ray continuum above 3 keV; this is the first direct evidence that BAL QSOs
indeed have normal X-ray continua underlying their intrinsic absorption.
Finally, marked variability between the ROSAT and ASCA observations of PG
1535+547 and PG 2112+059 suggests that the soft X-ray weak designation may be
transient, and multi-epoch 0.1-10.0 keV X-ray observations are required to
constrain variability of the absorber and continuum.

</DOC>
<DOC>
<DOCNO> 8932 </DOCNO>
Moments of the ARPES spectral function of an undoped Mott insulator


  We derive analytic expressions for the first three frequency moments of the
single particle spectral function for one hole in a Mott insulator in terms of
equilibrium spin correlation functions of the insulating state. We show that
the ``remnant Fermi surface`` detected in ARPES experiments is, in fact, a
reflection of the strong antiferromagnetic correlations of the system, {\it
not} a reflection of the original band-structure Fermi surface. We suggest that
ARPES data could be used to measure the magnetic specific heat.

</DOC>
<DOC>
<DOCNO> 119857 </DOCNO>
On the Internal Structure of Relativistic Jets


  A magnetohydrodynamic model is constructed for a cylindrical jet immersed in
an external uniform magnetic field. It is shown that, as in the force-free
case, the total electric current within the jet can be zero. The particle
energetics and the magnetic field structure are determined in a self-consistent
way; all jet parameters depend on the physical conditions in the external
medium. In particular, we show that a region with subsonic flow can exist in
the central jet regions. In actual relativistic jets, most of the energy is
transferred by the electromagnetic field only when the magnetization parameter
is sufficiently large, $\sigma>10^6$. We also show that, in general, the
well-known solution with a central core, $B_z = B_0/(1+\varpi^2/\varpi_c^2)$,
can not be realized in the presence of an external medium.

</DOC>
<DOC>
<DOCNO> 121619 </DOCNO>
The So-Called "Bar" in the Large Magellanic Cloud


  The off-centered "bar" of the Large Magellanic Cloud (LMC) is commonly
assumed, for simplicity's sake, to lie in the same plane as the LMC disk.
Relaxing this assumption to the extent allowed by the observations, we can
drastically change our interpretation of the microlensing events towards the
LMC. We propose that the off-centered ``bar'' in the Large Magellanic Cloud is
a foreground object slightly misaligned with, and offset from, the plane of the
LMC disk. The small displacement and misalignment are consequences of recent
tidal interactions with the Small Magellanic Cloud and the Galaxy. This
proposal, though radical, is consistent with the kinematics of the LMC and
near-infrared star count maps from the DENIS and 2MASS surveys. It does not
violate any of the observational limits on the depth and structure of the LMC
-- in particular, the reported 25 to 50 degree inclination range of the LMC and
the east-west gradient of distance moduli of standard candles. Contributions to
LMC microlensing come from the mutual lensing of stars in the disk and the
``bar'', as well as self-lensing of the disk and the ``bar''. The microlensing
optical depth of such configurations from self-lensing alone is comparable to
the observed microlensing signal reported by the EROS and MACHO groups.
Possible observations are suggested to discriminate between our misaligned,
offset ``bar'' model and the conventional picture of an off-centered, planar
bar.

</DOC>
<DOC>
<DOCNO> 100516 </DOCNO>
G\'eom\'etrie de l'espace tangent sur l'hyperbolo\"ide quantique


  We introduce the tangent space on a quantum hyperboloid. We define an action
of this tangent space on the corresponding "quantum function space" ${\cal A}$,
what converts the elements of the tangent space into "braided vector fields".
The tangent space is shown to be a projective ${\cal A}$-module and we define a
quantum (pseudo)metric and a quantum connection (partially defined) on it.

</DOC>
<DOC>
<DOCNO> 12124 </DOCNO>
Spectral ergodicity and normal modes in ensembles of sparse matrices


  We investigate the properties of sparse matrix ensembles with particular
regard for the spectral ergodicity hypothesis, which claims the identity of
ensemble and spectral averages of spectral correlators. An apparent violation
of the spectral ergodicity is observed. This effect is studied with the aid of
the normal modes of the random matrix spectrum, which describe fluctuations of
the eigenvalues around their average positions. This analysis reveals that
spectral ergodicity is not broken, but that different energy scales of the
spectra are examined by the two averaging techniques. Normal modes are shown to
provide a useful complement to traditional spectral analysis with possible
applications to a wide range of physical systems.

</DOC>
<DOC>
<DOCNO> 39718 </DOCNO>
Mixing of B mesons and Decay Constants with the Non-Perturbatively


  Several quantities relevant to phenomenological studies of the mixing of
neutral B mesons are computed on the lattice. Our main results are: f_{Bd}
sqrt(B_{Bd})=206(28)(7) MeV, f_{Bs} sqrt(B_{Bs})/f_{Bd}sqrt(B_{Bd})=1.16(7). We
also obtain the related quantities f_{Bs}sqrt(B{Bs})=237(18)(8) MeV, f_{Bd}=
174(22)(+7-0)(-4-0) MeV, f_{Bs}= 204(15)(+7-0)(+3-0) MeV,
f_{Bs}/f_{Bd}=1.17(4)(+0-1), f_{Bd}/f_{Ds}=0.74(5). After combining our results
with the experimental world average (Delta m_d), we predict (Delta
m_s)=15.8(2.1)(3.3) ps^{-1}. We have also computed the relevant parameters for
mixing of neutral D mesons which may be useful in some extensions of the
Standard Model. All the quantities were obtained from a quenched simulation
with a non-perturbatively improved Clover action at beta=6.2, corresponding to
a lattice spacing 1/a=2.7(1) GeV, on a sample of 200 gauge-field
configurations. A discussion of the main systematic errors is also presented.

</DOC>
<DOC>
<DOCNO> 40010 </DOCNO>
Searching for Narrow Graviton Resonances with the ATLAS Detector at the


  A spectrum of massive graviton states is present in several recent
theoretical models that include extra space dimensions. In some such models the
graviton states are well separated in mass, and can be detected as resonances
in collider experiments. The ability of the ATLAS detector at the Large Hadron
Collider to identify such states and measure their properties is considered, in
the case that the resonances are narrow compared to the experimental
resolution. The discovery limits for the detection of the decay mode G->e+e-
are derived. The angular distribution of the lepton pair is used to determine
the spin of the intermediate state. In one specific model, the resonance can be
detected up to a graviton resonance mass of 2080 GeV, while the angular
distribution favours a spin-2 hypothesis over a spin-1 hypothesis at 90%
confidence for resonance masses up to 1720 GeV.

</DOC>
<DOC>
<DOCNO> 70658 </DOCNO>
Bounds on Heavy-to-Heavy Weak Decay Form Factors


  We provide upper and lower bounds on the semileptonic weak decay form factors
for $B \to D^(*)$ and $\Lambda_b \to \Lambda_c$ decays by utilizing inclusive
heavy quark effective theory sum rules. These bounds are calculated to second
order in $\Lambda_{QCD}/m_Q$ and first order in $\alpha_s$. The $O(\alpha_s^2
\beta_0)$ corrections to the bounds at zero recoil are also presented.

</DOC>
<DOC>
<DOCNO> 102074 </DOCNO>
Nonlinearity, Local and Global Avalanche Characteristics of Balanced


  First, we construct a class of functions with good local avalanche
characteristics, but bad global avalanche characteristics. We also derive some
bounds for the nonlinearity of such functions. It improves upon the results of
Son et al., and Sung et al. In our second result we construct a class of highly
nonlinear balanced functions with good local and global avalanche
characteristics.

</DOC>
<DOC>
<DOCNO> 152234 </DOCNO>
Discrete Torsion, Non-Abelian Orbifolds and the Schur Multiplier


  Armed with the explicit computation of Schur Multipliers, we offer a
classification of SU(n) orbifolds for n = 2,3,4 which permit the turning on of
discrete torsion. This is in response to the host of activity lately in vogue
on the application of discrete torsion to D-brane orbifold theories. As a
by-product, we find a hitherto unknown class of N = 1 orbifolds with non-cyclic
discrete torsion group. Furthermore, we supplement the status quo ante by
investigating a first example of a non-Abelian orbifold admitting discrete
torsion, namely the ordinary dihedral group as a subgroup of SU(3). A
comparison of the quiver theory thereof with that of its covering group, the
binary dihedral group, without discrete torsion, is also performed.

</DOC>
<DOC>
<DOCNO> 118843 </DOCNO>
The Multiply Scattering Effect on the Energy Measurement of UHE Cosmic


  Point sources in the atmosphere are surrounded by aureole because of
atmospheric scattering. The properties of the time-dependent aureole radiance
are calculated by use of a Monte Carlo approach and an iterative method. Since
the aureole is particularly important in the ultraviolet, which is the region
the Ultra-High-Energy (UHE) cosmic ray experiment using the air fluorescence
technique like Fly's Eye or High-Resolution-Fly's-Eye(HiRes) are set in. The
effect of the multiply scatteing on the energy measurement is studied.

</DOC>
<DOC>
<DOCNO> 69048 </DOCNO>
Overview of Neutrino Oscillation Physics


  Recent evidence for neutrino oscillations has revolutionized the study of
neutrino masses and mixing. This report gives an overview of what we are
learning from the neutrino oscillation experiments, the prospects for the near
term, and the bright future of neutrino mass studies.

</DOC>
<DOC>
<DOCNO> 117400 </DOCNO>
Cosmological SPH simulations with four million particles: statistical


  We present results from a series of cosmological SPH (smoothed particle
hydrodynamics) simulations coupled with the P3M
(Particle-Particle-Particle-Mesh) solver for the gravitational force. The
simulations are designed to predict the statistical properties of X-ray
clusters of galaxies as well as to study the formation of galaxies. We have
seven simulation runs with different assumptions on the thermal state of the
intracluster gas. Following the recent work by Pearce et al., we modify our SPH
algorithm so as to phenomenologically incorporate the galaxy formation by
decoupling the cooled gas particles from the hot gas particles. All the
simulations employ 128^3 particles both for dark matter and for gas components,
and thus constitute the largest systematic catalogues of simulated clusters in
the SPH method performed so far. These enable us to compare the analytical
predictions on statistical properties of X-ray clusters against our direct
simulation results in an unbiased manner. We find that the luminosities of the
simulated clusters are quite sensitive to the thermal history and also to the
numerical resolution of the simulations, and thus are not reliable. On the
other hand, the mass-temperature relation for the simulated clusters is fairly
insensitive to the assumptions of the thermal state of the intracluster gas,
robust against the numerical resolution, and in fact agrees well with the
analytic prediction. Therefore the prediction for the X-ray temperature
function of clusters on the basis of the Press-Schechter mass function and the
virial equilibrium is fairly reliable.

</DOC>
<DOC>
<DOCNO> 122990 </DOCNO>
Modeling of C stars with core/mantle grains: Amorphous carbon + SiC


  A set of 45 dust envelopes of carbon stars has been modeled. Among them, 34
were selected according to their dust envelope class (as suggested by Sloan,
Little-Marenin & Price, 1998) and 11 are extreme carbon stars. The models were
performed using a code that describes the radiative transfer in dust envelopes
considering core/mantle grains composed by an alpha-SiC core and an amorphous
carbon (A.C.) mantle. In addition, we have also computed models with a code
that considers two kinds of grains - alpha-SiC and A.C. - simultaneously.
Core-mantle grains seem to fit dust envelopes of evolved carbon stars, while
two homogeneous grains are more able to reproduce thinner dust envelopes. Our
results suggest that there exists an evolution of dust grains in the carbon
star sequence. In the beginning of the sequence, grains are mainly composed of
SiC and amorphous carbon; with dust envelope evolution, carbon grains are
coated in SiC. This phenomena could perhaps explain the small quantity of SiC
grains observed in the interstellar medium. However, in this work we consider
only alpha-SiC grains, and the inclusion of beta-SiC grains can perhaps change
some of there results.

</DOC>
<DOC>
<DOCNO> 40632 </DOCNO>
New R values in 2-5 GeV from the BESII at BEPC


  We report preliminary $R$ values for all 85 energy points scanned in the
energy region of 2-5 GeV with the upgraded Beijing Spectrometer (BESII) at the
Beijing Electron Positron Collider (BEPC). The typical uncertainty on the R
values we measured is about 7%. The new R values have a significant impact on
the predicted mass of the Higgs coming from the global fit to the electroweak
data, and will also contribute to the interpretation of the E821 g-2
experiment.

</DOC>
<DOC>
<DOCNO> 13407 </DOCNO>
CaB_6: a new semiconducting material for spin electronics


  Ferromagnetism was recently observed at unexpectedly high temperatures in
La-doped CaB_6. The starting point of all theoretical proposals to explain this
observation is a semimetallic electronic structure calculated for CaB_6 within
the local density approximation. Here we report the results of parameter-free
quasiparticle calculations of the single-particle excitation spectrum which
show that CaB_6 is not a semimetal but a semiconductor with a band gap of 0.8
eV. Magnetism in La_xCa_{1-x}B_6 occurs just on the metallic side of a Mott
transition in the La-induced impurity band.

</DOC>
<DOC>
<DOCNO> 100736 </DOCNO>
Who Wins Domineering on Rectangular Boards?


  Using mostly elementary considerations, we find out who wins the game of
Domineering on all rectangular boards of width 2, 3, 5, and 7. We obtain bounds
on other boards as well, and prove the existence of polynomial-time strategies
for playing on all boards of width 2, 3, 4, 5, 7, 9, and 11. We also comment
briefly on toroidal and cylindrical boards.

</DOC>
<DOC>
<DOCNO> 117219 </DOCNO>
Elastic and Inelastic Evanescent-Wave Mirrors for Cold Atoms


  We report on experiments on an evanescent-wave mirror for cold $^{87}$Rb
atoms. Measurements of the bouncing fraction show the importance of the Van der
Waals attraction to the surface. We have directly observed radiation pressure
parallel to the surface, exerted on the atoms by the evanescent-wave mirror. We
analyze the radiation pressure by imaging the motion of the atom cloud after
the bounce. The number of photon recoils ranges from 2 to 31. This is
independent of laser power, inversely proportional to the detuning and
proportional to the evanescent-wave decay length. By operating the mirror on an
open transition, we have also observed atoms that bounce inelastically due to a
spontaneous Raman transition. The observed distributions consist of a dense
peak at the minimum velocity and a long tail of faster atoms, showing that the
transition is a stochastic process with a strong preference to occur near the
turning point of the bounce.

</DOC>
<DOC>
<DOCNO> 151251 </DOCNO>
On Renormalization Group in Abstract QFT


  The basics of RG equations for generic partition functions are briefly
reviewed, keeping in mind an application to the Polyakov-de Boer-Verlindes
description of the holomorphic RG flow.

</DOC>
<DOC>
<DOCNO> 70547 </DOCNO>
Two-Loop Master Integrals for $\gamma^* \to 3$ Jets: The planar


  The calculation of the two-loop corrections to the three jet production rate
and to event shapes in electron-positron annihilation requires the computation
of a number of up to now unknown two-loop four-point master integrals with one
off-shell and three on-shell legs. In this paper, we compute those master
integrals which correspond to planar topologies by solving differential
equations in the external invariants which are fulfilled by the master
integrals. We obtain the master integrals as expansions in $\e=(4-d)/2$, where
$d$ is the space-time dimension. The results are expressed in terms of newly
introduced two-dimensional harmonic polylogarithms, whose properties are
shortly discussed. For all two-dimensional harmonic polylogarithms appearing in
the divergent parts of the integrals, expressions in terms of Nielsen's
polylogarithms are given. The analytic continuation of our results to other
kinematical situations is outlined.

</DOC>
<DOC>
<DOCNO> 13580 </DOCNO>
Probability-Changing Cluster Algorithm for Potts Models


  We propose a new effective cluster algorithm of tuning the critical point
automatically, which is an extended version of Swendsen-Wang algorithm. We
change the probability of connecting spins of the same type, $p = 1 - e^{- J/
k_BT}$, in the process of the Monte Carlo spin update. Since we approach the
canonical ensemble asymptotically, we can use the finite-size scaling analysis
for physical quantities near the critical point. Simulating the two-dimensional
Potts models to demonstrate the validity of the algorithm, we have obtained the
critical temperatures and critical exponents which are consistent with the
exact values; the comparison has been made with the invaded cluster algorithm.

</DOC>
<DOC>
<DOCNO> 116361 </DOCNO>
Suppression of Magnetic State Decoherence Using Ultrafast Optical Pulses


  It is shown that the magnetic state decoherence produced by collisions in a
thermal vapor can be suppressed by the application of a train of ultrafast
optical pulses.

</DOC>
<DOC>
<DOCNO> 7889 </DOCNO>
Short-time dynamics and magnetic critical behavior of two-dimensional


  The critical behavior in the short-time dynamics for the random-bond Potts
ferromagnet in two-dimensions is investigated by short-time dynamic Monte Carlo
simulations. The numerical calculations show that this dynamic approach can be
applied efficiently to study the scaling characteristic, which is used to
estimate the critical exponents theta, beta/nu and z for the quenched disorered
systems from the power-law behavior of the kth moments of magnetizations.

</DOC>
<DOC>
<DOCNO> 100311 </DOCNO>
The Aspinwall-Morrison calculation and Gromov-Witten theory


  We prove the Aspinwall-Morrison formula by relating their calculation to
Gromov-Witten theory.

</DOC>
<DOC>
<DOCNO> 40468 </DOCNO>
Twist-three analysis of photon electroproduction with pion


  We study twist-three effects in spin, charge, and azimuthal asymmetries in
deeply virtual Compton scattering on a spin-zero target. Contributions which
are power suppressed in 1/Q generate a new azimuthal angle dependence of the
cross section which is not present in the leading twist results. On the other
hand the leading twist terms are not modified by the twist three contributions.
They may get corrected at twist four level. In the Wandzura-Wilczek
approximation these new terms in the Fourier expansion with respect to the
azimuthal angle are entirely determined by the twist-two skewed parton
distributions. We also discuss more general issues like the general form of the
angular dependence of the differential cross section, validity of factorization
at twist-three level, and a relation of skewed parton distributions to spectral
functions.

</DOC>
<DOC>
<DOCNO> 72272 </DOCNO>
Radiative Corrections to Chargino Production with Polarized Beams


  We show that radiative corrections to chargino production in
electron-positron annihilation with polarized beams can be large especially in
the case of right handed electrons. In addition, there is some dependency on
the squark masses that allows us to extract information about the squark
spectrum from the chargino production.

</DOC>
<DOC>
<DOCNO> 68289 </DOCNO>
The QCD Potential at $O(1/m)$


  Within an effective field theory framework, we obtain an expression for the
next-to-leading term in the $1/m$ expansion of the singlet $Q{\bar Q}$ QCD
potential in terms of Wilson loops, which holds beyond perturbation theory. The
ambiguities in the definition of the QCD potential beyond leading order in
$1/m$ are discussed and a specific expression for the $1/m$ potential is given.
We explicitly evaluate this expression at one loop and compare the outcome with
the existing perturbative results. On general grounds we show that for quenched
QED and fully Abelian-like models this expression exactly vanishes.

</DOC>
<DOC>
<DOCNO> 70103 </DOCNO>
Deconfinement through Chiral Symmetry Restoration in Two-Flavour QCD


  We propose that in QCD with dynamical quarks, colour deconfinement occurs
when an external field induced by the chiral condensate strongly aligns the
Polyakov loop. This effect sets in at the chiral symmetry restoration
temperature T-chi and thus makes deconfinement and chiral symmetry restoration
coincide. The predicted singular behaviour of Polyakov loop susceptibilities at
T-chi is shown to be supported by finite temperature lattice calculations.

</DOC>
<DOC>
<DOCNO> 120886 </DOCNO>
Stellar Collisions and Pulsar Planets


  I describe models for the formation of planetary systems surrounding the
remnants of stellar mergers and collisions. I focus primarily on models for the
viscous evolution of disks suitable for the formation of the planets
surrounding the pulsar B1257+12. I show that the adaptation of models for
traditional protoplanetary disks which invoke quiescent or `dead' zones are
quite successful in producing disks appropriate for the formation of the pulsar
planets. I also briefly describe some even more exotic possibilities that may
arise from compact object mergers.

</DOC>
<DOC>
<DOCNO> 152390 </DOCNO>
Stable Non-BPS States and Their Holographic Duals


  Stable non-BPS states can be constructed and studied in a variety of contexts
in string theory. Here we review some interesting constructions that arise from
suspended and wrapped branes. We also exhibit some stable non-BPS states that
have holographic duals.

</DOC>
<DOC>
<DOCNO> 72258 </DOCNO>
Light sigma-Meson Production in Excited Upsilon Decay Processes I:


  We analyze the pi pi production amplitudes in the excited Upsilon decay
processes, Upsilon(2S)-->Upsilon(1S)pi+pi-, Upsilon(3S)-->Upsilon(1S)pi+pi- and
Upsilon(3S)-->Upsilon(2S)pi+pi-, and the pi pi and KKbar production amplitudes
in the charmonium decay processes, psi(2S)-->J psi pi+pi- and J psi-->phi
pi+pi-, phi K+K-. The amplitudes are parametrized by the sum of Breit-Wigner
amplitudes for the sigma and the other relevant particles and of the direct
2pi-production amplitude, following the VMW method. All the pi pi (and KKbar)
invariant mass spectra are reproduced well with the sigma Breit-Wigner
amplitude by using the common parameters, m_sigma=526^(+48)_(-37) MeV and
Gamma_sigma =301^(+145)_(-100) MeV, which is almost consistent with the values
obtained in our previous phase shift analyses. This strongly suggests the
existence of light sigma-meson.

</DOC>
<DOC>
<DOCNO> 85288 </DOCNO>
Spontaneous loss of charge of the Reissner-Nordstrom black hole


  In this paper, we study by a functional method the vacuum instability of a
charged scalar field, when it is quantized in the background of the
Reissner-Nordtrom black hole; we also show that the first stage of the
evaporation process of the black hole can be driven by a Schwinger-like effect.

</DOC>
<DOC>
<DOCNO> 116488 </DOCNO>
Influence of Random Irregularities on Quasi-Thermal Noise Spectrum of


  The influence of random irregularities of electron density on quasi-thermal
noise spectra in plasma is considered in the paper. Quasi-thermal noise
spectrum of plasma in state near the thermal equilibrium is determined by
effective dielectric constant tensor. Presence of random irregularities change
dispersion law in plasma what cause the change in the shape of quasi-thermal
noise spectrum. Numerical estimation of noise spectra are fulfilled for both
conditions of ionospheric and solar wind plasma.

</DOC>
<DOC>
<DOCNO> 121322 </DOCNO>
Structural Model of Molecular Cloud Complexes: Mass, Size, and External


  We investigate the structure of the molecular cloud complexes (MCCs) as a
group of several giant molecular clouds (GMCs) in the Galaxy. Then, we find
that the mass-size relation which has been reported for the GMCs establishes
well even for the very large MCCs whose size is about 1 kpc. Since the
horizontal size of the MCCs is more than the thickness of the Galactic disk, we
can no longer consider the MCCs to be a sphere. Thus, we construct a structural
model of the MCCs, adopting a rectangular-solid geometry. As a result, our
model explains the observed mass-size relation of the MCCs very well. {}From
the estimated external pressure around the MCCs, we find that they are in a
rough pressure balance with the interstellar medium. Moreover, we find there is
observational deficiency of the MCCs with a large size and surface density.
Then, we suggest that the external pressure has a significant effect on the
structure and evolution of the MCCs. We also discuss the effect of H {\sc ii}
regions in the MCCs.

</DOC>
<DOC>
<DOCNO> 121428 </DOCNO>
Radio-Variability in Radio-Quiet Quasars and Low-Luminosity AGN


  We report on two surveys of radio-weak AGN to look for radio variability. We
find significant variability with an RMS of 10-20% on a timescale of months in
radio-quiet and radio-intermediate quasars. This exceeds the variability of
radio cores in radio-loud quasars (excluding blazars), which vary only on a few
percent level. The variability in radio-quiet quasars confirms that the radio
emission in these sources is indeed related to the AGN. The most extremely
variable source is the radio-intermediate quasar III Zw 2 which was recently
found to contain a relativistic jet. In addition we find large amplitude
variabilities (up to 300% peak-to-peak) in a sample of nearby low-luminosity
AGN, Liners and dwarf-Seyferts, on a timescale of 1.5 years. The variability
could be related to the activity of nuclear jets responding to changing
accretion rates. Simultaneous radio/optical/X-ray monitoring also for
radio-weak AGN, and not just for blazars, is therefore a potentially powerful
tool to study the link between jets and accretion flows.

</DOC>
<DOC>
<DOCNO> 100951 </DOCNO>
On the geometric simple connectivity of open manifolds


  One proves that there exists an obstruction to an open simply connected
$n$-manifold of dimension $n\geq 5$ being geometrically simply connected. In
particular there exist uncountably many simply connected $n$-manifolds which
are not w.g.s.c. One proves that for $n\neq 4$ an $n$-manifold proper homotopy
equivalent to a w.g.s.c. polyhedron is w.g.s.c. (for $n=4$ it is only end
compressible). We analyze further the case $n=4$ and Po\'enaru's conjecture.

</DOC>
<DOC>
<DOCNO> 10791 </DOCNO>
Dynamical Monte Carlo Study of Equilibrium Polymers (II): The Role of


  We investigate by means of a number of different dynamical Monte Carlo
simulation methods the self-assembly of equilibrium polymers in dilute,
semidilute and concentrated solutions under good-solvent conditions. In our
simulations, both linear chains and closed loops compete for the monomers,
expanding on earlier work in which loop formation was disallowed. Our findings
show that the conformational properties of the linear chains, as well as the
shape of their size distribution function, are not altered by the formation of
rings. Rings only seem to deplete material from the solution available to the
linear chains. In agreement with scaling theory, the rings obey an algebraic
size distribution, whereas the linear chains conform to a Schultz--Zimm type of
distribution in dilute solution, and to an exponentional distribution in
semidilute and concentrated solution. A diagram presenting different states of
aggregation, including monomer-, ring- and chain-dominated regimes, is given.

</DOC>
<DOC>
<DOCNO> 69682 </DOCNO>
The Cosmological Constant Problem from a Brane-World Perspective


  We point out several subtleties arising in brane-world scenarios of
cosmological constant cancellation. We show that solutions with curvature
singularities are inconsistent, unless the contribution to the effective
four-dimentional cosmological constant of the physics that resolves the
singularities is fine-tuned. This holds for both flat and curved branes.
Irrespective of this problem, we then study an isolated class of flat solutions
in models where a bulk scalar field with a vanishing potential couples to a
3-brane. We give an example where the introduction of a bulk scalar potential
results in a nonzero cosmological constant. Finally we comment on the stability
of classical solutions of the brane system with respect to quantum corrections.

</DOC>
<DOC>
<DOCNO> 85653 </DOCNO>
A Cosmological Window on Trans-Planckian Physics


  In the framework of inflation, scales which nowadays correspond to large
scale structures were smaller than the Planck length at the beginning of
inflation. Therefore, measurements of CMBR anisotropy or surveys of galaxies
and of clusters of galaxies could help us to probe physics beyond the Planck
scale. In these proceedings, we study how the inflationary observables depend
on trans-Planckian physics. It is found that there exist cases where
adiabaticity can be violated and the primordial spectrum of the quantum
cosmological perturbations modified. These cases correspond to rather drastic
alterations of the dispersion relation. There exist also modifications of the
standard physics which leave the power spectrum unchanged and therefore which
are compatible with the data. In this sense, the presently available
observations already constrain trans-Planckian physics.

</DOC>
<DOC>
<DOCNO> 40354 </DOCNO>
Measurement and QCD Analysis of Jet Cross Sections in Deep-Inelastic


  Jet production is studied in the Breit frame in deep-inelastic
positron-proton scattering over a large range of four-momentum transfers 5 <
Q^2 < 15000 GeV^2 and transverse jet energies 7 < E_T < 60 GeV. The analysis is
based on data corresponding to an integrated luminosity of L_int \simeq 33
pb^(-1) taken in the years 1995-1997 with the H1 detector at HERA at a
center-of-mass energy sqrt(s)=300 GeV. Dijet and inclusive jet cross sections
are measured multi-differentially using k_perp and angular ordered jet
algorithms. The results are compared to the predictions of perturbative QCD
calculations in next-to-leading order in the strong coupling constant
alphas.QCD fits are performed in which alphas and the gluon density in the
proton are determined separately. The gluon density is found to be in good
agreement with results obtained in other analyses using data from different
processes. The strong coupling constant is determined to be
alphas(MZ)=0.1186+-0.0059. In addition an analysis of the data in which both
alphas and the gluon density are determined simultaneously is presented.

</DOC>
<DOC>
<DOCNO> 117200 </DOCNO>
Quantum SuperStrings and Quantized Fractal Space Time


  Though Quantum SuperString Theory has shown promise, there are some puzzling
features like the extra dimensions, which are curled up in the Kaluza-Klein
sense. On the other hand a recent formulation of what may be called Quantized
Fractal Space Time leads to a surprising interface with QSS - we deal with the
Planck length, the same number of extra dimensions and an identical
non-commutative geometry. It is shown that this is not accidental. On the
contrary it gives us insight into the otherwise inexplicable features of QSS.

</DOC>
<DOC>
<DOCNO> 85599 </DOCNO>
Rotational Instabilities in Post-Collapse Stellar Cores


  A core-collapse supernova might produce large amplitude gravitational waves
if, through the collapse process, the inner core can aquire enough rotational
energy to become dynamically unstable. In this report I present the results of
3-D numerical simulations of core collapse supernovae. These simulations
indicate that for some initial conditions the post-collapse inner core is
indeed unstable. However, for the cases considered, the instability does not
produce a large gravitational-wave signal.

</DOC>
<DOC>
<DOCNO> 85458 </DOCNO>
Quantization of the electromagnetic field outside static black holes and


  We discuss the Gupta-Bleuler quantization of the free electromagnetic field
outside static black holes in the Boulware vacuum. We use a gauge which reduces
to the Feynman gauge in Minkowski spacetime. We also discuss its relation with
gauges used previously. Then we apply the low-energy sector of this field
theory to investigate some low-energy phenomena. First, we discuss the response
rate of a static charge outside the Schwarzschild black hole in four
dimensions. Next, motivated by string physics, we compute the absorption cross
sections of low-energy plane waves for the Schwarzschild and extreme
Reissner-Nordstr\"om black holes in arbitrary dimensions higher than three.

</DOC>
<DOC>
<DOCNO> 69285 </DOCNO>
QCD at finite isospin density


  QCD at finite isospin chemical potential mu_I has no fermion sign problem and
can be studied on the lattice. We solve this theory analytically in two limits:
at low mu_I where chiral perturbation theory is applicable, and at
asymptotically high mu_I where perturbative QCD works. At low isospin density
the ground state is a pion condensate, whereas at high density it is a Fermi
liquid with Cooper pairing. The pairs carry the same quantum numbers as the
pion. This leads us to a conjecture that the transition from hadron to quark
matter is smooth, which passes several tests. Our results imply a nontrivial
phase diagram in the space of temperature and chemical potentials of isospin
and baryon number.

</DOC>
<DOC>
<DOCNO> 11594 </DOCNO>
The Emergence of Spatial Complexity in the immune System


  Biological systems, unlike physical or chemical systems, are characterized by
the very inhomogeneous distribution of their components. The immune system, in
particular, is notable for self-organizing its structure. Classically, the
dynamics of natural systems have been described using differential equations.
But, differential equation models fail to account for the emergence of
large-scale inhomogeneities and for the influence of inhomogeneity on the
overall dynamics of biological systems. Here, we show that a microscopic
simulation methodology enables us to model the emergence of large-scale objects
and to extend the scope of mathematical modeling in biology. We take a simple
example from immunology and illustrate that the methods of classical
differential equations and microscopic simulation generate contradictory
results. Microscopic simulations generate a more faithful approximation of the
reality of the immune system.

</DOC>
<DOC>
<DOCNO> 120365 </DOCNO>
On the Structure of the Magnetic Field in a Kinematic ABC Flow Dynamo


  The kinematic induction equation of MHD is solved numerically in the case of
the normal ``111'' ABC flow using a general staggered mesh method. Careful 3-D
visualizations of the topology of the magnetic field reveal that previous
conclusions about the modes of operation of this type of kinematic dynamo must
be revised. The two known windows of dynamo action at low and high magnetic
Reynolds number, correspond to two distinct modes, both relying crucially on
the replenishing of the magnetic field near a discontinuity at the beta-type
stagnation points in the flow. One of these modes display double magnetic
structures that were previously found only to obscure the physics of the
dynamo: They turn out, however, to play an important part in the process of
amplifying the magnetic field. Invariant properties of the mode in the second
magnetic Reynolds number window support the case for the normal ABC flow as a
fast dynamo.

</DOC>
<DOC>
<DOCNO> 116661 </DOCNO>
Asymptotic light field in the presence of a bubble-layer


  We report that the submerged microbubbles are an efficient source of diffuse
radiance and may contribute to a rapid transition to the diffuse asymptotic
regime. In this asymptotic regime an average cosine is easily predictable and
measurable.

</DOC>
<DOC>
<DOCNO> 11735 </DOCNO>
Characteristic length of random knotting for cylindrical self-avoiding


  We discuss the probability of random knotting for a model of self-avoiding
polygons whose segments are given by cylinders of unit length with radius $r$.
We show numerically that the characteristic length of random knotting is
roughly approximated by an exponential function of the chain thickness $r$.

</DOC>
<DOC>
<DOCNO> 121555 </DOCNO>
Magnetospheric Accretion and Winds on the T Tauri Star SU Aurigae:


  SU Aurigae is a T Tauri star that was well monitored during the MUSICOS 96
multi-site campaign. We present the results of the spectroscopic analysis of
the circumstellar environment of this star, particularly of the Halpha, Hbeta,
Na I D and He I D3 line profiles. The signatures of modulated outflows and mass
accretion events are analysed, as well as transient spectral features. We
compute the cross-correlation function (CCF) of several pairs of (velocity bins
in) spectral lines to better investigate the profiles' temporal variability. We
found increasing time lags between the variability of He I D3, Na I D and
Hbeta. We propose this may be understood in terms of azimuthal distortion of
the magnetic field lines due to the different rotation rates of the star and
the disk. We find the slightly blueshifted absorption features in Halpha, Hbeta
and Na I D to be anti-correlated with the accretion flow signatures. We propose
that the transient absorption features in the blue wings of Halpha, Hbeta and
Na I D (signatures of mass outflows), and flare brightenings are related to the
disruption of distorted magnetospheric field lines.

</DOC>
<DOC>
<DOCNO> 11509 </DOCNO>
Convergent Calculation of the Asymptotic Dimension of Diffusion Limited


  Diffusion Limited Aggregation (DLA) is a model of fractal growth that had
attained a paradigmatic status due to its simplicity and its underlying role
for a variety of pattern forming processes. We present a convergent calculation
of the fractal dimension D of DLA based on a renormalization scheme for the
first Laurent coefficient of the conformal map from the unit circle to the
expanding boundary of the fractal cluster. The theory is applicable from very
small (2-3 particles) to asymptotically large (n \to \infty) clusters. The
computed dimension is D=1.713\pm 0.003.

</DOC>
<DOC>
<DOCNO> 101937 </DOCNO>
Finite dimesional Hamiltonian formalism for gauge and field theories


  We discuss in this paper the canonical structure of classical field theory in
finite dimensions within the {\it{pataplectic}} Hamiltonian formulation, where
we put forward the role of Legendre correspondance. We define the generalized
Poisson $\mathfrak{p}$-brackets which are the analogues of the Poisson bracket
on forms. We formulate the equations of motion of forms in terms of
$\mathfrak{p}$-brackets. As illustration of our formalism we present three
examples: the interacting scalar fields, conformal string theory and the
electromagnetic field.

</DOC>
<DOC>
<DOCNO> 101019 </DOCNO>
Coherence, Homotopy and 2-Theories


  2-Theories are a canonical way of describing categories with extra structure.
2-theory-morphisms are used when discussing how one structure can be replaced
with another structure. This is central to categorical coherence theory. We
place a Quillen model category structure on the category of 2-theories and
2-theory-morphisms where the weak equivalences are biequivalences of
2-theories. A biequivalence of 2-theories (Morita equivalence) induces and is
induced by a biequivalence of 2-categories of algebras. This model category
structure allows one to talk of the homotopy of 2-theories and discuss the
universal properties of coherence.

</DOC>
<DOC>
<DOCNO> 118250 </DOCNO>
Radial Velocity Studies of Close Binary Stars.III


  Radial velocity measurements and simple sine-curve fits to the orbital
velocity variations are presented for the third set of ten contact binary
systems: CN And, HV Aqr, AO Cam, YY CrB, FU Dra, RZ Dra, UX Eri, RT LMi, V753
Mon, OU Ser. All systems but two are contact, double-line spectroscopic
binaries with four of them (YY CrB, FU Dra, V753 Mon, OU Ser) being the recent
discoveries of the Hipparcos satellite project. The most interesting object is
V753 Mon with the mass-ratio closest to unity among all contact systems (q =
0.970 pm 0.003) and large total mass ((M1+M2)sin^3i = 2.93 pm 0.06). Several of
the studied systems are prime candidates for combined light and radial-velocity
synthesis solutions.

</DOC>
<DOC>
<DOCNO> 118712 </DOCNO>
A far IR study of the CfA Seyfert sample. I. The data


  We present mid and far IR ISO data of the CfA Seyfert galaxy sample. These
data allow a detailed study of the far IR Spectral Energy Distribution (SED) of
these galaxies. A Bayesian inversion method has been used to invert the SED of
these sources yielding two fundamental results, namely, that the mid and far IR
SED of Seyfert galaxies can be explained solely through thermal reradiation of
high energy photons by dust, and that this thermal emission is made up of two
or three different independent components, a warm, a cold and a very cold dust
component. These thermal components have been readily explained as produced
respectively by warm dust heated by either the active nucleus or by
circumnuclear starburts, cold dust heated by star forming region in the galaxy
disk, and very cold dust heated by the general interstellar radiation field.
Comparisons between the parameters obtained from the analysis of the IR SEDs
(fluxes, temperatures, luminosities) have been made. Our results suggest that
the emission in the mid IR is anisotropic and the differences found between
Seyfert 1 and Seyfert 2s can be explained with thin molecular tori models.

</DOC>
<DOC>
<DOCNO> 80643 </DOCNO>
Percolation and Magnetization in the Continuous Spin Ising Model


  In the strong coupling limit the partition function of SU(2) gauge theory can
be reduced to that of the continuous spin Ising model with nearest neighbour
pair-interactions. The random cluster representation of the continuous spin
Ising model in two dimensions is derived through a Fortuin-Kasteleyn
transformation, and the properties of the corresponding cluster distribution
are analyzed. It is shown that for this model, the magnetic transition is
equivalent to the percolation transition of Fortuin-Kasteleyn clusters, using
local bond weights. These results are also illustrated by means of numerical
simulations.

</DOC>
<DOC>
<DOCNO> 169694 </DOCNO>
Security of classical noise-based cryptography


  We examine security of a protocol on cryptographic key distribution via
classical noise proposed by Yuen and Kim (Phys. Lett. A 241 135 (1998)).
Theoretical and experimental analysis in terms of the secure key distribution
rate shows that secure key distribution is possible even if the eavesdropper
could receive more photons than the legitimate receiver, as long as the
signal-to-noise-ratio (SNR) of the receiver is better than -9dB of the
eavesdropper's SNR. Secure key distribution was demonstrated at the maximum
rate of 0.04 bit per sender's bit and transmission rate of 2 Mb/s in the
experiment employing conventional fiber optics. The present protocol has
advantages of the efficient key distribution and the simple implementation over
other quantum key distribution protocols. However, careful design and
management are necessary to keep the security of the crypto-system.

</DOC>
<DOC>
<DOCNO> 85257 </DOCNO>
New family of inhomogeneous $\gamma$-law cosmologies: example of


  We present an explicit three-parameter class of $p=\gamma \varrho$,
($-1/3\leq\gamma<1$), cosmological models admitting a two-dimensional group
$G_{2}$ of isometries acting on spacelike surfaces. The family is self-similar
in the sense that it has a further homothetic vector field and it contains
subfamilies of both (previously unknown) tilted and non-tilted Bianchi models
with that equation of state. This is the first algebraically general class of
solutions of this kind including dust inhomogeneous solutions. The whole class
presents a universal spacelike big-bang singularity in the finite past. More
interestingly, the case $p=\varrho /3$ constitutes a new two-parameter
inhomogeneous subfamily which can be viewed as a Bianchi V background with a
gravitational wave travelling orthogonally to the surfaces of transitivity of
the $G_{2}$ group. This wave generates the {\it inhomogeneity} of the spacetime
and is related to the sound waves {\it tilting} the perfect fluid. It seems to
be the first explicit exact example of a gravitational wave travelling along a
homogeneous background that has a realistic equation of state $p=\varrho /3$.

</DOC>
<DOC>
<DOCNO> 120943 </DOCNO>
Modern Supernova Search


  Supernovae play a critical role in observational cosmology as well as in
astrophysics of stars and galaxies. Recent era has seen dramatic progress in
the research of supernovae. Several programs to search systematically
supernovae in nearby to distant galaxies have been very successful. Recent
progresses in the modern supernova search are reviewed.

</DOC>
<DOC>
<DOCNO> 69164 </DOCNO>
Heavy Quark Production and PDF's Subgroup Report


  We present a status report of a variety of projects related to heavy quark
production and parton distributions for the Tevatron Run II.

</DOC>
<DOC>
<DOCNO> 118435 </DOCNO>
An Improved Red Spectrum of the Methane or T-dwarf SDSS 1624+0029: Role


  A Keck~II low resolution spectrum shortward of ome-micron is presented for
SDSS 1624+0029, the first field methane or T dwarf discovered in the Sloan
Digital Sky Survey. Significant flux is detected down to the spectrum's short
wavelength limit of 6200\AA. The spectrum exhibits a broad absorption feature
centered at 7700\AA, which we interpret as the K~I 7665/7699 resonance doublet.
The observed flux declines shortward of 7000\AA, due most likely to the red
wing of the Na~I doublet. Both Cs~I doublet lines are detected more strongly
than in an earlier red spectrum. Neither Li~I absorption nor H$\alpha$ emission
are detected. An exploratory model fit to the spectrum suggests that the shape
of the red spectrum can be primarily accounted for by the broad wings of the
K~I and Na~I doublets. This behavior is consistent with the argument proffered
by Burrows, Marley and Sharp that strong alkali absorption is principally
responsible for depressing T dwarf spectra shortward of 1$\mu$m. In particular,
there seems no compelling reason at this time to introduce dust or an
additional opacity source in the atmosphere of the SDSS object. The width of
the K~I and strengths of the Cs~I lines also indicate that the Sloan object is
warmer than Gl~229B.

</DOC>
<DOC>
<DOCNO> 99570 </DOCNO>
Is Bootstrap Really Helpful in Point Process Statistics?


  There are some papers which describe the use of bootstrap techniques in point
process statistics. The aim of the present paper is to show that the form in
which bootstrap is used there is dubious. In case of variance estimation of
pair correlation function estimators the used bootstrap techniques lead to
results which can be obtained simpler without simulation; furthermore, they
differ from the desired results. The problem to obtain confidence regions for
the intensity function of inhomogeneous Poisson processes can be easily solved
without bootstrap techniques.

</DOC>
<DOC>
<DOCNO> 118376 </DOCNO>
Effects of galaxy mergers on the faint IRAS source counts and the


  Binary merging constitutes a complementary mode of galaxy evolution to the
canonical hierarchical clustering theory. This merger-driven evolution not only
influences the galaxy mass distribution function, but may drive the main
galactic activity cycles, such as starbursts and the activity in the nuclei
(AGNs). In this paper, we use galaxy aggregation dynamics together with a
possible merger-driven starburst and AGN phenomena, to study the effects of
evlution of these consequential activities for the faint IRAS source counts and
the infra-red background. We find that the strong evolution of IRAS 60$ \mu m$
source count at flux range of $10 mJy \sim 1 Jy$ is difficult to be explained
only by the merger rate decrease with cosmic time. We need to assume a redshift
dependent infrared burst phase of ultraluminous infrared galaxies (ULIGs) from
the gas rich mergers at high redshift and the gas poor mergers at low redshift.
The background intensity at 60$ \mu m$ which we get from this aggregation
evolution is a lower limit of only $1.9 nW m^{-2} sr^{-1}$, about half of those
estimated by some previous models, but close to the lower end of the range
derived by Malkan & Stecker (1998).

</DOC>
<DOC>
<DOCNO> 70660 </DOCNO>
Effects of the Scale-dependent Vacuum Expectation Values in the


  The contribution of scale-dependent vacuum expectation values (VEVs) of Higgs
scalars, which gives significant effects in the evolution of fundamental
fermion masses in the Minimal Supersymmetric Standard Model (MSSM), is now
considered in the derivation of the one-loop analytic expression for the
evolution of the left-handed Majorana neutrino masses with energies. The
inclusion of such effect of the running VEV increases the stability of the
neutrino masses under quantum corrections and leads to a mild decrease of
neutrino masses with higher energies.

</DOC>
<DOC>
<DOCNO> 13815 </DOCNO>
Evaluation of the optical conductivity tensor in terms of contour


  For the case of finite life-time broadening the standard Kubo-formula for the
optical conductivity tensor is rederived in terms of Green's functions by using
contour integrations, whereby finite temperatures are accounted for by using
the Fermi-Dirac distribution function. For zero life-time broadening, the
present formalism is related to expressions well-known in the literature.
Numerical aspects of how to calculate the corresponding contour integrals are
also outlined.

</DOC>
<DOC>
<DOCNO> 10404 </DOCNO>
Cooper Pair Formation in U(1) Gauge Theory of High Temperature


  We study the two-dimensional spin-charge separated Ginzburg-Landau theory
containing U(1) gauge interactions as a semi-phenomenological model describing
fluctuating condensates in high temperature superconductivity. Transforming the
original GL action, we abstract the effective action of Cooper pair.
Especially, we clarify how Cooper pair correlation evolves in the normal state
from the point of view of spin-charge separation. Furthermore, we point out how
Cooper pair couples to gauge field in a gauge-invariant way, stressing the
insensitivity of Cooper pair to infrared gauge field fluctuation.

</DOC>
<DOC>
<DOCNO> 84159 </DOCNO>
Stochastically Fluctuating Black-Hole Geometry, Hawking Radiation and


  We study the propagation of null rays and massless fields in a black hole
fluctuating geometry. The metric fluctuations are induced by a small
oscillating incoming flux of energy. The flux also induces black hole mass
oscillations around its average value. We assume that the metric fluctuations
are described by a statistical ensemble. The stochastic variables are the
phases and the amplitudes of Fourier modes of the fluctuations. By averaging
over these variables, we obtain an effective propagation for massless fields
which is characterized by a critical length defined by the amplitude of the
metric fluctuations: Smooth wave packets with respect to this length are not
significantly affected when they are propagated forward in time. Concomitantly,
we find that the asymptotic properties of Hawking radiation are not severely
modified. However, backward propagated wave packets are dissipated by the
metric fluctuations once their blue shifted frequency reaches the inverse
critical length. All these properties bear many resemblences with those
obtained in models for black hole radiation based on a modified dispersion
relation. This strongly suggests that the physical origin of these models,
which were introduced to confront the trans-Planckian problem, comes from the
fluctuations of the black hole geometry.

</DOC>
<DOC>
<DOCNO> 12518 </DOCNO>
Friedel oscillations in a Luttinger liquid with long-range interactions


  We introduce a path-integral approach that allows to compute charge density
oscillations in a Luttinger liquid with impurities. We obtain an explicit
expression for the envelope of Friedel oscillations in the presence of
arbitrary electron-electron potentials. As examples, in order to illustrate the
procedure, we show how to use our formula for contact and Coulomb potentials.

</DOC>
<DOC>
<DOCNO> 122594 </DOCNO>
Monitoring and modeling radio flares from microquasars


  We present results of long-term daily monitoring of a sample of Galactic
radio-emitting X-ray binaries showing relativistic jets (RJXRB): SS433, Cyg
X-3, and GRS 1915+105, with the RATAN-600 radio telescope in the 0.6-22 GHz
range. We carried out the modeling calculations to understand the temporal
(1--100 days) and spectral (1-22 GHz) dependence. We tested the finite jet
segment models and we found that the geometry of the conical hollow jets is
responsible for either a power law or an exponential decay of the flares. SS433
was monitored for 100 days in 1997 and 120 days in 1999. From the quiescent
radio light curves, we obtained clear evidence of a 6.04-day 10-15% modulation.
Three powerful flares (up to 13 Jy) from Cyg X-3 were detected in April 2000.

</DOC>
<DOC>
<DOCNO> 118132 </DOCNO>
The Primordial Helium Abundance: Towards Understanding and Removing the


  We present results from photoionization models of low-metallicity HII
regions. These nebulae form the basis for measuring the primordial helium
abundance. Our models show that the helium ionization correction factor (ICF)
can be non-negligible for nebulae excited by stars with effective temperatures
larger than 40,000 K. Furthermore, we find that when the effective temperature
rises to above 45,000 K, the ICF can be significantly negative. This result is
independent of the choice of stellar atmosphere. However, if an HII region has
an [O III] 5007/[O I] 6300 ratio greater than 300, then our models show that,
regardless of its metallicity, it will have a negligibly small ICF. A similar,
but metallicity dependent, result was found using the [O III] 5007/H$\beta$
ratio. These two results can be used as selection criteria to remove nebulae
with potentially non-negligible ICFs. Using our metallicity independent
criterion on the data of Izotov & Thuan (1998) results in a 20% reduction of
the rms scatter about the best fit $Y-Z$ line. A fit to the selected data
results in a slight increase of the value of the primordial helium abundance.

</DOC>
<DOC>
<DOCNO> 102520 </DOCNO>
Categoricity in abstract elementary classes: going up inductive step


  We deal with stability theory for ``reasonable'' non-elementary classes
without any remanents of compactness (like: above Hanf number or definable by
L_{omega_1, omega}).

</DOC>
<DOC>
<DOCNO> 169810 </DOCNO>
Cavity induced modifications to the resonance fluorescence and probe


  A cavity-modified master equation is derived for a coherently driven, V-type
three-level atom coupled to a single-mode cavity in the bad cavity limit. We
show that population inversion in both the bare and dressed-state bases may be
achieved, originating from the enhancement of the atom-cavity interaction when
the cavity is resonant with an atomic dressed-state transition. The atomic
populations in the dressed state representation are analysed in terms of the
cavity-modified transition rates. The atomic fluorescence spectrum and probe
absorption spectrum also investigated, and it is found that the spectral
profiles may be controlled by adjusting the cavity frequency. Peak suppression
and line narrowing occur under appropriate conditions.

</DOC>
<DOC>
<DOCNO> 122748 </DOCNO>
The Extended X-ray Halo of the Crab-like SNR G21.5-0.9


  Recent XMM-Newton observations reveal an extended (150") low-surface
brightness X-ray halo in the supernova remnant G21.5-0.9. The near circular
symmetry, the lack of any limb brightening and the non-thermal spectral form,
all favour an interpretation of this outer halo as an extension of the central
synchrotron nebula rather than as a shell formed by the supernova blast wave
and ejecta. The X-ray spectrum of the nebula exhibits a marked spectral
softening with radius, with the power-law spectral index varying from Gamma =
1.63 +/- 0.04 in the core to Gamma = 2.45 +/- 0.06 at the edge of the halo.
Similar spectral trends are seen in other Crab-like remnants and reflect the
impact of the synchrotron radiation losses on very high energy electrons as
they diffuse out from the inner nebula. A preliminary timing analysis provides
no evidence for any pulsed X-ray emission from the core of G21.5-0.9.

</DOC>
<DOC>
<DOCNO> 116632 </DOCNO>
Simulation of Urban Effects of Cloud Physical Parameters


  A scale invariant, selfsimilar atmospheric eddy continuum exists in the
planetary atmospheric boundary layer spanning several orders of magnitude in
scales and gives rise to the observed fractal geometry for the global cloud
cover pattern. The global weather systems are manifestations of the unified
atmospheric eddy continuum with inherent mutual global-local energy exchange
and therefore local urban energy/pollution sources have long-range global
effects leading to climate change and environmental degradation. It is shown
that the observed scale invariant atmospheric eddy continuum originates from
the turbulence scale by the universal period doubling route to chaos eddy
growth phenomenon in the planetary atmospheric boundary layer. The cloud
dynamical, microphysical and electrical parameters are shown to be simple
unique functions of turbulence scale energy generation.

</DOC>
<DOC>
<DOCNO> 178808 </DOCNO>
Medium corrections in the formation of light charged particles in heavy


  Within a microscopic statistical description of heavy ion collisions, we
investigate the effect of the medium on the formation of light clusters. The
dominant medium effects are self-energy corrections and Pauli blocking that
produce the Mott effect for composite particles and enhanced reaction rates in
the collision integrals. Microscopic description of composites in the medium
follows the Dyson equation approach combined with the cluster mean-field
expansion. The resulting effective few-body problem is solved within a properly
modified Alt-Grassberger-Sandhas formalism. The results are incorporated in a
Boltzmann-Uehling-Uhlenbeck simulation for heavy ion collisions. The number and
spectra of light charged particles emerging from a heavy ion collision changes
in a significant manner in effect of the medium modification of production and
absorption processes.

</DOC>
<DOC>
<DOCNO> 11054 </DOCNO>
Double sign reversal of the vortex Hall effect in YBa2Cu3O7-delta thin


  Measurements of the Hall effect and the resistivity in twinned
YBa2Cu3O7-delta thin films in magnetic fields B oriented parallel to the
crystallographic c-axis and to the twin boundaries reveal a double sign
reversal of the Hall coefficient for B below 1 T. In high transport current
densities, or with B tilted off the twin boundaries by 5 degrees, the second
sign reversal vanishes. The power-law scaling of the Hall conductivity to the
longitudinal conductivity in the mixed state is strongly modified in the regime
of the second sign reversal. Our observations are interpreted as strong,
disorder-type dependent vortex pinning and confirm that the Hall conductivity
in high temperature superconductors is not independent of pinning.

</DOC>
<DOC>
<DOCNO> 72228 </DOCNO>
Q^2 evolution of parton distributions at small x. A study of


  We investigate the Q^2 evolution of parton distributions at small x values,
obtained in the case of flat initial conditions. The contributions of twist-two
and (renormalon-type) higher-twist operators of the Wilson operator product
expansion are taken into account. The results are in excellent agreement with
deep inelastic scattering experimental data from HERA.

</DOC>
<DOC>
<DOCNO> 151181 </DOCNO>
Exact solution of the supersymmetric sinh-Gordon model with boundary


  The boundary supersymmetric sinh-Gordon model is an integrable quantum field
theory in 1+1 dimensions with bulk N=1 supersymmetry, whose bulk and boundary S
matrices are not diagonal. We present an exact solution of this model. In
particular, we derive an exact inversion identity and the corresponding
thermodynamic Bethe Ansatz equations. We also compute the boundary entropy, and
find a rich pattern of boundary roaming trajectories corresponding to c < 3/2
superconformal models.

</DOC>
<DOC>
<DOCNO> 7913 </DOCNO>
Electron momentum distribution of a single mobile hole in the t-J model


  We investigate the electron momentum distribution function (EMDF) for the
two-dimensional t-J model. The results are based on the self-consistent Born
approximation (SCBA) for the self-energy and the wave function. In the Ising
limit of the model we give the results in a closed form, in the Heisenberg
limit the results are obtained numerically. An anomalous momentum dependence of
EMDF is found and the anomaly is in the lowest order in number of magnons
expressed analitycally. We interpret the anomaly as a fingerprint of an
emerging large Fermi surface coexisting with hole pockets.

</DOC>
<DOC>
<DOCNO> 152643 </DOCNO>
Exercising in K-theory: Brane Condensation without Tachyon


  We show that the p-dimensional noncommutative Yang--Mills model corresponding
to a (p-1)-brane allows solutions which correspond to lower branes. This may be
interpreted as the Morita equivalence of noncommutative planes of various
dimensions.

</DOC>
<DOC>
<DOCNO> 12565 </DOCNO>
Hole spin polarization in GaAlAs:Mn structures


  A self-consistent calculation of the electronic properties of GaAlAs:Mn
magnetic semiconductor quantum well structures is performed including the
Hartree term and the sp-d exchange interaction with the Mn magnetic moments.
The spin polarization density is obtained for several structure configurations.
Available experimental results are compared with theory.

</DOC>
<DOC>
<DOCNO> 120122 </DOCNO>
An ISOCAM Absorption Survey of the Structure of Pre-stellar Cloud Cores


  We present the results of a mid-infrared (7 micron) imaging survey of a
sample of 24 starless dense cores carried out at an angular resolution of 6
arcsec with the ISOCAM camera aboard the Infrared Space Observatory (ISO). The
targeted cores are believed to be pre-stellar in nature and to represent the
initial conditions of low-mass, isolated star formation. In previous
submillimeter dust continuum studies of such pre-stellar cores, it was found
that the derived column density profiles did not follow a single power-law such
as N[H2] \propto r^(-1) throughout their full extent but flattened out near
their center. These submillimeter observations however could not constrain the
density profiles at radii greater than ~ 10000 AU. The present absorption study
uses ISOCAM's sensitivity to map these pre-stellar cores in absorption against
the diffuse mid-infrared background. The goal was to determine their structure
at radii that extend beyond the limits of sensitivity of the submillimeter
continuum maps and at twiceas good an angular resolution. Among the 24 cores
observed in our survey, a majority of them show deep absorption features. The
starless cores studied here all show a column density profile that flattens in
the center, which confirms the submillimeter emission results. Moreover, beyond
a radius of ~ 5000-10000 AU, the typical column density profile steepens with
distance from core center and gets steeper than N[H2] \propto r^(-1), until it
eventually merges with the low-density ambient molecular cloud. At least three
of the cores present sharp edges at R ~ 15000-30000 AU and appear to be
decoupled from their parent clouds, providing finite reservoirs of mass for
subsequent star formation.

</DOC>
<DOC>
<DOCNO> 69219 </DOCNO>
Charge and Transition Form Factors of Light Mesons with Light-Front


  The charge and transition form factors of pion ($F_\pi$, $F_{\pi\gamma}$, and
$F_{\pi\gamma^*}$) are studied with the light-front quark model. We find that
our results for $F_\pi$ and $F_{\pi\gamma}$ agree very well with experimental
data. Furthermore, the decay constants of $\eta$ and $\eta'$ are evaluated. We
also calculate $F_{\eta\gamma}$ and $F_{\eta'\gamma}$ and compare with the
experimental data.

</DOC>
<DOC>
<DOCNO> 9491 </DOCNO>
Force-velocity relation and density profiles for biased diffusion in an


  In this paper, which completes our earlier short publication [Phys. Rev.
Lett. 84, 511 (2000)], we study dynamics of a hard-core tracer particle (TP)
performing a biased random walk in an adsorbed monolayer, composed of mobile
hard-core particles undergoing continuous exchanges with a vapor phase. In
terms of an approximate approach, based on the decoupling of the third-order
correlation functions, we obtain the density profiles of the monolayer
particles around the TP and derive the force-velocity relation, determining the
TP terminal velocity, V_{tr}, as the function of the magnitude of external bias
and other system's parameters. Asymptotic forms of the monolayer particles
density profiles at large separations from the TP, and behavior of V_{tr} in
the limit of small external bias are found explicitly.

</DOC>
<DOC>
<DOCNO> 13637 </DOCNO>
Dilute Bose gas: short-range particle correlations and ultraviolet


  The modified Bogoliubov model where the primordial interaction is replaced by
the t matrix is reinvestigated. It is shown to provide a negative value of the
kinetic energy for a strongly interacting dilute Bose gas, contrary to the
original Bogoliubov model. To clear up the origin of this failure, the correct
values of the kinetic and interaction energies of a dilute Bose gas are
calculated. It is demonstrated that both the problem of the negative kinetic
energy and the ultraviolet divergence, dating back to the well-known paper of
Lee, Yang and Huang, is connected with an inadequate picture of the short-range
boson correlations. These correlations are reconsidered within the
thermodynamically consistent model proposed earlier by the present authors.
Found results are in absolute agreement with the data of the Monte-Carlo
calculations for the hard-sphere Bose gas.

</DOC>
<DOC>
<DOCNO> 69622 </DOCNO>
New shapes of the rho-meson light-cone distribution amplitudes: how can


  We present new models of the rho-meson leading-twist light-cone distribution
amplitudes based on the QCD sum rule approach with nonlocal condensates. Their
shapes differ noticeably from that known in the literature. The
phenomenological consequences for physically important process B --> rho e nu
are discussed in the framework of the light-cone sum rules. The results are
compared with those found recently by P.Ball and V.M.Braun (1997).

</DOC>
<DOC>
<DOCNO> 119006 </DOCNO>
Stellar Populations and Galaxy Morphology at High Redshift


  In this article we investigate the morphology and stellar populations of
high-redshift galaxies through multi-waveband HST imaging and ground-based
spatially-resolved spectroscopy. We study the redshift evolution of galaxy
morphology in the Hubble Deep Field, using the deep IDT-NICMOS near-infrared
HST imaging coupled with spectroscopic and photometric redshifts. Using the
multi-waveband data to compare the appearance of galaxies at the same
rest-frame wavelengths reveals that "morphological k-corrections" (the change
in appearance when viewing high-z objects at shorter rest-frame wavelengths)
are only important in a minority of cases, and that galaxies were intrinsically
more peculiar at high redshift. One example of significant morphological
k-corrections is spiral galaxies, which often show more pronounced barred
structure in the near-infrared than in the optical. Therefore, the apparent
decline in the fraction of barred spirals at faint magnitudes in the optical
HDF may be due to band-shifting effects at the higher redshifts, rather than
intrinsic evolution. Using such features as the age-sensitive Balmer+4000Ang
break, the spatially- resolved colours of distant galaxies in
optical/near-infrared imaging can also be used to study their component stellar
populations. We supplement this with deep Keck/LRIS spectroscopy of two
extended sources: a chain galaxy at z=2.8 (HDF4-555.1, the "Hot Dog" - the
brightest U-drop Lyman-break galaxy in the HDF) and a pair of z=4.04
gravitationally lensed arcs behind the cluster Abell 2390. The absence of
measurable rotation across the z=2.8 chain galaxy implies that it is unikely to
be a disk viewed edge on. With the resolution enhancement from lensing, we
detect stellar populations of different ages in the z=4 arcs.

</DOC>
<DOC>
<DOCNO> 151000 </DOCNO>
Proposal for non-BPS D-brane action


  In this short note we would like to propose a form for the action of a
non-BPS D-brane, which will be manifestly supersymmetric invariant and
T-duality covariant. We also explicitly show that tachyon condensation on the
world-volume of this brane leads to the Dirac-Born-Infeld action for BPS
D(p-1)-brane.

</DOC>
<DOC>
<DOCNO> 39764 </DOCNO>
Measurements of Cross Sections and Forward-Backward Asymmetries at the Z


  We report on measurements of hadronic and leptonic cross sections and
leptonic forward-backward asymmetries performed with the L3 detector in the
years 1993-95. A total luminosity of 103 pb^-1 was collected at centre-of-mass
energies \sqrt{s} ~ m_Z and \sqrt{s} ~ m_Z +/- 1.8 GeV which corresponds to 2.5
million hadronic and 245 thousand leptonic events selected. These data lead to
a significantly improved determination of Z parameters. From the total cross
sections, combined with our measurements in 1990-92, we obtain the final
results: m_Z = 91189.8 +/- 3.1 MeV, Gamma_Z = 2502.4 +/- 4.2 MeV, Gamma_had =
1741.1 +/- 3.8 MeV, Gamma_l = 84.14 +/- 0.17 MeV. An invisible width of
Gamma_inv = 499.1 +/- 2.9 MeV is derived which in the Standard Model yields for
the number of light neutrino species N_nu = 2.978 +/- 0.014. Adding our results
on the leptonic forward-backward asymmetries and the tau polarisation, the
effective vector and axial-vector coupling constants of the neutral weak
current to charged leptons are determined to be \bar{g}_V^l = -0.0397 +/-
0.0017 and \bar{g}_A^l = -0.50153 +/- 0.00053.Including our measurements of the
Z -> b \bar{b} forward-backward and quark charge asymmetries a value for the
effective electroweak mixing angle of sin^2\bar{\theta}_W = 0.23093 +/- 0.00066
is derived. All these measurements are in good agreement with the Standard
Model of electroweak interactions. Using all our measurements of electroweak
observables an upper limit on the mass of the Standard Model Higgs boson of m_H
< 133 GeV is set at 95% confidence level.

</DOC>
<DOC>
<DOCNO> 67696 </DOCNO>
Thermal Abundances of Heavy Particles


  Matsumoto and Yoshimura [hep-ph/9910393] have argued that there are loop
corrections to the number density of heavy particles (in thermal equilibrium
with a gas of light particles) that are not Boltzmann suppressed by a factor of
e^(-M/T) at temperatures T well below the mass M of the heavy particle. We
argue, however, that their definition of the number density does not correspond
to a quantity that could be measured in a realistic experiment. We consider a
model where the heavy particles carry a conserved U(1) charge, and the light
particles do not. The fluctuations of the net charge in a given volume then
provide a measure of the total number of heavy particles in that same volume.
We show that these charge fluctuations are Boltzmann suppressed (to all orders
in perturbation theory). Therefore, we argue, the number density of heavy
particles is also Boltzmann suppressed.

</DOC>
<DOC>
<DOCNO> 11178 </DOCNO>
Spin dynamics and ordering of a cuprate stripe-antiferromagnet


  In La1.48Nd0.4Sr0.12CuO4 the 139La and 63Cu NQR relaxation rates and signal
wipe-out upon lowering temperature are shown to be due to purely magnetic
fluctuations. They follow the same renormalized classical behavior as seen in
neutron data, when the electronic spins order in stripes, with a small spread
in spin stiffness (15% spread in activation energy). The La signal, which
reappears at low temperatures, is magnetically broadened and experiences
additional wipe-out due to slowing down of the Nd fluctuations.

</DOC>
<DOC>
<DOCNO> 118755 </DOCNO>
Comments on the paper ``Polarimetric Constraints on the Optical


  GRB 990123 is the most luminous event detected so far, and in an important
paper, Hjorth et al. (1999) reported an upper limit on the degree of linear
polarization of the optical afterglow for this burst (P <2.3%). One of the
interprtations for this small value of P was that the emission was probably due
a relativistic jet with ordered magnetic field, and the viewing angle in the
lab frame theta' <= Gamma^{-1}, where Gamma is the bulk Lorentz factor of the
jet at the time of the optical emission. We point out that this conclusion
resulted from a confusion between the angles measured in the lab frame and in
the plasma rest frame. For ordered magnetic field, one would actually obtain a
large value of P because the above mentioned angle would correspond to a very
large angle, theta <= \pi/2, in the plasma rest frame. And this is probably the
case with the blazars. On the other hand, it is indeed possible to have P ~ 0
if the magnetic field of GRB 990123 was completely chaotic and the viewing
angle was considerably smaller than the semi-angle of the jet.

</DOC>
<DOC>
<DOCNO> 69942 </DOCNO>
Bounds on Bosonic Topcolor


  We consider the phenomenology of models in which electroweak symmetry
breaking is triggered by new strong dynamics affecting the third generation and
is transmitted to the light fermions via a fundamental Higgs doublet. While
similar in spirit to the old bosonic technicolor idea, such `bosonic topcolor'
models are allowed by current phenomenological constraints, and may arise
naturally in models with large extra dimensions. We study the parameter space
of a minimal low-energy theory, including bounds from Higgs boson searches,
precision electroweak parameters, and flavor changing neutral current
processes. We show that the model can provide a contribution to D0-D0-bar
mixing as large as the current experimental bound.

</DOC>
<DOC>
<DOCNO> 12502 </DOCNO>
Kondo ground state in a quantum dot with an even number of electrons


  Kondo conduction has been observed in a quantum dot with an even number of
electrons at the Triplet-Singlet degeneracy point produced by applying a small
magnetic field $B$ orthogonal to the dot plane.
  At a much larger field $ B \sim B_*$, orbital effects induce the reversed
transition from the Singlet to the Triplet state. We study the newly proposed
Kondo behavior at this point. Here the Zeeman spin splitting cannot be
neglected, what changes the nature of the Kondo coupling. On grounds of exact
diagonalization results in a dot with cylindrical symmetry, we show that, at
odds with what happens at the other crossing point, close to $B_*$, orbital and
spin degrees of freedom are ``locked together'', so that the Kondo coupling
involves a fictitious spin 1/2 only, which is fully compensated by conduction
electrons under suitable conditions. In this sense, spin at the dot is
fractionalized. We derive the scaling equation of the system by means of a
nonperturbative variational approach. The approach is extended to the $B \neq
B_*$-case and the residual magnetization on the dot is discussed.

</DOC>
<DOC>
<DOCNO> 119420 </DOCNO>
Sgr A* Polarization: No ADAF, Low Accretion Rate, and Non-Thermal


  The recent detection of polarized radiation from Sgr A* requires a
non-thermal electron distribution for the emitting plasma. The Faraday rotation
measure must be small, placing strong limits on the density and magnetic field
strength. We show that these constraints rule out advection-dominated accretion
flow models. We construct a simple two-component model which can reproduce both
the radio to mm spectrum and the polarization. This model predicts that the
polarization should rise to nearly 100% at shorter wavelengths. The first
component, possibly a black-hole powered jet, is compact, low density, and
self-absorbed near 1 mm with ordered magnetic field, relativistic Alfven speed,
and a non-thermal electron distribution. The second component is poorly
constrained, but may be a convection-dominated accretion flow with dM/dt~10^-9
M_Sun/yr, in which feedback from accretion onto the black hole suppresses the
accretion rate at large radii. The black hole shadow should be detectable with
sub-mm VLBI.

</DOC>
<DOC>
<DOCNO> 121091 </DOCNO>
A Wide-Field CCD Survey for Centaurs and Kuiper Belt Objects


  A modified Baker-Nunn camera was used to conduct a wide-field survey of 1428
square degrees of sky near the ecliptic in search of bright Kuiper Belt objects
and Centaurs. This area is an order of magnitude larger than any previously
published CCD survey for Centaurs and Kuiper Belt Objects. No new objects
brighter than red magnitude m=18.8 and moving at a rate 1"/hr to 20"/hr were
discovered, although one previously discovered Centaur 1997 CU26 Chariklo was
serendipitously detected. The parameters of the survey were characterized using
both visual and automated techniques. From this survey the empirical projected
surface density of Centaurs was found to be SigmaCentaur(m<18.8)=7.8(+16.0
-6.6)x10^-4 per square degree and we found a projected surface density 3sigma
upper confidence limit for Kuiper Belt objects of SigmaKBO(m< 18.8)<4.1x10^-3
per square degree. We discuss the current state of the cumulative luminosity
functions of both Centaurs and Kuiper Belt objects. Through a Monte Carlo
simulation we show that the size distribution of Centaurs is consistent with a
q=4 differential power law, similar to the size distribution of the parent
Kuiper Belt Objects. The Centaur population is of order 10^7 (radius > 1 km)
assuming a geometric albedo of 0.04. About 100 Centaurs are larger than 50 km
in radius, of which only 4 are presently known. The current total mass of the
Centaurs is 10^-4 Earth Masses. No dust clouds were detected resulting from
Kuiper Belt object collisions, placing a 3sigma upper limit <600 collisionally
produced clouds of m<18.8 per year.

</DOC>
<DOC>
<DOCNO> 117647 </DOCNO>
Properties of Gamma-Ray Burst Classes


  The three gamma-ray burst (GRB) classes identified by statistical clustering
analysis (Mukherjee et al. 1998) are examined using the pattern recognition
algorithm C4.5 (Quinlan 1986). Although the statistical existence of Class 3
(intermediate duration, intermediate fluence, soft) is supported, the
properties of this class do not need to arise from a distinct source
population. Class 3 properties can easily be produced from Class 1 (long, high
fluence, intermediate hardness) by a combination of measurement error,
hardness/intensity correlation, and a newly-identified BATSE bias (the fluence
duration bias). Class 2 (short, low fluence, hard) does not appear to be
related to Class 1.

</DOC>
<DOC>
<DOCNO> 121063 </DOCNO>
Explorations in Hubble Space: A Quantitative Tuning Fork


  In order to establish an objective framework for studying galaxy morphology,
we have developed a quantitative two-parameter description of galactic
structure that maps closely on to Hubble's original tuning fork. Any galaxy can
be placed in this "Hubble space", where the x-coordinate measures position
along the early-to-late sequence, while the y-coordinate measures in a
quantitative way the degree to which the galaxy is barred. The parameters
defining Hubble space are sufficiently robust to allow the formation of
Hubble's tuning fork to be mapped out to high redshifts. In the present paper,
we describe a preliminary investigation of the distribution of local galaxies
in Hubble space, based on the CCD imaging atlas of Frei et al. (1996). We find
that barred, weakly-barred, and unbarred galaxies are remarkably well-separated
on this diagnostic diagram. The spiral sequence is clearly bimodal and indeed
approximates a tuning fork: strongly-barred and unbarred spirals do not simply
constitute the extrema of a smooth unimodal distribution of bar strength, but
rather populate two parallel sequences. Strongly barred galaxies lie on a
remarkably tight sequence, strongly suggesting the presence of an underlying
unifying physical process. Rather surprisingly, weakly barred systems do not
seem to correspond to objects bridging the parameter space between unbarred and
strongly barred galaxies, but instead form an extension of the regular spiral
sequence. This relation lends support to models in which the bulges of
late-type spirals originate from secular processes driven by bars.

</DOC>
<DOC>
<DOCNO> 71449 </DOCNO>
Neutron EDM from Electric and Chromoelectric Dipole Moments of Quarks


  Using QCD sum rules, we calculate the electric dipole moment of the neutron
d_n induced by all CP violating operators up to dimension five. We find that
the chromoelectric dipole moments of quarks \tilde d_i, including that of the
strange quark, provide significant contributions comparable in magnitude to
those induced by the quark electric dipole moments d_i. When the theta term is
removed via the Peccei-Quinn symmetry, the strange quark contribution is also
suppressed and d_n =(1\pm 0.5)[0.55e(\tilde d_d + 0.5\tilde
d_u)+0.7(d_d-0.25d_u)].

</DOC>
<DOC>
<DOCNO> 179036 </DOCNO>
Polarization observables in elastic electron deuteron scattering


  The general formalism for polarization observables in elastic electron
deuteron scattering is extended to incorporate parity and time reversal
violating contributions. Parity violating effects arise from the interference
of $\gamma$ and $Z$ exchange as well as from the hadronic sector via a small
parity violating component in the deuteron. In addition we have allowed for
time reversal invariance violating contributions in the hadronic sector. Formal
expressions for the additional structure functions are derived, and their
decomposition into the various multipole contributions are given explicitly.

</DOC>
<DOC>
<DOCNO> 8739 </DOCNO>
Electronic and Structural Properties of Carbon Nano-Horns


  We use parametrized linear combination of atomic orbitals calculations to
determine the stability, optimum geometry and electronic properties of
nanometer-sized capped graphitic cones, called ``nano-horns''. Different
nano-horn morphologies are considered, which differ in the relative location of
the five terminating pentagons. Simulated scanning tunneling microscopy images
of the various structures at different bias voltages reflect a net electron
transfer towards the pentagon vertex sites. We find that the local density of
states at the tip, observable by scanning tunneling spectroscopy, can be used
to discriminate between different tip structures. Our molecular dynamics
simulations indicate that disintegration of nano-horns at high temperatures
starts in the highest-strain region near the tip.

</DOC>
<DOC>
<DOCNO> 9362 </DOCNO>
Disorder and interactions in quantum Hall ferromagnets near $\nu=1$


  We report on a finite-size Hartree-Fock study of the competition between
disorder and interactions in a two-dimensional electron gas near Landau level
filling factor $\nu=1$. The ground state at $\nu=1$ evolves with increasing
disorder from a fully spin-polarized ferromagnet with a charge gap, to a
partially spin-polarized ferromagnetic Anderson insulator, to a quasi-metallic
paramagnet at the critical point between $i=0$ and $i=2$ quantum Hall plateaus.
Away from $\nu=1$, the ground state evolves from a ferromagnetic Skyrmion
quasiparticle glass, to a conventional quasiparticle glass, and finally to a
conventional Anderson insulator. We comment on signatures of these different
regimes in low-temperature transport and NMR lineshape and peak position data.

</DOC>
<DOC>
<DOCNO> 11614 </DOCNO>
Saddles on the potential energy landscape of a Lennard-Jones liquid


  By means of molecular dynamics simulations, we study the stationary points of
the potential energy in a Lennard-Jones liquid, giving a purely geometric
characterization of the energy landscape of the system. We find a linear
relation between the degree of instability of the stationary points and their
potential energy, and we locate the energy where the instability vanishes. This
threshold energy marks the border between saddle-dominated and minima-dominated
regions of the energy landscape. The temperature where the potential energy of
the Stillinger-Weber minima becomes equal to the threshold energy turns out to
be very close to the mode-coupling transition temperature.

</DOC>
<DOC>
<DOCNO> 14144 </DOCNO>
Cluster Spin Glass Distribution Functions in La$_{2-x}$Sr$_x$CuO$_4$


  Signatures of the cluster spin glass have been found in a variety of
experiments, with an effective onset temperature $T_{on}$ that is frequency
dependent. We reanalyze the experimental results and find that they are
characterized by a distribution of activation energies, with a nonzero glass
transition temperature $T_g(x)<T_{on}$. While the distribution of activation
energies is the same, the distribution of weights depends on the process.
Remarkably, the weights are essentially doping independent.

</DOC>
<DOC>
<DOCNO> 69766 </DOCNO>
Final state interaction and $B\to KK$ decays in perturbative QCD


  We predict branching ratios and CP asymmetries of the $B\to KK$ decays using
perturbative QCD factorization theorem, in which tree, penguin, and
annihilation contributions, including both factorizable and nonfactorizable
ones, are expressed as convolutions of hard six-quark amplitudes with universal
meson wave functions. The unitarity angle $\phi_3= 90^o$ and the $B$ and $K$
meson wave functions extracted from experimental data of the $B\to K\pi$ and
$\pi\pi$ decays are employed. Since the $B\to KK$ decays are sensitive to
final-state-interaction effects, the comparision of our predictions with future
data can test the neglect of these effects in the above formalism. The CP
asymmetry in the $B^\pm\to K^\pm K^0$ modes and the $B_d^0\to K^\pm K^\mp$
branching ratios depend on annihilation and nonfactorizable amplitudes. The
$B\to KK$ data can also verify the evaluation of these contributions.

</DOC>
<DOC>
<DOCNO> 151647 </DOCNO>
Electric-Magnetic Duality in IIB Matrix Model with D-brane


  We consider electric-magnetic duality(S-duality) in IIB matrix model with a
D3-brane background. We propose the duality transformation by considering that
of noncommutative Yang-Mills theory(NCYM) in four dimension. NCYM derived from
the matrix model has a Yang-Mills coupling related to the noncommutativity of
the spacetime. We argue that open strings bits as bi-local fields on the
spacetime are decoupled from the bulk in NCOS decoupling limits as it is in
string theory approach. We also discuss how our four dimensional spacetime
relates to higher, by applying the decoupling and the commutative limits of the
backgrounds of the matrix model.

</DOC>
<DOC>
<DOCNO> 100028 </DOCNO>
On the functoriality of Lott's secondary analytic index


  We verify that the formula of X. Ma for the analytic torsion form of an
iterated fibration implies that Lott's secondary analytic index is functorial.

</DOC>
<DOC>
<DOCNO> 69082 </DOCNO>
Dynamics of Cosmic Necklaces


  We perform numerical simulations of cosmic necklaces (systems of monopoles
connected to two strings each) and investigate the conditions under which
monopoles annihilate. When the total monopole energy is large compared to the
string energy, we find that the string motion is no longer periodic, and thus
the strings will be chopped up by self intersection. When the total monopole
energy is much smaller than the string energy, the string motion is periodic,
but that of the monopoles is not, and thus the monopoles travel along the
string and annihilate with each other.

</DOC>
<DOC>
<DOCNO> 70138 </DOCNO>
Chiral Condensates in the Light-Cone Vacuum


  In light-cone quantization, the standard procedure to characterize the phases
of a system by appropriate ground state expectation values fails. The
light-cone vacuum is determined kinematically. We show that meaningful
quantities which can serve as order parameters are obtained as expectation
values of Heisenberg operators in the equal (light-cone) time limit. These
quantities differ from the purely kinematical expectation values of the
corresponding Schroedinger operators. For the Nambu--Jona-Lasinio and the
Gross-Neveu model, we describe the spontaneous breakdown of chiral symmetry; we
derive within light-cone quantization the corresponding gap equations and the
values of the chiral condensate.

</DOC>
<DOC>
<DOCNO> 10805 </DOCNO>
Discrimination between the superconducting gap and the pseudo-gap in


  Intrinsic tunneling spectroscopy in high magnetic field ($H$) is used for a
direct test of superconducting features in a quasiparticle density of states of
high-$T_c$ superconductors. We were able to distinguish with a great clarity
two co-existing gaps: (i) the superconducting gap, which closes as $H \to
H_{c2}(T)$ and $T\to T_c(H)$, and (ii) the $c$-axis pseudo-gap, which does not
change neither with $H$, nor $T$. Strikingly different magnetic field
dependencies, together with previously observed different temperature
dependencies of the two gaps ~\cite{Krasnov}, speak against the superconducting
origin of the pseudo-gap.

</DOC>
<DOC>
<DOCNO> 121404 </DOCNO>
Lensing properties of 7 damped Lyman-alpha absorbing galaxy-QSO pairs


  Le Brun et al. (1997) presented the first identifications of the galaxies
giving rise to 7 intermediate redshift damped Ly-alpha (DLA) absorption
systems. Here, we study the gravitational lensing properties of these
foreground galaxies based on their observed optical appearance and on the
absence of any secondary lensed quasar image. We consider the possibility that
any secondary image be hidden due to extinction by dust, but find it unlikely.
We derive upper limits on the amplification factor affecting the luminosity of
the background quasars; in each case, this factor is found to be less than 0.3
mag. We also obtain upper limits on the total mass of the damped Ly-alpha
galaxies, within radii equal to the quasar impact parameters. Mass-to-light
ratios are found to be consistent with existing estimates based on X-ray
emission or on motion of dwarf satellites. Although we show that lensing is not
important in this sample, we note that existing DLA surveys used to determine
the cosmological density of gas at z<1 are based on samples of quasars brighter
than the ones considered here and for which the amplification bias is likely to
be stronger.

</DOC>
<DOC>
<DOCNO> 179041 </DOCNO>
Non-localities and Fermi motion corrections in $K^-$ atoms


  We evaluate the p-wave $K^-N$ amplitudes from the chiral Lagrangians and from
there construct the p-wave part of the $K^-$ nucleus optical potential plus a
small s-wave part induced from the elementary p-wave amplitude and the nuclear
Fermi motion. Simultaneously, the momentum and energy dependence of the s-wave
optical potential, previously developed, are taken into account and shown to
generate a small p-wave correction to the optical potential. All the
corrections considered are small compared to the leading s-wave potential, and
lead to changes in the shifts and widths which are smaller than the
experimental errors.
  A thorough study of the threshold region and low densities is conducted,
revealing mathematical problems for which a physical solution is given.

</DOC>
<DOC>
<DOCNO> 119973 </DOCNO>
Can Rotational Properties of General Relativistic Compact Objects Be


  We propose an approximate description of basic parameters (radius, mass and
oblateness) of general relativistic compact rotating objects in terms of the
parameters of the static configuration and of the angular velocity only. The
representation in terms of static properties is derived using the condition of
stationary equilibrium together with some phenomenological assumptions. The
predicted radius and mass of rotating neutron star (described by some realistic
equations of state) and strange star (described by the bag model equation of
state) are compared with data obtained by numerical integration of
gravitational field equation. The obtained formulae also allow a simple
derivation of the "empirical" equation relating the maximum rotation frequency
$\Omega_{max}$ of uniformly rotating star models to the mass and radius of the
maximum allowable mass configuration of the non-rotating model.

</DOC>
<DOC>
<DOCNO> 121793 </DOCNO>
Galaxy Modelling - II. Multi-Wavelength Faint Counts from a


  (Abridged) This paper predicts self-consistent faint galaxy counts from the
UV to the submm wavelength range. The STARDUST spectral energy distributions
described in Devriendt et al. (1999) are embedded within the explicit
cosmological framework of a simple semi-analytic model of galaxy formation and
evolution. We build a class of models which capture the luminosity budget of
the universe through faint galaxy counts and redshift distributions in the
whole wavelength range spanned by our spectra. In contrast with a rather stable
behaviour in the optical and even in the far-IR, the submm counts are
dramatically sensitive to variations in the cosmological parameters and changes
in the star formation history. Faint submm counts are more easily accommodated
within an open universe with a low value of $\Omega_0$, or a flat universe with
a non-zero cosmological constant. This study illustrates the implementation of
multi-wavelength spectra into a semi-analytic model. In spite of its
simplicity, it already provides fair fits of the current data of faint counts,
and a physically motivated way of interpolating and extrapolating these data to
other wavelengths and fainter flux levels.

</DOC>
<DOC>
<DOCNO> 68596 </DOCNO>
Poisson sigma models and symplectic groupoids


  We consider the Poisson sigma model associated to a Poisson manifold. The
perturbative quantization of this model yields the Kontsevich star product
formula. We study here the classical model in the Hamiltonian formalism. The
phase space is the space of leaves of a Hamiltonian foliation and has a natural
groupoid structure. If it is a manifold then it is a symplectic groupoid for
the given Poisson manifold. We study various families of examples. In
particular, a global symplectic groupoid for a general class of two-dimensional
Poisson domains is constructed.

</DOC>
<DOC>
<DOCNO> 80697 </DOCNO>
A High Precision Study of the QQ(bar) Potential from Wilson Loops in the


  For lattice QCD with two sea quark flavours we compute the static quark
antiquark potential V(R) in the regime where string breaking is expected. In
order to increase statistics, we make full use of the lattice information by
including all lattice vectors R to any possible lattice separation in the
infrared regime. The corresponding paths between the lattice points are
constructed by means of a generalized Bresenham algorithm as known from
computer graphics. As a results we achieve a determination of the unquenched
potential in the range .8 to 1.5 fm with hitherto unknown precision.
Furthermore, we demonstrate some error reducing methods for the evaluation of
the transition matrix element between two- and four-quark states.

</DOC>
<DOC>
<DOCNO> 102806 </DOCNO>
It is consistent with ZFC that B_1-groups are not B_2-groups


  A torsion-free abelian group B of arbitrary rank is called a B_1-group if
Bext^1(B,T)=0 for every torsion abelian group T, where Bext^1 denotes the group
of equivalence classes of all balanced exact extensions of T by B. It is a
long-standing problem whether or not the class of B_1-groups coincides with the
class of B_2-groups. A torsion-free abelian group B is called a B_2-group if
there exists a continuous well-ordered ascending chain of pure subgroups,
  0=B_0 subset B_1 subset ... subset B_alpha subset ... subset B_lambda
=B=bigcup_{alpha in lambda} B_alpha such that B_{alpha+1}=B_alpha+G_alpha for
every alpha in lambda for some finite rank Butler group G_alpha. Both,
B_1-groups and B_2-groups are natural generalizations of finite rank Butler
groups to the infinite rank case and it is known that every B_2-group is a
B_1-group. Moreover, assuming V=L it was proven that the two classes coincide.
Here we demonstrate that it is undecidable in ZFC whether or not all B_1-groups
are B_2-groups. Using Cohen forcing we prove that there is a model of ZFC in
which there exists a B_1-group that is not a B_2-group.

</DOC>
<DOC>
<DOCNO> 178604 </DOCNO>
Algebraic Model for Quantum Scattering. Reformulation, Analysis and


  The convergence problem for scattering states is studied in detail within the
framework of the Algebraic Model, a representation of the Schrodinger equation
in an L^2 basis. The dynamical equations of this model are reformulated
featuring new "Dynamical Coefficients", which explicitly reveal the potential
effects. A general analysis of the Dynamical Coefficients leads to an optimal
basis yielding well converging, precise and stable results. A set of strategies
for solving the equations for non-optimal bases is formulated based on the
asymptotic behaviour of the Dynamical Coefficients. These strategies are shown
to provide a dramatically improved convergence of the solutions.

</DOC>
<DOC>
<DOCNO> 11040 </DOCNO>
Superconductivity and Ferromagnetism from Effective Mass Reduction


  Within a simple model Hamiltonian, both superconductivity and metallic
ferromagnetism can be understood as arising from lowering of kinetic energy as
the ordered state develops, due to a reduction in the carriers effective mass,
or equivalently, a bandwidth expansion. Experimental manifestation of this
physics has been detected in both high Tc superconductors and large
magnetoresistance ferromagnets, as an anomalous transfer of spectral weight in
optical absorption from high to low frequencies as the ordered state develops.
It is proposed that this general principle is common to the essential physics
of superconductivity and ferromagnetism in nature, and hence that these effects
in optical properties, although often smaller in magnitude, should exist in all
superconductors and metallic ferromagnets.

</DOC>
<DOC>
<DOCNO> 101151 </DOCNO>
Elliptic Genera of singular varieties, orbifold elliptic genus and


  This paper surveys the authors recent work on two variable elliptic genus of
singular varieties. The last section calculates a generating function for the
elliptic genera of symmetric products. This generalizes the classical results
of Macdonald and Zagier.

</DOC>
<DOC>
<DOCNO> 99557 </DOCNO>
Twist deformations for Yangians


  It is demonstrated how chains of twists for classical Lie algebras induce the
new twist deformations (the deformed Yangians) that quantize the generalized
rational solutions of the classical Yang-Baxter equation. For the case of Y(g)
with g=so(2N+1) the explicit expression for the corresponding R-matrix is given
in the defining representation.

</DOC>
<DOC>
<DOCNO> 70924 </DOCNO>
Neutrino Reactions on Deuteron


  The cross sections for the \nu-d and \bar{\nu}-d reactions are calculated for
the incident energy up to E_\nu = 170 MeV, with the use of a phenomenological
Lagrangian approach. We assess and improve the reliability of the employed
calculational method by examining the dependence of the results on various
input and approximations that go into the calculation. The main points of
improvements over the existing work are: (1) use of the "modern" NN potentials;
(2) use of the more accurate nucleon weak-interaction form factors; (3)
monitoring the strength of a vertex that governs the exchange-current
contribution, with the use of data on the related process, n+p\to d+\gamma. In
addition to the total cross sections, we present various differential cross
sections that are expected to be useful for the SNO and other experiments. In
the low energy regime relevant to the solar neutrinos, the newly calculated
total cross sections agree with the existing literature values. The origins of
slight differences found for higher energies are discussed. The ratio between
the neutral-current and charged-current reaction cross sections is found to be
extremely stable against any variations in the input of our calculation.

</DOC>
<DOC>
<DOCNO> 9104 </DOCNO>
Pseudospin Anisotropy Classification of Quantum Hall Ferromagnets


  Broken symmetry ground states with uniform electron density are common in
quantum Hall systems when two Landau levels simultaneously approach the
chemical potential at integer filling factor $\nu$. The close analogy between
these two-dimensional electron system states and conventional itinerant
electron ferromagnets can be emphasized by using a pseudospin label to
distinguish the two Landau levels. As in conventional ferromagnets, the
evolution of the system's state as external field parameters are varied is
expected to be sensitive to the dependence of ground state energy on pseudospin
orientation. We discuss the predictions of Hartree-Fock theory for the
dependence of the sign and magnitude of the pseudospin anisotropy energy on the
nature of the crossing Landau levels. We build up a classification scheme for
quantum Hall ferromagnets that applies for single layer and bilayer systems
with two aligned Landau levels distinguished by any combination of real-spin,
orbit-radius, or growth direction degree-of-freedom quantum numbers. The
possibility of in-situ tuning between easy-axis and easy-plane quantum Hall
ferromagnets is discussed for biased bilayer systems with total filling factors
$\nu=3$ or $\nu=4$. Detailed predictions are made for the bias dependence of
pseudospin reversal properties in $\nu=3$ bilayer systems.

</DOC>
<DOC>
<DOCNO> 99684 </DOCNO>
Hereditary indecomposability and the Intermediate Value Theorem


  We show that hereditarily indecomposable spaces can be characterized by a
special instance of the Intermediate Value Theorem in their rings of continuous
functions.

</DOC>
<DOC>
<DOCNO> 7691 </DOCNO>
Irreversibility temperature from magnetic relaxation


  Simulation of the magnetic relaxation in a model of hard superconductor
reveals a new time scale below the irreversibility temperature. The relaxation
in this new time scale, which appears in an intermediate time window, is a
power law and is related to self organization of the magnetic flux around the
critical current density J_c during the relaxation. Emergence of a new time
scale which along with the time scale for long time relaxation due to thermally
activated process dynamically identifies the irreversibility temperature.

</DOC>
<DOC>
<DOCNO> 121483 </DOCNO>
Compact High Velocity Clouds


  We summarize the observed properties of the CHVC population, which provide
strong evidence for source distances in the range 200-1000 kpc. At these
distances, the population corresponds to strongly dark-matter dominated
sub-dwarf galaxies still accreting onto the more massive Local Group systems.
Recent searches for faint associated stellar populations have revealed
red-giant candidates for which follow-up spectroscopy is scheduled. A sensitive
HI survey for CHVC counterparts in the NGC 628 galaxy group has allowed
tentative detection of 40 candidates, for which confirming observations have
been approved. Many open issues should be resolved by observational programs
within the coming years.

</DOC>
<DOC>
<DOCNO> 69350 </DOCNO>
From CKM Matrix to MNS Matrix: A Model Based on Supersymmetric $SO(10)


  We construct a realistic model based on SUSY SO(10) with U(2) flavor
symmetry. In contrast to the commonly used effective operator approach,
$126-$dimensional Higgses are used to construct the Yukawa sector. R-parity
symmetry is thus preserved at low energies. The Dirac and right-handed Majorana
mass matrices in our model have very small mixing, and they combine with the
seesaw mechanism resulting in a large leptonic mixing. The symmetric mass
textures arising from the left-right symmetry breaking chain of SO(10) give
rise to very good predictions; 15 masses (including 3 right-handed Majorana
neutrino masses) and 6 mixing angles are predicted by 11 parameters. Both the
vacuum oscillation and LOW solutions are favored for the solar neutrino
problem.

</DOC>
<DOC>
<DOCNO> 178514 </DOCNO>
Ground-$\gamma$ band coupling in heavy deformed nuclei and SU(3)


  We derive analytic expressions for the energies and $B(E2)$-transition
probabilities in the states of the ground and $\gamma$ bands of heavy deformed
nuclei within a collective Vector-Boson Model with SU(3) dynamical symmetry. On
this basis we examine the analytic behavior of the SU(3) energy splitting and
the B(E2) interband transition ratios in the SU(3) contraction limits of the
model. The theoretical analyses outline physically reasonable ways in which the
ground-$\gamma$ band coupling vanishes. The experimental data on the lowest
collective states of even-even rare earth nuclei and actinides strongly support
the theoretical results. They suggest that a transition from the
ground-$\gamma$ band coupling scheme to a scheme in which the ground band is
situated in a separate irreducible representation of SU(3) should be realized
towards the midshell regions. We propose that generally the SU(3) group
contraction process should play an important role for such a kind of
transitions in any collective band coupling scheme in heavy deformed nuclei.

</DOC>
<DOC>
<DOCNO> 102638 </DOCNO>
On Fourier orthogonal projections in the rotation algebra


  Projections are constructed in the rotation algebra that are orthogonal to
their Fourier transform and which are fixed under the flip automorphism. Such
projections are expected in a construction of an inductive limit structure for
the irrational rotation algebra that is invariant under the Fourier transform.
(Namely, as two circle algebras of the same dimension, that are swapped by the
Fourier transform, plus a few points.) The calculation is based on Rieffel's
construction of the Schwartz space as an equivalence bimodule of rotation
algebras as well as on the theory of Theta functions.

</DOC>
<DOC>
<DOCNO> 121152 </DOCNO>
Changing Molecular Gas Properties in the Bar and Canter of NGC7479


  We present sensitive interferometric 12CO, 13CO and HCN observations of the
barred spiral galaxy NGC7479, known to be one of the few barred galaxies with a
continuous gas-filled bar. We focus on the investigation and interpretation of
12CO/13CO line intensity ratios, which is facilitated by having more than 90%
of the flux in our interferometer maps. The global (9kpc by 2.5kpc) value of
the 12CO/13CO ratio is high at 20 - 40. On smaller scales (~ 750 pc), the ratio
is found to vary dramatically, reaching values > 30 in large parts of the bar,
but dropping to values ~ 5, typical for galactic disks, at a 13CO condensation
in the southern part of the bar. We interpret these changes in terms of the
relative importance of the contribution of a diffuse molecular component,
characterized by unbound gas that has a moderate optical depth in the 12CO(1 -
0) transition. This component dominates the 12CO along the bar and is also
likely to play an important role in the center of NGC7479. In the center, the
12CO and the HCN intensity peaks coincide, while the 13CO peak is slightly
offset. This can be explained in terms of high gas temperature and density at
the 12CO peak position. Along the bar, the relation between the distribution of
12CO, 13CO, dust lanes and velocity gradient is complex. A southern 13CO
condensation is found offset from the 12CO ridge that generally coincides with
the most prominent dust lanes. It is possible that strong 13CO detections along
the bar indicate quiescent conditions, downstream from the major bar shock.
Still, these condensations are found close to high velocity gradients. In the
central region, the velocity gradient is traced much more closely by 13CO than
by 12CO.

</DOC>
<DOC>
<DOCNO> 151866 </DOCNO>
Dynamics of Wilson Observables in Non-Commutative Gauge Theory


  An equation for the quantum average of the gauge invariant Wilson loop in
non-commutative Yang-Mills theory with gauge group U(N) is obtained. In the 't
Hooft limit, the equation reduces to the loop equation of ordinary Yang-Mills
theory. At finite $N$, the equation involves the quantum averages of the
additional gauge invariant observables of the non-commutative theory associated
with open contours in space-time. We also derive equations for correlators of
several gauge invariant (open or closed) Wilson lines. Finally, we discuss a
perturbative check of our results.

</DOC>
<DOC>
<DOCNO> 102285 </DOCNO>
Fu/v cik Spectrum for the Neumann Problem with Indefinite Weights


  We obtain a description of the Fu\v{c}ik spectrum associated to the
one-dimensional asymmetric problem with indefinite weights $Lu = am(t)u^+ -
bn(t)u^-$ in $]T_1, T_2[$, $u'(T_1) = 0 = u'(T_2)$, where $L$ is a
Sturm-Liouville operator. Our approach is based on the shooting method.

</DOC>
<DOC>
<DOCNO> 122893 </DOCNO>
3D MHD Simulations of Radio Galaxies Including Nonthermal Electron


  We report on an effort to study the connections between dynamics in simulated
radio galaxy plasma flows and the properties of nonthermal electron populations
carried in those flows. To do this we have introduced a new numerical scheme
for electron transport that allows a much more detailed look at this problem
than has been possible before. Especially when the dynamics is fully three
dimensional the flows are generally chaotic in the cocoon, and the jet itself
can flail about violently. The bending jet can pinch itself off and redirect
itself to enhance its penetration of the ambient medium. These behaviors often
eliminate the presence of a strong jet termination shock, which is assumed
present in all modern cartoon models of the RG phenomenon. Instead a much more
complex ``shock web'' forms near the end of the jet that leads to a far less
predictable pattern of particle acceleration. Similarly, the magnetic fields in
these flows are highly filamented, as well as spatially and temporally
intermittent. This leads to a very localized and complex pattern of synchrotron
aging for relativistic electron populations, which makes it difficult to use
properties of the electron spectrum to infer the local rate of aging.

</DOC>
<DOC>
<DOCNO> 70841 </DOCNO>
Cosmic anti-friction and accelerated expansion


  We explain an accelerated expansion of the present universe, suggested from
observations of supernovae of type Ia at high redshift, by introducing an
anti-frictional force that is self-consistently exerted on the particles of the
cosmic substratum. Cosmic anti-friction, which is intimately related to
``particle production'', is shown to give rise to an effective negative
pressure of the cosmic medium. While other explanations for an accelerated
expansion (cosmological constant, quintessence) introduce a component of dark
energy besides ``standard'' cold dark matter (CDM) we resort to a
phenomenological one-component model of CDM with internal self-interactions. We
demonstrate how the dynamics of the LambdaCDM model may be recovered as a
special case of cosmic anti-friction. We discuss the connection with
two-component models and obtain an attractor behavior for the ratio of the
energy densities of both components which provides a possible phenomenological
solution to the coincidence problem.

</DOC>
<DOC>
<DOCNO> 120402 </DOCNO>
HST imaging survey of sub-mJy star-forming galaxies I: morphologies at z


  We present the first results of our HST WFPC2 F814W snapshot imaging survey,
targeting virtually all sub-mJy decimetric radio-selected star-forming
galaxies. The radio selection at ~1 GHz is free from extinction effects and the
radio luminosities are largely unaffected by AGN contamination, making these
galaxies ideal tracers of the cosmic star formation history. A sub-sample of 4
targets is presented here, selected at 1.4 GHz from the spectroscopically
homogenous and complete samples of Benn et al. (1993) and Hopkins et al.
(1999). The redshifts are confined to a narrow range around z~0.2, to avoid
differential evolution, with a radio luminosity close to L* where the galaxies
dominate the comoving volume-averaged star formation rate. We find clearly
disturbed morphologies resembling those of ultraluminous infrared galaxies,
indicating that galaxy interactions may be the dominant mechanism for
triggering star formation at these epochs. The morphologies are also clearly
different from coeval quasars and radiogalaxies, as found in star-forming
galaxies selected at other wavelengths. This may prove challenging for models
which propose direct causal links between AGN evolution and the cosmic star
formation history at these epochs. The asymmetries are typically much larger
than seen in the CFRS at similar redshifts, optical luminosities and
Halpha-derived star formation rates, indicating the possible existence of an
obscuration-related morphological bias in such samples.

</DOC>
<DOC>
<DOCNO> 122431 </DOCNO>
Metallicity estimates for A-, F-, and G-type stars from the


  The Edinburgh-Cape Blue Object Survey is an ongoing project to identify and
analyse a large sample of hot stars selected initially on the basis of
photographic colours (down to a magnitude limit B~18.0) over the entire
high-Galactic-latitude southern sky, then studied with broadband UBV photometry
and medium-resolution spectroscopy. Due to unavoidable errors in the initial
candidate selection, stars that are likely metal-deficient dwarfs and giants of
the halo and thick-disk populations are inadvertently included, yet are of
interest in their own right. In this paper we discuss a total of 206 candidate
metal-deficient dwarfs, subgiants, giants, and horizontal-branch stars with
photoelectric colours redder than (B-V)o = 0.3, and with available
spectroscopy. Radial velocities, accurate to ~10-15 km/s, are presented for all
of these stars. Spectroscopic metallicity estimates for these stars are
obtained using a recently re-calibrated relation between Ca II K-line strength
and (B-V)o colour. The identification of metal-poor stars from this
colour-selection technique is remarkably efficient, and competitive with
previous survey methods. An additional sample of 186 EC stars with
photoelectric colours in the range -0.4 < (B-V)o < 0.3, comprised primarily of
field horizontal-branch stars and other, higher-gravity, A- and B-type stars,
is also analysed. Estimates of the physical parameters Teff, log g, and [Fe/H]
are obtained for cooler members of this subsample, and a number of candidate RR
Lyrae variables are identified.

</DOC>
<DOC>
<DOCNO> 152408 </DOCNO>
Noncommutative N=2 Strings


  We analyze open and mixed sector tree-level amplitudes of N=2 strings in a
space-time with (2,2) signature, in the presence of constant B field. The
expected topological nature of string amplitudes in the open sector is shown to
impose nontrivial constraints on the corresponding noncommutative field theory.
In the mixed sector, we first compute a 3-point function and show that the
corresponding field theory is written in terms of a generalized *-product. We
also analyze a 4-point function (A_{oooc}) of the mixed sector in Theta --->
infinity limit.

</DOC>
<DOC>
<DOCNO> 179056 </DOCNO>
Mean-field models and superheavy elements


  We discuss the performance of two widely used nuclear mean-field models, the
relativistic mean-field theory (RMF) and the non-relativistic
Skyrme-Hartree-Fock approach (SHF), with particular emphasis on the description
of superheavy elements (SHE). We provide a short introduction to the SHF and
RMF, the relations between these two approaches and the relations to other
nuclear structure models, briefly review the basic properties with respect to
normal nuclear observables, and finally present and discuss recent results on
the binding properties of SHE computed with a broad selection of SHF and RMF
parametrisations.

</DOC>
<DOC>
<DOCNO> 120645 </DOCNO>
Noise-driven evolution in stellar systems: A universal halo profile


  Using the theory describing the evolution of a galaxy halo due to stochastic
fluctuations developed in the companion paper, we show that a halo quickly
evolves toward the same self-similar profile, independent of its initial
profile and concentration. The self-similar part of profile takes the form of a
double power law with inner and outer exponents taking the values near -1.5 and
-3 respectively. The precise value of the inner exponent depends on the
magnitude and duration of the noisy epoch and most likely on form of the inner
profile to start. The outer exponent is the result of evolution dominated by
the external l=1 multipole resulting from the inner halo's response to noise.
  Three different noise processes are studied: (1) a bombardment by blobs of
mass small compared to the halo mass (`shrapnel'); (2) orbital evolution of
substructure by dynamical friction (`satellites'); and (3) noise caused by the
orbit of blobs in the halo (`black holes'). The power spectra in the shrapnel
and satellite cases is continuous and results in the double power law form,
independent of initial conditions. The power spectrum for black holes is
discrete and has a different form with a much slower rate of evolution. A
generic prediction of this study is that noise from transient processes will
drive evolution toward the same double power law with only weak constraints on
the noise source and initial conditions.

</DOC>
<DOC>
<DOCNO> 102697 </DOCNO>
Bernstein-Gelfand-Gelfand complexes and cohomology of nilpotent groups


  We show that for $p$small highest weight $\lambda$, 1) there is a
$\Z_p$-integral version of the Bernstein-Gelfand-Gelfand complex, still a
direct summand subcomplex of the standard complex for $V(\lambda)$ 2)
Similarly, a $\Z_p$-integral (as well as a mod. p) version of Kostant formula
holds true. This paper is a companion paper to the one by Mokrane-Tilouine (AG,
subm. 12/12/00), where these results are requested.

</DOC>
<DOC>
<DOCNO> 8227 </DOCNO>
Linear and Nonlinear Experimental Regimes of Stochastic Resonance


  We investigate the stochastic resonance phenomenon in a physical system based
on a tunnel diode. The experimental control parameters are set to allow the
control of the frequency and amplitude of the deterministic modulating signal
over an interval of values spanning several orders of magnitude. We observe
both a regime described by the linear response theory and the nonlinear
deviation from it. In the nonlinear regime we detect saturation of the power
spectral density of the output signal detected at the frequency of the
modulating signal and a dip in the noise level of the same spectral density.
When these effects are observed we detect a phase and frequency synchronization
between the stochastic output and the deterministic input.

</DOC>
<DOC>
<DOCNO> 122105 </DOCNO>
Activity and Kinematics of M and L Dwarfs


  I discuss observations of two traditional age indicators, chromospheric
activity and kinematics, in late-M and L dwarfs near the hydrogen-burning
limit. The frequency and strength of chromospheric activity disappears rapidly
as a function of temperature over spectral types M8-L4. There is evidence that
young late-M and L dwarfs have weaker activity than older ones, the opposite of
the traditional stellar age-activity relation. The kinematics of L dwarfs
confirm that lithium L dwarfs are younger than non-lithium dwarfs.

</DOC>
<DOC>
<DOCNO> 121578 </DOCNO>
Morphological Number Counts and Redshift Distributions to I = 25 from


  We combine magnitude and photometric redshift data on galaxies in the Hubble
Deep Fields with morphological classifications in order to separate out the
distributions for early type galaxies. The updated morphological galaxy number
counts down to I = 25 and the corresponding redshift distributions are used as
joint constraints on cosmological models, in particular on the values of the
density parameter Omega_{0} and normalised cosmological constant Lambda_{0}.
  We find that an Einstein - de Sitter universe with simple passive evolution
gives an excellent fit to the counts and redshift data at all magnitudes. An
open, low Omega_{0}, model with no net evolution (and conservation of the
number of ellipticals), which fits the counts equally well, is somewhat less
successful, predicting slightly lower mean redshifts and, more significantly,
the lack of a high--z tail. A number conserving model with a dominant
contribution from Lambda_{0}, on the other hand, is far less successful,
predicting a much narrower distribution than seen. More complex models are
obviously possible, but we conclude that if large scale transmutation between
types does {\it not} occur, then the lambda-dominated models provide a very
poor fit to the current data.

</DOC>
<DOC>
<DOCNO> 119135 </DOCNO>
Star Formation and Galaxy Environment


  The dependence of star formation rate on galaxian environment is a key issue
in the understanding of galaxy formation and evolution. However, the study of
this subject is complex and observationally challenging. This paper reviews
some of the current results, drawing mostly from recent large redshift surveys
such the LCRS, the MORPH collaboration, and the CNOC1 and CNOC2 redshift
surveys.

</DOC>
<DOC>
<DOCNO> 85506 </DOCNO>
Dynamical Body Frames, Orientation-Shape Variables and Canonical Spin


  After the separation of the center-of-mass motion, a new privileged class of
canonical Darboux bases is proposed for the non-relativistic N-body problem by
exploiting a geometrical and group theoretical approach to the definition of
{\it body frame} for deformable bodies. This basis is adapted to the rotation
group SO(3), whose canonical realization is associated with a symmetry
Hamiltonian {\it left action}. The analysis of the SO(3) coadjoint orbits
contained in the N-body phase space implies the existence of a {\it spin frame}
for the N-body system. Then, the existence of appropriate non-symmetry
Hamiltonian {\it right actions} for non-rigid systems leads to the construction
of a N-dependent discrete number of {\it dynamical body frames} for the N-body
system, hence to the associated notions of {\it dynamical} and {\it measurable}
orientation and shape variables, angular velocity, rotational and vibrational
configurations. For N=3 the dynamical body frame turns out to be unique and our
approach reproduces the {\it xxzz gauge} of the gauge theory associated with
the {\it orientation-shape} SO(3) principal bundle approach of Littlejohn and
Reinsch. For $N \geq 4$ our description is different, since the dynamical body
frames turn out to be {\it momentum dependent}. The resulting Darboux bases for
$N\geq 4$ are connected to the coupling of the {\it spins} of particle clusters
rather than the coupling of the {\it centers of mass} (based on Jacobi relative
normal coordinates). One of the advantages of the spin coupling is that, unlike
the center-of-mass coupling, it admits a relativistic generalization.

</DOC>
<DOC>
<DOCNO> 118912 </DOCNO>
IC3328: a "dwarf elliptical galaxy" with spiral structure


  We present the 2-D photometric decomposition of the Virgo galaxy IC3328. The
analysis of the global light distribution of this morphologically classified
nucleated dwarf elliptical galaxy (dE1,N) reveals a tightly wound, bi-symmetric
spiral structure with a diameter of 4.5 kpc, precisely centered on the nucleus
of the dwarf. The amplitude of the spiral is only three percent of the dwarf's
surface brightness making it the faintest and smallest spiral ever found in a
galaxy. In terms of pitch angle and arm winding the spiral is similar to the
intermediate-type galaxy M51, but it lacks the dust and prominent HII regions
which signal the presence of gas. The visual evidence of a spiral pattern in an
early-type dwarf galaxy reopens the question on whether these dwarfs are
genuine rotationally supported or anisotropic stellar systems. In the case of
IC3328, we argue for a nearly face-on disk (dS0) galaxy with an estimated
maximum rotation velocity of v_c,max = 55kms-1. The faintness of the spiral and
the small motions within it, suggests that we could be seeing swing-amplified
noise. The other possibility is a tidal origin, caused by the near passage of a
small companion.

</DOC>
<DOC>
<DOCNO> 178623 </DOCNO>
Properties of superdeformed fission isomers in the cranked relativistic


  The rotational and deformation properties of superdeformed fission isomers in
the $A\sim 240$ mass region have been investigated within the framework of the
cranked relativistic Hartree-Bogoliubov theory. The dependence of the results
of the calculations on the parametrization of the RMF Lagrangian has been
studied. The rotational properties are best described by the NL1 force.

</DOC>
<DOC>
<DOCNO> 69044 </DOCNO>
Physics potential at a neutrino factory: can we benefit from more than


  In order to fully address the oscillation processes at a neutrino factory, a
detector should be capable of identifying and measuring all three charged
lepton flavors produced in charged current interactions {\it and} of measuring
their charges to discriminate the incoming neutrino helicity. This is an
experimentally challenging task, given the required detector mass for
long-baseline experiments. We address the benefit of a high-granularity,
excellent-calorimetry non-magnetized target-detector, which provides a
background-free identification of electron neutrino charged current and a
kinematical selection of tau neutrino charged current interactions. We assume
that charge discrimination is only available for muons reaching an external
magnetized-Fe spectrometer. This allows the clean classification of events into
electron, right-sign muon, wrong-sign muon and no-lepton categories. In
addition, high granularity permits a clean detection of quasi-elastic events,
which by detecting the final state proton, provide a selection of the neutrino
electron helicity without the need of an electron charge measurement. From
quantitative analyses of neutrino oscillation scenarios, we conclude that in
many cases the discovery sensitivities and the measurements of the oscillation
parameters are dominated by the ability to measure the muon charge. However, we
identify cases where identification of electron and tau samples contributes
significantly.

</DOC>
<DOC>
<DOCNO> 85447 </DOCNO>
Finiteness of a spinfoam model for euclidean quantum general relativity


  We prove that a certain spinfoam model for euclidean quantum general
relativity, recently defined, is finite: all its all Feynman diagrams converge.
The model is a variant of the Barrett-Crane model, and is defined in terms of a
field theory over SO(4) X SO(4) X SO(4) X SO(4).

</DOC>
<DOC>
<DOCNO> 8437 </DOCNO>
Spin quantization axis dependent magnetic properties and x-ray magnetic


  We have performed a theoretical study of the magnetic circular dichroism in
the x-ray absorption spectra (XMCD) of the equiatomic CoPt and FePt ordered
alloys as a function of the spin quantization axis. We found that the
magnetization axis is along the [001] direction and the magneto-crystalline
anisotropy energy (MCA) for the FePt compound is twice as large as that of the
CoPt compound in agreement with experiment. The band structure and the total
density of states confirm that all electronic states contribute to the MCA, and
not just the states at the vicinity of the Fermi level. The orbital magnetic
moments decrease with respect to the angle between the [001] axis and the spin
quantization axis, and are much larger for the CoPt compound. We show that the
orbital moment anisotropy is reflected in the XMCD signal.

</DOC>
<DOC>
<DOCNO> 120472 </DOCNO>
Acceleration of UHE Cosmic Rays in Gamma-Ray Bursts


  Gamma-Ray Bursts are good candidates of the ``bottom up'' scenario for the
generation of the UHE Cosmic Rays. In the most discussed model of GRBs, namely
the ``fireball'' model, a highly relativistic shock forms and seems capable of
accelerating the cosmic rays up to the EeV range. However, only the first Fermi
cycle produces a large energy gain to particles coming from the external
medium. Thus, a complementary acceleration is proposed, downstream of the
external shock, in the relativistic plasma of the GRBs, where crossings of
relativistic fronts are likely to occur. Both forward and backward fronts are
necessary for the internal Fermi acceleration to work and the physical process
that generates them is presented. We found that there exists a relevant
physical process similar to Brillouin backscattering that redistributes the
incoming energy in the plasma shell. This redistribution occurs through the
generation of sound waves that heat the plasma shell and also through the
generation of both forward and backward relativistic Alfven fronts that
accelerate cosmic rays by the Fermi process. We show that this ensemble of
processes is able to account for the generation of UHE cosmic rays.
 There are two opportunities for these combined processes, first during the
``primary'' Gamma-Ray Burst where baryons are entrained by the relativistic
pair wind, second during the predeceleration and deceleration stages when the
fireball interacts with the interstellar medium. However, because of the
synchrotron losses, only the second stage can produce the UHE cosmic rays.

</DOC>
<DOC>
<DOCNO> 69047 </DOCNO>
On transverse energy production in hadron collisions


  The transverse energy spectrum in the unit rapidity window in p-bar p
collisions at 540 GeV c.m.s energy is calculated to the next-to-leading order
accuracy O(a_s^3) and compared to the experimental data by UA(2) collaboration.
We show that the calculated spectrum starts matching experimental data only at
relatively large transverse energy Et=60 GeV and is in essential disagreement
with it both in shape and magnitude at lower transverse energies. The data are
well reproduced by HIJING Monte-Carlo generator indicating the crucial
importance of all-order effects in perturbation theory as well as those of
hadronization in describing the transverse energy production in hadron
collisions at small and intermediate transverse energies.

</DOC>
<DOC>
<DOCNO> 152339 </DOCNO>
Open string derivation of winding states in thermal noncommutative field


  The `winding state' behavior appears in the two-loop nonplanar contribution
to the partition function in thermal noncommutative field theories. We derive
this feature directly from the purely open string theory analysis in the
presence of the constant background $B$-field; we compute the two-loop
partition function for worldsheets with a handle and a boundary when the time
direction of the Euclideanized target space is compactified. In contrast to the
closed-string-inspired approach, it is not necessary to add infinite number of
extra degrees of freedom. Furthermore, we find a piece of supporting evidence
toward the conjecture that, in the UV limit, the noncommutativity parameter
plays the role of the effective string scale in noncommutative field theories.

</DOC>
<DOC>
<DOCNO> 13974 </DOCNO>
Statistical properties of inelastic Lorentz gas


  The inelastic Lorentz gas in cooling states is studied. It is found that the
inelastic Lorentz gas is localized and that the mean square displacement of the
inelastic Lorentz gas obeys a power of a logarithmic function of time. It is
also found that the scaled position distribution of the inelastic Lorentz gas
has an exponential tail, while the distribution is close to the Gaussian near
the peak. Using a random walk model, we derive an analytical expression of the
mean square displacement as a function of time and the restitution coefficient,
which well agrees with the data of our simulation. The exponential tail of the
scaled position distribution function is also obtained by the method of
steepest descent.

</DOC>
<DOC>
<DOCNO> 121947 </DOCNO>
Stellar Variability in the Globular Cluster Terzan 5


  We present the results of a search for variability in and near the core of
the metal-rich, obscured globular cluster Terzan 5, using NICMOS on HST. This
extreme cluster has approximately solar metallicity and a central density that
places it in the upper few percent of all clusters. It is estimated to have the
highest interaction rate of any galactic globular cluster. The large extinction
towards Terzan 5 and the severe stellar crowding near the cluster center
present a substantial observational challenge. Using time series analysis we
discovered two variable stars in this cluster. The first is a RRab Lyrae
variable with a period of ~0.61 days, a longer period than that of field stars
with similar high metallicities. This period is, however, shorter than the
average periods of RR Lyraes found in the metal-rich globular clusters NGC
6441, NGC 6388 and 47 Tuc. The second variable is a blue star with a 7-hour
period sinusoidal variation and a likely orbital period of 14 hours. This star
is probably an eclipsing blue straggler, or (less likely) the infrared
counterpart to the low mass X-ray binary known in Terzan 5. Due to the extreme
crowding and overlapping Airy profile of the IR PSF, we fall short of our
original goal of detecting CVs via Palpha emission and detecting variable
infrared emission from the location of the binary MSP in Terzan 5.

</DOC>
<DOC>
<DOCNO> 70066 </DOCNO>
Renormalization of supersymmetric Yang-Mills theories with soft


  The renormalization of supersymmetric Yang-Mills theories with soft
supersymmetry breaking is presented using spurion fields for introducing the
breaking terms. It is proven that renormalization of the fields and parameters
in the classical action yields precisely the correct counterterms to cancel all
divergences. In the course of the construction of higher orders additional
independent parameters appear, but they can be shown to be irrelevant in
physics respects. Thus, the only parameters with influence on physical
amplitudes are the supersymmetric and the well-known soft breaking parameters.

</DOC>
<DOC>
<DOCNO> 101834 </DOCNO>
An intrinsic homotopy theory for simplicial complexes, with applications


  A simplicial complex is a set equipped with a down-closed family of
distinguished finite subsets. This structure, usually viewed as codifying a
triangulated space, is used here directly, to describe "spaces" whose geometric
realisation can be misleading. An intrinsic homotopy theory, not based on such
realisation but agreeing with it, is introduced.
   The applications developed here are aimed at image analysis in metric spaces
and have connections with digital topology and mathematical morphology. A
metric space X has a structure of simplicial complex at each (positive)
resolution e; the resulting n-homotopy group detects those singularities which
can be captured by an n-dimensional grid, with edges bound by e; this works
equally well for continuous or discrete regions of euclidean spaces. Its
computation is based on direct, intrinsic methods.

</DOC>
<DOC>
<DOCNO> 116570 </DOCNO>
New families of supercompact objects and a gravitational mechanism for


  It is shown, that a topological difference between Newtonnian and
relativistic gravity leads to some observable effects and it allow predict a
hierarchy of supercompact objects - multibaryonic, quark and (possible)
subquark stars instead of black holes. A reflection on the source of a falling
matter (mirror horizon effect) leads to a gravitational breathing of exterior
layers of stars and a multiperiodicity of spectrum of supercompact stars (or
nucleys of stars and galaxies).

</DOC>
<DOC>
<DOCNO> 99485 </DOCNO>
New moduli spaces of pointed curves and pencils of flat connections


  It is well known that formal solutions to the Associativity Equations are the
same as cyclic algebras over the homology operad $(H_*(\bar{M}_{0,n+1}))$ of
the moduli spaces of $n$--pointed stable curves of genus zero. In this paper we
establish a similar relationship between the pencils of formal flat connections
(or solutions to the Commutativity Equations) and homology of a new series
$\bar{L}_n$ of pointed stable curves of genus zero. Whereas $\bar{M}_{0,n+1}$
parametrizes trees of $\bold{P}^1$'s with pairwise distinct nonsingular marked
points, $\bar{L}_n$ parametrizes strings of $\bold{P}^1$'s stabilized by marked
points of two types. The union of all $\bar{L}_n$'s forms a semigroup rather
than operad, and the role of operadic algebras is taken over by the
representations of the appropriately twisted homology algebra of this union.

</DOC>
<DOC>
<DOCNO> 99599 </DOCNO>
Szego kernels and a theorem of Tian


  We give a simple proof of Tian's theorem that the Kodaira embeddings
associated to a positive line bundle over a compact complex manifold are
asymptotically isometric. The proof is based on the diagonal asymptotics of the
Szego kernel (i.e. the orthogonal projection onto holomorphic sections). In
deriving these asymptotics we use the Boutet de Monvel-Sjostrand parametrix for
the Szego kernel.

</DOC>
<DOC>
<DOCNO> 119500 </DOCNO>
X-Ray Variability of NLS1s and BLS1s


  Evenly-sampled hard X-ray monitoring was obtained with RXTE for one NLS1 (Akn
564) and four BLS1s. The variability amplitude of the NLS1 was no larger than
the mean of the BLS1s, and the NLS1 showed stronger variability in the harder
portion of the RXTE band, while the BLS1s were more strongly variable in the
relatively soft part of the band. This contribution discusses possible
explanations for these surprising results, including possible calibration
errors or systematic differences between long and short time scale variability
in NLS1s and BLS1s.

</DOC>
<DOC>
<DOCNO> 80871 </DOCNO>
Center Vortices at Strong Couplings


  A long-range effective action is derived for strong-coupling lattice SU(2)
gauge theory in D=3 dimensions. It is shown that center vortices emerge as
stable saddlepoints of this action.

</DOC>
<DOC>
<DOCNO> 117625 </DOCNO>
WWhat Heavy Elements in Clusters of Galaxies Tell About Clusters and


  Clusters of galaxies allow a direct estimate of the metallicity and metal
production yield on the largest scale so far. The ratio of the total iron mass
in the ICM to the total optical luminosity of the cluster (the iron
mass-to-light-ratio) is the same for all clusters which ICM is hotter than
$\sim 2$ keV, and the elemental proportions (i.e. the [$\alpha$/Fe] ratio)
appear to be solar. The simplest interpretation of these evidences is that both
the IMF as well the relative contributions of SN types are universal. Currently
available abundances in cooler clusters and groups are much more uncertain,
possibly due to insufficiently accurate atomic physics data for multi-electron
ions, or to the ICM being multi-phase, or to a combination thereof. This
uncertainty automatically extends to the reality of radial abundance gradients
so far reported in cool clusters. It is emphasized that most metals reside in
the ICM rather than in galaxies, which demonstrates that energetic winds
operated early in the evolution of massive galaxies, the likely producers of
most metals now in the ICM. The ICM metallicity is also used to set a
semiempirical constraint of $\sim 0.1$ keV per particle to the ICM {\it
preheating} due to supernova driven galactic winds. A lower limit of the
universe global metallicity at $z=3$ is also mentioned.

</DOC>
<DOC>
<DOCNO> 120246 </DOCNO>
The plasma-solid transition:two simple examples


  Using a simple criterion proposed by Kirzhnitz,we have discussed the
plasma-solid transition in two simple model cases: the Fermi-Dirac and Bose
Einstein gas.Some possibilities of astrophysical applications of our results
are also indicated.

</DOC>
<DOC>
<DOCNO> 101229 </DOCNO>
Newton polygons and formal groups: Conjectures by Manin and Grothendieck


  We consider p-divisible groups (also called Barsotti-Tate groups) in
characteristic p, their deformations, and we draw some conclusions.
  For such a group we can define its Newton polygon (abbreviated NP). This is
invariant under isogeny. For an abelian variety (in characteristic p) the
Newton polygon of its p-divisible group is ``symmetric''.
  In 1963 Manin conjectured that conversely any symmetric Newton polygon is
``algebroid''; i.e., it is the Newton polygon of an abelian variety. This
conjecture was shown to be true and was proved with the help of the
``Honda-Serre-Tate theory''. We give another proof.
  Grothendieck showed that Newton polygons ``go up'' under specialization: no
point of the Newton polygon of a closed fiber in a family is below the Newton
polygon of the generic fiber. In 1970 Grothendieck conjectured the converse:
any pair of comparable Newton polygons appear for the generic and special
fiber of a family. This was extended by Koblitz in 1975 to a conjecture about
a sequence of comparable Newton polygons. We prove these conjectures.

</DOC>
<DOC>
<DOCNO> 11486 </DOCNO>
Superconducing Alloys with Weak and Strong Scattering: Anderson's


  We have studied the effects of strong impurity scattering on disordered
superconductors beyond the low impurity concentration limit. By applying the
full CPA to a superconductiong A-B binary alloy, we calculated the fluctuations
of the local order parameters $\Delta_{A}, \Delta_{B}$ and charge densities,
$n_{A}, n_{B}$ for weak and strong on site disorder. We find that for narrow
band alloy s-wav e superconductors the conditions for Anderson's theorem are
satisfied in general only for the case of particle-hole symmetry. In this case
it is satisfied regardless whether we are in the weak or strong scattering
regimes. Interestingly, we find that strong scattering leads to band splitting
and in this regime for any band filling we have a critical concentration where
a superconductor-insulator quantum phase transition occurs at T=0.

</DOC>
<DOC>
<DOCNO> 100636 </DOCNO>
Semi-Riemannian submersions with totally geodesic fibres


  We classify the semi-Riemannian submersions with totally geodesic fibres from
a real pseudo-hyperbolic space onto a semi-Riemannian manifold under the
assumption that the dimension of fibres is less than or equal to 3. Also we
obtain the classification of the semi-Riemannian submersions with complex
connected and totally geodesic fibres from a complex pseudo-hyperbolic space
onto a semi-Riemannian manifold under the assumption that the dimension of
fibres is less than or equal to 2. We get there are no semi-Riemannian
submersions with quaternionic fibres from a quaternionic pseudo-hyperbolic
space onto a Riemannian manifold.

</DOC>
<DOC>
<DOCNO> 100199 </DOCNO>
Spectra and symmetric spectra in general model categories


  (This is an updated version; following an idea of Voevodsky, we have
strengthened our results so all of them apply to one form of motivic homotopy
theory).
  We give two general constructions for the passage from unstable to stable
homotopy that apply to the known example of topological spaces, but also to new
situations, such as motivic homotopy theory of schemes. One is based on the
standard notion of spectra originated by Boardman. Its input is a well-behaved
model category C and an endofunctor G, generalizing the suspension. Its output
is a model category on which G is a Quillen equivalence. Under strong
hypotheses the weak equivalences in this model structure are the appropriate
analogue of stable homotopy isomorphisms.
  The second construction is based on symmetric spectra, and is of value only
when C has some monoidal structure that G preserves. In this case, ordinary
spectra generally will not have monoidal structure, but symmetric spectra will.
Our abstract approach makes constructing the stable model category of symmetric
spectra straightforward. We study properties of these stabilizations; most
importantly, we show that the two different stabilizations are Quillen
equivalent under some hypotheses (that also hold in the motivic example).

</DOC>
<DOC>
<DOCNO> 12881 </DOCNO>
The effect of temperature on the viscoelastic response of rubbery


  Constitutive equations are derived for the viscoelastic response of rubbery
polymers at finite strains. A polymer is thought of as a network of long chains
connected to temporary junctions. At a random time, a chain detaches from a
junction, which is treated at transition from its active state to the dangling
state. A dangling chain randomly captures a new junction in the vicinity of its
free end and returns to its active state. Breakage and reformation of long
chains are modeled as thermo-mechanically activated processes. Stress-strain
relations for a rubbery polymer are developed using the laws of thermodynamics.
Adjustable parameters in the model are found by fitting observations in
uniaxial tensile tests for a carbon black filled rubber at various
temperatures. Fair agreement is demonstrated between experimental data and
results of numerical simulation.

</DOC>
<DOC>
<DOCNO> 150355 </DOCNO>
Quantization of fields over de Sitter space by the method of generalized


  Connection of the invariant Dirac equation over the de Sitter space with
irreducible representations of the de Sitter group is ascertained. The set of
solutions of this equation is obtained in the form of the product of two
different systems of generalized coherent states for the de Sitter group. Using
these solutions the quantized Dirac field over de Sitter space is constructed
and its propagator is found. It is a result of action of some de Sitter
invariant spinor operator onto the spin zero propagator with an imaginary shift
of a mass.

</DOC>
<DOC>
<DOCNO> 120932 </DOCNO>
ASCA Observations of GX 354-0 and KS 1731-260


  We report on ASCA observations of the low mass X-ray binaries GX 354-0 and KS
1731-260. The spectrum of GX 354-0 is best described as a power-law or a
Comptonized spectrum with tau ~ 5 and kT ~ 8 keV and a residual at ~6.5 keV.
The residual may be a disk reflection or a Compton broadened Gaussian line from
the hot inner ADAF-like coronal region. The absorption column density to the
source is 2.9e22 cm^-2. No soft thermal component was detected. The spectrum
from KS 1731-260 is softer and it is best fit with a two component model with a
column density of 1.1e22 cm^-2. The likely interpretation is emission from a
Comptonizing cloud with an optical depth tau>12 and either a neutron star or a
disk blackbody emission. We discuss the likely location of the Comptonizing
cloud for both sources within the context of several proposed emission models.

</DOC>
<DOC>
<DOCNO> 120642 </DOCNO>
LiBeB, O and Fe Evolution: Refractory Element and Cosmic Ray Transport


  Employing a Monte-Carlo based evolutionary code, we show that the delay of Fe
deposition relative to O, due to the incorporation of supernova ejecta
refractories in high velocity grains, can account for the rise of [O/Fe] with
decreasing [Fe/H]. The predicted behavior of refractory Mg, Si, Ca and Ti, and
volatile S, namely that the refractories should not show the rise, but that the
behavior of S should be similar to that of O, appears to be confirmed (Takeda
et al. 2000, astro-ph/0007007). The delayed deposition of Be, due to cosmic ray
transport in a relatively low density medium, leads to consistency of primary
Be evolution as a function of both [Fe/H] and [O/H].

</DOC>
<DOC>
<DOCNO> 151724 </DOCNO>
Central extended D=2 N=4 SU(2) Liouville self interacting model and


  Methods developed in the context of 2d conformal field theories and
integrable models are used, in the harmonic superspace language, to solve the
system of non linear harmonic differential equations that appear in the central
extension of D=2 N=4 SU(2) Liouville self interacting model and compute the
explicit form of the associated hyperkahler metric. Among the results obtained,
we derive new general solutions for the auxiliary fields and the Lagrange field
and present explicitly the associated purely bosonic dependent action in the
central extension case. We derive also the explicit form of the associated
hyperkahler metric as well as the induced non trivial scalar potential shown to
depend on the square term. This provides then a way to make a comparison with
the standard result in which the term proportional to is known to correspond to
the BPS mass.

</DOC>
<DOC>
<DOCNO> 151691 </DOCNO>
The Quantum Geometry of Spin and Statistics


  Both, spin and statistics of a quantum system can be seen to arise from
underlying (quantum) group symmetries. We show that the spin-statistics theorem
is equivalent to a unification of these symmetries. Besides covering the
Bose-Fermi case we classify the corresponding possibilities for anyonic spin
and statistics. We incorporate the underlying extended concept of symmetry into
quantum field theory in a generalised path integral formulation capable of
handling general braid statistics. For bosons and fermions the different path
integrals and Feynman rules naturally emerge without introducing Grassmann
variables. We also consider the anyonic example of quons and obtain the path
integral counterpart to the usual canonical approach.

</DOC>
<DOC>
<DOCNO> 121525 </DOCNO>
N-body simulations of warped galaxies


  Two methods generating warped galaxies with N-body simulations are presented.
One uses an external potential as a disturber while the other is based on
material accretion. The results of both methods are compared. A particular
attention is given on the shape of the line of node (LON).

</DOC>
<DOC>
<DOCNO> 122638 </DOCNO>
Reviving Fossil Radio Plasma in Clusters of Galaxies by Adiabatic


  We give for a plasma with a history of several expansion and contraction
phases an analytical model of the evolution of a contained relativistic
electron population under synchrotron, inverse Compton and adiabatic energy
losses or gains. This is applied to different scenarios for evolution of radio
plasma inside the cocoons of radio galaxies, after the activity of the central
engine has ceased. It is demonstrated that fossil radio plasma with an age of
even up to 2 Gyr can be revived by compression in a shock wave of large-scale
structure formation, caused during the merging events of galaxy clusters, or by
the accretion onto galaxy clusters. We argue, that this is a highly plausible
explanation for the observed cluster radio relics, which are the regions of
diffuse radio emission found in clusters of galaxies, without any likely parent
radio galaxy seen nearby. An implication of this model is the existence of a
population of diffuse, ultra-steep spectrum, very low frequency radio sources
located inside and possibly outside of clusters of galaxies, tracing the
revival of aged fossil radio plasma by the shock waves associated with
large-scale structure formation.

</DOC>
<DOC>
<DOCNO> 84714 </DOCNO>
$\hat{Q}$ operator for canonical quantum gravity


  We study the properties of $\hat{Q}[\omega]$ operator on the kinematical
Hilbert space ${\cal H}$ for canonical quantum gravity. Its complete spectrum
with respect to the spin network basis is obtained. It turns out that
$\hat{Q}[\omega]$ is diagonalized in this basis, and it is a well defined
self-adjoint operator on ${\cal H}$. The same conclusions are also tenable on
the SU(2) gauge invariant Hilbert space with the gauge invariant spin network
basis.

</DOC>
<DOC>
<DOCNO> 150378 </DOCNO>
Standard Model Vacua in Heterotic M-Theory


  We present a class of N=1 supersymmetric ``standard'' models of particle
physics, derived directly from heterotic M-theory, that contain three families
of chiral quarks and leptons coupled to the gauge group SU(3)_C X SU(2)_L X
U(1)_Y. These models are a fundamental form of ``brane world'' theories, with
an observable and hidden sector each confined, after compactification on a
Calabi--Yau threefold, to a BPS three-brane separated by a higher dimensional
bulk space with size of the order of the intermediate scale. The requirement of
three families, coupled to the fundamental conditions of anomaly freedom and
supersymmetry, constrains these models to contain additional five-branes
located in the bulk space and wrapped around holomorphic curves in the
Calabi--Yau threefold.

</DOC>
<DOC>
<DOCNO> 100266 </DOCNO>
The Semi-Relativistic Equation Via the Shifted-l Expansion Technique


  The semi-relativistic equation is cast into a second-order Schrodinger-like
equation with the inclusion of relativistic corrections up to order (v/c)^2.
The resulting equation is solved via the shifted-l expansion technique, which
has been recently developed to get eigenvalues of relativistic and
non-relativistic wave equations. The Coulomb, Oscillator, and the
Coulomb-plus-linear potential used in qq-bar phenomenology are tested. The
method gives quite accurate results over a wide range of r and any choice of
quantum numbers n and l. However, a comparison of the present work with those
of Lucha et al. and Nickisch et al. will serve as a test of this approach.

</DOC>
<DOC>
<DOCNO> 100967 </DOCNO>
Oriented Quantum Algebras, Categories and Invariants of Knots and Links


  This paper defines the concept of an oriented quantum algebra and develops
its application to the construction of quantum link invariants. We show that
all known quantum link invariants can be put into this framework.

</DOC>
<DOC>
<DOCNO> 170680 </DOCNO>
An Exponentially Fast Quantum Search Algorithm


  The existing quantum search algorithm, due to L.K. Grover, finds a single
search target in a large database with N items in O(N^{1/2}) steps. The speedup
is quadratic. In this paper, we show a new search algorithm whose speedup is
exponential. The iterations are carried out dynamically utilizing varying
auxiliary oracle functions. For a data space with N items, our quantum
algorithm homes in on the single search target in no more than
2*ceiling(log_4{N}) iterations.

</DOC>
<DOC>
<DOCNO> 67841 </DOCNO>
Muon g-2 and precision electroweak physics in the MSSM


  The minimal supersymmetric extension of standard model (MSSM) is examined by
analyzing its quantum effects on the precision electroweak measurements and the
muon g-2. We examine carefully the effects of light charginos and neutralinos
that are found to improve the fit to the electroweak data. We identify two
distinct regions on the $(\mu, M_2)$-plane that fit well to the electroweak
data and give significant contribution to muon g-2.

</DOC>
<DOC>
<DOCNO> 13351 </DOCNO>
Ab intio calculation of the Transmission Coefficients from a


  A new formalism to calculate the transmission coefficient t of electrons from
a material L into the same material L through a barrier B is presented. The
barrier B is arbitrary and can be metallic, semiconducting or insulating. The
important feature of this formalism is that it starts from the electronic
structure of a periodic L/B superlattice. The electronic stucture of such a
superlattice is calculated selfconsistently within a Screened
Korringa-Kohn-Rostoker method. The capability of the new method is demonstrated
by means of a free electron model. First results for the transmission of Cu
electrons through a Co layer are presented.

</DOC>
<DOC>
<DOCNO> 68279 </DOCNO>
Nonperturbative Gluon Radiation and Energy Dependence of Elastic


  The energy dependence of the total hadronic cross sections is caused by gluon
bremsstrahlung which we treat nonperturbatively. It is located at small
transverse distances about 0.3 fm from the valence quarks. The cross section of
gluon radiation is predicted to exponentiate and rise with energy as s^{\Delta}
with \Delta=0.17 +/- 0.01. The total cross section also includes a large energy
independent Born term which corresponds to no gluon radiation. The calculated
total cross section and the slope of elastic scattering are in good agreement
with the data.

</DOC>
<DOC>
<DOCNO> 99764 </DOCNO>
On the existence of absolutely simple abelian varieties of a given


  We prove that for every field k and every positive integer n, there exists an
absolutely simple n-dimensional abelian variety over k. We also prove an
asymptotic result for finite fields: For every finite field k and positive
integer n, we let S(k,n) denote the fraction of the isogeny classes of
n-dimensional abelian varieties over k that consist of absolutely simple
ordinary abelian varieties. Then for every n, the quantity S(F_q,n) approaches
1 as q approaches infinity over the prime powers.

</DOC>
<DOC>
<DOCNO> 120031 </DOCNO>
Implications of Binary Properties for Theories of Star Formation


  The overall frequency and other statistical properties of binary systems
suggest that star formation is intrinsically a complex and chaotic process, and
that most binaries and single stars actually originate from the decay of
multiple systems. Interactions between stars forming in close proximity to each
other may play an important role in the star formation process itself, for
example via tidally induced accretion from disks. Some of the energetic
activity of newly formed stars could be due to bursts of rapid accretion
triggered by interactions with close companions.

</DOC>
<DOC>
<DOCNO> 118733 </DOCNO>
Discovery of a New Deeply Eclipsing SU UMa-Type Dwarf Nova, IY UMa (=


  We discovered a new deeply eclipsing SU UMa-type dwarf nova, IY UMa, which
experienced a superoutburst in 2000 January. Our monitoring revealed two
distinct outbursts, which suggest a superoutburst interval of ~800 d, or its
half, and an outburst amplitude of 5.4 mag. From time-series photometry during
the superoutburst, we determined a superhump and orbital period of 0.07588 d
and 0.0739132 d, respectively.

</DOC>
<DOC>
<DOCNO> 13829 </DOCNO>
The thermohydrodynamical picture of a charged Brownian particle


  We study a charged Brownian gas with a non uniform bath temperature, and
present a thermohydrodynamical picture. Expansion on the collision time probes
the validity of the local equilibrium approach and the relevant thermodynamical
variables. For the linear regime we present several applications (including
some novel results). For the lowest nonlinear expansion and uniform bath
temperature we compute the gradient corrections to the local equilibrium
approach and the fundamental (Smoluchowsky) equation for the nonequilibrium
particle density.

</DOC>
<DOC>
<DOCNO> 84923 </DOCNO>
The impact of tidal errors on the determination of the Lense-Thirring


  The general relativistic Lense-Thirring effect can be detected by means of a
suitable combination of orbital residuals of the laser-ranged LAGEOS and LAGEOS
II satellites. While this observable is not affected by the orbital
perturbation induced by the zonal Earth solid and ocean tides, it is sensitive
to those generated by the tesseral and sectorial tides. The assessment of their
influence on the measurement of the parameter mu, with which the
gravitomagnetic effect is accounted for, is the goal of this paper. After
simulating the combined residual curve by calculating accurately the
mismodeling of the more effective tidal perturbations, it has been found that,
while the solid tides affect the recovery of mu at a level always well below
1%, for the ocean tides and the other long-period signals Delta mu depends
strongly on the observational period and the noise level: Delta mu(tides)
amounts to almost 2% after 7 years. The aliasing effect of K1 l=3 p=1 tide and
SRP(4241) solar radiation pressure harmonic, with periods longer than 4 years,
on the perigee of LAGEOS II yield to a maximum systematic uncertainty on
$\m_{LT}$ of less than 4% over different observational periods. The zonal
18.6-year tide does not affect the combined residuals.

</DOC>
<DOC>
<DOCNO> 116793 </DOCNO>
A Note on $3 + 1$ Dimensionality


  Recent work by Castro, Granik and El Naschie has given a rationale for the
three dimensionality of our physical space within the framework of cantorian
fractal space time using similar ideas of quantized fractal space time and
noncommutativity. We also deduce the same result. Interestingly this is also
seen to provide a rationale for an unproven conjecture of Poincare.

</DOC>
<DOC>
<DOCNO> 10471 </DOCNO>
Bistability and hysteresis in tilted sandpiles


  We show that tilting a model sandpile that has dynamic disorder leads to
bistability and hysteresis at the angle of repose. Also the distribution of
{\it local slopes} shows an interesting dependence on the amount of tilt -
weakly tilted sandpiles retain the quasi-continuous distributions of the steady
state, while large tilt makes the distribution more discrete, with local slopes
clustered round particular values. These observations are used to explain
recent experimental results on avalanche shapes; we give a theoretical
framework in terms of directed percolation.

</DOC>
<DOC>
<DOCNO> 119225 </DOCNO>
Acceleration of CR at Large Scale Shocks and Their Cosmological Role for


  We investigate the dynamical importance of a newly recognized possible source
of significant feedback generated during structure formation; namely cosmic ray
(CR) pressure. We present evidence for the existence of numerous shocks in the
hot gas of galaxy clusters (GCs). We employ for the first time an explicit
numerical treatment of CR acceleration and transport in hydro simulations of
structure formation. According to our results, CRs provide an important
fraction of the total pressure inside GCs, up to several tenths. This was true
even at high redshift (z=2), meaning that such non-thermal component could
affect the evolution of structure formation.

</DOC>
<DOC>
<DOCNO> 71081 </DOCNO>
Hadronic interactions of the J/psi


  We calculate the cross sections for reactions of the J/psi with light mesons.
We also evaluate its finite temperature spectral function. We investigate
separately the role of elastic and inelastic channels and we compare their
respective importance. We describe J/psi absorption channels that have not been
considered previously to our knowledge. The relevance of our study to heavy ion
collisions is discussed.

</DOC>
<DOC>
<DOCNO> 119762 </DOCNO>
How to fool CMB parameter estimation


  With the release of the data from the Boomerang and MAXIMA-1 balloon flights,
estimates of cosmological parameters based on the Cosmic Microwave Background
(CMB) have reached unprecedented precision. In this paper I show that it is
possible for these estimates to be substantially biased by features in the
primordial density power spectrum. I construct primordial power spectra which
mimic to within cosmic variance errors the effect of changing parameters such
as the baryon density and neutrino mass, meaning that even an ideal measurement
would be unable to resolve the degeneracy. Complementary measurements are
necessary to resolve this ambiguity in parameter estimation efforts based on
CMB temperature fluctuations alone.

</DOC>
<DOC>
<DOCNO> 117450 </DOCNO>
Multi-wavelength Observations of Dusty Star Formation at Low and High


  This paper examines what can be learned about high-redshift star formation
from the small fraction of high-redshift galaxies' luminosities that is emitted
at accessible wavelengths. We review and quantify empirical correlations
between bolometric luminosities produced by star formation and the UV, mid-IR,
sub-mm, and radio luminosities of galaxies in the local universe. These
correlations suggest that observations of high-redshift galaxies at any of
these wavelengths should constrain their star-formation rates to within
0.2--0.3 dex. We assemble the limited evidence that high-redshift galaxies obey
these locally calibrated correlations. The characteristic luminosities and dust
obscurations of galaxies at z ~ 0, z ~ 1, and z ~ 3 are reviewed. After
discussing the relationship between the high-redshift populations selected in
surveys at different wavelengths, we calculate the contribution to the 850um
background from each. The available data show that a correlation between
star-formation rate and dust obscuration L_dust/L_UV exists at low and high
redshift. This correlation plays a central role in the major conclusion of this
paper: most star formation at high redshift occurred in galaxies with 1 <
L_dust/L_UV < 100 similar to those that host the majority of star formation in
the local universe and to those that are detected in UV-selected surveys.
(abridged)

</DOC>
<DOC>
<DOCNO> 69176 </DOCNO>
Largest temperature of the radiation era and its cosmological


  The thermal history of the universe before the epoch of nucleosynthesis is
unknown. The maximum temperature in the radiation-dominated era, which we will
refer to as the reheat temperature, may have been as low as 0.7 MeV. In this
paper we show that a low reheat temperature has important implications for many
topics in cosmology. We show that weakly interacting massive particles (WIMPs)
may be produced even if the reheat temperature is much smaller than the
freeze-out temperature of the WIMP, and that the dependence of the present
abundance on the mass and the annihilation cross section of the WIMP differs
drastically from familiar results. We revisit predictions of the relic
abundance and resulting model constraints of supersymmetric dark matter,
axions, massive neutrinos, and other dark matter candidates, nucleosynthesis
constraints on decaying particles, and leptogenesis by decay of superheavy
particles. We find that the allowed parameter space of supersymmetric models is
altered, removing the usual bounds on the mass spectrum; the cosmological bound
on massive neutrinos is drastically changed, ruling out Dirac (Majorana)
neutrino masses $m_\nu$ only in the range 33 keV $\simlt m_\nu\simlt$ 6 (5)
MeV, which is significantly smaller from the the standard disallowed range 94
eV $\simlt m_\nu\simlt$ 2 GeV (this implies that massive neutrinos may still
play the role of either warm or cold dark matter); the cosmological upper bound
on the Peccei-Quinn scale may be significantly increased to $ 10^{16}$GeV from
the usually cited limit of about $10^{12}$GeV; and that efficient
out-of-equilibrium GUT baryogenesis and/or leptogenesis can take place even if
the reheat temperature is much smaller than the mass of the decaying superheavy
particle.

</DOC>
<DOC>
<DOCNO> 8287 </DOCNO>
Supercooled confined water and the Mode Coupling crossover temperature


  We present a Molecular Dynamics study of the single particle dynamics of
supercooled water confined in a silica pore. Two dynamical regimes are found:
close to the hydrophilic substrate molecules are below the Mode Coupling
crossover temperature, $T_C$, already at ambient temperature. The water closer
to the center of the pore (free water) approaches upon supercooling $T_C$ as
predicted by Mode Coupling Theories. For free water the crossover temperature
and crossover exponent $\gamma$ are extracted from power-law fits to both the
diffusion coefficient and the relaxation time of the late $\alpha$ region.

</DOC>
<DOC>
<DOCNO> 102863 </DOCNO>
Deformation Invariance of Plurigenera


  We prove the invariance of plurigenera under smooth projective deformations
in full generality. The proof is done by several estimates of singular
hermitian metrics in terms of $L^{2}$-extension theorem of holomorphic
sections.

</DOC>
<DOC>
<DOCNO> 119885 </DOCNO>
Inner edge of neutron-star crust with SLy effective nucleon-nucleon


  The boundary between the solid crust, assumed to be in complete thermodynamic
equilibrium (cold catalyzed matter), and the liquid core of a neutron star is
studied using Skyrme SLy effective N-N interactions. An approximate value of
the density at the inner edge of the crust is obtained from the threshold for
the instability of homogeneous $npe$ matter with respect to small periodic
density perturbations. Calculations of the bottom layer of the crust are
performed within the Compressible Liquid Drop Model. Spherical nuclei are
energetically preferred over exotic ones (cylinders, plates, tubes, bubbles),
down to the inner edge of the crust, found at the density 0.08 fm^{-3}.

</DOC>
<DOC>
<DOCNO> 119752 </DOCNO>
Discovery of X-ray Emission from G328.4+0.2, a Crab-Like Supernova


  G328.4+0.2 is a moderately small (5 arcmin x 5arcmin) Galactic radio
supernova remnant (SNR) at a distance of at least 17 kpc that has been long
suggested to be Crab-like. Here we report on the detection with ASCA of the
X-ray emission from the SNR. The X-ray source is faint with an observed flux of
(6.0 +/- 0.8)E-13 erg/s/cm^2 over the 2-10 keV band. The emission is heavily
cut-off at low energies and no flux is detected below 2 keV. Spectral analysis
confirms that the column density to the source is indeed large, N_H ~ 1E23
atoms/cm^2, and consistent with the total column density of hydrogen through
the Galaxy at this position. Good fits to the spectrum can be obtained for
either thermal plasma or nonthermal power-law models, although the lack of
detected line emission as well as other evidence argues against the former
interpretation. The power-law index we find, \alpha_P = 2.9 (+0.9,-0.8), is
consistent with other Crab-like SNRs. In the radio band G328.4+0.2 is nearly as
luminous as the Crab Nebula, yet in the X-ray band luminosity it is some 70
times fainter. Nevertheless its inferred soft X-ray band luminosity is greater
than all but the brightest pulsar-powered synchrotron nebulae and implies that
G328.4+0.2 contains a rapidly spinning, as yet undetected, pulsar that is
losing energy at a rate of approximately 1E38 erg/s.

</DOC>
<DOC>
<DOCNO> 13810 </DOCNO>
Rapid algorithm for identifying backbones in the two-dimensional


  We present a rapid algorithm for identifying the current-carrying backbone in
the percolation model. It applies to general two-dimensional graphs with open
boundary conditions. Complemented by the modified Hoshen-Kopelman cluster
labeling algorithm, our algorithm identifies dangling parts using their local
properties. For planar graphs, it finds the backbone almost four times as fast
as Tarjan's depth-first-search algorithm, and uses the memory of the same size
as the modified Hoshen-Kopelman algorithm. Comparison with other algorithms for
backbone identification is addressed.

</DOC>
<DOC>
<DOCNO> 119616 </DOCNO>
Chandra Discovery of a 100 kpc X-ray Jet in PKS 0637--752


  The quasar PKS 0637-753, the first celestial X-ray target of the Chandra
X-ray Observatory, has revealed asymmetric X-ray structure extending from 3 to
12 arcsec west of the quasar, coincident with the inner portion of the jet
previously detected in a 4.8 GHz radio image (Tingay et al. 1998). At a
redshift of z=0.651, the jet is the largest (~100 kpc) and most luminous
(~10^{44.6} ergs/s) of the few so far detected in X-rays. This letter presents
a high resolution X-ray image of the jet, from 42 ks of data when PKS 0637-753
was on-axis and ACIS-S was near the optimum focus. For the inner portion of the
radio jet, the X-ray morphology closely matches that of new ATCA radio images
at 4.8 and 8.6 GHz. Observations of the parsec scale core using the VSOP space
VLBI mission show structure aligned with the X-ray jet, placing important
constraints on the X-ray source models. HST images show that there are three
small knots coincident with the peak radio and X-ray emission. Two of these are
resolved, which we use to estimate the sizes of the X-ray and radio knots. The
outer portion of the radio jet, and a radio component to the east, show no
X-ray emission to a limit of about 100 times lower flux.
  The X-ray emission is difficult to explain with models that successfully
account for extra-nuclear X-ray/radio structures in other active galaxies. We
think the most plausible is a synchrotron self-Compton (SSC) model, but this
would imply extreme departures from the conventional minimum-energy and/or
homogeneity assumptions. We also rule out synchrotron or thermal bremsstrahlung
models for the jet X-rays, unless multicomponent or ad hoc geometries are
invoked.

</DOC>
<DOC>
<DOCNO> 122611 </DOCNO>
Local Dynamical Instabilities in Magnetized, Radiation Pressure


  We present a general linear dispersion relation which describes the coupled
behavior of magnetorotational, photon bubble, and convective instabilities in
weakly magnetized, differentially rotating accretion disks. We presume the
accretion disks to be geometrically thin and supported vertically by radiation
pressure. We fully incorporate the effects of a nonzero radiative diffusion
length on the linear modes. In an equilibrium with purely vertical magnetic
field, the vertical magnetorotational modes are completely unaffected by
compressibility, stratification, and radiative diffusion. However, in the
presence of azimuthal fields, which are expected in differentially rotating
flows, the growth rate of all magnetorotational modes can be reduced
substantially below the orbital frequency. This occurs if diffusion destroys
radiation sound waves on the length scale of the instability, and the magnetic
energy density of the azimuthal component exceeds the non-radiative thermal
energy density. While sluggish in this case, the magnetorotational instability
still persists and will still tap the free energy of the differential rotation.
Photon bubble instabilities are generically present in radiation pressure
dominated flows where diffusion is present. We show that their growth rates are
limited to a maximum value which is reached at short wavelengths where the
modes may be viewed as unstable slow magnetosonic waves. We also find that
vertical radiation pressure destabilizes upward propagating fast waves, and
that Alfv\'en waves can be unstable. These instabilities typically have smaller
growth rates than the photon bubble/slow modes. We discuss how all these modes
behave in various regimes of interest, and speculate how they may affect the
dynamics of real accretion disk flows.

</DOC>
<DOC>
<DOCNO> 68451 </DOCNO>
Exploring the Ultrahigh Energy Neutrino Universe


  Astronomy at the highest energies observed must be performed by studying
neutrinos rather than photons because the universe is opaque to photons of
these energies. By making observations of neutrinos with energies above 10 EeV
one can deduce information about the distribution and cosmological history of
cosmic rays which may have been accelerated to energies above 100 EeV. Very
large fluxes of neutrinos at these energies which exhibit a hard spectrum would
be evidence of a GUT phase transition or superheavy dark matter particles.
Neutrinos at energies around a PeV may be produced in observable quantities in
active galaxies from the acceleration and interactions of cosmic rays in the
vicinity of massive black holes or in relativistic jets produced by these black
holes. Cosmological gamma-ray bursts may also produce PeV neutrinos. Neutrinos
at these energies may oscillate into tau neutrinos which can travel through the
Earth by the process of regeneration and produce upward moving air-showers.
Neutrinos of energies above of 1000 EeV can produce ultrahigh energy cosmic
rays thorugh interactions with big-bang neutrinos, producing Z bosons. This
"Z-burst" phenomenon can be used to study the mass and distribution of big-bang
neutrinos.

</DOC>
<DOC>
<DOCNO> 152177 </DOCNO>
Automorphisms as brane non-local transformations


  The relation among spacetime supersymmetry algebras and superbrane actions is
further explored. It is proved that $SL(2,\bR)$ belongs to the automorphism
group of the ${\cal N}=2$ D=10 type IIB SuperPoincar\'e algebra. Its SO(2)
subgroup is identified with a non-local SO(2) transformation found in
hep-th/9806161. Performing T-duality, new non-local transformations are found
in type IIA relating, among others, BIon configurations with two D2-branes
intersecting at a point. Its M-theory origin is explained. These results show
that part of the SuperPoincar\'e algebra automorphism group might be realized
on the field theory as non-local transformations.

</DOC>
<DOC>
<DOCNO> 121620 </DOCNO>
Chemical abundances and winds of massive stars in M31: a B-type


  We present high quality spectroscopic data for two massive stars in the OB10
association of M31, OB10-64 (B0Ia) and OB10-WR1 (WC6). Medium resolution
spectra of both stars were obtained using the ISIS spectrograph on the William
Hershel Telescope. This is supplemented with HST-STIS UV spectroscopy and KeckI
HIRES data for OB10-64. A non-LTE model atmosphere and abundance analysis for
OB10-64 is presented indicating that this star has similar photospheric CNO, Mg
and Si abundances as solar neighbourhood massive stars. A wind analysis of this
early B-type supergiant reveals a mass-loss rate of M_dot=1.6x10^-6
M_solar/yr,and v_infty=1650 km/s. The corresponding wind momentum is in good
agreement with the wind momentum -- luminosity relationship found for Galactic
early B supergiants. Observations of OB10W-R1 are analysed using a non-LTE,
line-blanketed code, to reveal approximate stellar parameters of log L/L_solar
\~ 5.7, T~75 kK, v_infty ~ 3000 km/s, M_dot ~ 10^-4.3 M_solar/yr, adopting a
clumped wind with a filling factor of 10%. Quantitative comparisons are made
with the Galactic WC6 star HD92809 (WR23) revealing that OB10-WR1 is 0.4 dex
more luminous, though it has a much lower C/He ratio (~0.1 versus 0.3 for
HD92809). Our study represents the first detailed, chemical model atmosphere
analysis for either a B-type supergiant or a WR star in Andromeda, and shows
the potential of how such studies can provide new information on the chemical
evolution of galaxies and the evolution of massive stars in the local Universe.

</DOC>
<DOC>
<DOCNO> 13962 </DOCNO>
Radio-frequency Bloch-transistor electrometer


  A quantum-limited electrometer based on charge modulation of the Josephson
supercurrent in the Bloch transistor inserted into a superconducting ring is
proposed. As this ring is inductive coupled to a high-Q resonance tank circuit,
the variations of the charge on the transistor island (input signal) are
converted into variations of amplitude and phase of radio-frequency
oscillations in the tank. These variations are amplified and then detected. The
output noise, the back-action fluctuations and their cross-correlation are
computed. It is shown that our device enables measurements of the charge with a
sensitivity which is determined by the energy resolution of its amplifier, that
can be reduced down to the standard quantum limit of \hbar/2. On the basis of
this setup a "back-action-evading" scheme of the charge measurements is
proposed.

</DOC>
<DOC>
<DOCNO> 40582 </DOCNO>
Review of Heavy-Quark Production at Fixed-Target Experiments


  An increasingly large amount of quality fixed-target data on heavy-quark
production at fixed-target energies is appearing. This data can provide
information across a range of physics topics. The topics vary from
investigations of QCD predictions to the understanding of the structure of
hadrons. Recent results on neutrino, photon, and hadron production of charm and
beauty will be reviewed in this context. The greatest insight will come from
combining multiple measurements as they relate to the physics topics, and by
ensuring that the parameters used in models are consistent with all the
measurements. We have not yet really entered the time when this has been done
for fixed-target measurements.

</DOC>
<DOC>
<DOCNO> 118895 </DOCNO>
The Relation Between Activity and Environment in Compact Groups of


  We present the results of the classification of spectral activity types for
193 galaxies from a new sample of 49 compact groups of galaxies in the southern
hemisphere (SCGs). This sample was selected in automated fashion from a
digitized galaxy catalogue, covering an area of ~5200 sq deg, around the South
Galactic Pole. It is complete up to m ~14.5 in b_j for the brightest galaxy of
the group.
  The spectral analysis of the SCG galaxies confirms the results previously
obtained for a smaller sample of Hickson's compact groups (HCG). We confirm the
luminosity-activity and morphology-activity relations, as well as the
predominance of AGNs (41% of SCGs galaxies). We verified also that the number
of early-type non-emission-line galaxies increases with the number of members
in the group.
  The SCGs contain more star-forming galaxies (SFGs) and less non-emission-line
galaxies than HCGs, which suggests that they probe a wider range of physical
properties. The SFGs are composed in majority of HII Nucleus Galaxies, which
have less intense star formation than starburst galaxies. The star formation
activity in SCGs is, consequently, remarkably low. The SFGs show also evidence
for nuclear activity. If these results are further confirmed, 70% of the
galaxies in SCGs would then have an active nucleus, making these systems
remarkably rich in AGNs. Curiously, however, this characteristic of CGs
generally excludes Seyfert 1 galaxies.(Abridged)

</DOC>
<DOC>
<DOCNO> 12812 </DOCNO>
Non-Equilibrium Duality


  The dual 'worldline', or 'string', description of adiabatic Ginzburg-Landau
field theory near a phase transition in terms of quasi-Brownian strings and
loops is well understood. In reality, the implementation of a transition is
intrinsically non-equilibrium. We sketch how time-dependent Ginzburg-Landau
theory leads to a modified dual string picture in which a causal bound on the
growth of unstable string prevents the uncontrolled proliferation of string
(the Shockley-Hagedorn transition) suggested by the adiabatic approximation.

</DOC>
<DOC>
<DOCNO> 12226 </DOCNO>
Validity of the zero-thermodynamic law in off-equilibrium coupled


  In order to describe the thermodynamics of the glassy systems it has been
recently introduced an extra parameter also called effective temperature which
generalizes the fluctuation-dissipation theorem (FDT) to systems
off-equilibrium and supposedly describes thermal fluctuations around the aging
state. Here we investigate the applicability of a zero-th law for
non-equilibrium glassy systems based on these effective temperatures by
studying two coupled subsystems of harmonic oscillators with Monte Carlo
dynamics. We analyze in detail two types of dynamics: 1) sequential dynamics
where the coupling between the subsystems comes only from the Hamiltonian and
2) parallel dynamics where there is a further coupling between the subsystems
arising from the dynamics. We show that the coupling described in the first
case is not enough to make asymptotically the effective temperatures of two
interacting subsystems coincide, the reason being the too small thermal
conductivity between them in the aging state. This explains why different
interacting degrees of freedom in structural glasses may stay at different
effective temperatures without never mutually thermalizing.

</DOC>
<DOC>
<DOCNO> 122201 </DOCNO>
The Accretion Ejection Instability : Observationnal Tests


  The Accretion Ejection Instability (hereafter AEI), has been proposed to
explain, the energy and angular momentum transport from the innermost parts of
accretion disks in the X-Ray Binaries (XB), (permitting thus the accretion),
toward a coronal medium, which is thought to be the base of jets (Tagger &
Pellat, 1999; Tagger 1999, Varni\`ere et al., 2000; Corbel, phD Thesis, 1999).
The low frequency QPO often observed in the XB's, are theorically predicted
with the AEI; furthemore theorical calculations in a strong gravitationnal
field (Varni\`ere, Rodriguez & Tagger, 2000) lead to an unexpected behavior
when looking at the QPO frequency variations vs. the disk radius. We the
analysed a set of public observations of GRO J1655-40 and GRS 1915+105, in
order to verify the theorical predictions. We 'll see in particular that they
have different behavior, and will point out interesting differences between the
two sources when the model gives unrealistic low values of the disk radius.

</DOC>
<DOC>
<DOCNO> 13529 </DOCNO>
Magneto-thermal instabilities in kappa-(BEDT-TTF)2Cu(NCS)2


  Angle and temperature dependent torque magnetization measurements are
reported for the organic superconductor kappa-(BEDT-TTF)2Cu(NCS)2, at extremely
low temperatures (approx. Tc/10^3). Magneto-thermal instabilities are observed
in the form of abrupt magnetization (flux) jumps. We carry out an analysis of
the temperature and field orientation dependence of these flux jumps based on
accepted models for layered type-II superconductors. Using a simple Bean model,
we also find a critical current density of 4x10^8 A/m^2 from the remnant
magnetization, in agreement with previous measurements.

</DOC>
<DOC>
<DOCNO> 99704 </DOCNO>
Lie Groups, Calabi-Yau Threefolds, and F-Theory


  The F-theory vacuum constructed from an elliptic Calabi-Yau threefold with
section yields an effective six-dimensional theory. The Lie algebra of the
gauge sector of this theory and its representation on the space of massless
hypermultiplets are shown to be determined by the intersection theory of the
homology of the Calabi-Yau threefold. (Similar statements hold for M-theory and
the type IIA string compactified on the threefold, where there is also a
dependence on the expectation values of the Ramond-Ramond fields.) We describe
general rules for computing the hypermultiplet spectrum of any F-theory vacuum,
including vacua with non-simply-laced gauge groups. The case of monodromy
acting on a curve of A_even singularities is shown to be particularly
interesting and leads to some unexpected rules for how 2-branes are allowed to
wrap certain 2-cycles. We also review the peculiar numerical predictions for
the geometry of elliptic Calabi-Yau threefolds with section which arise from
anomaly cancellation in six dimensions.

</DOC>
<DOC>
<DOCNO> 72325 </DOCNO>
QCD Confinement and Theta Vacuum: Dynamical Spontaneous Symmetry


  This study proposes that the longstanding problems of quantum chromodynamics
(QCD) as an SU(3)_C gauge theory, the confinement mechanism and \Theta vacuum,
can be resolved by dynamical spontaneous symmetry breaking (DSSB) through the
condensation of singlet gluons and quantum nucleardynamics (QND) as an SU(2)_N
x U(1)_Z gauge theory is produced. The confinement mechanism is the result of
massive gluons and the Yukawa potential provides hadron formation. The
evidences for the breaking of discrete symmetries (C, P, T, CP) during DSSB
appear explicitly: baryons and mesons without their parity partners, the
conservation of vector current and the partial conservation of the axial vector
current, the baryon asymmetry \delta_B \simeq 10^{-10}, and the neutron
electric dipole moment \Theta < 10^{-9}. Hadron mass generation mechanism is
suggested in terms of DSSB due to the \Theta vacuum.

</DOC>
<DOC>
<DOCNO> 122061 </DOCNO>
HI absorption and the ISM around radio galaxies


  We present a study, done with the Australian LBA, of HI absorption for two
compact radio galaxies (PKS 1549-79 and PKS 1814-63). In both the radio
galaxies, the HI appears to give us information about the environment in which
the radio sources are embedded, the effect that the ISM can have on the
observed characteristics and the possible presence of interaction between the
ISM and the radio plasma.

</DOC>
<DOC>
<DOCNO> 8879 </DOCNO>
Thermal diffusion of sine-Gordon solitons


  We analyze the diffusive motion of kink solitons governed by the thermal
sine-Gordon equation. We analytically calculate the correlation function of the
position of the kink center as well as the diffusion coefficient, both up to
second-order in temperature. We find that the kink behavior is very similar to
that obtained in the overdamped limit: There is a quadratic dependence on
temperature in the diffusion coefficient that comes from the interaction among
the kink and phonons, and the average value of the wave function increases with
$\sqrt{t}$ due to the variance of the centers of individual realizations and
not due to kink distortions. These analytical results are fully confirmed by
numerical simulations.

</DOC>
<DOC>
<DOCNO> 101395 </DOCNO>
Quantum Hall effect and noncommutative geometry


  We study magnetic Hamiltonians motivated by the quantum Hall effect (QHE)
reviewing the results of earlier papers [CHMM], [CHM], [MM]. We consider the
effect of a random or almost periodic potential added to a two dimensional
magnetic Hamiltonian in which a hyperbolic geometry term provides an effective
potential. Without the potential term these Hamiltonians are invariant under a
projective Fuchsian group action. We construct an analogue of the Connes-Kubo
formula for the Hall conductance, identifying it as a geometric invariant
associated to an algebra of observables. We modify the Fredholm modules defined
in [CHMM] in order to prove the integrality of the Hall conductance.

</DOC>
<DOC>
<DOCNO> 68311 </DOCNO>
Production of high-energy gravitinos during preheating


  We present a new technique for the calculation of helicity $\pm 1/2$
gravitino production during preheating. It is based on the equivalence between
goldstinos and helicity $\pm 1/2$ gravitinos at high energies. The problem is
thus reduced to the standard (Majorana) fermion production after inflation.
Comparison with the results obtained in the unitary gauge is also presented.

</DOC>
<DOC>
<DOCNO> 13885 </DOCNO>
A fast, primary Coulomb blockade thermometer


  We have measured the third derivative of the current-voltage characteristics,
d^3I/dV^3, in a two-dimensional array of small tunnel junctions using a lock-in
amplifier. We show that this derivative is zero at a voltage which scales
linearly with the temperature and depends only on the temperature and natural
constants, thus providing a primary thermometer. We demonstrate a measurement
method which extracts the zero crossing voltage directly using a feedback
circuit. This method requires only one voltage measurement, which makes it
substantially faster than the original Coulomb blockade thermometry method.

</DOC>
<DOC>
<DOCNO> 150634 </DOCNO>
Thermal Quantum Fields in Static Electromagnetic Backgrounds


  We present and discuss, at a general level, new mathematical results on the
spatial nonuniformity of thermal quantum fields coupled minimally to static
background electromagnetic potentials. Two distinct examples are worked through
in some detail: uniform (parallel and perpendicular) background electric and
magnetic fields coupled to a thermal quantum scalar field.

</DOC>
<DOC>
<DOCNO> 119694 </DOCNO>
The Small-scale Structure in Interstellar HI: A Resolvable Puzzle


  During the past decade or so, measurements of Galactic HI absorption using
VLBI against extra-galactic sources, as well as multi-epoch observatios in
pulsar directions, have detected small-scale transverse variations
corresponding to tens of AU at the distance of the absorbing matter. Hitherto
these measurements have been interpreted as small-scale structure in the HI
distribution with densities n_{HI} ~ 10^4-10^5 per cc, orders of magnitude
greater than those of the parsec-scale structure. Naturally it is difficult to
imagine how such structures could exist in equilibrium with other components of
the ISM.
  In this paper we show that structure on all scales contributes to the
differences on neighbouring lines of sight, and that the observed differences
can be accounted for by a natural extension of the distribution of
irregularities in the distribution of HI opacities at larger scales, using a
single power law. This, in our opinion, should put an end to the decades long
puzzle of the so-called small-scale structure in HI and other species in the
Galaxy.

</DOC>
<DOC>
<DOCNO> 71397 </DOCNO>
Cosmological Topology in Paris 1998


  Quel est, ou pourrait \^etre, la topologie globale de la partie spatiale de
l'Univers ? L'Univers entier (pr\'ecis\'ement, l'hypersurface spatiale de
celui-ci) est-il observable ? Les math\'ematiciens, les physiciens et les
cosmologistes observationnels ont des approches diff\'erentes pour aborder ces
questions qui restent ouvertes.
  What is, or could be, the global topology of spatial sections of the
Universe? Is the entire Universe (spatial hypersurface thereof) observable ?
Mathematicians, physicists and observational cosmologists have different
strategies to approaching these questions which are not yet fully answered.

</DOC>
<DOC>
<DOCNO> 40084 </DOCNO>
First Measurement of the Inclusive Branching Ratio of b Hadrons to phi


  The inclusive production rate of phi mesons from the decay of b hadrons
produced in Z0 decays was measured to be Br(b->phi+X) =
0.0282+-0.0013(stat.)+-0.0019(syst.), using data collected by the OPAL detector
at LEP.

</DOC>
<DOC>
<DOCNO> 84776 </DOCNO>
Fluids of Vortices And Dark Matter


  By considering full-field string solutions of the Abelian--Higgs model, we
modify the model of a fluid of strings (which is composed of Nambu strings) to
obtain a model for a ``fluid of vortices.'' With this model, and following
closely Soleng's proposal of a fluid of strings as the source of a Milgrom-type
correction to the Newton dynamics, we determine quantitatively the modified
dynamics generated by a static, spherical fluid of vortices.

</DOC>
<DOC>
<DOCNO> 118028 </DOCNO>
An Australia telescope survey for CMB anisotropies


  We have surveyed six distinct `empty fields' using the Australia Telescope
Compact Array in an ultra-compact configuration with the aim of imaging, with a
high brightness sensitivity, any arcmin-scale brightness-temperature
anisotropies in the background radio sky. The six well-separated regions were
observed at a frequency of 8.7 GHz and the survey regions were limited by the
ATCA primary beams which have a full width at half maximum of 6 arcmin at this
frequency; all fields were observed with a resolution of 2 arcmin and an rms
thermal noise of 24 microJy/beam. After subtracting foreground confusion
detected in higher resolution images of the fields, residual fluctuations in
Stokes I images are consistent with the expectations from thermal noise and
weaker (unidentified) foreground sources; the Stokes Q and U images are
consistent with expectations from thermal noise.
  Within the sensitivity of our observations, we have no reason to believe that
there are any Sunyaev-Zeldovich holes in the microwave sky surveyed. Assuming
Gaussian-form CMB anisotropy with a `flat' spectrum, we derive 95 per cent
confidence upper limits of Q_flat < 10--11 microK in polarized intensity and
Q_flat < 25 microK in total intensity. The ATCA filter function peaks at l=4700
and has half maximum values at l=3350 and 6050.

</DOC>
<DOC>
<DOCNO> 170506 </DOCNO>
Quantum mechanics with the permitted hidden parameters


  Within the framework of the algebraic approach the problem of hidden
parameters in quantum mechanics is surveyed. It is shown that the algebraic
formulation of quantum mechanics permits introduction of a specific hidden
parameter, which has the form of nonlinear functional on the algebra of
observables. It is found out that the reasoning of von Neumann and of Bell
about incompatibility of quantum mechanics with hidden parameters is
inapplicable to the present case.

</DOC>
<DOC>
<DOCNO> 99789 </DOCNO>
Surgeries on periodic links and homology of periodic 3-manifolds


  We show that a closed orientable 3-manifold M admits an action of Z_p with
fixed point set S^1 iff M can be obtained as the result of surgery on a
p-periodic framed link L and Z_p acts freely on the components of L. We prove a
similar theorem for free Z_p-actions. As an interesting application, we prove
the following, rather unexpected result: for any M as above and for any odd
prime p, H_1(M, Z_p)\ne Z_p. We also prove a similar criterion of 2-periodicity
for rational homology 3-spheres.

</DOC>
<DOC>
<DOCNO> 117074 </DOCNO>
Influence of guiding magnetic field on emission of stimulated photons in


  Effect of guiding magnetic field on evolution of stimulated emission is
considered. It is shown that the transverse dynamics of electrons contributes
to generation process and that contribution decreases with the magnetic field
grows. The equation of generation for stimulated radiation of electron beam
passing over periodic medium in magnetic field of arbitrary value is
derived. The critical value of guiding field for which the transverse dynamics
of electron don't contribute to emission is determined. It is shown, that
transverse dynamics of electron modifies the boundary conditions. It follows
from the derived generation equation that transverse dynamics yields to ~25%
increase of the increment magnitude in high gain regime. In the limit of small
signal the generation gain twice increases when transverse dynamics
evolves. Obtained results are valid for every FEL system, which use the
mechanism of waves slowing in the slow-wave structures for generation.

</DOC>
<DOC>
<DOCNO> 68687 </DOCNO>
Landau-Pomeranchuk-Migdal effect in thermal field theory


  In recent studies, the production rate of photons or lepton pairs by a quark
gluon plasma has been found to be enhanced due to collinear singularities. This
enhancement pattern is very dependent on rather strict collinearity conditions
between the photon and the quark momenta. It was estimated by neglecting the
collisional width of quasi-particles. In this paper, we study the modifications
of this collinear enhancement when we take into account the possibility for the
quarks to have a finite mean free path. Assuming a mean free path of order
$(g^2T\ln(1/g))^{-1}$, we find that only low invariant mass photons are
affected. The region where collision effects are important can be interpreted
as the region where the Landau-Pomeranchuk-Migdal effect plays a role in
thermal photon production by bremsstrahlung. It is found that this effect
modifies the spectrum of very energetic photons as well. Based on these results
and on a previous work on infrared singularities, we end this paper by a
reasonable physical picture for photon production by a quark gluon plasma, that
should be useful to set directions for future technical developments.

</DOC>
<DOC>
<DOCNO> 10275 </DOCNO>
The neutron resonance: modeling photoemission and tunneling data in the


  Motivated by neutron scattering data, we develop a model of electrons
interacting with a magnetic resonance and use it to analyze angle resolved
photoemission (ARPES) and tunneling data in the superconducting state of
Bi_2Sr_2CaCu_2O_{8+d}. We not only can explain the peak-dip-hump structure
observed near the (pi,0) point, and its particle-hole asymmetry as seen in SIN
tunneling spectra, but also its evolution throughout the Brillouin zone,
including a velocity `kink' near the d-wave node.

</DOC>
<DOC>
<DOCNO> 120879 </DOCNO>
RXTE observations of the Seyfert galaxy NGC 5506: evidence for


  We report on observations of the narrow line Seyfert galaxy NGC 5506 with the
Rossi X-ray TIming Explorer. The observations cover a time interval of ~1000
days during which the source showed strong flux and spectral variability. The
spectrum clearly shows iron fluorescence emission at 6.4 keV and significant
reflection features. Both the equivalent width of the iron line and the
relative strength of the reflected continuum are higher during low flux states.
The variability of the reflection features can be explained by the presence of
two reflected components: one that responds rapidly to flux changes of the
primary continuum and a second, slowly variable, component originating from a
distant reflector, e.g. a molecular torus.

</DOC>
<DOC>
<DOCNO> 8246 </DOCNO>
The algebraic structure of the Onsager algebra


  We study the Lie algebra structure of the Onsager algebra from the ideal
theoretic point of view. A structure theorem of ideals in the Onsager algebra
is obtained with the connection to the finite-dimensional representations. We
also discuss the solvable algebra aspect of the Onsager algebra through the
formal Lie algebra theory.

</DOC>
<DOC>
<DOCNO> 150894 </DOCNO>
SU(N) Skyrmions from Instantons


  Atiyah and Manton have outlined a scheme to obtain approximations to the
SU(2) skyrmions from instantons in $\R^4$. In this paper we apply this scheme
to construct, in an explicit form, approximations to static spherically
symmetric SU(N) skyrmions with various baryon numbers. In particular we show
how to obtain the skyrmions from instantons using harmonic maps into complex
projective spaces.

</DOC>
<DOC>
<DOCNO> 170475 </DOCNO>
Matter-wave entanglement and teleportation by molecular dissociation and


  We propose dissociation of cold diatomic molecules as a source of atom pairs
with highly correlated (entangled) positions and momenta, approximating the
original quantum state introduced by Einstein, Podolsky and Rosen (EPR) [Phys.
Rev. 47, 777 (1935)]. Wavepacket teleportation is shown to be achievable by its
collision with one of the EPR correlated atoms and manipulation of the other
atom in the pair.

</DOC>
<DOC>
<DOCNO> 100284 </DOCNO>
Gromov-Witten invariants of a class of toric varieties


  We describe the quantum cohomology rings of a class of toric varieties. The
description includes, in addition to the (already known) ring presentations,
the (new) analogues for toric varieties of the sorts of quantum Giambelli
formulas which exist already for Grassmannian varieties, flag varieties, etc.

</DOC>
<DOC>
<DOCNO> 71506 </DOCNO>
Three-Loop Leading Top Mass Contributions to the rho Parameter


  We present analytical results for the leading contributions of the top quark
to the electroweak rho parameter at order GF^3 Mt^6 and GF^2 Mt^4 alpha_s. The
Higgs boson and the gauge bosons are taken to be massless in this limit. The
correction of order GF^3 Mt^6 is found to be sizeable in comparison to the the
leading two-loop GF^2 Mt^4 correction, however it is much smaller than the
subleading GF^2 Mt^2 MZ^2 correction.

</DOC>
<DOC>
<DOCNO> 170087 </DOCNO>
Information gain versus disturbance for a single qubit


  I present an analytical derivation of the trade-off between the Shannon
information gain and the state disturbance for quantum operations performed on
a single qubit in an unknown pure state.

</DOC>
<DOC>
<DOCNO> 101425 </DOCNO>
Homotopy of vector states


  Let $B$ be a C$^*$-algebra and $X$ a C$^*$ Hilbert $B$-module. If $p\in B$ is
a projection, denote by $S_p =\{x\in X : < x,x> =p\}$, the $p$-sphere of $X$.
For $\phi$ a state of $B$ with support $p$ in $B$ and $x\in S_p$, consider the
state $\phi_x$ of $L_B(X)$ given by $\phi_x(t)= \phi(< x,t(x)>)$. In this paper
we study certain sets associated to these states, and examine their topologic
properties. As an application of these techniques, we prove that the space of
states of the hyperfinite II$_1$ factor $R_0$, with support equivalent to a
given projection $p\in R_0$, regarded with the norm topology (of the conjugate
space of $R_0$), has trivial homotopy groups of all orders.
  The same holds for the space $$ S_p(R_0)=\{v\in R_0:v^*v=p\}\subset R_0 $$ of
partial isometries with initial space $p$, regarded with the ultraweak
topology.

</DOC>
<DOC>
<DOCNO> 121454 </DOCNO>
High-latitude molecular clouds and near-by OB associations


  The Galactic distribution of the high-latitude molecular clouds is
considered. It is suggested that the majority of these clouds are clustered in
two large shells around the two closest OB associations, Per OB3/Cas-Tau and
Sco OB2. The most prominent shell of high-latitude clouds is centred around the
Per OB3/ Cas-Tau association which is also at the centre of the Gould's Belt.
However, the Per OB3/Cas-Tau group of high-latitude clouds appears as an
elliptical shell at nearly right angles to the plane of the Gould's Belt. Its
kinematic age (~10 Myr) is much smaller than the expansion age (~35 Myr) of the
ring of intertellar matter associated with the Gould's Belt. It is suggested
that while, as is generally understood, the larger expanding ring of gas
associated with the Gould's Belt was created by stellar winds and supernova
explosions of the more massive OB stars of the Per OB3/Cas-Tau association ~35
Myr ago, the Per OB3 shell of high-latitude clouds was formed from the
back-falling gas as it was swept up by a more recent supernova explosion of an
early B type star in Per OB3 ~10 Myr ago. More distant OB associations also
produce similar shells of clouds at large heights from the Galactic plane
having relatively smaller angular sizes due to their greater distances. These
can be seen as higher latitude extensions of cloud complexes at lower Galactic
latitudes as, for example, in the case of Vela OB2.

</DOC>
<DOC>
<DOCNO> 150902 </DOCNO>
The Effect of the Boundary Conditions in the Reformulation of QCD_4


  We discuss the phase structure of QCD_4 as a perturbative deformation of the
Topological Quantum Field Theory (TQFT). When we choose a special Maximal
Abelian gauge (MAG) as the gauge fixing, the TQFT sector is equivalent to a 2D
O(3) non-linear sigma model (NLSM). We consider the finite temperature case,
and investigate the effect of the boundary conditions and the phase structure
of the TQFT sector. It can have a deconfining phase under the twisted boundary
conditions. However, this phase is screened once pertubative parts are added.
We conclude that the information about the phase structure is encoded in the
U(1) background in the case of the MAG.

</DOC>
<DOC>
<DOCNO> 170153 </DOCNO>
Strongly focused light beams interacting with single atoms in free space


  We construct 3-D solutions of Maxwell's equations that describe Gaussian
light beams focused by a strong lens. We investigate the interaction of such
beams with single atoms in free space and the interplay between angular and
quantum properties of the scattered radiation. We compare the exact results
with those obtained with paraxial light beams and from a standard input-output
formalism. We put our results in the context of quantum information processing
with single atoms.

</DOC>
<DOC>
<DOCNO> 119264 </DOCNO>
A Good Long Look at the Black Hole Candidates LMC X-1 and LMC X-3


  We present results from 170ksec long RXTE observations of LMC X-1 and LMC
X-3, taken in 1996 December, where their spectra can be described by a disc
black body plus an additional soft (Gamma~2.8) high-energy power-law (detected
up to 50keV in LMC X-3). These observations, as well as archival ASCA
observations, constrain any narrow Fe line present in the spectra to have an
equivalent width <90eV, broad lines (~150eV EW, \sigma ~ 1keV) are permitted.
We also study the variability of LMC X-1. Its X-ray power spectral density
(PSD) is approximately f^{-1} between 10^{-3} and 0.3Hz with a rms variability
of ~7%. Above 5keV the PSD shows evidence of a break at f > 0.2Hz, possibly
indicating an outer disc radius of ~1000GM/c^2 in this likely wind-fed system.
Furthermore, the coherence function between variability in the > 5keV band and
variablity in the lower energy bands is extremely low. We discuss the
implications of these observations for the mechanisms.

</DOC>
<DOC>
<DOCNO> 102415 </DOCNO>
Hyperelliptic Prym Varieties and Integrable Systems


  We introduce two algebraic completely integrable analogues of the Mumford
systems which we call hyperelliptic Prym systems, because every hyperelliptic
Prym variety appears as a fiber of their momentum map. As an application we
show that the generic fiber of the momentum map of the periodic Volterra
lattice $$\dot a_i=a_i(a_{i-1}-a_{i+1}), \qquad i=1,...,n,\quad a_{n+1}=a_1,$$
is an affine part of a hyperelliptic Prym variety, obtained by removing $n$
translates of the theta divisor, and we conclude that this integrable system is
algebraic completely integrable.

</DOC>
<DOC>
<DOCNO> 8486 </DOCNO>
Order and Disorder Phenomena at Surfaces of Binary Alloys


  We present recent Monte Carlo results on surfaces of bcc-structured binary
alloys which undergo an order-disorder phase transformation in the bulk. In
particular, we discuss surface order and surface induced disorder at the bulk
transition between the ordered (DO3) phase and the disordered (A2) phase. An
intricate interplay between different ordering and segregation phenomena leads
to a complex surface behavior, which depends on the orientation of the surface
under consideration. abstract

</DOC>
<DOC>
<DOCNO> 70516 </DOCNO>
Synchrotron Production of Photons by a Two-body System


  The power spectrum of the synchrotron radiation generated by the motion of a
two-body charged system in an accelerator is derived in the framework of the
Schwinger source theory. The final formula can be used to verify the Lorentz
length contraction of the two-body system moving in the synchrotron.

</DOC>
<DOC>
<DOCNO> 84304 </DOCNO>
Macroscopic Einstein-Maxwell equations for a system of interacting


  In this paper the macroscopic Einstein and Maxwell equations for system, in
which the electromagnetic interactions are dominating (for instance, the
cosmological plasma before the moment of recombination), are derived. Ensemble
averaging of the microscopic Einstein - Maxwell equations and the iouville
equations for the random functions leads to a closed system of macroscopic
Einstein - Maxwell equations and kinetic equations for one-particle
distribution functions. The macroscopic Einstein equations for a relativistic
plasma differ from the classical Einstein equations in that their left-hand
sides contain additional terms due to particle interaction. The terms are
traceless tensors with zero divergence. An explicit covariant expression for
these terms is given in the form of momentum-space integrals of expressions
depending on one-particles distribution functions of the interacting particles
of the medium. The macroscopic Maxwell equations alsow differ from the
classical macroscopic Maxwell equations in that their left-hand sides contain
additional terms due to particle interaction as well the effects of general
relativity.

</DOC>
<DOC>
<DOCNO> 152392 </DOCNO>
Dyonic Integrable Models


  A class of non abelian affine Toda models arising from the axial gauged
two-loop WZW model is presented. Their zero curvature representation is
constructed in terms of a graded Kac-Moody algebra. It is shown that the
discrete multivacua structure of the potential together with non abelian nature
of the zero grade subalgebra allows soliton solutions with non trivial electric
and topological charges.
 The dressing transformation is employed to explicitly construct one and two
soliton solutions and their bound states in terms of the tau functions. A
discussion of the classical spectra of such solutions and the time delays are
given in detail.

</DOC>
<DOC>
<DOCNO> 117349 </DOCNO>
Physical Conditions, Grain Temperatures, and Enhanced Very Small Grains


  We derive the radio spectral index of the Barnard Loop (BL) from large-scale
radio surveys at four frequencies and find it to be a thermal source. We use
the radio data together with H-alpha data to determine the electron temperature
in BL, the lambda-Ori HII region, and a high-latitude filament; all of these
regions are somewhat cooler than typical HII regions.
  We perform least squares fits of the DIRBE diffuse IR intensities to the
21-cm line and radio continuum intensities. After the resolution of a
``geometrical conundrum'', this allows us to derive the electron density n_e;
we find n_e ~ 2.0 cm^{-3} and pressure (P/k) ~ 24000 cm^{-3} K.
  Grains within BL are warmer than in HI regions. Trapped L-alpha accounts for
the extra heating that is required. This is a general effect that needs to be
accounted for in all analyses that examine IR emission from H^+ regions. Very
small grains that emit 60 micron radiation are enhanced in BL relative to HI by
a factor of 2-3, while PAH's that emit 12 micron are probably deficient by a
factor ~2.

</DOC>
<DOC>
<DOCNO> 13563 </DOCNO>
Theory of Strongly Correlated Electron Systems. II.Intersite Coulomb


  The strong-coupling perturbation theory (SCPT) for correlated electron
systems is extended to the case of full Coulomb interaction. The Coulomb
mechanism of the orbital polarization is discussed and attention is paid to the
importance of spectral weight transfer between the localized and delocalized
subsystems of electrons. A one-to-one correspondence between subsets of Feynman
graphs of SCPT (which we name the approximation of renormalized Fermions (ARF))
and weak-coupling perturbation theory (WCPT) is established. The comparison of
the Galitskii and Migdal expression for the total energy and the Sham equation
(which connects the self-energy and the exchange-correlation potential in
density functional theory) for WCPT with the ones for the systems with strong
electron correlations is used for the formulation of a simple theory for
extending the local density approximation to density functional theory (DFT) to
include explicitly correlations. The extension requires the inclusion of the
many-electron spectral weights in the definition of the charge density and the
renormalization of the mixing and hopping matrix elements caused by many body
effects.

</DOC>
<DOC>
<DOCNO> 120805 </DOCNO>
Testing the Hypothesis of the Morphological Transformation from Field


  Hubble Space Telescope observations of distant clusters have suggested a
steep increase in the proportion of S0 galaxies between clusters at high
redshifts and similar systems the present-day. It has been proposed that this
increase results from the transformation of the morphologies of accreted field
galaxies from spirals to S0s. We have simulated the evolution of the
morphological mix in clusters based on a simple phenomenological model where
the clusters accrete a mix of galaxies from the surrounding field, the spiral
galaxies are transformed to S0s (through an unspecified process) and are added
to the existing cluster population. We find that in order to reproduce the
apparently rapid increase in the ratio of S0 galaxies to ellipticals in the
clusters, our model requires that: (1) galaxy accretion rate has to be high
(typically, more than half of the present-day cluster population must have been
accreted since z~0.5), and (2) most of the accreted spirals, with morphological
types as late as Scdm, must have transformed to S0's. Although the latter
requirement may be difficult to meet, it is possible that such bulge-weak
spirals have already been `pre-processed' into the bulge-strong galaxies prior
to entering the cluster core and are eventually transformed into S0's in the
cluster environment. On the basis of the evolution of the general morphological
mix in clusters our model suggests that the process responsible for the
morphological transformation takes a relatively long time (1-3Gyr) after the
galaxy has entered the cluster environment.

</DOC>
<DOC>
<DOCNO> 117668 </DOCNO>
Weak Lensing by High-Redshift Clusters of Galaxies - I: Cluster Mass


  We present the results of a weak lensing survey of six high-redshift (z >
0.5), X-ray selected clusters of galaxies. We have obtained ultra-deep R-band
images of each cluster with the Keck Telescope, and have measured a weak
lensing signal from each cluster. From the background galaxy ellipticities we
create two-dimensional maps of the surface mass density of each cluster. We
find that the substructure seen in the mass reconstructions typically agree
well with substructure in both the cluster galaxy distributions and X-ray
images of the clusters. We also measure the one-dimensional radial profiles of
the lensing signals and fit these with both isothermal spheres and "universal"
CDM profiles. We find that the more massive clusters are less compact and not
as well fit by isothermal spheres as the less massive clusters, possibly
indicating that they are still in the process of collapse.

</DOC>
<DOC>
<DOCNO> 14046 </DOCNO>
Evolutionary conservation of the folding nucleus


  In this Communication we present statistical analysis of conservation
profiles in families of homologous sequences for nine proteins whose folding
nucleus was determined by protein engineering methods. We show that in all but
one protein (AcP) folding nucleus residues are significantly more conserved
than the rest of the protein. Two aspects of our study are especially
important: 1) grouping of amino acids into classes according to their
physical-chemical properties and 2) proper normalization of amino acid
probabilities that reflects the fact that evolutionary pressure to conserve
some amino acid types may itself affect concentration of various amino acid
types in protein families. Neglect of any of those two factors may make
physical and biological ``signals'' from conservation profiles disappear.

</DOC>
<DOC>
<DOCNO> 178448 </DOCNO>
Shell Effects in Nuclei with Vector Self-Coupling of Omega Meson in


  Shell effects in nuclei about the stability line are investigated within the
framework of the Relativistic Hartree-Bogoliubov (RHB) theory with
self-consistent finite-range pairing. Using 2-neutron separation energies of Ni
and Sn isotopes, the role of $\sigma$- and $\omega$-meson couplings on the
shell effects in nuclei is examined. It is observed that the existing
successful nuclear forces (Lagrangian parameter sets) based upon the nonlinear
scalar coupling of $\sigma$-meson exhibit shell effects which are stronger than
suggested by the experimental data. We have introduced nonlinear vector
self-coupling of $\omega$-meson in the RHB theory. It is shown that the
inclusion of the vector self-coupling of $\omega$-meson in addition to the
nonlinear scalar coupling of $\sigma$-meson provides a good agreement with the
experimental data on shell effects in nuclei about the stability line. A
comparison of the shell effects in the RHB theory is made with the Hartree-Fock
Bogoliubov approach using the Skyrme force SkP. It is shown that the
oft-discussed shell quenching with SkP is not consistent with the available
experimental data.

</DOC>
<DOC>
<DOCNO> 40008 </DOCNO>
Ambiguity in source flux of high-energy cosmic neutrinos


  For high energy cosmic neutrinos Athar, Jezabek, and Yasuda (AJY) have
recently shown that the existing data on neutrino oscillations suggests that
cosmic neutrino flux at the AGN/GRB source, F(nu_e):F(nu_mu):F(nu_tau) approx
1:2:0, oscillates to F(nu_e):F(nu_mu):F(nu_tau) approx 1:1:1. These results can
be confirmed at AMANDA, Baikal, ANTARES and NESTOR, and other neutrino
detectors with a good flavor resolution. Here, we re-derive the AJY result from
quasi bi-maximal mixing, and show that observation of
F(nu_e):F(nu_\mu):F(nu_tau) approx 1:1:1 does not necessarily establish cosmic
neutrino flux at the AGN/GRB source to be F(nu_e):F(nu_mu):F(nu_tau) approx
1:2:0.

</DOC>
<DOC>
<DOCNO> 116242 </DOCNO>
The New Science of Complexity


  Deterministic chaos, and even maximum computational complexity, have been
discovered within Newtonian dynamics. Economists assume that prices and price
changes can also obey abstract mathematical laws of motion. Sociologists and
other postmodernists advertise that physics and chemistry have outgrown their
former limitations, that chaos and complexity provide new holistic paradigms
for science, and that the boundaries between the hard and soft sciences, once
impenetrable, have disappeared like the Berlin Wall. Three hundred years after
the deaths of Galileo, Descartes, and Kepler, and the birth of Newton,
reductionism appears to be on the decline, with holistic approaches to science
on the upswing. We therefore examine the evidence that dynamical laws of motion
may be discovered from empirical studies of chaotic or complex phenomena, and
also review the foundation of reductionism in invariance principle.

</DOC>
<DOC>
<DOCNO> 84144 </DOCNO>
On continued gravitational collapse


  According to a widespread idee fixe, the spherically-symmetric collapse of a
sufficiently massive celestial body of spherical shape should generate a black
hole. I prove that this process generates simply an ordinary point mass. My
argument is model-independent.

</DOC>
<DOC>
<DOCNO> 7826 </DOCNO>
Self-Consistent Effective-Medium Approximations with Path Integrals


  We study effective-medium approximations for linear composite media by means
of a path integral formalism with replicas. We show how to recover the
Bruggeman and Hori-Yonezawa effective-medium formulas. Using a replica-coupling
ansatz, these formulas are extended into new ones which have the same
percolation thresholds as that of the Bethe lattice and Potts model of
percolation, and critical exponents s=0 and t=2 in any space dimension d>= 2.
Like the Bruggeman and Hori-Yonezawa formulas, the new formulas are exact to
second order in the weak-contrast and dilute limits. The dimensional range of
validity of the four effective-medium formulas is discussed, and it is argued
that the new ones are of better relevance than the classical ones in dimensions
d=3,4 for systems obeying the Nodes-Links-Blobs picture, such as
random-resistor networks.

</DOC>
<DOC>
<DOCNO> 99315 </DOCNO>
Free Field Construction for the ABF Models in Regime II


  The Wakimoto construction for the quantum affine algebra U_q(\hat{sl}_2)
admits a reduction to the q-deformed parafermion algebras. We interpret the
latter theory as a free field realization of the Andrews-Baxter-Forrester
models in regime II. We give multi-particle form factors of some local
operators on the lattice and compute their scaling limit, where the models are
described by a massive field theory with Z_k symmetric minimal scattering
matrices.

</DOC>
<DOC>
<DOCNO> 72205 </DOCNO>
Gravitational Lorentz Violations and Adjustment of the Cosmological


  We investigate spacetimes in which the speed of light along flat 4D sections
varies over the extra dimensions due to different warp factors for the space
and the time coordinates (``asymmetrically warped'' spacetimes). The main
property of such spaces is that while the induced metric is flat, implying
Lorentz invariant particle physics on a brane, bulk gravitational effects will
cause apparent violations of Lorentz invariance and of causality from the brane
observer's point of view. An important experimentally verifiable consequence of
this is that gravitational waves may travel with a speed different from the
speed of light on the brane, and possibly even faster. We find the most general
spacetimes of this sort, which are given by AdS-Schwarzschild or
AdS-Reissner-Nordstrom black holes, assuming the simplest possible sources in
the bulk. Due to the gravitational Lorentz violations these models do not have
an ordinary Lorentz invariant effective description, and thus provide a
possible way around Weinberg's no-go theorem for the adjustment of the
cosmological constant. Indeed we show that the cosmological constant may relax
in such theories by the adjustment of the mass and the charge of the black
hole. The black hole singularity in these solutions can be protected by a
horizon, but the existence of a horizon requires some exotic energy densities
on the brane. We investigate the cosmological expansion of these models and
speculate that it may provide an explanation for the accelerating Universe,
provided that the timescale for the adjustment is shorter than the Hubble time.
In this case the accelerating Universe would be a manifestation of
gravitational Lorentz violations in extra dimensions.

</DOC>
<DOC>
<DOCNO> 11739 </DOCNO>
Some Exact Solutions For The Classical Hall Effect In Inhomogeneous


  The classical Hall effect in inhomogeneous systems is considered for the case
of one-dimensional inhomogeneity. For a certain geometry of the problem and for
the magnetic field linearly depending on the coordinate the density of current
distribution corresponds to the skin-effect.

</DOC>
<DOC>
<DOCNO> 11502 </DOCNO>
Convergence of Monte Carlo Simulations to Equilibrium


  We give two direct, elementary proofs that a Monte Carlo simulation converges
to equilibrium provided that appropriate conditions are satisfied. The first
proof requires detailed balance while the second is quite general.

</DOC>
<DOC>
<DOCNO> 120174 </DOCNO>
Mixed quark-nucleon phase in neutron stars and nuclear symmetry energy


  The influence of the nuclear symmetry energy on the formation of a mixed
quark-nucleon phase in neutron star cores is studied. We use simple
parametrizations of the nuclear matter equation of state, and the bag model for
the quark phase. The behavior of nucleon matter isobars, which is responsible
for the existence of the mixed phase, is investigated. The role of the nuclear
symmetry energy changes with the value of the bag constant B. For lower values
of B the properties of the mixed phase do not depend strongly on the symmetry
energy. For larger B we find that a critical pressure for the first quark
droplets to form is strongly dependent on the nuclear symmetry energy, but the
pressure at which last nucleons disappear is independent of it.

</DOC>
<DOC>
<DOCNO> 122343 </DOCNO>
OAO1657-415 : A `Missing Link' in High Mass X-ray Binaries?


  OAO1657-415 is only the seventh eclipsing X-ray pulsar known and therefore
has the potential to yield only the seventh mass of a neutron star in an X-ray
binary. Here we report photometric and spectroscopic observations of candidates
for the optical counterpart to the system and identify a B6V or B5III star as a
possible companion to the neutron star. We measure the observational parameters
of the star and suggest reasons why OAO1657-415 may be unlike other high mass
X-ray binaries.

</DOC>
<DOC>
<DOCNO> 99422 </DOCNO>
On a Planarity Criterion Coming from Knot Theory


  A graph G is called "minimalizable" if a diagram with minimal crossing number
can be obtained from an arbitrary diagram of G by crossing changes. If,
furthermore, the minimal diagram is unique up to crossing changes then G is
called "strongly minimalizable". In this article, it is explained how
minimalizability of a graph is related to its automorphism group and it is
shown that a graph is strongly minimalizable if the automorphism group is
trivial or isomorphic to a product of symmetric groups. Then, the treatment of
crossing number problems in graph theory by knot theoretical means is discussed
and, as an example, a planarity criterion for strongly minimalizable graphs is
given.

</DOC>
<DOC>
<DOCNO> 69525 </DOCNO>
A simple model illustrating the impossibility of measuring off-shell


  We consider a simple model and make use of field transformations in
Lagrangian field theories to illustrate the impossibility of measuring
off-shell effects in nucleon-nucleon bremsstrahlung and related processes.

</DOC>
<DOC>
<DOCNO> 12183 </DOCNO>
Quantum Fluctuations of a Nearly Critical Heisenberg Spin Glass


  We describe the interplay of quantum and thermal fluctuations in the
infinite-range Heisenberg spin glass. This model is generalized to SU(N)
symmetry, and we describe the phase diagram as a function of the spin S and the
temperature T. The model is solved in the large N limit and certain universal
critical properties are shown to hold to all orders in 1/N. For large S, the
ground state is a spin glass, but quantum effects are crucial in determining
the low T thermodynamics: we find a specific heat linear in T and a local
spectral density of spin excitations linear in frequency for a spin glass state
which is marginally stable to fluctuations in the replicon modes. For small S,
the spin-glass order is fragile, and a spin-liquid state dominates the
properties over a significant range of temperatures and frequencies. We argue
that the latter state may be relevant in understanding the properties of
strongly-disordered transition metal and rare earth compounds.

</DOC>
<DOC>
<DOCNO> 70780 </DOCNO>
Charged Particle Fluctuations as a Signal of the Dynamics of Heavy Ion


  Comparing proposed quantities to analyze charged particle fluctuations in
heavy ion experiments we find the dispersion of the charges in a central
rapidity box as best suited. Various energies and different nuclear sizes were
considered in an explicit Dual-Parton-Model calculation using the DPMJET code.
A definite deviation from predictions of recently considered statistical models
was obtained. Hence the charged particle fluctuations should provide a clear
signal of the dynamics of heavy ion processes. They should allow to directly
measure the degree of thermalization in a quantitative way.

</DOC>
<DOC>
<DOCNO> 9277 </DOCNO>
The phase diagram of quantum systems: Heisenberg antiferromagnets


  A novel approach for studying phase transitions in systems with quantum
degrees of freedom is discussed. Starting from the microscopic hamiltonian of a
quantum model, we first derive a set of exact differential equations for the
free energy and the correlation functions describing the effects of
fluctuations on the thermodynamics of the system. These equations reproduce the
full renormalization group structure in the neighborhood of a critical point
keeping, at the same time, full information on the non universal properties of
the model. As a concrete application we investigate the phase diagram of a
Heisenberg antiferromagnet in a staggered external magnetic field. At long
wavelengths the known relationship to the Quantum Non Linear Sigma Model
naturally emerges from our approach. By representing the two point function in
an approximate analytical form, we obtain a closed partial differential
equation which is then solved numerically. The results in three dimensions are
in good agreement with available Quantum Monte Carlo simulations and series
expansions. More refined approximations to the general framework presented here
and few applications to other models are briefly discussed.

</DOC>
<DOC>
<DOCNO> 118851 </DOCNO>
Cold dust in the starburst galaxy M82


  The starburst galaxy M82 has been mapped at 1.2 mm using the IRAM 30-m
telescope and the MPIfR 19-channel bolometer. The influence of the sidelobe
pattern and the 12CO(2-1) line has been carefully analyzed. Based on this
analysis, we conclude that the cold dust does not extend far into the halo as
has been previously claimed. The total mass of dust in the inner 3 kpc of the
galaxy is 7.5*10^6 M(sun). Assuming a solar gas-to-dust ratio, the inferred
total mass of gas is 7.5*10^8 M(sun).
  Unlike in any other galaxy we find the CO(2-1) line emission to be clearly
more extended than the 1.2 mm dust emission. A likely explanation for this
exceptional behaviour, seen for the first time in galaxies, is heating of
molecular gas by low-energy cosmic rays and soft X-rays in the halo of M82.

</DOC>
<DOC>
<DOCNO> 84851 </DOCNO>
Perturbation of junction condition and doubly gauge-invariant variables


  The junction condition across a singular surface in general relativity,
formulated by Israel, has double covariance. In this paper, a general
perturbation scheme of the junction condition around an arbitrary background is
given in a doubly covariant way. After that, as an application of the general
scheme, we consider perturbation of the junction condition around a background
with the symmetry of a $(D-2)$-dimensional constant curvature space, where $D$
is the dimensionality of the spacetime. The perturbed junction condition is
written in terms of doubly gauge-invariant variables only. Since the symmetric
background includes cosmological solutions in the brane-world as a special
case, the doubly gauge-invariant junction condition can be used as basic
equations for perturbations in the brane-world cosmology.

</DOC>
<DOC>
<DOCNO> 10568 </DOCNO>
Thermal expansion and the equation of state of Ir and Rh


  The simplest anharmonic characteristics of Ir and Rh are discussed in the
framework of a previously developed simple pseudopotential model which
describes the elastic moduli, phonon spectra and the lattice heat capacity in
the harmonic approximation of these metals succesfully. The microscopic
Gruneisen parameters, the dependences of the elastic moduli on pressure, the
coefficient of thermal expansion and the equations of state at the finite
temperatures have been calculated. The ab initio calculations of the
energy-band structure and the equation of state for Ir at T=0 have been done to
test the model for adequacy at high pressures. The values of different
contributions (zero-point oscillations, quasiharmonic, etc.) in the considered
thermodynamic characteristics of Ir and Rh are discussed.

</DOC>
<DOC>
<DOCNO> 85646 </DOCNO>
Gravitational waves in cosmological models of Ho\v{r}ava-Witten theory


  We study the behavior of gravitational waves and their backreaction on the
background in cosmological solutions of the five-dimensional Ho\v{r}ava-Witten
theory. As a dynamical background, we consider two cosmological solutions with
spatially flat expanding FRW branes, called $(\uparrow)$- and
$(\downarrow)$-solutions, in which the orbifold size increases and decreases in
time, respectively. % For these background solutions, the wave equation for the
tensor perturbation can be solved by the method of separation of variables, and
the mode functions are classified by a separation constant which can be
regarded as a graviton mass. We show that the spatial behavior of the mode
functions are the same for both background solutions, but the temporal behavior
is significantly different. We further show that for the $(\uparrow)$ solution,
the background bulk geometry is unstable against the backreaction of the
perturbation, while for the $(\downarrow)$ solution, the backreaction on the
bulk geometry can be neglected. We also show that, in contrast to the effect to
the bulk geometry, the backreaction of the perturbation significantly alters
the intrinsic geometry of the brane for the $(\downarrow)$ solution.

</DOC>
<DOC>
<DOCNO> 100900 </DOCNO>
Cardinal p and a theorem of Pelczynski


  We show that it is consistent that for some uncountable cardinal k, all
compactifications of the countable discrete space with remainders homeomorphic
to $D^k$ are homeomorphic to each other. On the other hand, there are $2^c$
pairwise non-homeomorphic compactifications of the countable discrete space
with remainders homeomorphic to $D^c$ (where c is the cardinality of the
continuum).

</DOC>
<DOC>
<DOCNO> 9771 </DOCNO>
Soliton dynamics in 1D quantum antiferromagnets


  The problem of dissipative motion of solitons in the case of tetramethyl
ammonium manganese chloride (TMMC) is studied as a function of the external
magnetic field and the temperature. Two specific situations are analyzed
separately; the first, above the transition temperature $T_N$, in which the
classical motion of the spin degree of freedom is described by a sine-Gordon
(SG) equation of motion and, the second, below $T_N$, in which the system is
described by a double sine-Gordon (2SG) equation of motion. The existence of a
dissipative regime for the soliton motion and its influence on the dynamical
structure factor -which might be experimentally detected- are reported.

</DOC>
<DOC>
<DOCNO> 170141 </DOCNO>
Multipartite generalisation of the Schmidt decomposition


  We find a canonical form for pure states of a general multipartite system, in
which the constraints on the coordinates (with respect to a factorisable
orthonormal basis) are simply that certain ones vanish and certain others are
real. For identical particles they are invariant under permutations of the
particles. As an application, we find the dimension of the generic local
equivalence class.

</DOC>
<DOC>
<DOCNO> 7740 </DOCNO>
The temperature dependent behaviour of surface states in ferromagnetic


  We present a model calculation for the temperature dependent behaviour of
surface states on a ferromagnetic local-moment film. The film is described
within the s-f model featuring local magnetic moments being exchange coupled to
the itinerant conduction electrons. The surface states are generated by
modifying the hopping in the vicinity of the surface of the film. In the
calculation for the temperature dependent behaviour of the surface states we
are able to reproduce both Stoner-like and spin-mixing behaviour in agreement
with recent (inverse) photoemission data on the temperature dependent behaviour
of a Gd(0001) surface state.

</DOC>
<DOC>
<DOCNO> 178779 </DOCNO>
Collective nature of $0^{+}$- states in deformed rare-earth nuclei


  The description of the energiy spectra of $0^{+}$ states for rare-earth
nuclei has been done involving the degree of the collectivity of corresponding
$0^{+}$-state as a systematics parameter. Holshtein-Primakoff representation
leads to very good agreement with experiment. Within the framework of this
approach the parameter of the collectivity is mainly determined by pairs of
particles constructed on single ''effective'' level. The results may be helpful
both for nuclear structure experimentalists and theorists in their
investigations of low-lying states structure and transition probabilities.

</DOC>
<DOC>
<DOCNO> 178827 </DOCNO>
$\pi \Delta\Delta$ coupling constant


  We calculate the $\pi \Delta\Delta$ coupling
$g_{\pi^0\Delta^{++}\Delta^{++}}$ using light cone QCD sum rule. Our result is
$g_{\pi^0\Delta^{++}\Delta^{++}}=(11.8\pm 2.0)$.

</DOC>
<DOC>
<DOCNO> 71469 </DOCNO>
Compton scattering in Noncommutative Space-Time at the NLC


  We study the Compton scattering in the noncommutative counter part of QED (NC
QED). Interactions in NC QED have momentum dependent phase factors and the
gauge fields have Yang Mills type couplings, this modifies the cross sections
and are different from the commuting Standard Model. Collider signals of
noncommutative space-time are studied at the Next Linear Collider (NLC)
operating in the $e \gamma$ mode. Results for different polarised cases are
presented and it is shown that the Compton process can probe the noncommutative
scale in the range of 1 - 2.5 TeV for typical proposed NLC energies.

</DOC>
<DOC>
<DOCNO> 69221 </DOCNO>
The radiative decay phi - gamma pi pi in a coupled channel model and the


  A coupled channel model is used to study the nature of the scalar mesons
produced in the decay phi - gamma pi pi. The KKbar molecular picture of f0(980)
is found to be in a good agreement with the recent experimental data from SND
and CMD-2. The structure of the light scalar mesons is elucidated by
investigating the S-matrix poles and the qqbar spectral density.

</DOC>
<DOC>
<DOCNO> 99463 </DOCNO>
Some boundedness results for Fano-like Moishezon manifolds


  We prove finiteness of the number of smooth blow-downs on Fano manifolds and
boundedness results for the geometry of non projective Fano-like manifolds. Our
proofs use properness of Hilbert schemes and Mori theory.

</DOC>
<DOC>
<DOCNO> 151381 </DOCNO>
Lattice Bosons


  Fermions on the lattice have bosonic excitations generated from the
underlying periodic background. These, the lattice bosons, arise near the empty
band or when the bands are nearly full. They do not depend on the nature of the
interactions and exist for any fermion-fermion coupling. We discuss these
lattice boson solutions for the Dirac Hamiltonian.

</DOC>
<DOC>
<DOCNO> 122365 </DOCNO>
Stellar Collisions and Mergers in the Galactic Center


  Stars are most likely to merge or collide in regions of the highest stellar
densities, and our own Galactic Center contains many stars packed into a
relatively small volume -- even the ambient stellar number density in the
central 50 pc is quite high, ~10^3 stars pc^{-3}. More striking, the three
compact young clusters in this region have central densities as high as 10^6
stars pc^{-3}. We discuss these extreme environments and the possibility that
stellar mergers and collisions have recently occured there. In particular, we
predict that at least one massive star in the Arches cluster has already
experienced a stellar merger in its short lifetime. Further, the Pistol Star,
in the nearby Quintuplet cluster, might owe its apparent relative youth to a
rejuvinating stellar merger. Finally, the apparently young stars in the central
arcsecond could be products of either collisions, inducing atmospheric
stripping, or mergers.

</DOC>
<DOC>
<DOCNO> 69512 </DOCNO>
Additional Isospin-Breaking Effects in epsilon'/epsilon


  Isospin-breaking effects, in particular those associated with
electroweak-penguin contributions and pi0-eta,eta' mixing, have long been known
to affect the Standard Model prediction of Re(epsilon'/epsilon) in a
significant manner. We have found an heretofore unconsidered isospin-violating
effect of importance; namely, the u-d quark mass difference can spawn |Delta
I|=3/2 components in the matrix elements of the gluonic penguin operators.
Using chiral perturbation theory and the factorization approximation for the
hadronic matrix elements, we find within a specific model for the low-energy
constants that we can readily accommodate an increase in Re(epsilon'/epsilon)
by a factor of two.

</DOC>
<DOC>
<DOCNO> 152627 </DOCNO>
Examples of stationary BPS solutions in N=2 supergravity theories with


  We discuss explicit examples of BPS solutions in four-dimensional N=2
supergravity with R^2-interactions. We demonstrate how to construct solutions
by iteration. Generically, the presence of higher-curvature interactions leads
to non-static spacetime line elements. We comment on the existence of horizons
for multi-centered solutions.

</DOC>
<DOC>
<DOCNO> 14068 </DOCNO>
Asymptotic behaviour for critical slowing-down random walks


  The jump processes W(t) on [0,\infty[ with transitions w -> alpha w at rate
b*w^beta (0 =< alpha =< 1, b>0, beta>0) are considered. Their moments are shown
to decay not faster than algebraically for t -> \infty, and an equilibrium
probability density is found for a rescaled process U = (t + k)^{-beta} W. A
corresponding birth process is discussed.

</DOC>
<DOC>
<DOCNO> 117695 </DOCNO>
Chemical enrichment and star formation in the Milky Way disk; II. Star


  A chromospheric age distribution of 552 late-type dwarfs is transformed into
a star formation history by the application of scale height corrections,
stellar evolutionary corrections and volume corrections. We show that the disk
of our Galaxy has experienced enhanced episodes of star formation at 0-1 Gyr,
2-5 Gyr and 7-9 Gyr ago, although the reality of the latter burst is still
uncertain. The star sample birthsites are distributed over a very large range
of distances because of orbital diffusion, and so give an estimate of the
global star formation rate. These results are compared with the
metal-enrichment rate, given by the age-metallicity relation, with the expected
epochs of close encounters between our Galaxy and the Magellanic Clouds, and
with previous determinations of the star formation history. Simulations are
used to examine the age-dependent smearing of the star formation history due to
age uncertainties, and the broadening of the recovered features, as well as to
measure the probability level that the history derived to be produced by
statistical fluctuations of a constant star formation history. We show with
more than 98% level of confidence that the the star formation of our Galaxy was
not constant.

</DOC>
<DOC>
<DOCNO> 117672 </DOCNO>
X-ray Surveys of the obscured Universe


  Deep X-ray surveys have shown that the cosmic X-ray background (XRB) is
largely due to accretion onto supermassive black holes, integrated over cosmic
time. However, the characteristic hard spectrum of the XRB can only be
explained if most AGN spectra are heavily absorbed. The absorbed AGN will
suffer severe extinction and therefore, unlike classical QSOs, will not be
prominent at optical wavelengths. Most of the accretion power is being absorbed
by gas and dust and will have to be reradiated in the FIR/sub-mm band. AGN
could therefore contribute a substantial fraction to the recently discovered
cosmic FIR/sub-mm background. Here it is shown that a number of high-redshift
absorbed X-ray sources selected in the ROSAT Deep Survey of the Lockman Hole
have broad-band spectral energy distributions very similar to the local ULIRG
NGC6240, lending additional support to the background models for the obscured
universe.

</DOC>
<DOC>
<DOCNO> 118574 </DOCNO>
2dF QSO Redshift Survey


  With approximately 6000 QSO redshifts,the 2dF QSO redshift survey is already
the biggest complete QSO survey. The aim for the survey is to have 25000 QSO
redshifts, providing an order of magnitude increase in QSO clustering
statistics. We first describe the observational parameters of the 2dF QSO
survey. We then describe several highlights of the survey so far, including new
estimates of the QSO luminosity function and its evolution. We also review the
current status of QSO clustering analyses from the 2dF data. Finally, we
discuss how the complete QSO survey will be able to constrain the value of
Omega_o by measuring the evolution of QSO clustering, place limits on the
cosmological constant via a direct geometrical test and determine the form of
the fluctuation power-spectrum out to the approximately 1000 Mpc scales only
previously probed by COBE.

</DOC>
<DOC>
<DOCNO> 117791 </DOCNO>
The Impact of Nuclear Reaction Rate Uncertainties on Evolutionary


  The observable consequences of a nova outburst depend sensitively on the
details of the thermonuclear runaway which initiates the outburst. One of the
more important sources of uncertainty is the nuclear reaction data used as
input for the evolutionary calculations. A recent paper by Starrfield, Truran,
Wiescher, & Sparks (1998) has demonstrated that changes in the reaction rate
library used within a nova simulation have significant effects, not just on the
production of individual isotopes (which can change by an order of magnitude),
but on global observables such as the peak luminosity and the amount of mass
ejected. We present preliminary results of systematic analyses of the impact of
reaction rate uncertainties on nova nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 118225 </DOCNO>
E+A galaxies in the near-IR: Broad band photometry


  (Abridged) We present near-IR photometry of a selected sample of southern
hemisphere E+A galaxies. The sample includes 50 galaxies from nearby and
distant clusters as well as E+A galaxies from the field. The photometry
includes J, H and Ks apparent magnitudes and colors. Observed colors are
obtained from the apparent total magnitudes and compared to spectrophotometric
models of galaxy evolution GISSEL96. There is an overall agreement between
integrated colors of models and observed ones, for both the E+A located in
clusters and in the field, at z~0.1. However, large differences are found
between colors predicted from models and those observed in E+A galaxies located
in more distant clusters. We investigate systematic properties of the E+A
sample as a function of their environment. Results seem to indicate that
cluster E+As (at low redshift) are bluer than field E+As at z~0.1. Even this
conclusion does not depend whether we use comoving or rest-frame colors, nor on
the models used to obtain rest-frame colors; the difference is not significant
enough, considering color dispersions between the samples. If differences are
real, they could imply different stellar content for the E+A galaxies located
in the field, compared to the cluster E+A.

</DOC>
<DOC>
<DOCNO> 13018 </DOCNO>
Critical exponents of the random-field O(N) model


  The critical behavior of the random-field Ising model has been a puzzle for a
long time. Different theoretical methods predict that the critical exponents of
the random-field ferromagnet in D dimensions are the same as in the pure
(D-2)-dimensional ferromagnet with the same number of the magnetization
components. This result contradicts the experiments and simulations. We
calculate the critical exponents of the random-field O(N) model with the
(4+\epsilon)-expansion and obtain values different from the critical exponents
of the pure ferromagnet in 2+\epsilon dimensions. In contrast to the previous
approaches we take into account an infinite set of relevant operators emerging
in the problem. We demonstrate how these previously missed relevant operators
lead to the breakdown of the (6-\epsilon)-expansion for the random-field Ising
model.

</DOC>
<DOC>
<DOCNO> 10933 </DOCNO>
Spin Domains Generate Hierarchical Ground State Structure in J=+/-1 Spin


  Unbiased samples of ground states were generated for the short-range Ising
spin glass with Jij=+/-1, in three dimensions. Clustering the ground states
revealed their hierarchical structure, which is explained by correlated spin
domains, serving as cores for macroscopic zero energy "excitations".

</DOC>
<DOC>
<DOCNO> 12487 </DOCNO>
AC Driven Jumps Distribution on a Periodic Substrate


  A driven Brownian particle (e.g. an adatom on a surface) diffusing on a
low-viscosity, periodic substrate may execute multiple jumps. In the presence
of an additional periodic drive, the jump lengths and time durations become
statistically modulated according to a syncronyzation mechanism reminiscent of
asymmetric stochastic resonance. Here, too, bistability plays a key role, but
in a dynamical sense, inasmuch as a particle switches between locked and
running states.

</DOC>
<DOC>
<DOCNO> 13196 </DOCNO>
Effect of a rigid nonpolar solute on the splay, bend elastic constants


  The effect of a rigid nonpolar non-mesogenic solute, ``biphenyl'' which is
(C_{6}H_{5}-C_{6}H_{5}), on the splay and bend elastic constants and on the
rotational viscosity coefficient of (4,4^{\prime})-n-octyl-cyano biphenyl (8CB)
is reported. The experiments involve the measurement of voltage dependence of
capacitance of a cell filled with the mixture. Anomalous behavior of both
(K_{11}) and (\Delta \epsilon) near the (N-S_{A}) transition have been
observed.

</DOC>
<DOC>
<DOCNO> 119786 </DOCNO>
Detecting Ultra High Energy Neutrinos by Upward Tau Airshowers and Gamma


  Tau Air-showers are the best trace of rarest Ultra High Energy neutrinos UHE
$\nu_{\tau}$, $\bar\nu_{\tau}$ and $\bar{\nu}_e$ at PeV and higher energy.
$\tau$ Air-showers may generate billion times amplified signals by their
secondaries . Horizontal amplified $\tau$ air-showers by $\nu_{\tau} N$ and UHE
$\bar\nu_{e} e$ at PeV emerging from mountain chain might be the most
power-full imprint. Upward UHE $\nu_{\tau} N$ interaction on Earth crust at
horizontal edge and from below, their consequent UHE $\tau$ air-showers beaming
toward high mountains should flash $\gamma$,$\mu$,X and optical detectors on
the top.
  Upward $\tau$ air-shower may hit nearby satellite flashing them by short,
hard, diluted $\gamma-$burst at the edge of Gamma Ray Observatory BATSE
threshold. We identify these events with recent (1994) discovered upward
Terrestrial Gamma Flashes (TGF) and we probed their UHE $\tau$ - UHE $\nu_\tau$
origin. From these TGF data approximated UHE $\nu_\tau$ flux and $\Delta
m_{\nu_\mu \nu_\tau}$ sever lower bound are derived. Partial TGF Galactic
signature is also manifest within known 47 TGF events clustered within three
degrees from the Galactic plane at ${\simeq 2\cdot 10^{-3}}$probability. Well
known $X-\gamma-\mathrm{TeV}$ active galactic and extragalactic sources have
found probable counterpart in TGF arrival directions. Detection of elusive UHE
$\nu_\tau$ seem finally achieved.

</DOC>
<DOC>
<DOCNO> 100661 </DOCNO>
Space-Time Invariant Measures, Entropy, and Dimension for Stochastic


  We consider a randomly forced Ginzburg-Landau equation on an unbounded
domain. The forcing is smooth and homogeneous in space and white noise in time.
We prove existence and smoothness of solutions, existence of an invariant
measure for the corresponding Markov process and we define the spatial
densities of topological entropy, of measure-theoretic entropy, and of upper
box-counting dimension. We prove inequalities relating these different
quantities. The proof of existence of an invariant measure uses the compact
embedding of some space of uniformly smooth functions into the space of locally
square-integrable functions and a priori bounds on the semi-flow in these
spaces. The bounds on the entropy follow from spatially localised estimates on
the rate of divergence of nearby orbits and on the smoothing effect of the
evolution.

</DOC>
<DOC>
<DOCNO> 116533 </DOCNO>
The propensity of molecules to spatially align in intense light fields


  The propensity of molecules to spatially align along the polarization vector
of intense, pulsed light fields is related to readily-accessible parameters
(molecular polarizabilities, moment of inertia, peak intensity of the light and
its pulse duration). Predictions can now be made of which molecules can be
spatially aligned, and under what circumstances, upon irradiation by intense
light. Accounting for both enhanced ionization and hyperpolarizability, it is
shown that {\it all} molecules can be aligned, even those with the smallest
static polarizability, when subjected to the shortest available laser pulses
(of sufficient intensity).

</DOC>
<DOC>
<DOCNO> 178527 </DOCNO>
Relativistic predictions of quasielastic proton-nucleus spin observables


  Within the framework of the relativistic plane wave impulse approximation
(RPWIA), complete sets of quasielastic $(\vec{p}, \vec{p}^{'})$ and $(\vec{p},
\vec{n})$ spin observables are calculated employing a general Lorentz invariant
representation of the NN scattering matrix (referred to as the IA2
representation). The use of a complete representation eliminates the
arbitrariness of a previously-used five-term parameterization (commonly called
the IA1 representation) and allows for the correct incorporation of
effective-mass-type medium effects within the RPWIA framework and within the
context of the Walecka model. For quasielastic scattering from a $^{40}$Ca
target at incident proton energies between 200 and 500 MeV, we investigate the
sensitivity of complete sets of spin observables to effective nucleon masses
for both IA1 and IA2 representations. In general it is seen that the IA1
representation may overestimate the importance of nuclear medium effects,
whereas the IA2-based predictions nearly correspond to values for free
nucleon-nucleon scattering.

</DOC>
<DOC>
<DOCNO> 169921 </DOCNO>
Quantum Games


  In these lecture notes we investigate the implications of the identification
of strategies with quantum operations in game theory beyond the results
presented in [J. Eisert, M. Wilkens, and M. Lewenstein, Phys. Rev. Lett. 83,
3077 (1999)]. After introducing a general framework, we study quantum games
with a classical analogue in order to flesh out the peculiarities of game
theoretical settings in the quantum domain. Special emphasis is given to a
detailed investigation of different sets of quantum strategies.

</DOC>
<DOC>
<DOCNO> 116868 </DOCNO>
High-Power Testing of the APT Power Coupler


  For the baseline APT (Accelerator Production of Tritium) linac design, power
couplers are required to transmit 210-kW of CW RF power to the superconducting
cavities. These APT couplers operate at 700 MHz, have a coaxial design and an
adjustable coupling to the superconducting cavities. Since May 1999, we have
been testing couplers of this design on a room-temperature test stand. We
completed tests at transmitted-power and reflected-power conditions up to 1 MW.
We also tested the couplers with a portion of the outer conductor cooled by
liquid nitrogen. Under this latter condition, we studied the effects of
condensed gases on coupler performance. The results of these tests indicate
that the APT couplers are capable of delivering more than 500 kW to the
cavities. We are in the process of increasing the baseline coupler design
requirement to 420 kW of transmitted power to take advantage of this successful
development. In this paper, we describe the results of our high-power coupler
tests.

</DOC>
<DOC>
<DOCNO> 13967 </DOCNO>
The effects of electron-electron interactions on the spin transport


  Spin transport properties of a spin-polarized two-dimensional electron gas
are studied in the presence of electron-electron interactions. Longitudinal and
transverse spin diffusion coefficients are calculated with the quantum
transport equation which includes many-particle effects in the random phase
approximation. We find that the $e$-$e$ scattering, which does not contribute
to charge drift mobility, has a significant contribution to the spin diffusion.
Thus, $e$-$e$ interaction causes non-negligible effects on the operations of
proposed devices dependent on spin transport in semiconductor heterostructures.

</DOC>
<DOC>
<DOCNO> 8022 </DOCNO>
Quasiparticle Spectrum of d-wave Superconductors in the Mixed State


  The quasiparticle spectrum of a two-dimensional d-wave superconductor in the
mixed state, H_{c1} << H << H_{c2}, is studied both analytically and
numerically using the linearized Bogoliubov-de Gennes equation. We consider
various values of the "anisotropy ratio" v_F/v_Delta for the quasiparticle
velocities at the Dirac points, and we examine the implications of symmetry.
For a Bravais lattice of vortices, we find there is always an isolated
energy-zero (Dirac point) at the center of the Brillouin zone, but for a
non-Bravais lattice with two vortices per unit cell there is generally an
energy gap. In both of these cases, the density of states should vanish at zero
energy, in contrast with the semiclassical prediction of a constant density of
states, though the latter may hold down to very low energies for large
anisotropy ratios. This result is closely related to the particle-hole symmetry
of the band structures in lattices with two vortices per unit cell. More
complicated non-Bravais vortex lattice configurations with at least four
vortices per unit cell can break the particle-hole symmetry of the linearized
energy spectrum and lead to a finite density of states at zero energy.

</DOC>
<DOC>
<DOCNO> 10847 </DOCNO>
Chiral Spin Liquids and Quantum Error Correcting Codes


  The possibility of using the two-fold topological degeneracy of spin-1/2
chiral spin liquid states on the torus to construct quantum error correcting
codes is investigated. It is shown that codes constructed using these states on
finite periodic lattices do not meet the necessary and sufficient conditions
for correcting even a single qubit error with perfect fidelity. However, for
large enough lattice sizes these conditions are approximately satisfied, and
the resulting codes may therefore be viewed as approximate quantum error
correcting codes.

</DOC>
<DOC>
<DOCNO> 120389 </DOCNO>
Power Spectrum Analysis of the ESP Galaxy Redshift Survey


  We measure the power spectrum of the galaxy distribution in the ESO Slice
Project (ESP) galaxy redshift survey. We develope a technique to describe the
survey window function analytically, and then deconvolve it from the measured
power spectrum using a variant of the Lucy method. We test the whole
deconvolution procedure on ESP mock catalogues drawn from large N-body
simulations, and find that it is reliable for recovering the correct amplitude
and shape of $P(k)$ at $k> 0.065 h$ Mpc$^{-1}$. In general, the technique is
applicable to any survey composed by a collection of circular fields with
arbitrary pattern on the sky, as typical of surveys based on fibre
spectrographs. The estimated power spectrum has a well-defined power-law shape
$k^n$ with $n\simeq -2.2$ for $k\ge 0.2 h$ Mpc$^{-1}$, and a smooth bend to a
flatter shape ($n\simeq -1.6$) for smaller $k$'s. The smallest wavenumber,
where a meaningful reconstruction can be performed ($k\sim 0.06 h$ Mpc$^{-1}$),
does not allow us to explore the range of scales where other power spectra seem
to show a flattening and hints for a turnover. We also find, by direct
comparison of the Fourier transforms, that the estimate of the two-point
correlation function $\xi(s)$ is much less sensitive to the effect of a
problematic window function as that of the ESP, than the power spectrum.
Comparison to other surveys shows an excellent agreement with estimates from
blue-selected surveys. In particular, the ESP power spectrum is virtually
indistinguishable from that of the Durham-UKST survey over the common range of
$k$'s, an indirect confirmation of the quality of the deconvolution technique
applied.

</DOC>
<DOC>
<DOCNO> 121011 </DOCNO>
Discovery of a new, third kHz QPO in 4U 1608-52, 4U 1728-34, and 4U


  We report the discovery of a third kilohertz quasi-periodic oscillation (kHz
QPO) in the power spectra of the low-mass X-ray binaries 4U 1608-52 (6.3
sigma), 4U 1728-34 (6.0 sigma), and 4U 1636-53 (3.7 sigma) which is present
simultaneously with the previously-known kHz QPO pair. The new kHz QPO is found
at a frequency that is 52.8+-0.9 Hz, 64+-2 Hz, 58.4+-1.9 Hz higher than the
frequency of the lower kHz QPO in 4U 1608-52, 4U 1728-34, and 4U 1636-53,
respectively. The difference between the frequency of the new kHz QPO and the
lower kHz QPO increased in 4U 1608-52 from 49.6+-1.4 Hz to 53.9+-0.5 Hz when
the frequency of the lower kHz QPO increased from 672 Hz to 806 Hz.
Simultaneously the difference between the frequency of the new kHz QPO and the
upper kHz QPO increased by ~60 Hz, suggesting that the new kHz QPO is unrelated
to the upper kHz QPO. In 4U 1636-53 a fourth, weaker, kHz QPO is simultaneously
detected (3 sigma) at the same frequency separation below the lower kHz QPO,
suggesting the new kHz QPOs are sidebands to the lower kHz QPO. We discuss the
nature of this new kHz QPO and its implications on the models for the kHz QPOs.

</DOC>
<DOC>
<DOCNO> 170394 </DOCNO>
A General Argument Against the Universal Validity of the Superposition


  We reconsider a well known problem of quantum theory, i.e. the so called
measurement (or macro-objectification) problem, and we rederive the fact that
it gives rise to serious problems of interpretation. The novelty of our
approach derives from the fact that the relevant conclusion is obtained in a
completely general way, in particular, without resorting to any of the
assumptions of ideality which are usually done for the measurement process. The
generality and unescapability of our assumptions (we take into account possible
malfunctionings of the apparatus, its unavoidable entanglement with the
environmment, its high but not absolute reliability, its fundamentally
uncontrollable features) allow to draw the conclusion that the very possibility
of performing measurements on a microsystem combined with the assumed general
validity of the linear nature of quantum evolution leads to a fundamental
contradiction.

</DOC>
<DOC>
<DOCNO> 67724 </DOCNO>
Unification through extra dimensions at two loops


  The presence of an extra dimension of size R\equiv M_c^{-1} introduces
corrections of order (\mu/M_c)\alpha to the gauge and Yukawa couplings and
accelerates their running at scales \mu larger than M_c. This could result in a
grand unification scale M_X\approx 20 M_c. We study the corrections at the
two-loop level. We find corrections of order (\mu/M_c)\alpha^2 for the gauge
couplings and of order (\mu/M_c)^2\alpha^2 for the Yukawa couplings. Therefore,
in the Yukawa sector one and two-loop contributions can be of the same order
below M_X. We show that in the usual scenarios the dominant gauge and Yukawa
couplings are decreasing functions of the scale, in such a way that
(\mu/M_c)\alpha becomes approximately constant and two-loop contributions
introduce just a 30% correction which does not increase with the scale.

</DOC>
<DOC>
<DOCNO> 117121 </DOCNO>
On the quantum aspects of the logarithmic corrections to the black hole


  A new relativity theory, or more concretely an extended relativity theory,
actively developed by one of the authors incorporates 3 basic concepts. They
are the old idea of Chew about bootstrapping, Nottale's scale relativity, and
enlargement of the conventional time-space by inclusion of noncommutative
Clifford manifolds where all p-branes are treated on equal footing. The latter
allows one to write a master action functional. The resulting functional
equation is simplified and applied to the p-loop oscillator. Its solution
represents a generalization of the conventional quantum point oscillator. In
addition, it exhibits some novel features: an emergence of two explicit scales
delineating the asymptotic regimes (Planck scale region and a smooth region of
a quantum point oscillator). In the most interesting Planck scale regime, the
solution recovers in an elementary fashion some basic relations of string
theory (including string tension quantization and string uncertainty relation).
It is shown that the degeneracy of the $first$ collective excited state of the
p-loop oscillator yields not only the well-known Bekenstein-Hawking
area-entropy linear relation but also the logarithmic corrections therein. In
addition we obtain for any number of dimensions the Hawking temperature, the
Schwarschild radius, and the inequalities governing the area of a black hole
formed in a fusion of two black holes. One of the interesting results is a
demonstration that the evaporation of a black hole is limited by the upper
bound on its temperature, the Planck temperature.

</DOC>
<DOC>
<DOCNO> 99885 </DOCNO>
Quantization of certain skew-symmetric solutions of the classical


  An explicit quantization is given of certain skew-symmetric solutions of the
classical Yang-Baxter, yielding a family of $R$-matrices which generalize to
higher dimensions the Jordanian $R$-matrices. Three different approaches to
their construction are given: as twists of degenerations of the Shibukawa-Ueno
Yang-Baxter operators on meromorphic functions; as boundary solutions of the
quantum Yang-Baxter equation; via a vertex-IRF transformation from solutions to
the dynamical Yang-Baxter equation.

</DOC>
<DOC>
<DOCNO> 85095 </DOCNO>
Field Theory in Branching Spaces


  We consider a spacetime formed by several pieces having common timelike
boundary which plays the role of a junction between them. We establish junction
conditions for fields of various spin and derive the resulting laws of wave
propagation through the junction, which turn out to be quite similar for fields
of all spins. As an application, we consider the case of branching
four-dimensional spacetime that may arise in the context of the theory of
quantum creation of a closed universe on the background of a big mother
universe. The theory developed can also be applied to brane-world models and to
the superstring theory.

</DOC>
<DOC>
<DOCNO> 13154 </DOCNO>
Molecular Dynamics Results on the Pressure Tensor of Polymer Films


  Polymeric thin films of various thicknesses, confined between two repulsive
walls, have been studied by molecular dynamics simulations. Using the
anisotropy of the perpendicular and parallel components of the pressure tensor
the surface tension of the system is calculated for a wide range of temperature
and for various film thicknesses. Three methods of determining the pressure
tensor are compared: the method of Irving and Kirkwood (IK), an approximation
thereof (IK1), and the method of Harasima (H). The IK- and the H-methods differ
in the expression for the parallel component, but not for the normal component
of the pressure tensor. Both methods yield a constant normal component
throughout the film, as required by mechanical stability, whereas the
IK1-method leads to strong oscillations. However, all methods give the same
expression for the surface tension.

</DOC>
<DOC>
<DOCNO> 118616 </DOCNO>
ASCA Observation of the New Transient X-ray Pulsar XTE J0111.2-7317 in


  The new transient X-ray pulsar XTE J0111.2-7317 was observed with Advanced
Satellite for Cosmology and Astrophysics (ASCA) on 1998 November 18, a few days
after its discovery with the Proportional Counter Array onboard the Rossi X-ray
Timing Explorer. The source was detected at a flux level of 3.6x10^-10 erg
cm^-2 s^-1 in the 0.7--10.0 keV band, which corresponds to the X-ray luminosity
of 1.8x10^38 erg s^-1, if a distance of 65 kpc for this pulsar in the Small
Magellanic Cloud is assumed. Nearly sinusoidal pulsations with a period of
30.9497 +/- 0.0004 s were unambiguously detected during the ASCA observation.
The pulsed fraction is low and slightly energy dependent with average value of
\~27%. The energy spectrum shows a large soft excess below ~2 keV when fitted to
a simple power-law type model. The soft excess is eliminated if the spectrum is
fitted to an ``inversely broken power-law'' model, in which photon indices
below and above a break energy of 1.5 keV are 2.3 and 0.8, respectively. The
soft excess can also be described by a blackbody or a thermal bremsstrahlung
when the spectrum above ~2 keV is modeled by a power-law. In these models,
however, the thermal soft component requires a very large emission zone, and
hence it is difficult to explain the observed pulsations at energies below 2
keV. A bright state of the source enables us to identify a weak iron line
feature at 6.4 keV with an equivalent width of 50 +/- 14 eV. Pulse phase
resolved spectroscopy revealed a slight hardening of the spectrum and marginal
indication of an increase in the iron line strength during the pulse maximum.

</DOC>
<DOC>
<DOCNO> 151079 </DOCNO>
The Signature Triality of Majorana-Weyl Spacetimes


  Higher dimensional Majorana-Weyl spacetimes present space-time dualities
which are induced by the Spin(8) triality automorphisms. Different signature
versions of theories such as 10-dimensional SYM's, superstrings, five-branes,
F-theory, are shown to be interconnected via the S_3 permutation group.
Bilinear and trilinear invariants under space-time triality are introduced and
their possible relevance in building models possessing a space-versus-time
exchange symmetry is discussed. Moreover the Cartan's ``vector/chiral
spinor/antichiral spinor" triality of SO(8) and SO(4,4) is analyzed in detail
and explicit formulas are produced in a Majorana-Weyl basis. This paper is the
extended version of hep-th/9907148.

</DOC>
<DOC>
<DOCNO> 170555 </DOCNO>
Phase Locking of Remote Clocks Using Quantum Entanglement


  The proposal by Jozsa et al. to synchronize remote clocks is incomplete
because no prescription exists for creating the required prior non-degenerate
entanglement, given that the relative phase between the two clocks is unknown.
We show how a degenerate entanglement, created without this phase information,
can be used to determine the relative phase between the remote clocks, via the
interference between the co- and counter-rotating excitations of a two-level
atom. As such, the protocol offered here achieves the goal of phase-locking
remote clocks without transmitting any timing signal.

</DOC>
<DOC>
<DOCNO> 71618 </DOCNO>
The Cosmological Bulk Neutrino Catastrophe


  Recent phenomenological models which posit extra spacelike dimensions in
which (bulk) neutrinos are allowed to propagate are shown to have significant
cosmological effects whenever the size of the largest extra dimension is R > 1
fm (1/R < 200 MeV). Specifically, limits from the cosmic microwave background
(CMB) anisotropies as measured by BOOMERanG, big bang nucleosynthesis,
deuterium and Li-6 photoproduction, diffuse photon backgrounds, and structure
formation/age considerations are shown to translate into broad constraints on
bulk neutrino schemes. These present challenges for many recent light neutrino
mass models invoking large volume toroidal compactifications as well as those
involving densely spaced Kaluza-Klein (KK) modes. We discuss how these models
would have to be modified to escape constraint and under what finely-tuned
circumstances bulk neutrino KK tower states could constitute a new kind of dark
matter. Future CMB observations (e.g., MAP, Planck) may extend these
constraints or discover signatures of bulk neutrino models with R ~ 0.1 fm.

</DOC>
<DOC>
<DOCNO> 84871 </DOCNO>
Rotating Relativistic Thin Disks


  Two families of models of rotating relativistic disks based on Taub-NUT and
Kerr metrics are constructed using the well-known "displace, cut and reflect"
method. We find that for disks built from a generic stationary axially
symmetric metric the "sound velocity", $(pressure/density)^{1/2}$, is equal to
the geometric mean of the prograde and retrograde geodesic circular velocities
of test particles moving on the disk. We also found that for generic disks we
can have zones with heat flow. For the two families of models studied the
boundaries that separate the zones with and without heat flow are not stable
against radial perturbations (ring formation).

</DOC>
<DOC>
<DOCNO> 69017 </DOCNO>
Weak and Magnetic Inelastic Scattering of Antineutrinos on Atomic


  Neutrino scattering on electrons is considered as a tool for laboratory
searches of the neutrino magnetic moment. We study inelastic
$\bar\nu_ee^-$-scattering on electrons bound in the germanium (Z=32) and iodine
(Z=53) atoms for antineutrinos generated in a nuclear reactor core and also in
the $^{90}$Sr-$^{90}$Y and $^{147}$Pm artificial sources. Using the
relativistic Hartree-Fock-Dirac model, we calculate both the magnetic and weak
scattering cross sections for the recoil electron energy range of 1 to 100 keV
where a higher sensitivity to the neutrino magnetic moment could be achieved.
Particular attention is paid to the approximate procedure which allows us to
take into account the effects of atomic binding on the inelastic scattering
spectra in a simple way.

</DOC>
<DOC>
<DOCNO> 152038 </DOCNO>
Exact Noncommutative Solitons


  We find exact solitons in a large class of noncommutative gauge theories
using a simple solution generating technique. The solitons in the effective
field theory description of open string field theory are interpreted as
D-branes for any value of the noncommutativity. We discuss the vacuum structure
of open string field theory in view of our results.

</DOC>
<DOC>
<DOCNO> 119785 </DOCNO>
Light Element Abundance Patterns in the Orion Association: I) HST


  The boron abundances for two young solar-type members of the Orion
association, BD -6 1250 and HD 294297, are derived from HST STIS spectra of the
B I transition at 2496.771 A. The best-fit boron abundances for the target
stars are 0.13 and 0.44 dex lower than the solar meteoritic value of log
e(B)=2.78. An anticorrelation of boron and oxygen is found for Orion when these
results are added to previous abundances obtained for 4 B-type stars and the
G-type star BD -5 1317. An analysis of the uncertainties in the abundance
calculations indicates that the observed anticorrelation is probably real. The
B versus O relation observed in the Orion association does not follow the
positive correlation of boron versus oxygen which is observed for the field
stars with roughly solar metallicity. The observed anticorrelation can be
accounted for by a simple model in which two poorly mixed components of gas
(supernova ejecta and boron-enriched ambient medium) contribute to the new
stars that form within the lifetime of the association. This model predicts an
anticorrelation for Be as well, at least as strong as for boron.

</DOC>
<DOC>
<DOCNO> 119435 </DOCNO>
X-ray Emission of Mkn 421: New Clues From Its Spectral Evolution. II.


  Mkn 421 was repeatedly observed with BeppoSAX in 1997-1998. The source showed
a very rich phenomenology, with remarkable spectral variability. This is the
second of two papers presenting the results of a thorough temporal and spectral
analysis of all the data available to us, focusing in particular on the flare
of April 1998, which was simultaneously observed also at TeV energies. The
spectral analysis and correlations are presented in this paper, while the data
reduction and timing analysis are the content of the companion paper. The
spectral evolution during the flare has been followed over few ks intervals,
allowing us to detect for the first time the peak of the synchrotron component
shifting to higher energies during the rising phase, and then receding. This
spectral analysis nicely confirms the delay of the flare at the higher
energies, which in Paper I we quantified as a hard lag of a few ks.
Furthermore, at the highest energies, evidence is found of variations of the
inverse Compton component. The spectral and temporal information obtained
challenge the simplest models currently adopted for the (synchrotron) emission
and most importantly provide clues on the particle acceleration process. A
scenario accounting for all the observational constraints is discussed, where
electrons are injected at progressively higher energies during the development
of the flare, and the achromatic decay is ascribed to the source light crossing
time exceeding the particle cooling timescales.

</DOC>
<DOC>
<DOCNO> 150658 </DOCNO>
A Geometrical Description of the Consistent and Covariant Chiral Anomaly


  A geometrical interpretation of the consistent and covariant chiral anomaly
is done in the space-time respective Hamiltonian framework.

</DOC>
<DOC>
<DOCNO> 151100 </DOCNO>
Difficulties in a Kind of Averaging Procedure for Constructing


  We prove that a kind of averaging procedure for constructing gauge-invariant
operators(or functionals) out of gauge-variant ones is erroneous and
inapplicable for a large class of operators(or functionals).

</DOC>
<DOC>
<DOCNO> 121405 </DOCNO>
The Discovery of a State Dependent Hard Tail in the X-ray Spectrum of


  We report results of a BeppoSAX (0.1-200 keV) observation of the Z-type low
mass X-ray binary GX 17+2. The source was on the so-called Horizontal and
Normal branches. Energy spectra were selected based on the source position in
the X-ray hardness-intensity diagram. The continuum could be fairly well
described by the sum of a ~0.6 keV blackbody, contributing ~10% of the observed
0.1-200 keV flux, and a Comptonized component, resulting from upscattering of
\~1 keV seed photons by an electron cloud with temperature of ~3 keV and optical
depth of ~10. Iron K-line and edge were also present at energies 6.7 and 8.5
keV, respectively. In the spectra of the Horizontal branch a hard tail was
clearly detected at energies above ~30 keV. It could be fit by a power law of
photon index ~2.7, contributing ~8% of the source flux. This component
gradually faded as the source moved towards the Normal branch, where it was no
longer detectable. We discuss the possible origin of this component and the
similarities with the spectra of Atoll sources and black hole X-ray binaries.

</DOC>
<DOC>
<DOCNO> 150764 </DOCNO>
Anyon spin and the exotic central extension of the planar Galilei group


  We show that the second central extension of the Galilei group in (2+1)
dimensions corresponds to spin, which can be any real number.

</DOC>
<DOC>
<DOCNO> 9146 </DOCNO>
An asymptotic solution for the SHE equations describing the charge


  In this paper an asymptotic solution of the spherical harmonics equations
describing the charge transport in semiconductors is found. This solution is
compared with a numerical solution for bulk silicon device. We also indicate
application of this solution to the construction of high field hydrodynamical
models.

</DOC>
<DOC>
<DOCNO> 100453 </DOCNO>
The electromagnetic self-force on a charged spherical body slowly


  The self-force of classical electrodynamics on a charged "rigid" body of
radius R is evaluated analytically for the body undergoing a slow (i.e., with a
speed v<<c), slight (i.e., small compared to R), and temporary displacement
from an initial position of rest. The results are relevant to the
Bohr-Rosenfeld analysis of the measurability of the electromagnetic field,
which has been the subject of a recent controversy.

</DOC>
<DOC>
<DOCNO> 13649 </DOCNO>
Theory for Phase Transitions in Insulating Vanadium Oxide


  We show that the recently proposed S=2 bond model with orbital degrees of
freedom for insulating V$_{2}$O$_{3}$ not only explains the anomalous magnetic
ordering, but also other mysteries of the magnetic phase transition. The model
contains an additional orbital degree of freedom that exhibits a zero
temperature quantum phase transtion in the Ising universality class.

</DOC>
<DOC>
<DOCNO> 11507 </DOCNO>
Stiction, Adhesion Energy and the Casimir Effect in Micromechanical


  We measure the adhesion energy of gold using a micromachined doubly-clamped
beam. The stress and stiffness of the beam are characterized by measuring the
spectrum of mechanical vibrations and the deflection due to an external force.
To determine the adhesion energy we induce stiction between the beam and a
nearby surface by capillary forces. Subsequent analysis yields a value $\gamma
=0.06$ J/m$^{2}$ that is a factor of approximately six smaller than predicted
by idealized theory. This discrepancy may be resolved with revised models that
include surface roughness and the effect of adsorbed monolayers intervening
between the contacting surfaces in these mesoscopic structures.

</DOC>
<DOC>
<DOCNO> 152472 </DOCNO>
Hidden Virasoro Symmetry of the Sine Gordon Theory


  In the framework of the Sine-Gordon (SG) theory we will present the
construction of a dynamical Virasoro symmetry which has nothing to do with the
space-time Virasoro symmetry of 2D CFT. Although, it is non-local in the SG
field theory, nevertheless it gives rise to a local action on specific
N-soliton solution variables. These {\it analytic} variables possess a
beautiful geometrical meaning and enter the Form Factor expressions. At the
end, we will also give some preliminary hints about the quantisation.

</DOC>
<DOC>
<DOCNO> 84687 </DOCNO>
The Long-Time Dynamics of Dirac Particles in the Kerr-Newman Black Hole


  We consider the Cauchy problem for the massive Dirac equation in the
non-extreme Kerr-Newman geometry outside the event horizon. We derive an
integral representation for the Dirac propagator involving the solutions of the
ODEs which arise in Chandrasekhar's separation of variables. It is proved that
for initial data in L^\infty_loc near the event horizon with L^2 decay at
infinity, the probability of the Dirac particle to be in any compact region of
space tends to zero as t goes to infinity. This means that the Dirac particle
must either disappear in the black hole or escape to infinity.

</DOC>
<DOC>
<DOCNO> 100039 </DOCNO>
Proof of the Rokhlin's Conjecture on Arnold's surfaces


  In this paper we prove that Arnold Surfaces of all real algebraic curves of
even degree with non-empty real part are standard (Rokhlin's Conjecture). There
is an obvious connection with classification of Arnold Surfaces up to isotopy
of S^4 and Hilbert's Sixteen Problem on the arrangements of connected real
components of curves. First, we consider some M-curves, i.e curves of a
prescribed degree having the greatest possible number of connected real
components, and prove that Arnold surfaces of these curves are standard.
Afterwards, we exhibit a procedure of modification "perestroika" of these
M-curves which allows to prove the Rokhlin's Conjecture.

</DOC>
<DOC>
<DOCNO> 118659 </DOCNO>
Biases in Expansion Distances of Novae Arising from the Prolate Geometry


  (abridged) Expansion distances (or expansion parallaxes) for classical novae
are based on comparing a measurement of the shell expansion velocity,
multiplied by the time since outburst, with some measure of the angular size of
the shell. We review and formalize this method in the case of prolate
spheroidal shells. We present expressions for the maximum line-of-sight
velocity from a complete, expanding shell and for its projected major and minor
axes, in terms of the intrinsic axis ratio and the inclination of the polar
axis to the line of sight. For six distinct definitions of ``angular size'', we
tabulate the error in distance that is introduced under the assumption of
spherical symmetry (i.e., without correcting for inclination and axis ratio).
The errors can be significant and systematic, affecting studies of novae
whether considered individually or statistically. Each of the six estimators
overpredicts the distance when the polar axis is close to the line of sight,
and most underpredict the distance when the polar axis is close to the plane of
the sky. The straight mean of the projected semimajor and semiminor axes gives
the least distance bias for an ensemble of randomly oriented prolate shells.
The best individual expansion distances, however, result from a full
spatio-kinematic modeling of the nova shell. We discuss several practical
complications that affect expansion distance measurements of real nova shells.
Nova shell expansion distances be based on velocity and angular size
measurements made contemporaneously if possible, and the same ions and
transitions should be used for the imaging and velocity measurements. We
emphasize the need for complete and explicit reporting of measurement
procedures and results, regardless of the specific method used.

</DOC>
<DOC>
<DOCNO> 70884 </DOCNO>
Neutrino Mass^2 Inferred from the Cosmic Ray Spectrum and Tritium Beta


  An earlier prediction of a cosmic ray neutron line right at the energy of the
knee of the cosmic ray spectrum was based on the speculation that the electron
neutrino is a tachyon whose mass is reciprocally related to the energy of the
knee, $E_k$. Given the large uncertainty in $E_k$, the values of ${m_\nu}^2$
corresponding to it are consistent with values recently reported in tritium
beta decay experiments.

</DOC>
<DOC>
<DOCNO> 118389 </DOCNO>
Repulsive Dark Matter


  It seems necessary to suppress, at least partially, the formation of
structure on subgalactic scales. As an alternative to warm or collisional dark
matter, I postulate a condensate of massive bosons interacting via a repulsive
interparticle potential, plus gravity. This leads to a minimum lengthscale for
bound objects, and to superfluidity. Galactic dynamics may differ significantly
from that of more generic dark matter in not unwelcome ways, especially in the
core. Such particles can be realized as quanta of a relativistic massive scalar
field with a quartic self-interaction. At high densities, the equation of state
has the same form as that of an ideal relativistic gas despite the
interactions. If the nonrelativistic lengthscale is of order a kiloparsec, then
the energy density in these particles was comparable to that of photons at
early times, but small enough to avoid conflict with primordial
nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 8039 </DOCNO>
Black-Scholes option pricing within Ito and Stratonovich conventions


  Options financial instruments designed to protect investors from the stock
market randomness. In 1973, Fisher Black, Myron Scholes and Robert Merton
proposed a very popular option pricing method using stochastic differential
equations within the Ito interpretation. Herein, we derive the Black-Scholes
equation for the option price using the Stratonovich calculus along with a
comprehensive review, aimed to physicists, of the classical option pricing
method based on the Ito calculus. We show, as can be expected, that the
Black-Scholes equation is independent of the interpretation chosen. We
nonetheless point out the many subtleties underlying Black-Scholes option
pricing method.

</DOC>
<DOC>
<DOCNO> 13852 </DOCNO>
Low Energy Properties of Ferrimagnetic 2-leg Ladders: a Lanczos study


  We apply the Lanczos method to a 2-leg ladder with mixed spins of magnitudes
$(S_1,S_2)=(1,1/2)$ located at alternating positions along the ladder. The
effect of dimerization $\gamma$ is also considered according to two different
patterns. A Spin Wave Theory (SWT) is applied to this model predicting one
gapless branch with ferromagnetic properties and another gapful branch with
antiferromagnetic nature as low energy excitations of the model. We compute the
ground state energies, Ferro- and AF-excitation gaps, magnetizations and
correlation functions as a function of $J'$ and $\gamma$ which results into a
fine estimate of the phase diagram. The Lanczos results are compared with the
SWT analysis and a qualitative agreement is found but with numerical
discrepancies. We also study numerically the Spin-Peierls instability and find
that it is conditional for any value of $ J' \in (0, 2)$ and both dimerization
patterns.

</DOC>
<DOC>
<DOCNO> 119778 </DOCNO>
The discovery of quiescent X-ray emission from SAX J1808.4-3658, the


  We report on a 20 ks BeppoSAX observation of the transient 2.5 ms X-ray
pulsar SAX J1808.4-3658 in its quiescent state. A source at a level of ~ 3 x
10^-3 c/s was detected with the BeppoSAX/MECS at a position consistent with
that of SAX J1808.4-3658. The inferred 0.5-10 keV luminosity was to that
measured from other quiescent low mass X-ray transients hosting an old neutron
star. This result is discussed in the light of the propeller and radio pulsar
shock emission models for the quiescent emission of these systems.

</DOC>
<DOC>
<DOCNO> 102200 </DOCNO>
Strict Quantization of Solvable Symmetric Spaces


  This work is a contribution to the area of Strict Quantization (in the sense
of Rieffel) in the presence of curvature and non-Abelian group actions. More
precisely, we use geometry to obtain explicit oscillatory integral formulae for
strongly invariant strict deformation quantizations of a class of solvable
symplectic symmetric spaces. Each of these quantizations gives rise to a field
of (pre)-C*-algebras whose fibers are function algebras which are closed under
the deformed product. The symmetry group of the symmetric space acts on each
fiber by C*-algebra automorphisms.

</DOC>
<DOC>
<DOCNO> 12454 </DOCNO>
Random quantum magnets with broad disorder distribution


  We study the critical behavior of Ising quantum magnets with broadly
distributed random couplings (J), such that $P(\ln J) \sim |\ln
J|^{-1-\alpha}$, $\alpha>1$, for large $|\ln J|$ (L\'evy flight statistics).
For sufficiently broad distributions, $\alpha<\alpha_c$, the critical behavior
is controlled by a line of fixed points, where the critical exponents vary with
the L\'evy index, $\alpha$. In one dimension, with $\alpha_c=2$, we obtaind
several exact results through a mapping to surviving Riemann walks. In two
dimensions the varying critical exponents have been calculated by a numerical
implementation of the Ma-Dasgupta-Hu renormalization group method leading to
$\alpha_c \approx 4.5$. Thus in the region $2<\alpha<\alpha_c$, where the
central limit theorem holds for $|\ln J|$ the broadness of the distribution is
relevant for the 2d quantum Ising model.

</DOC>
<DOC>
<DOCNO> 101805 </DOCNO>
Rationality of conformally invariant local correlation functions on


  Rationality of the Wightman functions is proven to follow from energy
positivity, locality and a natural condition of global conformal invariance
(GCI) in any number D of space-time dimensions. The GCI condition allows to
treat correlation functions as generalized sections of a vector bundle over the
compactification of Minkowski space and yields a strong form of locality valid
for all non-isotropic intervals if assumed true for space-like separations.

</DOC>
<DOC>
<DOCNO> 102886 </DOCNO>
Combinatorial R matrices for a family of crystals : B^{(1)}_n,


  For coherent families of crystals of affine Lie algebras of type B^{(1)}_n,
D^{(1)}_n, A^{(2)}_{2n} and D^{(2)}_{n+1} we describe the combinatorial R
matrix using column insertion algorithms for B,C,D Young tableaux. 

</DOC>
<DOC>
<DOCNO> 39686 </DOCNO>
Evidence for a dynamic origin of charge


  The fundamental equations of particle motion lead to a modified Poisson
equation including dynamic charge. This charge derives from density
oscillations of a particle; it is not discrete, but continuous. Within the
dynamic model of hydrogen it accounts for all features of electron proton
interactions, its origin are density oscillations of the proton. We propose a
new system of electromagnetic units, based on meter, kilogram, and second,
bearing on these findings. The system has none of the disadvantages of
traditional three-unit systems. On the basis of our theoretical model we can
genuinely derive the scaling factor between electromagnetic and mechanic
variables, which is equal, within a few percent, to Planck's constant h. The
implications of the results in view of unifying gravity and quantum theory are
discussed. It seems that the hypothetical solar gravity waves, in the low
frequency range of the electromagnetic spectrum, are open to experimental
detection.

</DOC>
<DOC>
<DOCNO> 10125 </DOCNO>
Correlated percolation patterns in PEF damaged cellular material


  We present results of numerical and experimental investigation of the
electric breakage of a cellular material in pulsed electric fields (PEF). The
numerical model simulates the conductive properties of a cellular material by a
two-dimensional array of biological cells. The application of an external field
in the form of the idealised square pulse sequence with a pulse duration
$t_{i}$, and a pulse repetition time $\Delta t$ is assumed. The simulation
model includes the known mechanisms of temporal and spatial evolution of the
conductive properties of different microstructural elements in a tissue. The
kinetics of breakage at different values of electric field strength $E$,
$t_{i}$ and $\Delta t$ was studied in experimental investigation. We propose
the hypothesis for the nature of tissue properties evolution after PEF
treatment and consider this phenomena as a correlated percolation, which is
governed by two key processes: resealing of cells and moisture transfer
processes inside the cellular structure. The breakage kinetics was shown to be
very sensitive to the repetition times $\Delta t$ of the PEF treatment. We
observed correlated percolation patterns in a case when $\Delta t$ exceeds the
characteristic time of the processes of moisture transfer and random
percolation patterns in other cases. The long-term mode of the pulse repetition
times in PEF treatment allows us to visualize experimentally the macroscopic
percolation channels in the sample.

</DOC>
<DOC>
<DOCNO> 40221 </DOCNO>
Muon Track Matching


  For most physical processes the tracks observed in the muon stations must be
matched with the corresponding tracks in the inner tracker, the external muon
system providing muon identification and triggering but the tracker points
giving the precise momentum measurement at lower momenta. For high momenta the
momentum resolution is much improved by the interconnection of inner and outer
measurements. The matching of outer and inner measurements is more delicate in
case of muons embedded in jets. A study of the matching procedure was carried
out using samples of (b, anti b) jets at high Pt, requiring (b, anti b) -> mu
decays.

</DOC>
<DOC>
<DOCNO> 174590 </DOCNO>
$\phi$ and $\omega$ Meson Production in pp Reactions at $p_{lab}$=3.67


  The exclusive production cross sections for $\omega$ and $\phi$ mesons have
been measured in proton-proton reactions at $p_{lab}=3.67$ GeV/c. The observed
$\phi/\omega$ cross section ratio is $(3.8\pm0.2^{+1.2}_{-0.9})\times 10^{-3}$.
After phase space corrections, this ratio is enhanced by about an order of
magnitude relative to naive predictions based upon the Okubo-Zweig-Iizuka (OZI)
rule, in comparison to an enhancement by a factor $\sim 3$ previously observed
at higher beam momenta. The modest increase of this enhancement near the
production threshold is compared to the much larger increase of the
$\phi/\omega$ ratio observed in specific channels of $\bar pp$ annihilation
experiments. Furthermore, differential cross section results are also presented
which indicate that although the $\phi$ meson is predominantly produced from a
$^3P_1$ proton-proton entrance channel, other partial waves contribute
significantly to the production mechanism at this beam momentum.

</DOC>
<DOC>
<DOCNO> 117928 </DOCNO>
A Review of Mass Estimates for Galactic Dark Matter Objects


  Empirical mass estimates for galactic dark matter objects, published between
December 1991 and May 1999, are presented in tabular and graphical forms.
Trends in the data are identified and uncertainties are discussed. Similarities
among various stellar and dark matter mass functions are noted, and a possible
identification of the galactic dark matter objects is suggested.

</DOC>
<DOC>
<DOCNO> 169976 </DOCNO>
Quantum Communication Complexity


  This paper surveys the field of quantum communication complexity. Some
interesting recent results are collected concerning relations to classical
communication, lower bound methods, one-way communication, and applications of
quantum communication complexity.

</DOC>
<DOC>
<DOCNO> 11811 </DOCNO>
Photoemission Spectroscopy from Inhomogeneous Models of Cuprates


  We investigate the electronic dynamics in the underdoped cuprates focusing on
the effects of one-dimensional charge stripes. We address recent experimental
Angular-Resolved Photoemission Spectra results on
(La$_{1.28}$Nd$_{0.6}$Sr$_{0.12}$)CuO$_4$. We find that various inhomogeneous
models can account for the distribution of quasiparticle weights close to
momentum ${\bf k}=(\pi,0)$ and symmetry related points. The observed flat
dispersion region around the same ${\bf k}$ point can only be addressed by
certain classes of those inhomogeneous models which locally break spin
symmetry. Homogeneous models including hopping elements up to second neighbors
cannot reproduce the experimental quasiparticle weight, since most of it is
centered around ${\bf k}=(\frac {\pi}{2},\frac {\pi} {2})$.

</DOC>
<DOC>
<DOCNO> 67802 </DOCNO>
Longitudinal Spin Dependence of Massive Lepton Pair Production


  We show that massive lepton-pair production, the Drell-Yan process, should be
a good source of independent constraints on the polarized gluon density, free
from the experimental and theoretical complications of photon isolation that
beset studies of prompt photon production. We provide predictions for the
spin-averaged and spin-dependent differential cross sections as a function of
transverse momentum $Q_T$ at energies relevant for the Relativistic Heavy Ion
Collider (RHIC) at Brookhaven.

</DOC>
<DOC>
<DOCNO> 102730 </DOCNO>
Sh-Lie algebras Induced by Gauge Transformations


  The physics of ``particles of spin $\leq 2$'' leads to representations of a
Lie algebra $\Xi$ of gauge parameters on a vector space $\Phi$ of fields.
Attempts to develop an analogous theory for spin $>2$ have failed; in fact,
there are claims that such a theory is impossible (though we have been unable
to determine the hypotheses for such a `no-go' theorem). This led BBvD
[burgers:diss,BBvd:three,BBvD:probs] to generalize to `field dependent
parameters' in a setting where some analysis in terms of smooth functions is
possible. Having recognized the resulting structure as that of an sh-lie
algebra ($L_\infty$-algebra), we have now reproduced their structure entirely
algebraically, hopefully shedding some light on what is going on.

</DOC>
<DOC>
<DOCNO> 179033 </DOCNO>
Deuteron P-Wave in Elastic Backward Proton-Deuteron Scattering


  The elastic backward proton-deuteron scattering is analyzed within a fully
covariant approach based on the invariant expansion of the reaction amplitude.
The method of calculation of any observables for any reaction mechanism is
developed. The cross section and spin observables, like tensor analyzing power
and polarization transfer coefficient etc., are investigated in explicit form
within framework of the impulse approximation using different kinds of the
relativistic deuteron wave function (DWF) with P-wave components. Our results
of numerical calculation for complete set of polarization observables are
compared with the experimental data and other calculations performed within
both the non-relativistic and relativistic approaches. An experimental
verification of the reaction mechanism is suggested by constructing some
combinations of different observables.

</DOC>
<DOC>
<DOCNO> 68940 </DOCNO>
In-Plane Elliptic Flow of Resonance Particles in Relativistic Heavy-Ion


  We analyze the second Fourier coefficient $v_2$ of the pion azimuthal
distribution in non-central heavy-ion collisions in a relativistic hydrodynamic
model. The exact treatment of the decay kinematics of resonances leads to
almost vanishing azimuthal anisotropy of pions near the midrapidity, while the
matter elliptic flow is in-plane at freeze-out. In addition, we reproduce the
rapidity dependence of $v_2$ for pions measured in non-central Pb + Pb
collisions at 158$A$ GeV. This suggests that resonance particles as well as
stable particles constitute the in-plane flow and are important ingredients for
the understanding of the observed pion flow.

</DOC>
<DOC>
<DOCNO> 118997 </DOCNO>
HST/NICMOS Observations of IZw18 - revealing a population of old AGB


  I present the first results from a HST/NICMOS imaging study of the most
metal-poor blue compact dwarf galaxy IZw18. The near infrared color-magnitude
diagram (CMD) is dominated by two populations, one 10-20 Myr population of red
super giants and one 0.5-5 Gyr population of asymptotic giant branch stars.
Stars older than 1 Gyr are required to explain the observed CMD at the adopted
distance of 12.6 Mpc, showing that IZw18 is not a young galaxy. The results
hold also if the distance to IZw18 i s significantly larger. This rules out the
possibility that IZw18 is a truly young galaxy formed recently in the local
universe.

</DOC>
<DOC>
<DOCNO> 178570 </DOCNO>
A Phenomenological Expression for Deuteron Electromagnetic Form Factors


  Removed by arXiv admin.

</DOC>
<DOC>
<DOCNO> 99686 </DOCNO>
Chern character for the Schwartz algebra of p-adic GL(n)


  We construct a Chern character map from the K-theory of the reduced C^*
algebra of the p-adic GL(n) with values in the periodic cyclic homology of the
Schwartz algebra of this group. We prove that this map is an isomorphism after
tensoring with C by comparing an explicit formula, stated in the algebraic case
by Cuntz and Quillen, with the classical Chern character. This Chern character
is a crucial ingredient in the proof of the Baum-Connes conjecture for the
p-adic GL(n) due to Baum, Higson and Plymen.

</DOC>
<DOC>
<DOCNO> 116323 </DOCNO>
Relationships between a roller and a dynamic pressure distribution in


  We investigated numerically the relation between a roller and the pressure
distribution to clarify the dynamics of the roller in circular hydraulic jumps.
We found that a roller which characterizes a type II jump is associated with
two high pressure regions after the jump, while a type I jump (without the
roller) is associated with only one high pressure region. Our numerical results
show that building up an appropriate pressure field is essential for a roller.

</DOC>
<DOC>
<DOCNO> 150717 </DOCNO>
Field Theory as a Matrix Model


  A new formulation of four dimensional quantum field theories, such as scalar
field theory, is proposed as a large N limit of a special NxN matrix model. Our
reduction scheme works beyond planar approximation and applies for QFT with
finite number of fields. It uses quenched coordinates instead of quenched
momenta of the old Eguchi-Kawai reduction known to yield correctly only the
planar sector of quantum field theory. Fermions can be also included.

</DOC>
<DOC>
<DOCNO> 123216 </DOCNO>
Possible evidence for a variable fine structure constant from QSO


  Comparison of quasar absorption spectra with laboratory spectra allow us to
probe possible variations in the fundamental constants over cosmological
time-scales. In a companion paper we present an analysis of Keck/HIRES spectra
and report possible evidence suggesting that the fine structure constant,
alpha, may have been smaller in the past: da/a = (-0.72 +/- 0.18) * 10^{-5}
over the redshift range 0.5 < z < 3.5. In this paper we describe a
comprehensive investigation into possible systematic effects. Most of these do
not significantly influence our results. When we correct for those which do
produce a significant systematic effect in the data, the deviation of da/a from
zero becomes more significant. We are lead increasingly to the interpretation
that alpha was slightly smaller in the past.

</DOC>
<DOC>
<DOCNO> 150629 </DOCNO>
Study of a Model of Quantum Electrodynamics


  This paper studies the model of the quantum electrodynamics (QED) of a single
nonrelativistic electron due to W. Pauli and M. Fierz and studied further by P.
Blanchard. This model exhibits infrared divergence in a very simple context.
The infrared divergence is associated with the inequivalence of the Hilbert
spaces associated with the free Hamiltonian and with the complete Hamiltonian.
Infrared divergences that are visible in the perturbative description disappear
in the space of the clothed electrons. In this model when the Hamiltonian is
expressed in terms of the ``physical'' fields that create the electron together
with its cloud of soft photons the variational principle suggested earlier can
be applied. At finite time the Heisenberg field of the model acts in the space
of the perturbative electron together with a finite number of perturbative
photons, while the ``physical'' field can be chosen to act in the space of the
exact (``physical'') electron eigenstates together with a finite number of
physical photons. The space of the physical (or clothed) electron states can be
chosen to be a Fock space.

</DOC>
<DOC>
<DOCNO> 102488 </DOCNO>
A module frame concept for Hilbert C*-modules


  The goal of the present paper is a short introduction to a general module
frame theory in C*-algebras and Hilbert C*-modules. The reported investigations
rely on the idea of geometric dilation to standard Hilbert C*-modules over
unital C*-algebras that possess orthonormal bases, and of reconstruction of the
frames by projections and other bounded module operators with suitable ranges.
We obtain frame representation and decomposition theorems, as well as
similarity and equivalence results. The relative position of two and more
frames in terms of being complementary or disjoint is investigated in detail.
In the last section some recent results by P. G. Casazza are generalized to our
setting. The Hilbert space situation appears as a special case. For detailled
proofs we refer to another paper also contained in the ArXiv.

</DOC>
<DOC>
<DOCNO> 120802 </DOCNO>
Cosmic Strings Lens Phenomenology Revisited


  We present investigations of lens phenomenological properties of cosmic
strings for deep galaxy surveys. General results that have obtained for lineic
energy distribution are presented first. We stress that generically the local
convergence always vanishes in presence of strings although there might be some
significant distortions. We then propose a simplified model of strings, we call
``Poisson strings'', for which exhaustive investigations can be done either
numerically or analytically.

</DOC>
<DOC>
<DOCNO> 152257 </DOCNO>
Short harmonic superfields and light-cone gauge in super-Yang-Mills


  We analyze the superfield equations of the 4-dimensional N=2 and N=4
SYM-theories using light-cone gauge conditions and the harmonic-superspace
approach. The harmonic superfield equations of motion are drastically
simplified in this gauge, in particular, the basic harmonic-superfield matrices
and the corresponding harmonic analytic gauge connections become nilpotent
on-shell.

</DOC>
<DOC>
<DOCNO> 80844 </DOCNO>
Dirac eigenvalues and eigenvectors at finite temperature


  We investigate the eigenvalues and eigenvectors of the staggered Dirac
operator in the vicinity of the chiral phase transition of quenched SU(3)
lattice gauge theory. We consider both the global features of the spectrum and
the local correlations. In the chirally symmetric phase, the local correlations
in the bulk of the spectrum are still described by random matrix theory, and we
investigate the dependence of the bulk Thouless energy on the simulation
parameters. At and above the critical point, the properties of the low-lying
Dirac eigenvalues depend on the $Z_3$-phase of the Polyakov loop. In the real
phase, they are no longer described by chiral random matrix theory. We also
investigate the localization properties of the Dirac eigenvectors in the
different $Z_3$-phases.

</DOC>
<DOC>
<DOCNO> 40333 </DOCNO>
Direct measurement of Ab at the Z0 pole using a lepton tag


  We present a direct measurement of the parity violation parameter Ab, derived
from the left-right forward-backward asymmetry of b quarks tagged via leptons
from semileptonic decays. The lepton identification algorithm combines
information from tracking, calorimetry and from the SLD Cherenkov Ring Imaging
Detector. The value of Ab is extracted using a maximum likelihood fit to the
differential cross section for fermion production. Vertexing information and
decay kinematics have been used to discriminate among the different sources of
tagged leptons. A new treatment of mixing effects and of background
contamination has been introduced and a new vertexing algorithm has been used
in the muon analysis. Based on the 1993-1998 SLD sample of 550K hadronic Z0
decays with highly polarized electron beams, we have measured Ab with a ~3%
statistical error.

</DOC>
<DOC>
<DOCNO> 11667 </DOCNO>
A Cellular Automata Model for Citrus Variagated Chlorosis


  A cellular automata model is proposed to analyze the progress of Citrus
Variegated Chlorosis epidemics in S\~ao Paulo oranges plantation. In this model
epidemiological and environmental features, such as motility of sharpshooter
vectors which perform L\'evy flights, hydric and nutritional level of plant
stress and seasonal climatic effects, are included. The observed epidemics data
were quantitatively reproduced by the proposed model varying the parameters
controlling vectors motility, plant stress and initial population of diseased
plants.

</DOC>
<DOC>
<DOCNO> 84719 </DOCNO>
Non-time-orthogonal Reference Frames in the Theory of Relativity


  A simple, though rarely considered, thought experiment on relativistic
rotation is described in which internal inconsistencies in the theory of
relativity seem to arise. These apparent inconsistencies are resolved by
appropriate insight into the nature, and unique properties, of the
non-time-orthogonal rotating frame. The analysis also explains a heretofore
inexplicable experimental result.

</DOC>
<DOC>
<DOCNO> 69594 </DOCNO>
Reheating and dangerous relics in pre-big bang string cosmology


  We discuss the mechanism of reheating in pre-big bang string cosmology and we
calculate the amount of moduli and gravitinos produced gravitationally and in
scattering processes of the thermal bath. We find that this abundance always
exceeds the limits imposed by big-bang nucleosynthesis, and significant entropy
production is required. The exact amount of entropy needed depends on the
details of the high curvature phase between the dilaton-driven inflationary era
and the radiation era. We show that the domination and decay of the zero-mode
of a modulus field, which could well be the dilaton, or of axions, suffices to
dilute moduli and gravitinos. In this context, baryogenesis can be accomodated
in a simple way via the Affleck-Dine mechanism and in some cases the
Affleck-Dine condensate could provide both the source of entropy and the baryon
asymmetry.

</DOC>
<DOC>
<DOCNO> 120529 </DOCNO>
PSCz Superclusters: Detection, Shapes & Cosmological Implications


  We study the possibility of correctly identifying superclusters, from the
smooth galaxy density field of the PSCz redshift catalogue, and of recovering
their true shapes in the presence of a bias introduced by the coupling between
the selection function and the constant radius smoothing. Using simulations we
quantify such systematic biases in the smoothed PSCz density field and after
applying the necessary corrections we study the PSCz supercluster multiplicity
and morphologies using a differential geometry definition of shape. Our results
strongly suggest that filamentariness is the dominant morphological feature of
PSCz superclusters. Finally, we compare our results with those expected in
three different cosmological models and find that the LCDM model performs
better than Omega_m=1 CDM models.

</DOC>
<DOC>
<DOCNO> 121875 </DOCNO>
Gamma-ray line emission from OB associations and young open clusters: I.


  We have developed a new diagnostic tool for the study of gamma-ray emission
lines from radioactive isotopes (such as 26Al and 60Fe in conjunction with
other multi-wavelength observables of Galactic clusters, associations, and
alike objects. Our evolutionary synthesis models are based on the code of
Cervino & Mas-Hesse (1994), which has been updated to include recent stellar
evolution tracks, new stellar atmospheres for OB and WR stars, and
nucleosynthetic yields from massive stars during hydrostatic burning phases and
explosive SN II and SN Ib events. The temporal evolution of 26Al and 60Fe
production, the equivalent yield of 26Al per ionising O7 V star (yal), and
other observables are predicted for a coeval population. We also employed our
model to estimate the steady state nucleosynthesis of a population of solar
metallicity. To allow for a fully quantitative analysis of existing and future
multi-wavelength observations, we propose a Bayesian approach that allows the
inclusion of IMF richness effects and observational uncertainties in the
analysis. In particular, a Monte Carlo technique is adopted to estimate
probability distributions for all observables of interest. We outline the
procedure of exploiting these distributions by applying our model to a fictive
massive star association. Applications to existing observations of the Cygnus
and Vela regions will be discussed in companion papers.

</DOC>
<DOC>
<DOCNO> 11455 </DOCNO>
Metamagnetism and critical fluctuations in high quality single crystals


  We report the results of low temperature transport, specific heat and
magnetisation measurements on high quality single crystals of the bilayer
perovskite Sr3Ru2O7, which is a close relative of the unconventional
superconductor Sr2RuO4. Metamagnetism is observed, and transport and
thermodynamic evidence for associated critical fluctuations is presented. These
relatively unusual fluctuations might be pictured as variations in the Fermi
surface topography itself. No equivalent behaviour has been observed in the
metallic state of Sr2RuO4.

</DOC>
<DOC>
<DOCNO> 118072 </DOCNO>
Cancellation of GLONASS signals from Radio Astronomy Data


  Astronomers use the 1612 MHz OH spectral line emission as a unique window on
properties of evolved stars, galactic dynamics, and putative proto-planetary
disk systems around young stars. In recent years, experiments using this OH
line have become more difficult because radio telescopes are very sensitive to
transmissions from the GLONASS satellite system. The weak astronomical signals
are often undetectable in the presence of these unwanted human generated
signals. In this paper we demonstrate that GLONASS narrow band signals may be
removed using digital signal processing in a manner that is robust and
non-toxic to the weak astronomy signals, without using a reference antenna. We
present results using real astronomy data and outline the steps required to
implement useful systems on radio telescopes.

</DOC>
<DOC>
<DOCNO> 116551 </DOCNO>
Mesoscopic quantum coherence in an optical lattice


  We observe the quantum coherent dynamics of atomic spinor wavepackets in the
double well potentials of a far-off-resonance optical lattice. With appropriate
initial conditions the system Rabi oscillates between the left and right
localized states of the ground doublet, and at certain times the wavepacket
corresponds to a coherent superposition of these mesoscopically distinguishable
quantum states. The atom/optical double well potential is a flexible and
powerful system for further study of mesoscopic quantum coherence, quantum
control and the quantum/classical transition.

</DOC>
<DOC>
<DOCNO> 170198 </DOCNO>
Quantum Holographic Teleportation of Light Fields


  We describe a continious variable teleportation scheme that allows to
teleport the quantum state of distributed in space-time multimode
electromagnetic field. Our teleportation protocol uses the spatially-multimode
entangled Einstein-Podolsky-Rosen lihgt beams. We evaluate the "resolving
power" of teleportation in space-time and specify the degrees of freedom of
electromagnetic field whose quantum state can be effectively teleported. We
call this scheme "quantum holographic teleportation" because it can be
considered as an extension of conventional holography to quantum domain.

</DOC>
<DOC>
<DOCNO> 11733 </DOCNO>
Oscillations of Spherical and Cylindrical Shells


  We have found the complete spectrum and eigenstates for harmonic oscillations
of ideal spherical and cylindrical shells, both being infinitely thin. The
spectrum of the cylindrical shell has an infinite number of Goldstone modes
corresponding to folding deformations. This infrared catostrophe is overcome by
accounting for curvature-part of energy.

</DOC>
<DOC>
<DOCNO> 13295 </DOCNO>
Very large dielectric response of thin ferroelectric films with the dead


  We study the dielectric response of ferroelectric (FE) thin films with "dead"
dielectric layer at the interface with electrodes. The domain structure
inevitably forms in the FE film in presence of the dead layer. As a result, the
effective dielectric constant of the capacitor $\epsilon_{eff}$ increases
abruptly when the dead layer is thin and, consequently, the pattern of
180-degree domains becomes "soft". We compare the exact results for this
problem with the description in terms of a popular "capacitor" model, which is
shown to give qualitatively incorrect results. We relate the present results to
fatigue observed in thin ferroelectric films.

</DOC>
<DOC>
<DOCNO> 152559 </DOCNO>
Introduction to M(atrix) theory and noncommutative geometry


  Noncommutative geometry is based on an idea that an associative algebra can
be regarded as "an algebra of functions on a noncommutative space". The major
contribution to noncommutative geometry was made by A. Connes, who, in
particular, analyzed Yang-Mills theories on noncommutative spaces, using
important notions that were introduced in his papers (connection, Chern
character, etc). It was found recently that Yang-Mills theories on
noncommutative spaces appear naturally in string/M-theory; the notions and
results of noncommutative geometry were applied very successfully to the
problems of physics.
  In this paper we give a mostly self-contained review of some aspects of
M(atrix) theory, of Connes' noncommutative geometry and of applications of
noncommutative geometry to M(atrix) theory. The topics include introduction to
BFSS and IKKT matrix models, compactifications on noncommutative tori, a review
of basic notions of noncommutative geometry with a detailed discussion of
noncommutative tori, Morita equivalence and $SO(d,d|{\mathbb Z})$-duality, an
elementary discussion of instantons and noncommutative orbifolds. The review is
primarily intended for physicists who would like to learn some basic techniques
of noncommutative geometry and how they can be applied in string theory and to
mathematicians who would like to learn about some new problems arising in
theoretical physics.

</DOC>
<DOC>
<DOCNO> 150702 </DOCNO>
Dimensional Reduction, Gauged D=5 Supergravity and Brane Solutions


  The U(1) gauged version of the Strominger-Vafa five dimensional N=2
supergravity with one vector multiplet is obtained via dimensional reduction
from the N=1 ten dimensional supergavity. Using such explicit relation between
the gauged supergravity theory and ten dimensional supergravity, all known
solutions of the five dimensional theory can be lifted up to ten-dimensions.
The eleven dimensional solutions can also obtained by lifting the
ten-dimensional solutions.

</DOC>
<DOC>
<DOCNO> 101044 </DOCNO>
Embeddings of rearrangement invariant spaces that are not strictly


  We give partial answers to the following conjecture: the natural embedding of
a rearrangement invariant space E into L_1([0,1]) is strictly singular if and
only if G does not embed into E continuously, where G is the closure of the
simple functions in the Orlicz space L_Phi with Phi(x) = exp(x^2)-1.

</DOC>
<DOC>
<DOCNO> 152305 </DOCNO>
Universal Dynamics, a Unified Theory of Complex Systems. Emergence, Life


  A universal framework is proposed, where all laws are regularities of
relations between things or agents. Parts of the world at one or all times are
modeled as networks called SYSTEMS with a minimum of axiomatic properties. A
notion of locality is introduced by declaring some relations direct (or links).
Dynamics is composed of "atomic" constituents called mechanisms. They are
conditional actions of basic local structural transformations (``enzymes''):
indirect relations become direct (friend of friend becomes friend), links are
removed, objects copied. This defines a kind of universal chemistry.
  I show how to model basic life processes in a self contained fashion as a
kind of enzymatic computation. The framework also accommodates the gauge
theories of fundamental physics. Emergence creates new functionality by
cooperation - nonlocal phenomena arise out of local interactions. I explain how
this can be understood in a reductionist way by multiscale analysis (e.g.
renormalization group).

</DOC>
<DOC>
<DOCNO> 13370 </DOCNO>
Growing network with heritable connectivity of nodes


  We propose a model of a growing network, in which preferential linking is
combined with partial inheritance of connectivity (number of incoming links) of
individual nodes by new ones. The nontrivial version of this model is solved
exactly in the limit of a large network size. We demonstrate, that the
connectivity distribution depends on the network size, $t$, in a {\em
multifractal} fashion. When the size of the network tends to infinity, the
distribution behaves as $\sim q^{-\gamma}\ln q$, where $\gamma =\sqrt{2}$. For
the finite-size network, this behavior is observed for $1 \ll q \lesssim
\exp(\ln ^{1/2}t) $ but the multifractality is determined by the far wider
part, $1 \ll q \lesssim \sqrt t$, of the distribution function.

</DOC>
<DOC>
<DOCNO> 118073 </DOCNO>
A Broad 22 Microns Emission Feature in the Carina Nebula H II Region


  We report the detection of a broad 22 microns emission feature in the Carina
nebula H II region by the Infrared Space Observatory (ISO) Short Wavelength
Spectrometer. The feature shape is similar to that of the 22 microns emission
feature of newly synthesized dust observed in the Cassiopeia A supernova
remnant. This finding suggests that both of the features are arising from the
same carrier, and that supernovae are probably the dominant production source
of this new interstellar grain. A similar broad emission dust feature is also
found in the spectra of two starburst galaxies from the ISO archival data. This
new dust grain could be an abundant component of interstellar grains and can be
used to trace the supernova rate or star formation rate in external galaxies.
The existence of the broad 22 microns emission feature complicates the dust
model for starburst galaxies and must be taken into account correctly in the
derivation of dust color temperature. Mg protosilicate has been suggested as
the carrier of the 22 microns emission dust feature observed in Cassiopeia A.
The present results provide useful information in studies on chemical
composition and emission mechanism of the carrier.

</DOC>
<DOC>
<DOCNO> 39666 </DOCNO>
Four--Neutrino Oscillation Solutions of the Solar Neutrino Problem


  We present an analysis of the neutrino oscillation solutions of the solar
neutrino problem in the framework of four-neutrino mixing where a sterile
neutrino is added to the three standard ones. We perform a fit to the full data
set corresponding to the 825-day Super-Kamiokande data sample as well as to
Chlorine, GALLEX and SAGE and Kamiokande experiments. In our analysis we use
all measured total event rates as well as all Super-Kamiokande data on the
zenith angle dependence and the recoil electron energy spectrum. We consider
both transitions via the Mikheyev-Smirnov-Wolfenstein (MSW) mechanism as well
as oscillations in vacuum (just-so) and find the allowed solutions for
different values of the additional mixing angles. This framework permits
transitions into active or sterile neutrinos controlled by the additional
parameter $\cos^2(\vartheta_{23}) \cos^2(\vartheta_{24})$ . We discuss the
maximum allowed values of this additional mixing parameter for the different
solutions.

</DOC>
<DOC>
<DOCNO> 123235 </DOCNO>
Long-term Optical Variability of Radio-Selected Quasars from the FIRST


  We have obtained single-epoch optical photometry for 201 quasars, taken from
the FIRST Bright Quasar Survey, which span a wide range in radio loudness.
Comparison with the magnitudes of these objects on the POSS-I plates provides
by far the largest sample of long-term variability amplitudes for
radio-selected quasars yet produced. We find the quasars to be more variable in
the blue than in the red band, consistent with work on optically selected
samples. The previously noted trend of decreasing variability with increasing
optical luminosity applies only to radio-quiet objects. Furthermore, we do not
confirm a rise in variability amplitude with redshift, nor do we see any
dependence on radio flux or luminosity. The variability over a radio-optical
flux ratio range spanning a factor of 60,000 from radio-quiet to extreme
radio-loud objects is largely constant, although there is a suggestion of
greater variability in the extreme radio-loud objects. We demonstrate the
importance of Malmquist bias in variability studies, and develop a procedure to
correct for the bias in order to reveal the underlying variability properties
of the sample.

</DOC>
<DOC>
<DOCNO> 9254 </DOCNO>
NMR and Neutron Scattering Studies of Quasi One-Dimensional Magnet


  Magnetic properties of a quasi one-dimensional magnet CuV_2O_6 have been
studied by means of susceptibility measurement, NMR and powder neutron
diffraction. Cu^{2+} spins (S=1/2) order antiferromagnetically below 22.6 K,
and the saturation moment is about 0.70 \mu_{B} at 0 K. The magnetic structure
determined in the present study indicates that in CuV_2O_6 one-dimensional
antiferromagnetic spin chains are along [110], suggesting a dominant
antiferromagnetic exchange interaction between the next-nearest-neighbor spins
rather than the nearest-neighbor ones.

</DOC>
<DOC>
<DOCNO> 40067 </DOCNO>
Scalar Mesons and Chiral Symmetry


  It is the purpose of the present manuscript to emphasize those aspects that
make the scalar sector with vacuum quantum numbers rather unique. Chiral
symmetry is the basic tool for our study together with a resummation of Chiral
Perturbation Theory (CHPT) that stresses the role of unitarity but also allows
one to include explicit resonance fields and to match with the CHPT expansion
at low energies.

</DOC>
<DOC>
<DOCNO> 116364 </DOCNO>
On mixing times for stratified walks on the d-cube


  Using the electric and coupling approaches, we derive a series of results
concerning the mixing times for the stratified random walk on the d-cube,
inspired in the results of Chung and Graham (1997) Stratified random walks on
the n-cube.

</DOC>
<DOC>
<DOCNO> 169701 </DOCNO>
Cloning and quantum computation


  We discuss how quantum information distribution can improve the performance
of some quantum computation tasks. This distribution can be naturally
implemented with different types of quantum cloning procedures. We give two
examples of tasks for which cloning provides some enhancement in performance,
and briefly discuss possible extensions of the idea.

</DOC>
<DOC>
<DOCNO> 178843 </DOCNO>
On the relativistic origin of the kink effect in the chain of Pb


  We investigate the origin of the kink effect (KE) in the relativistic mean
field theory by transforming the single-particle Dirac equation into a
Schrodinger-like equation. It is found that relativistic self-consistent
effects as well as contributions from the rho meson determine the actual
structure of the KE. However, the spin-orbit force generated by the rho meson
has no significant influence on the KE.

</DOC>
<DOC>
<DOCNO> 14085 </DOCNO>
Asymmetric flux pinning in laterally nanostructured ferromagnetic /


  We investigated the pinning of flux lines in a superconducting film by a
regular array of magnetic antidots. The sample consists of a Co/Pt multilayer
with perpendicular magnetic anisotropy in which a regular pattern of submicron
holes is introduced and which is covered by a type-II superconducting Pb film.
The resulting ferromagnetic/superconducting heterostructure shows a pronounced
asymmetric magnetization curve with respect to the field polarity. This
asymmetry clearly demonstrates that the magnetic contribution dominates the
pinning potential imposed by the magnetic antidots on the superconducting film.

</DOC>
<DOC>
<DOCNO> 118827 </DOCNO>
Cicrumnuclear Supernova Remnants and HII Regions in NGC 253


  Archival VLA data has been used to produce arcsecond-resolution 6- and 20-cm
images of the region surrounding the nuclear 200-pc (~15") starburst in NGC
253. Twenty-two discrete sources stronger than 0.4 mJy have been detected
within ~2 kpc (~3') of the galaxy nucleus; almost all these sources must be
associated with the galaxy. None of the radio sources coincides with a detected
X-ray binary, so they appear to be due to supernova remnants and H II regions.
The region outside the central starburst has a derived radio supernova rate of
<~0.1/yr, and may account for at least 20% of the recent star formation in NGC
253. Most of the newly identified sources have steep, nonthermal radio spectra,
but several relatively strong thermal sources also exist, containing the
equivalent of tens of O5 stars. These stars are spread over tens of parsecs,
and are embedded in regions having average ionized gas densities of
20-200/cm^3, much lower than in the most active nuclear star-forming regions in
NGC 253 or in the super star clusters seen in other galaxies. The strongest
region of thermal emission coincides with a highly reddened area seen at
near-infrared wavelengths, possibly containing optically obscured H II regions.

</DOC>
<DOC>
<DOCNO> 10188 </DOCNO>
Vortex Matter and its Phase Transitions


  The mixed state of type II superconductors has magnetic flux penetrating the
sample in the form of vortices, with each vortex carrying an identical quantum
of flux. These vortices generally form a triangular lattice under weak mutually
repulsive forces; the lattice spacing can be easily varied over many orders of
magnitude by varying the external magnetic field. The elastic moduli of this
lattice are small and this soft vortex matter can undergo phase transitions
like normal matter, but with thermal fluctuations and underlying defects
playing an important role. We discuss experimental studies on vortex matter
phase transitions, with some emphasis on DC magnetisation measurements
investigating the nature of the phase transition.

</DOC>
<DOC>
<DOCNO> 174608 </DOCNO>
Thin Ice Target for $^{16}$O(p,p') experiment


  A windowless and self-supporting ice target is described. An ice sheet with a
thickness of 29.7 mg/cm$^2$ cooled by liquid nitrogen was placed at the target
position of a magnetic spectrometer and worked stably in the $^{16}$O$(p,p')$
experiment at $E_{p}=392$ MeV. Background-free spectra were obtained.

</DOC>
<DOC>
<DOCNO> 118043 </DOCNO>
The Polytropic Equation of State of Interstellar Gas Clouds


  Models are presented for the polytropic equation of state of
self-gravitating, quiescent interstellar gas clouds. A detailed analysis,
including chemistry, thermal balance, and radiative transfer, is performed for
the physical state of the gas as a function of density, metallicity, velocity
field, and background radiation field. It is found that the stiffness of the
equation of state strongly depends on all these physical parameters, and the
adiabatic index varies between 0.2-1.4. The implications for star formation, in
particular at high redshift and in starburst galaxies, and the initial stellar
mass function are discussed.

</DOC>
<DOC>
<DOCNO> 85198 </DOCNO>
A data-analysis strategy for detecting gravitational-wave signals from


  A data-analysis strategy based on the maximum-likelihood method (MLM) is
presented for the detection of gravitational waves from inspiraling compact
binaries with a network of laser-interferometric detectors having arbitrary
orientations and arbitrary locations around the globe. The MLM is based on the
network likelihood ratio (LR), which is a function of eight signal-parameters
that determine the Newtonian inspiral waveform. In the MLM-based strategy, the
LR must be maximized over all of these parameters. Here, we show that it is
possible to maximize it analytically over four of the eight parameters.
Maximization over a fifth parameter, the time of arrival, is handled most
efficiently by using the Fast-Fourier-Transform algorithm. This allows us to
scan the parameter space continuously over these five parameters and also cuts
down substantially on the computational costs. Maximization of the LR over the
remaining three parameters is handled numerically. This includes the
construction of a bank of templates on this reduced parameter space. After
obtaining the network statistic, we first discuss `idealized' networks with all
the detectors having a common noise curve for simplicity. Such an exercise
nevertheless yields useful estimates about computational costs, and also tests
the formalism developed here. We then consider realistic cases of networks
comprising of the LIGO and VIRGO detectors: These include two-detector
networks, which pair up the two LIGOs or VIRGO with one of the LIGOs, and the
three-detector network that includes VIRGO and both the LIGOs. For these
networks we present the computational speed requirements, network
sensitivities, and source-direction resolutions.

</DOC>
<DOC>
<DOCNO> 11684 </DOCNO>
Electronic Structure and Fermiology of Sr$_3$Ru$_2$O$_7$


  The electronic structure of layered Sr$_{3}$Ru$_{2}$O$_{7}$ in its
orthorhombic structure is investigated using density functional calculations.
The band structure near the Fermi energy, consists of Ru $% t_{2g}$ states
hybridized with O $p$ orbitals. The $yz$ and $xz$ bands, which are largely
responsible for the nesting related antiferromagnetic spin fluctuations in
Sr$_{2}$RuO$_{4}$ split pairwise into even and odd combinations due to the
interlayer coupling reducing the strength of the nesting. The $xy$ bands show
much less interplanar coupling as expected, and also less $c$-axis dispersion,
so that the barrel like sections are largely intact compared to the single
layer material. The zone folding due to orthorhombicity yields small
cylindrical lens shaped Fermi surfaces centered at the midpoints of the former
tetragonal $\Gamma -X$ lines. Fixed spin moment calculations indicate that
tetragonal Sr$_{3}$Ru$_{2}$O$_{7}$ is borderline ferromagnetic but that
orthorhombicity favors magnetism via a substantial magnetoelastic coupling.
These results are related to experimental observations particularly in regard
to magnetic properties.

</DOC>
<DOC>
<DOCNO> 118553 </DOCNO>
On the Radii of Close-in Giant Planets


  The recent discovery that the close-in extrasolar giant planet, HD209458b,
transits its star has provided a first-of-its-kind measurement of the planet's
radius and mass. In addition, there is a provocative detection of the light
reflected off of the giant planet, $\tau$ Boo b. Including the effects of
stellar irradiation, we estimate the general behavior of radius/age
trajectories for such planets and interpret the large measured radii of
HD209458b and $\tau$ Boo b in that context. We find that HD209458b must be a
hydrogen-rich gas giant. Furthermore, the large radius of close-in gas giant is
not due to the thermal expansion of its atmosphere, but to the high residual
entropy that remains throughout its bulk by dint of its early proximity to a
luminous primary. The large stellar flux does not inflate the planet, but
retards its otherwise inexorable contraction from a more extended configuration
at birth. This implies either that such a planet was formed near its current
orbital distance or that it migrated in from larger distances ($\geq$0.5 A.U.),
no later than a few times $10^7$ years of birth.

</DOC>
<DOC>
<DOCNO> 9301 </DOCNO>
Doubly Enhanced Skyrmions in $\nu =2$ Bilayer Quantum Hall States


  By tilting the samples in the magnetic field, we measured and compared the
Skyrmion excitations in the bilayer quantum Hall (QH) state at the Landau-level
filling factor $\nu =2$ and in the monolayer QH state at $\nu =1$. The observed
number of flipped spins is $N_s=14$ in the bilayer system with a large
tunneling gap, and $N_s=7$ in the bilayer system with a small tunneling gap,
while it is $N_s=7$ in the monolayer system. The difference is interpreted due
to the interlayer exchange interaction. Moreover, we have observed seemingly
preferred numbers $N_s=14,7,1$ for the flipped spins by tilting bilayer
samples.

</DOC>
<DOC>
<DOCNO> 69703 </DOCNO>
Inclusive and exclusive decays of doubly heavy baryons


  In this paper we give a short review of the recently obtained results on
inclusive and exclusive decays of doubly heavy baryons.

</DOC>
<DOC>
<DOCNO> 7645 </DOCNO>
Influence of phase-sensitive interaction on the decoherence process in


  The character of the interaction between an impurity vibrational mode and a
heat bath leads to certain peculiarities in the relaxational dynamics of the
excited states. We derive a non-Markovian equation of motion for the reduced
density matrix of this system which is valid for initial, intermediate and
kinetic stages of the relaxation. The linear phase-sensitive character of the
interaction ensures the ultrafast disappearance of the quantum interference of
the initially superpositional state and the effect of classical squeezing of
the initially coherent state. On the other hand, the second power interaction
induces a partial conservation of the quantum interference.

</DOC>
<DOC>
<DOCNO> 11683 </DOCNO>
Effective field theory for the bulk and edge states of quantum Hall


  We present an effective theory for the bulk Fractional Quantum Hall states in
spin-polarized bilayer and spin-1/2 single layer two-dimensional electron gases
(2DEG) in high magnetic fields consistent with the requirement of global gauge
invariance on systems with periodic boundary conditions. We derive the theory
for the edge states that follows naturally from this bulk theory. We find that
the minimal effective theory contains two propagating edge modes that carry
charge and energy, and two non-propagating topological modes responsible for
the statistics of the excitations. We give a detailed description of the
effective theory for the spin-singlet states, the symmetric bilayer states and
for the $(m,m,m)$ states. We calculate explicitly, for a number of cases of
interest, the operators that create the elementary excitations, their bound
states, and the electron. We also discuss the scaling behavior of the tunneling
conductances in different situations: internal tunneling, tunneling between
identical edges and tunneling into a FQH state from a Fermi liquid.

</DOC>
<DOC>
<DOCNO> 9923 </DOCNO>
Formation of Pairing Fields in Resonantly Coupled Atomic and Molecular


  In this paper, we show that pair-correlations may play an important role in
the quantum statistical properties of a Bose-Einstein condensed gas composed of
an atomic field resonantly coupled with a corresponding field of molecular
dimers. Specifically, pair-correlations in this system can dramatically modify
the coherent and incoherent transfer between the atomic and molecular fields.

</DOC>
<DOC>
<DOCNO> 123307 </DOCNO>
The halo model and numerical simulations


  Recently there has been a lot of attention focussed on a virialized
halo-based approach to understanding the properties of the matter and galaxy
power spectrum. A key ingredient in this model is the number and distribution
of galaxies within dark matter halos as a function of mass. This quantity has
been predicted from semi-analytic modeling and from fits to observational data.
Here we present predictions for the occupation number and spatial distribution
of sub-halos based on a high-resolution hydrodynamical simulation including
cooling, star-formation and feedback.

</DOC>
<DOC>
<DOCNO> 85584 </DOCNO>
Effect of spins on the quantum entropy of black holes


  By using the Newman-Penrose formalism and 't Hooft brick-wall model, the
quantum entropies of the Kerr-Newman black hole due to the Dirac and
electromagnetic fields are calculated and the effects of the spins of the
photons and Dirac particles on the entropies are investigated. It is shown that
the entropies depend only on the square of the spins of the particles and the
contribution of the spins is dependent on the rotation of the black hole,
except that different fields obey different statistics.

</DOC>
<DOC>
<DOCNO> 8821 </DOCNO>
Vortex in a d-wave superconductor at low temperatures


  A systematic perturbation theory is developed to describe the magnetic
field-induced subdominant $s$- and $d_{xy}$-wave order parameters in the mixed
state of a $d_{x^2-y^2}$-wave superconductor, enabling us to obtain, within
weak-coupling BCS theory, analytic results for the free energy of a d-wave
superconductor in an applied magnetic field $H_{c1}\ltsim H\ll H_{c2}$ from
$T_c$ down to very low temperatures. Known results for a single isolated vortex
in the Ginzburg-Landau regime are recovered, and the behavior at low
temperatures for the subdominant component is shown to be qualitatively
different. In the case of subdominant $d_{xy}$ pair component, superfluid
velocity gradients and an orbital Zeeman effect are shown to compete in
determining the vortex state, but for realistic field strengths the latter
appears to be irrelevant. On this basis, we argue that recent predictions of a
low-temperature phase transition in connection with recent thermal conductivity
measurements are unlikely to be correct.

</DOC>
<DOC>
<DOCNO> 169876 </DOCNO>
Fundamental bounds on quantum measurements with a mixed apparatus


  We consider the apparatus in a quantum measurement process to be in a mixed
state. We propose a simple upper bound on the probability of correctly
distinguishing any number of mixed states. We use this to derive fundamental
bounds on the efficiency of a measurement in terms of the temperature of the
apparatus.

</DOC>
<DOC>
<DOCNO> 120920 </DOCNO>
Effects of dust extinction on optical spectroscopic properties for


  Recent observational studies on galaxies in distant clusters discovered a
significant fraction of possible dusty starburst galaxies with the so-called
`e(a)' spectra that are characterized by strong H$\delta$ absorption and
relatively modest [OII] emission. We numerically investigate spectroscopic and
photometric evolution of dusty starburst galaxies in order to clarify the
origin of the e(a) spectra. We found that if a young starburst population is
preferentially obscured by dust than an old one in a dusty starburst galaxy,
the galaxy shows e(a) spectrum. It is therefore confirmed that the selective
dust extinction, which is first suggested by Poggianti & Wu (2000) and means
the strongest dust extinction for the youngest stellar population among stellar
populations with different ages, is critically important to reproduce
quantitatively the observed e(a) spectra for the first time in the present
numerical study. We furthermore discuss what physical process is closely
associated with this selective dust extinction in cluster environment.

</DOC>
<DOC>
<DOCNO> 117117 </DOCNO>
The Particle Model


  This paper introduces the Particle Model. The Particle Model and the Standard
Model have many similarities, but also significantly differ from each other in
terms of their fundamental physics and interpretation. Quarks should not be
viewed as particles but as reduction centers within a chaotic soliton
structure. The mass of individual quarks becomes meaningless. Within a
particle, reduction centers can only have two possible phases (+ and -) that
correspond with the two possible charges for particles with a single reduction
center (electrons, muons and tau particles). For particles with 2 or 3
reduction centers (mesons and baryons respectively) charge can be understood as
a consequence of the reduction center phase and reduction center spin vortex
coupling. The internal structure of particles can be derived from known
experimental results and the assumed existence of reduction center spin
coupling. From the internal structure of the proton and neutron it can be
derived that only one of the three reduction centers effectively contributes to
the externally observed spin. The so-called phase-charge law is derived. The
notion of fractional charge for reduction centers can consistently be defined
by rewriting the phase-charge law. The fractional charges are +/-1/3 and +/-
2/3 for baryons and +/- 1/2 for mesons. The concepts of strangeness and isospin
can formally be defined and turn out to be connected with reduction center
phase and charge. The relation Q=I+(B+S)/2 can be derived from the definitions
of strangeness and isospin and the phase-charge law. The symmetry of particle
multiplets is a consequence of the definitions of strangeness and isospin and
seems to have no physical significance.

</DOC>
<DOC>
<DOCNO> 69308 </DOCNO>
Discrete Flavor Symmetries and Mass Matrix Textures


  We show how introducing discrete Abelian flavor symmetries can produce
texture zeros in the fermion mass matrices, while preserving the correct
relationships with the low-energy data on quark and lepton masses. We outline a
procedure for defining texture zeros as suppressed entries in Yukawa matrices.
These texture zeros can account for the coexistence of the observed large
mixing in atmospheric neutrino oscillations with a hierarchy in the neutrino
masses, and offer the possibility of alignment of the quark and squark mass
matrices, and thus giving a solution to the supersymmetric flavor problem. A
requirement that the flavor symmetry commutes with the SU(5) grand unified
group can be used to explain the lepton mass hierarchies as well as the
neutrino parameters, including the large mixing observed in the atmospheric
neutrino data. We present one such model that yields a large atmospheric
neutrino mixing angle, as well as a solar neutrino mixing angle of order
$\lambda \simeq 0.22$.

</DOC>
<DOC>
<DOCNO> 11910 </DOCNO>
Effect of Doping-induced Disorder on Transition Temperature in High


  We study the effect of disorder induced by doping on the transition
temperature in high $T_c$ cuprates. Since the impurity lies between the CuO$_2$
planes, the momentum transfer is restricted by small angle with a range of
order of $1/(d k_F)$, where $k_F$ is the Fermi momentum and $d$ is the distance
between the plane and the impurity. We find that the leading correction on the
transition temperature in this case is in cubic order of $1/(d k_F)$, while the
single particle scattering rate is linearly proportional to $1/(d k_F)$.
Therefore, we conclude that the disorder induced by doping has rather small
effect on $T_c$, while it could give large single particle scattering rate. We
find that the reduction of $T_c$ is about $3-10 %$, using the single particle
scattering rate ($150-450 K$) observed in the recent angle-resolved-
photoemission-spectroscopy data on optimally doped Bi2212. The consequences of
the small angle scattering in other physical quantities such as transport are
also discussed.

</DOC>
<DOC>
<DOCNO> 84642 </DOCNO>
Fast and Accurate Computation Tools for Gravitational Waveforms from


  The relevance of orbital eccentricity in the detection of gravitational
radiation from (steady state) binary stars is emphasized. Computationnally
effective fast and accurate)tools for constructing gravitational wave templates
from binary stars with any orbital eccentricity are introduced, including tight
estimation criteria of the pertinent truncation and approximation errors.

</DOC>
<DOC>
<DOCNO> 118122 </DOCNO>
The Merger Rate to Redshift One from Kinematic Pairs: Caltech Faint


  The rate of mass accumulation due to galaxy merging depends on the mass,
density, and velocity distribution of galaxies in the near neighborhood of a
host galaxy. The fractional luminosity in kinematic pairs combines all of these
effects in a single estimator which is relatively insensitive to population
evolution. Here we use a k-corrected and evolution compensated volume-limited
sample drawing about 300 redshifts from CFGRS and 3000 from CNOC2 to measure
the rate and redshift evolution of merging. We identify kinematic pairs with
projected separations less than either 50 or 100 \hkpc and rest-frame velocity
differences of less than 1000\kms. The fractional luminosity in pairs is
modeled as f_L(Delta v,r_p,M_r^{ke})(1+z)^{m_L} where [f_L,m_L] are
[0.14+/-0.07,0+/-1.4] and [0.37+/-0.7,0.1+/-0.5] for r_p<= 50 and 100\hkpc,
respectively (Omega_M=0.2, Omega_Lambda=0.8). The value of m_L is about 0.6
larger if Lambda=0. To convert these redshift space statistics to a merger rate
we use the data to derive a conversion factor to physical space pair density, a
merger probability and a mean in-spiral time. The resulting mass accretion rate
per galaxy (M_1,M_2>= 0.2 M*) is 0.02+/-0.01(1+z)^{0.1+/-0.5} M*~Gyr^{-1}.
Present day high-luminosity galaxies therefore have accreted approximately
0.15M* of their mass over the approximately 7 Gyr to redshift one. (abridged)

</DOC>
<DOC>
<DOCNO> 68576 </DOCNO>
Reconciling $G_A/G_V, <r_n^2>$ and $\mu_{p,n}$ in Chiral Quark Model


  The spin polarization functions $(\Delta u, ~\Delta d, ~\Delta s)$ for proton
are calculated in the chiral quark model ($\chi$QM) with SU(3) symmetry
breaking as well as configuration mixing generated by one gluon exchange forces
for the NMC and the most recent E866 data. Besides reproducing the spin
polarization functions $\Delta u,\Delta d, \Delta s$ as well as $G_A/G_V$, it
can accomodate nucleon magnetic moments and neutron charge radius as well, thus
resolving the compatibility problem of these parameters which could not be
achieved in constituent quark models.

</DOC>
<DOC>
<DOCNO> 117844 </DOCNO>
The Number of Publications Used As A Metric of the NOAO WIYN Queue


  We use the number of papers published in 1998 and 1999 to test the hypothesis
that the queue observing mode at WIYN leads to a significantly higher
scientific throughput than classical mode observing. We use the papers
published from the 4-m, and papers published from the non-queue WIYN time as
controls, requiring only that the data be obtained after 1996 August 1, at
which time the WIYN queue was in its third full semester of operation, and the
WIYN instruments functional and stable. The number of papers published from the
queue data is actually 1.5 times smaller (on a per night basis) than from the
4-m, and roughly comparable to (but lower than) the number published from
non-queue WIYN time. Thus neither comparison offers any support for the
hypothesis that queue leads to a higher scientific throughput. The number of
papers is relatively small, but the statistics are sufficiently robust to
reject the possibility that queue observing at WIYN leads to a factor of 1.5
enhancement in publication rate with a 99.3% confidence in comparison to the
4-m, and with an 89.9% confidence in comparison with non-queue WIYN time. We
consider several explanations, and urge other observatories planning to employ
the queue mode include some controls to provide an objective evaluation of its
success.

</DOC>
<DOC>
<DOCNO> 9252 </DOCNO>
Large Magnetic-Field-Induced Strains in Ni-Mn-Ga Alloys due to


  A polycrystalline and single-crystal samples of near-stoichiometric Ni2MnGa
alloys have been investigated. It was confirmed that martensite short
crystallographic axis (c-axis) is the easy axis of magnetization. The
reversible reorientation of the easy magnetization direction of martensite
samples after 5% compression is found. The same reversible reorientation of the
easy magnetization direction under applied magnetic field occurs in the
single-crystal samples. The field-induced reorientation of the easy
magnetization direction is accompanied with more than 4% of sample's dimension
change. About the same value of the field-induced strains can be obtained for
polycrystalline samples after appropriate thermo-mechanical treatment.

</DOC>
<DOC>
<DOCNO> 71863 </DOCNO>
Static dilaton solutions and singularities in six dimensional warped


  Static solutions with a bulk dilaton are derived in the context of six
dimensional warped compactification. In the string frame, exponentially
decreasing warp factors are identified with critical points of the low energy
$\beta$-functions truncated at a given order in the string tension corrections.
The stability of the critical points is discussed in the case of the first
string tension correction. The singularity properties of the obtained solutions
are analyzed and illustrative numerical examples are provided.

</DOC>
<DOC>
<DOCNO> 169733 </DOCNO>
Double jumps and transition rates for two dipole-interacting atoms


  Cooperative effects in the fluorescence of two dipole-interacting atoms, with
macroscopic quantum jumps (light and dark periods), are investigated. The
transition rates between different intensity periods are calculated in closed
form and are used to determine the rates of double jumps between periods of
double intensity and dark periods, the mean duration of the three intensity
periods and the mean rate of their occurrence. We predict, to our knowledge for
the first time, cooperative effects for double jumps, for atomic distances from
one and to ten wave lengths of the strong transition. The double jump rate, as
a function of the atomic distance, can show oscillations of up to 30% at
distances of about a wave length, and oscillations are still noticeable at a
distance of ten wave lengths. The cooperative effects of the quantities and
their characteristic behavior turn out to be strongly dependent on the laser
detuning.

</DOC>
<DOC>
<DOCNO> 170367 </DOCNO>
Numerical Constructions of Perturbation Series in Quantum Mechanics


  A few modified textbook Rayleigh-Schr\"{o}dinger perturbative representations
of bound states are reviewed. They were all inspired by an adaptive re-split of
the Hamiltonian, using nonstandard bases and the flexibility of normalization
of the wave functions.

</DOC>
<DOC>
<DOCNO> 101232 </DOCNO>
Rigidity, unitary representations of semisimple groups, and fundamental


  The article establishes a long list of rigidity properties of lattices in G
= SO(n,1) with n>=3 and G = SU(n,1) with n>=2 that are analogous to
superrigidity of lattices in higher-rank Lie groups. The arguments are set in
the context of strongly L^p unitary representations of G.

</DOC>
<DOC>
<DOCNO> 117832 </DOCNO>
A broadband X-ray view of NGC4945


  We present the results of a BeppoSAX observation of the nearby spiral galaxy
NGC4945 in the 0.1-200 keV energy band. The nuclear X-ray emission emerges
above ~7 keV, through an absorber with column density N_H ~ a few 10^24/cm/cm.
Its remarkable variability (doubling/halving timescale ~10^4 s) is not
associated with any appreciable spectral changes, ruling out variations of the
interposed absorber or changes in the primary continuum shape. The intense iron
K-ALPHA fluorescent emission line is likely to be produced by the same nuclear
absorbing matter. Our estimate of the intrinsic nuclear power suggests that the
active nucleus dominates the bolometric energy output of NGC4945, if its
nucleus has a typical quasar L_X/L(bol) ratio. This supports the idea that
X-rays are the best energy band to search for absorbed AGN. The 0.1-5 keV
emission is extended along the plane of the galaxy, and most likely due to a
population of unresolved binaries, as believed to happen in several early-type
galaxies. Alternatively, hot gas associated with a starburst-driven superwind
outflow could substantially contribute to the extended emission above 1 keV.

</DOC>
<DOC>
<DOCNO> 12562 </DOCNO>
Classical generalized constant coupling model for geometrically


  A generalized constant coupling approximation for classical geometrically
frustrated antiferromagnets is presented. Starting from a frustrated unit we
introduce the interactions with the surrounding units in terms of an internal
effective field which is fixed by a self consistency condition. Results for the
magnetic susceptibility and specific heat are compared with Monte Carlo data
for the classical Heisenberg model for the pyrochlore and kagome lattices. The
predictions for the susceptibility are found to be essentially exact, and the
corresponding predictions for the specific heat are found to be in very good
agreement with the Monte Carlo results.

</DOC>
<DOC>
<DOCNO> 68820 </DOCNO>
Cosmic Magnetic Fields from Particle Physics


  I review a number of particle-physics models that lead to the creation of
magnetic fields in the early universe and address the complex problem of
evolving such primordial magnetic fields into the fields observed today.
Implications for future observations of the Cosmic Microwave Background (CMB)
are briefly discussed.

</DOC>
<DOC>
<DOCNO> 151340 </DOCNO>
Actions and symmetries of NSR superstrings and D-strings


  We present all NSR superstring and super-D-string actions invariant under a
set of prescribed gauge transformations, and characterize completely their
global symmetries. In particular we obtain locally supersymmetric Born-Infeld
actions on general backgrounds in a formulation with extra target space
dimensions. The nontrivial global symmetries of the superstring actions
correspond to isometries of the background, whereas super-D-string actions can
have additional symmetries acting nontrivially also on the coordinates of the
extra dimensions.

</DOC>
<DOC>
<DOCNO> 85046 </DOCNO>
Sensitivity of a VIRGO pair to stochastic GW backgrounds


  The sensitivity of a pair of VIRGO interferometers to gravitational waves
backgrounds (GW) of cosmological origin is analyzed for the cases of maximal
and minimal overlap of the two detectors. The improvements in the detectability
prospects of scale-invariant and non-scale-invariant logarithmic energy spectra
of relic GW are discussed.

</DOC>
<DOC>
<DOCNO> 101669 </DOCNO>
Franklin's argument proves an identity of Zagier


  Recently Zagier proved a remarkable q-series identity. We show that this
identity can also be proved by modifying Franklin's classical proof of Euler's
pentagonal number theorem.

</DOC>
<DOC>
<DOCNO> 151153 </DOCNO>
Spectral functions in mathematics and physics


  Spectral functions relevant in the context of quantum field theory under the
influence of spherically symmetric external conditions are analysed. Examples
comprise heat-kernels, determinants and spectral sums needed for the analysis
of Casimir energies. First, we summarize that a convenient way of handling them
is to use the associated zeta function. A way to determine all its needed
properties is derived. Using the connection with the mentioned spectral
functions, we provide: i.) a method for the calculation of heat-kernel
coefficients of Laplace-like operators on Riemannian manifolds with smooth
boundaries and ii.) an analysis of vacuum energies in the presence of
spherically symmetric boundaries and external background potentials.

</DOC>
<DOC>
<DOCNO> 100618 </DOCNO>
Incidence relations among the Schubert cells of equivariant Hilbert


  Let HH_{ab}(H) be the equivariant Hilbert scheme parametrizing the zero
dimensional subschemes of the affine plane k^2, fixed under the one dimensional
torus T_{ab}={(t^{-b},t^a), t\in k^*} and whose Hilbert function is H. This
Hilbert scheme admits a natural stratification in Schubert cells which extends
the notion of Schubert cells on Grassmannians. However, the incidence relations
between the cells become more complicated than in the case of Grassmannians. In
this paper, we give a necessary condition for the closure of a cell to meet
another cell. In the particular case of Grassmannians, it coincides with the
well known necessary and sufficient incidence condition. There is no known
example showing that the condition wouldn't be sufficient.

</DOC>
<DOC>
<DOCNO> 121994 </DOCNO>
Ultra-Lithium-Deficient Halo Stars and Blue Stragglers: A Common Origin?


  We present data for four ultra-Li-deficient, warm, halo stars. The Li
deficiency of two of these is a new discovery. Three of the four stars have
effective temperatures Teff ~ 6300 K, in contrast to previously known
Li-deficient halo stars which spanned the temperature range of the Spite
Plateau. In this paper we propose that these, and previously known
ultra-Li-deficient halo stars, may have had their surface lithium abundances
reduced by the same mechanism as produces halo field blue stragglers. Even
though these stars have yet to reveal themselves as blue stragglers, they might
be regarded as "blue-stragglers-to-be." In our proposed scenario, the surface
abundance of Li in these stars could be destroyed (a) during the normal
pre-main-sequence single star evolution of their low mass precursors, (b)
during the post-main-sequence evolution of a evolved mass donor, and/or (c) via
mixing during a mass-transfer event or stellar merger. The warmest Li-deficient
stars at the turnoff would be regarded as emerging "canonical" blue stragglers,
whereas cooler ones represent sub-turnoff-mass "blue-stragglers-to-be." The
latter are presently hidden on the main sequence, Li depletion being possibly
the clearest signature of their past history and future significance.
Eventually, the main sequence turnoff will reach down to their mass, exposing
those Li-depleted stars as canonical blue stragglers when normal stars of that
mass evolve away. Arguing against this unified view is the observation that the
three Li-depleted stars at Teff ~ 6300 K are all binaries, whereas very few of
the cooler systems show evidence for binarity; it is thus possible that two
separate mechanisms are responsible for the production of Li-deficient
main-sequence halo stars.

</DOC>
<DOC>
<DOCNO> 40224 </DOCNO>
Future Kaon Programs at BNL and FNAL


  Future kaon decay programs at BNL and FNAL are discussed. The primary focus
of these programs is the measurement of the golden modes, the neutral and
charged kaon decays to a pion and two neutrinos. The observation of the charged
mode by E787 at BNL is the first step in a series of measurements which will
completely determine the unitarity triangle within the kaon system.

</DOC>
<DOC>
<DOCNO> 70350 </DOCNO>
Solar Neutrino Solutions in Non-Abelian Flavor Symmetry


  We have studied the large mixing angle MSW solution for the solar neutrinos
in the non-abelian flavor symmetry. We predict the MNS mixing matrix taking
account of the symmetry breakings.

</DOC>
<DOC>
<DOCNO> 8705 </DOCNO>
Statistical properties of eigenstates in three-dimensional mesoscopic


  The statistics of eigenfunction amplitudes are studied in mesoscopic
disordered electron systems of finite size. The exact eigenspectrum and
eigenstates are obtained by solving numerically Anderson Hamiltonian on a
three-dimensional lattice for different strengths of disorder introduced either
in the potential on-site energy (``diagonal'') or in the hopping integral
(``off-diagonal''). The samples are characterized by the exact zero-temperature
conductance computed using real-space Green function technique and related
Landauer-type formula. The comparison of eigenstate statistics in two models of
disorder shows sample-specific details which are not fully taken into account
by the conductance, shape of the sample and dimensionality. The wave function
amplitude distributions for the states belonging to different transport regimes
within the same model are contrasted with each other as well as with universal
predictions of random matrix theory valid in the infinite conductance limit.

</DOC>
<DOC>
<DOCNO> 69748 </DOCNO>
Impact of Hadronic Axions on Black Hole Accretion Discs and Neutron


  We re-examine the possibility of an astrophysically allowed KSVZ-type axion
that has a strongly suppressed coupling to photons. We then investigate the
impact of such ''hadronic axions'' on two classes of astrophysical objects:
black hole accretion disc (BHAD) based gamma-ray bursts and isolated
neutron-stars. Although our results are sensitive to details of the underlying
models, we show that hadronic axions could in principle play an important role
in the evolution of gamma-ray bursts and in the cooling behaviour of neutron
stars.

</DOC>
<DOC>
<DOCNO> 178949 </DOCNO>
Mid-rapidity charge distribution in peripheral heavy ion collisions


  The charge density distribution with respect to the velocity of matter
produced in peripheral heavy ion reactions around Fermi energy is investigated.
The experimental finding of enhancement of mid-rapidity matter shows the
necessity to include correlations beyond BUU which was performed in the
framework of nonlocal kinetic theory. Different theoretical improvements are
discussed. While the in-medium cross section changes the number of collisions,
it leaves the transferred energy almost unchanged. In contrast the nonlocal
scenario changes the energy transferred during collisions and leads to an
enhancement of mid-rapidity matter. The renormalisation of quasiparticle
energies can be included in nonlocal scenarios and leads to a further
enhancement of mid-rapidity matter distribution. This renormalisation is
accompanied by a dynamical softening of the equation of state seen in longer
oscillation periods of the excited compressional collective mode. We propose to
include quasiparticle renormalisation by using the Pauli-rejected collisions
which circumvent the problem of backflows in Landau theory. Using the maximum
relative velocity of projectile and target like fragments we associate
experimental events with impact parameters of the simulations. For peripheral
collisions we find a reasonable agreement between experiment and theory. For
more central collisions, the velocity damping is higher in one-body simulations
than observed experimentally, because of missing cluster formations in the
kinetic theory used.

</DOC>
<DOC>
<DOCNO> 69141 </DOCNO>
Constraints on a Parity-even/Time-Reversal-odd Interaction


  Time-Reversal-Invariance non-conservation has for the first time been
unequivocally demonstrated in a direct measurement, one of the results of the
CPLEAR experiment. What is the situation then with regard to
time-reversal-invariance non-conservation in systems other than the neutral
kaon system? Two classes of tests of time-reversal-invariance need to be
distinguished: the first one deals with parity violating
(P-odd)/time-reversal-invariance non-conserving (T-odd) interactions, while the
second one deals with P-even/T-odd interactions (assuming CPT conservation this
implies C-conjugation non-conservation). Limits on a P-odd/T-odd interaction
follow from measurements of the electric dipole moment of the neutron. This in
turn provides a limit on a P-odd/T-odd pion-nucleon coupling constant which is
10^-4 times the weak interaction strength. Limits on a P-even/T-odd interaction
are much less stringent. The better constraint stems also from the measurement
of the electric dipole moment of the neutron. Of all the other tests,
measurements of charge-symmetry breaking in neutron-proton elastic scattering
provide the next better constraint. The latter experiments were performed at
TRIUMF (at 477 and 347 MeV) and at IUCF (at 183 MeV). Weak decay experiments
(the transverse polarization of the muon in K+ -> pi0 mu+ nu and the transverse
polarization of the positrons in polarized muon decay) have the potential to
provide comparable or possibly better constraints.

</DOC>
<DOC>
<DOCNO> 174602 </DOCNO>
A complete set of total cross sections for imaginary parts of nd forward


  In the neutron-deuteron scattering, four total cross sections are shown to
form a complete set for the determination of the imaginary parts of the forward
amplitudes because of the optical theorem. The amplitudes are decomposed into
scalar and tensor ones in the spin space. Contributions of three-nucleon forces
(3NF) to these amplitudes are studied, by the Faddeev calculation, which
predicts significant tensor effects of the 3NF.

</DOC>
<DOC>
<DOCNO> 118483 </DOCNO>
Eigenvector Sky Subtraction


  We develop a new method for estimating and removing the spectrum of the sky
from deep spectroscopic observations; our method does not rely on simultaneous
measurement of the sky spectrum with the object spectrum. The technique is
based on the iterative subtraction of continuum estimates and Eigenvector sky
models derived from Singular Value Decompositions (SVD) of sky spectra, and sky
spectra residuals. Using simulated data derived from small telescope
observations we demonstrate that the method is effective for faint objects on
large telescopes. We discuss simple methods to combine our new technique with
the simultaneous measurement of sky to obtain sky subtraction very near the
Poisson limit.

</DOC>
<DOC>
<DOCNO> 8321 </DOCNO>
Quantum Algorithms and the Genetic Code


  Replication of DNA and synthesis of proteins are studied from the view-point
of quantum database search. Identification of a base-pairing with a quantum
query gives a natural (and first ever) explanation of why living organisms have
4 nucleotide bases and 20 amino acids. It is amazing that these numbers arise
as solutions to an optimisation problem. Components of the DNA structure which
implement Grover's algorithm are identified, and a physical scenario is
presented for the execution of the quantum algorithm. It is proposed that
enzymes play a crucial role in maintaining quantum coherence of the process.
Experimental tests that can verify this scenario are pointed out.

</DOC>
<DOC>
<DOCNO> 101711 </DOCNO>
Locality and modular invariance in 2D conformal QFT


  The relations and differences between various classification problems arising
in the context of local two-dimensional conformal QFT, modular invariants, and
subfactors are discussed. The extent to which locality implies modular
invariance, is exhibited.

</DOC>
<DOC>
<DOCNO> 100393 </DOCNO>
Braid Groups are Linear


  The braid groups B_n can be defined as the mapping class group of the
n-punctured disc. The Lawrence-Krammer representation of the braid group B_n is
the induced action on a certain twisted second homology of the space of
unordered pairs of points in the n-punctured disc. Recently, Daan Krammer
showed that this is a faithful representation in the case n=4. In this paper,
we show that it is faithful for all n.

</DOC>
<DOC>
<DOCNO> 70457 </DOCNO>
The implementation of the four-jet matrix elements in HERWIG and


  The new version 6.1 of the HERWIG event generator allows one to simulate
hadronic final states in electron-positron annihilations using the
$O(\alpha_s^2)$ partonic matrix elements (MEs) for $e^+e^-\to q\bar qgg$ and
$e^+e^-\to q\bar q Q\bar Q$. The consequent phenomenology is discussed in the
case of four-jet signatures of particular relevance to future electron-positron
Linear Colliders (LCs), such as in Higgs boson searches. The new approach
adopted in HERWIG is compared to the standard $O(\alpha_s)$ description, as
well as to other recently presented event generators also based on $e^+e^-\to4$
parton MEs.

</DOC>
<DOC>
<DOCNO> 118642 </DOCNO>
Intervening O VI Quasar Absorption Systems at Low Redshift: A


  FUV echelle spectroscopy of the radio-quiet QSO H1821+643 (z = 0.297),
obtained with the Space Telescope Imaging Spectrograph (STIS) at 7 km/s
resolution, reveals 4 definite O VI absorption line systems and one probable O
VI absorber at 0.15 < z(abs) < 0.27. The four definite O VI absorbers are
located near galaxies and are highly displaced from the quasar in redshift;
these are likely intervening systems unrelated to the background QSO. In the
case of the strong O VI system at z(abs) = 0.22497, multiple components are
detected in Si III and O VI as well as H I Lyman series lines, and the
differing component velocity centroids and b-values firmly establish that this
is a multiphase absorption system. A weak O VI absorber is detected at z(abs) =
0.22637, i.e., offset by ~340 km/s from the z(abs) = 0.22497 system. Lya
absorption is detected at z(abs) = 0.22613, but no Lya absorption is
significantly detected at 0.22637. Other weak O VI absorbers at z(abs) =
0.24531 and 0.26659 and the probable O VI system at 0.21326 have widely diverse
O VI/H I column density ratios with N(O VI)/N(H I) ranging from <=0.14+/-0.03
to 5.2+/-1.2. The number density of O VI absorbers with rest equivalent width >
30 mA in the H1821+643 spectrum is remarkably high, dN/dz ~48, with a high
(90%) confidence that it is greater than 17. We conservatively estimate that
the cosmological mass density of the O VI systems Omega_b(O VI) > 0.0008/h_75.
With an assumed metallicity of 1/10 solar and a conservative assumption that
the fraction of oxygen in the O VI ionization stage is 0.2, we obtain Omega_b(O
VI) > 0.004/h_75. This is comparable to the combined cosmological mass density
of stars and cool gas in galaxies and X-ray emitting gas in galaxy clusters at
low redshift.

</DOC>
<DOC>
<DOCNO> 7783 </DOCNO>
Unconventional strong pinning in the low temperature phase of


  We investigated low field vortex dynamics in a single crystal of
U_.9725Th_.0275Be_13. We found a sharp transition in the vortex creep rate at
the lower transition temperature T_c2, coincident with the second jump in the
specific heat. In the high-temperature phase, rather strong creep rates are
observed. In the low temperature phase, the rates drop to undetectabely low
levels. This behaviour indicates that a very strong pinning mechanism is
present in the low temperature phase of U_.9725Th_.0275Be_13, which could be
explained by the existence of domain walls, separating discreetly degenerate
states of a superconductor, that can sustain fractional vortices and thus act
as very strong pinning centers.

</DOC>
<DOC>
<DOCNO> 10484 </DOCNO>
Anomalous Coherent Backscattering of Light from Opal Photonic Crystals


  We studied coherent backscattering (CBS) of light from opal photonic crystals
in air at different incident inclination angles, wavelengths and along various
[hkl] directions inside the opals. Similar to previously obtained CBS cones
from various random media, we found that when Bragg condition with the incident
light beam is not met then the CBS cones from opals show a triangular line
shape in excellent agreement with light diffusion theory. At Bragg condition,
however, we observed a dramatic broadening of the opal CBS cones that depends
on the incident angle and [hkl] direction. This broadening is explained as due
to the light intensity decay in course of propagation along the Bragg direction
{\em before the first} and {\em after the last} scattering events. We modified
the CBS theory to incorporate the attenuation that results from the photonic
band structure of the medium. Using the modified theory we extract from our CBS
data the light mean free path and Bragg attenuation length at different [hkl].
Our study shows that CBS measurements are a unique experimental technique to
explore photonic crystals with disorder, when other spectroscopical methods
become ambiguous due to disorder-induced broadening.

</DOC>
<DOC>
<DOCNO> 120007 </DOCNO>
Optical Spectroscopy of Supernova 1993J During Its First 2500 Days


  We present 42 low-resolution spectra of Supernova (SN) 1993J, our complete
collection from the Lick and Keck Observatories, from day 3 after explosion to
day 2454, as well as one Keck high-dispersion spectrum from day 383. SN 1993J
began as an apparent SN II, albeit an unusual one. After a few weeks, a
dramatic transition took place, as prominent helium lines emerged in the
spectrum. SN 1993J had metamorphosed from a SN II to a SN IIb. Nebular spectra
of SN 1993J closely resemble those of SNe Ib and Ic, but with a persistent
H_alpha line. At very late times, the H_alpha emission line dominated the
spectrum, but with an unusual, box-like profile. This is interpreted as an
indication of circumstellar interaction.

</DOC>
<DOC>
<DOCNO> 10787 </DOCNO>
Electronic correlation effects and the Coulomb gap at finite temperature


  We have investigated the effect of the long-range Coulomb interaction on the
one-particle excitation spectrum of n-type Germanium, using tunneling
spectroscopy on mechanically controllable break junctions. The tunnel
conductance was measured as a function of energy and temperature. At low
temperatures, the spectra reveal a minimum at zero bias voltage due to the
Coulomb gap. In the temperature range above 1 K the Coulomb gap is filled by
thermal excitations. This behavior is reflected in the temperature dependence
of the variable-range hopping resitivity measured on the same samples: Up to a
few degrees Kelvin the Efros-Shkovskii ln$R \propto T^{-1/2}$ law is obeyed,
whereas at higher temperatures deviations from this law are observed,
indicating a cross-over to Mott's ln$R \propto T^{-1/4}$ law. The mechanism of
this cross-over is different from that considered previously in the literature.

</DOC>
<DOC>
<DOCNO> 116717 </DOCNO>
A new Loan-Stock Financial Instrument


  A new financial instrument (a new kind of a loan) is introduced. The
loan-stock instrument (LSI) combines fixed rate instruments (loans, etc.) with
other financial instruments that have higher volatilities and returns (stocks,
mutual funds, currencies, derivatives, options, etc.). This new loan depends on
the value of underlying security (for example, stock) in such a way that when
underlying security increases, the value of loan decreases and backwards. The
procedure to create a risk free portfolio and a technique to fairly price the
LSI is described. The philosophy behind this procedure is quite similar to the
Black-Scholes formalism in option theory. Creation of the risk free portfolio
is possible because the change in the underlying security offsets the change in
the value of the loan (or the amount that the borrower has to repay). The new
financial instrument takes an advantage of the fact that on average the stock
market grows in time. It is beneficial for both the borrower and the lender.
The LSI is more attractive for the borrower than the traditional loan is due to
the decrease in the amount that has to be repaid. This attractiveness
constitutes the benefit for the lender in terms of the market share among the
borrowers. In addition, the lender can charge the extra premium.

</DOC>
<DOC>
<DOCNO> 99676 </DOCNO>
Hamiltonian Gromov-Witten invariants


  In this paper we introduce invariants of semi-free Hamiltonian actions of
$S\sp 1$ on compact symplectic manifolds (which satisfy some technical
conditions related to positivity) using the space of solutions to certain gauge
theoretical equations. These equations generalize at the same time the vortex
equations and the holomorphicity equation used in Gromov-Witten theory. In the
definition of the invariants we combine ideas coming from gauge theory and the
ideas underlying the construction of Gromov-Witten invariants. This paper is
based on a part of my PhD Thesis (see math/9912150).

</DOC>
<DOC>
<DOCNO> 120098 </DOCNO>
Box- and peanut-shaped bulges: I. Statistics


  We present a classification for bulges of a complete sample of ~1350 edge-on
disk galaxies derived from the RC3 (Third Reference Catalogue of Bright
Galaxies, de Vaucouleurs et al. 1991). A visual classification of the bulges
using the Digitized Sky Survey (DSS) in three types of b/p bulges or as an
elliptical type is presented and supported by CCD images. NIR observations
reveal that dust extinction does almost not influence the shape of bulges.
There is no substantial difference between the shape of bulges in the optical
and in the NIR. Our analysis reveals that 45% of all bulges are box- and
peanut-shaped (b/p). The frequency of b/p bulges for all morphological types
from S0 to Sd is > 40%. In particular, this is for the first time that such a
large frequency of b/p bulges is reported for galaxies as late as Sd. The
fraction of the observed b/p bulges is large enough to explain the b/p bulges
by bars.

</DOC>
<DOC>
<DOCNO> 80942 </DOCNO>
Low Dirac Eigenmodes and the Topological and Chiral Structure of the QCD


  Several lattice calculations which probe the chiral and topological structure
of QCD are discussed. The results focus attention on the low-lying eigenmodes
of the Dirac operator in typical gauge field configurations.

</DOC>
<DOC>
<DOCNO> 151375 </DOCNO>
Supersymmetric Noether Currents and Seiberg-Witten Theory


  A reliable method to construct Supersymmetric Noether currents is presented.
As the most important application the central charge of the N=2 Supersymmetric
Yang-Mills effective theory, known as Seiberg-Witten (SW) theory, is computed.
The analisys is carried out in the SW low energy U(1) effective Sector, as well
as in the SW high energy SU(2) effective Sector.

</DOC>
<DOC>
<DOCNO> 12277 </DOCNO>
Direct observation of the washboard noise of a driven vortex lattice in


  We studied the conduction noise spectrum in the vortex state of a
high-temperature superconductor, Bi2Sr2CaCu2Oy, subject to a uniform driving
force. Two characteristic features, a broadband noise (BBN) and a narrow-band
noise (NBN), were observed in the vortex-solid phase. The origin of the large
BBN was determined to be plastic motion of the vortices, whereas the NBN was
found to originate from the washboard modulation of the translational velocity
of the driven vortices. We believe this to be the first observation of

</DOC>
<DOC>
<DOCNO> 68168 </DOCNO>
Photon mixing in universes with large extra-dimensions


  In presence of a magnetic field, photons can mix with any particle having a
two-photon vertex. In theories with large compact extra-dimensions, there
exists a hierachy of massive Kaluza-Klein gravitons that couple to any photon
entering a magnetic field. We study this mixing and show that, in comparison
with the four dimensional situation where the photon couples only to the
massless graviton, the oscillation effect may be enhanced due to the existence
of a large number of Kaluza-Klein modes. We give the conditions for such an
enhancement and then investigate the cosmological and astrophysical
consequences of this phenomenon; we also discuss some laboratory experiments.
Axions also couple to photons in the same way; we discuss the effect of the
existence of bulk axions in universes with large extra-dimensions. The results
can also be applied to neutrino physics with extra-dimensions.

</DOC>
<DOC>
<DOCNO> 121917 </DOCNO>
Dynamics of Cuspy Triaxial Galaxies with a Supermassive Black Hole


  This talk provides a progress report on an extended collaboration which has
aimed to address two basic questions, namely: Should one expect to see cuspy,
triaxial galaxies in nature? And can one construct realistic cuspy, triaxial
equilibrium models that are robust? Three technical results are described: (1)
Unperturbed chaotic orbits in cuspy triaxial potentials can be extraordinarily
sticky, much more so than orbits in many other three-dimensional potentials.
(2) Even very weak perturbations can be important by drastically reducing,
albeit not completely eliminating, this stickiness. (3) A simple toy model
facilitates a simple understanding of why black holes and cusps can serve as an
effective source of chaos. These results suggest that, when constructing models
of galaxies using Schwarzschild's method or any analogue thereof, astronomers
would be well advised to use orbital building blocks that have been perturbed
by `noise' or other weak irregularities, since such building blocks are likely
to be more nearly time-independent than orbits evolved in the absence of all
perturbations.

</DOC>
<DOC>
<DOCNO> 121662 </DOCNO>
Probing the Inner Region of Cyg X-1 in the Low/Hard State through its


  We present the broad band X-ray spectrum of Cyg X-1 in the low/hard state as
observed by the instruments on board of BeppoSAX. The spectrum spans from 0.1
to 200 keV, allowing the total accretion luminosity to be observed, rather than
extrapolated, corresponding to ~2 per cent of the Eddington limit for a 10
Solar mass black hole. The broad bandpass allows us to determine the continuum
shape with great accuracy. Simple models of Compton up-scattering of seed
photons from the accretion disk do not adequately match the spectrum. At low
energies an additional continuum component is required, giving a complex soft
excess which extends up to ~4 keV, in line with previous results from ASCA.
Moreover we clearly detect a reflected component from the accretion disk which
is smeared, probably because of relativistic and Doppler effects. The
reflecting material is not strongly ionized and does not subtend a large solid
angle as seen from the corona. The inner radius of the disk, that depends on
the inclination of the system, is most probably between 10 and 70 gravitational
radii (Rg). An unsmeared reprocessed component, probably originating from the
companion star or the outer disk, could also be present. In this case, the
inner radius of the disk, as inferred from the smeared reflection, is smaller,
between 6 and 20 Rg.

</DOC>
<DOC>
<DOCNO> 68371 </DOCNO>
Lattice calculation of $1/p^2$ corrections to $\alpha_s$ and of


  We report on very strong evidence of the occurrence of power terms in
$\as(p)$, the QCD running coupling constant in the $\widetilde{MOM}$ scheme, by
analyzing non-perturbative measurements from the lattice three-gluon vertex
between 2.0 and 10.0 GeV at zero flavor. While putting forward the caveat that
this definition of the coupling is a gauge dependent one, the general relevance
of such an occurrence is discussed. We fit $\Lambda_{\bar{\rm MS}}^{(n_f=0)}=
237 \pm 3 ^{+ 0}_{-10}$ MeV in perfect agreement with the result obtained by
the ALPHA group with a totally different method.
  The power correction to $\as(p)$ is fitted to $(0.63\pm 0.03 ^{+ 0.0}_{-
0.13}) {\rm GeV}^2/p^2$.

</DOC>
<DOC>
<DOCNO> 118368 </DOCNO>
Primordial Nucleosynthesis For The New Millennium


  The physics of the standard hot big bang cosmology ensures that the early
Universe was a primordial nuclear reactor, synthesizing the light nuclides (D,
3He, 4He, and 7Li) in the first 20 minutes of its evolution. After an overview
of nucleosynthesis in the standard model (SBBN), the primordial abundance
yields will be presented, followed by a status report (intended to stimulate
further discussion during this symposium) on the progress along the road from
observational data to inferred primordial abundances. Theory will be confronted
with observations to assess the consistency of SBBN and to constrain cosmology
and particle physics. Some of the issues/problems key to SBBN in the new
millenium will be highlighted, along with a wish list to challenge theorists
and observers alike.

</DOC>
<DOC>
<DOCNO> 11964 </DOCNO>
Entropic Elasticity of Phantom Percolation Networks


  A new method is used to measure the stress and elastic constants of purely
entropic phantom networks, in which a fraction $p$ of neighbors are tethered by
inextensible bonds. We find that close to the percolation threshold $p_c$ the
shear modulus behaves as $(p-p_c)^f$, where the exponent $f\approx 1.35$ in two
dimensions, and $f\approx 1.95$ in three dimensions, close to the corresponding
values of the conductivity exponent in random resistor networks. The components
of the stiffness tensor (elastic constants) of the spanning cluster follow a
power law $\sim(p-p_c)^g$, with an exponent $g\approx 2.0$ and 2.6 in two and
three dimensions, respectively.

</DOC>
<DOC>
<DOCNO> 10531 </DOCNO>
Spin-triplet `f-wave' pairing proposed for an organic superconductor


  By examining how the spin- and/or charge-fluctuation exchange can contribute
to pairing instabilities, we propose that a spin-triplet f-wave-like pairing
with a d-vector perpendicular to the b-axis may be realized in (TMTSF)_2 PF_6
due to (i) a quasi-one-dimensional Fermi surface, (ii) a coexistence of 2k_F
charge fluctuations and spin fluctuations, and (iii) an anisotropy in spin
fluctuations. Fluctuation-exchange study for the Hubbard model confirms the
point (i), while a phenomelogical analysis is given for (ii) and (iii). The
proposed pairing is consistent with various experiments.

</DOC>
<DOC>
<DOCNO> 71445 </DOCNO>
Effective Interactions are Effective Interactions


  The subject of effective interactions is introduced and applications in both
quantum mechanics and quantum field theory are presented. In particular the use
of chiral perturbation theory as an effective low energy description of QCD is
developed and it is argued that such methods rally are effective in both the
meson and baryonic sectors.

</DOC>
<DOC>
<DOCNO> 170655 </DOCNO>
Quantum Strategy Without Entanglement


  In this paper we quantize the Card Game. In the classical version of this
game, one player (Alice) can always win with propability 2/3. But when the
other player (Bob) is allowed to apply quantum strategy, the original unfair
game turns into a fair and zero-sum game. Further more, the procedure in which
Bob perform his quantum strategy does not include any ingredient of
entanglement.

</DOC>
<DOC>
<DOCNO> 150721 </DOCNO>
On Seven-Brane and Instanton Solutions of Type IIB


  It is shown that magnetic seven-branes previously considered as different
objects are members of a one-parametric family of supersymmetric seven branes.
We enlarge the class of seven-branes by constructing new magnetically and also
electrically charged seven branes. The solutions display a kink-like behavior.
We also construct a solution that naturally generalizes the D-instanton.

</DOC>
<DOC>
<DOCNO> 68171 </DOCNO>
Soft-Gluon Resummation and PDF Theory Uncertainties


  Parton distribution functions are determined by the comparison of
finite-order calculations with data. We briefly discuss the interplay of higher
order corrections and PDF determinations, and the use of soft-gluon resummation
in global fits.

</DOC>
<DOC>
<DOCNO> 170333 </DOCNO>
Security of EPR-based Quantum Key Distribution using three bases


  Modifications to a previous proof of the security of EPR-based quantum key
distribution are proposed. This modified version applies to a protocol using
three conjugate measurement bases rather than two. A higher tolerable error
rate is obtained for the three-basis protocol.

</DOC>
<DOC>
<DOCNO> 12757 </DOCNO>
Pairing Mechanism in the doped Hubbard Antiferromagnet: the $4 \times 4$


  We introduce a {\em local} formalism, in terms of eigenstates of number
operators, having well defined point symmetry, to solve the Hubbard model at
weak coupling on a $N\times N$ square lattice (for even $N$). The key concept
is that of W=0 states, that are the many-body eigenstates of the kinetic energy
with vanishing Hubbard repulsion. At half filling, the wave function
demonstrates an antiferromagnetic order, a lattice step translation being
equivalent to a spin flip. Further, we state a general theorem which allows to
find all the W=0 pairs (two-body W=0 singlet states). We show that, in special
cases, this assigns the ground state symmetries at least in the weak coupling
regime. The N=4 case is discussed in detail. To study the doped half filled
system, we enhance the Group Theory analysis of the $4 \times 4$ Hubbard model
introducing an Optimal Group which explains all the degeneracies in the
one-body and many-body spectra. We use the Optimal Group to predict the
possible ground state symmetries of the $4 \times 4$ doped antiferromagnet by
means of our general theorem and the results are in agreement with exact
diagonalization data. Then we create W=0 {\it electron} pairs over the
antiferromagnetic state. We show analitycally that the effective interaction
between the electrons of the pairs is attractive and forms bound states.
Computing the corresponding binding energy we are able to definitively predict
the exact ground state symmetry.

</DOC>
<DOC>
<DOCNO> 69352 </DOCNO>
Hadronic Properties from Lattice QCD with Dynamical Quarks


  The lattice regularization of QCD provides us with the most systematic way of
computing non-perturbative properties of hadrons directly from the first
principles of QCD. The recent rapid development of parallel computers has
enabled us to start realistic and systematic simulations with dynamical quarks.
In this paper, I report on the first results from recent systematic studies on
the lattice with dynamical quarks.

</DOC>
<DOC>
<DOCNO> 121323 </DOCNO>
FIRES at the VLT: Measuring the Rest-Frame V-Band Luminosity of Galaxies


  We present early results from the Faint InfraRed Extragalactic Survey (FIRES)
at the VLT, the main goal of which is to study galaxy evolution in a deep,
K-band selected sample. With our NIR selection, we select galaxies based on
their rest-frame optical light at all redshifts z<3. Our seven band photometry,
coupled with an accurate and reliable photometric redshift technique, gives us
the ability to study galaxies at the same rest-frame wavelength across a large
range in redshift. We present here the rest-frame V-band luminosity of objects
in our sample as a function of redshift and demonstrate the importance of near
infrared data in measuring the correct photometric redshift and rest-frame
optical luminosity.

</DOC>
<DOC>
<DOCNO> 152406 </DOCNO>
Glueball Masses for the Deformed Conifold Theory


  We obtain the spectrum of glueball masses for the N=1 non-conformal cascade
theory whose supergravity dual was recently constructed by Klebanov and
Strassler. The glueball masses are calculated by solving the supergravity
equations of motion for the dilaton and the two-form in the deformed conifold
background.

</DOC>
<DOC>
<DOCNO> 9371 </DOCNO>
Shallow Coulomb Gap and Weak Level-Level Correlations in a Deeply


  We consider a system of two-dimensional electrons strongly localized by
disorder. Interactions create a gap in the average tunneling density of states
$\nu(E)$ at energies, E, close to the Fermi level. We derive a system of
self-consistent equations for the correlators of local densities of occupied
and empty states. When either the interactions are screened by the gate or the
temperature, T, is high enough, so that the Coulomb gap is shallow, the
perturbative solution of the system yields analytical expressions for the
interaction-induced correction $\delta\nu(E)$ and the level-level correlator.
We show that even with short-range interactions, $\delta\nu (E)$ exhibits a
singular energy dependence at T=0. We also demonstrate that at high T this
energy dependence is a universal function of the the ratio $E/T$. Regarding the
level correlations, we trace how the correlator falls off as a function of
spatial and energy separation between the levels. We also trace how the
correlations vanish with increasing T. Our most noticeable observation is that
for two close energies the correlator changes sign from positive (attraction)
at small distances to negative (repulsion) at large distances.

</DOC>
<DOC>
<DOCNO> 7822 </DOCNO>
Vortices in small superconducting disks


  We study the Ginzburg-Landau equations in order to describe a two-dimensional
superconductor in a bounded domain. Using the properties of a particular
integrability point ($\kappa = 1/ \sqrt2$) of these nonlinear equations which
allows vortex solutions, we obtain a closed expression for the energy of the
superconductor. The presence of the boundary provides a selection mechanism for
the number of vortices.
  A perturbation analysis around $\kappa = 1/ \sqrt2$ enables us to include the
effects of the vortex interactions and to describe quantitatively the
magnetization curves recently measured on small superconducting disks.
  We also calculate the optimal vortex configuration and obtain an expression
for the confining potential away from the London limit.

</DOC>
<DOC>
<DOCNO> 71814 </DOCNO>
SUSY at the Linear Colliders: Working Group Summary


  I summarise the activities of the different members of the SUSY working
group. There have been two major areas of activity: 1) precision measurement of
the SUSY particle masses/couplings and hence those of the SUSY model
parameters, 2) investigations into SUSY searches at \eplem, \gamgam, $\game$
and $\emem$ colliders, in the nonstandard scenarios such as explicit CP
violation, R-parity violation and Anomaly Mediated Supersymmtery Breaking. In
addition there have been studies which looked at the effect of `large' extra
dimensions at the various colliders mentioned above.

</DOC>
<DOC>
<DOCNO> 68281 </DOCNO>
Seesaw mechanism, quark-lepton symmetry and Majorana phases


  A previous short analysis of the seesaw mechanism, based on quark-lepton
symmetry, experimental data and hierarchical neutrino spectrum, is enlarged to
include small but not zero U_{e3}, inverted mass hierarchy, and the qualitative
effect of Majorana phases. The structure of the heavy neutrino mass matrix
obtained in several cases is discussed. We find two leading forms for this
matrix. One is diagonal and stands at the unification scale or above. The other
is off-diagonal and stands at the intermediate scale.

</DOC>
<DOC>
<DOCNO> 151490 </DOCNO>
Gepner-like Description of a String Theory on a Noncompact Singular


  We investigate a Gepner-like superstring model described by a combination of
multiple minimal models and an N=2 Liouville theory. This model is thought to
be equivalent to the superstring theory on a singular noncompact Calabi-Yau
manifold. We construct the modular invariant partition function of this model,
and confirm the validity of an appropriate GSO projection. We also calculate
the elliptic genus and Witten index of the model. We find that the elliptic
genus factorises into a rather trivial factor and a non-trivial one, and the
non-trivial one has the information on the positively curved base manifold of
the cone.

</DOC>
<DOC>
<DOCNO> 81001 </DOCNO>
QCD3 and the Replica Method


  Using the replica method, we analyze the mass dependence of the QCD3
partition function in a parameter range where the leading contribution is from
the zero momentum Goldstone fields. Three complementary approaches are
considered in this article. First, we derive exact relations between the QCD3
partition function and the QCD4 partition function continued to half-integer
topological charge. The replica limit of these formulas results in exact
relations between the corresponding microscopic spectral densities of QCD3 and
QCD4. Replica calculations, which are exact for QCD4 at half-integer
topological charge, thus result in exact expressions for the microscopic
spectral density of the QCD3 Dirac operator. Second, we derive Virasoro
constraints for the QCD3 partition function. They uniquely determine the
small-mass expansion of the partition function and the corresponding sum rules
for inverse Dirac eigenvalues. Due to de Wit-'t Hooft poles, the replica limit
only reproduces the small mass expansion of the resolvent up to a finite number
of terms. Third, the large mass expansion of the resolvent is obtained from the
replica limit of a loop expansion of the QCD3 partition function. Because of
Duistermaat-Heckman localization exact results are obtained for the microscopic
spectral density in this way.

</DOC>
<DOC>
<DOCNO> 85016 </DOCNO>
Hierarchies of invariant spin models


  In this paper we present classes of state sum models based on the recoupling
theory of angular momenta of SU(2) (and of its q-counterpart $U_q(sl(2))$, q a
root of unity). Such classes are arranged in hierarchies depending on the
dimension d, and include all known closed models, i.e. the Ponzano-Regge state
sum and the Turaev-Viro invariant in dimension d=3, the Crane-Yetter invariant
in d=4. In general, the recoupling coefficient associated with a d-simplex
turns out to be a $\{3(d-2)(d+1)/2\}j$ symbol, or its q-analog. Each of the
state sums can be further extended to compact triangulations $(T^d,\partial
T^d)$ of a PL-pair $(M^d,\partial M^d)$, where the triangulation of the
boundary manifold is not keeped fixed. In both cases we find out the algebraic
identities which translate complete sets of topological moves, thus showing
that all state sums are actually independent of the particular triangulation
chosen. Then, owing to Pachner's theorems, it turns out that classes of
PL-invariant models can be defined in any dimension d.

</DOC>
<DOC>
<DOCNO> 11559 </DOCNO>
Noncommutative Torus from Fibonacci Chains via Foliation


  We classify the Fibonacci chains (F-chains) by their index sequences and
construct an approximately finite dimensional (AF) $C^*$-algebra on the space
of F-chains as Connes did on the space of Penrose tiling. The K-theory on this
AF-algebra suggests a connection between the noncommutative torus and the space
of F-chains. A noncommutative torus, which can be regarded as the $C^*$-algebra
of a foliation on the torus, is explicitly embedded into the AF-algebra on the
space of F-chains. As a counterpart of that, we obtain a relation between the
space of F-chains and the leaf space of Kronecker foliation on the torus using
the cut-procedure of constructing F-chains.

</DOC>
<DOC>
<DOCNO> 7851 </DOCNO>
On the problem of neural network decomposition into some subnets


  An artificial neural network is usually treated as a whole system, being
characterized by its ground state (the global minimum of the energy
functional), the set of fixed points, their basins of attraction, etc. However,
it is quite natural to suppose that a large network may consist of a set of
almost autonome subnets. Each subnet works independently (or almost
independently) and analyzes the same pattern from other points of view. It
seems that it is a proper model for the natural neural networks. We discuss the
problem of decomposition of a neural network into a set of weakly coupled
subnets. The used technique is similar to the method for {\it the extremal
grouping of parameters}, proposed by E.M.Braverman (1970).

</DOC>
<DOC>
<DOCNO> 122273 </DOCNO>
Constraints on the Birth Aggregate of the Solar System


  Using the observed properties of our solar system, in particular the isotopic
compositions of meteorites and the regularity of the planetary orbits, we
constrain the star formation environment of the Sun within the scenario of
(external) radioactive enrichment by a massive star. This calculation yields a
probability distribution for the number of stars in the solar birth aggregate.
The Sun is most likely to have formed within a stellar group containing $N$ =
2000 $\pm$ 1100 members. The {\it a priori} probability of a star forming in
this type of environment is ${\cal P} \approx$ 0.0085, i.e., only about 1 out
of 120 solar systems are expected to form under similar conditions. We discuss
additional implications of this scenario, including possible effects from the
radiation fields provided by the putative cluster environment and dynamical
disruption of the Kuiper Belt. The constraints of this paper place tight
restrictions on the properties of the solar birth aggregate for the scenario of
external enrichment by a massive star; alternately, these tight constraints
slightly favor a self-enrichment scenario for the short-lived radioactive
species.

</DOC>
<DOC>
<DOCNO> 85144 </DOCNO>
Process Physics: Modelling Reality as Self-Organising Information


  The new Process Physics models reality as self-organising relational
information and takes account of the limitations of logic, discovered by Godel
and extended by Chaitin, by using the concept of self-referential noise. Space
and quantum physics are emergent and unified, and described by a Quantum
Homotopic Field Theory of fractal topological defects embedded in a three
dimensional fractal process-space.

</DOC>
<DOC>
<DOCNO> 39641 </DOCNO>
a_1\pi Contribution to e^+e^-\to 4\pi Annihilation and \tau\to


  The results of the study of the process e^+e^- \to 4\pi by the CMD-2
collaboration at VEPP-2M are presented. Analysis of the differential
distributions demonstrates the dominance of the a_1\pi and \omega\pi
intermediate states. Simple model, based on the assumption of a_1(1260)\pi and
\omega\pi dominance as intermediate states, successfully describes also the
data of CLEOII and ALEPH obtained recently for the decay \tau\to
4\pi\nu_{\tau}.

</DOC>
<DOC>
<DOCNO> 101032 </DOCNO>
A simple proof of Bailey's very-well-poised 6-psi-6 summation


  We give elementary derivations of some classical summation formulae for
bilateral (basic) hypergeometric series. In particular, we apply Gauss' 2-F-1
summation and elementary series manipulations to give a simple proof of
Dougall's 2-H-2 summation. Similarly, we apply Rogers' nonterminating 6-phi-5
summation and elementary series manipulations to give a simple proof of
Bailey's very-well-poised 6-psi-6 summation. Our method of proof extends M.
Jackson's first elementary proof of Ramanujan's 1-psi-1 summation.

</DOC>
<DOC>
<DOCNO> 121368 </DOCNO>
Galaxies: The Long Wavelength View


  Far-infrared spectroscopy obtained with the ISO LWS has shown that there is
strong variation (more than 2 orders of magnitude) in the [C II]/FIR ratios in
galaxies extending from blue compact dwarfs, to normal and starburst galaxies,
down to elliptical and ultraluminous galaxies (ULIGs). The variation in the
relative [C II] 158 micron line strength has been attributed to low metallicity
in blue compact dwarfs, high <G_o>/n for normal galaxies and ULIGs, soft
radiation fields in ellipticals, and extinction or enhanced abundance of dust
in ionized regions in ULIGs.
  Full ISO/LWS far-infrared (43 - 197 micron) spectra of six nearby IR-bright
galaxies reveal a dramatic progression of decreasing fine-structure line
emission from ionized species to molecular (OH and H2O) absorption line
dominated. The archetypical ULIG, Arp 220, lies at the absorption line
dominated end of this sequence. For Arp 220, radiative transfer models indicate
that it is optically thick in the FIR and that the water molecules observed in
absorption are radiatively excited. If extinction plays a role in the sequence
it appears from this analysis that the affected regions are heavily obscured
even in the far-infrared, while the detected line emission is not more obscured
in ULIGs than in starbursts. Linear correlation between polycyclic aromatic
hydrocarbon (PAH) 6.2 micron feature strength and the [C II] 158 micron line
strength in starbursts and ULIGs suggests a similar effect for these emitting
species, and that the detected PAH emission is not more obscured in ULIGs than
in lower luminosity starbursts.

</DOC>
<DOC>
<DOCNO> 71214 </DOCNO>
A New Decomposition of pion-pion S-wave Interaction


  The experimental isoscalar $\pi\pi\to\pi\pi$ S-wave amplitude squared below
1.75 GeV is characterized by a very broad structure $f_0(400-1200)$ with two
narrow dips due to its destructive interference with the $f_0(980)$ and
$f_0(1500)$. The $f_0(1370)$ and $f_0(1710)$ do not show up clearly in the
$\pi\pi\to\pi\pi$ S-wave amplitude due to their weak coupling to $\pi\pi$. This
paper is about the controversial nature of the broad $f_0(400-1200)$. We
decompose it into two parts, i.e., t-channel $\rho$ meson exchange plus an
additional s-channel resonance $f_0(X)$. With the t-channel $\rho$ meson
exchange fixed by the isotensor $\pi\pi\to\pi\pi$ S-wave scattering, we re-fit
the CERN-Munich (CM) data on $\pi\pi$ scattering to get parameters for the
$f_0(X)$. We find that the $f_0(X)$ is very broad with a nearby pole at
(1.67-0.26i) GeV, while the t-channel $\rho$ meson exchange part produces a
pole at (0.36-0.53i) GeV. The implication of our results for the study of
$\sigma$ and glueball is discussed.

</DOC>
<DOC>
<DOCNO> 122288 </DOCNO>
X-ray Energy Spectra of the Super-soft X-ray Sources CAL87 and


  We report observation results of the super-soft X-ray sources (SSS) CAL87 and
RXJ0925.7-4758 with the X-ray CCD cameras (Solid-state Imaging Spectrometer;
SIS) on-board the ASCA satellite. We have applied theoretical spectral models
to CAL87, and constrained the white dwarf mass and intrinsic luminosity as 0.8
- 1.2 M_solar and 4 x 10^{37}- 1.2 x 10^{38} erg s^{-1}, respectively. However,
we have found the observed luminosity is an order of magnitude smaller than the
theoretical estimate, which indicates the white dwarf is permanently blocked by
the accretion disk, and we are observing a scattering emission by a fully
ionized accretion disk corona (ADC) whose column density is ~ 1.5 x 10^{23}
cm^{-2}. Through simulation, we have shown that the orbital eclipse can be
explained by the ADC model, such that a part of the extended X-ray emission
from the ADC is blocked by the companion star filling its Roche lobe. We have
found that very high surface gravity and temperature, ~ 10^{10} cm s^{-2} and ~
100 eV respectively, as well as a strong absorption edge at ~ 1.02 keV, are
required to explain the X-ray energy spectrum of RXJ0925.7-4758. These values
are only possible for an extremely heavy white dwarf near the Chandrasekhar
limit. Although the super soft source luminosity should be ~ 10^{38} erg s^{-1}
at the Chandrasekhar limit, the observed luminosity of RXJ0925.7-4758 is nearly
two orders of magnitude smaller even assuming an extreme distance of ~10 kpc.
To explain the luminosity discrepancy, we propose a model that very thick
matter which was previously ejected from the system, as a form of jets,
intervenes the line of sight, and reduces the luminosity significantly due to
Thomson scattering.

</DOC>
<DOC>
<DOCNO> 101730 </DOCNO>
Groups isomorphic to all their non-trivial normal subgroups


  In answer to a question of P. Hall, we supply another construction of a group
which is isomorphic to each of its non-trivial normal subgroups.

</DOC>
<DOC>
<DOCNO> 40014 </DOCNO>
Does LEP prefer the NMSSM?


  We study the naturalness of electroweak symmetry breaking and baryogenesis in
the next-to-minimal supersymmetric standard model (NMSSM). Our study is
motivated by the recent LEP bounds on the Higgs boson mass which severely
constrains the low \tan\beta region of the minimal supersymmetric standard
model (MSSM). We show that the low \tan \beta region of the NMSSM is clearly
favoured over the MSSM with regard to the physical Higgs boson mass,
fine-tuning, and electroweak baryogenesis.

</DOC>
<DOC>
<DOCNO> 10140 </DOCNO>
Time evolution of the Partridge-Barton Model


  The time evolution of the Partridge-Barton model in the presence of the
pleiotropic constraint and deleterious somatic mutations is exactly solved for
arbitrary fecundity in the context of a matricial formalism. Analytical
expressions for the time dependence of the mean survival probabilities are
derived. Using the fact that the asymptotic behavior for large time $t$ is
controlled by the largest matrix eigenvalue, we obtain the steady state values
for the mean survival probabilities and the Malthusian growth exponent. The
mean age of the population exhibits a $t^{-1}$ power law decayment. Some Monte
Carlo simulations were also performed and they corroborated our theoretical
results.

</DOC>
<DOC>
<DOCNO> 178836 </DOCNO>
Equivalence of model space techniques and the renormalization group for


  Lee-Suzuki similarity transformations and Krencigowa-Kuo folded diagrams are
two common methods used to derive energy independent model space effective
interactions for nuclear many-body systems. We demonstrate that these methods
are equivalent to a Renormalization Group (RG) analysis of a separable
potential model. The effective low-momentum potentials V_{eff} are shown to
give the same scaling equation that RG arguments predict. We find the new
result that the different model space techniques considered in this paper yield
a unique low-momentum V_{eff} when applied to the toy model problem.

</DOC>
<DOC>
<DOCNO> 121594 </DOCNO>
High Speed Interconnects and Parallel Software Libraries: Enabling


  The NVOs core data mining and archive federation activities are heavily
dependent on the underlying data pipeline software necessary to translate the
raw data into scientifically relevant source detections. The data pipeline
software dictates: the raw data storage and retrieval mechanisms, the meaning
and format of the fields in the source catalogs, and the ability of the NVO
users to re-analyze raw data for their own purposes. Increasing the performance
of the core data pipeline software so that it can address the needs of current
and future high data rate surveys is an important activity that should be
addressed in concert with the development of the NVO.

</DOC>
<DOC>
<DOCNO> 67757 </DOCNO>
On conditions for the nonperturbative equivalence of ultraviolet cut-off


  We consider procedures through which an ultraviolet cut-off regularization
scheme can be modified to reproduce the same results for nonperturbative
renormalized Green's functions as obtained from a dimensional regularization
scheme. These issues are considered within the Dyson-Schwinger equation
framework, where ultraviolet cut-off regularization can lead to explicit
violations of gauge invariance. As a specific illustration, we consider the
electron self-energy in quenched QED_4 in both schemes and establish those
procedures for which the UV cut-off scheme can be expected to lead to the
dimensional regularization results. We also compare results from precise
numerical studies using the two types of regularization.

</DOC>
<DOC>
<DOCNO> 84509 </DOCNO>
Fibre bundle formulation of nonrelativistic quantum mechanics (full


  We propose a new systematic fibre bundle formulation of nonrelativistic
quantum mechanics. The new form of the theory is equivalent to the usual one
and is in harmony with the modern trends in theoretical physics and potentially
admits new generalizations in different directions. In it the Hilbert space of
a quantum system (from conventional quantum mechanics) is replaced with an
appropriate Hilbert bundle of states and a pure state of the system is
described by a lifting of paths or section along paths in this bundle. The
evolution of a pure state is determined through the bundle (analogue of the)
Schr\"odinger equation. Now the dynamical variables and the density operator
are described via liftings of paths or morphisms along paths in suitable
bundles. The mentioned quantities are connected by a number of relations
derived in this work.

</DOC>
<DOC>
<DOCNO> 169681 </DOCNO>
Activating bound entanglement in multi-particle systems


  We analyze the existence of activable bound entangled states in
multi-particle systems. We first give a series of examples which illustrate
some different ways in which bound entangled states can be activated by letting
some of the parties to share maximally entangled states. Then, we derive
necessary conditions for a state to be distillable as well as to be activable.
These conditions turn out to be also sufficient for a certain family of
multi-qubit states. We use these results to explicitely to construct states
displaying novel properties related to bound entanglement and its activation.

</DOC>
<DOC>
<DOCNO> 84930 </DOCNO>
Method of complex paths and general covariance of Hawking radiation


  We apply the technique of complex paths to obtain Hawking radiation in
different coordinate representations of the Schwarzschild space-time. The
coordinate representations we consider do not possess a singularity at the
horizon unlike the standard Schwarzschild coordinate. However, the event
horizon manifests itself as a singularity in the expression for the
semi-classical action. This singularity is regularized by using the method of
complex paths and we find that Hawking radiation is recovered in these
coordinates indicating the covariance of Hawking radiation. This also shows
that there is no correspondence between the particles detected by the model
detector and the particle spectrum obtained by the quantum field theoretic
analysis -- a result known in other contexts as well.

</DOC>
<DOC>
<DOCNO> 13169 </DOCNO>
Metallic single-electron transistor without traditional tunnel barriers


  We report on a new type of single-electron transistor (SET) comprising two
highly resistive Cr thin-film strips (~ 1um long) connecting a 1 um-long Al
island to two Al outer electrodes. These resistors replace small-area oxide
tunnel junctions of traditional SETs. Our transistor with a total asymptotic
resistance of 110 kOhm showed a very sharp Coulomb blockade and reproducible,
deep and strictly e-periodic gate modulation in wide ranges of bias currents I
and gate voltages V_g. In the Coulomb blockade region (|V| < 0.5 mV), we
observed a strong suppression of the cotunneling current allowing appreciable
modulation curves V-V_g to be measured at currents I as low as 100 fA. The
noise figure of our SET was found to be similar to that of typical Al/AlOx/Al
single-electron transistors.

</DOC>
<DOC>
<DOCNO> 151115 </DOCNO>
Open-Closed String Field Theory in the Background B-Field


  In this paper, we study open-closed string field theory in the background
B-field in the so-called alpha=p^{+} formulation. The string field theory in
the infrared gives noncommutative gauge theory in the open string sector. Since
this theory includes closed string fields as dynamical variables, we can obtain
another string field theory in the same background through the condensation of
closed string fields, whose low-energy effective action does not show the
noncommutativity of spacetime. Although we have two string field theories in
the same background, we show that these theories are equivalent. In fact, we
give the unitary transformation from string fields in one of them to string
fields in the other.

</DOC>
<DOC>
<DOCNO> 12840 </DOCNO>
1D Potts, Yang-Lee Edges and Chaos


  It is known that the (exact) renormalization transformations for the
one-dimensional Ising model in field can be cast in the form of a logistic map
f(x) = 4 x (1 - x) with x a function of the Ising couplings. Remarkably, the
line bounding the region of chaotic behaviour in x is precisely that defining
the Yang-Lee edge singularity in the Ising model.
  In this paper we show that the one dimensional q-state Potts model for q
greater than or equal to 1 also displays such behaviour. A suitable combination
of Potts couplings can again be used to define an x satisfying f(x) = 4 x (1
-x). The Yang-Lee zeroes no longer lie on the unit circle in the complex z =
exp (h) plane, but their locus is still reproduced by the boundary of the
chaotic region in the logistic map.

</DOC>
<DOC>
<DOCNO> 101156 </DOCNO>
Lie Algebroids, Holonomy and Characteristic Classes


  We extend the notion of connection in order to be able to study singular
geometric structures, namely, we consider a notion of connection on a Lie
algebroid which is a natural extension of the usual concept of connection.
Using connections, we are able to define holonomy of the orbit foliation of a
Lie algebroid and prove a stability theorem. We also introduce secondary or
exotic characteristic classes that generalize the modular class of a Lie
algebroid.

</DOC>
<DOC>
<DOCNO> 120860 </DOCNO>
Isolated Neutron Stars in the Galaxy


  In this article we briefly review our recent results on evolution and
properties of isolated neutron stars (INSs) in the Galaxy.
  As the first step we calculate a {\it census} of INSs in our Galaxy.
  We infer a lower bound for the mean kick velocity of NSs, $ <V> \sim
$(200-300) ${\rm km s^{-1}}$. The same conclusion is reached for both a
constant magnetic field ($B\sim 10^{12}$ G) and for a magnetic field decaying
exponentially with a timescale $\sim 10^9$ yr. These results, moreover,
constrain the fraction of low velocity stars, which could have escaped pulsar
statistics, to $\sim$few percents.
  Then we show that the range of minimum value of magnetic moment, $\mu_b$:
$\sim 10^{29.5}\ge \mu_b \ge 10^{28} {\rm G} {\rm cm}^3$, and the
characteristic decay time, $t_d$: $\sim 10^8\ge t_d \ge 10^7 {\rm yrs}$, can be
excluded assuming the standard initial magnetic momentum, $\mu_0=10^{30} {\rm
G} {\rm cm}^3$, if accreting INSs are observed. For these parameters an INS
would never reach the stage of accretion from the interstellar medium even for
a low space velocity of the star and high density of the ambient plasma. The
range of excluded parameters increases for lower values of $\mu_0$.
  It is shown that old accreting INSs become more abundant than young cooling
INSs at X-ray fluxes below $\sim 10^{-13}$ erg cm$^{-2}$ s$^{-1}$. We can
predict that about one accreting INS per square degree should be observed at
the {\it Chandra} and {\it Newton} flux limits of $\sim 10^{-16}$ erg cm$^{-2}$
s$^{-1}.$ The weak {\it ROSAT} sources, associated with INSs, can be young
cooling objects, if the NSs birth rate in the solar vicinity during the last
$\sim 10^6$ yr was much higher than inferred from radiopulsar observations.

</DOC>
<DOC>
<DOCNO> 9940 </DOCNO>
Cellular solid behaviour of liquid crystal colloids. 1. Phase separation


  We study the phase ordering colloids suspended in a thermotropic nematic
liquid crystal below the clearing point Tni and the resulting aggregated
structure. Small (150nm) PMMA particles are dispersed in a classical liquid
crystal matrix, 5CB or MBBA. With the help of confocal microscopy we show that
small colloid particles densely aggregate on thin interfaces surrounding large
volumes of clean nematic liquid, thus forming an open cellular structure, with
the characteristic size of 10-100 micron inversely proportional to the colloid
concentration. A simple theoretical model, based on the Landau mean-field
treatment, is developed to describe the continuous phase separation and the
mechanism of cellular structure formation.

</DOC>
<DOC>
<DOCNO> 120654 </DOCNO>
CLASS B0827+525: `Dark lens' or binary radio-loud quasar?


  We present radio, optical, near-infrared and spectroscopic observations of
the source B0827+525. We consider this source as the best candidate from the
Cosmic Lens All-Sky Survey (CLASS) for a `dark lens' system or binary
radio-loud quasar. The system consists of two radio components with somewhat
different spectral indices, separated by 2.815 arcsec. VLBA observations show
that each component has substructure on a scale of a few mas. A deep K-band
exposure with the W.M.Keck-II Telescope reveals emission near both radio
components. The K-band emission of the weaker radio component appears extended,
whereas the emission from the brighter radio component is consistent with a
point source. Hubble Space Telescope F160W-band observations with the NICMOS
instrument confirms this. A redshift of 2.064 is found for the brighter
component, using the LRIS instrument on the W.M.Keck-II Telescope. The
probability that B0827+525 consists of two unrelated compact flat-spectrum
radio sources is ~3%, although the presence of similar substructure in both
component might reduce this.
  We discuss two scenarios to explain this system: (i) CLASS B0827+525 is a
`dark lens' system or (ii) B0827+525 is a binary radio-loud quasar. B0827+525
has met all criteria that thus far have in 100% of the cases confirmed a source
as an indisputable gravitational lens system. Despite this, no lens galaxy has
been detected with m_F160W<=23 mag. Hence, we might have found the first binary
radio-loud quasar. At this moment, however, we feel that the `dark lens'
hypothesis cannot yet be fully excluded.

</DOC>
<DOC>
<DOCNO> 170795 </DOCNO>
Luttinger model approach to interacting one-dimensional fermions in a


  A model of interacting one--dimensional fermions confined to a harmonic trap
is proposed. The model is treated analytically to all orders of the coupling
constant by a method analogous to that used for the Luttinger model. As a first
application, the particle density is evaluated and the behavior of Friedel
oscillations under the influence of interactions is studied. It is found that
attractive interactions tend to suppress the Friedel oscillations while strong
repulsive interactions enhance the Friedel oscillations significantly. The
momentum distribution function and the relation of the model interaction to
realistic pair interactions are also discussed.

</DOC>
<DOC>
<DOCNO> 72082 </DOCNO>
Heavy Flavour Physics: On Its More Than 50 Years Of History, Its Future


  After a reminder about how $\Delta S\neq 0$ physics has been instrumental for
the development of the Standard Model I sketch theoretical technologies for
dealing with nonperturbative QCD in heavy flavour decays and state predictions
for CP odd effects as they were made in 1998. I review the exciting
developments in heavy flavour physics as presented at this conference. A
central message is presented in the `Rio Manifesto' where I recapitulate the
lessons we have learnt from charm physics, point out the special role future
dedicated charm studies can play in revealing the presence of New Physics and
give an introduction to the relevant phenomenology focussed on CP studies.

</DOC>
<DOC>
<DOCNO> 121469 </DOCNO>
Emission from Bow Shocks of Beamed Gamma-Ray Bursts


  Beamed gamma-ray burst (GRB) sources produce a bow shock in their gaseous
environment. The emitted flux from this bow shock may dominate over the direct
emission from the jet for lines of sight which are outside the angular radius
of the jet emission, theta. The event rate for these lines of sight is
increased by a factor of 260*(theta/5_degrees)^{-2}. For typical GRB
parameters, we find that the bow shock emission from a jet with half-angle of
about 5 degrees is visible out to tens of Mpc in the radio and hundreds of Mpc
in the X-rays. If GRBs are linked to supernovae, studies of peculiar supernovae
in the local universe should reveal this non-thermal bow shock emission for
weeks to months following the explosion.

</DOC>
<DOC>
<DOCNO> 119039 </DOCNO>
On the ongoing multiple blowout in NGC 604


  Several facts regarding the structure of NGC 604 are examined here. The three
main cavities, produced by the mechanical energy from massive stars which in
NGC 604 are spread over a volume of 10$^6$ pc$^3$, are shown here to be
undergoing blowout into the halo of M33. High resolution long slit spectroscopy
is used to track the impact from massive stars while HST archive data is used
to display the asymmetry of the nebula.
  NGC 604 is found to be a collection of photoionized filaments and sections of
shells in direct contact with the thermalized matter ejected by massive stars.
The multiple blowout events presently drain the energy injected by massive
stars and thus the densest photoionized gas is found almost at rest and is
expected to suffer a slow evolution.

</DOC>
<DOC>
<DOCNO> 83280 </DOCNO>
Online Correction of Dispersion Error in 2D Waveguide Meshes


  An elastic ideal 2D propagation medium, i.e., a membrane, can be simulated by
models discretizing the wave equation on the time-space grid (finite difference
methods), or locally discretizing the solution of the wave equation (waveguide
meshes). The two approaches provide equivalent computational structures, and
introduce numerical dispersion that induces a misalignment of the modes from
their theoretical positions. Prior literature shows that dispersion can be
arbitrarily reduced by oversizing and oversampling the mesh, or by adpting
offline warping techniques. In this paper we propose to reduce numerical
dispersion by embedding warping elements, i.e., properly tuned allpass filters,
in the structure. The resulting model exhibits a significant reduction in
dispersion, and requires less computational resources than a regular mesh
structure having comparable accuracy.

</DOC>
<DOC>
<DOCNO> 151867 </DOCNO>
Light-cone gauge integrals: Prescriptionlessness at two loops


  The only calculations performed beyond one-loop level in the light-cone gauge
make use of the Mandelstam-Leibbrandt (ML) prescription in order to circumvent
the notorious gauge dependent poles. Recently we have shown that in the context
of negative dimensional integration method (NDIM) such prescription can be
altogether abandoned, at least in one-loop order calculations. We extend our
approach, now studying two-loop integrals pertaining to two-point functions.
While previous works on the subject present only divergent parts for the
integrals, we show that our prescriptionless method gives the same results for
them, besides finite parts for arbitrary exponents of propagators.

</DOC>
<DOC>
<DOCNO> 14008 </DOCNO>
Temporally disordered Ising models


  We present a study of the influence of different types of disorder on systems
in the Ising universality class by employing both a dynamical field theory
approach and extensive Monte Carlo simulations. We reproduce some well known
results for the case of quenched disorder (random temperature and random
field), and analyze the effect of four different types of time-dependent
disorder scarcely studied so far in the literature. Some of them are of obvious
experimental and theoretical relevance (as for example, globally fluctuating
temperatures or random fields). All the predictions coming from our field
theoretical analysis are fully confirmed by extensive simulations in two and
three dimensions, and novel qualitatively different, non-Ising transitions are
reported. Possible experimental setups designed to explore the described
phenomenologies are also briefly discussed.

</DOC>
<DOC>
<DOCNO> 71342 </DOCNO>
Feynman-Schwinger Representation method for bound states


  In nuclear and particle physics one is often faced with problems where
perturbation theory is not applicable. An example of this is the description of
bound states. Therefore, an exact solution of field theory to all orders is an
unavoidable and interesting problem. Path integrals provide a framework for
exact solutions in field theory. In this talk I will present an economical
method of evaluating path integrals using the Feynman-Schwinger representation
(FSR).

</DOC>
<DOC>
<DOCNO> 117237 </DOCNO>
Evanescent oscillations in accelerating structures


  Results of our investigations of the properties of the electromagnetic
oscillations in the resonators based on the periodic waveguides are
represented. These results point out on the possibility of existing in resonant
cavities the new type of eigen oscillations based on the evanescent waves. Such
oscillations do not exist in the smooth waveguides. They have a longitudinal
distribution of electromagnetic field with decreasing (increasing) dependence
on the coordinate. We discuss the using of such oscillations for bunching and
accelerating of electron beams.

</DOC>
<DOC>
<DOCNO> 70599 </DOCNO>
Froissart-Martin bound in spaces with compact extra dimensions


  We generalize the Froissart-Martin upper bound for the scattering amplitude
in spaces with compactified extra dimensions.

</DOC>
<DOC>
<DOCNO> 121489 </DOCNO>
The strength and width of Fe Kalpha lines in Seyferts and their


  We study properties of Fe K lines of a large sample of Seyfert 1s observed by
ASCA. Fits with power laws and Gaussian lines yield the average linewidth and
equivalent width of 0.22+-0.03 keV and 0.13+-0.01 keV, respectively. Thus, the
typical lines are weak and narrow. We then obtain the average line profile of
all our spectra, and find it to consist of a narrow core and blue and red
wings, with the red wing being much weaker than that of, e.g., MCG-6-30-15. We
obtain three average spectra of Seyferts grouped according to the hardness, and
find the equivalent width of the core (originating in a remote medium) to be
about 50 eV in all three cases. The wings are well fitted by a broad line from
a disc with strong relativistic effects. Its equivalent width correlates with
the slope, increasing from ~70 eV for the hardest spectrum to ~120 eV for the
softest one. The inner disc radius decreases correspondingly from ~40 to ~10
gravitational radii, and the fitted disc inclination is ~45 degrees. The
obtained correlation between the slope and the strength of the broad Fe K line
is found to be consistent with the previously found correlation of the slope
and Compton reflection.

</DOC>
<DOC>
<DOCNO> 10362 </DOCNO>
Exact renormalization group and applications to disordered problems:


  We develop a systematic multi-local expansion of the Polchinski-Wilson exact
renormalization group (ERG) equation. Integrating out explicitly the non local
interactions, we reduce the ERG equation obeyed by the full interaction
functional to a flow equation for a function, its local part. This is done
perturbatively around fixed points, but exactly to any given order in the local
part. It is thus controlled, at variance with projection methods, e.g.
derivative expansions or local potential approximations. Our method is
well-suited to problems such as the pinning of disordered elastic systems,
previously described via functional renormalization group (FRG) approach based
on a hard cutoff scheme. Since it involves arbitrary cutoff functions, we
explicitly verify universality to ${\cal O} (\epsilon =4-D)$, both of the T=0
FRG equation and of correlations. Extension to finite temperature $T$ yields
the finite size ($L$) susceptibility fluctuations characterizing mesoscopic
behaviour $\bar{(\Delta \chi)^2} \sim L^\theta/T$, where $\theta$ is the energy
exponent. Finally, we obtain the universal scaling function to ${\cal
O}(\epsilon^{1/3})$ which describes the ground state of a domain wall in a
random field confined by a field gradient, compare with exact results and
variational method. Explicit two loop exact RG equations are derived and the
application to the FRG problem is sketched.

</DOC>
<DOC>
<DOCNO> 10972 </DOCNO>
Oscillations of rotating trapped Bose-Einstein condensates


  The tensor-virial method is applied for a study of oscillation modes of
uniformly rotating Bose-Einstein condensed gases, whose rigid body rotation is
supported by an vortex array. The second order virial equations are derived in
the hydrodynamic regime for an arbitrary external harmonic trapping potential
assuming that the condensate is a superfluid at zero temperature. The
axisymmetric equilibrium shape of the condensate is determined as a function of
the deformation of the trap; its domain of stability is bounded by the
constraint $\Omega<1$ on the rotation rate (measured in units of the trap
frequency $\omega_0$.) The oscillations of the axisymmetric condensate are
stable with respect to the transverse-shear, toroidal and quasi-radial modes of
oscillations, corresponding to the $l= 2$, $| m| = 0,1,2 $ surface
deformations. In non-axisymmetric traps, the equilibrium constrains the
(dimensionless) deformation in the plane orthogonal to the rotation to the
domain $A_2 > \Omega^2$ with $\Omega< 1$. The second harmonic oscillation modes
in non-axisymmetric traps separate into two classes which have even or odd
parity with respect to the direction of the rotation axis. Numerical solutions
show that these modes are stable in the parameter domain where equilibrium
figures exist.

</DOC>
<DOC>
<DOCNO> 40268 </DOCNO>
How the sun shines


  This historical essay describes the struggle to understand how the sun
shines. The story begins with the disagreement between Kelvin and Darwin over
the age of the sun in the middle of the 19th century and continues through the
revelations of solar neutrino experiments at the conclusion of the 20th
century.

</DOC>
<DOC>
<DOCNO> 152221 </DOCNO>
Mass zeros in the one-loop effective actions of QED in 1+1 and 3+1


  It is known that the one-loop effective action of ${QED}_2$ is a quadratic in
the field strength when the fermion mass is zero: all potential higher order
contributions beyond second order vanish. For nonzero fermion mass it is shown
that this behavior persists for a general class of fields for at least one
value of the fermion mass when the external field's flux $\Phi$ satisfies
$0<|e\Phi|<2\pi$. For ${QED}_4$ with (anti-) self-dual fields the mass-shell
renormalized one-loop effective action vanishes for at least one value of the
fermion mass provided a plausible zero-mass limit exists.

</DOC>
<DOC>
<DOCNO> 118493 </DOCNO>
Deeply penetrating banded zonal flows in the solar convection zone


  Helioseismic observations have detected small temporal variations of the
rotation rate below the solar surface corresponding to the so-called `torsional
oscillations' known from Doppler measurements of the surface. These appear as
bands of slower and faster than average rotation moving equatorward. Here we
establish, using complementary helioseismic observations over four years from
the GONG network and from the MDI instrument on board SOHO, that the banded
flows are not merely a near-surface phenomenon: rather they extend downward at
least 60 Mm (some 8% of the total solar radius) and thus are evident over a
significant fraction of the nearly 200 Mm depth of the solar convection zone.

</DOC>
<DOC>
<DOCNO> 178970 </DOCNO>
Statistical evolution of isotope composition of nuclear fragments


  Calculations within the statistical multifragmentation model show that the
neutron content of intermediate mass fragments can increase in the region of
liquid-gas phase transition in finite nuclei. The model predicts also
inhomogeneous distributions of fragments and their isospin in the freeze-out
volume caused by an angular momentum and external long-range Coulomb field.
These effects can take place in peripheral nucleus-nucleus collisions at
intermediate energies and lead to neutron-rich isotopes produced in the
midrapidity kinematic region.

</DOC>
<DOC>
<DOCNO> 40072 </DOCNO>
Testing CP Conservation at KLOE


  A proposal for maintaining CP conservation in $K_{L}^{0}$ decays is resumed,
by adding a heterodox hypothesis. One recovers a consistent picture with a
$2\pi$ $K_{L}^{0}$ decay branching ratio proportional to the vertical
$K_{L}^{0}$ displacement. This can be clearly tested at the KLOE experiment,
where important vertical $K_{L}^{0}$ displacements occur.

</DOC>
<DOC>
<DOCNO> 11009 </DOCNO>
Localization and entanglement of two interacting electrons in a


  The localization of two interacting electrons in a coupled-quantum-dots
semiconductor structure is demonstrated through numerical calculations of the
time evolution of the two-electron wave function including the Coulomb
interaction between the electrons. The transition from the ground state to a
localized state is induced by an external, time-dependent, uniform electric
field. It is found that while an appropriate constant field can localize both
electrons in one of the wells, oscillatory fields can induce roughly equal
probabilities for both electrons to be localized in either well, generating an
interesting type of localized and entangled state. We also show that shifting
the field suddenly to an appropriate constant value can maintain in time both
types of localization.

</DOC>
<DOC>
<DOCNO> 122760 </DOCNO>
High-Redshift Galaxy Outflows and the Formation of Dwarf Galaxies


  We examine the effects of galaxy outflows on the formation of dwarf galaxies
in numerical simulations of the high-redshift Universe. Using a Smoothed
Particle Hydrodynamic code, we conduct two detailed simulations of a (5.2
Mpc/h)^3 comoving volume of the Universe. In both simulations we implement
simple, well-motivated models of galaxy identification and star formation,
while our second simulation also includes a simple ``blow-out'' model of galaxy
outflows in which supernova driven winds from newly formed disk galaxies
punch-out and shock the intergalactic medium while leaving the host galaxies
intact. A direct comparison between these simulations suggests that there are
two major mechanisms by which outflows affect dwarf formation. Firstly, the
formation of an outflow slows down the further accretion of gas onto a galaxy,
causing an overall decrease of approximately 50% in the total gas mass accreted
by the objects in our simulations. Additionally, our simulations uncover a
significant population of approximately 10^9 solar mass objects whose formation
is suppressed by the mechanism of ``baryonic stripping,'' in which outflows
from early galaxies strip the gas out of nearby overdense regions that would
have otherwise later formed into dwarf galaxies. This mechanism may be
important in explaining the observed discrepancy between the number of dwarf
galaxies predicted and observed in the local group and provide a natural
explanation for the formation of empty halos which may be required by the
existence of the extremely gas-poor extra-galactic High-Velocity Clouds.

</DOC>
<DOC>
<DOCNO> 122304 </DOCNO>
The Optical Extragalactic Background Light from Resolved Galaxies


  We discuss the ultraviolet to near-IR galaxy counts from the deepest imaging
surveys, including the northern and southern Hubble Deep Fields. The
logarithmic slope of the galaxy number-magnitude relation is flatter than 0.4
in all seven UBVIJHK optical bandpasses at faint magnitudes, i.e. the light
from resolved galaxies has converged from the UV to the near-IR. Most of the
galaxy contribution to the extragalactic background light (EBL) comes from
relatively bright, low-redshift objects (50% at V_AB<21 and 90% at V_AB<25.5).
We find a lower limit to the surface brightness of the optical EBL of about 15
nW/m^2/sterad, comparable to the intensity of the far-IR background from COBE
data. Diffuse light, lost because of surface brightness selection effects, may
add substantially to the EBL.

</DOC>
<DOC>
<DOCNO> 119082 </DOCNO>
Temporal Evolution of X-ray Lags in Cygnus X-1


  We present the long term evolution of the frequency-dependent X-ray time lags
of the black hole candidate Cygnus X-1 as measured in 1996 and 1998 with the
Rossi X-ray Timing Explorer (RXTE). Lag spectra measured during the 1996 June
soft state are very similar to those seen during 1996 December and most of 1998
while Cyg~X-1 was in its hard state. During state transitions, however, the
shape and magnitude of the X-ray lag is highly variable and tends to be much
larger than outside of the state transitions. This behavior is most obvious in
the 1--10 Hz band. The increase of the X-ray lag during the state transitions
might be related to the formation and destruction of the synchrotron radiation
emitting outflows present during the hard state.

</DOC>
<DOC>
<DOCNO> 102835 </DOCNO>
Force in Kappa-Deformed Relativistic Dynamics


  We consider the physical implications of various choices of the
three-momentum basis in the kappa-deformed Poincare algebra. In particular, we
find that the energy dependence of the velocity of a kappa-particle leads to
unexpected features in kappa-deformed kinematics. We also discuss the notion of
kappa-deformed dynamics, and as a tool example we investigate the motion of a
kappa-deformed particle under the action of a constant force.

</DOC>
<DOC>
<DOCNO> 69788 </DOCNO>
Dynamical Formation of Horizons in Recoiling D Branes


  A toy calculation of string/D-particle interactions within a world-sheet
approach indicates that quantum recoil effects - reflecting the gravitational
back-reaction on space-time foam due to the propagation of energetic particles
- induces the appearance of a microscopic event horizon, or `bubble', inside
which stable matter can exist. The scattering event causes this horizon to
expand, but we expect quantum effects to cause it to contract again, in a
`bounce' solution. Within such `bubbles', massless matter propagates with an
effective velocity that is less than the velocity of light in vacuo, which may
lead to observable violations of Lorentz symmetry that may be tested
experimentally. The conformal invariance conditions in the interior geometry of
the bubbles select preferentially three for the number of the spatial
dimensions, corresponding to a consistent formulation of the interaction of D3
branes with recoiling D particles, which are allowed to fluctuate independently
only on the D3-brane hypersurface.

</DOC>
<DOC>
<DOCNO> 116426 </DOCNO>
The Stern-Gerlach interaction between a traveling particle and a time


  The general expression of the Stern-Gerlach force is deduced for a charged
particle, endowed with a magnetic moment, which travels inside a time varying
magnetic field. Then, the energy integral of the Stern-Gerlach force is
evaluated in the case of a particle crossing a TE rf cavity with its magnetic
moment oriented in different ways with respect as the cavity axis. We shall
demonstrate that appropriate choices of the cavity characteristics and of the
spin orientation confirm the possibility of separating in energy the opposite
spin states of a fermion beam circulating in a storage ring and, in addition,
make feasible an absolute polarimeter provide that a parametric converter
acting between two coupled cavities is implemented

</DOC>
<DOC>
<DOCNO> 12342 </DOCNO>
Experimental evidence for a spin gap in the s=1/2 quantum


  Magnetic properties of the natural mineral Cu$_2$(OH)$_2$CO$_3$ (malachite)
were investigated through DC and AC susceptibility measurements. The analysis
of the low-temperature part reveals a quantum spin-gap behavior with $\Delta
\approx 130 K$. Consistently with the crystal structure, the magnetic
susceptibility can be accurately described by a model of alternating chain. The
non-frustrating residual inter-chain magnetic couplings, describing a sort of
dimerized square planar lattice, are not strong enough to push the system
towards a long-range ordered ground state, in good agreement with recent
theoretical studies.

</DOC>
<DOC>
<DOCNO> 121212 </DOCNO>
Log N - Log S Distributions of Accreting and Cooling Isolated Neutron


  We model populations of isolated neutron stars in the Galaxy following their
orbital and magneto-rotational evolution. It is shown that accretors become
more abundant than coolers at fluxes below $\sim 10^{-13}$ erg cm$^{-2}$
s$^{-1},$ and one can predict that about one accreting neutron star per square
degree should be observed at the Chandra and Newton flux limits of $\sim
10^{-16}$ erg cm$^{-2}$ s$^{-1}.$ The soft ROSAT sources associated with
isolated neutron stars can be relatively young cooling objects only if the
neutron star birth rate in the Solar vicinity during the last $\sim 10^6$ yr is
higher than that inferred from radiopulsar observations.

</DOC>
<DOC>
<DOCNO> 152504 </DOCNO>
D-branes and vacuum periodicity


  The superstring/M-theory suggests the Born-Infeld type modification of the
classical gauge field lagrangian. We discuss how this changes topological
issues related to vacuum periodicity in the SU(2) theory in four spacetime
dimensions. A new feature, which is due to the breaking of scale invariance by
the non-Abelian Born-Infeld (NBI) action, is that the potential barrier between
the neighboring vacua is lowered to a finite height. At the top of the barrier
one finds an infinite family of sphaleron-like solutions mediating transitions
between different topological sectors. We review these solutions for two
versions of the NBI action: with the ordinary and symmetrized trace. Then we
show the existence of sphaleron excitations of monopoles in the NBI theory with
the triplet Higgs. Soliton solutions in the constant external Kalb-Ramond field
are also discussed which correspond to monopoles in the gauge theory on
non-commutative space. A non-perturbative monopole solution for the
non-commutative U(1) theory is presented.

</DOC>
<DOC>
<DOCNO> 9787 </DOCNO>
Quantum statistical metastability for a finite spin


  We study quantum-classical escape-rate transitions for uniaxial and biaxial
models with finite spins S=10 (such as Mn_12Ac and Fe_8) and S=100 by a direct
numerical approach. At second-order transitions the level making a dominant
contribution into thermally assisted tunneling changes gradually with
temperature whereas at first-order transitions a group of levels is skipped.
For finite spins, the quasiclassical boundaries between first- and second-order
transitions are shifted, favoring a second-order transition: For Fe_8 in zero
field the transition should be first order according to a theory with S \to
\infty, but we show that there are no skipped levels at the transition.
Applying a field along the hard axis in Fe_8 makes transition the strongest
first order. For the same model with S=100 we confirmed the existence of a
region where a second-order transition is followed by a first-order transition
[X. Martines Hidalgo and E. M. Chudnovsky, J. Phys.: Condensed Matter (in
press)].

</DOC>
<DOC>
<DOCNO> 99484 </DOCNO>
Symplectic quotients by a nonabelian group and by its maximal torus


  This paper examines the relationship between the symplectic quotient X//G of
a Hamiltonian G-manifold X, and the associated symplectic quotient X//T, where
T is a maximal torus, in the case in which X//G is a compact manifold or
orbifold.
  The three main results are: a formula expressing the rational cohomology ring
of X//G in terms of the rational cohomology ring of X//T; an `integration'
formula, which expresses cohomology pairings on X//G in terms of cohomology
pairings on X//T; and an index formula, which expresses the indices of elliptic
operators on X//G in terms of indices on X//T.
  (The results of this paper are complemented by the results in a companion
paper, in which different techniques are used to derive formulae for cohomology
pairings on symplectic quotients X//T, where T is a torus, in terms of the
T-fixed points of X. That paper also gives some applications of the formulae
proved here.)

</DOC>
<DOC>
<DOCNO> 68800 </DOCNO>
Lifetime-difference pattern of heavy hadrons


  The preasymptotic effects originating from the four-quark operators are
disentangled from the other contributions by considering appropriate
combinations of inclusive decay rates. Under the assumption of the isospin and
heavy-quark symmetry, a set of relations connecting charmed and beauty decays
is obtained without invoking specific models. The results are compared with
other approaches and confronted with experiment.

</DOC>
<DOC>
<DOCNO> 85319 </DOCNO>
Nonassociative geometry: Towards discrete structure of spacetime


  In the framework of nonassociative geometry (hep-th/0003238) a unified
description of continuum and discrete spacetime is proposed. In our approach at
the Planck scales the spacetime is described as a so-called "diodular discrete
structure" which at large spacetime scales `looks like' a differentiable
manifold. After a brief review of foundations of nonassociative geometry,we
discuss the nonassociative smooth and discrete de Sitter spacetimes.

</DOC>
<DOC>
<DOCNO> 11726 </DOCNO>
Exact Scheme Independence


  Scheme independence of exact renormalization group equations, including
independence of the choice of cutoff function, is shown to follow from general
field redefinitions, which remains an inherent redundancy in quantum field
theories. Renormalization group equations and their solutions are amenable to a
simple formulation which is manifestly covariant under such a symmetry group.
Notably, the kernel of the exact equations which controls the integration of
modes acts as a field connection along the flow.

</DOC>
<DOC>
<DOCNO> 122423 </DOCNO>
Reanalysis of the high energy cutoff of the 1997 Mkn 501 TeV energy


  Data taken with the HEGRA system of imaging atmospheric Cherenkov telescopes
during the 1997 flares of Mkn 501 are reanalyzed using an algorithm providing
improved energy resolution. A resolution of 10% to 12% is obtained by
accounting for the variation of the Cherenkov light yield with the height of
the shower maximum in the atmosphere. The improved energy resolution is
particularly relevant for the study of the high-energy cutoff in the spectrum,
which might be caused by interactions with the intergalactic infrared
background radiation. The reanalysis presented here confirms the results
obtained in the previous analysis, but hints a steeper slope of the spectrum in
the region around 20 TeV.

</DOC>
<DOC>
<DOCNO> 100629 </DOCNO>
Rigorous Numerics for Partial Differential Equations: the


  We present a new topological method for the study of the dynamics of
dissipative PDE's. The method is based on the concept of the self-consistent
apriori bounds, which allows to justify rigorously the Galerkin projection. As
a result we obtain a low-dimensional system of ODE's subject to rigorously
controlled small perturbation from the neglected modes. To this ODE's we apply
the Conley index to obtain information about the dynamics of the PDE under
consideration. As an application we present a computer assisted proof of the
existence of fixed points for the Kuramoto-Sivashinsky equation.

</DOC>
<DOC>
<DOCNO> 170748 </DOCNO>
Storage of quantum dynamics on quantum states: a quasi-perfect


  We show how quantum dynamics (a unitary transformation) can be captured in
the state of a quantum system, in such a way that the system can be used to
perform, at a later time, the stored transformation almost perfectly on some
other quantum system. Thus programmable quantum gates for quantum information
processing are feasible if some small degree of imperfection is allowed. We
discuss the possibility of using this fact for securely computing a secret
function on a public quantum computer. Finally, our scheme for storage of
operations also allows for a new form of quantum remote control.

</DOC>
<DOC>
<DOCNO> 71530 </DOCNO>
Dynamics of O(N) chiral supersymmetry at finite energy density


  We consider an O(N) version of a massive, interacting, chiral supersymmetry
model solved exactly in the large N limit. We demonstrate that the system
approaches a stable attractor at high energy densities, corresponding to a
non-perturbative state for which the relevant field quanta are massless. The
state is one of spontaneously broken O(N), which, due to the influence of
supersymmetry, does not become restored at high energies. Introducing soft
supersymmetry breaking to the Lagrangian results in scalar masses at the soft
breaking scale m_s independent of the mass scale of supersymmetry mu, with even
smaller masses for the fermions.

</DOC>
<DOC>
<DOCNO> 40662 </DOCNO>
Window on Higgs Boson: Fourth Generation $b^\prime$ Decays Revisited


  Direct and indirect searches of the Higgs boson suggest that 113 GeV
$\lesssim m_H \lesssim$ 170 GeV is likely. With the LEP era over and the
Tevatron Run II search via $p\bar p \to WH+X$ arduous, we revisit a case where
$WH$ or $ZH +$ jets could arise via strong $b^\prime\bar b^\prime$ pair
production. In contrast to 10 years ago, the tight electroweak constraint on
$t^\prime$--$b^\prime$ (hence $t^\prime$--$t$) splitting reduces FCNC
$b^\prime\to bZ$, $bH$ rates, making $b^\prime\to cW$ naturally competitive.
Such a "cocktail solution" is precisely the mix that could evade the CDF search
for $b^\prime\to bZ$, and the $b^\prime$ may well be lurking below the top. In
light of the Higgs program, this two-in-one strategy should be pursued.

</DOC>
<DOC>
<DOCNO> 71626 </DOCNO>
Can the Cabibbo mixing originate from noncommutative extra dimensions?


  Treating hadronic flavor symmetries with quantum algebras U_q(su_n) leads to
interesting consequences such as: new mass sum rules for hadrons 1^-, (1/2)^+,
(3/2)^+ of improved accuracy; possibility to label different flavors
topologically - by torus winding number; properly fixed deformation parameter q
in case of baryons is linked in a simplest way to the Cabibbo angle \theta_C,
that suggests for \theta_C the exact value {\pi}/{14}. In this connection, we
discuss the possibility that this angle and the Cabibbo mixing as a whole take
its origin in noncommutativity of some additional, with regard to 3+1,
space-time dimensions.

</DOC>
<DOC>
<DOCNO> 152564 </DOCNO>
Rotational Perturbations in Neveu-Schwarz-Neveu-Schwarz String Cosmology


  First order rotational perturbations of the flat Friedmann-Robertson-Walker
(FRW) metric are considered in the framework of four dimensional
Neveu-Schwarz-Neveu-Schwarz (NS-NS) string cosmological models coupled with
dilaton and axion fields. The decay rate of rotation depends mainly upon the
dilaton field potential U. The equation for rotation imposes strong limitations
upon the functional form of U, restricting the allowed potentials to two: the
trivial case U=0 and a generalized exponential type potential. In these two
models the metric rotation function can be obtained in an exact analytic form
in both Einstein and string frames. In the potential-free case the decay of
rotational perturbations is governed by an arbitrary function of time while in
the presence of a potential the rotation tends rapidly to zero in both Einstein
and string frames.

</DOC>
<DOC>
<DOCNO> 118437 </DOCNO>
Radio Pulsars in Terzan 5


  We report on searches of the globular cluster Terzan 5 for low luminosity and
accelerated radio pulsars using the 64-m Parkes radio telescope. One new
millisecond pulsar, designated PSR J1748-2446C, was discovered, having a period
of 8.44ms. Timing measurements using the 76-m Lovell radio telescope at Jodrell
Bank show that it is a solitary pulsar and lies close to the core of the
cluster. We also present the results of timing measurements which show that the
longer-period pulsar PSR J1748-2444 (formerly known as PSR B1744-24B) lies 10
arcmin from the core of the cluster and is unlikely to be associated with the
cluster. We conclude that there are further pulsars to be detected in the
cluster.

</DOC>
<DOC>
<DOCNO> 99578 </DOCNO>
Pre-Lie algebras and the rooted trees operad


  A Pre-Lie algebra is a vector space L endowed with a bilinear product * : L
\times L to L satisfying the relation (x*y)*z-x*(y*z)= (x*z)*y-x*(z*y), for all
x,y,z in L. We give an explicit combinatorial description in terms of rooted
trees of the operad associated to this type of algebras and prove that it is a
Koszul operad.

</DOC>
<DOC>
<DOCNO> 120574 </DOCNO>
Measurements of solar irradiance and effective temperature as a probe of


  We argue that a variety of solar data suggest that the activity-cycle
timescale variability of the total irradiance, is produced by structural
adjustments of the solar interior. Assuming these adjustments are induced by
variations of internal magnetic fields, we use measurements of the total
irradiance and effective temperature over the period from 1978 to 1992, to
infer the magnitude and location of the magnetic field. Using an updated
stellar evolution model, which includes magnetic fields, we find that the
observations can be explained by fields whose peak values range from 120k to
2.3k gauss, located in the convection zone between $0.959R_{\sun}$ and
$0.997R_{\sun}$, respectively. The corresponding maximal radius changes, are 17
km when the magnetic field is located at $0.959R_{\sun}$ and 3 km when it is
located at $0.997R_{\sun}$. At these depths, the $W$ parameter(defined by
$\Delta \ln R / \Delta \ln L$, where $R$ and $L$ are the radius and luminosity)
ranges from 0.02 to 0.006. All these predictions are consistent with
helioseismology and recent measurements carried out by the MDI experiment on
SOHO.

</DOC>
<DOC>
<DOCNO> 13626 </DOCNO>
Percolation and Deconfinement in SU(2) Gauge Theory


  Cluster percolation and second order thermal phase transitions show an
amazing number of common features: power laws of the variables at criticality,
scaling relations of the critical exponents and universality of the critical
indices. Because of that, percolation theory seems to be an ideal framework to
devise a geometrical picture of a second order phase transition; the leading
characters of the phenomenon are ordered domains, whose size increases while
approaching the threshold until they fuse into a spanning structure, so that
the order from local becomes global. Such a geometrical picture is known to be
successful in the Ising model. The clusters are site-bond clusters, i.e. they
are built by joining nearest-neighbouring aligned spins with some
temperature-dependent bond probability. In this work we extend this result to a
wide variety of theories, from continuous Ising-like models to O(n) models. On
the grounds of these results, we devise a percolation picture for the confining
phase transition of SU(2) pure gauge theory, exploiting its analogies with the
Ising model. The cluster definition is obtained by constructing suitable
effective theories for SU(2), which admit an equivalent percolation
formulation.

</DOC>
<DOC>
<DOCNO> 83108 </DOCNO>
Applying Maxi-adjustment to Adaptive Information Filtering Agents


  Learning and adaptation is a fundamental property of intelligent agents. In
the context of adaptive information filtering, a filtering agent's beliefs
about a user's information needs have to be revised regularly with reference to
the user's most current information preferences. This learning and adaptation
process is essential for maintaining the agent's filtering performance. The AGM
belief revision paradigm provides a rigorous foundation for modelling rational
and minimal changes to an agent's beliefs. In particular, the maxi-adjustment
method, which follows the AGM rationale of belief change, offers a sound and
robust computational mechanism to develop adaptive agents so that learning
autonomy of these agents can be enhanced. This paper describes how the
maxi-adjustment method is applied to develop the learning components of
adaptive information filtering agents, and discusses possible difficulties of
applying such a framework to these agents.

</DOC>
<DOC>
<DOCNO> 70912 </DOCNO>
Semi-analytical calculation of QED radiative corrections to $e^+e^-\to


  In this dissertation, a complete calculation of QED radiative corrections is
presented for total cross sections and forward- backward asymmetries for
s-channel fermion pair production in e+e- annihilation with kinematical cuts to
the final state. This includes cuts on the maximal acollinearity angle
theta_acol and on the minimal energies E_min of the final state fermion pair
and on the cosine of the scattering angle of one fermion, cos{theta}. The
applied cuts pose a realistic alternative for leptonic final states compared to
cuts on the invariant mass squared s' of the fermion pair and on cos{theta}.
The new formulae and the analysis presented in this thesis for high energies
and luminosities form an essential building block for an upgrading of
two-fermion codes like ZFITTER for a future e+e- Linear Collider.

</DOC>
<DOC>
<DOCNO> 150597 </DOCNO>
Ramond-Ramond Field Radiation from Rotating Ellipsoidal Membranes


  We find a new stable rotator solution in D0-brane matrix mechanics. The
solution is interpreted as a D2/D0 brane bound state, constructed as a
transversely rotating ellipsoidal membrane with N D0-branes pinned over it.
  From the membrane point of view the attractive force of tension is exactly
cancelled by the repulsive centrifugal force. Dynamical properties of the
system are investigated, in particular the emission of spherical waves in the
different massless sectors of supergravity. We compute the RR 1-form
quadrupole, the RR 3-form dipole and the gravitational quadrupole radiation.
Also, we show that our non-singular classical solution is stable against small
perturbations in the initial conditions. Furthermore, we comment on a possible
fundamental particle interpretation of our system.

</DOC>
<DOC>
<DOCNO> 116976 </DOCNO>
Heavy-Ion Beam Acceleration of Two-Charge States from an Ecr Ion Source


  This paper describes a design for the front end of a superconducting (SC) ion
linac which can accept and simultaneously accelerate two charge states of
uranium from an ECR ion source. This mode of operation increases the beam
current available for the heaviest ions by a factor of two. We discuss the 12
MeV/u prestripper section of the Rare Isotope Accelerator (RIA) driver linac
including the LEBT, RFQ, MEBT and SC sections, with a total voltage of 112 MV.
The LEBT consists of two bunchers and electrostatic quadrupoles. The
fundamental frequency of both bunchers is half of the RFQ frequency. The first
buncher is a multiharmonic buncher, designed to accept more than 80% of each
charge state and to form bunches of extremely low longitudinal emittance (rms
emittance is lower than 0.2 keV/u nsec) at the output of the RFQ. The second
buncher is located directly in front of the RFQ and matches the velocity of
each charge-state bunch to the design input velocity of the RFQ. We present
full 3D simulations of a two-charge-state uranium beam including space charge
forces in the LEBT and RFQ, realistic distributions of all electric and
magnetic fields along the whole prestripper linac, and the effects of errors,
evaluated for several design options for the prestripper linac. The results
indicate that it is possible to accelerate two charge states while keeping
emittance growth within tolerable limits.

</DOC>
<DOC>
<DOCNO> 178745 </DOCNO>
Multifragmentation - what the data tell us about the different models


  We discuss what the presently collected data tell us about the mechanism of
multifragmentation by comparing the results of two different models, which
assume or show an opposite reaction scenario, with the recent high statistics
$4\pi$ experiments performed by the INDRA collaboration. We find that the
statistical multifragmentation model and the dynamical Quantum Molecular
Dynamics approach produce almost the same results and agree both quite well
with experiment. We discuss which observables may serve to overcome this
deadlock on the quest for the reaction mechanism. Finally we proof that even if
the system is in equilibrium, the fluctuation of the temperature due to the
smallness of the system renders the caloric curve useless for the proof of a
first order phase transition.

</DOC>
<DOC>
<DOCNO> 83309 </DOCNO>
Many uses, many annotations for large speech corpora: Switchboard and


  This paper discusses the challenges that arise when large speech corpora
receive an ever-broadening range of diverse and distinct annotations. Two case
studies of this process are presented: the Switchboard Corpus of telephone
conversations and the TDT2 corpus of broadcast news. Switchboard has undergone
two independent transcriptions and various types of additional annotation, all
carried out as separate projects that were dispersed both geographically and
chronologically. The TDT2 corpus has also received a variety of annotations,
but all directly created or managed by a core group. In both cases, issues
arise involving the propagation of repairs, consistency of references, and the
ability to integrate annotations having different formats and levels of detail.
We describe a general framework whereby these issues can be addressed
successfully.

</DOC>
<DOC>
<DOCNO> 10534 </DOCNO>
Stochastic boundary conditions in the deterministic Nagel-Schreckenberg


  We consider open systems where cars move according to the deterministic
Nagel-Schreckenberg rules and with maximum velocity ${v}_{max} > 1$, what is an
extension of the Asymmetric Exclusion Process (ASEP). It turns out that the
behaviour of the system is dominated by two features: a) the competition
between the left and the right boundary b) the development of so-called
"buffers" due to the hindrance an injected car feels from the front car at the
beginning of the system. As a consequence, there is a first-order phase
transition between the free flow and the congested phase accompanied by the
collapse of the buffers and the phase diagram essentially differs from that of
${v}_{max} = 1$ (ASEP).

</DOC>
<DOC>
<DOCNO> 84517 </DOCNO>
Fluctuations of Energy Density and Validity of Semiclassical Gravity


  From calculations of the variance of fluctuations and of the mean of the
energy density of a massless scalar field in the Minkowski vacuum as a function
of an intrinsic scale defined by the world function between two nearby points
(as used in point separation regularization) we show that, contrary to prior
claims, the ratio of variance to mean-squared being of the order unity does not
imply a failure of semiclassical gravity. It is more a consequence of the
quantum nature of the state of matter field than any inadequacy of the theory
of spacetime with quantum matter as source.

</DOC>
<DOC>
<DOCNO> 8479 </DOCNO>
Semiflexible polymer on an anisotropic Bethe lattice


  The mean square end-to-end distance of a N-step polymer on a Bethe lattice is
calculated. We consider semiflexible polymers placed on isotropic and
anisotropic lattices. The distance on the Cayley tree is defined by embedding
the tree on a sufficiently high dimensional Euclidean space considering that
every bend of the polymer defines a direction orthogonal to all the previous
ones. In the isotropic case, the result obtained for the mean square end-to-end
distance turns out to be identical to the one obtained for ideal chains without
immediate returns on an hypercubic lattice with the same coordination number of
the Bethe lattice. For the general case, we obtain the asymptotic behavior in
the semiflexible and also in the almost rigid limits.

</DOC>
<DOC>
<DOCNO> 119317 </DOCNO>
A catalogue of symbiotic stars


  We present a new catalogue of symbiotic stars. In our list we include 188
symbiotic stars as well as 28 objects suspected of being symbiotic. For each
star, we present basic observational material: coordinates, V and K magnitudes,
ultraviolet (UV), infrared (IR), X-ray and radio observations. We also list the
spectral type of the cool component, the maximum ionization potential observed,
references to finding charts, spectra, classifications and recent papers
discussing the physical parameters and nature of each object. Moreover, we
present the orbital photometric ephemerides and orbital elements of known
symbiotic binaries, pulsational periods for symbiotic Miras, Hipparcos
parallaxes and information about outbursts and flickering.

</DOC>
<DOC>
<DOCNO> 119253 </DOCNO>
Electrodynamic Structure of Outer Gap Accelerators: Invisibility of


  We study the structure of an outer-magnetospheric gap around a rotating
neutron star. Migratory electrons and positrons are accelerated by the electric
field exerted in the gap and radiate copious gamma-rays via curvature process.
Some of the gamma-rays materialize by colliding with the X-rays illuminating
the gap, leading to a pair production cascade. The replenished charges
partially screen the original acceleration field, which is self-consistently
solved from the Poisson equation, together with the Boltzmann equations for
gamma-rays and the continuity equations for particles. We demonstrate that it
is difficult to detect the TeV emission due to Compton upscatterings in the
gap, by the current ground-based telescopes.

</DOC>
<DOC>
<DOCNO> 39983 </DOCNO>
The Quark-Antiquark Asymmetry of the Nucleon Sea from $\Lambda$ and


  We present a general analysis of the spin transfer for $\Lambda$ and
$\bar{\Lambda}$ production in deep-inelastic scattering of polarized charged
leptons on the nucleon, and find that the pattern of different behaviors of
$\Lambda$ and $\bar{\Lambda}$ production observed by the E665 Collaboration
suggests the possibility of quark-antiquark asymmetries either in the quark to
$\Lambda$ fragmentation functions and/or in the quark and antiquark
distributions of the target proton. We also point out that the
strange-antistrange asymmetry of the nucleon sea may produce an observable
contribution to the different behaviors of $\Lambda$ and $\bar{\Lambda}$
production. We find that a softer $\bar{s}(x)$ than $s(x)$ as predicted by the
light-cone baryon-meson fluctuation model of intrinsic quark-antiquark pairs of
the nucleon sea might lead to a reasonable picture. However, the magnitude is
still too small to explain the E665 data and the conclusion has also strong
model-dependence. This may suggest the importance of quark-antiquark asymmetry
in the quark to $\Lambda$ fragmentation functions, provided that the E665 data
are confirmed.

</DOC>
<DOC>
<DOCNO> 12834 </DOCNO>
Overview: Brownian Motion and Dephasing due to Dynamical Disorder


  The motion of a particle under the influence of a dynamical disorder is
described by the DLD model. One motivation is to understand the motion of an
electron inside a metal; Another is to understand quantal Brownian motion. The
overview is based on a research report for 1996-1998.

</DOC>
<DOC>
<DOCNO> 12747 </DOCNO>
Effect of Long Range Disorder on Electron Motion in Two Dimensions


  We consider a two-dimensional electron gas with long range disorder. Assuming
that time reversal symmetry is broken either by an external magnetic field or,
as in the case of a delta-correlated random magnetic field, by the disorder
itself, we derive a supermatrix $\sigma $-model. As an intermediate step, we
provide a microscopic derivation of the ballistic $\sigma$-model, and find that
certain corrections to its usual form may become important. We then integrate
out degrees of freedom corresponding to short length scales to derive a
low-energy supermatrix $\sigma $-model. We find an extra term in the free
energy that couples to the correlator of local currents. Use of a proper
ultraviolet regularisation procedure that preserves gauge invariance indicates
that the contribution of the extra term seems finally to become irrelevant.
Within the scope of our analyis, we therefore do not find any deviation of the
scaling behaviour of the delta-correlated random magnetic field model from that
of the conventional unitary ensemble. We then generalize the discussion to
include models of even longer-ranged disorder, plus short-range disorder. When
the disorder is sufficiently long-ranged that the local currents become
delta-correlated, a new term appears in the free energy that does give rise to
logarithmic corrections to the conductivity. A renormalisation group analysis
of the free energy yields a scaling form for the diffusion coefficient which
contains both a positive correction, that represents classical superdiffusion,
and a negative correction, which is the usual weak localization correction. The
fact that both corrections are of the same order and opposite sign leads to the
interesting possibility of a quantum phase transition at weak disorder in two
dimensions, tuned by the relative disorder strengths.

</DOC>
<DOC>
<DOCNO> 150383 </DOCNO>
On the supersymmetric effective action of Matrix theory


  We present a simple derivation of the supersymmetric one-loop effective
action of SU(2) Matrix theory by expressing it in a compact exponential form
whose invariance under supersymmetry transformations is obvious. This result
clarifies the one-loop exactness of the leading v^4 interactions and the
absence of non-perturbative corrections.

</DOC>
<DOC>
<DOCNO> 101662 </DOCNO>
Total convergence or general divergence in Small Divisors


  We study generic holomorphic families of dynamical systems presenting
problems of small divisors with fixed arithmetic. We prove that we have
convergence for all parameter values or divergence everywhere except for an
exceptional set in the potential theory sense. We illustrate this general
principle in different problems of small divisors.

</DOC>
<DOC>
<DOCNO> 11349 </DOCNO>
Photoluminescence from fractional quantum Hall systems: Role of


  The photoluminescence (PL) spectrum of a two-dimensional electron gas (2DEG)
in the fractional quantum Hall regime is studied as a function of the
separation $d$ between the electron and valence hole layers. The abrupt change
in the response of the 2DEG to the optically injected hole at $d$ of the order
of the magnetic length $\lambda$ results in a complete reconstruction of the PL
spectrum. At $d<\lambda$, the hole binds one or two electrons to form neutral
($X$) or charged ($X^-$) excitons, and the PL spectrum probes the lifetimes and
binding energies of these states rather than the original correlations of the
2DEG. At $d>2\lambda$, depending on the filling factor $\nu$, the hole either
decouples from the 2DEG to form an ``uncorrelated'' state $h$ or binds one or
two Laughlin quasielectrons (QE) to form fractionally charged excitons $h$QE or
$h$QE$_2$. The strict optical selection rules for bound states are formulated,
and the only optically active ones turn out to be $h$, $h$QE* (an excited state
of the dark $h$QE), and $h$QE$_2$. The ``anyon exciton'' $h$QE$_3$ suggested in
earlier studies is neither stable nor radiative at any value of $d$. The
critical dependence of the stability of different states on the presence of
QE's in the 2DEG explains the observed anomalies in the PL spectrum at
$\nu={1\over3}$ and ${2\over3}$.

</DOC>
<DOC>
<DOCNO> 170618 </DOCNO>
An expectation value expansion of Hermitian operators in a discrete


  We discuss a real-valued expansion of any Hermitian operator defined in a
Hilbert space of finite dimension N, where N is a prime number, or an integer
power of a prime. The expansion has a direct interpretation in terms of the
operator expectation values for a set of complementary bases. The expansion can
be said to be the complement of the discrete Wigner function.
  We expect the expansion to be of use in quantum information applications
since qubits typically are represented by a discrete, and finite-dimensional
physical system of dimension N=2^p, where p is the number of qubits involved.
As a particular example we use the expansion to prove that an intermediate
measurement basis (a Breidbart basis) cannot be found if the Hilbert space
dimension is 3 or 4.

</DOC>
<DOC>
<DOCNO> 150536 </DOCNO>
p-Gerbes and Extended Objects in String Theory


  p-Gerbes are a generalization of bundles that have (p+2)-form field
strengths. We develop their properties and use them to show that every theory
of p-gerbes can be reinterpreted as a gauge theory containing p-dimensional
extended objects. In particular, we show that every closed (p+2)-form with
integer cohomology is the field strength for a gerbe, and that every p-gerbe is
equivalent to a bundle with connection on the space of p-dimensional
submanifolds of the original space. We also show that p-gerbes are equivalent
to sheaves of (p-1)-gerbes, and use this to define a K-theory of gerbes. This
K-theory classifies the charges of (p+1)-form connections in the same way that
bundle K-theory classifies 1-form connections.

</DOC>
<DOC>
<DOCNO> 84597 </DOCNO>
Cosmological two-fluid thermodynamics


  We reveal unifying thermodynamic aspects of so different phenomena as the
cosmological electron-positron annihilation, the evaporation of primordial
black holes with a narrow mass range, and the ``deflationary'' transition from
an initial de Sitter phase to a subsequent standard
Friedmann-Lema\^{\i}tre-Robertson-Walker begin (FLRW) behavior.

</DOC>
<DOC>
<DOCNO> 170345 </DOCNO>
Effective Hamiltonian Approach to the Master Equation


  A method of exactly solving the master equation is presented in this letter.
The explicit form of the solution is determined by the time evolution of a
composite system including an auxiliary system and the open system in question.
The effective Hamiltonian governing the time evolution of the composed system
are derived from the master equation. Two examples, the dissipative two-level
system and the damped harmonic oscillator, are presented to illustrate the
solving procedure. 
  PACS number(s): 05.30.-d, 05.40.+j, 42.50.Ct

</DOC>
<DOC>
<DOCNO> 170755 </DOCNO>
Security of Quantum Key Distribution with Entangled Photons Against


  Security of the Ekert protocol is proven against individual attacks where an
eavesdropper is allowed to share any density matrix with the two communicating
parties. The density matrix spans all of the photon number states of both
receivers, as well as a probe state of arbitrary dimensionality belonging to
the eavesdropper. Using this general eavesdropping strategy, we show that the
Shannon information on the final key, after error correction and privacy
amplification, can be made exponentially small. This is done by finding a bound
on the eavesdropper's average collision probability. We find that the average
collision probability for the Ekert protocol is the same as that of the BB84
protocol for single photons, indicating that there is no analog in the Ekert
protocol to photon splitting attacks. We then compare the communication rate of
both protocols as a function of distance, and show that the Ekert protocol has
potential for much longer communication distances, up to 170km, in the presence
of realistic detector dark counts and channel loss. Finally, we propose a
slightly more complicated scheme based on entanglement swapping that can lead
to even longer distances of communication. The limiting factor in this new
scheme is the fiber loss, which imposes very slow communication rates at longer
distances.

</DOC>
<DOC>
<DOCNO> 71561 </DOCNO>
Solution of the Boltzmann equation for gluons after a heavy ion


  A non-linear Boltzmann equation describing the time evolution of a partonic
system in the central rapidity region after a heavy ion collision is solved
numerically. A particular model of the collinear logarithmic divergences due to
small angle scattering is employed in the numerical solution. The system is
followed until it reaches kinetic equilibrium where the equilibration time,
temperature and chemical potential are determined for both RHIC and LHC.

</DOC>
<DOC>
<DOCNO> 67965 </DOCNO>
Probing The Structure of Space-Time with Cosmic Rays


  The study of the interactions of Cosmic Rays (CR's) with universal diffuse
background radiation can provide very stringent tests of the validity of
Special Relativity. The interactions we consider are the ones characterized by
well defined energy thresholds whose energy position can be predicted on the
basis of Special Relativity. We argue that the experimental confirmation of the
existence of these thresholds can in principle put very stringent limits on the
scale where Special Relativity and/or continuity of space-time may possibly
break down.

</DOC>
<DOC>
<DOCNO> 69068 </DOCNO>
B-ball Dark Matter and Baryogenesis


  It has been recently suggested that stable, supersymmetric B-balls formed in
the early universe could not only be the dark matter at the present epoch, but
also be responsible for baryogenesis by their partial evaporation at high
temperatures. We reinvestigate the efficiency of B-ball baryogenesis and find
it to be limited by the diffusion of baryon number away from the B-balls.
Successful baryogenesis may only occur for B-balls with charges Q\simle 10^{20}
- 5\times 10^{23}, which is close to the observational lower limits on the Q of
a significant B-ball dark matter component. We also present some cosmological
constraints on the abundances of larger B-balls in the early universe.

</DOC>
<DOC>
<DOCNO> 150982 </DOCNO>
The Microscopic Spectral Density of the Dirac Operator derived from


  The microscopic spectral correlations of the Dirac operator in Yang-Mills
theories coupled to fermions in (2+1) dimensions can be related to three
universality classes of Random Matrix Theory. In the microscopic limit the
Orthogonal Ensemble (OE) corresponds to a theory with 2 colors and fermions in
the fundamental representation and the Symplectic Ensemble (SE) corresponds to
an arbitrary number of colors and fermions in the adjoint representation. Using
a new method of Widom, we derive an expression for the two scalar kernels which
through quaternion determinants give all spectral correlation functions in the
Gaussian Orthogonal Ensemble (GOE) and in the the Gaussian Symplectic Ensemble
(GSE) with all fermion masses equal to zero. The result for the GOE is valid
for an arbitrary number of fermions while for the GSE we have results for an
even number of fermions.

</DOC>
<DOC>
<DOCNO> 71090 </DOCNO>
Precision of inflationary predictions and recent CMB anisotropy data


  Inflationary predictions of the cosmic microwave background anisotropy are
often based on the slow-roll approximation. We study the precision of these
predictions and compare them with the recent data from BOOMERanG and MAXIMA-1.

</DOC>
<DOC>
<DOCNO> 85643 </DOCNO>
Unified field theory from one-particle physics


  This work starts with the observation of a certain "rule" (up to now
unexplored) in the fundamental laws of Nature. We show some evidence of this,
and formulate it as a fundamental principle which exhibits a number physical
consequences. In particular, a new, very simple and extremely aesthetic unified
model, which includes supersymmetry and supergravity, naturally arises from
this principle, together with some new "physics". Furthermore, the new
interpretation of Kaluza-Klein extra dimensions we advocate here provides a
natural argument for dimensional reduction, and the agreement with the observed
phenomenology is recovered. In the high energy regime, a new physics is
expected. Consequences in QFT are shortly commented. Finally, we observe a
structure of "levels" and formulate a general conjecture about such a concept.

</DOC>
<DOC>
<DOCNO> 84996 </DOCNO>
Canonical Noether symmetries and commutativity properties for gauge


  For a dynamical system defined by a singular Lagrangian, canonical Noether
symmetries are characterized in terms of their commutation relations with the
evolution operators of Lagrangian and Hamiltonian formalisms. Separate
characterizations are given in phase space, in velocity space, and through an
evolution operator that links both spaces.

</DOC>
<DOC>
<DOCNO> 9228 </DOCNO>
The Type-problem on the Average for random walks on graphs


  When averages over all starting points are considered, the Type Problem for
the recurrence or transience of a simple random walk on an inhomogeneous
network in general differs from the usual "local" Type Problem. This difference
leads to a new classification of inhomogeneous discrete structures in terms of
{\it recurrence} and {\it transience} {\it on the average}, describing their
large scale topology from a "statistical" point of view. In this paper we
analyze this classification and the properties connected to it, showing how the
average behavior affects the thermodynamic properties of statistical models on
graphs.

</DOC>
<DOC>
<DOCNO> 13015 </DOCNO>
Heterogeneous condensation on the centers with continuous activity in


  A system with a metastable phase and a pseudo continuous set of the
heterogeneous centers is considered. An analytical theory for kinetics of the
process of condensation in such a system is constructed. The free energy of
formation of the critical embryo is assumed to be known in the capillary
(macroscopic) approach as well as the solvatation energy of the embryo. The
theory is based on the quasistationary approximation for the nucleation rate
which has been justified analytically. An effective iteration procedure is
presented. The iterations are calculated analytically. The approximate
universal form of the spectrum is established.

</DOC>
<DOC>
<DOCNO> 120033 </DOCNO>
Gas Rich Dwarfs from the PSS-II III. HI Profiles and Dynamical Masses


  We present Arecibo neutral hydrogen data on a sample of optically selected
dwarf galaxies. The sample ranges in HI mass from 10^6 M_sun to 5x10^9 M_sun,
with a mean of 7.9x10^8 M_sun. Using estimated HI radii, the HI surface
densities range from 0.6 to 20 M_sun pc^-2, all well below the critical
threshold for star formation (Kennicutt 1998). M_HI/L values of the LSB dwarfs
range from 0.3 to 12 with a mean value of 2.0. Dynamical masses, calculated
from the HI profile widths, range from 10^8 M_sun to 10^11 M_sun. There is a
strong correlation between optical luminosity and dynamical mass for LSB dwarfs
implying that the dark matter (whether baryonic or non-baryonic) follows the
detectable baryonic matter.

</DOC>
<DOC>
<DOCNO> 9158 </DOCNO>
Anomalous diffusion associated with nonlinear fractional derivative


  We consider the $d=1$ nonlinear Fokker-Planck-like equation with fractional
derivatives $\frac{\partial}{\partial t}P(x,t)=D
\frac{\partial^{\gamma}}{\partial x^{\gamma}}[P(x,t) ]^{\nu}$. Exact
time-dependent solutions are found for $ \nu = \frac{2-\gamma}{1+ \gamma}$
($-\infty<\gamma \leq 2$). By considering the long-distance {\it asymptotic}
behavior of these solutions, a connection is established, namely
$q=\frac{\gamma+3}{\gamma+1}$ ($0<\gamma \le 2$), with the solutions optimizing
the nonextensive entropy characterized by index $q$ . Interestingly enough,
this relation coincides with the one already known for L\'evy-like
superdiffusion (i.e., $\nu=1$ and $0<\gamma \le 2$). Finally, for
$(\gamma,\nu)=(2, 0)$ we obtain $q=5/3$ which differs from the value $q=2$
corresponding to the $\gamma=2$ solutions available in the literature ($\nu<1$
porous medium equation), thus exhibiting nonuniform convergence.

</DOC>
<DOC>
<DOCNO> 10051 </DOCNO>
Dynamical pinning and non-Hermitian mode transmutation in the Burgers


  We discuss the mode spectrum in both the deterministic and noisy Burgers
equations in one dimension. Similar to recent investigations of vortex
depinning in superconductors, the spectrum is given by a non-Hermitian
eigenvalue problem which is related to a `quantum' problem by a complex gauge
transformation. The soliton profile in the Burgers equation serves as a complex
gauge field engendering a {\em mode transmutation} of diffusive modes into
propagating modes and giving rise to a {\em dynamical pinning} of localized
modes about the solitons.

</DOC>
<DOC>
<DOCNO> 9554 </DOCNO>
Links between gravity and dynamics of quantum liquids


  We consider the Landau-Khalatnikov two-fluid hydrodynamics of superfluid
liquid as an effective theory, which provides a self-consistent analog of
Einstein equations for gravity and matter.

</DOC>
<DOC>
<DOCNO> 169854 </DOCNO>
"Interaction-free" discrimination between semi-transparent objects


  Absorption-free (also known as ``interaction-free'') measurement aims to
detect the presence of an opaque object using a test particle without that
particle being absorbed by the object. Here we consider semi-transparent
objects which have an amplitude $\alpha$ of transmitting a particle while
leaving the state of the object unchanged and an amplitude $\beta$ of absorbing
the particle. The task is to devise a protocol that can decide which of two
known transmission amplitudes is present while ensuring that no particle
interacts with the object. We show that the probabilities of being able to
achieve this are limited by an inequality. This inequality implies that
absorption free distinction between complete transparency and any partial
transparency is always possible with probabilities approaching 1, but that two
partial transparencies can only be distinguished with probabilities less than
1.

</DOC>
<DOC>
<DOCNO> 102523 </DOCNO>
Random Walk in an Alcove of an Affine Weyl Group, and Non-Colliding


  We use a reflection argument, introduced by Gessel and Zeilberger, to count
the number of k-step walks between two points which stay within a chamber of a
Weyl group. We apply this technique to walks in the alcoves of the classical
affine Weyl groups. In all cases, we get determinant formulas for the number of
k-step walks. One important example is the region m>x_1>x_2>...>x_n>0, which is
a rescaled alcove of the affine Weyl group C_n. If each coordinate is
considered to be an independent particle, this models n non-colliding random
walks on the interval (0,m). Another case models n non-colliding random walks
on the circle.

</DOC>
<DOC>
<DOCNO> 120398 </DOCNO>
How accurately can we measure weak gravitational shear?


  With the recent detection of cosmic shear, the most challenging effect of
weak gravitational lensing has been observed. The main difficulties for this
detection were the need for a large amount of high quality data and the control
of systematics during the gravitational shear measurement process, in
particular those coming from the Point Spread Function anisotropy. In this
paper we perform detailed simulations with the state-of-the-art algorithm
developed by Kaiser, Squires and Broadhurst (KSB) to measure gravitational
shear. We show that for realistic PSF profiles the KSB algorithm can recover
any shear amplitude in the range $0.012 < |\gammavec |<0.32$ with a relative,
systematic error of $10-15%$. We give quantitative limits on the PSF correction
method as a function of shear strength, object size, signal-to-noise and PSF
anisotropy amplitude, and we provide an automatic procedure to get a reliable
object catalog for shear measurements out of the raw images.

</DOC>
<DOC>
<DOCNO> 12880 </DOCNO>
Effects of droplet fluctuations on the scattering of neutrons and light


  Beginning from the first neutron spin-echo study of the shape fluctuations of
microemulsion droplets [J.S. Huang, S.T. Milner, B. Farago, and D. Richter,
Phys. Rev. Lett. 59, 2600 (1987)] these experiments are incorrectly interpreted
in the literature. This is due to an inappropriate account for the fluctuations
and the erroneous application of the original theory to the experiments (see
[V. Lisy and B. Brutovsky, Czech. J. Phys. 50, 239 (2000)]). In the presented
work both these shortcomings are corrected. We develop the theory of static and
dynamic light and neutron scattering from droplet microemulsions. The fluids
inside and out of the droplets are separated by a surfactant layer of arbitrary
thickness. The scattering functions consistently take into account thermal
fluctuations of the shapes of such double-layered spheres to the second order
in the changes of their radius. The relaxation times and correlation functions
of the fluctuations are found within the Helfrich's theory of interfacial
elasticity. The theory is applied to the quantitative description of
small-angle neutron scattering, neutron spin-echo spectroscopy and dynamic
light scattering experiments. Basic characteristics of the microemulsions,
extracted from the fits to the experimental data, significantly differ from
those determined in the original works. We include into the consideration the
viscosity of the surface layer and give its estimation for the octane-C10E5-
water microemulsion.

</DOC>
<DOC>
<DOCNO> 12050 </DOCNO>
Configurational entropy and the one-step RSB scenario in glasses


  In this talk we discuss the possibility of constructing a fluctuation theory
for structural glasses in the non-equilibrium aging state. After reviewing well
known results in a toy model we discuss some of the key assumptions which
support the validity of this theory, in particular the role of the
configurational entropy and its relation to the effective temperature. Recent
numerical results for mean-field finite-size glasses agree with this scenario.

</DOC>
<DOC>
<DOCNO> 8819 </DOCNO>
Quantum Phase Diagram of the t-Jz Chain Model


  We present the quantum phase diagram of the one-dimensional $t$-$J_z$ model
for arbitrary spin (integer or half-integer) and sign of the spin-spin
interaction $J_z$, using an {\it exact} mapping to a spinless fermion model
that can be solved {\it exactly} using the Bethe ansatz. We discuss its
superconducting phase as a function of hole doping $\nu$. Motivated by the new
paradigm of high temperature superconductivity, the stripe phase, we also
consider the effect the antiferromagnetic background has on the $t$-$J_z$ chain
intended to mimic the stripe segments.

</DOC>
<DOC>
<DOCNO> 121810 </DOCNO>
A Polarization Flare in 3C 273: A Clue to Jet Physics


  We present UBVRIJHK polarization and flux density observations of the quasar
3C 273 obtained during a time of outburst over two weeks in 1988 February. We
have modelled these data with two power law components, each with
wavelength-independent position angle. These components are roughly
perpendicular. The steeper-spectrum component has higher infrared polarized
flux density, with the electric vector approximately transverse to the
projected direction of the VLBI jet. The K-band polarized flux density and
position angle, and possibly the spectral index of the two components, are
correlated with a time lag of less than a day. We explain our results in terms
of a shocked jet model with two nearly co-spatial components: a shock component
with magnetic field approximately perpendicular to the jet and the other with
magnetic field approximately parallel to the jet.

</DOC>
<DOC>
<DOCNO> 116819 </DOCNO>
Recent Advances in Electron and Positron Sources


  Recent advances in electron and positron sources have resulted in new
capabilities driven in most cases by the increasing demands of advanced
accelerating systems. Electron sources for brighter beams and for high
average-current beams are described. The status and remaining challenges for
polarized electron beams are also discussed. For positron sources, recent
activity in the development of polarized positron beams for future colliders is
reviewed. Finally, a new proposal for combining laser cooling with beam
polarization is presented.

</DOC>
<DOC>
<DOCNO> 151326 </DOCNO>
String theory as a universal language


  This article, based on the Klein lecture, contains some new results and new
speculations on various topics. They include discussion of open strings in the
AdS space, unusual features of D-branes, conformal gauge theories in higher
dimensions. We also comment on the infrared screening of the cosmological
constant and on the "brane worlds"

</DOC>
<DOC>
<DOCNO> 116830 </DOCNO>
Spatial coherence of thermal near fields


  We analyze the spatial coherence of the electromagnetic field emitted by a
half-space at temperature T close to the interface. An asymptotic analysis
allows to identify three different contributions to the cross-spectral density
tensor in the near-field regime. It is shown that the coherence length can be
either much larger or much shorter than the wavelength depending on the
dominant contribution.

</DOC>
<DOC>
<DOCNO> 71211 </DOCNO>
The Muon Anomalous Magnetic Moment: Standard Model Theory and Beyond


  QED, Hadronic, and Electroweak Standard Model contributions to the muon
anomalous magnetic moment, a_mu = (g_mu-2)/2, are reviewed. Theoretical
uncertainties in the prediction a_mu^SM = 116591597(67) times 10^{-11} are
scrutinized. Effects due to ``New Physics'' are described. Implications of the
current experiment vs. theory constraint a_mu^exp - a_mu^SM = 453(465) times
10^{-11} and anticipated near term error reduction to +- 155 times 10^{-11} are
discussed.

</DOC>
<DOC>
<DOCNO> 68312 </DOCNO>
Continuous emission versus freeze-out via HBT


  The effect of the continuous emission hypothesis on the two-pion
Bose-Einstein correlation function is discussed and compared with the
corresponding results based on the usual freeze-out. Sizeable differences in
the correlation function appear in these different descriptions of the
decoupling process. This means that, when extracting properties of the hot
matter formed in high-energy heavy-ion collisions from the data, completely
different conclusions may be reached according to the description of the
particle emission process adopted.

</DOC>
<DOC>
<DOCNO> 71085 </DOCNO>
Origin of the Nucleon Electromagnetic Form Factors Dipole Formula


  Starting with the VMD parametrization of the electric and magnetic nucleon
form factors, which are saturated just by the ground state vector-mesons rho,
omega and phi, then aplying the strict OZI rule and the asymptotic behaviour of
form factors as predicted by quark model of hadrons, the famous one parameter
dipole formula is derived. By its comparison with space-like data up to t = -5
GeV^2 the most optimal value of the parameter under consideration is
determined. Finaly, charge and magnetization distributions in proton and
neutron are predicted.

</DOC>
<DOC>
<DOCNO> 68413 </DOCNO>
On Symmetry of Elementary Particles


  The new quantum number \sigma is introduced. It is shown that the
conservation of \sigma-number results in the conservation of difference between
baryon and lepton numbers obtained earlier by Georgi and Glashow. The
conservation of \sigma -number also predicts that electron type neutrino mass
is exactly zero. The quark-lepton symmetry is discussed. It is shown that the
nature of quark-lepton symmetry is reflected by the fact that elementary
particles of the same generation are subject to the symmetry transformation
represented by 4-group of diedr. It is also shown that colorless elementary
particles are subject to the same symmetry transformation. The new elementary
particles (transbaryons) are predicted.

</DOC>
<DOC>
<DOCNO> 84457 </DOCNO>
Supersymmetry of topological Kerr-Newmann-Taub-NUT-aDS spacetimes


  We extend the topological Kerr-Newman-aDS solutions by including NUT charge
and find generalizations of the Robinson-Bertotti solution to the negative
cosmological constant case with different topologies. We show how all these
solutions can be obtained as limits of the general Plebanski-Demianski
solution. We study the supersymmetry properties of all these solutions in the
context of gauged N=2,d=4 supergravity. Generically they preserve at most 1/4
of the total supersymmetry. In the Plebanski-Demianski case, although gauged
N=2,d=4 supergravity does not have electric-magnetic duality, we find that the
family of supersymmetric solutions still enjoys a sort of electric-magnetic
duality in which electric and magnetic charges and mass and Taub-NUT charge are
rotated simultaneously.

</DOC>
<DOC>
<DOCNO> 69754 </DOCNO>
What if pulsars are born as strange stars?


  The possibility and the implications of the idea, that pulsars are born as
strange stars, are explored. Strange stars are very likely to have atmospheres
with typical mass of $\sim 5\times 10^{-15}M_\odot$ but bare polar caps almost
throughout their lifetimes, if they are produced during supernova explosions. A
direct consequence of the bare polar cap is that the binding energies of both
positively and negatively charged particles at the bare quark surface are
nearly infinity, so that the vacuum polar gap sparking scenario as proposed by
Ruderman & Sutherland should operate above the cap, regardless of the sense of
the magnetic pole with respect to the rotational pole. Heat can not accumulate
on the polar cap region due to the large thermal conductivity on the bare quark
surface. We test this ``bare polar cap strange star'' (BPCSS) idea with the
present broad band emission data of pulsars, and propose several possible
criteria to distinguish BPCSSs from neutron stars.

</DOC>
<DOC>
<DOCNO> 68542 </DOCNO>
Gaugino Mass Nonuniversality and Dark Matter in SUGRA, Strings and D


  The effects of nonuniversality of gaugino masses on dark matter are examined
within supersymmetric grand unification, and in string and D brane models with
R parity invariance. In SU(5) unified models nonuniversality in the gaugino
sector can be generated via the gauge kinetic energy function which may depend
on the 24, 75 and 200 dimensional Higgs representations. We also consider
string models which allow for nonuniversality of gaugino masses and D brane
models where nonuniversality arises from embeddings of the Standard Model gauge
group on five branes and nine branes. It is found that with gaugino mass
nonuniversality the range of the LSP mass can be extended much beyond the range
allowed in the universal SUGRA case, up to about 600 GeV even without
coannihilation effects in some regions of the parameter space. The effects of
coannihilation are not considered and inclusion of these effects may further
increase the allowed neutralino mass range. Similarly with the inclusion of
gaugino mass nonuniversality, the neutralino-proton ($\chi -p$) cross-section
can increase by as much as a factor of 10 in some of regions of the parameter
space. An analysis of the uncertainties in the quark density content of the
nucleon is given and their effects on $\chi -p$ cross-section are discussed.
The predictions of our analysis including nonuniversality is compared with the
current limits from dark matter detectors and implications for future dark
matter searches are discussed.

</DOC>
<DOC>
<DOCNO> 40458 </DOCNO>
A Renormalization Group Improved Calculation of Top Quark Production


  The top quark cross section close to threshold in $e^+e^-$ annihilation is
computed including the summation of logarithms of the velocity at
next-to-next-to-leading-logarithmic order in QCD. The remaining theoretical
uncertainty in the normalization of the total cross section is at the few
percent level, an order of magnitude smaller than in previous
next-to-next-to-leading order calculations. This uncertainty is smaller than
the effects of a light standard model Higgs boson.

</DOC>
<DOC>
<DOCNO> 170767 </DOCNO>
Nonlocal Effects of Partial Measurements and Quantum Erasure


  Partial measurement turns the initial superposition not into a definite
outcome but into a greater probability for it. The probability can approach
100%, yet the measurement can undergo complete quantum erasure. In the EPR
setting, we prove that i) every partial measurement nonlocally creates the same
partial change in the distant particle; and ii) every erasure inflicts the same
erasure on the distant particle's state. This enables an EPR experiment where
the nonlocal effect does not vanish after a single measurement but keeps
"traveling" back and forth between particles. We study an experiment in which
two distant particles are subjected to interferometry with a partial "which
path" measurement. Such a measurement causes a variable amount of correlation
between the particles. A new inequality is formulated for same-angle
polarizations, extending Bell's inequality for different angles. The resulting
nonlocality proof is highly visualizable, as it rests entirely on the
interference effect. Partial measurement also gives rise to a new form of
entanglement, where the particles manifest correlations of multiple
polarization directions. Another novelty in that the measurement to be erased
is fully observable, in contrast to prevailing erasure techniques where it can
never be observed. Some profound conceptual implications of our experiment are
briefly pointed out.

</DOC>
<DOC>
<DOCNO> 100632 </DOCNO>
The heat flow of the CCR algebra


  Let P and Q be the canonical operators acting on the Hilbert space of all L^2
functions on the real line, defined appropriately on a common dense domain. The
derivations D_P(A) = i(PA - AP) and D_Q(A) = i(QA - AQ) act on the *-algebra of
all integral operators having smooth kernels of compact support, for example,
and one may consider the noncommutative "Laplacian"
  L(A) = D_P^2(A) + D_Q^2(A), as a linear mapping of this *-algebra into
itself.
  L generates a semigroup of normal completely positive maps on B(H), and we
establish some basic properties of this semigroup and its minimal dilation to
an E_0-semigroup. In particular, we show that the minimal dilation is pure, has
no normal invariant states, and we discuss the significance of those facts for
the interaction theory developed in a previous paper (appearing in the current
issue of Comm. Math. Phys.).
  There are similar results for the canonical commutation relations with n
degrees of freedom, n = 2, 3, ....

</DOC>
<DOC>
<DOCNO> 119106 </DOCNO>
Theory of Microlensing


  I present a somewhat selective review of microlensing theory, covering five
major areas: 1) the derivation of the basic formulae, 2) the relation between
the observables and the fundamental physical parameters, 3) binaries, 4)
astrometric microlensing, and 5) femtolensing.

</DOC>
<DOC>
<DOCNO> 70561 </DOCNO>
About the structure of the Froissart limit in QCD


  The Froissart asymptotic behavior of cross-sections is usually considered in
a parton picture as corresponding to the collision of two almost black disks
filled with partons. In this article we mainly concentrate on the examination
of the local transparency of such F-disks. We discuss how is it possible to
guarantee the boost-invariance of the reciprocal transparency of two such
F-disks in a process of their collision, despite the fact that the mean area of
the overlapping of these F-disks at the same impact parameter is varying with
the Lorentz frame. We argue that on will always have such problems, if the
dominant interactions at all energies remain soft, but such a trouble can be
probably avoided if the mean parton virtualities grow with energies. This last
is natural in QCD, and we use the qualitative generalization of BFKL approach
to estimate the distribution of hard partons with various virtualities inside a
F-disk. As a result, the quasiclassical partonic wave function corresponding to
the F-limit can be approximately represented by the system of enclosed
parton-gluon disks with a growing virtuality and blackness. With the increase
of energy the new disks with larger virtualities are created in the middle of
the previous disks, and then they expand with the same transverse velocity.

</DOC>
<DOC>
<DOCNO> 9706 </DOCNO>
Universal free energy correction for the two-dimensional one-component


  The universal finite-size correction to the free energy of a two-dimensional
Coulomb system is checked in the special case of a one-component plasma on a
sphere. The correction is related to the known second moment of the short-range
part of the direct correlation function for a planar system.

</DOC>
<DOC>
<DOCNO> 10244 </DOCNO>
Giant Sommerfeld coefficient in the heavy-fermion YbBiPt


  It has been derived that the Sommerfeld coefficient $\gamma $ as large as 25
J/K$^2$mol can be theoretically accounted for provided the charge f-electron
fluctuations are substantially suppressed. This result enables the
understanding of the heavy-fermion YbBiPt ($\gamma $ =8 J/K$^2$mol) as the spin
fluctuator and should stimulate the experimental specific-heat research at low
temperatures.

</DOC>
<DOC>
<DOCNO> 152021 </DOCNO>
Brane inflation in tachyonic and non-tachyonic type 0B string theories


  We consider the motion of the brane universe moving in a background bulk
space of tachyonic and non-tachyonic type 0B string theory. The effective
densities are calculated for both cases and they show different power law
behavior. Brane inflation for non-tachyonic type 0B background has the same
power law behavior as that for type IIB background. The brane inflation under
tachyonic background is less divergent than the one without tachyon. The role
of tachyonic field in brane inflation scenario is different from that of the
ordinary matter field.

</DOC>
<DOC>
<DOCNO> 117061 </DOCNO>
Highlights of AAC 2000 Workshop


  The Advanced Accelerator Concepts 2000 (AAC2K) Workshop was held in Santa Fe
in June, 2000, and included a wide array of conceptual and theoretical advances
at the frontier of accelerator physics. This paper reviews the highlights of
the workshop, with subjects ranging from acceleration using lasers, plasmas and
microstructures, to the beam physics of muon colliders. Particular emphasis is
given to the topics which are relevant to research at existing linear
accelerator facilities, and the effect of this research on the capabilities of
such facilities.

</DOC>
<DOC>
<DOCNO> 7706 </DOCNO>
Decay on several sorts of heterogeneous centers: Special monodisperse


  The situation of the metastable phase decay on the several types of
heterogeneous centers is considered. This publication directly continues "
cond-mat@xxx.lanl.gov get 0001104 ". Here we give the results of numerical
modeling for the total monodisperse approximation. The numerical results for
the relative error of this approximation are presented. These results are
necessary to estimate from above the error of the special monodisperse
approximation.

</DOC>
<DOC>
<DOCNO> 101289 </DOCNO>
Full chains of twists for orthogonal algebras


  We show that for some Hopf subalgebras in U_F(so(M)) nontrivially deformed by
a twist F it is possible to find the nonlinear primitive copies. This enlarges
the possibilities to construct chains of twists. For orthogonal algebra
U(so(M)) we present a method to compose the full chains with carrier space as
large as the Borel subalgebra B(so(M)). These chains can be used to construct
the new deformed Yangians.

</DOC>
<DOC>
<DOCNO> 70446 </DOCNO>
Towards an understanding of isospin violation in pion-nucleon scattering


  We investigate isospin breaking in low-energy pion-nucleon scattering in the
framework of chiral perturbation theory. This work extends the systematic
analysis of [1] to the energy range above threshold. Various relations, which
identically vanish in the limit of isospin symmetry, are used to quantify
isospin breaking effects. We study the energy dependence of the S- and P-wave
projections of these ratios and find dramatic effects in the S-waves of those
two relations which are given in terms of isoscalar quantities only. This
effect drops rather quickly with growing center-of-mass energy.

</DOC>
<DOC>
<DOCNO> 71012 </DOCNO>
Long Range Forces from Quantum Field Theory at Zero and Finite


  We discuss the derivation of Newtonian potentials in the framework of quantum
field theory. We focus on two particular points: on long range forces i.e.
forces which fall off as $1/r^n$ being mediated by light quanta like neutrinos
or Goldstone bosons and on possible temperature dependence of such forces
arising in situations when the exchanged quanta are in a thermal heat bath.
Examples of the latter are cosmic relic photons and relic neutrinos. Among
other things, we will show that the existence of cosmic relic neutrinos
modifies the long tail of the two-neutrino exchange Feinberg-Sucher force
drastically. Results concerning the potential mediated by two Goldstone bosons
are also presented.

</DOC>
<DOC>
<DOCNO> 152073 </DOCNO>
Localized Gravitons, Gauge Bosons and Chiral Fermions in Smooth Spaces


  We study five-dimensional solutions to Einstein equations coupled to a scalar
field. Bounce-type solutions for the scalar field are associated with AdS_5
spaces with smooth warp functions. Gravitons are dynamically localized in this
framework in analogy to the Randall-Sundrum solution whereas, a bulk fermion
gives rise to a single chiral zero mode localized at the bounce. Additional
bulk scalar fields are incorporated in this picture. The dilaton, as a bulk
scalar leads, through its coupling, to localized gauge boson fields, something
that holds also in the case that the bounce system is replaced by a brane.

</DOC>
<DOC>
<DOCNO> 9443 </DOCNO>
Flow Between Two Sites on a Percolation Cluster


  We study the flow of fluid in porous media in dimensions $d=2$ and 3. The
medium is modeled by bond percolation on a lattice of $L^d$ sites, while the
flow front is modeled by tracer particles driven by a pressure difference
between two fixed sites (``wells'') separated by Euclidean distance $r$. We
investigate the distribution function of the shortest path connecting the two
sites, and propose a scaling {\it Ansatz} that accounts for the dependence of
this distribution (i) on the size of the system, $L$, and (ii) on the bond
occupancy probability, $p$. We confirm by extensive simulations that the {\it
Ansatz} holds for $d=2$ and 3, and calculate the relevant scaling parameters.
We also study two dynamical quantities: the minimal traveling time of a tracer
particle between the wells and the length of the path corresponding to the
minimal traveling time ``fastest path'', which is not identical to the shortest
path. A scaling {\it Ansatz} for these dynamical quantities also includes the
effect of finite system size $L$ and off-critical bond occupation probability
$p$. We find that the scaling form for the distribution functions for these
dynamical quantities for $d=2$ and 3 is similar to that for the shortest path
but with different critical exponents. The scaling form is represented as the
product of a power law and three exponential cutoff functions. We summarize our
results in a table which contains estimates for all parameters which
characterize the scaling form for the shortest path and the minimal traveling
time in 2 and 3 dimensions; these parameters are the fractal dimension, the
power law exponent, and the constants and exponents that characterize the
exponential cutoff functions.

</DOC>
<DOC>
<DOCNO> 8041 </DOCNO>
Dependence of the BEC transition temperature on interaction strength: a


  We compute the critical temperature T_c of a weakly interacting uniform Bose
gas in the canonical ensemble, extending the criterion of condensation provided
by the counting statistics for the uniform ideal gas. Using ordinary
perturbation theory, we find in first order $(T_c-T_c^0)/T_c^0 = -0.93
a\rho^{1/3}$, where T_c^0 is the transition temperature of the corresponding
ideal Bose gas, a is the scattering length, and $\rho$ is the particle number
density.

</DOC>
<DOC>
<DOCNO> 8635 </DOCNO>
Delocalization of two-particle ring near the Fermi level of 2d Anderson


  We study analytically and numerically the problem of two particles with a
long range attractive interaction on a two-dimensional (2d) lattice with
disorder. It is shown that below some critical disorder the interaction creates
delocalized coupled states near the Fermi level. These states appear inside
well localized noninteracting phase and have a form of two-particle ring which
diffusively propagates over the lattice.

</DOC>
<DOC>
<DOCNO> 102482 </DOCNO>
Cycles, submanifolds, and structures on normal bundles


  We give explicit examples of degree 3 cohomology classes not Poincare dual to
submanifolds, and discuss the realisability of homology classes by submanifolds
with Spin-C normal bundles.

</DOC>
<DOC>
<DOCNO> 117253 </DOCNO>
New access to very weak interactions in molecules


  It is predicted that nuclear spin conversion in molecules can be efficiently
controlled by strong laser radiation resonant to rovibrational molecular
transition. The phenomenon can be used for substantial enrichment of spin
isomers, or for detection of very weak (10-100 Hz) interactions in molecules.

</DOC>
<DOC>
<DOCNO> 178395 </DOCNO>
Spin-orbit interaction in Hartree-Fock calculations


  The contribution of the spin-orbit interaction in Hartree-Fock calculations
for closed shell nuclei is studied. We obtain explicit expressions for the
finite range spin-orbit force. New terms with respect to the traditional
spin-orbit expressions are found. The importance of the finite-range is
analyzed. Results obtained with spin-orbit terms taken from realistic
interactions are presented. The effect of the spin-orbit isospin dependent
terms is evaluated.

</DOC>
<DOC>
<DOCNO> 83454 </DOCNO>
Transformation-Based Bottom-Up Computation of the Well-Founded Model


  We present a framework for expressing bottom-up algorithms to compute the
well-founded model of non-disjunctive logic programs. Our method is based on
the notion of conditional facts and elementary program transformations studied
by Brass and Dix for disjunctive programs. However, even if we restrict their
framework to nondisjunctive programs, their residual program can grow to
exponential size, whereas for function-free programs our program remainder is
always polynomial in the size of the extensional database (EDB).
  We show that particular orderings of our transformations (we call them
strategies) correspond to well-known computational methods like the alternating
fixpoint approach, the well-founded magic sets method and the magic alternating
fixpoint procedure. However, due to the confluence of our calculi, we come up
with computations of the well-founded model that are provably better than these
methods.
  In contrast to other approaches, our transformation method treats magic set
transformed programs correctly, i.e. it always computes a relevant part of the
well-founded model of the original program.

</DOC>
<DOC>
<DOCNO> 13293 </DOCNO>
Energy-level correlations in chiral symmetric disordered systems:


  We investigate the deviation of the level-correlation functions from the
universal form for the chiral symmetric classes. Using the supersymmetric
nonlinear sigma model we formulate the perturbation theory. The large energy
behavior is compared with the result of the diagrammatic perturbation theory.
We have the diffuson and cooperon contributions even in the average density of
states. For the unitary and orthogonal classes we get the small energy behavior
that suggests a weakening of the level repulsion. For the symplectic case we
get a result with opposite tendency.

</DOC>
<DOC>
<DOCNO> 11488 </DOCNO>
Analytic verification of the droplet picture in the two-dimensional


  It is widely accepted that the free energy F(H) of the two-dimensional Ising
model in the ferromagnetic phase T<T_c has an essential branch cut singularity
at the origin H=0. The phenomenological droplet theory predicts that near the
cut drawn along the negative real axis H<0, the imaginary part of the free
energy per lattice site has the form Im F[exp (\pm i\pi |H|)] = \pm B |H| exp
(-A/|H|) for small |H|. We verify this prediction in analytical perturbative
transfer matrix calculations for the square lattice Ising model for all
temperatures 0<T<T_c and arbitrary anisotropy ratio J_1/J_2. We obtain an
expression for the constant A which coincides exactly with the prediction of
the droplet theory. For the amplitude B we obtain B =\pi M/18, where M is the
equilibrium spontaneous magnetization. In addition we find discrete-lattice
corrections to the above mentioned phenomenological formula for ImF, which
oscillate in H^{-1}.

</DOC>
<DOC>
<DOCNO> 69755 </DOCNO>
Vacuum and MSW interpretations of solar neutrino data with the LNW mass


  The Lehmann-Newton-Wu mass matrix, which was recently applied to neutrinos,
is further investigated. The analytic results presented earlier are confirmed
numerically for the solar density profile of the Standard Solar Model. The
combined analysis of atmospheric and solar neutrino data favors the MSW
solution over the vacuum-oscillation solution. The total rates from the solar
neutrino detectors and spectrum distortion reported by the Super-Kamiokande
collaboration for solar neutrinos favors one heavy (m3\sim 0.05 eV) and two
light (m1, m2\lsim 0.003 eV) neutrinos.

</DOC>
<DOC>
<DOCNO> 9700 </DOCNO>
Modelling of Stochastic Absorption in a Random Medium


  We report a detailed and systematic study of wave propagation through a
stochastic absorbing random medium. Stochastic absorption is modeled by
introducing an attenuation constant per unit length $\alpha$ in the free
propagation region of the one-dimensional disordered chain of delta function
scatterers. The average value of the logarithm of transmission coefficient
decreases linearly with the length of the sample. The localization length is
given by $\xi ~ = ~ \xi_w \xi_\alpha / (\xi_w + \xi_\alpha)$, where $\xi_w$ and
$\xi_\alpha$ are the localization lengths in the presence of only disorder and
of only absorption respectively. Absorption does not introduce any additional
reflection in the limit of large $\alpha$, i.e., reflection shows a monotonic
decrease with $\alpha$ and tends to zero in the limit of $\alpha\to\infty$, in
contrast to the behavior observed in case of coherent absorption. The
stationary distribution of reflection coefficient agrees well with the
analytical results obtained within random phase approximation (RPA) in a larger
parameter space. We also emphasize the major differences between the results of
stochastic and coherent absorption.

</DOC>
<DOC>
<DOCNO> 71820 </DOCNO>
Renormalizing DLCQ Using Supersymmetry


  Recent string theory developments suggest the necessity to understand
supersymmetric gauge theories non-perturbatively, in various dimensions. In
this work we show that there is a standard Hamiltonian formulation that
generates a finite and supersymmetric result at every order of the DLCQ
approximation scheme. We present this DLCQ renormalized Hamiltonian and solve
for the bound states and the wave functions to verify that it exactly
reproduces the large N SDLCQ results. We find that it has two novel features:
it automatically chooses the t'Hooft prescription for renormalizing the
singularities and it introduces irrelevant operators that serve to preserve the
supersymmetry and improve the convergence. This is a first step in extending
the advantages of SDLCQ to non-supersymmetric theories.

</DOC>
<DOC>
<DOCNO> 40587 </DOCNO>
Survey of present data on photon structure functions and resolved photon


  Present data on the partonic content of the photon from LEP, TRISTAN and HERA
accelerators are reviewed and the essential aspects of the underlying ideas and
methods are pointed out. Results of the unpolarized photon structure function
F_2 from DIS_{e gamma} experiments and on large p_T jet production processes in
the resolved gamma-gamma collisions are presented for both real and virtual
photons. The results of analysis of the hadronic final state accompanying the
DIS_{e gamma} measurements, showing some discrepancies with the Monte Carlo
models, are collected together and presented as a separate issue. Also results
on the DIS_{e gamma} with leptonic final states are shown. The results from
resolved real and virtual photon processes at HERA collider based on the single
and double jet events, also charged particles and prompt photons, are
presented. In the context of virtual photon processes the data for forward jet
and forward particle production are included. In addition a short presentation
of the recent data on the heavy quark content of the photon is given. Related
topics - the polarized (spin dependent) structure functions for the real and
virtual photon, the structure function of the electron and the photonic content
of the proton are also shortly mentioned.

</DOC>
<DOC>
<DOCNO> 85437 </DOCNO>
Wormholes and Spacetime Foam: an approach to the Cosmological Constant


  This paper summarizes the contribution presented at the IX Marcel Grossmann
Meeting (Rome, July 2000). A simple model of spacetime foam, made by $N$
Schwarzschild wormholes in a semiclassical approximation, is here proposed. The
Casimir-like energy of the quantum fluctuation of such a model and its
probability of being realized are computed. Implications on the
Bekenstein-Hawking entropy and the cosmological constant are considered. A
proposal for an alternative foamy model formed by $N$ Schwarzschild-Anti-de
Sitter wormholes is here considered.

</DOC>
<DOC>
<DOCNO> 14153 </DOCNO>
Charged Vortices in High Temperature Superconductors Probed by NMR


  We report a first experimental evidence that a vortex in the high temperature
superconductors (HTSC) traps a finite electric charge from the high resolution
measurements of the nuclear quadrupole frequencies. In slightly overdoped
YBa_2Cu_3O_7 the vortex is negatively charged by trapping electrons, while in
underdoped YBa_2Cu_4O_8 it is positively charged by expelling electrons. The
sign of the trapped charge is opposite to the sign predicted by the
conventional BCS theory. Moreover, in both materials, the deviation of the
magnitude of the charge from the theory is also significant. These unexpected
features can be attributed to the novel electronic structure of the vortex in
HTSC.

</DOC>
<DOC>
<DOCNO> 69991 </DOCNO>
Shadowing and Fragmentation in High-Energy Photo-Mesonproduction


  A model for the description of photonuclear reactions in the multi-GeV range
is described that combines the coherent initial state interactions (shadowing)
of the incoming photon with an incoherent coupled channel description of final
state interactons of outgoing particles. Particle production itself is treated
either, at low energies, through nucleon resonance decays or, at higher
energies, through string fragmentation. The initial state nucleons can be
far-off-shell due to ground state correlations. Results are shown for
semi-inclusive meson production.

</DOC>
<DOC>
<DOCNO> 71784 </DOCNO>
Direct Extraction of QCD Lambda MS-bar from e+e- Jet Observables


  We directly fit the QCD dimensional transmutation parameter, Lambda MS-bar,
to experimental data on e+e- jet observables, making use of next-to-leading
order (NLO) perturbative calculations. In this procedure there is no need to
mention, let alone to arbitrarily vary, the unphysical renormalisation scale
mu, and one avoids the spurious and meaningless ``theoretical error''
associated with standard alpha_s determinations. PETRA, SLD, and LEP data are
considered in the analysis. An attempt is made to estimate the importance of
uncalculated next-NLO and higher order perturbative corrections, and power
corrections, by studying the scatter in the values of Lambda MS-bar obtained
for different observables.

</DOC>
<DOC>
<DOCNO> 8736 </DOCNO>
Fluctuation Operators and Spontaneous Symmetry Breaking


  We develop an alternative approach to this field, which was to a large extent
developed by Verbeure et al. It is meant to complement their approach, which is
largely based on a non-commutative central limit theorem and coordinate space
estimates. In contrast to that we deal directly with the limits of $l$-point
truncated correlation functions and show that they typically vanish for $l\geq
3$ provided that the respective scaling exponents of the fluctuation
observables are appropriately chosen. This direct approach is greatly
simplified by the introduction of a smooth version of spatial averaging, which
has a much nicer scaling behavior and the systematic developement of Fourier
space and energy-momentum spectral methods. We both analyze the regime of
normal fluctuations, the various regimes of poor clustering and the case of
spontaneous symmetry breaking or Goldstone phenomenon.

</DOC>
<DOC>
<DOCNO> 119381 </DOCNO>
The STARE Project: A Transit Search for Hot Jupiters


  The STARE instrument is a small aperture, wide-field, CCD-based telescope
that delivers high cadence time series photometry on roughly 40,000 stars in a
typical field centered on the galactic plane. In a two-month observing run on a
field, we obtain sufficient precision on roughly 4,000 stars to detect a
close-in Jupiter-sized companion in an edge-on orbit. We also used this
instrument to detect the planetary transits across the Sun-like star HD209458.
The project is now in its third season, and we have acquired a large dataset on
several fields. Given the frequency of close-in extrasolar planets found by the
radial velocity surveys, and the recent confirmation that at least some of
these are indeed gas giants, the STARE project should be able to detect roughly
a dozen Jupiter-sized planets in its existing dataset.

</DOC>
<DOC>
<DOCNO> 69144 </DOCNO>
Flavor Gauge Bosons at the Tevatron


  We investigate collider signals for gauged flavor symmetries that have been
proposed in models of dynamical electroweak symmetry breaking and fermion mass
generation. We consider the limits on the masses of the gauge bosons in these
models which can be extracted from Tevatron Run I data in dijet production.
Estimates of the Run II search potential are provided. We show that the models
also give rise to significant signals in single top production which may be
visible at Run II. In particular we study chiral quark family symmetry and
SU(9) chiral flavor symmetry. The Run I limits on the gauge bosons in these
models lie between (1.5-2) TeV and should increase to about 3 TeV in Run II.
Finally, we show that an SU(12) enlargement of the SU(9) model, including
leptonic interactions, is constrained by low energy atomic parity violation
experiments to lie outside the reach of the Tevatron.

</DOC>
<DOC>
<DOCNO> 12307 </DOCNO>
Angle-Resolved Spectroscopy of Electron-Electron Scattering in a 2D


  Electron-beam propagation experiments have been used to determine the energy
and angle dependence of electron-electron (ee) scattering a two-dimensional
electron gas (2DEG) in a very direct manner by a new spectroscopy method. The
experimental results are in good agreement with recent theories and provide
direct evidence for the differences between ee-scattering in a 2DEG as compared
with 3D systems. Most conspicuous is the increased importance of small-angle
scattering in a 2D system, resulting in a reduced (but energy-dependent)
broadening of the electron beam.

</DOC>
<DOC>
<DOCNO> 13479 </DOCNO>
Domain Wall Resistance based on Landauer's Formula


  The scattering of the electron by a domain wall in a nano-wire is calculated
perturbatively to the lowest order. The resistance is calculated by use of
Landauer's formula. The result is shown to agree with the result of the linear
response theory if the equilibrium is assumed in the four-terminal case.

</DOC>
<DOC>
<DOCNO> 119766 </DOCNO>
Can EGRET's Gamma Ray Sources > 100 MeV Be Seen with Single Secondary


  The high energy gamma ray sources provided by experiment EGRET on the Compton
Gamma Ray Observatory are examined, testing Project GRAND's ability to detect
primary gamma rays by means of studying secondary muons. There is ~1.5% chance
that a 100 GeV primary cosmic gamma ray will produce a muon at detection level
(Fasso & Poirier, 1999), a probability which increases with increasing gamma
energy. Project GRAND has 80 square meters of muon detector which identifies
secondary muons >0.1 GeV and measures their angles to 0.26 deg (projected angle
in the XZ and YZ planes). Data taken during the last two years are analyzed. A
table of EGRET's gamma ray sources is examined (The Third EGRET Catalog of High
Energy Gamma Ray Sources (EGRET webpage, 1999). EGRET's flux (>0.1 GeV),
angular information, and spectral index were extrapolated to GRAND's energy
region (>30 GeV). Then the geometrical acceptance was calculated for each of
these events. Thus, GRAND's sensitivity to each of EGRET's sources was
predicted. A product of extrapolated flux and GRAND's detection sensitivity
yields an overall parameter indicating GRAND's relative sensitivity to each
source, assuming an energy dependence given by EGRET's spectral index. The 14
sources with the best extrapolated detection efficiency were selected to be
examined with the data.

</DOC>
<DOC>
<DOCNO> 100551 </DOCNO>
Local automorphisms of the unitary group and the general linear group on


  We prove that every 2-local automorphism of the unitary group or the general
linear group on a complex infinite-dimensional separable Hilbert space is an
automorphism. Thus these types of transformations are completely determined by
their local actions on the two-points subsets of the groups in question.

</DOC>
<DOC>
<DOCNO> 152418 </DOCNO>
Wilsonian Effective Actions and the IR/UV Mixing in Noncommutative Gauge


  Using background field perturbation theory we study Wilsonian effective
actions of noncommutative gauge theories with an arbitrary matter content. We
determine the Wilsonian coupling constant and the gauge boson polarization
tensor as functions of the momentum scale k at the one-loop level and study
their short-distance behaviour as theta k ->0, where theta is the
noncommutativity parameter. The mixing between the short-distance and the
long-distance degrees of freedom characteristic of noncommutative field
theories violates the universality of the Wilsonian action and leads to
IR-singularities. We find, in agreement with known results, that the quadratic
IR divergencies cancel in supersymmetric gauge theories. The logarithmic
divergencies disappear in mass-deformed N=4 theories, but not in other finite
N=2 theories. We next concentrate on finite N=2 and mass-deformed N=4
supersymmetric U(1) gauge theories with massive hypermultiplets. The Wilsonian
running coupling exhibits a non-trivial threshold behaviour at and well below
the noncomutativity scale, eventually becoming flat in the extreme infrared in
N=4 theories, but not in N=2 theories. This is interpreted as the
(non)-existence of a non-singular commutative limit where the theory is
described by a commutative N=2 pure U(1) theory. We expect that our analysis of
finite theories is exact to all orders in perturbation theory.

</DOC>
<DOC>
<DOCNO> 116352 </DOCNO>
On the Nature of Measurement in Quantum Mechanics


  A number of issues related to measurement show that self-consistency is
lacking in quantum mechanics as this theory has been generally understood. Each
issue is presented as a point in this paper. Each point can be resolved by
incorporating a cognitive component in quantum mechanics. Measurement in
quantum mechanics involves the meaning of the physical circumstances of the
experiment. This meaning is in part independent of what traditionally are
considered purely physical considerations.

</DOC>
<DOC>
<DOCNO> 70315 </DOCNO>
Azimuthal angular dependence of decay lepton in e+ e- --> t tbar


  We discuss top quark production and its subsequent decay for searching new
physics at lepton colliders. The angular dependence of the decay leptons is
calculated including both QCD corrections and anomalous gamma Z - t tbar
couplings. The off-diagonal spin basis for the top and anti-top quarks is shown
to be useful to probe the anomalous couplings.

</DOC>
<DOC>
<DOCNO> 11485 </DOCNO>
Andreev-reflection and Point-Contact Spectroscopy of Superconducting


  The superconducting energy gap and quasiparticle density of states (DOS) is
measured by means of Andreev-reflection spectroscopy in normal metal -
superconductor point contacts. It is found that both in paramagnetic and in
antiferromagnetically ordered states (Tm- and Dy-compounds) the DOS has the
BCS-like form while in Er- the dip in the temperature dependence of the gap is
observed at the Neel temperature. In Ho-compound, the non-BCS-like form of DOS
is observed in the temperature region where the incommensurate spin density
waves exist along the axes a and c .
   Inelastic point-contact spectroscopy performed on these compounds shows that
the low-frequency phonons are important for the superconducting state which are
strongly mixed with the magnetic excitation branches in magnetic
superconductors.

</DOC>
<DOC>
<DOCNO> 11958 </DOCNO>
Superfluidity in relativistic neutron stars


  The purpose of these notes is to give a brief review of superfluidity in
neutron stars. After a short presentation explaining why and how superfluidity
is expected in the crust and core of neutron stars, consequences on thermal
evolution and rotational dynamics are discussed. The second part summarizes a
formalism that has been recently developped to describe the hydrodynamics of
superfluids or superconductors in the framework of general relativity. As an
application, one can compute the oscillations of a two-component relativistic
neutron star.

</DOC>
<DOC>
<DOCNO> 70818 </DOCNO>
Electron Self Energy for the K and L Shell at Low Nuclear Charge


  A nonperturbative numerical evaluation of the one-photon electron self energy
for the K- and L-shell states of hydrogenlike ions with nuclear charge numbers
Z=1 to 5 is described. Our calculation for the 1S state has a numerical
uncertainty of 0.8 Hz in atomic hydrogen, and for the L-shell states (2S and
2P) the numerical uncertainty is 1.0 Hz. The method of evaluation for the
ground state and for the excited states is described in detail. The numerical
results are compared to results based on known terms in the expansion of the
self energy in powers of (Z alpha).

</DOC>
<DOC>
<DOCNO> 152478 </DOCNO>
The Heterotic Dyonic Instanton


  The static Yang-Mills-Higgs dyonic instanton is shown to have a
non-vanishing, but anti-self-dual, angular momentum 2-form with skew
eigenvalues equal to the electric charge; for large charge the angular momentum
causes the instanton to expand into a hyper-spherical shell. A class of exact
multi dyonic instantons is then found and then generalized to a new class of
1/4 supersymmetric, non-singular, stationary, exact solutions of the
ten-dimensional supergravity/Yang-Mills theory. These self-gravitating dyonic
instantons yield new heterotic string solitons, to leading order in the inverse
string tension.

</DOC>
<DOC>
<DOCNO> 101617 </DOCNO>
Magnification relations in gravitational lensing via multidimensional


  We investigate the so-called magnification relations of gravitational lensing
models. We show that multidimensional residue integrals provide a simple
explanation for the existence of these relations, and an effective method of
computation. We illustrate the method with several examples, thereby deriving
new magnification relations for galaxy lens models and microlensing (point mass
lensing).

</DOC>
<DOC>
<DOCNO> 150576 </DOCNO>
T Self-Dual Transverse Space and Gravity Trapping


  We advocate that the orbifold Z_2 symmetry of the gravity trapping model
proposed by Randall and Sundrum can be seen, in appropriate coordinates, as a
symmetry that exchanges the short distances with the large ones. Using
diffeomorphism invariance, we construct extensions defined by patch glued
together. A singularity occurs at the junction and it is interpreted as a
brane, the jump brane, of codimension one. We give explicit realization in ten
and eleven dimensional supergravity and show that the lower dimensional Planck
scale on the brane is finite. The standard model would be trapped on a
supersymmetric brane located at the origin whereas the jump brane would
surround it at a finite distance. The bulk interactions could transmit the
supersymmetry breaking from the jump brane to the SM brane.

</DOC>
<DOC>
<DOCNO> 71995 </DOCNO>
Probing chiral dynamics by charged-pion correlations


  The environment generated in the mid-rapidity region of a high-energy nuclear
collision endows the pionic degrees of freedom with a time-dependent effective
mass. Its specific evolution provides a mechanism for the production of
back-to-back charge-conjugate pairs of soft pions which may present an
observable signal of the non-equilibrium dynamics of the chiral order
parameter.

</DOC>
<DOC>
<DOCNO> 169757 </DOCNO>
Quantum mechanical probabilities and general probabilistic constraints


  Relativistic causality, namely, the impossibility of signaling at
superluminal speeds, restricts the kinds of correlations which can occur
between different parts of a composite physical system. Here we establish the
basic restrictions which relativistic causality imposes on the joint
probabilities involved in an experiment of the Einstein-Podolsky-Rosen-Bohm
type. Quantum mechanics, on the other hand, places further restrictions beyond
those required by general considerations like causality and consistency. We
illustrate this fact by considering the sum of correlations involved in the
CHSH inequality. Within the general framework of the CHSH inequality, we also
consider the nonlocality theorem derived by Hardy, and discuss the constraints
that relativistic causality, on the one hand, and quantum mechanics, on the
other hand, impose on it. Finally, we derive a simple inequality which can be
used to test quantum mechanics against general probabilistic theories.

</DOC>
<DOC>
<DOCNO> 150344 </DOCNO>
Discrete Torsion, AdS/CFT and duality


  We analyse D-branes on orbifolds with discrete torsion, extending earlier
results. We analyze certain Abelian orbifolds of the type C^3/ \Gamma, where
\Gamma is given by Z_m x Z_n, for the most general choice of discrete torsion
parameter. By comparing with the AdS/CFT correspondence, we can consider
different geometries which give rise to the same physics. This identifies new
mirror pairs and suggests new dualities at large N. As a by-product we also get
a more geometric picture of discrete torsion.

</DOC>
<DOC>
<DOCNO> 121282 </DOCNO>
Absorption line systems on the line of sight from SN 1987A to SN 1993J


  We present an extended analysis of the high dispersion IUE spectra of SN
1993J in M81, based on the improved data in the IUE final archive. Eight
interstellar absorption components can be identified in the velocity range from
-200 km/s to +200 km/s. Column densities are determined for Fe II, Mg I, Mg II,
O I, S II, Si II, and Zn II. From the ion ratios, we estimate electron
densities and temperatures of the gas in these components. In addition, we
rederive column density profiles for the higher ionisation stages Al III, Si
IV, and C IV for the entire line of sight.
  Of special interest are the absorption components at positive velocities,
which are associated with the intergalactic medium (IGM) in the foreground of
M81. The medium has many gas components, as known from radio measurements,
probably released in dynamical interactions by galaxies in the M81 group. The
IUE spectra contain the only UV absorption information on such gas. We find
neutral and ionised gas absorption at the same velocity, having a metal content
similar to a galactic disk.
  We combine the spectra towards SN 1993J in M81 with those towards SN 1987A in
the LMC, the directions being essentially antipodes on the celestical sphere.
Comparing the total profile with QSO spectra, we conclude that most absorption
in QSO spectra occurs in diffuse clouds on those sight lines and is not similar
to absorption by galactic disk gas. However, one absorption component towards
SN 1993J is clearly very similar to some of the absorption components in QSO
spectra.

</DOC>
<DOC>
<DOCNO> 40569 </DOCNO>
Top Production Properties at the Tevatron


  Following the confirmation of the top quark discovery at the Tevatron, the
next step is to begin studying its properties. Because the scale of electroweak
symmetry breaking is of the same order as the measured top mass, the top quark
may be very sensitive to new physics. We describe measurements of the total
top-antitop cross section, the top-antitop invariant mass, the top transverse
momentum distribution, and single top production from Run 1 data at D0 and CDF.
All of these measurements will become more precise in Run 2.

</DOC>
<DOC>
<DOCNO> 151999 </DOCNO>
Some Exact Results on Tachyon Condensation in String Field Theory


  The study of open string tachyon condensation in string field theory can be
drastically simplified by making an appropriate choice of coordinates on the
space of string fields. We show that a very natural coordinate system is
suggested by the connection between the worldsheet renormalization group and
spacetime physics. In this system only one field, the tachyon, condenses while
all other fields have vanishing expectation values. These coordinates are also
well-suited to the study of D-branes as solitons. We use them to show that the
tension of the D25-brane is cancelled by tachyon condensation and compute
exactly the profiles and tensions of lower dimensional D-branes.

</DOC>
<DOC>
<DOCNO> 120722 </DOCNO>
New Pulsars from an Arecibo Drift Scan Search


  We report the discovery of pulsars J0030+0451, J0711+0931, and J1313+0931
that were found in a search of 470 square degrees at 430 MHz using the 305m
Arecibo telescope. The search has an estimated sensitivity for long period, low
dispersion measure, low zenith angle, and high Galactic latitude pulsars of ~1
mJy, comparable to previous Arecibo searches. Spin and astrometric parameters
for the three pulsars are presented along with polarimetry at 430 MHz. PSR
J0030+0451, a nearby pulsar with a period of 4.8 ms, belongs to the less common
category of isolated millisecond pulsars. We have measured significant
polarization in PSR J0030+0451 over more than 50% of the period, and use these
data for a detailed discussion of its magnetospheric geometry. Scintillation
observations of PSR J0030+0451 provide an estimate of the plasma turbulence
level along the line of sight through the local interstellar medium.

</DOC>
<DOC>
<DOCNO> 67676 </DOCNO>
Dark Matter at the Galactic Center


  Particle dark matter near the galactic center is accreted by the central
black hole into a dense spike, strongly enhancing its annihilation rate.
Searching for its annihilation products may give us information on the presence
or absence of a central cusp in the dark halo profile. We summarize our paper
Phys Rev Lett 83, 1719 (1999), and use an updated limit on the neutrino
emission from the galactic center.

</DOC>
<DOC>
<DOCNO> 102344 </DOCNO>
Recursive Construction for a Class of Radial Functions I - Ordinary


  A class of spherical functions is studied which can be viewed as the matrix
generalization of Bessel functions. We derive a recursive structure for these
functions. We show that they are only special cases of more general radial
functions which also have a, properly generalized, recursive structure. Some
explicit results are worked out.

</DOC>
<DOC>
<DOCNO> 100620 </DOCNO>
Modelling of stock price changes: a real analysis approach


  The paper discusses a path-wise approach to stock price modelling.

</DOC>
<DOC>
<DOCNO> 9258 </DOCNO>
Optimizing Conflicts in the Formation of Strategic Alliances


  Coalition setting among a set of actors (countries, firms, individuals) is
studied using concepts from the theory of spin glasses. Given the distribution
of respective bilateral propensities to either cooperation or conflict, the
phenomenon of local aggregation is modeled. In particular the number of
coalitions is determined according to a minimum conflict principle. It is found
not to be always two. Along these lines, previous studies are revisited and are
found not to be consistent with their own principles. The model is then used to
describe the fragmentation of former Yugoslavia. Results are compared to the
actual situation.

</DOC>
<DOC>
<DOCNO> 101092 </DOCNO>
Witten deformed exterior derivative and Bessel functions


  In a recent paper we investigated the internal space of Bessel functions
associated with their orders. We found a formula (new) unifying Bessel
functions of integer and of real orders. In this paper we study the deformed
exterior derivative system $H=d_{\lambda}$ on the puctured plane as a tentative
to understand the origin of the formula and find that indeed similar formula
occurs. This is no coincidence as we will demonstrate that generating functions
of integer order Bessel functions and of real orders are respectively
eigenstates of the usual exterior derivative and its deformation. As a direct
consequence we rediscover the unifying formula and learn that the system linear
in $d_{\lambda}$ is related to Bessel theory much as the system quadratic in
($d_{\lambda}+d_{\lambda}^{*}$) is related to Morse theory.

</DOC>
<DOC>
<DOCNO> 69503 </DOCNO>
On the Nucleon Stability and Sigma_N Term Puzzles


  A stable soliton configuration for a nucleon emerges when the nucleon
stability and $\Sigma_N$ term discrepancy problems are studied
semi-quantitatively within a local theory developed recently. The approach
developed here goes beyond the mean field or Hartree-Fock approximation by
taking into account of the non-perturbative wave function renormalization in a
way that is consistent with the chiral Ward-Takahashi identities of QCD. The
stability condition for a nucleon and the recently extracted nucleon $\Sigma_N$
term are used to estimate the radius of the soliton. It is found that 0.67 fm
$\le R \le$ 0.78 fm. A new mechanism for the stability of a nucleon is
proposed. The discrepancy between the nucleon $\Sigma_N$ term extracted from
pion--nucleon scattering data and the one from baryonic spectra is resolved by
assuming the existence of a metastable virtual color superconducting phase for
the strong interaction vacuum. Under such a scenario, the difference between
the energy density of the chiral symmetry breaking phase and the metastable
color superconducting phase is found to be 0.41 GeV/fm$^3$ $\le
\Delta\epsilon\le $ 0.85 GeV/fm$^3$.

</DOC>
<DOC>
<DOCNO> 121137 </DOCNO>
A moving cold front in the intergalactic medium of A3667


  We present results from a Chandra observation of the central region of the
galaxy cluster A3667, with emphasis on the prominent sharp X-ray brightness
edge spanning 0.5 Mpc near the cluster core. Our temperature map shows
large-scale nonuniformities characteristic of the ongoing merger, in agreement
with earlier ASCA results. The brightness edge turns out to be a boundary of a
large cool gas cloud moving through the hot ambient gas, very similar to the
"cold fronts" discovered by Chandra in A2142. The higher quality of the A3667
data allows the direct determination of the cloud velocity. At the leading edge
of the cloud, the gas density abruptly increases by a factor of 3.9+-0.8, while
the temperature decreases by a factor of 1.9+-0.2 (from 7.7 keV to 4.1 keV).
The ratio of the gas pressures inside and outside the front shows that the
cloud moves through the ambient gas at near-sonic velocity, M=1+-0.2 or
v=1400+-300 km/s. In front of the cloud, we observe the compression of the
ambient gas with an amplitude expected for such a velocity. A smaller surface
brightness discontinuity is observed further ahead, ~350 kpc in front of the
cloud. We suggest that it corresponds to a weak bow shock, implying that the
cloud velocity may be slightly supersonic. Given all the evidence, the cold
front appears to delineate the remnant of a cool subcluster that recently has
merged with A3667. The cold front is remarkably sharp. The upper limit on its
width, 3.5 arcsec or 5 kpc, is several times smaller than the Coulomb mean free
path. This is a direct observation of suppression of the transport processes in
the intergalactic medium, most likely by magnetic fields.

</DOC>
<DOC>
<DOCNO> 101716 </DOCNO>
Occam's Razor as a Formal Basis for a Physical Theory


  We introduce the principle of Occam's Razor in a form which can be used as a
basis for economical formulations of physics.
 This allows us to explain the general structure of the Lagrangian for a
composite physical system, as well as some other artificial postulates behind
the variational formulations of physical laws.
 As an example, we derive Hamilton's principle of stationary action together
with the Lagrangians for the cases of Newtonian mechanics, relativistic
mechanics and a relativistic particle in an external gravitational field.

</DOC>
<DOC>
<DOCNO> 121013 </DOCNO>
Evolution of a Rotating Black Hole with a Magnetized Accretion Disk


  The effect of an accretion disk on the Blandford-Znajek process and the
evolution of a black hole are discussed using a simplified system for the black
hole - accretion disk in which the accretion rate is supposed to be dominated
by the strong magnetic field on the disk. The evolutions of the mass and the
angular momentum of the black hole are formulated and discussed with numerical
calculations.

</DOC>
<DOC>
<DOCNO> 11920 </DOCNO>
Percolation, Bose-Einstein Condensation, and String Proliferation


  The close analogy between cluster percolation and string proliferation in the
context of critical phenomena is studied. Like clusters in percolation theory,
closed strings, which can be either finite-temperature worldlines or
topological line defects, are described by a distribution parametrized by only
two exponents. On approaching the critical point, the string tension vanishes,
and the loops proliferate thereby signalling the onset of Bose-Einstein
condensation (in case of worldlines) or the disordering of the ordered state
(in case of vortices). The ideal Bose gas with modified energy spectrum is used
as a stepping stone to derive general expressions for the critical exponents in
terms of the two exponents parameterizing the loop distribution near
criticality.

</DOC>
<DOC>
<DOCNO> 11470 </DOCNO>
A lattice gas model of II-VI(001) semiconductor surfaces


  We introduce an anisotropic two-dimensional lattice gas model of metal
terminated II-IV(001) seminconductor surfaces. Important properties of this
class of materials are represented by effective NN and NNN interactions, which
result in the competition of two vacancy structures on the surface. We
demonstrate that the experimentally observed c(2x2)-(2x1) transition of the
CdTe(001) surface can be understood as a phase transition in thermal
equilbrium. The model is studied by means of transfer matrix and Monte Carlo
techniques. The analysis shows that the small energy difference of the
competing reconstructions determines to a large extent the nature of the
different phases. Possible implications for further experimental research are
discussed.

</DOC>
<DOC>
<DOCNO> 118234 </DOCNO>
Inflation and Eternal Inflation


  The basic workings of inflationary models are summarized, along with the
arguments that strongly suggest that our universe is the product of inflation.
The mechanisms that lead to eternal inflation in both new and chaotic models
are described. Although the infinity of pocket universes produced by eternal
inflation are unobservable, it is argued that eternal inflation has real
consequences in terms of the way that predictions are extracted from
theoretical models. The ambiguities in defining probabilities in eternally
inflating spacetimes are reviewed, with emphasis on the youngness paradox that
results from a synchronous gauge regularization technique. Vilenkin's proposal
for avoiding these problems is also discussed.

</DOC>
<DOC>
<DOCNO> 151121 </DOCNO>
Loop Transfer Matrix and Loop Quantum Mechanics


  We extend the previous construction of loop transfer matrix to the case of
nonzero self-intersection coupling constant $\kappa$. The loop generalization
of Fourier transformation allows to diagonalize transfer matrices depending on
symmetric difference of loops and express all eigenvalues of $3d$ loop transfer
matrix through the correlation functions of the corresponding 2d statistical
system. The loop Fourier transformation allows to carry out analogy with
quantum mechanics of point particles, to introduce conjugate loop momentum P
and to define loop quantum mechanics. We also consider transfer matrix on $4d$
lattice which describes propagation of memebranes. This transfer matrix can
also be diagonalized by using generalized Fourier transformation, and all its
eigenvalues are equal to the correlation functions of the corresponding $3d$
statistical system.

</DOC>
<DOC>
<DOCNO> 13441 </DOCNO>
Reducing nonideal to ideal coupling in random matrix description of


  We write explicitly a transformation of the scattering phases reducing the
problem of quantum chaotic scattering for systems with M statistically
equivalent channels at nonideal coupling to that for ideal coupling. Unfolding
the phases by their local density leads to universality of their local
fluctuations for large M. A relation between the partial time delays and
diagonal matrix elements of the Wigner-Smith matrix is revealed for ideal
coupling. This helped us in deriving the joint probability distribution of
partial time delays and the distribution of the Wigner time delay.

</DOC>
<DOC>
<DOCNO> 85378 </DOCNO>
Transplantation of Local Nets and Geometric Modular Action on


  A novel method of transplanting algebras of observables from de Sitter space
to a large class of Robertson-Walker space-times is exhibited. It allows one to
establish the existence of an abundance of local nets on these spaces which
comply with a recently proposed condition of geometric modular action. The
corresponding modular symmetry groups appearing in these examples also satisfy
a condition of modular stability, which has been suggested as a substitute for
the requirement of positivity of the energy in Minkowski space. Moreover, they
exemplify the conjecture that the modular symmetry groups are generically
larger than the isometry and conformal groups of the underlying space-times.

</DOC>
<DOC>
<DOCNO> 117443 </DOCNO>
Evolution of the cosmological density distribution function


  We present a new calculation for the evolution of the 1-point Probability
Distribution Function (PDF) of the cosmological density field based on an exact
statistical treatment. Using the Chapman-Kolmogorov equation and second-order
Eulerian perturbation theory we propagate the initial density distribution into
the nonlinear regime. Our calculations yield the moment generating function,
allowing a straightforward derivation of the skewness of the PDF to second
order. We find a new dependency on the initial perturbation spectrum. We
compare our results with other approximations to the 1-pt PDF, and with N-body
simulations. We find that our distribution accurately models the evolution of
the 1-pt PDF of dark matter.

</DOC>
<DOC>
<DOCNO> 11527 </DOCNO>
Calculation of thermodynamic properties of finite Bose-Einstein systems


  We derive an exact recursion formula for the calculation of thermodynamic
functions of finite systems obeying Bose-Einstein statistics. The formula is
applicable for canonical systems where the particles can be treated as
noninteracting in some approximation, e.g. like Bose-Einstein condensates in
magnetic traps. The numerical effort of our computation scheme grows only
linear with the number of particles. As an example we calculate the relative
ground state fluctuations and specific heats for ideal Bose gases with a finite
numbers of particles enclosed in containers of different shapes.

</DOC>
<DOC>
<DOCNO> 84528 </DOCNO>
Born-Infeld Cosmologies


  We present a model for an inhomogeneous and anisotropic early universe filled
with a nonlinear electromagnetic field of Born-Infeld (BI) type. The effects of
the BI field are compared with the linear case (Maxwell). Since the curvature
invaria nts are well behaved then we conjecture that our model does not present
an initial big bang singularity. The existence of the BI field modifies the
curvature invariants at t=0 as well as sets bounds on the amplitude of the
conformal metric function

</DOC>
<DOC>
<DOCNO> 151748 </DOCNO>
Holonomies, anomalies and the Fefferman-Graham ambiguity in AdS3 gravity


  Using the Chern-Simon formulation of (2+1) gravity, we derive, for the
general asymptotic metrics given by the Fefferman-Graham-Lee theorems, the
emergence of the Liouville mode associated to the boundary degrees of freedom
of (2+1) dimensional anti de Sitter geometries. Holonomies are described
through multi-valued gauge and Liouville fields and are found to algebraically
couple the fields defined on the disconnected components of spatial infinity.
In the case of flat boundary metrics, explicit expressions are obtained for the
fields and holonomies. We also show the link between the variation under
diffeomorphisms of the Einstein theory of gravitation and the Weyl anomaly of
the conformal theory at infinity.

</DOC>
<DOC>
<DOCNO> 151288 </DOCNO>
Gravitational Couplings for Generalized Orientifold Planes


  The Wess-Zumino action for generalized orientifold planes (GOp-planes) is
presented and a series power expantion is realized from which processes that
involves GOp-planes, RR-forms, gravitons and gaugeons, are obtained. Finally
non-standard GOp-planes are showed.

</DOC>
<DOC>
<DOCNO> 102013 </DOCNO>
A new A_n extension of Ramanujan's 1-psi-1 summation with applications


  In this article, we derive some identities for multilateral basic
hypergeometric series associated to the root system A_n. First, we apply
Ismail's argument to an A_n q-binomial theorem of Milne and derive a new A_n
generalization of Ramanujan's 1-psi-1 summation theorem. From this new A_n
1-psi-1 summation and from an A_n 1-psi-1 summation of Gustafson we deduce two
lemmas for deriving simple A_n generalizations of bilateral basic
hypergeometric series identities. These lemmas are closely related to the
Macdonald identities for A_n. As samples for possible applications of these
lemmas, we provide several A_n extensions of Bailey's 2-psi-2 transformations,
and several A_n extensions of a particular 2-psi-2 summation.

</DOC>
<DOC>
<DOCNO> 14010 </DOCNO>
Boundary conditions in the envelope function approximation as applied to


  We have found the equations that determine the self-adjoint extensions, and
thus the boundary conditions, of the differential operator used in the
multi-band k.p-theory, when the coefficients in the Kane-matrix are piecewise
constant. Both the one-dimensional and the three-dimensional case have been
investigated. A numerical calculation shows that the choice of boundary
conditions affects the energy eigenvalues for a quantum well.

</DOC>
<DOC>
<DOCNO> 13019 </DOCNO>
Ginsparg-Wilson relation with R=(a \gamma_5 D)^{2k}


  The Ginsparg-Wilson relation $D \gamma_5 + \gamma_5 D = 2 a D R \gamma_5 D$
with $R = (a \gamma_5 D)^{2k}$ is discussed. An explicit realization of D is
constructed. It is shown that this sequence of topologically-proper lattice
Dirac operators tend to a nonlocal operator in the limit $k \to \infty$. This
suggests that the locality of a lattice Dirac operator is irrelevant to its
index.

</DOC>
<DOC>
<DOCNO> 169719 </DOCNO>
Operator monotones, the reduction criterion and the relative entropy


  We introduce the theory of operator monotone functions and employ it to
derive a new inequality relating the quantum relative entropy and the quantum
conditional entropy. We present applications of this new inequality and in
particular we prove a new lower bound on the relative entropy of entanglement
and other properties of entanglement measures.

</DOC>
<DOC>
<DOCNO> 8141 </DOCNO>
First-principles calculations of hot-electron lifetimes in metals


  First-principles calculations of the inelastic lifetime of low-energy
electrons in Al, Mg, Be, and Cu are reported. Quasiparticle damping rates are
evaluated from the knowledge of the electron self-energy, which we compute
within the GW approximation of many-body theory. Inelastic lifetimes are then
obtained along various directions of the electron wave vector, with full
inclusion of the band structure of the solid. Average lifetimes are also
reported, as a function of the electron energy. In Al and Mg, splitting of the
band structure over the Fermi level yields electron lifetimes that are smaller
than those of electrons in a free-electron gas. Larger lifetimes are found in
Be, as a result of the characteristic dip that this material presents in the
density of states near the Fermi level. In Cu, a major contribution from $d$
electrons participating in the screening of electron-electron interactions
yields electron lifetimes which are well above those of electrons in a
free-electron gas with the electron density equal to that of valence ($4s^1$)
electrons.

</DOC>
<DOC>
<DOCNO> 71281 </DOCNO>
Brane World Linearized Cosmic String Gravity


  The gravitational properties of cosmic strings in the Randall-Sundrum brane
world scenario are investigated. Using a gauge in which the brane remains
straight, the leading order corrections to the metric on the brane are
determined. In contrast to their non-brane equivalents, these strings have an
attractive 1/r^2 potential and a radially dependent deficit angle. These two
effects alter many cosmological properties of the string, such as the formation
of double images. As a result of the attractive force the string will collect
matter as it moves through space.

</DOC>
<DOC>
<DOCNO> 116251 </DOCNO>
3-D extent of the main ionospheric trough--a case study


  The EISCAT radar system has been used for the first time in a four-beam
meridional mode. The FAST satellite and ALIS imaging system is used in
conjunction to support the radar data, which was used to identify a main
ionospheric trough. With this large latitude coverage the trough was passed in
2.5 hours period. Its 3-dimensional structure is investigated and discussed. It
is found that the shape is curved along the auroral oval, and that the trough
is wider closer to the midnight sector. The position of the trough coincide
rather well with various statistical models and this trough is found to be a
typical one.

</DOC>
<DOC>
<DOCNO> 10737 </DOCNO>
Memory in aged granular media


  Stimulated by recent experimental results, we simulate
``temperature''-cycling experiments in a model for the compaction of granular
media. We report on the existence of two types of memory effects: short-term
dependence on the history of the sample, and long-term memory for highly
compact (aged) systems. A natural interpretation of these results is provided
by the analysis of the density heterogeneities.

</DOC>
<DOC>
<DOCNO> 71723 </DOCNO>
On the Hypernuclear Weak Decay Puzzle


  A novel method for the evaluation of hypernuclear non-mesonic (NM) decay
rates is developed. The standard strangeness-changing weak $\Lambda N\to NN$
transition potential, involving the exchange of the complete
pseudoscalar-vector meson-octet ($\pi,\eta,K,\rho,\omega,K^*$), is used. The
corresponding non-relativistic approximation is critically revised, both in
momentum and in coordinate spaces. In this way are deduced some specially
important parity violating transition operators in the vector-meson exchanges,
which have been systematically omitted in the literature. With the commonly
used parametrization, for the one-meson-exchange model (OMEM), the calculated
rate $\Gamma_{NM}= \Gamma_n+\Gamma_p$ is of the order of the free $\Lambda$
decay rate $ \Gamma^0$($\Gamma_{NM}^{th}\cong \Gamma^0$), as is the
experimental one. Yet, neither the measurements for the ratio
$\Gamma_{n/p}=\Gamma_n/\Gamma_p$, nor that for $\Gamma_p$, are well accounted
for by the theory ($\Gamma_{n/p}^{th}\le 0.4; \Gamma_p^{th}\ge 0.8 \Gamma^0$).
By varying the OMEM parameters, it is possible to make agree the ${n/p}$ ratio
with the data ($\Gamma_{n/p}^{th}\cong 1$). The proton induced decay, however,
cannot be reconciled with measurements in this way ($\Gamma_p^{th}\ge 0.5
\Gamma^0$).

</DOC>
<DOC>
<DOCNO> 121954 </DOCNO>
The first XMM-Newton spectrum of a high redshift quasar - PKS 0537-286


  We present XMM-Newton observations of the high redshift z=3.104, radio-loud
quasar PKS 0537-286. The EPIC CCD cameras provide the highest signal-to-noise
spectrum of a high-z quasar to date. The EPIC observations show that PKS
0537-286 is extremely X-ray luminous (Lx=2x10^47 erg/s), with an unusually hard
X-ray spectrum (Gamma=1.27+/-0.02). The flat power-law emission extends over
the whole observed energy range; there is no evidence of intrinsic absorption,
which has been claimed in PKS 0537-286 and other high z quasars.
  However, there is evidence for weak Compton reflection. A redshifted iron K
line, observed at 1.5 keV - corresponding to 6.15 keV in the quasar rest frame
- is detected at 95% confidence. If confirmed, this is the most distant iron K
line known. The line equivalent width is small (33eV), consistent with the
`X-ray Baldwin effect' observed in other luminous quasars. The reflected
continuum is also weak (R=0.25). We find the overall spectral energy
distribution of PKS 0537-286 is dominated by the X-ray emission, which,
together with the flat power-law and weak reflection features, suggests that
the X-radiation from PKS 0537-286 is dominated by inverse Compton emission
associated with a face-on relativistic jet.

</DOC>
<DOC>
<DOCNO> 120577 </DOCNO>
Newtonian hydrodynamics of the coalescence of black holes with neutron


  We present a hydrodynamical study of the final stages of inspiral in a black
hole-neutron star (NS) binary. We use a Newtonian 3D SPH code, and model the NS
with a stiff (index G=3 and G=2.5) polytropic equation of state and the black
hole as a Newtonian point mass. Our initial conditions correspond to
irrotational binaries in equilibrium (approximating the NS as a compressible
ellipsoid), and we have explored configurations with different initial mass
ratios, 0.2< q=M_ns/M_bh<0.5. The dynamical evolution is followed for ~23ms. We
include gravitational radiation losses in the quadrupole approximation for a
point-mass binary. For G=3, after an initial episode of mass transfer, the NS
is not completely disrupted and a remnant core remains in orbit about the black
hole. For G=2.5 the disruption is more complex, with the NS being totally
disrupted during a second periastron passage. The accretion disc formed around
the black hole contains ~0.2 solar masses. A nearly baryon-free axis is always
present in the system, and only modest beaming of a relativistic fireball that
could give rise to a GRB would be sufficient to avoid baryon contamination.
Around 0.01 solar masses may be dynamically ejected from the system, and could
contribute substantially to the amount of observed galactic r-process material.
We calculate the gravitational radiation waveforms in the quadrupole
approximation. We also present the results of simulations that have used
spherical NSs relaxed in isolation as initial conditions, in order to gauge the
effect of using non-equilibrium initial conditions on the coalescence.

</DOC>
<DOC>
<DOCNO> 69440 </DOCNO>
Electromagnetic Pion and Nucleon Form Factors at Positive and Negative


  The electromagnetic form factors of pion and nucleon are considered within
the framework of the Quark-Gluon Strings Model, where the dependence of the
form factors on $q^2$ is determined by the intercept of a dominant Regge
trajectory and Sudakov form factor. The analytical expressions for the form
factors found in the time-like region can be directly continued to the
space-like region. Good agreement with available experimental data on the pion
and magnetic nucleon form factor is obtained at positive as well as negative
$q^2$. It is shown that the difference in $F_\pi$ and $G_m$ at positive and
negative values of $q^2$ is mainly related to the behavior of the double
logarithmic term in the exponent of Sudakov form factor. The model describes
also existing data on the Pauli nucleon form factor $F_2$ and the ratio
$G_e/G_m$.

</DOC>
<DOC>
<DOCNO> 101063 </DOCNO>
Is Schroedinger equation consistent with information theory?


  It is shown that Schroedinger equation is not consistent with information
theory. From the modified form of information which ensures that the most
probable density function it yields tallies with a general form of continuous
Riemann integrable density function that has real or imaginary zeros or
singularities at end points of $[a,b] \epsilon R$, a new variational
formulation for quantum mechanics is proposed that yields a system of
Euler-Lagrange equations that are non-linear. It is proved that the solutions
of this system are unique, orthonormal and complete. One dimensional harmonic
oscillator has been solved.

</DOC>
<DOC>
<DOCNO> 150484 </DOCNO>
A Generalization of the Submodel of Nonlinear CP^1 Models


  We generalize the submodel of nonlinear CP^1 models. The generalized models
include higher order derivatives. For the systems of higher order equations, we
construct a B\"acklund-like transformation of solutions and an infinite number
of conserved currents by using the Bell polynomials.

</DOC>
<DOC>
<DOCNO> 119095 </DOCNO>
The Three-dimensional Evolution of Rising, Twisted Magnetic Flux Tubes


  We present three-dimensional numerical simulations of the rise and
fragmentation of twisted, initially horizontal magnetic flux tubes which evolve
into emerging Omega-loops. The flux tubes rise buoyantly through an
adiabatically stratified plasma that represents the solar convection zone. The
MHD equations are solved in the anelastic approximation, and the results are
compared with studies of flux tube fragmentation in two dimensions. We find
that if the initial amount of field line twist is below a critical value, the
degree of fragmentation at the apex of a rising Omega-loop depends on its
three-dimensional geometry: the greater the apex curvature of a given
Omega-loop, the lesser the degree of fragmentation of the loop as it approaches
the photosphere. Thus, the amount of initial twist necessary for the loop to
retain its cohesion can be reduced substantially from the two-dimensional
limit. The simulations also suggest that as a fragmented flux tube emerges
through a relatively quiet portion of the solar disk, extended crescent-shaped
magnetic features of opposite polarity should form and steadily recede from one
another. These features eventually coalesce after the fragmented portion of the
Omega-loop emerges through the photosphere.

</DOC>
<DOC>
<DOCNO> 151913 </DOCNO>
D-branes, Discrete Torsion and the McKay Correspondence


  We analyze the D-branes of a type IIB string theory on an orbifold
singularity including the possibility of discrete torsion following the work of
Douglas et al. First we prove some general results about the moduli space of a
point associated to the "regular representation" of the orbifold group. This
includes some analysis of the "wrapped branes" which necessarily appear when
the orbifold singularity is not isolated. Next we analyze the stringy homology
of the orbifold using the McKay correspondence and the relationship between
K-theory and homology. We find that discrete torsion and torsion in this
stringy homology are closely-related concepts but that they differ in general.
Lastly we question to what extent the D-1 brane may be thought of as being dual
to a string.

</DOC>
<DOC>
<DOCNO> 12827 </DOCNO>
Surface Tension of a Metal-Electrolyte Boundary: Exactly Solvable Model


  An ideal conductor electrode in contact with a semi-infinite two-dimensional
two-component plasma in an external potential is considered. The model is
mapped onto an integrable sine-Gordon theory with Dirichlet boundary
conditions. The information gained from the mapping provides an explicit form
of the surface tension in the plasma-stability regime.

</DOC>
<DOC>
<DOCNO> 10691 </DOCNO>
Issues, Concepts, and Challenges in Spintronics


  We review from a theoretical perspective the emerging field of spintronics
where active control of spin transport and dynamics in electronic materials may
provide novel device application possibilities. In particular, we discuss the
quantum mechanical principles underlying spintronics applications, emphasizing
the formidable challenges involving spin decoherence and spin injection facing
any eventual device fabrication. We provide a critical assessment of the
current status of the field with special attention to possible device
applications.

</DOC>
<DOC>
<DOCNO> 10200 </DOCNO>
Dispersion and Symmetry of Bound States in the Shastry-Sutherland Model


  Bound states made from two triplet excitations on the Shastry-Sutherland
(ShaSu) lattice are investigated. Based on the perturbative unitary
transformation by flow equations quantitative properties like dispersions and
qualitative properties like symmetries are determined. The high order results
(up to (J_2/J_1)^{14}) permit to fix the parameters of SrCu_2(BO_3)_2
precisely: J_1=6.16(10)meV, x:=J_2/J_1=0.603(3), J_\perp=1.3(2)meV. At the
border of the magnetic Brillouin zone (MBZ) a general double degeneracy is
derived. An unexpected instability in the triplet channel at x=0.63 indicates a
first order transition towards a triplet condensate, related to classical
helical order.

</DOC>
<DOC>
<DOCNO> 70296 </DOCNO>
$B^0_{d,s}\to \mu^-\mu^+$ in the MSSM


  We present the results of the complete one-loop computation of the
$B^0_{d,s}\to l^+l^-$ decay rate in the MSSM. Both sources of the FCNC, the CKM
matrix and off-diagonal entries of the sfermion mass matrices are considered.
Strong enhancement of the branching ratio (compared to the SM prediction) can
be obtained in the large $\tan\beta\sim m_t/m_b$ regime in which the neutral
Higgs boson ``penguin'' diagrams dominate. We make explicit the strong
dependence of this enhancement on the top squarks mixing angle in the case of
the chargino contribution and on the $\mu$ parameter in the case of the gluino
contribution. We show that, in some regions of the MSSM parametre space, the
branching ratio for this process can be as large as $10^{-(5-4)}$ respecting
all existing constraints, including the CLEO measurement of $BR(B\to
X_s\gamma)$. We also estimate, that for chargino and stop masses $\sim{\cal
O}(100$ GeV) $BR(B^0_s\to l^+l^{\prime -})$ with $ll^\prime=e\tau$ or $\mu\tau$
can be of the order of $10^{-11}$ for the still allowed values of the
off-diagonal entries in the slepton mass matrix.

</DOC>
<DOC>
<DOCNO> 39936 </DOCNO>
16-N as a calibration source for Super-Kamiokande


  The decay of 16-N is used to cross check the absolute energy scale
calibration for solar neutrinos established by the electron linear accelerator
(LINAC). A deuterium-tritium neutron generator was employed to create 16-N via
the (n,p) reaction on 16-O in the water of the detector. This technique is
isotropic and has different systematic uncertainties than the LINAC. The
results from this high statistics data sample agree with the absolute energy
scale of the LINAC to better than 1%. A natural source of 16-N from the capture
of mu^- on 16-O, which is collected as a background to the solar neutrino
analysis, is also discussed.

</DOC>
<DOC>
<DOCNO> 120184 </DOCNO>
An attempt to do without dark matter


  The discrepancy between dynamical mass measures of objects such as galaxies
and the observed distribution of luminous matter in the universe is typically
explained by invoking an unseen ``dark matter'' component. Dark matter must
necessarily be non-baryonic. We introduce a simple hypothesis to do away with
the necessity for dark matter by introducing an additional non-gravitational
force coupled to baryon number as a charge. We compare this hypothesis to
Milgrom's Modified Newtonian Dynamics. The model ultimately fails when
confronted with observation, but it fails in an interesting way.

</DOC>
<DOC>
<DOCNO> 118068 </DOCNO>
The Detection of Multimodal Oscillations on Alpha UMa


  We have used the star camera on the WIRE satellite to observe the K0 III star
Alpha UMa, and we report the apparent detection of 10 oscillation modes. The
lowest frequency mode is at 1.82 microhertz, and appears to be the fundamental
mode. The mean spacing between the mode frequencies is 2.94 microhertz, which
implies that all detected modes are radial. The mode frequencies are consistent
with the physical parameters of a K0 III star, if we assume that only radial
modes are excited. Mode amplitudes are 100 -- 400 micromagnitudes, which is
consistent with the scaling relation of Kjeldsen & Beddinge (1995).

</DOC>
<DOC>
<DOCNO> 67795 </DOCNO>
Low Energy Hadron Physics


  Ask a group of particle theorists about low energy hadron physics and they
will say that this is a subject that belongs to the age of the dinosaurs.
 However, it is GeV physics that controls the outcome of every hadronic
interaction at almost every energy. Confinement of quarks and gluons (and any
other super-constituents) means that it is the femto-universe that determines
what experiments detect.
 What we have to learn at the start of the 21st century is discussed.

</DOC>
<DOC>
<DOCNO> 151001 </DOCNO>
A Realization of the infinite dimensional Symmetries of Conformal


  We discuss the possibility of realizing the infinite dimensional symmetries
of conformal mechanics as time reparametrizations, generalizing the realization
of the SL(2,R) symmetry of the de Alfaro, Fubini, Furlan model in terms of
quasi--primary fields. We find that this is possible using an appropriate
generalization of the transformation law for the quasi-primary fields.

</DOC>
<DOC>
<DOCNO> 120822 </DOCNO>
Triaxial Haloes and Particle Dark Matter Detection


  This paper presents the properties of a family of scale-free triaxial haloes.
We adduce arguments to suggest that the velocity ellipsoids of such models are
aligned in conical coordinates. We provide an algorithm to find the set of
conically aligned velocity second moments that support a given density against
the gravity field of the halo. The case of the logarithmic ellipsoidal model --
the simplest triaxial generalisation of the familiar isothermal sphere -- is
examined in detail. The velocity dispersions required to hold up the
self-consistent model are analytic. The velocity distribution of the dark
matter can be approximated as a triaxial Gaussian with semiaxes equal to the
velocity dispersions. There are roughly twenty experiments worldwide that are
searching for evidence of scarce interactions between weakly-interacting
massive-particle dark matter (WIMPs) and detector nuclei. The annual modulation
signal, caused by the Earth's rotation around the Sun, is a crucial
discriminant between WIMP events and the background. The greatest rate is in
June, the least in December. We compute the differential detection rate for
energy deposited by the rare WIMP-nucleus interactions in our logarithmic
ellipsoidal halo models. Triaxiality and velocity anisotropy change the total
rate by up to 40 %, and have a substantial effect on the amplitude of the
annual modulation signal. The overall rate is greatest, but the amplitude of
the modulation is weakest, in our radially anisotropic halo models. Even the
sign of the signal can be changed. Restricting attention to low energy events,
the models predict that the maximum rate occurs in December, and not in June.

</DOC>
<DOC>
<DOCNO> 39813 </DOCNO>
Ratio of Electron Scattering from Nuclei to Deuterium at low x and low


  We have extracted ratios of cross sections for scattering electrons from high
mass targets compared to low mass targets in the region of x ~ 0.02 and Q^2 < 1
(GeV/c)^2 from SLAC experiments performed over the past three decades.
Additional analysis was needed for radiative corrections, target end caps and
calibration runs. We observe no significant difference in the nuclear ratio for
low Q^2 compared to results at Q^2 > 1.

</DOC>
<DOC>
<DOCNO> 72124 </DOCNO>
Recent Results on BFKL Physics


  Virtual photon scattering in $e^+e^-$ collisions can result in events with
the electron-positron pair produced at large rapidity separation in association
with hadrons. The BFKL equation resums large logarithms that dominate the cross
section for this process. After a brief overview of analytic BFKL resummation
and its experimental status, we report on a Monte Carlo method for solving the
BFKL equation that allows kinematic constraints to be taken into account. We
discuss results for $e^+e^-$ collisions using both fixed-order QCD and the BFKL
approach. We conclude with some brief comments on the status of NLL
calculations.

</DOC>
<DOC>
<DOCNO> 151861 </DOCNO>
A Scaling Limit With Many Noncommutativity Parameters


  We derive the worldsheet propagator for an open string with different
magnetic fields at the two ends, and use it to compute two distinct
noncommutativity parameters, one at each end of the string. The usual scaling
limit that leads to noncommutative Yang-Mills can be generalized to a scaling
limit in which both noncommutativity parameters enter. This corresponds to
expanding a theory with U(N) Chan-Paton factors around a background U(1)^N
gauge field with different magnetic fields in each U(1).

</DOC>
<DOC>
<DOCNO> 84249 </DOCNO>
On 4-dimensional cosmological models locally embedded in a 5-dimensional


  We employ a theorem due to Campbell to build some simple 4-dimensional
cosmological models which originate from solutions describing waves propagating
along the extra-dimension of a 5-dimensional Ricci-flat space. The dimensional
reduction is performed in the Jordan frame according to the induced-matter
theory of Wesson.

</DOC>
<DOC>
<DOCNO> 117775 </DOCNO>
Harmonizing the RR Lyrae and Clump Distance Scales - Stretching the


  I explore the consequences of making the RR Lyrae and clump giant distance
scales consistent in the solar neighborhood, Galactic bulge and Large
Magellanic Cloud (LMC). I employ two major assumptions: 1) that the absolute
magnitude - metallicity, M_V(RR) - [Fe/H], relation for RR Lyrae stars is
universal, and 2) that absolute I-magnitudes of clump giants, M_I(RC), in
Baade's Window are known (e.g., can be inferred from the local Hipparcos-based
calibration or theoretical modeling). A comparison between the solar
neighborhood and Baade's Window sets M_V(RR) at [Fe/H] = -1.6 in the range
(0.59 +/- 0.05, 0.70 +/- 0.05), somewhat brighter than the statistical parallax
solution. More luminous RR Lyrae stars imply younger ages of globular cluster,
which would be in better agreement with the conclusions from the currently
favored stellar evolution and cosmological models. A comparison between Baade's
Window and the LMC sets the M_I^{LMC}(RC) in the range (-0.33 +/- 0.09, -0.53
+/- 0.09). The distance modulus to the LMC, mu^{LMC}, is between 18.24 +/- 0.08
and 18.44 +/- 0.07. Unlike M_I^{LMC}(RC), this range in mu^{LMC} does NOT
depend on the adopted value of the dereddened LMC clump magnitude,
I_0^{LMC}(RC). I argue that the currently available information is insufficient
to select the correct distance scale with high confidence.

</DOC>
<DOC>
<DOCNO> 85535 </DOCNO>
Coarse-grained field wave function in stochastic inflation


  The wave function for the matter field fluctuations in the infrared sector is
studied within the framework of inflationary cosmology. These fluctuations are
described by a coarse-grained field which takes into account only the modes
with wavelength much bigger than the size of the Hubble horizon. The case of a
power-law expanding universe is considered and it is found that the relevant
phase-space remains coherent under certain circumstances. In this case the
classical stochastic treatment for matter field fluctuations is not valid,
however, for $p > 4.6$, the system loses its coherence and a classical
stochastic approximation is allowed.

</DOC>
<DOC>
<DOCNO> 12406 </DOCNO>
Intermediate spin approach to the tunneling of nano-magnets


  The theory for the quantum tunneling of nano-magnets is developed within the
intermediate spin framework. Periodic magnetic effects are seen to reflect that
associated with a change of flux by a single flux quantum $\Phi_{0}$. Essential
are Schr\"odinger cat wave functions which involve superpositions of different
magnitudes of the applied magnetic field. For systems in which the tunneling
paths are not co-planar the theory leads to essentially complex magnetic fields
although the expectation values of the fields remain real. In general the
ground states correspond to minimal uncertainty squeezed states. The degree of
squeezing depends on the anisotropy parameters.

</DOC>
<DOC>
<DOCNO> 100158 </DOCNO>
On products of harmonic forms


  We prove that manifolds admitting a Riemannian metric for which products of
harmonic forms are harmonic satisfy strong topological restrictions, some of
which are akin to properties of flat manifolds. Others are more subtle, and are
related to symplectic geometry and Seiberg-Witten theory.
  We also prove that a manifold admits a metric with harmonic forms whose
product is not harmonic if and only if it is not a rational homology sphere.

</DOC>
<DOC>
<DOCNO> 70934 </DOCNO>
Spectrum and decay matrix elements of B and D-mesons in lattice NRQCD


  We discuss recent results on the excitation spectra of B and D-mesons
obtained in the framework of non-relativistic lattice QCD in the quenched
approximation. The results allow for the determination of the $\msbar$-mass of
$m_{b,\msbar}(m_{b,\msbar})= 4.34(7)$ GeV in ${\cal O}(\alpha_s^3)$ in the
perturbative matching. The determination of the decay constants f_{B_s} and
f_{D_s} is discussed in detail. Results for the matrix elements of
semi-leptonic B to D decays are shown.

</DOC>
<DOC>
<DOCNO> 101595 </DOCNO>
Dual 2-complexes in 4-manifolds


  Concerns decompositions of smooth 4-manifolds as the union of two
handlebodies, each with handles of index <=2 (``Heegard''
decompositions).Sample result: Two 2-complexes are (up to 2-deformation) dual
spines of a Heegard decomposition of the 4-sphere if and only if they satisfy
the conclusions of the Alexander-Lefshetz duality theorem ($H_1K\simeq H^2L$
and $H_2K\simeq H^1L$).

</DOC>
<DOC>
<DOCNO> 117996 </DOCNO>
Rapid fading of optical afterglows as evidence for beaming in gamma-ray


  Based on the refined dynamical model proposed by us earlier for beamed
$\gamma$-ray burst ejecta, we carry out detailed numerical procedure to study
those $\gamma$-ray bursts with rapidly fading afterglows (i.e., $\sim t^{-2}$).
It is found that optical afterglows from GRB 970228, 980326, 980519, 990123,
990510 and 991208 can be satisfactorily fitted if the $\gamma$-ray burst ejecta
are highly collimated, with a universal initial half opening angle $\theta_0
\sim 0.1$. The obvious light curve break observed in GRB 990123 is due to the
relativistic-Newtonian transition of the beamed ejecta, and the rapidly fading
optical afterglows come from synchrotron emissions during the mildly
relativistic and non-relativistic phases. We strongly suggest that the rapid
fading of afterglows currently observed in some $\gamma$-ray bursts is evidence
for beaming in these cases.

</DOC>
<DOC>
<DOCNO> 84251 </DOCNO>
Highly Excited Friedmann Universe


  A highly excited Friedmann universe filled with a scalar field and radiation
has been considered. On the basis of a direct solution to the
quantum-mechanical problem with a well-defined time variable, it has been shown
that such a universe can have features (energy density, scale factor, Hubble
constant, density parameter, matter mass, equivalent number of baryons, age,
dimensions of large-scale fluctuations, amplitude of fluctuations of cosmic
microwave background radiation temperature) identical to those of the currently
observed Universe.

</DOC>
<DOC>
<DOCNO> 13012 </DOCNO>
Decay of metastable phase on several types of heterogeneous centers


  A system of a metastable phase with several sorts of the heterogeneous
centers is considered. An analytical theory for the process of decay in such a
system has been constructed. The free energy of formation of the critical
embryo is assumed to be known in the macroscopic approach as well as the energy
of solvatation. The process is split into some periods and the analytical
description of every period is given. The most difficult to describe is the
period of the essential formation of the embryos of a new phase. At first some
asymptotes are investigated and then a general solution is suggested. Several
approximate transformations are accomplished with the corresponding numerical
estimates and some analytical justifications.

</DOC>
<DOC>
<DOCNO> 84233 </DOCNO>
Detection of gravitational waves from inspiraling compact binaries using


  We formulate the data analysis problem for the detection of the Newtonian
waveform from an inspiraling compact-binary by a network of arbitrarily
oriented and arbitrarily distributed laser interferometric gravitational wave
detectors. We obtain for the first time the relation between the optimal
statistic and the magnitude of the network correlation vector, which is
constructed from the matched network-filter. This generalizes the calculation
reported in an earlier work (gr-qc/9906064), where the detectors are taken to
be coincident.

</DOC>
<DOC>
<DOCNO> 9376 </DOCNO>
Phase separation and the possibility of orbital liquid states in CMR


  139La NMR spin-lattice relaxation rate 1/T1 and rf enhancement experiments
provide evidence that the low temperature regime of the ferromagnetic (FM)
phase of La1-xCaxMnO3 segregates into highly-conductive and poorly-conductive
FM regions, associated with differences in the orbital structure. Remarkably,
phase separation is accompanied with the appearance of an extra NMR signal from
FM regions with vanishingly small magnetic anisotropy. This feature has been
attributed to the appearance of regions with strong orbital fluctuations,
resembling droplets of an orbital liquid within the inhomogeneous FM matrix.

</DOC>
<DOC>
<DOCNO> 69800 </DOCNO>
Numerical Study of Dense Adjoint Matter in Two Color QCD


  We identify the global symmetries of SU(2) lattice gauge theory with N
flavors of staggered fermion in the presence of a quark chemical potential mu,
for fermions in both fundamental and adjoint representations, and anticipate
likely patterns of symmetry breaking at both low and high densities. Results
from numerical simulations of the model with N=1 adjoint flavor on a 4^3x8
lattice are presented, using both hybrid Monte Carlo and Two-Step Multi-Boson
algorithms. It is shown that the sign of the fermion determinant starts to
fluctuate once the model enters a phase with non-zero baryon charge density.
HMC simulations are not ergodic in this regime, but TSMB simulations retain
ergodicity even in the dense phase, and in addition appear to show superior
decorrelation. The HMC results for the equation of state and the pion mass show
good quantitative agreement with the predictions of chiral perturbation theory,
which should hold only for N>=2. The TSMB results incorporating the sign of the
determinant support a delayed onset transition, consistent with the pattern of
symmetry breaking expected for N=1.

</DOC>
<DOC>
<DOCNO> 152053 </DOCNO>
Monodromic strings


  We argue that apart from the standard closed and open strings one may
consider a third possibility that we call monodromic strings. The monodromic
string propagating on a target looks like an ordinary open string (a mapping
from a segment to the target) but its space of states is isomorphic to that of
a closed string.
 It is shown that the monodromic strings naturally appear in T-dualizing closed
strings moving on simply connected targets. As a nontrivial topology changing
example we show that the monodromic strings on a compact Poisson-Lie group are
T-dual to the standard closed strings propagating on the noncompact dual PL
group.

</DOC>
<DOC>
<DOCNO> 117094 </DOCNO>
Efficiency of different numerical methods for solving Redfield equations


  The numerical efficiency of different schemes for solving the Liouville-von
Neumann equation within multilevel Redfield theory has been studied. Among the
tested algorithms are the well-known Runge-Kutta scheme in two different
implementations as well as methods especially developed for time propagation:
the Short Iterative Arnoldi, Chebyshev and Newtonian propagators. In addition,
an implementation of a symplectic integrator has been studied. For a simple
example of a two-center electron transfer system we discuss some aspects of the
efficiency of these methods to integrate the equations of motion. Overall for
time-independent potentials the Newtonian method is recommended. For
time-dependent potentials implementations of the Runge-Kutta algorithm are very
efficient.

</DOC>
<DOC>
<DOCNO> 40336 </DOCNO>
Measurement of dsigma/dy for high mass Drell-Yan e+e- Pairs at CDF


  We report on the first measurement of the rapidity distribution dsigma/dy
over nearly the entire kinematic region of rapidity for e+e- pairs in the
Z-boson region of 66<M_ee<116 GeV/c2 and at higher mass M_ee>116 GeV/c2. The
data sample consists of 108 pb-1 of pbar-p collisions at sqrt{s}=1.8 TeV taken
by the Collider Detector at Fermilab during 1992--1995. The total cross section
in the Z-boson region is measured to be 252 +- 11 pb. The measured total cross
section and dsigma/dy are compared with quantum chromodynamics calculations in
leading and higher orders.

</DOC>
<DOC>
<DOCNO> 13339 </DOCNO>
Non-Linear Transport through a Molecular Nanojunction


  We present a simple model of electrical transport through a
metal-molecule-metal nanojunction that includes charging effects as well as
aspects of the electronic structure of the molecule. The interplay of a large
charging energy and an asymmetry of the metal-molecule coupling can lead to
various effects in non-linear electrical transport. In particular, strong
negative differential conductance is observed under certain conditions.

</DOC>
<DOC>
<DOCNO> 11636 </DOCNO>
An Introduction to Breakdown Phenomena in Disordered Systems


  The rupture of a medium under stress typifies breakdown phenomena. More
generally, the latter encompass the dynamics of systems of many interacting
elements governed by the interplay of a driving force with a pinning disorder,
resulting in a macroscopic transition. A simple mean-field formalism
incorporating these features is presented and applied to systems representative
of fracture phenomena, social dilemmas, and magnets out of equilibrium. The
similarities and differences in the corresponding mathematical structures are
emphasized. The solutions are best obtained from a graphical method, from which
very general conclusions may be drawn. In particular, the various classes of
disorder distribution are treated without reference to a particular analytical
or numerical form, and are found to lead to qualitatively different
transitions. Finally, the notion of effective (or phenomenological) theory is
introduced and illustrated for non-equilibrium disordered magnets.

</DOC>
<DOC>
<DOCNO> 174436 </DOCNO>
Energy Dependence of the Near-Threshold Total Cross-Section for the pp


  Total cross sections for the pp --> pp eta' reaction have been measured in
the excess energy range from Q = 1.53 MeV to Q = 23.64 MeV. The experiment has
been performed at the internal installation COSY-11 using a stochastically
cooled proton beam of the COoler SYnchrotron COSY and a hydrogen cluster
target. The determined energy dependence of the total cross section weakens the
hypothesis of the S-wave repulsive interaction between the eta' meson and the
proton. New data agree well with predictions based on the phase-space
distribution modified by the proton-proton final-state-interaction (FSI) only.

</DOC>
<DOC>
<DOCNO> 101439 </DOCNO>
A universal bound for surfaces in 3-manifolds with a given Heegaard


  It is shown that for given positive integers g and b, there is a number
C(g,b), such that any orientable compact irreducible 3-manifold of Heegaard
genus g has at most C(g,b) disjoint, nonparallel incompressible surfaces with
first Betti number b_1 < b.

</DOC>
<DOC>
<DOCNO> 121570 </DOCNO>
Cerenkov Line-like Radiation, The Extended and Improved Formulae System


  You & Cheng (1980) argued that, for relativistic electrons moving through a
dense gas, the Cerenkov effect will produce peculiar atomic and/or molecular
emission lines--Cerenkov lines. They presented a series of formulae to describe
the new line-mechanism. Elegant experimental confirmation has been obtained by
Xu. et al. in the laboratory which definitely verified the existence of
Cerenkov lines. Owing to the potential importance in high energy astrophysics,
in this paper we give a more detailed physical discussion of the emission
mechanisms and improve the previous formulae system into a form which is more
convenient for astrophysical application. Specifically, the extended formulae
in this paper can be applied to other species of atoms and/or ions rather than
hydrogen as in the previous paper, and also to X-ray astronomy. They can also
be used for the calculation of a nonuniform plane-parallel slab of the emissive
gas.

</DOC>
<DOC>
<DOCNO> 100097 </DOCNO>
Chern numbers for singular varieties and elliptic homology


  A fundamental goal of algebraic geometry is to do for singular varieties
whatever we can do for smooth ones. Intersection homology, for example,
directly produces groups associated to any variety which have almost all the
properties of the usual homology groups of a smooth variety. Minimal model
theory suggests the possibility of working more indirectly by relating any
singular variety to a variety which is smooth or nearly so.
  Here we use ideas from minimal model theory to define some characteristic
numbers for singular varieties, generalizing the Chern numbers of a smooth
variety. This was suggested by Goresky and MacPherson as a next natural
problem after the definition of intersection homology. We find that only a
subspace of the Chern numbers can be defined for singular varieties. A
convenient way to describe this subspace is to say that a smooth variety has a
fundamental class in complex bordism, whereas a singular variety can at most
have a fundamental class in a weaker homology theory, elliptic homology. We
use this idea to give an algebro-geometric definition of elliptic homology:
``complex bordism modulo flops equals elliptic homology.''

</DOC>
<DOC>
<DOCNO> 100242 </DOCNO>
1.Classical and Modern Topology. 2.Topological Phenomena in Real World


  Hystory of topology is discussed uncluding the Golden Age Period (1950-1970),
the Period of Decay (1970-1980) and the Period of Recovery in 80s and 90s based
on the ideas borrowed from physics community. In the second part recent result
of the present author, A.Malcev, I Dynnikov and A.Zorich concerning new
observable topological phenomena in normal metals and topology of quasiperiodic
functions on the plane are presented

</DOC>
<DOC>
<DOCNO> 178791 </DOCNO>
Pairing-induced localization of the particle continuum in weakly bound


  The Hartree-Fock-Bogolyubov (HFB) problem for the cutoff local energy-density
functional is solved numerically by using the Gor'kov formalism with an exact
treatment of the particle continuum. The contributions from the resonant and
"gas" continuum to the spectral density of the HFB eigenstates as well as the
shifting and broadening of the discrete HF hole orbitals are clearly
demonstrated with the illustrative example of the drip-line nucleus ^{70}Ca.
The structure of the neutron density distribution in the localized ground state
is analyzed, and the formation of its extended tail ("halo") is shown to be a
collective pairing effect.

</DOC>
<DOC>
<DOCNO> 101307 </DOCNO>
On abelian generalized vertex algebras


  This paper studies the algebraic aspect of a general abelian coset theory
with a work of Dong and Lepowsky as our main motivation. It is proved that the
vacuum space $\Omega_{V}$ (or the space of highest weight vectors) of a
Heisenberg algebra in a general vertex operator algebra $V$ has a natural
generalized vertex algebra structure in the sense of Dong and Lepowsky and that
the vacuum space $\Omega_{W}$ of a $V$-module $W$ is a natural
$\Omega_{V}$-module. The automorphism group $\Aut_{\Omega_{V}}\Omega_{V}$ of
the adjoint $\Omega_{V}$-module is studied and it is proved to be a central
extension of a certain torsion free abelian group by $\C^{\times}$. For certain
subgroups $A$ of $\Aut_{\Omega_{V}}\Omega_{V}$, certain quotient algebras
$\Omega_{V}^{A}$ of $\Omega_{V}$ are constructed. Furthermore, certain functors
among the category of $V$-modules, the category of $\Omega_{V}$-modules and the
category of $\Omega_{V}^{A}$-modules are constructed and irreducible
$\Omega_{V}$-modules and $\Omega_{V}^{A}$-modules are classified in terms of
irreducible $V$-modules. If the category of $V$-modules is semisimple, then it
is proved that the category of $\Omega_{V}^{A}$-modules is semisimple.

</DOC>
<DOC>
<DOCNO> 116521 </DOCNO>
Statistical mechanics of the shallow water system


  We extend the formalism of the statistical theory developed for the 2D Euler
equation to the case of shallow water system. Relaxation equations towards the
maximum entropy state are proposed, which provide a parametrization of sub-grid
scale eddies in 2D compressible turbulence.

</DOC>
<DOC>
<DOCNO> 67786 </DOCNO>
The Influence of Multiplicity Fluctuation on the Erraticity Behaviour in


  The influence of multiplicity distribution (fluctuation of multiplicity in
the event space) on the erraticity behaviour in high energy collisions is
investigated via Monte Carlo simulation and compared with the experimental
results from NA27 data. It is shown that, the erraticity phenomenon is
insensitive to the multiplicity fluctuation. When the average multiplicity is
low, this phenomenon is dominated by the statistical fluctuations also in the
case of multiplicities, fluctuating from event to event.

</DOC>
<DOC>
<DOCNO> 69897 </DOCNO>
Gluons in the QCD bound state problem - a way to exact solution


  The colored objects -- quarks and gluons -- being confined in a small volume
$V\sim R_0^3,$ $R_0\sim 0.5$fm inside the QCD bound state get there not small
masses $m_{q\bar q}\sim 1$GeV, $m_g\sim 0.5$GeV. This drastically simplifies
the QCD dynamics, as now the probabilities e.g. of production of one extra
massive valent gluon or extra $q\bar q$ pair, turned to be small due to a large
gap between corresponding energy levels. The ordinary quantum mechanical
perturbation theory calculations made in the paper shows that corresponding
dimensionless transition amplitudes
$\Lambda_{MH}=\frac{V_{MH}}{|E^{(0)}_M-E^{(0)}_H|}$ (from meson $q\bar q$ to
the hybrid $q\bar qg$) have a value of 20--25% and the mixing of hybrid with
glueball $(gg)$ is even smaller (of the order of 10--18%). Taking into account
all such mixings with all highly lying Fock states is equivalent to the exact
solution of QCD bound state problem. This can be done really summing the small
perturbation theory results for these states contributions.

</DOC>
<DOC>
<DOCNO> 102515 </DOCNO>
The local Langlands correspondence for GL(n) over p-adic fields


  This work is intended as an introduction to the statement and the
construction of the local Langlands correspondence for GL(n) over p-adic
fields. The emphasis lies on the statement and the explanation of the
correspondence.

</DOC>
<DOC>
<DOCNO> 170365 </DOCNO>
Quantum Bayes rule


  We state a quantum version of Bayes's rule for statistical inference and give
a simple general derivation within the framework of generalized measurements.
The rule can be applied to measurements on N copies of a system if the initial
state of the N copies is exchangeable. As an illustration, we apply the rule to
N qubits. Finally, we show that quantum state estimates derived via the
principle of maximum entropy are fundamentally different from those obtained
via the quantum Bayes rule.

</DOC>
<DOC>
<DOCNO> 116812 </DOCNO>
Universal quantification for deterministic chaos in dynamical systems


  A cell dynamical system model for deterministic chaos enables precise
quantification of the round-off error growth,i.e., deterministic chaos in
digital computer realizations of mathematical models of continuum dynamical
systems. The model predicts the following: (a) The phase space trajectory
(strange attractor) when resolved as a function of the computer accuracy has
intrinsic logarithmic spiral curvature with the quasiperiodic Penrose tiling
pattern for the internal structure. (b) The universal constant for
deterministic chaos is identified as the steady-state fractional round-off
error k for each computational step and is equal to 1 /sqr(tau) (=0.382) where
tau is the golden mean. (c) The Feigenbaum's universal constants a and d are
functions of k and, further, the expression 2(a**2) = (pie)*d quantifies the
steady-state ordered emergence of the fractal geometry of the strange
attractor. (d) The power spectra of chaotic dynamical systems follow the
universal and unique inverse power law form of the statistical normal
distribution.

</DOC>
<DOC>
<DOCNO> 99968 </DOCNO>
Matrix exponential


  I try to show how natural and efficient is the use of Hermite interpolation
polynomials in the computation of matrix exponentials and partial fraction
decompositions.

</DOC>
<DOC>
<DOCNO> 122535 </DOCNO>
Models for SNeIa and Evolutionary Effects with Redshift


  Based on detailed models for the explosions, light curves and NLTE-spectra,
evolutionary effects of Type Ia Supernovae (SNe Ia) with redshift have been
studied to evaluate their size on cosmological time scales,how the effects can
be recognized and how one may be able to correct for them. We show that delayed
detonation models can account for the majority of observations of spectra and
LCs. IR observations are a new and powerful tools to constrain explosion
models, e.g. by a strong MgII line at propagation in the WD. A strong Mg II
line at 1.05 mu shows that nuclear burning takes place at the outer, low
density layers. This requires a transition from the deflagration to the
detonation regime of the nuclear burning front, or a very fast deflagration. We
put the models into context with the empirical brightness decline relation
which is widely applied to use SNe Ia as yardsticks on cosmological distance
scales. This relation can be well understood in the framework of M(Ch)-WDs as a
consequence of the opacity effects in combination with the amount of 56Ni which
determines the brightness. We show that evolution may produce an offset in the
brightness decline relation but it is restricted to a few tenth of a magnitude.
Effects reveal themself by changes in the U and UV fluxes, and in a change in
the maximum brightness/decline relation by DM is about 0.1Dt where Dt is the do
difference between local and distant SN-samples. According to new data by Alde-
ring et al.(2000), Dt<1day and, likely, evolution will not eliminate Lambda.

</DOC>
<DOC>
<DOCNO> 71236 </DOCNO>
Hot Scalar Theory in Large N: Bose-Einstein Condensation


  I review the Bose-Einstein condensation phase transition of dilute gases of
cold atoms, for particle theorists acquainted with methods of field theory at
finite temperature. I then discuss how the dependence of the phase transition
temperature on the interaction strength can be computed in the large N
approximation.

</DOC>
<DOC>
<DOCNO> 8633 </DOCNO>
Particles Sliding on a Fluctuating Surface: Phase Separation and Power


  We study a system of hard-core particles sliding downwards on a fluctuating
one-dimensional surface which is characterized by a dynamical exponent $z$. In
numerical simulations, an initially random particle density is found to coarsen
and obey scaling with a growing length scale $\sim t^{1/z}$. The structure
factor deviates from the Porod law in some cases. The steady state is unusual
in that the density-segregation order parameter shows strong fluctuations. The
two-point correlation function has a scaling form with a cusp at small argument
which we relate to a power law distribution of particle cluster sizes. Exact
results on a related model of surface depths provides insight into the origin
of this behaviour.

</DOC>
<DOC>
<DOCNO> 13823 </DOCNO>
Degree Distributions of Growing Networks


  The in-degree and out-degree distributions of a growing network model are
determined. The in-degree is the number of incoming links to a given node (and
vice versa for out-degree. The network is built by (i) creation of new nodes
which each immediately attach to a pre-existing node, and (ii) creation of new
links between pre-existing nodes. This process naturally generates correlated
in- and out-degree distributions. When the node and link creation rates are
linear functions of node degree, these distributions exhibit distinct power-law
forms. By tuning the parameters in these rates to reasonable values, exponents
which agree with those of the web graph are obtained.

</DOC>
<DOC>
<DOCNO> 120097 </DOCNO>
On the transport of magnetic fields by solar-like stratified convection


  The interaction of magnetic fields and stratified convection was studied in
the context of the solar and late type stellar dynamos by using numerical 3D
MHD simulations. The topology of stratified asymmetric and over-turning
convection enables a pumping mechanism that may render the magnetic flux
storage problem obsolete. The inclusion of open boundary conditions leads to a
considerable flux loss unless the open boundary is placed close to the physical
boundary. Simulations including solar-like latitudinal shear indicates that a
toroidal field of several tens of kilo-Gauss may be held down by the pumping
mechanism.

</DOC>
<DOC>
<DOCNO> 9785 </DOCNO>
Details of disorder matter in 2D d-wave superconductors


  We demonstrate that discrepancies between predicted low-energy quasiparticle
properties in disordered 2D d-wave superconductors occur because of the
unanticipated importance of disorder model details and normal-state
particle-hole symmetry. This conclusion follows from numerically exact
evaluations of the quasiparticle density-of-states predicted by the
Bogoliubov-deGennes (BdG) mean field equations for both binary alloy and random
site energy disorder models. For the realistic case, which is best described by
a binary alloy model without particle-hole symmetry, we predict
density-of-states suppression below an energy scale which appears to be
correlated with the corresponding single-impurity resonance.

</DOC>
<DOC>
<DOCNO> 119350 </DOCNO>
The Eta Chamaeleontis Cluster: Origin in the Sco-Cen OB Association


  A young, nearby compact aggregate of X-ray emitting pre-main sequence stars
was recently discovered in the vicinity of eta Cha (B8V). In this paper, we
further investigate this cluster: its membership, its environs and origins.
ROSAT HRI X-ray data for the cluster's T Tauri stars show high levels of
magnetic activity and variability. The cluster has an anomalous X-ray
luminosity function compared to other young clusters, deficient in stars with
low, but detectable X-ray luminosities. This suggests that many low-mass
members have escaped the surveyed core region. Photographic photometry from the
USNO-A2.0 catalog indicates that additional, X-ray-quiet members exist in the
cluster core region. The components of the eclipsing binary RS Cha, previously
modeled in the literature as post-MS with discordant ages, are shown to be
consistent with being coeval pre-MS stars. We compute the Galactic motion of
the cluster from Hipparcos data, and compare it to other young stars and
associations in the fourth Galactic quadrant. The kinematic study shows that
the eta Cha cluster, the TW Hya association, and a new group near epsilon Cha,
probably originated near the giant molecular cloud complex that formed the two
oldest subgroups of the Sco-Cen OB association roughly 10-15 Myr ago. Their
dispersal is consistent with the velocity dispersions seen in giant molecular
clouds. A large H I filament and dust lane located near eta Cha has been
identified as part of a superbubble formed by Sco-Cen OB winds and supernova
remnants. The passage of the superbubble may have terminated star-formation in
the eta Cha cluster and dispersed its natal molecular gas.

</DOC>
<DOC>
<DOCNO> 118850 </DOCNO>
On the Poynting-Robertson Effect and Analytical Solutions


  Solutions of the two-body problem with the simultaneous action of the solar
electromagnetic radiation in the form of the Poynting-Robertson effect are
discussed. Special attention is devoted to pseudo-circular orbits and terminal
values of osculating elements. The obtained results complete those of Klacka
and Kaufmannova (1992) and Breiter and Jackson (1998). Terminal values of
osculating elements presented in Breiter and Jackson (1998) are of no physical
sense due to the fact that relativistic equation of motion containing only
first order of $\vec{v}/c$ was used in the paper.

</DOC>
<DOC>
<DOCNO> 117447 </DOCNO>
Derivation of a Sample of Gamma-Ray Bursts from BATSE DISCLA Data


  We have searched for gamma-ray bursts (GRBs) in the BATSE DISCLA data over a
time period of 5.9 years. We employ a trigger requiring an excess of at least 5
sigma over background for at least two modules in the 50-300 keV range. After
excluding certain geographic locations of the satellite, we are left with 4485
triggers. Based on sky positions, we exclude triggers close to the sun, to Cyg
X-1, to Nova Persei 1992 and the repeater SGR 1806-20, while these sources were
active. We accept 1013 triggers that correspond to GRBs in the BATSE catalog,
and after visual inspection of the time profiles classify 378 triggers as
cosmic GRBs. We denote the 1391 GRBs so selected as the "BD2 sample". The BD2
sample effectively represents 2.003 years of full sky coverage for a rate of
694 GRBs per year. Euclidean V/Vmax values have been derived through
simulations in which each GRB is removed in distance until the detection
algorithm does not produce a trigger. The BD2 sample produces a mean value
<V/Vmax> = 0.334 +- 0.008.

</DOC>
<DOC>
<DOCNO> 84465 </DOCNO>
Dilatonic p-Branes and Brane Worlds


  We study a general dilatonic p-brane solution in arbitrary dimensions in
relation to the Randall-Sundrum scenario. When the p-brane is fully localized
along its transverse directions, the Kaluza-Klein zero mode of bulk graviton is
not normalizable. When the p-brane is delocalized along its transverse
directions except one, the Kaluza-Klein zero mode of bulk graviton is
normalizable if the warp factor is chosen to increase, in which case there are
singularities at finite distance away from the p-brane. Such delocalized
p-brane can be regarded as a dilatonic domain wall as seen in higher
dimensions. This unusual property of the warp factor allows one to avoid a
problem of dilatonic domain wall with decreasing warp factor that free massive
particles are repelled from the domain wall and hit singularities, since
massive particles with finite energy are trapped around delocalized p-branes
with increasing warp factor by gravitational force and can never reach the
singularities.

</DOC>
<DOC>
<DOCNO> 170196 </DOCNO>
Security of Continuous Variable Quantum Cryptography


  We discuss a quantum key distribution scheme in which small phase and
amplitude modulations of CW light beams carry the key information. The presence
of EPR type correlations provides the quantum protection. We identify universal
constraints on the level of shared information between the intended receiver
(Bob) and any eavesdropper (Eve) and use this to make a general evaluation of
security. We identify teleportation as an optimum eavesdropping technique.

</DOC>
<DOC>
<DOCNO> 11952 </DOCNO>
Kinetic Capacity of a Protein


  The ability of a protein to recognise multiple independent target
conformations was demonstrated in [1]. Here we consider the recognition of
correlated configurations, which we apply to funnel design for a single
conformation. The maximum basin of attraction, as parametrised in our model,
depends on the number of amino acid species as ln A, independent of protein
length. We argue that the extent to which the protein energy landscape can be
manipulated is fixed, effecting a trade-off between well breadth, well depth
and well number. This clarifies the scope and limits of protein and
heteropolymer function.

</DOC>
<DOC>
<DOCNO> 13996 </DOCNO>
On the theory of thermoelectric phenomena in superconductors


  The theory of thermoelectric effects in superconductors is discussed in
connection to the recent publication by Marinescu and Overhauser, Phys. Rev. B
55, 11637 (1997). We argue that the charge on-conservation arguments by
Marinescu and Overhauser do not require any revision of the Boltzmann transport
equation in superconductors, and show that their ``electron-conserving
transport theory'' contradicts thermodynamics. Possible mechanisms responsible
for the discrepancy between some experimental data and the theory by Galperin,
Gurevich, and Kozub, JETP Lett. 17, 476 (1973) are discussed.

</DOC>
<DOC>
<DOCNO> 178746 </DOCNO>
Nucleon Resonances in Meson Nucleon Scattering with Strangeness


  An effective Lagrangian model in a coupled channels framework is applied to
extract nucleon resonance parameters. In the K-matrix approximation, we
simultaneously analyze all the available data for the transitions from pi N to
five possible meson-baryon final states, pi N, pipi N, eta N, K Lambda, and
KSigma, in the energy range from pi N threshold up to W = 2 GeV. In this work,
we focus our efforts on the K Sigma channel. In particular, we include a set of
Delta resonances around 1900 MeV: the S31(1900), P31(1910), and P33(1920)
states. In most cases the parameters of nucleon resonances determined by the
fits are consistent with the commonly accepted values in the literature. We
find that in the low-energy region, the S11(1650), P11(1710), and P13(1720)
states are important for the p(pi-,K0)Sigma0 and p(pi-,K+)Sigma- processes
while the P33(1600) and D33(1700) states are significant for the pure I=3/2
reaction p(pi+,K+)Sigma+. In the high energy region, we find a D13 state at
1945 MeV which is important for the p(pi-,K0)Sigma0 reaction while the Delta
resonances around 1900 MeV show up significantly in the p(pi-,K+)Sigma- and
p(pi+,K+)Sigma+ processes.

</DOC>
<DOC>
<DOCNO> 152417 </DOCNO>
Supersymmetric Conical Defects: Towards a string theoretic description


  Conical defects, or point particles, in AdS_3 are one of the simplest
non-trivial gravitating systems, and are particularly interesting because black
holes can form from their collision. We embed the BPS conical defects of three
dimensions into the N=4b supergravity in six dimensions, which arises from IIB
string theory compactified on K3. The required Kaluza-Klein reduction of the
six dimensional theory on a sphere is analyzed in detail, including the
relation to the Chern-Simons supergravities in three dimensions. We show that
the six dimensional spaces obtained by embedding the 3d conical defects arise
in the near-horizon limit of rotating black strings. Various properties of
these solutions are analyzed and we propose a representation of our defects in
the CFT dual to asymptotically AdS_3 x S^3 spaces. Our work is intended as a
first step towards analyzing colliding defects that form black holes.

</DOC>
<DOC>
<DOCNO> 101619 </DOCNO>
Duality and the Equivalence Principle of Quantum Mechanics


  Following a suggestion by Vafa, we present a quantum-mechanical model for
S-duality symmetries observed in the quantum theories of fields, strings and
branes. Our formalism may be understood as the topological limit of Berezin's
metric quantisation of the upper half-plane H, in that the metric dependence
has been removed. Being metric-free, our prescription makes no use of global
quantum numbers. Quantum numbers arise only locally, after the choice of a
local vacuum to expand around. Our approach may be regarded as a manifestly non
perturbative formulation of quantum mechanics, in that we take no classical
phase space and no Poisson brackets as a starting point. The reparametrisation
invariance of H under SL(2,R) induces a natural SL(2,R) action on the quantum
mechanical operators that implements S-duality. We also link our approach with
the equivalence principle of quantum mechanics recently formulated by Faraggi
and Matone.

</DOC>
<DOC>
<DOCNO> 118496 </DOCNO>
Speckle Imaging: a boon for astronomical observations


  The speckle imaging is a photographic technique that resolves objects viewed
through severely distorted media. The results are insensitive to the errors
caused by apparent size of the isoplanatic patch and the telescope aberrations.
In this article, a short descriptions of the atmospheric turbulence and its
effect on the flat wavefront from a stellar source is presented; the
shortcomings of the conventional long-exposure images in the presence of
Earth's atmosphere are discussed. The advantages of the speckle interferometric
technique over conventional imaging are enumerated. The technical details of
the method, basic Fourier optics, data analysis procedures are also described.

</DOC>
<DOC>
<DOCNO> 101676 </DOCNO>
Canonical abelianization of finite group actions


  In these notes we present a corrected version of the algorithm for
abelianization of stabilizers of finite group actions on smooth manifolds using
equivariant blow ups.

</DOC>
<DOC>
<DOCNO> 67648 </DOCNO>
The $K_L\to\pi^0\nu\bar\nu$ Decay in Models of Extended Scalar Sector


  We calculate new contributions to the $K_L\to\pi^0\nu\bar\nu$ decay in models
where neutrino Majorana masses require an extension of the scalar sector.
First, we study a model where the neutrino mass is induced by the vacuum
expectation value of an SU(2)-triplet scalar. Second, we study the Zee model
where the Majorana mass comes from one loop diagrams involving a singly
charged, SU(2)-singlet scalar. In both models, the Yukawa couplings that
involve the new scalar and the neutrinos could be of order one. We find,
however, that the contributions to the $K_L\to\pi^0\nu\bar\nu$ decay mediated
by the new scalars depend on the neutrino masses rather than the Yukawa
couplings and are, therefore, negligibly small.

</DOC>
<DOC>
<DOCNO> 12213 </DOCNO>
Low temperature shape relaxation of 2-d islands by edge diffusion


  We present a precise microscopic description of the limiting step for low
temperature shape relaxation of two dimensional islands in which activated
diffusion of particles along the boundary is the only mechanism of transport
allowed. In particular, we are able to explain why the system is driven
irreversibly towards equilibrium. Based on this description, we present a
scheme for calculating the duration of the limiting step at each stage of the
relaxation process. Finally, we calculate numerically the total relaxation time
as predicted by our results and compare it with simulations of the relaxation
process.

</DOC>
<DOC>
<DOCNO> 39665 </DOCNO>
The Spin Structure of the Proton


  It is shown that the proton "spin crisis'' or "spin puzzle" can be understood
by the relativistic effect of quark transversal motions due to the
Melosh-Wigner rotation. The quark helicity $\Delta q$ measured in polarized
deep inelastic scattering is actually the quark spin in the infinite momentum
frame or in the light-cone formalism, and it is different from the quark spin
in the nucleon rest frame or in the quark model. The flavor asymmetry of the
Melosh-Wigner effect for the valence $u$ and $d$ quarks and the intrinsic sea
$q \bar{q}$ pairs are also the important ingredients in a SU(6)
quark-spectator-diquark model framework to understand the "spin puzzle". Such a
picture of the spin structure can be tested by use of several simple relations
to measure the quark spin distributions in the quark model.

</DOC>
<DOC>
<DOCNO> 150978 </DOCNO>
Entropy of Black Holes in D=5, N=2 Supergravity and AdS Central Charges


  We consider general black holes in D=5, N=2 supergravity coupled to vector
multiplets, and discuss the issue of microstate counting from various
viewpoints. The statistical entropy is computed for the near-extremal case
using the central charge of the $AdS_2$ factor appearing in the near-horizon
geometry. Furthermore, we explicitly construct the duality transformation
connecting electrically charged black holes to magnetically charged black
strings, under which the $AdS_2 \times S^3$ near horizon geometry becomes
$AdS_3 \times S^2$. For $AdS_3$ the counting of microstates correctly
reproduces the Bekenstein-Hawking entropy, thus resolving the discrepancy
previously found for $AdS_2$.

</DOC>
<DOC>
<DOCNO> 85534 </DOCNO>
Slowly Rotating Boson Fermion Stars


  Relativistic prescription is used to study the slow rotation of stars
composed by self-gravitating bosons and fermions (fermions may be considered as
neutrons). Previous results demand that purely boson stars are unable to
display slow rotation, if one uses relativistic prescription with classical
scalar fields. In contrast to this, the present work shows that a combined
boson-neutron star in its ground-state can rotate. Their structure and
stability are analysed under slow rotation approximations.

</DOC>
<DOC>
<DOCNO> 99836 </DOCNO>
One-dimensional double Hecke algebras and Gaussians


  We use one-dimensional double affine Hecke algebras to introduce
q-counterparts of the Gauss integrals and new types of Gauss-Selberg sums at
roots of unity.

</DOC>
<DOC>
<DOCNO> 12753 </DOCNO>
Simplification of protein representation from the contact potentials


  Based on the concept of energy landscape a picture of the mismatch between
the reduced interaction matrix of residues and the matrix of statistical
contact potentials is presented. For the Miyazawa and Jernigan (MJ) matrix,
rational groupings of 20 kinds of residues with minimal mismatches under the
consideration of local minima and statistics on correlation between the
residues are studied. A hierarchical tree of groupings relating to different
numbers of groups $N$ is obtained, and a plateau around $N=8\sim 10$ is found,
which may represent the basic degree of freedom of the sequence complexity of
proteins.

</DOC>
<DOC>
<DOCNO> 121065 </DOCNO>
The Nuclear and Circum-nuclear Stellar Population in Seyfert 2 Galaxies:


  We report the results of a spectroscopic investigation of a sample of 20 of
the brightest type 2 Seyfert nuclei. Our goal is to search for the direct
spectroscopic signature of massive stars, and thereby probe the role of
circumnuclear starbursts in the Seyfert phenomenon. The method used is based on
the detection of the higher order Balmer lines and HeI lines in absorption and
the Wolf-Rayet feature at $\sim$4680 \AA in emission. These lines are strong
indicators of the presence of young (a few Myrs) and intermediate-age (a few
100 Myrs) stellar populations. In over half the sample, we have detected HeI
and/or strong stellar absorption features in the high-order (near-UV) Balmer
series together with relatively weak lines from an old stellar population. In
three others we detect a broad emission feature near 4680 \AA that is most
plausibly ascribed to a population of Wolf-Rayet stars (the evolved descendants
of the most massive stars). We therefore conclude that the blue and near-UV
light of over half of the sample is dominated by young and/or intermediate age
stars. The ``young'' Seyfert 2's have have larger far-IR luminosities, cooler
mid/far-IR colors, and smaller [OIII]/H$\beta$ flux ratios than the ``old''
ones. These differences are consistent with a starburst playing a significant
energetic role in the former class. We consider the possibility that there may
be two distinct sub-classes of Seyfert 2 nuclei (``starbursts'' and ``hidden
BLR''). However, the fact that hidden BLRs have been found in three of the
``young'' nuclei argues against this, and suggests that nuclear starbursts may
be a more general part of the Seyfert phenomenon.

</DOC>
<DOC>
<DOCNO> 12413 </DOCNO>
Metallic slabs: Perturbative treatments based on jellium


  We examine first-order perturbative results based on jellium for the surface
energy of slabs of simple metals, using various local pseudopotentials
(Ashcroft, Heine-Abarenkov and evanescent core). The difference between the
pseudopotential and the jellium potential is averaged along the plane parallel
to the surface. We compare these perturbative results with those of the
stabilized jellium model (a modification of the regular jellium model in which
the perturbation appears in the energy functional right from the outset) and
with the output of other perturbative and non-perturbative calculations.

</DOC>
<DOC>
<DOCNO> 119910 </DOCNO>
Thermal X-ray composites as an effect of projection


  A new possibility to explain the nature of thermal X-ray composites (TXCs),
i.e. a class of supernova remnants (SNRs) with a thermal X-ray centrally-filled
morphology within a radio shell, as a projection effect of the 2- or
3-dimensional shell-like SNR evolved in a nonuniform medium with scale-height
<10 pc is proposed. Both X-ray and radio morphologies, as well as the basic
theoretical features of this kind of SNR and the surrounding medium, are
considered. Theoretical properties of a shell-like SNR evolved at the edge of a
molecular cloud correspond to the observed properties of TXCs if the gradient
of the ambient density does not lie in the projection plane and the magnetic
field is nearly aligned with the line of sight. So, at least a part of objects
from the class may be interpreted within the framework of the considered
effect. The proposed model suggests that SNRs with barrel-like radio and
centrally-brightened thermal X-ray morphologies should exist. The model allows
us to consider TXCs as prospective sources of proton origin gamma-rays.

</DOC>
<DOC>
<DOCNO> 40580 </DOCNO>
Jet Flavour Identification at the CLIC Multi-TeV e+e- Collider


  Jet flavour identification in multi-TeV e+e- collisions is expected to
provide insights on new phenomena at scales beyond those probed by the LHC. The
anticipated high track density and jet collimation represent a new challenge to
jet tagging algorithms. A method, based on the sampling of the jet charged
multiplicity, sensitive to the long decay length and large decay multiplicity
of heavy flavour hadrons is proposed and the expected performances for the
tagging of e+e- -> bb events at 3 TeV are discussed.

</DOC>
<DOC>
<DOCNO> 8521 </DOCNO>
High orders of perturbation theory: are renormalons significant?


  According to Lipatov, the high orders of perturbation theory are determined
by saddle-point configurations (instantons) of the corresponding functional
integrals. According to t'Hooft, some individual large diagrams, renormalons,
are also significant and they are not contained in the Lipatov contribution.
The history of the conception of renormalons is presented, and the arguments in
favor of and against their significance are discussed. The analytic properties
of the Borel transforms of functional integrals, Green functions, vertex parts,
and scaling functions are investigated in the case of \phi^4 theory. Their
analyticity in a complex plane with a cut from the first instanton singularity
to infinity (the Le Guillou - Zinn-Justin hypothesis) is proved. It rules out
the existence of the renormalon singularities pointed out by t'Hooft and
demonstrates the nonconstructiveness of the conception of renormalons as a
whole. The results can be interpreted as an indication of the internal
consistency of \phi^4 theory.

</DOC>
<DOC>
<DOCNO> 70140 </DOCNO>
Phase Transitions in QCD


  At high temperatures or densities, hadronic matter shows different forms of
critical behaviour: colour deconfinement, chiral symmetry restoration, and
diquark condensation. I first discuss the conceptual basis of these phenomena
and then consider the description of colour deconfinement in terms of symmetry
breaking, through colour screening and as percolation transition.

</DOC>
<DOC>
<DOCNO> 99506 </DOCNO>
The generalized Abel-Plana formula. Applications to Bessel functions and


  One of the most efficient methods to obtain the vacuum expectation values for
the physical observables in the Casimir effect is based on the using the
Abel-Plana summation formula. This allows to derive the regularized quantities
by manifestly cutoff independent way and to present them in the form of
strongly converging integrals. However the applications of Abel- Plana formula
in usual form is restricted by simple geometries when the eigenmodes have a
simple dependence on quantum numbers. The author generalized the Abel-Plana
formula which essentially enlarges its application range. Based on this
generalization, formulae have been obtained for various types of series over
the zeros of some combinations of Bessel functions and for integrals involving
these functions. It have been shown that these results generalize the special
cases existing in literature. Further the derived summation formulae have been
used to summarize series arising in the mode summation approach to the Casimir
effect for spherically and cylindrically symmetric boundaries. This allows to
extract the divergent parts from the vacuum expectation values for the local
physical observables in the manifestly cutoff independent way. The present
paper reviews these results. Some new considerations are added as well.

</DOC>
<DOC>
<DOCNO> 14122 </DOCNO>
Charge Transport in Manganites: Hopping Conduction, the Anomalous Hall


  The low-temperature Hall resistivity \rho_{xy} of La_{2/3}A_{1/3}MnO_3 single
crystals (where A stands for Ca, Pb and Ca, or Sr) can be separated into
Ordinary and Anomalous contributions, giving rise to Ordinary and Anomalous
Hall effects, respectively. However, no such decomposition is possible near the
Curie temperature which, in these systems, is close to metal-to-insulator
transition. Rather, for all of these compounds and to a good approximation, the
\rho_{xy} data at various temperatures and magnetic fields collapse (up to an
overall scale), on to a single function of the reduced magnetization
m=M/M_{sat}, the extremum of this function lying at m~0.4. A new mechanism for
the Anomalous Hall Effect in the inelastic hopping regime, which reproduces
these scaling curves, is identified. This mechanism, which is an extension of
Holstein's model for the Ordinary Hall effect in the hopping regime, arises
from the combined effects of the double-exchange-induced quantal phase in
triads of Mn ions and spin-orbit interactions. We identify processes that lead
to the Anomalous Hall Effect for localized carriers and, along the way, analyze
issues of quantum interference in the presence of phonon-assisted hopping. Our
results suggest that, near the ferromagnet-to-paramagnet transition, it is
appropriate to describe transport in manganites in terms of carrier hopping
between states that are localized due to combined effect of magnetic and
non-magnetic disorder. We attribute the qualitative variations in resistivity
characteristics across manganite compounds to the differing strengths of their
carrier self-trapping, and conclude that both disorder-induced localization and
self-trapping effects are important for transport.

</DOC>
<DOC>
<DOCNO> 179003 </DOCNO>
Short-range correlations in nuclear matter using Green's functions


  We treat short-range correlations in nuclear matter, induced by the repulsive
core of the nucleon-nucleon potential, within the framework of a
self-consistent Green's function theory. The effective in-medium interaction
sums the ladder diagrams of both the particle-particle and hole-hole type. The
demand of self-consistency results in a set of nonlinear equations which must
be solved by iteration. We explore the possibility of approximating the
single-particle Green's function by a limited number of poles and residues.

</DOC>
<DOC>
<DOCNO> 14165 </DOCNO>
A nonextensive critical phenomenon scenario for quantum entanglement


  We discuss the paradigmatic bipartite spin-1/2 system having the
probabilities $\frac{1+3x}{4}$ of being in the Einstein-Podolsky-Rosen fully
entangled state $|\Psi^-$$> \equiv \frac{1}{\sqrt
2}(|$$\uparrow>_A|$$\downarrow>_B$$-|$$\downarrow>_A|$$\uparrow>_B)$ and
$\frac{3(1-x)}{4}$ of being orthogonal. This system is known to be separable if
and only if $x\le1/3$ (Peres criterion). This critical value has been recently
recovered by Abe and Rajagopal through the use of the nonextensive entropic
form $S_q \equiv \frac{1- Tr \rho^q}{q-1} (q \in \cal{R}; $$S_1$$= -$ $Tr$ $
\rho \ln \rho)$ which has enabled a current generalization of Boltzmann-Gibbs
statistical mechanics. This result has been enrichened by Lloyd, Baranger and
one of the present authors by proposing a critical-phenomenon-like scenario for
quantum entanglement. Here we further illustrate and discuss this scenario
through the calculation of some relevant quantities.

</DOC>
<DOC>
<DOCNO> 85339 </DOCNO>
A Simple Line Element to the Dilaton Gravity


  The metric to the two-dimensional dilaton gravity can be writen in an
alternative form, similar to the two-dimensional Schwarzschild metric, and
allow us the identification of some quantitiies with those equivalent in the
Schwarzschild solution. This new form, howewer, presents a non-physical
singularity at the horizon in the same way that in the realistic four
dimensional case. We show a procedure to eliminate this horizon singularity
and, as an application, the resulting metric is used to obtain the associated
Hawking temperature. We discuss also some differents between this metric and
the Schwarzcchild one.

</DOC>
<DOC>
<DOCNO> 123334 </DOCNO>
The Formation of Star Clusters


  The ability of HST to resolve objects ten times smaller than possible from
the ground has rejuvenated the study of young star clusters. A recurrent
morphological theme found in nearby resolved sytems is the observation of young
(typically 1 - 10 Myr), massive (10**3 - 10**4 M_sun), compact (rho ~ 10**5
M_sun/pc**3) clusters which have evacuated the gas and dust from a spherical
region around themselves. New stars are being triggered into formation along
the edges of the envelopes, with pillars (similar to the Eagle Nebula) of
molecular gas streaming away from the the regions of star formation. The
prototype for these objects is 30 Doradus. Another major theme has been the
discovery of large numbers of young (typically 1 - 500 Myr), massive (10**3 -
10**7 M_sun), compact star clusters in merging, starbursting, and even some
barred and spiral galaxies. The brightest of these clusters have all the
attributes expected of protoglobular clusters, hence allowing us to study the
formation of globular clusters in the local universe rather than trying to
ascertain how they formed ~14 Gyr ago. The prototype is the Antennae Galaxy.

</DOC>
<DOC>
<DOCNO> 8299 </DOCNO>
Field-Induced Crossover and Colossal Magnetoresistance in


  A field-induced crossover is observed in the resistivity and magnetization
(M) of a La(0.7)Pb(0.3)MnO(3) single crystal. The field-dependence of the
resistivity and M suggests that a small spin-canted species with
mean-field-like interactions dominates at low fields (H), whereas, individual
spins and 3D Ising/Heisenberg models describe the high-H behavior rather well.
Around the ferromagnetic transition, an H-induced destruction of the small
spin-canted magnetic polarons is accompanied by large magnetoresistance.

</DOC>
<DOC>
<DOCNO> 151108 </DOCNO>
Wess-Zumino Terms for the Deformed Skyrme Model


  A formulation of Skyrme model as an embedded gauge theory with the constraint
deformed away from the spherical geometry is proposed. The gauge invariant
formulation is obtained firstly generalizing the intrinsic geometry of the
model and then converting the constraint to first-class through an iterative
Wess-Zumino procedure. The gauge invariant model is quantized via Dirac method
for first-class system. A perturbative calculation provides new free parameters
related to deformation that improve the energy spectrum obtained in earlier
approaches.

</DOC>
<DOC>
<DOCNO> 84252 </DOCNO>
SU(2) Cosmological Solitons


  We present a class of numerical solutions to the SU(2) nonlinear
$\sigma$-model coupled to the Einstein equations with cosmological constant
$\Lambda\geq 0$ in spherical symmetry. These solutions are characterized by the
presence of a regular static region which includes a center of symmetry. They
are parameterized by a dimensionless ``coupling constant'' $\beta$, the sign of
the cosmological constant, and an integer ``excitation number'' $n$. The
phenomenology we find is compared to the corresponding solutions found for the
Einstein-Yang-Mills (EYM) equations with positive $\Lambda$ (EYM$\Lambda$). If
we choose $\Lambda$ positive and fix $n$, we find a family of static spacetimes
with a Killing horizon for $0 \leq \beta < \beta_{max}$. As a limiting solution
for $\beta = \beta_{max}$ we find a {\em globally} static spacetime with
$\Lambda=0$, the lowest excitation being the Einstein static universe. To
interpret the physical significance of the Killing horizon in the cosmological
context, we apply the concept of a trapping horizon as formulated by Hayward.
For small values of $\beta$ an asymptotically de Sitter dynamic region contains
the static region within a Killing horizon of cosmological type. For strong
coupling the static region contains an ``eternal cosmological black hole''.

</DOC>
<DOC>
<DOCNO> 122263 </DOCNO>
Evolution of Gas in Elliptical Galaxies


  We review the origin and structure of hot (cooling flow) gas in elliptical
galaxies. X-ray observations can be used to determine the stellar mass to light
ratio, the mass profiles of dark matter halos, and the interstellar magnetic
field. Interstellar gas cools over a large volume, forming stars with a
bottom-heavy IMF. For consistency with the thin fundamental plane, young stars
must be optically luminous. Circular X-ray isophotes in rotating elliptical
galaxies indicate distributed radiative cooling or strong interstellar
turbulence.

</DOC>
<DOC>
<DOCNO> 178805 </DOCNO>
Interpretation of the First Data on Central Au+Au Collisions at


  We compare three semi-microscopic theories to the first data on particle
production in central Au+Au collisions taken at RHIC by the PHOBOS
collaboration as well as to existing data on central Pb+Pb collisions taken at
the SPS by the NA49 collaboration. LEXUS represents the SPS data quite well but
not the RHIC data, whereas the wounded nucleon model does the opposite. The
collective tube model fails to describe any of the data. This suggests a
transition in the dynamics of particle production between \sqrt{s} = 17 and 56
A GeV as one goes from the SPS to RHIC.

</DOC>
<DOC>
<DOCNO> 170240 </DOCNO>
On the quantum mechanical nature in liquid NMR quantum computing


  The quantum nature of bulk ensemble NMR quantum computing ---the center of
recent heated debate, is addressed. Concepts of the mixed state and
entanglement are examined, and the data in a 2 qubit liquid NMR quantum
computation are analyzed. It is pointed out that the key problem in the current
debate is the understanding of entanglement in a mixed state system. The
following points are concluded in this Letter: 1)Density matrix describes the
"state" of an average particle in an ensemble. It can not describe the state of
an individual particle in an ensemble in detail; 2) Entanglement is a property
of the wave function of a quantum particle(such as an molecule in a liquid NMR
sample). Separability of the density matrix can not be used to measure the
entanglement of mixed ensemble; 3)The evolution of states in bulk-ensemble NMR
quantum computation is quantum mechanical; 4) The coefficient before the
effective pure state density matrix, $\epsilon$, is an measure of the
simultaneity of the molecules in an ensemble. It reflects the intensity of the
NMR signal and has no significance in quantifying the entanglement in the bulk
ensemble NMR system. We conclude that the liquid NMR quantum computation is
genuine, not just classical simulations.

</DOC>
<DOC>
<DOCNO> 116663 </DOCNO>
Rhythmos, Diathige, Trope


  It is argued that properties of Democritus' atoms parallel those of volume
forms in differential geometry. This kind of atoms has not "size" of finite
magnitude.
  -----
 Se arguye que las propiedades de los atomos de Democrito son paralelas a las
de sus formas de volumen en geometria diferencial. Este tipo de atomos no tiene
tamanno de magnitud finita.

</DOC>
<DOC>
<DOCNO> 9222 </DOCNO>
Spintronics and Quantum Dots for Quantum Computing and Quantum


  Control over electron-spin states, such as coherent manipulation, filtering
and measurement promises access to new technologies in conventional as well as
in quantum computation and quantum communication. We review our proposal of
using electron spins in quantum confined structures as qubits and discuss the
requirements for implementing a quantum computer. We describe several
realizations of one- and two-qubit gates and of the read-in and read-out tasks.
We discuss recently proposed schemes for using a single quantum dot as
spin-filter and spin-memory device. Considering electronic EPR pairs needed for
quantum communication we show that their spin entanglement can be detected in
mesoscopic transport measurements using metallic as well as superconducting
leads attached to the dots.

</DOC>
<DOC>
<DOCNO> 70177 </DOCNO>
Neutrinos produced by ultrahigh-energy photons at high red shift


  Some of the proposed explanations for the origin of ultrahigh-energy cosmic
rays invoke new sources of energetic photons (e.g., topological defects, relic
particles, etc.). At high red shift, when the cosmic microwave background has a
higher temperature but the radio background is low, the ultrahigh-energy
photons can generate neutrinos through pair-production of muons and pions.
Neutrinos produced at high red shift by slowly evolving sources can be
detected. Rapidly evolving sources of photons can be ruled out based on the
existing upper limit on the neutrino flux.

</DOC>
<DOC>
<DOCNO> 9924 </DOCNO>
The doping dependence of T* - what is the real high-Tc phase diagram?


  Underdoped high-Tc superconductors are frequently characterised by a
temperature, T*, below which the normal-state pseudogap opens. Two different
"phase diagrams" based on the doping (p) dependence of T* are currently
considered: one where T* falls to zero at a critical doping state and the other
where T* merges with Tc in the overdoped region. By examining the temperature
dependence of the NMR Knight shift and relaxation rate, entropy, resistivity,
infrared conductivity, Raman scattering, ARPES and tunnelling data it is
concluded that the second scenario is not at all supported. Neither can one
distinguish a small and a large pseudogap as is often done. T* is an energy
scale which falls abruptly to zero at p=0.19.

</DOC>
<DOC>
<DOCNO> 70498 </DOCNO>
The 3D Yang-Mills system. Lecture notes on the Karabali-Nair theory


  The Schroedinger functional treatment of 2+1 D Yang-Mills theory is
recapitulated, in great calculational detail, by following three papers of
Karabali, Kim and Nair in 1998/99. The notes include the Hermitean WZW model,
regularization, the functional Hamiltonian, the string tension and the magnetic
mass problem of 4D hot gluons.

</DOC>
<DOC>
<DOCNO> 69369 </DOCNO>
Soft Double-Diffractive Higgs Production at Hadron Colliders


  We evaluate the non-perturbative contribution to the double-diffractive
production of the Higgs boson, which arises due to the QCD scale anomaly if the
mass of the Higgs M_H is smaller than the mass of the top quark M_T, M_H < M_T.
The cross section appears to be larger than expected from perturbative
calculations; we find \sigma_H = 0.019 - 0.14 pbarn at the Tevatron energy, and
\sigma_H = 0.01 - 0.27 pbarn at the energy of the LHC.

</DOC>
<DOC>
<DOCNO> 123163 </DOCNO>
Starbursts in multiple galaxy mergers


  We numerically investigate stellar and gaseous dynamical evolution of mergers
between five identical late-type disk galaxies with the special emphasis on
star formation history and chemical evolution of multiple galaxy mergers. We
found that multiple encounter and merging can trigger repetitive massive
starbursts (typically $\sim$ 100 $M_{\odot}$ ${\rm yr}^{-1}$) owing to the
strong tidal disturbance and the resultant gaseous dissipation during merging.
The magnitude of the starburst is found to depend on initial virial ratio
(i.e., the ratio of total kinematical energy to total potential energy) such
that the maximum star formation rate is larger for the merger with smaller
virial ratio. Furthermore we found that the time interval between the epochs of
the triggered starbursts is longer for the merger with the larger virial ratio.
The remnant of a multiple galaxy merger with massive starbursts is found to
have metal-poor gaseous halo that is formed by tidal stripping during the
merging. We accordingly suggest that metal-poor gaseous halo in a field
elliptical galaxy is a fossil record of the past multiple merging events for
the galaxy.

</DOC>
<DOC>
<DOCNO> 150830 </DOCNO>
T-duality and Actions for Non-BPS D-branes


  We employ T-duality to restrict the tachyon dependence of effective actions
for non-BPS D-branes. For the Born-Infeld part the criteria of T-duality and
supersymmetry are satisfied by a simple extension of the D-brane Born-Infeld
action.

</DOC>
<DOC>
<DOCNO> 13028 </DOCNO>
Numerical study of persistence in systems with absorbing states


  Extensive Monte Carlo simulations are performed in order to evaluate both the
local ($\theta_{l}$) and global ($\theta_{g}$) persistence exponents in the
Ziff-Gulari-Barshad (ZGB) (Phy. Rev. Lett. {\bf 56}, 2553, (1986)) irreversible
reaction model. In two dimensions and for the second-order irreversible phase
transition (IPT) we find, that both the local and the global persistence
exhibit power-law behavior with a crossover between two different time regimes.
On the other hand, at the first-order IPT, characteristic of the ZGB, active
sites are short lived and the persistence decays more abruptly, not being clear
whether it shows power law behavior or not. In order to analyze universality
issues, we have also studied another model with absorbing states, the contact
process, and evaluated the local persistence exponent in dimensions from 1 to
4. A striking apparent {\it super-universality} is reported: the local
persistence exponent seems to coincide in both one and two dimensional systems.

</DOC>
<DOC>
<DOCNO> 178795 </DOCNO>
Jet Quenching and Azimuthal Anisotropy of Large $p_T$ Spectra in


  Parton energy loss inside a dense medium leads to the suppression of large
$p_T$ hadrons and can also cause azimuthal anisotropy of hadron spectra at
large transverse momentum in non-central high-energy heavy-ion collisions. Such
azimuthal anisotropy is studied qualitatively in a parton model for heavy-ion
collisions at the RHIC energies. The coefficient $v_2(p_T)$ of the elliptic
anisotropy at large $p_T$ is found to be very sensitive to parton energy loss.
It decreases slowly with $p_T$ contrary to its low $p_T$ behavior where $v_2$
increases very rapidly with $p_T$. The turning point signals the onset of
contributions of hard processes and the magnitude of parton energy loss. The
centrality dependence of $v_2(p_T)$ is shown to be sensitive to both size and
density dependence of the parton energy loss and the later can also be studied
via variation of the colliding energy. The anisotropy coefficient
$v_2/\epsilon$ normalized by the spatial ellipticity $\epsilon$ is found to
decrease significantly toward semi-peripheral collisions, differing from the
hydrodynamic results for low $p_T$ hadrons. Constrained by the existing WA98
experimental data at the SPS energy on parton energy loss, both hadron spectra
suppression and azimuthal anisotropy at high $p_T$ are predicted to vanish for
$b>$7-8 fm in $Au+Au$ collisions at $\sqrt{s}=$130-200 GeV when the hadron
rapidity density per unit area of the initial overlapped region is less than
what is achieved in the central $Pb+Pb$ collisions at the SPS energy.

</DOC>
<DOC>
<DOCNO> 99750 </DOCNO>
Geometrical Issues for the 3-dim Quantum Euclidean Space


  We briefly describe our application of a version of noncommutative
differential geometry to the 3-dim quantum space covariant under the quantum
group of rotations $SO_q(3)$ and sketch how this might be used to determine the
correct physical interpretation of the geometrical observables.

</DOC>
<DOC>
<DOCNO> 12065 </DOCNO>
Reply on the Comment cond-mat/0008209 about "Solution of Classical


  In their Comment, Park, Park and Kim claimed that the approach devised in our
work Phys.Rev.Lett. {\bf 83}, 5214 (1999) reproduces the correct long-time
behaviour of the density and correlation functions of the model under
consideration because of the {\it irrelevance} of the quartic term. Park,Park
and Kim also claimed that the approach devised in Phys.Rev.Lett. {\bf 83}, 5214
(1999) is a traditional Hartree-Fock approach.
  In this Reply we argue that the results obtained with our approach are in
agreement (also the subdominant corrections) with previous numerical
calculations and are therefore beyond traditional approximative
 (e.g. Hartree-Fock) schemes. Such a striking agreement cannot, in our opinion,
be explained only by the {\it eventual} irrelevance of a quartic term.

</DOC>
<DOC>
<DOCNO> 101141 </DOCNO>
Conference matrices and unimodular lattices


  Conference matrices are used to define complex structures on real vector
spaces. Certain lattices in these spaces become modules for rings of quadratic
integers. Multiplication of these lattices by non-principal ideals yields
simple constructions of further lattices including the Leech lattice.

</DOC>
<DOC>
<DOCNO> 122659 </DOCNO>
The 1997 hard state outburst of the X-ray transient GS 1354-64 / BW Cir


  We present observations of the 1997 outburst of the X-ray transient GS
1354-64 (BW Cir) at X-ray, optical and, for the first time, radio wavelengths;
this includes upper limits to the linear and circular polarisation of the radio
data. The X-ray outburst was unusual in that the source remained in the
low/hard X-ray state throughout; the X-ray peak was also preceded by at least
one optical outburst, suggesting that it was an `outside-in' outburst - similar
to those observed in dwarf novae systems, although possibly taking place on a
viscous timescale in this case. It therefore indicates that the optical
emission was not dominated by the reprocessing of X-rays but that instead we
see the instability directly. While the radio source was too faint to detect
any extended structure, spectral analysis of the radio data and a comparison
with other similar systems suggests that mass ejections, probably in the form
of a jet, took place and that the emitted synchrotron spectrum may have
extended as far as infrared wavelengths. Finally, we compare this 1997 outburst
of GS 1354-64 with possible previous outbursts and also with other hard state
objects, both transient and persistent. It appears that a set of
characteristics -- such as a weak, flat spectrum radio jet, a mHz QPO
increasing in frequency, a surprisingly high optical:X-ray luminosity ratio and
the observed optical peak preceding the X-ray peak -- may be common to all hard
state X-ray transients.

</DOC>
<DOC>
<DOCNO> 80872 </DOCNO>
Full QCD Light Hadron Spectrum and Quark Masses: Final Results from


  We present the final results of the CP-PACS calculation of the light hadron
spectrum and quark masses with two flavors of dynamical quarks. Simulations are
made with a renormalization-group improved gauge action and a mean-field
improved clover quark action for sea quark masses corresponding to $m_{\rm
PS}/m_{\rm V} \approx 0.8$--0.6 and the lattice spacing $a=0.22$--0.11 fm. For
the meson spectrum in the continuum limit a clearly improved agreement with
experiment is observed compared to the quenched case, demonstrating the
importance of sea quark effects. For light quark masses we obtain
$m_{ud}^{\bar{MS}}(2GeV)=3.44^{+0.14}_{-0.22}$ MeV and
$m_s^{\bar{MS}}(2GeV)=88^{+4}_{-6}$ MeV ($K$-input) and
$m_s^{\bar{MS}}(2GeV)=90^{+5}_{-11}$ MeV ($\phi$-input), which are reduced by
about 25% compared to the values in quenched QCD.

</DOC>
<DOC>
<DOCNO> 8163 </DOCNO>
Elastic Properties of the Vortex Lattice for a Superconducting Film of


  In this paper we investigate the elastic properties of the vortex lattice for
a superconducting film of finite thickness. We derive an analytic expression
for the compression modulus. The shear modulus is evaluated numerically by
using both the Pearl interaction potential, valid in the limit of very thin
film, and a potential for films of arbitrary thickness. A comparative study of
the shear moduli is carried out.

</DOC>
<DOC>
<DOCNO> 12459 </DOCNO>
Generalized Lanczos Algorithm for Variational Quantum Monte Carlo


  We show that the standard Lanczos algorithm can be efficiently implemented
statistically and self consistently improved, using the stochastic reconfigurat
ion method, which has been recently introduced to stabilize the Monte Carlo
sign problem instability. With this scheme a few Lanczos steps over a given
variational wavefunction are possible even for large size as a particular case
of a more general and more accurate technique that allows to obtain lower
variational energies. This method has been tested extensively for a strongly
correlated model like the t-J model. With the standard Lanczos technique it is
possible to compute any kind of correlation functions, with no particular
computational effort. By using that the variance $<H^2>-<H>^2$ is zero for an
exact eigenstate, we show that the approach to the exact solution with few
Lanczos ite rations is indeed possible even for $\sim 100$ electrons for
reasonably good initial wavefunctions.The variational stochastic
reconfiguration technique presented here allows in general a many-parameter
energy optimization of any computable many-body wavefunction, including for
inst ance generic long range Jastrow factors and arbitrary site dependent
orbital determinants. This scheme improves further the accuracy of the
calculation, especially for long distance correlation functions.

</DOC>
<DOC>
<DOCNO> 102848 </DOCNO>
On surfaces with $p_g=q=2$ and non-birational bicanonical map


  This paper is devoted to the classification of irregular surfaces of general
type with $p_g=q=2$ and non birational bicanonical map. The main result is
that, if $S$ is such a surface and if $S$ is minimal with no pencil of curves
of genus 2, then $S$ is a double cover of a principally polarized abelian
surface $(A,\Theta)$, with $\Theta$ irreducible. The double cover $S\to A$ is
branched along a divisor $B\in |2\Theta|$, having at most double points and so
$K_S^2=4$.

</DOC>
<DOC>
<DOCNO> 116496 </DOCNO>
An Underpinning for Space Time


  We argue, that from a background pre space-time Zero Point Field, physical
space-time emerges on averaging over unphysical Compton scales.

</DOC>
<DOC>
<DOCNO> 100519 </DOCNO>
Wess-Zumino-Witten model on elliptic curves at the critical level


  We construct a Gaudin type lattice model as the Wess-Zumino-Witten model on
elliptic curves at the critical level. Bethe eigenvectors are obtained by the
bosonisation technique.

</DOC>
<DOC>
<DOCNO> 10478 </DOCNO>
Magneto-elastic excitations in spin-Peierls systems


  Within the random phase approximation to the spin-Peierls transition two
parameter regimes of phonon softening and hardening are present.
Magneto-elastic excitations are discussed in detail for phonons coupled to the
exactly solvable model of XY spin chains for both regimes, leading to a
modified interpretation of the 30 cm$^{-1}$ mode in CuGeO$_3$. Frustrated
Heisenberg chains coupled to phonons satisfactory describe the pre-transitional
quasi-elastic scattering in CuGeO$_3$. A real space interpretation of the
quasi-elastic scattering is given justifying effective Ising model approaches.

</DOC>
<DOC>
<DOCNO> 70482 </DOCNO>
Self-Interacting Dark Matter from the Hidden Heterotic-String Sector


  It has been suggested recently that self-interacting dark matter fits better
the observational characteristics of galaxy dynamics. We propose that the
self-interacting dark matter is composed from the glueballs of the hidden
sector non-Abelian gauge group, while the hidden matter states exist in
vector-like representation and decouple from the light spectrum. It is shown
that these glueballs are semi-stable with the life-time larger than the present
age of the Universe, if their mass is 1 GeV or less. The constraint on their
abundance today suggests that the energy was stored in the hidden sector soon
after inflation. This imposes an upper limit on the reheating temperature. We
further study the naturalness of this scenario in the context of the
free-fermionic string models and point out a class of such models where the
self-interacting dark matter from the hidden sector is indeed plausible.

</DOC>
<DOC>
<DOCNO> 100142 </DOCNO>
Phase space observables and isotypic spaces


  We give necessary and sufficient conditions for the set of Neumark
projections of a countable set of phase space observable to constitute a
resolution of the identity, and we give a criteria for a phase space observable
to be informationally complete. The results will be applied to the phase space
observables arising from an irreducible representation of the Heisenberg group.

</DOC>
<DOC>
<DOCNO> 121257 </DOCNO>
Age-metallicity relation and Chemical evolution of the LMC from UVES


  We report on the first high-resolution spectroscopy of 10 giants in LMC
Globular Clusters in a wide age range, obtained with the newly commissioned
spectrograph UVES at VLT UT2. These observations are used to derive oxygen and
iron content of these clusters, and the abundances are then used to cast a more
precise view, not only on the age-metallicity relation in the LMC, but also on
the chemical evolution of this dwarf irregular galaxy.

</DOC>
<DOC>
<DOCNO> 118900 </DOCNO>
A TiO study of the black-hole binary GRO J0422+32 in a very low state


  We present 53 simultaneous photometric (I band) and spectroscopic (6900-9500
Angstroms) observations of J0422+32, taken during December 1997. From these we
determine that J0422+32 was in its lowest state yet observed, at
I=20.44+/-0.08. Using relative spectrophotometry, we show that it is possible
to correct very accurately for telluric absorption. Following this, we use the
TiO bands at 7055 Angstroms and 7589 Angstroms for a radial velocity study and
thereby obtain a semi-amplitude of 378+/-16kms-1, which yields
f(M)=1.191+/-0.021M_solar and q=9.0+2.2-2.7, consistent with previous
observations. We further demonstrate that this little explored method is very
powerful for such systems. We also determine a new orbital ephemeris of
HJD=2450274.4156+/-0.0009 + 0.2121600+/-0.0000002E.
  We see some evidence for an ellipsoidal modulation, from which we determine
the orbital inclination of J0422+32 to be less than 45 degrees. We therefore
calculate a minimum mass for the primary of 2.22M_solar, consistent with a
black hole, but not necessarily the super-massive one proposed by Beekman et al
(1997). We obtain an M4-5 spectral type for the secondary star and determine
that the secondary contributes 38+/-2% of the flux that we observe from
J0422+32 over the range 6950-8400 Angstroms. From this we calculate the
distance to the system to be 1.39+/-0.15kpc.

</DOC>
<DOC>
<DOCNO> 80674 </DOCNO>
Center vortex model for the infrared sector of Yang-Mills theory -


  A definition of the Pontryagin index for SU(2) center vortex world-surfaces
composed of plaquettes on a hypercubic lattice is constructed. It is used to
evaluate the topological susceptibility in a previously defined random surface
model for vortices, the parameters of which have been fixed such as to
reproduce the confinement properties of SU(2) Yang-Mills theory. A prediction
for the topological susceptibility is obtained which is compatible with
measurements of this quantity in lattice Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 13199 </DOCNO>
Vertices and Vortices in High Tc Superconductors


  Two different aspects of high T_c superconductivity is studied in two
independent parts of this thesis. In the first part we study Landau's Fermi
liquid theory and nearly antiferromagnetic Fermi liquid theory (NAFL) in 2D. We
that inflection points on the Fermi surface provide 2D singularities which have
to be taken seriously in Fermi liquid considerations. We then focus on
self-consistency of NAFL in calculations base on Eliashberg formalism. We
calculate the first vertex correction for an optimally doped system and show
that it is of the same order of magnitude as the bare vertex. Migdal's theorem
is therefore not valid and the Eliashberg formalism is not applicable. The same
conclusion is obtained even after inclusion of the quasiparticle residue Z to
the calculation. In part II of the thesis, we establish a method to study
vortex lattice properties of d-wave superconductors based on a generalization
of the London model. The method has the advantage of simplicity as well as
having very few free parameters (one at most) compared to other methods. The
generalized London free energy is obtained from an s-d mixing Ginsburg-Landau
free energy and also from the microscopic theory of Gorkov. The generalized
London equation is found to be non-analytic at very low temperatures because of
the nodes on the superconducting gap. We present the results of our
calculations for some measurable quantities, such as the vortex lattice
geometry and the effective penetration depth (as defined in muSR experiments)
with comparison to experiments.

</DOC>
<DOC>
<DOCNO> 119278 </DOCNO>
Numerical Simulations in Cosmology I: Methods


  This lecture gives a short introduction to different methods used in
cosmology. The focus is on major features of N-body simulations: equations,
main numerical techniques, effects of resolution, and methods of halo
identification.

</DOC>
<DOC>
<DOCNO> 102225 </DOCNO>
A note on group actions on subfactors


  We construct approximately inner actions of discrete amenable groups on
strongly amenable subfactors of type II_1 with given invariants, and obtain
classification results under some conditions. We also study the lifting of the
relative \chi group.

</DOC>
<DOC>
<DOCNO> 71074 </DOCNO>
Mass Spectrum and the Nature of Neutrinos


  Taking as input the best fit solar neutrino anomaly description, MSW LMA, and
the tritium beta decay results we estimate the allowed range of neutrino masses
independently of their nature. Adding the present bound on the effective
neutrino mass coming from neutrinoless double beta decay, we narrow this range
for Majorana neutrinos. We complete the discussion by considering future
perspectives on determining the neutrino masses, when the oscillation data will
be improved and the next experiments on $(\beta\beta)_{0\nu}$ and $^3H$ decay
give new bounds or obtain concrete life-times or distortions in the energy
distribution.

</DOC>
<DOC>
<DOCNO> 68920 </DOCNO>
A comparative study of the D0 neural-network analysis of the top quark


  A simpler neural-network approach is presented for the analysis of the top
quark non-leptonic decay channel in events of the D0 Collaboration. Results for
the top quark signal are comparable to those found by the D0 Collaboration by a
more elaborate handling of the event information used as input to the neural
network.

</DOC>
<DOC>
<DOCNO> 118008 </DOCNO>
The Lx-T, Lx-sigma and sigma-T relations for groups and clusters of


  While in the hierarchical model of structure formation, groups of galaxies
are believed to be the scaled-down version of clusters of galaxies, a
similarity breaking in the fundamental laws may occur on the group scale,
reflecting a transition between galaxy-dominated and intracluster medium
dominated properties. In this paper, we present an extensive study of the
relations between the X-ray luminosity (Lx), the temperature (T) of hot diffuse
gas and the velocity dispersion (sigma) of galaxies for groups and clusters of
galaxies, based on the largest sample of 66 groups and 274 clusters drawn from
literature. Our best fit Lx-T and Lx-sigma relations for groups read Lx propto
T^(5.57+-1.79) propto sigma^(2.35+-0.21), which deviates remarkably from those
for clusters: Lx propto T^(2.79+-0.08) propto sigma^(5.30+-0.21). The
significance of these correlations have been justified by both the
co-consistency test and the Kendall's tau statistics. We have thus confirmed
the existence of similarity breaking in the Lx-T and Lx-sigma relations between
groups and clusters as claimed in previous work, although the best fit sigma-T
relations remain roughly the same in both systems: sigma propto T^0.64.
Alternatively, the significant disagreement between the observationally fitted
Lx-T and Lx-sigma relations for groups and those expected from a perfect
hydrostatic equilibrium hypothesis indicates that the X-ray emission of
individual galaxies and the non-gravitational heating must play a potentially
important role in the dynamical evolution of groups. Therefore, reasonable
caution should be exercised in the cosmological applications of the dynamical
properties of groups.

</DOC>
<DOC>
<DOCNO> 84636 </DOCNO>
Plane-fronted waves in metric-affine gravity


  We study plane-fronted electrovacuum waves in metric-affine gravity theories
(MAG) with cosmological constant. Their field strengths are, on the
gravitational side, curvature $R_{\alpha}{}^{\beta}$, nonmetricity
$Q_{\alpha\beta}$, torsion $T^{\alpha}$ and, on the matter side, the
electromagnetic field strength $F$. Our starting point is the work by
Ozsv\'ath, Robinson, and R\'ozga on type N gravitational fields in general
relativity as coupled to null electromagnetic fields.

</DOC>
<DOC>
<DOCNO> 151830 </DOCNO>
On Link Invariants and Topological String Amplitudes


  We explicitly show that the new polynomial invariants for knots, upto nine
crossings, agree with the Ooguri-Vafa conjecture relating Chern-Simons gauge
theory to topological string theory on the resolution of the conifold.

</DOC>
<DOC>
<DOCNO> 118416 </DOCNO>
A High-Eccentricity Low-Mass Companion to HD 89744


  HD 89744 is an F7 V star with mass 1.4 M, effective temperature 6166 K, age
2.0 Gy and metallicity [Fe/H]= 0.18. The radial velocity of the star has been
monitored with the AFOE spectrograph at the Whipple Observatory since 1996, and
evidence has been found for a low mass companion. The data were complemented by
additional data from the Hamilton spectrograph at Lick Observatory during the
companion's periastron passage in fall 1999. As a result, we have determined
the star's orbital wobble to have period P = 256 d, orbital amplitude K = 257
m/s, and eccentricity e = 0.7. From the stellar mass we infer that the
companion has minimum mass m2 sin i = 7.2 MJup in an orbit with semi-major axis
a2 = 0.88 AU. The eccentricity of the orbit, among the highest known for
extra-solar planets, continues the trend that extra-solar planets with
semi-major axes greater than about 0.15 AU tend to have much higher
eccentricities than are found in our solar system. The high metallicity of the
parent star reinforces the trend that parent stars of extra-solar planets tend
to have high metallicity

</DOC>
<DOC>
<DOCNO> 69287 </DOCNO>
Constraints on the Mass and Mixing of the 4th Generation Quark From


  We investigate the $\epsilon^{\prime} /\epsilon$ for $K\to \pi\pi$ in a
sequential fourth generation model. By giving the basic formulae for
$\epsilon^{\prime}/\epsilon$ in this model, we analyze the numerical results
which are dependent of $m_{t^{\prime}}$ and imaginary part of the fourth CKM
factor, ${Im}V^{*}_{t^{'}s}V_{t^{'}d}$ (or $V^{*}_{t^{'}s}V_{t^{'}d}$ and the
fourth generation CKM matrix phase $\theta$). We find that, unlike the SM, when
taking the central values of all parameters for $\epsilon^{\prime}/\epsilon$,
the values of $\epsilon^{\prime}/ \epsilon$ can easily fit to the current
experimental data for all values of hadronic matrix elements estimated from
various approaches. Also, we show that the experimental values of
$\epsilon^{\prime}/\epsilon$ and rare K decays can provide a strong constraint
on both mass and mixing of the fourth generation quark. When taking the values
of hadronic matrix elements from the lattice or 1/N expansion calculations, a
large region of the up-type quark mass $m_{t^{\prime}}$ is excluded.

</DOC>
<DOC>
<DOCNO> 71590 </DOCNO>
Toward a Neutrino Mass Matrix


  One may identify the general properties of the neutrino mass matrix by
generating many random mass matrices and testing them against the results of
the neutrino experiments.

</DOC>
<DOC>
<DOCNO> 69776 </DOCNO>
Conformally symmetric massive discrete fields


  Conformal symmetry is taken as an attribute of theories of massless fields in
manifolds with specific dimensionalities. This paper shows that this is not an
absolute truth; it is a consequence of the mathematical representation used for
the physical interactions. It introduces a new kind of representation where the
propagation of massive (invariant mass) and massless interactions are unifiedly
described by a single conformally symmetric Green's function. Sources and
fields are treated at a same footing, symmetrically, as discrete fields - the
fields in this new representation - fields defined with support on straight
lines embedded in a (3+1)-Minkowski manifold. The discrete field turns out to
be a point in phase space. It is finite everywhere. With a finite number of
degrees of freedom it does not share the well known problems faced by the
standard continuous formalism which can be retrieved from the discrete one by
an integration over a hypersurface. The passage from discrete to continuous
fields illuminates the physical meaning and origins of their properties and
problems. The price for having massive discrete field with conformal symmetry
is of hiding its mass and time-like velocity behind its non-constant
proper-time.

</DOC>
<DOC>
<DOCNO> 122678 </DOCNO>
Substructure in clusters containing wide-angle tailed radio galaxies. I.


  We present new redshifts and positions for 635 galaxies in nine rich clusters
containing Wide-Angle Tailed (WAT) radio galaxies. Combined with existing data,
we now have a sample of 18 WAT-containing clusters with more than 10 redshifts.
This sample contains a substantial portion of the WAT clusters in the VLA 20 cm
survey of Abell clusters, including 75% of WAT clusters in the complete survey
(z<=0.09), and 20% of WAT clusters with z>0.09. It is a representative sample
which should not contain biases other than selection by radio morphology. We
graphically present the new data using histograms and sky maps. A
semi-automated procedure is used to search for emission lines in the spectra in
order to add and verify galaxy redshifts. We find that the average apparent
fraction of emission line galaxies is about 9% in both the clusters and the
field. We investigate the magnitude completeness of our redshift surveys with
CCD data for a test case, Abell 690. This case indicates that our galaxy target
lists are deeper than the detection limit of a typical MX exposure, and they
are 82% complete down to R=19.0. The importance of the uniformity of the
placement of fibers on targets is posited, and we evaluate this in our
datasets. We find some cases of non-uniformities which may influence dynamical
analyses. A second paper will use this database to look for correlations
between the WAT radio morphology and the cluster's dynamical state.

</DOC>
<DOC>
<DOCNO> 70040 </DOCNO>
The $\gamma \gamma \to A^0 A^0$ process at a $\gamma \gamma $ Collider


  The helicity amplitudes for the process $\gamma \gamma \to A^0 A^0$ are
studied to 1-loop order in the minimal SUSY (MSSM) model, where $A^0$ is the
CP-odd Higgs particle.
  Simple exact analytic formulae are obtained, in terms of the $C_0$ and $D_0$
Passarino-Veltman functions; in spite of the fact that the loop-diagrams often
involve different particles running along their sides. For a usual mSUGRA set
of parameters, $\sigma (\gamma \gamma \to A^0 A^0) \sim (0.1-0.2)\rm fb $ is
expected. If SUSY is realized in Nature, these expressions should be useful for
understanding the Higgs sector.

</DOC>
<DOC>
<DOCNO> 11530 </DOCNO>
Josephson currents through spin-active interfaces


  The Josephson coupling of two isotropic s-wave superconductors through a
small, magnetically active junction is studied. This is done as a function of
junction transparency and of the degree of spin-mixing occurring in the
barrier. In the tunneling limit, the critical current shows an anomalous 1/T
temperature dependence at low temperatures and for certain magnetic
realizations of the junction. The behavior of the Josephson current is governed
by Andreev bound states appearing within the superconducting gap and the
position of these states in energy is tunable with the magnetic properties of
the barrier. This study is done using the equilibrium part of the
quasiclassical Zaitsev-Millis-Rainer-Sauls boundary condition for spin-active
interfaces and a general solution of the boundary condition is found. This
solution is a generalization of the one recently presented by Eschrig [M.
Eschrig, Phys. Rev B 61, 9061 (2000)] for spin-conserving interfaces and allows
an effective treatment of the problem of a superconductor in proximity to a
magnetically active material.

</DOC>
<DOC>
<DOCNO> 11790 </DOCNO>
Elementary excitations in one-dimensional spin-orbital models: neutral


  We study, both numerically and variationally, the interplay between different
types of elementary excitations in the model of a spin chain with anisotropic
spin-orbit coupling, in the vicinity of the "dimer line" with an exactly known
dimerized ground state. Our variational treatment is found to be in a
qualitative agreement with the exact diagonalization results. Soliton pairs are
shown to be the lowest excitations only in a very narrow region of the phase
diagram near the dimer line, and the phase transitions are always governed by
magnon-type excitations which can be viewed as soliton-antisoliton bound
states. It is shown that when the anisotropy exceeds certain critical value, a
new phase boundary appears. In the doped model on the dimer line, the exact
elementary charge excitation is shown to be a hole bound to a soliton. Bound
states of those "charged solitons" are studied; exact solutions for N-hole
bound states are presented.

</DOC>
<DOC>
<DOCNO> 8603 </DOCNO>
Strong, Ultra-narrow Peaks of Longitudinal and Hall Resistances in the


  With unusually slow and high-resolution sweeps of magnetic field, strong,
ultra-narrow (width down to $100 {\rm \mu T}$) resistance peaks are observed in
the regime of breakdown of the quantum Hall effect. The peaks are dependent on
the directions and even the history of magnetic field sweeps, indicating the
involvement of a very slow physical process. Such a process and the sharp peaks
are, however, not predicted by existing theories. We also find a clear
connection between the resistance peaks and nuclear spin polarization.

</DOC>
<DOC>
<DOCNO> 80772 </DOCNO>
Parallel tempering and decorrelation of topological charge in full QCD


  The improvement of simulations of QCD with dynamical Wilson fermions by
combining the Hybrid Monte Carlo algorithm with parallel tempering is studied
on $10^4$ and $12^4$ lattices. As an indicator for decorrelation the
topological charge is used.

</DOC>
<DOC>
<DOCNO> 150713 </DOCNO>
SU(2) WZW D-branes and their non-commutative geometry from DBI action


  Using properties of the DBI action we find D-branes on $S^3$ of the radius
$Q_5$ corresponding to the conjugacy classes of SU(2). The branes are stable
due to nonzero 2-form NSNS background. In the limit of large $Q_5$ the dynamics
of branes is governed by the non-commutative Yang-Mills theory. The results
partially overlap with those obtained in the recent paper hep-th/0003037.

</DOC>
<DOC>
<DOCNO> 9660 </DOCNO>
On the formation of Wigner molecules in small quantum dots


  It was recently argued that in small quantum dots the electrons could
crystallize at much higher densities than in the infinite two-dimensional
electron gas. We compare predictions that the onset of spin polarization and
the formation of Wigner molecules occurs at a density parameter $r_s\approx 4
a_B^*$ to the results of a straight-forward diagonalization of the Hamiltonian
matrix.

</DOC>
<DOC>
<DOCNO> 101187 </DOCNO>
Automorphic forms, fake monster algebras and hyperbolic reflection


  We construct 2 families of automorphic forms related to twisted fake monster
algebras and calculate their Fourier expansions. This gives a new proof of
their denominator identities and shows that they define automorphic forms of
singular weight. We also obtain new infinite product identities which are the
denominator identities of generalized Kac-Moody superalgebras. Finally we
describe the reflection groups of the root lattices of these algebras.

</DOC>
<DOC>
<DOCNO> 100470 </DOCNO>
Focal Loci of Algebraic Varieties I


  The focal locus $\Sigma_X$ of an affine variety $X$ is roughly speaking the
(projective) closure of the set of points $O$ for which there is a smooth point
$x \in X$ and a circle with centre $O$ passing through $x$ which osculates $X$
in $x$. Algebraic geometry interprets the focal locus as the branching locus of
the endpoint map $\epsilon$ between the Euclidean normal bundle $N_X$ and the
projective ambient space ($\epsilon$ sends the normal vector $O-x$ to its
endpoint $O$), and in this paper we address two general problems :
  1) Characterize the "degenerate" case where the focal locus is not a
hypersurface
  2) Calculate, in the case where $\Sigma_X$ is a hypersurface, its degree
(with multiplicity)

</DOC>
<DOC>
<DOCNO> 100819 </DOCNO>
A signed generalization of the Bernoulli-Laplace diffusion model


  We bound the rate of convergence to stationarity for a signed generalization
of the Bernoulli-Laplace diffusion model; this signed generalization is a
Markov chain on the homogeneous space (Z_2 \wr S_n) / (S_r \times S_{n-r}).
Specifically, for r not too far from n/2, we determine that, to first order in
n, 1/4 n \log n steps are both necessary and sufficient for total variation
distance to become small. Moreover, for r not too far from n/2, we show that
our signed generalization also exhibits the ``cutoff phenomenon.''

</DOC>
<DOC>
<DOCNO> 8742 </DOCNO>
The Anderson prescription for surfaces and impurities


  We test the Anderson prescription [1], a BCS formalism for describing
superconductivity in inhomogeneous systems, and compare results with those
obtained from the Bogoliubov-de Gennes formalism, using the attractive Hubbard
model with surfaces and nonmagnetic impurities. The Anderson approach captures
the essential features of the spatial variation of the gap parameter and
electron density around a surface or an impurity over a wide range of
parameters. It breaks down, however, in the strong-coupling regime for a weak
impurity potential.
  [1] P. W. Anderson, J. Phys. Chem. Solids 11, 26 (1959).

</DOC>
<DOC>
<DOCNO> 85079 </DOCNO>
No-go theorem for false vacuum black holes


  We study the possibility of non-singular black hole solutions in the theory
of general relativity coupled to a non-linear scalar field with a positive
potential possessing two minima: a `false vacuum' with positive energy and a
`true vacuum' with zero energy. Assuming that the scalar field starts at the
false vacuum at the origin and comes to the true vacuum at spatial infinity, we
prove a no-go theorem by extending a no-hair theorem to the black hole
interior: no smooth solutions exist which interpolate between the local de
Sitter solution near the origin and the asymptotic Schwarzschild solution
through a regular event horizon or several horizons.

</DOC>
<DOC>
<DOCNO> 150538 </DOCNO>
Fundamental Extended Objects for Chern-Simons Supergravity


  We propose a class of models in which extended objects are introduced in
Chern-Simons supergravity in such a way that those objects appear on the same
footing as the target space. This is motivated by the idea that branes are
already first quantized object, so that it is desirable to have a formalism
that treats branes and their target space in a similar fashion. Accordingly,
our models describe interacting branes, as gauge systems for supergroups. We
also consider the case in which those objects have boundaries, and discuss
possible links to superstring theory and/or M-theory, by studying the fermionic
kappa-symmetry of the action.

</DOC>
<DOC>
<DOCNO> 39965 </DOCNO>
Measurement of W-pair production in e+e- collisions at 189GeV


  The production of W-pairs is analysed in a data sample collected by ALEPH at
a mean centre-of-mass energy of 188.6 GeV, corresponding to an integrated
luminosity of 174.2 pb^-1. Cross sections are given for different topologies of
W decays into leptons or hadrons. Combining all final states and assuming
Standard Model branching fractions, the total W-pair cross section is measured
to be 15.71 +- 0.34 (stat) +- 0.18 (syst) pb. Using also the W-pair data
samples collected by ALEPH at lower centre-of-mass energies, the decay
branching fraction of the W boson into hadrons is measured to be BR (W >
hadrons) = 66.97 +- 0.65 (stat) +- 0.32 (syst) %, allowing a determination of
the CKM matrix element |V(cs)|= 0.951 +- 0.030 (stat) +- 0.015 (syst).

</DOC>
<DOC>
<DOCNO> 99272 </DOCNO>
HyperK\"ahler Potentials via Finite-Dimensional Quotients


  It is known that nilpotent orbits in a complex simple Lie algebra admit
hyperK\"ahler metrics with a single function that is a global potential for
each of the K\"ahler structures (a hyperK\"ahler potential). In an earlier
paper the authors showed that nilpotent orbits in classical Lie algebras can be
constructed as finite-dimensional hyperK\"ahler quotient of a flat vector
space. This paper uses that quotient construction to compute hyperK\"ahler
potentials explicitly for orbits of elements with small Jordan blocks. It is
seen that the K\"ahler potentials of Biquard and Gauduchon for SL(n)-orbits of
elements with X^2=0, are in fact hyperK\"ahler potentials.

</DOC>
<DOC>
<DOCNO> 100748 </DOCNO>
On the Topological Interpretation of Gravitational Anomalies


  We consider the mixed gravitational-Yang-Mills anomaly as the coupling
between the $K$-theory and $K$-homology of a $C^*$-algebra crossed product. The
index theorem of Connes-Moscovici allows to compute the Chern character of the
$K$-cycle by local formulae involving connections and curvatures. It gives a
topological interpretation to the anomaly, in the sense of noncommutative
algebras.

</DOC>
<DOC>
<DOCNO> 150919 </DOCNO>
Quantum mechanics with time-dependent parameters


  Smooth composite bundles provide the adequate geometric description of
classical mechanics with time-dependent parameters. We show that the Berry's
phase phenomenon is described in terms of connections on composite Hilbert
space bundles.

</DOC>
<DOC>
<DOCNO> 120812 </DOCNO>
Dust Grain Size Distributions and Extinction in the Milky Way, LMC, and


  We construct size distributions for carbonaceous and silicate grain
populations in different regions of the Milky Way, LMC, and SMC. The size
distributions include sufficient very small carbonaceous grains (including
polycyclic aromatic hydrocarbon molecules) to account for the observed infrared
and microwave emission from the diffuse interstellar medium. Our distributions
reproduce the observed extinction of starlight, which varies depending upon the
interstellar environment through which the light travels. As shown by Cardelli,
Clayton & Mathis in 1989, these variations can be roughly parameterized by the
ratio of visual extinction to reddening, R_V. We adopt a fairly simple
functional form for the size distribution, characterized by several parameters.
We tabulate these parameters for various combinations of values for R_V and
b_C, the C abundance in very small grains. We also find size distributions for
the line of sight to HD 210121, and for sightlines in the LMC and SMC. For
several size distributions, we evaluate the albedo and scattering asymmetry
parameter, and present model extinction curves extending beyond the Lyman
limit.

</DOC>
<DOC>
<DOCNO> 116683 </DOCNO>
Increased Efficiency of Quantum State Estimation Using Non-Separable


  We address the "major open problem" of evaluating how much increased
efficiency in estimation is possible using non-separable, as opposed to
separable, measurements of N copies of m-level quantum systems. First, we study
the six cases m = 2, N = 2,...,7 by computing the the 3 x 3 Fisher information
matrices for the corresponding optimal measurements recently devised by Vidal
et al (quant-ph/9812068) for N = 2,...,7. We obtain simple polynomial
expressions for the ("Gill-Massar") traces of the products of the inverse of
the quantum Helstrom information matrix and these Fisher information matrices.
The six traces all have minima of 2 N -1 in the pure state limit, while for
separable measurements (quant-ph/9902063), the traces can equal N, but not
exceed it. Then, the result of an analysis for m = 3, N = 2 leads us to
conjecture that for optimal measurements for all m and N, the "Gill-Massar
trace" achieves a minimum of (2N-1)(m-1) in the pure state limit.

</DOC>
<DOC>
<DOCNO> 117793 </DOCNO>
Colour Change Measurements of Gravitational Microlensing Events by Using


  Detecting colour changes of a gravitational microlensing event induced by the
limb-darkened extended source effect is important to obtain useful information
both about the lens and source star. However, precise measurements of the
colour changes are hampered by blending, which also causes colour changes of
the event. In this paper, we show that although the colour change measured from
the subtracted image by using the recently developed photometric method of the
``difference image analysis'' (DIA) differs from the colour change measured by
using the conventional method based on the extraction of the individual source
stars' point spread functions, the curve of the colour changes (colour curve)
constructed by using the DIA method enables one to obtain the same information
about the lens and source star, but with significantly reduced uncertainties
due to the absence of blending. We investigate the patterns of the DIA colour
curves for both single lens and binary lens events by constructing colour
change maps.

</DOC>
<DOC>
<DOCNO> 120145 </DOCNO>
New star clusters projected close to the Galactic Centre


  We carried out a systematic search for new star clusters in a field of
5$^{\circ} \times5^{\circ}$ centred close to the Galactic Nucleus using the
infrared JHK$_s$ 2MASS Survey archive. In addition we searched for embedded
clusters in the directions of HII regions and dark clouds for
$|\ell|\le4^{\circ}$. As a result we present a list of 58 IR star clusters or
candidates. We provide positions, sizes and reddening estimated from 100 $\mu$m
dust emission. Their angular distribution together with previously catalogued
objects in the region and possible relation with star forming complexes are
also discussed.

</DOC>
<DOC>
<DOCNO> 11137 </DOCNO>
Nonlinear quantum evolution with maximal entropy production


  We derive a well-behaved nonlinear extension of the non-relativistic
Liouville-von Neumann dynamics driven by maximal entropy production with
conservation of energy and probability. The pure state limit reduces to the
usual Schroedinger evolution, while mixtures evolve towards maximum entropy
equilibrium states with canonical-like probability distributions on energy
eigenstates. The linear, near-equilibrium limit is found to amount to an
essentially exponential relaxation to thermal equilibrium; a few elementary
examples are given. In addition, the modified dynamics is invariant under the
time-independent symmetry group of the hamiltonian, and also invariant under
the special Galilei group provided the conservation of total momentum is
accounted for as well. Similar extensions can be generated for, e.g.,
nonextensive systems better described by a Tsallis q-entropy.

</DOC>
<DOC>
<DOCNO> 101825 </DOCNO>
Exact triangles in Seiberg-Witten Floer theory. Part III: proof of


  This is the third part of the work on the exact triangles. We construct chain
homomorphisms and show exactness of the resulting sequence.

</DOC>
<DOC>
<DOCNO> 10302 </DOCNO>
The Transition in the Two-Dimensional Step Model: A Kosterlitz-Thouless


  Evidence for a Kosterlitz-Thouless transition in the 2D step model is
obtained from Monte Carlo determinations of the helicity modulus. It is argued
that the free energy of a single vortex at the center of the system depends
logarithmically on the system size in spite of the fact that the spin
interaction is not harmonic for small differences in the spin angles. We
conclude that this is the reason for the Kosterlitz-Thouless transition in the
2D step model and that the harmonic spin interaction not is a necessary
requirement.

</DOC>
<DOC>
<DOCNO> 9948 </DOCNO>
Conjecture on the Interlacing of Zeros in Complex Sturm-Liouville


  The zeros of the eigenfunctions of self-adjoint Sturm-Liouville eigenvalue
problems interlace. For these problems interlacing is crucial for completeness.
For the complex Sturm-Liouville problem associated with the Schrodinger
equation for a non-Hermitian PT-symmetric Hamiltonian, completeness and
interlacing of zeros have never been examined. This paper reports a numerical
study of the Sturm-Liouville problems for three complex potentials, the large-N
limit of a -(ix)^N potential, a quasi-exactly-solvable -x^4 potential, and an
ix^3 potential. In all cases the complex zeros of the eigenfunctions exhibit a
similar pattern of interlacing and it is conjectured that this pattern is
universal. Understanding this pattern could provide insight into whether the
eigenfunctions of complex Sturm-Liouville problems form a complete set.

</DOC>
<DOC>
<DOCNO> 80795 </DOCNO>
Incorporating Chiral Symmetry and Heavy Quark Theory in Extrapolations


  We extrapolate lattice calculations of electric charge radii of the spin-1/2
baryon octet to the physical regime. The extrapolation procedure incorporates
chiral perturbation theory and heavy quark effective theory in the appropriate
limits. In particular, this procedure includes the non-analytic, logarithmic
terms from pion loops. The electric charge radii of the nucleons and $\Sigma^-$
obtained from the chiral extrapolations agree well with experimental data. We
make predictions for the charge radii of the remaining baryons in anticipation
of future experimental measurements.

</DOC>
<DOC>
<DOCNO> 10688 </DOCNO>
No well-defined remnant Fermi surface in Sr2CuO2Cl2


  In angle-resolved photoelectron spectra of the antiferromagnetic insulators
Ca2CuO2Cl2 and Sr2CuO2Cl2 a sharp drop of the spectral intensity of the
lowest-lying band is observed along a line in k space equivalent to the Fermi
surface of the optimally doped high-temperature superconductors. This was
interpreted as a signature of the existence of a remnant Fermi surface in the
insulating phase of the high-temperature superconductors. In this paper it is
shown that the drop of the spectral intensity is not related to the spectral
function but is a consequence of the electron-photon matrix element

</DOC>
<DOC>
<DOCNO> 122104 </DOCNO>
A New Spin on Galactic Dust


  We present a new puzzle involving Galactic microwave emission and attempt to
resolve it. On one hand, a cross-correlation analysis of the WHAM H-alpha map
with the Tenerife 10 and 15 GHz maps shows that the well-known DIRBE correlated
microwave emission cannot be dominated by free-free emission. On the other
hand, recent high resolution observations in the 8-10 GHz range with the Green
Bank 140 ft telescope by Finkbeiner et al. failed to find the corresponding 8
sigma signal that would be expected in the simplest spinning dust models. So
what physical mechanism is causing this ubiquitous dust-correlated emission? We
argue for a model predicting that spinning dust is the culprit after all, but
that the corresponding small grains are well correlated with the larger grains
seen at 100 micron only on large angular scales. In support of this grain
segregation model, we find the best spinning dust template to involve higher
frequency maps in the range 12-60 micron, where emission from transiently
heated small grains is important. Upcoming CMB experiments such as ground-based
interferometers, MAP and Planck LFI with high resolution at low frequencies
should allow a definitive test of this model.

</DOC>
<DOC>
<DOCNO> 152455 </DOCNO>
The method of direct expansions of Feynman integrals


  The universal method of expansion of integrals is suggested. It allows in
particular to derive the threshold expansion of Feynman integrals.

</DOC>
<DOC>
<DOCNO> 100869 </DOCNO>
Partial Dynamical Systems and the KMS Condition


  Given a countably infinite 0-1 matrix A without identically zero rows, let
O_A be the Cuntz-Krieger algebra recently introduced by the authors and T_A be
the Toeplitz extension of O_A, once the latter is seen as a Cuntz-Pimsner
algebra, as recently shown by Szymanski. We study the KMS equilibrium states of
C*-dynamical systems based on O_A and T_A, with dynamics satisfying
\sigma_t(s_x) = N_x^{it} s_x for the canonical generating partial isometries
s_x and arbitrary real numbers N_x > 1. The KMS_\beta states on both O_A and
T_A are completely characterized for certain values of the inverse temperature
\beta, according to the position of \beta relative to three critical values,
defined to be the abscissa of convergence of certain Dirichlet series
associated to A and the N(x). Our results for O_A are derived from those for
T_A by virtue of the former being a covariant quotient of the latter. When the
matrix A is finite, these results give theorems of Olesen and Pedersen for O_n
and of Enomoto, Fujii and Watatani for O_A as particular cases.

</DOC>
<DOC>
<DOCNO> 12860 </DOCNO>
Phase separation in La$_{0.5}$Ca$_{0.5}$MnO$_3$ doped with 1% $^{119}$Sn


  1% $^{119}$Sn-doped La$_{0.5}$Ca$_{0.5}$MnO$_3$ was studied by M\"ossbauer
spectroscopy, magnetic moment and resistivity measurements. The M\"ossbauer
spectra below the charge-ordering temperature are explained with ferromagnetic
(FM), antiferromagnetic (AF), and ferromagnetic spin cluster (CL) components.
The magnetic and thermal hystereses of the relative intensities of the
components observed in the M\"ossbauer spectra, and of the bulk properties such
as magnetic moment and electrical resistivity, in the temperature range 125-185
K, are characteristic of phase equilibrium in a first-order transition, i.e. of
phase separation in the system below the charge-ordering (CO) transition. The
cluster component displays a significant hyperfine field up to $\sim 125$ K.
Above this temperature it exhibits superparamagnetism, becoming the dominant
component above the charge-ordering transition. These results are discussed in
the framework of recent investigations of the manganite system with other
techniques which also show phase separation.

</DOC>
<DOC>
<DOCNO> 13500 </DOCNO>
Critical geometry of two-dimensional passive scalar turbulence


  Passive scalars advected by a magnetically driven two-dimensional turbulent
flow are analyzed using methods of statistical topography. The passive tracer
concentration is interpreted as the height of a random surface and the scaling
properties of its contour loops are analyzed. Various exponents that describe
the loop ensemble are measured and compared to a scaling theory. This leads to
a geometrical criterion of intermittency of scalar fluctuations.

</DOC>
<DOC>
<DOCNO> 39904 </DOCNO>
Determination of the QCD Coupling $\alpha_s$


  Theoretical basics and experimental determinations of the coupling parameter
of the Strong Interaction, $\alpha_s$, are reviewed. The world average value of
$\alpha_s$, expressed at the energy scale of the rest mass of the $Z^0$ boson,
is determined from analyses which are based on complete NNLO perturbative QCD.
The result is $\alpha_s (M_Z) = 0.1184 \pm 0.0031$. No significant deviations
or systematic biases of subsamples of experimental results are found. From the
observed energy dependence of $\alpha_s$, which is in excellent agreement with
the expectations of QCD, the number of colour degrees of freedom can be
constrained to $N_c = 3.03 \pm 0.12$.

</DOC>
<DOC>
<DOCNO> 11550 </DOCNO>
Out-of-equilibrium thermodynamic relations in systems with aging and


  The experimental time scale dependence of thermodynamic relations in
out-of-equilibrium systems with aging phenomena is investigated theoretically
by using only aging properties of the two-time correlation functions and the
generalized fluctuation-dissipation theorem (FDT). We show that there are two
experimental time regimes characterized by different thermal properties. In the
first regime where the waiting time is much longer than the measurement time,
the principle of minimum work holds even though a system is out of equilibrium.
In the second regime where both the measurement time and the waiting time are
long, the thermal properties are completely different from properties in
equilibrium. For the single-correlation-scale systems such as $p$-spin
spherical spin-glasses, contrary to a fundamental assumption of thermodynamics,
the work done in an infinitely slow operation depends on the path of change of
the external field even when the waiting time is infinite. On the other hand,
for the multi-correlation-scale systems such as Sherrington-Kirkpatrick model,
the work done in an infinitely slow operation is independent of the path. Our
results imply that in order to describe thermodynamic properties of systems
with aging it is essential to consider the experimental time scales and history
of a system as a state variable is necessary.

</DOC>
<DOC>
<DOCNO> 100179 </DOCNO>
Characterization of Cyclic and Separating Vectors and Application to an


  This paper generalizes the results obtained in an earlier paper
(math.OA/0003087) for finite factors to infinite but still semifinite factors.
First we give a characterization of cyclic and separating vectors for infinite
semifinite factors in terms of operators associated with this vector and being
affiliated with the factor. Further we show how this operator generates the
modular objects of the given cyclic and separating vector generalizing an idea
of Kadison and Ringrose. With the help of these results we can show that the
second simple class of solutions for the inverse problem constructed in
math.OA/0003087 never exists in infinite semifinite factors. Finally we give a
classification of the solutions of the inverse problem in the case of modular
operators having pure point spectrum, completely analoguous to the finite case.

</DOC>
<DOC>
<DOCNO> 117245 </DOCNO>
Theory of self phase-locked optical parametric oscillators


  The plane-wave dynamics of 3*omega => (2*omega, omega) subharmonic optical
parametric oscillators containing a second harmonic generator of the idler wave
omega is analyzed analytically by using the meanfield approximation and
numerically by taking into account the field propagation inside the media. The
resonant Chi(2):Chi(2) cascaded second-order nonlinearities induce a mutual
injection-locking of the signal and idler waves that leads to coherent self
phase-locking of the pump and subharmonic waves, freezing the phase diffusion
noise. In case of signal-and-idler resonant devices, largely detuned
sub-threshold states occur due to a subcritical bifurcation, broadening out the
self-locking frequency range to a few cavity linewidths.

</DOC>
<DOC>
<DOCNO> 120709 </DOCNO>
Constraints on Cosmological Anisotropy out to z=1 from Supernovae Ia


  A combined sample of 79 high and low redshift supernovae Ia (SNe) is used to
set constraints on the degree of anisotropy in the Universe out to $z\simeq1$.
First we derive the global most probable values of matter density $\Omega_M $,
the cosmological constant $\Omega_\Lambda $, and the Hubble constant $H_0$, and
find them to be consistent with the published results from the two data sets of
Riess et al. 1998 (R98) and Perlmutter et al. 1999 (P99). We then examine the
Hubble diagram (HD, i.e., the luminosity-redshift relation) in different
directions on the sky by utilising spherical harmonic expansion. In particular,
via the analysis of the dipole anisotropy, we divide the sky into the two
hemispheres that yield the most discrepant of the three cosmological
parameters, and the scatter $\chi^2_{\rm HD}$ in each case. The most discrepant
values roughly move along the locus $-4\Omega_M +3 \Omega_{\Lambda} = 1$ (cf.
P99), but by no more than $\Delta \approx 2.5$ along this line. For a perfect
FRW universe, Monte Carlo realizations that mimic the current set of SNe yield
values higher than the measured $\Delta$ in $\sim 1/5$ of the cases. We discuss
implications for the validity of the Cosmological Principle, and possible
calibration problems in the SNe data sets.

</DOC>
<DOC>
<DOCNO> 100833 </DOCNO>
Output-input stability and minimum-phase nonlinear systems


  This paper introduces and studies the notion of output-input stability, which
represents a variant of the minimum-phase property for general smooth nonlinear
control systems. The definition of output-input stability does not rely on a
particular choice of coordinates in which the system takes a normal form or on
the computation of zero dynamics. In the spirit of the ``input-to-state
stability'' philosophy, it requires the state and the input of the system to be
bounded by a suitable function of the output and derivatives of the output,
modulo a decaying term depending on initial conditions. The class of
output-input stable systems thus defined includes all affine systems in global
normal form whose internal dynamics are input-to-state stable and also all
left-invertible linear systems whose transmission zeros have negative real
parts. As an application, we explain how the new concept enables one to develop
a natural extension to nonlinear systems of a basic result from linear adaptive
control.

</DOC>
<DOC>
<DOCNO> 9005 </DOCNO>
A conjectured scenario for order-parameter fluctuations in spin glasses


  We study order-parameter fluctuations (OPF) in disordered systems by
considering the behavior of some recently introduced paramaters $G,G_c$ which
have proven very useful to locate phase transitions. We prove that both
parameters G (for disconnected overlap disorder averages) and $G_c$ (for
connected disorder averages) take the respective universal values 1/3 and 13/31
in the $T\to 0$ limit for any {\em finite} volume provided the ground state is
{\em unique} and there is no gap in the ground state local-field distributions,
conditions which are met in generic spin-glass models with continuous couplings
and no gap at zero coupling. This makes $G,G_c$ ideal parameters to locate
phase transitions in disordered systems much alike the Binder cumulant is for
ordered systems. We check our results by exactly computing OPF in a simple
example of uncoupled spins in the presence of random fields and the
one-dimensional Ising spin glass. At finite temperatures, we discuss in which
conditions the value 1/3 for G may be recovered by conjecturing different
scenarios depending on whether OPF are finite or vanish in the infinite-volume
limit. In particular, we discuss replica equivalence and its natural
consequence $\lim_{V\to\infty}G(V,T)=1/3$ when OPF are finite. As an example of
a model where OPF vanish and replica equivalence does not give information
about G we study the Sherrington-Kirkpatrick spherical spin-glass model by
doing numerical simulations for small sizes. Again we find results compatible
with G=1/3 in the spin-glass phase.

</DOC>
<DOC>
<DOCNO> 118261 </DOCNO>
The Extreme Compact Starburst in MRK 273


  Images of neutral Hydrogen 21cm absorption and radio continuum emission at
1.4 GHz from Mrk 273 were made using the Very Long Baseline Array and Very
Large Array. These images reveal a gas disk associated with the northern
nuclear region with a diameter of 0.5'' (370 pc), at an inclination angle of
53deg. The radio continuum emission is composed of a diffuse component plus a
number of compact sources. This morphology resembles those of nearby, lower
luminosity starburst galaxies. These images provide strong support for the
hypothesis that the luminosity of the northern source is dominated by an
extreme compact starburst. The HI 21cm absorption shows an east-west gradient
in velocity of 450 km/s across 0.3'' (220 pc), implying an enclosed mass of 2e9
M_solar, comparable to the molecular gas mass. The brightest of the compact
sources may indicate radio emission from an active nucleus (AGN), but this
source contributes only 3.8% to the total flux density of the northern nuclear
region. The HI 21cm absorption toward the southeast radio nucleus suggests
infall at 200 km/s on scales < 40 pc, and the southwest near IR nucleus is not
detected in high resolution radio continuum images.

</DOC>
<DOC>
<DOCNO> 170717 </DOCNO>
Modified relative entropy of entanglement for multi-party systems


  We present the modified relative entropy of entanglement for multi-party
systems by a given relative density matrix which is spanned by a linear
combination of the direct products of so-called basis of relative density
matrices and reduced density matrices for every party. For three qubit system
in a pure state we derive out the explicit and closed expression of our
relative density matrix which is a function of the components of the state
vector of three qubits. Through computing the modified relative entropy of
entanglement of some important and interesting examples, we display the main
behaviors and elementary properties of the modified relative entropy of
entanglement and compare it with the generalized entanglement of formation.
Moreover, we also propose an assistant, as the upper bound, of the modified
relative entropy of entanglement.

</DOC>
<DOC>
<DOCNO> 85171 </DOCNO>
Hawking radiation and Hawking flux from spherical reduction


  Using heat kernel techniques we show that the relation between Hawking
temperature and radiation flux known from Einstein gravity in D dimensions can
be reproduced from the spherically reduced action. A recent controversy
regarding the D=2 anomaly for that case is discussed. The generalized effective
Polyakov action in the presence of a dilaton field is presented.

</DOC>
<DOC>
<DOCNO> 151144 </DOCNO>
Five-Brane BPS States in Heterotic M-Theory


  We present explicit methods for computing the discriminant curves and the
associated Kodaira type fiber degeneracies of elliptically fibered Calabi-Yau
threefolds. These methods are applied to a specific three-family, SU(5) grand
unified theory of particle physics within the context of Heterotic M-Theory. It
is demonstrated that there is always a region of moduli space where a bulk
space five-brane is wrapped on a pure fiber in the Calabi-Yau threefold.
Restricting the discussion to the smooth parts of the discriminant curve, we
explore the properties of the N=2 BPS supermultiplets that arise on the
worldvolume of this five-brane due to the degeneration of the elliptic fiber.
The associated degenerating M membranes are shown to project to string
junctions in the base space. We use string junction techniques to explicitly
compute the light BPS hyper- and vector multiplet spectrum for each Kodaira
type fiber near the smooth part of the discriminant curve in the SU(5) GUT
theory.

</DOC>
<DOC>
<DOCNO> 70409 </DOCNO>
Nuclear dependence asymmetries in direct photon production


  We study the nuclear dependences of high-$p_T$ jet cross sections in one
photon and one jet production in proton-nucleus collisions. We find that there
exist asymmetries between the outgoing jets and photons. A convincing reason
responsible for those asymmetries are demonstrated in perturbative QCD.
Significant nuclear enhancements are also found in the inclusive jet cross
sections.

</DOC>
<DOC>
<DOCNO> 122438 </DOCNO>
The European Photon Imaging Camera on XMM-Newton: The MOS Cameras


  The EPIC focal plane imaging spectrometers on XMM-Newton use CCDs to record
the images and spectra of celestial X-ray sources focused by the three X-ray
mirrors. There is one camera at the focus of each mirror; two of the cameras
contain seven MOS CCDs, while the third uses twelve PN CCDs, defining a
circular field of view of 30 arcmin diameter in each case. The CCDs were
specially developed for EPIC, and combine high quality imaging with spectral
resolution close to the Fano limit. A filter wheel carrying three kinds of
X-ray transparent light blocking filter, a fully closed, and a fully open
position, is fitted to each EPIC instrument. The CCDs are cooled passively and
are under full closed loop thermal control. A radio-active source is fitted for
internal calibration. Data are processed on-board to save telemetry by removing
cosmic ray tracks, and generating X-ray event files; a variety of different
instrument modes are available to increase the dynamic range of the instrument
and to enable fast timing. The instruments were calibrated using laboratory
X-ray beams, and synchrotron generated monochromatic X-ray beams before launch;
in-orbit calibration makes use of a variety of celestial X-ray targets. The
current calibration is better than 10% over the entire energy range of 0.2 to
10 keV. All three instruments survived launch and are performing nominally in
orbit. In particular full field-of-view coverage is available, all electronic
modes work, and the energy resolution is close to pre-launch values. Radiation
damage is well within pre-launch predictions and does not yet impact on the
energy resolution. The scientific results from EPIC amply fulfil pre-launch
expectations.

</DOC>
<DOC>
<DOCNO> 151305 </DOCNO>
Implications of N=1 Superconformal Symmetry for Chiral Fields


  The requirements of N=1 superconformal invariance for the correlation
functions of chiral superfields are analysed. Complete expressions are found
for the three point function for the general spin case and for the four point
function for scalar superfields for \sum q_i=3 where q_i is the scale dimension
for the i'th superfield and is related to the U(1) R-charge. In the latter case
the relevant Ward identities reduce to eight differential equations for four
functions of u,v which are invariants when the superconformal symmetry is
reduced to the usual conformal group. The differential equations have a general
solution given by four linearly independent expressions involving a two
variable generalisation of the hypergeometric function. By considering the
behaviour under permutations, or crossing symmetry, the chiral four point
function is shown to be determined up to a single overall constant. The results
are in accord with the supersymmetric operator product expansion.

</DOC>
<DOC>
<DOCNO> 69506 </DOCNO>
Electroweak baryogenesis at and after preheating: What's the difference?


  Two recent scenarios of preheating-related baryogenesis are compared within
the framework of Abelian Higgs model in (1+1) dimensions. It is shown that they
shift baryon number in opposite directions. Once both scenarios can realize
simultaneously as overlapped stages of the same physical process, even the sign
of net generated asymmetry becomes dependent on initial parameters.

</DOC>
<DOC>
<DOCNO> 80924 </DOCNO>
Percolation and the existence of a soft phase in the classical


  We present the results of a numerical investigation of percolation properties
in a version of the classical Heisenberg model. In particular we study the
percolation properties of the subsets of the lattice corresponding to
equatorial strips of the target manifold ${\cal S}^2$. As shown by us several
years ago, this is relevant for the existence of a massless phase of the model.
Our investigation yields strong evidence that such a massless phase does indeed
exist. It is further shown that this result implies lack of asymptotic freedom
in the massive continuum limit. A heuristic estimate of the transition
temperature is given which is consistent with the numerical data.

</DOC>
<DOC>
<DOCNO> 83449 </DOCNO>
A Lambda-Calculus with letrec, case, constructors and non-determinism


  A non-deterministic call-by-need lambda-calculus \calc with case,
constructors, letrec and a (non-deterministic) erratic choice, based on
rewriting rules is investigated. A standard reduction is defined as a variant
of left-most outermost reduction. The semantics is defined by contextual
equivalence of expressions instead of using $\alpha\beta(\eta)$-equivalence. It
is shown that several program transformations are correct, for example all
(deterministic) rules of the calculus, and in addition the rules for garbage
collection, removing indirections and unique copy.
  This shows that the combination of a context lemma and a meta-rewriting on
reductions using complete sets of commuting (forking, resp.) diagrams is a
useful and successful method for providing a semantics of a functional
programming language and proving correctness of program transformations.

</DOC>
<DOC>
<DOCNO> 40296 </DOCNO>
Review of Recent Searches for Rare and Forbidden Dilepton Decays of


  I briefly review the results of recent searches for flavor-changing neutral
current and lepton-flavor and lepton-number violating decays of D+, Ds, and D0
mesons (and their antiparticles) into modes containing muons and electrons. The
primary focus is the results from Fermilab charm hadroproduction experiment
E791. E791 examined 24 pi,l,l and K,l,l decay modes of D+ and Ds and l+l- decay
modes of D0. Limits presented by E791 for 22 rare and forbidden dilepton decays
of D mesons were more stringent than those obtained from previous searches, or
else were the first reported.

</DOC>
<DOC>
<DOCNO> 101684 </DOCNO>
Wonderful blowups associated to group actions


  A group action on a smooth variety provides it with the natural
stratification by irreducible components of the fixed point sets of arbitrary
subgroups. We show that the corresponding maximal wonderful blowup in the sense
of MacPherson-Procesi has only abelian stabilizers. The result is inspired by
the abelianization algorithm of Batyrev.

</DOC>
<DOC>
<DOCNO> 83101 </DOCNO>
Computing Circumscriptive Databases by Integer Programming: Revisited


  In this paper, we consider a method of computing minimal models in
circumscription using integer programming in propositional logic and
first-order logic with domain closure axioms and unique name axioms. This kind
of treatment is very important since this enable to apply various technique
developed in operations research to nonmonotonic reasoning.
  Nerode et al. (1995) are the first to propose a method of computing
circumscription using integer programming. They claimed their method was
correct for circumscription with fixed predicate, but we show that their method
does not correctly reflect their claim. We show a correct method of computing
all the minimal models not only with fixed predicates but also with varied
predicates and we extend our method to compute prioritized circumscription as
well.

</DOC>
<DOC>
<DOCNO> 116716 </DOCNO>
What can biology bestow to quantum mechanics?


  The biological hierarchy and the differences between living and non-living
matter are considered from the standpoint of quantum mechanics.

</DOC>
<DOC>
<DOCNO> 152240 </DOCNO>
Center Vortices in Continuum Yang-Mills Theory


  The properties of center vortices are discussed within continuum Yang-Mills
theory. By starting from the lattice theory and carefully performing the
continuum limit the gauge potential of center vortices is obtained and the
continuum analog of the maximal center gauge fixing is extracted. It is shown,
that the Pontryagin index of center vortices is given by their
self-intersection number, which vanishes unless the center vortices host
magnetic monpoles, which make the vortex sheets non-oriented.

</DOC>
<DOC>
<DOCNO> 69057 </DOCNO>
Doubly heavy baryons Omega_QQ' vs. Xi_QQ' in sum rules of NRQCD


  In the framework of two-point sum rules of NRQCD, the masses and couplings of
doubly heavy baryons to the corresponding quark currents are evaluated with
account of coulomb-like corrections in the system of doubly heavy diquark as
well as the contribution of nonperturbative terms determined by the quark,
gluon, mixed condensates and the product of gluon and quark condensates. The
introduction of nonzero light quark mass destroys the factorization of baryon
and diquark correlators even at the perturbative level and provides the better
convergency of sum rules. We estimate the difference M_Omega - M_Xi = 100+/- 10
MeV. The ratio of baryonic constants |Z_Omega|^2/|Z_Xi|^2 is equal to 1.3+/-0.2
indicating the violation of SU(3) flavor symmetry for the doubly heavy baryons.

</DOC>
<DOC>
<DOCNO> 101818 </DOCNO>
Hyperbolic Dehn surgery on geometrically infinite 3-manifolds


  In this paper we extend Thurston's hyperbolic Dehn surgery theorem to a class
of geometrically infinite hyperbolic 3-manifolds. As an application we prove a
modest density theorem for Kleinian groups. We also discuss hyperbolic Dehn
surgery on geometrically finite hypebolic cone-manifolds.

</DOC>
<DOC>
<DOCNO> 178682 </DOCNO>
Phenomenological Evidence for Gluon Depletion in pA Collisions


  The data of J/psi suppression at large x_F in pA collisions are used to infer
the existence of gluon depletion as the projectile proton traverses the
nucleus. The modification of the gluon distribution is studied by use of a
convolution equation whose non-perturbative splitting function is determined
phenomenologically. The depletion factor at x_1=0.8 is found to be about 25% at
A=100.

</DOC>
<DOC>
<DOCNO> 8393 </DOCNO>
Special Analytical Solutions of the Schr\"odinger Equation for 2 and 3


  We found that the two-dimensional Schr\"odinger equation for 3 electrons in
an homogeneous magnetic field (perpendicular to the plane) and a parabolic
scalar confinement potential (frequency $\omega_0$) has exact analytical
solutions in the limit, where the expectation value of the center of mass
vector $\bf R$ is small compared with the average distance between the
electrons. These analytical solutions exist only for certain discrete values of
the effective frequency $\tilde \omega=\sqrt{\omega_o^2 + ({\omega_c \over 2}
)^2}$. Further, for finite external fields, the total angular momenta must be
M_L=3 m with m=integer, and spins have to be parallel. The analytically
solvable states are always cusp states, and take the components of higher
Landau levels into account. These special analytical solutions for 3 particles
and the previously published exact analytical solutions for 2 particles can be
written in an unified form. These formulae, when {\em ad hoc} generalized to N
coordinates, can be discussed as an ansatz for the wave function of the
N-particle system. This ansatz fulfills the following demands: it is exact for
two particles and for 3 particles in the limit of small $\bf R$ and for the
solvable external fields, and it is an eigenfuncton of the total orbital
angular momentum. The Laughlin functions are special cases of this ansatz for
infinite solvable fields and equal pair- angular- momenta.

</DOC>
<DOC>
<DOCNO> 122512 </DOCNO>
The DIRTY Model II: Self-Consistent Treatment of Dust Heating and


  In this paper and a companion paper we present the DIRTY model, a Monte Carlo
radiative transfer code, self-consistently including dust heating and emission,
and accounting for the effects of the transient heating of small grains. The
code is completely general; the density structure of the dust, the number and
type of heating sources, and their geometric configurations can be specified
arbitrarily within the model space. Source photons are tracked through the
scattering and absorbing medium using Monte Carlo techniques and the effects of
multiple scattering are included. The dust scattering, absorbing, and emitting
properties are calculated from realistic dust models derived by fitting
observed extinction curves in Local Group galaxies including the Magellanic
Clouds and the Milky Way. The dust temperature and the emitted dust spectrum
are calculated self consistently from the absorbed energy including the effects
of temperature fluctuations in small grains. Dust self-absorption is also
accounted for, allowing the treatment of high optical depths, by treating
photons emitted by the dust as an additional heating source and adopting an
iterative radiative transfer scheme. As an illustrative case, we apply the
DIRTY radiative transfer code to starburst galaxies wherein the heating sources
are derived from stellar evolutionary synthesis models. Within the context of
the starburst model, we examine the dependence of the UV to FIR SED, dust
temperatures, and dust masses predicted by DIRTY on variations of the input
parameters.

</DOC>
<DOC>
<DOCNO> 9825 </DOCNO>
Comment on "Spin relaxation in quantum Hall systems"


  W. Apel and Yu.A. Bychkov have recently considered the spin relaxation in a
2D quantum Hall system for the filling factor close to unity [PRL v.82, 3324
(1999)]. The authors considered only one spin flip mechanism (direct
spin-phonon coupling) among several possible spin-orbit related ones and came
to the conclusion that the spin relaxation time due to this mechanism is quite
short: around $10^{-10}$ s at B=10 T (for GaAs). This time is much shorter than
the typical time ($10^{-5}$ s) obtained earlier by D. Frenkel while considering
the spin relaxation of 2D electrons in a quantizing magnetic field without the
Coulomb interaction and for the same spin-phonon coupling. I show that the
authors' conclusion about the value of the spin-flip time is wrong and have
deduced the correct time which is by several orders of magnitude longer. I also
discuss the admixture mechanism of the spin-orbit interaction.

</DOC>
<DOC>
<DOCNO> 70386 </DOCNO>
Ultra-high energy cosmic neutrinos


  Several cosmologically distant astrophysical sources may produce ultra-high
energy cosmic neutrinos (E > 10^6 GeV) of all flavors above the atmospheric
neutrino background. I study the effects of vacuum neutrino flavor mixing on
this cosmic neutrino flux. Prospects for observations of these ultra-high
energy cosmic neutrinos in large underwater/ice neutrino telescopes are also
briefly discussed.

</DOC>
<DOC>
<DOCNO> 120896 </DOCNO>
A near-IR [Fe II] line imaging survey of supernova remnants in M33


  We report on the first near-IR [Fe II] line imaging survey of extragalactic
 SNRs.
 Observations of a sample of 42 objects drawn from an optically-selected
catalogue of SNRs in M33 provide evidence for a wide range in the [Fe II] 1.644
microns luminosities. This can be understood as being primarily due to
variations in the chemical abundances and density of the local ISM, although
shock conditions may also play a significant role. We briefly discuss how these
results may be used to better calibrate the supernova rate of star-forming
galaxies.

</DOC>
<DOC>
<DOCNO> 100530 </DOCNO>
On semi-infinite cohomology of finite dimensional algebras


  We show that semi-infinite cohomology of a finite dimensional graded algebra
(satisfying some additional requirements) are a particular case of a general
categorical construction. The motivating example is provided by small quantum
groups at a root of unity.

</DOC>
<DOC>
<DOCNO> 118942 </DOCNO>
On the mass of moderately rotating strange stars in the MIT bag model


  We compute the maximum mass of moderately rotating strange stars as a
function of the strange quark mass, of the QCD coupling constant, $\alpha_c$,
and of the bag constant (vacuum energy density), $B$, in the MIT bag model of
quark matter with lowest order quark-gluon interactions. For a fixed value of
$B$, the maximum stellar mass depends only weakly on $\alpha_c$, and is
independent of this coupling in the limit of massless quarks. However, if it is
the value of the chemical potential of quark matter at zero pressure which is
held constant, for example at the value corresponding to the stability limit of
nucleons against conversion to quark matter, the maximum mass of the strange
star is higher by up to 25% for $\alpha_c=0.6$, than for non-interacting
quarks, and this may be relevant in the discussion of kHz QPO sources. The
maximum mass of a non-rotating strange star could be sufficiently high to allow
an orbital frequency as low as 1.0 kHz in the marginally stable orbit. However,
for all $\alpha_c<0.6$, the stellar mass cannot exceed $2.6M_\odot$ at any
rotational period $\ge1.6 $ms.

</DOC>
<DOC>
<DOCNO> 152399 </DOCNO>
Electric-Magnetic Duality in QED Effective Action


  Recently we have obtained a non-perturbative but convergent series expression
of the one loop effective action of QED, and discussed the renormalization of
the effective action. In this paper we establish the electric-magnetic duality
in the quantum effective action.

</DOC>
<DOC>
<DOCNO> 72041 </DOCNO>
Comment about pion electro-production and the axial form factors


  The claim by Haberzettl (Phys.Rev.Lett.85 (2000) 3576) that the axial form
factor of the nucleon cannot be accessed through threshold pion
electroproduction is unfounded.

</DOC>
<DOC>
<DOCNO> 84621 </DOCNO>
Semiclassical Cosmological Perturbations Generated during Inflation


  Environment interaction may induce stochastic semiclassical dynamics in open
quantum systems. In the gravitational context, stress-energy fluctuations of
quantum matter fields give rise to a stochastic behaviour in the spacetime
geometry. Einstein-Langevin equation is a suitable tool to take these effects
into account when addressing the back-reaction problem in semiclassical
gravity. We analyze within this framework the generation of gravitational
fluctuations during inflation, which are of great interest for large-scale
structure formation in cosmology.

</DOC>
<DOC>
<DOCNO> 170351 </DOCNO>
Why do Bell experiments?


  Experiments over three decades have been unable to demonstrate weak
nonlocality in the sense of Bell unambiguously, without loopholes. The last
important loophole remaining is the detection loophole, which is being tackled
by at least three experimental groups. This letter counters five common beliefs
about Bell experiments, and presents alternative scenarios for future
developments.

</DOC>
<DOC>
<DOCNO> 150551 </DOCNO>
Chiral Compactifications of 6D Conformal Theories


  We construct chiral N=1 gauge theories in 4D by compactifying the 6D
Blum-Intriligator (1,0) theories of 5-branes at $A_k$ singularities on $T^2$
with a nontrivial bundle of the global U(1) symmetry of these theories.

</DOC>
<DOC>
<DOCNO> 100032 </DOCNO>
On zeros of polynomials orthogonal over a convex domain


  We establish a discrepancy theorem for signed measures, with a given positive
part, which are supported on an arbitrary convex curve. As a main application,
we obtain a result concerning the distribution of zeros of polynomials
orthogonal on a convex domain.

</DOC>
<DOC>
<DOCNO> 178896 </DOCNO>
Short-range correlations in low-lying nuclear excited states


  The electromagnetic transitions to various low-lying excited states of 16O,
48Ca and 208Pb are calculated within a model which considers the short-range
correlations. In general the effects of the correlations are small and do not
explain the required quenching to describe the data.

</DOC>
<DOC>
<DOCNO> 68866 </DOCNO>
QCD analysis of near-to-planar 3-jet events


  Perturbative QCD analysis is presented of the cumulative out-of-plane
momentum distribution in the near-to-planar e+e- annihilation events, K_out <<
Q. In this kinematical region multiple gluon radiation effects become
essential. They are resummed with the single-logarithmic accuracy, which
programme includes the 2-loop treatment of the basic radiation and matching
with the exact O(alpha_s^2) result.
  Dedicated experimental analyses of 3-jet event characteristics are of special
interest for the study of the non-perturbative confinement effects.

</DOC>
<DOC>
<DOCNO> 12499 </DOCNO>
Ab Initio studies of the atomic structure and electronic density of


  We propose a method to simulate a-Si and a-Si:H using an ab initio approach
based on the Harris functional and thermally amorphisized periodically
continued cells with at least 64 atoms, and calculate their radial distribution
functions. Hydrogen incorporation was achieved via diffusive random addition.
The electronic density of states (DOS) is obtained using density functional
theory with the aid of both the Harris-functional and Kohn-Sham-LDA approaches.
Two time steps are used, 2.44 and 10 fs for the pure, and 0.46 and 2 fs for the
hydrogenated, to see their effect on the topological and DOS structure of the
samples. The calculated long time-step radial features of a-Si are in very good
agreement with experiment whereas for a-Si:H the short time-step partial and
total radial features agree well; for the long time-step simulation molecular
hydrogen appears during annealing.The long time-step a-Si has a well defined
gap with two dangling bonds, that clears and increases upon hydrogen addition
and relaxation, as expected. The short time-step structures have more defects,
both dangling and floating bonds, that are less characteristic of a good
sample; however the radial structures of a-Si:H are in better agreement with
experiment indicating that the experimental work was done on defective samples.

</DOC>
<DOC>
<DOCNO> 116947 </DOCNO>
Testing and Implementation Progress on the Advanced Photon Source (APS)


  An S-band linear accelerator is the source of particles and the front end of
the Advanced Photon Source injector. In addition, it supports a low-energy
undulator test line (LEUTL) and drives a free-electron laser (FEL). A
waveguide-switching and distribution system is now under construction. The
system configuration was revised to be consistent with the recent change to
electron-only operation. There are now six modulator-klystron subsystems, two
of which are being configured to act as hot spares for two S-band transmitters
each, so that no single failure will prevent injector operation. The two
subsystems are also used to support additional LEUTL capabilities and off-line
testing. Design considerations for the waveguide-switching subsystem, topology
selection, control and protection provisions, high-power test results, and
current status are described

</DOC>
<DOC>
<DOCNO> 151212 </DOCNO>
An Extended Abelian Chern-Simons Model and the Symplectic Projector


  The Symplectic Projector Method is applied to discuss quantisation aspects of
an extended Abelian model with a pair of gauge potentials coupled by means of a
mixed Chern-Simons term. We focuss on a field content that spans an N=2-D=3
supersymmetric theory whenever scalar and fermionic matter is suitably coupled
to the family of gauge potentials.

</DOC>
<DOC>
<DOCNO> 68175 </DOCNO>
Boltzmann equations for neutrinos with flavor mixings


  With a view of applications to the simulations of supernova explosion and
proto neutron star cooling, we derive the Boltzmann equations for the neutrino
transport with the flavor mixing based on the real time formalism of the
nonequilibrium field theory and the gradient expansion of the Green function.
The relativistic kinematics is properly taken into account. The advection terms
are derived in the mean field approximation for the neutrino self-energy whiles
the collision terms are obtained in the Born approximation. The resulting
equations take the familiar form of the Boltzmann equation with corrections due
to the mixing both in the advection part and in the collision part. These
corrections are essentially the same as those derived by Sirera et al. for the
advection terms and those by Raffelt et al. for the collision terms,
respectively, though the formalism employed here is different from theirs. The
derived equations will be easily implemented in numerical codes employed in the
simulations of supernova explosions and proto neutron star cooling.

</DOC>
<DOC>
<DOCNO> 120853 </DOCNO>
The Giant Radio Galaxy MRC B0319-454: Circumnuclear Structure of the


  We present optical and near-infrared images and spectra of ESO248-G10, the
host of giant radio galaxy MRC B0319-454. From near-infrared colours, the
active nucleus is shown to be reddened by hot dust emission or dust extinction.
Star forming regions are identified beyond a radius of 5" (8.1 kpc) where hot
gas is prevalent. The optical spectrum shows gas rotation at speeds of up to
350km/s out to >=32kpc along the radio axis. A model is proposed in which the
giant elliptical is triaxial with the radio axis along the short axis, and the
figure rotation is around the long axis. From the model, the angles of the
principal axes are psi=34 degrees, theta=65 degrees, and phi=19 degrees with
axis ratios of B/A=0.75 and C/A=0.69. A second velocity feature from 5" to 15"
to the north-east of the nucleus is proposed to be a merging gas-rich galaxy
inducing star formation while settling into an orbit about the figure rotation
axis.

</DOC>
<DOC>
<DOCNO> 72331 </DOCNO>
Resonance enhancement of particle production during reheating


  We found a consistent equation of reheating after inflation, which shows that
for small quantum fluctuations the frequencies of resonance are slighted
different from the standard ones. Quantum interference is taken into account
and we found that at large fluctuations the process mimics very well the usual
parametric resonance but proceed in a different dynamical way. The analysis is
made in a toy quantum mechanical model and we discuss further its extension to
quantum field theory.

</DOC>
<DOC>
<DOCNO> 70088 </DOCNO>
Screened Perturbation Theory to Three Loops


  The thermal physics of a massless scalar field with a phi^4 interaction is
studied within screened perturbation theory (SPT). In this method the
perturbative expansion is reorganized by adding and subtracting a mass term in
the lagrangian. We consider several different mass prescriptions that
generalize the one-loop gap equation to two-loop order. We calculate the
pressure and entropy to three-loop order and the screening mass to two-loop
order. In contrast to the weak-coupling expansion, the SPT-improved
approximations appear to converge even for rather large values of the coupling
constant.

</DOC>
<DOC>
<DOCNO> 13447 </DOCNO>
New Physics of the $30^\circ$ Partial Dislocation in Silicon Revealed


  Based on {\em ab initio} calculation, we propose a new structure for the
fundamental excitation of the reconstructed 30$^\circ$ partial dislocation in
silicon. This soliton has a rare structure involving a five-fold coordinated
atom near the dislocation core. The unique electronic structure of this defect
is consistent with the electron spin resonance signature of the hitherto
enigmatic thermally stable R center of plastically deformed silicon. We present
the first {\em ab initio} determination of the free energy of the soliton,
which is also in agreement with the experimental observation. This
identification suggests the possibility of an experimental determination of the
density of solitons, a key defect in understanding the plastic flow of the
material.

</DOC>
<DOC>
<DOCNO> 11532 </DOCNO>
Discrete Financial Means: When exception rules, mean means nothing;


  The origin of macroscopic complexity is traced in a wide range of systems
(imunology, ecology, finance, marketing, etc) to the discrete and
auto-catalytic (i.e. multiplicative) character of their elementary components.
Even in the simplest conditions which naively would lead to the complete
"death" of any dynamics, these 2 properties lead to the emergence of
self-organized adaptive collective objects. In turn, these objects insure the
survival of a very rich and unexpectedly resilient macroscopic "life".

</DOC>
<DOC>
<DOCNO> 102280 </DOCNO>
Trilinear relations between the tetrahedron volumes in a cluster


  We prove elegant trilinear formulas connecting products of volumes of
Euclidean tetrahedra with vertices taken from a given set of 6 points. We
propose a way for generalizing those formulas.

</DOC>
<DOC>
<DOCNO> 120092 </DOCNO>
Free-fall accretion and emitting caustics in wind-fed X-ray sources


  In wind-fed X-ray binaries the accreting matter is Compton cooled and falls
freely onto the compact object. The matter has a modest angular momentum $l$
and accretion is quasi-spherical at large distances from the compact object.
Initially small non-radial velocities grow in the converging supersonic flow
and become substantial in the vicinity of the accretor. The streamlines with
$l>(GMR_*)^{1/2}$ (where $M$ and $R_*$ are the mass and radius of the compact
object) intersect outside $R_*$ and form a two-dimensional caustic which emits
X-rays. The streamlines with low angular momentum, $l<(GMR_*)^{1/2}$, run into
the accretor. If the accretor is a neutron star, a large X-ray luminosity
results. We show that the distribution of accretion rate/luminosity over the
star surface is sensitive to the angular momentum distribution of the accreting
matter. The apparent luminosity depends on the side from which the star is
observed and can change periodically with the orbital phase of the binary. The
accretor then appears as a `Moon-like' X-ray source.

</DOC>
<DOC>
<DOCNO> 122618 </DOCNO>
Dynamics of low-energy nuclear forces and Solar Neutrino Problems in the


  The Solar Neutrino Problems (SNP's) are analysed in the Nambu-Jona-Lasinio
model of light nuclei. In this model a possible clue to the solution of the
SNP's is in the reduction of the solar neutrino fluxes relative to the
predicted by the Standard Solar Model through the decrease of the solar core
temperature. The former can be realized through the enhancement of the
astrophysical factor for the solar proton burning. The enhancement the upper
bound of which is restricted by the helioseismological data goes dynamically
via the contribution of the nucleon tensor current coupled to the deuteron. The
agreement of the reduced solar neutrino fluxes with the experimental data can
be reached within a scenario of vacuum two-flavour neutrino oscillations
without a fine tuning of the neutrino-flavour oscillation parameters. In the
Nambu-Jona-Lasinio model of light nuclei an enhancement of the astrophysical
factor for the solar proton burning entails a change of the cross sections for
neutrino and anti-neutrino disintegration of the deuteron at low energies. This
provides a theoretical foundation for a new check of a value of the
astrophysical factor in terrestrial laboratories.

</DOC>
<DOC>
<DOCNO> 120624 </DOCNO>
Delayed X-Ray Afterglows from Obscured Gamma-Ray Bursts in Star-Forming


  For Gamma-Ray Bursts occurring in dense star-forming regions, the X-ray
afterglow behavior minutes to days after the trigger may be dominated by the
small-angle scattering of the prompt X-ray emission off dust grains. We give a
simple illustrative model for the X-ray light curves at different X-ray
energies, and discuss possible implications. A bump followed by a steeper decay
in soft X-rays is predicted for bursts which are heavily obscured in the
optical.

</DOC>
<DOC>
<DOCNO> 12866 </DOCNO>
Friction Laws for Elastic Nano-Scale Contacts


  The effect of surface curvature on the law relating frictional forces F with
normal load L is investigated by molecular dynamics simulations as a function
of surface symmetry, adhesion, and contamination. Curved, non-adhering, dry,
commensurate surfaces show a linear dependency, F proportional to L, similar to
dry flat commensurate or amorphous surfaces and macroscopic surfaces. In
contrast, curved, non-adhering, dry, amorphous surfaces show F proportional to
L^(2/3) similar to friction force microscopes. In our model, adhesive effects
are most adequately described by the Hertz plus offset model, as the
simulations are confined to small contact radii. Curved lubricated or
contaminated surfaces show again different behavior; details depend on how much
of the contaminant gets squeezed out of the contact. Also, it is seen that the
friction force in the lubricated case is mainly due to atoms at the entrance of
the tip.

</DOC>
<DOC>
<DOCNO> 150575 </DOCNO>
Boundary states and non-abelian orbifolds


  In this note the open string partition function is analyzed carefully in a
way to reveal the group-theoretical aspects. For the simple cases of ADE
orbifolds with regular Chan-Paton action a prescription for consistent boundary
states is given. In the process of outlining how they encode McKay
correspondence, we argue that this results from a non-trivial conspiracy of
numerical factors in the string amplitudes.

</DOC>
<DOC>
<DOCNO> 102667 </DOCNO>
Weak singularity dynamics in a nonlinear viscous medium


  We consider a system of nonlinear equations which can be reduced to a
degenerate parabolic equation. In the case $x\in\bR^2$ we obtained necessary
conditions for the existence of a weakly singular solution of heat wave type
($\codim\sing\supp=1$) and of vortex type ($\codim\sing\supp=2$). These
conditions have the form of a sequence of differential equations and allow one
to calculate the dynamics of the singularity support. In contrast to the
methods used traditionally for degenerate parabolic equations, our approach is
not based on comparison theorems.

</DOC>
<DOC>
<DOCNO> 9736 </DOCNO>
Untwisting of a cholesteric elastomer by a mechanical field


  A mechanical strain field applied to a monodomain cholesteric elastomer will
unwind the helical director distribution. There is an analogy with the
classical problem of an electric field applied to a cholesteric liquid crystal,
but with important differences. Frank elasticity is of minor importance unless
the gel is very weak. The interplay is between director anchoring to the rubber
elastic matrix and the external mechanical field. Stretching perpendicular to
the helix axis induces the uniform unwound state via the elimination of sharp,
pinned twist walls above a critical strain. Unwinding through conical director
states occurs when the elastomer is stretched along the helical axis.

</DOC>
<DOC>
<DOCNO> 99340 </DOCNO>
Quadratic minima and modular forms II


  We give upper bounds on the size of the gap between a non-zero constant term
and the next non-zero Fourier coefficient of an entire level two modular form.
We give upper bounds for the minimum positive integer represented by a level
two even positive-definite quadratic form. These bounds extend partial results
in part I.

</DOC>
<DOC>
<DOCNO> 9348 </DOCNO>
Static and dynamic image potential for tunneling into a Luttinger liquid


  We study electron tunneling from a tip or a lead into an interacting quantum
wire described by Luttinger liquid theory. Within a WKB-type approach, the
Coulomb interaction between the wire and the tunneling electrons, as well as
the finite traversal time are taken into account. Although the static image
potential is only logarithmically suppressed against the bare Coulomb
interaction, the dynamic image potential is not strong enough to alter
power-law exponents entering the tunneling density of states.

</DOC>
<DOC>
<DOCNO> 121347 </DOCNO>
Polarization Limits in Compact Symmetric Objects


  We present results of multifrequency polarimetric VLBA observations of 34
compact radio sources. The observations are part of a large survey undertaken
to identify CSOs Observed in the Northern Sky (COINS). Based on VLBI continuum
surveys of ~2000 compact radio sources, we have defined a sample of 52 CSOs and
CSO candidates. Positive identification of CSOs is contingent upon acquiring
multi-frequency observations in order to correctly identify the core of the
source, which is expected to have a strongly inverted spectrum. We also expect
CSOs to exhibit very little polarized flux. Despite the fact that synchrotron
emission is intrinsically highly polarized, less than 0.5% fractional
polarization is seen in low resolution studies of CSOs at frequencies up to 5
GHz. One possible explanation for the low observed linear polarization from
CSOs is that their radiation is depolarized as it passes through a magnetized
plasma associated with a circumnuclear torus. This interpretation is consistent
with the unified scheme of AGN, and also with the recent detections of
free-free and HI absorption in CSOs.
  Here we present limits on the polarized flux density at 8.4 GHz and ~1 mas
resolution for 21 CSOs and candidates in the COINS sample.

</DOC>
<DOC>
<DOCNO> 8005 </DOCNO>
Exact solution of site and bond percolation on small-world networks


  We study percolation on small-world networks, which has been proposed as a
simple model of the propagation of disease. The occupation probabilities of
sites and bonds correspond to the susceptibility of individuals to the disease
and the transmissibility of the disease respectively. We give an exact solution
of the model for both site and bond percolation, including the position of the
percolation transition at which epidemic behavior sets in, the values of the
two critical exponents governing this transition, and the mean and variance of
the distribution of cluster sizes (disease outbreaks) below the transition.

</DOC>
<DOC>
<DOCNO> 118359 </DOCNO>
Secondary caustics in close multiple lenses


  We investigate the caustic structure of a lens composed by a discrete number
of point-masses, having mutual distances smaller than the Einstein radius of
the total mass of the system. Along with the main critical curve, it is known
that the lens map is characterized by secondary critical curves producing small
caustics far from the lens system. By exploiting perturbative methods, we
derive the number, the position, the shape, the cusps and the area of these
caustics for an arbitrary number of close multiple lenses. Very interesting
geometries are created in some particular cases. Finally we review the binary
lens case where our formulae assume a simple form.

</DOC>
<DOC>
<DOCNO> 119872 </DOCNO>
An Overview of Optical Galaxy Searches and their Completeness


  Dust and stars in the Milky Way create a ``Zone of Avoidance'' (ZOA) in the
distribution of optically visible galaxies of about 25% of the sky. To reduce
this gap, optical searches for partially obscured galaxies have been performed.
The status of these deep searches, in particular their completeness as a
function of foreground extinction are discussed. Using existing sky surveys,
over 50000 previously unknown galaxies have been identified. The surveys cover
practically the whole ZOA. It is shown that these surveys are complete for
galaxies with extinction-corrected diameters D^o ge 1.3 arcmin to extinction
levels of A_B le 3.0 mag. Incorporating these new data in a whole-sky map of
galaxies complete to D^o ge 1.3 arcmin finds the ZOA reduced by a factor of
about 2 to 2.5, respectively from extinction levels of A_B = 1.0 mag to A_B =
3.0 mag (see Fig.~4).

</DOC>
<DOC>
<DOCNO> 169568 </DOCNO>
New nonlinear coherent states and some of their nonclassical properties


  We construct a displacement operator type nonlinear coherent state and
examine some of its properties. In particular it is shown that this nonlinear
coherent state exhibits nonclassical properties like squeezing and
sub-Poissonian behaviour.

</DOC>
<DOC>
<DOCNO> 174553 </DOCNO>
The reaction dynamics of the 16O(e,e'p) cross section at high missing


  We measured the cross section and response functions (R_L, R_T, and R_LT) for
the 16O(e,e'p) reaction in quasielastic kinematics for missing energies 25 <=
E_miss <= 120 MeV at various missing momenta P_miss <= 340 MeV/c. For 25 <
E_miss < 50 MeV and P_miss \approx 60 MeV/c, the reaction is dominated by
single-nucleon knockout from the 1s1/2-state. At larger P_miss, the
single-particle aspects are increasingly masked by more complicated processes.
For E_miss > 60 MeV and P_miss > 200 MeV/c, the cross section is relatively
constant. Calculations which include contributions from pion exchange currents,
isobar currents and short-range correlations account for the shape and the
transversity but only for half of the magnitude of the measured cross section.

</DOC>
<DOC>
<DOCNO> 68467 </DOCNO>
Running of the heavy quark production current and 1/k potential in QCD


  The 1/k contribution to the heavy quark potential is first generated at one
loop order in QCD. We compute the two loop anomalous dimension for this
potential, and find that the renormalization group running is significant. The
next-to-leading-log coefficient for the heavy quark production current near
threshold is determined. The velocity renormalization group result includes the
alpha_s^3 ln^2(alpha_s) ``non-renormalization group logarithms'' of Kniehl and
Penin.

</DOC>
<DOC>
<DOCNO> 170601 </DOCNO>
Quantum Multi-object Search Algorithm with the Availability of Partial


  Consider the unstructured search of an unknown number l of items in a large
unsorted database of size N. The multi-object quantum search algorithm consists
of two parts. The first part of the algorithm is to generalize Grover's
single-object search algorithm to the multi-object case and the second part is
to solve a counting problem to determine l.
 In this paper, we study the multi-object quantum search algorithm (in
continuous time), but in a more structured way by taking into account the
availability of partial information. The modeling of available partial
information is done simply by the combination of several prescribed, possibly
overlapping, information sets with varying weights to signify the reliability
of each set. The associated statistics is estimated and the algorithm
efficiency and complexity are analyzed.
  Our analysis shows that the search algorithm described here may not be more
efficient than the unstructured (generalized) multi-object Grover search if
there is ``misplaced confidence''. However, if the information sets have a
``basic confidence'' property in the sense that each information set contains
at least one search item, then a quadratic speedup holds on a much smaller data
space, which further expedite the quantum search for the first item.

</DOC>
<DOC>
<DOCNO> 170668 </DOCNO>
Selecting molecules in the vibrational and rotational ground state by


  A beam of diatomic molecules scattered off a standing wave laser mode splits
according to the rovibrational quantum state of the molecules. Our numerical
calculation shows that single state resolution can be achieved by properly
tuned, monochromatic light. The proposed scheme allows for selecting
non-vibrating and non-rotating molecules from a thermal beam, implementing a
laser Maxwell's demon to prepare a rovibrationally cold molecular ensemble.

</DOC>
<DOC>
<DOCNO> 8004 </DOCNO>
Orientational pinning and transverse voltage: Simulations and


  We study the dependence of the transport properties of square Josephson
Junctions arrays with the direction of the applied dc current, both
experimentally and numerically. We present computational simulations of
current-voltage curves at finite temperatures for a single vortex in the array
($Ha^2/\Phi_0=f=1/L^2$), and experimental measurements in $100\times1000$
arrays under a low magnetic field corresponding to $f\approx0.02$. We find that
the transverse voltage vanishes only in the directions of maximum symmetry of
the square lattice: the [10] and [01] direction (parallel bias) and the [11]
direction (diagonal bias). For orientations different than the symmetry
directions, we find a finite transverse voltage which depends strongly on the
angle $\phi$ of the current. We find that vortex motion is pinned in the [10]
direction ($\phi=0$), meaning that the voltage response is insensitive to small
changes in the orientation of the current near $\phi=0$. We call this
phenomenon orientational pinning. This leads to a finite transverse critical
current for a bias at $\phi=0$ and to a transverse voltage for a bias at
$\phi\not=0$. On the other hand, for diagonal bias in the [11] direction the
behavior is highly unstable against small variations of $\phi$, leading to a
rapid change from zero transverse voltage to a large transverse voltage within
a few degrees. This last behavior is in good agreement with our measurements in
arrays with a quasi-diagonal current drive.

</DOC>
<DOC>
<DOCNO> 40150 </DOCNO>
Search for gamma gamma decays of a Higgs boson produced in association


  A serach for gamma gamma decays of Higgs boson is performed in the data
sample collected at LEP with the ALEPH detector between 1991 and 1999. This
corresponds to an integrated luminosity of 672 pb-1 centre-of-mass energies
ranging from 88 to 202 GeV. The search is based on topologies arising from a
Higgs boson produced in association with a fermion pair via the Higgs-strahlung
process e+e- -> Hffbar, with ffbar = nunubar, e+e-, mu+mu-, tau+tau- or
qqbar... (CERN)

</DOC>
<DOC>
<DOCNO> 101277 </DOCNO>
Integral mappings and the principle of local reflexivity for


  The operator space analogue of the {\em strong form} of the principle of
local reflexivity is shown to hold for any von Neumann algebra predual, and
thus for any $C^{*}$-algebraic dual. This is in striking contrast to the
situation for $C^{*}$-algebras, since, for example, $K(H)$ does not have that
property. The proof uses the Kaplansky density theorem together with a careful
analysis of two notions of integrality for mappings of operator spaces.

</DOC>
<DOC>
<DOCNO> 85305 </DOCNO>
Multi-Black Hole Sectors of AdS_3 Gravity


  We construct and discuss solutions of SO(1,2) x SO(1,2) Chern-Simons theory
which correspond to multiple BTZ black holes. These solutions typically have
additional singularities, the simplest cases being special conical
singularities with a 2 pi surplus angle. There are solutions with singularities
inside a common outer horizon, and other solutions with naked conical
singularities. Previously such singularities have been ruled out on physical
grounds, because they do not obey the geodesic equation. We find however that
the Chern-Simons gauge symmetry may be used to locate all such singularities to
the horizons, where they necessarily follow geodesics. We are therefore led to
conclude that these singular solutions correspond to physically sensible
geometries.
  Boundary charges at infinity are only sensitive to the total mass and spin of
the black holes, and not to the distribution among the black holes. We
therefore argue that a holographic description in terms of a boundary conformal
field theory should represent both single and multiple BTZ solutions with the
same asymptotic charges. Then sectors with multiple black holes would
contribute to the black hole entropy calculated from a boundary CFT.

</DOC>
<DOC>
<DOCNO> 102628 </DOCNO>
On the frequency of vanishing of quadratic twists of modular L-functions


  We present theoretical and numerical evidence for a random matrix theoretic
approach to a conjecture about vanishings of quadratic twists of certain
L-functions

</DOC>
<DOC>
<DOCNO> 12798 </DOCNO>
Low-temperature heat transfer in nanowires


  The new regime of low-temperature heat transfer in suspended nanowires is
predicted. It takes place when (i) only ``acoustic'' phonon modes of the wire
are thermally populated and (ii) phonons are multiply scattered by the point
defects during the transfer through the wire. Qualitatively, the main
peculiarities of the heat transfer originate due to appearance of the flexural
modes with high density of states in the wire phonon spectrum. They give rise
to the T^{1/2} temperature dependence of the wire thermal conductance. The
experimental situations where the new regime is likely to be detected are
discussed.

</DOC>
<DOC>
<DOCNO> 68698 </DOCNO>
Symplectic Symmetry of the Neutrino Mass and the See-Saw Mechanism


  We investigate the algebraic structure of the most general neutrino mass
Hamiltonian and place the see-saw mechanism in an algebraic framework. We show
that this Hamiltonian can be written in terms of the generators of an Sp(4)
algebra. The Pauli-Gursey transformation is an SU(2) rotation which is embedded
in this Sp(4) group. This SU(2) also generates the see-saw mechanism.

</DOC>
<DOC>
<DOCNO> 80808 </DOCNO>
Quantum gravity as a theory of quantized area bits fitting together


  Non-Abelian Gauss law is interpreted in terms of area bits described in a
local frame which fit together into closed surfaces and the Non-Abelian Stokes
law in terms of length bits described in a local frame which fit together into
closed loops. A new equation relating the area variables and the phase space
variables (or equivalently, angular momentum variables of the lattice
Yang-Mills theory and phase space variables of the continuum theory) is
obtained. Canonical quantization applied to these variables implies area
quantization. A complete orthonormal basis of states satisfying the Gauss
constraint is obtained.It has the interpretation of quantized area bits with
undefined orientations and edges but fitting together into closed surfaces.

</DOC>
<DOC>
<DOCNO> 9474 </DOCNO>
Acoustoelectric effect in a finite-length ballistic quantum channel


  The dc current induced by a coherent surface acoustic wave (SAW) of wave
vector q in a ballistic channel of length L is calculated. The current contains
two contributions, even and odd in q. The even current exists only in a
asymmetric channel, when the electron reflection coefficients r_1 and r_2 at
both channel ends are different. The direction of the even current does not
depend on the direction of the SAW propagation, but is reversed upon
interchanging r_1 and r_2. The direction of the odd current is correlated with
the direction of the SAW propagation, but is insensitive to the interchange of
r_1 and r_2. It is shown that both contributions to the current are non zero
only when the electron reflection coefficients at the channel ends are energy
dependent. The current exhibits geometric oscillations as function of qL. These
oscillations are the hallmark of the coherence of the SAW and are completely
washed out when the current is induced by a flux of non-coherent phonons. The
results are compared with those obtained previously by different methods and
under different assumptions.

</DOC>
<DOC>
<DOCNO> 85312 </DOCNO>
Does the radioactive decay obey the Poisson statistics?


  It is shown that a nontrivial quantum structure of our space at macroscopic
scales, which may exist as a relic of quantum gravity processes in the early
universe, gives rise to a new phenomenon: spontaneous origin of an interference
picture in every physical process. This explains why statistical distributions
in radioactivity measurements may be different from the Poisson distribution.

</DOC>
<DOC>
<DOCNO> 151907 </DOCNO>
Open group transformations


  Recent results on finite open group transformations are reviewed.

</DOC>
<DOC>
<DOCNO> 71824 </DOCNO>
Optimizing T-violating Effects for Neutrino Oscillations in Matter


  Matter effects may strongly enhance the Jarlskog factor J in T and
CP-violating three-neutrino oscillation probabilities. However, we show that
when J is enhanced, the same matter effects suppress the oscillating factors
and increase the oscillation length. The net result is that there is no large
enhancement in measurable probabilities for earth-bound experiments using
neutrino parameters suggested by current experiments. We show that by an
appropriate choice of the experimental parameters, neutrino energy and travel
length, the T-violating probability can be enhanced by matter effects over
their vacuum values by 50%. Our approach is analytical, allowing considerable
insight into the underlying physics.

</DOC>
<DOC>
<DOCNO> 101522 </DOCNO>
Proof of the Boltzmann-Sinai Ergodic Hypothesis for Typical Hard Disk


  We consider the system of $N$ ($\ge2$) hard disks of masses $m_1,...,m_N$ and
radius $r$ in the flat unit torus $\Bbb T^2$. We prove the ergodicity
(actually, the B-mixing property) of such systems for almost every selection
$(m_1,...,m_N;r)$ of the outer geometric parameters.

</DOC>
<DOC>
<DOCNO> 122337 </DOCNO>
A Large Eddy Simulation of Turbulent Compressible Convection:


  We present results of two simulations of the convection zone, obtained by
solving the full hydrodynamic equations in a section of a spherical shell. The
first simulation has cylindrical rotation contours (parallel to the rotation
axis) and a strong meridional circulation, which traverses the entire depth.
The second simulation has isorotation contours about mid-way between cylinders
and cones, and a weak meridional circulation, concentrated in the uppermost
part of the shell.
  We show that the solar differential rotation is directly related to a
latitudinal entropy gradient, which pervades into the deep layers of the
convection zone. We also offer an explanation of the angular velocity shear
found at low latitudes near the top. A non-zero correlation between radial and
zonal velocity fluctuations produces a significant Reynolds stress in that
region. This constitutes a net transport of angular momentum inwards, which
causes a slight modification of the overall structure of the differential
rotation near the top. In essence, the {\it thermodynamics controls the
dynamics through the Taylor-Proudman momentum balance}. The Reynolds stresses
only become significant in the surface layers, where they generate a weak
meridional circulation and an angular velocity `bump'.

</DOC>
<DOC>
<DOCNO> 116248 </DOCNO>
Localized Superluminal solutions to Maxwell equations propagating along


  We show that localized (non-evanescent) solutions to Maxwell equations exist,
which propagate without distortion along normal waveguides with Superluminal
speed.

</DOC>
<DOC>
<DOCNO> 101523 </DOCNO>
Maximal Thurston-Bennequin Number of Two-Bridge Links


  We compute the maximal Thurston-Bennequin number for a Legendrian two-bridge
knot or oriented two-bridge link in standard contact R^3, by showing that the
upper bound given by the Kauffman polynomial is sharp. As an application, we
present a table of maximal Thurston-Bennequin numbers for prime knots with nine
or fewer crossings.

</DOC>
<DOC>
<DOCNO> 70773 </DOCNO>
Multiplicities in Parton and Dipole QCD Cascades


  Evolution equations for multiplicities in QCD cascades can, both in the
parton and dipole picture, be used to estimate corrections beyond the formal
accuracy of the modified leading log approximation (MLLA). The differences
between the two pictures, and other uncertainties beyond first order MLLA
corrections, are here investigated in some detail. For example, I discuss how
some colour suppressed corrections, which cannot be determined without better
knowledge of non-perturbative QCD, are related to the question of colour
reconnection. A generalized evolution equation for the dipole cascade is also
presented.

</DOC>
<DOC>
<DOCNO> 9354 </DOCNO>
Monte Carlo Study of the S=1/2 and S=1 Heisenberg Antiferromagnet on a


  We present a quantum Monte Carlo study of a Heisenberg antiferromagnet on a
spatially anisotropic square lattice, where the coupling strength in the
x-direction ($J_x$) is different from that in the y-direction ($J_y$). By
varying the anisotropy $\alpha$ from 0 to 1, we interpolate between the
one-dimensional chain and the two-dimensional isotropic square lattice. Both
$S=1/2$ and S=1 systems are considered separately in order to facilitate
comparison. The temperature dependence of the uniform susceptibility and the
spin-spin correlation length are computed down to very low temperatures for
various values of $\alpha$. For S=1, the existence of a quantum critical point
at $\alpha^{S=1}_c=0.040(5)$ as well as the scaling of the spin gap is
confirmed. Universal quantities predicted from the ${\cal O}(3)$ nonlinear
$\sigma$ model agree with our results at $\alpha=0.04$ without any adjustable
parameters. On the other hand, the $S=1/2$ results are consistent with
$\alpha^{S=1/2}_c=0$, as discussed by a number of previous theoretical studies.
Experimental implications for $S=1/2$ compounds such as Sr$_2$CuO$_3$ are also
discussed.

</DOC>
<DOC>
<DOCNO> 10373 </DOCNO>
On the origin of biquadratic exchange in spin 1 chains


  One dimensional spin 1 systems may have a rich phase diagram including
Haldane gap and dimerized phases if the usually very small biquadratic exchange
becomes significant. We show that this unlikely condition may be fulfilled in
electron systems with quasi-degenerate orbitals. This mechanism may have been
experimentally realized in the spin 1 chain LiVGe$_2$O$_6$. The implications
for the exploration of the physics and quantum chemistry of spin 1 chains are
discussed.

</DOC>
<DOC>
<DOCNO> 12367 </DOCNO>
On Eigenvalues and Eigenfunctions Absent in the Actual Solid State


  In this letter new, closed and compact analytic expressions for the
evaluation of resonant energies, resonant bound-states, eigenvalues and
eigenfunctions for both scattering and bounded $n$-cell systems are reported.
It is shown that for (scattering and bounded) 1-D systems the eigenfunctions
$\Psi_{\mu ,\nu}(z)$ are simple and well defined functions of the Chebyshev
polynomials of the second kind $U_{n}$, and the energy eigenvalues $E_{\mu ,\nu
}$ (in the $\mu $-th band) are determined by the zeros of these polynomials.
New insights on the energy gap and the localization effect induced by phase
coherence are shown.

</DOC>
<DOC>
<DOCNO> 80761 </DOCNO>
Hadron Structure in Lattice QCD: Exploring the Gluon Wave Functional


  The use of lattice QCD to understand hadron structure is described, with
particular emphasis on exploring the role of glue.

</DOC>
<DOC>
<DOCNO> 9153 </DOCNO>
Upper critical fields of quasi-low-dimensional superconductors with


  Quasi-low-dimensional type II superconductors in parallel magnetic fields are
studied when singlet pairing interactions and relatively weak triplet pairing
interactions coexist. Singlet and triplet components of order parameter are
mixed at high fields, and at the same time an inhomogeneous superconducting
state called a Fulde-Ferrell-Larkin-Ovchinnikov state occurs. As a result, the
triplet pairing interactions enhance the upper critical field of
superconductivity remarkably even at temperatures far above the transition
temperature of parallel spin pairing. It is found that the enhancement is very
large even when the triplet pairing interactions are so weak that a high field
phase of parallel spin pairing may not be observed in practice. A possible
relvance of the result in organic superconductors and a
hybrid-ruthenate-cuprate superconductor is discussed.

</DOC>
<DOC>
<DOCNO> 120212 </DOCNO>
HIIphot: Automated Photometry of HII Regions Applied to M51


  We have developed a robust, automated method, hereafter designated HIIphot,
which enables accurate photometric characterization of HII regions while
permitting genuine adaptivity to irregular source morphology. HIIphot utilizes
object-recognition techniques to make a first guess at the shapes of all
sources then allows for departure from such idealized ``seeds'' through an
iterative growing procedure. Photometric corrections for spatially coincident
diffuse emission are derived from a low-order surface fit to the background
after exclusion of all detected sources. We present results for the
well-studied, nearby spiral M51 in which 1229 HII regions are detected above
the 5-sigma level. A simple, weighted power-law fit to the measured H-alpha
luminosity function (HII LF) above log L_H-alpha = 37.6 gives alpha =
-1.75+/-0.06, despite a conspicuous break in the HII LF observed near L_H-alpha
= 10^38.9. Our best- fit slope is marginally steeper than measured by Rand
(1992), perhaps reflecting our increased sensitivity at low luminosities and to
notably diffuse objects. HII regions located in interarm gaps are
preferentially less luminous than counterparts which constitute M51's
grand-design spiral arms and are best fit with a power-law slope of alpha =
-1.96+/-0.15. We assign arm/interarm status for HII regions based upon the
varying surface brightness of diffuse emission as a function of position
throughout the image. Using our measurement of the integrated flux contributed
by resolved HII regions in M51, we estimate the diffuse fraction to be
approximately 0.45 -- in agreement with the determination of Greenawalt et al.
(1998). Automated processing of degraded datasets is undertaken to gauge
systematic effects associated with limiting spatial resolution and sensitivity.

</DOC>
<DOC>
<DOCNO> 117330 </DOCNO>
Anomalous scaling in homogeneous isotropic turbulence


  The anomalous scaling exponents $\zeta_{n}$ of the longitudinal structure
functions $S_{n}$ for homogeneous isotropic turbulence are derived from the
Navier-Stokes equations by using field theoretic methods to develop a low
energy approximation in which the Kolmogorov theory is shown to act effectively
as a mean field theory. The corrections to the Kolmogorov exponents are
expressed in terms of the anomalous dimensions of the composite operators which
occur in the definition of $S_{n}$. These are calculated from the anomalous
scaling of the appropriate class of nonlinear Green's function, using an $uv$
fixed point of the renormalisation group, which thereby establishes the
connection with the dynamics of the turbulence. The main result is an algebraic
expression for $\zeta_{n}$, which contains no adjustable constants.
  It is valid at orders $n$ below $% g_{\ast}^{-1}$, where $g_{\ast}$ is the
fixed point coupling constant. This expression is used to calculate $\zeta
_{n}$ for orders in the range $% n=2$ to 10, and the results are shown to be in
good agreement with experimental data, key examples being $\zeta_{2}=0.7$,
$\zeta_{3}=1$ and $% \zeta_{6}=1.8$.

</DOC>
<DOC>
<DOCNO> 71062 </DOCNO>
Hadronic Equipartition of Quark and Glue Momenta


  If the ``glue'' which binds quarks within hadrons takes the form of strings,
then a virial theorem may be derived which shows how the total hadron four
momentum splits up into a quark contribution plus a glue contribution. The
hadrons made up of light quarks exhibit an equipartion of four momentum into
equal parts quarks and glue. The agreement with the experimental ``parton''
distribution four momentum sum rule is quite satisfactory as is the string
fragmentation model.

</DOC>
<DOC>
<DOCNO> 68513 </DOCNO>
New Physics Search in B Meson Decays


  We discuss new physics search within the minimal supergravity model by using
a possible large direct CP asymmetry in $B^{\pm} \to K^{\pm}\phi,
K^{0}\pi^{\pm}$ decays and B meson rare decays.

</DOC>
<DOC>
<DOCNO> 72172 </DOCNO>
Electroweak Interactions: Summary


  The session on precision studies of electroweak interactions is summarized.
The contributions address the bilinear, trilinear, quartic as well as
heavy-quark interactions of the electroweak gauge bosons. This makes up a
picture of the physics of electroweak symmetry and symmetry breaking which can
be investigated with the proposed design of e+e- Linear Colliders and
detectors.

</DOC>
<DOC>
<DOCNO> 13088 </DOCNO>
Spin and Orbital Order in Itinerant Ferromagnets


  The long-standing problem of the effect of correlations on the ferromagnetism
of is apparently nearing solution. The ferromagnetism of transition metals
compounds, for instance doped manganites, poses a new question: is there some
kind of orbital order coexisting with itinerant ferromagnetism? The ideas and
techniques introduced by Gutzwiller should be of use again.

</DOC>
<DOC>
<DOCNO> 10338 </DOCNO>
Frustration in d-wave Superconducting Circuits: $\pi$-Ring Behaviour


  A closed superconducting circuit containing an odd number of $\pi$-junctions,
a $\pi$-ring, has a finite current in the ground state. We explicitly construct
such rings for d-wave superconductors and demonstrate the existence of
spontaneous currents by direct self-consistent solutions to the Bogoliubov de
Gennes equations. We show that the current has a topological origin due to the
frustration of the d-wave order parameter, which is only partially explained by
the Sigrist-Rice tunneling formula.

</DOC>
<DOC>
<DOCNO> 11710 </DOCNO>
Theory of Ferromagnetic Superconductivity


  It is argued that the pairing symmetry realized in a ferromagnetic
superconductor UGe$_2$ must be a non-unitary triplet pairing. This particular
state is free from the Pauli limitation and can survive under a huge internal
molecular filed. To check our identification we examine its basic properties
and several experiments are proposed. In particular, the external field is used
to raise $T_c$ by controlling the internal spontaneous dipole field.

</DOC>
<DOC>
<DOCNO> 120386 </DOCNO>
Magnetic propeller in symbiotic stars


  Rapidly spinning magnetic white dwarfs in symbiotic stars may pass through
the propeller stage. It is believed that a magnetic propeller acts in two such
stars CH Cyg and
 MWC 560. We review a diversity of manifestations of the propeller there. In
these systems in a quiescent state the accretion onto a white dwarf from the
strong enough wind of a companion star is suppressed by the magnetic field, and
the hot component luminosity is low. Since the gas stored in the envelope
eventually settles to the corotation radius the star-propeller reveals itself
by long-time outbursts, short-time brightness dips, strong amplitude
flickering, ejection of a powerful wind and jets. The envelope appears to be
stratified and inhomogeneous because of the shock pumping of the propeller. At
this stage, at which catastrophic transitions to the accretion stage and back
are possible, the release of energy and angular momentum of the white dwarf is
maximum. Using this property, we estimate the magnetic field strength of the
white dwarfs in CH Cyg and MWC 560 to be of order $10^8$ G.
   The most spectacular property of these stars - jets - is inherently
connected with the propeller. This suggests hydromagnetic models of jet
acceleration.

</DOC>
<DOC>
<DOCNO> 121678 </DOCNO>
The outer-halo globular cluster NGC 6229. IV. Variable stars


  We present time-series B, V photometry of NGC 6229, obtained with the purpose
of providing the first extensive CCD variability study of this cluster. As a
result, we were able to obtain periods for all NGC 6229 variables, with the
exception of five stars from the Borissova et al. (1997) candidate list located
very close to the cluster center. Two variable stars suspected by Carney,
Fullton, & Trammell (1991) are first-overtone RR Lyrae (RRc) stars, whereas
seven of the 12 candidates from Borissova et al. (1997) are confirmed variables
-- three of them being fundamental RR Lyrae (RRab) pulsators, two
first-overtone pulsators, one eclipsing binary (most likely an Algol system)
and one bright star whose variability status could not be satisfactorily
determined. A new image subtraction method (ISM) suggested by Alard (1999) has
been employed which, together with the Welch & Stetson (1993) technique, has
allowed us to discover twelve new RR Lyrae variables in the cluster, for which
ephemerides are provided. Ten of these are RRab's, whereas the other two are
RRc's. As originally suggested by Mayer (1961), NGC 6229 is clearly an
Oosterhoff type I globular cluster. We also confirm that V8 is a Population II
Cepheid of the W Virginis type, and suspect that this is the case for V22 as
well.
  The physical properties of the NGC 6229 RR Lyrae population are compared
against those of M3 (NGC 5272) using several different methods, including a
standard period-shift analysis. Possible differences between these two clusters
are discussed.

</DOC>
<DOC>
<DOCNO> 70817 </DOCNO>
A New Connection between Central Engine Weak Physics and the Dynamics of


  We demonstrate a qualitatively new aspect of the dynamics of Gamma-Ray Burst
(GRB) fireballs: the development of a substantial dispersion in the proton
component in fireballs in which neutron decoupling occurs and is sufficiently
pronounced. This effect depends sensitively on the neutron to proton ratio in
the fireball, becoming more dramatic with increasing neutron excess. Simple
physical arguments and transport calculations indicate that the dispersion in
Lorentz factor of the protons can be of order the final mean Lorentz factor of
the fireball. We show how plasma instabilities could play an important role in
the evolution of the fireball and how they might ultimately govern the
development of such a velocity dispersion in the proton component. The role of
these instabilities in setting/diminishing a proton Lorentz factor dispersion
represents a new and potentially important venue for the study of plasma
instabilities. Significant dispersion in the proton velocities translates into
fewer protons attaining the highest Lorentz factors. This is tantamount to a
reduction in the total energy required to attain a given Lorentz factor for the
highest energy protons. As well, a proton component dispersion can have
consequences for the electromagnetic and neutrino signature of GRBs.

</DOC>
<DOC>
<DOCNO> 151721 </DOCNO>
On the q-deformed differential operators and induced su(n)-Toda field


  We build in this paper the algebra of q-deformed pseudo-differential
operators shown to be an essential step towards setting a q-deformed
integrability program. In fact, using the results of this q-deformed algebra,
we derive the q-analogues of the generalised KdV hierarchy. We focus in
particular the first leading orders of this q-deformed hierarchy namely the
q-KdV and q- Boussinesq integrable systems. We present also the
q-generalisation of the conformal transformations of the currents and discuss
the primarity condition of the fields by using the Volterra gauge group
transformations for the q-covariant Lax operators. An induced
su(n)-Toda(su(2)-Liouville) field theory construction is discussed and other
important features are presented.

</DOC>
<DOC>
<DOCNO> 121333 </DOCNO>
STIS Echelle Observations of NGC 4151: Variable Ionization of the


  We present echelle observations of the intrinsic UV absorption lines in the
Seyfert galaxy NGC 4151, which were obtained with the Space Telescope Imaging
Spectrograph (STIS) on the Hubble Space Telescope on 1999 July 19. The UV
continuum flux at 1450 Angstroms decreased by factor of about four over the
previous two years and there was a corresponding dramatic increase in the
column densities of the low-ionization absorption lines (e.g., Si II, Fe II,
and Al II), presumably as a result of a decrease in the ionizing continuum. In
addition to the absorption lines seen in previous low states, we identify a
large number of Fe II absorption lines that arise from metastable levels as
high as 4.1 eV above the ground state, indicating high densities (> 10^6
cm^-3). We find that the transient absorption feature in the blue wing of the
broad C IV emission, seen in a Goddard High Resolution Spectrograph spectrum
and thought to be a high-velocity C~IV component, is actually a Si II
fine-structure absorption line at a radial velocity of -560 km/s (relative to
systemic). We also demonstrate that the ``satellite'' emission lines of C~IV
found in International Ultraviolet Explorer spectra are actually regions of
unabsorbed continuum plus broad emission that become prominent when the UV
continuum of NGC 4151 is in a low state.

</DOC>
<DOC>
<DOCNO> 118510 </DOCNO>
Metal Abundances in the Hot Interstellar Medium in Early-Type Galaxies


  We have analyzed ASCA data of 27 early-type galaxies, and studied the
properties of their X-ray emitting ISM (Inter Stellar
  Medium) in detail. We found that overlapping lines and free-bound continuum
cause strong coupling in the derived abundances of various elements. The
abundance determination is also difficult due to the uncertainties in the Fe-L
atomic physics, because Fe-L lines couple with O and Ne K-lines. However, when
abundances of $\alpha$-elements are fixed, all the plasma codes give similar Fe
abundances with a scattering of only 20-30%. To relax the strong coupling among
the elements, we included 20% systematic errors in the Fe-L region of the
spectra. Then, in X-ray luminous galaxies, the derived abundance of Fe and
$\alpha$-elements both became $\sim 1$ solar within a factor of 2. This result
relaxes the previous severe discrepancy between the ISM and stellar
metallicities. The ISM metallicity in X-ray fainter galaxies is still
uncertain, but we can at least constrain that contribution from type-Ia SN to
the ISM abundance is lower than in X-ray luminous systems. These results
strongly suggest that a large fraction of SN Ia products have escaped into
intergalactic space.

</DOC>
<DOC>
<DOCNO> 70092 </DOCNO>
Form factors for $B-->\pi l\nu$ decay in a model constrained by chiral


  The form factors for the $B-->\pi$ transition are evaluated in the entire
momentum transfer range by using the constraints obtained in the framework
combining the heavy quark expansion and chiral symmetry for light quarks and
the quark model. In particular, we calculate the valence quark contributions
and show that it together with the equal time commutator contribution simulate
a B-meson pole q^2-dependence of form factors in addition to the usual vector
meson B^{*}-pole diagram for $B --> \pi l\nu$ in the above framework. We
discuss the predictions in our model, which provide an estimate of |V_{ub}|^2.

</DOC>
<DOC>
<DOCNO> 9967 </DOCNO>
Two-dimensional Granular Gas of Inelastic Spheres with Multiplicative


  We study a two-dimensional granular gas of inelastic spheres subject to
multiplicative driving proportional to a power $|v(\vec{x})|^{\delta}$ of the
local particle velocity $v(\vec{x})$. The steady state properties of the model
are examined for different values of $\delta$, and compared with the
homogeneous case $\delta=0$. A driving linearly proportional to $v(\vec{x})$
seems to reproduce some experimental observations which could not be reproduced
by a homogeneous driving. Furthermore, we obtain that the system can be
homogenized even for strong dissipation, if a driving inversely proportional to

</DOC>
<DOC>
<DOCNO> 151464 </DOCNO>
Remarks on the existence of Spinning Membrane Actions


  It has been recently argued by some authors that is impossible to construct a
Weyl invariant spinning membrane action, where the $S$-supersymmetry associated
with the 3D superconformal algebra, is relinquished without gauge fixing.
Contrary to those assertions, we show why it is possible to construct a
Weyl-invariant spinning polynomial membrane action, without curvature
terms,where $both$ the conformal boost symmetry and $S$-supersymmetry are
explicitly broken by the action. It is shown that the gauge algebra $closes$
despite that the two latter symmetries are broken . For this to happen, a
modifed $Q$-supersymmetry transformation, a sort of new $Q+K+S$ ``sum `` rule,
is required that generates the compensating terms to cancel the spurious
contributions fromthe $S$ and conformal boost anomalous transformations. A
substantial discussion of the quantization of the spinning membrane and
anomalies is given. We review briefly the role that this spinning membrane
action may have in the theory of $D$-branes, Skyrmions and BPS monopoles in the
large $N$-limit of SU(N) Yang-Mills .

</DOC>
<DOC>
<DOCNO> 13928 </DOCNO>
Thermodynamic Limit for Polydisperse Fluids


  We examine the thermodynamic limit of fluids of hard core particles that are
polydisperse in size and shape. In addition, particles may interact
magnetically. Free energy of such systems is a random variable because it
depends on the choice of particles. We prove that the thermodynamic limit
exists with probability 1, and is independent of the choice of particles. Our
proof applies to polydisperse hard-sphere fluids, colloids and ferrofluids. The
existence of a thermodynamic limit implies system shape and size independence
of thermodynamic properties of a system.

</DOC>
<DOC>
<DOCNO> 119285 </DOCNO>
Meteor Stream Membership Criteria


  Criteria for the membership of individual meteors in meteor streams are
discussed from the point of view of their mathematical and also physical
properties. Discussion is also devoted to the motivation. It is shown that
standardly used criteria (mainly D-criterion of Southworth and Hawkins, 1963)
have unusual mathematical properties in the sense of a term ``distance'',
between points in a phase space, and, physical motivation and realization for
the purpose of obtaining their final form is not natural and correct, and,
moreover, they lead also to at least surprising astrophysical results. General
properties of possible criteria are discussed. A new criterion for the
membership in meteor streams is suggested. It is based on probability theory.
Finally, a problem of meteor orbit determination for known parent body is
discussed.

</DOC>
<DOC>
<DOCNO> 7972 </DOCNO>
Motion of dark solitons in trapped Bose-Einstein condensates


  We use a multiple time scale boundary layer theory to derive the equation of
motion for a dark (or `grey') soliton propagating through an effectively
one-dimensional cloud of Bose-Einstein condensate, assuming only that the
background density and velocity vary slowly on the soliton scale. We show that
solitons can exhibit viscous or radiative acceleration (anti-damping), which we
estimate as slow but observable on experimental time scales.

</DOC>
<DOC>
<DOCNO> 152220 </DOCNO>
Gauge Symmetry Breaking and Generalized Monopole in Non-BPS D-Brane


  Based on the DBI action for the four coincident non-BPS D9-branes in the type
IIA string theory we demonstrate that the gauge symmetry breaking through the
tachyon condensation into the generalized monopole of codimension five produces
a pair of two coincident BPS D4-branes. The nontrivial gauge field
configuration is studied and shown to yield the non-zero generalized magnetic
charge. We discuss how this explicit demonstration is related with the higher
K-theory group.

</DOC>
<DOC>
<DOCNO> 120437 </DOCNO>
HST Observations of Vibrationally-Excited Molecular Hydrogen in Cluster


  We report new HST NICMOS and WFPC2 imaging of emission-line nebulae in the
central galaxies of 3 clusters of galaxies purported to host massive cooling
flows, NGC1275, A2597, and PKS0745. The spectral signature of vibrationally-
excited molecular hydrogen (VEMH) has been seen in every galaxy searched so far
in a cluster cooling flow with an optical emission line nebula. We have
discovered that the VEMH gas extends several kpc from the centers of A2597 and
PKS0745, while the vibrationally-excited molecular hydrogen in NGC1275 appears
to be mostly confined to its nucleus, with some extended emission <1 kpc from
the center. The VEMH in A2597 and PKS0745-191 seems to be nearly co-spatial
with the optical emission-line filaments in those systems. Candidates for
heating the nebulae are X-ray irradiation by the ICM, UV fluorescence by young
stars, and shocks. UV heating by young stars provides the most satisfactory
explanation for the H2 emission in A2597 and PKS0745; X-ray irradiation is
energetically unlikely and strong shocks (v>40 km/s) are ruled out by the high
H2/H-alpha ratios. If UV heating is the main energy input, a few billion solar
masses of molecular gas is present in A2597 and PKS0745. UV irradiation models
predict a significant amount of 1-2 micron emission from higher excitation H2
transitions and moderate far infrared luminosities (~1e44/h^2 erg/s) for A2597
and PKS0745. Even in the context of UV fluorescence models, the total amount of
H2 gas and star formation inferred from these observations is too small to
account for the cooling flow rates and longevities inferred from the X-rays. We
note an interesting new constraint on cooling flow models: the radio sources do
not provide a significant amount of shock heating, and therefore cannot
counterbalance the cooling of the X-ray gas in the cluster cores.

</DOC>
<DOC>
<DOCNO> 12353 </DOCNO>
d=3 random field behavior near percolation


  The highly diluted antiferromagnet Mn(0.35)Zn(0.65)F2 has been investigated
by neutron scattering for H>0. A low-temperature (T<11K), low-field (H<1T)
pseudophase transition boundary separates a partially antiferromagnetically
ordered phase from the paramagnetic one. For 1<H<7T at low temperatures, a
region of antiferromagnetic order is field induced but is not enclosed within a
transition boundary.

</DOC>
<DOC>
<DOCNO> 9251 </DOCNO>
Effect of Substitutional Impurities on the Electronic States and


  Low temperature quantum corrections to the density of states (DOS) and the
conductivity are examined for a two-dimensional(2D) square crystal with
substitutional impurities. By summing the leading logarithmic corrections to
the DOS its energy dependence near half-filling is obtained. It is shown that
substitutional impurities do not suppress the van Hove singularity at the
middle of the band, however they change its energy dependence strongly. Weak
disorder due to substitutional impurities in the three-dimensional simple cubic
lattice results in a shallow dip in the center of the band. The calculation of
quantum corrections to the conductivity of a 2D lattice shows that the
well-known logarithmic localization correction exists for all band fillings.
Furthermore the magnitude of the correction increases as half-filling is
approached. The evaluation of the obtained analytical results shows evidence
for delocalized states in the center of the band of a 2D lattice with
substitutional impurities.

</DOC>
<DOC>
<DOCNO> 102019 </DOCNO>
Line-closed matroids, quadratic algebras, and formal arrangements


  Let $G$ be a matroid on ground set \A. The Orlik-Solomon algebra $A(G)$ is
the quotient of the exterior algebra \E on \A by the ideal \I generated by
circuit boundaries. The quadratic closure $\bar{A}(G)$ of $A(G)$ is the
quotient of \E by the ideal generated by the degree-two component of \I. We
introduce the notion of \nbb set in $G$, determined by a linear order on \A,
and show that the corresponding monomials are linearly independent in the
quadratic closure $\bar{A}(G)$. As a consequence, $A(G)$ is a quadratic algebra
only if $G$ is line-closed. An example of S.~Yuzvinsky proves the converse
false. These results generalize to the degree $r$ closure of $\A(G)$.
  The motivation for studying line-closed matroids grew out of the study of
formal arrangements. This is a geometric condition necessary for \A to be free
and for the complement $M$ of \A to be a $K(\pi,1)$ space. Formality of \A is
also necessary for $A(G)$ to be a quadratic algebra. We clarify the
relationship between formality, line-closure, and other matroidal conditions
related to formality. We give examples to show that line-closure of $G$ is not
necessary or sufficient for $M$ to be a $K(\pi,1)$, or for \A to be free.

</DOC>
<DOC>
<DOCNO> 117825 </DOCNO>
Evolution of the Blue Luminosity-to-Baryon Mass Ratio of Clusters of


  We derive the ratio of total blue luminosity to total baryon mass, LB/Mb, for
massive (Mgas at the Abell radius is \ge 1 \times 10^{13} h^{-2.5} \Msolar)
clusters of galaxies up to z \simeq 1 from the literature. Twenty-two clusters
in our sample are at z > 0.1. Assuming that the relative mix of hot gas and
galaxies in clusters does not change during cluster evolution, we use LB/Mb to
probe the star formation history of the galaxy population as a whole in
clusters. We find that LB/Mb of clusters increases with redshift from
LB/Mb=0.024 (solar units) at z = 0 to \simeq 0.06 at z=1, indicating a factor
of 2-3 brightening (we assume H0=70 km/s/Mpc). This amount of brightening is
almost identical to the brightening of the M/LB ratio of early-type galaxies in
clusters at 0.02 \le z \le 0.83 reported by van Dokkum et al. (1998). We
compare the observed brightening of LB/Mb with luminosity evolution models for
the galaxy population as a whole, changing the e-folding time of star formation
\tau by 0.1 \le \tau \le 5 Gyr and the formation redshift \zF by 2 \le \zF <
\infty. We find that \tau=0.1 Gyr 'single burst' models with \zF \ge 3 and
\tau=5 Gyr 'disk' models with arbitrary \zF are consistent with the observed
brightening, while models with \tau=1-2 Gyr tend to predict too steep
brightening. We also derive the ratio of blue luminosity density to baryon
density for field galaxies, adopting \Omega_b h^2 = 0.02, and find that blue
luminosity per unit baryon is similar in clusters and in fields up to z \simeq
1 within the observational uncertainties.

</DOC>
<DOC>
<DOCNO> 102571 </DOCNO>
Nongraded Infinite-Dimensional Simple Lie Algebras


  Nongraded infinite-dimensional Lie algebras appeared naturally in the theory
of Hamiltonian operators, the theory of vertex algebras and their
multi-variable analogues. They play important roles in mathematical physics.
This survey article is written based on the author's seminar talks on nongraded
infinite-dimensional simple Lie algebras. The key constructional ingredients of
our Lie algebras are locally-finite derivations. The structure spaces of some
families of these simple Lie algebras can be viewed as analogues of vector
bundles with Lie algebras as fibers. We also believe that some of our simple
Lie algebras could be related to noncommutative geometry.

</DOC>
<DOC>
<DOCNO> 72009 </DOCNO>
Supersymmetric origin of a low $a_{J/psi}$ CP asymmetry


  We show that general Minimal Supersymmetric extensions of the Standard Model
(MSSM) allow for a CP asymmetry in B --> J/psi K(S) well bellow the SM
expectations with dominant Supersymmetric contributions to epsilon_K and
epsilon'/epsilon. Indeed, we provide an explicit example of an MSSM with
non-universal soft breaking terms fully consistent with the low results of this
asymmetry recently announced by Babar and Belle collaborations.

</DOC>
<DOC>
<DOCNO> 9033 </DOCNO>
Output from Bose condensates in tunnel arrays: the role of mean-field


  We present numerical studies of atomic transport in 3D and 1D models for a
mode-locked, pulsed atom laser as realized by Anderson and Kasevich [Science
281 (1998) 1686] using an elongated Bose condensate of ${}^{87}$Rb atoms poured
into a vertical optical lattice. From our 3D results we ascertain in a
quantitative manner the role of mean-field interactions in determining the
shape and the size of the pulses in the case of Gaussian transverse
confinement. By comparison with 1D simulations we single out a best-performing
1D reduction of the mean-field interactions, which yields quantitatively useful
predictions for all main features of the matter output.

</DOC>
<DOC>
<DOCNO> 102743 </DOCNO>
Linearization of Poisson actions and singular values of matrix products


  We prove that the linearization functor from the category of Hamiltonian
K-actions with group-valued moment maps in the sense of Lu, to the category of
ordinary Hamiltonian K-actions, preserves products up to symplectic
isomorphism. As an application, we give a new proof of the Thompson conjecture
on singular values of matrix products and extend this result to the case of
real matrices. We give a formula for the Liouville volume of these spaces and
obtain from it a hyperbolic version of the Duflo isomorphism.

</DOC>
<DOC>
<DOCNO> 121878 </DOCNO>
On the Nonspherical Nature of Halo Formation


  We present a new collapse condition to describe the formation of dark halos
via nonspherical gravitational clustering. This new nonspherical collapse
condition is obtained by the logical generalization of the spherical model to
the nonspherical one. By solving a diffusion-like random matrix equation with
the help of the Monte Carlo method, we show that this nonspherical collapse
condition yields the mass function derived by Sheth & Tormen (1999) which has
been shown to be in excellent agreement with the recent N-body results of high
resolution. We expect that this nonspherical collapse condition might provide
us a deeper insight into the structure formation, and suggest that it should be
widely applied to various cosmological issues such as the galaxy merging
history, the galaxy bias, and so forth.

</DOC>
<DOC>
<DOCNO> 12913 </DOCNO>
Fractionally charged magneto-excitons


  The photoluminescence (PL) spectrum of a two-dimensional electron gas (2DEG)
in the fractional quantum Hall regime is studied. The response of the 2DEG to
an optically injected valence hole depends on the separation d between the
electron and hole layers. At d smaller than the magnetic length lambda, the PL
spectrum shows recombination of neutral (X) and charged (X-) excitons. At
d>lambda, the hole binds one or two Laughlin quasielectrons (QE) of the 2DEG to
form fractionally charged excitons (FCX), hQE or hQE2. Different FCX states
have different optical properties, and their stability depends critically on
the presence of QE's in the 2DEG. This explains discontinuities observed in the
PL spectrum at such (Laughlin) filling factors as nu=1/3 or 2/3.

</DOC>
<DOC>
<DOCNO> 72141 </DOCNO>
Cosmology and particle physics


  The state of our understanding of cosmology is reviewed from an astrophysical
cosmologist point of view with a particular emphasis given to recent
observations and their impact. Discussion is then presented on the implications
for particle physics.

</DOC>
<DOC>
<DOCNO> 69185 </DOCNO>
The three loop on-shell renormalization of QCD and QED


  We describe a calculation of the on-shell renormalization factors in QCD and
QED at the three loop level. Explicit results for the fermion mass
renormalization factor Zm and the on-shell fermion wave function
renormalization constant Z2 are given. We find that at O(alpha_s^3) the wave
function renormalization constant Z2 in QCD becomes gauge dependent also in the
on-shell scheme, thereby disproving the ``gauge-independence'' conjecture based
on an earlier two-loop result. As a byproduct, we derive an O(alpha_s^3)
contribution to the anomalous dimension of the heavy quark field in HQET.

</DOC>
<DOC>
<DOCNO> 10852 </DOCNO>
Elasticity of Gaussian and nearly-Gaussian phantom networks


  We study the elastic properties of phantom networks of Gaussian and
nearly-Gaussian springs. We show that the stress tensor of a Gaussian network
coincides with the conductivity tensor of an equivalent resistor network, while
its elastic constants vanish. We use a perturbation theory to analyze the
elastic behavior of networks of slightly non-Gaussian springs. We show that the
elastic constants of phantom percolation networks of nearly-Gaussian springs
have a power low dependence on the distance of the system from the percolation
threshold, and derive bounds on the exponents.

</DOC>
<DOC>
<DOCNO> 118441 </DOCNO>
A New Strategy for the Routine Detection & Imaging of Faint Radio


  In this paper I outline a new strategy for the routine detection and imaging
of faint (sub-mJy and microJy) radio sources with VLBI and SVLBI. The strategy
relies on a combination of in-beam phase-referencing, wide-field VLBI imaging
and simultaneous correlation of multiple field centres. A combination of these
techniques, together with the steeply rising radio source counts observed at cm
wavelengths, permit routine high resolution observations of radio sources
previously considered too faint for conventional VLBI.

</DOC>
<DOC>
<DOCNO> 8236 </DOCNO>
The monoclinic phase in PZT: new light on morphotropic phase boundaries


  A summary of the work recently carried out on the morphotropic phase boundary
(MPB) of PZT is presented. By means of x-ray powder diffraction on ceramic
samples of excellent quality, the MPB has been successfully characterized by
changing temperature in a series of closely spaced compositions. As a result,
an unexpected monoclinic phase has been found to exist in between the
well-known tetragonal and rhombohedral PZT phases. A detailed structural
analysis, together with the investigation of the field effect in this region of
compositions, have led to an important advance in understanding the mechanisms
responsible for the physical properties of PZT as well as other piezoelectric
materials with similar morphotropic phase boundaries.

</DOC>
<DOC>
<DOCNO> 170238 </DOCNO>
Quantum mechanics without interpretation


  It is shown that the independence of the continuum hypothesis points to the
unique definite status of the set of intermediate cardinality: the intermediate
set exists only as a subset of continuum. This latent status is a consequence
of duality of the members of the set. Due to the structural inhomogeneity of
the intermediate set, its complete description falls into several "sections"
(theories) with their special main laws, dimensions, and directions, i.e., the
complete description of the one-dimensional intermediate set is
multidimensional. Quantum mechanics is one of these theories.

</DOC>
<DOC>
<DOCNO> 116408 </DOCNO>
Symmetry breaking of vibrating interfaces: a mechanism for morphogenesis


  We show that very small-amplitude oscillations of a highly symmetric, spheric
or cylindrical, interface (thin membrane) between two fluids can result in
inhomogeneous instability and breaking of the interface symmetry: the frequency
of the breathing vibration selects the spatial symmetry. This mechanism may
govern morphogenesis.

</DOC>
<DOC>
<DOCNO> 68839 </DOCNO>
Magnetic Screening in Hot Non-Abelian Gauge Theory


  We analyze the large distance and low-momentum behavior of the magnetic gluon
propagator of the SU(2) gauge theory at finite temperature. Lattice
calculations within the 4-dimensional as well as the effective, dimensionally
reduced 3-dimensional gauge theories in generalized Landau gauges and MAG show
that the magnetic propagator is strongly infrared suppressed in Landau gauges
but stays large and finite in MAG. Despite these differences in the
low-momentum behavior of the propagator calculated in different gauges the
magnetic fields are exponentially screened in all gauges considered. From the
propagator calculated in maximally Abelian gauge we find for the screening
mass, m_M = (1.48 +/- 0.17) T at T=2 T_c.

</DOC>
<DOC>
<DOCNO> 11241 </DOCNO>
Superconductivity from Undressing


  Photoemission experiments in high $T_c$ cuprates indicate that quasiparticles
are heavily 'dressed' in the normal state, particularly in the low doping
regime. Furthermore these experiments show that a gradual undressing occurs
both in the normal state as the system is doped and the carrier concentration
increases, as well as at fixed carrier concentration as the temperature is
lowered and the system becomes superconducting. A similar picture can be
inferred from optical experiments. It is argued that these experiments can be
simply understood with the single assumption that the quasiparticle dressing is
a function of the local carrier concentration. Microscopic Hamiltonians
describing this physics are discussed. The undressing process manifests itself
in both the one-particle and two-particle Green's functions, hence leads to
observable consequences in photoemission and optical experiments respectively.
An essential consequence of this phenomenology is that the microscopic
Hamiltonians describing it break electron-hole symmetry: these Hamiltonians
predict that superconductivity will only occur for carriers with hole-like
character, as proposed in the theory of hole superconductivity.

</DOC>
<DOC>
<DOCNO> 9886 </DOCNO>
A Rigorous Derivation of the Gross-Pitaevskii Energy Functional for a


  We consider the ground state properties of an inhomogeneous two-dimensional
Bose gas with a repulsive, short range pair interaction and an external
confining potential. In the limit when the particle number $N$ is large but
$\bar\rho a^2$ is small, where $\bar\rho$ is the average particle density and
$a$ the scattering length, the ground state energy and density are rigorously
shown to be given to leading order by a Gross-Pitaevskii (GP) energy functional
with a coupling constant $g\sim 1/|\ln(\bar\rho a^2)|$. In contrast to the 3D
case the coupling constant depends on $N$ through the mean density. The GP
energy per particle depends only on $Ng$. In 2D this parameter is typically so
large that the gradient term in the GP energy functional is negligible and the
simpler description by a Thomas-Fermi type functional is adequate.

</DOC>
<DOC>
<DOCNO> 117184 </DOCNO>
The Effect of an Under-Dense Plasma Density Gradient on the


  The space charge limited emission of ions from a target in the focus of an
intense relativistic electron beam is studied analytically for the case of a
spatially varying target density profile. In particular, the emission in the
presence of an under-dense plasma shelf in contact with the solid density
target dramatically differs from the case of an abrupt solid-vacuum boundary.
It is found that an under-dense gradient scale length several times that of the
beam radius at the focus reduces the emission by at least an order of magnitude
over that to be expected from a solid-vacuum boundary.

</DOC>
<DOC>
<DOCNO> 170332 </DOCNO>
Tuning the scattering length on the ground triplet state of Cs_2


  We develop two schemes for tuning the scattering length on the ground triplet
state of Cs_2. First, an absolute value of the triplet scattering length of
^{133}Cs_2 is determined using the experimental data (Fioretti et al,
Eur.Phys.J. 5, 389 (1999)). We demonstrate that the large scattering length can
be made small and positive by coupling of the ^3\Sigma_u^+ (6S + 6S) potential
to the ^3\Pi_g state by strong off-resonant radiation. A weaker laser field
coupling the ^3\Sigma_u^+ (6S + 6S) continuum to the lowest bound level of the
excited ^3\Sigma_g^+ (6S + 6P) also leads to a small positive scattering
length. In addition, the scattering length of the ^{135}Cs isotope is found to
be positive. The method used solves the Schroedinger equation for two
electronic states coupled by an electromagnetic field with approximations
employed. The scattering length is determined from calculated continuum
wavefunctions of low energy.

</DOC>
<DOC>
<DOCNO> 170775 </DOCNO>
Induced measures in the space of mixed quantum states


  We analyze several product measures in the space of mixed quantum states. In
particular we study measures induced by the operation of partial tracing. The
natural, rotationally invariant measure on the set of all pure states of a N x
K composite system, induces a unique measure in the space of N x N mixed states
(or in the space of K x K mixed states, if the reduction takes place with
respect to the first subsystem). For K=N the induced measure is equal to the
Hilbert-Schmidt measure, which is shown to coincide with the measure induced by
singular values of non-Hermitian random Gaussian matrices pertaining to the
Ginibre ensemble. We compute several averages with respect to this measure and
show that the mean entanglement of $N \times N$ pure states behaves as lnN-1/2.

</DOC>
<DOC>
<DOCNO> 68462 </DOCNO>
Remarks on anomalous U(1) symmetries in string theory


  Anomalous U(1) gauge symmetries appear frequently both in heterotic and type
I/type II string theory. In the heterotic case we find at most a single
anomalous U(1), while in open string theories several such symmetries can
appear. We review the properties of the anomalous gauge bosons, the appearance
of Fayet-Iliopoulos terms and the concept of heterotic-type I duality.
Phenomenological applications of these symmetries might be different in the
type I/type II case compared to the heterotic one.

</DOC>
<DOC>
<DOCNO> 68474 </DOCNO>
Gluelump spectrum in the QCD string model


  Spectrum of gluons in the adjoint source field is computed analytically using
the QCD string Hamiltonian, containing only one parameter - string tension,
fixed by meson and glueball spectrum. Spin splitting is shown to be small. A
good agreement is observed with spatially generated gluelump states measured on
the lattice. Important role of gluelumps defining the behaviour of
field-strength correlators is stressed and correspondence with earlier
computations of the latter is established.

</DOC>
<DOC>
<DOCNO> 85007 </DOCNO>
Continuous-time histories: observables, probabilities, phase space


  In this paper we elaborate on the structure of the continuous-time histories
description of quantum theory, which stems from the consistent histories
scheme. In particular, we examine the construction of history Hilbert space,
the identification of history observables and the form of the decoherence
functional (the object that contains the probability information). It is shown
how the latter is equivalent to the closed-time-path (CTP) generating
functional. We also study the phase space structure of the theory first through
the construction of general representations of the history group (the analogue
of the Weyl group) and the implementation of a histories Wigner-Weyl transform.
The latter enables us to write quantum theory solely in terms of phase space
quantities. These results enable the implementation of an algorithm for
identifying the classical (stochastic) limit of a general quantum system.

</DOC>
<DOC>
<DOCNO> 10249 </DOCNO>
Spin Tunneling in Mn-12 Cannot be Assisted by Phonons at Millikelvin


  Recently, Bellessa et al in a Physical Review Letter entitled
"Phonon-Assisted Tunneling in High-Spin Molecules: Experimental Evidence",
reported observation of a peak in the imaginary part of the ac-susceptibility
of Mn-12 molecular nanomagnet, that decreases strongly below 0.1 K down to 0.02
K. They explained this effect by a "phonon-induced tunneling process". The
purpose of this Comment is to show that the explanation of Bellessa et al is
logically inconsistent and physically impossible. All formulas in the Letter
supporting that explanation are incorrect.

</DOC>
<DOC>
<DOCNO> 13262 </DOCNO>
Phase Diagram of Bilayer Composite Fermion States


  We construct a class of composite fermion states for bilayer electron systems
in a strong transverse magnetic field, and determine quantitatively the phase
diagram as a function of the layer separation, layer thickness, and electron
density. We find, in general, that there are several transitions, and that the
incompressible phases are separated by compressible ones. The paired states of
composite fermions, described by Pfaffian wave functions, are also considered.

</DOC>
<DOC>
<DOCNO> 10817 </DOCNO>
Continuously varying exponents in a sandpile model with dissipation near


  We consider the directed Abelian sandpile model in the presence of sink sites
whose density f_t at depth t below the top surface varies as c~1/t^chi. For
chi>1 the disorder is irrelevant. For chi<1, it is relevant and the model is no
longer critical for any nonzero c. For chi=1 the exponents of the avalanche
distributions depend continuously on the amplitude c of the disorder. We
calculate this dependence exactly, and verify the results with simulations.

</DOC>
<DOC>
<DOCNO> 12219 </DOCNO>
Projected SO(5) Hamiltonian for Cuprates and Its Applications


  The projected SO(5) (pSO(5)) Hamiltonian incorporates the quantum spin and
superconducting fluctuations of underdoped cuprates in terms of four bosons
moving on a coarse grained lattice. A simple mean field approximation can
explain some key feautures of the experimental phase diagram: (i) The Mott
transition between antiferromagnet and superconductor, (ii) The increase of T_c
and superfluid stiffness with hole concentration x and (iii) The increase of
antiferromagnetic resonance energy as sqrt{x-x_c} in the superconducting phase.
We apply this theory to explain the ``two gaps'' problem found in underdoped
cuprate Superconductor-Normal- Superconductor junctions. In particular we
explain the sharp subgap Andreev peaks of the differential resistance, as
signatures of the antiferromagnetic resonance (the magnon mass gap). A critical
test of this theory is proposed. The tunneling charge, as measured by shot
noise, should change by increments of Delta Q= 2e at the Andreev peaks, rather
than by Delta Q=e as in conventional superconductors.

</DOC>
<DOC>
<DOCNO> 169935 </DOCNO>
Estimation of Buttiker-Landauer traversal time based on the visibility


  We present a proposal for the estimation of B\"uttiker-Landauer traversal
time based on the visibility of transmission current. We analyze the tunneling
phenomena with a time-dependent potential and obtain the time-dependent
transmission current. We found that the visibility is directly connected to the
traversal time. Furthermore, this result is valid not only for rectangular
potential barrier but also for general form of potential to which the WKB
approximation is applicable . We compared these results with the numerical
values obtained from the simulation of Nelson's quantum mechanics. Both of them
fit together and it shows our method is very effective to measure
experimentally the traversal time.

</DOC>
<DOC>
<DOCNO> 83112 </DOCNO>
Description of GADEL


  This article describes the first implementation of the GADEL system : a
Genetic Algorithm for Default Logic. The goal of GADEL is to compute extensions
in Reiter's default logic. It accepts every kind of finite propositional
default theories and is based on evolutionary principles of Genetic Algorithms.
Its first experimental results on certain instances of the problem show that
this new approach of the problem can be successful.

</DOC>
<DOC>
<DOCNO> 85509 </DOCNO>
Brane Inflation from Mirage Cosmology


  We study the cosmological evolution of a D3-brane universe in a type 0 string
background. We follow the brane-universe along the radial coordinate of the
background and we calculate the energy density which is induced on the brane
because of its motion in the bulk. We find that for some typical values of the
parameters the brane-universe has an inflationary phase.

</DOC>
<DOC>
<DOCNO> 13824 </DOCNO>
Molecular dynamics simulations of spin and pure liquids with preserving


  A new methodology is developed to integrate numerically the equations of
motion for classical many-body systems in molecular dynamics simulations. Its
distinguishable feature is the possibility to preserve, independently on the
size of the time step, all the conservation laws inherent in the description
without breaking the time reversibility. As a result, an implicit second-order
algorithm is derived and applied to pure as well as spin liquids for which the
dynamics is characterized by the conservation of total energy, linear and
angular momenta as well as magnetization and individual spin lengths. It is
demonstrated on the basis of Lennard-Jones and Heisenberg fluid models that
when such quantities as energy and magnetization must be conserved perfectly,
the new algorithm turns out to be more efficient than popular decomposition
integrators and standard predictor-corrector schemes.

</DOC>
<DOC>
<DOCNO> 123086 </DOCNO>
AMiBA: Array for Microwave Background Anisotropy


  As part of a 4-year Cosmology and Particle Astrophysics (CosPA) Research
Excellence Initiative in Taiwan, AMiBA $-$ a 19-element dual-channel 85-105 GHz
interferometer array is being specifically built to search for high redshift
clusters of galaxies via the Sunyaev-Zeldovich Effect (SZE). In addition, AMiBA
will have full polarization capabilities, in order to probe the polarization
properties of the Cosmic Microwave Background. AMiBA, to be sited on Mauna Kea
in Hawaii or in Chile, will reach a sensitivity of $\sim 1$ mJy or 7$\mu$K in 1
hour. The project involves extensive international scientific and technical
collaborations. The construction of AMiBA is scheduled to starting operating in
early 2004.

</DOC>
<DOC>
<DOCNO> 117663 </DOCNO>
Delta Scuti Stars in Stellar Systems: a Review


  We present a list of delta Scuti stars in double and multiple systems,
ranging from the very wide binaries to the very close ones such as
spectroscopic and eclipsing systems including the optical visual pairs which
are of no further use here. Our aim is to group the information from the
binarity on the one hand and the pulsational characteristics on the other hand
for as complete a sample as possible of delta Scuti stars in stellar systems. A
selection of 18 well-documented cases, taking care that every type of binary is
being represented, is discussed more extensively.

</DOC>
<DOC>
<DOCNO> 120637 </DOCNO>
BeppoSAX Observations of Markarian 501 in June 1999


  We present the preliminary results of a long BeppoSAX observation of the BL
Lac object Mkn501 carried out in June 1999. The source was fainter than found
during the BeppoSAX pointings of 1997 and 1998, but is still detected with a
good signal-to-noise ratio up to ~40 keV. The X-ray spectrum in the energy
range 0.1-40 keV, produced through synchrotron radiation, is steeper than in
the previous years, it is clearly curved, and peaks (in nu*F_nu) at ~0.5 keV.
This energy is much lower than those at which the synchrotron component was
found to peak in 1997 and 1998. Some intraday variability suggests that
activity of the source on small time scales accompanies the large long time
scale changes of brightness and spectrum.

</DOC>
<DOC>
<DOCNO> 83307 </DOCNO>
ATLAS: A flexible and extensible architecture for linguistic annotation


  We describe a formal model for annotating linguistic artifacts, from which we
derive an application programming interface (API) to a suite of tools for
manipulating these annotations. The abstract logical model provides for a range
of storage formats and promotes the reuse of tools that interact through this
API. We focus first on ``Annotation Graphs,'' a graph model for annotations on
linear signals (such as text and speech) indexed by intervals, for which
efficient database storage and querying techniques are applicable. We note how
a wide range of existing annotated corpora can be mapped to this annotation
graph model. This model is then generalized to encompass a wider variety of
linguistic ``signals,'' including both naturally occuring phenomena (as
recorded in images, video, multi-modal interactions, etc.), as well as the
derived resources that are increasingly important to the engineering of natural
language processing systems (such as word lists, dictionaries, aligned
bilingual corpora, etc.). We conclude with a review of the current efforts
towards implementing key pieces of this architecture.

</DOC>
<DOC>
<DOCNO> 169966 </DOCNO>
Singlet aided infinite resource reduction in the comparison of distant


  We present a task which can be faithfully solved with finite resources only
when aided by particles prepared in a particular entangled state: the singlet
state. The task consists of identifying the mutual parallelity or orthogonality
of weak distant magnetic fields whose absolute directions are completely
unknown.

</DOC>
<DOC>
<DOCNO> 150816 </DOCNO>
Renormalization of QED with planar binary trees


  The renormalized photon and electron propagators are expanded over planar
binary trees. Explicit recurrence solutions are given for the terms of these
expansions. In the case of massless Quantum Electrodynamics (QED), the relation
between renormalized and bare expansions is given in terms of a Hopf algebra
structure. For massive quenched QED, the relation between renormalized and bare
expansions is given explicitly.

</DOC>
<DOC>
<DOCNO> 39901 </DOCNO>
The Scientific Need for a Scalar/Higgs Factory


  The scalar sector of the electroweak theory can be probed by a mu^+mu^-
collider S channel resonance machine. We give arguments for when such a machine
may be needed and when this information could be obtained by the LHC detector.
A very interesting case is the possibility that several scalar particles are in
the same mass range for the supersymmetric Higgs bosons h, H, and A, which
would definitely require such a machine. The Higgs factory could follow the
construction of a neutrino factory.

</DOC>
<DOC>
<DOCNO> 10094 </DOCNO>
On the Theory of a New Maximum Observed in dc Transport in Modulated


  We propose a theory for the new maximum recently observed by Willett et al
[1] in the longitudinal magnetoresistance of a weakly modulated two-dimensional
electron gas (2DEG) near filling factor \nu =1/2 for the current driven along
the modulation lines. The maximum is superimposed upon a new resonance
structure. This occurs due to the geometric resonance of composite fermion
cyclotron orbits with the period of modulation of the effective magnetic field.
We propose here a semiquantitative theory of the dc magnetotransport in a
modulated 2DEG near one half filling. Our analysis is based on the Boltzmann
transport equation and it enables us to obtain this maximum which was neither
observed nor predicted previously.

</DOC>
<DOC>
<DOCNO> 119514 </DOCNO>
Coronal Line Emission from NLS1s


  We discuss the optical coronal line spectra observed for a sample of 19
Narrow-Line Seyfert 1 galaxies. We find no correlation between the coronal line
strength and the soft X-ray power-law index derived from ROSAT PSPC data. There
is a trend for broader coronal lines to have larger equivalent widths. In
addition, a strong trend is found between line width and velocity relative to
the NLR. This trend is interpreted in terms of a decelerating outflow,
originating close to the nucleus.

</DOC>
<DOC>
<DOCNO> 170046 </DOCNO>
Aspects of nonlocality in atom-photon interactions in a cavity


  We investigate a Bell-type inequality for probabilities of detected atoms
formulated using atom-photon interactions in a cavity. We consider decoherence
brought about by both atomic decay, as well as cavity photon loss, and study
its quantitative action in diminishing the atom-field and the resultant
atom-atom secondary correlations. We show that the effects of decoherence on
nonlocality can be observed in a controlled manner in actual experiments
involving the micromaser and also the microlaser.

</DOC>
<DOC>
<DOCNO> 150845 </DOCNO>
Polarization-Free Generators and the S-Matrix


  Polarization-free generators, i.e. ``interacting'' Heisenberg operators which
are localized in wedge-shaped regions of Minkowski space and generate single
particle states from the vacuum, are a novel tool in the analysis and synthesis
of two-dimensional integrable quantum field theories. In the present article,
the status of these generators is analyzed in a general setting. It is shown
that such operators exist in any theory and in any number of spacetime
dimensions. But in more than two dimensions they have rather delicate domain
properties in the presence of interaction. If, for example, they are defined
and temperate on a translation-invariant, dense domain, then the underlying
theory yields only trivial scattering. In two-dimensional theories, these
domain properties are consistent with non-trivial interaction, but they exclude
particle production. Thus the range of applications of polarization-free
generators seems to be limited to the realm of two-dimensional theories.

</DOC>
<DOC>
<DOCNO> 119718 </DOCNO>
Polarized Sub-Millimetre Emission from Filamentary Molecular Clouds


  We model the sub-millimetre polarization patterns that are expected for
filamentary clouds that are threaded by helical magnetic fields. We previously
developed a three parameter model of such clouds (Fiege & Pudritz 2000a), which
are described by a concentration parameter $C$, and two flux to mass ratios
$\Gz$ and $\Gphi$ to specify the mass loading of the poloidal and toroidal
field lines respectively. Our models provide a simple and purely geometric
explanation for the well-known ``polarization hole'' effect, in which the
sub-millimetre polarization percentage decreases toward the regions of peak
intensity. This occurs because of a cancellation between contributions to the
polarization from the ``backbone'' of poloidal flux along the filament's axis
and its surrounding envelope, which is dominated by the toroidal field
component. A systematic exploration of our parameter space allows us to
classify the polarization patterns due to filaments aligned approximately
perpendicular to the plane of the sky into three basic types. The polarization
vectors are parallel to filaments when $\ratio\appleq 0.1$, where $\Bzs$ and
$\Bphis$ are respectively the poloidal and toroidal magnetic field components
at the outer surface of the filament. The polarization vectors are
perpendicular to filaments when $\ratio\appgeq 0.33$. Intermediate cases result
in polarization patterns that contain $90^\circ$ flips in the orientation of
the polarization vectors. The flips are symmetric about the central axis for
filaments oriented parallel to the plane of the sky, but more complicated
asymmetric patters result from filaments that are inclined at some angle.

</DOC>
<DOC>
<DOCNO> 80746 </DOCNO>
Spectrum of the U(1) staggered Dirac operator in four dimensions


  We compare the low-lying spectrum of the staggered Dirac operator in the
confining phase of compact U(1) gauge theory on the lattice to predictions of
chiral random matrix theory. The small eigenvalues contribute to the chiral
condensate similar as for the SU(2) and SU(3) gauge groups. Agreement with the
chiral unitary ensemble is observed below the Thouless energy, which is
extracted from the data and found to scale with the lattice size according to
theoretical predictions.

</DOC>
<DOC>
<DOCNO> 69382 </DOCNO>
New model for the neutrino mass matrix


  I suggest a model based on a softly broken symmetry L_e - L_mu - L_tau and on
Babu's mechanism for two-loops radiative generation of the neutrino masses. The
model predicts that one of the physical neutrinos (nu_3) is massless and that
its component along the nu_e direction (U_e3) is zero. Moreover, if the
soft-breaking term is assumed to be very small, then the vacuum oscillations of
nu_e have almost maximal amplitude and solve the solar-neutrino problem. New
scalars are predicted in the 10 TeV energy range, and a breakdown of e-mu-tau
universality should not be far from existing experimental bounds.

</DOC>
<DOC>
<DOCNO> 8538 </DOCNO>
Experimental fitting to the bipolaronic model of the normal-state


  Normal-state resistance data from Bi_2Sr_2CaCu_2O_8 single crystals were
fitted to the (bi)polaronic conduction model, $R=R_0 (T+\sigma_b T^2)/(1+bT)$,
with satisfactory agreement over a wide temperature range. The fluctuating
conduction region is found to be much narrower than that in the usual sense, as
is the case for a charged Bose-gas. We estimate the effective (bi)polaron mass
to be ~ 4m_e.

</DOC>
<DOC>
<DOCNO> 70467 </DOCNO>
QCD in a Finite Volume


  We will review our understanding of non-abelian gauge theories in finite
physical volumes. It allows one in a reliable way to trace some of the
non-perturbative dynamics. The role of gauge fixing ambiguities related to
large field fluctuations is an important lesson that can be learned. The
hamiltonian formalism is the main tool, partly because semiclassical techniques
are simply inadequate once the coupling becomes strong. Using periodic boundary
conditions, continuum results can be compared to those on the lattice. Results
in a spherical finite volume will be discussed as well.

</DOC>
<DOC>
<DOCNO> 69452 </DOCNO>
QCD sum rules as applied to heavy baryons


  We give an overview over recent calculations of baryonic correlator functions
with finite mass quarks in view on their applicability for QCD sum rules. The
QCD sum rule method is then demonstrated within the Heavy Quark Effective
Theory.

</DOC>
<DOC>
<DOCNO> 70002 </DOCNO>
The b->sgamma decay rate in NLO, Higgs boson limits, and LSP masses in


  New NLO b->sgamma calculations have become available. We observe that at
large tanbeta the dominant NLO term of the chargino amplitude, which is
proportional to mu.tanbeta^2, changes the sign of this amplitude in a large
region of the CMSSM parameter space, so that the preferred sign of the Higgs
mixing parameter mu now agrees with the preferred sign of b-tau unification. We
find that the b->sgamma rate does not constrain the CMSSM anymore, if the
higher order contributions and its uncertainties from the incomplete
calculations are taken into account.
  The Higgs boson mass in the CMSSM is found to be between 110 and 120 GeV for
a top mass of 175 GeV, if the Higgs mass limit of 107.9 GeV from LEP, which
implies tanbeta>3.3, is taken into account The mean Higgs boson mass value and
its dominant errors are: m_h=115\pm 3(stop mass) \pm 1.5(stop mixing) \pm
2(theory) \pm 5(top mass) GeV. This Higgs mass range is valid for all tanbeta
values above 20 and decreases for lower tanbeta. If the presently claimed
evidence for dark matter by the DAMA Collaboration is interpreted as the
Lightest Supersymmetric Particle (LSP) of the CMSSM, then it is at the edge of
the parameter space allowed by the present Higgs limit of 107.9 GeV from LEP.

</DOC>
<DOC>
<DOCNO> 10325 </DOCNO>
Ballistic reflection at a side-gate in a


  We have fabricated a sub-micron-sized structure consisting of an InAs-based
2DEG, two narrow Nb leads and a gate, where the indirect ballistic transport
between the non-oppositely superconducting contacts can be controlled by the
voltage applied to the gate. This new kind of tuneable junction can be used for
applications and allows several fundamental questions related to the transport
mechanism to be studied. First results of experiments carried out in this
respect are presented.

</DOC>
<DOC>
<DOCNO> 11974 </DOCNO>
Persistence in higher dimensions : a finite size scaling study


  We show that the persistence probability $P(t,L)$, in a coarsening system of
linear size $L$ at a time $t$, has the finite size scaling form $P(t,L)\sim
L^{-z\theta}f(\frac{t}{L^{z}})$ where $\theta$ is the persistence exponent and
$z$ is the coarsening exponent. The scaling function $f(x)\sim x^{-\theta}$ for
$x \ll 1$ and is constant for large $x$. The scaling form implies a fractal
distribution of persistent sites with power-law spatial correlations. We study
the scaling numerically for Glauber-Ising model at dimension $d = 1$ to 4 and
extend the study to the diffusion problem. Our finite size scaling ansatz is
satisfied in all these cases providing a good estimate of the exponent
$\theta$.

</DOC>
<DOC>
<DOCNO> 69483 </DOCNO>
Determination of the Delta++ magnetic dipole moment


  We study the elastic and radiative pi+ p scattering within a full dynamical
model which incorporates the finite width effects of the Delta++. The
scattering amplitudes are invariant under contact transformations of the spin
3/2 field and gauge-invariance is fulfilled for the radiative case. The pole
parameters of the Delta++ obtained from the elastic cross section are m_Delta =
1211.2 \pm 0.4 MeV and Gamma_Delta = 88.2 \pm 0.4 MeV. From a fit to the most
sensitive observables in radiative pi+ p scattering, we obtain mu_Delta = 6.14
\pm 0.51 e/2m_p for the magnetic dipole moment of the Delta++.

</DOC>
<DOC>
<DOCNO> 10626 </DOCNO>
Distance-depending electron-phonon interactions


  For a dimer with a non-degenerate orbital built from atomic wave functions of
Gaussian shape we evaluate all the electron-phonon couplings derived from the
one-body and two-body electronic interactions, considering both the adiabatic
and extreme non-adiabatic limit. Not only the values of the coupling parameters
in the two limits, but also the expressions of the corresponding terms in the
Hamiltonian differ.
 Depending on the distance between the dimer ions, some of the two-body
couplings are comparable, or even larger than the one-body ones.

</DOC>
<DOC>
<DOCNO> 151296 </DOCNO>
Microscopic Pictures of Dynamical Symmetry Breaking in Supersymmetric


  Several distinct mechanisms of confinement and dynamical symmetry breaking
(DSB) are identified, in a class of supersymmetric $SU(n_c)$, $USp(2n_c)$ and
$SO(n_c)$ gauge theories. In some of the vacua, the magnetic monopoles carrying
nontrivial flavor quantum numbers condense, causing confinement and symmetry
breaking simultaneously. In more general classes of vacua, however, the
effective low-energy degrees of freedom are found to be constituents of the
monopoles - dual (magnetic) quarks. These magnetic quarks condense and give
rise to confinement and DSB. We find two more important classes of vacua, one
is in various universality classes of nontrivial superconformal theories
(SCFT), another in free-magnetic phase.

</DOC>
<DOC>
<DOCNO> 116852 </DOCNO>
Quantum string field theory and psychophysics


  The quantum string field theoretic structure of interactive phenomena is
discussed

</DOC>
<DOC>
<DOCNO> 102757 </DOCNO>
The eta-invariant, Maslov index, and spectral flow for Dirac-type


  Several proofs have been published of the Mod Z gluing formula for the
eta-invariant of a Dirac operator. However, so far the integer contribution to
the gluing formula for the eta-invariant is left obscure in the literature. In
this article we present a gluing formula for the eta-invariant which expresses
the integer contribution as a triple index involving the boundary conditions
and the Calderon projectors of the two parts of the decomposition. The main
ingredients of our presentation are the Scott-Wojciechowski theorem for the
determinant of a Dirac operator on a manifold with boundary and the approach of
Bruning-Lesch to the mod Z gluing formula.
  Our presentation includes careful constructions of the Maslov index and
triple index in a symplectic Hilbert space. As a byproduct we give intuitively
appealing proofs of two theorems of Nicolaescu on the spectral flow of Dirac
operators.
  As an application of our methods, we carry out a detailed analysis of the
eta-invariant of the odd signature operator coupled to a flat connection using
adiabatic methods. This is used to extend the definition of the
Atiyah-Patodi-Singer rho-invariant to manifolds with boundary. We derive a
``non-additivity'' formula for the Atiyah-Patodi-Singer rho-invariant and
relate it to Wall's non-additivity formula for the signature of
even-dimensional manifolds.

</DOC>
<DOC>
<DOCNO> 85131 </DOCNO>
Accelerating Universes with Scaling Dark Matter


  Friedmann-Robertson-Walker universes with a presently large fraction of the
energy density stored in an $X$-component with $w_X<-1/3$, are considered. We
find all the critical points of the system for constant equations of state in
that range. We consider further several background quantities that can
distinguish the models with different $w_X$ values. Using a simple toy model
with a varying equation of state, we show that even a large variation of $w_X$
at small redshifts is very difficult to observe with $d_L(z)$ measurements up
to $z\sim 1$. Therefore, it will require accurate measurements in the range
$1<z<2$ and independent accurate knowledge of $\Omega_{m,0}$ (and/or
$\Omega_{X,0}$) in order to resolve a variable $w_X$ from a constant $w_X$.

</DOC>
<DOC>
<DOCNO> 121214 </DOCNO>
Gravitational Collapse in Turbulent Molecular Clouds. II.


  Hydrodynamic supersonic turbulence can only prevent local gravitational
collapse if the turbulence is driven on scales smaller than the local Jeans
lengths in the densest regions, a very severe requirement (Paper I). Magnetic
fields have been suggested to support molecular clouds either magnetostatically
or via magnetohydrodynamic (MHD) waves. Whereas the first mechanism would form
sheet-like clouds, the second mechanism not only could exert a pressure onto
the gas counteracting the gravitational forces, but could lead to a transfer of
turbulent kinetic energy down to smaller spatial scales via MHD wave
interactions. This turbulent magnetic cascade might provide sufficient energy
at small scales to halt local collapse.
  We test this hypothesis with MHD simulations at resolutions up to 256^3
zones, done with ZEUS-3D. We first derive a resolution criterion for
self-gravitating, magnetized gas: in order to prevent collapse of
magnetostatically supported regions due to numerical diffusion, the minimum
Jeans length must be resolved by four zones. Resolution of MHD waves increases
this requirement to roughly six zones. We then find that magnetic fields cannot
prevent local collapse unless they provide magnetostatic support. Weaker
magnetic fields do somewhat delay collapse and cause it to occur more uniformly
across the supported region in comparison to the hydrodynamical case. However,
they still cannot prevent local collapse for much longer than a global
free-fall time.

</DOC>
<DOC>
<DOCNO> 39934 </DOCNO>
Run II Jet Physics: Proceedings of the Run II QCD and Weak Boson Physics


  The Run II jet physics group includes the Jet Algorithms, Jet Shape/Energy
Flow, and Jet Measurements/Correlations subgroups. The main goal of the jet
algorithm subgroup was to explore and define standard Run II jet finding
procedures for CDF and DO. The focus of the jet shape/energy flow group was the
study of jets as objects and the energy flows around these objects. The jet
measurements/correlations subgroup discussed measurements at different beam
energies; strong coupling constant measurements; and LO, NLO, NNLO, and
threshold jet calculations. As a practical matter the algorithm and
shape/energy flow groups merged to concentrate on the development of Run II jet
algorithms that are both free of theoretical and experimental difficulties and
able to reproduce Run I measurements.
        Starting from a review of the experience gained during Run I, the group
considered a variety of cone algorithms and KT algorithms. The current
understanding of both types of algorithms, including calibration issues, are
discussed in this report along with some preliminary experimental results. The
jet algorithms group recommends that CDF and DO employ the same version of both
a cone algorithm and a KT algorithm during Run II. Proposed versions of each
type of algorithm are discussed. The group also recommends the use of full
4-vector kinematic variables whenever possible. The recommended algorithms
attempt to minimize the impact of seeds in the case of the cone algorithm and
preclustering in the case of the KT algorithm. Issues regarding precluster
definitions and merge/split criteria require further study.

</DOC>
<DOC>
<DOCNO> 8178 </DOCNO>
Upper critical field in layered superconductors


  The theoretical statements about a restoration of a superconductivity at
magnetic fields higher than the quasiclassical upper critical field and a
reentrance of superconductivity at temperatures $T_c(H)\approx T_c(0)$ in the
superconductors with open Fermi surfaces are reinvestigated taking into account
a scattering of quasiparticles on the impurities.
  The system of integral equations for determination of the upper critical
field parallel to the conducting planes in a layered conventional and
unconventional superconductors with impurities are derived. The $H_{c2}(T)$
values for the "clean" case in the Ginzburg-Landau regime and at any
temperature in the "dirty" case are found analytically. The upper limit of the
superconductor purity when the upper critical field definately has a finite
value is established.

</DOC>
<DOC>
<DOCNO> 102382 </DOCNO>
Scattering Theory Approach to Random Schroedinger Operators in One


  Methods from scattering theory are introduced to analyze random Schroedinger
operators in one dimension by applying a volume cutoff to the potential. The
key ingredient is the Lifshitz-Krein spectral shift function, which is related
to the scattering phase by the theorem of Birman and Krein. The spectral shift
density is defined as the "thermodynamic limit" of the spectral shift function
per unit length of the interaction region. This density is shown to be equal to
the difference of the densities of states for the free and the interacting
Hamiltonians. Based on this construction, we give a new proof of the Thouless
formula. We provide a prescription how to obtain the Lyapunov exponent from the
scattering matrix, which suggest a way how to extend this notion to the higher
dimensional case. This prescription also allows a characterization of those
energies which have vanishing Lyapunov exponent.

</DOC>
<DOC>
<DOCNO> 178744 </DOCNO>
Final State Interaction in Exclusive $(e,e'NN)$ Reactions


  Contributions of nucleon-nucleon (NN) correlations, meson exchange currents
and the residual final state interactions (FSI) on exclusive two-nucleon
knock-out reactions induced by electron scattering are investigated. All
contributions are derived from the same realistic meson exchange model for the
NN interaction. Effects of correlations and FSI are determined in a consistent
way by solving the NN scattering equation, the Bethe-Goldstone equation, for
two nucleons in nuclear matter. One finds that the FSI re-scattering terms are
non-negligible even if the two nucleons are emitted back to back.

</DOC>
<DOC>
<DOCNO> 83240 </DOCNO>
On the Development of the Intersection of a Plane with a Polytope


  Define a ``slice'' curve as the intersection of a plane with the surface of a
polytope, i.e., a convex polyhedron in three dimensions. We prove that a slice
curve develops on a plane without self-intersection. The key tool used is a
generalization of Cauchy's arm lemma to permit nonconvex ``openings'' of a
planar convex chain.

</DOC>
<DOC>
<DOCNO> 39841 </DOCNO>
Behavior of the diffractive cross section in hadron-nucleus collisions


  A phenomenological analysis of diffractive dissociation of nuclei in
proton-nucleus and meson-nucleus collisions is presented. The theoretical
approach employed here is able to take into account at once data of the HELIOS
and EHS/NA22 collaborations that exhibit quite different atomic mass
dependences. Possible extensions of this approach to hard diffraction in
nuclear processes are also discussed.

</DOC>
<DOC>
<DOCNO> 119727 </DOCNO>
Modelling Radioactivities and other Observables from OB Associations


  Recent observations of the diffuse Galactic gamma-ray glow at 1.809 MeV,
attributed to the radioactive decay of 26Al, point towards a massive star
origin of this radioactive isotope. Wolf Rayet stars and core-collapse
supernovae appear to dominate the production of this isotope. Massive stars are
commonly located in clusters and OB associations, regions of recent star
formation. We thus discuss the temporal evolution of 26Al, and 60Fe within
evolving OB associations. The goal of this study is to utilize the associated
gamma-ray lines as a diagnostic tool for the study of correlated star
formation, and also to provide more detailed models for the interpretation of
data obtained with COMPTEL on the Compton Observatory. We investigate the
effects of possible aluminum yield enhancements, predicted for some massive
close binary systems. In addition to the ejection of chemically processed
matter, massive stars also drive strong stellar winds and emit large fluxes of
ionizing radiation. This energy and radiation input into the interstellar
medium (ISM) is crucial for the dynamical evolution of the gas and subsequent
star forming activity in the galactic disk. We discuss population synthesis
models for a variety of star formation histories, and compare the predicted
gamma-ray line lightcurves to COMPTEL measurements in the Cygnus region.
Radioactive tracers such as 26Al and 60Fe provide a unique gamma-ray tracer of
Galactic star formation activity, complementary to other methods using spectral
information in the radio, IR or optical bands.

</DOC>
<DOC>
<DOCNO> 8235 </DOCNO>
Nonlinear analysis of the shearing instability in granular gases


  It is known that a finite-size homogeneous granular fluid develops an
hydrodynamic-like instability when dissipation crosses a threshold value. This
instability is analyzed in terms of modified hydrodynamic equations: first, a
source term is added to the energy equation which accounts for the energy
dissipation at collisions and the phenomenological Fourier law is generalized
according to previous results. Second, a rescaled time formalism is introduced
that maps the homogeneous cooling state into a nonequilibrium steady state. A
nonlinear stability analysis of the resulting equations is done which predicts
the appearance of flow patterns. A stable modulation of density and temperature
is produced that does not lead to clustering. Also a global decrease of the
temperature is obtained, giving rise to a decrease of the collision frequency
and dissipation rate. Good agreement with molecular dynamics simulations of
inelastic hard disks is found for low dissipation.

</DOC>
<DOC>
<DOCNO> 101833 </DOCNO>
On the volume conjecture for hyperbolic knots


  In this article, we give a rough, and so not complete yet, proof of Kashaev's
conjecture, that is, the volume conjecture for hyperbolic knots, where the
hyperbolicity equations associated to knot diagrams appear as the stationary
phase equations for Kashaev's invariants.

</DOC>
<DOC>
<DOCNO> 69406 </DOCNO>
The INT at Age Ten


  The history of the Department of Energy's Institute for Nuclear Theory,
located on the campus of the University of Washington, is reviewed on the
occasion of the INT's tenth anniversary.

</DOC>
<DOC>
<DOCNO> 13556 </DOCNO>
Eigen-functional bosonization and Eikonal-type equations in


  With the eigen-functional bosonization method, we study one-dimensional
strongly correlated electron systems with large momentum ($2k_{F}$ and/or
$4k_{F}$) transfer term(s), and demonstrate that this kind of problems ends in
to solve the Eikonal-type equations, and these equations are universal, and
independent of whether or not the system is integrable. In contrast to usual
perturbation theory, this method is valid not only for weak electron
interaction, but also for strong electron interaction. Comparing with exact
solution of some integrable models, it can give correct results in one-loop
approximation. This method can also be used to study electron-phonon
interaction systems, and two coupled spin chain or quantum wire systems.

</DOC>
<DOC>
<DOCNO> 68186 </DOCNO>
Anomalous Flavor U(1): Predictive Texture For Bi-maximal Neutrino Mixing


  We present a scenario which naturally provides bi-maximal neutrino mixings
for a simultaneous explanation of the recent atmospheric and solar neutrino
data. A crucial role is played by an anomalous flavor ${\cal U}(1)$ symmetry,
which is also important for a natural understanding of charged fermion mass
hierarchies and magnitudes of the CKM matrix elements. Within MSSM the solar
neutrino problem can be resolved either through vacuum oscillations or the
large mixing angle MSW solution. In supersymmetric GUTs such as SU(5) and
SO(10) the MSW solution is realized. If the flavor ${\cal U}(1)$ also mediates
supersymmetry breaking, the vacuum solution in MSSM is eliminated, and only the
large mixing angle MSW solution survives.

</DOC>
<DOC>
<DOCNO> 68538 </DOCNO>
Precision Electroweak Parameters and the Higgs Mass


  The status of various precisely measured electroweak parameters is reviewed.
Natural relations among them are shown to constrain the Higgs mass, m_H, via
quantum loop effects to relatively low values. A comparison with direct Higgs
searches is made.

</DOC>
<DOC>
<DOCNO> 70381 </DOCNO>
Chiral Symmetry and the Nucleon Nucleon Interaction


  Various aspects of the application of Effective Field Theory (EFT) to the
Nucleon-Nucleon (NN) interaction are considered. We look for contributions
beyond One Pion Exchange which are predicted by Chiral Symmetry.
  Using the formalism of the Wilson Renormalisation Group (RG) we review power
counting in a simplified EFT containing only nucleons. For weak scattering at
low energy, we find a natural expansion of the scattering matrix around the
unique trivial fixed point of the RG. For strong scattering at low energy, the
calculation can be organised in a useful and systematic way by expanding the
potential around a non-trivial fixed point corresponding to a bound state of
two nucleons at threshold. The resulting expansion of the inverse of the
scattering matrix reproduces the effective range expansion order by order.
  The extension of this EFT to include pions in a manner consistent with chiral
symmetry is discussed. By considering a modified effective range expansion, we
find that the small momentum expansion in S-wave scattering converges slowly,
if at all. The NN potential is written down to third order in small momenta.
With a cut-off in coordinate space, we calculate phase shifts in peripheral
partial waves for which the EFT predictions are parameter-free, and for which
we may use the expansion around the trivial fixed point. We find several
partial waves in which the effects of two-pion exchange can be isolated, but no
strong evidence is found for the convergence of the small momentum expansion at
this order.

</DOC>
<DOC>
<DOCNO> 122179 </DOCNO>
On the way to global phase-delay astrometry


  The use of the phase-delay improves substantially the accuracy obtained in
VLBI astrometry with respect to the group-delay observable. Recently, Ros et
al. (1999) have extended the related phase-connection technique to a triangle
of radio sources with relative separations up to 6.8deg (the S5 sources
BL1803+784/ QSO1928+738/ BL2007+777). This technique has also been extended for
separations up to 15deg in the studies of the pair of S5 radio sources
QSO1150+812/ BL1803+784 (Perez-Torres et al. 2000). We are carrying out a
long-term astrometric programme at 8.4, 15, and 43 GHz to determine the
absolute kinematics of radio source components in the 13 members of the
complete S5 polar cap sample. For each epoch, all the radio sources are
observed at the same frequency for 24 hours in total. Bootstrapping techniques
are used to phase-connect the data jointly for the 13 objects throughout the
observations. An accurate registration of the maps of the radio sources at
different frequencies will allow a study of jet components with unprecedented
precision and provide spectral information. This observing scheme could be
extended in the future to other regions of the sky and eventually lead to
global phase-delay astrometry.

</DOC>
<DOC>
<DOCNO> 84292 </DOCNO>
The Cauchy Problem for the Einstein Equations


  Various aspects of the Cauchy problem for the Einstein equations are
surveyed, with the emphasis on local solutions of the evolution equations.
Particular attention is payed to giving a clear explanation of conceptual
issues which arise in this context. The question of producing reduced systems
of equations which are hyperbolic is examined in detail and some new results on
that subject are presented. Relevant background from the theory of partial
differential equations is also explained at some length

</DOC>
<DOC>
<DOCNO> 70961 </DOCNO>
Next-to-leading order Calculation of a Fragmentation Function in a


  Next-to-leading order corrections to fragmentation functions in a light-cone
gauge are discussed. This gauge simplifies the calculation by eliminating many
Feynman diagrams at the expense of introducing spurious poles in loop
integrals. As an application, the short-distance coefficients for the
color-octet $^3S_1$ term in the fragmentation function for a gluon to split
into polarized heavy quarkonium states are re-calculated to order $\alpha_s^2$.
We show that the ill-defined spurious poles cancel and the appropriate
prescriptions for the remaining spurious poles can be determined by calculating
a subset of the diagrams in the Feynman gauge. Our answer agrees with the
recent calculation of Braaten and Lee in the Feynman gauge, but disagrees with
another previous calculation.

</DOC>
<DOC>
<DOCNO> 68626 </DOCNO>
Pion propagation in the linear sigma model at finite temperature


  We construct effective one-loop vertices and propagators in the linear sigma
model at finite temperature, satisfying the chiral Ward identities and thus
respecting chiral symmetry, treating the pion momentum, pion mass and
temperature as small compared to the sigma mass. We use these objects to
compute the two-loop pion self-energy. We find that the perturbative behavior
of physical quantities, such as the temperature dependence of the pion mass, is
well defined in this kinematical regime in terms of the parameter
m_pi^2/4pi^2f_pi^2 and show that an expansion in terms of this reproduces the
dispersion curve obtained by means of chiral perturbation theory at leading
order. The temperature dependence of the pion mass is such that the first and
second order corrections in the above parameter have the same sign. We also
study pion damping both in the elastic and inelastic channels to this order and
compute the mean free path and mean collision time for a pion traveling in the
medium before forming a sigma resonance and find a very good agreement with the
result from chiral perturbation theory when using a value for the sigma mass of
600 MeV.

</DOC>
<DOC>
<DOCNO> 118562 </DOCNO>
Disk heating and stellar migration in galaxies


  The paper claimed that significant radial migration of stars in a stellar
disk like that of the Milky Way could not occur. We now think that while the
treatment of the effects of molecular clouds was correct, the paper seriously
underestimated the ability of spiral arms to shift the radii of stars that
corotate with them. Consequently, it is likely that significant radial
migration_is_ possible.

</DOC>
<DOC>
<DOCNO> 10832 </DOCNO>
Effect of colloidal charge discretization in the primitive model


  The effect of fixed discrete colloidal charges in the primitive model is
investigated for spherical macroions. Instead of considering a central bare
charge, as it is traditionally done, we distribute \textit{discrete} charges
randomly on the sphere. We use molecular dynamics simulations to study this
effect on various properties such as overcharging, counterion distribution and
diffusion. In the vicinity of the colloid surface the electrostatic potential
may considerably differ from the one obtained with a central charge. In the
strong Coulomb coupling, we showed that the colloidal charge discretization
qualitatively influences the counterion distribution and leads to a strong
colloidal charge-counterion pair association. However, we found that
\textit{charge inversion} still persists even if strong pair association is
observed.

</DOC>
<DOC>
<DOCNO> 84399 </DOCNO>
Asymptotic expansions for relativistic celestial mechanics


  The method of asymptotic expansions is used to build an approximation scheme
relevant to celestial mechanics in relativistic theories of gravitation. A
scalar theory is considered, both as a simple example and for its own sake.
This theory is summarized, then the relevant boundary problem is seen to be the
full initial-value problem. It is shown that, with any given system of
gravitating bodies, one may associate a one-parameter family of similar
systems, the parameter measuring the gravitational field-strength. After a
specific change of units, the derivation of asymptotic expansions becomes
straightforward. Two hypotheses could be made as to which time variable has to
be used in the expansion. The first one leads to an "asymptotic" post-Newtonian
approximation (PNA) with instantaneous propagation, differing from the standard
PNA in that, in the asymptotic PNA, all fields are expanded. The second
hypothese could lead to an "asymptotic" post-Minkowskian approximation (PMA)
allowing to describe propagation effects, but it is not compatible with the
Newtonian limit. It is shown that the standard PNA is not compatible with the
application of the usual method of asymptotic expansions as envisaged here.

</DOC>
<DOC>
<DOCNO> 170359 </DOCNO>
Off Resonant Pumping for Transition from Continuous to Discrete Spectrum


  We show that in parametrically driven systems and, more generally, in systems
in coherent states, off-resonant pumping can cause a transition from a
continuum energy spectrum of the system to a discrete one, and result in
quantum revivals of the initial state. The mechanism responsible for quantum
revivals in the present case is different from that in the non-linear
wavepacket dynamics of systems such as Rydberg atoms. We interpret the reported
phenomena as an optical analog of Bloch oscillations realized in Fock space and
propose a feasible scheme for inducing Bloch oscillations in trapped ions.

</DOC>
<DOC>
<DOCNO> 99879 </DOCNO>
The global indices of log Calabi-Yau varieties --A supplement to


  This paper gives the all possible global indices of log Calabi-Yau 3-folds
with standard coefficients on the boundaries and having lc, non-klt
singularities. This follows easily from the discussion in the paper: The
indices of log canonical singularities by Fujino (AG/9909035).

</DOC>
<DOC>
<DOCNO> 68812 </DOCNO>
Yang-Mills- and D-instantons


  In these lectures, which are written at an elementary and pedagogical level,
we discuss general aspects of (single) instantons in SU(N_c) Yang-Mills theory,
and then specialize to the case of N = 4 supersymmetry and the large N_c limit.
We show how to determine the measure of collective coordinates and compute
instanton corrections to certain correlation functions. We then relate this to
D-instantons in type IIB supergravity. By taking the D-instantons to live in an
$AdS_5\times S^5$ background, we perform explicit checks of the AdS/CFT
correspondence.

</DOC>
<DOC>
<DOCNO> 13251 </DOCNO>
Correlated Polarons in Dissimilar Perovskite Manganites


  We report x-ray scattering studies of broad peaks located at a (0.5 0 0)/(0
0.5 0)-type wavevector in the paramagnetic insulating phases of
La_{0.7}Ca_{0.3}MnO_{3} and Pr_{0.7}Ca_{0.3}MnO_{3}. We interpret the
scattering in terms of correlated polarons and measure isotropic correlation
lengths of 1-2 lattice constants in both samples. Based on the wavevector and
correlation lengths, the correlated polarons are found to be consistent with
CE-type bipolarons. Differences in behavior between the samples arise as they
are cooled through their respective transition temperatures and become
ferromagnetic metallic (La_{0.7}Ca_{0.3}MnO_{3}) or charge and orbitally
ordered insulating (Pr_{0.7}Ca_{0.3}MnO_{3}). Since the primary difference
between the two samples is the trivalent cation size, these results illustrate
the robust nature of the correlated polarons to variations in the relative
strength of the electron-phonon coupling, and the sensitivity of the
low-temperature ground state to such variations.

</DOC>
<DOC>
<DOCNO> 99277 </DOCNO>
Tactics, dialectics, representation theory


  This article is devoted to the tactical game theoretical interpretation of
dialectics. Dialectical games are considered as abstractly as well as models of
the internal dialogue and reflection. The models related to the representation
theory (representative dynamics) are specially investigated in detail, they
correlate with the hypothesis on the dialectical features of human thinking in
general and mathematical thought (the constructing of a solution of
mathematical problem) in particular.

</DOC>
<DOC>
<DOCNO> 40491 </DOCNO>
Jet energy scale setting with "photon+Jet" events at LHC energies.


  "photon+Jet" events, based on the q~q-> g+photon and qg-> q+photon
subprocesses, are proposed for jet energy scale setting and hadron calorimeter
calibration at LHC energies. General features and selection criteria of
"photon+Jet" events that would provide a good photon Pt - jet Pt balance are
described. CMS detector geometry is taken as the basement.

</DOC>
<DOC>
<DOCNO> 72237 </DOCNO>
On the $\sigma_L/\sigma_T$ Ratio in Polarized Vector Meson


  We study the spin-dependent cross-sections of vector meson photoproduction
for longitudinally and transversely polarized photons within a QCD- model. The
dependence of the $\sigma_T/\sigma_L$ ratio on the photon virtuality and on the
meson wave function is analysed.

</DOC>
<DOC>
<DOCNO> 40565 </DOCNO>
Jet energy scale setting with "photon+Jet" events at LHC energies.


  In this paper the study of "photon+Jet" events is continued and the event
number determination useful for jet energy scale setting with the possible CMS
detector hadron calorimeter calibration at LHC is fulfiled. The sources of
photon Pt and jet Pt disbalance are exposed. It is shown that the cluster Pt
limitation, which is found in an event outside of the jet, can be a good
criterion for this disbalance decreasing.

</DOC>
<DOC>
<DOCNO> 9401 </DOCNO>
A Two-Species Exclusion Model With Open Boundaries: A use of q-deformed


  In this paper we study an one-dimensional two-species exclusion model with
open boundaries. The model consists of two types of particles moving in
opposite directions on an open lattice. Two adjacent particles swap their
positions with rate p and at the same time they can return to their initial
positions with rate q if they belong to the different types. Using the Matrix
Product Ansatz (MPA) formalism, we obtain the exact phase diagram of this model
in restricted regions of its parameter space. It turns out that the model has
two distinct phases in each region. We also obtain the exact expressions for
the current of particles in each phase.

</DOC>
<DOC>
<DOCNO> 123274 </DOCNO>
A Mid-Infrared Study of the Young Stellar Population in the NGC 2024


  We present the results of the first broadband 10.8 um survey of the NGC 2024
cluster. The mid-infrared data were combined with our previously published JHKL
photometry in order to construct spectral energy distributions for all detected
sources. The main scientific goals were to investigate the nature of the young
stellar objects (YSOs) in the cluster, and to examine the efficiency of
detecting circumstellar disk sources from near-infrared JHKL color-color
diagrams. Out of 59 sources surveyed having K-band magnitudes K < 10.5, we
detected 35 (~59%) at 10 um. Combining these detections, and upper limits for
the non-detections, with existing JHKL data, we identify 1 Class I, 6 flat
spectrum, 28 Class II and 5 Class III sources. We find a circumstellar disk
fraction for NGC 2024 of ~85% +/- 15%, which confirms earlier published
suggestions that the majority, if not all, of the stars in NGC 2024 formed with
disks, and these disks still exist at the present time. In addition, all but
one of the disk sources identified in our survey lie in the infrared excess
region of the JHKL color-color diagram for the cluster. This demonstrates that
JHKL color-color diagrams are extremely efficient in identifying YSOs with
disks. Of the 14 sources with K - L colors suggestive of protostellar objects,
\~29% are protostellar in nature, while ~7% are true Class I YSOs. This may be
due to extinction producing very red K - L colors in Class II YSOs, thus making
them appear similar in color to protostars. This suggests caution must be
applied when estimating the sizes and lifetimes of protostellar populations
within star forming regions based on K - L colors alone. Finally, we calculate
the luminosities of the Class II YSOs in NGC 2024, rho Oph and Taurus and
discuss the results.

</DOC>
<DOC>
<DOCNO> 99492 </DOCNO>
Computing special values of partial zeta functions


  We discuss computation of the special values of partial zeta functions
associated to totally real number fields. The main tool is the \emph{Eisenstein
cocycle} $\Psi $, a group cocycle for $GL_{n} (\Z )$; the special values are
computed as periods of $\Psi $, and are expressed in terms of generalized
Dedekind sums. We conclude with some numerical examples for cubic and quartic
fields of small discriminant.

</DOC>
<DOC>
<DOCNO> 100499 </DOCNO>
A Nonlinear Approximation of Operator Equation $V^{*}QV=Q$ : Nonspectral


  $V$ denote arbitrary bounded bijection on Hilbert space $H$. We try to
describe the sets of $V$-stable vectors, i.e. the set of elements $x$ of $H$
such that the sequence $\|V^N x\| (N=1,2,...)$ is bounded (we also consider
some other analogous sets). We do it in terms of one-parameter operator
equation $ Q_t=V^*(Q_t+tI)(I+tQ_t)^{-1}V, 0\leq Q$, ($t$ is real valued
parameter $0\leq t \leq 1$,$Q$ is operator to be found). Definition: for $t
\to +0$ denote $R_0:=w-limpt (I+Q_t)^{-1}, Y_0:= strong-lim tQ_t^{-1}, X_t:=
strong-lim tQ_t $ In the case of the normal $V$ it is noted that the operators
$X_0,Y_0,R_0$ define (in essential) the spectral subspaces of $V$ (with $V$
together one can consider $aV-b, b/a \not\in spectrum V$). In this article we
will show that the similar situation holds for the arbitrary bounded bijection
$V$.

</DOC>
<DOC>
<DOCNO> 119099 </DOCNO>
Radiative Precession of an Isolated Neutron Star


  Euler's equations of motion are derived exactly for a rigid, triaxial,
internally frictionless neutron star spinning down electromagnetically in
vacuo. It is shown that the star precesses, but not freely: its regular
precession relative to the principal axes of inertia couples to the component
of the radiation torque associated with the near-zone radiation fields and is
modified into an anharmonic wobble. The wobble period \tau_1 typically
satisfies \tau_1 < 10^{-2}\tau_0, where \tau_0 is the braking time-scale; the
wobble amplitude evolves towards a constant non-zero value, oscillates, or
decreases to zero, depending on the degree of oblateness or prolateness of the
star and its initial spin state; and the (negative) angular frequency
derivative d{\omega}/dt oscillates as well, exhibiting quasi-periodic spikes
for triaxial stars of a particular figure. In light of these properties, a
young, Crab-like pulsar ought to display fractional changes of order unity in
the space of a few years in its pulse profile, magnetic inclination angle, and
d{\omega}/dt. Such changes are not observed, implying that the wobble is damped
rapidly by internal friction, if its amplitude is initially large upon
crystallization of the stellar crust. If the friction is localized in the inner
and outer crusts, the thermal luminosity of the neutron star increases by a
minimum amount \Delta L = 3*10^{31} (\epsilon / 10^{-12}) (\omega / 10^3 rad
s^{-1})^2 (\tau_d / 1 yr)^{-1} erg s^{-1}, where epsilon is the ellipticity and
\tau_d is the damping time-scale, with the actual value of \Delta L determined
in part by the thermal conduction time \tau_cond. The increased luminosity is
potentially detectable as thermal X-rays lasting for a time max(tau_d,tau_cond)
following crystallization of the crust.

</DOC>
<DOC>
<DOCNO> 118284 </DOCNO>
ISO observations of the reflection nebula Ced 201: evolution of


  We present spectrophotometric imaging mid-IR observations of the reflection
nebula Ced201. Ced201 is a part of a molecular cloud illuminated by a B9.5V
star moving through it at more than 12 km/s. The spectra of Ced201 give
evidence for transformation of very small carbonaceous grains into the carriers
of the Aromatic Infrared Bands (AIBs), due to the radiation field of the
illuminating star and/or to shock waves created by its motion. These very small
grains emit mainly very broad bands and a continuum. We suggest that they are
present everywhere in the interstellar medium but can only be detected in the
mid-IR under special circumstances such as those prevailing in this reflection
nebula. The efficiency of energy conversion of stellar light into mid-infrared
emission is 7.5% for both the very small grains and the AIB carriers, and the
fraction of interstellar carbon locked in these emitters is approximately 15%.

</DOC>
<DOC>
<DOCNO> 100765 </DOCNO>
Topology of billiard problems, II


  We give topological lower bounds on the number of periodic and closed
trajectories in strictly convex smooth billiards. We use variational reduction
admitting a finite group of symmetries and apply topological approach based on
equivariant Morse and Lusternik - Schnirelman theories.
   The paper continues results published in math.DG/9911226 and math.DG/0006049

</DOC>
<DOC>
<DOCNO> 100523 </DOCNO>
A lemma on the minimal surfaces


  Stated lemma contains the assertions about isomorphism of exact m-forms and
exterior differentials of regular m-maps, of linearly harmonic m-forms and
exterior differentials of regular harmonic m-maps, of global minimal
(n-m)-surfaces and level (n-m)-surfaces of regular minimal m-maps. It hold in
n-dimensional Euclidean space.

</DOC>
<DOC>
<DOCNO> 151377 </DOCNO>
Sigma-model symmetry in orientifold models


  We investigate in the simplest compact D=4 N=1 Type IIB orientifold models
the sigma-model symmetry suggested by the proposed duality of these models to
heterotic orbifold vacua. This symmetry is known to be present at the classical
level, and is associated to a composite connection involving untwisted moduli
in the low-energy supergravity theory. In order to study possible anomalies
arising at the quantum level, we compute potentially anomalous one-loop
amplitudes involving gluons, gravitons and composite connections. We argue that
the effective vertex operator associated to the composite connection has the
same form as that for a geometric deformation of the orbifold. Assuming this,
we are able to compute the complete anomaly polynomial, and find that all the
anomalies are canceled through a Green-Schwarz mechanism mediated by twisted RR
axions, as previously conjectured. Some questions about the field theory
interpretation of our results remain open.

</DOC>
<DOC>
<DOCNO> 120186 </DOCNO>
Determinations of Key Physical Parameters Related to Classical Double


  Multi-frequency radio observations of the radio bridge of a powerful
classical double radio source can be used to determine: the beam power of the
jets emanating from the AGN; the total time the source will actively produce
jets that power large-scale radio emission; the thermal pressure of the medium
in the vicinity of the radio source; and the total mass, including dark matter,
of the galaxy or cluster of galaxies traced by the ambient gas that surrounds
the radio source. Empirical determinations of each of these quantities are
obtained and analyzed for 22 radio sources. Typical beam powers are about
$10^{45} {erg s}^{-1}$. The characteristic or total time the AGN will actively
produce a collimated outflow is estimated. Typical total lifetimes are $\sim
(10^7$ to $10^8$) years. Total masses, and mass-density profiles, similar to
those of low-redshift clusters of galaxies are obtained. Thus, some clusters of
galaxies, or cores of clusters, exist at redshifts of one to two.
  A new method of estimating the thermal pressure of the ambient gas in the
vicinity of a powerful classical double radio source is presented. This new
estimate is independent of synchrotron and inverse Compton aging arguments, and
depends only upon the properties of the radio lobe and the shape of the radio
bridge. Thermal pressures on the order of $10^{-10} {dyne cm}^{-2}$, typical of
gas in low-redshift clusters of galaxies, are found for the environments of the
sources studied here. It is shown that appreciable amounts of cosmic microwave
background diminution (the Sunyaev-Zel'dovich effect) are expected from many of
these clusters. This could be detected at high frequency where the emission
from the radio sources is weak.

</DOC>
<DOC>
<DOCNO> 120415 </DOCNO>
The tetra-lobed planetary nebula NGC 1501


  Direct imagery and long-slit, spatially resolved echellograms of the high
excitation planetary nebula NGC 1501 allowed us to study in detail the
expansion velocity field, the physical conditions (electron temperature,
electron density, ionization) and the spatial distribution of the nebular gas.
An electron temperature of 11500 K and a turbulence of 18 km/s are derived by
comparing the Halpha and [OIII] emission line profiles, but large, small scale
fluctuations of both these quantities are present in the ionized gas. The
radial density distribution shows external peaks up to 1400 cm-3; they have
steep outwards profiles and extended inwards tails probably originated by
Rayleigh-Taylor instability and winds interaction. The complexity of the
expanding motions indicates that the main part of NGC 1501 is a thin ellipsoid
of moderate ellipticity, but the presence of a pair of large lobes along both
the major and the intermediate axes and of a multitude of smaller bumps spread
on the whole nebular surface, makes the general 3-D structure of NGC 1501 like
a boiling, tetra-lobed shell. This peculiar morphology can be qualitatively
explained in terms of interaction of the slow nebular material with the intense
and fast wind from the WC4/OVI central star.

</DOC>
<DOC>
<DOCNO> 11912 </DOCNO>
Heterogeneities in Supercooled liquids: A Density Functional Study


  A metastable state, characterized by a low degree of mass localization is
identified using Density Functional Theory. This free energy minimum, located
through the proper evaluation of the competing terms in the free energy
functional, is independent of the specific form of the DFT used. Computer
simulation results on particle motion indicate that this heterogeneous state
corresponds to the supercooled state.

</DOC>
<DOC>
<DOCNO> 85026 </DOCNO>
Causal Implication and the Origin of Time Dilation


  We discuss the emergence of time dilation as a normal feature expected of any
system where a central processor may have to wait one or more clock cycles
before concluding a local calculation. We show how the process of causal
implication in a typical Newtonian cellular automaton leads naturally to
Lorentz transformations and invariant causal structure.

</DOC>
<DOC>
<DOCNO> 85191 </DOCNO>
On a General Class of Wormhole Geometries


  A general class of solutions is obtained which describe a spherically
symmetric wormhole system. The presence of arbitrary functions allows one to
describe infinitely many wormhole systems of this type. The source of the
stress-energy supporting the structure consists of an anisotropic brown dwarf
``star'' which smoothly joins the vacuum and may possess an arbitrary
cosmological constant. It is demonstrated how this set of solutions allows for
a non-zero energy density and therefore allows positive stellar mass as well as
how violations of energy conditions may be minimized. Unlike examples
considered thus far, emphasis here is placed on construction by manipulating
the matter field as opposed to the metric. This scheme is generally more
physical than the purely geometric method. Finally, explicit examples are
constructed including an example which demonstrates how multiple closed
universes may be connected by such wormholes. The number of connected universes
may be finite or infinite.

</DOC>
<DOC>
<DOCNO> 69851 </DOCNO>
New approach for calculating heavy-to-light form factors with QCD sum


  We suggest a new approach for calculating heavy-to-light form factors. The
method is based on light cone sum rules (LCSR) and covers the whole kinematical
range of momentum transfer. The derivation of the new sum rule uses a suitable
combination of double and single dispersion integrals. As an example we give
numerical results for the form factor f^+ for the B -> pion transition.

</DOC>
<DOC>
<DOCNO> 11578 </DOCNO>
Energy and symmetry of ordered 2D clusters in a parabolic confinement


  We report an experimental study of 2D dipole clusters formed by small
magnetic particles floating at the air-water interface. The particles form
hexagonally ordered clusters due to interplay between dipole-dipole repulsion
and confining external forces. Optical images of the clusters allow
determination of area S, total energy E, and the chemical potential for
different particle numbers N<130. Asymptotic expressions for E(N), S(N) account
fairly well for the smooth part of our experimental results. However, on top of
the smooth dependences we observe quasiperiodic fluctuations with dips at
``magic'' numbers corresponding to particularly symmetric cluster
configurations. The magnitude and occurrence of these fluctuations are related
to the symmetry of the cluster and to the center of mass position. This is in
full agreement with the recent prediction of Koulakov and Shklovskii for Wigner
crystal island.

</DOC>
<DOC>
<DOCNO> 70344 </DOCNO>
Improved Methods for Observing CP Violation in B+/- --> K+/- D0 and


  Various methods are discussed for obtaining the CKM angle gamma through the
interference of the charged B-meson decay channels B- -> K- D0 and B- -> K-
D0-bar where the D0 and D0-bar decay to common final states. It is found that
choosing final states which are not CP eigenstates can lead to large direct CP
violation which can give significant bounds on gamma without any theoretical
assumptions. If two or more modes are studied, gamma may be extracted with a
precision on the order of +/-15 degrees given about 10^8 B-mesons. We also
discuss the case of three body decays of the D0 where additional information
may be obtained from the distribution of the D0 decay products and consider the
impact of D-D-bar oscillations.

</DOC>
<DOC>
<DOCNO> 72249 </DOCNO>
Spontaneous CP Violation in the Next-to-Minimal Supersymmetric Standard


  We re-examine spontaneous CP violation at the tree level in the context of
the next-to-minimal supersymmetric standard model (NMSSM) with two Higgs
doublets and a gauge singlet field. We analyse the most general Higgs potential
without a discrete Z_3 symmetry, and derive an upper bound on the mass of the
lightest neutral Higgs boson consistent with present experimental data. We
investigate, in particular, its dependence on the admixture and CP-violating
phase of the gauge singlet field, as well as on tan(beta). To assess the
viability of the spontaneous CP violation scenario, we estimate epsilon_K by
applying the mass insertion approximation. We find that a non-trivial flavour
structure in the soft-breaking A terms is required to account for the observed
CP violation in the neutral kaon sector. Furthermore, combining the
minimisation conditions for spontaneous CP violation with the constraints
coming from K0-K0bar mixing, we find that the upper bound on the lightest
Higgs-boson mass becomes stronger. We also point out that the electric dipole
moments of electron and neutron are a serious challenge for SUSY models with
spontaneous CP violation.

</DOC>
<DOC>
<DOCNO> 150920 </DOCNO>
Probability Current and Trajectory Representation


  A unified form for real and complex wave functions is proposed for the
stationary case, and the quantum Hamilton-Jacobi equation is derived in the
three-dimensional space. The difficulties which appear in Bohm's theory like
the vanishing value of the conjugate momentum in the real wave function case
are surmounted. In one dimension, a new form of the general solution of the
quantum Hamilton-Jacobi equation leading straightforwardly to the general form
of the Schr\"odinger wave function is proposed. For unbound states, it is shown
that the invariance of the reduced action under a dilatation plus a rotation of
the wave function in the complex space implies that microstates do not appear.
For bound states, it is shown that some freedom subsists and gives rise to the
manifestation of microstates not detected by the Schr\"odinger wave function.

</DOC>
<DOC>
<DOCNO> 84489 </DOCNO>
Bianchi Type I Cosmologies in Arbitrary Dimensional Dilaton Gravities


  We study the low energy string effective action with an exponential type
dilaton potential and vanishing torsion in a Bianchi type I space-time
geometry. In the Einstein and string frames the general solution of the
gravitational field equations can be expressed in an exact parametric form.
Depending on the values of some parameters the obtained cosmological models can
be generically divided into three classes, leading to both singular and
nonsingular behaviors. The effect of the potential on the time evolution of the
mean anisotropy parameter is also considered in detail, and it is shown that a
Bianchi type I Universe isotropizes only in the presence of a dilaton field
potential or a central deficit charge.

</DOC>
<DOC>
<DOCNO> 178894 </DOCNO>
Unified optical-model approach to low-energy antiproton annihilation on


  A successful unified description of $\bar p$ nuclear interactions near E=0 is
achieved using a $\bar p$ optical potential within a folding model, $V_{{\rm
opt}} \sim \bar v * {\rho}$, where a $\bar p p$ potential $\bar v$ is folded
with the nuclear density $\rho$. The potential $\bar v$ fits very well the
measured $\bar p p$ annihilation cross sections at low energies ($p_L < 200$
MeV/c) and the $1s$ and $2p$ spin-averaged level shifts and widths for the
$\bar p$H atom. The density-folded optical potential $V_{{\rm opt}}$ reproduces
satisfactorily the strong-interaction level shifts and widths over the entire
periodic table, for $A > 10$, as well as the few low energy $\bar p$
annihilation cross sections measured on Ne. Both $\bar v$ and $V_{{\rm opt}}$
are found to be highly absorptive, which leads to a saturation of reaction
cross sections in hydrogen and on nuclei. Predictions are made for $\bar p$
annihilation cross sections over the entire periodic table at these very low
energies and the systematics of the calculated cross sections as function of
$A$, $Z$ and $E$ is discussed and explained in terms of a Coulomb-modified
strong-absorption model. Finally, optical potentials which fit simultaneously
low-energy $\bar p - ^4$He observables for $E < 0$ as well as for $E > 0$ are
used to assess the reliability of extracting Coulomb modified $\bar p$ nuclear
scattering lengths directly from the data. The relationship between different
kinds of scattering lengths is discussed and previously published systematics
of the $\bar p$ nuclear scattering lengths is updated.

</DOC>
<DOC>
<DOCNO> 10524 </DOCNO>
First-order transitions in fluctuating 1+1-dimensional nonequilibrium


  We demonstrate that first-order phase transitions in 1+1-dimensional
nonequilibrium systems with fluctuating ordered phases are impossible, provided
that there are no additional conservation laws, long-range interactions,
macroscopic currents, or special boundary conditions. Since minority islands in
the ordered phase of such systems can only shrink by short-range interactions,
it is impossible to stabilize a fluctuating ordered state. The apparent
first-order behavior turns out to be a transient phenomenon, crossing over to a
continuous transition after very long time. As examples we consider the triplet
creation model 3X->4X, X->O, the annihilation/fission process 2X->3X, 2X->O, as
well as spreading on a diffusing background X+Y->2Y, Y->X.

</DOC>
<DOC>
<DOCNO> 122031 </DOCNO>
Fitting BOOMERANG and MAXIMA-1 data with a Einstein-Yang-Mills


  We analyse the implications of recent Cosmic Microwave Background (CMB) data
for a specific cosmological model, based on the higher-dimensional
Einstein-Yang-Mills System compactified on a $R\times S^3\times S^d$ topology
and conclude that the model parameters are tightly constrained by CMB spectra.
Moreover, the model predicts a relationship between the deceleration parameter
at present, $q_0$, and some characteristic features of CMB spectra, namely the
height of the first peak and the location of the second peak, that is
consistent with the observations and which can be further tested by future CMB
and other experiments.

</DOC>
<DOC>
<DOCNO> 12750 </DOCNO>
Quantum phase transitions


  Phase transitions which occur at zero temperature when some non-thermal
parameter like pressure, chemical composition or magnetic field is changed are
called quantum phase transitions. They are caused by quantum fluctuations which
are a consequence of Heisenberg's uncertainty principle. These lecture notes
give a pedagogical introduction to quantum phase transitions. After collecting
a few basic facts about phase transitions and critical behavior we discuss the
importance of quantum mechanics and the relation between quantum and classical
transitions as well as their experimental relevance. As a primary example we
then consider the Ising model in a transverse field. We also briefly discuss
quantum phase transitions in itinerant electron systems and their connection to
non-Fermi liquid behavior.

</DOC>
<DOC>
<DOCNO> 84282 </DOCNO>
Gravity Quanta, Entropy and Black Holes


  We propose the use of a gravitational uncertainty principle for gravitation.
We define the corresponding gravitational Planck's constant and the
gravitational quantum of mass. We define entropy in terms of the quantum of
gravity with the property of having an extensive quality. The equivalent 2nd
law of thermodynamics is derived, the entropy increasing linearly with
cosmological time. These concepts are applied to the case of black holes,
finding their entropy and discussing their radiation.

</DOC>
<DOC>
<DOCNO> 83427 </DOCNO>
One Sense per Collocation and Genre/Topic Variations


  This paper revisits the one sense per collocation hypothesis using
fine-grained sense distinctions and two different corpora. We show that the
hypothesis is weaker for fine-grained sense distinctions (70% vs. 99% reported
earlier on 2-way ambiguities). We also show that one sense per collocation does
hold across corpora, but that collocations vary from one corpus to the other,
following genre and topic variations. This explains the low results when
performing word sense disambiguation across corpora. In fact, we demonstrate
that when two independent corpora share a related genre/topic, the word sense
disambiguation results would be better. Future work on word sense
disambiguation will have to take into account genre and topic as important
parameters on their models.

</DOC>
<DOC>
<DOCNO> 150386 </DOCNO>
Superconformal hypermultiplets in superspace


  We use the manifestly N=2 supersymmetric, off-shell, harmonic (or twistor)
superspace approach to solve the constraints implied by four-dimensional N=2
superconformal symmetry on the N=2 non-linear sigma-model target space, known
as the special hyper-K"ahler geometry. Our general solution is formulated in
terms of a homogeneous (of degree two) function of unconstrained (analytic)
Fayet-Sohnius hypermultiplet superfields. We also derive the improved (N=2
superconformal) actions for the off-shell (constrained) N=2 projective
hypermultiplets, and relate them (via non-conformal deformations) to the
asymptotically locally-flat (ALF) A_k and D_k series of the gravitational
instantons. The same metrics describe Kaluza-Klein monopoles in M-theory, while
they also arise in the quantum moduli spaces of N=4 supersymmetric gauge field
theories with SU(2) gauge group and matter hypermultiplets in three spacetime
dimensions. We comment on rotational isometries versus translational isometries
in the context of N=2 NLSM in terms of projective hypermultiplets.

</DOC>
<DOC>
<DOCNO> 11219 </DOCNO>
Bounded Fluctuations and Translation Symmetry Breaking in


  We present general results for one-dimensional systems of point charges
(signed point measures) on the line with a translation invariant distribution
$\mu$ for which the variance of the total charge in an interval is uniformly
bounded (instead of increasing with the interval length). When the charges are
restricted to multiples of a common unit, and their average charge density does
not vanish, then the boundedness of the variance implies translation-symmetry
breaking --- in the sense that there exists a function of the charge
configuration that is nontrivially periodic under translations --- and hence
that $\mu$ is not ``mixing.'' Analogous results are formulated also for one
dimensional lattice systems under some constraints on the values of the charges
at the lattice sites and their averages. The general results apply to
one-dimensional Coulomb systems, and to certain spin chains, putting on common
grounds different instances of symmetry breaking encountered there.

</DOC>
<DOC>
<DOCNO> 150859 </DOCNO>
The spectrum of BPS branes on a noncompact Calabi-Yau


  We begin the study of the spectrum of BPS branes and its variation on lines
of marginal stability on O_P^2(-3), a Calabi-Yau ALE space asymptotic to
C^3/Z_3. We show how to get the complete spectrum near the large volume limit
and near the orbifold point, and find a striking similarity between the
descriptions of holomorphic bundles and BPS branes in these two limits. We use
these results to develop a general picture of the spectrum. We also suggest a
generalization of some of the ideas to the quintic Calabi-Yau.

</DOC>
<DOC>
<DOCNO> 123321 </DOCNO>
Future High Energy Neutrino Telescopes


  This talk summarizes the main physics goals and basic methods of telescopes
for high energy neutrinos. It reviews the present status of deep underwater
telescopes and sketches the ICECUBE project as an example for a cube kilometer
detector. It is suggested to develop techniques for radio and acoustic
detection hand in hand with big optical arrays. These large arrays should be
complemented by medium-size detectors in the Megaton range.

</DOC>
<DOC>
<DOCNO> 123238 </DOCNO>
A 2MASS L Dwarf Companion to the Nearby K Dwarf GJ 1048


  We report the discovery of a probable L1 companion to the nearby K2 dwarf GJ
1048 using the Two Micron All-Sky Survey (2MASS). This source, 2MASSI
J0235599-233120 or GJ 1048B, has 2MASS near-infrared colors and absolute
magnitudes consistent with an early L dwarf companion with a projected
separation of 250 A.U. The L1 spectral type is confirmed by far-red optical and
low-resolution IR spectroscopy. We present evidence that GJ 1048 is a young
(<~1 Gyr) system, and that GJ 1048B may be a high-mass brown dwarf below the
hydrogen-burning limit. Additional studies of the GJ 1048 system will help
constrain the characteristics of L dwarfs as a function of age and mass.

</DOC>
<DOC>
<DOCNO> 100910 </DOCNO>
On Combined Standard-Nonstandard or Hybrid (q,h)-Deformations


  Combined $(q,h)$-deformations proposed by Kupershmidt and
Ballesteros-Herranz-Parashar are studied. In each case a transformation is
shown to lead to an equivalent, standard $q$-deformation. We briefly indicate
that appropriate singular limits of the same type of transformations can
however lead from standard biparametric $(p,q)$-deformations to non-hybrid but
biparametric nonstandard $(g,h)$ ones. Finally a case of hybrid
$(q,h)$-deformation is recalled, related to the superalgebra $GL(1|1)$.

</DOC>
<DOC>
<DOCNO> 84823 </DOCNO>
Does a Kalb-Ramond field make spacetime optically active


  A spacetime with torsion produced by a Kalb-Ramond field coupled
gravitationally to the Maxwell field, in accordance with a recent proposal by
two of us (PM and SS), is argued to lead to an optical activity in synchrotron
radiation from cosmologically distant radio sources. We suggest that this could
qualitatively explain observational data from a large number of radio sources
displaying such polarization asymmetry (after eliminating effects of Faraday
rotation due to magnetized galactic plasma). Possible implications for
heterotic string theory are also outlined.

</DOC>
<DOC>
<DOCNO> 122345 </DOCNO>
The Steady Spin Down Rate of 4U 1907+09


  Using X-ray data from the Rossi X-Ray Timing Explorer (RXTE), we report the
pulse timing results of the accretion powered high mass X-ray binary (HMXRB)
pulsar 4U 1907+09 covering a time span of almost two years. We measured three
new pulse periods in addition to the previously measured four pulse periods. We
are able to connect pulse arrival times in phase for more than a year. The
source has been spinning down almost at a constant rate with a spin down rate
of
 \dot \nu = (-3.54 \pm 0.02) \times 10^{-14} Hz s ^{-1} for more than
 15 years. Residuals of pulse arrival times yield a very low level of random
walk noise strengths
 \sim 2 \times 10^{-20} rad ^{2} sec ^{-3} on a time scale of 383 days, which
is four decades lower than that of the HMXRB pulsar Vela X-1. The noise
strength is only a factor of 5 greater than that of the low mass X-ray binary
pulsar (LMXRB) 4U 1626-67. The low level of the timing noise and the very
stable spin down rate of 4U 1907+09 makes this source unique among the HMXRBs,
providing another example, in addition to 4U 1626-67, of long term quiet spin
down from an accreting source. These examples show that the extended quiet spin
down episodes observed in the anomalous X-ray pulsars (AXPs) pulsars 1RXS
J170849.0-400910 and 1E 2259+586 do not necessarly imply that these sources are
not accreting pulsars.

</DOC>
<DOC>
<DOCNO> 118211 </DOCNO>
Jet directions in Seyfert galaxies: B and I imaging data


  We present the results of broad-band B and I imaging observations for a
sample of 88 Seyfert galaxies (29 Seyfert 1's and 59 Seyfert 2's), selected
from a mostly isotropic property, the flux at 60$\mu$m. We also present the B
and I imaging results for an additional sample of 20 Seyfert galaxies (7
Seyfert 1's and 13 Seyfert 2's), selected from the literature and known to have
extended radio emission. The I band images are fitted with ellipses to
determine the position angle and ellipticity of the host galaxy major axis.
This information will be used in a future paper, combined with information from
radio observations, to study the orientation of radio jets relative to the
plane of their host galaxies (Kinney et al. 2000). Here we present surface
brightness profiles and magnitudes in the B and I bands, as well as mean
ellipticities and major axis position angles.

</DOC>
<DOC>
<DOCNO> 70602 </DOCNO>
Estimation of Collision Impact Parameter


  We demonstrate that the nuclear collision geometry (i.e. impact parameter)
can be determined with 1.5 fm accuracy in an event-by-event analysis by
measuring the transverse energy flow in the pseudorapidity region $3 \le |\eta|
\le 5$ with a minimal dependence on collision dynamics details at the LHC
energy scale. Using the HIJING model we have illustrated our calculation by a
simulation of events of nucleus-nucleus interactions at the c.m.s energy from 1
up to 5.5 TeV per nucleon and various type of nuclei.

</DOC>
<DOC>
<DOCNO> 121021 </DOCNO>
Fragmentation of a Protostellar Core: The Case of CB230


  The Bok globule CB230 (L1177) contains an active, low-mass star-forming core
which is associated with a double NIR reflection nebula, a collimated bipolar
molecular outflow, and strong mm continuum emission. The morphology of the NIR
nebula suggests the presence of a deeply embedded, wide binary protostellar
system. High-angular resolution observations now reveal the presence of two
sub-cores, two distinct outflow centers, and an embedded accretion disk
associated with the western bipolar NIR nebula. In terms of separation and
specific angular momentum, the CB230 double protostar system probably results
from core fragmentation and can be placed at the upper end of the pre-main
sequence binary distribution.

</DOC>
<DOC>
<DOCNO> 119646 </DOCNO>
The Size-Frequency Distribution of the Zodiacal Cloud: Evidence from the


  Recent observations of the size-frequency distribution of zodiacal cloud
particles obtained from the cratering record on the LDEF satellite (Love and
Brownlee 1993) reveal a significant large particle population (100 micron
diameter or greater) near 1 AU. Our previous modeling of the Solar System dust
bands (Grogan et al 1997), features of the zodiacal cloud associated with the
comminution of Hirayama family asteroids, has been limited by the fact that
only small particles (25 micron diameter or smaller) have been considered. This
was due to the prohibitively large amount of computing power required to
numerically analyze the dynamics of larger particles. The recent availability
of cheap, fast processors has finally made this work possible. Models of the
dust bands are created, built from individual dust particle orbits, taking into
account a size-frequency distribution of the material and the dynamical history
of the constituent particles. These models are able to match both the shapes
and amplitudes of the dust band structures observed by IRAS in multiple
wavebands. The size-frequency index, q, that best matches the observations is
approximately 1.4, consistent with the LDEF results in that large particles are
shown to dominate. However, in order to successfully model the `ten degree'
band, which is usually associated with collisional activity within the Eos
family, we find that the mean proper inclination of the dust particle orbits
has to be approximately 9.35 degrees, significantly different to the mean
proper inclination of the Eos family (10.08 degrees).

</DOC>
<DOC>
<DOCNO> 11643 </DOCNO>
Solutions of Gross-Pitaevskii equations beyond the hydrodynamic


  We develop the multiscale technique to describe excitations of a
Bose-Einstein condensate (BEC) whose characteristic scales are comparable with
the healing length, thus going beyond the conventional hydrodynamical
approximation. As an application of the theory we derive approximate explicit
vortex and other solutions. The dynamical stability of the vortex is
discussed on the basis of the mathematical framework developed here, the result
being that its stability is granted at least up to times of the order of
seconds, which is the condensate lifetime. Our analytical results are confirmed
by the numerical simulations.

</DOC>
<DOC>
<DOCNO> 8620 </DOCNO>
Coupling to spin fluctuations from conductivity scattering rates


  A recent analysis of optical conductivity data which has provided strong
evidence for coupling of the charge carriers to the 41 meV spin resonance, seen
in the superconducting state of optimally doped Y123, is extended to other
systems. We find that the corresponding spin resonance is considerably broader
in Tl2201 and Y124 than it is in Bi2212. On the other hand, in overdoped Tl2201
with T_c = 23 K no resonance forms. A more specific interpretation of the
optical data in terms of a spin fluctuation exchange mechanism of
superconductivity gives an underlying effective spectral density which is
strongly temperature dependent and which contains important feedback effects
that further stabilize superconductivity as the temperature is reduced.

</DOC>
<DOC>
<DOCNO> 7752 </DOCNO>
Interpretation of a microwave induced current step in a single intrinsic


  Thin stacks consisting of a single intrinsic Josephson junction on
(Bi,Pb)-Sr-Ca-Cu-O thin films are investigated under the influence of external
microwave fields. The $I$-$V$-characteristic shows a single resistive branch, a
clear superconducting gap edge structure and a pronounced current step in
external microwave fields. With increasing irradiation power it shifts to
higher voltages, while the height of the step remains practically unchanged. In
a numerical simulation including an ac-magnetic field parallel to the
superconducting layers the experimental features of the structure can be
explained by a collective motion of Josephson fluxons.

</DOC>
<DOC>
<DOCNO> 68051 </DOCNO>
$B\to X_s\tau^+\tau^-$ in a CP spontaneously broken two Higgs doublet


  The differential branching ratio, CP asymmetry and lepton polarization $P_N$
for $B\to ^M X_s\tau^+\tau^-$ in a CP spotaneously broken two Higgs doublet
model are compute d. ^M It is shown that contributions of neutral Higgs bosons
to the decay are ^M quite significant when $\tan\beta$ is large and $P_N$ can
reach five persent.

</DOC>
<DOC>
<DOCNO> 69239 </DOCNO>
The Chiral Fermion Meson Model at Finite Temperature


  We study the chiral fermion meson model which is the well known linear sigma
model of Gell-Mann-and-Levy at finite temperature.A modified self-consistent
resummation (MSCR) which resums higher order terms in the perturbative
expansion is proposed. It is shown that with the MSCR the problem of tachyonic
masses is solved, the renormalization of the gap equations is carried out and
the Goldstone's theorem is verified. We also apply the method to investigate
another known case at high temperature and compare with results found in the
literature.

</DOC>
<DOC>
<DOCNO> 120681 </DOCNO>
The Subluminous Type Ia Supernova 1998de in NGC 252


  We present spectroscopic and extensive photometric observations of supernova
(SN) 1998de in the S0 galaxy NGC 252, discovered during the course of the Lick
Observatory Supernova Search. These data, which span a time period of 8 days
before to 76 days after $B$-band maximum, unambigously establish SN 1998de as a
peculiar and subluminous SN Ia with strong similarities to SN 1991bg, the
prototype of these intrinsically dim SNe Ia. We find that subluminous SNe Ia
with the same Delta m_{15}(B) can have slightly different light curves at
longer wavelengths. The notable spectroscopic similarities between SN 1998de
and SN 1991bg are the wide Ti II trough at 4100-4500 A, the strong Ca II
features, and the early onset of the nebular phase. We observe that
spectroscopic deviations of SN 1998de from SN 1991bg increase toward redder
wavelenghts. These deviations include the absence of the conspicuous Na I D
absorption found in SN 1991 at 5700 A, and the evolution of a region (6800-7600
A) from featureless to feature-rich. Several lines of evidence suggest that SN
1998de was a slightly more powerful explosion than SN 1991bg. We discuss the
implications of our observations for progenitor models and the explosion
mechanism of peculiar, subluminous SNe Ia. The extensive photometric data make
SN 1998de a better template than SN 1991bg for calibrating the low-luminosity
end of the luminosity vs. decline-rate relationship.

</DOC>
<DOC>
<DOCNO> 13505 </DOCNO>
Bicritical and tetracritical phenomena and scaling properties of the


  By large scale Monte Carlo simulations it is shown that the stable fixed
point of the SO(5) theory is either bicritical or tetracritical depending on
the effective interaction between the antiferromagnetism and superconductivity
orders. There are no fluctuation-induced first-order transitions suggested by
epsilon expansions. Bicritical and tetracritical scaling functions are derived
for the first time and critical exponents are evaluated with high accuracy.
Suggestions on experiments are given.

</DOC>
<DOC>
<DOCNO> 101535 </DOCNO>
Quasiclassical Calculations in Beam Dynamics


  We present some applications of general harmonic/wavelet analysis approach
(generalized coherent states, wavelet packets) to numerical/analytical
calculations in (nonlinear) quasiclassical/quantum beam dynamics problems.
(Naive) deformation quantization, multiresolution representations and Wigner
transform are the key points.

</DOC>
<DOC>
<DOCNO> 9811 </DOCNO>
Rapidly Rotating Fermi Gases


  We show that the density profile of a Fermi gas in rapidly rotating potential
will develop prominent features reflecting the underlying Landau level like
energy spectrum. Depending on the aspect ratio of the trap, these features can
be a sequence of ellipsoidal volumes or a sequence of quantized steps.

</DOC>
<DOC>
<DOCNO> 83238 </DOCNO>
Verifying Termination and Error-Freedom of Logic Programs with block


  We present verification methods for logic programs with delay declarations.
The verified properties are termination and freedom from errors related to
built-ins. Concerning termination, we present two approaches. The first
approach tries to eliminate the well-known problem of speculative output
bindings. The second approach is based on identifying the predicates for which
the textual position of an atom using this predicate is irrelevant with respect
to termination. Three features are distinctive of this work: it allows for
predicates to be used in several modes; it shows that block declarations, which
are a very simple delay construct, are sufficient to ensure the desired
properties; it takes the selection rule into account, assuming it to be as in
most Prolog implementations. The methods can be used to verify existing
programs and assist in writing new programs.

</DOC>
<DOC>
<DOCNO> 71771 </DOCNO>
Supersymmetric Triplet Higgs Model of Neutrino Masses and Leptogenesis


  We construct a supersymmetric version of the triplet Higgs model for neutrino
masses, which can generate a baryon asymmetry of the Universe through
lepton-number violation and is consistent with the gravitino constraints.

</DOC>
<DOC>
<DOCNO> 116836 </DOCNO>
Energy stabilization of 1.5 GeV S-Band linac


  KEK-ATF is studying low emittance, multi-bunch electron beam for the future
linear collider. The energy instability of the 1.5 GeV linac has been a problem
making the beam injection to the damping ring unstable. Because the unstable
beam generates also large amount of the radiation, the beam current is limited
by the KEK radiation safety policy much lower than what we expect. Stabilizing
the S-band linac is therefore important not only to improve the beam quality,
but also to clear the radiation safety limit to start the multi-bunch
operation.
  We have made various modifications to solve the problem on the electron gun,
modulator, klystron etc. For the modulator, we have developed a feed-forward
controlled De-Q module. This module compensates the voltage jitter by
controlling the deQ timing with a feed-forward circuit because the amount of
the excessive charge up is strongly correlated to the charge up slope that can
be measured prior to the deQ timing. The energy stability was examined and was
improved by a factor of 3, from 0.6% to 0.2% of itself. Modification for the
feed-forward circuit to get more stability was made. The test for the new
circuit is in progress. For the long term instability, phase-lock system for
klystron RF is being installed. In the test operation, it showed a good
performance and compensate the phase drift less than 1 deg.

</DOC>
<DOC>
<DOCNO> 13124 </DOCNO>
Microwave induced resonant backscattering in a one-dimensional


  We have studied a one-dimensional channel with a wider, straight region
irradiated by an external electromagnetic field. In this system the interplay
between interference effects and resonance phenomena manifests itself and
provides a new behavior of conduction. We show that the transport properties of
the system can be affected by changing frequency and the amplitude of the
external field. We also show that for certain combinations of these parameters
electron transport through the system is complitely blocked.

</DOC>
<DOC>
<DOCNO> 12123 </DOCNO>
Incommensurate Spin-Peierls Phases in the One-Dimensional Quantum


  Using the numerical approach for a study of the thermodynamic properties of
the nonuniform one-dimensional spin-1/2 isotropic XY model in a transverse
field we examine different lattice distortions to reveal which spin-Peierls
phases are realized in the magnetic chain at zero temperature in the presence
of external field.

</DOC>
<DOC>
<DOCNO> 71546 </DOCNO>
Determining the Equation of State of the Expanding Universe Using a New


  To determine the equation of state of the universe, we propose to use a new
independent variable $R\equiv (H_0/c)(d_L(z)/(1+z))$, where $H_0$ and $d_L(z)$
are the present Hubble parameter and the luminosity distance, respectively. For
the flat universe suggested from the observation of the anisotropy of cosmic
microwave background, the density and the pressure are expressed as
$\rho/\rho_0=4(df/dR)^2/f^6$ and $p/\rho_0=-4/3(d^2f/dR^2)/f^5$ where $\rho_0$
is the present density and $f(R)=1/\sqrt{1+z(R)}$. In $(R, f)$ plane the sign
as well as the strength of the pressure is in proportion to the curvature of
the curve $f(R)$. We propose to adopt a Pade-like expression of
$f(R)=1/\sqrt{u}$ with $u\equiv 1+\sum\limits_{n=1}^{N}u_nR^n$. For flat
$\Lambda$ model the expansion up to N=7 has at most an error $< 0.2%$ for $z <
1.7$ and any value of $\Lambda$. We also propose a general method to determine
the equation of state of the universe which has $N-1$ free parameters. If the
number of parameters are smaller than $N-1$, there is a consistency check of
the equation of state so that we may confirm or refute each model.

</DOC>
<DOC>
<DOCNO> 39828 </DOCNO>
Results from the Palo Verde Neutrino Oscillation Experiment


  The $\nuebar$ flux and spectrum have been measured at a distance of about 800
m from the reactors of the Palo Verde Nuclear Generating Station using a
segmented Gd-loaded liquid scintillator detector. Correlated positron-neutron
events from the reaction $\nuebar$p$\to$e^+n were recorded for a period of 200
d including 55 d with one of the three reactors off for refueling. Backgrounds
were accounted for by making use of the reactor-on and reactor-off cycles, and
also with a novel technique based on the difference between signal and
background under reversal of the e^+ and n portions of the events. A detailed
description of the detector calibration, background subtraction, and data
analysis is presented here. Results from the experiment show no evidence for
neutrino oscillations. $\nuebar\to\bar\nu_x$ oscillations were excluded at 90%
CL for $\dm>1.12\times10^{-3}$ eV^2 for full mixing, and $\sinq>0.21$ for large
$\dm$. These results support the conclusion that the observed atmospheric
neutrino oscillations does not involve $\nu_{\rm e}$.

</DOC>
<DOC>
<DOCNO> 13809 </DOCNO>
The effects of spin fluctuations on the tunneling spectroscopy in


  We investigate the effects of spin fluctuations on the tunneling spectra of
the NS junction. In the high junction resistance limit, the dip/hump structure
observed in ARPES data for the high Tc superconductors is reproduced in a RPA
treatment of the t-t'-J model. It is shown that the dip/hump structure weakens
as doping increases as reflected in the data. In the other limit, we predict
that the zero bias Andreev peak can coexist with the dip/hump structure.
Furthermore, the c-axis tunneling spectra is found to be very similar to a
recent STM data once these fluctuations are included.

</DOC>
<DOC>
<DOCNO> 100894 </DOCNO>
On Embedding Circle-Bundles in Four-Manifolds


  We demonstrate an obstruction to finding certain splittings of four-manifolds
along sufficiently twisted circle bundles over Riemann surfaces, arising from
Seiberg-Witten theory. These obstructions are used to show a non-splitting
result for algebraic surfaces of general type.

</DOC>
<DOC>
<DOCNO> 40023 </DOCNO>
Hadronic Invariant Mass Spectrum in B -> X_u l nu Decay with Lepton


  We discuss the implications of charged lepton energy cut to the hadronic
invariant mass spectrum in charmless semileptonic B decays. Charged-lepton
energy cut is inevitable in order to remove secondary leptonic events such as b
-> c, tau -> l, and to identify the chaged leptons at detectors experimentally.
We consider three possible lepton energy cuts, E_l^{cuts} = 0.6,1.5,2.3 GeV,
and found that with the most probable cuts E_l^{cut} = 1.5 GeV and M_X^{max} =
1.5~(1.86) GeV, 45 ~ 60 % ~(58 ~ 67 %) of decay events survive. Therefore, B ->
X_u l nu decay events can be efficiently distinguished from B -> X_c l nu decay
events. We also discuss the possible model dependence on the results.

</DOC>
<DOC>
<DOCNO> 12876 </DOCNO>
Quantum Chern-Simons Vortices on a Sphere


  The quantisation of the reduced first-order dynamics of the nonrelativistic
model for Chern-Simons vortices introduced by Manton is studied on a sphere of
given radius. We perform geometric quantisation on the moduli space of static
solutions, using a Kaehler polarisation, to construct the quantum Hilbert
space. Its dimension is related to the volume of the moduli space in the usual
classical limit. The angular momenta associated with the rotational SO(3)
symmetry of the model are determined for both the classical and the quantum
systems. The results obtained are consistent with the interpretation of the
solitons in the model as interacting bosonic particles.

</DOC>
<DOC>
<DOCNO> 100174 </DOCNO>
Local complex Olshanskii semigroups are Stein


  This paper deals with the analytic continuation of holomorphic automorphic
forms. In particular we prove that for any discrete subgroup $\Gamma$ of a
hermitian Lie group $G$ there always exists a non-trivial holomorphic
automorphic form, i.e., there always exist a $\Gamma$-spherical unitary highest
weight representations. As an application we prove that local complex
Olshamskii semigroups $S/\Gamma\subseteq G_C/ \Gamma$ are Stein manifolds in
the case where $\Gamma$ is a uniform lattice. This is a little bit surprising
since the surrounding complex manifold $G_C/\Gamma$ is not Stein.

</DOC>
<DOC>
<DOCNO> 118549 </DOCNO>
The first radius-expansion X-ray burst from GX 3+1


  During several observations in 1999 August with RXTE of the low-mass X-ray
binary GX 3+1, we found a single short and strong X-ray burst. This is the
first burst from GX 3+1 which clearly shows evidence for radius expansion of
the neutron-star photosphere during the thermo-nuclear runaway. We show that
the cooling phase of the neutron star photosphere starts already just before
the end of the contraction phase. Considering the fact that the radius
expansion is due to the burst luminosity being at the Eddington luminosity,
assuming standard burst parameters and accounting for gravitational redshift
effects we derive a distance to the source of ~4.5 kpc, although relaxing these
assumptions may lead to uncertainties up to ~30%. By comparing the persistent
flux with that observed at the peak of the burst we infer that near the time of
the X-ray burst the persistent luminosity of GX 3+1 is ~0.17*L_edd, confirming
predictions from theoretical modeling of X-ray spectra of bright sources like
GX 3+1.

</DOC>
<DOC>
<DOCNO> 120769 </DOCNO>
Mid-infrared studies of the AGB star populations in the Local Group


  We present a brief summary of the ISO survey of AGB stars in 8 populous
intermediate age clusters of the Magellanic Clouds. Totally, more than 100 AGB
and RGB stars were observed at 4.5, 6.7 and 12 $\mu$m. We introduce a new
method to estimate effective temperatures of oxygen-rich AGB stars, and derive
precise bolometric magnitudes and effective temperatures for a large population
of AGB objects in both LMC and SMC. The derived stellar parameters are used to
construct observed HR diagrams which are employed further to estimate cluster
ages using the isochrone fitting. We show that proposed method gives a powerful
tool to study AGB star populations within the Local Group galaxies, especially,
when backed up with the observations from forthcoming mid-IR astronomical space
facilities (IRIS, SIRTF) and large ground-based telescopes (SUBARU, VLT, etc.).

</DOC>
<DOC>
<DOCNO> 151022 </DOCNO>
QED in external field with space-time uniform invariants. Exact


  We study exact solutions of Dirac and Klein-Gordon equations and Green
functions in d-dimensional QED and in an external electromagnetic field with
constant and homogeneous field invariants. The cases of even and odd dimensions
are considered separately, they are essentially different. We direct attention
to the asymmetry of the quasienergy spectrum, which appears in odd dimensions.
The in and out classification of the exact solutions as well as the
completeness and orthogonality relations is strictly proven. Different Green
functions in the form of sums over the exact solutions are constructed. The
Fock-Schwinger proper time integral representations of these Green functions
are found. As physical applications we consider the calculations of different
quantum effects related to the vacuum instability in the external field. For
example, we present mean values of particles created from the vacuum, the
probability of the vacuum remaining a vacuum, the effective action, and the
expectation values of the current and energy-momentum tensor.

</DOC>
<DOC>
<DOCNO> 121435 </DOCNO>
Do Cluster Cooling Flows Survive Head-on Galaxy Cluster Mergers?


  We report the results of recent numerical simulations of the head-on merger
of a cooling flow cluster with an infalling subcluster of galaxies. These
simulations examined the effects of different types of cluster mergers (with
16:1 and 4:1 mass ratios) on the evolution of cluster cooling flows (mass
accretion rates of 100 and 400 M/year. The 2-dimensional simulations were
performed with a Hydro/N-body code on a uniform grid with a resolution of 20
kpc.
  We find that the ram-pressure of the infalling gas is crucial in determining
the fate of the cooling flow as disruption occurs when a substantial amount of
subcluster gas reaches the primary's core. In such cases, the subcluster gas
can increase the central cooling time by displacing the high-density cooling
gas and by heating it via shocks and turbulent gas motions. Moreover, the fate
of a merging cooling flow is also dependent on its initial cooling time. In
cases where the initial cooling time is very small then, even if the flow is
disrupted, the central cooling time will remain less than a Hubble time and the
flow will likely re-establish itself. This has an important observational
consequence because such clusters will be classified as cooling flows even
though they have experienced a significant merger. In addition, there is a time
delay (1-2 Gyrs) between core-crossing and the point at which the central
cooling time of a disrupted flow becomes of order a Hubble time (abridged).

</DOC>
<DOC>
<DOCNO> 68431 </DOCNO>
Photoproduction constraints on J/psi-nucleon interactions


  Using J/psi and open charm photoproduction data, we apply the vector meson
dominance model to obtain constraints on the energy dependence of the inelastic
J/psi-nucleon cross section. Predictions of short distance QCD are in accord
with these constraints, while recently proposed hadronic models for J/psi
dissociation strongly violate them.

</DOC>
<DOC>
<DOCNO> 12533 </DOCNO>
Simulations of the 3d Ginzburg-Landau Model with Soft Amplitudes


  Using cluster Monte Carlo simulations, the 3d complex Ginzburg-Landau model
reveals a first order transition when the amplitude of the complex field is
sufficiently soft, i.e. adapts itself to the phase configurations of the field.
This transition is driven by phase fluctuations in agreement with a previous
analytical approach.

</DOC>
<DOC>
<DOCNO> 85033 </DOCNO>
A quasilocal Hamiltonian for gravity with classical and quantum


  I modify the quasilocal energy formalism of Brown and York into a purely
Hamiltonian form. As part of the reformulation, I remove their restriction that
the time evolution of the boundary of the spacetime be orthogonal to the leaves
of the time foliation. Thus the new formulation allows an arbitrary evolution
of the boundary which physically corresponds to allowing general motions of the
set of observers making up that boundary. I calculate the rate of change of the
quasilocal energy in such situations, show how it transforms with respect to
boosts of the boundaries, and use the Lanczos-Israel thin shell formalism to
reformulate it from an operational point of view. These steps are performed
both for pure gravity and gravity with attendant matter fields. I then apply
the formalism to characterize naked black holes and study their properties,
investigate gravitational tidal heating, and combine it with the path integral
formulation of quantum gravity to analyze the creation of pairs of charged and
rotating black holes. I show that one must use complex instantons to study this
process though the probabilities of creation remain real and consistent with
the view that the entropy of a black hole is the logarithm of the number of its
quantum states.

</DOC>
<DOC>
<DOCNO> 151198 </DOCNO>
Pauli Terms Must Be Absent In Dirac Equation


  It should be of interest, whether Dirac's equation involves all 16 basis
elements of his Clifford algebra $Cl_D.$ These include the 6 `tensorial'
$\sigma^{\mu\nu}$ with which the `Pauli terms' are formed. We find that these
violate a basic axiom of any *-algebra, when Dirac's $\Psi$ is canonical. Then
the Dirac operator is spanned only by the 10 elements
$1,i\gamma_5,\gamma^\mu,\gamma^\mu\gamma_5$ (which don't form a basis of $Cl_D$
because the $\sigma^{\mu\nu}$ are excluded).

</DOC>
<DOC>
<DOCNO> 100628 </DOCNO>
Algebraization of Frobenius splitting via quantum groups


  An important breakthrough in understanding the geometry of Schubert varieties
was the introduction of the notion of Frobenius split varieties and the result
that the flag varieties $G/P$ are Frobenius split. The aim of this article is
to give in this case a complete and self contained representation theoretic
approach to this method. The geometric Frobenius method (in char. $k=p>0$) will
here be replaced by Lusztig's Frobenius maps for quantum groups at roots of
unity (which exist not only for primes but any integer $\ell > 1$).

</DOC>
<DOC>
<DOCNO> 119120 </DOCNO>
The Near Infrared and Multiwavelength Afterglow of GRB 000301c


  We present near-infrared observations of the counterpart of GRB 000301c. The
K' filter (2.1 micron) light curve shows a well-sampled break in the decay
slope at t=3.5 days post-burst. The early time slope is very shallow (~ -0.1),
while the late time slope is steep (-2.2). Comparison with the optical (R band)
light curve shows marginally significant differences, especially in the early
time decay slope (which is steeper in the optical) and the break time (which
occurs later in the optical). This is contrary to the general expectation that
light curve breaks should either be achromatic (e.g., for breaks due to
collimation effects) or should occur later at longer wavelengths (for most
other breaks). The observed color variations might be intrinsic to the
afterglow, or might indicate systematic errors of > 0.08 magnitude in all
fluxes. Even if the break is achromatic, we argue that its sharpness poses
difficulties for explanations that depend on collimated ejecta. The R light
curve shows further signs of fairly rapid variability (a bump, steep drop, and
plateau) that are not apparent in the K' light curve. In addition, by combining
the IR-optical-UV data with millimeter and radio fluxes, we are able to
constrain the locations of the self-absorption break and cooling break and to
infer the location of the spectral peak at t=3 days: f_nu = 3.4 mJy at nu=1e12
Hz. Using the multiwavelength spectral energy distribution, we are able to
constrain the blast wave energy, which was E > 3e53 erg if the explosion was
isotropic. This implies a maximum gamma ray production efficiency of ~ 0.15 for
GRB 000301C.

</DOC>
<DOC>
<DOCNO> 151681 </DOCNO>
On the Dimensional Reduction Procedure


  The issue related to the so-called dimensional reduction procedure is
revisited within the Euclidean formalism. First, it is shown that for symmetric
spaces, the local exact heat-kernel density is equal to the reduced one, once
the harmonic sum has been succesfully performed. In the general case, due to
the impossibility to deal with exact results, the short time heat-kernel
asymptotics is considered. It is found that the exact heat-kernel and the
dimensionally reduced one coincide up to two non trivial leading contributions
in the short time expansion. Implications of these results with regard to
dimensional-reduction anomaly are discussed.

</DOC>
<DOC>
<DOCNO> 9330 </DOCNO>
Bosonization Rules for Electron-Hole Systems - II


  Here we write down and prove closed commutation rules for Fermi bilinears in
a two-component Fermi system in terms of the relevant sea-bosons. We show how
the commutation rules come out correctly within the RPA-approximation as do the
zero temperature correlation functions. We write down hamiltonains of
nonrelativistic interacting electron-hole systems and point out several
attractive features such as the natural roles excitons play in this language.
We then use this language to derive a set of equations analogous to the
Semiconductor Bloch Equations in the presence of phonons and with external
fields such as those present in pump-probe experiments. We solve these
equations using parameters of interesting and topical materials such as GaN and
compare with some recent experimental data.

</DOC>
<DOC>
<DOCNO> 150604 </DOCNO>
Four-point Functions of Lowest Weight CPOs in N=4 SYM_4 in Supergravity


  We show that the recently found quartic action for the scalars from the
massless graviton multiplet of type IIB supergravity compactified on
AdS_5\times S^5 background coincides with the relevant part of the action of
the gauged N=8 5d supergravity on AdS_5. We then use this action to compute the
4-point function of the lowest weight chiral primary operators
$\tr(\phi^{(i}\phi^{j)})$ in N=4 SYM_4 at large $N$ and at strong `t Hooft
coupling.

</DOC>
<DOC>
<DOCNO> 99969 </DOCNO>
The Tamagawa number conjecture for CM elliptic curves


  In this paper we prove the Tamagawa number conjecture of Bloch and Kato for
CM elliptic curves using a new explicit description of the specialization of
the elliptic polylogarithm. The Tamagawa number conjecture describes the
special values of the L-function of a CM elliptic curve in terms of the
regulator maps of the K-theory of the variety into Deligne and etale
cohomology. The regulator map to Deligne cohomology was computed by Deninger
with the help of the Eisenstein symbol. For the Tamagawa number conjecture one
needs an understanding of the $p$-adic regulator on the subspace of K-theory
defined by the Eisenstein symbol. This is accomplished by giving a new explicit
computation of the specialization of the elliptic polylogarithm sheaf. It turns
out that this sheaf is an inverse limit of $p^r$-torsion points of a certain
one-motive. The cohomology classes of the elliptic polylogarithm sheaf can then
be described by classes of sections of certain line bundles. These sections are
elliptic units and going carefully through the construction one finds an analog
of the elliptic Soul\'e elements. Finally Rubin's ``main conjecture'' of
Iwasawa theory is used to compare these elements with etale cohomology.

</DOC>
<DOC>
<DOCNO> 99486 </DOCNO>
Problems on geometric structures of projective embeddings


  This is a survey of our research on geometric structures of projective
embeddings and includes some topics of our talks in several symposia during
1990-99. We clarify our main problem, which is to construct a kind of geometric
composition series of projective embeddings. The concept of "geometric
composition series" is an analogy in Algebraic Geometry with Jordan-H\"{o}lder
series in Group Theory. We present two of the candidates for the construction
problem. To approach this problem, we show several results and new tools for
handling higher obstructions appearing in infinitesimal liftings. As a
byproduct of the tools, we obtain a simplified proof for a criterion on
arithmetic normality described in terms of Differential Geometry. (Keywords):
Petri's analysis, Second fundamental form, Syzygy, Arithmetic normality,
Infinitesimal lifting, Geometric shell, Geometric composition series, Lefschetz
chain, Dual Lefschetz chain, Meta-Lefschetz operator.

</DOC>
<DOC>
<DOCNO> 117129 </DOCNO>
Pulsed Superconductivity Acceleration


  The design of the proposed linear collider TESLA is based on 9-cell 1.3 GHz
superconducting niobium cavities, operated in pulsed mode. Within the framework
of an international collaboration the TESLA Test Facility (TTF) has been set up
at DESY, providing the infrastructure for cavity R&D towards higher gradients.
More than 60 nine-cell cavities were tested, accelerating gradients as high as
30 MV/m were measured. In the second production of TTF-cavities the average
gradient was measured to be 24.7 MV/m. Two modules, each containing eight
resonators, are presently used in the TTF-linac. These cavities are operated in
pulsed mode: 0.8 ms constant gradient with up to 10 Hz repetitions rate. We
will focus on two aspects: Firstly, the cavity fabrication and treatment is
discussed, allowing to reach high gradients. Latest results of single cell
cavities will be shown, going beyond 40 MV/m. Secondly, the pulsed mode
operation of superconducting cavities is reviewed. This includes Lorentz force
detuning, mechanical vibrations (microphonics) and rf field control. Both
topics meet the upcoming interest in superconducting proton linacs, like the sc
driver linac for SNS (Spallation Neutron Source).

</DOC>
<DOC>
<DOCNO> 118526 </DOCNO>
Photometry of Nova V 1493 Aql


  We report on photometric observations of V 1493 Aql during the early decline
and highlight some uncommon aspects of the light curve. V 1493 Aql was hotter
at maximum light than in the following phases, and was characterized by the
presence of a long lasting secondary maximum, that, unlike in other novae, was
quite red in color. The mean of three distance estimates yields d ~ 18.8 +/-
3.6 Kpc. Such a large distance would place V 1493 Aql at the extreme outskirts
of our Galaxy or even in an external Local Group galaxy.

</DOC>
<DOC>
<DOCNO> 119533 </DOCNO>
Modelling of the X-ray broad absorption features in Narrow-Line Seyfert


  We investigate the origin of the broad absorption features detected near
1-1.4 keV in several Narrow Line Seyfert 1 galaxies, by modelling the absorbing
medium with various physical parameters, using the ionization code PEGAS. The
observed properties of the X-ray absorption features can be reproduced by
taking into account the peculiar soft X-ray excess which is well fitted by a
blackbody plus an underlying power law. We equally stress that the emission
coming from the absorbing medium (related to the covering factor) has a strong
influence on the resulting X-ray spectrum, in particular on the apparent
position and depth of the absorption features. A non-solar iron abundance may
be required to explain the observed deep absorption. We also investigate the
influence of an additional collisional ionization process (hybrid case) on the
predicted absorption features.

</DOC>
<DOC>
<DOCNO> 101266 </DOCNO>
Special Lagrangian m-folds in C^m with symmetries


  This is the first in a series of papers on special Lagrangian submanifolds in
C^m. We study special Lagrangian submanifolds in C^m with large symmetry
groups, and give a number of explicit constructions. Our main results concern
special Lagrangian cones in C^m invariant under a subgroup G in SU(m)
isomorphic to U(1)^{m-2}. By writing the special Lagrangian equation as an
o.d.e. in G-orbits and solving the o.d.e., we find a large family of distinct,
G-invariant special Lagrangian cones on T^{m-1} in C^m.
  These examples are interesting as local models for singularities of special
Lagrangian submanifolds of Calabi-Yau manifolds. Such models will be needed to
understand Mirror Symmetry and the SYZ conjecture.

</DOC>
<DOC>
<DOCNO> 121944 </DOCNO>
High-resolution X-ray spectroscopy of the Seyfert 2 galaxy Circinus with


  Results from a 60 ks Chandra HETGS observation of the nearby Seyfert 2
Circinus are presented. The spectrum shows a wealth of emission lines at both
soft and hard X-rays, including lines of Ne, Mg, Si, S, Ar, Ca, and Fe, and a
prominent Fe Kalpha line at 6.4 keV. We identify several of the He-like
components and measure several of the Lyman lines of the H-like ions. The
lines' profiles are unresolved at the limited signal-to-noise ratio of the
data. Our analysis of the zeroth-order image in a companion paper constrains
the size of the emission region to be 20-60 pc, suggesting that emission within
this volume is almost entirely due to the reprocessing of the obscured central
source. Here we show that a model containing two distinct components can
reproduce almost all the observed properties of this gas. The ionized component
can explain the observed intensities of the ionized species, assuming
twice-solar composition and an N \propto r^{-1.5} density distribution. The
neutral component is highly concentrated, well within the 0.8arcsec point
source, and is responsible for almost all of the observed Kalpha (6.4 keV)
emission. Circinus seems to be different than Mkn~3 in terms of its gas
distribution.

</DOC>
<DOC>
<DOCNO> 40467 </DOCNO>
Exclusive hadronic Tau decays in the resonance effective action of QCD


  Until present the study of the form factors associated to the vector and
axial-vector components of the hadronic weak current has been carried out with
a plethora of modelizations of the underlying strong interactions. While of
importance to get an understanding of the dynamics involved, the amount and
quality of the experimental data start to show some discrepancies with the
analysed models. Moreover, and from a theoretical point of view, most of these
models are not consistent with quantum chromodynamics (QCD). We propose a
QCD-based model-independent procedure to analyse those decays through the use
of the resonance chiral theory, the low-energy effective action of QCD in the
relevant resonance region. Within this framework we study the hadronic
off-shell width of the Rho meson and the vector form factor of the pion in
Tau(-) -> Pi(-) Pi(0) nu_tau. We also comment on the Tau(-) -> (Pi Pi Pi)(-)
nu_tau decay.

</DOC>
<DOC>
<DOCNO> 13078 </DOCNO>
Quantized phonon specrum of single-wall carbon nanotubes


  The electronic spectra of carbon nanotubes and other nanoscale systems are
quantized because of their small radii. Similar quantization in the phonon
spectra has been difficult to observe because of the far smaller energy scale.
We probed this regime by measuring the temperature-dependent specific heat of
purified single-wall nanotubes. Thee data show direct evidence of
one-dimensional quanitized phonon subbands. Above 4 K, they are in excellent
agreement with model calculations of individual nanotubes and differ markedly
from the specific heat of two-dimensional graphene or three-dimensional
graphite. Detailed modeling yields an energy of 4.3 meV for the lowest
quantized phonon subband and a tube-tube (or "lattice") Debye energy of 1.1
meV, implying a small intertube coupling in bundles.

</DOC>
<DOC>
<DOCNO> 8367 </DOCNO>
Dynamics of two-particle granular collisions on a surface


  We experimentally examine the dynamics of two-particle collisions occuring on
a surface. We find that in two-particle collisions a standard coefficient of
restitution model may not capture crucial dynamics of this system. Instead, for
a typical collision, the particles involved slide relative to the substrate for
a substantial time following the collision; during this time they experience
very high frictional forces. The frictional forces lead to energy losses that
are larger than the losses due to particle inelasticity. In addition, momentum
can be transfered to the substrate, so that the momentum of the two particles
is not necessarily conserved. Finally, we measure the angular momenta of
particles immediately following the collision, and find that angular momentum
can be lost to the substrate following the collision as well.

</DOC>
<DOC>
<DOCNO> 70982 </DOCNO>
Hyperon-Nucleon Final State Interaction in Kaon Photoproduction of the


  Final state hyperon-nucleon interaction in strangeness photoproduction of the
deuteron is investigated making use of the covariant reaction formalism and the
P-matrix approach to the YN system. Remarkably simple analytical expression
for the amplitude is obtained. Pronounced effects due to final state
interaction are predicted including the manifestation of the 2.13 GeV
resonance.

</DOC>
<DOC>
<DOCNO> 174434 </DOCNO>
Projectile $\Delta$ and target-Roper excitation in the p (d, d')X


  In this paper we compare a model that contains the mechanisms of $\Delta$
excitation in the projectile and Roper excitation in the target with
experimental data from two (d, d') experiments on a proton target. The
agreement of the theory with the experiment is fair for the data taken at T_d =
2.3 GeV. The $\Delta$ excitation in the projectile is predicted close to the
observed energy with the correct width. The theory, however, underpredicts by
about 40% the cross sections measured at T_d = 1.6 GeV at angles where the
cross section has fallen by about two orders of magnitude. The analysis done
here allows to extract an approximate strength for the excitation of the Roper
[N^*(1440)] excitation and a qualitative agreement with the theoretical
predictions is also found.

</DOC>
<DOC>
<DOCNO> 13635 </DOCNO>
Is the quantum dot at large bias a weak-coupling problem?


  We examine the two-lead Kondo model for a d.c. biased quantum dot in the
Coulomb blockade regime. From perturbative calculations of the magnetic
susceptibility, we show that the problem retains its strong-coupling nature,
even at bias voltages larger than the equilibrium Kondo temperature. We give a
speculative discussion of the nature of the renormalization group flows and the
strong-coupling state that emerges at large voltage bias.

</DOC>
<DOC>
<DOCNO> 68529 </DOCNO>
Quantum Field Theory Solution to The Gauge Hierarchy And Cosmological


  A quantum field theory formalism is reviewed that leads to a self-consistent,
finite quantum gravity, Yang-Mills and Higgs theory, which is unitary and gauge
invariant to all orders of perturbation theory. The gauge hierarchy problem is
solved due to the exponential damping of the Higgs self-energy loop graph for
energies greater than a scale $\Lambda_H\leq 1$ TeV. The cosmological constant
problem is solved by introducing a fundamental quantum gravity scale,
$\Lambda_G\leq 10^{-4}$ eV, above which the virtual contributions to the vacuum
energy density coupled to gravity are exponentially suppressed, yielding an
observationally acceptable value for the particle physics contribution to the
cosmological constant. Classical Einstein gravity retains its causal behavior
as well as the standard agreement with observational data. Possible
experimental tests of the onset of quantum nonlocality at short distances are
considered.

</DOC>
<DOC>
<DOCNO> 170553 </DOCNO>
Characterising a universal cloning machine by maximum-likelihood


  We apply a general method for the estimation of completely positive maps to
the 1-to-2 universal covariant cloning machine. The method is based on the
maximum-likelihood principle, and makes use of random input states, along with
random projective measurements on the output clones. The downhill simplex
algorithm is applied for the maximisation of the likelihood functional.

</DOC>
<DOC>
<DOCNO> 99863 </DOCNO>
On the Soliton Geometry in Multidimensions


  Some aspects of the multidimensional soliton geometry are considered.

</DOC>
<DOC>
<DOCNO> 13477 </DOCNO>
Diamagnetic Response of Normal-Superconducting Double Layers


  The diamagnetism of a normal metal (N: Cu or Au), which is induced by the
proximity effect of a superconductor (S: Nb), has been investigated for N-S
double layers, which are formed by a thin-film deposition process. Detailed
studies of samples, which have different electronic mean-free path \ell_N in N,
suggest that \ell_N should be controlled by the impurity concentration rather
than the mechanical imperfections in the lattice in order to clarify the \ell_N
dependence of the proximity effect. Both the screening distance \rho in N and
the parameter \nu in \rho \propto T^-\nu increase with an increase in \ell_N.
This result can be understood on the assumption that the normal metal changes
its behavior from the "dirty" limit (\xi_N>\ell_N) to the "clean" limit
(\xi_N<\ell_N), where \xi_N is the coherence length in N.

</DOC>
<DOC>
<DOCNO> 100518 </DOCNO>
Homology for irregular connections


  Homology with values in a connection with possibly irregular singular points
on an algebraic curve is defined, generalizing homology with values in the
underlying local system for a connection with regular singular points.
Integration defines a perfect pairing between de Rham cohomology with values in
the connection and homology with values in the dual connection.

</DOC>
<DOC>
<DOCNO> 150842 </DOCNO>
A Note on Warped String Compactification


  We give a short review of a large class of warped string geometries, obtained
via F-theory compactified on Calabi-Yau fourfolds, that upon reduction to 5
dimensions give consistent supersymmetric realizations of the RS
compactification scenario.

</DOC>
<DOC>
<DOCNO> 11452 </DOCNO>
The Casimir Problem of Spherical Dielectrics: Quantum Statistical and


  The Casimir free energy for a system of two dielectric concentric nonmagnetic
spherical bodies is calculated with use of a quantum statistical mechanical
method, at arbitrary temperature. By means of this rather novel method, which
turns out to be quite powerful (we have shown this to be true in other
situations also), we consider first an explicit evaluation of the free energy
for the static case, corresponding to zero Matsubara frequency ($n=0$).
Thereafter, the time-dependent case is examined. For comparison we consider the
calculation of the free energy with use of the more commonly known field
theoretical method, assuming for simplicity metallic boundary surfaces.

</DOC>
<DOC>
<DOCNO> 170447 </DOCNO>
Preserving entanglement under decoherence and sandwiching all separable


  Every entangled state can be perturbed, for instance by decoherence, and stay
entangled. For a large class of pure entangled states, we show how large the
perturbation can be. Our class includes all pure bipartite and all maximally
entangled states. For an entangled state, E, the constucted neighborhood of
entangled states is the region outside two parallel hyperplanes, which sandwich
the set of all separable states. The states for which these neighborhoods are
largest are the maximally entangled ones. As the number of particles, or the
dimensions of the Hilbert spaces for two of the particles increases, the
distance between two of the hyperplanes which sandwich the separable states
goes to zero. It is easy to decide if a state Q is in the neighborhood of
entangled states we construct for an entangled state E. One merely has to check
if the trace of EQ is greater than a constant which depends upon E and which we
determine.

</DOC>
<DOC>
<DOCNO> 119806 </DOCNO>
Dwarf Galaxy Rotation Curves and the Core Problem of Dark Matter Halos


  The standard cold dark matter (CDM) model has recently been challenged by the
claim that dwarf galaxies have dark matter halos with constant density cores.
Consequently, numerous alternative dark matter candidates have recently been
proposed. In this paper, we scrutinize the observational evidence for the
incongruity between dwarf galaxies and the CDM model. To this end, we analyze
the rotation curves of 20 late-type dwarf galaxies studied by Swaters (1999).
Taking the effects of beam-smearing and adiabatic contraction into account, we
fit mass models to these rotation curves with dark matter halos with different
cusp slopes, ranging from constant density cores to r^{-2} cusps. Uncertainties
in the stellar mass-to-light ratio and the limited spatial sampling of the
halo's density distribution hamper a unique mass decomposition. Consequently,
the rotation curves in our sample cannot be used to discriminate between dark
halos with constant density cores and r^{-1} cusps. We show that the dwarf
galaxies analyzed here are consistent with cold dark matter halos in a LCDM
cosmology, and that there is thus no need to abandon the idea that dark matter
is cold and collisionless. However, the data is also consistent with any
alternative dark matter model that produces dark matter halos with central
cusps less steep than r^{-1.5}. In fact, we argue that based on existing
rotation curves alone at best weak limits can be obtained on cosmological
parameters and/or the nature of the dark matter.

</DOC>
<DOC>
<DOCNO> 116580 </DOCNO>
Polarization Dependence of Emissivity


  We deduce the emissivity of radiation from a metallic surface as a function
of angle and polarization. This effect has found application in the calibration
of detectors for cosmic microwave background radiation.

</DOC>
<DOC>
<DOCNO> 170411 </DOCNO>
Universal Holonomic Quantum Computing and Imperfections


  We present a non-local construction of universal gates by means of holonomic
(geometric) quantum teleportation. The effect of the errors from an imperfect
control of the classical parameters, the looping variation of which builds up
holonomic gates, is investigated. Additionally, the influence of quantum
decoherence on holonomic teleportation used as a computational primitive is
studied. Advantages of the holonomic implementation with respect to control
errors and dissipation are presented.

</DOC>
<DOC>
<DOCNO> 67668 </DOCNO>
Quarkonium momentum distributions in photoproduction and B decay


  According to our present understanding many $J/\psi$ production processes
proceed through a coloured $c\bar{c}$ state followed by the emission of soft
particles in the quarkonium rest frame. The kinematic effect of soft particle
emission is usually a higher-order effect in the non-relativistic expansion,
but becomes important near the kinematic endpoint of quarkonium energy
(momentum) distributions. In an intermediate region a systematic resummation of
the non-relativistic expansion leads to the introduction of so-called `shape
functions'. In this paper we provide an implementation of the kinematic effect
of soft gluon emission which is consistent with the non-relativistic shape
function formalism in the region where it is applicable and which models the
extreme endpoint region. We then apply the model to photoproduction of $J/\psi$
and $J/\psi$ production in $B$ meson decay. A satisfactory description of $B$
decay data is obtained. For inelastic charmonium photoproduction we conclude
that a sensible comparison of theory with data requires a transverse momentum
cut larger than the currently used 1 GeV.

</DOC>
<DOC>
<DOCNO> 71523 </DOCNO>
Ambiguities of theoretical parameters and CP/T violation in neutrino


  We study the sensitivity to the CP/T-violation search in the presence of
ambiguities of the theoretical parameters. Three generations of neutrinos are
considered. The parameters whose ambiguities are considered are the differences
of the squared masses, the mixing angles, and the density of matter.
 We first consider the statistics that are sensitive to the genuine
CP-violation effect originating from the imaginary coupling. No ambiguity of
the parameters is considered in this part. It is argued that the widely-adopted
usual statistics are not necessarily sensitive to the genuine CP-violation
effect. Two statistics that are sensitive to the imaginary coupling are
proposed. The qualitative difference between these statistics and the usual one
are discussed.
 Next we proceed to the case where the ambiguity of the parameters is present.
The sensitivity of the CP-violation search is greatly spoiled when the baseline
length is longer than about one thousand kilometers, which turns out to be due
to the ambiguity of the matter effect. Thus the CP-violation search by use of
CP conjugate channels turns out to require a low energy neutrino and short
baseline length. It is also shown that such a loss of sensitivity is avoided by
using T-conjugate oscillation channels.

</DOC>
<DOC>
<DOCNO> 102408 </DOCNO>
A Note Concerning the Turbulent Boundary Layer Drag at Large Reynolds


  A correlation is obtained for the drag coefficient $c '_f$ of the turbulent
boundary layer as a function of the effective boundary layer Reynolds number
$Re$ that we previously introduced. A comparison is performed also with another
correlation for the drag coefficient as a function of the traditional Reynolds
number $Re_{\th}$, based on the momentum thickness of the boundary layer
proposed recently by R.D.Watson, R.M.Hall and J.B.Anders (NASA Langley Research
Center) on the basis of different set of experimental data. We show that the
correlation obtained by us agrees with experimental data from the Illinois
Institute of Technology, but is incompatible with the data obtained in the
Royal Institute of Technology at Stockholm. On the other hand, both sets of
data are in disagreement with the Langley correlation.

</DOC>
<DOC>
<DOCNO> 122315 </DOCNO>
X-ray intensity-hardness correlation in Cyg X-1


  Using data from the All-Sky Monitor aboard the Rossi X-ray Timing Explorer
(RXTE), we found that the 1.5-12 keV X-ray count rate of Cyg X-1 is, on time
scales from 90 seconds to at least 10 days, strongly correlated with the
spectral hardness of the source in the soft state, but is weakly
anti-correlated with the latter in the hard state. The correlation shows an
interesting evolution during the 1996 spectral state transition. The entire
episode can be roughly divided into three distinct phases: (1) a 20-d
transition phase from the hard state to the soft state, during which the
correlation changes from being negative to positive, (2) a 50-d soft state with
a steady positive correlation, and (3) a 20-d transition back to the hard
state. The pointed RXTE observations confirmed the ASM results but revealed new
behaviors of the source at energies beyond the ASM pass band. We discuss the
implications of our findings.

</DOC>
<DOC>
<DOCNO> 69945 </DOCNO>
Vacuum instability in the Abelian Higgs model with strings


  Using the effective potential approach for composite operators, we have
analytically evaluated the truly nonperturbative vacuum energy density in the
Abelian Higgs model of dual QCD ground state. This quantity is defined as
integrating out of the truly nonperturbative part of the full gluon propagator
over the deep infrared region (soft momentum region). Defined in this way it is
manifestly gauge invariant.We have explicitly shown that the corresponding
effective potential always has an imaginary part. This means that the vacuum of
this model with string contributions is unstable against quantum corrections.

</DOC>
<DOC>
<DOCNO> 178491 </DOCNO>
Correlation energy of the pairing Hamiltonian


  We study the correlation energy associated with the pair fluctuations in BCS
theory. We use a schematic two-level pairing model and discuss the behavior of
the correlation energy across shell closures, including the even-odd
differences. It is shown that the random phase approximation (RPA) to the
ground state energy reproduces the exact solutions quite well both in the
normal fluid and in the superfluid phases. In marked contrast, other methods to
improve the BCS energies such as Lipkin-Nogami method, only work when the
strength of a pairing interaction is large. We thus conclude that the RPA
approach is better for a systematic theory of nuclear binding energies.

</DOC>
<DOC>
<DOCNO> 68728 </DOCNO>
Probing top flavour-changing neutral scalar couplings at the CERN LHC


  Top decays into a light Higgs boson and an up or charm quark can reach
detectable levels in Standard Model extensions with two Higgs doublets or with
new exotic quarks, and in the Minimal Supersymmetric Standard Model. Using both
a standard and a neural network analysis we show that the CERN Large Hadron
Collider will give 3 sigma evidence of decays with Br(t -> Hc) >= 6.5 10^-5 or
set a limit Br(t -> Hc) <= 4.5 10^-5 with a 95% confidence level if these
decays are not observed. We also consider limits obtained from single top
production associated with a neutral Higgs boson.

</DOC>
<DOC>
<DOCNO> 71174 </DOCNO>
Finite sum of gluon ladders and high energy cross sections


  A model for the Pomeron at $t=0$ is suggested. It is based on the idea of a
finite sum of ladder diagrams in QCD. Accordingly, the number of $s$-channel
gluon rungs and correspondingly the powers of logarithms in the forward
scattering amplitude depends on the phase space (energy) available, i.e. as
energy increases, progressively new prongs with additional gluon rungs in the
$s$-channel open. Explicit expressions for the total cross section involving
two and three rungs or, alternatively, three and four prongs (with $\ln^2(s)$
and $\ln^3(s)$ as highest terms, respectively) are fitted to the proton-proton
and proton-antiproton total cross section data in the accelerator region. Both
QCD calculation and fits to the data indicate fast convergence of the series.
In the fit, two terms (a constant and a logarithmically rising one) almost
saturate the whole series, the $\ln^2(s)$ term being small and the next one,
$\ln^3(s)$, negligible. Theoretical predictions for the photon-photon total
cross section are also given.

</DOC>
<DOC>
<DOCNO> 120441 </DOCNO>
Spillover and diffraction sidelobe contamination in a double-shielded


  We have analyzed observations from a radioastronomical experiment to survey
the sky at decimetric wavelengths along with feed pattern measurements in order
to account for the level of ground contamination entering the sidelobes. A
major asset of the experiment is the use of a wire mesh fence around the
rim-halo shielded antenna with the purpose of levelling out and reducing this
source of stray radiation for zenith-centered 1-rpm circular scans. We
investigate the shielding performance of the experiment by means of a geometric
diffraction model in order to predict the level of the spillover and
diffraction sidelobes in the direction of the ground. Using 408 MHz and 1465
MHz feed measurements, the model shows how a weakly-diffracting and unshielded
antenna configuration becomes strongly-diffracting and double-shielded as
far-field diffraction effects give way to near-field ones. Due to the
asymmetric response of the feeds, the orientation of their radiation fields
with respect to the secondary must be known a priori before comparing model
predictions with observational data. By adjusting the attenuation coefficient
of the wire mesh the model is able to reproduce the amount of differential
ground pick-up observed during test measurements at 1465 MHz.

</DOC>
<DOC>
<DOCNO> 84208 </DOCNO>
There is no spooky action-at-a-distance in quantum correlations:


  The long-standing puzzle of the nonlocal Einstein-Podolsky-Rosen correlations
is resolved. The correct quantum mechanical correlations arise for the case of
entangled particles when strict locality is assumed for the probability
amplitudes instead of locality for probabilities. Locality of amplitudes
implies that measurement on one particle does not collapse the companion
particle to a definite state.

</DOC>
<DOC>
<DOCNO> 118697 </DOCNO>
Massive star formation and evolution in starburst galaxies: mid-infrared


  We present new ISO-SWS data for a sample of 27 starburst galaxies, and with
these data examine the issues of formation and evolution of the most massive
stars in starburst galaxies. Using starburst models which incorporate time
evolution, new stellar atmosphere models for massive stars, and a starburst
model geometry derived from observations of the prototypical starburst M82, we
model the integrated mid-infrared line ratio [NeIII](15.6 microns)/[NeII](12.8
microns). This line ratio is sensitive to the hardness of the stellar energy
distribution and therefore to the most massive stars present.
  We conclude from our models, with consideration of recent determinations of
the stellar census in local, high-mass star forming regions, that the
[NeIII]/[NeII] ratios we measure are consistent with the formation of massive
(~50-100 solar mass) stars in most starbursts. In this framework, the low
nebular excitation inferred from the measured line ratios can be attributed to
aging effects. By including estimates of the ratio of infrared-to-Lyman
continuum luminosity for the galaxies in our sample, we further find that most
starbursts are relatively short-lived (1-10 million years), only a few O-star
lifetimes. We discuss a possible cause of such short events: the effectiveness
of stellar winds and supernovae in destroying the starburst environment.

</DOC>
<DOC>
<DOCNO> 169898 </DOCNO>
Quantum Noise and Superluminal Propagation


  Causal "superluminal" effects have recently been observed and discussed in
various contexts. The question arises whether such effects could be observed
with extremely weak pulses, and what would prevent the observation of an
"optical tachyon." Aharonov, Reznik, and Stern (ARS) [Phys. Rev. Lett., vol.
81, 2190 (1998)] have argued that quantum noise will preclude the observation
of a superluminal group velocity when the pulse consists of one or a few
photons. In this paper we reconsider this question both in a general framework
and in the specific example, suggested by Chiao, Kozhekin, and Kurizki [Phys.
Rev. Lett., vol. 77, 1254 (1996)], of off-resonant, short-pulse propagation in
an optical amplifier. We derive in the case of the amplifier a signal-to-noise
ratio that is consistent with the general ARS conclusions when we impose their
criteria for distinguishing between superluminal propagation and propagation at
the speed c. However, results consistent with the semiclassical arguments of
CKK are obtained if weaker criteria are imposed, in which case the signal can
exceed the noise without being "exponentially large." We show that the quantum
fluctuations of the field considered by ARS are closely related to
superfluorescence noise. More generally we consider the implications of
unitarity for superluminal propagation and quantum noise and study, in addition
to the complete and truncated wavepackets considered by ARS, the residual
wavepacket formed by their difference. This leads to the conclusion that the
noise is mostly luminal and delayed with respect to the superluminal signal. In
the limit of a very weak incident signal pulse, the superluminal signal will be
dominated by the noise part, and the signal-to-noise ratio will therefore be
very small.

</DOC>
<DOC>
<DOCNO> 8909 </DOCNO>
Nonlinear electrodynamics of p-wave superconductors


  We consider the Maxwell-London electrodynamics of three dimensional
superconductors in p-wave pairing states with nodal points or lines in the
energy gap. The current-velocity relation is then nonlinear in the applied
field, cubic for point nodes and quadratic for lines. We obtain explicit
angular and depth dependent expressions for measurable quantities such as the
transverse magnetic moment, and associated torque. These dependences are
different for point and line nodes and can be used to distinguish between
different order parameters. We discuss the experimental feasibility of this
method, and bring forth its advantages, as well as limitations that might be
present.

</DOC>
<DOC>
<DOCNO> 119700 </DOCNO>
The velocity field of young stars in the solar neighbourhood


  A sample of O- and B-type stars with Hipparcos astrometric data, ages
computed from Str\"omgren photometry and radial velocities, has been used to
characterize the structure, age and kinematics of the Gould Belt system. The
local spiral structure of our galaxy is determined from this sample, and also
from a sample of Hipparcos Cepheid stars.
  The Gould Belt, with an orientation with respect to the galactic plane of
$i_{\mathrm{G}} = 16$-$22^\circ$ and $\Omega_{\mathrm{G}} = 275$-$295^\circ$,
extends up to a distance of 600 pc from the Sun. Roughly the 60-65% of the O
and B stars younger than 60 Myr in the solar neighbourhood belong to this
structure. Our results indicate that the kinematical behaviour of this system
is complex, with an expansion motion in the solar neighbourhood ($R <$ 300 pc).
  In the frame of the Lin's theory, and analysing the O and B stars further
than 600 pc and the Cepheids, we found a galactic spiral structure
characterized by a 4-arm spiral pattern with the Sun located at $\psi_\odot =
350$-$355 \pm 30^\circ$ -- near the Sagittarius-Carina arm -- and outside the
corotation circle. The angular rotation speed of the spiral pattern was found
to be $\Omega_{\mathrm{p}} = 31$-$32 \pm 4$ km s$^{-1}$ kpc$^{-1}$.

</DOC>
<DOC>
<DOCNO> 10984 </DOCNO>
Josephson Effect Without Superconductivity: Realization in Quantum Hall


  We show that a quantum Hall bilayer with the total filling $\nu = 1$ should
exhibit a dynamical regime similar to the flux-flow in large Josephson
junctions. This analogy may explain a conspicuous peak in the interlayer
tunneling conductance [\prl {\bf 84}, 5808 (2000)]. The flux-flow is likely to
be spatiotemporally chaotic at low bias voltage, which will manifest itself
through broad-band noise. The peak position can be controlled by an in-plane
magnetic field.

</DOC>
<DOC>
<DOCNO> 102706 </DOCNO>
Estimating the p-variation index of a sample function: An application to


  This paper modifies a box-counting method of estimating a fractal dimension
of a graph, and applies it to estimate the roughness of a sample function of a
stochastic process such as a Levy process or a Gaussian process with stationary
increments

</DOC>
<DOC>
<DOCNO> 13593 </DOCNO>
Phonon-assisted tunneling in the quantum regime of Mn12-ac


  Longitudinal or transverse magnetic fields applied on a crystal of Mn12-ac
allows to observe independent tunnel transitions between m=-S+p and m=S-n-p
(n=6-10, p=0-2 in longitudinal field and n=p=0 in transverse field). We observe
a smooth transition (in longitudinal) from coherent ground-state to thermally
activated tunneling. Furthermore two ground-state relaxation regimes showing a
crossover between quantum spin relaxation far from equilibrium and near
equilibrium, when the environment destroys multimolecule correlations. Finally,
we stress that the complete Hamiltonian of Mn12 should contain odd spin
operators of low order.

</DOC>
<DOC>
<DOCNO> 100744 </DOCNO>
Nonlinear wave equation, nonlinear Riemann problem, and the twistor


  Veronese webs are rich geometric structures with deep relationships to
various domains of mathematics. The PDEs which determine the Veronese web are
overdetermined if dim >3, but in the case dim =3 they reduce to a special
flavor of a non-linear wave equation. The symmetries embedded in the definition
of a Veronese web reveal themselves as B\"acklund--Darboux transformations
between these non-linear wave equations.
  On the other hand, the twistor transform identifies Veronese webs with moduli
spaces of rational curves on certain complex surfaces. These moduli spaces can
be described in terms of the non-linear Riemann problem. This reduces solutions
of these non-linear wave equations to the non-linear Riemann problem.
  We examine these relationships in the particular case of 3-dimensional
Veronese webs, simultaneously investigating how these notions relate to general
notions of geometry of webs.

</DOC>
<DOC>
<DOCNO> 122107 </DOCNO>
Color Correlations in (S+S) Binary Galaxies I. The Holmberg Effect


  Relying on his photometry of galaxies, Holmberg (1958) found, more than 40
years ago, that the color indices of paired galaxies were closely correlated.
Our deep broad-band BVRI CCD photometry of 45 (S+S) pairs from the Karachentsev
(1972) catalogue (see Hernandez Toledo and Puerari, this volume), and
additional (B-V) color information from the literature (50 extra (S+S) pairs),
help us to confirm the effect. This "Holmberg Effect" has long been remained
unverified and not explained yet.

</DOC>
<DOC>
<DOCNO> 152287 </DOCNO>
New symplectic structure for KdV


  Starting with Lagrangians, which turn out to be degenerate, the Hamiltonian
operators for integrable systems can be constructed using Dirac's theory of
constraints. We illustrate this by giving a systematic discussion of the first
Hamiltonian structure of KdV. The first symplectic 2-form obtained from Dirac's
theory is the time component of the covariant Witten-Zuckerman symplectic
2-form current. We derive the flux of the first symplectic 2-form. Then we turn
to a new Lagrangian for KdV recently obtained by Pavlov and present the
corresponding new covariant symplectic structure for KdV. This shows that the
inverse of Magri's second Hamiltonian operator is also a Hamiltonian operator
for KdV.

</DOC>
<DOC>
<DOCNO> 101731 </DOCNO>
Path integral formulation of constrained systems with singular-higher


  Systems with singular higher order- Lagrangians are investigated by using the
extended form of the canonical method. Besides, the canonical path integral
formulation is generalized using the Hamilton- jacobi formulation to
investigate singular systems

</DOC>
<DOC>
<DOCNO> 85430 </DOCNO>
On line power spectra identification and whitening for the noise in


  In this paper we address both to the problem of identifying the noise Power
Spectral Density of interferometric detectors by parametric techniques and to
the problem of the whitening procedure of the sequence of data. We will
concentrate the study on a Power Spectral Density like the one of the
Italian-French detector VIRGO and we show that with a reasonable finite number
of parameters we succeed in modeling a spectrum like the theoretical one of
VIRGO, reproducing all its features. We propose also the use of adaptive
techniques to identify and to whiten on line the data of interferometric
detectors. We analyze the behavior of the adaptive techniques in the field of
stochastic gradient and in the
 Least Squares ones.

</DOC>
<DOC>
<DOCNO> 40280 </DOCNO>
First Observation of the Decays $B^{0}\to D^{*-}p\bar{p}\pi^{+}$ and


  We report the first observation of exclusive decays of the type B to D^* N
anti-N X, where N is a nucleon. Using a sample of 9.7 times 10^{6} B-Bbar pairs
collected with the CLEO detector operating at the Cornell Electron Storage
Ring, we measure the branching fractions B(B^0 \to D^{*-} proton antiproton
\pi^+) = ({6.5}^{+1.3}_{-1.2} +- 1.0) \times 10^{-4} and B(B^0 \to D^{*-}
proton antineutron) = ({14.5}^{+3.4}_{-3.0} +- 2.7) times 10^{-4}. Antineutrons
are identified by their annihilation in the CsI electromagnetic calorimeter.

</DOC>
<DOC>
<DOCNO> 12698 </DOCNO>
Soft Interaction Between Dissolved Dendrimers: Theory and Experiment


  Using small-angle neutron scattering and liquid integral equation theory, we
relate the structure factor of flexible dendrimers of 4th generation to their
average shape. The shape is measured as a radial density profile of monomers
belonging to a single dendrimer. From that, we derive an effective interaction
of Gaussian form between pairs of dendrimers and compute the structure factor
using the hypernetted chain approximation. Excellent agreement with the
corresponding experimental results is obtained, without the use of adjustable
parameters. The present analysis thus strongly supports the previous finding
that flexible dendrimers of low generation present fluctuating structures akin
to star polymers.

</DOC>
<DOC>
<DOCNO> 71678 </DOCNO>
Primordial magnetic fields from inflation???


  In this note we argue that the breaking of conformal invariance because of
the coupling of a charged scalar field to gravity is not sufficient for the
production of seed galactic magnetic fields during inflation.

</DOC>
<DOC>
<DOCNO> 70071 </DOCNO>
Parton Densitites at High-x


  Reliable knowledge of parton distributions at large x is crucial for many
searches for new physics signals in the next generation of collider
experiments. Although these are generally well determined in the small and
medium x range, it has been shown that their uncertainty grows rapidly for
x>0.1. We examine the status of the distributions in light of new questions
that have been raised about "large-x" parton distributions, as well as recent
measurements which have improved the parton uncertainties.

</DOC>
<DOC>
<DOCNO> 101441 </DOCNO>
The distributions of the entries of Young tableaux


  Let T^* be a standard Young tableau of k cells. We show that the probability
that a Young tableau of n cells contains T^* as a subtableau is, in the limit n
-> \infty, equal to \nu(\pi(T^*))/k!, where \pi(T^*) is the shape (= Ferrers
diagram) of T^* and \nu(\pi) is the number of all tableaux of shape \pi. In
other words, the probability that a large tableau contains T^* is equal to the
number of tableaux whose shape is that of T^*, divided by k!.
  We give several applications, to the probabilities that a set of prescribed
entries will appear in a set of prescribed cells of a tableau, and to the
probabilities that subtableaux of given shapes will occur.
  Our argument rests on a notion of quasirandomness of families of
permutations, and we give sufficient conditions for this to hold. We then
extend these results by finding an explicit formula for the limiting
probability that a Young tableau has a given set of entries in a given set of
positions. The result is that the limiting probability that a Young tableau has
a prescribed set of entries k_1,k_2,..., k_m in a prescribed set of m cells is
equal to the sum of the measures of all tableaux on K cells (K=\max{\{k_i\}})
that have the given entries in the given positions, where the measure of a
tableau of K cells is the number of tableaux of its shape divided by K!.
  In the proof we also develop conditions that ensure the quasirandomness of
certain families of permutations.

</DOC>
<DOC>
<DOCNO> 101851 </DOCNO>
A probabilistic algorithm to test local algebraic observability in


  The following questions are often encountered in system and control theory.
Given an algebraic model of a physical process, which variables can be, in
theory, deduced from the input-output behavior of an experiment? How many of
the remaining variables should we assume to be known in order to determine all
the others? These questions are parts of the \emph{local algebraic
observability} problem which is concerned with the existence of a non trivial
Lie subalgebra of the symmetries of the model letting the inputs and the
outputs invariant. We present a \emph{probabilistic seminumerical} algorithm
that proposes a solution to this problem in \emph{polynomial time}. A bound for
the necessary number of arithmetic operations on the rational field is
presented. This bound is polynomial in the \emph{complexity of evaluation} of
the model and in the number of variables. Furthermore, we show that the
\emph{size} of the integers involved in the computations is polynomial in the
number of variables and in the degree of the differential system. Last, we
estimate the probability of success of our algorithm and we present some
benchmarks from our Maple implementation.

</DOC>
<DOC>
<DOCNO> 10239 </DOCNO>
Controlling the Size of Popcorn


  We present a thermo-statistical model of popcorn production and propose a way
to control the final size of the popcorn by monitoring only the chamber
pressure.

</DOC>
<DOC>
<DOCNO> 100053 </DOCNO>
Matching and digital control implementation for underactuated systems


  This note describes two problems related to the digital implementation of
control laws in the infinite dimensional family of matching control laws,
namely state estimation and sampled data induced error. The entire family of
control laws is written for an inverted pendulum cart. Numerical simulations
which include sampled data and a state estimator are presented for one of the
control laws in this family.

</DOC>
<DOC>
<DOCNO> 10315 </DOCNO>
Conduction through a quantum dot near a singlet-triplet transition


  Kondo effect in the vicinity of a singlet-triplet transition in a vertical
quantum dot is considered. This system is shown to map onto a special version
of the two-impurity Kondo model. At any value of the control parameter, the
system has a Fermi-liquid ground state. Explicit expressions for the linear
conductance as a function of the control parameter and temperature $T$ are
obtained. At T=0, the conductance reaches the unitary limit $\sim 4e^2/h$ at
the triplet side of the transition, and decreases with the increasing distance
to the transition at the singlet side. At finite temperature, the conductance
exhibits a peak near the transition point.

</DOC>
<DOC>
<DOCNO> 9849 </DOCNO>
Magnetization plateaus in antiferromagnetic-(ferromagnetic)_{n}


  The plateau-non-plateau transition in the
antiferromagnetic-(ferromagnetic)$_{n}$ polymerized $S=1/2$ XXZ chains under
the magnetic field is investigated. The universality class of this transition
belongs to the Brezinskii-Kosterlitz-Thouless (BKT) type. The critical points
are determined by level spectroscopy analysis of the numerical diagonalization
data for $4 \leq p \leq 13$ where $p(\equiv n+1)$ is the size of a unit cell.
It is found that the critical strength of ferromagnetic coupling decreases with
$p$ for small $p$ but increases for larger enough $p$. It is also found that
the plateau for large $p$ is wide enough for moderate values of exchange
coupling so that it should be easily observed experimentally. This is in
contrast to the plateaus for $p = 3$ chains which are narrow for a wide range
of exchange coupling even away from the critical point.

</DOC>
<DOC>
<DOCNO> 85515 </DOCNO>
Magnetic tension and the geometry of the universe


  The vector nature of magnetic fields and the geometrical interpretation of
gravity introduced by general relativity, guarantee a special coupling between
magnetism and spacetime curvature. This magneto-geometrical interaction
effectively transfers the tension properties of the field into the spacetime
fabric, triggering a variety of effects with profound implications. Given the
ubiquity of magnetic fields in the universe, these effects could prove
critical. We discuss the nature of the magneto-curvature coupling and
illustrate some of its potential implications for cosmology.

</DOC>
<DOC>
<DOCNO> 117327 </DOCNO>
Multi-filament structures in relativistic self-focusing


  A simple model is derived to prove the multi-filament structure of
relativistic self-focusing with ultra-intense lasers. Exact analytical
solutions describing the transverse structure of waveguide channels with
electron cavitation, for which both the relativistic and ponderomotive
nonlinearities are taken into account, are presented.

</DOC>
<DOC>
<DOCNO> 101347 </DOCNO>
On Poly(ana)logs I


  We investigate a connection between the differential of polylogarithms (as
considered by Cathelineau) and a finite variant of them. This allows to answer
a question raised by Kontsevich concerning the construction of functional
equations for the finite analogs, using in part the p-adic version of
polylogarithms and recent work of Besser. 
  Kontsevich's original unpublished note is supplied (with his kind permission)
in an "Appendix" at the end of the paper.

</DOC>
<DOC>
<DOCNO> 9428 </DOCNO>
Pulling a polymer out of a potential well and the mechanical unzipping


  Motivated by the experiments on DNA under torsion, we consider the problem of
pulling a polymer out of a potential well by a force applied to one of its
ends. If the force is less than a critical value, then the process is activated
and has an activation energy proportinal to the length of the chain. Above this
critical value, the process is barrierless and will occur spontaneously. We use
the Rouse model for the description of the dynamics of the peeling out and
study the average behaviour of the chain, by replacing the random noise by its
mean. The resultant mean-field equation is a nonlinear diffusion equation and
hence rather difficult to analyze. We use physical arguments to convert this in
to a moving boundary value problem, which can then be solved exactly. The
result is that the time $t_{po}$ required to pull out a polymer of $N$ segments
scales like $N^2$. For models other than the Rouse, we argue that $t_{po}\sim
N^{1+\nu}$

</DOC>
<DOC>
<DOCNO> 80986 </DOCNO>
Overlap Fermions on a $20^4$ Lattice


  We report results on hadron masses, fitting of the quenched chiral log, and
quark masses from Neuberger's overlap fermion on a quenched $20^4$ lattice with
lattice spacing $a = 0.15$ fm. We used the improved gauge action which is shown
to lower the density of small eigenvalues for $H^2$ as compared to the Wilson
gauge action. This makes the calculation feasible on 64 nodes of CRAY-T3E. Also
presented is the pion mass on a small volume ($6^3 \times 12$ with a Wilson
gauge action at $\beta = 5.7$). We find that for configurations that the
topological charge $Q \ne 0$, the pion mass tends to a constant and for
configurations with trivial topology, it approaches zero possibly linearly with
the quark mass.

</DOC>
<DOC>
<DOCNO> 85213 </DOCNO>
Data Analysis of Continuous Gravitational Wave Signal: Fourier Transform


  We present the Fourier Transform of continuous gravitational wave for
arbitrary location of detector and source and for any duration of observation
time in which both rotational motion of earth about its spin axis and orbital
motion around sun has been taken into account. We also give the method to
account the spin down of continuous gravitational wave.

</DOC>
<DOC>
<DOCNO> 8673 </DOCNO>
Classical phase space and statistical mechanics of identical particles


  Starting from the quantum theory of identical particles, we show how to
define a classical mechanics that retains information about the quantum
statistics. We consider two examples of relevance for the quantum Hall effect:
identical particles in the lowest Landau level, and vortices in the
Chern-Simons Ginzburg-Landau model. In both cases the resulting {\em classical}
statistical mechanics is shown to be a nontrivial classical limit of Haldane's
exclusion statistics.

</DOC>
<DOC>
<DOCNO> 100957 </DOCNO>
Asymptotic behaviour of solutions of fourth order Dirichlet problems


  The behaviour of solutions to fourth order problems is studied through the
decomposition into a system of second order ones, which leads to relaxed
formulations with the introduction of measure terms. This allows to solve a
shape optimization problem for a simply supported thin plate.

</DOC>
<DOC>
<DOCNO> 100854 </DOCNO>
Polysymplectic spaces, s-Kahler manifolds and lagrangian fibrations


  In the first part of this paper we begin the study of polysymplectic
manifolds, and of their relationship with PDE's. This notion provides a
generalization of symplectic manifolds which is very well suited for the
geometric study of PDE's with values in a smooth manifold. Some of the standard
tools of analytical mechanics, such as the Legendre transformation and
Hamilton's equations, are shown to generalize to this new setting. There is a
strong link with lagrangian fibrations, which can be used to build
polysymplectic manifolds. We then provide the definition and some basic
properties of s-Kahler and almost s-Kahler manifolds. These are a
generalization of the usual notion of Kahler and almost Kahler manifold, and
they reduce to them for s=1. The basic properties of Kahler manifolds, and
their Hodge theory, can be generalized to s-Kahler manifolds, with some
modifications. The most interesting examples come from semi-flat special
lagrangian fibrations of Calabi-Yau manifolds.

</DOC>
<DOC>
<DOCNO> 39795 </DOCNO>
The Dark Side of the Solar Neutrino Parameter Space


  Results of neutrino oscillation experiments have always been presented on the
(sin^2 2theta, Delta m^2) parameter space for the case of two-flavor
oscillations. We point out, however, that this parameterization misses the half
of the parameter space pi/4 < theta <= pi/2 (``the dark side''), which is
physically inequivalent to the region 0 <= theta <= pi/4 (``the light side'')
in the presence of matter effects. The MSW solutions to the solar neutrino
problem can extend to the dark side, especially if we take the conservative
attitude to allow higher confidence levels, ignore some of the experimental
results in the fits, or relax theoretical predictions. Furthermore even the
so-called ``vacuum oscillation'' solution distinguishes the dark and the light
sides. We urge experimental collaborations to present their results on the
entire parameter space.

</DOC>
<DOC>
<DOCNO> 170003 </DOCNO>
Manipulating the frequency entangled states by


  In this paper, we describe how to realize conditional frequency entanglement
swapping and to produce probabilisticly a three-photon frequency entangled
state from two pairs of frequency entangled states by using an
Acoustic-Optical-Modulator. Both schemes are very simple and may be
implementable in practice.

</DOC>
<DOC>
<DOCNO> 69263 </DOCNO>
Dynamical Symmetry Breaking in Supersymmetric SU(n_c) and USp(2n_c)


  We find the phase and flavor symmetry breaking pattern of each N=1
supersymmetric vacuum of SU(n_c) and USp(2 n_c) gauge theories, constructed
from the exactly solvable N=2 theories by perturbing them with small adjoint
and generic bare hypermultiplet (quark) masses. In SU(n_c) theories with n_f
\leq n_c the vacua are labelled by an integer r, in which the flavor U(n_f)
symmetry is dynamically broken to U(r) \times U(n_f-r) in the limit of
vanishing bare hyperquark masses. In the r=1 vacua the dynamical symmetry
breaking is caused by the condensation of magnetic monopoles in the n_f
representation. For general r, however, the monopoles in the {}_{n_f}C_r
representation, whose condensation could explain the flavor symmetry breaking
but would produce too-many Nambu--Goldstone multiplets, actually "break up"
into "magnetic quarks": the latter with nonabelian interactions condense and
induce confinement and dynamical symmetry breaking. In USp(2n_c) theories with
n_f \leq n_c + 1, the flavor SO(2n_f) symmetry is dynamically broken to U(n_f),
but with no description in terms of a weakly coupled local field theory. In
both SU(n_c) and USp(2 n_c) theories, with larger numbers of quark flavors,
besides the vacua with these properties, there exist also vacua in free
magnetic phase, with unbroken global symmetry.

</DOC>
<DOC>
<DOCNO> 152125 </DOCNO>
Critical Phenomenon of a Consistent q-Deformed Squeezed State


  Within a self-consistent framework of q-deformed Heisenberg algebra and its
equivalent framework of q-deformed boson commutation relations, which relate to
the under-cutting phenomenon of Heisenberg's minimal uncertainty relation,
special q-deformed squeezed states are constructed. Besides the similar local
maximum squeezing as the one in the undeformed case, new strong squeezing
appears when the amplitude of the related coherent state increases to large
values. A critical phenomenon appears at a large value of the amplitude: the
variance of one component of the quadrature of the light field approaches zero,
but the variance of the corresponding conjugate quantity remains finite, which
is a surprising deviation from Heisenberg's uncertainty relation. The
qualitative character exposed by this q-squeezed state may provide some
evidence about q-deformed effects in current experiments.

</DOC>
<DOC>
<DOCNO> 10799 </DOCNO>
Parallel Excluded Volume Tempering for Polymer Melts


  We have developed a technique to accelerate the acquisition of effectively
uncorrelated configurations for off-lattice models of dense polymer melts which
makes use of both parallel tempering and large scale Monte Carlo moves. The
method is based upon simulating a set of systems in parallel, each of which has
a slightly different repulsive core potential, such that a thermodynamic path
from full excluded volume to an ideal gas of random walks is generated. While
each system is run with standard stochastic dynamics, resulting in an NVT
ensemble, we implement the parallel tempering through stochastic swaps between
the configurations of adjacent potentials, and the large scale Monte Carlo
moves through attempted pivot and translation moves which reach a realistic
acceptance probability as the limit of the ideal gas of random walks is
approached. Compared to pure stochastic dynamics, this results in an increased
efficiency even for a system of chains as short as $N = 60$ monomers, however
at this chain length the large scale Monte Carlo moves were ineffective. For
even longer chains the speedup becomes substantial, as observed from
preliminary data for $N = 200$.

</DOC>
<DOC>
<DOCNO> 117136 </DOCNO>
Magnetic Field Saturation in the Riga Dynamo Experiment


  After the dynamo experiment in November 1999 had shown magnetic field
self-excitation in a spiraling liquid metal flow, in a second series of
experiments emphasis was placed on the magnetic field saturation regime as the
next principal step in the dynamo process. The dependence of the strength of
the magnetic field on the rotation rate is studied. Various features of the
saturated magnetic field are outlined and possible saturation mechanisms are
discussed.

</DOC>
<DOC>
<DOCNO> 39803 </DOCNO>
Coherent Contributions of Nuclear Mesons to Electroproduction and the


  We show that nuclear sigma, omega, and pi mesons can contribute coherently to
enhance the electroproduction cross section on nuclei for longitudinal virtual
photons at low Q^2 while depleting the cross section for transverse photons. We
are able to describe recent HERMES inelastic lepton-nucleus scattering data at
low Q^2 and small x using photon-meson and meson-nucleus couplings which are
consistent with (but not determined by) existing constraints from meson decay
widths, nuclear structure, deep inelastic scattering, and lepton pair
production data. We find that while nuclear-coherent pion currents are not
important for the present data, they could be observed at different kinematics.
Our model for coherent meson electroproduction requires the assumption of
mesonic currents and couplings which can be verified in separate experiments.
The observation of nuclear-coherent mesons in the final state would verify our
theory and allow the identification of a specific dynamical mechanism for
higher-twist processes.

</DOC>
<DOC>
<DOCNO> 170740 </DOCNO>
Ponderomotive entanglement purification


  It is shown that ponderomotive force can be used to purify entangled states.
The protocol is based on the possibility to exploit such force for a local
quantum nondemolition measurement of the total excitation number of continuos
variable entangled pairs.

</DOC>
<DOC>
<DOCNO> 118523 </DOCNO>
A Rapid X-ray Flare from Markarian 501


  We present X-ray observations of the BL Lacertae (BL Lac) object Markarian
501 (Mrk 501), taken with the Rossi X-ray Timing Explorer in 1998 May as part
of a multi-wavelength campaign. The X-ray light curve shows a very rapid flare
in which the 2-10 keV flux increased by ~60% in <200 seconds. This rapid rise
is followed by a drop-off in the 2-10 keV flux of ~40% in <600 seconds. The
10-15 keV variation in this flare is roughly a factor of two on similar
time-scales. During the rise of the flare, the 3-15 keV spectral index hardened
from 2.02 +/- 0.03 to 1.87 +/- 0.04, where it remained during the decay of the
flare. This is the fastest variation ever seen in X-rays from Mrk 501 and among
the fastest seen at any wavelength for this object. The shift in the energy at
which the spectral power peaks (from <3 keV before the flare to >30 keV during
the flare) is also among the most rapid shifts seen from this object. This
flare occurs during an emission state (2-10 keV flux approximately 1.2e-10 erg
cm^-2 s^-1) that is approximately 25% of the peak flux observed in 1997 April
from this object but which is still high compared to its historical average
X-ray flux. The variations in the hardness ratio are consistent with the low
energy variations leading those at high energies during the development and
decay of the flare. This pattern is rare among high frequency peaked BL Lac
objects like Mrk 501, but has been seen recently in two other TeV emitting BL
Lacs, Mrk 421 and PKS 2155-304. The hard lag is consistent with a flare
dominated by the acceleration time-scale for a simple relativistic shock model
of flaring.

</DOC>
<DOC>
<DOCNO> 14045 </DOCNO>
Sign-time distribution for a random walker with a drifting boundary


  We present a derivation of the exact sign-time distribution for a random
walker in the presence of a boundary moving with constant velocity.

</DOC>
<DOC>
<DOCNO> 119598 </DOCNO>
Embedded Stellar Clusters in the W3/W4/W5 Molecular Cloud Complex


  We analyze the embedded stellar content in the vicinity of the W3/W4/W5 HII
regions using the FCRAO Outer Galaxy 12CO(J=1-0) Survey, the IRAS Point Source
Catalog, published radio continuum surveys, and new near-infrared and molecular
line observations. Thirty-four IRAS Point Sources are identified that have
far-infrared colors characteristic of embedded star forming regions, and we
have obtained K' mosaics and 13CO(J=1-0) maps for 32 of them. Ten of the IRAS
sources are associated with an OB star and 19 with a stellar cluster, although
three OB stars are not identified with a cluster. Half of the embedded stellar
population identified in the K' images is found in just the 5 richest clusters,
and 61% is contained in IRAS sources associated with an embedded OB star. Thus
rich clusters around OB stars contribute substantially to the stellar
population currently forming in the W3/W4/W5 region. Approximately 39% of the
cluster population is embedded in small clouds with an average mass of ~130 Mo
that are located as far as 100 pc from the W3/W4/W5 cloud complex. We speculate
that these small clouds are fragments of a cloud complex dispersed by previous
episodes of massive star formation. Finally, we find that 4 of the 5 known
embedded massive star forming sites in the W3 molecular cloud are found along
the interface with the W4 HII region despite the fact that most of the
molecular mass is contained in the interior regions of the cloud. These
observations are consistent with the classical notion that the W4 HII region
has triggered massive star formation along the eastern edge of the W3 molecular
cloud.

</DOC>
<DOC>
<DOCNO> 40025 </DOCNO>
Multimode gravitational wave detection: the spherical detector theory


  A spherical gravity wave (GW) detector, unlike interferometers and bars, is a
natural multi-mode device, i.e., it is capable of independently gathering
information on all five quadrupole and one monopole amplitudes of a general
incoming GW. This is because the sphere's degenerate oscillation eigenmodes are
uniquely matched to the structure of the GWs' Riemann tensor components.
Suitable linear combinations of the system readout channels completely
deconvolve the six GW amplitudes. The present article is concerned with the
theoretical reasons for the remarkable properties of a spherical GW detector.
The analysis proceeds from first principles and is based on essentially no 'ad
hoc' hypotheses. The mathematical beauty of the theory is outstanding, and
abundant detail is given for a thorough understanding of the fundamental facts
and ideas. Experimental evidence of the accuracy of the model is also provided,
where possible.

</DOC>
<DOC>
<DOCNO> 118725 </DOCNO>
Lyman Alpha Cooling Radiation from High-Redshift Halos


  The baryons inside high-redshift halos with virial temperatures above T=10^4
K cool radiatively as they condense inside dark matter potential wells. We show
that the release of the gravitational binding energy, over the halo assembly
time-scale, results in a significant and detectable Ly alpha flux. At the
limiting line flux of approximately 10^-19 erg/s/cm^2/asec^2 of the Next
Generation Space Telescope, several sufficiently massive halos, with velocity
dispersions above sigma=120 km/s, would be visible per 4'x4' field. The halos
would have characteristic angular sizes of approximately 10 asec, would be
detectable in a broad-band survey out to redshifts z=6-8, and would provide a
direct probe of galaxies in the process of forming. They may be accompanied by
HeII Ly alpha emission at the 10 percent level, but remain undetectable at
other wavelengths. Our predictions are in good agreement with the recent
finding of two Ly alpha ``blobs'' at z=3.1 by Steidel et al. (1999).

</DOC>
<DOC>
<DOCNO> 120144 </DOCNO>
The dusty SF history of distant galaxies and modelling tools


  I review recent advances in the determination of the cosmic history of star
formation, and its relevance in our understanding of the formation of
structures. I emphasize the importance of dust reprocessing in the high--z
universe, as demonstrated in particular by IR and sub-mm data. This demand a
panchromatic approach to observations and suitable modelling tools. I summarize
the basic requirements for these models and to what extent they are satisfied
by models published so far.

</DOC>
<DOC>
<DOCNO> 122271 </DOCNO>
Production of 2H, 3He, and 7Li from Interactions Between Jets and Clouds


  The interactions between jets of high-energy nuclei and nuclei of the
surrounding medium are studied. Such interactions could be initiated by jets
from active galactic nuclei interacting with surrounding cool clouds. The
resulting nuclear interactions are found to produce copious amounts of 2H and
3He from the 4He nuclei. These results suggest that jets of particles from
quasars could have produced anomalously high abundances in surrounding clouds
of some of the nuclides usually thought to characterize big bang
nucleosynthesis, specifically, the 2H seen in absorption spectra.

</DOC>
<DOC>
<DOCNO> 152610 </DOCNO>
Wave-function renormalization for the Coulomb-gas in Wegner-Houghton's


  The RG flow for the sine-Gordon model is determined by means of the method of
Wegner and Houghton in next-to-leading order of the derivative expansion. For
small values of the fugacity this agrees with the well-known RG flow of the
two-dimensional Coulomb-gas found in the dilute gas approximation and a
systematic way of obtaining higher-order corrections to this approximation is
given.

</DOC>
<DOC>
<DOCNO> 117806 </DOCNO>
Internal shock model for Microquasars


  We present a model for the radio outbursts of microquasars based on the
assumption of quasi-continuous jet ejection. The jets are `lit up' by shock
fronts traveling along the jets during outbursts. The observed comparatively
flat decay light curves combined with gradually steepening spectral slopes are
explained by a superposition of the radiation of the aging relativistic
particle population left behind by the shocks. This scenario is the low energy,
time-resolved equivalent to the internal shock model for GRBs. We show that
this model predicts energy contents of the radiating plasma similar to the
plasmon model. At the same time, the jet model relaxes the severe requirements
on the central source in terms of the rate at which this energy must be
supplied to the jet. Observations of `mini-bursts' with flat spectral slopes
and of infrared emission far from the source centre suggest two different
states of jet ejections: (i) A `mini-burst' mode with relatively stable jet
production and weak radio emission with flat spectra and (ii) an outburst mode
with strong variations in the jet bulk velocities coupled with strong radio
emission with steeper spectra. We also show that the continuous jets in
microquasars should terminate in strong shocks and possibly inflate radio lobes
similar to extragalactic jet sources. Finally, we investigate the possibility
of testing the predictions of this model with resolved radio observations.

</DOC>
<DOC>
<DOCNO> 84856 </DOCNO>
Crust-core coupling and r-mode damping in neutron stars: a toy model


  R-modes in neutron stars with crusts are damped by viscous friction at the
crust-core boundary. The magnitude of this damping, evaluated by Bildsten and
Ushomirsky (BU) under the assumption of a perfectly rigid crust, sets the
maximum spin frequency for a neutron star spun up by accretion in a Low-Mass
X-ray binary (LMXB). In this paper we explore the mechanical coupling between
the core r-modes and the elastic crust, using a toy model of a constant density
neutron star with a constant shear modulus crust. We find that, at spin
frequencies in excess of ~50 Hz, the r-modes strongly penetrate the crust. This
reduces the relative motion (slippage) between the crust and the core compared
to the rigid crust limit. We therefore revise down, by as much as a factor of
10^2-10^3, the damping rate computed by BU, significantly reducing the maximal
possible spin frequency of neutron star with a solid crust. The dependence of
the crust-core slippage on the spin frequency is complicated, and is very
sensitive to the physical thickness of the crust. If the crust is sufficiently
thick, the curve of the critical spin frequency for the onset of the r-mode
instability becomes multi-valued for some temperatures; this is related to the
avoided crossings between the r-mode and the higher-order torsional modes in
the crust. The critical frequencies are comparable to the observed spins of
neutron stars in LMXBs and millisecond pulsars.

</DOC>
<DOC>
<DOCNO> 14087 </DOCNO>
Cooling gases with Levy flights: using the generalized central limit


  In the last ten years, the generalized central limit theorem established by
Paul Levy in the thirties has been found more and more relevant in physics.
Physicists call 'Levy flights' random walks for which the probability density
of the jump lenghts $x$ decays as $1/x^{1+\alpha}$ with $\alpha<2$ for large
$x$. We give here a glimpse of Levy flights in physics through two examples,
without going into technical details. We first introduce a simple toy model,
the Arrhenius cascade. We then present an important physical process, subrecoil
laser cooling of atomic gases, in which Levy flights play an essential role.

</DOC>
<DOC>
<DOCNO> 10764 </DOCNO>
Zero-point fluctuations in the ground state of a mesoscopic normal ring


  We investigate the persistent current of a ring with an in-line quantum dot
capacitively coupled to an external circuit. Of special interest is the
magnitude of the persistent current as a function of the external impedance in
the zero temperature limit when the only fluctuations in the external circuit
are zero-point fluctuations. These are time-dependent fluctuations which
polarize the ring-dot structure and we discuss in detail the contribution of
displacement currents to the persistent current. We have earlier discussed an
exact solution for the persistent current and its fluctuations based on a Bethe
ansatz. In this work, we emphasize a physically more intuitive approach using a
Langevin description of the external circuit. This approach is limited to weak
coupling between the ring and the external circuit. We show that the zero
temperature persistent current obtained in this approach is consistent with the
persistent current calculated from a Bethe ansatz solution. In the absence of
coupling our system is a two level system consisting of the ground state and
the first excited state. In the presence of coupling we investigate the
projection of the actual state on the ground state and the first exited state
of the decoupled ring. With each of these projections we can associate a phase
diffusion time. In the zero temperature limit we find that the phase diffusion
time of the excited state projection saturates, whereas the phase diffusion
time of the ground state projection diverges.

</DOC>
<DOC>
<DOCNO> 170686 </DOCNO>
Generalizing the Heisenberg Uncertainty Relation


  The proof of the Heisenberg uncertainty relation is modified to produce two
improvements: (a) the resulting inequality is stronger because it includes the
covariance between the two observables, and (b) the proof lifts certain
restrictions on the state to which the relation is applied, increasing its
generality. The restrictions necessary for the standard inequality to apply are
not widely known, and they are discussed in detail. The classical analog of the
Heisenberg relation is also derived, and the two are compared. Finally, the
modified relation is used to address the apparent paradox that eigenfunctions
of the $z$ component of angular momentum $L_z$ do not satisfy the $\phi-L_z$
Heisenberg relation; the resolution is that the restrictions mentioned above
make the usual inequality inapplicable to these states. The modified relation
does apply, however, and it is shown to be consistent with explicit
calculations.

</DOC>
<DOC>
<DOCNO> 174452 </DOCNO>
Beam Energy Evolution of HBT Systematics at the AGS


  We present preliminary results of the first pion interferometry (HBT)
excitation function at intermediate AGS energies. The beam energy evolution of
the correlations' dependence on mT, centrality, and emission angle with respect
to the reaction plane are discussed. Comparisons with predictions of the RQMD
cascade model are made.

</DOC>
<DOC>
<DOCNO> 116547 </DOCNO>
Wavelet entropy as a measure of solar cycle complexity


  Using wavelet analysis approach, we can derive a measure of the disorder
content of solar activity, following the temporal evolution of the so-called
wavelet entropy. The interesting feature of this parameter is its ability to
extract a dynamical complexity information, in terms of frequency distribution
of the energy content, avoiding restrictions, common in the nonlinear dynamics
theory, such as stationarity. The analysis is performed on the monthly time
series of sunspot numbers. From the time behaviour of the wavelet entropy we
found a clear increase in the disorder content of solar activity for the
current 23th solar cycle. This result suggests general low accuracies for
current solar cycleprediction methods. Moreover, we pointed out a possible
connection between wavelet entropy behaviour and solar excursion phases of
solar dipole.

</DOC>
<DOC>
<DOCNO> 120593 </DOCNO>
Molecular hydrogen emission in Cygnus A


  We present J, H and K-band spectroscopy of Cygnus A, spanning 1.0-2.4 micron
in the rest-frame and hence several rovibrational H2, H recombination and
[FeII] emission lines. The lines are spatially extended by up to 6kpc from the
nucleus, but their distinct kinematics indicate that the three groups (H, H2
and [FeII]) are not wholly produced in the same gas. The broadest line,
[FeII]1.644, exhibits a non-gaussian profile with a broad base (FWHM=1040
km/s), perhaps due to interaction with the radio source. Extinctions to the
line-emitting regions substantially exceed earlier measurements based on
optical H recombination lines.
  Hard X-rays from the quasar nucleus are likely to dominate the excitation of
the H2 emission. The results of Maloney, Hollenbach and Tielens (1996) are thus
used to infer the total mass of gas in H2 v=1-0 S(1)-emitting clouds as a
function of radius, for gas densities of 10^3 and 10^5 cm^-3, and stopping
column densities N_H=10^22-10^24 cm^-2. Assuming azimuthal symmetry, at least
2.3E8 Msun of such material is present within 5kpc of the nucleus, if the
line-emitting clouds see an unobscured quasar spectrum. Alternatively, if the
bulk of the X-ray absorption to the nucleus inferred by Ueno et al. (1994)
arises in a circumnuclear torus, the implied gas mass rises to 10^10 Msun. The
latter plausibly accounts for 10^9 yr of mass deposition from the cluster
cooling flow, for which Mdot \simeq 10 Msun/yr within this radius.

</DOC>
<DOC>
<DOCNO> 121487 </DOCNO>
3D simulations of shear instabilities in magnetized flows


  We present results of three-dimensional (3D) simulations of the
magnetohydrodynamic Kelvin-Helmholtz instability in a stratified shear layer.
The magnetic field is taken to be uniform and parallel to the shear flow. We
describe the evolution of the fluid flow and the magnetic field for a range of
initial conditions. In particular, we investigate how the mixing rate of the
fluid depends on the Richardson number and the magnetic field strength. It was
found that the magnetic field can enhance as well as suppress mixing. Moreover,
we have performed two-dimensional (2D) simulations and discuss some interesting
differences between the 2D and 3D results.

</DOC>
<DOC>
<DOCNO> 40645 </DOCNO>
Diffractive Jet Production in Deep-Inelastic e^+p Collisions at HERA


  A measurement is presented of dijet and 3-jet cross sections in low-|t|
diffractive deep-inelastic scattering interactions of the type ep -> eXY, where
the system X is separated by a large rapidity gap from a low-mass baryonic
system Y. Data taken with the H1 detector at HERA, corresponding to an
integrated luminosity of 18.0 pb^(-1), are used to measure hadron level single
and double differential cross sections for 4<Q^2<80 GeV^2, x_pom<0.05 and
p_(T,jet)>4 GeV. The energy flow not attributed to jets is also investigated.
The measurements are consistent with a factorising diffractive exchange with
trajectory intercept close to 1.2 and tightly constrain the dominating
diffractive gluon distribution. Viewed in terms of the diffractive scattering
of partonic fluctuations of the photon, the data require the dominance of
qqbarg over qqbar states. Soft colour neutralisation models in their present
form cannot simultaneously reproduce the shapes and the normalisations of the
differential cross sections. Models based on 2-gluon exchange are able to
reproduce the shapes of the cross sections at low x_pom values.

</DOC>
<DOC>
<DOCNO> 80616 </DOCNO>
The masses of the mesons and baryons. Part II. The Standing Wave Model


  In order to explain the empirical integer multiple rule for the stable mesons
and baryons presented in the preceding paper we assume that the particles are
held together in a cubic nuclear lattice. This is a novel approach to the
particles, based on the fact that the range of the weak nuclear force is only a
thousandth of the diameter of the nucleon, and that the crystals are the
best-known macroscopic bodies held together by a microscopic force. We
investigate the standing waves in a cubic nuclear lattice. From the frequency
distribution of the waves follows that the masses of the $\gamma$-branch
particles are integer multiples of $m(\pi^0)$. We show that each particle has
automatically an antiparticle. Assuming that the energy of the oscillations is
determined by Planck's formula for the energy of a linear oscillator, it turns
out that the $\pi^0$ meson and the other members of the $\gamma$-branch are
like cubic black bodies filled with plane, standing electromagnetic waves. Our
standing wave model explains the integer multiple rule of the masses of the
neutral mesons and baryons of the $\gamma$-branch and uses nothing else but
photons. Our results justify the cubic lattice assumption.

</DOC>
<DOC>
<DOCNO> 70929 </DOCNO>
Massive sterile neutrinos as warm Dark Matter


  We show that massive sterile neutrinos mixed with the ordinary ones may be
produced in the early universe in the right amount to be natural warm dark
matter particles. Their mass should be below 40 keV and the corresponding
mixing angles sin^2 2\theta > 10^{-11} for mixing with \nu_\mu or \nu_\tau,
while mixing with \nu_e is slightly stronger bounded with mass less than 30
keV.

</DOC>
<DOC>
<DOCNO> 122823 </DOCNO>
Analytical Studies on the Structure and Emission of the SS433 Jets


  We study the structure and emission of the SS 433 jets in the X-ray emitting
region and in the inner and hotter portion inside the X-ray emitting region. In
order to consider the jet structure from the inner to outer regions we develop
the hybrid model combining the conical beam and the model beam whose cross
section grows with the distance more slowly. We find that the jet beams in the
inner and hotter portion are of two-temperature and emit a large amount of high
energy gamma photons. Our analyses suggest the thick absorbing envelope to
exist in the SS 433 system. Based on our results, we discuss the possible
acceleration mechanism for the SS 433 jets.

</DOC>
<DOC>
<DOCNO> 119686 </DOCNO>
A Structural and Dynamical Study of Late-Type, Edge-On Galaxies: I.


  We present optical (B & R) and infrared (K_s) images and photometry for a
sample of 49 extremely late-type, edge-on disk galaxies selected from the Flat
Galaxy Catalog of Karenchentsev et al. (1993). Our sample was selected to
include galaxies with particularly large axial ratios, increading the
likelihood that the galaxies in the sample are truly edge-on. We have also
concentrated the sample on galaxies with low apparent surface brightness, in
order to increase the representation of intrinisically low surface brightness
galaxies. Finally, the sample was chosen to have no apprarent bulges or optical
warps so that the galaxies represent undisturbed, ``pure disk'' systems. The
resulting sample forms the basis for a much larger spectroscopic study designed
to place constraints on the physical quantities and processes which shape disk
galaxies. The imaging data presented in this paper has been painstakingly
reduced and calibrated to allow accurate surface photometry of features as
faint as 30 mag/sqr-arcsec in B and 29 mag/sqr-arcsec in R on scales larger
than 10 arcsec. Due to limitations in sky subtraction and flat fielding, the
infrared data can reach only to 22.5 mag/sqr-arcsec in K_s on comparable
scales. As part of this work, we have developed a new method for quantifying
the reliability of surface photometry, which provides useful diagnostics for
the presence of scattered light, optical emission from infrared cirrus, and
other sources of non-uniform sky backgrounds.

</DOC>
<DOC>
<DOCNO> 101002 </DOCNO>
On Descents in Standard Young Tableaux


  In this paper, explicit formulae for the expectation and the variance of
descent functions on random standard Young tableaux are presented. Using these,
it is shown that the normalized variance, $V/E^2$, is bounded if and only if a
certain inequality relating tableau shape to the descent function holds.

</DOC>
<DOC>
<DOCNO> 10033 </DOCNO>
Theory of the Fano Resonance in the STM Tunneling Density of States due


  The conduction electron density of states nearby single magnetic impurities,
as measured recently by scanning tunneling microscopy (STM), is calculated,
taking into account tunneling into conduction electron states only. The Kondo
effect induces a narrow Fano resonance in the conduction electron density of
states, while scattering off the d-level generates a weakly energy dependent
Friedel oscillation. The line shape varies with the distance between STM tip
and impurity, in qualitative agreement with experiments, but is very sensitive
to details of the band structure. For a Co impurity the experimentally observed
width and shift of the Kondo resonance are in accordance with those obtained
from a combination of band structure and strongly correlated calculations.

</DOC>
<DOC>
<DOCNO> 100134 </DOCNO>
Polynomial invariants for torus knots and topological strings


  We make a precision test of a recently proposed conjecture relating
Chern-Simons gauge theory to topological string theory on the resolution of the
conifold. First, we develop a systematic procedure to extract string amplitudes
from vacuum expectation values (vevs) of Wilson loops in Chern-Simons gauge
theory, and then we evaluate these vevs in arbitrary irreducible
representations of SU(N) for torus knots. We find complete agreement with the
predictions derived from the target space interpretation of the string
amplitudes. We also show that the structure of the free energy of topological
open string theory gives further constraints on the Chern-Simons vevs. Our work
provides strong evidence towards an interpretation of knot polynomial
invariants as generating functions associated to enumerative problems.

</DOC>
<DOC>
<DOCNO> 117743 </DOCNO>
Theoretical Implications of Diffuse Non-Thermal Emission from Clusters


  A short review on theoretical implications of non-thermal emission (radio,
extreme ultraviolet, high energy X-ray) from the intra-cluster medium is given.
The origin of cluster radio halos and cluster radio relics is discussed within
the framework of a network of processes producing a non-thermal electron
population. Emphasis is given to the role of old, remnant, presently invisible
relativistic plasma released by former radio galaxies.

</DOC>
<DOC>
<DOCNO> 40231 </DOCNO>
Octet Baryon Charge Radii, Chiral Symmetry and Decuplet Intermediate


  We compute the octet baryon charge radii to O(1/Heavy^3) in heavy baryon
chiral perturbation theory. We examine the effect of including the decuplet of
spin-3/2 baryons explicitly. We find that it does no t improve the level of
agreement between the HBchiPT and experimental values for the Sigma^- charge
radius.

</DOC>
<DOC>
<DOCNO> 8744 </DOCNO>
Resummation of Feynman Diagrams and the Inversion of Matrices


  In many field theoretical models one has to resum two- and four-legged
subdiagrams in order to determine their behaviour. In this article we present a
novel formalism which does this in a nice way. It is based on the central limit
theorem of probability and an inversion formula for matrices which is obtained
by repeated application of the Feshbach projection method. We discuss
applications to the Anderson model, to the many-electron system and to the
phi^4-model. In particular, for the many-electron system with attractive
delta-interaction, we find that the existence of a BCS gap and a macroscopic
value of the Hubbard-Stratonovich field for zero momentum enforce each other.

</DOC>
<DOC>
<DOCNO> 119489 </DOCNO>
Narrow-Line Seyfert 1s: 15 Years Later


  The spectroscopic properties of the objects that came to be called
Narrow-Line Seyfert 1s were first systematically described and named as such 15
years ago by Osterbrock & Pogge (1985). At the time, they were a relatively
rare and peculiar subclass of Seyfert galaxies. Their discovery in large
numbers in X-ray surveys, however, has elevated them to a role as important
members of the AGN family, ones which may hold many keys to understanding the
physics of AGN across the electromagnetic spectrum. This contribution reviews
the spectral classification of the narrow-line Seyfert 1s, and describes some
of the properties that make this unusual class of objects interesting.

</DOC>
<DOC>
<DOCNO> 120379 </DOCNO>
Stellar Populations in the Host Galaxies of Mrk 1014, IRAS 07598+6508,


  We present deep spectroscopic and imaging data of the host galaxies of Mrk
1014, IRAS 07598+6508, and Mrk 231. These objects form part of both the QSO and
the ultraluminous infrared galaxy (ULIG) families, and may represent a
transition stage in an evolutionary scenario. Our imaging shows that all three
objects have highly perturbed hosts with tidal tails and destroyed disks, and
appear to be in the final stages of major mergers. The host galaxies of the
three objects have spectra typical of E+A galaxies, showing simultaneously
features from an old and a young stellar component. We model spectra from
different regions of the host galaxies using Bruzual & Charlot spectral
synthesis models using two component models including an old underlying
population and recent superposed starbursts. Our results indicate a strong
connection between interactions and vigorous bursts of star formation in these
objects. We propose that the starburst ages found are indicative of young ages
for the QSO activity. The young starburst ages found are also consistent with
the intermediate position of these objects in the far infrared color-color
diagram. (abridged)

</DOC>
<DOC>
<DOCNO> 116305 </DOCNO>
Fast Quantum Search Algorithms in Protein Sequence Comparison - Quantum


  Quantum search algorithms are considered in the context of protein sequence
comparison in biocomputing. Given a sample protein sequence of length m (i.e m
residues), the problem considered is to find an optimal match in a large
database containing N residues. Initially, Grover's quantum search algorithm is
applied to a simple illustrative case - namely where the database forms a
complete set of states over the 2^m basis states of a m qubit register, and
thus is known to contain the exact sequence of interest. This example
demonstrates explicitly the typical O(sqrt{N}) speedup on the classical O(N)
requirements. An algorithm is then presented for the (more realistic) case
where the database may contain repeat sequences, and may not necessarily
contain an exact match to the sample sequence. In terms of minimizing the
Hamming distance between the sample sequence and the database subsequences the
algorithm finds an optimal alignment, in O(sqrt{N}) steps, by employing an
extension of Grover's algorithm, due to Boyer, Brassard, Hoyer and Tapp for the
case when the number of matches is not a priori known.

</DOC>
<DOC>
<DOCNO> 151268 </DOCNO>
AdS RG-Flow and the Super-Yang-Mills Cascade


  We study the 5 dimensional SUGRA AdS duals of N=4, N=2 and N=1
Super-Yang-Mills theories. To sequentially break the N=4 theory mass terms are
introduced that correspond, via the duality, to scalar VEVs in the SUGRA. We
determine the appropriate scalar potential and study solutions of the equations
of motion that correspond to RG flows in the field theories. Analysis of the
potential at the end of the RG flows distinguishes the flows appropriate to the
field theory expectations. As already identified in the literature, the dual to
the N=2 theory has flows corresponding to the moduli space of the field theory.
When the N=2 theory is broken to N=1 the single flow corresponding to the
singular point on the N=2 moduli space is picked out as the vacuum. As the N=2
breaking mass scale is increased the vacuum deforms smoothly to previously
analysed N=1 flows.

</DOC>
<DOC>
<DOCNO> 12466 </DOCNO>
Fermi-edge singularities in linear and non-linear ultrafast spectroscopy


  We discuss Fermi-edge singularity effects on the linear and nonlinear
transient response of an electron gas in a doped semiconductor. We use a
bosonization scheme to describe the low energy excitations, which allows to
compute the time and temperature dependence of the response functions. Coherent
control of the energy absorption at resonance is analyzed in the linear regime.
It is shown that a phase-shift appears in the coherent control oscillations,
which is not present in the excitonic case. The nonlinear response is
calculated analytically and used to predict that four wave-mixing experiments
would present a Fermi-edge singularity when the exciting energy is varied. A
new dephasing mechanism is predicted in doped samples that depends linearly on
temperature and is produced by the low-energy bosonic excitations in the
conduction band.

</DOC>
<DOC>
<DOCNO> 70065 </DOCNO>
Longitudinal Resolution in a Large Relativistic Nucleus: Adding a


  We extend the McLerran-Venugopalan model for the gluon distribution functions
of very large nuclei to larger values of the longitudinal momentum fraction xF.
Because gluons with larger values of xF begin to resolve the longitudinal
structure of the nucleus, we find that it is necessary to set up a fully
three-dimensional formalism for performing the calculation. We obtain a
relatively compact expression for the gluon number density provided that the
nucleus is sufficiently large and consists of color-neutral nucleons. Our
expressions for the gluon number density saturate at small transverse momenta.
The nuclear dependence we obtain is such that the number of gluons increases
more slowly than the number of nucleons is increased.

</DOC>
<DOC>
<DOCNO> 122307 </DOCNO>
A Spectral Line Survey from 138.3 to 150.7 GHZ toward Orion-KL


  We present the results of a spectral line survey from 138.3 to 150.7 GHz
toward Orion-KL. The observations were made using the 14 m radio telescope of
Taeduk Radio Astronomy Observatory. Typical system temperatures were between
500 and 700 K, with the sensitivity between $0.02 - 0.06$ K in units of $\rm
T_A^*$.
  A total of 149 line spectra are detected in this survey. Fifty lines have
been previously reported, however we find 99 new detections. Among these new
lines, 32 are `unidentified', while 67 are from molecular transitions with
known identifications. There is no detection of H or He recombination lines.
The identified spectra are from a total of 16 molecular species and their
isotopic variants. In the range from 138.3 to 150.7 GHz, the strongest spectral
line is the J=3-2 transition of CS molecule, followed by transitions of the
$\rm H_2CO$, $\rm CH_3OH$, $\rm CH_3CN$, and $\rm SO_2$. Spectral lines from
the large organic molecules such as $\rm CH_3OH$, $\rm CH_3OCH_3$, $\rm
HCOOCH_3$, $\rm C_2H_5CN$ and $\rm CH_3CN$ are prominent; with 80 % of the
identified lines arising from transitions of these molecules. The rotational
temperatures and column densities are derived using the standard rotation
diagram analysis for $\rm CH_3OH$ ($\rm ^{13}CH_3OH$), $\rm HCOOCH_3$, $\rm
CH_3CN$ and $\rm SO_2$ with $\rm 10\sim 270 K$ and $\rm 0.2\sim 20\times
10^{15} cm^{-2}$. These estimates are fairly comparable to the values for the
same molecule in other frequency regions by other studies.

</DOC>
<DOC>
<DOCNO> 119008 </DOCNO>
Extremely Metal-Poor Stars. VII. The Most Metal-Poor Dwarf, CS 22876-032


  We report high-resolution, high-signal-to-noise, observations of the
extremely metal-poor double-lined spectroscopic binary CS 22876-032. The system
has a long period : P = 424.7 $\pm$ 0.6 days. It comprises two main sequence
stars having effective temperatures 6300 K and 5600 K, with a ratio of
secondary to primary mass of 0.89 $\pm$ 0.04. The metallicity of the system is
[Fe/H] = -3.71 $\pm$ 0.11 $\pm$ 0.12 (random and systematic errors) -- somewhat
higher than previous estimates. We find [Mg/Fe] = 0.50, typical of values of
less extreme halo material. [Si/Fe], [Ca/Fe], and [Ti/Fe], however, all have
significantly lower values, ~ 0.0-0.1, suggesting that the heavier elements
might have been underproduced relative to Mg in the material from which this
object formed. In the context of the hypothesis that the abundance patterns of
extremely metal-poor stars are driven by individual enrichment events and the
models of Woosley and Weaver (1995), the data for CS 22876-032 are consistent
with its having been enriched by a zero-metallicity supernova of mass 30
M$_{\odot}$. As the most metal-poor near-main-sequence-turnoff star currently
known, the primary of the system has the potential to strongly constrain the
primordial lithium abundance. We find A(Li) (= log(N(Li)/N(H)) + 12.00) = 2.03
$\pm$ 0.07, which is consistent with the finding of Ryan et al. (1999) that for
stars of extremely low metallicity A(Li) is a function of [Fe/H].

</DOC>
<DOC>
<DOCNO> 122056 </DOCNO>
The Quest for the Dominant Stellar Population in the Giant Elliptical


  Newly obtained HST/WFPC2 images of the disturbed elliptical galaxy NGC 5018
show that the average amount of internal reddening due to the its complex
``dust web'' is as low as E(B-V)~0.02 within the IUE aperture, thus implying
that its observed and intrinsic energy distributions do not differ
significantly down to UV wavelengths. This, in turn, is quite relevant to the
current debate on the age of its dominant stellar population.

</DOC>
<DOC>
<DOCNO> 118654 </DOCNO>
Detection of H Alpha Emission in a Methane (T-Type) Brown Dwarf


  We report the detection of H{$\alpha$} emission in the T dwarf (methane brown
dwarf) 2MASSW J1237392+652615 over three days using the Keck Low Resolution
Imaging Spectrograph. The measured line flux, log(L$_{H{\alpha}}$/L$_{bol}$) =
$-$4.3, is roughly consistent with early M dwarf activity levels and
inconsistent with decreasing activity trends in late M and L dwarfs. Similar
emission is not seen in two other T dwarfs. We speculate on several mechanisms
that may be responsible for emission, including a strong magnetic field,
continuous flaring, acoustic heat generation, and a close ($a$ $\sim$ 4 - 20
R$_{Jup}$) interacting binary, with the cooler component overflowing its Roche
lobe. We suggest that the M9.5Ve PC 0025+0447 could be a warm analogue to 2MASS
J1237+65, and may be powered by the latter mechanism.

</DOC>
<DOC>
<DOCNO> 12939 </DOCNO>
New type of antiferromagnetic state in stacked nanographite


  Nanographite systems, where graphene sheets of the orders of the nanometer
size are stacked, show novel magnetic properties, such as, spin-glass like
behaviors and the change of ESR line widths in the course of gas adsorptions.
We theoretically investigate stacking effects in the zigzag nanographite sheets
by using a tight binding model with the Hubbard-like onsite interactions. We
find a remarkable difference in the magnetic properties between the simple A-A
and A-B type stackings. For the simple stacking, there are not magnetic
solutions. For the A-B stacking, we find antiferromagnetic solutions for strong
onsite repulsions. The local magnetic moments tend to exist at the edge sites
in each layer due to the large amplitude of wavefunctions at these sites. We
study variations between the A-A and A-B stackings to find that the magnetism
between the two stackings experiences the first order phase transition. The
effect of the interlayer distance is also discussed.

</DOC>
<DOC>
<DOCNO> 12805 </DOCNO>
Vertical Boundary at x ~ 0.11 in the Structural Phase Diagram of the


  The structural phase diagram of the La1-xSrxMnO3 system in the compositional
range 0.08 <= x <= 0.125 has been investigated by high-resolution synchrotron
x-ray powder diffraction techniques between 20-600 K. Recent studies have
reported that there is an unusual rentrant-type phase transition in this range
involving an abrupt change in lattice parameters but no change in the crystal
symmetry, which remains orthorhombic Pbnm. The transition to the reentrant
phase is from a ferromagnetic metallic to a ferromagnetic insulating phase with
some unusual properties. Our results demonstrate that for samples with x
=0.11-0.125 there exist two lower-symmetry structural regions having monoclinic
and triclinic symmetry respectively. There is a sharp first-order transition
from the monoclinic to the triclinic phase coinciding with the transition to
the ferromagnetic insulating phase, and an abrupt crossover from the
orthorhombic Pbnm region with a near-vertical phase boundary just below x =
0.11. The new phases indicate the presence of some novel type of orbital
ordering unlike that found in LaMnO3.

</DOC>
<DOC>
<DOCNO> 69007 </DOCNO>
Localizing Gravity on a String-Like Defect in Six Dimensions


  We present a metric solution in six dimensions where gravity is localized on
a four-dimensional singular string-like defect. The corrections to
four-dimensional gravity from the bulk continuum modes are suppressed by ${\cal
O}(1/r^3)$. No tuning of the bulk cosmological constant to the brane tension is
required in order to cancel the four-dimensional cosmological constant.

</DOC>
<DOC>
<DOCNO> 101856 </DOCNO>
On the algebra A_{\hbar,\eta}(osp(2|2)^{(2)}) and free boson


  A two-parameter quantum deformation of the affine Lie super algebra
$osp(2|2)^{(2)}$ is introduced and studied in some detail. This algebra is the
first example associated with nonsimply-laced and twisted root systems of a
quantum current algebra with the structure of a so-called infinite Hopf family
of (super)algebras. A representation of this algebra at $c=1$ is realized in
the product Fock space of two commuting sets of Heisenberg algebras.

</DOC>
<DOC>
<DOCNO> 116450 </DOCNO>
Vector constants of motion for time-dependent Kepler and isotropic


  A method of obtaining vector constants of motion for time-independent as well
as time-dependent central fields is discussed. Some well-established results
are rederived in this alternative way and new ones obtained.

</DOC>
<DOC>
<DOCNO> 69031 </DOCNO>
Is Nothing Sacred? Vacuum Energy, Supersymmetry and Lorentz Breaking


  Classical superstring vacua have zero vacuum energy and are supersymmetric
and Lorentz-invariant. We argue that all these properties may be destroyed when
quantum aspects of the interactions between particles and non-perturbative
vacuum fluctuations are considered. A toy calculation of string/D-brane
interactions using a world-sheet approach indicates that quantum recoil effects
- reflecting the gravitational back-reaction on space-time foam due to the
propagation of energetic particles - induce non-zero vacuum energy that is
linked to supersymmetry breaking and breaks Lorentz invariance. This model of
space-time foam also suggests the appearance of microscopic event horizons.

</DOC>
<DOC>
<DOCNO> 80611 </DOCNO>
Lattice monopole action in pure SU(3) QCD


  We obtain an almost perfect monopole action numerically after abelian
projection in pure SU(3) lattice QCD. Performing block-spin transformations on
the dual lattice, the action fixed depends only on a physical scale b. Monopole
condensation occurs for large b region. The numerical results show that
two-point monopole interactions are dominant for large b. We next perform the
block-spin transformation analytically in a simplified case of two-point
monopole interactions with a Wilson loop on the fine lattice. The perfect
operator evaluating the static quark potential on the coarse b-lattice are
derived. The monopole partition function can be transformed into that of the
string model. The static potential and the string tension are estimated in the
string model framework. The rotational invariance of the static potential is
recovered, but the string tension is a little larger than the physical one.

</DOC>
<DOC>
<DOCNO> 169688 </DOCNO>
Spectroscopic studies in open quantum systems


  The spectroscopic properties of an open quantum system are determined by the
eigenvalues and eigenfunctions of an effective Hamiltonian H consisting of the
Hamiltonian H_0 of the corresponding closed system and a non-Hermitian
correction term W arising from the interaction via the continuum of decay
channels. The eigenvalues E_R of H are complex. They are the poles of the
S-matrix and provide both the energies and widths of the states. We illustrate
the interplay between Re(H) and Im(H) by means of the different interference
phenomena between two neighboured resonance states. Level repulsion along the
real axis appears if the interaction is caused mainly by Re(H) while a
bifurcation of the widths appears if the interaction occurs mainly due to
Im(H). We then calculate the poles of the S-matrix and the corresponding
wavefunctions for a rectangular microwave resonator with a scatter as a
function of the area of the resonator as well as of the degree of opening to a
guide. The calculations are performed by using the method of exterior complex
scaling. Re(W) and Im(W) cause changes in the structure of the wavefunctions
which are permanent, as a rule. At full opening to the lead, short-lived
collective states are formed together with long-lived trapped states. The
wavefunctions of the short-lived states at full opening to the lead are very
different from those at small opening. The resonance picture obtained from the
microwave resonator shows all the characteristic features known from the study
of many-body systems in spite of the absence of two-body forces. The poles of
the S-matrix determine the conductance of the resonator. Effects arising from
the interplay between resonance trapping and level repulsion along the real
axis are not involved in the statistical theory.

</DOC>
<DOC>
<DOCNO> 10979 </DOCNO>
Theoretical calculations of the primary defects induced by pions and


  In the present work, the bulk degradation of SiC in hadron (pion and proton)
fields, in the energy range between 100 MeV and 10 GeV, is characterised
theoretically by means of the concentration of primary defects per unit
fluence. The results are compared to the similar ones corresponding to diamond,
silicon and GaAs.

</DOC>
<DOC>
<DOCNO> 40602 </DOCNO>
Study of ZZ production at LEP at sqrt(s) = 183 - 209 GeV


  A study of Z boson pair production in e+e- annihilation using the OPAL
detector at LEP is reported. The ZZ production cross-section is measured,
limits on anomalous ZZgamma and ZZZ couplings are derived, and constraints on
models of low scale quantum gravity in extra spatial dimensions are set.

</DOC>
<DOC>
<DOCNO> 7788 </DOCNO>
Comment on "Observation of Spin Injection at a Ferromagnet-Semiconductor


  In a recent Letter Hammar et al. claim the observation of injection of a
spin-polarized current in a two-dimensional electron gas (2DEG). This is an
important observation, since, despite considerable effort of several groups,
all attempts to realize spin-injection into a 2DEG using purely electrical
measurements have failed sofar. However, in my opinion the claim made is not
correct, and the observed behaviour can be explained by a combination of a
magneto resistance (Hall) effect (e.g. generated by the fringe magnetic fields
present at the edges of the ferromagnetic electrode), with a {\it
spin-independent} rectification effect due to the presence of a metal-
semiconductor junction.

</DOC>
<DOC>
<DOCNO> 101741 </DOCNO>
What is the question that MaxEnt answers? A probabilistic interpretation


  The Boltzmann-Wallis-Jaynes' multiplicity argument is taken up and
elaborated. MaxEnt is proved and demonstrated to be just an asymptotic case of
looking for such a vector of absolute frequencies in a feasible set, which has
maximal probability of being generated by a uniform prior generator/pmf.

</DOC>
<DOC>
<DOCNO> 11909 </DOCNO>
Resonant Processes and Exciton Propagation in a Frozen Gas


  We present numerical simulations of a theory of resonant processes in a
frozen gas of excited atoms interacting via dipole-dipole potentials that vary
as $r^{-3}$, where $r$ is the interatomic separation. The simulations calculate
time-dependent averages of transition amplitudes and transition probabilities
for a single atom in a given state interacting resonantly with a uniformly
distributed random gas of atoms in a different state. The averages are over
spatial configurations of the gas atoms, which are held fixed while the
resonant interaction creates a Frenkel exciton that can travel from atom to
atom. We check that the simulations reproduce previously known exact results
when the exciton is not allowed to propagate [Phys. Rev. A 59, 4358 (1999)].
Further, we develop an approximation for the average transition amplitude that
compares well with the numerical results for a wide range of values of the
system parameters.

</DOC>
<DOC>
<DOCNO> 152158 </DOCNO>
Non-Commutative Quantum Mechanics


  A general non-commutative quantum mechanical system in a central potential
$V=V(r)$ in two dimensions is considered. The spectrum is bounded from below
and for large values of the anticommutative parameter $\theta $, we find an
explicit expression for the eigenvalues. In fact, any quantum mechanical system
with these characteristics is equivalent to a commutative one in such a way
that the interaction $V(r)$ is replaced by $V = V ({\hat H}_{HO}, {\hat L}_z)$,
where ${\hat H}_{HO}$ is the hamiltonian of the two-dimensional harmonic
oscillator and ${\hat L}_z$ is z- component of the angular momentum. For other
finite values of $\theta$ the model can be solved by using perturbation theory.

</DOC>
<DOC>
<DOCNO> 7780 </DOCNO>
Quantum Dynamics in Nanoscale Magnets in Dissipative Environments


  In discrete energy structure of nanoscale magnets, nonadiabatic transitions
at avoided level crossings lead to fundamental processes of dynamics of
magnetizations. The thermal environment causes dissipative effects on these
processes. In this paper we review the features of the nonadiabatic transition
and the influence of the thermal environment. In particular we discuss the
temperature independent stepwise structure of magnetization at very low
temperatures (deceptive nonadiabatic transition), the alternate enhancement of
relaxation in the sequence of resonant tunneling points (parity effects), and
processes caused by combinations of nonadiabatic transitions and disturbance
due to external noises.

</DOC>
<DOC>
<DOCNO> 71307 </DOCNO>
Topological Objects in 5D Maxwell Einstein Supergravity


  In this letter is shown that it is possible to obtain scalar hypersurfaces in
5D N=2 SUGRA where the allowed regions with positive definite scalar metric
have a non-trivial topology. This situation may aid in the construction of
domain wall solutions which confine gravity to 4 dimensions.

</DOC>
<DOC>
<DOCNO> 117813 </DOCNO>
The Near-Ultraviolet Continuum of Late-Type Stars


  Analyses of the near-ultraviolet continuum of late-type stars have led to
controversial results regarding the performance of state-of-the-art model
atmospheres. The release of the homogeneous IUE final archive and the
availability of the high-accuracy Hipparcos parallaxes provide an opportunity
to revisit this issue, as accurate stellar distances make it possible to
compare observed absolute fluxes with the predictions of model atmospheres.
  The near-UV continuum is highly sensitive to Teff and [Fe/H], and once the
gravity is constrained from the parallax, these parameters may be derived from
the analysis of low-dispersion "long-wavelength" (2000-3000 A) IUE spectra for
stars previously studied by Alonso et al. (1996; A&AS 117, 227) using the
Infrared Flux Method (IRFM). A second comparison is carried out against the
stars spectroscopically investigated by Gratton et al. (1996; A&A 314, 191). It
is shown that there is a good agreement between Teffs obtained from the IRFM
and from the near-UV continuum, and a remarkable correspondence between
observed and synthetic fluxes for stars with 4000 <= Teff <= 6000 K of any
metallicity and gravity. These facts suggest that model atmospheres provide an
adequate description of the near-UV continuum forming region and that the
opacities involved are essentially understood. For cooler stars, the results of
the IRFM are no longer reliable, as shown by Alonso et al., but the discrepancy
noticed for stars hotter than 6000 K may reflect problems in the model
atmospheres and/or the opacities at these higher temperatures.

</DOC>
<DOC>
<DOCNO> 121928 </DOCNO>
Upper Limits On Periodic, Pulsed Radio Emission from the X-Ray Point


  The Chandra X-ray Observatory recently discovered an X-ray point source near
the center of Cassiopeia A, the youngest known Galactic supernova remnant. We
have conducted a sensitive search for radio pulsations from this source with
the Very Large Array, taking advantage of the high angular resolution of the
array to resolve out the emission from the remnant itself. No convincing
signatures of a dispersed, periodic source or of isolated dispersed pulses were
found, whether for an isolated or a binary source. We derive upper limits of 30
and 1.3 mJy at 327 and 1435 MHz for the phase-averaged pulsed flux density from
this source. The corresponding luminosity limits are lower than those for any
pulsar with age less than 10^4 years. The sensitivities of our search to single
pulses were 25 and 1.0 Jy at 327 and 1435 MHz. For comparison, the Crab pulsar
emits roughly 80 pulses per minute with flux densities greater than 100 Jy at
327 MHz and 8 pulses per minute with flux densities greater than 50 Jy at 1435
MHz. These limits are consistent with the suggestion that the X-ray point
source in Cas A adds to the growing number of neutron stars which are not radio
pulsars.

</DOC>
<DOC>
<DOCNO> 69760 </DOCNO>
Proton spin structure and the low-energy pp -> pp eta' reaction


  Gluonic degrees of freedom induce a contact term in the effective chiral
Lagrangian description of the low-energy pp -> pp eta' reaction. The strength
of this contact term is, in part, related to the amount of spin carried by
polarised gluons in a polarised proton.

</DOC>
<DOC>
<DOCNO> 169781 </DOCNO>
Information transfer and fidelity in quantum copiers


  We find that very different quantum copying machines are optimal depending on
the indicator used to assess their performance. Several quantum copying machine
models acting on non-orthogonal input states are investigated, and assessed
according to two types of criteria: Transfer of (Shannon) information encoded
in the initial states to the copies, and fidelity between the copies and the
initial states. Transformations which optimise information transfer for
messages encoded in qubits are found. If the message is decoded one symbol
at-a-time, information is best copied by a Wootters-Zurek copier.

</DOC>
<DOC>
<DOCNO> 150532 </DOCNO>
Evidence for Winding States in Noncommutative Quantum Field Theory


  We study noncommutative field theories at finite temperature to learn more
about the degrees of freedom in the non-planar sector of these systems. We find
evidence for winding states. At temperatures for which the thermal wavelength
is smaller than the noncommutativity scale, there is a drastic reduction of the
degrees of freedom in the non-planar sector. In this regime, the non-planar
sector has thermodynamics resembling that of a 1+1 dimensional field theory.

</DOC>
<DOC>
<DOCNO> 69161 </DOCNO>
Bosonization of the pairing Hamiltonian


  The problem of the pairing interaction is dealt with even Grassmann variables
in the hamiltonian framework. Eigenfunctions of given energy, seniority and
zero third component of angular momentum are given in terms of single particle
and collective bosonic fields.

</DOC>
<DOC>
<DOCNO> 152630 </DOCNO>
On gravitational interaction of spin 3/2 Nambu-Goldstone fermion


  A new gravitational interaction of spin 3/2 Nambu-Goldstone(N-G) fermion is
constructed, which gives a new framework for the consistent gravitational
coupling of spin 3/2 massless field. The action is invariant under a new global
supersymmetry.

</DOC>
<DOC>
<DOCNO> 119068 </DOCNO>
Simulated Submillimetre Galaxy Surveys


  Current submillimetre surveys are hindered in their ability to reveal
detailed information on the epoch of galaxy formation and the evolutionary
history of a high-redshift starburst galaxy population. The difficulties are
due to the small primary apertures (D < 15 m) of existing submillimetre
telescopes and the limited sensitivities of their first generation of bolometer
cameras. This situation is changing rapidly due to a variety of powerful new
ground-based, airborne and satellite FIR to millimetre wavelength facilities.
Improving our understanding of the luminosity and clustering evolution provides
the motivation for conducting cosmological submillimetre and millimetre
surveys. It is therefore important that we quantify the limitations of the
future surveys and the significance of the results that can be drawn from them.
In this paper we present simulated surveys which are made as realistic as
possible in order to address some key issues confronting existing and
forthcoming surveys. We discuss the results from simulations with a range of
wavelengths (200 um - 1.1 mm), spatial resolutions (6 arcsec - 27 arcsec) and
flux densities (0.01-310 mJy). We address how the measured source-counts could
be affected by resolution and confusion, by the survey sensitivity and noise,
and by the sampling variance due to clustering and shot-noise.

</DOC>
<DOC>
<DOCNO> 40617 </DOCNO>
Multijet Final States in e+e- Annihilation


  We review the current status of analyses of multijet final states in e+e-
annihilation. Results for jet observables from LEP 1, LEP 2 and from the
reanalysis of the PETRA experiment JADE will be presented. A determination of
the b-quark mass using jet observables will be discussed and tests of power
correction models will be shown. Finally determinations of the QCD colour
factors from an analysis of event shape distributions at several energy points
using power corrections will be discussed.

</DOC>
<DOC>
<DOCNO> 118732 </DOCNO>
Mode detection from line-profile variations in Delta Scuti stars


  The phenomenology associated with line profile variations in delta Scuti
stars is reviewed. The three main techniques adopted to detect pulsation modes,
i.e., the pixel-by-pixel analysis, the analysis of the moment time series and
the Fourier Doppler Imaging are presented and discussed. Their application to
the observational data has allowed the reliable detection of several pulsation
modes, many of them not detectable with photometric observations. The need of
better coordination of simultaneous spectroscopic and photometric campaigns in
order to get the complete pulsation spectra of these stars is pointed out. The
observation in different campaigns of the same objects has proved that dramatic
changes in the mode amplitudes are quite common, even in a couple of years (and
maybe less). In the last part of the paper a recent approach to the mode
detection by direct fit of line profile variations in multiperiodic pulsators
is described.

</DOC>
<DOC>
<DOCNO> 40140 </DOCNO>
A frequentist analysis of solar neutrino data


  We calculate with Monte Carlo the goodness of fit and the confidence level of
the standard allowed regions for the neutrino oscillation parameters obtained
from the fit of solar neutrino data. We show that the values of the goodness of
fit and of the confidence level of the allowed regions are significantly
smaller than the standard ones. Using Neyman's method, we also calculate exact
allowed regions with correct frequentist coverage. We show that the standard
allowed region around the global minimum of the least-squares function is a
reasonable approximation of the exact one, whereas the size of the other
regions is dramatically underestimated in the standard method.

</DOC>
<DOC>
<DOCNO> 99899 </DOCNO>
Poincare polynomials of hyperquot schemes


  Hyperquot schemes are generalizations of Grothendieck's Quot scheme to
partial flags. Using a Bialynicki-Birula decomposition, we obtain combinatorial
data for the Betti numbers, and collect this information into the form of
rational generating functions for the Poincare polynomials.

</DOC>
<DOC>
<DOCNO> 102504 </DOCNO>
K-theory computations for boundary algebras of $\tA_2$ groups


  This is an appendix to the paper {\bf Asymptotic K-theory for groups acting
on $\tA_2$ buildings}, and contains the results of the computations performed
by the authors.

</DOC>
<DOC>
<DOCNO> 84398 </DOCNO>
The geometry of the Barbour-Bertotti theories II. The three body problem


  We present a geometric approach to the three-body problem in the
non-relativistic context of the Barbour-Bertotti theories. The Riemannian
metric characterizing the dynamics is analyzed in detail in terms of the
relative separations. Consequences of a conformal symmetry are exploited and
the sectional curvatures of geometrically preferred surfaces are computed. The
geodesic motions are integrated. Line configurations, which lead to curvature
singularities for $N\neq 3$, are investigated. None of the independent scalars
formed from the metric and curvature tensor diverges there.

</DOC>
<DOC>
<DOCNO> 174616 </DOCNO>
Kaon and Pion Ratio Probes of Jet Quenching in Nuclear Collisions


  Non-abelian energy loss in quark gluon plasmas is shown to lead to novel
hadron ratio suppression patterns in ultrarelativistic nuclear collisions. We
apply recent (GLV) estimates for the gluon radiative energy loss, \Delta E(E,R)
\sim E*(R/6 fm)^2, that increases linearly with the jet energy up to E < 20 GeV
and depends quadratically on the nuclear radius, R. The K^-/K^+ and K^+/\pi^+
ratios are found to be most sensitive to the initial density of the plasma.

</DOC>
<DOC>
<DOCNO> 11477 </DOCNO>
Thermodynamical properties of stellar matter: II. Internal energy,


  Starting from the Helmholtz free energy we calculate analytically first- and
second-order derivatives, as internal energy and specific heats, for the ideal
system and the exchange and correlation interactions covering a broad range of
degeneracy and relativity. The complex physics of Coulomb interactions is
expressed by Pade Approximants, which reflect the actual state of our knowledge
with high accuracy. We assume complete ionization and provide a base system of
thermodynamical functions from which any other thermodynamical quantities can
be calculated. We chose for the base system the free energy, the pressure, the
internal energy, the isothermal compressibility (or density exponent), the
coefficient of strain (or temperature exponent), and the isochoric specific
heat. By means of the latter potentials entropy, isobaric specific heat and
adiabatic temperature gradient can be determined. We give comparisons with
quantities which are composed by numerical second-order derivatives of the free
energy and show that numerical derivatives of the free energy as calculated,
for instance, from EOS tables, may produce discontinuities for astrophysically
relevant quantities as, e.g., the adiabatic temperature gradient. Adiabatic
temperature gradients are shown for different chemical compositions (hydrogen,
helium, carbon). Finally the used formalism of Pade Approximants allows
immediate incorporation of recent results from many particle statistics.

</DOC>
<DOC>
<DOCNO> 169605 </DOCNO>
An Epistemological Derivation of Quantum Logic


  This paper deals with the foundations of quantum mechanics. We start by
outlining the characterisation, due to Birkhoff and Von Neumann, of the logical
structures of the theories of classical physics and quantum mechanics, as
boolean and modular lattices respectively. We then derive these descriptions
from what we claim are basic properties of any physical theory - i.e. the
notion that a quantity in such a theory may be analysed into parts and that the
results of this analysis may be treated in languages with an underlying boolean
structure. We shall see that in the course of constructing a model of a theory
with these properties different indistinguishable possibilities will arise for
how the elements of the model may be named, that is to say different
possibilities arise for how they can be associated with points from Set. Taking
a particular collection of possibilities gives the usual boolean lattice of the
propositions of classical physics. Taking all possibilities - in a sense, the
set of all things that may be described by physical theories - gives the
lattice of quantum mechanical propositions. This gives an interpretation of
quantum mechanics as the complete set of such possible descriptions, the
complete physical description of the world.

</DOC>
<DOC>
<DOCNO> 14184 </DOCNO>
Brownian Motion of a Massive Binary


  The dynamical friction and diffusion coefficients are derived for a massive
binary that moves against a uniform background of stars. The random impulses
exerted on the binary's center of mass by the field stars are greater than
those exerted on a point particle due to inelastic scattering. The frictional
force acting on the binary is less than that acting on a point particle due to
randomization of the trajectories of field stars that pass near the binary.
Both effects tend to increase the random motion of a binary compared with that
of a point mass. If the maximum effective impact parameter for gravitational
encounters is comparable to the radius of gravitational influence of the
binary, its Brownian velocity can be increased by a modest factor compared with
that of a single particle. This condition is probably fulfilled in the case of
binary supermassive black holes in galactic nuclei.

</DOC>
<DOC>
<DOCNO> 102630 </DOCNO>
Degrees of polarizations on an abelian surface with real multiplication


  Let F be a real quadratic field, and let R be an order in F. Suppose given a
polarized abelian surface (A,\lambda) defined over a number field k with a
symmetric action of R defined over k. This paper considers varying A within the
k-isogeny class of A to reduce the degree of \lambda and the conductor of R. It
is proved, in particular, that there is a k-isogenous principally polarized
abelian surface with an action of the full ring of integers of F when F has
class number 1 and the degree of \lambda and the conductor of R are odd and
coprime.

</DOC>
<DOC>
<DOCNO> 118124 </DOCNO>
A Search for Resonant Structures in the Zodiacal Cloud with COBE DIRBE:


  We searched the COBE DIRBE Sky and Zodi Atlas for a wake of dust trailing
Mars and for Trojan dust near Jupiter's L5 Lagrange point. We compare the DIRBE
images to a model Mars wake based on the empirical model of the Earth's wake as
seen by the DIRBE and place a 3-sigma upper limit on the fractional overdensity
of particles in the Mars wake of 18% of the fractional overdensity trailing the
Earth. We place a 3-sigma upper limit on the effective emitting area of large
(10-100 micron diameter) particles trapped at Jupiter's L5 Lagrange point of 6
x 10^17 cm^2, assuming that these large dust grains are distributed in space
like the Trojan asteroids. We would have detected the Mars wake if the surface
area of dust in the wake scaled simply as the mass of the planet times the
Poynting-Robertson time scale.

</DOC>
<DOC>
<DOCNO> 150492 </DOCNO>
Effective action in general chiral superfield model


  The effective action in general chiral superfield model with arbitrary
k\"{a}hlerian potential $K(\bar{\Phi},\Phi)$ and chiral (holomorphic) potential
$W(\Phi)$ is considered. The one-loop and two-loop contributions to
k\"{a}hlerian effective potential and two-loop (first non-zero) contribution to
chiral effective potential are found for arbitrary form of functions
$K(\bar{\Phi},\Phi)$ and $W(\Phi)$. It is found that despite the theory is
non-renormalizable in general case two-loop contribution to holomorphic
effective potential is always finite.

</DOC>
<DOC>
<DOCNO> 84269 </DOCNO>
Proof of a generalized Geroch conjecture for the hyperbolic Ernst


  We enunciate and prove here a generalization of Geroch's famous conjecture
concerning analytic solutions of the elliptic Ernst equation. Our
generalization is stated for solutions of the hyperbolic Ernst equation that
are not necessarily analytic, although it can be formulated also for solutions
of the elliptic Ernst equation that are nowhere axis-accessible.

</DOC>
<DOC>
<DOCNO> 72255 </DOCNO>
sigma and kappa in Scattering Processes and New pi0 pi0 Phase Shift Data


  The evidences for sigma(600) and kappa(900) observed in our analyses on the
pi pi and K pi scattering phase shift data are described, briefly. The analysis
have been performed by the interfering amplitude method, which satisfies the
unitarity requirement, using physically meaningful parameters. The introduction
of the negative phase shifts (repulsive force) are essential in the analysis.
New data for the pi0 pi0 scattering amplitudes and the I=0 S wave phase shifts
are presented. The data have been obtained in the pi-p charge exchange
reaction, pi- p --> pi0 pi0 n at 9 GeV by the E135 experiment at the KEK PS.
The amplitude analysis are performed. The behavior of the I=0 S wave phase
shifts below KKbar threshold are consistent with those of the pi+ pi-, so
called, standard data and those of the down-flat solution of the
CERN-Cracow-Munich polarization data. The analysis of the pi0 pi0 phase shift
data observes sigma(600) with the B-W parameters, M_sigma =588 +- 12 MeV and
Gamma_sigma =281 +- 25 MeV, which are in good agreement with those in our
analysis on the pi+ pi- data.

</DOC>
<DOC>
<DOCNO> 101952 </DOCNO>
Elliptic inequalities for near-sonic flow


  A priori estimates are derived for a class of weak solutions near a point of
elliptic degeneracy. An application is given to the high-speed potential flow
of an ideal fluid.

</DOC>
<DOC>
<DOCNO> 116473 </DOCNO>
Measurement of Carbon Disulfide Anion Diffusion in a TPC


  A Negative Ion Time Projection Chamber was used to measure the field
dependence of lateral and longitudinal diffusion for CS$_2$ anions drifting in
mixtures of CS$_2$ and Ar at 40 Torr. Ion drift velocities and limits on the
capture distance for electrons as a function of field and gas mixture are also
reported.

</DOC>
<DOC>
<DOCNO> 10905 </DOCNO>
Semiclassical Density Functional Theory: Strutinsky Energy Corrections


  We develop a semiclassical density functional theory in the context of
quantum dots. Coulomb blockade conductance oscillations have been measured in
several experiments using nanostructured quantum dots. The statistical
properties of these oscillations remain puzzling, however, particularly the
statistics of spacings between conductance peaks. To explore the role that
residual interactions may play in the spacing statistics, we consider many-body
systems which include electron-electron interactions through an explicit
density functional. First, we develop an approximate series expansion for
obtaining the ground state using the idea of the Strutinsky shell correction
method. Next, we relate the second-order semiclassical corrections to the
screened Coulomb potential. Finally, we investigate the validity of the
approximation method by numerical calculation of a one-dimensional model
system, and show the relative magnitudes of the successive terms as a function
of particle number.

</DOC>
<DOC>
<DOCNO> 85343 </DOCNO>
Critical Behaviour in a Planar Dynamical Triangulation Model with a


  We consider a canonical ensemble of dynamical triangulations of a
2-dimensional sphere with a hole where the number $N$ of triangles is fixed.
The Gibbs factor is $\exp (-\mu \sum \deg v)$ where $\deg v$ is the degree of
the vertex $v$ in the triangulation $T$. Rigorous proof is presented that the
free energy has one singularity, and the behaviour of the length $m$ of the
boundary undergoes 3 phases: subcritical $m=O(1)$, supercritical (elongated)
with $m$ of order $N$ and critical with $m=O(\sqrt{N})$. In the critical point
the distribution of $m$ strongly depends on whether the boundary is provided
with the coordinate system or not. In the first case $m$ is of order
$\sqrt{N}$, in the second case $m$ can have order $N^{\alpha}$ for any
$0<\alpha <{1/2}$.

</DOC>
<DOC>
<DOCNO> 170031 </DOCNO>
The non-local content of quantum operations


  We show that quantum operations on multi-particle systems have a non-local
content; this mirrors the non-local content of quantum states. We introduce a
general framework for discussing the non-local content of quantum operations,
and give a number of examples. Quantitative relations between quantum actions
and the entanglement and classical communication resources needed to implement
these actions are also described. We also show how entanglement can catalyse
classical communication from a quantum action.

</DOC>
<DOC>
<DOCNO> 10667 </DOCNO>
Exactly solvable toy model for the pseudogap state


  We present an exactly solvable toy model which describes the emergence of a
pseudogap in an electronic system due to a fluctuating off-diagonal order
parameter. In one dimension our model reduces to the fluctuating gap model
(FGM) with a gap Delta (x) that is constrained to be of the form Delta (x) = A
e^{i Q x}, where A and Q are random variables. The FGM was introduced by Lee,
Rice and Anderson [Phys. Rev. Lett. {\bf{31}}, 462 (1973)] to study fluctuation
effects in Peierls chains. We show that their perturbative results for the
average density of states are exact for our toy model if we assume a Lorentzian
probability distribution for Q and ignore amplitude fluctuations. More
generally, choosing the probability distributions of A and Q such that the
average of Delta (x) vanishes and its covariance is < Delta (x) Delta^{*}
(x^{prime}) > = Delta_s^2 exp[ {- | x - x^{\prime} | / \xi}], we study the
combined effect of phase and amplitude fluctutations on the low-energy
properties of Peierls chains. We explicitly calculate the average density of
states, the localization length, the average single-particle Green's function,
and the real part of the average conductivity. In our model phase fluctuations
generate delocalized states at the Fermi energy, which give rise to a finite
Drude peak in the conductivity. We also find that the interplay between phase
and amplitude fluctuations leads to a weak logarithmic singulatity in the
single-particle spectral function at the bare quasi-particle energies. In
higher dimensions our model might be relevant to describe the pseudogap state
in the underdoped cuprate superconductors.

</DOC>
<DOC>
<DOCNO> 151882 </DOCNO>
On Fractional Instanton Numbers in Six Dimensional Heterotic E8 x E8


  We derive the precise relation between level matching condition and
fractional instanton numbers in six dimensional, abelian and supersymmetric
orbifolds of E8 x E8 heterotic string theory. The fractional part of the two E8
instanton numbers is explicitly calculated in terms of the gauge twist. This
relation is then used to show that the classification of these orbifolds can be
given in terms of flat bundles away from the orbifold singularities under the
only constraint that the sum of the fractional parts of the gauge instanton
numbers match the fractional part of the gravitational instanton number locally
at every fixed point. This directly carries over to M-theory on S^1/Z_2

</DOC>
<DOC>
<DOCNO> 121663 </DOCNO>
Constraints on the redshift of reionization from CMB data


  We use the recent CMB power spectrum measurement by the Maxima experiment
(Hanany et al. 2000) to constrain the redshift of reionization z_re. This
becomes possible by combining the CMB data with cosmological parameters from
various independent measurements, including Big Bang Nucleosynthesis (BBN) and
X-ray cluster data. Most notably, our results provide a robust lower bound on
z_re. We find that z_re>15 (8) at the 68% (95%) confidence level, unless the
Hubble constant is larger than 75 km/s/Mpc.

</DOC>
<DOC>
<DOCNO> 101242 </DOCNO>
Structural Characterization of Compoundness


  We recover the rays in the tensor product of Hilbert spaces within a larger
class of so called `states of compoundness', structured as a complete lattice
with the `state of separation' as its top element. At the base of the
construction lies the assumption that the cause of actuality of a property of
one of the (as individual considered) entities in the compound system can be
actuality of a property of the other one.

</DOC>
<DOC>
<DOCNO> 116491 </DOCNO>
Symmetry breaking and coarsening in spatially distributed evolutionary


  Sexual reproduction presents significant challenges to formal treatment of
evolutionary processes. A starting point for systematic treatments of
ecological and evolutionary phenomena has been provided by the gene centered
view of evolution which assigns effective fitness to each allele instead of
each organism. The gene centered view can be formalized as a dynamic mean field
approximation applied to genes in reproduction / selection dynamics. We show
that the gene centered view breaks down for symmetry breaking and pattern
formation within a population; and show that spatial distributions of organisms
with local mating neighborhoods in the presence of disruptive selection give
rise to such symmetry breaking and pattern formation in the genetic composition
of local populations. Global dynamics follows conventional coarsening of
systems with nonconserved order parameters. The results have significant
implications for the ecology of genetic diversity and species formation.

</DOC>
<DOC>
<DOCNO> 170679 </DOCNO>
Loading of a Bose-Einstein condensate in the boson-accumulation regime


  We study the optical loading of a trapped Bose-Einstein condensate by
spontaneous emission of atoms in excited electronic state in the
Boson-Accumulation Regime. We generalize the previous simplified analysis of
ref. [Phys. Rev. A 53, 2466 (1996)], to a 3D case in which more than one trap
level of the excited state trap is considered. By solving the corresponding
quantum many-body master equation, we demonstrate that also for this general
situation the photon reabsorption can help to increase the condensate fraction.
Such effect could be employed to realize a continuous atom laser, and to
overcome condensate losses.

</DOC>
<DOC>
<DOCNO> 119377 </DOCNO>
The hardness-duration correlation in the two classes of gamma-ray bursts


  The well-known hardness-duration correlation of gamma-ray bursts (GRBs) is
investigated with the data of the 4B catalog. We find that, while the hardness
ratio and the duration are obviously correlated for the entire set of the 4B
catalog, they are not at all correlated for the two subsets divided at the
duration of 2 seconds. However, for other subsets with comparable sizes, the
two quantities are significantly correlated. The following conclusions are then
reached: (1) the existence of two classes of GRBs is confirmed; (2) the
hardness ratio and the duration are not at all correlated for any of the two
classes; (3) different classes of GRBs have different distributions of the
hardness ratio and the duration and it is this difference that causes the
correlation between the two quantities for the entire set of the bursts.

</DOC>
<DOC>
<DOCNO> 151176 </DOCNO>
String Junctions in B Field Background


  It has been recently shown that F-theory on K3 with background B fields (NSNS
and RR 2-forms) is dual to the CHL string in 8 dimensions. In this paper, we
reexamine this duality in terms of string junctions in type IIB string theory.
It is in particular stressed that certain 7-brane configurations produce Sp
gauge groups in a novel way.

</DOC>
<DOC>
<DOCNO> 12630 </DOCNO>
Duality and quasiparticles in the Calogero-Sutherland model: Some exact


  The quantum-mechanical many-body system with the potential proportional to
the pairwise inverse-square distance possesses a strong-weak coupling duality.
Based on this duality, particle and/or quasiparticle states are described as
SU(1,1) coherent states. The constructed quasiparticle states are of
hierarchical nature.

</DOC>
<DOC>
<DOCNO> 13224 </DOCNO>
Breakdown of the perturbative renormalization group for S >= 1 random


  We investigate the application of a perturbative renormalization group (RG)
method to random antiferromagnetic Heisenberg chains with arbitrary spin size.
At zero temperature we observe that initial arbitrary probability distributions
develop a singularity at J=0, for all values of spin S. When the RG method is
extended to finite temperatures, without any additional assumptions, we find
anomalous results for S >= 1. These results lead us to conclude that the
perturbative scheme is not adequate to study random chains with S >= 1.
Therefore a random singlet phase in its more restrictive definition is only
assured for spin-1/2 chains.

</DOC>
<DOC>
<DOCNO> 121608 </DOCNO>
Scattering and Polarization Properties of the Non-Spherical Particles


  The albedo and dichroic polarization of spheroidal particles are studied. For
the description of the phase function two asymmetry parameters $g_{||}$ and
$g_{\bot}$ characterizing the anisotropy in forward/backward and left/right
directions are introduced and calculated. The consideration is based on the
solution to the light scattering problem by the Separation of Variables Method
(Voshchinnikov and Farafonov, 1993).

</DOC>
<DOC>
<DOCNO> 170545 </DOCNO>
Realistic teleportation with linear optical elements


  We calculate the highest possible information gain in a measurement of
entangled states when employing a beamsplitter. The result is used to evaluate
the fidelity, averaged over all unknown inputs, in a realistic teleportation
protocol that takes account of the imperfect detection of Bell states. Finally,
we introduce a probabilistic teleportation scheme, where measurements are made
in a partially entangled basis.

</DOC>
<DOC>
<DOCNO> 116241 </DOCNO>
Protein Folding Simulations in a Deformed Energy Landscape


  A modified version of stochastic tunneling, a recently introduced global
optimization technique, is introduced as a new generalized-ensemble technique
and tested for a benchmark peptide, Met-enkephalin. It is demonstrated that the
new technique allows to evaluate folding properties of this peptide

</DOC>
<DOC>
<DOCNO> 9317 </DOCNO>
Magnetic and structural properties of the double-perovskite Ca_2FeReO_6


  We suceeded in the preparation of polycrystalline Ca_2FeReO_6 which has a
Curie temperature of 540 K, the highest value of all magnetic perovskites
investigated up to now. This material has been characterised by X-ray and
neutron powder diffraction. We found at 548 K a monoclinic unit cell (space
group P2_1/n) with a=5.4366(5) A, b=5.5393(5) A, c=7.7344(5) A, and
beta=90.044(4) deg. For low temperatures a phase separation in two monoclinic
phases with identical cell volume is observed in neutron scattering. The two
phases possess different magnetic structure and coercivity. 57-Fe-Moessbauer
spectroscopy measurements show the presence of four different Fe(3+) positions
indicating two different phases at room temperature, indistinguishable in the
diffraction experiments. The conductivity is thermally activated for all
temperatures and no significant magnetoresistivity is observed.

</DOC>
<DOC>
<DOCNO> 117861 </DOCNO>
Observed Properties of Mass Loss in Symbiotic Binaries


  Both the red giants and the Mira variables in symbiotic systems have
systematically higher mass-loss rates than do typical galactic giants and
Miras, which suggests that only very evolved giants, and so those with highest
mass-loss rates, can support symbiotic behaviour in widely separated binary
systems. They often show a flattened mass-loss geometry due to an intrinsically
inhomogeneous mass loss and/or tidal interactions between the binary
components. The main body of a symbiotic nebula is thus formed from material
lost in the giant wind, while the hot component is responsible for its
ionization and excitation. In addition, the fast wind and/or jet ejection from
the hot component, whenever occur, give rise to the complex, often bipolar,
shape of symbiotic nebulae. Observations of resolved nebulae also suggest that
the binary geometry and nebular structure are aligned but the bipolar outflow
may be not orthogonal to the orbital plane in all cases.

</DOC>
<DOC>
<DOCNO> 71106 </DOCNO>
GDH2000 Convenor's Report: Spin Polarizabilities


  The subject of low energy polarized Compton scattering from the proton, which
is characterized by phenomenological spin-polarizabilities, is introduced and
connection is made to new theoretical and experimental developments which were
reported to this meeting.

</DOC>
<DOC>
<DOCNO> 10333 </DOCNO>
The Labusch Parameter of a Driven Flux Line Lattice in


  We have investigated the influence of a driving force on the elastic coupling
(Labusch parameter) of the field-cooled state of the flux line lattice (FLL) in
400 nm thick YBa$_2$Cu$_3$O$_7$ superconducting films. We found that the FLL of
a field-cooled state without driving forces is not in an equilibrium state.
Results obtained for magnetic fields applied at $0^\circ$ and 30$^\circ$
relative to CuO$_2$ planes, show an enhancement of the elastic coupling of the
films at driving current densities several orders of magnitude smaller than the
critical one. Our results indicate that the FLL appears to be in a relatively
ordered, metastable state after field cooling without driving forces.

</DOC>
<DOC>
<DOCNO> 101048 </DOCNO>
L-presentations and branch groups


  We introduce L-presentations: group presentations given by a generating set,
a set of relations and a set of substitution rules on the generating set
producing more relations. We first study in full generality the structure of
finitely L-presented groups, i.e. groups for which all the above sets are
finite, and then show that a broad class of groups acting on rooted trees admit
explicitly constructible finite L-presentations: they are the "branch" groups
defined by R. Grigorchuk.

</DOC>
<DOC>
<DOCNO> 40489 </DOCNO>
Preliminary BABAR results on B0 mixing with dileptons and on lifetime


  With an integrated luminosity of 7.7 fb-1 collected on resonance by BABAR at
the PEP-II asymmetric B Factory, we measure the difference in mass between the
neutral B eigenstates, Delta(m_d), to be (0.507+/-0.015+/-0.022)x 10^{12} hbar
s^{-1} with dileptons events and present preliminary results for the B^0
lifetime, tau(B^0) = 1.55+/-0.05+/-0.07 ps and tau(B^0) = 1.62+/-0.02+/-0.09 ps
obtained from partial reconstruction of the two B^0 decay processes
respectively B^0-->D^{*-}pi^+ and B^0-->D^{*-} l^+ nu_l.

</DOC>
<DOC>
<DOCNO> 80750 </DOCNO>
Chiral properties of domain-wall quarks in quenched QCD


  We investigate the chiral properties of quenched domain-wall QCD (DWQCD) at
the lattice spacings $a^{-1} \simeq 1$ and 2 GeV for both plaquette and
renormalization-group (RG) improved gauge actions. In the case of the plaquette
action we find that the quark mass defined through the axial Ward-Takahashi
identity remains non-vanishing in the DWQCD chiral limit that the bare quark
mass $m_f\to 0$ and the length of the fifth dimension $N_s\to\infty$,
indicating that chiral symmetry is not realized with quenched DWQCD up to
$a^{-1} \simeq 2$ GeV. The behavior is much improved for the RG-improved gauge
action: while a non-vanishing quark mass remains in the chiral limit at
$a^{-1}\simeq 1$ GeV, the result at $a^{-1}\simeq 2$ GeV is consistent with an
exponentially vanishing quark mass in the DWQCD chiral limit, indicating the
realization of exact chiral symmetry. An interpretation and implications are
briefly discussed.

</DOC>
<DOC>
<DOCNO> 120759 </DOCNO>
An X-ray Binary Model for the Galactic Center Source IRS 13E


  We present several models for IRS 13E, an infrared, mm and X-ray source in
the Galactic Center. Our favored interpretation is that of an early-type binary
with strong colliding winds emission. This naturally explains the observed
X-ray count rate and the strong infrared emission lines, and has a distinct
advantage over competing hypotheses based upon a single star or black-hole
system.

</DOC>
<DOC>
<DOCNO> 120757 </DOCNO>
Molecular gas and star formation in BIMA SONG bars


  Using a sample of 7 barred spirals from the BIMA Survey of Nearby Galaxies
(SONG), we compare the molecular gas distribution in the bar, to recent massive
star formation activity. In all 7 galaxies, Halpha is offset azimuthally from
the CO on the downstream side. The maximum offset, at the bar ends, ranges from
170-570 pc, with an average of 320 +/- 120 pc. We discuss whether the observed
offsets are consistent with the description of gas flows in bars provided by
the two main classes of models: n-body models and hydrodynamic models. This
work is supported by NSF grants AST 9981289, AST 9981308.

</DOC>
<DOC>
<DOCNO> 170388 </DOCNO>
Particle on a polygon: Quantum Mechanics


  We study the quantization of a model proposed by Newton to explain
centripetal force namely, that of a particle moving on a regular polygon. The
exact eigenvalues and eigenfunctions are obtained. The quantum mechanics of a
particle moving on a circle and in an infinite potential well are derived as
limiting cases.

</DOC>
<DOC>
<DOCNO> 84958 </DOCNO>
A Low Matter Density Decaying Vacuum Cosmology from Complex Metric


  A low matter density decaying vacuum cosmology is proposed on the assumption
that the universe's radius is a complex quantity \hat{R} if it is regarded as
having a zero energy-momentum tensor. But we find that when the radius is real,
it contains matter. Using the Einstein-Hilbert action principle, the physical
scale factor R(t) =|\hat{R}| is obtained as equal to (R_0^{2} + t^{2})^{1/2}
with R_0 representing the finite radius of the universe at t=0. The resulting
physical picture is roughly a theoretical justification of the old Ozer-Taha
model. The new model is devoid of all cosmological problems. In particular, it
confirms the bounds on H_p, the present value of the Hubble parameter: 0.85 <
H_p t_p < 1.91 and faces no age problem. We argue that the total energy density
consists of parts corresponding to relativistic/non-relativistic matter, a
positive vacuum energy and a form of matter with equation of state p_K = -(1/3)
rho_K (textures or generally K-matter), and the following predictions are made
for the present nonrelativistic era: Omega_{M,n.rel.} \approx 2/3,
Omega_{V,n.rel.} \approx 1/3, Omega_ <<1, Omega_K \approx 1, where a parameter
corresponding to K-matter is taken to be unity. It is shown that the spacetime
with complex metric has signature changing properties. Using quantum
cosmological considerations, it is shown that the wave function is peaked about
the classical contour of evolution and the minimum radius R_0 of the
nonsingular model is predicted as comparable with the Planck length.
  PACS No(s); 98.80 Hw, 04.20, 04.60

</DOC>
<DOC>
<DOCNO> 10808 </DOCNO>
Electronic Processes at the Breakdown of the Quantum Hall Effect


  Microscopic processes giving the energy gain and loss of a two-dimensional
electron system in long-range potential fluctuations are studied theoretically
at the breakdown of the quantum Hall effect in the case of even-integer filling
factors. The Coulomb scattering within a broadened Landau level is proposed to
give the gain, while the phonon scattering to give the loss. The energy balance
equation shows that the electron temperature T_e and the diagonal conductivity
sigma_{xx} exhibit a bistability above the lower critical electric field
E_{c1}. Calculated values of E_{c1} as well as T_e and sigma_{xx} at E_{c1} are
in agreement with the observed values in their orders of magnitude.

</DOC>
<DOC>
<DOCNO> 39939 </DOCNO>
The $\phi(1020)\to\pi^0\pi^0\gamma$ decay


  In the SND experiment at VEPP-2M $e^+e^-$ collider the
$\phi(1020)\to\pi^0\pi^0\gamma$ decay was studied and its branching ratio was
measured: $B(\phi\to\pi^0\pi^0\gamma)=(1.221\pm 0.098\pm0.061)\cdot10^{-4}$. It
was shown, that $f_0(980)\gamma$ intermediate state dominates in this decay and
the $f_0(980)$-meson parameters were obtained.

</DOC>
<DOC>
<DOCNO> 170147 </DOCNO>
Entanglement Swapping Chains for General Pure States


  We consider entanglement swapping schemes with general (rather than
maximally) entangled bipartite states of arbitary dimension shared pairwise
between three or more parties in a chain. The intermediate parties perform
generalised Bell measurements with the result that the two end parties end up
sharing a entangled state which can be converted into maximally entangled
states. We obtain an expression for the average amount of maximal entanglement
concentrated in such a scheme and show that in a certain reasonably broad class
of cases this scheme is provably optimal and that, in these cases, the amount
of entanglement concentrated between the two ends is equal to that which could
be concentrated from the weakest link in the chain.

</DOC>
<DOC>
<DOCNO> 84204 </DOCNO>
Spectral Representation and the Averaging Problem in Cosmology


  We investigate the averaging problem in cosmology as the problem of
introducing a distance between spaces.
  We first introduce the spectral distance, which is a measure of closeness
between spaces defined in terms of the spectra of the Laplacian. Then we define
a space S, the space of all spaces equipped with the spectral distance. We
argue that this space S can be regarded as a metric space and that it also
possess other desirable properties. These facts make the space S a suitable
arena for spacetime physics.
  We apply the spectral framework to the averaging problem:
  We sketch the model-fitting procedure in terms of the spectral
representation, and also discuss briefly how to analyze the dynamical aspects
of the averaging procedure with this scheme.
  In these analyses, we are naturally led to the concept of the apparatus- and
the scale-dependent effective evolution of the universe. These observations
suggest that the spectral scheme seems to be suitable for the quantitative
analysis of the averaging problem in cosmology.

</DOC>
<DOC>
<DOCNO> 120536 </DOCNO>
Shedding light on the dark side of galaxy formation: submillimetre


  Most new sub-mm/mm surveys, both deep and shallow, are being targeted at rich
cluster fields. I explain why, comparing surveys that have exploited weak
lensing by massive foreground clusters with those done in blank fields.

</DOC>
<DOC>
<DOCNO> 151848 </DOCNO>
Phase transition in Wilson loop correlator from AdS/CFT correspondence


  A previous calculation of the phase transition in the Wilson loop correlator
in the zero temperature AdS/CFT correspondence is extended to the case where
the loops are concentric circles of unequal radii. This phase transition occurs
due to the instability of the classical string stretched between the loops. We
compute the string action and its expansion in the distance h between the loops
for small h. We also find that the connected minimal surface is subleading or
does not even exist when h=0 and the radii are considerably different. This
feature has no analogue in flat space.

</DOC>
<DOC>
<DOCNO> 70210 </DOCNO>
Phase Space Description of the Leading Order Quark and Gluon Production


  We derive source terms for the production of quarks and gluons from the QCD
vacuum in the presence of a space-time dependent external chromofield A_{cl} to
the order of S^{(1)}. We found that the source terms for the parton production
processes A_{cl} -> q\bar{q} and A_{cl},A_{cl}A_{cl} -> gg also include the
annihilation processes q\bar{q} -> A_{cl} and gg -> A_{cl},A_{cl}A_{cl}. The
source terms we derive are applicable for the description of the production of
partons with momentum p larger rhan gA which itself must be larger than
\Lambda_{QCD}. We observe that these source terms for the production of partons
from a space-time dependent chromofield can be used to study the production and
equilibration of the quark-gluon plasma during the very early stages of an
ultrarelativistic heavy-ion collision.

</DOC>
<DOC>
<DOCNO> 101086 </DOCNO>
Left ordered groups with no nonabelian free subgroups


  There has been interest recently concerning when a left ordered group is
locally indicable. Bergman and Tararin have shown that not all left ordered
groups are locally indicable, but all known examples contain a nonabelian free
subgroup. We shall show for a large class of groups not containing a nonabelian
free subgroup, that any left ordered group in this class is locally indicable.
Specifically this class is the smallest class of groups containing NS and
Thompson's group of piecewise linear homeomorphisms of the unit interval, and
is closed under taking subgroups, quotient groups, extensions and directed
unions; here NS is the class of groups which do not contain a nonabelian
subsemigroup. We shall also show that certain free products with an amalgamated
cyclic subgroup are left orderable.

</DOC>
<DOC>
<DOCNO> 101618 </DOCNO>
Non-Commutative Calabi-Yau Manifolds


  We discuss aspects of the algebraic geometry of compact non-commutative
Calabi-Yau manifolds. In this setting, it is appropriate to consider local
holomorphic algebras which can be glued together into a compact Calabi-Yau
algebra. We consider two examples: a toroidal orbifold T^6/Z_2 x Z_2, and an
orbifold of the quintic in CP_4, each with discrete torsion. The
non-commutative geometry tools are enough to describe various properties of the
orbifolds. First, one describes correctly the fractionation of branes at
singularities. Secondly, for the first example we show that one can recover
explicitly a large slice of the moduli space of complex structures which deform
the orbifold. For this example we also show that we get the correct counting of
complex structure deformations at the orbifold point by using traces of
non-commutative differential forms (cyclic homology).

</DOC>
<DOC>
<DOCNO> 10278 </DOCNO>
Quasiparticle and Cooper Pair Tunneling in the Vortex State of Bi-2212


  From measurements of the c-axis I-V characteristics of intrinsic Josephson
junctions in Bi_2Sr_2CaCu_2O_{8+delta} (Bi-2212) mesas we obtain the field
dependence (H || c) of the quasiparticle (QP) conductivity, sigma_q(H,T), and
of the Josephson critical current density, J_c(H,T). The quasiparticle
conductivity sigma_q(H) increases sharply with H and reaches a plateau at 0.05
T <H< 0.3 T. We explain such behavior by the dual effect of supercurrents
around vortices. First, they enhance the QP DOS, leading to an increase of
sigma_q with H at low H and, second, they enhance the scattering rate for
specular tunneling as pancakes become disordered along the c-axis at higher H,
leading to a plateau at moderate H.

</DOC>
<DOC>
<DOCNO> 68499 </DOCNO>
Color Superconductivity in High Density Quark Matter


  We review recent progress on the phenomena of color superconductivity in high
density quark matter. We begin with a brief overview of the unique aspects of
physics near a Fermi surface and the implications for renormalization group
(RG) techniques. We next discuss the qualitative differences between asymptotic
densities, where the effective coupling constant can be made arbitrarily small,
and intermediate densities where quark matter is still strongly coupled. It is
in the latter regime where RG techniques are particularly useful, in that they
yield a generic description of possible behaviors without relying on an
expansion in the strong coupling constant. Finally, we discuss aspects of the
QCD groundstate at asymptotic densities, which can be determined in a
systematic weak coupling expansion.

</DOC>
<DOC>
<DOCNO> 102059 </DOCNO>
Geodesics and Spanning Trees for Euclidean First-Passage Percolation


  The metric $D_\alpha (q,q')$ on the set $Q$ of particle locations of a
homogeneous Poisson process on $R^d$, defined as the infimum of $(\sum_i |q_i -
q_{i+1}|^\alpha)^{1/\alpha}$ over sequences in $Q$ starting with $q$ and ending
with $q'$ (where $| . |$ denotes Euclidean distance) has nontrivial geodesics
when $\alpha > 1$. The cases $1 <\alpha < \infty$ are the Euclidean
first-passage percolation (FPP) models introduced earlier by the authors while
the geodesics in the case $\alpha = \infty$ are exactly the paths from the
Euclidean minimal spanning trees/forests of Aldous and Steele. We compare and
contrast results and conjectures for these two situations. New results for $1 <
\alpha < \infty$ (and any $d$) include inequalities on the fluctuation
exponents for the metric ($\chi \le 1/2$) and for the geodesics ($\xi \le 3/4$)
in strong enough versions to yield conclusions not yet obtained for lattice
FPP: almost surely, every semi-infinite geodesic has an asymptotic direction
and every direction has a semi-infinite geodesic (from every $q$). For $d=2$
and $2 le \alpha < \infty$, further results follow concerning spanning trees of
semi-infinite geodesics and related random surfaces.

</DOC>
<DOC>
<DOCNO> 85012 </DOCNO>
Baryonic and Non-Baryonic Dark Matter


  Cosmological nucleosynthesis calculations imply that there should be both
non-baryonic and baryonic dark matter. Recent data suggest that some of the
non-baryonic dark matter must be "hot" (i.e. massive neutrinos) and there may
also be evidence for "cold" dark matter (i.e. WIMPs). If the baryonic dark
matter resides in galactic halos, it is likely to be in the form of compact
objects (i.e. MACHOs) and these would probably be the remnants of a first
generation of pregalactic or protogalactic Population III stars. Many
candidates have been proposed - brown dwarfs, red dwarfs, white dwarfs or black
holes - and at various times each of these has been in vogue. We review the
many types of observations which can be used to constrain or exclude both
baryonic and non-baryonic dark matter candidates.

</DOC>
<DOC>
<DOCNO> 178725 </DOCNO>
Microscopic substructure effects in potential-model descriptions of the


  The spectroscopic factor arises from short-range effects in the nuclear wave
function. On the other hand, cross sections for external capture reactions,
such as $^7$Be$(p,\gamma)^8$B at low energies, depend primarily on the
asymptotic normalization of the bound-state wave function -- a long-range
property. We investigate the relationship between potential models and the full
many-body problem to illustrate how microscopic substructure effects arise
naturally in the relevant transition matrix element and can be (in part)
accounted for by a spectroscopic factor.

</DOC>
<DOC>
<DOCNO> 12206 </DOCNO>
The de Haas - van Alphen effect in two-dimensional metals


  The de Haas - van Alphen effect in two-dimensional (2D) metals is
investigated at different conditions and with different shapes of Landau levels
(LLs). The analytical calculations can be done when many LLs are occupied. We
consider the cases of fixed particle number ($N=const$), fixed chemical
potential ($\mu =const$) and the intermediate situation of finite electron
reservoir. The last case takes place in organic metals due to
quasi-one-dimensional sheets of Fermi surface.
   We obtained the envelopes of magnetization oscillations in all these cases
in the limit of low temperature and Dingle temperature, where the oscillations
can not be approximated by few first terms in the harmonic expansion. The
results are compared and shown to be substantially different for different
shapes of LLs.
  The simple relation between the shape of LLs and the wave form of
magnetization oscillations is found. It allows to obtain the density of states
distribution at arbitrary magnetic field and spin-splitting using the
measurement of the magnetization curve.
  The analytical formula for the magnetization at $\mu =const$ and the
Lorentzian shape of LLs at arbitrary temperature, Dingle temperature and spin
splitting is obtained and used to examine the possibility of the diamagnetic
phase transition in 2D metals.

</DOC>
<DOC>
<DOCNO> 123195 </DOCNO>
MERLIN imaging of the maser flare in Markarian 348


  MERLIN images of Mrk 348 at 22 GHz show water maser emission at 0.02 - 0.11
Jy, within approximately 0.8 pc of the nucleus. This is the first direct
confirmation that molecular material exists close to the Seyfert 2 nucleus. Mrk
348 was observed in 2000 May one month after Falcke et al. (2000) first
identified the maser in single-dish spectra. The peak maser flux density has
increased about threefold. The masing region is < 0.6 pc in radius. The flux
density of radio continuum emission from the core has been rising for about 2
years. The maser-core separation is barely resolved but at the 3 sigma
significance level they are not coincident along the line of sight. The masers
lie in the direction of the northern radio lobes and probably emanate from
material shocked by a jet with velocity close to c. The correlation between the
radio continuum increase and maser flare is explained as arising from high
level nuclear activity through a common excitation mechanism although direct
maser amplification of the core by masers tracing a Keplerian disc is not
completely ruled out.

</DOC>
<DOC>
<DOCNO> 178705 </DOCNO>
Large Nuclear shape transition at finite temperature in a relativistic


  The relativistic Hartree-BCS theory is applied to study the temperature
dependence of nuclear shape and pairing gap for $^{166}Er$ and $^{170}Er$. For
both the nuclei, we find that as temperature increases the pairing gap vanishes
leading to phase transition from superfluid to normal phase as is observed in
nonrelativistic calculation. The deformation evolves from prolate shapes to
spherical shapes at $T\sim 2.7$ MeV. Comparison of our results for heat
capacity with the ones obtained in the non-relativistic mean field framework
indicates that in the relativistic mean field theory the shape transition
occurs at a temperature about 0.9 MeV higher and is relatively weaker. The
effect of thermal shape fluctuations on the temperature dependence of
deformation is also studied. Relevant results for the level density parameter
are further presented.
  PACS numbers: 21.10.Ma, 21.60.-n, 27.70.+q

</DOC>
<DOC>
<DOCNO> 84290 </DOCNO>
Low-energy sector quantization of a massless scalar field outside a


  We quantize the low-energy sector of a massless scalar field in the
Reissner-Nordstrom spacetime. This allows the analysis of processes involving
soft scalar particles occurring outside charged black holes. In particular, we
compute the response of a static scalar source interacting with Hawking
radiation using the Unruh (and the Hartle-Hawking) vacuum. This response is
compared with the one obtained when the source is uniformly accelerated in the
usual vacuum of the Minkowski spacetime with the same proper acceleration. We
show that both responses are in general different in opposition to the result
obtained when the Reissner-Nordstrom black hole is replaced by a Schwarzschild
one. The conceptual relevance of this result is commented.

</DOC>
<DOC>
<DOCNO> 151376 </DOCNO>
Low-scale supergravity inflation with R-symmetry


  We study a supergravity model of inflation with R-symmetry and a single
scalar field, the inflaton, slowly rolling away from the origin. The scales of
inflation can be as low as the supersymmetry breaking scale of 10^10 GeV or
even the electroweak scale of 10^3 GeV which could be relevant in the context
of theories with submillimiter dimensions. Exact analytical solutions are
presented and a comparison with related models is given.

</DOC>
<DOC>
<DOCNO> 12381 </DOCNO>
Droplet States in the XXZ Heisenberg Chain


  We consider the ground states of the ferromagnetic XXZ chain with spin up
boundary conditions in sectors with a fixed number of down spins. This forces
the existence of a droplet of down spins in the system. We find the exact
energy and the states that describe these droplets in the limit of an infinite
number of down spins. We prove that there is a gap in the spectrum above the
droplet states. As the XXZ Hamiltonian has a gap above the fully magnetized
ground states as well, this means that the droplet states (for sufficiently
large droplets) form an isolated band. The width of this band tends to zero in
the limit of infinitely large droplets. We also prove the analogous results for
finite chains with periodic boundary conditions and for the infinite chain.

</DOC>
<DOC>
<DOCNO> 68957 </DOCNO>
LR Scalar Mixings and One-loop Neutrino Masses


  Within the framework of the complete theory of supersymmetry without
R-parity, where all possible R-parity violating terms are admitted, we perform
a systematic analytical study of all sources of neutrino masses up to ``direct
one-loop" (defined explicitly below) level. In the passing, we present the full
result for squark and slepton masses. In particular, there are interesting $LR$
squark and slepton mixings, which involve both bilinear and trilinear R-parity
violating parameters. The existence and important phenomenological implications
of such terms have been largely overlooked in previous studies. In particular,
in the studies under which either one type of the couplings is assumed to
vanish or neglected, the terms would not show up. The $LR$ mixings play a
central role in neutrino mass generation. Our results look straight forward to
be obtained, which, in our opinion, is an illustration of the effectiveness of
our formulation adopted.

</DOC>
<DOC>
<DOCNO> 9970 </DOCNO>
Critical Exponents of the KPZ Equation via Multi-Surface Coding


  We study the KPZ equation (in D = 2, 3 and 4 spatial dimensions) by using a
RSOS discretization of the surface. We measure the critical exponents very
precisely, and we show that the rational guess is not appropriate, and that 4D
is not the upper critical dimension. We are also able to determine very
precisely the exponent of the sub-leading scaling corrections, that turns out
to be close to 1 in all cases. We introduce and use a {\em multi-surface
coding} technique, that allow a gain of order 30 over usual numerical
simulations.

</DOC>
<DOC>
<DOCNO> 71418 </DOCNO>
b -> s \gamma and supersymmetry with large tan\beta


  We discuss the constraints on the supersymmetric parameter space from the
decay mode b -> s \gamma for large values of tan\beta. We improve the
theoretical prediction for the decay rate by summing very large radiative
corrections to all orders in perturbation theory. This extends the validity of
the perturbative calculation to the large tan\beta regime. This resummation of
terms of order alpha_s^n tan^{n+1}\beta uses a recently proposed effective
lagrangian for the Yukawa interaction of bottom quarks. Moreover, we identify
an additional source of tan\beta-enhanced terms, which are of order alpha_s
tan\beta and involve the charged Higgs boson, and analyze their behaviour in
higher orders of perturbation theory. After correcting the current expressions
for this rare decay branching ratio at next-to-leading order, we obtain that,
contrary to recent claims, the presently measured branching ratio of b -> s
\gamma constrains the supersymmetric parameter space in a relevant way, even if
tan\beta is large.

</DOC>
<DOC>
<DOCNO> 11714 </DOCNO>
Enhanced Valence Fluctuations Caused by f-c Coulomb Interaction in


  Properties of an extended periodic Anderson model with the f-c Coulomb
interaction $\Ufc$ is studied as a model for \Ge and related compounds which is
cosidered to exhibit a sharp valence change under pressure. The problem is
treated by extending the {\it slave-boson} and large-N expansion method to
treat the present system. It is shown that, as the f-level $\epsilon_{\rm f}$
is increased relative to the Fermi level, the sharp valence change is caused by
the effect of $\Ufc$ with moderate strength of the order of the bandwith of
conduction electrons. The superconducting transition temperature $T_\rc$ due to
the valence-fluctuation exchange is estimated on the slave-boson fluctuation
approximation. In the model with spherical Fermi surface, $T_\rc$ exhibits
sharp peak as a function of $\epsilon_{\rm f}$, simulating the effect of
pressure, for the d-wave pairing channel.

</DOC>
<DOC>
<DOCNO> 120872 </DOCNO>
Vortex solitons - Mass, Energy and Angular momentum bunching in


  It is shown that the interaction of large amplitude electromagnetic waves
with a hot electron-positron (e-p) plasma (a principal constituent of the
universe in the MeV epoch) leads to a bunching of mass, energy, and angular
momentum in stable, long-lived structures. Electromagnetism in the MeV epoch,
then, could provide a possible route for seeding the observed large-scale
structure of the universe.

</DOC>
<DOC>
<DOCNO> 102547 </DOCNO>
Orbits of Lie Group Actions are Weakly Embedded


  In this note we prove that whenever a Lie group $G$ acts on a manifold $X$,
then the orbit $Gx$ through any point $x$ of $X$ is a weakly embedded
submanifold of $X$. The investigation of this problem was inspired by an
application to Cat astrophe Theory.

</DOC>
<DOC>
<DOCNO> 83104 </DOCNO>
TSIA: A Dataflow Model


  The Task System and Item Architecture (TSIA) is a model for transparent
application execution. In many real-world projects, a TSIA provides a simple
application with a transparent reliable, distributed, heterogeneous, adaptive,
dynamic, real-time, parallel, secure or other execution. TSIA is suitable for
many applications, not just for the simple applications served to date. This
presentation shows that TSIA is a dataflow model - a long-standing model for
transparent parallel execution. The advances to the dataflow model include a
simple semantics, as well as support for input/output, for modifiable items and
for other such effects.

</DOC>
<DOC>
<DOCNO> 10999 </DOCNO>
Universal saturation of electron dephasing in three-dimensional


  We have systematically investigated the low-temperature electron dephasing
times $\tau_\phi$ in more than 40 three-dimensional polycrystalline impure
metals with distinct material characteristics. In all cases, a saturation of
the dephasing time is observed below about a (few) degree(s) Kelvin, depending
on samples. The value of the saturated dephasing time $\tau_0$ [$\equiv
\tau_\phi (T \to 0 {\rm K})$] falls basically in the range 0.005 to 0.5 ns for
all samples. Particularly, we find that $\tau_0$ scales with the electron
diffusion constant $D$ as $\tau_0 \sim D^{- \alpha}$, with $\alpha$ close to or
slightly larger than 1, for over two decades of $D$ from about 0.1 to 10
cm$^2$/s. Our observation suggests that the saturation behavior of $\tau_\phi$
is universal and intrinsic in three-dimensional polycrystalline impure metals.
A complete theoretical explanation is not yet available.

</DOC>
<DOC>
<DOCNO> 122723 </DOCNO>
The XMM-Newton Optical/UV Monitor Telescope


  The XMM-OM instrument extends the spectral coverage of the XMM-Newton
observatory into the ultraviolet and optical range. It provides imaging and
time-resolved data on targets simultaneously with observations in the EPIC and
RGS. It also has the ability to track stars in its field of view, thus
providing an improved post-facto aspect solution for the spacecraft. An
overview of the XMM-OM and its operation is given, together with current
information on the performance of the instrument.

</DOC>
<DOC>
<DOCNO> 8003 </DOCNO>
Theory of Ferromagnetism in Diluted Magnetic Semiconductor Quantum Wells


  We present a mean field theory of ferromagnetism in diluted magnetic
semiconductor quantum wells. When subband mixing due to exchange interactions
between quantum well free carriers and magnetic impurities is neglected,
analytic result can be obtained for the dependence of the critical temperature
and the spontaneous magnetization on the distribution of magnetic impurities
and the quantum well width. The validity of this approximate theory has been
tested by comparing its predictions with those from numerical self-consistent
field calculations. Interactions among free carriers, accounted for using the
local-spin-density approximation, substantially enhance the critical
temperature. We demonstrate that an external bias potential can tune the
critical temperature through a wide range.

</DOC>
<DOC>
<DOCNO> 102214 </DOCNO>
Sur l'homologie des espaces de noeuds non-compacts


  The spectral sequence constructed by V.A.Vassiliev computes the homology of
the spaces of non-compact knots in ${\bf R}^d$, $d\ge 3$. In this work the
first term of this spectral sequence is described in terms of the homology of
the Hochschild complex for the Poisson algebras operad, if d is odd (resp. for
the Gerstenhaber algebras operads, if d is even). In particular the bialgebra
of chord diagrams arises as some subspace of this homology (in this case d=3).
Also a simplification for the calculation of the Vassiliev spectral sequence in
the first term is provided.

</DOC>
<DOC>
<DOCNO> 71258 </DOCNO>
Four-neutrino model and the K2K experiment


  We investigate the neutrino oscillations of \nu_\mu beam at the K2K
experiment in the four-neutrino model with three active and one sterile
neutrinos, and compare them with the oscillations in the three-neutrino model.
In the four-neutrino case, the effect of the \Delta m^2_{LSND} scale of
mass-squared difference, derived from the LSND experiments, occurs in the
survival probability P(\nu_\mu \to \nu_\mu) in the range of \Delta m^2 < 0.004
eV^2, where \Delta m^2 is the relevant one to the K2K experiment and
corresponds to the atmospheric neutrino mass scale. Once the probability
P(\nu_\mu \to \nu_\mu) is measured at the K2K, the allowed region of \Delta m^2
would turn out to be broader in the four-neutrino model than the one in the
three-neutrino model.

</DOC>
<DOC>
<DOCNO> 10823 </DOCNO>
Relaxation of a Moving Contact Line and Landau-Levich Effect


  The dynamics of the deformations of a moving contact line is formulated. It
is shown that an advancing contact line relaxes more quickly as compared to the
equilibium case, while for a receding contact line there is a corresponding
slowing down. For a receding contact line on a heterogeneous solid surface, it
is found that a roughening transition takes place which formally corresponds to
the onset of leaving a Landau-Levich film.

</DOC>
<DOC>
<DOCNO> 80805 </DOCNO>
Broadening of the QCD3 flux tube from the AdS/CFT correspondence


  We use the finite temperature AdS/CFT approach to demonstrate logarithmic
broadening of the confining QCD3 flux tube as a function of quark separation.
This behavior indicates that, unlike lattice QCD, there is no roughening
transition in the AdS/CFT formulation, which raises the interesting possibility
of extrapolating strong coupling results to weak couplings by the use of
resummation techniques. In the zero-temperature non-confining limit, we find
that this logarithmic broadening of the field strength distribution is absent.
Our results are obtained numerically at strong couplings, in the supergravity
approximation.

</DOC>
<DOC>
<DOCNO> 117563 </DOCNO>
The Observations of Type Ia Supernovae


  The past ten years have seen a tremendous increase in the number of Type Ia
supernovae discovered and in the quality of the basic data presented. The
cosmological results based on distances to Type Ia events have been
spectacular, leading to statistically accurate values of the Hubble constant,
Omega_M, and Omega_Lambda. However, in spite of the recent advances, a number
of mysteries continue to remain in our understanding of these events. In this
short review, I will concentrate on unresolved problems and curious
correlations in the data on Type Ia SNe, whose resolution may lead to a deeper
understanding of the physical mechanism of the Type Ia supernova explosions.

</DOC>
<DOC>
<DOCNO> 11153 </DOCNO>
Normal State Properties of Cuprates: t-J Model vs. Experiment


  We discuss some recent results for the properties of doped antiferromagnets,
obtained within the planar t-J model mainly by the finite-temperature Lanczos
method, with the emphasis on the comparison with experimental results in
cuprates. Among the thermodynamic properties the chemical potential and entropy
are considered, as well as their relation to the thermoelectric power. At the
intermediate doping model results for the optical conductivity, the dynamical
spin structure factor and spectral functions reveal a marginal Fermi-liquid
behaviour, close to experimental findings. It is shown that the universal form
of the optical conductivity follows quite generally from the overdamped
character of single-particle excitations.

</DOC>
<DOC>
<DOCNO> 100371 </DOCNO>
Vector bundles on the cubic threefold


  Let X be a smooth cubic threefold, M the moduli space of stable rank 2 vector
bundles on X with trivial determinant and c_2=2 (the smallest value for which
this space is non-empty). Recent results of Druel, Iliev, Markushevich and
Tikhomirov lead to a precise description of M and its Maruyama compactification
M': the latter is isomorphic to the intermediate Jacobian of X blown-up along
the Fano surface. In this survey paper we explain these results and discuss
some applications.

</DOC>
<DOC>
<DOCNO> 11104 </DOCNO>
Angular dependence of the penetration depth in unconventional


  We examine the Meissner state nonlinear electrodynamic effects on the field
and angular dependence of the low temperature penetration depth, $\lambda$, of
superconductors in several kinds of unconventional pairing states, with nodes
or deep minima (``quasinodes'') in the energy gap. Our calculations are
prompted by the fact that, for typical unconventional superconducting material
parameters, the predicted size of these effects for $\lambda$ exceeds the
available experimental precision for this quantity by a much larger factor than
for others. We obtain expressions for the nonlinear component of the
penetration depth, $\Delta\lambda$, for different two- and three- dimensional
nodal or quasinodal structures. Each case has a characteristic signature as to
its dependence on the size and orientation of the applied magnetic field. This
shows that $\Delta\lambda$ measurements can be used to elucidate the nodal or
quasinodal structure of the energy gap. For nodal lines we find that
$\Delta\lambda$ is linear in the applied field, while the dependence is
quadratic for point nodes. For layered materials with
$\rm{YBa_2Cu_3O_{7-\delta}}$ (YBCO) type anisotropy, our results for the
angular dependence of $\Delta\lambda$ differ greatly from those for tetragonal
materials and are in agreement with experiment. For the two- and three-
dimensional quasinodal cases, $\Delta\lambda$ is no longer proportional to a
power of the field and the field and angular dependences are not separable,
with a suppression of the overall signal as the node is filled in.

</DOC>
<DOC>
<DOCNO> 118696 </DOCNO>
Bright X-ray bursts from 1E 1724-3045 in Terzan 2


  During about 3 years wide field monitoring of the Galactic Center region by
the WFC telescopes on board the BeppoSAX satellite, a total of 14 type-I X-ray
bursts were detected from the burster 1E 1724-3045 located in the globular
cluster Terzan 2. All the observed events showed evidence for photospheric
radius expansion due to Eddington-limit burst luminosity, thus leading to an
estimate of the source distance (~7.2 kpc). Preliminary results of the analysis
of the bursts are presented.

</DOC>
<DOC>
<DOCNO> 99401 </DOCNO>
Finite groups with the same character tables, Drinfel'd algebras and


  We prove that finite groups have the same complex character tables iff the
group algebras are twisted forms of each other as Drinfel'd quasi-bialgebras or
iff there is non-associative bi-Galois algebra over these groups. The
interpretations of class-preserving automorphisms and permutation
representations with the same character in terms of Drinfel'd algebras are also
given.

</DOC>
<DOC>
<DOCNO> 9437 </DOCNO>
Small-World Rouse Networks as models of cross-linked polymers


  We use the recently introduced small-world networks (SWN) to model
cross-linked polymers, as an extension of the linear Rouse-chain. We study the
SWN-dynamics under the influence of external forces. Our focus is on the
structurally and thermally averaged SWN stretching, which we determine both
numerically and analytically using a psudo-gap ansatz for the SWN-density of
states. The SWN stretching is related to the probability of a random-walker to
return to its origin on the SWN. We compare our results to the corresponding
ones for Cayley trees.

</DOC>
<DOC>
<DOCNO> 9807 </DOCNO>
Path Integral Approach to Strongly Nonlinear Composite


  We study strongly nonlinear disordered media using a functional method. We
solve exactly the problem of a nonlinear impurity in a linear host and we
obtain a Bruggeman-like formula for the effective nonlinear susceptibility.
This formula reduces to the usual Bruggeman effective medium approximation in
the linear case and has the following features: (i) It reproduces the weak
contrast expansion to the second order and (ii) the effective medium exponent
near the percolation threshold are $s=1$, $t=1+\kappa$, where $\kappa$ is the
nonlinearity exponent. Finally, we give analytical expressions for previously
numerically calculated quantities.

</DOC>
<DOC>
<DOCNO> 12639 </DOCNO>
Crossover behavior for long reptating polymers


  We analyze the Rubinstein-Duke model for polymer reptation by means of
density matrix renormalization techniques. We find a crossover behavior for a
series of quantities as function of the polymer length. The crossover length
may become very large if the mobility of end groups is small compared to that
of the internal reptons. Our results offer an explanation to a controversy
between theory, experiments and simulations on the leading and subleading
scaling behavior of the polymer renewal time and diffusion constant.

</DOC>
<DOC>
<DOCNO> 84402 </DOCNO>
Gravitational Radiation


  Gravity is one of the fundamental forces of Nature, and it is the dominant
force in most astronomical systems. In common with all other phenomena, gravity
must obey the principles of special relativity. In particular, gravitational
forces must not be transmitted or communicated faster than light. This means
that when the gravitational field of an object changes, the changes ripple
outwards through space and take a finite time to reach other objects. These
ripples are called gravitational radiation or gravitational waves. This article
gives a brief introduction to the physics of gravitational radiation, including
technical material suitable for non-specialist scientists.

</DOC>
<DOC>
<DOCNO> 150372 </DOCNO>
Gravity in the brane-world for two-branes model with stabilized modulus


  We present a complete scheme to discuss linear perturbations in the
two-branes model of the Randall and Sundrum scenario with the stabilization
mechanism proposed by Goldberger and Wise. We confirm that under the
approximation of zero mode truncation the induced metric on the branes
reproduces that of the usual 4-dimensional Einstein gravity. We also present
formulas to evaluate the mass spectrum and the contribution to the metric
perturbations from all the Kaluza-Klein modes. We also conjecture that the
model has tachyonic modes unless the background configuration for the bulk
scalar field introduced to stabilize the distance between the two branes is
monotonic in the fifth dimension.

</DOC>
<DOC>
<DOCNO> 12470 </DOCNO>
Peak positions and shapes in neutron pair correlation functions from


  The effect of the powder average on the peak shapes and positions in neutron
pair distribution functions of polycrystalline materials is examined. It is
shown that for highly anisotropic crystals, the powder average leads to shifts
in peak positions and to non-Gaussian peak shapes. The peak shifts can be as
large as several percent of the lattice spacing.

</DOC>
<DOC>
<DOCNO> 68340 </DOCNO>
A new approach to the evolution of cosmological perturbations on large


  We discuss the evolution of linear perturbations about a
Friedmann-Robertson-Walker background metric, using only the local conservation
of energy-momentum. We show that on sufficiently large scales the curvature
perturbation on spatial hypersurfaces of uniform-density is conserved when the
non-adiabatic pressure perturbation is negligible. This is the first time that
this result has been demonstrated independently of the gravitational field
equations. A physical picture of long-wavelength perturbations as being
composed of separate Robertson-Walker universes gives a simple understanding of
the possible evolution of the curvature perturbation, in particular clarifying
the conditions under which super-horizon curvature perturbations may vary.

</DOC>
<DOC>
<DOCNO> 12457 </DOCNO>
Variational quantum Monte Carlo calculations for solid surfaces


  Quantum Monte Carlo methods have proven to predict atomic and bulk properties
of light and non-light elements with high accuracy. Here we report on the first
variational quantum Monte Carlo (VMC) calculations for solid surfaces. Taking
the boundary condition for the simulation from a finite layer geometry, the
Hamiltonian, including a nonlocal pseudopotential, is cast in a layer resolved
form and evaluated with a two-dimensional Ewald summation technique. The exact
cancellation of all Jellium contributions to the Hamiltonian is ensured. The
many-body trial wave function consists of a Slater determinant with
parameterized localized orbitals and a Jastrow factor with a common two-body
term plus a new confinement term representing further variational freedom to
take into account the existence of the surface. We present results for the
ideal (110) surface of Galliumarsenide for different system sizes. With the
optimized trial wave function, we determine some properties related to a solid
surface to illustrate that VMC techniques provide standard results under full
inclusion of many-body effects at solid surfaces.

</DOC>
<DOC>
<DOCNO> 119293 </DOCNO>
The evolution Equation of Cosmological density perturbation in


  The evolution equation of linear cosmic density perturbations in the realm of
Einstein-Cartan theory of gravity is obtained.The de Sitter metric fluctuation
is computed in terms of the spin-torsion background density.

</DOC>
<DOC>
<DOCNO> 116651 </DOCNO>
Shuffling Yeast Gene Expression Data


  A new method to sort gene expression patterns into functional groups is
presented. The method is based on a sorting algorithm using a non-local
similarity score, which takes all other patterns in the dataset into account.
The method is therefore very robust with respect to noise. Using the expression
data for yeast, we extract information about functional groups. Without prior
knowledge of parameters the cell cycle regulated genes in yeast can be
identified. Furthermore a second, independent cell clock is identified. The
capability of the algorithm to extract information about signal flow in the
regulatory network underlying the expression patterns is demonstrated.

</DOC>
<DOC>
<DOCNO> 71304 </DOCNO>
Neutral Kaons in Medium: Decoherence Effects


  We consider departures from hamiltonian dynamics in the evolution of neutral
kaons due to their interactions with environment that generate entanglement
among them. We propose a phenomenological model of stochastic re-scattering and
estimate the coefficients of the effective hamiltonian and decoherence terms.
Finally we analyze the interplay between the weak interaction and matter
effects and propose the observables suitable to measure the matter
characteristics of CPT violation and decoherence.

</DOC>
<DOC>
<DOCNO> 9205 </DOCNO>
Photonic crystals of coated metallic spheres


  It is shown that simple face-centered-cubic (fcc) structures of both metallic
and coated metallic spheres are ideal candidates to achieve a tunable complete
photonic bandgap (CPBG) for optical wavelengths using currently available
experimental techniques. For coated microspheres with the coating width to
plasma wavelength ratio $l_c/\lambda_p \leq 10%$ and the coating and host
refractive indices $n_c$ and $n_h$, respectively, between 1 and 1.47, one can
always find a sphere radius $r_s$ such that the relative gap width $g_w$ (gap
width to the midgap frequency ratio) is larger than 5% and, in some cases,
$g_w$ can exceed 9%. Using different coatings and supporting liquids, the width
and midgap frequency of a CPBG can be tuned considerably.

</DOC>
<DOC>
<DOCNO> 69171 </DOCNO>
Soft-Gluon Angular Screening in Heavy-Quark Fragmentation


  A method to measure the suppression of soft-gluon radiation by a heavy quark
("dead cone") is discussed. We analyse this QCD phenomenon in the framework of
the HERA experiment using Monte Carlo simulations.

</DOC>
<DOC>
<DOCNO> 122346 </DOCNO>
Giant cluster arcs as a constraint on the scattering cross-section of


  We carry out ray tracing through five high resolution simulations of a galaxy
cluster to study how its ability to produce giant gravitationally lensed arcs
is influenced by the collision cross-section of its dark matter. In three cases
typical dark matter particles in the cluster core undergo between 1 and 100
collisions per Hubble time; two more explore the long (``collisionless'') and
short (``fluid'') mean free path limits. We study the size and shape
distributions of arcs and compute the cross-section for producing ``extreme''
arcs of various sizes. Even a few collisions per particle modify the core
structure enough to destroy the cluster's ability to produce long, thin arcs.
For larger collision frequencies the cluster must be scaled up to
unrealistically large masses before it regains the ability to produce giant
arcs. None of our models with self-interacting dark matter (except the
``fluid'' limit) is able to produce radial arcs; even the case with the
smallest scattering cross-section must be scaled to the upper limit of observed
cluster masses before it produces radial arcs. Apparently the elastic collision
cross-section of dark matter in clusters must be very small, below 0.1 cm^2
g^-1, to be compatible with the observed ability of clusters to produce both
radial arcs and giant arcs.

</DOC>
<DOC>
<DOCNO> 152646 </DOCNO>
Dark Energy in Extra Dimensions and String Theory: Consistency


  The smallness of the cosmological constant is one of the basic problems in
particle physics and cosmology. Various attempts have been made to explain this
mystery, but no satisfactory solution has been found yet. The appearance of
extra dimensions in the framework of brane world systems seems to provide some
new ideas to address this problem from a different point of view. We shall
discuss some of these new approaches and see whether or not they lead to an
improvement of the situation. We shall conclude that we are still far from a
solution of the problem.

</DOC>
<DOC>
<DOCNO> 8171 </DOCNO>
d-wave Superconductivity in the Hubbard Model


  The superconducting instabilities of the doped repulsive 2D Hubbard model are
studied in the intermediate to strong coupling regime with help of the
Dynamical Cluster Approximation (DCA). To solve the effective cluster problem
we employ an extended Non Crossing Approximation (NCA), which allows for a
transition to the broken symmetry state. At sufficiently low temperatures we
find stable d-wave solutions with off-diagonal long range order. The maximal
$T_c\approx 150K$ occurs for a doping $\delta\approx 20%$ and the doping
dependence of the transition temperatures agrees well with the generic
high-$T_c$ phase diagram.

</DOC>
<DOC>
<DOCNO> 10385 </DOCNO>
Out of Equilibrium Fields in Self-consistent Inflationary Dynamics.


  The physics during the inflationary stage of the universe is of quantum
nature involving extremely high energy densities. Moreover, it is out of
equilibrium on a fastly expanding dynamical geometry.We present in these
lectures non-perturbative out of equilibrium field theoretical methods in
cosmological universes. We then study the non-linear dynamics of quantum fields
in matter and radiation dominated FRW and de Sitter universes. We investigate
the explosive particle production due to spinodal instabilities and parametric
amplification in FRW and deSitter universes with and without symmetry breaking.
We show how the particle production is sensitive to the expansion of the
universe.We present a complete renormalization scheme for the equation of
motion and the energy momentum tensor in flat cosmologies. We then consider an
O(N) inflaton model coupled self-consistently to gravity in the semiclassical
approximation, with `new inflation' type initial conditions. We study the
dynamics self-consistently and non-perturbatively with non-equilibrium field
theory methods in the large N limit. We find that spinodal instabilities drive
the growth of non-perturbatively large quantum fluctuations which shut off the
inflationary growth of the scale factor. A very specific combination of these
large quantum fluctuations plus the inflaton zero mode assemble into a new
effective field. This new field behaves classically and it is the object which
actually rolls down. The metric perturbations during inflation are computed
using this effective field and the Bardeen variable for superhorizon modes
during inflation. We compute the amplitude and index for the spectrum of scalar
density and tensorperturbations and find for these models that the spinodal
instabilities are responsible for a `red' primordial spectrum.

</DOC>
<DOC>
<DOCNO> 120313 </DOCNO>
The Onset of Cluster Formation around Intermediate Mass Stars


  We present the results of a recent near-infrared survey of the fields
surrounding a large sample of intermediate-mass pre-main-sequence (Herbig
Ae/Be) stars. While late-type Be and Ae stars are never associated with
conspicuous groups of young lower mass stars, early-type Be stars are usually
found within rich clusters. This finding has been tested against possible
biases due to different mass sensitivity of the observations or dynamical
dissipation of the clusters around older stars. Our results suggest that
massive stars are preferentially produced in dense stellar clusters, possibly
by dynamical interaction rather than by standard gas accretion as in the case
of lower mass stars. The possibility that the observed correlation between
maximum stellar mass and cluster richness could be the results of random
sampling the cluster size spectrum and the stellar IMF is also discussed.
Future observational tests capable of discriminating between these two
competitive models are outlined.

</DOC>
<DOC>
<DOCNO> 118191 </DOCNO>
Comparing Galaxy Morphology at Ultraviolet and Optical Wavelengths


  We have undertaken an imaging survey of 34 nearby galaxies in far-ultraviolet
(FUV, ~1500A) and optical (UBVRI) passbands to characterize galaxy morphology
as a function of wavelength. This sample, which includes a range of classical
Hubble types from elliptical to irregular with emphasis on spirals at low
inclination angle, provides a valuable database for comparison with images of
high-z galaxies whose FUV light is redshifted into the optical and near-
infrared bands. Ultraviolet data are from the UIT Astro-2 mission. We present
images and surface brightness profiles for each galaxy, and we discuss the
wavelength-dependence of morphology for different Hubble types in the context
of understanding high-z objects. In general, the dominance of young stars in
the FUV produces the patchy appearance of a morphological type later than that
inferred from optical images. Prominent rings and circumnuclear star formation
regions are clearly evident in FUV images of spirals, while bulges, bars, and
old, red stellar disks are faint to invisible at these short wavelengths.
However, the magnitude of the change in apparent morphology ranges from
dramatic in early--type spirals with prominent optical bulges to slight in
late-type spirals and irregulars, in which young stars dominate both the UV and
optical emission. Starburst galaxies with centrally concentrated, symmetric
bursts display an apparent ``E/S0'' structure in the FUV, while starbursts
associated with rings or mergers produce a peculiar morphology. We briefly
discuss the inadequacy of the optically-defined Hubble sequence to describe FUV
galaxy images and estimate morphological k-corrections, and we suggest some
directions for future research with this dataset.

</DOC>
<DOC>
<DOCNO> 100547 </DOCNO>
Non-commutative Symplectic Geometry, Quiver varieties, and Operads


  Quiver varieties have recently appeared in various different areas of
Mathematics such as representation theory of Kac-Moody algebras and quantum
groups, instantons on 4-manifolds, and resolutions Kleinian singularities. In
this paper, we show that many important affine quiver varieties, e.g., the
Calogero-Moser space, can be imbedded as coadjoint orbits in the dual of an
appropriate infinite dimensional Lie algebra. In particular, there is an
infinitesimally transitive action of the Lie algebra in question on the quiver
variety. Our construction is based on an extension of Kontsevich's formalism of
`non-commutative Symplectic geometry'. We show that this formalism acquires its
most adequate and natural formulation in the much more general framework of
P-geometry, a `non-commutative geometry' for an algebra over an arbitrary
cyclic Koszul operad.

</DOC>
<DOC>
<DOCNO> 122844 </DOCNO>
Gas kinematics from spectroscopy with a wide slit: detecting nuclear


  Motivated by STIS observations of more than 50 nearby galactic nuclei, we
consider long-slit emission-line spectra when the slit is wider than the
instrumental PSF, and the target has arbitrarily large velocity gradients. The
finite width of the slit generates complex patterns in the spectra that can be
misinterpreted as coming from various physically distinct nuclear components,
but when interpreted correctly, they can have considerable diagnostic power.
For a thin disk in circular motion around a central galactic black hole (BH), a
characteristic artifact occurs in the spectrum at the outer edge of the BH's
sphere of influence. It betrays the presence of a BH, and allows us to develop
a new method for estimating its mass, which gives higher sensitivity to BH
detection than traditional methods.

</DOC>
<DOC>
<DOCNO> 118217 </DOCNO>
Discovery of high proper motion ancient white dwarfs: nearby massive


  We present the discovery and spectroscopic identification of two very high
proper motion ancient white dwarf stars, found in a systematic proper motion
survey. Their kinematics and apparent magnitude clearly indicate that they are
halo members, while their optical spectra are almost identical to the recently
identified cool Halo white dwarf WD0346+246. Canonical stellar halo models
predict a white dwarf volume density of two orders of magnitude less than the
approx 7*10^{-4} Solar masses per pc^{-3} inferred from this survey. With the
caveat that the sample size is very small, it appears that a significant
fraction, about 10%, of the local dark matter halo is in the form of very old,
cool, white dwarfs.

</DOC>
<DOC>
<DOCNO> 120582 </DOCNO>
The Shapley Supercluster. III. Collapse dynamics and mass of the central


  We present the first application of a spherical collapse model to a
supercluster of galaxies. Positions and redshifts of $\sim 3000$ galaxies in
the Shapley Supercluster (SSC) are used to define velocity caustics that limit
the gravitationally collapsing structure in its central part. This is found to
extend at least to $8 h^{-1}$ Mpc of the central cluster, A 3558, enclosing 11
ACO clusters. Infall velocities reach $\sim 2000$ km s$^{-1}$. Dynamical models
of the collapsing region are used to estimate its mass profile. An upper bound
on the mass, based on a pure spherical infall model, gives $M(<8 h^{-1}{\rm
Mpc})\,^{<}_{\sim}\,1.3\times 10^{16}h^{-1}M_\odot$ for an Einstein-de Sitter
(critical) Universe and $M(<8 h^{-1}{\rm Mpc})\,^{<}_{\sim}\,8.5\times
10^{15}h^{-1}M_\odot$ for an empty Universe. The model of Diaferio \& Geller
(1997), based on estimating the escape velocity, gives a significantly lower
value, $M(<8 h^{-1}{\rm Mpc})\approx 2.1\times 10^{15}h^{-1}M_\odot$, very
similar to the mass found around the Coma cluster by the same method (Geller et
al. 1999), and comparable to or slightly lower than the dynamical mass in the
virialized regions of clusters enclosed in the same region of the SSC. In both
models, the overdensity in this region is substantial, but far from the value
required to account for the peculiar motion of the Local Group with respect to
the cosmic microwave background.

</DOC>
<DOC>
<DOCNO> 152530 </DOCNO>
Black Hole entropy by the brick wall method in four and five dimensions


  Using the brick wall method we compute the statistical entropy of a scalar
field in a nontrivial background, in two different cases. These background are
generated by four and five dimensional black holes with four and three U(1)
charges respectively. The Bekenstein entropy formula is generally obeyed, but
corrections are discussed in the latter case.

</DOC>
<DOC>
<DOCNO> 123252 </DOCNO>
Structures in the RM sky


  Coherent structures in the distribution of the Faraday rotation measure of
extragalactic radio sources are isolated using wavelet transformation
technique. Signatures of the magnetic fields in the local (Orion) spiral arm,
the Sagittarius and Carina arms, the synchrotron Loop I and, possibly, the
Perseus arm have been revealed using the RM catalogues of Simard-Normandin et
al. (1981, 551 source)and Broten et al. (1988, 663 sources). Unlike earlier
analyses of the RM sky, our approach has allowed us to assess the stability of
the results with respect to modifications of the data sample.
  We estimate the mean magnetic field strength in the Orion arm as 1.4\pm0.3
mkGauss and find clear indication of a magnetic field reversal at a distance of
0.6-1 kpc towards the Galactic centre. Our analysis has revealed for the first
time the extension of the reversal in the Carina arm. The direction of magnetic
field in the Perseus arm is reversed with respect to that in the Orion arm. The
average pitch angle of magnetic field in the nearby spiral arms is 15^\circ,
and the mean field strength in the Sagittarius-Carina and Perseus arms is
1.7\pm0.3 mkGauss and 1.4\pm1.2 mkGauss, respectively. The line-of-sight
magnetic field in Loop I is estimated as 0.9\pm0.3 mkGauss. We find firm
evidence of a dominant even symmetry of the local mean field with respect to
the galactic equator.

</DOC>
<DOC>
<DOCNO> 40567 </DOCNO>
The 115 GeV Higgs Odyssey


  On his way home from Troy, Odysseus had arrived within reach of Ithaca when a
great storm blew up. He was swept away, and only several years later was he
able to return to reclaim his rights from the rapacious suitors, with the aid
of his son Telemachus. Some wonder whether this epic is repeating itself, if
the Higgs weighs 115 GeV. If so, are CMS and ATLAS cast in the role of
Telemachus? In this paper, I first discuss how close to Ithaca LEP may have
been, the fact that a 115 GeV Higgs boson would disfavour technicolour, its
potential implications for supersymmetry, and finally the prospects for
completing the Higgs Odyssey.

</DOC>
<DOC>
<DOCNO> 100659 </DOCNO>
Quiver Varieties and Yangians


  We prove a conjecture of Nakajima (for type A the result was announced by
Ginzburg- Vasserot) giving a geometric realization, via quiver varieties, of
the Yangian of type ADE (and more in general of the Yangian associated to every
symmetric Kac-Moody Lie algebra). As a corollary we get that tthe characters of
the simple finite dimensional representations of the quantized affine algebra
and that of the yangian coincide.

</DOC>
<DOC>
<DOCNO> 116931 </DOCNO>
Results on Plasma Focusing of High Energy Density Electron and Positron


  We present results from the SLAC E-150 experiment on plasma focusing of high
energy density electron and, for the first time, positron beams. We also
discuss measurements on plasma lens-induced synchrotron radiation, longitudinal
dynamics of plasma focusing, and laser- and beam-plasma interactions.

</DOC>
<DOC>
<DOCNO> 12060 </DOCNO>
Lattice vibrations and structural instability in Cesium near the cubic


  Under pressure cesium undergoes a transition from a high-pressure fcc phase
(Cs-II) to a collapsed fcc phase (Cs-III) near 4.2GPa. At 4.4GPa there follows
a transition to the tetragonal Cs-IV phase. In order to investigate the lattice
vibrations in the fcc phase and seek a possible dynamical instability of the
lattice, the phonon spectra of fcc-Cs at volumes near the III-IV transition are
calculated using Savrasov's density functional linear-response LMTO method.
Compared with quasiharmonic model calculations including non-central
interatomic forces up to second neighbours, at the volume $V/V_0= 0.44$ ($V_0$
is the experimental volume of bcc-Cs with $a_0$=6.048{\AA}), the
linear-response calculations show soft intermediate wavelength
$T_{[1\bar{1}0]}[{\xi}{\xi}0]$ phonons. Similar softening is also observed for
short wavelength $L[\xi\xi\xi]$ and $L[00\xi]$ phonons and intermediate
wavelength $L[\xi\xi\xi]$ phonons. The Born-von K\'{a}rm\'{a}n analysis of
dispersion curves indicates that the interplanar force constants exhibit
oscillating behaviours against plane spacing $n$ and the large softening of
intermediate wavelength $T_{[1\bar{1}0]}[{\xi}{\xi}0]$ phonons results from a
negative (110)-interplanar force-constant $\Phi_{n=2}$. The frequencies of the
$T_{[1\bar{1}0]}[{\xi}{\xi}0]$ phonons with $\xi$ around 1/3 become imaginary
and the fcc structure becomes dynamically unstable for volumes below $0.41V_0$.
It is suggested that superstructures corresponding to the $\mathbf{q}{\neq}0$
soft mode should be present as a precursor of tetragonal Cs-IV structure.

</DOC>
<DOC>
<DOCNO> 116479 </DOCNO>
Two Novel Special Relativistic Effects: Space Dilatation and Time


  The conventional discussion of the observed distortions of space and time in
Special Relativity (the Lorentz-Fitzgerald Contraction and Time Dilatation) is
extended by considering observations, from a stationary frame, of : (i) objects
moving with constant velocity and uniformly illuminated during a short time
$\tau_L$ (their `Luminous Proper Time') in their rest frame; these may be
called `Transient Luminous Objects' and (ii) a moving, extended, array of
synchronised `equivalent clocks' in a common inertial frame. Application of the
Lorentz Transformation to (i) shows that such objects, observed from the
stationary frame with coarse time resolution in a direction perpendicular to
their direction of motion are seen to be at rest but {\it longer} in the
direction of the relative velocity $\vec{v}$ by a factor $1/\sqrt{1-(v/c)^2}$
(Space Dilatation) and to (ii) that the moving equivalent clock at any fixed
position in the rest frame of the stationary observer is seen to be running
{\it faster} than a similar clock at rest by the factor $1/\sqrt{1-(v/c)^2}$
(Time Contraction). All four space-time `effects' of Special Relativity are
simply classified in terms of the projective geometry of space-time, and the
close analogy of these effects to linear spatial perspective is pointed out.

</DOC>
<DOC>
<DOCNO> 99471 </DOCNO>
Finite Group Modular Data


  In a remarkable variety of contexts appears the modular data associated to
finite groups. And yet, compared to the well-understood affine algebra modular
data, the general properties of this finite group modular data has been poorly
explored. In this paper we undergo such a study. We identify some senses in
which the finite group data is similar to, and different from, the affine data.
We also consider the data arising from a cohomological twist, and write down,
explicitly in terms of quantities associated directly with the finite group,
the modular S and T matrices for a general twist, for what appears to be the
first time in print.

</DOC>
<DOC>
<DOCNO> 70152 </DOCNO>
R-parity violation in $(t+\bar t)\tilde g$ production at LHC and


  We study the production of $(t+\bar{t}) \tilde{g}$ at the hadron colliders in
an R-parity ($R_{p}$) violating supersymmetric model. This process provides us
with information not only about $R_{p}$ violation, but may also help us in
detecting the supersymmetry itself. It is possible to detect an $R_{p}$
violating signal (with single gluino production) at the future hadron
colliders, such as Fermilab Tevatron Run II or CERN Large Hadron Collider
(LHC), if the parameters in the supersymmetric $\rlap/ R_{p}$ interactions are
not too small, e.g. for $m_{\tilde{g}}=1$ TeV, $\lambda^{''}=0.1$, still
hundreds of events are produced at LHC with luminosity $30 fb^{-1}$. Even if we
could not detect a signal of $ \rlap/R_{p}$ in the experiment, we get stringent
constraints on the heavy flavour $\rlap/R_{p}$ couplings. In addition to the
minimal supersymmetric standard model we have also considered some models with
a heavy gluino as the lightest supersymmetric particle.

</DOC>
<DOC>
<DOCNO> 11050 </DOCNO>
Interaction of quasilocal harmonic modes and boson peak in glasses


  The direct proportionality relation between the boson peak maximum in
glasses, $\omega_b$, and the Ioffe-Regel crossover frequency for phonons,
$\omega_d$, is established. For several investigated materials $\omega_b =
(1.5\pm 0.1)\omega_d$. At the frequency $\omega_d$ the mean free path of the
phonons $l$ becomes equal to their wavelength because of strong resonant
scattering on quasilocal harmonic oscillators. Above this frequency phonons
cease to exist. We prove that the established correlation between $\omega_b$
and $\omega_d$ holds in the general case and is a direct consequence of
bilinear coupling of quasilocal oscillators with the strain field.

</DOC>
<DOC>
<DOCNO> 40570 </DOCNO>
Search for Mixing and CP Violation in Charm Decays


  Standard model mixing and CP violation are expected to be small in the charm
sector. Some argue that only in the presence of new physics do we currently
expect to observe these effects. Fermilab experiment E791 has the largest
sample of reconstructed charm decays recorded to date. We have made an
exhaustive search for D0 D0-bar mixing and CP violation in this data. We
present the charm mixing limits on the mixing parameter r_mix using hadronic
and semileptonic decays, and also present preliminary limits on the CP
asymmetry parameter, A_CP, for Cabibbo suppressed decays.

</DOC>
<DOC>
<DOCNO> 10052 </DOCNO>
Band Gaps and Localization in Acoustic Propagation in Water with


  Multiple scattering of waves leads to many peculiar phenomena such as
complete band gaps in periodic structures and wave localization in disordered
media. Within a band gap excitations are evanescent; when localized they remain
confined in space until dissipated. Here we report acoustic band gap and
localization in a 2D system of air-cylinders in water. Exact numerical
calculations reveal the unexpected result that localization is relatively
independent of the precise location or organization of the scatterers.
Localization occurs within a finite region of frequencies, coincident with the
complete band gap predicted by a conventional band structure calculation for a
periodic lattice of scatterers. Inside the gap or localization regime, a
previously uninvestigated stable collective behavior of the cylinders appears.

</DOC>
<DOC>
<DOCNO> 170361 </DOCNO>
Fokker-Planck and Langevin Equations from Forward--Backward Path


  Starting from a forward--backward path integral of a point particle in a bath
of harmonic oscillators, we derive the Fokker-Planck and Langevin equations
with and without inertia. Special emphasis is placed upon the correct operator
order in the time evolution operator. The crucial step is the evaluation of a
Jacobian with a retarded time derivative by analytic regularization.

</DOC>
<DOC>
<DOCNO> 123110 </DOCNO>
Mapping the Galactic Halo III. Simulated Observations of Tidal Streams


  We have simulated the evolution of tidal debris in the Galactic halo in order
to guide our ongoing survey to determine the fraction of halo mass accreted via
satellite infall. Contrary to naive expectations that the satellite debris will
produce a single narrow velocity peak on a smooth distribution, there are many
different signatures of substructure, including multiple peaks and broad but
asymmetrical velocity distributions. Observations of the simulations show that
there is a high probability of detecting the presence of tidal debris with a
pencil beam survey of 100 square degrees. In the limiting case of a single 10^7
Msun satellite contributing 1% of the luminous halo mass the detection
probability is a few percent using just the velocities of 100 halo stars in a
single 1 square degree field. The detection probabilities scale with the
accreted fraction of the halo and the number of fields surveyed. There is also
surprisingly little dependence of the detection probabilities on the time since
the satellite became tidally disrupted, or on the initial orbit of the
satellite, except for the time spent in the survey volume.

</DOC>
<DOC>
<DOCNO> 68106 </DOCNO>
Higher-Order QCD Corrections in Prompt Photon Production


  We exhibit a method for simultaneously treating recoil and threshold
corrections in single-photon inclusive cross sections, working within the
formalism of collinear factorization. This approach conserves both the energy
and transverse momentum of resummed radiation. At moderate p_T, we find the
potential for substantial enhancements from higher-order perturbative and
power-law nonperturbative corrections.

</DOC>
<DOC>
<DOCNO> 117154 </DOCNO>
The second "Einstein paradox"


  Time invariance problem of a photon absorption process in atoms and molecules
is discussed.

</DOC>
<DOC>
<DOCNO> 122696 </DOCNO>
Recent CMB Observations and the Ionization History of the Universe


  Interest in non-standard recombination scenarios has been spurred by recent
cosmic microwave background (CMB) results from BOOMERANG and MAXIMA, which show
an unexpectedly low second acoustic peak, resulting in a best-fit baryon
density that is 50% larger than the prediction of big-bang nucleosynthesis
(BBN). This apparent discrepancy can be avoided if the universe has a
non-standard ionization history in which the recombination of hydrogen is
significantly delayed relative to the standard model. While future CMB
observations may eliminate this discrepancy, it is useful to develop a general
framework for analyzing non-standard ionization histories. We develop such a
framework, examining non-standard models in which the hydrogen binding energy
E_b and the overall expression for the time rate of change of the ionized
fraction of electrons are multiplied by arbitrary factors. This set of models
includes a number of previously-proposed models as special cases. We find a
wide range of models with delayed recombination that are able to fit the CMB
data with a baryon density in accordance with BBN, but there are even allowed
models with earlier recombination than in the standard model. A generic
prediction of these models is that the third acoustic CMB peak should be very
low relative to what is found in the standard model. This is the case even for
the models with earlier recombination than in the standard model, because here
the third peak is lowered by an increased diffusion damping at recombination
relative to the standard model. Interestingly, the specific height of the third
peak depends sensitively on the model parameters, so that future CMB
measurements will be able to distinguish between different non-standard
recombination scenarios.

</DOC>
<DOC>
<DOCNO> 84942 </DOCNO>
Cosmological Electromagnetic Fields due to Gravitational Wave


  We consider the dynamics of electromagnetic fields in an
almost-Friedmann-Robertson-Walker universe using the covariant and
gauge-invariant approach of Ellis and Bruni. Focusing on the situation where
deviations from the background model are generated by tensor perturbations
only, we demonstrate that the coupling between gravitational waves and a weak
magnetic test field can generate electromagnetic waves. We show that this
coupling leads to an initial pulse of electromagnetic waves whose width and
amplitude is determined by the wavelengths of the magnetic field and
gravitational waves. A number of implications for cosmology are discussed, in
particular we calculate an upper bound of the magnitude of this effect using
limits on the quadrapole anisotropy of the Cosmic Microwave Background.

</DOC>
<DOC>
<DOCNO> 118296 </DOCNO>
Long-term photometry of the Wolf-Rayet stars WR 137, WR 140, WR 148, and


  In 1991, a long term UBV-photometry campaign of four Wolf-Rayet stars was
started using the 60 cm telescope of the National Astronomical Observatory
Rozhen, Bulgaria. Here we report on our observational results and discuss the
light variations. The star WR 137 showed only random light variations, which
are probably due to dynamical wind instabilities but not to eclipses. WR 140
featured a dip in the light curve, the amplitude increasing towards shorter
wavelengths. The probable cause is electron and Rayleigh scattering when the
star was eclipsed by a dust envelope. In the case of WR 148 we found a period
of 4.3 days and significant scatter in the light curves. Additionally there
seems to be a long term variation with a period of 4 years. Our photometry of
WR 153 is consistent with the quadruple model for this star.

</DOC>
<DOC>
<DOCNO> 71790 </DOCNO>
The static PQCD potential with modified boundary conditions


  We calculate the potential between two static quarks in QCD using modified
boundary conditions for the perturbative expansion. Through a change of the
Feynman iepsilon prescription we effectively add a "sea" of gluons to the
asymptotic states with energies below a given scale Lambda. We find that the
standard result for the static potential gets corrections of order Lambda^2/Q^2
both at small and large momentum transfers Q^2. After resummation of the
infrared sensitive corrections we find that the running coupling alpha_s(Q^2)
freezes in the infrared and that the exchanged gluon gets an effective
tachyonic mass. We verify that identical results are obtained in the Coulomb
and Feynman gauges.

</DOC>
<DOC>
<DOCNO> 8343 </DOCNO>
Dynamical ordering in the c-axis in 3D driven vortex lattices


  We present molecular dynamics simulations of driven vortices in layered
superconductors in the presence of an external homogeneous force and point
disorder. We use a model introduced by J.R.Clem for describing 3D vortex lines
as stacks of 2D pancake vortices where only magnetic interactions are
considered and the Josephson interlayer coupling is neglected. We numerically
evaluate the long-range magnetic interaction between pancake vortices exactly.
We analyze the vortex correlation along the field direction on (c-axis). We
find that above the critical current, in the ``plastic flow'' regime, pancakes
are completely uncorrelated in the c-direction. When increasing the current,
there is an onset of correlation along the c-axis at the transition from
plastic flow to a moving smectic phase. This transition coincides with the peak
in the differential resistance.

</DOC>
<DOC>
<DOCNO> 120721 </DOCNO>
The Flared Disc Project: RXTE and ASCA Observations of X 1822-371


  We present archival RXTE and simultaneous ASCA data of the eclipsing low mass
X-ray binary (LMXB) X 1822-371. Our spectral analysis shows that a variety of
simple models can fit the spectra relatively well. Of these models, we explore
two in detail through phase resolved fits. These two models represent the case
of a very optically thick and a very optically thin corona. While systematic
residuals remain at high energies, the overall spectral shape is
well-approximated. The same two basic models are fit to the X-ray light curve,
which shows sinusoidal modulations interpreted as absorption by an opaque disc
rim of varying height. The geometry we infer from these fits is consistent with
previous studies: the disc rim reaches out to the tidal truncation radius,
while the radius of the corona (approximated as spherical) is very close to the
circularization radius. Timing analysis of the RXTE data shows a time lag from
hard to soft consistent with the coronal size inferred from the fits. Neither
the spectra nor the light curve fits allow us to rule out either model, leaving
a key ingredient of the X 1822-371 puzzle unsolved. Furthermore, while previous
studies were consistent with the central object being a 1.4 Msol neutron star,
which has been adopted as the best guess scenario for this system, our light
curve fits show that a white dwarf or black hole primary can work just as well.
Based on previously published estimates of the orbital evolution of X 1822-371,
however, we suggest that this system contains either a neutron star or a low
mass (~ 2.5 Msol) black hole and is in a transitional state of duration
shortward of 10^7 years.

</DOC>
<DOC>
<DOCNO> 71032 </DOCNO>
Bethe-Salpeter equation for diquarks in color-flavor locked phase of


  The Bethe-Salpeter equations for diquarks with the quantum numbers of the
Nambu-Goldstone bosons are analyzed in the color-flavor locked phase of cold
dense QCD with three quark flavors. The decay constants and the velocities of
the Nambu-Goldstone bosons are calculated in the Pagels-Stokar approximation.
It is also shown that, in contrast to the case of dense QCD with two flavors,
there are no massive radial excitations with quantum numbers of the
Nambu-Goldstone bosons in the color-flavor locked phase. The role of the
Meissner effect in the pairing dynamics of diquarks is explained.

</DOC>
<DOC>
<DOCNO> 169588 </DOCNO>
An Approach to Measurement by Quantum-Stochastic-Parameter Averaged


  A coarse-grained quantum operator technique is used along with the formalism
of Bohmian mechanics endowed with stochastic character at the quantum level in
order to address some central issues in the quantum theory of measurement. A
surprisingly simple picture of decoherence and EPR correlations emerges from
its use.

</DOC>
<DOC>
<DOCNO> 9372 </DOCNO>
Magnetic Field Dependent Optical Studies of a Layered Antiferromagnet


  Magnetic field ($H$)-dependent optical conductivity spectra $\sigma (\omega)
$ and dielectric constant spectra $\epsilon (\omega)$ of a layered
antiferromagnet ($A$-type) Pr$_{1/2}$Sr$_{1/2}$MnO$_3$ were presented. At 0.0 T
in 4.2 K, the $\sigma (\omega)$ showed a small Drude-like peak in the
far-infrared region and a broad absorption peak in the mid-infrared region.
With increasing $H$, large spectral weights were transferred from high to low
energy regions with increase of the Drude-like peak. We found that a polaron
picture could explain most of the $H$-dependent spectral changes. By comparing
with the $H$-dependent spectral weight changes and $\epsilon (\omega)$ of
Nd$_{1/2}$Sr$_{1/2}$MnO$_3$, which has the $CE$-type spin ordering, we showed
that a dimensional crossover from a 2-dimensional to a 3-dimensional metal
occurs in Pr$_{1/2}$Sr$_{1/2}$MnO$_3$.

</DOC>
<DOC>
<DOCNO> 152047 </DOCNO>
Sigma Model Corrections to the Confining Background


  Sigma model ($\alpha^{\prime}$) corrections to the confining string
background are obtained. The main result is that the Poincar\'e invariant
ansatz is maintained. Physical conditions for the dissapearance of the naked
singularity are discussed.

</DOC>
<DOC>
<DOCNO> 12180 </DOCNO>
An Electron Spin Resonance Selection Rule for Spin-Gapped Systems


  The direct electron spin resonance (ESR) absorption between a singlet ground
state and the triplet excited states of spin gap systems is investigated. Such
an absorption, which is forbidden by the conservation of the total spin quantum
number in isotropic Hamiltonians, is allowed by the Dzyaloshinskii-Moriya
interaction. We show a selection rule in the presence of this interaction,
using the exact numerical diagonalization of the finite cluster of the
quasi-one-dimensional bond-alternating spin system. The selection rule is also
modified into a suitable form in order to interpret recent experimental results
on CuGeO$_3$ and NaV$_2$O$_5$.

</DOC>
<DOC>
<DOCNO> 101406 </DOCNO>
A property of the skein polynomial with an application to contact


  We prove a finiteness property of the values of the skein polynomial of
homogeneous knots which allows to establish large classes of such knots to have
arbitrarily unsharp Bennequin inequality (for the Thurston-Bennequin invariant
of any of their Legendrian embeddings in the standard contact structure of
R^3), and a give a short proof that there are only finitely many among these
knots that have given genus and given braid index.

</DOC>
<DOC>
<DOCNO> 121413 </DOCNO>
VLT search for the infrared counterpart of 1E 1740.7-2942


  We report the results of our search for the near infrared counterpart of the
microquasar 1E 1740.7-2942 using the VLT (Based on observations collected at
the European Southern Observatory, Chile (ESO No 63.H-0261)). For the first
time, several counterpart candidates have been found in our Ks-band images that
may be consistent with the best radio and X-ray positions available for 1E
1740.7-2942. However, the non-detection of variability between two observing
epochs and the positional uncertainty still remaining at the nearly less than 1
arcsec level prevent us from identifying an unambiguous counterpart.
Alternatively, the VLT images set new upper limits significantly deeper than
previously reported that constrain the binary companion to be later than B8 V
or earlier than G5 III.

</DOC>
<DOC>
<DOCNO> 99522 </DOCNO>
Fixed points of analytic actions of supersoluble Lie groups on compact


  We show that every real analytic action of a connected supersoluble Lie group
on a compact surface with nonzero Euler characteristic has a fixed point. This
implies that E. Lima's fixed point free $C^{\infty}$ action on $S^2$ of the
affine group of the line cannot be approximated by analytic actions. An example
is given of an analytic, fixed point free action on $S^2$ of a solvable group
that is not supersoluble.

</DOC>
<DOC>
<DOCNO> 71219 </DOCNO>
Current fragmentation in semiinclusive leptoproduction


  Current fragmentation in semiinclusive deep inelastic leptoproduction offers,
besides refinement of inclusive measurements such as flavor separation and
access to the chiral-odd quark distribution functions $h_1^q(x) = \delta q(x)$,
the possibility to investigate intrinsic transverse momentum of hadrons via
azimuthal asymmetries.

</DOC>
<DOC>
<DOCNO> 70697 </DOCNO>
Recent Theoretical Developments in LEP 2 Physics


  Recent theoretical developments in electron-positron annihilation into
fermion pairs are summarized. In particular, two-fermion production, DPA for WW
signal, single-W production and ZZ signal

</DOC>
<DOC>
<DOCNO> 70086 </DOCNO>
Ultra High Energy Cosmic Rays from Compact Sources


  The clustering of ultra high energy (above 10^20 eV) cosmic rays (UHECR)
suggests that they might be emitted by compact sources. Statistical analysis of
Dubovsky et al. (Phys. Rev. Lett. 85 (2000) 1154) estimated the source density.
We extend their analysis to give also the confidence intervals for the number
of sources using a.) no assumptions on the relationship between clustered and
unclustered events; b.) nontrivial distributions for the source intensities and
energies; c.) the energy dependence of the propagation. We determine the
probability that a proton created at a distance r with energy E arrives at
earth above a threshold E_c. Using this function one can determine the observed
spectrum just by one numerical integration for any injection spectrum. The
observed 14 UHECR events above 10^20 eV with one doublet gives for the source
densities 180_-165^+2730*10^-3 Mpc^-3 (on the 68% confidence level). We present
detailed results for future experiments with larger UHECRs statistics.

</DOC>
<DOC>
<DOCNO> 169805 </DOCNO>
The Coulomb - harmonic oscillator correspondence in PT-symmetric quantum


  We show that and how the Coulomb potential can be regularized and solved
exactly at the imaginary couplings. The new spectrum of energies is real and
bounded as expected, but its explicit form proves totally different from the
usual real-coupling case.

</DOC>
<DOC>
<DOCNO> 11298 </DOCNO>
Mesoscale magnetism at the grain boundaries in colossal magnetoresistive


  We report the discovery of mesoscale regions with distinctive magnetic
properties in epitaxial La$_{1-x}$Sr$_{x}$MnO$_{3}$ films which exhibit
tunneling-like magnetoresistance across grain boundaries. By using
temperature-dependent magnetic force microscopy we observe that the mesoscale
regions are formed near the grain boundaries and have a different Curie
temperature (up to 20 K {\it higher}) than the grain interiors. Our images
provide direct evidence for previous speculations that the grain boundaries in
thin films are not magnetically and electronically sharp interfaces. The size
of the mesoscale regions varies with temperature and nature of the underlying
defect.

</DOC>
<DOC>
<DOCNO> 118458 </DOCNO>
Galactic contamination in the QMAP experiment


  We quantify the level of foreground contamination in the QMAP Cosmic
Microwave Background (CMB) data with two objectives: (a) measuring the level to
which the QMAP power spectrum measurements need to be corrected for foregrounds
and (b) using this data set to further refine current foreground models. We
cross-correlate the QMAP data with a variety of foreground templates. The 30
GHz Ka-band data is found to be significantly correlated with the Haslam 408
MHz and Reich and Reich 1420 MHz synchrotron maps, but not with the Diffuse
Infrared Background Experiment (DIRBE) 240, 140 and 100 micron maps or the
Wisconsin H-Alpha Mapper (WHAM) survey. The 40 GHz Q-band has no significant
template correlations. We discuss the constraints that this places on
synchrotron, free-free and dust emission. We also reanalyze the
foreground-cleaned Ka-band data and find that the two band power measurements
are lowered by 2.3% and 1.3%, respectively.

</DOC>
<DOC>
<DOCNO> 122720 </DOCNO>
Mid-Infrared observations of GRS 1915+105 and SS433


  We have observed in the mid-infrared (4-18 micron) the counterpart of the
compact object GRS 1915+105, and the western jet of SS433. The images were
carried out with the ISOCAM infrared camera on board of the Infrared Space
Observatory (ISO). The mid-infrared photometry of GRS 1915+105 shows the
presence of an additional contribution besides the synchrotron emission. The 15
micron images of the large-scale western lobe of the SS433/W50 nebula are
compared to the radio and X-ray ones. They show infrared synchrotron emission
on the western edge of SS433/W50 lobe.

</DOC>
<DOC>
<DOCNO> 13687 </DOCNO>
Hydrostatic pressure influence on dielectric permittivity of KH2PO4 and


  We measured transverse and longitudinal dielectric permittivities of KDP and
DKDP in the piezoelectric resonance frequency region under the hydrostatic
pressure. The transverse permittivity decreases with pressure in the
paraelectric phase and increases in the ferroelectric phase. The pressure
dependence of the transverse permittivity of deuterated DKDP is well described
by the presented theory. The longitudinal permittivity of a pure KDP exhibits
several peaks in the vicinity of the transition point. Upon increasing
hydrostatic pressure, the peaks get closer and may merge.

</DOC>
<DOC>
<DOCNO> 84873 </DOCNO>
Generic Isolated Horizons and their Applications


  Boundary conditions defining a generic isolated horizon are introduced. They
generalize the notion available in the existing literature by allowing the
horizon to have distortion and angular momentum. Space-times containing a black
hole, itself in equilibrium but possibly surrounded by radiation, satisfy these
conditions. In spite of this generality, the conditions have rich consequences.
They lead to a framework, somewhat analogous to null infinity, for extracting
physical information, but now in the \textit{strong} field regions. The
framework also generalizes the zeroth and first laws of black hole mechanics to
more realistic situations and sheds new light on the `origin' of the first law.
Finally, it provides a point of departure for black hole entropy calculations
in non-perturbative quantum gravity.

</DOC>
<DOC>
<DOCNO> 7776 </DOCNO>
Origin of the singular Bethe ansatz solutions for the Heisenberg XXZ


  We investigate symmetry properties of the Bethe ansatz wave functions for the
Heisenberg $XXZ$ spin chain. The $XXZ$ Hamiltonian commutes simultaneously with
the shift operator $T$ and the lattice inversion operator $V$ in the space of
$\Omega=\pm 1$ with $\Omega$ the eigenvalue of $T$. We show that the Bethe
ansatz solutions with normalizable wave functions cannot be the eigenstates of
$T$ and $V$ with quantum number $(\Omega,\Upsilon)=(\pm 1,\mp 1)$ where
$\Upsilon$ is the eigenvalue of $V$. Therefore the Bethe ansatz wave functions
should be singular for nondegenerate eigenstates of the Hamiltonian with
quantum number $(\Omega,\Upsilon)=(\pm 1,\mp 1)$. It is also shown that such
states exist in any nontrivial down-spin number sector and that the number of
them diverges exponentially with the chain length.

</DOC>
<DOC>
<DOCNO> 121851 </DOCNO>
An evolutionary scenario for the U Scorpii


  We perform evolutionary calculations of binary stars to find progenitors of
systems with parameters similar to the recurrent novae U Sco. We show that a U
Sco type-system may be formed starting with an initial binary system which has
a low-mass carbon-oxygen white dwarf as an accretor. Since the evolutionary
stage of the secondary is not well known, we calculate sequences with hydrogen
rich and helium rich secondaries. The evolution of the binary may be devided
into several observable stages as: classical nova, supersoft X-ray source with
hydrogen stable burning and strong wind phases, ending up with the formation of
a massive white dwarf near the Chandrasekhar mass limit. We follow the chemical
evolution of the secondary as well as of the matter lost from the system, and
we show that observed ^{12}C/^{13}C and N/C ratios may give some information
about the nature of the binary.

</DOC>
<DOC>
<DOCNO> 72106 </DOCNO>
A Note on Gaugino Masses in Kaluza-Klein/Radion Mediated SUSY Breaking


  We review the equivalence of two approaches to study theories with gauge
fields in extra spatial dimensions, namely the ``4D'' approach (with KK states)
and the ``5D'' approach (with matching to the 4D theory at the compactification
scale). In particular, we reiterate that there are two different power-law
scalings of ``effective'' gauge couplings. In a supersymmetric framework with
SUSY breaking in the radius modulus, i.e., the field which fixes the size of
the extra dimensions, these two approaches seem to give gaugino masses at
loop-level (with a possible enhancement due to large number of Kaluza-Klein
states) (hep-ph/0008069), and tree-level (hep-ph/0008103), respectively. We
show explicitly how this discrepancy can be resolved.

</DOC>
<DOC>
<DOCNO> 69251 </DOCNO>
Two photon background for Higgs boson searches at the LHC


  The search for an intermediate mass Higgs boson at the LHC needs the
quantitative understanding of the two-photon background. A calculation of
two-photon production in hadronic collisions at full next-to-leading order is
described. It includes photons originating from the hadronization of QCD
partons which play an important role at the LHC. A prediction for the invariant
mass distribution for photon pairs at the LHC is presented and finally the
residual scale dependencies are discussed.

</DOC>
<DOC>
<DOCNO> 100577 </DOCNO>
Locally nonconical convexity


  There is a hierarchy of structure conditions for convex sets. In this paper
we study a recently defined [3, 8, 9] condition called locally nonconical
convexity (abbreviated LNC). Is is easy to show that every strictly convex set
is LNC, as are half-spaces and finite intersections of sets of either of these
types, but many more sets are LNC. For instance, every zonoid (the range of a
nonatomic vector-valued measure) is LNC (Corollary 34). However, there are no
infinite-dimensional compact LNC sets (Theorem 23).
  The LNC concept originated in a search for continuous sections, and the
present paper shows how it leads naturally (and constructively) to continuous
sections in a variety of situations. Let Q be a compact, convex set in
R^n, and let T be a linear map from R^n into R^m.
We show (Theorem 1) that Q is LNC if and only if the restriction of any such T
to Q is an open map of Q onto T(Q). This implies that if Q is LNC, then any
such T has continuous sections (i.e. there are continuous right inverses of T)
that map from T(Q) to Q, and in fact it is possible to define continuous
sections constructively in various natural ways (Theorem 3, Corollary 4, and
Theorem 5). If Q is strictly convex and T is not 1-1, we can construct
continuous sections which take values in the boundary of Q (Theorem 6).
  When we give up compactness it is natural to consider a closed, convex, LNC
subset Q of a Hilbert space X which may be infinite-dimensional. In this case
we must assume that T is left Fredholm, i.e. a bounded linear map with closed
range and finite-dimensional kernel. We can then prove results analogous to
those mentioned in the last paragraph (Theorems 16-20). We also prove that T(Q)
is LNC (Theorem 25).

</DOC>
<DOC>
<DOCNO> 152377 </DOCNO>
Quantum Corrections to Noncommutative Solitons


  Noncommutative solitons are easier to find in a noncommutative field theory.
Similarly, the one-loop quantum corrections to the mass of a noncommutative
soliton are easier to compute, in a real scalar theory in 2+1 dimensions. We
carry out this computation in this paper. We also discuss the model with a
double-well potential, and conjecture that there is a partial symmetry
restoration in a vacuum state.

</DOC>
<DOC>
<DOCNO> 12373 </DOCNO>
Validity of the Hohenberg Theorem for a Generalized Bose-Einstein


  Several authors have considered the possibility of a generalized
Bose-Einstein condensation (BEC) in which a band of low states is occupied so
that the total occupation number is macroscopic, even if the occupation number
of each state is not extensive. The Hohenberg theorem (HT) states that there is
no BEC into a single state in 2D; we consider its validity for the case of a
generalized condensation and find that, under certain conditions, the HT does
not forbid a BEC in 2D. We discuss whether this situation actually occurs in
any theoretical model system.

</DOC>
<DOC>
<DOCNO> 68307 </DOCNO>
Anomalous processes at high temperature and density in a 2-dimensional


  We use the 2-dimensional $\sigma$ model as a toy model to study the behavior
of anomalous amplitudes in the limit where the constituent quark mass is small.
Symmetry arguments tell that the $\pi^o\to\gamma$ amplitude should vanish if
$m\to 0$, but we show that this conclusion is spoiled by infrared
singularities. When a proper regularization (resummation of a thermal mass, for
instance) is taken into account, this amplitude vanishes as expected. We also
study the amplitude $\pi^o\sigma\to\gamma$ and show that it does not vanish in
the same limit.

</DOC>
<DOC>
<DOCNO> 9118 </DOCNO>
Dynamics of structural models with a long-range interaction: glassy


  By making use of the Langevin dynamics and its generating functional (GF)
formulation the influence of the long-range nature of the interaction on the
tendency of the glass formation is systematically investigated. In doing so two
types of models is considered: (i) the non-disordered model with a pure
repulsive type of interaction and (ii) the model with a randomly distributed
strength of interaction (a quenched disordered model). The long-ranged
potential of interaction is scaled with a number of particles $N$ in such a way
as to enable for GF the saddle-point treatment as well as the systematic 1/N -
expansion around it. We show that the non-disordered model has no glass
transition which is in line with the mean-field limit of the mode - coupling
theory (MCT) predictions. On the other hand the model with a long-range
interaction which above that has a quenched disorder leads to MC - equations
which are generic for the $p$ - spin glass model and polymeric manifold in a
random media.

</DOC>
<DOC>
<DOCNO> 118052 </DOCNO>
Neutrino astronomy with the MACRO detector


  High energy gamma ray astronomy is now a well established field and several
sources have been discovered in the region from a few GeV up to several TeV. If
sources involving hadronic processes exist, the production of photons would be
accompanied by neutrinos too. Other possible neutrino sources could be related
to the annihilation of WIMPs at the center of galaxies with black holes.
  We present the results of a search for point-like sources using 1100
upward-going muons produced by neutrino interactions in the rock below and
inside the MACRO detector in the underground Gran Sasso Laboratory. These data
show no evidence for a possible neutrino point-like source or for possible
correlations between gamma ray bursts and neutrinos. They have been used to set
flux upper limits for candidate point-like sources which are in the range
10^-14-10^-15 cm-2 s-1.

</DOC>
<DOC>
<DOCNO> 40332 </DOCNO>
Low-background applications of MICROMEGAS detector technology


  The MICROMEGAS detector concept, generally optimized for use in accelerator
experiments, displays a peculiar combination of features that can be
advantageous in several astroparticle and neutrino physics applications. Their
sub-keV ionization energy threshold, excellent energy and space resolution, and
a simplicity of design that allows the use of radioclean materials in their
construction are some of these characteristics. We envision tackling
experimental challenges such as the measurement of neutral-current
neutrino-nucleus coherent scattering or Weakly Interacting Massive Particle
(WIMP) detectors with directional sensitivity. The large physics potential of a
compact (total volume O(1)m$^{3}$), multi-purpose array of low-background
MICROMEGAS is made evident.

</DOC>
<DOC>
<DOCNO> 10782 </DOCNO>
Theory of interlayer tunneling in bi-layer quantum Hall ferromagnets


  Spielman et al. have recently observed a large zero-bias peak in the tunnel
conductance of a bi-layer system in a quantum Hall ferromagnet state. We argue
that disorder-induced topological defects in the pseudospin order parameter
limit the peak size and destroy the predicted Josephson effect. We predict that
the peak would be split and shifted by an in-plane magnetic field in a way that
maps the dispersion relation of the ferromagnet's Goldstone mode. We also
predict resonant structures in the DC I-V characteristic under bias by an {\em
ac} electric field.

</DOC>
<DOC>
<DOCNO> 68016 </DOCNO>
Can we predict the fate of the Universe?


  We re-analyze the question of the use of cosmological observations to infer
the present state and future evolution of our patch of the universe. In
particular, we discuss under which conditions one might be able to infer that
our patch will enter an inflationary stage, as a prima facie interpretation of
the Type Ia supernovae and CMB data would suggest. We then establish a
`physical' criterion for the existence of inflation, to be contrasted with the
more `mathematical' one recently proposed by Starkman et al. \cite{STV}.

</DOC>
<DOC>
<DOCNO> 150622 </DOCNO>
A New Supersymmetric Compactification of Chiral IIB Supergravity


  We present a new compactification of chiral, N=2 ten-dimensional supergravity
down to five dimensions and show that it corresponds to the N=2 supersymmetric
critical point of five-dimensional, N=8 gauged supergravity found in [KPW].
This solution presented here is of particular significance because it involves
non-zero tensor gauge fields and, via the AdS/CFT correspondence, is dual to
the non-trivial N=1 supersymmetric fixed point of N=4 Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 117321 </DOCNO>
Dynamical calculation of direct muon-transfer rates from thermalized


  We perform dynamical calculations of direct muon-transfer rates from
thermalized muonic hydrogen isotopes to bare nuclei C$^{6+}$ and O$^{8+}$. For
these three-body charge-transfer reactions with Coulomb interaction in the
final state we use two-component integro-differential Faddeev-Hahn-type
equations in configuration space using close-coupling approximation. To take
into account the high polarizability of the muonic hydrogen due to the large
charge of the incident nuclei, a polarization potential is included in the
elastic channel. The large final-state Coulomb interaction is explicitly
included in the transfer channel. The transfer rates so calculated are in good
agreement with recent experiments.

</DOC>
<DOC>
<DOCNO> 13013 </DOCNO>
Decay of metastable phase on heterogeneous centers with continuous


  A system of a metastable phase with a pseudo continuous set of the
heterogeneous centers is considered. An analytical theory for kinetics of decay
of the metastable phase in such a system is constructed. The free energy of
formation of a critical embryo is assumed to be known in the macroscopic
approach as well as the solvatation energy. The theory constructed below is
based on the quasistationary approximation for the nucleation rate.

</DOC>
<DOC>
<DOCNO> 10945 </DOCNO>
Rheothermodynamics of transient networks


  The transient network model of Green-Tobolsky [1946], Yamamoto [1956] and
Tanaka-Edwards [1992] is formulated within the frame of thermodynamics of
irreversible processes, using as a fundamental quantity the chemical potential
associated to the connection of strands to the network and treating these
connections as chemical-like reactions. All thermodynamic quantities are thus
naturally defined in and out of equilibrium. Constitutive equations are
derived, giving the stress and the heat production as functions of the
thermomechanical history. The Clausius-Duhem inequality, stating that the
source of entropy is non-negative, is shown to hold for any thermomechanical
history, ensuring the thermodynamic consistency of our model. The presented
model includes the Green-Tobolsky model, whereas those of Yamamoto and
Tanaka-Edwards fit within ours on the condition that their free parameters obey
a detailed balance condition stemming form Boltzmann equilibrium statistics.

</DOC>
<DOC>
<DOCNO> 169571 </DOCNO>
Adiabatic Output Coupling of a Bose Gas at Finite Temperatures


  We develop a general theory of adiabatic output coupling from trapped atomic
Bose-Einstein Condensates at finite temperatures. For weak coupling, the output
rate from the condensate, and the excited levels in the trap, settles in a time
proportional to the inverse of the spectral width of the coupling to the output
modes. We discuss the properties of the output atoms in the quasi-steady-state
where the population in the trap is not appreciably depleted. We show how the
composition of the output beam, containing condensate and thermal component,
may be controlled by changing the frequency of the output coupler. This
composition determines the first and second order coherence of the output beam.
We discuss the changes in the composition of the bose gas left in the trap and
show how nonresonant output coupling can stimulate either the evaporation of
thermal excitations in the trap or the growth of non-thermal excitations, when
pairs of correlated atoms leave the condensate.

</DOC>
<DOC>
<DOCNO> 11440 </DOCNO>
Spontaneous magnetisation in the plane


  The Arak process is a solvable stochastic process which generates coloured
patterns in the plane. Patterns are made up of a variable number of random
non-intersecting polygons. We show that the distribution of Arak process states
is the Gibbs distribution of its states in thermodynamic equilibrium in the
grand canonical ensemble. The sequence of Gibbs distributions form a new model
parameterised by temperature. We prove that there is a phase transition in this
model, for some non-zero temperature. We illustrate this conclusion with
simulation results. We measure the critical exponents of this off-lattice model
and find they are consistent with those of the Ising model in two dimensions.

</DOC>
<DOC>
<DOCNO> 83239 </DOCNO>
Type Classes and Constraint Handling Rules


  Type classes are an elegant extension to traditional, Hindley-Milner based
typing systems. They are used in modern, typed languages such as Haskell to
support controlled overloading of symbols. Haskell 98 supports only
single-parameter and constructor type classes. Other extensions such as
multi-parameter type classes are highly desired but are still not officially
supported by Haskell. Subtle issues arise with extensions, which may lead to a
loss of feasible type inference or ambiguous programs. A proper logical basis
for type class systems seems to be missing. Such a basis would allow extensions
to be characterised and studied rigorously. We propose to employ Constraint
Handling Rules as a tool to study and develop type class systems in a uniform
way.

</DOC>
<DOC>
<DOCNO> 117776 </DOCNO>
The Effect of a Non-Thermal Tail on the Sunyaev-Zeldovich Effect in


  We study the spectral distortions of the cosmic microwave background
radiation induced by the Sunyaev-Zel'dovich (SZ) effect in clusters of galaxies
when the target electrons have a modified Maxwell-Boltzmann distribution with a
high-energy non-thermal tail. Bremsstrahlung radiation from this type of \\
electron distribution may explain the supra-thermal X-ray emission observed in
some clusters such as the Coma cluster and A2199 and serve as an alternative to
the classical but problematic inverse Compton scattering interpretation. We
show that the SZ effect can be used as a powerful tool to probe the electron
distribution in clusters of galaxies and discriminate among these different
interpretations of the X-ray excess. The existence of a non-thermal tail can
have important consequences for cluster based estimators of cosmological
parameters.

</DOC>
<DOC>
<DOCNO> 84631 </DOCNO>
On the Tensor Field Inflation in the GR Homogeneous Cosmological Model


  The homogeneous cosmological model in GR is proposed, where the vacuum
energy, which can cause the inflation, is described by tensor field rather than
by commonly used in inflationary scenarios scalar field. It is shown that if
the initial values of the field are sufficiently big (comparable with the
Planck units), under the condition of the tensor field's slow change in the
beginning the regime of the quasiexponential inflation can exist. Numerical
solutions for the inflationary stage are obtained that confirm the validity of
the approximate solutions. Inflation takes place under wide range of initial
conditions provided that the tensor field satisfies the condition imposed on
the initial values of the tensor field ${\phi^0}_0(0)\approx -{\phi^i}_i(0)$
(i=1,2,3). That condition also arises from the requirement to satisfy existing
observational data.

</DOC>
<DOC>
<DOCNO> 121710 </DOCNO>
Evolution of globular cluster systems in elliptical galaxies. II.


  We have studied the evolution of globular cluster systems (GCS) in elliptical
galaxies with a power-law initial GCS mass function (GCMF) ($f(M) \propto
M^{-\alpha}$) similar to that predicted by some theoretical studies of globular
clusters formation and to that of young cluster systems observed in merging
galaxies. We have carried out a survey over a large number of different host
galaxies and we have considered different values for the index, $\alpha$, of
the initial power-law GCMF ($\alpha=1.5,1.8,2.0$); we show the dependence of
the main GCS final properties (mean mass and dispersion of the final GCMF,
fraction of surviving clusters, radial gradient of the GCMF parameters) on the
structure of the host galaxy and on the slope of the initial GCMF. For a
subsample of host galaxies with values of effective masses and radii equal to
those determined using observational data for a number of giant, normal and
dwarf galaxies our results show that the relation between the final GCMF
properties and those of the host galaxies as well as the dependence of the
final GCMF parameters on the galactocentric distance within individual galaxies
differ from those observed in old GCS: the values of the final GCS mean mass
are in general smaller (4.2 < log M_final < 5.0) than those observed and the
galaxy-to-galaxy dispersion of logM_final is larger than that reported by
observational analyses. The results are compared with those of a companion
paper in which we investigated the evolution of GCS with a log-normal initial
GCMF and in which the final GCS properties were perfectly consistent with
observations.

</DOC>
<DOC>
<DOCNO> 84278 </DOCNO>
Hamiltonian formulation of general relativity in the teleparallel


  We establish the Hamiltonian formulation of the teleparallel equivalent of
general relativity, without fixing the time gauge condition, by rigorously
performing the Legendre transform. The time gauge condition, previously
considered, restricts the teleparallel geometry to the three-dimensional
spacelike hypersurface. Geometrically, the teleparallel geometry is now
extended to the four-dimensional space-time. The resulting Hamiltonian
formulation is different from the standard ADM formulation in many aspects, the
main one being that the dynamics is now governed by the Hamiltonian constraint
H_0 and a set of primary constraints. The vector constraint H_i is derived from
the Hamiltonian constraint. The vanishing of the latter implies the vanishing
of the vector constraint.

</DOC>
<DOC>
<DOCNO> 101551 </DOCNO>
Relative Gromov-Witten invariants and the mirror formula


  Let X be a smooth complex projective variety, and let Y in X be a smooth very
ample hypersurface such that -K_Y is nef. Using the technique of relative
Gromov-Witten invariants, we give a new short and geometric proof of (a version
of) the "mirror formula", i.e. we show that the generating function of the
genus zero 1-point Gromov-Witten invariants of Y can be obtained from that of X
by a certain change of variables (the so-called "mirror transformation").
Moreover, we use the same techniques to give a similar expression for the
(virtual) numbers of degree-d plane rational curves meeting a smooth cubic at
one point with multiplicity 3d, which play a role in local mirror symmetry.

</DOC>
<DOC>
<DOCNO> 100535 </DOCNO>
Algebras with a compatible uniformity


  Given a variety of algebras V, we study categories of algebras in V with a
compatible structure of uniform space. The lattice of compatible uniformities
of an algebra, Unif A, can be considered a generalization of the lattice of
congruences Con A. Mal'cev properties of V influence the structure of Unif A,
much as they do that of Con A. The category V[CHUnif] of complete, Hausdorff
uniform algebras in the variety V is particularly interesting; it has a natural
factorization system extending the usual (onto, one-one) factorization system
of V.

</DOC>
<DOC>
<DOCNO> 102409 </DOCNO>
Spectral Properties of a Binomial Matrix


  In this paper we study some further properties of the matrix with entries
binom{i-1}{n-j}. We find the generating function for each row and column, and
we find the eigenvalues and eigenvectors of this matrix. We also find the
spectral properties of this matrix modulo 3 and 5.

</DOC>
<DOC>
<DOCNO> 12023 </DOCNO>
Spin-Polaron approach to the Fermi surface evolution in the normal state


  A semi-phenomenological approach to describe the evolution of Fermi surface
(FS) and electronic structure with doping is presented which is based on the
spin-fermion model. The doping is simulated by a frustration term in the spin
Hamiltonian and the complex internal structure of the spin-polaron
quasiparticle is taken into account by a superposition of spin-polaron states
with different radii. By calculating the spectrum, the spectral weights and the
FS we find a rather drastic change of the electronic structure with doping
which explains many photoemission data, i.e. the isotropic band bottom and the
remnant FS of undoped cuprates, the large FS and the extended saddle point of
optimally doped compounds and the pseudogap in the underdoped samples.

</DOC>
<DOC>
<DOCNO> 69489 </DOCNO>
Neutron beta decay and the current determination of Vud


  Measurements of neutron beta decay observables required to determine
$|V_{ud}|$ are reaching the 0.1% accuracy. In this paper we review the
calculation of the decay rate of this process, discuss its relevant
uncertainties, and obtain an expression that is precise at the $10^{-4}$ level.
Our analysis clearly shows the necessity of measurements of $\lambda$, the
ratio of axial/vector couplings. The current situation in neutron beta decay is
that one cannot yet quote a single consistent value for $|V_{ud}|$ from it. We
also discuss the region of parameter space in the $|V_{ud}|$--$\lambda$ plane
where new physics effects should lie, if they contribute to neutron beta decay.

</DOC>
<DOC>
<DOCNO> 102613 </DOCNO>
A generalised inductive approach to the lace expansion


  The lace expansion is a powerful tool for analysing the critical behaviour of
self-avoiding walks and percolation. It gives rise to a recursion relation
which we abstract and study using an adaptation of the inductive method
introduced by den Hollander and the authors. We give conditions under which the
solution to the recursion relation behaves as a Gaussian, both in Fourier space
and in terms of a local central limit theorem. These conditions are shown
elsewhere to hold for sufficiently spread-out models of networks of
self-avoiding walks in dimensions $d>4$, and for critical oriented percolation
in dimensions $d+1>5$, providing a unified approach and an essential ingredient
for a detailed analysis of the branching behaviour of these models.

</DOC>
<DOC>
<DOCNO> 99306 </DOCNO>
The Bianchi-Darboux transform of L-isothermic surfaces


  We study an analogue of the classical Bianchi-Darboux transformation for
L-isothermic surfaces in Laguerre geometry, the Bianchi-Darboux transformation.
We show how to construct the Bianchi-Darboux transforms of an L-isothermic
surface by solving an integrable linear differential system. We then establish
a permutability theorem for iterated Bianchi-Darboux transforms.

</DOC>
<DOC>
<DOCNO> 119787 </DOCNO>
Neutrino, Neutron, and Cosmic Ray Production in the External Shock Model


  The hypothesis that ultra-high energy (> 10^{19} eV) cosmic rays (UHECRs) are
accelerated by gamma-ray burst (GRB) blast waves is assumed to be correct.
Implications of this assumption are then derived for the external shock model
of gamma-ray bursts. The evolving synchrotron radiation spectrum in GRB blast
waves provides target photons for the photomeson production of neutrinos and
neutrons. Lower limits to the diffuse high-energy GRB neutrino background and
the distribution of high-energy GRB neutrino events are derived. GRBs provide
an intense flux of high-energy neutrons, with neutron-production efficiencies
exceeding ~ 1% of the total energy release. The radiative characteristics of
the neutron \beta-decay electrons are solved in a special case. Galaxies with
GRB activity should be surrounded by radiation halos of ~ 100 kpc extent from
the outflowing neutrons, consisting of a nonthermal optical/X-ray synchrotron
component and a high-energy gamma-ray Compton component from upscattered
microwave background radiation. The luminosity of sources of GRBs in the Milky
Way must exceed ~ 2x10^{39} ergs/s to account for UHECR generation by GRBs.
This figure is in accord with the burst rate implied by statistical modeling of
GRBs in the external shock model, and represents ~5% of the CR power in the
Galaxy. Relativistic fireball transients (FTs), which includes GRBs as a
subclass, could account for a dominant contribution to CR production at
energies << 10^{15} eV. This hypothesis for CR origin surmounts several
observational difficulties in the conventional scenario that CRs originate from
SNe that are unrelated to GRBs. FTs probably come from the >~ 60 M_\odot regime
of stars that end their lives as Type Ib/c SNe, and leave \approx 10^6-10^7
medium mass (>~10-30 M_\odot) black holes in the galaxy. (abridged)

</DOC>
<DOC>
<DOCNO> 122907 </DOCNO>
New constraints on the cosmic mid-infrared background using TeV


  Very high energy gamma-ray data obtained by CAT and HEGRA from active
galactic nucleus Mkn 501 are used to constrain the cosmic Mid-Infrared
background. While the entire infrared and submillimeter spectrum shape based on
models has been fixed and the density scaled as a whole in previous studies,
recent measures on the low and high energy infrared background are extensively
used in this paper. In this original approach, the infrared distribution is
only varied in the unexplored 3.5-100 microns region. With conservative
hypothesis on the intrinsic spectra of Mkn 501, an upper limit of 4.7
nW.m-2.sr-1 between 5 and 15 microns is derived, which is very close to the
lower limit inferred from deep ISOCAM cosmological surveys at 15 microns. This
result is shown to be independent of the exact density of the lambda < 3.5
microns and lambda > 100 microns infrared distribution within the uncertainties
of the measurements. Moreover, the study presented here rules out a complete
extragalactic origin for the 60 microns excess found by Finkbeiner et al.
(2000).

</DOC>
<DOC>
<DOCNO> 40256 </DOCNO>
Model Independent Extractions of |V_{ub}| from Inclusive B Decays


  We discuss the possibility of extracting |V_{ub}| from various spectra of
inclusive B decays, without large systematic errors which usually arise from
having to model the Fermi motion of the heavy quark. This strategy can be
applied to the electron energy spectrum, as well as the hadronic mass spectrum.
Modulo violation of local hadron-parton duality, the theoretical error in the
extraction is estimated to be less than 10%.

</DOC>
<DOC>
<DOCNO> 118845 </DOCNO>
Detection of a Far IR Excess with DIRBE at 60 and 100 Microns


  From analysis of the DIRBE weekly averaged sky maps, we have detected
substantial flux in the 60 and 100 micron channels in excess of expected
zodiacal and Galactic emission. Two methods are used to separate zodiacal light
from more distant emission. Method I makes use of the time-dependence of the
North-South annual variation observed at the ecliptic poles. This method is
robust against errors in the inter-planetary dust (IPD) model, but does not
demonstrate isotropy of the background. Method II measures the ecliptic
latitude dependence of the dust over a range of ecliptic latitudes at solar
elongation e=90 degrees. This allows the excess to be determined in each week
of the DIRBE mission for high redundancy, but the results depend weakly on the
IPD model. Both methods give consistent results at 60 and 100 microns. The
observed signal is consistent with an isotropic background at the level \nu
I_\nu = 28.1 +- 1.8 +- 7(syst) nW/m^2/sr at 60 microns and 24.6 +- 2.5 +- 8
nW/m^2/sr at 100 microns.
  The IR excess detected at 140 and 240 microns by these methods agrees with
previous measurements, which are thought to be the cosmic infra-red background
(CIB). The detections at 60 and 100 microns are new. While this new excess is
not necessarily the CIB, we have ruled out all known sources of emission in the
solar system and Galaxy. We therefore tentatively interpret this signal as the
CIB and consider the implications of such energy production from the viewpoint
of star formation efficiency and black hole accretion efficiency. However, the
IR excess exceeds limits on the CIB derived from the inferred opacity of the
IGM to observed TeV photons, thus casting doubt on this interpretation. There
is currently no satisfactory explanation for the 60-100 micron excess.

</DOC>
<DOC>
<DOCNO> 101514 </DOCNO>
Dual elliptic structures on CP2


  We consider an almost complex structure J on CP2, or more generally an
elliptic structure E which is tamed by the standard symplectic structure. An
E-curve is a surface tangent to E (this generalizes the notion of
J(holomorphic)-curve), and an E-line is an E-curve of degree 1. We prove that
the space of E-lines is again a CP2 with a tame elliptic structure E^*, and
that each E-curve has an associated dual E^*-curve. This implies that the
E-curves, and in particular the J-curves, satisfy the Pl\"ucker formulas, which
restricts their possible sets of singularities.

</DOC>
<DOC>
<DOCNO> 70395 </DOCNO>
The legacy of HERA - the first decade


  The ep HERA collider started operation in summer of 1992. This talk
summarizes some of the highlights of physics results obtained since then and
discusses their impact on our understanding of Quantum Chromodynamics (QCD).

</DOC>
<DOC>
<DOCNO> 84405 </DOCNO>
Closed Lightlike Curves in Non-linear Electrodynamics


  We show that non-linear electrodynamics may induce a photon to follow a
closed path in spacetime. We exhibit a specific case in which such closed
lightlike curve (CLC) appears

</DOC>
<DOC>
<DOCNO> 9920 </DOCNO>
Non-monotonous crossover between capillary condensation and interface


  Within self-consistent field theory we study the phase behaviour of a
symmetric binary AB polymer blend confined into a thin film. The film surfaces
interact with the monomers via short range potentials. One surface attracts the
A component and the corresponding semi-infinite system exhibits a first order
wetting transition. The surface interaction of the opposite surface is varied
as to study the crossover from capillary condensation for symmetric surface
fields to the interface localisation/delocalisation transition for
antisymmetric surface fields. In the former case the phase diagram has a single
critical point close to the bulk critical point. In the latter case the phase
diagram exhibits two critical points which correspond to the prewetting
critical points of the semi-infinite system. The crossover between these
qualitatively different limiting behaviours occurs gradually, however, the
critical temperature and the critical composition exhibit a non-monotonic
dependence on the surface field.

</DOC>
<DOC>
<DOCNO> 152292 </DOCNO>
T-duality and Actions for Non-Commutative D-Branes


  We show how the T-duality is realized for D-branes with noncommutative
world-volume coordinates. We discuss D-branes wrapped on tori and the result is
that the recently found noncommutative actions form a consistent collection due
to the T-duality mapping between noncommutative D-branes and rotated
commutative D-branes on deformed tori.

</DOC>
<DOC>
<DOCNO> 121012 </DOCNO>
Gas Flow and Star Formation in the `Antennae' Galaxies NGC 4038/9


  The prominent interacting galaxy pair NGC 4038/9 contains many active
star-forming regions and is continuously forming new star clusters. We present
a self-consistent n-body model for this system which includes an SPH gas
component. The model qualitatively explains the apparent concentration of gas
in the so-called overlap region between the two nuclei as a bridge of gas
connecting the two galaxies. Projected on the sky, the bridge appears as a
dense spot of gas. We discuss some implications for the evolution of
Ultra-luminous infrared galaxies.

</DOC>
<DOC>
<DOCNO> 84840 </DOCNO>
Quantum Gravity in D=5 Dimensions


  We propose a topological Chern-Simons term in D=5 dimensions coupled to
Einstein Hilbert theory. Hartree approximation for topological Lagrangian and
the Chern-Simons term in D=3 is considered. An effective model of Quantum
Gravity in D=5 dimensions is presented here. The analysis of residues is
considered and the unitarity is guaranteed at tree level. The propagator is
ghost and tachyon free.

</DOC>
<DOC>
<DOCNO> 69894 </DOCNO>
Topology in the Bulk: Gauge Field Solitons in Extra Dimensions


  Certain static soliton configurations of gauge fields in 4+1 dimensions
correspond to the instanton in 4-Euclidean dimensions ``turned on its side,''
becoming a monopole in 4+1. The periodic instanton solution can be used with
the method of images to construct solutions satisfying D-brane boundary
conditions. The $\theta$-term on the brane becomes a topological current
source, yielding an emission amplitude for monopoles into the bulk. Instantons
have a novel reinterpretation in terms of monopole exchange between branes.

</DOC>
<DOC>
<DOCNO> 122647 </DOCNO>
Gamma-ray Burst Afterglow with Continuous Energy Injection: Signature of


  We investigate the consequences of a continuously injecting central engine on
the gamma-ray burst afterglow emission, focusing more specifically on a
highly-magnetized millisecond pulsar engine. For initial pulsar parameters
within a certain region of the parameter space, the afterglow lightcurves are
predicted to show a distinctive achromatic bump feature, the onset and duration
of which range from minutes to months, depending on the pulsar and the fireball
parameters. The detection of or upper limits on such features would provide
constraints on the burst progenitor and on magnetar-like central engine models.
An achromatic bump such as that in GRB 000301C afterglow may be caused by a
millisecond pulsar with P0=3.4 millisecond and Bp=2.7e14 Gauss.

</DOC>
<DOC>
<DOCNO> 8959 </DOCNO>
The role of Berry phase in the spectrum of order parameter dynamics: a


  We formulate the dynamics of local order parameters by extending the recently
developed adiabatic spinwave theory involving the Berry curvature, and derive a
formula showing explicitly the role of the Berry phase in determining the
spectral form of the low-lying collective modes. For antiferromagnetic spin
chains, the Berry phase becomes a topological invariant known as the Chern
number. Our theory predicts the existence of the Haldane gap for a
topologically trivial ground state, and a linear dispersion of low-lying
excitations for a non-trivial ground state.

</DOC>
<DOC>
<DOCNO> 8725 </DOCNO>
Generic Jumps of Fredholm Indices and the Quantum Hall Effect


  We describe the generic behavior of Fredholm indices in the space of Toeplitz
operators. We relate this behavior to certain conjectures and open problems
that arise in the context of the Quantum Hall Effect.

</DOC>
<DOC>
<DOCNO> 11648 </DOCNO>
Use of optically detected magnetic resonance to correlate germanium


  The relationship between paramagnetic defect centers and UV absorption bands
simultaneously generated by ionizing radiation in Ge-doped SiO2 glass is
investigated using magneto-optical techniques. A sample of 7.0 mol% Ge-doped
SiO2 was exposed to X-ray radiation, which resulted in the formation of
absorption bands centered at 4.4 eV and 5.7 eV as well as electron spin
resonance (ESR) signals attributed to the Ge(1) and Ge(2) defects. To isolate
paramagnetic contributions to the induced optical absorption, the magnetic
circular dichroism absorption (MCDA) spectrum was measured at several different
temperatures over the range 2.00-6.21 eV. The optically detected magnetic
resonance (ODMR) spectrum was then obtained at 4.42 eV via microwave-induced
changes in the MCDA signals in order to unambiguously correlate this optical
transition with a particular ESR signal. The ODMR data indicates that the Ge(1)
center is responsible for this absorption band, providing the first unequivocal
correlation of ESR and optical properties for this defect. In addition,
evidence of a weakly absorbing paramagnetic defect was found at 5.65 eV that
appears to be related to the Ge(2) center.

</DOC>
<DOC>
<DOCNO> 10253 </DOCNO>
Pseudogap and Superconducting Fluctuations in High-Tc Cuprates


  We analyze pseudogap phenomena widely observed in the underdoped cuprates. We
assume the existence of a strong d-wave pairing force competing with
antiferromagnetic(AFM) fluctuations and the formation of flat and damped
dispersion around the $(\pi,0)$ and $(0,\pi)$ region as two important elements
caused by the proximity from the Mott insulator. Using the mode-mode coupling
theory for the d-wave superconducting(dSC) and AFM fluctuations, we reproduce
basic properties of the pseudogap seen in the magnetic resonance, neutron
scattering, angle resolved photoemission and tunneling measurements in the
cuprates. Then minimal requirements to understand the pseudogap phenomena are
clarified as the above two elements. A strong competition of the pairing with
the antiferromagnetic fluctuations suppresses the transition temperature
thereby generates the pseudogap in the underdoped region while the weakness of
the AFM fluctuations leads to the absence of the pseudogap at the optimal
doping concentration.}

</DOC>
<DOC>
<DOCNO> 121271 </DOCNO>
Disks irradiated by beamed radiation from compact objects


  We examine the reprocessing of X-ray radiation from compact objects by
accretion disks when the X-ray emission from the star is highly beamed. The
reprocessed flux for various degrees of beaming and inclinations of the beam
axis with respect to the disk is determined. We find that, in the case where
the beam is produced by a non-relativistic object, the intensity of the emitted
spectrum is highly suppressed if the beam is pointing away from the disk.
However, for beams produced by compact objects, general relativistic effects
cause only a small reduction in the reradiated flux even for very narrow beams
oriented perpendicularly to the disk. This is especially relevant in
constraining models for the anomalous X-ray pulsars, whose X-ray emission is
highly beamed. We further discuss other factors that can influence the emission
from disks around neutron stars.

</DOC>
<DOC>
<DOCNO> 9327 </DOCNO>
Individual energy level distributions for one-dimensional diagonal and


  We study the distribution of the $n$-th energy level for two different
one-dimensional random potentials. This distribution is shown to be related to
the distribution of the distance between two consecutive nodes of the wave
function.
  We first consider the case of a white noise potential and study the
distributions of energy level both in the positive and the negative part of the
spectrum. It is demonstrated that, in the limit of a large system
($L\to\infty$), the distribution of the $n$-th energy level is given by a
scaling law which is shown to be related to the extreme value statistics of a
set of independent variables.
  In the second part we consider the case of a supersymmetric random
Hamiltonian (potential $V(x)=\phi(x)^2+\phi'(x)$). We study first the case of
$\phi(x)$ being a white noise with zero mean. It is in particular shown that
the ground state energy, which behaves on average like $\exp{-L^{1/3}}$ in
agreement with previous work, is not a self averaging quantity in the limit
$L\to\infty$ as is seen in the case of diagonal disorder. Then we consider the
case when $\phi(x)$ has a non zero mean value.

</DOC>
<DOC>
<DOCNO> 71706 </DOCNO>
Intersecting Brane Worlds


  It is known that chiral fermions naturally appear at certain intersections of
branes at angles. Motivated by this fact, we propose a string scenario in which
different standard model gauge interactions propagate on different
(intersecting) brane worlds, partially wrapped in the extra dimensions. Quarks
and leptons live at brane intersections, and are thus located at different
positions in the extra dimensions. Replication of families follows naturally
from the fact that the branes generically intersect at several points. Gauge
and Yukawa couplings can be computed in terms of the compactification radii.
Hierarchical Yukawa couplings appear naturally, since amplitudes involving
three different intersections are proportional to exp{-A_{ijk}}, where A_{ijk}
is the area of a string world-sheet extending among the intersections. The
models are non-supersymmetric but the string scale may be lowered down to 1-10
TeV. The proton is however stable due to a set of discrete symmetries arising
from world-sheet selection rules, exact to all orders in perturbation theory.
The scenario has some distinctive features like the presence of KK, winding and
other new excited states (`gonions'), with masses below the string scale and
accessible to accelerators. The models contain scalar tachyons with the quantum
numbers of standard SU(2) x U(1) Higgs doublets, and we propose that they
induce electroweak symmetry breaking in a somewhat novel way. Specific string
models with D4-branes wrapping on T^2 x (T^2)^2/Z_N, leading to three-family
semirealistic spectra, are presented, in which the above properties are
exemplified.

</DOC>
<DOC>
<DOCNO> 11051 </DOCNO>
Nesting Induced Precursor Effects: a Renormalization Group Approach


  We develop a controlled weak coupling renormalization group (RG) approach to
itinerant electrons. Within this formalism we rederive the phase diagram for
two-dimensional (2D) non-nested systems. Then we study how nesting modifies
this phase diagram. We show that competition between p-p and p-h channels,
leads to the manifestation of unstable precursor fixed points in the RG flow.
This effect should be experimentally measurable, and may be relevant for an
explanation of pseudogaps in the high temperature superconductors (HTC), as a
crossover phenomenon.

</DOC>
<DOC>
<DOCNO> 102703 </DOCNO>
On moduli spaces of symplectic forms


  We prove that, for any n, there are simply-connected four-manifolds which
admit n-tuples of symplectic forms whose first Chern classes have pairwise
different divisibilities in integral cohomology. It follows that the moduli
space of symplectic forms modulo diffeomorphisms on such a manifold has at
least n connected components.

</DOC>
<DOC>
<DOCNO> 99598 </DOCNO>
Entropy in type I algebras


  It is shown that if (M,phi,alpha) is a W*-dynamical system with M a type I
von Neumann algebra then the entropy of alpha w.r.t. phi equals the entropy of
the restriction of alpha to the center of M. If furthermore (N,psi,beta) is a
W*-dynamical system with N injective then the entropy of the tensor product
system is the sum of the entropies.

</DOC>
<DOC>
<DOCNO> 100549 </DOCNO>
*-semigroup endomorphisms of B(H)


  Let H be a complex infinite dimensional Hilbert space. We describe the form
of all *-semigroup endomorphisms $\phi$ of B(H) which are uniformly continuous
on every commutative C*-subalgebra. In particular, we obtain that if $\phi$
satisfies $\phi(0)=0$, then $\phi$ is additive.

</DOC>
<DOC>
<DOCNO> 40198 </DOCNO>
A measurement of the B^0-anti-B^0 oscillation frequency and


  B^0-anti-B^0 flavor oscillations are studied in e^+e^- annihilation data
collected with the BABAR detector at center-of-mass energies near the Y(4S)
resonance. One B is reconstructed in a hadronic or semileptonic decay mode, and
the flavor of the other B in the event is determined with a tagging algorithm
that exploits the relation between the flavor of the heavy quark and the
charges of its decay products. Tagging performance is characterized by an
efficiency e_i and a probability for mis-identification, w_i, for each tagging
category. We report a determination of the wrong-tag probabilities, w_i, and a
preliminary result for the time-dependent B^0-anti-B^0 oscillation frequency,
Delta_md = 0.512+/-0.017+/-0.022 hbar-ps^{-1}.

</DOC>
<DOC>
<DOCNO> 151417 </DOCNO>
Nonperturbative effects in deformation quantization


  The Cattaneo-Felder path integral form of the perturbative Kontsevich
deformation quantization formula is used to explicitly demonstrate the
existence of nonperturbative corrections to na\"\i ve deformation quantization.

</DOC>
<DOC>
<DOCNO> 67756 </DOCNO>
Charge symmetry violation in the parton distributions of the nucleon


  We point out that charge symmetry violation in both the valence and sea quark
distributions of the nucleon has a non-perturbative source. We calculate this
non-perturbative charge symmetry violation using the meson cloud model, which
has earlier been successfully applied to both the study of SU(2) flavour
asymmetry in the nucleon sea and quark-antiquark asymmetry in the nucleon. We
find that the charge symmetry violation in the valence quark distribution is
well below 1%, which is consistent with most low energy tests but significantly
smaller than the quark model prediction about 5%-10%. Our prediction for the
charge symmetry violation in the sea quark distribution is also much smaller
than the quark model calculation.

</DOC>
<DOC>
<DOCNO> 99923 </DOCNO>
Residual finiteness for complexified real line arrangements


  A group is said to be residually finite if it injects into its pro-finite
completion. Toledo, Catanese-Kollar, and others have shown that the fundamental
group of a Kahler manifold need not be residually finite. In this paper, we
find a family of complex affine algebraic surfaces which have residually finite
fundamental group. In particular, we show that complements of complexified real
line arrangements in the complex plane have residually finite fundamental
group. To do this we introduce the notion of "unknotted" complex plane curves,
and describe the homotopy type of the complement in terms of the boundary
manifold of the curve. The main result comes from extending a theorem of
Hempel, and giving a local criterion for "graph quotients" of graphs of groups
to be residually finite.

</DOC>
<DOC>
<DOCNO> 117571 </DOCNO>
Identification of the Coronal Sources of the Fast Solar Wind


  The present spectroscopic study of the ultraviolet coronal emission in a
polar hole, detected on April 6-9, 1996 with the Ultraviolet Coronagraph
Spectrometer aboard the SOHO spacecraft, identifies the inter-plume lanes and
background coronal hole regions as the channels where the fast solar wind is
preferentially accelerated. In inter-plume lanes, at heliocentric distance 1.7
\rsun, the corona expands at a rate between 105 km/s and 150 km/s, that is,
much faster than in plumes where the outflow velocity is between 0 km/s and 65
km/s. The wind velocity is inferred from the Doppler dimming of the O VI
$\lambda\lambda$ 1032, 1037 \AA lines, within a range of values, whose lower
and upper limit corresponds to anisotropic and isotropic velocity distribution
of the oxygen coronal ions, respectively.

</DOC>
<DOC>
<DOCNO> 117363 </DOCNO>
Morphological evolution of X-ray clusters using hydrodynamical


  A large set of TREESPH simulations is used to test the global morphology of
galaxy clusters and its evolution against X-ray data. A powerful method to
investigate substructures in galaxy clusters are the power ratios introduced by
Buote & Tsai. We consider three flat cosmological models: CDM,
LCDM($\Omega_\Lambda = 0.7$) and CHDM($\Omega_h = 0.2$, 1 massive $\nu$), all
normalized so to fit the observed number of clusters. For each model we built
40 clusters, using a TREESPH code, and performed a statistical comparison with
a data sample including nearby clusters observed with ROSAT PSPC instrument.
The comparison disfavors the LCDM model, as clusters appear too relaxed, while
CDM and CHDM clusters, in which a higher degree of complexity occurs, seem to
be closer to observations. A better fit of data can be expected for some
different DM mix. If DM distributions are used instead of baryons, we find
substructures more pronounced than in gas and models have a different score.
Using hydrodynamical simulations is therefore essential to our aims.

</DOC>
<DOC>
<DOCNO> 40511 </DOCNO>
Charmless Hadronic B Decays at BABAR


  We present preliminary results of several searches for rare charmless
hadronic decays of the B meson using data collected by the BABAR detector at
the Stanford Linear Accelerator Center's PEP-II storage ring. We search for the
decays h^+h^-, h^+h^-h^+, h^+h^-pi^0, X^0h^+, and X^0 K_S^0, where h = pi or K,
and X^0 = eta^prime or omega. In a sample of 8.8 million B-anti-B decays we
measure the branching fractions: BF(B^0 --> pi^+pi^-) =
(9.3^{+2.6}_{-2.3}^{+1.2}_{-1.4}) x 10^{-6}, BF(B^0 --> K^+pi^-) =
(12.5^{+3.0}_{-2.6}^{+1.3}_{-1.7}) x 10^{-6}, BF(B^0 --> rho^-pi^+) = (49 +/-
13^{+6}_{-5}) x 10^{-6}$, and BF(B^+ --> eta^prime K^+) = (62 +/- 18 +/- 8) x
10^{-6}$. We calculate upper limits for the modes without a significant signal.

</DOC>
<DOC>
<DOCNO> 102301 </DOCNO>
Factorisation faible des applications birationnelles [d'apr\`es


  Dans cet expos\'e, nous expliquons le r\'esultat suivant d\'emontr\'e
r\'ecemment par Abramovich, Karu, Matsuki et W{\l}odarczyk : toute application
birationnelle entre deux vari\'et\'es alg\'ebriques compl\`etes et lisses sur
un corps alg\'ebriquement clos de caract\'eristique nulle se factorise en une
suite finie d'\'eclatements et de contractions de centres lisses. Ce r\'esultat
n'aurait sans doute pas vu le jour sans la d\'emonstration de son analogue dans
le cadre de la g\'eom\'etrie torique par Morelli et W{\l}odarczyk au milieu des
ann\'ees 90. La d\'emonstration donn\'ee par Abramovich, Karu, Matsuki et
W{\l}odarczyk est une r\'eduction au cas torique, nous en donnons les grandes
\'etapes.

</DOC>
<DOC>
<DOCNO> 123266 </DOCNO>
The Cyclotron Fundamental Exposed in the High-Field Magnetic Variable


  High-quality phase-resolved optical spectropolarimetry is presented for the
magnetic cataclysmic variable V884 Her. The overall circular polarization
during active accretion states is low and only slightly variable in the range
5000-8000A. However, the polarization is highly structured with wavelength,
showing very broad polarization humps, narrow features that are associated with
weak absorption lines in the total spectral flux, and sharp reversals across
each major emission line. The polarization reversals arise from Zeeman
splitting in the funnel gas in a longitudinal magnetic field B~30kG. The set of
narrow, polarized absorption features matches the Zeeman pattern of hydrogen
for a nearly uniform magnetic field of B=150MG, indicating that the features
are "halo" absorption lines formed in a relatively cool reversing layer above
the shock. With this identification, the broad polarization humps centered near
7150A and below 4000A are assigned to cyclotron emission from the fundamental
and first harmonic (n=2), respectively. V884 Her is only the second AM Her
system known with a field exceeding 100MG, and the first case in which the
cyclotron fundamental has been directly observed from a magnetic white dwarf.

</DOC>
<DOC>
<DOCNO> 40222 </DOCNO>
In Celebration of the Fixed Target Program with the Tevatron


  This document is an abridgement of the commemorative book prepared on the
occasion of the symposium "In Celebration of the Fixed Target Program with the
Tevatron" held at Fermilab on June 2, 2000. The full text with graphics
contains, in addition to the material here, a section for each experiment
including a "plain text" description, lists of all physics publications, lists
of all degree recipients and a photo from the archives. The full text is
available on the web at: http://conferences.fnal.gov/tevft/book/

</DOC>
<DOC>
<DOCNO> 68045 </DOCNO>
The Quantum Boltzmann Equation in a Nontrivial Background


  This talk is a status report on our study of quantum transport equations
relevant for baryogenesis computations. Our main finding is that, as a
consequence of localization in space, the quasiparticle picture of the plasma
dynamics breaks down at first non-trivial order in gradient expansion. While in
this talk we focus on bosons, we expect that a similar picture holds for
fermions. We then argue that the quasiparticle picture is recovered in the
adiabatic limit of frequent scattering.

</DOC>
<DOC>
<DOCNO> 12103 </DOCNO>
Large-amplitude oscillation dynamics and domain suppression in a


  We analyze the current dynamics of a superlattice Bloch oscillator under
conditions where, in addition to the dc bias field causing a negative
differential ac conductivity, a similarly strong ac field is present, at a
frequency somewhat below the Bloch frequency associated with the dc field. The
differential conductivity at the ac drive frequency is then negative, but,
because of the strong non-linearities of the system, the dc differential
conductivity is modified by the ac field. For a sufficiently strong ac field,
there will be a dc bias range inside which the dc differential conductivity has
turned positive, while the ac conductivity remains negative. The phenomenon
should lend itself to the suppression of the domain-like space charge
instabilities that are normally associated with a negative dc differential
conductivity.

</DOC>
<DOC>
<DOCNO> 101080 </DOCNO>
Nonfiliform characteristically nilpotent Lie algebras


  We construct large families of characteristically nilpotent Lie algebras by
considering deformations of the Lie algebra g_{m,m-1}^{4} of type Q_{n},and
which arises as a central extension fo the filiform Lie algebra L_{n}. By
studying the graded cohomology spaces we obtain that the sill algebras are
isomorphic to the nilradicals of solvable, complete Lie algebra laws. For
extremal cocycles these laws are also rigid. Considering supplementary cocycles
we construcy, for dimensions n>8, nonfiliform characteristically nilpotent Lie
algebras and show that for certain deformations these are compatible with
central extensions.

</DOC>
<DOC>
<DOCNO> 13085 </DOCNO>
Macroscopic quantum tunneling of the Bose-Einstein condensate trapped in


  We investigate the macroscopic quantum tunneling of the attractive
Bose-Einstein condensate. Within the effective Lagrangian framework, we find
bounce solutions and explicitly calculate the decay rate of the condensate
trapped in a cylindrically symmetric potential. In particular, in the case
where the number of condensed bosons is slightly below a certain critical
number, we present a detailed analysis of the bounce solutions and discuss the
approximations employed in our calculations. The effects of finite temperatures
and the shape of the trapping potential are evaluated.

</DOC>
<DOC>
<DOCNO> 9177 </DOCNO>
Analysis of Dislocation Mechanism for Melting of Elements


  The melting of elemental solids is modelled as a dislocation-mediated
transition on a lattice. Statistical mechanics of linear defects is used to
obtain a new relation between melting temperature, crystal structure, atomic
volume, and shear modulus that is accurate to 17% for at least half of the
Periodic Table.

</DOC>
<DOC>
<DOCNO> 11394 </DOCNO>
Collective dynamics of liquid aluminum probed by Inelastic X-ray


  An inelastic X-ray scattering experiment has been performed in liquid
aluminum with the purpose of studying the collective excitations at wavevectors
below the first sharp diffraction peak. The high instrumental resolution (up to
1.5 meV) allows an accurate investigation of the dynamical processes in this
liquid metal on the basis of a generalized hydrodynamics framework. The
outcoming results confirm the presence of a viscosity relaxation scenario ruled
by a two timescale mechanism, as recently found in liquid lithium.

</DOC>
<DOC>
<DOCNO> 40641 </DOCNO>
Problems of multi-TeV photon colliders


  A high energy photon collider (gamma-gamma, gamma-electron) based on backward
Compton scattering of laser light is a very natural supplement to e+e- a linear
collider and can significantly enrich the physics program. The region below
about one 0.5-1 TeV is very convenient from a technical point of view: wave
length of the laser should be about 1 micron, i.e. in the region of most
powerful solid state lasers, collision effects do not restrict the gamma-gamma
luminosity. In the multi-TeV energy region the situation is more complicated:
the optimum laser wave length increases in proportionally with the energy, the
required flash energy also increases due to nonlinear effects in the Compton
scattering; bunch trains are shorter (for warm high gradient linacs), this
leads to higher backgrounds; the collision effects (coherent pair e+e- pair
creation) restrict the luminosity. These problems and possible solutions are
discussed in this paper. A method of laser focusing is considered which allows
the decrease of the required laser flash energy and the practical elimination
of the problem of nonlinear effects in Compton scattering; a way to reduce
collision effects and obtain ultimate gamma-gamma luminosities at multi-TeV
photon colliders is suggested.

</DOC>
<DOC>
<DOCNO> 70576 </DOCNO>
5-Dimensional Warped Cosmological Solutions With Radius Stabilization by


  We present the 5-dimensional cosmological solutions in the Randall-Sundrum
warped compactification scenario, using the Goldberger-Wise mechanism to
stabilize the size of the extra dimension. Matter on the Planck and TeV branes
is treated perturbatively, to first order. The back-reaction of the scalar
field on the metric is taken into account. We identify the appropriate
gauge-invariant degrees of freedom, and show that the perturbations in the bulk
scalar can be gauged away. We confirm previous, less exact computations of the
shift in the radius of the extra dimension induced by matter. We point out that
the physical mass scales on the TeV brane may have changed significantly since
the electroweak epoch due to cosmological expansion, independently of the
details of radius stabilization.

</DOC>
<DOC>
<DOCNO> 71567 </DOCNO>
B_s -> \tau^+ \tau^- decay in the general two Higgs Doublet model


  We study the exclusive decay B_s -> \tau^+ \tau^-$ in the general two Higgs
doublet model. We analyse the dependencies of the branching ratio on the model
parameters, including the leading order QCD corrections. We found that there is
an enhancement in the branching ratio, especially for
r_{tb}=\frac{\bar{\xi}_{N,tt}^U}{\bar{\xi}_{N,bb}^D}>1 case. Further, the
neutral Higgs effects are detectable for large values of the parameter
\bar{\xi}_{N,\tau\tau}^D.

</DOC>
<DOC>
<DOCNO> 10284 </DOCNO>
First order transition from ferro- to antiferromagnetism in CeFe$_2$


  We present results of ac susceptibility measurements highlighting the
presence of thermal hysteresis and phase coexistence across the ferro-to
antiferromagnetic transition in various CeFe$_2$ based pseudobinary systems.
These results indicate that the ferro-to antiferromagnetic transition in these
systems is first order in nature.

</DOC>
<DOC>
<DOCNO> 40451 </DOCNO>
The Time Dependence of B0->f Decays


  We calculate the time dependence of B0->f decays (and analogously D0->f
decays) and use this result to obtain expressions for the time dependence of:
an untagged sample (B0->f and Bbar->f decays combined), a sample containing
charge-conjugate final states (B0->f and B0->fbar decays combined), and a
sample containing all four decay modes together. For simplicity we assume CP
violating effects are negligible.

</DOC>
<DOC>
<DOCNO> 119642 </DOCNO>
Relativity as the quantum mechanics of space-time measurements


  Can a simple microscopic model of space and time demonstrate Special
Relativity as the macroscopic (aggregate) behavior of an ensemble ? The
question will be investigated in three parts. First, it is shown that the
Lorentz transformation formally stems from the First Relativity Postulate (FRP)
{\it alone} if space-time quantization is a fundamental law of physics which
must be included as part of the Postulate. An important corollary, however, is
that when measuring devices which carry the basic units of lengths and time
(e.g. a clock ticking every time quantum) are `moving' uniformly, they appear
to be measuring with larger units. Secondly, such an apparent increase in the
sizes of the quanta can be attributed to extra fluctuations associated with
motion, which are precisely described in terms of a thermally agitated harmonic
oscillator by using a temperature parameter. This provides a stringent
constraint on the microscopic properties of flat space-time: it is an array of
quantized oscillators. Thirdly, since the foregoing development would suggest
that the space-time array of an accelerated frame cannot be in thermal
equilibrium, (i.e. it will have a distribution of temperatures), the approach
is applied to the case of acceleration by the field of {\it any} point object,
which corresponds to a temperature `spike' in the array. It is shown that the
outward transport of energy by phonon conduction implies an inverse-square law
of force at low speeds, and the full Schwarzschild metric at high speeds. A
prediction of the new theory is that when two inertial observers move too fast
relative to each other, or when fields are too strong, anharmonic corrections
will modify effects like time dilation, and will lead to asymmetries which
implies that the FRP may not be sustainable in this extreme limit.

</DOC>
<DOC>
<DOCNO> 8122 </DOCNO>
Screening of a charged particle by multivalent counterions in salty


  Screening of a macroion such as a charged solid particle, a charged membrane,
double helix DNA or actin by multivalent counterions is considered. Small
colloidal particles, charged micelles, short or long polyelectrolytes can play
the role of multivalent counterions. Due to strong lateral repulsion at the
surface of macroion such multivalent counterions form a strongly correlated
liquid, with the short range order resembling that of a Wigner crystal. These
correlations create additional binding of multivalent counterions to the
macroion surface with binding energy larger than $k_BT$. As a result even for a
moderate concentration of multivalent counterions in the solution, their total
charge at the surface of macroion exceeds the bare macroion charge in absolute
value. Therefore, the net charge of the macroion inverts its sign. In the
presence of a high concentration of monovalent salt the absolute value of
inverted charge can be larger than the bare one. This giant inversion of charge
can be observed by electrophoresis or by direct counting of multivalent
counterions.

</DOC>
<DOC>
<DOCNO> 123076 </DOCNO>
Extragalactic Background Light, MACHOs, and the Cosmic Stellar Baryon


  The optical/far-IR extragalactic background light (EBL) from both resolved
and unresolved extragalactic sources is an indicator of the total luminosity of
cosmic structures, as the cumulative emission from young and evolved galactic
systems, as well as from active galactic nuclei (AGNs), is recorded in this
radiation. This is a brief review of some of the implications of the observed
brightness of the night sky for the stellar mass density and average
metallicity of the universe today, and of the possible contribution of MACHO
progenitors and QSOs to the EBL. Assuming a Salpeter initial mass function with
a cutoff below 0.6 M_sun, a lower limit of Omega_{g+s}h^2>0.0015 I_{60} can be
derived to the visible (recycled gas + stars) mass density required to generate
an EBL at a level of I_{EBL}=60 I_{60} nW/m^2/sr: our latest, best-guess
estimate is Omega_{g+s}h^2 ~ 0.0023 I_{60}, which implies a mean metallicity at
the present-epoch of y_Z Omega_{g+s}/Omega_b ~ 0.2 Z_sun. If massive dark halos
around spiral galaxies are partially composed of faint, old white dwarfs, i.e.
if a non-negligible fraction (a few percent) of the nucleosynthetic baryons is
locked in the remnants (MACHOs) of intermediate-mass stars forming at very high
redshifts, then the bright early phases of such halos should contribute
significantly to the observed EBL. Assuming a standard black hole accretion
model for quasar activity and using recent observations of the quasar
population and new synthesis models for the cosmic X-ray background, we
estimate a present mass density of QSO remnants of rho_{BH} ~ 3e5 M_sun/Mpc^3
for a 10% efficiency of accreted mass-to-radiation conversion. The quasar
contribution to the brightness of the night sky is I_QSO ~ 2 nW/m^2/sr.

</DOC>
<DOC>
<DOCNO> 174515 </DOCNO>
The $\pi\pi$ interaction in nuclear matter from a study of the $\pi^+ A


  The pion-production reactions $\pi^+ A \to \pi^+\pi^{\pm} A'$ were studied on
$^{2}H$, $^{12}C$, $^{40}Ca$, and $^{208}Pb$ nuclei at an incident pion energy
of $T_{\pi^{+}}$=283 MeV. Pions were detected in coincidence using the CHAOS
spectrometer. The experimental results are reduced to differential cross
sections and compared to both theoretical predictions and the reaction phase
space. The composite ratio $\cal C$$_{\pi\pi}^A$ between the $\pi^{+}\pi^{\pm}$
invariant masses on nuclei and on the nucleon is also presented. Near the
$2m_{\pi}$ threshold pion pairs couple to $(\pi\pi)_{I=J=0}$ when produced in
the $\pi^+\to \pi^+\pi^-$ reaction channel. There is a marked near-threshold
enhancement of $\cal C$$_{\pi^+\pi^-}^A$ which is consistent with theoretical
predictions addressing the partial restoration of chiral symmetry in nuclear
matter. Furthermore, the behaviour of $\cal C$$_{\pi^+\pi^-}^A$ is well
described when the restoration of chiral symmetry is combined with standard
P-wave renormalization of pions in nuclear matter. On the other hand, nuclear
matter only weakly influences $\cal C$$_{\pi^+\pi^+}^A$, which displays a flat
behaviour throughout the energy range regardless of $A$.

</DOC>
<DOC>
<DOCNO> 68726 </DOCNO>
Astrophysics and Cosmology


  These notes are intended as an introductory course for experimental particle
physicists interested in the recent developments in astrophysics and cosmology.
I will describe the standard Big Bang theory of the evolution of the universe,
with its successes and shortcomings, which will lead to inflationary cosmology
as the paradigm for the origin of the global structure of the universe as well
as the origin of the spectrum of density perturbations responsible for
structure in our local patch. I will present a review of the very rich
phenomenology that we have in cosmology today, as well as evidence for the
observational revolution that this field is going through, which will provide
us, in the next few years, with an accurate determination of the parameters of
our standard cosmological model.

</DOC>
<DOC>
<DOCNO> 116425 </DOCNO>
Phase changes in 38 atom Lennard-Jones clusters. I: A parallel tempering


  The heat capacity and isomer distributions of the 38 atom Lennard-Jones
cluster have been calculated in the canonical ensemble using parallel tempering
Monte Carlo methods. A distinct region of temperature is identified that
corresponds to equilibrium between the global minimum structure and the
icosahedral basin of structures. This region of temperatures occurs below the
melting peak of the heat capacity and is accompanied by a peak in the
derivative of the heat capacity with temperature. Parallel tempering is shown
to introduce correlations between results at different temperatures. A
discussion is given that compares parallel tempering with other related
approaches that ensure ergodic simulations.

</DOC>
<DOC>
<DOCNO> 72267 </DOCNO>
Decay rate asymmetry for $B \to X_s \gamma$ in SUSY model


  We discuss a rate asymmetry for the radiative $B$-meson decay $B \to X_s
\gamma$ within the framework of the supersymmetric standard model based on N=1
supergravity. This model contains new sources of CP violation. In spite of
severe experimental constraints on the electric dipole moment of the neutron, a
new CP-violating phase may not be suppressed, leading to a sizable enhancement
of the decay rate asymmetry. The magnitude of the asymmetry is predicted to be
larger than that by the standard model in wide parameter regions where the
branching ratio is consistent with its experimental bounds. A possible maximal
magnitude is about 0.1, which will be well accessible at B factories.

</DOC>
<DOC>
<DOCNO> 116453 </DOCNO>
Auditory Sensitivity Provided by Self-tuned Critical Oscillations of


  We introduce the concept of self-tuned criticality as a general mechanism for
signal detection in sensory systems. In the case of hearing, we argue that
active amplification of faint sounds is provided by a dynamical system which is
maintained at the threshold of an oscillatory instability. This concept can
account for the exquisite sensitivity of the auditory system and its wide
dynamic range, as well as its capacity to respond selectively to different
frequencies. A specific model of sound detection by the hair cells of the inner
ear is discussed. We show that a collection of motor proteins within a hair
bundle can generate oscillations at a frequency which depends on the elastic
properties of the bundle. Simple variation of bundle geometry gives rise to
hair cells with characteristic frequencies which span the range of audibility.
Tension-gated transduction channels, which primarily serve to detect the motion
of a hair bundle, also tune each cell by admitting ions which regulate the
motor protein activity. By controlling the bundle's propensity to oscillate,
this feedback automatically maintains the system in the operating regime where
it is most sensitive to sinusoidal stimuli. The model explains how hair cells
can detect sounds which carry less energy than the background noise.

</DOC>
<DOC>
<DOCNO> 120436 </DOCNO>
Synchrotron Radiation as the Source of Gamma-Ray Burst Spectra


  We investigate synchrotron emission models as the source of gamma-ray burst
spectra. We show that including the possibility for synchrotron
self-absorption, a ``smooth cutoff'' to the electron energy distribution, and
an anisotropic distribution for the electron pitch angles produces a whole
range of low energy spectral behavior. In addition, we show that the procedure
of spectral fitting to GRB data over a finite bandwidth can introduce a
spurious correlation between spectral parameters - in particular, the value of
the peak of the nu F_nu spectrum, E_p, and the low energy photon spectral index
alpha (the lower E_p is, the lower (softer) the fitted value of alpha will be).
  From this correlation and knowledge of the E_p distribution, we show how to
derive the expected distribution of alpha. We show that optically thin
synchrotron models with an isotropic electron pitch angle distribution can
explain the distribution of alpha below alpha=-2/3. This agreement is achieved
if we relax the unrealistic assumption of the presence of a sharp low energy
cutoff in the spectrum of accelerated electrons, and allow for a more gradual
break. We show that this low energy portion of the electron spectrum can be at
most flat. We also show that optically thin synchrotron models with an
anisotropic electron pitch angle distribution can explain all bursts with -2/3
< alpha <= 0$. The very few bursts with low energy spectral indices that fall
above alpha=0 may be due the presence of a the synchrotron self-absorption
frequency entering the lower end of the BATSE window. Our results also predict
a particular relationship between alpha and E_p during the temporal evolution
of a GRB. We give examples of spectral evolution in GRBs and discuss how the
behavior are consistent with the above models.

</DOC>
<DOC>
<DOCNO> 151954 </DOCNO>
Unified Field Theory Induced on the Brane World


  We show how the gravity, gauge, and matter fields are induced on dynamically
localized brane world.

</DOC>
<DOC>
<DOCNO> 84585 </DOCNO>
Loops and Knots as Topoi of Substance. Spinoza Revisited


  The relationship between modern philosophy and physics is discussed. It is
shown that the latter develops some need for a modernized metaphysics which
shows up as an ultima philosophia of considerable heuristic value, rather than
as the prima philosophia in the Aristotelian sense as it had been intended, in
the first place. It is shown then, that it is the philosophy of Spinoza in
fact, that can still serve as a paradigm for such an approach. In particular,
Spinoza's concept of infinite substance is compared with the philosophical
implications of the foundational aspects of modern physical theory. Various
connotations of sub-stance are discussed within pre-geometric theories,
especially with a view to the role of spin networks within quantum gravity. It
is found to be useful to intro-duce a separation into physics then, so as to
differ between foundational and empirical theories, respectively. This leads to
a straightforward connection bet-ween foundational theories and speculative
philosophy on the one hand, and between empirical theories and sceptical
philosophy on the other. This might help in the end, to clarify some recent
problems, such as the absence of time and causality at a fundamental level. It
is implied that recent results relating to topos theory might open the way
towards eventually deriving logic from physics, and also towards a possible
transition from logic to hermeneutic.

</DOC>
<DOC>
<DOCNO> 102787 </DOCNO>
Invitation to higher local fields, Part II, section 3: The Bruhat-Tits


  This work introduces author's theory of Bruhat-Tits buildings over higher
dimensional local fields. The theory is illustrated with the buildings for
PGL(2) and PGL(3) for one- and two-dimensional local fields.

</DOC>
<DOC>
<DOCNO> 85142 </DOCNO>
Spin foam model for Lorentzian General Relativity


  We present a spin foam formulation of Lorentzian quantum General Relativity.
The theory is based on a simple generalization of an Euclidean model defined in
terms of a field theory over a group. Its vertex amplitude turns out to be the
one recently introduced by Barrett and Crane. As in the case of its Euclidean
relatives, the model fully implements the desired sum over 2-complexes which
encodes the local degrees of freedom of the theory.

</DOC>
<DOC>
<DOCNO> 121304 </DOCNO>
The BeppoSAX observation of Mrk 766


  The Narrow Line Seyfert 1 galaxy Mrk 766 has been observed by BeppoSAX on May
1997. The source was fairly variable, both in flux and spectrum, during the
observation. The variability is the largest around 2 keV, possibly due to
variations in the warm absorber properties. An oxygen line is clearly detected,
at least in the first part of the observation. An edge around 7.5 keV, coupled
with the lack of any detectable iron line, suggests either reprocessing of the
primary X-rays by a mildly ionized disc or absorption by a further, thicker and
more ionized material.

</DOC>
<DOC>
<DOCNO> 72028 </DOCNO>
Chiral Quark Model with Configuration Mixing


  The implications of one gluon exchange generated configuration mixing in the
Chiral Quark Model ($\chi$QM$_{gcm}$) with SU(3) and axial U(1) symmetry
breakings are discussed in the context of proton flavor and spin structure as
well as the hyperon $\beta$-decay parameters. We find that $\chi$QM$_{gcm}$
with SU(3) symmetry breaking is able to give a satisfactory unified fit for
spin and quark distribution functions, with the symmetry breaking parameters
$\alpha=.4$, $\beta=.7$ and the mixing angle $\phi=20^o$, both for NMC and the
most recent E866 data. In particular, the agreement with data, in the case of
$G_A/G_V, \Delta_8$, F, D, $f_s$ and $f_3/f_8$, is quite striking.

</DOC>
<DOC>
<DOCNO> 68611 </DOCNO>
Supersymmetric Randall-Sundrum Scenario


  We present the supersymmetric version of the minimal Randall-Sundrum model
with two opposite tension branes.

</DOC>
<DOC>
<DOCNO> 68199 </DOCNO>
Effect of CP-violation on the sphaleron rate


  We calculate the effect of two CP-violating (dimension-eight) operators of
the SU(2)-Higgs model on the motion along a particular path from the vacuum to
the sphaleron. It turns out that CP-violation may introduce a difference
between the sphaleron rate towards larger Chern-Simons number and the rate
towards smaller Chern-Simons number. Such a difference induces a non-zero
baryon-number without a first order phase transition.

</DOC>
<DOC>
<DOCNO> 13706 </DOCNO>
Atomic Deuterium Adsorbed on the Surface of Liquid Helium


  We investigate deuterium atoms adsorbed on the surface of liquid helium in
equilibrium with a vapor of atoms of the same species. These atoms are studied
by a sensitive optical method based on spectroscopy at a wavelength of 122 nm,
exciting the 1S-2P transition. We present a direct measurement of the
adsorption energy of deuterium atoms on helium and show evidence for the
existence of resonantly enhanced recombination of atoms residing on the surface
to molecules.

</DOC>
<DOC>
<DOCNO> 71433 </DOCNO>
Long-range particle correlations and wavelets


  The problem of long-range correlations of particles produced in high- energy
collisions is discussed. Long-range correlations involve large groups of
particles. Among them are, e.g., those correlations which lead to ring-like and
elliptic flow shapes of individual high-multiplicity events in the
polar+azimuthal angles plane. The \w method of \an which allows to disentangle
various patterns has been proposed and applied to some central lead-lead
collisions at energy 158 GeV per nucleon. Previous attempts to find out the
ring-like correlations and recent results on \w \an of high- energy nuclei
interactions are reviewed.

</DOC>
<DOC>
<DOCNO> 11916 </DOCNO>
A Raman Study of Morphotropic Phase Boundary in PbZr1-xTixO3 at low


  Raman spectra of PbZr1-xTixO3 ceramics with titanium concentration varying
between 0.40 and 0.60 were measured at 7 K. By observing the
concentration-frequency dependence of vibrational modes, we identified the
boundaries among rhombohedral, monoclinic, and tetragonal ferroelectric phases.
The analysis of the spectra was made in the view of theory group analysis
making possible the assignment of some modes for the monoclinic phase.

</DOC>
<DOC>
<DOCNO> 70654 </DOCNO>
Low-Energy Predictions of Lopsided Family Charges


  We consider the Froggatt-Nielsen (FN) mechanism reproducing the observed mass
hierarchies and mixing angles for quarks and leptons. The large $\nu_\mu $-$
\nu_\tau$ mixing suggested from recent Superkamiokande experiments on the
atmospheric neutrinos implies lopsided FN U(1) charges for the lepton doublets.
There are two possible charge assignments to generate the large $\nu_\mu$-$
\nu_\tau$ mixing. We point out that the two models with different charge
assignments have distinct low-energy predictions and hence they are
distinguishable in future neutrino experiments on such as CP violation and
$2\beta 0\nu$ decay.

</DOC>
<DOC>
<DOCNO> 69222 </DOCNO>
On the Use of Transverse Momentum Spectra to probe Thermalisation and


  Transverse momentum spectra of the reaction products from proton-proton and
nucleus-nucleus collisions are discussed within the phenomenological frameworks
of statistical phase-space and string fragmentation models. It will be shown
that a string fragmentation model can accommodate all of the observations
discussed here and consequently it is claimed that no conclusion about the
thermal nature or collective expansion of the created system may be derived
from observed transverse momentum spectra.

</DOC>
<DOC>
<DOCNO> 67735 </DOCNO>
Motion of a scalar field coupled to a Yang Mills field reformulated


  This paper exposes a reformulation of some gauge theories in terms of
explicitly gauge-invariant variables. We show in the case of Scalar QED that
the classical theory can be reformulated locally with some gauge invariant
variables. We discuss the form of some realistic asymptotic solutions to these
equations. The equations of motion are then also reformulated in the
non-abelian case.

</DOC>
<DOC>
<DOCNO> 178870 </DOCNO>
Electromagnetic isoscalar rho-pi-gamma exchange current and the


  Using modern data, we first refit constants needed to complete an anomalous
pi-rho-omega-a_1 Lagrangian obtained within the approach of hidden local
symmetries. Then we derive from this Lagrangian electromagnetic isoscalar
rho-pi-gamma and rho-a_1-gamma currents needed in calculations of the deuteron
electromagnetic form factors at large momentum transfers.

</DOC>
<DOC>
<DOCNO> 69911 </DOCNO>
Gravity with a dynamical preferred frame


  We study a generally covariant model in which local Lorentz invariance is
broken "spontaneously" by a dynamical unit timelike vector field $u^a$---the
"aether". Such a model makes it possible to study the gravitational and
cosmological consequences of preferred frame effects, such as ``variable speed
of light" or high frequency dispersion, while preserving a generally covariant
metric theory of gravity. In this paper we restrict attention to an action for
an effective theory of the aether which involves only the antisymmetrized
derivative $\nabla_{[a}u_{b]}$. Without matter this theory is equivalent to a
sector of the Einstein-Maxwell-charged dust system. The aether has two massless
transverse excitations, and the solutions of the model include all vacuum
solutions of general relativity (as well as other solutions). However, the
aether generally develops gradient singularities which signal a breakdown of
this effective theory. Including the symmetrized derivative in the action for
the aether field may cure this problem.

</DOC>
<DOC>
<DOCNO> 120641 </DOCNO>
Pulsar Jets: Implications for Neutron Star Kicks and Initial Spins


  We study implications for the apparent alignment of the spin axes,
proper-motions, and polarization vectors of the Crab and Vela pulsars. The spin
axes are deduced from recent Chandra X-ray Observatory images that reveal jets
and nebular structure having definite symmetry axes. The alignments indicate
these pulsars were born either in isolation or with negligible velocity
contributions from binary motions. We examine the effects of rotation and the
conditions under which spin-kick alignment is produced for various models of
neutron star kicks. If the kick is generated when the neutron star first forms
by asymmetric mass ejection or/and neutrino emission, then the alignment
requires that the protoneutron star possesses an original spin with period
$P_s$ much less than the kick timescale, thus spin-averaging the kick forces.
The kick timescale ranges from 100 ms to 10 s depending on whether the kick is
hydrodynamically driven or neutrino-magnetic field driven. For hydrodynamical
models, spin-kick alignment further requires the rotation period of an
asymmetry pattern at the radius near shock breakout (>100 km) to be much less
than ~100 ms; this is difficult to satisfy unless rotation plays a dynamically
important role in the core collapse and explosion ($P_s\lo 1$ ms). Aligned kick
and spin vectors are inherent to the slow process of asymmetric electromagnetic
radiation from an off-centered magnetic dipole. We reassess the viability of
this effect, correcting a factor of 4 error in Harrison and Tademaru's
calculation that increases the size of the effect. To produce a kick velocity
of order a few hundred km/s requires that the neutron star be born with an
initial spin close to 1 ms and that spindown due to r-mode driven gravitational
radiation be inefficient compared to standard magnetic braking.

</DOC>
<DOC>
<DOCNO> 121172 </DOCNO>
The Composite Broad Band Spectrum of Cir X-1 at the Periastron: a


  We report on the spectral analysis of the peculiar source Cir X-1 observed by
the BeppoSAX satellite when the X-ray source was near the periastron. A flare
lasting $\sim 6 \times 10^3$ s is present at the beginning of the observation.
The luminosity during the persistent emission is $1 \times 10^{38}$ erg
s$^{-1}$, while during the flare is $2 \times 10^{38}$ erg s$^{-1}$. We
produced broad band (0.1-100 keV) energy spectra during the flare and the
persistent emission. At low energies the continuum is well fitted by a model
consisting of Comptonization of soft photons, with a temperature of $\sim 0.4$
keV, by electrons at a temperature of $\sim 1$ keV. Out of the flare a
power-law component, with photon index $\sim 3$, is dominant at energies higher
than 10 keV. This component contributes to $\sim 4%$ of the total luminosity.
During the flare its addition is not statistically significant. An absorption
edge at $\sim 8.4$ keV, with optical depth $\sim 1$, corresponding to the
K-edge of Fe XXIII-XXV, and an iron emission line at 6.7 keV are also present.
The iron line energy is in agreement with the ionization level of the
absorption edge. The hydrogen column deduced from the absorption edge is $\sim
10^{24}$ cm$^{-2}$, two order of magnitude larger than the absorption measured
in this source. We calculated the radius of the region originating the
comptonized seed photons, $R_W \sim 150$ km.
  We propose a scenario where $R_W$ is the inner disk radius, a highly ionized
torus surrounds the accretion disk and a magnetosphere is large up to $R_W$.
The absorption edge and the emission line could originate in the photoionized
torus, while the comptonized component originates in an inner region of the
disk.

</DOC>
<DOC>
<DOCNO> 118916 </DOCNO>
A Systematic Search for Short-term Variability of EGRET Sources


  The 3rd EGRET Catalog of High-energy Gamma-ray Sources contains 170
unidentified sources, and there is great interest in the nature of these
sources. One means of determining source class is the study of flux variability
on time scales of days; pulsars are believed to be stable on these time scales
while blazars are known to be highly variable. In addition, previous work has
demonstrated that 3EG J0241-6103 and 3EG J1837-0606 are candidates for a new
gamma-ray source class. These sources near the Galactic plane display transient
behavior but cannot be associated with any known blazars. Although many
instances of flaring AGN have been reported, the EGRET database has not been
systematically searched for occurrences of short-timescale ($\sim1$ day)
variability. These considerations have led us to conduct a systematic search
for short-term variability in EGRET data, covering all viewing periods through
proposal cycle 4. Six 3EG catalog sources are reported here to display
variability on short time scales; four of them are unidentified. In addition,
three non-catalog variable sources are discussed.

</DOC>
<DOC>
<DOCNO> 83408 </DOCNO>
The Light Lexicographic path Ordering


  We introduce syntactic restrictions of the lexicographic path ordering to
obtain the Light Lexicographic Path Ordering. We show that the light
lexicographic path ordering leads to a characterisation of the functions
computable in space bounded by a polynomial in the size of the inputs.

</DOC>
<DOC>
<DOCNO> 71687 </DOCNO>
Flow at the SPS and RHIC as a Quark Gluon Plasma Signature


  Radial and elliptic flow in non-central heavy ion collisions can constrain
the effective Equation of State(EoS) of the excited nuclear matter. To this
end, a model combining relativistic hydrodynamics and a hadronic transport
code(RQMD [17]) is developed. For an EoS with a first order phase transition,
the model reproduces both the radial and elliptic flow data at the SPS. With
the EoS fixed from SPS data, we quantify predictions at RHIC where the Quark
Gluon Plasma(QGP) pressure is expected to drive additional radial and elliptic
flow. Currently, the strong elliptic flow observed in the first RHIC
measurements does not conclusively signal this nascent QGP pressure. Additional
measurements are suggested to pin down the EoS.

</DOC>
<DOC>
<DOCNO> 10587 </DOCNO>
Fractional power-law conductivity in SrRuO_3 and its consequences


  We combine the results of terahertz time-domain spectroscopy with
far-infrared transmission and reflectivity to obtain the conductivity of
SrRuO_3 over an unprecedented continuous range in frequency, allowing us to
characterize the approach to zero frequency as a function of temperature. We
show that the conductivity follows a simple phenomenological form, with an
analytic structure fundamentally different from that predicted by the standard
theory of metals.

</DOC>
<DOC>
<DOCNO> 9691 </DOCNO>
Nonequilibrium Campbell length: probing the vortex pinning potential


  The $AC$ magnetic penetration depth $\lambda (T,H,j)$ was measured in
presence of a macroscopic $DC$ (Bean) supercurrent, $j$. In single crystal
BSCCO below approximately 28 K, $\lambda (T,H,j)$ exhibits thermal hysteresis.
The irreversibility arises from a shift of the vortex position within its
pinning well as $j$ changes. It is demonstrated that below a new
irreversibility temperature, the nonequilibrium Campbell length depends upon
the ratio $j/j_c$. $\lambda (T,H,j)$ {\it increases} with $j/j_c$ as expected
for a non-parabolic potential well whose curvature {\it decreases} with the
displacement. Qualitatively similar results are observed in other high-$T_{c}$
and conventional superconductors.

</DOC>
<DOC>
<DOCNO> 152031 </DOCNO>
Topologically massive nonabelian BF models in arbitrary space-time


  This work extends to the D-dimensional space-time the topological mass
generation mechanism of the nonabelian BF model in four dimensions. In order to
construct the gauge invariant nonabelian kinetic terms for a (D-2)-form B and a
1-form A, we introduce an auxiliary (D-3)-form V. Furthermore, we obtain a
complete set of BRST and anti-BRST transformation rules of the fields using the
so called horizontality condition, and construct a BRST/anti-BRST invariant
quantum action for the model in D-dimensional space-time.

</DOC>
<DOC>
<DOCNO> 118243 </DOCNO>
A spatially resolved plerionic X-ray nebula around PSR B0540-69


  We present a high resolution Chandra X-ray observation of PSR B0540-69, the
Crab-like 50 msec pulsar in the Large Magellanic Cloud. We use phase-resolved
imaging to decompose the extended X-ray emission, as expected of a synchrotron
nebula, from the point-like emission of the pulsar. The image of the pulsed
X-ray emission shows a well-defined point-spread function of the observation,
while the resolved nebula has a morphology and size remarkably similar to the
Crab nebula, including evidence for a jet-like feature from PSR B0540-69. The
patchy outer shell, which most likely represents the expanding blast-wave of
the supernova, is reminiscent of that seen in radio. Based on morphology, size,
and energetics there can be little doubt that PSR B0540-69 is an analogous
system to the Crab but located in our neighboring galaxy.

</DOC>
<DOC>
<DOCNO> 170296 </DOCNO>
Experimental realization of optimal detection strategies for


  We present the results of generalized measurements of optical polarization
designed to provide one of three or four distinct outcomes. This has allowed us
to discriminate between nonorthogonal polarization states with an error
probability that is close to the minimum allowed by quantum theory. Employing
these optimal detection strategies on sets of three (trine) or four (tetrad)
equiprobable symmetric nonorthogonal polarization states, we obtain a mutual
information that exceeds the maximum value attainable using conventional (von
Neumann) polarization measurements.

</DOC>
<DOC>
<DOCNO> 12369 </DOCNO>
Phase Diagram and Thermodynamic Properties of the Square Lattice of


  The magnetic phase diagram and the thermodynamic properties of a square
lattice containing antiferromagnetically coupled spin-1/2 triangles are
studied. A Heisenberg Hamiltonian with three strong intra-triangle exchange
coupling constants and one weak inter-triangle exchange coupling constant is
proposed to model the interacting Cu^2+ ions of the Cu_3MoO_4 planes in
La_4Cu_3MoO_12. Depending on the ratio of the intra-triangle coupling
constants, various long-ranged magnetic phases are shown to compete at low
temperatures. A comparison of numerical calculations of thermodynamic
properties in the model Hamiltonian with recent experiments on La_4Cu_3MoO_12
suggests that the spins in this material order antiferromagnetically along the
x-direction and ferromagnetically along the y-direction of the Cu_3MoO_4
planes. The temperature dependence of the uniform magnetic susceptibility, the
heat capacity, and the entropy are calculated and are shown to be in
qualitative agreement with the experiments on this compound.

</DOC>
<DOC>
<DOCNO> 68092 </DOCNO>
One-loop sfermion corrections to $e^-e^+ \to W^-W^+$ in the MSSM


  We study one-loop effects of sfermions on helicity amplitudes for $\eeww$ in
the Minimal Supersymmetric Standard Model. The one-loop contributions are
calculated in the $\bar{\rm MS}$ renormalization scheme. In order to verify the
validity of the analytic calculation and the numerical program, the following
tests are performed. (i) The BRS sum rules hold exactly among the analytic
expressions of the form factors of the $\eeww$ amplitude and those of the
amplitudes where the external $W^\pm$ bosons are replaced by the corresponding
Goldstone bosons $\chi^\pm$, hence they hold within the expected accuracy of
the numerical program. (ii) The one-loop sfermion contribution to the
amplitudes decouple in the heavy mass limit. This property is used to test the
overall normalization of the amplitudes. In order to observe the analytically
exact decoupling, the amplitudes are expanded by the $\bar{\rm MS}$ couplings
of the Standard Model. (iii) The high-energy analytic formulas of the helicity
amplitudes, which are verified by using the equivalence theorem analytically,
are used for the numerical test of the high energy behavior of the amplitudes.
We then investigate the magnitude of the one-loop effects on each helicity
amplitude which may be measured by experiments at future linear colliders.
Under the constraint from available precision data, the one-loop corrections to
a few helicity amplitudes (for example, the longitudinal-$W$-pair production)
can be at most from -0.8% to $+0.6$% in magnitude in the observables. The
corrections in the helicity-summed cross sections are smaller, typically a few
times $\pm 0.1$% at large scattering angles.

</DOC>
<DOC>
<DOCNO> 68615 </DOCNO>
Issues in Leading Particle and Charm Production in DIS at HERA


  A Monte Carlo simulation based on O(alpha_s) QCD matrix elements matched to
parton showers shows that final-state hadrons in deep inelastic scattering
(DIS) can be used to tag events with a single (anti)quark recoiled against the
proton. The method is particularly suited to study the mean charge of leading
particles, which is sensitive to fragmentation and sea quark contribution to
the proton structure function. We also discuss methods to study the charm
production in DIS using the Breit frame.

</DOC>
<DOC>
<DOCNO> 121957 </DOCNO>
HST Color-Magnitude Data for Globular Clusters: I. Transformations


  We present deep Hubble Space Telescope optical imaging observations of two
Galactic globular clusters, 47 Tuc and M15, using the Space Telescope Imaging
Spectrograph (STIS) longpass (LP) filter and the Wide Field and Planetary
Camera 2 (WFPC2) F606W and F814W filters. These globular clusters have very
different metallicities ([Fe/H] = -0.7 dex for 47 Tuc, and [Fe/H] = -2.2 dex
for M15), essentially spanning the metallicity distribution of the entire Milky
Way globular cluster system, and were chosen to investigate the relationship
between magnitudes in the non-standard STIS LP system and the better
characterized WFPC2 magnitudes. We determine this relationship by combining our
new STIS data with archival WFPC2 data, taking care to provide a robust and
reliable transformation. Examining the 47 Tuc and M15 data separately, there is
no evidence for a metallicity dependence in the transformation relations. This
allows us to combine the data for both clusters, and also include the stars in
the Small Magellanic Cloud that lie within the field of view of the 47 Tuc
images, to determine final transformations that are valid for main sequence
stars with colors in the range 0.3 < V606-I814 < 1.8. These final relations
predict STIS magnitudes within 0.05 mag (1 sigma) of those measured for stars
in both clusters. In an appendix, we discuss the differences between our
empirical transformation relations and those predicted by synthetic photometry.

</DOC>
<DOC>
<DOCNO> 69379 </DOCNO>
On Brane-World Cosmology


  In the study of three-brane cosmological models, an unusual law of
cosmological expansion on the brane has been reported. According to this law,
the energy density of matter on the brane quadratically enters the right-hand
side of the new equations for the brane world, in contrast with the standard
cosmology, where it enters the similar equations linearly. However, this result
is obtained in the absence of curvature-dependent terms in the action for the
brane. In this paper, we derive the field equations for a brane world embedded
into a five-dimensional spacetime in the case where such terms are present. We
also discuss some cosmological solutions of the resulting equations.

</DOC>
<DOC>
<DOCNO> 80905 </DOCNO>
Unquenched Charmonium with NRQCD - Lattice 2000


  We present results from a series of NRQCD simulations of the charmonium
system, both in the quenched approximation and with n_f = 2 dynamical quarks.
The spectra show evidence for quenching effects of ~10% in the S- and
P-hyperfine splittings. We compare this with other systematic effects.
Improving the NRQCD evolution equation altered the S-hyperfine by as much as 20
MeV, and we estimate radiative corrections may be as large as 40%.

</DOC>
<DOC>
<DOCNO> 151793 </DOCNO>
Universality or Non--Universality of Absorption Cross Sections for


  The calculation of absorption cross sections for minimal scalars in
supergravity backgrounds is an important aspect of the investigation of AdS/CFT
correspondence and requires a matching of appropriate wave functions. The low
energy case has attracted particular attention. In the following the dependence
of the cross section on the matching point is investigated. It is shown that
the low energy limit is independent of the matching point and hence exhibits
universality. In the high energy limit the independence is not maintained, but
the result is believed to possess the correct energy dependence.

</DOC>
<DOC>
<DOCNO> 178909 </DOCNO>
Phase Transitions in Dense Matter and Recent Topics of Neutron Stars


  Core of neutron star consists of highly dense matter above normal nuclear
density, where phase transitions is expected to take place. We review some
phase transitions and recent topics of neutron stars.

</DOC>
<DOC>
<DOCNO> 68046 </DOCNO>
Non perturbative renormalization group potentials and quintessence


  New solutions to the non perturbative renormalization group equation for the
effective action of a scalar field theory in the Local Potential Approximation
having the exponential form $e^{\pm\phi}$ are found. This result could be
relevant for those quintessence phenomenological models where this kind of
potentials are already used, giving them a solid field theoretical derivation.
Other non perturbative solutions, that could also be considered for the
quintessence scenario, are also found. Apart from this particular cosmological
application, these results could be relevant for other models where scalar
fields are involved, in particular for the scalar sector of the standard model.

</DOC>
<DOC>
<DOCNO> 12453 </DOCNO>
Coqblin-Schrieffer impurity in a singular metal


  A Coqblin-Schrieffer impurity of spin $S$ coupled to the boundary of an open
SU(N)-invariant $t-J$ chain with $N = 2S+2$ is studied. The model is integrable
as a function of one coupling parameter $v$ for arbitrary spin and band
filling. The system is coupled to a reservoir of electrons and as a function of
the chemical potential the host chain has a critical point corresponding to the
van Hove singularity of the empty band of charges. In the neighborhood of this
critical point we study the low temperature properties of the impurity as a
function of $v$. For constant chemical potential we obtain two critical
coupling values $v_1=-1/2$ and $v_2=0$ separating phases in which the impurity
spin is completely compensated (Kondo effect), partially screened
(undercompensated impurity) or decoupled from the chain (free spin). The
partial compensation occurs as a consequence of a thermally {\it activated
Kondo effect} in the region $v_1 < v < v_2$. The possible realization of such a
{\it finite temperature Kondo effect} in narrow-gap semiconductors is
discussed.

</DOC>
<DOC>
<DOCNO> 11351 </DOCNO>
Structural and magnetic aspects of the metal insulator transition in


  The phase diagram of Ca$_{2-x}$Sr$_x$RuO$_4$ has been studied by neutron
diffraction on powder and single-crystalline samples. The experiments reveal
antiferromagnetic order and structural distortions characterized by tilts and
rotations of the RuO$_6$-octahedra. There is strong evidence that the
structural details of the isovalent samples tune the magnetic as well as the
electronic behavior. In particular we observe for low Sr-concentration a metal
insulator transition associated with a structural change and magnetic ordering.

</DOC>
<DOC>
<DOCNO> 80726 </DOCNO>
Topological Obstruction in Block-spin Transformations


  Block-spin transformations from a fine lattice to a coarse one are shown to
give rise to a one-to-one correspondence between the zero-modes of the
Ginsparg-Wilson Dirac operators. The index is then preserved under the blocking
process. Such a one-to-one correspondence is violated and the block-spin
transformation becomes necessarily ill-defined when the absolute value of the
index is larger than 2rN, where N is the number of the sites on the coarse
lattice and r is the dimension of the gauge group representation of the fermion
variables.

</DOC>
<DOC>
<DOCNO> 101720 </DOCNO>
Projective bundles of singular plane cubics


  Classification theory and the study of projective varieties which are covered
by rational curves of minimal degrees naturally leads to the study of families
of singular rational curves. Since families of arbitrarily singular curves are
hard to handle, it has been shown in a previous paper that there exists a
partial resolution of singularities which transforms a bundle of possibly badly
singular curves into a bundle of nodal and cuspidal plane cubics.
  In cases which are of interest for classification theory, the total spaces of
these bundles will clearly be projective. It is, however, generally false that
an arbitrary bundle of plane cubics is globally projective. For that reason the
question of projectivity seems to be of interest, and the present work gives a
characterization of the projective bundles.

</DOC>
<DOC>
<DOCNO> 11097 </DOCNO>
Commensurate-incommensurate transition in two-coupled chains of nearly


  We investigate the physical properties of two coupled chains of electrons,
with a nearly half-filled band, as a function of the interchain hopping t_\perp
and the doping. We show that upon doping, the system undergoes a
metal-insulator transition well described by a commensurate-incommensurate
transition. By using bosonization and renormalization we determine the full
phase diagram of the system, and the physical quantities such as the charge
gap. In the commensurate phase two different regions, for which the interchain
hopping is relevant and irrelevant exist, leading to a
confinement-deconfinement crossover in this phase. A minimum of the charge gap
is observed for values of t_\perp close to this crossover. At large t_\perp the
region of the commensurate phase is enhanced, compared to a single chain. At
the metal-insulator transition the Luttinger parameter takes the universal
value K_\rho^*=1, in agreement with previous results on special limits of this
model.

</DOC>
<DOC>
<DOCNO> 119589 </DOCNO>
Testing the photoionization models of powerful radio galaxies: Mixed


  The photoionization models for the narrow emission line regions of powerful
radio galaxies have yet to be tested in depth. To this end, we present
high-quality long-slit spectroscopy of the powerful double-nucleus radio galaxy
3C 321. The data have good enough spatial resolution to be able to trace the
variation in emission-line properties on kpc scales. Continuum modelling and
subtraction enables the faint emission line fluxes to be measured in several
regions across the emission line nebula. We plot diagnostic line-ratio diagrams
and compare them with the predictions of various photoionization models,
finding that the data is best fit by models which assume a mixture of optically
thin and thick clouds illuminated by a power-law continuum.
  The emission line kinematics, line ratios and deduced physical conditions
show remarkably little variation across the source. We deduce a mean electron
density of 400 +/- 120 cm-3 and a mean temperature of 11500 +/- 1500 K.
Assuming a single population of optically thick line-emitting clouds, we
calculate a mean photoionization parameter of (1.1 +/- 0.5) x 10e-2 and hence a
photoionizing photon luminosity of Q ~ 10e55 -- 10e56 photon/s/sr. This
indicates a central engine as luminous as that of the powerful quasar 3C 273,
yet there is no evidence for such an energetically prolific central engine at
either far-infrared or radio wavelengths. We therefore conclude that the
mixed-media models, which give Q ~ 5 x 10e53 -- 5 x 10e54, represent a more
likely scenario.
  As a by-product of the continuum subtraction we infer that young stellar
populations account for ~ 0.4% of the visible stellar mass in the galaxy, and
that these populations are spatially extended.

</DOC>
<DOC>
<DOCNO> 101285 </DOCNO>
Rectangle diagrams for the Lusztig cones of quantized enveloping


  Let U be the quantum group associated to a Lie algebra of type A_n. The
negative part U^- of U has a canonical basis B defined by Lusztig and
Kashiwara, with favourable properties. We show how the spanning vectors of the
cones defined by Lusztig when regarded as monomials in Kashiwara's root
operators, can be described using a remarkable rectangle combinatorics. We use
this to calculate the Lusztig parameters of the corresponding canonical basis
elements, conjecturing that translates of these vectors span the simplicial
regions of linearity of Lusztig's piecewise-linear function.
  Keywords: quantum group, canonical basis, Lusztig cone, longest word,
piecewise-linear combinatorics.

</DOC>
<DOC>
<DOCNO> 122591 </DOCNO>
Sub-mm clues to elliptical galaxy formation


  There is growing evidence that, at the S(850) < 1 mJy level, the sub-mm
galaxy population (and hence a potentially significant fraction of the sub-mm
background) is associated with the star-forming Lyman-break population already
detected at optical wavelengths. However, the implied star-formation rates in
such objects (typically 3-30 solar masses per year) fall one or two orders of
magnitude short of the level of star-forming activity required to produce the
most massive elliptical galaxies on a timescale ~ 1 Gyr. If a significant
fraction of massive ellipticals did form the bulk of their stars in short-lived
massive starbursts at high redshift, then they should presumably be found among
the brighter, S(850) ~ 10 mJy sub-mm sources which are undoubtedly not part of
the Lyman-break population. A first powerful clue that this is indeed the case
comes from our major SCUBA survey of radio galaxies, which indicates that
massive dust-enshrouded star-formation in at least this subset of massive
ellipticals is largely confined to z > 2.5, with a mean redshift z = 3.5. While
radio selection raises concerns about bias, I argue that our current knowledge
of the brightest (S(850) ~ 10 mJy) sub-mm sources detected in unbiased SCUBA
imaging surveys indicates that they are also largely confined to this same
high-z regime. Consequently, while the most recent number counts imply such
extreme sources can contribute only 5-10% of the sub-mm background, their
comoving number density (in the redshift band 3 < z < 5) is 1-2 x 10^{-5} per
cubic megaparsec, sufficient to account for the formation of all ellipticals of
comparable mass to radio galaxies (~4L-star) in the present-day universe.

</DOC>
<DOC>
<DOCNO> 151206 </DOCNO>
Matrix Theory Compactification on Noncommutative $T^4/Z_2$


  In this paper, we construct gauge bundles on a noncommutative toroidal
orbifold $T^4_\theta/Z_2$. First, we explicitly construct a bundle with
constant curvature connections on a noncommutative $T^4_\theta$ following
Rieffel's method. Then, applying the appropriate quotient conditions for its
$Z_2$ orbifold, we find a Connes-Douglas-Schwarz type solution of matrix theory
compactified on $T^4_\theta/Z_2$. When we consider two copies of a bundle on
$T^4_\theta$ invariant under the $Z_2$ action, the resulting Higgs branch
moduli space of equivariant constant curvature connections becomes an ordinary
toroidal orbifold $T^4/Z_2$.

</DOC>
<DOC>
<DOCNO> 170291 </DOCNO>
Generalized quantum XOR-gate for quantum teleportation and state


  A generalization of the quantum XOR-gate is presented which operates in
arbitrary dimensional Hilbert spaces. Together with one-particle Fourier
transforms this gate is capable of performing a variety of tasks which are
important for quantum information processing in arbitrary dimensional Hilbert
spaces. Among these tasks are the preparation of Bell states, quantum
teleportation and quantum state purification. A physical realization of this
generalized XOR-gate is proposed which is based on non-linear optical elements.

</DOC>
<DOC>
<DOCNO> 101768 </DOCNO>
Blocks of Lie Superalgebras of Type W(n)


  We calculate the blocks of the category of finite-dimensional representations
of W(0,n), with n > 2, and show that all are of wild type. As an application,
we show that the centre of the universal enveloping algebra is trivial.

</DOC>
<DOC>
<DOCNO> 118769 </DOCNO>
The Evolution of Galaxies on Cosmological Timescales


  I discuss the chemical and spectrophotometric evolution of galaxies over
cosmological timescales and present a first attempt to treat both aspects in a
chemically consistent way. In our evolutionary synthesis approach, we account
for the increasing metallicity of successive generations of stars and use sets
of stellar evolutionary tracks, stellar yields, spectra, etc. for various
metallicities. This gives a more realistic description of nearby galaxies,
which are observed to have broad stellar metalllicty distributions, as well as
of young galaxies at high redshift. Selected results are presented for the
chemo-cosmological evolution of galaxies as compared to QSO absorption line
observations and for the spectrophotometric evolution of galaxies to very high
redshifts. On cosmological timescales, intercations are important drivers of
galaxy evolution. Neglecting dynamical aspects we study the effects of
interaction-induced starbursts on the spectrophotometric and chemical evolution
of galaxies and briefly discuss the formation of star clusters and Tidal Dwarf
Galaxies in this context.

</DOC>
<DOC>
<DOCNO> 170583 </DOCNO>
Dirac's hole theory versus quantum field theory


  Dirac's hole theory and quantum field theory are usually considered
equivalent to each other. For models of a certain type, however, the
equivalence may not hold as we discuss in this Letter. This problem is closely
related to the validity of the Pauli principle in intermediate states of
perturbation theory.

</DOC>
<DOC>
<DOCNO> 68617 </DOCNO>
Semi-Exclusive Production of Photons at HERA


  We study the feasibility of measuring semi-exclusive photon production \gamma
+ p \to \gamma + Y at HERA. The cross section of photons produced at large
transverse momenta, recoiling off an inclusive system Y of limited mass, can
without photon isolation cuts be simply expressed in terms of hard pQCD
subprocesses and standard target parton distributions. With the help of event
generators we identify the kinematic region where quark and gluon fragmentation
processes can be neglected. The cross section in this semi-exclusive region is
large enough to be measured with an upgraded HERA luminosity of L = 100/pb. The
subprocesses of lowest order in \alpha_s are suppressed at low recoil masses
M_Y, compared to higher order gluon exchange, i.e. BFKL contributions. The
distinct M_Y-dependence makes it possible to determine experimentally the
kinematic range where the higher order processes dominate.

</DOC>
<DOC>
<DOCNO> 119212 </DOCNO>
Vertical structure of the accreting two-temperature corona and the


  We investigate the model of the disc/corona accretion flow around the black
hole. The model, parameterized by the total (i.e. disk plus corona) accretion
rate, $\dot m$, mass of the black hole, $M$ and the viscosity parameter,
$\alpha$, uniquely determines the fraction of energy released in the corona as
a function of radius and, in particular, the transition radius to the
single-phase ADAF flow. Self-consistent solutions with the mass exchange
between phases display radial dependence of the parameters. This model
reproduces all characteristic luminosity states of accretion black hole without
any additional ad hoc assumptions. In particular. the mechanism of the disk
evaporation leads to a new, almost horizontal branch on the accretion flow's
stability curve (i.e. the dependence of accretion rate on surface density) at
the critical accretion rate.

</DOC>
<DOC>
<DOCNO> 12948 </DOCNO>
Theory of Ferromagnetism in Diluted Magnetic Semiconductors


  Carrier-induced ferromagnetism has been observed in several (III,Mn)V
semiconductors. We review the theoretical picture of these ferromagnetic
semiconductors that emerges from a model with kinetic-exchange coupling between
localized Mn spins and valence-band carriers. We discuss the applicability of
this model, the validity of a mean-field approximation for its interaction term
widely used in the literature, and validity limits for the simpler RKKY model
in which only Mn spins appear explicitly. Our conclusions are based in part on
our analysis of the dependence of the system's elementary spin excitations on
carrier density and exchange-coupling strength. The analogy between this system
and spin-model ferrimagnets is explored. Finally, we list several extensions of
this model that can be important in realistic modeling of specific materials.

</DOC>
<DOC>
<DOCNO> 116633 </DOCNO>
Excitations of oscillations in loaded systems with internal degrees of


  We show that oscillations are excited in a complex system under the influence
of the external force, if the parameters of the system experience rapid change
due to the changes in its internal structure. This excitation is collision-like
and does not require any phase coherence or periodicity. The change of the
internal structure may be achieved by other means which may require much lower
energy expenses. The mechanism suggests control over switching oscillations on
and off and may be of practical use.

</DOC>
<DOC>
<DOCNO> 40418 </DOCNO>
Recent Results from SELEX


  The SELEX experiment (E781) is 3-stage magnetic spectrometer for the study of
charm hadroproduction at large xF using 600 Gev Sigma-, pi- and p beams. New
precise measurements of the Lambda_c, D0, and Ds lifetimes are presented. We
also report results on Lambda_c and Ds production by Sigma-, pi- and p beams at
xF>0.2. The data agree with expectations from color-drag models to explain
charm particle/antiparticle production asymmetries.

</DOC>
<DOC>
<DOCNO> 13545 </DOCNO>
Accurate calculation of polarization-related quantities in


  We demonstrate that polarization-related quantities in semiconductors can be
predicted accurately from first-principles calculations using the appropriate
approach to the problem, the Berry-phase polarization theory. For III-V
nitrides, our test case, we find polarizations, polarization differences
between nitride pairs, and piezoelectric constants quite close to their
previously established values. Refined data are nevertheless provided for all
the relevant quantities.

</DOC>
<DOC>
<DOCNO> 170052 </DOCNO>
Multiphoton Resonant Transitions of Electrons in the Laser Field in a


  Within the scope of the relativistic quantum theory for electron-laser
interaction in a medium and using the resonant approximation for the two
degenerated states of an electron in a monochromatic radiation field [1] a
nonperturbative solution of the Dirac equation (nonlinear over field solution
of the Hill type equation) are obtained. The multiphoton cross sections of
electrons coherent scattering on the plane monochromatic wave at the Cherenkov
resonance are obtained taking into account the specificity of induced Cherenkov
process [1, 2] and spin-laser interaction as well. In the result of this
resonant scattering the electron beam quantum modulation at high frequencies
occurs that corresponds to a quantity of an electron energy exchange at the
coherent reflection from the ''phase lattice'' of slowed plane wave in a
medium. So, we can expect to have a coherent X-ray source in induced Cherenkov
process, since such beam is a potential source of coherent radiation itself.

</DOC>
<DOC>
<DOCNO> 13220 </DOCNO>
Branching and annihilating Levy flights


  We consider a system of particles undergoing the branching and annihilating
reactions A -> (m+1)A and A + A -> 0, with m even. The particles move via
long-range Levy flights, where the probability of moving a distance r decays as
r^{-d-sigma}. We analyze this system of branching and annihilating Levy flights
(BALF) using field theoretic renormalization group techniques close to the
upper critical dimension d_c=sigma, with sigma<2. These results are then
compared with Monte-Carlo simulations in d=1. For sigma close to unity in d=1,
the critical point for the transition from an absorbing to an active phase
occurs at zero branching. However, for sigma bigger than about 3/2 in d=1, the
critical branching rate moves smoothly away from zero with increasing sigma,
and the transition lies in a different universality class, inaccessible to
controlled perturbative expansions. We measure the exponents in both
universality classes and examine their behavior as a function of sigma.

</DOC>
<DOC>
<DOCNO> 85228 </DOCNO>
Hawking radiation in different coordinate settings: Complex paths


  We apply the technique of complex paths to obtain Hawking radiation in
different coordinate representations of the Schwarzschild space-time. The
coordinate representations we consider do not possess a singularity at the
horizon unlike the standard Schwarzschild coordinate. However, the event
horizon manifests itself as a singularity in the expression for the
semiclassical action. This singularity is regularized by using the method of
complex paths and we find that Hawking radiation is recovered in these
coordinates indicating the covariance of Hawking radiation as far as these
coordinates are concerned.

</DOC>
<DOC>
<DOCNO> 119815 </DOCNO>
The Disturbed ISM of the Local Group Dwarf Galaxy NGC 6822


  We present a wide-field, high spatial and velocity resolution map of the
entire extended HI distribution of the nearby Local Group dwarf galaxy NGC
6822. The observations were obtained with the Parkes single-dish telescope and
the Australia Telescope Compact Array in mosaicing mode. NGC 6822 has an
extended HI-disk which is shaped by the presence of numerous HI holes and
shells, including a supergiant shell, and the effects of tidal interaction, in
the form of a tidal arm and an infalling or interacting HI complex. These tidal
features are not obvious in lower resolution data, and only the proximity of
NGC 6822 enables us to see them clearly. This suggests that the importance of
minor interactions in dwarf galaxies may be larger than previously assumed.

</DOC>
<DOC>
<DOCNO> 116946 </DOCNO>
Reliability History and Improvements to the ANL 50 MEV H- Accelerator


  The H- Accelerator consists of a 750 keV Cockcroft Walton preaccelerator and
an Alvarez type 50 MeV linac. The accelerator has been in operation since 1961.
Since 1981, it has been used as the injector for the Intense Pulsed Neutron
Source (IPNS), a national user facility for neutron scattering. The linac
delivers about 3.5x1012 H- ions per pulse, 30 times per second (30 Hz), for
multi-turn injection to a 450 MeV Rapid Cycling Synchrotron (RCS). IPNS
presently operates about 4,000 hours per year, and operating when scheduled is
critical to meeting the needs of the user community. For many years the IPNS
injector/RCS has achieved an average reliability of 95%, helped in large part
by the preaccelerator/linac which has averaged nearly 99%. To maintain and
improve system reliability, records need to show what each subsystem
contributes to the total down time. The history of source and linac subsystem
reliability, and improvements that have been made to improve reliability, will
be described. Plans to maintain or enhance this reliability for at least
another ten years of operation, will also be discussed.

</DOC>
<DOC>
<DOCNO> 70112 </DOCNO>
Bound-state effects in \mu^+ e^- \to \gamma\gamma and \bar{B}^{0}_s \to


  We demonstrate that in the double-radiative decays of heavy-light QED and QCD
atoms, \mu^{+} e^{-} \to \gamma\gamma and \bar{B}^{0}_{s} \to \gamma\gamma,
there is a contribution coming from operators that vanish on the free-quark
mass shell. This off-shell effect is suppressed with respect to the effect of
the well known flavour-changing magnetic-moment operator by the bound-state
binding factor. Accordingly, the negligible off-shellness of the weakly bound
QED atoms becomes important for strongly bound QCD atoms. We present this
effect in two different model-approaches to QCD, one of them enabling us to
keep close contact to the related effect in QED.

</DOC>
<DOC>
<DOCNO> 118118 </DOCNO>
The Fading of Supernova Remnant Cassiopeia A from 38 MHz to 16.5 GHz


  We report 1405 MHz measurements of the flux density of the approximately 320
year old supernova remnant Cassiopeia A, relative to the flux density of Cygnus
A, made between 1995 and 1999. When compared to measurements made between 1957
and 1976, we find that the rate at which Cassiopeia A has been fading at this
and nearby frequencies has changed from approximately 0.9 % yr^-1 in the 1960s
to approximately 0.6 - 0.7 % yr^-1 now. Furthermore, we have collected from the
literature measurements of this fading rate at lower (38 - 300 MHz) and higher
(7.8 - 16.5 GHz) frequencies. We show that the fading rate has dropped by a
factor of approximately 3 over the past 50 years at the lower frequencies,
while remaining relatively constant at the higher frequencies, which is in
agreement with the findings of others. Our findings at 1405 MHz, in conjunction
with a measurement of the fading rate at the nearby frequency of 927 MHz by
Vinyajkin (1997), show an intermediate behavior at intermediate frequencies. We
also find that Cassiopeia A, as of approximately 1990, was fading at about the
same rate, approximately 0.6 - 0.7 % yr^-1, at all of these frequencies. Future
measurements are required to determine whether the fading rate will continue to
decrease at the lower frequencies, or whether Cassiopeia A will now fade at a
relatively constant rate at all of these frequencies.

</DOC>
<DOC>
<DOCNO> 118203 </DOCNO>
The VizieR database of Astronomical Catalogues


  VizieR is a database grouping in an homogeneous way thousands of astronomical
catalogues gathered since decades by the Centre de Donnees de Strasbourg (CDS)
and participating institutes. The history and current status of this large
collection is briefly presented, and the way these catalogues are being
standardized to fit in the VizieR system is described. The architecture of the
database is then presented, with emphasis on the management of links and of
accesses to very large catalogues. Several query interfaces are currently
available, making use of the ASU protocol, for browsing purposes or for use by
other data processing systems such as visualisation tools.

</DOC>
<DOC>
<DOCNO> 152068 </DOCNO>
A new AdS/CFT correspondence


  We consider a geometric zero-radius limit for strings on $AdS_5\times S^5$,
where the anti-de Sitter hyperboloid becomes the projective lightcone. In this
limit the fifth dimension becomes nondynamical, yielding a different
"holographic" interpretation than the usual "bulk to boundary" one. When
quantized on the random lattice, the fifth coordinate acts as a new kind of
Schwinger parameter, producing Feynman rules with normal propagators at the
tree level: For example, in the bosonic case ordinary massless $\phi^4$ theory
is obtained. In the superstring case we obtain new, manifestly ${\cal N}=4$
supersymmetric rules for ${\cal N}=4$ super Yang-Mills. These gluons are also
different from those of the usual AdS/CFT correspondence: They are the
"partons" that make up the usual "hadrons" of the open and closed strings in
the familiar QCD string picture. Thus, their coupling $g_{YM}$ and rank $N$ of
the "color" gauge group are different from those of the "flavor" gauge group of
the open string. As a result we obtain different perturbation expansions in
radius, coupling, and 1/N.

</DOC>
<DOC>
<DOCNO> 102431 </DOCNO>
Polygon Recognition and Symmetry Detection


  We introduce an approach based on moving frames for polygon recognition and
symmetry detection. We present detailed algorithms for recognition of polygons
modulo the special Euclidean, Euclidean, equi-affine, skewed-affine and
similarity Lie groups, and explain the procedure for a generic Lie group. The
time complexity of our algorithms is linear in the number of vertices and they
are noise resistant. The signatures used allow the detection of partial as well
as approximate equivalences. Our method is a particular case of a general
method for curve recognition modulo Lie group action.

</DOC>
<DOC>
<DOCNO> 9082 </DOCNO>
Anderson-type model for a molecule adsorbed on a metal surface


  We investigate a modified Anderson model to study the local density of states
(LDOS) of a molecular wire adsorbed on a metal. Using a self-consistent
mean-field type approach we find an exponential decay of the LDOS along the
molecule. A repulsive on-site interaction on the molecule suppresses the
tunneling and decreases the characteristic decay length.

</DOC>
<DOC>
<DOCNO> 150510 </DOCNO>
Thick domain walls and singular spaces


  We discuss thick domain walls interpolating between spaces with naked
singularities and give arguments based on the $AdS$/CFT correspondence why such
singularities may be physically meaningful. Our examples include thick domain
walls with Minkowski, de Sitter, and anti-de Sitter geometries on the
four-dimensional slice. For flat domain walls we can solve the equivalent
quantum mechanics problem exactly, which provides the spectrum of graviton
states. In one of the examples we discuss, the continuum states have a mass
gap. We compare the graviton spectra with expectations from the $AdS$/CFT
correspondence and find qualitative agreement. We also discuss unitary boundary
conditions and show that they project out all continuum states.

</DOC>
<DOC>
<DOCNO> 120887 </DOCNO>
Fast Convolution on the Sphere


  We propose fast, exact and efficient algorithms for the convolution of two
arbitrary functions on the sphere which speed up computations by a factor
\order{\sqrt{N}} compared to present methods where $N$ is the number of pixels.
No simplifying assumptions are made other than bandlimitation. This reduces
typical computation times for convolving the full sky with the asymmetric beam
pattern of a megapixel Cosmic Microwave Background (CMB) mission from months to
minutes. Our methods enable realistic simulation and careful analysis of data
from such missions, taking into account the effects of asymmetric ``point
spread functions'' and far side lobes of the physical beam. While motivated by
CMB studies, our methods are general and hence applicable to the convolution or
filtering of any scalar field on the sphere with an arbitrary, asymmetric
kernel. We show in an appendix that the same ideas can be applied to the
inverse problems of map-making and beam reconstruction by similarly
accelerating the {\em transpose convolution} which is needed for the iterative
solution of the normal equations.

</DOC>
<DOC>
<DOCNO> 9747 </DOCNO>
Scaling of crossing probabilities for the q-state Potts model at


  We present study of finite-size scaling and universality of crossing
probabilities for the $q$-state Potts model. Crossing probabilities of the
Potts model are similar ones in percolation problem. We numerically
investigated scaling of $\pi_{s}$ - the probability of a system to percolate
only in one direction for two-dimensional site percolation, the Ising model,
and the q-state Potts model for $q=3,4,5,6,8,10$. We found the thermal scaling
index $y= \frac{1}{\nu}$ for $q<4$. In contrast, $y \ne \frac{1}{\nu}$ for
$q=4$.

</DOC>
<DOC>
<DOCNO> 85421 </DOCNO>
Resampled random processes in gravitational-wave data analysis


  The detection of continuous gravitational-wave signals requires to account
for the motion of the detector with respect to the solar system barycenter in
the data analysis. In order to search efficiently for such signals by means of
the fast Fourier transform the data needs to be transformed from the
topocentric time to the barycentric time by means of resampling. The resampled
data form a non-stationary random process. In this communication we prove that
this non-stationary random process is mathematically well defined, and show
that generalizations of the fundamental results for stationary processes, like
Wiener-Khintchine theorem and Cram\`{e}r representation, exist.

</DOC>
<DOC>
<DOCNO> 101026 </DOCNO>
Singularities of variations of mixed Hodge structure


  We prove that a variation of graded-polarizable mixed Hodge structure over a
punctured disk with unipotent monodromy, has a limiting mixed Hodge structure
at the puncture (i.e., it is admissible in the sense of [SZ]) which splits over
$\R$, if and only if certain grading of the complexified weight filtration,
depending smoothly on the Hodge filtration, extends across the puncture. In
particular, the result exactly supplements Schmid's Theorem for pure
structures, which holds for the graded variation, and gives a Hodge-theoretic
condition for the relative monodromy weight filtration to exist.

</DOC>
<DOC>
<DOCNO> 12893 </DOCNO>
Geometry dominated fluid adsorption on sculptured substrates


  Experimental methods allow the shape and chemical composition of solid
surfaces to be controlled at a mesoscopic level. Exposing such structured
substrates to a gas close to coexistence with its liquid can produce quite
distinct adsorption characteristics compared to that occuring for planar
systems, which may well play an important role in developing technologies such
as super-repellent surfaces or micro-fluidics. Recent studies have concentrated
on adsorption of liquids at rough and heterogeneous substrates and the
characterisation of nanoscopic liquid films. However, the fundamental effect of
geometry has hardly been addressed. Here we show that varying the shape of the
substrate can exert a profound influence on the adsorption isotherms allowing
us to smoothly connect wetting and capillary condensation through a number of
novel and distinct examples of fluid interfacial phenomena. This opens the
possibility of tailoring the adsorption properties of solid substrates by
sculpturing their surface shape.

</DOC>
<DOC>
<DOCNO> 151359 </DOCNO>
On the quantum BRST structure of classical mechanics


  The BRST-antiBRST invariant path integral formulation of classical mechanics
of Gozzi et al is generalized to pseudomechanics. It is shown that projections
to physical propagators may be obtained by BRST-antiBRST invariant boundary
conditions. The formulation is also viewed from recent group theoretical
results within BRST-antiBRST invariant theories. A natural bracket expressed in
terms of BRST and antiBRST charges in the extended formulation is shown to be
equal to the Poisson bracket. Several remarks on the operator formulation are
made.

</DOC>
<DOC>
<DOCNO> 121509 </DOCNO>
Morphological classification of high redshift galaxies


  We present GASPHOT, a tool for automated surface photometry and morphological
classification of galaxies in deep and wide fields. The requirements for any
such tool are reviewed, and its use for the classification of high-z galaxies
is presented. In the case if HDF-like images, for galaxies having a magnitude
ranging from 24 to 27.5, the uncertainties on the photometric parameters
derived from GASPHOT are respectively 0.02-0.1 on magnitude, 0.03 on the
logarithm of the scale length, 0.02-0.5 on the Sersic index n used to classify
the surface brightness profile of the galaxies. A comparison with the results
achieved using Sextractor is presented.

</DOC>
<DOC>
<DOCNO> 7689 </DOCNO>
Dynamics of Collapse of flexible Polyelectrolytes and Polyampholytes


  We provide a theory for the dynamics of collapse of strongly charged
polyelectrolytes (PEs) and flexible polyampholytes (PAs) using Langevin
equation. After the initial stage, in which counterions condense onto PE, the
mechanism of approach to the globular state is similar for PE and PA. In both
instances, metastable pearl-necklace structures form in characteristic time
scale that is proportional to N^{4/5} where N is the number of monomers. The
late stage of collapse occurs by merger of clusters with the largest one
growing at the expense of smaller ones (Lifshitz- Slyozov mechanism). The time
scale for this process T_{COLL} N. Simulations are used to support the proposed
collapse mechanism for PA and PE.

</DOC>
<DOC>
<DOCNO> 9711 </DOCNO>
Comment on "The Transition Temperature of the Dilute Interacting Bose


  It is pointed out that first, contrary to the claim by Baym et al.[Phys. Rev.
Lett 83, 1703 (1999)], the shift in the transition temperature of a weakly
interacting Bose gas can be calculated perturbatively. And second, that the
regime considered by Huang [Phys. Rev. Lett 83, 3770 (1999)] while addressing
the same issue does not describe the Bose-Einstein condensed phase.

</DOC>
<DOC>
<DOCNO> 9120 </DOCNO>
II. Territory covered by N random walkers on stochastic fractals. The


  The average number $S_N(t)$ of distinct sites visited up to time t by N
noninteracting random walkers all starting from the same origin in a disordered
fractal is considered. This quantity $S_N(t)$ is the result of a double
average: an average over random walks on a given lattice followed by an average
over different realizations of the lattice. We show for two-dimensional
percolation clusters at criticality (and conjecture for other stochastic
fractals) that the distribution of the survival probability over these
realizations is very broad in Euclidean space but very narrow in the chemical
or topological space. This allows us to adapt the formalism developed for
Euclidean and deterministic fractal lattices to the chemical language, and an
asymptotic series for $S_N(t)$ analogous to that found for the non-disordered
media is proposed here. The main term is equal to the number of sites (volume)
inside a ``hypersphere'' in the chemical space of radius $L [\ln (N)/c]^{1/v}$
where L is the root-mean-square chemical displacement of a single random
walker, and v and c determine how fast $1-\Gamma_t(\ell)$ (the probability that
a given site at chemical distance $\ell$ from the origin is visited by a single
random walker by time t) decays for large values of $\ell/L$:
$1-\Gamma_t(\ell)\sim \exp[-c(\ell/L)^v]$. The parameters appearing in the
first two asymptotic terms of $S_N(t)$ are estimated by numerical simulation
for the two-dimensional percolation cluster at criticality. The corresponding
theoretical predictions are compared with simulation data, and the agreement is
found to be very good.

</DOC>
<DOC>
<DOCNO> 119417 </DOCNO>
Timescales of disk evolution and planet formation


  We present high-spatial resolution HST and adaptive optics observations, and
high-sensitivity ISO (ISOCAM & ISOPHOT) observations of a sample of X-ray
selected weak-line (WTTS) and post (PTTS) T Tauri stars located in the nearby
Chamaeleon T and Scorpius-Centaurus OB associations. HST/NICMOS and adaptive
optics observations aimed at identifying substellar companions at separations
>=30 A.U. from the primary stars. No such objects were found within 300 A.U. of
any of the target stars, and a number of faint objects at larger separations
can very likely be attributed to a population of background stars. ISOCAM
observations of 5 to 15 Myr old WTTS and PTTS in ScoCen reveal infrared
excesses which are clearly above photospheric levels, and which have a spectral
index intermediate between that of younger (1 to 5 Myr) T Tauri stars in Cha
and that of pure stellar photospheres. The difference in the spectral index of
the older PTTS in ScoCen compared to the younger classical and WTTS in Cha can
be attributed to a deficiency of smaller size (0.1 to 1mu) dust grains relative
to larger size (~5mu) dust grains in the disks of the PTTS. The lack of small
dust grains is either due to the environment (effect of nearby O stars and
supernova explosions) or due to disk evolution. If the latter is the case, it
would hint that circumstellar disks start to get dust depleted at an age
between 5 to 15 Myr. Dust depletion is very likely related to the build-up of
larger particles (ultimately rocks and planetesimals) and thus an indicator for
the onset of the period of planet formation.

</DOC>
<DOC>
<DOCNO> 83220 </DOCNO>
Centroid-based summarization of multiple documents: sentence extraction,


  We present a multi-document summarizer, called MEAD, which generates
summaries using cluster centroids produced by a topic detection and tracking
system. We also describe two new techniques, based on sentence utility and
subsumption, which we have applied to the evaluation of both single and
multiple document summaries. Finally, we describe two user studies that test
our models of multi-document summarization.

</DOC>
<DOC>
<DOCNO> 99528 </DOCNO>
Lattice Substitution Systems and Model Sets


  The paper studies ways in which the sets of a partition of a lattice in
$\RR^n$ become regular model sets. The main theorem gives equivalent conditions
which assure that a matrix substitution system on a lattice in $\RR^n$ gives
rise to regular model sets (based on $p$-adic-like internal spaces), and hence
to pure point diffractive sets. The methods developed here are used to show
that the $n-$dimensional chair tiling and the sphinx tiling are pure point
diffractive.

</DOC>
<DOC>
<DOCNO> 178961 </DOCNO>
Electromagnetic Dissociation as a Tool for Nuclear Structure and


  Coulomb dissociation is an especially simple and important reaction
mechanism. Since the perturbation due to the electric field of the nucleus is
exactly known, firm conclusions can be drawn from such measurements.
Electromagnetic matrix elements and astrophysical S-factors for radiative
capture processes can be extracted from experiments. We describe the basic
theory, new results concerning higher order effects in the dissociation of
neutron halo nuclei, and briefly review the experimental results obtained up to
now. Some new applications of Coulomb dissociation for nuclear astrophysics and
nuclear structure physics are discussed.

</DOC>
<DOC>
<DOCNO> 117405 </DOCNO>
A limit-cycle model for the binary supersoft X-ray source RX


  We present new results of our X-ray monitoring of the transient binary
supersoft X-ray source RX J0513.9-6951 in the LMC and of our re-analysis of
optical light curves obtained during the MACHO project. We have covered a
complete X-ray outburst cycle with the ROSAT HRI detector. From the amplitude
and timescale of the soft X-ray variability, tight limits are derived for the
temporal behaviour of the white-dwarf radius and the effective temperature of
its envelope. A limit-cycle model is proposed to explain the observed optical
and X-ray variability, the characteristic timescales of the durations of the
X-ray on and off states, and those of the transitions between both states. Our
observations confirm that the radius changes of the white-dwarf envelope occur
on the Kelvin-Helmholtz timescale. The duration of the X-ray on and off states
is compatible with the viscous timescales of the inner and outer accretion
disk, respectively.

</DOC>
<DOC>
<DOCNO> 70823 </DOCNO>
Graviton Production in Relativistic Heavy-Ion Collisions


  We study the feasibility of producing the graviton of the novel Kaluza-Klein
theory in which there are d large compact dimensions in addition to the 4
dimensions of Minkowski spacetime. We calculate the cross section for producing
such a graviton in nucleus-nucleus collisions via t-channel photon-photon
fusion using the semiclassical Weizsacker-Williams method and show that it can
exceed the cross section for graviton production in electron-positron
scattering by several orders of magnitude.

</DOC>
<DOC>
<DOCNO> 116441 </DOCNO>
XAFS spectroscopy. II. Statistical evaluations in the fitting problems


  The problem of error analysis is addressed in stages beginning with the case
of uncorrelated parameters and proceeding to the Bayesian problem that takes
into account all possible correlations when a great deal of prior information
about the accessible parametr space is available. The formulas for the standard
deviations and deviations with arbitrary confidence levels are derived.
Underestimation of the errors of XAFS-function extraction is shown to be a
source of unjustified optimistic errors of fitting parameters. The applications
of statistical chi^2- and F-tests to the fitting problems are also discussed.

</DOC>
<DOC>
<DOCNO> 119691 </DOCNO>
A project of a new detector for direct Dark Matter search: MACHe3


  MACHe3 (MAtrix of Cells of superfluid He3) is a project of a new detector for
direct Dark Matter (DM) search. A cell of superfluid He3 has been developed and
the idea of using a large number of such cells in a high granularity detector
is proposed.This contribution presents, after a brief description of the
superfluid He3 cell, the simulation of the response of different matrix
configurations allowing to define an optimum design as a function of the number
of cells and the volume of each cell. The exclusion plot and the predicted
interaction cross-section for the neutralino as a photino are presented.

</DOC>
<DOC>
<DOCNO> 102677 </DOCNO>
Ample families, multihomogeneous spectra, and algebraization of formal


  Generalizing homogeneous spectra for rings graded by natural numbers, we
introduce multihomogeneous spectra for rings graded by abelian groups. Such
homogeneous spectra have the same completeness properties as their classical
counterparts, but are possibly nonseparated. We relate them to ample families
of invertible sheaves and simplicial toric varieties. As an application, we
generalize Grothendieck's Algebraization Theorem and show that formal schemes
with certain ample families are algebraizable.

</DOC>
<DOC>
<DOCNO> 100669 </DOCNO>
Distinguished properties of the gamma process and related topics


  We study fundamental properties of the gamma process and their relation to
various topics such as Poisson-Dirichlet measures and stable processes. We
prove the quasi-invariance of the gamma process with respect to a large group
of linear transformations. We also show that it is a renormalized limit of the
stable processes and has an equivalent sigma-finite measure (quasi-Lebesgue)
with important invariance properties. New properties of the gamma process can
be applied to the Poisson-Dirichlet measures. We also emphasize the deep
similarity between the gamma process and the Brownian motion. The connection of
the above topics makes more transparent some old and new facts about stable and
gamma processes, and the Poisson-Dirichlet measures.

</DOC>
<DOC>
<DOCNO> 121417 </DOCNO>
The effect of a cusped matter distribution on the formation of brightest


  We present N-body simulations of galaxy groups embedded in a common halo of
matter. We study the influence of the different initial conditions upon the
evolution of the group and show that denser configurations evolve faster, as
expected. We then concentrate on the influence of the initial radial density
profile of the common halo and of the galaxy distribution. We select two kinds
of density distributions, a singular profile (modeled by a Hernquist
distribution) and a profile with a flat core (modeled by a Plummer sphere). In
all cases we witness the formation of a central massive object due to mergings
of individual galaxies and to accretion of stripped material, but both its
formation history and its properties depend heavily on the initial
distribution. In Hernquist models the formation is due to a ``burst'' of
mergings in the inner parts, due to the large initial concentration of galaxies
in the center. The merging rate is much slower in the initial phases of the
evolution of a Plummer distribution, where the contribution of accretion to the
formation of the central object is much more important. The central objects
formed within Plummer distributions have projected density profiles which are
not in agreement with the radial profiles of observed brightest cluster
members, unless the percentage of mass in the common halo is small. On the
contrary the central object formed in initially cusped models has projected
radial profiles in very good agreement with those of brightest cluster members,
sometimes also showing luminosity excess over the $r^{1/4}$ law in the outer
parts, as is observed in cD galaxies.

</DOC>
<DOC>
<DOCNO> 7819 </DOCNO>
Random Walk Beyond Hartree-Fock


  We give a brief discussion of the recently developed Constrained-Path Monte
Carlo Method. This method is a quantum Monte Carlo technique that eliminates
the fermion sign problem plaguing simulations of systems of interacting
electrons. The elimination is accomplished by trading an exact procedure for an
approximate one that has been demonstrated to give very accurate estimates of
energies and many-body correlation functions. We also give a short review of
its applications, a discussion of several strategies for parallelizing it, and
some speculation of its future extensions.

</DOC>
<DOC>
<DOCNO> 9012 </DOCNO>
Field induced ordering in highly frustrated antiferromagnets


  We predict that an external field can induce a spin order in highly
frustrated classical Heisenberg magnets. We find analytically stabilization of
collinear states by thermal fluctuations at a one-third of the saturation field
for kagome and garnet lattices and at a half of the saturation field for
pyrochlore and frustrated square lattices. This effect is studied numerically
for the frustrated square-lattice antiferromagnet by Monte Carlo simulations
for classical spins and by exact diagonalization for $S=1/2$. The field induced
collinear states have a spin gap and produce magnetization plateaus.

</DOC>
<DOC>
<DOCNO> 39629 </DOCNO>
A partial wave analysis of the $\pi ^0\pi ^0$ system produced in $\pi


  A partial wave analysis of the of the $\pi ^0\pi ^0$ system produced in the
charge exchange reaction: $\pi ^-p\to \pi ^0\pi ^0n$ at an incident momentum of
$18.3 GeV/c$ is presented as a function of ${\pi ^0\pi ^0}$ invariant mass,
$m_{\pi^0\pi^0}$, and momentum transfer squared, $| {t} |$, from the incident
$\pi^-$ to the outgoing ${\pi ^0\pi ^0}$ system.

</DOC>
<DOC>
<DOCNO> 71336 </DOCNO>
The prompt lepton cookbook


  We review the calculation of the prompt lepton flux, produced in the
atmosphere by the semileptonic decay of charmed particles. We describe side by
side the intermediary ingredients used by different authors, which include not
only the charm production model, but also other atmospheric particle showering
parameters. After evaluating separately the relevance of each single
ingredient, we analyze the effect of different combinations over the final
result. We highlight the impact of the prompt lepton flux calculation upon
high-energy neutrino telescopes.

</DOC>
<DOC>
<DOCNO> 100621 </DOCNO>
On the definition of geometric Dirac operators


  In this largely expository paper we give a self-contained treatment of the
Dirac operator. Emphasizing the algebraic point of view we first sketch the
necessary prerequisites from Clifford algebras and their representations and
then define (and characterize) spin structures and the corresponding Spin-Dirac
operator purely in the spirit of irreducible representations. We also prove its
equivalence with the usual approach via principal bundles. We conclude with
other geometric Dirac operators and their properties using the afore-mentioned
setting.

</DOC>
<DOC>
<DOCNO> 70771 </DOCNO>
Top Mass Measurement and Bottom Fragmentation at the LHC


  We show some recent HERWIG results related to the top quark mass measurement
at the LHC and discuss possible improvements for studies of the bottom quark
fragmentation function in the top decay.

</DOC>
<DOC>
<DOCNO> 151796 </DOCNO>
Geometric Properties of QCD String From Willmore Functional


  The extremum of the Willmore-like functional for $m$-dimensional Riemannian
surface immersed in $d$-dimensional Riemannian manifold under normal variations
is studied and various cases of interest are examined. This study is used to
relate the parameters of QCD string action, including the Polyakov-Kleinert
extrinsic curvature action, with the geometric properties of the world sheet.
The world sheet has been shown to have {\it{negative stiffness}} on the basis
of geometric considerations.

</DOC>
<DOC>
<DOCNO> 9526 </DOCNO>
Two-magnon Raman scattering in spin-ladder geometries and the ratio of


  We discuss ways in which the ratio of exchange constants along the rungs and
legs of a spin-ladder material influences the two-magnon Raman scattering
spectra and hence can be determined from it. We show that within the
Fleury-Loudon-Elliott approach, the Raman line-shape does not change with
polarization geometries. This lineshape is well known to be difficult to
calculate accurately from theory. However, the Raman scattering intensities do
vary with polarization geometries, which are easy to calculate. With some
assumptions about the Raman scattering Hamiltonian, the latter can be used to
estimate the ratio of exchange constants. We apply these results to Sugai's
recent measurements of Raman scattering from spin-ladder materials such as
La$_6$Ca$_8$Cu$_{24}$O$_{41}$ and Sr$_{14}$Cu$_{24}$O$_{41}$.

</DOC>
<DOC>
<DOCNO> 12509 </DOCNO>
Universal finite-size scaling amplitudes in anisotropic scaling


  Phenomenological scaling arguments suggest the existence of universal
amplitudes in the finite-size scaling of certain correlation lengths in
strongly anisotropic or dynamical phase transitions. For equilibrium systems,
provided that translation invariance and hyperscaling are valid, the
Privman-Fisher scaling form of isotropic equilibrium phase transitions is
readily generalized. For non-equilibrium systems, universality is shown
analytically for directed percolation and is tested numerically in the
annihilation-coagulation model and in the pair contact process with diffusion.
In these models, for both periodic and free boundary conditions, the
universality of the finite-size scaling amplitude of the leading relaxation
time is checked. Amplitude universality reveals strong transient effects along
the active-inactive transition line in the pair contact process.

</DOC>
<DOC>
<DOCNO> 118718 </DOCNO>
Lithium-6 from Solar Flares


  By introducing a hitherto ignored Li-6 producing process, due to accelerated
He-3 reactions with He-4, we show that accelerated particle interactions in
solar flares produce much more Li-6 than Li-7. By normalizing our calculations
to gamma-ray data we demonstrate that the Li-6 produced in solar flares,
combined with photospheric Li-7, can account for the recently determined solar
wind lithium isotopic ratio, obtained from measurements in lunar soil, provided
that the bulk of the flare produced lithium is evacuated by the solar wind.
Further research in this area could provide unique information on a variety of
problems, including solar atmospheric transport and mixing, solar convection
and the lithium depletion issue, and solar wind and solar particle
acceleration.

</DOC>
<DOC>
<DOCNO> 118200 </DOCNO>
The role of electron-screening deformations in solar nuclear fusion


  Thermonuclear fusion reaction rates in the solar plasma are enhanced by the
presence of the electron cloud that screens fusing nuclei. The present work
studies the influence of electron screening deformations on solar reaction
rates in the framework of the Debye-Huckel model. These electron-ion cloud
deformations, assumed here to be static and axially symmetric, are shown to be
able to considerably influence the solar neutrino fluxes of the pp and the CNO
chains, with reasonable changes in the macroscopic parameters of the standard
solar model (SSM) . Various known deformation sources are discussed but none of
them is found strong enough to have a significant impact on the SSM neutrino
fluxes.

</DOC>
<DOC>
<DOCNO> 102681 </DOCNO>
Une infinite de structures de contact tendues sur les varietes


  We show that every closed toroidal irreducible orientable 3-manifold carries
infinitely many universally tight contact structures.

</DOC>
<DOC>
<DOCNO> 13203 </DOCNO>
Bilayer Quantum Hall States at $\nu=1$ and Coulomb Drag


  We consider a number of strongly-correlated quantum Hall states which are
likely to be realized in bilayer quantum Hall systems at total Landau level
filling fraction ${\nu_T}=1$. One state, the $(3,3,-1)$ state, can occur as an
instability of a compressible state in the large $d/l_B$ limit, where $d$ and
$l_B$ are the interlayer distance and magnetic length, respectively. This state
has a hierarchical descendent which is interlayer coherent. Another interlayer
coherent state, which is expected in the small $d/l_B$ limit is the well-known
Halperin $(1,1,1)$ state. Using the concept of composite fermion pairing, we
discuss the wavefunctions which describe these states. We construct a phase
diagram using the Chern-Simons Landau-Ginzburg theory and discuss the
transitions between the various phases. We propose that the longitudinal and
Hall drag resistivities can be used together with interlayer tunneling to
experimentally distinguish these different quantum Hall states. Our work
indicates the bilayer ${\nu_T}=1$ quantum Hall phase diagram to be considerably
richer than that assumed so far in the literature.

</DOC>
<DOC>
<DOCNO> 70886 </DOCNO>
Enhanced Direct CP Violation in $B^{\pm} \to \rho^{0} \pi^{\pm}$


  We study direct CP violation in the hadronic decay $B^{\pm} \to
\rho^{0}\pi^{\pm}$, including the effect of $\rho - \omega$ mixing. We find
that the CP violating asymmetry is strongly dependent on the CKM matrix
elements, especially the Wolfenstein parameter $\eta$. For fixed $N_{c}$ (the
effective parameter associated with factorization), the CP violating asymmetry,
$a$, has a maximum of order $30%-50%$ when the invariant mass of the
$\pi^{+}\pi^{-}$ pair is in the vicinity of the $\omega$ resonance. The
sensitivity of the asymmetry, $a$, to $N_{c}$ is small. Moreover, if $N_{c}$ is
constrained using the latest experimental branching ratios from the CLEO
collaboration, we find that the sign of $\sin \delta$ is always positive. Thus,
a measurement of direct CP violation in $B^{\pm} \to \rho^{0}\pi^{\pm}$ would
remove the mod$(\pi)$ ambiguity in ${\rm arg}[ -
\frac{V_{td}V_{tb}^{\star}}{V_{ud}V_{ub}^{\star}}]$.

</DOC>
<DOC>
<DOCNO> 100455 </DOCNO>
A generalization of Gordon's theorem and applications to quasiperiodic


  We prove a criterion for absence of eigenvalues for one-dimensional
Schr\"odinger operators. This criterion can be regarded as an $L^1$-version of
Gordon's theorem and it has a broader range of application. Absence of
eigenvalues is then established for quasiperiodic potentials generated by
Liouville frequencies and various types of functions such as step functions,
H\"older continuous functions and functions with power-type singularities. The
proof is based on Gronwall-type a priori estimates for solutions of
Schr\"odinger equations.

</DOC>
<DOC>
<DOCNO> 100511 </DOCNO>
The fourth tautological group of $\bar{\mathcal{M}_{g,n}}$ and relations


  We give a complete description of the tautological subgroup of the fourth
cohomology group of the moduli space of pointed stable curves, and prove that
for g \geq 8 it coincides with the cohomology group itself. We further give a
conjectural upper bound depending on the genus for the degree of new
tautological relations.

</DOC>
<DOC>
<DOCNO> 10025 </DOCNO>
Analytical results for a trapped, weakly-interacting Bose-Einstein


  We examine the problem of a repulsive, weakly-interacting and harmonically
trapped Bose-Einstein condensate under rotation. We derive a simple analytic
expression for the energy incorporating the interactions when the angular
momentum per particle is between zero and one and find that the interaction
energy decreases linearly as a function of the angular momentum in agreement
with previous numerical and limiting analytical studies.

</DOC>
<DOC>
<DOCNO> 84916 </DOCNO>
Gravitational collapse in 2+1 dimensional AdS spacetime


  We present results of numerical simulations of the formation of black holes
from the gravitational collapse of a massless, minimally-coupled scalar field
in 2+1 dimensional, axially-symmetric, anti de-Sitter (AdS) spacetime. The
geometry exterior to the event horizon approaches the BTZ solution, showing no
evidence of scalar `hair'. To study the interior structure we implement a
variant of black-hole excision, which we call singularity excision. We find
that interior to the event horizon a strong, spacelike curvature singularity
develops. We study the critical behavior at the threshold of black hole
formation, and find a continuously self-similar solution and corresponding
mass-scaling exponent of approximately 1.2. The critical solution is universal
to within a phase that is related to the angle deficit of the spacetime.

</DOC>
<DOC>
<DOCNO> 102412 </DOCNO>
Compressing totally geodesic surfaces


  In this paper we prove that one can find surgeries arbitrarily close to
infinity in the Dehn surgery space of the figure eight knot complement for
which some immersed totally geodesic surface compresses.

</DOC>
<DOC>
<DOCNO> 40157 </DOCNO>
Prompt Photons in Photoproduction at HERA


  First inclusive measurements of isolated prompt photons in photoproduction at
HERA have been made with the ZEUS detector. Cross sections are given as a
function of the pseudorapidity and the transverse energy of the photon, for
E_T^gamma > 5 GeV in the gamma-p centre-of-mass energy range 134-285 GeV.
Comparisons are made with predictions from LO Monte Carlo models and NLO QCD
calculations. For forward eta^gamma (proton direction) good agreement is found,
but in the rear direction all predictions fall below the data.

</DOC>
<DOC>
<DOCNO> 121187 </DOCNO>
Adaptive optics imaging of P Cygni in Halpha


  We obtained Halpha diffraction limited data of the LBV star P Cyg using the
ONERA Adaptive Optics (AO) facility BOA at the OHP 1.52m telescope on October
1997. Taking P Cyg and the reference star 59 Cyg AO long exposures we find that
P Cyg clearly exhibits a large and diffuse intensity distribution compared to
the 59 Cyg's point-like source. A deconvolution of P Cyg using 59 Cyg as the
Point Spread Function was performed by means of the Richardson-Lucy algorithm.
P Cyg clearly appears as an unresolved star surrounded by a clumped envelope.
The reconstructed image of P Cyg is compared to similar spatial resolution maps
obtained from radio aperture synthesis imaging. We put independent constraints
on the physics of P Cyg which agree well with radio results. We discuss future
possibilities to constrain the wind structure of P Cyg by using
multi-resolution imaging, coronagraphy and long baseline interferometry to
trace back its evolutionary status.

</DOC>
<DOC>
<DOCNO> 116420 </DOCNO>
Energy Balance in an Electrostatic Accelerator


  The principle of an electrostatic accelerator is that when a charge e escapes
from a conducting plane that supports a uniform electric field of strength E_0,
then the charge gains energy e E_0 d as it moves distance d from the plane.
Where does this energy come from? We that the mechanical energy gain of the
electron is balanced by the decrease in the electrostatic field energy of the
system.

</DOC>
<DOC>
<DOCNO> 118644 </DOCNO>
Dust properties of external galaxies; NGC 891 revisited


  We compare 850um SCUBA images of NGC 891 with the corresponding V-band
optical depth predicted from radiation transfer simulations. These two tracers
of dust show a very similar distribution along the minor axis and a reasonable
agreement along the major axis. Assuming that the grains responsible for
optical extinction are also the source of 850um emission we derive a
submillimeter emissivity (emission efficiency) for dust in the NGC 891 disk.
This quantity is found to be a factor of 2-3 higher than the generally-accepted
(but highly uncertain) values adopted for the Milky Way. It should be stated,
however, that if a substantial fraction of dust in NGC 891 is clumped, the
emissivity in the two galaxies may be quite similar. We use our newly-acquired
emissivity to convert our 850um images into detailed maps of dust mass and,
utilizing 21cm and CO-emission data for NGC 891, derive the gas-to-dust ratio
along the disk. We compute an average ratio of 260 -- a value consistent with
the Milky Way and external spirals within the uncertainties in deriving both
the dust mass and the quantity of molecular gas. The bulk of dust in NGC 891
appears to be closely associated with the molecular gas phase although it may
start to follow the distribution of atomic hydrogen at radii >9 kpc (i.e. >0.5
R_25). Using the optical depth of the NGC 891 disk, we quantify how light
emitted at high redshift is attenuated by dust residing in foreground spirals.
For B-band observations of galaxies typically found in the Hubble Deep Field,
the amount of light lost is expected to be small (~ 5%). This value depends
critically on the maximum radial extent of cold dust in spiral disks (which is
poorly known). It may also represent a lower limit if galaxies expel dust over
time into the intergalactic medium.

</DOC>
<DOC>
<DOCNO> 11302 </DOCNO>
Random field based model of mixed ferroelectrics phase diagram


  The equations for phase transitions temperatures, order parameters and
critical concentrations of components have been derived for mixed
ferroelectrics. The electric dipoles randomly distributed over the system were
considered as a random field sources. We derive a random field distribution
function for different orientations of the electric dipoles with nonlinear and
spatial correlation effects included.

</DOC>
<DOC>
<DOCNO> 84323 </DOCNO>
Horizon States for AdS Black Holes


  We study the time-independent modes of a massless scalar field in various
black hole backgrounds, and show that for these black holes, the
time-independent mode is localised at the horizon. A similar analysis is done
for time-independent equilibrium modes of the five dimensional plane AdS black
hole. A self-adjointness analysis of this problem reveals that in addition to
the modes corresponding to the usual glueball states, there is a discrete
infinity of other equilibrium modes with imaginary mass for the glueball. We
suggest these modes may be related to a Savvidy-Nielsen-Olesen-like vacuum
instability in QCD.

</DOC>
<DOC>
<DOCNO> 8128 </DOCNO>
From waves to avalanches: two different mechanisms of sandpile dynamics


  Time series resulting from wave decomposition show the existence of different
correlation patterns for avalanche dynamics. For the d=2 Bak-Tang-Wiesenfeld
model, long range correlations determine a modification of the wave size
distribution under coarse graining in time, and multifractal scaling for
avalanches. In the Manna model, the distribution of avalanches coincides with
that of waves, which are uncorrelated and obey finite size scaling, a result
expected also for the d=3 Bak et al. model.

</DOC>
<DOC>
<DOCNO> 85640 </DOCNO>
Second Variations of String Actions


  A short article describing the derivation of the string deviation equation:
$\dot{\Pi}^\nu_\tau+\Pi'^\mu_\sigma=R^\nu_{.\alpha\beta\gamma}r^\gamma
(P^\beta_\tau\dot{x}^\alpha+P^\beta_\sigma x'^\alpha)$.

</DOC>
<DOC>
<DOCNO> 70559 </DOCNO>
Constraints on $\gamma$ and Strong Phases from $B\to\pi K$ Decays


  As we pointed out recently, the neutral decays $B_d\to\pi^\mp K^\pm$ and
$B_d\to\pi^0K$ may provide non-trivial bounds on the CKM angle $\gamma$. Here
we reconsider this approach in the light of recent CLEO data, which look very
interesting. In particular, the results for the corresponding CP-averaged
branching ratios are in favour of strong constraints on $\gamma$, where the
second quadrant is preferred. Such a situation would be in conflict with the
standard analysis of the unitarity triangle. Moreover, constraints on a
CP-conserving strong phase $\delta_n$ are in favour of a negative value of
$\cos\delta_n$, which would be in conflict with the factorization expectation.
In addition, there seems to be an interesting discrepancy with the bounds that
are implied by the charged $B\to\pi K$ system: whereas these decays favour a
range for $\gamma$ that is similar to that of the neutral modes, they point
towards a positive value of $\cos\delta_c$, which would be in conflict with the
expectation of equal signs for $\cos\delta_n$ and $\cos\delta_c$.

</DOC>
<DOC>
<DOCNO> 122308 </DOCNO>
Implications of the Discovery of Millisecond Pulsar in SN 1987A


  From the observation of a millisecond pulsar in SN 1987A, the following
implications are obtained. 1) The pulsar spindown in SN 1987A is caused by
radiating gravitational waves rather than by magnetic dipole radiation and/or
relativistic pulsar winds. 2) A mildly deformed shock wave would be formed at
the core-collapse and explosion in SN 1987A, which is consistent with the
conclusion given in Nagataki (2000). 3) The gravitational waves from the pulsar
should be detected in several years using a Fabry-Perot-Michelson
interferometer as the gravitational detector, such as LIGO and TAMA. 4) The
neutrino oscillation model is not a promising model for the explanation of the
kick velocity of the pulsar in SN 1987A. The hydrodynamical instability model
is more favored.

</DOC>
<DOC>
<DOCNO> 119216 </DOCNO>
The Hamburg/ESO survey for bright QSOs. III. A large flux-limited sample


  We present a new sample of 415 bright QSOs and Seyfert~1 nuclei drawn from
the Hamburg/ESO survey (HES). The sample is spectroscopically 99 % complete and
well-defined in terms of flux and redshift limits. Optical magnitudes are in
the interval 13 < B_J < 17.5, redshifts range within 0< z < 3.2. More than 50 %
of the objects in the sample are new discoveries. We describe the selection
techniques and discuss sample completeness and potential selection effects.
There is no evidence for redshift-dependent variations of completeness; in
particular, low-redshift QSOs - notoriously missed by other optical surveys -
are abundant in this sample, since no discrimination against extended sources
is imposed. For the same reason, the HES is not biased against multiply imaged
QSOs due to gravitational lensing. The sample forms the largest homogeneous set
of bright QSOs currently in existence, useful for a variety of statistical
studies. We have redetermined the bright part of the optical quasar
number-magnitude relation. We confirm that the Palomar-Green survey is
significantly incomplete, but that its degree of incompleteness has recently
been overestimated.

</DOC>
<DOC>
<DOCNO> 117059 </DOCNO>
Automodulations in Kerr-lens Modelocked Solid-State Lasers


  Nonstationary pulse regimes associated with self modulation of a Kerr-lens
modelocked Ti:sapphire laser have been studied experimentally and
theoretically. Such laser regimes occur at an intracavity group delay
dispersion that is smaller or larger than what is required for stable
modelocking and exhibit modulation in pulse amplitude and spectra at
frequencies of several hundred kHz. Stabilization of such modulations, leading
to an increase in the pulse peak power by a factor of ten, were accomplished by
weakly modulating the pump laser with the self-modulation frequency. The main
experimental observations can be explained with a round trip model of the fs
laser taking into account gain saturation, Kerr lensing, and second- and
third-order dispersion.

</DOC>
<DOC>
<DOCNO> 40371 </DOCNO>
Search for B+ -> K+ l+ l- and B0 -> K*0 l+ l-


  Using a sample of 3.7 x 10^6$ Upsilon(4S) -> B Bbar events collected with the
BaBar detector at the PEP-II storage ring, we search for the electroweak
penguin decays B+ -> K+ e+ e-, B+ -> K+ mu+ mu-, B0 -> K*0 e+ e-, and B0 -> K*0
mu+ mu-. We observe no significant signals for these modes and set preliminary
90% C.L. upper limits of Br(B+ -> K+ e+ e-) < 12.5 x 10^(-6), Br(B+ -> K+ mu+
mu-) < 8.3 x 10^(-6), Br(B0 -> K*0 e+ e-) < 24.1 x 10^(-6), and Br(B0 -> K*0
mu+ mu-) < 24.5 x 10^(-6).

</DOC>
<DOC>
<DOCNO> 119966 </DOCNO>
A Near-Infrared L Band Survey of the Young Embedded Cluster NGC 2024


  We present the results of the first sensitive L band (3.4 micron) imaging
study of the nearby young embedded cluster NGC 2024. Two separate surveys of
the cluster were acquired in order to obtain a census of the circumstellar disk
fraction in the cluster. From an analysis of the JHKL colors of all sources in
our largest area, we find an infrared excess fraction of > 86%. The JHKL colors
suggest that the infrared excesses arise in circumstellar disks, indicating
that the majority of the sources which formed in the NGC 2024 cluster are
currently surrounded by, and likely formed with circumstellar disks. The excess
fractions remain very high, within the errors, even at the faintest L
magnitudes from our deeper surveys suggesting that disks form around the
majority of the stars in very young clusters such as NGC 2024 independent of
mass. From comparison with published JHKL observations of Taurus, we find the K
- L excess fraction in NGC 2024 to be consistent with a high initial incidence
of circumstellar disks in both NGC 2024 and Taurus. Because NGC 2024 represents
a region of much higher stellar density than Taurus, this suggests that disks
may form around most of the YSOs in star forming regions independent of
environment. We find a relatively constant JHKL excess fraction with increasing
cluster radius, indicating that the disk fraction is independent of location in
the cluster. In contrast, the JHK excess fraction increases rapidly toward the
central region of the cluster, and is most likely due to contamination of the K
band measurements by bright nebulosity in the central regions of the cluster.
We identify 45 candidate protostellar sources in the central regions of the NGC
2024 cluster, and find a lower limit on the protostellar phase of early stellar
evolution of 0.4 - 1.4 X 10^5 yr, similar to that in Taurus.

</DOC>
<DOC>
<DOCNO> 71354 </DOCNO>
Basis independent neutrino masses in the $R_p$ violating MSSM


  We calculate the neutrino mass matrix up to one loop order in the MSSM
without R-parity, including the bilinears in the mass insertion approximation.
This introduces additional diagrams usually neglected in the literature. We
systematically consider the possible new diagrams, and find a few missing from
our previous work. We provide analytic expressions for the mass matrix elements
in the neutrino flavour basis, which are independent of the $H_d - L_i$ basis
choice in the Lagrangian. We compare the contributions from different diagrams,
and make ``Lagrangian-basis-independent'' estimates of when the new diagrams
need to be included. We briefly discuss the phenomenology of a toy model of
bilinear R-parity violation.

</DOC>
<DOC>
<DOCNO> 101195 </DOCNO>
Classification of extremal elliptic K3 surfaces and fundamental groups


  We present a complete list of extremal elliptic K3 surfaces. There are
altogether 325 of them. The first 112 coincides with Miranda-Persson's list for
semi-stable ones. The data include the transcendental lattice which determines
uniquely the K3 surface by a result of Shioda and Inose, the singular fibre
type and the Mordell Weil group. As an application, we give a sufficient
condition for the topological fundamental group of complement to an
ADE-configuration of smooth rational curves on a K3 surface to be trivial.

</DOC>
<DOC>
<DOCNO> 40524 </DOCNO>
Higgs Candidates in e+e- Interactions at root(s) = 206.6 GeV


  In a search for the Standard Model Higgs boson, carried out on 212.5 pb-1 of
data collected by the L3 detector at the highest LEP centre-of-mass energies,
including 116.5 pb-1 above root(s) = 206GeV, an excess of candidates for the
process e+e- -> Z* -> HZ is found for Higgs masses near 114.5GeV. We present an
analysis of our data and the characteristics of our strongest candidates.

</DOC>
<DOC>
<DOCNO> 151742 </DOCNO>
Supergravity and Worldvolume Physics in the Dual Description of $\N=1^*$


  We look at the string theory dual of the $\N=1^*$ theory, involving
5--branes, which was recently proposed by Polchinski and Strassler
\cite{PolStr}. We argue that SUGRA alone is not enough in order to obtain the
correct screening and confinement behaviour of the various massive field theory
vacua, but that appropriate worldvolume phenomena of the 5--branes must be
included. We therefore work within the SUGRA approximation, also taking into
account the brane dynamics, and classify all the SUGRA configurations. In this
level of analysis, we find multiple valid configurations for every given
vacuum. We discuss some possible resolutions of this perplexing result. We also
consider the spectrum of asymptotic states, and discuss the global symmetries
of the SUGRA solution of the $\N=1^*$ theory and of the $\N=0^*$ theory
obtained from it by explicit supersymmetry breaking.

</DOC>
<DOC>
<DOCNO> 151778 </DOCNO>
On the Finiteness of the N=4 SUSY Nonlinear Sigma Model in Three


  We construct the {\cal N}=4 supersymmetric nonlinear sigma model in three
dimensions which can be expanded in 1/N. We evaluate the effective action at
leading order in the 1/N expansion and show the finiteness of the model to this
order.

</DOC>
<DOC>
<DOCNO> 101342 </DOCNO>
The Double and Dual of a Quasitriangular Lie Bialgebra


  Let G be a connected, simply connected Poisson-Lie group with quasitriangular
Lie bialgebra g. An explicit description of the double D(g) is given, together
with the embeddings of g and g^*. This description is then used to provide a
construction of the double D(G). The aim of this work is to describe D(G) in
sufficient detail to be able to apply the procedures of Semenov-Tian-Shansky
and Drinfeld for the classification of symplectic leaves and Poisson
homogeneous spaces for Poisson-Lie groups.

</DOC>
<DOC>
<DOCNO> 123122 </DOCNO>
On the minimum and maximum mass of neutron stars and the delayed


  The minimum and maximum mass of protoneutron stars and neutron stars are
investigated. The hot dense matter is described by relativistic (including
hyperons) and non-relativistic equations of state. We show that the minimum
mass ($\sim$ 0.88 - 1.28 $M_{\sun}$) of a neutron star is determined by the
earliest stage of its evolution and is nearly unaffected by the presence of
hyperons. The maximum mass of a neutron star is limited by the protoneutron
star or hot neutron star stage. Further we find that the delayed collapse of a
neutron star into a black hole during deleptonization is not only possible for
equations of state with softening components, as for instance, hyperons, meson
condensates etc., but also for neutron stars with a pure nucleonic-leptonic
equation of state.

</DOC>
<DOC>
<DOCNO> 150552 </DOCNO>
Geometry of The Embedding of Supergravity Scalar Manifolds in D=11 and


  Several recent papers have made considerable progress in proving the
existence of remarkable consistent Kaluza-Klein sphere reductions of D=10 and
D=11 supergravities, to give gauged supergravities in lower dimensions. A proof
of the consistency of the full gauged SO(8) reduction on S^7 from D=11 was
given many years ago, but from a practical viewpoint a reduction to a smaller
subset of the fields can be more manageable, for the purposes of lifting
lower-dimensional solutions back to the higher dimension. The major complexity
of the spherical reduction Ansatze comes from the spin-0 fields, and of these,
it is the pseudoscalars that are the most difficult to handle. In this paper we
address this problem in two cases. One arises in a truncation of SO(8) gauged
supergravity in four dimensions to U(1)^4, where there are three pairs of
dilatons and axions in the scalar sector. The other example involves the
truncation of SO(6) gauged supergravity in D=5 to a subsector containing a
scalar and a pseudoscalar field, with a potential that admits a second
supersymmetric vacuum aside from the maximally-supersymmetric one. We briefly
discuss the use of these emdedding Ansatze for the lifting of solutions back to
the higher dimension.

</DOC>
<DOC>
<DOCNO> 11092 </DOCNO>
Ising films with surface defects


  The influence of surface defects on the critical properties of magnetic films
is studied for Ising models with nearest-neighbour ferromagnetic couplings. The
defects include one or two adjacent lines of additional atoms and a step on the
surface. For the calculations, both density-matrix renormalization group and
Monte Carlo techniques are used. By changing the local couplings at the defects
and the film thickness, non-universal features as well as interesting crossover
phenomena in the magnetic exponents are observed.

</DOC>
<DOC>
<DOCNO> 178717 </DOCNO>
Partial Dynamical Symmetries in Nuclei


  Partial dynamical symmetries (PDS) are shown to be relevant to the
interpretation of the $K=0_2$ band and to the occurrence of F-spin multiplets
of ground and scissors bands in deformed nuclei. Hamiltonians with bosonic and
fermionic PDS are presented.

</DOC>
<DOC>
<DOCNO> 117211 </DOCNO>
Maximally Informative Statistics


  In this paper we propose a Bayesian, information theoretic approach to
dimensionality reduction. The approach is formulated as a variational principle
on mutual information, and seamlessly addresses the notions of sufficiency,
relevance, and representation. Maximally informative statistics are shown to
minimize a Kullback-Leibler distance between posterior distributions.
Illustrating the approach, we derive the maximally informative one dimensional
statistic for a random sample from the Cauchy distribution.

</DOC>
<DOC>
<DOCNO> 178415 </DOCNO>
Electroproduction of the d* dibaryon


  The unpolarized cross section for the electroproduction of the isoscalar
$J^\pi = 3^+$ di-delta dibaryon $d^*$ is calculated for deuteron target using a
simple picture of elastic electron-baryon scattering from the $\Delta \Delta
(^7D_1)$ and the $NN (^3S_1)$ components of the deuteron. The calculated
differential cross section at the electron lab energy of 1 GeV has the value of
about 0.24 (0.05) nb/sr at the lab angle of 10$^\circ$ (30$^\circ$) for the
Bonn B potential when the dibaryon mass is taken to be 2.1 GeV. The cross
section decreases rapidly with increasing dibaryon mass. A large calculated
width of 40 MeV for $d^*(\Delta\Delta ^7S_3)$ combined with a small
experimental upper bound of 0.08 MeV for the $d^*$ decay width appears to have
excluded any low-mass $d^*$ model containing a significant admixture of the
$\Delta\Delta (^7S_3)$ configuration.

</DOC>
<DOC>
<DOCNO> 100469 </DOCNO>
Some Remarks Concerning the Feynman "Integral over All Paths" Method


  Suppose we have two nonequivalent but s-equivalent Lagrange functions, the
question arises: are they both equally well fitted for the Feynman quantization
procedure or do they lead to two different quantization schemes.

</DOC>
<DOC>
<DOCNO> 178900 </DOCNO>
Nucleon-deuteron elastic scattering as a tool to probe properties of


  Faddeev equations for elastic Nd scattering have been solved using modern NN
forces combined with the Tucson-Melbourne two-pion exchange three-nucleon
force, with a modification thereof closer to chiral symmetry and the Urbana IX
three-nucleon force. Theoretical predictions for the differential cross section
and several spin observables using NN forces only and NN forces combined with
three-nucleon force models are compared to each other and to the existing data.
A wide range of energies from 3 to 200 MeV is covered. Especially at the higher
energies striking three-nucleon force effects are found, some of which are
supported by the still rare set of data, some are in conflict with data and
thus very likely point to defects in those three-nucleon force models.

</DOC>
<DOC>
<DOCNO> 100281 </DOCNO>
A continuum of totally incomparable hereditarily indecomposable Banach


  A family is constructed of cardinality equal to the continuum, whose members
are totally incomparable, reflexive, hereditarily indecomposable Banach spaces.

</DOC>
<DOC>
<DOCNO> 39786 </DOCNO>
Exclusion Limits on the WIMP-Nucleon Cross-Section from the Cryogenic


  The Cryogenic Dark Matter Search (CDMS) employs Ge and Si detectors to search
for WIMPs via their elastic-scattering interactions with nuclei while
discriminating against interactions of background particles. CDMS data give
limits on the spin-independent WIMP-nucleon elastic-scattering cross-section
that exclude unexplored parameter space above 10 GeV c^{-2} WIMP mass and, at >
84% CL, the entire 3$\sigma$ allowed region for the WIMP signal reported by the
DAMA experiment.

</DOC>
<DOC>
<DOCNO> 122247 </DOCNO>
Cosmological Origin of the Lowest Metallicity Halo Stars


  We explore the predictions of the standard hierarchical clustering scenario
of galaxy formation, regarding the numbers and metallicities of PopIII stars
likely to be found within our Galaxy today. By PopIII we shall be referring to
stars formed at large redshift ($z>4$), with low metallicities
($[Z/Z_{\odot}]<-2.5$) and in small systems (total mass $\simlt$ $2\times
10^{8} M_{\odot}$) that are extremely sensitive to stellar feedback, and which
through a prescribed merging history (Lacey & Cole 1993) end up becoming part
of the Milky Way today. An analytic, extended Press-Schechter formalism is used
to get the mass functions of halos which will host PopIII stars at a given
redshift, and which will end up in Milky Way sized systems today. Each of these
is modeled as a mini galaxy, with a detailed treatment of the dark halo
structure, angular momentum distribution, final gas temperature and disk
instabilities, all of which determine the fraction of the baryons which are
subject to star formation. Use of new primordial metallicity stellar
evolutionary models allows us to trace the history of the stars formed, give
accurate estimates of their expected numbers today, and their location in
$L/L_{\odot}$ vs. $T/K$ HR diagrams. A first comparison with observational data
suggests that the IMF of the first stars was increasingly high mass weighted
towards high redshifts, levelling off at $z\simgt 9$ at a characteristic
stellar mass scale $m_s=10-15 M_\odot$.

</DOC>
<DOC>
<DOCNO> 7690 </DOCNO>
Spin twists, domain walls, and the cluster spin-glass phase of weakly


  We examine the role of spin twists in the formation of domain walls, often
called stripes, by focusing on the spin textures found in the cluster spin
glass phases of LaSrCuO and YCaBaCuO. To this end, we derive an analytic
expression for the spin distortions produced by a frustrating bond, both near
the core region of the bond and in the far field, and then derive an expression
for interaction energies between such bonds. We critique our analytical theory
by comparison to numerical solutions of this problem and find excellent
agreement. By looking at collections of small numbers of such bonds localized
in some region of a lattice, we demonstrate the stability of small ``clusters''
of spins, each cluster having its own orientation of its antiferromagnetic
order parameter. Then, we display a domain wall corresponding to spin twists
between clusters of locally ordered spins showing how spin twists can serve as
a mechanism for stripe formation. Since the charges are localized in this
model, we emphasize that these domain walls are produced in a situation for
which no kinetic energy is present in the problem.

</DOC>
<DOC>
<DOCNO> 80629 </DOCNO>
Existence of Algebraic Decay in Nonabelian Ferromagnets


  The low temperature regime of nonabelian two-dimensional ferromagnets is
investigated. The method involves mapping such models into certain site-bond
peroclation processes and using ergodicity in a novel fashion. It is concluded
that all ferromagnets possessing a continuous symmetry (abelian or not)
exihibit algebraic decay of correlations at sufficiently low temperatures.

</DOC>
<DOC>
<DOCNO> 39668 </DOCNO>
Standard and exotic interpretations of the atmospheric neutrino data


  The present status of some theoretical interpretations of the atmospheric
neutrino deficit is briefly discussed. Specifically, we show the results for
the FC mechanism and for the standard oscillation hypothesis, both in the
active and in the sterile channels. All these mechanisms are able to fit the
present data to a good statistical level. Among them, the nu_mu --> nu_tau
oscillation is certainly the best explanation to the atmospheric neutrino
deficit, providing a remarkably good agreement with the data.

</DOC>
<DOC>
<DOCNO> 121153 </DOCNO>
Numerical hydrodynamics: SPH vs. AMR


  The advantages and disadvantages of two approaches to astrophysical
hydrodynamics, Smoothed Particle Hydrodynamics and Adaptive Mesh Refinement,
are briefly discussed together with some current problems of computational
hydrodynamics.

</DOC>
<DOC>
<DOCNO> 39667 </DOCNO>
A Comparison of Spin Observable Predictions for RHIC


  There have been many versions of spin-dependent parton distributions in the
literature. Although most agree with present data within uncertainties, they
are based upon different physical assumptions. Some physical models are
discussed and the corresponding predictions for double spin asymmetries are
shown. A summary of the most feasible measurements in the appropriate kinematic
regions at RHIC, which should yield the most useful information about the
polarized gluon distribution, is given.

</DOC>
<DOC>
<DOCNO> 12005 </DOCNO>
Renormalization Group and Probability Theory


  The renormalization group has played an important role in the physics of the
second half of the twentieth century both as a conceptual and a calculational
tool. In particular it provided the key ideas for the construction of a
qualitative and quantitative theory of the critical point in phase transitions
and started a new era in statistical mechanics. Probability theory lies at the
foundation of this branch of physics and the renormalization group has an
interesting probabilistic interpretation as it was recognized in the middle
seventies. This paper intends to provide a concise introduction to this aspect
of the theory of phase transitions which clarifies the deep statistical
significance of critical universality.

</DOC>
<DOC>
<DOCNO> 85128 </DOCNO>
Back Reaction Problem in the Inflationary Universe


  We investigate the back reaction of cosmological perturbations on an
inflationary universe using the renormalization-group method. The second-order
zero mode solution which appears by the nonlinearity of the Einstein equation
is regarded as a secular term of a perturbative expansion, we renormalized a
constant of integration contained in the background solution and absorbed the
secular term to this constant in a gauge-invariant manner. The resultant
renormalization-group equation describes the back reaction effect of
inhomogeneity on the background universe. For scalar type classical
perturbation, by solving the renormalization-group equation, we find that the
back reaction of the long wavelength fluctuation works as a positive spatial
curvature, and the short wavelength fluctuation works as a radiation fluid. For
the long wavelength quantum fluctuation, the effect of back reaction is
equivalent to a negative spatial curvature.

</DOC>
<DOC>
<DOCNO> 11497 </DOCNO>
Confinement symmetry, mobility anisotropy, and metallic behavior in


  We study two dimensional hole systems confined to GaAs quantum wells grown on
the (311)A surface of GaAs substrates. Such samples exhibit an in-plane
mobility anisotropy. At constant 2D hole density, we vary the symmetry of the
quantum well potential and measure the temperature dependence of the
resistivity along two different current directions, in a regime where the
samples exhibit metallic behavior. The symmetry has a significant and
non-trivial effect on the metallic behavior. Moreover, differences between the
temperature-dependence of the resistivity along the two mobility directions
point to specific scattering mechanisms being important in the expression of
the metallic behavior.

</DOC>
<DOC>
<DOCNO> 102144 </DOCNO>
Versal deformations and superpotentials for rational curves in smooth


  The versal deformation space of a smooth rational curve in a smooth complex
threefold is explicitly computed under certain hypotheses. Under an additional
hypothesis, the versal deformation space is then shown to be the variety of
critical points of a holomorphic function, the superpotential, as predicted by
the consideration of D-branes in string theory.

</DOC>
<DOC>
<DOCNO> 122191 </DOCNO>
Hipparcos Luminosities and Asteroseismology


  Asteroseismology involves using the resonant frequencies of a star to infer
details about its internal structure and evolutionary state. Oscillation
frequencies are most useful when accompanied by accurate measurements of the
more traditional stellar parameters such as luminosity and effective
temperature. The Hipparcos catalogue provides luminosities with precisions of a
few percent or better for many oscillating stars. I briefly discuss the
importance of Hipparcos measurements for interpreting asteroseismic data on
three types of oscillating stars: delta Scuti variables, rapidly oscillating Ap
stars and solar-like stars. I also retract the endorsement I made during my
talk of Trimble's (1995) suggestion to change the spelling of
"asteroseismology".

</DOC>
<DOC>
<DOCNO> 12706 </DOCNO>
Microscopic Models of 2D Magnets with Fractionalized Excitations


  We demonstrate that spin-charge separation can occur in two dimensions and
note its confluence with superconductivity, topology, gauge theory, and
fault-tolerant quantum computation. We construct a microscopic Ising-like model
and, at a special coupling constant value, find its exact ground state as well
as neutral spin 1/2 (spinon), spinless charge e (holon), and $Z_2$ vortex
(vison) states and energies. The fractionalized excitations reflect the
topological order of the ground state which is evinced by its fourfold
degeneracy on the torus -- a degeneracy which is unrelated to translational or
rotational symmetry -- and is described by a $Z_2$ gauge theory. Our model is
related to the quantum dimer model and is a member of a family of
topologically-ordered models, one of which is integrable and realizes the toric
quantum error correction code.

</DOC>
<DOC>
<DOCNO> 80885 </DOCNO>
Non-perturbative scaling tests of twisted mass QCD


  We present a scaling study of lattice QCD with O(a) improved Wilson fermions
and a chirally twisted mass term. In order to get precise results with a
moderate computational effort, we have considered a system of physical size of
0.75^3 * 1.5 fm^4 with Schroedinger functional boundary conditions in the
quenched approximation. Looking at meson observables in the pseudoscalar and
vector channels, we find that O(a) improvement is effective and residual cutoff
effects are fairly small.

</DOC>
<DOC>
<DOCNO> 84804 </DOCNO>
Post-Newtonian SPH calculations of binary neutron star coalescence. II.


  Using our new Post-Newtonian SPH (smoothed particle hydrodynamics) code, we
study the final coalescence and merging of neutron star (NS) binaries. We vary
the stiffness of the equation of state (EOS) as well as the initial binary mass
ratio and stellar spins. Results are compared to those of Newtonian
calculations, with and without the inclusion of the gravitational radiation
reaction. We find a much steeper decrease in the gravity wave peak strain and
luminosity with decreasing mass ratio than would be predicted by simple
point-mass formulae. For NS with softer EOS (which we model as simple
$\Gamma=2$ polytropes) we find a stronger gravity wave emission, with a
different morphology than for stiffer EOS (modeled as $\Gamma=3$ polytropes as
in our previous work). We also calculate the coalescence of NS binaries with an
irrotational initial condition, and find that the gravity wave signal is
relatively suppressed compared to the synchronized case, but shows a very
significant second peak of emission. Mass shedding is also greatly reduced, and
occurs via a different mechanism than in the synchronized case. We discuss the
implications of our results for gravity wave astronomy with laser
interferometers such as LIGO, and for theoretical models of gamma-ray bursts
(GRBs) based on NS mergers.

</DOC>
<DOC>
<DOCNO> 8257 </DOCNO>
High-field AFMR in single-crystalline La_{0.95}Sr_{0.05}MnO_3:


  High-field antiferromagnetic-resonance (AFMR) spectra were obtained in the
frequency range 60 GHz < \nu < 700 GHz and for magnetic fields up to 8 T in
twin-free single crystals of La_{0.95}Sr_{0.05}MnO_3. At low temperatures two
antiferromagnetic modes were detected, which reveal different excitation
conditions and magnetic field dependencies. No splitting of these modes was
observed for any orientation of the static magnetic field excluding the
phase-separation scenario for this composition. Instead, the full data set
including the anisotropic magnetization can be well described using a
two-sublattice model of a canted antiferromagnetic structure.

</DOC>
<DOC>
<DOCNO> 152598 </DOCNO>
Field spectrum and degrees of freedom in AdS/CFT correspondence and


  Compactified AdS space can not be mapped into just one Poincare coordinate
chart. This implies that the bulk field spectrum is discrete despite the
infinite range of the coordinates. We discuss here why this discretization of
the field spectrum seems to be a necessary ingredient for the holographic
mapping. For the Randall Sundrum model we show that this discretization appears
even without the second brane.

</DOC>
<DOC>
<DOCNO> 122055 </DOCNO>
BeppoSAX observations of Narrow-Line Seyfert 1 galaxies: II. Ionized


  The BeppoSAX observations of the bright Narrow-Line Seyfert 1 galaxy Ark 564
are presented along with a high quality optical spectrum taken at the 1.5m
telescope at La Silla. The 0.1-10 keV X-ray spectrum is characterized by a
strong soft component which is best described by blackbody-like emission with a
temperature of about 160 eV. At higher energies a steep (Gamma = 2.4) power-law
tail is present. There is evidence of an ionized reflector in the form of an
iron line and edge. We do not find significant evidence of soft X-ray features
if the spectrum is modelled with a two component continuum. The optical and
X-ray spectral properties support the hypothesis of a high accretion rate onto
a low mass black hole.

</DOC>
<DOC>
<DOCNO> 118544 </DOCNO>
First Detection of Molecular Gas in the Shells of CenA


  Shells are faint arc-like stellar structures, which have been observed around
early type galaxies and are thought to be the result of an interaction. HI gas
has recently been detected in shells, a surprising result in view of the
theoretical predictions that most of the gas should decouple from stars and
fall into the nucleus in such interactions. Here we report the first detection
of molecular gas (CO) in shells, found 15kpc away from the center of NGC5128
(CenA), a giant elliptical galaxy that harbors an active nucleus (AGN). The
ratio between CO and HI emission in the shells is the same as that found in the
central regions, which is unexpected given the metallicity gradient usually
observed in galaxies. We propose that the dynamics of the gas can be understood
within the standard picture of shell formation if one takes into account that
the interstellar medium is clumpy and hence not highly dissipative. The
observed metal enrichment could be due to star formation induced by the AGN jet
in the shells. Furthermore our observations provide evidence that molecular gas
in mergers may be spread out far from the nuclear regions.

</DOC>
<DOC>
<DOCNO> 68196 </DOCNO>
A Model Independent Determination of |V_{ub}|


  It is shown that measuring the lepton invariant mass spectrum in inclusive
semileptonic B -> X_u l nu decay yields a model independent determination of
|V_{ub}|. Unlike the lepton energy and hadronic invariant mass spectra,
nonperturbative effects are only important in the resonance region, and play a
parametrically suppressed role when d\Gamma/dq^2 is integrated over q^2 >
(m_B-m_D)^2, which is required to eliminate the charm background. Perturbative
and nonperturbative corrections are presented to order \alpha_s^2\beta_0 and
\Lambda_{QCD}^2/m_b^2, and the \Lambda_{QCD}^3/m_b^3 corrections are used to
estimate the uncertainty in our results. The utility of the B -> X_s l^+ l^-
decay rate above the \psi(2S) resonance is discussed.

</DOC>
<DOC>
<DOCNO> 99731 </DOCNO>
Stability and BPS branes


  We define the concept of Pi-stability, a generalization of mu-stability of
vector bundles, and argue that it characterizes N=1 supersymmetric brane
configurations and BPS states in very general string theory compactifications
with N=2 supersymmetry in four dimensions.

</DOC>
<DOC>
<DOCNO> 122666 </DOCNO>
Application of the synchrotron proton blazar model to BL Lac objects


  We apply the synchrotron proton blazar (SPB) model to the April 1997 flare of
Markarian 501 and find we are able to fit the observed spectral energy
distribution. We explore the effect of target photon density on the high energy
part of the spectral energy distribution (SED) for fixed assumed magnetic
field, emission region size and Doppler factor and find that the luminosity and
peak frequency of the high energy part of the SED may depend on the luminosity
of the low energy part of the SED in high-frequency peaked BL Lac objects
(HBL).

</DOC>
<DOC>
<DOCNO> 170203 </DOCNO>
Photon antibunching in the fluorescence of individual color centers in


  We have observed photon antibunching in the fluorescence light emitted from a
single N-V center in diamond at room temperature. The possibility of generating
triggerable single photons with such a solide state system is discussed

</DOC>
<DOC>
<DOCNO> 120662 </DOCNO>
Hierarchical galaxy formation and substructure in the Galaxy's stellar


  We develop an explicit model for the formation of the stellar halo from
tidally disrupted, accreted dwarf satellites in the cold dark matter (CDM)
framework, focusing on predictions testable with the Sloan Digital Sky Survey
(SDSS) and other wide-field surveys. Subhalo accretion and orbital evolution
are calculated using a semi-analytic approach within the Press-Schechter
formalism. Motivated by our previous work, we assume that low-mass subhalos (v
< 30 km/s) can form significant populations of stars only if they accreted a
substantial fraction of their mass before the epoch of reionization. With this
assumption, the model reproduces the observed velocity function of galactic
satellites in the Local Group, solving the ``dwarf satellite problem'' without
modifying the popular LCDM cosmology. The disrupted satellites yield a stellar
distribution with a total mass and radial density profile consistent with those
observed for the Milky Way stellar halo. Most significantly, the model predicts
the presence of many large-scale, coherent substructures in the outer halo.
These substructures are remnants of individual, tidally disrupted dwarf
satellite galaxies. Substructure is more pronounced at large galactocentric
radii because of the smaller number density of tidal streams and the longer
orbital times. This model provides a natural explanation for the coherent
structures in the outer stellar halo found in the SDSS commissioning data, and
it predicts that many more such structures should be found as the survey covers
more of the sky. The detection (or non-detection) and characterization of such
structures could eventually test variants of the CDM scenario, especially those
that aim to solve the dwarf satellite problem by enhancing satellite
disruption.

</DOC>
<DOC>
<DOCNO> 99350 </DOCNO>
Superbridge index of composite knots


  An upper bound of the superbridge index of the connected sum of two knots is
given in terms of the braid index of the summands. Using this upper bound and
minimal polygonal presentations, we give an upper bound in terms of the
superbridge index and the bridge index of the summands when they are torus
knots. In contrast to the fact that the difference between the sum of bridge
indices of two knots and the bridge index of their connected sum is always one,
the corresponding difference for the superbridge index can be arbitrarily
large.

</DOC>
<DOC>
<DOCNO> 85037 </DOCNO>
Relativistic phase shifts for Dirac particles interacting with weak


  We present a second-quantized field theory of massive spin one-half particles
or antiparticles in the presence of a weak gravitational field treated as a
spin two external field in a flat Minkowski background. We solve the
difficulties which arise from the derivative coupling and we are able to
introduce an interaction picture. We derive expressions for the scattering
amplitude and for the outgoing spinor to first-order. In several appendices,
the link with the canonical approach in General Relativity is established and a
generalized stationary phase method is used to calculate the outgoing spinor.
We show how our expressions can be used to calculate and discuss phase shifts
in the context of matter-wave interferometry (especially atom or antiatom
interferometry). In this way, many effects are introduced in a unified
relativistic framework, including spin-gravitation terms: gravitational red
shift, Thomas precession, Sagnac effect, spin-rotation effect, orbital and spin
Lense-Thirring effects, de Sitter geodetic precession and finally the effect of
gravitational waves. A new analogy with the electromagnetic interaction is
pointed out.

</DOC>
<DOC>
<DOCNO> 13516 </DOCNO>
Stochastic Dynamics of a Vortex Loop. Large Scale Stirring Force


  Stochastic dynamics of a vortex filament obeying local induced approximation
equation plus random agitation is investigated by analytical and numerical
methods. The character of a stirring force is supposed to be a white noise with
spatial correlator concentrated at large distances comparable with size of the
loop. Dependence of the spectral function $<\mathbf{s}_\kappa ^\alpha
\mathbf{s}_\kappa ^\beta >$ of the vortex line on both the one-dimensional wave
vector $\kappa$ and intensity of the external force correlator
$<\mathbf{\zeta}_\kappa ^\alpha \mathbf{\zeta}_\kappa ^\alpha>$ was studied.
Here $\mathbf{s}_\kappa ^\alpha$ is the Fourier transform of the line element
position $\mathbf{s}^\alpha (\xi, t)$. It is shown that under the influence of
an external random force a vortex ring becomes a small tangle whose mean size
depends on external force intensity. The theoretical predictions and the
numerical results are in reasonable agreement.

</DOC>
<DOC>
<DOCNO> 70124 </DOCNO>
Theoretical Issues in the Tevatron Era


  The Fermilab Tevatron's operation for fixed-target physics from its start in
1983 until the end of fixed-target running in 2000 was marked by extraordinary
peoductivity and variety. Some of the changing theoretal issues associated with
this program are reviewed.

</DOC>
<DOC>
<DOCNO> 118251 </DOCNO>
The large scale distribution of warm ionized gas around nearby radio


  Deep, narrow-band Halpha observations taken with the TAURUS Tunable Filter
(TTF) on the 4.2m WHT telescope are presented for two nearby radio galaxies
with strong jet-cloud interactions. Although the brightest emission line
components are closely aligned with the radio jets --- providing nearby
examples of the ``alignment effect'' most commonly observed in high redshift (z
> 0.5) radio galaxies --- lower surface brightness emission line structures are
detected at large distances (10's of kpc) from the radio jet axis. These latter
structures cannot be reconciled with anisotropic illumination of the ISM by
obscured quasar-like sources, since parts of the structures lay outside any
plausible quasar ionization cones. Rather, the distribution of the emission
lines around the fringes of the extended radio lobes suggests that the gas is
ionized either by direct interaction with the radio components, or by the
diffuse photoionizing radiation fields produced in the shocks generated in such
interactions. These observations serve to emphasise that the ionizing effects
of the radio components can extend far from the radio jet axes, and that deep
emission line imaging observations are required to reveal the true distribution
of warm gas in the host galaxies. We expect future deep imaging observations to
reveal similar structures perpendicular to the radio axes in the high-z radio
galaxies.

</DOC>
<DOC>
<DOCNO> 68469 </DOCNO>
Top-Quark Production and Decay in the MSSM


  We review the features of top-quark decays and loop-induced effects in the
production cross section and CP-violating observables of e+e- -> t t-bar which
are specific to the R-parity conserving Minimal Supersymmetric Standard Model
(MSSM).

</DOC>
<DOC>
<DOCNO> 152262 </DOCNO>
Geometrical aspects of superbrane dynamics


  The geometrical (superembedding) approach is used as a tool for deriving from
the worldvolume dynamics of superbranes field theoretical models exhibiting
partial supersymmetry breaking. In this way we obtain nonlinear actions for
Goldstone superfields associated with physical degrees of freedom of the
superbranes.

</DOC>
<DOC>
<DOCNO> 102176 </DOCNO>
D-branes, Exceptional Sheaves and Quivers on Calabi-Yau manifolds: From


  We present a method based on mutations of helices which leads to the
construction (in the large volume limit) of exceptional coherent sheaves
associated with the $(\sum_al_a=0)$ orbits in Gepner models. This is explicitly
verified for a few examples including some cases where the ambient weighted
projective space has singularities not inherited by the Calabi-Yau
hypersurface. The method is based on two conjectures which lead to the
analog,in the general case, of the Beilinson quiver for $\BP^n$. We discuss how
one recovers the McKay quiver using the gauged linear sigma model (GLSM) near
the orbifold or Gepner point in K\"ahler moduli space.

</DOC>
<DOC>
<DOCNO> 117548 </DOCNO>
A search for precursors of Ultracompact HII Regions in a sample of


  The James Clerk Maxwell Telescope has been used to obtain submillimeter and
millimeter continuum photometry of a sample of 30 IRAS sources previously
studied in molecular lines and centimeter radio continuum. All the sources have
IRAS colours typical of very young stellar objects (YSOs) and are associated
with dense gas. In spite of their high luminosities (L>10000 solar units), only
ten of these sources are also associated with a radio counterpart. In 17 cases
we could identify a clear peak of millimeter emission associated with the IRAS
source, while in 9 sources the millimeter emission was extended or faint and a
clear peak could not be identified; upper limits were found in 4 cases only.
  Using simple greybody fitting model to the observed SED, we derive global
properties of the circumstellar dust. The dust temperature varies from 24 K to
45 K, while the exponent of the dust emissivity vs frequency power-law spans a
range 1.56<beta<2.38, characteristic of silicate dust; total circumstellar
masses range up to more than 500 solar masses.
  We find that for sources with comparable luminosities, the total column
densities derived from the dust masses do not distinguish between sources with
and without radio counterpart. We interpret this result as an indication that
dust does not play a dominant role in inhibiting the formation of the HII
region. We examine several scenarios for their origin in terms of newborn ZAMS
stars and although most of these fail to explain the observations, we cannot
exclude that these sources are young stars already on the ZAMS with modest
residual accretion that quenches the expansion of the HII region. Finally, we
consider the possibility that the IRAS sources are high-mass pre-ZAMS (or
pre-H-burning) objects deriving most of the emitted luminosity from accretion.

</DOC>
<DOC>
<DOCNO> 7961 </DOCNO>
Lattice computation of energy moments in canonical and Gaussian quantum


  We derive a lattice approximation for a class of equilibrium quantum
statistics describing the behaviour of any combination and number of bosonic
and fermionic particles with any sufficiently binding potential. We then
develop an intuitive Monte Carlo algorithm which can be used for the
computation of expectation values in canonical and Gaussian ensembles and give
lattice observables which will converge to the energy moments in the continuum
limit. The focus of the discussion is two-fold: in the rigorous treatment of
the continuum limit and in the physical meaning of the lattice approximation.
In particular, it is shown how the concepts and intuition of classical physics
can be applied in this sort of computation of quantum effects. We illustrate
the use of the Monte Carlo methods by computing canonical energy moments and
the Gaussian density of states for charged particles in a quadratic potential.

</DOC>
<DOC>
<DOCNO> 72153 </DOCNO>
Investigation of meson loop effects in the Nambu-Jona-Lasinio model


  The influence of mesonic fluctuations on quantities in the Nambu-Jona-Lasinio
model is examined in different approximation schemes: an expansion in powers of
1/N_c and an expansion up to one-meson loop in the effective action formalism.
It is explicitely proved that the Goldstone theorem as well as the
Gell-Mann-Oakes-Renner relation hold within those schemes. The influence of
meson-loop effects on the quark condensate, the pion mass, the pion decay
constant and properties of rho- and sigma-meson are investigated. First we
focus on the determination of a consistent set of parameters. In the 1/N_c
expansion scheme it is possible to find a set of parameters which allows to
simultaneously describe the quantities in the pion sector and those related to
the rho-meson, whereas this turns out to be not possible within the expansion
of the effective action. Besides, the relation of our model to hadronic models
is discussed. In the last part of this thesis the behavior of the quark
condensate at nonzero temperature is studied. In the low-temperature region
agreement with the model independent chiral perturbation theory result in
lowest order can be obtained. The perturbative 1/N_c expansion scheme does not
allow for an examination of the chiral phase transition at higher temperatures,
whereas this is possible within the meson-loop approximation scheme. A first
order phase transition is found.

</DOC>
<DOC>
<DOCNO> 9725 </DOCNO>
Quantum Impurity in a Nearly Critical Two Dimensional Antiferromagnet


  We describe the spin dynamics of an arbitrary localized impurity in an
insulating two dimensional antiferromagnet, across the host transition from a
paramagnet with a spin gap to a Neel state. The impurity spin susceptibility
has a Curie-like divergence at the quantum-critical coupling, but with a
universal, effective spin which is neither an integer nor a half-odd-integer.
In the Neel state, the transverse impurity susceptibility is a universal number
divided by the host spin stiffness (which determines the energy cost to slow
twists in the orientation of the Neel order). These, and numerous other results
for the thermodynamics, Knight shift, and magnon damping have significant
applications to experiments on layered transition metal oxides.

</DOC>
<DOC>
<DOCNO> 68751 </DOCNO>
Quark induced excitations of the instanton liquid


  The selfconsistent approach to the quark interactions in the instanton liquid
is developed within the tadpole approximation calculating the basic functional
integral. The effective Lagrangian obtained includes colourless scalar field
interacting with quarks. The origin of this dynamical field as an interaction
carrier in soft momentum region is discussed.

</DOC>
<DOC>
<DOCNO> 100443 </DOCNO>
Cohomology of the infinite-order jet space


  De Rham cohomology, $d_V$- and $d_H$-cohomology of the differential algebra
of locally pull-back exterior forms on the infinite-order jet manifold of a
smooth fibre bundle are calculated.

</DOC>
<DOC>
<DOCNO> 7653 </DOCNO>
Lyapunov exponent for pure and random Fibonacci chains


  We study the Lyapunov exponent for electron and phonon excitations, in pure
and random Fibonacci quasicrystal chains, using an exact real space
renormalization group method, which allows the calculation of the Lyapunov
exponent as a function of the energy. It is shown that the Lyapunov exponent on
a pure Fibonacci chain has a self-similar structure, characterized by a scaling
index that is independent of the energy for the electron excitations,
''diagonal'' or ''off-diagonal'' quasiperiodic, but is a function of the energy
for the phonon excitations. This scaling behavior implies the vanishing of the
Lyapunov exponent for the states on the spectrum, and hence the absence of
localization on the Fibonacci chain, for the various excitations considered. It
is also shown that disordered Fibonacci chains, with random tiling that
introduces phason flips at certain sites on the chain, exhibit the same
Lyapunov exponent as the pure Fibonacci chain, and hence this type of disorder
is irrelevant, either in the case of electron or phonon excitations.

</DOC>
<DOC>
<DOCNO> 12679 </DOCNO>
Water-Like Anomalies for Core-Softened Models of Fluids: Two-Dimensional


  We use molecular dynamics simulations in two dimensions to investigate the
possibility that a core-softened potential can reproduce static and dynamic
anomalies found experimentally in liquid water: (i) the increase in specific
volume upon cooling, (ii) the increase in isothermal compressibility upon
cooling, and (iii) the increase in the diffusion coefficient with pressure. We
relate these anomalies to the shape of the potential. We obtain the phase
diagram of the system and identify two solid phases: a square crystal (high
density phase), and a triangular crystal (low density phase). We also discuss
the relation between the anomalies observed and the polymorphism of the solid.
Finally, we compare the phase diagram of our model system with experimental
data, noting especially the line of temperatures of maximum density, line of
pressures of maximum diffusion constant, and line of temperatures of minimum
isothermal compressibility.

</DOC>
<DOC>
<DOCNO> 100343 </DOCNO>
The dual of the James Tree space is asymptotically uniformly convex


  The dual of the James Tree space is asymptotically uniformly convex.

</DOC>
<DOC>
<DOCNO> 101440 </DOCNO>
Some second-order partial differential equations associated with Lie


  In this note we survey results in recent research papers on the use of Lie
groups in the study of partial differential equations. The focus will be on
parabolic equations, and we will show how the problems at hand have solutions
that seem natural in the context of Lie groups. The research is joint with D.W.
Robinson, as well as other researchers who are listed in the references.

</DOC>
<DOC>
<DOCNO> 101296 </DOCNO>
La fonction Zeta de Riemann prend une infinite de valeurs irrationnelles


  We provide a lower bound for the dimension of the vector space spanned by 1
and by the values of the Riemann Zeta function at the first odd integers. As a
consequence, the Zeta function takes infinitely many irrational values at odd
integers.

</DOC>
<DOC>
<DOCNO> 179037 </DOCNO>
Hadrons in dense and hot matter: implications of chiral symmetry


  Recent developments on medium modifications of hadron properties in dense and
hot hadronic matter are discussed. I will focus in particular on the behavior
of spectral functions associated to collective scalar-isoscalar modes, kaons
and vector mesons from ordinary nuclear matter to highly excited matter
produced in relativistic heavy-ion collisions from SIS to SPS energies. Various
theoretical approaches are presented in connection with the interpretation of
experimental data. Special emphasis will be put on the role of chiral dynamics
and chiral symmetry restoration. I will discuss in particular to which extent
the broadening of the rho meson peak signals the onset of chiral symmetry
restoration.

</DOC>
<DOC>
<DOCNO> 150724 </DOCNO>
Invasion of the Giant Gravitons from Anti-de Sitter Space


  It has been known for some time that the AdS/CFT correspondence predicts a
limit on the number of single particle states propagating on the compact
spherical component of the AdS-times-sphere geometry. The limit is called the
stringy exclusion principle. The physical origin of this effect has been
obscure but it is usually thought of as a feature of very small distance
physics. In this paper we will show that the stringy exclusion principle is due
to a surprising large distance phenomenon. The massless single particle states
become progressively less and less point-like as their angular momentum
increases. In fact they blow up into spherical branes of increasing size. The
exclusion principle is simply understood as the condition that the particle
should not be bigger than the sphere that contains it.

</DOC>
<DOC>
<DOCNO> 116277 </DOCNO>
Formation of Patterns in Intense Hadron Beams. The Amplitude Equation


  We study the longitudinal motion of beam particles under the action of a
single resonator wave induced by the beam itself. Based on the method of
multiple scales we derive a system of coupled amplitude equations for the
slowly varying part of the longitudinal distribution function and for the
resonator wave envelope, corresponding to an arbitrary wave number. The
equation governing the slow evolution of the voltage envelope is show to be of
Ginzburg-Landau type.

</DOC>
<DOC>
<DOCNO> 119461 </DOCNO>
Neutrino-pair emission in a strong magnetic field


  We study the neutrino emissivity of strongly magnetized neutron stars due to
the charged and neutral current couplings of neutrinos to baryons in strong
magnetic fields. The leading order neutral current process is the one-body
neutrino-pair bremsstrahlung, which does not have an analogue in the zero field
limit. The leading order charged current reaction is the known generalization
of the direct Urca processes to strong magnetic fields. While for superstrong
magnetic fields in excess of $10^{18}$ G the direct Urca process dominates the
one-body bremsstrahlung, we find that for fields on the order $10^{16}-10^{17}$
G and temperatures a few times $10^9$ K the one-body bremsstrahlung is the
dominant process. Numerical computation of the resulting emissivity, based on a
simple parametrization of the equation of state of the $npe$-matter in a strong
magnetic field, shows that the emissivity of this reaction is of the same order
of magnitude as that of the modified Urca process in the zero field limit.

</DOC>
<DOC>
<DOCNO> 117834 </DOCNO>
X-ray/optical observations of XTE J0421+560/CI Cam in quiescence


  We report on a BeppoSAX observation of the transient X-ray source XTE
J0421+560 during quiescence performed ~150 days after the 1998 April outburst.
The source had an unabsorbed 0.5-10 keV flux of 6.7x10^{-12} erg/cm2/s and was
still remarkably soft with most of the emission below 2 keV. The X-ray spectrum
can be fit with the same two-temperature model as the outburst observations.
There is evidence for the presence of an Iron emission feature at ~7 keV. We
report also on a series of optical observations performed using the 72 cm
Teramo-Normale Telescope (TNT) of the Teramo Observatory, and the 1.5 m Loiano
Telescope of the Bologna Observatory. The optical spectrum includes very strong
Balmer emission lines, He I, [Fe II], and [O I] features. From the observed
L_x/Lopt~10^{-3} the quiescent optical emission cannot be due to re-processing
of the X-rays, but has to be generated in the optical companion or the
circumstellar material. Moreover, the quiescent X-ray luminosity cannot be due
to the optical star if it is of spectral type OB. Although the nature of the
compact object present in the XTE J0421+560/CI Cam system cannot be firmly
established, we speculate that it is most probably a white dwarf.

</DOC>
<DOC>
<DOCNO> 9363 </DOCNO>
Generalized Compressibility in a Glass Forming Liquid


  We introduce a new quantity to probe the glass transition. This quantity is a
linear generalized compressibility which depends solely on the positions of the
particles. We have performed a molecular dynamics simulation on a glass forming
liquid consisting of a two component mixture of soft spheres in three
dimensions. As the temperature is lowered, the generalized compressibility
drops sharply at the glass transition. Our results are consistent with the
kinetic view of the glass transition, but not with an underlying second order
phase transition.

</DOC>
<DOC>
<DOCNO> 13664 </DOCNO>
Cluster Monte Carlo Simulations of the Nematic--Isotropic Transition


  We report the results of simulations of the Lebwohl-Lasher model of the
nematic-isotropic transition using a new cluster Monte Carlo algorithm. The
algorithm is a modification of the Wolff algorithm for spin systems, and
greatly reduces critical slowing down. We calculate the free energy in the
neighborhood of the transition for systems up to linear size 70. We find a
double well structure with a barrier that grows with increasing system size,
obeying finite size scaling for systems of size greater than 35. We thus obtain
an estimate of the value of the transition temperature in the thermodynamic
limit.

</DOC>
<DOC>
<DOCNO> 10340 </DOCNO>
Novel interference effects and a new Quantum phase in mesoscopic systems


  Mesoscopic systems have provided an opportunity to study quantum effects
beyond the atomic realm. In these systems quantum coherence prevails over the
entire sample. We discuss several novel effects related to persistent currents
in open systems which do not have analogues in closed systems. Some phenomena
arising simultaneously due to two non-classical effects namely, Aharonov-Bohm
effect and quantum tunneling are presented. Simple analysis of sharp phase
jumps observed in double-slit Aharonov-Bohm experiments is given. Some
consequences of parity violation are elaborated. Finally, we briefly describe
the dephasing of Aharonov-Bohm oscillations in Aharonov-Bohm ring geometry due
to spin-flip scattering in one of the arms. Several experimental manifestations
of these phenomena and their applications are given.

</DOC>
<DOC>
<DOCNO> 120206 </DOCNO>
The Rotation Curve of the Large Magellanic Cloud and the Implications


  The rotation of the disk of the Large Magellanic Cloud (LMC) is derived from
the radial velocities of 422 carbon stars. New aspects of this analysis include
the propagation of uncertainties in the LMC proper motion with a Monte Carlo,
and a self-consistent modeling of the rotation curve and disk kinematics. The
rotation curve is well fit by a truncated, finite-thickness exponential disk
model with no dark halo. The velocity dispersion in radial bins decreases from
22 to 15 km/s, then increases to 20 km/s at larger radii. Constant-thickness
models in virial equilibrium cannot be reconciled with the data even if the
effects of LMC or Galactic dark halos are included. If the disk is virialized,
the LMC disk is flared. We model the velocity dispersion at large radii (R > 6
kpc) as a maximal flared disk under the influence of the Galactic dark halo,
which favors a mean density for the latter of 0.00025 M_sol/pc^3 at the LMC
distance. LMC stellar kinematics play an important role in elucidating the
nature of MACHOs, a dark population inferred from LMC microlensing. We have
constructed a truncated and flared maximal disk model for the LMC which is
kinematically based. Our model does not include a nonvirialized component such
as tidal debris. Our upper limit on the self-lensing optical depth is in good
agreement with that obtained from less sophisticated models, and is an order of
magnitude too small to account for the MACHO microlensing signal [Abridged].

</DOC>
<DOC>
<DOCNO> 11678 </DOCNO>
Electronic structure, hyperfine interactions and disordering effects in


  Iron nitride Fe4N is studied by full-potential LAPW method. Structure
parameters, electronic and magnetic properties as well as hyperfine interaction
parameters are obtained. We observe perfect agreement with experimental
results. Hypothetical Fe4N structure was also calculated to study the influence
of disordering effects on parameters of Moessbauer spectra. We performed
detailed analysis of EFG formation on Fe nuclei including magnetization
effects. We show that the formation of N-Fe-N local configuration is
energetically favourable in nitrogen austenites.

</DOC>
<DOC>
<DOCNO> 179038 </DOCNO>
Validity of the Impulse Approximation and Quasielastic (e,e'p) Reactions


  We assess the combined effect of ground-state correlations, meson-exchange
and isobar currents upon the cross sections for quasielastic (e,e'p) reactions
from nuclei. Four-momenta in the range 0.1 \leq Q^2 \leq 1 GeV^2 are addressed.
We observe that for $Q^2$ values exceeding 0.2 GeV^2, quasielastic conditions
and missing momenta below the Fermi momentum, the ground-state correlations and
two-body currents do not dramatically alter the $(e,e'p)$ predictions as they
are obtained in the impulse approximation. Moreover, deviations from the
impulse approximation exhibit a rather modest Q^2 dependence.

</DOC>
<DOC>
<DOCNO> 100452 </DOCNO>
Combinatorial Differential Forms


  We extend to a scheme-theoretic context the notion of a combinatorial
differential form, due to A.Kock in the framework of synthetic differential
geometry. We show that group-valued combinatorial forms on a scheme may be
identified, under very general hypotheses, with traditional Lie algebra-valued
differential forms, and that their Lie algebra structure can be recovered from
first principles. Some basic results from differential geometry (Maurer-Cartan
equation, Bianchi identity), as well as a higher analogue, are obtained by
exploiting this identification.

</DOC>
<DOC>
<DOCNO> 151689 </DOCNO>
Gauging the SU(2) Skyrme model


  In this paper the SU(2) Skyrme model will be reformulated as a gauge theory
and the hidden symmetry will be investigated and explored in the energy
spectrum computation. To this end we purpose a new constraint conversion
scheme, based on the symplectic framework with the introduction of Wess-Zumino
(WZ) terms in an unambiguous way. It is a positive feature not present on the
BFFT constraint conversion. The Dirac's procedure for the first-class
constraints is employed to quantize this gauge invariant nonlinear system and
the energy spectrum is computed. The finding out shows the power of the
symplectic gauge-invariant formalism when compared with another constraint
conversion procedures present on the literature.

</DOC>
<DOC>
<DOCNO> 14024 </DOCNO>
Finite temperature hydrodynamic modes of trapped quantum gases


  The hydrodynamic equations of an ideal fluid formed by a dilute quantum gas
in a parabolic trapping potential are studied analytically and numerically. Due
to the appearance of internal modes in the fluid stratified by the trapping
potential, the spectrum of low-lying modes is found to be dense in the
high-temperature limit, with an infinitely degenerate set of zero-frequency
modes. The spectrum for Bose-fluids and Fermi-fluids is obtained and discussed.

</DOC>
<DOC>
<DOCNO> 10067 </DOCNO>
T_c for dilute Bose gases: beyond leading order in 1/N


  Baym, Blaizot, and Zinn-Justin have recently used the large N approximation
to calculate the effect of interactions on the transition temperature of dilute
Bose gases. We extend their calculation to next-to-leading-order in 1/N and
find a relatively small correction of -26% to the leading-order result. This
suggests that the large N approximation works surprisingly well in this
application.

</DOC>
<DOC>
<DOCNO> 150973 </DOCNO>
Fuzzy Spheres in AdS/CFT Correspondence and Holography from


  We show that the existent fuzzy S^2 and S^4 models are natural candidates for
the quantum geometry on the corresponding spheres in AdS/CFT correspondence.
These models fit nicely the data from the dipole mechanism for the stringy
exclusion principle. In the AdS_2 X S^2 case, we show that a wrapped fractional
membrane can be used to count for the large ground state degeneracy. We also
propose a fuzzy AdS_2 model whose fundamental commutation relation may underlie
the UV/IR connection.

</DOC>
<DOC>
<DOCNO> 9017 </DOCNO>
Energetics of Open Systems and Chemical Potential From Micro-Dynamics


  We present the energetic aspect of open systems which may exchange particles
with their environments. Our attention shall be paid to the scale that the
motion of the particles is described by the classical Langevin dynamics. Along
a particular realization of the stochastic process, we study the energy
transfer into the open system from the environments. We are able to clarify how
much energy each particle carries when it enters or leaves the system. On the
other hand, the chemical potential should be considered as the concept in macro
scale, which is relevant to the free energy potential with respect to the
number of particles. Keywords: open systems, stochastic energetics, chemical
potential

</DOC>
<DOC>
<DOCNO> 68252 </DOCNO>
Inflationary models with a flat potential enforced by non-abelian


  Non-abelian discrete gauge symmetries can provide the inflaton with a flat
potential even when one takes into account gravitational strength effects. The
discreteness of the symmetries also provide special field values where
inflation can end via a hybrid type mechanism. An interesting feature of this
method is that it can naturally lead to extremely flat potentials and so, in
principle, to inflation at unusually low energy scales. Two examples of
effective field theories with this mechanism are given, one with a hybrid exit
and one with a mutated hybrid exit. They include an explicit example in which
the single field consistency condition is violated.

</DOC>
<DOC>
<DOCNO> 12693 </DOCNO>
Joule heating generated by spin current through Josephson junctions


  We theoretically study the spin-polarized current flowing through a Josephson
junction (JJ) in a spin injection device. When the spin-polarized current is
injected from a ferromagnet (FM) in a superconductor (SC), the charge current
is carried by the superconducting condensate (Cooper pairs), while the spin-up
and spin-down currents flow in the equal magnitude but in the opposite
direction in SC, because of no quasiparticle charge current in SC. This
indicates that not only the Josephson current but also the spin current flow
across JJ at zero bias voltage, thereby generating Joule heating by the spin
current. The result provides a new method for detecting the spin current by
measuring Joule heating at JJ.

</DOC>
<DOC>
<DOCNO> 11613 </DOCNO>
The definition of quasicrystals


  It is argued that the definition of quasicrystals should not include the
requirement that they possess an axis of symmetry that is forbidden in periodic
crystals. The term "quasicrystal" should simply be regarded as an abbreviation
for "quasiperiodic crystal," possibly with two provisos, as discussed below.
The argument is supported by theoretical as well as experimental examples of
quasicrystals without any forbidden symmetry.

</DOC>
<DOC>
<DOCNO> 80675 </DOCNO>
A generalized Ginsparg-Wilson relation


  We show that, under certain general assumptions, any sensible lattice Dirac
operator satisfies a generalized form of the Ginsparg-Wilson relation (GWR).
Those assumptions, on the other hand, are mostly dictated by large momentum
behaviour considerations. We also show that all the desirable properties often
deduced from the standard GWR hold true of the general case as well; hence one
has, in fact, more freedom to modify the form of the lattice Dirac operator,
without spoiling its nice properties. Our construction, a generalized
Ginsparg-Wilson relation (GGWR), is satisfied by some known proposals for the
lattice Dirac operator. We discuss some of these examples, and also present a
derivation of the GGWR in terms of a renormalization group transformation with
a blocking which is not diagonal in momentum space, but nevertheless commutes
with the Dirac operator.

</DOC>
<DOC>
<DOCNO> 11609 </DOCNO>
Driven diffusive system: A study on large n limit


  We study the generalized $n$ component model of a driven diffusive system
with annealed random drive in the large $n$ limit. This non-equilibrium model
also describes conserved order parameter dynamics of an equilibrium model of
ferromagnets with dipolar interaction. In this limit, at zero temperature a
saddle point approximation becomes exact. The length scale in the direction
transverse to the driving field acquires an additional logarithmic correction
in this limit.

</DOC>
<DOC>
<DOCNO> 178607 </DOCNO>
New Solutions to Covariant Non-equilibrium Dynamics


  New solutions of 3+1D covariant kinetic theory are presented for nuclear
collisions in the energy domain Ecm ~ 200 AGeV. They are obtained using MPC, a
new Monte-Carlo parton transport technique that employs very high parton
subdivision that is necessary to preserve covariance. The transport results are
compared with ideal hydrodynamics solutions. We show that the transport
evolution differs significantly from hydrodynamics. In addition, we compare the
transport freeze-out distributions to those obtained from ideal hydrodynamics
with the Cooper-Frye isotherm freeze-out prescription. The transport freeze-out
four-volume is shown to be sensitive to the reaction rates and deviates from
both time-like and space-like freeze-out 3D hypersurfaces commonly assumed. In
particular, we find that there does not exist a universal freeze-out
temperature. Finally, the transverse momentum distributions are found to
deviate by up to an order of magnitude from (Cooper-Frye frozen) hydrodynamics
for a wide range of possible initial conditions and reaction rates at RHIC
energies.

</DOC>
<DOC>
<DOCNO> 117463 </DOCNO>
Gas Rich Dwarf Spheroidals


  We present evidence that nearly half of the dwarf spheroidal galaxies (dSph
and dSph/dIrr) in the Local Group are associated with large reservoirs of
atomic gas, in some cases larger than the stellar mass. The gas is sometimes
found at large distance (~10 kpc) from the center of a galaxy and is not
necessarily centered on it. Similarly large quantities of ionized gas could be
hidden in these systems as well. The properties of some of the gas reservoirs
are similar to the median properties of the High-Velocity Clouds (HVCs); two of
the HI reservoirs are catalogued HVCs. The association of the HI with the dwarf
spheroidals might thus provide a link between the HVCs and stars. We show that
the HI content of the Local Group dSphs and dIrrs exhibits a sharp decline if
the galaxy is within 250 kpc of either the Milky Way or M31. This can be
explained if both galaxies have a sufficiently massive x-ray emitting halo that
produces ram-pressure stripping if a dwarf ventures too close to either giant
spiral. We also investigate tidal stripping of the dwarf galaxies and find that
although it may play a role, it cannot explain the apparent total absence of
neutral gas in most dSph galaxies at distances less than 250 kpc. For the
derived mean density of the hot gas, n_0 = 2.5e-5 cm^-2, ram-pressure stripping
is found to be more than an order of magnitude more effective in removing the
gas from the dSph galaxies. The hot halo, with an inferred mass of 1e10 solar
masses, may represent a reservoir of ~1000 destroyed dwarf systems, either HVCs
or true dwarf galaxies similar to those we observe now.

</DOC>
<DOC>
<DOCNO> 9870 </DOCNO>
Non-linear conduction in charge-ordered Pr$_{0.63}$ Ca$_{0.37}$


  Non-linear conduction in a single crystal of charge-ordered
Pr$_{0.63}$Ca$_{0.37}$MnO$_{3}$ has been investigated in an applied magnetic
field. In zero field, the non-linear conduction, which starts at T$<$T$_{CO}$
can give rise to a region of negative differential resistance (NDR) which shows
up below the N\'eel temperature. Application of a magnetic field inhibits the
appearance of NDR and makes the non-linear conduction strongly hysteritic on
cycling of the bias current. This is most severe in the temperature range where
the charge ordered state melts in an applied magnetic field. Our experiment
strongly suggests that application of a magnetic field in the CO regime causes
a coexistance two phases.

</DOC>
<DOC>
<DOCNO> 99646 </DOCNO>
Localization Regions of Local Observables


  Exploiting the properties of the Jost-Lehmann-Dyson representation, it is
shown that in 1+2 or more spacetime dimensions, a nonempty smallest
localization region can be associated with each local observable (except for
the c-numbers) in a theory of local observables in the sense of Araki, Haag,
and Kastler. Necessary and sufficient conditions are given that observables
with spacelike separated localization regions commute (locality of the net
alone does not yet imply this).

</DOC>
<DOC>
<DOCNO> 120648 </DOCNO>
X-ray afterglow detection of the short gamma-ray burst 991014


  GRB 991014 is one of the shortest gamma-ray bursts detected so far with the
Wide Field Cameras aboard BeppoSAX, both in gamma-rays and X-rays. The duration
is 9.6 sec in 2-28 keV and 3.2 sec in 40 to 700 keV (as measured between the
times when 5 and 95% of the burst photons have been accumulated). We refine the
InterPlanetary Network annulus of the burst, present the detection of the X-ray
afterglow of GRB 991014 within this refined annulus, and discuss X-ray and
gamma-ray observations of the prompt and afterglow emission. Except for the
briefness of the prompt event, no other unusual aspects were found in the
prompt and afterglow observations as compared to such measurements in previous
gamma-ray bursts.

</DOC>
<DOC>
<DOCNO> 39727 </DOCNO>
Eperimental Results on Radiative Kaon Decays


  This paper reviews the current status of experimental measurements of
radiative kaon decays. Several experiments at BNL, CERN and FNAL have recently
or will soon complete data collection; as a result, several new results are
available.

</DOC>
<DOC>
<DOCNO> 117803 </DOCNO>
Current Issues


  Cosmic explosions are observed in many astrophysical environments. They range
in scale from hydromagnetic instabilities in the terrestrial magnetotail and
solar ``nanoflares'' to cosmological gamma ray bursts, supernovae and the
protracted intervals of nuclear activity that produce the giant quasars and
radio galaxies. There are many parallels in the analyses of the explosion sites
that are highlighted at this workshop, specifically stellar coronae, accretion
disks, supernovae and compact objects. In this introductory talk, some general
issues are discussed and some more specific questions relating to the
individual sites are raised.

</DOC>
<DOC>
<DOCNO> 7796 </DOCNO>
Glass Transition Temperature and Fractal Dimension of Protein Free


  The free-energy landscape of two peptides is evaluated at various
temperatures and an estimate for its fractal dimension at these temperatures
calculated. We show that monitoring this quantity as a function of temperature
allows to determine the glass transition temperature.

</DOC>
<DOC>
<DOCNO> 117881 </DOCNO>
Detection of Multi-TeV Gamma Rays from Markarian 501 during an


  In 1997, the BL Lac Object Mrk 501 entered a very active phase and was the
brightest source in the sky at TeV energies, showing strong and frequent
flaring. Using the data obtained with a high density air shower array that has
been operating successfully at Yangbajing in Tibet since 1996, we searched for
gamma-ray signals from this source during the period from February through
August in 1997. Our observation detected multi-TeV $\gamma$-ray signals at the
3.7-Sigma level during this period. The most rapid increase of the excess
counts was observed between April 7 and June 16 and the statistical
significance of the excess counts in this period was 4.7-Sigma. Among several
observations of flaring TeV gamma-rays from Mrk 501 in 1997, this is the only
observation using a conventional air shower array. We present the energy
spectrum of gamma-rays which will be worthy to compare with those obtained by
imaging atmospheric Cerenkov telescopes.

</DOC>
<DOC>
<DOCNO> 152437 </DOCNO>
The D-Instanton Partition Function


  The D-instanton partition function is a fascinating quantity because in the
presence of N D3-branes, and in a certain decoupling limit, it reduces to the
functional integral of N=4 U(N) supersymmetric gauge theory for multi-instanton
solutions. We study this quantity as a function of non-commutativity in the
D3-brane theory, VEVs corresponding to separating the D3-branes and alpha'.
Explicit calculations are presented in the one-instanton sector with arbitrary
N, and in the large-N limit for all instanton charge. We find that for general
instanton charge, the matrix theory admits a nilpotent fermionic symmetry and
that the action is Q-exact. Consequently the partition function localizes on
the minima of the matrix theory action. This allows us to prove some general
properties of these integrals. In the non-commutative theory, the contributions
come from the ``Higgs Branch'' and are equal to the Gauss-Bonnet-Chern integral
of the resolved instanton moduli space. Separating the D3-branes leads to
additional localizations on products of abelian instanton moduli spaces. In the
commutative theory, there are additional contributions from the ``Coulomb
Branch'' associated to the small instanton singularities of the instanton
moduli space. We also argue that both non-commutativity and alpha'-corrections
play a similar role in suppressing the contributions from these singularities.
Finally we elucidate the relation between the partition function and the Euler
characteristic of the instanton moduli space.

</DOC>
<DOC>
<DOCNO> 151331 </DOCNO>
Elliptic Models, Type IIB Orientifolds and the Ads/CFT Correspondence


  We analyze the large N supergravity descriptions of the class of type IIB
models T-dual to elliptic type IIA brane configurations containing two
orientifold 6-planes and up to two NS 5-branes. The T-dual IIB configurations
contain N D3-branes in the background of an orientifold 7-plane and, in some
models, a Z_2 orbifold and/or D7-branes, which give rise to four-dimensional
N=2 (or N=4) gauge theories with at most two factors. We identify the chiral
primary states of the supergravity theories, and match them to gauge invariant
operators of the corresponding superconformal theories using Maldacena's
duality.

</DOC>
<DOC>
<DOCNO> 10455 </DOCNO>
Free-volume kinetic models of granular matter


  We show that the main dynamical features of granular media can be understood
by means of simple models of fragile-glass forming liquid provided that gravity
alone is taken into account. In such lattice-gas models of cohesionless and
frictionless particles, the compaction and segregation phenomena appear as
purely non-equilibrium effects unrelated to the Boltzmann-Gibbs measure which
in this case is trivial. They provide a natural framework in which slow
relaxation phenomena in granular and glassy systems can be explained in terms
of a common microscopic mechanism given by a free-volume kinetic constraint.

</DOC>
<DOC>
<DOCNO> 13692 </DOCNO>
A model for complex aftershock sequences


  The decay rate of aftershocks is commonly very well described by the modified
Omori law, $n(t) \propto t^{-p}$, where n(t) is the number of aftershocks per
unit time, t is the time after the main shock, and p is a constant in the range
0.9<p<1.5, and usually close to 1. But there are also more complex aftershock
sequences for which the Omori law can be considered only as a first
approximation. One of these complex aftershock sequences took place in the
Eastern Pyrenees on February 18, 1996, and was described in detail by {\it
Correig et al.} [1997]. In this paper, we propose a new model inspired by
dynamic fiber-bundle models to interpret this type of complex aftershock
sequences with sudden increases in the rate of aftershock production not
directly related to the magnitude of the aftershocks (as in the epidemic-type
aftershock sequences). The model is a simple, discrete, stochastic fracture
model where the elements (asperities or barriers) break because of static
fatigue, transfer stress according to a local load-sharing rule and then are
regenerated. We find a very good agreement between the model and the Eastern
Pyrenees aftershock sequence and we propose that the key mechanism for
explaining aftershocks, apart from a time-dependent rock strength, is the
presence of dynamic stress fluctuations which constantly reset the initial
conditions for the next aftershock in the sequence.

</DOC>
<DOC>
<DOCNO> 85642 </DOCNO>
Precanonical Quantization and the Schroedinger Wave Functional


  A relation between the Schroedinger wave functional and the Clifford-valued
wave function which appears in what we call precanonical quantization of fields
and fulfills a Dirac-like generalized covariant Schroedinger equation on the
space of field and space-time variables is discussed. The Schroedinger wave
functional is argued to be the trace of the positive frequency part of the
continual product over all spatial points of the values of the aforementioned
wave function restricted to a Cauchy surface. The standard functional
differential Schroedinger equation is derived as a consequence of the
Dirac-like covariant Schroedinger equation.

</DOC>
<DOC>
<DOCNO> 102099 </DOCNO>
Four short stories about Toeplitz matrix calculations


  The stories told in this paper are dealing with the solution of finite,
infinite, and biinfinite Toeplitz-type systems. A crucial role plays the
off-diagonal decay behavior of Toeplitz matrices and their inverses. Classical
results of Gelfand et al. on commutative Banach algebras yield a general
characterization of this decay behavior. We then derive estimates for the
approximate solution of (bi)infinite Toeplitz systems by the finite section
method, showing that the approximation rate depends only on the decay of the
entries of the Toeplitz matrix and its condition number. Furthermore, we give
error estimates for the solution of doubly infinite convolution systems by
finite circulant systems. Finally, some quantitative results on the
construction of preconditioners via circulant embedding are derived, which
allow to provide a theoretical explanation for numerical observations made by
some researchers in connection with deconvolution problems.

</DOC>
<DOC>
<DOCNO> 8013 </DOCNO>
Anisotropic Fermi surfaces and Kohn-Luttinger superconductivity in two


  The instabilities induced on a two-dimensional system of correlated electrons
by the anisotropies of its Fermi line are analyzed on general grounds. Simple
scaling arguments allow to predict the opening of a superconducting gap with a
well-defined symmetry prescribed by the geometry of the Fermi line. The same
arguments predict a critical dimension of 3/2 for the transition of the
two-dimensional system to non-Fermi liquid behavior. The methods are applied to
the t-t' Hubbard model in a wide range of dopings.

</DOC>
<DOC>
<DOCNO> 69535 </DOCNO>
High-gradient theories as new essential ingredient for the


  Inspiring ourselves by the assumption that the notion of symmetry itself is
insufficient to construct the consistent physics of the Desert (the so-called
region of energies beyond the Standard Model) and some additional insights are
needed, we suggests that high-energy theories must take into account the
higher-order variations of fields. With this in mind we propose the
generalization of the concepts of kinetic energy and free particle. It is shown
that the theory founded on such principles reveals major features of the
genuinely high-energy one, first of all, it appears to be free from
ultra-violet divergences, even the self-energy loop terms become finite. Also
we discuss other arising interesting phenomena such as the high-gradient
currents and charges, unified ``all-in-one'' multi-mass states, VR symmetry,
regularization-without-renormalization of SM, etc.

</DOC>
<DOC>
<DOCNO> 118635 </DOCNO>
The origin of cosmic rays: What can GLAST say ?


  Gamma rays in the band from 30 MeV to 300 GeV, used in combination with
direct measurements and with data from radio and X-ray bands, provide a
powerful tool for studying the origin of Galactic cosmic rays. Gamma-ray Large
Area Space Telescope (GLAST) with its fine 10-20 arcmin angular resolution will
be able to map the sites of acceleration of cosmic rays and their interactions
with interstellar matter. It will provide information that is necessary to
study the acceleration of energetic particles in supernova shocks, their
transport in the interstellar medium and penetration into molecular clouds.

</DOC>
<DOC>
<DOCNO> 178457 </DOCNO>
In-medium Pion-Pion Interaction and Chiral Symmetry Restoration


  We discuss medium modifications of the unitarized pion-pion interaction in
the nuclear medium. We incorporate both the effects of chiral symmetry
restoration and the influence of collective nuclear pionic modes, originating
from the p-wave coupling of the pion to delta-hole configurations. We show how
the resulting strong enhancement of the sigma-meson spectral function is
related to large fluctuations of the condensate associated with the partial
restoration of chiral symmetry.

</DOC>
<DOC>
<DOCNO> 118446 </DOCNO>
Monte Carlo inversion of hydrogen and metal lines from QSO absorption


  A new method, based on the simulated annealing algorithm and aimed at the
inverse problem in the analysis of intergalactic (interstellar) complex spectra
of hydrogen and metal lines, is presented. We consider the process of line
formation in clumpy stochastic media accounting for fluctuating velocity and
density fields (mesoturbulence). This approach generalizes our previous Reverse
Monte Carlo and Entropy-Regularized Minimization methods which were applied to
velocity fluctuations only. The method allows one to estimate, from an observed
system of spectral lines, both the physical parameters of the absorbing gas and
appropriate structures of the velocity and density distributions along the line
of sight. The validity of the computational procedure is demonstrated using a
series of synthetic spectra that emulate the up-to-date best quality data. HI,
CII, SiII, CIV, SiIV, and OVI lines, exhibiting complex profiles, were fitted
simultaneously. The adopted physical parameters have been recovered with a
sufficiently high accuracy. The results obtained encourage the application of
the proposed procedure to the analysis of real observational data.

</DOC>
<DOC>
<DOCNO> 119379 </DOCNO>
Formulas for direct determination of real speed in Galactic superluminal


  In this paper we show explicit and direct relations between the expected
quantities and the observed quantities for the components of Galactic
superluminal sources. Basic formulas for calculating the real speed and the
angle to the line of sight of the components from the data of proper motions
and the distance of the source are presented. We point out that the real speed
and the angle to the line of sight of components can be uniquely and directly
determined from the observed values of the proper motions and the distance of
the source. It is not necessary to calculate an intermediate quantity first and
then using the resulted value to calculate the two required quantities. The
process of the calculation is simple, and in this way, some extra uncertainties
are avoided.

</DOC>
<DOC>
<DOCNO> 99989 </DOCNO>
A monopole homology of integral homology 3-spheres


  To an integral homology 3-sphere $Y$, we assign a well-defined $\Z$-graded
(monopole) homology $MH_*(Y, I_{\e}(\T; \e_0))$ whose construction in principle
follows from the instanton Floer theory with the dependence of the spectral
flow $I_{\e}(\T; \e_0)$, where $\T$ is the unique U(1)-reducible monopole of
the Seiberg-Witten equation on $Y$ and $\e_0$ is a reference perturbation
datum. The definition uses the moduli space of monopoles on $Y \x \R$
introduced by Seiberg-Witten in studying smooth 4-manifolds. We show that the
monopole homology $MH_*(Y, I_{\e}(\T; \e_0))$ is invariant among Riemannian
metrics with same $I_{\e}(\T; \e_0)$. This provides a chamber-like structure
for the monopole homology of integral homology 3-spheres. The assigned function
$MH_{SWF}: \{I_{\e}(\T; \e_0)\} \to \{MH_*(Y, I_{\e}(\T; \e_0))\}$ is a
topological invariant (as Seiberg-Witten-Floer Theory).

</DOC>
<DOC>
<DOCNO> 151253 </DOCNO>
Mesonic Spectrum of Two Dimensional Supersymmetric Theories


  We consider a bound state problem for a family of supersymmetric gauge
theories with fundamental matter. These theories can be obtained by a
dimensional reduction of supersymmetric QCD from three dimensions to 1+1 and
subsequent truncation of some of the fields. We find that the models without
adjoint scalar converge to well-defined continuum limits and calculate the
resulting spectra of these theories. We also find the critical value of
coupling at which an additional massless state is observed. By contrast, the
models containing adjoint scalars, seem to have a continuous mass spectrum in
the limit of infinite volume.

</DOC>
<DOC>
<DOCNO> 100359 </DOCNO>
The Derived Picard Group is a Locally Algebraic Group


  Let A be a finite dimensional algebra over an algebraically closed field K.
The derived Picard group DPic(A) is the group of two-sided tilting complexes
over A modulo isomorphism. We prove that DPic(A) is a locally algebraic group,
and its identity component is Out^0(A). If B is a derived Morita equivalent
algebra then DPic(A) is isomorphic to DPic(B) as locally algebraic groups. Our
results extend, and our based on, work of Huisgen-Zimmermann, Saorin and
Rouquier.

</DOC>
<DOC>
<DOCNO> 70211 </DOCNO>
The Lightest Strange Scalar Resonance


  I present the results of a recent calculation to determine the number of
strange scalar resonances below 1.8 GeV based on the analytic properties of the
experimental pi K scattering amplitude. Only one resonance was found in the
data, and this is readily identifiable as the K_0^*(1430). We found no evidence
to support the kappa(900).

</DOC>
<DOC>
<DOCNO> 10260 </DOCNO>
From spin-Peierls to superconductivity: (TMTTF)_2PF_6 under high


  The nature of the attractive electron-electron interaction, leading to the
formation of Cooper-pairs in unconventional superconductors has still to be
fully understood and is subject to intensive research. Here we show that the
sequence spin-Peierls, antiferromagnetism, superconductivity observed in
(TMTTF)_2PF_6 under pressure makes the (TM)_2X phase diagram universal. We
argue that the suppression of the spin-Peierls transition under pressure, the
close vicinity of antiferromagnetic and superconducting phases at high pressure
as well as the existence of critical antiferromagnetic fluctuations above T_c
strongly support the intriguing possibility that the interchain exchange of
antiferromagnetic fluctuations provides the pairing mechanism required for
bound charge carriers.

</DOC>
<DOC>
<DOCNO> 120704 </DOCNO>
X-Ray Lines from Hot Flows around White Dwarfs. Application to SS Cygni


  Rather than accreting via a disk, some White Dwarfs (WDs) in quiescent Dwarf
Novae (DN) could accrete via an Advection-Dominated Accretion Flow (ADAF)
possibly responsible for the X-ray Bremsstrahlung emission observed. Such a hot
accretion flow is also expected to produce characteristic thermal line
emission. Using SS Cyg as a specific example, we show that knowing a priori the
inclination and the WD mass in quiescent DN makes X-ray line diagnostics
powerful probes of the flow structure in these systems. Current X-ray
instruments can discriminate, from their width, between lines emitted from a
flow with a Keplerian rotation rate and those emitted at a substantially
sub-Keplerian rate. This could be used to observationally test the property of
energy advection, which is at the origin of the partial radial pressure support
by the hot gas and the sub-Keplerian rotation rate in an ADAF.

</DOC>
<DOC>
<DOCNO> 84379 </DOCNO>
Solutions of the spherically symmetric SU(2) Einstein-Yang-Mills


  It is shown analytically that every static, spherically symmetric solution to
the Einstein Yang Mills equations with SU(2) gauge group that is defined in the
far field has finite ADM mass. Moreover, there can be at most two horizons for
such solutions. The three types of solutions possible, Bartnik-McKinnon
particle-like solutions, Reissner-Nordstrom-like solutions, and black hole
solutions having only one horizon are distinguished by the behavior of the
metric coefficients at the origin.

</DOC>
<DOC>
<DOCNO> 99436 </DOCNO>
Level-one Highest Weight Representation of $U_q[\hat{sl(N|1)}]$ and


  We study the level-one irreducible highest weight representations of the
quantum affine superalgebra $U_q[\hat{sl(N|1)}]$, and calculate their
characters and supercharacters. We obtain bosonized q-vertex operators acting
on the irreducible $U_q[\hat{sl(N|1)}]$-modules and derive the exchange
relations satisfied by the vertex operators. We give the bosonization of the
multi-component super $t-J$ model by using the bosonized vertex operators.

</DOC>
<DOC>
<DOCNO> 121567 </DOCNO>
The Impact of External Tidal Fields on the ISM of Dwarf Spheroidals


  It was found that for three dwarf spheroidal galaxies - Sculptor, Tucana, and
Cetus - there is a correspondence between the distribution of associated HI gas
and the projected tidal axis direction. Numerical hydrodynamical simulations
confirmed the following scenario: SN Ia explosions remove most of the
interstellar medium beyond the tidal radius of the dwarf galaxy, with most of
the mass being in clouds moving along the principal tidal axis.

</DOC>
<DOC>
<DOCNO> 178622 </DOCNO>
Mean field theory for global binding systematics


  We review some possible improvements of mean field theory for application to
nuclear binding systematics. Up to now, microscopic theory has been less
successful than models starting from the liquid drop in describing accurately
the global binding systematics. We believe that there are good prospects to
develop a better global theory, using modern forms of energy density
functionals and treating correlation energies systematically by the RPA.

</DOC>
<DOC>
<DOCNO> 116948 </DOCNO>
GRECP/MRD-CI calculations of the spin-orbit splitting in the ground


  The generalized relativistic effective core potential (GRECP) approach is
employed in the framework of multireference single- and double-excitation
configuration interaction (MRD-CI) method to calculate the spin-orbit (SO)
splitting in the $^2P^o$ ground state of the Tl atom and spectroscopic
constants for the $0^+$ ground state of TlH. The 21-electron GRECP for Tl is
used and the outer core 5s and 5p pseudospinors are frozen with the help of the
level shift technique. The spin-orbit selection scheme with respect to
relativistic multireference states and the corresponding code are developed and
applied in the calculations. In this procedure both correlation and spin-orbit
interactions are taken into account. A [4,4,4,3,2] basis set is optimized for
the Tl atom and employed in the TlH calculations. Very good agreement is found
for the equilibrium distance, vibrational frequency, and dissociation energy of
the TlH ground state ($R_e=1.870 \AA, \omega_e=1420 cm^{-1}, D_e=2.049 eV$) as
compared with the experimental data ($R_e=1.868 \AA, \omega_e=1391 cm^{-1},
D_e=2.06 eV$).

</DOC>
<DOC>
<DOCNO> 117190 </DOCNO>
A path-integral approach to the collisional Boltzmann gas


  Collisional effects are included in the path-integral formulation that was
proposed in one of our previous paper for the collisionless Boltzmann gas. In
calculating the number of molecules entering a six-dimensional phase volume
element due to collisions, both the colliding molecules and the scattered
molecules are allowed to have distributions; thus the calculation is done
smoothly and no singularities arise.

</DOC>
<DOC>
<DOCNO> 121107 </DOCNO>
A Probabilistic Quantification of Galaxy Cluster Membership


  Clusters of galaxies are important laboratories for understanding both galaxy
evolution and constraining cosmological quantities. Any analysis of clusters,
however, is best done when one can reliably determine which galaxies are
members of the cluster. While this would ideally be done spectroscopically, the
difficulty in acquiring a complete sample of spectroscopic redshifts becomes
rather daunting, especially at high redshift where the background contamination
becomes increasingly larger. Traditionally, an alternative approach of applying
a statistical background correction has been utilized, which, while useful in a
global sense, does not provide information for specific galaxies. In this
paper, we develop a more robust technique which uses photometrically estimated
redshifts to determine cluster membership. This technique can either be used as
an improvement over the commonly used statistical correction method or it can
be used to determine cluster candidates on an individual galaxy basis. By
tuning the parameters of our algorithm, we can selectively maximize our
completeness or, alternatively, minimize our contamination. Furthermore, our
technique provides a statistical quantification of both our resulting
completeness and contamination from foreground and background galaxies.

</DOC>
<DOC>
<DOCNO> 8830 </DOCNO>
Investigation of thermal and magnetic properties of defects in a


  The specific heat, magnetic susceptibility and ESR signals of a Na-deficient
vanadate Na_xV_2O_5 (x=1.00 - 0.90) were studied in the temperature range 0.07
- 10 K, well below the transition point to a spin-gap state. The contribution
of defects provided by sodium vacancies to the specific heat was observed. It
has a low temperature part which does not tend to zero till at least 0.3 K and
a high temperature power-like tail appears above 2 K. Such dependence may
correspond to the existence of local modes and correlations between defects in
V-O layers. The magnetic measurements and ESR data reveal S=1/2 degrees of
freedom for the defects, with their effective number increasing in temperature
and under magnetic field. The latter results in the nonsaturating magnetization
at low temperature. No long-range magnetic ordering in the system of defects
was found. A model for the defects based on electron jumps near vacancies is
proposed to explain the observed effects. The concept of a frustrated
two-dimensional correlated magnet induced by the defects is considered to be
responsible for the absence of magnetic ordering.

</DOC>
<DOC>
<DOCNO> 70156 </DOCNO>
Logarithmic SUSY electroweak effects on four-fermion processes at TeV


  We compute the MSSM one-loop contributions to the asymptotic energy behaviour
of fermion-antifermion pair production at future lepton-antilepton colliders.
Besides the conventional logarithms of Renormalization Group origin, extra SUSY
linear logarithmic terms appear of "Sudakov-type". In the TeV range their
overall effect on a variety of observables can be quite relevant and
drastically different from that obtained in the SM case.

</DOC>
<DOC>
<DOCNO> 7651 </DOCNO>
Dimensional Crossover in Quasi One-Dimensional and High T_c


  The one-dimensional electron gas exhibits spin-charge separation and
power-law spectral responses to many experimentally relevant probes. Ordering
in a quasi one-dimensional system is necessarily associated with a dimensional
crossover, at which sharp quasiparticle peaks, with small spectral weight,
emerge from the incoherent background. Using methods of Abelian bosonization,
we derive asymptotically correct expressions for the spectral changes induced
by this crossover. Comparison is made with experiments on the high temperature
superconductors, which are electronically quasi one-dimensional on a local
scale.

</DOC>
<DOC>
<DOCNO> 68889 </DOCNO>
Status of the solution to the solar neutrino problem based on


  We analyze the current status of the solution to the solar neutrino problem
based both on: a) non-standard flavor changing neutrino interactions (FCNI) and
b) non-universal flavor diagonal neutrino interactions (FDNI). We find that
FCNI and FDNI with matter in the sun as well as in the earth provide a good fit
not only to the total rate measured by all solar neutrino experiments but also
to the day-night and seasonal variations of the event rate, as well as the
recoil electron energy spectrum measured by the SuperKamiokande collaboration.
This solution does not require massive neutrinos and neutrino mixing in vacuum.
Stringent experimental constraints on FCNI from bounds on lepton flavor
violating decays and on FDNI from limits on lepton universality violation rule
out $\nu_e \to \nu_\mu$ transitions induced by New Physics as a solution to the
solar neutrino problem. However, a solution involving $\nu_e \to \nu_\tau$
transitions is viable and could be tested independently by the upcoming
$B$-factories if flavor violating tau decays would be observed at a rate close
to the present upper bounds.

</DOC>
<DOC>
<DOCNO> 152342 </DOCNO>
Supercurrents in Matrix theory and the generalized AdS/CFT


  We investigate Matrix theory in the large-N limit following the conjectured
correspondence between Matrix theory and supergravity on the near-horizon limit
of the D0-brane background. We analyze the complete fermionic spectrum of
supergravity and obtain two-point functions of the supercurrents in Matrix
theory. By examining the large-N scaling properties of the correlators, we
discuss the consistency of the 11-dimensional interpretation of the
supersymmetry of Matrix theory.

</DOC>
<DOC>
<DOCNO> 39848 </DOCNO>
Excited Heavy Baryons and Their Symmetries I: Formalism


  This is the first of two papers to study a new emergent symmetry which
connects orbitally excited heavy baryons to the ground states in the combined
heavy quark and large $N_c$ limit. The existence of this symmetry is shown in a
model-independent way, and different possible realizations of the symmetry are
discussed. It is also proved that this emergent symmetry commutes with the
large $N_c$ spin-flavor symmetry.

</DOC>
<DOC>
<DOCNO> 9026 </DOCNO>
Alternative Buffer-Layers for the Growth of SrBi2Ta2O9 on Silicon


  In this work we investigate the influence of the use of YSZ and CeO2/YSZ as
insulators for Metal- Ferroelectric-Insulator-Semiconductor (MFIS) structures
made with SrBi2Ta2O9 (SBT). We show that by using YSZ only the a-axis oriented
Pyrochlore phase could be obtained. On the other hand the use of a CeO2/YSZ
double-buffer layer gave a c-axis oriented SBT with no amorphous SiO2 inter-
diffusion layer. The characteristics of MFIS diodes were greatly improved by
the use of the double buffer. Using the same deposition conditions the memory
window could be increased from 0.3 V to 0.9 V. From the piezoelectric response,
nano-meter scale ferroelectric domains could be clearly identified in SBT thin
films.

</DOC>
<DOC>
<DOCNO> 85035 </DOCNO>
Making classical and quantum canonical general relativity computable


  We consider general relativity with a cosmological constant as a perturbative
expansion around a completely solvable diffeomorphism invariant field theory.
This theory is the $\Lambda\to\infty$ limit of general relativity. This allows
an explicit perturbative computational setup in which the quantum states of the
theory and the classical observables can be explicitly computed. The zeroth
order corresponds to highly degenerate space-times with vanishing volume.
Perturbations give rise to space-times with non-vanishing volumes in a natural
way. The spectrum of area- and volume-related observables constructed by
coupling the theory to matter can be directly assessed. An unexpected
relationship arises at a quantum level between the discrete spectrum of the
volume operator and the allowed values of the cosmological constant.

</DOC>
<DOC>
<DOCNO> 122283 </DOCNO>
Observation of X-ray lines from a Gamma-Ray Burst (GRB991216): Evidence


  We report on the discovery of two emission features observed in the X-ray
spectrum of the afterglow of the gamma-ray burst (GRB) of 16 Dec. 1999 by the
Chandra X-Ray Observatory. These features are identified with the Ly$_{\alpha}$
line and the narrow recombination continuum by hydrogenic ions of iron at a
redshift $z=1.00\pm0.02$, providing an unambiguous measurement of the distance
of a GRB. Line width and intensity imply that the progenitor of the GRB was a
massive star system that ejected, before the GRB event, $\approx 0.01 \Ms$ of
iron at a velocity $\approx 0.1 c$, probably by a supernova explosion.

</DOC>
<DOC>
<DOCNO> 120070 </DOCNO>
Disk-galaxy density distribution from orbital speeds using Newton's law,


  Given the dimensions(including thickness) of an axisymmetric galaxy, Newton's
law is used in integral form to find the density distributions required to
match a wide range of orbital speed profiles. Newton's law is not modified and
no dark-matter halos are required. The speed distributions can have extreme
shapes if they are reasonably smooth. Several examples are given.

</DOC>
<DOC>
<DOCNO> 151292 </DOCNO>
Fusion and Analytical Bethe Ansatz for the $A_{\n-1}^{(1)}$ Open Spin


  We generalise the fusion procedure for the $A_{\n-1}^{(1)}$ open spin chain
($\n>2$) and we show that the transfer matrix satisfies a crossing property. We
use these results to solve the $A_{\n-1}^{(1)}$ open spin chain with $U_{q}
(SU(\n))$ symmetry by means of the analytical Bethe ansatz method. Our results
coincide with the known ones obtained by means of the nested Bethe ansatz.

</DOC>
<DOC>
<DOCNO> 123155 </DOCNO>
Deep Blazar Surveys


  I address the need for deep blazar surveys by showing that our current
understanding of blazars is based on a relatively small number of intrinsically
luminous sources. I then review the on-going deeper surveys, addressing in
particular their limits and limitations. Finally, I present some preliminary
results on the evolutionary properties of faint blazars as derived from the
Deep X-ray Radio Blazar Survey (DXRBS).

</DOC>
<DOC>
<DOCNO> 102715 </DOCNO>
Stochastic Differential Geometry and the Random Flows of Viscous and


  We integrate in closed implicit form the Navier-Stokes equations for an
incompressible fluid and the kinematical dynamo equation, in smooth manifolds
and Euclidean space. This integration is carried out by applying Stochastic
Differential Geometry, i.e. the gauge-theoretical formulation of Brownian
motions. Non-Riemannian geometries with torsion of the trace-type are found to
have a fundamental role. We prove that in any dimension other than 1, the
Navier-Stokes equations can be represented as a purely diffusive process, while
we can also give a random lagrangian representation for the diffusion of
vorticity and velocity in terms of the non-Riemannian geometry.

</DOC>
<DOC>
<DOCNO> 71490 </DOCNO>
Non-factorizable contributions in B decays revisited


  Two-body decays of B mesons are studied by decomposing their amplitude into a
sum of factorizable and non-factorizable ones. The former is estimated by using
the naive factorization while the latter is calculated by using a hard pion (or
kaon) approximation in the infinite momentum frame. It is seen that the
non-factorizable contribution is small but not negligible in color favored
decays while it is more important in color mismatched decays.

</DOC>
<DOC>
<DOCNO> 150478 </DOCNO>
Canonical Quantization and Topological Theories


  The canonical quantization of the topological particle is described; it is
shown that BRST quantization of the model gives the supersymmetric quantum
mechanical model considered by Witten when investigating Morse theory, and the
rigorous path integral method appropriate for this model is discussed.
Possibilities for the extension of this work to two dimensional models are
briefly considered.

</DOC>
<DOC>
<DOCNO> 101969 </DOCNO>
Lifting Grobner bases from the exterior algebra


  In the article "Non-commutative Grobner bases for commutative algebras",
Eisenbud-Peeva-Sturmfels proved a number of results regarding Grobner bases and
initial ideals of those ideals in the free associative algebra which contain
the commutator ideal. We prove similar results for ideals which contains the
anti-commutator ideal (the defining ideal of the exterior algebra). We define
one notion of generic initial ideals in the free assoicative algebra, and show
that gin's of ideals containing the commutator ideal, or the anti-commutator
ideal, are finitely generated.

</DOC>
<DOC>
<DOCNO> 72175 </DOCNO>
New insights into the proton structure with ep collider HERA


  Since its commissioning in 1991, the ep collider HERA has been running
successfully for almost a decade without stopping improving its performance. In
this report, the inclusive cross section and structure function measurements
for the deep inelastic scattering of neutral and charged current processes in
the full HERA kinematic domain are reviewed. The results are compared with the
Standard Model expectations for the deep inelastic scattering processes. The
new insights into the proton structure and on the underlying strong and
electroweak interactions are discussed.

</DOC>
<DOC>
<DOCNO> 102473 </DOCNO>
Non-Abelian Geometry


  Spatial noncommutativity is similar and can even be related to the
non-Abelian nature of multiple D-branes. But they have so far seemed
independent of each other. Reflecting this decoupling, the algebra of matrix
valued fields on noncommutative space is thought to be the simple tensor
product of constant matrix algebra and the Moyal-Weyl deformation. We propose
scenarios in which the two become intertwined and inseparable. Therefore the
usual separation of ordinary or noncommutative space from the internal discrete
space responsible for non-Abelian symmetry is really the exceptional case of an
unified structure. We call it non-Abelian geometry. This general structure
emerges when multiple D-branes are configured suitably in a flat but varying B
field background, or in the presence of non-Abelian gauge field background. It
can also occur in connection with Taub-NUT geometry. We compute the deformed
product of matrix valued functions using the lattice string quantum mechanical
model developed earlier. The result is a new type of associative algebra
defining non-Abelian geometry. Possible supergravity dual is also discussed.

</DOC>
<DOC>
<DOCNO> 150495 </DOCNO>
The M(atrix) model of M-theory


  These lecture notes give a pedagogical and (mostly) self-contained review of
some basic aspects of the Matrix model of M-theory. The derivations of the
model as a regularized supermembrane theory and as the discrete light-cone
quantization of M-theory are presented. The construction of M-theory objects
from matrices is described, and gravitational interactions between these
objects are derived using Yang-Mills perturbation theory. Generalizations of
the model to compact and curved space-times are discussed, and the current
status of the theory is reviewed.

</DOC>
<DOC>
<DOCNO> 116348 </DOCNO>
Can Science `explain' Consciousness ?


  Consciousness is the process by which one attributes `meaning' to the world.
Considering F$\phi$llesdal's definition of `meaning' as the joint product of
all `evidence' that is available to those who `communicate', we conclude that
science can, not only reduce all the {\em evidence} to a Basic Entity (we call
BE), but also can `explain' consciousness once a suitable definition for {\em
communication} is found that exploits the quantum superposition principle to
incorporate the fuzzyness of our experience. Consciousness may be beyond
`computability', but it is not beyond `communicability'.

</DOC>
<DOC>
<DOCNO> 121416 </DOCNO>
Unusual Properties of X-Ray Emission near the Galactic Center


  The X-ray spectrum in a $1^{\circ}\times1^{\circ}$ region of the Galactic
center observed with the ASCA satellite is examined in detail, following the
first report by Koyama et al. (1996, AAA 65.155.208). The observed spectrum
contains prominent emission lines from helium-like and hydrogen-like ions of
various elements, and is essentially the same all over the region. If the
observed spectrum is thermal emission from hot plasmas, it requires
multi-temperature plasma components, each at a different degree of ionization
and with a different amount of absorption. The absence of adiabatic cooling and
of systematic changes in the degree of ionization over the region is against
the Galactic center origin of hot plasmas. A significant broadening of the
helium-like and hydrogen-like iron K-lines is confirmed. The line width
corresponds to a rms velocity of $\sim3300$ km~s$^{-1}$, which far exceeds the
sound velocity in a plasma of $kT\sim14$ keV measured with the Ginga satellite.
These facts cast doubt on a thermal origin of the observed X-ray emission.

</DOC>
<DOC>
<DOCNO> 119118 </DOCNO>
On the Two-Phase Structure of Protogalactic Clouds


  Within protogalaxies, thermal instability leads to the formation of a
population of cool fragments, confined by the pressure of residual hot gas. The
hot gas remains in quasi-hydrostatic equilibrium, at approximately the virial
temperature of the dark matter halo. It is heated by compression and shock
dissipation and is cooled by bremsstrahlung emission and conductive losses into
the cool clouds. The cool fragments are photoionized and heated by the
extragalactic UV background and nearby massive stars. The smallest clouds are
evaporated due to conductive heat transfer from the hot gas. All are subject to
disruption due to hydrodynamic instabilities. They also gain mass due to
collisions and mergers and condensation from the hot gas due to conduction. The
size distribution of the fragments in turn determines the rate and efficiency
of star formation during the early phase of galactic evolution. We have
performed one-dimensional hydrodynamic simulations of the evolution of the hot
and cool gas. The cool clouds are assumed to follow a power-law size
distribution, and fall into the galactic potential, subject to drag from the
hot gas. The relative amounts of the hot and cool gas is determined by the
processes discussed above, and star formation occurs at a rate sufficient to
maintain the cool clouds at 10$^4$ K. We present density distributions for the
two phases and also for the stars for several cases, parametrized by the
circular speeds of the potentials. Under some conditions, primarily low
densities of the hot gas, conduction is more efficient than radiative processes
at cooling the hot gas, limiting the x-ray radiation from the halo gas.

</DOC>
<DOC>
<DOCNO> 121787 </DOCNO>
On the Origin of Intrinsic Narrow Absorption Lines in z<1 QSOs


  We present a statistical analysis of the associated, high ionization narrow
absorption line (NAL) systems in a sample of 59 QSOs defined from the HST QSO
Absorption Line Key Project. We have compiled the QSO luminosities at 2500 A, 5
GHz, and 2 keV, spectral indices at 2500 A and 5 GHz, the H-beta emission line
FWHM, the CIV emission line FWHM, and the radio core fraction. We find 17
associated NALs toward 15 QSOs, of which ~10 are statistically expected to be
intrinsic. From a multivariate clustering analysis, the QSOs seem to group
together based primarily on radio luminosity, followed by radio spectral index,
CIV emission line FWHM, and soft X-ray luminosity. Radio-loud QSOs which have
compact radio morphologies, flat radio spectra, and mediocre CIV FWHM (<6000
km/s) do not have detectable associated NALs, down to REW(CIV)=0.35 A. We find
that BALQSOs have an enhanced probability of hosting detectable NAL gas and
that the velocities of associated NALs are peaked around the emission
redshifts, rather than the systemic redshifts of the QSOs. There is only one
strong NAL [REW(CIV)>1.5 A] in our low redshift sample which implies evolution
in the number of strong NALs with redshift. We interpret these results in the
context of an accretion-disk model. In this framework, we suggest that the
observational clues result from differences in orientation and wind properties,
the latter presumably associated with the QSO radio properties. (abridged)

</DOC>
<DOC>
<DOCNO> 121612 </DOCNO>
Optical Spectroscopy Of The X-Ray Transient XTE J1118+480 In Outburst


  We report on optical spectroscopic observations of the X-ray Transient XTE
J1118+480 covering the period from April 7, 2000 to July 4, 2000. The spectrum
is characterized by weak, broad, double-peaked Balmer and He lines on top of a
blue continuum of slope p ~ 1/3, as expected for an optically-thick accretion
disk. The weak Bowen blend seen in our spectra may indicate a low intrinsic
metallicity for the source. The presence of a partial S-wave pattern in the
HeII lambda-4686 line appears consistent with the reported photometric orbital
period Porb = 4.1 hr for XTE J1118+480. By using a combination of Doppler
mapping and various theoretical arguments, we constrain plausible orbital
parameters for the system: a mass ratio 0.02 <~ q <~ 0.1, an inclination i >~
70 deg for a neutron star primary, or 30 deg <~ i <~ 50 deg for a black hole
primary with a mass between 4 and 10 Msun. CaII absorption features observed at
very high resolution constrain the interstellar hydrogen absorption column
log[N_HI (cm^{-2})] ~ 20.45 +/- 0.2 and the identification of three absorbing
clouds indicate a distance to the source <~ 1 kpc, assuming the line-of-sight
to XTE J1118+480 has average high-latitude properties. These results are
discussed in the context of previous multiwavelength observations of this
unusual system.

</DOC>
<DOC>
<DOCNO> 40608 </DOCNO>
Electrooptical Detection of Charged Particle Beams


  We have made the first observation of a charged particle beam by means of its
electro-optical effect on the propagation of laser light in a birefringent
crystal at the Brookhaven National Laboratory Accelerator Test Facility.
Polarized infrared light was coupled to a LiNbO3 crystal through a polarization
maintaining fiber of 4 micron diameter. An electron beam in 10ps bunches of 1mm
diameter was scanned across the crystal. The modulation of the laser light
during passage of the electron beam was observed using a photodiode with 45GHz
bandwidth. The fastest rise time measured, 120ps, was made in the single shot
mode and was limited by the bandwidth of the oscilloscope and the associated
electronics. Both polarization dependent and polarization independent effects
were observed. This technology holds promise of greatly improved spatial and
temporal resolution of charged particle beams.

</DOC>
<DOC>
<DOCNO> 68342 </DOCNO>
Quantum Creation of Closed Universe with Both Effects of Tunneling and


  A new ''twice loose shoe'' method in the Wheeler-DeWitt equation of the
universe wave function on the cosmic scale factor a and a scalar field $\phi$
is suggested in this letter. We analysis the both affects come from the
tunneling effect of a and the potential well effect of $\phi$, and obtain the
initial values $a_0$ and $\phi_0$ about a primary closed universe which is born
with the largest probability in the quantum manner. Our result is able to
overcome the ''large field difficulty'' of the universe quantum creation
probability with only tunneling effect. This new born universe has to suffer a
startup of inflation, and then comes into the usual slow rolling inflation. The
universe with the largest probability maybe has a ''gentle'' inflation or an
eternal chaotic inflation, this depends on a new parameter q which describes
the tunneling character.

</DOC>
<DOC>
<DOCNO> 13092 </DOCNO>
Fractionnally charged excitations in the charge density wave state of a


  Elementary excitations of the 4k$_F$ charge density wave state of a
quarter-filled strongly correlated electronic one-dimensional chain are
investigated in the presence of dispersionless quantum optical phonons using
Density Matrix Renormalization Group techniques. Such excitations are shown to
be topological unbound solitons carrying charge $e/2$. Relevance to the 4k$_F$
charge density wave instability in $\rm (DI-DCNQI)_2Ag$ or recently discovered
in (TMTTF)$_2$X (X=PF$_6$, AsF$_6$) is discussed.

</DOC>
<DOC>
<DOCNO> 68806 </DOCNO>
General Properties of the Self-tuning Domain Wall Approach to the


  We study the dynamics of brane worlds coupled to a scalar field and gravity,
and find that self-tuning of the cosmological constant is generic in theories
with at most two branes or a single brane with orbifold boundary conditions. We
demonstrate that singularities are generic in the self-tuned solutions
compatible with localized gravity on the brane: we show that localized gravity
with an infinitely large extra dimension is only consistent with particular
fine-tuned values of the brane tension. The number of allowed brane tension
values is related to the number of negative stationary points of the scalar
bulk potential and, in the case of an oscillatory potential, the brane tension
for which gravity is localized without singularities is quantized. We also
examine a resolution of the singularities, and find that fine-tuning is
generically re-introduced at the singularities in order to retain a static
solution. However, we speculate that the presence of additional fields may
restore self-tuning.

</DOC>
<DOC>
<DOCNO> 101027 </DOCNO>
Rademacher chaos in symmetric spaces,2


  It is shown that a specific ordering of the Rademacher chaos leads to a basic
sequence in a wide class of symmetric spaces on the segment [0,1]. Necessary
and sufficient conditions on a such space are found for Rademacher chaos to
possess the unconditionality property.

</DOC>
<DOC>
<DOCNO> 102077 </DOCNO>
Spaces of embeddings of compact polyhedra into 2-manifolds


  Let M be a PL 2-manifold and X be a compact subpolyhedron of M and let E(X,
M) denote the space of embeddings of X into M with the compact-open topology.
In this paper we study an extension property of embeddings of X into M and show
that the restriction map from the homeomorphism group of M to E(X, M) is a
principal bundle. As an application we show that if M is a Euclidean PL
2-manifold and dim X >= 1 then the triple (E(X,M), E^LIP(X,M), E^PL(X, M)) is
an (s,Sigma,sigma)-manifold, where E_K^LIP(X,M) and E_K^PL(X, M) denote the
subspaces of Lipschitz and PL embeddings.

</DOC>
<DOC>
<DOCNO> 70110 </DOCNO>
Short-Baseline Neutrino Oscillations at a Neutrino Factory


  Within the framework of three-neutrino and four-neutrino scenarios that can
describe the results of the LSND experiment, we consider the capabilities of
short baseline neutrino oscillation experiments at a neutrino factory. We find
that, when short baseline ($L \alt 100$ km) neutrino factory measurements are
used together with other accelerator-based oscillation results, the complete
three-neutrino parameter space can best be determined by measuring the rate of
$\nu_e \to \nu_\tau$ oscillations, and measuring CP violation with either
$\nu_e \to \nu_\mu$ or $\nu_\mu \to \nu_\tau$ oscillations (including the
corresponding antineutrino channels). With measurements of CP violation in both
$\nu_e \to \nu_\mu$ and $\nu_\mu \to \nu_\tau$ it may be possible to
distinguish between the three- and four-neutrino cases.

</DOC>
<DOC>
<DOCNO> 8889 </DOCNO>
Magnetic and electrical resistance behaviour of the oxides,


  We have investigated the magnetic and electrical resistance behaviour of
 Ca$_{3-x}$Y$_x$LiRuO$_6$. The parent compound exhibits magnetic ordering from
Ru sublattice at a rather high temperature, 113 K. Though the paramagnetic
 Curie temperature ($\theta$$_p$) is negative indicative of antiferromagnetic
ordering, the large magnitude (-250 K) of $\theta$$_p$ reveals complex nature
of the magnetism in this compound. Ru ions appear to be in the pentavalent
state. We note that the N\'eel temperature undergoes only a marginal reduction
by Y substitution. All these compositions are found to be insulators and thus
the electron doping does not result in metallicity. Thus the overall magnetic
and transport behaviour are found to be essentially insensitive to Y
substitution for Ca, a finding which may favour the idea of
quasi-one-dimensional magnetism in these compounds.

</DOC>
<DOC>
<DOCNO> 69852 </DOCNO>
Supergravity and a Confining Gauge Theory: Duality Cascades and


  We revisit the singular IIB supergravity solution describing M fractional
3-branes on the conifold [hep-th/0002159]. Its 5-form flux decreases, which we
explain by showing that the relevant \NN=1 SUSY SU(N+M)xSU(N) gauge theory
undergoes repeated Seiberg-duality transformations in which N -> N-M. Far in
the IR the gauge theory confines; its chiral symmetry breaking removes the
singularity of hep-th/0002159 by deforming the conifold. We propose a
non-singular pure-supergravity background dual to the field theory on all
scales, with small curvature everywhere if the `t Hooft coupling g_s M is
large. In the UV it approaches that of hep-th/0002159, incorporating the
logarithmic flow of couplings. In the IR the deformation of the conifold gives
a geometrical realization of chiral symmetry breaking and confinement. We
suggest that pure \NN=1 Yang-Mills may be dual to strings propagating at small
g_s M on a warped deformed conifold. We note also that the standard model
itself may lie at the base of a duality cascade.

</DOC>
<DOC>
<DOCNO> 102725 </DOCNO>
On Stieltjes relations, Painlev\'e-IV hierarchy and complex monodromy


  A generalisation of the Stieltjes relations for the Painlev\'e-IV
transcendents and their higher analogues determined by the dressing chains is
proposed. It is proven that if a rational function from a certain class
satisfies these relations it must be a solution of some higher Painlev\'e-IV
equation. The approach is based on the interpretation of the Stieltjes
relations as local trivial monodromy conditions for certain Schr\"odinger
equations in the complex domain. As a corollary a new class of the
Schr\"odinger operators with trivial monodromy is constructed in terms of the
Painlev\'e-IV transcendents.

</DOC>
<DOC>
<DOCNO> 122029 </DOCNO>
Detection of arcs in Saturn's F ring during the 1995 Sun ring-plane


  Observations of the November 1995 Sun crossing of the Saturn's ring-plane
made with the 3.6m CFH telescope, using the UHAO adaptive optics system, are
presented here. We report the detection of four arcs located in the vicinity of
the F ring. They can be seen one day later in HST images. The combination of
both data sets gives accurate determinations of their orbits. Semi-major axes
range from 140020 km to 140080 km, with a mean of 140060 +- 60 km. This is
about 150 km smaller than previous estimates of the F ring radius from Voyager
1 and 2 data, but close to the orbit of another arc observed at the same epoch
in HST images.

</DOC>
<DOC>
<DOCNO> 174494 </DOCNO>
Observation of Direct Photons in Central 158 A GeV 208Pb+208Pb


  A measurement of direct photon production in 208Pb + 208Pb collisions at 158
A GeV has been carried out in the CERN WA98 experiment. The invariant yield of
direct photons in central collisions is extracted as a function of transverse
momentum in the interval 0.5 < p_T < 4 GeV/c. A significant direct photon
signal, compared to statistical and systematical errors, is seen at p_T > 1.5
GeV/c. The results constitute the first observation of direct photons in
ultrarelativistic heavy-ion collisions which could be significant for diagnosis
of quark gluon plasma formation.

</DOC>
<DOC>
<DOCNO> 85063 </DOCNO>
Scalar field collapse in three-dimensional AdS spacetime


  We describe results of a numerical calculation of circularly symmetric scalar
field collapse in three spacetime dimensions with negative cosmological
constant. The procedure uses a double null formulation of the Einstein-scalar
equations. We see evidence of black hole formation on first implosion of a
scalar pulse if the initial pulse amplitude $A$ is greater than a critical
value $A_*$. Sufficiently near criticality the apparent horizon radius $r_{AH}$
grows with pulse amplitude according to the formula $r_{AH} \sim
(A-A_*)^{0.81}$.

</DOC>
<DOC>
<DOCNO> 71792 </DOCNO>
Equilibrium and nonequilibrium properties associated with the chiral


  We study the dynamics of the chiral phase transition at finite density in the
Gross-Neveu (GN) model in the leading order in large-N approximation. The phase
structure of the GN model in this approximation has the property that there is
a tricritical point at a fixed temperature and chemical potential separating
regions where the chiral transition is first order from that where it is second
order. We consider evolutions starting in local thermal and chemical
equilibrium in the massless unbroken phase for conditions pertaining to
traversing a first or second order phase transition. We assume boost invariant
kinematics and determine the evolution of the order parameter $\sigma$, the
energy density and pressure as well as the effective temperature, chemical
potential and interpolating number densities as a function of the proper time
$\tau$. We find that before the phase transition, the system behaves as if it
were an ideal fluid in local thermal equilibrium with equation of state
$p=\epsilon$. After the phase transition, the system quickly reaches its true
broken symmetry vacuum value for the fermion mass and for the energy density.
The single particle distribution functions for Fermions and anti-Fermions go
far out of equilibrium as soon as the plasma traverses the chiral phase
transition. We have also determined the spatial dependence of the "pion"
Green's function $<\bar{\psi}(x) \gamma_5 \psi(x) \bar{\psi}(0) \gamma_5
\psi(0)>$ as a function of the proper time.

</DOC>
<DOC>
<DOCNO> 71459 </DOCNO>
B Physics and CP Violation


  After an introduction to the Standard-Model description of CP violation and a
brief look at the present status of this phenomenon in the kaon system, a
classification of non-leptonic B-decays is given and the formalism of
$B^0_{d,s}$--$\bar{B^0_{d,s}}$ mixing is discussed. We then turn to the
$B$-factory benchmark modes, CP violation in charged B decays, and the
$B_s$-meson system. Finally, we focus both on $B\to\pi K$ decays, which play an
important role to probe the CKM angle $\gamma$, and on the $B_d\to\pi^+\pi^-$,
$B_s\to K^+K^-$ system, which allows an interesting determination of $\beta$
and $\gamma$.

</DOC>
<DOC>
<DOCNO> 7957 </DOCNO>
Nonadiabatic Landau Zener tunneling in Fe_8 molecular nanomagnets


  The Landau Zener method allows to measure very small tunnel splittings \Delta
in molecular clusters Fe_8. The observed oscillations of \Delta as a function
of the magnetic field applied along the hard anisotropy axis are explained in
terms of topological quantum interference of two tunnel paths of opposite
windings. Studies of the temperature dependence of the Landau Zener transition
rate P gives access to the topological quantum interference between exited spin
levels. The influence of nuclear spins is demonstrated by comparing P of the
standard Fe_8 sample with two isotopically substituted samples. The need of a
generalized Landau Zener transition rate theory is shown.

</DOC>
<DOC>
<DOCNO> 122819 </DOCNO>
A study of the gravitational wave form from pulsars


  We present analytical and numerical studies of the Fourier transform (FT) of
the gravitational wave (GW) signal from a pulsar,taking into account the
rotation of the Earth for a one day observation period.

</DOC>
<DOC>
<DOCNO> 169567 </DOCNO>
Quantum Mechanics As A Limiting Case of Classical Mechanics


  In spite of its popularity, it has not been possible to vindicate the
conventional wisdom that classical mechanics is a limiting case of quantum
mechanics. The purpose of the present paper is to offer an alternative point of
view in which quantum mechanics emerges as a limiting case of classical
mechanics in which the classical system is decoupled from its environment.

</DOC>
<DOC>
<DOCNO> 80717 </DOCNO>
Lattice Gauge Theory - QCD from Quarks to Hadrons


  Lattice Gauge Theory enables an ab initio study of the low-energy properties
of Quantum Chromodynamics, the theory of the strong interaction. I begin these
lectures by presenting the lattice formulation of QCD, and then outline the
benchmark calculation of lattice QCD, the light-hadron spectrum. I then proceed
to explore the predictive power of lattice QCD, in particular as it pertains to
hadronic physics. I will discuss the spectrum of glueballs, exotics and excited
states, before investigating the study of form factors and structure functions.
I will conclude by showing how lattice QCD can be used to study multi-hadron
systems, and in particular provide insight into the nucleon-nucleon
interaction.

</DOC>
<DOC>
<DOCNO> 80606 </DOCNO>
Green's Function Monte Carlo study of correlation functions in the


  A ``forward walking'' Quantum Monte Carlo (QMC) algorithm has been developed
to calculate correlation functions for the Hamiltonian lattice formulation of
U(1) Yang-Mills theory in (2+1) dimensions. It is shown that Wilson loops can
be calculated with high accuracy. Creutz ratios are used to determine the
string tension, which agrees with results from other approaches. Timelike
correlations are used to estimate the mass gaps, which agree with series
expansion results in the strong coupling regime.

</DOC>
<DOC>
<DOCNO> 68858 </DOCNO>
Logarithms of alpha in QED bound states from the renormalization group


  The velocity renormalization group is used to determine ln(alpha)
contributions to QED bound state energies. The leading order anomalous
dimension for the potential gives the alpha^5 ln(alpha) Bethe logarithm in the
Lamb shift. The next-to-leading order anomalous dimension determines the
alpha^6 ln(alpha), alpha^7 ln^2(alpha), and alpha^8 ln^3 (alpha) corrections to
the energy. These are used to obtain the alpha^8 ln^3(alpha) Lamb shift and
alpha^7 ln^2(alpha) hyperfine splitting for Hydrogen, muonium and positronium,
as well as the alpha^2 ln(alpha) and alpha^3 ln^2(alpha) corrections to the
ortho- and para-positronium lifetimes.

</DOC>
<DOC>
<DOCNO> 178992 </DOCNO>
Ground-state properties and spins of the odd {\boldmath$Z=N+1$} nuclei


  Binding energies, quadrupole deformation parameters, spins and parities of
the neutron-deficient odd $Z=N+1$ nuclei in the $A\sim 80$ region are
calculated in the relativistic mean field approximation. The ground-state and
low-lying configurations of the recently observed $^{77}$Y, $^{79}$Zr and
$^{83}$Mo nuclei are analyzed. The calculated results are compared with other
theoretical predictions.

</DOC>
<DOC>
<DOCNO> 120994 </DOCNO>
Dynamical Evolution: Spirals and Bars


  Non-axisymmetric modes like spirals and bars are the main driver of the
evolution of disks, in transferring angular momentum, and allowing mass
accretion. This evolution proceeds through self-regulation and feedback
mechanisms, such as bar destruction or weakening by a central mass
concentration, decoupling of a nuclear bar taking over the gas radial flows and
mass accretion, etc.. These internal mechanisms can also be triggered by
interaction with the environment. Recent problems are discussed, like the
influence of counter-rotation in the m=1 and m=2 patterns development and on
mass accretion by a central AGN.

</DOC>
<DOC>
<DOCNO> 40372 </DOCNO>
First Measurement of the Branching Fraction of the Decay psi(2S) --> tau


  The branching fraction of the psi(2S) decay into tau pair has been measured
for the first time using the BES detector at the Beijing Electron-Positron
Collider. The result is $B_{\tau\tau}=(2.71\pm 0.43 \pm 0.55) \times 10^{-3}$,
where the first error is statistical and the second is systematic. This value,
along with those for the branching fractions into e+e- and mu+mu of this
resonance, satisfy well the relation predicted by the sequential lepton
hypothesis. Combining all these values with the leptonic width of the resonance
the total width of the psi(2S) is determined to be $(252 \pm 37)$ keV.

</DOC>
<DOC>
<DOCNO> 9767 </DOCNO>
The Structure of a Quantized Vortex in a Bose-Einstein Condensate


  The structure of a quantized vortex in a Bose-Einstein Condensate is
investigated using the projection method developed by Peierls, Yoccoz, and
Thouless. This method was invented to describe the collective motion of a
many-body system beyond the mean-field approximation. The quantum fluctuation
has been properly built into the variational wave function, and a vortex is
described by a linear combination of Feynman wave functions weighted by a
Gaussian distribution in their positions. In contrast to the solution of the
Gross-Pitaevskii equation, the particle density is finite at the vortex axis
and the vorticity is distributed in the core region.

</DOC>
<DOC>
<DOCNO> 121517 </DOCNO>
Depletion of background galaxies due to the cluster lens CL0024+1654: U


  We have obtained U and R band observations of the depletion of background
galaxies due to the gravitational lensing of the galaxy cluster CL0024+1654
(z=0.39). The radial depletion curves show a significant depletion in both
bands within a radius of 40''-70'' from the cluster center. This is the first
time depletion is detected in the U band. This gives independent evidence for a
break in the slope of the U band luminosity function at faint magnitudes. The
radially averaged R band depletion curve is broader and deeper than in the U
band. The differences can be attributed to the wavelength dependence of the
slope of the luminosity function and to the different redshift distribution of
the objects probed in the two bands. We estimate the Einstein radius of a
singular isothermal sphere lens model using maximum likelihood analysis.
Adopting a slope of the number counts of 0.2 and using the background density
found beyond 150'' from the cluster center we find an Einstein radius of
17''+/-3'' and 25''+/-3'' in the U and R band, respectively. When combined with
the redshift of the single background galaxy at z=1.675 seen as four giant arcs
around 30'' from the cluster center, these values indicate a median redshift in
the range 0.7 to 1.1 for the U_AB > 24 mag and R_AB > 24 mag populations.

</DOC>
<DOC>
<DOCNO> 121847 </DOCNO>
X-Ray Photoabsorption in KLL Resonances of O VI And Abundance Analysis


  It is shown that photoabsorption via autoionizing resonances may be
appreciable and used for abundance analysis. Analogous to spectral lines, the
`resonance oscillator strength' f_r may be defined and evaluated in terms of
the differential oscillator strength df/d(epsilon) that relates bound and
continuum absorption. X-ray photoabsorption in KLL (1s2s2p) resonances of O VI
is investigated using highly resolved relativistic photoionization cross
sections with fine structure. It is found that f_r is comparable to that for UV
dipole transition in O VI (2s - 2p) and the X-ray (1s^2 ^1S_0 - 1s2p ^1P^o_1)
transition in O VII. The dominant O VI(KLL) components lie at 22.05 and 21.87
Angstroms. These predicted absorption features should be detectable by the
Chandra X-Ray Observatory (CXO) and the X-Ray Multi-Mirror Mission (XMM). The
combined UV/X-ray spectra of O VI/O VII should yield valuable information on
the ionization structure and abundances in sources such as the `warm absorber'
region of active galactic nuclei and the hot intergalactic medium. Some general
implications of resonant photoabsorption are addressed.

</DOC>
<DOC>
<DOCNO> 12642 </DOCNO>
Landau diamagnetism within nonextensive statistical thermodynamics


  In this paper, Landau diamagnetism is revisited in the context of
nonextensive statistical thermodynamics. Exact as well as approximate
expressions for partition function, magnetization and susceptibility are
obtained by using Hilhorst integral transformation which provides exact
solutions in the framework of Tsallis statistics. The results have been
reassessed with the standard results to illustrate the effect of
nonextensivity.

</DOC>
<DOC>
<DOCNO> 83116 </DOCNO>
Hypothetical revision and matter-of-fact supposition


  The paper studies the notion of supposition encoded in non-Archimedean
conditional probability (and revealed in the acceptance of the so-called
indicative conditionals). The notion of qualitative change of view that thus
arises is axiomatized and compared with standard notions like AGM and UPDATE.
Applications in the following fields are discussed: (1) theory of games and
decisions, (2) causal models, (3) non-monotonic logic.

</DOC>
<DOC>
<DOCNO> 123098 </DOCNO>
ISO spectroscopy of circumstellar dust in 14 Herbig Ae/Be systems:


  We present Infrared Space Observatory (ISO) spectra of fourteen isolated
Herbig Ae/Be (HAEBE) stars, to study the characteristics of their circumstellar
dust. These spectra show large star-to-star differences, in the emission
features of both carbon-rich and oxygen-rich dust grains. The IR spectra were
combined with photometric data ranging from the UV through the optical into the
sub-mm region. We defined two key groups, based upon the spectral shape of the
infrared region. The derived results can be summarized as follows: (1) the
continuum of the IR to sub-mm region of all stars can be reconstructed by the
sum of a power-law and a cool component, which can be represented by a black
body. Possible locations for these components are an optically thick,
geometrically thin disc (power-law component) and an optically thin flared
region (black body); (2) all stars have a substantial amount of cold dust
around them, independent of the amount of mid-IR excess they show; (3) also the
near-IR excess is unrelated to the mid-IR excess, indicating different
composition/location of the emitting material; (4) remarkably, some sources
lack the silicate bands; (5) apart from amorphous silicates, we find evidence
for crystalline silicates in several stars, some of which are new detections;
(6) PAH bands are present in at least 50% of our sample, and their appearance
is slightly different from PAHs in the ISM; (7) PAH bands are, with one
exception, not present in sources which only show a power-law continuum in the
IR; their presence is unrelated to the presence of the silicate bands; (8) the
dust in HAEBE stars shows strong evidence for coagulation; this dust processing
is unrelated to any of the central star properties (such as age, spectral type
and activity).

</DOC>
<DOC>
<DOCNO> 39830 </DOCNO>
Photon colliders: key problems, new ideas


  High energy photon colliders based on laser backscattering are a very natural
extension of a e+e- linear colliders and open new possibilities to study of the
matter. This option has been included in the pre-conceptual designs of linear
colliders and work on Technical Design Reports is in progress. The physics
motivation for photon colliders is quite clear though more studies are needed.
The proof of its technical feasibility and the search for the best solutions is
of first priority now. In this talk we discuss: physics motivation, laser
problems and new possible solutions, and generation of low emittance beams
needed for obtaining very high luminosities.

</DOC>
<DOC>
<DOCNO> 101033 </DOCNO>
Perverse Cohomology and the Vanishing Index Theorem


  The characteristic cycle of a complex of sheaves on a complex analytic space
provides weak information about the complex; essentially, it yields the Euler
characteristics of the hypercohomology of normal data to strata. We show how
perverse cohomology actually allows one to extract the individual Betti numbers
of the hypercohomology of normal data to strata, not merely the Euler
characteristics. We apply this to the ``calculation'' of the vanishing cycles
of a complex, and relate this to the work of Parusi\'nski and Brian\c{c}on,
Maisonobe, and Merle on Thom's $a_f$ condition.

</DOC>
<DOC>
<DOCNO> 100521 </DOCNO>
Explicit towers of Drinfeld modular curves


  We give explicit equations for the simplest towers of Drinfeld modular curves
over any finite field, and observe that they coincide with the asymptotically
optimal towers of curves constructed by Garcia and Stichtenoth.

</DOC>
<DOC>
<DOCNO> 119892 </DOCNO>
Simulation of Water Cerenkov Detectors Using {\sc geant4}


  We present a detailed simulation of the performance of water Cerenkov
detectors suitable for use in the Pierre Auger Observatory. Using {\sc geant4},
a flexible object-oriented simulation program, including all known physics
processes, has been developed. The program also allows interactive
visualization, and can easily be modified for any experimental setup.

</DOC>
<DOC>
<DOCNO> 118218 </DOCNO>
A Nearby Supernovae Search: Eros2


  Type Ia supernovae (SNIa) have been used as approximate standard candles to
measure cosmological parameters such as the Hubble constant and the
deceleration parameter. These measurements rely on empirical correlations
between peak luminosities and other features that can be observed in the
supernovae spectra and their light curves. Such correlations deserve further
study since they have been established from small samples of nearby SNIa. Two
years ago, the EROS2 collaboration launched an automated search for supernovae
with the 1m Marly telescope operating at La Silla. In all, 57 SNe have been
discovered in this EROS2 search and spectra have been obtained for 26 of them.
We found that 75% were of type Ia and 25% of type II. Using this sample, a
preliminary SN explosion rate has been obtained. Our most recent observation
campaign took place in February and March 99. It was performed in the framework
of a large consortium led by the {\em Supernova Cosmology Project}. The aim of
this intensive campaign was to provide an independent set of high quality light
curves and spectra to study systematic effects in the measurement of
cosmological parameters. We will briefly describe our search procedure and
present the status of our ongoing analysis.

</DOC>
<DOC>
<DOCNO> 84365 </DOCNO>
Focusing Vacuum Fluctuations


  The focusing of the vacuum modes of a quantized field by a parabolic mirror
is investigated. We use a geometric optics approximation to calculate the
energy density and mean squared field averages for scalar and electromagnetic
fields near the focus. We find that these quantities grow as an inverse power
of the distance to the focus. There is an attractive Casimir-Polder force on an
atom which will draw it into the focus. Some estimates of the magnitude of the
effects of this focusing indicate that it may be observable.

</DOC>
<DOC>
<DOCNO> 69450 </DOCNO>
Strong decays and Adler selfconsistency condition in two-dimensional QCD


  Strong mesonic decays are studied in the framework of the 't Hooft model for
the two-dimensional QCD in the axial gauge. Special attention is payed to the
processes with pions in the final state involved and the low energy theorems
have been checked including the "Adler zero". It is demonstrated explicitly
that in the chiral limit any three-meson decay amplitude with at least one pion
vertex vanishes identically for any values of the external momenta. Ward
identities for the dressed vector and axial-vector currents vertices are
identified and their relationship to the pionic vertex are discussed.

</DOC>
<DOC>
<DOCNO> 123275 </DOCNO>
Cosmic Particle Acceleration: Basic Issues


  Cosmic-rays are ubiquitous, but their origins are surprisingly difficult to
understand. A review is presented of some of the basic issues common to cosmic
particle accelerators and arguments leading to the likely importance of
diffusive shock acceleration as a general explanation. The basic theory of
diffusive shock acceleration is outlined, followed by a discussion of some of
the key issues that still prevent us from a full understanding of its outcomes.
Some recent insights are mentioned at the end that may help direct ultimate
resolution of our uncertainties.

</DOC>
<DOC>
<DOCNO> 119773 </DOCNO>
On cooling flows and the Sunyaev-Zel'dovich effect


  We study the effect of cooling flows in galaxy clusters on the
Sunyaev-Zel'dovich (SZ) distortion and the possible cosmological implications.
The SZ effect, alongwith X-ray observations of clusters, is used to determine
the Hubble constant, $H_{\circ}$. Blank sky surveys of SZ effect are being
planned to constrain the geometry of the universe through cluster counts. It is
also known that a significant fraction of clusters has cooling flows in them,
which changes the pressure profile of intracluster gas. Since the SZ decrement
depends essentially on the pressure profile, it is important to study possible
changes in the determination of cosmological parameters in the presence of a
cooling flow. We build several representative models of cooling flows and
compare the results with the corresponding case of gas in hydrostatic
equilibrium. We find that cooling flows can lead to an overestimation of the
Hubble constant. Specifically, we find that for realistic models of cooling
flow with mass deposition (varying $\dot m$ with radius), there is of the order
$\sim 10 %$ deviation in the estimated value of the Hubble constant (from that
for gas without a cooling flow) even after excluding $ \sim 80 %$ of the
cooling flow region from the analysis. We also discuss the implications of
using cluster counts from SZ observations to constrain other cosmological
parameters, in the presence of clusters with cooling flows.

</DOC>
<DOC>
<DOCNO> 68652 </DOCNO>
Neutralino pair production at proton-proton collider


  In this paper we investigated the Drell-Yan process of the light neutralino
pair $\tilde{\chi}^0_{i}\tilde{\chi}^0_{j}~(i,j=1,2)$ productions at hadron
colliders. We studied the dependence of the coupling properties of two light
neutralino $\tilde{\chi}^0_{1,2}$ on the three SUSY Lagrangian parameters
$M_1$, $M_2$ and $\mu$, and find that the production rate of $\tilde{\chi}^0_1
\tilde{\chi}^0_2$ pair will be dominated by the Higgsino-like couplings under
the condition $\mu \ll M_2$ and $\mu \sim M_1$, while the productions of
$\tilde{\chi}^0_1\tilde{\chi}^0_1$ and $\tilde{\chi}^0_2\tilde{\chi}^0_2$ pairs
will be enhanced by the gaugino-like couplings under $M_i \ll \mu$. For the
Higgsino-like $\tilde{\chi}^0_{1,2}$ neutralinos, the cross section of
$\tilde{\chi}^0_1\tilde{\chi}^0_2$ production at the LHC can reach $100~fb$.

</DOC>
<DOC>
<DOCNO> 70528 </DOCNO>
Deconfinement and the Hagedorn Transition in String Theory


  We introduce a new definition of the thermal partition function in string
theory. With this new definition, the thermal partition functions of all of the
string theories obey thermal duality relations with a Kosterlitz-Thouless phase
transition at the Hagedorn point. A \beta \to \beta_C^2/\beta transformation
maps the type I theory into a new string theory (type \tilde{I}) with thermal
Dpbranes, spatial hypersurfaces supporting a p-dimensional finite temperature
non-abelian Higgs-gauge theory for p \le 9. We demonstrate a continuous phase
transition in the behavior of the static heavy quark-antiquark potential for
small separations, (r_*)^2 << \alpha^\prime, transitioning through a precise
inverse power law at critical temperature T_D = (T_C r_*)/(2\alpha')^{1/2}\pi.

</DOC>
<DOC>
<DOCNO> 151330 </DOCNO>
Divergences in the Casimir energy


  The divergence found by Nesterenko, Lambiase and Scarpetta in the Casimir
energy on a semi-circular cylinder is attributed to the existence of edges.

</DOC>
<DOC>
<DOCNO> 100123 </DOCNO>
Mirror symmetry and C^\times


  We show that counting functions of covers of $\mathbb{C}^\times$ are equal to
sums of integrals associated to certain `Feynman' graphs. This is an analogue
of the mirror symmetry for elliptic curves by Dijkgraaf.

</DOC>
<DOC>
<DOCNO> 83083 </DOCNO>
On Automata with Boundary


  We present a theory of automata with boundary for designing, modelling and
analysing distributed systems. Notions of behaviour, design and simulation
appropriate to the theory are defined. The problem of model checking for
deadlock detection is discussed, and an algorithm for state space reduction in
exhaustive search, based on the theory presented here, is described. Three
examples of the application of the theory are given, one in the course of the
development of the ideas and two as illustrative examples of the use of the
theory.

</DOC>
<DOC>
<DOCNO> 12062 </DOCNO>
Partition asymptotics from one-dimensional quantum entropy and energy


  We give an alternative method to that of Hardy-Ramanujan-Rademacher to derive
the leading exponential term in the asymptotic approximation to the partition
function p(n,a), defined as the number of decompositions of a positive integer
'n' into integer summands, with each summand appearing at most 'a' times in a
given decomposition. The derivation involves mapping to an equivalent physical
problem concerning the quantum entropy and energy currents of particles flowing
in a one-dimensional channel connecting thermal reservoirs, and which obey
Gentile's intermediate statistics with statistical parameter 'a'. The method is
also applied to partitions associated with Haldane's fractional exclusion
statistics.

</DOC>
<DOC>
<DOCNO> 150886 </DOCNO>
Projections in string theory and boundary states for Gepner models


  In string theory various projections have to be imposed to ensure
supersymmetry. We study the consequences of these projections in the presence
of world sheet boundaries. A-type boundary conditions come in several classes;
only boundary fields that do not change the class preserve supersymmetry. Our
analysis takes in particular properly into account the resolution of fixed
points under the projections. Thus e.g. the compositeness of some previously
considered boundary states of Gepner models follows from chiral properties of
the projections. Our arguments are model independent; in particular,
integrality of all annulus coefficients is ensured by model independent
arguments.

</DOC>
<DOC>
<DOCNO> 10057 </DOCNO>
Spin-accumulation and Andreev-reflection in a mesoscopic ferromagnetic


  The electron transport though ferromagnetic metal-superconducting hybrid
devices is considered in the non-equilibrium Green's function formalism in the
quasiclassical approximation. Attention if focused on the limit in which the
exchange splitting in the ferromagnet is much larger than the superconducting
energy gap. Transport properties are then governed by an interplay between
spin-accumulation close to the interface and Andreev reflection at the
interface. We find that the resistance can either be enhanced or lowered in
comparison to the normal case and can have a non-monotonic temperature and
voltage dependence. In the non-linear voltage regime electron heating effects
may govern the transport properties, leading to qualitative different behaviour
than in the absence of heating effects. Recent experimental results on the
effect of the superconductor on the conductance of the ferromagnet can be
understood by our results for the energy-dependent interface resistance
together with effects of spin- accumulation without invoking long range pairing
correlations in the ferromagnet.

</DOC>
<DOC>
<DOCNO> 178835 </DOCNO>
Two-Body Random Ensembles: From Nuclear Spectra to Random Polynomials


  The two-body random ensemble (TBRE) for a many-body bosonic theory is mapped
to a problem of random polynomials on the unit interval. In this way one can
understand the predominance of 0+ ground states, and analytic expressions can
be derived for distributions of lowest eigenvalues, energy gaps, density of
states and so forth. Recently studied nuclear spectroscopic properties are
addressed.

</DOC>
<DOC>
<DOCNO> 84339 </DOCNO>
A classification of spherically symmetric self-similar dust models


  We classify all spherically symmetric dust solutions of Einstein's equations
which are self-similar in the sense that all dimensionless variables depend
only upon $z\equiv r/t$. We show that the equations can be reduced to a special
case of the general perfect fluid models with equation of state $p=\alpha \mu$.
The most general dust solution can be written down explicitly and is described
by two parameters. The first one (E) corresponds to the asymptotic energy at
large $|z|$, while the second one (D) specifies the value of z at the
singularity which characterizes such models. The E=D=0 solution is just the
flat Friedmann model. The 1-parameter family of solutions with z>0 and D=0 are
inhomogeneous cosmological models which expand from a Big Bang singularity at
t=0 and are asymptotically Friedmann at large z; models with E>0 are everywhere
underdense relative to Friedmann and expand forever, while those with E<0 are
everywhere overdense and recollapse to a black hole containing another
singularity. The black hole always has an apparent horizon but need not have an
event horizon. The D=0 solutions with z<0 are just the time reverse of the z>0
ones. The 2-parameter solutions with D>0 again represent inhomogeneous
cosmological models but the Big Bang singularity is at $z=-1/D$, the Big Crunch
singularity is at $z=+1/D$, and any particular solution necessarily spans both
z<0 and z>0. While there is no static model in the dust case, all these
solutions are asymptotically ``quasi-static'' at large $|z|$. As in the D=0
case, the ones with $E \ge 0$ expand or contract monotonically but the latter
may now contain a naked singularity. The ones with E<0 expand from or
recollapse to a second singularity, the latter containing a black hole.

</DOC>
<DOC>
<DOCNO> 8241 </DOCNO>
Phonon Scattering and Internal Friction in Dielectric and Metallic Films


  We have measured the heat conduction between 0.05 K and 1.0 K of high purity
silicon wafers carrying on their polished faces a variety of thin dielectric
films and polycrystalline thin metallic films. Using a Monte Carlo simulation
to analyze the conduction measurements, we have determined the phonon mean free
path within the films, and found all of them to be much shorter even than in
typical bulk amorphous solids, with no exceptions. We have also measured the
internal friction of these films below 10 K and found, however, their internal
friction at low temperatures strikingly close to that of amorphous solids, both
in magnitude and in their temperature independence, with the exception of the
MBE Si and alloy Al 5056, whose internal friction is even much smaller than
that of amorphous solids. The internal friction results indicate the phonon
scattering in these thin films is the same as, or even much less stronger than,
in other amorphous solids, according to the Tunneling Model. Thus, we conclude
that the heat conduction measurements do not support the picture that the
lattice vibrations of these films are glasslike, as had been surmised earlier
for thin metallic films, on the basis of low temperature internal friction
measurements alone [Phys. Rev. B 59, 11767 (1999)]. At the least, the films
must contain additional scattering centers which lead to the very small phonon
mean free path. Most remarkably, the MBE Si shows the same strong scattering of
thermal phonons as do the other films, while having the negligible internal
friction expected for a perfect film. The disorder causing the strong
scattering of the thermal phonons in this film is completely unknown. The
non-glasslike phonon scattering phenomena observed here in thin dielectric and
metallic films deserve further investigations.

</DOC>
<DOC>
<DOCNO> 83262 </DOCNO>
Performing work efficiently in the presence of faults


  We consider a system of t synchronous processes that communicate only by
sending messages to one another, and that together must perform $n$ independent
units of work. Processes may fail by crashing; we want to guarantee that in
every execution of the protocol in which at least one process survives, all n
units of work will be performed. We consider three parameters: the number of
messages sent, the total number of units of work performed (including
multiplicities), and time. We present three protocols for solving the problem.
All three are work-optimal, doing O(n+t) work. The first has moderate costs in
the remaining two parameters, sending O(t\sqrt{t}) messages, and taking O(n+t)
time. This protocol can be easily modified to run in any completely
asynchronous system equipped with a failure detection mechanism. The second
sends only O(t log{t}) messages, but its running time is large (exponential in
n and t). The third is essentially time-optimal in the (usual) case in which
there are no failures, and its time complexity degrades gracefully as the
number of failures increases.

</DOC>
<DOC>
<DOCNO> 71621 </DOCNO>
A search for Z' in muon neutrino associated charm production


  In many extensions of the Standard Model the presence of an extra neutral
boson, Z', is invoked. A precision study of weak neutral-current exchange
processes involving only second generation fermions is still missing. We
propose a search for Z' in muon neutrino associated charm production. This
process only involves Z' couplings with fermions from the second generation. An
experimental method is thoroughly described using an ideal detector. As an
application, the accuracy reachable with present and future experiments has
been estimated.

</DOC>
<DOC>
<DOCNO> 71757 </DOCNO>
B-> J/\psi K Decays in QCD Factorization


  The hadronic decays $B\to J/\psi K(K^*)$ are interesting because
experimentally they are the only color-suppressed modes which have been
measured, and theoretically they are calculable by QCD factorization even the
emitted meson $J\psi$ is heavy. We analyze the decay $B\to J\psi K$ within the
framework of QCD factorization in the heavy quark limit. We show explicitly the
scale and $\gamma_5$-scheme independence of decay amplitudes and infrared
safety of nonfactorizable corrections at twist-2 order. Leading-twist
contributions from the light-cone distribution amplitudes (LCDAs) of the mesons
are too small to accommodate the data; the nonfactorizable corrections to naive
factorization are small and not significant. We study the twist-3 effects due
to the kaon and find that the coefficient $a_2(J\psi K)$ is largely enhanced by
the nonfactorizable spectator interactions arising from the twist-3 kaon LCDA
$\phi^K_\sigma$, which are formally power-suppressed but chirally,
logarithmically and kinematically enhanced. Therefore, factorization breaks
down at twist-3 order. Higher-twist effects of $J\psi$ are briefly discussed.
Our result also resolves the long-standing sign ambiguity of $a_2(J\psi K)$,
which turns out to be positive for its real part.

</DOC>
<DOC>
<DOCNO> 116603 </DOCNO>
Geometry of River Networks III: Characterization of Component


  River networks serve as a paradigmatic example of all branching networks.
Essential to understanding the overall structure of river networks is a
knowledge of their detailed architecture. Here we show that sub-branches are
distributed exponentially in size and that they are randomly distributed in
space, thereby completely characterizing the most basic level of river network
description. Specifically, an averaged view of network architecture is first
provided by a proposed self-similarity statement about the scaling of drainage
density, a local measure of stream concentration. This scaling of drainage
density is shown to imply Tokunaga's law, a description of the scaling of side
branch abundance along a given stream, as well as a scaling law for stream
lengths. This establishes the scaling of the length scale associated with
drainage density as the basic signature of self-similarity in river networks.
We then consider fluctuations in drainage density and consequently the numbers
of side branches. Data is analyzed for the Mississippi River basin and a model
of random directed networks. Numbers of side streams are found to follow
exponential distributions as are stream lengths and inter-tributary distances
along streams. Finally, we derive the joint variation of side stream abundance
with stream length, affording a full description of fluctuations in network
structure. Fluctuations in side stream numbers are shown to be a direct result
of fluctuations in stream lengths. This is the last paper in a series of three
on the geometry of river networks.

</DOC>
<DOC>
<DOCNO> 100353 </DOCNO>
State Extended Uncertainty Relations


  A scheme for construction of uncertainty relations (UR) for n observables and
m states is presented. Several lowest order UR are displayed and briefly
discussed. For two states |\psi> and |\phi> and canonical observables the
(entangled) extension of Heisenberg UR reads [\Delta p(\psi)]^2[\Delta
q(\phi)]^2 + [\Delta p(\phi)]^2[\Delta q(\psi)]^2 \geq 1/2. Some possible
applications of the new inequalities are noted.

</DOC>
<DOC>
<DOCNO> 151223 </DOCNO>
Chan-Paton Soliton Gauge States of Compatified Open String


  We study the mechanism of enhanced gauge symmetry of bosonic open string
compatified on torus by analyzing the zero-norm soliton (nonzero winding of
wilson line) gauge states in the spectrum. Unlike the closed string case, we
find that the soliton gauge state exists only at massive levels. These soliton
gauge states correspond to the existence of enhanced massive gauge symmetries
with transformation parameters containing both Einstein and Yang-Mills indices.
In the T-dual picture, these symmetries exist only at some discrete values of
compatified radii when N D-branes are coincident.

</DOC>
<DOC>
<DOCNO> 99287 </DOCNO>
Braid group actions on derived categories of coherent sheaves


  This paper gives a construction of braid group actions on the derived
category of coherent sheaves on a variety $X$. The motivation for this is
Kontsevich's homological mirror conjecture, together with the occurrence of
certain braid group actions in symplectic geometry. One of the main results is
that when $\dim X \geq 2$, our braid group actions are always faithful.
  We describe conjectural mirror symmetries between smoothings and resolutions
of singularities that lead us to find examples of braid group actions arising
from crepant resolutions of various singularities. Relations with the McKay
correspondence and with exceptional sheaves on Fano manifolds are given.
Moreover, the case of an elliptic curve is worked out in some detail.

</DOC>
<DOC>
<DOCNO> 170504 </DOCNO>
Laser Cooling of Trapped Fermi Gases deeply below the Fermi Temperature


  We study the collective Raman cooling of a polarized trapped Fermi gas in the
Festina Lente regime, when the heating effects associated with photon
reabsorptions are suppressed. We demonstrate that by adjusting the spontaneous
Raman emission rates one can achieve temperatures of the order of 10% of the
Fermi temperature, $T_F$. Furthermore, we show that, using appropriately
designed anharmonic traps, temperatures of $0.01 T_F$ can be reached.

</DOC>
<DOC>
<DOCNO> 101451 </DOCNO>
Half twists and the cohomology of hypersurfaces


  A Hodge structure V of weight k on which a CM field acts defines, under
certain conditions, a Hodge structure of weight k-1, its half twist. In this
paper we consider hypersurfaces in projective space with a cyclic automorphism
which defines an action of a cyclotomic field on a Hodge substructure in the
cohomology. We determine when the half twist exists and relate it to the
geometry and moduli of the hypersurfaces. We use our results to prove the
existence of a Kuga-Satake correspondance for certain cubic 4-folds.

</DOC>
<DOC>
<DOCNO> 121345 </DOCNO>
The Mass Distribution in Low Surface Brightness Galaxies


  The distribution of the stellar and gaseous components in low surface
brightness galaxies has been determined directly from optical and HI imaging.
The distribution of what might be the dominant mass component, the dark matter,
which is inferred from rotation curves, is far harder to determine. Although
the rotation curves themselves can be determined fairly accurately from HI
synthesis observations, and in particular from H$\alpha$ spectroscopy, the
uncertainty in the mass modeling leaves room for a wide range of possible dark
matter distributions, ranging from maximum stellar disks with shallow dark
halos to cuspy dark halos with little mass in stars.

</DOC>
<DOC>
<DOCNO> 151031 </DOCNO>
Remarks on Dirac-like Monopole, Maxwell and Maxwell-Chern-Simons


  Classical Maxwell and Maxwell-Chern-Simons (MCS) Electrodynamics in (2+1)D
are studied in some details. General expressions for the potential and fields
are obtained for both models, and some particular cases are explicitly solved.
Conceptual and technical difficulties arise, however, for accelerated charges.
The propagation of electromagnetic signals is also studied and their
reverberation is worked out and discussed. Furthermore, we show that a
Dirac-like monopole yields a (static) tangential electric field. We also
discuss some classical and quantum consequences of the field created by such a
monopole when acting upon an usual electric charge. In particular, we show that
at large distances, the dynamics of one single charged particle under the
action of such a potential and a constant (external) magnetic field as well,
reduces to that of one central harmonic oscillator, presenting, however, an
interesting angular sector which admits energy-eigenvalues. Among other
peculiarities, both sectors, the radial and the angular one, present
non-vanishing energy-eigenvalues for their lowest level. Moreover, those
associated to the angle are shown to respond to discrete shifts of such a
variable. We also raise the question whether the formation of bound states is
possible in the system.

</DOC>
<DOC>
<DOCNO> 67999 </DOCNO>
Non-saturation of the J/psi suppression at large transverse energy in


  We show that, contrary to recent claims, the $J/\psi$ suppression resulting
from its interaction with comovers does not saturate at large transverse energy
$E_T$. On the contrary, it shows a characteristic structure - change of
curvature near the knee of the $E_T$ distribution - which is due to the $E_T$
(or multiplicity) fluctuation, and agrees with recent experimental results.

</DOC>
<DOC>
<DOCNO> 100695 </DOCNO>
Euler number of Instanton Moduli space and Seiberg-Witten invariants


  We show that a partition function of topological twisted N=4 Yang-Mills
theory is given by Seiberg-Witten invariants on a Riemannian four manifolds
under the condition that the sum of Euler number and signature of the four
manifolds vanish. The partition function is the sum of Euler number of
instanton moduli space when it is possible to apply the vanishing theorem. And
we get a relation of Euler number labeled by the instanton number $k$ with
Seiberg-Witten invariants, too. All calculation in this paper is done without
assuming duality.

</DOC>
<DOC>
<DOCNO> 68546 </DOCNO>
Brane New World


  We study a Randall-Sundrum cosmological scenario consisting of a domain wall
in anti-de Sitter space with a strongly coupled large $N$ conformal field
theory living on the wall. The AdS/CFT correspondence allows a fully quantum
mechanical treatment of this CFT, in contrast with the usual treatment of
matter fields in inflationary cosmology. The conformal anomaly of the CFT
provides an effective tension which leads to a de Sitter geometry for the
domain wall. This is the analogue of Starobinsky's four dimensional model of
anomaly driven inflation. Studying this model in a Euclidean setting gives a
natural choice of boundary conditions at the horizon. We calculate the graviton
correlator using the Hartle-Hawking ``No Boundary'' proposal and analytically
continue to Lorentzian signature. We find that the CFT strongly suppresses
metric perturbations on all but the largest angular scales. This is true
independently of how the de Sitter geometry arises, i.e., it is also true for
four dimensional Einstein gravity. Since generic matter would be expected to
behave like a CFT on small scales, our results suggest that tensor
perturbations on small scales are far smaller than predicted by all previous
calculations, which have neglected the effects of matter on tensor
perturbations.

</DOC>
<DOC>
<DOCNO> 9472 </DOCNO>
Lattice dynamical effects on the Peierls transition in one-dimensional


  The interplay of charge, spin and lattice degrees of freedom is studied for
quasi-one-dimensional electron and spin systems coupled to quantum phonons.
Special emphasis is put on the influence of the lattice dynamics on the Peierls
transition. Using exact diagonalization techniques the ground-state and
spectral properties of the Holstein model of spinless fermions and of a
frustrated Heisenberg model with magneto-elastic coupling are analyzed on
finite chains. In the non-adiabatic regime a (T=0) quantum phase transition
from a gapless Luttinger-liquid/spin-fluid state to a gapped dimerized phase
occurs at a nonzero critical value of the electron/spin-phonon interaction. To
study the nature of the spin-Peierls transition at finite temperatures for the
infinite system, an alternative Green's function approach is applied to the
magnetostrictive XY model. With increasing phonon frequency the structure
factor shows a remarkable crossover from soft-mode to central-peak behaviour.
The results are discussed in relation to recent experiments on $\rm CuGeO_3$.

</DOC>
<DOC>
<DOCNO> 85249 </DOCNO>
A Tolman-Bondi-Lemaitre Cell-Model for the Universe and Gravitational


  A piecewise Tolman-Bondi-Lemaitre (TBL) cell-model for the universe
incorporating local collapsing and expanding inhomogeneities is presented here.
The cell-model is made up of TBL underdense and overdense spherical regions
surrounded by an intermediate region of TBL shells embedded in an expanding
universe. The cell-model generalizes the Friedmann as well as Einstein-Straus
swiss-cheese models and presents a number of advantages over other models, and
in particular the time evolution of the cosmological inhomogeneities is now
incorporated within the scheme. Important problem of gravitational collapse of
a massive dust cloud, such as a cluster of galaxies or even a massive star, in
such a cosmological background is examined. It is shown that the collapsing
local inhomogeneities in an expanding universe could result in either a black
hole, or a naked singularity, depending on the nature of the set of initial
data which consists of the matter distribution and the velocities of the
collapsing shells in the cloud at the initial epoch from which the collapse
commences.

</DOC>
<DOC>
<DOCNO> 85473 </DOCNO>
Numerical Study of Length Spectra and Low-lying Eigenvalue Spectra of


  In this paper, we numerically investigate the length spectra and the
low-lying eigenvalue spectra of the Laplace-Beltrami operator for a large
number of small compact(closed) hyperbolic (CH) 3-manifolds. The first non-zero
eigenvalues have been successfully computed using the periodic orbit sum
method, which are compared with various geometric quantities such as volume,
diameter and length of the shortest periodic geodesic of the manifolds. The
deviation of low-lying eigenvalue spectra of manifolds converging to a cusped
hyperbolic manifold from the asymptotic distribution has been measured by
$\zeta-$ function and spectral distance.

</DOC>
<DOC>
<DOCNO> 151430 </DOCNO>
Scattering in Three Dimensional Extremal Black Holes


  An approach to scattering theory in three dimensional AdS spaces is proposed.
Firstly we consider the scattering of spinless relativistic particles by a
three dimensional extremal black hole and compute the absorption cross section
$\sigma_{abs} =J_{abs}/J_{\infty}$ without using {\it in} and {\it out} states.
Secondly, we posit a reciprocal space ${\cal H}$ where {\it in} and {\it out}
states and the scattering amplitude is defined as in usual scattering theory.
We show that both descriptions are equivalent and ${\cal H}$ could be
considered as the space where the scattering processes in AdS should be
defined.

</DOC>
<DOC>
<DOCNO> 121650 </DOCNO>
Topology and Polarisation of Subbeams Associated With Pulsar 0943+10's


  The ``drifting'' subpulses exhibited by some radio pulsars have fascinated
both observers and theorists for 30 years, and have been widely regarded as one
of the most critical and potentially insightful aspects of their emission.
Here, we report on detailed studies of pulsar B0943+10, whose nearly coherent
sequences of ``drifting'' subpulses have permitted us to identify their origin
as a system of subbeams that appear to circulate around the star's magnetic
axis. We introduce several new techniques of analysis, and we find that both
the primary and secondary features in the star's fluctuation spectra are
aliases of their actual values. We have also developed a method of tracing the
underlying pattern responsible for the observed sequences, using a
``cartographic'' transform and its inverse, permitting us to study the
characteristics of the polar-cap emission ``map'' and to confirm that such a
``map'' in turn represents the observed sequence. We apply these techniques to
the study of three different Arecibo observations. The ``B''-mode sequences are
consistent in revealing that the emission pattern consists of 20 subbeams,
which rotate around the magnetic axis in about 37 periods or 41 seconds. Even
in the ``Q'' mode sequence, we find evidence of a compatible circulation time.
The similarity of the subbeam patterns at different radio frequencies strongly
suggests that the radiation is produced within a set of columns, which extend
from close to the stellar surface up though the emission region and reflect
some manner of a ``seeding''phenomenon at their base. The subbeam emission is
then tied neither to the stellar surface nor to the field.

</DOC>
<DOC>
<DOCNO> 121616 </DOCNO>
Sub-mm counterparts to Lyman-break galaxies


  We summarize the main results from our SCUBA survey of Lyman-break galaxies
(LBGs) at z~3. Analysis of our sample of LBGs reveals a mean flux of
S850=0.6$\pm$0.2 mJy, while simple models of emission based on the UV
properties predict a mean flux about twice as large. Known populations of LBGs
are expected to contribute flux to the weak sub-mm source portion of the far-IR
background, but are not likely to comprise the bright source (S850>5 mJy) end
of the SCUBA-detected source count. The detection of the LBG, Westphal-MM8, at
1.9 mJy suggests that deeper observations of individual LBGs in our sample
could uncover detections at similar levels, consistent with our UV-based
predictions. By the same token, many sub-mm selected sources with S850<2 mJy
could be LBGs. The data are also consistent with the FarIR/$\beta$ relation
holding at z=3.

</DOC>
<DOC>
<DOCNO> 120305 </DOCNO>
Monsters at the Heart of Galaxy Formation


  Surveys with the Hubble Space Telescope find supermassive black holes (BHs)
of 10**6 to 10**9.5 solar masses in every galaxy that has an
elliptical-galaxy-like "bulge" component. BHs appear to be standard equipment
in galaxy bulges. At the 2000 June meeting of the American Astronomical
Society, two groups announced the discovery of a tight correlation between BH
mass and the global velocity dispersion of stars in the host galaxy bulge
(astro-ph/0006053 and astro-ph/0006289). Also, BH mass scales with bulge mass;
the median BH mass fraction is 0.15 % of the bulge mass. In contrast, BH mass
does not scale with disk properties. Pure disk galaxies - ones that lack a
bulge component - must have BH mass fractions that are much smaller than the BH
mass fractions in bulges. These results imply a close connection between BH
growth and bulge (but not disk) formation. Observations increasingly support
the hypothesis that the major events that form a bulge or elliptical galaxy and
the main growth phases of its BH - when it shone like a quasar - were the same
events. These and other results are leading to a profound change in how
astronomers view BHs. More than just exotica needed to explain rare active
galactic nuclei, they are becoming an integral part of our understanding of
galaxy formation.

</DOC>
<DOC>
<DOCNO> 117162 </DOCNO>
The Heats of Dilution. Calorimetry and Van't-Hoff


  Earlier it has been found that there is a big difference between heats of
dilution measured by calorimetry and by the Van't-Hoff equation. In the present
paper a reason for that is proposed. Experimental data for dilution of benzene
and n-hexane in water were used.

</DOC>
<DOC>
<DOCNO> 151557 </DOCNO>
Yang-Baxter Equation on Two-Dimensional Lattice and Some Infinite


  We show that the Yang-Baxter equation is equivalent to the associativity of
the algebra generated by non-commuting link operators. Starting from these link
operators we build out the (FFZ) algebras, the $s\ell_q (2)$ is derived by
considering a special combination of the generators of (FFZ) algebra.

</DOC>
<DOC>
<DOCNO> 121481 </DOCNO>
Broad-band diffuse gamma ray emission of the Galactic Disk


  The contributions of different radiation mechanisms to the diffuse gamma-ray
emission of the galactic disk are studied in a broad energy region from X-rays
to very high energy gamma rays.

</DOC>
<DOC>
<DOCNO> 101797 </DOCNO>
Vertex algebras and the cohomology ring structure of Hilbert schemes of


  Using vertex algebra techniques, we determine a set of generators for the
cohomology ring of the Hilbert schemes of points on an arbitrary smooth
projective surface over the field of complex numbers.

</DOC>
<DOC>
<DOCNO> 120912 </DOCNO>
Evolution of Stellar Collision Products in Globular Clusters - II.


  We continue our exploration of collisionally merged stars in the blue
straggler region of the color-magnitude diagram. We report the results of new
SPH calculations of parabolic collisions between two main-sequence stars, with
the initial structure and composition profiles of the parent stars having been
determined from stellar evolution calculations. Parallelization of the SPH code
has permitted much higher numerical resolution of the hydrodynamics. We also
present evolutionary tracks for the resulting collision products, which emerge
as rapidly rotating blue stragglers. The rotating collision products are
brighter, bluer and remain on the main sequence longer than their non-rotating
counterparts. In addition, they retain their rapid rotation rates throughout
their main sequence lifetime. Rotationally-induced mixing strongly affects the
evolution of the collision products, although it is not sufficient to mix the
entire star. We discuss the implications of these results for studies of blue
straggler populations in clusters. This work shows that off-axis collision
products cannot become blue stragglers unless they lose a large fraction of
their initial angular momentum. The mechanism for this loss is not apparent,
although some possibilities are discussed.

</DOC>
<DOC>
<DOCNO> 8212 </DOCNO>
How to mode-lock an atom laser


  We consider a possible technique for mode-locking an atom laser, based on the
generation of a dark soliton in a ring-shaped Bose-Einstein condensate, with
repulsive atomic interactions. The soliton is a kink, with angular momentum per
particle equal to \hbar/2. It emerges naturally, when the condensate is stirred
at the soliton velocity, and subsequently outcoupled with a periodic Raman
pulse-train. The result is a replicating coherent field inside the atom laser.
We give a numerical demonstration of the generation and stabilization of the
soliton.

</DOC>
<DOC>
<DOCNO> 71206 </DOCNO>
Exclusive and Inclusive Semileptonic Lambda_b-Decays


  In this talk we present theoretical evidence that the exclusive/inclusive
ratio of semileptonic Lambda_b-decays exceeds that of semileptonic B-decays,
where the experimental exclusive/inclusive ratio amounts to about 66%. We start
from the observation that the spectator quark model provides a lower bound on
the leading order Isgur-Wise function of the Lambda_b -> Lambda_c transition in
terms of the corresponding B -> D,D^* mesonic Isgur-Wise function. Using
experimental data for the B -> D,D^* mesonic Isgur-Wise functions this bound is
established. Applying a QCD sum rule estimate of the Lambda_b -> Lambda_c
transition form factor which satisfy the spectator quark model bound we predict
the exclusive/inclusive ratio of semileptonic Lambda_b decay rates to lie in a
range between 0.81 and 0.89. We also provide an upper bound on the baryonic
Isgur-Wise function which is determined from the requirement that the exclusive
rate should not exceed the inclusive rate. Our pre-Osaka results are discussed
in the light of new recent preliminary experimental results on the pertinent
mesonic and baryonic form factors presented at the Osaka ICHEP 2000 Conference.

</DOC>
<DOC>
<DOCNO> 100554 </DOCNO>
On t-structures and Torsion Theories Induced by Compact Objects


  First, we show that a compact object $C$ in a triangulated category, which
satisfies suitable conditions, induces a $t$-structure. Second, in an abelian
category we show that a complex $P^{\centerdot}$ of small projective objects of
term length two, which satisfies suitable conditions, induces a torsion theory.
In the case of module categories, using a torsion theory, we give equivalent
conditions for $P^{\centerdot}$ to be a tilting complex. Finally, in the case
of artin algebras, we give one to one correspondence between tilting complexes
of term length two and torsion theories with certain conditions.

</DOC>
<DOC>
<DOCNO> 10500 </DOCNO>
Decay of one dimensional surface modulations


  The relaxation process of one dimensional surface modulations is re-examined.
Surface evolution is described in terms of a standard step flow model.
Numerical evidence that the surface slope, D(x,t), obeys the scaling ansatz
D(x,t)=alpha(t)F(x) is provided. We use the scaling ansatz to transform the
discrete step model into a continuum model for surface dynamics. The model
consists of differential equations for the functions alpha(t) and F(x). The
solutions of these equations agree with simulation results of the discrete step
model. We identify two types of possible scaling solutions. Solutions of the
first type have facets at the extremum points, while in solutions of the second
type the facets are replaced by cusps. Interactions between steps of opposite
signs determine whether a system is of the first or second type. Finally, we
relate our model to an actual experiment and find good agreement between a
measured AFM snapshot and a solution of our continuum model.

</DOC>
<DOC>
<DOCNO> 120530 </DOCNO>
The Outflow-Disc Interaction in Young Stellar Objects


  In this work the most spectacular phenomena occurring during the formation of
a star are briefly reviewed: accretion through a rotating disc of matter and
outflow through the poles of the new stellar object. Magnetic fields have been
proposed to be principally responsible for the coexistence of these opposed
mechanisms of accretion and outflowing. According to different models, the
magnetic fields are either twisted or stretched by the accretion disc, allowing
the formation of polar channels through which part of the accreting matter can
escape. The high degree of coupling between the physical parameters describing
the young stellar object (e.g. circular velocity of the disc and the central
object, viscosity, strength and freezing of magnetic fields, etc.) makes
detailed understanding of the interaction between accretion discs and outflows
very difficult. The models presented here provide only a partial answer to this
difficult problem.

</DOC>
<DOC>
<DOCNO> 84396 </DOCNO>
Cosmic crystallography: the euclidean isometries


  Exact expressions for probability densities of conjugate pair separation in
euclidean isometries are obtained, for the cosmic crystallography.These are the
theoretical counterparts of the mean histograms arising from computer
simulation of the isometries. For completeness, also the isometries with fixed
points are examined, as well as the orientation reversing isometries.

</DOC>
<DOC>
<DOCNO> 70643 </DOCNO>
Neutrino Yukawa couplings and FCNC processes in B decays in SUSY-GUT


  Flavor changing neutral current and lepton flavor violating processes are
studied in the SU(5) SUSY-GUT with right-handed neutrino supermultiplets. Using
input parameters motivated by neutrino oscillation, it is shown that the
time-dependent CP asymmetry of $b \to s \gamma$ can be as large as 20%. We also
show that the $B_s$-$\bar{B}_s$ mixing can be significantly different from the
standard model prediction.

</DOC>
<DOC>
<DOCNO> 122048 </DOCNO>
A Search for Jovian Planets around Hot White Dwarfs


  Current searches for extrasolar planets have concentrated on observing the
reflex Doppler shift of solar-type stars. Little is known, however, about
planetary systems around non-solar-type stars. We suggest a new method to
extend planetary searches to hot white dwarfs. Near a hot white dwarf, the
atmosphere of a Jovian planet will be photoionized and emit hydrogen
recombination lines, which may be detected by high- dispersion spectroscopic
observations. Multi-epoch monitoring can be used to distinguish between non-LTE
stellar emission and planetary emission, and to establish the orbital
parameters of the detected planets. In the future, high-precision astrometric
measurements of the hot white dwarf will allow the masses of the detected
planets to be determined. Searches for Jovian planets around hot white dwarfs
will provide invaluable new insight on the development of planetary systems
around stars more massive than the Sun and on how stellar evolution affects
these systems. We present high-dispersion spectroscopic observations of the
white dwarf Feige 34 to demonstrate the complexity and feasibility of the
search method.

</DOC>
<DOC>
<DOCNO> 117891 </DOCNO>
High Resolution Spectroscopy of the X-ray Photoionized Wind in Cygnus


  We present a preliminary analysis of the 1--10 keV spectrum of the massive
X-ray binary Cyg X-3, obtained with the High Energy Transmission Grating
Spectrometer on the Chandra X-ray Observatory. The source reveals a richly
detailed discrete emission spectrum, with clear signatures of
photoionization-driven excitation.
  Among the spectroscopic novelties in the data are the first astrophysical
detections of a number of He-like 'triplets' (Si, S, Ar) with emission line
ratios characteristic of photoionization equilibrium, fully resolved narrow
radiative recombination continua of Mg, Si, and S, the presence of the H-like
Fe Balmer series, and a clear detection of a ~ 800 km/s large scale velocity
field, as well as a ~1500 km/s FWHM Doppler broadening in the source. We
briefly touch on the implications of these findings for the structure of the
Wolf-Rayet wind.

</DOC>
<DOC>
<DOCNO> 14138 </DOCNO>
Density of States below the Thouless Gap in a Mesoscopic SNS Junction


  Quasiclassical theory predicts an existence of a sharp energy gap E_g \sim
D/L^2 in the excitation spectrum of a long diffusive superconductor--normal
metal--superconductor (SNS) junction. We show that mesoscopic fluctuations
remove the sharp edge of the spectrum, leading to a nonzero DoS for all
energies. Physically, this effect originates from the quasi-localized states in
the normal metal. Technically, we use an extension of Efetov's supermatrix
sigma-model for mixed NS systems. We demonstrate the equivalence of the
supersymmetric saddle-point solution to the standard quasiclassical Usadel
solution, and show that the instanton solution with broken supersymmetry
provides a non-zero DoS at energies E < E_g.

</DOC>
<DOC>
<DOCNO> 122769 </DOCNO>
Efficiency of Medium-Band Surveys


  We simulate multi-color surveys, which use the same telescope time on
different filter sets of broad-band and medium-band filters. We use a
photometric classification method for identifying stars, galaxies and quasars
and for estimating multi-color redshifts of extragalactic objects. A library of
>65000 color templates is used for comparison with observed objects.
Spectroscopy from the CADIS survey has proven the performance of the method. We
learned, that medium-band surveys perform superior to broad-band surveys in
terms of classification and redshift estimation although they collect less
photons. A full account of this work is already in print.

</DOC>
<DOC>
<DOCNO> 69404 </DOCNO>
Saltatory Relaxation of the Cosmological Constant


  We modify and extend an earlier proposal by Brown and Teitelboim to relax the
effective cosmological term by nucleation of branes coupled to a three-index
gauge potential. Microscopic considerations from string/M theory suggest two
major innovations in the framework. First, the dependence of brane properties
on the compactification of extra dimensions may generate a very small quantized
unit for jumps in the effective cosmological term. Second, internal degrees of
freedom for multiply coincident branes may enhance tunneling rates by
exponentially large density of states factors. These new features essentially
alter the relaxation dynamics. By requiring stability on the scale of the
lifetime of the universe, rather than absolute stability, we derive a
non-trivial relation between the supersymmetry breaking scale and the value of
the cosmological term. It is plausibly, though not certainly, satisfied in
Nature.

</DOC>
<DOC>
<DOCNO> 102826 </DOCNO>
Discrete bispectral Darboux transformations from Jacobi operators


  We construct families of bispectral difference operators of the form a(n)T +
b(n) + c(n) T^{-1} where T is the shift operator. They are obtained as discrete
Darboux transformations from appropriate extensions of Jacobi operators. We
conjecture that along with operators previously constructed by Grunbaum, Haine,
Horozov, and Iliev they exhaust all bispectral regular (i.e. a(n)c(n) \neq 0,
for all integer n) operators of the form above.

</DOC>
<DOC>
<DOCNO> 152354 </DOCNO>
A note on Weyl transformations in two-dimensional dilaton gravity


  We discuss Weyl (conformal) transformations in two-dimensional matterless
dilaton gravity. We argue that both classical and quantum dilaton gravity
theories are invariant under Weyl transformations.

</DOC>
<DOC>
<DOCNO> 13299 </DOCNO>
High Frequency Conductivity in the Quantum Hall Regime


  We have measured the complex conductivity $\sigma_{xx}$ of a two-dimensional
electron system in the quantum Hall regime up to frequencies of 6 GHz at
electron temperatures below 100 mK. Using both its imaginary and real part we
show that $\sigma_{xx}$ can be scaled to a single function for different
frequencies and for all investigated transitions between plateaus in the
quantum Hall effect. Additionally, the conductivity in the variable-range
hopping regime is used for a direct evaluation of the localization length
$\xi$. Even for large filing factor distances $\delta \nu$ from the critical
point we find $\xi \propto \delta \nu^{-\gamma}$ with a scaling exponent
$\gamma=2.3$.

</DOC>
<DOC>
<DOCNO> 101270 </DOCNO>
Theta constants associated with the cyclic triple coverings of the


  Let $\psi$ be the period map for a family of the cyclic triple coverings of
the complex projective line branching at six points. The symmetric group $S_6$
acts on this family and on its image under $\psi.$ In this paper, we give an
$S_6$-equivariant expression of $\psi^{-1}$ in terms of fifteen theta
constants.

</DOC>
<DOC>
<DOCNO> 119578 </DOCNO>
Spectroscopy of Giant Stars in the Pyxis Globular Cluster


  The Pyxis globular cluster is a recently discovered globular cluster that
lies in the outer halo (R_{gc} ~ 40 kpc) of the Milky Way. Pyxis lies along one
of the proposed orbital planes of the Large Magellanic Cloud (LMC), and it has
been proposed to be a detached LMC globular cluster captured by the Milky Way.
We present the first measurement of the radial velocity of the Pyxis globular
cluster based on spectra of six Pyxis giant stars. The mean heliocentric radial
velocity is ~ 36 km/sec, and the corresponding velocity of Pyxis with respect
to a stationary observer at the position of the Sun is ~ -191 km/sec. This
radial velocity is a large enough fraction of the cluster's expected total
space velocity, assuming that it is bound to the Milky Way, that it allows
strict limits to be placed on the range of permissible transverse velocities
that Pyxis could have in the case that it still shares or nearly shares an
orbital pole with the LMC. We can rule out that Pyxis is on a near circular
orbit if it is Magellanic debris, but we cannot rule out an eccentric orbit
associated with the LMC. We have calculated the range of allowed proper motions
for the Pyxis globular cluster that result in the cluster having an orbital
pole within 15 degrees of the present orbital pole of the LMC and that are
consistent with our measured radial velocity, but verification of the tidal
capture hypothesis must await proper motion measurement from the Space
Interferometry Mission or HST. A spectroscopic metallicity estimate of [Fe/H] =
-1.4 +/- 0.1 is determined for Pyxis from several spectra of its brightest
giant; this is consistent with photometric determinations of the cluster
metallicity from isochrone fitting.

</DOC>
<DOC>
<DOCNO> 13123 </DOCNO>
Aggregation number distributions and mesoglobules in dilute solutions of


  We investigate the aggregation number and size distributions for
inter-molecular clusters of amphiphilic diblock and triblock copolymers in poor
solvent at very low concentrations. Diblocks and triblocks with hydrophilic
ends are shown to possess narrow distributions corresponding to formation of
monodispersed mesoglobules. Diblocks with hydrophobic ends are found to produce
inter-cluster multimers due to bridging by the hydrophilic middle blocks,
resulting in polydisperse distributions. Implications of these observations for
preparation of monodispersed nanoparticles and, potentially, understanding of
the quaternary structure of proteins are discussed.

</DOC>
<DOC>
<DOCNO> 118747 </DOCNO>
Mass Segregation in Star Clusters


  Star clusters - open and globulars - experience dynamical evolution on time
scales shorter than their age. Consequently, open and globular clusters provide
us with unique dynamical laboratories for learning about two-body relaxation,
mass segregation from equipartition of energy, and core collapse. We review
briefly, in the framework of star clusters, some elements related to the
theoretical expectation of mass segregation, the results from N-body and other
computer simulations, as well as the now substantial clear observational
evidence.

</DOC>
<DOC>
<DOCNO> 99327 </DOCNO>
Quantization of Poisson algebras associated to Lie algebroids


  We prove the existence of a strict deformation quantization for the canonical
Poisson structure on the dual of an integrable Lie algebroid. It follows that
any Lie groupoid C*-algebra may be regarded as a result of a quantization
procedure. The C*-algebra of the tangent groupoid of a given Lie groupoid G
(with Lie algebra g) is the C*-algebra of a continuous field of C*-algebras
over R with fibers A_0=C*(g)=C_0(g*) and A_h=C*(G) for nonzero h. The same is
true for the corresponding reduced C*-algebras. Our results have applications
to, e.g., transformation group C*-algebras, K-theory, and index theory.

</DOC>
<DOC>
<DOCNO> 152156 </DOCNO>
Some Computations of Partition Functions and Tachyon Potentials in


  We discuss what information can be safely extracted from background
independent off-shell string theory. The major obstacle in doing so is that
renormalization conditions of the underlying world-sheet theories are not
exactly known. To get some insight, we first consider the tachyon and gauge
field backgrounds and carry out computations in different renormalization
schemes for both, bosonic string and superstring. Next, we use a principle of
universality (renormalization scheme independence) to somehow compensate the
missing of the renormalization conditions and get information we are looking
for. It turns out that some asymptotics which are responsible for the
potentials only obey the principle of universality.

</DOC>
<DOC>
<DOCNO> 119745 </DOCNO>
X-rays and regions of star formation: a combined ROSAT-HRI/near-to-mid


  We have obtained two deep exposures of the rho Oph cloud core region with the
ROSAT HRI. The improved position accuracy (1"-6") with respect to previous
recent X-ray observations (ROSAT PSPC, and ASCA) allows us to remove positional
ambiguities for the detected sources. We also cross-correlate the X-ray
positions with IR sources found in the ISO-ISOCAM survey of the same region at
6.7 and 14.3 \mum, in addition to sources known from ground-based observations,
which are young stars. We find that there is no statistically significant
difference between the X-ray luminosity functions of HRI-detected Class II and
Class III sources, i.e., T Tauri stars with and without disks, confirming that
the contribution of these disks to X-ray emission or absorption, must be small.
Most of the sources are variable, and their variability is consistent with a
solar-like (hence magnetic) flare origin. We use the information given both by
the ISOCAM survey and by our HRI deep exposure to study the T Tauri star
population of the rho Oph dense cores. We confirm that essentially all Class II
and Class III sources are X-ray emitters, and that a strong correlation exists
between their X-ray luminosity, L_X, and their stellar luminosity, L_*, with
L_X/L_* ~ 1E-4. Most of the new ISOCAM Class II sources are not detected,
however, which we explain by the fact that their X-ray luminosities
``predicted'' on the basis of this correlation are too faint to be detected by
the HRI. We predict that ~40 unknown faint or embedded Class III sources remain
to be discovered in X-rays in the HRI/ISOCAM overlapping area, down to a limit
of L_X ~ 3 \times 1E28 erg/s. We show that the bulk of these unknown Class III
sources should be made of low- to very low-mass stars. Prospects for future
detections with XMM-Newton and Chandra are discussed.

</DOC>
<DOC>
<DOCNO> 119479 </DOCNO>
Abundances of Stars in the Galactic Bulge Obtained Using the Keck


  We report on detailed abundances of giants in the Galactic bulge, measured
with the HIRES echelle spectrograph on the 10-m Keck telescope. We also review
other work on the bulge field population and globular clusters using
Keck/HIRES. Our new spectra have 3 times the resolution and higher S/N than
previous spectra obtained with 4m telescopes. We are able to derive $\log g$
from Fe II lines and excitation temperature from Fe I lines, and do not rely on
photometric estimates for these parameters. We confirm that the iron abundance
range extends from -1.6 to +0.55 dex. The improved resolution and S/N of the
Keck spectra give [Fe/H] typically 0.1 to 0.2 dex higher than previous studies
of bulge stars more metal rich than the Sun. Alpha elements are enhanced even
for stars at the Solar metallicity (as is the case for bulge globular
clusters). We confirm our earlier abundance ananlysis of bulge giants and find
that Mg and Ti are enhanced relative to Ca and Si even up to [Fe/H]=+0.55. We
also resport the first reliable estimates of the bulge oxygen abundance. Our
element ratios confirm that bulge giants have a clearly identifiable chemical
signature and suggest a rapid formation timescale for the bulge.

</DOC>
<DOC>
<DOCNO> 71571 </DOCNO>
Hard Diffraction and Unitarity


  A short survey of the role of unitarity for hard diffractive cross-sections
is given

</DOC>
<DOC>
<DOCNO> 152544 </DOCNO>
Exact Solutions for Cosmological Models with a Scalar Field


  We consider the existence of a Noether symmetry in the scalar-tensor theory
of gravity in flat Friedman Robertson Walker (FRW) cosmology. The forms of
coupling function $\omega(\phi)$ and generic potential $V(\phi)$ are obtained
by requiring the existence of a Noether symmetry for such theory. We derive
exact cosmological solutions of the field equations from a point-like
Lagrangian.

</DOC>
<DOC>
<DOCNO> 71616 </DOCNO>
Flavor symmetry breaking effects on SU(3) Skyrmion


  We study the massive SU(3) Skyrmion model to investigate the flavor symmetry
breaking (FSB) effects on the static properties of the strange baryons in the
framework of the rigid rotator quantization scheme combined with the improved
Dirac quantization one. Both the chiral symmetry breaking pion mass and FSB
kinetic terms are shown to improve $c$ the ratio of the strange-light to
light-light interaction strengths and $\bar{c}$ that of the strange-strange to
light-light.

</DOC>
<DOC>
<DOCNO> 120173 </DOCNO>
Probing the galactic center by gravitational lensing


  The nature of Galactic Center could be probed by lensing experiments capable
of testing the spatial and velocity distributions of stars nearby and beyond
it. Several hypotheses are possible (e.g. massive neutrino condensation, boson
star) which avoid the shortcomings of the supermassive black hole model.

</DOC>
<DOC>
<DOCNO> 70815 </DOCNO>
Defect models of cosmic structure in light of the new CMB data


  Defect models of cosmic structure formation have faced a number of difficult
challenges over recent years. Yet interestingly, new CMB data does not show
strong evidence for secondary oscillations in the anisotropy power. Here I
review the current standing of the cosmic defect models of structure formation
in light of the current data.

</DOC>
<DOC>
<DOCNO> 119650 </DOCNO>
From Stars to Super-planets: the Low-Mass IMF in the Young Cluster IC348


  We investigate the low-mass population of the young cluster IC348 down to the
deuterium-burning limit, a fiducial boundary between brown dwarf and planetary
mass objects, using a new and innovative method for the spectral classification
of late-type objects. Using photometric indices, constructed from HST/NICMOS
narrow-band imaging, that measure the strength of the 1.9 micron water band, we
determine the spectral type and reddening for every M-type star in the field,
thereby separating cluster members from the interloper population. Due to the
efficiency of our spectral classification technique, our study is complete from
approx 0.7 Msun to 0.015 Msun. The mass function derived for the cluster in
this interval, dN/dlogM \propto M^{0.5}, is similar to that obtained for the
Pleiades, but appears significantly more abundant in brown dwarfs than the mass
function for companions to nearby sun-like stars. This provides compelling
observational evidence for different formation and evolutionary histories for
substellar objects formed in isolation vs. as companions. Because our
determination of the IMF is complete to very low masses, we can place
interesting constraints on the role of physical processes such as fragmentation
in the star and planet formation process and the fraction of dark matter in the
Galactic halo that resides in substellar objects.

</DOC>
<DOC>
<DOCNO> 12816 </DOCNO>
The BCS model and the off shell Bethe ansatz for vertex models


  We study the connection between the BCS pairing model and the inhomogeneous
vertex model. The two spectral problems coincide in the quasi-classical limit
of the off-shell Bethe Ansatz of the disordered six vertex model. The latter
problem is transformed into an auxiliary spectral problem which corresponds to
the diagonalization of the integrals of motion of the BCS model. A generating
functional whose quasi classical expansion leads to the constants of motion of
the BCS model and in particular the Hamiltonian, is identified.

</DOC>
<DOC>
<DOCNO> 72004 </DOCNO>
Orthogonal U(1)'s, Proton Stability and Extra Dimensions


  In models with a low quantum gravity scale, one might expect that all
operators consistent with gauge symmetries are present in the low-energy
effective theory. If this is the case, some mechanism must be present to
adequately suppress operators that violate baryon number. Here we explore the
possibility that the desired suppression is a consequence of an additional,
spontaneously-broken, non-anomalous U(1) symmetry that is orthogonal to
hypercharge. We show that successful models can be constructed in which the
additional particle content necessary to cancel anomalies is minimal, and
compatible with the constraints from precision electroweak measurements and
gauge unification. If unification is sacrificed, and only the new U(1) and its
associated Higgs fields live in the bulk, it is possible that the gauge field
zero mode and first few Kaluza-Klein excitations lie within the kinematic reach
of the Tevatron. For gauge couplings not much smaller than that of hypercharge,
we show that these highly leptophobic states could evade detection at Run I,
but be discovered at Run II. Our scenario presents an alternative to the
`cartographic' solution to baryon number violation in which leptons and quarks
are separated in an extra dimension.

</DOC>
<DOC>
<DOCNO> 150922 </DOCNO>
Elastic scattering and bound states in the Aharonov-Bohm potential


  We consider the elastic scattering and bound states of charged quantum
particles moving in the Aharonov-Bohm and an attractive $\rho^{-2}$ potential
in a partial wave approach. Radial solutions of the stationary Schr\"{o}dinger
equation are specified in such a way that the Hamiltonian of the problem is
self-adjoint. It is shown that they are not uniquely fixed but depend on open
parameters. The related physical consequences are discussed. The scattering
cross section is calculated and the energy spectrum of bound states is
obtained.

</DOC>
<DOC>
<DOCNO> 68209 </DOCNO>
Resonant Spin-Flavor Precession Solution to the Solar Neutrino Problem


  We have found allowed squared mass difference, magnetic field, mixing angle -
regions for the Resonant Spin-Flavor Precession Solution to the Solar Neutrino
Problem fitted with the data of all acting solar neutrino experiments. The
typical mass difference region varying in dependence on the mixing angle is
allowed for some discrete magnetic field regions in a wide range for the fixed
neutrino transition magnetic moment. Except of the first allowed range with the
lowest field strength the magnetic field amplitude within other discrete
allowed regions depend essentially on the shape of a regular magnetic field
profile in the convective zone of the Sun. For the non-zero neutrino mixing one
can find at 99.9% C.L. an upper limit on the mixing, originated by the
non-observation of electron antineutrinos in the SuperKamiokande detector. This
limit occurs also sensitive to the magnetic field profile. While at 67% C.L.
there is another more stringent upper limit coming from inconsistency of the
gallium experiments with others. A new allowed region appears in the case of an
additional assumption that the Homestake data are 1.3 times less than the
experimental event rate.

</DOC>
<DOC>
<DOCNO> 152405 </DOCNO>
Supersymmetry and finite-temperature strings


  We describe finite temperature N=4 superstrings in D=5 by an effective
four-dimensional supergravity of the thermal winding modes that can become
tachyonic and trigger the instabilities at the Hagedorn temperature. Using a
domain-wall ansatz, exact solutions to special BPS-type first order equations
are found. They preserve half of the supersymmetries, contrary to the standard
perturbative superstring at finite temperature that breaks all supersymmetries.
Our solutions show no indication of any tachyonic instability and provide
evidence for a new BPS phase of finite temperature superstrings that is stable
for all temperatures. This would have important consequences for a stringy
description of the early universe.

</DOC>
<DOC>
<DOCNO> 84744 </DOCNO>
Hamiltonian systems with boundaries


  Lately, to provide a solid ground for quantization of the open string theory
with a constant B-field, it has been proposed to treat the boundary conditions
as hamiltonian constraints.
  It seems that this proposal is quite general and should be applicable to a
wide range of models defined on manifolds with boundaries. The goal of the
present paper is to show how the boundary conditions can arise as constraints
in a purely algebraic fashion within the Hamiltonian approach without any
reference to the Lagrangian formulation of the theory. The construction of the
boundary Dirac brackets is also given and some subtleties are pointed out.
  We consider four examples of field theories with boundaries: the topological
sigma model, the open string theory with and without a constant $B$-field and
electrodynamics with topological term.
  A curious result for electrodynamics on a manifold with boundaries is
presented.

</DOC>
<DOC>
<DOCNO> 10204 </DOCNO>
Anelastic relaxation and $^{139}$La NQR in La$_{2-x}$Sr$_x$CuO$_4$


  Anelastic relaxation and $^{139}$La NQR relaxation
measurements in La$_{2-x}$Sr$_x$CuO$_4$ for Sr content x around 2 and 3
percent, are presented and discussed in terms of spin and lattice excitations
and ordering processes. It is discussed how the phase diagram of
La$_{2-x}$Sr$_x$CuO$_4$ at the boundary between the antiferromagnetic (AF) and
the spin-glass phase (x = 0.02) could be more complicate than previous thought,
with a transition to a quasi-long range ordered state at T = 150 K, as
indicated by recent neutron scattering data. On the other hand, the $^{139}$La
NQR spectra are compatible with a transition to a conventional AF phase around
T = 50 K, in agreement with the phase diagram commonly accepted in the
literature. In this case the relaxation data, with a peak of magnetic origin in
the relaxation rate around 150 K at 12 MHz and the anelastic counterparts
around 80 K in the kHz range, yield the first evidence in
La$_{1.98}$Sr$_{0.02}$CuO$_4$ of freezing involving simultaneously lattice and
spin excitations. This excitation could correspond to the motion of charged
stripes.

</DOC>
<DOC>
<DOCNO> 69963 </DOCNO>
Constraints on both bilinear and trilinear R-parity violating couplings


  We consider neutrino masses generated at tree level and at one loop, through
fermion--sfermion loop diagrams, in the MSSM with R-parity violation. Using the
$(3\times 3)$ mass and mixing matrices for three generations of neutrinos and
the present experimental results on neutrinos from laboratories and
astrophysics simultaneously, we put bounds on both trilinear ($\lambda_{ijk},
\lambda'_{ijk}$) and bilinear ($\mu_{e},\mu_\mu,\mu_\tau$) R-parity-violating
couplings.

</DOC>
<DOC>
<DOCNO> 40509 </DOCNO>
The e p -> e' p eta reaction at and above the S11(1535) baryon resonance


  New cross sections for the reaction e p -> ep eta are reported for total
center of mass energy W = 1.5--1.86 GeV and invariant momentum transfer Q^2 =
0.25--1.5 GeV^2. This large kinematic range allows extraction of important new
information about response functions, photocouplings, and eta N coupling
strengths of baryon resonances. Expanded W coverage shows sharp structure at W
\~ 1.7 GeV; this is shown to come from interference between S and P waves and
can be interpreted in terms of known resonances. Improved values are derived
for the photon coupling amplitude for the S11(1535) resonance.

</DOC>
<DOC>
<DOCNO> 70305 </DOCNO>
A Field Theoretic Investigation of Spin in QCD


  Utilizing the kinematical boost in light-front formalism one can address the
issue of relativistic spin operators in an arbitrary reference frame. In the
gauge $A^+=0$, the interaction dependent transverse spin operators can be
separated into three parts. In analogy with the helicity sum rule, we propose a
transverse spin sum rule. We perform a one loop renormalization of the
transverse spin operator and show that the counterterm needed is the same as
the linear mass counterterm in the light-front QCD Hamiltonian.

</DOC>
<DOC>
<DOCNO> 120636 </DOCNO>
Mapping the star formation history of Mrk86: I. Data and models


  We have obtained optical (BVR, [OIII]5007 and Halpha), near infrared (JHK)
imaging and long-slit optical spectroscopy for the Blue Compact Dwarf galaxy
Mrk86 (NGC2537). In this paper, the first of two, we present optical-near-
infrared colors and emission-line fluxes for the currently star-forming
regions, intemediate aged starburst and underlying stellar population. We also
describe the evolutionary synthesis models used in Paper II. The R and Halpha
luminosity distributions of the galaxy star-forming regions show maxima at
M_R=-9.5 and L_Halpha=10^37.3 erg s^-1. The underlying stellar population shows
an exponential surface brigthness profile with central value, mu_E,0=21.5 mag
arcsec^-2, and scale, alpha=0.88 kpc, both measured in the R-band image. In the
galaxy outer regions, dominated by this component, no significant color
gradients are observed. Finally, a set of evolutionary synthesis models have
been developed, covering a wide range in metallicity and burst strength.

</DOC>
<DOC>
<DOCNO> 7732 </DOCNO>
Room Temperature Organic Superconductor?


  The electron--phonon coupling in fullerene C28 has been calculated from first
principles. The value of the associated coupling constant lambda/N(0) is found
to be a factor three larger than that associated with C60. Assuming similar
values of the density of levels at the Fermi surface N(0) and of the Coulomb
pseudopotential for C28-based solids as those associated with alkali-doped
fullerides A3C60, one obtains Tc(C28) \approx 8 Tc(C60).

</DOC>
<DOC>
<DOCNO> 151636 </DOCNO>
Rotations and e, $\nu$ Propagators, Part III


  In Parts I and II we showed that e, $\nu$ propagators can be derived from
rotation invariant projection operators, thereby providing examples of how
quantities with spacetime symmetry can be obtained by constraining rotationally
symmetric objects. One constraint is the restriction of the basis; only two
kinds of bases were considered, one for the electron and one for the neutrino.
In this part, we find that, of a wide range of bases each consistent with the
constraint process, only the two kinds of bases considered in Parts I and II
give spacetime symmetric propagators. We interpret the result geometrically.
The spinor representation is unfaithful in four dimensional Euclidean space
which explains why spin 1/2 wave functions have four, not two, components. Then
we show how a basis relates to two planes in four dimensional Euclidean space.
A pair of planes spanning two or three dimensions does not allow spacetime
symmetry. Spacetime symmetry requires two planes that span four dimensions.
  PACS: 11.30.-j, 11.30.Cp, and 03.65.Fd

</DOC>
<DOC>
<DOCNO> 100306 </DOCNO>
Statistical Properties of Convex Minorants of Random Walks and Brownian


  This paper calculates several useful statistical properties of the convex
minorant process generated by random walk processes. In particular, we
calculate the statistics of the longest segment in the convex minorant of a
random walk of a given length. In addition, we calculate the probability that
the convex minorant of a random walk of length N is composed of exactly m
segments; we give an exact formula for the expected number of segments in the
convex minorant. We obsevere that some of this analysis can be meaningful for
the case of Brownian motion on finite intervals; we can calculate exact
formulas for the density of the length of the longest segment in the convex
minorant of Brownian motion on finite intervals.

</DOC>
<DOC>
<DOCNO> 10155 </DOCNO>
Dynamics of vortex tangle without mutual friction in superfluid $^4$He


  A recent experiment has shown that a tangle of quantized vortices in
superfluid $^4$He decayed even at mK temperatures where the normal fluid was
negligible and no mutual friction worked. Motivated by this experiment, this
work studies numerically the dynamics of the vortex tangle without the mutual
friction, thus showing that a self-similar cascade process, whereby large
vortex loops break up to smaller ones, proceeds in the vortex tangle and is
closely related with its free decay. This cascade process which may be covered
with the mutual friction at higher temperatures is just the one at zero
temperature Feynman proposed long ago. The full Biot-Savart calculation is made
for dilute vortices, while the localized induction approximation is used for a
dense tangle. The former finds the elementary scenario: the reconnection of the
vortices excites vortex waves along them and makes them kinked, which could be
suppressed if the mutual friction worked. The kinked parts reconnect with the
vortex they belong to, dividing into small loops. The latter simulation under
the localized induction approximation shows that such cascade process actually
proceeds self-similarly in a dense tangle and continues to make small vortices.
Considering that the vortices of the interatomic size no longer keep the
picture of vortex, the cascade process leads to the decay of the vortex line
density. The presence of the cascade process is supported also by investigating
the classification of the reconnection type and the size distribution of
vortices. The decay of the vortex line density is consistent with the solution
of the Vinen's equation which was originally derived on the basis of the idea
of homogeneous turbulence with the cascade process. The obtained result is
compared with the recent Vinen's theory.

</DOC>
<DOC>
<DOCNO> 8800 </DOCNO>
Electronic structure of self-assembled quantum dots: comparison between


  We have calculated the exchange, correlation, and total electronic energy of
a realistic InAs self-assembled quantum dot embedded in a GaAs matrix as a
function of the number of electrons in the dot. The many-body interactions have
been treated using the local spin density approximation (LSDA) to density
functional theory (DFT) and diffusion quantum Monte Carlo (DMC), so that we may
quantify the error introduced by LSDA. The comparison shows that the LSDA
errors are about 1-2 meV per electron for the system considered. These errors
are small enough to justify the use of LSDA calculations to test models of
self-assembled dots against current experimental measurements.

</DOC>
<DOC>
<DOCNO> 120103 </DOCNO>
The Nature of High-Redshift Galaxies


  Using semi-analytic models of galaxy formation set within the Cold Dark
Matter (CDM) merging hierarchy, we investigate several scenarios for the nature
of the high-redshift ($z \ga 2$) Lyman-break galaxies (LBGs). We consider a
``collisional starburst'' model in which bursts of star formation are triggered
by galaxy-galaxy mergers, and find that a significant fraction of LBGs are
predicted to be starbursts. This model reproduces the observed comoving number
density of bright LBGs as a function of redshift and the observed luminosity
function at $z\sim 3$ and $z\sim 4$, with a reasonable amount of dust
extinction. Model galaxies at $z \sim 3$ have star formation rates, half-light
radii, I-K colours, and internal velocity dispersions that are in good
agreement with the data. Global quantities such as the star formation rate
density and cold gas and metal content of the Universe as a function of
redshift also agree well. Two ``quiescent'' models without starbursts are also
investigated. In one, the star formation efficiency in galaxies remains
constant with redshift, while in the other, it scales inversely with disc
dynamical time, and thus increases rapidly with redshift. The first quiescent
model is strongly ruled out as it does not produce enough high redshift
galaxies once realistic dust extinction is accounted for. The second quiescent
model fits marginally, but underproduces cold gas and very bright galaxies at
high redshift. A general conclusion is that star formation at high redshift
must be more efficient than locally. The collisional starburst model appears to
accomplish this naturally without violating other observational constraints.

</DOC>
<DOC>
<DOCNO> 178707 </DOCNO>
On the Observation of Phase Transitions in Collisions of Elementary


  We investigate the excitation function of directed flow, which can provide a
clear signature of the creation of the QGP and demonstrate that the minimum of
the directed flow does not correspond to the softest point of the EoS for
isentropic expansion. A novel technique measuring the compactness is introduced
to determine the QGP transition in relativistic-heavy ion collisions: The QGP
transition will lead to higher compression and therefore to higher compactness
of the source in coordinate space. This effect can be observed by pion
interferometry. We propose to measure the compactness of the source in the
appropriate principal axis frame of the compactness tensor in coordinate space.

</DOC>
<DOC>
<DOCNO> 116422 </DOCNO>
The Grating Accelerator


  In optics, a reflective grating is a conducting surface with a ripple. The
typical use of such a grating involves an incident electromagnetic wave with
wave vector k in the x-z plane, and interference effects lead to a discrete set
of reflected waves also with wave vectors in the x-z plane. Consider, instead,
an incident plane electromagnetic wave with wave vector in the y-z plane and
polarization in the x direction: We show that for small ripples, this leads to
a reflected wave plus two surface waves that are attenuated exponentially with
z. For certain values of the grating wavelength and the optical wavelength, the
component of the phase velocity of the surface waves is the speed of light c.
In this case, a charged particle moving with v_x ~ c could extract energy from
the wave, which is the principle of the "grating accelerator".

</DOC>
<DOC>
<DOCNO> 120897 </DOCNO>
Radio astronomical imaging in the presence of strong radio interference


  Radio-astronomical observations are increasingly contaminated by
interference, and suppression techniques become essential. A powerful candidate
for interference mitigation is adaptive spatial filtering. We study the effect
of spatial filtering techniques on radio astronomical imaging. Current
deconvolution procedures such as CLEAN are shown to be unsuitable to spatially
filtered data, and the necessary corrections are derived. To that end, we
reformulate the imaging (deconvolution/calibration) process as a sequential
estimation of the locations of astronomical sources. This not only leads to an
extended CLEAN algorithm, the formulation also allows to insert other array
signal processing techniques for direction finding, and gives estimates of the
expected image quality and the amount of interference suppression that can be
achieved. Finally, a maximum likelihood procedure for the imaging is derived,
and an approximate ML image formation technique is proposed to overcome the
computational burden involved. Some of the effects of the new algorithms are
shown in simulated images. Keywords: Radio astronomy, synthesis imaging,
parametric imaging, interference mitigation, spatial filtering, maximum
likelihood, minimum variance, CLEAN.

</DOC>
<DOC>
<DOCNO> 70746 </DOCNO>
Hard exclusive photoproduction of $\Phi$ and $J/\Psi$ mesons


  We present predictions for differential cross sections for the reaction
$\gamma p \to \Phi p$ and give an outlook to which extent our calculations may
be generalized to the photoproduction of $J/\Psi$ mesons. Our results are
obtained within perturbative QCD treating the proton as a quark-diquark system.

</DOC>
<DOC>
<DOCNO> 118652 </DOCNO>
The Evolution of X-ray Clusters and the Entropy of the Intra Cluster


  The thermodynamics of the diffuse, X-ray emitting gas in clusters of galaxies
is determined by gravitational processes associated with shock heating,
adiabatic compression, and non-gravitational processes such as heating by SNe,
stellar winds, activity in the central galactic nucleus, and radiative cooling.
The effect of gravitational processes on the thermodynamics of the Intra
Cluster Medium (ICM) can be expressed in terms of the ICM entropy S ~
ln(T/\rho^{2/3}). We use a generalized spherical model to compute the X-ray
properties of groups and clusters for a range of initial entropy levels in the
ICM and for a range of mass scales, cosmic epochs and background cosmologies.
We find that the statistical properties of the X-ray clusters strongly depend
on the value of the initial excess entropy. Assuming a constant, uniform value
for the excess entropy, the present-day X-ray data are well fitted for the
following range of values K_* = kT/\mu m_p \rho^{2/3} = (0.4\pm 0.1) \times
10^{34} erg cm^2 g^{-5/3} for clusters with average temperatures kT>2 keV; K_*
= (0.2\pm 0.1) \times 10^{34} erg cm^2 g^{-5/3} for groups and clusters with
average temperatures kT<2 keV. These values correspond to different excess
energy per particle of kT \geq 0.1 (K_*/0.4\times 10^{34}) keV. The dependence
of K_* on the mass scale can be well reproduced by an epoch dependent external
entropy: the relation K_* = 0.8(1+z)^{-1}\times 10^{34} erg cm^2 g^{-5/3} fits
the data over the whole temperature range. Observations of both local and
distant clusters can be used to trace the distribution and the evolution of the
entropy in the cosmic baryons, and ultimately to unveil the typical epoch and
the source of the heating processes.

</DOC>
<DOC>
<DOCNO> 72122 </DOCNO>
Stability, Causality, and Lorentz and CPT Violation


  Stability and causality are investigated for quantum field theories
incorporating Lorentz and CPT violation. Explicit calculations in the quadratic
sector of a general renormalizable lagrangian for a massive fermion reveal that
no difficulty arises for low energies if the parameters controlling the
breaking are small, but for high energies either energy positivity or
microcausality is violated in some observer frame. However, this can be avoided
if the lagrangian is the sub-Planck limit of a nonlocal theory with spontaneous
Lorentz and CPT violation. Our analysis supports the stability and causality of
the Lorentz- and CPT-violating standard-model extension that would emerge at
low energies from spontaneous breaking in a realistic string theory.

</DOC>
<DOC>
<DOCNO> 85217 </DOCNO>
Production and detection of relic dilatons in string cosmology


  This paper summarizes the contribution presented at the {\sl IX Marcel
Grossmann Meeting} (Rome, July 2000). It is stressed, in particular, that a
non-relativistic background of ultra-light dilatons, produced in the context of
string cosmology, could represent today a significant fraction of cold dark
matter. If the dilaton mass lies within the resonant band of present
gravitational antennas, a stochastic dilaton background with a nearly critical
density could be visible, in principle, already at the level of sensitivity of
the detectors in operation and presently under construction.

</DOC>
<DOC>
<DOCNO> 84969 </DOCNO>
Decoherence Caused by Topology in a Time-Machine Spacetime


  Non-relativistic quantum theory of non-interacting particles in the spacetime
containing a region with closed time-like curves (time-machine spacetime) is
considered with the help of the path-integral technique. It is argued that, in
certain conditions, a sort of superselection may exist for evolution of a
particle in such a spacetime. All types of evolution are classified by the
number $n$ defined as the number of times the particle returns back to its
past. It corresponds also to the topological class of trajectories of the
particle. The evolutions corresponding to different values of $n$ are
non-coherent. The amplitudes corresponding to such evolutions may not be
superposed. Instead of one evolution operator, as in the conventional
(coherent) description, evolution of the particle is described by a family
$U_n$ of partial evolution operators. This is done in analogy with the
formalism of quantum theory of measurements, but with essential new features in
the dischronal region (the region with closed time-like curves) of the
time-machine spacetime. Partial evolution operators $U_n$ are equal to
integrals over the topological classes of paths if the evolution begins and
ends in the chronal regions. If the evolution begins or/and ends in the
dischronal region, the integral over the topological class should be multiplied
by a certain projector to give the partial evolution operator $U_n$. Thus
defined partial evolution operators possess the property of generalized
unitarity and multiplicativity. The part of evolution containing repeated
returning backward in time cannot be factorized: all backward passages of the
particle have to be considered as a single act, that cannot be presented as
gradually, step by step, passing through `causal loops'.

</DOC>
<DOC>
<DOCNO> 8664 </DOCNO>
Quasiparticle Localization Transition in Dirty Superconductors


  In this paper, a delocalization-localization transition within the
superconducting state is explored. The symmetries of the Bogoliubov deGennes
 Hamiltonian endow the two associated superconducting phases - the thermal
metal and the thermal insulator-, and the critical point between them with
properties that are in stark contrast with analogous phases in normal systems.
Here, for systems preserving spin rotational invariance and time reversal
symmetry in three dimensions, the transition is shown to be of a different
universality class from its normal partner by extracting and comparing the
localization length exponent. The density of states, which may be regarded as
the 'order parameter' for the field theory describing the superconducting
system, is studied for its unusual properties about criticality.

</DOC>
<DOC>
<DOCNO> 7758 </DOCNO>
Photonic excess noise and wave localization


  This is a theory for the effect of localization on the super-Poissonian noise
of radiation propagating through an absorbing disordered waveguide.
Localization suppresses both the mean photon current I and the noise power P,
but the Fano factor P/I is found to remain unaffected. For strong absorption
the Fano factor has the universal value 1+3f/2 (with f the Bose-Einstein
function), regardless of whether the waveguide is long or short compared to the
localization length.

</DOC>
<DOC>
<DOCNO> 121982 </DOCNO>
The Ephemeris and Dipping Spectral Behavior of X1624-490


  We present striking results from Rossi X-ray Timing Explorer (RXTE)
observations of the 21-hr low mass X-ray binary X1624-490, showing five complex
dips in unprecedented detail. For the first time, dipping is detected up to 15
keV. Prominent flares are also observed in the light curves, limited to
energies above 8 keV. Spectra selected by intensity during dip episodes can be
well fit with a two-component model consisting of a point-like blackbody from
the neutron star and progressive covering of an extended Comptonized region,
presumably an accretion disk corona (ADC), corrected for photons scattered into
and out of the X-ray beam by a interstellar dust halo. We find that the outer
regions of the absorber are highly ionized and that electron scattering is
totally responsible for the X-ray attenuation during shallow dipping. The
timescales of dip ingress and egress indicate that the envelope of material
absorbing the ADC has smaller angular size than the ADC itself, and that the
ADC is likely limited to a height-to-radius ratio of 10%, rather than being
spherical in extent. In addition, we have analyzed 4.5 yrs of RXTE All Sky
Monitor (ASM) coverage to derive the first accurate orbital ephemeris for
X1624-490, with phase zero (the time of dip centers) well-described by the
relation 2450088.63918(69) + N*0.869907(12) (JD).

</DOC>
<DOC>
<DOCNO> 118945 </DOCNO>
Oscillations and convective motion in stars with URCA shells


  It is shown that in presence of URCA shell pulsational energy losses due to
neutrino emission and nonequilibrium beta heating are much less than energy
losses by excitation of short-wavelength acoustic waves. Convective motion in
presence of URCA shell is considered, and equations generalizing the mean free
path model of convection are derived.

</DOC>
<DOC>
<DOCNO> 116961 </DOCNO>
Analysis of Thermally Induced Frequency Shift for the Spallation Neutron


  The Spallation Neutron Source (SNS) Front-End Systems Group at Lawrence
Berkeley National Lab (LBNL) is developing a Radio Frequency Quadrupole (RFQ)
to accelerate an H- beam from 65 keV to 2.5 MeV at the operating frequency of
402.5 MHz. The 4 section, 3.7 meter long RFQ is a 4 vane structure operating at
6% duty factor. The cavity walls are made from OFE Copper with a GlidCop outer
layer to add mechanical strength. A set of 12 cooling channels in the RFQ
cavity walls are fed and controlled separately from 4 channels embedded in the
vanes. An ANSYS finite-element model has been developed to calculate the
deformed shape of the cavity for given RF heat loads and cooling water
temperatures. By combining the FEA results with a SUPERFISH RF cavity
simulation, the relative shift in frequency for a given change in coolant
temperature or heat load can be predicted. The calculated cavity frequency
sensitivity is -33 kHz per 1 degC change in vane water temperature with
constant-temperature wall water. The system start-up transient was also studied
using the previously mentioned FEA model. By controlling the RF power ramp rate
and the independent wall and vane cooling circuit temperatures, the system
turn-on time can be minimized while limiting the frequency shift.

</DOC>
<DOC>
<DOCNO> 169621 </DOCNO>
Quantum network architecture of tight-binding models with substitution


  We study a two-spin quantum Turing architecture, in which discrete local
rotations \alpha_m of the Turing head spin alternate with quantum controlled
NOT-operations. Substitution sequences are known to underlie aperiodic
structures. We show that parameter inputs \alpha_m described by such sequences
can lead here to a quantum dynamics, intermediate between the regular and the
chaotic variant. Exponential parameter sensitivity characterizing chaotic
quantum Turing machines turns out to be an adequate criterion for induced
quantum chaos in a quantum network.

</DOC>
<DOC>
<DOCNO> 121828 </DOCNO>
A deep submillimetre survey of the Galactic Centre


  We present first results from a submillimetre continuum survey of the
Galactic Centre `Central Molecular Zone' (CMZ), made with SCUBA on the James
Clerk Maxwell Telescope. SCUBA's scan-map mode has allowed us to make extremely
wide-field maps of thermal dust emission with unprecedented speed and
sensitivity. We also discuss some issues related to the elimination of
artefacts in scan-map data. Our simultaneous 850/450 micron maps have a total
size of approximately 2.8 x 0.5 degrees (400 x 75 pc) elongated along the
galactic plane. They cover the Sgr A region-including Sgr A*, the circumnuclear
disc, and the +20 km/s and +50 km/s clouds; the area around the Pistol; Sgr
B2-the brightest feature on the map; and at their Galactic Western and Eastern
edges the Sgr C and Sgr D regions. There are many striking features such as
filaments and shell-like structures, as well as point sources such as Sgr A*
itself. The total mass in the Central Molecular Zone is greater than that
revealed in previous optically-thin molecular line maps by a factor of ~3, and
new details are revealed on scales down to 0.33 pc across this 400 pc wide
region.

</DOC>
<DOC>
<DOCNO> 123261 </DOCNO>
Halo enrichment by disrupted globular clusters


  We study the evolution of the galactic globular cluster system to determine
its initial mass-function and the fraction of halo stars that could have come
from disrupted globular clusters. We study the cluster evolution under the
influence of two destruction mechanisms: Two-body relaxation and dynamical
friction. New results of N-body simulations are used for the lifetimes of
clusters dissolving under the influence of two-body relaxation.
  Two different mass-functions are studied: A gaussian initial distribution in
log(M_C) with mean mass and scatter similar to what one observes for the
galactic globular cluster system, and a power-law distribution resembling what
is seen for clusters in merging and interacting galaxies. We find that in the
inner parts of the galaxy, both distributions evolve in such a way that they
are consistent with the observations. In the outer parts, a gaussian initial
distribution gives the better fit. This might change however if elliptic orbits
are considered, or there are undiscovered low-mass clusters in the galactic
halo. In any case, only a small fraction of the stellar halo of the Milky Way
originated in globular clusters.

</DOC>
<DOC>
<DOCNO> 170201 </DOCNO>
A reply to "Quantum Clock Synchronization"


  Recently a protocol for Quantum Clock Synchronization (QCS) of remote clocks
using quantum entanglement was proposed by Jozsa et al. This method has the
goal of eliminating the random noise present in classical synchronization
techniques. However, as stated QCS depends on the two members of each entangled
pair undergoing the same unitary evolution even while being transported to
different locations. This is essentially equivalent to a perfect Eddington Slow
Clock Transfer protocol and thus, not an improvement over classical techniques.
We will discuss this and suggest ways in which QCS may still be used.

</DOC>
<DOC>
<DOCNO> 174552 </DOCNO>
Chemical Equilibrium and Isotope Temperatures


  The measurement and interpretation of isotopic yield ratios in heavy ion
reactions at intermediate and high energies are discussed and the usefulness of
these observables for establishing equilibrium properties and for determining
thermodynamic parameters is illustrated. The examples are mainly taken from
work performed with lighter projectiles at intermediate and high energies and
from studies of spectator reactions at relativistic energies. As an
application, the caloric curve of nuclei, as derived for Au on Au collisions,
is introduced and discussed.

</DOC>
<DOC>
<DOCNO> 151307 </DOCNO>
On a Boundary CFT Description of Nonperturbative N=2 Yang-Mills Theory


  We describe a simple method for determining the strong-coupling BPS spectrum
of four dimensional N=2 supersymmetric Yang-Mills theory. The idea is to
represent the magnetic monopoles and dyons in terms of D-brane boundary states
of a non-compact d=2 N=2 Landau-Ginzburg model. In this way the quantum
truncated BPS spectrum at the origin of the moduli space can be directly mapped
to the finite number of primary fields of the superconformal minimal models.

</DOC>
<DOC>
<DOCNO> 99448 </DOCNO>
Weyl structures for parabolic geometries


  Motivated by the rich geometry of conformal Riemannian manifolds and by the
recent development of geometries modeled on homogeneous spaces $G/P$ with $G$
semisimple and $P$ parabolic, Weyl structures and preferred connections are
introduced in this general framework. In particular, we extend the notions of
scales, closed and exact Weyl connections, and Rho--tensors, we characterize
the classes of such objects, and we use the results to give a new description
of the Cartan bundles and connections for all parabolic geometries.

</DOC>
<DOC>
<DOCNO> 9610 </DOCNO>
Gradient descent learning in and out of equilibrium


  Relations between the off thermal equilibrium dynamical process of on-line
learning and the thermally equilibrated off-line learning are studied for
potential gradient descent learning. The approach of Opper to study on-line
Bayesian algorithms is extended to potential based or maximum likelihood
learning. We look at the on-line learning algorithm that best approximates the
off-line algorithm in the sense of least Kullback-Leibler information loss. It
works by updating the weights along the gradient of an effective potential
different from the parent off-line potential. The interpretation of this off
equilibrium dynamics holds some similarities to the cavity approach of
Griniasty. We are able to analyze networks with non-smooth transfer functions
and transfer the smoothness requirement to the potential.

</DOC>
<DOC>
<DOCNO> 170214 </DOCNO>
The Liar-paradox in a Quantum Mechanical Perspective


  In this paper we concentrate on the nature of the liar paradox as a cognitive
entity; a consistently testable configuration of properties. We elaborate
further on a quantum mechanical model [Aerts, Broekaert, Smets 1999] that has
been proposed to analyze the dynamics involved, and we focus on the
interpretation and concomitant philosophical picture. Some conclusions we draw
from our model favor an effective realistic interpretation of cognitive
reality.

</DOC>
<DOC>
<DOCNO> 169817 </DOCNO>
Ground state cooling, quantum state engineering and study of decoherence


  We investigate single ions of $^{40}Ca^+$ in Paul traps for quantum
information processing. Superpositions of the S$_{1/2}$ electronic ground state
and the metastable D$_{5/2}$ state are used to implement a qubit. Laser light
on the S$_{1/2} \leftrightarrow$ D$_{5/2}$ transition is used for the
manipulation of the ion's quantum state. We apply sideband cooling to the ion
and reach the ground state of vibration with up to 99.9% probability. Starting
from this Fock state $|n=0>$, we demonstrate coherent quantum state
manipulation. A large number of Rabi oscillations and a ms-coherence time is
observed. Motional heating is measured to be as low as one vibrational quantum
in 190 ms. We also report on ground state cooling of two ions.

</DOC>
<DOC>
<DOCNO> 71770 </DOCNO>
Quark structure of f0(980) from the radiative decays phi(1020)->gamma


  Partial widths of the radiative decays $\phi(1020)\to\gamma f_0(980)$,
$\gamma\eta$, $\gamma\eta'$, $\gamma\pi^0$ and $f_0(980)\to\gamma\gamma$ are
calculated assuming all mesons under consideration to be $q\bar q$ states:
$\phi(1020)$ is dominantly an $s\bar s$ state ($n\bar n$ component $\lesssim
1%$), $\eta$, $\eta'$ and $\pi^0$ are standard $q\bar q$ states, $\eta = n\bar
n\cos\theta - s\bar s\sin\theta$ and $\eta'=n\bar n\sin\theta + s\bar
s\cos\theta$ with $\theta\simeq 37^\circ$, and $f_0(980)$ is the $q\bar q$
meson with the flavour wave function $n\bar n\cos\phi + s\bar s \sin\phi$.
Calculated partial widths for the decays $\phi\to\gamma \eta$, $\gamma\eta'$,
$\gamma\pi^0$ are in a reasonable agreement with experiment. The measured value
of the branching ratio $BR(\phi\to\gamma f_0(980))$ requires $25^\circ\le
|\phi|\le 90^\circ$; for the decay $f_0(980)\to\gamma\gamma$ the agreement with
data is reached at either $77^\circ\le\phi\le 93^\circ$ or
$(-54^\circ)\le\phi\le (-38^\circ)$. Simultaneous analysis of the decays
$\phi(1020)\to\gamma f_0(980)$ and $f_0(980)\to\gamma\gamma$ provides arguments
in favour of the solution with negative mixing angle $\phi =-48^\circ\pm
6^\circ$.

</DOC>
<DOC>
<DOCNO> 117568 </DOCNO>
Co Detection of the Extremely Red Galaxy HR10


  CO J = 5 - 4 and J = 2 - 1 emission lines were detected towards the extremely
red galaxy (ERG) HR10 (J164502+4626.4) at z=1.44. The CO intensities imply a
molecular gas mass M(H2) of 1.6 x 10^{11} h^{-2}_50 solar masses, and, combined
with the intensity of the dust continuum, a gas-to-dust mass ratio around
200-400 (assuming galactic values for the conversion factors). The peak of the
CO lines are at the same redshift as the [O II]3727 line, but blue- shifted by
430 km s^{-1} from the Halpha line. These CO detections confirm the previous
results that HR10 is a highly obscured object with a large thermal far-infrared
luminosity and a high star-formation rate. The overall properties of HR10 (CO
detection, L_FIR to L'_CO ratio, and FIR to radio flux ratio) clearly favour
the hypothesis that its extreme characteristics are related to star-formation
processes rather than to a hidden AGN.

</DOC>
<DOC>
<DOCNO> 100808 </DOCNO>
Novikov - Shubin signatures, II


  This paper continues math.DG/9903140. Here we construct a linking form on the
torsion part of middle dimensional extended L^2 homology and cohomology of
odd-dimensional manifolds. We give a geometric necessary condition when this
linking form is hyperbolic. We compute this linking form in case when the
manifold bounds. We introduce and study new numerical invariants of the linking
form: the Novikov - Shubin signature and the torsion signature. We compute
these invariants explicitly for manifolds with $\pi_1 = Z$ in terms of the
Blanchfield form. We develop a notion of excess for extensions of torsion
modules and show how this concept can be used to guarantee vanishing of the
torsion signature.

</DOC>
<DOC>
<DOCNO> 84184 </DOCNO>
Type 0 Brane Inflation from Mirage Cosmology


  We consider a three-dimensional brane-universe moving in a Type 0 String
background. The motion induces on the brane a cosmological evolution which, for
some range of the parameters, exhibits an inflationary phase.

</DOC>
<DOC>
<DOCNO> 100991 </DOCNO>
A class of T-stable (P1 x ... x P1)'s in G/B


  Let G be a connected complex semi-simple group, B a Borel subgroup of G, and
T a maximal torus in B. We construct a class of smooth T-stable subvarieties
inside the flag variety G/B, each of which is an embedding of a product of
projective lines.

</DOC>
<DOC>
<DOCNO> 12150 </DOCNO>
Dynamical correlations in one-dimensional charge-transfer insulators


  The single-particle spectral function and the density response of a two band
Emery model for CuO chains is calculated for large on-site Cu repulsion U and
large on-site energy difference \Delta. For U>>U-\Delta>>t the eigenfunctions
are products of charge and spin parts, which allows analytical calculation of
spectral functions in that limit. For other parameters numerical
diagonalization is used. The low energy hole carriers are shown to be the
one-dimensional analogs of the Zhang-Rice singlets. The validity of the
one-band model is discussed. The results are relevant to the interpretation of
photoemission and EELS experiments on SrCuO2 and Sr2CuO3 .

</DOC>
<DOC>
<DOCNO> 72262 </DOCNO>
Solving the nucleon spin puzzle based on the chiral quark soliton model


  An incomparable feature of the chiral quark soliton model as compared with
many other effective models like the MIT bag model is that it can give
reasonable predictions not only for quark distributions but also for antiquark
distributions. This will be exemplified by the argument on the positivity
constraint for $\bar{u} (x) + \bar{d} (x)$ as well as the Soffer inequality for
quark and antiquark distributions. We also explain how the model can resolve
the so-called nucleon spin puzzle without assuming large gluon polarization at
the low energy scale.

</DOC>
<DOC>
<DOCNO> 101804 </DOCNO>
Solutions of Inverse Problems for Variational Calculus


  The paper studies the harmonic maps on a direction between a Riemannian space
and a generalized Lagrange space. Also, it is proved there that the solutions
of C^2 class of certain ODEs or PDEs are harmonic maps, in the sense of this
paper.

</DOC>
<DOC>
<DOCNO> 7975 </DOCNO>
Frustration and sound attenuation in structural glasses


  Three classes of harmonic disorder systems (Lennard-Jones like glasses,
percolators above threshold, and spring disordered lattices) have been
numerically investigated in order to clarify the effect of different types of
disorder on the mechanism of high frequency sound attenuation. We introduce the
concept of frustration in structural glasses as a measure of the internal
stress, and find a strong correlation between the degree of frustration and the
exponent alpha that characterizes the momentum dependence of the sound
attenuation $Gamma(Q)$$\simeq$$Q^\alpha$. In particular, alpha decreases from
about d+1 in low-frustration systems (where d is the spectral dimension), to
about 2 for high frustration systems like the realistic glasses examined.

</DOC>
<DOC>
<DOCNO> 101030 </DOCNO>
Frame formalism for the N-dimensional quantum Euclidean spaces


  We sketch our recent application of a non-commutative version of the Cartan
`moving-frame' formalism to the quantum Euclidean space $R^N_q$, the space
which is covariant under the action of the quantum group $SO_q(N)$. For each of
the two covariant differential calculi over $R^N_q$ based on the $R$-matrix
formalism, we summarize our construction of a frame, the dual inner
derivations, a metric and two torsion-free almost metric compatible covariant
derivatives with a vanishing curvature. To obtain these results we have
developed a technique which fully exploits the quantum group covariance of
$R^N_q$. We first find a frame in the larger algebra $\Omega^*(R^N_q) \cocross
\uqs$. Then we define homomorphisms from $R^N_q \cocross U_q^{\pm}{so(N)}$ to
$R^N_q$ which we use to project this frame in $\Omega^*(R^N_q)$.

</DOC>
<DOC>
<DOCNO> 117429 </DOCNO>
Clustering of galaxies at faint magnitudes


  Significant uncertainties exist in the measured amplitude of the angular
two-point correlation function of galaxies at magnitudes $I\approx26$ and
fainter. Published results from HST and ground-based galaxy catalogs seem to
differ by as much as a factor of 3, and it is not clear whether the correlation
amplitude as a function of magnitude increases or decreases in the faintest
magnitude bins. In order to clarify the situation, we present new results from
both ground-based and HST galaxy catalogs. The angular two-point correlation
function as a function of limiting R and I magnitudes was computed from a
galaxy catalog created from the Hubble Deep Field - South (HDF-S) WFPC2 image.
The measured amplitudes of the correlation at an angular separation of 1 arcsec
are consistent with those measured in the Northern counter part of the field.
The flanking fields (FF fields) of the Hubble deep fields were used to extend
the magnitude range for which we compute correlation amplitudes towards
brighter magnitude bins. This allows easier comparison of the amplitudes to
ground based data. The newly measured correlation amplitudes as a function of
magnitude limit were compared to previously published measurements at larger
separations. For this comparison, the correlation function was approximated by
a power law with an index of 0.8. The scatter in the correlation amplitudes is
too large to be explained by random errors. We argue that the most likely cause
is the assumption that the shape of the correlation function does not depend on
the magnitude limit.

</DOC>
<DOC>
<DOCNO> 100094 </DOCNO>
Sur le th\'eor\`eme de l'indice des \'equations diff\'erentielles


  This paper works out the structure of singular points of p-adic differential
equations (i.e. differential modules over the ring of functions analytic in
some annulus with external radius 1). Surprisingly results look like in the
formal case (differential modules over a one variable power series field) but
proofs are much more involved. However, unlike in the Turritin theorem, even
after ramification, in the p-adic theory there are irreducible objects of rank
>1. The first part is devoted to the definition of p-adic slopes and to a
decomposition along p-adic slopes theorem. The case of slope 0 (p-adic
analogue of the regular singular case) was already studied in the paper with
the same title but number II [Ann. of Math. (2) 146 (1997), 345-410]. The
second part states several index existence theorems and index formulas. As a
consequence, vertices of the Newton polygon built from p-adic slopes are
proved to have integral components (analogue of the Hasse-Arf theorem). After
the work of the second author, existence of index implies finitness of p-adic
(Monsky-Washnitzer) cohomology for affine varieties over finite fields. The
end of the paper outlines the construction of a p-adic-coefficient category
over curves (over a finite field) with all needed finitness properties.
  In the paper with the same title but number IV [Invent. Math. 143 (2001),
629-672], further insights are given.

</DOC>
<DOC>
<DOCNO> 120780 </DOCNO>
The non-thermal radiation - Cluster merger connection


  There is compelling evidence that at least some clusters of galaxies are
powerful sources of non-thermal radiation. In all cases where this radiation
has been detected, a general trend is that high energy densities of cosmic rays
and correspondingly low values of the average magnetic field are required in
order to have a self-consistent picture of the multiwavelength observations.
Mergers of clusters of galaxies might provide large enough cosmic ray injection
rates and at the same time provide the mechanism for the heating of the
intracluster medium to the observed temperatures. In this paper we analyze
critically all the components that play a role in the non-thermal emission of
clusters during a merger, with special attention to mergers occurred in the
past of the cluster. We outline the consequences of this model for high energy
gamma ray observations and for Faraday rotation measurements of the
intracluster magnetic field.

</DOC>
<DOC>
<DOCNO> 118898 </DOCNO>
Detailed Analysis of the Pulsations During and After Bursts from the


  The hard X-ray bursts observed during both major outbursts of the Bursting
Pulsar (GRO J1744-28) show pulsations near the neutron star spin frequency with
an enhanced amplitude relative to that of the persistent emission. Consistent
with previous work, we find that the pulsations within bursts lag behind their
expected arrival times based upon the persistent pulsar ephemeris. For an
ensemble of 1293 bursts recorded with the Burst and Transient Source
Experiment, the average burst pulse time delay is 61.0 +/- 0.8 ms in the 25 -
50 keV energy range and 72 +/- 5 ms in the 50 - 100 keV band. The residual time
delay from 10 to 240 s following the start of the burst is 18.1 +/- 0.7 ms (25
- 50 keV). A significant correlation of the average burst time delay with burst
peak flux is found. Our results are consistent with the model of the pulse time
lags presented by Miller (1996).

</DOC>
<DOC>
<DOCNO> 178594 </DOCNO>
Statistical Behavior of Finite-Size Partially Equilibrated Systems


  We examine deviations from Boltzmann-Gibbs statistics for partially
equilibrated systems of finite size. We find that such systems are
characterized by the Levy distribution whose non-extensivity parameter is
related to the number of internally equilibrated subsystems and to correlations
among them. This concept is applied to Quark-Gluon Plasma formation.

</DOC>
<DOC>
<DOCNO> 84271 </DOCNO>
Acoustics of early universe. II. Lifshitz vs. gauge-invariant theories


  Appealing to classical methods of order reduction, we reduce the Lifshitz
system to a second order differential equation. We demonstrate its equivalence
to well known gauge-invariant results. For a radiation dominated universe we
express the metric and density corrections in their exact forms and discuss
their acoustic character.

</DOC>
<DOC>
<DOCNO> 101789 </DOCNO>
Grothendieck Groups of Poisson Vector Bundles


  A new invariant of Poisson manifolds, a Poisson K-ring, is introduced.
Hypothetically, this invariant is more tractable than such invariants as
Poisson (co)homology. A version of this invariant is also defined for arbitrary
algebroids. Basic properties of the Poisson K-ring are proved and the Poisson
K-rings are calculated for a number of examples. In particular, for the zero
Poisson structure the K-ring is the ordinary K-theory of the manifold and for
the dual space to a Lie algebra the K-ring is the ring of virtual
representations of the Lie algebra. It is also shown that the K-ring is an
invariant of Morita equivalence. Moreover, the K-ring is a functor on a
category, the weak Morita category, which generalizes the notion of Morita
equivalence of Poisson manifolds.

</DOC>
<DOC>
<DOCNO> 102895 </DOCNO>
Semidensities on Odd Symplectic Supermanifolds


  We consider semidensities on a supermanifold E with an odd symplectic
structure. We define a new $\Delta$-operator action on semidensities as the
proper framework for Batalin-Vilkovisky formalism. We establish relations
between semidensities on E and differential forms on Lagrangian surfaces. We
apply these results to Batalin-Vilkovisky geometry. Another application is to
(1.1)-codimensional surfaces in E. We construct a kind of pull-back of
semidensities to such surfaces. This operation and the $\Delta$-operator are
used for obtaining integral invariants for (1.1)-codimensional surfaces.

</DOC>
<DOC>
<DOCNO> 9127 </DOCNO>
A conformal field theory description of the paired and parafermionic


  We extend the construction of the effective conformal field theory for the
Jain hierarchical fillings proposed in cond-mat/9912287 to the description of a
quantum Hall fluid at non standard fillings nu=m/(pm+2). The chiral primary
fields are found by using a procedure which induces twisted boundary conditions
on the m scalar fields; they appear as composite operators of a charged and
neutral component. The neutral modes describe parafermions and contribute to
the ground state wave function with a generalized Pfaffian term. Correlators of
Ne electrons in the presence of quasi-hole excitations are explicitly given for
m=2.

</DOC>
<DOC>
<DOCNO> 70081 </DOCNO>
Chaotic sources and Percolation of strings


  It is shown that different ways of interacting strings formed in high energy
nucleus-nucleus collisions cause a different strength of the chaoticity
parameter lambda of Bose-Einstein correlations. In particular, in the case of
percolation of strings, lambda shows a peculiar dependence on the string
density, very similar to the dependence of the fractional average cluster size.
In both, the derivative on the string density is maximum at the critical point.
The reasonable agreement with the existing experimental data indicates that
percolation of strings can actually occurs.

</DOC>
<DOC>
<DOCNO> 120550 </DOCNO>
Testing the AGN-Starburst Connection in Seyfert Galaxies


  We use the CO band at 2.3 micron to constrain the populations of young stars
in the central regions of Seyfert galaxies. We report new CO band spectroscopy
of 46 Seyfert galaxies. In most cases, the observed CO indices appear diluted
by the presence of a non-stellar component (most likely, warm dust surrounding
the active nucleus). We used JHKL aperture photometry to estimate the
non-stellar contribution at 2.3 micron. We successfully corrected the CO band
for the dilution for 16 galaxies which were not dominated by the non-stellar
component. Comparing with CO indices measured in elliptical and purely
starbursting galaxies, we find no evidence for strong starbursts in the
majority of these galaxies.

</DOC>
<DOC>
<DOCNO> 80768 </DOCNO>
A study of the 't Hooft loop in SU(2) Yang-Mills theory


  We study the behaviour of the spatial and temporal 't Hooft loop at zero and
finite temperature in the 4D SU(2) Yang-Mills theory, using a new numerical
method. In the deconfined phase $T>T_c$, the spatial 't Hooft loop exhibits a
dual string tension, which vanishes at $T_c$ with 3D Ising-like critical
exponent.

</DOC>
<DOC>
<DOCNO> 39956 </DOCNO>
Search for R-parity Violation in Multilepton Final States in p-barp


  The result of a search for gaugino pair production with a trilepton signature
is reinterpreted in the framework of minimal supergravity (mSUGRA) with
R-parity violation via leptonic lambda Yukawa couplings. The search used 95
pb^{-1} of p-barp collisions at sqrt{s}=1.8 TeV recorded by the D0 detector at
the Fermilab Tevatron. A large domain of the mSUGRA parameter space is excluded
for lambda_{121}, lambda_{122} > 10^{-4}.

</DOC>
<DOC>
<DOCNO> 13125 </DOCNO>
Collective excitations in ferrimagnetic Heisenberg ladders


  We study ground-state properties and the low-lying excitations of Heisenberg
spin ladders composed of two ferrimagnetic chains with alternating site spins
$(S_1>S_2)$ by using the bosonic Dyson-Maleev formalism and Lanczos numerical
techniques. The emphasis is on properties of the ferrimagnetic phase which is
stable for antiferromagnetic interchain couplings $J_{\perp}\geq 0$. There are
two basic implications of the underlying lattice structure: (i) the spin-wave
excitations form folded acoustic and optical branches in the extended Brillouin
zone and (ii) the ground state parameters (such as the on-site magnetizations
and spin-stiffness constant) show a crossover behavior in the weak-coupling
region $0<J_{\perp}<1$. The above peculiarities of the ladder ferrimagnetic
state are studied up to second order in the quasiparticle interaction and by a
numerical diagonalization of ladders containing up to N=12 rungs. The presented
results for the ground-state parameters and the excitation spectrum can be used
in studies on the low-temperature thermodynamics of ferrimagnetic ladders.

</DOC>
<DOC>
<DOCNO> 101106 </DOCNO>
Moduli space intersection duality between Regge surfaces and 2D


  Deformation theory for 2-dimensional dynamical triangulations with N vertices
is discussed by exploiting the geometry of the moduli space of Euclidean
polygons. Such an analysis provides an explicit connection among Regge
surfaces, dynamical triangulations and the Witten-Kontsevich model. We show
that a natural set of Regge measures and a triangulation counting of relevance
for dynamical triangulations are directly connected with intersection theory
over the compactified moduli space of genus g Riemann surfaces with N
punctures.The Regge measures in question provide volumes of the open strata in
moduli space. It is also argued that the arguments presented here offer
evidence of a form of topological S-duality between Regge calculus and DT
theory.

</DOC>
<DOC>
<DOCNO> 122828 </DOCNO>
Cosmological models: theory and observations


  The current status of the theoretical and observational cosmology is
reviewed.

</DOC>
<DOC>
<DOCNO> 71764 </DOCNO>
Comments on CKM elements


  The sensitivity of determination of elements of the Cabibbo-Kobayashi-Maskawa
(CKM) matrix to experimental inputs (particularly $|V_{cb}|$) is discussed and
caution in assigning probable errors is urged.

</DOC>
<DOC>
<DOCNO> 13742 </DOCNO>
Distribution of sizes of erased loops of loop-erased random walks in two


  We show that in the loop-erased random walk problem, the exponent
characterizing probability distribution of areas of erased loops is
superuniversal. In d-dimensions, the probability that the erased loop has an
area A varies as A^{-2} for large A, independent of d, for 2 <= d <= 4. We
estimate the exponents characterizing the distribution of perimeters and areas
of erased loops in d = 2 and 3 by large-scale Monte Carlo simulations. Our
estimate of the fractal dimension z in two-dimensions is consistent with the
known exact value 5/4. In three-dimensions, we get z = 1.6183 +- 0.0004. The
exponent for the distribution of durations of avalanche in the
three-dimensional abelian sandpile model is determined from this by using
scaling relations.

</DOC>
<DOC>
<DOCNO> 9054 </DOCNO>
Novel glassy behavior in a ferromagnetic p-spin model


  Recent work has suggested the existence of glassy behavior in a ferromagnetic
model with a four-spin interaction. Motivated by these findings, we have
studied the dynamics of this model using Monte Carlo simulations with
particular attention being paid to two-time quantities. We find that the system
shares many features in common with glass forming liquids. In particular, the
model exhibits: (i) a very long-lived metastable state, (ii) autocorrelation
functions that show stretched exponential relaxation, (iii) a non-equilibrium
timescale that appears to diverge at a well defined temperature, and (iv) low
temperature aging behaviour characteristic of glasses.

</DOC>
<DOC>
<DOCNO> 178753 </DOCNO>
The Past and Future of Coulomb Dissociation in Hadron- and Astrophysics


  Breakup reactions are generally quite complicated, they involve nuclear and
electromagnetic forces including interference effects. Coulomb dissociation is
an especially simple and important mechanism since the perturbation due to the
electric field of the nucleus is exactly known. Therefore firm conclusions can
be drawn from such measurements. Electromagnetic matrixelements, radiative
capture cross-sections and astrophysical S-factors can be extracted from
experiments. We describe the basic theory, give analytical results for higher
order effects in the dissociation of neutron halo nuclei and briefly review the
experimental results obtained up to now. Some new applications of Coulomb
dissociation for nuclear astrophysics and nuclear structure physics are
discussed.

</DOC>
<DOC>
<DOCNO> 84460 </DOCNO>
Some Properties of Non-linear $\sigma$-Models in Noncommutative Geometry


  We introduce non-linear $\sigma$-models in the framework of noncommutative
geometry with special emphasis on models defined on the noncommutative torus.
We choose as target spaces the two point space and the circle and illustrate
some characteristic features of the corresponding $\sigma$-models. In
particular we construct a $\sigma$-model instanton with topological charge
equal to 1. We also define and investigate some properties of a noncommutative
analogue of the Wess-Zumino-Witten model.

</DOC>
<DOC>
<DOCNO> 9166 </DOCNO>
Disorder Effects in Superconducting Multiple Loop Quantum


  A theoretical study is presented on a number N of resistively shunted
Josephson junctions connected in parallel as a disordered 1D array by
superconducting wiring in such a manner that there are N-1 individual SQUID
loops with arbitrary shape formed.

</DOC>
<DOC>
<DOCNO> 11184 </DOCNO>
Finite-Size Scaling in the transverse Ising Model on a Square Lattice


  Energy eigenvalues and order parameters are calculated by exact
diagonalization for the transverse Ising model on square lattices of up to 6x6
sites. Finite-size scaling is used to estimate the critical parameters of the
model, confirming universality with the three-dimensional classical Ising
model. Critical amplitudes are also estimated for both the energy gap and the
ground-state energy.

</DOC>
<DOC>
<DOCNO> 119395 </DOCNO>
Space-borne global astrometric surveys: the hunt for extra-solar planets


  The proposed global astrometry mission {\it GAIA}, recently recommended
within the context of ESA's Horizon 2000 Plus long-term scientific program,
appears capable of surveying the solar neighborhood within $\sim$ 200 pc for
the astrometric signatures of planets around stars down to the magnitude limit
of $V$=17 mag, which includes late M dwarfs at 100 pc. Realistic end-to-end
simulations of the GAIA global astrometric measurements have yielded first
quantitative estimates of the sensitivity to planetary perturbations and of the
ability to measure their orbital parameters. Single Jupiter-mass planets around
normal solar-type stars appear detectable up to 150 pc ($V\le $12 mag) with
probabilities $\ge$ 50 per cent for orbital periods between $\sim$2.5 and
$\sim$8 years, and their orbital parameters measured with better than 30 per
cent accuracy to about 100 pc. Jupiter-like objects (same mass and period as
our giant planet) are found with similar probabilities up to 100 pc.These first
experiments indicate that the {\it GAIA} results would constitute an important
addition to those which will come from the other ongoing and planned
planet-search programs. These data combined would provide a formidable testing
ground on which to confront theories of planetary formation and evolution.

</DOC>
<DOC>
<DOCNO> 83144 </DOCNO>
A tableau methodology for deontic conditional logics


  In this paper we present a theorem proving methodology for a restricted but
significant fragment of the conditional language made up of (boolean
combinations of) conditional statements with unnested antecedents. The method
is based on the possible world semantics for conditional logics. The KEM label
formalism, designed to account for the semantics of normal modal logics, is
easily adapted to the semantics of conditional logics by simply indexing labels
with formulas. The inference rules are provided by the propositional system KE+
- a tableau-like analytic proof system devised to be used both as a refutation
and a direct method of proof - enlarged with suitable elimination rules for the
conditional connective. The theorem proving methodology we are going to present
can be viewed as a first step towards developing an appropriate algorithmic
framework for several conditional logics for (defeasible) conditional
obligation.

</DOC>
<DOC>
<DOCNO> 121042 </DOCNO>
The Real Space Power Spectrum of the PSCz Survey from 0.01 to 300 h/Mpc


  We report a measurement of the real space (not redshift space) power spectrum
of galaxies over four and a half decades of wavenumber, 0.01 to 300 h/Mpc, from
the IRAS Point Source Catalog Redshift Survey (PSCz). Since estimates of power
are highly correlated in the nonlinear regime, we also report results for the
prewhitened power spectrum, which is less correlated. The inferred bias between
optically-selected APM and IRAS-selected PSCz galaxies is about 1.15 at linear
scales < 0.3 h/Mpc, increasing to about 1.4 at nonlinear scales > 1 h/Mpc. The
nonlinear power spectrum of PSCz shows a near power-law behaviour to the
smallest scales measured, with mild upward curvature in the broad vicinity of
1.5 h/Mpc. Contrary to the prediction of unbiased Dark Matter models, there is
no prominent inflection at the linear-nonlinear transition scale, and no
turnover at the transition to the stable clustering regime. The nonlinear power
spectrum of PSCz requires scale-dependent bias: all Dark Matter models without
scale-dependent bias are ruled out with high confidence.

</DOC>
<DOC>
<DOCNO> 8654 </DOCNO>
Dependence of the physical properties of


  We present a comparative study of the magnetic, transport and structural
properties of $Nd_{0.5}Ca_{0.5}MnO_{3+\delta}$ [$\delta=$ 0.02(1) and 0.04(1)].
We have found significant differences between the low temperature magnetic
orders and the magnetization curves below $T_{CO}\approx 250 K$ of the two
samples. In particular one component of the magnetic moment presents a
ferromagnetic coupling between the $(0 0 1)$ planes ($P bnm$ setting) deviating
the angle between neighboring $Mn$ ions from $180^o$ (perfect CE order) to
$150^o$ [$\delta=0.02(1)$] and $130^o$ [$\delta= 0.04(1)$]. These results imply
a remarkable $\delta$ dependence which is discussed in the light of a
non-random spatial distribution of defects in the perfect charge order scheme.

</DOC>
<DOC>
<DOCNO> 71674 </DOCNO>
The 7/11 Rule and an Estimate of m_rho


  We summarize some recent work on large-Nc sum rules.

</DOC>
<DOC>
<DOCNO> 39767 </DOCNO>
Protons in near earth orbit


  The proton spectrum in the kinetic energy range 0.1 to 200 GeV was measured
by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at
an altitude of 380 km. Above the geomagnetic cutoff the observed spectrum is
parameterized by a power law. Below the geomagnetic cutoff a substantial second
spectrum was observed concentrated at equatorial latitudes with a flux ~ 70
m^-2 sec^-1 sr^-1. Most of these second spectrum protons follow a complicated
trajectory and originate from a restricted geographic region.

</DOC>
<DOC>
<DOCNO> 118729 </DOCNO>
On the Physics of Primordial Magnetic Fields


  There are at present more then 30 theories about the origin of cosmic
magnetic fields at galactic and intergalactic scales. Most of them rely on
concepts of elementary particle physics, like phase transitions in the early
Universe, string theory and processes during the inflationary epoch. Here we
present some more astrophysical arguments to provide some guidance through this
large number and variety of models. Especially the fact that the evolution of
magnetic fields depends on the spatial coherence scale of the fields leds to
some interesting conclusions, which may rule out the majority of the
theoretical scenarios. In principle one has to distinguish between the
large-scale and small-scale magnetic fields. Large scale fields are defined as
those as becoming sub-horizon at that redshift at which the mass energy density
becomes equal to the photon energy density, which we name as equality. Small
scale fields which are sub-horizon even before equality, i.e. with scales lower
than (present) few Mpc cannot survive the radiation era and cannot reach
recombination, because of the effects of magnetic diffusion and photon
diffusion. Therefore mechanisms based on phase transitions become unlike, as
they provide magnetic fields on scales smaller than the horizon. Thus, the
observed galactic and intergalactic fields, which are small scales in our
terminology must be created after recombination by normal plasma processes
during the protogalactic evolution. The large scale fields instead were
produced during inflation and may have noticeable implications for the
formation of the large scale structure of the Universe. The inclusion of large
scale magnetic fields may improve present Cold Dark Matter theories of
structure formation.

</DOC>
<DOC>
<DOCNO> 121343 </DOCNO>
High column densities and low extinctions of gamma-ray bursts: Evidence


  We analyze a complete sample of gamma-ray burst afterglows, and find X-ray
evidence for high column densities of gas around them. The column densities are
in the range 1e+22-1e+23/cm2, which is right around the average column density
of Galactic giant molecular clouds. We also estimate the cloud sizes to be
10-30 pc, implying masses greater than about 1e+5 solar masses. This strongly
suggests that gamma-ray bursts lie within star forming regions, and therefore
argues against neutron star mergers and for collapses of massive stars as their
sources. The optical extinctions, however, are 10-100 times smaller than
expected from the high column densities. This confirms theoretical findings
that the early hard radiation from gamma-ray bursts and their afterglows can
destroy the dust in their environment, thus carving a path for the afterglow
light out of the molecular cloud. Because of the self-created low extinction
and location in star-forming regions, we expect gamma-ray bursts to provide a
relatively unbiased sample of high-redshift star formation. Thus they may help
resolve what is the typical environment of high-redshift star formation.

</DOC>
<DOC>
<DOCNO> 151300 </DOCNO>
Geometry of the Nonabelian DBI Dyonic Instanton


  We introduce a calculus of the Lie algebra valued functions present in
Tseytlin's proposal for the nonabelian DBI action, and apply it to show that
the recently found dyonic instanton is a solution of the full nonabelian DBI
action. The geometry of this solution exhibits a new effect of ``blowing-up''
of the brane, which was not present in the case of the brane realisation of
monopoles. We interpret this solution as the superposition of the D0 brane and
fundamental string F1 which connects two separated D4 branes. Both F1 and D0
are delocalised in the ``blown-up'' region between two separated D4 branes.

</DOC>
<DOC>
<DOCNO> 72192 </DOCNO>
On the eta-eta' complex in the SD-BS approach


  The bound-state Schwinger-Dyson and Bethe-Salpeter (SD-BS) approach is
chirally well-behaved and provides a reliable treatment of the eta-eta' complex
although a ladder approximation is employed. Allowing for the effects of the
SU(3) flavor symmetry breaking in the quark-antiquark annihilation, leads to
the improved eta-eta' mass matrix.

</DOC>
<DOC>
<DOCNO> 83200 </DOCNO>
Robustness of Regional Matching Scheme over Global Matching Scheme


  The paper has established and verified the theory prevailing widely among
image and pattern recognition specialists that the bottom-up indirect regional
matching process is the more stable and the more robust than the global
matching process against concentrated types of noise represented by clutter,
outlier or occlusion in the imagery. We have demonstrated this by analyzing the
effect of concentrated noise on a typical decision making process of a
simplified two candidate voting model where our theorem establishes the lower
bounds to a critical breakdown point of election (or decision) result by the
bottom-up matching process are greater than the exact bound of the global
matching process implying that the former regional process is capable of
accommodating a higher level of noise than the latter global process before the
result of decision overturns. We present a convincing experimental verification
supporting not only the theory by a white-black flag recognition problem in the
presence of localized noise but also the validity of the conjecture by a facial
recognition problem that the theorem remains valid for other decision making
processes involving an important dimension-reducing transform such as principal
component analysis or a Gabor transform.

</DOC>
<DOC>
<DOCNO> 84826 </DOCNO>
Lorentzian regularization and the problem of point-like particles in


  The two purposes of the paper are (1) to present a regularization of the
self-field of point-like particles, based on Hadamard's concept of ``partie
finie'', that permits in principle to maintain the Lorentz covariance of a
relativistic field theory, (2) to use this regularization for defining a model
of stress-energy tensor that describes point-particles in post-Newtonian
expansions (e.g. 3PN) of general relativity. We consider specifically the case
of a system of two point-particles. We first perform a Lorentz transformation
of the system's variables which carries one of the particles to its rest frame,
next implement the Hadamard regularization within that frame, and finally come
back to the original variables with the help of the inverse Lorentz
transformation. The Lorentzian regularization is defined in this way up to any
order in the relativistic parameter 1/c^2. Following a previous work of ours,
we then construct the delta-pseudo-functions associated with this
regularization. Using an action principle, we derive the stress-energy tensor,
made of delta-pseudo-functions, of point-like particles. The equations of
motion take the same form as the geodesic equations of test particles on a
fixed background, but the role of the background is now played by the
regularized metric.

</DOC>
<DOC>
<DOCNO> 150483 </DOCNO>
Duality and Combinatorics of Long Strings in ADS3


  The counting of long strings in ADS3, in the context of Type IIB string
theory on $ADS_3 \times S^3 \times T^4$, is used to exhibit the action of the
duality group $O(5,5;Z)$, and in particular its Weyl Subgroup $S_5 \bowtie
Z_2$, in the non-perturbative phenomena associated with continuous spectra of
states in these backgrounds. The counting functions are related to states in
Fock spaces. The symmetry groups also appear in the structure of
compactifications of instanton moduli spaces on $T^4$.

</DOC>
<DOC>
<DOCNO> 123330 </DOCNO>
The change in the inclination angle of the non-eclipsing binary SS


  Eclipses in the 14.4-day period double-lined binary SS Lac were observed
photographically and visually early in the 20th century, but stopped some 50 or
60 years ago. This has been explained by the presence of a distant third star
in the system, which has now been detected spectroscopically with a period of
679 days. The plane of the orbit of the binary is changing relative to the line
of sight in response to perturbations from this third object. A recent analysis
by Milone et al. (M00) of all photometric material available for the system,
including a re-measurement of original Harvard plates, has confirmed earlier
reports of changes in the depth of the eclipses as a function of time, which
are due to the third star. In this paper we discuss our detailed analysis of
the eclipse amplitude measurements, and extract from them information on the
change in the inclination angle of the binary over the last century. Our use of
a much improved ephemeris for the system by Torres & Stefanik was found to be
crucial, and prompted us to re-determine all the amplitudes from the historical
data at our disposal, including the Harvard material used by M00.
Systematically lower measurements on the branches of the minima were properly
accounted for, and we made use of both a linear approximation to the time
variation of the inclination angle and a more realistic model based on the
theory of three-body interactions ("regression of the nodes" effect). The nodal
cycle is found to be about 600 yr, within which TWO eclipse "seasons" occur,
each lasting about 100 yr. The non-eclipsing status of the system is expected
to continue until the beginning of the 23rd century.

</DOC>
<DOC>
<DOCNO> 8441 </DOCNO>
Thermodynamic Properties of d_{x^2-y^2}+id_{xy} Superconductor


  In view of the current interest in d_{x^{2}-y^{2}}+id_{xy} superconductors
some of their thermodynamic properties have been studied to obtain relevant
information for experimental verification. The temperature dependence of the
specific heat and superfluid density show marked differences in
d_{x^{2}-y^{2}}+id_{xy} state compared to the pure d-wave state. A second order
phase transition is observed on lowering the temperature into a
d_{x^{2}-y^{2}}+id_{xy} state from the d_{x^{2}-y^{2}} state with the opening
up of a gap all over the fermi surface. The thermodynamic quantities in
d_{x^{2}-y^{2}}+id_{xy} state are dominated by this gap as in an s-wave
superconductor as opposed to the algebraic temperature dependence in pure
d-wave states coming from the low energy excitations across the node(s).

</DOC>
<DOC>
<DOCNO> 40004 </DOCNO>
Technique for Direct eV-Scale Measurements of the Mu and Tau Neutrino


  Early black hole formation in a core-collapse supernova will abruptly
truncate the neutrino fluxes. The sharp cutoff can be used to make
model-independent time-of-flight neutrino mass tests. Assuming a neutrino
luminosity of $10^{52}$ erg/s per flavor at cutoff and a distance of 10 kpc,
SuperKamiokande can detect an electron neutrino mass as small as 1.8 eV, and
the proposed OMNIS detector can detect mu and tau neutrino masses as small as 6
eV. This {\it Letter} presents the first technique with direct sensitivity to
eV-scale mu and tau neutrino masses.

</DOC>
<DOC>
<DOCNO> 102355 </DOCNO>
Two-dimensional conformal field theory and beyond. Lessons from a


  Two-dimensional conformal field theory (CFT) has several sources: the search
for simple examples of quantum field theory, the description of surface
critical phenomena, the study of (super)string vacua. In the present overview
of the subject we emphasize the role of CFT in bridging the gap between
mathematics and quantum field theory and discuss some new physical concepts
that emerged in the study of CFT models: anomalous dimensions, rational CFT,
braid group statistics. In an aside, at the end of the paper, we share the
misgivings, recently expressed by Penrose, about some dominant trends in
fundamental theoretical physics.

</DOC>
<DOC>
<DOCNO> 67638 </DOCNO>
Making Baryons Below the Electroweak Scale


  I describe a new way for baryogenesis to proceed, which evades many of the
problems of GUT and electroweak scenarios. If the reheat temperature after
inflation is below the electroweak scale, neither GUT baryon production nor
traditional electroweak baryogenesis can occur. However, non-thermal production
of sphaleron configurations via preheating could generate the observed baryon
asymmetry of the universe. Such low scale baryon production is particularly
attractive since it evades a number of strong constraints on reheating from
gravitino and moduli production.

</DOC>
<DOC>
<DOCNO> 39820 </DOCNO>
High Energy Particles from the Universe


  The field of high energy particle astronomy is exciting and rapidly
developing. In the last few years, we have detected extragalactic sources of
intense TeV gamma radiation and individual cosmic ray particles with energies
exceeding 25 Joules. Understanding the workings of astrophysics under extreme
conditions is the primary goal of this field. Also important is the possibility
of using high energy particles from space to probe beyond the standard models
of particle physics and cosmology. This paper presents a review of high energy
particle astronomy using photons, cosmic rays, and neutrinos.

</DOC>
<DOC>
<DOCNO> 178749 </DOCNO>
Masses of the Sub-Nuclear Particles


  The masses of the quarks and leptons are for the most part a mystery to
particle physicists. Currently there seems to be no correlation between the
masses of the elementary particles. This paper is an attempt to formulate a
theory that would begin to explain the relationship between the sub-nuclear
particle masses.

</DOC>
<DOC>
<DOCNO> 120447 </DOCNO>
Galaxy Formation and Chemical Evolution in Hierarchical Hydrodynamical


  We report first results of an implementation of a chemical model in a
cosmological code, based on the Smoothed Particle Hydrodynamics (SPH)
technique. We show that chemical SPH simulations are a promising tool to
provide clues for the understanding of the chemical properties of galaxies in
relation to their formation and evolution in a cosmological framework.

</DOC>
<DOC>
<DOCNO> 120928 </DOCNO>
Mixing through shear instabilities


  In this paper we present the results of numerical simulations of the
Kelvin-Helmholtz instability in a stratified shear layer. This shear
instability is believed to be responsible for extra mixing in differentially
rotating stellar interiors and is the prime candidate to explain the abundance
anomalies observed in many rotating stars. All mixing prescriptions currently
in use are based on phenomenological and heuristic estimates whose validity is
often unclear. Using three-dimensional numerical simulations, we study the
mixing efficiency as a function of the Richardson number and compare our
results with some semi-analytical formalisms of mixing.

</DOC>
<DOC>
<DOCNO> 152439 </DOCNO>
Zero-point field induced mass vs. QED mass renormalization


  Haisch and Rueda have recently proposed a model in which the inertia of
charged particles is a consequence of their interaction with the
electromagnetic zero-point field. This model is based on the observation that
in an accelerated frame the momentum distribution of vacuum fluctuations is not
isotropic. We analyze this issue through standard techniques of relativistic
field theory, first by regarding the field A_mu as a classical random field,
and then by making reference to the mass renormalization procedure in Quantum
Electrodynamics and scalar-QED.

</DOC>
<DOC>
<DOCNO> 12299 </DOCNO>
Matter in Strong Magnetic Fields


  The properties of matter are significantly modified by strong magnetic
fields, $B>>2.35\times 10^9$ Gauss ($1 G =10^{-4} Tesla$), as are typically
found on the surfaces of neutron stars. In such strong magnetic fields, the
Coulomb force on an electron acts as a small perturbation compared to the
magnetic force. The strong field condition can also be mimicked in laboratory
semiconductors. Because of the strong magnetic confinement of electrons
perpendicular to the field, atoms attain a much greater binding energy compared
to the zero-field case, and various other bound states become possible,
including molecular chains and three-dimensional condensed matter. This article
reviews the electronic structure of atoms, molecules and bulk matter, as well
as the thermodynamic properties of dense plasma, in strong magnetic fields,
$10^9G << B < 10^{16}G$. The focus is on the basic physical pictures and
approximate scaling relations, although various theoretical approaches and
numerical results are also discussed. For the neutron star surface composed of
light elements such as hydrogen or helium, the outermost layer constitutes a
nondegenerate, partially ionized Coulomb plasma if $B<<10^{14}G$, and may be in
the form of a condensed liquid if the magnetic field is stronger (and
temperature $<10^6$ K). For the iron surface, the outermost layer of the
neutron star can be in a gaseous or a condensed phase depending on the cohesive
property of the iron condensate.

</DOC>
<DOC>
<DOCNO> 117845 </DOCNO>
ALTAI: Computational code for the simulations of TeV air showers as


  Ground-based atmospheric Cherenkov telescopes are proven to be effective
instruments for observations of very high energy (VHE) gamma-radiation from
celestial objects. For effective use of such technique one needs detailed Monte
Carlo simulations of gamma-ray- and proton/nuclei-induced air showers in Earth
atmosphere. Here we discuss in detail the algorithms used in the numerical code
ALTAI developed particularly for the simulations of Cherenkov light emission
from air showers of energy below 50 TeV. The specific scheme of sampling the
charged particle transport in the atmosphere allows the performance of very
fast and accurate simulations used for interpretation of the VHE gamma-ray
observations.

</DOC>
<DOC>
<DOCNO> 117853 </DOCNO>
Theory of the Interaction of Planetary Nebulae with the Interstellar


  The theory of the interaction of planetary nebulae with the interstellar
medium is important for the interpretation of nebular morphologies that deviate
from point symmetry. It can be used to probe the interstellar medium and its
magnetic field. We emphasize in this review the role of hydrodynamical
instabilities in the interaction.

</DOC>
<DOC>
<DOCNO> 118792 </DOCNO>
The Structure of IR Luminous Galaxies at 100 Microns


  We have observed twenty two galaxies at 100 microns with the Kuiper Airborne
Observatory in order to determine the size of their FIR emitting regions. Most
of these galaxies are luminous far-infrared sources, with L_FIR > 10^11 L_sun.
This data constitutes the highest spatial resolution ever achieved on luminous
galaxies in the far infrared. Our data includes direct measurements of the
spatial structure of the sources, in which we look for departures from point
source profiles. Additionally, comparison of our small beam 100 micron fluxes
with the large beam IRAS fluxes shows how much flux falls beyond our detectors
but within the IRAS beam. Several sources with point- like cores show evidence
for such a net flux deficit. We clearly resolved six of these galaxies at 100
microns and have some evidence for extension in seven others. Those galaxies
which we have resolved can have little of their 100 micron flux directly
emitted by a point-like active galactic nucleus (AGN). Dust heated to ~40 K by
recent bursts of non-nuclear star formation provides the best explanation for
their extreme FIR luminosity. In a few cases, heating of an extended region by
a compact central source is also a plausible option. Assuming the FIR emission
we see is from dust, we also use the sizes we derive to find the dust
temperatures and optical depths at 100 microns which we translate into an
effective visual extinction through the galaxy. Our work shows that studies of
the far infrared structure of luminous infrared galaxies is clearly within the
capabilities of new generation far infrared instrumentation, such as SOFIA and
SIRTF.

</DOC>
<DOC>
<DOCNO> 8025 </DOCNO>
Density of the Fisher zeroes for the Ising model


  The density of the Fisher zeroes, or zeroes of the partition function in the
complex temperature plane, is determined for the Ising model in zero field as
well as in a pure imaginary field i Pi/2. Results are given for the
simple-quartic, triangular, honeycomb, and the kagome lattices. It is found
that the density diverges logarithmically at points along its loci.

</DOC>
<DOC>
<DOCNO> 83183 </DOCNO>
Searching for Spaceships


  We describe software that searches for spaceships in Conway's Game of Life
and related two-dimensional cellular automata. Our program searches through a
state space related to the de Bruijn graph of the automaton, using a method
that combines features of breadth first and iterative deepening search, and
includes fast bit-parallel graph reachability and path enumeration algorithms
for finding the successors of each state. Successful results include a new 2c/7
spaceship in Life, found by searching a space with 2^126 states.

</DOC>
<DOC>
<DOCNO> 120830 </DOCNO>
Global fits for the spectral index of the cosmological curvature


  Best-fit values of the spectral index of the curvature perturbation are
presented, assuming the $\Lambda$CDM cosmology. Apart from the spectral index,
the parameters are the Hubble parameter, the total matter density and the
baryon density. The data points are intended to represent all measurements
which are likely to significantly affect the result. The cosmic microwave
anisotropy is represented by the COBE normalization, and heights of the first
and second peaks given by the latest Boomerang and Maxima data. The slope of
the galaxy correlation function and the matter density contrast on the
$8h^{-1}\Mpc$ scale are each represented by a data point, as are the expected
values of the Hubble parameter and matter density.
 The `low-deuterium' nucleosynthesis value of the baryon density provides a
final data point, the fit giving a value about one standard deviation higher.
The reionization epoch is calculated from the model by assuming that it
corresponds to the collapse of a fraction $f\gsim 10^{-4}$ of matter.
 We consider the case of a scale-independent spectral index, and also the
scale-dependent spectral index predicted by running mass models of inflation.
In the former case, the result is compared with the prediction of models of
inflation based on effective field theory, in which the field value is small on
the Planck scale. Detailed comparison is made with other fits, and other
approaches to the comparison with theory.

</DOC>
<DOC>
<DOCNO> 39743 </DOCNO>
R-values in Low Energy e^+e^- Annihilation


  This presentation briefly summarizes the recent measurements of R-values in
low energy e^+e^- annihilation. The new experiments aimed at reducing the
uncertainties in R-values and performed with the upgraded Beijing Spectrometer
(BESII) at Beijing Electron Positron Collider (BEPC) in Beijing and with CMD-2
and SND at VEEP-2M in Novosibirsk are reviewed and discussed.

</DOC>
<DOC>
<DOCNO> 10476 </DOCNO>
Level correlations in disordered superconducting grains


  I study the quasiparticle level correlations in a grain of a weakly
disordered d-wave superconductor, and show that, in a wide intermediate energy
range, they are characterized by a novel type of universal behavior.

</DOC>
<DOC>
<DOCNO> 116963 </DOCNO>
SLAC Linac RF Performance for LCLS


  The Linac Coherent Light Source (LCLS) project at SLAC uses a dense 15 GeV
electron beam passing through a long undulator to generate extremely bright
x-rays at 1.5 angstroms. The project requires electron bunches with a nominal
peak current of 3.5kA and bunch lengths of 0.020mm (70fs). The bunch
compression techniques used to achieve the high brightness impose challenging
tolerances on the accelerator RF phase and amplitude. The results of
measurements on the existing SLAC linac RF phase and amplitude stability are
summarised and improvements needed to meet the LCLS tolerances are discussed.

</DOC>
<DOC>
<DOCNO> 117710 </DOCNO>
Locally Optimally-Emitting Clouds and the Variable Broad Emission Line


  [abridged] We test the ``locally optimally-emitting clouds'' (LOC) model
against the extensive spectroscopic data base of the Seyfert~1, NGC 5548. The
time-averaged, integrated-light UV broad emission line spectrum from the 1993
{\em HST} monitoring campaign is reproduced via the optimization of three
global geometric parameters: the outer radius, the index controlling the radial
cloud covering fraction of the continuum source, and the integrated cloud
covering fraction. We make an {\em ad~hoc} selection from the range of
successful models, and for a simple spherical BLR geometry we simulate the
emission line light curves for the 1989 {\em IUE} and 1993 {\em HST} campaigns,
using the respective observed UV continuum light curves as drivers. We find
good agreement between the predicted and observed light curves and lags --- a
demonstration of the LOC picture's viability as a means to understanding the
BLR environment. Finally, we discuss the next step in developing the LOC
picture which involves the marriage of echo-mapping techniques with spectral
simulation grids such as those presented here, using the constraints provided
by a high quality, temporally well-sampled spectroscopic data set.

</DOC>
<DOC>
<DOCNO> 120846 </DOCNO>
New theoretical Mass-loss rates of O and B Stars


  We have calculated mass-loss rates for a grid of wind models covering a wide
range of stellar parameters and have derived a mass-loss recipe for two ranges
of effective temperature at either side of the bi-stability jump around
spectral type B1.
  For a large sample of O stars, it is shown that there is now good agreement
between these new theoretical mass-loss rates that take multiple scattering
into account and observations.
  Agreement between the observed and new theoretical wind momenta increases
confidence in the possibility to derive distances to luminous stars in distant
stellar systems using the Wind momentum Luminosity Relation.
  For the winds of the B stars there is an inconsistency in the literature
between various mass-loss rate determinations from observations by different
methods. One group of the determinations for B stars does follow the new
theoretical relation, while another group does not. The lack of agreement
between the observed mass-loss rates derived by different methods may point to
systematic errors in mass-loss determinations from observations for B stars.
  We show that our theoretical mass-loss recipe is reliable and recommend it be
used in evolutionary calculations.

</DOC>
<DOC>
<DOCNO> 69920 </DOCNO>
Three-party entanglement from positronium


  The decay of ortho-positronium into three photons produces a physical
realization of a pure state with three-party entanglement. Its quantum
correlations are analyzed using recent results on quantum information theory,
looking for the final state which has the maximal amount of GHZ-like
correlations. This state allows for a statistical dismissal of local realism
stronger than the one obtained using any entangled state of two spin one-half
particles.

</DOC>
<DOC>
<DOCNO> 119450 </DOCNO>
Mid-Infrared Observations of Normal Star-Forming Galaxies: The Infrared


  We present mid-infrared maps and preliminary analysis for 61 galaxies
observed with the ISOCAM instrument aboard the Infrared Space Observatory. Many
of the general features of galaxies observed at optical wavelengths---spiral
arms, disks, rings, and bright knots of emission---are also seen in the
mid-infrared, except the prominent optical bulges are absent at 6.75 and 15
microns. In addition, the maps are quite similar at 6.75 and 15 microns, except
for a few cases where a central starburst leads to lower 6.75/15 ratios in the
inner region. We also present infrared flux densities and mid-infrared sizes
for these galaxies. The mid-infrared color 6.75/15 shows a distinct trend with
the far-infrared color 60/100. The quiescent galaxies in our sample (60/100 <
0.6) show 6.75/15 near unity, whereas this ratio drops significantly for
galaxies with higher global heating intensity levels. Azimuthally-averaged
surface brightness profiles indicate the extent to which the mid-infrared flux
is centrally concentrated, and provide information on the radial dependence of
mid-infrared colors. The galaxies are mostly well resolved in these maps:
almost half of them have < 10% of their flux in the central resolution element.
A comparison of optical and mid-infrared isophotal profiles indicates that the
optical flux at 4400 Angstroms near the optical outskirts of the galaxies is
approximately eight (seven) times that at 6.75 microns (15 microns), comparable
with observations of the diffuse quiescent regions of the Milky Way.

</DOC>
<DOC>
<DOCNO> 101327 </DOCNO>
A Lax Pair for 2D Euler Equation


  A Lax pair for the 2D Euler equation is found.

</DOC>
<DOC>
<DOCNO> 120240 </DOCNO>
NICMOS Imaging of Candidate Extra-Solar Planetary Systems


  The connection between the formation and growth of planetesimals into larger
bodies and the circumstellar debris disks around young and nascent stars from
which they arise has been the subject of continual speculation, discussion and
inquiry, since the original scenario for such evolution was first expanded upon
by Laplace (1796) following the general proposition by Kant (1755). NICMOS
coronagraphy has enabled both the direct imaging of such circumstellar disks
seen in scattered light about more mature stars (other than b Pictoris)
exhibiting morphologically resolved spatial features, and the detection of
substellar companions (brown dwarfs and extra-solar giant planets) with masses
extending into the Jovian domain for recently formed objects (< a few x 107
years). Exploiting this capability, approximately 18% of the NICMOS IDTs
observing time on HST was dedicated to addressing fundamental questions
relating to the origins of extra-solar systems while exploring the Environments
of Nearby Stars under the umbrella of our EONS project.

</DOC>
<DOC>
<DOCNO> 118687 </DOCNO>
The WARPS survey - IV: The X-ray luminosity-temperature relation of high


  We present a measurement of the cluster X-ray luminosity-temperature relation
out to high redshift (z~0.8). Combined ROSAT PSPC spectra of 91 galaxy clusters
detected in the Wide Angle ROSAT Pointed Survey (WARPS) are simultaneously fit
in redshift and luminosity bins. The resulting temperature and luminosity
measurements of these bins, which occupy a region of the high redshift L-T
relation not previously sampled, are compared to existing measurements at low
redshift in order to constrain the evolution of the L-T relation. We find a
best fit to low redshift (z<0.2) cluster data, at T>1 keV, to be L proportional
to T^(3.15\pm0.06). Our data are consistent with no evolution in the
normalisation of the L-T relation up to z~0.8. Combining our results with ASCA
measurements taken from the literature, we find eta=0.19\pm0.38 (for Omega_0=1,
with 1 sigma errors) where L_Bol is proportional to (1 + z)^eta T^3.15, or
eta=0.60\pm0.38 for Omega_0=0.3. This lack of evolution is considered in terms
of the entropy-driven evolution of clusters. Further implications for
cosmological constraints are also discussed.

</DOC>
<DOC>
<DOCNO> 85261 </DOCNO>
The harmonic gauge condition in the gravitomagnetic equations


  It has been asserted in the literature that the analogy between the linear
and first order slow motion approximation of Einstein equations of General
Relativity (gravitomagnetic equations) and the Maxwell-Lorentz equations of
electrodynamics breaks down if the gravitational potentials are time dependent.
 In this work, we show that this assertion is not correct and it has arisen
from an incorrect limit of the usual harmonic gauge condition, which
drastically changes the physical content of the gravitomagnetic equations.

</DOC>
<DOC>
<DOCNO> 13010 </DOCNO>
Stochastic Dynamics of Time Correlations in Complex Systems with


  In this paper we present the concept of description of random processes in
complex systems with the discrete time. It involves the description of kinetics
of discrete processes by means of the chain of finite-difference non-Markov
equations for time correlation functions (TCF). We have introduced the dynamic
(time dependent) information Shannon entropy $S_i(t)$ where i=0,1,2,3,... as an
information measure of stochastic dynamics of time correlation $(i=0)$ and time
memory (i=1,2,3,...). The set of functions $S_i(t)$ constitute the quantitative
measure of time correlation disorder $(i=0)$ and time memory disorder
(i=1,2,3,...) in complex system. Harnessing the infinite set of orthogonal
dynamic random variables on a basis of Gram-Shmidt orthogonalization procedure
tends to creation of infinite chain of finite-difference non-Markov kinetic
equations for discrete TCF and memory function.The solution of the equations
above thereof brings to the recurrence relations between the TCF and MF of
senior and junior orders. The results obtained offer considerable scope for
attack on stochastic dynamics of discrete random processes in a complex
systems. Application of this technique on the analysis of stochastic dynamics
of RR-intervals from human ECG's shows convincing evidence for a non-Markovian
phenomemena associated with a peculiarities in short and long-range scaling.
This method may be of use in distinguishing healthy from pathologic data sets
based in differences in these non-Markovian properties.

</DOC>
<DOC>
<DOCNO> 101333 </DOCNO>
Newtonian dynamical systems admitting normal blow-up of points


  Class of Newtonian dynamical systems admitting normal blow-up of points in
Riemannian manifolds is considered. Geometric interpretation for weak normality
condition, which arose earlier in the theory of dynamical systems admitting the
normal shift of hypersurfaces, is found.

</DOC>
<DOC>
<DOCNO> 117779 </DOCNO>
LiBeB Production and Associated Astrophysical Sites


  The various modes of spallative LiBeB production are summarized, and
classified according to their dependence or independence on the abundance of
medium heavy elements (CNO) illustrated by that of oxygen in the interstellar
medium.
  The predictions of the models are confronted to the available observational
correlations (Be, B vs O). Clearly, a primary mechanism should lead to a slope
one in the lg(Be/H) vs [O/H] plot and a secondary mechanism to a slope two. Due
to the ambiguity of the O data, another criterion, based on energetics, can
help us to select an adequate model. A purely secondary origin in the very
early Galaxy is much more energy demanding than a primary one. Indeed,
magnesium seems to be a possible surrogate of oxygen and iron since i) it is
spectroscopically more easy to cope with and ii) its nucleosynthetic yield is
independent of the mass cut and does not depend on metallicity.

</DOC>
<DOC>
<DOCNO> 71388 </DOCNO>
The surface brightness of dark matter: unique signatures of neutralino


  We use high resolution numerical simulations of the formation of cold dark
matter halos to simulate the background of decay products from neutralino
annihilation, such as gamma-rays or neutrinos. Halos are non-spherical, have
steep singular density profiles and contain many thousands of surviving dark
matter substructure clumps. This leads to several unique signatures in the
gamma-ray background that may be confirmed or rejected by the next generation
of gamma-ray experiments. Most importantly, the diffuse background is enhanced
by over two orders of magnitude due to annihilation within substructure halos.
The largest dark substructures are easily visibly above the background and may
account for the unidentified EGRET sources. A deep strip survey of the
gamma-ray background would allow the shape of the Galactic halo to be
quantified.

</DOC>
<DOC>
<DOCNO> 116883 </DOCNO>
High-power Circulator Test Results at 350 MHz and 700 MHz


  The high-power RF systems for the Accelerator Production of Tritium (APT)
program require high-power circulators at 350 MHz and 700 MHz to protect 1 MW
Continuous Wave (CW) klystrons from reflected power. The 350 MHz circulator is
based on the CERN, ESRF, and APS designs and has performed very well. The 700
MHz circulator is a new design. Prototype 700 MHz circulators have been
high-power tested at Los Alamos National Laboratory (LANL). The first of these
circulators has satisfied performance requirements. The circulator
requirements, results from the testing, and lessons learned from this
development are presented and discussed.

</DOC>
<DOC>
<DOCNO> 99728 </DOCNO>
Symmetrizer and Antisymmetrizer of the Birman-Wenzl-Murakami Algebras


  Explicit formulas for the symmetrizer and the antisymmetrizer of the
Birman-Wenzl-Murakami algebras BWM(r,q)_n are given.

</DOC>
<DOC>
<DOCNO> 68000 </DOCNO>
Nucleon Decay and Neutrino Properties in a Mass Model based on an SO(10)


  In this work a mass model based on a SO(10) GUT with a global U(1) family
symmetry is discussed which leads to an asymmetric Nearest Neighbour
Interaction structure for the fermionic mass matrices. As a result of the
analysis one gets three solutions of the model which include several large
left- and right-handed fermion mixings. Those mixings are not observable in the
SM where only the CKM quark mixing matrix can be measured, but they have
testable effects on the branching ratios of nucleon decays in theories beyond
the SM. One finds that decay channels with positrons in the final state are
suppressed while channels with antimuons and antineutrinos are enhanced
compared to models with small mixings. The total nucleon lifetimes obtained
should be observable by future experiments. The SO(10) model also predicts the
masses and mixings of the light neutrinos. They are in the right range to
explain the anomalies of solar and atmospheric neutrinos by means of
oscillations, preferring the small angle MSW solution for the solar neutrino
deficit.

</DOC>
<DOC>
<DOCNO> 69554 </DOCNO>
Field Correlators in Abelian-Projected Theories and Stochastic Vacuum


  The bilocal electric field strength correlators in Abelian-projected SU(2)-
and SU(3)-theories are derived with accounting for the contributions to these
quantities brought about by the virtual vortex loops, built out of the dual
Nielsen-Olesen strings. Owing to the screening of magnetic charge of the dual
vector bosons in the gas of such loops, these bosons become heavier, which
leads to the respective change of the correlation length of the vacuum in the
models under study. Besides that, it turns out that such a screening leads also
to the appearance of the long-range contribution to one of the two coefficient
functions, which parametrize the bilocal correlator within the Stochastic
Vacuum Model. Finally, the modifications of the propagators of the dual vector
bosons, inspired by the correlation effects in the gas of vortex loops, are
also discussed.

</DOC>
<DOC>
<DOCNO> 151623 </DOCNO>
Spectral functions in mathematics and physics


  This manuscript has been withdrawn by the author. For reasons please contact
Klaus Kirsten at klaus@a35.ph.man.ac.uk or kirsten@itp.uni-leipzig.de

</DOC>
<DOC>
<DOCNO> 99388 </DOCNO>
Reflexive polyhedra, weights and toric Calabi-Yau fibrations


  During the last years we have generated a large number of data related to
Calabi-Yau hypersurfaces in toric varieties which can be described by reflexive
polyhedra. We classified all reflexive polyhedra in three dimensions leading to
K3 hypersurfaces and have nearly completed the four dimensional case relevant
to Calabi-Yau threefolds. In addition, we have analysed for many of the
resulting spaces whether they allow fibration structures of the types that are
relevant in the context of superstring dualities. In this survey we want to
give background information both on how we obtained these data, which can be
found at our web site, and on how they may be used. We give a complete
exposition of our classification algorithm at a mathematical (rather than
algorithmic) level. We also describe how fibration structures manifest
themselves in terms of toric diagrams and how we managed to find the respective
data. Both for our classification scheme and for simple descriptions of
fibration structures the concept of weight systems plays an important role.

</DOC>
<DOC>
<DOCNO> 121400 </DOCNO>
Spectral Energy Distributions of T Tauri and Herbig Ae Disks: Grain


  We improve upon the radiative, hydrostatic equilibrium models of passive
circumstellar disks constructed by Chiang & Goldreich (1997). New features
include (1) account for a range of particle sizes, (2) employment of
laboratory-based optical constants of representative grain materials, and (3)
numerical solution of the equations of radiative and hydrostatic equilibrium
within the original 2-layer (disk surface + disk interior) approximation. We
explore how the spectral energy distribution (SED) of a face-on disk depends on
grain size distributions, disk geometries and surface densities, and stellar
photospheric temperatures. Observed SEDs of 3 Herbig Ae and 2 T Tauri stars,
including spectra from the Long Wavelength Spectrometer (LWS) aboard the
Infrared Space Observatory (ISO), are fitted with our models. Silicate emission
bands from optically thin, superheated disk surface layers appear in nearly all
systems. Water ice emission bands appear in LWS spectra of 2 of the coolest
stars. Infrared excesses in several sources are consistent with vertical
settling of photospheric grains. While this work furnishes further evidence
that passive reprocessing of starlight by flared disks adequately explains the
origin of infrared-to-millimeter wavelength excesses of young stars, we
emphasize how the SED alone does not provide sufficient information to
constrain particle sizes and disk masses uniquely.

</DOC>
<DOC>
<DOCNO> 121443 </DOCNO>
Energy, entropy and mass scaling relations for elliptical galaxies.


  In the present paper, we show that elliptical galaxies (Es) obey a scaling
relation between potential energy and mass. Since they are relaxed systems in a
post violent-relaxation stage, they are quasi-equilibrium gravitational systems
and therefore they also have a quasi-constant specific entropy.
  Assuming that light traces mass, these two laws imply that in the space
defined by the three S\'ersic law parameters (intensity Sigma_0, scale a and
shape nu), elliptical galaxies are distributed on two intersecting 2-manifolds:
the Entropic Surface and the Energy-Mass Surface.
  Using a sample of 132 galaxies belonging to three nearby clusters, we have
verified that ellipticals indeed follow these laws. This also implies that they
are distributed along the intersection line (the Energy-Entropy line), thus
they constitute a one-parameter family.
  These two physical laws (separately or combined), allow to find the
theoretical origin of several observed photometrical relations, such as the
correlation between absolute magnitude and effective surface brightness, and
the fact that ellipticals are located on a surface in the [log R_eff, -2.5 log
Sigma_0, log nu] space. The fact that elliptical galaxies are a one-parameter
family has important implications for cosmology and galaxy formation and
evolution models. Moreover, the Energy-Entropy line could be used as a distance
indicator.

</DOC>
<DOC>
<DOCNO> 151688 </DOCNO>
Quantum Dynamics of the Slow Rollover Transition in the Linear Delta


  We apply the linear delta expansion to the quantum mechanical version of the
slow rollover transition which is an important feature of inflationary models
of the early universe. The method, which goes beyond the Gaussian
approximation, gives results which stay close to the exact solution for longer
than previous methods. It provides a promising basis for extension to a full
field theoretic treatment.

</DOC>
<DOC>
<DOCNO> 102601 </DOCNO>
Classification of infinite dimensional weight modules over the Lie


  We give a classification of infinite dimensional indecomposable weight
modules over the Lie superalgebra $sl(2/1)$.

</DOC>
<DOC>
<DOCNO> 99482 </DOCNO>
Simulation of topological field theories by quantum computers


  Quantum computers will work by evolving a high tensor power of a small (e.g.
two) dimensional Hilbert space by local gates, which can be implemented by
applying a local Hamiltonian H for a time t. In contrast to this quantum
engineering, the most abstract reaches of theoretical physics has spawned
topological models having a finite dimensional internal state space with no
natural tensor product structure and in which the evolution of the state is
discrete, H = 0. These are called topological quantum filed theories (TQFTs).
These exotic physical systems are proved to be efficiently simulated on a
quantum computer. The conclusion is two-fold: 1. TQFTs cannot be used to define
a model of computation stronger than the usual quantum model BQP. 2. TQFTs
provide a radically different way of looking at quantum computation. The rich
mathematical structure of TQFTs might suggest a new quantum algorithm.

</DOC>
<DOC>
<DOCNO> 122622 </DOCNO>
Maximally incompressible neutron star matter


  Relativistic kinetic theory, based on the Grad method of moments as developed
by Israel and Stewart, is used to model viscous and thermal dissipation in
neutron star matter and determine an upper limit on the maximum mass of neutron
stars. In the context of kinetic theory, the equation of state must satisfy a
set of constraints in order for the equilibrium states of the fluid to be
thermodynamically stable and for perturbations from equilibrium to propagate
causally via hyperbolic equations. Application of these constraints to neutron
star matter restricts the stiffness of the most incompressible equation of
state compatible with causality to be softer than the maximally incompressible
equation of state that results from requiring the adiabatic sound speed to not
exceed the speed of light. Using three equations of state based on experimental
nucleon-nucleon scattering data and properties of light nuclei up to twice
normal nuclear energy density, and the kinetic theory maximally incompressible
equation of state at higher density, an upper limit on the maximum mass of
neutron stars averaging 2.64 solar masses is derived.

</DOC>
<DOC>
<DOCNO> 84954 </DOCNO>
On the propagation speed of wavy metric tensors


  The undulating metric tensors of general relativity do not possess a special
and common velocity of propagation. Indeed, their velocity can even coincide
with the speed of thought.

</DOC>
<DOC>
<DOCNO> 9341 </DOCNO>
Influence of the additional second neighbor hopping on the spin response


  The influence of the additional second neighbor hopping t' on the spin
response of the t-J model in the underdoped and optimally doped regimes is
studied within the fermion-spin theory. Although the additional second neighbor
hopping t' is systematically accompanied with the reduction of the dynamical
spin structure factor and susceptibility, the qualitative behavior of the
dynamical spin structure factor and susceptibility of the t-t'-J model is the
same as in the case of t-J model. The integrated dynamical spin structure
factor spectrum is almost t' independent, and the integrated dynamical spin
susceptibility still shows the particularly universal behavior as
$I(\omega,T)\propto {\rm arctan}[a_{1}\omega/T+a_{3}(\omega/T)^{3}]$.

</DOC>
<DOC>
<DOCNO> 121241 </DOCNO>
First Structure Formation: A Simulation of Small Scale Structure at High


  We describe the results of a simulation of collisionless cold dark matter in
a LambdaCDM universe to examine the properties of objects collapsing at high
redshift (z=10). We analyze the halos that form at these early times in this
simulation and find that the results are similar to those of simulations of
large scale structure formation at low redshift. In particular, we consider
halo properties such as the mass function, density profile, halo shape, spin
parameter, and angular momentum alignment with the minor axis. By understanding
the properties of small scale structure formation at high redshift, we can
better understand the nature of the first structures in the universe, such as
Population III stars.

</DOC>
<DOC>
<DOCNO> 119152 </DOCNO>
CFHT Optical PDCS Survey II: Evolution in the Space Density of Clusters


  We present the first dynamical study of the optically selected Palomar
Distant Cluster Survey (PDCS). We show that eleven out of twelve PDCS clusters
we observed are real over-densities of galaxies. Most clusters have velocity
dispersions appropriate for clusters of galaxies. However, we find a fraction
(1/3) of objects in the PDCS which have velocity dispersions in the range of
groups of galaxies (200 +/- 100 km/s) but have richnesses appropriate for
clusters of galaxies.
  We measure the richness function, X-ray luminosity function (using both the
detections and upper limits), and the mass function derived from our velocity
dispersions. We confirm that the space density, as a function of richness, of
clusters of galaxies in the PDCS is ~5 times that of the Abell catalog.
Excluding the above fraction of 1/3 of objects with low velocity dispersions,
we measure a space density ~3 times that of the Abell catalog for equivalent
mass clusters of galaxies. Our space density estimates are in agreement with
other low-redshift, optically-selected cluster surveys such as the EDCC, APM
and EDCC2, which raises the possibility that the Abell catalog is incomplete.
Our X-ray luminosity function agrees with other measurements based on both
X-ray and optically selected samples, so we find that the PDCS does not miss
clusters of galaxies that would be found in an X-ray selected survey. Our
resulting mass function, centered around 10e14 Msun/h, agrees with the
expectations from such surveys as the Canadian Network for Observational
Cosmology cluster survey, though errors on our mass measurements are too large
to constrain cosmological parameters.

</DOC>
<DOC>
<DOCNO> 68640 </DOCNO>
Neutrinoless double beta decay in four-neutrino models


  The most stringent constraint on the so-called effective electron neutrino
mass from the present neutrinoless double beta decay experiments is |M_{ee}| <
0.2 eV, while the planned next generation experiment GENIUS is anticipated to
reach a considerably more stringent limit |M_{ee}|< 0.001 eV. We investigate
the constraints these bounds set on the neutrino masses and mixings of
neutrinos in four-neutrino models where there exists a sterile neutrino along
with the three ordinary neutrinos. We find that the GENIUS experiment would be
sensitive to the electron neutrino masses down to the limit m_{\nu_e}\lsim
0.024 eV in such a scenario.

</DOC>
<DOC>
<DOCNO> 10294 </DOCNO>
Scaling behaviour of the transmission poles for Dirac comb


  The transmission poles of $N$ number of identical Dirac delta potentials
placed periodically in one-dimension are examined in the complex-energy plane.
The numerical results show that the imaginary part of the poles scales with
1/N. An approximate form of the poles is derived which supports the scaling
behaviour of the poles found numerically. It is shown that the imaginary part
of the poles are proportional to their real part for the poles close to the
ends of the bands.

</DOC>
<DOC>
<DOCNO> 121639 </DOCNO>
Compact steep-spectrum sources from the S4 sample


  We present the results of 5-GHz observations with the VLA A-array of a sample
of candidate Compact Steep Spectrum sources (CSSs) selected from the S4 survey.
We also estimate the symmetry parameters of high-luminosity CSSs selected from
different samples of radio sources, and compare these with the larger sources
of similar luminosity to understand their evolution and the consistency of the
CSSs with the unified scheme for radio galaxies and quasars. The majority of
CSSs are likely to be young sources advancing outwards through a dense
asymmetric environment. The radio properties of CSSs are found to be consistent
with the unified scheme, in which the axes of the quasars are observed close to
the line of sight, while radio galaxies are observed close to the plane of the
sky.

</DOC>
<DOC>
<DOCNO> 102550 </DOCNO>
Deformations of the trivial line bundle and vanishing theorems


  This paper reproves a general form of the Green-Lazarsfeld 'generic
vanishing' theorem and more recent strengthenings, as well as giving some new
applications.

</DOC>
<DOC>
<DOCNO> 100863 </DOCNO>
Gradient-like flows and self-indexing in stratified Morse theory


  We develop the idea of self-indexing and the technology of gradient-like
vector fields in the setting of Morse theory on a complex algebraic
stratification. Our main result is the local existence, near a Morse critical
point, of gradient-like vector fields satisfying certain ``stratified dimension
bounds up to fuzz'' for the ascending and descending sets. As a global
consequence of this, we derive the existence of self-indexing Morse functions.

</DOC>
<DOC>
<DOCNO> 122862 </DOCNO>
Neutron Star Kicks and Asymmetric Supernovae


  Observational advances over the last decade have left little doubt that
neutron stars received a large kick velocity (of order a few hundred to a
thousand km/s) at birth. The physical origin of the kicks and the related
supernova asymmetry is one of the central unsolved mysteries of supernova
research. We review the physics of different kick mechanisms, including
hydrodynamically driven, neutrino -- magnetic field driven, and
electromagnetically driven kicks. The viabilities of the different kick
mechanisms are directly related to the other key parameters characterizing
nascent neutron stars, such as the initial magnetic field and the initial spin.
Recent observational constraints on kick mechanisms are also discussed.

</DOC>
<DOC>
<DOCNO> 68042 </DOCNO>
Stabilization of internal spaces in multidimensional cosmology


  Effective 4-dimensional theories are investigated which were obtained under
dimensional reduction of multidimensional cosmological models with a minimal
coupled scalar field as matter source. Conditions for the internal space
stabilization are considered and the possibility for inflation in the external
space is discussed. The electroweak as well as the Planck fundamental scale
approaches are investigated and compared with each other. It is shown that
there exists a rescaling for the effective cosmological constant as well as for
gravitational exciton masses in the different approaches.

</DOC>
<DOC>
<DOCNO> 178558 </DOCNO>
Photoproduction of electron-positron pairs on the proton in the


  Production of lepton pairs in gamma p -> e-e+ p reaction is studied at photon
energies up to 1 GeV. We show that even if lepton charge is not measured there
are extensive kinematical regimes where the nuclear process dominates over the
Bethe-Heitler contribution. The decomposition is performed of the unpolarized
cross section for the virtual Compton scattering in terms of response
functions. These are expressed in terms of a polarization density matrix of the
virtual photon and are shown to be sensitive to the properties of baryon
resonances in the first and the second resonance regions. In the analysis a
unitary K-matrix model is used, based on an effective Lagrangian including
nucleon, mesons, and baryon resonances with masses up to 1.7 GeV. Results of
the model are compared with data for real-photon Compton scattering and
predictions are given for observables in photoproduction of lepton pairs.

</DOC>
<DOC>
<DOCNO> 10432 </DOCNO>
A potential inversion study of liquid CuBr


  Hard electromagnetic radiation diffraction experiments on copper(I)-bromide
melt are presented. Combining the result of this experiment with earlier
neutron diffraction experiments the partial pair distribution functions of CuBr
have been determined. The differing results for two of these functions obtained
recently by various techniques are discussed. A potential inversion scheme has
been applied to generate three dimensional structures from the partial pair
distribution function. The angular correlations between near neighbor atoms
have been determined. These show characteristic differences with the
glass-forming ZnCl2 melt. While in ZnCl2 melt the angle joining adjacent ZnCl4
tetrahedra has been found - as in silica glass - well defined and the +-+
(ZnClZn) angle distribution peaked the corresponding distribution function in
CuBr is broad. This is probably a key to understand, why ZnCl2 but not CuBr
melt can be easily supercooled into a glassy state.

</DOC>
<DOC>
<DOCNO> 123259 </DOCNO>
The Capture of Particles by Chaotic Resonances During Orbital Migration


  Because a chaotic zone can reduce the long timescale capture probabilities
and cause catastrophic events such as close encounters with a planet or star
during temporary capture, the dynamics of migrating planets is likely to be
strongly dependent on the widths of the resonance chaotic zones. Previous
theoretical work on the resonant capture of particles into mean-motion
resonances by orbital migration has been restricted to the study of integrable
models. By exploring toy drifting Hamiltonian models we illustrate how the
structure in phase space of a resonance can be used to generalize this
integrable capture theory to include the richer phenomenology of chaotic
resonances. We show that particles are temporarily captured into the chaotic
zone of a resonance with fixed shape for a time that is given by the width of
the chaotic zone divided by the resonance drift rate. Particles can be
permanently captured into a drifting chaotic resonance only if they are
captured into a growing integrable region. Therefore resonances containing wide
chaotic zones have lower permanent capture probabilities than those lacking
chaotic zones. We expect large deviations from the predictions of integrable
capture theories when the chaotic zone is large and the migration rate is
sufficiently long that many Lyapunov times pass while particles are temporarily
captured in the resonance. The 2:1 mean-motion resonance with Neptune in the
Kuiper Belt contains a chaotic zone, even when integrated on short timescales
such as a million years. Capture probabilities are lower than estimated
previously from drifting integrable models. This may offer an explanation for
low eccentricity Kuiper Belt objects between 45-47 AU which should have been
previously captured in the 2:1 resonance by Neptune's migration.

</DOC>
<DOC>
<DOCNO> 69874 </DOCNO>
Tests of large-Nc QCD from hadronic tau decay


  We use the Aleph data on vector and axial-vector spectral functions to test
simple duality properties of QCD in the large Nc limit, which emerge in the
approximation of a minimal hadronic ansatz of a spectrum of narrow states.
These duality properties relate the short- and long-distance behaviours of
specific correlation functions, which are order parameters of spontaneous
chiral symmetry breaking, in a way that we find well supported by the data.

</DOC>
<DOC>
<DOCNO> 170687 </DOCNO>
The Relaxation Method for Solving the Schrodinger Equation in


  The non-relativistic Schrodinger equation with the linear and Coulomb
potentials is solved numerically in configuration space using the relaxation
method. The numerical method presented in this paper is a plain explicit
Schrodinger solver which is conceptually simple and is suitable for advanced
undergraduate research.

</DOC>
<DOC>
<DOCNO> 100310 </DOCNO>
A note on a question of R. Pol concerning light maps


  Let f:X -> Y be an onto map between compact spaces such that all
point-inverses of f are zero-dimensional. Let A be the set of all functions u:X
-> I=[0,1] such that $u[f^\leftarrow(y)]$ is zero-dimensional for all y in Y.
Do almost all maps u:X -> I, in the sense of Baire category, belong to A? H.
Toru\'nczyk proved that the answer is yes if Y is countable-dimensional. We
extend this result to the case when Y has property C.

</DOC>
<DOC>
<DOCNO> 67933 </DOCNO>
Physics Needs for Future Accelerators


  Contents:
 1. Prologomena to any meta future physics
   1.1 Physics needs for building future accelerators
   1.2 Physics needs for funding future accelerators
 2. Physics questions for future accelerators
   2.1 Crimes and misapprehensions
     2.1.1 Organized religion  2.1.2 Feudalism  2.1.3 Trotsky was right
   2.2 The Standard Model as an effective field theory
   2.3 What is the scale of new physics?
   2.4 What could be out there?
   2.5 Model-independent conclusions
 3. Future accelerators
   3.1 What is the physics driving the LHC?
   3.2 What is the physics driving the LC?
     3.2.1 Higgs physics is golden
     3.2.2 LHC won't be sufficient to unravel the new physics as the TeV scale
     3.2.3 LC precision measurements can pin down new physics scales
   3.3 Why a Neutrino Factory?
   3.4 Pushing the energy frontier

</DOC>
<DOC>
<DOCNO> 120631 </DOCNO>
The combination of ground-based astrometric compilation catalogues with


  The combination of ground-based astrometric compilation catalogues, such as
the FK5 or the GC, with the results of the ESA Astrometric Satellite HIPPARCOS
produces for many thousands of stars proper motions which are significantly
more accurate than the proper motions derived from the HIPPARCOS observations
alone. In Paper I (Wielen et al. 1999, A&A 347, 1046) we have presented a
method of combination for single stars (SI mode). The present Paper II derives
a combination method which is appropriate for an ensemble of 'apparently
single-stars' which contains undetected astrometric binaries. In this case the
quasi-instantaneously measured HIPPARCOS proper motions and positions are
affected by 'cosmic errors', caused by the orbital motions of the photo-centers
of the undetected binaries with respect to their center-of-mass. In contrast,
the ground-based data are 'mean values' obtained from a long period of
observation. We derive a linear 'long-term prediction' (LTP mode) for epochs
far from the HIPPARCOS epoch T_H ~ 1991.25, and a linear 'short-term
prediction' (STP mode) for epochs close to T_H. The most accurate prediction
for a position at an arbitrary epoch is provided by a smooth, non-linear
transition from the STP solution to the LTP solution. We present an example for
the application of our method, and we discuss the error budget of our method
for the FK6 (a combination of the FK5 with HIPPARCOS) and for the combination
catalog GC+HIP. For the basic fundamental stars, the accuracy of the FK6 proper
motions in the LTP mode is better than that of the HIPPARCOS proper motions
(taking here the cosmic errors into account) by a factor of more than 4.

</DOC>
<DOC>
<DOCNO> 99363 </DOCNO>
The Boltzmann/Shannon entropy as a measure of correlation


  IIt is demonstrated that the entropy of statistical mechanics and of
information theory, $S({\bf p}) = -\sum p_i \log p_i $ may be viewed as a
measure of correlation. Given a probability distribution on two discrete
variables, $p_{ij}$, we define the correlation-destroying transformation $C:
p_{ij} \to \pi_{ij}$, which creates a new distribution on those same variables
in which no correlation exists between the variables, i.e. $\pi_{ij} = P_i
Q_j$. It is then shown that the entropy obeys the relation $S({\bf p}) \leq
S({\bf \pi}) = S({\bf P}) + S({\bf Q})$, i.e. the entropy is non-decreasing
under these correlation-destroying transformations.

</DOC>
<DOC>
<DOCNO> 71198 </DOCNO>
Two-Brane Models and BBN


  We obtain a class of solutions for the AdS$_5$ two-brane models by imposing
the observed value of cosmological constant and Newton coupling constant on the
visible brane. When all terms up to the first order of matter density are
included, the cosmological evolution on the observable brane depends on the
equation of state of the matter and consequently when the pressure exists, the
cosmology of these models deviates from FLRW cosmology. We show that it is
possible to choose the matter equation of state on the hidden brane to
neutralize its contribution on the cosmological evolution of the visible brane.
We compare the prediction of these models for primordial {\it $^4$He} yield
with observations. In standard BBN with $n_{\nu}^{light} = 3$ this brane model
is ruled out. If in addition to 3 SM neutrinos there is one light sterile
neutrino, this model reconciles the observed {\it $^4$He} yield with a high
${\Omega}_b \sim 0.033 h^{-2}$ suggested by BOOMERANG and MAXIMA experiments.

</DOC>
<DOC>
<DOCNO> 121749 </DOCNO>
The Optical Gravitational Lensing Experiment. BVI Maps of Dense Stellar


  We present the BVI photometric maps of the Large Magellanic Cloud. They
contain BVI photometry and astrometry of more than 7 million stars from the
central parts of the LMC. The data were collected during the second phase of
the OGLE microlensing project. We discuss the accuracy of the data and present
color-magnitude diagrams of all 26 fields observed by OGLE in the LMC.
  The BVI maps of the LMC are accessible electronically for the astronomical
community from the OGLE Internet archive.

</DOC>
<DOC>
<DOCNO> 39843 </DOCNO>
Large N_c, chiral approach to M_eta' at finite temperature


  We study the temperature dependence of the eta and eta' meson masses within
the framework of U(3)_L x U(3)_R chiral perturbation theory, up to
next-to-leading order in a simultaneous expansion in momenta, quark masses and
number of colours. We find that both masses decrease at low temperatures, but
only very slightly. We analyze higher order corrections and argue that large
N_c suggests a discontinuous drop of M_eta' at the critical temperature of
deconfinement T_c, consistent with a first order transition to a phase with
approximate U(1)_A symmetry.

</DOC>
<DOC>
<DOCNO> 169717 </DOCNO>
Eigenvalues, Peres' separability condition and entanglement


  The general expression with the physical significance and positive definite
condition of the eigenvalues of $4\times 4$ Hermitian and trace-one matrix are
obtained. This implies that the eigenvalue problem of the $4\times 4$ density
matrix is generally solved. The obvious expression of Peres' separability
condition for an arbitrary state of two qubits is then given out and it is very
easy to use. Furthermore, we discuss some applications to the calculation of
the entanglement, the upper bound of the entanglement, and a model of the
transfer of entanglement in a qubit chain through a noisy channel.

</DOC>
<DOC>
<DOCNO> 40552 </DOCNO>
A Quasi-Model-Independent Search for New High p_T Physics at DZero


  We apply a quasi-model-independent strategy ("Sleuth") to search for new high
p_T physics in approximately 100 pb^-1 of ppbar collisions at sqrt(s) = 1.8 TeV
collected by the DZero experiment during 1992-1996 at the Fermilab Tevatron. We
systematically analyze many exclusive final states and demonstrate sensitivity
to a variety of models predicting new phenomena at the electroweak scale. No
evidence of new high p_T physics is observed.

</DOC>
<DOC>
<DOCNO> 14123 </DOCNO>
Testing Broken U(1) Symmetry in a Two-Component Atomic Bose-Einstein


  We present a scheme for determining if the quantum state of a small trapped
Bose-Einstein condensate is a state with well defined number of atoms, a Fock
state, or a state with a broken U(1) gauge symmetry, a coherent state. The
proposal is based on the observation of Ramsey fringes. The population
difference observed in a Ramsey fringe experiment will exhibit collapse and
revivals due to the mean-field interactions. The collapse and revival times
depend on the relative strength of the mean-field interactions for the two
components and the initial quantum state of the condensate.

</DOC>
<DOC>
<DOCNO> 170764 </DOCNO>
Effects of Imperfect Gate Operations in Shor's Prime Factorization


  The effects of imperfect gate operations in implementation of Shor's prime
factorization algorithm are investigated. The gate imperfections may be
classified into three categories: the systematic error, the random error, and
the one with combined errors. It is found that Shor's algorithm is robust
against the systematic errors but is vulnerable to the random errors. Error
threshold is given to the algorithm for a given number $N$ to be factorized.

</DOC>
<DOC>
<DOCNO> 122836 </DOCNO>
Planetary dynamics in stellar clusters


  We investigate how the formation and evolution of extrasolar planetary
systems can be affected by stellar encounters that occur in the crowded
conditions of a stellar cluster. Using plausible estimates of cluster
evolution, we show how planet formation may be supressed in globular clusters
while planets wider than 0.1 AU that do form in such environments can be
ejected from their stellar system. Less crowded systems such as open clusters
have a much reduced effect on any planetary system. Planet formation is
unaffected in open clusters and only the wider planetary systems will be
disrupted during the cluster's lifetime. The potential for free-floating
planets in these environments is also discussed.

</DOC>
<DOC>
<DOCNO> 116779 </DOCNO>
Polarization Elements-A Group Theoretical Study


  The Classification of Polarization elements, the polarization affecting
optical devices which have a Jones matrix representation, according to the
types of eigenvectors they possess, is given a new visit through the
Group-theoretical connection of polarization elements. The diattenuators and
retarders are recognized as the elements corresponding to boosts and rotations
respectively. The structure of homogeneous elements other than diattenuators
and retarders are identified by giving the quaternion corresponding to these
elements. The set of degenerate polarization elements is identified with the so
called `null' elements of the Lorentz Group. Singular polarization elements are
examined in their more illustrative Mueller matrix representation and finally
the eigenstructure of a special class of singular Mueller matrices is studied.

</DOC>
<DOC>
<DOCNO> 170167 </DOCNO>
Can quantum computer perform better than classical?


  A theoretical model of a quantum device which can factorize any number N in
two steps i.e. by preparing an input state and performing a measurement is
discussed. The analysis reveals that the duration of state preparation and
measurement is proportional to N while the energy consumption grows like log N.
These results suggest the existence of Heisenberg-type relation putting limits
on the efficiency of a quantum computer in terms of a total computation time, a
total energy consumption and a classical complexity of the problem.

</DOC>
<DOC>
<DOCNO> 39891 </DOCNO>
Track Fit Hypothesis Testing and Kink Selection using Sequential


  Deviations between the form of trajectory assumed in a fit to a set of
measurements and the actual form of the trajectory can give rise to sequential
correlations in the residuals from the fit. These correlations can provide a
more powerful goodness-of-fit test than that based on the minimum chi-square
from a least squares fit. The use of this additional information is explored in
the context of several common trajectory errors (e.g. decays in flight)
encountered in charged particle tracking.

</DOC>
<DOC>
<DOCNO> 10031 </DOCNO>
Magnetic, thermal, and transport properties on single crystals of


  Magnetization, heat capacity, electrical resistivity, thermoelectric power,
and Hall effect have been investigated on single-crystalline Ce_2PdSi_3. This
compound is shown to order antiferromagnetically below N'eel temperature (T_N)
\~ 3 K. The Sommerfeld coefficient far below T_N is found to be about 110 mJ/K^2
mol Ce, which indicates the heavy-fermion character of this compound. The
transport and magnetic properties exhibit large anisotropy with an interplay
between crystalline-electric-field (CEF) and Kondo effects. The sign of
thermoelectric power is opposite for different directions at high temperatures
and the ordinary Hall coefficient is anisotropic with opposite sign for
different geometries, indicating the anisotropic Fermi surface. The CEF
analysis from the temperature dependence of magnetic susceptibility suggests
that the ground state is |+/-1/2>. The first and the second excited CEF doublet
levels are found to be located at about 30 and 130 K, respectively. The Kondo
temperature is estimated to be the same order as T_N, indicating the presence
of a delicate competition between the Kondo effect and magnetic order.

</DOC>
<DOC>
<DOCNO> 70019 </DOCNO>
Chiral QCD: Baryon dynamics


  I review the consequences of the chiral symmetry of QCD for the structure and
dynamics of the low-lying baryons, with particular emphasis on the nucleon.

</DOC>
<DOC>
<DOCNO> 8950 </DOCNO>
Electronic structure and ferroelectricity in SrBi2Ta2O9


  The electronic structure of SrBi2Ta2O9 is investigated from first-principles,
within the local density approximation, using the full-potential linearized
augmented plane wave (LAPW) method. The results show that, besides the large
Ta(5d)-O(2p) hybridization which is a common feature of the ferroelectric
perovskites, there is an important hybridization between bismuth and oxygen
states. The underlying static potential for the ferroelectric distortion and
the primary source for ferroelectricity is investigated by a lattice-dynamics
study using the Frozen Phonon approach.

</DOC>
<DOC>
<DOCNO> 80878 </DOCNO>
Some universal properties of the string breaking


  In gauge systems coupled to matter, the static potential flattens out at a
scale where the confining string breaks by formation of a dynamical pair of
particles. Surprisingly, such a breaking is invisible in Wilson loops even when
the inter-charge separation is much larger than the flattening scale. Observing
string breaking also requires using different operators. A known string
mechanism provides us with a simple explanation, leading to the area law for
large Wilson loops, as observed in most gauge models coupled to whatever kind
of matter. It is also pointed out that in a simple 3D Z_2 gauge-Higgs model,
once reformulated in terms of Fortuin Kasteleyn clusters, this peculiar
behaviour of the Wilson operator can be ascribed to non-trivial linking of a
percolating cluster to the Wilson loop. Some numerical tests on this model are
also presented.

</DOC>
<DOC>
<DOCNO> 71619 </DOCNO>
Non-lattice determinations of the light quark masses


  The sum rule determinations of m_s and the chiral perturbation theory results
for the ratios m_u/m_d and m_s/m_d are reviewed and a method for the
extrapolation of lattice data to the physical values of m_u and m_d is
outlined.

</DOC>
<DOC>
<DOCNO> 150508 </DOCNO>
Superdualities: Below and beyond U-duality


  Hidden symmetries are the backbone of Integrable two-dimensional theories.
They provide classical solutions of higher dimensional models as well, they
seem to survive partially quantisation and their discrete remnants in M-theory
called U-dualities, would provide a way to control infinities and
nonperturbative effects in Supergravities and String theories. Starting from
Einstein gravity we discuss the building blocks of these large groups of
internal symmetries, and embed them in superalgebras of dynamical symmetries.
The classical field equations for all bosonic matter fields of all toroidally
compactified supergravities are invariant under such ``superdualities''.
Possible extensions are briefly discussed.

</DOC>
<DOC>
<DOCNO> 152382 </DOCNO>
Gaussian and Mean Field Approximations for Reduced Yang-Mills Integrals


  In this paper, we consider bosonic reduced Yang-Mills integrals by using some
approximation schemes, which are a kind of mean field approximation called
Gaussian approximation and its improved version. We calculate the free energy
and the expectation values of various operators including Polyakov loop and
Wilson loop. Our results nicely match to the exact and the numerical results
obtained before. Quite good scaling behaviors of the Polyakov loop and of the
Wilson loop can be seen under the 't Hooft like large $N$ limit for the case of
the loop length smaller. Then, simple analytic expressions for the loops are
obtained. Furthermore, we compute the Polyakov loop and the Wilson loop for the
case of the loop length sufficiently large, where with respect to the Polyakov
loop there seems to be no known results in appropriate literatures even in
numerical calculations. The result of the Wilson loop exhibits a strong
resemblance to the result simulated for a few smaller values of $N$ in the
supersymmetric case.

</DOC>
<DOC>
<DOCNO> 10975 </DOCNO>
Replica symmetry breaking in the minority game


  We extend and complete recent work concerning the analytic solution of the
minority game. Nash equilibria (NE) of the game have been found to be related
to the ground states of a disordered hamiltonian with replica symmetry breaking
(RSB), signalling the presence of a large number of them. Here we study the
number of NE both analytically and numerically. We then analyze the stability
of the recently-obtained replica-symmetric (RS) solution and, in the region
where it becomes unstable, derive the solution within one-step RSB
approximation. We are finally able to draw a detailed phase diagram of the
model.

</DOC>
<DOC>
<DOCNO> 70609 </DOCNO>
Regularisation : many recipes, but a unique principle : Ward identities


  We analyse the recent controversy on a possible Chern-Simons like term
generated through radiative corrections in QED with a CPT violating term : we
prove that, if the theory is correctly defined through Ward identities and
normalisation conditions, no Chern-Simons term appears, without any ambiguity.
This is related to the fact that such a term is a kind of minor modification of
the gauge fixing term, and then no renormalised. The past year literature on
that subject is discussed, and we insist on the fact that any absence of an
{\sl a priori} divergence should be explained by some symmetry or some
non-renormalisation theorem.

</DOC>
<DOC>
<DOCNO> 84654 </DOCNO>
Black hole evolution by spectral methods


  Current methods of evolving a spacetime containing one or more black holes
are plagued by instabilities that prohibit long-term evolution. Some of these
instabilities may be due to the numerical method used, traditionally finite
differencing. In this paper, we explore the use of a pseudospectral collocation
(PSC) method for the evolution of a spherically symmetric black hole spacetime
in one dimension using a hyperbolic formulation of Einstein's equations. We
demonstrate that our PSC method is able to evolve a spherically symmetric black
hole spacetime forever without enforcing constraints, even if we add dynamics
via a Klein-Gordon scalar field. We find that, in contrast to
finite-differencing methods, black hole excision is a trivial operation using
PSC applied to a hyperbolic formulation of Einstein's equations. We discuss the
extension of this method to three spatial dimensions.

</DOC>
<DOC>
<DOCNO> 10454 </DOCNO>
The first 20 minutes in the Hong Kong stock market


  Based on the minute-by-minute data of the Hang Seng Index in Hong Kong and
the analysis of probability distribution and autocorrelations, we find that the
index fluctuations for the first few minutes of daily opening show behaviors
very different from those of the other times. In particular, the properties of
tail distribution, which will show the power law scaling with exponent about -4
or an exponential-type decay, the volatility, and its correlations depend on
the opening effect of each trading day.

</DOC>
<DOC>
<DOCNO> 80730 </DOCNO>
A lattice path integral for supersymmetric quantum mechanics


  We report on a study of the supersymmetric anharmonic oscillator computed
using a euclidean lattice path integral. Our numerical work utilizes a Fourier
accelerated hybrid Monte Carlo scheme to sample the path integral. Using this
we are able to measure massgaps and check Ward identities to a precision of
better than one percent. We work with a non-standard lattice action which we
show has an {\it exact} supersymmetry for arbitrary lattice spacing in the
limit of zero interaction coupling. For the interacting model we show that
supersymmetry is restored in the continuum limit without fine tuning. This is
contrasted with the situation in which a `standard' lattice action is employed.
In this case supersymmetry is not restored even in the limit of zero lattice
spacing. Finally, we show how a minor modification of our action leads to an
{\it exact}, local lattice supersymmetry even in the presence of interaction.

</DOC>
<DOC>
<DOCNO> 152616 </DOCNO>
Projector Equivalences in K theory and Families of Non-commutative


  Projector equivalences used in the definition of the K-theory of operator
algebras are shown to lead to generalizations of the solution generating
technique for solitons in NC field theories, which has recently been used in
the construction of branes from other branes in B-field backgrounds and in the
construction of fluxon solutions of gauge theories. The generalizations involve
families of static solutions as well as solutions which depend on euclidean
time and interpolate between different configurations. We investigate the
physics of these generalizations in the brane-construction as well as the
fluxon context. These results can be interpreted in the light of recent
discussions on the topology of the configuration space of string fields.

</DOC>
<DOC>
<DOCNO> 178708 </DOCNO>
Theoretical description of deformed proton emitters: nonadiabatic


  The newly developed nonadiabatic method based on the coupled-channel
Schroedinger equation with Gamow states is used to study the phenomenon of
proton radioactivity. The new method, adopting the weak coupling regime of the
particle-plus-rotor model, allows for the inclusion of excitations in the
daughter nucleus. This can lead to rather different predictions for lifetimes
and branching ratios as compared to the standard adiabatic approximation
corresponding to the strong coupling scheme. Calculations are performed for
several experimentally seen, non-spherical nuclei beyond the proton dripline.
By comparing theory and experiment, we are able to characterize the angular
momentum content of the observed narrow resonance.

</DOC>
<DOC>
<DOCNO> 119269 </DOCNO>
The Spin Period, Luminosity and Age Distributions of Anomalous X-Ray


  We consider the accretion model for anomalous X-ray pulsars proposed recently
by Chatterjee, Hernquist and Narayan, in which the emission is powered by
accretion from a fossil disk formed by the fallback of material from a
supernova explosion. We demonstrate that this model is able to account for the
spin period, luminosity and age distributions of the observed population of
AXPs for reasonable and broad distributions of the free parameters of the
model, namely, the surface magnetic field of the neutron star, the mass of its
accretion disk and its initial spin period. In particular, this model is able
statistically to account for the puzzlingly narrow observed spin distribution
of the AXPs. We show also that if the establishment of fallback accretion disks
around isolated neutron stars is a universal phenomenon, then a fairly large
minority ($\sim 20%$) of these objects become X-ray bright AXPs or X-ray faint
systems spinning down by propeller action, while the rest become radio pulsars.

</DOC>
<DOC>
<DOCNO> 8716 </DOCNO>
Possible critical point in phase diagrams of interlayer Josephson-vortex


  A critical value in the product of the anisotropy parameter and the magnetic
field is observed in interlayer Josephson-vortex systems by extensive Monte
Carlo simulations. Below/above this critical value the thermodynamic phase
transition between the normal and the superconducting states upon temperature
sweeping is first/second order. The origin is the intrinsic pinning effect of
the layered structure of high-Tc superconductors.

</DOC>
<DOC>
<DOCNO> 68952 </DOCNO>
Bread and Butter Standard Model


  Lectures given at the International School of Subnuclear Physics: 37th
Course: Basics and Highlights of Fundamental Physics, Erice, Italy, 29 Aug - 7
Sep 1999.

</DOC>
<DOC>
<DOCNO> 8695 </DOCNO>
Phonon-mediated drag at $\nu=1/2$: A test of the Chern-Simons composite


  We report on a study of the phonon-mediated frictional drag between
two-dimensional electron layers at the Landau level filling factor $\nu=1/2$
predicted by Chern-Simons composite-fermion theory. Frictional drag between
widely spaced layers is dominated by the phonon-mediated interaction and is
altered from its zero-field form because of the large composite-fermion
effective mass and, less strongly, by magnetic local-field effects. We find
that the reduced drag resistance $\rho(T)/T^2$ peaks at a larger temperature
and has a different density dependence than at zero field. We compare these
results with recent experimental findings.

</DOC>
<DOC>
<DOCNO> 123025 </DOCNO>
Helium-like ions as powerful X-ray plasma diagnostics


  We revisited the calculations of the ratios of the Helium-like ion
``triplet'' (resonance, intercombination, and forbidden lines) for Z=6 to 14 (C
V, N VI, O VII, Ne IX, Mg XI, Si XIII) in order to provide temperature, density
and ionization diagnostics for the new high-resolution spectroscopic data of
Chandra and XMM-Newton. Comparing to earlier computations, collisional rates
are updated and the best experimental values for radiative transition
probabilities are used. The influence of an external radiation field
(photo-excitation) and the contribution from unresolved dielectronic satellite
lines to the line ratios are discussed. Collision-dominated plasmas (e.g.
stellar coronae), photo-ionized plasmas (e.g. AGNs) or transient plasmas (e.g.
SNRs) are considered.

</DOC>
<DOC>
<DOCNO> 12390 </DOCNO>
Small-World Networks: Links with long-tailed distributions


  Small-world networks (SWN), obtained by randomly adding to a regular
structure additional links (AL), are of current interest. In this article we
explore (based on physical models) a new variant of SWN, in which the
probability of realizing an AL depends on the chemical distance between the
connected sites. We assume a power-law probability distribution and study
random walkers on the network, focussing especially on their probability of
being at the origin. We connect the results to L\'evy Flights, which follow
from a mean field variant of our model.

</DOC>
<DOC>
<DOCNO> 116419 </DOCNO>
Limits on the Applicability of Classical Electromagnetic Fields as


  Can the wavelength of a classical electromagnetic field be arbitrarily small,
or its electric field strength be arbitrarily large? If we require that the
radiation-reaction force on a charged particle in response to an applied field
be smaller than the Lorentz force we find limits on the classical
electromagnetic field that herald the need for a better theory, i.e., one in
better accord with experiment. The classical limitations find ready
interpretation in quantum electrodynamics. The examples of Compton scattering
and the QED critical field strength are discussed. It is still open to
conjecture whether the present theory of QED is valid at field strengths beyond
the critical field revealed by a semiclassical argument.

</DOC>
<DOC>
<DOCNO> 119914 </DOCNO>
Clues to Quasar Broad Line Region Geometry and Kinematics


  We present evidence that the high-velocity CIV lambda 1549 emission line gas
of radio-loud quasars may originate in a disk-like configuration, in close
proximity to the accretion disk often assumed to emit the low-ionization lines.
For a sample of 36 radio-loud z~2 quasars we find the 20--30% peak width to
show significant inverse correlations with the fractional radio core-flux
density, R, the radio axis inclination indicator. Highly inclined systems have
broader line wings, consistent with a high-velocity field perpendicular to the
radio axis. By contrast, the narrow line-core shows no such relation with R, so
the lowest velocity CIV-emitting gas has an inclination independent velocity
field. We propose that this low-velocity gas is located at higher
disk-altitudes than the high-velocity gas. A planar origin of the high-velocity
CIV-emission is consistent with the current results and with an accretion
disk-wind emitting the broad lines. A spherical distribution of randomly
orbiting broad-line clouds and a polar high-ionization outflow are ruled out.

</DOC>
<DOC>
<DOCNO> 67883 </DOCNO>
Dispersion Relation Analyses of Pion Form Factor, Chiral Perturbation


  The Vector Pion form factor below 1 GeV is analyzed using experimental data
on its modulus, the P-wave pion pion phase shifts and dispersion relation. It
is found that causality is satisfied. Using dispersion relation, terms
proportional to s squared and s cubed are calculated using the experimental
data, where s is the momentum transfer. They are much larger than the one-loop
and two-loop Chiral Perturbation Theory calculations. Unitarized model
calculations agree very well with dispersion relation results.

</DOC>
<DOC>
<DOCNO> 40242 </DOCNO>
Four Pion Final States with Tagged Photons at Electron Positron


  A Monte Carlo generator has been constructed to simulate the reaction e^+e^-
\to \gamma + 4 \pi, where the photon is assumed to be observed in the detector.
Only initial state radiation is considered. Additional collinear photon
radiation has been incorporated with the technique of structure functions.
Predictions are presented for cms energies of 1GeV, 3GeV and 10GeV,
corresponding to the energies of DAPHNE, BEBC and of B-meson factories. The
event rates are sufficiently high to allow for a precise measurement of R(Q^2)
in the region of Q between approximately 1GeV and 2.5GeV. For the construction
of the program we employ isospin relations between the amplitudes governing tau
decays into four pions and electron positron annihilation into four pions.
Estimates of the kinematic breaking of these isospin relations as a consequence
of the \pi^- -- \pi^0 mass difference are given.

</DOC>
<DOC>
<DOCNO> 117980 </DOCNO>
Research and Education in Basic Space Science: The Approach Pursued in


  Since 1990, the United Nations in cooperation with the European Space Agency
is holding annually a workshop on basic space science for the benefit of the
worldwide development of astronomy. These workshops have been held in countries
of Asia and the Pacific (India, Sri Lanka), Latin America and the Caribbean
(Costa Rica, Colombia, Honduras), Africa (Nigeria), Western Asia (Egypt,
Jordan), and Europe (Germany, France). Additional to the scientific benefits of
the workshops and the strengthening of international cooperation, the workshops
lead to the establishment of astronomical telescope facilities in Colombia,
Egypt, Honduras, Jordan, Morocco, Paraguay, Peru, Philippines, Sri Lanka, and
Uruguay. The annual UN/ESA Workshops continue to pursue an agenda to network
these astronomical telescope facilities through similar research and education
programmes. Teaching material and hands-on astrophysics material has been
developed for the operation of such astronomical telescope facilities in an
university environment.

</DOC>
<DOC>
<DOCNO> 120752 </DOCNO>
Analysis of cosmic microwave background data on an incomplete sky


  Measurement of the angular power spectrum of the cosmic microwave background
is most often based on a spherical harmonic analysis of the observed
temperature anisotropies. Even if all-sky maps are obtained, however, it is
likely that the region around the Galactic plane will have to be removed due to
its strong microwave emissions. The spherical harmonics are not orthogonal on
the cut sky, but an orthonormal basis set can be constructed from a linear
combination of the original functions. Previous implementations of this
technique, based on Gram-Schmidt orthogonalisation, were limited to maximum
Legendre multipoles of l_max < 50 as they required all the modes have
appreciable support on the cut sky, whereas for large l_max the fraction of
modes supported is equal to the fractional area of the region retained. This
problem is solved by using a singular value decomposition to remove the
poorly-supported basis functions, although the treatment of the
non-cosmological monopole and dipole modes necessarily becomes more
complicated. A further difficulty is posed by computational limitations --
orthogonalisation for a general cut requires O(l_max^6) operations and
O(l_max^4) storage and so is impractical for l_max > 200 at present. These
problems are circumvented for the special case of constant (Galactic) latitude
cuts, for which the storage requirements scale as O(l_max) and the operations
count scales as O(l_max^4). Less clear, however, is the stage of the data
analysis at which the cut is best applied. As convolution is ill-defined on the
incomplete sphere, beam-deconvolution should not be performed after the cut,
and, if all-sky component separation is as successful as simulations indicate,
the Galactic plane should probably be removed immediately prior to power
spectrum estimation.

</DOC>
<DOC>
<DOCNO> 99915 </DOCNO>
Coherent and Squeezed States in Shape Invariant Potentials Obtained from


  A general algorithm has been given for the generation of Coherent and
Squeezed states, in one-dimensional hamiltonians with shape invariant
potential, obtained from the master function. The minimum uncertainty states of
these potentials are expressed in terms of the well-known special functions.

</DOC>
<DOC>
<DOCNO> 84849 </DOCNO>
The cubic matrix model and a duality between strings and loops


  We find evidence for a duality between the standard matrix formulations of M
theory and a background independent theory which extends loop quantum gravity
by replacing SU(2) with a supersymmetric and quantum group extension of SU(16).
This is deduced from the recently proposed cubic matrix model for M theory
which has been argued to have compactifications which reduce to the IKKT and
dWHN-BFSS matrix models. Here we find new compactifications of this theory
whose Hilbert spaces consist of SU(16) conformal blocks on compact
two-surfaces. These compactifications break the SU(N) symmetry of the standard
M theory compactifications, while preserving SU(16), while the BFSS model
preserve the SU(N) but break SU(16) to the SO(9) symmetry of the 11 dimensional
light cone coordinates. These results suggest that the supersymmetric and
quantum deformed SU(16) extension of loop quantum gravity provides a dual,
background independent description of the degrees of freedom and dynamics of
the M theory matrix models.

</DOC>
<DOC>
<DOCNO> 100152 </DOCNO>
Operads and algebraic homotopy


  This paper proves that the homotopy type of a pointed, simply-connected,
2-reduced simplicial set is determined by the chain-complex augmented by
functorial diagonal and higher diagonal maps (a simple generalization of the
ones used to define Steenrod operations). The treatment of this problem is
completely self-contained, and includes material that simplifies, extends, and
corrects material from the authors AMS Memoir, "Iterating the cobar
construction".

</DOC>
<DOC>
<DOCNO> 9038 </DOCNO>
The Viscous Slowing Down of Supercooled Liquids and the Glass


  The viscous slowing down of supercooled liquids that leads to glass formation
can be considered as a classical, and is assuredly a thoroughly studied,
example of a "jamming process". In this review, we stress the distinctive
features characterizing the phenomenon. We also discuss the main theoretical
approaches, with an emphasis on the concepts (free volume, dynamic freezing and
mode-coupling approximations, configurational entropy and energy landscape,
frustration) that could be useful in other areas of physics where jamming
processes are encountered.

</DOC>
<DOC>
<DOCNO> 118512 </DOCNO>
Modelling the Infrared continuum of Centaurus A


  We present ISOPHOT_S, ISOSWS and 8 to 13 micron ground based observations of
Centaurus A that show prominent PAH and silicate features. These and other data
are used to construct a model for the infrared continuum. We find that in a
nuclear sized aperture (~4 arcsec, ~60 pc) the SED is characteristic of
emission from a starburst and AGN torus; in larger apertures an additional
component of cirrus emission is required. Based on our model, the torus
diameter is estimated to be 3.6 pc and the best fitting inclination angle of
the torus is 45 degrees. This result has implications for the detectability of
tori in low power AGN and in particular for the use of the IRAS 60/25 micron
flux ratio as an indicator of the torus inclination.

</DOC>
<DOC>
<DOCNO> 12692 </DOCNO>
Critical currents, flux-creep activation energy and potential barriers


  We present an experimental study of thermally activated flux creep in a
superconducting ring-shaped epitaxial YBCO film as well as a new way of
analyzing the experimental data. The measurements were made in a wide range of
temperatures between 10 and 83 K. The upper temperature limit was dictated by
our experimental technique and at low temperatures we were limited by a
crossover to quantum tunneling of vortices. It is shown that the experimental
data can very well be described by assuming a simple thermally activated
hopping of vortices or vortex bundles over potential barriers, whereby the
hopping flux objects remain the same for all currents and temperatures. The new
procedure of data analysis also allows to establish the current and temperature
dependencies of the flux-creep activation energy U, as well as the temperature
dependence of the critical current Ic, from the flux-creep rates measured at
different temperatures. The variation of the activation energy with current,
U(I/Ic), is then used to reconstruct the profile of the potential barriers in
real space.

</DOC>
<DOC>
<DOCNO> 122675 </DOCNO>
Resistive Magnetohydrodynamics of Jet Formation and Magnetically Driven


  We carried out 2.5-dimensional resistive magnetohydrodynamic simulations to
study the effects of magnetic diffusivity on magnetically driven mass accretion
and jet formation. We found that (1) when the normalized magnetic diffusivity,
is small, mass accretion and jet formation take place intermittently; (2) when
diffusivity is middle, the system evolves toward a quasi-steady state; and the
system evolves toward a quasi-steady state; and (3) when diffusivity is large,
the accretion/mass outflow rate decreases with diffusivity and approaches 0.
The results of these simulations indicate magnetic braking provide a mass
accretion rate which is sufficient to explain the activity of AGNs.

</DOC>
<DOC>
<DOCNO> 117810 </DOCNO>
ROSAC: Studying the clustering properties of X-ray selected AGNs


  We present the first ROSAC results of an AGN clustering analysis. This study
comprises a sample of 200 AGNs, 75% of which being at low redshifts z<0.5, in
the Ursa Major constellation. The spatial 2-point-correlation function (SCF) as
well as the minimal spanning tree (MST) technique were applied. Some evidence
for clustering is found in the SCF, although with low significance. Using the
MST technique, we could find two AGN groups. This result is preliminary and the
exact significance will be tested with careful simulations.

</DOC>
<DOC>
<DOCNO> 151634 </DOCNO>
Loop Variables and Gauge Invariant Interactions - II


  We continue the discussion of our previous paper on writing down gauge
invariant interacting equations for a bosonic string using the loop variable
approach. In the earlier paper the equations were written down in one higher
dimension where the fields are massless. In this paper we describe a procedure
for dimensional reduction that gives interacting equations for fields with the
same spectrum as in bosonic string theory. We also argue that the on-shell
scattering amplitudes implied by these equations for the physical modes are the
same as for the bosonic string. We check this explicitly for some of the
simpler equations. The gauge transformation of space-time fields induced by
gauge transformations of the loop variables are discussed in some detail. The
unintegrated (i.e. before the Koba-Nielsen integration), regularized version of
the equations, are gauge invariant off-shell (i.e. off the {\em free} mass
shell).

</DOC>
<DOC>
<DOCNO> 13070 </DOCNO>
Equilibrium crystal shapes in the Potts model


  The three-dimensional $q$-state Potts model, forced into coexistence by
fixing the density of one state, is studied for $q=2$, 3, 4, and 6. As a
function of temperature and number of states, we studied the resulting
equilibrium droplet shapes. A theoretical discussion is given of the interface
properties at large values of $q$. We found a roughening transition for each of
the numbers of states we studied, at temperatures that decrease with increasing
$q$, but increase when measured as a fraction of the melting temperature. We
also found equilibrium shapes closely approaching a sphere near the melting
point, even though the three-dimensional Potts model with three or more states
does not have a phase transition with a diverging length scale at the melting
point.

</DOC>
<DOC>
<DOCNO> 69796 </DOCNO>
From computation to black holes and space-time foam


  We show that quantum mechanics and general relativity limit the speed
$\tilde{\nu}$ of a simple computer (such as a black hole) and its memory space
$I$ to $\tilde{\nu}^2 I^{-1} \lsim t_P^{-2}$, where $t_P$ is the Planck time.
We also show that the life-time of a simple clock and its precision are
similarly limited. These bounds and the holographic bound originate from the
same physics that governs the quantum fluctuations of space-time. We further
show that these physical bounds are realized for black holes, yielding the
correct Hawking black hole lifetime, and that space-time undergoes much larger
quantum fluctuations than conventional wisdom claims --- almost within range of
detection with modern gravitational-wave interferometers.

</DOC>
<DOC>
<DOCNO> 8215 </DOCNO>
Enhancement of the Traveling Front Speeds in Reaction-Diffusion


  We establish rigorous lower bounds on the speed of traveling fronts and on
the bulk burning rate in reaction-diffusion equation with passive advection.
The non-linearity is assumed to be of either KPP or ignition type. We consider
two main classes of flows. Percolating flows, which are characterized by the
presence of long tubes of streamlines mixing hot and cold material, lead to
strong speed-up of burning which is linear in the amplitude of the flow, $U$.
On the other hand the cellular flows, which have closed streamlines, are shown
to produce weaker increase in reaction. For such flows we get a lower bound
which grows as $U^{1/5}$ for a large amplitude of the flow.

</DOC>
<DOC>
<DOCNO> 80596 </DOCNO>
Determinant of a new fermionic action on a lattice - (I)


  We investigate, analytically and numerically, the fermion determinant of a
new action on a (1+1)-dimensional Euclidean lattice. In this formulation the
discrete chiral symmetry is preserved and the number of fermion components is a
half of that of Kogut-Susskind. In particular, we show that our fermion
determinant is real and positive for U(1) gauge group under specific
conditions, which correspond to gauge conditions on the infinite lattice. It is
also shown that the determinant is real and positive for SU(N) gauge group
without any condition.

</DOC>
<DOC>
<DOCNO> 99948 </DOCNO>
A Two Dimensional Analogue of the Virasoro Algebra


  The author regrets that after discussion of the results with B. L. Feigin a
serious error has shown up. The proof of the results we presented in the paper
is wrong. We thank B. L. Feigin for the discussion.

</DOC>
<DOC>
<DOCNO> 152105 </DOCNO>
Gravity as Lorentz Force


  The main object of the proposed theory is not a pseudometric, but a symmetric
affine connection on the Minkowski space. The coefficients of this connection
have one upper and two lower indices. These coefficients are symmetric with
respect to the permutation of the lower indices. We identify the convolution of
the connection coefficients with the vector - potential of the electromagnetic
field. Then the gravity is the Lorentz force of this electromagnetic field.

</DOC>
<DOC>
<DOCNO> 169912 </DOCNO>
Wavefunction Collapse and Conservation Laws


  It is emphasized that the collapse postulate of standard quantum theory can
violate conservation of energy-momentum and there is no indication from where
the energy-momentum comes or to where it goes. Likewise, in the Continuous
Spontaneous Localization (CSL) dynamical collapse model, particles gain energy
on average. In CSL, the usual Schr\"odinger dynamics is altered so that a
randomly fluctuating classical field interacts with quantized particles to
cause wavefunction collapse. In this paper it is shown how to define energy for
the classical field so that the average value of the energy of the field plus
the quantum system {\it is} conserved for the ensemble of collapsing
wavefunctions. While conservation of just the first moment of energy is, of
course, much less than complete conservation of energy, this does support the
idea that the field could provide the conservation law balance when events
occur.

</DOC>
<DOC>
<DOCNO> 122415 </DOCNO>
PSCz vs. 1.2 Jy velocity fields: a Spherical Harmonics Comparison


  We perform a detailed comparison of the IRAS PSCz and 1.2-Jy spherical
harmonic coefficients of the predicted velocity fields in redshift space. The
monopole terms predicted from the two surveys show some differences. Faint
galaxies are responsible for this mismatch that disappears when extracting a
PSCz subsample of galaxies with fluxes larger than 1.2 Jy. The analysis of PSCz
dipole components confirms the same inconsistencies found by Davis, Nusser and
Willick (1996) between the IRAS 1.2-Jy gravity field and MARKIII peculiar
velocities.
 Shot-noise, which is greatly reduced in our PSCz gravity field, cannot be
responsible for the observed mismatch.

</DOC>
<DOC>
<DOCNO> 83290 </DOCNO>
Systematic Testing of Multicast Routing Protocols: Analysis of Forward


  In this paper, we present a new methodology for developing systematic and
automatic test generation algorithms for multipoint protocols. These algorithms
attempt to synthesize network topologies and sequences of events that stress
the protocol's correctness or performance. This problem can be viewed as a
domain-specific search problem that suffers from the state space explosion
problem. One goal of this work is to circumvent the state space explosion
problem utilizing knowledge of network and fault modeling, and multipoint
protocols. The two approaches investigated in this study are based on forward
and backward search techniques. We use an extended finite state machine (FSM)
model of the protocol. The first algorithm uses forward search to perform
reduced reachability analysis. Using domain-specific information for multicast
routing over LANs, the algorithm complexity is reduced from exponential to
polynomial in the number of routers. This approach, however, does not fully
automate topology synthesis. The second algorithm, the fault-oriented test
generation, uses backward search for topology synthesis and uses backtracking
to generate event sequences instead of searching forward from initial states.
Using these algorithms, we have conducted studies for correctness of the
multicast routing protocol PIM. We propose to extend these algorithms to study
end-to-end multipoint protocols using a virtual LAN that represents delays of
the underlying multicast distribution tree.

</DOC>
<DOC>
<DOCNO> 13981 </DOCNO>
Reentrant behaviour and universality in the Anderson transition


  The three-dimensional Anderson model with a rectangular distribution of site
disorder displays two distinct localization-delocalization transitions, against
varying disorder intensity, for a relatively narrow range of Fermi energies.
Such transitions are studied through the calculation of localization lengths of
quasi-- one-dimensional systems by transfer-matrix methods, and their analysis
by finite-size scaling techniques. For the transition at higher disorder we
find the localization-length exponent $\nu=1.60(5)$ and the limiting scaled
localization-length amplitude $\Lambda_0=0.57(1)$, strongly suggesting
universality with the transition at the band centre, for which currently
accepted values are $\nu=1.57(2)$ and $\Lambda_0=0.576(2)$. For the lower
(reentrant) transition, we estimate $\nu=1.55(15)$ and $\Lambda_0=0.55(5)$,
still compatible with universality but much less precise, partly owing to
significant finite-size corrections.

</DOC>
<DOC>
<DOCNO> 123308 </DOCNO>
A Non-Triggered Burst Supplement to the BATSE Gamma-Ray Burst Catalogs


  The Burst and Transient Source Experiment (BATSE) on the Compton Gamma Ray
Observatory detected gamma-ray bursts (GRBs) with a real-time burst detection
(or "trigger") system running onboard the spacecraft. Under some circumstances,
however, a GRB may not have activated the onboard burst trigger. For example,
the burst may have been too faint to exceed the onboard detection threshold, or
it may have occurred while the onboard burst trigger was disabled for technical
reasons. This paper describes a catalog of 873 "non-triggered" GRBs that were
detected in a search of the archival continuous data from BATSE, recorded
between 1991 December 9.0 and 1997 December 17.0. For each burst, the catalog
gives an estimated source direction, duration, peak flux, and fluence. Similar
data are presented for 50 additional bursts of unknown origin that were
detected in the 25--50 keV range; these events may represent the low-energy
"tail" of the GRB spectral distribution. This catalog increases the number of
GRBs detected with BATSE by 48% during the time period covered by the search.

</DOC>
<DOC>
<DOCNO> 169806 </DOCNO>
Complete quantum teleportation with a Kerr nonlinearity


  We present a scheme for the quantum teleportation of the polarization state
of a photon employing a cross-Kerr medium. The experimental feasibility of the
scheme is discussed and we show that, using the recently demonstrated ultraslow
light propagation in cold atomic media, our proposal can be realized with
presently available technology.

</DOC>
<DOC>
<DOCNO> 9547 </DOCNO>
Simple Microscopic Theory of Amontons' Laws for Static Friction


  A microscopic theory for the ubiquitous phenomenon of static friction is
presented. Interactions between two surfaces are modeled by an energy penalty
that increases exponentially with the degree of surface overlap. The resulting
static friction is proportional to load, in accordance with Amontons' laws.
However the friction coefficient between bare surfaces vanishes as the area of
individual contacts grows, except in the rare case of commensurate surfaces. An
area independent friction coefficient is obtained for any surface geometry when
an adsorbed layer of mobile atoms is introduced between the surfaces. The
predictions from our simple analytic model are confirmed by atomistically
detailed molecular dynamics simulations.

</DOC>
<DOC>
<DOCNO> 99618 </DOCNO>
Soliton equations in N-dimensions as exact reductions of the Self-Dual


  Some aspects of the multidimensional soliton geometry are considered. It is
shown that some simples (2+1)-dimensional equations are exact reductions of the
Self-Dual Yang-Mills equation or its higher hierarchy.

</DOC>
<DOC>
<DOCNO> 102047 </DOCNO>
Symmetry, splitting rational places in extensions of function fields and


  The notion of symmetry in polynomial rings with several indeterminates is
generalized to polynomial rings over finite fields. Families of extensions of
the projective line over a finite field of constants possessing this property
are explicitly constructed. These extensions exhibit complete splitting of all
finite rational places. Subcovers of these extensions are also explicitly
described. New examples of function fields attaining the Oesterle bounds are
obtained. These constructions are compared with class field theoretic
constructions achieving similar splitting of rational places. A generalization
to the Hermitian function field over fields of non-square cardinality is
proposed.

</DOC>
<DOC>
<DOCNO> 118509 </DOCNO>
A model for the alternating phase lags associated with QPOs in X-ray


  We present a theoretical model for the alternating phase lags associated with
QPO fundamental and harmonic frequencies observed in some Galactic black-hole
candidates. We assume that the accretion flow exhibits a transition from an
outer cool, optically thick accretion disk to a hot, inner advection-dominated
accretion flow (ADAF), and that the QPOs are related to small-scale
oscillations of the accretion rate and the transition radius. We present an
analytical estimate of the expected phase lags at the fundamental and first
harmonic frequencies of the QPOs and perform detailed time-dependent
Monte-Carlo simualtions of the radiation transport in the oscillating ADAF /
cool disk system. We find that this model is well suited to reproduce
alternating phase lags between the fundamental and the first harmonic. It also
naturally explains the trend observed in GRS 1915+105 that, as the soft X-ray
luminosity increases, the QPO frequency increases and the phase lag associated
with the QPO fundamental frequency changes sign from positive to negative. The
relation between the disk temperature and the QPO frequency observed in GRS
1915+105 is consistent with a secular instability modulating the disk
evaporation at the transition radius.

</DOC>
<DOC>
<DOCNO> 101371 </DOCNO>
Integrability, Random Matrices and Painlev\'e Transcendents


  The probability that an interval $I$ is free of eigenvalues in a matrix
ensemble with unitary symmetry is given by a Fredholm determinant. When the
weight function in the matrix ensemble is a classical weight function, and the
interval $I$ includes an endpoint of the support, Tracy and Widom have given a
formalism which gives coupled differential equations for the required
probability and some auxilary quantities. We summarize and extend earlier work
by expressing the probability and some of the auxilary quantities in terms of
Painlev\'e transcendents.

</DOC>
<DOC>
<DOCNO> 40284 </DOCNO>
Charm Physics at Fermilab E791


  Experiment 791 at Fermilab's Tagged Photon Laboratory has just accumulated a
high statistics charm sample by recording 20 billion events on 24000 8mm tapes.
A 500 GeV/c pi- beam was used with a fixed target and a magnetic spectrometer
which now includes 23 silicon fixed target and a magnetic spectrometer which
now includes 23 silicon microstrip planes for vertex reconstruction. A new data
acquisition system read out 9000 events/sec during the part of the Tevatron
cycle that delivered beam. Digitization and readout took 50 uS per event. Data
was buffered in eight large FIFO memories to allow continuous event building
and continuous tape writing to a wall of 42 Exabytes at 9.6 MB/sec. The 50
terabytes of data buffered to tape is now being filtered on RISC CPUs.
Preliminary results show D0 --> K- pi+ and D+ --> K- pi+ pi+ decays. Rarer
decays will be pursued.

</DOC>
<DOC>
<DOCNO> 102027 </DOCNO>
The Hilbert 16-th problem and an estimate for cyclicity of an elementary


  Hilbert-Arnold (HA) problem, motivated by Hilbert 16-th problem, is to prove
that for a generic k-parameter family of smooth vector fields {\dot
x=v(x,\eps)}_{\eps\in B^k} on the 2-dimensional sphere S^2 has uniformly
bounded number of limit cycles (isolated periodic solutions), denoted by
LC(\eps), over the parameter \eps, i.e. max_{\eps \in B^k} LC(\eps) <= K <
\infty for some K.
  The HA problem can be reduced to so-called Local Hilbert-Arnold (LHA)
problem. Suppose that a generic k-parameter family {\dot x=v(x,\eps)}_{\eps \in
B^k}, x\in S^2 for some parameter \eps^*\in B^k has a polycycle (separatrix
polygon) gamma consisting of equilibrium points as vertices and connecting
separatrices as sides. LHA problem is to estimate B(k)--- the maximal number of
limit cycles that can be born in a neighbourhood of gamma for a field \dot
x=v(x,\eps), where \eps is close to \eps^*.

</DOC>
<DOC>
<DOCNO> 9826 </DOCNO>
Contact resistance between carbon nanotubes


  Quantum transport properties of intermolecular nanotube contacts are
investigated. We find that atomic structure in the contact region plays
important roles and resistance of contacts varies strongly with geometry and
nanotube chirality. Nanotube end-end contacts have low resistance and show
negative differential resistance (NDR) behavior. Contact resistance can be
dramatically decreased by exerting small pressure/force between the tubes if
the contact is commensurate. Significant variation and nonlinearity of contact
resistance may lead to new device applications.

</DOC>
<DOC>
<DOCNO> 117573 </DOCNO>
Evidence for Stellar Streaming in the Cores of Elliptical Galaxies: A


  We present evidence for non-Gaussian velocity fields within the cores of
luminous elliptical galaxies. This evidence is based upon high signal-to-noise,
medium-resolution spectroscopy of the cores of early-type members of the Virgo
and Coma clusters obtained with the WIYN 3.5-m telescope. The Virgo data were
acquired using an integral-field unit (DensePak) allowing the velocity field to
be sampled over a variety of spatial scales. The Coma data were obtained
through single, 2-arcsec diameter fibers. The cross-correlation profiles of
luminous ellipticals show considerable structure, often having several features
with amplitudes as high as 10% that of the cross-correlation peak itself. This
structure is most obvious within a radius of 1.5 arcsec (at Virgo), or < 100
pc, and is nearly undetectable when the data are binned over R < 15 arcsec, or
< 1 kpc. Similar features are found in the single-fiber spectra of the luminous
ellipticals in the Coma Cluster suggesting they are ubiquitous to giant
ellipticals. Interesting, only the most luminous elliptical galaxies show this
phenomena; the central regions of lower luminosity ellipticals have regular,
Gaussian-like profiles. We interpret this kinematic structure as ``stellar
streaming'' and suggest that this phenomena could be a relic signature of the
merger history of luminous elliptical galaxies.

</DOC>
<DOC>
<DOCNO> 119261 </DOCNO>
Galaxy Distances via Rotational Parallaxes


  Accurate distances to stars and galaxies allow for significant tests of
stellar evolution, galaxy formation and evolution and cosmology. NASA's Space
Interferometry Mission (SIM) will obtain precision [1-30 microarcsec]
astrometry for 10-20k objects brighter than V=20 mag.
   In this paper we discuss a method to determine the distance of nearby spiral
galaxies using the technique of rotational parallaxes, and show that it is
possible to achieve distance errors of only a few percent. With such distances
at hand, it becomes possible to determine an accurate zero-point for the
Tully-Fisher relation, one of the tools to measure distances throughout the
universe.
   The rotational parallax method employs the common orbital motions of a of
stars within a galaxy to determine their distance. For stars on circular
orbits, the two proper motions and the radial velocity suffice to determine the
inclination of the orbit, the rotational velocity and the distance. Several
factors complicate the application of this simple technique to real galaxies:
1) the target galaxy may have substantial space-motion, 2) stars in real
galaxies are not on circular orbits (e.g. due to spiral-arm streaming motions
or induced by random motions), 3) stars in the galaxy are at significantly
different distances from the Sun (the near side of M 31 is ~5% closer than the
far side).
   Notwithstanding these complication, distances can be determined to within
several percent for the nearest spirals. (abridged)

</DOC>
<DOC>
<DOCNO> 100377 </DOCNO>
Meromorphic Groups


  We introduce the notion of a meromorphic group, weakening somewhat Fujiki's
definition We prove that a meromorphic group is meromorphically an extension of
a complex torus by a linear algebraic group, generalizing results in [Fujiki,
1978]. A special case of this result, as well as one of the ingredients in the
proof, is that a strongly minimal "modular" meromorphic group is a complex
torus, answering a question of Hrushovski. As a consequence, we show that a
simple compact complex manifold has algebraic and Kummer dimension zero if an
only if its generic type is trivial.

</DOC>
<DOC>
<DOCNO> 101081 </DOCNO>
Fusion rules for the continuum sectors of the Virasoro algebra with c=1


  The Virasoro algebra with c=1 has a continuum of superselection sectors
characterized by the ground state energy h. Only a discrete subset of sectors
arises by restriction of representations of the SU(2) current algebra at level
k=1. The remaining continuum of sectors is obtained with the help of
(localized) homomorphisms into the current algebra. The fusion product of
continuum sectors with discrete sectors is computed. A new method of
determining the sector of a state is used.

</DOC>
<DOC>
<DOCNO> 69790 </DOCNO>
Probing Quantum Aspects of Gravity


  We emphasize that a specific aspect of quantum gravity is the absence of a
super-selection rule that prevents a linear superposition of different
gravitational charges. As an immediate consequence, we obtain a tiny, but
observable, violation of the equivalence principle, provided, inertial and
gravitational masses are not assumed to be operationally identical objects. In
this framework, the cosmic gravitational environment affects local experiments.
A range of terrestrial experiments, from neutron interferometry to neutrino
oscillations, can serve as possible probes to study the emergent quantum
aspects of gravity.

</DOC>
<DOC>
<DOCNO> 71016 </DOCNO>
SUSY Breaking by Overlap of Wave Functions in Coexisting Walls


  SUSY breaking without messenger fields is proposed. We assume that our world
is on a wall and SUSY is broken only by the coexistence of another wall with
some distance from our wall. The Nambu-Goldstone fermion is localized on the
distant wall. Its overlap with the wave functions of physical fields on our
wall gives the mass splitting of physical fields on our wall thanks to a
low-energy theorem. We propose that this overlap provides a practical method to
evaluate mass splitting in models with SUSY breaking due to the coexisting
walls.

</DOC>
<DOC>
<DOCNO> 84594 </DOCNO>
Brane surgery: energy conditions, traversable wormholes, and voids


  Branes are ubiquitous elements of any low-energy limit of string theory. We
point out that negative tension branes violate all the standard energy
conditions of the higher-dimensional spacetime they are embedded in; this opens
the door to very peculiar solutions of the higher-dimensional Einstein
equations. Building upon the (3+1)-dimensional implementation of fundamental
string theory, we illustrate the possibilities by considering a toy model
consisting of a (2+1)-dimensional brane propagating through our observable
(3+1)-dimensional universe. Developing a notion of "brane surgery", based on
the Israel--Lanczos--Sen "thin shell" formalism of general relativity, we
analyze the dynamics and find traversable wormholes, closed baby universes,
voids (holes in the spacetime manifold), and an evasion (not a violation) of
both the singularity theorems and the positive mass theorem. These features
appear generic to any D-brane model that permits negative tension branes: This
includes the Randall--Sundrum models and their variants.

</DOC>
<DOC>
<DOCNO> 152045 </DOCNO>
A Non-perturbative Estimate of Vacuum Polarization in QED


  We present a new estimate of the fine structure constant and the
$\beta$-function of QED at an arbitrary scale. Using the non-perturbative but
convergent series expression of the one loop effective action of QED that has
been available recently we make a non-perturbative estimate of the running
coupling and the $\beta$-function, and prove the renormalization group
invariance of the effective action. The contrast between our result and the
perturbative result is remarkable.

</DOC>
<DOC>
<DOCNO> 151856 </DOCNO>
BCFT: from the boundary to the bulk


  The study of boundary conditions in rational conformal field theories is not
only physically important. It also reveals a lot on the structure of the theory
``in the bulk''. The same graphs classify both the torus and the cylinder
partition functions and provide data on their hidden ``quantum symmetry''. The
Ocneanu triangular cells -- the 3j-symbols of these symmetries, admit various
interpretations and make a link between different problems.

</DOC>
<DOC>
<DOCNO> 122986 </DOCNO>
Gaseous Disks of Spiral Galaxies: Arms and Rings


  An improved linear stability theory of small-amplitude oscillations of a
self-gravitating, infinitesimally thin gaseous disk of spiral galaxies has been
developed. It was shown that in the differentially rotating disks for
nonaxisymmetric perturbations Toomre's modified hydrodynamical simulations to
test the validity of the modified local criterion.

</DOC>
<DOC>
<DOCNO> 120323 </DOCNO>
Simulated Extragalactic Observations with a Cryogenic Imaging


  In this paper we explore the application of cryogenic imaging
spectrophotometers. Prototypes of this new class of detector, such as
superconducting tunnel junctions (STJs) and transition edge sensors (TESs),
currently deliver low resolution imaging spectrophotometry with high quantum
efficiency (70-100%) and no read noise over a wide bandpass in the visible to
near-infrared. In order to demonstrate their utility and the differences in
observing strategy needed to maximize their scientific return, we present
simulated observations of a deep extragalactic field. Using a simple analytic
technique, we can estimate both the galaxy redshift and spectral type more
accurately than is possible with current broadband techniques. From our
simulated observations and a subsequent discussion of the expected migration
path for this new technology, we illustrate the power and promise of these
devices.

</DOC>
<DOC>
<DOCNO> 68219 </DOCNO>
Axial Symmetry and Bound States of Particles with Anomalous Magnetic


  We consider bound states of fermions with an anomalous magnetic moments in
the field of charged cylinder.Also we obtain second order equations for axially
symmetric $Z_0(r)$-boson field, radial axially symmetric magnetic field, obtain
second order equations for case of bound states of fermions in the radial
electric and magnetic fields.

</DOC>
<DOC>
<DOCNO> 7907 </DOCNO>
Electronic Structure of Carbon Nanotube Ropes


  We present a tight binding theory to analyze the motion of electrons between
carbon nanotubes bundled into a carbon nanotube rope. The theory is developed
starting from a description of the propagating Bloch waves on ideal tubes, and
the effects of intertube motion are treated perturbatively in this basis.
Expressions for the interwall tunneling amplitudes between states on
neighboring tubes are derived which show the dependence on chiral angles and
intratube crystal momenta. We find that conservation of crystal momentum along
the tube direction suppresses interwall coherence in a carbon nanorope
containing tubes with random chiralities. Numerical calculations are presented
which indicate that electronic states in a rope are localized in the transverse
direction with a coherence length corresponding to a tube diameter.

</DOC>
<DOC>
<DOCNO> 68060 </DOCNO>
Is it possible to determine the S-factor of the hep process from a


  We discuss the problem of solar hep neutrinos originating from the reaction p
+ 3He -> 4He + e+ + nu and obtain a relation between the astrophysical S-factor
of the hep process and the cross section of the process e- + 4He -> 3H + n + nu
near threshold. The relation is based on the isotopic invariance of strong
interactions.
 The measurement of the latter cross section would allow to obtain experimental
information on S(hep), the value of which, at the moment, is known only from
theoretical calculations.

</DOC>
<DOC>
<DOCNO> 120838 </DOCNO>
The Planetary System of Upsilon Andromedae


  The bright F8 V solar-type star upsilon Andromedae has recently been reported
to have a system of three planets of Jovian masses. In order to investigate the
orbital stability and mutual gravitational interactions among these extrasolar
planets, both forward and backward integrations from the latest observed
orbital elements for all three planets' orbits have been performed under the
coplanar assumption. We reconfirm that the middle and the outer planet have
strong interaction leading to large time variations in the eccentricities of
these planets, which was shown by the previous studies. However, we discuss the
validity of the ignorance of the innermost planet. We argue that this planetary
system is likely to be stable and oscillate around current orbital elements
since it was formed.
  We suggest that one possible way to produce these orbital elements: the
innermost planet has very low eccentricity but the outermost planet has high
eccentricity could be the interaction with the protostellar disc.

</DOC>
<DOC>
<DOCNO> 12688 </DOCNO>
Spin-Orbit Coupling in the ab initio Pseudopotential Framework


  We describe the implementation of total angular momentum dependent
pseudopotentials in a plane wave formulation of density functional theory. Our
approach thus goes beyond the scalar-relativistic approximation usually made in
ab initio pseudopotential calculations and explicitly includes spin-orbit
coupling. We outline the necessary extensions and compare the results to
available all-electron calculations and experimental data.

</DOC>
<DOC>
<DOCNO> 118424 </DOCNO>
The High-Ionization Nuclear Emission-Line Region of Seyfert Galaxies


  Recently Murayama & Taniguchi proposed that a significant part of the
high-ionization nuclear emission-line region (HINER) in Seyfert nuclei arises
from the inner wall of dusty tori because type 1 Seyfert nuclei (S1s) show the
excess HINER emission with respect to type 2 Seyfert ones (S2s). This means
that the radiation from the HINER has the anisotropic property and thus
statistical properties of the HINER emission can be used to investigate the
viewing angle toward dusty tori for various types of Seyfert nuclei. In order
to investigate viewing angles toward various types of Seyferys, we apply this
HINER test to them.
  Our main results are as follows. (1) The NLS1s are viewed from a more face-on
view toward dusty tori than the S2s. However, the HINER properties of the NLS1s
are indistinguishable from those of the S1s. (2) The type 1.5 Seyferts appear
to comprise heterogeneous populations. (3) The type 1.8 and 1.9 Seyferts and
the objects showing either a broad Pa_beta line or polarized broad Balmer lines
are seen from a large inclination angle and the emission from the BLRs of such
objects reaches us through optically-thin parts of dusty tori. These three
results support strongly the current unified model of Seyfert nuclei. And, (4)
the line ratios of [Fe X]6374 to the low-ionization emission-lines have rather
isotropic property than those of [Fe VII]6087. Therefore it is suggested that
the [Fe X] emission is not useful investigating the viewing angle toward the
dusty torus in Seyfert nuclei. The most plausible reason seems that the [Fe X]
emission is spatially extended and thus its strength tends to show less viewing
angle dependence.

</DOC>
<DOC>
<DOCNO> 121750 </DOCNO>
The Optical Gravitational Lensing Experiment. Stellar Distance


  BVI photometry of the Magellanic Clouds collected during the OGLE-II
microlensing experiment makes it possible to study in detail photometric
properties of the "major" stellar distance indicators in the Magellanic Clouds.
In addition to Cepheids, RR Lyr and red clump stars, which photometry was
presented in the earlier OGLE papers, we present the so far most accurate
determination of brightness of the tip of the red giant branch in the LMC and
SMC. We analyze the ratios of brightness of all four distance indicators in the
LMC and SMC. Additionally, we include in our analysis, when possible,
photometric data of the distance indicators in the metal poor Carina dwarf
galaxy for which photometry was also collected during the OGLE-II experiment.
The analysis is largely differential, free from zero point and extinction
uncertainties. The main conclusion is that the distance scales resulting from
all four stellar distance indicators are fully consistent with each other.
Therefore the distance scale problem is not a problem resulting from different
distances yielded by distance indicators, but rather a problem of the proper
zero point of this common distance scale. All four stellar distance indicators
have to be treated as an ensemble, and any determination of the zero point for
one of them must predict reasonable luminosities of the others. This puts
strong constraints on many proposed calibrations of distance indicators. For
example, very bright calibrations of Cepheids or RR Lyr can practically be
ruled out. (Abridged).

</DOC>
<DOC>
<DOCNO> 121318 </DOCNO>
The Accelerations of Stars Orbiting the Milky Way's Central Black Hole


  Recent measurements, of the velocities of stars near the center of the Milky
Way have provided the strongest evidence for the presence of a supermassive
black hole in a galaxy, but the observational uncertainties poorly constrain
many of the properties of the black hole. Determining the accelerations of
stars in their orbits around the center provides much more precise information
about the position and mass of the black hole. Here we report measurements of
the accelerations for three stars located ~0.005 pc from the central radio
source Sgr A*; these accelerations are comparable to those experienced by the
Earth as it orbits the Sun. These data increase the inferred minimum mass
density in the central region of the Galaxy by an order of magnitude relative
to previous results and localized the dark mass to within 0.05 +- 0.04 arcsec
of the nominal position of Sgr A*. In addition, the orbital period of one of
the observed stars could be as short as 15 years, allowing us the opportunity
in the near future to observe an entire period.

</DOC>
<DOC>
<DOCNO> 11192 </DOCNO>
Memory and superposition in a spin glass


  Non-equilibrium dynamics in a Ag(Mn) spin glass are investigated by
measurements of the temperature dependence of the remanent magnetisation. Using
specific cooling protocols before recording the thermo- or isothermal remanent
magnetisations on re-heating, it is found that the measured curves effectively
disclose non-equilibrium spin glass characteristics such as ageing and memory
phenomena as well as an extended validity of the superposition principle for
the relaxation. The usefulness of this "simple" dc-method is discussed, as well
as its applicability to other disordered magnetic systems.

</DOC>
<DOC>
<DOCNO> 71318 </DOCNO>
Fragmentation Functions for Pions, Kaons, and Protons at Next-to-Leading


  We present new sets of fragmentation functions for charged pions, charged
kaons, and protons, both at the leading and next-to-leading orders. They are
fitted to the scaled-momentum distributions of these hadrons measured in e+e-
annihilation on the Z-boson resonance at CERN LEP1 and SLAC SLC. These data
partly come as light-, charm-, bottom-quark-enriched and gluon-jet samples,
which allows us to treat all partons independently, after imposing the SU(2)
flavour symmetry relations. In order to gain sensitivity to the scaling
violation in fragmentation, we also include data from SLAC PEP, with
center-of-mass energy root(s)=29 GeV, in our fits. This allows us to also
determine the strong-coupling constant, with a competitive error. LEP1 data on
the longitudinal cross section as well as DESY DORIS and PETRA data at lower
energies nicely agree with theoretical predictions based on our fragmentation
functions.

</DOC>
<DOC>
<DOCNO> 80741 </DOCNO>
Renormalization and O(a)-improvement of the static-light axial current


  A systematic treatment of O(a)-improvement in lattice theories with static
quarks is presented. The Schr\"odinger functional is discussed and a
renormalization condition for the static axial current in the SF-scheme is
introduced. Its relation to other schemes is computed to 1-loop order and the
2-loop anomalous dimension is derived. In finite volume renormalization schemes
such as the SF-scheme, the renormalization scale dependence of the renormalized
quantities is described by the step scaling function which can be computed by
MC- simulations. We evaluate its lattice spacing effects in perturbation
theory.

</DOC>
<DOC>
<DOCNO> 13392 </DOCNO>
The Schrodinger Cat Family in Attractive Bose Gases and Their


  We show that the ground state of an attractive Bose gas in a double well
evolves from a coherent state to a Schrodinger Cat like state as the tunneling
barrier is decreased. The latter exhibits super- fragmentation as spin-1 Bose
gas with antiferromagnetic interaction, which is caused by the same physics. We
also show that the fragmented condensates of attractive and repulsive Bose
gases in double wells lead to very different interference patterns.

</DOC>
<DOC>
<DOCNO> 119640 </DOCNO>
The Nature of the Lithium Rich Giants. Mixing episodes on the RGB and


  We present a critical analysis of the nature of the so-called Li-rich RGB
stars. For a majority of the stars, we have used Hipparcos parallaxes to
determine masses and evolutionary states by comparing their position on the
Hertzsprung-Russell diagram with theoretical evolutionary tracks. Among the
twenty Li-rich giants whose location on the HR diagram we were able to
determine precisely, eight should be re-classified as Li-normal. For the
remaining stars, the high Li abundance must be a result of fresh synthesis of
this fragile element. We identify two distinct episodes of Li production which
occur in advanced evolutionary phases depending upon the mass of the star. We
suggest that the Li-rich stars are formed mainly as a precursor to the deeper
mixing process which produces anomalously low carbon isotopic ratios. Low-mass
RGB stars, which later undergo the helium flash, produce Li at the phase
referred to as the bump in the luminosity function. In intermediate-mass stars,
the Li-rich phase occurs on the early-AGB. The compiled data provide
constraints on the time scales for extra mixing and some insight on processes
suggested in the literature. However, our results do not suggest any specific
trigger mechanism. Since the Li-rich phases are extremely short, enrichment of
the Li content of the ISM as a result of these episodes is negligible.

</DOC>
<DOC>
<DOCNO> 119712 </DOCNO>
Multiphase Smoothed-Particle Hydrodynamics


  We adapt the Smoothed-Particle Hydrodynamics technique to allow a multiphase
fluid in which SPH particles of widely differing density may be freely
intermixed. Applications include modelling of galaxy formation and cooling
flows.

</DOC>
<DOC>
<DOCNO> 69718 </DOCNO>
Electroweak radiative corrections to e+e- --> WW --> 4fermions in


  We calculate the complete O(alpha) electroweak radiative corrections to e+e-
--> WW --> 4f in the electroweak Standard Model in the double-pole
approximation. We give analytical results for the non-factorizable virtual
corrections and express the factorizable virtual corrections in terms of the
known corrections to on-shell W-pair production and W decay. The calculation of
the bremsstrahlung corrections, i.e. the processes e+e- --> 4f+gamma in lowest
order, is based on the full matrix elements. The matching of soft and collinear
singularities between virtual and real corrections is done alternatively in two
different ways, namely by using a subtraction method and by applying
phase-space slicing. The O(alpha) corrections as well as higher-order
initial-state photon radiation are implemented in the Monte Carlo generator
RACOONWW. Numerical results of this program are presented for the
W-pair-production cross section, angular and W-invariant-mass distributions at
LEP2. We also discuss the intrinsic theoretical uncertainty of our approach.

</DOC>
<DOC>
<DOCNO> 117491 </DOCNO>
Synthesis of 19F in Wolf-Rayet stars


  Meynet and Arnould (1993) have suggested that Wolf-Rayet (WR) stars could
significantly contaminate the Galaxy with 19F. In their scenario, 19F is
synthesized at the beginning of the He-burning phase from the 14N left over by
the previous CNO-burning core, and is ejected in the interstellar medium when
the star enters its WC phase. Recourse to CNO seeds makes the 19F yields
metallicity-dependent. These yields are calculated on grounds of detailed
stellar evolutionary sequences for an extended range of initial masses (from 25
to 120 Msol) and metallicities (Z = 0.008, 0.02 and 0.04). The adopted mass
loss rate prescription enables to account for the observed variations of WR
populations in different environments. The 19F abundance in the WR winds of 60
Msol model stars is found to be about 10 to 70 times higher than its initial
value, depending on the metallicity. This prediction is used in conjunction
with a very simple model for the chemical evolution of the Galaxy to predict
that WR stars could be significant (dominant?) contributors to the solar system
fluorine content. We also briefly discuss the implications of our model on the
possible detection of fluorine at high redshift.

</DOC>
<DOC>
<DOCNO> 12434 </DOCNO>
On the Fluctuation Law(s) for Hamiltonian systems (with equilibrium


  A generalization of the fluctuation law (FL) ("theorem"), formulated in 1993
by Evans, Cohen and Morriss for a nonequilibrium steady state, on the chaotic
Hamiltonian systems with equilibrium steady state in recent publication ba
Evans, Searles and Mittag (cond-mat/0008421) is briefly discussed. We argue
that the physical meaning of this law, as presented in the latter publication,
is qualitatively different from the original one. Namely, the original FL
concerns the local (in time) fluctuations with an intriguing result: a high
probability for the "violation" of the Second Law. Instead, the new law
describes the global fluctuations for which this remarkable unexpected
phenomenon is absent or hidden. We compare both types in both classes of
Hamiltonian systems, and discuss remarkable similarities as well as the
interesting distinctions.

</DOC>
<DOC>
<DOCNO> 85200 </DOCNO>
The Consistency of Causal Quantum Geometrodynamics and Quantum Field


  We consider quantum geometrodynamics and parametrized quantum field theories
in the framework of the Bohm-de Broglie interpretation. In the first case, and
following the lines of our previous work [1], where a hamiltonian formalism for
the bohmian trajectories was constructed, we show the consistency of the theory
for any quantum potential, completing the scenarios for canonical quantum
cosmology presented there. In the latter case, we prove the consistency of
scalar field theory in Minkowski spacetime for any quantum potential, and we
show, using this alternative hamiltonian method, a concrete example where
Lorentz invariance of individual events is broken.

</DOC>
<DOC>
<DOCNO> 85238 </DOCNO>
Numerical Calculation of Conformally Smooth Hyperboloidal Data


  This is the third paper in a series describing a numerical implementation of
the conformal Einstein equation. This paper describes a scheme to calculate
(three) dimensional data for the conformal field equations from a set of free
functions. The actual implementation depends on the topology of the spacetime.
We discuss the implementation and exemplary calculations for data leading to
spacetimes with one spherical null infinity (asymptotically Minkowski) and for
data leading to spacetimes with two toroidal null infinities (asymptotically
A3). We also outline the (technical) modifications of the implementation needed
to calculate data for spacetimes with two and more spherical null infinities
(asymptotically Schwarzschild and asymptotically multiple black holes).

</DOC>
<DOC>
<DOCNO> 8963 </DOCNO>
Lattice dynamics and electron-phonon coupling in \beta-(BEDT-TTF)_2I_3


  The crystal structure and lattice phonons of (BEDT-TTF)_2I_3 superconducting
\beta-phase are computed and analyzed by the Quasi Harmonic Lattice Dynamics
(QHLD) method. Whereas the crystal structure and its temperature and pressure
dependence are properly reproduced within a rigid molecule approximation, this
has to be removed to account for the specific heat data. Such a mixing between
lattice and low-frequency intramolecular vibrations also yields good agreement
with the observed Raman and infrared frequencies. From the eigenvectors of the
low-frequency phonons we calculate the electron-phonon coupling constants due
to the modulation of charge transfer (hopping) integrals. The hopping integrals
are evaluated by the extended Hueckel method applied to all nearest-neighbor
BEDT-TTF pairs in the ab crystal plane. From the averaged electron-phonon
coupling constants and the QHLD phonon density of states we derive the
Eliashberg coupling function, which compares well with that experimentally
obtained from point-contact spectroscopy. The corresponding dimensionless
coupling constant \lambda is found to be around 0.4 .

</DOC>
<DOC>
<DOCNO> 40411 </DOCNO>
Study of Z Boson Pair Production in e^+e^- Interactions at \sqrt{s}=192


  The cross section for the production of Z boson pairs is measured using the
data collected by the L3 detector at LEP in 1999 in e^+e^- collisions at
centre-of-mass energies ranging from 192 GeV up to 202 GeV. Events in all the
visible final states are selected, measuring the cross section of this process.
The special case of final states containing b quarks is also investigated. All
results are in agreement with the Standard Model predictions.

</DOC>
<DOC>
<DOCNO> 99970 </DOCNO>
Non-vanishing of the Central Derivative of Canonical Hecke L-functions


  In the early 1980s, Rohrlich began a study of canonical Hecke characters,
which are closely related to the simplest examples of CM elliptic curves. He
and Montgomery showed the non-vanishing of the central value when the
L-function has an even functional equation, and we now show the non-vanishing
of the central derivative when the functional equation is odd. Using the
results of Gross-Zagier and Kolyvagin-Logachev, we can apply the non-vanishing
to the ranks and Shafarevitch-Tate groups of the Q-curves "A(p)" studied by
Gross in his thesis. In particular, their rank is determined by a congruence
condition. http://www.math.yale.edu/users/steve/milleryang

</DOC>
<DOC>
<DOCNO> 119031 </DOCNO>
Correlations between various hardness ratios of gamma-ray bursts


  We study correlations between various hardness ratios of gamma-ray bursts
(GRBs) and investigate if there are any differences between the two classes of
the objects in the distributions of the ratios. The results suggest that,
statistically, the slope of the higher part of the spectrum of the long
duration bursts has nothing to do with that of the lower part; emissions at
higher energy bands from the bursts of both short and long duration classes
must be significantly different for different sources, while radiations at
lower energy bands of the objects are relatively similar; the spectrum of the
short duration bursts must be harder than that of the long duration bursts,
confirming what the well-known hardness-duration correlation reveals; the
profiles of the spectra between the long duration bursts must be more similar
than that between the short duration bursts. The long duration bursts would
share more common properties than the short duration bursts. A possible
interpretation is proposed with the concept of the Doppler boosting in the
relativistic beaming model in AGNs.

</DOC>
<DOC>
<DOCNO> 152261 </DOCNO>
Stretched strings and worldsheets with a handle


  In the presence of the constant background NS two-form gauge field, we
construct the worldsheet partition functions, bulk propagators and boundary
propagators for the worldsheets with a handle and a boundary. We analyze the
noncommutative $\phi^3$ field theory amplitudes that correspond to the general
two-point insertions on the two-loop nonplanar vacuum bubble. By the direct
string theory amplitude computations on the worldsheets with a handle, which
reduce to the aforementioned field theory amplitudes in the decoupling limit,
we find that the stretched string interpretation remains valid for the types of
amplitudes in consideration. This completes the demonstration that the
stretched string picture holds up in the general multiloop context.

</DOC>
<DOC>
<DOCNO> 68187 </DOCNO>
Inflation and Monopoles in Supersymmetric SU(4)_c x SU(2)_L x SU(2)_R


  We show how hybrid inflation can be successfully realized in a supersymmetric
model with gauge group G_{PS}= SU(4)_c x SU(2)_L x SU(2)_R. By including a
non-renormalizable superpotential term, we generate an inflationary valley
along which G_{PS} is broken to the standard model gauge group. Thus,
catastrophic production of the doubly charged magnetic monopoles, which are
predicted by the model, cannot occur at the end of inflation. The results of
the cosmic background explorer can be reproduced with natural values (of order
10^{-3}) of the relevant coupling constant, and symmetry breaking scale of
G_{PS} close to 10^{16} GeV. The spectral index of density perturbations lies
between unity and 0.9. Moreover, the mu-term is generated via a Peccei-Quinn
symmetry and proton is practically stable. Baryogenesis in the universe takes
place via leptogenesis. The low deuterium abundance constraint on the baryon
asymmetry, the gravitino limit on the reheat temperature and the requirement of
almost maximal mu neutrino - tau neutrino mixing from SuperKamiokande can be
simultaneously met with mu-neutrino, tau-neutrino and heaviest Dirac neutrino
masses determined from the large angle MSW resolution of the solar neutrino
problem, the SuperKamiokande results and SU(4)_c symmetry respectively.

</DOC>
<DOC>
<DOCNO> 119790 </DOCNO>
Gone with the wind: the origin of S0 galaxies in clusters


  We present the first 3-dimensional high resolution hydro-dynamical
simulations of the interaction between the hot ionised intra-cluster medium and
the cold interstellar medium of spiral galaxies. Ram pressure and
turbulent/viscous stripping removes 100% of the atomic hydrogen content of
luminous galaxies like the Milky Way within 100 million years. These mechanisms
naturally account for the morphology of S0 galaxies, the rapid truncation of
star formation implied by spectroscopic observations, as well as a host of
observational data on the HI morphology of galaxies in clusters.

</DOC>
<DOC>
<DOCNO> 170377 </DOCNO>
Quantum codes from cyclic codes over GF(4^m)


  We provide a construction for quantum codes (hermitian-self-orthogonal codes
over GF(4)) starting from cyclic codes over GF(4^m). We also provide examples
of these codes some of which meet the known bounds for quantum codes.

</DOC>
<DOC>
<DOCNO> 118536 </DOCNO>
Influence of new reaction rates on 18F production in novae


  Gamma-ray emission from classical novae is dominated, during the first hours,
by positron annihilation resulting from the beta decay of radioactive nuclei.
The main contribution comes from the decay of 18F and hence is directly related
to 18F formation during the outburst. A good knowledge of the nuclear reaction
rates of production and destruction of 18F is required to study 18F synthesis
in novae and the resulting gamma-ray emission. The rates relevant for the main
mode of 18F destruction (i.e, through proton captures) have been the object of
many recent experiments. However, subsequent analyses were focused on providing
rates for X-ray burst nucleosynthesis not valid at nova temperatures (lower
than 3.5 10^8 K). Accordingly, it is crucial to propose and discuss new
reaction rates, incorporating all new experimental results, down to the domain
of nova nucleosynthesis. We show that in this temperature regime, the
18F(p,gamma) and (p,alpha) reaction rates remain uncertain and deserve further
experimental and theoretical efforts. Our hydrodynamic calculations including
the new nuclear rates demonstrate that their impact on 18F synthesis in nova
explosions is quite large and, consequently, the early gamma-ray emission from
classical novae is also affected.

</DOC>
<DOC>
<DOCNO> 12934 </DOCNO>
Noise of a Quantum-Dot System in the Cotunneling Regime


  We study the noise of the cotunneling current through one or several
tunnel-coupled quantum dots in the Coulomb blockade regime. The various regimes
of weak and strong, elastic and inelastic cotunneling are analyzed for
quantum-dot systems (QDS) with few-level, nearly-degenerate, and continuous
electronic spectra. We find that in contrast to sequential tunneling where the
noise is either Poissonian (due to uncorrelated tunneling events) or
sub-Poissonian (suppressed by charge conservation on the QDS), the noise in
inelastic cotunneling can be super-Poissonian due to switching between QDS
states carrying currents of different strengths. In the case of weak
cotunneling we prove a non-equilibrium fluctuation-dissipation theorem which
leads to a universal expression for the noise-to-current ratio (Fano factor).
In order to investigate strong cotunneling we develop a microscopic theory of
cotunneling based on the density-operator formalism and using the projection
operator technique. The master equation for the QDS and the expressions for
current and noise in cotunneling in terms of the stationary state of the QDS
are derived and applied to QDS with a nearly degenerate and continuous
spectrum.

</DOC>
<DOC>
<DOCNO> 67732 </DOCNO>
Reheating and Supersymmetric Flat-Direction Baryogenesis


  We re-examine Affleck-Dine baryo/leptogenesis from the oscillation of
condensates along flat directions of the supersymmetric standard model, which
attained large vevs at the end of inflationary epoque. The key observation is
that superpotential interactions couple the flat directions to other fields,
which acquire masses induced by the flat-direction vev that may be sufficiently
small for them to be kinematically accessible to inflaton decay. The resulting
plasma of inflaton decay products then may act on the flat directions via these
superpotential Yukawa couplings, inducing thermal masses and
supersymmetry-breaking A terms. In such cases the flat directions start their
oscillations at an earlier time than usually estimated. The oscillations are
also terminated earlier, due to evaporation of the flat direction condensate
produced by its interaction with the plasma of inflaton decay products. In
these cases we find that estimates for the resulting baryon/lepton asymmetry of
the universe are substantially altered. We identify scenarios for the Yukawa
couplings to the flat directions, and the order and mass scale of
higher-dimensional superpotential interactions that set the initial flat
direction vev, that might lead to acceptable baryo/leptogenesis.

</DOC>
<DOC>
<DOCNO> 9892 </DOCNO>
Crossover from percolation to diffusion


  A problem of the crossover from percolation to diffusion transport is
considered. A general scaling theory is proposed. It introduces
phenomenologically four critical exponents which are connected by two
equations. One exponent is completely new. It describes the increase of the
diffusion below percolation threshold. As an example, an exact solution of one
dimensional lattice problem is given. In this case the new exponent $q=2$.

</DOC>
<DOC>
<DOCNO> 99346 </DOCNO>
Holomorphic Functions of Exponential Growth on Abelian Coverings of a


  Let M be a projective manifold, p:M_{G} --> M a regular covering over M with
a free abelian transformation group G. We describe holomorphic functions on
M_{G} of an exponential growth with respect to the distance defined by a metric
pulled back from M. As a corollary we obtain for such functions Cartwright and
Liouville type theorems. Our approach brings together L_{2} cohomology
technique for holomorphic vector bundles on complete K\"{a}hler manifolds and
geometric properties of projective manifolds.

</DOC>
<DOC>
<DOCNO> 152214 </DOCNO>
Morita Equivalence and Interpolation of The Dirac-Born-infeld Theory on


  In the noncommutative Dirac-Born-Infeld action with Chern-Simons term, an
interpolation field $\Phi$ is used in both DBI action and Chern-Simons term.
The Morita equivalence is discussed in both the lagrangian and the Hamiltonian
formalisms, which is more transparent in this treatment.

</DOC>
<DOC>
<DOCNO> 70927 </DOCNO>
Electromagnetic corrections for the analysis of low energy pi-p


  We calculate the electromagnetic corrections to the isospin invariant mixing
angle and to the two eigenphases for the s and p-waves for low energy pi-p
elastic and charge exchange scattering. These corrections have to be applied to
the nuclear quantities obtained from phase shift analyses of the experimental
data in order to obtain the hadronic phases. We compare our results with
earlier calculations and estimate the uncertainties in the corrections.

</DOC>
<DOC>
<DOCNO> 68774 </DOCNO>
On the Behavior of F2 and its Logarithmic Slopes


  It is shown that the CKMT model for the nucleon structure function F2, taken
as the initial condition for the NLO evolution equations in perturbative QCD,
provides a good description of the HERA data when presented in the form of the
logarithmic slopes of F2 vs x and Q2 (Caldwell-plot), in the whole available
kinematic ranges. Also the results obtained for the behavior of the gluon
component of a nucleon are presented.

</DOC>
<DOC>
<DOCNO> 118367 </DOCNO>
The Power Spectrum of Rich Clusters on Near Gigaparsec Scales


  Recently, there have been numerous analyses of the redshift space power
spectrum of rich clusters of galaxies. Some of these analyses indicate a "bump"
in the Abell/ACO cluster power spectrum around k= 0.05hMpc^-1. Such a feature
in the power spectrum excludes most standard formation models and indicates
possible periodicity in the distribution of large-scale structure. However, the
data used in detecting this peak include clusters with estimated redshifts
and/or clusters outside of Abell's (1958) statistical sample, i.e. R=0
clusters. Here, we present estimations of the redshift-space power spectrum for
a newly expanded sample of 637 R >= 1 Abell/ACO clusters which has a constant
number density to z = 0.10 in the Southern Hemisphere and a nearly constant
number density to z = 0.14 in the Northern Hemisphere. The volume sampled,
\~10^8h^{-3}Mpc^{3}, is large enough to accurately calculate the power per mode
to scales approaching 10^3h^{-1}Mpc. We find the shape of the power spectrum is
is a power-law on scales 0.02 <= k <= 0.10hMpc^{-1}, with enhanced power over
less rare clusters, such as APM clusters. The slope of this power-law is n=
-1.4. The power spectrum is essentially featureless, although we do see a dip
near $k = 0.04h$Mpc$^{-1}$ which cannot be considered statistically significant
based on this data alone. We do not detect a narrow peak at $k \sim
0.05h$Mpc$^{-1}$ and there is no evidence for a turn-over in the power spectrum
as has been previously reported. We compare the shape of the Abell/ACO rich
cluster power spectrum to various linear models.

</DOC>
<DOC>
<DOCNO> 13214 </DOCNO>
Bent surface free energy differences from simulation


  We present a calculation of the change of free energy of a solid surface upon
bending of the solid. It is based on extracting the surface stress through a
molecular dynamics simulation of a bent slab by using a generalized stress
theorem formula, and subsequent integration of the stress with respect to
strain as a function of bending curvature. The method is exemplified by
obtaining and comparing free energy changes with curvature of various
reconstructed Au(001) surfaces.

</DOC>
<DOC>
<DOCNO> 178762 </DOCNO>
Examination of On-Energy Shell Approximation in Two-Step (p,n) Reaction


  We examine the on-energy shell approximation applied in our previous
estimation of the two-step contribution to (p,p') and (p,n) reactions. We
restore the effect of absorption for the intermediate propagator in order to
avoid the singularity in the transferred momentum space and calculate the
numerical integration beyond the on-energy shell. We make the depth of the
imaginary potential for the propagator as small as possible and guess the real
two-step cross sections at zero imaginary potential.
  The numerical results are already larger than those with the on-energy shell
approximation at sufficiently deep imaginary potential, and they increased as
the depth of the imaginary potential decreased. One obtains further
contribution by including the principal part of the propagator. With this
result we make a progress in solving the underestimation problem of the
spin-transverse cross section.

</DOC>
<DOC>
<DOCNO> 101216 </DOCNO>
PU(2) monopoles and links of top-level Seiberg-Witten moduli spaces


  This is the first of two articles in which we give a proof - for a broad
class of four-manifolds - of Witten's conjecture that the Donaldson and
Seiberg-Witten series coincide, at least through terms of degree less than or
equal to c-2, where c is a linear combination of the Euler characteristic and
signature of the four-manifold. This article is a revision of sections 1-3 of
an earlier version of the article dg-ga/9712005, now split into two parts,
while a revision of sections 4-7 of that earlier version appears in a recently
updated dg-ga/9712005. In the present article, we construct virtual normal
bundles for the Seiberg-Witten strata of the moduli space of PU(2) monopoles
and compute their Chern classes.

</DOC>
<DOC>
<DOCNO> 39752 </DOCNO>
Measurement of Hadron and Lepton-Pair Production at 130GeV < \sqrt{s} <


  We report on measurements of e+e- annihilation into hadrons and lepton pairs.
The data have been collected with the L3 detector at LEP at centre-of-mass
energies between 130 and 189 GeV. Using a total integrated luminosity of 243.7
pb^-1, 25864 hadronic and 8573 lepton-pair events are selected for the
measurement of cross sections and leptonic forward-backward asymmetries. The
results are in good agreement with Standard Model predictions.

</DOC>
<DOC>
<DOCNO> 69707 </DOCNO>
Large N Limit of Higher Derivative Extended CP(N) Model


  We construct a fourth-order derivative CP(N) model in 1+1 dimensions by
incorporating the topological charge density squared term into the Lagrangian.
We quantize the theory by reformulating with auxiliary fields and then
performing the path integral explicitly. We discuss the renormalizability in
the large N limit and relevance of the effective action with axion physics.

</DOC>
<DOC>
<DOCNO> 122757 </DOCNO>
The Luminosity Function of QSO Host Galaxies


  Results from an HST imaging study of 71 QSO host galaxies are presented. The
objects are selected to have redshifts less than 0.46 and total (nuclear and
host) absolute visual magnitudes brighter than -23 (H_0=50 km/s/Mpc, q_0=0.5).
We have investigated the composition of the sample with respect to host
morphology and radio loudness, and have derived the QSO host galaxy luminosity
function. The hosts are almost equally divided between radio-loud QSOs in
ellipticals, radio-quiet QSOs in ellipticals, and radio-quiet QSOs in spirals.
Radio-loud QSOs in spirals are extremely rare. Only two hosts went undetected.
There are significant differences between some of the subclasses. Elliptical
hosts are typically twice as luminous as spiral hosts, and the hosts of
radio-loud QSOs are typically 2.5 times as luminous as those of radio-quiet
QSOs. Subject to systematic uncertainties in normalization procedures, the
luminosity function of low-redshift QSO hosts closely corresponds to the bright
tail of the local normal galaxy luminosity function. The probability of a
galaxy hosting a QSO appears to increase by a factor of approximately one
million (approaching unity) as the galaxy's luminosity increases from about
0.7L* to about 7L*. (Abridged)

</DOC>
<DOC>
<DOCNO> 117566 </DOCNO>
A problem of hypothetical emerging of cosmic background radiation


  The present temperature of cosmic background radiation and the present number
density of photons of cosmic background radiation in the observed expansive and
isotropic relativistic Universe is in the standard model of universe explained
by the assumption of emergence of the photons of cosmic background radiation on
the horizon (of the most remote visibility). However, the physical analysis
shows unambiguously that this assumption contradicts the special theory of
relativity and the quantum mechanics.

</DOC>
<DOC>
<DOCNO> 70493 </DOCNO>
Lattice QCD and the CKM matrix


  These lectures (given at TASI 2000) provide an introduction to lattice
methods for nonperturbative studies of Quantum Chromodynamics. Lecture 1 (Ch.
2) is a very vanilla introduction to lattice QCD. Lecture 2 (Ch. 3) describes
examples of recent lattice calculations relevant to fixing the parameters of
the CKM matrix.

</DOC>
<DOC>
<DOCNO> 13634 </DOCNO>
Structural Critical Scattering and Magnetic Susceptibility Study of


  We report a comprehensive synchrotron x-ray scattering and magnetic
susceptibility study of diluted spin-Peierls (SP) material
Cu$_{1-x}$Zn$_x$GeO$_ 3$. Consistent with previously reported results on
Mg-doped samples, We find similar phase behaviors in the Zn-doped case: the
temperature at which the SP dimerization attains long-range order is
significantly lower than the temperature at which the spin gap is established
for doped samples, slow dynamics and Lorentzian squared intrinsic scattering
lineshape are also found for the dimerization superlattice peaks in Zn-doped
samples. In constructing the temperature versus concentration phase diagram, we
find a critical concentration x$_c\sim$2.35% for Zn-doped samples, above which
only short-range ordered SP states are found for the whole temperature range we
studied. In the complementary magnetic susceptibility study over the the same
samples, we observe the disappearance of the characteristic SP anomaly which
indicates the absence of SP transition around the x$_c$ determined by x-ray
scattering, moreover, the low-temperature N\'eel transition cusp broadening is
also confirmed in samples just above the x$_c$. By combining the information we
collected from both synchr otron x-ray and magnetic susceptibility
measurements, we clearly resolved the di screpancies reported in previous
experiments by these two techniques. In interpreting the rich phase behavior
exhibited by doped CuGeO3, we use a heur istic phenomenological model which
contains the impurity-induced competing inter actions and the phase separation
tendency upon the appearance of the N\'eel state.

</DOC>
<DOC>
<DOCNO> 100439 </DOCNO>
Geometric chaoticity leads to ordered spectra for randomly interacting


  A rotationally invariant random interaction ensemble was realized in a
single-j fermion model. The dominance of ground states with zero and maximum
spin was confirmed and explained with a statistical approach based on the
random coupling of individual angular momenta. The interpretation is supported
by the structure of the ground state wave functions.

</DOC>
<DOC>
<DOCNO> 99761 </DOCNO>
Dynamical systems admitting the normal shift


  Development of theory of dynamical systems admitting the normal shift in
1993-1999 is reviewed. Basics are given with complete proofs.

</DOC>
<DOC>
<DOCNO> 119180 </DOCNO>
Excess sub-millimetre emission from GRS 1915+105


  We present the first detections of the black hole X-ray binary GRS 1915+105
at sub-millimetre wavelengths. We clearly detect the source at 350 GHz on two
epochs, with significant variability over the 24 hr between epochs.
Quasi-simultaneous radio monitoring indicates an approximately flat spectrum
from 2 - 350 GHz, although there is marginal evidence for a minimum in the
spectrum between 15 - 350 GHz. The flat spectrum and correlated variability
imply that the sub-mm emission arises from the same synchrotron source as the
radio emission. This source is likely to be a quasi-steady partially
self-absorbed jet, in which case these sub-mm observations probe significantly
closer to the base of the jet than do radio observations and may be used in
future as a valuable diagnostic of the disc:jet connection in this source.

</DOC>
<DOC>
<DOCNO> 12914 </DOCNO>
Dynamics of mesoscopic precipitate lattices in phase separating alloys


  We investigate, via three-dimensional atomistic computer simulations, phase
separation in an alloy under external load. A regular two-dimensional array of
cylindrical precipitates, forming a mesoscopic precipitate lattice, evolves in
the case of applied tensile stress by the movement of mesoscopic lattice
defects. A striking similarity to ordinary crystals is found in the movement of
"meso-dislocations", but new mechanisms are also observed. Point defects such
as "meso-vacancies" or "meso-interstitials" are created or annihilated locally
by merging and splitting of precipitates. When the system is subjected to
compressive stress, we observe stacking faults in the mesoscopic
one-dimensional array of plate-like precipitates.

</DOC>
<DOC>
<DOCNO> 85514 </DOCNO>
Symmetries, Quantum Geometry, and the Fundamental Interactions


  A generalized Noether's theorem and the operational determination of a
physical geometry in quantum physics are used to motivate a quantum geometry
consisting of relations between quantum states that are defined by a universal
group. Making these relations dynamical implies the non local effect of the
fundamental interactions on the wave function, as in the Aharonov-Bohm effect
and its generalizations to non Abelian gauge fields and gravity. The usual
space-time geometry is obtained as the classical limit of this quantum geometry
using the quantum state space metric.

</DOC>
<DOC>
<DOCNO> 11577 </DOCNO>
Point-Contact Spectroscopy of Superconductors


  The point-contact spectroscopy, in contrast to the tunneling spectrocopy,
considers small electrical contacts with direct conductivity. In the normal
state, it enables one to measure the spectral function of electron-boson
interaction. In the superconducting state, new features appear connected with
the energy dependence of excess current. The non-linearities of the
current-voltage characteristic are due to: i) The inelastic scattering of
electron quasiparticles in the contact region; ii) The energy dependence of the
superconducting energy gap, and iii) The non-equilibrium superconducting
effects. These effects are discussed from the experimental point of view

</DOC>
<DOC>
<DOCNO> 116837 </DOCNO>
2.856-GHz Modulation of Conventional Triode Electron Gun


  For the generation of picosecond (< 100 ps) electron beam pulses, we studied
the RF modulation of a conventional triode electron gun. The feasibility study
for this scheme has been experimentally investigated by modulating a triode gun
of the Y-824 cathode-grid (KG) structure provided by the CPI Eimac, with
2.856-GHz pulsed RF generated by a solid-state amplifier (SSA). In this paper,
we present the methods and results of this investigation.

</DOC>
<DOC>
<DOCNO> 69065 </DOCNO>
Off-forward gluonometry


  We explore the deeply virtual Compton scattering process at NLO with the
emphasis on the measurement of the tensor gluon skewed distributions. We
recalculate the one-loop coefficient function and give two-loop results for
anomalous dimensions and exclusive evolution kernels required for studying the
logarithmic scaling violation. We evaluate weighted cross sections which give
direct access to these functions on experiment.

</DOC>
<DOC>
<DOCNO> 102605 </DOCNO>
Homological Mirror Symmetry in Dimension One


  In this paper we complete the proof began by A. Polishchuk and E. Zaslow
(math.AG/9801119) of a weak version of Kontsevich's homological mirror symmetry
conjecture for elliptic curves. The main difference to the work of Polishchuk
and Zaslow is that we consider morphisms between any pair of objects, not only
in the transversal case. This enables us to show the conjectured equivalence of
categories.

</DOC>
<DOC>
<DOCNO> 13273 </DOCNO>
Harmonics generation in electron-ion collisions in a short laser pulse


  Anomalously high generation efficiency of coherent higher field-harmonics in
collisions between {\em oppositely charged particles} in the field of
femtosecond lasers is predicted. This is based on rigorous numerical solutions
of a quantum kinetic equation for dense laser plasmas which overcomes
limitations of previous investigations.

</DOC>
<DOC>
<DOCNO> 71801 </DOCNO>
Hadronic Corrections at O(alpha^2) to the Energy Spectrum of Muon Decay


  We consider the impact of O(alpha^2) hadronic corrections to the energy
spectrum of the decay electron in muon decay. We find that the correction can
be described, within good approximation, by a linear function in the electron
energy. Explicit expressions for the form factors needed in an approach based
on dispersion integrals are given.

</DOC>
<DOC>
<DOCNO> 169763 </DOCNO>
Structure of the Algebra of Effective Observables in Quantum Mechanics


  A subclass of dynamical semigroups induced by the interaction of a quantum
system with an environment is introduced. Such semigroups lead to the selection
of a stable subalgebra of effective observables. The structure of this
subalgebra is completely determined.

</DOC>
<DOC>
<DOCNO> 10956 </DOCNO>
An RVB phase in the triangular lattice quantum dimer model


  We study the quantum dimer model on the triangular lattice, which is expected
to describe the singlet dynamics of frustrated Heisenberg models in phases
where valence bond configurations dominate their physics. We find, in contrast
to the square lattice, that there is a truly short ranged resonating valence
bond (RVB) phase with no gapless collective excitations and with deconfined,
gapped, spinons for a {\it finite} range of parameters. We also establish the
presence of three crystalline phases in this system.

</DOC>
<DOC>
<DOCNO> 151093 </DOCNO>
Supersymmetric configurations in Euclidean Freedman-Schwarz model


  We study Euclidean D=4, N=4 gauged $SU(2) \times SU(1,1)$ supergravity theory
which has been obtained from dimensional reduction of N=1, D=10 supergravity on
$S^3 \times AdS_3$. We obtain supersymmetric configurations like domain wall,
electro-vac type of solutions with geometries $E^2 \times S^2$, $E^2 \times
AdS_2$ and axio-vac type $E^1 \times S^3$ solution in this Euclidean
Freedman-Schwarz (EFS) model. We also show that the Euclidean gravitational
instantons with nontrivial (anti)self-dual U(1) gauge fields are stable vacua
preserving one fourth of the original supersymmetry.

</DOC>
<DOC>
<DOCNO> 150947 </DOCNO>
Thermodynamical Behaviour of Composite Stringy Black Holes


  We study the thermodynamical and geometrical behaviour of the black holes
that arise as solutions of the heterotic string action. We discuss the
near-horizon scaling behaviour of the solutions that are described by
two-dimensional Anti-de Sitter Space AdS(2). We find that finite-energy
excitations of AdS(2) are suppressed only for scaling limits characterised by a
dilaton which is constant near the horizon, whereas this suppression does not
occur when the dilaton is non constant.

</DOC>
<DOC>
<DOCNO> 178724 </DOCNO>
SU(2) Chiral sigma model and the properties of neutron stars


  We discuss the {\it SU}(2) chiral sigma model in the context of nuclear
matter using a mean field approach at high density. In this model we include a
dynamically generated isoscalar vector field and higher-order terms in the
scalar field. With the inclusion of these, we reproduce the empirical values of
the nuclear matter saturation density, binding energy, and nuclear
incompressibility. The value of the incompressibility is chosen according to
recently obtained heavy-ion collision data. We then apply the same dynamical
model to neutron-rich matter in beta equilibrium, related to neutron star
structure. The maximum mass and corresponding radius of stable non-rotating
neutron stars are found to be in the observational limit.

</DOC>
<DOC>
<DOCNO> 84495 </DOCNO>
Brane World Cosmology - Gauge-Invariant Formalism for Perturbation


  In the present paper the gauge-invariant formalism is developed for
perturbations of the brane-world model in which our universe is realized as a
boundary of a higher-dimensional spacetime. For the background model in which
the bulk spacetime is $(n+m)$-dimensional and has the spatial symmetry
corresponding to the isometry group of a $n$-dimensional maximally symmetric
space, gauge-invariant equations are derived for perturbations of the bulk
spacetime. Further for the case corresponding to the brane-world model in which
$m=2$ and the brane is a boundary invariant under the spatial symmetry in the
unperturbed background, relations between the gauge-invariant variables
describing the bulk perturbations and those for brane perturbations are derived
from Israel's junction condition under the assumption of $\ZR_2$ symmetry. In
particular, for the case in which the bulk spacetime is a constant-curvature
spacetime, it is shown that the bulk perturbation equations reduce to a single
hyperbolic master equation for a master variable, and that the physical
condition on the gauge-invariant variable describing the intrinsic stress
perturbation of the brane yield a boundary condition for the master equation
through the junction condition. On the basis of this formalism it is pointed
out that it seems to be difficult to suppress brane perturbations corresponding
to massive excitations for a brane motion giving a realistic expanding universe
model.

</DOC>
<DOC>
<DOCNO> 121603 </DOCNO>
Far Ultraviolet Imagery of the Edge-On Spiral Galaxy NGC 4631


  Far ultraviolet FUV imagery of the edge-on, Sc/SBd galaxy, NGC 4631 reveals
very strong FUV emission, resulting from active star formation, uniformly
distributed along the galactic mid- plane. Multi-band imagery, HI and HII
position-velocity curves and extinction considerations all imply that the
emission is from the outer edges of the visible galaxy. The overall FUV
morphology of this edge-on disk system is remarkably similar to those of the
so-called "chain galaxies" evident at high redshift, thus suggesting a similar
interpretation for at least some of those distant objects. FUV, U, B and V
magnitudes, measured for 48 star forming regions, along with corresponding
H-alpha and H-beta measurements are used to construct diagnostic color-color
diagrams. Although there are significant exceptions, most of the star forming
regions are less massive and older than 30 Doradus. Comparison with the
expectations from two star formation models yields ages of 2.7 to 10 Myr for
the instantaneous burst (IB) model and star formation cut-off ages of 0 to 9
Myr for the continuous star formation (CSF) model. Interpreted in terms of the
IB model the photometry implies a total created mass in the 48 star forming
regions of 25 million solar-masses. When viewed as resulting from constant star
formation the photometry implies a star formation rate of 0.33 solar-masses/yr.
These results are compared to those derived from FIR and radio observations.
Corrections for FUV emission reprocessed by interstellar grains are estimated.

</DOC>
<DOC>
<DOCNO> 8546 </DOCNO>
Origin of the Quasiparticle Peaks of Spectral Functions in High $T_c$


  Based on the SU(2) slave-boson approach to the t-J Hamiltonian, we examine
the cause of the sharp peaks('quasiparticle' peaks) in the observed spectral
functions in high $T_c$ cuprates. The computed results reveal that the spectral
weight of the sharp peaks increases with hole doping rate in agreement with
observation. It is shown that the observed sharp peaks are attributed to the
enhancement of spinon pairing(spin singlet pair formation) by the presence of
holon pair bosons in the superconducting state.

</DOC>
<DOC>
<DOCNO> 8646 </DOCNO>
High temperature superconductivity from the two-dimensional


  We examine the possibility of high temperature superconductivity from
two-dimensional semiconductor without antiferromagnetic fluctuations. The weak
coupling BCS theory is applied, especially where the Fermi level is near the
bottom of the conduction band. Due to screening, the attractive interaction is
local in k-space. The density of states(DOS) does not have a peak near the
bottom of the band, but k-dependent contribution to DOS has a diverging peak at
the bottom. These features lead to high temperature superconductivity which may
explain the possible superconductivity of WO_3.

</DOC>
<DOC>
<DOCNO> 119886 </DOCNO>
Reconstructing the ZOA from Galaxy Peculiar Velocities


  Galaxy peculiar velocity data provide important dynamical clues to the
structures obscured by the Zone of Avoidance (hereafter, ZOA) with resolution
>~ 500km/s. This indirect probe complements the very challenging approach of
directly mapping of the distribution of galaxies behind the Milky Way. In this
work, the Wiener filter method is applied to reconstruct the 3D density and
velocity distributions of the universe, within ~8000km/s, using SEcat the
largest peculiar velocity catalog yet. This catalog is a combination of the SFI
spiral galaxy peculiar velocity catalog and the newly completed nearby
early-type galaxy peculiar velocity catalog, ENEAR. The recovered density is
smoothed with 900km/s Gaussian. The main reconstructed structures are
consistent with those extracted from the IRAS 1.2-Jy redshift galaxy catalogs.
The revealed structures are identified and their robustness and significance
are discussed.

</DOC>
<DOC>
<DOCNO> 121085 </DOCNO>
AST/RO Observations of Atomic Carbon near the Galactic Center


  We present a coarsely-sampled map of the region |l|<=2 degrees, |b|<=0.1
degrees in the 492 GHz 3P1-->3P0 fine structure transition of neutral carbon,
observed with the Antarctic Submillimeter Telescope and Remote Observatory
(AST/RO). The distribution of C[I] emission is similar on the large scale to
that of CO J=1-->0. On average, the ratio of the integrated intensities, I_{C
I}/I_{12CO}, is higher in the Galactic disk than in the Galactic Center region.
This result is accounted for by the absorption of 12CO within the clouds
located in the outer Galactic disk. I_{C I}/I_{12CO} is surprisingly uniform
over the variety of environments near the Galactic Center. On average, C[I] is
optically thin (or as optically thin as 13CO(J=1-->0)) even in the dense
molecular clouds of the Galactic Center region.

</DOC>
<DOC>
<DOCNO> 8471 </DOCNO>
Finite-size calculations of spin-lattice relaxation rates in Heisenberg


  Calculations of nuclear spin-lattice relaxation rates are carried out by
means of exact diagonalization on small (2 x 6) antiferromagnetic Heisenberg
ladders, using the simplest forms permitted by symmetry for the hyperfine
couplings for the three nuclear sites in Cu2O3 ladders. Several values of the
rung/chain exchange ratio have been considered. Comparisons with experimental
results, field theoretic calculations, and the Gaussian approximation highlight
some open problems.

</DOC>
<DOC>
<DOCNO> 121361 </DOCNO>
The cosmological evolution of BL Lacs: The REX point of view


  We present the results on the cosmological evolution of BL Lac objects as
derived from a statistically complete sample of 44 BL Lacs selected from the
X-ray bright tail of the REX survey. With this sample, we have investigated the
cosmological properties of BL Lacs taking into account the radio, optical and
X-ray limits. We infer that no evolution is clearly visible down to the flux
limits reached by our sample. On the other hand, deeper samples are probably
needed in order to detect the negative evolution found in the EMSS sample. The
identification of such deeper sample, extracted from the REX survey, is in
progress.

</DOC>
<DOC>
<DOCNO> 71882 </DOCNO>
Yukawa Textures in Heterotic M-Theory


  We examine the structure of the Yukawa couplings in the 11 dimensional
Horava-Witten M-theory based on non-standard embeddings. We find that the CKM
and quark mass hierarchies can be explained in M Theory without introducing
undue fine tuning. A phenomenological example is presented satisfying all CKM
and quark mass data requiring the 5-branes cluster near the second orbifold
plane, and that the instanton charges of the physical orbifold plane vanish.
The latter condition is explicitly realized on a Calabi-Yau manifold with del
Pezzo base dP_7.

</DOC>
<DOC>
<DOCNO> 122870 </DOCNO>
Exploring the formation and evolution of massive ellipticals with


  Extremely Red Objects (EROs) provide the important possibility to shed light
on the formation and evolution of the present-day massive ellipticals. On one
hand, they allow to select z>1 old passively evolving spheroidals and to
compare their abundance with the predictions of galaxy formation scenarios. On
the other hand, they provide the possibility to find dust obscured starbursts,
a fraction of which may trace the formation of proto-ellipticals at z>2. In
this paper, the most recent results on EROs are reviewed and the main
implications discussed.

</DOC>
<DOC>
<DOCNO> 12043 </DOCNO>
Correlation Functions and Corner Transfer Matrix of the Chiral Potts


  We use the Density Matrix Renormalization Group technique to compute
correlation functions of the Z_3-chiral Potts quantum chain in the massive
regimes. Chains of up to 70 sites are used and a clear oscillatory behavior is
found. We also check the relation between the density matrix spectrum and the
Corner Transfer Matrix spectrum pointed out by Nishino and Okunishi, using
Baxter's low-temperature formulae for the chiral Potts Corner Transfer Matrix
eigenvalues. We find very good agreement.

</DOC>
<DOC>
<DOCNO> 170812 </DOCNO>
Landau Levels in the Presence of Topological Defects


  We study the Landau levels associated with electrons moving in a magnetic
field in the presence of a continuous distribution of disclinations, a magnetic
screw dislocation and a dispiration. We focus on the influence of these
topological defects on the spectrum of the electron(or hole) in a magnetic
field in the framework of the geometric theory of defects in solids of Katanaev
and Volovich. The presence of the defects breaks the degeneracy of the Landau
levels in different ways depending on the defect. Exact expressions for
energies and eigenfuctions are found for all cases.

</DOC>
<DOC>
<DOCNO> 71049 </DOCNO>
Applications of non-perturbative renormalization


  A short survey of the renormalization problem in QCD and its non-perturbative
solution by means of numerical simulations on the lattice is given. Most
emphasis is on scale dependent renormalizations, which can be reliably
addressed via a recursive finite-size scaling procedure employing a suitable
intermediate renormalization scheme. To illustrate these concepts we discuss
some - partly recent - computations of phenomenologically relevant quantities:
the running QCD gauge coupling, renormalization group invariant quark masses
and the renormalization of the static-light axial current.

</DOC>
<DOC>
<DOCNO> 117612 </DOCNO>
The X-ray Properties of z>4 Quasars


  We report on a search for X-ray emission from quasars with redshifts greater
than four using the ROSAT public database. Our search has doubled the number of
z>4 quasars detected in X-rays from 6 to 12. Most of those known prior to this
work were radio-loud and X-ray selected sources; our study increases the number
of X-ray detected, optically selected z>4 quasars from one to seven. We present
their basic X-ray properties and compare these to those of lower redshift
quasars. We do not find any evidence for strong broad-band spectral differences
between optically selected z>4 quasars and those at lower redshifts.

</DOC>
<DOC>
<DOCNO> 11480 </DOCNO>
Bose-Einstein condensation in shallow traps


  In this paper we study the properties of Bose-Einstein condensates in shallow
traps. We discuss the case of a Gaussian potential, but many of our results
apply also to the traps having a small quadratic anharmonicity. We show the
errors introduced when a Gaussian potential is approximated with a parabolic
potential, these errors can be quite large for realistic optical trap parameter
values. We study the behavior of the condensate fraction as a function of trap
depth and temperature and calculate the chemical potential of the condensate in
a Gaussian trap. Finally we calculate the frequencies of the collective
excitations in shallow spherically symmetric and 1D traps.

</DOC>
<DOC>
<DOCNO> 39873 </DOCNO>
No CPT Violation from Tilted Brane in Neutral Meson--Antimeson Systems


  Tilted brane in theories with large compact extra dimensions leads to
spontaneous symmetry breaking of the Lorentz and rotational invariance in four
dimensions, as shown by Dvali and Shifman. In this brief report, we point out
that the mentioned Lorentz symmetry breaking, although leading to the
CPT--violating interaction terms, cannot lead to the CPT violation in the
experimentally interesting $K$--${\bar K}$ and analogous systems.

</DOC>
<DOC>
<DOCNO> 178497 </DOCNO>
How unique is the Asymptotic Normalisation Coefficient (ANC) method?


  The asymptotic normalisation coefficients (ANC) for the vertex $^{10}$B $\to$
$^9$Be + p is deduced from a set of different proton transfer reactions at
different energies. This set should ensure the peripheral character of the
reaction and availability of data for the elastic channels. The problems
associated with the characteristics of the data and the analysis are discussed.
For a subgroup of the set of available data, the uniqueness property of the
extracted ANC is fulfilled. However, more measurements are needed before a
definite conclusion can be drawn.

</DOC>
<DOC>
<DOCNO> 102103 </DOCNO>
Homology cylinders: an enlargement of the mapping class group


  We consider a homological enlargement of the mapping class group, defined by
homology cylinders over a closed oriented surface (up to homology cobordism).
These are important model objects in the recent Goussarov-Habiro theory of
finite-type invariants of 3-manifolds.
  We study the structure of this group from several directions: the relative
weight filtration of Dennis Johnson, the finite-type filtration of
Goussarov-Habiro, and the relation to string link concordance.
  We also consider a new Lagrangian filtration of both the mapping class group
and the group of homology cylinders.

</DOC>
<DOC>
<DOCNO> 116293 </DOCNO>
New tests for a singularity of ideal MHD


  Analysis using new calculations with 3 times the resolution of the earlier
linked magnetic flux tubes confirms the transition from singular to saturated
growth rate reported by Grauer and Marliani \cite{GrauerMar99} for the
incompressible cases is confirmed. However, all of the secondary tests point to
a transition back to stronger growth rate at a different location at late
times. Similar problems in ideal hydrodynamics are discussed, pointing out that
initial negative results eventually led to better initial conditions that did
show evidence for a singularity of Euler. Whether singular or near-singular
growth in ideal MHD is eventually shown, this study could have bearing on fast
magnetic reconnection, high energy particle production and coronal heating.

</DOC>
<DOC>
<DOCNO> 122278 </DOCNO>
Large Scale Structure


  Catalogues of galaxies, clusters of galaxies and superclusters - sources of
information to study the large-scale structure of the Universe are reviewed.
The power spectrum of density perturbations, and the correlation function are
discussed as principal description functions which characterize the large-scale
structure. Special attention is payd to the geometric interpretation of these
functions, i.e. the way in which the various properties of the distribution of
galaxies in systems and systems themselves are reflected in these functions. We
discuss cosmological parameters which characterize general properties of the
Universe: the Hubble constant, densities of various populations of the
Universe, and parameters of the power spectrum of galaxies and matter.

</DOC>
<DOC>
<DOCNO> 100047 </DOCNO>
The regular representations and the $A_{n}(V)$ algebras


  For a vertex operator algebra $V$, the regular representations are related to
the $A_{n}(V)$-algebras and their bimodules, and induced $V$-modules from
$A_{n}(V)$-modules are defined and studied in terms of the regular
representations.

</DOC>
<DOC>
<DOCNO> 8877 </DOCNO>
Topological Evolution of Dynamical Networks: Global Criticality from


  We evolve network topology of an asymmetrically connected threshold network
by a simple local rewiring rule: quiet nodes grow links, active nodes lose
links. This leads to convergence of the average connectivity of the network
towards the critical value $K_c =2$ in the limit of large system size $N$. How
this principle could generate self-organization in natural complex systems is
discussed for two examples: neural networks and regulatory networks in the
genome.

</DOC>
<DOC>
<DOCNO> 7745 </DOCNO>
First Dark Matter Limits from a Large-Mass, Low-Background Superheated


  We report on the fabrication aspects and calibration of the first large
active mass ($\sim15$ g) modules of SIMPLE, a search for particle dark matter
using Superheated Droplet Detectors (SDDs). While still limited by the
statistical uncertainty of the small data sample on hand, the first weeks of
operation in the new underground laboratory of Rustrel-Pays d'Apt already
provide a sensitivity to axially-coupled Weakly Interacting Massive Particles
(WIMPs) competitive with leading experiments, confirming SDDs as a convenient,
low-cost alternative for WIMP detection.

</DOC>
<DOC>
<DOCNO> 101868 </DOCNO>
Statistical properties of unimodal maps: the quadratic family


  We prove that almost every real quadratic map is either regular or
Collet-Eckmann with polynomial recurrence of the critical orbit. It follows
that typical quadratic maps have excellent ergodic properties, as exponential
decay of correlations (Keller and Nowicki, Young) and stochastic stability in
the strong sense (Baladi and Viana). This is an important step to get the same
results for more general families of unimodal maps.

</DOC>
<DOC>
<DOCNO> 121777 </DOCNO>
Calibrations of alpha Cen A & B


  Detailed evolutionary models of the visual binary alpha Centauri, including
pre main-sequence evolution, have been performed using the masses recently
determined by Pourbaix et al. (1999). Models have been constructed using the
CEFF equation of state, OPAL opacities, NACRE thermonuclear reaction rates and
microscopic diffusion. A chi^2-minimization is performed to derive the most
reliable set of modeling parameters wp={t_alpha Cen, Yi, [Fe/H]i, alpha A,
alpha B}, where t alpha Cen is the age of the system, Yi the initial helium
content, [Fe/H]i the initial metallicity and, alpha A and alpha B the
convection parameters of the two components. Using the basic Bohm-Vitense
(1958) mixing-length theory of convection, we derive wp BV={2710 Myr,
0.284,0.257, 1.53, 1.57}. We obtain a noticeably smaller age than estimated
previously, in agreement with Pourbaix et al. (1999), mainly because of the
larger masses. If convective core overshoot is considered we get wp ov={3530
Myr, 0.279,0.264,1.64,1.66}. The use of Canuto & Mazitelli (1991, 1992)
convection theory leads to the set wp CM={4086 Myr, 0.271, 0.264, 0.964,
0.986}. Using the observational constraints adopted by Guenther & Demarque
(2000), and the basic mixing-length theory, we obtain wp GD={5640 Myr, 0.300,
0.296, 1.86, 1.97} and surface lithium depletions close to their observed
values.
  A seismological analysis of our calibrated models has been performed. The
determination of large and small spacings between the frequencies of acoustic
oscillations from seismic observations would help to discriminate between the
models of alpha Cen computed with different masses and to confirm or rules out
the new determination of masses.

</DOC>
<DOC>
<DOCNO> 170124 </DOCNO>
Entanglement, Information and Multiparticle Quantum Operations


  Collective operations on a network of spatially-separated quantum systems can
be carried out using local quantum (LQ) operations, classical communication
(CC) and shared entanglement (SE). Such operations can also be used to
communicate classical information and establish entanglement between distant
parties. We show how these facts lead to measures of the inseparability of
quantum operations, and argue that a maximally-inseparable operation on 2
qubits is the SWAP operation. The generalisation of our argument to N qubit
operations leads to the conclusion that permutation operations are
maximally-inseparable. For even N, we find the minimum SE and CC resources
which are sufficient to perform an arbitrary collective operation. These
minimum resources are 2(N-1) ebits and 4(N-1) bits, and these limits can be
attained using a simple teleportation-based protocol. We also obtain lower
bounds on the minimum resources for the odd case. For all $N{\geq}4$, we show
that the SE/CC resources required to perform an arbitrary operation are
strictly greater than those that any operation can establish/communicate.

</DOC>
<DOC>
<DOCNO> 150456 </DOCNO>
Noncommutative and Ordinary Super Yang-Mills on (D$(p-2)$, D$p$) Bound


  We study properties of (D$(p-2)$, D$p$) nonthreshold bound states ($2 \le p
\le 6 $) in the dual gravity description. These bound states can be viewed as
D$p$-branes with a nonzero NS $B$ field of rank two. We find that in the
decoupling limit, the thermodynamics of the $N_p$ coincident D$p$-branes with
$B$ field is the same not only as that of $N_p$ coincident D$p$-branes without
$B$ field, but also as that of the $N_{p-2}$ coincident D$(p-2)$-branes with
two smeared coordinates and no $B$ field, for $N_{p-2}/N_p=
\tilde{V}_2/[(2\pi)^2 \tilde{b}]$ with $\tilde{V}_2$ being the area of the two
smeared directions and $\tilde{b}$ a noncommutativity parameter. We also obtain
the same relation from the thermodynamics and dynamics by probe methods. This
suggests that the noncommutative super Yang-Mills with gauge group $U(N_p)$ in
($p+1$) dimensions is equivalent to an ordinary one with gauge group
$U(\infty)$ in ($p-1$) dimensions in the limit $\tilde{V}_2 \to \infty$. We
also find that the free energy of a D$p$-brane probe with $B$ field in the
background of D$p$-branes with $B$ field coincides with that of a D$p$-brane
probe in the background of D$p$-branes without $B$ field.

</DOC>
<DOC>
<DOCNO> 14160 </DOCNO>
Empirical Calculations of the Formation Energies of Intrinsic Defects in


  Results of our shell-model calculations concerning the determination of
empirical parameters of inter-ionic potentials and the formation energies of
point defects in LiNbO3 are presented. We employed the relaxed fitting method
which is particularly appropriate for the modeling of low-symmetry structure.
Attention is paid to guarantee the simulation precision of the parameters who
are sensitive for defect formation energy calculations. It is shown that Li
Frenkel disorders are the main intrinsic defects in stoichiometric lithium
niobate and Li vacancy model is the dominant defect species in congruent
lithium niobate.

</DOC>
<DOC>
<DOCNO> 10242 </DOCNO>
Nonequilibrium Quantum Dynamics of Second Order Phase Transitions


  We use the so-called Liouville-von Neumann (LvN) approach to study the
nonequilibrium quantum dynamics of time-dependent second order phase
transitions. The LvN approach is a canonical method that unifies the functional
Schr\"{o}dinger equation for the quantum evolution of pure states and the LvN
equation for the quantum description of mixed states of either equilibrium or
nonequilibrium. As nonequilibrium quantum mechanical systems we study a
time-dependent harmonic and an anharmonic oscillator and find the exact Fock
space and density operator for the harmonic oscillator and the nonperturbative
Gaussian Fock space and density operator for the anharmonic oscillator. The
density matrix and the coherent, thermal and coherent-thermal states are found
in terms of their classical solutions, for which the effective Hamiltonians and
equations of motion are derived. The LvN approach is further extended to
quantum fields undergoing time-dependent second order phase transitions. We
study an exactly solvable model with a finite smooth quench and find the
two-point correlation functions. Due to the spinodal instability of long
wavelength modes the two-point correlation functions lead to the
$t^{1/4}$-scaling relation during the quench and the Cahn-Allen scaling
relation $t^{1/2}$ after the completion of quench. Further, after the finite
quench the domain formation shows a time-lag behavior at the cubic power of
quench period. Finally we study the time-dependent phase transition of a
self-interacting scalar field.

</DOC>
<DOC>
<DOCNO> 72154 </DOCNO>
Polarization in Hadronic \Lambda Hyperon Production and Chiral-Odd


  Polarization of the \Lambda hyperon produced with a large transverse momentum
in the unpolarized nucleon-nucleon collision is analyzed in the framework of
QCD factorization. We focus on the mechanism in which the soft-gluon component
of the chiral-odd spin-independent twist-3 quark distribution E_F(x,x) becomes
a source of the polarized quark fragmenting into the polarized \Lambda. Our
simple model estimate for this contribution indicates that it gives rise to a
significant \Lambda polarization at large x_F. This is in parallel with the
observation that the soft gluon pole mechanism gives rise to a large single
transverse spin asymmetry in the pion production at x_F\to 1.

</DOC>
<DOC>
<DOCNO> 118811 </DOCNO>
Coupling of the X-ray and radio emission in the black hole candidate a


  We report the results of a long-term campaign of radio, soft- and hard- X-ray
observations of the galactic black hole candidate GX 339-4. In the Low-Hard
X-ray state the system displays a strong 3-way linear correlation between soft-
and hard-X-rays and radio emission, implying a coupling between the
Comptonising corona and a radio-emitting compact jet. In this state the radio
emission is linearly polarised at a level of around 2 %, with an almost
constant polarisation angle, indicative of a favored axis in this system
probably related to the compact jet and/or black hole spin axis. In the Off
X-ray state the radio emission declines with the X-ray emission to below
detectable levels, suggesting that it is simply a lower-luminosity version of
the Low-Hard state. In the High-Soft state both the hard-X-ray and radio
emission are suppressed. We also note that the transitions from the Low-Hard
state to the High-Soft state (and the reverse) are possibly associated with
discrete ejection(s) of expanding relativistic plasma.

</DOC>
<DOC>
<DOCNO> 13943 </DOCNO>
Against temperature chaos in naive Thouless-Anderson-Palmer equations


  We study the temperature structure of the naive TAP equations by mean of a
recursion algorithm. The problem of the chaos in temperature is addressed using
the notion of the temperature evolution of equilibrium states. The lowest free
energy states show relevant correlations with the ground state, and a careful
finite size analysis indicates that these correlations are not finite size
effects, ruling out the possibility of chaos in temperature even in the
thermodynamic limit. The correlations of the equilibrium states with respect to
the ground state are investigated. The performance of a new heuristic algorithm
for the search of ground states is also discussed.

</DOC>
<DOC>
<DOCNO> 83300 </DOCNO>
Phase Clocks for Transient Fault Repair


  Phase clocks are synchronization tools that implement a form of logical time
in distributed systems. For systems tolerating transient faults by self-repair
of damaged data, phase clocks can enable reasoning about the progress of
distributed repair procedures. This paper presents a phase clock algorithm
suited to the model of transient memory faults in asynchronous systems with
read/write registers. The algorithm is self-stabilizing and guarantees accuracy
of phase clocks within O(k) time following an initial state that is k-faulty.
Composition theorems show how the algorithm can be used for the timing of
distributed procedures that repair system outputs.

</DOC>
<DOC>
<DOCNO> 70762 </DOCNO>
Breathing mode compactifications and supersymmetry of the brane-world


  It has recently been shown that the Randall-Sundrum brane-world may be
obtained from an appropriate doubled D3-brane configuration in type IIB theory.
This corresponds, in five dimensions, to a sphere compactification of the
original IIB theory with a non-trivial breathing mode supporting the brane. In
this paper, we shall study the supersymmetry of this reduction to massive
five-dimensional supergravity, and derive the effective supersymmetry
transformations for the fermionic superpartners to the breathing mode. We also
consider the sphere compactifications of eleven-dimensional supergravity to
both four and seven dimensions. For the compactifications on S^5 and S^7, we
include a squashing mode scalar and discuss the truncation from N=8 to N=2
supersymmetry.

</DOC>
<DOC>
<DOCNO> 99435 </DOCNO>
Local Cohomology at Monomial Ideals


  For a reduced monomial ideal B in R=k[X_1,...,X_n], we write H^i_B(R) as the
union of {Ext^i(R/B^[d],R)}_d, where {B^[d]}_d are the "Frobenius powers of B".
We describe H^i_B(R)_p, for every p in Z^n, in the spirit of the
Stanley-Reisner theory. As a first application we give an isomorphism Tor_i(B',
k)_p\iso Ext^{|p|-i}(R/B,R)_{-p} for all p in {0,1}^n, where B' is the
Alexander dual ideal of B. We deduce a canonical filtration of Ext^i(R/B,R)
with succesive quotients of the form R/(X_{j_1},...,X_{j_i}) suitably shifted,
the multiplicities being computed from the Betti numbers of B'. As a final
application, we give a topological description for the associated primes of
Ext^i(R/B,R).

</DOC>
<DOC>
<DOCNO> 40044 </DOCNO>
B->D*pi+pi-pi-pio, D(*) omega pi- and the Observation of a Wide 1- omega


  We report on the observation of B->D{*}pi+pi-pi-pio decays. The branching
ratios for D*+ and D*o are (1.72+/-0.14+/-0.24)% and (1.80+/-0.24+/-0.25)%,
respectively. Each final state has a D{*} omega pi- component, with branching
ratios (0.29+/-0.03+/-0.04)% and (0.45+/-0.10+/-0.07)% for the D*+ and D*o
modes, respectively. We also observe B->D omega pi- decays. The branching
ratios for D+ and Do are (0.28+/-0.05+/-0.03)% and (0.41+/-0.07+/-0.04)%,
respectively. The omega pi- appears to come from the decay of a wide 1-
resonance. A fit to a Breit-Wigner shape gives a mass of 1418+/-26+/-19 MeV and
width of 388+/-44+/-32 MeV. We identify this object as the rho(1450) or rho'.

</DOC>
<DOC>
<DOCNO> 69654 </DOCNO>
On the Role of Energy Conservation in High-Energy Nuclear Scattering


  We argue that most commonly used models for nuclear scattering at
ultra-relativistic energies do not treat energy conservation in a consistent
fashion. Demanding theoretical consistency as a minimal requirement for a
realistic model, we provide a solution for the above-mentioned problem, the
so-called ``Parton-Based Gribov-Regge Theory''. In order to keep a clean
picture, we do not consider secondary interactions. We provide a very
transparent extrapolation of the physics of more elementary interactions
towards nucleus-nucleus scattering, without considering any nuclear effects due
to final state interactions. In this sense we consider our model a realistic
and consistent approach to describe the initial stage of nuclear collisions.

</DOC>
<DOC>
<DOCNO> 100063 </DOCNO>
A generalization of Hagopian's theorem and exponents


  We generalize Hagopian's theorem characterizing solenoids to higher
dimensions by showing that any homogeneous continuum admitting a fiber bundle
projection onto a torus with totally disconnected fibers admits a compatible
abelian topological group structure. The higher dimensional exponent group is
then introduced.

</DOC>
<DOC>
<DOCNO> 12617 </DOCNO>
A mode-coupling theory for the glassy dynamics of a diatomic probe


  Generalizing the mode-coupling theory for ideal liquid-glass transitions,
equations of motion are derived for the correlation functions describing the
glassy dynamics of a diatomic probe molecule immersed in a simple glass-forming
system. The molecule is described in the interaction-site representation and
the equations are solved for a dumbbell molecule consisting of two fused hard
spheres in a hard-sphere system. The results for the molecule's arrested
position in the glass state and the reorientational correlators for
angular-momentum index $\ell = 1$ and $\ell = 2$ near the glass transition are
compared with those obtained previously within a theory based on a
tensor-density description of the molecule in order to demonstrate that the two
approaches yield equivalent results. For strongly hindered reorientational
motion, the dipole-relaxation spectra for the $\alpha$-process can be mapped on
the dielectric-loss spectra of glycerol if a rescaling is performed according
to a suggestion by Dixon et al. [Phys. Rev. Lett. {\bf 65}, 1108 (1990)]. It is
demonstrated that the glassy dynamics is independent of the molecule's inertia
parameters.

</DOC>
<DOC>
<DOCNO> 100210 </DOCNO>
On Nichols algebras of low dimension


  This is a contribution to the classification program of pointed Hopf
algebras. We give a generalization of the quantum Serre relations and propose a
generalization of the Frobenius-Lusztig kernels in order to compute Nichols
algebras of diagonal group type. With this, we classify Nichols algebras B(V)
with dimension < 32 or with dimension p^3, p a prime number, when V lies in a
Yetter-Drinfeld category over a finite group. With the so called Lifting
Procedure, this allows to classify pointed Hopf algebras of index < 32 or p^3.
  In recent articles by Etingof-Schedler-Soloviev and Lu-Yan-Zhu, the authors
deal with set-theoretical solutions to the Braid Equation. We propose here an
homology theory for conjugate solutions (in the language of Lu-Yan-Zhu) which
parameterizes usual solutions lying over set-theoretical conjugate ones. These
usual solutions are modules in Yetter-Drinfeld categories over group algebras,
and then they provide (after computing Nichols algebras and liftings of their
bosonizations) families of pointed Hopf algebras.

</DOC>
<DOC>
<DOCNO> 11557 </DOCNO>
Comment on "Theory of diluted magnetic semiconductor ferromagnetism"


  In this comment, we emphasize that the self-consistent spin wave theory in a
recent paper [J. K"onig, H.-H. Lin, and A. H. MacDonald, Phys. Rev. Lett. 84,
5628 (2000)] leads to incorrect results both at low temperatures and near T_c.
Thus we suggest another self-consistent spin wave approximation to remedy these
flaws.

</DOC>
<DOC>
<DOCNO> 84962 </DOCNO>
Lagrangian formalism for tensor fields


  The Lagrangian formalism for tensor fields over differentiable manifolds with
contravariant and covariant affine connections (whose components differ not
only by sign) and metrics [$(\bar{L}_n,g)$-spaces] is considered. The
functional variation and the Lie variation of a Lagrangian density, depending
on components of tensor fields (with finite rank) and their first and second
covariant derivatives are established. A variation operator is determined and
the corollaries of its commutation relations with the covariant and the Lie
differential operators are found. The canonical (common) method of Lagrangians
with partial derivatives (MLPD) and the method of Lagrangians with covariant
derivatives (MLCD) are outlined. They differ from each other by the commutation
relations the variation operator has to obey with the covariant and the Lie
differential operator. The canonical and covariant Euler-Lagrange equations are
found as well as their corresponding $(\bar{L}_n,g)$-spaces. The
energy-momentum tensors are considered on the basis of the Lie variation and
the covariant Noether identities.

</DOC>
<DOC>
<DOCNO> 169731 </DOCNO>
Prospects for photon blockade in four level systems in the N


  We show that for appropriate choices of parameters it is possible to achieve
photon blockade in idealised one, two and three atom systems. We also include
realistic parameter ranges for rubidium as the atomic species. Our results
circumvent the doubts cast by recent discussion in the literature (Grangier et
al Phys. Rev Lett. 81, 2833 (1998), Imamoglu et al Phys. Rev. Lett. 81, 2836
(1998)) on the possibility of photon blockade in multi-atom systems.

</DOC>
<DOC>
<DOCNO> 84140 </DOCNO>
Can one increase the luminosity of a Schwarzschild black hole?


  We illustrate how Hawking's radiance from a Schwarzschild black hole is
modified by the electrostatic self-interaction of the emitted charged
particles. A W.K.B approximation shows that the probability for a
self-interacting charged particle to propagate from the interior to the
exterior of the horizon is increased relative to the corresponding probability
for neutral particles. We also demonstrate how the electric potential of a
charged test object in the black hole's vicinity gives rise to pair creation.
We analyze this phenomenon semiclassically by considering the existence of the
appropriate Klein region. Finally we discuss the possible energy source for the
process.

</DOC>
<DOC>
<DOCNO> 11810 </DOCNO>
Interplay between proton ordering and ferroelectric polarization in


  The origin of ferroelectricity in KH_2PO_4 (KDP) is studied by
first-principles electronic structure calculations. In the low-temperature
phase, the collective off-center ordering of the protons is accompanied by an
electronic charge delocalization from the "near" and localization at the "far"
oxygen within the O-H...O bonds. Electrostatic forces, then, push the K+ ions
towards off-center positions, and induce a macroscopic polarization. The
analysis of the correlation between different geometrical and electronic
quantities, in connection with experimental data, supports the idea that the
role of tunnelling in isotopic effects is irrelevant. Instead, geometrical
quantum effects appear to play a central role.

</DOC>
<DOC>
<DOCNO> 8012 </DOCNO>
Epitaxy and magnetotransport of Sr_2FeMoO_6 thin films


  By pulsed-laser deposition epitaxial thin films of Sr_2FeMoO_6 have been pre-
pared on (100) SrTiO_3 substrates. Already for a deposition temperature of 320
C epitaxial growth is achieved. Depending on deposition parameters the films
show metallic or semiconducting behavior. At high (low) deposition temperature
the Fe,Mo sublattice has a rock-salt (random) structure. The metallic samples
have a large negative magnetoresistance which peaks at the Curie temperature.
The magnetic moment was determined to 4 mu_B per formula unit (f.u.), in
agreement with the expected value for an ideal ferrimagnetic arrangement. We
found an ordinary Hall coefficient of -6.01x10^{-10} m^3/As at 300 K,
corresponding to an electronlike charge-carrier density of 1.3 per Fe,Mo-pair.
In the semiconducting films the magnetic moment is reduced to 1 mu_B/f.u. due
to disorder in the Fe,Mo sublattice. In low fields an anomalous holelike
contribution dominates the Hall voltage, which vanishes at low temperatures for
the metallic films only.

</DOC>
<DOC>
<DOCNO> 10316 </DOCNO>
Pin-Hole Water Flow from Cylindrical Bottles


  We performed an experiment on elementary hydrodynamics. The basic system is a
cylindrical bottle from which water flows through a pin-hole located at the
bottom of its lateral surface. We measured the speed of the water leaving the
pin-hole, as a function of both the time and the current level of water still
inside the bottle. The experimental results are compared with the theory. The
theoretical treatment is a very simple one based on mass and energy
conservation, corresponding to a widespread exercise usually adopted in
university basic disciplines of Physics.
  We extended the previous experiment to another similar system using two equal
bottles with equal pin-holes. The water flowing from the first bottle feeds the
second one located below it. The same concepts of mass and energy conservation
now lead to a non-trivial differential equation for the lowest bottle dynamics.
We solved this equation both numerically and analytically, comparing the
results with the experimental data.

</DOC>
<DOC>
<DOCNO> 70792 </DOCNO>
Vacuum polarization in thermal QED with an external magnetic field


  The one-loop vacuum polarization tensor is computed in QED with an external
constant, homogeneous magnetic field at finite temperature. The Schwinger
proper-time formalism is used and the computations are done in Euclidian space.
The well-known results are recovered when the temperature and/or the magnetic
field are switched off and the effect of the magnetic field on the Debye
screening is discussed.

</DOC>
<DOC>
<DOCNO> 13034 </DOCNO>
The response function of a sphere in a viscoelastic two-fluid medium


  In order to address basic questions of importance to microrheology, we study
the dynamics of a rigid sphere embedded in a model viscoelastic medium
consisting of an elastic network permeated by a viscous fluid. We calculate the
complete response of a single bead in this medium to an external force and
compare the result to the commonly-accepted, generalized Stokes-Einstein
relation (GSER). We find that our response function is well approximated by the
GSER only within a particular frequency range determined by the material
parameters of both the bead and the network. We then discuss the relevance of
this result to recent experiments. Finally we discuss the approximations made
in our solution of the response function by comparing our results to the exact
solution for the response function of a bead in a viscous (Newtonian) fluid.

</DOC>
<DOC>
<DOCNO> 120581 </DOCNO>
The Shapley Supercluster. II. Spectroscopic observations in a wide area


  We report 2868 new multi-object spectroscopic measurements of galaxy
redshifts in an area roughly 12\deg$\times$ 6\deg (right ascension $\times$
declination) centered on the Shapley Supercluster (SSC). These correspond to
2627 different galaxies. Including other measurements reported in the
literature, the total number of galaxies with measured redshifts in a
19\deg$\times$ 16\deg area centered on the supercluster now reaches 5090. Of
these, 2949 lie in the redshift range 9,000 - 18,000 km s$^{-1}$, which we
tentatively identify with the SSC. This unprecedented sample allows a quite
detailed qualitative morphological study of the SSC. Based on the
three-dimensional distribution of galaxies and clusters of galaxies, we
identify several sub-condensations of the supercluster, as well as walls and
filaments connecting them. We also find another supercluster in the background,
at redshift $\sim$ 23,000 km s$^{-1}$.

</DOC>
<DOC>
<DOCNO> 122527 </DOCNO>
Trapped Disk Oscillations and Stable QPOs in Microquasars


  The observed quasi-periodic oscillations (QPOs) in low-mass X-ray binaries
have been suggested to be probably related to the characteristic oscillation
modes in the inner part of a relativistic accretion disk. In this paper we
study the trapped feature of these oscillation modes by considering the radial
perturbations and viscosity effects. We find that the trapped oscillations are
amplified significantly when the viscosity parameter increases and the trapped
size varies when the radial wavenumber and Mach number change. Our results
support that the stable hundred-hertz QPOs and their low fractional rms
amplitudes found in two Galactic microquasars may be explained by some trapped
non-damping oscillation modes in the inner part of accretion disks around
rotating black holes.

</DOC>
<DOC>
<DOCNO> 117510 </DOCNO>
Thermonuclear Runaways on Accreting White Dwarfs: Models of Classical


  The mechanism of classical novae explosions is explained, together with some
of their observational properties. The scarce but not null impact of novae in
the chemical evolution of the Milky Way is analyzed, as well as their relevance
for the radioactivity in the Galaxy. A special emphasis is given to the
predicted gamma-ray emission from novae and its relationship with the
thermonuclear model itself and its related nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 100067 </DOCNO>
Branching rules for modular fundamental representations of symplectic


  In this paper branching rules for the fundamental representations of the
symplectic groups in positive characteristic are found. The submodule structure
of the restrictions of the fundamental modules for the group $Sp_{2n}(K)$ to
the naturally embedded subgroup $Sp_{2n-2}(K)$ is determined. As a corollary,
inductive systems of fundamental representations for $Sp_{\infty}(K)$ are
classified. The submodule structure of the fundamental Weyl modules is refined.

</DOC>
<DOC>
<DOCNO> 119945 </DOCNO>
Study of the depletion effect in the cluster MS1008-1224


  We present a detailed study of the depletion effect (the radial manifestation
of the magnification bias) in the cluster MS1008-1224. Following our results
concerning the simulations of depletion curves (see Mayen and Soucail, 2000
(astro-ph/0003332) for a complete description of the code), we propose to
constrain the mass profile of the cluster and the main characteristics of its
potential (orientation and ellipticity). This application is based solely on
deep photometry of the field and does not require the measurement of the shape
parameters of the faint background galaxies.

</DOC>
<DOC>
<DOCNO> 151952 </DOCNO>
Four Quantum Conservation Laws for Black Hole Stationary Equilibrium


  The classical first law of thermodynamics for a Kerr-Newman black hole (KNBH)
is generalized to a law in quantum form on the event horizon. Then four quantum
conservation laws on the KNBH equilibrium radiation process are derived. The
Bekenstein-Hawking relation ${\cal{S}}={\cal{A}}/4$ is exactly established. It
can be inferred that the classical entropy of black hole arises from the
quantum entropy of field quanta or quasi-particles inside the hole.

</DOC>
<DOC>
<DOCNO> 13459 </DOCNO>
"Cold Melting" of Invar Alloys


  An anomalously strong volume magnetostriction in Invars may lead to a
situation when at low temperatures the dislocation free energy becomes negative
and a multiple generation of dislocations becomes possible. This generation
induces a first order phase transition from the FCC crystalline to an amorphous
state, and may be called "cold melting". The possibility of the cold melting in
Invars is connected with the fact that the exchange energy contribution into
the dislocation self energy in Invars is strongly enhanced, as compared to
conventional ferromagnetics, due to anomalously strong volume magnetostriction.
The possible candidate, where this effect can be observed, is a FePt disordered
Invar alloy in which the volume magnetostriction is especially large.

</DOC>
<DOC>
<DOCNO> 117453 </DOCNO>
Nature of eclipsing pulsars


  We present a model for pulsar radio eclipses in some binary systems, and test
this model for PSRs B1957+20 and J2051-0827. We suggest that in these binaries
the companion stars are degenerate dwarfs with strong surface magnetic fields.
The magnetospheres of these stars are permanently infused by the relativistic
particles of the pulsar wind. We argue that the radio waves emitted by the
pulsar split into the eigenmodes of the electron-positron plasma as they enter
the companion's magnetosphere and are then strongly damped due to cyclotron
resonance with the ambient plasma particles. Our model explains in a natural
way the anomalous duration and behavior of radio eclipses observed in such
systems. In particular, it provides stable, continuous, and frequency-dependent
eclipses, in agreement with the observations. We predict a significant
variation of linear polarization both at eclipse ingress and egress. In this
paper we also suggest several possible mechanisms of generation of the optical
and $X$-ray emission observed from these binary systems.

</DOC>
<DOC>
<DOCNO> 120483 </DOCNO>
A Note on TeV Cerenkov Events as Bose-Einstein Gamma Condensations


  The idea that the TeV air showers, thought to be produced by >10 TeV gamma
rays from Mrk 501, can be mimicked by coherent bunches of sub-TeV photons is
reexamined, focusing on fundamental considerations. In particular, it is shown
that the minimum spot size of the beam of pulsed TeV photons arriving at Earth
is on the order of a few kilometers, unless a lens with certain characteristics
is placed between the TeV laser and Earth. The viability of the laser
production mechanism proposed by Harwit et al. (2000) is also reassessed.

</DOC>
<DOC>
<DOCNO> 122667 </DOCNO>
Stars & Gas in the Galaxy Pair II Zw 70/71


  II Zw 71 (UGC 9562) was classified as a ``probable'' polar-ring galaxy in the
Polar-Ring Catalog, based upon its optical appearance. We present 21 cm and
optical observations of this galaxy and its companion, the blue star-forming
dwarf II Zw 70. Our 21 cm observations show that 5e8 solar masses of HI is
present in a polar ring orbiting II Zw 71, and show a spatially and
kinematically contiguous streamer with 2.5e8 solar masses of HI gas between the
two galaxies. This gaseous bridge, plus our observations of Halpha line
emission in the polar ring and in II Zw 70, are strong evidence for an ongoing
interaction between the two galaxies. However, the configuration of the
streamer suggests that the polar ring itself may well have predated the current
interaction, which then stimulated an outburst of star formation in the ring
gas.

</DOC>
<DOC>
<DOCNO> 84670 </DOCNO>
Primordial fluctuations of the metric in the warm inflation scenario


  I consider a semiclassical expansion of the scalar field in the warm
inflation scenario. I study the evolution for the fluctuations of the metric
around the Friedmann-Robertson-Walker one. The formalism predicts that, in the
power-law expansion universe, the fluctuations of the metric decreases with
time.

</DOC>
<DOC>
<DOCNO> 102105 </DOCNO>
Complex Lagrangian embeddings of moduli spaces of vector bundles


  By means of a Fourier-Mukai transform we embed moduli spaces of stable
bundles on an algebraic curve C as isotropic subvarieties of moduli spaces of
mu-stable bundles on the Jacobian variety J(C). When g(C)=2 this provides new
examples of special Lagrangian submanifolds.

</DOC>
<DOC>
<DOCNO> 7859 </DOCNO>
Ground and Metastable States in $\gamma$-Ce from Correlated Band Theory


  Multiple energy minima of the LDA+U energy functional are obtained for
$\gamma$-Ce when it is implemented in a full potential, rotationally invariant
scheme including spin-orbit coupling, and different starting local
configurations are chosen. The lowest energy solution leads to a fully spin
polarized 4f state and the lattice constant of $\gamma$-Ce. The higher energy
local minima (additional self-consistent solutions) are shown to be strongly
indicative of crystal electric field and multiplet excitations.

</DOC>
<DOC>
<DOCNO> 178890 </DOCNO>
Double-beta decay matrix elements for Ge-76


  Double-beta decay matrix elements (ME) for $^{76}Ge$ are calculated with
different quasi random phase approximation (QRPA)-based methods. First, the ME
for the two-neutrino mode are computed using two choices for the single
particle (s.p.) basis: i) $2-4\hbar\omega$ full shells and ii) $3-4\hbar\omega$
full shells. When calculated with the renormalized QRPA (RQRPA) and full-RQRPA
their values are rather dependent on the size of the single particle basis
used, while calculated with proton-neutron QRPA (pnQRPA) and second-QRPA
approaches such a dependence was found to be small. The Ikeda sum rule was well
fulfilled within pnQRPA for both choices of the s.p. basis and with a good
approximation within second-QRPA, while the RQRPA and full-RQRPA methods give
deviations up to 21%. Further, the ME for the neutrinoless mode are calculated
with the pnQRPA, RQRPA and full-RQRPA methods. They all give close results for
the calculation with the smaller basis (i), while for the larger basis (ii),
the results differ significantly either from one method to another or within
the same method. Finally, using the most recent experimental limit for the
$0\nu\beta\beta$ decay half-life of $^{76}Ge$ a critical discussion on the
upper limits for the neutrino mass parameter obtained with different
theoretical approaches is given.

</DOC>
<DOC>
<DOCNO> 8607 </DOCNO>
Effect of field tilting on the vortices in irradiated Bi-2212


  We report on transport measurements in a Bi-2212 single crystal with columnar
defects parallel to the c-axis. The tilt of the magnetic field away from the
direction of the tracks is studied for filling factors f=B_z/B_phi<1. Near the
Bose Glass transition temperature T_BG, the angular scaling laws are verified
and we find the field independent critical exponents nu'=1.1 and z'=5.30.
Finally, above H_perpC we evidence the signature of a smectic-A like vortex
phase. These experimental results provide support for the Bose Glass theory.

</DOC>
<DOC>
<DOCNO> 120699 </DOCNO>
B3 0003+387: AGN Marked Large-Scale Structure at z=1.47?


  We present evidence for a significant overdensity of red galaxies, as much as
a factor of 14 over comparable field samples, in the field of the z=1.47 radio
galaxy B3 0003+387. The colors and luminosities of the brightest red galaxies
are consistent with their being at z>0.8. The radio galaxy and one of the red
galaxies are separated by 5" and show some evidence of a possible interaction.
However, the red galaxies do not show any strong clustering around the radio
galaxy nor around any of the brighter red galaxies. The data suggest that we
are looking at a wall or sheet of galaxies, possibly associated with the radio
galaxy at z=1.47. Spectroscopic redshifts of these red galaxies will be
necessary to confirm this large-scale structure.

</DOC>
<DOC>
<DOCNO> 169683 </DOCNO>
Teleportation and Secret Sharing with Pure Entangled States


  We present two optimal methods of teleporting an unknown qubit using any pure
entangled state. We also discuss how such methods can also have succesful
application in quantum secret sharing with pure multipartite entangled states.

</DOC>
<DOC>
<DOCNO> 69637 </DOCNO>
Parton densities and structure functions beyond the next-to-leading


  We briefly discuss recent results on the evolution of unpolarized parton
densities and structure functions in massless perturbative QCD. Present partial
results on the next-to-next-to-leading order (NNLO) evolution kernels prove
sufficient for reliable calculations at not too small values of the Bjorken
variable, x > 10^-3. One order more can be taken into account at x >= 0.2.
Inclusion of these terms considerably reduces the main theoretical
uncertainties of determinations of alpha_s (to about 1% at the Z-mass) and the
parton densities from structure functions.

</DOC>
<DOC>
<DOCNO> 8027 </DOCNO>
Spinless fermions and charged stripes at the strong-coupling limit


  Spinless fermions on a lattice with nearest-neighbor repulsion serve as a toy
version Hubbard model, and have a symmetry-broken even/odd superlattice at
half-filling. At infinite repulsion, doped holes form charged stripes which are
antiphase walls (as noted by Mila in 1994). Exact-diagonalization data for
systems up to 36 sites around 1/4 filling, and also for one or two holes added
to a stripe of length up to 12, indicate stability of the stripe-array state
against phase separation. In the {\it boson} version of the model, the same
behavior can be stabilized by addition of a four-fermi term.

</DOC>
<DOC>
<DOCNO> 10929 </DOCNO>
Annihilation-diffusion processes: an exactly solvable model


  A family of diffusion-annihilation processes is introduced, which is exactly
solvable. This family contains parameters that control the diffusion- and
annihilation- rates. The solution is based on the Bethe ansatz and using
special boundary conditions to represent the reaction. The processes are
investigated, both on the lattice and on the continuum. Special cases of this
family of processes are the simple exclusion process and the drop-push model.

</DOC>
<DOC>
<DOCNO> 10038 </DOCNO>
Interband absorption and luminescence in small quantum dots under strong


  Interband absorption and luminescence of quasi-two-dimensional, circularly
symmetric, N_e electron quantum dots are studied at high magnetic fields,
8<B<60 T, and low temperatures, T<<2 K. In the N_e=0 and 1 dots, the initial
and final states of such processes are fixed, and thus the dependence on B of
peak intensities is monotonic. For larger systems, ground state rearrangements
with varying magnetic field lead to substantial modifications of the absorption
and luminescence spectra. Collective effects are seen in the N_e=2 and 3 dots
at "filling factors" 1/2, 1/3 and 1/5.

</DOC>
<DOC>
<DOCNO> 170813 </DOCNO>
High-Precision Value for the Quartic Anharmonic Oscillator Ground State


  We will describe how a new, quite simple, but highly effective algorithm,
together with the asymptotically fast FFT-based high-precision number
multiplication of Mathematica 4 can calculate the ground state of the x^4
anharmonic oscillator to the new record of more than 1000 digits.

</DOC>
<DOC>
<DOCNO> 121915 </DOCNO>
Constraining the cosmological parameters from gravitational lenses with


  The knowledge of the redshift of multiple images in cluster-lenses allows to
determine precisely the total projected mass within the Einstein radius. The
observation of various multiple images in a same cluster is opening new
possibilities to constrain the curvature of the universe. Indeed, although the
influence of $\Omega_m$ and $\Omega_\lambda$ on the images formation is of the
second order, observations of many multiple images at different redshifts
formed by a regular cluster-lens should allow to constrain very accurately the
mass distribution of the cluster and to start to be sensitive to the
cosmological parameters entering the diameter angular distances. We present,
analytical expressions and numerical simulations that allow us to compute the
expected error bars on the cosmological parameters provided an HST/WFPC2
resolution image and spectroscopic redshifts for the multiple images. Numerical
tests on simulated data confirm the rather small uncertainties we could obtain
this way for the two popular cosmological world models: $\Omega_m=0.3{\pm
0.24}$, $\Omega_\lambda=0.7{\pm 0.5}$ or $\Omega_m=1.{\pm 0.33}$,
$\Omega_\lambda=0.{\pm 1.2}$. Our method can be applied from now on, on real
clusters.

</DOC>
<DOC>
<DOCNO> 118909 </DOCNO>
Discovery and Photometric Observation of the Optical Counterpart in a


  We discovered the optical counterpart about 13 mag of a soft X-ray transient,
XTE J1118+480 on 2000 March 30. We perform astrometry and provide the accurate
position as R.A. = 11h18m10s.85, Decl. = +48o02'12".9. The outbursting object
is identified with a 18.8 mag star in USNO catalog. Our pre-discovery data
shows another outburst during 2000 January, again coinciding with an outburst
detected in X-rays. Through the CCD time-series photometry, we found the
presence of a periodic variation with the amplitude of 0.055 mag and the period
of 0.17078(0.00004)d which we consider as promising candidate of orbital
period. Because of the high galactic latitude and faint quiescence magnitude of
18.8, XTE J1118+480 is the possible first firmly identified black hole
candidate (BHC) X-ray transient in the galactic halo.

</DOC>
<DOC>
<DOCNO> 100395 </DOCNO>
Tangent scrolls in prime Fano threefolds


  In this paper we prove that any smooth prime Fano threefold, different from
the Mukai-Umemura threefold, contains a 1-dimensional family of intersecting
lines. Combined with a result of the second author (see J. Algebr. Geom. 8:2
(1999), 221-244) this implies that any morphism from a smooth Fano threefold of
index 2 to a smooth Fano threefold of index 1 must be constant, which gives an
answer in dimension 3 to a question stated by Peternell.

</DOC>
<DOC>
<DOCNO> 118398 </DOCNO>
Primordial black holes and gravitational memory


  We discuss the various ways in which primordial black holes may have formed
in the early Universe and how the effects of such black holes can be used to
place constraints on cosmological models. We show that such constraints may be
severely modified if the value of the gravitational "constant" G varies with
cosmological epoch, a possibility which arises in many scenarios for the early
Universe. The nature of the modification depends upon whether the value of G
near a black hole maintains the value it had at its formation epoch
(corresponding to gravitational memory) or whether it tracks the background
cosmological value. This is still uncertain but we discuss various approaches
which might help to resolve the issue.

</DOC>
<DOC>
<DOCNO> 100850 </DOCNO>
Tangency quantum cohomology


  Let X be a smooth projective variety. Using modified psi classes on the stack
of genus zero stable maps to X, a new associative quantum product is
constructed on the cohomology space of X. When X is a homogeneous variety, this
structure encodes the characteristic numbers of rational curves in X, and
specialises to the usual quantum product upon resetting the parameters
corresponding to the modified psi classes. For X = P^2, the product is
equivalent to that of the contact cohomology of Ernstrom-Kennedy.

</DOC>
<DOC>
<DOCNO> 169922 </DOCNO>
Probability in Orthodox Quantum Mechanics: Probability as a Postulate


  The role of probability in quantum mechanics is reviewed, with a discussion
of the ``orthodox'' versus the statistical interpretive frameworks, and of a
number of related issues. After a brief summary of sources of unease with
quantum mechanics, a survey is given of attempts either to give a new
interpretive framework assuming quantum mechanics is exact, or to modify
quantum mechanics assuming it is a very accurate approximation to a more
fundamental theory. This survey focuses particularly on the issues of whether
probabilities in quantum mechanics are postulated or emergent.

</DOC>
<DOC>
<DOCNO> 69676 </DOCNO>
Introduction to Monte Carlo methods


  These lectures given to graduate students in high energy physics, provide an
introduction to Monte Carlo methods. After an overview of classical numerical
quadrature rules, Monte Carlo integration together with variance-reducing
techniques is introduced. A short description on the generation of
pseudo-random numbers and quasi-random numbers is given. Finally, methods to
generate samples according to a specified distribution are discussed. Among
others, we outline the Metropolis algorithm and give an overview of existing
algorithms for the generation of the phase space of final state particles in
high energy collisions.

</DOC>
<DOC>
<DOCNO> 10237 </DOCNO>
The orbital moment in NiO


  The orbital and spin moment of the Ni2+ ion in NiO has been calculated within
the quasi-atomic approach. The orbital moment of 0.54 mB amounts at 0 K, in the
magnetically-ordered state, to more than 20% of the total moment (2.53 mB). For
this outcome, being in nice agreement with the recent experimental finding
taking into account the spin-orbit coupling is indispensable.

</DOC>
<DOC>
<DOCNO> 8992 </DOCNO>
Breakdown of universality in multi-cut matrix models


  We solve the puzzle of the disagreement between orthogonal polynomials
methods and mean field calculations for random NxN matrices with a disconnected
eigenvalue support. We show that the difference does not stem from a Z2
symmetry breaking, but from the discreteness of the number of eigenvalues. This
leads to additional terms (quasiperiodic in N) which must be added to the naive
mean field expressions. Our result invalidates the existence of a smooth
topological large N expansion and some postulated universality properties of
correlators. We derive the large N expansion of the free energy for the general
2-cut case. From it we rederive by a direct and easy mean-field-like method the
2-point correlators and the asymptotic orthogonal polynomials. We extend our
results to any number of cuts and to non-real potentials.

</DOC>
<DOC>
<DOCNO> 72259 </DOCNO>
Light sigma-Meson Production in Excited Upsilon Decay Processes II:


  The results of analyses obtained in Part I are examined from the viewpoint of
chiral symmetry. The mass spectra of pi pi system are widely believed to be
suppressed generally near the threshold, because of the derivative coupling
property of Nambu-Goldstone pi meson. However, this suppression does not hold
in the processes with large energy release, and the steep increase from the pi
pi threshold observed in the transition Upsilon (3S-->1S) is shown to be
consistent with general constraints from chiral symmetry.

</DOC>
<DOC>
<DOCNO> 99431 </DOCNO>
Une formule de type Baker-Campbell-Hausdorff pour les groupoides de Lie


  For a Lie groupoid G we prove an analogous of the Baker-Campbell-Hausdorff
formula and we calculate the structure functions of the Lie algebroid
associated to G.

</DOC>
<DOC>
<DOCNO> 117802 </DOCNO>
Spectral Evolution of the Peculiar Ic Supernova 1998bw


  SN 1998bw holds the record for the most energetic Type Ic explosion, one of
the brightest radio supenovae and probably the first supernova associated with
a gamma-ray burst. In this paper we present spectral observations of SN 1998bw
observed in a cooperative monitoring campaign using the AAT, UKST and the SSO
2.3-m telescope. We investigate the evolution of the spectrum between 7 and 94
days after V_band maximum in comparison to well-studied examples of Type Ic SNe
in order to quantify the unusual properties of this supernova event. Though the
early spectra differ greatly from the observations of classical Ic SNe, we find
that the evolution from the photospheric to the nebular phases is slow but
otherwise typical. The spectra differ predominantly in the extensive line
blending and blanketing which has been attributed to the high velocity of the
ejecta. We find that by day 19, the absorption line minima blueshifts are 10% -
50% higher than other SNe and on day 94 emission lines are 45% broader, as
expected if the progenitor had a massive envelope. However, it is difficult to
explain the extent of line blanketing entirely by line broadening, and we argue
that additional contribution from other species is present, indicating unusual
relative abundances or physical conditions in the envelope.

</DOC>
<DOC>
<DOCNO> 123328 </DOCNO>
Innermost stable circular orbits around rotating compact quark stars and


  It has been suggested that observations of quasi periodic oscillations (QPOs)
in the X-ray fluxes from low mass X-ray binaries can be used to constrain the
mass of the compact object and the equation of state of its matter. A specific
suggestion that the kHz QPO frequency saturates at the maximum orbital
frequency has been widely considered. We examine rotating compact stars
described by a new model of strange quark matter (Dey et al. 1998). We
calculate the maximum orbital frequencies for both normal and supramassive
strange stars described by the Dey model, and present these frequencies for
sequences of equilibrium models with constant baryon mass. The maximum orbital
frequencies for these compact objects are always higher than the kHz QPO
frequencies observed to date.

</DOC>
<DOC>
<DOCNO> 12273 </DOCNO>
Nanometer-sized Regions of Charge Ordering and Charge Melting in


  Electron microdiffraction study of phase transition in La2/3Ca1/3MnO3
revealed temperature dependent (h+1/2,0,l) diffraction spots. Their intensity
peaks at Tc. Quantitative electron diffraction intensity analysis shows that
they come from nanometer-sized domains with modulated transverse atomic
displacements in the orthorhombic a-c plane, which has two types of Mn ions and
thus charge ordering. The average domain is ~3.6 nm in diameter and ~1.5 nm in
height (along the b-axis). The number of domains increases and then decreases,
as the sample is cooled through Tc.

</DOC>
<DOC>
<DOCNO> 101380 </DOCNO>
Quantum invariants of 3-manifolds and Poincar\'{e} conjecture


  In this paper we propose a new quantum gauge model. From this gauge model we
derive quantum invariants of 3-manifolds. We show that these invariants
classify closed (orientable and connected) 3-manifolds.
 From this classification we then prove the Poincar\'{e} conjecture.

</DOC>
<DOC>
<DOCNO> 84452 </DOCNO>
Boundaries of Zero Scalar Curvature in the AdS/CFT Correspondence


  In hep-th/9910245, Witten and Yau consider the AdS/CFT correspondence in the
context of a Riemannian Einstein manifold $M^{n+1}$ of negative Ricci curvature
which admits a conformal compactification with conformal boundary $N^n$. They
prove that if the conformal class of the boundary contains a metric of positive
scalar curvature, then $M$ and $N$ have several desirable properties: (1) $N$
is connected, (2) the $n$th homology of the compactified $M$ vanishes, and (3)
the fundamental group of $M$ is "bounded by" that of $N$. Here it is shown that
all of these results extend to the case where the conformal class of the
boundary contains a metric of nonnegative scalar curvature. (The case of zero
scalar curvature is of interest as it is borderline for the stability of the
theory.) The proof method used here is different from, and in some sense dual
to, that used by Witten and Yau. While their method involves minimizing the
co-dimension one brane action on $M$, and requires the machinery of geometric
measure theory, the main arguments presented here use only geodesic geometry.

</DOC>
<DOC>
<DOCNO> 101456 </DOCNO>
Classifying characteristic functions giving Weyl-Heisenberg frames


  We examine the question of which characteristic functions yield
Weyl-Heisenberg frames for various values of the parameters. We also give
numerous applications of frames of characteristic functions to the general case
(g,a,b).

</DOC>
<DOC>
<DOCNO> 13592 </DOCNO>
Indirect hyperfine interaction between nuclear-spin qubits in mesoscopic


  Theoretical study of the indirect coupling of nuclear spins (qubits) embedded
into a mesoscopic ring and in a finite length quantum wire in a magnetic field
is presented. It is found that the hyperfine interaction, via the conduction
electrons, between nuclear spins exhibits sharp maxima as function of the
magnetic field and nuclear spin positions. This phenomenon can be used for
manipulation of qubits with atomic precision. Experimental feasibility and
implications for quantum logics devices is discussed.

</DOC>
<DOC>
<DOCNO> 84261 </DOCNO>
A new singularity theorem in relativistic cosmology


  It is shown that if the timelike eigenvector of the Ricci tensor be
hypersurface orthogonal so that the space time allows a foliation into space
sections then the space average of each of the scalar that appear in the
Raychaudhuri equation vanishes provided the strong energy condition holds good.
This result is presented in the form of a singularity theorem.

</DOC>
<DOC>
<DOCNO> 72134 </DOCNO>
Resonance Propagation and Threshold Singularities


  We consider the problem of propagation of an unstable particle in the
framework of Quantum Field Theory. Using unitarity, we show that a real
renormalization constant free of threshold singularities naturally arises.

</DOC>
<DOC>
<DOCNO> 102204 </DOCNO>
Ricci flow on Kaehler-Einstein surfaces


  In this paper, we construct a set of new functionals of Ricci curvature on
any Kaehler manifolds which are invariant under holomorphic transfermations in
Kaehler Einstein manifolds and essentially decreasing under the Kaehler Ricci
flow. Moreover, if the initial metric has non-negative bisectional curvature,
using Tian's inequality, we can prove that each of the functionals has uniform
lower bound along the flow which gives a set of integral estimates on
curvature. Using this set of integral estimates, we are able to show the
following theorem: Let M be a Kaehler-Einstein surface with positive scalar
curvature. If the initial metric has nonnegative sectional curvature and
positive somewhere, then the Kaehler-Ricci flow converges exponentially fast to
a Kaehler-Einstein metric with constant bisectional curvature.

</DOC>
<DOC>
<DOCNO> 117240 </DOCNO>
Electromagnetic oscillations in periodic mediums outside the passbands


  It was usually assumed that the resonator based on a waveguide has the eigen
oscillations that are formed by interference of two waves which propagate in
different directions and have equal amplitudes. These patterns are usually
called standing waves. We have shown that the eigen oscillations of a resonator
which is filled by a layered dielectric can be base on the evanescent
(non-propagating) waves. In some cases we need only one eigen wave to compose
the eigen oscillation of a closed cavity.

</DOC>
<DOC>
<DOCNO> 8043 </DOCNO>
Phase Diagram of a Classical Fluid in a Quenched Random Potential


  We consider the phase diagram of a classical fluid in the presence of a
random pinning potential of arbitrary strength. Introducing replicas for
averaging over the quenched disorder, we use the hypernetted chain
approximation to calculate the correlations in the replicated liquid. The
freezing transition of the liquid into a nearly crystalline state is studied
using a density functional approach, and the liquid-to-glass transition is
studied using a phenomenological replica symmetry breaking approach introduced
by Mezard and Parisi. The first-order liquid-to-crystal transition is found to
change to a continuous liquid-to-glass transition as the strength of the
disorder is increased above a threshold value.

</DOC>
<DOC>
<DOCNO> 119116 </DOCNO>
XID: Cross-Association of ROSAT/Bright Source Catalog X-ray Sources with


  We quantitatively cross-associate the 18811 ROSAT Bright Source Catalog
(RASS/BSC) X-ray sources with optical sources in the USNO-A2 catalog,
calculating the the probability of unique association (Pid) between each
candidate within 75 arcsec of the X-ray source position, on the basis of
optical magnitude and proximity. We present catalogs of RASS/BSC sources for
which the probability of association is >98%, >90%, and >50%, which contain
2705, 5492, and 11301 unique USNO-A2 optical counterparts respectively down to
the stated level of significance. We include in this catalog a list of objects
in the SIMBAD database within 10 arcsec of the USNO position, as an aid to
identification and source classification. The catalog is more useful than
previous catalogs which either rely on plausibility arguments for association,
or do not aid in selecting a counterpart between multiple off-band sources in
the field. We find that a fraction ~65.8% of RASS/BSC sources have an
identifiable optical counterpart, down to the magnitude limit of the USNO
catalog which could be identified by their spatial proximity and high optical
brightness.

</DOC>
<DOC>
<DOCNO> 118986 </DOCNO>
Sub-Saturn Planet Candidates to HD 16141 and HD 46375


  Precision Doppler measurements from the Keck/HIRES spectrometer reveal
periodic Keplerian velocity variations in the stars HD 16141 and HD 46375. HD
16141 (G5 IV) has a period of 75.8 d and a velocity amplitude of 11 m/s,
yielding a companion having Msini = 0.22 Mjup and a semimajor axis, a = 0.35
AU. HD 46375 (K1 IV/V) has a period of 3.024 d and a velocity amplitude of 35
m/s, yielding a companion with Msini=0.25 Mjup, a semimajor axis of a = 0.041
AU, and an eccentricity of 0.04 (consistent with zero). These companions
contribute to the rising planet mass function toward lower masses.

</DOC>
<DOC>
<DOCNO> 118504 </DOCNO>
Type Ia Supernovae: Progenitors and Evolution with Redshift


  Relatively uniform light curves and spectral evolution of Type Ia supernovae
(SNe Ia) have led to the use of SNe Ia as a ``standard candle'' to determine
cosmological parameters. Whether a statistically significant value of the
cosmological constant can be obtained depends on whether the peak luminosities
of SNe Ia are sufficiently free from the effects of cosmic and galactic
evolutions.
  Here we first review the single degenerate scenario for the Chandrasekhar
mass white dwarf (WD) models of SNe Ia. We identify the progenitor's evolution
and population with two channels: (1) the WD+RG (red-giant) and (2) the WD+MS
(near main-sequence He-rich star) channels. In these channels, the strong wind
from accreting WDs plays a key role, which yields important age and metallicity
effects on the evolution.
  We then address the questions whether the nature of SNe Ia depends
systematically on environmental properties such as metallicity and age of the
progenitor system and whether significant evolutionary effects exist. We
suggest that the variation of the carbon mass fraction $X$(C) in the C+O WD (or
the variation of the initial WD mass) causes the diversity of the brightness of
SNe Ia. This model can explain the observed dependences of SNe Ia brightness on
the galaxy types and the distance from the galactic center.
  Finally, applying the metallicity effect on the evolution of SN Ia
progenitors, we make a prediction of the cosmic supernova rate history as a
composite of the supernova rates in different types of galaxies.

</DOC>
<DOC>
<DOCNO> 84799 </DOCNO>
Numerical evolution of Brill waves


  We report a numerical evolution of axisymmetric Brill waves. The numerical
algorithm has new features, including (i) a method for keeping the metric
regular on the axis and (ii) the use of coordinates that bring spatial infinity
to the edge of the computational grid. The dependence of the evolved metric on
both the amplitude and shape of the initial data is found.

</DOC>
<DOC>
<DOCNO> 67874 </DOCNO>
A Comparison between Relativistic and Semi-Relativistic Treatment in the


  In the diquark-quark model of the nucleon including scalar and axialvector
diquarks we compare solutions of the ladder Bethe-Salpeter equation in the
instantaneous Salpeter approximation and in the fully covariant (i.e.
four-dimensional) treatment. We obtain that the binding energy is severly
underestimated in the Salpeter approximation. For the electromagnetic form
factors of the nucleon we find that in both approaches the overall shapes of
the respective form factors are reasonably similar up to $Q^2 \approx 0.4$
GeV^2. However, the magnetic moments differ substantially as well as results
for the pion-nucleon and the axial coupling of the nucleon.

</DOC>
<DOC>
<DOCNO> 102394 </DOCNO>
Minimal entropy and collapsing with curvature bounded from below


  We show that if a closed manifold M admits an F-structure (possibly of rank
0) then its minimal entropy vanishes. In particular, this is the case if M
admits a non-trivial circle action. As a corollary we obtain that the
simplicial volume of a colsed manifold admitting an F-structure is zero. We
also show that if M admits an F-structure then it collapses with curvature
bounded from below. This is turn implies that M collapses with bounded scalar
curvature or, equivalently, its Yamabe invariant is non-negative. We show that
F-structures of rank zero appear rather frequently:every compact complex
elliptic surface admits one as well as any simply connected 5-manifold. We use
these results to study the minimal entropy problem. We show the following two
theorems: suppose M is obtained by taking connected sums of copies of CP^2
(with any orintation), S^2 \times S^2 and the K3 surface. Then M has zero
minimal entropy. Moreover, M admits a metric with zero topological entropy if
and only if M is diffeomorphic to S^4, CP^2, S^2 \times S^2, CP^2#CP^2 or
CP^2#(-CP^2). Finally, suppose that M is a closed simply connected 5-manifold.
Than M has zero minimal entropy. Moreover, M admits a metric with zero
topological entropy if and only if M is diffeomorphic to S^5, S^3 \times S^2,
the non-trivial S^3-bundle over S^2 or the Wu manifold SU(3)/SO(3).

</DOC>
<DOC>
<DOCNO> 84618 </DOCNO>
Covariant two point function for minimally coupled scalar field in de


  In a recent paper [1], it has been shown that negative norm states are
indispensable for a fully covariant quantization of the minimally coupled
scalar field in de Sitter space. Their presence, while leaving unchanged the
physical content of the theory, offers an automatic and covariant
renormalization of the vacuum energy divergence. This paper is a completion of
our previous work. An explicit construction of the covariant two-point function
of the ``massless'' minimally coupled scalar field in de Sitter space is given,
which is free of any infrared divergence. The associated Schwinger commutator
function and retarded Green's function are calculated in a fully gauge
invariant way, which also means coordinate independent.

</DOC>
<DOC>
<DOCNO> 116270 </DOCNO>
Beam Coupling Impedances of Small Discontinuities


  A general derivation of the beam coupling impedances produced by small
discontinuities on the wall of the vacuum chamber of an accelerator is
reviewed. A collection of analytical formulas for the impedances of small
obstacles is presented.

</DOC>
<DOC>
<DOCNO> 99854 </DOCNO>
Partitioning Sparse Graphs using the Second Eigenvector of their Graph


  Partitioning a graph into three pieces, with two of them large and connected,
and the third a small ``separator'' set, is useful for improving the
performance of a number of combinatorial algorithms. This is done using the
second eigenvector of a matrix defined solely in terms of the incidence matrix,
called the graph Laplacian. For sparse graphs, the eigenvector can be
efficiently computed using the Lanczos algorithm. This graph partitioning
algorithm is extended to provide a complete hierarchical subdivision of the
graph. The method has been implemented and numerical results obtained both for
simple test problems and for several grid graphs.

</DOC>
<DOC>
<DOCNO> 12768 </DOCNO>
Geometric frustration in the mixed layer pnictide oxides


  We present results from a Monte Carlo investigation of a simple bilayer model
with geometrically frustrated interactions similar to those found in the mixed
layer pnictide oxides $(Sr_{2}Mn_{3}Pn_{2}O_{2}, Pn=As,Sb).$ Our model is
composed of two inequivalent square lattices with nearest neighbor intra- and
interlayer interactions. We find a ground state composed of two independent
N\'{e}el ordered layers when the interlayer exchange is an order of magnitude
weaker than the intralayer exchange, as suggested by experiment. We observe
this result independent of the number of layers in our model. We find evidence
for local orthogonal order between the layers, but it occurs in regions of
parameter space that are not experimentally realized. We conclude that
frustration caused by nearest neighbor interactions in the mixed layer pnictide
oxides is not sufficient to explain the long--range orthogonal order that is
observed experimentally, and that it is likely that other terms (e.g., local
anisotropies) in the Hamiltonian are required to explain the magnetic behavior.

</DOC>
<DOC>
<DOCNO> 68531 </DOCNO>
Brane Cosmologies without Orbifolds


  We study the dynamics of branes in configurations where 1) the brane is the
edge of a single anti-de Sitter (AdS) space and 2) the brane is the surface of
a vacuum bubble expanding into a Schwarzschild or AdS-Schwarzschild bulk. In
both cases we find solutions that resemble the standard Robertson-Walker
cosmologies although in the latter, the evolution can be controlled by a mass
parameter in the bulk metric. We also include a term in the brane action for
the scalar curvature. This term adds a contribution to the low energy theory of
gravity which does not need to affect the cosmology but which is necessary for
the surface of the vacuum bubble to recover four dimensional gravity.

</DOC>
<DOC>
<DOCNO> 10344 </DOCNO>
Nanometer Scale Mapping of the Density of States in an Inhomogeneous


  Using high speed scanning tunneling spectroscopy, we perform a full mapping
of the quasiparticle density of states (DOS) in single crystals of
BiPbSrCaCuO(2212). The measurements carried out at 5 K showed a complex spatial
pattern of important variations of the local DOS on the nanometer scale.
Superconducting areas are co-existing with regions of a smooth and larger
gap-like DOS structure. The superconducting regions are found to have a minimum
size of about 3 nm. The role of Pb-introduced substitutional disorder in the
observed spatial variations of the local DOS is discussed.

</DOC>
<DOC>
<DOCNO> 72040 </DOCNO>
Triplet-doublet Splitting, Proton Stability and Extra Dimension


  We propose a new possibility to reconcile the coupling unification scenario
with the triplet-doublet mass splitting based on a 5-dimensional supersymmetric
model with SU(5) gauge symmetry. It is shown that the minimal supersymmetric
standard model is derived on a 4-dimensional wall through compactification on
$S^1/(Z_2 \times Z_2')$.

</DOC>
<DOC>
<DOCNO> 152307 </DOCNO>
Covariant Formulation of Field Theories associated with p-Branes


  We discuss the covariant formulation of local field theories described by the
Companion Lagrangian associated with p-branes. The covariantisation is shown to
be useful for clarifying the geometrical meaning of the field equations and
also their relation to the Hamilton-Jacobi formulation of the standard
Dirac-Born-Infeld theory.

</DOC>
<DOC>
<DOCNO> 69589 </DOCNO>
Universal quark-lepton mixing and determination of neutrino masses


  If three right-handed neutrinos are added to the Standard Model, then, for
the three known generations, there are six quarks and six leptons. It is then
natural to assume that the symmetry considerations that have been applied to
the quark matrices are also valid for the lepton mass matrices. Under this
assumption, the solar and atmospheric neutrino data can be used to determine
the individual neutrino masses. Three minima have been found, using the chi^2
fit, and, from these minima, it is determined that the mass of the lightest
neutrino is 1.3\times10^-3 eV, that of the next heavier neutrino is
1.3\times10^-2 eV, while the mass of the heaviest neutrino is 3.4\times10^-2,
5.8\times10^-2 or 9.4\times10^-2 eV.

</DOC>
<DOC>
<DOCNO> 100361 </DOCNO>
Period map for non-compact holomorphically symplectic manifolds


  We study the deformations of a holomorphic symplectic manifold $M$, not
necessarily compact, over a formal ring. We show (under some additional, but
mild, assumptions on $M$) that the coarse deformation space exists and is
smooth, finite-dimensional and naturally embedded into $H^2(M)$. For a
holomorphic symplectic manifold $M$ which satisfies $H^1(M,{\cal O}_M) =
H^2(M,{\cal O}_M)=0$, the coarse moduli of formal deformations is isomorphic to
$\Spec\C[[t_1, ..., t_n]]$, where $t_1$, ... $t_n$ are coordinates in $H^2(M)$.
  This revised version contains one minor improvement: exposition in Subsection
5.1 has been made more detailed and rigourous.

</DOC>
<DOC>
<DOCNO> 102585 </DOCNO>
Generalized uncertainty relations and coherent and squeezed states


  Characteristic uncertainty relations and their related squeezed states are
briefly reviewed and compared in accordance with the generalizations of three
equivalent definitions of the canonical coherent states. The standard SU(1,1)
coherent states are shown to be the unique states that minimize the
Schroedinger uncertainty relation for every pair of the three generators and
the Robertson relation for the three generators. The characteristic uncertainty
inequalities are naturally extended to the case of several states. It is shown
that these inequalities can be written in the equivalent complementary form.

</DOC>
<DOC>
<DOCNO> 14150 </DOCNO>
Chaotic Dynamics in Shear-thickening Surfactant Solutions


  We report the observation of dynamical behaviour in dilute, aqueous solutions
of a surfactant CTAT (cetyl trimethylammonium p-toluenesulphonate), below the
overlap concentration c$^{\star}$. At these concentrations, CTAT forms
cylindrical micelles and shows a pronounced shear thickening transition above a
concentration-dependent critical shear rate $\dot\gamma_{c}$. An analysis of
the time-series of the stress relaxations at controlled shear rates in the
shear-thickening regime shows the existence of correlation dimensions greater
than two and positive Lyapunov exponents. This indicates the existence of
deterministic chaos in the dynamics of stress relaxation at these
concentrations and shear rates. The observed chaotic behaviour may be
attributed to the stick-slip between the shear - induced structure (SIS) formed
in the sheared surfactant solution and the coexisting dilute phase. At still
higher shear rates, when the SIS spans the Couette, there is a transition to
higher-dimensional dynamics arising out of the breakage and recombination of
the SIS.

</DOC>
<DOC>
<DOCNO> 71393 </DOCNO>
Breit interaction correction to the hyperfine constant of an external


  Correction to the hyperfine constant $A$ of an external s-electron in
many-electron atom caused by the Breit interaction is calculated analytically:
$\delta A/A =0.68 Z\alpha^2$. Physical mechanism for this correction is
polarization of the internal electronic shells (mainly $1s^2$ shell) by the
magnetic field of the external electron. This mechanism is similar to the
polarization of vacuum considered by Karplus and Klein long time ago. The
similarity is the reason why in both cases (Dirac sea polarization and internal
atomic shells polarization) the corrections have the same dependence on the
nuclear charge and fine structure constant.
  In conclusion we also discuss $Z\alpha^2$ corrections to the parity violation
effects in atoms.

</DOC>
<DOC>
<DOCNO> 170334 </DOCNO>
Remote information concentration using a bound entangled state


  Remote information concentration, the reverse process of quantum telecloning,
is presented. In this scheme, quantum information originally from a single
qubit, but now distributed into three spatially separated qubits, is remotely
concentrated back to a single qubit via an initially shared entangled state
without performing any global operations. This entangled state is an unlockable
bound entangled state and we analyze its properties.

</DOC>
<DOC>
<DOCNO> 40185 </DOCNO>
High Power Testing Results of the X-Band Mixed-Mode RF Windows for


  In this paper, we summarize the high power testing results of the X-band
mixed-mode RF windows at KEK and SLAC for linear colliders. The main feature of
these windows is that the combination of modes on the surface of the ceramic
significantly decreases the electric and magnetic fields in the junction
between the ceramic and the metal. So far two types of high power windows (with
the diameter of 53 mm and 64 mm) have been fabricated. A high power model of
the smaller type window was fabricated and tested in a resonant ring at KEK. A
maximum circulating power of 81 MW with 300 ns duration or 66 MW with 700 ns
duration was achieved. Light emission was observed for a power level of over 10
MW. Later, both windows were shipped to SLAC for even higher power testing
using combined power from two klystrons. The first window (53 mm diameter)
achieved a transmitted power of 80 MW with 1.5 microsec duration at 30 Hz
repetition. It was not destroyed during the testing. The testing of the second
window was carried out next to the small type and achieved 62 MW with 1.5
maicrosec duration with 10 Hz repetition. The final results of both windows are
presented in this report.

</DOC>
<DOC>
<DOCNO> 40205 </DOCNO>
Search for B^+ --> K^+l^+l^- and B^0 --> K^(*0)l^+l^-


  Using a sample of 3.7 x 10^{6} Y(4S) --> B-anti-B events collected with the
BABAR detector at the PEP-II storage ring, we search for the electroweak
penguin decays B^+ --> K^+e^+e^-, B^+ --> K^+mu^+mu^-, B^0 --> K^{*0)e^+e^-,
and B^0 --> K^{*0)mu^+mu^-. We observe no significant signals for these modes
and set preliminary 90% C.L. upper limits of B(B^+ --> K^+e^+e^-) < 12.5 x
10^{-6}, B(B^+ --> K^+mu^+mu^-) < 8.3 x 10^{-6}, B(B^0 --> K^{*0)e^+e^-) < 24.1
x 10^{-6}, B(B^0 --> K^{*0)mu^+mu^-) < 24.5 x 10^{-6}.

</DOC>
<DOC>
<DOCNO> 116610 </DOCNO>
Superheated drop neutron spectrometer


  Superheated drops are known to detect neutrons through the nucleation caused
by the recoil nuclei produced by the interactions of neutrons with the atoms
constituting the superheated liquid molecule. A novel method of finding the
neutron energy from the temperature dependence response of SDD has been
developed. From the equivalence between the dependence of threshold energy for
nucleation on temperature of SDD and the dependence of dE/dx of the recoil ions
with the energy of the neutron, a new method of finding the neutron energy
spectrum of a polychromatic as well as monochromatic neutron source has been
developed.

</DOC>
<DOC>
<DOCNO> 169882 </DOCNO>
On the compatibility between the Markov property and the quantum jump


  A brief analysis of the compatibility between the quantum jump and the Markov
property for quantum systems described by a stochastic evolution scheme is
presented.

</DOC>
<DOC>
<DOCNO> 119596 </DOCNO>
E&F White conference on Radio Frequency Interference Mitigation


  The conference brought together expertise on a range of interference
mitigation techniques from CSIRO, Australian and international industry and
universities. Key goals were to: enhance the understanding of techniques and
their inter-relationship, increase awareness of advanced technologies such as
software radios and photonics, and foster a cooperative approach to the
development of interference mitigation techniques. The foremost application in
mind was the square kilometre array (SKA) and the need to find ways to develop
an hierarchical scheme for removing unwanted signals from astronomical data.
This paper gives an overview of the topics discussed at the conference and
summarises some of the key ideas and results that were presented.
  Many of the interference challenges we face can be overcome with technical
solutions. There will always be a place for regulatory and legal approaches to
spectrum management, but too much reliance has been placed on these in the
past. The strategy of avoidance has worked well in the past and will continue
to be useful in the future, but is now limited by the growth of space based
communications systems, which are visible everywhere on Earth. There is no
technical solution which is likely to provide a silver bullet. Rather a
hierarchical approach will be required, combining a range of techniques. We
have just begun exploring technical solutions and their toxicity to
astronomical data. We need to continue on this path, determining which
techniques are best and how they interact in order to develop a flexible and
powerful system for interference suppression.

</DOC>
<DOC>
<DOCNO> 72079 </DOCNO>
Analysis of the atmospheric neutrino data in terms of 3-neutrino


  A global analysis of atmospheric and reactor neutrino data is presented in
terms of three-neutrino oscillations. We consider in our analysis both
contained events and upward-going neutrino-induced muon events, including the
previous data samples of Frejus, IMB, Nusex, and Kamioka experiments as well as
the full 71 kton-yr (1144 days) Super-Kamiokande data set, the recent 5.1
kton-yr contained events of Soudan-2 and the results on upgoing muons from the
MACRO detector. After presenting the results for the analysis of atmospheric
data alone, we add to our data sample the reactor bound of the CHOOZ
experiment, showing and important complementarity between the atmospheric and
reactor limits which results in a stronger constraint on the allowed value of
theta_13.

</DOC>
<DOC>
<DOCNO> 69420 </DOCNO>
Two-loop Radiative Neutrino Mechanism in an $SU(3)_L\times U(1)_N$ Gauge


  By using the $L_e$ - $L_\mu$ - $L_\tau$ symmetry, we construct an
$SU(3)_L\times U(1)_N$ gauge model that provides two-loop radiative neutrino
masses as well as one-loop radiative neutrino masses. The generic smallness of
two-loop neutrino masses leading to $\Delta m^2_\odot$ compared with one-loop
neutrino masses leading to $\Delta m^2_{atm}$ successfully explains $\Delta
m^2_{atm}$ $>>$ $\Delta m^2_{\odot}$ by invoking the $L_e$ - $L_\mu$ - $L_\tau$
breaking. The Higgs scalar ($h^+$) that initiates radiative mechanisms is
unified into a Higgs triplet together with the standard Higgs scalar ($\phi^+$,
$\phi^0$) to form ($\phi^+$, $\phi^0$, $h^+$), which calls for three families
of lepton triplets: ($\nu^i_L$, $\ell^i_L$, $\omega^i_L$) (i = 1,2,3), where
$\omega^i$ denote heavy neutral leptons. The two-loop radiative mechanism is
found possible by introducing a singly charged scalar, which couples to
$\ell^i_R\omega^j_R$ (i,j = 2,3).

</DOC>
<DOC>
<DOCNO> 10786 </DOCNO>
Coexistence of charge density waves, bond order waves and spin density


  Charge, spin, as well as lattice instabilities are investigated in isolated
or weakly coupled chains of correlated electrons at quarter-filling. Our
analysis is based on extended Hubbard models including nearest neighbor
repulsion and Peierls coupling to lattice degrees of freedom. While treating
the electronic quantum fluctuations exactly, the lattice structure is optimized
self-consistently. We show that, generically, isolated chains undergo
instabilities towards coexisting charge density waves (CDW) and bond order
waves (BOW) insulating spin-gapped phases. The spin and charge gaps of the
BOW-CDW phase are computed. In the presence of an interchain magnetic coupling
spin density waves phases including a CDW or a BOW component are also found.
Our results are discussed in the context of insulating charge transfer salts.

</DOC>
<DOC>
<DOCNO> 120710 </DOCNO>
The Radio Structure of the Supernova Remnant MSH14-63


  G315.4-2.3 is an extended shell supernova remnant (SNR) with some
characteristics of evolutionarily young remnants and some of older ones. To
further elucidate some of its characteristics, we present imaging and
polarimetry of this SNR at a frequency of 1.34 GHz with a resolution of 8
arcsec made with the Australia Telescope Compact Array.
  The indicators of youth are: Morphologically, the radio emission arises in a
smooth shell without the fine scale filaments seen in the optical. Many of the
optical filaments are Balmer dominated. Where measurable, the orientation of
the magnetic field appears to be radial with respect to the center of the
remnant. There may have been a supernova in that region in AD185.
  Indications of older age include: Particularly in RCW86, the bright optical
nebula in the southwestern corner of this extended SNR, but also in other
locations there are several filaments with bright [S II] emission
representative of older shocked filaments in radiative equilibrium. If the
remnant lies at the kinematical distance of 2.8 kpc, it has a diameter of 37 pc
which would be large for a remnant less than two thousand years old.
  The remnant seems to be expanding inside a cavity outlined by infrared
emission and so it could well be young and large. Where it is encountering the
walls of the cavity it is slowing rapidly and we observe the radiative
filaments. RCW86 itself is encountering a dense clump of material but may also
be the remains of a more compact lump of ejecta ploughing into the
surroundings.

</DOC>
<DOC>
<DOCNO> 119518 </DOCNO>
Early Results from the Chandra X-ray Observatory


  We present some early results on AGN from the Chandra X-ray Observatory,
highlighting high resolution spectroscopy using the High Energy Transmission
Grating Spectrometer (HETGS). The quasar PKS 0637-752 was found to have a very
bright X-ray jet whose shape is remarkably similar to that of the radio jet on
a size scale of 100 kpc, but the X-ray emission is still inexplicably bright.
Two BL Lac objects, PKS 2155-304 and Mrk 421, observed with the spectrometer
were found to have no strong absorption or emission features. Other radio loud
AGN observed with the HETGS show simple power law spectra without obvious
features.

</DOC>
<DOC>
<DOCNO> 69220 </DOCNO>
Hagedorn inflation of D-branes


  We examine the cosmological effects of the Hagedorn phase in models where the
observable universe is pictured as a D-brane. It is shown that, even in the
absence of a cosmological constant, winding modes cause a negative `pressure'
that can drive brane inflation of various types including both power law and
exponential. We also find regimes in which the cosmology is stable but
oscillating (a bouncing universe) with the Hagedorn phase softening the
singular behavior associated with the collapse.

</DOC>
<DOC>
<DOCNO> 70331 </DOCNO>
A new determination of the QED coupling alpha(M_Z^2) lets the Higgs off


  We use the available data on e+ e- -> hadrons to determine the value of the
QED coupling at the Z pole. The inclusion of recent preliminary BES-II data in
the analysis is found to reduce the ambiguity in the determination of the
coupling, particularly that arising from the use of either exclusive or
inclusive data in the energy region \sqrt{s} < 2 GeV, in favour of a larger
value of \alpha(M_Z^2)^{-1} = 128.978 +/- 0.027. As a consequence the predicted
value of the mass of the (Standard Model) Higgs boson is increased, so that the
preferred value is just above the LEP2 bound.

</DOC>
<DOC>
<DOCNO> 100775 </DOCNO>
Constructive Field Theory and Applications: Perspectives and Open


  In this paper we review many interesting open problems in mathematical
physics which may be attacked with the help of tools from constructive field
theory. They could give work for future mathematical physicists trained with
the constructive methods well within the 21st century.

</DOC>
<DOC>
<DOCNO> 152008 </DOCNO>
A Class of N=1 Supersymmetric RG Flows from Five-dimensional N = 8


  We consider the holographic dual of a general class of N=1* flows in which
all three chiral multiplets have independent masses, and in which the
corresponding Yang-Mills scalars can develop particular
supersymmetry-preserving vevs. We also allow the gaugino to develop a vev. This
leads to a six parameter subspace of the supergravity scalar action, and we
show that this is a consistent truncation, and obtain a superpotential that
governs the N=1* flows on this subspace. We analyse some of the structure of
the superpotential, and check consistency with the asymptotic behaviour near
the UV fixed point. We show that the dimensions of the six couplings obey a sum
rule all along the N=1* flows. We also show how our superpotential describes
part of the Coulomb branch of the non-trivial N=1 fixed point theory.

</DOC>
<DOC>
<DOCNO> 100459 </DOCNO>
Realizations of quantum hom-spaces, invariant theory and quantum


  For a Hecke operator $R$, one defines the matrix bialgebra $\E_R$, which is
considered as the function algebra on the quantum space of endomorphisms of the
quantum space associated to $R$. One generalizes this notion, defining the
function algebra $\M_{RS}$ on the quantum space of homomorphisms of two quantum
spaces associated to two Hecke operators $R$ and $S$ respectively. $\M_{RS}$
can be considered as a quantum analogue (or a deformation) of the function
algebra on the variety of matrices of a certain degree. We provide two
realiztions of $\M_{RS}$ as a quotient algebra and as a subalgebra of a tensor
algebra, whence derive interesting informations about $\M_{RS}$, for instance
the Koszul property, a formula for computing the Poincar\'e series. On
$\M_{RS}$ coact the bialgebras $\E_R$ and $\E_S$. We study the two-sided ideals
in $\M_{RS}$, invariant with respect to these actions, in particular, the
determinantal ideals. We prove analogies of the fundamental theorems on
invariant theory for these quantum groups and quantum hom-spaces.

</DOC>
<DOC>
<DOCNO> 99285 </DOCNO>
Elements of a Global Operator Approach to Wess-Zumino-Novikov-Witten


  Elements of a global operator approach to the WZNW models for compact Riemann
surfaces of arbitrary genus g with N marked points were given by Schlichenmaier
and Sheinman. This contribution reports on the results. The approach is based
on the multi-point Krichever-Novikov algebras of global meromorphic functions
and vector fields, and the global algebras of affine type and their
representations. Using the global Sugawara construction and the identification
of a certain subspace of the vector field algebra with the tangent space to the
moduli space of the geometric data, Knizhnik-Zamalodchikov equations are
defined. Some steps of the approach of Tsuchia, Ueno and Yamada to WZNW models
are presented to compare it with our approach.

</DOC>
<DOC>
<DOCNO> 70244 </DOCNO>
Testing MEM with Diquark and thermal Meson Correlation Functions


  When applying the maximum entropy method (MEM) to the analysis of hadron
correlation functions in QCD a central issue is to understand to what extent
this method can distinguish bound states, resonances and continuum
contributions to spectral functions. We discuss these issues by analyzing meson
and diquark correlation functions at zero temperature as well as free quark
anti-quark correlators. The latter test the applicability of MEM to high
temperature QCD.

</DOC>
<DOC>
<DOCNO> 69329 </DOCNO>
Signatures of heavy Majorana neutrinos and HERA's isolated lepton events


  The graph of neutrinoless double beta decay is applied to HERA and
generalized to final states with any two charged leptons. Considered is the
case in which one of the two escapes typical identification criteria and the
case when a produced tau decays hadronically. Both possibilities give one
isolated lepton with high transverse momentum, hadronic activity and an
imbalance in transverse momentum. We examine the kinematical properties of
these events and compare them with the high p_T isolated leptons reported by
the H1 collaboration. Their positive charged muon events can be explained by
the ``double beta'' process and we discuss possibilities for the precise
determination which original final state produced the single isolated lepton.
To confirm our hypothesis one should search in the data for high pseudorapidity
and/or low p_T leptons or for additional separated jets.

</DOC>
<DOC>
<DOCNO> 151406 </DOCNO>
Noncommutative spheres and the AdS/CFT correspondence


  We present direct arguments for non-commutativity of spheres in the AdS/CFT
correspondence. The discussion is based on results for the $S_N$ orbifold SCFT.
Concentrating on three point correlations (at finite $N$) we exhibit a
comparison with correlations on a non-commutative sphere. In this manner an
essential signature of non-commutativity is identified giving further support
for the original proposal of hep-th/9902059.

</DOC>
<DOC>
<DOCNO> 85609 </DOCNO>
Continuous matter fields in Regge calculus


  We find that the continuous matter fields are ill-defined in Regge calculus
in the physical 4D theory since the corresponding effective action has infinite
terms unremovable by the UV renormalisation procedure. These terms are
connected with the singular nature of the curvature distribution in Regge
calculus, namely, with the presence in d>2 dimensions of the
(d-3)-dimensional simplices where the (d-2)-dimensional ones carrying different
conical singularities are meeting. Possible resolution of this difficulty is
discretisation of matter fields in Regge background.

</DOC>
<DOC>
<DOCNO> 120565 </DOCNO>
The optical reflector system for the CANGAROO-II imaging atmospheric


  A new imaging atmospheric Cherenkov telescope (CANGAROO-II) with a
light-weight reflector has been constructed. Light, robust, and durable mirror
facets of containing CFRP (Carbon Fiber Reinforced Plastic) laminates were
developed for the telescope. The attitude of each facet can be adjusted by
stepping motors. In this paper, we describe the design, manufacturing,
alignment procedure, and the performance of the CANGAROO-II optical reflector
system.

</DOC>
<DOC>
<DOCNO> 84773 </DOCNO>
Differentially rotating disks of dust: Arbitrary rotation law


  In this paper, solutions to the Ernst equation are investigated that depend
on two real analytic functions defined on the interval [0,1]. These solutions
are introduced by a suitable limiting process of Backlund transformations
applied to seed solutions of the Weyl class. It turns out that this class of
solutions contains the general relativistic gravitational field of an arbitrary
differentially rotating disk of dust, for which a continuous transition to some
Newtonian disk exists. It will be shown how for given boundary conditions (i.
e. proper surface mass density or angular velocity of the disk) the
gravitational field can be approximated in terms of the above solutions.
Furthermore, particular examples will be discussed, including disks with a
realistic profile for the angular velocity and more exotic disks possessing two
spatially separated ergoregions.

</DOC>
<DOC>
<DOCNO> 152582 </DOCNO>
On the "Universal" N=2 Supersymmetry of Classical Mechanics


  In this paper we continue the study of the geometrical features of a
functional approach to classical mechanics proposed some time ago. In
particular we try to shed some light on a N=2 "universal" supersymmetry which
seems to have an interesting interplay with the concept of ergodicity of the
system. To study the geometry better we make this susy local and clarify
pedagogically several issues present in the literature. Secondly, in order to
prepare the ground for a better understanding of its relation to ergodicity, we
study the system on constant energy surfaces. We find that the procedure of
constraining the system on these surfaces injects in it some local grassmannian
invariances and reduces the N=2 global susy to an N=1.

</DOC>
<DOC>
<DOCNO> 10562 </DOCNO>
Distribution of the k-th smallest Dirac operator eigenvalue


  Based on the exact relationship to Random Matrix Theory, we derive the
probability distribution of the k-th smallest Dirac operator eigenvalue in the
microscopic finite-volume scaling regime of QCD and related gauge theories.

</DOC>
<DOC>
<DOCNO> 8381 </DOCNO>
Spin and link overlaps in 3-dimensional spin glasses


  Excitations of three-dimensional spin glasses are computed numerically. We
find that one can flip a finite fraction of an LxLxL lattice with an O(1)
energy cost, confirming the mean field picture of a non-trivial spin overlap
distribution P(q). These low energy excitations are not domain-wall-like,
rather they are topologically non-trivial and they reach out to the boundaries
of the lattice. Their surface to volume ratios decrease as L increases and may
asymptotically go to zero. If so, link and window overlaps between the ground
state and these excited states become ``trivial''.

</DOC>
<DOC>
<DOCNO> 68213 </DOCNO>
Graviscalars from higher-dimensional metrics and curvature-Higgs mixing


  We investigate the properties of scalar fields arising from gravity
propagating in extra dimensions. In the scenario of large extra dimensions,
proposed by Arkani-Hamed, Dimopoulos and Dvali, graviscalar Kaluza-Klein
excitations are less important than the spin-2 counterparts in most processes.
However, there are important exceptions. The Higgs boson can mix to these
particles by coupling to the Ricci scalar. Because of the large number of
states involved, this mixing leads, in practice, to a sizeable invisible width
for the Higgs. In the Randall-Sundrum scenario, the only graviscalar is the
radion. It can be produced copiously at hadron colliders by virtue of its
enhanced coupling to two gluons through the trace anomaly of QCD. We study both
the production and decay of the radion, and compare it to the Standard Model
Higgs boson. Furthermore, we find that radion detectability depends crucially
on the curvature-Higgs boson mixing parameter.

</DOC>
<DOC>
<DOCNO> 170253 </DOCNO>
Note on reversibility of quantum jumps


  It has been recently proved that a quantum jump may be reversed by a unitary
process provided the initial state is restricted by some conditions. The
application of such processes for preventing decoherence, for example in
quantum computers, was suggested. We shall show that in the situation when the
quantum jump is reversible it supplies no information about the initial state
additional to the information known beforehand. Therefore the reversibility of
this type does not contradict the general statement of quantum measurement
theory: a measurement cannot be reversed. As a consequence of this, the
coherence of a state (say, in a quantum computer) cannot be restored after it
is destroyed by dissipative processes having a character of measurement.

</DOC>
<DOC>
<DOCNO> 9210 </DOCNO>
Multifractality in Time Series


  We apply the concepts of multifractal physics to financial time series in
order to characterize the onset of crash for the Standard & Poor's 500 stock
index x(t). It is found that within the framework of multifractality, the
"analogous" specific heat of the S&P500 discrete price index displays a
shoulder to the right of the main peak for low values of time lags. On
decreasing T, the presence of the shoulder is a consequence of the peaked,
temporal x(t+T)-x(t) fluctuations in this regime. For large time lags (T>80),
we have found that C_{q} displays typical features of a classical phase
transition at a critical point. An example of such dynamic phase transition in
a simple economic model system, based on a mapping with multifractality
phenomena in random multiplicative processes, is also presented by applying
former results obtained with a continuous probability theory for describing
scaling measures.

</DOC>
<DOC>
<DOCNO> 80582 </DOCNO>
Review of Unquenched Results


  One of the major frontiers of lattice field theory is the inclusion of light
fermions in simulations, particularly in pursuit of accurate, first principles
predictions from lattice QCD. With dedicated Teraflops-scale computers
currently simulating QCD, another step towards precision full QCD simulations
is underway. In addition to ongoing staggered and Wilson fermion simulations,
first results from full QCD with domain wall fermions are available. After some
discussion of work toward better algorithms, simulations completed to date will
be discussed.

</DOC>
<DOC>
<DOCNO> 71319 </DOCNO>
Resummation and damping in the O(N) model


  In this talk I summarize the one loop and higher loop calculations of the
effective equations of motion of the O(N) symmetric scalar model in the linear
response approximation. At one loop one finds essential difference in long time
behavior for the fields below and above a dynamically generated length scale. A
partial resummation assuming quasi-particle propagation seems to cancel the
relevance of this scale.

</DOC>
<DOC>
<DOCNO> 150513 </DOCNO>
Holomorphy, Minimal Homotopy and the 4D, N = 1 Supersymmetric


  By use of a special homotopy operator, we present an explicit, closed-form
and simple expression for the left-right Bardeen-Gross-Jackiw anomalies
described as the proper superspace integral of a superfunction.

</DOC>
<DOC>
<DOCNO> 120540 </DOCNO>
Active Galactic Nuclei in the CNOC2 Field Galaxy Redshift Survey


  We present a sample of 47 confirmed and 14 candidate Active Galactic Nuclei
(AGN) discovered in the Canadian Network for Observational Cosmology field
galaxy redshift survey (CNOC2). The sample consists of 38 objects identified
from broad emission lines, 8 from narrow [NeV] emission, and 15 candidates from
FeII or MgII absorption lines, one of which has been confirmed as a broad-line
AGN via infrared spectroscopy. Redshifts of these AGN range from z=0.27 to
z=4.67, and the average absolute magnitude is M_B=-22.25. No color selection
criteria were involved in selecting this spectroscopically discovered sample.
The sample is also unbiased against objects with luminous host galaxies since
the spectroscopy preferentially targeted extended objects. Simple color-color
diagram selection criteria can recover 81+-6% of the CNOC2 AGN, but several of
the most unusual objects would be missing from such a color-selected sample. In
the subsample with broad emission lines, the average equivalent widths for MgII
and CIII] agree with the predictions of previous studies of the Baldwin effect.
However, the average equivalent widths for CIV and Ly-alpha are smaller than
predicted by previous studies of the Baldwin effect at lower redshift. This may
imply that the slopes of the CIV and Ly-alpha Baldwin effects evolve with
redshift, steepening with cosmic time. The broad emission line AGN also show a
higher incidence of associated MgII and CIV absorption than in most previous
surveys. This may arise from strong absorption being anti-correlated with
optical luminosity or becoming less frequent with cosmic time, or possibly
because our selection method is not biased against objects with resolved
spatial structure or reddened by dust associated with the absorbing gas.
(Abridged)

</DOC>
<DOC>
<DOCNO> 84089 </DOCNO>
Time Dispersion and Efficiency of Detection for Signals in Gravitational


  Using simulated signals and measured noise with the EXPLORER and NAUTILUS
detectors we find the efficiency of signal detection and the signal arrival
time dispersion versus the signal-to-noise ratio.

</DOC>
<DOC>
<DOCNO> 39818 </DOCNO>
High pt charged-pion production in Pb-Au collisions at 158AGeV/c


  The CERES/Na45 experiment at CERN SPS measured transverse momentum spectra of
charged-pions in the range 1<pt<4GeV/c near mid-rapidity in 158 AGeV/c Pb-Au
collisions. The invariant transverse momentum spectra are exponential over the
entire observed range. The average inverse slope is 245+/- 5MeV/c, it shows a
2.4% increase with centrality of the collision over the 35% most central
fraction of the cross section. The pi-/pi+ ratio is constant at 1.028+/-0.005
over the pt interval measured.

</DOC>
<DOC>
<DOCNO> 122259 </DOCNO>
Dynamical Evolution of Protoplanetary Disks


  This paper reviews the theory of protostellar debris disks. After a brief
introduction to accretion disk physics, I describe coagulation models of planet
formation in the outer regions of planetesimal disks. Coagulation models for
the Kuiper Belt produce Pluto-sized objects on timescales of 10-40 Myr. These
models yield size distributions which agree with observations of Kuiper Belt
objects with red magnitudes, R = 20-27. Velocity stirring models for other
debris disk systems demonstrate that 500 km or larger objects can stir the
velocities of small objects up to the shattering limit needed to begin a
collisional cascade.

</DOC>
<DOC>
<DOCNO> 67721 </DOCNO>
Baryon Number Conservation and Statistical Production of Antibaryons


  The statistical production of antibaryons is considered within the canonical
ensemble formulation. We demonstrate that the antibaryon suppression in small
systems due to the exact baryon number conservation is rather different in the
baryon-free (B=0) and baryon-rich (B>1) systems. At constant values of
temperature and baryon density in the baryon-rich systems the density of the
produced antibaryons is only weakly dependent on the size of the system. For
realistic hadronization conditions this dependence appears to be close to
B/(B+1) which is in agreement with the preliminary data of the NA49
Collaboration for the antiproton/pion ratio in nucleus-nucleus collisions at
the CERN SPS energies. However, a consistent picture of antibaryon production
within the statistical hadronization model has not yet been achieved. This is
because the condition of constant hadronization temperature in the baryon-free
systems leads to a contradiction with the data on the antiproton/pion ratio in
e+e- interactions.

</DOC>
<DOC>
<DOCNO> 11282 </DOCNO>
Electronic Stopping and Momentum Density of Diamond Obtained from


  We calculate the "head" element or the (0,0)-element of the wave-vector and
frequency-dependent dielectric matrix of bulk crystals via first-principles,
all-electron Kohn-Sham states in the integral of the irreducible polarizability
in the random phase approximation. We approximate the macroscopic "head"
element of the inverse matrix by its reciprocal value, and integrate over
frequencies and momenta to obtain the electronic energy loss of protons at low
velocities. Numerical evaluation for diamond targets predicts that the band gap
causes a strong non-linear reduction of the electronic stopping power at ion
velocities below 0.2 atomic units.

</DOC>
<DOC>
<DOCNO> 178837 </DOCNO>
Asymmetry Effects on Nuclear Fragmentation


  We show the possibility of extracting important information on the symmetry
term of the Equation of State ($EOS$) directly from multifragmentation
reactions using stable isotopes with different charge asymmetries. We study
n-rich and n-poor $Sn + Sn$ collisions at $50AMeV$ using a new stochastic
transport approach with all isospin effects suitably accounted for. For central
collisions a chemical component in the spinodal instabilities is clearly seen.
This effect is reduced in the neck fragmentation observed for semiperipheral
collisions, pointing to a different nature of the instability. In spite of the
low asymmetry tested with stable isotopes the results are showing an
interesting and promising dependence on the stiffness of the symmetry term,
with an indication towards an increase of the repulsion above normal density.

</DOC>
<DOC>
<DOCNO> 69980 </DOCNO>
Single Top Quark in the SM and Beyond


  The prospects of single top quark physics at colliders of the TeV energy
scale are discussed. Single top quark study allows a direct measurement of the
$Wtb$ vertex and a precise probing physics beyond the Standard Model in various
scenarios.

</DOC>
<DOC>
<DOCNO> 99858 </DOCNO>
On two-parameter deformations of $osp(1|2)^(1)$


  An elliptic two-parameter deformation of the (universal enveloping
superalgebra of) affine Lie superalgebra $osp(1|2)^{(1)}$ is proposed in terms
of free boson realization. This deformed superalgebra is shown to fit in the
framework of infinite Hopf family of superalgebras, a generalization of the
infinite Hopf family of algebras proposed earlier by the authors. The
trigonometric and rational degenerations are briefly discussed.

</DOC>
<DOC>
<DOCNO> 84383 </DOCNO>
Boost-rotation symmetric type D radiative metrics in Bondi coordinates


  The asymptotic properties of the solutions to the Einstein-Maxwell equations
with boost-rotation symmetry and Petrov type D are studied. We find series
solutions to the pertinent set of equations which are suitable for a late time
descriptions in coordinates which are well adapted for the description of the
radiative properties of spacetimes (Bondi coordinates). By calculating the
total charge, Bondi and NUT mass and the Newman-Penrose constants of the
spacetimes we provide a physical interpretation of the free parameters of the
solutions. Additional relevant aspects on the asymptotics and radiative
properties of the spacetimes considered, such as the possible polarization
states of the gravitational and electromagnetic field, are discussed through
the way.

</DOC>
<DOC>
<DOCNO> 120866 </DOCNO>
The Disk and Dark Halo Mass of the Barred Galaxy NGC 4123. II.


  We report a dynamical determination of the separate contributions of disk and
dark halo masses to the rotation curve of a spiral galaxy. We use
fluid-dynamical models of gas flow in the barred galaxy NGC 4123 to constrain
the dynamical properties of the galaxy: disk M/L, bar pattern speed, and the
central density and scale radius of the dark halo. We derive a realistic barred
potential directly from the light distribution. For each model we assume a
value of the stellar M/L and a bar pattern speed Omega_p and add a dark halo to
fit the rotation curve. We then compute the gas flow velocities with a 2-D gas
dynamical code, and compare the model flow patterns to a 2-D velocity field
derived from Fabry-Perot observations. The strong shocks and non-circular
motions in the observed gas flow require a high stellar M/L and a fast-rotating
bar. Models with I-band disk M/L of 2.0 -- 2.5 h_75, or 80 -- 100% of the
maximum disk value, are highly favored. The corotation radius of the bar must
be <= 1.5 times the bar semi-major axis. These results contradict some recent
claimed ``universal'' galaxy disk/halo relations, since NGC 4123 is of modest
size (rotation curve maximum 145 km/sec, and V_flat = 130 km/sec) yet is quite
disk-dominated. The dark halo of NGC 4123 is less concentrated than favored by
current models of dark halos based on cosmological simulations. Since some 30%
of bright disk galaxies are strongly barred and have dust lanes indicating
shock morphology similar to that of NGC 4123, it is likely that they also have
high stellar M/L and low density halos. We suggest that luminous matter
dominates inside the optical radius R_25 of high surface brightness disk
galaxies.

</DOC>
<DOC>
<DOCNO> 118749 </DOCNO>
The MACHO Project: Microlensing Detection Efficiency


  The MACHO project is a search for dark matter in the form of massive compact
halo objects (MACHOs). The project has photometrically monitored tens of
millions of stars in the Large Magellanic Cloud (LMC), Small Magellanic Cloud
(SMC), and Galactic bulge in search of rare gravitational microlensing events
caused by these otherwise invisible objects. In 5.7 years of observations
toward the LMC some 13-17 microlensing events have been observed by the MACHO
survey, allowing powerful statements to be made about the nature of the dark
population in the halo of our Galaxy. A critical component of these statements
is an accurate determination of the survey's detection efficiency. The
detection efficiency is a complicated function of temporal sampling, stellar
crowding (the luminosity function), image quality, photometry, time-series
analysis, and criteria used to select the microlensing candidates. Such a
complex interdependence is most naturally solved using a Monte Carlo approach.
Here we describe the details of the Monte Carlo used to calculate the
efficiency presented in the MACHO 5.7-year LMC results. Here we correct several
shortcomings of past determinations, including (1) adding fainter source stars
(2.5 magnitudes below our faintest detected "stars"), (2) an up-to-date
luminosity function for the LMC, (3) better sampling of real images in both
stellar density and observing conditions, (4) an improved scheme for adding
artificial microlensing onto a random sample of real lightcurves, and many
other improvements. [Abridged]

</DOC>
<DOC>
<DOCNO> 9831 </DOCNO>
Effects of arbitrarily directed field on spin phase oscillations in


  Quantum phase interference and spin-parity effects are studied in biaxial
molecular magnets in a magnetic field at an arbitrarily directed angle. The
calculations of the ground-state tunnel splitting are performed on the basis of
the instanton technique in the spin-coherent-state path-integral
representation, and complemented by exactly numerical diagonalization. Both the
Wentzel-Kramers-Brillouin exponent and the preexponential factor are obtained
for the entire region of the direction of the field. Our results show that the
tunnel splitting oscillates with the field for the small field angle, while for
the large field angle the oscillation is completely suppressed. This distinct
angular dependence, together with the dependence of the tunnel splitting on the
field strengh, provide an independent test for spin-parity effects in biaxial
molecular magnets. The analytical results for the molecular Fe$_{8}$ magnet,
are found to be in good areement with the numerical simulations, which suggests
that even the molecular magnet with total spin S=10 is large enough to be
treated as a giant spin system.

</DOC>
<DOC>
<DOCNO> 118162 </DOCNO>
The Contribution of Faint Blue Galaxies to the Sub-mm Counts and


  Observations in the submillimetre waveband have recently revealed a new
population of luminous, sub-mm sources. These are proposed to lie at high
redshift and to be optically faint due to their high intrinsic dust
obscuration. The presence of dust has been previously invoked in optical galaxy
count models which assume $\tau=9$ Gyr Bruzual & Charlot evolution for spirals
and these fit the count data well from U to K. We now show that by using either
a 1/$\lambda$ or Calzetti absorption law for the dust and re-distributing the
evolved spiral galaxy UV radiation into the far infra-red(FIR), these models
can account for all of the `faint'($\leq1$mJy) $850\mu$m galaxy counts, but
fail to fit 'bright'($\ge2$mJy) sources, indicating that another explanation
for the sub-mm counts may apply at brighter fluxes(e.g. QSOs, ULIRGs). We find
that the main contribution to the faint, sub-mm number counts is in the
redshift range $0.5 < z < 3$, peaking at $z\approx 1.8$. The above model, using
either dust law, can also explain a significant proportion of the
extra-galactic background at $850\mu$m as well as producing a reasonable fit to
the bright $60\mu m$ IRAS counts.

</DOC>
<DOC>
<DOCNO> 102260 </DOCNO>
Transmutation kernels for the little q-Jacobi function transform


  The little q-Jacobi function transform depends on three parameters. An
explicit expression as a sum of two very-well-poised 8W7-series is derived for
the dual transmutation kernel (a kind of non-symmetric Poisson kernel) relating
little q-Jacobi function transforms for different parameter sets. A product
formula for the dual transmutation kernel is obtained. For the inverse
transform the transmutation kernel is given as a 3\phi2-series, and a product
formula as a finite sum is derived. The transmutation kernel gives rise to
intertwining operators for the second order hypergeometric q-difference
operator, which generalise the intertwining operators arising from a Darboux
factorisation.

</DOC>
<DOC>
<DOCNO> 123049 </DOCNO>
Singular Isothermal Disks: II. Nonaxisymmetric Bifurcations and


  We review the difficulties of the classical fission and fragmentation
hypotheses for the formation of binary and multiple stars. A crucial missing
ingredient in previous theoretical studies is the inclusion of dynamically
important levels of magnetic fields. As a minimal model for a candidate
presursor to the formation of binary and multiple stars, we therefore formulate
and solve the problem of the equilibria of isopedically magnetized, singular
isothermal disks, without the assumption of axial symmetry. Considerable
analytical progress can be made if we restrict our attention to models that are
scale-free, i.e., that have surface densities that vary inversely with distance
from the rotation axis of the system. In agreement with earlier analysis by
Syer and Tremaine, we find that lopsided (M=1) configurations exist at any
dimensionless rotation rate, including zero. Multiple-lobed (M = 2, 3, 4, ...)
configurations bifurcate from an underlying axisymmetric sequence at
progressively higher dimensionless rates of rotation, but such nonaxisymmetric
sequences always terminate in shockwaves before they have a chance to fission
into M=2, 3, 4, ... separate bodies. On the basis of our experience in this
paper, and the preceding Paper I, we advance the hypothesis that binary and
multiple star-formation from smooth (i.e., not highly turbulent) starting
states that are supercritical but in unstable mechanical balance requires the
rapid (i.e., dynamical) loss of magnetic flux at some stage of the ensuing
gravitational collapse.

</DOC>
<DOC>
<DOCNO> 39865 </DOCNO>
Strong Coupling Constant from Scaling Violations in Fragmentation


  We present a new determination of the strong coupling constant alpha_s
through the scaling violations in the fragmentation functions for charged
pions, charged kaons, and protons. In our fit we include the latest e+e-
annihilation data from CERN LEP1 and SLAC SLC on the Z-boson resonance and
older, yet very precise data from SLAC PEP at center-of-mass energy sqrt(s)=29
GeV. A new world average of alpha_s is given.

</DOC>
<DOC>
<DOCNO> 121973 </DOCNO>
The Chemical Evolution of Galaxy Disks


  We discuss the main ingredients necessary to build models of chemical
evolution of spiral galaxies and in particular the Milky Way galaxy. These
ingredients include: the star formation rate, the initial mass function, the
stellar yields and the gas flows. Then we discuss models for the chemical
evolution of galaxy disks and compare their predictions with the main
observational constraints available for the Milky Way and other spirals. We
conclude that it is very likely that the disk of our Galaxy and other spirals
formed through an ``inside-out'' mechanism, where the central parts collapsed
much faster than the external ones. This mechanism has important consequences
for the appearance of galaxy disks as a function of redshift.

</DOC>
<DOC>
<DOCNO> 151638 </DOCNO>
A Survey of Star Product Geometry


  A brief pedagogical survey of the star product is provided, through
Groenewold's original construction based on the Weyl correspondence. It is then
illustrated how simple Landau orbits in a constant magnetic field, through
their Dirac Brackets, define a noncommutative structure since these brackets
exponentiate to a star product---a circumstance rarely operative for generic
Dirac Brackets. The geometric picture of the star product based on its Fourier
representation kernel is utilized in the evaluation of chains of star products.
The intuitive appreciation of their associativity and symmetries is thereby
enhanced. This construction is compared and contrasted with the remarkable
phase-space polygon construction of Almeida.

</DOC>
<DOC>
<DOCNO> 169933 </DOCNO>
Quantum games and quantum algorithms


  A quantum algorithm for an oracle problem can be understood as a quantum
strategy for a player in a two-player zero-sum game in which the other player
is constrained to play classically. I formalize this correspondence and give
examples of games (and hence oracle problems) for which the quantum player can
do better than would be possible classically. The most remarkable example is
the Bernstein-Vazirani quantum search algorithm which I show creates no
entanglement at any timestep.

</DOC>
<DOC>
<DOCNO> 10498 </DOCNO>
Breaking of scale-invariance symmetry in adsorption processes


  Standard models of sequential adsorption are implicitly formulated in a {\em
scale invariant} form, by assuming adsorption on an infinite surface, with no
characteristic length scales. In real situations, however, involving complex
surfaces, intrinsic length scales may be relevant. We present an analytic model
of continuous random sequential adsorption, in which the scale invariance
symmetry is explicitly broken. The characteristic length is imposed by a set of
scattered obstacles, previously adsorbed onto the surface. We show, by means of
analytic solutions and numerical simulations, the profound effects of the
symmetry breaking on both the jamming limit and the correlation function of the
adsorbed layer.

</DOC>
<DOC>
<DOCNO> 11367 </DOCNO>
Anomalous Larmour Frequency Dependence of Proton Spin-Lattice Relaxation


  We report here the results of $^1$H NMR spin-lattice relaxation time (T$_1$)
studies in Glycine phosphite which is a ferroelectric below 224 K. The
experiments have been carried out in the temperature range from 200 K to 419 K
and at two Larmour frequencies of 11.40MHz and 23.56 MHz. We have noticed a
Larmour frequency dependence on the high temperature side of the T$_1$ minimum
>. A model is proposed based on the BPP theory to explain the observation.

</DOC>
<DOC>
<DOCNO> 100271 </DOCNO>
The cubic chessboard


  We present a survey of recent results, scattered in a series of papers that
appeared during past five years, whose common denominator is the use of cubic
relations in various algebraic structures. Cubic (or ternary) relations can
represent different symmetries with respect to the permutation group S_3, or
its cyclic subgroup Z_3. Also ordinary or ternary algebras can be divided in
different classes with respect to their symmetry properties. We pay special
attention to the non-associative ternary algebra of 3-forms (or ``cubic
matrices''), and Z_3-graded matrix algebras. We also discuss the Z_3-graded
generalization of Grassmann algebras and their realization in generalized
exterior differential forms. A new type of gauge theory based on this
differential calculus is presented. Finally, a ternary generalization of
Clifford algebras is introduced, and an analog of Dirac's equation is
discussed, which can be diagonalized only after taking the cube of the
Z_3-graded generalization of Dirac's operator. A possibility of using these
ideas for the description of quark fields is suggested and discussed in the
last Section.

</DOC>
<DOC>
<DOCNO> 122272 </DOCNO>
On the Size-Dependence of the Inclination Distribution of the Main


  We present a new analysis of the currently available orbital elements for the
known Kuiper belt objects. In the non-resonant, main Kuiper belt we find a
statistically significant relationship between an object's absolute magnitude
(H) and its inclination (i). Objects with H<6.5 (i.e. radii >~170 km for a 4%
albedo) have higher inclinations than those with H>6.5 (radii >~ 170 km). We
have shown that this relationship is not caused by any obvious observational
bias. We argue that the main Kuiper belt consists of the superposition of two
distinct distributions. One is dynamically hot with inclinations as large as
\~35 deg and absolute magnitudes as bright as 4.5; the other is dynamically cold
with i<~5 deg and H>6.5. The dynamically cold population is most likely
dynamically primordial. We speculate on the potential causes of this
relationship.

</DOC>
<DOC>
<DOCNO> 178406 </DOCNO>
Three-cluster nuclear molecules


  A three-center phenomenological model able to explain, at least from a
qualitative point of view, the difference in the observed yield of a
particle-accompanied fission and that of binary fission was developed. It is
derived from the liquid drop model under the assumption that the aligned
configuration, with the emitted particle between the light and heavy fragment
is obtained by increasing continuously the separation distance, while the radii
of the light fragment and of the light particle are kept constant. During the
first stage of the deformation one has a two-center evolution until the neck
radius becomes equal to the radius of the emitted particle. Then the three
center starts developing by decreasing with the same amount the two tip
distances. In such a way a second minimum, typical for a cluster molecule,
appears in the deformation energy. Examples are presented for $^{240}$Pu parent
nucleus emitting $\alpha$-particles and $^{14}$C in a ternary process.

</DOC>
<DOC>
<DOCNO> 10609 </DOCNO>
Chiral non-linear sigma-models as models for topological


  We study the mechanism of topological superconductivity in a hierarchical
chain of chiral non-linear sigma-models (models of current algebra) in one,
two, and three spatial dimensions. The models have roots in the 1D
Peierls-Frohlich model and illustrate how the 1D Frohlich's ideal conductivity
extends to a genuine superconductivity in dimensions higher than one. The
mechanism is based on the fact that a point-like topological soliton carries an
electric charge. We discuss a flux quantization mechanism and show that it is
essentially a generalization of the persistent current phenomenon, known in
quantum wires. We also discuss why the superconducting state is stable in the
presence of a weak disorder.

</DOC>
<DOC>
<DOCNO> 116274 </DOCNO>
Interaction of a vortex ring with the free surface of ideal fluid


  The interaction of a small vortex ring with the free surface of a perfect
fluid is considered. In the frame of the point ring approximation the
asymptotic expression for the Fourier-components of radiated surface waves is
obtained in the case when the vortex ring comes from infinity and has both
horizontal and vertical components of the velocity. The non-conservative
corrections to the equations of motion of the ring, due to Cherenkov radiation,
are derived.

</DOC>
<DOC>
<DOCNO> 122475 </DOCNO>
Optical and infrared interferometry


  Interferometric techniques are at the forefront of modern astronomical
instrumentation. A new generation of instruments are either operating or
nearing completion, including arrays of small telescopes as well as the ``big
guns'' (VLTI and Keck). A number of space interferometers for the detection of
extra-solar planets are also being planned. I review the current state of play
and describe the latest developments in the field.

</DOC>
<DOC>
<DOCNO> 100723 </DOCNO>
Singular perturbations and first order PDE on manifolds


  In this note we present some results concerning the concentration of
sequences of first eigenfunctions on the limit sets of a Morse-Smale dynamical
system on a compact Riemanniann manifold. More precisely a renormalized
sequence of eigenfunctions converges to a measure $\mu$ concentrated on the
hyperbolic sets of the field. The set of all possible measure turns out to be a
sum of a finite Dirac distributions localized at the critical point of the
field and absolutely continuous measure with respect to the Lebesgue measure on
each limit cycles : the coefficients which appear in the limit measure can be
characterized using the concentration theory. In the second part, certain
aspects of some first order PDE on manifolds are studied. We study the limit of
a sequence solutions of a second order PDE, when a parameter of viscosity tends
to zero. Under some explicit assumptions on some vector fields, bounded and
differentiable solutions are obtained. We exibit the role played by the limit
sets of the dynamical systems and provide in some cases an explicit
representation formula.

</DOC>
<DOC>
<DOCNO> 85096 </DOCNO>
Particle number density fluctuations and pressure effects on structure


  We provide a covariant and gauge-invariant approach to the question of how a
first order pressure can be incorporated self-consistently in a cosmological
scenario. The approximation is relevant, in the linear regime, to weakly
self-interacting or warm dark matter models. We also derive number density
fluctuations in which new modes appear because the number density fluctuations
are no longer simply proportional to the density fluctuations.

</DOC>
<DOC>
<DOCNO> 68708 </DOCNO>
The Neutron Electric Dipole Moment and CP-violating Couplings in the


  We analyze the neutron electric dipole moment (EDM) in the Minimal
Supersymmetric Model with explicit R-parity violating terms. The leading
contribution to the EDM occurs at the 2-loop level and is dominated by the
chromoelectric dipole moments of quarks, assuming there is no tree-level
mixings between sleptons and Higgs bosons or between leptons and gauginos.
Based on the experimental constraint on the neutron EDM, we set limits on the
imaginary parts of complex couplings ${\lambda'}_{ijk}$ and ${\lambda}_{ijk}$
due to the virtual b-loop or tau-loop.

</DOC>
<DOC>
<DOCNO> 118170 </DOCNO>
Measuring the Size of the Vela Pulsar's Radio Emission Region


  We describe measurements of the size of the Vela pulsar via scintillation,
using both fits to the distribution of intensity and measurements of the
modulation index. We briefly discuss systematic effects other than source size
that can affect the distribution, including gain variations, self-noise,
scintillation shot noise, and correlator saturation. Modulation index, a single
number, can be biased by all of these, whereas the distribution of intensity is
affected in different ways by different effects, providing means of
distinguishing among them. Self-noise and gain variations are likely more
important at long observing wavelengths, and correlator saturation and
scintillation shot noise at short wavelengths. We find a size of about 500 km
at decimeter wavelengths. Interestingly, this agrees with measurements of
modulation index by Roberts & Ables at the same wavelength. Their results (and
more recently that reported by Macquart et al.) suggest that size decreases
with increasing wavelength. Although consistent with the observations, this
conclusion is perhaps surprising from the standpoint of the traditional
radius-to-frequency mapping. However, these measurements are of size rather
than height; and of course systematic effects may play a role.

</DOC>
<DOC>
<DOCNO> 8858 </DOCNO>
Peculiarities of Raman Spectra Shape in the Disordered Ferroelectrics


  Theory of the first order Raman scattering (FOR) line shape allowing for
nonlinear and correlation effects contribution to inhomogeneous broadening as
well as dynamic mechanisms of homogeneous broadening is developed. It is shown
that in general case FOR line contains two maxima, shape of low frequency one
being defined by homogeneous broadening. Our theory explains the peculiarity of
observed FOR scattering of TO_2 hard phonon in KTL and KTN at different
temperatures and concentrations of Li and Nb ions.

</DOC>
<DOC>
<DOCNO> 69139 </DOCNO>
Discovery of Proton Decay: A Must for Theory, a Challenge for Experiment


  It is noted that, but for one missing piece -- proton decay -- the evidence
in support of grand unification is now strong. It includes: (i) the observed
family-structure, (ii) the meeting of the gauge couplings, (iii)
neutrino-oscillations, (iv) the intricate pattern of the masses and mixings of
all fermions, including the neutrinos, and (v) the need for $B-L$ as a
generator, to implement baryogenesis. Taken together, these not only favor
grand unification but in fact select out a particular route to such
unification, based on the ideas of supersymmetry, SU(4)-color and left-right
symmetry. Thus they point to the relevance of an effective string-unified
G(224) or SO(10)-symmetry.
  A concrete proposal is presented, within a predictive
SO(10)/G(224)-framework, that successfully describes the masses and mixings of
all fermions, including the neutrinos - with eight predictions, all in
agreement with observation. Within this framework, a systematic study of proton
decay is carried out, which pays special attention to its dependence on the
fermion masses, including the superheavy Majorana masses of the right-handed
neutrinos. The study shows that a conservative upper limit on the proton
lifetime is about (1/2 - 1)$\times10^{34}$ yrs, with $\overline{\nu}K^{+}$
being the dominant decay mode, and as a distinctive feature, $\mu^{+}K^{0}$
being prominent. This in turn strongly suggests that an improvement in the
current sensitivity by a factor of five to ten (compared to SuperK) ought to
reveal proton decay. Otherwise some promising and remarkably successful ideas
on unification would suffer a major setback.

</DOC>
<DOC>
<DOCNO> 116955 </DOCNO>
Energy Transfer Mechanisms and Equipartitioning in non-Equilibrium


  A process of energy transfer is demonstrated in non-equilibrium charged
particle beams with anisotropy and space charge. Equipartitioning of energy
between available degrees of freedom occurs in just a few betatron wavelengths,
without halo formation. Collective space charge modes similar to those observed
in recent experiments provide the underlying coupling mechanism. Since
laboratory beams are commonly far from equilibrium, the traditional K-V
stability analysis does not necessarily apply, implying that selection of an
operating point based on theory does not necessarily avoid equipartitioning.
Furthermore, the rate of equipartitioning is shown to depend on a single free
parameter related space charge content of the final (equipartitioned) beam, and
does not depend on how the kinetic energy is initially distributed between the
two planes.

</DOC>
<DOC>
<DOCNO> 99510 </DOCNO>
Extension dimension and C-spaces


  Some generalizations of the classical Hurewocz formula are obtained for
extension dimension and C-spaces.

</DOC>
<DOC>
<DOCNO> 100912 </DOCNO>
Towards the ample cone of $\mgn$


  In this paper we study the ample cone of the moduli space $\mgn$ of stable
$n$-pointed curves of genus $g$. Our motivating conjecture is that a divisor on
$\mgn$ is ample iff it has positive intersection with all 1-dimensional strata
(the components of the locus of curves with at least $3g+n-2$ nodes). This
translates into a simple conjectural description of the cone by linear
inequalities, and, as all the 1-strata are rational, includes the conjecture
that the Mori cone is polyhedral and generated by rational curves. Our main
result is that the conjecture holds iff it holds for $g=0$. More precisely,
there is a natural finite map $r: \vmgn 0. 2g+n. \to \mgn$ whose image is the
locus $\rgn$ of curves with all components rational. Any 1-strata either lies
in $\rgn$ or is numerically equivalent to a family $E$ of elliptic tails and we
show that a divisor $D$ is nef iff $D \cdot E \geq 0$ and $r^*(D)$ is nef. We
also give results on contractions (i.e. morphisms with connected fibers to
projective varieties) of $\mgn$ for $g \geq 1$ showing that any fibration
factors through a tautological one (given by forgetting points) and that the
exceptional locus of any birational contraction is contained in the boundary.
Finally, by more ad-hoc arguments, we prove the nefness of certain special
classes.

</DOC>
<DOC>
<DOCNO> 72198 </DOCNO>
The anomalous gamma -> pi^+ pi^0 pi^- form factor and the light-quark


  The gamma -> 3 pi form factor was calculated in a simple-minded constituent
model with a constant quark mass parameter, as well as in the Schwinger-Dyson
approach. The comparison of these and various other theoretical results on this
anomalous process, as well as the scarce already available data (hopefully to
be supplemented by more accurate CEBAF data), seem to favor Schwinger-Dyson
modeling which would yield relatively small low-momentum values of the
constituent (dynamically dressed) quark mass function.

</DOC>
<DOC>
<DOCNO> 100507 </DOCNO>
Algebra of Principal Fibre Bundles, and Connections


  We put together some of the efforts by several people of making aspects of
fibre bundle theory into algebra. The initiator of these efforts was Charles
Ehresmann, who put the notion of groupoid and groupoid action in the focus of
fibre bundle theory in general, and in connection theory in particular.

</DOC>
<DOC>
<DOCNO> 121108 </DOCNO>
Three-Dimensional Modeling of the Deflagration Stage of a Type Ia


  The paper describes a physical model and numerical algorithm for modeling
Type Ia supernova (SNIa) explosions in three dimensions and presents first
results of modeling a deflagration explosion in a nonrotating,
Chandrasekhar-mass carbon-oxygen (CO) white dwarf. Simulations show that the
turbulent flame speed grows exponentially, reaches approximately 30% of the
speed of sound, and then declines as the large-scale turbulence is frozen by
expansion. The freezing of turbulent motions appears to be a crucial physical
mechanism regulating the rate of deflagration in SNIa. The energy of the
explosion is comparable to that of a typical SNIa. However, the presence of the
outer layer of unburned CO and the formation of intermediate mass elements and
pockets of unburned CO near the center pose problems for the modeling of SNIa
spectra. Delayed detonation is a way to alleviate these problems and to produce
consistent spectra.

</DOC>
<DOC>
<DOCNO> 121969 </DOCNO>
AGN and Starburst Galaxies Seen through Radio Surveys


  The emergence of a new population of radio galaxies at mJy and sub-mJy levels
is responsible for the change in the slope of the radio source counts. This
population seems to include both star forming galaxies and classical
(AGN-powered) radio sources, but the relative importance of the two classes is
still debated. We present results from the ATESP radio survey and its optical
follow-up and show that the fraction of starburst galaxies changes from ~15% at
fluxes >1 mJy to >50% at lower fluxes.

</DOC>
<DOC>
<DOCNO> 117127 </DOCNO>
MOE11 Emittance Growth from the Thermalization of Space-Charge


  Beams injected into a linear focusing channel  typically have some degree of
space-charge  nonuniformity. In general, injected particle distributions with 
systematic charge nonuniformities are not  equilibria of the focusing channel
and launch a  broad spectrum of collective modes. These  modes can phase-mix
and have nonlinear wave-wave  interactions which, at high space-charge
intensities, results  in a relaxation to a more thermal-like distribution
characterized  by a uniform density profile. This thermalization can  transfer
self-field energy from the initial  space-charge nonuniformity to the local
particle  temperature, thereby increasing beam phase space  area (emittance
growth). In this paper, we  employ a simple kinetic model of a continuous
focusing  channel and build on previous work that applied system  energy and
charge  conservation quantify emittance growth associated with  the collective
thermalization of an initial azimuthally  symmetric, rms matched beam with a
radial density profile  that is hollowed or peaked. This emittance growth is
shown to  be surprisingly modest even for high beam intensities with 
significant radial structure in the initial density profile.

</DOC>
<DOC>
<DOCNO> 12597 </DOCNO>
Generation of arbitrary Dicke states in spinor Bose-Einstein condensates


  We demonstrate that the combination of two-body collisions and applied Rabi
pulses makes it possible to prepare arbitrary Dicke (spin) states as well as
maximally entangled states by appropriate sequencing of external fields.

</DOC>
<DOC>
<DOCNO> 101486 </DOCNO>
Endomorphisms of hypersurfaces and other manifolds


  We prove that a smooth hypersurface of degree >2 and dimension >1 admits no
endomorphism of degree >1 (for hyperquadrics this is due to Paranjape and
Srinivas). We then collect some general results on endomorphisms of projective
manifolds; we prove in particular that ramified endomorphisms occur only on
varieties of negative Kodaira dimension, and we classify those Del Pezzo
surfaces which admit such endomorphism.

</DOC>
<DOC>
<DOCNO> 8680 </DOCNO>
Probing spin-charge separation using spin transport


  Pedagogical discussions are given on what constitutes a signature of
spin-charge separation. A proposal is outlined to probe spin-charge separation
in the normal state of the high $T_c$ cuprates using spin transport.
Specifically, the proposal is to compare the temperature dependences of the
spin resistivity and electrical resistivity: Spin-charge separation will be
manifested in the different temperature dependences of these two resistivities.
We also estimate the spin diffusion length and spin relaxation time scales, and
we argue that it should be experimentally feasible to measure the spin
transport properties in the cuprates using the spin-injection technique. The
on-going spin-injection experiments in the cuprates and related theoretical
issues are also discussed.

</DOC>
<DOC>
<DOCNO> 150487 </DOCNO>
The tale of gravitational sphaleron


  Type I string theory can be dimensionally reduced on group manifolds. The
compactification on $S^3\times S^3$ leads to the N=4 gauged SU(2)$\times$SU(2)
supergravity in four dimensions, which admits the BPS monopole type non-Abelian
vacuum. The reduction on $S^3\times AdS_3$ gives the Euclidean N=4 gauged
SU(2)$\times$SU(1,1) supergravity admitting a globally regular supersymmetric
non-Abelian background. The latter can be analytically continued to the
Lorentzian sector, which gives the regular, unstable particle-like
configuration known as gravitational sphaleron. When lifted to D=10, the
Euclidean vacuum describes a deformation of the D1--D5 brane system.

</DOC>
<DOC>
<DOCNO> 70135 </DOCNO>
On the production of a lepton pair in the collision of ultrarelativistic


  Explicit formulas which describe muon pair production in reaction $\gamma\nu
\to \mu^+ \mu^- \nu$ through neutrino magnetic moment are obtained and used to
derive in the leading approximation cross section of muon pair production in
$\nu N$-scattering due to neutrino magnetic moment. This cross section appears
to be proportional to $\log^4 E_{\nu}$. Comparison with experimental data on
tridents production provides an upper bound $\mu_{\nu_{\mu}} < 4*10^{-8}
\mu_B$, which is approximately two orders of magnitude weaker than that from
$\nu_{\mu}e$ elastic scattering data.

</DOC>
<DOC>
<DOCNO> 178637 </DOCNO>
NN-->NNpi from the effective field theory point of view: short comings


  Based on a counting scheme for the application of chiral perturbation theory
to pion production in NN collisions p-wave production is studied. It is
demonstrated that, contrary to the s-wave production where loops enter at too
low an order to allow the scheme predictive power, there are certain p-wave
observables where parameter free predictions are possible. These predictions
are consistent with experimental data. We show that the investigation of
charged pion production yields a constraint on a contribution to the
three-nucleon force with a spin-isospin structure that could resolve the $A_y$
puzzle in $nd$ scattering.

</DOC>
<DOC>
<DOCNO> 40202 </DOCNO>
Study of inclusive D_S^((*)+/-) production in B decays and measurement


  Electron-positron annihilation data collected by the BABAR detector near the
Y(4S) resonance are used to study the inclusive decay of B mesons to D_S^(+/-)
and D_S^(*+/-) mesons, where the D_S^(+/-) is reconstructed using the decay
D_S^(+/-) --> phi pi^(+/-). The production fraction of inclusive D_S^((*)+/-)
and the corresponding momentum spectra have been determined. The exclusive
decays B^0 --> D^(*-)D_S^((*)+) are observed with a partial reconstruction
technique which uses the soft pion from the D^(*+/-) decay in association with
the reconstructed D_S^((*)+/-). The beam energy constraint is used to determine
the missing mass recoiling against the D_S^(+/-) system, showing a clear signal
for this process. From the observed rates, preliminary results for the
corresponding branching fractions have been obtained.

</DOC>
<DOC>
<DOCNO> 71262 </DOCNO>
Strings in Meson and Baryon Physics


  The relativistic string with massive ends (the meson model) and four various
string baryon models: q-qq, q-q-q, Y and $\Delta$ are considered. In
particular, the rotational motions for all these systems are applied to
describing the leading Regge trajectories, and also the classical dynamics
beyond the usual rectilinear string rotations is studied. For the string meson
model the two types of quasirotational motions (disturbances of the planar
uniform rotations) are obtained. They are oscillatory motions in the form of
stationary waves in the rotational plane and in the orthogonal direction. The
analysis of the stability problem for the rotational motions for all mentioned
string configurations shows that these motions for the Y and q-q-q models are
unstable on the classical level.

</DOC>
<DOC>
<DOCNO> 9501 </DOCNO>
Theory for Electron-Doped Cuprate Superconductors: d-wave symmetry order


  Using as a model the Hubbard Hamiltonian we determine various basic
properties of electron-doped cuprate superconductors like
${Nd}_{2-x}{Ce}_{x}{CuO}_{4}$ and ${Pr}_{2-x}{Ce}_{x}{CuO}_{4}$ for a
spin-fluctuation-induced pairing mechanism. Most importantly we find a narrow
range of superconductivity and like for hole-doped cuprates $d_{x^{2}-y^{2}}$ -
symmetry for the superconducting order parameter. The superconducting
transition temperatures $T_{c}(x)$ for various electron doping concentrations
$x$ are calculated to be much smaller than for hole-doped cuprates due to the
different Fermi surface and a flat band well below the Fermi level. Lattice
disorder may sensitively distort the symmetry $d_{x^{2}-y^{2}}$ via
electron-phonon interaction.

</DOC>
<DOC>
<DOCNO> 101174 </DOCNO>
On self-similar singular solutions of the complex Ginzburg-Landau


  We address the open problem of existence of singularities for the complex
Ginzburg-Landau equation. Using a combination of rigourous results and
numerical computations, we describe a countable family of self-similar
singularities. Our analysis includes the super-critical non-linear Schroedinger
equation as a special case, and most of the described singularities are new
even in that situation. We also consider the problem of stability of these
singularities.

</DOC>
<DOC>
<DOCNO> 118847 </DOCNO>
Multiparameter estimation with the Pseudo-C_l method


  We apply the Pseudo-C_l formalism to obtain an unbiased, approximate method
for efficient simultaneous estimation of several cosmological parameters from
large, almost full-sky cosmic microwave background data sets.

</DOC>
<DOC>
<DOCNO> 174496 </DOCNO>
Creation and decay of eta-mesic nuclei


  First experimental results on photoproduction of eta-mesic nuclei are
analyzed. In an experiment performed at the 1 GeV electron synchrotron of the
Lebedev Physical Institute, correlated pi+n pairs arising from the reaction
gamma + 12C -> N + eta(A-1) -> N + pi+ + n + (A-2) and flying transversely to
the photon beam have been observed. When the photon energy exceeds the
eta-meson production threshold, a distribution of the pi+n pairs over their
total energy is found to have a peak in the subthreshold region of the
internal-conversion process eta p -> pi+ n which signals about formation of
eta-mesic nuclei.

</DOC>
<DOC>
<DOCNO> 118489 </DOCNO>
Determination of Masses and Radii of the Massive Eclipsing Binary System


  We present a V light curve of the eclipsing binary system HV 2543 (Sk-67 117)
in the Large Magellanic Cloud based on CCD images acquired between the years
1995 and 1998. We have analysed this light curve and published radial velocity
data, finding that this system is semidetached, with the secondary (less
massive and less luminous component) filling its Roche lobe. From our analysis
with the Wilson-Devinney code, we estimated the following masses and radii for
the components of HV 2543: M1=25.63 +- 0.7, R1=15.54 +- 0.4, M2=15.63 +- 1.0
and R2=13.99 +- 0.4, in solar units. On the basis of B and V photometry of the
field stars, we found that HV 2543 is member of an OB association, perhaps
related to which the massive binary system Sk-67 105 belongs.

</DOC>
<DOC>
<DOCNO> 68419 </DOCNO>
A new twist to preheating


  Metric perturbations typically strengthen field resonances during preheating.
In contrast we present a model in which the super-Hubble field resonances are
completely {\em suppressed} when metric perturbations are included. The model
is the nonminimal Fakir-Unruh scenario which is exactly solvable in the
long-wavelength limit when metric perturbations are included, but exhibits
exponential growth of super-Hubble modes in their absence. This gravitationally
enhanced integrability is exceptional, both for its rarity and for the power
with which it illustrates the importance of including metric perturbations in
consistent studies of preheating. We conjecture a no-go result - there exists
no {\em single-field} model with growth of cosmologically-relevant metric
perturbations during preheating.

</DOC>
<DOC>
<DOCNO> 70578 </DOCNO>
A Solution of the Generation Puzzle from Yang-Mills Duality


  A solution to the generation puzzle based on a nonabelian generalization of
electric-magnetic duality is briefly reviewed. It predicts 3 and only 3
generations of fermions and explains the hierarchical mass spectrum as well as
the main features in both the quark and lepton mixing matrices. A calculation
to leading perturbative order already gives reasonable values to about half of
the Standard Model parameters.

</DOC>
<DOC>
<DOCNO> 10167 </DOCNO>
InAs-AlSb quantum wells in tilted magnetic fields


  InAs-AlSb quantum wells are investigated by transport experiments in magnetic
fields tilted with respect to the sample normal. Using the coincidence method
we find for magnetic fields up to 28 T that the spin splitting can be as large
as 5 times the Landau splitting. We find a value of the g-factor of about 13.
For small even-integer filling factors the corresponding minima in the
Shubnikov-de Haas oscillations cannot be tuned into maxima for arbitrary tilt
angles. This indicates the anti-crossing of neighboring Landau and spin levels.
Furthermore we find for particular tilt angles a crossover from even-integer
dominated Shubnikov-de Haas minima to odd-integer minima as a function of
magnetic field.

</DOC>
<DOC>
<DOCNO> 101943 </DOCNO>
Ramification of local fields with imperfect residue fields


  Classically the ramification filtration of the Galois group of a complete
discrete valuation field is defined in the case where the residue field is
perfect. In this paper, we define without any assumption on the residue field,
two ramification filtrations and study some of their properties.

</DOC>
<DOC>
<DOCNO> 117020 </DOCNO>
On the Possibility of Local SR Construction


  The violation of the invariance of the speed of light in Special Relativity
has been made. The version of the theory (LSR) has been constructed in which
the possibility of the superluminal motions are permitted. Some predictions of
this theory are available for experimental check, for example, the measurements
of aberration angles, the observation of distinctions between the redshifts in
radio and optical ranges of a spectrum, the detection of superluminal objects
in astrophysics and in time-flight experiments.

</DOC>
<DOC>
<DOCNO> 10175 </DOCNO>
Fredholm determinant representation for the partition function of the


  The six-vertex model with domain wall boundary conditions is considered. A
Fredholm determinant representation for the partition function of the model is
obtained. The kernel of the corrtesponding integral operator depends on
Laguerre polynomials.

</DOC>
<DOC>
<DOCNO> 70636 </DOCNO>
Small-x Structure Functions and QCD Pomeron


  The recent progress in color BFKL-Regge phenomenology of small-x DIS on
nucleons, pions and photons is reviewed

</DOC>
<DOC>
<DOCNO> 151995 </DOCNO>
Non-Abelian Stokes theorem and quark confinement in QCD


  To understand the Abelian dominance and magnetic monopole dominance in
low-energy QCD, we rewrite the non-Abelian Wilson loop into the form which is
written in terms of its Abelian components or the 't Hooft-Polyakov tensor
describing the magnetic monopole. This is peformed by making use of a version
of non-Abelian Stokes theorem. We propose a modified version of the maximal
Abelian (MA) gauge. By adopting the modified MA gauge in QCD, we show that the
off-diagonal gluons and Faddeev-Popov ghosts acquire their masses through the
ghost--anti-ghost condensation due to four ghost interaction coming from the
gauge-fixing term of the modified MA gauge. The asymptotic freedom of the
original non-Abelian gauge theory is preserved in this derivation.

</DOC>
<DOC>
<DOCNO> 11132 </DOCNO>
Field-induced long-range order in the S=1 antiferromagnetic chain


  The quasi-one dimensional S=1 antiferromagnet in magnetic field H is
investigated with the exact diagonalization of finite chains and the mean field
approximation for the interchain interaction. In the presence of the single-ion
anisotropy D, the full phase diagram in the $HT$ plane is presented for H
\parallel D and H \perp D. The shape of the field-induced long-range ordered
phase is revealed to be quite different between the two cases, as observed in
the recent experiment of NDMAP. The estimated ratio of the interchain and
intrachain couplings of NDMAP (J'/J ~ 10^{-3}) is consistent with the neutron
scattering measurement.

</DOC>
<DOC>
<DOCNO> 152613 </DOCNO>
On the Vacuum Structure of Type II String Compactifications on


  We discuss the vacuum structure of type IIA/B Calabi-Yau string
compactifications to four dimensions in the presence of n-form H-fluxes. These
will lift the vacuum degeneracy in the Calabi-Yau moduli space, and for generic
points in the moduli space, N=2 supersymmetry will be broken. However, for
certain `aligned' choices of the H-flux vector, supersymmetric ground states
are possible at the degeneration points of the Calabi-Yau geometry. We will
investigate in detail the H-flux induced superpotential and the corresponding
scalar potential at several degeneration points, such as the Calabi-Yau large
volume limit, the conifold loci, the Seiberg-Witten points, the strong coupling
point and the conformal points. Some emphasis is given to the question whether
partial supersymmetry breaking can be realized at those points. We also relate
the H-flux induced superpotential to the formalism of gauged N=2 supergravity.
Finally we point out the analogies between the Calabi-Yau vacuum structure due
to H-fluxes and the attractor formalism of N=2 black holes.

</DOC>
<DOC>
<DOCNO> 121116 </DOCNO>
Physical Diagnostics from a Narrow Fe-Kalpha Emission Line Detected by


  We report the detection of a narrow Fe-K emission line in the Seyfert 1
galaxy NGC 5548 with the Chandra High-Energy Transmission Gratings. In the
galaxy frame we measure a center energy of 6.40 \pm 0.03 keV, a FWHM of 4515
(+3525,-2645) km/s, and an equivalent width of 133 (+62,-54) eV. The line
energy is consistent with an origin in cold, neutral matter, but ionization
states up to ~Fe XVIII are not ruled out. Assuming Keplerian motion, the
velocity width is consistent with the line being produced in the outer
optical/UV broad-line region (BLR) at about a light-month from the central
X-ray source. We cannot rule out some contribution to the Fe-K line from a
putative, parsec-scale obscuring torus. The continuum intensity during the
Chandra observation was a factor ~2 less than typical historical levels. If the
X-ray continuum was > than a factor 2 higher in the recent past before the
Chandra observation and the narrow Fe-K line intensity had not yet responded,
then the predicted line equivalent width and intensity for an origin in the BLR
is within the 90% measurement errors. Retroactive spectral fitting of archival
ASCA data shows evidence that the narrow Fe-K has a variable intensity. It will
be important to measure the non-disk component of the Fe-K line in other AGN to
obtain a more complete understanding of the total Fe-K line emission.
Measurement of the narrow-line parameters provides powerful diagnostics of
conditions beyond the accretion disk and is necessary to properly deconvolve
the broad, relativistic Fe-K line.

</DOC>
<DOC>
<DOCNO> 13514 </DOCNO>
Rotating Bose gas with hard-core repulsion in a quasi-2D harmonic trap:


  We consider a gas of N(=6, 10, 15) Bose particles with hard-core repulsion,
contained in a quasi-2D harmonic trap and subjected to an overall angular
velocity $\Omega$ about the z-axis. Exact diagonalization of the $n\times n$
many-body Hamiltonian matrix in given subspaces of the total (quantized)
angular momentum L$_{z}$, with $n\sim 10^{5}$(e.g. for L$_{z}$=N=15, n =240782)
was carried out using Davidson's algorithm. The many-body variational ground
state wavefunction, as also the corresponding energy and the reduced
one-particle density-matrix were calculated. With the usual identification of
$\Omega$ as the Lagrange multiplier associated with L$_{z}$ for a rotating
system, the $L_{z}-\Omega$ phase diagram (or the stability line) was determined
that gave a number of critical angular velocities $\Omega_{{\bf c}i},
i=1,2,3,... ,$ at which the ground state angular momentum and the associated
condensate fraction undergo abrupt jumps.
  A number of (total) angular momentum states were found to be stable at
successively higher critical angular velocities $\Omega_{{\bf c}i}, \
i=1,2,3,...$ for a given N. For $L_{z}>N$, the condensate was strongly
depleted. The critical $\Omega_{{\bf c}i}$ values, however, decreased with
increasing interaction strength as well as the particle number, and were
systematically greater than the non-variational Yrast-state values for the
single vortex state with L$_{z}$ =N. We have also observed that the condensate
fraction for the single vortex state (as also for the higher vortex states) did
not change significantly even as the 2-body interaction strength was varied
over several $(\sim 4)$ orders of magnitude in the moderately to the weakly
interacting regime. 

</DOC>
<DOC>
<DOCNO> 120064 </DOCNO>
The structure and kinematics of AGN with ionization cones


  Results of 2D spectral observations for 4 Sy galaxies with ionization cones
are presented. Images in the [OIII] line, velocity fields of the ionized gas,
stellar velocity and velocity dispersion fields were obtained at the SAO RAS 6m
telescope. Non-circular gas motions and Z-shaped emission filaments could be
explained as helical waves located in the ionization cone. This waves are
generated by the hydrodynamical instability due to the velocity break between
galactic ISM and outflowing matter from the AGN engine. The axis of cone lies
close to the direction of a nuclear mini bar.

</DOC>
<DOC>
<DOCNO> 71033 </DOCNO>
Anarchy and Hierarchy


  We advocate a new approach to study models of fermion masses and mixings,
namely anarchy proposed in hep-ph/9911341. In this approach, we scan the O(1)
coefficients randomly. We argue that this is the correct approach when the
fundamental theory is sufficiently complicated. Assuming there is no physical
distinction among three generations of neutrinos, the probability distributions
in MNS mixing angles can be predicted independent of the choice of the measure.
This is because the mixing angles are distributed according to the Haar measure
of the Lie groups whose elements diagonalize the mass matrices. The
near-maximal mixings, as observed in the atmospheric neutrino data and as
required in the LMA solution to the solar neutrino problem, are highly
probable. A small hierarchy between the Delta m^2 for the atmospheric and the
solar neutrinos is obtained very easily; the complex seesaw case gives a
hierarchy of a factor of 20 as the most probable one, even though this
conclusion is more measure-dependent. U_{e3} has to be just below the current
limit from the CHOOZ experiment. The CP-violating parameter sin delta is
preferred to be maximal. We present a simple SU(5)-like extension of anarchy to
the charged-lepton and quark sectors which works well phenomenologically.

</DOC>
<DOC>
<DOCNO> 69781 </DOCNO>
Transport phenomena in stochastic magnetic mirrors


  Parallel thermal conduction along stochastic magnetic field lines may be
reduced because the heat conducting electrons become trapped and detrapped
between regions of strong magnetic field (magnetic mirrors). The problem
reduces to a simple but realistic model for diffusion of mono-energetic
electrons based on the fact that when there is a reduction of diffusion, it is
controlled by a subset of the mirrors, the principle mirrors. The diffusion
reduction can be considered as equivalent to an enhancement of the pitch angle
scattering rate. Therefore, in deriving the collision integral, we modify the
pitch angle scattering term. We take into account the full perturbed
electron-electron collision integral, as well as the electron-proton collision
term. Finally, we obtain the four plasma transport coefficients and the
effective thermal conductivity. We express them as reductions from the
classical values. We present these reductions as functions of the ratio of the
magnetic field decorrelation length to the electron mean free path at the
thermal speed $V_T=\sqrt{2kT/m_e}$. We briefly discuss an application of our
results to clusters of galaxies.
  Key words: magnetic fields: conduction --- magnetic fields: diffusion ---
methods: analytical --- plasmas

</DOC>
<DOC>
<DOCNO> 80877 </DOCNO>
Numerical studies of confinement in the lattice Landau gauge


  Critical conjectures on confinement in the Landau gauge is numerically tested
in focus to Gribov copy effects. One of the subjects is of the Kugo-Ojima
confinement criterion and the other is of various viewpoints in the
Gribov-Zwanziger theory. We use the smearing gauge as a reference gauge free of
Gribov copy, and performed three types of simulations, log U, U-linear and log
U in the smearing gauge. It is found that Gribov copy effect on the Kugo-Ojima
parameter is small. log U and U-linear simulations yield only global scale
factor difference in gluon propagator and in ghost propagator, and about 10%
difference in Kugo-Ojima parameter. The horizon function defined by Zwanziger
is evaluated in three types of gauge field and compared. All data show the
negative horizon function as expected.

</DOC>
<DOC>
<DOCNO> 121114 </DOCNO>
Secondary CMB Anisotropies from Cosmological Reionization


  We use numerical simulation of cosmological reionization to calculate the
secondary CMB anisotropies in a representative flat low density cosmological
model. We show that the kinetic Sunyaev-Zel'dovich effect (scattering off of
moving electrons in the ionized intergalactic medium) is dominated by the
nonlinear hydrodynamic and gravitational evolution of the density and velocity
fields, rather than the detailed distribution of the ionization fraction
(``patchy reionization'') on all angular scales. Combining our results with the
recent calculation of secondary CMB anisotropies by Springel et al., we are
able to accurately predict the power spectrum of the kinetic SZ effect on
almost all angular scales.

</DOC>
<DOC>
<DOCNO> 118018 </DOCNO>
Non-uniform reionization by galaxies and its effect on the cosmic


  We present predictions for the reionization of the intergalactic medium by
stars in high-redshift galaxies. We calculate ionizing luminosities of
galaxies, including the effects of absorption by interstellar gas and dust on
the escape fraction, in order to calculate the filling factor of ionized
hydrogen in the IGM. For a $\Lambda{\rm CDM}$ cosmology and a physical
calculation of the escape fraction, we find that the hydrogen in the IGM will
be reionized at redshift z=6.1 if the IGM has uniform density, but only by
z=4.5 if the IGM is clumped. We combine our model with an N-body simulation of
the distribution of dark matter in the universe in order to calculate the
secondary temperature anisotropies induced in the cosmic microwave background
(CMB) by scattering off free electrons. The models predict a spectrum of
secondary anisotropies covering a broad range of angular scales, with
fractional temperature fluctuations $\sim 10^{-7}-10^{-6}$ on arcminute scales.
The amplitude depends somewhat on the geometry of reionization, with models in
which the regions of highest gas density are reionized first giving larger CMB
fluctuations than the case where galaxies ionize surrounding spherical regions,
and models where low density regions reionize first giving the smallest
fluctuations. Measurement of these anisotropies can therefore put important
constraints on the reionization process, in particular, the redshift evolution
of the filling factor, and should be a primary objective of a next generation
submillimeter telescope such as the Atacama Large Millimeter Array. (abrdiged)

</DOC>
<DOC>
<DOCNO> 122066 </DOCNO>
The Best Brown Dwarf Yet?: A Companion to the Hyades Eclipsing Binary


  We have carried out an analysis of about 160 eclipse timings spanning over 30
years of the Hyades eclipsing binary V471 Tauri that shows a long-term
quasi-sinusoidal modulation of its observed eclipse arrival times. The O-Cs
have been analyzed for the ``light-time'' effect that arises from the
gravitational influence of a tertiary companion. The presence of a third body
causes the relative distance of the eclipsing pair to the Earth to change as it
orbits the barycenter of the triple system. The result of the analysis of the
eclipse times yields a light-time semi-amplitude of 137.2+/-12.0 s, an orbital
period of P_3 = 30.5+/-1.6 yr and an eccentricity of e_3 = 0.31+/-0.04. The
mass of the tertiary component is M_3 sin i_3 = 0.0393+/-0.0038 Mo when a total
mass of 1.61+/-0.06 Mo for V471 Tau is adopted. For orbital inclinations i_3 >
35 deg, the mass of the third body would be below the stable hydrogen burning
limit of M = 0.07 Mo and it thus would be a brown dwarf. In the next several
years (near maximum elongation), it should be feasible to obtain IR images and
spectra of V471 Tau C that, when combined with the known mass, age, distance,
and [Fe/H], will serve as a benchmark for understanding the physical properties
and evolution of brown dwarfs.

</DOC>
<DOC>
<DOCNO> 12126 </DOCNO>
Dynamics of spin correlations in the spin-1/2 isotropic XY chain in a


  Dynamic xx spin pair correlation functions for the isotropic spin-1/2 XY
chain are calculated numerically for long open chains in the presence of a
transverse magnetic field at finite temperature. As an application we discuss
the temperature dependence of the spin-spin relaxation time in PrCl_3.

</DOC>
<DOC>
<DOCNO> 119113 </DOCNO>
Galaxy surface photometry


  We describe galaxy surface photometry based on fitting ellipses to the
isophotes of the galaxies. Example galaxies with different isophotal shapes are
used to illustrate the process, including how the deviations from elliptical
isophotes are quantified using Fourier expansions. We show how the definitions
of the Fourier coefficients employed by different authors are linked. As
examples of applications of surface photometry we discuss the determination of
the relative disk luminosities and the inclinations for E and S0 galaxies. We
also describe the color-magnitude and color-color relations. When using both
near-infrared and optical photometry, the age-metallicity degeneracy may be
broken. Finally we discuss the Fundamental Plane where surface photometry is
combined with spectroscopy. It is shown how the FP can be used as a sensitive
tool to study galaxy evolution.

</DOC>
<DOC>
<DOCNO> 71269 </DOCNO>
Techniques for solving bound state problems


  We have used different methods to obtain the bound states of a Hamiltonian of
a relativistic two scalar particle system in a local potential. The potentials
we are interested in are binding and confining potentials, that are associated
with particle exchange. The issues we concentrate on when comparing the
different methods are ease of numerical implementation, accuracy and stability.
To check our codes we have made use of several potentials for which the bound
states are known in the nonrelativistic situation. Finally we calculate the
bound states for the Yukawa potential in the relativistic situation and look at
the collapse of the wave functions in this situation.

</DOC>
<DOC>
<DOCNO> 118255 </DOCNO>
Highly polarized structures in the near-nuclear regions of Cygnus A:


  We present near-IR imaging polarimetry observations of the nucleus of Cygnus
A, taken with the NICMOS camera of the HST at a wavelength of 2.0 microns.These
maps reveal a highly collimated region of polarized emission straddling the
nucleus and extending to a radius of 1.2 arcseconds. Remarkably, this feature
coincides with one, but only one, limb of the edge-brightened bicone structure
seen in the total intensity image. The high degree (P_k ~ 25%) and orientation
of the extended polarization feature are consistent with a scattering origin.
Most plausibly, the detection of polarization along only one limb of the bicone
is a consequence of intrinsic anisotropy of the near-IR continuum within the
radiation cones, with the direction of maximum intensity of the near-IR
radiation field significantly displaced from the direction of the radio axis.
The unresolved nuclear core source is also highly polarized (P_k > 28%), with a
position angle close to the perpendicular to the radio axis. Given that this
high degree of nuclear polarization can only be explained in terms of dichroic
extinction if the dichroic mechanism is unusually efficient in Cygnus A, it is
more likely that the nuclear polarization is due to the scattering of nuclear
light in an unresolved scattering region close to the AGN. In this case, the
flux of the core source in the K-band is dominated by scattered rather than
transmitted quasar light, and previous extinction estimates based on K-band
photometry of the core substantially underestimate the true nuclear extinction.

</DOC>
<DOC>
<DOCNO> 9029 </DOCNO>
Reorientational relaxation of a linear probe molecule in a simple glassy


  Within the mode-coupling theory (MCT) for the evolution of structural
relaxation in glass-forming liquids, correlation functions and susceptibility
spectra are calculated characterizing the rotational dynamics of a top-down
symmetric dumbbell molecule, consisting of two fused hard spheres immersed in a
hard-sphere system. It is found that for sufficiently large dumbbell
elongations, the dynamics of the probe molecule follows the same universal
glass-transition scenario as known from the MCT results of simple liquids. The
$\alpha$-relaxation process of the angular-index-j=1 response is stronger,
slower and less stretched than the one for j=2, in qualitative agreement with
results found by dielectric-loss and depolarized-light-scattering spectroscopy
for some supercooled liquids. For sufficiently small elongations, the
reorientational relaxation occurs via large-angle flips, and the standard
scenario for the glass-transition dynamics is modified for odd-j responses due
to precursor phenomena of a nearby type-A MCT transition. In this case, a major
part of the relaxation outside the transient regime is described qualitatively
by the $\beta$-relaxation scaling laws, while the $\alpha$-relaxation scaling
law is strongly disturbed.

</DOC>
<DOC>
<DOCNO> 84970 </DOCNO>
Three-Dimensional Billiards with Time Machine


  Self-collision of a non-relativistic classical point-like body, or particle,
in the spacetime containing closed time-like curves (time-machine spacetime) is
considered. A point-like body (particle) is an idealization of a small ideal
elastic billiard ball. The known model of a time machine is used containing a
wormhole leading to the past. If the body enters one of the mouths of the
wormhole, it emerges from another mouth in an earlier time so that both the
particle and its "incarnation" coexist during some time and may collide. Such
self-collisions are considered in the case when the size of the body is much
less than the radius of the mouth, and the latter is much less than the
distance between the mouths. Three-dimensional configurations of trajectories
with a self-collision are presented. Their dynamics is investigated in detail.
Configurations corresponding to multiple wormhole traversals are discussed. It
is shown that, for each world line describing self-collision of a particle,
dynamically equivalent configurations exist in which the particle collides not
with itself but with an identical particle having a closed trajectory (Jinnee
of Time Machine).

</DOC>
<DOC>
<DOCNO> 119465 </DOCNO>
ROSAT PSPC detection of soft X-ray absorption in GB 1428+4217: The most


  We report on a ROSAT PSPC observation of the highly-luminous z = 4.72
radio-loud quasar GB 1428+4217 obtained between 1998 December 11 and 17, the
final days of the ROSAT satellite. The low-energy sensitivity of the PSPC
detector was employed to constrain the intrinsic X-ray absorption of the
currently most distant X-ray detected object. Here we present the detection of
significant soft X-ray absorption towards GB 1428+4217, making the absorbing
material the most distant matter yet probed with X-ray spectroscopy. X-ray
variability by 25+-8 per cent is detected on a timescale of 6500 s in the rest
frame. The X-ray variation requires an unusually high radiative efficiency of
at least 4.2, further supporting the blazar nature of the source.

</DOC>
<DOC>
<DOCNO> 85211 </DOCNO>
Complete null data for a black hole collision


  We present an algorithm for calculating the complete data on an event horizon
which constitute the necessary input for characteristic evolution of the
exterior spacetime. We apply this algorithm to study the intrinsic and
extrinsic geometry of a binary black hole event horizon, constructing a
sequence of binary black hole event horizons which approaches a single
Schwarzschild black hole horizon as a limiting case. The linear perturbation of
the Schwarzschild horizon provides global insight into the close limit for
binary black holes, in which the individual holes have joined in the infinite
past. In general there is a division of the horizon into interior and exterior
regions, analogous to the division of the Schwarzschild horizon by the r=2M
bifurcation sphere. In passing from the perturbative to the strongly nonlinear
regime there is a transition in which the individual black holes persist in the
exterior portion of the horizon. The algorithm is intended to provide the data
sets for production of a catalog of nonlinear post-merger wave forms using the
PITT null code.

</DOC>
<DOC>
<DOCNO> 7836 </DOCNO>
Non-Gaussian velocity distributions in excited granular matter in the


  The velocity distribution of spheres rolling on a slightly tilted rectangular
two dimensional surface is obtained by high speed imaging. The particles are
excited by periodic forcing of one of the side walls. Our data suggests that
strongly non-Gaussian velocity distributions can occur in dilute granular
materials even in the absence of significant density correlations or
clustering. When the surface on which the particles roll is tilted further to
introduce stronger gravitation, the collision frequency with the driving wall
increases and the velocity component distributions approach Gaussian
distributions of different widths.

</DOC>
<DOC>
<DOCNO> 169969 </DOCNO>
Optomechanical tailoring of quantum fluctuations


  We propose the use of feedback mechanism to control the level of quantum
noise in a radiation field emerging from a pendular Fabry-Perot cavity. It is
based on the possibility to perform quantum nondemolition measurements by means
of optomechanical coupling.

</DOC>
<DOC>
<DOCNO> 12083 </DOCNO>
Scale-dependence of Elastic Constants in the Decoupled Lamellar Phase of


  We analyse the effect of thermal fluctuations on the elastic constants of the
decoupled lamellar phase of tethered, crystalline membranes. Using a
momentum-shell renormalization group technique, we show that the smectic-A
-like compressional elastic constant, the in-plane Lam\'{e} coefficients, and
the cross-coupling elastic constant vanish as (\ln q)^{- a} whereas the bend
elastic constant diverges as (\ln q)^{b}, with a, b > 0, as the wavenumber q
tends to zero. The exponents a and b satisfy the relation a + 3b = 2.

</DOC>
<DOC>
<DOCNO> 178817 </DOCNO>
Quantum Group SU_{q}(2) and Pairing in Nuclei


  A scheme for treating the pairing of nucleons in terms of generators of
Quantum Group SU_{q}(2) is presented. The possible applications to nucleon
pairs in a single orbit, multishell case, pairing vibrations and
superconducting nuclei are discussed. The formalism for performing BCS
calculations with q-deformed nucleon pairs is constructed and the role played
by deformation parameter q analyzed in the context of nucleons in a single
orbit and for Sn Isotopes.

</DOC>
<DOC>
<DOCNO> 101715 </DOCNO>
Infinite-dimensional Grassmann-Banach algebras


  A short review on infinite-dimensional Grassmann-Banach algebras (IDGBA) is
presented. Starting with the simplest IDGBA over $K = {\bf R}$ with $l_1$-norm
(suggested by A. Rogers), we define a more general IDGBA over complete normed
field $K$ with $l_1$-norm and set of generators of arbitrary power. Any
$l_1$-type IDGBA may be obtained by action of Grassmann-Banach functor of
projective type on certain $l_1$-space. In non-Archimedean case there exists
another possibility for constructing of IDGBA using the Grassmann-Banach
functor of injective type.

</DOC>
<DOC>
<DOCNO> 72085 </DOCNO>
Infrared and ultraviolet cutoffs of quantum field theory


  Quantum gravity arguments and the entropy bound for effective field theories
proposed in PRL 82, 4971 (1999) lead to consider two correlated scales which
parametrize departures from relativistic quantum field theory at low and high
energies. A simple estimate of their possible phenomenological implications
leads to identify a scale of around 100 TeV as an upper limit on the domain of
validity of a quantum field theory description of Nature. This fact agrees with
recent theoretical developments in large extra dimensions. Phenomenological
consequences in the beta-decay spectrum and cosmic ray physics associated to
possible Lorentz invariance violations induced by the infrared scale are
discussed. It is also suggested that this scale might produce new unexpected
effects at the quantum level.

</DOC>
<DOC>
<DOCNO> 68015 </DOCNO>
MeV-scale Reheating Temperature and Thermalization of Neutrino


  The late-time entropy production by the massive particle decay induces the
various cosmological effects in the early epoch and modify the standard
scenario. We investigate the thermalization process of the neutrinos after the
entropy production by solving the Boltzmann equations numerically. We find that
if the large entropy are produced at t $\sim$ 1 sec, the neutrinos are not
thermalized very well and do not have the perfect Fermi-Dirac distribution.
Then the freeze-out value of the neutron to proton ratio is altered
considerably and the produced light elements, especially He4, are drastically
changed. Comparing with the observational light element abundances, we find
that $T_R$ < 0.7 MeV is excluded at 95 % C.L. We also study the case in which
the massive particle has a decay mode into hadrons. Then we find that $T_R$
should be a little higher, i.e. $T_R$ > 2.5 MeV - 4 MeV, for the hadronic
branching ratio $B_h = 10^{-2} - 1$. Possible influence of late-time entropy
production on the large scale structure formation and temperature anisotropies
of cosmic microwave background is studied. It is expected that the future
satellite experiments (MAP and PLANCK) to measure anisotropies of cosmic
microwave background radiation temperature can detect the vestige of the
late-time entropy production as a modification of the effective number of the
neutrino species $N_{\nu}^{\rm eff}$.

</DOC>
<DOC>
<DOCNO> 99901 </DOCNO>
Representations of SU(1,1) in Non-commutative Space Generated by the


  SU(1,1) is considered as the automorphism group of the Heisenberg algebra H.
The basis in the Hilbert space K of functions on H on which the irreducible
representations of the group are realized is explicitly constructed. The
addition theorems are derived.

</DOC>
<DOC>
<DOCNO> 170287 </DOCNO>
Early times in tunneling


  Exact analytical solutions of the time-dependent Schr\"odinger equation with
the initial condition of an incident cutoff wave are used to investigate the
traversal time for tunneling. The probability density starts from a vanishing
value along the tunneling and transmitted regions of the potential. At the
barrier width it exhibits, at early times, a distribution of traversal times
that typically has a peak $\tau_p$ and a width $\Delta \tau$. Numerical results
for other tunneling times, as the phase-delay time, fall within $\Delta \tau$.
The B\"uttiker traversal time is the closest to $\tau_p$. Our results resemble
calculations based on Feynman paths if its noisy behaviour is ignored.

</DOC>
<DOC>
<DOCNO> 84414 </DOCNO>
Chaos around the superposition of a monopole and a thick disk


  We extend recent investigations on the integrability of oblique orbits of
test particles under the gravitational field corresponding to the superposition
of an infinitesimally thin disk and a monopole to the more realistic case, for
astrophysical purposes, of a thick disk. Exhaustive numerical analyses were
performed and the robustness of the recent results is confirmed. We also found
that, for smooth distributions of matter, the disk thickness can attenuate the
chaotic behavior of the bounded oblique orbits. Perturbations leading to the
breakdown of the reflection symmetry about the equatorial plane, nevertheless,
may enhance significantly the chaotic behavior, in agreement with recent
studies on oblate models.

</DOC>
<DOC>
<DOCNO> 69778 </DOCNO>
Discrete scalar fields and general relativity


  The physical meaning, the properties and the consequences of a discrete
scalar field are discussed; limits for a continuous mathematical description of
fundamental physics is a natural outcome of discrete fields with discrete
interactions. The discrete scalar field is ultimately the gravitational field
of general relativity, necessarily, and there is no place for any other
fundamental scalar field, in this context.

</DOC>
<DOC>
<DOCNO> 170595 </DOCNO>
Basic concepts in quantum computation


  Section headings: 1 Qubits, gates and networks 2 Quantum arithmetic and
function evaluations 3 Algorithms and their complexity 4 From interferometers
to computers 5 The first quantum algorithms 6 Quantum search 7 Optimal phase
estimation 8 Periodicity and quantum factoring 9 Cryptography 10 Conditional
quantum dynamics 11 Decoherence and recoherence 12 Concluding remarks

</DOC>
<DOC>
<DOCNO> 170743 </DOCNO>
Observation of decoherence with a movable mirror


  Recently it has been proposed to use parity as a measure of the mechanism
behind decoherence or the transformation from quantum to classical. Here, we
show that the proposed experiment is more feasible than previously thought, as
even an initial thermal state would exhibit the hypothesized symmetry breaking.

</DOC>
<DOC>
<DOCNO> 151792 </DOCNO>
A Note on D-Branes of Odd Codimensions from Noncommutative Tachyons


  On a noncommutative space of rank-1, we construct a codimension-one soliton
explicitly and, in the context of noncommutative bosonic open string field
theory, identify it with the D24-brane. We compute the tension of the proposed
D24-brane, yielding an exact value and show that it is related to the tension
of the codimension two D23-brane by the string T-duality. This resolves an
apparent puzzle posed by the result of Harvey, Kraus, Larsen and Martinec and
proves that the T-duality is a gauge symmetry; in particular, at strong
noncommutativity, it is part of the U(oo) gauge symmetry on the worldvolume. We
also apply the result to non-BPS D-branes in superstring theories and argue
that the codimension-one soliton gives rise to new descent relation among the
non-BPS D-branes in Type IIA and Type IIB string theories via T-duality.

</DOC>
<DOC>
<DOCNO> 10473 </DOCNO>
Gapless Haldane phase in realistic systems


  This preprint has been merged with cond-mat/0005361

</DOC>
<DOC>
<DOCNO> 10345 </DOCNO>
Anomalous dephasing of bosonic excitons interacting with phonons in the


  The dephasing and relaxation kinetics of bosonic excitons interacting with a
thermal bath of acoustic phonons is studied after coherent pulse excitation.
The kinetics of the induced excitonic polarization is calculated within
Markovian equations both for subcritical and supercritical excitation with
respect to a Bose-Einstein condensation (BEC). For excited densities n below
the critical density n_c, an exponential polarization decay is obtained, which
is characterized by a dephasing rate G=1/T_2. This dephasing rate due to phonon
scattering shows a pronounced exciton-density dependence in the vicinity of the
phase transition. It is well described by the power law G (n-n_c)^2 that can be
understood by linearization of the equations around the equilibrium solution.
Above the critical density we get a non-exponential relaxation to the final
condensate value p^0 with |p(t)|-|p^0| ~1/t that holds for all densities.
Furthermore we include the full self-consistent Hartree-Fock-Bogoliubov (HFB)
terms due to the exciton-exciton interaction and the kinetics of the anomalous
functions F_k= <a_k a_{-k}>. The collision terms are analyzed and an
approximation is used which is consistent with the existence of BEC. The
inclusion of the coherent x-x interaction does not change the dephasing laws.
The anomalous function F_k exhibits a clear threshold behaviour at the critical
density.

</DOC>
<DOC>
<DOCNO> 116606 </DOCNO>
Experiments on the generation of long wavelength edge radiation along


  Generation of long wavelength edge radiation along directions nearly
coincident with the axes of straight sections of storage rings and synchrotrons
is discussed. The removal of destructive interference from the superimposed
edge radiation patterns of a straight section on the synchrotron "Pakhra" has
been observed experimentally.

</DOC>
<DOC>
<DOCNO> 70966 </DOCNO>
A very brief review of Bose-Einstein correlations


  The GGLP approach to Bose-Einstein correlations, a hydrodynamic model and a
string model are briefly reviewed. The implications of the two models for the
Bose-Einstein correlations among the decay products of a pair of W bosons are
presented.

</DOC>
<DOC>
<DOCNO> 12700 </DOCNO>
Brownian motors: noisy transport far from equilibrium


  Transport phenomena in spatially periodic systems far from thermal
equilibrium are considered. The main emphasize is put on directed transport in
so-called Brownian motors (ratchets), i.e. a dissipative dynamics in the
presence of thermal noise and some prototypical perturbation that drives the
system out of equilibrium without introducing a priori an obvious bias into one
or the other direction of motion. Symmetry conditions for the appearance (or
not) of directed current, its inversion upon variation of certain parameters,
and quantitative theoretical predictions for specific models are reviewed as
well as a wide variety of experimental realizations and biological
applications, especially the modeling of molecular motors. Extensions include
quantum mechanical and collective effects, Hamiltonian ratchets, the influence
of spatial disorder, and diffusive transport.

</DOC>
<DOC>
<DOCNO> 120433 </DOCNO>
Local Axisymmetric Instability Criterion in the Thin, Rotating,


  Purely gravitational perturbations are considered in a thin rotating disk
composed of several gas and stellar components. The dispersion relation for the
axisymmetric density waves propagating through the disk is found and the
criterion for the local axisymmetric stability of the whole system is
formulated. In the appropriate limit of two-component gas we confirm the
findings of Jog & Solomon (1984) and extend consideration to the case when one
component is collisionless. Gravitational stability of the Galactic disk in the
Solar neighborhood based on the multicomponent instability condition is
explored using recent measurements of the stellar composition and kinematics in
the local Galactic disk obtained by Hipparcos satellite.

</DOC>
<DOC>
<DOCNO> 120247 </DOCNO>
The multiphase nature of the intra-cluster medium of some clusters of


  The discovery of EUV and soft X-ray excess emission in clusters of galaxies
(the cluster soft-excess phenomenon) challenged the notion of the hot ($\sim
10^{7-8}$ K) gas as the only dominant thermal component of the intracluster
medium (ICM). The spatial analysis of ROSAT PSPC 1/4 keV images presented here
reveals compelling evidence for substantial amounts of cold gas (HI) in the ICM
of the Coma and Virgo clusters. This finding bolsters the original
interpretation of the soft excess as emission from a `warm' ($\sim 10^6$ K) gas
and points to the scenario of a multiphase ICM where the hot component
co-exists with gases at sub-Virial temperatures (the `warm' and `cold' phases).

</DOC>
<DOC>
<DOCNO> 9494 </DOCNO>
Numerical studies of the extended two-chain model of friction


  We investigate numerically a simple microscopic model to describe wearless
dry friction between atomically flat contact interfaces without thermal
fluctuations (T=0K). The analysis of the incommensurate ground state shows a
breaking of analyticity when the amplitude $\epsilon$ of the Lennard-Jones
interaction between the both harmonic chains increased beyond a critical value
$\epsilon_c$. By the introduction of a suitable order parameter and using a
finite size scaling we could show that the breaking of analyticity is a second
order phase transition. This transition is often called Aubry transition. By
applying of an uniform external force $F^{ex}$ we have determined the critical
force of static friction $F_c$ above a sliding motion occurs.

</DOC>
<DOC>
<DOCNO> 120041 </DOCNO>
Extragalactic 2-10 keV source counts from a fluctuation analysis of deep


  We present an analysis of the spatial fluctuations of the 2-10 keV Cosmic
X-ray Background (CXB) as measured from 22 high galactic latitude (|b| > 25
deg) fields observed with the MECS instrument on-board BeppoSAX. This technique
allowed us to probe extragalactic source counts a factor 3-4 fainter than is
possible with direct measurements of pointlike sources in MECS deep fields. The
slope of the 2-10 keV logN-logS relationship is found to be still close to the
``Euclidean'' one (gamma = 1.5) down to our flux limit of 1.5 10^-14 erg cm^-2
s^-1, where the contribution of discrete sources to the 2-10 keV CXB amounts to
40-50%. Source counts derived from the analysis presented in this letter are in
very good agreement both with those directly measured with ASCA and BeppoSAX
deep surveys at bright fluxes and with a first estimation of the 2-10 keV
Chandra logN-logS at fainter fluxes.

</DOC>
<DOC>
<DOCNO> 99371 </DOCNO>
Acoustics of the Indian Drum


  This article investigates as to how the Indian Drums are able to produce
harmonics. In particular, it looks at the density distribution on an Indian
Drum, the Tabla, and shows that it is the form of the density distribution that
results in harmonics.

</DOC>
<DOC>
<DOCNO> 70238 </DOCNO>
A Strategy for the Analysis of Semi-Inclusive Deep Inelastic Scattering


  We present a strategy for the systematic extraction of a vast amount of
detailed information on polarized parton densities and fragmentation functions
from semi-inclusive deep inelastic scattering l+N -> l+h+X, in both LO and NLO
QCD. A method is suggested for estimating the errors involved in the much
simpler, and therefore much more attractive,
 LO analysis. The approach is based upon a novel interplay with data from
inclusive DIS and from e+e- -> hX, and leads to a much simplified form of the
NLO expressions. No assumptions are made about the equality of any parton
densities and the only symmetries utilised are charge conjugation invariance
and isotopic spin invariance of strong interactions.

</DOC>
<DOC>
<DOCNO> 120616 </DOCNO>
Robustly Unstable Eigenmodes of the Magnetoshearing Instability in


  The stability of nonaxisymmetric perturbations in differentially rotating
astrophysical accretion disks is analyzed by fully incorporating the properties
of shear flows. We verify the presence of discrete unstable eigenmodes with
complex and pure imaginary eigenvalues, without any artificial disk edge
boundaries, unlike Ogilvie & Pringle(1996)'s claim. By developing the
mathematical theory of a non-self-adjoint system, we investigate the nonlocal
behavior of eigenmodes in the vicinity of Alfven singularities at
omega_D=omega_A, where omega_D is the Doppler-shifted wave frequency and
omega_A=k_// v_A is the Alfven frequency. The structure of the spectrum of
discrete eigenmodes is discussed and the magnetic field and wavenumber
dependence of the growth rate are obtained. Exponentially growing modes are
present even in a region where the local dispersion relation theory claims to
have stable eigenvalues. The velocity field created by an eigenmode is
obtained, which explains the anomalous angular momentum transport in the
nonlinear stage of this stability.

</DOC>
<DOC>
<DOCNO> 8219 </DOCNO>
The effect of strain on the adsorption of CO on Pd(100)


  We study how the binding energy, the vibrational frequencies and the
adsorption isotherm of CO on Pd(100) are modified when the solid is subject to
uniform strain. The parameters controlling the thermodynamics of adsorption
(the adsorption energy, the vibrational frequencies of the adsorbed molecules
and the interaction energy between the molecules) have been calculated by using
density functional theory. These parameters are then used in a grand canonical
Monte Carlo simulation that determines the CO coverage when the surface is in
thermodynamic equilibrium with a CO gas, at a specified pressure and
temperature. We find that this is substantially affected by the strain. Our
results, along with those obtained by others, suggest that the development of
"elastochemistry", a study of the change in the chemical properties of a
surface when subjected to strain, will lead to interesting and measurable
results. It also suggests that differences in chemical activity between
clusters on a support and clusters in gas phase may be partly due to the strain
induced when a cluster is placed on the support.

</DOC>
<DOC>
<DOCNO> 72115 </DOCNO>
Supergravity models of Quintessence and Supersymmetry breaking


  The issue of Supersymmetry breaking in the context of Supergravity models of
Quintessence is discussed.

</DOC>
<DOC>
<DOCNO> 67875 </DOCNO>
Cosmological evolution in compactified Horava-Witten theory induced by


  The combined Einstein equations and scalar equation of motion in the
Horava-Witten scenario of the strongly coupled heterotic string compactified on
a Calabi-Yau manifold are solved in the presence of additional matter densities
on the branes. We take into account the universal Calabi-Yau modulus phi with
potentials in the 5-d bulk and on the 3-branes, and allow for an arbitrary
coupling of the additional matter to phi and an arbitrary equation of state. No
ad hoc stabilization of the five dimensional radius is assumed. The matter
densities are assumed to be small compared to the potential for phi on the
branes; in this approximation we find solutions in the bulk which are exact in
y and t. Depending on the coupling of the matter to phi and its equation of
state, various solutions for the metric on the branes and in the 5-d bulk are
obtained: Solutions corresponding to a ``rolling radius'', and solutions with a
static 5-d radius, which reproduce the standard cosmological evolution.

</DOC>
<DOC>
<DOCNO> 150964 </DOCNO>
Cosmological Constant and Fermi-Bose Degeneracy


  We study some cases in D=4 and in infinite-volume high dimensional theories
when unbroken supersymmetry in the vacuum cannot guarantee Fermi-Bose
degeneracy among excited states. In 4D we consider an example in which both
supersymmetry and $R$ symmetry are unbroken in the vacuum, and the cosmological
constant vanishes. However, theory admits solitons that do not allow existence
of conserved supercharges. These objects are magnetically charged global
monopoles which in some respect behave as point-like particles, but create a
solid angle deficit which eliminates asymptotically covariantly constant
spinors and lifts Fermi-Bose degeneracy of the spectrum. The idea is that in
some "dual" description monopoles with global topological number and gauge
magnetic charge may be replaced by electrically chaged particles with global
Noether charges, e.g., such as baryon number. Alternatively theories with
infinite volume extra dimensions may support unbroken bulk supersymmetry
without Fermi-Bose degeneracy in the brane spectrum. We suggest a scenario in
which brane is a source similar to a global monopole embedded in 3 infinite
extra dimensions. Brane produces a deficit angle at infinity and may localize a
meta-stable 4D graviton. Although bulk cosmological constant is zero, conserved
supercharges can not be defined on such a background.

</DOC>
<DOC>
<DOCNO> 67803 </DOCNO>
Comment on "Calculation of the Quarkonium Spectrum and m(b), m(c) to


  A recent determination of the mass of the b quark, based exclusively on
quantum chromodynamics (by avoiding strictly to introduce any phenomenological
interaction potential of nonperturbative origin), may be improved by allowing
for a merely numerical solution of the corresponding eigenvalue problem.

</DOC>
<DOC>
<DOCNO> 170243 </DOCNO>
The Schmidt Measure as a Tool for Quantifying Multi-Particle


  We present a measure of quantum entanglement which is capable of quantifying
the degree of entanglement of a multi-partite quantum system. This measure,
which is based on a generalization of the Schmidt rank of a pure state, is
defined on the full state space and is shown to be an entanglement monotone,
that is, it cannot increase under local quantum operations with classical
communication and under mixing. For a large class of mixed states this measure
of entanglement can be calculated exactly, and it provides a detailed
classification of mixed states.

</DOC>
<DOC>
<DOCNO> 101742 </DOCNO>
On the number of return words in infinite words with complexity 2n+1


  In this article, we count the number of return words in some infinite words
with complexity 2n+1. We also consider some infinite words given by codings of
rotation and interval exchange transformations on k intervals. We prove that
the number of return words over a given word w for these infinite words is
exactly k.

</DOC>
<DOC>
<DOCNO> 118246 </DOCNO>
The hard X-ray properties of the Seyfert nucleus in NGC 1365


  We present BeppoSAX observations of the Seyfert 1.8 galaxy NGC1365 in the
0.1--100 keV range. The source was 6 times brighter than during an ASCA
observation 3 years earlier. The 4--10 keV flux is highly variable during the
BeppoSAX observation, while the soft (0.1-4 keV) emission is constant within
the errors. Both a cold and a warm reflector and a cold absorber are required
to explain the observed spectrum. The comparison between ASCA and BeppoSAX
spectra strongly suggests that the circumnuclear material has a more complex
structure than a simple homogeneous torus, with quite different absorbing gas
columns along different lines of sight. A broad iron K_alpha line is also
present in the spectrum, with the peak energy significantly redshifted. This
can be explained by means of a relativistic disk line model. Alternatively, a
warm absorption Fe line system with N_H ~ 10^23 cm^(-2) could account for the
observed line profile.

</DOC>
<DOC>
<DOCNO> 120355 </DOCNO>
Prediction of Astrophysical Reaction Rates: Methods, Data Needs, and


  The majority of nuclear reactions in astrophysics involve unstable nuclei
which are not fully accessible by experiments yet. Therefore, there is high
demand for reliable predictions of cross sections and reaction rates by
theoretical means. The majority of reactions can be treated in the framework of
the statistical model (Hauser-Feshbach). The global parametrizations of the
nuclear properties needed for predictions far off stability probe our
understanding of the strong force and take it to its limit.
  The sensitivity of astrophysical scenarios to nuclear inputs is illustrated
in the framework of a detailed nucleosynthesis study in type II supernovae.
Abundances resulting from calculations in the same explosion model with two
different sets of reaction rates are compared. Key reactions and required
nuclear information are identified.

</DOC>
<DOC>
<DOCNO> 10655 </DOCNO>
Elastic properties of model porous ceramics


  The finite element method (FEM) is used to study the influence of porosity
and pore shape on the elastic properties of model porous ceramics. The Young's
modulus of each model was found to be practically independent of the solid
Poisson's ratio. At a sufficiently high porosity, the Poisson's ratio of the
porous models converged to a fixed value independent of the solid Poisson's
ratio. The Young's modulus of the models is in good agreement with experimental
data. We provide simple formulae which can be used to predict the elastic
properties of ceramics, and allow the accurate interpretation of empirical
property-porosity relations in terms of pore shape and structure.

</DOC>
<DOC>
<DOCNO> 151062 </DOCNO>
Gravity localization with a domain wall junction in six dimensions


  We study gravity localization in the context of a six-dimensional gravity
model coupled with complex scalar fields. With a supergravity-motivated scalar
potential, we show that the domain wall junction solutions localize a
four-dimensional massless graviton under an assumption on the wall profile. We
find that unlike the global supersymmetric model, contributions to the junction
tension cancel locally with gravitational contributions. The wall tension
vanishes due to the metric suppression.

</DOC>
<DOC>
<DOCNO> 178800 </DOCNO>
Coulomb Excitation of Double Giant Dipole Resonances


  We implement the Brink-Axel hypothesis for the excitation of the double giant
dipole resonance (DGDR): The background states which couple to the one-phonon
giant dipole resonance are themselves capable of dipole absorption. These
states (and the ones which couple to the two-phonon resonance) are described in
terms of the Gaussian Orthogonal Ensemble of random matrices. We use
second-order time-dependent perturbation theory and calculate analytically the
ensemble-averaged cross section for excitation of the DGDR. Numerical
calculations illuminate the mechanism and the dependence of the cross section
on the various parameters of the theory, and are specifically performed for the
reaction $^{208}$Pb + $^{208}$Pb at a projectile energy of 640 MeV/nucleon. We
show that the contribution of the background states to the excitation of the
DGDR is significant. We find that the width of the DGDR, the energy-integrated
cross section and the ratio of this quantity over the energy-integrated cross
section for the single giant dipole resonance, all agree with experiment within
experimental errors. We compare our approach with that of Carlson {\it et al.}
who have used a similar physical picture.

</DOC>
<DOC>
<DOCNO> 178912 </DOCNO>
Observing compact quark matter droplets in relativistic nuclear


  Compactness is introduced as a new method to search for the onset of the
quark matter transition in relativistic heavy ion collisions. That transition
supposedly leads to stronger compression and higher compactness of the source
in coordinate space. That effect could be observed via pion interferometry. We
propose to measure the compactness of the source in the appropriate principal
axis frame of the compactness tensor in coordinate space.

</DOC>
<DOC>
<DOCNO> 84088 </DOCNO>
Scalar-Tensor Gravity in Two 3-brane System


  We derive the low-energy effective action of four-dimensional gravity in the
Randall-Sundrum scenario in which two 3-branes of opposite tension reside in a
five-dimensional spacetime. The dimensional reduction with the Ansatz for the
radion field by Charmousis et al., which solves five-dimensional linearized
field equations, results in a class of scalar-tensor gravity theories. In the
limit of vanishing radion fluctuations, the effective action reduces to the
Brans-Dicke gravity in accord with the results of Garriga and Tanaka:
Brans-Dicke gravity with the corresponding Brans-Dicke parameter $0< \omega <
\infty$ (for positive tension brane) and $-3/2< \omega <0$ (for negative
tension brane). In general the gravity induced a brane belongs to a class of
scalar-tensor gravity with the Brans-Dicke parameter which is a function of the
interval and the radion. In particular, gravity on a positive tension brane
contains an attractor mechanism toward the Einstein gravity.

</DOC>
<DOC>
<DOCNO> 84949 </DOCNO>
Properties of general relativistic, irrotational binary neutron stars in


  We investigate close binary neutron stars in quasiequilibrium states in a
general relativistic framework. We assume conformal flatness for the spatial
metric and irrotational velocity field for the neutron stars. We adopt the
polytropic equation of state. The computation is performed for the polytropic
index n(=0.5, 0.66667, 0.8, 1, 1.25), and compactness of neutron stars
M/R(=0.03 - 0.3). Results of this paper are as follows. (i) The sequences of
the irrotational binary are always terminated at an innermost orbit where a
cusp (inner Lagrange point)appears at the inner edges of the stellar surface.
The binaries with cusps are found to be dynamically unstable for n=0.5 and
stable for n > 0.8 irrespective of M/R < 0.2. For n=0.66667, the stability
changes depending on M/R. (ii) The gravitational wave frequency at the
innermost orbit turns out to be between 800 and 1500 Hz for realistic
compactness 0.14 < M/R < 0.2. (iii) The ISCO for n=0.5 appears to be determined
by a hydrodynamic instability for M/R < 0.2. We derive fitting formulae for the
relation between the orbital angular velocity at the ISCO and the compactness
to clarify it. (iv) The maximum density of neutron stars in binary systems
slightly decreases with decreasing the orbital separation and hence they are
stable against individual radial collapse during the inspiral. (v) q =
J_tot/M_ADM^2 at the innermost orbits is always less than unity for M/R > 0.13
irrespective of n, which indicates that the realistic binary neutron stars
satisfy a necessary condition (q<1) for formation of a black hole before the
merger. (vi) The specific angular momentum of any mass element in irrotational
binary neutron stars at the innermost orbit appears to be too small to form a
disk around black holes formed after the merger.

</DOC>
<DOC>
<DOCNO> 120945 </DOCNO>
Cosmology with Varying Constants


  I motivate and discuss some recent work on theories with varying constants,
and consider some possible observational consequences and tests. Particular
emphasis is given to models which can (almost) exactly mimic the predictions of
standard inflationary models.

</DOC>
<DOC>
<DOCNO> 9492 </DOCNO>
The Haldane bosonisation scheme and metallic states of interacting


  We consider the Haldane bosonisation scheme in d spatial dimensions as
applied to a realistic model of interacting fermions in d=2 and unequivocally
demonstrate failure of this scheme in d > 1, specifically in d=2. In addition
to tracing back this failure to its origin, we show that {\sl nothing} as
regards the true metallic state of the model under consideration is known with
any degree of certainty.

</DOC>
<DOC>
<DOCNO> 99859 </DOCNO>
Quantum currents in the Coset Space SU(2)/U(1)


  We propose a rational quantum deformed nonlocal currents in the homogenous
space $SU(2)_k/U(1)$, and in terms of it and a free boson field a
representation for the Drinfeld currents of Yangian double at a general level
$k=c$ is obtained. In the classical limit $\hbar \to 0$, the quantum nonlocal
currents become $SU(2)_k$ parafermion, and the realization of Yangian double
becomes the parafermion realization of $SU(2)_k$ current algebra.

</DOC>
<DOC>
<DOCNO> 150330 </DOCNO>
On the Non-perturbative Properties of the Yang-Mills Vacuum and the


  The non-perturbative part of the vacuum energy density for static
configuration in pure SU(2) Y-M theory is described. The vacuum state is
constructed.

</DOC>
<DOC>
<DOCNO> 71207 </DOCNO>
Azimuthal and Single Spin Asimmetries in Deep Inelastic Scattering


  Azimuthal and single spin asymmetries play a crucial role in the study of the
spin structure of hadrons in terms of their elementary constituents. Exploiting
them to uncover information over subtle distribution and fragmentation
functions, which cannot easily be accessed in other ways, is what this talk is
about.

</DOC>
<DOC>
<DOCNO> 70011 </DOCNO>
On Measurement of Helicity Parameters in Top Quark Decay


  To enable an evaluation of future measurements of the helicity parameters for
" t --> W b " decay in regard to " T_FS violation", this paper considers the
effects of an additional pure-imaginary coupling, (i g/2 Lambda) or (i g),
associated with a specific, single additional Lorentz structure, i = S, P, S +
P, ... Sizable " T_FS violation" signatures can occur for low-effective mass
scales (< 320 GeV), but in most cases can be more simply excluded by 10%
precision measurement of the probabilities P(W_L) and P(b_L). Signatures for
excluding the presence of " T_FS violation" associated with the two dynamical
phase-type ambiguities are investigated.

</DOC>
<DOC>
<DOCNO> 178652 </DOCNO>
The Liquid-Gas Phase Transitions in a Multicomponent Nuclear System with


  The liquid-gas phase transition is studied in a multi-component nuclear
system using a local Skyrme interaction with Coulomb and surface effects. Some
features are qualitatively the same as the results of Muller and Serot which
uses relativistic mean field without Coulomb and surface effects. Surface
tension brings the coexistance binodal surface to lower pressure. The Coulomb
interaction makes the binodal surface smaller and cause another pair of binodal
points at low pressure and large proton fraction with less protons in liquid
phase and more protons in gas phase.

</DOC>
<DOC>
<DOCNO> 119803 </DOCNO>
Energetic particle acceleration in a 3D magnetic field reconnection


  The role of MHD turbulence in the cosmic ray acceleration process in a volume
with a reconnecting magnetic field is studied by means of Monte Carlo
simulations. We performed modelling of proton acceleration with the 3D analytic
model of stationary reconnection of Craig et al. (1995) providing the
unperturbed background conditions. Perturbations of particle trajectories due
to a turbulent magnetic field component were simulated using small-amplitude
pitch-angle momentum scattering, enabling modelling of both small and large
amplitude turbulence in a wide wave vector range. Within the approach, no
second-order Fermi acceleration process is allowed. Comparison of the
acceleration process in models involving particle trajectory perturbations to
the unperturbed one reveals that the turbulence can substantially increase the
acceleration efficiency, enabling much higher final particle energies and flat
particle spectra.

</DOC>
<DOC>
<DOCNO> 12021 </DOCNO>
Anti-Kondo resonance in transport through a quantum wire with a


  An interacting quantum dot side-coupled to a perfect quantum wire is studied.
Transport through the quantum wire is investigated by using an exact sum rule
and the slave-boson mean field treatment. It is shown that the Kondo effect
provides a suppression of the transmission due to the destructive interference
of the ballistic channel and the Kondo channel. At finite temperatures,
anti-resonance behavior is found as a function of the quantum dot level
position, which is interpreted as a crossover from the high temperature Kondo
phase to the low temperature charge fluctuation phase.

</DOC>
<DOC>
<DOCNO> 117048 </DOCNO>
Soliton Generation and Picosecond Collapse in Solid-State Lasers with


  Based on self - consistent field theory we study a soliton generation in cw
solid-state lasers with semiconductor saturable absorber. Various soliton
destabilizations, i.e. the switch from femtosecond to picosecond generation
(''picosecond collapse''), an automodulation regime, breakdown of soliton
generation and hysteresis behavior, are predicted.

</DOC>
<DOC>
<DOCNO> 11460 </DOCNO>
Dynamical Behaviour in the Nonlinear Rheology of Surfactant Solutions


  Several surfactant molecules self-assemble in solution to form long, flexible
wormlike micelles which get entangled with each other, leading to viscoelastic
gel phases. We discuss our recent work on the rheology of such a gel formed in
the dilute aqueous solutions of a surfactant CTAT. In the linear rheology
regime, the storage modulus $G^{\prime}(\omega)$ and loss modulus
$G^{\prime\prime}(\omega)$ have been measured over a wide frequency range. In
the nonlinear regime, the shear stress $\sigma$ shows a plateau as a function
of the shear rate $\dot\gamma$ above a certain cutoff shear rate
$\dot\gamma_c$. Under controlled shear rate conditions in the plateau regime,
the shear stress and the first normal stress difference show oscillatory
time-dependence. The analysis of the measured time series of shear stress and
normal stress has been done using several methods incorporating state space
reconstruction by embedding of time delay vectors.The analysis shows the
existence of a finite correlation dimension and a positive Lyapunov exponent,
unambiguously implying that the dynamics of the observed mechanical instability
can be described by that of a dynamical system with a strange attractor of
dimension varying from 2.4 to 2.9.

</DOC>
<DOC>
<DOCNO> 117197 </DOCNO>
What Future Expects Humanity After the Demographic Transition Time?


  The variant of phenomenological theory of humankind future existence after
time of demographic transition based on treating the time of demographic
transition as a point of phase transition and taking into account an appearing
of the new phase of mankind is proposed. The theory based on physical
phenomenological theories of phase transitions and classical equations for
system predatory-preys for two phases of mankind, take into account assumption
about a multifractal nature of the set of number of people in temporal axis and
contains control parameters. The theory includes scenario of destroying of
existent now human population by new phase of humanity and scenario of old and
new phases co-existence. In particular cases when the new phase of mankind is
absent the equations of theory may be formulated as equations of Kapitza,
Foerster, Hoerner, Kobelev and Nugaeva, Johansen and Sornette phenomenological
theories of growth of mankind.

</DOC>
<DOC>
<DOCNO> 120280 </DOCNO>
Looking into Pulsar Magnetospheres


  Diffractive and refractive magnetospheric scintillations may allow a direct
testing of the plasma inside the light cylinder. Unusual electrodynamics of the
strongly magnetized electron-positron plasma allow separation of the
magnetospheric and interstellar scattering.
  The most distinctive feature of the magnetospheric scintillations is their
independence on frequency. Diffractive scattering due to small scale
inhomogeneities produce a scattering angle that may be as large as 0.1 radians,
and a typical decorrelation time of $10^{-8}$ seconds.
  Refractive scattering due to large scale inhomogeneities is also possible,
with a typical angle of $10^{-3}$ radians and a correlation time of the order
of $10^{-4}$ seconds. Some of the magnetospheric propagation effects may have
already been observed.

</DOC>
<DOC>
<DOCNO> 9430 </DOCNO>
Quasi-Particle Bound States around Impurities in d-wave Superconductors


  Zn and Ni impurities in the hole-doped high-temperature superconductors are
known to have strong effects on thermodynamic and transport properties. A
recent scanning tunneling microscope study of Zn-doped Bi2212 (Pan et al.,
Nature 403, 746 (2000)) has provided high-resolution images of the local
density of states around non-magnetic impurities in d-wave superconductors.
These pictures contain detailed information about the spinor wave functions
u(r) and v(r) of bound states with energy E_0 \sim Delta/30, centered at the
Zn-sites. We show that this type of wave function follows from the solutions of
the Bogoliubov-de Gennes equations for d-wave superconductors.

</DOC>
<DOC>
<DOCNO> 116979 </DOCNO>
Concept of Staged Approach for International Fusion Materials


  The intense neutron source for development of fusion materials planned by
international collaboration makes a new step to clarify the technical issues
for realizing the 40 MeV, 250 mA deuteron beam facility. The baseline concept
employs two identical 125 mA linac modules whose beams are combined at the
flowing lithium target. Recent work for reducing the cost loading concerns the
staged deployment of the full irradiation capability in three steps. The
Japanese activity about the design and development study about IFMIF
accelerator in this year is presented and the schedule of next several years is
overviewed.

</DOC>
<DOC>
<DOCNO> 9157 </DOCNO>
Damping of condensate collective modes due to equilibration with the


  We consider the damping of condensate collective modes at finite temperatures
arising from lack of equilibrium between the condensate and the non-condensate
atoms, an effect that is ignored in the usual discussion of the collisionless
region. As a first approximation, we ignore the dynamics of the thermal cloud.
Our calculations should be applicable to collective modes of the condensate
which are oscillating out-of-phase with the thermal cloud. We obtain a
generalized Stringari equation of motion for the condensate at finite
temperatures, which includes a damping term associated with the fact that the
condensate is not in diffusive equilibrium with the static thermal cloud. This
inter-component collisional damping of the condensate modes is comparable in
magnitude to the Landau damping considered in the recent literature.

</DOC>
<DOC>
<DOCNO> 151453 </DOCNO>
A superspace approach to branes and supergravity


  Recent developments in string and M theory rely heavily on supersymmetry
suggesting that a revival of superspace techniques in ten and eleven dimensions
may be advantageous. Here we discuss three topics of current interest where
superspace is already playing an important role and where an improved
understanding of superspace might provide additional insight into the issues
involved.

</DOC>
<DOC>
<DOCNO> 118176 </DOCNO>
The Broad Line Region in Active Galactic Nuclei


  We review constraints on models of the broad line region that are imposed by
observations of the emission lines in Active Galactic Nuclei. Comparison of
high and low ionization lines in sources with FWHM Hbeta < 4000 km/s points
toward low ionization line emission produced in a flattened geometry (the
accretion disk?) with an associated high ionization wind. It remains unclear
whether these results can be extended to all radio quiet AGN and particularly
to radio loud AGN.

</DOC>
<DOC>
<DOCNO> 116960 </DOCNO>
Collective Acceleration of Ions by Means of Plasmoids in RF Wells of


  The proposed linear accelerator ("scanator") consists of a terawatt table-top
laser and a set of passive elements - beam splitters, dispersion elements for
stretching of the laser pulse and chirping of the splitted beams, and
dispersion elements for angle scanning of crossed frequency-modulated laser
beams. Ions are trapped and accelerated in RF wells by the electron component
of plasmoids in the intersection zone of the scanning laser beams.
Computational studies give encouraging results. A proof-of-principle experiment
on the base of a table-top laser is outlined.

</DOC>
<DOC>
<DOCNO> 118959 </DOCNO>
Vertical motions in the disk of NGC 5668 as seen with optical


  We have observed the nearly face-on spiral galaxy NGC 5668 with the TAURUS II
Fabry-Perot interferometer at the William Herschel Telescope using the
$H\alpha$ line to study the kinematics of the ionized gas. From the extracted
data cube we construct intensity, velocity and velocity dispersion maps. We
calculate the rotation curve in the innermost 2 arcmin and we use the residual
velocity field to look for regions with important vertical motions. By
comparing the geometry of these regions in the residual velocity field with the
geometry in the intensity and velocity dispersion maps we are able to select
some regions which are very likely to be shells or chimneys in the disk. The
geometry and size of these regions are very similar to the shells or chimneys
detected in other galaxies by different means. Moreover, it is worth noting
than this galaxy has been reported to have a population of neutral hydrogen
high velocity clouds (Schulman et al. 1996) which, according to these
observations, could have been originated by chimneys similar to those reported
in this paper.

</DOC>
<DOC>
<DOCNO> 101260 </DOCNO>
Mean curvature 1 surfaces in hyperbolic 3-space with low total curvature


  A complete surface of constant mean curvature 1 (CMC-1) in hyperbolic 3-space
with constant curvature -1 has two natural notions of "total curvature"--- one
is the total absolute curvature which is the integral over the surface of the
absolute value of the Gaussian curvature, and the other is the dual total
absolute curvature which is the total absolute curvature of the dual CMC-1
surface. In this paper, we completely classify CMC-1 surfaces with dual total
absolute curvature at most 4\pi. Moreover, we give new examples and partially
classify CMC-1 surfaces with dual total absolute curvature at most 8\pi.

</DOC>
<DOC>
<DOCNO> 120327 </DOCNO>
HST/NICMOS observations of the host galaxies of powerful radio sources:


  We present near-infrared J and K band imaging of a sample of powerful radio
source host galaxies with the Hubble Space Telescope NICMOS2 camera. These
sources have been selected on their double lobed radio structure, and include a
wide range of projected radio source sizes. The largest projected linear sizes
range from the compact Gigahertz Peaked Spectrum (GPS, <1 kpc) and Compact
Steep Spectrum (CSS, < 20 kpc) radio sources, up to the large-scale (> 20 kpc)
classical doubles (FR II radio sources). We investigate the dependence of host
galaxy properties (including near-IR surface brightness profiles) on radio
source size, using both our own and published data. The absolute magnitudes and
surface brightness profiles are consistent with the host galaxies being regular
giant elliptical galaxies rather than Brightest Cluster Galaxies (BCGs). We
find that the GPS, CSS, and FR II host galaxies are a uniform class of objects,
consistent with a scenario in which a powerful radio source evolves along this
size sequence.

</DOC>
<DOC>
<DOCNO> 119937 </DOCNO>
ORFEUS II Echelle spectra: Molecular hydrogen at high velocities toward


  Absorption lines of interstellar molecular hydrogen in the far ultraviolet
(FUV) have been observed in the spectrum of the O9.5 halo star HD 93521,
located some 1500 pc from the Galactic plane. During the second flight of the
ORFEUS-SPAS mission a spectrum with the Echelle spectrometer has been recorded
with a total integration time of 1740 s. The resolution achieved was about
10.000 with a signal-to-noise ratio of up to 25. For the first time two
components of molecular hydrogen have been observed in absorption at velocities
of -12 km/s in the Galactic disk and at -62 km/s located presumably in the
Galactic halo. The column densities derived from a standard curve of growth
analysis were found to be N(H_2) = 10^17.0 cm^-2 for the disk component and
N(H_2) = 10^14.6 cm^-2 respectively for the component located in the Galactic
halo.

</DOC>
<DOC>
<DOCNO> 122493 </DOCNO>
Ionization Sources and Physical Conditions in the Diffuse Ionized Gas


  Deep long-slit spectra of the diffuse ionized gas halos of the edge-on spiral
galaxies NGC 4302 and UGC 10288 are presented. These data, along with
previously presented data for NGC 5775 and NGC 891, are used to address the
issue of how DIG halos are energized. Composite photo-ionization/shock models
are generally better at explaining runs of line ratios in these galaxies than
photo-ionization models alone. Models of line ratios in NGC 5775 require a
greater contribution from shocks for filamentary regions than for
non-filamentary regions to explain the run of [OIII]/Halpha. In either case,
the [SII]/[NII] ratio is not well fit by the models. Composite models for UGC
10288 are successful at reproducing the run of [SII]/[NII] for all but the the
highest values of [NII]/Halpha; however, the run of [OIII]/Halpha vs.
[NII]/Halpha does not show any discernible trend, making it difficult to
determine whether or not shocks make a contribution.
  We also examine whether the data can be explained simply by an increase in
temperature with z in a pure photo-ionization model. Runs of [SII]/Halpha,
[NII]/Halpha, and [SII]/[NII] in each of the four galaxies are consistent with
such an increase. However, the runs of [OIII]/Halpha vs. z in NGC 5775 and UGC
10288 require unusually high ionization fractions of O^{++} that can not be
explained without invoking a secondary ionization source or at the very least a
much higher temperature for the [OIII]-emitting component than for the [SII]-
and [NII]-emitting component. An increase in temperature with z is generally
more successful at explaining the [OIII]/Halpha run in NGC 891.

</DOC>
<DOC>
<DOCNO> 118736 </DOCNO>
Driven-disk model for binaries with precessing donor star.


  We present the results of three-dimensional numerical simulations of mass
transfer in semi-detached binary with a donor star whose rotation vector
precesses around the orbital rotation axis of the binary in the observer's
coordinate frame. The calculations support our previous model of flow without a
`hot spot'. Characteristic features of the flow in this model, such as the
formation of an circumbinary envelope, the absence of a `hot spot' at the edge
of the accretion disk, and the formation of a shock wave along the edge of the
stream, are also present in the solution for a binary with precessing donor
star. The parameters of accretion disk and of the structure of the near-disk
regions recur with the precessional period of the rotation axis of donor star.

</DOC>
<DOC>
<DOCNO> 101326 </DOCNO>
Quantized reduction as a tensor product


  Symplectic reduction is reinterpreted as the composition of arrows in the
category of integrable Poisson manifolds, whose arrows are isomorphism classes
of dual pairs, with symplectic groupoids as units. Morita equivalence of
Poisson manifolds amounts to isomorphism of objects in this category.
  This description paves the way for the quantization of the classical
reduction procedure, which is based on the formal analogy between dual pairs of
Poisson manifolds and Hilbert bimodules over C*-algebras, as well as with
correspondences between von Neumann algebras. Further analogies are drawn with
categories of groupoids (of algebraic, measured, Lie, and symplectic type). In
all cases, the arrows are isomorphism classes of appropriate bimodules, and
their composition may be seen as a tensor product. Hence in suitable categories
reduction is simply composition of arrows, and Morita equivalence is
isomorphism of objects.

</DOC>
<DOC>
<DOCNO> 70274 </DOCNO>
Schematic Method for Estimation of CP Asymmetry in Neutrino Oscillation


  Within the framework of three generations of leptons the schematical method
for estimating CP asymmetry in neutrino oscillations is considered. We
introduce a unitarity triangle corresponding to \nu_e-\nu_{\mu} oscillation, in
addition, we show that it is convenient for the estimation to define another
new triangle. CP asymmetry is determined by the difference between the shapes
of a unitarity triangle and new triangle. As results, (i) we show that CP
asymmetry becomes maximal if the shapes of these two triangles are the same.
(ii) We can easily estimate L/E which leads almost 100% asymmetry using this.
(iii) In \nu_e-\nu_{\mu} oscillation with \sin^2 2\theta_{13} \simeq 0.04, we
obtain about 90% asymmetry for LMA MSW scenario and 3% asymmetry for SMA MSW
scenario within long baseline neutrino expriments to be realized in near
future.

</DOC>
<DOC>
<DOCNO> 8580 </DOCNO>
Dissipative dynamics of Bose condensates in optical cavities


  We study the zero temperature dynamics of Bose-Einstein condensates in driven
high-quality optical cavities in the limit of large atom-field detuning. We
calculate the stationary ground state and the spectrum of coupled atom and
field mode excitations for standing wave cavities as well as for travelling
wave cavities. Finite cavity response times lead to damping or controlled
amplification of these excitations. Analytic solutions in the Lamb-Dicke
expansion are in good agreement with numerical results for the full problem and
show that oscillation frequencies and the corresponding damping rates are
qualitatively different for the two cases.

</DOC>
<DOC>
<DOCNO> 121976 </DOCNO>
Submillimeter Wave Astronomy Satellite Observations of Extended Water


  We have used the Submillimeter Wave Astronomy Satellite to map the
ground-state 1_{10}-1_{01} transition of ortho-water at 557 GHz in the Orion
molecular cloud. Water emission was detected in Orion over an angular extent of
about 20 arcmin, or nearly 3 pc. The water emission is relatively weak, with
line widths (3-6 km s^{-1}) and V_{LSR} velocities (9-11 km s^{-1}) consistent
with an origin in the cold gas of the molecular ridge. We find that the
ortho-water abundance relative to H_2 in the extended gas in Orion varies
between 1 and 8x10^{-8}, with an average of 3x10^{-8}. The absence of
detectable narrow-line ortho-H_2^{18}O emission is used to set a 3-sigma upper
limit on the relative ortho-water abundance of 7x10^{-8}.

</DOC>
<DOC>
<DOCNO> 178664 </DOCNO>
Muon capture on nuclei with N > Z, random phase approximation, and


  We use the random phase approximation to describe the muon capture rate on
${}^{44}$Ca,${}^{48}$Ca, ${}^{56}$Fe, ${}^{90}$Zr, and ${}^{208}$Pb. With
${}^{40}$Ca as a test case, we show that the Continuum Random Phase
Approximation (CRPA) and the standard RPA give essentially equivalent
descriptions of the muon capture process. Using the standard RPA with the free
nucleon weak form factors we reproduce the experimental total capture rates on
these nuclei quite well. Confirming our previous CRPA result for the $N = Z$
nuclei, we find that the calculated rates would be significantly lower than the
data if the in-medium quenching of the axial-vector coupling constant were
employed.

</DOC>
<DOC>
<DOCNO> 121833 </DOCNO>
The "Twin Jet" Planetary Nebula M2-9


  We present a model for the structure, temporal behavior, and evolutionary
status of the bipolar nebula M2-9. According to this model the system consists
of an AGB or post-AGB star and a hot white dwarf companion, with an orbital
period of about 120 years. The white dwarf has undergone a symbiotic nova
eruption about 1200 years ago, followed by a supersoft x-ray source phase. The
positional shift of the bright knots in the inner nebular lobes is explained in
terms of a revolving ionizing source. We show that the interaction between the
slow, AGB star's wind, and a collimated fast wind from the white dwarf clears a
path for the ionizing radiation in one direction, while the radiation is
attenuated in others. This results in the mirror-symmetric (as opposed to the
more common point-symmetric) shift in the knots. We show that M2-9 provides an
important evolutionary link among planetary nebulae with binary central stars,
symbiotic systems, and supersoft x-ray sources.

</DOC>
<DOC>
<DOCNO> 102035 </DOCNO>
Symplectic Topology of Integrable Hamiltonian Systems, II: Topological


  The main purpose of this paper is to give a topological and symplectic
classification of completely integrable Hamiltonian systems in terms of
characteristic classes and other local and global invariants.

</DOC>
<DOC>
<DOCNO> 10862 </DOCNO>
Yang-Lee and Fisher Zeros of Multisite Interaction Ising Models on the


  A general analytical formula for recurrence relations of multisite
interaction Ising models in an external magnetic field on the Cayley-type
lattices is derived. Using the theory of complex analytical dynamics on the
Riemann sphere, a numerical algorithm to obtain Yang-Lee and Fisher zeros of
the models is developed. It is shown that the sets of Yang-Lee and Fisher zeros
are almost always fractals, that could be associated with Mandelbrot-like sets
on the complex magnetic field and temperature planes respectively.

</DOC>
<DOC>
<DOCNO> 8528 </DOCNO>
Abrupt Change of Josephson Plasma Frequency at the Phase Boundary of the


  We report the first detailed and quantitative study of the Josephson coupling
energy in the vortex liquid, Bragg glass and vortex glass phases of
Bi_2Sr_2CaCu_2O_{8+\delta} by the Josephson plasma resonance. The measurements
revealed distinct features in the T- and H-dependencies of the plasma frequency
$\omega_{pl}$ for each of these three vortex phases. When going across either
the Bragg-to-vortex glass or the Bragg-to-liquid transition line, $\omega_{pl}$
shows a dramatic change. We provide a quantitative discussion on the properties
of these phase transitions, including the first order nature of the
Bragg-to-vortex glass transition.

</DOC>
<DOC>
<DOCNO> 179020 </DOCNO>
One Body Density Matrix, Natural Orbits and Quasi Hole States in 16O and


  The one body density matrix, momentum distribution, natural orbits and quasi
hole states of 16O and 40Ca are analyzed in the framework of the correlated
basis function theory using state dependent correlations with central and
tensor components. Fermi hypernetted chain integral equations and single
operator chain approximation are employed to sum cluster diagrams at all
orders. The optimal trial wave function is determined by means of the
variational principle and the realistic Argonne v8' two-nucleon and Urbana IX
three-nucleon interactions. The correlated momentum distributions are in good
agreement with the available variational Monte Carlo results and show the well
known enhancement at large momentum values with respect to the independent
particle model. Diagonalization of the density matrix provides the natural
orbits and their occupation numbers. Correlations deplete the occupation number
of the first natural orbitals by more than 10%. The first following ones result
instead occupied by a few percent. Jastrow correlations lower the spectroscopic
factors of the valence states by a few percent (~1-3%) and an additional ~8-12%
depletion is provided by tensor correlations. It is confirmed that short range
correlations do not explain the spectroscopic factors extracted from (e,e'p)
experiments. 2h-1p perturbative corrections in the correlated basis are
expected to provide most of the remaining strength, as in nuclear matter.

</DOC>
<DOC>
<DOCNO> 68579 </DOCNO>
Physics with an e+e- Linear Collider at High Luminosity


  The physics potential is briefly summarized for an e+e- linear collider
operating at center-of-mass energies up to \sqrt{s} = 1 TeV and delivering
integrated luminosities up to \int L = 0.5 ab^(-1) in one to two years. This
machine will allow us to perform precision studies of the top quark and the
electroweak gauge bosons at the per-mille level. It will be an ideal instrument
to investigate the properties of the Higgs boson and to establish essential
elements of the Higgs mechanism as the fundamental mechanism for breaking the
electroweak symmetries. In the area beyond the Standard Model, new particles
and their interactions can be discovered and explored comprehensively. In
supersymmetric theories, the mechanism of the symmetry breaking can be
investigated experimentally and the underlying unified theory can be
reconstructed. The high precision allows stable extrapolations up to scales
near the Planck mass.

</DOC>
<DOC>
<DOCNO> 102609 </DOCNO>
Monoidal uniqueness theorems for stable homotopy theory


  We show that the monoidal product on the stable homotopy category of spectra
is essentially unique. This strengthens work of this author with Schwede on the
uniqueness of models of the stable homotopy theory of spectra. As an
application we show that with an added assumption about underlying model
structures Margolis' axioms uniquely determine the stable homotopy category of
spectra up to monoidal equivalence. Also, the equivalences constructed here
give a unified construction of the known equivalences of the various symmetric
monoidal categories of spectra (S-modules, \W-spaces, orthogonal spectra,
simplicial functors) with symmetric spectra. The equivalences of modules,
algebras and commutative algebras in these categories are also considered.

</DOC>
<DOC>
<DOCNO> 174593 </DOCNO>
Decay of proton-rich nuclei between 39Ti and 49Ni


  Decay studies of very neutron-deficient nuclei ranging from 39Ti to 49Ni have
been performed during a projectile fragmentation experiment at the GANIL/LISE3
separator. For all nuclei studied in this work, 39,40Ti, 42,43Cr, 46Mn,
45,46,47Fe and 49Ni, half-lives and decay spectra have been measured. In a few
cases, gamma coincidence measurements helped to successfully identify the
initial and final states of transitions. In these cases, partial decay scheme
are proposed. For the most exotic isotopes, 39Ti, 42Cr, 45Fe and 49Ni, which
are candidates for two-proton radioactivity from the ground state, no clear
evidence of this process is seen in our spectra and we conclude rather on a
delayed particle decay.

</DOC>
<DOC>
<DOCNO> 80691 </DOCNO>
Vortices and confinement in hot and cold D=2+1 gauge theories


  We calculate the variation with temperature of the vortex free energy in
D=2+1 SU(2) lattice gauge theories. We do so both above and below the
deconfining transition at T=Tc. We find that this quantity is zero at all T for
large enough volumes. For T<Tc this observation is consistent with the fact
that the phase is linearly confining; while for T>Tc it is consistent with the
conventional expectation of `spatial' linear confinement. In small spatial
volumes this quantity is shown to be non-zero. The way it decreases to zero
with increasing volume is shown to be controlled by the (spatial) string
tension and it has the functional form one would expect if the vortices being
studied were responsible for the confinement at low T, and for the `spatial'
confinement at large T. We also discuss in detail some of the direct numerical
evidence for a non-zero spatial string tension at high T, and we show that the
observed linearity of the (spatial) potential extends over distances that are
large compared to typical high-T length scales.

</DOC>
<DOC>
<DOCNO> 152385 </DOCNO>
A two point function in a cascading N=1 gauge theory from supergravity


  We compute the two point correlation function of a dimension 4 operator in a
nonconformal cascading N=1 SUSY gauge theory using the supergravity dual found
by Klebanov and Strassler[hep-th/0007191]. The two point function has a
logarithmic correction to conformal behavior which is related to the scale
dependence of the effective number of colors. The nonsingular behavior of this
correlator suggests that the theory remains a local 4-dimensional quantum field
theory at all scales. We also compute the spectrum of low-lying glueball modes
corresponding to the above operator.

</DOC>
<DOC>
<DOCNO> 99745 </DOCNO>
Equivalences of real submanifolds in complex space


  We show that for any real-analytic submanifold M in C^N there is a proper
real-analytic subvariety V contained in M such that for any point p in M\V, any
real-analytic submanifold M' in C^N, and any point p' in M', the germs of the
submanifolds M and M' at p and p' respectively are formally equivalent if and
only if they are biholomorphically equivalent. More general results for
k-equivalences are also stated and proved.

</DOC>
<DOC>
<DOCNO> 152137 </DOCNO>
Trimming the Tachyon String Field with SU(1,1)


  A discrete symmetry of the string field tachyon condensate noted by Hata and
Shinohara is identified as a discrete subgroup of an SU(1,1) symmetry acting on
the ghost coordinates. This symmetry, known from early studies of free gauge
invariant string field actions, extends to off-shell interactions only for very
restricted kinds of string vertices, among them the associative vertex of cubic
string field theory. It follows that the string field relevant for tachyon
condensation can be trimmed down to SU(1,1) singlets.

</DOC>
<DOC>
<DOCNO> 71627 </DOCNO>
Neutrino mixing in the seesaw model


  In the seesaw model with hierarchical Dirac masses, the neutrino mixing angle
exhibits the behavior of a narrow resonance. In general, the angle is strongly
suppressed, but it can be maximal for special parameter values. We delineate
the small regions in which this happens, for the two flavor problem. On the
other hand, the physical neutrino masses are hierarchical, in general, except
in a large part of the region in which the mixing angle is sizable, where they
are nearly degenerate. Our general analysis is also applicable to the RGE of
neutrino mass matrix, where we find analytic solutions for the running of
physical parameters, in addition to a complex RGE invariant relating them. It
is also shown that, if one mixing angle is small, the three neutrino problem
reduces to two, two flavor problems.

</DOC>
<DOC>
<DOCNO> 121746 </DOCNO>
A group of galaxies around the giant spiral NGC 6946


  We present large-scale CCD images of a dozen low surface brightness objects
in the vicinity of giant Sc galaxy NGC 6946, which have been found recently on
POSS-II copies. Six of them: UGC 11583, kk251, kk252, kkr55, kkr56, and kkr59
are dwarf irregular galaxies resolved into stars. We determined their distances
from the luminosity of the brightest blue stars. The mean estimated distance to
the NGC 6946 group is 5.9 +- 0.4 Mpc. Together with Cepheus 1, discovered
before, the group consist of 8 late type galaxies. Almost all of them are
detected or marginally detected in the HI line. The group is characterized by a
linear projected diameter of 420 kpc, a radial velocity dispersion of 95 km/s,
and a virial mass-to-luminosity ratio about 56 M_sun/L_sun.

</DOC>
<DOC>
<DOCNO> 121839 </DOCNO>
QSO Absorption Lines, Gaseous Infall and Star Formation


  We investigate the impact of recent observational advances in research on the
gaseous content of the universe on our knowledge of star formation histories of
disk galaxies. Several contemporary surveys indicate that large quantities of
gas which has not been astrated or has been astrated only weakly are bound to
galaxies at later epochs ($z\le 1$).

</DOC>
<DOC>
<DOCNO> 40627 </DOCNO>
Measurement of the cross-section and forward-backward charge asymmetry


  We have studied inclusive muon events using all the data collected by the
TOPAZ detector at sqrt(s)=58 GeV with an integrated luminosity of 273pb-1. From
1328 inclusive muon events, we measured the ratio R_qq of the cross section for
qq-bar production to the total hadronic cross section and forward-backward
asymmetry A^q_FB for b and c quarks. The obtained results are R_bb =
0.13+-0.02(stat)+-0.01(syst), R_cc = 0.36+-0.05(stat)+-0.05(syst), A^b_FB =
-0.20+-0.16(stat)+-0.01(syst) and A^c_FB = -0.17+-0.14(stat)+-0.02(syst), in
fair agreement with a prediction of the standard model.

</DOC>
<DOC>
<DOCNO> 151660 </DOCNO>
Conserved charges of non-yangian type for the Frahm-Polychronakos spin


  Through an $\hbar$-expansion of the confined Calogero model with spin
exchange interactions, we extract a generating function for the involutive
conserved charges of the Frahm-Polychronakos spin chain. The resulting
conservation laws possess the spin chain yangian symmetry, although they are
not expressible in terms of these yangians.

</DOC>
<DOC>
<DOCNO> 84085 </DOCNO>
The Central Singularity in Spherical Collapse


  The gravitational strength of the central singularity in spherically
symmetric space-times is investigated. Necessary conditions for the singularity
to be gravitationally weak are derived and it is shown that these are violated
in a wide variety of circumstances. These conditions allow conclusions to be
drawn about the nature of the singularity without having to integrate the
geodesic equations. In particular, any geodesic with a non-zero amount of
angular momentum which impinges on the singularity terminates in a strong
curvature singularity.

</DOC>
<DOC>
<DOCNO> 122847 </DOCNO>
Accretion and Outflow Traced by Water Masers in the Circinus AGN


  The first VLBI images of water maser emission in the Circinus Galaxy AGN show
both a warped, edge-on accretion disk and an outflow 0.1 to 1 pc from the
central engine. The inferred central mass is 1.3 million suns, while the disk
mass may be on the order of 0.1 million suns, based on a nearly Keplerian
rotation curve. The bipolar, wide-angle outflow appears to contain ``bullets''
ejected from within <0.1 pc of the central mass. The positions of filaments and
bullets observed in the AGN ionization cone on kpc-scales suggest that the disk
channels the flow to a radius of about 0.4 pc, at which the flow appears to
disrupt the disk.

</DOC>
<DOC>
<DOCNO> 10821 </DOCNO>
Transmission through quantum networks


  We propose a simple formalism to calculate the conductance of any quantum
network made of one-dimensional quantum wires. We apply this method to analyze,
for two periodic systems, the modulation of this conductance with respect to
the magnetic field. We also study the influence of an elastic disorder on the
periodicity of the AB oscillations and we show that a recently proposed
localization mechanism induced by the magnetic field resists to such a
perturbation. Finally, we discuss the relevance of this approach for the
understanding of a recent experiment on GaAs/GaAlAs networks.

</DOC>
<DOC>
<DOCNO> 118556 </DOCNO>
Nonlinear Shock Acceleration and Photon Emission in Supernova Remnants


  We have extended a simple model of nonlinear diffusive shock acceleration
(Berezhko and Ellison 1999) to include the injection and acceleration of
electrons and the production of photons from bremsstrahlung, synchrotron,
inverse-Compton, and pion-decay processes. We argue that the results of this
model, which is simpler to use than more elaborate ones, offer a significant
improvement over test-particle, power-law spectra which are often used in
astrophysical applications of diffusive shock acceleration. With an
evolutionary supernova remnant (SNR) model to obtain shock parameters as
functions of ambient interstellar medium parameters and time, we predict
broad-band continuum photon emission from supernova remnants in general, and
SN1006 in particular, showing that our results compare well with the more
complete time-dependent and spherically symmetric nonlinear model of Berezhko,
Ksenofontov, and Petukhov (1999). We discuss the implications nonlinear shock
acceleration has for X-ray line emission, and use our model to describe how
ambient conditions determine the TeV/radio flux ratio, an important parameter
for gamma-ray observations of radio SNRs.

</DOC>
<DOC>
<DOCNO> 100896 </DOCNO>
Quantum periods - I. Semi-infinite variations of Hodge structures


  We introduce a generalization of variations of Hodge structures living over
moduli spaces of non-commutative deformations of complex manifolds. Hodge
structure associated with a point of such moduli space is an element of Sato
type grassmanian of semi-infinite subspaces in H^*(X,C)[[h^{-1},h]]. Periods
associated with such semi-infinite Hodge structures serve in order to extend
mirror symmetry relations in dimensions greater then three.

</DOC>
<DOC>
<DOCNO> 118229 </DOCNO>
Absence of "Ghost Images" Excludes Large Values of the Cosmological


  We used the 1.4 GHz NRAO NVSS survey to search for ghost images of radio
sources, expected in cosmologies with a positive cosmological constant and
positive space curvature. No statistically significant evidence for ghost
images was found, placing constraints on the values of L, the space curvature
or the duration of the radio-luminous phase of extragalactic radio sources.

</DOC>
<DOC>
<DOCNO> 150915 </DOCNO>
Aspects of Gauge Theory - Gravity Correspondence


  A brief review of aspects of gravity gauge theory correspondance inspired by
string theory is presented.

</DOC>
<DOC>
<DOCNO> 117823 </DOCNO>
Early spectroscopic observations of Nova (V1494) Aquilae 1999 No.2


  Low- and medium resolution spectra of the fast nova, Nova (V1494) Aql 1999
No.2 obtained approximately 6, 7, 19 and 28 days after the maximum brightness
are presented and discussed. The spectrum covering the whole optical range at
day 6 shows the principal plus diffuse-enhanced spectrum. The presence of
strong Fe II multiplets with P-Cyg profiles suggest that V1494 Aql belongs to
the ``Fe II'' class defined by Williams (1992). The medium-resolution profiles
(lambda/Delta lambda \approx 7000) of the Hgamma and Hdelta lines show
well-defined sharp absorption features with the same radial velocities, while
the Halpha split into two distinct emission peaks in the last two spectra
(Delta t=19 and 28 days). The observed behaviour suggests an expanding
equatorial ring with possible small-scale clumpiness in the nova shell.
  The visual lightcurve is used to deduce M_V by the maximum magnitude versus
rate of decline relationship. The resulting parameters are: t_2=6.6+/-0.5 days,
t_3=16+/-0.5 days, M_V=-8.8+/-0.2 mag. Adopting this value, a distance
d=3.6+/-0.3 kpc is determined.

</DOC>
<DOC>
<DOCNO> 85175 </DOCNO>
Gravitational waves from a spinning particle scattered by a relativistic


  We study gravitational waves from a spinning test particle scattered by a
relativistic star using a perturbation method. The present analysis is
restricted to axial modes. By calculating the energy spectrum, the waveforms
and the total energy and angular momentum of gravitational waves, we analyze
the dependence of the emitted gravitational waves on a particle spin. For a
normal neutron star, the energy spectrum has one broad peak whose
characteristic frequency corresponds to the angular velocity at the turning
point (a periastron). Since the turning point is determined by the orbital
parameter, there exists the dependence of the gravitational wave on a particle
spin. We find that the total energy of $l = 2$ gravitational waves gets larger
as the spin increases in the anti-parallel direction to the orbital angular
momentum. For an ultracompact star, in addition to such an orbital
contribution, we find the quasi-normal modes exited by a scattered particle,
whose excitation rate to gravitational waves depends on the particle spin. We
also discuss the ratio of the total angular momentum to the total energy of
gravitational waves and explain its spin dependence.

</DOC>
<DOC>
<DOCNO> 11255 </DOCNO>
A very low temperature STM for the local spectroscopy of mesoscopic


  We present the design and operation of a very-low temperature Scanning
Tunneling Microscope (STM) working at $60 mK$ in a dilution refrigerator. The
STM features both atomic resolution and micron-sized scanning range at low
temperature. This work is the first experimental realization of a local
spectroscopy of mesoscopic structures at very low temperature. We present
high-resolution current-voltage characteristics of tunnel contacts and the
deduced local density of states of hybrid Superconductor-Normal metal systems.

</DOC>
<DOC>
<DOCNO> 85335 </DOCNO>
Decoherence: A dynamical approach to superselection rules?


  It is well known that the dynamical mechanism of decoherence may cause
apparent superselection rules, like that of molecular chirality. These
`environment-induced' or `soft' superselection rules may be contrasted with
`hard' superselection rules, like that of electric charge, whose existence is
usually rigorously demonstrated by means of certain symmetry principles. We
address the question of whether this distinction between `hard' and `soft' is
well founded and argue that, despite first appearance, it might not be. For
this we give a detailed and somewhat pedagogical exposition of the basic
structural properties of the spaces of states and observables in order to
establish a fairly precise notion of superselection rules. We then discuss two
examples: the Bargmann superselection rule for overall mass in ordinary quantum
mechanics, and the superselection rule for charge in quantum electrodynamics.

</DOC>
<DOC>
<DOCNO> 13959 </DOCNO>
Indivisibility of electron bubbles in helium


  A recent proposal by Maris[1], that single electron bubbles in helium might
fission into separate, particle-like entities, does not properly take into
account the failure of the adiabatic approximation when, due to tunneling,
there is a long electronic time scale. The point along the fission pathway of a
photoexcited p-state bubble, where the adiabatic approximation first breaks
down, occurs well before the bubble waist has pinched down forming two
cavities. In the connected two-lobed geometry, the p- and s-states are strongly
mixed by an antisymmetric vibrational mode, and the excitation decays by the
mechanism where one lobe collapses while the other expands into the spherical
s-state geometry. The extreme pressure jump in a photoexcited bubble leads to
shock formation that may halt the elongation even before adiabaticity is
compromised. In this case, the photoexcited bubble decays radiatively from the
relaxed p-state geometry.
  [1] H.J. Maris, On the fission of elementary particles and the evidence for
fractional electrons in liquid helium, J. Low Temp. Phys. 120, 173 (2000)

</DOC>
<DOC>
<DOCNO> 169575 </DOCNO>
Hybrid exciton-polaritons in a bad microcavity containing the organic


  We study the hybrid exciton-polaritons in a bad microcavity containing the
organic and inorganic quantum wells. The corresponding polariton states are
given. The analytical solution and the numerical result of the stationary
spectrum for the cavity field are finished

</DOC>
<DOC>
<DOCNO> 123068 </DOCNO>
A census with ROSAT of low-luminosity X-ray sources in globular clusters


  I analyze 101 observations from the ROSAT archive to search for X-ray sources
in or near 55 globular clusters. New sources are found in the cores of NGC362
(a double source), NGC6121 (marginally significant), NGC6139, and NGC6266; and
outside the cores of NGC6205, NGC6352 and NGC6388. More accurate positions are
determined for the X-ray sources in some ten clusters. The improved position
for the source in NGC6341 excludes the suggested ultraviolet counterpart. It is
shown that one of the two sources reported near the core NGC6626 is spurious,
as is the detection of a pulsar period in the PSPC data of this cluster; the
central source is resolved in three sources. One source reported previously in
NGC6304 is demoted to an upper limit. For 20 cluster cores better upper limits
to the X-ray luminosity are obtained.
  From a statistical analysis I argue that several sources outside the cluster
cores may well belong to the clusters. All spectral energy distributions
observed so far are relatively soft, with bremsstrahlung temperatures =~0.9keV;
there is evidence however that bremsstrahlung spectra do not correctly describe
the spectra. The X-ray luminosity per unit mass for the cluster as a whole does
not depend on the concentration; the luminosity per unit mass for the core may
increase with the cluster concentration.

</DOC>
<DOC>
<DOCNO> 84368 </DOCNO>
Temporal Ordering in Quantum Mechanics


  We examine the measurability of the temporal ordering of two events, as well
as event coincidences. In classical mechanics, a measurement of the
order-of-arrival of two particles is shown to be equivalent to a measurement
involving only one particle (in higher dimensions). In quantum mechanics, we
find that diffraction effects introduce a minimum inaccuracy to which the
temporal order-of-arrival can be determined unambiguously. The minimum
inaccuracy of the measurement is given by 1/E where E is the total kinetic
energy of the two particles. Similar restrictions apply to the case of
coincidence measurements.

</DOC>
<DOC>
<DOCNO> 8181 </DOCNO>
Nature of phase transitions in a probabilistic cellular automaton with


  We present a probabilistic cellular automaton with two absorbing states,
which can be considered a natural extension of the Domany-Kinzel model. Despite
its simplicity, it shows a very rich phase diagram, with two second-order and
one first-order transition lines that meet at a tricritical point. We study the
phase transitions and the critical behavior of the model using mean field
approximations, direct numerical simulations and field theory. A closed form
for the dynamics of the kinks between the two absorbing phases near the
tricritical point is obtained, providing an exact correspondence between the
presence of conserved quantities and the symmetry of absorbing states. The
second-order critical curves and the kink critical dynamics are found to be in
the directed percolation and parity conservation universality classes,
respectively. The first order phase transition is put in evidence by examining
the hysteresis cycle. We also study the "chaotic" phase, in which two replicas
evolving with the same noise diverge, using mean field and numerical
techniques. Finally, we show how the shape of the potential of the
field-theoretic formulation of the problem can be obtained by direct numerical
simulations.

</DOC>
<DOC>
<DOCNO> 101744 </DOCNO>
Characterization of Local Configuration Controllability for a Class of


  We investigate local configuration controllability for mechanical control
systems within the affine connection formalism. Extending the work by Lewis for
the single-input case, we are able to characterize local configuration
controllability for systems with $n$ degrees of freedom and $n-1$ input forces.

</DOC>
<DOC>
<DOCNO> 120532 </DOCNO>
The complex X-ray absorbers of NGC 3516 observed by BeppoSAX


  In this paper we present the analysis of two broad band (0.1-150 keV)
BeppoSAX observations of the Seyfert 1 galaxy NGC 3516. The two observations
were taken 4 months apart, on 1996 November 8 and 1997 March 12 respectively.
We report a dramatic change in the degree of obscuration of the central source
between the two observations, and propose, as possible explanations transient
absorption by either a stationary-state cloud of cold gas crossing the line of
sight, or a varying-state, initially neutral and dense amount of expanding gas
with decreasing density and therefore decreasing opacity. We also report the
detection of a second highly ionized absorber/emitter, which causes deep
FeXVII-XXII K edges at about 7.8 keV to appear in both BeppoSAX spectra of NGC
3516, and possibly produces the soft X-ray continuum emission and the 1 keV
blend of Fe L recombination lines detected during the epoch of heavy nuclear
obscuration.

</DOC>
<DOC>
<DOCNO> 69880 </DOCNO>
Fermionic Zero Modes on Domain Walls


  We study fermionic zero modes in the domain wall background. The fermions
have Dirac and left- and right-handed Majorana mass terms. The source of the
Dirac mass term is the coupling to a scalar field $\Phi$. The source of the
Majorana mass terms could also be the coupling to a scalar field $\Phi$ or a
vacuum expectation value of some other field acquired in a phase transition
well above the phase transition of the field $\Phi$. We derive the fermionic
equations of motion and find the necessary and sufficient conditions for a zero
mode to exist. We also find the solutions numerically. In the absence of the
Majorana mass terms, the equations are solvable analytically. In the case of
massless fermions a zero energy solution exists and we show that although this
mode is not discretely normalizable it is Dirac delta function normalizable and
should be viewed as part of a continuum spectrum rather than as an isolated
zero mode.

</DOC>
<DOC>
<DOCNO> 152061 </DOCNO>
Gravity in the Einstein-Gauss-Bonnet Theory with the Randall-Sundrum


  We obtain the full 5D graviton propagator in the Randall-Sundrum model with
the Gauss-Bonnet interaction. From the decomposition of the graviton propagator
on the brane, we show that localization of gravity arises in the presence of
the Gauss-Bonnet term. We also obtain the metric perturbation for observers on
the brane with considering the brane bending and compute the amplitude of one
massless graviton exchange. For the positive definite amplitude or no ghost
states, the sign of the Gauss-Bonnet coefficient should be negative in our
convention, which is compatible with string amplitude computations. In that
case, the ghost-free condition is sufficient for obtaining the Newtonian
gravity. For a vanishing Gauss-Bonnet coefficient, the brane bending allows us
to reproduce the correct graviton polarizations for the effective 4D Einstein
gravity.

</DOC>
<DOC>
<DOCNO> 116988 </DOCNO>
A Second-Order Stochastic Leap-Frog Algorithm for Langevin Simulation


  Langevin simulation provides an effective way to study collisional effects in
beams by reducing the six-dimensional Fokker-Planck equation to a group of
stochastic ordinary differential equations. These resulting equations usually
have multiplicative noise since the diffusion coefficients in these equations
are functions of position and time. Conventional algorithms, e.g. Euler and
Heun, give only first order convergence of moments in a finite time interval.
In this paper, a stochastic leap-frog algorithm for the numerical integration
of Langevin stochastic differential equations with multiplicative noise is
proposed and tested. The algorithm has a second-order convergence of moments in
a finite time interval and requires the sampling of only one uniformly
distributed random variable per time step. As an example, we apply the new
algorithm to the study of a mechanical oscillator with multiplicative noise.

</DOC>
<DOC>
<DOCNO> 39962 </DOCNO>
alpha_S Evolution from 35 GeV to 202 GeV and Flavour Independence


  Determinations of the strong coupling constant alpha_S at centre-of-mass
energies of 192 through 202 GeV at LEP are presented. The energy evolution of
alpha_S is in agreement with the prediction of QCD. The combined investigation
of
 OPAL and JADE data in the energy range of 35 through 189 GeV yields
alpha_S(m_Z)=0.1187^{+0.0034}_{-0.0019}. The strenght of the strong coupling is
flavour independent if quark mass effects are taken into account.

</DOC>
<DOC>
<DOCNO> 84603 </DOCNO>
Far Field Behavior of Noncompact Static Spherically Symmetric Solutions


  The Einstein equations with small positive cosmological constant coupled to
an SU(2) Yang Mills field admits solutions that possess a coordinate
singularity at a noncritical radius. Here, we prove that these solutions are
otherwise globally smooth and that they asymptotically approach Schwarzschild
deSitter space with a vanishing Yang Mills field.

</DOC>
<DOC>
<DOCNO> 178545 </DOCNO>
Renormalization of the f0(980) and a0(980) scalar resonances in a


  The meson meson interaction in the scalar sector in the presence of a nuclear
medium is studied with particular attention to the change of the properties of
the f0(980) and a0(980) resonances. By using a chiral unitary approach which
generates the f0 and a0 resonances and reproduces their free properties, we
find that the position of the resonances in the medium is barely changed but
their widths are considerably broadened. New many body corrections generating
from higher orders in the chiral Lagrangian plus the contribution from N*h
excitations, not considered before in connection with the pion-pion interaction
in the nuclear medium, are also investigated.

</DOC>
<DOC>
<DOCNO> 122505 </DOCNO>
Towards optimal softening in 3D N-body codes: I. Minimizing the force


  In N-body simulations of collisionless stellar systems, the forces are
softened to reduce the shot noise. Softening modifies gravity at r=|x-y|
smaller than softening length epsilon and the softened forces are increasingly
biased for ever larger epsilon. There is, thus, some optimum between reducing
the fluctuations and introducing a bias. Here, analytical relations are derived
for the amplitudes of the bias and the fluctuations in the limit of small
epsilon and large N. It is shown that the fluctuations of the force are
generated locally, in contrast to the variations of the potential, which
originate from noise in the whole system. Based on the asymptotic relations and
using numerical experiments, I study the dependence of the resulting force
error on N, epsilon, and on the functional form by which Newtonian gravity is
replaced. The Plummer softening, where each body is replaced by a Plummer
sphere of scale radius epsilon, yields significantly larger force errors than
do methods in which the bodies are replaced by density kernels of finite
extent. I also give special kernels, which reduce the errors even further.
These kernels largely compensate the errors made with too small inter-particle
forces at r<epsilon by exceeding Newtonian forces at r epsilon. Additionally,
the possibilities of locally adapting epsilon and of using unequal weights for
the bodies are investigated. These various techniques allow, without increasing
N, to reduce the rms force error by a factor 2 compared to Plummer softening
with constant epsilon. The results of this study are directly relevant to
N-body simulations using direct summation techniques or the tree code.
(abridged)

</DOC>
<DOC>
<DOCNO> 121058 </DOCNO>
The South Atlantic Magnetic Field Anomaly and Its Effect on the


  The theoretical calculations of the production of neutrinos via cosmic rays
incident upon the earth's atmosphere (Barr et al., 1989; Becker-Szendy et al.,
1992; Bugaev & Naumov, 1989; Gaisser et al, 1988; Honda et al., 1995) are
examined. These calculations use a one-dimensional approximation in the
production, transport, and decay of the produced particles. Examined are
various additional effects of the earth's magnetic field and the
three-dimensional nature of the problem which have the effect of decreasing the
calulated ratio of muon neutrinos to electron neutrinos.

</DOC>
<DOC>
<DOCNO> 101186 </DOCNO>
On p-symmetric Heegaard splittings


  We show that every p-fold strictly-cyclic branched covering of a b-bridge
link in $S^3$ admits a p-symmetric Heegaard splitting - in the sense of Birman
and Hilden - of genus $g=(b-1)(p-1)$. This gives a complete converse of one of
the results of the two authors. Moreover, we introduce the concept of weakly
p-symmetric Heegaard splittings and prove similar results in this more general
context.

</DOC>
<DOC>
<DOCNO> 85357 </DOCNO>
General Relativistic Contribution to Polarization of the Cosmic


  We solve the wave equation for the electromagnetic field tensors associated
with the CMBR photons in a universe with scalar metric perturbations. We show
that the coupling of the electromagnetic fields with the curvature associated
with the scalar perturbations gives rise to an optical rotation of the
microwave background photons. The magnitude of the gravitationally generated
V-Stokes parameter anisotropy $\Delta_V$, is however very small compared to the
linear polarisation caused by Thomson scattering.

</DOC>
<DOC>
<DOCNO> 119545 </DOCNO>
Cosmological Reionization Around the First Stars: Monte Carlo Radiative


  We study the evolution of ionization fronts around the first proto-galaxies
by using high resolution numerical cosmological (Lambda+CDM model) simulations
and Monte Carlo radiative transfer methods. We present the numerical scheme in
detail and show the results of test runs from which we conclude that the scheme
is both fast and accurate. As an example of interesting cosmological
application, we study the reionization produced by a stellar source of total
mass M=2 10^8 M_\odot turning on at z=12, located at a node of the cosmic web.
The study includes a Spectral Energy Distribution of a zero-metallicity stellar
population, and two Initial Mass Functions (Salpeter/Larson). The expansion of
the I-front is followed as it breaks out from the galaxy and it is channeled by
the filaments into the voids, assuming, in a 2D representation, a
characteristic butterfly shape. The ionization evolution is very well tracked
by our scheme, as realized by the correct treatment of the channeling and
shadowing effects due to overdensities. We confirm previous claims that both
the shape of the IMF and the ionizing power metallicity dependence are
important to correctly determine the reionization of the universe.

</DOC>
<DOC>
<DOCNO> 9708 </DOCNO>
Coherent and incoherent pumping of electrons in double quantum dots


  We propose a new mode of operation of an electron pump consisting of two
weakly coupled quantum dots connected to reservoirs. An electron can be
transferred within the device at zero bias voltage when it is subjected to
electromagnetic radiation, thereby exciting the double dot. The excited state
can decay by transferring charge from one lead and to the other lead in one
direction. Depending on the energies of the intermediate states in the pumping
cycle, which are controlled by the gate voltages, this transport is either
incoherent via well-known sequential tunneling processes, or coherent via a
inelastic co-tunneling process. The latter novel mode of operation is possible
only when interdot Coulomb charging is important. The D.C. transport through
the system can be controlled by the frequency of the applied radiation. We
concentrate on the resonant case, when the frequency matches the energy
difference for exciting an electron from one dot into the other. The resonant
peaks in the pumping current should be experimentally observable. We have
developed a density matrix approach which describes the dynamics of the system
on timescales much larger than the period of the applied irradiation. In
contrast to previous works we additionally consider the case of slow modulation
of the irradiation amplitude. Harmonic modulation produces additional sidepeaks
in the photoresponse, and pulsed modulation can be used to resolve the Rabi
frequency in the time-averaged current.

</DOC>
<DOC>
<DOCNO> 152040 </DOCNO>
Correspondence between Noncommutative Soliton and Open String/D-brane


  The gaussian damping factor (g.d.f.) and the new interaction vertex with the
symplectic tensor are the characteristic properties of the N-point
scalar-vector scattering amplitudes of the p-p' (p < p') open string system
which realizes noncommutative geometry. The g.d.f. is here interpreted as a
form factor of the Dp-brane by noncommutative U(1) current. Observing that the
g.d.f. is in fact equal to the Fourier transform of the noncommutative
projector soliton introduced by Gopakumar, Minwalla and Strominger, we further
identify the Dp-brane in the zero slope limit with the noncommutative soliton
state. It is shown that the g.d.f. depends only on the total momentum of N-2
incoming/outgoing photons in the zero slope limit. In the description of the
low-energy effective action (LEEA) proposed before, this is shown to follow
from the delta function propagator and the form of the initial/final wave
functions in the soliton sector which resides in x^{m} m= p+1, ...p' dependent
part of the scalar field \Phi(x^\mu, x^m). The three and four point amplitudes
computed from LEEA agree with string calculation. We discuss related issues
which are resummation/lifting of infinite degeneracy and conservation of
momentum transverse to the Dp-brane.

</DOC>
<DOC>
<DOCNO> 152587 </DOCNO>
Newtonian Gravitons and D-brane Collective Coordinates in Wound String


  Recently it was shown that NCOS theories are part of a ten-dimensional theory
known as Non-relativistic Wound string theory. We clarify the sense in which
gravity is present in this theory. We show that Wound string theory contains
exceptional unwound strings, including a graviton, which mediate the previously
discovered instantaneous long-range interactions, but are negligible as
asymptotic states. Unwound strings also provide the expected collective
coordinates for the transverse D-branes in the theory. These and other results
are shown to follow both from a direct analysis of the effect of the NCOS limit
on the parent string theory, and from the worldsheet formalism developed by
Gomis and Ooguri, about which we make some additional remarks. We also devote
some attention to supergravity duals, and in particular show that the open and
closed strings of the theory are respectively described by short and long
strings on the supergravity side.

</DOC>
<DOC>
<DOCNO> 120694 </DOCNO>
Silicate Emission in the TW Hydrae Association


  The TW Hydrae Association is the nearest young stellar association. Among its
members are HD 98800, HR 4796A, and TW Hydrae itself, the nearest known
classical T Tauri star. We have observed these three stars spectroscopically
between 3 and 13 microns. In TW Hya the spectrum shows a silicate emission
feature that is similar to many other young stars with protostellar disks. The
11.2 micron feature indicative of significant amounts of crystalline olivine is
not as strong as in some young stars and solar system comets. In HR 4796A, the
thermal emission in the silicate feature is very weak, suggesting little in the
way of (small silicate) grains near the star. The silicate band of HD 98800
(observed by us but also reported by Sylvester and Skinner (1996)) is
intermediate in strength between TW Hya and HR 4796.

</DOC>
<DOC>
<DOCNO> 67710 </DOCNO>
The eta' in baryon chiral perturbation theory


  We include in a systematic way the eta' in baryon chiral perturbation theory.
The most general relativistic effective Lagrangian describing the interaction
of the lowest lying baryon octet with the Goldstone boson octet and the eta' is
presented up to linear order in the derivative expansion and its heavy baryon
limit is obtained. As explicit examples, we calculate the baryon masses and the
pi N sigma-term up to one-loop order in the heavy baryon formulation. A
systematic expansion in the meson masses is possible, and appearing divergences
are renormalized.

</DOC>
<DOC>
<DOCNO> 119749 </DOCNO>
The Broad Band Spectrum of MXB 1728-34 Observed by BeppoSAX


  We report on the results of a broad band (0.1-100 keV) spectral analysis of
the bursting atoll source MXB 1728-34 observed by the BeppoSAX satellite. Three
bursts were present during this observation. The spectrum during the bursts can
be fitted by a blackbody with a temperature of 2 keV. From the bursts we also
estimate a distance to the source of 5.1 kpc. MXB 1728-34 was in a rather soft
state during the BeppoSAX observation. The persistent spectrum is well fitted
by a continuum consisting of a soft blackbody emission and a comptonized
spectrum. We interpreted the soft component as the emission from the accretion
disk. Taking into account a spectral hardening factor of 1.7, we estimated that
the inner disk radius is $R_{\rm in} \sqrt{\cos i} \sim 20$ km, where i is the
inclination angle. The comptonized component could originate in a spherical
corona, with temperature of 10 keV and optical depth of 5, surrounding the
neutron star. A broad gaussian emission line at 6.7 keV is observed in the
spectrum, probably emitted in the ionized corona or in the inner part of the
disk. Another emission line is present at 1.66 keV.

</DOC>
<DOC>
<DOCNO> 71832 </DOCNO>
Scaling Violations in the $Q^2$ Logarithmic Derivative of $F_2$


  We examine the latest HERA experimental measurements of the $Q^2$ logarithmic
derivative of the proton structure function. We analyze the characteristics of
DGLAP with and without screening, as well as a Regge type model, and compare
their predictions to all available data on $\slope$ including those for fixed
W. Our results show that the present data can be described in pQCD taking into
account shadowing corrections. However, such a description cannot be considered
a conclusive signal of gluon saturation since the experimental data on $\slope$
do not allow one to discriminate between the various approaches, in spite of
their very different construction.

</DOC>
<DOC>
<DOCNO> 72210 </DOCNO>
Analytic Perturbation Theory for QCD observables


  The connection between ghost-free formulations of RG-invariant perturbation
theory in the both Euclidean and Minkowskian regions is studied. Our basic tool
is the "double spectral representation", similar to definition of Adler
function, that stems from first principles of local QFT. It relates real
functions defined in the Euclidean and Minkowskian regions. On this base we
establish a simple relation between -- The trick of resummation of the
$\pi^2$-terms (known from early 80s) for the invariant QCD coupling and
observables in the time-like region and -- Invariant Analytic Approach (devised
a few years ago) with the "analyticized" coupling $\alpha_{\rm an}(Q^2)$ and
nonpower perturbative expansion for observables in the space-like domain which
are free of unphysical singularities . As a result, we formulate a
self-consistent scheme, Analytic Perturbation Theory (APT), that relates a
renorm-invariant, effective coupling functions $\alpha_{an}(Q^2) $ and
$\tilda{alpha}(s),$ as well as non-power perturbation expansions for
observables in both space- and time-like domains, that are free of extra
singularities and obey better convergence in the infrared region. Then we
consider the quark threshold crossing and devise a global APT scheme for the
data analysis in the whole accessible space-like and time-like domain with
various numbers of active quarks. Preliminary estimates indicate that this
global scheme produces results a bit different, sometimes even in the
five-flavour region, on a few per cent level for $\bar{\alpha}_s$ -- from the
usual one, thus influencing the total picture of the QCD parameter correlation.

</DOC>
<DOC>
<DOCNO> 101982 </DOCNO>
Algorithms for the Toric Hilbert Scheme


  The toric Hilbert scheme parametrizes all algebras isomorphic to a given
semigroup algebra as a multigraded vectorspace. All components of the scheme
are toric varieties, and among them, there is a fairly well understood coherent
component. However, it is unknown whether toric Hilbert schemes are always
connected. In this chapter we illustrate the use of Macaulay 2 for exploring
the structure of toric Hilbert schemes. In the process we will encounter
algorithms from commutative algebra, algebraic geometry, polyhedral theory and
geometric combinatorics.

</DOC>
<DOC>
<DOCNO> 71725 </DOCNO>
Large Effects of CP- and T-Violation in K^0 Decay


  The epsilon-impurity of the K_L wave-function gives rise to a huge
CP-violating effect in the decay K_L -> pi^+ pi^- gamma which is hidden in the
polarization state (Stokes vector) of the photon. One component of the Stokes
vector is CP-odd and T-even, and may be identified with circular polarization.
Another component is CP-odd and T-odd (``oblique polarization'') and reveals
itself as a large asymmetry (14%) in the decay K_L -> pi^+ pi^- e^+ e^-.
Striking time-dependent effects are predicted in the angular distribution of
the pi^+ pi^- e^+ e^- system emanating from an initial K^0 or K^0bar state.

</DOC>
<DOC>
<DOCNO> 8131 </DOCNO>
Linear and nonlinear susceptibilities of a decoherent two-level system


  The linear and nonlinear dynamical susceptibilities of a two level system are
calculated as it undergoes a transition to a decoherent state. Analogously to
the Glover-Tinkham-Ferrell sum rule of superconductivity, spectral weight in
the linear susceptibility is continuously transferred from a finite frequency
resonance to nearly zero frequency, corresponding to a broken symmetry in the
thermodynamic limit. For this reason, the behavior of the present model (the
Mermin model) differs significantly from the spin-boson model. The third order
nonlinear susceptibility, corresponding to two-photon absorption, has an
unexpected non-monotonic behavior as a function of the environmental coupling,
reaching a maximum within the decoherent phase of the model. Both linear and
nonlinear susceptibilities may be expressed in a universal form.

</DOC>
<DOC>
<DOCNO> 151393 </DOCNO>
D-brane charges and K-homology


  It is argued that D-brane charge takes values in K-homology. For smooth
manifolds with spin structure, this could explain why the phase factor
$\Omega(x)$ calculated with a D-brane state x in IIB theory appears in
Diaconescu, Moore and Witten's computation of the partition function of IIA
string theory.

</DOC>
<DOC>
<DOCNO> 80996 </DOCNO>
Study of Charmonia near the deconfining transition on an anisotropic


  We study hadron properties near the deconfining transition in the quenched
lattice QCD simulation. This paper focuses on the heavy quarkonium states, such
as $J/\psi$ meson. In order to treat heavy quarks at $T>0$, we adopt the $O(a)$
improved Wilson action on anisotropic lattice. We discuss $c\bar{c}$ bound
state observing the wave function and compare the meson correlators at above
and below $T_c$. Although we find a large change of correlator near the $T_c$,
the strong spatial correlation which is almost the same as confinement phase
survives even $T\sim 1.5T_c$.

</DOC>
<DOC>
<DOCNO> 80754 </DOCNO>
Diquark condensation in two colour QCD


  Unquenched lattice SU(2) is studied at nonzero chemical potential in the
strong coupling limit. The topic of diquark condensation is addressed analyzing
the probability distribution function of the diquark condensate. We present
results at zero external source without using any potentially dangerous
extrapolation procedure. We find strong evidences for a (high density) second
order phase transition where a diquark condensate appears, and show
quantitative agreement of lattice calculations with low-energy effective
Lagrangian calculations.

</DOC>
<DOC>
<DOCNO> 8174 </DOCNO>
Collective Phenonema in the Interaction of Radiation with Matter


  The aim of this communication is to present in a concentrated form the main
ideas of a method, developed by the author, for treating strongly
nonequilibrium collective phenomena typical of the interaction of radiation
with matter, as well as to give a survey of several applications of the method.
The latter is called the Scale Separation Approach since its basic techniques
rely on the possibility of separating different space-time scales in
nonequilibrium statistical systems. This approach is rather general and can be
applied to diverse physical problems, several of which are discussed here.
These problems are: Superradiance of nuclear spins, filamentation in resonant
media, semiconfinement of neutral atoms, negative electric current, and
collective liberation of light.

</DOC>
<DOC>
<DOCNO> 11392 </DOCNO>
Energy landscape of a Lennard-Jones liquid: Statistics of stationary


  Molecular dynamics simulations are used to generate an ensemble of saddles of
the potential energy of a Lennard-Jones liquid. Classifying all extrema by
their potential energy u and number of unstable directions k, a well defined
relation k(u) is revealed. The degree of instability of typical stationary
points vanishes at a threshold potential energy, which lies above the energy of
the lowest glassy minima of the system. The energies of the inherent states, as
obtained by the Stillinger-Weber method, approach the threshold energy at a
temperature close to the mode-coupling transition temperature Tc.

</DOC>
<DOC>
<DOCNO> 102804 </DOCNO>
Are a and d your cup of tea?


  We show that, consistently, every MAD family has cardinality strictly bigger
than the dominating number, that is a > d, thus solving one of the oldest
problems on cardinal invariants of the continuum. The method is a contribution
to the theory of iterated forcing for making the continuum large.

</DOC>
<DOC>
<DOCNO> 69511 </DOCNO>
Supersymmetric Electroweak Baryogenesis


  We re-examine the generation of the baryon asymmetry in the minimal
supersymmetric standard model (MSSM) during the electroweak phase transition.
We find that the dominant source for baryogenesis arises from the chargino
sector. The CP-violation comes from the complex phase in the mu parameter,
which provides CP-odd contributions to the particle dispersion relations. This
leads to different accelerations for particles and antiparticles in the wall
region which, combined with diffusion, leads to the separation of Higgsinos and
their antiparticles in the front of the wall. These asymmetries get transported
to produce perturbations in the left-handed chiral quarks, which then drive
sphaleron interactions to create the baryon asymmetry. We present a complete
derivation of the semiclassical WKB formalism, including the chargino
dispersion relations and a self-consistent derivation of the diffusion
equations starting from semiclassical Boltzmann equations for WKB-excitations.
We stress the advantages of treating the transport equations in terms of the
manifestly gauge invariant physical energy and kinetic momentum, rather than in
the gauge variant canonical variables used in previous treatments. We show that
a large enough baryon asymmetry can be created for the phase of the complex mu
parameter as small as ~ 0.001, which is consistent with bounds from the neutron
electric dipole moment.

</DOC>
<DOC>
<DOCNO> 152280 </DOCNO>
Why do we need supersymmetry?


  These short (personal) notes appeared as the result of my attempt to address
the question raised in the title.

</DOC>
<DOC>
<DOCNO> 152308 </DOCNO>
Fractional D-branes and their gauge duals


  We study the classical geometry associated to fractional D3-branes of type
IIB string theory on R^4/Z_2 which provide the gravitational dual for N=2 super
Yang-Mills theory in four dimensions. As one can expect from the lack of
conformal invariance on the gauge theory side, the gravitational background
displays a repulson-like singularity. It turns out however, that such
singularity can be excised by an enhancon mechanism. The complete knowledge of
the classical supergravity solution allows us to identify the coupling constant
of the dual gauge theory in terms of the string parameters and to find a
logarithmic running that is governed precisely by the beta-function of the N=2
super Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 80688 </DOCNO>
An alternative to domain wall fermions


  We define a sparse hermitian lattice Dirac matrix, $H$, coupling $2n+1$ Dirac
fermions. When $2n$ fermions are integrated out the induced action for the last
fermion is a rational approximation to the hermitian overlap Dirac operator. We
provide rigorous bounds on the condition number of $H$ and compare them to
bounds for the higher dimensional Dirac operator of domain wall fermions. Our
main conclusion is that overlap fermions should be taken seriously as a
practical alternative to domain wall fermions in the context of numerical QCD.

</DOC>
<DOC>
<DOCNO> 84395 </DOCNO>
The Scenario for the Astrophysics with Scalar Field and the Cosmological


  In order to give the standard scenario of the astrophysics, we study the
Einstein theory with minimally coupled scalar field and the cosmological term
by considering the scalar field as a candidate of the dark matter. We obtained
the exact solution in the cosmological scale and the approximate gravitational
potential in the galactic or solar scale. We find that the scalar field plays
the role of the dark matter in some sense in the cosmological scale but it does
not play the role of the dark matter in the galactic or solar scale within our
approximation.

</DOC>
<DOC>
<DOCNO> 178574 </DOCNO>
One-body density matrix and momentum distribution in s-p and s-d shell


  Analytical expressions of the one- and two- body terms in the cluster
expansion of the one-body density matrix and momentum distribution of the s-p
and s-d shell nuclei with N=Z are derived. They depend on the harmonic
oscillator parameter b and the parameter $\beta$ which originates from the
Jastrow correlation function. These parameters have been determined by least
squares fit to the experimental charge form factors. The inclusion of
short-range correlations increases the high momentum component of the momentum
distribution, $n({\bf k})$ for all nuclei we have considered while there is an
A dependence of $n({\bf k})$ both at small values of k and the high momentum
component. The A dependence of the high momentum component of $n({\bf k})$
becomes quite small when the nuclei $^{24}$Mg, $^{28}$Si and $^{32}$S are
treated as 1d-2s shell nuclei having the occupation probability of the 2s-state
as an extra free parameter in the fit to the form factors.

</DOC>
<DOC>
<DOCNO> 118650 </DOCNO>
The Narrow Line Region of Narrow-Line Seyfert 1 Galaxies


  This work studies the optical emission line properties and physical
conditions of the narrow line region (NLR) of seven narrow-line Seyfert 1
galaxies (NLS1). Our results show that the flux carried out by the narrow
component of H-beta is, on average, 50% of the total line flux. As a result,
the [OIII] 5007/H-beta ratio emitted in the NLR varies from 1 to 5, instead of
the universally adopted value of 10. This has strong implications for the
required spectral energy distribution that ionizes the NLR gas. Photoionization
models that consider a NLR composed of a combination of matter-bounded and
ionization-bounded clouds are successful at explaining the low [OIII]
5007/H-beta ratio and the weakness of low-ionization lines of NLS1s. Variation
of the relative proportion of these two type of clouds nicely reproduce the
dispersion of narrow line ratios found among the NLS1 sample. Assuming similar
physical model parameters of both NLS1s and the normal Seyfert 1 galaxy NGC
5548, we show that the observed differences of emission line ratios between
these two groups can be explained in terms of the shape of the input ionizing
continuum. Narrow emission line ratios of NLS1s are better reproduced by a
steep power-law continuum in the EUV -- soft X-ray region, with spectral index
alpha ~ -2. Flatter spectral indices (alpha ~ -1.5) match the observed line
ratios of NGC 5548 but are unable to provide a good match to the NLS1 ratios.
This result is consistent with ROSAT observations of NLS1s, which show that
these objects are characterized by steeper power-law indices than those of Sy1
galaxies with strong broad optical lines.

</DOC>
<DOC>
<DOCNO> 151319 </DOCNO>
Bulk versus boundary (gravitational Casimir) effects in quantum creation


  The role of bulk matter quantum effects (via the corresponding effective
potential discussed on the example of conformal scalar) and of boundary matter
quantum effects (via the conformal anomaly induced effective action) is
considered in brane-world cosmology. Scenario is used where brane tension is
not free parameter, and the initial bulk-brane classical action is defined by
some considerations. The effective bulk-brane equations of motion are analyzed.
The quantum creation of 4d de Sitter or Anti-de Sitter(AdS) brane Universe
living in 5d AdS space is possible when quantum bulk and (or) brane matter is
taken into account. The consideration of only conformal field theory (CFT)
living on the brane admits the full analytical treatment. Then bulk
gravitational Casimir effect leads to deformation of 5d AdS space shape as well
as of shape of spherical or hyperbolic branes. The generalization of above
picture for the dominant bulk quantum gravity naturally represents such
scenario as self-consistent warped compactification within AdS/CFT set-up.

</DOC>
<DOC>
<DOCNO> 10363 </DOCNO>
Absence of overscreened Kondo effect in ferromagnetic host


  We study the low temperature behavior of a boundary magnetic impurity S'=1/2
in an open ferromagnetic Takhatajian-Babujian spin-S chain. For
antiferromagnetic Kondo coupling, it is show via Bethe ansatz solution that the
impurity spin is always locked into the critical behavior the bulk. At low
temperature, a local composite of spin S-1/2 forms near the impurity site and
its contribution to specific heat is of simple power law T^{1/2}. The absence
of overscreened Kondo effect is due to the large correlation length of host
spins which is divergent near the quantum critical point.

</DOC>
<DOC>
<DOCNO> 10542 </DOCNO>
Non-ergodic effects in the Coulomb glass: specific heat


  We present a numerical method for the investigation of non-ergodic effects in
the Coulomb glass. For that, an almost complete set of low-energy many-particle
states is obtained by a new algorithm. The dynamics of the sample is mapped to
the graph formed by the relevant transitions between these states, that means
by transitions with rates larger than the inverse of the duration of the
measurement. The formation of isolated clusters in the graph indicates
non-ergodicity. We analyze the connectivity of this graph in dependence on
temperature, duration of measurement, degree of disorder, and dimensionality,
studying how non-ergodicity is reflected in the specific heat.

</DOC>
<DOC>
<DOCNO> 84426 </DOCNO>
Dynamical content of quantum diffeomorphisms in two-dimensional quantum


  A model for 2D-quantum gravity from the Virasoro symmetry is studied. The
notion of space-time naturally arises as a homogeneous space associated with
the kinematical (non-dynamical) SL(2,R) symmetry in the kernel of the
Lie-algebra central extension for the critical values of the conformal anomaly.
The rest of the generators in the group, L_n (n>1, n<-1), mix space-times with
different constant curvature. Only in the classical limit all space-times can
be identified, defining a unique Minkowski space-time, and the operators L_n
(n<1, n<-1) gauged away. This process entails a restriction to SL(2,R)
subrepresentations, which creates a non-trivial two-dimensional symplectic
classical phase space. The present model thus suggests that the role of general
covariance in quantum gravity is different from that played in the classical
limit.

</DOC>
<DOC>
<DOCNO> 84134 </DOCNO>
Stability of self-gravitating magnetic monopoles


  The stability of a spherically symmetric self-gravitating magnetic monopole
is examined in the thin wall approximation: modeling the interior false vacuum
as a region of de Sitter space; the exterior as an asymptotically flat region
of the Reissner-Nordstr\"om geometry; and the boundary separating the two as a
charged domain wall. There remains only to determine how the wall gets embedded
in these two geometries. In this approximation, the ratio $k$ of the false
vacuum to surface energy densities is a measure of the symmetry breaking scale
$\eta$. Solutions are characterized by this ratio, the charge on the wall $Q$,
and the value of the conserved total energy $M$. We find that for each fixed
$k$ and $Q$ up to some critical value, there exists a unique globally static
solution, with $M\simeq Q^{3/2}$; any stable radial excitation has $M$ bounded
above by $Q$, the value assumed in an extremal Reissner-Nordstr\"om geometry
and these are the only solutions with $M<Q$. As $M$ is raised above $Q$ a black
hole forms in the exterior: (i) for low $Q$ or $k$, the wall is crushed; (ii)
for higher values, it oscillates inside the black hole. If the mass is not too
high these `collapsing' solutions co-exist with an inflating bounce; (iii) for
$k$, $Q$ or $M$ outside the above regimes, there is a unique inflating
solution. In case (i) the course of the bounce lies within a single
asymptotically flat region (AFR) and it resembles closely the bounce exhibited
by a false vacuum bubble (with Q=0). In cases (ii) and (iii) the course of the
bounce spans two consecutive AFRs.

</DOC>
<DOC>
<DOCNO> 69771 </DOCNO>
Bayesian Analysis


  After making some general remarks, I consider two examples that illustrate
the use of Bayesian Probability Theory. The first is a simple one, the
physicist's favorite "toy," that provides a forum for a discussion of the key
conceptual issue of Bayesian analysis: the assignment of prior probabilities.
The other example illustrates the use of Bayesian ideas in the real world of
experimental physics.

</DOC>
<DOC>
<DOCNO> 116623 </DOCNO>
Coherence in a simple network: Implication for brain function


  In a many body system, constituents interact with each other, forming a
recursive pattern of interaction and giving rise to many interesting phenomena.
Based upon concepts of the modern many body theory, a model for a generic many
body system is developed. A novel approach is proposed to investigate the
general features in such a system. An interesting phase transition in the
system is found. Possible link to brain dynamics is discussed. It is shown how
some of the basic brain processes, such as learning and memory, find therein a
natural explanation.

</DOC>
<DOC>
<DOCNO> 102854 </DOCNO>
Finite simple groups and localization


  The purpose of this paper is to explore the concept of localization, which
comes from homotopy theory, in the context of finite simple groups. We give an
easy criterion for a finite simple group to be a localization of some simple
subgroup and we apply it in various cases. Iterating this process allows us to
connect many simple groups by a sequence of localizations. We prove that all
sporadic simple groups (except possibly the Monster) and several groups of Lie
type are connected to alternating groups. The question remains open whether or
not there are several connected components within the family of finite simple
groups.

</DOC>
<DOC>
<DOCNO> 121175 </DOCNO>
Formation and Evolution of E and S0 Galaxies from HST and Keck Studies


  We have witnessed a dramatic increase over the last five years in results on
distant galaxies, in large part because of the high resolution imaging
capability of HST, and the multiobject spectroscopic capability of the Keck
telescopes. Our program to obtain wide-field, multi-color WFPC2 mosaics with
HST of intermediate redshift clusters, and spectroscopic membership and high
S/N spectroscopy with LRIS on Keck, has provided new insights into the nature
of elliptical and S0 galaxies in the cluster environment over a wide range of
densities. In particular, most ellipticals, and a significant fraction of the
S0 population, have large luminosity-weighted ages, suggesting that their
stellar populations were formed at redshifts beyond z~2, though the existence
of substantial numbers of major mergers in MS 1054-03 at z=0.83 suggests that
final assembly of such galaxies may not have occurred until much later for a
significant fraction of early-type galaxies.

</DOC>
<DOC>
<DOCNO> 40590 </DOCNO>
Report of the QCD Tools Working Group


  We report on the activities of the ``QCD Tools for heavy flavors and new
physics searches'' working group of the Run II Workshop on QCD and Weak Bosons.
The contributions cover the topics of improved parton showering and comparisons
of Monte Carlo programs and resummation calculations, recent developments in
Pythia, the methodology of measuring backgrounds to new physics searches,
variable flavor number schemes for heavy quark electro-production, the
underlying event in hard scattering processes, and the Monte Carlo MCFM for NLO
processes.

</DOC>
<DOC>
<DOCNO> 119331 </DOCNO>
Glitches in Southern Pulsars


  Timing observations of 40 mostly young pulsars using the ATNF Parkes radio
telescope between 1990 January and 1998 December are reported. In total, 20
previously unreported glitches and ten other glitches were detected in 11
pulsars. These included 12 glitches in PSR J1341$- $6220, corresponding to a
glitch rate of 1.5 glitches per year. We also detected the largest known
glitch, in PSR J1614$-$5047, with $\Delta\nu_g/\nu \approx 6.5 \times 10^{-6}$
where $\nu = 1/P$ is the pulse frequency. Glitch parameters were determined
both by extrapolating timing solutions to inter-glitch intervals and by
phase-coherent timing fits across the glitch(es). Analysis of glitch
parameters, both from this work and from previously published results, shows
that most glitches have a fractional amplitude $\Delta\nu_g/\nu$ of between
$10^{-8}$ and $10^{-6}$. There is no consistent relationship between glitch
amplitude and the time since the previous glitch or the time to the following
glitch, either for the ensemble or for individual pulsars. As previously
recognised, the largest glitch activity is seen in pulsars with ages of order
10$^4$ years, but for about 30 per cent of such pulsars, no glitches were
detected in the 8-year data span. There is some evidence for a new type of
timing irregularity in which there is a significant increase in pulse frequency
over a few days, accompanied by a decrease in the magnitude of the slowdown
rate. Fits of an exponential recovery to post-glitch data show that for most
older pulsars, only a small fraction of the glitch decays. In some younger
pulsars, a large fraction of the glitch decays, but in others, there is very
little decay.

</DOC>
<DOC>
<DOCNO> 151468 </DOCNO>
The Local Structure of Anomaly Inflow


  Anomaly cancellation for M-theory fivebranes requires the introduction of a
"bump-form" which smoothes out the five-brane source. We discuss the physical
origin of this bump-form in the simpler case of axion strings in 3+1 dimensions
and construct it in terms of the radial profile of the fermion zero modes. Our
treatment allows for a clearer understanding of the role played by covariant
rather than consistent anomalies when anomalies are canceled by inflow from the
bulk. We briefly discuss the generalization of these results to fivebrane
anomalies in M theory.

</DOC>
<DOC>
<DOCNO> 174555 </DOCNO>
Meson Production in p+d Reactions


  The production of neutral and charged pions as well as eta mesons is studied
in the Delta and N* resonance region, respectively. Heavy A=3 recoils were
measured with the GEM detector. The differential cross sections covering the
full angular range are compared with model calculations.

</DOC>
<DOC>
<DOCNO> 118198 </DOCNO>
Single-Particle and Collective Motion for Proton-Rich Nuclei on the


  Based on available experimental data, a new set of Nilsson parameters is
proposed for proton-rich nuclei with proton or neutron numbers $28\leq N\leq
40$. The resulting single-particle spectra are compared with those from
relativistic and non-relativistic mean field theories. Collective excitations
in some even--even proton-rich nuclei in the upper $pf$ shell are investigated
using the Projected Shell Model with the new Nilsson basis. It is found that
the regular bands are sharply disturbed by band crossings involving $1g_{9/2}$
neutrons and protons. Physical quantities for exploring the nature of the band
disturbance and the role of the $1g_{9/2}$ single-particle are predicted, which
may be tested by new experiments with radioactive beams.

</DOC>
<DOC>
<DOCNO> 100563 </DOCNO>
On the asymptotic geometry of abelian-by-cyclic groups


  A finitely presented, torsion free, abelian-by-cyclic group can always be
written as an ascending HNN extension Gamma_M of Z^n, determined by an n x n
integer matrix M with det(M) \ne 0. The group Gamma_M is polycyclic if and only
if |det(M)|=1. We give a complete classification of the nonpolycyclic groups
Gamma_M up to quasi-isometry: given n x n integer matrices M,N with |det(M)|,
|det(N)| > 1, the groups Gamma_M, Gamma_N are quasi-isometric if and only if
there exist positive integers r,s such that M^r, N^s have the same absolute
Jordan form. We also prove quasi-isometric rigidity: if Gamma_M is an
abelian-by-cyclic group determined by an n x n integer matrix M with |det(M)| >
1, and if G is any finitely generated group quasi-isometric to Gamma_M, then
there is a finite normal subgroup K of G such that G/K is abstractly
commensurable to Gamma_N, for some n x n integer matrix N with |det(N)| > 1.

</DOC>
<DOC>
<DOCNO> 117275 </DOCNO>
Finite element approach for simulating quantum electron dynamics in a


  A fast and stable numerical method is formulated to compute the time
evolution of a wave function in a magnetic field by solving the time-dependent
Schroedinger equation. This computational method is based on the finite element
method in real space to improved accuracy without any increase of computational
cost. This method is also based on Suzuki's exponential product theory to
afford an efficient way to manage the TD-Schroedinger equation with a vector
potential. Applying this method to some simple electron dynamics, we have
confirmed its efficiency and accuracy.

</DOC>
<DOC>
<DOCNO> 120047 </DOCNO>
High Energy Gamma-Ray Observations of the Crab Nebula and Pulsar with


  The Solar Tower Atmospheric Cherenkov Effect Experiment (STACEE) is a new
ground-based atmospheric Cherenkov telescope for gamma-ray astronomy. STACEE
uses the large mirror area of a solar heliostat facility to achieve a low
energy threshold. A prototype experiment which uses 32 heliostat mirrors with a
total mirror area of ~ 1200\unit{m^2} has been constructed. This prototype,
called STACEE-32, was used to search for high energy gamma-ray emission from
the Crab Nebula and Pulsar. Observations taken between November 1998 and
February 1999 yield a strong statistical excess of gamma-like events from the
Crab, with a significance of $+6.75\sigma$ in 43 hours of on-source observing
time. No evidence for pulsed emission from the Crab Pulsar was found, and the
upper limit on the pulsed fraction of the observed excess was < 5.5% at the 90%
confidence level. A subset of the data was used to determine the integral flux
of gamma rays from the Crab. We report an energy threshold of E_{th} = 190 \pm
60\unit{GeV}, and a measured integral flux of I (E > E_{th}) = (2.2 \pm 0.6 \pm
0.2) \times 10^{-10}\unit{photons cm^{-2} s^{-1}}. The observed flux is in
agreement with a continuation to lower energies of the power law spectrum seen
at TeV energies.

</DOC>
<DOC>
<DOCNO> 13909 </DOCNO>
Wigner Crystallization in mesoscopic 2D electron systems


  Wigner crystallization of electrons in a 2D quantum dots is reported. It
proceeds in two stages: I) via radial ordering of electrons on shells and II)
freezing of the inter-shell rotation. The phase boundary of the crystal is
computed in the whole temperature--density plane, and the influence of quantum
effects and of the particle number is analyzed.

</DOC>
<DOC>
<DOCNO> 71846 </DOCNO>
Chromomagnetic Catalysis of Color Superconductivity in a


  The influence of a constant uniform external chromomagnetic field $H$ on the
formation of color superconductivity has been investigated. The consideration
was performed in the framework of a (2+1)-dimensional Nambu--Jona-Lasinio model
with two different four-fermionic structures responsible for $<\bar qq>$ and
diquark $<qq>$ condensates. In particular, it was shown that there exists a
critical value $H_c$ of the external chromomagnetic field such that at $H>H_c$
a nonvanishing diquark condensate is dynamically created (the so-called
chromomagnetic catalysis effect of color superconductivity). Moreover, external
chromomagnetic fields may in some cases enhance the diquark condensate of color
superconductivity.

</DOC>
<DOC>
<DOCNO> 121595 </DOCNO>
Dynamical Constraints on the Formation of NGC 4472 and Its Globular


  We present new radial velocities for 87 globular clusters around the
elliptical galaxy NGC 4472, and combine these with our previously published
data to create a data set of velocities for 144 globular clusters around NGC
4472. We utilize this data set to analyze the kinematics of the NGC 4472
globular cluster system. The new data confirms our previous discovery that the
metal-poor clusters have significantly higher velocity dispersion than the
metal-rich clusters in NGC 4472. We also find very little or no rotation in the
more spatially concentrated metal-rich population, with a resulting upper limit
for this population of (v/sigma)_{proj} < 0.34 at a 99% confidence level. The
very small angular momentum in the metal-rich population requires efficient
angular momentum transport during the formation of this population which is
spatially concentrated and chemically enriched. Such angular momentum transfer
can be provided by galaxy mergers, but has not been achieved in other extant
models of elliptical galaxy formation that include dark matter halos. We also
calculate the velocity dispersion as a function of radius, and show that it is
consistent with roughly isotropic orbits for the clusters and the mass
distribution of NGC 4472 inferred from X-ray observations of the hot gas around
the galaxy.

</DOC>
<DOC>
<DOCNO> 119306 </DOCNO>
An Emission-Line Search for Star-Forming Dwarf Galaxies Toward Abell 851


  (Abridged) We present deep, narrow-band images of the redshift 0.41 galaxy
cluster Abell 851 (Cl 0939+4713) which isolate [OII] 3726,29 line emission. The
[OII]-selected galaxies lie within a projected clustercentric distance of 2
Mpc. The sample is complete to magnitude m_{5129}(AB) = 24.0$ for galaxies with
emission-line equivalent widths greater than about 11\angs in the observed
frame. Color, brightness, and equivalent-width criteria are used to identify
foreground interlopers (steep 4000 A break across the filters) and candidates
for Ly-alpha emission at z=3.31. The number density of star-forming galaxies
toward Cl~0939+4713 is three to four times higher than that of a similar column
through the field at z=0.4. Galaxies in the cluster sample have lower [OII]
equivalent widths than similarly selected field galaxies at $z \sim 0.4$
however, and we suggest that while the density of galaxies is higher in the
cluster the star-formation activity in individual galaxies is supressed
relative to their counterparts in the field. The relatively small enhancement
in the surface density of the [OII]-selected population toward the cluster core
leads us to believe the [OII]-selected galaxies reside in the outer regions of
the cluster. We identify a population of starburst galaxies among the
[OII]-emitters based on their blue g-i color. The majority of the
[OII]-selected galaxies appear to be related to the normal spiral galaxy
population, but the bursting population is dominated by intrinsically faint
galaxies of below average size. We suggest that this population is composed
primarily of dwarf galaxies and discuss their relation to the dwarf galaxies in
present day clusters.

</DOC>
<DOC>
<DOCNO> 101791 </DOCNO>
Automorphisms of Finite Order on Rational Surfaces


  We classify minimal pairs (X, G) for smooth rational projective surface X and
finite group G of automorphisms on X. We also determine the fixed locus X^G and
the quotient surface Y = X/G as well as the fundamental group of the smooth
part of Y. The realization of each pair is included. Mori's extremal ray theory
and recent results of Alexeev and also Ambro on the existence of good
anti-canonical divisors are used.

</DOC>
<DOC>
<DOCNO> 102828 </DOCNO>
Vertex operator algebra arising from the minimal series M(3,p) and


  We study a vertex operator algebra (VOA) V related to the M(3,p) Virasoro
minimal series. This VOA reduces in the simplest case p=4 to the level two
integrable vacuum module of $\hat{sl}_2$. On V there is an action of a
commutative current a(z), which is an analog of the current e(z) of
$\hat{sl}_2$. Our main concern is the subspace W generated by this action from
the highest weight vector of V. Using the Fourier components of a(z), we
present a monomial basis of W and a semi-infinite monomial basis of V. We also
give a Gordon type formula for their characters.

</DOC>
<DOC>
<DOCNO> 14048 </DOCNO>
Collapsing dynamics of attractive Bose-Einstein condensates


  The self-similar collapse of 3D and quasi-2D atom condensates with negative
scattering length is examined. 3D condensates are shown to blow up following
the scenario of {\it weak collapse}: The inner core of the condensate diverges
with an almost zero particle number, while its tail distribution spreads out to
large distances with a constant density profile. For this case, the 3-body
recombination arrests the collapse, but it weakly dissipates the atoms. The
confining trap then reforms the condensate at later times. In contrast, 2D
condensates undergo a {\it strong collapse}: The atoms stay mainly located at
center and recombination sequentially absorbs a significant amount of
particles.

</DOC>
<DOC>
<DOCNO> 169956 </DOCNO>
Ground state laser cooling using electromagnetically induced


  A laser cooling method for trapped atoms is described which achieves ground
state cooling by exploiting quantum interference in a driven Lambda-shaped
arrangement of atomic levels. The scheme is technically simpler than existing
methods of sideband cooling, yet it can be significantly more efficient, in
particular when several motional modes are involved, and it does not impose
restrictions on the transition linewidth. We study the full quantum mechanical
model of the cooling process for one motional degree of freedom and show that a
rate equation provides a good approximation.

</DOC>
<DOC>
<DOCNO> 117691 </DOCNO>
One-Point Probability Distribution Functions of Supersonic Turbulent


  Turbulence is essential for understanding the structure and dynamics of
molecular clouds and star-forming regions. There is a need for adequate tools
to describe and characterize the properties of turbulent flows. One-point
probability distribution functions (pdf's) of dynamical variables have been
suggested as appropriate statistical measures and applied to several observed
molecular clouds. However, the interpretation of these data requires comparison
with numerical simulations. To address this issue, SPH simulations of driven
and decaying, supersonic, turbulent flows with and without self-gravity are
presented. In addition, random Gaussian velocity fields are analyzed to
estimate the influence of variance effects. To characterize the flow
properties, the pdf's of the density, of the line-of-sight velocity centroids,
and of the line centroid increments are studied. This is supplemented by a
discussion of the dispersion and the kurtosis of the increment pdf's, as well
as the spatial distribution of velocity increments for small spatial lags. From
the comparison between different models of interstellar turbulence, it follows
that the inclusion of self-gravity leads to better agreement with the observed
pdf's in molecular clouds. The increment pdf's for small spatial lags become
exponential for all considered velocities. However, all the processes
considered here lead to non-Gaussian signatures, differences are only gradual,
and the analyzed pdf's are in addition projection dependent. It appears
therefore very difficult to distinguish between different physical processes on
the basis of pdf's only, which limits their applicability for adequately
characterizing interstellar turbulence.

</DOC>
<DOC>
<DOCNO> 174610 </DOCNO>
Title: Localized Charged-Neutral Fluctuations in 158 A GeV Pb+Pb


  First results on the measurement of localized fluctuations in the
multiplicity of charged particles and photons produced in central 158 A GeV
Pb+Pb collisions are presented. The charged versus neutral correlations in
common phase space regions of varying azimuthal size are analyzed by two
different methods. The measured results are compared to those from simulations
and to those from different types of mixed events. The comparison indicates the
presence of non-statistical fluctuations in both charged particle and photon
multiplicities in limited azimuthal regions. However, no correlated
charge-neutral fluctuations are observed.

</DOC>
<DOC>
<DOCNO> 101688 </DOCNO>
Gradient flows of closed 1-forms and their closed orbits


  We consider the closed orbit structure of generic gradient flows of Morse
closed 1-forms. The torsion of a chain homotopy equivalence between the Novikov
complex and the completed simplicial chain complex of the universal cover
detects the eta function of the flow. We extend this result to arbitrary Morse
closed 1-forms. The case of rational forms was considered by A. Pajitnov.

</DOC>
<DOC>
<DOCNO> 84990 </DOCNO>
Quasi-normal modes of AdS black holes : A superpotential approach


  A novel method, based on superpotentials is proposed for obtaining the
quasi-normal modes of anti-de Sitter black holes. This is inspired by the case
of the three-dimensional BTZ black hole, where the quasi-normal modes can be
obtained exactly and are proportional to the surface gravity. Using this
approach, the quasi-normal modes of the five dimensional Schwarzschild
anti-deSitter black hole are computed numerically. The modes again seem to be
proportional to the surface gravity for very small and very large black holes.
They reflect the well-known instability of small black holes in anti-deSitter
space.

</DOC>
<DOC>
<DOCNO> 121075 </DOCNO>
The Chemical Compositions of the SRd Variable Stars. III. KK Aquilae, AG


  Chemical compositions are derived from high-resolution spectra for five field
SRd variables. These supergiants not previously analysed are shown to be
metal-poor: KK Aql with [Fe/H] = -1.2, AG Aur with [Fe/H] = -1.8, Z Aur with
[Fe/H] = -1.4, W LMi with [Fe/H] = -1.1, and WW Tau with [Fe/H] = -1.1. Their
compositions are, except for two anomalies, identical to within the measurement
errors with the compositions of subdwarfs, subgiants, and less evolved giants
of the same [Fe/H]. One anomaly is an s-process enrichment for KK Aql, the
first such enrichment reported for a SRd variable. The second and more
remarkable anomaly is a strong lithium enrichment for W LMi, also a first for
field SRds. The Li I 6707 A profile is not simply that of a photospheric line
but includes strong absorption from red-shifted gas, suggesting, perhaps, that
lithium enrichment results from accretion of Li-rich gas. This potential clue
to lithium enrichment is discussed in light of various proposals for lithium
synthesis in evolved stars.

</DOC>
<DOC>
<DOCNO> 39636 </DOCNO>
Bose-Einstein correlations in charged kaon pairs from Z0 decays into two


  Bose-Einstein correlations in pairs of charged kaons produced in a sample of
3.9 million hadronic Z0 decays have been measured with the OPAL experiment at
LEP. Charged kaons were identified in the central tracking detector using their
specific energy loss in the drift chamber gas. The correlation function was
studied in two-jet events using a double ratio, formed by the number of
like-sign pairs normalised by a reference sample in the data, divided by the
same ratio in a Monte Carlo simulation. The enhancement at small values of the
four-momentum difference of the pair was parametrised using a Gaussian
function. The parameters of the Bose-Einstein correlations were measured to be
lambda = 0.82+-0.22(+0.17,-0.12) for the strength and R0 =
0.56+-0.08(+0.08,-0.06) fm for the kaon source radius, where the first errors
are statistical and the second systematic. Corrections for final-state
interactions are discussed.

</DOC>
<DOC>
<DOCNO> 10796 </DOCNO>
Dynamical mean-field study of ferromagnetism in the periodic Anderson


  The ferromagnetic phase diagram of the periodic Anderson model is calculated
using dynamical mean-field theory in combination with the modified perturbation
theory. Concentrating on the intermediate valence regime, the phase boundaries
are established as function of the total electron density, the position of the
atomic level and the hybridization strength. The main contribution to the
magnetic moment stems from the f-electrons. The conduction band polarization
is, depending on the system parameters either parallel or antiparallel to the
f-magnetization. By investigating the densities of states, one observes that
the change of sign of the conduction band polarization is closely connected to
the hybridization gap, which is only apparent in the case of almost complete
polarization of the f-electrons. Finite-temperature calculations are also
performed, the Curie temperature as function of electron density and f-level
position are determined. In the intermediate-valence regime, the phase
transitions are found to be of second order.

</DOC>
<DOC>
<DOCNO> 118100 </DOCNO>
Clustering of mass and galaxies


  These lectures cover various aspects of the statistical description of
cosmological density fields. Observationally, this consists of the point
process defined by galaxies, and the challenge is to relate this to the
continuous density field generated by gravitational instability in dark matter.
The main topics discussed are (1) nonlinear structure in CDM models; (2)
statistical measures of clustering; (3) redshift-space distortions; (4)
small-scale clustering and bias. The overall message is optimistic, in that
simple assumptions for where galaxies should form in the mass density field
allow one to understand the systematic differences between galaxy data and the
predictions of CDM models.

</DOC>
<DOC>
<DOCNO> 170372 </DOCNO>
An Intutive Paragidm for Quantum Mechanics


  Use is made of a relativistic kinematic modulation effect to compliment
imagery from Stochastic Electrodynamics to provide intuitive paradigms for
Quantum Mechanics. Based on these paradigms, resolutions for epistemological
problems vexing conventional interpretations of Quantum Mechanics are proposed
and discussed.

</DOC>
<DOC>
<DOCNO> 68676 </DOCNO>
Nonequilibrium evolution and symmetry structure of the large-N $\Phi^4$


  We consider the large-N $\Phi^4$ theory with spontaneously broken symmetry at
finite temperature. We study, in the large-N limit, quantum states which are
characterized by a time dependent, spatially homogenous expectation value of
one of the field components, $\phi_N(t)$, and by quantum fluctuations of the
other $N-1$ components, that evolve in the background of the classical field.
Investigating such systems out of equilibrium has recently been shown to
display several interesting features. We extend here this type of
investigations to finite temperature systems. Essentially the novel features
observed at T=0 carry over to finite temperature. This is not unexpected, as
the main mechanisms that determine the late-time behavior remain the same. We
extend two empirical - presumably exact - relations for the late-time behavior
to finite temperature and use them to define the boundaries between the region
of different asymptotic regimes. This results in a phase diagram with the
temperature and the initial value of the classical field as parameters, the
phases being characterized by spontaneous symmetry breaking resp. symmetry
restoration. The time evolution is computed numerically and agrees very well
with the expectations.

</DOC>
<DOC>
<DOCNO> 9445 </DOCNO>
Vector lattice model for stresses in granular materials


  A vector lattice model for stresses in granular materials is proposed. A two
dimensional pile built by pouring from a point is constructed numerically
according to this model. Remarkably, the pile violates the Mohr Coulomb
stability criterion for granular matter, probably because of the inherent
anisotropy of such poured piles. The numerical results are also compared to the
earlier continuum FPA model and the (scalar) lattice $q$-model.

</DOC>
<DOC>
<DOCNO> 121207 </DOCNO>
Models for Multiband IR Surveys


  Empirical 'backward' galaxy evolution models for IR-bright galaxies are
constrained using multiband IR surveys. A new Monte-Carlo algorithm is
developed for this task. It exploits a large library of realistic Spectral
Energy Distributions (SEDs) of 837 local IR galaxies (IRAS 25$\mu m$ selected)
from the UV (1000{\AA}) to the radio (20cm), including ISO-measured 3--13$\mu
m$ unidentified broad features (UIBs). The basic assumption is that the local
correlation between SEDs and Mid-Infrared (MIR) luminosities can be applied to
earlier epochs of the Universe. Three populations of IR sources are considered
in the evolution models. These include (1) starburst galaxies, (2) normal
late-type galaxies, and (3) galaxies with AGN. A set of models so constructed
are compared with data from the literature. Predictions for number counts,
confusion limits, redshift distributions, and color-color diagrams are made for
multiband surveys using the upcoming SIRTF satellite.

</DOC>
<DOC>
<DOCNO> 13174 </DOCNO>
Simulations of Bose fields at finite temperature


  We introduce a time-dependent projected Gross-Pitaevskii equation to describe
a partially condensed homogeneous Bose gas, and find that this equation will
evolve randomised initial wave functions to equilibrium. We compare our
numerical data to the predictions of a gapless, second order theory of
Bose-Einstein condensation [S. A. Morgan, J. Phys. B {\bf 33}, 3847 (2000)],
and find that we can determine a temperature when the theory is valid. As the
Gross-Pitaevskii equation is non-perturbative, we expect that it can describe
the correct thermal behaviour of a Bose gas as long as all relevant modes are
highly occupied. Our method could be applied to other boson fields.

</DOC>
<DOC>
<DOCNO> 119182 </DOCNO>
Cosmological models from quintessence


  A generalized quintessence model is presented which corresponds to a richer
vacuum structure that, besides a time-dependent, slowly varying scalar field,
contains a varying cosmological term. From first principles we determine a
number of scalar-field potentials that satisfy the constraints imposed by the
field equations and conservations laws, both in the conventional and
generalized quintessence models. Besides inverse-power law solutions, these
potentials are given in terms of hyperbolic functions or the twelve Jacobian
elliptic functions, and are all related to the luminosity distance by means of
an integral equation. Integration of this equation for the different solutions
leads to a large family of cosmological models characterized by luminosity
distance-redshift relations. Out of such models, only four appear to be able to
predict a required accelerating universe conforming to observations on
supernova Ia, at large or moderate redshifts.

</DOC>
<DOC>
<DOCNO> 179039 </DOCNO>
Evaluation of cluster expansions and correlated one-body properties of


  Three different cluster expansions for the evaluation of correlated one-body
properties of s-p and s-d shell nuclei are compared. Harmonic oscillator wave
functions and Jastrow type correlations are used, while analytical expressions
are obtained for the charge form factor, density distribution, and momentum
distribution by truncating the expansions and using a standard Jastrow
correlation function f. The harmonic oscillator parameter b and the correlation
parameter \beta have been determined by a least-squares fit to the experimental
charge form factors in each case. The information entropy of nuclei in
position-space (S_r) and momentum-space (S_k) according to the three methods
are also calculated. It is found that the larger the entropy sum S=S_r+S_k (the
information content of the system) the smaller the values of \chi^2. This
indicates that S is a criterion of the quality of a given nuclear model,
according to the maximum entropy principle. Only two exceptions to this rule,
out of many cases examined, were found. Finally an analytic expression for the
so-called "healing" or "wound" integrals is derived with the function f
considered, for any state of the relative two-nucleon motion and their values
in certain cases are computed and compared.

</DOC>
<DOC>
<DOCNO> 40177 </DOCNO>
Measurement of $\psi(2S)$ decays to baryon pairs


  A sample of 3.95M $\psi(2S)$ decays registered in the BES detector are used
to study final states containing pairs of octet and decuplet baryons. We report
branching fractions for $\psi(2S)\to p\bar{p}$, $\Lambda\bar{\Lambda}$,
$\Sigma^0\bar{\Sigma}{}^0$, $\Xi^-\bar{\Xi}{}^+$,
$\Delta^{++}\bar{\Delta}{}^{--}$, $\Sigma^+(1385)\bar{\Sigma}{}^-(1385)$,
$\Xi^0(1530)\bar{\Xi}{}^0(1530)$, and $\Omega^-\bar{\Omega}{}^+$. These results
are compared to expectations based on the SU(3)-flavor symmetry, factorization,
and perturbative QCD.

</DOC>
<DOC>
<DOCNO> 121684 </DOCNO>
Non-spherical core collapse supernovae and nucleosynthesis


  Motivated by observations of supernova SN 1987A, various authors have
simulated Rayleigh-Taylor (RT) instabilities in the envelopes of core collapse
supernovae (for a review, see Mueller 1998). The non-radial motion found in
these simulations qualitatively agreed with observations in SN 1987A, but
failed to explain the extent of mixing of newly synthesized 56Ni
quantitatively. Here we present results of a 2D hydrodynamic simulation which
re-addresses this failure and covers the entire evolution of the first 5 hours
after core bounce.

</DOC>
<DOC>
<DOCNO> 123225 </DOCNO>
Asymmetry in Isolated, Morphologically Normal Sa Galaxies


  We have examined the morphological and dynamical HI symmetry properties of a
sample of moderately inclined Sa galaxies which are classified as
morphologically normal. The sample galaxies were known a prior to exhibit
kinematic peculiarities ranging from warps to independent, wholly decoupled
disks, and are possibly the remnants of minor mergers. We compare the asymmetry
of the rotation curves to global kinematic asymmetry, and find a relationship
between rotation curve asymmetry and the kinematic n=2 mode. We have also
examined the kinematics of these galaxies following the discussion of Briggs
(1990) and find that the warps observed in the HI disks of these galaxies
deviate significantly from the simple rules for warps that commonly apply.

</DOC>
<DOC>
<DOCNO> 8758 </DOCNO>
Thermodynamics of the bilinear-biquadratic spin one Heisenberg chain


  The magnetic susceptibility and specific heat of the one-dimensional S=1
bilinear-biquadratic Heisenberg model are calculated using the transfer matrix
renormalization group. By comparing the results with the experimental data of
${\rm LiVGe_2O_6}$ measured by Millet et al. (Phys. Rev. Lett. {\bf 83}, 4176
(1999)), we find that the susceptibility data of this material, after
subtracting the impurity contribution, can be quantitatively explained with
this model. The biquadratic exchange interaction in this material is found to
be ferromagnetic, i.e. with a positive coupling constant.

</DOC>
<DOC>
<DOCNO> 116701 </DOCNO>
Finite-Difference Calculations for Atoms and Diatomic Molecules in


  Fully numerical mesh solutions of 2D quantum equations of Schroedinger and
Hartree-Fock type allow us to work with wavefunctions which possess a very
flexible geometry. This flexibility is especially important for calculations of
atoms and molecules in strong external fields where neither the external field
nor the internal interactions can be considered as a perturbation. The
applications of the present approach include calculations of atoms and diatomic
molecules in strong static electric and magnetic fields. For the latter we have
carried out Hartree-Fock calculations for He, Li, C and several other atoms.
This yields in particular the first comprehensive investigation of the ground
state configurations of the Li and C atoms in the whole range of magnetic
fields (0<B<10000 a.u.) and a study of the ground state electronic
configurations of all the atoms with 1<Z<11 and their ions A^+ in the
high-field fully spin-polarised regime. The results in a case of a strong
electric field relate to single-electron systems including the correct solution
of the Schroedinger equation for the H_2^+ ion (energies and decay rates) and
the hydrogen atom in strong parallel electric and magnetic fields.

</DOC>
<DOC>
<DOCNO> 39611 </DOCNO>
The Parameterized Simulation of Electromagnetic Showers in Homogeneous


  A general approach to a fast simulation of electromagnetic showers using
parameterizations of the longitudinal and radial profiles in homogeneous and
sampling calorimeters is described. The dependence of the shower development on
the materials used and the sampling geometry is taken into account explicitly.
Comparisons with detailed simulations of various calorimeters and with data
from the liquid argon calorimeter of the H1 experiment are made.

</DOC>
<DOC>
<DOCNO> 70865 </DOCNO>
Flavor Symmetry and Neutrino Oscillations


  We show how the nearly bi-maximal mixing scenario comes out naturally from
gauged $SO(3)_{F}$ flavor symmetry via spontaneous symmetry breaking. An
interesting relation between the neutrino mass-squared differences and the
mixing angle, i.e., $\Delta m_{\mu e}^2 / \Delta m_{\tau\mu}^2 \simeq 2|U_{e
3}|^2 $ is obtained. The smallness of the ratio (or $|U_{e 3}|$) can also
naturally be understood from an approximate permutation symmetry. Once the
mixing element $|U_{e 3}|$ is determined, such a relation will tell us which
solution will be favored within this model. The model can also lead to
interesting phenomena on lepton-flavor violations.

</DOC>
<DOC>
<DOCNO> 84294 </DOCNO>
Locating Boosted Kerr and Schwarzschild Apparent Horizons


  We describe a finite-difference method for locating apparent horizons and
illustrate its capabilities on boosted Kerr and Schwarzschild black holes. Our
model spacetime is given by the Kerr-Schild metric. We apply a Lorentz boost to
this spacetime metric and then carry out a 3+1 decomposition. The result is a
slicing of Kerr/Schwarzschild in which the black hole is propagated and Lorentz
contracted. We show that our method can locate distorted apparent horizons
efficiently and accurately.

</DOC>
<DOC>
<DOCNO> 13172 </DOCNO>
A nanomechanical resonator shuttling single electrons at radio


  We observe transport of electrons through a metallic island on the tip of a
nanomechanical pendulum. The resulting tunneling current shows distinct
features corresponding to the discrete mechanical eigenfrequencies of the
pendulum. We report on measurements covering the temperature range from 300 K
down to 4.2 K. We explain the I-V curve, which differs from previous
theoretical predictions, with model calculations based on a Master equation
approach.

</DOC>
<DOC>
<DOCNO> 100538 </DOCNO>
Isospectral deformations of metrics on spheres


  We construct non-trivial continuous isospectral deformations of Riemannian
metrics on the ball and on the sphere in $\R^n$ for every $n\geq 9$. The
metrics on the sphere can be chosen arbitrarily close to the round metric; in
particular, they can be chosen to be positively curved. The metrics on the ball
are both Dirichlet and Neumann isospectral and can be chosen arbitrarily close
to the flat metric.

</DOC>
<DOC>
<DOCNO> 122808 </DOCNO>
Relativistic magnetospheres of rotating cosmic objects - the regime of


  Selfconsistent magnetospheres of rotating cosmic magnets with arbitrary
inclination of the magnetic against the rotational axis are considered. Present
studies concentrate on the regime dominated by the force--free surface (FFS). A
classical macroscopic fluid description is applied and radiation reaction is
taken into account. As in earlier work of our group, a 'standard set of
parameters' is used. Under these conditions, the following features are found
among other results: global charge separation exists for all degrees of
inclination of the magnetic against the rotational axis; clouds of different
charge are seperated by regions of vanishing particle number density; as
expected, test particles inserted into the latter regionspropagate into one of
the adjacent clouds. Strong polodial currents exist; locally averaged particle
energies typically range up to 10^16 - 10^17 eV, depending on the angle of
inclination.

</DOC>
<DOC>
<DOCNO> 102043 </DOCNO>
Frames in Hilbert C*-modules and C*-algebras


  We present a general approach to a modular frame theory in C*-algebras and
Hilbert C*-modules. The investigations rely on the idea of geometric dilation
to standard Hilbert C*-modules over unital C*-algebras that possess orthonormal
Hilbert bases, and of reconstruction of the frames by projections and by other
bounded modular operators with suitable ranges. We obtain frame representations
and decomposition theorems, as well as similarity and equivalence results for
frames. Hilbert space frames and quasi-bases for conditional expectations of
finite index on C*-algebras appear as special cases. Using a canonical
categorical equivalence of Hilbert C*-modules over commutative C*-algebras and
(F)Hilbert bundles the results find a reintepretation for frames in vector and
(F)Hilbert bundles. Fields of applications are investigations on
Cuntz-Krieger-Pimsner algebras, on conditional expectations of finite index, on
various ranks of C*-algebras, on classical frame theory of Hilbert spaces
(wavelet and Gabor frames), and others. 2001: In the introduction we refer to
related publications in detail.

</DOC>
<DOC>
<DOCNO> 8571 </DOCNO>
Identification of clusters of companies in stock indices via Potts


  The clustering of companies within a specific stock market index is studied
by means of super-paramagnetic transitions of an appropriate q-state Potts
model where the spins correspond to companies and the interactions are
functions of the correlation coefficients determined from the time dependence
of the companies' individual stock prices. The method is a generalization of
the clustering algorithm by Domany et. al. to the case of anti-ferromagnetic
interactions corresponding to anti-correlations. For the Dow Jones Industrial
Average where no anti-correlations were observed in the investigated time
period, the previous results obtained by different tools were well reproduced.
For the Standard & Poor's 500, where anti-correlations occur, repulsion between
stocks modify the cluster structure.

</DOC>
<DOC>
<DOCNO> 121955 </DOCNO>
Type Ia supernovae: differences due to progenitors within delayed


  At this moment, the use of SNIa for cosmology lies on the assumption that the
SNe at high redshifts are equal to the local ones. However, some observations
indicate a correlation between the light curve (LC) properties and the
morphological type of the host galaxy. This could indicate a dependence with
the age (mass/composition) of the underlying population. In this work we have
chosen the delayed detonation explosion model in CO Chandrasekhar mass WDs to
explore the dependence of the SNIa LC and nucleosynthesis with the initial mass
and composition of the WD progenitor. The progenitor influences the final SNIa
via the mass of the CO core formed and the C/O ratio within it (1D explosion
models). We have followed the evolution of stars with masses between 1.5 and 8
Mo and metallicity, Z=0, 1.E-05, 0.001 and 0.02, from the pre-main sequence to
the TP-AGB phase. The differences obtained in the final C/O ratio within the
explosive WD are smaller than 22%. This results in a difference at maximum of
0.03 mag and of 0.1 mag when the brightness-decline relation is applied.

</DOC>
<DOC>
<DOCNO> 8222 </DOCNO>
On the influence of gravity on the thermal conductivity


  In this paper we evaluate the corrections to the Navier-Stokes constitutive
equations induced by the action of a gravitational field in a gas subjected to
a thermal gradient parallel to the field with no convection. The analysis is
performed from an exact perturbation solution of the BGK kinetic model for
Maxwell molecules through sixth order in the field. The reference state (zeroth
order approximation) corresponds to the exact solution in the pure planar
Fourier flow, which holds for arbitrary values of the thermal gradient. The
results show that the pressure tensor becomes anisotropic, so that the momentum
flux along the field direction is enhanced. In addition, the heat flux
increases (decreases) with respect to its Navier-Stokes value when the gas is
heated from above (below).

</DOC>
<DOC>
<DOCNO> 9009 </DOCNO>
Collective Modes in Strongly Coupled Elecronic Bilayer Liquids


  We present the first reliable calculation of the collective mode structure of
a strongly coupled electronic bilayer. The calculation is based on a classical
model through the $3^{rd}$ frequency-moment-sum-rule preserving Quasi Localized
Charge Approximation, using the recently calculated Hypernetted Chain pair
correlation functions. The spectrum shows an energy gap at $k=0$ and the
absence of a previously conjectured dynamical instability.

</DOC>
<DOC>
<DOCNO> 40356 </DOCNO>
Energy calibration of large underwater detectors using stopping muons


  We propose to use stopping cosmic-ray muons in the energy calibration of
planned and deployed large underwater detectors. The method is based on the
proportionality between the incident muon energy and the length of the muon
path before it stops. Simultaneous measurements of the muon path and the
amplitude of the signal from the photomultiplier tubes allow a relation between
the energy deposited in the sensitive volume of the detector and the observed
signal to be derived, and also provide a test of detector simulations. We
describe the proposed method and present the results of simulations.

</DOC>
<DOC>
<DOCNO> 122628 </DOCNO>
Structure of the Galactic Stellar Halo Prior to Disk Formation


  We develop a method for recovering the global density distribution of the
ancient Galactic stellar halo prior to disk formation, based on the present
orbits of metal-poor stars observed in the solar neighborhood. The method
relies on the adiabatic invariance of the action integrals of motion for the
halo population during the slow accumulation of a disk component, subsequent to
earlier halo formation. The method is then applied to a sample of local stars
with [Fe/H]<=-1.5, likely to be dominated by the halo component, taken from
Beers et al.'s recently revised and supplemented catalog of metal-poor stars
selected without kinematic bias. We find that even if the Galactic potential is
made spherical by removing the disk component in an adiabatic manner, the halo
density distribution in the inner halo region (R <= 15 kpc) remains moderately
flattened, with axial ratio of about 0.8 for stars in the abundance range
[Fe/H]<=-1.8 and about 0.7 for the more metal-rich interval -1.8<[Fe/H]<=-1.5.
The outer halo remains spherical for both abundance intervals. We also find
that this initial flattening of the inner halo is caused by the anisotropic
velocity dispersions of the halo stars. These results suggest that the
two-component nature of the present-day stellar halo, characterized by a highly
flattened inner halo and nearly spherical outer halo, is a consequence of both
an initially two-component density distribution of the halo (perhaps a
signature of dissipative halo formation) and of the adiabatic flattening of the
inner part by later disk formation. Further implications of our results for the
formation of the Galaxy are also discussed, in particular in the context of the
hierarchical clustering scenario of galaxy formation.

</DOC>
<DOC>
<DOCNO> 122874 </DOCNO>
One-dimensional Electric Field Structure of an Outer Gap Accelerator -


  We investigate a stationary particle acceleration zone in the outer
magnetosphere of a spinning neutron star. The charge depletion due to a global
current causes a large electric field along the magnetic field lines. Migratory
electrons and/or positrons are accelerated by this field to radiate curvature
gamma-rays, some of which collide with the X-rays to materialize as pairs in
the gap. As a result of this pair-production cascade, the replenished charges
partially screen the electric field, which is self-consistently solved together
with the distribution of particles and gamma-rays. If no current is injected at
neither of the boundaries of the accelerator, the gap is located around the
so-called null surface, where the local Goldreich-Julian charge density
vanishes. However, we find that the gap position shifts outwards (or inwards)
when particles are injected at the inner (or outer) boundary. We apply the
theory to the nine pulsars of which X-ray fields are known from observations.
We show that the gap should be located near to or outside of the null surface
for the Vela pulsar and PSR B1951+32, so that their expected GeV spectrum may
be consistent with observations. We then demonstrate that the intrinsically
large TeV flux from the outer gap of PSR B0540-69 is absorbed by the
magnetospheric infrared photons to be undetectable. We also point out that the
electrodynamic structure and the resultant GeV emission properties of
millisecond pulsars are similar to young pulsars.

</DOC>
<DOC>
<DOCNO> 9483 </DOCNO>
Optical Absorption of an Interacting Many-Polaron Gas


  The optical absorption of a many (continuum) polaron gas is derived in the
framework of a variational approach at zero temperature and weak or
intermediate electron-phonon coupling strength. We derive a compact formula for
the optical conductivity of the many-polaron system taking into account
many-body effects in the electron or hole system. Within the method presented
here, these effects are contained completely in the dynamical structure factor
of the electron or hole system. This allows to build on well-established
studies of the interacting electron gas. Based on this approach a novel feature
in the absorption spectrum of the many-polaron gas, related to the emission of
a plasmon together with a phonon, is identified. As an application and
illustration of the technique, we compare the theoretical many-polaron optical
absorption spectrum as derived in the present work with the `d-band' absorption
feature in Nd$_{2}$CuO$_{2}$. Similarities are shown between the theoretically
and the experimentally derived first frequency moment of the optical absorption
of a family of differently doped Nd$_{2-x}$Ce$_{x}$CuO$_{4-y}$ materials.

</DOC>
<DOC>
<DOCNO> 10850 </DOCNO>
Stabilization/destabilization of cell membranes by multivalent ions:


  We propose a mechanism for the stabilization/destabilization of cell
membranes by multivalent ions with an emphasis on its implications for the
division and fusion of cells. We find that multivalent cations preferentially
adsorbed onto a membrane dramatically changes the membrane stability. They not
only reduce the surface charge density of the membrane but also induce a
repulsive barrier to pore growth. While both of these effects lead to enhanced
membrane stability against vesiculation and pore growth, the repulsive barrier
arises from correlated fluctuations of the adsorbed cations and favors closure
of a pore. Finally, the addition of a small amount of multivalent anions can
reverse the membrane stabilization, providing an effective way to regulate
membrane stability.

</DOC>
<DOC>
<DOCNO> 119048 </DOCNO>
Formation and evolution of dusty starburst galaxies I. A new method for


  We present a new numerical code which is designed to derive a spectral energy
distribution (SED) for an arbitrary spatial distribution of stellar and gaseous
components in a dusty starburst galaxy. We apply a ray tracing method to
numerical simulations and thereby estimate extinction and reemission of stellar
light by dusty gas in an explicitly self-consistent manner. By using this code,
we can investigate simultaneously dynamical and photometric evolution of a
dusty galaxy based on stellar and gaseous dynamical simulations. As an example,
we demonstrate when and how a major galaxy merger with dusty starburst becomes
an ultra-luminous infrared galaxy owing to strong internal dust extinction. We
furthermore discuss advantages and disadvantages of the present new code in
clarifying the nature and the origin of low and high redshift dusty starburst
galaxies.

</DOC>
<DOC>
<DOCNO> 121866 </DOCNO>
Evidence for Rapid Iron K_alpha Line Flux Variability in MCG--6-30-15


  This paper employs direct spectral fitting of individual orbital data in
order to measure rapid X-ray iron K_alpha line and continuum spectral slope
variations in Seyfert 1 galaxies with unprecedented temporal resolution.
Application of this technique to a long RXTE observation of MCG--6-30-15
indicates that the line flux does vary on short (~1d) timescales, but that
these variations are not correlated with changes in the continuum flux or
slope. These rapid variations indicate that the line does indeed originate
close to the black hole, confirming predictions based on its very broad
profile. However, the lack of a correlation with the continuum presents
problems for models in which the line variations are driven by those in the
continuum, modified only by light-travel time effects. Instead, it may be that
the line responds according to a physical process with a different time scale,
such as ionization instabilities in the disk, or perhaps that the geometry and
physical picture is more complex than implied by the simplest disk-corona
models.
  These data also indicate that the slope of the underlying power-law continuum
(Gamma) shows strong variability and is tightly correlated with the continuum
flux in the sense that the spectrum steepens as the source brightens. All of
these results have been checked with extensive simulations, which also
indicated that a spurious correlation between Gamma and Compton reflection
fraction (R) will result if these quantities are measured from the same
spectra. This casts serious doubts on previous claims of such a Gamma-R
correlation.

</DOC>
<DOC>
<DOCNO> 10695 </DOCNO>
Freezing of dynamical exponents in low dimensional random media


  A particle in a random potential with logarithmic correlations in dimensions
$d=1,2$ is shown to undergo a dynamical transition at $T_{dyn}>0$. In $d=1$
exact results demonstrate that $T_{dyn}=T_c$, the static glass transition
temperature, and that the dynamical exponent changes from $z(T)=2 + 2
(T_c/T)^2$ at high temperature to $z(T)= 4 T_c/T$ in the glass phase. The same
formulae are argued to hold in $d=2$. Dynamical freezing is also predicted in
the 2D random gauge XY model and related systems. In $d=1$ a mapping between
dynamics and statics is unveiled and freezing involves barriers as well as
valleys. Anomalous scaling occurs in the creep dynamics.

</DOC>
<DOC>
<DOCNO> 101356 </DOCNO>
General energy bounds for systems of bosons with soft cores


  We study a bound system of N identical bosons interacting by model pair
potentials of the form V(r) = A sgn(p)r^p + B/r^2, A > 0, B >= 0. By using a
variational trial function and the `equivalent 2-body method', we find explicit
upper and lower bound formulas for the N-particle ground-state energy in
arbitrary spatial dimensions d > 2 for the two cases p = 2 and p = -1. It is
demonstrated that the upper bound can be systematically improved with the aid
of a special large-N limit in collective field theory.

</DOC>
<DOC>
<DOCNO> 119449 </DOCNO>
An X-ray burst with strong photospheric radius expansion observed from


  We present results of the RXTE observations of an extremely intense X-ray
burst detected from the source 4U1724-307 in the globular cluster Terzan 2. The
burst profile was complex consisting of two precursors and a long primary peak.
During the first (strong) precursor the source luminosity, L ~ 3.6 x 10^38
erg/s, was comparable with that measured in the main event. The structure of
the profile, its dependence on energy and observed spectral evolution indicated
strong photospheric expansion of a neutron star. The effective temperature and
radius of the photosphere were estimated from the black body model at different
stages of expansion, their correlations and specific features of the profile
were analyzed and discussed.

</DOC>
<DOC>
<DOCNO> 178844 </DOCNO>
Two-neutron separation energies, binding energies and phase transitions


  In the framework of the interacting boson model the three transitional
regions (rotational-vibrational, rotational-$\gamma$-unstable and,
vibrational-$\gamma$-unstable transitions) are reanalyzed. A new kind of plot
is presented for studying phase transitions in finite systems such as atomic
nuclei. The importance of analyzing binding energies and not only energy
spectra and electromagnetic transitions, describing transitional regions is
emphasized. We finally discuss a number of realistic examples.

</DOC>
<DOC>
<DOCNO> 39774 </DOCNO>
Uncertainties due to imperfect knowledge of systematic effects: general


  Starting from considerations about meaning and subsequent use of asymmetric
uncertainty intervals of experimental results, we review the issue of
uncertainty propagation. We show that, using a probabilistic approach (the
so-called Bayesian approach), all sources of uncertainty can be included in a
logically consistent way. Practical formulae for the first moments of the
probability distribution are derived up to second-order approximations.

</DOC>
<DOC>
<DOCNO> 117515 </DOCNO>
Physical morphology and triggers of starburst galaxies


  We present a method of determining the likely triggering mechanisms for
luminous, nearby starbursts based on their optical asymmetry and (B-V) color --
what we term as indices of `physical morphology.' By comparing the starbursts'
locations in a color-asymmetry diagram to an independent, nearby galaxy sample,
we identify which starbursts are likely triggered by an interaction/merger. We
confirm our morphological interpretation based on a comparison to 20% and 50%
HI velocity-width ratios. We further explain how this use of physical
morphology can put constraints on the dynamical history of other galaxies,
including star-forming galaxies at high redshifts.

</DOC>
<DOC>
<DOCNO> 84195 </DOCNO>
Ricci Collineations of the Bianchi Type II, VIII, and IX Space-times


  Ricci and contracted Ricci collineations of the Bianchi type II, VIII, and IX
space-times, associated with the vector fields of the form (i) one component of
$\xi^a(x^b)$ is different from zero and (ii) two components of $\xi^a(x^b)$ are
different from zero, for $a,b=1,2,3,4$, are presented. In subcase (i.b), which
is $\xi^a= (0,\xi^2(x^a),0,0)$, some known solutions are found, and in subcase
(i.d), which is $\xi^a =(0,0,0,\xi^4(x^a))$, choosing $S(t)=const.\times R(t)$,
the Bianchi type II, VIII, and IX space-times is reduced to the
Robertson-Walker metric.

</DOC>
<DOC>
<DOCNO> 71755 </DOCNO>
On dependence of nonperturbative contributions in $\bar\alpha_s(q^2)$ on


  In the framework of analytic approach to QCD, which has been recently
intensively developed, the dependence of nonperturbative contributions in a
running coupling of strong interaction on initial perturbative approximation to
3-loop order is studied. The nonperturbative contributions are obtained in an
explicit form. In the ultraviolet region they are shown to be represented in
the form of the expansion in the inverse powers of Euclidean momentum squared.
The expansion coefficients are calculated for different numbers of active quark
flavors $n_f$ and for different numbers of loops taken into account. For all
$n_f$ of interest it is shown that 2-loop order and 3-loop order corrections
result in partial compensation of 1-loop order leading in the ultraviolet
region nonperturbative contribution.

</DOC>
<DOC>
<DOCNO> 69724 </DOCNO>
New Production Mechanism of Neutral Higgs Bosons with Right scalar tau


  Motived by the neutrino oscillation data, we consider the lightest tau
sneutrino $\tilde \nu_{\tau_1}$ (which is mostly the right tau sneutrino) to be
the lightest supersymmetric particle (LSP) in the framework of the minimal
supersymmetric Standard Model. Both the standard and the non-standard trilinear
scalar coupling terms are included for the right tau sneutrino interactions.
The decay branching ratio of $\tilde \nu_{\tau_2} \to \tilde \nu_{\tau_1}+ h^0$
can become so large that the production rate of the lightest neutral Higgs
boson ($h^0$) can be largely enhanced at electron or hadron colliders, either
from the direct production of $\tilde \nu_{\tau_2}$ or from the decay of
charginos, neutralinos, sleptons, and the cascade decay of squarks and gluinos,
etc. Furthermore, because of the small LSP annihilation rate, $\tilde
\nu_{\tau_1}$ can be a good candidate for cold dark matter.

</DOC>
<DOC>
<DOCNO> 99609 </DOCNO>
A categorification of the Temperley-Lieb algebra and Schur quotients of


  We identify the Grothendieck group of certain direct sum of singular blocks
of the highest weight category for sl(n) with the n-th tensor power of the
fundamental (two-dimensional) sl(2)-module. The action of U(sl(2)) is given by
projective functors and the commuting action of the Temperley-Lieb algebra by
Zuckerman functors. Indecomposable projective functors correspond to Lusztig
canonical basis in U(sl(2)). In the dual realization the n-th tensor power of
the fundamental representation is identified with a direct sum of parabolic
blocks of the highest weight category. Translation across the wall functors act
as generators of the Temperley-Lieb algebra while Zuckerman functors act as
generators of U(sl(2)).

</DOC>
<DOC>
<DOCNO> 118661 </DOCNO>
2.5-11 micron spectroscopy and imaging of AGNs: implication for


  We present 2.5-11 micron spectrophotometric & imaging ISO observations of 28
Sf1, 29 Sf2 & 1 normal galaxy. The Sf1 & Sf2 MIR spectra are statistically
different: Sf1 have a strong power-law continuum of index -0.84+/-0.24 & weak
PAH emission bands. Sf2s have a weak continuum & very strong PAH emission
features with EW (equivalent widths) up to 7.2 micron. On the other hand, the
Sf1 and Sf2 PAH luminosities do not differ statistically and the 7 micron
continuum is ~8 times less luminous in Sf2s than in Sf1s. The PAH emission is
unrelated to the nuclear activity & arises in the bulge ISM. PAH EW are thus a
sensitive nuclear redenning indicator. These results are consistent with
unified schemes & imply that the Sf2 MIR nuclear continuum is, on the average,
extinguished by 92+/-37 visual magnitudes whereas it is directly visible in
Sf1s. The dispersion in Sf2's PAH EW is consistent with the expected spread in
viewing angles. Those Sf2s with PAH EW > 5 micron suffer from > 125 magnitudes
of extinction and are invariably weak X-ray sources. Such Sf2s represent the
highly inclined objects where our line of sight intercepts the full extent of
the torus. About 1/3rd of the Sf2s have PAH EW <= 2 micron, in the range of
Sf1s. Among them, those which have been observed in spectropolarimetry or IR
spectroscopy invariably display "hidden" broad lines. As proposed by Heisler et
al (1997), such Sf2s are most likely seen at grazing incidence such that one
has a direct view of both the "reflecting screen" and the torus inner wall
emitting the MIR continuum. Our observations thus constrain the screen & the
torus inner wall to be spatially co-located. Finally, the 9.7 micron Silicate
feature appears weakly in emission in Sf1s, implying that the torus vertical
thickness cannot significantly exceed E+24 cm-2

</DOC>
<DOC>
<DOCNO> 121380 </DOCNO>
Gravitational waves, baryogenesis, and dark matter from primordial black


  We discuss the hypothesis that the cosmological baryon asymmetry and entropy
were produced in the early Universe by the primordial black hole (PBHs)
evaporation.

</DOC>
<DOC>
<DOCNO> 12351 </DOCNO>
Paradoxical Magnetic Cooling in a Structural Transition Model


  In contrast to the experimentally widely used isentropic demagnetization
process for cooling to ultra-low temperatures we examine a particular classical
model system that does not cool, but rather heats up with isentropic
demagnetization. This system consists of several magnetite particles in a
colloidal suspension, and shows the uncommon behavior of disordering
structurally while ordering magnetically in an increasing magnetic field. For a
six-particle system, we report an uncommon structural transition from a ring to
a chain as a function of magnetic field and temperature.

</DOC>
<DOC>
<DOCNO> 68914 </DOCNO>
Electroweak Bloch-Nordsieck violation at the TeV scale: "strong" weak


  Hard processes at the TeV scale exhibit enhanced (double log) EW corrections
even for inclusive observables, leading to violation of the Bloch-Nordsieck
theorem. This effect, previously related to the non abelian nature of free EW
charges in the initial state (e- e+, e- p, p p ...), is here investigated for
fermion initiated hard processes and to all orders in EW couplings. We find
that the effect is important, especially for lepton initiated processes,
producing weak effects that in some cases compete in magnitude with the strong
ones. We show that this (double log) BN violating effect has a universal energy
dependence, related to the Sudakov form factor in the adjoint representation.
The role of this form factor is to suppress cross section differences within a
weak isospin doublet, so that at very large energy the cross sections for
left-handed electron-positron and neutrino-positron scattering become equal.
Finally, we briefly discuss the phenomenological relevance of our results for
future colliders.

</DOC>
<DOC>
<DOCNO> 120373 </DOCNO>
Launching of jets and the vertical structure of accretion disks


  The launching of magnetohydrodynamic outflows from accretion disks is
considered. We formulate a model for the local vertical structure of a thin
disk threaded by a poloidal magnetic field of dipolar symmetry. The model
consists of an optically thick disk matched to an isothermal atmosphere. The
disk is supposed to be turbulent and possesses an effective viscosity and an
effective magnetic diffusivity. In the atmosphere, if the magnetic field lines
are inclined sufficiently to the vertical, a magnetocentrifugal outflow is
driven and passes through a slow magnetosonic point close to the surface. We
determine how the rate of mass loss varies with the strength and inclination of
the magnetic field. In particular, we find that for disks in which the mean
poloidal field is sufficiently strong to stabilize the disk against the
magnetorotational instability, the mass loss rate decreases extremely rapidly
with increasing field strength, and is maximal at an inclination angle of 40-50
degrees. For turbulent disks with weaker mean fields, the mass loss rate
increases monotonically with increasing strength and inclination of the field,
but the solution branch terminates before achieving excessive mass loss rates.
Our results suggest that efficient jet launching occurs for a limited range of
field strengths, and a limited range of inclination angles in excess of 30
degrees. In addition, we determine the direction and rate of radial migration
of the poloidal magnetic flux, and discuss whether configurations suitable for
jet launching can be maintained against dissipation.

</DOC>
<DOC>
<DOCNO> 116727 </DOCNO>
General relativitistic theory of quasars. I


  In the paper physics/0007003 it was shown that after a correct definition of
the relations between observables in general relativity a horizon and a
singularity disappear. The general relativity in physical variables really
predicts an existence of supercompact relativistic stars and relativistic
galactic nuclei with (light and heavy) barionic and quark contents instead of
unphysical black holes. They have the radii near the gravitational radii and
emit the spectral lines with high redshifts and the energetic (X- and gamma)
photons. The quasars can be naturally interpreted as such relativistic
supercompact objects and their high redshifts explained mainly as a
gravitational redshift. The existing of the second mechanism of redshift in
addition to the Doppler shift leads to a normalization of all parameters of
quasars as the compact galactic nuclei. In principle new consequence of general
relativity is a prediction that some of quasars may be the relativistic stars
in the Galaxy. A short time variability of such quasars then can be naturally
explained.

</DOC>
<DOC>
<DOCNO> 150782 </DOCNO>
Spin and abelian electromagnetic duality on four-manifolds


  We investigate the electromagnetic duality properties of an abelian gauge
theory on a compact oriented four-manifold by analysing the behaviour of a
generalised partition function under modular transformations of the
dimensionless coupling constants. The true partition function is invariant
under the full modular group but the generalised partition function exhibits
more complicated behaviour depending on topological properties of the
four-manifold concerned. It is already known that there may be "modular
weights" which are linear combinations of the Euler number and Hirzebruch
signature of the four-manifold. But sometimes the partition function transforms
only under a subgroup of the modular group (the Hecke subgroup). In this case
it is impossible to define real spinor wave functions on the four-manifold. But
complex spinors are possible provided the background magnetic fluxes are
appropriately fractional rather that integral. This gives rise to a second
partition function which enables the full modular group to be realised by
permuting the two partition functions, together with a third. Thus the full
modular group is realised in all cases. The demonstration makes use of various
constructions concerning integral lattices and theta functions that seem to be
of intrinsic interest.

</DOC>
<DOC>
<DOCNO> 100873 </DOCNO>
Favourite sites of simple random walk


  We survey the current status of the list of questions related to the
favourite (or: most visited) sites of simple random walk on Z, raised by Pal
Erdos and Pal Revesz in the early eighties.

</DOC>
<DOC>
<DOCNO> 169953 </DOCNO>
A Critique on `Quantum No-Deleting Principle'


  The argument used, in a recent letter to Nature (Nature 130 vol 404, 2000) to
arrive at the `quantum-no-deleting principle' is erroneous. It is pointed out
here that there may not be anything like such a principle. In any case, the
claims made in the letter are beyond its working premise.

</DOC>
<DOC>
<DOCNO> 120464 </DOCNO>
New results from the HRX BL Lac sample


  We present results for the Hamburg BL Lac sample, based on data provided by
the RASS-BSC. By fitting a single power law to the X-ray data we find, in a
number of objects, an additional absorbing component to the galactic value of
NH, which might be attributed to intrinsic absorption. A more probable cause
seems however to be a curvature in the X-ray spectra in the sense that they are
more curved for steeper slopes. The known relation between the X-ray spectral
slope and the ratio between optical and X-ray flux alpha_ox also applies to
this BL Lac sample, even though less significant than in previous works. We
also find a dependence of X-ray luminosity on alpha_ox.

</DOC>
<DOC>
<DOCNO> 10197 </DOCNO>
Path Dependent Option Pricing: the path integral partial averaging


  In this paper I develop a new computational method for pricing path dependent
options. Using the path integral representation of the option price, I show
that in general it is possible to perform analytically a partial averaging over
the underlying risk-neutral diffusion process. This result greatly eases the
computational burden placed on the subsequent numerical evaluation. For
short-medium term options it leads to a general approximation formula that only
requires the evaluation of a one dimensional integral. I illustrate the
application of the method to Asian options and occupation time derivatives.

</DOC>
<DOC>
<DOCNO> 71285 </DOCNO>
Searching for Supersymmetric Dark Matter- The Directional Rate for


  The detection of the theoretically expected dark matter is central to
particle physics and cosmology. Current fashionable supersymmetric models
provide a natural dark matter candidate which is the lightest supersymmetric
particle (LSP). The theoretically obtained event rates are usually very low or
even undetectable. So the experimentalists would like to exploit special
signatures like the directional rates and the modulation effect. We study these
signatures in the present paper focusing on a specific class of non-isothermal
models involving flows of caustic rings.

</DOC>
<DOC>
<DOCNO> 84934 </DOCNO>
"Particle-like" singular solutions in Einstein-Maxwell theory and in


  Foundations of algebrodynamics based on earlier proposed equations of
biquaternionic holomorphy are briefly expounded. Free Maxwell and Yang-Mills
Eqs. are satisfied identically on the solutions of primary system which is also
related to the Eqs. of shear-free null congruences (SFC), and through them - to
the Einstein-Maxwell electrovacuum system. Kerr theorem for SFC reduces the
basic system to one algebraic equation, so that with each solution of the
latter some (singular) solution of vacuum Eqs. may be associated. We present
some exact solutions of basic algebraic and of related field Eqs. with compact
structure of singularities of electromagnetic field, in particular having the
form of figure "8" curve. Fundamental solution to primary system is analogous
to the metric and fields of the Kerr-Newman solution. In addition, in the
framework of algebraic dynamics the value of electric charge for this solution
is strictly fixed in magnitude and may be set equal to the elementary charge.

</DOC>
<DOC>
<DOCNO> 39742 </DOCNO>
Measurements of R_b, A_FB^b and A_FB^c in e+e- Collisions at 130-189 GeV


  The cross-section ratio Rb=sigma(e+e- to b-antib)/sigma(e+e- to q-antiq) and
the bottom and charm forward-backward asymmetries AFB^b and AFB^c are measured
using event samples collected by the OPAL detector at centre-of-mass energies
between 130 and 189 GeV. Events with bottom quark production are selected with
a secondary vertex tag, and a hemisphere charge algorithm is used to extract
AFB^b. In addition, the bottom and charm asymmetries are measured using leptons
from semileptonic decays of heavy hadrons and pions from D*+ to D0pi+ decays.
The results are in agreement with the Standard Model predictions.

</DOC>
<DOC>
<DOCNO> 101007 </DOCNO>
No bound for the first fixed point


  Our aim is to show that it is impossible to find a bound for the power of the
first fixed point of the aleph function.

</DOC>
<DOC>
<DOCNO> 68206 </DOCNO>
Search for TeV Strings and New Phenomena in Bhabha Scattering at LEP2


  A combined analysis of the data on Bhabha scattering at centre-of-mass
energies 183 and 189 GeV from the LEP experiments ALEPH, L3 and OPAL is
performed to search for effects of TeV strings in quantum gravity models with
large extra dimensions. No statistically significant deviations from the
Standard Model expectations are observed and lower limit on the string scale
M_S = 0.631 TeV at 95 % confidence level is derived. The data are used to set
lower limits on the scale of contact interactions ranging from 4.2 to 16.2 TeV
depending on the model. In a complementary analysis we derive an upper limit on
the electron size of 2.8 x 10^{-19} m at 95 % confidence level.

</DOC>
<DOC>
<DOCNO> 11324 </DOCNO>
Strong-Coupling Expansions for Multiparticle Excitations: Continuum and


  We present a new linked cluster expansion for calculating properties of
multiparticle excitation spectra to high orders. We use it to obtain the
two-particle spectra for systems of coupled spin-half dimers. We find that even
for weakly coupled dimers the spectrum is very rich, consisting of many bound
states. The number of bound states depends on both geometry of coupling and
frustration. Many of the bound states can only be seen by going to sufficiently
high orders in the perturbation theory, showing the extended character of the
pair-attraction.

</DOC>
<DOC>
<DOCNO> 67651 </DOCNO>
Subtraction method for NLO corrections in Monte-Carlo event generators


  In the case of the gluon-fusion process in deep-inelastic leptoproduction, I
explicitly show how to incorporate NLO corrections in a Monte-Carlo event
generator by a subtraction method. I calculate the parton densities to be used
by the event generator in terms of MSbar densities. The method is
generalizable. A particular motivation for treating the gluon-fusion process is
to treat diffractive deep-inelastic scattering properly, since in diffractive
scattering the gluon density dominates the quark densities. I also propose a
modified algorithm for treating parton kinematics in event generators; the new
algorithm results in much simpler formulae for the NLO corrections. A
disadvantage of the new method is that some of the generated events may have
negative weights. However, an adjustable cut-off function is present in the
formalism, and this permits a renormalization-group-like transformation that
can be used to at least reduce the proportion of events with negative weights.

</DOC>
<DOC>
<DOCNO> 169614 </DOCNO>
Distillation of GHZ states by selective information manipulation


  Methods for distilling maximally entangled tripartite (GHZ) states from
arbitrary entangled tripartite pure states are described. These techniques work
for virtually any input state. Each technique has two stages which we call
primary and secondary distillation. Primary distillation produces a GHZ state
with some probability, so that when applied to an ensemble of systems, a
certain percentage is discarded. Secondary distillation produces further GHZs
from the discarded systems. These protocols are developed with the help of an
approach to quantum information theory based on absolutely selective
information, which has other potential applications.

</DOC>
<DOC>
<DOCNO> 174458 </DOCNO>
Background Studies for the Neutral Current Detector Array in the Sudbury


  An array of 3He-filled proportional counters will be used in the Sudbury
Neutrino Observatory to measure the neutral-current interaction of neutrinos
and deuterium. We describe the backgrounds to this detection method.

</DOC>
<DOC>
<DOCNO> 170732 </DOCNO>
Entanglement Manipulation and Concentration


  We introduce a simple, experimentally realisable, entanglement manipulation
protocol for exploring mixed state entanglement. We show that for both
non-maximally entangled pure, and mixed polarisation-entangled two qubit
states, an increase in the degree of entanglement and purity, which we define
as concentration, is achievable.

</DOC>
<DOC>
<DOCNO> 13032 </DOCNO>
Techniques of replica symmetry breaking and the storage problem of the


  In this article the framework for Parisi's spontaneous replica symmetry
breaking is reviewed, and subsequently applied to the example of the
statistical mechanical description of the storage properties of a
McCulloch-Pitts neuron. The technical details are reviewed extensively, with
regard to the wide range of systems where the method may be applied. Parisi's
partial differential equation and related differential equations are discussed,
and a Green function technique introduced for the calculation of replica
averages, the key to determining the averages of physical quantities. The
ensuing graph rules involve only tree graphs, as appropriate for a
mean-field-like model. The lowest order Ward-Takahashi identity is recovered
analytically and is shown to lead to the Goldstone modes in continuous replica
symmetry breaking phases. The need for a replica symmetry breaking theory in
the storage problem of the neuron has arisen due to the thermodynamical
instability of formerly given solutions. Variational forms for the neuron's
free energy are derived in terms of the order parameter function x(q), for
different prior distribution of synapses. Analytically in the high temperature
limit and numerically in generic cases various phases are identified, among
them one similar to the Parisi phase in the Sherrington-Kirkpatrick model.
Extensive quantities like the error per pattern change slightly with respect to
the known unstable solutions, but there is a significant difference in the
distribution of non-extensive quantities like the synaptic overlaps and the
pattern storage stability parameter. A simulation result is also reviewed and
compared to the prediction of the theory.

</DOC>
<DOC>
<DOCNO> 150772 </DOCNO>
Vacuum energy in the presence of a magnetic string with delta function


  We present a calculation of the ground state energy of massive spinor fields
and massive scalar fields in the background of an inhomogeneous magnetic string
with potential given by a delta function. The zeta functional regularization is
used and the lowest heat kernel coefficients are calculated. The rest of the
analytical calculation adopts the Jost function formalism. In the numerical
part of the work the renormalized vacuum energy as a function of the radius $R$
of the string is calculated and plotted for various values of the strength of
the potential. The sign of the energy is found to change with the radius. For
both scalar and spinor fields the renormalized energy shows no logarithmic
behaviour in the limit $R\to 0$, as was expected from the vanishing of the heat
kernel coefficient $A_2$, which is not zero for other types of profiles.

</DOC>
<DOC>
<DOCNO> 39944 </DOCNO>
Cornering Higgs Bosons at LEP


  The most recent results of the searches for Higgs bosons in the data taken at
LEP in 1999 and their interpretation in a variety of theoretical framework are
reviewed.

</DOC>
<DOC>
<DOCNO> 71136 </DOCNO>
Magnetic catalysis in a P-even, chiral-invariant three-dimensional model


  The influence of an external constant and homogeneous magnetic field H on the
phase structure of the P-symmetric, chiral invariant 3-dimensional field theory
model with two four-fermion interaction structures is considered. An arbitrary
small (nonzero) magnetic field is shown to induce spontaneous violation of the
initial symmetry (magnetic catalysis). Moreover, vacuum of the model at H>0 can
be either P-symmetric or chiral invariant, depending on the values of the
coupling constants.

</DOC>
<DOC>
<DOCNO> 121764 </DOCNO>
Shear-Flow Driven Current Filamentation: Two-Dimensional


  The process of current filamentation in permanently externally driven,
initially globally ideal plasmas is investigated by means of two-dimensional
Magnetohydrodynamic (MHD)-simulations. This situation is typical for
astrophysical systems like jets, the interstellar and intergalactic medium
where the dynamics is dominated by external forces. Two different cases are
studied. In one case, the system is ideal permanently and dissipative processes
are excluded. In the second case, a system with a current density dependent
resistivity is considered. This resistivity is switched on self-consistently in
current filaments and allows for local dissipation due to magnetic
reconnection. Thus one finds tearing of current filaments and, besides, merging
of filaments due to coalescence instabilities. Energy input and dissipation
finally balance each other and the system reaches a state of constant magnetic
energy in time.

</DOC>
<DOC>
<DOCNO> 169727 </DOCNO>
A Tentative Expression of the Karolyhazy Uncertainty of the Space-Time


  In the existing expositions of the Karolyhazy model, quantum mechanical
uncertainties are mimicked by classical spreads. It is shown how to express
those uncertainties through entities of the future unified theory of general
relativity and quantum theory.

</DOC>
<DOC>
<DOCNO> 71017 </DOCNO>
Width difference in the D0-anti-D0 system


  The motivation most often cited in searches for D0-anti-D0 mixing lies with
the possibility of observing a signal from new physics which dominates that
from the Standard Model. We discuss recent theoretical and experimental results
in D0-anti-D0 mixing, including new experimental measurements from CLEO and
FOCUS collaborations and their interpretations.

</DOC>
<DOC>
<DOCNO> 152136 </DOCNO>
Open Superstring Theory and Superalgebra of the Brane Antibrane System


  Open superstring theory is formulated in terms of a nondegenerate
supertranslation algebra. A supercharge for a tachyonic superstring can be also
defined classically by taking into account the leakage of the supercurrent
which is compensated by fermionic and bosonic auxiliary fields. The
anticommutator of two supercharges of the tachyonic superstring does not
contain the zero eigenvalue and so this string is not a BPS state.
Brane-antibrane annihilation scenarios are described by these superalgebras
defined on the sum of world-volumes of a D-brane, an anti-D-brane and a
tachyonic superstring.

</DOC>
<DOC>
<DOCNO> 119723 </DOCNO>
The 2dF QSO Redshift Survey - I. The Optical QSO Luminosity Function


  We present a determination of the optical QSO luminosity function and its
cosmological evolution with redshift for a sample of over 6000 QSOs identified
primarily from the first observations of the 2dF QSO Redshift Survey (2QZ). For
QSOs with -26 < M_B < -23 and 0.35 < z < 2.3, we find that pure luminosity
evolution (PLE) models provide an acceptable fit to the observed redshift
dependence of the luminosity function. The luminosity function is best fit by a
two-power-law function of the form. Exponential luminosity evolution models,
both as a function of look-back time, and as a general second-order polynomial
with redshift, were found to provide acceptable fits to the dataset comprising
the 2QZ and the Large Bright Quasar Survey. Exponential evolution with
look-back time is prefered for q_0=0.05, while the polynomial evolution model
is prefered for q_0=0.5. The shape and evolution of the LF at low redshifts
(z<0.5) and/or high luminosities, not currently well sampled by the 2dF QSO
survey, may show departures from pure luminosity evolution, but the results
presented here show that over a significant range of redshift, PLE is a good
description of QSO evolution.

</DOC>
<DOC>
<DOCNO> 83192 </DOCNO>
Assisted Video Sequences Indexing : Motion Analysis Based on Interest


  This work deals with content-based video indexing. Our viewpoint is
semi-automatic analysis of compressed video. We consider the possible
applications of motion analysis and moving object detection : assisting moving
object indexing, summarising videos, and allowing image and motion queries. We
propose an approach based on interest points. As first results, we test and
compare the stability of different types of interest point detectors in
compressed sequences.

</DOC>
<DOC>
<DOCNO> 170142 </DOCNO>
Barnett-Pegg formalism of angle operators, revivals, and flux lines


  We use the Barnett-Pegg formalism of angle operators to study a rotating
particle with and without a flux line. Requiring a finite dimensional version
of the Wigner function to be well defined we find a natural time quantization
that leads to classical maps from which the arithmetical basis of quantum
revivals is seen. The flux line, that fundamentally alters the quantum
statistics, forces this time quantum to be increased by a factor of a winding
number and determines the homotopy class of the path. The value of the flux is
restricted to the rational numbers, a feature that persists in the infinite
dimensional limit.

</DOC>
<DOC>
<DOCNO> 12009 </DOCNO>
Field-induced 3- and 2-dimensional freezing in a quantum spin liquid


  Field-induced commensurate transverse magnetic ordering is observed in the
Haldane-gap compound \nd by means of neutron diffraction. Depending on the
direction of applied field, the high-field phase is shown to be either a
3-dimensional ordered N\'{e}el state or a short-range ordered state with
dominant 2-dimensional spin correlations. The structure of the high-field phase
is determined, and properties of the observed quantum phase transition are
discussed.

</DOC>
<DOC>
<DOCNO> 101966 </DOCNO>
Modular frames for Hilbert C*-modules and symmetric approximation of


  We give a comprehensive introduction to a general modular frame construction
in Hilbert C*-modules and to related modular operators on them. The Hilbert
space situation appears as a special case. The reported investigations rely on
the idea of geometric dilation to standard Hilbert C*-modulesover unital
C*-algebras that admit an orthonormal Riesz basis. Interrelations and
applications to classical linear frame theory are indicated. As an application
we describe the nature of families of operators {S_i} such that SUM_i
S*_iS_i=id_H, where H is a Hilbert space. Resorting to frames in Hilbert spaces
we discuss some measures for pairs of frames to be close to one another. Most
of the measures are expressed in terms of norm-distances of different kinds of
frame operators. In particular, the existence and uniqueness of the closest
(normalized) tight frame to a given frame is investigated. For Riesz bases with
certain restrictions the set of closetst tight frames often contains a multiple
of its symmetric orthogonalization (i.e. L\"owdin orthogonalization).

</DOC>
<DOC>
<DOCNO> 40361 </DOCNO>
Clopper-Pearson Bounds from HEP Data Cuts


  For the measurement of $N_s$ signals in $N$ events rigorous confidence bounds
on the true signal probability $p_{\rm exact}$ were established in a classical
paper by Clopper and Pearson [Biometrica 26, 404 (1934)]. Here, their bounds
are generalized to the HEP situation where cuts on the data tag signals with
probability $P_s$ and background data with likelihood $P_b<P_s$. The Fortran
program which, on input of $P_s$, $P_b$, the number of tagged data $N^Y$ and
the total number of data $N$, returns the requested confidence bounds as well
as bounds on the entire cumulative signal distribution function, is available
on the web. In particular, the method is of interest in connection with the
statistical analysis part of the ongoing Higgs search at the LEP experiments.

</DOC>
<DOC>
<DOCNO> 9247 </DOCNO>
Weak anisotropy and disorder dependence of the in-plane


  We report studies of the magnetoresistance (MR) in a two-dimensional electron
system in (100) Si-inversion layers, for perpendicular and parallel
orientations of the current with respect to the magnetic field in the 2D-plane.
The magnetoresistance is almost isotropic; this result does not support the
suggestion of the orbital origin of the MR in Si-inversion layer. In the
hopping regime, however, the MR contains a weak anisotropic component that is
non-monotonic in magnetic field. We found that the field, at which the MR
saturates, for different samples varies by a factor of two, being lower or
higher than the field of complete spin polarization of free carriers.
Therefore, the saturation of the MR can not be identified with the spin
polarization of free carriers.

</DOC>
<DOC>
<DOCNO> 40228 </DOCNO>
Using kaon regeneration to probe the quark mixing parameter cos(2 beta)


  We suggest a novel method to determine the sign of cos(2 beta) in the decays
B --> psi K, by creating interference between KL and KS final states via
``regeneration,'' that is propagation through a matter target region to convert
some KL to KS. The determination of this quantity resolves an ambiguity between
beta and (90o - beta) that remains after the standard measurements of sin(2
beta) and may turn out to be important in resolving whether the result is in
agreement with Standard Model predictions or indicates the presence of new
physics. We find the measurement is feasible at a B-factory, but requires
several years of high-luminosity running with a regeneration target affecting a
significant fraction of the detector.

</DOC>
<DOC>
<DOCNO> 11863 </DOCNO>
Adsorbate aggregation and relaxation of low-frequency vibrations


  We present a study of resonant vibrational coupling between adsorbates and an
elastic substrate at low macroscopic coverages. In the first part of the paper
we consider the situation when adsorbates form aggregates with high local
coverage. Based upon our previously published theory, we derive formulas
describing the damping rate of adsorbate vibrations for two cases of such
aggregation: (i) adsorbates attached to step edges and (ii) adsorbates forming
two-dimensional islands. We have shown that damping is governed by local
coverage. Particularly, for a wide range of resonant frequencies, the damping
rate of adsorbates forming well separated islands is described by the damping
rate formula for a periodic overlayer with the coverage equal to the local
coverage in the island. The second part of the paper is devoted to facilitating
the evaluation of damping rates for a disordered overlayer. The formula
describing the damping rate involves the parameter $\beta$ which is related to
the local density of phonon states at the substrate surface and does not allow
a closed-form representation. For substrates of isotropic and cubic symmetries,
we have developed a good analytical approximation to this parameter. For a vast
majority of cubic substrates the difference between the analytical
approximation and numerical calculation does not exceed 4%.

</DOC>
<DOC>
<DOCNO> 68561 </DOCNO>
On the gauge invariance of the DVCS amplitude


  We analyze in detail the problem of gauge invariance of the deeply vitual
Compton scattering (DVCS) amplitude. Using twist 3 one-gluon exchange diagram
contributions and the QCD equations of motion, we derive the general gauge
invariant expression of the DVCS amplitude on a (pseudo)scalar particle (pion,
$He^4$). Similarly to the case of deep inelastic scattering, the amplitude does
not depend on the twist-3 quark-gluon correlations at the Born level. The
contribution of the derived amplitude to the single-spin asymmetry with
longitudinally polarized lepton is calculated.

</DOC>
<DOC>
<DOCNO> 12640 </DOCNO>
Emergence of a dominant unit in a network of chaotic units with delayed


  We study here a model of globally coupled units with adaptive interaction
weights which has a delay in the updating rule. Simulations show that the model
with such delayed synaptic change exhibits dynamical self-organization of
network structure. With suitably chosen parameters, "dominant" unit emerges
spontaneously, in the sense that the connection from such unit to almost all of
the other units are especially strengthened. Such weight structure facilitates
the coherent activity among units.

</DOC>
<DOC>
<DOCNO> 12377 </DOCNO>
Thermodynamics of explosions


  We present our first attempts to formulate a thermodynamics-like description
of explosions. The motivation is partly a fundamental interest in
non-equilibrium statistical physics, partly the resemblance of an explosion to
the late stages of a heavy-ion collision. We perform numerical simulations on a
microscopic model of interacting billiard-ball like particles, and we analyse
the results of such simulations trying to identify collective variables
describing the degree of equilibrium during the explosion.

</DOC>
<DOC>
<DOCNO> 8679 </DOCNO>
Metal-insulator transition in 2D: resistance in the critical region


  The goal of this paper is to highlight several issues which are most crucial
for the understanding of the ``metal-insulator transition'' in two dimensions.
We discuss some common problems in interpreting experimental results on high
mobility Si MOSFETs. We analyze concepts and methods used to determine the
critical density of electrons at the metal-insulator transition. In particular,
we discuss the origin of the temperature dependence of the resistivity and
reasons for this dependence to flatten out at some electron density in the
vicinity of the metal-insulator transition. This flattening has recently been
proposed to indicate a true quantum phase transition. We suggest an alternative
interpretation of this result and demonstrate the consistency of our
proposition with the experimental data. One of the main questions, which arise
in connection with the transition, is whether or not the metallic state is
qualitatively distinct from a conventional disordered Fermi liquid. We analyze
the arguments in favor of both affirmative and negative answers to this
question and conclude that the experimental results accumulated up-to-date do
not provide convincing evidence for the new state of matter characterized by a
metallic-like residual conductivity. We also discuss in details the measurement
and control of the electron temperature; these issues are crucial for
interpreting the low-temperature experimental data.

</DOC>
<DOC>
<DOCNO> 152029 </DOCNO>
Current correlators in the Coulomb branch of N=4 SYM


  We study correlators of R-symmetry currents in the Coulomb branch of N = 4
supersymmetric gauge theory in the large-N limit, using the AdS/CFT
correspondence. In particular, we consider gauge fields in the presence of
gravity and scalar fields parameterizing the coset SL(6,R)/SO(6) in the context
of five-dimensional gauged supergravity. From a ten-dimensional point of view
these backgrounds correspond to continuous D3-brane distributions. We find the
surprising result that all 2-point functions of gauge currents fall into the
same universality class, irrespectively of whether they correspond to broken or
unbroken symmetries. We show that the problem of finding the spectrum can be
mapped into an equivalent Schroedinger problem for supersymmetric quantum
mechanics. The corresponding potential is the supersymmetric partner of the
potential arising in studies of the spectrum for massless scalars and
transverse graviton fluctuations in these backgrounds and the associated
spectra are also identical. We discuss in detail two examples where these
computations can be done explicitly as in the conformal case.

</DOC>
<DOC>
<DOCNO> 120158 </DOCNO>
Reflections on Gravity


  A pedagogical description of a simple ungeometrical approach to General
Relativity is given, which follows the pattern of well understood field
theories, such as electrodynamics. This leads quickly to most of the important
weak field predictions, as well as to the radiation damping of binary pulsars.
Moreover, certain consistency arguments imply that the theory has to be
generally invariant, and therefore one is bound to end up with Einstein's field
equations. Although this field theoretic approach, which has been advocated
repeatedly by a number of authors, starts with a spin-2 theory on Minkowski
spacetime, it turns out in the end that the flat metric is actually
unobservable, and that the physical metric is curved and dynamical.
  Short sections are devoted to tensor-scalar generalizations, the mystery of
the vacuum energy density, and quintessence.

</DOC>
<DOC>
<DOCNO> 151170 </DOCNO>
Equivalence Theorem for Lagrangians in Different Dimensions


  A proof is given for the observation that the equations of motion for the
companion Lagrangian without a square root, subject to some constraints, just
reduce to the equations of motion for the companion Lagrangian with a square
root in one less dimension. The companion Lagrangian is just an extension of
the Klein-Gordon Lagrangian to more fields in order to provide a field
description for strings and branes.

</DOC>
<DOC>
<DOCNO> 10768 </DOCNO>
Parametric Simultons in Nonlinear Lattices


  Parametric simultaneous solitary wave (simulton) excitations are shown
possible in nonlinear lattices. Taking a one-dimensional diatomic lattice with
a cubic potential as an example we consider the nonlinear coupling between the
upper cutoff mode of acoustic branch (as a fundamental wave) and the upper
cutoff mode of optical branch (as a second harmonic wave). Based on a
quasi-discreteness approach the Karamzin-Sukhorukov equations for two slowly
varying amplitudes of the fundamental and the second harmonic waves in the
lattice are derived when the condition of second harmonic generation is
satisfied. The lattice simulton solutions are explicitly given and the results
show that these lattice simultons can be nonpropagating when the wave vectors
of the fundamental wave and the second harmonic waves are exactly at $\pi/a$
(where $a$ is the lattice constant) and zero, respectively.

</DOC>
<DOC>
<DOCNO> 84474 </DOCNO>
Eleven dimensional supergravity as a constrained topological field


  We describe a new first-order formulation of D=11 supergravity which shows
that that theory can be understood to arise from a certain topological field
theory by the imposition of a set of local constraints on the fields, plus a
lagrange multiplier term. The topological field theory is of interest as the
algebra of its constraints realizes the D=11 supersymmetry algebra with central
charges.

</DOC>
<DOC>
<DOCNO> 150797 </DOCNO>
Fuzzy Gravitons From Uncertain Spacetime


  The recently proposed remarkable mechanism explaining ``stringy exclusion
principle" on an Anti de Sitter space is shown to be another beautiful
manifestation of spacetime uncertainty principle in string theory as well as in
M theory. Put in another way, once it is realized that the graviton of a given
angular momentum is represented by a spherical brane, we deduce the maximal
angular momentum directly from either the relation $\Delta t\Delta x^2>l_p^3$
in M theory or $\Delta t\Delta x>\ap$ in string theory. We also show that the
result of hep-th/0003075 is similar to results on D2-branes in SU(2) WZW model.
Using the dual D2-brane representation of a membrane, we obtain the
quantization condition for the size of the membrane.

</DOC>
<DOC>
<DOCNO> 40317 </DOCNO>
Search for direct production of a2(1320) and f2(1270) mesons in e+e-


  A search for direct production of C-even resonances a2(1320) and f2(1270) in
e+e- annihilation was performed with SND detector at VEPP-2M e+e- collider. The
upper limits of electronic widths of these mesons were obtained at 90%
confidence level:
        Gamma(a2(1320) \to e+e-) < 0.56 eV,
        Gamma(f2(1270) \to e+e-) < 0.11 eV.

</DOC>
<DOC>
<DOCNO> 83072 </DOCNO>
About the globular homology of higher dimensional automata


  We introduce a new simplicial nerve of higher dimensional automata whose
homology groups yield a new definition of the globular homology. With this new
definition, the drawbacks noticed with the construction of math.CT/9902151
disappear. Moreover the important morphisms which associate to every globe its
corresponding branching area and merging area of execution paths become
morphisms of simplicial sets.

</DOC>
<DOC>
<DOCNO> 11030 </DOCNO>
Microscopic theory for quantum mirages in quantum corrals


  Scanning tunneling microscopy permits to image the Kondo resonance of a
single magnetic atom adsorbed on a metallic surface. When the magnetic impurity
is placed at the focus of an elliptical quantum corral, a Kondo resonance has
been recently observed both on top of the impurity and on top of the focus
where no magnetic impurity is present. This projection of the Kondo resonance
to a remote point on the surface is referred to as quantum mirage. We present a
quantum mechanical theory for the quantum mirage inside an ideal quantum corral
and predict that the mirage will occur in corrals with shapes other than
elliptical.

</DOC>
<DOC>
<DOCNO> 170264 </DOCNO>
Quantum Computing Using Electrons Floating on Liquid Helium


  The system of electrons trapped in vacuum above the liquid helium surface
displays the highest mobilities known in condensed matter physics. We provide a
brief summary of the experimental and theoretical results obtained for this
system. We then show that a quasi-2D set of N > 10^8 electrons in vacuum
trapped in 1D hydrogenic levels above a micron-thick helium film can be used as
an easily manipulated strongly interacting set of quantum bits. Individual
electrons are laterally confined by micron sized metal pads below the helium.
Information is stored in the lowest hydrogenic levels. Using electric fields at
temperatures of 10 mK, changes in the wave function can be made in nanoseconds.
Wave function coherence times are .1 millisecond. The wave function is read out
using an inverted dc voltage which releases excited electrons from the surface,
or using SETs attached to the metal pads which control the electrons.

</DOC>
<DOC>
<DOCNO> 102466 </DOCNO>
n-dimensional links, their components, and their band-sums


  We prove the following results (1) (2) (3) on relations between $n$-links and
their components. (1) Let L=(L_1, L_2) be a (4k+1)-link (4k+1\geq 5). Then we
have Arf L=Arf L_1+Arf L_2. (2) Let L=(L_1, L_2) be a (4k+3)-link (4k+3\geq3).
Then we have \sigma L=\sigma L_1+\sigma L_2. (3) Let n\geq1. Then there is a
nonribbon n-link L=(L_1, L_2) such that L_i is a trivial knot.
  We prove the following results (4) (5) (6) (7) on band-sums of n-links. (4)
Let L=(L_1, L_2) be a (4k+1)-link (4k+1\geq 5). Let K be a band-sum of L. Then
we have Arf K=Arf L_1+Arf L_2. (5) Let L=(L_1, L_2) be a (4k+3)-link
(4k+3\geq3). Let K be a band-sum of L. Then we have \sigma K=\sigma L_1+ \sigma
L_2.
  The above (4)(5) imply the following (6). (6) Let 2m+1\geq3. There is a set
of three (2m+1)-knots K_0, K_1, K_2 with the following property: K_0 is not any
band-sum of any n-link L=(L_1, L_2) such that L_i is equivalent to K_i (i=1,2).
(7) Let n\geq1. Then there is an n-link L=(L_1, L_2) such that L_i is a trivial
knot (i=1,2) and that a band-sum of $L$ is a nonribbon knot.
  We prove a 1-dimensional version of (1). (8) Let L=(L_1, L_2) be a proper
1-link. Then Arf L =Arf L_1+ Arf L_2+{1/2}\{\beta^*(L)$+mod4 $\{{1/2}lk (L)\}\}
  =Arf L_1+Arf L_2+mod2 \{\lambda (L)\}, where \beta^*(L) is the
Saito-Sato-Levine invariant and \lambda(L) is the Kirk-Livingston invariant.

</DOC>
<DOC>
<DOCNO> 11229 </DOCNO>
Fermi and non-Fermi Liquid Behavior in Quantum Impurity Systems:


  We review a recently developed method, based on an exact auxiliary boson
representation, to describe both Fermi liquid and non-Fermi liquid behavior in
quantum impurity systems. Coherent spin and charge fluctuation processes are
taken into account in a self-consistent way and are shown to include {\it all}
leading and subleading infrared singularities at any given order of the
self-consistent loop expansion of the free energy. As a consequence, for the
SU(N)$\times$ SU(M) Anderson impurity models the correct temperature dependence
of the susceptibility is recovered over the entire temperature range, including
Fermi liquid or non-Fermi liquid behavior below the Kondo temperature $T_K$. As
a standard diagram technique the presented method has the potential to be
generalized to correlated electron systems on a lattice.

</DOC>
<DOC>
<DOCNO> 67643 </DOCNO>
Extra dimensions and Strong Neutrino-Nucleon interactions above


  Cosmic ray events above $10^{20}$ eV are on the verge of confronting
fundamental particle physics. The neutrino is the only candidate primary among
established particles capable of crossing 100 Mpc intergalactic distances
unimpeded. The magnitude of $\nu N$ cross sections indicated by events, plus
consistency with the Standard Model at low-energy, point to new physics of
massive spin-2 exchange. In models based on extra dimensions, we find that the
$\nu N$ cross section rises to typical hadronic values of between 1 and 100 mb
at energies above $10^{20}$ eV. Our calculations take into account constraints
of unitarity. We conclude that air-showers observed with energies above
$10^{19}$ eV are consistent with neutrino primaries and extra-dimension models.
An {\it upper bound} of 1-10 TeV on the mass scale at which graviton exchange
becomes strong in current Kaluza-Klein models follows.

</DOC>
<DOC>
<DOCNO> 69000 </DOCNO>
Recalculation of Proton Compton Scattering in Perturbative QCD


  At very high energy and wide angles, Compton scattering on the proton (gamma
p -> gamma p) is described by perturbative QCD. The perturbative QCD
calculation has been performed several times previously, at leading twist and
at leading order in alpha_s, with mutually inconsistent results, even when the
same light-cone distribution amplitudes have been employed. We have
recalculated the helicity amplitudes for this process, using contour
deformations to evaluate the singular integrals over the light-cone momentum
fractions. We do not obtain complete agreement with any previous result. Our
results are closest to those of the most recent previous computation, differing
significantly for just one of the three independent helicity amplitudes, and
only for backward scattering angles. We present results for the unpolarized
cross section, and for three different polarization asymmetries. We compare the
perturbative QCD predictions for these observables with those of the handbag
and diquark models. In order to reduce uncertainties associated with alpha_s
and the three-quark wave function normalization, we have normalized the Compton
cross section using the proton elastic form factor. The theoretical predictions
for this ratio are about an order of magnitude below existing experimental
data.

</DOC>
<DOC>
<DOCNO> 40244 </DOCNO>
Charged-Lepton-Flavour Violation in Kaon Decays in Supersymmetric


  We discuss rare kaon decays that violate charged-lepton flavour conservation
in supersymmetric theories with and without R parity, in view of possible
experiments using an intense proton source as envisaged for a neutrino factory.
In the Minimal Supersymmetric Standard Model, such decays are generated by box
diagrams involving charginos and neutralinos, but the limits from \mu -> e
\gamma, \mu-e conversion and \Delta m_K constrain the branching ratios to
challengingly small values. However, this is no longer the case in R-violating
theories, where such decays may occur at tree level at rates close to the
present experimental limits. Within this framework, we obtain bounds on
products of LL\bar{E} and LQ\bar{D} operators from the experimental upper
limits on K^0 -> \mu^\pm e^\mp and K^{\pm,0} -> \pi^{\pm,0} \mu^\pm e^\mp
decays. We also note the possibility of like-sign lepton decays K^\pm ->
\pi^\mp \ell^\pm \ell^\pm in the presence of non-zero \tilde{b}_L-\tilde{b}_R
mixing. We conclude that rare kaon decays violating charged-lepton flavour
conservation could be an interesting signature of R violation.

</DOC>
<DOC>
<DOCNO> 69181 </DOCNO>
Quantum Hadrodynamics: Evolution and Revolution


  The underlying philosophy and motivation for quantum hadrodynamics (QHD),
namely, relativistic field theories of nuclear phenomena featuring manifest
covariance, have evolved over the last quarter century in response to
successes, failures, and sharp criticisms. A recent revolution in QHD, based on
modern effective field theory and density functional theory perspectives,
explains the successes, provides antidotes to the failures, rebuts the
criticisms, and focuses the arguments in favor of a covariant representation.

</DOC>
<DOC>
<DOCNO> 178416 </DOCNO>
Deeply bound levels in kaonic atoms


  Using a microscopic antikaon-nucleus optical potential recently developed by
Ramos and Oset (nucl-th/9906016, in print in Nuclear Physics A) from a chiral
model, we calculate strong interaction shifts and widths for $K^-$ atoms. This
purely theoretical potential gives an acceptable description of the measured
data ($\chi^2/{\rm num.data}= 3.8$), though it turns out to be less attractive
than what can be inferred from the existing kaon atomic data. We also use a
modified potential, obtained by adding to the latter theoretical one a s-wave
term which is fitted to known experimental kaonic data ($\chi^2/{\rm
degree of freedom}= 1.6$), to predict deeply bound $K^-$ atomic levels, not
detected yet. This improved potential predicts, in general, states even
narrower than those recently reported by Friedman and Gal. (Phys.Let.B459,
1999, 43). This reinforces the idea that these deeply atomic states can be
detected and resolved by using suitable nuclear reactions. Besides, we also
study $K^-$ and $\bar K^0$ nuclear bound states and compute binding energies
and widths, for both species of antikaons, in $^{12}$C, $^{40}$Ca and
$^{208}$Pb. Despite of restricting our study only to potentials obtained from
best fits to the known kaonic atom data, the dynamics of these nuclear bound
states depend dramatically on the particular optical potential used.

</DOC>
<DOC>
<DOCNO> 151993 </DOCNO>
Strong Coupling Effects in non-commutative spaces from OM Theory and


  We show that a four-parameter class of 3+1 dimensional NCOS theories can be
obtained by dimensional reduction on a general 2-torus from OM theory.
Compactifying two spatial directions of NCOS theory on a 2-torus, we study the
transformation properties under the $SO(2,2;Z)$ T-duality group. We then
discuss non-perturbative configurations of non-commutative super Yang-Mills
theory. In particular, we calculate the tension for magnetic monopoles and
(p,q) dyons and exhibit their six-dimensional origin, and construct a
supergravity solution representing an instanton in the gauge theory. We also
compute the potential for a monopole-antimonopole in the supergravity
approximation.

</DOC>
<DOC>
<DOCNO> 12431 </DOCNO>
Fourth Order Diffusion Monte Carlo Algorithms for Solving Quantum


  By decomposing the important sampled imaginary time Schr\"odinger evolution
operator to fourth order with positive coefficients, we derived a number of
distinct fourth order Diffusion Monte Carlo algorithms. These sophisticated
algorithms require higher derivatives of the drift velocity and local energy
and are more complicated to program. However, they allowed very large time
steps to be used, converged faster with lesser correlations, and virtually
eliminated the step size error. We demonstrated the effectiveness of these
quartic algorithms by solving for the ground state properties of bulk liquid
helium.

</DOC>
<DOC>
<DOCNO> 101225 </DOCNO>
The uncountable spectra of countable theories


  Let T be a complete, first-order theory in a finite or countable language
having infinite models. Let I(T,kappa) be the number of isomorphism types of
models of T of cardinality \kappa. We denote by \mu (respectively \hat\mu) the
number of cardinals (respectively infinite cardinals) less than or equal to
\kappa. We prove that I(T,\kappa), as a function of \kappa > \aleph_0, is the
minimum of 2^{\kappa} and one of the following functions:
  1. 2^{\kappa};
  2. the constant function 1;
  3. |\hat\mu^n/{\sim_G}|-|(\hat\mu - 1)^n/{\sim_G}| if \hat\mu<\omega for
some 1<n<\omega and \hat\mu if \hat\mu >= \omega some group G <= Sym(n);
  4. the constant function \beth_2;
  5. \beth_{d+1}(\mu) for some infinite, countable ordinal d;
  6. \sum_{i=1}^d \Gamma(i) where d is an integer greater than 0 (the depth of
T) and \Gamma(i) is either \beth_{d-i-1}(\mu^{\hat\mu}) or
\beth_{d-i}(\mu^{\sigma(i)} + \alpha(i)), where \sigma(i) is either 1,
\aleph_0 or \beth_1, and \alpha(i) is 0 or \beth_2; the first possibility for
\Gamma(i) can occur only when d-i > 0.

</DOC>
<DOC>
<DOCNO> 85262 </DOCNO>
A generalized linear Hubble law for an inhomogeneous barotropic Universe


  In this work, I present a generalized linear Hubble law for a barotropic
spherically symmetric inhomogeneous spacetime, which is in principle compatible
with the acceleration of the cosmic expansion obtained as a result of high
redshift Supernovae data. The new Hubble function, defined by this law, has two
additional terms besides an expansion one, similar to the usual volume
expansion one of the FLRW models, but now due to an angular expansion. The
first additional term is dipolar and is a consequence of the existence of a
kinematic acceleration of the observer, generated by a negative gradient of
pressure or of mass-energy density. The second one is quadrupolar and due to
the shear. Both additional terms are anisotropic for off-centre observers,
because of to their dependence on a telescopic angle of observation. This
generalized linear Hubble law could explain, in a cosmological setting, the
observed large scale flow of matter, without to have recourse to peculiar
velocity-type newtonian models. It is pointed out also, that the matter dipole
direction should coincide with the CBR dipole one.

</DOC>
<DOC>
<DOCNO> 118623 </DOCNO>
GRB990510: on the possibility of a beamed X-ray afterglow


  We discuss the prompt emission of the gamma-ray burst (GRB) 990510 and its
subsequent X-ray afterglow from 8.0 to 44.3 hrs after the prompt emission,
using observations with the Gamma-ray Burst Monitor and Narrow Field
Instruments on BeppoSAX. In the 40-700 keV band, GRB990510 had a fluence of
\~1.9x10^{-5}erg cm^{-2}, whereas it reached a peak flux of ~2.4x10^{-6}erg
cm^{-2} s^{-1}. The X-ray afterglow decay light curve can be satisfactorily
described by a single power law with index of -1.42+/-0.07. Both the X-ray and
optical behaviour of the afterglow can be explained by gamma-ray burst debris
expanding as a jet; we find that the cooling frequency is (fixed) between the
optical and X-ray wavelength bands.

</DOC>
<DOC>
<DOCNO> 178873 </DOCNO>
Simulation of Nucleus-Nucleus Interactions in the Framework of the


  The intranuclear cascade model overestimates the multiplicity of produced
mesons in nucleus-nucleus interactions without taking into account meson and
baryon resonance production. Inclusion of the resonances leads to decreasing
multiplicity of mesons, neutrons and protons. In order to overcome the problem,
it is proposed to use the FRITIOF model adapted to low energies in a
combination with the reggeon theory inspired model of nuclear destruction. It
is shown that the combination allows one to reproduce satisfactory the meson
and baryon yields in the nucleus-nucleus collisions at the energy of 3.3
GeV/nucleon. The combined model works faster than typical quantum molecular
dynamic model, and allows one to estimate the data needed for creation of
electro-nuclear amplifier.

</DOC>
<DOC>
<DOCNO> 69443 </DOCNO>
Structure of the Yang-Mills vacuum in the zero modes enhancement quantum


  We have formulated new quantum model of the QCD vacuum using the effective
potential approach for composite operators. It is based on the existence and
importance of such kind of the nonperturbative, topologically nontrivial
excitations of gluon field configurations, which can be effectively correctly
described by the $q^{-4}$-type behavior of the full gluon propagator in the
deep infrared domain. The ultraviolet part of the full gluon propagator was
approximated by the asymptotic freedom to-leading order perturbative logarithm
term of the running coupling constant. Despite the vacuum energy density
remains badly divergent, we have formulated a method how to establish a finite
(in the ultraviolet limit) relation between the two scale parameters of our
model. We have expressed the asymptotic scale parameter as $pure number$ times
the nonperturbative scale, which is inevitably contained in any realistic
Ansatz for the full gluon propagator.

</DOC>
<DOC>
<DOCNO> 69051 </DOCNO>
B->rho pi and the unitary angle alpha


  The role of the decay mode B->rho pi for the determination of the unitarity
angle alpha is critically examined in view of the smaller than expected ratio
B(B->rho+/- pi-/+)/B(B->rho0 pi+/-) found by the CLEO collaboration.

</DOC>
<DOC>
<DOCNO> 11544 </DOCNO>
Small Numerators Canceling Small Denominators: Is Dyson's Hierarchical


  We present an analytical method to solve Dyson's hierarchical model,
involving the scaling variables near the high-temperature fixed point. The
procedure seems plagued by the presence of small denominators as in
perturbative expansions near integrable systems in Hamiltonian mechanics.
However, in all cases considered, a zero denominator always comes with a zero
numerator. We conjecture that these cancellations occur in general, suggesting
that the model has remarkable features reminiscent of the integrable systems.

</DOC>
<DOC>
<DOCNO> 121272 </DOCNO>
The supernova remnant RX J0852.0-4622: radio characteristics and


  We present new radio observations of the recently identified, young Galactic
supernova remnant (SNR) RX J0852.0-4622 (G266.2-01.2) made at 1.40 GHz with a
resolution of 14.9 arcmin. These results, along with other radio observations
from the literature, are used to derive the extent, morphology and radio
spectrum of the remnant. The possible age and distance to this remnant are
discussed, along with the consequences of its properties - especially its low
radio surface brightness - for statistical studies of Galactic SNRs. The
extended features identified by Combi et al. (1999) are considered, and we
conclude that these are probably unrelated to the new remnant. If RX
J0852.0-4622 is nearby, as is suggested by the available gamma-ray data, then
the range of intrinsic radio luminosities for SNRs of the same diameter may be
much larger than was previously thought.

</DOC>
<DOC>
<DOCNO> 68094 </DOCNO>
QCD sum rules for J/psi in the nuclear medium: calculation of the Wilson


  We calculate the Wilson coefficients of all dimension 6 gluon operators with
non zero spin in the correlation function between two heavy vector currents.
For the twist-4 part, we first identify the three independent gluon operators,
and then proceed with the calculation of the Wilson coefficients using the
fixed point gauge. Together with the previous calculation of the Wilson
coefficients for the dimension 6 scalar gluon operators by Nikolaev and
Radyushkin, our result completes the list of all the Wilson coefficients of
dimension 6 gluon operators in the correlation function between heavy vector
currents. We apply our results to investigate the mass of $J/\psi$ in nuclear
matter using QCD sum rules. Using an upper bound estimate on the matrix
elements of the dimension 6 gluon operators to linear order in density, we find
that the density dependent contribution from dimension 6 operators is less than
40% of the dimension 4 operators with opposite sign. The final result gives
about -4 MeV mass shift for the charmonium at rest in nuclear matter.

</DOC>
<DOC>
<DOCNO> 68992 </DOCNO>
Neutrino mass matrix suppression by Abelian charges with see-saw


  We have investigated a neutrino mass matrix model without supersymmetry
including three see-saw right-handed neutrinos around order $10^{12}$ GeV
masses, aiming at a picture with all small numbers explained as being due to
approximately conserved gauge charges. The prediction of the solar neutrino
mixing angle is given by $\sin^22\theta_{\odot}= 3 {+3\atop -2}\times10^{-2}$;
in fact, the solar mixing angle is, apart from detailed order unity
corrections, equal to the Cabibbo angle. Furthermore the ratio of the solar
neutrino mass square difference to that for the atmospheric neutrino
oscillation is predicted to $6 {+11\atop -4}\times10^{-4}$ and is given by the
same Cabibbo angle related parameter $\xi$ as $6 \xi^4$.

</DOC>
<DOC>
<DOCNO> 8281 </DOCNO>
Ferromagnetism in III-V and II-VI semiconductor structures


  The current status of research on the carrier-mediated ferromagnetism in
tetrahedrally coordinated semiconductors is briefly reviewed. The experimental
results for III-V semiconductors, where Mn atoms introduce both spins and
holes, are compared to the case of II-VI compounds, in which the ferromagnetism
has been observed for the modulation-doped p-type Cd1-xMnxTe/Cd1-y-zMgyZnzTe:N
heterostructures, and more recently, in Zn1-xMnxTe:N epilayers. On the
theoretical side, a model is presented, which takes into account: (i) strong
spin-orbit and kp couplings in the valence band; (ii) the effect of confinement
and strain upon the hole density-of-states and response function, and (iii) the
influence of disorder and carrier-carrier interactions, particularly near the
metal-to-insulator transition. A comparison between experimental and
theoretical results demonstrates that the model can describe the magnetic
circular dichroism, the values of TC observed in the studied systems as well as
explain the directions of the easy axis and the magnitudes of the corresponding
anisotropy fields as a function of confinement and biaxial strain. Various
suggestions concerning design of novel ferromagnetic semiconductor systems are
described.

</DOC>
<DOC>
<DOCNO> 13430 </DOCNO>
Griffiths phase of the Kondo insulator fixed point


  Heavy fermion compounds have long been identified as systems which are
extremely sensitive to the presence of impurities and other imperfections. In
recent years, both experimental and theoretical work has demonstrated that such
disorder can lead to unusual, non-Fermi liquid behavior for most physical
quantities. In this paper, we show that this anomalous sensitivity to disorder,
as well as the resulting Griffiths phase behavior, directly follow from the
proximity of metallic heavy fermion systems to the Kondo insulator fixed point.

</DOC>
<DOC>
<DOCNO> 8421 </DOCNO>
Intrinsic tunneling spectroscopy in small Bi2212 mesas


  We present intrinsic tunneling spectroscopy measurements on small
Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ mesas. The tunnel conductance curves show both
sharp peaks at the superconducting gap voltage and broad humps representing the
$c$-axis pseudo-gap. The superconducting gap vanishes at $T_c$, while the
pseudo-gap exists well above $T_c$. Our observation implies that the
superconducting and pseudo-gaps represent different coexisting phenomena.

</DOC>
<DOC>
<DOCNO> 169851 </DOCNO>
Fermionic quantum computation


  We define a model of quantum computation with local fermionic modes (LFMs)
--- sites which can be either empty or occupied by a fermion. With the standard
correspondence between the Foch space of $m$ LFMs and the Hilbert space of $m$
qubits, simulation of one fermionic gate takes $O(m)$ qubit gates and vice
versa. We show that using different encodings, the simulation cost can be
reduced to $O(\log m)$ and a constant, respectively. Nearest-neighbors
fermionic gates on a graph of bounded degree can be simulated at a constant
cost. A universal set of fermionic gates is found. We also study computation
with Majorana fermions which are basically halves of LFMs. Some connection to
qubit quantum codes is made.

</DOC>
<DOC>
<DOCNO> 83191 </DOCNO>
Task Frames


  Forty years ago Dijkstra introduced the current conventional execution of
routines. It places activation frames onto a stack. Each frame is the internal
state of an executing routine. The resulting application execution is not
easily helped by an external system. This presentation proposes an alternative
execution of routines. It places task frames onto the stack. A task frame is
the call of a routine to be executed. The feasibility of the alternative
execution is demonstrated by a crude implementation. As described elsewhere, an
application which executes in terms of tasks can be provided by an external
system with a transparent reliable, distributed, heterogeneous, adaptive,
dynamic, real-time, parallel, secure or other execution. By extending the crude
implementation, this presentation outlines a simple transparent parallel
execution.

</DOC>
<DOC>
<DOCNO> 71647 </DOCNO>
Local equilibrium in heavy-ion collisions: Microscopic analysis of a


  We study the local equilibrium in the central $V = 125$ fm$^3$ cell in
heavy-ion collisions at energies from 10.7 AGeV (AGS) to 160 AGeV (SPS)
calculated in the microscopic transport model. In the present paper the hadron
yields and energy spectra in the cell are compared with those of infinite
nuclear matter, as calculated within the same model. The agreement between the
spectra in the two systems is established for times $t \geq 10$ fm/$c$ in the
central cell. The cell results do not deviate noticeably from the infinite
matter calculations with rising incident energy, in contrast to the apparent
discrepancy with predictions of the statistical model (SM) of an ideal hadron
gas. The entropy of this state is found to be very close to the maximum
entropy, while hadron abundances and energy spectra differ significantly from
those of the SM.

</DOC>
<DOC>
<DOCNO> 118063 </DOCNO>
HST Photometry and Keck Spectroscopy of the Rich Cluster MS1054-03:


  We present a study of 81 I selected, spectroscopically-confirmed members of
the X-ray cluster MS1054-03 at z=0.83. Redshifts and spectral types were
determined from Keck spectroscopy. Morphologies and accurate colors were
determined from a large mosaic of HST WFPC2 images in F606W and F814W.
Early-type galaxies constitute only 44% of this galaxy population. Thirty-nine
percent are spiral galaxies, and 17% are mergers. The early-type galaxies
follow a tight and well-defined color-magnitude relation, with the exception of
a few outliers. The observed scatter is 0.029 +- 0.005 magnitudes in restframe
U-B. Most of the mergers lie close to the CM relation defined by the early-type
galaxies. They are bluer by only 0.07 +- 0.02 magnitudes, and the scatter in
their colors is 0.07 +- 0.04 magnitudes. Spiral galaxies in MS1054-03 exhibit a
large range in their colors. The bluest spiral galaxies are 0.7 magnitudes
bluer than the early-type galaxies, but the majority is within +- 0.2
magnitudes of the early-type galaxy sequence. The red colors of the mergers and
the majority of the spiral galaxies are reflected in the fairly low
Butcher-Oemler blue fraction of MS1054-03: f_B=0.22 +- 0.05. The slope and
scatter of the CM relation of early-type galaxies are roughly constant with
redshift, confirming previous studies that were based on ground-based color
measurements and very limited membership information. However, the scatter in
the combined sample of early-type galaxies and mergers is twice as high as the
scatter of the early-type galaxies alone. This is a direct demonstration of the
``progenitor bias'': high redshift early-type galaxies seem to form a
homogeneous, old population because the progenitors of the youngest present-day
early-type galaxies are not included in the sample.

</DOC>
<DOC>
<DOCNO> 174545 </DOCNO>
n-p Short-Range Correlations from (p,2p + n) Measurements


  Recently, a new technique for measuring short-range NN correlations in nuclei
(NN SRCs) was reported by the E850 collaboration, using data from the EVA
spectrometer at the AGS at Brookhaven Nat. Lab. In this talk, we will report on
a larger set of data from new measurement by the collaboration, utilizing the
same technique. This technique is based on a very simple kinematic approach.
For quasi-elastic knockout of protons from a nucleus ($^{12}$C(p,2p) was used
for the current work), we can reconstruct the momentum {\bf p$_f$} of the
struck proton in the nucleus before the reaction, from the three momenta of the
two detected protons, {\bf p$_1$} and {\bf p$_2$} and the three momentum of the
incident proton, {\bf p$_0$} : {\bf p$_f$} = {\bf p$_1$} + {\bf p$_2$} - {\bf
p$_0$} If there are significant n-p SRCs, then we would expect to find a
neutron with momentum -{\bf p$_f$} in coincidence with the two protons,
provided {\bf p$_f$} is larger than the Fermi momentum $k_F$ for the nucleus
(${\sim}$220 MeV/c for $^{12}$C). Our results reported here confirm the earlier
results from the E850 collaboration.

</DOC>
<DOC>
<DOCNO> 118671 </DOCNO>
Intrinsic Differences in the Inner Jets of High- and Low-Optically


  A significant fraction of compact radio-loud quasars display most of the
characteristics of relativistically beamed, high-optical polarization blazars,
yet are weakly polarized in the optical regime. We have used the VLBA at 22 and
43 GHz to look for differences in the parsec-scale magnetic field structures of
18 high- and low-optically polarized, compact radio-loud quasars (HPQs and
LPRQs, respectively). We find a strong correlation between the polarization
level of the unresolved parsec-scale radio core at 43 GHz and overall optical
polarization of the source, which suggests a common (possibly co-spatial)
origin for the emission at these two wavelengths. The magnetic fields of the
polarized 43 GHz radio cores are aligned roughly transverse to the jet axis.
Similar orientations are seen in the optical, suggesting that the polarized
flux at both wavelengths is due to one or more strong transverse shocks located
very close to the base of the jet. In LPRQs, these shocks appear to be weak
near the core, and gradually increase in strength down the jet. The LPRQs in
our sample tend to have less luminous radio cores than the HPQs, and jet
components with magnetic fields predominantly parallel to the flow. The
components in HPQ jets, on the other hand, tend to have transverse alignments.
These differences cannot be accounted for by a simple model in which HPQs and
LPRQs are the same type of object, seen at different angles to the line of
sight. A more likely scenario is that LPRQs represent a quiescent phase of
blazar activity, in which the inner jet flow does not undergo strong shocks.

</DOC>
<DOC>
<DOCNO> 169776 </DOCNO>
Indistinguishability and nonlocality in Einstein-Podolsky-Rosen


  Quasi-set theory allows us a non trivial relation between
indistinguishability and nonlocality into the context of Einstein-
Podolsky-Rosen experiment. Quasi-set theory is a set theory which provides a
manner for dealing with collections of indistinguishable but not identical
elementary particles.

</DOC>
<DOC>
<DOCNO> 13531 </DOCNO>
Legendre's Relation and the Quantum Equivalence osp(4|4)_(1) =


  Using explicit results for the four-point correlation functions of the
Wess-Zumino-Novikov-Witten (WZNW) model we discuss the conformal embedding
osp(4|4)_(1) = osp(2|2)_(-2) + su(2)_(0). This embedding has emerged in Bernard
and LeClair's recent paper [1]. Given that the osp(4|4)_(1) WZNW model is a
free theory with power law correlation functions, whereas the su(2)_(0) and
osp(2|2)_(-2) models are CFTs with logarithmic correlation functions, one
immediately wonders whether or not it is possible to combine these logarithms
and obtain simple power laws. Indeed, this very concern has been raised in a
revised version of [1]. In this paper we demonstrate how one may recover the
free field behaviour from a braiding of the solutions of the su(2)_(0) and
osp(2|2)_(-2) Knizhnik-Zamolodchikov equations. We do this by implementing a
procedure analogous to the conformal bootstrap programme [2]. Our ability to
recover such simple behaviour relies on a remarkable identity in the theory of
elliptic integrals known as Legendre's relation.

</DOC>
<DOC>
<DOCNO> 117990 </DOCNO>
Dust lanes, thick absorbers, and the unification model for Seyfert


  A modification of the popular unification model for Seyfert galaxies is
proposed, which takes into account recent observational findings on the
statistical properties of both type 1 and type 2 Seyferts. In the proposed
scenario, Compton-thick Seyfert 2 galaxies are those sources observed through
compact, thick matter (the `torus'), while Compton-thin/intermediate Seyfert
galaxies are obscured by dust lanes at larger distances.

</DOC>
<DOC>
<DOCNO> 119974 </DOCNO>
Soft state of Cygnus X-1: stable disk and unstable corona


  Two component X-ray spectra (soft multicolor black body plus harder power
law) are frequently observed from accreting black holes. These components are
presumably associated with the different parts of the accretion flow (optically
thick and optically thin respectively) in the vicinity of the compact source.
Most of the aperiodic variability of the X-ray flux on the short time scales is
associated with the harder component. We suggest that drastically different
amplitudes of variability of these two components are simply related to the
very different viscous time scales in the geometrically thin and geometrically
thick parts of the accretion flow. In the geometrically thin disks variations
of viscosity or mass accretion rate occurring at large radius from the black
hole on the local dynamical or thermal time scales do not cause any significant
variations of the mass accretion rate at smaller radii due to a very long
diffusion time. Any variations on the time scales shorter than the diffusion
time scale are effectively dampened. On the contrary such variations can easily
survive in the geometrically thick flows and as a result the mass accretion
rate in the innermost region of the flow will reflect modulations of the mass
accretion rate added to the flow at any distance from the black hole. Therefore
if primary instabilities operate on the short time scales then the stability of
the soft component (originating from the geometrically thin and optically thick
flow) and variability of the hard component (coming from the geometrically
thick and optically thin flow) are naturally explained.

</DOC>
<DOC>
<DOCNO> 120825 </DOCNO>
A study of the shadowing of galactic cosmic rays by the sun in a quiet


  We have shown that the Sun's shadow by high energy cosmic rays moves year by
year and its behavior is correlated with a time variation of the large-scale
structure of the solar and interplanetary magnetic fields. The solar activity
was near minimum in the period from 1996 through 1997. Using the data obtained
with the Tibet air shower array, we examined the shadowing of cosmic rays by
the Sun in this quiet phase of solar cycle, and found that the Sun's shadow was
just in the apparent direction of the Sun, though it was observed at the
position considerably away from the Sun to the south-west in the period between
1990 and 1993. It is known that the magnetic pole of equivalent solar dipole
was reversed during the previous active phase, and near solar minimum the
dipole was aligned with the rotating axis, preserving its N-pole on the north
pole side of the Sun. This causes the solar magnetic field to shift the Sun's
shadow to the east. Thus, the observed results suggest that the shift of the
Sun's shadow due to the solar magnetic field was pushed back by the effect of
the geomagnetic field, since the geomagnetic field always make the shadow shift
to the west. We discuss the Sun's shadow observed during the period near solar
minimum in 1996-1997 and compare it with the simulation results.

</DOC>
<DOC>
<DOCNO> 9452 </DOCNO>
Multiscaling at ferromagnetic-spin glass transition point of Random


  We calculate moments of free energy's finite size correction for the
transition point between ferromagnetic and spin glass phases. We find, that
those moments scale with the number of spins with different critical indices,
characteristic for the multiscaling. This critical point corresponds to
threshold of errorless coding for a gaussian noisy channel. We are give the
definition of statistical complexity using this free energy approach.

</DOC>
<DOC>
<DOCNO> 120817 </DOCNO>
User Guide for the Discrete Dipole Approximation Code DDSCAT (Version


  DDSCAT.5a is a freely available software package which applies the "discrete
dipole approximation" (DDA) to calculate scattering and absorption of
electromagnetic waves by targets with arbitrary geometries and complex
refractive index. The DDA approximates the target by an array of polarizable
points. DDSCAT.5a requires that these polarizable points be located on a cubic
lattice. DDSCAT.5a10 allows accurate calculations of electromagnetic scattering
from targets with "size parameters" 2 pi a/lambda < 15 provided the refractive
index m is not large compared to unity (|m-1| < 1).
  The DDSCAT package is written in Fortran and is highly portable. The program
supports calculations for a variety of target geometries (e.g., ellipsoids,
regular tetrahedra, rectangular solids, finite cylinders, hexagonal prisms,
etc.). Target materials may be both inhomogeneous and anisotropic. It is
straightforward for the user to import arbitrary target geometries into the
code, and relatively straightforward to add new target generation capability to
the package. DDSCAT automatically calculates total cross sections for
absorption and scattering and selected elements of the Mueller scattering
intensity matrix for specified orientation of the target relative to the
incident wave, and for specified scattering directions.
  This User Guide explains how to use DDSCAT.5a10 to carry out EM scattering
calculations. CPU and memory requirements are described.

</DOC>
<DOC>
<DOCNO> 9988 </DOCNO>
Violation of general Friedel sum rule in mesoscopic systems


  In the wake of a new kind of phase generally occurring in mesoscopic
transport phenomena, we discuss the validity of Friedel sum rule in the
presence of this phase. We find that the general Friedel sum rule may be
violated.

</DOC>
<DOC>
<DOCNO> 84498 </DOCNO>
Equilibrium sequences of irrotational binary polytropic stars : The case


  Solutions to equilibrium sequences of irrotational binary polytropic stars in
Newtonian gravity are expanded in a power of $\epsilon=a_0/R$, where R and
$a_0$ are the orbital separation of the binary system and the radius of each
star for $R=\infty$. For each order of $\epsilon$, we should solve ordinary
differential equations for arbitrary polytropic indices n. We show solutions
for polytropic indices n= 0.5, 1, 1.5 and 2 up to $\epsilon^6$ orders. Our
semi-analytic solutions can be used to check the validity of numerical
solutions.

</DOC>
<DOC>
<DOCNO> 119251 </DOCNO>
Rapid Optical Followup Observations of SGR Events with ROTSE-I


  In order to observe nearly simultaneous emission from Gamma-ray Bursts
(GRBs), the Robotic Optical Transient Search Experiment (ROTSE) receives
triggers via the GRB Coordinates Network (GCN). Since beginning operations in
March, 1998, ROTSE has also taken useful data for 10 SGR events: 8 from SGR
1900+14 and 2 from SGR 1806-20. We have searched for new or variable sources in
the error regions of these SGRs and no optical counterparts were observed.
Limits are in the range m_ROTSE ~ 12.5 - 15.5 during the period 20 seconds to 1
hour after the observed SGR events.

</DOC>
<DOC>
<DOCNO> 69683 </DOCNO>
Cosmology and Hierarchy in Stabilized Warped Brane Models


  We examine the cosmology and hierarchy of scales in models with branes
immersed in a five-dimensional curved spacetime subject to radion
stabilization. When the radion field is time-independent and the inter-brane
spacing is stabilized, the universe can naturally find itself in the
radiation-dominated epoch. This feature is independent of the form of the
stabilizing potential. We recover the standard Friedmann equations without
assuming a specific form for the bulk energy-momentum tensor. In the models
considered, if the observable brane has positive tension, a solution to the
hierarchy problem requires the presence of a negative tension brane somewhere
in the bulk. We find that the string scale can be as low as the electroweak
scale. In the situation of self-tuning branes where the bulk cosmological
constant is set to zero, the brane tensions have hierarchical values. In the
case of a polynomial stabilizing potential no new hierarchy is created.

</DOC>
<DOC>
<DOCNO> 119689 </DOCNO>
Formation of Cavities, Filaments, and Clumps by the Non-linear


  Based on our high resolution, two-dimensional hydrodynamical simulations, we
propose that large cavities may be formed by the nonlinear development of the
combined thermal and gravitational instabilities, without need for stellar
energy injection in a galaxy modeling the Large Magellanic Clouds (LMC). Our
numerical model of the star formation allows us to follow the evolution of the
blastwaves due to supernovae in the inhomogeous, multi-phase, and
turbulent-like media self-consistently. Formation of kpc-scale inhomogeneity,
such as cavities, observed HI map of the LMC, is suppressed by frequent
supernovae (average supernova rate for the whole disk is ~0.001/yr). However
the supernova explosions are necessary for the hot component (T_g > 10^{6-7}
K). Position-velocity maps show that kpc-scale shells/arcs formed through the
nonlinear evolution in a model without stellar energy feedback has similar
kinematics to explosional phenomena, such as supernovae. We also find that
dense clumps and filamentary structure are formed due to a natural consequence
of the non-linear evolution of the multi-phage ISM. Although the ISM in a small
scale looks turbulent-like and transient, the global structure of the ISM is
quasi-stable. We compare the observations of HI and molecular gas of the LMC
with the numerically obtained HI and CO map. The morphology and statistical
properties of the numerical HI and CO maps are discussed.

</DOC>
<DOC>
<DOCNO> 67996 </DOCNO>
Radion Potential and Brane Dynamics


  We examine the cosmology of the Randall-Sundrum model in a dynamic setting
where scalar fields are present in the bulk as well as the branes. This
generates a mechanism similar to that of Goldberger-Wise for radion
stabilization and the recovery of late-cosmology features in the branes. Due to
the induced radion dynamics, the inflating branes roll towards the minimum of
the radion potential, thereby exiting inflation and reheating the Universe. In
the slow roll part of the potential, the 'TeV' branes have maximum inflation
rate and energy as their coupling to the radion and bulk modes have minimum
suppresion. Hence, when rolling down the steep end of the potential towards the
stable point, the radion field (which appears as the inflaton of the effective
4D theory in the branes) decays very fast, reheats the Universe .This process
results decayin a decrease of brane's canonical vacuum energy $\Lambda_4$.
However, at the minimum of the potential $\Lambda_4$ is small but not
neccessarily zero and the fine-tuning issue remains .Density perturbation
constraints introduce an upper bound when the radion stabilizies. Due to the
large radion mass and strong suppression to the bulk modes, moduli problems and
bulk reheating do not occur. The reheat temperature and a sufficient number of
e-folding constraints for the brane-universe are also satisfied. The model
therefore recovers the radiation dominated FRW universe.

</DOC>
<DOC>
<DOCNO> 11554 </DOCNO>
Impurity Bound States and Symmetry of the Superconducting Order


  Recent experiments on Sr_2RuO_4 have indicated the presence of linear nodes
in the superconducting order parameter. Among the possible spin triplet states,
2D p-wave superconductivity with E_u symmetry appears to be inconsistent with
the experiments, whereas the 2D f-wave order parameter with B_1g x E_u symmetry
turns out to be a more likely candidate. Here it is shown how the
quasi-particle bound state wave functions around a single impurity provide a
clear signature of the symmetry of the underlying superconducting order
parameter.

</DOC>
<DOC>
<DOCNO> 10472 </DOCNO>
Diffusive mass transfer by non equilibrium fluctuations: Fick's law


  Recent experimental and theoretical works have shown that giant fluctuations
are present during diffusion in liquid systems. We use linearized fluctuating
hydrodynamics to calculate the net mass transfer due to these non equilibrium
fluctuations. Surprisingly the mass flow turns out to coincide with the usual
Fick's one. The renormalization of the hydrodynamic equations allows us to
quantify the gravitational modifications of the diffusion coefficient induced
by the gravitational stabilization of long wavelength fluctuations.

</DOC>
<DOC>
<DOCNO> 10968 </DOCNO>
Exact soultion of asymmetric diffusion with second-class particles of


  The exact solution of the asymmetric exclusion problem with particles of
first and second class is presented. In this model the particles (size 1) of
both classes are attached on lattice points and diffuse with equal asymmetric
rates, but particles in the first class do not distinguish those in the second
class from the holes (empty sites). We generalize and solve exactly this model
by considering molecules in the first and second class with sizes $s_1$ and
$s_2$ ($s_1,s_2 = 0,1,2,...$), in units of lattice spacing, respectively. The
solution is derived by a Bethe ansatz of nested type. We give in this paper a
pedagogical and simple presentation of the Bethe ansatz solution of the problem
which can easily be followed by a non specialized audience in exactly
integrable models.

</DOC>
<DOC>
<DOCNO> 119491 </DOCNO>
ROSAT Results on Narrow-Line Seyfert 1 Galaxies


  The excellent soft X-ray sensitivity of the PSPC detector onboard the ROSAT
satellite provided the first chance to study precisely the spectral and timing
properties of Narrow-Line Seyfert 1 galaxies. ROSAT observations of Narrow-Line
Seyfert 1 galaxies have revealed (1) the existence of a giant soft X-ray
excess, (2) a striking, clear correlation between the strength of the soft
X-ray excess emission and the FWHM of the H-beta line, (3) the general absence
of significant soft X-ray absorption by neutral hydrogen above the Galactic
column, (4) short doubling time scales down to about 1000 seconds, (5) the
existence of persistent giant (above a factor of 10), and rapid (less than 1
day) X-ray variability in extragalactic sources. The soft X-ray results on
Narrow-Line Seyfert 1 galaxies indicate that their black hole regions are
directly visible, further supporting the Seyfert 1 nature of these objects. The
extreme X-ray properties of Narrow-Line Seyfert 1 galaxies make them ideal
objects for understanding many of the problems raised generally by the Seyfert
phenomenon.

</DOC>
<DOC>
<DOCNO> 101556 </DOCNO>
On similarity of perturbed multiplication operators


  Let S be the multiplication operator by an independent variable x in L_2(0,1)
and V be an integral operator of Volterra type. We find conditions for T:=S+V
to be similar to S and discuss some generalisations of the results obtained to
an abstract setting.

</DOC>
<DOC>
<DOCNO> 116654 </DOCNO>
Evolution: The Case of the Glyceraldehyde-3-Phosphate Dehydrogenase Gene


  The enzyme Glyceraldehyde-3-Phosphate Dehydrogenase (GAPDH) catalyses the
decomposition of glucose. The gene that produces the GAPDH is therefore present
in a wide class of organisms. We show that for this gene the average value of
the fluctuations in nucleotide distribution in the codons, normalized to strand
bias, provides a reasonable measure of how the gene has evolved in time.

</DOC>
<DOC>
<DOCNO> 116795 </DOCNO>
Re-examination of log-periodicity observed in the seismic precursors of


  Based on several empirical evidence, a series of papers has advocated the
concept that seismicity prior to a large earthquake can be understood in terms
of the statistical physics of a critical phase transition. In this model, the
cumulative Benioff strain (BS) increases as a power-law time-to-failure before
the final event. This power law reflects a kind of scale invariance with
respect to the distance to the critical point. A few years ago, on the basis of
a fit of the cumulative BS released prior to the 1989 Loma Prieta earthquake,
Sornette and Sammis [1995] proposed that this scale invariance could be
partially broken into a discrete scale invariance (DSI). The observable
consequence of DSI takes the form of log-periodic oscillations decorating the
accelerating power law. They found that the quality of the fit and the
predicted time of the event are significantly improved by the introduction of
log-periodicity. Here, we present a battery of synthetic tests performed to
quantify the statistical significance of this claim. We find that log-periodic
oscillations with frequency and regularity similar to those of the Loma Prieta
case are very likely to be generated by the interplay of the low pass filtering
step due to the construction of cumulative functions together with the
approximate power law acceleration. Thus, the single Loma Prieta case alone
cannot support the initial claim and additional cases and further study are
needed to increase the signal-to-noise ratio if any. The present study will be
a useful methodological benchmark for future testing of additional events when
the methodology and data to construct reliable Benioff strain function become
available.

</DOC>
<DOC>
<DOCNO> 70347 </DOCNO>
$b \to s \ell^+ \ell^-$ decays in and beyond the Standard Model


  We briefly review the status of rare radiative and semileptonic $b \to s
(\gamma, \ell^+ \ell^-)$, ($\ell=e,\mu$) decays. We discuss possible signatures
of new physics in these modes and emphazise the role of the exclusive channels.
In particular, measurements of the Forward-Backward asymmetry in $B \to K^*
\ell^+ \ell^-$ decays and its zero provide a clean test of the Standard Model,
complementary to studies in $b \to s \gamma$ decays. Further, the
Forward-Backward CP asymmetry in $B \to K^* \ell^+ \ell^-$ decays is sensitive
to possible non-standard sources of CP violation mediated by flavor changing
neutral current $Z$-penguins.

</DOC>
<DOC>
<DOCNO> 170230 </DOCNO>
Sources of quantum waves


  Due to the space and time dependence of the wave function in the time
dependent Schroedinger equation, different boundary conditions are possible.
The equation is usually solved as an ``initial value problem'', by fixing the
value of the wave function in all space at a given instant. We compare this
standard approach to "source boundary conditions'' that fix the wave at all
times in a given region, in particular at a point in one dimension. In contrast
to the well-known physical interpretation of the initial-value-problem
approach, the interpretation of the source approach has remained unclear, since
it introduces negative energy components, even for ``free motion'', and a
time-dependent norm. This work provides physical meaning to the source method
by finding the link with equivalent initial value problems.

</DOC>
<DOC>
<DOCNO> 101682 </DOCNO>
Multi-Time Dependent Sprays and Harmonic Maps on $J^1(T,M)$


  In this paper are constructed a series of geometrical objects on the 1-jet
fibre bundle $J^1(T,M)$, which is a basic object in the study of classical and
quantum field.

</DOC>
<DOC>
<DOCNO> 9506 </DOCNO>
Quasi-adiabatic Switching for Metal-Island Quantum-dot Cellular Automata


  Recent experiments have demonstrated a working cell suitable for implementing
the Quantum-dot Cellular Automata (QCA) paradigm. These experiments have been
performed using metal island clusters. The most promising approach to QCA
operation involves quasi-adiabatically switching the cells. This has been
analyzed extensively in gated semiconductor cells. Here we present a metal
island cell structure that makes quasi-adiabatic switching possible. We show
how this permits quasi-adiabatic clocking, and enables a pipelined
architecture.

</DOC>
<DOC>
<DOCNO> 69198 </DOCNO>
Predictions for Decays of Radially Excited Baryons


  We consider the strong decays of the lowest-lying radially excited baryons,
in SU(6) language the states comprising the first excited 56-plet. Assuming a
single-quark decay approximation, and negligible configuration mixing, we make
model-independent predictions for the partial decay widths to final states with
a single meson. Masses of unobserved states are predicted using results from
large-N_c QCD, and the momentum dependence of the one-body decay amplitude is
determined phenomenologically by fitting to observed decays, so that the baryon
spatial wave functions are not assumed. We point out that comparison of these
predictions to experiment may shed light on whether the Roper resonance can be
consistently interpreted as a three-quark state.

</DOC>
<DOC>
<DOCNO> 11872 </DOCNO>
Josephson-Vortex-Glass Transition in Strong Fields


  A vortex-glass transition due to point disorder in layered superconductors is
studied for the case with an applied field {\it parallel} to the layers. Our
calculation of tilt responses indicates that, irrespective of the magnitude of
the field, the resulting glass phase, Josephson-vortex-glass (JG), should have
a transverse Meissner effect, as in a planar splayed glass phase, only for a
tilt perpendicular to the layers. Further, focusing on the high field (and/or
high anisotropy) region $B \sqrt{\Gamma} > \phi_0/d^2$, where $\Gamma$ is the
mass anisotropy in the Lawrence-Doniach model, the JG transition line
$T_{JG}(B)$ is shown to have a similar form to a $B$-$T$ line following from
the {\it disorder-free} Lindemann criterion and to decrease with increasing $B
\sqrt{\Gamma}$, in marked contrast to the disorder-free melting line {\it
insensitive to} $B \sqrt{\Gamma}$ in such the high field region. This
$T_{JG}(B)$ line seems to have been recently observed in a.c. susceptibility
and in-plane resistivity measurements in BSCCO and qualitatively explains a
field dependence at lower temperatures of previous BSCCO resistivity data
showing the so-called in-plane Lorentz force-free behavior.

</DOC>
<DOC>
<DOCNO> 10092 </DOCNO>
Measurement of the angular momentum of a rotating Bose-Einstein


  We study the quadrupole oscillation of a Bose-Einstein condensate of
$^{87}$Rb atoms confined in an axisymmetric magnetic trap, after it has been
stirred by an auxiliary laser beam. The stirring may lead to the nucleation of
one or more vortices, whose presence is revealed unambiguously by the
precession of the axes of the quadrupolar mode. For a stirring frequency
$\Omega$ below the single vortex nucleation threshold $\Omega_c$, no measurable
precession occurs. Just above $\Omega_c$, the angular momentum deduced from the
precession is $\sim \hbar$. For stirring frequencies above $\Omega_c$ the
angular momentum is a smooth and increasing function of $\Omega$, until an
angular frequency $\Omega_c'$ is reached at which the vortex lattice disappears
and the precession stops.

</DOC>
<DOC>
<DOCNO> 100116 </DOCNO>
Combinatorics and Quotients of Toric Varieties


  This paper studies two related subjects. One is some combinatorics arising
from linear projections of polytopes and fans of cones. The other is quotient
varieties of toric varieties. The relation is that projections of polytopes are
related to quotients of projective toric varieties and projection of fans are
related to quotients of general toric varieties. Despite its relation to
geometry the first part is purely combinatorial and should be of interest in
its own right.

</DOC>
<DOC>
<DOCNO> 151716 </DOCNO>
Non-commutative Soliton Scattering


  We study solitons in three dimensional non-commutative scalar field theory at
infinite non-commutativity parameter. We find the metric on the relative moduli
space of all solitons of the form |n><n| and show that it is Kahler. We then
find the geodesics of this metric and study the scattering of these solitons.
In particular we find that the scattering is generally right angle for small
values of the impact parameter. We can understand this behaviour in terms of a
conical singularity at the origin of moduli space.

</DOC>
<DOC>
<DOCNO> 40423 </DOCNO>
Dijet Production in Charged and Neutral Current e^+p Interactions at


  Jet production in charged and neutral current events in the kinematic range
of Q^2 from 640 to 35000 GeV^2 is studied in deep-inelastic positron-proton
scattering at HERA. The measured rate of multi-jet events and distributions of
jet polar angle, transverse energy, dijet mass, and other dijet variables are
presented. Using parton densities derived from inclusive DIS cross sections,
perturbative QCD calculations in NLO are found to give a consistent description
of both the neutral and charged current dijet production. A direct, model
independent comparison of the jet distributions in charged and neutral current
events confirms that the QCD dynamics of the hadronic final state is
independent of the underlying electroweak scattering process.

</DOC>
<DOC>
<DOCNO> 84156 </DOCNO>
The Bisognano-Wichmann Theorem for Charged States and the Conformal


  Recent applications of Operator Algebras to Quantum Field Theory on a Curved
Spacetime show that the incremental entropy associated with a quantum black
hole, due the addition of a short range charge, is quantized proportionally to
the logarithm of an integer. This talk first reviews the case of a Rindler
black hole and then sketches the case of a spacetime with bifurcate Killing
horizon and charges localizable on the horizon. An important tool is the
construction of the conformal symmetries on the horizon.

</DOC>
<DOC>
<DOCNO> 150531 </DOCNO>
A Note on the Holographic Beta and C Functions


  The holographic RG flow in AdS/CFT correspondence naturally defines a
holographic scheme in which the central charge c and the beta function are
related by a universal formula. We perform some checks of that formula and we
compare it with quantum field theory expectations. We discuss alternative
definitions of the c-function. In particular, we compare, for a particular
supersymmetric flow, the holographic c-function with the central charge
computed directly from the two-point function of the stress-energy tensor.

</DOC>
<DOC>
<DOCNO> 69608 </DOCNO>
Event-by-event fluctuations of the charged particle ratio from


  The event by event fluctuations of the ratio of positively to negatively
charged hadrons are predicted within the UrQMD model. Corrections for finite
acceptance and finite net charge are derived. These corrections are relevant to
compare experimental data and transport model results to previous predictions.
The calculated fluctuations at RHIC and SPS energies are shown to be compatible
with a hadron gas. Thus, deviating by a factor of 3 from the predictions for a
thermalized quark-gluon plasma.

</DOC>
<DOC>
<DOCNO> 150357 </DOCNO>
Twistors and Actions on Coset Manifolds


  Particle and string actions on coset spaces typically lack a quadratic
kinetic term, making their quantization difficult. We define a notion of
twistors on these spaces, which are hypersurfaces in a vector space that
transform linearly under the isometry group of the coset. By associating the
points of the coset space with these hypersurfaces, and the internal
coordinates of these hypersurfaces with momenta, it is possible to construct
manifestly symmetric actions with leading quadratic terms. We give a general
algorithm and work out the case of a particle on AdS_p explicitly. In this
case, the resulting action is a world-line gauge theory with sources, (the
gauge group depending on p) which is equivalent to a nonlocal world-line
sigma-model.

</DOC>
<DOC>
<DOCNO> 67855 </DOCNO>
Test of the QCD vacuum with the sources in higher representations


  Recent accurate measurement by G.Bali of static potentials between sources in
various SU(3) representations provides a crucial test of the QCD vacuum and of
different theoretical approaches to the confinement. In particular, the Casimir
scaling of static potentials found for all measured distances implies a strong
suppression of higher cumulants and a high accuracy of the Gaussian stochastic
vacuum. Most popular models are in conflict with these measurements.

</DOC>
<DOC>
<DOCNO> 120986 </DOCNO>
Radio Halos of Galaxy Clusters from Hadronic Secondary Electron


  We investigate the possibility that radio halos of clusters of galaxies are
caused by synchrotron emission of cosmic ray electrons (CRe), which were
produced by cosmic ray protons (CRp) interacting hadronically with the
intra-cluster medium (ICM) protons. We perform cosmological
magneto-hydrodynamics (MHD) simulations to obtain a sample of ten magnetized
galaxy clusters. They provide realistic models of the gas and magnetic field
distribution, needed to predict the CRe production rates, their cooling, and
their synchrotron emissivity. We assume a CRp population within the ICM with an
energy density which has a constant ratio to thermal energy density. This ratio
is adjusted in such a way that one of the simulated clusters reproduces the
radio luminosity of the radio halo of the Coma cluster of galaxies. Our model
exhibits the observed low degree of radio polarization and has a similar radial
emission profile as the Coma cluster. We provide estimates for the expected
gamma ray and neutrino flux. The necessary CRp/thermal energy ratio is 4 ...
14% ${(E_{p,min}/GeV)}^{-0.375}$ (for the range of magnetic field strengths
suggested by Faraday measurements), where $E_{p,min}$ is the lower kinetic
energy cutoff of the CRp with spectral index $\alpha_p \approx 2.375$. Assuming
this ratio to be the same in the whole set of simulated clusters a $T_x-L_\nu$
relation is predicted which follows the observed relation well.

</DOC>
<DOC>
<DOCNO> 10397 </DOCNO>
Localization of eigenstates in a modified Tomonaga-Luttinger model


  We study the localization in the Hilbert space of a modified
Tomonaga-Luttinger model. For the standard version of this model, the states
are found to be extended in the basis of Slater determinants, representing the
eigenstates of the non-interacting system. The linear dispersion which leads to
the fact that these eigenstates are extended in the modified model is replaced
by one with random level spacings modeling the complicated one-particle spectra
of realistic models. The localization properties of the eigenstates are
studied. The interactions are simplified and an effective one-dimensional Lloyd
model is obtained. The effects of many-body energy correlations are studied
numerically. The eigenstates of the system are found to be localized in Fock
space for any strength of the interactions, but the localization is not
exponential.

</DOC>
<DOC>
<DOCNO> 116649 </DOCNO>
Issues in Quantized Fractal Space Time


  In recent years, the picture of discrete space time has been studied in the
context of stochastic theory. There are a number of ramifications, which are
briefly examined. We argue that the causality of physiics has its roots in the
analyticity within the two dimensons of a fractal quantum path and further show
how this picture has convergence wth quantum superstrings.

</DOC>
<DOC>
<DOCNO> 9180 </DOCNO>
On the Possible Instability of the Lattice of Layered Conductors Due to


  In this paper we study theoretically how the local geometry of the Fermi
surface (FS) of a layered conductor can affect quantum oscillations in the
thermodynamic observables. We introduce a concrete model of the FS of a layered
conductor. The model permits us to analyze the characteristic features of
quantum oscillatory phenomena in these materials which occure due to local
anomalies of the Gaussian curvature of the FS. Our analysis takes into account
strong interaction among quasiparticles and we study the effect of this
interaction within the framework of Fermi-liquid theory. We show that the
Fermi-liquid interaction strongly affects the density of states of
quasiparticles (DOS) on the FS. As a result DOS can have singularities near the
peaks of its oscillations in a strong magnetic field. These singularities can
be significantly strengthened when the FS of the layered conductor is locally
flattened. This can lead to magnetic and lattice instabilities of a special
kind which are considered in the final part of the work.

</DOC>
<DOC>
<DOCNO> 117971 </DOCNO>
Abundances of light elements in metal-poor stars. III. Data analysis and


  We present the analysis of an extensive set of new and literature high
quality data concerning Fe, C, N, O, Na, and Mg, exploiting the Teff scale
determined in Gratton et al. (1996), and the non-LTE abundance corrections
computed in Gratton et al. (1999). Results obtained with various abundance
indices are discussed and compared. Our non-LTE analysis yields the same O
abundances from both permitted and forbidden lines for stars with Teff>4600 K,
in agreement with King (1993), but not with other studies using a lower
Teff-scale for subdwarfs. However we obtain slightly smaller O abundances for
the most luminous metal poor field stars than for fainter stars of similar
metallicities, an effect attributed to inadequacies of the adopted model
atmospheres (Kurucz 1992, with overshooting) for cool stars. We find a nearly
constant O overundance in metal poor stars ([Fe/H]<-0.8), at a mean value of
0.46+-0.02 dex (sigma=0.12, 32 stars), with only a gentle slope with [Fe/H] (~
-0.1); this result is different from the steeper slope recently obtained using
OH band in the near UV. If only 'bonafide' unmixed stars are considered, C
abundances scale with Fe ones (i.e. [C/Fe]~ 0) down to [Fe/H]~ -2.5. Due to our
adoption of a different Teff-scale, we do not confirm the slight C excess in
the most metal poor disk dwarfs (-0.8<[Fe/H]<-0.4) found in previous studies.
Na abundances scale as Fe ones in the high metallicity regime, while metal-poor
stars present a Na underabundance. None of the field stars analyzed belong to
the group of O-poor and Na-rich stars observed in globular clusters. Na is
deficient with respect to Mg in halo and thick disk stars; within these
populations, Na deficiency may be a slow function of [Mg/H]. Solar [Na/Mg]
ratios are obtained for thin disk stars.

</DOC>
<DOC>
<DOCNO> 8143 </DOCNO>
Transient Dynamics of Pinning


  We study the evolution of an elastic string into the pinned state at driving
forces slightly below the depinning threshold force $F_c$. We quantify the
temporal evolution of the string by an {\it activity function} $A(t)$
representing the fraction of active nodes at time $t$ and find three distinct
dynamic regimes. There is an initial stage of fast decay of the activity; in
the second, intermediate, regime, an exponential decay of activity is observed;
and, eventually, the fast collapse of the string towards its final pinned state
results in an decay in the activity with $\Am \sim (t_p-t)^{\psi}$, where $t_p$
is the pinning time in the finite system involved.

</DOC>
<DOC>
<DOCNO> 102299 </DOCNO>
Homological mirror symmetry and torus fibrations


  In this paper we discuss two major conjectures in Mirror Symmetry:
Strominger-Yau-Zaslow conjecture about torus fibrations, and the homological
mirror conjecture (about an equivalence of the Fukaya category of a Calabi-Yau
manifold and the derived category of coherent sheaves on the dual Calabi-Yau
manifold). Our point of view on the origin of torus fibrations is based on the
standard differential-geometric picture of collapsing Riemannian manifolds as
well as analogous considerations for Conformal Field Theories. It seems to give
a description of mirror manifolds much more transparent than the one in terms
of D-branes.
  Also we make an attempt to prove the homological mirror conjecture using the
torus fibrations. In the case of abelian varieties, and for a large class of
Lagrangian submanifolds, we obtain an identification of Massey products on the
symplectic and holomorphic sides. Tools used in the proof are of a mixed
origin: not so classical Morse theory, homological perturbation theory and
non-archimedean analysis.

</DOC>
<DOC>
<DOCNO> 71059 </DOCNO>
Searching Saturation in eA Processes


  The high density effects should be manifest at small x and/or large nuclei.
In this letter we consider the behavior of nuclear structure function $F_2^A$
slope in the kinematic region which could be explored in the future eA
colliders as a search of these effects. We verify that the high density implies
that the maximum value of the slope occurs at large values of the photon
virtuality, i.e. in a perturbative regime, and is dependent of the number of
nucleons A and energy. Our conclusion is that the measurement of this
observable will allow to explicit the saturation.

</DOC>
<DOC>
<DOCNO> 122889 </DOCNO>
On the pre-RLO spin-orbit couplings in LMXBs


  We investigate the effect of orbital decay caused by nuclear expansion of a
(sub)giant star in synchronous binary system. We compare this effect with the
presence of a magnetic stellar wind and show that the additional transfer of
orbital angular momentum into spin angular momentum is relatively important --
especially since it has been shown that the effect of magnetic braking
saturates at short orbital periods.

</DOC>
<DOC>
<DOCNO> 70853 </DOCNO>
Candidates for HyperCharge Axion in Extensions of the Standard Model


  Many theoretically well-motivated extensions of the Standard Model contain
heavy pseudoscalars that couple to hypercharge topological density. The
cosmological dynamics of such hypercharge axions could, under certain
conditions, lead to generation of a net baryon number in a sufficient amount to
explain the observed baryon asymmetry in the universe. We examine the Minimal
Supersymmetric Standard Model and string/M-theory models and determine specific
conditions which heavy axion-like pseudoscalars must satisfy to successfully
drive baryogenesis. We find that all candidates in the Minimal Supersymmetric
Standard Model fail to obey some of the constraints, and that only in special
string/M-theory models some axions may be adequate.

</DOC>
<DOC>
<DOCNO> 119896 </DOCNO>
The Physical Conditions of the X-ray Emission Line Regions in the


  We present a detailed X-ray spectral analysis of the Circinus Galaxy using
archival data obtained with the ASCA satellite. The spectrum shows numerous
emission lines in the soft X-ray band from highly ionized ions, as well as
Compton reflection and fluorescent lines from neutral or near-neutral matter.
We analyze the spectrum in the context of a self-consistent recombination
cascade model and find that a nearly flat differential emission measure (DEM)
distribution in ionization parameter fits the data. For a fixed solid angle
distribution of matter surrounding a point source, this corresponds to a run of
electron density of the form, n(r) ~ r^(-3/2), which is suggestive of Bondi
accretion onto a central compact mass. Using this density profile and comparing
the resulting emission spectra with the ASCA data, the size of the X-ray
emission line region is estimated to be < 1 kpc. We also show that the derived
density as a function of radius is compatible with the X-ray recombination line
emission region being the confining medium of the coronal line regions.

</DOC>
<DOC>
<DOCNO> 122771 </DOCNO>
The boron absorption line at 2089.6 AA in HD 140283 ?


  We have observed the B I line at 2089.6 AA in the metal poor star HD 140283
with HST/STIS. The observation was an attempt to confirm the B abundances
derived from the 2497 AA B I line in earlier works in general, and for for this
star in particular (Edvardsson et al. 1994 A&A 290, 176; Kiselman & Carlsson
1996, A&A 311, 680). The resulting spectrum gained from 8 orbits of
observations is hardly consistent with the boron abundance derived in the
earlier works. A pure 10^B line could produce the feature observed but no
reasonable process can produce such a ratio between 10^B and 11^B. More likely
the analysed feature is affected by a statistical fluctuation. A conservative
upper limit estimate of the NLTE corrected boron abundance gives a value
marginally consistent with that derived from the 2497 AA line. We are proposing
further observations to derive a more definite abundance from the line.

</DOC>
<DOC>
<DOCNO> 70862 </DOCNO>
High Energy Neutrinos From Superheavy Dark Matter Annihilation


  Superheavy ($M>10^{10}$ GeV) particles produced during inflation may be the
dark matter, independent of their interaction strength. Strongly interacting
superheavy particles will be captured by the sun, and their annihilation in the
center of the sun will produce a flux of energetic neutrinos that should be
detectable by neutrino telescopes. Depending on the particle mass, event rates
in a cubic-kilometer detector range from several per hour to several per year.
The signature of the process is a predominance of tau neutrinos, with a
relatively flat energy spectrum of events ranging from 50 GeV to many TeV, and
with the mean energy of detected tau neutrinos about 3 TeV.

</DOC>
<DOC>
<DOCNO> 84641 </DOCNO>
Generalized Bowen--York Initial Data


  A class of vacuum initial-data sets is described which are based on certain
expressions for the extrinsic curvature first studied and employed by Bowen and
York. These expressions play a role for the momentum constraint of general
relativity which is analogous to the role played by the Coulomb solution for
the Gauss-law constraint of electromagnetism.

</DOC>
<DOC>
<DOCNO> 69624 </DOCNO>
QCD Analysis of Structure Functions of Real and Virtual Photons


  Parameter-free and perturbatively stable leading order (LO) and
next-to-leading order (NLO) parton densities for real and virtual photons are
presented.

</DOC>
<DOC>
<DOCNO> 120670 </DOCNO>
Star Formation Efficiency in the Central 1 kpc Region of Early-Type


  It has been reported recently that there are some early-type spiral (Sa--Sab)
galaxies having evident star-forming regions which concentrate in their own
central 1-kpc. In such central region, is the mechanism of the star formation
distinct from that in disks of spiral galaxies? To reveal this, we estimate the
star formation efficiency (SFE) in this central 1-kpc star-forming region of
some early-type spiral galaxies, taking account of the condition for this 1-kpc
region to be self-gravitating. Using two indicators of present star formation
rate (H$\alpha$ and infrared luminosity), we estimate the SFE to be a few
percents. This is equivalent to the observational SFE in the disks of late-type
spiral (Sb--) galaxies. This coincidence may support the universality of the
mean SFE of spiral galaxies reported in the recent studies. That is, we find no
evidence of distinct mechanism of the star formation in the central 1-kpc
region of early-type galaxies. Also, we examine the structure of the central
star-forming region, and discuss a method for estimating the mass of
star-forming regions.

</DOC>
<DOC>
<DOCNO> 68807 </DOCNO>
Quantization of Four-form Fluxes and Dynamical Neutralization of the


  A four-form gauge flux makes a variable contribution to the cosmological
constant. This has often been assumed to take continuous values, but we argue
that it has a generalized Dirac quantization condition. For a single flux the
steps are much larger than the observational limit, but we show that with
multiple fluxes the allowed values can form a sufficiently dense `discretuum'.
Multiple fluxes generally arise in M theory compactifications on manifolds with
non-trivial three-cycles. In theories with large extra dimensions a few
four-forms suffice; otherwise of order 100 are needed. Starting from generic
initial conditions, the repeated nucleation of membranes dynamically generates
regions with a cosmological constant in the observational range. Entropy and
density perturbations can be produced.

</DOC>
<DOC>
<DOCNO> 151850 </DOCNO>
Localization of supergravity on the brane


  A supersymmetric Randall-Sundrum brane-world demands that not merely the
graviton but the entire supergravity multiplet be trapped on the brane. To
demonstrate this, we present a complete ansatz for the reduction of (D=5,N=4)
gauged supergravity to (D=4,N=2) ungauged supergravity in the Randall-Sundrum
geometry. We verify that it is consistent to lowest order in fermion terms. In
particular, we show how the graviphotons avoid the `no photons on the brane'
result because they do not originate from Maxwell's equations in D=5 but rather
from odd-dimensional self-duality equations. In the case of the fivebrane, the
Randall-Sundrum mechanism also provides a new Kaluza-Klein way of obtaining
chiral supergravity starting from non-chiral.

</DOC>
<DOC>
<DOCNO> 68430 </DOCNO>
Dual-Resonance Model and Multiple Production


  The very high multiplicity (VHM) processes are considered to investigate
consequences of the dual resonance models reach (exponential) mass spectrum.
The virial decomposition is developed for description of the produced particles
short-rang (resonance) correlations. It is shown that the reach mass spectrum
is able to do more flat the VHM distribution: $\s_n=O(e^{-n})$ up to
multiplicities $n\simeq\bar{n}^2$, $\bar{n}$ is the mean multiplicity. But for
$n>>\bar{n}^2$ one should expect $\s_n<O(e^{-n})$.

</DOC>
<DOC>
<DOCNO> 85462 </DOCNO>
Fluctuations in the current and energy densities around a magnetic flux


  We calculate the fluctuations in the current and energy densities for the
case of a quantized, minimally coupled, massless, complex scalar field around a
straight and infinitesimally thin cosmic string carrying magnetic flux. At zero
temperature, we evaluate the fluctuations in the current and energy densities
for arbitrary flux and deficit angle. At a finite temperature, we evaluate the
fluctuations in the energy density for the special case wherein the flux is
absent and the deficit angle equals $\pi$. We find that, quite generically, the
dimensionless ratio of the variance to the mean-squared values of the current
and energy densities are of order unity which suggests that the fluctuations
around cosmic strings can be considered to be large.

</DOC>
<DOC>
<DOCNO> 69569 </DOCNO>
Inflation and Supersymmetry Breaking


  We study the connection between inflation and supersymmetry breaking in the
context of an O'Raifeartaigh model which can account for both hybrid inflation
and a true vacuum where supersymmetry is spontaneously broken. For a weakly
coupled inflaton field, the dynamics during the inflationary phase can be
determined by the supersymmetry breaking scale $M_S\sim 10^{10}$ GeV, even if
$H_I >> m_{3/2}$. The spectrum of density fluctuations is then almost scale
invariant, with a spectral index $n-1={\cal O}(M_G^2/M_P^2)$. The mass
parameter $M_G$ of the O'Raifeartaigh model is determined by the COBE
normalization for the cosmic microwave background to be the grand unification
scale, $M_G \sim 10^{16}$ GeV.

</DOC>
<DOC>
<DOCNO> 70108 </DOCNO>
Supersymmetry in Singular Spaces


  We develop the concept of supersymmetry in singular spaces, apply it in an
example for 3-branes in D=5 and comment on 8-branes in D=10. The new
construction has an interpretation that the brane is a sink for the flux and
requires adding to the standard supergravity a (D-1)-form field and a
supersymmetry singlet field. This allows a consistent definition of
supersymmetry on a S_1/Z_2 orbifold, the bulk and the brane actions being
separately supersymmetric. Randall-Sundrum brane-worlds can be reproduced in
this framework without fine tuning. For fixed scalars, the doubling of unbroken
supersymmetries takes place and the negative tension brane can be pushed to
infinity. In more general BPS domain walls with 1/2 of unbroken
supersymmetries, the distance between branes in some cases may be restricted by
the collapsing cycles of the Calabi-Yau manifold. The energy of any static
x^5-dependent bosonic configuration vanishes, E=0, in analogy with the
vanishing of the Hamiltonian in a closed universe.

</DOC>
<DOC>
<DOCNO> 101188 </DOCNO>
Dimensions of Prym Varieties


  Given a tame Galois branched cover of curves pi: X -> Y with any finite
Galois group G whose representations are rational, we compute the dimension of
the (generalized) Prym variety corresponding to any irreducible representation
\rho of G. This formula can be applied to the study of algebraic integrable
systems using Lax pairs, in particular systems associated with Seiberg-Witten
theory. However, the formula is much more general and its computation and proof
are entirely algebraic.

</DOC>
<DOC>
<DOCNO> 151358 </DOCNO>
RG-flows and Open/Closed String Duality


  We discuss the interpaly between IR and UV divergences in theories with open
and unoriented strings in view of the AdS/CFT correspondence. We start by
deriving general formulas for the computation of threshold corrections to gauge
couplings in generic configurations with open and unoriented strings. These
allow us to discuss the IR/UV correspondence between beta-function coefficients
and ``dilaton'' tadpoles for several brane configurations probed by D3-branes.
Finally we comment on the AdS supergravity descriptions of gauge theories that
are (super)conformal in the large N limit.

</DOC>
<DOC>
<DOCNO> 123148 </DOCNO>
M31's molecular arms at all scales to below 10pc


  I present a unique data set for the study of molecular gas in galaxies: a
complete, high-resolution survey of the CO in M31 and additional local studies.
The fully sampled survey has an angular resolution of 23" FWHM and the
interferometric data attain the pc-scale with sub-arcsecond resolution. For the
first time it is now possible to study large and small scales in conjunction.
Thus we are able to derive the global structure and study the links down to the
individual cloud complexes and star formation regions.

</DOC>
<DOC>
<DOCNO> 7814 </DOCNO>
Drift-Controlled Anomalous Diffusion: A Solvable Gaussian Model


  We introduce a Langevin equation characterized by a time dependent drift. By
assuming a temporal power-law dependence of the drift we show that a great
variety of behavior is observed in the dynamics of the variance of the process.
In particular diffusive, subdiffusive, superdiffusive and stretched
exponentially diffusive processes are described by this model for specific
values of the two control parameters. The model is also investigated in the
presence of an external harmonic potential. We prove that the relaxation to the
stationary solution is power-law in time with an exponent controlled by one of
model parameters.

</DOC>
<DOC>
<DOCNO> 150369 </DOCNO>
The commutativity principle and lagrangian symmetries


  Using the commutativity of a general variation with the time differentiation
we discuss both global and local (gauge) symmetries of a lagrangian from a
unified point of view. The Noether considerations are thereby applicable for
both cases. A complete equivalence between the hamiltonian and lagrangian
formulations is established.

</DOC>
<DOC>
<DOCNO> 116656 </DOCNO>
Experimental evidence of dynamical localization and delocalization in a


  This paper presents the first experimental evidence of the transition from
dynamical localization to delocalization under the influence of a
quasi-periodic driving on a quantum system. A quantum kicked rotator is
realized by placing cold atoms in a pulsed, far-detuned, standing wave. If the
standing wave is periodically pulsed, one observes the suppression of the
classical chaotic diffusion, i.e. dynamical localization. If the standing wave
is pulsed quasi-periodically with two different frequencies, dynamical
localization is observed or not, depending on the two frequencies being
commensurable or incommensurable. One can thus study the transition from the
localized to the delocalized case as a function of the effective dimensionality
of the system.

</DOC>
<DOC>
<DOCNO> 85302 </DOCNO>
Diffeomorphism Invariant Theories and Vector Supersymmetry


  Einstein gravity in the Palatini first order formalism is shown to possess a
vector supersymmetry of the type encountered in the topological gauge theories.
A peculiar feature of the gravitationel theory is the link of this vector
supersymmetry with the field equation of motion of the Faddeev-Popov ghost
associated to diffeomorphism invariance.

</DOC>
<DOC>
<DOCNO> 152444 </DOCNO>
An M-theory Flop as a Large N Duality


  We show how a recently proposed large $N$ duality in the context of type IIA
strings with ${\cal N}=1$ supersymmetry in 4 dimensions can be derived from
purely geometric considerations by embedding type IIA strings in M-theory. The
phase structure of M-theory on $G_2$ holonomy manifolds and an $S^3$ flop are
the key ingredients in this derivation.

</DOC>
<DOC>
<DOCNO> 70272 </DOCNO>
The Lower Bound on the Neutralino-Nucleon Cross Section


  We examine if there is a lower bound on the direct detection cross section
for the neutralino dark matter in the MSSM. If we impose the minimal
supergravity boundary conditions as well as the "naturalness" condition, in
particular m_{1/2} < 300 GeV, we show that there is a lower bound of
10^{-46}cm^2 on the cross section for neutralino scattering off of a proton. We
also clarify the origin for the lower bound. Relaxing either of the
assumptions, however, can lead to much smaller cross sections.

</DOC>
<DOC>
<DOCNO> 84511 </DOCNO>
Quintessence and Scalar Dark Matter in the Universe


  Continuing with previous works, we present a cosmological model in which dark
matter and dark energy are modeled by scalar fields $\Phi $ and $\Psi$,
respectively, endowed with the scalar potentials $V(\Phi)=V_{o}[ \cosh
{(\lambda \sqrt{\kappa_{o}}\Phi)}-1] $ and $\tilde{V}(\Psi)=\tilde{V_{o}}[
\sinh {(\alpha \sqrt{\kappa_{o}}\Psi)}] ^{\beta}$. This model contains 95% of
scalar field. We obtain that the scalar dark matter mass is $m_{\Phi}\sim
10^{-26}eV.$ The solution obtained allows us to recover the success of the
standard CDM. The implications on the formation of structure are reviewed. We
obtain that the minimal cutoff radio for this model is $r_{c}\sim 1.2 kpc.$

</DOC>
<DOC>
<DOCNO> 101353 </DOCNO>
Howe Duality for Lie Superalgebras


  We study a dual pair of general linear Lie superalgebras in the sense of R.
Howe. We give an explicit multiplicity-free decomposition of a symmetric and
skew-symmetric algebra (in the super sense) under the action of the dual pair
and present explicit formulas for the highest weight vectors in each isotypic
subspace of the symmetric algebra. We give an explicit multiplicity-free
decomposition into irreducible $gl(m|n)$-modules of the symmetric and
skew-symmetric algebras of the symmetric square of the natural representation
of $gl(m|n)$. In the former case we find as well explicit formulas for the
highest weight vectors. Our work unifies and generalizes the classical results
in symmetric and skew-symmetric models and admits several applications.

</DOC>
<DOC>
<DOCNO> 83194 </DOCNO>
Cluster Computing White Paper


  Cluster computing is not a new area of computing. It is, however, evident
that there is a growing interest in its usage in all areas where applications
have traditionally used parallel or distributed computing platforms. The
growing interest has been fuelled in part by the availability of powerful
microprocessors and high-speed networks as off-the-shelf commodity components
as well as in part by the rapidly maturing software components available to
support high performance and high availability applications.
  This White Paper has been broken down into eleven sections, each of which has
been put together by academics and industrial researchers who are both experts
in their fields and where willing to volunteer their time and effort to put
together this White Paper. The status of this paper is draft and we are at the
stage of publicizing its presence and making a Request For Comments (RFC).

</DOC>
<DOC>
<DOCNO> 10280 </DOCNO>
Effects of Boson Dispersion in Fermion-Boson Coupled Systems


  We study the nonlinear feedback in a fermion-boson system using an extension
of dynamical mean-field theory and the quantum Monte Carlo method. In the
perturbative regimes (weak-coupling and atomic limits) the effective
interaction among fermions increases as the width of the boson dispersion
increases. In the strong coupling regime away from the anti-adiabatic limit,
the effective interaction decreases as we increase the width of the boson
dispersion. This behavior is closely related with complete softening of the
boson field. We elucidate the parameters that control this nonperturbative
region where fluctuations of the dispersive bosons enhance the delocalization
of fermions.

</DOC>
<DOC>
<DOCNO> 8860 </DOCNO>
Quantum suppression of superconductivity in ultrathin nanowires


  We report measurements on ultrathin (<10 nm) nanowires produced by coating
carbon nanotubes with a superconducting amorphous MoGe alloy. We find that
nanowires can be superconducting or insulating depending on their normal state
resistance $R_{N}$ compared to $R_{q}=h/(2e)^{2}$ -- the quantum resistance for
Cooper pairs. If $R_{N}< R_{q}$ the tunneling of quantum phase slips (QPS) is
prohibited due to strong damping, and so the wires stay superconducting. The
insulating state, observed if $R_{N}> R_{q}$, is explained in terms of
proliferation of quantum phase slips and corresponding localization of Cooper
pairs. The observed superconductor-insulator transition is analogous to the
dissipative phase transition which takes place in Josephson Junctions at
$R_{N}= R_{q}$ (Penttila et al., Phys. Rev. Lett. Vol.82, p.1004, 1999)

</DOC>
<DOC>
<DOCNO> 120806 </DOCNO>
A Deep ROSAT HRI Observation of NGC 1313


  We describe a series of observations of NGC 1313 using the ROSAT HRI with a
combined exposure time of 183.5 ksec. The observations span an interval between
1992 and 1998; the purpose of observations since 1994 was to monitor the X-ray
flux of SN1978K, one of several luminous sources in the galaxy. No diffuse
emission is detected in the galaxy to a level of ~1-2x10^37 ergs/s/arcmin^-2. A
total of eight sources are detected in the summed image within the D_25
diameter of the galaxy. The luminosities of five of the eight range from
\~6x10^37 to ~6x10^38 erg/s; these sources are most likely accreting X-ray
binaries, similar to sources obseved in M31 and M33. The remaining three
sources all emit above 10^39 erg/s. We present light curves of the five
brightest sources. Variability is detected at the 99.9% level from four of
these. We identify one of the sources as an NGC 1313 counterpart of a Galactic
X-ray source. The light curve, though crudely sampled, most closely resembles
that of a Galactic black hole candidate such as GX339-4, but with considerably
higher peak X-ray luminosity. An additional seven sources lie outside of the
D_25 diameter and are either foreground stars or background AGN.

</DOC>
<DOC>
<DOCNO> 11057 </DOCNO>
Orbital and spin Kondo effects in a double quantum dot


  Motivated by recent experiments, in which the Kondo effect has been observed
for the first time in a double quantum-dot structure, we study electron
transport through a system consisting of two ultrasmall, capacitively-coupled
dots with large level spacing and charging energy. Due to strong interdot
Coulomb correlations, the Kondo effect has two possible sources, the spin and
orbital degeneracies, and it is maximized when both occur simultaneously. The
large number of tunable parameters allows a range of manipulations of the Kondo
physics -- in particular, the Kondo effect in each dot is sensitive to changes
in the state of the other dot. For a thorough account of the system dynamics,
the linear and nonlinear conductance is calculated in perturbative and
non-perturbative approaches. In addition, the temperature dependence of the
resonant peak heights is evaluated in the framework of a renormalization group
analysis.

</DOC>
<DOC>
<DOCNO> 123286 </DOCNO>
Present Status of Diffusive Shock Acceleration


  Diffusive shock acceleration (DSA) is now widely accepted as the model to
explain the production of cosmic rays (CRs) in a wide range of astrophysical
environments. Despite initial successes of the theory in explaining the
energetics and the spectrum of CRs accelerated by supernova remnants, there
still remain some unresolved issues such as particle injection out of the
thermal plasma at shocks, CR diffusion due to the self-generated MHD waves and
yet-to-be-detected gamma-ray emission due to the ionic CRs. Recent technical
advancements to resolve these issues are reviewed.

</DOC>
<DOC>
<DOCNO> 72150 </DOCNO>
Zweig rule violation in the scalar sector and values of low-energy


  We discuss the role of the Zweig rule violation in the scalar channel for the
determination of low-energy constants and condensates arising in the effective
chiral Lagrangian of QCD. The analysis of the Goldstone boson masses and decay
constants shows that the three-flavor condensate and some low-energy constants
are very sensitive to the value of the Zweig Rule violating constant L_6. A
similar study is performed in the case of the decay constants. A chiral sum
rule based on experimental data in the scalar channel is used to constrain L_6,
indicating a significant decrease between the two- and the three-flavor
condensates. The analysis of the scalar form factors of the pion at zero
momentum suggests that the pseudoscalar decay constant could also be suppressed
from N_f=2 to 3.

</DOC>
<DOC>
<DOCNO> 71442 </DOCNO>
Low-x scaling in $\gamma^*p$ total cross sections


  We show that the experimental data for the total virtual-photon proton cross
section, \sigma_{\gamma^*p} (W^2, Q^2), for x_{bj} \lsim 0.1 lie on a universal
curve, when plotted against \eta = (Q^2 + m^2_0)/ \Lambda^2(W^2), where
\Lambda^2 (W^2) = C_1 (W^2+W^2_0)^{C_2} is determined by the parameters m^2_0,
C_1, C_2 and W^2_0. The observed scaling law follows from the
generalized-vector-dominance/color-dipole picture of low-x deep inelastic
scattering.

</DOC>
<DOC>
<DOCNO> 84927 </DOCNO>
Radiative Falloff in Neutron Star Spacetimes


  We systematically study late-time tails of scalar waves propagating in
neutron star spacetimes. We consider uniform density neutron stars, for which
the background spacetime is analytic and the compaction of the star can be
varied continously between the Newtonian limit 2M/R << 1 and the relativistic
Buchdahl limit 2M/R = 8/9. We study the reflection of a finite wave packet off
neutron stars of different compactions 2M/R and find that a Newtonian, an
intermediate, and a highly relativistic regime can be clearly distinguished. In
the highly relativistic regime, the reflected signal is dominated by
quasi-periodic peaks, which originate from the wave packet bouncing back and
forth between the center of the star and the maximum of the background
curvature potential at R ~ 3 M. Between these peaks, the field decays according
to a power-law. In the Buchdahl limit 2M/R -> 8/9 the light travel time between
the center and the maximum or the curvature potential grows without bound, so
that the first peak arrives only at infinitely late time. The modes of neutron
stars can therefore no longer be excited in the ultra-relativistic limit, and
it is in this sense that the late-time radiative decay from neutron stars
looses all its features and gives rise to power-law tails reminiscent of
Schwarzschild black holes.

</DOC>
<DOC>
<DOCNO> 69969 </DOCNO>
Transversely polarized Lambda production


  Transversely polarized Lambda production in hard scattering processes is
discussed in terms of a leading twist T-odd fragmentation function which
describes the fragmentation of an unpolarized quark into a transversely
polarized Lambda. We focus on the properties of this function and its relevance
for the RHIC and HERMES experiments.

</DOC>
<DOC>
<DOCNO> 68848 </DOCNO>
QCD Working Group Report


  This is the report of the QCD working group at WHEPP 6. Discussions and work
on heavy ion collisions, polarised scattering, and collider phenomenology are
reported.

</DOC>
<DOC>
<DOCNO> 117995 </DOCNO>
Searching for cluster substructure using APM and ROSAT data


  We present a detailed study of the morphological features of 22 rich galaxy
clusters. Our sample is constructed from a cross-correlation of optical
(Abell+APM) data with X-ray (0.1 - 2.4) keV ROSAT pointed observations. We
systematically compare cluster images and morphological parameters in an
attempt to reliably identify possible substructure in both optical and the
X-ray images. To this end, we compute various moments of the optical and X-ray
surface-brightness distribution such as the ellipticities, center-of-mass
shifts and ellipsoidal orientations. We assess the significance of our results
using Monte Carlo simulations. We find significant correlations between the
optical and X-ray morphological parameters, indicating that in both parts of
the spectrum it is possible to identify correctly the dynamical state of a
cluster. Most of our clusters (17/22) have a good 1-to-1 correspondence between
the optical and the X-ray images and about 10 appear to have strong indications
of substructure. This corresponds to a minimum percentage of order 45 per cent
which is in very good accordance with other similar analyses. Finally, 5 out of
22 systems seem to have distinct subclumps in the optical which are not
verified in the X-ray images, and thus are suspect of being due to optical
projection effects. These results will serve as a useful guide in interpreting
subsequent analyses of large optical cluster catalogues.

</DOC>
<DOC>
<DOCNO> 11268 </DOCNO>
Why is the DNA Denaturation Transition First Order?


  We study a model for the denaturation transition of DNA in which the
molecules are considered as composed of a sequence of alternating bound
segments and denaturated loops. We take into account the excluded-volume
interactions between denaturated loops and the rest of the chain by exploiting
recent results on scaling properties of polymer networks of arbitrary topology.
The phase transition is found to be first order in d=2 dimensions and above, in
agreement with experiments and at variance with previous theoretical results,
in which only excluded-volume interactions within denaturated loops were taken
into account. Our results agree with recent numerical simulations.

</DOC>
<DOC>
<DOCNO> 118448 </DOCNO>
X-ray Spectra of a large sample of Quasars with ASCA


  The results from an X-ray spectral analysis of a large sample of quasars,
observed with ASCA, are presented. Data reduction leaves 62 quasars, 35
radio-loud and 27 radio-quiet, suitable for spectral analysis. Differences are
found between the radio-quiet quasars (RQQs) and the radio-loud quasars (RLQs),
in agreement with previous studies. A correlation between Gamma and optical
H-beta was also found for the radio-quiet quasars in this sample, whereby the
steepest X-ray spectra tend to be found in those objects with narrow H-beta
widths. The correlation is significant at >99% confidence, confirming the
well-known trend between Gamma and H-beta FWHM in Seyfert 1s (Brandt et al.
1997), but at higher luminosities. Other spectral complexities are observed
from this sample. A soft X-ray excess, with blackbody temperatures in the range
100 - 300 eV, is seen in many low z radio-quiet quasars. In most cases the
temperatures are probably too hot to originate directly from the disk. Iron K
line emission features are also found in the RQQs; but often from partially
ionised material. Indeed in the highest luminosity RQQs there is neither
evidence for iron line emission nor the reflection component expected from disk
models. These observations can be explained by an increase in the quasar
accretion rate with luminosity, leading to an increase in the ionisation state
of the surface layers of the disk. The occurrence of ionised or `warm'
absorbers is rare in this sample, with only 5 detections. However excess
neutral X-ray absorption is found towards several of the high z, predominantly
radio-loud, quasars. Although found to increase with quasar redshift, this
`intrinsic' absorption may be associated with radio-loud AGN.

</DOC>
<DOC>
<DOCNO> 69643 </DOCNO>
Comment on ``Comparison of strangeness production between A+A and p+p


  A recent paper on energy dependence of strangeness production in A+A and p+p
interactions written by Dunlop and Ogilvie (Phys. ReV. C61 031901(R) (2000)
indicates that there is a significant misunderstanding about the concept of
strangeness enhancement and its role as a signal of Quark Gluon Plasma
creation.
 In this comment we will try to clarify some essential points.

</DOC>
<DOC>
<DOCNO> 151737 </DOCNO>
The extremal limit of D-dimensional black holes


  The extreme limit of a class of D-dimensional black holes is revisited. In
the static limit, it is shown that well defined extremal limiting procedure
exists and it leads to new solutions of the type AdS2 times constant curvature
symmetric spaces.

</DOC>
<DOC>
<DOCNO> 7997 </DOCNO>
A planar extrapolation of the correlation problem that permits pairing


  It was observed previously that an SU(N) extension of the Hubbard model is
dominated, at large N, by planar diagrams in the sense of 't Hooft, but the
possibility of superconducting pairing got lost in this extrapolation. To allow
for this possibility, we replace SU(N) by U(N,q), the unitary group in a vector
space of quaternions. At the level of the free energy, the difference between
the SU(N)and U(N,q) extrapolations appears only to first nonleading order in N.

</DOC>
<DOC>
<DOCNO> 117122 </DOCNO>
Extracting molecular Hamiltonian structure from time-dependent


  We propose a formalism for extracting molecular Hamiltonian structure from
inversion of time-dependent fluorescence intensity data. The proposed method
requires a minimum of \emph{a priori} knowledge about the system and allows for
extracting a complete set of information about the Hamiltonian for a pair of
molecular electronic surfaces.

</DOC>
<DOC>
<DOCNO> 122482 </DOCNO>
The broad-band spectrum of 3C 120 observed by BeppoSAX


  We study a broad-band X-ray observation by BeppoSAX of the broad-line radio
galaxy 3C 120. The primary X-ray continuum is well described by a power law
with the photon index of Gamma=1.85+-0.05 and a high-energy break or a cutoff.
The obtained e-folding energy of about100-300 keV corresponds to kT of about 50
keV in thermal-Compton models. A soft X-ray excess is found at a statistical
significance of >98%$ Our physical best-fit model of the excess is
optically-thin emission from an extended plasma (with a luminosity of 2% of the
total X-ray luminosity), which interpretation is supported by an independent
finding of an extended soft X-ray halo in 3C 120. We find a moderate Compton
reflection component together with a moderately broad Fe K alpha line with an
equivalent width fully consistent with the strength of reflection, indicating
their origin in an optically-thick accretion disk extending relatively close to
the central black hole. We observe strong spectral variability during our 2-day
observation with Gamma varying from 1.7 to 2.0 and correlated with the soft
X-ray flux. The variability is very well modeled by thermal Comptonization in a
hot plasma irradiated by a variable UV flux. Both a hot patchy corona
outflowing with a mildly relativistic velocity away from a cold disk and a hot
inner accretion flow overlapping with the cold disk are viable geometries. The
presence of an outflow in the first case and an overlap between the hot and
cold phases in the second case are required by energy balance and the observed
strength of Compton reflection.

</DOC>
<DOC>
<DOCNO> 69815 </DOCNO>
Quark Mass Corrections to the Perturbative Thrust and its Effect on the


  We consider the effects of quark masses to the perturbative thrust in
$e^+e^-$ annihilation. In particular we show that perturbative power
corrections resulting from non-zero quark masses considerably alters the size
of the non-perturbative power corrections and consequently, significantly
changes the fitted value of $\alpha_s$.

</DOC>
<DOC>
<DOCNO> 118677 </DOCNO>
Physics of Grain Alignment


  Aligned grains provide one of the easiest ways to study magnetic fields in
diffuse gas and molecular clouds. How reliable our conclusions about the
inferred magnetic field depends critically on our understanding of the physics
of grain alignment. Although grain alignment is a problem of half a century
standing recent progress achieved in the field makes us believe that we are
approaching the solution of this mystery. I review basic physical processes
involved in grain alignment and show why mechanisms that were favored for
decades do not look so promising right now. I also discuss why the radiative
torque mechanism ignored for more than 20 years looks right now the most
powerful means of grain alignment.

</DOC>
<DOC>
<DOCNO> 10697 </DOCNO>
Universal gap fluctuations in the superconductor proximity effect


  Random-matrix theory is used to study the mesoscopic fluctuations of the
excitation gap in a metal grain or quantum dot induced by the proximity to a
superconductor. We propose that the probability distribution of the gap is a
universal function in rescaled units. Our analytical prediction for the gap
distribution agrees well with exact diagonalization of a model Hamiltonian.

</DOC>
<DOC>
<DOCNO> 85341 </DOCNO>
Gravitational Perturbations of a Radiating Spacetime


  This paper discusses the problem of gravitational perturbations of radiating
spacetimes. We lay out the theoretical framework for describing the interaction
of external gravitational fields with a radiating spacetime. This is done by
deriving the field perturbation equations for a radiating metric. The equations
are then specialized to a Vaidya spacetime. For the Hiscock ansatz of a linear
mass model of a radiating blackhole the equations are found separable. Further,
the resulting ordinary differential equations are found to admit analytic
solutions. We obtain the solutions and discuss their characteristics.

</DOC>
<DOC>
<DOCNO> 169856 </DOCNO>
Conditional teleportation using optical squeezers and photon counting


  We suggest a scheme of using two-mode squeezed vacuum for conditional
teleportation of quantum states of optical field. Alice mixes the input state
with one of the squeezed modes on another squeezing device and detects the
output photon numbers. The result is then communicated to Bob who shifts the
photon number of his part accordingly. This is a principally realizable
modification of the recent scheme [G.J. Milburn and S.L. Braunstein, Phys. Rev.
A 60, 937 (1999)] where measurements of photon number difference and phase sum
are considered. We show that for some classes of states this method can yield
very high fidelity of teleportation, nevertheless, the success probability may
be limited.

</DOC>
<DOC>
<DOCNO> 69110 </DOCNO>
Azimuthal asymmetry in transverse energy flow in nuclear collisions at


  The azimuthal pattern of transverse energy flow in nuclear collisions at RHIC
and LHC energies is considered. We show that the probability distribution of
the event-by-event azimuthal disbalance in transverse energy flow is
essentially sensitive to the presence of the semihard minijet component.

</DOC>
<DOC>
<DOCNO> 120066 </DOCNO>
Toward High-Precision Astrometry with WFPC2. I. Deriving an Accurate PSF


  The first step toward doing high-precision astrometry is the measurement of
individual stars in individual images, a step that is fraught with dangers when
the images are undersampled. The key to avoiding systematic positional error in
undersampled images is to determine an extremely accurate point-spread function
(PSF). We apply the concept of the {\it effective} PSF, and show that in images
that consist of pixels it is the ePSF, rather than the often-used instrumental
PSF, that embodies the information from which accurate star positions and
magnitudes can be derived. We show how, in a rich star field, one can use the
information from dithered exposures to derive an extremely accurate effective
PSF by iterating between the PSF itself and the star positions that we measure
with it. We also give a simple but effective procedure for representing spatial
variations of the HST PSF. With such attention to the PSF, we find that we are
able to measure the position of a single reasonably bright star in a single
image with a precision of 0.02 pixel (2 mas in WF frames, 1 mas in PC), but
with a systematic accuracy better than 0.002 pixel (0.2 mas in WF, 0.1 mas in
PC), so that multiple observations can reliably be combined to improve the
accuracy by $\surd N$.

</DOC>
<DOC>
<DOCNO> 120957 </DOCNO>
Does Pulsar B1757--24 Have a Fallback Disk?


  Radio pulsars are thought to spin-down primarily due to torque from magnetic
dipole radiation (MDR) emitted by the time-varying stellar magnetic field as
the star rotates. This assumption yields a `characteristic age' for a pulsar
which has generally been assumed to be comparable to the actual age. Recent
observational limits on the proper motion of pulsar B1757-24, however, revealed
that the actual age (>39 kyr) of this pulsar is much greater than its MDR
characteristic age (16 kyr) - calling into question the assumption of pure MDR
spin-down for this and other pulsars. To explore the possible cause of this
discrepancy, we consider a scenario in which the pulsar acquired an accretion
disk from supernova ejecta, and the subsequent spin-down occurred under the
combined action of MDR and accretion torques. A simplified model of the
accretion torque involving a constant mass inflow rate at the pulsar
magnetosphere can explain the age and period derivative of the pulsar for
reasonable values of the pulsar magnetic field and inflow rate. We discuss
testable predictions of this model.

</DOC>
<DOC>
<DOCNO> 169913 </DOCNO>
Decoherence in a single trapped ion due to engineered reservoir


  The decoherence in trapped ion induced by coupling the ion to the engineered
reservoir is studied in this paper. The engineered reservoir is simulated by
random variations in the trap frequency, and the trapped ion is treated as a
two-level system driven by a far off-resonant plane wave laser field. The
dependence of the decoherence rate on the amplitude of the superposition state
is given.

</DOC>
<DOC>
<DOCNO> 101057 </DOCNO>
Quantum invariants of links and new quantum field models


  We propose a gauge model of quantum electrodynamics (QED) and its nonabelian
generalization from which we derive knot invariants such as the Jones
polynomial. Our approach is inspired by the work of Witten who derived knot
invariants from quantum field theory based on the Chern-Simon Lagrangian. From
our approach we can derive new knot and link invariants which extend the Jones
polynomial and give a complete classification of knots and links. From these
new knot invariants we have that knots can be completely classified by the
power index $m$ of $TrR^{-m}$ where $R$ denotes the $R$-matrix for braiding and
is the monodromy of the Knizhnik-Zamolodchikov equation. A classification table
of knots can then be formed where prime knots are classified by prime integer
$m$ and nonprime knots are classified by nonprime integer $m$.

</DOC>
<DOC>
<DOCNO> 152168 </DOCNO>
Classical theory of canonical QCD on a space-like hypersurface


  The canonical formalism in classical theory of QCD is constructed on a
space-like hypersurface. The Poisson bracket on the space-like hypersurface is
defined and it plays an important role to describe every algebraic relation in
the canonical formalism into Lorentz covariant form. Surface integrals are
introduced as alternatives of field equations for quarks, gluons, and
Faddeev-Popov ghosts. It is shown that deformations of the space-like
hypersurface for surface integrals are generated by the interaction term of QCD
Hamiltonian density. By converting the Poisson bracket on the space-like
hypersurface to four-dimensional commutator, we can pass over to QCD in the
Heisenberg picture without spoiling the explicit Lorentz covariance.

</DOC>
<DOC>
<DOCNO> 10590 </DOCNO>
Geometric Formulation of Unique Quantum Stress Fields


  We present a derivation of the stress field for an interacting quantum system
within the framework of local density functional theory. The formulation is
geometric in nature and exploits the relationship between the strain tensor
field and Riemannian metric tensor field. The resultant expression obtained for
the stress field is gauge-invariant with respect to choice of energy density,
and therefore provides a unique, well-defined quantity. To illustrate this
formalism, we compute the pressure field for two phases of solid molecular
hydrogen.

</DOC>
<DOC>
<DOCNO> 178794 </DOCNO>
Antiflow of kaons in relativistic heavy ion collisions


  We compare relativistic transport model calculations to recent data on the
sideward flow of neutral strange K^0_s mesons for Au+Au collisions at 6 AGeV. A
soft nuclear equation of state is found to describe very well the positive
proton flow data measured in the same experiment. In the absence of kaon
potential, the K^0 flow pattern is similar to that of protons. The kaon flow
becomes negative if a repulsive kaon potential determined from the impulse
approximation is introduced. However, this potential underestimates the data
which exhibits larger antiflow. An excellent agreement with the data is
obtained when a relativistic scalar-vector kaon potential, that has stronger
density dependence, is used. We further find that the transverse momentum
dependence of directed and elliptic flow is quite sensitive to the kaon
potential in dense matter.

</DOC>
<DOC>
<DOCNO> 12178 </DOCNO>
Basins of attraction on random topography


  We investigate the consequences of fluid flowing on a continuous surface upon
the geometric and statistical distribution of the flow. We find that the
ability of a surface to collect water by its mere geometrical shape is
proportional to the curvature of the contour line divided by the local slope.
Consequently, rivers tend to lie in locations of high curvature and flat
slopes. Gaussian surfaces are introduced as a model of random topography. For
Gaussian surfaces the relation between convergence and slope is obtained
analytically. The convergence of flow lines correlates positively with drainage
area, so that lower slopes are associated with larger basins. As a consequence,
we explain the observed relation between the local slope of a landscape and the
area of the drainage basin geometrically. To some extent, the slope-area
relation comes about not because of fluvial erosion of the landscape, but
because of the way rivers choose their path. Our results are supported by
numerically generated surfaces as well as by real landscapes.

</DOC>
<DOC>
<DOCNO> 12830 </DOCNO>
Glassy Spin Freezing and NMR Wipeout Effect in the High-T_c


  We report on 139La and 63Ccu NMR/NQR measurements in the high-Tc
superconductor La1.90Sr0.10CuO4 with Tc=26.5 K. Spin fluctuations probed by
139La spin-lattice relaxation (T1), continuously slow down on cooling through
Tc. We argue that spin-freezing and superconductivity are bulk effects in this
sample. Thus, both phenomena have to coexist microscopically. The distribution
of 139La T1 values at low temperature reveals a wide spread of spin fluctuation
frequencies in CuO2 planes. A simple estimate shows that Cu nuclei at sites
where electronic fluctuations are the slowest are not observable because of too
short relaxation times (wipeout effect). This means that the Cu NQR wipeout,
observed in this sample, can be explained primarily by slow magnetic, rather
than charge, fluctuations. This result does not rule out the connection between
wipeout effect and charge stripe order [Hunt et al., Phys. Rev. Lett. 82, 4300
(1999)], but it indicates that the relationship between both phenomena is not
straightforward. We argue that the wipeout fraction cannot define a proper
order parameter for a stripe phase, and cannot be used alone as a criterion for
its existence.

</DOC>
<DOC>
<DOCNO> 121490 </DOCNO>
The ISM of Low Surface Brightness Galaxies


  Using Monte Carlo radiative transfer techniques, we model the dust content of
the edge-on low surface brightness (LSB) galaxy UGC 7321 and explore the
effects of dust on its disk color gradients. Dust alone cannot explain the
large radial disk color gradients observed in this galaxy and we find that a
significant fraction (~50%) of the dust in UGC 7321 appears to be contained in
a clumped medium, indicating that at least some LSB galaxies can support a
modest multi-phase ISM structure. In addition, we report some of the first
direct detections of molecular gas (CO) in LSB galaxies.

</DOC>
<DOC>
<DOCNO> 40506 </DOCNO>
Observation of the conversion decay $\phi\to\pi^0e^+e^-$ at CMD-2


  Using 15.1^{-1} of data collected by CMD-2 in the $\phi$-meson energy range,
the branching ratio of the conversion decay $\phi\to\pi^0e^+e^-$ has been
measured for the first time: B(\phi\to\pi^0e^+e^-) = (1.22 \pm 0.34 \pm 0.21)
\cdot 10 ^{-5}.

</DOC>
<DOC>
<DOCNO> 102398 </DOCNO>
Operads in Higher-Dimensional Category Theory


  The purpose of this dissertation is to set up a theory of generalized operads
and multicategories, and to use it as a language in which to propose a
definition of weak n-category. Included is a full explanation of why the
proposed definition of n-category is a reasonable one, and of what happens when
n=2. Generalized operads and multicategories play other parts in
higher-dimensional algebra too, some of which are outlined here: for instance,
they can be used to simplify the opetopic approach to n-categories expounded by
Baez, Dolan and others, and are a natural language in which to discuss
enrichment of categorical structures.

</DOC>
<DOC>
<DOCNO> 67967 </DOCNO>
Locally Anisotropic Kinetic Processes and Thermodynamics in Curved


  The kinetic theory is formulated with respect to anholonomic frames of
reference on curved spacetimes. By using the concept of nonlinear connection we
develop an approach to modelling locally anisotropic kinetic processes and, in
corresponding limits, the relativistic non-equilibrium thermodynamics with
local anisotropy. This lead to a unified formulation of the kinetic equations
on (pseudo) Riemannian spaces and in various higher dimensional models of
Kaluza-Klein type and/or generalized Lagrange and Finsler spaces. The
transition rate considered for the locally anisotropic transport equations is
related to the differential cross section and spacetime parameters of
anisotropy. The equations of states for pressure and energy in locally
anisotropic thermodynamics are derived. The obtained general expressions for
heat conductivity, shear and volume viscosity coefficients are applied to
determine the transport coefficients of cosmic fluids in spacetimes with
generic local anisotropy. We emphasize that such locally anisotropic structures
are induced also in general relativity if we are modelling physical processes
with respect to frames with mixed sets of holonomic and anholonomic basis
vectors which naturally admits an associated nonlinear connection structure.

</DOC>
<DOC>
<DOCNO> 117077 </DOCNO>
Mirror modes: Nonmaxwellian distributions


  We perform direct analysis of mirror mode instabilities from the general
dielectric tensor for several model distributions, in the longwavelength limit.
The growth rate at the instability threshold depends on the derivative of the
distribution for zero parallel energy. The maximum growth rate is always $\sim
k_\parallel v_{T\parallel}$ and the instability is of nonresonant kind. The
instability growth rate and its dependence on the propagation angle depend on
the shape of the ion and electron distribution functions.

</DOC>
<DOC>
<DOCNO> 10209 </DOCNO>
Elementary Theory of Line Broadening and Four-wave Mixing in


  The basic results of optical line broadening and four-wave mixing are deduced
from first principles based on time-dependent many-body purturbation theory.
The formalism allows us to write all the results in terms of nonequilibrium
distribution functions without the need to assume a quasiequilibrium
temperature. The connection of these results to the quantum Boltzmann equation
is shown, which is also derived from first principles. Last, specific
predictions for electron-electron scattering are reviewed.

</DOC>
<DOC>
<DOCNO> 72076 </DOCNO>
Phenomenological study of the interactions violating the R-parity


  The supersymmetric extension of the Standard Model can contain interactions
violating the so-called R-parity symmetry. Such couplings would lead to the
lepton and/or baryon number violation and modify deeply the phenomenology of
supersymmetry at future particle colliders. We have worked out tests of the
R-parity violating interactions. First, we have studied clear signals of the
single production of supersymmetric partners of the Standard Model particles,
which involves the R-parity violating interactions, in the context of physics
at next leptonic and hadronic colliders. The results show that strong
sensitivities could be obtained on the soft supersymmetry breaking parameters
and indicate the possibility of an improvement of one to two order of magnitude
concerning the present indirect limits on the values of several R-parity
violating coupling constants. Besides, it has been verified that the single
superpartner production analysis offers the opportunity to reconstruct in a
model independent way some superpartner masses with an high accuracy. Secondly,
we have studied CP symmetry violation effects, due to the complex phases of
R-parity violating coupling constants, in the pair production of either
fermions or sfermions of different flavors at future leptonic colliders. We
have seen notably that the single top quark production allows to test the CP
violation in the hadronic sector. The main conclusion of these works is that
complex phases of certain R-parity violating coupling constants could be
observed, and in particular within a scenario where those couplings would
exhibit a strong hierarchy in flavor space.

</DOC>
<DOC>
<DOCNO> 102181 </DOCNO>
A functional-analytic theory of vertex (operator) algebras, II


  For a finitely-generated vertex operator algebra of central charge c, a
locally convex topological completion is constructed. We construct on the
completion a structure of an algebra over the operad of the c/2-th power of the
determinant line bundle over the moduli space of genus-zero Riemann surfaces
with ordered analytically parametrized boundary components. In particular, the
completion is a module for the semi-group of the c/2-th power of the
determinant line bundle over the moduli space of conformal equivalence classes
of annuli with analytically parametrized boundary components. The results in
Part I for Z-graded vertex algebras are also reformulated in terms of the
framed little disk operad. Using May's recognition principle for double loop
spaces, one immediate consequence of such operadic formulations is that the
compactly generated spaces corresponding to (or the k-ifications of) the
locally convex completions constructed in Part I and in the present paper have
the weak homotopy types of double loop spaces. We also generalize the results
above to locally-grading-restricted conformal vertex algebras and to modules.

</DOC>
<DOC>
<DOCNO> 70449 </DOCNO>
Universality of non-leading logarithmic contributions in


  We consider the resummation of the logarithmic contributions to the region of
small transverse momenta in the distributions of high-mass systems (lepton
pairs, vector bosons, Higgs particles, ....) produced in hadron collisions. We
point out that the resummation formulae that are usually used to compute the
distributions in perturbative QCD involve process-dependent form factors and
coefficient functions. We present a new universal form of the resummed
distribution, in which the dependence on the process is embodied in a single
perturbative factor. The new form simplifies the calculation of non-leading
logarithms at higher perturbative orders. It can also be useful to
systematically implement process-independent non-perturbative effects in
transverse-momentum distributions. We also comment on the dependence of these
distributions on the factorization and renormalization scales.

</DOC>
<DOC>
<DOCNO> 84547 </DOCNO>
Numerical Relativity and Inhomogeneous Cosmologies


  In this work numerical methods for solving Einstein's equations are developed
and applied to the study of inhomogeneous cosmological models.
  A two-dimensional computer code is described which implements two advanced
numerical methods: LeVeque's multi-dimensional high-resolution integration
scheme which allows accurate evolution of solutions containing discontinuities
or steep gradients, and an adaptive mesh refinement (AMR) algorithm which
enables the local resolution of a simulation to vary dynamically in response to
the behaviour of the evolved solution.
  A family of hyperbolic formulations of the Einstein equations is derived by
generalization of an evolution system proposed by Frittelli and Reula, and
numerical solutions produced using these formulations are compared to solutions
produced using alternative reductions of the evolutions equations. Properties
of the harmonic time slicing condition are also investigated, and analytic and
numerical results concerning the formation of coordinate singularities are
presented.
  Numerical simulations are performed of planar cosmologies, described using
Gowdy's reduction of the Einstein equations, and U(1)-symmetric cosmologies,
described using Moncrief's reduction of the Einstein equations, with the
spacetimes in both cases being vacuum. Numerical studies follow up on the work
of Berger, Moncrief and co-workers, with attention being focused on the
small-scale features that develop in the models and the behaviour of linear and
nonlinear gravitational waves.

</DOC>
<DOC>
<DOCNO> 11566 </DOCNO>
Large two-level magnetoresistance effect in doped manganite grain


  We performed a systematic analysis of the tunneling magnetoresistance (TMR)
effect in single grain boundary junctions formed in epitaxial
La(2/3)Ca(1/3)MnO(3) films deposited on SrTiO(3) bicrystals. For magnetic
fields H applied parallel to the grain boundary barrier, an ideal two-level
resistance switching behavior with sharp transitions is observed with a TMR
effect of up to 300% at 4.2 K and still above 100% at 77 K. Varying the angle
between H and the grain boundary results in differently shaped resistance vs H
curves. The observed behavior is explained within a model of magnetic domain
pinning at the grain boundary interface.

</DOC>
<DOC>
<DOCNO> 84254 </DOCNO>
A Theory of Quantum Gravity from First Principles


  When quantum fields are studied on manifolds with boundary, the corresponding
one-loop quantum theory for bosonic gauge fields with linear covariant gauges
needs the assignment of suitable boundary conditions for elliptic differential
operators of Laplace type. There are however deep reasons to modify such a
scheme and allow for pseudo-differential boundary-value problems. When the
boundary operator is allowed to be pseudo-differential while remaining a
projector, the conditions on its kernel leading to strong ellipticity of the
boundary-value problem are studied in detail. This makes it possible to develop
a theory of one-loop quantum gravity from first principles only, i.e. the
physical principle of invariance under infinitesimal diffeomorphisms and the
mathematical requirement of a strongly elliptic theory.

</DOC>
<DOC>
<DOCNO> 9103 </DOCNO>
Interface charged impurity scattering in semiconductor MOSFETs and


  We present the results on the anomalous 2D transport behavior by employing
Drude-Boltzmann transport theory and taking into account the realistic charge
impurity scattering effects. Our results show quantitative agreement with the
existing experimental data in several different systems and address the origin
of the strong and non-monotonic temperature dependent resistivity.

</DOC>
<DOC>
<DOCNO> 99833 </DOCNO>
Fourier Tauberian Theorems and Applications


  The main aim of the paper is to present a general version of the Fourier
Tauberian theorem for monotone functions. This result, together with Berezin's
inequality, allows us to obtain a refined version the Li-Yau estimate for the
counting function of the Dirichlet Laplacian which implies the Li-Yau estimate
itself and, at the same time, the asymptotic results obtained by the
variational method.

</DOC>
<DOC>
<DOCNO> 84926 </DOCNO>
Non-time-orthogonality, Gravitational Orbits, and Thomas Precession


  Non-time-orthogonal analysis of rotating frames is applied to objects in
gravitational orbits and found to be internally consistent. The object's
surface speed about its axis of rotation, but not its orbital speed, is shown
to be readily detectable by any "enclosed box" experimenter on the surface of
such an object. Sagnac type effects manifest readily, but by somewhat subtle
means. The analysis is extended to objects bound in non-gravitational orbit,
where it is found to be fully in accord with the traditional analysis of Thomas
precession.

</DOC>
<DOC>
<DOCNO> 117645 </DOCNO>
Numerical Simulations of Globular Cluster Formation


  We examine various physical processes associated with the formation of
globular clusters by using the three-dimensional Smoothed Particle
Hydrodynamics (SPH) code. Our code includes radiative cooling of gases, star
formation, energy feedback from stars including stellar winds and supernovae,
and chemical enrichment by stars. We assume that, in the collapsing galaxy,
isothermal cold clouds form through thermal condensations and become
proto-globular clouds. We calculate the size of proto-globular clouds by
solving the linearized equations for perturbation. We compute the evolution of
the inner region of the proto-cloud with our SPH code for various initial
radius and initial composition of gases. When the initial gases contain no
heavy elements, the evolution of proto-clouds sensitively depends on the
initial radius. For a smaller initial radius, the initial star burst is so
intense that the subsequent star formation occurs in the central regions to
form a dense star cluster as massive as the globular cluster. When the initial
gases contain some heavy elements, the metallicity of gases affects the
evolution and the final stellar mass. If the initial radius of the
proto-globular clouds was relatively large, the formation of a star cluster as
massive as the globular clusters requires the initial metallicity as high as
[Fe/H] $\geq -2$. The self-enrichment of heavy elements in the star cluster
does not occur in all cases.

</DOC>
<DOC>
<DOCNO> 170525 </DOCNO>
Multi-Player and Multi-Choice Quantum Game


  In this paper, we investigate a multi-player and multi-choice quantum game.
We start from two-player and two-choice game and the result is better than its
classical version. Then we extend it to N-player and N-choice cases. In the
quantum domain, we provide a strategy with which players can always avoid the
worst outcome. Also, by changing the value of the parameter of the initial
state, the probabilities for players to get the best payoff will be much higher
that in its classical version.

</DOC>
<DOC>
<DOCNO> 8411 </DOCNO>
Nucleation theory and the phase diagram of the magnetization-reversal


  The phase diagram of the dynamic magnetization-reversal transition in pure
Ising systems under a pulsed field competing with the existing order can be
explained satisfactorily using the classical nucleation theory. Indications of
single-domain and multi-domain nucleation and of the corresponding changes in
the nucleation rates are clearly observed. The nature of the second time scale
of relaxation, apart from the field driven nucleation time, and the origin of
its unusual large values at the phase boundary are explained from the
disappearing tendency of kinks on the domain wall surfaces after the withdrawal
of the pulse. The possibility of scaling behaviour in the multi-domain regime
is identified and compared with the earlier observations.

</DOC>
<DOC>
<DOCNO> 150609 </DOCNO>
Pinned Branes and New Non Lorentz Invariant Theories


  We describe a mechanism for localising branes in ambient space. When a 3-form
flux is turned on in a Taub-NUT space, an M5-brane gets an effective potential
that pins it to the center of the space. A similar effect occurs for M2-branes
and D-branes with appropriate fluxes. In carefully chosen limits of the
external parameters, this leads to new theories that are decoupled from gravity
and appear to break Lorentz invariance. For example, we predict the existence
of a new 5+1D theory that breaks Lorentz invariance at high-energy and has a
low-energy description of N tensor multiplets with (1,0) supersymmetry. We also
predict a new type of theory that, similarly to the little-string theory
decouples from gravity by a dynamical (rather than kinematical) argument.

</DOC>
<DOC>
<DOCNO> 169713 </DOCNO>
Conditions for manipulation of a set of entangled pure states


  We derive a sufficient condition for a set of pure states, each entangled in
two remote $N$-dimensional systems, to be transformable to
$k$-dimensional-subspace equivalent entangled states ($k\leq N$) by same local
operations and classical communication. If $k=N$, the condition is also
necessary. This condition reveals the function of the relative marginal density
operators of the entangled states in the entanglement manipulation without
sufficient information of the initial states.

</DOC>
<DOC>
<DOCNO> 120162 </DOCNO>
X-ray absorption and rapid variability of the dwarf Seyfert nucleus of


  We report the detection of an absorbed central X-ray source and its strong,
rapid variability in NGC4395, the least luminous Seyfert nucleus known. The
X-ray source exhibits a number of flares with factors of 3-4 flux changes
during a half day ASCA observation. Such X-ray variability is in constrast to
the behaviour of other low luminosity active galaxies. It provides further
support for an accreting black hole model rather than an extreme stellar
process in accounting for the nuclear activity of NGC4395. The soft X-ray
emission below 3 keV is strongly attenuated by absorption. The energy spectrum
in this absorption band shows a dramatic change in response to the variation in
continuum luminosity. A variable warm absorber appears to be an explanation for
the spectral change. The absorption-corrected 2-10 keV luminosity is 4e39 erg/s
for a source distance of 2.6 Mpc, and at 1 keV is one order of magnitude above
previous ROSAT estimates. Our X-ray results infer the nuclear source of NGC4395
to be a scaled-down version of higher luminosity Seyfert nuclei, with an
intermediate mass (10^4-10^5 Msun) black hole, unlike the nearby low luminosity
active galaxies in which underfed massive black holes are suspected to reside.

</DOC>
<DOC>
<DOCNO> 100650 </DOCNO>
Higher Type Adjunction Inequalities in Seiberg-Witten Theory


  In this paper, we derive new adjunction inequalities for embedded surfaces
with non-negative self-intersection number in four-manifolds. These formulas
are proved by using relations between Seiberg-Witten invariants which are
induced from embedded surfaces. To prove these relations, we develop the
relevant parts of a Floer theory for four-manifolds which bound circle-bundles
over Riemann surfaces.

</DOC>
<DOC>
<DOCNO> 123160 </DOCNO>
Super-Eddington Atmospheres that Don't Blow Away


  We show that magnetized, radiation dominated atmospheres can support steady
state patterns of density inhomogeneity that enable them to radiate at far
above the Eddington limit, without suffering mass loss. The inhomogeneities
consist of periodic shock fronts bounding narrow, high-density regions,
interspersed with much broader regions of low density. The radiation flux
avoids the regions of high density, which are therefore weighed down by
gravity, while gas in the low-density regions is slammed upward into the shock
fronts by radiation force. As the wave pattern moves through the atmosphere,
each parcel of matter alternately experiences upward and downward forces, which
balance on average. Magnetic tension shares the competing forces between
regions of different densities, preventing the atmosphere from blowing apart.
We calculate the density structure and phase speed of the wave pattern, and
relate these to the wavelength, the density contrast, and the factor by which
the net radiation flux exceeds the Eddington limit. In principle, this factor
can be as large as the ratio of magnetic pressure to mean gas pressure, or the
ratio of radiation pressure to gas pressure, whichever is smaller. Although the
magnetic pressure must be large compared to the mean gas pressure in order to
support a large density contrast, it need not be large compared to the
radiation pressure. These highly inhomogeneous flows could represent the
nonlinear development of the "photon bubble" instability discovered by Gammie.
We briefly discuss the applicability of these solutions to astrophysical
systems.

</DOC>
<DOC>
<DOCNO> 118676 </DOCNO>
The Balmer Wavelength Range of BP Tauri


  We have analyzed all the observations of BP Tauri taken by the International
Ultraviolet Explorer in the low resolution (6 A), long wavelength (from 1850 to
 3350 A) range. This dataset contains 61 spectra. These spectra do not show any
correlation between the continuum flux and the MgII line flux, thus resolving a
standing controversy in the literature concerning the origin of the MgII line
flux. There is no correlation between the color temperature of the UV continuum
and the average value of its flux. Using models of the accretion process
developed by Calvet & Gullbring (1998), we obtain energy fluxes, accretion spot
sizes, and accretion rates from the IUE observations of BP Tauri. We find
average energy fluxes of 5.0 10^11 ergs cm^{-2} s^{-1}, average spot sizes of
4.4 10^{-3} times the stellar surface, and average accretion rates of 1.6 10^-8
msun/yr. Our analysis shows that the particle energy flux and the UV flux in
the stellar surface are proportional to each other. Most strikingly, we observe
a correlation between accretion rate and spot size, with the spot size
increasing as the square of the accretion rate. Based on the results of a
simulation, we conclude that geometrical effects are not enough to account for
this effect. Current models of the accretion process fail to reproduce such an
effect, suggesting the need of using more realistic descriptions of the stellar
field when treating magnetospheric accretion. There may also be an unmodelled
efficiency factor that determines how matter is loaded into the field lines.

</DOC>
<DOC>
<DOCNO> 69696 </DOCNO>
Logarithmic Potential Model of Quigg and Rosner as a Generalization of


  Exploiting the explicit mass formulae for logarithmic potential model of
Quigg and Rosner it is shown that at least on the level of mass-relations this
model reproduces the naive quark model relations and generalizes the last one
in case of highly non-trivial potential. Generalization includes the relations
for higher values of orbital quantum numbers. In particular, preditions for
recently discovered atom-like P-states are no worse than for any other
potential models.The advantage consists in simplicity of approach.

</DOC>
<DOC>
<DOCNO> 68505 </DOCNO>
The structure function of semi-inclusive heavy flavour decays in field


  We consider the decay of a heavy flavour into an inclusive hadronic state X
of invariant mass m_X small with respect to its energy E_X, m_X << E_X. The
electron spectrum and the hadronic mass distribution in semileptonic b -> u
decays, or the photon spectrum in b -> s gamma decays, all require, close to
their endpoints, a control over this region. This region is affected both by
non-perturbative phenomena related to the Fermi motion of the heavy quark and
by perturbative soft gluon radiation in the final state (Sudakov form
factor).Fermi motion can be described by the shape function f (m*), which
represents the distribution of the effective mass m* of the heavy quark at
disintegration time. We perform a factorization with a simple technique in
order to consistently separate perturbative from non-perturbative effects. We
find that the shape function, contrary to naive expectations,is not a physical
distribution, as it is affected by substantial regularization scheme effects,
controlling even the leading, double-logarithmic term. It factorizes, however,
the bulk of non-perturbative effects in lattice-like regularizations. Some
non-perturbative effects are present in the coefficient function even at
leading twist, but they are expected to be suppressed on physical grounds.
Finally, we clarify a controversial factor of 2 in the evolution kernel of the
shape function.

</DOC>
<DOC>
<DOCNO> 12785 </DOCNO>
Dynamics of ferromagnetic spherical spin models with power law


  We solve the Langevin dynamics of d-dimensional ferromagnetic spherical
models with interactions that decay with distance as r^-(d+sigma). The long
time dynamics of correlations and responses are studied in the different
dynamical regimes and the validity of fluctuation-dissipation relations (or its
violation) are shown. In particular, we show that the fluctuation-dissipation
ratio X(t+t_w,t_w) is assymptotically a function only of the waiting time t_w
in the aging regime and that X -> 0 as t_w -> oo . The results are valid in any
finite dimension d and for 0 < sigma < 2, where short range behaviour is
recovered. We also solve the T=0 Cahn-Hilliard dynamics of this model
(conserved order parameter). An analysis of the multiscaling behaviour of the
autocorrelation function is presented.

</DOC>
<DOC>
<DOCNO> 101740 </DOCNO>
Twisted Higgs bundles and the fundamental group of compact K\"ahler


  We study polystable Higgs bundles twisted by a line bundle over a compact
K\"ahler manifold. These form a Tannakian category when the first and second
Chern classes of the bundle are zero. In this paper we identify the
corresponding Tannaka group in the case in which the line bundle is of finite
order. This group is described in terms of the pro-reductive completion of the
fundamental group of the manifold, and the character associated to the line
bundle.

</DOC>
<DOC>
<DOCNO> 70999 </DOCNO>
The QCD potential at O(1/m^2): Complete spin-dependent and


  Within an effective field theory framework, we obtain an expression, with
O(1/m^2) accuracy, for the energies of the gluonic excitations between heavy
quarks, which holds beyond perturbation theory. For the singlet heavy
quark--antiquark energy, in particular, we also obtain an expression in terms
of Wilson loops. This provides, twenty years after the seminal work of Eichten
and Feinberg, the first complete expression for the heavy quarkonium potential
up to O(1/m^2) for pure gluodynamics. Several errors present in the previous
literature (also in the work of Eichten and Feinberg) have been corrected. We
also briefly discuss the power counting of NRQCD in the non-perturbative
regime.

</DOC>
<DOC>
<DOCNO> 11378 </DOCNO>
Kondo effect in mesoscopic systems


  The Kondo effect may develop in those cases where there are non-commuting
operators describing the interaction between the conduction electrons and
impurities or defects with internal degrees of freedom. This interaction may
involve spin or orbital variables. There are cases where the conduction
electrons have conserved quantum numbers that do not appear in the coupling. An
example is where the Kondo effect involves orbital degrees of freedom, and the
interaction is independent of the real spins of the electrons, which are
conserved and lead to the two-channel Kondo (2CK) problem. The low temperature
behavior is very different for the one- and two-channel cases, as in the first
case a Fermi liquid is formed while in the second one strong deviations appear
and a non-Fermi liquid state is realized. Mesoscopic samples provide a unique
possibility to study a few or even a single Kondo impurities. In this paper we
first review how the original spin Kondo problem is affected by surface
anisotropy and the fluctuations of the density of states in point contacts
(PCs). We discuss the physics of a single magnetic impurity on the surface of a
sample. The orbital 2CK effect due to dynamical defects is considered. The
nature of these defects is not known but they are excellent candidates to
describe the zero-bias anomalies with non-Fermi liquid character in PCs, and
the dephasing time and transport in short wires. There are two main concerns
regarding this interpretation: First, the tunneling centers formed by heavy
impurities may produce a Kondo temperature that is too low, and secondly, the
splittings seen in the experiments are much smaller than expected from this
model. It would be therefore extremely important to identify the microstructure
of these two-level systems and find new realizations for them.

</DOC>
<DOC>
<DOCNO> 39847 </DOCNO>
Threshold expansion of Feynman diagrams within a configuration space


  The near threshold expansion of generalized sunset-type (water melon)
diagrams with arbitrary masses is constructed by using a configuration space
technique. We present analytical expressions for the expansion of the spectral
density near threshold and compare it with the exact expression obtained
earlier using the method of the Hankel transform. We formulate a generalized
threshold expansion with partial resummation of the small mass corrections for
the strongly asymmetric case where one particle in the intermediate state is
much lighter than the others.

</DOC>
<DOC>
<DOCNO> 116432 </DOCNO>
Very long storage times and evaporative cooling of cesium atoms in a


  We have trapped cesium atoms over many minutes in the focus of a CO$_2$-laser
beam employing an extremely simple laser system. Collisional properties of the
unpolarized atoms in their electronic ground state are investigated. Inelastic
binary collisions changing the hyperfine state lead to trap loss which is
quantitatively analyzed. Elastic collisions result in evaporative cooling of
the trapped gas from 25 $\mu$K to 10 $\mu$K over a time scale of about 150 s.

</DOC>
<DOC>
<DOCNO> 122710 </DOCNO>
Galaxy Morphological Segregation in Clusters: Local vs. Global


  We study the relative fraction of galaxy morphological types in clusters, as
a function of the projected local galaxy density and different global
parameters: cluster projected gas density, cluster projected total mass density
, and reduced clustercentric distance. Since local and global densities are
correlated, we have considered different tests to search for the parameters to
which segregation show the strongest dependence. Also, we have explored the
results of our analysis applied to the central regions of the clusters and
their outskirts. We consider a sample of clusters of galaxies with temperature
estimates to derive the projected mass density profile and the 500 density
contrast radius ($r_{500}$) using the NFW model and the scaling relation
respectively. The X-ray surface brightness profiles are used to obtain the
projected gas density assuming the hydrostatic equilibrium model. Our results
suggest that the morphological segregation in clusters is controlled by the
local galaxy density in the outskirts. On the other hand, the global projected
mass density, shows the strongest correlation with the fraction of
morphological types in the central high density region, with a marginal
dependence on the local galaxy density.

</DOC>
<DOC>
<DOCNO> 152314 </DOCNO>
Non-commutative Geometry and the Higgs Masses


  We study a non-commutative generalization of the standard electroweak model
proposed by Balakrishna, Gursey and Wali [ Phys.Lett. B254(1991)430] that is
formulated in terms of the derivations Der_2(M_3) of a three-dimensional
representation of the su(2) Lie algebra of weak isospin. The linearized Higgs
field equations and the scalar boson mass eigenvalues are explicitly given. A
light Higgs boson with mass around 130 GeV together with four very heavy scalar
bosons are predicted.

</DOC>
<DOC>
<DOCNO> 116468 </DOCNO>
The Fractal Universe


  In this talk, we touch upon the chaotic and fractal aspects of the Universe.

</DOC>
<DOC>
<DOCNO> 178475 </DOCNO>
Radiative Corrections to Elastic Electron-Proton Scattering for


  We analyze the radiative correction to high energy elastic electron-proton
scattering of polarized electrons. We show that if the approximations inherent
in the calculations developed by Tsai and given in the work of Mo and Tsai,
which have been used in the analysis of almost all experimental data pertaining
to medium and high energy elastic electron scattering for the past three
decades, are maintained, then the same radiative correction applies both in the
case of initially polarized and unpolarized electrons.

</DOC>
<DOC>
<DOCNO> 116677 </DOCNO>
Synchronisation, binding and the role of correlated firing in fast


  Does synchronization between action potentials from different neurons in the
visual system play a substantial role in solving the binding problem? The
binding problem can be studied quantitatively in the broader framework of the
information contained in neural spike trains about some external correlate,
which in this case is object configurations in the visual field. We approach
this problem by using a mathematical formalism that quantifies the impact of
correlated firing in short time scales. Using a power series expansion, the
mutual information an ensemble of neurons conveys about external stimuli is
broken down into firing rate and correlation components. This leads to a new
quantification procedure directly applicable to simultaneous multiple neuron
recordings. It theoretically constrains the neural code, showing that
correlations contribute less significantly than firing rates to rapid
information processing. By using this approach to study the limits upon the
amount of information that an ideal observer is able to extract from a
synchrony code, it may be possible to determine whether the available amount of
information is sufficient to support computational processes such as feature
binding.

</DOC>
<DOC>
<DOCNO> 170313 </DOCNO>
New Lower Bound on Fermion Binding Energies


  We derive a new lower bound for the ground state energy $E^{\rm F}(N,S)$ of N
fermions with total spin S in terms of binding energies $E^{\rm F}(N-1,S \pm
1/2)$ of (N-1) fermions. Numerical examples are provided for some simple
short-range or confining potentials.

</DOC>
<DOC>
<DOCNO> 69681 </DOCNO>
New Constraints on "Cool" Dark Matter


  It has been suggested that a sterile neutrino \nu_s which mixes with standard
neutrinos can form nonthermal ``cool'' Dark Matter if its mass and mixing angle
fall in the ranges 0.1 keV \lsim m_s \lsim 10 keV and 10^{-10} \lsim \sin^2
\theta \lsim 10^{-4}, respectively. We point out that the required mixing makes
these heavy neutrinos unstable. The dominant decay mode is into three light
neutrinos, but the most stringent constraint comes from the non-observation of
radiative decays into a single light neutrino and a photon. Moreover, we point
out that the density of thermal relics of such \nu_{s}'s would be too high,
unless the reheating temperature after inflation was below \sim 10 GeV.

</DOC>
<DOC>
<DOCNO> 120930 </DOCNO>
Blue horizontal branch stars in metal-rich globular clusters. II. 47 Tuc


  Atmospheric parameters (effective temperature, surface gravity) and radial
velocities are derived for 12 candidate blue horizontal branch (HB) stars in
the globular clusters 47 Tuc and NGC 362, which so far have been known to
contain primarily red HB stars. The spectroscopic targets were selected from
the catalog of hot stars detected in these clusters at 1600 A using the
Ultraviolet Imaging Telescope (UIT). Spectroscopic analyses of these stars
reveal, however, that one of the four HB candidate targets in 47 Tuc, and five
out of the eight targets in NGC 362 are probably background stars belonging to
the Small Magellanic Cloud. With the exception of the photometric binary
MJ38529 in 47 Tuc, the parameters of those stars that are probable members of
47 Tuc and NGC 362 agree well with canonical HB evolution. The three hot stars
in 47 Tuc all have 10,000 K < Teff < 15,000 K and include one photometric
binary, which suggests that they might have a different physical origin than
the dominant red HB population. The somewhat cooler blue HB stars in NGC 362
show more continuity with the dominant red HB population and might simply arise
from red giants with unusually high mass loss.

</DOC>
<DOC>
<DOCNO> 84820 </DOCNO>
Wave packets and initial conditions in quantum cosmology


  We discuss the construction of wave packets resulting from the solutions of a
class of Wheeler-DeWitt equations in Robertson-Walker type cosmologies. We
present an ansatz for the initial conditions which leads to a unique
determination of the expansion coefficients in the construction of the wave
packets with probability distributions which, in an interesting contrast to
some of the earlier works, agree well with all possible classical paths. The
possible relationship between these initial conditions and signature transition
in the context of classical cosmology is also discussed.

</DOC>
<DOC>
<DOCNO> 100002 </DOCNO>
On the classification of q-algebras


  The problem is the classification of the ideals of ``free differential
algebras", or the associated quotient algebras, the q-algebras; being finitely
generated, unital C-algebras with homogeneous relations and a q-differential
structure. This family of algebras includes the quantum groups, or at least
those that are based on simple (super) Lie or Kac-Moody algebras. Their
classification would encompass the so far incompleted classification of
quantized (super) Kac-Moody algebras and of the (super) Kac-Moody algebras
themselves. These can be defined as singular limits of q-algebras, and it is
evident that to deal with the q-algebras in their full generality is more
rational than the examination of each singular limit separately. This is not
just because quantization unifies algebras and superalgebras, but also because
the points "q = 1" and "q = -1" are the most singular points in parameter
space. In this paper one of two major hurdles in this classification program
has been overcome. Fix a set of integers n_1,...,n_k, and consider the space
B_Q of homogeneous polynomials of degree n_1 in the generator e_1, and so on.
Assume that there are no constants among the polynomials of lower degree, in
any one of the generators; in this case all constants in the space B_Q have
been classified. The task that remains, the more formidable one, is to remove
the stipulation that there are no constants of lower degree.

</DOC>
<DOC>
<DOCNO> 71662 </DOCNO>
Radiative Corrections to Chargino Production in Electron-Positron


  The results of a complete one-loop calculation for the production of chargino
pairs in electron-positron collisions, including the option of polarized beams,
are presented. The calculation has been performed in the on-shell
renormalization scheme. Applications to the integrated cross section, to the
forward-backward asymmetry for unpolarized beams, and to the left-right
asymmetry show that the higher-order effects have a sizeable influence on the
theoretical predictions and therefore should be properly taken into account for
detailed studies in the MSSM.

</DOC>
<DOC>
<DOCNO> 118991 </DOCNO>
Perturbations of self-gravitating, ellipsoidal superfluid-normal fluid


  We study the perturbation modes of rotating superfluid ellipsoidal figures of
equilibrium in the framework of the two-fluid superfluid hydrodynamics and
Newtonian gravity. Our calculations focus on linear perturbations of background
equilibria in which the two fluids move together, the total density is uniform,
and the densities of the two components are proportional to one another, with
ratios that are independent of position. The motions of the two fluids are
coupled by mutual friction, as formulated by Khalatnikov. We show that there
are two general classes of modes for small perturbations: one class in which
the two fluids move together and the other in which there is relative motion
between them. The former are identical to the modes found for a single fluid,
except that the rate of viscous dissipation, when computed in the secular (or
``low Reynolds number'') approximation under the assumption of a constant
kinematic viscosity, is diminished by a factor $f_N$, the fraction of the total
mass in the normal fluid. The relative modes are completely new, and are
studied in detail for a range of values for the phenomenological mutual
friction coefficients, relative densities of the superfluid and normal
components, and, for Roche ellipsoids, binary mass ratios. We find that there
are no new secular instabilities connected with the relative motions of the two
fluid components. Moreover, although the new modes are subject to viscous
dissipation (a consequence of viscosity of the normal matter), they do not emit
gravitational radiation at all.

</DOC>
<DOC>
<DOCNO> 8401 </DOCNO>
Finite-time singularity in the dynamics of the world population,


  Contrary to common belief, both the Earth's human population and its economic
output have grown faster than exponential, i.e., in a super-Malthusian mode,
for most of the known history. These growth rates are compatible with a
spontaneous singularity occuring at the same critical time 2052 +- 10 signaling
an abrupt transition to a new regime. The degree of abruptness can be infered
from the fact that the maximum of the world population growth rate was reached
in 1970, i.e., about 80 years before the predicted singular time, corresponding
to approximately 4% of the studied time interval over which the acceleration is
documented. This rounding-off of the finite-time singularity is probably due to
a combination of well-known finite-size effects and friction and suggests that
we have already entered the transition region to a new regime. In theoretical
support, a multivariate analysis coupling population, capital, R&D and
technology shows that a dramatic acceleration in the population during most of
the timespan can occur even though the isolated dynamics do not exhibit it.
Possible scenarios for the cross-over and the new regime are discussed.
Nottale, Chaline and Grou have recently independently applied a log-periodic
analysis to the main crises of different civilisations. It is striking that
these two independent analyses based on a different data set gives a critical
time which is compatible within the error bars.

</DOC>
<DOC>
<DOCNO> 13709 </DOCNO>
No indications of metal-insulator transition for systems of interacting


  The influence of Coulomb interaction on transport properties of spinless
electrons in small disordered two dimensional systems is studied within a tight
binding model. Spatial correlations, inverse participation ratio, and
multifractal spectrum of the zero temperature local tunneling amplitude as well
as the DC Kubo conductance are traced as function of the interaction strength
$U$. When $U$ is increased, all of the above quantities are shifted rather
smoothly towards localized behavior, indicating the absence of an interaction
driven insulator-metal transition.

</DOC>
<DOC>
<DOCNO> 101246 </DOCNO>
Locally Minimal Projections


  Given an n-tuple {a_1, ..., a_n} of self-adjoint operators on an infinite
dimensional Hilbert space H and a positive integer k, there exists a projection
p of rank k such that, for each for j = 1, ..., n, pa_jp is a scalar multiple
of p. Assuming that {a_1, ...,a_n, 1} is a linearly independent set in the
Calkin algebra, then p can be chosen of infinite rank.

</DOC>
<DOC>
<DOCNO> 84552 </DOCNO>
Generalized Laws of Black Hole Thermodynamics and Quantum Conservation


  Four classical laws of black hole thermodynamics are extended from exterior
(event) horizon to interior (Cauchy) horizon. Especially, the first law of
classical thermodynamics for Kerr-Newman black hole (KNBH) is generalized to
those in quantum form. Then five quantum conservation laws on the KNBH
evaporation effect are derived in virtue of thermodynamical equilibrium
conditions. As a by-product, Bekenstein-Hawking's relation $ S=A/4 $ is exactly
recovered.

</DOC>
<DOC>
<DOCNO> 70173 </DOCNO>
Inverted Hierarchy Models of Neutrino Masses


  We study models of neutrino masses which naturally give rise to an inverted
mass hierarchy and bi-maximal mixing. The models are based on the see-saw
mechanism with three right-handed neutrinos, which generates a single mass term
of the form $\nu_e(\nu_{\mu}+\nu_{\tau})$ corresponding to two degenerate
neutrinos $\nu_e$ and $\nu_{\mu}+\nu_{\tau}$, and one massless neutrino
$\nu_{\mu}-\nu_{\tau}$. Atmospheric neutrino oscillations are accounted for if
the degenerate mass term is about $5\times 10^{-2}$ eV. Solar neutrino
oscillations of the Large Mixing Angle MSW type arise when small perturbations
are included leading to a mass splitting between the degenerate pair of about
$(1.7-2.0)\times 10^{-4}$ eV for the successful cases. We study the conditions
that such models must satisfy in the framework of a U(1) family symmetry broken
by vector singlets, and catalogue the simplest examples. We then perform a
renormalisation group analysis of the neutrino masses and mixing angles,
assuming the supersymmetric standard model, and find modest radiative
corrections of a few per cent, showing that the model is stable. At low
energies we find $\sin^22\theta_{23}\approx 0.93-0.96$ and
$\sin^22\theta_{12}\approx 0.9-1.0$.

</DOC>
<DOC>
<DOCNO> 150923 </DOCNO>
Path Integral Methods and Applications


  These lectures are intended as an introduction to the technique of path
integrals and their applications in physics. The audience is mainly first-year
graduate students, and it is assumed that the reader has a good foundation in
quantum mechanics. No prior exposure to path integrals is assumed, however.
  The path integral is a formulation of quantum mechanics equivalent to the
standard formulations, offering a new way of looking at the subject which is,
arguably, more intuitive than the usual approaches. Applications of path
integrals are as vast as those of quantum mechanics itself, including the
quantum mechanics of a single particle, statistical mechanics, condensed matter
physics and quantum field theory.
  After an introduction including a very brief historical overview of the
subject, we derive a path integral expression for the propagator in quantum
mechanics, including the free particle and harmonic oscillator as examples. We
then discuss a variety of applications, including path integrals in
multiply-connected spaces, Euclidean path integrals and statistical mechanics,
perturbation theory in quantum mechanics and in quantum field theory, and
instantons via path integrals.
  For the most part, the emphasis is on explicit calculations in the familiar
setting of quantum mechanics, with some discussion (often brief and schematic)
of how these ideas can be applied to more complicated situations such as field
theory.

</DOC>
<DOC>
<DOCNO> 71705 </DOCNO>
Supersymmetric Hybrid Inflation


  The non-supersymmetric and supersymmetric versions of hybrid inflation are
summarized. It is emphasized that supersymmetric hybrid inflation (with its
extensions) is an extremely "natural" inflationary scenario since it does not
require "tiny" parameters, its superpotential has the most general form allowed
by the symmetries, and it can be protected against radiative or supergravity
corrections. A concrete supersymmetric grand unified theory which leads to
hybrid inflation, solves the mu problem and generates seesaw masses for the
light neutrinos is constructed. The "reheating" which follows hybrid inflation
is studied in this theory. It is shown that the gravitino constraint on the
"reheat" temperature can be "naturally" satisfied. Also, the observed baryon
asymmetry of the universe can be generated via a primordial leptogenesis
consistently with the requirements from solar and atmospheric neutrino
oscillations. Extensions of the standard supersymmetric hybrid inflationary
scenario which are still consistent with all these requirements but can also
avoid the cosmological disaster from the possible copious monopole production
at the abrupt termination of standard hybrid inflation are constructed. They
rely on utilizing the leading non-renormalizable correction to the standard
hybrid inflationary superpotential and are necessary for higher unified gauge
groups which predict the existence of monopoles.

</DOC>
<DOC>
<DOCNO> 150740 </DOCNO>
Dynamical Symmetry Breaking and Static Limits of Extended


  From a supersymmetry covariant source extension of N=2 SYM we study
non-trivial thermodynamical limits thereof. Using an argument by one of us
about the solution of the strong CP problem and the uniqueness of the QCD
ground state we find that the dependence of the effective potential on the
defining field operators is severely restricted. In contrast to the solution by
Seiberg and Witten an acceptable infrared behavior only exists for broken
supersymmetry while the gauge symmetry remains unbroken.

</DOC>
<DOC>
<DOCNO> 121369 </DOCNO>
Morphological and kinematic signatures of a binary central star in the


  We present narrow-band optical images, VLA-A 3.6 cm continuum and H92alpha
emission line data and high resolution long-slit [N II] spectra of Hu 2-1. The
formation of Hu 2-1 appears dominated by anisotropic mass ejection during the
late AGB stage of its progenitor and by variable, ``precessing'' collimated
bipolar outflows during the proto-PN and/or early PN phases. The data strongly
support the existence of a binary central star at center of Hu 2-1: (1) the
brightness distribution of the bipolar lobes and inner shell is
point-symmetric, and the bipolar lobes show departures from axial symmetry; (2)
the position of the central star is off-center; (3) mass ejection towards the
equatorial plane is detected; (4) ``precessing'' collimated outflows are
present. Besides all this circumstantial evidences, the analysis of the
kinematics shows that the systemic velocity of the bipolar outflows does not
coincide with the systemic velocity of the nebula. We propose that this
velocity difference is a direct evidence of orbital motion of the ejection
source in a binary system. Assuming a reasonable range of masses for the
progenitor stars, the orbital velocity of ~10 km/s corresponds to a semi-major
axis of 9-27 AU and to a period of 25-80 yr. The formation of Hu 2-1 is
analyzed within current scenarios of PN formation with binary central stars.

</DOC>
<DOC>
<DOCNO> 178528 </DOCNO>
Dynamical model for Pion - Nucleon Bremsstrahlung


  A dynamical model based on effective Lagrangians is proposed to describe the
bremsstrahlung reaction $ \pi N \to \pi N \gamma$ at low energies. The
$\Delta(1232)$ degrees of freedom are incorporated in a way consistent with
both, electromagnetic gauge invariance and invariance under contact
transformations. The model also includes the initial and final state
rescattering of hadrons via a T-matrix with off-shell effects. The $\pi N
\gamma$ differential cross sections are calculated using three different
T-matrix models and the results are compared with the soft photon
approximation, and with experimental data. The aim of this analysis is to test
the off-shell behavior of the different T-matrices under consideration.

</DOC>
<DOC>
<DOCNO> 102541 </DOCNO>
Generalised Pattern Avoidance


  Recently, Babson and Steingrimsson have introduced generalised permutation
patterns that allow the requirement that two adjacent letters in a pattern must
be adjacent in the permutation. We consider pattern avoidance for such
patterns, and give a complete solution for the number of permutations avoiding
any single pattern of length three with exactly one adjacent pair of letters.
We also give some results for the number of permutations avoiding two different
patterns. Relations are exhibited to several well studied combinatorial
structures, such as set partitions, Dyck paths, Motzkin paths, and involutions.
Furthermore, a new class of set partitions, called monotone partitions, is
defined and shown to be in one-to-one correspondence with non-overlapping
partitions.

</DOC>
<DOC>
<DOCNO> 152327 </DOCNO>
Landau-Ginzburg Description of D-branes on ALE Spaces


  We study the Landau-Ginzburg (LG) mirror theory of the non-linear sigma model
on the ALE space ${\cal M}$ obtained by resolving the singularity of the
orbifold ${\bf C}^2/{\bf Z}_N$. In the LG description, the data of the BPS
spectrum and the lines of marginal stability are encoded in the special
Lagrangian submanifolds of the mirror manifold $\hat{{\cal M}}$. Our LG
description is quite simple as compared with the quiver gauge theory analysis
near the orbifold point. Furthermore our mirror analysis can be applied to any
point on the moduli space of ${\cal M}$.

</DOC>
<DOC>
<DOCNO> 68582 </DOCNO>
Hermitian quark mass matrices with four texture zeros


  We provide a complete and systematic analysis of hermitian, hierarchical
quark mass matrices with four texture zeros. Using triangular mass matrices,
each pattern of texture zeros is readily shown to lead to a definite relation
between the CKM parameters and the quark masses. Nineteen pairs are found to be
consistent with present data, and one other is marginally acceptable. In
particular, no parallel structure between the up and down mass matrices is
found to be favorable with data.

</DOC>
<DOC>
<DOCNO> 71853 </DOCNO>
Cosmic Birefringence within the Framework of Heterotic String Theory


  Low energy string theory predicts the existence of an axion field which can
lead to cosmic birefringence. We solve the electromagnetic wave equations in
the presence of such an axion and a dilaton field in order to determine their
effect on the polarization of light. We find that the presence of dilaton field
leads to a nontrivial modification of the final result. We comment on the
possibility of discovering such an effect by observations of radio wave
polarizations from distant radio galaxies and quasars. We have also determined
the limits on the string theory parameters that are imposed by the current
polarization data from distant quasars and radio galaxies.

</DOC>
<DOC>
<DOCNO> 123255 </DOCNO>
Ultra-High Energy Cosmic Rays and Symmetries of Spacetime


  High energy cosmic rays allow probing phenomena that are inacessible to
accelerators. Observation of cosmic rays, presumebly protons, with energies
beyond $4 \times 10^{19} eV$, the so-called Greisen-Zatsepin-Kuzmin (GZK)
cut-off, give origin to two puzzles: How do particles accelerate to such
energies ? Are their sources within $50 - 100 Mpc$ from Earth, or Lorentz
invariance is actually a broken symmetry ?

</DOC>
<DOC>
<DOCNO> 10662 </DOCNO>
Phase Transitions Driven by Vortices in 2D Superfluids and


  The Landau-Ginzburg-Wilson hamiltonian is studied for different values of the
parameter $\lambda$ which multiplies the quartic term (it turns out that this
is equivalent to consider different values of the coherence length $\xi$ in
units of the lattice spacing $a$). It is observed that amplitude fluctuations
can change dramatically the nature of the phase transition: for small values of
$\lambda$ ($\xi/a > 0.7$), instead of the smooth Kosterlitz-Thouless transition
there is a {\em first order} transition with a discontinuous jump in the vortex
density $v$ and a larger non-universal drop in the helicity modulus. In
particular, for $\lambda$ sufficiently small ($\xi/a \cong 1$), the density of
bound pairs of vortex-antivortex below $T_c$ is so low that, $v$ drops to zero
almost for all temperature $T<Tc$.

</DOC>
<DOC>
<DOCNO> 170427 </DOCNO>
From quantum nonlocality to mind-brain interaction


  Orthodox Copenhagen quantum theory renounces the quest to understand the
reality in which we are imbedded, and settles for practical rules that describe
connections between our observations. However, an examination of certain
nonlocal features of quantum theory suggests that the perceived need for this
renunciation was due to the uncritical importation from classical physics of a
crippling metaphysical prejudice, and that rejection of that prejudice opens
the way to a dynamical theory of the interaction between mind and brain that
has significant explanatory power.

</DOC>
<DOC>
<DOCNO> 122459 </DOCNO>
General relativistic spectra of accretion disks around rotating neutron


  General relativistic spectra from accretion disks around rotating neutron
stars in the appropriate space-time geometry for several different equation of
state, spin rates and mass of the compact object have been computed. The
analysis involves the computation of the relativistically corrected radial
temperature profiles and the effect of Doppler and gravitational red-shifts on
the spectra. Light bending effects have been omitted for simplicity. The
relativistic spectrum is compared with the Newtonian one and it is shown that
the difference between the two is primarily due to the different radial
temperature profile for the relativistic and Newtonian disk solutions.
  To facilitate direct comparison with observations, a simple empirical
function has been presented which describes the numerically computed
relativistic spectra well. This empirical function (which has three parameters
including normalization) also describes the Newtonian spectrum adequately. Thus
the function can in principle be used to distinguish between the two. In
particular, the best fit value of one of the parameters ($\beta$-parameter)
$\approx 0.4$ for the Newtonian case, while it ranges from 0.1 to 0.35 for
relativistic case depending upon the inclination angle, EOS, spin rate and mass
of the neutron star. Constraining this parameter by fits to future
observational data of X-ray binaries will indicate the effect of strong gravity
in the observed spectrum.

</DOC>
<DOC>
<DOCNO> 99754 </DOCNO>
Addendum to Theorem 10.4 in "Boundaries of Analytic Varieties"


  The main result of [HL] (Annals of Math. 102 (1975), 223--290) gives a
characterization of the boundaries of complex subvarieties in C^n. An
application of this result concerning pseudoconvexity, namely Theorem 10.4 in
[HL], is amplified.

</DOC>
<DOC>
<DOCNO> 68128 </DOCNO>
Parton picture of inclusive quasi-elastic electron scattering off nuclei


  A parton picture of inclusive quasi-elastic electron-nucleus scattering,
where individual nucleons are treated as (non point-like) partons of the
nucleus, is presented. All the necessary target-mass corrections to asymptotic
scaling are evaluated and a new scaling variable is obtained. Recent inclusive
data from Jefferson Lab are analyzed and shown to scale in terms of the new
variable. The new approach allows to extract in a model-independent way the
nucleon light-cone momentum distribution in the nucleus.

</DOC>
<DOC>
<DOCNO> 117166 </DOCNO>
Comment on the Electron Self-Energy Calculation


  A quantum-electrodynamical description of the self-energy in which the
interaction is propagated with the velocity of light instead of instantaneously
gives rise to a modification of the photon propagator identical with the
convergence factor. We discuss a physical meaning of the convergence procedure
used in the electron self-energy calculation.

</DOC>
<DOC>
<DOCNO> 80886 </DOCNO>
Spectra of massive QCD Dirac Operators from Random Matrix Theory: all


  The microscopic spectral eigenvalue correlations of QCD Dirac operators in
the presence of dynamical fermions are calculated within the framework of
Random Matrix Theory (RMT). Our approach treats the low--energy correlation
functions of all three chiral symmetry breaking patterns (labeled by the Dyson
index $\beta=1,2$ and 4) on the same footing, offering a unifying description
of massive QCD Dirac spectra. RMT universality is explicitly proven for all
three symmetry classes and the results are compared to the available lattice
data for $\beta=4$.

</DOC>
<DOC>
<DOCNO> 84790 </DOCNO>
Let's call it Nonlocal Quantum Physics


  In the following we undertake to derive quantum theory as a stochastic
low-energy and coarse-grained theory from a more primordial discrete and
basically geometric theory living on the Planck scale and which (as we argue)
possibly underlies also \tit{string theory}. We isolate the so-called
\tit{ideal elements} which represent at the same time the cornerstones of the
framework of ordinary quantum theory and show how and why they encode the
\tit{non-local} aspects, being ubiquituous in the quantum realm, in a, on the
surface, local way. We show that the quantum non-locality emerges in our
approach as a natural consequence of the underlying \tit{two-storey} nature of
space-time or the physical vacuum, that is, quantum theory turns out to be a
residual effect of the geometric depth structure of space-time on the Planck
scale. We indicate how the \tit{measurement problem} and the emergence of the
\tit{macroscopic sub-regime} can be understood in this framework.

</DOC>
<DOC>
<DOCNO> 178422 </DOCNO>
Angular momentum projected analysis of Quadrupole Collectivity in


  A microscopic angular momentum projection after variation is used to describe
quadrupole collectivity in (^{30,32,34}Mg) and (^{32,34,36,38}Si). The
Hartree-Fock-Bogoliubov states obtained in the quadrupole constrained mean
field approach are taken as intrinsic states for the projection. Excitation
energies of the first (2^{+}) states and the (B(E2,0^{+}\to 2^{+})) transition
probabilities are given. A reasonable agreement with available experimental
data is obtained. It is also shown that the mean field picture of those nuclei
is strongly modified by the projection.

</DOC>
<DOC>
<DOCNO> 121051 </DOCNO>
First UVES observations of beryllium in very metal-poor stars


  We report on a attempt to detect beryllium in two dwarf stars of the Galactic
halo with metallicities below one thousandth solar. The data were obtained
during the Commissioning of the Ultraviolet and Visible Echelle Spectrograph
(UVES) mounted on the ESO VLT Kueyen telescope, and show the potential of UVES
for studies in the UV-optical domain. We claim a beryllium detection in LP
815--43 ([Fe/H]~-2.95,[Be/H]=-13.09) at the 99.7% confidence level, while only
an upper limit can be set for the second target CD -24 17504 ([Fe/H]~-3.30,
[Be/H]~-13.39). These results suggest that the trend of beryllium with
metallicity keeps decreasing as lower metallicities are probed, with no
evidence for flattening. In CD -24 17504 we also analyzed the Li I line at
6708A, and derived a lithium abundance close to the Spite plateau.

</DOC>
<DOC>
<DOCNO> 120696 </DOCNO>
The Effect of Dust on Photometric Redshift Measurement; A


  A new method is developed for estimating photometric redshifts to galaxies,
using realistic template SEDs, extending over four decades in wavelength (i.e.
from 0.05 micron to 1 mm). The template SEDs are constructed for four different
spectral types of galaxies (elliptical, spiral, irregular and starburst),
satisfying the following characteristics: a). they are normalised to produce
the observed colours of galaxies at z ~ 0; b). incorporate the
chemo-photometric spectral evolution of galaxies of different types, in
agreement with the observations; c). allow treatment of dust contribution and
its evolution with redshift, consistent with the spectral evolution model; d).
include absorption and re-emission of radiation by dust and hence, realistic
estimates of the far-infrared radiation; e). include correction for
inter-galactic absorption by Lyman continuum and Lyman forest. Using these
template SEDs, the photometric redshifts are estimated to an accuracy of ~
0.11. The effect on the estimated photometric redshifts, due to assumptions in
the evolutionary population synthesis models, are investigated and discussed.
  The simultaneous and self-consistent modelling of both the photometric and
chemical evolution of galaxies and the effect of dust, makes this technique
particularly useful for high redshift galaxies. Moreover, since the template
SEDs (at different redshifts) cover the range from UV to far-infrared and
sub-mm wavelengths, one could consistently use the optimised SEDs to estimate
the contribution from individual galaxies to these wavelengths, where no
observational data are available.

</DOC>
<DOC>
<DOCNO> 83400 </DOCNO>
Hot-pressing process modeling for medium density fiberboard (MDF)


  In this paper we present a numerical solution for the mathematical modeling
of the hot-pressing process applied to medium density fiberboard. The model is
based in the work of Humphrey[82], Humphrey and Bolton[89] and Carvalho and
Costa[98], with some modifications and extensions in order to take into account
mainly the convective effects on the phase change term and also a conservative
numerical treatment of the resulting system of partial differential equations.

</DOC>
<DOC>
<DOCNO> 152236 </DOCNO>
Multi-centered black holes in gauged D=5 supergravity


  One of the important consequences of the no-force condition for BPS states is
the existence of stable static multi-center solutions, at least in ungauged
supergravities. This observation has been at the heart of many developments in
brane physics, including the construction of intersecting branes and reduced
symmetry D-brane configurations corresponding to the Coulomb branch of the
gauge theory. However the search for multi-center solutions to gauged
supergravities has proven rather elusive. Because of the background curvature,
it appears such solutions cannot be static. Nevertheless even allowing for time
dependence, general multi-center solutions to gauged supergravity have yet to
be constructed. In this letter we investigate the construction of such
solutions for the case of D=5, N=2 gauged supergravity coupled to an arbitrary
number of vector multiplets. Formally, we find a family of time dependent
multi-center black hole solutions which are easily generalized to the case of
AdS supergravities in general dimensions. While these are not true solutions,
as they have a complex metric and gauge potential, they may be related to a
Wick rotated theory or to a theory where the coupling is taken to be imaginary.
These solutions thus provide a partial realization of true multi-center
black-holes in gauged supergravities.

</DOC>
<DOC>
<DOCNO> 120009 </DOCNO>
Consequences of Interstellar Absorption for Models of Anomalous X-ray


  We examine properties of thermal radiation emitted by strongly magnetized
neutron stars (NSs). In particular, we show that the pulsation amplitudes of
the energy-integrated flux are an increasing function of the absorption column
density to the source. This is especially important for the interpretation of
the Anomalous $X$-ray Pulsars (AXPs) as cooling neutron stars with high
magnetic fields. We show that the high-pulsation amplitudes observed in these
objects are consistent with cooling models, if the large amount of absorption
to these sources is taken into account. We also show that cooling models imply
inferred radii of the emitting regions on the order of $\sim 5-6$ times smaller
than the actual NS radii, again in agreement with observations.

</DOC>
<DOC>
<DOCNO> 100342 </DOCNO>
Covariant q-Differential Calculus and its Deformations at q^N=1


  We construct the generalized version of covariant Z_3-graded differential
calculus introduced by one of us (R.K.), and then extended to the case of
arbitrary Z_N grading. Here our main purpose is to establish the recurrence
formulae for the N-th power of covariant q-differential D_q = d_q + A and to
analyze more closely the particular case of q being an Nth primitive root of
unity. The generalized notions of connection and curvature are introduced and
several examples of realization are displayed for N=3 and N=4. Finally we
briefly discuss the idea of infinitesimal deformations of the parameter q in
the complex plane.

</DOC>
<DOC>
<DOCNO> 69539 </DOCNO>
NLO Exclusive Evolution Kernels


  We outline a formalism used for a construction of two-loop flavor singlet
exclusive evolution kernels in the MS bar scheme. The approach is based on the
known pattern of conformal symmetry breaking in MS bar as well as constraints
arising from the superconformal algebra of the N = 1 super Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 80775 </DOCNO>
Approximate Ginsparg-Wilson fermions: A first test


  We construct a 4-d lattice Dirac operator D using a systematical expansion in
terms of simple operators on the lattice. The Ginsparg-Wilson equation turns
into a system of coupled equations for the expansion coefficients of D. We
solve these equations for a finite parametrization of D and find an approximate
solution of the Ginsparg-Wilson equation. We analyze the spectral properties of
our D for various ensembles of quenched SU(3) configurations. Improving the
gauge field action considerably improves the spectral properties of our D.

</DOC>
<DOC>
<DOCNO> 84775 </DOCNO>
Intrinsic Geometry of a Null Hypersurface


  We apply Cartan's method of equivalence to construct invariants of a given
null hypersurface in a Lorentzian space-time. This enables us to fully classify
the internal geometry of such surfaces and hence solve the local equivalence
problem for null hypersurface structures in 4-dimensional Lorentzian
space-times.

</DOC>
<DOC>
<DOCNO> 70854 </DOCNO>
On the mystery of the cosmic vacuum energy density


  After a short history of the $\Lambda$-term it is explained why the
(effective) cosmological constant is expected to obtain contributions from
short-distance physics, corresponding to an energy at least as large as the
Fermi scale. The actual tiny value of the cosmological constant by particle
physics standards represents, therefore, one of the deepest mysteries of
present-day fundamental physics. Recent proposals of an approach to the
cosmological constant problem which make use of (large) extra dimensions are
briefly discussed. Cosmological models with a dynamical $\Lambda$, which
attempt to avoid the disturbing cosmic coincidence problem, are also reviewed.

</DOC>
<DOC>
<DOCNO> 117922 </DOCNO>
Relativistic flows in blazars


  The radiation we observe from blazars is most likely the product of the
transformation of bulk kinetic energy into random energy. This process must
have a relatively small efficiency (e.g. 10%) if jets are to power the extended
radio-structures. Recent results suggest that the average power reaching the
extended radio regions and lobes is of the same order of that produced by
accretion and illuminating the emission line clouds. Most of the radiative
power is produced in a well localized region of the jet, and, at least during
flares, is mainly emitted in the gamma-ray band. A possible scenario
qualitatively accounting for these facts is the internal shock model, in which
the central engine produces a relativistic plasma flow in an intermittent way.

</DOC>
<DOC>
<DOCNO> 9206 </DOCNO>
Heterogeneous condensation in dense media


  The theoretical description of the heterogeneous nucleation kinetics is
presented. This description takes into account the perturbation of the vapor
phase initiated by the growing droplets. The form of the density profile around
the growing droplet is analyzed which leads to some special approximations.
Then the process of nucleation in the whole system is described. As the result
all main characteristics of the process are determined analytically.

</DOC>
<DOC>
<DOCNO> 71661 </DOCNO>
Loop Induced Flavor Changing Neutral Decays of the Top Quark in a


  Decays of the top quark induced by flavor changing neutral currents (FCNC)
are known to be extremely rare events within the Standard Model. This is so not
only for the decay modes into gauge bosons, but most notably in the case of the
Higgs channels, e.g. t-> H_{SM}+c, with a branching fraction of 10^{-13} at
most. Therefore, detection of FCNC top quark decays in a future high-energy,
and high-luminosity, machine like the LHC or the LC would be an indisputable
signal of new physics. In this paper we show that within the simplest extension
of the SM, namely the general two-Higgs-doublet model, the FCNC top quark
decays into Higgs bosons, t->(h^{0},H^{0},A^{0})+c, can be the most favored
FCNC modes -- comparable or even more efficient than the gluon channel t-> g+c.
In both cases the optimal results are obtained for Type II models. However,
only the Higgs channels can have rates reaching the detectable level (10^{-5}),
with a maximum of order 10^{-4} which is compatible with the charged Higgs
bounds from radiative B-meson decays. We compare with the previous results
obtained in the Higgs sector of the MSSM.

</DOC>
<DOC>
<DOCNO> 71302 </DOCNO>
Sum Rules in the CFL Phase of QCD at finite density


  We study the asymmetry between the vector current and axial-vector current
correlators in the colour-flavour locking (CFL) phase of QCD at finite density.
Using Weinberg's sum rules, we compute the decay constant $f_\pi$ of the
Goldstone modes and find agreement with previous derivations. Using Das's sum
rule, we also estimate the contribution of electromagnetic interactions to the
mass of the charged modes. Finally, we comment on low temperature corrections
to the effective field theory describing the Goldstone bosons.

</DOC>
<DOC>
<DOCNO> 101207 </DOCNO>
A birational invariant for algebraic group actions


  We construct a birational invariant for certain algebraic group actions. We
use this invariant to classify linear representations of finite abelian groups
up to birational equivalence, thus answering, in a special case, a question of
E. B. Vinberg and giving a family of counterexamples to a related conjecture of
P. I. Katsylo. We also give a new proof of a theorem of M. Lorenz on birational
equivalence of quantum tori (in a slightly expanded form) by applying our
invariant in the setting of PGL_n-varieties.

</DOC>
<DOC>
<DOCNO> 117910 </DOCNO>
Subaru Observations for the K-band Luminosity Distribution of Galaxies


  We investigate the $K$-band luminosity distribution of galaxies in the region
of clusters at $z\sim1.2$ near to the radio galaxy 3C 324. The imaging data
were obtained during the commissioning period of the Subaru telescope. There is
a significant excess of the surface number density of the galaxies with $K =$
17--20 mag in the region within $\sim$ 40'' from 3C 324. At this bright end,
the measured luminosity distribution shows a drop, which can be represented by
the exponential cut off of the Schechter-function formula; the best-fitted
value of the characteristic magnitude, $K^{*}$, is $\sim 18.4\pm0.8$. This
measurement follows the evolutionary trend of the $K^*$ of the rich clusters
observed at an intermediate redshift, which is consistent with passive
evolution models with a formation redshift $z_f \gtsim 2$. At $K \gtsim 20$
mag, however, the excess of the galaxy surface density in the region of the
clusters decreases abruptly, which may imply that the luminosity function of
the cluster galaxies has a negative slope at the faint end. This may imply
strong luminosity segregation between the inner and outer parts of the
clusters, or some deficit of faint galaxies in the cluster central region of
the cluster.

</DOC>
<DOC>
<DOCNO> 85311 </DOCNO>
Casimir Effect of Graviton and the Entropy Bound


  In this note we calculate the Casimir effect of free thermal gravitons in
Einstein universe and discuss how it changes the entropy bound condition
proposed recently by Verlinde [hep-th/0008140] as a higher dimensional
generalization of Cardy's formula for conformal field theories (CFT). We find
that the graviton's Casimir effect is necessary in order not to violate
Verlinde's bound for weakly coupled CFT. We also comment on the implication of
this new Cardy's formula to the thermodynamics of black $p$-brane.

</DOC>
<DOC>
<DOCNO> 101547 </DOCNO>
Strongly typical representations of the basic classical Lie


  The category of representations with a strongly typical central character of
a basic classical Lie superalgebra is proven to be equivalent to the category
of representations of its even part corresponding to an appropriate central
character.
   For a Lie superalgebra $osp(1,2l)$ the category of representations with a
"generic" weakly atypical central character is described.

</DOC>
<DOC>
<DOCNO> 118990 </DOCNO>
Discovery of Two High-Magnetic-Field Radio Pulsars


  We report the discovery of two young isolated radio pulsars with very high
inferred magnetic fields. PSR J1119-6127 has period P = 0.407 s, and the
largest period derivative known among radio pulsars, Pdot = 4.0e-12. Under
standard assumptions these parameters imply a characteristic spin-down age of
only tau = 1.6 kyr and a surface dipole magnetic field strength of B = 4.1e13
G. We have measured a stationary period-second-derivative for this pulsar,
resulting in a braking index of n = 2.91+-0.05. We have also observed a glitch
in the rotation of the pulsar, with fractional period change Delta_P/P =
-4.4e-9. Archival radio imaging data suggest the presence of a previously
uncataloged supernova remnant centered on the pulsar. The second pulsar, PSR
J1814-1744, has P = 3.975 s and Pdot = 7.4e-13. These parameters imply tau = 85
kyr, and B = 5.5e13 G, the largest of any known radio pulsar.
  Both PSR J1119-6127 and PSR J1814-1744 show apparently normal radio emission
in a regime of magnetic field strength where some models predict that no
emission should occur. Also, PSR J1814-1744 has spin parameters similar to the
anomalous X-ray pulsar (AXP) 1E 2259+586, but shows no discernible X-ray
emission. If AXPs are isolated, high magnetic field neutron stars
(``magnetars''), these results suggest that their unusual attributes are
unlikely to be merely a consequence of their very high inferred magnetic
fields.

</DOC>
<DOC>
<DOCNO> 100866 </DOCNO>
Effective birationality of pluricanonical systems


  This is a sequal paper to math.AG/9909021. By using the theory of AZD
originated by the author, I prove that for every smooth projective $n$-fold $X$
of general type and every \[ m\geq \lceil\sum_{\ell =1}^{n}\sqrt[\ell]{2}
\ell\rceil +1, \] $\mid mK_{X}\mid$ gives a birational rational map from $X$
into a projective space, unless it has a nontrivial (relative dimension is
positive) rational fiber space structure whose general fiber is birational to a
variety of relatively low degree in a projective space.

</DOC>
<DOC>
<DOCNO> 70661 </DOCNO>
A Higgs or Not a Higgs?


  This talk summarizes a method for analyzing the properties of any new scalar
particle, which is systematic in the sense that it minimizes apriori
theoretical assumptions about the properties of the scalar particle, leading to
very model-independent results. This kind of analysis lends itself to
systematic survey through the terrain of candidate theories, which we find has
vast unpopulated areas. It is also useful for quantifying the comparison of the
goodness of fit of competing descriptions of data, should a new scalar be
found.

</DOC>
<DOC>
<DOCNO> 68497 </DOCNO>
Naturalness Re-examined: Implications for Supersymmetry Searches


  We discuss the origin of "focus points" in the scalar mass RGEs of the MSSM
and their implications for collider searches. We present a new exact analytic
solution to the homogeneous system of scalar mass RGEs in the MSSM for general
$\tan\beta$. This is then used to prove that the focus point for $m^2_{H_u}$
depends only on the value of the top Yukawa coupling at the {\em weak} scale
(not its value at the GUT scale) and is independent of the bottom Yukawa
coupling.

</DOC>
<DOC>
<DOCNO> 102710 </DOCNO>
Monotone Solutions of a Nonautonomous Differential Equation for a


  We study a class of integrodifferential equations and related ordinary
differential equations for the initial value problem of a rigid sphere falling
through an infinite fluid medium. We prove that for creeping Newtonian flow,
the motion of the sphere is monotone in its approach to the steady state
solution given by the Stokes drag. We discuss this property in terms of a
general nonautonomous second order differential equation, focusing on a
decaying nonautonomous term motivated by the sedimenting sphere problem.

</DOC>
<DOC>
<DOCNO> 67942 </DOCNO>
The most energetic particles in the universe


  Several issues related to the lensing of ultra-high energy cosmic rays by the
Galactic magnetic field are discussed.

</DOC>
<DOC>
<DOCNO> 117044 </DOCNO>
The beryllium atom and beryllium positive ion in strong magnetic fields


  The ground and a few excited states of the beryllium atom in external uniform
magnetic fields are calculated by means of our 2D mesh Hartree-Fock method for
field strengths ranging from zero up to 2.35*10^9T. With changing field
strength the ground state of the Be atom undergoes three transitions involving
four different electronic configurations which belong to three groups with
different spin projections S_z=0,-1,-2. For weak fields the ground state
configuration arises from the 1s^2 2s^2, S_z=0 configuration. With increasing
field strength the ground state evolves into the two S_z=-1 configurations
1s^22s 2p_{-1} and 1s^2 2p_{-1}3d_{-2}, followed by the fully spin polarised
S_z=-2 configuration 1s2p_{-1}3d_{-2}4f_{-3}. The latter configuration forms
the ground state of the beryllium atom in the high field regime \gamma>4.567.
The analogous calculations for the Be^+ ion provide the sequence of the three
following ground state configurations: 1s^22s and 1s^22p_{-1} (S_z=-1/2) and
1s2p_{-1}3d_{-2} (S_z=-3/2).

</DOC>
<DOC>
<DOCNO> 14098 </DOCNO>
Perturbative spectrum of Trapped Weakly Interacting Bosons in Two


  We study a trapped Bose-Einstein condensate under rotation in the limit of
weak, translational and rotational invariant two-particle interactions. We use
the perturbation-theory approach (the large-N expansion) to calculate the
ground-state energy and the excitation spectrum in the asymptotic limit where
the total number of particles N goes to infinity while keeping the total
angular momentum L finite. Calculating the probabilities of different
configurations of angular momentum in the exact eigenstates gives us a clear
view of the physical content of excitations. We briefly discuss the case of
repulsive contact interaction.

</DOC>
<DOC>
<DOCNO> 119067 </DOCNO>
Photometric Light Curves and Polarization of Close-in Extrasolar Giant


  The close-in extrasolar giant planets [CEGPs], $\ltorder$ 0.05 AU from their
parent stars, may have a large component of optically reflected light. We
present theoretical optical photometric light curves and polarization curves
for the CEGP systems, from reflected planetary light. Different particle sizes
of three condensates are considered. In the most reflective case, the
variability is $\approx 100$ micromagnitudes, which will be easily detectable
by the upcoming satellite missions MOST, COROT, and MONS, and possibly from the
ground in the near future. The least reflective case is caused by small, highly
absorbing grains such as solid Fe, with variation of much less than one
micromagnitude. Polarization for all cases is lower than current detectability
limits. We also discuss the temperature-pressure profiles and resulting
emergent spectra of the CEGP atmospheres. We discuss the observational results
of Tau Boo b by Cameron et al. (1999) and Charbonneau et al. (1999) in context
of our model results. The predictions - the shape and magnitude of the light
curves and polarization curves - are highly dependent on the size and type of
condensates present in the planetary atmosphere.

</DOC>
<DOC>
<DOCNO> 122867 </DOCNO>
A Gas-Kinetic Stability Analysis of Self-Gravitating and Collisional


  Linear theory is used to determine the stability of the self-gravitating,
rapidly (and nonuniformly) rotating, two-dimensional, and collisional
particulate disk against small-amplitude gravity perturbations. A gas-kinetic
theory approach is used by exploring the combined system of the Boltzmann and
the Poisson equations. The effects of physical collisions between particles are
taken into account by using in the Boltzmann kinetic equation a Krook model
integral of collisions modified to allow collisions to be inelastic. It is
shown that as a direct result of the classical Jeans instability and a secular
dissipative-type instability of small-amplitude gravity disturbances (e.g.
those produced by a spontaneous perturbation and/or a companion system) the
disk is subdivided into numerous irregular ringlets, with size and spacing of
the order of the Jeans length (= (4-6) mean epicyclic radius). The present
research is aimed above all at explaining the origin of various structures in
highly flattened, rapidly rotating systems of mutually gravitating particles.
In particular, it is suggested that forthcoming Cassini spacecraft
high-resolution images may reveal this kind of hyperfine of the order of 100 m
structure in the main rings A, B, and C of the Saturnian ring system.

</DOC>
<DOC>
<DOCNO> 151619 </DOCNO>
On noncommutative vacua and noncommutative solitons


  We consider noncommutative theory of a compact scalar field. The recently
discovered projector solitons are interpreted as classical vacua in the model
considered. Localized solutions to the projector equation are pointed out and
their brane interpretation is discussed. An example of the noncommutative
soliton interpolating between such vacua is given. No strong noncommutativity
limit is assumed.

</DOC>
<DOC>
<DOCNO> 69134 </DOCNO>
Confirmation of the $\sigma$-Meson below 1 GeV and Indication for the


  On the basis of a simultaneous description of the isoscalar s-wave channel of
the $\pi\pi$ scattering (from the threshold up to 1.9 GeV) and of the
$\pi\pi\to K\bar{K}$ process (from the threshold to $\sim$ 1.4 GeV) in the
model-independent approach, a confirmation of the $\sigma$-meson at $\sim$ 660
MeV and an indication for the glueball nature of the $f_0(1500)$ state are
obtained.

</DOC>
<DOC>
<DOCNO> 7825 </DOCNO>
Localized and Delocalized Charge Transport in Single-Wall


  We measured the complex dielectric constant in mats of single-wall
carbon-nanotubes between 2.7 K and 300 K up to 0.5 THz. The data are well
understood in a Drude approach with a negligible temperature dependence of the
plasma frequency (omega_p) and scattering time (tau) with an additional
contribution of localized charges. The dielectric properties resemble those of
the best ''metallic'' polypyrroles and polyanilines. The absence of metallic
islands makes the mats a relevant piece in the puzzle of the interpretation of
tau and omega_p in these polymers.

</DOC>
<DOC>
<DOCNO> 117600 </DOCNO>
The formation of bars and disks in Markarian starburst galaxies


  We have proposed in a companion paper (Considere et al. 2000) that bars
appeared recently in massive starburst nucleus galaxies. We now test this
hypothesis on an extended sample of barred and unbarred Markarian starburst
galaxies, using several samples of normal galaxies as control samples.
  In support of this hypothesis, we show that the proportion of barred galaxies
is much lower in Markarian starburst galaxies than in normal galaxies. In
addition to this deficiency of bars, we find that Markarian starburst galaxies
have smaller disks than normal galaxies, and that the disks of unbarred
starburst galaxies are smaller, on average, than barred ones. Finally, we show
that the Markarian starburst galaxies do not seem to follow the local
Tully--Fisher relation.
  Various alternatives are examined to explain the deficiency of bars and the
small disk dimensions in Markarian starburst galaxies. One possibility, which
is in agreement with the young bar hypothesis, is that the formation of disks
happens after the formation of bulges and that bars appear only later, when
enough gas has been accreted in the disk.

</DOC>
<DOC>
<DOCNO> 151480 </DOCNO>
Spinor representations of the Virasoro and super-Virasoro algebras for


  It is considered here the possibility of unitary spinor representations of
the Virasoro and super-Virasoro algebras for conformal spin to be equal 1/k; k
are integers.

</DOC>
<DOC>
<DOCNO> 85641 </DOCNO>
Newton's Constant isn't constant


  This article contains a brief pedagogical introduction to various
renormalization group related aspects of quantum gravity with an emphasis on
the scale dependence of Newton's constant and on black hole physics.

</DOC>
<DOC>
<DOCNO> 100714 </DOCNO>
A Free Probability Analogue of the Wasserstein Metric on the Trace-State


  We define a free probability analogue of the Wasserstein metric, which
extends the classical one. In dimension one, we prove that the square of the
Wasserstein distance to the semi-circle distribution is majorized by a modified
free entropy quantity.

</DOC>
<DOC>
<DOCNO> 7934 </DOCNO>
Increments of Uncorrelated Time Series Can Be Predicted With a Universal


  We present a simple and general result that the sign of the variations or
increments of uncorrelated times series are predictable with a remarkably high
success probability of 75% for symmetric sign distributions. The origin of this
paradoxical result is explained in details. We also present some tests on
synthetic, financial and global temperature time series.

</DOC>
<DOC>
<DOCNO> 117054 </DOCNO>
Perfectly secure cipher system


  We present a perfectly secure cipher system based on the concept of fake bits
which has never been used in either classical or quantum cryptography.

</DOC>
<DOC>
<DOCNO> 70450 </DOCNO>
Effects of $\Sigma$N channels on the Spin-Orbit Force in


  Effects of the $\Sigma$N channels on the spin-orbit force in
$\Lambda$-hypernuclei are investigated. It is found that the cancellation
between the symmetric and the antisymmetric $\Lambda$N spin-orbit force becomes
more complete when the contribution from the $\Sigma$N channels is included.
This may be the one of the reasons why the observed LS splitting of the
$\Lambda$ single particle energy is very small.

</DOC>
<DOC>
<DOCNO> 151815 </DOCNO>
Propagators for p-forms in AdS_{2p+1} and correlation functions in the


  In AdS_{2p+1} we construct propagators for p-forms whose lagrangians contain
terms of the form A / d A. In particular we explore the case of forms
satisfying ``self duality in odd dimensions'', and the case of forms with a
topological mass term. We point out that the ``complete'' set of maximally
symmetric bitensors previously used in all the other propagator papers is
incomplete - there exists another bitensor which can and does appear in the
formulas for the propagators in this particular case. Nevertheless, its
presence does not affect the other propagators computed so far.
  On the AdS side of the correspondence we compute the 2 and 3 point functions
involving the self-dual tensor of the maximal 7d gauged supergravity (sugra),
S_{\mu\nu\rho}. Since the 7 dimensional antisymmetric self-dual tensor obeys
first order field equations (S + * d S=0), to get a nonvanishing 2 point
function we add a certain boundary term (to satisfy the variational principle
on a manifold with boundary) to the 7d action. The 3 point functions we compute
are of the type SSB and SBB, describing vertex interactions with the gauge
fields B_{\mu}.

</DOC>
<DOC>
<DOCNO> 10273 </DOCNO>
Resistivity of a Metal between the Boltzmann Transport Regime and the


  We study the transport properties of a finite three dimensional disordered
conductor, for both weak and strong scattering on impurities, employing the
real-space Green function technique and related Landauer-type formula. The
dirty metal is described by a nearest neighbor tight-binding Hamiltonian with a
single s-orbital per site and random on-site potential (Anderson model). We
compute exactly the zero-temperature conductance of a finite size sample placed
between two semi-infinite disorder-free leads. The resistivity is found from
the coefficient of linear scaling of the disorder averaged resistance with
sample length. This ``quantum'' resistivity is compared to the semiclassical
Boltzmann expression computed in both Born approximation and multiple
scattering approximation.

</DOC>
<DOC>
<DOCNO> 71110 </DOCNO>
Signatures of Thermal Dilepton Radiation at RHIC


  The properties of thermal dilepton production from heavy-ion collisions in
the RHIC energy regime are evaluated for invariant masses ranging from 0.5 to 3
GeV. Using an expanding thermal fireball to model the evolution through both
quark-gluon and hadronic phases various features of the spectra are addressed.
In the low-mass region, due to an expected large background, the focus is on
possible medium modifications of the narrow resonance structures from $\omega$
and $\phi$ mesons, whereas in the intermediate-mass region the old idea of
identifying QGP radiation is reiterated including effects of chemical
under-saturation in the early stages of central Au+Au collisions.

</DOC>
<DOC>
<DOCNO> 9613 </DOCNO>
Bose-Einstein Condensation of Excitons: Reply to Tikhodeev's Criticism


  The extended version of our reply to Comment on ``Critical Velocities in
Exciton Superfluidity'' by S. G. Tikhodeev (Phys. Rev. Lett., 84 (2000), 3502
or from http://prl.aps.org/) is presented here. The principal question is
discussed: does the moving exciton-phonon packet contain the coherent
`nucleus', or the exciton-phonon condensate?

</DOC>
<DOC>
<DOCNO> 80735 </DOCNO>
An illustration of chiral fermions on a 1+1 dimensional lattice


  The vectorlike doubling of low-energy excitations is in fact a natural
consequence of the pair-production around the zero-energy (E=0) due to the
quantum field fluctuations of the lattice regularized vacuum. On the 1+1
dimensional lattice, we study an anomaly-free chiral model (11112) of four
left-movers and one right-mover with strong interactions. Exact computations of
relevant S-matrices illustrate that for high-momentum states, a negative
energy-gap (E<0) develops; the bound state and its constituents, which have the
same quantum numbers but opposite chiralities, fill the same energy-state so
that chiral symmetries are preserved; for low-momentum states, the negative
energy-gap vanishes and the bound state dissolves into its constituents near
zero energy. As a consequence of the gauge-anomaly cancellation and the index
theorem for flavor-singlet anomalies, the net number of zero-modes pushed down
into and pumped out from the zero-energy level by the gauge field is zero.

</DOC>
<DOC>
<DOCNO> 117217 </DOCNO>
Newton's aether model


  Isaac Newton is usually associated with the idea of absolute space and time,
and with ballistic light-corpuscle arguments. However, Newton was also a
proponent of wave/particle duality, and published a "new" variable-density
aether model in which light and matter trajectories were either bent by
gravitational fields, or deflected by an aether density gradient. Newton's
(flawed) aether model can be considered as an early attempt at a curved-space
model of gravity.

</DOC>
<DOC>
<DOCNO> 120153 </DOCNO>
Dynamics of the Galaxy's Satellites


  The Milky Way's satellites provide unique information about the density of
the Galactic halo at large radii. The inclusion of even a few rather inaccurate
proper motions resolves an ambiguity in older mass estimates in favour of
higher values. Many of the satellites are concentrated into streams. The
dynamics of the Magellanic Stream provided an early indication that the halo
reaches out to beyond 100 kpc. Tidal forces between the Clouds are currently
disturbing the Clouds' internal dynamics. One would expect this damage to
worsen rapidly as the tidal field of the MW excites the eccentricity of the
Clouds' mutual orbit. This process, which has yet to be completely modelled, is
important for understanding the degree of self-lensing in searches for
gravitational lensing events. The Sagittarius Dwarf galaxy very likely
contributes significantly to the Galactic warp. The direction of the warp's
line of nodes is incorrectly predicted by the simplest models of the Dwarf's
orbit. More sophisticated models, in which a complex distribution of stripped
dark matter is predicted, may be more successful.

</DOC>
<DOC>
<DOCNO> 70069 </DOCNO>
Thermal Green Functions in Coordinate Space for Massless Particles of


  The thermal Wightman functions for free, massless particles of spin 0, 1/2,
1, 3/2, and 2 are computed directly in coordinate space by solving the
appropriate differential equation and imposing the Kubo-Martin-Schwinger
condition. The solutions are valid for real, imaginary, or complex time. The
Wightman functions for spin 1 gauge bosons and for spin 2 gravitons are
directly related to the fundamental functions for spin 0. The Wightman
functions for spin 3/2 gravitinos is directly related to that for spin 1/2
fermions. Calculations for spin 1, 3/2, and 2 are done in covariant gauges. In
the deep space-like region the Wightman functions for bosons fall like $T/r$
whereas those for the fermions fall exponentially. In the deep time-like region
all the Wightman functions fall exponentially.

</DOC>
<DOC>
<DOCNO> 119014 </DOCNO>
A measurement at the first acoustic peak of the CMB with the 33 GHz


  This paper presents the results from the Jodrell Bank-IAC two-element 33 GHz
interferometer operated with an element separation of 32.9 wavelengths and
hence sensitive to 1 deg scale structure on the sky. The level of CMB
fluctuations, assuming a flat CMB spatial power spectrum over the range of
multipoles l = 208 +- 18, was found using a likelihood analysis to be \Delta
T_l = 63^{+7}_{-6} mu K at the 68% confidence limit, after the subtraction of
the contribution of monitored point sources. Other possible foreground
contributions have been assessed and are expected to have negligible impact on
this result.

</DOC>
<DOC>
<DOCNO> 100851 </DOCNO>
On the topology of scalar-flat manifolds


  Let $M$ be a simply-connected closed manifold of dimension $\geq 5$ which
does not admit a metric with positive scalar curvature. We give necessary
conditions for $M$ to admit a scalar-flat metric. These conditions involve the
first Pontrjagin class and the cohomology ring of $M$. As a consequence any
simply-connected scalar-flat manifold of dimension $\geq 5$ with vanishing
first Pontrjagin class admits a metric with positive scalar curvature. We also
describe some relations between scalar-flat metrics, almost complex structures
and the free loop space.

</DOC>
<DOC>
<DOCNO> 120717 </DOCNO>
Resolving Gamma-Ray Burst 000301C with a Gravitational Microlens


  The afterglow of the Gamma-Ray Burst (GRB) 000301C exhibited achromatic,
short time-scale variability that is difficult to reconcile with the standard
relativistic shock model. We interpret the observed light curves as a
microlensing event superimposed on power-law flux decays typical of afterglows.
In general, a relativistic GRB shock appears on the sky as a thin ring
expanding at a superluminal speed. Initially the ring is small relative to its
angular separation from the lens and so its flux is magnified by a constant
factor. As the ring grows and sweeps across the lens its magnification reaches
a maximum. Subsequently, the flux gradually recovers its unlensed value. This
behavior involves only three free parameters in its simplest formulation and
was predicted theoretically by Loeb & Perna (1998). Fitting the available
R-band photometric data of GRB 000301C to a simple model of the microlensing
event and a broken power-law for the afterglow, we find reasonable values for
all the parameters and a reduced chi^2/DOF parameter of 1.48 compared with 2.99
for the broken power-law fit alone. The peak magnification of ~2 occurred 3.8
days after the burst. The entire optical-IR data imply a width of the GRB ring
of order 10% of its radius, similar to theoretical expectations. The angular
resolution provided by microlensing is better than a micro-arcsecond. We infer
a mass of approximately 0.5 M_Sun for a lens located half way to the source at
z_s=2.04. A galaxy 2'' from GRB 000301C might be the host of the stellar lens,
but current data provides only an upper-limit on its surface brightness at the
GRB position.

</DOC>
<DOC>
<DOCNO> 178559 </DOCNO>
The p(d,p)d and p(d,p)pn reactions as a tool for the study of the short


  In recent time the deuteron structure at short distances is often treated
from the point of view nonnucleonic degrees of freedom. In this paper the
measurements of T-odd polarization observables using tensor polarized deuteron
beam and polarized proton target or proton polarimeter are proposed to search
the quark configurations inside the deuteron.

</DOC>
<DOC>
<DOCNO> 170305 </DOCNO>
Long distance entanglement based quantum key distribution


  A detailled analysis of quantum key distribution employing entangled states
is presented. We tested a system based on photon pairs entangled in energy-time
optimized for long distance transmission. It is based on a Franson type set-up
for monitoring quantum correlations, and uses a protocol analogous to BB84.
Passive state preparation is implemented by polarization multiplexing in the
interferometers. We distributed a sifted key of 0.4 Mbits at a raw rate of 134
Hz and with an error rate of 8.6% over a distance of 8.5 kilometers. We discuss
thoroughly the noise sources and practical difficulties associated with
entangled states systems. Finally the level of security offered by this system
is assessed and compared with that of faint laser pulses systems.

</DOC>
<DOC>
<DOCNO> 118311 </DOCNO>
High-resolution spectroscopy of V854 Cen in decline - Absorption and


  High-resolution optical spectra of the R Coronae Borealis (RBC) star V854
Centauri in the early stages of a decline show, in addition to the features
reported for other RCBs in decline, narrow absorption lines from the C_2
Phillips system. The low rotational temperature, T_rot = 1150K, of the C_2
ground electronic state suggests the cold gas is associated with the developing
shroud of carbon dust. These absorption lines were not seen at a fainter
magnitude on the rise from minimum light nor at maximum light. This is the
first detection of cold gas around a RCB star.

</DOC>
<DOC>
<DOCNO> 100251 </DOCNO>
Adelic Formulas for Gamma and Beta Functions of One-Class Quadratic


  Regularized adelic formulas for gamma and beta functions for arbitrary
quasicharacters (either ramified or not) and in an arbitrary field of algebraic
numbers are concretized as applied to one-class quadratic fields (and to the
field of rational numbers). Applications to 4-tachyon tree string amplitudes,
to the Veneziano (open strings) and Virasoro (closed strings) amplitudes as
well as to massless 4-particle amplitudes of the Ramond-Neveu-Schwarz
superstring and a heterotic string are discussed. Certain relations between
different superstring amplitudes are established.

</DOC>
<DOC>
<DOCNO> 152380 </DOCNO>
Norcor vs the Abominable Gauge Completion


  We use normal coordinate methods to obtain the expansion with respect to
fermionic coordinates of the 11-dimensional supermembrane action in a
supergravity background. Likewise, expansions for various branes in other
dimensions can be obtained. These methods allow a systematic and unambiguous
expansion of the vielbein to any order in the fermionic coordinates and avoid
the complications encountered in the gauge completion approach.

</DOC>
<DOC>
<DOCNO> 13205 </DOCNO>
Magnetic Field Effect for Two Electrons in a Two Dimensional Random


  We study the problem of two particles with Coulomb repulsion in a
two-dimensional disordered potential in the presence of a magnetic field. For
the regime, when without interaction all states are well localized, it is shown
that above a critical excitation energy electron pairs become delocalized by
interaction. The transition between the localized and delocalized regimes goes
in the same way as the metal-insulator transition at the mobility edge in the
three dimensional Anderson model with broken time reversal symmetry.

</DOC>
<DOC>
<DOCNO> 178472 </DOCNO>
Nucleon-nucleon interaction: Central potential and pion production


  We show that the tail of the chiral two-pion exchange nucleon-nucleon
potential is proportional to the $\pi N$ scalar form factor and discuss how it
can be translated into effective scalar meson interactions. We then construct a
kernel for the process $NN\to\pi NN$, due to the exchange of two pions, which
may be used in either three body forces or pion production in NN scattering.
Our final expression involves a partial cancellation among three terms, due to
chiral symmetry, but the net result is still important. We also find that, at
large internucleon distances, the kernel has the same spatial dependence as the
central NN potential and we produce expressions relating these processes
directly.

</DOC>
<DOC>
<DOCNO> 120490 </DOCNO>
Rotation, Statistical Dynamics and Kinematics of Globular Clusters


  Evolution with mass segregation and the evolution of the rotation of cores
are both discussed for self-similar core collapse. Evolution with angular
velocity proportional to the square root of the density is predicted. On the
Dynamical Main Sequence of globular clusters the energy emission from binaries
balances the energy expended in expanding the halo.
  Newton's exactly solved N-body problem is then given, along with recent
generalisations, all of which have no violent relaxation, but a new type of
statistical equilibrium is discussed.
  Finally, we set the creation of streams in the Galaxy's halo in the
historical context of their discovery.

</DOC>
<DOC>
<DOCNO> 120534 </DOCNO>
Measurements of Tidal Tail Populations Designed to Optimize Their Use as


  The launching of up to four astrometric missions in the next decade will
enable us to make measurements of stars in tidal streamers from Galactic
satellites of sufficient accuracy to place strong constraints on the mass
distribution in the Milky Way. In this paper we simulate observations of debris
populations in order to assess the required properties of any data set chosen
to implement this experiment. We apply our results to find the desired target
properties of stars (e.g., accuracy of velocity and proper motion measurements)
associated with the dwarf spheroidal satellites of the Milky Way.

</DOC>
<DOC>
<DOCNO> 120974 </DOCNO>
85-GHz BIMA observations of the double-hotspot radio galaxy 3C20


  We present 85-GHz observations of the archetypal double-hotspot radio source
3C20 made with the BIMA millimetre array. The resolution of BIMA allows us to
separate the two components of the eastern hotspot. By comparing the BIMA
observations with existing VLA data, we show that the spectra of the two
hotspot components are very similar, despite the clear differences in their
radio structure and their wide separation. We discuss the implications for
models of double hotspot formation. Weak emission from the lobes of 3C20 is
detected at 85 GHz, at a level consistent with the predictions of standard
spectral ageing models.

</DOC>
<DOC>
<DOCNO> 67772 </DOCNO>
Ultra High Energy Cosmic Rays from Cosmological Relics


  The current status of origin of Ultra High Energy Cosmic Rays (UHECR) is
reviewed, with emphasis given to elementary particle solutions to UHECR
problem, namely to Topological Defects and Super-Heavy Dark Matter (SHDM)
particles. The relic superheavy particles are very efficiently produced at
inflation. Being protected by gauge discrete symmetries, they can be long
lived. They are clustering in the Galactic halo, producing thus UHECR without
Greisen-Zatsepin-Kuzmin cutoff. Topological Defects can naturally produce
particles with energies as observed and much higher, but in most cases fail to
produce the observed fluxes. Cosmic necklaces, monopoles connected by strings
and vortons are identified as most plausible sources. The latter two of them
are also clustering in the halo and their observational predictions are
identical to those of SHDM particles.

</DOC>
<DOC>
<DOCNO> 71042 </DOCNO>
Higher-order QCD corrections to $\gamma^*\gamma^*\to hadrons$


  I illustrate the techniques and the results of the computation of order-$\as$
corrections to the production of hadrons in the collision of two virtual
photons, that originate from the incoming leptons at $\epem$ colliders.

</DOC>
<DOC>
<DOCNO> 12656 </DOCNO>
Ab initio calculations of response properties including electron-hole


  We discuss the current status of a computational approach which allows to
evaluate the dielectric matrix, and hence electronic excitations like optical
properties, including local field and excitonic effects. We introduce a recent
numerical development which greatly reduces the use of memory in such type of
calculations, and hence eliminates one of the bottlenecks for the application
to complex systems. We present recent applications of the method, focusing our
interest on insulating oxides.

</DOC>
<DOC>
<DOCNO> 9895 </DOCNO>
Critical values for a non-attractive lattice gas model


  We investigate numerically the critical behaviour of a one-dimensional
non-attractive lattice gas model that is the continuous-time version of the
Domany-Kinzel cellular automaton in one of its parameter subspaces. The model
shows a phase transition in the directed percolation universality class of
critical behaviour, as expected.

</DOC>
<DOC>
<DOCNO> 69773 </DOCNO>
Upper bound on the scale of Majorana-neutrino mass generation


  We derive a model-independent upper bound on the scale of Majorana-neutrino
mass generation. The upper bound is $4\pi v^2/\sqrt 3 m_\nu$, where $v \simeq
246$ GeV is the weak scale and $m_\nu$ is the Majorana neutrino mass. For
neutrino masses implied by neutrino oscillation experiments, all but one of
these bounds are less than the Planck scale, and they are all within a few
orders of magnitude of the grand-unification scale.

</DOC>
<DOC>
<DOCNO> 152162 </DOCNO>
Pseudoconformal field theory at the "wrong level"


  Pseudoaffine theories are characterized by formal replacement of the level to
the fractional number: $k\to\frac{k}{q}$, where $q$ is integer strange to
$k(g+k)$ ($g$ - dual Coxeter number). An example of "forbidden" $q$ is
considered (SU(2), $q=2$). The fusions of obtained theory are similar to the
affine ones. Spectra of minimal models are calculated.

</DOC>
<DOC>
<DOCNO> 152422 </DOCNO>
Some Issues in Noncommutative Solitons as D-branes


  We investigate and interpret a large class of soliton solutions found in
noncommutative tachyon condensation. These constructions make extensive use of
the idea that Dp-branes may be built out of lower dimensional branes. Finally
we comment on a recently proposed solution generating technique.

</DOC>
<DOC>
<DOCNO> 69841 </DOCNO>
Calculations with DLCQ


  The method of discrete light-cone quantization (DLCQ) and useful refinements
are summarized. Applications to various field theories are reviewed.

</DOC>
<DOC>
<DOCNO> 101671 </DOCNO>
Hodge theory on hyperbolic manifolds of infinite volume


  Let $Y=\Gamma\backslash H^n$ be a quotient of the hyperbolic space by the
action of a discrete convex-cocompact group of isometries. We describe certain
spaces of $\Gamma$-invariant currents on the sphere at infinity of $H^n$ with
support on the limit set of $\Gamma$. These spaces are finite-dimensional. The
main result identifies the cohomology of $Y$ with a quotient of such spaces. We
explain in which sense this result generalizes the classical Hodge theorem for
compact quotients. We obtain analogous results for the cohomology groups
$H^p(\Gamma,F)$, where $F$ is a finite-dimensional representation of the full
group of orientation preserving isometries of $H^n$.

</DOC>
<DOC>
<DOCNO> 151709 </DOCNO>
Duffin-Kemmer-Petiau Theory in the Causal Approach


  In this paper we consider the scalar sector of Duffin-Kemmer-Petiau theory in
the framework of Epstein-Glaser causal method. We calculate the lowest order
distributions for Compton scattering, vacuum polarization, self-energy and
vertex corrections. By requiring gauge invariance of the theory we recover, in
a natural way, the scalar propagator of the usual effective theory.

</DOC>
<DOC>
<DOCNO> 116246 </DOCNO>
Spacecraft & Gravity


  Anomalous deceleration of spacecraft hurtling through the Solar System may
have revealed a secret of Nature that gravity may run faster than light and
finite.

</DOC>
<DOC>
<DOCNO> 152387 </DOCNO>
Holographic renormalization group and conformal anomaly for AdS_9/CFT_8


  Holographic Renormalization Group (RG) in nine dimensions is considered. The
d8 holographic conformal anomaly is found. It should correspond to d8 CFT in
AdS_9/CFT_8 correspondence. The comparison of holographic and QFT anomalies in
d8 de Sitter space is done. It may give the indication for rigorous AdS_9/CFT_8
correspondence proposal.

</DOC>
<DOC>
<DOCNO> 40082 </DOCNO>
The excess of positive charges and the leading particles in DIS at HERA


  The charge of the leading particle in DIS interactions is studied with the
QCD models LEPTO, ARIADNE, RAPGAP and HERWIG. It is predicted to be
preferentially positive, as is expected from the modified quark parton model
and is studied over a wide range of x and Q^2.

</DOC>
<DOC>
<DOCNO> 14022 </DOCNO>
Heat transport and spin-charge separation in the normal state of high


  Hill et al. have recently measured both the thermal and charge conductivities
in the normal state of a high temperature superconductor. Based on the
vanishing of the Wiedemann-Franz ratio in the extrapolated zero temperature
limit, they conclude that the charge carriers in this material are not
fermionic. Here I make a simple observation that the prefactor in the
temperature dependence of the measured thermal conductivity is unusually large,
corresponding to an extremely small energy scale $T_0 \approx 0.15$ K. I argue
that $T_0$ should be interpreted as a collective scale. Based on
model-independent considerations, I also argue that the experiment leads to two
possibilities: 1) The charge-carrying excitations are non-fermionic. And much
of the heat current is in fact carried by distinctive charge-neutral
excitations; 2) The charge-carrying excitations are fermionic, but a subtle
ordering transition occurs at $T_0$.

</DOC>
<DOC>
<DOCNO> 9349 </DOCNO>
Application of Statistical Physics to Politics


  The concept and technics of real space renormalization group are applied to
study majority rule voting in hierarchical structures. It is found that
democratic voting can lead to totalitarianism by keeping in power a small
minority. Conditions of this paradox are analyzed and singled out. Indeed
majority rule produces critical thresholds to absolute power. Values of these
thresholds can vary from 50% up to at least 77%. The associated underlying
mechanism could provide an explanation for both former apparent eternity of
communist leaderships as well as their sudden collapse.

</DOC>
<DOC>
<DOCNO> 116359 </DOCNO>
New Models of Bi-Vacuum, Corpuscle - Wave Duality and Superunification


  The new Dynamic Model of Wave-Corpuscle Duality elaborated is devoted to
analysis of the internal (hidden) parameters of elementary de Broglie waves
(waves B) and their interrelation with external, observable ones. Dynamic model
is based on assumption of alternative pulsation of sub-elementary particles,
between the corpuscular [C] and wave [W] phase, each of them representing
corresponding semiperiod of wave B. The triplets of sub-elementary particles
form the elementary particles. The model considers the positive and negative
vacuum as two 'oceans' of superfluid quantum liquid, composed from virtual
quanta of opposite energies. This interacting positive and negative vacuum,
termed BI-VACUUM, is an infinitive source of bi-vacuum bosons (BVB). The
spatial image of BVB is a pair of [rotor + antirotor] of opposite direction of
rotation in the energetic planes of positive and negative vacuum. Due to
impulse and energy compensation there are no size limitations for BVB. The
smallest BVB, corresponding to biggest bi-vacuum slit, may serve as a
'molecules' of bi-vacuum. The nonlocal properties of hierarchical system of BVB
are the consequence of their zero resulting impulse, responsible for their
infinitive virtual wave B length and corresponding scale of bi-vacuum Bose
condensation. 

</DOC>
<DOC>
<DOCNO> 118963 </DOCNO>
RXTE Studies of Cyclotron Lines in Accreting Pulsars


  In this paper, we summarize the RXTE measurements of cyclotron resonance
scattering features in 8 accreting pulsars. The wide bandpass and modest
resolution of the RXTE instruments make them ideal for measuring these
generally broad features. In particular, the high energy response of HEXTE
provides a window for discovery of new lines not detectable with proportional
counters such as Ginga or the PCA alone.

</DOC>
<DOC>
<DOCNO> 71158 </DOCNO>
Direct CP Violation in Nonleptonic Kaon Decays by an Effective Chiral


  A self-consistent analysis of K->2pi and K->3pi decays within a unique
framework of chiral dynamics applied to the QCD-corrected weak nonleptonic
quark lagrangian has been performed. The results on K->2pi amplitudes at
O(p^6), including the value for epsilon'/epsilon, are compared with the
experiment to fix phenomenological B-factors for mesonic matrix elements of
nonpenguin and penguin four-quark operators. The dependence of B-factors on
different theoretical uncertainties and experimental errors of various input
parameters is investigated. Finally, we present our estimates at O(p^6) for the
CP-asymmetry of linear slope parameters in the K(+-)->3pi Dalitz plot.

</DOC>
<DOC>
<DOCNO> 12152 </DOCNO>
Exact bounds on the ground-state energy of the infinite-U Hubbard model


  We give upper and lower bounds for the ground-state energy of the infinite-U
Hubbard model. In two dimensions, using these bounds we are able to rule out
the possibility of phase separation between the undoped-insulating state and an
hole-rich state.

</DOC>
<DOC>
<DOCNO> 100212 </DOCNO>
The fractional - order controllers: Methods for their synthesis and


  This paper deals with fractional-order controllers. We outline mathematical
description of fractional controllers and methods of their synthesis and
application. Synthesis method is a modified root locus method for
fractional-order systems and fractional-order controllers. In the next section
we describe how to apply the fractional controller on control systems.

</DOC>
<DOC>
<DOCNO> 101603 </DOCNO>
The Randomness Recycler: A new technique for perfect sampling


  For many probability distributions of interest, it is quite difficult to
obtain samples efficiently. Often, Markov chains are employed to obtain
approximately random samples from these distributions. The primary drawback to
traditional Markov chain methods is that the mixing time of the chain is
usually unknown, which makes it impossible to determine how close the output
samples are to having the target distribution. Here we present a new protocol,
the randomness recycler (RR), that overcomes this difficulty. Unlike classical
Markov chain approaches, an RR-based algorithm creates samples drawn exactly
from the desired distribution. Other perfect sampling methods such as coupling
from the past use existing Markov chains, but RR does not use the traditional
Markov chain at all. While by no means universally useful, RR does apply to a
wide variety of problems. In restricted instances of certain problems, it gives
the first expected linear time algorithms for generating samples. Here we apply
RR to self-organizing lists, the Ising model, random independent sets, random
colorings, and the random cluster model.

</DOC>
<DOC>
<DOCNO> 84138 </DOCNO>
Dynamical study of the empty Bianchi type I model in generalised


  A dynamical study of the generalised scalar-tensor theory in the empty
Bianchi type I model is made. We use a method from which we derive the sign of
the first and second derivatives of the metric functions and examine three
different theories that can all tend towards relativistic behaviours at late
time. We determine conditions so that the dynamic be in expansion and
decelerated at late time.

</DOC>
<DOC>
<DOCNO> 102753 </DOCNO>
A Free Boundary Problem in the Theory of the Stars


  We investigate numerically models of the static spherically symmetric
boson-fermion stars in the scalar-tensor theory of gravity with massive dilaton
field. The proper mathematical model of such stars is interpreted as a
nonlinear two-parametric eigenvalue problem with unknown internal boundary. To
solve this problem the Continuous Analogue of Newton Method is used.

</DOC>
<DOC>
<DOCNO> 150786 </DOCNO>
Noncommutative Solitons


  We find classically stable solitons (instantons) in odd (even) dimensional
scalar noncommutative field theories whose scalar potential, $V(\ph)$, has at
least two minima. These solutions are bubbles of the false vacuum whose size is
set by the scale of noncommutativity. Our construction uses the correspondence
between non-commutative fields and operators on a single particle Hilbert
space. In the case of noncommutative gauge theories we note that expanding
around a simple solution shifts away the kinetic term and results in a purely
quartic action with linearly realised gauge symmetries.

</DOC>
<DOC>
<DOCNO> 121690 </DOCNO>
Two New Ejecta-Dominated Galactic Supernova Remnants: G337.2-0.7 and


  We present the analysis of new X-ray observations of two Galactic radio
supernova remnants (SNRs), G337.2-0.7 and G309.2-0.6. Both remnants exhibit
line-rich thermal spectra that require highly non-solar elemental abundance
ratios. In each case, Si and S are unequivocally overabundant compared to solar
based purely on the measured equivalent width of the K$\alpha$ line complex.
Detailed nonequilibrium ionization spectral analysis of these remnants, using a
single temperature, single ionization age model, confirm the overabundances,
yielding Si, S and Ar abundances many times their solar values: 3 to 5 times
solar for G337.2-0.7 and greater than 3 to 10 times solar for G309.2-0.6. We
also find that for both remnants, Ne and Mg are underabundant relative to Si,
and for G309.2-0.6, Ca and Fe as well are relatively underabundant. This is the
first detection of metal-rich, non-solar abundance material in these remnants,
identifying them as young ejecta-dominated SNRs. Further support for their
youth comes from the distances that we estimate from the fitted column
densities (less than 15 kpc for G337.2-0.7, and $4 \pm 2$ kpc for G309.2-0.6).
  From the implied sizes of the remnants at these distances we infer relatively
young ages (2000 to 4500 years for G337.2-0.7, and 700 to 4000 years for
G309.2-0.6). Finally we note that no compact object has yet been found within
G337.2-0.7, but an X-ray point source is evident within the radio shell of
G309.2-0.6, although its nature remains unknown.

</DOC>
<DOC>
<DOCNO> 116987 </DOCNO>
Investigations of Slow Motions of the SLAC Linac Tunnel


  Investigations of slow transverse motion of the linac tunnel of the Stanford
Linear Collider have been performed over period of about one month in December
1999 -- January 2000. The linac laser alignment system, equipped with a
quadrant photodetector, allowed submicron resolution measurement of the motion
of the middle of the linac tunnel with respect to its ends. Measurements
revealed two major sources responsible for the observed relative motion.
Variation of the external atmospheric pressure was found to be the most
significant cause of short wavelength transverse motion of the tunnel. The long
wavelength component of the motion has been also observed to have a large
contribution from tidal effects. The measured data are essential for
determination of parameters for the Next Linear Collider.

</DOC>
<DOC>
<DOCNO> 9282 </DOCNO>
Slabs of stabilized jellium: Quantum-size and self-compression effects


  We examine thin films of two simple metals (aluminum and lithium) in the
stabilized jellium model, a modification of the regular jellium model in which
a constant potential is added inside the metal to stabilize the system for a
given background density. We investigate quantum-size effects on the surface
energy and the work function. For a given film thickness we also evaluate the
density yielding energy stability, which is found to be slightly higher than
the equilibrium density of the bulk system and to approach this value in the
limit of thick slabs. A comparison of our self-consistent calculations with the
predictions of the liquid-drop model shows the validity of this model.

</DOC>
<DOC>
<DOCNO> 151967 </DOCNO>
Free Field Appoach to String Theory on AdS_3


  We discuss the correlation functions of the SL(2,C)/SU(2) WZW model, or the
CFT on the Euclidean AdS_3. We argue that their calculation is reduced to that
of a free theory by taking into account the renormalization and integrating out
a certain zero-mode, which is an analog of the zero-mode integration in
Liouville theory. Based on the resultant free field picture, we give a simple
prescription for calculating the correlation functions. The known exact two-
and three-point functions of generic primary fields are correctly obtained,
including numerical factors. We also obtain some four-point functions of
primaries by solving the Knizhnik-Zamolodchikov equation, and verify that our
prescription indeed gives them.

</DOC>
<DOC>
<DOCNO> 150518 </DOCNO>
Holography and T-duality


  We use the AdS/SYM correspondence to study the relevant effects of
compactified dimensions on the D-brane dynamics. We present a detailed picture
of the T-duality transition between branes in type IIA and type IIB
supergravity. An analysis of the renormalization scheme coming from the
expectation values of background fields and the role of Wilson lines in it is
given. We finally explore finite size effects and T-duality maps on the
description of Wilson loops by supergravity.

</DOC>
<DOC>
<DOCNO> 121901 </DOCNO>
X-ray Line Emission from the Hot Stellar Wind of theta 1 Ori C


  We present a first emission line analysis of a high resolution X-ray spectrum
of the stellar wind of theta 1 Ori C obtained with the High Energy Transmission
grating Spectrometer onboard the Chandra X-ray Observatory. The spectra are
resolved into a large number of emission lines from H- and He-like O, Ne, Mg,
Si, S, Ar and Fe ions. The He-like Fe XXV and Li-like Fe XXIV appear quite
strong indicating very hot emitting regions. From H/He flux ratios, as well as
from Fe He/Li emission measure ratios we deduce temperatures ranging from 0.5
to 6.1 x 10^7 K. The He-triplets are very sensitive to density as well. At
these temperatures the relative strengths of the intercombination and forbidden
lines indicate electron densities well above 10^12 cm^-3. The lines appear
significantly broadened from which we deduce a mean velocity of 770 km/s with a
spread between 400 and 2000 km/s. Along with results of the deduced emission
measure we conclude that the X-ray emission could originate in dense and hot
regions with a characteristic size of less then 4 x 10^10 cm.

</DOC>
<DOC>
<DOCNO> 10136 </DOCNO>
Spin transitions in a small Si quantum dot


  We have studied the magnetic field dependence of the ground state energies in
a small Si quantum dot. At low fields the first five electrons are added in a
spin-up -- spin-down sequence minimizing the total spin. This sequence does not
hold for larger number of electrons in the dot. At high fields the dot
undergoes transitions between states with different spins driven entirely by
Zeeman energy. We identify some features that can be attributed to transitions
between different spin configurations preserving the total spin of the dot. For
a few peaks we observed large linear shifts that correspond to the change of
the spin of the dot by 3/2. Such a change requires that an electron in the dot
flips its spin during every tunneling event.

</DOC>
<DOC>
<DOCNO> 67758 </DOCNO>
Event-by-Event Analysis and the Central Limit Theorem


  Event-by-event analysis of heavy-ion collision events is an important tool
for the study of the QCD phase boundary and formation of a quark-gluon plasma.
A universal feature of phase boundaries is the appearance of increased
fluctuations of conserved measures as manifested by excess measure variance
compared to a reference. In this paper I consider a particular aspect of EbyE
analysis emphasizing global-variables variance comparisons and the central
limit theorem. I find that the central limit theorem is, in a broader
interpretation, a statement about the scale invariance of total variance for a
measure distribution, which in turn relates to the scale-dependent symmetry
properties of the distribution.. I further generalize this concept to the
relationship between the scale dependence of a covariance matrix for all
conserved measures defined on a dynamical system and a matrix of covariance
integrals defined on two-point measure spaces, which points the way to a
detailed description of the symmetry dynamics of a complex measure system.
Finally, I relate this generalized description to several recently proposed or
completed event-by-event analyses.

</DOC>
<DOC>
<DOCNO> 9974 </DOCNO>
Error-correcting code on a cactus: a solvable model


  An exact solution to a family of parity check error-correcting codes is
provided by mapping the problem onto a Husimi cactus. The solution obtained in
the thermodynamic limit recovers the replica symmetric theory results and
provides a very good approximation to finite systems of moderate size. The
probability propagation decoding algorithm emerges naturally from the analysis.
A phase transition between decoding success and failure phases is found to
coincide with an information-theoretic upper bound. The method is employed to
compare Gallager and MN codes.

</DOC>
<DOC>
<DOCNO> 84617 </DOCNO>
Classical and Quantum Surgery of Geometries in an Open Inflationary


  We study classically and quantum mechanically the Euclidean geometries
compatible with an open inflationary universe of a Lorentzian geometry. The
Lorentzian geometry of the open universe with an ordinary matter state matches
either an open or a closed Euclidean geometry at the cosmological singularity.
With an exotic matter state it matches only the open Euclidean geometry and
describes a genuine instanton regular at the boundary of a finite radius. The
wave functions are found that describe the quantum creation of the open
inflationary universe.

</DOC>
<DOC>
<DOCNO> 170136 </DOCNO>
Thresholds for Linear Optics Quantum Computation


  We previously established that in principle, it is possible to quantum
compute using passive linear optics with photo-detectors (quant-ph/0006088).
Here we describe techniques based on error detection and correction that
greatly improve the resource and device reliability requirements needed for
scalability. The resource requirements are analyzed for ideal linear optics
quantum computation (LOQC). The coding methods can be integrated both with loss
detection and phase error-correction to deal with the primary relaxation
processes in non-ideal optics, including detector inefficiencies. The main
conclusion of our work is that the resource requirements for implementing
quantum communication or computation with LOQC are reasonable. Furthermore,
this work clearly demonstrates how special knowledge of the error behavior can
be exploited for greatly improving the fault tolerance and overheads of a
physical quantum computer.

</DOC>
<DOC>
<DOCNO> 119214 </DOCNO>
Gas properties of HII and Starburst galaxies: relation with the stellar


  We study the gas emission of galaxies with active star formation, consisting
mostly of HII galaxies and Starbursts, as well as some Seyfert 2s, and
determine chemical and physical parameters. The data consist of 19 high
signal-to-noise ratio optical templates, a result of grouping 185 emission line
galaxy spectra. Underlying stellar population models were subtracted from the
templates in order to isolate the pure emission component. We analyse the
distribution of these improved signal-to-noise ratio emission spectra in
diagnostic diagrams and find that the HII templates show a smaller spread in
log([OIII]/H\beta) values than the individual galaxies, apparently due to the
population subtraction and better signal-to-noise ratio. We thus suggest the
template sequence as a fiducial observational locus for HII galaxies which can
be used as reference for models. The sequence of line ratios presented by the
HII galaxies in the diagram log([OIII}]\lambda5007/H\beta) X
log([NII]\lambda6584/H\alpha) is primarily due to the gas metallicity, of which
the log([NII]/H\alpha) ratio is a direct estimator. We also study the
properties of the Starburst galaxies and those intermediate between HII and
Starburst galaxies, which are more metal rich and sit on more massive galaxies.
We discuss the present results in the frame of a recently proposed equivalent
width diagnostic diagram for emission line galaxies and conclude that the
observed ranges in W([OII])/W(H\beta) and W(H\beta) are mostly due to the
non-ionizing stellar population contribution. W(H\beta) can be used as an
estimator of this contribution to the continuum, and briefly discuss
implications to the cosmological use of HII galaxies.

</DOC>
<DOC>
<DOCNO> 10769 </DOCNO>
Chiral ordered phases in a frustrated S=1 chain with uniaxial


  The ground-state phase transitions of a frustrated S=1 Heisenberg chain with
the uniaxial single-ion-type anisotropy and the frustrating
next-nearest-neighbor coupling are studied. For the system, it has been shown
that there are gapless and gapped chiral phases in which the chirality \kappa_l
= S^x_l S^y_{l+1} - S^y_l S^x_{l+1} exhibits a finite long-range order (LRO)
and the spin correlation decays either algebraically or exponentially. In this
study, the transitions between the Haldane and chiral phase and between the
large-D (LD) and chiral phase are investigated using the infinite-system
density-matrix renormalization group method. It is found that there exist two
types of gapped chiral phases, "chiral Haldane" and "chiral LD" phases, in
which the string LRO coexists with the chiral LRO and the string correlation
decays exponentially, respectively.

</DOC>
<DOC>
<DOCNO> 150692 </DOCNO>
Symplectic Fermions


  We study two-dimensional conformal field theories generated from a
``symplectic fermion'' - a free two-component fermion field of spin one - and
construct the maximal local supersymmetric conformal field theory generated
from it. This theory has central charge c=-2 and provides the simplest example
of a theory with logarithmic operators.
  Twisted states with respect to the global SL(2,C)-symmetry of the symplectic
fermions are introduced and we describe in detail how one obtains a consistent
set of twisted amplitudes. We study orbifold models with respect to finite
subgroups of SL(2,C) and obtain their modular invariant partition functions. In
the case of the cyclic orbifolds explicit expressions are given for all two-,
three- and four-point functions of the fundamental fields. The C_2-orbifold is
shown to be isomorphic to the bosonic local logarithmic conformal field theory
of the triplet algebra encountered previously. We discuss the relation of the
C_4-orbifold to critical dense polymers.

</DOC>
<DOC>
<DOCNO> 69262 </DOCNO>
Probing the QCD pomeron in high-energy $\gamma^*\gamma^*$ collisions


  Based on the color dipole representation, we investigate consequences for the
$\gamma^{*}\gamma^{*},\gamma^{*}\gamma$ scattering of the finding by Fadin,
Kuraev and Lipatov that incorporation of asymptotic freedom into the BFKL
equation makes the QCD pomeron a series of isolated poles in the angular
momentum plane. We present parameter-free predictions for the vacuum exchange
contribution to the photon structure function which agree well with OPAL and L3
determinations. A good agreement is found between our predictions for the
energy and photon virtuality dependence of the photon-photon cross section
$\sigma^{\gamma^*\gamma^*}(W,Q^2,P^2)$ and the recent data taken by the L3
Collaboration.

</DOC>
<DOC>
<DOCNO> 121806 </DOCNO>
GRB 000926 and its optical afterglow: Another evidence for non-isotropic


  CCD Johnsons BV and Cousins RI photometric magnitudes are determined for 20
stars in the field of GRB 000926. Using them as calibrators, B and R band light
curves are constructed of the afterglow from ours and other published
observations. They show a steepening of the flux decay, from a decay constant
of 1.4+/-0.1 to 2.6+/-0.06 at about 1.7 days after the burst. Attributing this
break to the onset of sideways expansion of a jet-like ejecta, we estimate an
initial jet opening angle of ~0.14 radian, and a burst energy of ~10^51 erg. We
construct the X-ray-optical-near infrared spectrum of the afterglow and derive
a spectral index of ~ -0.9. From the spectrum we also estimate that the source
has a rather large intrinsic extinction, amounting to E(B-V)=0.36+/-0.02.

</DOC>
<DOC>
<DOCNO> 83492 </DOCNO>
Improving Performance of heavily loaded agents


  With the increase in agent-based applications, there are now agent systems
that support \emph{concurrent} client accesses. The ability to process large
volumes of simultaneous requests is critical in many such applications. In such
a setting, the traditional approach of serving these requests one at a time via
queues (e.g. \textsf{FIFO} queues, priority queues) is insufficient.
Alternative models are essential to improve the performance of such
\emph{heavily loaded} agents. In this paper, we propose a set of
\emph{cost-based algorithms} to \emph{optimize} and \emph{merge} multiple
requests submitted to an agent. In order to merge a set of requests, one first
needs to identify commonalities among such requests. First, we provide an
\emph{application independent framework} within which an agent developer may
specify relationships (called \emph{invariants}) between requests. Second, we
provide two algorithms (and various accompanying heuristics) which allow an
agent to automatically rewrite requests so as to avoid redundant work---these
algorithms take invariants associated with the agent into account. Our
algorithms are independent of any specific agent framework. For an
implementation, we implemented both these algorithms on top of the \impact
agent development platform, and on top of a (non-\impact) geographic database
agent. Based on these implementations, we conducted experiments and show that
our algorithms are considerably more efficient than methods that use the $A^*$
algorithm.

</DOC>
<DOC>
<DOCNO> 40342 </DOCNO>
Introduction to high$-p_T$ inclusives


  A selection of theoretical and experimental results are presented in the
broader context of understanding QCD and its relation to photon physics. A
phenomenological analysis of HERA data to constrain the gluon content of the
proton and photon is discussed. Measurements from the Tevatron and fixed-target
experiments are compared to theoretical predictions. Finally, the future of
higher order pQCD calculations is addressed.

</DOC>
<DOC>
<DOCNO> 10652 </DOCNO>
Probing Pauli Blocking Factors in Quantum Pumps with Broken


  A recently demonstrated quantum electron pump is discussed within the
framework of photon-assisted tunneling. Due to lack of time-reversal symmetry,
different results are obtained for the pump current depending on whether or not
final-state Pauli blocking factors are used when describing the tunneling
process. Whilst in both cases the current depends quadratically on the driving
amplitude for moderate pumping, a marked difference is predicted for the
temperature dependence. With blocking factors the pump current decreases
roughly linearly with temperature until k_B T ~ \hbar\omega is reached, whereas
without them it is unaffected by temperature, indicating that the entire Fermi
sea participates in the electronic transport.

</DOC>
<DOC>
<DOCNO> 69207 </DOCNO>
Measurement of Higgs Properties at the LHC


  A SM-like Higgs boson can be produced in a variety of channels at the LHC. By
combining information from production via gluon fusion and weak boson fusion,
various partial widths and the total Higgs boson width can be extracted.
Expected accuracies for 200 fb^{-1} of data are in the 10% range.

</DOC>
<DOC>
<DOCNO> 99992 </DOCNO>
Weak $\omega$-categories as $\omega$-hypergraphs


  In this paper, firstly, we introduce a higher-dimensional analogue of
hypergraphs, namely $\omega$-hypergraphs. This notion is thoroughly flexible
because unlike ordinary $\omega$-graphs, an n-dimensional edge called an n-cell
has many sources and targets. Moreover, cells have polarity, with which pasting
of cells is implicitly defined. As examples, we also give some known structures
in terms of $\omega$-hypergraphs. Then we specify a special type of
$\omega$-hypergraph, namely directed $\omega$-hypergraphs, which are made of
cells with direction. Finally, besed on them, we construct our weak
$\omega$-categories. It is an $\omega$-dimensional variant of the weak
n-categoreis given by Baez and Dolan. We introduce $\omega$-identical,
$\omega$-invertible and $\omega$-universal cells instead of universality and
balancedness of Baez-Dolan. The whole process of our definition is in parallel
with the way of regarding categories as graphs with composition and identities.

</DOC>
<DOC>
<DOCNO> 152129 </DOCNO>
Quantum-mechanical tunnelling and the renormalization group


  We explore the applicability of the exact renormalization group to the study
of tunnelling phenomena. We investigate quantum-mechanical systems whose energy
eigenstates are affected significantly by tunnelling through a barrier in the
potential. Within the approximation of the derivative expansion, we find that
the exact renormalization group predicts the correct qualitative behaviour for
the lowest energy eigenvalues. However, quantitative accuracy is achieved only
for potentials with small barriers. For large barriers, the use of alternative
methods, such as saddle-point expansions, can provide quantitative accuracy.

</DOC>
<DOC>
<DOCNO> 121635 </DOCNO>
The core-jet structure of the JVAS gravitational lens B1030+074


  We present results from VLBA+Effelsberg 1.7 GHz, VLBA 8.4 GHz and VLBA 15 GHz
observations of the JVAS gravitational lens system B1030+074. The
VLBA+Effelsberg 1.7 GHz data with 3 mas resolution reveal a detailed 60 mas jet
structure in the strong A component of the lens system and maybe a first hint
of the corresponding jet structure in the faint component B. As we go to the
higher resolution 8.4 GHz and 15 GHz data we can see more of the inner
structure of the A core, which is resolved, while the B core still remains
unresolved.

</DOC>
<DOC>
<DOCNO> 10706 </DOCNO>
Universality Classes of Self-Avoiding Fixed-Connectivity Membranes


  We present an analysis of extensive large-scale Monte Carlo simulations of
self-avoiding fixed-connectivity membranes for sizes (number of faces) ranging
from 512 to 17672 (triangular) plaquettes. Self-avoidance is implemented via
impenetrable plaquettes. We simulate the impenetrable plaquette model in both
three and four bulk dimensions. In both cases we find the membrane to be flat
for all temperatures: the size exponent in three dimensions is nu=0.95(5)
(Hausdorff dimension d_H=2.1(1)). The single flat phase appears, furthermore,
to be equivalent to the large bending rigidity phase of non-self-avoiding
fixed-connectivity membranes - the roughness exponent in three dimensions is
xi=0.63(4). This suggests that there is a unique universality class for flat
fixed-connectivity membranes without attractive interactions. Finally we
address some theoretical and experimental implications of our work.

</DOC>
<DOC>
<DOCNO> 117660 </DOCNO>
Non-Gaussianity and the recovery of the mass power spectrum from the


  We investigate the effect of non-Gaussianity on the reconstruction of the
initial mass field from the Ly$\alpha$ forest. We show that the transmitted
flux of QSO absorption spectra are highly non-Gaussian in terms of the
statistics, the kurtosis spectrum and scale-scale correlation. These
non-Gaussianities can not be completely removed by the conventional algorithm
of Gaussianization, and the scale-scale correlations are largely retained in
the mass field recovered by the Gaussian mapping. Therefore, the mass power
spectrum recovered by the conventional algorithm is systematically lower than
the initial mass spectrum on scales at which the local scale-scale correlation
is substantial. To reduce the non-Gaussian contamination, we present two
methods. The first is to perform the Gaussianization scale-by-scale using the
discrete wavelet transform (DWT) decomposition. We show that the non-Gaussian
features of the Ly$\alpha$ forest basically will no longer exist in the
scale-by-scale Gaussianized mass field. The second method is to choose a proper
orthonormal basis (representation) to suppress the effect of the non-Gaussian
correlations. In the quasilinear regime of cosmic structure formation, the DWT
power spectrum is efficient for suppressing the non-Gaussian contamination.
These two methods significantly improve the recovery of the mass power spectrum
from the Ly$\alpha$ forest.

</DOC>
<DOC>
<DOCNO> 10390 </DOCNO>
Normal-state pseudogap and electron flat dispersion in copper oxide


  The anomalous momentum and doping dependence of the electron spectral
function and electron dispersion for copper oxide materials in the underdoped
regime are studied within the t-J model. It is shown that the electron spectrum
is changed with dopings, and the electron dispersion exhibits a flat band
around ($\pi$,0) point in the Brillouin zone, which leads to the normal-state
pseudogap formation. The theoretical results are consistent with the
experiments and numerical simulations.

</DOC>
<DOC>
<DOCNO> 12338 </DOCNO>
Magnon scattering processes and low temperature resistivity in CMR


  Low temperature resistivity of CMR manganites is investigated. At the ground
state, conduction electrons are perfectly spin polarized, which is called
half-metallic. From one-magnon scattering processes, it is discussed that the
resistivity of a half metal as a function of temperature scales as rho(T) -
rho(0) propto T^3. We take (Nd,Tb,Sr)MnO_3 as an example to compare theory and
experiments. The result is in a good agreement.

</DOC>
<DOC>
<DOCNO> 100012 </DOCNO>
Values of Brownian intersection exponents II: Plane exponents


  We derive the exact value of intersection exponents between planar Brownian
motions or random walks, confirming predictions from theoretical physics by
Duplantier and Kwon. Let B and B' be independent Brownian motions (or simple
random walks) in the plane, started from distinct points. We prove that the
probability that the paths B[0,t] and B'[0,t] do not intersect decays like
t^{-5/8}. More precisely, there is a constant c>0 such that if |B(0) - B'(0)|
=1, for all t \ge 1, c^{-1} t^{-5/8} \le \P[ B[0,t] \cap B'[0,t] = \emptyset ]
\le c t^{-5/8}. One consequence is that the set of cut-points of B[0,1] has
Hausdorff dimension 3/4 almost surely. The values of other exponents are also
derived. Using an analyticity result, which is to be established in a
forthcoming paper, it follows that the Hausdorff dimension of the outer
boundary of B[0,1] is 4/3, as conjectured by Mandelbrot. The proofs are based
on a study of SLE_6 (stochastic Loewner evolution with parameter 6), a recently
discovered process which conjecturally is the scaling limit of critical
percolation cluster boundaries. The exponents of SLE_6 are calculated, and they
agree with the physicists' predictions for the exponents for critical
percolation and self-avoiding walks. From the SLE_6 exponents the Brownian
intersection exponents are then derived.

</DOC>
<DOC>
<DOCNO> 9590 </DOCNO>
Magnetic Foehn Effect in Nonadiabatic Transition


  The magnetization curves as a response of sweeping magnetic field in the
thermal environment are investigated using the quantum master equation. In a
slow velocity region where the system almost behaves adiabatically, the
magnetic plateau appears which has been observed in the recent experiment of
V$_{15}$ [ Phys. Rev. Lett. (2000)]. We investigate its mechanism and propose
that this phenomenon is quite universal in the quasi-adiabatic transition with
small inflow of the heat, and we call it 'Magnetic Foehn Effect'. We observe
the crossover between this mechanism and the Landau-Zener-St\"{u}ckelberg
mechanism changing the velocity. Some experiment is proposed to clarify the
inherent mechanism of this effect.

</DOC>
<DOC>
<DOCNO> 72024 </DOCNO>
Gluon distribution at moderately low-x from NMC deuteron structure


  We present some simple methods to find gluon distribution from analysis of
deuteron F_{2} structure function data at moderately low-x. Here we use the
leading order(LO) Altarelli -Parisi(AP) evolution equation and New Muon
Collaboration (NMC) deuteron F_{2} structure function data to extract gluon
distribution. We also compare our results with those of other authors.

</DOC>
<DOC>
<DOCNO> 9382 </DOCNO>
Statistical coarse-graining as an approach to multiscale problems in


  Multiscale phenomena which include several processes occuring simultaneously
at different length scales and exchanging energy with each other, are
widespread in magnetism. These phenomena often govern the magnetization
reversal dynamics, and their correct modeling is important. In the present
paper, we propose an approach to multiscale modeling of magnets, applying the
ideas of coarse graining. We have analyzed the choice of the weighting function
used in coarse graining, and propose an optimal form for this function. Simple
tests provide evidence that this approach may be useful for modeling of
realistic magnetic systems.

</DOC>
<DOC>
<DOCNO> 10892 </DOCNO>
High resolution infrared absorption spectra, crystal field, and


  High resolution low-temperature absorption spectra of 0.2% Pr^3+ doped
CsCdBr_3 were measured in the spectral region 2000--7000 cm-1. Positions and
widths of the crystal field levels within the 3H5, 3H4, 3F2, and 3F3 multiplets
of the Pr^3+ main center have been determined. Hyperfine structure of several
spectral lines has been found. Crystal field calculations were carried out in
the framework of the semiphenomenological exchange charge model (ECM).
Parameters of the ECM were determined by fitting to the measured total
splittings of the 3H4 and 3H6 multiplets and to the observed in this work
hyperfine splittings of the crystal field levels. One- and two-phonon
relaxation rates were calculated using the phonon Green's functions of the
perfect (CsCdBr_3) and locally perturbed (impurity dimer centers in
CsCdBr_3:Pr^3+) crystal lattice. Comparison with the measured linewidths
confirmed an essential redistribution of the phonon density of states in
CsCdBr_3 crystals doped with rare-earth ions.

</DOC>
<DOC>
<DOCNO> 71580 </DOCNO>
Sub-millimeter tests of the gravitational inverse-square law: A search


  Motivated by higher-dimensional theories that predict new effects, we tested
the gravitational 1/r^2 law at separations ranging down to 218 micrometers
using a 10-fold symmetric torsion pendulum and a rotating 10-fold symmetric
attractor. We improved previous short-range constraints by up to a factor of
1000 and find no deviations from Newtonian physics.

</DOC>
<DOC>
<DOCNO> 10127 </DOCNO>
Localization Effect in a 2D Superconducting Network without Disorder


  The superconducting properties of a two-dimensional superconducting wire
network with a new geometry have been measured as a function of the external
magnetic field. The extreme localization effect recently predicted for this
periodic lattice is revealed as a suppression of the critical current when the
applied magnetic field corresponds to half a flux quantum per unit cell. For
this particular magnetic field, the observed vortex state configuration is
highly disordered.

</DOC>
<DOC>
<DOCNO> 101546 </DOCNO>
Quantum Real Projective Space, Disc and Sphere


  We define the $C^*$-algebra of quantum real projective space $\R P_q^2$,
classify its irreducible representations and compute its $K$-theory. We also
show that the $q$-disc of Klimek-Lesniewski can be obtained as a non-Galois
$\Z_2$-quotient of the equator Podle\'s quantum sphere. On the way, we provide
the Cartesian coordinates for all Podle\'s quantum spheres and determine an
explicit form of isomorphisms between the $C^*$-algebras of the equilateral
spheres and the $C^*$-algebra of the equator one.

</DOC>
<DOC>
<DOCNO> 117310 </DOCNO>
Dynamical Properties and Plasmon Dispersion of a Weakly Degenerate


  Classical Molecular Dynamics (MD) simulations for a one-component plasma
(OCP) are presented. Quantum effects are included in the form of the Kelbg
potential. Results for the dynamical structure factor are compared with the
Vlasov and RPA (random phase approximation) theories. The influence of the
coupling parameter $\Gamma$, degeneracy parameter $\rho \Lambda^3$ and the form
of the pair interaction on the optical plasmon dispersion is investigated. An
improved analytical approximation for the dispersion of Langmuir waves is
presented.

</DOC>
<DOC>
<DOCNO> 121206 </DOCNO>
On the Spectroscopic Diversity of Type Ia Supernovae


  A comparison of the ratio of the depths of two absorption features in the
spectra of TypeIa supernovae (SNe Ia) near the time of maximum brightness with
the blueshift of the deep red Si II absorption feature 10 days after maximum
shows that the spectroscopic diversity of SNe Ia is multi-dimensional. There is
a substantial range of blueshifts at a given value of the depth ratio. We also
find that the spectra of a sample of SNe Ia obtained a week before maximum
brightness can be arranged in a ``blueshift sequence'' that mimics the time
evolution of the pre-maximum-light spectra of an individual SN Ia, the well
observed SN 1994D. Within the context of current SN Ia explosion models, we
suggest that some of the SNe Ia in our sample were delayed-detonations while
others were plain deflagrations.

</DOC>
<DOC>
<DOCNO> 70431 </DOCNO>
A Statistical Superfield. II. Some Further Predictions


  In an earlier paper, an action with unconventional supersymmetry was found to
reproduce standard physics at low energy, but to predict interesting new
phenomena near 1 TeV and above. In the present paper, it is shown that this
action results from a remarkably simple picture: a single fundamental system
consisting of identical ``bits'' which vary randomly over all possible states.
One finds that this picture leads first to a bosonic action with a randomly
fluctuating potential, and then to a supersymmetric action with exactly the
same form that was postulated earlier. Several new predictions are also given
here (for the simplest version of the present theory): (1) The only
superpartners are scalar bosons. (2) The most natural candidate for cold dark
matter is therefore a spin-zero WIMP. (3) The Higgs boson has an R-parity of
-1, so it can only be produced as one member of a pair of superpartners. (This
prediction is associated with a reinterpretation of Yukawa couplings.) (4) All
these fundamental scalar particles have an unconventional equation of motion.
Finally, it is shown that the present theory leads to a consistent description
in terms of quantized fields, and that the vacuum energy vanishes before
supersymmetry is broken.

</DOC>
<DOC>
<DOCNO> 100105 </DOCNO>
The braiding for representations of q-deformed affine $sl_2$


  We compute the braiding for the `principal gradation' of $U_q(\hat{{\it
sl}_2})$ for $|q|=1$ from first principles, starting from the idea of a rigid
braided tensor category. It is not necessary to assume either the crossing or
the unitarity condition from S-matrix theory. We demonstrate the uniqueness of
the normalisation of the braiding under certain analyticity assumptions, and
show that its convergence is critically dependent on the number-theoretic
properties of the number $\tau$ in the deformation parameter $q=e^{2\pi
i\tau}$. We also examine the convergence using probability, assuming a uniform
distribution for $q$ on the unit circle.

</DOC>
<DOC>
<DOCNO> 118038 </DOCNO>
Non-equilibrium H2 ortho-to-para ratio in two molecular clouds of the


  We present ISO observations of the S(0), S(1), S(2), and S(3) rotational
lines of molecular hydrogen from two molecular clouds near the Galactic Center
(GC). We have also measured continuum dust emission at infrared wavelengths
with ISO and the rotational radio lines J=1-0 of 13CO and C18O and J=2-1 of
C18O with the IRAM-30m telescope. Using the dust continuum spectra and the CO
lines we derive a total visual extinction of 15-20 magnitudes toward these GC
clouds. After correcting the H2 data for extinction, the gas temperatures are
\~250 K and the column densities of warm gas are ~2e21 cm-2. This is the first
direct measure of the H2 column densities of the warm component; with this, we
estimate an NH3 abundance in the warm gas of ~ 2e-7. The column density of warm
gas is, at least, a factor of 100 larger than the corresponding column
densities derived from the warm dust. The observed ortho-to-para ratio (OTPR)
is ~ 1, clearly below the local thermodynamical equilibrium (LTE) OTPR for gas
at 250 K of ~3. Low velocity shocks (~ 10 km/s) are the most likely explanation
for the column densities of warm gas and dust and the non-LTE H2 OTPR.

</DOC>
<DOC>
<DOCNO> 70218 </DOCNO>
Update on four-family neutrino oscillations at Neutrino Factory


  The prospects of measuring the leptonic angles and CP-odd phases at a {\em
neutrino factory} are discussed in the scenario of three active plus one
sterile neutrino, motivated by the $\nu_\mu \raw \nu_e$ LSND signal.
Sensitivity to the MNS mixing matrix angles at $O (10^{-3})$ is achieved with a
1 T detector at $\sim 1$ km from the source, whereas leptonic CP-violation can
be measured through tau detection with a 1 kT detector at $\sim 100$ km.

</DOC>
<DOC>
<DOCNO> 152419 </DOCNO>
Static Gauge Potential from Noncritical Strings


  The static gauge potential between heavy sources is computed from a recently
introduced non-critical bosonic string background. When the sources are located
at the infinity of the holographic coordinate, the linear dilaton behavior is
recovered, which means that the potential is exactly linear in the separation
between the sources. When the sources are moved towards the origin, a competing
overconfining cubic branch appears, which is however disfavored energetically.

</DOC>
<DOC>
<DOCNO> 100417 </DOCNO>
Linear repetitivity, I. Uniform subadditive ergodic theorems and


  This paper is concerned with the concept of linear repetitivity in the theory
of tilings. We prove a general uniform subadditive ergodic theorem for linearly
repetitive tilings. This theorem unifies and extends various known
(sub)additive ergodic theorems on tilings. The results of this paper can be
applied in the study of both random operators and lattice gas models on
tilings.

</DOC>
<DOC>
<DOCNO> 151768 </DOCNO>
Multiple vacua in two-dimensional Yang-Mills theory


  Two-dimensional SU(N) Yang-Mills theory is endowed with a non-trivial vacuum
structure (k-sectors). The presence of k-sectors modifies the energy spectrum
of the theory and its instanton content, the (Euclidean) space-time being
compactified on a sphere. For the exact solution, in the limit in which the
sphere is decompactified, a k-sector can be mimicked by the presence of
k-fundamental charges at infinity, according to a Witten's suggestion. However,
this property neither holds before decompactification nor for the genuine
perturbative solution which corresponds to the zero-instanton contribution on
the sphere.

</DOC>
<DOC>
<DOCNO> 101028 </DOCNO>
Critical exponents, conformal invariance and planar Brownian motion


  In this review paper, we first discuss some open problems related to
two-dimensional self-avoiding paths and critical percolation. We then review
some closely related results (joint work with Greg Lawler and Oded Schramm) on
critical exponents for two-dimensional simple random walks, Brownian motions
and other conformally invariant random objects.

</DOC>
<DOC>
<DOCNO> 70919 </DOCNO>
Comments on two papers by Kapusta and Wong


  We critically examine recently published results on the thermal production of
massive vector bosons in a quark-gluon plasma. We claim the production rate is
a collinear safe observable.

</DOC>
<DOC>
<DOCNO> 10960 </DOCNO>
On time's arrow in Ehrenfest models with reversible deterministic


  We introduce a deterministic, time-reversible version of the Ehrenfest urn
model. The distribution of first-passage times from equilibrium to
non-equilibrium states and vice versa is calculated. We find that average times
for transition to non-equilibrium always scale exponentially with the system
size, whereas the time scale for relaxation to equilibrium depends on
microscopic dynamics. To illustrate this, we also look at deterministic and
stochastic versions of the Ehrenfest model with a distribution of microscopic
relaxation times.

</DOC>
<DOC>
<DOCNO> 101204 </DOCNO>
Flux tube solutions in noncommutative gauge theories


  We derive nonperturbative classical solutions of noncommutative U(1) gauge
theory, with or without a Higgs field, representing static magnetic flux tubes
with arbitrary cross-section. The fields are nonperturbatively different from
the vacuum in at least some region of space. The flux of these tubes is
quantized in natural units. We also point out that magnetic monopole charge can
be fractionized by embedding the monopoles in a constant magnetic field.

</DOC>
<DOC>
<DOCNO> 118227 </DOCNO>
Spectral Analysis of the Lyman-Alpha Forest Using Wavelets


  It is shown how wavelets may be used to analyse the absorption properties of
the Lya forest. The Discrete Wavelet Transform of a QSO spectrum is used to
decompose the light fluctuations that comprise the forest into orthogonal
wavelets. It is demonstrated that most of the signal is carried by the moderate
to lower frequency wavelets in high resolution spectra, and that a
statistically acceptable description of even high signal-to-noise spectra is
provided by only a fraction (10-30%) of the wavelets. The distributions of the
wavelet coefficients provide a statistical basis for discriminating between
different models of the Lya forest. The method is illustrated using the
measured spectrum of Q1937-1009. The procedure described is readily automated
and may be used to process both measured spectra and the large number of
spectra generated by numerical simulations, permitting a fair comparison
between the two.

</DOC>
<DOC>
<DOCNO> 13758 </DOCNO>
Superconductivity on the threshold of magnetism in CePd2Si2 and CeIn3


  The magnetic ordering temperature of some rare earth based heavy fermion
compounds is strongly pressure-dependent and can be completely suppressed at a
critical pressure, p$_c$, making way for novel correlated electron states close
to this quantum critical point. We have studied the clean heavy fermion
antiferromagnets CePd$_2$Si$_2$ and CeIn$_3$ in a series of resistivity
measurements at high pressures up to 3.2 GPa and down to temperatures in the mK
region. In both materials, superconductivity appears in a small window of a few
tenths of a GPa on either side of p$_c$. We present detailed measurements of
the superconducting and magnetic temperature-pressure phase diagram, which
indicate that superconductivity in these materials is enhanced, rather than
suppressed, by the closeness to magnetic order.

</DOC>
<DOC>
<DOCNO> 69968 </DOCNO>
Predictions for Fermion Pair Production at e+e- Colliders


  We discuss the status and some ongoing upgrades of the ZFITTER program for
applications at e+e- colliders LEP1/SLC, LEP2, GigaZ, and TESLA. The inclusion
of top quark pair production is under work.

</DOC>
<DOC>
<DOCNO> 102126 </DOCNO>
A geometric spectral theory for n-tuples of self-adjoint operators in a


  Given an n-tuple {b_1, ..., b_n} of self-adjoint operators in a finite von
Neumann algebra M and a faithful, normal tracial state tau on M, we define a
map Psi from M to R^{n+1} by Psi(a) = (tau(a), tau(b_1a), ..., tau(b_na)). The
image of the positive part of the unit ball under Psi is called the spectral
scale of {b_1, .., b_n} relative to tau and is denoted by B. In a previous
paper with Nik Weaver we showed that the geometry of B reflects spectral data
for real linear combinations of the operators {b_1, .., b_n}. For example, we
showed that an exposed face in B is determined by a certain pair of spectral
projections of a real linear combination of {b_1, .., b_n}. In the present
paper we extend this study to faces that are not exposed. We completely
describe the structure of arbitrary faces of B in terms of {b_1, .., b_n} and
tau. We also study faces of convex, compact sets that are exposed by more than
one hyperplane of support. Although many of the conclusions of this study
involve too much notation to fit nicely in an abstract, there are two results
that give their flavor very well. Let N be the algebra generated by {b_1, ...,
b_n} and the identity. Theorem 6.1: If the set of extreme points of B is
countable, then N is abelian. Corollary 5.6: B has a finite number of extreme
points if and only if N is abelian and finite dimensional.

</DOC>
<DOC>
<DOCNO> 11878 </DOCNO>
Two-dimensional array of diffusive SNS junctions with high-transparent


  We report the first comparative study of the properties of two-dimensional
arrays and single superconducting film - normal wire - superconducting film
(SNS) junctions. The NS interfaces of our SNS junctions are really high
transparent, for superconducting and normal metal parts are made from the same
material (superconducting polycrystalline PtSi film). We have found that the
two-dimensional arrays reveal some novel features: (i) the significant
narrowing of the zero bias anomaly (ZBA) in comparison with single SNS
junctions, (ii) the appearance of subharmonic energy gap structure (SGS), with
up to n=16 (eV=\pm 2\Delta/n), with some numbers being lost, (iii) the
transition from 2D logarithmic weak localization behavior to metallic one. Our
experiments show that coherent phenomena governed by the Andreev reflection are
not only maintained over the macroscopic scale but manifest novel pronounced
effects as well. The behavior of the ZBA and SGS in 2D array of SNS junctions
strongly suggests that the development of a novel theoretical approach is
needed which would self-consistently take into account the distribution of the
currents, the potentials, and the superconducting order parameter.

</DOC>
<DOC>
<DOCNO> 151458 </DOCNO>
Gauge Symmetry As Symmetry Of Matrix Coordinates


  We propose a new point of view to gauge theories based on taking the action
of symmetry transformations directly on the coordinates of space. Via this
approach the gauge fields are not introduced at the first step, and they can be
interpreted as fluctuations around some classical solutions of the model. The
new point of view is connected to the lattice formulation of gauge theories,
and the parameter of noncommutativity of coordinates appears as the lattice
spacing parameter. Through the statements concerning the continuum limit of
lattice gauge theories, this suggestion arises that noncommutative spaces are
the natural ones to formulate gauge theories at strong coupling. Via this point
of view, a close relation between the large-N limit of gauge theories and
string theory can be manifested.

</DOC>
<DOC>
<DOCNO> 120099 </DOCNO>
Sunyaev-Zel'dovich Effect Review


  I review the present observational status of the SZ effect due to the Compton
scattering of the 3K background on the hot electrons of clusters of galaxies. I
raise the relevant issues from theoretical and X-ray aspects of the question
that challenge the present experiments. Future instruments like powerful radio
interferometers and bolometric cameras should give us access to the statistics
of clusters as well as their internal morphology within the next ten years.
They will provide an approach complementary to space experiments (XMM, Chandra,
Planck) for some fundamental cosmological and large scale structure issues.

</DOC>
<DOC>
<DOCNO> 170434 </DOCNO>
Lossless quantum coding in many-letter spaces


  Based on the concept of many-letter theory, an observable is defined
measuring the raw quantum information content of single messages. A general
characterization of quantum codes using the Kraus representation is given.
Compression codes are defined by their property of decreasing the expected raw
information content of a given message ensemble. Lossless quantum codes, in
contrast to lossy codes, provide the retrieval of the original data with
perfect fidelity. A general lossless coding scheme is given that translates
between two quantum alphabets. It is shown that this scheme is never
compressive. Furthermore, a lossless quantum coding scheme, analog to the
classical Huffman scheme but different from the Braunstein scheme, is
implemented, which provides optimal compression. Motivated by the concept of
lossless quantum compression, an observable is defined that measures the core
quantum information content of a particular message with respect to a given a
priori message ensemble. The average of this observable yields the von Neumann
entropy.

</DOC>
<DOC>
<DOCNO> 40033 </DOCNO>
Moller Scattering Polarimetry for High Energy e^+e^- Linear Colliders


  The general features of the Moller scattering and its use as an electron
polarimeter are described and studied in view of the planned future high energy
e^+e^- linear colliders. In particular the study concentrates on the TESLA
collider which is envisaged to operate with longitudinal polarised beams at a
centre of mass energy of the order of 0.5 TeV with a luminosity of about L =
10^34 cm^-2 sec^-1.

</DOC>
<DOC>
<DOCNO> 71326 </DOCNO>
Regularization-independent studies of nonperturbative field theory


  We propose a regularization-independent method for studying a renormalizable
field theory nonperturbatively through its Dyson-Schwinger equations. Using
QED_4 as an example, we show how the coupled equations determining the
nonperturbative fermion and photon propagators can be written entirely in terms
of renormalized quantities, which renders the equations manifestly finite in a
regularization-independent manner. As an illustration of the technique, we
apply it to a study of the fermion propagator in quenched QED_4 with the
Curtis-Pennington electron-photon vertex. At large momenta the mass function,
and hence the anomalous mass dimension gamma_m(alpha), is calculated
analytically and we find excellent agreement with previous work. Finally, we
show that for the CP vertex the perturbation expansion of gamma_m(alpha) has a
finite radius of convergence.

</DOC>
<DOC>
<DOCNO> 12424 </DOCNO>
Large transconductance oscillations in a single-well vertical


  Aharonov-Bohm (AB) interference is reported for the first time in the
conductance of a vertical nanostructure based on a single GaAs/AlGaAs quantum
well (QW). The two lowest subbands of the well are spatially separated by the
Hartree barrier originating from electronic repulsion in the modulation-doped
QW and provide AB two-path geometry. Split-gates control the in-plane
electronic momentum dispersion. In our system, we have clearly demonstrated AB
interference in both electrostatic and magnetic modes. In the latter case the
magnetic field was applied parallel to the QW plane, and perpendicular to the
0.02 um^2 AB loop. In the electrostatic mode of operation the single-QW scheme
adopted led to large transconductance oscillations with relative amplitudes
exceeding 30 %. The relevance of the present design strategy for the
implementation of coherent nanoelectronic devices is underlined.

</DOC>
<DOC>
<DOCNO> 151923 </DOCNO>
Extended superconformal symmetry and Calogero-Marchioro model


  We show that the two dimensional Calogero-Marchioro Model (CMM) without the
harmonic confinement can naturally be embedded into an extended SU(1,1|2)
superconformal Hamiltonian. We study the quantum evolution of the
superconformal Hamiltonian in terms of suitable compact operators of the N=2
extended de Sitter superalgebra with central charge and discuss the pattern of
supersymmetry breaking. We also study the arbitrary D dimensional CMM having
dynamical OSp(2|2) supersymmetry and point out the relevance of this model in
the context of the low energy effective action of the dimensionally reduced
Yang-Mills theory.

</DOC>
<DOC>
<DOCNO> 69578 </DOCNO>
Development of the electroweak phase transition and baryogenesis


  We investigate the evolution of the electroweak phase transition, using a
one-Higgs effective potential that can be regarded as an approximation for the
Minimal Supersymmetric Standard Model. The phase transition occurs in a small
interval around a temperature T_t below the critical one. We calculate this
temperature as a function of the parameters of the potential and of a damping
coefficient related to the viscosity of the plasma. The parameters that are
relevant for baryogenesis, such as the velocity and thickness of the walls of
bubbles and the value of the Higgs field inside them, change significantly in
the range of temperatures where the first-order phase transition can occur.
However, we find that in the likely interval for T_t there is no significant
variation of these parameters. Furthermore, the temperature T_t is in general
not far below the temperature at which bubbles begin to nucleate.

</DOC>
<DOC>
<DOCNO> 67931 </DOCNO>
Determining the CP violating phase $\gamma$


  We review several methods for determining the Kobayashi-Maskawa phase
$\gamma={\rm Arg} V^*_{ub}$ from rate and CP asymmetry measurements in hadronic
B decays. We focus on the processes $B\to DK, B_s\to D_s K$, and on charmless
decays to two light pseudoscalars and decays to a pair of a pseudoscalar and a
vector meson. Theoretical uncertainties underlying these methods are discussed.

</DOC>
<DOC>
<DOCNO> 67946 </DOCNO>
Non-abelian discrete gauge symmetries and inflation


  Obtaining a potential flat enough to provide slow roll inflation is often
difficult when gravitational effects are included. Non-abelian discrete gauge
symmetries can guarantee the flatness of the inflaton potential in this case,
and also provide special field values where inflation can end.

</DOC>
<DOC>
<DOCNO> 101813 </DOCNO>
On C*-algebras Associated with Sofic Shifts


  We show that for a sofic shift Lambda, Matsumoto's C*-algebra O_Lambda is
isomorphic to the Cuntz-Krieger algebra of the left Krieger cover graph of
Lambda.

</DOC>
<DOC>
<DOCNO> 170448 </DOCNO>
Quantum lower bound for sorting


  We prove that \Omega(n log(n)) comparisons are necessary for any quantum
algorithm that sorts n numbers with high success probability and uses only
comparisons. If no error is allowed, at least 0.110nlog_2(n) - 0.067n + O(1)
comparisons must be made. The previous known lower bound is \Omega(n).

</DOC>
<DOC>
<DOCNO> 122455 </DOCNO>
The Nature of Jets: Evidence from Circular Polarization Observations


  We review recent observations of circularly polarized radiation from AGN made
with the VLBA and with the ATCA. We also discuss briefly the detections of the
Galactic sources Sag A* and SS433. The origin of the circular polarization is
still an open question in most cases, and we discuss four possible mechanisms.
Detectable circular polarization is a common property of quasars, but not of
radio galaxies, and is always associated with the compact core. There is
growing evidence that the sign of the circular polarization stays the same over
at least two or three decades in time, suggesting it is a fundamental property
of the jet.

</DOC>
<DOC>
<DOCNO> 170581 </DOCNO>
Coherent quantum measurement for the direct determination of the degree


  An example of a coherent measurement for the direct evaluation of the degree
of polarization of a single-mode optical beam is presented. It is applied to
the case of great practical importance where depolarization is caused by
polarization mode dispersion. It is demonstrated that coherent measurement has
the potential of significantly increasing the information gain, compared to
standard incoherent measurements.

</DOC>
<DOC>
<DOCNO> 178993 </DOCNO>
Probing the nuclear equation of state by $K^+$ production in heavy ion


  The dependence of $K^+$ production on the nuclear equation of state is
investigated in heavy ion collisions. An increase of the excitation function of
$K^+$ multiplicities obtained in heavy ($Au+Au$) over light ($C+C$) systems
when going far below threshold which has been observed by the KaoS
Collaboration strongly favours a soft equation of state. This observation holds
despite of the influence of an in-medium kaon potential predicted by effective
chiral models which is necessary to reproduce the experimental $K^+$ yields.

</DOC>
<DOC>
<DOCNO> 151350 </DOCNO>
Meaning of Noncommutative Geometry and the Planck-Scale Quantum Group


  This is an introduction for nonspecialists to the noncommutative geometric
approach to Planck scale physics coming out of quantum groups. The canonical
role of the `Planck scale quantum group' $C[x]\bicross C[p]$ and its
observable-state T-duality-like properties are explained. The general meaning
of noncommutativity of position space as potentially a new force in Nature is
explained as equivalent under quantum group Fourier transform to curvature in
momentum space. More general quantum groups $C(G^\star)\bicross U(g)$ and
$U_q(g)$ are also discussed. Finally, the generalisation from quantum groups to
general quantum Riemannian geometry is outlined. The semiclassical limit of the
latter is a theory with generalised non-symmetric metric $g_{\mu\nu}$ obeying
$\nabla_\mu g_{\nu\rho}-\nabla_\nu g_{\mu\rho}=0$

</DOC>
<DOC>
<DOCNO> 150601 </DOCNO>
Superstrings, Gauge Fields and Black Holes


  There has been spectacular progress in the development of string and
superstring theories since its inception thirty years ago. Development in this
area has never been impeded by the lack of experimental confirmation. Indeed,
numerous bold and imaginative strides have been taken and the sheer elegance
and logical consistency of the arguments have served as a primary motivation
for string theorists to push their formulations ahead. In fact the development
in this area has been so rapid that new ideas quickly become obsolete. On the
other hand, this rapid development has proved to be the greatest hindrance for
novices interested in this area. These notes serve as a gentle introduction to
this topic. In these elementary notes, we briefly review the RNS formulation of
superstring theory, GSO projection, $D$-branes, bosonic strings, dualities,
dynamics of $D$-branes and the microscopic description of Bekenstein entropy of
a black hole.

</DOC>
<DOC>
<DOCNO> 84281 </DOCNO>
Symmetries of asymptotically flat axisymmetric spacetimes with null dust


  Symmetries of spacetimes with null dust field as a source compatible with
asymptotic flatness are studied by using the Bondi-Sachs-van der Burg
formalism. It is shown that in an axially symmetric spacetime with null dust
field in which at least locally a smooth null infinity in the sense of Penrose
exists, the only allowable additional Killing vector forming with the axial one
a two-dimensional Lie algebra (the axial and the additional Killing vector are
not assumed to be hypersurface orthogonal) is a supertranslational Killing
vector and the gravitational field is then non-radiative (the Weyl tensor has a
non-radiative character).

</DOC>
<DOC>
<DOCNO> 14077 </DOCNO>
Random Dirac Fermions: The su(N) Gauge Potential and Z_N Twists


  We obtain the disorder averaged (critical) four-point correlation functions
for N species of (two-dimensional Euclidean) Dirac fermions subject to a
(Gaussian) random su(N) gauge field. The replica approach and the strong
disorder approach yield identical results, as one might expect in the light of
recent developments in the N=2 case [1]. We establish a connection with
`dressed' Z_N twist fields in the c=-2 logarithmic conformal field theory
(LCFT), thereby extending the recent connection to `dressed' Z_2 twists [1,2].
We draw attention to the fact that `dressed' Z_2 twist operators have
previously appeared in the description of half flux-quantum quasiholes in the
bulk excitations of the Haldane--Rezayi Quantum Hall state [3].

</DOC>
<DOC>
<DOCNO> 10703 </DOCNO>
Theory for Decoupling in High-T_c Superconductors from an Analysis of


  The nature of decoupling in the mixed phase of extremely type-II layered
superconductors is studied theoretically through a duality transformation of
the layered XY model with frustration. In the limit of weak coupling, we
generally find that the Josephson effect is absent if and only if the phase
correlations within isolated layers are short range. In the case specific to
uniform frustration, we notably identify a decoupled pancake vortex liquid
phase that is bounded by first-order and second-order decoupling lines in the
magnetic field vs. temperature plane. These transitions potentially account for
the flux-lattice melting and for the flux-lattice depinning that is observed in
clean high-temperature superconductors.

</DOC>
<DOC>
<DOCNO> 118558 </DOCNO>
A Measurement of the Cosmic Ray Spectrum and Composition at the Knee


  The energy spectrum and primary composition of cosmic rays with energy
between $3\times 10^{14}$ and $3\times10^{16}\unit{eV}$ have been studied using
the CASA-BLANCA detector. CASA measured the charged particle distribution of
air showers, while BLANCA measured the lateral distribution of Cherenkov light.
The data are interpreted using the predictions of the CORSIKA air shower
simulation coupled with four different hadronic interaction codes.
  The differential flux of cosmic rays measured by BLANCA exhibits a knee in
the range of 2--3 PeV with a width of approximately 0.5 decades in primary
energy. The power law indices of the differential flux below and above the knee
are $-2.72\pm0.02$ and $ -2.95\pm0.02$.
  We present our data both as a mean depth of shower maximum and as a mean
nuclear mass. A multi-component fit using four elemental species shows the same
composition trends given by the mean quantities, and also indicates that QGSJET
and VENUS are the preferred hadronic interaction models. We find that an
initially mixed composition turns lighter between 1 and 3 PeV, and then becomes
heavier with increasing energy above 3 PeV.

</DOC>
<DOC>
<DOCNO> 122858 </DOCNO>
Precise Masses for Wolf 1062 AB from Hubble Space Telescope


  We present an analysis of astrometric data from FGS 3, a white-light
interferometer on {\it HST}, and of radial velocity data from two ground-based
campaigns. We model the astrometric and radial velocity measurements
simultaneously to obtain parallax, proper motion and component masses for Wolf
1062 = Gl 748 AB (M3.5V). To derive the mass fraction, we relate FGS 3 fringe
scanning observations of the science target to a reference frame provided by
fringe tracking observations of a surrounding star field. We obtain an absolute
parallax $\pi_{abs} = 98.0 \pm 0.4$ milliseconds of arc, yielding ${\cal M}_A =
0.379 \pm 0.005{\cal M}_{\sun}$ and ${\cal M}_B= 0.192 \pm 0.003 {\cal
M}_{\sun}$, high quality component masses with errors of only 1.5%.

</DOC>
<DOC>
<DOCNO> 121429 </DOCNO>
Mass estimates in short-period compact binaries


  Using stellar models we investigate the relation between mass and the
spectral type of the secondary star in low-mass short-period compact binaries
such as cataclysmic variables and soft X-ray transients. Allowing for different
mass transfer rates and different system ages prior to mass transfer we find
that the secondaries should populate a band in the spectral type vs. mass
plane. The mass M_ms of a ZAMS star with the same spectral type as the donor is
effectively an upper limit to the donor mass. The lower mass limit for a given
spectral type depends on the mixing length parameter. If this is large, there
is no lower limit if the spectral type is later than K6. The band width
decreases from 0.4 M_sun at K6 to less than 0.2 M_sun at K0. If the mixing
length parameter is small, there is no lower mass limit if the spectral type is
later than M2, and the band width decreases from 0.2 M_sun at M2 to less than
0.1 M_sun for types earlier than K0. We also point out an error in the method
suggested by Beekman et al. (1997) to estimate the primary mass in a soft X-ray
transient.

</DOC>
<DOC>
<DOCNO> 99480 </DOCNO>
Multiparticle SUSY quantum mechanics and the representations of


  The method of multidimensional SUSY Quantum Mechanics is applied to the
investigation of supersymmetrical N-particle systems on a line for the case of
separable center-of-mass motion. New decompositions of the superhamiltonian
into block-diagonal form with elementary matrix components are constructed.
Matrices of coefficients of these minimal blocks are shown to coincide with
matrices of irreducible representations of permutations group S_N, which
correspond to the Young tableaux (N-M,1^M). The connections with known
generalizations of N-particle Calogero and Sutherland models are established.

</DOC>
<DOC>
<DOCNO> 178975 </DOCNO>
Strange Dibaryons in Neutron Stars and in Heavy-Ion Collisions


  The formation of dibaryons with strangeness are discussed for the interior of
neutron stars and for central relativistic heavy-ion collisions. We derive
limits for the properties of H-dibaryons from pulsar data. Signals for the
formation of possible bound states with hyperons at BNL's Relativistic
Heavy-Ion Collider (RHIC) are investigated by studying their weak decay
patterns and production rates.

</DOC>
<DOC>
<DOCNO> 13657 </DOCNO>
Universal eigenvector statistics in a quantum scattering ensemble


  We calculate eigenvector statistics in an ensemble of non-Hermitian matrices
describing open quantum systems [F. Haake et al., Z. Phys. B 88, 359 (1992)] in
the limit of large matrix size. We show that ensemble-averaged eigenvector
correlations corresponding to eigenvalues in the center of the support of the
density of states in the complex plane are described by an expression recently
derived for Ginibre's ensemble of random non-Hermitian matrices.

</DOC>
<DOC>
<DOCNO> 122126 </DOCNO>
Near-infrared Imaging and [O~I] spectroscopy of IC 443 using 2MASS and


  We present near-infrared J (1.25um), H (1.65um), and Ks (2.17um) imaging of
the entire supernova remnant IC 443 from the Two Micron All Sky Survey (2MASS),
and Infrared Space Observatory (ISO) LWS observations of [O I]. Near-infrared
emission from IC 443 was detected in all three bands from most of the optically
bright parts of the remnant, revealing a shell-like morphology, with bright Ks
band emission along the southern ridge and bright J and H along the
northeastern rim. The color and morphological structure are very different
between the northeastern and southern parts. J and H band emission from the
northeast rim is comparably bright and can be explained mostly by [Fe~II] line
emission. The southern ridge is dominated by Ks band light exhibiting a clumped
and knotty structure. Molecular hydrogen lines can explain most of K$_s$ band
and at least half of J and H band emission in the south. Hence, the prominent
broad-band color differences arise from physically different mechanisms: atomic
fine structure lines along the northeastern rim and molecular ro-vibrational
lines along the southern ridge. Shock models imply a fast J-shock with vs~100
km/s and 10<n<10^3 cm^-3 for the northeastern rim and a slow C-shock with vs
\~30 km/s and n~10^{4} cm^{-3} for the southern ridge, respectively.

</DOC>
<DOC>
<DOCNO> 151429 </DOCNO>
A Note on (D(p-2),Dp) Bound State and Noncommutative Yang-Mills Theory


  We give a microscopic explanation for the recently observed equivalence among
thermodynamics of supergravity solutions for Dp-branes with or without NS
B-field and for D(p-2)-branes with vanishing B-field and two delocalized
transverse directions by showing that these D-brane configurations are related
to one another through T-duality transformations. This result also gives an
evidence for the equivalence among the noncommutative and the ordinary
Yang-Mills theories corresponding to the decoupling limits of the worldvolume
theories of such D-brane configurations.

</DOC>
<DOC>
<DOCNO> 151306 </DOCNO>
Rotation Symmetry Breaking Condensate in a Scalar Theory


  Motivated by an analogy with the conformal factor problem in gravitational
theories of the $R+R^2$-type we investigate a $d$-dimensional Euclidean field
theory containing a complex scalar field with a quartic self interaction and
with a nonstandard inverse propagator of the form $-p^2+p^4$. Nonconstant
spin-wave configurations minimize the classical action and spontaneously break
the rotation symmetry to a lower-dimensional one. In classical statistical
physics this corresponds to a spontaneous formation of layers. Within the
effective average action approach we determine the renormalization group flow
of the dressed inverse propagator and of a family of generalized effective
potentials for nonzero-momentum modes. Already in the leading order of the
semiclassical expansion we find strong ``instability induced'' renormalization
effects which are due to the fact that the naive vacuum (vanishing field) is
unstable towards the condensation of modes with a nonzero momentum. We argue
that the (quantum) ground state of our scalar model indeed leads to spontaneous
breaking of rotation symmetry.

</DOC>
<DOC>
<DOCNO> 170075 </DOCNO>
A Simple Algorithm for Local Conversion of Pure States


  We describe an algorithm for converting one bipartite quantum state into
another using only local operations and classical communication, which is much
simpler than the original algorithm given by Nielsen [Phys. Rev. Lett. 83, 436
(1999)]. Our algorithm uses only a single measurement by one of the parties,
followed by local unitary operations which are permutations in the local
Schmidt bases.

</DOC>
<DOC>
<DOCNO> 169954 </DOCNO>
Contact between laboratory instruments and equations of quantum


  Ambiguity in the contact between laboratory instruments and equations of
quantum mechanics is formulated in terms of responses of the instruments to
commands transmitted to them by a Classical digital Process-control Computer
(CPC); in this way instruments are distinguished from quantum-mechanical models
(sets of equations) that specify what is desired of the instruments. Results
include: (1) a formulation of quantum mechanics adapted to computer-controlled
instruments; (2) a lower bound on the precision of unitary transforms required
for quantum searching and a lower bound on sample size needed to show that
instruments implement a desired model at that precision; (3) a lower bound on
precision of timing required of a CPC in directing instruments; (4) a
demonstration that guesswork is necessary in ratcheting up the precision of
commands.

</DOC>
<DOC>
<DOCNO> 169929 </DOCNO>
"Velocities" in Quantum Mechanics


  The present paper deals with some kind of quantum ``velocity'' which is
introduced by the method of hydrodynamical analogy. It is found that this
``velocity'' is in general irrotational, namely, a vorticity vanishes, and then
a velocity potential must exist in quantum mechanics. In some elementary
examples of stable systems we will see what the ``velocities'' are. In
particular, the two-dimensional flows of these examples can be expressed by
complex velocity potentials whose real and imaginary parts are the velocity
potentials and stream functions, respectively.

</DOC>
<DOC>
<DOCNO> 84866 </DOCNO>
Combinatorial quantisation of Euclidean gravity in three dimensions


  In the Chern-Simons formulation of Einstein gravity in 2+1 dimensions the
phase space of gravity is the moduli space of flat G-connections, where G is a
typically non-compact Lie group which depends on the signature of space-time
and the cosmological constant. For Euclidean signature and vanishing
cosmological constant, G is the three-dimensional Euclidean group. For this
case the Poisson structure of the moduli space is given explicitly in terms of
a classical r-matrix. It is shown that the quantum R-matrix of the quantum
double D(SU(2)) provides a quantisation of that Poisson structure.

</DOC>
<DOC>
<DOCNO> 150397 </DOCNO>
Algebraic Quantum Field Theory, Perturbation Theory, and the Loop


  The perturbative treatment of quantum field theory is formulated within the
framework of algebraic quantum field theory. We show that the algebra of
interacting fields is additive, i.e. fully determined by its subalgebras
associated to arbitrary small subregions of Minkowski space. We also give an
algebraic formulation of the loop expansion by introducing a projective system
${\cal A}^{(n)}$ of observables ``up to $n$ loops'' where ${\cal A}^{(0)}$ is
the Poisson algebra of the classical field theory. Finally we give a local
algebraic formulation for two cases of the quantum action principle and compare
it with the usual formulation in terms of Green's functions.

</DOC>
<DOC>
<DOCNO> 85552 </DOCNO>
Covariant Geometric Prequantization of Fields


  A geometric prequantization formula for the Poisson-Gerstenhaber bracket of
forms found within the DeDonder-Weyl Hamiltonian formalism earlier is
presented. The related aspects of covariant geometric quantization of field
theories are sketched. In particular, the importance of the framework of
Clifford and spinor bundles and superconnections in this context is underlined.

</DOC>
<DOC>
<DOCNO> 13200 </DOCNO>
Transfer Matrices and Partition-Function Zeros for Antiferromagnetic


  We study the chromatic polynomials for m \times n square-lattice strips, of
width 9 <= m <= 13 (with periodic boundary conditions) and arbitrary length n
(with free boundary conditions). We have used a transfer matrix approach that
allowed us also to extract the limiting curves when n \to \infty. In this limit
we have also obtained the isolated limiting points for these square-lattice
strips and checked some conjectures related to the Beraha numbers.

</DOC>
<DOC>
<DOCNO> 84960 </DOCNO>
The Earliest Phase Transition?


  The question of a phase transition in exiting the Planck epoch of the early
universe is addressed. An order parameter is proposed to help decide the issue,
and estimates are made concerning its behavior. Our analysis is suggestive that
a phase transition occurred.

</DOC>
<DOC>
<DOCNO> 11519 </DOCNO>
Kinetic Friction due to Ohm's Law Heating


  Using both a recent calculation by Bruch of the damping of the motion of a
monolayer nitrogen film oscillating harmonically on a metallic surface due to
Ohm's law heating and a Thomas-Fermi approximation treatment of the Ohm's law
heating mechanism, which accounts for the nonzero thickness of the surface
region of a metal, it is argued that this mechanism for friction is able to
account for recent measurements of the drop in the friction for anitrogen film
sliding over a lead substrate as it goes below its superconducting transition
temperature. Bruch's calculation is also made more transparent by re-doing the
calculation for a film sliding at constant speed, instead of oscillating. Using
this treatment, it is easily shown that Bruch's calculation is equivalent to
integrating Boyer's solution of the problem of a charge sliding over a metallic
surface over the charge density of the monolayer nitrogen film.

</DOC>
<DOC>
<DOCNO> 102658 </DOCNO>
On the valuation of arithmetic-average Asian options: Laguerre series


  In a recent significant advance, using Laguerre series, the valuation of
Asian options has been reduced by Dufresne to computing the negative moments of
Yor's accumulation processes. For these he has given functional recursion rules
whose probabilistic structure has been the object of intensive recent studies
of Yor and co-workers. Stressing the role of Theta functions, this paper now
solves these recursion rules and expresses these negative moments as linear
combinations of certain Theta integrals. Using the Jacobi transformation
formula, very rapidly and very stably convergent series for them are derived.
In this way computable series for Black--Scholes price of the Asian option
result which are numerically illustrated. Moreover, the Laguerre series
approach of Dufresne is made rigorous, and extensions and modifications are
discussed. The key for this is the analysis of the integrability and growth
properties of Yor's 1992 Asia density, basic problems which seem to be
addressed here for the first time.

</DOC>
<DOC>
<DOCNO> 101472 </DOCNO>
Explicit isoperimetric constants and phase transitions in the


  The random-cluster model is a dependent percolation model that has
applications in the study of Ising and Potts models. In this paper, several new
results are obtained for the random-cluster model on nonamenable graphs with
cluster parameter $q\geq 1$. Among these, the main ones are the absence of
percolation for the free random-cluster measure at the critical value, and
examples of planar regular graphs with regular dual where $\pc^\f (q) > \pu^\w
(q)$ for $q$ large enough. The latter follows from considerations of
isoperimetric constants, and we give the first nontrivial explicit calculations
of such constants. Such considerations are also used to prove non-robust phase
transition for the Potts model on nonamenable regular graphs.

</DOC>
<DOC>
<DOCNO> 116333 </DOCNO>
A Connection between Gravitation and Electromagnetism


  It is argued that there is a connection between the fundamental forces of
electromagnetism and gravitation. This connection occurs because of: 1) the
fundamental significance of the finite and invariant velocity of light in
inertial reference frames in the special theory, and 2) the reliance of the
general theory of relativity upon the special theory of relativity locally in
spacetime. The connection between the fundamental forces of electromagnetism
and gravitation follows immediately from these two points. A brief review is
provided of: 1) the role of the finite and invariant velocity of light in
inertial reference frames in the special theory, and 2) certain fundamental
concepts of the general theory, including its reliance on the special theory
locally.

</DOC>
<DOC>
<DOCNO> 117965 </DOCNO>
Gravitational Lenses With More Than Four Images: I. Classification of


  We study the problem of gravitational lensing by an isothermal elliptical
density galaxy in the presence of a tidal perturbation. When the perturbation
is fairly strong and oriented near the galaxy's minor axis, the lens can
produce image configurations with six or even eight highly magnified images
lying approximately on a circle. We classify the caustic structures in the
model and identify the range of models that can produce such lenses. Sextuple
and octuple lenses are likely to be rare because they require special lens
configurations, but a full calculation of the likelihood will have to include
both the existence of lenses with multiple lens galaxies and the strong
magnification bias that affects sextuple and octuple lenses. At optical
wavelengths these lenses would probably appear as partial or complete Einstein
rings, but at radio wavelengths the individual images could probably be
resolved.

</DOC>
<DOC>
<DOCNO> 121968 </DOCNO>
Self-Gravitating N-Body Systems out of Equilibrium


  Real physical systems are often maintained off equilibrium by energy or
matter flows. If these systems are far from equilibrium then the
thermodynamical branch become unstable and fluctuations can lead them to other
more stable states. These new states are often endowed with higher degrees of
organization. In order to explore whether an energy-flow in combination with
self-gravity can lead to complex, inhomogeneous structures, like observed in
the interstellar medium (ISM), we perform N-body simulations of
self-gravitating systems subjected to an energy-flow. Moreover we perform some
simple gravo-thermal N-body experiments and compare them with theoretical
results. We find negative specific heat in an energy range as predicted by
Follana & Laliena (1999).

</DOC>
<DOC>
<DOCNO> 150723 </DOCNO>
Brane Universe and Multigravity: Modification of gravity at large and


  We consider a modification of gravity at large distances in a Brane Universe
which was discussed recently. In these models the modification of gravity at
large distances is ultimately connected to existence of negative tension
brane(s) and exponentially small tunneling factor. We discuss a general model
which interpolates between Bi-gravity model and GRS model. We also discuss the
possible mechanism of stabilization for negative tension branes in AdS
background. Finally we show that extra degrees of freedom of massive gravitons
do not lead to disastrous contradiction with General Relativity if the
stabilization condition $\int dy \sqrt{-G^{(5)}} (T^\mu_\mu-2T^5_5)=0$ is
implemented.

</DOC>
<DOC>
<DOCNO> 121815 </DOCNO>
Discovery of a redshifted Iron K-line in the X-ray afterglow of GRB


  We report the detection (3 sigma significance level) of a strong iron
emission line in the X-ray spectrum of the afterglow of GRB 000214
(``Valentine's Day Burst'') observed by BeppoSAX. An emission line feature was
observed with a centroid energy of 4.7+/-0.2 keV which, if interpreted as
K-alpha emission from hydrogen-like iron, corresponds to a redshift of z=0.47.
The observed intensity (EW ~2 keV) and duration (tens of hours) of the line
give information on the distance, from the burst region, of the emitting
material (R>3x10^15 cm) and its mass (M>1.4 solar mass). These results are not
easily reconciled with the binary merger and hypernova models for gamma ray
bursts.

</DOC>
<DOC>
<DOCNO> 11080 </DOCNO>
T=0 Partition Functions for Potts Antiferromagnets on Lattice Strips


  We present exact calculations of the zero-temperature partition function for
the $q$-state Potts antiferromagnet (equivalently, the chromatic polynomial)
for families of arbitrarily long strip graphs of the square and triangular
lattices with width $L_y=4$ and boundary conditions that are doubly periodic or
doubly periodic with reversed orientation (i.e. of torus or Klein bottle type).
These boundary conditions have the advantage of removing edge effects. In the
limit of infinite length, we calculate the exponent of the entropy, $W(q)$ and
determine the continuous locus ${\cal B}$ where it is singular. We also give
results for toroidal strips involving ``crossing subgraphs''; these make
possible a unified treatment of torus and Klein bottle boundary conditions and
enable us to prove that for a given strip, the locus ${\cal B}$ is the same for
these boundary conditions.

</DOC>
<DOC>
<DOCNO> 116487 </DOCNO>
CTMC calculations of electron capture and ionization in collisions of


  We have performed classical trajectory Monte Carlo (CTMC) studies of electron
capture and ionization in multiply charged (Q=8) ion-Rydberg atom collisions at
intermediate impact velocities. Impact parallel to the minor and to the major
axis, respectively, of the initial Kepler electron ellipse has been
investigated. The important role of the initial electron momentum distribution
found for singly charged ion impact is strongly disminished for higher
projectile charge, while the initial spatial distribution remains important for
all values of Q studied.

</DOC>
<DOC>
<DOCNO> 170703 </DOCNO>
Optimal estimation of quantum dynamics


  We construct the optimal strategy for the estimation of an unknown unitary
transformation $U\in SU(d)$. This includes, in addition to a convenient
measurement on a probe system, finding which is the best initial state on which
$U$ is to act. When $U\in SU(2)$, such an optimal strategy can be applied to
estimate simultaneously both the direction and the strength of a magnetic
field, and shows how to use a spin 1/2 particle to transmit information about a
whole coordinate system instead of only a direction in space.

</DOC>
<DOC>
<DOCNO> 68105 </DOCNO>
Heavy quark production as sensitive test for an improved description of


  QCD dynamics at small quark and gluon momentum fractions or large total
energy, which plays a major role for HERA, the Tevatron, RHIC and LHC physics,
is still poorly understood. For one of the simplest processes, namely
bottom-antibottom production, next-to-leading-order perturbation theory fails.
We show that the combination of two recently developed theoretical concepts,
the k_perp-factorization and the next-to-leading-logarithmic-approximation BFKL
vertex, gives perfect agreement with data. One can therefore hope that these
concepts provide a valuable foundation for the description of other high energy
processes.

</DOC>
<DOC>
<DOCNO> 121963 </DOCNO>
Emission Mechanisms in X-Ray Faint Galaxies


  Hot gas dominates the emission in X-ray luminous early-type galaxies, but in
relatively X-ray faint systems, integrated X-ray emission from discrete
stellar-like sources is thought to be considerable, although the amount of the
contribution is controversial. To help resolve this issue, we examine the
radial X-ray surface brightness distribution of 17 X-ray faint galaxies
observed with the ROSAT HRI and PSPC. We assume that the stellar contribution
follows a de Vaucouleurs law while the hot gas component follows a King beta
model. For some galaxies, both models fit equally well, but for a number of
systems, a dual component model yields the best fit, from which upper bounds
are placed on the stellar contribution. Best-fit values for the stellar
contribution are inconsistent with (lower than) that suggested by Fabbiano,
Gioia, & Trinchieri (1989) and estimated from the bulge of M31, but are
consistent with the Forman, Jones, & Tucker (1985) estimate of the stellar
fraction in X-ray faint elliptical and S0 galaxies. Our results indicate an
upper limit to discrete sources of L_X/L_B = 1.6 x 10^29 ergs/s/L(solar).

</DOC>
<DOC>
<DOCNO> 170641 </DOCNO>
Symmetries and solutions of the three-dimensional Paul trap


  Using the symmetries of the three-dimensional Paul trap, we derive the
solutions of the time-dependent Schr\"odinger equation for this system, in both
Cartesian and cylindrical coordinates. Our symmetry calculations provide
insights that are not always obvious from the conventional viewpoint.

</DOC>
<DOC>
<DOCNO> 169609 </DOCNO>
The Physical Model of Schrodinger Electron. Schrodinger Convenient Way


  The physical model (PhsMdl) of a Schrodinger nonrelativistic quantized
electron (ShEl) is built by means of a transition of the quadratic differential
particle equation of Hamilton-Jacoby into the quadratic differential wave
equation of Schrodinger in this work, which interprets the physical reason of
its quantum (wave and stochastic) behaviour by explanation of the physical
reason, which forces the classical Lorentz electron (LrEl) to participate in
Furthian quantized stochastic oscillation motion, which turn it into quantum
ShEl. It is performed that this transition is realized by my consideration the
Bohm's quantum potential as a kinetic energy of the forced Furthian quantized
stochastic oscillation motion of the ShEl's well spread elementary electric
charge close to a smooth thin trajectory of a classical LrEl. There exist as an
essential analogy between the Furthian quantum stochastic trembling oscillation
motion and the Brownian classical stochastic trembling motion so and between
the description of their behaviours.

</DOC>
<DOC>
<DOCNO> 69298 </DOCNO>
A See-Saw Mechanism for Large Neutrino Mixing from Small Quark and


  I introduce and sketch the main features of those see-saw models where a
large atmospheric mixing can be achieved starting from nearly diagonal matrices
for charged leptons, Dirac neutrinos and Majorana right-handed neutrinos. It
turns out that these models can be realized in Grand Unified Theories and they
are well compatible with the related phenomenology of fermion masses and
mixings.

</DOC>
<DOC>
<DOCNO> 151136 </DOCNO>
Open String on Symmetric Product


  We develop some basic properties of the open string on the symmetric product
which is supposed to describe the open string field theory in discrete
lightcone quantization (DLCQ). After preparing the consistency conditions of
the twisted boundary conditions for Annulus/M\"obius/Klein Bottle amplitudes in
generic non-abelian orbifold, we classify the most general solutions of the
constraints when the discrete group is $S_N$. We calculate the corresponding
orbifold amplitudes from two viewpoints -- from the boundary state formalism
and from the trace over the open string Hilbert space. It is shown that the
topology of the world sheet for the short string and that of the long string in
general do not coincide. For example the annulus sector for the short string
contains all the sectors (torus, annulus, Klein bottle, M\"obius strip) of the
long strings. The boundary/cross-cap states of the short strings are classified
into three categories in terms of the long string, the ordinary boundary and
the cross-cap states, and the ``joint'' state which describes the connection of
two short strings. We show that the sum of the all possible boundary conditions
is equal to the exponential of the sum of the irreducible amplitude -- one body
amplitude of long open (closed) strings. This is typical structure of DLCQ
partition function. We examined that the tadpole cancellation condition in our
language and derived the well-known gauge group $SO(2^{13})$.

</DOC>
<DOC>
<DOCNO> 67994 </DOCNO>
Status of the MSW Solutions to the Solar Neutrino Problem


  In this talk we present the results of an updated global analysis of
two-flavor MSW solutions to the solar neutrino problem in terms of conversions
of $\nu_e$ into active or sterile neutrinos including the the full data set
corresponding to the 825-day Super-Kamiokande data sample as well as to
Chlorine, GALLEX and SAGE experiments.

</DOC>
<DOC>
<DOCNO> 67963 </DOCNO>
Locally Anisotropic Black Holes in Einstein Gravity


  By applying the method of moving frames modelling one and two dimensional
local anisotropies we construct new solutions of Einstein equations on
pseudo-Riemannian spacetimes. The first class of solutions describes
non-trivial deformations of static spherically symmetric black holes to
locally anisotropic ones which have elliptic (in three dimensions) and
ellipsoidal, toroidal and elliptic and another forms of cylinder symmetries (in
four dimensions). The second class consists from black holes with oscillating
elliptic horizons.

</DOC>
<DOC>
<DOCNO> 178533 </DOCNO>
Nonaxial octupole deformations in light N=Z nuclei at high spins


  High spin states of ^{32}S$ and ^{56}Ni are investigated by means of the
cranking Hartree-Fock method with the Gogny interaction without imposing a
restriction on the axial reflection symmetry. It was found that a non-axial
octupole deformation of the Y_{31} type becomes important in the yrast states
of ^{32}S. A similar effect is predicted for the nucleus ^{56}Ni.

</DOC>
<DOC>
<DOCNO> 101719 </DOCNO>
Towards a 2-dimensional notion of holonomy


  Previous work (Pradines, 1966, Aof and Brown, 1992) has given a setting for a
holonomy Lie groupoid of a locally Lie groupoid. Here we develop analogous
2-dimensional notions starting from a locally Lie crossed module of groupoids.
This involves replacing the Ehresmann notion of a local smooth coadmissible
section of a groupoid by a local smooth coadmissible homotopy (or free
derivation) for the crossed module case. The development also has to use
corresponding notions for certain types of double groupoids. This leads to a
holonomy Lie groupoid rather than double groupoid, but one which involves the
2-dimensional information.

</DOC>
<DOC>
<DOCNO> 85105 </DOCNO>
The Shortest Scale of Quantum Field Theory


  The vacuum of quantum field theories of a large number of fields can be
unstable due to strong vacuum energy fluctuations, decaying rapidly into many
small black holes. We propose that in stable theories, the number of
independent quantum mechanical degrees of freedom in a given volume is
therefore bounded. Our bound can be made consistent with entropy bounds and
holography, but does not seem to be equivalent to either. Rather than setting a
direct limit on the number of elementary particles it prescribes a definition,
in terms of the Planck length and the number of species, of the shortest scale
of any quantum field theory compatible with gravity.

</DOC>
<DOC>
<DOCNO> 100456 </DOCNO>
On the space of Fredholm operators


  We describe two topologies on the space of unbounded Fredholm operators and
we explain their K-theoretic relevance. In the process we also prove a very
general result concerning the continuity of families of first order, elliptic
boundary value problems.

</DOC>
<DOC>
<DOCNO> 152411 </DOCNO>
The Cohomological Supercharge


  We discuss the supersymmetry operator in the cohomological formulation of
dimensionally reduced SYM. By establishing the cohomology, a large class of
invariants are classified.

</DOC>
<DOC>
<DOCNO> 178634 </DOCNO>
The Nambu-Jona-Lasinio model of light nuclei


  The Nambu-Jona-Lasinio model of the deuteron suggested by Nambu and
Jona-Lasinio (Phys. Rev. 124 (1961) 246) is formulated from the first
principles of QCD. The deuteron appears as a neutron-proton collective
excitation, i.e. a Cooper np-pair, induced by a phenomenological local
four-nucleon interaction in the nuclear phase of QCD. The model describes the
deuteron coupled to itself, nucleons and other particles through one-nucleon
loop exchanges providing a minimal transfer of nucleon flavours from initial to
final nuclear states and accounting for contributions of nucleon-loop anomalies
which are completely determined by one-nucleon loop diagrams. The dominance of
contributions of nucleon-loop anomalies to effective Lagrangians of low-energy
nuclear interactions is justified in the large N_C expansion, where N_C is the
number of quark colours.

</DOC>
<DOC>
<DOCNO> 116484 </DOCNO>
Theory of acoustic analog of magneto-optic Kerr effect under


  Theory of the acoustic analog of the polar Kerr effect is developed for an
inclined incidence of the p-type wave on the interface between isotropic
non-magnetic medium and ferromagnetic cubic crystal. Magnetic field dependences
of ellipticity and rotation of the polarization plane of the reflected wave
under magnon-phonon resonance are analysed in a weak-coupling approximation for
interaction of magnetic and elastic subsystems.

</DOC>
<DOC>
<DOCNO> 119959 </DOCNO>
Detection of the thermal radio continuum emission from the G9.62+0.19-F


  We present new high resolution and high sensitivity multi-frequency VLA radio
continuum observations of the G9.62+0.19-F hot molecular core. We detect for
the first time faint centimetric radio continuum emission at the position of
the core. The centimetric continuum spectrum of the source is consistent with
thermal emission from ionised gas. This is the first direct evidence that a
newly born massive star is powering the G9.62+0.19-F hot core.

</DOC>
<DOC>
<DOCNO> 10411 </DOCNO>
Collapse of a randomly forced particle: a comment


  We refute the arguments by Anton in cond-mat/0004390, which set out to
disprove the existence of a collapse transition for a randomly forced inelastic
particle.

</DOC>
<DOC>
<DOCNO> 102161 </DOCNO>
Fields, towers of function fields meeting asymptotic bounds, and basis


  In this work, we use the notion of ``symmetry'' of functions for an extension
$K/L$ of finite fields to produce extensions of a function field $F/K$ in which
almost all places of degree one split completely. Then we introduce the notion
of ``quasi-symmetry'' of functions for $K/L$, and demonstrate its use in
producing extensions of $F/K$ in which all places of degree one split
completely. Using these techniques, we are able to restrict the ramification
either to one chosen rational place, or entirely to non-rational places. We
then apply these methods to the related problem of building asymptotically good
towers of function fields. We construct examples of towers of function fields
in which all rational places split completely throughout the tower. We
construct Abelian towers with this property also.
  Furthermore, all of the above are done explicitly, ie., we give generators
for the extensions, and equations that they satisfy.
  We also construct an integral basis for a set of places in a tower of
function fields meeting the Drinfeld-Vladut bound using the discriminant of the
tower localized at each place. Thus we are able to obtain a basis for a
collection of functions that contains the set of regular functions in this
tower. Regular functions are of interest in the theory of error-correcting
codes as they lead to an explicit description of the code associated to the
tower by providing the code's generator matrix.

</DOC>
<DOC>
<DOCNO> 119194 </DOCNO>
Detection of the VLBI-scale Counter Jet in NGC 6251


  Mapping the central 5 pc region of the nearby radio galaxy NGC 6251 with a
0.2 pc resolution using VLBI at two radio frequencies, 5 GHz and 15 GHz, we
have found the sub-pc-scale counter jet for the first time in this radio
galaxy. This discovery allows us to investigate the jet acceleration based on
the relativistic beaming model (Ghisellini et al. 1993).

</DOC>
<DOC>
<DOCNO> 116880 </DOCNO>
The Low Energy Beam Transport System of the New GSI High Current


  The UNILAC was improved for high current performance by replacing the Wideroe
prestripper accelerator by an RFQ and an IH-type DTL. In addition, one of two
ion source terminals was equipped with high current sources of MUCIS- and
MEVVA-type. Therefore, a redesign of the LEBT from the ion source to the RFQ
entrance was necessary. The new LEBT was installed at the beginning of 1999.
The commissioning was carried mainly with a high intense argon beam. The
achieved 17 emA Ar+ are 6 emA above the RFQ design intensity. The expected
performance of the new LEBT was achieved: full transmission for high current
beams, preservation of brilliance along the beam line, isotope separation for
all elements, transverse phase space matching to the RFQ linac, and macropulse
shaping. In particular, the high degree of space charge compensation was
confirmed.

</DOC>
<DOC>
<DOCNO> 101996 </DOCNO>
Diophantine properties of elements of SO(3)


  A number alpha in R is diophantine if it is not well approximable by
rationals, i.e. for some C, nu>0 and any relatively prime p, q in Z we have
|alpha q -p|>C q^{-1-\vu}. It is well-known and easy to prove that almost every
alpha in R is diophantine. In this paper we address a noncommutative version of
the question about diophantine properties. Consider a pair A,B in SO(3) and for
each n in Z_+ take all possible words in A, A^{-1}, B, and B^{-1} of length n,
i.e. for a multiindex I=(i_1,j_1,..., i_s,j_s) put |I|=\sum_{k=1}^s
(|i_k|+|j_k|) and W_{A,B}(n)={W_{I}(A,B)= A^{i_1}B^{j_1}...
A^{i_s}B^{j_s}}_{|I|=n}.
  Gamburd-Jakobson-Sarnak raised the problem: prove that for Haar almost every
pair A, B in SO(3) the closest distance of the word of length n to the
identity, i.e. s_{A,B}(n)=min_{|I|=n} |W_{I}(A,B)-Id|, is bounded from below by
an exponential function in n. This is an analog of diophantine property for
elements of SO(3). In this paper we make first step toward understanding
diophantine properties of SO(3). We prove that s_{A,B}(n) is bounded from below
by an exponential function in n^2. We also exhibit obstructions to prove a
simple exponential in n estimate.

</DOC>
<DOC>
<DOCNO> 12699 </DOCNO>
Phase separation in a chaotic flow


  The phase separation between two immiscible liquids advected by a
bidimensional velocity field is investigated numerically by solving the
corresponding Cahn-Hilliard equation. We study how the spinodal decomposition
process depends on the presence -or absence- of Lagrangian chaos. A fully
chaotic flow, in particular, limits the growth of domains and for unequal
volume fractions of the liquids, a characteristic exponential distribution of
droplet sizes is obtained. The limiting domain size results from a balance
between chaotic mixing and spinodal decomposition, measured in terms of
Lyapunov exponent and diffusivity constant, respectively.

</DOC>
<DOC>
<DOCNO> 80827 </DOCNO>
Microcanonical Simulation of Complex Actions: The Wess Zumino Witten


  We present the main results of our microcanonical simulation of the Wess
Zumino Witten action functional. This action, being highly non-trivial and
capable of exhibiting many different phase transitions, is chosen to be
representative of general complex actions. We verify the applicability of
microcanonical simulation by successfully obtaining two of the many critical
points of the Wess Zumino Witten action. The microcanonical algorithm has the
additional advantage of exhibiting critical behaviour for a small $8\times 8$
lattice. We also briefly discuss the subtleties that, in general, arise in
simulating a complex action. Our algorithm for complex actions can be extended
to the study of
 D-branes in the Wess Zumino Witten action.

</DOC>
<DOC>
<DOCNO> 11366 </DOCNO>
Excited stationary states of trapped Bose-Einstein condensates


  We investigate the excited stationary states of Bose-Einstein condensates
trapped in harmonic potentials. We derive simple analytical approximations of
the first few eigenstates of the associated time-independent one-dimensional
Gross-Pitaevskii equation and their energies. Our results are excited state
generalizations of the Thomas-Fermi approximation of the ground state.

</DOC>
<DOC>
<DOCNO> 118637 </DOCNO>
Hydrogen-Accreting Carbon-Oxygen White Dwarfs of Low Mass: Thermal and


  Numerical experiments have been performed to investigate the thermal behavior
of a cooled down white dwarf of initial mass $M_{\rm WD} = 0.516 M_{\sun}$
which accretes hydrogen-rich matter with Z = 0.02 at the rate $\dot{M}=10^{-8}$
\msun \yrm1, typical for a recurrent hydrogen shell flash regime. The evolution
of the main physical quantities of a model during a pulse cycle is examined in
detail. From selected models in the mass range $M_{\rm WD} = 0.52\div 0.68$
\msunend, we derive the borders in the $M_{\rm WD}$ - $\dot{M}$ plane of the
steady state accretion regime when hydrogen is burned at a constant rate as
rapidly as it is accreted. The physical properties during a hydrogen shell
flash in white dwarfs accreting hydrogen-rich matter with metallicities Z =
0.001 and Z = 0.0001 are also studied. For a fixed accretion rate, a decrease
in the metallicity of the accreted matter leads to an increase in the thickness
of the hydrogen-rich layer at outburst and a decrease in the hydrogen-burning
shell efficiency. In the $M_{\rm WD}$-$\dot{M}$ plane, the borders of the
steady state accretion band are critically dependent on the metallicity of the
accreted matter: on decreasing the metallicity, the band is shifted to lower
accretion rates and its width in $\dot{M}$ is reduced.

</DOC>
<DOC>
<DOCNO> 10126 </DOCNO>
Role of Coulomb correlations in the optical spectra of semiconductor


  We present a consistent theoretical description of few-particle effects in
the optical spectra of semiconductor quantum dots, based on a
direct-diagonalization approach. We show that, because of the strong Coulomb
interaction among electrons and holes, each configuration of the confined
few-particle system leads to its characteristic signature in the optical
spectra. We discuss quantitative predictions and comparison with experiments
for both absorption and luminescence.

</DOC>
<DOC>
<DOCNO> 13925 </DOCNO>
Statistical properties of the spectrum of the QCD Dirac operator at low


  We analyze the statistical properties of the spectrum of the QCD Dirac
operator at low energy in a finite box of volume $L^4$ by means of partially
quenched Chiral Perturbation Theory (pqChPT), a low-energy effective field
theory based on the symmetries of QCD. We derive the two-point spectral
correlation function from the discontinuity of the chiral susceptibility. For
eigenvalues much smaller than $E_c=F^2/\Sigma L^2$, where $F$ is the pion decay
constant and $\Sigma$ is the absolute value of the quark condensate, our result
for the two-point correlation function coincides with the result previously
obtained from chiral Random Matrix Theory (chRMT). The departure from the chRMT
result above that scale is described by the contribution of the nonzero
momentum modes. In terms of the variance of the number of eigenvalues in an
interval containing $n$ eigenvalues on average, it results in a crossover from
a $\log n$-behavior to a $n^2 \log n$-behavior.

</DOC>
<DOC>
<DOCNO> 83415 </DOCNO>
On Exponential-Time Completeness of the Circularity Problem for


  Attribute grammars (AGs) are a formal technique for defining semantics of
programming languages. Existing complexity proofs on the circularity problem of
AGs are based on automata theory, such as writing pushdown acceptor and
alternating Turing machines. They reduced the acceptance problems of above
automata, which are exponential-time (EXPTIME) complete, to the AG circularity
problem. These proofs thus show that the circularity problem is EXPTIME-hard,
at least as hard as the most difficult problems in EXPTIME. However, none has
given a proof for the EXPTIME-completeness of the problem. This paper first
presents an alternating Turing machine for the circularity problem. The
alternating Turing machine requires polynomial space. Thus, the circularity
problem is in EXPTIME and is then EXPTIME-complete.

</DOC>
<DOC>
<DOCNO> 150759 </DOCNO>
Vortex Pair Creation on Brane-Antibrane Pair via Marginal Deformation


  It has been conjectured that the vortex solution on a D-brane - anti-D-brane
system represents a D-brane of two lower dimension. We establish this result by
first identifying a series of marginal deformations which create the vortex -
antivortex pair on the brane - antibrane system, and then showing that under
this series of marginal deformations the original D-brane - anti-D-brane system
becomes a D-brane - anti-D-brane system with two lower dimensions.
Generalization of this construction to the case of solitons of higher
codimension is also discussed.

</DOC>
<DOC>
<DOCNO> 11023 </DOCNO>
Variational Mean Field approach to the Double Exchange Model


  It has been recently shown that the double exchange Hamiltonian, with weak
antiferromagnetic interactions, has a richer variety of first and second order
transitions than previously anticipated, and that such transitions are
consistent with the magnetic properties of manganites. Here we present a
thorough discussion of the variational Mean Field approach that leads to the
these results. We also show that the effect of the Berry phase turns out to be
crucial to produce first order Paramagnetic-Ferromagnetic transitions near half
filling with transition temperatures compatible with the experimental
situation. The computation relies on two crucial facts: the use of a Mean Field
ansatz that retains the complexity of a system of electrons with off-diagonal
disorder, not fully taken into account by the Mean Field techniques, and the
small but significant antiferromagnetic superexchange interaction between the
localized spins.

</DOC>
<DOC>
<DOCNO> 118185 </DOCNO>
The NASA Astrophysics Data System: Architecture


  The powerful discovery capabilities available in the ADS bibliographic
services are possible thanks to the design of a flexible search and retrieval
system based on a relational database model. Bibliographic records are stored
as a corpus of structured documents containing fielded data and metadata, while
discipline-specific knowledge is segregated in a set of files independent of
the bibliographic data itself.
  The creation and management of links to both internal and external resources
associated with each bibliography in the database is made possible by
representing them as a set of document properties and their attributes.
  To improve global access to the ADS data holdings, a number of mirror sites
have been created by cloning the database contents and software on a variety of
hardware and software platforms.
  The procedures used to create and manage the database and its mirrors have
been written as a set of scripts that can be run in either an interactive or
unsupervised fashion.
  The ADS can be accessed at http://adswww.harvard.edu

</DOC>
<DOC>
<DOCNO> 121036 </DOCNO>
Hubble Redshift


  The dependence of luminosity distance on observed resdhift and the
cosmological parameters H and q is derived for a contracting Friedmann universe
with no cosmological constant. The result is consistent with recent supernovae
observations.

</DOC>
<DOC>
<DOCNO> 102337 </DOCNO>
Eigenvalue curves of asymmetric tridiagonal random matrices


  Random Schroedinger operators with imaginary vector potentials are studied in
dimension one. These operators are non-Hermitian and their spectra lie in the
complex plane. We consider the eigenvalue problem on finite intervals of length
n with periodic boundary conditions and describe the limit eigenvalue
distribution when n goes to infinity. We prove that this limit distribution is
supported by curves in the complex plane. We also obtain equations for these
curves and for the corresponding eigenvalue density in terms of the Lyapunov
exponent and the integrated density of states of a "reference" symmetric
eigenvalue problem. In contrast to these results, the spectrum of the limit
operator in l^2(Z) is a two dimensional set which is not approximated by the
spectra of the finite-interval operators.

</DOC>
<DOC>
<DOCNO> 99922 </DOCNO>
Quadratic Poisson algebras for two dimensional classical superintegrable


  The integrals of motion of the classical two dimensional superintegrable
systems with quadratic integrals of motion close in a restrained quadratic
Poisson algebra, whose the general form is investigated. Each classical
superintegrable problem has a quantum counterpart, a quantum superintegrable
system. The quadratic Poisson algebra is deformed to a quantum associative
algebra, the finite dimensional representations of this algebra are calculated
by using a deformed parafermion oscillator technique. It is shown that, the
finite dimensional representations of the quadratic algebra are determined by
the energy eigenvalues of the superintegrable system. The calculation of energy
eigenvalues is reduced to the solution of algebraic equations, which are
universal for all two dimensional superintegrable systems with quadratic
integrals of motion.

</DOC>
<DOC>
<DOCNO> 80978 </DOCNO>
Finite size scaling analysis of compact QED


  We describe results of a high-statistics finite size scaling analysis of 4d
compact U(1) lattice gauge theory with Wilson action at the phase transition
point. Using a multicanonical hybrid Monte Carlo algorithm we generate data
samples with more than 150 tunneling events between the metastable states of
the system, on lattice sizes up to 18^4. We performed a first analysis within
the Borgs-Kotecky finite size scaling scheme. As a result, we report evidence
for a first-order phase transition with a plaquette energy gap, G=0.02667(20),
at a transition coupling, beta_T=1.011128(11).

</DOC>
<DOC>
<DOCNO> 12689 </DOCNO>
Bi-layer Paired Quantum Hall States and Coulomb Drag


  We consider three states which are likely to be realized in bi-layer quantum
Hall systems at total Landau level filling fraction ${\nu_T}=1$. Two of these
states may be understood as paired states. One can occur as an instability of a
compressible state in the large $d/l_B$ limit, where $d$ and $l_B$ are the
interlayer distance and magnetic length. The other is the $(1,1,1)$ state,
which is expected in the small $d/l_B$ limit. We propose that the longitudinal
and Hall drag resistivities can be used to distinguish these different quantum
Hall states. The drag resistivities may be computed in a straightforward manner
using the paired state formulation.

</DOC>
<DOC>
<DOCNO> 10747 </DOCNO>
Physics of the rhythmic applause


  We discuss in detail a human scale example of the synchronization phenomenon,
namely the dynamics of the rhythmic applause. After a detailed experimental
investigation, we describe the phenomenon with an approach based on the
classical Kuramoto model. Computer simulations based on the theoretical
assumptions, reproduce perfectly the observed dynamics. We argue that a
frustration present in the system is responsible for the interesting interplay
between synchronized and unsynchronized regimes

</DOC>
<DOC>
<DOCNO> 8755 </DOCNO>
Momentum conservation and local field corrections for the response of


  We reanalyze the recently derived response function for interacting systems
in relaxation time approximation respecting density, momentum and energy
conservation. We find that momentum conservation leads exactly to the local
field corrections for both cases respecting only density conservation and
respecting density and energy conservation. This rewriting simplifies the
former formulae dramatically. We discuss the small wave vector expansion and
find that the response function shows a high frequency dependence of
$\omega^{-5}$ which allows to fulfill higher order sum rules. The momentum
conservation also resolves a puzzle about the conductivity which should only be
finite in multicomponent systems.

</DOC>
<DOC>
<DOCNO> 10712 </DOCNO>
Image restoration using the Q-Ising spin glass


  We investigate static and dynamic properties of gray-scale image restoration
(GSIR) by making use of the Q-Ising spin glass model, whose ladder symmetry
allows to take in account the distance between two spins. We thus give an
explicit expression of the Hamming distance between the original and restored
images as a function of the hyper-parameters in the mean field limit. Finally,
numerical simulations for real-world pictures are carried out to prove the
efficiency of our model.

</DOC>
<DOC>
<DOCNO> 39938 </DOCNO>
An Improved Limit on the Rate Of Decay K+ -> pi+ mu+ e-


  The experiment E865 at BNL places an upper limit on the branching ratio for
the decay K+ -> pi+ mu+ e- of 3.9x10^-11 (90% C.L.). Along with with other
results this yields a combined upper limit on this branching ratio of
2.8x10^-11. A new upper limit on the branching ratio for pi0 -> mu+ e- of
3.8x10^-10 (90% C.L.) is also established. The experiment and analysis are
described.

</DOC>
<DOC>
<DOCNO> 122774 </DOCNO>
The detection of a 1.4-h period in RW Ursa Minoris - candidate for


  CCD photometry of the classical nova RW UMi during 10 nights in 1995 through
an R filter and 14 nights in 1997 through a `clear' filter, with the 1-m Wise
telescope yields a periodic modulation in the light curve with the period
0.05912+/-0.00015 d and a semi amplitude of 0.025 mag. We discuss several
explanations for the periodicity, and suggest that it is likely to be the
orbital period of the binary system or a superhump period. RW UMi is thus a
candidate for the classical nova with the shortest known orbital period.

</DOC>
<DOC>
<DOCNO> 170747 </DOCNO>
On generalized probabilities: correlation polytopes for automaton logic


  Three extensions and reinterpretations of nonclassical probabilities are
reviewed. (i) We propose to generalize the probability axiom of quantum
mechanics to self-adjoint positive operators of trace one. Furthermore, we
discuss the Cartesian and polar decomposition of arbitrary normal operators and
the possibility to operationalize the corresponding observables. Thereby we
review and emphasize the use of observables which maximally represent the
context. (ii) In the second part, we discuss Pitowsky polytopes for automaton
logic as well as for generalized urn models and evaluate methods to find the
resulting Boole-Bell type (in)equalities. (iii) Finally, so-called ``parameter
cheats'' are introduced, whereby parameters are transformed bijectively and
nonlinearly in such a way that classical systems mimic quantum correlations and
vice versa. It is even possible to introduce parameter cheats which violate the
Boole-Bell type inequalities stronger than quantum ones, thereby trespassing
the Tsirelson limit. The price to be paid is nonuniformity.

</DOC>
<DOC>
<DOCNO> 152490 </DOCNO>
The Geometry of Fractional Branes


  By looking at fractional Dp-branes of type IIA on T_4/Z_2 as wrapped branes
and by using boundary state techniques we construct the effective low-energy
action for the fields generated by fractional branes, build their world-volume
action and find the corresponding classical geometry. The explicit form of the
classical background is consistent only outside an enhancon sphere of radius
r_e, which encloses a naked singularity of repulson-type. The perturbative
running of the gauge coupling constant, dictated by the NS-NS twisted field
that keeps its one-loop expression at any distance, also fails at r_e.

</DOC>
<DOC>
<DOCNO> 99572 </DOCNO>
Unitary representations of the 2-dimensional Euclidean group in the


  E(2) is studied as the automorphism group of the Heisenberg algebra H. The
basis in the Hilbert space K of functions on H on which the unitary irreducible
representations of the group are realized is explicitely constructed. The
addition theorem for the Kummer functions is derived.

</DOC>
<DOC>
<DOCNO> 10628 </DOCNO>
Strong Correlation to Weak Correlation Phase Transition in Bilayer


  At small layer separations, the ground state of a nu=1 bilayer quantum Hall
system exhibits spontaneous interlayer phase coherence and has a
charged-excitation gap E_g. The evolution of this state with increasing layer
separation d has been a matter of controversy. In this letter we report on
small system exact diagonalization calculations which suggest that a single
phase transition, likely of first order, separates coherent incompressible (E_g
>0) states with strong interlayer correlations from incoherent compressible
states with weak interlayer correlations. We find a dependence of the phase
boundary on d and interlayer tunneling amplitude that is in very good agreement
with recent experiments.

</DOC>
<DOC>
<DOCNO> 99963 </DOCNO>
A Survey of Noncommutative Chern Characters


  We report in this survey some new results concerning noncommutative Chern
characters: construction and the cases when they are exactly computed. The
major result indicates some clear relation of these noncommutative objects and
their commutative counterparts. This survey can be considered as the second
part of the previous survey (J. of Lie Theory vol. 3 (1993), 149-176.

</DOC>
<DOC>
<DOCNO> 122516 </DOCNO>
Illuminated, and enlightened, by GRB 991216


  We consider models for the generation of the emission line recently
discovered in the X-ray afterglow spectrum of several bursts, and especially of
GRB 991216 observed by Chandra. These observations suggest the presence of
0.1-1 solar masses of iron in the vicinity of the bursts. We show that there
are strong geometrical and kinematical constraints on the line emitting
material. We discuss several classes of models, favoring one where the line
photons are produced by reflection off the walls of a wide funnel of
semi-opening angle 45 degrees, excavated in a young (a few months old)
supernova remnant made of ~10 solar masses with radius 6x10^15 cm, and ~1 solar
mass of iron, providing strong support for the SupraNova model.

</DOC>
<DOC>
<DOCNO> 116939 </DOCNO>
Continued Monitoring of the Conditioning of the Fermilab Linac 805 MHz


  We have reported previously on the conditioning of the high-gradient
accelerating cavities in the Fermilab Linac. Automated measurements of the
sparking rate have been recorded since 1994 and are reported here. The sparking
rate has declined since the beginning, but there are indications that this rate
may have leveled off now. The X-rays emitted by the cavities are continuing to
decrease.

</DOC>
<DOC>
<DOCNO> 10215 </DOCNO>
Crystal Field -AS_z^2 Does Not Produce One-Phonon Transitions With Delta


  Recently Leuenbeger and Loss suggested a theory of phonon-assisted relaxation
in a molecular nanomagnet Mn-12 that "contrary to previous results is in
reasonably good agreement ... with all experimental parameter values known so
far". The purpose of this Comment is to show that the model of Leuenberger and
Loss and its comparison with experiment are premised upon their incorrect use
of the linear formula for the strain tensor. The spin-phonon coupling
introduced by Leuenberger and Loss disappears if the nonlinear term in the
strain tensor is taken into account.

</DOC>
<DOC>
<DOCNO> 101227 </DOCNO>
Noncommutative Korteweg-de-Vries Equation


  We construct a deformation quantized version (ncKdV) of the KdV equation
which possesses an infinite set of conserved densities. Solutions of the ncKdV
are obtained from solutions of the KdV equation via a kind of Seiberg-Witten
map. The ncKdV is related to a modified ncKdV equation by a noncommutative
Miura transformation.

</DOC>
<DOC>
<DOCNO> 99614 </DOCNO>
PT symmetric form of the Hulthen potential


  The fourth, missing example of an exactly solvable complex potential with PT
symmetry V(x) = [V(-x)]^* defined on a bent contour and leading, at the real
energies, to the Jacobi polynomial wave functions is found in a generalized
Hulthen interaction.

</DOC>
<DOC>
<DOCNO> 101955 </DOCNO>
A proof of Pieri's formula using generalized Schensted insertion


  We provide a generalization of the Schensted insertion algorithm for
rc-graphs of Bergeron an Billey \cite{bb}. The new algorithm is used to give a
new proof of Pieri's formula.

</DOC>
<DOC>
<DOCNO> 119462 </DOCNO>
Redshift Distortions and Clustering in the PSCz Survey


  We have constrained the redshift-distortion parameter $\beta \equiv
\Omega^{0.6}/b$ and the real-space power spectrum of the IRAS PSCz survey using
a spherical-harmonic redshift-distortion analysis combined with a data
compression method which is designed to deal with correlated parameters. Our
latest result, $\beta=0.4 \pm 0.1$, strongly rules out $\beta=1$.

</DOC>
<DOC>
<DOCNO> 150464 </DOCNO>
Conserved charges and supersymmetry in principal chiral and WZW models


  Conserved and commuting charges are investigated in both bosonic and
supersymmetric classical chiral models, with and without Wess-Zumino terms. In
the bosonic theories, there are conserved currents based on symmetric invariant
tensors of the underlying algebra, and the construction of infinitely many
commuting charges, with spins equal to the exponents of the algebra modulo its
Coxeter number, can be carried out irrespective of the coefficient of the
Wess-Zumino term. In the supersymmetric models, a different pattern of
conserved quantities emerges, based on antisymmetric invariant tensors. The
current algebra is much more complicated than in the bosonic case, and it is
analysed in some detail. Two families of commuting charges can be constructed,
each with finitely many members whose spins are exactly the exponents of the
algebra (with no repetition modulo the Coxeter number). The conserved
quantities in the bosonic and supersymmetric theories are only indirectly
related, except for the special case of the WZW model and its supersymmetric
extension.

</DOC>
<DOC>
<DOCNO> 102569 </DOCNO>
The Generalized Metrical Multi-Time Lagrange Space of Relativistic


  The paper constructs a generalized metrical multi-time Lagrange space, which
allows a natural development of relativistic geometrical optics theories, in a
general setting.

</DOC>
<DOC>
<DOCNO> 85435 </DOCNO>
N = 3 chiral supergravity compatible with the reality condition and


  We obtain N = 3 chiral supergravity (SUGRA) compatible with the reality
condition by applying the prescription of constructing the chiral Lagrangian
density from the usual SUGRA. The $N = 3$ chiral Lagrangian density in
first-order form, which leads to the Ashtekar's canonical formulation, is
determined so that it reproduces the second-order Lagrangian density of the
usual SUGRA especially by adding appropriate four-fermion contact terms. We
show that the four-fermion contact terms added in the first-order chiral
Lagrangian density are the non-minimal terms required from the invariance under
first-order supersymmetry transformations. We also discuss the case of higher N
theories, especially for N = 4 and N = 8.

</DOC>
<DOC>
<DOCNO> 84534 </DOCNO>
The renormalized stress tensor in Kerr space-time: general results


  We derive constraints on the form of the renormalized stress tensor for
states on Kerr space-time based on general physical principles: symmetry, the
conservation equations, the trace anomaly and regularity on (sections of) the
event horizon. This is then applied to the physical vacua of interest. We
introduce the concept of past and future Boulware vacua and discuss the
non-existence of a state empty at both scri- and scri+. By calculating the
stress tensor for the Unruh vacuum at the event horizon and at infinity, we are
able to check our earlier conditions. We also discuss the difficulties of
defining a state equivalent to the Hartle-Hawking vacuum and comment on the
properties of two candidates for this state.

</DOC>
<DOC>
<DOCNO> 70766 </DOCNO>
Hybrid mesons from lattice QCD


  Recent lattice simulation studies of heavy-quark hybrid mesons in which the
quark and antiquark are bound together by an excited gluon field are
summarized.

</DOC>
<DOC>
<DOCNO> 121679 </DOCNO>
Ion $H_2^+$ can dissociate in a strong magnetic field


  In framework of a variational method the molecular ion $H_2^+$ in a magnetic
field is studied. An optimal form of the vector potential corresponding to a
given magnetic field (gauge fixing) is chosen variationally. It is shown that
for any magnetic field strength as well as for any orientation of the molecular
axis the system $(ppe)$ possesses a minimum in the potential energy. The stable
configuration always corresponds to elongation along the magnetic line.
However, for magnetic fields $B \gtrsim 5\times 10^{11} G$ and some
orientations the ion $H_2^+$ becomes unstable decaying to $H{-atom} + p$.

</DOC>
<DOC>
<DOCNO> 11545 </DOCNO>
Reversed anisotropies and thermal contraction of FCC (110) surfaces


  The observed anisotropies of surface vibrations for unreconstructed FCC metal
(110) surfaces are often reversed from the "common sense" expectation. The
source of these reversals is investigated by performing ab initio density
functional theory calculations to obtain the surface force constant tensors for
Ag(110), Cu(110) and Al(110). The most striking result is a large enhancement
in the coupling between the first and third layers of the relaxed surface,
which strongly reduces the amplitude of out-of-plane vibrations of atoms in the
first layer. This also provides a simple explanation for the thermal
contraction of interlayer distances. Both the anisotropies and the thermal
contraction arise primarily as a result of the bond topology, with all three
(110) surfaces showing similar behavior.

</DOC>
<DOC>
<DOCNO> 8135 </DOCNO>
Impurity spin dynamics in 2D antiferromagnets and superconductors


  We discuss the universal theory of localized impurities in the paramagnetic
state of 2D antiferromagnets where the spin gap is assumed to be significantly
smaller than a typical exchange energy. We study the impurity spin
susceptibility near the host quantum transition from a gapped paramagnet to a
Neel state, and we compute the impurity-induced damping of the spin-1 mode of
the gapped antiferromagnet. Under suitable conditions our results apply also to
d-wave superconductors.

</DOC>
<DOC>
<DOCNO> 117180 </DOCNO>
Dipole Septum Magnet in the Fast Kicker System for Multi-Axis Advanced


  Here we present designs for a static septum magnet with two adjacent
apertures where ideally one aperture has a uniform dipole field and the other
zero field. Two designs are considered. One is a true septum magnet with a thin
layer of coils and materials separating the dipole field region from the null
field region. During the beam switching process, the intense electron beam will
spray across this material septum leading to concerns on beam control, vacuum
quality, radiation damage, etc. due to the lost particles. Therefore, another
configuration without a material septum is also considered. With this
configuration it is more difficult to achieve high field quality near the
transition region. Shaped shims are designed to limit the degradation of beam
quality (emittance growth). This approach is closely related to a previous
septum magnet design with two oppositely oriented dipole field regions
presented by the authors [1]. Simulations are performed to obtain the magnetic
field profile in both designs. A PIC simulation is used to transport a beam
slice consisting of several thousand particles through the magnet to estimate
emittance growth in the magnet due to field non-uniformity.

</DOC>
<DOC>
<DOCNO> 122959 </DOCNO>
First Results from the SPICES Survey


  We present first results from SPICES, the Spectroscopic, Photometric,
Infrared-Chosen Extragalactic Survey. SPICES is comprised of four ~30 square
arcminute high Galactic latitude fields with deep BRIzJK imaging reaching
depths of ~25th magnitude (AB) in the optical and ~23rd magnitude (AB) in the
near-infrared. To date we have 626 spectroscopic redshifts for
infrared-selected SPICES sources with K<20 (Vega). The project is poised to
address galaxy formation and evolution to redshift z~2. We discuss initial
results from the survey, including the surface density of extremely red objects
and the fraction of infrared sources at z>1. One of the SPICES fields has been
the target of a deep 190 ksec Chandra exposure; we discuss initial results from
analysis of that data set. Finally, we briefly discuss a successful campaign to
identify high-redshift sources in the SPICES fields.

</DOC>
<DOC>
<DOCNO> 70341 </DOCNO>
Post-inflationary brane cosmology


  The brane cosmology has invoked new challenges to the usual Big Bang
cosmology. In this paper we present a brief account on thermal history of the
post-inflationary brane cosmology. We have realized that it is not obvious that
the post-inflationary brane cosmology would always deviate from the standard
Big Bang cosmology. However, if it deviates some stringent conditions on the
brane tension are to be satisfied. In this regard we study various implications
on gravitino production and its abundance. We discuss Affleck-Dine mechanism
for baryogenesis and make some comments on moduli and dilaton problems in this
context.

</DOC>
<DOC>
<DOCNO> 70693 </DOCNO>
Radion effects on the production of an intermediate-mass scalar and Z at


  We have studied the $e^+ e^- \to Z \phi_i \to Z jj$ process, where $\phi_i$
is the Higgs and/or radion bosons. The implications of the radion effects on
the preliminary ALEPH data are also discussed. The case of the lighter radion
than Higgs boson is disfavored by the ALEPH analyses of the $b$ tagged four-jet
data, since the radion predominantly decays into two gluon jets due to the QCD
trace anomaly. If the radion is highly degenerate in mass with the Higgs, the
cross section can be increased more than at one sigma level, with natural scale
of the vacuum expectation value of the radion.

</DOC>
<DOC>
<DOCNO> 123057 </DOCNO>
The Intracluster Medium in z > 1 Galaxy Clusters


  The Chandra X-ray Observatory was used to obtain a 190 ks image of three high
redshift galaxy clusters in one observation. The results of our analysis of
these data are reported for the two z > 1 clusters in this Lynx field,
including the most distant known X-ray selected cluster. Spatially-extended
X-ray emission was detected from both these clusters, indicating the presence
of hot gas in their intracluster media. A fit to the X-ray spectrum of
RX J0849+4452, at z=1.26, yields a temperature of kT = 5.8^{+2.8}_{-1.7} keV.
Using this temperature and the assumption of an isothermal sphere, the total
mass of RX J0849+4452 is found to be 4.0^{+2.4}_{-1.9} X 10^{14} h_{65}^{-1}
M_{\sun} within r = 1 h_{65}^{-1} Mpc. The T_x for RX J0849+4452 approximately
agrees with the expectation based on its L_{bol} = 3.3^{+0.9}_{-0.5} X 10^{44}$
erg s$^{-1} according to the low redshift L_x - T_x relation. The very
different distributions of X-ray emitting gas and of the red member galaxies in
the two z > 1 clusters, in contrast to the similarity of the optical/IR colors
of those galaxies, suggests that the early-type galaxies mostly formed before
their host clusters.

</DOC>
<DOC>
<DOCNO> 118187 </DOCNO>
Infrared spectroscopy of NGC 1068: Probing the obscured ionizing AGN


  The ISO-SWS 2.5-45 um infrared spectroscopic observations of the nucleus of
the Seyfert 2 galaxy NGC 1068 (see companion paper) are combined with a
compilation of UV to IR narrow emission line data to determine the spectral
energy distribution (SED) of the obscured extreme-UV continuum that
photoionizes the narrow line emitting gas in the active galactic nucleus. We
search a large grid of gas cloud models and SEDs for the combination that best
reproduces the observed line fluxes and NLR geometry. Our best fit model
reproduces the observed line fluxes to better than a factor of 2 on average and
is in general agreement with the observed NLR geometry. It has two gas
components that are consistent with a clumpy distribution of dense outflowing
gas in the center and a more extended distribution of less dense and more
clumpy gas farther out that has no net outflow. The best fit SED has a deep
trough at ~4 Ryd, which is consistent with an intrinsic Big Blue Bump that is
partially absorbed by ~6x10^19 cm^-2 of neutral hydrogen interior to the NLR.

</DOC>
<DOC>
<DOCNO> 11109 </DOCNO>
Numerical Results for the Hubbard Model: Implications for the High Tc


  Numerical studies of the Hubbard model and its strong-coupling form, the t-J
model, show evidence for antiferromagnetic, d_{x^2-y^2}-pairing and stripe
correlations which remind one of phenomena seen in the layered cuprate
materials. Here, we ask what these numerical results imply about various
scenarios for the pairing mechanism.

</DOC>
<DOC>
<DOCNO> 8048 </DOCNO>
Tractable non-local correlation density functionals for flat surfaces


  A systematic approach for the construction of a density functional for van
der Waals interactions that also accounts for saturation effects is described,
i.e. one that is applicable at short distances. A very efficient method to
calculate the resulting expressions in the case of flat surfaces, a method
leading to an order reduction in computational complexity, is presented.
Results for the interaction of two parallel jellium slabs are shown to agree
with those of a recent RPA calculation (J.F. Dobson and J. Wang, Phys. Rev.
Lett. 82, 2123 1999). The method is easy to use; its input consists of the
electron density of the system, and we show that it can be successfully
approximated by the electron densities of the interacting fragments. Results
for the surface correlation energy of jellium compare very well with those of
other studies. The correlation-interaction energy between two parallel jellia
is calculated for all separations d, and substantial saturation effects are
predicted.

</DOC>
<DOC>
<DOCNO> 71585 </DOCNO>
The Higgs as a Supersymmetric Partner, with a New Interpretation of


  An unconventional version of supersymmetry leads to the following highly
testable predictions: (1) The Higgs boson has an R-parity of -1, so it can only
be produced as one member of a pair of superpartners. (2) The only
superpartners are scalar bosons, so neutralinos etc. do not exist. (3) The most
likely candidate for cold dark matter is therefore a sneutrino. (4) The Higgs
and other bosonic superpartners have an unconventional equation of motion.
These predictions are associated with new interpretations of Yukawa couplings,
supersymmetry, gauge fields, and Lorentz invariance.

</DOC>
<DOC>
<DOCNO> 10665 </DOCNO>
Ginzburg-Landau theory of Fulde-Ferrell-Larkin-Ovchinnikov states in


  We derive the Ginzburg-Landau theory of unconventional singlet
superconductors in the presence of a Zeeman field and impurities, in order to
examine the resulting Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phases. We show
that the behavior of the FFLO phases in unconventional superconductors in the
presence of impurities is qualitatively different from that found for s-wave
superconductors.

</DOC>
<DOC>
<DOCNO> 84501 </DOCNO>
The role of acceleration and locality in the twin paradox


  We study the role of acceleration in the twin paradox. From the coordinate
transformation that relates an accelerated and an inertial observer we find
that, from the point of view of the accelerated observer, the rate of the
differential lapses of time depends not only on the relative velocity, but also
on the product of the acceleration and the distance between the observers.
However, this result does not have a direct operational interpretation because
an observer at a certain position can measure only physical quantities that are
defined at the same position. For local measurements, the asymmetry between the
two observers can be attributed to the fact that noninertial coordinate
systems, contrary to inertial coordinate systems, can be correctly interpreted
only locally.

</DOC>
<DOC>
<DOCNO> 169654 </DOCNO>
Effects of Dicke superradiance in context of the one-atom maser


  We consider a micromaser model to study the influence of Dicke superradiance
in the context of the one-atom maser. The model involves a microwave cavity
into which two-level Rydberg atoms are pumped in pairs. We consider a random
pump mechanism which allows the presence of at most one pair of atoms in the
cavity at any time. We analyze the differences between the present system,
called the Dicke micromaser, and an equivalently pumped conventional one-atom
micromaser. These differences are attributed to the Dicke cooperativity in the
two-atom system. We also show that the two-atom Dicke micromaser is equivalent
to a one-atom cascade two-photon micromaser. With the introduction of a
one-photon detuning, the present theory further describes a true two-photon
micromaser. We discuss in detail the role of one-photon detuning in the
mechanism of a one-atom two-photon micromaser. This leads us to point out that
the two-atom cavity dynamics can be verified by a proper scaling of the results
from an equivalent one-atom two-photon micromaser.

</DOC>
<DOC>
<DOCNO> 71261 </DOCNO>
Impact parameter dependence of parton densities at low x


  We consider impact parameter dependence of the polarized and unpolarized
parton densities. Unitarity does not allow factorization of these structure
functions over the Bjorken x and the impact parameter b variables. On the basis
of the particular geometrical model approach we conclude that spin of
constituent quark may have a significant orbital angular momentum component
which can manifest itself through the peripherality of the spin dependent
structure functions.

</DOC>
<DOC>
<DOCNO> 68694 </DOCNO>
Complementarity of the Maldacena and Randall-Sundrum Pictures


  We revive an old result, that one-loop corrections to the graviton propagator
induce 1/r^3 corrections to the Newtonian gravitational potential, and compute
the coefficient due to closed loops of the U(N) {\cal N}=4 super-Yang-Mills
theory that arises in Maldacena's AdS/CFT correspondence. We find exact
agreement with the coefficient appearing in the Randall-Sundrum brane-world
proposal. This provides more evidence for the complementarity of the two
pictures.

</DOC>
<DOC>
<DOCNO> 116688 </DOCNO>
Spectral Dependence of Polarized Radiation due to Spatial Correlations


  We study the polarization of light emitted by spatially correlated sources.
We show that in general polarization acquires nontrivial spectral dependence
due to spatial correlations. The spectral dependence is found to be absent only
for a special class of sources where the correlation length scales as the
wavelength of light. We further study the cross correlations between two
spatially distinct points that are generated due to propagation. It is found
that such cross correlation leads to sufficiently strong spectral dependence of
polarization which can be measured experimentally.

</DOC>
<DOC>
<DOCNO> 170391 </DOCNO>
Violations of Bell Inequalities for Measurements with Macroscopic


  We suggest to test the premise of ``macroscopic local realism'' which is
sufficient to derive Bell inequalities when measurements of photon number are
only accurate to an uncertainty of order $n$ photons, where $n$ is macroscopic.
Macroscopic local realism is only sufficient to imply, in the context of the
original Einstein-Podolsky-Rosen argument, fuzzy ``elements of reality'' which
have a macroscopic indeterminacy. We show therefore how the violation of local
realism in the presence of macroscopic uncertainties implies the failure of
``macroscopic local realism''. Quantum states violating this macroscopic local
realism are presented.

</DOC>
<DOC>
<DOCNO> 13857 </DOCNO>
The Dynamics of Efficiency: A Simple Model


  We propose a simple model that describes the dynamics of efficiencies of
competing agents. Agents communicate leading to increase of efficiencies of
underachievers, and an efficiency of each agent can increase or decrease
irrespectively of other agents. When the rate of deleterious changes exceeds a
certain threshold, the economy falls into a stagnant phase. In the opposite
situation, the economy improves with asymptotically constant rate and the
efficiency distribution has a finite width. The leading algebraic corrections
to the asymptotic growth rate are also computed.

</DOC>
<DOC>
<DOCNO> 120760 </DOCNO>
Energy Diagnoses of Nine Infrared Luminous Galaxies Based on 3--4 Micron


  The energy sources of nine infrared luminous galaxies (IRLGs) are diagnosed
based on their ground-based 3--4 $\mu$m spectra. Both the equivalent width of
the 3.3 $\mu$m polycyclic aromatic hydrocarbon (PAH) emission feature and the
3.3 $\mu$m PAH to far-infrared luminosity ratio ($L_{3.3}/L_{\rm FIR}$) are
analyzed. Assuming nuclear compact starburst activity in these sources produces
the 3.3 $\mu$m PAH emission as strongly as that in starburst galaxies with
lower far-infrared luminosities, the followings results are found: For six
IRLGs, both the observed equivalent widths and the $L_{3.3}/L_{\rm FIR}$ ratios
are too small to explain the bulk of their far-infrared luminosities by compact
starburst activity, indicating that active galactic nucleus (AGN) activity is a
dominant energy source. For the other three IRLGs, while the 3.3 $\mu$m PAH
equivalent widths are within the range of starburst galaxies, the
$L_{3.3}/L_{\rm FIR}$ ratios after correction for screen dust extinction are a
factor of $\sim$3 smaller. The uncertainty in the dust extinction correction
factor and in the scatter of the intrinsic $L_{3.3}/L_{\rm FIR}$ ratios for
starburst galaxies do not allow a determination of the ultimate energy sources
for these three IRLGs.

</DOC>
<DOC>
<DOCNO> 101529 </DOCNO>
Multiscale Analysis of RMS Envelope Dynamics


  We present applications of variational -- wavelet approach to different forms
of nonlinear (rational) rms envelope equations. We have the representation for
beam bunch oscillations as a multiresolution (multiscales) expansion in the
base of compactly supported wavelet bases.

</DOC>
<DOC>
<DOCNO> 69609 </DOCNO>
Monopoles, Axions and Intermediate Mass Dark Matter


  We present a solution to the cosmological problem encountered in
(supersymmetric) grand unified theories due to copious monopole production at
the end of hybrid inflation. By employing thermal inflation ``driven'' by the
U(1) axion symmetry, the superheavy monopole flux can be naturally suppressed
to values that should be accessible to dedicated large scale experiments. The
U(1) axion symmetry also helps generate the right magnitude for the mu term of
the minimal supersymmetric standard model. An important by-product is the
predicted existence of stable or very long-living fermions possessing
intermediate scale masses of order 10^{12} GeV. Their presence is required for
implementing thermal inflation, and their stability is due to a Z_2 symmetry.
They may constitute a sizable fraction of cold dark matter, and possibly help
explain the ultra-high energy cosmic ray events. The rest of cold dark matter
may consist of axions. Although our discussion is carried out within the
framework of supersymmetric SU(4)_c x SU(2)_L x SU(2)_R, it can be extended to
other grand unified gauge groups such as SU(3)_c x SU(3)_L x SU(3)_R or SO(10).

</DOC>
<DOC>
<DOCNO> 10639 </DOCNO>
A lattice-Boltzmann model for interacting amphiphilic fluids


  We develop our recently proposed lattice-Boltzmann method for the
non-equilibrium dynamics of amphiphilic fluids (Chen, Boghosian, Coveney and
Nekovee, Proc. Roy. Soc. London A, 456, 1431 (2000).) Our method maintains an
orientational degree of freedom for the amphiphilic species and models fluid
interactions at a microscopic level by introducing self-consistent mean-field
forces between the particles into the lattice-Boltzmann dynamics, in a way that
is consistent with kinetic theory. We present the results of extensive
simulations in two dimensions which demonstrate the ability of our model to
capture the correct phenomenology of binary and ternary amphiphilic fluids.

</DOC>
<DOC>
<DOCNO> 70749 </DOCNO>
Four-neutrino oscillation solutions of the atmospheric neutrino anomaly


  In the context of neutrino scenarios characterized by four (three active plus
one sterile) neutrino species and by mass spectra with two separated doublets,
we analyze solutions to the atmospheric neutrino anomaly which smoothly
interpolate between \nu_\mu-->\nu_\tau and \nu_\mu-->\nu_s oscillations. We
show that, although the Super-Kamiokande data disfavor the pure \nu_\mu-->\nu_s
channel, they do not exclude its occurrence, with sizable amplitude, in
addition to the \nu_\mu-->\nu_\tau channel. High energy muon data appear to be
crucial in assessing the relative amplitude of active and sterile neutrino
oscillations. It is also qualitatively shown that such atmospheric \nu
solutions are compatible with analogous solutions to the solar neutrino
problem, which involve oscillations of \nu_e in both sterile and active states.

</DOC>
<DOC>
<DOCNO> 151543 </DOCNO>
Boundary Fixed Points, Enhanced Gauge Symmetry and Singular Bundles on


  We investigate certain fixed points in the boundary conformal field theory
representation of type IIA D-branes on Gepner points of K3. They correspond
geometrically to degenerate brane configurations, and physically lead to
enhanced gauge symmetries on the world-volume. Non-abelian gauge groups arise
if the stabilizer group of the fixed points is realized projectively, which is
similar to D-branes on orbifolds with discrete torsion. Moreover, the fixed
point boundary states can be resolved into several irreducible components.
These correspond to bound states at threshold and can be viewed as (non-locally
free) sub-sheaves of semi-stable sheaves. Thus, the BCFT fixed points appear to
carry two-fold geometrical information: on the one hand they probe the boundary
of the instanton moduli space on K3, on the other hand they probe discrete
torsion in D-geometry.

</DOC>
<DOC>
<DOCNO> 119281 </DOCNO>
Recent Observations of X-Ray Emission from Galactic Binary Neutron Stars


  Recent measurements of young accreting binary neutron stars are determining
more precise magnetic field and accretion parameters. A low magnetic field
accreting, millisecond pulsar has finally been found in a binary burster. At
least 20 low-mass binaries have exhibited high frequency oscillations,
300--1200 Hertz. The majority have, for some range of luminosity, the pair of
quasiperiodic oscillations that have never been seen in a black hole candidate.
Recent evidence from burst oscillations strengthens the case that the
difference frequency of this pair is close to the spin frequency of the neutron
star. These oscillations are correlated with the spectra, luminosity, and low
frequency oscillations. Quasiperiodic oscillations are also seen sometimes in
strong magnetic field pulsars, where their origin can be closely examined.

</DOC>
<DOC>
<DOCNO> 12761 </DOCNO>
Zero-Temperature Dynamics of Plus/Minus J Spin Glasses and Related


  We study zero-temperature, stochastic Ising models sigma(t) on a
d-dimensional cubic lattice with (disordered) nearest-neighbor couplings
independently chosen from a distribution mu on R and an initial spin
configuration chosen uniformly at random. Given d, call mu type I (resp., type
F) if, for every x in the lattice, sigma(x,t) flips infinitely (resp., only
finitely) many times as t goes to infinity (with probability one) --- or else
mixed type M. Models of type I and M exhibit a zero-temperature version of
``local non-equilibration''. For d=1, all types occur and the type of any mu is
easy to determine. The main result of this paper is a proof that for d=2,
plus/minus J models (where each coupling is independently chosen to be +J with
probability alpha and -J with probability 1-alpha) are type M, unlike
homogeneous models (type I) or continuous (finite mean) mu's (type F). We also
prove that all other noncontinuous disordered systems are type M for any d
greater than or equal to 2. The plus/minus J proof is noteworthy in that it is
much less ``local'' than the other (simpler) proof. Homogeneous and plus/minus
J models for d greater than or equal to 3 remain an open problem.

</DOC>
<DOC>
<DOCNO> 9909 </DOCNO>
Comment on ``Search for two-scale localization in disordered wires in a


  In a recent work Schomerus and Beenakker [Phys. Rev. Lett. 84, 3927 (2000)]
tried to check numerically our prediction about a two-scale localization in
disordered wires in a weak magnetic field. According to our theory an
exponential decay of wave functions with the localization length of the
orthogonal ensemble is followed at larger distances by another exponential
decay with the length of the unitary ensemble. Studying the transmittance,
Schomerus and Beenakker did not confirm our theory. The most probable
explanation they suggested is that only rare states could have the two scales
while ``typical'' states have the only localization length. We suggest another
explanation of the discrepancy, namely, that the Borland conjecture relating
the transmittance and wave functions to each other may not be used for studying
the effect of the magnetic field on the tails of wave functions.

</DOC>
<DOC>
<DOCNO> 151684 </DOCNO>
Tensionless Branes and Discrete Gauge Symmetry


  We show that the tensionless branes found recently on non-BPS D-branes using
non-commutative field theory are in fact gauge equivalent to the vacuum under a
discrete gauge symmetry. We also give a simple construction of the D(2p)-branes
in IIA theory starting from a single non-BPS D9-brane.

</DOC>
<DOC>
<DOCNO> 8459 </DOCNO>
On the evaluation of the specific heat and general off-diagonal n-point


  We present an efficient way to compute diagonal and off-diagonal n-point
correlation functions for quantum spin-systems within the loop algorithm. We
show that the general rules for the evaluation of these correlation functions
take an especially simple form within the framework of directed loops. These
rules state that contributing loops have to close coherently. As an application
we evaluate the specific heat for the case of spin chains and ladders.

</DOC>
<DOC>
<DOCNO> 152443 </DOCNO>
On Isolated Vacua and Background Independence


  I argue that isolated vacua of M-theory, cannot in any conventional way be
said to live in the same theory as other disconnected parts of the moduli
space. The usual field theoretic mechanisms, which allow an observer in one
disconnected component of a moduli space to verify the existence of other
components, fail. The failure is a consequence of robust properties of black
holes. When barriers between components are much smaller than the Planck scale,
the usual field theoretic picture is approximately valid.

</DOC>
<DOC>
<DOCNO> 174570 </DOCNO>
Evidence for a three-nucleon-force effect in proton-deuteron elastic


  Developments in spin-polarized internal targets for storage rings have
permitted measurements of 197 MeV polarized protons scattering from vector
polarized deuterons. This work presents measurements of the polarization
observables A_y, iT_11, and C_y,y in proton-deuteron elastic scattering. When
compared to calculations with and without three-nucleon forces, the
measurements indicate that three-nucleon forces make a significant contribution
to the observables. This work indicates that three-body forces derived from
static nuclear properties appear to be crucial to the description of dynamical
properties.

</DOC>
<DOC>
<DOCNO> 121766 </DOCNO>
Chandra X-ray Observatory Detection of Extended X-ray Emission from the


  We report the detection of well resolved, extended X-ray emission from the
young planetary nebula BD+303639 using the Advanced CCD Imaging Spectrometer
(ACIS) aboard the Chandra X-ray Observatory. The X-ray emission from BD+303639
appears to lie within, but is concentrated to one side of, the interior of the
shell of ionized gas seen in high-resolution optical and IR images. The
relatively low X-ray temperature (Tx ~ 3x10^6 K) and asymmetric morphology of
the X-ray emission suggests that conduction fronts are present and/or mixing of
shock-heated and photoionized gas has occurred and, furthermore, hints at the
presence of magnetic fields. The ACIS spectrum suggests that the X-ray emitting
region is enriched in the products of helium burning. Our detection of extended
X-ray emission from BD+303639 demonstrates the power and utility of Chandra
imaging as applied to the study of planetary nebulae.

</DOC>
<DOC>
<DOCNO> 100504 </DOCNO>
Induced Representations of the Two Parametric Quantum Deformation


  The two-parametric quantum superalgebra $U_{p,q}[gl(2/2)]$ and its induced
representations are considered. A method for constructing all
finite-dimensional irreducible representations of this quantum superalgebra is
also described in detail. It turns out that finite-dimensional representations
of the two-parametric $U_{p,q}[gl(2/2)]$, even at generic deformation
parameters, are not simply trivial deformations from those of the classical
superalgebra $gl(2/2)$, unlike the one-parametric cases.

</DOC>
<DOC>
<DOCNO> 116584 </DOCNO>
Coriolis force in Geophysics: an elementary introduction and examples


  We show how Geophysics may illustrate and thus improve classical Mechanics
lectures concerning the study of Coriolis force effects. We are then interested
in atmospheric as well as oceanic phenomena we are familiar with, and are for
that reason of pedagogical and practical interest. Our aim is to model them in
a very simple way to bring out the physical phenomena that are involved.

</DOC>
<DOC>
<DOCNO> 151290 </DOCNO>
Fermionic Zero Modes and Spontaneous Symmetry Breaking on the Light


  Spontaneous symmetry breaking is studied within a simple version of the
light-front sigma model with fermions. Its vacuum structure is derived by an
implementation of global symmetries in terms of unitary operators in a finite
volume with periodic fermi field. Due to the dynamical fermion zero mode, the
vector and axial U(1) charges do not annihilate the light-front vacuum. The
latter is transformed into a continuous set of degenerate vacuum states,
leading to to the spontaneous breakdown of the axial symmetry. The existence of
associated massless Nambu-Goldstone boson is demonstrated.

</DOC>
<DOC>
<DOCNO> 99565 </DOCNO>
Graphical Compositions 1: Basic Enumeration


  Graph compositions generalize both integer compositions and partitions of a
finite set. We develop formulas, generating functions and recurrence relations
for composition counting functions for several families of graphs.

</DOC>
<DOC>
<DOCNO> 40235 </DOCNO>
Studying the Top Quark


  The top quark, discovered at the Fermilab Tevatron collider in 1995, is the
heaviest known elementary particle. Its large mass suggests that it may play a
special role in nature. It behaves differently from the other known quarks due
both to its large mass and its short lifetime. Thus far we have only crude
measurements of the properties of the top quark, such as its mass, weak
interactions, strong interactions, and decay modes. These measurements will be
made more precise when the Tevatron begins operation again in 2001. I review
the present status of these measurements, and discuss their anticipated
improvement.

</DOC>
<DOC>
<DOCNO> 8259 </DOCNO>
Bouncing-ball tunneling in quantum dots


  We show that tunneling through quantum dots can be completely dominated by
states quantized on stable bouncing-ball orbits. The fingerprints of
bouncing-ball tunneling are sequences of Coulomb blockade peaks with strongly
correlated peak height and asymmetric peak line shape. Our results are in
agreement with the striking correlations of peak height and transmission phase
found in recent interference experiments with quantum dots.

</DOC>
<DOC>
<DOCNO> 118890 </DOCNO>
GRB000301C with peculiar afterglow emission


  The CCD magnitudes in Johnson V and Cousins R and I photometric passbands are
determined for GRB 000301C afterglow starting ~ 1.5 day after the gamma-ray
burst. In fact we provide the earliest optical observations for this burst.
Light curves of the afterglow emissions in U, B, V, R, I, J and K' passbands
are obtained by combining the present measurements with the published data.
Flux decay shows a very uncommon variation relative to other well observed
GRBs. Overall, there is a steepening of the optical and near-infrared flux
decay caused by a geometric and sideways expanding jet. This is superimposed by
a short term variability especially during early time (Delta t < 8 days). The
cause of variability is not well understood, though it has occurred
simultaneously with similar amplitude in all the filters. We derive the early
and late time flux decay constants using jet model. The late time flux decay is
the steepest amongst the GRB OTs observed so far with alpha ~ 3. Steepening in
the flux decay seems to have started simultaneously around Delta t ~ 7.6 day in
all passbands. The value of spectral index in the optical-near IR region is ~
-1.0. Redshift determination with z=2.0335 indicates cosmological origin of the
GRB having a luminosity distance of 16.6 Gpc. Thus it becomes the second
farthest amongst the GRBs with known distances. An indirect estimate of the
fluence > 20 keV indicates, if isotropic,> =10^53 ergs of release of energy.
The enormous amount of released energy will be reduced, if the radiation is
beamed which is the case for this event. Using a jet break time of 7.6 days, we
infer a jet opening angle of ~ 0.15 radian. This means the energy released is
reduced by a factor of ~ 90 relative to the isotropic value.

</DOC>
<DOC>
<DOCNO> 39635 </DOCNO>
Low energy atmospheric muon neutrinos in MACRO


  We present the measurement of two event samples induced by atmospheric
$\nu_\mu$ of average energy $ \bar {E}_\nu \sim 4 GeV$. In the first sample,
the neutrino interacts inside the MACRO detector producing an upward-going muon
leaving the apparatus. The ratio of the number of observed to expected events
is $ 0.57 \pm0.05_{stat} \pm0.06_{syst} \pm0.14_{theor}$ with an angular
distribution similar to that expected from the Bartol atmospheric neutrino
flux. The second is a mixed sample of internally produced downward-going muons
and externally produced upward-going muons stopping inside the detector. These
two subsamples are selected by topological criteria; the lack of timing
information makes it impossible to distinguish stopping from downgoing muons.
The ratio of the number of observed to expected events is $0.71 \pm 0.05_{stat}
\pm0.07_{syst} \pm0.18_{theor}$ . Using the ratio of the two subsamples (for
which most theoretical uncertainties cancel) we can test the pathlength
dependence of the oscillation hypothesis. The probability of agreement with the
no-oscillation hypothesis is 5% .
  The deviations of our observations from the expectations has a preferred
interpretation in terms of $\nu_\mu$ oscillations with maximal mixing and
$\Delta m^2 \sim 10^{-3} \div 10^{-2} eV^2$. These parameters are in agreement
with our results from upward throughgoing muons, induced by $\nu_\mu$ of much
higher energies.

</DOC>
<DOC>
<DOCNO> 68178 </DOCNO>
Numerical Solution of the Spinless Salpeter Equation by a Semianalytical


  In quantum theory, the so-called "spinless Salpeter equation," the
relativistic generalization of the nonrelativistic Schroedinger equation, is
used to describe both bound states of scalar particles and the spin-averaged
spectra of bound states of fermions. A numerical procedure solves the spinless
Salpeter equation by approximating this eigenvalue equation by a matrix
eigenvalue problem with explicitly known matrices.

</DOC>
<DOC>
<DOCNO> 68455 </DOCNO>
The Asymptotic Regime of High Density QCD


  We discuss the distinct approaches for high density QCD (hdQCD) in the
asymptotic regime of large values of parton density. We derive the AGL equation
for running coupling constant and obtain the asymptotic solution, demonstrating
that the property of partial saturation of the solution of the AGL equation is
not modified by the running of the coupling constant. We show that in this
kinematical regime, the solution of the AGL equation coincides with the
solution of an evolution equation, obtained recently using the
McLerran-Venugopalan approach. Using the asymptotic behavior of the gluon
distribution we calculate the $F_2$ structure function assuming first that the
leading twist relation between these two quantities is valid and second that
this relation is modified by the higher twist terms associated to the unitarity
corrections. In the first case we obtain that the corresponding $F_2$ structure
function is linearly proportional to $ln s$, which agrees with the results
obtained recently by Kovchegov using a distinct approach. In the second case a
softer behavior is obtained. In both cases, the $F_2$ structure function
unitarizes and the Froissart boundary is not violated in the asymptotic regime
of high density QCD. We conclude that the partial saturation of the gluon
distribution and the unitarization of the structure function are general
results, well-established by three distinct approaches for high dense systems.

</DOC>
<DOC>
<DOCNO> 70451 </DOCNO>
Lambda polarization from unpolarized quark fragmentation


  The longstanding problem of explaining the observed polarization of Lambda
hyperons inclusively produced in the high energy collisions of unpolarized
hadrons is tackled by considering spin and k_T dependent quark fragmentation
functions. The data on Lambda's and Lambda-bar's produced in p-N processes are
used to determine simple phenomenological expressions for these new "polarizing
fragmentation functions", which describe the experiments remarkably well.

</DOC>
<DOC>
<DOCNO> 84369 </DOCNO>
Naked Singularity Explosion


  It is known that the gravitational collapse of a dust ball results in naked
singularity formation from an initial density profile which is physically
reasonable. In this paper, we show that explosive radiation is emitted during
the formation process of the naked singularity.

</DOC>
<DOC>
<DOCNO> 68394 </DOCNO>
An estimate of higher twist at small x and low Q^2 based upon a


  We investigate the influence of higher twist corrections to deep inelastic
structure functions in the low-$Q^2$ and small-$x$ HERA region. We review the
general features of the lowest-order QCD diagrams which contribute to twist-4
at small-$x$, in particular the sign structure of longitudinal and transverse
structure functions which offers the possibility of strong cancellations in
$F_2$. For a numerical analysis we perform a twist analysis of the saturation
model which has been very successful both in describing the structure function
and the DIS diffractive cross section at HERA. As the main conclusion, twist 4
corrections are not small in $F_L$ or $F_T$ but in $F_2=F_L + F_T$ they almost
cancel. This indicates the limitation on the use of the DGLAP formalism at
small $x$ and $Q^2$. We point out that $F_L$ analysis needs a large twist-4
correction. We also indicate the region of validity of the twist expansion.

</DOC>
<DOC>
<DOCNO> 83097 </DOCNO>
Prospects for in-depth story understanding by computer


  While much research on the hard problem of in-depth story understanding by
computer was performed starting in the 1970s, interest shifted in the 1990s to
information extraction and word sense disambiguation. Now that a degree of
success has been achieved on these easier problems, I propose it is time to
return to in-depth story understanding. In this paper I examine the shift away
from story understanding, discuss some of the major problems in building a
story understanding system, present some possible solutions involving a set of
interacting understanding agents, and provide pointers to useful tools and
resources for building story understanding systems.

</DOC>
<DOC>
<DOCNO> 11720 </DOCNO>
Breakdown of universality in transitions to spatio-temporal chaos


  In this Letter we show that the transition from laminar to active behavior in
extended chaotic systems can vary from a continuous transition in the
universality class of Directed Percolation with infinitely many absorbing
states to what appears as a first order transition. The latter occurs when {\em
finite} lifetime non-chaotic structures, called ``solitons'', dominate the
dynamics. We illustrate this scenario in an extension of the deterministic
Chat\'e--Manneville coupled map lattice model and in a soliton including
variant of the stochastic Domany-Kinzel cellular automaton.

</DOC>
<DOC>
<DOCNO> 70597 </DOCNO>
NRQCD, Effective Field Theories and Potential Models


  We review some recent developments on non-relativistic effective field
theories for heavy quark-antiquark systems and how they can bring a well
founded connection between QCD and potential models.

</DOC>
<DOC>
<DOCNO> 102101 </DOCNO>
Characterization and computation of canonical tight windows for Gabor


  Let $(g_{nm})_{n,m\in Z}$ be a Gabor frame for $L_2(R)$ for given window $g$.
We show that the window $h^0=S^{-1/2} g$ that generates the canonically
associated tight Gabor frame minimizes $\|g-h\|$ among all windows $h$
generating a normalized tight Gabor frame. We present and prove versions of
this result in the time domain, the frequency domain, the time-frequency
domain, and the Zak transform domain, where in each domain the canonical $h^0$
is expressed using functional calculus for Gabor frame operators. Furthermore,
we derive a Wiener-Levy type theorem for rationally oversampled Gabor frames.
Finally, a Newton-type method for a fast numerical calculation of $\ho$ is
presented. We analyze the convergence behavior of this method and demonstrate
the efficiency of the proposed algorithm by some numerical examples.

</DOC>
<DOC>
<DOCNO> 69597 </DOCNO>
Field distributions in heavy mesons and baryons


  Field distributions generated by static quark-antiquark and QQQ sources are
calculated analytically in the framework of the Field Correlator Method (FCM)
using Gaussian (bilocal) correlator. In both cases the string consists mostly
of longitudinal color electric field, while transverse electric field
contributes locally less then 3%, in agreement with earlier lattice studies. In
the QQQ case the profile of the Y shape was calculated for the first time and
found to have a complicated structure with a deep well at the string junction
position. Possible consequences of this form for the baryon structure are
discussed.

</DOC>
<DOC>
<DOCNO> 7940 </DOCNO>
Non-Ohmic Coulomb drag in the ballistic electron transport regime


  We work out a theory of the Coulomb drag current created under the ballistic
transport regime in a one-dimensional nanowire by a ballistic non-Ohmic current
in a nearby parallel nanowire. As in the Ohmic case, we predict sharp
oscillation of the drag current as a function of gate voltage or the chemical
potential of electrons. We study also dependence of the drag current on the
voltage V across the driving wire. For relatively large values of V the drag
current is proportional to V^2.

</DOC>
<DOC>
<DOCNO> 178573 </DOCNO>
First order optical potentials and 25 to 40 MeV proton elastic


  The differential cross sections and analyzing powers from the elastic
scattering of 25 and 40 MeV protons from many nuclei have been studied.
Analyses have been made using a fully microscopic model of proton-nucleus
scattering seeking to establish a means appropriate for use in analyses of
radioactive beam scattering from hydrogen with ion energies 25A and 40A MeV.

</DOC>
<DOC>
<DOCNO> 101104 </DOCNO>
First order ODEs, Symmetries and Linear Transformations


  An algorithm for solving first order ODEs, by systematically determining
symmetries of the form [ xi = F(x), eta = P(x) y + Q(x) ], where xi d/dx + eta
d/dy is the symmetry generator - is presented. To these {\it linear} symmetries
one can associate an ODE class which embraces all first order ODEs mappable
into separable through linear transformations {t = f(x), u = p(x) y + q(x)}.
This single ODE class includes as members, for instance, 78% of the 552
solvable first order examples of Kamke's book. Concerning the solving of this
class, a restriction on the algorithm being presented exists only in the case
of Riccati type ODEs, for which linear symmetries {\it always} exist but the
algorithm will succeed in finding them only partially.

</DOC>
<DOC>
<DOCNO> 120048 </DOCNO>
Type Ia Supernova Explosion Models


  Because calibrated light curves of Type Ia supernovae have become a major
tool to determine the local expansion rate of the Universe and also its
geometrical structure, considerable attention has been given to models of these
events over the past couple of years. There are good reasons to believe that
perhaps most Type Ia supernovae are the explosions of white dwarfs that have
approached the Chandrasekhar mass, M_ch ~ 1.39 M_sun, and are disrupted by
thermonuclear fusion of carbon and oxygen. However, the mechanism whereby such
accreting carbon-oxygen white dwarfs explode continues to be uncertain. Recent
progress in modeling Type Ia supernovae as well as several of the still open
questions are addressed in this review. Although the main emphasis will be on
studies of the explosion mechanism itself and on the related physical
processes, including the physics of turbulent nuclear combustion in degenerate
stars, we also discuss observational constraints.

</DOC>
<DOC>
<DOCNO> 85439 </DOCNO>
Uniqueness of Simultaneity


  We consider the problem of uniqueness of certain simultaneity structures in
flat spacetime. Absolute simultaneity is specified to be a non-trivial
equivalence relation which is invariant under the automorphism group Aut of
spacetime. Aut is taken to be the identity-component of either the
inhomogeneous Galilei group or the inhomogeneous Lorentz group. Uniqueness of
standard simultaneity in the first, and absence of any absolute simultaneity in
the second case are demonstrated and related to certain group theoretic
properties. Relative simultaneity with respect to an additional structure X on
spacetime is specified to be a non-trivial equivalence relation which is
invariant under the subgroup in Aut that stabilises X. Uniqueness of standard
Einstein simultaneity is proven in the Lorentzian case when X is an inertial
frame. We end by discussing the relation to previous work of others.

</DOC>
<DOC>
<DOCNO> 12258 </DOCNO>
Relaxation in kinetic models on alternating linear chains


  A restricted dynamics, previously introduced in a kinetic model for
relaxation phenomena in linear polymer chains, is used to study the dynamic
critical exponent of one-dimensional Ising models. Both the alternating
isotopic chain and the alternating-bond chain are considered. In contrast with
what occurs for the Glauber dynamics, in these two models the dynamic critical
exponent turns out to be the same. The alternating isotopic chain with the
restricted dynamics is shown to lead to Nagel scaling for temperatures above
some critical value. Further support is given relating the Nagel scaling to the
existence of multiple (simultaneous) relaxation processes, the dynamics
apparently not playing the most important role in determining such scaling.

</DOC>
<DOC>
<DOCNO> 117809 </DOCNO>
Detection of the first X-ray selected large AGN group


  We have examined the spatial distribution of 856 AGN detected by the ROSAT
All-Sky Survey (RASS) using a direct search for structures with the minimal
spanning tree. The AGNs were compiled from an area of 7000 deg^2, in which
optical identifications of RASS sources were made with the help of the
digitized objective prism plates of the Hamburg Quasar Survey (HQS). Redshifts
were taken from the literature or from own follow-up observations. The sample
probes the spatial distribution at low redshifts, since the redshift
distribution peaks at z=0.1. The application of the minimal spanning tree led
to a 1.8 sigma discovery of an AGN group with 7 members in a volume V=140*75*75
h^-3Mpc^3 in the Pisces constellation. With a mean redshift z=0.27 this group
is only the third discovered group at redshifts z<0.5. The RASS offers
excellent possibilities to study large scale structure with AGNs at low
redshifts, once these redshifts are determined.

</DOC>
<DOC>
<DOCNO> 151138 </DOCNO>
Boundary State Description of Tachyon Condensation


  We construct the explicit boundary state description of the vortex-type
(codimension two) tachyon condensation in brane-antibrane systems generalizing
the known result of the kink-type (Frau et al. hep-th/9903123). In this
description we show how the RR-charge of the lower dimensional D-branes
emerges. We also investigate the tachyon condensation in T^4/Z_2 orbifold and
find that the twisted sector can be treated almost in the same way as the
untwisted sector from the viewpoint of the boundary state. Further we discuss
the higher codimension cases.

</DOC>
<DOC>
<DOCNO> 8325 </DOCNO>
Quantum oscillator as 1D anyon


  It is shown that in one spatial dimension the quantum oscillator is dual to
the charged particle situated in the field described by the superposition of
Coulomb and Calogero-Sutherland potentials.

</DOC>
<DOC>
<DOCNO> 152434 </DOCNO>
Dielectric branes and spontaneous symmetry breaking


  A stable non-commutative solution with symmetry breaking is presented for a
system of Dp-branes in the presence of a RR (p+5)-form.

</DOC>
<DOC>
<DOCNO> 151457 </DOCNO>
Conformal symmetry of superstrings on $AdS_3\times S^3\times T^4$ and


  Conformal field theory of the D1/D5 system and superstrings on $AdS_3\times
S^3\times T^4$ is studied with particular attention to the world-sheet fields
corresponding to the $T^4$ part. A solution to the spacetime N=4 superconformal
symmetry doubling and other problems is proposed. It is argued that the
relevant spacetime symmetry should be based on the middle N=4 superconformal
algebra. It is discussed as to why this superconformal structure has been
missed so far.

</DOC>
<DOC>
<DOCNO> 122978 </DOCNO>
The Evolution of Ellipticals, Spirals and Irregulars: Overcoming


  The Hubble Deep Fields represent our best opportunity for probing galaxy
evolution over a substantive look-back time. However as with any dataset the
HDFs are prone to selection biases. These biases are extremely severe beyond z
\~ 1.25 such that a meaningful interpretation of generic galaxy evolution is not
possible. We can however extract well defined volume-limited samples at z < 1.
The data are entirely consistent with passive/null-evolution for ellipticals,
spirals and irregulars however this concluion is tempered by small number
statistics. Alas stringent constraints on galaxy evolution await an order of
magnitude increase in the number of HDFs.

</DOC>
<DOC>
<DOCNO> 40297 </DOCNO>
Design and Construction of the 3.2 Mev Cathode Assembly for Darht II


  A 3.2 MeV injector has been designed and built for the Darht II Project at
Los Alamos Lab. The installation of the complete injector system is nearing
completion at this time. The requirements for the injector are to produce a 3.2
MeV, 2000 ampere electron pulse with a flattop width of at least 2-microseconds
and emittance of less than 0.15 p cm-rad normalized. A 16.5 cm diameter hot
emitter cathode is used. This paper will describe the design and fabrication of
major Cathode Assembly components and test performance of subsystems to date.
Mechanical and thermal issues will be emphasized. More detailed discussion of
the active alignment system used to maintain the stringent cathode alignment
requirement.

</DOC>
<DOC>
<DOCNO> 9460 </DOCNO>
Kondo effect in an integer-spin quantum dot


  The Kondo effect is a key many-body phenomenon in condensed matter physics.
It concerns the interaction between a localised spin and free electrons.
Discovered in metals containing small amounts of magnetic impurities, it is now
a fundamental mechanism in a wide class of correlated electron systems. Control
over single, localised spins has become relevant also in fabricated structures
due to the rapid developments in nano-electronics. Experiments have already
demonstrated artificial realisations of isolated magnetic impurities at
metallic surfaces, nanometer-scale magnets, controlled transitions between
two-electron singlet and triplet states, and a tunable Kondo effect in
semiconductor quantum dots. Here, we report an unexpected Kondo effect realised
in a few-electron quantum dot containing singlet and triplet spin states whose
energy difference can be tuned with a magnetic field. This effect occurs for an
even number of electrons at the degeneracy between singlet and triplet states.
The characteristic energy scale is found to be much larger than for the
ordinary spin-1/2 case.

</DOC>
<DOC>
<DOCNO> 121095 </DOCNO>
Mapping the peculiar binary GP Com


  We present high resolution spectra of the AM CVn helium binary GP Com at two
different wavelength ranges. The spectra show the same flaring behaviour
observed in previous UV and optical data. We find that the central spike
contributes to the flare spectra indicating that its origin is probably the
compact object. We also detect that the central spike moves with orbital phase
following an S-wave pattern. The radial velocity semiamplitude of the S-wave is
\~10 km/s which indicates its origin is near the centre of mass of the system,
which in this case lies very close to the white dwarf. The Stark effect seems
to affect significantly the central spike of some of the lines suggesting that
it forms in a high electron density region. This again favours the idea that
the central spike originates in the white dwarf. We present Doppler maps
obtained for the emission lines which show three clear emission regions.

</DOC>
<DOC>
<DOCNO> 13851 </DOCNO>
Electrons on a sphere in disorder potential


  We investigate, both analytically and numerically, the behavior of the
electron gas on a sphere in the presence of point-like impurities. We find a
criterion when the disorder can be regarded as small one and the main effect is
the broadening of rotational multiplets. In the latter regime the statistics of
one impurity-induced band is studied numerically. The energy level spacing
distribution function follows the law P(s) ~ s exp(-a s^b) with 1<b<2. The
number variance shows various possibilities, strongly dependent on the chosen
model of disorder.

</DOC>
<DOC>
<DOCNO> 100362 </DOCNO>
On the Asymptotics of Takeuchi Numbers


  I present an asymptotic formula for the Takeuchi numbers $T_n$. In
particular, I give compelling numerical evidence and present a heuristic
argument showing that $$T_n\sim C_T B_n\exp{1\over2}{W(n)}^2$$as $n$ tends to
infinity, where $B_n$ are the Bell numbers, W(n) is Lambert's $W$ function, and
$C_T=2.239...$ is a constant. Moreover, I show that the method presented here
can be generalized to derive conjectures for related problems.

</DOC>
<DOC>
<DOCNO> 69323 </DOCNO>
Softly Broken Supersymmetric Gauge-Higgs-Yukawa Theories as


  We examine the (softly broken) supersymmetric gauge-Higgs-Yukawa theories
satisfying the compositeness conditions at a certain scale. In these theories
the Higgs superfields can be regarded as the chiral composite fields. It is
found that there are the fundamental theories, which contain the dimension 5
interactions and the hard SUSY breaking in perturbation, turn to be
renormalizable and also softly broken theories in the nonperturbative
framework. The soft SUSY breaking parameters as well as the Yukawa coupling in
the corresponding gauge-Higgs-Yukawa theories are restricted by the
renormalization group invariant relations.

</DOC>
<DOC>
<DOCNO> 118274 </DOCNO>
The host galaxies of luminous radio-quiet quasars


  We present the results of a deep K-band imaging study which reveals the host
galaxies around a sample of luminous radio-quiet quasars. The K-band images,
obtained at UKIRT, are of sufficient quality to allow accurate modelling of the
underlying host galaxy. Initially, the basic structure of the hosts is revealed
using a modified Clean deconvolution routine optimised for this analysis. 2 of
the 14 quasars are shown to have host galaxies with violently disturbed
morphologies which cannot be modelled by smooth elliptical profiles. For the
remainder of our sample, 2D models of the host and nuclear component are fitted
to the images using the chi-squared statistic to determine goodness of fit.
Host galaxies are detected around all of the quasars. The reliability of the
modelling is extensively tested, and we find the host luminosity to be well
constrained for 9 quasars. The derived average K-band absolute K-corrected host
galaxy magnitude for these luminous radio-quiet quasars is <M_K>=-25.15+/-0.04,
slightly more luminous than an L* galaxy. The spread of derived host galaxy
luminosities is small, although the spread of nuclear-to-host ratios is not.
These host luminosities are shown to be comparable to those derived from
samples of quasars of lower total luminosity and we conclude that there is no
correlation between host and nuclear luminosity for these quasars.
Nuclear-to-host ratios break the lower limit previously suggested from studies
of lower nuclear luminosity quasars and Seyfert galaxies. Morphologies are less
certain but, on the scales probed by these images, some hosts appear to be
dominated by spheroids but others appear to have disk-dominated profiles.

</DOC>
<DOC>
<DOCNO> 10824 </DOCNO>
Spin-splitting in GaAs 2D holes


  We present quantitative measurements and calculations of the spin-orbit
induced zero-magnetic-field spin-splitting in two-dimensional (2D) hole systems
in modulation-doped GaAs (311)A quantum wells. The results show that the
splitting is large and tunable. In particular, via a combination of back- and
front-gate biases, we can tune the splitting while keeping the 2D hole density
constant. The data also reveal a surprising result regarding the
magnetoresistance (Shubnikov-de Haas) oscillations in a 2D system with
spin-split energy bands: the frequencies of the oscillations are {\it not}
simply related to the population of the spin-subbands. Next we concentrate on
the metallic-like behavior observed in these 2D holes and its relation to
spin-splitting. The data indicate that the metallic behavior is more pronounced
when two spin-subbands with unequal populations are occupied. Our measurements
of the magnetoresistance of these 2D hole systems with an in-plane magnetic
field corroborate this conclusion: while the system is metallic at zero
magnetic field, it turns insulating when one of the spin-subbands is
depopulated at high magnetic field.

</DOC>
<DOC>
<DOCNO> 8882 </DOCNO>
The system with exponentially degenerate vacuum state


  I suggest and examine artificial material which has exponentially degenerate
vacuum state. The corresponding Hamiltonian contains only exotic four-spin
interaction term. Each vacuum state is realized as a particular spin
configuration separated from others by potential barriers. The benefit of such
system in practical applications is that it can be used as high density
magnetic recording system which can reduce storage of one bit information to
$nm$ scale. The information is stored as a particular vacuum state of the
system. The process of recording can be visualized as a process in which the
system moves from one vacuum state to another. Storing information in the form
of different vacuum states separated by potential barriers will allow to
protect it from fluctuations and for a longer time. These materials can be
realized as lattices of nuclear spins with specially adjusted interactions. The
planes of flipped spins can in principle be of atomic scale.

</DOC>
<DOC>
<DOCNO> 102637 </DOCNO>
Integration on Lie supergroups. A Hopf superalgebra approach


  For a large class of finite-dimensional Lie superalgebras (including the
classical simple ones) a Lie supergroup associated to the algebra is defined by
fixing the Hopf superalgebra of functions on the supergroup. Then it is shown
that on this Hopf superalgebra there exists a non-zero left integral. According
to a recent work by the authors, this integral is unique up to scalar
multiples.

</DOC>
<DOC>
<DOCNO> 84995 </DOCNO>
An inquiry into the nature of the gamma-ray source 3EG J1828+0142


  The unidentified, low-latitude, $\gamma$-ray source 3EG J1828+0142 presents
high levels of variability and a steep spectral index $\Gamma\sim2.7$. Here we
propose a model for this source where the high-energy emission is produced by a
galactic Kerr-Newman black hole. The model takes into account electron-positron
annihilation losses in the calculation of the expected spectral energy
distribution and can reproduce the observational features, including the
absence of a strong radio counterpart. We also report the discovery of a nearby
supernova remnant that could be associated with the original supernova
explosion that created the black hole. Several faint radio sources were also
detected in the radio field within the inner $\gamma$-ray confidence contour
and their spectral index estimated. Some of these sources could be the expected
weak radio counterpart.

</DOC>
<DOC>
<DOCNO> 40413 </DOCNO>
The experimental future of Neutrino Oscillations


  After the recent experimental results on neutrino oscillations, some shape
starts to emerge from the puzzle. However, the situation is still far from
being clarified. First of all, accommodating all experimental results in a
single and simple framework is not possible, and the possibility of sterile
neutrinos entering the oscillation process has not been ruled out. Moreover,
new questions arise that the presently-available data, nor those that will be
available in a near future, will be able to answer. In this paper some of these
problems will be discussed, as well as the experimental guidelines for their
clarification.

</DOC>
<DOC>
<DOCNO> 118213 </DOCNO>
Temporal and Spectral Variabilities of High Energy Emission from Blazars


  Multiwavelength observations of blazars such as Mrk 421 and Mrk 501 show that
they exhibit strong short time variabilities in flare-like phenomena. Based on
the homogeneous synchrotron self-Compton (SSC) model and assuming that time
variability of the emission is initiated by changes in the injection of
nonthermal electrons, we perform detailed temporal and spectral studies of a
purely cooling plasma system. One important parameter is the total injected
energy E and we show how the synchrotron and Compton components respond as E
varies. We discuss in detail how one could infer important physical parameters
using the observed spectra. In particular, we could infer the size of the
emission region by looking for exponential decay in the light curves. We could
also test the basic assumption of SSC by measuring the difference in the rate
of peak energy changes of synchrotron and SSC peaks. We also show that the
trajectory in the photon-index and flux plane evolves clockwise or
counter-clockwise depending on the value of E and observed energy bands.

</DOC>
<DOC>
<DOCNO> 151080 </DOCNO>
D-branes as Tachyon Lumps in String Field Theory


  It has been conjectured that the tachyonic lump solution of the open bosonic
string field theory describing a D-brane represents a D-brane of one lower
dimension. We place the lump on a circle of finite radius and develop a variant
of the level expansion scheme that allows systematic account of all higher
derivative terms in the string field theory action, and gives a calculational
scheme that can be carried to arbitrary accuracy. Using this approach we obtain
lump masses that agree with expected D-brane masses to an accuracy of about 1%.
We find convincing evidence that in string field theory the lump representing a
D-brane is an extended object with a definite profile. A gaussian fit to the
lump gives a 6-sigma size of 9.3 \sqrt{\alpha'}. The level truncation scheme
developed here naturally gives rise to an infrared and ultraviolet cut-off, and
may be useful in the study of quantum string field theory.

</DOC>
<DOC>
<DOCNO> 14029 </DOCNO>
Triggered single photons from a quantum dot


  We demonstrate a new method for generating triggered single photons. After a
laser pulse generates excitons inside of a single quantum dot, electrostatic
interactions between them and the resulting spectral shifts allow a single
emitted photon to be isolated. Autocorrelation measurements show a reduction of
the two-photon probability to 0.12 times the value for Poisson light. Strong
anti-bunching persists when the emission is saturated. The emitted photons are
also polarized.

</DOC>
<DOC>
<DOCNO> 118837 </DOCNO>
HST/STIS Ultraviolet Imaging of Polar Aurora on Ganymede


  We report new observations of the spectrum of Ganymede in the spectral range
1160 - 1720 A made with the Space Telescope Imaging Spectrograph (STIS) on HST
on 1998 October 30. The observations were undertaken to locate the regions of
the atomic oxygen emissions at 1304 and 1356 A, previously observed with the
GHRS on HST, that Hall et al. (1998) claimed indicated the presence of polar
aurorae on Ganymede. The use of the 2" wide STIS slit, slightly wider than the
disk diameter of Ganymede, produced objective spectra with images of the two
oxygen emissions clearly separated. The OI emissions appear in both
hemispheres, at latitudes above 40 degrees, in accordance with recent Galileo
magnetometer data that indicate the presence of an intrinsic magnetic field
such that Jovian magnetic field lines are linked to the surface of Ganymede
only at high latitudes. Both the brightness and relative north-south intensity
of the emissions varied considerably over the four contiguous orbits (5.5
hours) of observation, presumably due to the changing Jovian plasma environment
at Ganymede. However, the observed longitudinal non-uniformity in the emission
brightness at high latitudes, particularly in the southern hemisphere, and the
lack of pronounced limb brightening near the poles are difficult to understand
with current models. In addition to observed solar HI Lyman-alpha reflected
from the disk, extended Lyman-alpha emission resonantly scattered from a
hydrogen exosphere is detected out to beyond two Ganymede radii from the limb,
and its brightness is consistent with the Galileo UVS measurements of Barth et
al. (1997).

</DOC>
<DOC>
<DOCNO> 116953 </DOCNO>
Generalized Relativistic Effective Core Potential Method: Theory and


  In calculations of heavy-atom molecules with the shape-consistent
Relativistic Effective Core Potential (RECP), only valence and some outer-core
shells are treated explicitly, the shapes of spinors are smoothed in the atomic
core regions and the small components of four-component spinors are excluded
from calculations. Therefore, the computational efforts can be dramatically
reduced.
  However, in the framework of the standard nodeless radially local RECP
versions, any attempt to extend the space of explicitly treated electrons more
than some limit does not improve the accuracy of the calculations. The errors
caused by these (nodeless) RECPs can range up to 2000 $cm^{-1}$ and more for
the dissociation and transition energies even for lowest-lying excitations that
can be unsatisfactory for many applications. Moreover, the direct calculation
of such properties as electronic densities near heavy nuclei, hyperfine
structure, and matrix elements of other operators singular on heavy nuclei is
impossible as a result of the smoothing of the orbitals in the core regions.
  In the present paper, ways to overcome these disadvantages of the RECP method
are discussed. The developments of the RECP method suggested by the authors are
studied in many precise calculations of atoms and of the TlH, HgH molecules.
The technique of nonvariational restoration of electronic structure in cores of
heavy atoms in molecules is applied to calculation of the P,T-odd
spin-rotational Hamiltonian parameters including the weak interaction terms
which break the symmetry over the space inversion (P) and time-reversal
invariance (T) in the PbF, HgF, BaF, and YbF molecules.

</DOC>
<DOC>
<DOCNO> 8622 </DOCNO>
Ballistic electron transport in stubbed quantum waveguides: experiment


  We present results of experimental and theoretical investigations of electron
transport through stub-shaped waveguides or electron stub tuners (ESTs) in the
ballistic regime. Measurements of the conductance G as a function of voltages,
applied to different gates V_i (i=bottom, top, and side) of the device, show
oscillations in the region of the first quantized plateau which we attribute to
reflection resonances. The oscillations are rather regular and almost periodic
when the height h of the EST cavity is small compared to its width. When h is
increased, the oscillations become less regular and broad depressions in G
appear. A theoretical analysis, which accounts for the electrostatic potential
formed by the gates in the cavity region, and a numerical computation of the
transmission probabilities successfully explains the experimental observations.
An important finding for real devices, defined by surface Schottky gates, is
that the resonance nima result from size quantization along the transport
direction of the EST.

</DOC>
<DOC>
<DOCNO> 101031 </DOCNO>
A Rational Surgery Formula for the LMO Invariant


  We write a formula for the LMO invariant of a rational homology sphere
presented as a rational surgery on a link in S^3. Our main tool is a careful
use of the Aarhus integral and the (now proven) "Wheels" and "Wheeling"
conjectures of B-N, Garoufalidis, Rozansky and Thurston. As steps, side
benefits and asides we give explicit formulas for the values of the Kontsevich
integral on the Hopf link and on Hopf chains, and for the LMO invariant of lens
spaces and Seifert fibered spaces. We find that the LMO invariant does not
separate lens spaces, is far from separating general Seifert fibered spaces,
but does separate Seifert fibered spaces which are integral homology spheres.

</DOC>
<DOC>
<DOCNO> 120124 </DOCNO>
The angular power spectra of polarized Galactic synchrotron


  We derive the angular power spectra of intensity and polarization of Galactic
synchrotron emission in the range 36 < l < 10^3 from the Parkes survey mapping
the southern Galactic plane at 2.4 GHz. The polarization spectra of both
electric and magnetic parity up to l \simeq 10^3 are approximated very well by
power laws with slope coefficients \simeq 1.4, quite different from the CMB
spectra. We show that no problem should arise from Galactic synchrotron for
measurements of CMB polarization in the cosmological window.

</DOC>
<DOC>
<DOCNO> 118920 </DOCNO>
III Zw 2, the first superluminal jet in a Seyfert galaxy


  So far all relativistically boosted jets with superluminal motion have only
been detected in typical radio galaxies with early type host galaxies. We have
now discovered superluminal motion in the Seyfert I galaxy III Zw 2, classified
as a spiral. Superluminal motion was first inferred from the spectral evolution
of the source and then confirmed by VLBI observations. The lower limit for the
apparent expansion speed is 1.25 +/- 0.09 c. The fact that the spectral and
spatial evolution are closely linked demonstrates that we are dealing with real
physical expansion. Prior to this rapid expansion we have seen a period of
virtually no expansion with an expansion speed less than 0.04 c. Since III Zw 2
is also part of a sample of so called radio-intermediate quasars (RIQ), it
confirms earlier predictions of superluminal motion for this source, based on
the argument that RIQs could be relativistically boosted jets in radio-weak
quasars and Seyfert galaxies.

</DOC>
<DOC>
<DOCNO> 70194 </DOCNO>
Energy Dependence of \sigma^{DD}/\sigma_{tot} in DIS and Shadowing


  We gereralize the Kochegov-McLerran formula for the ratio
$\sigma^{DD}/\sigma_{tot}$ in perturbative QCD, using Mueller-Glauber approach
for shadowing corrections and AGK cutting rules. We investigate several
phenomenological approaches with the goal of obtaining results consisent with
experimental data. We fail to reproduce the observed weak energy dependence of
the ratio, and conclude that the soft nonperturbative contribution present at
short distances must also be included.

</DOC>
<DOC>
<DOCNO> 12114 </DOCNO>
Persistence distributions for non gaussian markovian processes


  We propose a systematic method to derive the asymptotic behaviour of the
persistence distribution, for a large class of stochastic processes described
by a general Fokker-Planck equation in one dimension. Theoretical predictions
are compared to simple solvable systems and to numerical calculations. The very
good agreement attests the validity of this approach.

</DOC>
<DOC>
<DOCNO> 101580 </DOCNO>
Berezin-Toeplitz quantization and Berezin transform


  In this lecture results on the Berezin-Toeplitz quantization of arbitrary
compact quantizable Kaehler manifolds are presented.
 These results are obtained in joint work with M. Bordemann and E. Meinrenken.
The existence of the Berezin-Toeplitz deformation quantization is also covered.
Recent results obtained in joint work with A. Karabegov on the asymptotic
expansion of the Berezin transform for arbitrary quantizable compact Kaehler
manifolds are explained. As an application the asymptotic expansion of the
Fubini-Study fundamental form under the coherent state embedding is considered.
Some comments on the dynamics of the quantum operators are given. (This is an
extended write-up of an invited lecture presented at the workshop ``Asymptotic
properties of time evolutions in classical and quantum systems'', September
13-17, 1999, Bologna, Italy.)

</DOC>
<DOC>
<DOCNO> 150363 </DOCNO>
Lifshitz Phase Gauge Symmetry Breaking and Application to $E_6$ and


  This paper has been withdrawn, because the argument for generating Goldstone
modes at a Lifshitz point is incorrect.

</DOC>
<DOC>
<DOCNO> 71922 </DOCNO>
V-A hadronic tau decays : a QCD laboratory


  Recent ALEPH/OPAL data on the V-A spectral functions from hadronic tau decays
are used for fixing the QCD continuum threshold at which the first and second
Weinberg sum rules should be satisfied in the chiral limit, and for predicting
the values of the low-energy constants f_\pi,~m_{\pi^+}-m_{\pi^0} and {L}_{10}.
Some DMO-like sum rules and the $\tau$-total hadronic widths R_{\tau,V-A} are
also used for extracting the values of the D=6,~8 QCD vacuum condensates and
the corresponding (in the chiral limit) electroweak kaon penguin matrix
elements Q^{3/2}_{8,7}\ra_{2\pi},, where a deviation from the vacuum saturation
estimate has been obtained. Combining these results with the one of the QCD
penguin matrix element Q^{1/2}_{6}\ra_{2\pi} obtained from a (maximal) \bar
qq-gluonium mixing scheme from the scalar meson sum rules, we deduce, in the
Electroweak Standard Model (ESM), the conservative upper bound for the
CP-violating ratio: \epsilon'/\epsilon \leq (22\pm 9) 10^{-4}, in agreement
with the present measurements.

</DOC>
<DOC>
<DOCNO> 8194 </DOCNO>
On slip pulses at a sheared frictional viscoelastic/ non deformable


  We study the possibility for a semi-infinite block of linear viscoelastic
material, in homogeneous frictional contact with a non-deformable one, to slide
under shear via a periodic set of ``self-healing pulses'', i.e. a set of
drifting slip regions separated by stick ones. We show that, contrary to
existing experimental indications, such a mode of frictional sliding is
impossible for an interface obeying a simple local Coulomb law of solid
friction. We then discuss possible physical improvements of the friction model
which might open the possibility of such dynamics, among which slip weakening
of the friction coefficient, and stress the interest of developing systematic
experimental investigations of this question.

</DOC>
<DOC>
<DOCNO> 119543 </DOCNO>
Abundance evolution of intermediate mass elements (C to Zn) in the Milky


  We present a comprehensive study of the evolution of the abundances of
intermediate mass elements, from C to Zn, in the Milky Way halo and in the
local disk. We use a consistent model to describe the evolution of those two
galactic subsystems. The halo and the disk are assumed to evolve independently,
both starting with gas of primordial composition, and in different ways: strong
outflow is assumed to take place during the $\sim$1 Gyr of the halo formation,
while the disk is built by slowly infalling gas. This description of the
halo+disk evolution can correctly account for the main observational
constraints (at least in the framework of simple models of galactic chemical
evolution). We utilise then metallicity dependant yields to study the evolution
of all elements from C and Zn. Comparing our results to an extensive body of
observational data (including very recent ones), we are able to make a critical
analysis of the successes and shortcomings of current yields of massive stars.
Finally, we discuss qualitatively some possible ways to interpret the recent
data on oxygen vs iron, which suggest that oxygen behaves differently from the
other alpha-elements.

</DOC>
<DOC>
<DOCNO> 85058 </DOCNO>
Angular Momentum in Loop Quantum Gravity


  An angular momentum operator in loop quantum gravity is defined using
spherically symmetric states as a non-rotating reference system. It can be
diagonalized simultaneously with the area operator and has the familiar
spectrum. The operator indicates how the quantum geometry of non-rotating
isolated horizons can be generalized to rotating ones and how the recent
computations of black hole entropy can be extended to rotating black holes.

</DOC>
<DOC>
<DOCNO> 121670 </DOCNO>
The Contribution of EUV from Clusters of Galaxies to the Cosmic Ionizing


  Recent observations with the Extreme Ultraviolet Explorer (EUVE) suggest that
at least some clusters of galaxies are luminous sources of extreme ultraviolet
(EUV) radiation. It is not clear yet whether EUV emission is a general feature
of clusters; for the purposes of limiting the contribution to the background
radiation, we assume that it is true of most clusters. Assuming that the source
of the EUV emission is inverse Compton (IC) scattering of the Cosmic Microwave
Background photons by relativistic electrons, we construct a simple model for
the expected average emission from clusters as a function of their mass and the
redshift of interest. Press-Schechter theory is used to determine the abundance
of clusters of various masses as a function of redshift. We determine the
amount of background radiation produced by clusters. The total mean intensity,
spectrum, and the ionization rates for HI and HeII are determined at present
and at a variety of redshifts. Because clusters form by the merger of smaller
subclusters, the amount of EUV background radiation should be larger at present
than in the past. We compare our results to the ionizing background expected
from quasars. We find that while clusters do contribute a significant EUV
background, it is less than a percent of that expected from quasars.

</DOC>
<DOC>
<DOCNO> 116765 </DOCNO>
The Explanation of the New Astronomical Distance Data That has Resulted


  Recently it has become possible to determine the distance to Type Ia
supernovae by redshift-independent means. Those new distance determinations
exceed the Hubble distance by 10 - 15%. The explanation others propose is that
an "antigravity effect" is accelerating the universe' expansion, which had
hitherto been thought to be slowing down because of gravitation. That has led
to their proposing reinstatement of Einstein's "cosmological constant", a term
in his equations introduced to account for gravitation not promptly collapsing
the universe and which he disavowed upon Hubble's discovery of the expansion of
the universe. And that has further led to their proposing some form of the
Ancients' fifth essence, quintessence [the first four being earth, air, fire
and water], to account for the "antigravity effect".
     Any "antigravity effect", regardless of its cause, would have the effect
of counteracting ordinary gravitation. Inasmuch as one of the major current
problems in cosmology is to identify more gravitation to account for the
cosmos's large scale structure and galaxies' centrifugal force, any
"antigravity effect" to act as the cause of accelerating expansion would not
appear to fit with the rest of the cosmological situation.
     An alternative explanation is presented -- the general exponential decay
of the overall universe, which has been analyzed and developed in several
papers. The universal decay accounts for the greater distances and the
necessary cosmic energy without the challenge to theory and to reasonableness
that acceleration, its unknown cause, and a cosmological constant involve.

</DOC>
<DOC>
<DOCNO> 8373 </DOCNO>
Phase Transition in a Traffic Model with Passing


  We investigate a traffic model in which cars either move freely with quenched
intrinsic velocities or belong to clusters formed behind slower cars. In each
cluster, the next-to-leading car is allowed to pass and resume free motion. The
model undergoes a phase transition from a disordered phase for the high passing
rate to a jammed phase for the low rate. In the disordered phase, the cluster
size distribution decays exponentially in the large size limit. In the jammed
phase, the cluster size distribution has a power law tail and in addition there
is an infinite-size cluster. Mean-field equations, describing the model in the
framework of Maxwell approximation, correctly predict the existence of phase
transition and adequately describe the disordered phase; properties of the
jammed phase are studied numerically.

</DOC>
<DOC>
<DOCNO> 9536 </DOCNO>
Reply to Comment on "Triviality of the Ground State Structure in Ising


  We reply to the comment of Marinari and Parisi [cond-mat/0002457 v2] on our
paper [Phys. Rev. Lett. 83, 5126 (1999) and cond-mat/9906323]. We show that the
data in the comment are affected by strong finite-size corrections. Therefore
the original conclusion of our paper still stands.

</DOC>
<DOC>
<DOCNO> 72234 </DOCNO>
A local Langevin equation for slow long-distance modes of hot


  The effective theory for the dynamics of hot non-Abelian gauge fields with
spatial momenta of order of the magnetic screening scale g^2 T is described by
a Boltzmann equation. The dynamical content of this theory is explored. There
are three relevant frequency scales, g T, g^2 T and g^4 T, associated with
plasmon oscillations, multipole fluctuations of color charge, and with the
non-perturbative gauge field dynamics, respectively. The frequency scale g T is
integrated out. The result is a local Langevin-type equation. It is valid to
leading order in g and to all orders in log(1/g), and it does not suffer from
the hard thermal loop divergences of classical thermal Yang-Mills theory. We
then derive the corresponding Fokker-Planck equation, which is shown to
generate an equilibrium distribution corresponding to 3-dimensional Yang-Mills
theory plus a Gaussian free field.

</DOC>
<DOC>
<DOCNO> 69018 </DOCNO>
Tau neutrinos from muon storage rings


  Charged tau leptons emerging in a long baseline experiment with a muon
storage ring and a far-away detector will positively establish neutrino
oscillations. We study the conversion of $\nu_\mu$ ($\bar{\nu}_\mu$) and of
$\bar{\nu}_e$ ($\nu_e$) to $\nu_\tau$ or $\bar{\nu}_\tau$ for neutrinos from a
20 GeV muon storage ring, within the strong mixing scheme and on the basis of
the squared mass differences which are compatible with all reported neutrino
anomalies, including the LSND data. In contrast to other solutions which ignore
the Los Alamos anomaly, we find charged tau production rates which should be
measurable in a realistic set up. As a consequence, determining the complete
mass spectrum of neutrinos as well as all three mixing angles seems within
reach. Matter effects are discussed thoroughly but are found to be small in
this situation.

</DOC>
<DOC>
<DOCNO> 117192 </DOCNO>
Nanosecond dynamics of a gallium mirror's light-induced reflectivity


  Transient pump-probe optical reflectivity measurements of the
nano/microsecond dynamics of a fully reversible, light-induced,
surface-assisted metallization of gallium interfaced with silica are reported.
The metallization leads to a considerable increase in the interface's
reflectivity when solid a-gallium is on the verge of melting. The reflectivity
change was found to be a cumulative effect that grows with light intensity and
pulse duration. The reflectivity relaxes back to that of alpha-gallium when the
excitation is withdrawn in a time that increases critically at gallium's
melting point. The effect is attributed to a non-thermal light-induced
structural phase transition.

</DOC>
<DOC>
<DOCNO> 122753 </DOCNO>
Measuring Stellar and Dark Mass Fractions in Spiral Galaxies


  We explore the relative importance of the stellar mass density as compared to
the inner dark halo, for the observed gas kinematics thoughout the disks of
spiral galaxies. We perform hydrodynamical simulations of the gas flow in a
sequence of potentials with varying the stellar contribution to the total
potential. The stellar portion of the potential was derived empirically from
K-band photometry. The output of the simulations - namely the gas density and
the gas velocity field - are then compared to the observed spiral arm
morphology and the H-alpha gas kinematics. We solve for the best matching
spiral pattern speed and draw conclusions on how massive the stellar disk can
be at most. For the case of the galaxy NGC 4254 (Messier 99) we demonstrate
that the prominent spiral arms of the stellar component would overpredict the
non-circular gas motions unless an axisymmetric dark halo component adds
significantly in the radial range R_exp < R < 3*R_exp.

</DOC>
<DOC>
<DOCNO> 9903 </DOCNO>
Signature of wave localisation in the time dependence of a reflected


  The average power spectrum of a pulse reflected by a disordered medium
embedded in an N-mode waveguide decays in time with a power law t^(-p). We show
that the exponent p increases from 3/2 to 2 after N^2 scattering times, due to
the onset of localisation. We compare two methods to arrive at this result. The
first method involves the analytic continuation to imaginary absorption rate of
a static scattering problem. The second method involves the solution of a
Fokker-Planck equation for the frequency dependent reflection matrix, by means
of a mapping onto a problem in non-Hermitian quantum mechanics.

</DOC>
<DOC>
<DOCNO> 122369 </DOCNO>
Near-infrared line imaging of the starburst galaxies NGC 520, NGC 1614


  We present high spatial resolution (0.6 arcsec) near-infrared broad-band JHK
images and Br_gamma 2.1661 micron and H_2 1-0 S(1) 2.122 micron emission line
images of the nuclear regions in the interacting starburst galaxies NGC 520,
NGC 1614 and NGC 7714. The near-infrared emission line and radio morphologies
are in general agreement, although there are differences in details. In NGC
1614, we detect a nuclear double structure in Br_gamma, in agreement with the
radio double structure. We derive average extinctions of A(K) = 0.41 and A(K) =
0.18 toward the nuclear regions of NGC 1614 and NGC 7714, respectively. For NGC
520, the extinction is much higher, A(K) = 1.2 - 1.6. The observed H_2/Br_gamma
ratios indicate that the main excitation mechanism of the molecular gas is
fluorescence by intense UV radiation from clusters of hot young stars, while
shock excitation can be ruled out.
  The starburst regions in all galaxies exhibit small Br_gamma equivalent
widths. Assuming a constant star formation model, even with a lowered upper
mass cutoff of M_u = 30 M_o, results in rather old ages (10 - 40 Myr), in
disagreement with the clumpy near-infrared morphologies. We prefer a model of
an instantaneous burst of star formation with M_u = 100 M_o, occurring 6 - 7
Myr ago, in agreement with previous determinations and with the detection of
W-R features in NGC 1614 and NGC 7714. Finally, we note a possible systematic
difference in the amount of hot molecular gas between starburst and Seyfert
galaxies.

</DOC>
<DOC>
<DOCNO> 71671 </DOCNO>
Radiative B Decays at CLEO


  We report on the status of a variety of radiative B decays studied by the
CLEO detector with $9.7\times 10^6$ $B\bar{B}$ pairs.

</DOC>
<DOC>
<DOCNO> 8415 </DOCNO>
Density functional theory of phase coexistence in weakly polydisperse


  The recently proposed universal relations between the moments of the
polydispersity distributions of a phase-separated weakly polydisperse system
are analyzed in detail using the numerical results obtained by solving a simple
density functional theory of a polydisperse fluid. It is shown that universal
properties are the exception rather than the rule.

</DOC>
<DOC>
<DOCNO> 121986 </DOCNO>
Resonant Gaps in the Scattered Cometary Population of the


  Our numerical simulations of the Edgeworth-Kuiper belt objects
gravitationally scattered by the four giant planets accounting for mean motion
resonances reveal numerous resonant gaps in the distribution of the scattered
population.

</DOC>
<DOC>
<DOCNO> 70996 </DOCNO>
$B \to K\pi$ decays and the weak phase angle $\gamma$


  The large branching ratios for $B \to K\pi$ decays as observed by the CLEO
Collaboration indicate that penguin interactions contribute a major part to the
decay rates and provide an interference between the Cabibbo-suppressed tree and
penguin contributions resulting in a CP-asymmetry between the $B \to K\pi$ and
its charge conjugate mode. The CP-averaged decay rates depend also on the weak
phase $\gamma$ and give us a determination of this phase. In this talk, I would
like to report on a recent analysis of $B \to K\pi$ decays using factorisation
model with final state interaction phase shift included. We find that
factorisation seems to describe qualitatively the latest CLEO data. We also
obtain a relation for the branching ratios independent of the strength of the
strong penguin interactions. This relation gives a central value of $0.60
\times 10^{-5}$ for ${\mathcal B}(\bar{B}^{0} \to \bar{K}^{0}\pi^{0})$,
somewhat smaller than the latest CLEO measurement. We also find that a ratio
obtained from the CP-averaged $B \to K\pi$ decay rates could be used to test
the factorisation model and to determine the weak angle $\gamma$ with more
precise data, though the latest CLEO data seem to favor $\gamma$ in the range
$90^{\circ}-120^{\circ}$.

</DOC>
<DOC>
<DOCNO> 150377 </DOCNO>
Gravitating (bi-)sphalerons


  The standard model of electroweak interactions is minimally coupled to
gravity and the response of the spherically symmetric solutions -the sphaleron
and the bisphaleron- to gravity is emphasized. For a given value of the Higgs
mass $M_H$, several branches of solutions exist which terminate into
cusp-catastrophy at some ($M_H$-depending) critical value of the parameter
$\alpha$ defined by the ratio of the vector-boson mass to the Planck mass. A
given branch either bifurcates from another one at an intermediate value of
$\alpha$ or persists in the limit $\alpha \to 0$ where it terminates into a
flat sphaleron or bisphaleron or into a Bartnik-McKinnon solution. These
bifurcation patterns are studied in some details.

</DOC>
<DOC>
<DOCNO> 151515 </DOCNO>
An Operator Valued Extension of the Super KdV Equations


  An extension of the Super KdV integrable system in terms of operator valued
functions is obtained. Following the ideas of Gardner, a general algebraic
approach for finding the infinitely many conserved quantities of integrable
systems is presented. The approach is applied to the above described system and
infinitely many conserved quantities are constructed. In a particular case they
reduce to the corresponding conserved quantities of Super KdV.

</DOC>
<DOC>
<DOCNO> 12717 </DOCNO>
Collective excitations of a two-dimensional interacting Bose gas in


  We present a method of finding approximate analytical solutions for the
spectra and eigenvectors of collective modes in a two-dimensional system of
interacting bosons subjected to a linear external potential or the potential of
a special form $u(x,y)=\mu -u \cosh^2 x/l$, where $\mu$ is the chemical
potential. The eigenvalue problem is solved analytically for an artificial
model allowing the unbounded density of the particles. The spectra of
collective modes are calculated numerically for the stripe, the rare density
valley and the edge geometry and compared with the analytical results. It is
shown that the energies of the modes localized at the rare density region and
at the edge are well approximated by the analytical expressions. We discuss
Bose-Einstein condensation (BEC) in the systems under investigations at $T\ne
0$ and find that in case of a finite number of the particles the regime of BEC
can be realized, whereas the condensate disappears in the thermodynamic limit.

</DOC>
<DOC>
<DOCNO> 119127 </DOCNO>
A supermassive boson star at the galactic center?


  We explore whether supermassive non-baryonic stars (in particular boson,
mini-boson and non-topological soliton stars) might be at the center of some
galaxies, with special attention to the Milky Way. We analyze, from a dynamical
point of view, what current observational data show, concluding that they are
compatible with a single supermassive object without requiring it to be a black
hole. Particularly, we show that scalar stars fit very well into these
dynamical requirements. The parameters of different models of scalar stars
necessary to reproduce the inferred central mass are derived, and the possible
existence of boson particles with the adequate range of masses is commented.
Accretion to boson stars is also analyzed, and a comparison with another
non-baryonic candidate, a massive neutrino ball, which is also claimed as an
alternative to the central black hole, is given. Both models are capable to
explain the nature of the object in Sgr A$^*$ without invoking the presence of
a singularity. One difficult issue is why the accreted materials will not
finally produce, in a sufficiently long time, a black hole. We provide an
answer based on stellar disruption in the case of boson stars, and comment
several suggestions for its possible solution in neutrino ball scenarios.
Finally, we discuss the prospects for the observational detection of these
supermassive scalar objects, using the new generation of X-ray and radio
interferometry satellites.

</DOC>
<DOC>
<DOCNO> 101121 </DOCNO>
Output Feedback Control for Stabilizable and Incompletely Observable


  This paper introduces a new approach for output feedback stabilization of
SISO systems which, unlike most of the techniques found in the literature, does
not use high-gain observers and control input saturation to achieve separation
between the state feedback and observer designs. Rather, we show that by using
nonlinear observers, together with a projection algorithm, the same kind of
separation principle is achieved for a larger class of systems, namely
stabilizable and incompletely observable plants. Furthermore, this new approach
avoids using knowledge of the inverse of the observability mapping, which is
needed by most techniques in the literature when controlling general
stabilizable systems.

</DOC>
<DOC>
<DOCNO> 68401 </DOCNO>
Polarized Moller Scattering Asymmetries


  The utility of polarized electron beams for precision electroweak studies is
described. Parity violating Moller scattering asymmetries in e-e- --> e-e- are
discussed. Effects of electroweak radiative corrections and the running
sin^2(theta_W(Q^2)) are reviewed. The sensitivity of E158 (a fixed target e-e-
experiment at SLAC) and future e-e- collider studies to ``new physics'' is
briefly outlined.

</DOC>
<DOC>
<DOCNO> 71665 </DOCNO>
Two-loop QCD corrections to massless identical quark scattering


  We present the two-loop virtual QCD corrections to the scattering of massless
identical quarks, q qbar to q qbar, in conventional dimensional regularisation
and using the MSbar scheme. The structure of the infrared divergences agrees
with that predicted by Catani while expressions for the finite remainder are
given for the q qbar to qbar q and the q q to q q (qbar qbar to qbar qbar)
scattering processes in terms of polylogarithms. The results presented here
form a vital part of the next-to-next-to-leading order contribution to
inclusive jet production in hadron colliders and will play a crucial role in
improving the theoretical prediction for jet cross sections in hadron-hadron
collisions.

</DOC>
<DOC>
<DOCNO> 174611 </DOCNO>
Identical transitions in the strongly deformed Sr-99 and Sr-100


  The decay of the very neutron-rich nucleus Rb-100 has been studied by
gamma-spectroscopy of on-line mass-separated samples. Schemes for beta-decay to
Sr-100 and beta-n-decay to Sr-99 are presented. New sets of transitions in
Sr-99 and Sr-100 with identical energies are observed. All identical bands so
far observed in neutron-rich Sr isotopes obey a simple energy rule valid for
even-even, odd-even and odd-odd bands.

</DOC>
<DOC>
<DOCNO> 178816 </DOCNO>
Relativistic Hartree-Bogoliubov description of sizes and shapes of A=20


  Ground-state properties of A = 20 nuclei ($^{20}$N, $^{20}$O, $^{20}$F,
$^{20}$Ne, $^{20}$Na, $^{20}$Mg) are described in the framework of Relativistic
Hartree-Bogoliubov (RHB) theory. The model uses the NL3 effective interaction
in the mean-field Lagrangian, and describes pairing correlations by the pairing
part of the finite range Gogny interaction D1S. Binding energies, quadrupole
deformations, nuclear matter radii, and differences in radii of proton and
neutron distributions are compared with recent experimental data.

</DOC>
<DOC>
<DOCNO> 151903 </DOCNO>
Gauge strata and particle generations


  Phenomenological evidence suggests the existence of non-trivial background
fields in the QCD vacuum. On the other hand SU(3) gauge theory possessses three
different classes of both non-generic and non-trivial strata that may be used
as classical backgrounds. It is suggested that this three-fold multiplicity of
non-trivial vacua may be related to the existence of particle generations,
which would then find an explanation in the framework of the standard model.

</DOC>
<DOC>
<DOCNO> 84124 </DOCNO>
Gravitational waves from quasi-spherical black holes


  A quasi-spherical approximation scheme, intended to apply to coalescing black
holes, allows the waveforms of gravitational radiation to be computed by
integrating ordinary differential equations.

</DOC>
<DOC>
<DOCNO> 71810 </DOCNO>
Is It Possible to Study the Wave Function of 2S Vector Mesons at HERA ?


  We present a short review of anomalous properties in diffractive photo- and
electroproduction of radially excited V'(2S) vector mesons. Using the color
dipole gBFKL phenomenology we analyze anomalous Q^{2} and energy dependence of
the production cross section, V'(2S)/V(1S) production ratio, the diffraction
slope and anomalous t behaviour of the differential cross section d\sigma/dt.
The origin of these anomalies is based on the interplay of the nodal structure
of V'(2S) radial wave function with the energy and dipole size dependence of
the dipole cross section and the diffraction slope. We analyze how a different
pattern of anomalous behaviour of V'(2S) production leads to a different
position of the node in the wave function and discuss how that node position
can be extracted from the data at HERA.

</DOC>
<DOC>
<DOCNO> 85423 </DOCNO>
Searching for continuous gravitational wave signals: the hierarchical


  It is well known that matched filtering techniques cannot be applied for
searching extensive parameter space volumes for continuous gravitational wave
signals. This is the reason why alternative strategies are being pursued.
Hierarchical strategies are best at investigating a large parameter space when
there exist computational power constraints. Algorithms of this kind are being
implemented by all the groups that are developing software for analyzing the
data of the gravitational wave detectors that will come online in the next
years. In this talk we will report about the hierarchical Hough transform
method that the GEO 600 data analysis team at the Albert Einstein Institute is
developing. The three step hierarchical algorithm has been described elsewhere.
In this talk we will focus on some of the implementational aspects we are
currently concerned with.

</DOC>
<DOC>
<DOCNO> 12097 </DOCNO>
Signature of Superfluid Density in the Single-Particle Excitation


  We report that the doping and temperature dependence of photoemission spectra
near the Brillouin zone boundary of Bi2Sr2CaCu2O8+delta exhibit unexpected
sensitivity to the superfluid density. In the superconducting state, the
photoemission peak intensity as a function of doping scales with the superfluid
density and the condensation energy. As a function of temperature, the peak
intensity shows an abrupt behavior near the superconducting phase transition
temperature where phase coherence sets in, rather than near the temperature
where the gap opens. This anomalous manifestation of collective effects in
single-particle spectroscopy raises important questions concerning the
mechanism of high-temperature superconductivity.

</DOC>
<DOC>
<DOCNO> 152151 </DOCNO>
Macroconstraints from Microsymmetries


  The dynamics governing the evolution of a many body system is constrained by
a nonabelian local symmetry. We obtain explicit forms of the global macroscopic
condition assuring that at the microscopic level the evolution respects the
overall symmetry constraint.

</DOC>
<DOC>
<DOCNO> 68158 </DOCNO>
SIMP (Strongly Interacting Massive Particle) Search


  We consider laboratory experiments that can detect stable, neutral strongly
interacting massive particles (SIMPs). We explore the SIMP annihilation cross
section from its minimum value (restricted by cosmological bounds) to the barn
range, and vary the mass values from a GeV to a TeV.
 We also consider the prospects and problems of detecting such particles at the
Tevatron.

</DOC>
<DOC>
<DOCNO> 69106 </DOCNO>
The Robustness of Inflation to Changes in Super-Planck-Scale Physics


  We calculate the spectrum of density fluctuations in models of inflation
based on a weakly self-coupled scalar matter field minimally coupled to
gravity, and specifically investigate the dependence of the predictions on
modifications of the physics on length scales smaller than the Planck length.
These modifications are encoded in terms of modified dispersion relations.
Whereas for some classes of dispersion relations the predictions are unchanged
compared to the usual ones which are based on a linear dispersion relation, for
other classes important differences are obtained, involving tilted spectra,
spectra with exponential factors and with oscillations. We conclude that the
predictions of inflationary cosmology in these models are not robust against
changes in the super-Planck-scale physics.

</DOC>
<DOC>
<DOCNO> 69016 </DOCNO>
Light Quark Masses to All Orders of Chiral Expansion


  We study light (current) quark masses in framework of chiral constitutent
quark model. In our calculation the current quark masses are defined uniquely,
and all order effects of the light quark masses are considered. The results at
energy scale $\mu=m_\rho$ are $m_s=(160\pm 15)$MeV, $m_s/m_d=20.2\pm 3.0$,
$m_u/m_d=0.5\pm 0.09$.

</DOC>
<DOC>
<DOCNO> 10477 </DOCNO>
Dynamical dimer-dimer correlation functions from exact diagonalization


  A regularization method is presented to deduce dynamic correlation functions
from exact diagonalization calculations. It is applied to dimer-dimer
correlation functions in quantum spin chains relevant for the description of
spin-Peierls systems. Exact results for the XY model are presented. The
analysis draws into doubt that the dimer-dimer correlation functions show the
same scale invariance as spin-spin correlation functions. The results are
applied to describe the quasi-elastic scattering in CuGeO$_3$.

</DOC>
<DOC>
<DOCNO> 7835 </DOCNO>
Anderson-Mott Transition in a Magnetic Field: Corrections to Scaling


  It is shown that the Anderson-Mott metal-insulator transition of
paramagnetic, interacting disordered electrons in an external magnetic field is
in the same universality class as the transition from a ferromagnetic metal to
a ferromagnetic insulator discussed recently. As a consequence, large
corrections to scaling exist in the magnetic-field universality class, which
have been neglected in previous theoretical descriptions. The nature and
consequences of these corrections to scaling are discussed.

</DOC>
<DOC>
<DOCNO> 39992 </DOCNO>
Linac*LHC Based ep, Gamma-p, eA, Gamma-A and FEL Gamma-A Colliders:


  Main parameters and physics goals of different colliders, which can be
realized if a special 1 TeV energy linear electron accelerator or corresponding
linear collider is constructed tangential to LHC, are discussed. It is shown
that L_(ep)=10^(32)cm^(-2)s^(-1) at sqrt(s_(ep))=5.29 TeV can be achieved
within moderate upgrade of LHC parameters. Then, Gamma-p collider with he same
luminosity and sqrt(s)=4.82 TeV can be realized using Compton backscattering of
laser beam off the electron beam. Concerning the nucleus beam,
L*A=10^(31)cm^(-2)s^(-1) can be achieved at least for light and medium nuclei
for both eA and Gamma-A options. Finally, colliding of FEL beam from an
electron linac and nucleus beam from LHC will give a new opportunity to
investigate nuclear spektroscopy and photo-nuclei reactions.

</DOC>
<DOC>
<DOCNO> 151776 </DOCNO>
Cosmological predictions from the Misner brane


  Within the spirit of five-dimensional gravity in the Randall-Sundrum
scenario, in this paper we consider cosmological and gravitational implications
induced by forcing the spacetime metric to satisfy a Misner-like symmetry. We
first show that in the resulting Misner-brane framework the Friedmann metric
for a radiation dominated flat universe and the Schwarzschild or anti-de Sitter
black holes metrics are exact solutions on the branes, but the model cannot
accommodate any inflationary solution. The horizon and flatness problems can
however be solved in Misner-brane cosmology by causal and noncausal
communications through the extra dimension between distant regions which are
outside the horizon. Based on a semiclassical approximation to the
path-integral approach, we have calculated the quantum state of the
Misner-brane universe and the quantum perturbations induced on its metric by
brane propagation along the fifth direction. We have then considered testable
predictions from our model. These include a scale-invariant spectrum of density
perturbations whose amplitude can be naturally accommodated to the required
value 10$^{-5}-10^{-6}$, and a power spectrum of CMB anisotropies whose
acoustic peaks are at the same sky angles as those predicted by inflationary
models, but having much smaller secondary-peak intensities. These predictions
seem to be compatible with COBE and recent Boomerang and Maxima measurements

</DOC>
<DOC>
<DOCNO> 170380 </DOCNO>
The asymptotic entanglement cost of preparing a quantum state


  We give a detailed proof of the conjecture that the asymptotic entanglement
cost of preparing a bipartite state \rho is equal to the regularized
entanglement of formation of \rho.

</DOC>
<DOC>
<DOCNO> 69069 </DOCNO>
Higgs Model without Elementary Scalars


  A model of interaction of massless vector and spinor fields is considered.
With the use of Bogolyubov quasi-average method we study a possibility of a
dynamical breaking of the initial symmetry. Assuming the existence of effective
cut-off $\Lambda$, we show, that there exists a solution, which breaks gauge
symmetry of the theory. Instead of Higgs scalars fermion-antifermion tachion
bound states are present here. As a result we have a theory with a massive
vector field, a massive spinor and a composite scalar.

</DOC>
<DOC>
<DOCNO> 151575 </DOCNO>
Heat Kernel Expansions for Distributional Backgrounds


  Heat kernel expansion coefficients are calculated for vacuum fluctuations
with distributional background potentials and field strengths. Terms up to and
including t^5/2 are presented.

</DOC>
<DOC>
<DOCNO> 71464 </DOCNO>
Hyperon Nonleptonic Weak Decays Revisited


  We first review the current algebra - PCAC approach to nonleptonic octet
baryon 14 weak decay B (\to) (B^{\prime})(\pi) amplitudes. The needed four
parameters are independently determined by (\Omega \to \Xi \pi),(\Lambda K) and
(\Xi ^{-}\to \Sigma ^{-}\gamma) weak decays in dispersion theory tree order. We
also summarize the recent chiral perturbation theory (ChPT) version of the
eight independent B (\to) (B^{\prime}\pi) weak (\Delta I) = 1/2 amplitudes
containing considerably more than eight low-energy weak constants in one-loop
order.

</DOC>
<DOC>
<DOCNO> 68232 </DOCNO>
Energy loss in perturbative QCD


  We review the properties of energetic parton propagation in hot or cold QCD
matter, as obtained in recent works. Advances in understanding the energy loss
- collisional and radiative - are summarized, with emphasis on the latter: it
features very interesting properties which may help to detect the quark-gluon
plasma produced in heavy ion collisions. We describe two different theoretical
approaches, which lead to the same radiated gluon energy spectrum. The case of
a longitudinally expanding QCD plasma is investigated. The energy lost by a jet
with given opening angle is calculated in view of making predictions for the
suppression (quenching) of hard jet production. Phenomenological implications
for the difference between hot and cold matter are discussed. Numerical
estimates of the loss suggest that it may be significantly enhanced in hot
compared to cold matter.

</DOC>
<DOC>
<DOCNO> 84839 </DOCNO>
Fermion Quantum Numbers and Families Replication from an Extension of


  The fermionic sector of the Standard Model of Elementary Particles emerges as
the low energy limit of a single fermionic field freely propagating in a higher
dimensional background. The local geometrical framework is obtained by
enforcing at a space-time level the whole gauge group SO(1,3) x U(1) x SU(2) x
SU(3) associated to fundamental interactions; equivalently, by assuming that
internal gauge transformations are indeed local space-time transformations. The
geometry naturally embodies freedoms corresponding to gravitational and
non-gravitational gauge fields. As a consequence of the fact that the
structural group is in part unitary, the motion of test particles gets
automatically squeezed on an effective 1+3 space-time. Dimensional reduction
takes place without compactification. In close analogy to the special
relativistic mass-energy relation, the theory associates to every elementary
particle an intrinsic energy presumably of the order of the Planck scale. The
theory predicts the existence of a right-handed component of the neutrino and
indicates the possibility of an extra U(1) gauge interaction.

</DOC>
<DOC>
<DOCNO> 69975 </DOCNO>
Testing Standard and Degenerate Big Bang Nucleosynthesis with BOOMERanG


  We test different Big Bang Nucleosynthesis scenarios using the recent results
on the Cosmic Microwave Background Anisotropies provided by the BOOMERanG and
MAXIMA-1 experiments versus the observed abundances of 4He, D and 7Li. The
likelihood analysis, based on Bayesian approach, shows that, in the case of
high deuterium abundance, Y_D=(2.0\pm0.5) 10^{-4}, both standard and degenerate
BBN are inconsistent with the CMBR measurement at more than 3 \sigma. Assuming
low deuterium abundance, Y_D=(3.4\pm0.3) 10^{-5}, the standard BBN model is
still inconsistent with present observations at 2 \sigma level, while the
degenerate BBN results to be compatible. Unless systematics effects will be
found in nuclide abundances and/or in CMBR data analysis this result may be a
signal in favour of new physics like a large chemical potential of the relic
neutrino-antineutrino background.

</DOC>
<DOC>
<DOCNO> 70998 </DOCNO>
Calculation of next-to-leading QCD corrections to b -> s gluon


  A detailed standard model (SM) calculation of the O(alpha_s) virtual
corrections to the decay width for b -> s g is presented (g denotes a gluon).
Also the complete expressions for the corresponding bremsstrahlung corrections
are given. Taking into account the existing next-to-leading logarithmic (NLL)
result for the Wilson coefficient C_8^eff, a complete NLL result for the
branching ratio BR(b->sg) is derived. Numerically, we obtain BR(b->sg)=(5.0 +/-
1.0) * 10^(-3), which is more than a factor of two larger than the leading
logarithmic result. The impact of these corrections on the inclusive charmless
hadronic branching ratio of B-mesons, which can be used to extract
|V_(ub)/V_(cb)|, is shown to be of similar importance as NLL corrections to
b-quark decay modes with three quarks in the final state. Finally, the impact
of the NLL corrections to b->sg on the charmless hadronic branching ratio is
investigated in scenarios, where the Wilson coefficient C_8 is enhanced by new
physics.

</DOC>
<DOC>
<DOCNO> 117589 </DOCNO>
Implementing Feedback in Simulations of Galaxy Formation: A Survey of


  We present a detailed investigation of different approaches to modeling
feedback in simulations of galaxy formation. Gas-dynamic forces are evaluated
using Smoothed Particle Hydrodynamics (SPH) while star formation and supernova
feedback are included using a three parameter model which determines the star
formation rate normalization, feedback energy and lifetime of feedback regions.
The star formation rate is calculated using a Lagrangian Schmidt Law for all
gas particles which satisfy temperature, density and convergent flow criteria.
Feedback is incorporated as thermal heating of the ISM. We compare the effects
of distributing this energy over the smoothing scale or depositing it on a
single particle. Radiative losses are prevented from heated particles by
adjusting the density used in radiative cooling. We test the models on the
formation of galaxies from cosmological initial conditions and also on isolated
Milky Way and dwarf galaxies. Extremely violent feedback is necessary to
produce a gas disk with angular momentum remotely close to that of observed
disk galaxies. This is a result of the extreme central concentration of the
dark halos in the sCDM model, and the pervasiveness of the core-halo angular
momentum transport mechanism. We emphasize that the disks formed in
hierarchical simulations are partially a numerical artifact produced by the
minimum mass scale of the simulation acting as a highly efficient `support'
mechanism. Disk formation is strongly affected by the treatment of dense
regions in SPH, which along with the difficulty of representing the
hierarchical formation process, means that realistic simulations of galaxy
formation require far higher resolution than currently used.

</DOC>
<DOC>
<DOCNO> 152462 </DOCNO>
Space-time discretization: the way to the fundamental element without a


  The concept of the random discretization of the space-time is suggested. It
is the way to consistent compatible synthesis of quantum and relativistic
principles and principle of geometrization. The basic idea of this concept is
physical reality of the finite sizes fundamental element of the quantized
space-time. The flat space-time with random discretization is described as the
probability measure space with the set of all possible discretizations of the
flat continual space-time as the set of points. The probability measure can
depend on the geometric parameters of discretizations (a number of regions of a
discretization, their volumes, areas etc.). In this concept the fundamental
length can be defined as the average value of the linear size of a fundamental
element. In this concept the "particle" quantum and the space-time quantum are
identical.

</DOC>
<DOC>
<DOCNO> 85481 </DOCNO>
Radial oscillations of relativistic stars


  We present a new survey of the radial oscillation modes of neutron stars.
This study complements and corrects earlier studies of radial oscillations. We
present an extensive list of frequencies for the most common equations of state
and some more recent ones. In order to check the accuracy, we use two different
numerical schemes which yield the same results. The stimulation for this work
comes from the need of the groups that evolve the full nonlinear Einstein
equation to have reliable results from perturbation theory for comparison.

</DOC>
<DOC>
<DOCNO> 10708 </DOCNO>
Importance of Correlation Effects on Magnetic Anisotropy in Fe and Ni


  We calculate magnetic anisotropy energy of Fe and Ni by taking into account
the effects of strong electronic correlations, spin-orbit coupling, and
non-collinearity of intra-atomic magnetization. The LDA+U method is used and
its equivalence to dynamical mean-field theory in the static limit is
emphasized. Both experimental magnitude of MAE and direction of magnetization
are predicted correctly near U=4 eV for Ni and U=3.5 eV for Fe. Correlations
modify one-electron spectra which are now in better agreement with experiments.

</DOC>
<DOC>
<DOCNO> 13257 </DOCNO>
Effect of Grain Geometry on Angle of Repose and Dynamics


  With simulation and experiment we examine the effect of grain anisotropy on
the angle of repose in a two-dimensional geometry. We find that the structure
of the granular packing can be directly controlled by changing the aspect ratio
of the grains, and that the specific type of order strongly affects the angle
of repose and the resulting dynamics. The angle of repose is largest for dimer
grains, and is smaller for both monomer and trimer grains. The motion of a
collapsing grain heap consists of large scale collective shear when monomer
grains are considered, but occurs via tumbling of grains on the surface for
dimers, and via disorderly bulk tumbling for trimer grains.

</DOC>
<DOC>
<DOCNO> 121593 </DOCNO>
Inflation and the dwarf galaxy problem


  Cosmological N-body simulations with scale-invariant initial perturbations
show too many virialized objects of dwarf-galaxy masses in a typical galactic
halo in contradiction to observation and stability of galactic discs. We
present a model of double hybrid inflation which predicts density fluctuations
with a small-scale cutoff to account for the absence of these objects in
observations.

</DOC>
<DOC>
<DOCNO> 123147 </DOCNO>
Why did Supernova 1054 shine at late times?


  The Crab nebula is the remnant of supernova 1054 (SN 1054). The progenitor of
this supernova has, based on nucleosynthesis arguments, been modeled as an 8-10
solar mass star. Here we point out that the observations of the late light
curve of SN 1054, from the historical records, are not compatible with the
standard scenario, in which the late time emission is powered by the
radioactive decay of small amounts of Ni-56. Based on model calculations we
quantify this discrepancy. The rather large mass of Ni-56 needed to power the
late time emission, 0.06[-0.03,+0.02] solar masses, seems inconsistent with
abundances in the Crab nebula. The late light curve may well have been powered
by the pulsar, which would make SN 1054 unique in this respect. Alternatively,
the late light curve could have been powered by circumstellar interaction, in
accordance with scenarios in which 8-10 solar mass stars are progenitors to
`dense wind' supernovae.

</DOC>
<DOC>
<DOCNO> 9086 </DOCNO>
Phonon Signature of Charge Inhomogeneity in High Temperature


  Temperature and composition dependences of high-energy longitudinal optical
(LO) phonons in YBa2Cu3O{6+x}, studied by inelastic neutron scattering
measurements, provide clear evidence for temperature dependent spatial
inhomogeneity of doped charges. The measurements indicate that charge doping
increases the volume fraction of the charged regions, while the local charge
density remains unchanged. For the optimally doped sample the charge
distribution changes sharply near the superconducting transition temperature,
with stronger charge inhomogeneity below Tc. The remarkable magnitude of the
phonon response to charge suggests strong involvement of phonons in charge
dynamics.

</DOC>
<DOC>
<DOCNO> 85324 </DOCNO>
Positive vacuum energy and the N-bound


  We argue that the total observable entropy is bounded by the inverse of the
cosmological constant. This holds for all space-times with a positive
cosmological constant, including cosmologies dominated by ordinary matter, and
recollapsing universes. The argument involves intermediate steps which may be
of interest in their own right. We note that entropy cannot be observed unless
it lies both in the past and in the future of the observer's history. This
truncates space-time to a diamond-shaped subset well-suited to the application
of the covariant entropy bound. We further require, and derive, a novel
Bekenstein-like bound on matter entropy in asymptotically de Sitter spaces. Our
main result lends support to the proposal that universes with positive
cosmological constant are described by a fundamental theory with only a finite
number of degrees of freedom.

</DOC>
<DOC>
<DOCNO> 152522 </DOCNO>
Topological symmetry breaking and the confinement of anyons


  We study topological symmetry breaking via the behaviour of Wilson and 't
Hooft loop operators for the 2+1 dimenesional Abelian-Higgs model with
Chern-Simons term. The topological linking of instantons, which are closed
vortex loop configurations, give rise to a long-range, logarithmic, confining
potential between electric charges and magnetic flux tubes even though all
perturbative forces are short range. Gauss' law forces the concomitance of
charge and magnetic flux, hence the confinement is actually of anyons.

</DOC>
<DOC>
<DOCNO> 119164 </DOCNO>
Accretion Disks Phase Transitions: 2-D or not 2-D?


  We argue that the proper way to treat thin-thick accretion-disk transitions
should take into account the 2-D nature of the problem. We illustrate the
physical inconsistency of the 1-D vertically integrated approach by discussing
a particular example of the convective transport of energy.

</DOC>
<DOC>
<DOCNO> 169748 </DOCNO>
Non-Kolmogorov probability models and modified Bell's inequality


  We analyse the proof of Bell's inequality and demonstrate that this
inequality is related to one particular model of probability theory, namely
Kolmogorov measure-theoretical axiomatics, 1933. We found a (numerical)
statistical correction to Bell's inequality. Such an additional term in the
right hand side of Bell's inequality can be considered as a probability
invariant of a quantum state. This is a measure of nonreproducibility of hidden
variables in different runs of experiments. Experiments to verify Bell's
inequality can be considered as just experiments to estimate this constant. It
seems that Bell's inequality could not be used as a crucial reason to deny
local realism. We consider deterministic as well as stochastic hidden variables
models.

</DOC>
<DOC>
<DOCNO> 9368 </DOCNO>
Moment of Inertia and Quadrupole Response Function of a Trapped


  We derive an explicit relationship between the moment of inertia and the
quadrupole response function of an interacting gas confined in a harmonic trap.
The relationship holds for both Bose and Fermi systems and is well suited to
reveal the effects of irrotationality of the superfluid motion. Recent
experimental results on the scissors mode are used to extract the value of the
moment of inertia of a trapped Bose gas and to point out the deviations from
the rigid value due to superfluidity.

</DOC>
<DOC>
<DOCNO> 11659 </DOCNO>
Simulations of the kinetic friction due to adsorbed surface layers


  Simulations of the kinetic friction due to a layer of adsorbed molecules
between two crystalline surfaces are presented. The adsorbed layer naturally
produces friction that is consistent with Amontons' laws and insensitive to
parameters that are not controlled in experiments. The kinetic friction rises
logarithmically with velocity as in many experimental systems. Variations with
potential parameters and temperature follow variations in the static friction.
This correlation is understood through analogy with the Tomlinson model and the
trends are explained with a hard-sphere picture.

</DOC>
<DOC>
<DOCNO> 83378 </DOCNO>
Computing Crossing Numbers in Quadratic Time


  We show that for every fixed non-negative integer k there is a quadratic time
algorithm that decides whether a given graph has crossing number at most k and,
if this is the case, computes a drawing of the graph in the plane with at most
k crossings.

</DOC>
<DOC>
<DOCNO> 116330 </DOCNO>
The oscillations in the lossy medium


  The object of this laboratory work: to explore dependence mass point
oscillatory motion parameters in the following cases:
  - without resistance (free oscillations);
  - the resistance force is proportional to the velocity vector;
  - the resistance force is proportional to the velocity squared.
  Used equipment: the work have doing on a personal computer. The oscillatory
motion simulation is carried out by the numerical solution of system of
differential equations. This equations describe a motion of a particle under an
elastic force action and exterior forces (resistance force) with initial values
and parameters being entered during the dialogue with the computer.

</DOC>
<DOC>
<DOCNO> 102734 </DOCNO>
The Growth of Grigorchuk's Group


  In 1980 Rostislav Grigorchuk constructed a group $G$ of intermediate growth,
and later obtained the following estimates on its growth function:
$$e^{\sqrt{n}}\precsim\gamma(n)\precsim e^{n^\beta},$$ where
$\beta=\log_{32}(31)\approx0.991$. Using elementary methods we bring the upper
bound down to $\log(2)/\log(2/\eta)\approx0.767$, where $\eta\approx0.811$ is
the real root of the polynomial $X^3+X^2+X-2$.

</DOC>
<DOC>
<DOCNO> 8850 </DOCNO>
Multi-excitons in self-assembled InAs/GaAs quantum dots: A


  We use a many-body, atomistic empirical pseudopotential approach to predict
the multi-exciton emission spectrum of a lens shaped InAs/GaAs self-assembled
quantum dot. We discuss the effects of (i) The direct Coulomb energies,
including the differences of electron and hole wavefunctions, (ii) the exchange
Coulomb energies and (iii) correlation energies given by a configuration
interaction calculation. Emission from the groundstate of the $N$ exciton
system to the $N-1$ exciton system involving $e_0\to h_0$ and $e_1\to h_1$
recombinations are discussed. A comparison with a simpler single-band,
effective mass approach is presented.

</DOC>
<DOC>
<DOCNO> 102876 </DOCNO>
Quaternionic holomorphic geometry: Pluecker formula, Dirac eigenvalue


  The paper develops the fundamentals of quaternionic holomorphic curve theory.
The holomorphic functions in this theory are conformal maps from a Riemann
surface into the 4-sphere, i.e., the quaternionic projective line. Basic
results such as the Riemann-Roch Theorem for quaternionic holomorphic vector
bundles, the Kodaira embedding and the Pluecker relations for linear systems
are proven. Interpretations of these results in terms of the differential
geometry of surfaces in 3- and 4-space are hinted at throughout the paper.
Applications to estimates of the Willmore functional on constant mean curvature
tori, respectively energy estimates of harmonic 2-tori, and to Dirac eigenvalue
estimates on Riemannian spin bundles in dimension 2 are given.

</DOC>
<DOC>
<DOCNO> 68706 </DOCNO>
Monopole Chern-Simons Term: Charge-Monopole System as a Particle with


  The topological nature of Chern-Simons term describing the interaction of a
charge with magnetic monopole is manifested in two ways: it changes the plane
dynamical geometry of a free particle for the cone dynamical geometry without
distorting the free (geodesic) character of the motion, and in the limit of
zero charge's mass it describes a spin system. This observation allows us to
interpret the charge-monopole system alternatively as a free particle of fixed
spin with translational and spin degrees of freedom interacting via the
helicity constraint, or as a symmetric spinning top with dynamical moment of
inertia and "isospin" U(1) gauge symmetry, or as a system with higher
derivatives. The last interpretation is used to get the twistor formulation of
the system. We show that the reparametrization and scale invariant monopole
Chern-Simons term supplied with the kinetic term of the same invariance gives
rise to the alternative description for the spin, which is related to the
charge-monopole system in a spherical geometry. The relationship between the
charge-monopole system and (2+1)-dimensional anyon is discussed in the light of
the obtained results.

</DOC>
<DOC>
<DOCNO> 99432 </DOCNO>
Two dimensional Einstein-Weyl structures


  All local solutions of the two dimensional Einstein-Weyl equations are found,
and related to the compact examples which I obtained in "Moebius structures and
two dimensional Einstein-Weyl geometry" J. reine angew. Math. 504 (1998).

</DOC>
<DOC>
<DOCNO> 12441 </DOCNO>
Charge Ordering and Polaron Formation in the Magnetoresistive Oxide


  Neutron scattering has been used to study the nature of the ferromagnetic
transition in a single crystal of the perovskite La0.7Ca0.3MnO3. Diffuse
scattering from lattice polarons develops as the Curie temperature is
approached from below, along with short range polaron correlations that are
consistent with stripe formation. Both the scattering due to the polaron
correlations and the anomalous quasielastic component in the magnetic
fluctuation spectrum maximize very close to T_C, in a manner remarkably similar
to the resistivity, indicating that they have a common origin.

</DOC>
<DOC>
<DOCNO> 71240 </DOCNO>
Chiral Expansion Theory at Vector Meson Scale


  We study physics on $\rho(770)$ and $\omega(782)$ in framework of chiral
constituent quark model. The effective action is derived by proper vertex
method, which can capture all order information of chiral expansion. The
$N_c^{-1}$ expansion is also studied systematically. It is shown that the
momentum expansion at vector meson energy scale converges slowly, and the loop
effects of pseudoscalar meson play an important role at this energy scale. We
provide a method to prove the unitarity of S-matrix in any low-energy effective
theory of QCD. Phenomenologically, we study decays for $\rho\to\pi\pi$,
$\rho\to e^+e^-$, $\omega\to\pi^+\pi^-$, $\rho^\pm\to\gamma\pi^\pm$ and
$\omega\to\gamma\pi^0$, $\rho^0-\omega$ mixing and their mass splitting, pion
form factor, $I=l=1$ phase shift and light quark masses at vector meson energy
scale. These results include all order contribution of vector meson momentum
expansion and is up to next to leading order of $N_c^{-1}$ expansion. All of
these theoretical predictions agree with data very well. The unitarity of
S-matrix yielded by this framework is examined. The Breit-Winger formula for
resonance propagator is derived.

</DOC>
<DOC>
<DOCNO> 101448 </DOCNO>
Projectivity of modules for infinitesimal unipotent group schemes


  In this paper, it is shown that the projectivity of a rational module for an
infinitesimal unipotent group scheme over an algebraically closed field of
positive characteristic can be detected on a family of closed subgroups.

</DOC>
<DOC>
<DOCNO> 116629 </DOCNO>
Long-range interaction of two metastable rare-gas atoms


  We present semiempirical calculations of long-range van der Waals
interactions for two interacting metastable rare-gas atoms Ne through Xe.
Dispersion coefficients $C_6$ are obtained for homonuclear molecular potentials
asymptotically connecting to the $ns(3/2)_{2} + ns(3/2)_{2}$ atomic states. The
estimated uncertainty of the calculated $C_6$ dispersion coefficients is 4%.

</DOC>
<DOC>
<DOCNO> 151239 </DOCNO>
Renormalization Group Study of Chern-Simons Field Coupled to Scalar


  We apply a soft version of the BPHZ subtraction scheme to the computation of
two-loop corrections from an Abelian Chern-Simons field coupled to (massive)
scalar matter with a $\lambda(\Phi^\dag\Phi)^2$ and $\nu(\Phi^\dag\Phi)^3$
self-interactions. The two-loop renormalization group functions are calculated.
We compare our results with those in the literature.

</DOC>
<DOC>
<DOCNO> 71535 </DOCNO>
Magnetic Collapse of a Neutron Gas: No Magnetar Formation


  A degenerate neutron gas in equilibrium with a background of electrons and
protons in a magnetic field exerts its pressure anisotropically, having a
smaller value perpendicular than along the magnetic field. For critical fields
the magnetic pressure may produce the vanishing of the equatorial pressure of
the neutron gas, and the outcome could be a transverse collapse of the star.
This fixes a limit to the fields to be observable in stable pulsars as a
function of their density. The final structure left over after the implosion
might be a mixed phase of nucleons and meson ($\pi^{\pm,0},\kappa^{\pm,0}$)
condensate (a strange star also likely) or a black string, but no magnetar at
all.

</DOC>
<DOC>
<DOCNO> 151566 </DOCNO>
Half-Branes, Singular Brane Intersections, and Kaluza-Klein reduction


  Two subtle aspects of brane intersections are investigated. The first
concerns the `half-branes' that arise in discussions of the Hanany-Witten
effect, often in the D0/D8 setting. The second involves the validity of
seemingly singular classical BPS brane intersections. A study of holomorphic
curves in the background of a Kaluza-Klein monopole and the associated
reduction to type IIA supergravity sheds light on both issues. Many seemingly
singular D2/D6 intersections are shown to lift to smooth configurations of
M2-branes in 11-dimensions, and a mechanism is found for certain $Z_2$
confinement effects in type II string theories that eliminates any need for
half-branes.

</DOC>
<DOC>
<DOCNO> 178917 </DOCNO>
Isospin effects on rotational flow in intermediate energy heavy ion


  Within the framework of an isospin-dependent quantum molecular dynamics
model, the rotational flow in reactions of $^{58}$Fe + $^{58}$Fe and $^{58}$%
Ni + $^{58}$Ni at 40 MeV/nucleon for different impact parameters is
investigated by analyzing the mid-rapidity azimuthal distribution. The
rotational observables are also calculated semiquantitatively. For the first
time, it is found that the more neutron-rich system ($^{58}$Fe + $^{58}$Fe)
exhibits stronger rotational collective flow. This isospin dependence of
rotational collective flow is more appreciable in semi-peripheral collisions
and it is shown to mainly result from the isospin dependence of nucleon-nucleon
cross section rather than the symmetry energy. Meanwhile, it is indicated that
the rotational flow depends strongly on the impact parameter.

</DOC>
<DOC>
<DOCNO> 12672 </DOCNO>
Quantum Size Effect transition in percolating nanocomposite films


  We report on unique electronic properties in Fe-SiO2 nanocomposite thin films
in the vicinity of the percolation threshold. The electronic transport is
dominated by quantum corrections to the metallic conduction of the Infinite
Cluster (IC). At low temperature, mesoscopic effects revealed on the
conductivity, Hall effect experiments and low frequency electrical noise
(random telegraph noise and 1/f noise) strongly support the existence of a
temperature-induced Quantum Size Effect (QSE) transition in the metallic
conduction path. Below a critical temperature related to the geometrical
constriction sizes of the IC, the electronic conductivity is mainly governed by
active tunnel conductance across barriers in the metallic network. The high 1/f
noise level and the random telegraph noise are consistently explained by random
potential modulation of the barriers transmittance due to local Coulomb
charges. Our results provide evidence that a lowering of the temperature is
somehow equivalent to a decrease of the metal fraction in the vicinity of the
percolation limit.

</DOC>
<DOC>
<DOCNO> 99488 </DOCNO>
Summation and transformation formulas for elliptic hypergeometric series


  Using matrix inversion and determinant evaluation techniques we prove several
summation and transformation formulas for terminating, balanced,
very-well-poised, elliptic hypergeometric series.

</DOC>
<DOC>
<DOCNO> 80665 </DOCNO>
Feynman Diagrams of Generalized Matrix Models and the Associated


  The problem of constructing a quantum theory of gravity has been tackled with
very different strategies, most of which relying on the interplay between ideas
from physics and from advanced mathematics. On the mathematical side, a central
role is played by combinatorial topology, often used to recover the space-time
manifold from the other structures involved. An extremely attractive
possibility is that of encoding all possible space-times as specific Feynman
diagrams of a suitable field theory. In this work we analyze how exactly one
can associate combinatorial 4-manifolds to the Feynman diagrams of certain
tensor theories.

</DOC>
<DOC>
<DOCNO> 13811 </DOCNO>
Stochastic resonance in a suspension of magnetic dipoles under shear


  We show that a magnetic dipole in a shear flow under the action of an
oscillating magnetic field displays stochastic resonance in the linear response
regime. To this end, we compute the classical quantifiers of stochastic
resonance, i.e. the signal to noise ratio, the escape time distribution, and
the mean first passage time. We also discuss limitations and role of the linear
response theory in its applications to the theory of stochastic resonance.

</DOC>
<DOC>
<DOCNO> 122711 </DOCNO>
Evidence of a Supermassive Black Hole in the Galaxy NGC 1023 from the


  We analyze the nuclear stellar dynamics of the SB0 galaxy NGC 1023, utilizing
observational data both from the Space Telescope Imaging Spectrograph aboard
the Hubble Space Telescope and from the ground. The stellar kinematics measured
from these long-slit spectra show rapid rotation (V = 70 km/s at a distance of
0.1 arcsec = 4.9 pc from the nucleus) and increasing velocity dispersion toward
the nucleus (where sigma = 295 +/- 30 km/s). We model the observed stellar
kinematics assuming an axisymmetric mass distribution with both two and three
integrals of motion. Both modeling techniques point to the presence of a
central dark compact mass (which presumably is a supermassive black hole) with
confidence > 99%. The isotropic two-integral models yield a best-fitting black
hole mass of (6.0 +/- 1.4) x 10^7 M_sun and mass-to-light ratio (M/L_V) of 5.38
+/- 0.08, and the goodness-of-fit (chi^2) is insensitive to reasonable values
for the galaxy's inclination. The three-integral models, which
non-parametrically fit the observed line-of-sight velocity distribution as a
function of position in the galaxy, suggest a black hole mass of (3.9 +/- 0.4)
x 10^7 M_sun and M/L_V of 5.56 +/- 0.02 (internal errors), and the edge-on
models are vastly superior fits over models at other inclinations. The internal
dynamics in NGC 1023 as suggested by our best-fit three-integral model shows
that the velocity distribution function at the nucleus is tangentially
anisotropic, suggesting the presence of a nuclear stellar disk. The nuclear
line of sight velocity distribution has enhanced wings at velocities >= 600
km/s from systemic, suggesting that perhaps we have detected a group of stars
very close to the central dark mass.

</DOC>
<DOC>
<DOCNO> 118735 </DOCNO>
Cross-correlating CMB polarization with local large scale structures


  We study heterogeneous quantities that efficiently cross-correlate the
lensing information encoded in CMB polarization and large-scale structures
recovered from weak lensing galaxy surveys. These quantities allow us to take
advantage of the special features of weak lensing effect on CMB B-polarization
and of the high (40%) cross-correlation between the two data sets. We show that
these objects are robust to filtering effects, have a low intrinsic cosmic
variance (around 8% for small 100 square degrees surveys) and can be used as an
original constraint on the vacuum energy density.

</DOC>
<DOC>
<DOCNO> 118683 </DOCNO>
HS 0822+3542 - a new nearby extremely metal-poor galaxy


  We present the results of spectrophotometry and BVR CCD photometry, as well
as integrated HI radio measurements of a new blue compact galaxy (BCG) HS
0822+3542 with extremely low oxygen abundance: 12+log(O/H) = 7.35, or 1/36 of
solar value. The galaxy is the third most metal-deficient BCG after I Zw 18 and
SBS 0335-052. Its very high mass fraction of gas (~95% of all visible mass) and
blue colours of underlying nebulosity are also similar to those of SBS
0335-052. This suggests that HS 0822+3542 is one of the nearest and dimmest
galaxies experiencing a recently-started first star formation (SF) episode. Its
properties imply that for such galaxies there is a linear scaling of the main
parameters, at least for the baryon mass range (0.3-20)x10^8 M_sun. The total
mass estimate indicates that the galaxy is dynamically dominated by a dark
matter (DM) halo, which itself is one of the least massive for galaxies.

</DOC>
<DOC>
<DOCNO> 116405 </DOCNO>
On the uniqueness of the surface sources of evoked potentials


  The uniqueness of a surface density of sources localized inside a spatial
region $R$ and producing a given electric potential distribution in its
boundary $B_0$ is revisited. The situation in which $R$ is filled with various
metallic subregions, each one having a definite constant value for the electric
conductivity is considered. It is argued that the knowledge of the potential in
all $B_0$ fully determines the surface density of sources over a wide class of
surfaces supporting them. The class can be defined as a union of an arbitrary
but finite number of open or closed surfaces. The only restriction upon them is
that no one of the closed surfaces contains inside it another (nesting) of the
closed or open surfaces.

</DOC>
<DOC>
<DOCNO> 83231 </DOCNO>
Conditional Plausibility Measures and Bayesian Networks


  A general notion of algebraic conditional plausibility measures is defined.
Probability measures, ranking functions, possibility measures, and (under the
appropriate definitions) sets of probability measures can all be viewed as
defining algebraic conditional plausibility measures. It is shown that the
technology of Bayesian networks can be applied to algebraic conditional
plausibility measures.

</DOC>
<DOC>
<DOCNO> 10179 </DOCNO>
Dynamic splitting of a Bose-Einstein Condensate


  We study the dynamic process of splitting a condensate by raising a potential
barrier in the center of a harmonic trap. We use a two-mode model to describe
the phase coherence between the two halves of the condensate. Furthermore, we
explicitly consider the spatial dependence of the mode funtions, which varies
depending on the potential barrier. This allows to get the tunneling coupling
between the two wells and the on-site energy as a function of the barrier
height. Moreover we can get some insight on the collective modes which are
excited by raising the barrier. We describe the internal and external degrees
of freedom by variational ansatz. We distinguish the possible regimes as a
function of the characteristic parameters of the problem and identify the
adiabaticity conditions.

</DOC>
<DOC>
<DOCNO> 83502 </DOCNO>
Slicing of Constraint Logic Programs


  Slicing is a program analysis technique originally developed for imperative
languages. It facilitates understanding of data flow and debugging.
  This paper discusses slicing of Constraint Logic Programs. Constraint Logic
Programming (CLP) is an emerging software technology with a growing number of
applications. Data flow in constraint programs is not explicit, and for this
reason the concepts of slice and the slicing techniques of imperative languages
are not directly applicable.
  This paper formulates declarative notions of slice suitable for CLP. They
provide a basis for defining slicing techniques (both dynamic and static) based
on variable sharing. The techniques are further extended by using groundness
information.
  A prototype dynamic slicer of CLP programs implementing the presented ideas
is briefly described together with the results of some slicing experiments.

</DOC>
<DOC>
<DOCNO> 116552 </DOCNO>
Nonlinear interference effects in emission, absorption, and generation


  Nonlinear effects in emission and absorption spectra of gaseous systems are
considered. It is shown that level splitting can be detected spectroscopically
even if it is below the Doppler width. Conditions for distinguishing
interference effects from those due to nonequilibrium velocity distribution are
determined. In the case of large Doppler broadening the correction for atomic
motion is equivalent to the substitution of an "effective immobile atom" for
the moving atom ensemble. The spectral manifestation of nonlinear effects is
analyzed in detail. The influence of nonlinear interference effects on the
generation characteristics in the presence of external field is investigated.

</DOC>
<DOC>
<DOCNO> 116945 </DOCNO>
RF Cavities For The Muon and Neutrino Factory Collaboration Study


  A multi-laboratory collaboration is studying the feasibility of building a
muon collider, the first phase of which maybe a neutrino factory. The phase
space occupied by the muons is very large and needs to be cooled several orders
of magnitude for either machine, 100,000 to 1 million for the collider and ten
to 100 for the factory. Ionization cooling is the base line method for muon
cooling. This scheme uses hydrogen absorbers and rf re-acceleration in a long
series of magnetic focusing channels to cool the muons. At Fermilab two rf
cavity types are under study to provide the required cooling rf
re-acceleration, a 805 MHz high gradient cavity for the collider and a 201 MHz
high gradient cavity for the neutrino factory. The 805 MHz cavity currently
under going cold testing is a non-periodic pi-mode cavity with the iris
openings shaped to follow the contour of the beam. The 201 MHz cavity uses
hollow thin metal tubes over the beam aperture to terminate the field in a
pill-box type mode to increase its shunt impedance. This is possible because
muons have little interactions with thin metal membranes. Details of these
cavities and cold measurement data will be presented.

</DOC>
<DOC>
<DOCNO> 39621 </DOCNO>
Problems and stoppers for gamma-gamma, gamma-mu, mu-p colliders using


  It is well known that at linear e^+e^-(e^-e^-) colliders using laser
backscattering one can obtain colliding gamma-gamma, gamma-electron beams with
energy and luminosity comparable to those in e^+e^- collisions. In this paper,
it is explained why this can not be done at high energy muon colliders. Due to
several physics reasons the gamma-gamma luminosity is suppressed here by a
factor of 10^{14} ! Another option -- gamma's from a linear collider and muons
from a muon collider -- is also discussed (and has no sense either). Of course,
one can study gamma^*-muon and gamma^*-gamma^* interactions at muon colliders
in collisions with virtual photons as it is done now at e^+e^- storage rings.
Muon-proton colliders are attractive only if the proton beam is cooled and has
the same parameters as the muon beam, in which case
 L_{\mu p} \sim L_{\mu\mu}.

</DOC>
<DOC>
<DOCNO> 101205 </DOCNO>
Exponential forms and path integrals for complex numbers in n dimensions


  Two distinct systems of commutative complex numbers in n dimensions are
described, of polar and planar types. Exponential forms of n-complex numbers
are given in each case, which depend on geometric variables. Azimuthal angles,
which are cyclic variables, appear in these forms at the exponent, and this
leads to the concept of residue for path integrals of n-complex functions. The
exponential function of an n-complex number is expanded in terms of functions
called in this paper cosexponential functions, which are generalizations to n
dimensions of the circular and hyperbolic sine and cosine functions. The
factorization of n-complex polynomials is discussed.

</DOC>
<DOC>
<DOCNO> 122435 </DOCNO>
The mass of a halo


  We discuss the different definitions of the mass of a halo in common use and
how one may convert between them. Using N-body simulations we show that mass
estimates based on spherical averages are much more tightly correlated with
each other than with masses based on the number of particles in a halo. The
mass functions pertaining to some different mass definitions are estimated and
compared to the `universal form' of Jenkins et al. (2000). Using a different
simulation pipeline and a different cosmological model we show that the mass
function is well fit by the Jenkins et al. (2000) fitting function,
strengthening the claim to universality made by those authors. We show that
care must be taken to match the definitions of mass when using large N-body
simulations to bootstrap scaling relations from smaller hydrodynamical runs to
avoid observationally significant bias in the predictions for abundances of
objects.

</DOC>
<DOC>
<DOCNO> 102521 </DOCNO>
Quillen model structures for relative homological algebra


  An important example of a model category is the category of unbounded chain
complexes of R-modules, which has as its homotopy category the derived category
of the ring R. This example shows that traditional homological algebra is
encompassed by Quillen's homotopical algebra. The goal of this paper is to show
that more general forms of homological algebra also fit into Quillen's
framework. Specifically, a projective class on a complete and cocomplete
abelian category A is exactly the information needed to do homological algebra
in A. The main result is that, under weak hypotheses, the category of chain
complexes of objects of A has a model category structure that reflects the
homological algebra of the projective class in the sense that it encodes the
Ext groups and more general derived functors. Examples include the "pure
derived category" of a ring R, and derived categories capturing relative
situations, including the projective class for Hochschild homology and
cohomology. We characterize the model structures that are cofibrantly
generated, and show that this fails for many interesting examples. Finally, we
explain how the category of simplicial objects in a possibly non-abelian
category can be equipped with a model category structure reflecting a given
projective class, and give examples that include equivariant homotopy theory
and bounded below derived categories.

</DOC>
<DOC>
<DOCNO> 102347 </DOCNO>
The eigenvectors of the right-justified Pascal triangle


  We find the eigenvalues and eigenvectors of the n by n matrix with (i,j)
entry \binom(i-1,n-j), establishing a conjecture of Peele and Stanica.
Curiously, the eigenvectors can be chosen to form a matrix which is its own
inverse.

</DOC>
<DOC>
<DOCNO> 13865 </DOCNO>
The Quantum Spherical p-Spin-Glass Model


  We study a quantum extension of the spherical $p$-spin-glass model using the
imaginary-time replica formalism. We solve the model numerically and we discuss
two analytical approximation schemes that capture most of the features of the
solution. The phase diagram and the physical properties of the system are
determined in two ways: by imposing the usual conditions of thermodynamic
equilibrium and by using the condition of marginal stability. In both cases,
the phase diagram consists of two qualitatively different regions. If the
transition temperature is higher than a critical value $T^{\star}$, quantum
effects are qualitatively irrelevant and the phase transition is {\it second}
order, as in the classical case. However, when quantum fluctuations depress the
transition temperature below $T^{\star}$, the transition becomes {\it first
order}. The susceptibility is discontinuous and shows hysteresis across the
first order line, a behavior reminiscent of that observed in the dipolar Ising
spin-glass LiHo$_x$Y$_{1-x}$F$_4$ in an external transverse magnetic field. We
discuss in detail the thermodynamics and the stationary dynamics of both
states. The spectrum of magnetic excitations of the equilibrium spin-glass
state is gaped, leading to an exponentially small specific heat at low
temperatures. That of the marginally stable state is gapless and its specific
heat varies linearly with temperature, as generally observed in glasses at low
temperature. We show that the properties of the marginally stable state are
closely related to those obtained in studies of the real-time dynamics of the
system weakly coupled to a quantum thermal bath. Finally, we discuss a possible
application of our results to the problem of polymers in random media.

</DOC>
<DOC>
<DOCNO> 123313 </DOCNO>
Advective Flow Paradigm And Microquasar GRS1915+105


  Advective accretion disks and winds are the most self-consistent solutions
today. We describe this paradigm briefly and show how it attempts to explain
some of the interesting observations of the galactic microquasar GRS1915+105.

</DOC>
<DOC>
<DOCNO> 150774 </DOCNO>
Fields on the Poincare group: arbitrary spin description and


  In this paper, starting from pure group-theoretical point of view, we develop
a regular approach to describing particles with different spins in the
framework of a theory of scalar fields on the Poincare group. Such fields can
be considered as generating functions for conventional spin-tensor fields. The
cases of 2, 3, and 4 dimensions are elaborated in detail. Discrete
transformations $C,P,T$ are defined for the scalar fields as automorphisms of
the Poincare group. Doing a classification of the scalar functions, we obtain
relativistic wave equations for particles with definite spin and mass. There
exist two different types of scalar functions (which describe the same mass and
spin), one related to a finite-dimensional nonunitary representation and
another one related to an infinite-dimensional unitary representation of the
Lorentz subgroup. This allows us to derive both usual finite-component wave
equations for spin-tensor fields and positive energy infinite-component wave
equations.

</DOC>
<DOC>
<DOCNO> 100815 </DOCNO>
Geometric Interpretations of Quandle Homology


  Geometric representations of cycles in quandle homology theory are given in
terms of colored knot diagrams. Abstract knot diagrams are generalized to
diagrams with exceptional points which, when colored, correspond to degenerate
cycles. Bounding chains are realized, and used to obtain equivalence moves for
homologous cycles. The methods are applied to prove that boundary homomorphisms
in a homology exact sequence vanish.

</DOC>
<DOC>
<DOCNO> 8206 </DOCNO>
Master Operators Govern Multifractality in Percolation


  Using renormalization group methods we study multifractality in percolation
at the instance of noisy random resistor networks. We introduce the concept of
master operators. The multifractal moments of the current distribution (which
are proportional to the noise cumulants $C_R^{(l)} (x, x^\prime)$ of the
resistance between two sites x and $x^\prime$ located on the same cluster) are
related to such master operators. The scaling behavior of the multifractal
moments is governed exclusively by the master operators, even though a myriad
of servant operators is involved in the renormalization procedure. We calculate
the family of multifractal exponents ${\psi_l}$ for the scaling behavior of the
noise cumulants, $C_R^{(l)} (x, x^\prime) \sim | x - x^\prime |^{\psi_l /\nu}$,
where $\nu$ is the correlation length exponent for percolation, to two-loop
order.

</DOC>
<DOC>
<DOCNO> 99762 </DOCNO>
On the isotriviality of families of projective manifolds over curves


  Let Y be a projective non-singular curve of genus g, X a projective manifold,
both defined over the field of complex numbers, and let f:X ---> Y be a
surjective morphism with general fibre F.
    If the Kodaira dimension of X is non-negative, and if Y is the projective
line we show that f has at least 3 singular fibres.
    In general, for non-isotrivial morphisms f, one expects that the number of
singular fibres is at least 3, if g=0, or at least 1, if g=1. Using the strong
additivity of the Kodaira dimension, this is verified, if either F is of
general type, or if F has a minimal model with a semi-ample canonical divisor.
The corresponding result has been obtained by Migliorini and Kovacs, for
families of surfaces of general type and for families of canonically polarized
manifolds, and by Oguiso-Viehweg for families of elliptic surfaces.
    As a byproduct we obtain explicit bounds for the degree of the direct image
of powers of the dualizing sheaf, generalizing those obtained by
Bedulev-Viehweg for families of surfaces of general type.

</DOC>
<DOC>
<DOCNO> 118682 </DOCNO>
Problems of the matter increase in our observed expansive and isotropic


  The increase in mass of our observed expansive and isotropic relativistic
Universe in the present relativistic cosmology is explained by the extensive
assumption of the matter objects emerging on the horizon (of the most remote
visibility). However, the physical analysis unambiguously shows that this
assumption contradicts the theory of relativity, quantum mechanics, classical
mechanics and observations.

</DOC>
<DOC>
<DOCNO> 70847 </DOCNO>
Effects of Longitudinal Photons


  The description of longitudinal photons is far from trivial, and their
phenomenological importance is largely unknown. While the cross section for
direct interactions is calculable, an even more important contribution could
come from resolved states. In the development of our model for the interactions
of (real and) virtual photons, we have modeled resolved longitudinal effects by
simple multiplicative factors on the resolved transverse-photon contributions.
Recently, a first set of parton distributions for longitudinal virtual photons
has been presented by Ch\'yla. We therefore compare their impact on some
representative distributions, relative to the simpler approaches.

</DOC>
<DOC>
<DOCNO> 179021 </DOCNO>
Quasi-SU(3) truncation scheme for odd-even sd-shell nuclei


  The quasi-SU(3) symmetry, as found in shell model calculations, refers to the
dominance of the single particle plus quadrupole-quadrupole terms in the
Hamiltonian used to describe well deformed nuclei, and to the subspace relevant
in its diagonalization. It provides a very efficient basis truncation scheme.
It is shown that a small number of SU(3) coupled irreps, those with the largest
C_2 values within the direct product of the proton and neutron SU(3) irreps
with spin 0 and 1 (for even number of particles), and spin 1/2 and 3/2 for (for
odd number of nucleons), are enough to describe the low energy spectra and
B(E2) transition strengths of 21Ne, 23Na and 25Mg. A simple but realistic
Hamiltonian is employed. Results compare favorably both with experimental data
and with full shell model calculations. Limitations and possible improvements
of the schematic Hamiltonian are discussed.

</DOC>
<DOC>
<DOCNO> 152623 </DOCNO>
Nonabelian noncommutative gauge fields and Seiberg-Witten map


  Noncommutative gauge fields (similar to the type that arises in string theory
with background B-fields) are constructed for arbitrary nonabelian gauge groups
with the help of a map that relates ordinary nonabelian and noncommutative
gauge theories (Seiberg-Witten map). As in our previous work we employ
Kontsevich's formality and the concept of equivalent star products. As a
byproduct we obtain a ``Mini Seiberg-Witten map'' that explicitly relates
ordinary abelian and nonabelian gauge fields.

</DOC>
<DOC>
<DOCNO> 85071 </DOCNO>
Class of Eistein-Maxwell Dilatons


  The functional potential formalism is used to analyze stationary axisymmetric
spaces in the Einstein-Maxwell-Dilaton theory. Performing a Legendre
transformation, a ``Hamiltonian''is obtained, which allows to rewrite the
dynamical equations in terms of three complex functions only. Using an ansatz
resembling the one used by the harmonic maps ansatz, we express these three
functions in terms of the harmonic parameters, studying the cases where these
parameters are real, and when they are complex. For each case, the set of
equations in terms of these harmonic parameters is derived, and several classes
of solutions to the Einstein-Maxwell with arbitrary coupling constant to a
dilaton field are presented. Most of the known solutions of charged and
dilatonic black holes are contained as special cases and can be non-trivially
generalized in different ways.

</DOC>
<DOC>
<DOCNO> 99532 </DOCNO>
Determinants of Laplacians in Exterior Domains


  We consider classes of simply connected planar domains which are isophasal,
ie, have the same scattering phase $s(\l)$ for all $\l > 0$. This is a
scattering-theoretic analogue of isospectral domains. Using the heat invariants
and the determinant of the Laplacian, Osgood, Phillips and Sarnak showed that
each isospectral class is sequentially compact in a natural $C$-infinity
topology. In this paper, we show sequential compactness of each isophasal class
of domains. To do this we define the determinant of the exterior Laplacian and
use it together with the heat invariants (the heat invariants and the
determinant being isophasal invariants). We show that the determinant of the
interior and exterior Laplacians satisfy a Burghelea-Friedlander-Kappeler type
surgery formula. This allows a reduction to a problem on bounded domains for
which the methods of Osgood, Phillips and Sarnak can be adapted.

</DOC>
<DOC>
<DOCNO> 10897 </DOCNO>
Quantum Measurement and Entropy Production


  We study the time evolution of a quantum system without classical
counterpart, undergoing a process of entropy increase due to the environment
influence. We show that if the environment-induced decoherence is interpreted
in terms of wave-function collapses, a symbolic sequence can be generated. We
prove that the Kolmogorov-Sinai entropy of this sequence coincides with rate of
von Neumann entropy increase.

</DOC>
<DOC>
<DOCNO> 100020 </DOCNO>
Some Nasty Reflexive Groups


  In "Almost Free Modules, Set-theoretic Methods", Eklof and Mekler raised the
question about the existence of dual abelian groups G which are not isomorphic
to Z+G. Recall that G is a dual group if G ~ D^* for some group D with
D^*=Hom(D,Z). The existence of such groups is not obvious because dual groups
are subgroups of cartesian products Z^D and therefore have very many
homomorphisms into Z. If p is such a homomorphism arising from a projection of
the cartesian product, then D^* ~ ker(p)+Z. In all `classical cases' of groups
D of infinite rank it turns out that D^* ~ ker(p). Is this always the case?
Also note that reflexive groups G in the sense of H.Bass are dual groups
because by definition the evaluation map s:G-->G^{**} is an isomorphism, hence
G is the dual of G^*. Assuming the diamond axiom for aleph_1 we construct a
reflexive torsion-free abelian group of cardinality aleph_1 which is not
isomorphic to Z+G. The result is formulated for modules over countable
principal ideal domains which are not field.

</DOC>
<DOC>
<DOCNO> 11882 </DOCNO>
Conjectures for the microscopic theory of high temperature


  Based on experimental results and our previous theoretical work, a
microscopic theory of high temperature superconductivity is conjectured. In
this conjecture, superconducting and antiferromagnetic long-range orders are
driven by interlayer coupling. Strictly in two dimensions, the microscopic
Hubbard model has an (resonating valence bond) insulator-to-metal transition at
$x=x_{c}$ near optimal doping for zero temperature, leading to a quantum
critical point, and one of the crossover lines is given by the pseudogap
temperature $T^{*}$. We argue that various singular and non-Fermi liquid
properties observed near optimal doping are due to the presence of this quantum
critical point. In our conjecture, the crossover line $T^{*}$ also practically
divides the superconducting region into two, depending on the doping level with
respect to $x_{c}$. For $x \leq x_{c}$ the superconducting state has
significant antiferromagnetic correlations, while for $x > x_{c}$ it has
virtually no antiferromagnetic correlations, thus justifying the conventional
BCS theory based on the noninteracting electrons. Inelastic neutron scattering
resonance and systematically reduced superfluid density in the superconducting
state below $x_{c}$ have their natural explanations in the present scenario.
The present approach supports interlayer pair tunneling model where the
superconducting condensation energy comes from the lowering of the c-axis
kinetic energy in the superconducting state. Comparison of the present scenario
with some of the leading theories based on the Hubbard and $t-J$ models is
given. The generic features of both hole-doped and electron-doped cuprates as
well as heavy-fermion superconductors may be understood in the {\em unified}
framework within the present picture.

</DOC>
<DOC>
<DOCNO> 101907 </DOCNO>
An Introduction to the Neutrosophic Probability Applied in Quantum


  In this paper one generalizes the classical probability and imprecise
probability to the notion of "neutrosophic probability" in order to be able to
model Heisenberg's Uncertainty Principle of a particle's behavior,
Schr"dinger's Cat Theory, and the state of bosons which do not obey Pauli's
Exclusion Principle (in quantum physics). Neutrosophic probability is close
related to neutrosophic logic and neutrosophic set, and etymologically derived
from "neutrosophy".

</DOC>
<DOC>
<DOCNO> 67680 </DOCNO>
Discovery and Identifictation of Extra Gauge Bosons in e^+e^- -> nu


  We examine the sensitivity of the process e+e- -> nu nubar gamma to extra
gauge bosons, Z' and W', which arise in various extensions of the standard
model. The process is found to be sensitive to W' masses up to several TeV,
depending on the model, the center of mass energy, and the assumed integrated
luminosity. If extra gauge bosons were discovered first in other experiments,
the process could also be used to measure Z' nu nubar and W' couplings. This
measurement would provide information that could be used to unravel the
underlying theory, complementary to measurements at the Large Hadron Collider.

</DOC>
<DOC>
<DOCNO> 116245 </DOCNO>
Dream of a Christmas lecture


  We recall the origins of differential calculus from a modern perspective.
This lecture should be a victory song, but the pain makes it to sound more as
an oath for vendetta, coming from Syracuse two milenia before.

</DOC>
<DOC>
<DOCNO> 152202 </DOCNO>
Type-I vacua and brane transmutation


  In a classic paper, Fradkin and Tseytlin showed how magnetic deformations can
be introduced in open strings. In this contribution we review some recent work
on type-I vacua with magnetised branes and describe the role of additional
discrete deformations, related to quantised values of the NS-NS antisymmetric
tensor B_ab.

</DOC>
<DOC>
<DOCNO> 83452 </DOCNO>
Formal Properties of XML Grammars and Languages


  XML documents are described by a document type definition (DTD). An
XML-grammar is a formal grammar that captures the syntactic features of a DTD.
We investigate properties of this family of grammars. We show that every
XML-language basically has a unique XML-grammar. We give two characterizations
of languages generated by XML-grammars, one is set-theoretic, the other is by a
kind of saturation property. We investigate decidability problems and prove
that some properties that are undecidable for general context-free languages
become decidable for XML-languages. We also characterize those XML-grammars
that generate regular XML-languages.

</DOC>
<DOC>
<DOCNO> 117146 </DOCNO>
Electromagnetic energy penetration in the self-induced transparency


  Two scenarios for the penetration of relativistically intense laser radiation
into an overdense plasma, accessible by self-induced transparency, are
presented. For supercritical densities less than 1.5 times the critical one,
penetration of laser energy occurs by soliton-like structures moving into the
plasma. At higher background densities laser light penetrates over a finite
length only, that increases with the incident intensity. In this regime
plasma-field structures represent alternating electron layers separated by
about half a wavelength by depleted regions.

</DOC>
<DOC>
<DOCNO> 40175 </DOCNO>
Asymmetries in the Production of $\Lambda_c^+$ and $\Lambda_c^-$ Baryons


  We present a measurement of asymmetries in the production of $\Lambda_c^+$
and $\Lambda_c^-$ baryons in 500 GeV/c $\pi^-$--nucleon interactions from the
E791 experiment at Fermilab. The asymmetries were measured as functions of
Feynman x ($x_F$) and transverse momentum squared ($p_T^2$) using a sample of
$1819 \pm 62$ $\Lambda_c$'s observed in the decay channel $\Lambda_c \to
pK^-\pi^+$. We observe more $\Lambda_c^+$ than $\Lambda_c^-$ baryons, with an
asymmetry of $(12.7\pm3.4\pm1.3) %$ independent of $x_F$ and $p_T^2$ in our
kinematical range $(-0.1 < x_F < 0.6$ and $0.0 < p_T^2 < 8.0 (GeV/c)^2$). This
$\Lambda_c$ asymmetry measurement is the first with data in both the positive
and negative $x_F$ regions.

</DOC>
<DOC>
<DOCNO> 121397 </DOCNO>
ASCA Observation of an "X-ray Shadow" in the Galactic Plane


  The diffuse X-ray background (DXB) emission near the Galactic plane ($l,b
\sim 25.6^{\circ},0.78^{\circ}$) has been observed with $ASCA$. The observed
region is toward a Galactic molecular cloud which was recently reported to cast
a deep X-ray shadow in the 0.5 $-$ 2.0 keV band DXB. The selection of this
particular region is intended to provide a constraint on the spatial
distribution of the DXB emission along the line of sight: i.e., the molecular
cloud is optically thick at $<$2 keV and so the bulk of the observed soft
X-rays {\it must} originate in the foreground of the cloud, which is at $\sim$3
kpc from the Sun. In the 0.8 $-$ 9.0 keV band, the observed spectrum is
primarily from multiple components of thermal plasmas. We here report a
detection of soft X-ray (0.5 $-$ 2 keV) emission from an $\sim10^{7}$ K thermal
plasma. Comparisons with the {\it ROSAT} data suggest that this soft X-ray
emission is absorbed by $N_H$ = 1 $-$ 3 $\times$ 10$^{21}$ cm$^{-2}$, which
implies a path-length through the soft X-ray emitting regions of $\la$1 kpc
from the Sun.

</DOC>
<DOC>
<DOCNO> 68380 </DOCNO>
Order \alpha^2 corrections to the decay rate of orthopositronium


  Order \alpha^2 corrections to the decay rate of orthopositronium are
calculated in the framework of nonrelativistic QED. The resulting contribution
is found to be in significant disagreement with one set of experimental
measurements though another experiment is in agreement with theory.

</DOC>
<DOC>
<DOCNO> 8338 </DOCNO>
Experimental Critical Current Patterns in Josephson Junction Ladders


  We present an experimental and theoretical study of the magnetic field
dependence of the critical current of Josephson junction ladders. At variance
with the well-known case of a one-dimensional (1D) parallel array of Josephson
junctions the magnetic field patterns display a single minimum even for very
low values of the self-inductance parameter $\beta_{\rm L}$. Experiments
performed changing both the geometrical value of the inductance and the
critical current of the junctions show a good agreement with numerical
simulations. We argue that the observed magnetic field patterns are due to a
peculiar mapping between the isotropic Josephson ladder and the 1D parallel
array with the self-inductance parameter $\beta_{\rm L}^{\rm eff}=\beta_{\rm
L}+2$.

</DOC>
<DOC>
<DOCNO> 120800 </DOCNO>
Hydrodynamic Simulations of the Sunyaev-Zel'dovich effect(s)


  We have performed a sequence of high resolution hydrodynamic simulations of
structure formation in a LCDM model to study the thermal and kinetic
Sunyaev-Zel'dovich (SZ) effects. Including only adiabatic gas physics, we
demonstrate that our simulations for the thermal effect are converged down to
sub-arcminute scales. In this model, the angular power spectrum of CMB
anisotropies induced by the thermal effect peaks at l~10^4, and reaches an
amplitude just below current observational upper limits. Fluctuations due to
the kinetic effect are a factor of ~30 lower in power and peak at slightly
smaller angular scales. We identify individual SZ sources and compute their
counts as a function of source strength and angular size. We present a
preliminary investigation of the consequences of an early epoch of energy
injection which tends to suppress power on small angular scales, while giving
rise to additional power on largescales from the reheated IGM at high redshift.

</DOC>
<DOC>
<DOCNO> 68938 </DOCNO>
Stoponium Search at Photon Linear Collider


  In some supersymmetric extensions of the Standard Model fairly light
superpartner of t-quark is predicted, which may form bound states ({\it
stoponiums}) under certain conditions. We study prospects of search for
stoponium at the future Photon Linear Collider. It is found that this machine
could be the best machine for discovery and study of these resonances at some
scenarios of supersymmetric extension of the Standard Model. In particular, if
the $hh$ decay channel is dominant stoponium could be observed at the beginning
of PLC run with collision energy tuned at the stoponium mass. If this channel
is kinematically closed stoponium could be discovered in $gg$, $\gamma\gamma$
and $ZZ$ decay channels but higher statistics are needed. Effects of the
stoponium-Higgs mixing and degeneracy are briefly discussed.

</DOC>
<DOC>
<DOCNO> 70206 </DOCNO>
Estimate of a Chiral-Odd Contribution to Single Transverse-Spin


  We present an estimate of a chiral-odd contribution to the single
transverse-spin asymmetry in the large-$p_T$ pion production in the
nucleon-nucleon collision. In this contribution the transversity distribution
and the chiral-odd spin-independent twist-3 distribution appear. Because of the
smallness of the corresponding hard cross section, this term turned out to be
negligible in all kinematic regions compared with the chiral-even contribution.

</DOC>
<DOC>
<DOCNO> 70279 </DOCNO>
Complete analysis on the next-to-leading order supersymmetric QCD


  We present a complete next-to-leading-order calculation of the QCD
corrections to $B^0-\bar{B}^0$ ($K^0-\bar{K}^0$) mixing in the framework of the
minimal flavor violating (MFV) supersymmetry. We take into account the
contributions from the gluino and find that the gluino-mediated corrections
modify the LO result obviously even when the mass of gluino $m_{\tilde{g}} \gg
m_{\rm w}$. In general, one cannot neglect gluino contributions.

</DOC>
<DOC>
<DOCNO> 152332 </DOCNO>
Background Independent Open String Field Theory and Constant B-Field


  We calculate the background independent action for bosonic and supersymmetric
open string field theory in a constant B-field. We also determine the tachyon
effective action in the presence of constant B-field.

</DOC>
<DOC>
<DOCNO> 119873 </DOCNO>
The HI mass function in Ursa Major


  A deep blind HI survey of the nearby spiral rich Ursa Major cluster has been
performed with the VLA in parallel with a wide-field R-band imaging campaign of
most VLA fields with the CFHT. The goal is to measure the slope of the HI mass
function down to HI masses of 10^7 Msun as well as the slope of the faint-end
of the luminosity function down to M(R)=-10. The VLA survey sampled 16% of the
Ursa Major cluster volume. Both the HIMF and the LF in Ursa Major are nearly
flat at their faint-ends. No free- floating HI clouds were detected.

</DOC>
<DOC>
<DOCNO> 170347 </DOCNO>
Resonance fluorescence in a band gap material: Direct numerical


  A numerical method of calculating the non-Markovian evolution of a driven
atom radiating into a structured continuum is developed. The formal solution
for the atomic reduced density matrix is written as a Markovian algorithm by
introducing a set of additional, virtual density matrices which follow, to the
level of approximation of the algorithm, all the possible trajectories of the
photons in the electromagnetic field. The technique is perturbative in the
sense that more virtual density matrices are required as the product of the
effective memory time and the effective coupling strength become larger. The
number of density matrices required is given by $3^{M}$ where $M$ is the number
of timesteps per memory time. The technique is applied to the problem of a
driven two-level atom radiating close to a photonic band gap and the
steady-state correlation function of the atom is calculated.

</DOC>
<DOC>
<DOCNO> 12891 </DOCNO>
High frequency conductivity in the quantum Hall effect


  We present high frequency measurements of the diagonal conductivity sigma_xx
of a two dimensional electron system in the integer quantum Hall regime. The
width of the sigma_xx peaks between QHE minima is analyzed within the framework
of scaling theory using both temperature T=100-700 mK and frequency f <= 6 GHz
in a two parameter scaling ansatz. For the plateau transition width we find
scaling behaviour for both its temperature dependence as well as its frequency
dependence. However, the corresponding scaling exponent for temperature
kappa=0.42 significantly differs from the one deduced for frequency scaling
(c=0.6). Additionally we use the high frequency experiments to suppress the
contact resistances that strongly influences DC measurements. We find an
intrinsic critical conductivity sigma_c=0.17e^2/h, virtually independent of
temperature and filling factor, and deviating significantly from the proposed
universal value 0.5e^2/h.

</DOC>
<DOC>
<DOCNO> 100044 </DOCNO>
The loop expansion of the Kontsevich integral, abelian invariants of


  Hidden in the expansion of the Kontsevich integral, graded by loops rather
than by degree, is a new notion of finite type invariants of knots, closely
related to S-equivalence, and with respect to which the Kontsevich integral is
the universal finite type invariant, modulo S-equivalence. In addition, the
2-loop part Q of the Kontsevich integral behaves like an equivariant version of
Casson's invariant, and its ``first derivative'' is given in terms of linking
functions associated to the universal abelian cover of the knot complement. As
a result, we obtain a linear relation among the Casson-Walker invariant of
cyclic branched covers of knots, residues of the Q-function, and the signature
of the knot.

</DOC>
<DOC>
<DOCNO> 123280 </DOCNO>
Changes in the structure of the accretion disc of EX Draconis through


  (Abridged) We report on the analysis of high-speed photometry of the dwarf
nova EX Dra through its outburst cycle with eclipse mapping techniques. The
eclipse maps show evidence of the formation of a one-armed spiral structure in
the disc at the early stages of the outburst and reveal how the disc expands
during the rise until it fills most of the primary Roche lobe at maximum light.
The eclipse maps also suggest the presence of an inward and an outward-moving
heating wave during the rise and an inward-moving cooling wave in the decline.
Our results suggest a systematic deceleration of both the heating and the
cooling waves as they travel across the disc, in agreement with predictions of
the disc instability model. The analysis of the brightness temperature profiles
indicates that most of the disc appears to be in steady-state during quiescence
and at outburst maximum, but not during the intermediate stages. As a general
trend, the mass accretion rate in the outer regions is larger than in the inner
disc on the rising branch, while the opposite holds during the decline branch.
We estimate a mass accretion rate of Mdot= 10^{-8} Msun/yr at outburst maximum
and Mdot= 10^{-9.1} Msun/yr in quiescence. The brightness temperature profile
in quiescence also suggests that the viscosity parameter is high at this stage
which favours the mass-transfer instability model. The uneclipsed light has a
steady component, understood in terms of emission from the red secondary star,
and a variable component that is proportional to the out of eclipse flux and
corresponds to about 3 per cent of the total brightness of the system. The
variable component is interpreted as arising in a disc wind.

</DOC>
<DOC>
<DOCNO> 101071 </DOCNO>
On the eigenproblems of PT-symmetric oscillators


  We consider the non-Hermitian Hamiltonian H=
-\frac{d^2}{dx^2}+P(x^2)-(ix)^{2n+1} on the real line, where P(x) is a
polynomial of degree at most n \geq 1 with all nonnegative real coefficients
(possibly P\equiv 0). It is proved that the eigenvalues \lambda must be in the
sector | arg \lambda | \leq \frac{\pi}{2n+3}. Also for the case
H=-\frac{d^2}{dx^2}-(ix)^3, we establish a zero-free region of the
eigenfunction u and its derivative u^\prime and we find some other interesting
properties of eigenfunctions.

</DOC>
<DOC>
<DOCNO> 10236 </DOCNO>
Depletion potential in hard-sphere mixtures: theory and applications


  We present a versatile density functional approach (DFT) for calculating the
depletion potential in general fluid mixtures. In contrast to brute force DFT,
our approach requires only the equilibrium density profile of the small
particles {\em before} the big (test) particle is inserted. For a big particle
near a planar wall or a cylinder or another fixed big particle the relevant
density profiles are functions of a single variable, which avoids the numerical
complications inherent in brute force DFT. We implement our approach for
additive hard-sphere mixtures. By investigating the depletion potential for
high size asymmetries we assess the regime of validity of the well-known
Derjaguin approximation for hard-sphere mixtures and argue that this fails. We
provide an accurate parametrization of the depletion potential in hard-sphere
fluids which should be useful for effective Hamiltonian studies of phase
behavior and colloid structure.

</DOC>
<DOC>
<DOCNO> 11007 </DOCNO>
Ground State Energy of the One-Component Charged Bose Gas


  The model considered here is the `jellium' model in which there is a uniform,
fixed background with charge density $-e\rho$ in a large volume $V$ and in
which $N=\rho V$ particles of electric charge $+e$ and mass $m$ move --- the
whole system being neutral. In 1961 Foldy used Bogolubov's 1947 method to
investigate the ground state energy of this system for bosonic particles in the
large $\rho$ limit. He found that the energy per particle is $-0.402 r_s^{-3/4}
{me^4}/{\hbar^2}$ in this limit, where $r_s=(3/4\pi \rho)^{1/3}e^2m/\hbar^2$.
Here we prove that this formula is correct, thereby validating, for the first
time, at least one aspect of Bogolubov's pairing theory of the Bose gas

</DOC>
<DOC>
<DOCNO> 116311 </DOCNO>
Condensation of microturbulence-generated shear flows into global modes


  In full flux-surface computer studies of tokamak edge turbulence, a spectrum
of shear flows is found to control the turbulence level and not just the
conventional (0,0)-mode flows. Flux tube domains too small for the large
poloidal scale lengths of the continuous spectrum tend to overestimate the
flows, and thus underestimate the transport. It is shown analytically and
numerically that under certain conditions dominant (0,0)-mode flows independent
of the domain size develop, essentially through Bose-Einstein condensation of
the shear flows.

</DOC>
<DOC>
<DOCNO> 101012 </DOCNO>
Stationary Markov chains with linear regressions


  In a previous paper we determined one dimensional distributions of a
stationary field with linear regressions and quadratic conditional variances
under a linear constraint on the coefficients of the quadratic expression. In
this paper we show that for stationary Markov chains with linear regressions
and quadratic conditional variances the coefficients of the quadratic
expression are indeed tied by a linear constraint which can take only one of
the two alternative forms.

</DOC>
<DOC>
<DOCNO> 101368 </DOCNO>
Ideal Quantum Gases in D-dimensional Space and Power-law Potentials


  We investigate ideal quantum gases in D-dimensional space and confined in a
generic external potential by using the semiclassical approximation. In
particular, we derive density of states, density profiles and critical
temperatures for Fermions and Bosons trapped in isotropic power-law potentials.
Form such results, one can easily obtain those of quantum gases in a rigid box
and in a harmonic trap. Finally, we show that the Bose-Einstein condensation
can set up in a confining power-law potential if and only if ${D/2}+{D/n}>1$,
where $D$ is the space dimension and $n$ is the power-law exponent.

</DOC>
<DOC>
<DOCNO> 68756 </DOCNO>
Double transverse spin asymmetries in vector boson production


  We investigate a helicity non-flip double transverse spin asymmetry in vector
boson production in hadron-hadron scattering, which was first considered by
Ralston and Soper at the tree level. It does not involve transversity functions
and in principle also arises in W-boson production for which we present the
expressions. The asymmetry requires observing the transverse momentum of the
vector boson, but it is not suppressed by explicit inverse powers of a large
energy scale. However, as we will show, inclusion of Sudakov factors causes
suppression of the asymmetry, which increases with energy. Moreover, the
asymmetry is shown to be approximately proportional to x_1 g_1(x_1) x_2 \bar
g_1(x_2), which gives rise to additional suppression at small values of the
light cone momentum fractions. This implies that it is negligible for Z or W
production and is mainly of interest for \gamma^* at low energies. We also
compare the asymmetry with other types of double transverse spin asymmetries
and discuss how to disentangle them.

</DOC>
<DOC>
<DOCNO> 101382 </DOCNO>
Topology of Quadric Bundles


  This paper begins with a description of cohomological invariants of
non-degenerate quadric bundles, in terms of the cohomology rings of the
classifying spaces of the general orthogonal groups. Following this, the Main
Theorem of the paper determines the behavior of these invariants under the
Gysin boundary map, when a quadric bundle degenerates over a divisor.

</DOC>
<DOC>
<DOCNO> 85246 </DOCNO>
Analysis of quantum evaporation process of black holes in the model of


  In the model of Expansive Nondecelerative Universe, black hole cannot totally
evaporate via quantum evaporation process proposed by Hawking. In a limiting
case, an equilibrium of gravitation creation and black hole evaporation can be
reached keeping the surface of its horizon constant. This conclusion is in
accordance with the second law of thermodynamics.

</DOC>
<DOC>
<DOCNO> 11357 </DOCNO>
Role of interchain hopping in two disordered chains of spinless fermions


  The effect of interchain hopping and interaction on Anderson localization has
been investigated for two coupled chains of spinless fermions with nearest
neighbor interaction. Using the renormalization group method, we find that
interchain hopping plays a significant role when the correlation gap induced by
the interplay of interchain hopping and intrachain interaction becomes larger
than the Anderson localization energy scale induced by impurities. The strong
competition between localization and delocalization is examined for attractive
interaction.

</DOC>
<DOC>
<DOCNO> 39663 </DOCNO>
Flavor asymmetry in polarized proton-deuteron Drell-Yan process


  We discuss the possibility of finding polarized antiquark flavor asymmetry in
Drell-Yan processes. We find that the difference between polarized
proton-proton and proton-deuteron Drell-Yan cross sections should provide
valuable information on the polarized flavor asymmetry. Numerical results
indicate that the asymmetry effects are conspicuous especially in the large-x_F
region. Our analysis is important for the transversity distributions because
the flavor asymmetry cannot be found by inclusive lepton scattering and
W-production processes.

</DOC>
<DOC>
<DOCNO> 10887 </DOCNO>
Cluster Derivation of the Parisi Scheme for Disordered Systems


  We propose a general quantitative scheme in which systems are given the
freedom to sacrifice energy equi-partitioning on the relevant time-scales of
observation, and have phase transitions by separating autonomously into ergodic
sub-systems (clusters) with different characteristic time-scales and
temperatures. The details of the break-up follow uniquely from the requirement
of zero entropy for the slower cluster. Complex systems, such as the
Sherrington-Kirkpatrick model, are found to minimise their free energy by
spontaneously decomposing into a hierarchy of ergodically equilibrating degrees
of freedom at different (effective) temperatures. This leads exactly and
uniquely to Parisi's replica symmetry breaking scheme. Our approach, which is
somewhat akin to an earlier one by Sompolinsky, gives new insight into the
physical interpretation of the Parisi scheme and its relations with other
approaches, numerical experiments, and short range models. Furthermore, our
approach shows that the Parisi scheme can be derived quantitatively and
uniquely from plausible physical principles.

</DOC>
<DOC>
<DOCNO> 12523 </DOCNO>
Information Theory based on Non-additive Information Content


  We generalize the Shannon's information theory in a nonadditive way by
focusing on the source coding theorem. The nonadditive information content we
adopted is consistent with the concept of the form invariance structure of the
nonextensive entropy. Some general properties of the nonadditive information
entropy are studied, in addition, the relation between the nonadditivity $q$
and the codeword length is pointed out.

</DOC>
<DOC>
<DOCNO> 101130 </DOCNO>
The Nonstandard Deformation U'_q(so_n) For q a Root of Unity


  We describe properties of the nonstandard q-deformation U'_q(so_n) of the
universal enveloping algebra U(so_n) of the Lie algebra so_n which does not
coincide with the Drinfeld--Jimbo quantum algebra U_q(so_n). In particular, it
is shown that there exists an isomorphism from U'_q(so_n) to U_q(sl_n) and that
finite dimensional irreducible representations of U'_q(so_n) separate elements
of this algebra. Irreducible representations of the algebras U'_q(so_n) for q a
root of unity q^p=1 are given. The main class of these representations act on
p^N-dimensional linear space (where N is a number of positive roots of the Lie
algebra so_n) and are given by r=dim so_n complex parameters. Some classes of
degenerate irreducible representations are also described.

</DOC>
<DOC>
<DOCNO> 118371 </DOCNO>
Water Masers Diagnosing Postshocked Conditions in W49N


  We present spectroscopic results of 146 water maser outbursts in W49 N,
obtained with the Metsahovi radio telescope at 22 GHz. Combining this data with
Gwinn's VLBI results, we were able to fix the free parameters in the shock
model of Hollenbach and McKee and the maser model of Elitzur, Hollenbach, and
McKee. This enabled a straightforward determination of some 20 shock and maser
parameters, among others, the kinetic temperature, postshock density, water
density, water abundance, preshock and postshock magnetic field strengths as
well as the inclination of the mean field with respect to the line of sight. A
step-by-step presentation of our diagnostic method is given and the relation
between observations and model parameters is discussed. One uniquely powerful
outburst feature, referred to as the "big flare feature", showed also the
narrowest linewidth. Observations indicate that the velocity of this feature
lies in the plane of the sky, whereas preshock and postshock magnetic fields
are directed nearly along the line of sight. Consequently, Alfvenic wave
fluctuations along the line of sight, and linewidth, are minimal, and a very
high aspect ratio is achieved. Furthermore, the big flare feature stands out
through its low space velocity, higher temperature (480 K), and larger preshock
magnetic field strength (8.2 mG).

</DOC>
<DOC>
<DOCNO> 119701 </DOCNO>
FUSE Observations of the Galactic and Intergalactic Medium Towards


  We have obtained moderate resolution spectra of the bright QSO H1821+643
(z=0.297) in the wavelength interval 990-1185A with FUSE. Strong, complex OVI
1032 and FeII 1145 absorption arising in gas above several spiral arms and the
outer warp of our Galaxy is detected. We have identified absorption by a high
negative-velocity (-215 km/s) component of OVI, which corresponds to the
limiting velocity of v_LSR = 190+/-20 km/s for Milky Way gas along this line of
sight, assuming corotation of disk and halo gas and a flat rotation curve for
the outer galaxy. We report the detection of four absorbers in the
intergalactic medium, through detections of Lyman beta at z=0.2454 and
z=0.1213, Lyman delta, epsilon, zeta in a system at z=0.2249, CIII 977 at
z=0.1705, and OVI 1032 at z=0.12137. The FUSE data show that the Lyman
absorbers at z=0.225 are composed of 2 components separated by 70 km/s.
Finally, we have observed associated absorption from OIII 832, OIV 787, and
possibly SV 786 at the redshift of the QSO (z= 0.297). NeVIII 770,780 is not
detected in this associated system. When combined with the previous detection
of associated OVI 1032 (Savage et al, 1998), we conclude that this system is a
multiphase absorber, and we discuss the origin of the absorption in this
context.

</DOC>
<DOC>
<DOCNO> 101276 </DOCNO>
Some spherical uniqueness theorems for multiple trigonometric series


  We prove that if a multiple trigonometric series is spherically Abel summable
everywhere to an everywhere finite function $f(x)$ which is bounded below by an
integrable function, then the series is the Fourier series of $f(x)$ if the
coefficients of the multiple trigonometric series satisfy a mild growth
condition. As a consequence, we show that if a multiple trigonometric series is
spherically convergent everywhere to an everywhere finite integrable function
$f(x)$, then the series is the Fourier series of $f(x)$. We also show that a
singleton is a set of uniqueness. These results are generalizations of a recent
theorem of J. Bourgain and some results of V. Shapiro.

</DOC>
<DOC>
<DOCNO> 84229 </DOCNO>
Active controls in interferometric detectors of gravitational waves:


  The operation of an interferometer for gravitational waves detection requires
sophisticated feedback controls in many parts of the apparatus. The aim of this
lecture is to introduce the types of problems to be faced in this line of
research. The attention is focused on the "inertial damping" of the test mass
suspension of the VIRGO interferometer (the superattenuator): it is a
multidimensional local control aimed to reduce the residual motion of the
suspended mirror associated to the normal modes of the suspension. Its
performance is very important for the locking of the interferometer.

</DOC>
<DOC>
<DOCNO> 151919 </DOCNO>
Non-Semisimple Gaugings of D=5 N=8 Supergravity and FDA.s


  We reformulate maximal D=5 supergravity in the consistent approach uniquely
based on Free Differential Algebras and the solution of their Bianchi
identities (= rheonomic method). In this approach the lagrangian is unnecessary
since the field equations follow from closure of the supersymmetry algebra.
This enables us to explicitly construct the non-compact gaugings corresponding
to the non--semisimple algebras CSO(p,q,r), irrespectively from the existence
of a lagrangian. The use of Free Differential Algebras is essential to clarify,
within a cohomological set up, the dualization mechanism between one-forms and
two-forms. Our theories contain 12-r self-dual two-forms and 15+r gauge
vectors, r of which are abelian and neutral. These theories, whose existence is
proved and their supersymmetry algebra constructed hereby, have potentially
interesting properties in relation with domain wall solutions and the trapping
of gravity.

</DOC>
<DOC>
<DOCNO> 102397 </DOCNO>
The asymptotic determinant of the discrete Laplacian


  We compute the asymptotic determinant of the discrete Laplacian on a
simply-connected rectilinear region in R^2. As an application of this result,
we prove that the growth exponent of the loop-erased random walk in Z^2 is 5/4.

</DOC>
<DOC>
<DOCNO> 102832 </DOCNO>
The vertex ideal of a lattice


  We introduce a monomial ideal whose standard monomials encode the vertices of
all fibers of a lattice. We study the minimal generators, the radical, the
associated primes and the primary decomposition of this ideal, as well as its
relation to initial ideals of lattice ideals.

</DOC>
<DOC>
<DOCNO> 84906 </DOCNO>
Cosmic Inflation


  I review the current status of the theory of Cosmic Inflation. My discussion
covers the motivation and implementation of the idea, as well as an analysis of
recent successes and open questions. There is a special discussion of the
physics of ``cosmic coherence'' in the primordial perturbations. The issue of
coherence is at the heart of much of the success inflation theory has achieved
at the hands of the new microwave background data. While much of this review
should be useful to anyone seeking to update their knowledge of inflation
theory, I have also made a point of including basic material directed at
students just starting research.

</DOC>
<DOC>
<DOCNO> 83185 </DOCNO>
Exact Phase Transitions in Random Constraint Satisfaction Problems


  In this paper we propose a new type of random CSP model, called Model RB,
which is a revision to the standard Model B. It is proved that phase
transitions from a region where almost all problems are satisfiable to a region
where almost all problems are unsatisfiable do exist for Model RB as the number
of variables approaches infinity. Moreover, the critical values at which the
phase transitions occur are also known exactly. By relating the hardness of
Model RB to Model B, it is shown that there exist a lot of hard instances in
Model RB.

</DOC>
<DOC>
<DOCNO> 150449 </DOCNO>
Green-Schwarz String in AdS_5 x S^5: Semiclassical Partition Function


  A systematic approach to the study of semiclassical fluctuations of strings
in AdS_5 x S^5 based on the Green-Schwarz formalism is developed. We show that
the string partition function is well defined and finite. Issues related to
different gauge choices are clarified. We consider explicitly several cases of
classical string solutions with the world surface ending on a line, on a circle
or on two lines on the boundary of AdS. The first example is a BPS object and
the partition function is one. In the third example the determinants we derive
should give the first corrections to the Wilson loop expectation value in the
strong coupling expansion of the n=4 SYM theory at large N.

</DOC>
<DOC>
<DOCNO> 122059 </DOCNO>
Radial and Transverse Velocities of Nearby Galaxies


  Analysis of the peculiar velocities of galaxies should take account of the
uncertainties in both redshifts and distances. We show how this can be done by
a numerical application of the action principle. The method is applied to an
improved catalog of the galaxies and tight systems of galaxies within
4$h_{75}^{-1}$ Mpc, supplemented with a coarser sample of the major
concentrations at 4$h_{75}^{-1}$ Mpc to 20$h_{75}^{-1}$ Mpc distance. Inclusion
of this outer zone improves the fit of the mass tracers in the inner zone to
their measured redshifts and distances, yielding best fits with reduced $\chi
^2$ in redshift and distance in the range 1.5 to 2. These solutions are based
on the assumption that the galaxies in and near the Local Group trace the mass,
and a powerful test would be provided by observations of proper motions of the
nearby galaxies. Predicted transverse galactocentric velocities of some of the
nearby galaxies are confined to rather narrow ranges of values, and are on the
order of 100 km~s$^{-1}$, large enough to be detected and tested by the
proposed SIM and GAIA satellite missions.

</DOC>
<DOC>
<DOCNO> 85300 </DOCNO>
Antisymmetrised 2p-forms generalising curvature 2-forms II: a


  The p-hierarchy of Schwarzschild type metrics obtained in a preceing paper is
generalised here to a corresponding Reissner-Nordstrom (RN) type hierarchy in
the presence of a point charge q in d-dimensions. Certain special features
arising, concerning the horizons and the interior region, are discussed.

</DOC>
<DOC>
<DOCNO> 122018 </DOCNO>
Spatial Structure and Periodicity in the Universe


  We analyze the possibility that the spatial periodicity of 128 h^{-1}Mpc in
the galaxy count number observed recently in deep pencil-beam surveys could be
explained by the mere existence of structure with the appropriate scale in the
galaxy distribution in the Universe. We simulate a universe where the
distribution of galaxies has an intrinsic length scale and then investigate the
probability of observing in a given direction a spatial periodicity similar to
that observed in the pencil-beam surveys of the galactic polar regions. A
statistical analysis shows that this probability is of the order of 10^{-8}, a
value which excludes the afore mentioned explanation. This result contrasts
with the estimates based on Voronoi foam models which yield probabilities of
the order 10^{-1} - 10^{-2}. The conclusion that emerges from these studies put
together with the present one, is that although they can be obtained in some
models, the presence of an intrinsic scale in the structure is not sufficient
to achieve reasonable probabilities for observation of the detected
periodicities.

</DOC>
<DOC>
<DOCNO> 122495 </DOCNO>
The Unusual Spectral Energy Distribution of a Galaxy Previously Reported


  Observations of distant galaxies are important both for understanding how
galaxies form and for probing the physical conditions of the universe at the
earliest epochs. It is, however, extremely difficult to identify galaxies at
redshift z>5, because these galaxies are faint and exhibit few spectral
features. In a previous work, we presented observations that supported the
identification of a galaxy at redshift z = 6.68 in a deep STIS field. Here we
present new ground-based photometry of the galaxy. We find that the galaxy
exhibits moderate detections of flux in the optical B and V images that are
inconsistent with the expected absence of flux at wavelength shortward of the
redshifted Lyman-alpha emission line of a galaxy at redshift z>5. In addition,
the new broad-band imaging data not only show flux measurements of this galaxy
that are incompatible with the previous STIS measurement, but also suggest a
peculiar spectral energy distribution that cannot be fit with any galaxy
spectral template at any redshift. We therefore conclude that the redshift
identification of this galaxy remains undetermined.

</DOC>
<DOC>
<DOCNO> 99663 </DOCNO>
Classical and Quantum Probability


  We survey the development of probability from 1900, starting with Bachelier's
theory of speculation. Fisher information appears in the theory of estimation.
We touch on Brownian motion, and the Wiener integral. The Ito calculus, and its
relation to to the heat equation, is mentioned. Quantum theory is introduced as
a generalisation of probability, rather than of mechanics. The weakness of
attempts to describe quantum theory in terms of hidden variables is explained,
by a simple proof of Bell's inequality.
  Quantum versions of the Langevin equation are discussed, and the theory of
continuous tensor products is used to give a possible quantum version. The
quantum stochastic calculus of Barnett, Wilde and the author, as well as that
of Parthasarathy and Hudson, is introduced.

</DOC>
<DOC>
<DOCNO> 83233 </DOCNO>
Multimethods and separate static typechecking in a language with


  The goal of this paper is the description and analysis of multimethod
implementation in a new object-oriented, class-based programming language
called OOLANG. The implementation of the multimethod typecheck and selection,
deeply analyzed in the paper, is performed in two phases in order to allow
static typechecking and separate compilation of modules. The first phase is
performed at compile time, while the second is executed at link time and does
not require the modules' source code. OOLANG has syntax similar to C++; the
main differences are the absence of pointers and the realization of
polymorphism through subsumption. It adopts the C++ object model and supports
multiple inheritance as well as virtual base classes. For this reason, it has
been necessary to define techniques for realigning argument and return value
addresses when performing multimethod invocations.

</DOC>
<DOC>
<DOCNO> 9395 </DOCNO>
Resonant Activation Phenomenon for Non-Markovian Potential-Fluctuation


  We consider a generalization of the model by Doering and Gadoua to
non-Markovian potential-switching generated by arbitrary renewal processes. For
the Markovian switching process, we extend the original results by Doering and
Gadoua by giving a complete description of the absorption process. For all
non-Markovian processes having the first moment of the waiting time
distributions, we get qualitatively the same results as in the Markovian case.
However, for distributions without the first moment, the mean first passage
time curves do not exhibit the resonant activation minimum. We thus come to the
conjecture that the generic mechanism of the resonant activation fails for
fluctuating processes widely deviating from Markovian.

</DOC>
<DOC>
<DOCNO> 40289 </DOCNO>
A Measurement of the Rate of Charm Production in W Decays


  Using data recorded at centre-of-mass energies around 183 GeV and 189 GeV
with the OPAL detector at LEP, the fundamental coupling of the charm quark to
the W boson has been studied. The ratio Rc^W = Gamma(W -> cX)/Gamma(W ->
hadrons) has been measured from jet properties, lifetime information, and
leptons produced in charm decays. A value compatible with the Standard Model
expectation of 0.5 is obtained: Rc^W = 0.481 +- 0.042(stat.) +- 0.032(syst.).
By combining this result with measurements of the W boson total width and
hadronic branching ratio, the magnitude of the CKM matrix element Vcs is
determined to be |Vcs| = 0.969 +- 0.058.

</DOC>
<DOC>
<DOCNO> 119606 </DOCNO>
On the origin of the difference between the runaway velocities of the


  The recent finding by Chevalier & Ilovaisky (1998) that OB-supergiant X-ray
binaries have relatively large runaway velocities whereas Be/X-ray binaries
have low runaway velocities, provides confirmation of the current models for
the formation of these two types of systems. These predict a difference in
runaway velocity of an order of magnitude. This difference basically results
from the variation of the fractional helium core mass as a function of stellar
mass, in combination with the conservation of orbital angular momentum during
the mass transfer phase that preceded the formation of the compact object in
the system. This combination results into: (i) Systematically narrower
pre-supernova orbits in the OB-supergiant systems than in the Be-systems, and
(ii) A larger fractional amount of mass ejected in the supernovae in high-mass
systems relative to systems of lower mass. Regardless of possible kick
velocities imparted to neutron stars at birth, this combination leads to a
considerable difference in average runaway velocity between these two groups.
The observed low runaway velocities of the Be/X-ray binaries confirm that in
most cases not more than 1 to 2Msun was ejected in the supernovae that produced
their neutron stars. This, in combination with the --on average-- large orbital
eccentricities of these systems, indicates that their neutron stars must have
received a velocity kick in the range 60 - 250 km/s at birth.

</DOC>
<DOC>
<DOCNO> 100505 </DOCNO>
Refined q-trinomial coefficients and character identities


  A refinement of the q-trinomial coefficients is introduced, which has a very
powerful iterative property. This ``T-invariance'' is applied to derive new
Virasoro character identities related to the exceptional simply-laced Lie
algebras E_6,E_7 and E_8.

</DOC>
<DOC>
<DOCNO> 101020 </DOCNO>
Lefschetz type pencils on contact manifolds


  We define the concept of Lefschetz contact pencil and we show the existence
of such structures on any contact manifold. The main idea of the proof is a
generalization of the Donaldson arguments used in the symplectic case. We will
analyze some of the applications of such existence theorem for the topology of
approximately holomorphic contact submanifolds.

</DOC>
<DOC>
<DOCNO> 39614 </DOCNO>
Standard Model Physics at LEP


  Selected topics on precision tests of the Standard Model of the Electroweak
and the Strong Interaction at the LEP $e^+e^-$ collider are presented,
including an update of the world summary of measurements of $\alpha_s$,
representing the state of knowledge of summer 1999. This write-up of lecture
notes consists of a reproduction of slides, pictures and tables, supplemented
by a short descriptive text and a list of relevant references.

</DOC>
<DOC>
<DOCNO> 152006 </DOCNO>
Interference phenomena, chiral bosons and Lorentz invariance


  We have studied the theory of gauged chiral bosons and proposed a general
theory, a master action, that encompasses different kinds of gauge field
couplings in chiral bosonized theories with first-class chiral constraints. We
have fused opposite chiral aspects of this master action using the soldering
formalism and applied the final action to several well known models. The
Lorentz rotation permitted us to fix conditions on the parameters of this
general theory in order to preserve the relativistic invariance. We also have
established some conditions on the arbitrary parameter concerned in a chiral
Schwinger model with a generalized constraint, investigating both covariance
and Lorentz invariance. The results obtained supplements the one that shows the
soldering formalism as a new method of mass generation.

</DOC>
<DOC>
<DOCNO> 40282 </DOCNO>
Study of the process e+e- to pi+pi-pi+pi-pi0 with CMD-2 detector


  The process e+e- to pi+ pi- pi+ pi- pi0 has been studied in the center of
mass energy range 1280 -- 1380 MeV using 3.0 1/pb of data collected with the
CMD-2 detector in Novosibirsk. Analysis shows that the cross section of the
five pion production is dominated by the contributions of the eta pi+pi- and
omega pi+pi- intermediate states.

</DOC>
<DOC>
<DOCNO> 8357 </DOCNO>
Charge-density waves in the Hubbard chain: evidence for 4k_F instability


  Charge density waves in the Hubbard chain are studied by means of
finite-temperature Quantum Monte Carlo simulations and Lanczos diagonalizations
for the ground state. We present results both for the charge susceptibilities
and for the charge structure factor at densities \rho=1/6 and 1/3; for \rho=1/2
(quarter filled) we only present results for the charge structure factor. The
data are consistent with a 4k_F instability dominating over the 2k_F one, at
least for sufficiently large values of the Coulomb repulsion, U. This can only
be reconciled with the Luttinger liquid analyses if the amplitude of the 2k_F
contribution vanishes above some U^*(\rho).

</DOC>
<DOC>
<DOCNO> 152363 </DOCNO>
The metric and strong coupling limit of the M5-brane


  We find the analogue of the Boillat metric of Born-Infeld theory for the
M5-brane. We show that it provides the propagation cone of {\sl all} 5-brane
degrees. In an arbitrary background field, this cone never lies outside the
Einstein cone. An energy momentum tensor for the three-form is defined and
shown to satisfy the Dominant Energy Condition. The theory is shown to be well
defined for all values of the magnetic field but there is a limiting electric
field strength. We consider the strong coupling limit of the M5-brane and show
that the corresponding theory is conformally invariant and admits infinitely
many conservation laws. On reduction to the Born-Infeld case this agrees with
the work of Bia{\l}nicki-Birula.

</DOC>
<DOC>
<DOCNO> 170473 </DOCNO>
Quantum Clock Synchronisation based on entangled photon pairs


  We discuss the possibility of synchronising two atomic clocks exchanging
entangled photon pairs through a quantum channel. A proposal for implementing
practically such a scheme is discussed.

</DOC>
<DOC>
<DOCNO> 119769 </DOCNO>
The parallax distorsion via a weak microlensing effect


  Parallax measurements allow distances to celestial objects to be determined.
Coupled with measurement of their position on the celestial sphere, it gives a
full three-dimensional picture of the location of the objects relative to the
observer. The distortion of the parallax value of a remote source affected by a
weak microlensing is considered. This means that the weak microlensing leads to
distortion of the distance scale. It is shown that the distortions to appear
may change strongly the parallax values in case they amount to several
microseconds of arc. In particular, at this accuracy many measured values of
the parallaxes must be negative.

</DOC>
<DOC>
<DOCNO> 12874 </DOCNO>
Measurements of the instantaneous velocity difference and local velocity


  New optical arrangements with two single-mode input fibers and a fiber-optic
coupler are devised to measure the instantaneous velocity difference and local
velocity. The fibers and the coupler are polarization-preserving to guarantee a
high signal-to-noise ratio. When the two input fibers are used to collect the
scattered light with the same momentum transfer vector but from two spatially
separated regions in a flow, the obtained signals interfere when combined via
the fiber-optic coupler. The resultant light received by a photomultiplier tube
contains a cross-beat frequency proportional to the velocity difference between
the two measuring points. If the two input fibers are used to collect the
scattered light from a common scattering region but with two different momentum
transfer vectors, the resultant light then contains a self-beat frequency
proportional to the local velocity at the measuring point. The experiment shows
that both the cross-beat and self-beat signals are large and the standard laser
Doppler signal processor can be used to measure the velocity difference and
local velocity in real time. The new technique will have various applications
in the general area of fluid dynamics.

</DOC>
<DOC>
<DOCNO> 10291 </DOCNO>
Side-gate modulation of critical current in mesoscopic Josephson


  We study the normal state conductance and the Josephson current in a
superconductor-2DEG-superconductor structure where the size/shape of the
2DEG-region can be modified by an additional side-gate electrode. The
considered transport properties follow from the retarded Green function which
we compute by employing a tight-binding-like representation of the Hamiltonian
in the 2DEG region. Our model studies offer a qualitative demonstration of the
recently observed effects caused by side-gate modulation.

</DOC>
<DOC>
<DOCNO> 122498 </DOCNO>
An Optical Counterpart to the Anomalous X-ray Pulsar 4U 0142+61


  The energy source of the anomalous X-ray pulsars is not well understood,
hence their designation as anomalous. Unlike binary X-ray pulsars, no
companions are seen, so the energy cannot be supplied by accretion of matter
from a companion star. The loss of rotational energy, which powers radio
pulsars, is insufficient to power AXPs. Two models are generally considered:
accretion from a large disk left over from the birth process, or decay of a
very strong magnetic field (10^15 G) associated with a 'magnetar'. The lack of
counterparts at other wavelengths has hampered progress in our understanding of
these objects. Here, we present deep optical observations of the field around
4U 0142+61, which is the brightest AXP in X-rays. We find an object with
peculiar optical colours at the position of the X-ray source, and argue that it
is the optical counterpart. The optical emission is too faint to admit the
presence of a large accretion disk, but may be consistent with magnetospheric
emission from a magnetar.

</DOC>
<DOC>
<DOCNO> 118020 </DOCNO>
The Apparent and Intrinsic Shape of the APM Galaxy Clusters


  We estimate the distribution of intrinsic shapes of APM galaxy clusters from
the distribution of their apparent shapes. We measure the projected cluster
ellipticities using two alternative methods. The first method is based on
moments of the discrete galaxy distribution while the second is based on
moments of the smoothed galaxy distribution. We study the performance of both
methods using Monte Carlo cluster simulations covering the range of APM cluster
distances and including a random distribution of background galaxies. We find
that the first method suffers from severe systematic biases, whereas the second
is more reliable. After excluding clusters dominated by substructure and
quantifying the systematic biases in our estimated shape parameters, we recover
a corrected distribution of projected ellipticities. We use the non-parametric
kernel method to estimate the smooth apparent ellipticity distribution, and
numerically invert a set of integral equations to recover the corresponding
distribution of intrinsic ellipticities under the assumption that the clusters
are either oblate or prolate spheroids. The prolate spheroidal model fits the
APM cluster data best.

</DOC>
<DOC>
<DOCNO> 151730 </DOCNO>
Induced gravity with complex metric field


  The possible existence of a complex metric tensor field is studied. We show
that an effective scalar field is induced by an overall phase component of the
complex metric tensor. The corresponding gauge field is shown to be a tachyon.
Possible implications of this scalar field to the no hair theorem in a
spherically symmetric space is also analyzed. We also study its impact on the
evolution of the early universe.

</DOC>
<DOC>
<DOCNO> 14023 </DOCNO>
Fermionic R-Operator and Algebraic Structure of 1D Hubbard Model: Its


  The algebraic structure of the 1D Hubbard model is studied by means of the
fermionic R-operator approach. This approach treats the fermion models directly
in the framework of the quantum inverse scattering method. Compared with the
graded approach, this approach has several advantages. First, the global
properties of the Hamiltonian are naturally reflected in the algebraic
properties of the fermionic R-operator. We want to note that this operator is a
local operator acting on fermion Fock spaces. In particular, SO(4) symmetry and
the invariance under the partial particle hole transformation are discussed.
Second, we can construct a genuinely fermionic quantum transfer transfer matrix
(QTM) in terms of the fermionic R-operator. Using the algebraic Bethe Ansatz
for the Hubbard model, we diagonalize the fermionic QTM and discuss its
properties.

</DOC>
<DOC>
<DOCNO> 83388 </DOCNO>
Cluster Computing: A High-Performance Contender


  When you first heard people speak of Piles of PCs, the first thing that came
to mind may have been a cluttered computer room with processors, monitors, and
snarls of cables all around. Collections of computers have undoubtedly become
more sophisticated than in the early days of shared drives and modem
connections. No matter what you call them, Clusters of Workstations (COW),
Networks of Workstations (NOW), Workstation Clusters (WCs), Clusters of PCs
(CoPs), clusters of computers are now filling the processing niche once
occupied by more powerful stand-alone machines. This article discusses the need
for cluster computing technology, Technologies, Components, and Applications,
Supercluster Systems and Issues, The Need for a New Task Force, and Cluster
Computing Educational Resources.

</DOC>
<DOC>
<DOCNO> 7767 </DOCNO>
Microwave Electrodynamics of the Electron-Doped Cuprate Superconductors


  The pairing state symmetry of the electron-doped cuprate superconductors is
thought to be s-wave in nature, in contrast with their hole-doped counterparts
which exhibit a d-wave symmetry. We re-examine this issue based on recent
improvements in our electron-doped materials and our measurement techniques. We
report microwave cavity perturbation measurements of the temperature dependence
of the penetration depth of Pr_(2-x)Ce_(x)CuO_(4-y) and Nd_(2-x)Ce_(x)CuO_(4-y)
crystals. Our data strongly suggest that the pairing symmetry in these
materials is not s-wave.

</DOC>
<DOC>
<DOCNO> 100762 </DOCNO>
Application of Lie Transformation Group Methods to Classical Theories of


  In the present paper, a class of partial differential equations related to
various plate and rod problems is studied by Lie transformation group methods.
A system of equations determining the generators of the admitted point Lie
groups (symmetries) is derived. A general statement of the associated
group-classification problem is given. A simple intrinsic relation is deduced
allowing to recognize easily the variational symmetries among the ''ordinary''
symmetries of a self-adjoint equation of the class examined. Explicit formulae
for the conserved currents of the corresponding (via Noether's theorem)
conservation laws are suggested. Solutions of group-classification problems are
presented for subclasses of equations of the foregoing type governing stability
and vibration of plates, rods and fluid conveying pipes resting on variable
elastic foundations and compressed by axial forces. The obtained
group-classification results are used to derive conservation laws and
group-invariant solutions readily applicable in plate statics or rod dynamics.

</DOC>
<DOC>
<DOCNO> 9776 </DOCNO>
Instabilities and self-socillations in atomic four-wave mixing


  The development of integrated, waveguide-based atom optical devices requires
a thorough understanding of nonlinear matter-wave mixing processes in confined
geometries. This paper analyzes the stability of counterpropagating
two-component Bose-Einstein condensates in such a geometry. The steady state
field equations of this system are solved analytically, predicting a
multivalued relation between the input and output field intensities. The
spatio-temporal linear stability of these solutions is investigated
numerically, leading to the prediction of a self-oscillation threshold that can
be expressed in terms of a matter-wave analog of the Fresnel number in optics.

</DOC>
<DOC>
<DOCNO> 81007 </DOCNO>
Topics in Non-Perturbative QCD


  General aspects of non-perturbative field theory are discussed.The definition
of condensates is analysed.Mechanisms of color confinement are rewieved.

</DOC>
<DOC>
<DOCNO> 10101 </DOCNO>
Exact Eigenstates for Repulsive Bosons in Two Dimensions


  We consider a model of $N$ two-dimensional bosons in a harmonic potential
with weak repulsive delta-function interactions. We show analytically that, for
angular momentum $L\le N$, the elementary symmetric polynomials of particle
coordinates measured from the center of mass are exact eigenstates with energy
$N(N-L/2-1)$. Extensive numerical analysis confirms that these are actually the
ground states, but we are currently unable to prove this analytically. The
special case $L=N$ can be thought of as the generalisation of the usual
superfluid one-vortex state to Bose-Einstein condensates in a trap.

</DOC>
<DOC>
<DOCNO> 123031 </DOCNO>
Variability in ultra cool dwarfs: evidence for the evolution of surface


  We present photometric light curves for a sample of 21 ultra cool M and L
dwarfs in the field and in the young open clusters sigma Orionis and the
Pleiades. Evidence for variability with RMS amplitudes (in the I band) of 0.01
to 0.055 magnitudes on timescales of 0.4 to 100 hours is discovered in half of
these objects. Power spectral analysis using the CLEAN algorithm was performed
to search for evidence of periodic variability. Some objects show strong
periodicities at around a few hours, which could be due to rotational
modulation of the light curve by surface features. However, several objects do
not have any significant periodicities to explain their variability. The vsini
values of a similar population of objects makes it very likely that our time
sampling was sensitive to the expected range of rotation periods, and
simulations show that we would have detected these if they were caused by
long-lived surface features. We argue that this absence of periodicity is due
to the evolution of the brightness, and presumably also the physical size, of
surface features on timescales of a few to a few tens of hours. This is
supported in the case of 2M1145 for which two light curves have been obtained
one year apart and show no common periodicity. The surface features could
plausibly be photospheric dust clouds or magnetically-induced spots. The
recently observed decline in chromospheric activity for late type M and L
dwarfs hints towards the former explanation for at least our later-type
objects. Furthermore, our sample suggests that variability to be more common in
objects later than M9, indicating that the variability may be related to dust
formation. One light curve shows a brief, but significant, dip, which could be
a short-lived feature or possibly an eclipse by a companion. (abridged)

</DOC>
<DOC>
<DOCNO> 99655 </DOCNO>
Rolle's theorem is either false or trivial in infinite-dimensional


  We prove the following new characterization of $C^p$ (Lipschitz) smoothness
in Banach spaces. An infinite-dimensional Banach space $X$ has a $C^p$ smooth
(Lipschitz) bump function if and only if it has another $C^p$ smooth
(Lipschitz) bump function $f$ such that $f'(x)\neq 0$ for every point $x$ in
the interior of the support of $f$ (that is, $f$ does not satisfy Rolle's
theorem). Moreover, the support of this bump can be assumed to be a smooth
starlike body. As a by-product of the proof of this result we also obtain other
useful characterizations of $C^p$ smoothness related to the existence of a
certain kind of deleting diffeomorphisms, as well as to the failure of
Brouwer's fixed point theorem even for smooth self-mappings of starlike bodies
in all infinite-dimensional spaces. Finally, we study the structure of the set
of gradients of bump functions in the Hilbert space $\ell_2$, and as a
consequence of the failure of Rolle's theorem in infinite dimensions we get the
following result. The usual norm of the Hilbert space $\ell_2$ can be uniformly
approximated by $C^1$ smooth Lipschiz functions $\psi$ so that the cones
generated by the sets of derivatives $\psi'(\ell_{2})$ have empty interior.
This implies that there are $C^1$ smooth Lipschitz bumps in $\ell_{2}$ so that
the cones generated by their sets of gradients have empty interior.

</DOC>
<DOC>
<DOCNO> 169909 </DOCNO>
EPR Test with Photons and Kaons: Analogies


  We present a unified formalism describing EPR test using spin 1/2 particles,
photons and kaons. This facilitates the comparison between existing experiments
using photons and kaons. It underlines the similarities between birefringence
and polarization dependent losses that affects experiments using optical fibers
and mixing and decay that are intrinsic to the kaons. We also discuss the
limitation these two characteristics impose on the testing of Bell's
inequality.

</DOC>
<DOC>
<DOCNO> 12635 </DOCNO>
Tighter Decoding Reliability Bound for Gallager's Error-Correcting Code


  Statistical physics is employed to evaluate the performance of
error-correcting codes in the case of finite message length for an ensemble of
Gallager's error correcting codes. We follow Gallager's approach of
upper-bounding the average decoding error rate, but invoke the replica method
to reproduce the tightest general bound to date, and to improve on the most
accurate zero-error noise level threshold reported in the literature. The
relation between the methods used and those presented in the information theory
literature are explored.

</DOC>
<DOC>
<DOCNO> 150949 </DOCNO>
Brane Theory Solitons


  Field theories that describe {\sl small} fluctuations of branes are limits of
`brane theories' that describe {\sl large} fluctuations. In particular,
supersymmetric sigma-models arise in this way. These lectures discuss the
soliton solutions of the associated `brane theories' and their relation to
calibrations.

</DOC>
<DOC>
<DOCNO> 70652 </DOCNO>
QCD corrections to lifetime differences of B_s mesons


  The calculation of QCD corrections to the width difference Delta Gamma in the
B_s meson system is presented. The next-to-leading order corrections reduce the
dependence on the renormalization scale significantly and allow for a
meaningful use of hadronic matrix elements from lattice gauge theory. At
present the uncertainty of the lattice calculations limits the prediction of
Delta Gamma. The presented work has been performed in collaboration with Martin
Beneke, Gerhard Buchalla, Christoph Greub and Alexander Lenz.

</DOC>
<DOC>
<DOCNO> 12250 </DOCNO>
Renormalization group and perfect operators for stochastic differential


  We develop renormalization group methods for solving partial and stochastic
differential equations on coarse meshes. Renormalization group transformations
are used to calculate the precise effect of small scale dynamics on the
dynamics at the mesh size. The fixed point of these transformations yields a
perfect operator: an exact representation of physical observables on the mesh
scale with minimal lattice artifacts. We apply the formalism to simple
nonlinear models of critical dynamics, and show how the method leads to an
improvement in the computational performance of Monte Carlo methods.

</DOC>
<DOC>
<DOCNO> 71057 </DOCNO>
Flavour-dependent SUSY phases and CP asymmetry in B -> X_s gamma decays


  We study the direct CP asymmetry in B -> X_s gamma decay in SUSY models with
non-universal A-terms. We show that the flavour-dependent phases of the
A-terms, unlike the flavour-independent ones, can give rise too large
contribution to the CP asymmetry while respecting the experimental bounds on
the branching ratio of B -> X_s gamma decay and the electric dipole moments of
the electron and neutron. The CP asymmetry of this decay is predicted to be
much larger than the standard model prediction in a wide region of the
parameter space. In particular, it can be of order 10-15% which can be
accessible at B factories.

</DOC>
<DOC>
<DOCNO> 121728 </DOCNO>
First Order Kaon Condensation in Neutron Stars: Finite Size Effects in


  We study the role of Coulomb and surface effects on the phase transition from
dense nuclear matter to a mixed phase of nuclear and kaon-condensed matter. We
calculate corrections to the bulk calculation of the equation of state (EOS)
and the critical density for the transition by solving explicitly for
spherical, cylindrical, and planar structures. The importance of Debye
screening in the determination of the charged particle profiles is studied in
some detail. We find that the surface and Coulomb contributions to the energy
density are small, but that they play an important role in the determination of
the critical pressure for the transition, as well as affecting the size and
geometry of favored structures. This changes the EOS over a wide range of
pressure and consequently increases the maximum mass by about 0.1 solar masses.
Implications for transport properties of the mixed phase are also discussed.

</DOC>
<DOC>
<DOCNO> 117311 </DOCNO>
Anisotropic charge displacement supporting isolated photorefractive


  The strong asymmetry in charge distribution supporting a single
non-interacting spatial needle soliton in a paraelectric photorefractive is
directly observed by means of electroholographic readout. Whereas in trapping
conditions a quasi-circular wave is supported, the underlying double-dipolar
structure can be made to support two distinct propagation modes.

</DOC>
<DOC>
<DOCNO> 116411 </DOCNO>
A new volatility term in the theory of options with transaction costs


  The introduction of transaction costs into the theory of option pricing could
lead not only to the change of return for options, but also to the change of
the volatility. On the base of assumption of the portfolio analysis, a new
equation for option pricing with transaction costs is derived. A new solution
for the option price is obtained for the time close to expiration date.

</DOC>
<DOC>
<DOCNO> 120180 </DOCNO>
Accurate Determination of the Mass Distribution in Spiral Galaxies: II.


  New high resolution CFHT Fabry-Perot data, combined with published VLA 21 cm
observations are used to determine the mass distribution of NGC 3109 and IC
2574. The multi-wavelength rotation curves allow to test with confidence
different dark halo functional forms from the pseudo-isothermal sphere to some
popular halo distributions motivated by N-body simulations. It appears that
density distribution with an inner logarithmic slope <= -1 are very hard to
reconcile with rotation curves of late type spirals. Modified Newtonian
Dynamics (MOND) is also considered as a potential solution to missing mass and
tested the same way. The new higher resolution data show that MOND can
reproduce in details the rotation curve of IC 2574 but confirm its difficulty
to fit the kinematics of NGC 3109.

</DOC>
<DOC>
<DOCNO> 8586 </DOCNO>
Effects of Electron-Electron Scattering on Electron-Beam Propagation in


  We have studied experimentally and theoretically the influence of
electron-electron collisions on the propagation of electron beams in a
two-dimensional electron gas for excess injection energies ranging from zero up
to the Fermi energy. We find that the detector signal consists of
quasiballistic electrons, which either have not undergone any electron-electron
collisions or have only been scattered at small angles. Theoretically, the
small-angle scattering exhibits distinct features that can be traced back to
the reduced dimensionality of the electron system. A number of nonlinear
effects, also related to the two-dimensional character of the system, are
discussed. In the simplest situation, the heating of the electron gas by the
high-energy part of the beam leads to a weakening of the signal of
quasiballistic electrons and to the appearance of thermovoltage. This results
in a nonmonotonic dependence of the detector signal on the intensity of the
injected beam, as observed experimentally.

</DOC>
<DOC>
<DOCNO> 9003 </DOCNO>
Positive Muon Knight Shift Measurements in U_{0.965}Th_{0.035}Be_{13}


  Muon spin rotation measurements of the temperature dependence of the Knight
shift in single crystals of U_{0.965}Th_{0.035}Be_{13} have been used to study
the static spin susceptibility below the transition temperatures T_{c1} and
T_{c2}. While an abrupt reduction of the susceptibility with decreasing
temperature is observed below T_{c1}, the susceptibility does not change below
T_{c2} and remains at a value below the normal-state susceptibility. In the
normal state we find an anomalous anisotropic temperature dependence of the
transferred hyperfine coupling between the muon spin and the U 5f-electrons.

</DOC>
<DOC>
<DOCNO> 170453 </DOCNO>
Engineering cavity-field states by projection synthesis


  We propose a reliable scheme for engineering a general cavity-field state.
This is different from recently presented strategies,where the cavity is
supposed to be initially empty and the field is built up photon by photon
through resonant atom-field interactions. Here, a coherent state is previously
injected into the cavity. So, the Wigner distribution function of the desired
state is constructed from that of the initially coherent state. Such an
engineering process is achieved through an adaptation of the recently proposed
technique of projection synthesis to cavity QED phenomena.

</DOC>
<DOC>
<DOCNO> 69541 </DOCNO>
Study of R-parity Violation at a mu-p Collider


  To explore the discovery possibilities of a high-energy muon-proton collider,
we examine signals that could arise from direct-channel formation of
supersymmetric-particle resonances through operators that do not respect
R-parity.

</DOC>
<DOC>
<DOCNO> 101994 </DOCNO>
Thirty-Six Unsolved Problems in Number Theory


  Partially or totally unsolved questions in number theory and geometry
especially, such as coloration problems, elementary geometric conjectures,
partitions, generalized periods of a number, length of a generalized period,
arithmetic and geometric progressions are exposed.

</DOC>
<DOC>
<DOCNO> 102852 </DOCNO>
Equivariant Cohomology and Representations of the Symmetric Group


  A cohomological study is made of an equivariant map betwen the configuration
space of n points in space and the flag manifold of U(n).

</DOC>
<DOC>
<DOCNO> 170032 </DOCNO>
Quantum correlations from local amplitudes and the resolution of the


  The Einstein-Podolsky-Rosen nonlocality puzzle has been recognized as one of
the most important unresolved issues in the foundational aspects of quantum
mechanics. We show that the problem is resolved if the quantum correlations are
calculated directly from local quantities which preserve the phase information
in the quantum system. We assume strict locality for the probability amplitudes
instead of local realism for the outcomes, and calculate an amplitude
correlation function.Then the experimentally observed correlation of outcomes
is calculated from the square of the amplitude correlation function. Locality
of amplitudes implies that the measurement on one particle does not collapse
the companion particle to a definite state. Apart from resolving the EPR
puzzle, this approach shows that the physical interpretation of apparently
`nonlocal' effects like quantum teleportation and entanglement swapping are
different from what is usually assumed. Bell type measurements do not change
distant states. Yet the correlations are correctly reproduced, when measured,
if complex probability amplitudes are treated as the basic local quantities. As
examples we discuss the quantum correlations of two-particle maximally
entangled states and the three-particle GHZ entangled state.

</DOC>
<DOC>
<DOCNO> 169970 </DOCNO>
Quantum Computation in Brain Microtubules? Decoherence and Biological


  The Penrose-Hameroff (`Orch OR') model of quantum computation in brain
microtubules has been criticized as regards the issue of environmental
decoherence. A recent report by Tegmark finds that microtubules can maintain
quantum coherence for only $10^{-13}$ s, far too short to be
neurophysiologically relevant. Here, we critically examine the assumptions
behind Tegmark's calculation and find that: 1) Tegmark's commentary is not
aimed at an existing model in the literature but rather at a hybrid that
replaces the superposed protein conformations of the `Orch OR' theory with a
soliton in superposition along the microtubule, 2) Tegmark predicts decreasing
decoherence times at lower temperature, in direct contradiction of the observed
behavior of quantum states, 3) recalculation after correcting Tegmark's
equation for differences between his model and the `Orch OR' model
(superposition separation, charge vs. dipole, dielectric constant) lengthens
the decoherence time to $10^{-5} - 10^{-4}$ s and invalidates a critical
assumption of Tegmark's derivation, 4) incoherent metabolic energy supplied to
the collective dynamics ordering water in the vicinity of microtubules at a
rate exceeding that of decoherence can counter decoherence effects (in the same
way that lasers avoid decoherence at room temperature), and 5) phases of actin
gelation may enhance the ordering of water around microtubule bundles, further
increasing the decoherence-free zone by an order of magnitude and the
decoherence time to $10^{-2} - 10^{-1}$ s. These revisions bring microtubule
decoherence into a regime in which quantum gravity can interact with
neurophysiology.

</DOC>
<DOC>
<DOCNO> 84713 </DOCNO>
Dynamics of spatially homogeneous locally rotationally symmetric


  The dynamics of the Einstein-Vlasov equations for a class of cosmological
models with four Killing vectors is discussed in the case of massive particles.
It is shown that in all models analysed the solutions with massive particles
are asymptotic to solutions with massless particles at early times. It is also
shown that in Bianchi types I and II the solutions with massive particles are
asymptotic to dust solutions at late times. That Bianchi type III models are
also asymptotic to dust solutions at late times is consistent with our results
but is not established by them.

</DOC>
<DOC>
<DOCNO> 174566 </DOCNO>
Strangeness in dense nuclear matter: A review of AGS results


  Enhancement in strangeness production and antihyperon to antibaryon ratio are
two important signatures of QGP formation. Both signatures have been measured
at the AGS. A review of these measurements is given. Implications of the
measurements are discussed.

</DOC>
<DOC>
<DOCNO> 120110 </DOCNO>
Internal shocks in the jets of blazars


  The development of instabilities leading to the formation of internal shocks
is expected in the relativistic outflows of both gamma-ray bursts and blazars.
The shocks heat the expanding ejecta, generate a tangled magnetic field and
accelerate leptons to relativistic energies. While this scenario has been
largely considered for the origin of the spectrum and the fast variability in
gamma-ray bursts, here we consider it in the contest of relativistic jets of
blazars. We calculate the expected spectra, light curves and time correlations
between emission at different wavelengths. The dynamical evolution of the wind
explains the minimum distance for dissipation (~10^{17} cm) to avoid
$\gamma$--$\gamma$ collisions and the low radiative efficiency required to
transport most of the kinetic energy to the extended radio structures. The
internal shock model allows to follow the evolution of changes, both dynamical
and radiative, along the entire jet, from the inner part, where the jet becomes
radiative and emits at high energies ($\gamma$-jet), to the parsec scale, where
the emission is mostly in the radio band (radio-jet). We have produced some
animations that can be found at http://www.merate.mi.astro.it/~lazzati/3C279/,
in which the temporal and spectral informations are shown together.

</DOC>
<DOC>
<DOCNO> 102772 </DOCNO>
Invitation to higher local fields, Part I, section 7: Parshin's higher


  This is a review of Parshin's higher local class field theory in
characteristic p.

</DOC>
<DOC>
<DOCNO> 11117 </DOCNO>
The three-dimensional, three-state Potts Model in an External Field


  We analyze the critical behaviour of the three-dimensional, three-state Potts
model in the presence of an external ordering field. From a finite size scaling
analysis on lattices of size up to 70**3 we determine the critical endpoint of
the line of first order phase transitions as (b_c, h_c) =(0.54938(2),
0.000775(10)). We determine the relevant temperature like and symmetry breaking
directions at this second order critical point and explicitly verify that it is
in the universality class of the three-dimensional Ising model.

</DOC>
<DOC>
<DOCNO> 68588 </DOCNO>
Alignment in hadronic interactions


  The alignment of the products of very high energy interactions seen in
mountain altitude experiments is one of the most puzzling phenomena in cosmic
ray physics for quite a long time. The observations of the Pamir and Chacaltaya
emulsion chamber groups and by the Tien-Shan extensive air shower experiment,
together with a very clear event seen in the Concorde French-Japanese
experiment in the stratosphere, makes the experimental basis very substantial.
In the present paper a novel possible explanation is put forward.

</DOC>
<DOC>
<DOCNO> 119441 </DOCNO>
High order symplectic integrators for perturbed Hamiltonian systems


  We present a class of symplectic integrators adapted for the integration of
perturbed Hamiltonian systems of the form $H=A+\epsilon B$. We give a
constructive proof that for all integer $p$, there exists an integrator with
positive steps with a remainder of order $O(\tau^p\epsilon +\tau^2\epsilon^2)$,
where $\tau$ is the stepsize of the integrator. The analytical expressions of
the leading terms of the remainders are given at all orders. In many cases, a
corrector step can be performed such that the remainder becomes
$O(\tau^p\epsilon +\tau^4\epsilon^2)$. The performances of these integrators
are compared for the simple pendulum and the planetary 3-Body problem of
Sun-Jupiter-Saturn.

</DOC>
<DOC>
<DOCNO> 117147 </DOCNO>
The Nuclear Force is Gravitation. Was Einstein Right?


  I combine the effects of Planck length, general relativity and Newtonian
gravity in one equation, to come up with a semi-classical model of gravity in
the form of deviation from Newtonian gravity. Einstein explained nuclear forces
in terms of gravity (Ref. 2). This reference is explicit in expressing
Einstein's attempts and describes them as misguided. My model shows Einstein
was not misguided in his attempts to explain nuclear forces in terms of
gravity. My model shows just the contrary. I use Planck length as what it is:
minimum distance that makes any sense. I make a subatomic distinction between
mass and space, a lesson learned from general relativity. General relativity is
about mass telling space how to curve and space telling mass how to move.
Unlike string theory, I use no imaginary dimensions. My model predicts maximum
nuclear force as the limit of gravitation and clearly yields Newtonian gravity
at a macroscopic scale in an unprecedented and consistent manner: Good-by to
quantum gravity.
  I am combining Newton, Planck and Einstein and to predict a limit of gravity
as Chandrashekhar did to predict his limit.

</DOC>
<DOC>
<DOCNO> 121264 </DOCNO>
The Razor's Edge: Magnetic Fields and Their Fundamental Role in Star


  We review theoretical models of the early stages of star formation, in which
gravitational collapse is strongly regulated by magnetic fields and the
associated process of ambipolar diffusion. We discuss results of numerical
simulations and analytical studies of core formation and collapse, which can be
directly tested against observation. We also focus on recent data which are
relevant to this theory of star formation, such as: observations of extended
infall in protostellar cores, estimates of evolutionary timescales ~ 1 Myr for
cores, measured mass-to-flux ratios of cores, and the relative alignment of
polarization vectors with apparent cloud elongation. It is shown that in all of
these areas, the data lie within the observationally allowable range of
parameter space. Other areas of interest (protostellar accretion rates and the
presence of core edges) and issues that remain unresolved or under study (the
role of non-thermal motions and cluster formation) are also discussed.
Moreover, we highlight some differences between our model predictions and those
of highly turbulent star formation models, and discuss how these differences
can be distinguished observationally.

</DOC>
<DOC>
<DOCNO> 99747 </DOCNO>
Einstein manifolds of non-negative sectional curvature and entropy


  We find obstructions to the existence of Einstein metrics of non-negative
sectional curvature on a smooth closed simply connected manifold of any
dimension. The results are achieved by combining the classical Morse theory of
the loop space with a new upper bound for the topological entropy of the
geodesic flow in terms of the curvature tensor.

</DOC>
<DOC>
<DOCNO> 102576 </DOCNO>
Generating All Wigner Functions


  In the context of phase-space quantization, matrix elements and observables
result from integration of c-number functions over phase space, with Wigner
functions serving as the quasi-probability measure. The complete sets of Wigner
functions necessary to expand all phase-space functions include off-diagonal
Wigner functions, which may appear technically involved. Nevertheless, it is
shown here that suitable generating functions of these complete sets can often
be constructed, which are relatively simple, and lead to compact evaluations of
matrix elements. New features of such generating functions are detailed and
explored for integer-indexed sets, such as for the harmonic oscillator, as well
as continuously indexed ones, such as for the linear potential and the
Liouville potential. The utility of such generating functions is illustrated in
the computation of star functions, spectra, and perturbation theory in phase
space.

</DOC>
<DOC>
<DOCNO> 10645 </DOCNO>
An algebraic approach to coarse graining


  We propose that Kreimer's method of Feynman diagram renormalization via a
Hopf algebra of rooted trees can be fruitfully employed in the analysis of
block spin renormalization or coarse graining of inhomogeneous statistical
systems. Examples of such systems include spin foam formulations of
non-perturbative quantum gravity as well as lattice gauge and spin systems on
irregular lattices and/or with spatially varying couplings. We study three
examples which are Z_2 lattice gauge theory on irregular 2-dimensional
lattices, Ising/Potts models with varying bond strengths and (1+1)-dimensional
spin foam models.

</DOC>
<DOC>
<DOCNO> 69927 </DOCNO>
On power corrections to the event shape distributions in QCD


  We study power corrections to the differential thrust, heavy jet mass and
C-parameter distributions in the two-jet kinematical region in e^+e^-
annihilation. We argue that away from the end-point region, e>>
\Lambda_{QCD}/Q, the leading 1/Q-power corrections are parameterized by a
single nonperturbative scale while for e \Lambda_{QCD}/Q one encounters a novel
regime in which power corrections of the form 1/(Qe)^n have to be taken into
account for arbitrary n. These nonperturbative corrections can be resummed and
factor out into a universal nonperturbative distribution, the shape function,
and the differential event shape distributions are given by convolution of the
shape function with perturbative cross-sections. Choosing a simple ansatz for
the shape function we demonstrate a good agreement of the obtained QCD
predictions for the distributions and their lowest moments with the existing
data over a wide energy interval.

</DOC>
<DOC>
<DOCNO> 13476 </DOCNO>
Stochastic Dynamics of a Vortex Loop. Thermal Equilibrium


  We study stochastic behavior of a single vortex loop appeared in imperfect
Bose gas. Dynamics of Bose-condensate is supposed to obey Gross-Pitaevskii
equation with additional noise satisfying fluctuation-dissipation relation. The
corresponding Fokker-Planck equation for probability functional has a solution
$\mathcal{P}(\{{\psi}(\mathbf{r})\})=\mathcal{N}\exp (-H{\psi}(\mathbf{r)}
/T),$ where $H\psi(\mathbf{r})$ is a Ginzburg-Landau free energy. Considering a
vortex filaments as a topological defects of the field ${\psi}(\mathbf{r})$ we
derive a Langevin-type equation of motion of the line with correspondingly
transformed stirring force. The respective Fokker-Planck equation for
probability functional $\mathcal{P}(\{\mathbf{s}(\xi)\})$ in vortex loop
configuration space is shown to have a solution of the form
$\mathcal{P}(\{\mathbf{s}(\xi)\})=\mathcal{N}\exp (-H{\mathbf{s}} /T),$ where
$\mathcal{N}$ is a normalizing factor and $H{\mathbf{s}}$ is energy of vortex
line configurations. In other words a thermal equilibrium of Bose-condensate
results in a thermal equilibrium of vortex loops appeared in Bose-condensate.
Some consequences of that fact and possible violations are discussed.

</DOC>
<DOC>
<DOCNO> 10951 </DOCNO>
Gauge Invariant Formulations of Dicke-Preparata Super-Radiant Models


  In a gauge invariant formulation of the molecular electric dipole-photon
interaction, the rigorous coupling is strictly linear in the photon creation
and photon annihilation operators. The linear coupling allows for a
super-radiant phase transition as in the Hepp-Lieb formulation. A previous
notion of a quadratic-coupling ``no-go theorem'' for super-radiance is
incorrect. Also incorrect is a previous assertion that the dipole-photon
coupling has absolutely no effect on the thermal equations of state. These
dubious assertions were based on incorrect canonical transformations which
eliminated the electric field (and thereby eliminated the dipole-photon
interaction) which is neither mathematically nor physically consistent. The
correct form of the canonical transformations are given in this work which
allows for the physical reality of super-radiant condensed matter phases.

</DOC>
<DOC>
<DOCNO> 99976 </DOCNO>
Log Canonical Thresholds and Generalized Eckardt Points


  Let $X$ be a smooth hypersurface of degree $n\geq 3$ in $\mathbb{P}^n$. We
prove that the log canonical threshold of $H\in|-K_X|$ is at least
$\frac{n-1}{n}$. Under the assumption of the Log minimal model program, we also
prove that a hyperplane section $H$ of $X$ is a cone in $\mathbb{P}^{n-1}$ over
a smooth hypersurface of degree $n$ in $\mathbb{P}^{n-2}$ if and only if the
log canonical threshold of $H$ is $\frac{n-1}{n}$.

</DOC>
<DOC>
<DOCNO> 12451 </DOCNO>
Structural response to local charge order in underdoped but


  We report an anomalous local structural response in the CuO2 planes
associated with the appearance of charge inhomogeneities at low temperature in
underdoped but superconducting La2-x(Sr,Ba)xCuO4. We used pair distribution
function analysis of neutron powder diffraction data. The increase in the Cu-O
bond length distribution at low temperature has an onset temperature which
correlates with observations of charge and spin freezing seen by other probes.

</DOC>
<DOC>
<DOCNO> 84749 </DOCNO>
Gravitation Wave Emission from Radio Pulsars Revisited


  We report a new pulsar population synthesis based on Monte Carlo techniques,
aiming to estimate the contribution of galactic radio pulsars to the continuous
gravitational wave emission. Assuming that the rotation periods of pulsars at
birth have a Gaussian distribution, we find that the average initial period is
290 ms. The number of objects with periods equal to or less than 0.4 s, and
therefore capable of being detected by an interferometric gravitational antenna
like VIRGO, is of the order of 5100-7800. With integration times lasting
between 2 and 3 yr, our simulations suggest that about two detections should be
possible, if the mean equatorial ellipticity of the pulsars is $\epsilon$
=10$^{-6}$. A mean ellipticity an order of magnitude higher increases the
expected number of detections to 12-18, whereas for $\epsilon < 10^{-6}$, no
detections are expected

</DOC>
<DOC>
<DOCNO> 121141 </DOCNO>
omega Centauri - a former nucleus of a dissolved dwarf galaxy? New


  CCD vby Stroemgren photometry of a statistically complete sample of red
giants and stars in the main sequence turn-off region in omega Centauri has
been used to analyse the apparently complex star formation history of this
cluster. From the location of stars in the (b-y),m_1 diagram metallicities have
been determined. These have been used to estimate ages of different
sub-populations in the color-magnitude diagram. The metal-poor population
around -1.7 dex is the oldest population found. More metal-rich stars between
[Fe/H]=-1.5 and -1.0 dex tend to be 1-3 Gyr younger. These stars are more
concentrated towards the center than the metal-poor ones. The most-metal rich
stars (-0.7 dex) might be up to 6 Gyr younger than the oldest population. They
are asymmetrically distributed around the center with an excess of stars
towards the South. We argue that the Stroemgren metallicity in terms of element
abundances has another meaning than in other globular clusters. From a
comparison with spectroscopic element abundances, we find the best correlation
with the sum C+N. The high Stroemgren metallicities, if interpreted by strong
CN-bands, result from progressively higher N and perhaps C abundances in
comparison to iron. We see an enrichment already among the metal-poor
population, which is difficult to explain by self-enrichment alone. An
attractive speculation is that omega Cen was the nucleus of a dwarf galaxy. We
propose a scenario in which omega Cen experienced mass inflow over a long
period of time, until the gas content of its host galaxy was so low that star
formation in omega Cen stopped, or alternatively the gas was stripped off
during its infall in the Milky Way potential. A mass inflow occuringcn a clumpy
and discontinuous manner could explain several of our findings.

</DOC>
<DOC>
<DOCNO> 121871 </DOCNO>
The Upsilon Andromedae System: Models and Stability


  Radial velocity observations of the F8 V star Upsilon Andromedae taken at
Lick and at Whipple Observatories have revealed evidence of three periodicities
in the line-of-sight velocity of the star. These periodicities have been
interpreted as evidence for at least three low mass companions (LMCs) revolving
around Upsilon Andromedae. The mass and orbital parameters inferred for these
companions raise questions about the dynamical stability of the system. We
report here results from our independent analysis of the published radial
velocity data as well as new unpublished data taken at Lick Observatory. Our
results confirm the finding of three periods in the data. Our best fits to the
data, on the assumption that these periods arise from the gravitational
perturbations of companions in keplerian orbits, is also generally in
agreement, but with some differences, from the earlier findings. We find that
the available data do not constrain well the orbital eccentricity of the middle
companion in a three-companion model of the data. We also find that in order
for our best-fit model to the Lick data to be dynamically stable over the
lifetime of the star (~2 billion years), the system must have a mean
inclination to the plane of the sky greater than 13 degrees. The corresponding
minimum inclination for the best fit to the Whipple data set is 19 degrees.
These values imply that the maximum mass for the outer companion can be no
greater than about 20 Jupiter masses. Our analysis of the stability of the
putative systems also places constraints on the relative inclinations of the
orbital planes of the companions. We comment on global versus local (i.e.,
method of steepest descent) means of finding best-fit orbits from radial
velocity data sets.

</DOC>
<DOC>
<DOCNO> 151337 </DOCNO>
Gravitational Couplings for y-Gop-Planes


  The Wess-Zumino action for y deformed and generalized orientifold planes
(yGOp-planes) is presented and one power expantion is realized from which
processes that involves yGOp-planes, RR-forms, gravitons and gaugeons, are
obtained. Finally non-standard yGOp-planes are showed.

</DOC>
<DOC>
<DOCNO> 170649 </DOCNO>
Quantum Chaos and the Black Body Radiation


  We discuss a mechanical model which mimics the main features of the radiation
matter interaction in the black body problem. The pure classical dynamical
evolution, with a simple discretization of the action variables, leads to the
Stefan- Boltzmann law and to the Planck distribution without any additional
statistical assumption.

</DOC>
<DOC>
<DOCNO> 40111 </DOCNO>
Search for Decays of B^{0} Mesons into Pairs of Leptons: B{0} ->


  We search for the decays of the $B^0$ meson into $e^+e^-$, $\mu^+\mu^-$
$e^{\pm}\mu^{\mp}$ pairs in a sample of $9.7\times 10^6$ $B{\bar B}$ pairs
recorded by CLEO detector. No signal is found, and the following upper limits
on the corresponding branching fractions are established: $<8.3\times 10^{-7}$,
$<6.1\times 10^{-7}$, $< 15\times 10^{-7}$ at 90% confidence level. A new lower
limit on the Pati-Salam leptoquark mass $M_{LQ}>27$ TeV is established at 90%
confidence level.

</DOC>
<DOC>
<DOCNO> 122679 </DOCNO>
Radio Variability of Sagittarius A* - A 106 Day Cycle


  We report the presence of a 106-day cycle in the radio variability of Sgr A*
based on an analysis of data observed with the Very Large Array (VLA) over the
past 20 years. The pulsed signal is most clearly seen at 1.3 cm with a ratio of
cycle frequency to frequency width f/Delta_f= 2.2+/-0.3. The periodic signal is
also clearly observed at 2 cm. At 3.6 cm the detection of a periodic signal is
marginal. No significant periodicity is detected at both 6 and 20 cm. Since the
sampling function is irregular we performed a number of tests to insure that
the observed periodicity is not the result of noise. Similar results were found
for a maximum entropy method and periodogram with CLEAN method. The probability
of false detection for several different noise distributions is less than 5%
based on Monte Carlo tests. The radio properties of the pulsed component at 1.3
cm are spectral index alpha ~ 1.0+/- 0.1 (for S nu^alpha), amplitude Delta
S=0.42 +/- 0.04 Jy and characteristic time scale Delta t_FWHM ~ 25 +/- 5 days.
The lack of VLBI detection of a secondary component suggests that the
variability occurs within Sgr A* on a scale of ~5 AU, suggesting an instability
of the accretion disk.

</DOC>
<DOC>
<DOCNO> 11296 </DOCNO>
Comment on "Microwave vortex dissipation of superconducting Nd-Ce-Cu-O


  While the electrodynamic treatment of a superconducting thin film by Yeh et
al. [Phys. Rev. B 48, 9861 (1993)] ostensibly has application for the
"thin-film limit," their work is shown to employ bulk-like instead of thin-film
electrodynamics, and as such obtains an ostensible violation of the first law
of thermodynamics and a surface resistance independent of the resistivity.
Other theoretical and experimental difficulties are briefly noted.

</DOC>
<DOC>
<DOCNO> 100979 </DOCNO>
Topological gravity in genus 2 with two primary fields


  We calculate the genus 2 correlation functions of two-dimensional topological
gravity, in a background with two primary fields, using the genus 2 topological
recursion relations.

</DOC>
<DOC>
<DOCNO> 8529 </DOCNO>
Anomalous scaling dimensions and stable charged fixed-point of type-II


  The critical properties of a type-II superconductor model are investigated
using a dual vortex representation. Computing the propagators of gauge field
$\vec{A}$ and dual gauge field $\vec{h}$ in terms of a vortex correlation
function, we obtain the values $\eta_A=1$ and $\eta_h=1$ for their anomalous
dimensions. This provides support for a dual description of the Ginzburg-Landau
theory of type-II superconductors in the continuum limit, as well as for the
existence of a stable charged fixed point of the theory, not in the 3DXY
universality class.

</DOC>
<DOC>
<DOCNO> 12915 </DOCNO>
Unpaired Majorana fermions in quantum wires


  Certain one-dimensional Fermi systems have an energy gap in the bulk spectrum
while boundary states are described by one Majorana operator per boundary
point. A finite system of length $L$ possesses two ground states with an energy
difference proportional to $\exp(-L/l_0)$ and different fermionic parities.
Such systems can be used as qubits since they are intrinsically immune to
decoherence. The property of a system to have boundary Majorana fermions is
expressed as a condition on the bulk electron spectrum. The condition is
satisfied in the presence of an arbitrary small energy gap induced by proximity
of a 3-dimensional p-wave superconductor, provided that the normal spectrum has
an odd number of Fermi points in each half of the Brillouin zone (each spin
component counts separately).

</DOC>
<DOC>
<DOCNO> 8140 </DOCNO>
Single hole dynamics in the t-J model on a square lattice


  We present quantum Monte Carlo (QMC) simulations for a single hole in a t-J
model from J=0.4t to J=4t on square lattices with up to 24 x 24 sites. The
lower edge of the spectrum is directly extracted from the imaginary time
Green's function. In agreement with earlier calculations, we find flat bands
around $(0,\pm\pi)$, $(\pm\pi,0)$ and the minimum of the dispersion at
$(\pm\pi/2,\pm\pi/2)$. For small J both self-consistent Born approximation and
series expansions give a bandwidth for the lower edge of the spectrum in
agreement with the simulations, whereas for J/t > 1, only series expansions
agree quantitatively with our QMC results. This band corresponds to a coherent
quasiparticle. This is shown by a finite size scaling of the quasiparticle
weight $Z(\vec k)$ that leads to a finite result in the thermodynamic limit for
the considered values of $J/t$. The spectral function $A(\vec k, \omega)$ is
obtained from the imaginary time Green's function via the maximum entropy
method. Resonances above the lowest edge of the spectrum are identified, whose
J-dependence is quantitatively described by string excitations up to J/t=2.

</DOC>
<DOC>
<DOCNO> 152607 </DOCNO>
On schizosymmetric superfields and sl(2/1,C)_R supersymmetry


  Superfield expansions over four-dimensional graded spacetime
$(x^\mu,\theta^\nu)$, with Minkowski coordinates $x$ extended by vector
Grassmann variables $\theta$, are investigated. By appropriate identification
of the physical Lorentz algebra in the even and odd parts of the superfield, a
typology of `schizofields' containing both integer and half-integer spin fields
is established. For two of these types, identified as `gauge potential'-like
and `field strength'-like schizofields, an $sl(2/1,{\mathbb C})_{\mathbb R}$
supersymmetry at the component field level is demonstrated. Prospects for a
schizofield calculus, and application of these types of fields to the particle
spectrum, are adumbrated.

</DOC>
<DOC>
<DOCNO> 121617 </DOCNO>
Number Count of Peaks in the CMB Map


  We investigate the dependence of cosmological parameters on the number count
of peaks (local maxima and minima) in the cosmic microwave background (CMB)
sky. The peak statistics contains the whole information of acoustic
oscillations in the angular power spectrum $C_l$ over $l$-space and thus it can
place complementary constraints on the cosmological parameters to those
obtained from measurements of $C_l$. Based on the instrumental specifications
of Planck, we find that the number count of peaks can provide new constraints
on the combination of the matter density $\Omega_{\rm m}$ and the Hubble
parameter $h$ approximately scaled as $\Omega_{\rm m} h^{-4.9}$ for a flat
$\Lambda$CDM model with $\Omega_{m}=0.3$ and $h=0.7$. Therefore, we suggest
that combining it with the constraints from $C_l$ scaled as $\Omega_{m}h^{3.8}$
(or commonly $\Omega_{\rm m}h^2$) can potentially determine $\Omega_{\rm m}$ or
equivalently solve the cosmic degeneracy by the CMB data alone.

</DOC>
<DOC>
<DOCNO> 70269 </DOCNO>
Possible Implications of Small or Large CP Violation in B^0_d vs


  We argue that a small or large CP-violating asymmetry {\cal A}_{\psi K_S} in
B^0_d vs \bar{B}^0_d --> J/\psi K_S decays, which seems to be favored by the
recent BaBar or Belle data, might hint at the existence of new physics in B^0_d
- \bar{B}^0_d mixing. We present a model-independent framework to show how new
physics in B^0_d - \bar{B}^0_d mixing modifies the standard-model CP-violating
asymmetry {\cal A}^{\rm SM}_{\psi K_S}. We particularly emphasize that an
experimental confirmation of {\cal A}_{\psi K_S} \approx {\cal A}^{\rm
SM}_{\psi K_S} must not imply the absence of new physics in B^0_d - \bar{B}^0_d
mixing.

</DOC>
<DOC>
<DOCNO> 152452 </DOCNO>
Supersymmetric Field Theories on Deformed Space-Time


  Field theories on "quantum" or deformed space-time are considered here. The
Moyal-Weyl deformation breaks the Lorentz invariance of the theory, but one can
still require invariance under the supertranslation algebra. We investigate
some aspects of the Wess-Zumino model, super Yang-Mills theories and analyze
the correspondence of the later with the supersymmetric Born-Infeld action.

</DOC>
<DOC>
<DOCNO> 116703 </DOCNO>
Quantum energy flow in atomic ions moving in magnetic fields


  Using a combination of semiclassical and recently developed wave packet
propagation techniques we find the quantum self-ionization process of highly
excited ions moving in magnetic fields which has its origin in the energy
transfer from the center of mass to the electronic motion. It obeys a time
scale by orders of magnitude larger than the corresponding classical process.
Importantly a quantum coherence phenomenon leading to the intermittent
behaviour of the ionization signal is found and analyzed. Universal properties
of the ionization process are established.

</DOC>
<DOC>
<DOCNO> 117320 </DOCNO>
Differential and partial cross sections of elastic and inelastic


  Scattering of positronium (Ps) by helium atom has been investigated in a
three-Ps-state coupled-channel model including Ps(1s,2s,2p) states using a
recently proposed time-reversal-symmetric regularized electron-exchange model
potential. Specifically, we report results of differential cross sections for
elastic scattering and target-elastic Ps excitations. We also present results
for total and different partial cross sections and compare them with experiment
and other calculations.

</DOC>
<DOC>
<DOCNO> 8193 </DOCNO>
The viscous slowing down of supercooled liquids as a


  We propose that the salient feature to be explained about the glass
transition of supercooled liquids is the temperature-controlled superArrhenius
activated nature of the viscous slowing down, more strikingly seen in
weakly-bonded, fragile systems. In the light of this observation, the relevance
of simple models of spherically interacting particles and that of models based
on free-volume congested dynamics are questioned. Finally, we discuss how the
main aspects of the phenomenology of supercooled liquids, including the
crossover from Arrhenius to superArrhenius activated behavior and the
heterogeneous character of the $\alpha$ relaxation, can be described by an
approach based on frustration-limited domains.

</DOC>
<DOC>
<DOCNO> 10784 </DOCNO>
Role of Bose enhancement in photoassociation


  We discuss the role of Bose enhancement of the dipole matrix element in
photoassociation, using stimulated Raman adiabatic passage as an example. In a
nondegenerate gas the time scale for coherent optical transients tends to
infinity in the thermodynamic limit, whereas Bose enhancement keeps this time
scale finite in a condensate. Coherent transients are therefore absent in
photoassociation of a thermal nondegenerate gas, but are feasible if the gas is
a condensate.

</DOC>
<DOC>
<DOCNO> 7675 </DOCNO>
Transforming Gaussian diffusion into fractional a generalized law of


  The fractional Fokker-Planck equation (FFPE) [R. Metzler, E. Barkai, J.
Klafter, Phys. Rev. Lett., 82, 3563 (1999)] describes an anomalous sub
diffusive behavior of a particle in an external force field. In this paper we
present the solution of the FFPE in terms of an integral transformation. The
transformation maps the solution of ordinary Fokker-Planck equation onto the
solution of the FFPE. We investigate in detail the force free particle and the
particle in uniform and harmonic fields. The meaning of the transformation is
explained based on the asymptotic solution of the continuous time random walk
(CTRW). We also find an exact solution of the CTRW and compare the CTRW result
with the integral solution of the FFPE for the force free case.

</DOC>
<DOC>
<DOCNO> 119463 </DOCNO>
Lyman-alpha Forest Constraints on the Mass of Warm Dark Matter and the


  High resolution N-body simulations of cold dark matter (CDM) models predict
that galaxies and clusters have cuspy halos with excessive substructure.
Observations reveal smooth halos with central density cores. One possible
resolution of this conflict is that the dark matter is warm (WDM); this will
suppress the power spectrum on small scales. The Lyman-alpha forest is a
powerful probe of the linear power spectrum on these scales. We use
collisionless N-body simulations to follow the evolution of structure in WDM
models, and analyze artificial Lyman-alpha forest spectra extracted from them.
By requiring that there is enough small-scale power in the linear power
spectrum to reproduce the observed properties of the Lyman-alpha forest in
quasar spectra, we derive a lower limit to the mass of the WDM particle of 750
eV. This limit is robust to reasonable uncertainties in our assumption about
the temperature of the mean density gas (T0) at z=3. We argue that any model
that suppresses the CDM linear theory power spectrum more severely than a 750
eV WDM particle cannot produce the Lyman-alpha forest.

</DOC>
<DOC>
<DOCNO> 119987 </DOCNO>
3-D MHD Numerical Simulations of Cloud-Wind Interactions


  We present results from three-dimensional (3-D) numerical simulations
investigating the magnetohydrodynamics of cloud-wind interactions. The initial
cloud is spherical while the magnetic field is uniform and transverse to the
cloud motion. A simplified analytical model that describes the magnetic energy
evolution in front of the cloud is developed and compared with simulation
results. In addition, it is found the interaction of the cloud with a
magnetized interstellar medium (ISM) results in the formation of a highly
structured magnetotail. The magnetic flux in the wake of the cloud organizes
into flux ropes and a reconnection, current sheet is developed, as field lines
of opposite polarity are brought close together near the symmetry axis. At the
same time, magnetic pressure is strongly enhanced at the leading edge of the
cloud from the stretching of the field lines that occurs there. This has an
important dynamical effect on the subsequent evolution of the cloud, since some
unstable modes tend to be strongly enhanced.

</DOC>
<DOC>
<DOCNO> 100426 </DOCNO>
The q-twisted cohomology and the q-hypergeometric function at |q|=1


  We construct the q-twisted cohomology associated with the q-multiplicative
function of Jordan-Pochhammer type at |q|=1. In this framework, we prove the
Heine's relations and a connection formula for the q-hypergeometric function of
the Barnes type. We also prove an orthogonality relation of the q-little Jacobi
polynomials at |q|=1.

</DOC>
<DOC>
<DOCNO> 39784 </DOCNO>
Inclusive Sigma+ and Sigma0 Production in Hadronic Z Decays


  We report on measurements of the inclusive production rate of Sigma+ and
Sigma0 baryons in hadronic Z decays collected with the L3 detector at LEP. The
Sigma+ baryons are detected through the decay Sigma+ -> p pi0, while the Sigma0
baryons are detected via the decay mode Sigma0 -> Lambda gamma. The average
numbers of Sigma+ and Sigma0 per hadronic Z decay are measured to be: <
N_Sigma+ > + < N_Sigma+~ > = 0.114 +/- 0.011 (stat) +/- 0.009 (syst), <
N_Sigma0 > + < N_Sigma0~ > = 0.095 +/- 0.015 (stat) +/- 0.013 (syst). These
rates are found to be higher than the predictions from Monte Carlo
hadronization models and analytical parameterizations of strange baryon
production.

</DOC>
<DOC>
<DOCNO> 117013 </DOCNO>
The easiest way to Heaviside ellipsoid


  The formula for the electric field of a point charge moving with constant
velocity is derived using the symmetry properties of Maxwell's equations - its
Lorentz invariance. In contrast to conventional treatments, the derivation
presented does not use retarded integrals or relativity transformations.

</DOC>
<DOC>
<DOCNO> 8523 </DOCNO>
Transition Temperature and Magnetoresistance in Double-Exchange


  We develop a variational mean-field theory of the ferromagnetic transition in
compounds like Lanthanum-Manganite within the framework of the Double-Exchange
Model supplemented by modest disorder. We obtain analytical expressions for the
transition temperature, its variation with the valence electron-density and its
decrease with disorder.
 We derive an expression for the conductivity for both the paramagnetic and the
ferromangetic metallic phases, and study its dependence on the temperature and
magnetic field. A simple relation between the resistivity in the ferromagnetic
phase and the spontaneous magnetization is found. Our results are in a good
agreement with the experimental data on transition temperatures and resistivity
in the manganite compounds with relatively small disorder. We comment on the
effects of increased disorder.

</DOC>
<DOC>
<DOCNO> 101004 </DOCNO>
Pretty Good Gravity


  A theory of topological gravity is a homotopy-theoretic representation of the
Segal-Tillmann topologification of a two-category with cobordisms as morphisms.
This note describes a relatively accessible example of such a thing, suggested
by the wall-crossing formulas of Donaldson theory.

</DOC>
<DOC>
<DOCNO> 117036 </DOCNO>
Equation of state of fully ionized electron-ion plasmas. II. Extension


  The analytic equation of state of nonideal Coulomb plasmas consisting of
pointlike ions immersed in a polarizable electron background (physics/9807042)
is improved, and its applicability range is considerably extended. First, the
fit of the electron screening contribution in the free energy of the Coulomb
liquid is refined at high densities where the electrons are relativistic.
Second, we calculate the screening contribution for the Coulomb solid (bcc and
fcc) and derive an analytic fitting expression. Third, we propose a simple
approximation to the internal and free energy of the liquid one-component
plasma of ions, accurate within the numerical errors of the most recent Monte
Carlo simulations. We obtain an updated value of the coupling parameter at the
solid-liquid phase transition for the one-component plasma: Gamma_m = 175.0
(+/- 0.4).

</DOC>
<DOC>
<DOCNO> 70259 </DOCNO>
Remarks on the Calculation of the Enhancement Factor in the K -> 2 pion


  The problem of calculation of the enhancement factor due to the strong pion
final state interaction is reexamined in the light of recent interest in
understanding of the origine of the $\Delta I=1/2$ rule and calculations of the
CP violation parameter $\epsilon^{\prime}/\epsilon$. It is shown that the
traditional method of calculating the \emph{absolute} enhancement factor is
model dependent, while the method of relating $K \to 2\pi$ amplitude to the
$K-\pi$ matrix element using Current Algebra is on a safer ground.

</DOC>
<DOC>
<DOCNO> 8948 </DOCNO>
Equilibrating Glassy Systems with Parallel Tempering


  We discuss the efficiency of the so-called parallel tempering method to
equilibrate glassy systems also at low temperatures. The main focus is on two
structural glass models, SiO_2 and a Lennard-Jones system, but we also
investigate a fully connected 10 state Potts-glass. By calculating the mean
squared displacement of a tagged particle and the spin-autocorrelation
function, we find that for these three glass-formers the parallel tempering
method is indeed able to generate, at low temperatures, new independent
configurations at a rate which is O(100) times faster than more traditional
algorithms, such as molecular dynamics and single spin flip Monte Carlo
dynamics. In addition we find that this speedup increases with decreasing
temperature. The reliability of the results is checked by calculating the
distribution of the energy at various temperatures and by showing that these
can be mapped onto each other by the reweighting technique.

</DOC>
<DOC>
<DOCNO> 118756 </DOCNO>
Lyman alpha Absorption Systems and the Intergalactic Medium


  The last few years have seen a dramatic improvement in our understanding of
the origin of Lyman alpha absorption systems. Hydrodynamic numerical
simulations of cold dark matter dominated universes have shown that the many
properties of the Lyman alpha absorption systems can be explained by a
photoionized, space-filling, intergalactic medium. Lyman alpha lines offer
promising probes of the photoionizing background, the amplitude of the mass
fluctuations at high redshift and the evolution of the equation of state of the
intergalactic medium.

</DOC>
<DOC>
<DOCNO> 7915 </DOCNO>
Bound states in the three dimensional phi^4 model


  We discuss the spectrum of the three dimensional phi^4 theory in the broken
symmetry phase. In this phase the effective potential between the elementary
quanta of the model is attractive and bound states of two or more of them may
exist. We give theoretical and numerical evidence for the existence of these
bound states. Looking in particular at the Ising model realization of the phi^4
theory we show, by using duality, that these bound states are in one-to-one
correspondence with the glueball states of the gauge Ising model. We discuss
some interesting consequences of this identification.

</DOC>
<DOC>
<DOCNO> 72091 </DOCNO>
Supernova Neutrino Oscillations


  We discuss some possible influence of neutrino oscillations on physics of
supernova mainly focusing on the observations of $\bar{\nu}_e$, and present
some analysis of SN1987A data in the light of three neutrino mixing scheme.

</DOC>
<DOC>
<DOCNO> 151565 </DOCNO>
D-Brane Primer


  Following is a collection of lecture notes on D-branes, which may be used by
the reader as preparation for applications to modern research applications such
as: the AdS/CFT and other gauge theory/geometry correspondences, Matrix Theory
and stringy non-commutative geometry, etc. In attempting to be reasonably
self-contained, the notes start from classical point-particles and develop the
subject logically (but selectively) through classical strings, quantisation,
D-branes, supergravity, superstrings, string duality, including many detailed
applications. Selected focus topics feature D-branes as probes of both
spacetime and gauge geometry, highlighting the role of world-volume curvature
and gauge couplings, with some non-Abelian cases. Other advanced topics which
are discussed are the (presently) novel tools of research such as fractional
branes, the enhancon mechanism, D(ielectric)-branes and the emergence of the
fuzzy/non-commutative sphere.

</DOC>
<DOC>
<DOCNO> 13891 </DOCNO>
Vibrational entropy, configurational entropy, and the fragility of


  A thermodynamic measure of the fragility of liquids has recently (Ito et al
ref.1) been defined in terms of the temperature dependence of the excess
entropy of liquid over crystal, scaled by the excess entropy at the glass
transition temperature, and it has been correlated with kinetic fragility. The
correlation has been vigorously contested [2] using dielectric relaxation data
on some molecular liquids. We put this conflict in perspective using an
extensive data set covering all classes of liquids while retaining the cases of
ref 2. The excess entropy of the liquid, used in the thermodynamic quantity
being correlated, has both configurational and vibrational components. This is
the source of a second conflict which concerns the relative importance of these
two components. Experimental tests supporting the Adam-Gibbs "entropy" theory
of the temperature dependence of transport in viscous liquids have mostly been
made using the excess entropy, but recent simulation studies on the hard sphere
fluid [3] SPC-E water [4] and mixed LJ [5,6] have shown, as in the A-G theory,
a correlation with the configurational component. We show why, in laboratory
studies, the correlation should be with both, inextricably. In the course of
this demonstration we identify a key role for excess vibrational entropy in
causing fragile behavior in ambient pressure liquids.

</DOC>
<DOC>
<DOCNO> 70189 </DOCNO>
QCD factorization for $B\to\pi K$ decays


  We examine some consequences of the QCD factorization approach to
non-leptonic B decays into $\pi K$ and $\pi \pi$ final states, including a set
of enhanced power corrections. Among the robust predictions of the approach we
find small strong-interaction phases (with one notable exception) and a pattern
of CP-averaged branching fractions, which in some cases differ significantly
from the current central values reported by the CLEO Collaboration.

</DOC>
<DOC>
<DOCNO> 69649 </DOCNO>
Dear Santa: Heavy Flavour Physics at Neutrino Factories - Desires from


  Even in 2010 the CKM parameters $V_{cs}$, $V_{cd}$ and $V_{ub}$ will be known
with less than desirable accuracy; the discovery potential for New Physics in
charm decays -- in particular their CP asymmetries -- will be far from
exhausted; important tests of our theoretical tools will not have been
performed. I sketch the impact a $\nu$fact could have in these areas.

</DOC>
<DOC>
<DOCNO> 99656 </DOCNO>
The Standard Model - the Commutative Case: Spinors, Dirac Operator and


  The present paper is a short survey on the mathematical basics of Classical
Field Theory including the Serre-Swan' theorem, Clifford algebra bundles and
spinor bundles over smooth Riemannian manifolds, Spin^C-structures, Dirac
operators, exterior algebra bundles and Connes' differential algebras in the
commutative case, among other elements. We avoid the introduction of principal
bundles and put the emphasis on a module-based approach using Serre-Swan's
theorem, Hermitian structures and module frames. A new proof (due to Harald
Upmeier) of the differential algebra isomorphism between the set of smooth
sections of the exterior algebra bundle and Connes' differential algebra is
presented.

</DOC>
<DOC>
<DOCNO> 9592 </DOCNO>
Enthalpy recovery in semicrystalline polymers


  Constitutive equations are derived for enthalpy recovery in polymeric glasses
after thermal jumps. The model is based on the theory of cooperative relaxation
in a version of the trapping concept. It is demonstrated that some critical
temperature and some critical degree of crystallinity exist above which the
energy landscape becomes homogeneous and structural relaxation ceases.

</DOC>
<DOC>
<DOCNO> 14134 </DOCNO>
Molecular dynamics simulation of the fragile glass former


  We present a molecular dynamics study of the collective dynamics of a
flexible model for the fragile glass-former orthoterphenyl [ S. Mossa, R. Di
leonardo, G. Ruocco, and M. Sampoli, Phys. Rev. E 62, 612 (2000)]. We study the
behavior of the coherent scattering functions, considering the density
fluctuations of both molecular and phenyl rings centers of mass; moreover we
directly simulate the neutron scattering spectra taking into account both the
contributions due to the carbon and hydrogens atoms. We compare our results
with the main predictions of the Mode Coupling Theory and with the available
coherent neutron scattering experimental data.

</DOC>
<DOC>
<DOCNO> 85523 </DOCNO>
Distorted charged dilaton black holes


  We construct exact static, axisymmetric solutions of Einstein-Maxwell-dilaton
gravity presenting distorted charged dilaton black holes. The thermodynamics of
such distorted black holes is also discussed.

</DOC>
<DOC>
<DOCNO> 152454 </DOCNO>
New results for the quantum supersymmetric kink


  We review our work on computations of the quantum corrections to the mass and
the central charge of the susy kink. For the mass corrections, we find that the
widely used momentum cut-off scheme gives an incorrect result, but we deduce
through smoothing of the cut-off an extra term in the mass formula, which
produces the correct result. We discover the importance of boundary effects for
the mode number cut-off regularization scheme. We introduce the notion of
delocalized boundary energy. We discuss two discrete $Z_2$ symmetries and their
importance to the mode number approach. For the central charge corrections, we
use momentum cut-off regularization with two cut-offs, one for propagators and
another for Dirac delta functions. We then compute the quantum anomaly in the
central charge, and find that it restores the BPS bound at the one-loop level
if the two cut-offs are equal.

</DOC>
<DOC>
<DOCNO> 101325 </DOCNO>
Subnormal embedding theorems for groups


  In this paper we establish some subnormal embeddings of groups into groups
with additional properties; in particular embeddings of countable groups into
2-generated groups with some extra properties. The results obtained are
generalizations of theorems of P. Hall, R. Dark, B. Neumann, Hanna Neumann, G.
Higman on embeddings of that type. Considering subnormal embeddings of finite
groups into finite groups with additional properties we bring some illustration
to a result of H. Heineken and J. Lennox.

</DOC>
<DOC>
<DOCNO> 13847 </DOCNO>
Towards a realistic microscopic description of highway traffic


  Simple cellular automata models are able to reproduce the basic properties of
highway traffic. The comparison with empirical data for microscopic quantities
requires a more detailed description of the elementary dynamics. Based on
existing cellular automata models we propose an improved discrete model
incorporating anticipation effects, reduced acceleration capabilities and an
enhanced interaction horizon for braking. The modified model is able to
reproduce the three phases (free-flow, synchronized, and stop-and-go) observed
in real traffic. Furthermore we find a good agreement with detailed empirical
single-vehicle data in all phases.

</DOC>
<DOC>
<DOCNO> 69621 </DOCNO>
The general QCD parametrization and the large N(c) description:Some


  Stimulated by a recent paper by Buchmann and Lebed,a comparison is presented
of the two methods mentioned in the title for treating hadron properties in
QCD.Doubts arise on the equivalence of the large N(c) description to real
QCD.[PACS:12.38.Aw;11.15.Pg;12.40.Yx;13.40.Dk]

</DOC>
<DOC>
<DOCNO> 179026 </DOCNO>
Faddeev description of two-hole one-particle motion and the


  The Faddeev technique is employed to address the problem of describing the
influence of both particle-particle and particle-hole phonons on the
single-particle self-energy. The scope of the few-body Faddeev equations is
extended to describe the motion of two-hole one-particle (two-particle
one-hole) excitations. This formalism allows to sum both particle-particle and
particle-hole phonons, obtained separately in the Random Phase Approximation.
The appearance of spurious solutions for the present application of the Faddeev
method is related to the inclusion of a consistent set of diagrams. The
formalism presented here appears practical for finite nuclei and achieves a
simultaneous inclusion of particle-particle and particle-hole phonons to all
orders while the spurious solutions are properly eliminated.

</DOC>
<DOC>
<DOCNO> 169858 </DOCNO>
A proof that measured data and equations of quantum mechanics can be


  The design and operation of a quantum-mechanical device as a laboratory
instrument puts models written in equations of quantum mechanics in contact
with instruments. This contact is recordable in files of a Classical Digital
Process-control Computer (CPC) used both to calculate with the equations and to
manage the instruments. By noticing that equations and instruments make contact
in a CPC, we rewrite equations of quantum mechanics to explicitly include
functions of CPC-commands to the instruments. This sets up a proof that a
scientist's choice in linking mathematical models to instruments is
unresolvable without guesswork to narrow the set of models from which one is to
be chosen.
  As for implications of the proof, scientists inherit choices from the past
and frame choices for the future, choices open to guesswork and visible in CPC
files. To picture these choices, we adapt colored Petri nets, and the
availability of these net fragments makes choice and guesswork part and parcel
of physics.
  Net fragments as a means of expressing guess-demanding choices are applied to
portray guesswork needed in testing and calibrating a quantum computer. The
sample size required to test a quantum gate in a quantum computer is shown to
grow as the inverse square of the error allowed in implementing the gate.

</DOC>
<DOC>
<DOCNO> 67850 </DOCNO>
Meson Properties in the 1/N_c-corrected NJL model


  Properties of mesons are investigated within the Nambu--Jona-Lasinio model.
We include meson-loop corrections, which are generated via a systematic
1/N_c-expansion in next-to-leading order. We show that our scheme is consistent
with chiral symmetry, in particular with the Goldstone theorem and the
Gell-Mann Oakes Renner relation. The numerical part focuses on the pion and the
rho-meson sector. For the latter the 1/N_c-corrections are crucial in order to
include the dominant rho -> pi pi-decay channel, while the leading-order
approximation only contains unphysical q\bar q-decay channels. We show that a
satisfactory description of the pion electromagnetic form factor can be
obtained. Similarities and differences to hadronic models are discussed.

</DOC>
<DOC>
<DOCNO> 152109 </DOCNO>
An overview of new supersymmetric gauge theories with 2-form gauge


  An overview of new 4d supersymmetric gauge theories with 2-form gauge
potentials constructed by various authors during the past five years is given.
The key role of three particular types of interaction vertices is emphasized.
These vertices are used to develop a connecting perspective on the new models
and to distinguish between them. One example is presented in detail to
illustrate characteristic features of the models. A new result on couplings of
2-form gauge potentials to Chern-Simons forms is presented.

</DOC>
<DOC>
<DOCNO> 150439 </DOCNO>
Quantum (in)stability of dilatonic AdS backgrounds and holographic


  Stability of dilatonic AdS spaces due to quantum effects of dilaton coupled
conformal matter is considered. When such spaces do not exist on classical
level, their dynamical generation occurs. Explicit examples corresponding to
quantum creation of d4 dilatonic AdS Universe and of d2 dilatonic AdS Black
Hole (BH) are presented. Motivated by holographic RG, in the similar approach
the complete d5 effective action is discussed. The intermediate region where it
is the sum of two parts: bulk (classical gravity) and boundary quantum action
is investigated. The effective equations solution representing d5 AdS Universe
with warp scale factor is found. Four-dimensional de Sitter or AdS world is
generated on the boundary of such Universe as a result of quantum effects.

</DOC>
<DOC>
<DOCNO> 68654 </DOCNO>
Signals of CP Violation in Distributions of Top-Quark Decay Products at


  Angular and energy distributions for leptons and bottom quarks in the process
e+e- --> t tbar --> l/b ... have been calculated assuming the most general
top-quark couplings. The double distributions depend both on modification of
the top-quark production and tbW decay vertices. However, the leptonic angular
distribution turned out to be insensitive to non-standard parts of tbW vertex.
The method of optimal observables have been used to estimate sensitivity of
future measurements at linear e+e- colliders

</DOC>
<DOC>
<DOCNO> 152350 </DOCNO>
Mass Spectra of N=2 Supersymmetric SU(n) Chern-Simons-Higgs Theories


  An algebraic method is used to work out the mass spectra and symmetry
breaking patterns of general vacuum states in N=2 supersymmetric SU(n)
Chern-Simons-Higgs systems with the matter fields being in the adjoint
representation. The approach provides with us a natural basis for fields, which
will be useful for further studies in the self-dual solutions and quantum
corrections. As the vacuum states satisfy the SU(2) algebra, it is not
surprising to find that their spectra are closely related to that of angular
momentum addition in quantum mechanics. The analysis can be easily generalized
to other classical Lie groups.

</DOC>
<DOC>
<DOCNO> 120183 </DOCNO>
The Size and Shape of Voids in Three-Dimensional Galaxy Surveys


  The sizes and shapes of voids in a galaxy survey depend not only on the
physics of structure formation, but also on the sampling density of the survey
and on the algorithm used to define voids. Using an N-body simulation with a
CDM power spectrum, we study the properties of voids in samples with different
number densities of galaxies, both in redshift space and in real space. When
voids are defined as regions totally empty of galaxies, their characteristic
volume is strongly dependent on sampling density; when they are defined as
regions whose density is 0.2 times the mean galaxy density, the dependence is
less strong. We compare two void-finding algorithms, one in which voids are
nonoverlapping spheres, and one, based on the algorithm of Aikio and Mahonen,
which does not predefine the shape of a void. Regardless of the algorithm
chosen, the characteristic void size is larger in redshift space than in real
space, and is larger for low sampling densities than for high sampling
densities. We define an elongation statistic Q which measures the tendency of
voids to be stretched or squashed along the line of sight. Using this
statistic, we find that at sufficiently high sampling densities (comparable to
the number densities of galaxies brighter than L_*), large voids tend to be
slightly elongated along the line of sight in redshift space.

</DOC>
<DOC>
<DOCNO> 101803 </DOCNO>
Harmonic Maps between Generalized Lagrange Spaces


  In this paper are studied the harmonic maps between two generalized Lagrange
spaces. At the same time, it is proved that the solutions of $C^2$ class of
certain ODEs or PDEs are harmonic maps between certain convenient generalized
Lagrange spaces.

</DOC>
<DOC>
<DOCNO> 70301 </DOCNO>
Neutrino Masses and Leptogenesis from R Parity Violation


  In R parity violating supersymmetry (conserving baryon number B but violating
lepton number L), Majorana neutrino masses may arise at tree level, in one
loop, and in two loops. The L violating interactions work together with the B +
L violating electroweak sphalerons to erase any preexisting B or L asymmetry of
the Universe. To have successful leptogenesis nevertheless, a specific scenario
is proposed.

</DOC>
<DOC>
<DOCNO> 152647 </DOCNO>
Self-dual Chern-Simons solitons in noncommutative space


  We construct exact soliton solutions to the Chern-Simons-Higgs system in
noncommutative space, for non-relativistic and relativistic models. In both
cases we find regular vortex-like solutions to the BPS equations which approach
the ordinary selfdual non-topological and topological solitons when the
noncommutative parameter $\theta$ goes to zero.

</DOC>
<DOC>
<DOCNO> 151355 </DOCNO>
Vector Supersymmetry of 2D Yang-Mills Theory


  The vector supersymmetry of the 2D topological BF model is extended to 2D
Yang-Mills. The consequences of the corresponding Ward identity on the
ultraviolet behavior of the theory are analyzed.

</DOC>
<DOC>
<DOCNO> 121795 </DOCNO>
Morphology and Evolution of LMC Planetary Nebulae


  The LMC is ideal for studying the co-evolution of planetary nebulae (PNe) and
their central stars, in that the debilitating uncertainties of the Galactic PN
distance scale and selection biases from attenuation by interstellar dust do
not apply. We present images and analyze slit-less spectra which were obtained
in a survey of Large Magellanic Cloud PNe. These data on 29 targets were
obtained with HST using the Space Telescope Imaging Spectrograph. The data
permit us to determine the nebular dimensions and morphology in the
monochromatic light of several emission lines, including those that have
traditionally been used for morphological studies in the Galaxy: H-alpha, [N
II] 6583 and [O III] 5007, plus others of varying ionization, including [O I],
He I, and [S II]. Together with the 31 resolved LMC PNe for which monochromatic
images exist in the HST archive, these data show that the incidence of
non-symmetric nebulae, including bipolar nebulae (which is an indicator of
Population I ancestry in the Galaxy), is significantly higher than that
reported for the Galaxy. The onset of asymmetric features appears even in very
young nebulae (with dynamical ages of ~1400 yr), suggesting that at least the
gross features of the nebular morphology may be more closely tied to PN
formation, and that subsequent shaping of the expanding envelope by the
radiation field and wind from the central star may play the lesser role of
amplifying these gross features. There is some evidence of evolution between
two morphological types, in the sense that bipolar core (BC) nebulae may evolve
to pure bipolars late in the PN lifetime.

</DOC>
<DOC>
<DOCNO> 85503 </DOCNO>
A phenomenological approach to quintessence in scalar-tensor gravity


  This talk is based on my work in collaboration with B. Boisseau, D. Polarski,
and A.A. Starobinsky. The most natural and best-motivated alternatives to
general relativity are the so-called "scalar-tensor" theories, in which the
gravitational interaction is mediated not only by a (spin-2) graviton, but also
by a (spin-0) scalar field. We study quintessence in this general framework,
and show that the microscopic Lagrangian of the theory can be unambiguously
reconstructed from two observable cosmological functions of the redshift: the
luminosity distance and the linear density perturbation of dustlike matter. We
also analyze the constraints imposed on the theory by the knowledge of only the
first of these functions, as it will probably be available sooner with a good
accuracy. [The main interest of this very short paper is to give the equations
in the "Brans-Dicke" parametrization.]

</DOC>
<DOC>
<DOCNO> 71124 </DOCNO>
Extended Air Showers and Muon Interactions


  The objective of this work is to report on the influence of muon interactions
on the development of air showers initiated by astroparticles. We make a
comparative study of the different theoretical approaches to muon
bremsstrahlung and muonic pair production interactions. A detailed algorithm
that includes all the relevant characteristics of such processes has been
implemented in the AIRES air shower simulation system. We have simulated ultra
high energy showers in different conditions in order to measure the influence
of these muonic electromagnetic interactions. We have found that during the
late stages of the shower development (well beyond the shower maximum) many
global observables are significantly modified in relative terms when the
mentioned interactions are taken into account. This is most evident in the case
of the electromagnetic component of very inclined showers. On the other hand,
our simulations indicate that the studied processes do not induce significant
changes either in the position of the shower maximum or the structure of the
shower front surface.

</DOC>
<DOC>
<DOCNO> 99664 </DOCNO>
Logarithmic series and Hodge integrals in the tautological ring (with an


  We describe a new perspective on the intersection theory of the moduli space
of curves involving both Virasoro constraints and Gorenstein conditions. The
main result of the paper is the computation of a basic 1-point Hodge integral
series occurring in the tautological ring of the moduli space of nonsingular
curves.
  In the appendix by D. Zagier, "Polynomials arising from the tautological
ring", a detailed study is made of certain polynomials whose coefficients are
intersection numbers on moduli space. The paper and the appendix together
provide proofs of all previously conjectured formulas for 1-point integrals in
the tautological ring, and of natural extensions of these formulas as well.

</DOC>
<DOC>
<DOCNO> 117163 </DOCNO>
Optical interpretation of special relativity and quantum mechanics


  The present work shows that through a suitable change of variables
relativistic dynamics can be mapped to light propagation in a non-homogeneous
medium. A particle's trajectory through the modified space-time is thus
formally equivalent to a light ray and can be derived from a mechanical
equivalent of Fermat's principle. The similarities between light propagation
and mechanics are then extended to quantum mechanics, showing that relativistic
quantum mechanics can be derived from a wave equation in modified space-time.
Non-relativistic results, such as de Broglie's wavelength, Schroedinger
equation and uncertainty principle are shown to be direct consequences of the
theory and it is argued that relativistic conclusions are also possible.

</DOC>
<DOC>
<DOCNO> 13153 </DOCNO>
Waves attractors in rotating fluids: a paradigm for ill-posed Cauchy


  In the limit of low viscosity, we show that the amplitude of the modes of
oscillation of a rotating fluid, namely inertial modes, concentrate along an
attractor formed by a periodic orbit of characteristics of the underlying
hyperbolic Poincar\'e equation. The dynamics of characteristics is used to
elaborate a scenario for the asymptotic behaviour of the eigenmodes and
eigenspectrum in the physically relevant r\'egime of very low viscosities which
are out of reach numerically. This problem offers a canonical ill-posed Cauchy
problem which has applications in other fields.

</DOC>
<DOC>
<DOCNO> 10156 </DOCNO>
Spin Gap of S=1/2 Heisenberg Model on Distorted Diamond Chain


  We study the spin gap of the S=1/2 Heisenberg model on the distorted diamond
chain, which is recently proposed to represent magnetic properties of Cu_3 Cl_6
(H_2 O)_2 2H_8 C_4 SO_2. This model is composed of stacked trimers and has
three kinds of exchange interactions J_1, J_2 and J_3. Using the numerical
diagonalization, we obtain a contour map of the spin gap in the J_2/J_1-J_3/J_1
plane. We argue possible values of the exchange constants based on the contour
map and the observed value of the spin gap.

</DOC>
<DOC>
<DOCNO> 121179 </DOCNO>
The Local Ly-alpha Forest: HI in Nearby Intergalactic Space


  Detecting HI using redshifted Ly-alpha absorption lines is 1e6 times more
sensitive than using the 21cm emission line. We review recent discoveries of HI
Ly-alpha absorbers made with the Hubble Space Telescope (HST) which have
allowed us a first glimpse at gas in local intergalactic space between us and
the ``Great Wall''. Despite its mere 2.4m aperture, HST can detect absorbers
with column densities as low as those found using Keck at high-z (log
N(HI)=12.5 1/cm**2). New results that will be discussed include: the evolution
of absorbers with redshift, the location of absorbers relative to galaxies
(including the two-point correlation function for absorbers), the metallicity
of absorbers far from galaxies, and the discovery of hot 1e5-1e6 K
(shock-heated?) absorbers. The unique ability of VLA HI observations in
discovering the nearest galaxies to these absorbers is stressed.

</DOC>
<DOC>
<DOCNO> 150417 </DOCNO>
Some Reflections on Moduli, Their Stabilization and Cosmology


  We review some aspects of moduli in string theory. We argue that one should
focus on {\it approximate moduli spaces}, and that there is evidence that such
spaces exist non-perturbatively. We ask what it would mean for string theory to
predict low energy supersymmetry. Aspects of two proposed mechanisms for fixing
the moduli are discussed, and solutions to certain cosmological problems
associated with moduli are proposed.

</DOC>
<DOC>
<DOCNO> 170791 </DOCNO>
No-cloning theorem and teleportation criteria for quantum continuous


  We discuss the criteria presently used for evaluating the efficiency of
quantum teleportation schemes for continuous variables. Using an argument based
upon the difference between 1-to-2 quantum cloning (quantum duplication) and
1-to-infinity cloning (classical measurement), we show that a fidelity value
larger than 2/3 is required for successful quantum teleportation of coherent
states. This value has not been reached experimentally so far.

</DOC>
<DOC>
<DOCNO> 99610 </DOCNO>
On the size of Diophantine m-tuples


  Let n be a nonzero integer and assume that a set S of positive integers has
the property that xy+n is a perfect square whenever x and y are distinct
elements of S. In this paper we find some upper bounds for the size of the set
S. We prove that if |n| <= 400 then |S| <= 32, and if |n| > 400 then |S| <
267.81 log|n| (log log|n|)^2. The question whether there exists an absolute
bound (independent on n) for |S| still remains open.

</DOC>
<DOC>
<DOCNO> 151915 </DOCNO>
Calculation of Ground State Energy for Confined Fermion Fields


  A method for renormalization of the Casimir energy of confined fermion fields
in (1+1)D is proposed. It is based on the extraction of singularities which
appear as poles at the point of physical value of the regularization parameter,
and subsequent compensation of them by means of redefinition of the "bare"
constants. A finite ground state energy of the two-phase hybrid model of
fermion bag with chiral boson-fermion interaction is calculated as the function
of the bag's size.

</DOC>
<DOC>
<DOCNO> 69367 </DOCNO>
Tau Neutrinos Underground: Signals of $\nu_\mu \to \nu_\tau$


  The appearance of high energy tau neutrinos due to $\nu_\mu \to \nu_\tau$
oscillations of extragalactic neutrinos can be observed by measuring the
neutrino induced upward hadronic and electromagnetic showers and upward muons.
We evaluate quantitatively the tau neutrino regeneration in the Earth for a
variety of extragalactic neutrino fluxes. Charged-current interactions of the
upward tau neutrinos below and in the detector, and the subsequent tau decay
create muons or hadronic and electromagnetic showers. The background for these
events are muon neutrino and electron neutrino charged-current and
neutral-current interactions, where in addition to extragalactic neutrinos, we
consider atmospheric neutrinos. We find significant signal to background ratios
for the hadronic/electromagnetic showers with energies above 10 TeV to 100 TeV
initiated by the extragalactic neutrinos. We show that the tau neutrinos from
point sources also have the potential for discovery above a 1 TeV threshold. A
kilometer-size neutrino telescope has a very good chance of detecting the
appearance of tau neutrinos when both muon and hadronic/electromagnetic showers
are detected.

</DOC>
<DOC>
<DOCNO> 100009 </DOCNO>
Gorenstein models of del Pezzo surfaces of degree 1 over Dedekind


  Let R be a Dedekind scheme, $\nu$ its generic point, X and V del Pezzo
surfaces of degree 1 over R that are Gorenstein Mori fiber spaces (as 3-folds
germs over the ground field). We study birational maps $\phi:X\dasharrow V$
over R which are isomorphisms over the generic point of R. We put down normal
forms of such transformations (in suitable coordinates) and give some
properties of X and V. In particular, we prove the uniqueness of a smooth
model.

</DOC>
<DOC>
<DOCNO> 102794 </DOCNO>
Nonlinear Supersymmetry, Quantum Anomaly and Quasi-Exactly Solvable


  The nonlinear supersymmetry of one-dimensional systems is investigated in the
context of the quantum anomaly problem. Any classical supersymmetric system
characterized by the nonlinear in the Hamiltonian superalgebra is
symplectomorphic to a supersymmetric canonical system with the holomorphic form
of the supercharges. Depending on the behaviour of the superpotential, the
canonical supersymmetric systems are separated into the three classes. In one
of them the parameter specifying the supersymmetry order is subject to some
sort of classical quantization, whereas the supersymmetry of another extreme
class has a rather fictive nature since its fermion degrees of freedom are
decoupled completely by a canonical transformation. The nonlinear supersymmetry
with polynomial in momentum supercharges is analysed, and the most general
one-parametric Calogero-like solution with the second order supercharges is
found. Quantization of the systems of the canonical form reveals the two
anomaly-free classes, one of which gives rise naturally to the quasi-exactly
solvable systems. The quantum anomaly problem for the Calogero-like models is
``cured'' by the specific superpotential-dependent term of order $\hbar^2$. The
nonlinear supersymmetry admits the generalization to the case of
two-dimensional systems.

</DOC>
<DOC>
<DOCNO> 102749 </DOCNO>
Tensor products of level zero representations


  We define an action of the braid group (associated with a simple Lie algebra)
on the space of $n$-tuples of power series in an indeterminate u, with constant
term zero.
  Using this, we give a sufficient condition for a tensor product of
finite-dimensional representations of quantum affine algebras to be cyclic on
the tensor product of highest weight vectors. In particular, this proves a
generalization of a recently established conjecture of Akasaka and Kashiwara
(see qa/0010293 and qa/0006084).

</DOC>
<DOC>
<DOCNO> 119729 </DOCNO>
Ambipolar Filamentation of Turbulent Magnetic Fields : A numerical


  We present the results of a 2-D, two fluid (ions and neutrals) simulation of
the ambipolar filamentation process, in which a magnetized, weakly ionized
plasma is stirred by turbulence in the ambipolar frequency range. The higher
turbulent velocity of the neutrals in the most ionized regions gives rise to a
non-linear force driving them out of these regions, so that the initial
ionization inhomogeneities are strongly amplified. This effect, the ambipolar
filamentation, causes the ions and the magnetic flux to condense and separate
from the neutrals, resulting in a filamentary structure.

</DOC>
<DOC>
<DOCNO> 118917 </DOCNO>
The SOFIA Telescope


  The SOFIA telescope as the heart of the observatory is a major technological
challenge. I present an overview on the astro-nomical and scientific
requirements for such a big airborne observatory and demonstrate the impact of
these requirements on the layout of SOFIA, in particular on the telescope
design as it is now. Selected components of the telescope will be de-scribed in
their context and functionality. The current status of the telescope is
presented.

</DOC>
<DOC>
<DOCNO> 10399 </DOCNO>
Theory of Magnetic Anisotropy in III_{1-x}Mn_{x}V Ferromagnets


  We present a theory of magnetic anisotropy in ${\rm III}_{1-x}{\rm
Mn}_{x}{\rm V}$ diluted magnetic semiconductors with carrier-induced
ferromagnetism. The theory is based on four and six band envelope functions
models for the valence band holes and a mean-field treatment of their exchange
interactions with ${\rm Mn}^{++}$ ions. We find that easy-axis reorientations
can occur as a function of temperature, carrier density $p$, and strain. The
magnetic anisotropy in strain-free samples is predicted to have a $p^{5/3}$
hole-density dependence at small $p$, a $p^{-1}$ dependence at large $p$, and
remarkably large values at intermediate densities. An explicit expression,
valid at small $p$, is given for the uniaxial contribution to the magnetic
anisotropy due to unrelaxed epitaxial growth lattice-matching strains. Results
of our numerical simulations are in agreement with magnetic anisotropy
measurements on samples with both compressive and tensile strains. We predict
that decreasing the hole density in current samples will lower the
ferromagnetic transition temperature, but will increase the magnetic anisotropy
energy and the coercivity.

</DOC>
<DOC>
<DOCNO> 116424 </DOCNO>
The Helical Wiggler


  There is not a unique solution to the electro- or magnetostatic problem where
the "boundary condition" is merely a specification of the fields along a line.
As a practical example, we consider the case where it is desired to have a
magnetic field that that traces a helix about the z axis.

</DOC>
<DOC>
<DOCNO> 8342 </DOCNO>
Localization and delocalization in dirty superconducting wires


  We present Fokker-Planck equations that describe transport of heat and spin
in dirty unconventional superconducting quantum wires. Four symmetry classes
are distinguished, depending on the presence or absence of time-reversal and
spin rotation invariance. In the absence of spin-rotation symmetry, heat
transport is anomalous in that the mean conductance decays like $1/\sqrt{L}$
instead of exponentially fast for large enough length $L$ of the wire. The
Fokker-Planck equations in the presence of time-reversal symmetry are solved
exactly and the mean conductance for quasiparticle transport is calculated for
the crossover from the diffusive to the localized regime.

</DOC>
<DOC>
<DOCNO> 122885 </DOCNO>
K band monitoring of GRS 1915+105 during 1999/2000


  We report on long-term K band photometry of the galactic microquasar GRS
1915+105 since March 1999. We see variations of more than 1 mag, which are
seemingly correlated with variations in X-ray intensity and spectral slope.

</DOC>
<DOC>
<DOCNO> 102277 </DOCNO>
Recurrence of Distributional Limits of Finite Planar Graphs


  Suppose that $G_j$ is a sequence of finite connected planar graphs, and in
each $G_j$ a special vertex, called the root, is chosen randomly-uniformly. We
introduce the notion of a distributional limit $G$ of such graphs. Assume that
the vertex degrees of the vertices in $G_j$ are bounded, and the bound does not
depend on $j$. Then after passing to a subsequence, the limit exists, and is a
random rooted graph $G$. We prove that with probability one $G$ is recurrent.
The proof involves the Circle Packing Theorem. The motivation for this work
comes from the theory of random spherical triangulations.

</DOC>
<DOC>
<DOCNO> 152316 </DOCNO>
Field theory insight from the AdS/CFT correspondence


  A survey of ideas, techniques and results from d=5 supergravity for the
conformal and mass-perturbed phases of d=4 ${\cal N}$=4 Super-Yang-Mills theory

</DOC>
<DOC>
<DOCNO> 9112 </DOCNO>
Investigation of routes and funnels in protein folding by free energy


  We use a free energy functional theory to elucidate general properties of
heterogeneously ordering, fast folding proteins, and we test our conclusions
with lattice simulations. We find that both structural and energetic
heterogeneity can lower the free energy barrier to folding. Correlating
stronger contact energies with entropically likely contacts of a given native
structure lowers the barrier, and anticorrelating the energies has the reverse
effect. Designing in relatively mild energetic heterogeneity can eliminate the
barrier completely at the transition temperature. Sequences with native
energies tuned to fold uniformly, as well as sequences tuned to fold by a
single or a few routes, are rare. Sequences with weak native energetic
heterogeneity are more common; their folding kinetics is more strongly
determined by properties of the native structure. Sequences with different
distributions of stability throughout the protein may still be good folders to
the same structure. A measure of folding route narrowness is introduced which
correlates with rate, and which can give information about the intrinsic biases
in ordering due to native topology. This theoretical framework allows us to
systematically investigate the coupled effects of energy and topology in
protein folding, and to interpret recent experiments which investigate these
effects.

</DOC>
<DOC>
<DOCNO> 150436 </DOCNO>
Invariance Theorems for Supersymmetric Yang-Mills Theories


  We consider quantum mechanical Yang-Mills theories with eight supercharges
and a $Spin(5) \times SU(2)_R$ flavor symmetry. We show that all normalizable
ground states in these gauge theories are invariant under this flavor symmetry.
This includes, as a special case, all bound states of D0-branes and D4-branes.
As a consequence, all bound states of D0-branes are invariant under the
$Spin(9)$ flavor symmetry. When combined with index results, this implies that
the bound state of two D0-branes is unique.

</DOC>
<DOC>
<DOCNO> 102486 </DOCNO>
Indecomposable almost free modules - the local case


  Let R be a countable, principal ideal domain which is not a field and A be a
countable R-algebra which is free as an R-module. Then we will construct an
aleph_1-free R-module G of rank aleph_1 with endomorphism algebra End_RG=A .
Clearly the result does not hold for fields. Recall that an R-module is
aleph_1-free if all its countable submodules are free, a condition closely
related to Pontryagin's theorem. This result has many consequences, depending
on the algebra A in use. For instance, if we choose A=R, then clearly G is an
indecomposable `almost free' module. The existence of such modules was unknown
for rings with only finitely many primes like R=Z_{(p)}, the integers localized
at some prime p. The result complements a classical realization theorem of
Corner's showing that any such algebra is an endomorphism algebra of some
torsion-free, reduced R-module G of countable rank. Its proof is based on new
combinatorial-algebraic techniques related with what we call rigid
tree-elements coming from a module generated over a forest of trees.

</DOC>
<DOC>
<DOCNO> 40515 </DOCNO>
Light resonances in Ks K pi and eta pi pi final states in gamma gamma


  The e+e- -> e+e- Ks K+- pi-+ e+e- -> e+e- eta pi+ pi- and final states are
studied with the L3 detector at LEP using data collected at centre-of-mass
energies from 183 GeV up to 202 GeV. The mass spectrum of the Ks K+- pi-+ final
state shows an enhancement around 1470MeV, which is identified with the
pseudoscalar meson eta(1440). This state is observed in gamma gamma collisions
for the first time and its two-photon width is measured to be Gamma_gamma
gamma(eta(1440))x BR(eta(1440)->KK pi)= 212 +/- 50(stat) +/- 23(sys)eV. Clear
evidence is also obtained for the formation of the axial vector mesons f1(1420)
and f1(1285). In the eta pi+ pi- channel the f1(1285) is observed, and upper
limits for the formation of eta(1440) and eta(1295) are obtained.

</DOC>
<DOC>
<DOCNO> 102775 </DOCNO>
Invitation to higher local fields, Part I, section 10: Explicit higher


  This is a presentation of explicit methods to construct higher local class
field theory by using topological K-groups, explicit symbols and a
generalization of Neukirch-Hazewinkel's axiomatic approaches. The existence
theorem is discussed as well.

</DOC>
<DOC>
<DOCNO> 100241 </DOCNO>
Heat Invariant E_2 for Nonminimal Operator on Manifolds with Torsion


  Computer algebra methods are applied to investigation of spectral asymptotics
of elliptic differential operators on curved manifolds with torsion and in the
presence of a gauge field. In this paper we present complete expressions for
the second coefficient (E_2) in the heat kernel expansion for nonminimal
operator on manifolds with nonzero torsion. The expressions were computed for
general case of manifolds of arbitrary dimension n and also for the most
important for E_2 case n=2. The calculations have been carried out on PC with
the help of a program written in C.

</DOC>
<DOC>
<DOCNO> 121830 </DOCNO>
K-band Spectroscopy of Clusters in NGC 4038/4039


  Integral field spectroscopy in the K-band (1.9-2.4um) was performed on four
IR-bright star clusters and the two nuclei in NGC 4038/4039 (``The Antennae'').
Two of the clusters are located in the overlap region of the two galaxies, and
together comprise ~25% of the total 15um and ~10% of the total 4.8 GHz emission
from this pair of merging galaxies. The other two clusters, each of them
spatially resolved into two components, are located in the northern galaxy, one
in the western and one in the eastern loop of blue clusters. Comparing our
analysis of Brgamma, CO band-heads, He I (2.058um), Halpha (from archival HST
data), and V-K colors with stellar population synthesis models indicates that
the clusters are extincted (A_V ~ 0.7 - 4.3 mags) and young, displaying a
significant age spread (4-13 Myrs). The starbursts in the nuclei are much older
(65 Myrs), with the nucleus of NGC 4038 displaying a region of recent star
formation northward of its K-band peak. Using our derived age estimates and
assuming the parameters of the IMF (Salpeter slope, upper mass cut-off of 100
M_sun, Miller-Scalo between 1 M_sun and 0.1 M_sun), we find that the clusters
have masses between 0.5 and 5 * 10^6M_sun.

</DOC>
<DOC>
<DOCNO> 8217 </DOCNO>
Topological approach to Luttinger's theorem and the Fermi surface of a


  A non-perturbative proof of Luttinger's theorem, based on a topological
argument, is given for Fermi liquids in arbitrary dimensions. Application to
the Kondo lattice shows that even the completely localized spins do contribute
to the Fermi sea volume as electrons, whenever the system can be described as a
Fermi liquid.

</DOC>
<DOC>
<DOCNO> 152107 </DOCNO>
Monopoles and dyons in SO(3) gauged Skyrme models


  Three dimensional SO(3) gauged Skyrme models characterised by specific
potentials imposing special asymptotic values on the chiral field are
considered. These models are shown to support finite energy solutions with
nonvanishing magnetic and electrix flux, whose energies are bounded from below
by two distinct charges - the magnetic (monopole) charge and a non-integer
version of the Baryon charge. Unit magnetic charge solutions are constructed
numerically and their properties characterised by the chosen asymptotics and
the Skyrme coupling are studied. For a particular value of the chosen
asymptotics, charge-2 axially symmetric solutions are also constructed and the
attractive nature of the like-monopoles of this system are exhibited. As an
indication towards the possible existence of large clumps of monopoles, some
consideration is given to axially symmetric monopoles of charges-2,3,4.

</DOC>
<DOC>
<DOCNO> 69798 </DOCNO>
Lattice regularization of chiral gauge theories to all orders of


  In the framework of perturbation theory, it is possible to put chiral gauge
theories on the lattice without violating the gauge symmetry or other
fundamental principles, provided the fermion representation of the gauge group
is anomaly-free. The basic elements of this construction (which starts from the
Ginsparg-Wilson relation) are briefly recalled and the exact cancellation of
the gauge anomaly, at any fixed value of the lattice spacing and for any
compact gauge group, is then proved rigorously through a recursive procedure.

</DOC>
<DOC>
<DOCNO> 71191 </DOCNO>
Hot or dense matter


  I review some properties of hot and/or dense releativistic matter. This
review is aimed at a general audience of particle physicists.

</DOC>
<DOC>
<DOCNO> 101962 </DOCNO>
Deformation theory of singular symplectic n-folds


  The notion of a holomorphically symplectic manifold can be generalized to the
singular one. This paper studies the birational contraction maps between
symplectic varieties, and then describes the deformation of a symplectic
variety which has a symplectic resolution. Some examples are also included.

</DOC>
<DOC>
<DOCNO> 8608 </DOCNO>
Simultaneously imaging of dielectric properties and topography in a


  We use a near-field scanning microwave microscope to simultaneously image the
dielectric constant, loss tangent, and topography in a PbTiO_3 crystal. By this
method, we study the effects of the local dielectric constant and loss tangent
in the geometry of periodic domains on the measured resonant frequency, and
quality factor. We also carry out theoretical calculations and the results
agree well with the experimental data and reveal the anisotropic nature of
dielectric constant.

</DOC>
<DOC>
<DOCNO> 117212 </DOCNO>
Hydration of methanol in water. A DFT-based molecular dynamics study


  We studied the hydration of a single methanol molecule in aqueous solution by
first-principle DFT-based molecular dynamics simulation. The calculations show
that the local structural and short-time dynamical properties of the water
molecules remain almost unchanged by the presence of the methanol, confirming
the observation from recent experimental structural data for dilute solutions.
We also see, in accordance with this experimental work, a distinct shell of
water molecules that consists of about 15 molecules. We found no evidence for a
strong tangential ordering of the water molecules in the first hydration shell.

</DOC>
<DOC>
<DOCNO> 152325 </DOCNO>
Noncommutative Vortex Solitons


  We consider the noncommutative Abelian-Higgs theory and investigate general
static vortex configurations including recently found exact multi-vortex
solutions. In particular, we prove that the self-dual BPS solutions cease to
exist once the noncommutativity scale exceeds a critical value. We then study
the fluctuation spectra about the static configuration and show that the exact
non BPS solutions are unstable below the critical value. We have identified the
tachyonic degrees as well as massless moduli degrees. We then discuss the
physical meaning of the moduli degrees and construct exact time-dependent
vortex configurations where each vortex moves independently. We finally give
the moduli description of the vortices and show that the matrix nature of
moduli coordinates naturally emerges.

</DOC>
<DOC>
<DOCNO> 118134 </DOCNO>
Compton dragged gamma-ray bursts: the spectrum


  We calculate the spectrum resulting from the interaction of a fireball with
ambient soft photons. These photons are assumed to be produced by the walls of
a funnel in a massive star. By parameterizing the radial dependence of the
funnel temperature we calculate the deceleration of the fireball
self-consistently, taking into account the absorption of high energy gamma-rays
due to interaction with the softer ambient photons. The resulting spectrum is
peaked at energies in agreement with observations, has a nu^2 slope in the
X-ray band and a steep power-law high energy tail.

</DOC>
<DOC>
<DOCNO> 122253 </DOCNO>
Long-time behavior and relaxation of power-law correlation in


  Long-time behavior of spatial power-law correlation in one-dimensional
self-gravitating system is numerically investigated. It is found that the
power-law structure persists even after the system is virialized. The structure
gradually disappears owing to energy exchange among particles. Energy
distribution is quasi-stationary after the system is virialized.

</DOC>
<DOC>
<DOCNO> 120660 </DOCNO>
The Modified Weighted Slab Technique: Models and Results


  In an attempt to understand the source and propagation of galactic cosmic
rays we have employed the Modified Weighted Slab technique along with recent
values of the relevant cross sections to compute primary to secondary ratios
including B/C and Sub-Fe/Fe for different galactic propagation models. The
models that we have considered are the disk-halo diffusion model, the dynamical
halo wind model, the turbulent diffusion model and a model with minimal
reacceleration. The modified weighted slab technique will be briefly discussed
and a more detailed description of the models will be given. We will also
discuss the impact that the various models have on the problem of anisotropy at
high energy and discuss what properties of a particular model bear on this
issue.

</DOC>
<DOC>
<DOCNO> 8134 </DOCNO>
New way to achieve chaotic synchronization in spatially extended systems


  We study the spatio-temporal behavior of simple coupled map lattices with
periodic boundary conditions. The local dynamics is governed by two maps,
namely, the sine circle map and the logistic map respectively. It is found that
even though the spatial behavior is irregular for the regularly coupled
(nearest neighbor coupling) system, the spatially synchronized (chaotic
synchronization) as well as periodic solution may be obtained by the
introduction of three long range couplings at the cost of three nearest
neighbor couplings.

</DOC>
<DOC>
<DOCNO> 178408 </DOCNO>
Dileptons and hadron spectral functions in heavy-ion collisions


  We briefly review the dilepton experiments at BEVALAC/SIS and SPS energies
for p+p, p+A and A+A collisions as well as our present understanding of the
data within transport theoretical simulations. Since dileptons from p+A and A+A
collisions in particular probe the in-medium spectral functions of vector
mesons, a novel semiclassical off-shell transport approach is introduced on the
basis of the Kadanoff-Baym equations that describes the dynamical evolution of
broad hadron spectral functions. The implications of the off-shell dynamics --
relative to the conventional on-shell transport dynamics -- are discussed for
proton spectra, high energy $\gamma$, pion, kaon and antikaon production from
GANIL to AGS energies in comparison to experimental data.

</DOC>
<DOC>
<DOCNO> 169641 </DOCNO>
The space of local equivalence classes of mixed two-qubit states


  This paper is withdrawn by the author. It is superseded by Makhlin's paper
quant-ph/0002045.

</DOC>
<DOC>
<DOCNO> 72142 </DOCNO>
Determination of Unitarity Triangle parameters: where do we stand ?


  In this note I review the current determination of the unitarity triangle
parameters by using the theoretical and experimental information available in
summer 2000.

</DOC>
<DOC>
<DOCNO> 84494 </DOCNO>
Why we live in 3 Dimensions


  A Cantorian fractal spacetime, a family member of von Neumann's
noncommutative geometry is introduced as a geometry underlying a new relativity
theory which is similar to the relation between general relativity and
Riemannian geometry. Based on this model and the new relativity theory an
ensemble distribution of all the dimensions of quantum spacetime is derived
with the help of Fermat grand theorem. The calculated average dimension is very
close to the value of $4+\phi^3 $ (where $\phi$ is the golden mean) obtained by
El Naschie on the basis of a different approach. It is shown that within the
framework of the new relativity the cosmological constant problem is
nonexistent, since the Universe self-organizes and self-tunes according to the
renormalization group (RG) flow with respect to a local scaling microscopic
arrow of time. This implies that the world emerged as a result of a
non-equilibrium process of self-organized critical phenomena launched by vacuum
fluctuations in Cantorian fractal spacetime $\cal E^{\infty}$. It is shown that
we are living in a metastable vacuum and are moving towards a fixed point ($ D$
= 4+$\phi^3$) of the RG. After reaching this point, a new phase transition will
drive the universe to a quasi-crystal phase of the lower average dimension of
$\phi^3$.

</DOC>
<DOC>
<DOCNO> 71735 </DOCNO>
The Development of Equilibrium After Preheating


  We present a fully nonlinear study of the development of equilibrium after
preheating. Preheating is the exponentially rapid transfer of energy from the
nearly homogeneous inflaton field to fluctuations of other fields and/or the
inflaton itself. This rapid transfer leaves these fields in a highly nonthermal
state with energy concentrated in infrared modes. We have performed lattice
simulations of the evolution of interacting scalar fields during and after
preheating for a variety of inflationary models. We have formulated a set of
generic rules that govern the thermalization process in all of these models.
Notably, we see that once one of the fields is amplified through parametric
resonance or other mechanisms it rapidly excites other coupled fields to
exponentially large occupation numbers. These fields quickly acquire nearly
thermal spectra in the infrared, which gradually propagates into higher
momenta. Prior to the formation of total equilibrium, the excited fields group
into subsets with almost identical characteristics (e.g. group effective
temperature). The way fields form into these groups and the properties of the
groups depend on the couplings between them. We also studied the onset of chaos
after preheating by calculating the Lyapunov exponent of the scalar fields.

</DOC>
<DOC>
<DOCNO> 118357 </DOCNO>
High Velocity Star Formation in the LMC


  Light-echo measurements show that SN1987A is 425 pc behind the LMC disk. It
is continuing to move away from the disk at $18 \kms$. Thus, it has been
suggested that SN1987A was ejected from the LMC disk. However, SN1987A is a
member of a star cluster, so this entire cluster would have to have been
ejected from the disk. We show that the cluster was formed in the LMC disk,
with a velocity perpendicular to the disk of about $50 \kms$. Such high
velocity formation of a star cluster is unusual, having no known counterpart in
the Milky Way.

</DOC>
<DOC>
<DOCNO> 100738 </DOCNO>
Octonionic Hermitian Matrices with Non-Real Eigenvalues


  We extend previous work on the eigenvalue problem for Hermitian octonionic
matrices by discussing the case where the eigenvalues are not real, giving a
complete treatment of the 2x2 case, and summarizing some prelimenary results
for the 3x3 case.

</DOC>
<DOC>
<DOCNO> 100614 </DOCNO>
Some Fundamental Properties of Successive Convex Relaxation Methods on


  General Successive Convex Relaxation Methods (SRCMs) can be used to compute
the convex hull of any compact set, in an Euclidean space, described by a
system of quadratic inequalities and a compact convex set which is not very
complicated. Linear Complementarity Problems (LCPs) make an interesting and
rich class of structured nonconvex optimization problems. In this paper, we
study a few of the specialized lift-and-project methods and some of the
possible ways of applying the general SCRMs to LCPs and related problems.

</DOC>
<DOC>
<DOCNO> 120044 </DOCNO>
Extraplanar diffuse ionized gas in a small sample of nearby edge-on


  We present narrowband H-alpha imaging data of a small survey of nearby
edge-on spiral galaxies, aiming at the detection of `extraplanar' diffuse
ionized gas (DIG). A few of our studied edge-on spirals show signs of disk-halo
interaction (DHI), where extended line emission far above the galactic plane of
these galaxies is detected. In some cases an extraplanar diffuse ionized gas
(eDIG) layer is discovered, e.g., NGC4634, NGC 3044, while other galaxies show
only filamentary features reaching into the halo (e.g., IC 2531) and some
galaxies show no sign of eDIG at all. The extraplanar distances of the DIG
layer in our narrowband H-alpha images reach values of z<= 2 kpc above the
galactic plane. The derived star formation rates (SFRs) from the H-alpha flux
of the studied galaxies range from 0.05-0.7 M_{sun}/yr, neglecting a correction
for internal absorption. The variation of the SFR values among our sample
galaxies reflects the diversity of star formation within this sample. A
diagnostic diagram is introduced, which allows to predict the existence of gas
halos in `quiescent' galaxies based on the ratio S_{60}/S_{100} versus L_{FIR}
/ D^2_{25} in this diagram. We compare the positions of the non--starburst
galaxies with starburst galaxies, since these galaxies populate distinct
positions in these diagrams.

</DOC>
<DOC>
<DOCNO> 150781 </DOCNO>
N=(4,4), 2D supergravity in SU(2)xSU(2) harmonic superspace


  We work out the basics of conformal $N=(4,4)$, 2D supergravity in the
$N=(4,4)$, 2D analytic harmonic superspace with two independent sets of
harmonic variables. We define the relevant most general analytic superspace
diffeomorphism group and show that in the flat limit it goes over into the
``large'' $N=(4,4)$, 2D superconformal group. The basic objects of the
supergravity considered are analytic vielbeins covariantizing two
analyticity-preserving harmonic derivatives. For self-consistency they should
be constrained in a certain way. We solve the constraints and show that the
remaining irreducible field content in a WZ gauge amounts to a new short
$N=(4,4)$ Weyl supermultiplet. As in the previously known cases, it involves no
auxiliary fields and the number of remaining components in it coincides with
the number of residual gauge invariances. We discuss various truncations of
this ``master'' conformal supergravity group and its compensations via
couplings to $N=(4,4)$ superconformal matter multiplets. Besides recovering the
standard minimal off-shell $N=(4,4)$ conformal and Poincar\'e supergravity
multiplets, we find, at the linearized level, several new off-shell gauge
representations.

</DOC>
<DOC>
<DOCNO> 122577 </DOCNO>
The effect of turbulent pressure on the p-mode frequencies in stellar


  We have constructed models for the sun at three stages of its evolution: a
zero-age main sequence model, the present sun, and a subgiant model. For each
model, the turbulent pressure and turbulent kinetic energy were calculated from
3-d radiative hydrodynamical simulations (described in the poster by Robinson
et al.), and inserted into the 1-d stellar models. We note that in these
simulations, the turbulent pressure is not a free parameter, but can be
computed from the resulting velocity field. We show the calculated p-mode
frequencies for the model of the present sun, with and without turbulent
pressure, and compare them to the observed solar frequencies. When the
turbulent pressure is included in the models, the calculated frequencies are
brought closer to the observed frequencies in the sun by up to two $\mu Hz$,
strictly from structural effects. The effect of including turbulent pressure on
p-mode frequencies is also shown for the zero-age main sequence model. Our
models also suggest that the importance of turbulent pressure increases as the
star evolves into the subgiant region. We discuss the importance of also
including realistic turbulence as well as radiation in the non-adiabatic
calculation of oscillation frequencies.

</DOC>
<DOC>
<DOCNO> 8136 </DOCNO>
Commensurate and Incommensurate Structure of the Neutron Cross Section


  We study the evolution of the d-wave neutron cross-section with variable
frequency \omega and fixed T (below and above Tc) in two different cuprate
families. The evolution from incommensurate to commensurate to incommensurate
peaks is rather generic within an RPA-like scheme. This behavior seems to be in
reasonable accord with experiments, and may help distinguish between this and
the "stripe" scenario.

</DOC>
<DOC>
<DOCNO> 40006 </DOCNO>
S-wave Kpi scattering in chiral perturbation theory with resonances


  We present a detailed analysis of S-wave Kpi scattering up to 2 GeV, making
use of the resonance chiral Lagrangian predictions together with a suitable
unitarisation method. Our approach incorporates known theoretical constraints
at low and high energies. The present experimental status, with partly
conflicting data from different experiments, is discussed. Our analysis allows
to resolve some experimental ambiguities, but better data are needed in order
to determine the cross-section in the higher-energy range. Our best fits are
used to determine the masses and widths of the relevant scalar resonances in
this energy region.

</DOC>
<DOC>
<DOCNO> 99612 </DOCNO>
The core model for almost linear iterations


  We introduce 0^h (0^handgrenade) as a sharp for an inner model with a proper
class of strong cardinals. If 0^h does not exist then any normal iteration tree
is "almost linear." We exploit this fact to prove the existence of the core
model K in the theory "ZFC + 0^h does not exist." (As of today, non-0^h is
thereby the weakest anti large cardinal assumption under which K can be shown
to exist in ZFC. In this sense we improve earlier work of Dodd, Jensen,
Mitchell, and - partially - Steel.) We indicate that our paper provides the
last step for determining the exact consistency strength of a statement in the
Delfino problem list.

</DOC>
<DOC>
<DOCNO> 178569 </DOCNO>
Searching for the Next Yukawa Phase of QCD


  QCD predicts that the interactions between quarks and gluons change from a
confining to a screened Yukawa form above a critical temperature $T_c\sim 150$
MeV. In this talk, I review some of the key observables in heavy ion reactions
which are being used to search for this new partonic Yukawa phase at SPS and
RHIC. These include collective observables such as $dE_\perp/dyd^2p_\perp$,
meson interferometry, jet quenching, and $J/\psi$ suppression.

</DOC>
<DOC>
<DOCNO> 84150 </DOCNO>
On String Cosmology and de Sitter inflation with massless dilatons and


  Variation of the 4-D string cosmology action with dynamical torsion and
massless dilatons lead to an expression of torsion in terms of massless
dilatons in the case of de Sitter inflation.The solution is approximated
according to the COBE data.

</DOC>
<DOC>
<DOCNO> 116962 </DOCNO>
Status Report on the Low-Energy Demonstration Accelerator (LEDA)


  The 75-keV injector and 6.7-MeV RFQ that comprise the first portion of the
cw, 100-mA proton linac for the accelerator production of tritium (APT) project
have been built and operated. The LEDA RFQ has been extensively tested for
pulsed and cw output-beam currents <=100 mA. Up to 2.2 MW of cw rf power from
the 350-MHz rf system is coupled into the RFQ, including 670 kW for the cw
proton beam. The emittance for a 93-mA pulsed RFQ output beam, as determined
from quadrupole-magnet-scan measurements, is ex x ey = 0.25 x 0.31 (pi mm
mrad)2 [rms normalized]. A follow-on experiment, to intentionally introduce and
measure beam halo on the RFQ output beam, is now being installed.

</DOC>
<DOC>
<DOCNO> 68703 </DOCNO>
Spontaneous Symmetry Breaking at Infinite Momentum without P+ Zero-Modes


  The nonrelativistic interpretation of quantum field theory achieved by
quantization in an infinite momentum frame is spoiled by the inclusion of a
mode of the field carrying p+=0. We therefore explore the viability of doing
without such a mode in the context of spontaneous symmetry breaking (SSB),
where its presence would seem to be most needed. We show that the physics of
SSB in scalar quantum field theory in 1+1 space-time dimensions is accurately
described without a zero-mode.

</DOC>
<DOC>
<DOCNO> 121320 </DOCNO>
A comparison of light and velocity variations in Semiregular variables


  NIR velocity variations are compared with simultaneous visual light curves
for a sample of late-type semiregular variables (SRV). Precise radial velocity
measurements are also presented for the SRV V450 Aql. Our aim is to investigate
the nature of the irregular light changes found in these variables.
  Light and velocity variations are correlated in all stars of our sample.
Based on these results we discuss several possibilities to explain the observed
behavior. We find that pulsation is responsible for large amplitude variations.
In a recent paper Lebzelter (1999) invoked large convective cells to understand
observed velocity variations. This possibility is discussed with respect to the
observed correlation between light and velocity changes. In the light of these
results we investigate the origin of the semiregular variations.

</DOC>
<DOC>
<DOCNO> 39783 </DOCNO>
Study of the Decays B0 --> D(*)+D(*)-


  The decays B0 --> D*+D*-, B0 --> D*+D- and B0 --> D+D- are studied in 9.7
million Y(4S) --> BBbar decays accumulated with the CLEO detector. We determine
Br(B0 --> D*+D*-) = (9.9+4.2-3.3+-1.2)e-4 and limit Br(B0 --> D*+D-) < 6.3e-4
and Br(B0 --> D+D-) < 9.4e-4 at 90% confidence level (CL). We also perform the
first angular analysis of the B0 --> D*+D*- decay and determine that the
CP-even fraction of the final state is greater than 0.11 at 90% CL. Future
measurements of the time dependence of these decays may be useful for the
investigation of CP violation in neutral B meson decays.

</DOC>
<DOC>
<DOCNO> 119349 </DOCNO>
A disk-wind model with correct crossing of all MHD critical surfaces


  The classical Blandford & Payne (1982) model for the magnetocentrifugal
acceleration and collimation of a disk-wind is revisited and refined. In the
original model, the gas is cold and the solution is everywhere subfast
magnetosonic. In the present model the plasma has a finite temperature and the
self-consistent solution of the MHD equations starts with a subslow
magnetosonic speed which subsequently crosses all critical points, at the slow
magnetosonic, Alfven and fast magnetosonic separatrix surfaces. The superfast
magnetosonic solution thus satisfies MHD causality. Downstream of the fast
magnetosonic critical point the poloidal streamlines overfocus towards the axis
and the solution is terminated. The validity of the model to disk winds
associated with young stellar objects is briefly discussed. ~

</DOC>
<DOC>
<DOCNO> 122225 </DOCNO>
UV Spectropolarimetry of Narrow-line Radio Galaxies


  We present the results of UV spectropolarimetry (2000 - 3000A) and far-UV
spectroscopy (1500 - 2000A) of two low-redshift narrow-line radio galaxies
(NLRGs) taken with the Faint Object Spectrograph onboard the Hubble Space
Telescope (HST). Spectropolarimetry of several NLRGs has shown that, by the
presence of broad permitted lines in polarized flux spectrum, they have hidden
quasars seen through scattered light. Imaging polarimetry has shown that NLRGs
including our targets often have large scattering regions of a few kpc to >~10
kpc scale. This has posed a problem about the nature of the scatterers in these
radio galaxies. Their polarized continuum has the spectral index similar to or
no bluer than that of quasars, which favors electrons as the dominant
scattering particles. The large scattering region size, however, favors dust
scattering, because of its higher scattering efficiency compared to electrons.
In this paper, we investigate the polarized flux spectrum over a wide
wavelength range, combining our UV data with previous optical/infrared
polarimetry data. We infer that the scattering would be often caused by opaque
dust clouds in the NLRGs and this would be a part of the reason for the
apparently grey scattering. In the high-redshift radio galaxies, these opaque
clouds could be the proto-galactic subunits inferred to be seen in the HST
images. However, we still cannot rule out the possibility of electron
scattering, which could imply the existence of a large gas mass surrounding
these radio galaxies.

</DOC>
<DOC>
<DOCNO> 121336 </DOCNO>
The Dust Temperature of the "Dusty" Radio Galaxy MG 1019+0535: Evidence


  Radio galaxies characteristically have strong Lya emission lines. However, a
few have Lya equivalent widths that are substantially weaker in relation to
other emission lines. One in particular was studied by Dey etal (1995), MG
1019+0535 (z=2.765). We report on our reduction of Infrared Space Observatory
(ISO}) data in the 160 micron-band for this galaxy. We also compile information
on two other high redshift active galaxies with weak Lya lines, the radio
galaxy TXS 0211-122, and the AGN-starburst galaxy F 10214+4724, to provide a
small weak-Lya line sample. IRAS plus ISO data show that F 10214+4724 has a
temperature 89 +/- 12 K. TXS 0211-122 was not detected in either the
submillimeter or microwave. Submillimeter measurements of MG 1019+0535 (Cimatti
etal 1998) were suggestive of a dust temperature in the range 35 K < T_d < 80
K. However our 2-sigma upper limit on the flux at 160 microns shows that T_d <~
32 K. An energy argument based on observations which constrain the total
optical extinction strongly suggests that the dust temperature must be even
lower; T_d <~ 20 K. We find the contrast between the high-temperature dust in
the active starburst galaxy and the low-temperature dust in the evolved, albeit
active galaxy, is consistent with an expanding cloud of dust. We find that the
temperature range can be reconciled if we are seeing MG 1019+0535 at a
post-starburst age of approx. 500-700 Myr, with the bulk of its dust cloud at a
galactocentric distance R_d >~ 300 kpc.

</DOC>
<DOC>
<DOCNO> 123149 </DOCNO>
The outer ejecta of Eta Carinae


  The nebula around Eta Carinae consists of an inner bipolar structure,
historically called the Homunculus, and the outer ejecta consisting mainly of a
variety of knots of different sizes.They reach out to distances of up to 30"
or0.3pc from Eta Car. With high-resolution long-slit observations we mapped the
outer nebula in order to analyze the global expansion pattern and to model the
three dimensional structure of the ejecta. We find very different expansion
velocities for the knots of the outer ejecta. In some cases they reach up to
values as high as 2000km/s. Typical expansion velocities lie at considerably
lower values around 400-600km/s, i.e., they are comparable to the expansion
velocities found in the Homunculus. Remarkably, the expansion of the outer
ejecta reveals a bidirectional motion pattern, which is consistent with the
bipolar structure of the inner nebula. A general overview of the morphology and
kinematics of the outer ejecta is given and put into context with the structure
and kinematics of the inner part of the nebula, the Homunculus.

</DOC>
<DOC>
<DOCNO> 12044 </DOCNO>
Geometry Selects Highly Designable Structures


  By enumerating all sequences of length 20, we study the designability of
structures in a two-dimensional Hydrophobic-Polar (HP) lattice model in a wide
range of inter-monomer interaction parameters. We find that although the
histogram of designability depends on interaction parameters, the set of highly
designable structures is invariant. So in the HP lattice model the High
Designability should be a purely geometrical feature. Our results suggest two
geometrical properties for highly designable structures, they have maximum
number of contacts and unique neighborhood vector representation. Also we show
that contribution of perfectly stable sequences in designability of structures
plays a major role to make them highly designable.

</DOC>
<DOC>
<DOCNO> 117572 </DOCNO>
Could merged star-clusters build up a small galaxy?


  We investigate the behaviour of a cluster of young massive star clusters
(hereafter super-cluster) in the tidal field of a host galaxy with a
high-resolution particle-mesh code, Superbox. Specifically we want to establish
if and how such super star-clusters merge and carry out a detailed study of the
resulting merger-object. This merger-object shows either the properties of a
compact spherical object or the elongated (`fluffy') shape of dSph-galaxies
depending on the initial concentration of the super-cluster.

</DOC>
<DOC>
<DOCNO> 70709 </DOCNO>
Eikonal propagators and high-energy parton-parton scattering in gauge


  In this paper we consider soft high-energy parton-parton scattering processes
in gauge theories, i.e., elastic scattering processes involving partons at very
high squared energies in the center of mass and small squared transferred
momentum. By a direct resummation of perturbation theory in the limit we are
considering, we derive expressions for the truncated-connected quark
(antiquark) propagator in an external gluon field, as well as for the residue
at the pole of the full unrenormalized propagator, both for scalar and fermion
gauge theories. These are the basic ingredients to derive high-energy
parton-parton scattering amplitudes, using the LSZ reduction formulae and a
functional integral approach. The above procedure is also extended to include
the case in which at least one of the partons is a gluon. The meaning and the
validity of the results are discussed.

</DOC>
<DOC>
<DOCNO> 117559 </DOCNO>
New Models for X-Ray Synchrotron Radiation from the Remnant of Supernova


  Galactic cosmic rays up to energies of around 10^15 eV are assumed to
originate in supernova remnants (SNRs). The shock wave of a young SNR like SN
1006 AD can accelerate electrons to energies greater than 1 TeV, where they can
produce synchrotron radiation in the X-ray band. A new model (SRESC) designed
to model synchrotron X-rays from Type Ia supernovae can constrain values for
the magnetic-field strength and electron scattering properties, with
implications for the acceleration of the unseen ions which dominate the
cosmic-ray energetics. New observations by ASCA, ROSAT, and RXTE have provided
enormously improved data, which now extend to higher X-ray energies. These data
allow much firmer constraints. We will describe model fits to these new data on
SN 1006 AD, emphasizing the physical constraints that can be placed on SNRs and
on the cosmic-ray acceleration process.

</DOC>
<DOC>
<DOCNO> 71971 </DOCNO>
Fluctuations of the transverse energy in Pb+Pb collisions and J/psi


  The observed J/psi suppression in Pb+Pb collisions shows a drop at those
large values of the transverse energy E_T which arise from fluctuations. The
validity of existing models for J/psi suppression can be extended into this
domain of E_T by introducing an ad hoc factor proportional to E_T. We propose a
formalism in which the influence of E_T fluctuations on the J/psi suppression
can be calculated and discuss the conditions under which the ad hoc factor is
obtained.

</DOC>
<DOC>
<DOCNO> 71384 </DOCNO>
Large Extra Dimensions, Sterile neutrinos and Solar Neutrino Data


  Solar, atmospheric and LSND neutrino oscillation results require a light
sterile neutrino, $\nu_B$, which can exist in the bulk of extra dimensions.
Solar $\nu_e$, confined to the brane, can oscillate in the vacuum to the zero
mode of $\nu_B$ and via successive MSW transitions to Kaluza-Klein states of
$\nu_B$. This new way to fit solar data is provided by both low and
intermediate string scale models. From average rates seen in the three types of
solar experiments, the Super-Kamiokande spectrum is predicted with 73%
probability, but dips characteristic of the 0.06 mm extra dimension should be
seen in the SNO spectrum.

</DOC>
<DOC>
<DOCNO> 84169 </DOCNO>
Three dimensional gravity from ISO(2,1) coset models


  Starting from a WZWN action in the ISO(2,1) Poincare' group which describes a
bosonized spinning string in 2+1 Minkowski space-time, we show that a sequence
of non-trivial compactifications leads to the description of a spinless string
which moves in a (linear dilaton) vacuum, AdS_3 or BTZ black hole background.
Other solutions are also obtained and their T-duals analyzed.

</DOC>
<DOC>
<DOCNO> 174534 </DOCNO>
Spatial Distribution of Initial Interactions in High Energy Collisions


  The spatial distribution of interactions in high energy collisions of heavy
nuclei is discussed using the wounded nucleon, binary collision, hard sphere,
and colliding disk parameterizations of interaction densities. The mean radius,
its dispersion, and the eccentricity of the interaction region are calculated
as a function of impact parameter. The eccentricity is of special interest for
comparison to measurements of anisotropic flow. The number of participants and
binary collisions is also tabulated as a function of impact parameter.

</DOC>
<DOC>
<DOCNO> 70480 </DOCNO>
The Meson Spectrum in a Covariant Quark Model


  Within the framework of the instantaneous Bethe-Salpeter equation, we present
a detailed analysis of light meson spectra with respect to various
parameterizations of confinement in Dirac space. Assuming a linearly rising
quark-antiquark potential, we investigate two different spinorial forms (Dirac
structures), namely ${1/2}(\Id\otimes\Id - \gamma^0\otimes\gamma^0)$ as well as
the $U_A(1)$-invariant combination ${1/2}(\Id\otimes\Id -
\gamma^5\otimes\gamma^5 - \gamma^\mu\otimes\gamma_\mu)$, both providing a good
description of the ground state Regge trajectories up to highest observed
angular momenta. Whereas the first structure is slightly prefered concerning
numerous meson decay properties (see \cite{pap41}), we find the
$U_A(1)$-invariant force to be much more appropriate for the description of a
multitude of higher mass resonances discovered in the data of the {\sc Crystal
Barrel} collaboration during the last few years. Furthermore, this confinement
structure has the remarkable feature to yield a linear dependence of masses on
their radial excitation number. For many experimental resonances such a
trajectory-like behaviour was observed by Anisovich {\it et al.} We can confirm
that almost the same slope occurs for all trajectories. Adding the
$U_A(1)$-breaking instanton induced 't Hooft interaction we can compute the
pseudoscalar mass splittings with both Dirac structures and for the scalar
mesons a natural mechanism of flavour mixing is achieved. [...]

</DOC>
<DOC>
<DOCNO> 40605 </DOCNO>
Performances of the NA48 Liquid Krypton calorimeter


  The NA48 experiments aims at a precise measurement of direct CP violation in
the neutral Kaon system. This puts stringent requirements on the
electromagnetic calorimeter used to detect photons of average energy 25 GeV.
The choice of NA48 is a quasi homogeneous Liquid Krypton calorimeter with fast
readout. The operation of this device and the performances achieved are
described.

</DOC>
<DOC>
<DOCNO> 116583 </DOCNO>
Classical electromagnetism of r^2 spin-orbit interaction and


  We first obtain the electric and magnetic fields corresponding to a
`spin'-orbit classical interaction of a r^2 potential. Assuming that Maxwell
equations hold for these fields, we infer the conditions on the `spin' vector
forbidding magnetic monopoles

</DOC>
<DOC>
<DOCNO> 121301 </DOCNO>
Light Curves of GRB Optical Flashes


  The standard model of GRB afterglows assumes that relativistically expanding
material is decelerating due to interaction with the surrounding medium. The
afterglows are well described by the synchrotron radiation from a forward
shock, while the strong optical flash associated with GRB 990123 can be
attributed to the emission from a reverse shock. We give a detailed study on
the reverse shock emission. The full light curves are calculated for a long and
a short GRB cases. We discuss the lack of the prompt optical detections by
ROTSE for GRB 981121 and GRB 981223.

</DOC>
<DOC>
<DOCNO> 84865 </DOCNO>
Schwarzschild's Curved Spacetime Lagrangian with Its Quantum Equations


  From the curved spacetime Lagrangian the first approximation scalar particle
quantum equation was obtained following the canonical formalism. The roots of
this equation in Schwarzschild's pseudo flat space were found. As it was shown
in a more general curved spacetime it is tedious to find equation's roots. The
massless particle limiting case was considered. The Maxwell set of equations
generalized to Schwarzschild's space was reproduced.

</DOC>
<DOC>
<DOCNO> 12634 </DOCNO>
The frequency, temperature, and magnetic field dependence of


  Employing a broadband microwave reflection configuration, we have measured
the complex surface impedance, $Z_S(\omega,T,H)$, of single crystal
La$_{0.8}$Sr$_{0.2}$MnO$_3$, as a function of frequency (0.045-45 GHz),
temperature (250-325 K), and magnetic field (0-1.9 kOe). The microwave surface
impedance depends not only on the resistivity of the material, but also on the
magnetic permeability, $\hat\mu(\omega,T,H)$, which gives rise to ferromagnetic
resonance (FMR) and ferromagnetic anti-resonance (FMAR). The broadband nature
of this experiment allows us to follow the FMR to low frequency and to deduce
the behavior of both the local internal fields and the local magnetization in
the sample.

</DOC>
<DOC>
<DOCNO> 69256 </DOCNO>
Predictions for associated production of gauginos and gluinos at NLO in


  NLO SUSY-QCD contributions to associated production of gluinos and gauginos
are shown to enhance the cross sections by about 10% at the Tevatron and by as
much as a factor of two at the LHC. They shift the mass determinations or
discovery limits, soften the $p_T$ spectra, and stabilize the predictions
against variations of the renormalization and factorization scales.

</DOC>
<DOC>
<DOCNO> 84848 </DOCNO>
Analysis of Maxwell Equations in a Gravitational Field


  In a gravitational field, we analyze the Maxwell equations, the correponding
electromagnetic wave and continuity equations. A particular solution for
parellel electric and magnetic fields in a gravitational background is
presented. These solutions also satisfy the free-wave equations and the
phenomenology suggested by plasma physics.

</DOC>
<DOC>
<DOCNO> 122705 </DOCNO>
Measuring Cluster Temperature Profiles with XMM/EPIC


  Using the PV observation of A1795, we illustrate the capability of XMM-EPIC
to measure cluster temperature profiles, a key ingredient for the determination
of cluster mass profiles through the equation of hydrostatic equilibrium. We
develop a methodology for spatially resolved spectroscopy of extended sources,
adapted to XMM background and vignetting characteristics. The effect of the
particle induced background is discussed. A simple unbiased method is proposed
to correct for vignetting effects, in which every photon is weighted according
to its energy and location on the detector. We were able to derive the
temperature profile of A1795 up to 0.4 times the virial radius. A significant
and spatially resolved drop in temperature towards the center (r<200 kpc) is
observed, which corresponds to the cooling flow region of the cluster. Beyond
that region, the temperature is constant with no indication of a fall-off at
large radii out to 1.2 Mpc.

</DOC>
<DOC>
<DOCNO> 8583 </DOCNO>
Gap and pseudogap evolution within the charge-ordering scenario for


  We describe the spectral properties of underdoped cuprates as resulting from
a momentum-dependent pseudogap in the normal state spectrum. Such a model
accounts, within a BCS approach, for the doping dependence of the critical
temperature and for the two-parameter leading-edge shift observed in the
cuprates. By introducing a phenomenological temperature dependence of the
pseudogap, which finds a natural interpretation within the stripe
quantum-critical-point scenario for high-T_c superconductors, we reproduce also
the T_c-T^* bifurcation near optimum doping. Finally, we briefly discuss the
different role of the gap and the pseudogap in determining the spectral and
thermodynamical properties of the model at low temperatures.

</DOC>
<DOC>
<DOCNO> 169600 </DOCNO>
Approach to the semiconductor cavity QED in high-Q regimes with


  The high density Frenkel exciton which interacts with a single mode
microcavity field is dealed with in the framework of the q-deformed boson. It
is shown that the q-defomation of bosonic commutation relations is satisfied
naturally by the exciton operators when the low density limit is deviated. An
analytical expression of the physical spectrum for the exciton is given by
using of the dressed states of the cavity field and the exciton. We also give
the numerical study and compare the theoretical results with the experimental
results

</DOC>
<DOC>
<DOCNO> 40318 </DOCNO>
Recent results from SELEX


  Preliminary results on asymmetry for Lc produced by Sigma-,pi- and p beams at
xf>0.2 and precise measurements of the Lc,D0 and Ds lifetimes are presented.

</DOC>
<DOC>
<DOCNO> 122977 </DOCNO>
Diffuse Cluster-wide Radio Halos


  We will discuss the properties and origins of halos and relics including
estimates of the cluster magnetic fields, and present results for a few
recently discovered halos and relics. The electrons in the suprathermal high
energy tail of the thermal gas distribution are likely to provide the seed
particles for acceleration through mergers and turbulences to relativistic
energies. These relativistic particles are then responsible for the synchrotron
emission of the halos.

</DOC>
<DOC>
<DOCNO> 39801 </DOCNO>
Updated Global Analysis of the Atmospheric Neutrino Data in terms of


  A global analysis of all the available atmospheric neutrino data is presented
in terms of neutrino oscillations in the nu_mu -> nu_tau and nu_mu -> nu_s
channels, where nu_s denotes a sterile neutrino. We perform our analysis of the
contained events data as well as the upward-going neutrino-induced muon fluxes.
In addition to the previous data samples of Frejus, Nusex, IMB and Kamioka
experiments, we include the full data set of the 52 kton-yr of
Super-Kamiokande, the recent 4.6 kton-yr contained events of Soudan2 and the
results on upgoing muons from the MACRO and Baksan detectors. From the
statistical analysis it emerges that the nu_mu -> nu_tau channel provides the
best agreement with the combined data, with a best fit point of sin^2(2 theta)
= 0.99 and Delta m^2 = 3.0 * 10^{-3} eV^2. Although somehow disfavoured, the
nu_mu -> nu_s channels cannot be ruled out on the basis of the global fit to
the full set of observables.

</DOC>
<DOC>
<DOCNO> 178877 </DOCNO>
Odd-even mass differences in self-consistent Mean-Field calculations


  The odd-even mass staggering (OES) of nuclei is analyzed in the context of
self-consistent mean-field calculations. The procedure developed allows to
understand the OES for spherical as well as for deformed nuclei. Comparison
with results at the Hartree-Fock level shows the non-perturbative effect on
this observable of the inclusion of pairing correlations.

</DOC>
<DOC>
<DOCNO> 12346 </DOCNO>
Size effects on excitons in nano-rings


  The size effects of an exciton in a nano-ring are investigated theoretically
by using an effective-mass Hamiltonian which can be separated in terms of the
center-of-mass and relative coordinates. The binding energy and oscillator
strength of the ground state are calculated for two different ring radii as a
function of the ring width. The resulting linear optical susceptibility of the
low-lying exciton states is also discussed.

</DOC>
<DOC>
<DOCNO> 101493 </DOCNO>
Exponential separation in 4-manifolds


  We use a new geometric construction, grope splitting, to give a sharp bound
for separation of surfaces in 4-manifolds. We also describe applications of
this technique in link-homotopy theory, and to the problem of locating
pi_1-null surfaces in 4-manifolds. In our applications to link-homotopy, grope
splitting serves as a geometric substitute for the Milnor group.

</DOC>
<DOC>
<DOCNO> 120014 </DOCNO>
Construction of the one-point PDF of the local aperture mass in weak


  We present a general method for the reconstruction of the one-point
Probability Distribution Function of the local aperture mass in weak lensing
maps. Exact results, that neglect the lens-lens coupling and departure form the
Born approximation, are derived for both the quasilinear regime at leading
order and the strongly nonlinear regime assuming the tree hierarchical model is
valid. We describe in details the projection effects on the properties of the
PDF and the associated generating functions. In particular, we show how the
generic features which are common to both the quasilinear and nonlinear regimes
lead to two exponential tails for $P(\Map)$. We briefly investigate the
dependence of the PDF with cosmology and with the shape of the angular filter.
Our predictions are seen to agree reasonably well with the results of numerical
simulations and should be able to serve as foundations for alternative methods
to measure the cosmological parameters that take advantage of the full shape of
the PDF.

</DOC>
<DOC>
<DOCNO> 119483 </DOCNO>
Particle Heating by Nonlinear Alfvenic Turbulence in ADAFs


  Particle heating in advection-dominated accretion flows (ADAFs) by nonlinear
MHD (Alfvenic) turbulence is investigated. Such turbulence with
highly-fluctuating magnetic fields, $\tilde B\sim B_0$, is believed to be
naturally produced by the magnetic shearing instability near the nonlinear
saturation. It is shown that the energy is dissipated in the parallel cascade,
which occurs due to nonlinear compressibility of high-amplitude turbulence, and
predominantly heats protons, but not electrons. The conservative limit on the
electron--to--proton heating fraction is $\delta\lesssim{\rm
few}\times10^{-2}$.

</DOC>
<DOC>
<DOCNO> 84415 </DOCNO>
The Bianchi Type I minisuperspace model


  The minisuperspace model of a Bianchi Type I universe with compact spatial
sections is investigated. The classical solutions are brought onto a form were
the difference between compact and infinite spatial sections are manifest. One
of the features of the compact case is that it has a non-trivial moduli space.
The solution space of the compact Bianchi Type I universe is 10 dimensional
whereas the Kasner solutions only have a 1 dimensional solution space. We also
include the classical solutions with dust and a cosmological constant.
Solutions to the Wheeler-DeWitt equation are obtained in light of the tunneling
boundary proposal by Vilenkin. Backreaction effects from a simple scalar field
are also investigated.

</DOC>
<DOC>
<DOCNO> 122141 </DOCNO>
The M 31 double nucleus probed with OASIS and HST. A natural m=1 mode?


  We present observations with the adaptive optics assisted integral field
spectrograph OASIS of the M 31 double nucleus at a spatial resolution better
than 0.5 arcsec FWHM. These data are used to derive the two-dimensional stellar
kinematics within the central 2 arcsec. Archival WFPC2/HST images are revisited
to perform a photometric decomposition of the nuclear region. We also present
STIS/HST kinematics obtained from the archive. The luminosity distribution of
the central region is well separated into the respective contributions of the
bulge, the nucleus including P1 and P2, and the so-called UV peak. We then show
that the axis joining P1 and P2, the two local surface brightness maxima, does
not coincide with the kinematic major-axis, which is also the major-axis of the
nuclear isophotes (excluding P1). We also confirm that the velocity dispersion
peak is offset by ~ 0.2 arcsec from the UV peak, assumed to mark the location
of the supermassive black hole. The newly reduced STIS/HST velocity and
dispersion profiles are then compared to OASIS and other published kinematics.
We find significant offsets with previously published data. Simple parametric
models are then built to successfully reconcile all the available kinematics.
We finally interpret the observations using new N-body simulations. The nearly
keplerian nuclear disk of M31 is subject to a natural m=1 mode, with a very
slow pattern speed (3 km/s/pc for M_BH = 7 10^7~\Msun), that can be maintained
during more than a thousand dynamical times. The resulting morphology and
kinematics of the mode can reproduce the M~31 nuclear-disk photometry and mean
stellar velocity, including the observed asymmetries. It requires a central
mass concentration and a cold disk system representing between 20 and 40% of
its mass. Abridged..

</DOC>
<DOC>
<DOCNO> 119517 </DOCNO>
The Fe II problem in NLS1s


  For more than twenty years, strong Fe II emission lines have been observed in
Active Galactic Nuclei and in particular in Narrow Line Seyfert 1 galaxies. A
quick overview of the observations and of the models proposed to interpret the
Fe II spectrum is given. The influence of atomic data and of physical
parameters are discussed, and it is shown that the strengths of the Fe II lines
cannot be explained in the framework of photoionization models. A non-radiative
heating, for instance due to shocks, with an overabundance of iron, can help to
solve the problem. A comparison with other objects emitting intense Fe II lines
favors also the presence of strong outflows and shocks. We suggest some issues
in the context of AGN evolution.

</DOC>
<DOC>
<DOCNO> 70351 </DOCNO>
Anti-Kaon Induced Reactions on the Nucleon


  Using a previously established effective Lagrangian model we describe
anti-kaon induced reactions on the nucleon. The dominantly contributing
channels in the cm-energy region from threshold up to 1.72 GeV are included (K
N, \pi \Sigma, \pi \Lambda). We solve the Bethe-Salpeter equation in an unitary
$K$-matrix approximation.

</DOC>
<DOC>
<DOCNO> 69940 </DOCNO>
Low-Scale See-Saw Mechanisms for Light Neutrinos


  Alternatives to the see-saw mechanism are explored in supersymmetric models
with three right-handed or sterile neutrinos. Tree-level Yukawa couplings can
be drastically suppressed in a natural way to give sub-eV Dirac neutrino
masses. If, in addition, a B-L gauge symmetry broken at a large scale M_G is
introduced, a wider range of possibilities opens up. The value of the
right-handed neutrino mass M_R can be easily disentangled from that of M_G.
Dirac and Majorana neutrino masses at the eV scale can be generated radiatively
through the exchange of sneutrinos and neutralinos. Dirac masses m_D owe their
smallness to the pattern of light-heavy scales in the neutralino mass matrix.
The smallness of the Majorana masses m_L is linked to a similar see-saw pattern
in the sneutrino mass matrix. Two distinct scenarios emerge. In the first, with
very small or vanishing M_R, the physical neutrino eigenstates are, for each
generation, either two light Majorana states with mixing angle ranging from
very small to maximal, depending on the ratio m_D/M_R, or one light Dirac
state. In the second scenario, with a large value of M_R, the physical
eigenstates are two nearly unmixed Majorana states with masses \sim m_L and
\sim M_R. In both cases, the (B-L)-breaking scale M_G is, in general, much
smaller than that in the traditional see-saw mechanism.

</DOC>
<DOC>
<DOCNO> 122310 </DOCNO>
Chandra Observations of Variable Embedded X-ray sources in Orion. Paper


  We used the High Energy Transmission Grating Spectrometer (HETGS) onboard the
Chandra X-ray Observatory to perform two observations, separated by three
weeks, of the Orion Trapezium region. The zeroth order images on the Advanced
CCD Imaging Spectrometer (ACIS) provide spatial resolution of 0.5" and moderate
energy resolution. Within a 160"x140" region around the Orion Trapezium we
resolve 111 X-ray sources with luminosities between 7x10^{28} ergs/s and
2x10^{32} ergs/s. We do not detect any diffuse emission. Many sources appear
much more heavily absorbed, with N_H in the range of 10^22 to 10^23 cm^-2. The
main objective of this paper is to study the Orion Trapezium and its close
vicinity. Most spectra of the very early type members can be fit with a
two-temperature thermal spectrum with a soft component of kT ~ 0.8 keV and a
hard component of kT ~ 2 to 3 keV. We discuss these results in the context of
stellar wind models. We detect eight additional, mostly variable X-ray sources
in the close vicinity of the Trapezium. Five of these X-rays sources are
identified with proplyds and we argue that the X-ray emission originates from
class I, II and III protostars at the cores of the proplyds.

</DOC>
<DOC>
<DOCNO> 12660 </DOCNO>
Colossal Magnetoresistance using the Small Polaron Picture with Finite


  We present a small polaron picture and show that finite bandwidth effects are
important to understand colossal magnetoresistance. Besides the polaron size
parameter, we show that there is another parameter (adiabaticity parameter)
that is relevant to studying magnetoresistance. We find that for fixed values
of the polaron size parameter an increase in the adiabaticity parameter
increases the magnetoresistance. The magnetic transition is studied within a
mean field approach. We point out important oversights in the literature. We
find that for the reported values of the bandwidth (based on band structure
calculations) and for experimentally determined values of activation energy and
Debye frequency, the calculated values of the magnetoresistance compare
favorably with experimental ones. We calculate the optical conductivity too and
find that there is reasonable agreement with experiment.

</DOC>
<DOC>
<DOCNO> 123001 </DOCNO>
A Multivariate Analysis of Galaxies in the Hubble Deep Field North


  We use the ultraviolet and optical WFPC2 and near-infrared NICMOS images of
the Hubble Deep Field North to measure and statistically compare an array of
parameters for over 250 of the galaxies it contains. These parameters include
redshift, rest-frame visible asymmetry and concentration, bolometric luminosity
and extinction-corrected star formation rate. We find only one strong
correlation, between bolometric luminosity and star formation rate, from which
early-type galaxies noticeably deviate. When our asymmetry measurements are
combined with those of a sample of nearby galaxies covering the full Hubble
sequence, we find a weak correlation between redshift and rest-frame visible
asymmetry, consistent with the qualitative evidence of galaxy morphological
evolution from these and other deep Hubble Space Telescope images. The mean
values of these asymmetry measurements show a monotonic increase with redshift
interval over the range 0 < z < 2, increasing by a factor of approximately
three. If this trend is real, it suggests that galaxy morphological evolution
is a gradual process that is continuing through the present cosmological epoch.
There is evidence that the dominant source of this evolution is the "minor"
mergers of disk galaxies with smaller companions, which could also transform
late-type spiral galaxies into early-type spiral galaxies. Interestingly, in
contrast to local galaxies we find no correlations between star formation rate
and either UV or visible asymmetry. This could arise if the star formation of
high-redshift galaxies proceeds in episodes that are short (~ 100 Myr) relative
to the time scales over which galaxy mergers produce strong asymmetries (~ 500
Myr), a result suggested by the high star formation rates of Lyman break
galaxies.

</DOC>
<DOC>
<DOCNO> 151012 </DOCNO>
Target Space Pseudoduality Between Dual Symmetric Spaces


  A set of on shell duality equations is proposed that leads to a map between
strings moving on symmetric spaces with opposite curvatures. The transformation
maps "waves" on a riemannian symmetric space to "waves" on its dual riemannian
symmetric space. This transformation preserves the energy momentum tensor
though it is not a canonical transformation. The preservation of the energy
momentum tensor has a natural geometrical interpretation. The transformation
maps "particle-like solutions" into static "soliton-like solutions". The
results presented here generalize earlier results of E. Ivanov.

</DOC>
<DOC>
<DOCNO> 69507 </DOCNO>
Gluonic Correlations in Matter


  We derive the analogue of the QCD low energy theorems for the scalar and
pseudoscalar gluonic correlators in nuclear matter. We find that the scalar
correlations are depleted while the pseudoscalar correlations are enhanced to
leading order in the nuclear matter density. We briefly discuss the
consequences of these findings on the QCD spectrum.

</DOC>
<DOC>
<DOCNO> 100399 </DOCNO>
The action of the Frobenius map on rank 2 vector bundles in


  Let $X$ be an ordinary smooth curve defined over an algebraically closed
field of characteristic 2. The absolute Frobenius induces a rational map $F$ on
the moduli space $M_X$ of rank 2 vector bundles with fixed trivial determinant.
If the genus of $X$ is 2, the moduli space $M_X$ is isomorphic to projective
space of dimension 3 (as over the complex numbers). In this case we explicitly
give the equations of $F$, which enables us to determine, for example, its base
locus (one point) and its image (different from $M_X$).

</DOC>
<DOC>
<DOCNO> 118971 </DOCNO>
Background discrimination capabilities of a heat and ionization


  The discrimination capabilities of a 70 g heat and ionization Ge bolometer
are studied. This first prototype has been used by the EDELWEISS Dark Matter
experiment, installed in the Laboratoire Souterrain de Modane, for direct
detection of WIMPs. Gamma and neutron calibrations demonstrate that this type
of detector is able to reject more than 99.6% of the background while retaining
95% of the signal, provided that the background events distribution is not
biased towards the surface of the Ge crystal. However, the 1.17 kg.day of data
taken in a relatively important radioactive environment show an extra
population slightly overlapping the signal. This background is likely due to
interactions of low energy photons or electrons near the surface of the
crystal, and is somewhat reduced by applying a higher charge-collecting inverse
bias voltage (-6 V instead of -2 V) to the Ge diode. Despite this
contamination, more than 98% of the background can be rejected while retaining
50% of the signal. This yields a conservative upper limit of 0.7
event.day^{-1}.kg^{-1}.keV^{-1}_{recoil} at 90% confidence level in the 15-45
keV recoil energy interval; the present sensitivity appears to be limited by
the fast ambient neutrons. Upgrades in progress on the installation are
summarized.

</DOC>
<DOC>
<DOCNO> 71233 </DOCNO>
Vector Manifestation of the Chiral Symmetry


  We propose ``vector manifestation (VM)'' of the Wigner realization of the
chiral symmetry in which the symmetry is restored at the critical point by the
massless degenerate pion (and its flavor partners) and rho meson (and its
flavor partners) as the chiral partner, in sharp contrast to the traditional
manifestation \'a la linear sigma model where the symmetry is restored by the
degenerate pion and scalar meson. The application to the chiral phase
transition of the large Nf QCD is performed using the hidden local symmetry
Lagrangian. Combined with the Wilsonian matching proposed recently, the VM
determines the critical number of massless flavors Nf \simeq 5 without much
ambiguity.

</DOC>
<DOC>
<DOCNO> 101974 </DOCNO>
Dual Entropy in Discrete Groups with Amenable Actions


  We introduce a notion of entropy for automorphisms of discrete groups which
admit amenable actions on a compact space. This entropy is dual to classical
topological entropy in the sense that if G is discrete and abelian then our
notion of entropy agrees with the topological entropy of the induced
automorphism on the (compact) dual group of G.
  We prove a number of basic properties of this dual entropy and give a few
calculations. In particular, we are able to give precise calculations for
arbitrary automorphisms of crystallographic groups.

</DOC>
<DOC>
<DOCNO> 68035 </DOCNO>
Mirror Neutrinos and the Early Universe


  I review the construction of the Exact Parity or Mirror Matter Model and
explain how it solves the solar and atmospheric neutrino problems. The
oscillation driven relic neutrino asymmetry amplification phenomenon is then
used to demonstrate the consistency of the model with Big Bang Nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 170103 </DOCNO>
Wavelets as basis functions in canonical quantization


  Canonical quantization of electromagnetic field is traditionally done using
plane waves. It is possible to formulate the quantization using other complete
set of basis functions. Wavelets are a special kind of functions which are
localized in real as well as in Fourier space. In this paper we show how
wavelets can be used as basis functions in canonical quantization. A countable
set of mode functions are obtained. The general formalism of the change of
basis is the same for all wavelets which satisfy a multiresolution analysis.

</DOC>
<DOC>
<DOCNO> 119125 </DOCNO>
Ferromagnetism of quark liquid and magnetars


  Spontaneous magnetization of quark liquid is examined on the analogy with
that in electron gas. It is pointed out that quark liquid has potential to be
ferromagnetic at rather low densities, around nuclear saturation density. Somme
comments are given as for implications on magnetars.

</DOC>
<DOC>
<DOCNO> 10618 </DOCNO>
Higher Derivative CP(N) Model and Quantization of the Induced


  We consider higher derivative CP(N) model in 2+1 dimensions with the
Wess-Zumino-Witten term and the topological current density squared term. We
quantize the theory by using the auxiliary gauge field formulation in the path
integral method and prove that the extended model remains renormalizable in the
large N limit. We find that the Maxwell-Chern-Simons theory is dynamically
induced in the large N effective action at a nontrivial UV fixed point. The
quantization of the Chern-Simons term is also discussed.

</DOC>
<DOC>
<DOCNO> 119763 </DOCNO>
The Solar Core and Solar Neutrinos


  The long-standing deficit of measured versus predicted solar neutrino fluxes
is re-examined in light of possible astrophysical solutions. In the last
decade, solar neutrino flux and helioseismic measurements have greatly
strengthened the case for non-astrophysical solutions. But some model-
independent tests remain open.

</DOC>
<DOC>
<DOCNO> 116636 </DOCNO>
Photon findings


  Two experiments were made using a microwave generator, which sent a narrow
beam, through a metallic plate with horizontal movement. At the other end a
horn antenna coupled to a field-strength detector. In linear polarization
double cycloids paths were found and in circular polarization spiral paths were
found. These experiments suggested that the photon is composed by two particles
in dynamic equilibrium. The description of this model is given later as well as
its parameters.

</DOC>
<DOC>
<DOCNO> 102218 </DOCNO>
Conditional expectations on compact quantum groups and new examples of


  We propose a construction of quantum hypergroups using conditional
expectations on compact quantum groups. Using this construction, we describe
several series of non-trivial finite-dimensional quantum hypergroups via
conditional expectations of Delsart type on non-trivial Kac algebras obtained
by twisting of the finite groups.

</DOC>
<DOC>
<DOCNO> 69392 </DOCNO>
The on-shell massless planar double box diagram with an irreducible


  Using a Mellin-Barnes representation, we compute the on-shell massless planar
double box Feynman diagram with an irreducible scalar product of loop momenta
in the numerator. This diagram is needed in calculations of two loop
corrections to scattering processes of massless particles, together with the
double box without numerator calculated previously by Smirnov. We verify the
poles in epsilon of our result by means of a system of differential equations
relating the two diagrams, which we present in an explicit form. We verify the
finite part with an independent numerical check.

</DOC>
<DOC>
<DOCNO> 71862 </DOCNO>
Threshold Resummation and Rapidity Dependence


  We study the effects of threshold resummation on the rapidity dependence of
single-particle-inclusive cross sections, using the prompt photon cross section
as an example. We make use of the full resummation formula at next-to-leading
logarithmic accuracy and develop a new technique for treating rapidity in
resummation. We compare our phenomenological results with those of previous
studies and discuss differences and similarities of the two existing
resummation formalisms.

</DOC>
<DOC>
<DOCNO> 11887 </DOCNO>
The Edge-State Theory of Integer-Quantum-Hall-Effect to Insulator


  Direct transitions, driven by disorder, from several integral quantum Hall
states to an insulator have been observed in experiment. This finding is
enigmatic in light of a theoretical phase diagram, based on rather general
considerations, that predicts a sequence of transitions in which the integer
$n$ characterizing the Hall conductivity is reduced successively by unity,
eventually going from $n=1$ into an insulator. In this work, we suggest that
the direct transition occurs because, in certain parameter regime, the edge
states of different Landau levels are strongly coupled and behave as a single
edge state. It is indicated under what conditions successive transitions may be
seen.

</DOC>
<DOC>
<DOCNO> 71959 </DOCNO>
QCD prediction for heavy boson transverse momentum distributions


  We investigate the predictive power of Collins, Soper, and Sterman's
$b$-space QCD resummation formalism for transverse momentum ($Q_T$)
distributions of heavy boson production in hadronic collisions. We show that
the predictive power of the resummation formalism has a strong dependence on
the collision energy $\sqrt{S}$ in addition to its well-known $Q^2$ dependence,
and the $\sqrt{S}$ dependence improves the predictive power at collider
energies. We demonstrate that at Tevatron and the LHC energies, the $Q_T$
distributions derived from $b$-space resummation are not sensitive to the
nonperturbative input at large $b$, and give good descriptions of the $Q_T$
distributions of heavy boson production at all transverse momenta $Q_T \leq Q$.

</DOC>
<DOC>
<DOCNO> 70621 </DOCNO>
False Vacuum Black Holes and Universes


  We construct a black hole whose interior is the false vacuum and whose
exterior is the true vacuum of a classical field theory. From the outside the
metric is the usual Schwarzschild one, but from the inside the space is de
Sitter with a cosmological constant determined by the energy of the false
vacuum. The parameters of the field potential may allow for the false vacuum to
exist for more than the present age of the universe. A potentially relevant
effective field theory within the context of QCD results in a Schwarzschild
radius of about 200 km.

</DOC>
<DOC>
<DOCNO> 13313 </DOCNO>
Erratum: Is it possible to infer the equation of state of a mixture of


  The numerical values in the sixth and seventh columns of table 1 of the paper
Molec. Phys., 1999, 96, 1185-1188 are not correct. Consequently, some of the
comments made in the paper are wrong. The corrected version of table 1 is
reprinted here and the results are briefly discussed.

</DOC>
<DOC>
<DOCNO> 117714 </DOCNO>
Properties of disk galaxies in a hierarchical formation scenario


  We used galaxy evolutionary models in a hierarchical inside-out formation
scenario to study the origin of the main properties and correlations of disk
galaxies. We found that most of these properties and correlations are the
result of three (cosmological) initial factors and their dispersions: the
virial mass, the halo mass aggregation history (MAH), and the angular momentum
given through the spin parameter \lambda. The MAH determines mainly the halo
structure and the color indexes while \lambda determines mainly the surface
brightness and the bulge-to-disk ratio. We calculated star formation (SF) using
a gravitational instability criterion and a self-regulation mechanism in the
turbulent ISM. The efficiency of SF in this model is almost independent from
the mass. We show that the luminosity-dependent dust absorption empirically
determined by Wang & Heckman explains the observed color-magnitude and color
Tully-Fisher (TF) relations without the necessity of introducing a
mass-dependent SF efficiency. The disks in centrifugal equilibrium form within
growing CDM halos with a gas accretion rate proportional to the MAH. The disks
present exponential surface density and brightness profiles, negative radial
color index gradients, and nearly flat rotation curves. We also calculated the
secular formation of a bulge due to gravitational instabilities in the stellar
disk. The intensive properties of our models agree with the observational data
and the trends of the Hubble sequence are reproduced. The predicted infrared TF
and luminosity-radius relations also agree with observations. The main
shortcomings of our inside-out hierarchical models are the excessive radial
color gradients and the dark halo dominion in the rotation curve
decompositions.

</DOC>
<DOC>
<DOCNO> 120006 </DOCNO>
Serendipitous 2MASS Discoveries Near the Galactic Plane: A Spiral Galaxy


  We present the basic properties of three objects near the Galactic Plane - a
large galaxy and two candidate globular clusters - discovered in the Two Micron
All Sky Survey (2MASS) dataset. All were noted during spot-checks of the data
during 2MASS quality assurance reviews. The galaxy is a late-type spiral galaxy
(Sc-Sd), ~11 Mpc distant. We estimate an extinction-corrected optical diameter
of ~9.5', making it larger than most Messier galaxies. The candidate globular
clusters are ~2-3' in extent and are hidden optically behind foreground
extinctions of Av ~18-21 mag at l ~ 10 deg, b ~ 0 deg. These chance discoveries
were not the result of any kind of systematic search but they do hint at the
wealth of obscured sources of all kinds, many previously unknown, that are in
the 2MASS dataset.

</DOC>
<DOC>
<DOCNO> 68997 </DOCNO>
The Infrared Behavior of QCD Propagators in Landau Gauge


  Some features of the solutions to the truncated Dyson-Schwinger
equations(DSEs) for the propagators of QCD in Landau gauge are summarized. In
particular, the Kugo-Ojima confinement criterion is realized, and positivity of
transverse gluons is manifestly violated in these solutions. In Landau gauge,
the gluon-ghost vertex function offers a convenient possibility to define a
nonperturbative running coupling. The infrared fixed point obtained from this
coupling which determines the 2-point interactions of color-octet quark
currents implies the existence of unphysical massless states which are
necessary to escape the cluster decomposition of colored clusters. The gluon
and ghost propagators, and the nonperturbative running coupling, are compared
to recent lattice simulations. A significant deviation of the running coupling
from the infrared behavior extracted in simulations of 3-point functions is
attributed to an inconsistency of asymmetric subtraction schemes due to a
consequence of the Kugo-Ojima criterion: infrared enhanced ghosts.

</DOC>
<DOC>
<DOCNO> 116769 </DOCNO>
Further Studies on the Prospects for Many-TeV Muon Colliders


  New self-consistent parameter sets are presented and discussed for muon
collider rings at center-of-mass energies of 10, 30 and 100 TeV. All three
parameter sets attain luminosities of 3 x 10^35 /cm^2/s. The parameter sets
benefit from new insights gained at the HEMC'99 workshop that considered the
feasibility of many-TeV muon colliders.

</DOC>
<DOC>
<DOCNO> 83363 </DOCNO>
Japanese Probabilistic Information Retrieval Using Location and Category


  Robertson's 2-poisson information retrieve model does not use location and
category information. We constructed a framework using location and category
information in a 2-poisson model. We submitted two systems based on this
framework to the IREX contest, Japanese language information retrieval contest
held in Japan in 1999. For precision in the A-judgement measure they scored
0.4926 and 0.4827, the highest values among the 15 teams and 22 systems that
participated in the IREX contest. We describe our systems and the comparative
experiments done when various parameters were changed. These experiments
confirmed the effectiveness of using location and category information.

</DOC>
<DOC>
<DOCNO> 101143 </DOCNO>
Miyanishi's characterization of the affine 3-space does not hold in


  We present an example which confirms the assertion of the title.

</DOC>
<DOC>
<DOCNO> 101648 </DOCNO>
Unlinked Embedded Graphs


  This paper is a self-contained development of an invariant of graphs embedded
in three-dimensional Euclidean space using the Jones polynomial and skein
theory. Some examples of the invariant are computed. An unlinked embedded graph
is one that contains only trivial knots or links. Examples show that the
invariant is sufficiently powerful to distinguish some different unlinked
embeddings of the same graph.

</DOC>
<DOC>
<DOCNO> 170191 </DOCNO>
Stochastic mechanics and the Feynman integral


  The Feynman integral is given a stochastic interpretation in the framework of
Nelson's stochastic mechanics employing a time-symmetric variant of Nelson's
kinematics recently developed by the author.

</DOC>
<DOC>
<DOCNO> 152144 </DOCNO>
On properties of the asymptotic expansion of the heat trace for the N/D


  The spectral problem where the field satisfies Dirichlet conditions on one
part of the boundary of the relevant domain and Neumann on the remainder is
discussed. It is shown that there does not exist a classical asymptotic
expansion for short time in terms of fractional powers of $t$ with locally
computable coefficients.

</DOC>
<DOC>
<DOCNO> 39809 </DOCNO>
Energy Losses of Q-balls


  After a short review of Q-balls properties, in this paper we discuss their
interaction with matter, and their energy losses in the earth, for a large
range of velocities. These calculations are used to compute the fractional
angular acceptance of a detector located at Gran Sasso Laboratory. Furthermore
we computed the light yield in liquid scintillators, the ionization in streamer
tubes and the Restricted Energy Loss in the CR39 nuclear track detector.

</DOC>
<DOC>
<DOCNO> 123036 </DOCNO>
Subparsec-scale HI in the nucleus of NGC 4151


  We present sensitive, high-resolution 21-cm VLBA+VLA observations of the
radio jet and nuclear HI absorption in NGC 4151. The 25-mas (1.6-pc) resolution
continuum image reveals a highly collimated radio jet, underlying the discrete
components seen previously with MERLIN and the VLA. Spatially and kinematically
complex HI absorption is detected against the whole 3-pc extent of the
continuum component predicted by Ulvestad et al. to contain the AGN. Instead,
we suggest the component against which the absorption is detected is part of
the eastern counterjet, ruling it out as the location for the AGN.

</DOC>
<DOC>
<DOCNO> 70248 </DOCNO>
Precise calculation of the Casimir force between gold surfaces


  We analyse the result of precise measurement of the Casimir force between
bodies covered with gold. The values of the parameters used to extrapolate the
gold dielectric function to low frequencies are very important and discussed in
detail. The finite temperature effect is shown to exceed considerably the
experimental errors. The upper limit on the force is found which is smaller
than the measured force. Many experimental and theoretical uncertainties were
excluded with gold covering and we conclude that, possibly, a new force has
been detected at small separations between bodies.

</DOC>
<DOC>
<DOCNO> 13256 </DOCNO>
Causality is an effect


  Using symmetric boundary conditions at separated times, I show analytically
that both the time ordering of (macroscopic) causality and the direction of
entropy increase follow from these boundary conditions. In particular, when the
endpoints have low entropy, these arrows of time point away from the ends and
toward the middle. Causality in this context means that when perturbations are
applied, the effect of the perturbation---the macroscopic change in the
system's behavior---is confined to one temporal side of the perturbations.
These results hold for both mixing and integrable systems, although relaxation
for integrable systems is incomplete. Simulations are presented for purposes of
illustration.

</DOC>
<DOC>
<DOCNO> 13677 </DOCNO>
Nonuniversal Effects in the Homogeneous Bose Gas


  Effective field theory predicts that the leading nonuniversal effects in the
homogeneous Bose gas arise from the effective range for S-wave scattering and
from an effective three-body contact interaction. We calculate the leading
nonuniversal contributions to the energy density and condensate fraction and
compare the predictions with results from diffusion Monte Carlo calculations by
Giorgini, Boronat, and Casulleras. We give a crude determination of the
strength of the three-body contact interaction for various model potentials.
Accurate determinations could be obtained from diffusion Monte Carlo
calculations of the energy density with higher statistics.

</DOC>
<DOC>
<DOCNO> 150808 </DOCNO>
Effective Action of Matter Fields in Four-Dimensional String


  We study various aspects of the Kahler metric for matter fields in N=1,2
orientifold compactifications of type IIB string theory. The result has an
infrared-divergent part which reproduces the field- theoretical anomalous
dimensions, and a moduli-dependent part which comes from N=2 sectors of the
orientifold. For the N=2 orientifolds, we also compute the disk amplitude for
two matter fields on the boundary and a twisted closed string modulus in the
bulk. Our results are in agreement with supersymmetry: the singlet under the
SU(2)_R R-symmetry has vanishing coupling, while the coupling of the SU(2)_R
triplet does not vanish.

</DOC>
<DOC>
<DOCNO> 69385 </DOCNO>
Weak Scale in Heterotic String


  We investigate the possibility of lowering the string scale in four
dimensional heterotic models possessing a non-perturbative extension of the
gauge group. In particular, we consider a class of compactifications in which
the perturbative gauge sector is massive, and all the gauge bosons are
non-perturbative, with a coupling independent on the Planck and string scales.

</DOC>
<DOC>
<DOCNO> 119829 </DOCNO>
A Powerful Radio Halo in the Hottest Known Cluster of Galaxies 1E0657-56


  We report the detection of a diffuse radio halo source in the hottest known
cluster of galaxies 1E0657-56 (RXJ0658-5557). The radio halo has a morphology
similar to the X-ray emission from the hot intracluster medium. The presence of
a luminous radio halo in such a hot cluster is further evidence for a steep
correlation between the radio halo power and the X-ray temperature. We favour
models for the origin of radio halo sources involving a direct connection
between the X-ray emitting thermal particles and the radio emitting
relativistic particles.

</DOC>
<DOC>
<DOCNO> 13901 </DOCNO>
Comment on "Orbitally degenerate spin-1 model for insulating V2O3"


  We criticize the model proposed by Mila et al. (Phys.Rev.Lett. 85 (2000)
1714) for the description of the V3+ ion in V2O3 by pointing out that it is
completely artificial because the condition about the degenerate (doublet)
orbital ground state required for the authors' model cannot be realized in the
reality. We claim that the V3+ ion should be considered as described by the
quantum numbers S=1 and L=3 and with taking into account the orbital moment and
the intra-atomic spin-orbit coupling. PACS: 71.70.E, 75.10.D

</DOC>
<DOC>
<DOCNO> 70374 </DOCNO>
Topological and confining properties of Abelian-projected SU(3)-QCD


  In this talk, we discuss several topics related to the Abelian-projected
SU(3)-QCD. First of them is the Aharonov-Bohm effect emerging during the
extension of this theory by the introduction of the $\Theta$-term. Another
topic is devoted to various consequences of screening of the dual vector bosons
by electric vortex loops. In particular, it is demonstrated that this effect
modifies significantly the interaction of quarks. Next, the influence of
screening to electric and magnetic field correlators in the four-dimensional
Abelian-projected SU(3)-QCD is studied. Finally, the bilocal correlator of
electric field strengths in the three-dimensional gas of SU(3)
Abelian-projected monopoles is discussed.

</DOC>
<DOC>
<DOCNO> 169828 </DOCNO>
Quantum communication between atomic ensembles using coherent light


  Protocols for quantum communication between massive particles, such as atoms,
are usually based on transmitting nonclassical light, and/or super-high finesse
optical cavities are normally needed to enhance interaction between atoms and
photons. We demonstrate a surprising result: an unknown quantum state can be
teleported from one free-space atomic ensemble to the other by transmitting
only coherent light. No non-classical light and no cavities are needed in the
scheme, which greatly simplifies its experimental implementation.

</DOC>
<DOC>
<DOCNO> 120525 </DOCNO>
Stellar contributors to the hard X-ray background?


  We use simple energetic arguments to estimate the contribution of massive
X-ray binaries and supernova remnants to the cosmic X-ray background (XRB) at
energies in excess of 2 keV. Recent surveys have shown that AGN probably
account for most of the hard XRB (E > 2 keV), but there have been many
suggestions that star-forming galaxies could emerge at fainter fluxes and
perhaps account for a significant fraction of the soft and hard X-ray energy
density. Assuming that the formation rate of massive X-ray binaries (MXRBs)
traces the global star-formation rate, we find that their integrated
contribution to the hard XRB can be estimated and is shown to be small (at less
than the 1% level). Similarly, the integrated flux of SN is also shown to be
insignificant, or at most comparable to MXRBs. AGN therefore remain the most
viable candidates for producing the hard XRB, unless additional processes can
be shown to dominate the global hard X-ray emission in distant starburst
galaxies.

</DOC>
<DOC>
<DOCNO> 85610 </DOCNO>
Dual Metrics for a Class of Radiative Spacetimes


  Second rank non-degenerate Killing tensors for some subclasses of spacetimes
admitting parallel null one-planes are investigated. Lichn\'erowicz radiation
conditions are imposed to provide a physical meaning to spacetimes whose
metrics are described through their associated second rank Killing tensors.
Conditions under which the dual spacetimes retain the same physical properties
are presented.

</DOC>
<DOC>
<DOCNO> 11196 </DOCNO>
Robust chaos generation by a perceptron


  The properties of time series generated by a perceptron with monotonic and
non-monotonic transfer function, where the next input vector is determined from
past output values, are examined. Analysis of the parameter space reveals the
following main finding: a perceptron with a monotonic function can produce
fragile chaos only whereas a non-monotonic function can generate robust chaos
as well. For non-monotonic functions, the dimension of the attractor can be
controlled monotonically by tuning a natural parameter in the model.

</DOC>
<DOC>
<DOCNO> 84403 </DOCNO>
Towards a Stable Numerical Evolution of Strongly Gravitating Systems in


  We study the stability of three-dimensional numerical evolutions of the
Einstein equations, comparing the standard ADM formulation to variations on a
family of formulations that separate out the conformal and traceless parts of
the system. We develop an implementation of the conformal-traceless (CT)
approach that has improved stability properties in evolving weak and strong
gravitational fields, and for both vacuum and spacetimes with active coupling
to matter sources. Cases studied include weak and strong gravitational wave
packets, black holes, boson stars and neutron stars. We show under what
conditions the CT approach gives better results in 3D numerical evolutions
compared to the ADM formulation. In particular, we show that our implementation
of the CT approach gives more long term stable evolutions than ADM in all the
cases studied, but is less accurate in the short term for the range of
resolutions used in our 3D simulations.

</DOC>
<DOC>
<DOCNO> 116761 </DOCNO>
Design Studies for a High Current Bunching System for CLIC Test Facility


  A bunching system is proposed for the initial stage of CTF3 which consists of
one (two) 3 GHz prebunchers and one 3 GHz travelling wave (TW) buncher with
variable phase velocities. The electron beam is emitted from a 140 KV DC gun.
Since the macropulse beam current (3.5 A) at the exit of the TW buncher is
rather high, inside the TW buncher one has to take the beam loading effect into
consideration. By using PARMELA, it is shown numerically that the bunching
system can provide the bunches whose properties satisfy the design requirement
of CTF3. The 0.8 m long TW buncher working at 2pi/3 mode has two phase
velocities, 0.75 and 1. The dimensions of the caities in the two phase velocity
regions are proposed considering the beam loading effect. The transient beam
loading effect and the multibunch transverse instabilities are studied
numerically, and it is concluded that higher order mode couplers should be
installed in the TW buncher with the loaded quality factor of the dipole mode
lower than 80.

</DOC>
<DOC>
<DOCNO> 150463 </DOCNO>
A Renormalization Group Study of the $(\phi^* \phi)^3$ Model coupled to


  We consider the model of a massless charged scalar field, in (2+1)
dimensions, with a self interaction of the form $lambda (\phi^* \phi)^3$ and
interacting with a Chern Simons field. We calculate the renormalization group
$\beta$ functions of the coupling constants and the anomalous dimensions
$\gamma$ of the basic fields. We show that the interaction with the Chern
Simons field implies in a $\beta_{\lambda}$ which suggests that a dynamical
symmetry breakdown occurs. We also study the effect of the Chern Simons field
on the anomalous dimensions of the composite operators $(\phi^* \phi)^n$,
getting the result that their operator dimensions are lowered.

</DOC>
<DOC>
<DOCNO> 101758 </DOCNO>
On the concentration of eigenvalues of random symmetric matrices


  We prove that few largest (and most important) eigenvalues of random
symmetric matrices of various kinds are very strongly concentrated. This strong
concentration enables us to compute the means of these eigenvalues with high
precision. Our approach uses Talagrand's inequality and is very different from
standard approaches.

</DOC>
<DOC>
<DOCNO> 117341 </DOCNO>
Transparent Anomalous Dispersion and Superluminal Light Pulse


  Anomalous dispersion cannot occur in a transparent passive medium where
electromagnetic radiation is being absorbed at all frequencies, as pointed out
by Landau and Lifshitz. Here we show, both theoretically and experimentally,
that transparent linear anomalous dispersion can occur when a gain doublet is
present. Therefore, a superluminal light pulse propagation can be observed even
at a negative group velocity through a transparent medium with almost no pulse
distortion. Consequently, a {\it negative transit time} is experimentally
observed resulting in the peak of the incident light pulse to exit the medium
even before entering it. This counterintuitive effect is a direct result of the
{\it rephasing} process owing to the wave nature of light and is not at odds
with either causality or Einstein's theory of special relativity.

</DOC>
<DOC>
<DOCNO> 116763 </DOCNO>
Double resonance frequency shift in a hydrogen maser


  We use the dressed atom formalism to calculate the frequency shift in a
hydrogen maser induced by applied radiation near the Zeeman frequency, and find
excellent agreement with a previous calculation made in the bare atom basis.
The maser oscillates on the Delta_F = 1, Delta_m_F = 0 hyperfine transition,
while the applied field is swept through the F = 1, Delta_m_F = \pm 1 Zeeman
resonance. We determine the effect of the applied field on the Zeeman levels
using the dressed atom picture, and then calculate the maser frequency shift by
coupling the dressed states to the microwave cavity. Qualitatively, the
dressed-atom analysis gives a new and simpler physical interpretation of this
double resonance process, which has applications in precision hydrogen Zeeman
spectroscopy, e.g., in fundamental symmetry tests.

</DOC>
<DOC>
<DOCNO> 118323 </DOCNO>
Modelling galaxy clustering at high redshift


  Most phenomenological galaxy formation models show a discrepancy between the
predicted Tully-Fisher relation and the luminosity function. We show that this
is mainly due to overmerging of galaxy haloes, which is inherent in both the
Press-Schechter formalism and dissipationless N-body simulations. This
overmerging problem be circumvented by including a specific galaxy halo
formation recipe into an otherwise standard N-body code. Resolving the
overmerging also allows us to include models for chemical evolution and
starbursts, which improves the match to observational data and renders the
modelling more realistic. We use high-redshift clustering data to try and
distinguish models which predict similar results at low redshifts for different
sets of parameters.

</DOC>
<DOC>
<DOCNO> 13466 </DOCNO>
Multi-mode description of an interacting Bose-Einstein condensate


  We study the equilibrium dynamics of a weakly interacting Bose-Einstein
condensate trapped in a box. In our approach we use a semiclassical
approximation similar to the description of a multi-mode laser. In dynamical
equations derived from a full N-body quantum Hamiltonian we substitute all
creation (and annihilation) operators (of a particle in a given box state) by
appropriate c-number amplitudes. The set of nonlinear equations obtained in
this way is solved numerically. We show that on the time scale of a few
miliseconds the system exhibits relaxation - reaches an equilibrium with
populations of different eigenstates fluctuating around their mean values.

</DOC>
<DOC>
<DOCNO> 13001 </DOCNO>
Spinons and holons on the lattice


  We point out that the dynamical fermion mass generation in the 3D compact
U(1) lattice gauge theory with charged fermion and scalar fields (chi-U-phi_3
model) may be of relevance for the spinon-holon theory with local gauge
symmetry in the condensed matter physics. However, many properties of the model
are uncertain, so we make some conjectures to motivate their future
investigation. Most probably, for strong gauge coupling the model is by
universality equivalent to the familiar 3D four-fermion coupling models with
N_f=2. Available numerical results indicate that at the intermediate and weak
gauge coupling two universality classes with new interesting physics may arise.
One of them is associated with a tricritical point which probably exists in the
phase diagram of the model. The other one is determined by the dynamical
fermion mass generation in the compact QED_3, which is insufficiently
understood but of much interest by itself.

</DOC>
<DOC>
<DOCNO> 101286 </DOCNO>
Bounds for Betti numbers


  In this paper we prove parts of a conjecture of Herzog giving lower bounds on
the rank of the free modules appearing in the linear strand of a graded $k$-th
syzygy module over the polynomial ring. If in addition the module is
$\mathbb{Z}^n$-graded we show that the conjecture holds in full generality.
Furthermore, we give lower and upper bounds for the graded Betti numbers of
graded ideals with a linear resolution and a fixed number of generators.

</DOC>
<DOC>
<DOCNO> 11736 </DOCNO>
One-parameter superscaling in three dimensions


  Numerical and analytical details are presented on the newly discovered
superscaling property of the energy spacing distribution in the three
dimensional Anderson model.

</DOC>
<DOC>
<DOCNO> 71958 </DOCNO>
Is nonperturbative inflatino production during preheating a real threat


  We discuss toy models where supersymmetry is broken due to non-vanishing
time-varying vacuum expectation value of the inflaton field during preheating.
We discuss the production of inflatino the superpartner of inflaton due to
vacuum fluctuations and then we argue that they do not survive until
nucleosynthesis and decay along with the inflaton to produce a thermal bath
after preheating. Thus the only relevant remnant is the helicity \pm 3/2
gravitinos which can genuinely cause problem to nucleosynthesis.

</DOC>
<DOC>
<DOCNO> 119947 </DOCNO>
Galaxies behind the Milky Way and the Great Attractor


  Dust and stars in the plane of the Milky Way create a "Zone of Avoidance" in
the extragalactic sky. Galaxies are distributed in gigantic labyrinth
formations, filaments and great walls with occasional dense clusters. They can
be traced all over the sky, except where the dust within our own galaxy becomes
too thick - leaving about 25% of the extragalactic sky unaccounted for. Our
Galaxy is a natural barrier which constrains the studies of large-scale
structures in the Universe, the peculiar motion of our Local Group of galaxies
and other streaming motions (cosmic flows) which are important for
understanding formation processes in the Early Universe and for cosmological
models. Only in recent years have astronomers developed the techniques to peer
through the disk and uncover the galaxy distribution in the Zone of Avoidance.
I present the various observational multi-wavelength procedures (optical, far
infrared, near infrared, radio and X-ray) that are currently being pursued to
map the galaxy distribution behind our Milky Way. Particular emphasis is given
to discoveries in the Great Attractor region -- a from streaming motions
predicted huge overdensity centered behind the Galactic Plane. The recently
unveiled massive rich cluster A3627 seems to constitute the previously
unidentified core of the Great Attractor.

</DOC>
<DOC>
<DOCNO> 101748 </DOCNO>
A degeneration of stable morphisms and relative stable morphisms


  The introduction is modified in the revised version. Also, many typos and
errors were corrected.
  Let $W\to C$ be degeneration of smooth varieties so that the special fiber
has normal crossing singularity. In this paper, we first constructed the stack
of expanded degenerations of $W$. We then constructed the moduli space of
stable morphisms to this stack, which provides a degeneration of the moduli
spaces of stable morphisms associated to $W/C$. Using similar technique, for a
pair of smooth variety and a smooth divisor $(Z,D)$, we constructed the stack
of expanded relative pairs and then the moduli spaces of relative stable
morphisms to $(Z,D)$. In the subsequent paper we will construct the relative
Gromov-Witten invariants and prove a degeneration formula of Gromov-Witten
invariants.

</DOC>
<DOC>
<DOCNO> 70517 </DOCNO>
Active-Sterile neutrino oscillations and BBN+CMBR constraints


  We show how active-sterile neutrino oscillations in the early Universe can
play an interesting role in explaining the current observations of CMBR
anisotropies and light element abundances. We describe different possible
phenomenological scenarios in the interpretation of present data and how
active-sterile neutrino oscillations can provide a viable theoretical
framework.

</DOC>
<DOC>
<DOCNO> 67975 </DOCNO>
String breaking in zero-temperature lattice QCD


  The crossing from a static quark-antiquark system to a system of two
static-light mesons when the separation of the static quarks is increased is
calculated in zero-temperature lattice QCD. The mixing of these two states is
extracted from the lattice operators. We also discuss the breaking of an
excited string of a hybrid meson.

</DOC>
<DOC>
<DOCNO> 179040 </DOCNO>
Momentum Space Integral Equations for Three Charged Particles: Diagonal


  It has been a long-standing question whether momentum space integral
equations of the Faddeev type are applicable to reactions of three charged
particles, in particular above the three-body threshold. For, the presence of
long-range Coulomb forces has been thought to give rise to such severe
singularities in their kernels that the latter may lack the compactness
property known to exist in the case of purely short-range interactions.
Employing the rigorously equivalent formulation in terms of an
effective-two-body theory we have proved in a preceding paper [Phys. Rev. C
{\bf 61}, 064006 (2000)] that, for all energies, the nondiagonal kernels
occurring in the integral equations which determine the transition amplitudes
for all binary collision processes, possess on and off the energy shell only
integrable singularities, provided all three particles have charges of the same
sign, i.e., all Coulomb interactions are repulsive. In the present paper we
prove that, for particles with charges of equal sign, the diagonal kernels, in
contrast, possess one, but only one, nonintegrable singularity. The latter can,
however, be isolated explicitly and dealt with in a well-defined manner. Taken
together these results imply that modified integral equations can be
formulated, with kernels that become compact after a few iterations. This
concludes the proof that standard solution methods can be used for the
calculation of all binary (i.e., (in-)elastic and rearrangement) amplitudes by
means of momentum space integral equations of the effective-two-body type.

</DOC>
<DOC>
<DOCNO> 170733 </DOCNO>
Comment on "Measurement of time of arrival in quantum mechanics"


  The analysis of the model quantum clocks proposed by Aharonov et al. [Phys.
Rev. A 57 (1998) 4130 - quant-ph/9709031] requires considering evanescent
components, previously ignored. We also clarify the meaning of the operational
time of arrival distribution which had been investigated.

</DOC>
<DOC>
<DOCNO> 169664 </DOCNO>
All Optical Cellular Quantum Computer having Ancilla Bits for Operations


  A quantum cellular network with a qubit and ancilla bits in each cell is
proposed. The whole circuit works only with the help of external optical pulse
sequences. In the operation, some of the ancilla bits are activated, and
autonomous single- and two-qubit operations are made. In the sleep mode of a
cell, the decoherence of the qubit is negligibly small. Since only two cells at
most are active at once, the coherence can be maintained for a sufficiently
long time for practical purposes. A device structure using a quantum dot array
with possible operation and measurement schemes is also proposed.

</DOC>
<DOC>
<DOCNO> 69605 </DOCNO>
A Brane World Solution to the Cosmological Constant Problem


  We consider a model with two parallel (positive tension) 3-branes separated
by a distance $L$ in 5-dimensional spacetime. If the interbrane space is
anti-deSitter, or is not precisely anti-deSitter but contains no event
horizons, the effective 4-dimensional cosmological constant seen by observers
on one of the branes (chosen to be the visible brane) becomes exponentially
small as $L$ grows large.

</DOC>
<DOC>
<DOCNO> 10900 </DOCNO>
Ising model on nonorientable surfaces: Exact solution for the Moebius


  Closed-form expressions are obtained for the partition function of the Ising
model on an M x N simple-quartic lattice embedded on a Moebius strip and a
Klein bottle for finite M and N. The finite-size effects at criticality are
analyzed and compared with those under cylindrical and toroidal boundary
conditions. Our analysis confirms that the central charge is c=1/2.

</DOC>
<DOC>
<DOCNO> 68977 </DOCNO>
A finite-energy solution in Yang-Mills theory and quantum fluctuations


  A finite-energy solution of Yang-Mills theory with a nonstandard lagrangian
is provided. Properties of these solution are studied and also a possible
physical interpretation is given.

</DOC>
<DOC>
<DOCNO> 84270 </DOCNO>
Acoustics of early universe. I. Flat versus open universe models


  A simple perturbation description unique for all signs of curvature, and
based on the gauge-invariant formalisms is proposed to demonstrate that:
 (1) The density perturbations propagate in the flat radiation-dominated
universe in exactly the same way as electromagnetic or gravitational waves
propagate in the epoch of the matter domination.
 (2) In the open universe, sounds are dispersed by curvature. The space
curvature defines the minimal frequency $\omega_{\rm c}$ below which the
propagation of perturbations is forbidden.
  Gaussian acoustic fields are considered and the curvature imprint in the
perturbations spectrum is discussed.

</DOC>
<DOC>
<DOCNO> 9049 </DOCNO>
Theory of the evolutionary minority game


  We present a theory which describes a recently introduced model of an
evolving, adaptive system in which agents compete to be in the minority. The
agents themselves are able to evolve their strategies over time in an attempt
to improve their performance. The present theory explicitly demonstrates the
self-interaction, or so-called market impact, that agents in such systems
experience.

</DOC>
<DOC>
<DOCNO> 85466 </DOCNO>
Teleparallel Gravity and the Gravitational Energy-Momentum Density


  In the context of the teleparallel equivalent of general relativity, we show
that the energy-momentum density for the gravitational field can be described
by a true spacetime tensor. It is also invariant under local (gauge)
translations of the tangent space coordinates, but transforms covariantly only
under global Lorentz transformations. When the gauge gravitational field
equation is written in a purely spacetime form, it becomes the teleparallel
equivalent of Einstein's equation, and we recover M{\o}ller's expression for
the canonical gravitational energy-momentum pseudotensor.

</DOC>
<DOC>
<DOCNO> 70939 </DOCNO>
Status of the solutions to neutrino anomalies based on non-standard


  We review the status of the solutions to neutrino anomalies by
flavor-changing as well as flavor-diagonal neutrino interactions. While it is
difficult to explain the atmospheric neutrino data the solar neutrino data can
be well accounted for by the massless neutrino oscillation induced by such
non-standard neutrino interactions. We also discuss the possibility to test
such kind of interactions by the future neutrino oscillation experiments at
neutrino factories.

</DOC>
<DOC>
<DOCNO> 14005 </DOCNO>
Granular Shear Flow Dynamics and Forces : Experiment and Continuum


  We analyze the main features of granular shear flow through experimental
measurements in a Couette geometry and a comparison to a locally Newtonian,
continuum model of granular flow. The model is based on earlier hydrodynamic
models, adjusted to take into account the experimentally observed coupling
between fluctuations in particle motion and mean-flow properties.
Experimentally, the local velocity fluctuations are found to vary as a power of
the local velocity gradient. This can be explained by an effective viscosity
that diverges more rapidly as the random-close-packing density is approached
than is predicted by Enskog theory for dense hard sphere systems. Experiment
and theory are in good agreement, especially for the following key features of
granular flow: The flow is confined to a small shear band, fluctuations decay
approximately exponentially away from the sheared wall, and the shear stress is
approximately independent of shear rate. The functional forms of the velocity
and fluctuation profiles predicted by the model agree with the experimental
results.

</DOC>
<DOC>
<DOCNO> 69066 </DOCNO>
Automatic Loop Calculations with FeynArts, FormCalc, and LoopTools


  This article describes three Mathematica packages for the automatic
calculation of one-loop Feynman diagrams: the diagrams are generated with
FeynArts, algebraically simplified with FormCalc, and finally evaluated
numerically using the LoopTools package. The calculations are performed
analytically as far as possible, with results given in a form well suited for
numerical evaluation. The latter is straightforward with the utility programs
provided by FormCalc (e.g. for translation into Fortran code) and the
implementations of the one-loop integrals in LoopTools. The programs are also
equipped for calculations in supersymmetric models.

</DOC>
<DOC>
<DOCNO> 100963 </DOCNO>
Uniqueness of solutions to Hamilton-Jacobi equations arising in the


  We prove the uniqueness of the viscosity solution to the Hamilton-Jacobi
equation associated with a Bolza problem of the Calculus of Variations,
assuming that the Lagrangian is autonomous, continuous, superlinear, and
satisfies the usual convexity hypothesis. Under the same assumptions we prove
also the uniqueness, in a class of lower semicontinuous functions, of a
slightly different notion of solution, where classical derivatives are replaced
only by subdifferentials. These results follow from a new comparison theorem
for lower semicontinuous viscosity supersolutions of the Hamilton-Jacobi
equation, that is proved in the general case of lower semicontinuous
Lagrangians.

</DOC>
<DOC>
<DOCNO> 84667 </DOCNO>
Self-similar static solutions admitting a two-space of constant


  A recent result by Haggag and Hajj-Boutros is reviewed within
the framework of self-similar space-times, extending, in some sense, their
results and presenting a family of metrics consisting of all the static
spherically symmetric perfect fluid solutions admitting a homothety.

</DOC>
<DOC>
<DOCNO> 152614 </DOCNO>
Dualities in D=5, N=2 Supergravity, Black Hole Entropy, and AdS Central


  The issue of microstate counting for general black holes in D=5, N=2
supergravity coupled to vector multiplets is discussed from various viewpoints.
The statistical entropy is computed for the near-extremal case by using the
central charge appearing in the asymptotic symmetry algebra of AdS_2.
Furthermore, we show that the considered supergravity theory enjoys a duality
invariance which connects electrically charged black holes and magnetically
charged black strings. The near-horizon geometry of the latter turns out to be
AdS_3 x S^2, which allows a microscopic calculation of their entropy using the
Brown-Henneaux central charges in Cardy's formula. In both approaches we find
perfect agreement between statistical and thermodynamical entropy.

</DOC>
<DOC>
<DOCNO> 116694 </DOCNO>
First Observation of Self-Amplified Spontaneous Emission in a


  We present the first observation of Self-Amplified Spontaneous Emission
(SASE) in a free-electron laser (FEL) in the Vacuum Ultraviolet regime at 109
nm wavelength (11 eV). The observed free-electron laser gain (approx. 3000) and
the radiation characteristics, such as dependency on bunch charge, angular
distribution, spectral width and intensity fluctuations all corroborate the
existing models for SASE FELs.

</DOC>
<DOC>
<DOCNO> 9493 </DOCNO>
Mode Coupling Approach for spin-facilitated kinetic Ising models


  The d-dimensional n-spin facilitated kinetic Ising model is studied
analytically starting from usual master equations and their transformation into
a Fock-space representation. The evolution of relevant operators is rewritten
in terms of a projection formalism. The obtained frequency matrices and memory
terms are analyzed. Especially, the influences of the memory terms is
approached by using standard techniques of the usual mode coupling approach.
The temperature dependence of the relaxation times related to the n-spin
facilitated kinetic Ising model shows a weak non-Arrhenius behavior.
Furthermore, a characteristic stretched decay of the correlation function is
obtained.

</DOC>
<DOC>
<DOCNO> 169708 </DOCNO>
On the weak-coupling limit and complete positivity


  We consider two non-interacting systems embedded in a heat bath. If they
remain dynamically independent, physical inconsistencies are avoided only if
the single-system reduced dynamics is completely positive also beyond the
weak-coupling limit.

</DOC>
<DOC>
<DOCNO> 9408 </DOCNO>
Continuous weak measurement of the macroscopic quantum coherent


  The problem of continuous quantum measurement of coherent oscillations in an
individual quantum two-state system is studied for a generic model of the
measuring device. It is shown that for a symmetric detector, the
signal-to-noise ratio of the measurement, defined as the ratio of the amplitude
of the oscillation line in the output spectrum to background noise, is
independent of the coupling strength between oscillations and the detector, and
is equal to $(\hbar/\epsilon)^2$, where $\epsilon$ is the detector energy
sensitivity. The fundamental quantum limit of 4 imposed by this result on the
signal-to-noise ratio of the measurement with an ``ideal'' quantum-limited
detector reflects the general tendency of a quantum measurement to localize the
system in one of the eigenstates of the measured observable. These results are
applied to specific measurements of the quantum oscillations of magnetic flux
with a dc SQUID, and oscillations of charge measured with a Cooper-pair
electrometer. They are also used to calculate the energy sensitivity of a
quantum point contact as detector.

</DOC>
<DOC>
<DOCNO> 120511 </DOCNO>
An optical time-delay estimate for the double gravitational lens system


  We present optical I-band light curves of the gravitationally lensed double
QSO B1600+434 from observations obtained at the Nordic Optical Telescope (NOT)
between April 1998 and November 1999. The photometry has been performed by
simultaneous deconvolution of all the data frames, involving a numerical lens
galaxy model. Four methods have been applied to determine the time delay
between the two QSO components, giving a mean estimate of \Delta_t = 51+/-4
days (95% confidence level). This is the fourth optical time delay ever
measured. Adopting a Omega=0.3, Lambda=0 Universe and using the mass model of
Maller et al. (2000), this time-delay estimate yields a Hubble parameter of
H_0=52 (+14, -8) km s^-1 Mpc^-1 (95% confidence level) where the errors include
time-delay as well as model uncertainties. There are time-dependent offsets
between the two (appropriately shifted) light curves that indicate the presence
of external variations due to microlensing.

</DOC>
<DOC>
<DOCNO> 80902 </DOCNO>
Z2 monopoles in D=2+1 SU(2) lattice gauge theory


  We calculate the Euclidean action of a pair of Z2 monopoles (instantons), as
a function of their spatial separation, in D=2+1 SU(2) lattice gauge theory. We
do so both above and below the deconfining transition at T=Tc. At high T, and
at large separation, we find that the monopole `interaction' grows linearly
with distance: the flux between the monopoles forms a flux tube (exactly like a
finite portion of a Z2 domain wall) so that the monopoles are linearly
confined. At short distances the interaction is well described by a Coulomb
interaction with, at most, a very small screening mass, possibly equal to the
Debye electric screening mass. At low T the interaction can be described by a
simple screened Coulomb (i.e. Yukawa) interaction with a screening mass that
can be interpreted as the mass of a `constituent gluon'. None of this is
unexpected, but it helps to resolve some apparent controversies in the recent
literature.

</DOC>
<DOC>
<DOCNO> 100203 </DOCNO>
Generalisation de formules de type Waring


  We evaluate the symmetric functions $e_k$, $h_k$ and $p_k$ on the alphabet
$\{x_r/(1-tx_r)\}$ by elementary methods and give the related generating
functions. Our formulas lead to a new and short proof of an ex-conjecture of
Lassalle, which was proved by Lascoux and Lassalle in the framework of
$\lambda$-rings theory.

</DOC>
<DOC>
<DOCNO> 83221 </DOCNO>
Modeling the Uncertainty in Complex Engineering Systems


  Existing procedures for model validation have been deemed inadequate for many
engineering systems. The reason of this inadequacy is due to the high degree of
complexity of the mechanisms that govern these systems. It is proposed in this
paper to shift the attention from modeling the engineering system itself to
modeling the uncertainty that underlies its behavior. A mathematical framework
for modeling the uncertainty in complex engineering systems is developed. This
framework uses the results of computational learning theory. It is based on the
premise that a system model is a learning machine.

</DOC>
<DOC>
<DOCNO> 100448 </DOCNO>
A new class of entanglement measures


  We introduce new entanglement measures on the set of density operators on
tensor product Hilbert spaces. These measures are based on the greatest cross
norm on the tensor product of the sets of trace class operators on Hilbert
space. We show that they satisfy the basic requirements on entanglement
measures discussed in the literature, including convexity, invariance under
local unitary operations and non-increase under local quantum operations and
classical communication.

</DOC>
<DOC>
<DOCNO> 68283 </DOCNO>
Anisotropy of Dynamical Fluctuations as a Probe for Soft and Hard


  It is shown using Lund Monte Carlo that, unlike the average properties of the
hadronic system inside jets, the anisotropy of dynamical fluctuations in these
systems changes abruptly with the variation of the cut parameter $y_cut$. A
transition point exists, where the dynamical fluctuations in the hadronic
system inside jet behave like those in soft hadronic collisions. Thus the
anisotropy property of the dynamical fluctuations can serve as a probe for the
soft and hard processes in high energy collisions.

</DOC>
<DOC>
<DOCNO> 101897 </DOCNO>
Toric morphisms and fibrations of toric Calabi-Yau hypersurfaces


  Special fibrations of toric varieties have been used by physicists, e.g. the
school of Candelas, to construct dual pairs in the study of Het/F-theory
duality. Motivated by this, we investigate in this paper the details of toric
morphisms between toric varieties. In particular, a complete toric description
of fibers - both generic and non-generic -, image, and the flattening
stratification of a toric morphism are given. Two examples are provided to
illustrate the discussions. We then turn to the study of the restriction of a
toric morphism to a toric hypersurface. The details of this can be understood
by the various restrictions of a line bundle with a section that defines the
hypersurface. These general toric geometry discussions give rise to a
computational scheme for the details of a toric morphism and the induced
fibration of toric hypersurfaces therein. We apply this scheme to study the
family of 4-dimensional elliptic Calabi-Yau toric hypersurfaces that appear in
a recent work of Braun-Candelas-dlOssa-Grassi. The Maple codes that are
employed for the computation are provided. Some directions for future work are
listed in the end.

</DOC>
<DOC>
<DOCNO> 9999 </DOCNO>
Bose-Einstein condensation of rubidium atoms in a triaxial TOP-trap


  We report the results of experiments with Bose-Einstein condensates of
rubidium atoms in a triaxial TOP-trap, presenting measurements of the
condensate fraction and the free expansion of a condensate released from the
trap. The experimental apparatus and the methods used to calibrate the magnetic
trapping fields are discussed in detail. Furthermore, we compare the
performance of our apparatus with other TOP-traps and discuss possible limiting
factors for the sizes of condensates achievable in such traps.

</DOC>
<DOC>
<DOCNO> 39838 </DOCNO>
Capacitance of Silicon Pixels


  Capacitance measurements have been made on silicon pixel sensors of types n+
on n, p+ on n, and n+ on p. The arrays test a variety of implant and gap
widths, and the n+ on n devices test several p-stop designs. The measurements
examine inter-pixel and backplane contributions and include studies of
temperature dependence. Measurements were made before and after irradiation
with fluences relevant to LHC experiments and Fermilab Tevatron Run 2.

</DOC>
<DOC>
<DOCNO> 13178 </DOCNO>
Memory Effect in Silicon Nitride in Silicon Devices


  The dominant dielectric used currently in silicon devices is silicon oxide.
Its application for future devices will be impeded by several fundamental
limitations which lead to low reliability of semiconductor devices and to the
necessity of alternative dielectrics. Amorphous silicon nitride and oxynitride
are considered now as alternative to silicon oxide in future devices. One of
the unique property of amorphous silicon nitride is the electron and hole
capture by the deep traps with extremely long life time (10 years) in the
captured state (the memory effect). This property is employed in memory devices
and microprocessors in computers. Despite numerous efforts the nature of traps
responsible for the memory effect in this material is so far unclear. In this
paper we discuss the nature of such traps using the quantum-chemical
simulation. The calculations show that the defects responsible for the electron
and hole capture in amorphous silicon nitride can be the Si-Si defects created
by excess silicon atoms.

</DOC>
<DOC>
<DOCNO> 67793 </DOCNO>
Production of fermions in models of string cosmology


  Production of spin 1/2 fermions and gravitinos by the standard mechanism of
amplification of quantum fluctuations during the dilaton-driven inflation phase
in models of string cosmology is highly suppressed. Constraints on string
cosmology models from gravitational production of gravitinos, contrary to
expectations, are similar to constraints on other models.

</DOC>
<DOC>
<DOCNO> 100054 </DOCNO>
The Harnack estimate for the Yamabe flow on CR manifolds of dimension 3


  We deform the contact form by the amount of the Tanaka-Webster curvature on a
closed spherical $CR$ three-manifold. We show that if a contact form evolves
with free torsion and positive Tanaka-Webster curvature as initial data, then a
certain Harnack inequality for the Tanaka-Webster curvature holds.

</DOC>
<DOC>
<DOCNO> 69821 </DOCNO>
Neutrino Oscillations Induced by Two-loop Radiative Mechanism


  Two-loop radiative mechanism, when combined with an U(1)_{L'} symmetry
generated by L_e-L_\mu-L_\tau (=L'), is shown to provide an estimate of \Delta
m^2_{\odot}/\Delta m^2_{atm} $\sim$ \epsilon m_e/m_\tau, where \epsilon
measures the U(1)_{L'}-breaking. Since \Delta m^2_{atm} $\sim 3.5x10^{-3} eV^2,
we find that \Delta m^2_{\odot} $\sim$ \epsilon x10^{-6} eV^2, which will fall
into the allowed region of the LOW solution to the solar neutrino problem for
\epsilon $\sim$ 0.1.

</DOC>
<DOC>
<DOCNO> 99871 </DOCNO>
Towards the trace formula for convex-cocompact groups


  We derive a formula for the regularized trace of operators with compact
spectrum which act on the space of square integrable functions on the quotient
of a semisimple Liegroup of real rank one by a convex-cocompact subgroup. The
sum of normalized orbital integrals associated to the hyperbolic conjugacy
classes of this subgroup is an invariant distribution on the group, and we
state precise conjecture about its Fouriertransform. We apply our trace formula
to resolvent kernels. This yields functional equations of Selberg zeta
functions and information about their singularities. The paper leaves open
several interesting questions concerning the proof of the conjecture mentioned
above on the one hand (this has to do with estimating the growth of the
Eisenstein series as the spectral parameter turns to infinity), and the
integrality of the multiplicities and of certain residues on the other hand.

</DOC>
<DOC>
<DOCNO> 39888 </DOCNO>
Measurement of the Photon Structure Function at High Q^2 at LEP


  The structure functions of real and virtual photons are derived from cross
section measurements of the reaction e^+e^ -> e^+e^- + hadrons at LEP. The
reaction is studied at \sqrt{s} ~ 91 GeV with the L3 detector. One of the final
state electrons is detected at a large angle relative to the beam direction,
leading to Q^2 values between 40 GeV^2 and 500 GeV^2. The other final state
electron is either undetected or it is detected at a four-momentum transfer
squared P^2 between 1 GeV^2 and 8 GeV^2. These measurements are compared with
predictions of the Quark Parton Model and other QCD based models.

</DOC>
<DOC>
<DOCNO> 99998 </DOCNO>
Deformation Quantization of Coadjoint Orbits


  A method for the deformation quantization of coadjoint orbits of semisimple
Lie groups is proposed. It is based on the algebraic structure of the orbit.
Its relation to geometric quantization and differentiable deformations is
explored.

</DOC>
<DOC>
<DOCNO> 13368 </DOCNO>
Influence of the flow on the anchoring of nematic liquid crystals on a


  The influence of capillary flow on the alignment of the nematic liquid
crystal MBBA on fatty acid Langmuir-Blodgett monolayers was studied by optical
second-harmonic generation. The surface dipole sensitivity of the technique
allows probing the orientation of the first liquid crystal monolayer in the
presence of the liquid crystal bulk. It was found that capillary flow causes
the first monolayer of liquid crystal molecules in contact with the fatty acid
monolayer to be oriented in the flow direction with a large pretilt (78
degrees), resulting in a quasi-planar alignment with splay-bend deformation of
the nematic director in the bulk. itself is affected by the flow. The
quasi-planar flow-induced alignment was found to be metastable. Once the flow
ceases, circular domains of homeotropic orientation nucleate in the sample and
expand until the whole sample becomes homeotropic. This relaxation process from
flow-induced quasi-planar to surface-induced homeotropic alignment was also
monitored by SHG. It was found that in the homeotropic state the first nematic
layer presents a pretilt of 38 degrees almost isotropically distributed in the
plane of the cell, with a slight preference for the direction of the previous
flow.

</DOC>
<DOC>
<DOCNO> 71186 </DOCNO>
Quantum Field Treatment of DCC Dynamics


  A practical quantum-field treatment is developed for systems endowed with an
effective mass function depending on both space and time and a schematic
application illustrates the quantitative importance of quantum fluctuations in
the dynamics of disoriented chiral condensates.

</DOC>
<DOC>
<DOCNO> 101936 </DOCNO>
Application of the hybrid stochastic-deterministic minimization method


  A method for the identification of small inhomogeneities from a surface data
is presented in the framework of an inverse scattering problem for the
Helmholtz equation. Using the assumptions of smallness of the scatterers one
reduces this inverse problem to an identification of the positions of the small
scatterers. These positions are found by a global minimization search. Such a
search is implemented by a novel Hybrid Stochastic-Deterministic Minimization
method. The method combines random tries and a deterministic minimization. The
effectiveness of this approach is illustrated by numerical experiments. In the
modeling part our method is valid when the Born approximation fails. In the
numerical part, an algorithm for the estimate of the number of the small
scatterers is proposed.

</DOC>
<DOC>
<DOCNO> 84164 </DOCNO>
Moving Mirrors and Thermodynamic Paradoxes


  Quantum fields responding to "moving mirrors" have been predicted to give
rise to thermodynamic paradoxes. I show that the assumption in such work that
the mirror can be treated as an external field is invalid: the exotic
energy-transfer effects necessary to the paradoxes are well below the scales at
which the model is credible. For a first-quantized point-particle mirror, it
appears that exotic energy-transfers are lost in the quantum uncertainty in the
mirror's state. An accurate accounting of these energies will require a model
which recognizes the mirror's finite reflectivity, and almost certainly a model
which allows for the excitation of internal mirror modes, that is, a
second-quantized model.

</DOC>
<DOC>
<DOCNO> 83043 </DOCNO>
Refinement of a Structured Language Model


  A new language model for speech recognition inspired by linguistic analysis
is presented. The model develops hidden hierarchical structure incrementally
and uses it to extract meaningful information from the word history - thus
enabling the use of extended distance dependencies - in an attempt to
complement the locality of currently used n-gram Markov models. The model, its
probabilistic parametrization, a reestimation algorithm for the model
parameters and a set of experiments meant to evaluate its potential for speech
recognition are presented.

</DOC>
<DOC>
<DOCNO> 170056 </DOCNO>
Quantum Time-Frequency Transforms


  Time-frequency transforms represent a signal as a mixture of its time domain
representation and its frequency domain representation. We present efficient
algorithms for the quantum Zak transform and quantum Weyl-Heisenberg transform.

</DOC>
<DOC>
<DOCNO> 179054 </DOCNO>
The q-Deformed NJL Model "Revisited"


  In this work we investigate the chiral symmetry breaking in the q-deformed
version of the NJL Model and its consequent mass generation mechanism . We show
that the deformation of the NJL model, in the mean field approximation, may
take into account correlations that go beyond the mean field and, in a certain
limit, approaches the more realistic lattice calculations.

</DOC>
<DOC>
<DOCNO> 121070 </DOCNO>
s- and r-process elements in two very metal-poor stars


  New measurements of neutron-capture elements are presented for two very
metal-poor stars ([Fe/H] ~ -3). One (LP 625-44) has an s-process signature
believed to be due to mass transfer from a now-extinct metal-poor AGB
companion, and the second (CS 22897-008) is one of a number of very metal-poor
stars having high [Sr/Ba] ratios which is not expected from the r-process. In
the s-process star, many elements including lead have been detected, providing
strong constraints on the 13C pocket in the now-extinct AGB star. In the
Sr-rich star, Zn, Y, and Zr are also seen to be overabundant, and several
possible nucleosynthesis mechanisms are discussed.

</DOC>
<DOC>
<DOCNO> 118351 </DOCNO>
Optical, near-infrared and hard X-ray observations of SAXJ1353.9+1820: a


  We present the results of a follow-up ASCA observation and multicolour
optical and near-infrared photometry carried out at the 3.5-m Italian National
Telescope Galileo of SAXJ1353.9+1820. This object, serendipitously discovered
by BeppoSAX in the 5-10 keV band, has been spectroscopically identified as a
red quasar at z=0.217. The combined X-ray and optical-infrared data reveal the
presence of a moderately luminous X-ray source (~ 10^{44} erg s^{-1}) obscured
by a column density of the order of 10^{22} cm^{-2} in a otherwise optically
passive early-type galaxy. The implications for the nature of red quasars and
their possible contribution to the hard X-ray background are briefly outlined.

</DOC>
<DOC>
<DOCNO> 119737 </DOCNO>
Radio Sources in Low-Luminosity Active Galactic Nuclei. II. VLBI


  We have used the VLBA at 5 GHz to observe all galaxies with nuclear radio
flux densities above 3.5 mJy found in a VLA survey at 15 GHz of a sample of
nearby LINER galaxies. All galaxies were detected revealing high brightness
temperature ($T_{b} \ga 10^8$ K) radio sources. Free-free emission is unlikely
since it greatly overpredicts the soft X-ray luminosities. We infer the
presence of AGN-like, non-thermal radio emission most likely powered by
under-fed black holes. Together with our VLA sample we estimate from our
observations that at least half of LINER galaxies host genuine AGN. We find no
evidence for highly inverted radio cores as predicted in the ADAF model: the
(non-simultaneous) spectral indices are on average around $\alpha=0.0$. In the
two brightest sources we detect some extended emission, which appears to
originate in jets in at least one of these galaxies. Together with the spectral
indices this suggests that the nuclear emission at centimeter radio waves is
largely dominated by emission from radio jets, very similar to the situation in
more luminous AGN. The energy released in these jets could be a significant
fraction of the energy budget in the accretion flow.

</DOC>
<DOC>
<DOCNO> 80755 </DOCNO>
Decay Constants of B and D Mesons from Non-perturbatively Improved


  The decay constants of B, D and K mesons are computed in quenched lattice QCD
at two different values of the coupling. The action and operators are O(a)
improved with non-perturbative coefficients. The results are
f_B=195(6)(+24/-23) MeV, f_D=206(4)(+17/-10) MeV, f_B_s=220(6)(+23/-28) MeV,
f_D_s=229(3)(+23/-12) MeV and f_K= 150(3)(+12/-8) MeV. Systematic errors are
discussed in detail. Results for vector decay constants, flavour symmetry
breaking ratios of decay constants, the pseudoscalar-vector mass splitting and
D meson masses are also presented.

</DOC>
<DOC>
<DOCNO> 151492 </DOCNO>
On Relation Between Moyal and Kontsevich Quantum Products. Direct


  In his celebrated paper Kontsevich has proved a theorem which manifestly
gives a quantum product (deformation quantization formula) and states that
changing coordinates leads to gauge equivalent star products. To illuminate his
procedure, we make an arbitrary change of coordinates in the Moyal product and
obtain the deformation quantization formula up to the third order. In this way,
the Poisson bi-vector is shown to depend on \hbar and not to satisfy the Jacobi
identity. It is also shown that the values of coefficients in the formula
obtained follow from associativity of the star product.

</DOC>
<DOC>
<DOCNO> 170750 </DOCNO>
Tomography of Quantum Operations


  Quantum operations describe any state change allowed in quantum mechanics,
including the evolution of an open system or the state change due to a
measurement. In this letter we present a general method based on quantum
tomography for measuring experimentally the matrix elements of an arbitrary
quantum operation. As input the method needs only a single entangled state. The
feasibility of the technique for the electromagnetic field is shown, and the
experimental setup is illustrated based on homodyne tomography of a twin-beam.

</DOC>
<DOC>
<DOCNO> 123108 </DOCNO>
The Dynamics of Sinking Satellites Around Disk Galaxies: A Poor Man's


  We have developed a simple yet surprisingly accurate analytic scheme for
tracking the dynamical evolution of substructure within larger dark halos. The
scheme incorporates the effects of dynamical friction, tidal mass loss and
tidal heating via physically motivated approximations. Using our scheme, we can
predict the orbital evolution and mass-loss history of individual subhalos in
detail. We are also able to determine the impact and importance of the
different physical processes on the dynamical evolution of the subhalos. To
test and calibrate this model, we compare it with a set of recent
high-resolution numerical simulations of mergers between galaxies and small
companions. We find that we can reproduce the orbits and mass-loss rates seen
in all of these simulations with considerable accuracy, using a single set of
values for the three free parameters in our model. Computationally, our scheme
is more than 1000 times faster than the simplest of the high-resolution
numerical simulations. This means that we can carry out detailed and
statistically meaningful investigations into the characteristics of the subhalo
population in different cosmologies, the stripping and disruption of the
subhalos, and the interactions of the subhalos with other dynamical structures
such as a thin disk. This last point is of particular interest given the
ubiquity of minor mergers in hierarchical models. In this regard, our method's
simplicity and speed makes it particularly attractive for incorporation into
semi-analytic models of galaxy formation.

</DOC>
<DOC>
<DOCNO> 99445 </DOCNO>
Application of Tree-like Structure of Graph to Matrix Analysis


  Formulas for matrix determinants, algebraic adjunctions, characteristic
polynomial coefficients, components of eigenvectors are obtained in the form of
signless sums of matrix elements products taking by special graphs. Signless
formulas are very important for singular and stochastic problems. They are also
useful for spectral analysis of large very sparse matrices.

</DOC>
<DOC>
<DOCNO> 10591 </DOCNO>
Dynamics of Entangled Polymeric Fluids in Two-roll Mill studied via


  We present the experimental results on a series of high molecular weight,
entangled polystyrene solutions subjected to a ``mixed'' shear and elongational
flow-type generated in a co-rotating two-roll mill. For steady-flows as well as
for start-up of flows from rest, we used two different optical methods to study
the dynamics of entangled polymeric fluids: two-color flow birefringence (TCFB)
and dynamic light scattering (DLS). Using the TCFB method, we measured the
birefringence, $\Delta n$, and the orientation angle, $\chi$, of the optic axes
in the solution and thereby the generalized viscosity function, $\eta$ (with
the use of stress-optical relations). The DLS method was applied to measure the
velocity-gradient, \gdot, and the flow-type parameter $\lambda$ for the polymer
solutions under flow conditions identical to the TCFB measurements. For low
deformation rates the symmetry of the flow-field was reduced with the use of
polymeric fluids compared to that seen with a Newtonian fluid. A molecular
constitutive Doi-Edwards-Marrucci-Grizzuti (DEMG) model which includes polymer
chain-stretching effects, has been used to numerically simulate the predictions
for $\Delta n$, $\chi$, and $\eta$ under steady flow conditions for the
polystyrene fluids with \gdot and $\lambda$, measured via DLS, as inputs to the
model. A detailed comparison of the DEMG model predictions with the
experimental results shows that the model works qualitatively as well as
quantitatively for the low and intermediate deformation rates, but fails at
high rates of deformation by predicting a stronger chain-stretching than
observed experimentally. The effect of polymer molecular-weight and number of
entanglements per chain are highlighted.

</DOC>
<DOC>
<DOCNO> 9152 </DOCNO>
Dimensional Crossover by a Local Inhomogeneity in Soliton-Pair


  Soliton-pair nucleation rates Gamma = A exp(-B) are studied in highly-biased
sine-Gordon systems with a local inhomogeneity for both a thermal activation
regime and a quantum tunneling regime. It is found that the local inhomogeneity
strongly affects the nucleation rates by modifying the bias-dependence of the
exponent B. This change in the exponent B is explained as a dimensional
crossover caused by the local inhomogeneity. It is also shown that there is
another crossover, at which A becomes independent of the system size.

</DOC>
<DOC>
<DOCNO> 12996 </DOCNO>
Spin Driven Jahn-Teller Distortion in a Pyrochlore system


  The ground-state properties of the spin-1 antiferromagnetic Heisenberg model
on the corner-sharing tetrahedra, pyrochlore lattice, is investigated. By
breaking up each spin into a pair of 1/2-spins, the problem is reduced to the
equivalent one of the spin-1/2 tetrahedral network in analogy with the valence
bond solid state in one dimension. The twofold degeneracy of the spin-singlets
of a tetrahedron is lifted by a Jahn-Teller mechanism, leading to a cubic to
tetragonal structural transition. It is proposed that the present mechanism is
responsible for the phase transition observed in the spin-1 spinel compounds
ZnV$_2$O$_4$ and MgV$_2$O$_4$.

</DOC>
<DOC>
<DOCNO> 152558 </DOCNO>
Open Branes and Little Strings


  This is a short review of the newly discovered ODp-theories that are
non-gravitational six-dimensional theories defined as the decoupling limit of
NS5-branes in the presence of a near-critical (p+1)-form RR fields. We discuss
the motivation for these new theories, their definitions and properties, and
their relation to NCOS theory, OM theory and Little String Theory, focusing on
the cases p=1,2.

</DOC>
<DOC>
<DOCNO> 170777 </DOCNO>
Decay of an excited atom near an absorbing microsphere


  Spontaneous decay of an excited atom near a dispersing and absorbing
microsphere of given complex permittivity that satisfies the Kramers-Kronig
relations is studied, with special emphasis on a Drude-Lorentz permittivity.
Both the whispering gallery field resonances below the band gap (for a
dielectric sphere) and the surface-guided field resonances inside the gap (for
a dielectric or a metallic sphere) are considered. Since the decay rate mimics
the spectral density of the sphere-assisted ground-state fluctuation of the
radiation field, the strengths and widths of the field resonances essentially
determine the feasible enhancement of spontaneous decay. In particular, strong
enhancement can be observed for transition frequencies within the interval in
which the surface-guided field resonances strongly overlap. When material
absorption becomes significant, then the highly structured emission pattern
that can be observed when radiative losses dominate reduces to that of a
strongly absorbing mirror. Accordingly, nonradiative decay becomes dominant. In
particular, if the distance between the atom and the surface of the microsphere
is small enough, the decay becomes purely nonradiative.

</DOC>
<DOC>
<DOCNO> 8985 </DOCNO>
Determination of ferroelectric compositional phase transition using


  We employ a new method for studying compositionally disordered ferroelectric
oxides. This method is based on the virtual crystal approximation (VCA), in
which two or more component potentials are averaged into a composite atomic
potential. In our method, we construct a virtual atom with the correctly
averaged atomic size and atomic eigenvalues. We have used our new method to
study the composition dependent phase transition in Pb(Zr_{1-x}Ti_x)O_3 lying
between x=0.5 and x=0.4. We correctly predict the experimentally determined
phase transition from the tetragonal phase to a low-temperature rhombohedral
phase between these two compositions.

</DOC>
<DOC>
<DOCNO> 150593 </DOCNO>
Non-Planar String Networks on Tori


  Type II strings in D=5 contain particle-like 1/8 supersymmetric BPS states.
In this note we give a string-network representation of such states by
considering (periodic) non-planar $(p,q,r)$-string networks of eight
dimensional type II string theory on $T^3$. We obtain the BPS mass formula of
such states, in terms of charges and generating-vectors of the torus, and show
its invariance under an $SL(3, Z)\times SL(3, Z)$ group of transformations.
Results are then generalized to string-networks associated with the $SL(5, Z)$
$U$-duality in seven dimensions. We also discuss reinterpretation of the above
$(D=5)$ mass formula in terms of BPS states in world-volume theories of
$U2$-branes in D=8.

</DOC>
<DOC>
<DOCNO> 102346 </DOCNO>
Deformations of the Boson $sp(4,R)$ Representation and its Subalgebras


  The boson representation of the sp(4,R) algebra and two distinct deformations
of it, are considered, as well as the compact and noncompact subalgebras of
each. The initial as well as the deformed representations act in the same Fock
space.
  One of the deformed representation is based on the standard q-deformation of
the boson creation and annihilation operators. The subalgebras of sp(4,R)
(compact u(2) and three representations of the noncompact u(1,1) are also
deformed and are contained in this deformed algebra. They are reducible in the
action spaces of sp(4,R) and decompose into irreducible representations.
    The other deformed representation, is realized by means of a transformation
of the q-deformed bosons into q-tensors (spinor-like) with respect to the
standard deformed su(2). All of its generators are deformed and have
expressions in terms of tensor products of spinor-like operators. In this case,
an other deformation of su(2) appears in a natural way as a subalgebra and can
be interpreted as a deformation of the angular momentum algebra so(3). Its
representation is reducible and decomposes into irreducible ones that yields a
complete description of the same.

</DOC>
<DOC>
<DOCNO> 10615 </DOCNO>
The Revised Quantum Mechanical Theory of the Optical Activity of


  In this paper we present the revised view on the optical activity of crystals
based on the model of two dumped coupled oscillators. The results are compared
with the results of the same problem solved before and it is presented that the
results of the quantum mechanical model are the generalization of the classical
model only and they do not introduce the new terms of quantum mechanical
nature. The results are discussed with regard to the rotational strengths of
normal modes of vibrations and the formula for the complex rotatory power
containing the rotational strengths is presented.

</DOC>
<DOC>
<DOCNO> 11954 </DOCNO>
Exact Potts Model Partition Functions on Strips of the Honeycomb Lattice


  We present exact calculations of the partition function of the $q$-state
Potts model on (i) open, (ii) cyclic, and (iii) M\"obius strips of the
honeycomb (brick) lattice of width $L_y=2$ and arbitrarily great length. In the
infinite-length limit the thermodynamic properties are discussed. The
continuous locus of singularities of the free energy is determined in the $q$
plane for fixed temperature and in the complex temperature plane for fixed $q$
values. We also give exact calculations of the zero-temperature partition
function (chromatic polynomial) and $W(q)$, the exponent of the ground-state
entropy, for the Potts antiferromagnet for honeycomb strips of type (iv)
$L_y=3$, cyclic, (v) $L_y=3$, M\"obius, (vi) $L_y=4$, cylindrical, and (vii)
$L_y=4$, open. In the infinite-length limit we calculate $W(q)$ and determine
the continuous locus of points where it is nonanalytic. We show that our exact
calculation of the entropy for the $L_y=4$ strip with cylindrical boundary
conditions provides an extremely accurate approximation, to a few parts in
$10^5$ for moderate $q$ values, to the entropy for the full 2D honeycomb
lattice (where the latter is determined by Monte Carlo measurements since no
exact analytic form is known).

</DOC>
<DOC>
<DOCNO> 71148 </DOCNO>
QCD sum rule analysis of the charmonium system: The charm quark mass


  In this work, the charm quark mass is obtained from a QCD sum rule analysis
of the charmonium system. In our investigation we include results from
non-relativistic QCD at next-to-next-to-leading order. Using the pole mass
scheme, we obtain a value of $M_c=1.70\pm 0.13$ GeV for the charm pole mass.
The introduction of a potential-subtracted mass leads to an improved scale
dependence. The running ${\rm \MSb}$-mass is then determined to be
$m_{c}(m_{c}) = 1.23 \pm 0.09$ GeV.

</DOC>
<DOC>
<DOCNO> 85452 </DOCNO>
Third post-Newtonian dynamics of compact binaries: Noetherian conserved


  A Lagrangian from which derive the third post-Newtonian (3PN) equations of
motion of compact binaries (neglecting the radiation reaction damping) is
obtained. The 3PN equations of motion were computed previously by Blanchet and
Faye in harmonic coordinates. The Lagrangian depends on the harmonic-coordinate
positions, velocities and accelerations of the two bodies. At the 3PN order,
the appearance of one undetermined physical parameter \lambda reflects an
incompleteness of the point-mass regularization used when deriving the
equations of motion. In addition the Lagrangian involves two unphysical
(gauge-dependent) constants r'_1 and r'_2 parametrizing some logarithmic terms.
The expressions of the ten Noetherian conserved quantities, associated with the
invariance of the Lagrangian under the Poincar\'e group, are computed. By
performing an infinitesimal ``contact'' transformation of the motion, we prove
that the 3PN harmonic-coordinate Lagrangian is physically equivalent to the 3PN
Arnowitt-Deser-Misner Hamiltonian obtained recently by Damour, Jaranowski and
Sch\"afer.

</DOC>
<DOC>
<DOCNO> 8628 </DOCNO>
Current bistability and hysteresis in strongly correlated quantum wires


  Nonequilibrium transport properties are determined exactly for an
adiabatically connected single channel quantum wire containing one impurity.
Employing the Luttinger liquid model with interaction parameter $g$, for very
strong interactions $g\lapx 0.2$, and sufficiently low temperatures, we find an
S-shaped current-voltage relation. The unstable branch with negative
differential conductance gives rise to current oscillations and hysteretic
effects. These non perturbative and non linear features appear only out of
equilibrium.

</DOC>
<DOC>
<DOCNO> 9718 </DOCNO>
Ground-States of Two Directed Polymers


  Joint ground states of two directed polymers in a random medium are
investigated. Using exact min-cost flow optimization the true two-line
ground-state is compared with the single line ground state plus its first
excited state. It is found that these two-line configurations are (for almost
all disorder configurations) distinct implying that the true two-line
ground-state is non-separable, even with 'worst-possible' initial conditions.
The effective interaction energy between the two lines scales with the system
size with the scaling exponents 0.39 and 0.21 in 2D and 3D, respectively.

</DOC>
<DOC>
<DOCNO> 117982 </DOCNO>
On the Perturbations of Viscous Rotating Newtonian Fluids


  The perturbations of weakly-viscous, barotropic, non-self-gravitating,
Newtonian rotating fluids are analyzed via a single partial differential
equation. The results are then used to find an expression for the
viscosity-induced normal-mode complex eigenfrequency shift, with respect to the
case of adiabatic perturbations. However, the effects of viscosity are assumed
to have been incorporated in the unperturbed (equilibrium) model. This paper is
an extension of the normal-mode formalism developed by Ipser & Lindblom for
adiabatic pulsations of purely-rotating perfect fluids. The formulas derived
are readily applicable to the perturbations of thin and thick accretion disks.
We provide explicit expressions for thin disks, employing results from previous
relativistic analyses of adiabatic normal modes of oscillation. In this case,
we find that viscosity causes the fundamental p- and g- modes to grow while the
fundamental c-mode could have either sign of the damping rate.

</DOC>
<DOC>
<DOCNO> 68294 </DOCNO>
Electroweak baryogenesis from preheating


  The origin of the matter-antimatter asymmetry remains one of the most
fundamental problems of cosmology. In this talk I present a novel scenario for
baryogenesis at the electroweak scale, without the need for a first order phase
transition. It is based on the out of equilibrium resonant production of long
wavelength Higgs and gauge configurations, at the end of a period of inflation,
which induces a large rate of sphaleron transitions, before thermalization at a
temperature below critical.

</DOC>
<DOC>
<DOCNO> 152569 </DOCNO>
M -theory on AdS_4 x Q^{111}: The complete Osp(2|4) x SU(2) x SU(2) x


  In this paper by means of harmonic analysis we derive the complete spectrum
of Osp(2|4) x SU(2) x SU(2) x SU(2) multiplets that one obtains compactifying
D=11 supergravity on the homogeneous space Q^{111}. In particular we analyze
the structure of the short multiplets and compare them with the corresponding
composite operators of the N=2 conformal field theory dual to such a
compactification, found in a previous publication. We get complete agreement
between the quantum numbers of the supergravity multiplets on one side and
those of the conformal operators on the other side, confirming the structure of
the conjectured SCFT. However the determination of the actual spectrum by
harmonic analysis teaches us a lot more: indeed we find out which multiplets
are present for each representation of the isometry group, how many they are,
the exact values of the hypercharge and of the energy for each multiplet.

</DOC>
<DOC>
<DOCNO> 85526 </DOCNO>
A Multiple-Grid-Patch Evolution Scheme for 3-D Black Hole Excision


  When using black hole excision to numerically evolve a fully generic black
hole spacetime, most 3-D 3+1 codes use an $xyz$-topology (spatial) grid. In
such a grid, an $r = \constant$ excision surface must be approximated by an
irregular and non-smooth "staircase-shaped" excision grid boundary, which may
introduce numerical instabilities into the evolution. In this paper I describe
an alternate scheme, which uses multiple grid patches, each with topology $\{r
\times ({\rm angular coordinates})\}$, to cover the slice outside the $r =
\constant$ excision surface. The excision grid boundary is now smooth, so the
evolution should be less prone to instabilities. With 4th order finite
differencing, this code evolves Kerr initial data to ${\sim} 60M$ using the ADM
equations; I'm currently implementing the BSSN equations in it in the hope that
this will improve the stability.

</DOC>
<DOC>
<DOCNO> 71524 </DOCNO>
Texture Specific Mass Matrices and CP violating asymmetry in B^o_d({\bar


  In the context of texture 4 - zero and texture 5 - zero hierarchical quark
mass matrices, CP violating asymmetry in $B^o_d({\bar B}^o_d) \to \psi K_S$
(sin2$\beta$) has been evaluated by considering quark masses at $m_Z$ scale.
For a particular viable texture 4 - zero mass matrix the range of sin2\beta is:
0.27 - 0.60 and for the corresponding texture 5 - zero case it is 0.31 - 0.59.
Further our calculations reveal a crucial dependence of sin2$\beta$ on light
quark masses as well as the phase in this sector.

</DOC>
<DOC>
<DOCNO> 71670 </DOCNO>
Low Mass Dileptons from Pb+Au Collisions at CERN SPS


  We show that the dilepton spectra measured by the CERES collaboration in Pb +
Au interactions for various charge multiplicities can be reproduced by a
hadronic initial state with reduction in the masses of the vector mesons in the
thermal bath. Though such an effect may also be achieved by a large broadening
of the spectral function we show that the photon spectra is insensitive to
this. It is found that for higher multiplicities a good description of the data
can also be obtained with quark gluon plasma initial state if the reduction of
the vector meson masses in the mixed and hadronic phases is taken into account.
We observe that a thermal source with initial temperature ~ 200 MeV can
reproduce the observed enhancement in the low mass region of the dilepton
spectra. It is not possible to state which one of the two initial states (QGP
or hadronic) is compatible with the data. These findings are in agreement with
our earlier results obtained from the analysis of the WA98 photon spectra. We
estimate the number of pion-pion collisions near the rho-peak of the dilepton
spectra and argue that thermal equilibrium may have been achieved in the
system, justifying the use of hydrodynamical model to describe the space time
evolution.

</DOC>
<DOC>
<DOCNO> 68480 </DOCNO>
Realistic Calculation of the hep Astrophysical Factor


  The astrophysical factor for the proton weak capture on 3He is calculated
with correlated-hyperspherical-harmonics bound and continuum wave functions
corresponding to a realistic Hamiltonian consisting of the Argonne v18
two-nucleon and Urbana-IX three-nucleon interactions. The nuclear weak charge
and current operators have vector and axial-vector components, that include
one- and many-body terms. All possible multipole transitions connecting any of
the p-3He S- and P-wave channels to the 4He bound state are considered. The
S-factor at a p-3He center-of-mass energy of 10 keV, close to the Gamow-peak
energy, is predicted to be 10.1 10^{-20} keV b, a factor of five larger than
the standard-solar-model value. The P-wave transitions are found to be
important, contributing about 40 % of the calculated S-factor.

</DOC>
<DOC>
<DOCNO> 152072 </DOCNO>
Instantons in 4-dimensional gauged O(5) Skyrme models


  We consider a family of four-dimensional non-linear sigma models based on an
O(5) symmetric group, whose fields take their values on the 4-sphere S4. An
SO(4)-subgroup of the model is gauged. The solutions of the model are
characterised by two distinct topological charges, the Chern-Pontryagin charge
of the gauge field and the degree of the map, i.e. the winding number, of the
S4 field. The one dimensional equations arising from the variation of the
action density subjected to spherical symmetry are integrated numerically.
Several properties of the solutions thus constructed are pointed out. The only
solution with unit Chern-Pontryagin charge are the usual BPST instantons with
zero S4 winding number, while solutions with unit S4 winding number have zero
Chern-Pontryagin charge.

</DOC>
<DOC>
<DOCNO> 151700 </DOCNO>
Some exact results for the three-layer Zamolodchikov model


  In this paper we continue the study of the three-layer Zamolodchikov model
started in our previous works. We analyse numerically the solutions to the
Bethe ansatz equations. We consider two regimes I and II which differ by the
signs of the spherical sides (a1,a2,a3)->(-a1,-a2,-a3). We accept the two-line
hypothesis for the regime I and the one-line hypothesis for the regime II. In
the thermodynamic limit we derive integral equations for distribution densities
and solve them exactly. We calculate the partition function for the three-layer
Zamolodchikov model and check a compatibility of this result with the
functional relations. We also do some numerical checkings of our results.

</DOC>
<DOC>
<DOCNO> 151445 </DOCNO>
Scattering of relativistic particles with Aharonov-Bohm-Coulomb


  The Aharonov-Bohm-Coulomb potentials in two dimensions may describe the
interaction between two particles carrying electric charge and magnetic flux,
say, Chern--Simons solitons, or so called anyons. The scattering problem for
such two-body systems is extended to the relativistic case, and the scattering
amplitude is obtained as a partial wave series. The electric charge and
magnetic flux is ($-q$, $-\phi/Z$) for one particle and ($Zq$, $\phi$) for the
other. When $(Zq^2/\hbar c)^2\ll 1$, and $q\phi/2\pi\hbar c$ takes on integer
or half integer values, the partial wave series is summed up approximately to
give a closed form. The results exhibit some nonperturbative features and
cannot be obtained from perturbative quantum electrodynamics at the tree level.

</DOC>
<DOC>
<DOCNO> 116385 </DOCNO>
A New Hypothesis for Layers of High Reflectivity Seen in MST Radar


  Analysis of MST radar observations at Gadanki (near Tirupati, India), for a
period of 14 months from 1995 September to 1996 November, shows that "Clear air
Turbulence" is not the primary source of high MST radar reflectivity; this
conventional idea needs to be modified. An alternative hypothesis based on the
microphysics and microdynamics associated with aerosols and water substance in
the atmosphere, is presented here.

</DOC>
<DOC>
<DOCNO> 170175 </DOCNO>
Weyl-Wigner-Moyal formulation of a Dirac quantized constrained system


  An extension of the Weyl-Wigner-Moyal formulation of quantum mechanics
suitable for a Dirac quantized constrained system is proposed. In this
formulation, quantum observables are described by equivalent classes of Weyl
symbols. The Weyl product of these equivalent classes is defined. The new Moyal
bracket is shown to be compatible with the Dirac bracket for constrained
systems.

</DOC>
<DOC>
<DOCNO> 13151 </DOCNO>
Relaxation of 2+1 dimensional classical O(2) symmetric scalar fields


  Real time thermalization and relaxation phenomena are studied in the low
energy density phase of the 2+1 dimensional classical O(2) symmetric scalar
theory by solving numerically its dynamics. The near-equilibrium decay rate of
on-shell waves and the power law governing the large time asymptotics of the
off-shell relaxation agree with the analytic results based on linear response
theory. The realisation of the Mermin-Wagner theorem is also studied in the
final equilibrium ensemble.

</DOC>
<DOC>
<DOCNO> 10073 </DOCNO>
Metallic nanowires: multi-shelled or filled ?


  The room temperature structure of aluminum, copper and gold infinite
nanowires is studied. The molecular dynamics simulation method and the same
type of the embedded atom potentials made by Voter and coworkers are used. It
was found that multi-shelled and various filled metallic nanowires exist
depending on the metal and the initial configuration. The results were compared
with previous simulations for gold nanowires using different type of the
potential.

</DOC>
<DOC>
<DOCNO> 151573 </DOCNO>
What Can We Learn from QED at Large Couplings?


  In order to understand QCD at the energies relevant to hadronic physics one
requires analytical methods for dealing with relativistic gauge field theories
at large couplings. Strongly coupled quenched QED provides an ideal laboratory
for the development of such techniques, in particular as many calculations
suggest that - like QCD - this theory has a phase with broken chiral symmetry.
In this talk we report on a nonperturbative variational calculation of the
electron propagator within quenched QED and compare results to those obtained
in other approaches. We find surprising differences among these results.

</DOC>
<DOC>
<DOCNO> 9293 </DOCNO>
Tuning the trip to KPZ asymptopia


  Because of a close blood relationship between directed percolation & directed
polymers in random media, the latter's journey to asymptotic scaling can be
greatly retarded by an uninformed choice of departure point; i.e., the
bare-bond PDF employed in the transfer matrix study. Bisecting a gaussian noise
distribution, examining DPRM scaling for left & right halves separately, and
comparing results against the full PDF, reveals in the simplest possible manner
the essence of this dilemma. Paradoxically, when the bare-bond PDF possesses a
relative shortage [left demi-gaussian], rather than abundance [right
demi-gaussian] of low energy bonds, much better scaling is achieved. This
finding is somewhat counterintuitive since a zero-temperature DPRM seeks the
globally minimal path through a random energy landscape. Nevertheless, the
behavior is easily traced to the strong influence of the neighboring DP fixed
point function.
  This note communicates, in part, unpublished work referenced in Phys. Rev.
E58, R4096 (1998). We discovered, as well, that the RG road to asymptopia can
be highly refined by bootstrapping the presumed universal distribution from the
getgo...

</DOC>
<DOC>
<DOCNO> 12292 </DOCNO>
Comment on the paper ``Decoherence and the theory of continuous quantum


  In quant-ph/9812017v2 M.B. Mensky reviewed our application of the restricted
path integral approach to quantum measurements of energy. In this comment we
point out that Mensky's assessment of our results is incorrect.

</DOC>
<DOC>
<DOCNO> 69856 </DOCNO>
Low-Scale Axion from Large Extra Dimensions


  The mass of the axion and its decay rate are known to depend only on the
scale of Peccei-Quinn symmetry breaking, which is constrained by astrophysics
and cosmology to be between $10^9$ and $10^{12}$ GeV. We propose a new
mechanism such that this effective scale is preserved and yet the fundamental
breaking scale of $U(1)_{PQ}$ is very small (a kind of inverse seesaw) in the
context of large extra dimensions with an anomalous U(1) gauge symmetry in our
brane. Unlike any other (invisible) axion model, there are now possible
collider signatures in this scenario.

</DOC>
<DOC>
<DOCNO> 71361 </DOCNO>
A unique parametrization of the shapes of secondary dilepton spectra


  A unique parametrization of secondary (thermal) dilepton yields in heavy-ion
experiments at CERN-SPS is proposed. This parametrization resembles a thermal
$q \bar q$ annihilation rate. This is inspired by the observation that lepton
pair production rates are quantitatively similar, whether expressed in a
hadronic or partonic basis. Adding the thermal yield and the background
contributions (hadronic cocktail, Drell-Yan, correlated semileptonic decays of
open charm) the spectral shapes of the CERES/NA45, NA38, NA50 and HELIOS/3 data
from experiments with lead and sulfur beams can be well described.

</DOC>
<DOC>
<DOCNO> 13439 </DOCNO>
Etching of random solids: hardening dynamics and self-organized


  When a finite volume of an etching solution comes in contact with a
disordered solid, a complex dynamics of the solid-solution interface develops.
Since only the weak parts are corroded, the solid surface hardens
progressively. If the etchant is consumed in the chemical reaction, the
corrosion dynamics slows down and stops spontaneously leaving a fractal solid
surface, which reveals the latent percolation criticality hidden in any random
system. Here we introduce and study, both analytically and numerically, a
simple model for this phenomenon. In this way we obtain a detailed description
of the process in terms of percolation theory. In particular we explain the
mechanism of hardening of the surface and connect it to Gradient Percolation.

</DOC>
<DOC>
<DOCNO> 117846 </DOCNO>
Structure and Evolution of Circumstellar Disks Around Young Stars: New


  A question central to understanding the origin of our solar system is: how do
planets form in circumstellar disks around young stars? Because of the complex
nature of the physical processes involved, multi-wavelength observations of
large samples will be required in order to obtain a complete answer to this
question. Surveys undertaken with ISO have helped to solve pieces of this
puzzle in addition to uncovering new mysteries. We review a variety of studies
aimed at understanding; i) the physical structure and composition of
circumstellar disks commonly found surrounding young stellar objects; and ii)
the evolution of circumstellar disks from the active accretion phase to
post-planet building debris disks.

</DOC>
<DOC>
<DOCNO> 151765 </DOCNO>
Supergravity and "New" Six-Dimensional Gauge Theories


  In the first part of this letter, we analyse the supergravity dual
descriptions of six-dimensional field theories realized on the worldvolume of
(p,q) five-branes (OD5 theory). We show that in order for the low-energy gauge
theory description to be valid the theta parameter must be rational. Irrational
values of theta require a strongly coupled string description of the system at
low-energy. We discuss the phase structure and deduce some properties of these
theories. In the second part we construct and study the supergravity
description of NS5-branes with two electric RR field, which provides a dual
description of six-dimensional theories with several light open D-brane
excitations.

</DOC>
<DOC>
<DOCNO> 84545 </DOCNO>
Infinite hierarchies of exact solutions of the Einstein and


  For space-times with two spacelike isometries, we present infinite
hierarchies of exact solutions of the Einstein and Einstein--Maxwell equations
as represented by their Ernst potentials. This hierarchy contains three
arbitrary rational functions of an auxiliary complex parameter. They are
constructed using the so called `monodromy transform' approach and our new
method for the solution of the linear singular integral equation form of the
reduced Einstein equations. The solutions presented, which describe
inhomogeneous cosmological models or gravitational and electromagnetic waves
and their interactions, include a number of important known solutions as
particular cases.

</DOC>
<DOC>
<DOCNO> 11022 </DOCNO>
Regular and Anomalous Quantum Diffusion in the Fibonacci Kicked Rotator


  We study the dynamics of a quantum rotator kicked according to the
almost-periodic Fibonacci sequence. A special numerical technique allows us to
carry on this investigation for as many as $10^{12}$ kicks. It is shown that
above a critical kick strength the excitation of the system is well described
by regular diffusion, while below this border it becomes anomalous, and
sub-diffusive. A law for the dependence of the exponent of anomalous
sub-diffusion on the system parameters is established numerically. The analogy
between these results and quantum diffusion in models of quasi-crystal and in
the kicked Harper system is discussed.

</DOC>
<DOC>
<DOCNO> 178964 </DOCNO>
Peripheral Collisions of Relativistic Heavy Ions


  The physics of peripheral collisions with relativistic heavy ions (PCRHI) is
reviewed. One- and two-photon processes are discussed.

</DOC>
<DOC>
<DOCNO> 83448 </DOCNO>
Tree-gram Parsing: Lexical Dependencies and Structural Relations


  This paper explores the kinds of probabilistic relations that are important
in syntactic disambiguation. It proposes that two widely used kinds of
relations, lexical dependencies and structural relations, have complementary
disambiguation capabilities. It presents a new model based on structural
relations, the Tree-gram model, and reports experiments showing that structural
relations should benefit from enrichment by lexical dependencies.

</DOC>
<DOC>
<DOCNO> 70577 </DOCNO>
The resummed quark form factor in dimensional regularization


  The resummed expression for the quark form factor illustrates the fact that
dimensional continuation provides a regularization not only for ultraviolet and
infrared singularities of fixed order QCD amplitudes, but also for the Landau
pole arising in resummed calculations. Explicit renormalization group invariant
analytic expressions for the logarithm of the form factor are given up to
two-loop order in the QCD beta function.

</DOC>
<DOC>
<DOCNO> 12022 </DOCNO>
Localization Transition in Incommensurate non-Hermitian Systems


  A class of one-dimensional lattice models with incommensurate complex
potential $V(\theta)=2[\lambda_r cos(\theta)+i \lambda_i sin(\theta)]$ is found
to exhibit localization transition at $|\lambda_r|+|\lambda_i|=1$. This
transition from extended to localized states manifests in the behavior of the
complex eigenspectum. In the extended phase, states with real eigenenergies
have finite measure and this measure goes to zero in the localized phase.
Furthermore, all extended states exhibit real spectrum provided $|\lambda_r|
\ge |\lambda_i|$. Another novel feature of the system is the fact that the
imaginary part of the spectrum is sensitive to the boundary conditions {\it
only at the onset to localization}.

</DOC>
<DOC>
<DOCNO> 119084 </DOCNO>
VLT observations of GRS 1915+105


  We present near infrared spectroscopy of the superluminal microquasar \grs\
obtained with the first unit of the VLT (Based on observations collected at the
European Southern Observatory, Chile (ESO No 63.H-0261).) and the ISAAC
spectro-imager. The emission features detected in the VLT data have been
identified as He I, Br $\gamma$, He II and Na I. The detection of Na I is
reported here for the first time, while our confirmation of weak He II emission
provides support to previous marginal detections of this feature. By comparing
the observed spectra with those of massive stars, we find that our results are
very consistent with \grs being a high mass X-ray system with an early type
primary, as previously proposed by Chaty et al. (1996) and Mirabel et al.
(1997). The VLT spectra also provide evidence of P Cygni profiles, that turn
into blue emission wings when the system is in outburst. This observed line
profile evolution implies that \grs must be surrounded by an expanding
envelope, that is partially blown out during the X-ray outbursts. The presence
of such circumstellar gaseous material around \grs is more naturally understood
in the context of a massive luminous star than if the system was a low-mass
X-ray binary.

</DOC>
<DOC>
<DOCNO> 83084 </DOCNO>
Syntactic Autonomy: Why There is no Autonomy without Symbols and How


  Two different types of agency are discussed based on dynamically coherent and
incoherent couplings with an environment respectively. I propose that until a
private syntax (syntactic autonomy) is discovered by dynamically coherent
agents, there are no significant or interesting types of closure or autonomy.
When syntactic autonomy is established, then, because of a process of
description-based selected self-organization, open-ended evolution is enabled.
At this stage, agents depend, in addition to dynamics, on localized, symbolic
memory, thus adding a level of dynamical incoherence to their interaction with
the environment. Furthermore, it is the appearance of syntactic autonomy which
enables much more interesting types of closures amongst agents which share the
same syntax. To investigate how we can study the emergence of syntax from
dynamical systems, experiments with cellular automata leading to emergent
computation to solve non-trivial tasks are discussed. RNA editing is also
mentioned as a process that may have been used to obtain a primordial
biological code necessary open-ended evolution.

</DOC>
<DOC>
<DOCNO> 68712 </DOCNO>
New RG-invariants of Soft Supersymmetry Breaking Parameters


  We study new renormalization-group invariant quantities of soft supersymmetry
breaking parameters other than the ratio of gaugino mass to gauge coupling
squared by using the spurion method. The obtained invariants are useful to
probe supersymmetry breaking and mu-term generation mechanisms at high-energy
scale. We also discuss the convergence behavior of fixed points of
supersymmetry breaking parameters.

</DOC>
<DOC>
<DOCNO> 101055 </DOCNO>
The Koszul complex in projective dimension one


  Let $R$ be a noetherian ring and $M$ a finite $R$-module. With a linear form
$\chi$ on $M$ one associates the Koszul complex $K(\chi)$. If $M$ is a free
module, then the homology of $K(\chi)$ is well-understood, and in particular it
is grade sensitive with respect to $\Im\chi$.
  In this note we investigate the case of a module $M$ of projective dimension
1 (more precisely, $M$ has a free resolution of length 1) for which the first
non-vanishing Fitting ideal $\I_M$ has the maximally possible grade $r+1$,
$r=\rank M$. Then $h=\grade \Im\chi\le r+1$ for all linear forms $\chi$ on $M$,
and it turns out that $H_{r-i}(K(\chi))=0$ for all even $i<h$ and
$H_{r-i}(K(\chi))\iso \SS^{(i-1)/2}(C)$ for all odd $i<h$ where $\SS$ denotes
symmetric power and $C=\Ext_R^1(M,R)$, in other words, $C=\Cok\psi^*$ for a
presentation $$ 0\to F\stackrel{\psi}{\to} G \to M\to 0. $$ Moreover, if $h\le
r$, then $H_{r-h}(K(\chi))$ is neither 0 nor isomorphic to a symmetric power of
$C$, so that it is justified to say that $K(\chi)$ is grade sensitive for the
modules $M$ under consideration.
  We furthermore show that the maximally possible value $\grade \Im\chi=r+1$
can only occur in two extreme cases: (i) $r=1$ or (ii) $\rank F=1$ and $r$ is
odd.

</DOC>
<DOC>
<DOCNO> 170033 </DOCNO>
Molecular photon echoes as a signature of vibrational cat states


  Quantum interference between two distinct vibrational trajectories induced by
two pulse femtosecond excitation in molecules is shown to result in a photon
echo, providing direct evidence of the cat state superposition of Gaussian
vibrational wavepackets.

</DOC>
<DOC>
<DOCNO> 70018 </DOCNO>
Complete fermionic two-loop results for the M_W-M_Z interdependence


  The complete fermionic two-loop contributions to the prediction for the
W-boson mass from muon decay in the electroweak Standard Model are evaluated
exactly, i.e. no expansion in the top-quark and the Higgs-boson mass is made.
The result for the W-boson mass is compared with the previous result of an
expansion up to next-to-leading order in the top-quark mass. The predictions
are found to agree with each other within about 4 MeV. A simple
parameterization of the new result is presented, approximating the full result
better than 0.4 MeV for M_H < 1 TeV.

</DOC>
<DOC>
<DOCNO> 85271 </DOCNO>
On the use of algebraic programming in the general relativity


  This is a review devoted to some results of Algebraic Programming (Computer
Algebra) used in treating several problems of general relativity, based mainly
on already published articles. The article contains the talk given by the
author at The Albert Einstein Institut, Max Planck Institut fur
Gravitationstheorie, Golm, Germany, september 2000

</DOC>
<DOC>
<DOCNO> 69073 </DOCNO>
Finite Temperature and Large Gauge Invariance


  We discuss the problem of large gauge invariance at finite temperature.

</DOC>
<DOC>
<DOCNO> 119784 </DOCNO>
The (anti)correlation of the sub-mm and X-ray background sources


  The connection between the sub-mm and the hard X-ray backgrounds is studied
by comparing data at 2-10 keV and at 850um for a sample of 34 sources at fluxes
(or limiting fluxes) which resolve most of the background in the two bands.
These data were obtained with new SCUBA observations and by correlating data
sets available from the literature. None of the 11 hard X-ray (2-10 keV)
sources has a counterpart at 850um, with the exception of a faint Chandra
source, which is a candidate type 2 QSO at high redshift. These data indicate
that 2-10 keV sources brighter than 10^-15 erg s-1 cm-2, which make at least
75% of the background in this band, contribute for less than 7% to the
submillimetric background. Out of the 24 SCUBA sources 23 are undetected by
Chandra. These data indicate that most of these SCUBA sources must be powered
either by starburst activity, or by an AGN which is obscured by a column Nh >
10^25 cm-2, with a reflection efficiency in the hard X-rays significantly lower
than 1% in most cases.

</DOC>
<DOC>
<DOCNO> 13537 </DOCNO>
Comment on 'A new method to calculate the spin-glass order parameter of


  Contrary to the suggestion of Kitatani and Sinada (2000 J. Phys. A: Math.
Gen. {\bf 33} 3545-3553), the scaling analysis of the order parameter
distributions suggests the existence of a finite-temperature spin-glass phase
transition $T_c\ne 0$, even if the corrections to scaling are taken into
account.

</DOC>
<DOC>
<DOCNO> 7743 </DOCNO>
Macroscopic Quantum Phase Interference in Antiferromagnetic Particles


  The tunnel splitting in biaxial antiferromagnetic particles is studied with a
magnetic field applied along the hard anisotropy axis. We observe the
oscillation of tunnel splitting as a function of the magnetic field due to the
quantum phase interference of two tunneling paths of opposite windings. The
oscillation is similar to the recent experimental result with Fe}$_8$\textrm{\
molecular clusters.}

</DOC>
<DOC>
<DOCNO> 71893 </DOCNO>
Brane Quintessence


  We propose a new quintessence scenario in the brane cosmology, assuming that
a quintessence field $Q$ is confined in our 3-dimensional brane world. With a
potential $V(Q)= \mu^{\alpha+4} Q^{-\alpha}~(\alpha\geq 2)$, we find that the
density parameter of the scalar field decreases as $\Omega_Q \sim
a^{-4(\alpha-2)/(\alpha+2)}$ in the epoch of quadratic energy density
dominance, if $\alpha\leq 6$. This attractor solution is followed by the usual
tracking quintessence scenario after a conventional Friedmann universe is
recovered. With an equipartition of initial energy density, we find a natural
and successful quintessence model for $\alpha\gsim 4$.

</DOC>
<DOC>
<DOCNO> 8034 </DOCNO>
Elastic moduli, dislocation core energy and melting of hard disks in two


  Elastic moduli and dislocation core energy of the triangular solid of hard
disks of diameter $\sigma$ are obtained in the limit of vanishing dislocation-
antidislocation pair density, from Monte Carlo simulations which incorporates a
constraint, namely that all moves altering the local connectivity away from
that of the ideal triangular lattice are rejected. In this limit, we show that
the solid is stable against all other fluctuations at least upto densities as
low as $\rho \sigma^2 = 0.88$. Our system does not show any phase transition so
diverging correlation lengths leading to finite size effects and slow
relaxations do not exist. The dislocation pair formation probability is
estimated from the fraction of moves rejected due to the constraint which
yields, in turn, the core energy E_c and the (bare) dislocation fugacity y.
Using these quantities, we check the relative validity of first order and
Kosterlitz-Thouless-Halperin-Nelson-Young (KTHNY) melting scenarios and obtain
numerical estimates of the typical expected transition densities and pressures.
We conclude that a KTHNY transition from the solid to a hexatic phase preempts
the solid to liquid first order transition in this system albeit by a very
small margin, easily masked by crossover effects in unconstrained
``brute-force'' simulations with small number of particles.

</DOC>
<DOC>
<DOCNO> 102744 </DOCNO>
Separation of variables in perturbed cylinders


  We study the Laplace operator subject to Dirichlet boundary conditions in a
two-dimensional domain that is one-to-one mapped onto a cylinder (rectangle or
infinite strip). As a result of this transformation the original eigenvalue
problem is reduced to an equivalent problem for an operator with variable
coefficients. Taking advantage of the simple geometry we separate variables by
means of the Fourier decomposition method. The ODE system obtained in this way
is then solved numerically yielding the eigenvalues of the operator. The same
approach allows us to find complex resonances arising in some non-compact
domains. We discuss numerical examples related to quantum waveguide problems.

</DOC>
<DOC>
<DOCNO> 121052 </DOCNO>
The Effects of Dust on the Spectral Energy Distributions of Star-Forming


  I review the effects of dust, both in absorption and in emission, on the
spectral energy distributions (SEDs) of Local star-forming galaxies. The energy
balance between the stellar light absorbed by dust at UV-optical-nearIR
wavelengths and the energy re-emitted by dust in the far infrared (FIR) shows
that the amount of dust extinction affecting the galaxy can be predicted with
simple prescriptions applied to the UV-optical data. The implications of these
results for high redshift galaxies are discussed. Arguments can be given to
support the view that Local starbursts are representative of high-redshift
(z>2), UV-detected, star-forming galaxies. If this is the case, the high
redshift FIR emission will be generally undetected in sub-mm surveys, unless
(1) the bolometric luminosity of the high-z galaxies is comparable to or larger
than that of Local ultraluminous FIR galaxies and (2) their FIR SED contains a
cool dust component.

</DOC>
<DOC>
<DOCNO> 102548 </DOCNO>
Birational Unboundedness of $\Bbb Q$-Fano threefolds


  In this paper, we prove that the family of $\Bbb Q$-Fano threefolds with
Picard number one is birationally unbounded.

</DOC>
<DOC>
<DOCNO> 121495 </DOCNO>
Imaging the secondary stars in cataclysmic variables


  The secondary, Roche-lobe filling stars in cataclysmic variables (CVs) are
key to our understanding of the origin, evolution and behaviour of this class
of interacting binary. We review the basic properties of the secondary stars in
CVs and the observational and analysis methods required to detect them. We then
describe the various astro-tomographic techniques which can be used to map the
surface intensity distribution of the secondary star, culminating in a detailed
explanation of Roche tomography. We conclude with a summary of the most
important results obtained to date and future prospects.

</DOC>
<DOC>
<DOCNO> 150720 </DOCNO>
Anomalous Interactions of Five Dimensional USp(2k) Gauge Theory


  We consider the five dimensional $USp(2k)$ gauge theory which consists of one
antisymmetric and $n_{f}$ fundamental hypermultiplets. This gauge theory is a
many-probe generalization of the SU(2) gauge theory in five dimensions
considered by Seiberg in the context of probing type I superstring by a
D4-brane. This gauge theory can also be obtained from the USp(2k) matrix model
by matrix T-dual transformations in the large k limit. We exhibit the anomalous
interaction associated with this five dimensional theory on the new phase,
where the vacuum expectation values (vevs) of the scalars belonging to the
antisymmetric hypermultiplet are also nonvanishing. On the Coulomb phase, the
anomalous interaction has been computed in [1, 2].

</DOC>
<DOC>
<DOCNO> 170369 </DOCNO>
Applications of Integrated Magnetic Microtraps


  Lithographically fabricated circuit patterns can provide magnetic guides and
microtraps for cold neutral atoms. By combining several such structures on the
same ceramic substrate, we have realized the first ``atom chips'' that permit
complex manipulations of ultracold trapped atoms or de Broglie wavepackets. We
show how to design magnetic potentials from simple conductor patterns and we
describe an efficient trap loading procedure in detail. Applying the design
guide, we describe some new microtrap potentials, including a trap which
reaches the Lamb-Dicke regime for rubidium atoms in all three dimensions, and a
rotatable Ioffe-Pritchard trap, which we also demonstrate experimentally.
Finally, we demonstrate a device allowing independent linear positioning of two
atomic clouds which are very tightly confined laterally. This device is well
suited for the study of one-dimensional collisions.

</DOC>
<DOC>
<DOCNO> 9360 </DOCNO>
Relaxation Processes in Administered-Rate Pricing


  We show how a novel application of the theory of anelasticity unifies the
observed dynamics and proposed models of administered-rate products. This
theory yields a straightforward approach to rate model construction that we
illustrate by simulating the observed relaxation dynamics of two administered
rate products. We also demonstrate how the use of this formalism leads to a
natural definition of market friction.

</DOC>
<DOC>
<DOCNO> 9021 </DOCNO>
SO(10) Unification of Color Superconductivity and Chiral Symmetry


  Motivated by the SO(5) theory of high-temperature superconductivity and
antiferromagnetism, we ask if an SO(10) theory unifies color superconductivity
and chiral symmetry breaking in QCD. The transition to the color
superconducting phase would then be analogous to a spin flop transition. While
the spin flop transition generically has a unified SO(3) description, the SO(5)
and SO(10) symmetric fixed points are unstable, at least in (4 - epsilon)
dimensions, and require the fine-tuning of one additional relevant parameter.
If QCD is near the SO(10) fixed point, it has interesting consequences for
heavy ion collisions and neutron stars.

</DOC>
<DOC>
<DOCNO> 80578 </DOCNO>
Topology in 2D CP**(N-1) models on the lattice: a critical comparison of


  Two-dimensional CP**(N-1) models are used to compare the behavior of
different cooling techniques on the lattice. Cooling is one of the most
frequently used tools to study on the lattice the topological properties of the
vacuum of a field theory. We show that different cooling methods behave in an
equivalent way. To see this we apply the cooling methods on classical
instantonic configurations and on configurations of the thermal equilibrium
ensemble. We also calculate the topological susceptibility by using the cooling
technique.

</DOC>
<DOC>
<DOCNO> 178735 </DOCNO>
Tilted Rotation and Wobbling Motion in Nuclei


  The self-consistent harmonic oscillator model including the three-dimensional
cranking term is extended to describe collective excitations in the random
phase approximation. It is found that quadrupole collective excitations
associated with wobbling motion in rotating nuclei lead to the appearance of
two- or three-dimensional rotation.

</DOC>
<DOC>
<DOCNO> 11175 </DOCNO>
Broken Generalized Kohn Theorem in Harmonic Dot Lattices due to Coulomb


  The Generalized Kohn Theorem in arrays of parabolic quantum dots with Coulomb
interaction between the dots is violated, if there are different dot species
involved. We solve the Schr\"odinger equation for cubic lattices with two
different dots per unit cell: i) two different circular dots and ii) two
elliptical dots, which are rotated by $90^o$ relative to each other. The
interaction between the dots is considered in dipole approximation and long--
wavelength excitation spectra including FIR intensities are calculated. The
energy spectrum of the first case can be expressed as a superposition of two
noninteracting dots with an effective confinement frequency, which includes the
effect of dot interaction. Only in the second case a splitting of degenerate
absorption lines (versus magnetic field) occurs, which is a qualitative
indication for interdot interaction. If the interaction becomes very strong and
if all lattice sites (not necessarily confinement potentials) are equivalent,
then the contribution of the dot interaction over-plays possible differences in
the confinement potentials and the Kohn Theorem gradually re-entries, in the
sense that one pair of excitation modes (pseudo Kohn modes) becomes independent
of the interaction strength.

</DOC>
<DOC>
<DOCNO> 152407 </DOCNO>
Nielsen-Olesen vortices in noncommutative space


  We construct an exact regular vortex solution to the self-dual equations of
the Abelian Higgs model in non-commutative space for arbitrary values of
$\theta$. To this end, we propose an ansatz which is the analogous, in Fock
space, to the one leading to exact solutions for the Nielsen-Olesen vortex in
commutative space. We compute the flux and energy of the solution and discuss
its relevant properties.

</DOC>
<DOC>
<DOCNO> 70474 </DOCNO>
Anomalous U(1)_A and Electroweak Symmetry Breaking


  We suggest a new mechanism for electroweak symmetry breaking in the
supersymmetric Standard Model. Our suggestion is based on the presence of an
anomalous U(1)_A gauge symmetry, which naturally arises in the four dimensional
superstring theory, and heavily relies on the value of the corresponding
Fayet-Illiopoulos \xi-term.

</DOC>
<DOC>
<DOCNO> 70678 </DOCNO>
Resonance Enhanced Tunneling


  Time evolution of tunneling in thermal medium is examined using the real-time
semiclassical formalism previously developed. Effect of anharmonic terms in the
potential well is shown to give a new mechanism of resonance enhanced
tunneling. If the friction from environment is small enough, this mechanism may
give a very large enhancement for the tunneling rate. The case of the
asymmetric wine bottle potential is worked out in detail.

</DOC>
<DOC>
<DOCNO> 8772 </DOCNO>
Quenched Spin Tunneling and Diabolical Points in Magnetic Molecules: I.


  The perfect quenching of spin tunneling that has previously been discussed in
terms of interfering instantons, and has recently been observed in the magnetic
molecule \Fe8, is treated using a discrete phase integral (or
Wentzel-Kramers-Brillouin) method. The simplest model Hamiltonian for the
phenomenon leads to a Schr\"odinger equation that is a five-term recursion
relation. This recursion relation is reflection-symmetric when the magnetic
field applied to the molecule is along the hard magnetic axis. A completely
general Herring formula for the tunnel splittings for all reflection-symmetric
five-term recursion relations is obtained. Using connection formulas for a new
type of turning point that may be described as lying "under the barrier", and
which underlies the oscillations in the splitting as a function of magnetic
field, this Herring formula is transformed into two other formulas that express
the splittings in terms of a small number of action and action-like integrals.
These latter formulas appear to be generally valid, even for problems where the
recursion contains more than five terms. The results for the model Hamiltonian
are compared with experiment, numerics, previous instanton based approaches,
and the limiting case of no magnetic field.

</DOC>
<DOC>
<DOCNO> 69823 </DOCNO>
Slow-roll inflation and CMB anisotropy data


  We emphasize that the estimation of cosmological parameters from cosmic
microwave background (CMB) anisotropy data, such as the recent high resolution
maps from BOOMERanG and MAXIMA-1, requires assumptions about the primordial
spectra. The latter are predicted from inflation. The physically best-motivated
scenario is that of slow-roll inflation. However, very often, the unphysical
power-law inflation scenario is (implicitly) assumed in the CMB data analysis.
We show that the predicted multipole moments differ significantly in both
cases. We identify several misconceptions present in the literature (and in the
way inflationary relations are often combined in popular numerical codes). For
example, we do not believe that, generically, inflation predicts the relation
n_S - 1 = n_T for the spectral indices of scalar and tensor perturbations or
that gravitational waves are negligible. We calculate the CMB multipole moments
for various values of the slow-roll parameters and demonstrate that an
important part of the space of parameters (n_S, n_T) has been overlooked in the
CMB data analysis so far.

</DOC>
<DOC>
<DOCNO> 121205 </DOCNO>
The near-infrared view of SBS 0335-052


  We present near-infrared (NIR) spectra, deep J, H and K low-resolution ima
ges, and high-resolution images in J and Ks of the low-metallicity blue dwarf
gal axy SBS 0335-052. These new NIR data, together with optical and
mid-infrared data from the literature, are used to constrain the properties and
the star formation history of the galaxy. The NIR spectral characteristics and
broadband colors of this galaxy are those of an extremely young starburst. We
find that the NIR emission is dominated by star formation occuring in clusters
younger than 5 Myr; no optically hidden star formation is revealed in our data.
We also find that a warm-dust component is necessary to explain the H-K color,
and is consistent with the mid-infrared spectral energy distribution. Finally,
we quantify the possible contribution from an evolved stellar populatio n.

</DOC>
<DOC>
<DOCNO> 122439 </DOCNO>
Clustering of Very Red Galaxies in the Las Campanas IR Survey


  We report results from the first 1000 square arc-minutes of the Las Campanas
IR survey. We have imaged 1 square degree of high latitude sky in six distinct
fields to a 5-sigma H-band depth of 20.5 (Vega). Optical imaging in the
V,R,I,and z' bands allow us to select color subsets and
photometric-redshift-defined shells. We show that the angular clustering of
faint red galaxies (18 < H < 20.5, I - H > 3) is an order of magnitude stronger
than that of the complete H-selected field sample. We employ three approaches
to estimate $n(z)$ in order to invert w(theta) to derive r_0. We find that our
n(z) is well described by a Gaussian with <z> = 1.2, sigma(z) = 0.15. From this
we derive a value for r_0 of 7 (+2,-1) co-moving H^{-1} Mpc at <z> = 1.2. This
is a factor of ~ 2 larger than the clustering length for Lyman break galaxies
and is similar to the expectation for early type galaxies at this epoch.

</DOC>
<DOC>
<DOCNO> 117427 </DOCNO>
A model-independent analysis of the variability of GRS 1915+105


  We analyzed 163 observations of the microquasar GRS 1915+105 made with the
Rossi X-ray Timing Explorer (RXTE) in the period 1996-1997. For each
observation, we produced light curves and color-color diagrams. We classified
the observations in 12 separate classes, based on their count rate and color
characteristics. From the analysis of these classes, we reduced the variability
of the source to transitions between three basic states: a hard state
corresponding to the non-observability of the innermost parts of the accretion
disk, and two softer states with a fully observable disk. These two soft states
represent different temperatures of the accretion disk, related to different
local values of the accretion rate. The transitions between these states can be
extremely fast. The source moves between these three states following certain
patterns and avoiding others, giving rise to a relatively large but limited
number of variability classes. These results are the first step towards a
linking of the properties of this exceptional source with standard black-hole
systems and with accretion disk models.

</DOC>
<DOC>
<DOCNO> 8501 </DOCNO>
Production Of Multiple 87Rb Condensates And Atom Lasers By Rf Coupling


  We have investigated the rf output coupling of a 87Rb condensate from a
Ioffe-Pritchard magnetic trap. Multiple condensates in different Zeeman states
are produced, their population being varied by playing with the duration and
the amplitude of the rf pulse. Both pulsed and continuous outputs (atom laser)
have been observed.

</DOC>
<DOC>
<DOCNO> 119758 </DOCNO>
Asteroids in the Inner Solar System II - Observable Properties


  This paper presents synthetic observations of long-lived, coorbiting
asteroids of Mercury, Venus, the Earth and Mars. Our sample is constructed by
taking the limiting semimajor axes, differential longitudes and inclinations
for long-lived stability provided by simulations. The intervals are randomly
populated with values to create initial conditions. These orbits are
re-simulated to check that they are stable and then re-sampled every 2.5 years
for 1 million years. The Mercurian sample contains only horseshoe orbits, the
Martian sample only tadpoles. For both Venus and the Earth, the greatest
concentration of objects on the sky occurs close to the classical Lagrange
points at heliocentric ecliptic longitudes of 60 and 300 degrees. The
distributions are broad especially if horseshoes are present in the sample. The
full-width half maximum (FWHM) in heliocentric longitude for Venus is 325
degrees and for the Earth is 328 degrees. The mean and most common velocity of
these coorbiting satellites coincides with the mean motion of the parent
planet, but again the spread is wide with a FWHM for Venus of 27.8 arcsec/hr
and for the Earth of 21.0 arcsec/hr. For Mars, the greatest concentration on
the sky occurs at heliocentric ecliptic latitudes of 12 degrees. The peak of
the velocity distribution occurs at 65 arcsec/hr, significantly less than the
Martian mean motion, while its FWHM is 32.3 arcsec/hr. The case of Mercury is
the hardest of all, as the greatest concentration occurs at heliocentric
longitudes close to the Sun.

</DOC>
<DOC>
<DOCNO> 152023 </DOCNO>
Symmetry Breaking/Restoration in a Non-Simply Connected Space-Time


  Field theories compactified on non-simply connected spaces, which in general
allow to impose twisted boundary conditions, are found to unexpectedly have a
rich phase structure. One of characteristic features of such theories is the
appearance of critical radii, at which some of symmetries are broken/restored.
A phase transition can occur at the classical level, or can be caused by
quantum effects. The spontaneous breakdown of the translational invariance of
compactified spaces is another characteristic feature. As an illustrative
example,the O(N) $\phi^4$ model on $M^3\otimes S^1$ is studied and the novel
phase structure is revealed.

</DOC>
<DOC>
<DOCNO> 121269 </DOCNO>
Explaining the entropy excess in clusters and groups of galaxies without


  The X-ray luminosity and temperature of clusters and groups of galaxies do
not scale in a self-similar manner. This has often been interpreted as a sign
that the intracluster medium has been substantially heated by non-gravitational
sources. In this paper, we propose a simple model which, instead, uses the
properties of galaxy formation to explain the observations. Drawing on
available observations, we show that there is evidence that the efficiency of
galaxy formation was higher in groups than in clusters. If confirmed, this
would deplete the low-entropy gas in groups, increase their central entropy and
decrease their X-ray luminosity. A simple, empirical, hydrostatic model appears
to match both the luminosity-temperature relation of clusters and properties of
their internal structure as well.

</DOC>
<DOC>
<DOCNO> 122140 </DOCNO>
Identification of a complete sample of northern ROSAT All-sky survey


  In order to derive statistical properties of a complete X-ray selected sample
of AGN we used the classification spectra of the RASS Selected Areas-North
survey to study the luminosities, redshifts, X-ray/visual flux ratios, line
widths, and various correlations between observed parameters of all Seyfert
galaxies and QSOs in this sample. On the basis of these data we discuss
implications for the current AGN models.

</DOC>
<DOC>
<DOCNO> 11675 </DOCNO>
Electrically Tunable Collective Modes in a MEMS Resonator Array


  Using optical diffraction, we study the mechanical vibrations of an array of
micromechanical resonators. Implementing tunable electrostatic coupling between
the suspended, doubly-clamped Au beams leads to the formation of a band of
collective vibrational modes within these devices. The evolution of these modes
with coupling strength is clearly manifested in the optical diffraction pattern
of light transmitted through the array. The experimental results are analyzed
using a simple model for one-dimensional phonons. These structures offer unique
prospects for spectral analysis of complex mechanical stimuli.

</DOC>
<DOC>
<DOCNO> 120417 </DOCNO>
Multiwavelength optical observations of chromospherically active binary


  This is the third paper of a series aimed at studying the chromosphere of
active binary systems using the information provided for several optical
spectroscopic features. High resolution echelle spectra including all the
optical chromospheric activity indicators from the Ca II H & K to Ca II IRT
lines are analysed here for 16 systems. The chromospheric contribution in these
lines has been determined using the spectral subtraction technique. Very broad
wings have been found in the subtracted H_alpha profile of the very active star
HU Vir. These profiles are well matched using a two-component Gaussian fit
(narrow and broad) and the broad component can be interpreted as arising from
microflaring. Red-shifted absorption features in the H_alpha line have been
detected in several systems and excess emission in the blue wing of FG UMa was
also detected. These features indicate that several dynamical processes, or a
combination of them, may be involved. Using the E(H_alpha)/E(H_beta) ratio as a
diagnostic we have detected prominence-like extended material viewed off the
limb in many stars of the sample, and prominences viewed against the disk at
some orbital phases in the dwarfs OU Gem and BF Lyn. The He I D_3 line has been
detected as an absorption feature in mainly all the giants of the sample. Total
filling-in of the He I D_3, probably due to microflaring activity, is observed
in HU Vir. Self-absorption with red asymmetry is detected in the Ca II H & K
lines of the giants 12 Cam, FG UMa and BM CVn. All the stars analysed show
clear filled-in Ca II IRT lines or even notable emission reversal. The small
values of the E(8542)/E(8498) ratio we have found indicate Ca II IRT emission
arises from plage-like regions.

</DOC>
<DOC>
<DOCNO> 150814 </DOCNO>
Solitons and Domain Walls in Odd Dimensions


  We discuss the existance of smooth soliton solutions which interpolate
between supersymmetric vacua in odd-dimensional theories. In particular we
apply this analysis to a wide class of supergravities to argue against the
existence of smooth domain walls interpolating between supersymmetric vacua. We
find that if the superpotential changes sign then any Goldstino modes will
diverge.

</DOC>
<DOC>
<DOCNO> 10065 </DOCNO>
Massive skyrmions in quantum Hall ferromagnets


  We apply the theory of elasticity to study the effects of skyrmion mass on
lattice dynamics in quantum Hall systems. We find that massive Skyrme lattices
behave like a Wigner crystal in the presence of a uniform perpendicular
magnetic field. We make a comparison with the microscopic Hartree-Fock results
to characterize the mass of quantum Hall skyrmions at $\nu=1$ and investigate
how the low temperature phase of Skyrme lattices may be affected by the
skyrmion mass.

</DOC>
<DOC>
<DOCNO> 85425 </DOCNO>
On unbounded bodies with finite mass: asymptotic behaviour


  There is introduced a class of barotropic equations of state (EOS) which
become polytropic of index $n = 5$ at low pressure. One then studies
asymptotically flat solutions of the static Einstein equations coupled to
perfect fluids having such an EOS. It is shown that such solutions, in the same
manner as the vacuum ones, are conformally smooth or analytic at infinity, when
the EOS is smooth or analytic, respectively.

</DOC>
<DOC>
<DOCNO> 121284 </DOCNO>
The Bar Pattern Speed in NGC 7079


  We have used 2D Fabry-Perot absorption-line spectroscopy of the SB0 galaxy
NGC 7079 to measure its bar pattern speed, $\om$. As in all previous cases of
bar pattern speed measurements, we find a fast bar. We estimate that NGC 7079
has been undisturbed for at least the past Gyr or roughly 8 bar rotations, long
enough for the bar to have slowed down significantly through dynamical friction
if the disk is sub-maximal.

</DOC>
<DOC>
<DOCNO> 152184 </DOCNO>
Fluxons and Exact BPS Solitons in Non-Commutative Gauge Theory


  We show that the fluxon solution of the non-commutative gauge theory and its
variations are obtained by the soliton generation method recently given by J.
A. Harvey, P. Kraus and F. Larsen [hep-th/0010060]. Although this method
generally produces non-BPS solutions of equations of motion, the solutions we
obtained are BPS. We give the brane interpretation of these BPS solutions and
study their counterparts in the ordinary description by the Seiberg-Witten map.

</DOC>
<DOC>
<DOCNO> 68034 </DOCNO>
Compact Hyperbolic Extra Dimensions: Branes, Kaluza-Klein Modes and


  We reconsider theories with low gravitational (or string) scale M_* where
Newton's constant is generated via new large-volume spatial dimensions, while
Standard Model states are localized to a 3-brane. Utilizing compact hyperbolic
manifolds (CHM's) we show that the spectrum of Kaluza-Klein (KK) modes is
radically altered. This allows an early universe cosmology with normal
evolution up to substantial temperatures, and completely negates the
constraints on M_* arising from astrophysics. Furthermore, an exponential
hierarchy between the usual Planck scale and the true fundamental scale of
physics can emerge with only order unity coefficients. The linear size of the
internal space remains small. The proposal has striking testable signatures.

</DOC>
<DOC>
<DOCNO> 7701 </DOCNO>
Fluctuation dissipation ratio in the one dimensional kinetic Ising model


  The exact relation between the response function $R(t,t^{\prime})$ and the
two time correlation function $C(t,t^{\prime})$ is derived analytically in the
one dimensional kinetic Ising model subjected to a temperature quench. The
fluctuation dissipation ratio $X(t,t^{\prime})$ is found to depend on time
through $C(t,t^{\prime})$ in the time region where scaling $C(t,t^{\prime}) =
f(t/t^{\prime})$ holds. The crossover from the nontrivial form
$X(C(t,t^{\prime}))$ to $X(t,t^{\prime}) \equiv 1$ takes place as the waiting
time $t_w$ is increased from below to above the equilibration time $t_{eq}$.

</DOC>
<DOC>
<DOCNO> 102484 </DOCNO>
On the Topology of Fibrations with Section and Free Loop Spaces


  We relate the brace products of a fibration with section to the differentials
in its serre spectral sequence. In the particular case of free loop fibrations,
we establish a link between these differentials and browder operations in the
fiber. Applications and several calculations (for the particular case of
spheres and wedges of spheres) are given.

</DOC>
<DOC>
<DOCNO> 7723 </DOCNO>
A scalable solid-state quantum computer based on quantum dot pillar


  We investigate an optically driven quantum computer based on electric dipole
transitions within coupled single-electron quantum dots. Our quantum register
consists of a freestanding n-type pillar containing a series of pair wise
coupled asymmetric quantum dots, each with a slightly different energy
structure, and with grounding leads at the top and bottom of the pillar.
Asymmetric quantum wells confine electrons along the pillar axis and a
negatively biased gate wrapped around the center of the pillar allows for
electrostatic confinement in the radial direction. We self-consistently solve
coupled Schrodinger and Poisson equations and develop a design for a
three-qubit quantum register. Our results indicate that a single gate electrode
can be used to localize a single electron in each of the quantum dots. Adjacent
dots are strongly coupled by electric dipole-dipole interactions arising from
the dot asymmetry, thus enabling rapid computation rates. The dots are tailored
to minimize dephasing due to spontaneous emission and phonon scattering and to
maximize the number of computation cycles. The design is scalable to a large
number of qubits.

</DOC>
<DOC>
<DOCNO> 100548 </DOCNO>
Generalization of Wigner's unitary-antiunitary theorem for indefinite


  We present a generalization of Wigner's unitary-antiunitary theorem for pairs
of ray transformations. As a particular case, we get a new Wigner-type theorem
for non-Hermitian indefinite inner product spaces.

</DOC>
<DOC>
<DOCNO> 121604 </DOCNO>
Constrained Superconducting Membranes


  We present a geometrical canonical description for superconducting membranes.
We consider a general action which includes a general class of superconducting
extended objects (strings and domain walls). The description is inspired in the
ADM framework of general relativity but, instead of the standard canonical
variables a different kind of phase space is considered.
 The Poisson algebra of the constraints and the counting of degrees of freedom
is performed. The new description is illustrated considering a superconducting
domain wall on a curved background spacetime.

</DOC>
<DOC>
<DOCNO> 11016 </DOCNO>
Mesoscopic Ferromagnet/Superconductor Junctions and the Proximity Effect


  We have measured the electrical transport of submicron ferromagnets (Ni) in
contact with a mesoscopic superconductor (Al) for a range of interface
resistances. In the geometry measured, the interface and the ferromagnet are
measured separately. The ferromagnet itself shows no appreciable
superconducting proximity effect, but the ferromagnet/superconductor interface
exhibits strong temperature, field and current bias dependences. These effects
are dependent on the local magnetic field distribution near the interface
arising from the ferromagnet. We find that the temperature dependences may be
fit to a modified version of the Blonder-Tinkham-Klapwijk theory for
normal-superconductor transport.

</DOC>
<DOC>
<DOCNO> 85347 </DOCNO>
Nonminimal Scalar-Tensor Theories and Quantum Gravity


  Recentely, it is shown that the quantum effects of matter determine the
conformal degree of freedom of the space-time metric. This was done in the
framework of a scalar-tensor theory with one scalar field. A point with that
theory is that the form of quantum potential is preassumed. Here we present a
scalar-tensor theory with two scalar fields, and no assumption on the form of
quantum potential. It is shown that using the equations of motion one gets the
correct form of quantum potential plus some corrections.

</DOC>
<DOC>
<DOCNO> 11308 </DOCNO>
Fermi-Liquid Interactions in d-Wave Superconductor


  This article develops a quantitative quasiparticle model of the
low-temperature properties of d-wave superconductors which incorporates both
Fermi-liquid effects and band-structure effects. The Fermi-liquid interaction
effects are found to be classifiable into strong and negligible renormalizaton
effects, for symmetric and antisymmetric combinations of the energies of
$k\uparrow$ and $-k\downarrow$ quasiparticles, respectively. A particularly
important conclusion is that the leading clean-limit temperature-dependent
correction to the superfluid density is not renormalized by Fermi-liquid
interactions, but is subject to a Fermi velocity (or mass) renormalization
effect. This leads to difficulties in accounting for the penetration depth
measurements with physically acceptable parameters, and hence reopens the
question of the quantitative validity of the quasiparticle picture.

</DOC>
<DOC>
<DOCNO> 12207 </DOCNO>
Trajectories in phase diagrams, growth processes and computational


  Most decision and optimization problems encountered in practice fall into one
of two categories with respect to any particular solving method or algorithm:
either the problem is solved quickly (easy) or else demands an impractically
long computational effort (hard). Recent investigations on model classes of
problems have shown that some global parameters, such as the ratio between the
constraints to be satisfied and the adjustable variables, are good predictors
of problem hardness and, moreover, have an effect analogous to thermodynamical
parameters, e.g. temperature, in predicting phases in condensed matter physics
[Monasson et al., Nature 400 (1999) 133-137]. Here we show that changes in the
values of such parameters can be tracked during a run of the algorithm defining
a trajectory through the parameter space. Focusing on 3-Satisfiability, a
recognized representative of hard problems, we analyze trajectories generated
by search algorithms using growth processes statistical physics. These
trajectories can cross well defined phases, corresponding to domains of easy or
hard instances, and allow to successfully predict the times of resolution.

</DOC>
<DOC>
<DOCNO> 170644 </DOCNO>
Sharp Quantum vs. Classical Query Complexity Separations


  We obtain the strongest separation between quantum and classical query
complexity known to date -- specifically, we define a black-box problem that
requires exponentially many queries in the classical bounded-error case, but
can be solved exactly in the quantum case with a single query (and a polynomial
number of auxiliary operations). The problem is simple to define and the
quantum algorithm solving it is also simple when described in terms of certain
quantum Fourier transforms (QFTs) that have natural properties with respect to
the algebraic structures of finite fields. These QFTs may be of independent
interest, and we also investigate generalizations of them to noncommutative
finite rings.

</DOC>
<DOC>
<DOCNO> 12862 </DOCNO>
Spin and charge dynamics of the ferromagnetic and antiferromagnetic


  We present a detailed numerical study of spin and charge dynamics of the
two-dimensional Kondo lattice model with hopping t and exchange J. At T=0 and J
> 0, the competition between the RKKY interaction and Kondo effect triggers a
quantum phase transition between magnetically ordered and disordered
insulators: J_c/t = 1.45(5). The quasiparticle gap scales as |J|. S(q,\omega),
evolves smoothly from its strong coupling form with spin gap at q = (\pi,\pi)
to a spin wave form. At J>0, A(\vec{k},\omega) shows a dispersion relation
following that of hybridized bands. For J < J_c this feature is supplemented by
shadows thus pointing to a coexistence of Kondo screening and magnetism. For J
< 0 A(\vec{k},\omega) is similar to that of non-interacting electrons in a
staggered magnetic field. Spin, T_S, and charge, T_C, scales are defined. For
weak to intermediate couplings, T_S marks the onset of antiferromagnetic
fluctuations and follows a J^2 law. At strong couplings T_S scales as J. T_C
scales as J both at weak and strong couplings. At and slightly below T_C we
observe i) a rise in the resistivity as a function of decreasing temperature,
ii) a dip in the integrated density of states at the Fermi energy and iii) the
occurrence of hybridized bands in A(k,\omega). It is shown that in the weak
coupling limit, the charge gap of order J is of magnetic origin. The specific
heat shows a two peak structure, the low temperature peak being of magnetic
origin. Our results are compared to various mean-field theories.

</DOC>
<DOC>
<DOCNO> 39861 </DOCNO>
B decays at the LHC


  We review the prospects for B decay studies at the LHC. 

</DOC>
<DOC>
<DOCNO> 100977 </DOCNO>
A universal construction for moduli spaces of decorated vector bundles


  Let $X$ be a smooth projective curve over the complex numbers. To every
representation $\rho\colon \GL(r)\lra \GL(V)$ of the complex general linear
group on the finite dimensional complex vector space $V$ which satisfies the
assumption that there be an integer $\alpha$ with $\rho(z \id_{\C^r})=z^\alpha
\id_V$ for all $z\in\C^*$ we associate the problem of classifying triples
$(E,L,\phi)$ where $E$ is a vector bundle of rank $r$ on $X$, $L$ is a line
bundle on $X$, and $\phi\colon E_\rho\lra L$ is a non trivial homomorphism.
Here, $E_\rho$ is the vector bundle of rank $\dim V$ associated to $E$ via
$\rho$. If we take, for example, the standard representation of $\GL(r)$ on
$\C^r$ we have to classify triples $(E,L,\phi)$ consisting of $E$ as before and
a non-zero homomorphism $\phi\colon E\lra L$ which includes the so-called
Bradlow pairs. For the representation of $\GL(r)$ on $S^2\C^3$ we find the
conic bundles of Gomez and Sols. In the present paper, we will formulate a
general semistability concept for the above triples which depends on a rational
parameter $\delta$ and establish the existence of moduli spaces of
$\delta$-(semi)stable triples of fixed topological type. The notion of
semistability mimics the Hilbert-Mumford criterion for $SL(r)$ which is the
main reason that such a general approach becomes feasible. In the known
examples (the above, Higgs bundles, extension pairs, oriented framed bundles)
we show how to recover the "usual" semistability concept. This process of
simplification can also be formalized. Altogether, our results provide a
unifying construction for the moduli spaces of most decorated vector bundle
problems together with an automatism for finding the right notion of
semistability and should therefore be of some interest.

</DOC>
<DOC>
<DOCNO> 121980 </DOCNO>
The Complete Bispectrum of COBE-DMR Four Year Maps


  We extend a previous bispectrum analysis of the COBE-DMR 4 year maps,
allowing for the presence of correlations between all possible angular scales.
We find that the non-Gaussian signal found earlier for bispectrum components
including adjacent modes does not extend to triplets of modes with larger
separations. Indeed for all separations $\Delta\ell >1$ we find that the
COBE-DMR data is very Gaussian. The implication seems to be that the previously
detected non-Gaussian scale-scale correlation falls off very quickly with mode
separation.

</DOC>
<DOC>
<DOCNO> 11484 </DOCNO>
Evidence for small or intermediate-size polarons in the ferromagnetic


  Oxygen-isotope effects on the intrinsic resistivity have been studied in
high-quality epitaxial thin films of La_{0.75}Ca_{0.25}MnO_{3} and
Nd_{0.7}Sr_{0.3}MnO_{3}. We found that the residual resistivity \rho_{o}
increases by about 15(3)% upon replacing ^{16}O by ^{18}O. This provides strong
evidence for the presence of small or intermediate-size polarons in the
metallic ferromagnetic state. Furthermore, the temperature dependent part of
the resistivity at low temperatures consists of an AT^{4.5} term contributed
from 2-magnon scattering, and a B\omega_{s}/\sinh^{2}(\hbar\omega_{s}/2k_{B}T)
term which arises from scattering by a soft optical phonon mode. The absolute
magnitudes of the coefficient A and the phonon frequency \hbar\omega_{s} for
both isotope samples are in quantitative agreement with theoretical
predictions.

</DOC>
<DOC>
<DOCNO> 84434 </DOCNO>
A Class of Einstein-Maxwell Fields Generalizing the Equilibrium


  The Einstein-Maxwell fields of rotating stationary sources are represented by
the SU(2,1) spinor potential $\Psi_A$ satisfying \[ \nabla \cdot [\Theta
^{-1}(\Psi_A\nabla \Psi_B-\Psi_B\nabla \Psi_A)]=-2\Theta ^{-2}\vec{C}\cdot
(\Psi_A\nabla \Psi_B-\Psi_B\nabla \Psi_A) \] where $\Theta =\Psi ^{\dagger
}\cdot \Psi $ is the SU(2,1) norm of $\Psi $% . The Ernst potentials are
expressed in terms of the spinor potential by $% {\cal E}=\frac{\Psi_1-\Psi
_2}{\Psi_1+\Psi_2}$, $\Phi =\frac{\Psi_3}{% \Psi_1+\Psi_2}$ . The group
invariant vector $\vec{C}=-2i\func{Im}\{\Psi ^{\dagger}\cdot \nabla \Psi \}$ is
generated exclusively by the rotation of the source, hence it is appropriate to
refer to $\vec{C}$ as the {\em swirl} of the field. Static fields have no
swirl.
  The fields with no swirl are a class generalizing the equilibrium ($| e| =m$)
class of Einstein-Maxwell fields. We obtain the integrability conditions and a
highly symmetrical set of field equations for this class, as well as exact
solutions and an open research problem.

</DOC>
<DOC>
<DOCNO> 169843 </DOCNO>
Reply to Comment by A. Moroz


  In (quant-ph/9911099 version 1) A. Moroz claims that the exponent $\eta$ from
the local photon density of states near a band gap edge $\rho(\omega) =
K(\vec{r}) |\omega_c - \omega|^\eta$ varies strongly with the position in the
crystal. We show that this is not the case and we demonstrate the error in his
analysis.

</DOC>
<DOC>
<DOCNO> 120178 </DOCNO>
ISO deep far-infrared survey in the "Lockman Hole" II. Power spectrum


  We investigate the characteristics of FIR brightness fluctuations at 90
micron and 170 micron in the Lockman Hole, which were surveyed with ISOPHOT
aboard the Infrared Space Observatory(ISO). We first calculated the angular
correlation function of each field and then its Fourier transform(the angular
Power Spectral Density: PSD) over the spatial frequency range of f=0.05 - 1
arcmin^-1. The PSDs are found to be rather flat at low spatial frequencies (f
<= 0.1 arcmin^-1), slowly decreasing toward higher frequencies. These spectra
are unlike the power-law ones seen in the IR cirrus fluctuations, and are well
explained by randomly distributed point sources. Furthermore, point-to-point
comparison between 90 micron and 170 micron brightness shows a linear
correlation between them, and the slope of the linear fit is much shallower
than that expected from the IR cirrus color, and is consistent with the color
of galaxies at low or moderate redshift(z < 1). We conclude that the brightness
fluctuations in the Lockman Hole are not caused by the IR cirrus, but are most
likely due to faint star-forming galaxies. We also give the constraints on the
galaxy number counts down to 35 mJy at 90 micron and 60 mJy at 170 micron,
which indicate the existence of a strong evolution down to these fluxes in the
counts. The galaxies responsible for the fluctuations also significantly
contribute to the cosmic infrared background radiation.

</DOC>
<DOC>
<DOCNO> 122088 </DOCNO>
Lifting cosmic degeneracy within a single quasar survey


  In the almost Friedmann-Lema^itre model of the Universe, the density
parameter, Omega_matter, and the cosmological constant, Omega_Lambda, measure
curvature. Several linearly degenerate relations between these two parameters
have recently been measured. Here, large scale structure correlations at
\~100-150 h^-1 Mpc are found in the comoving three-dimensional separations of
redshift z \approx 2 quasars. These function as a comoving standard rod of
length L_LSS \approx 130+-10 h^-1 Mpc. A local maximum in the correlation
function at \approx L_LSS/2 also appears to be significant. By combining
separate radial and tangential standard ruler analyses, the lifting of the
Omega_matter - Omega_Lambda linear degeneracy within a single data set is
demonstrated for the first time.

</DOC>
<DOC>
<DOCNO> 170631 </DOCNO>
Optimal Creation of Entanglement Using a Two--Qubit Gate


  We consider a general unitary operator acting on two qubits in a product
state. We find the conditions such that the state of the qubits after the
action is as entangled as possible. We also consider the possibility of using
ancilla qubits to increase the entanglement.

</DOC>
<DOC>
<DOCNO> 13605 </DOCNO>
Auger spectroscopy of strongly correlated systems: present status and


  We review the Cini-Sawatzky approach to the line shape analysis of Auger CVV
transitions, in its basic and original formulation. Then, several extensions of
the theory are reviewed, namely the inclusion spin-orbit coupling,
dynamical/plasmon screening, overlap effects, off-site interactions, the
treatment of disorder and the formulation for partially filled bands. We
conclude by highlighting what we consider to be future directions in the field.

</DOC>
<DOC>
<DOCNO> 11176 </DOCNO>
Diblock Copolymer Ordering Induced by Patterned Surfaces Above the


  We investigate the morphology of diblock copolymers in the vicinity of flat,
chemically patterned surfaces. Using a Ginzburg-Landau free energy, spatial
variations of the order parameter are given in terms of a general
two-dimensional surface pattern above the order-disorder transition. The
propagation of several surface patterns into the bulk is investigated. The
oscillation period and decay length of the surface $q$-modes are calculated in
terms of system parameters. We observe lateral order parallel to the surface as
a result of order perpendicular to the surface. Surfaces which has a finite
size chemical pattern (e.g., a stripe of finite width) induces lamellar
ordering extending into the bulk. Close to the surface pattern the lamellae are
strongly perturbed adjusting to the pattern.

</DOC>
<DOC>
<DOCNO> 70076 </DOCNO>
Off-diagonal structure of neutrino mass matrix in see-saw mechanism and


  By a simple extension of the standard model in which ($e-\mu -\tau $)
universality is not conserved, we present a scenario within the framework of
see-saw mechanism in which the neutrino mass matrix is strictly off-diagonal in
the flavor basis. We show that a version of this scenario can accomodate the
atmospheric $\nu_\mu -\nu_\tau $ neutrino oscillations and $\nu_\mu -\nu_e$
oscillations claimed by the LSND collaboration.
  PACS: 14.60.Pq; 14.60.St;13.15.+g

</DOC>
<DOC>
<DOCNO> 169684 </DOCNO>
Multi-valued Logic Gates for Quantum Computation


  We develop a multi-valued logic for quantum computing for use in multi-level
quantum systems, and discuss the practical advantages of this approach for
scaling up a quantum computer. Generalizing the methods of binary quantum
logic, we establish that arbitrary unitary operations on any number of d-level
systems (d > 2) can be decomposed into logic gates that operate on only two
systems at a time. We show that such multi-valued logic gates are
experimentally feasible in the context of the linear ion trap scheme for
quantum computing. By using d levels in each ion in this scheme, we reduce the
number of ions needed for a computation by a factor of log d.

</DOC>
<DOC>
<DOCNO> 12432 </DOCNO>
A High-Resolution Compton Scattering Study of the Electron Momentum


  We report high-resolution Compton profiles (CP's) of Al along the three
principal symmetry directions at a photon energy of 59.38 keV, together with
corresponding highly accurate theoretical profiles obtained within the
local-density approximation (LDA) based band-theory framework. A good accord
between theory and experiment is found with respect to the overall shapes of
the CP's, their first and second derivatives, as well as the anisotropies in
the CP's defined as differences between pairs of various CP's. There are
however discrepancies in that, in comparison to the LDA predictions, the
measured profiles are lower at low momenta, show a Fermi cutoff which is
broader, and display a tail which is higher at momenta above the Fermi
momentum. A number of simple model calculations are carried out in order to
gain insight into the nature of the underlying 3D momentum density in Al, and
the role of the Fermi surface in inducing fine structure in the CP's. The
present results when compared with those on Li show clearly that the size of
discrepancies between theoretical and experimental CP's is markedly smaller in
Al than in Li. This indicates that, with increasing electron density, the
conventional picture of the electron gas becomes more representative of the
momentum density and that shortcomings of the LDA framework in describing the
electron correlation effects become less important.

</DOC>
<DOC>
<DOCNO> 102842 </DOCNO>
Automatic continuity and weighted composition operators between spaces


  It is proved that every linear biseparating map between spaces of
vector-valued differentiable functions is a weighted composition map. As a
consequence, such a map is always continuous.

</DOC>
<DOC>
<DOCNO> 84769 </DOCNO>
On the stress-energy tensor of a rotating wormhole


  We analyze the stress-energy tensor necessary to generate a general
stationary and axisymmetric spacetime. The constraints on the geometry arising
from considering a perfect fluid as a source are derived. For a fluid with a
nonzero stress tensor, we obtain two necessary conditions on the metric. As an
example, we show that the rotating wormhole presented in the literature can not
be described by either a perfect fluid or by a fluid with anisotropic stresses.

</DOC>
<DOC>
<DOCNO> 102358 </DOCNO>
Correlations between zeros and supersymmetry


  In our previous work [math-ph/9904020], we proved that the correlation
functions for simultaneous zeros of random generalized polynomials have
universal scaling limits and we gave explicit formulas for pair correlations in
codimensions 1 and 2. The purpose of this paper is to compute these universal
limits in all dimensions and codimensions. First, we use a supersymmetry method
to express the n-point correlations as Berezin integrals. Then we use the Wick
method to give a closed formula for the limit pair correlation function for the
point case in all dimensions.

</DOC>
<DOC>
<DOCNO> 85289 </DOCNO>
Effective one-body approach to the relativistic two-body problem


  The relativistic 2-body problem, much like the non-relativistic one, is
reduced to describing the motion of an effective particle in an external field.
The concept of a relativistic reduced mass and effective particle energy
introduced some 30 years ago to compute relativistic corrections to the Balmer
formula in quantum electrodynamics, is shown to work equally well for classical
electromagnetic and gravitational interaction. The results for the
gravitational 2-body problem have more than academic interest since they apply
to the study of binary pulsars that provide precision tests for general
relativity. They are compared with recent results derived by other methods.

</DOC>
<DOC>
<DOCNO> 69497 </DOCNO>
Model-independent analysis of the exclusive semileptonic B -> pi^+ pi^-


  A model-independent analysis for the exclusive, rare B -> pi^+ pi^- l^+ l^-
decay is presented. The dependence of the various physically measurable
asymmetries and CP violating asymmetry on the new Wilson coefficients is
studied in detail. It is observed that different measurable quantiles are very
sensitive to the different new Wilson coefficients, i.e., to the existence of
new physics beyond standard model.

</DOC>
<DOC>
<DOCNO> 8718 </DOCNO>
Self-organization, Localization of Shear Bands and Aging in Loose


  We introduce a mesoscopic model for the formation and evolution of shear
bands in loose granular media. Numerical simulations reveal that the system
undergoes a non-trivial self-organization process which is governed by the
motion of the shear band and the consequent restructuring of the material along
it. High density regions are built up, progressively confining the shear bands
in localized regions. This results in an inhomogeneous aging of the material
with a very slow increase in the mean density, displaying an unusual glassy
like system-size dependence.

</DOC>
<DOC>
<DOCNO> 169695 </DOCNO>
Nonlocal properties of two-qubit gates and mixed states and optimization


  Entanglement of two parts of a quantum system is a non-local property
unaffected by local manipulations of these parts. It is described by quantities
invariant under local unitary transformations. Here we present, for a system of
two qubits, a set of invariants which provides a complete description of
non-local properties. The set contains 18 real polynomials of the entries of
the density matrix. We prove that one of two mixed states can be transformed
into the other by single-bit operations if and only if these states have equal
values of all 18 invariants. Corresponding local operations can be found
efficiently. Without any of these 18 invariants the set is incomplete.
  Similarly, non-local, entangling properties of two-qubit unitary gates are
invariant under single-bit operations. We present a complete set of 3 real
polynomial invariants of unitary gates. Our results are useful for optimization
of quantum computations since they provide an effective tool to verify if and
how a given two-qubit operation can be performed using exactly one elementary
two-qubit gate, implemented by a basic physical manipulation (and arbitrarily
many single-bit gates).

</DOC>
<DOC>
<DOCNO> 12563 </DOCNO>
Bound states of infinite curved polymer chains


  We investigate an infinite array of point interactions of the same strength
in R^d, d=2,3, situated at vertices of a polygonal curve with a fixed edge
length. We demonstrate that if the curve is not a line, but it is
asymptotically straight in a suitable sense, the corresponding Hamiltonian has
bound states. Example is given in which the number of these bound states can
exceed any positive integer.

</DOC>
<DOC>
<DOCNO> 8514 </DOCNO>
Casimir Force between two Half Spaces of Vortex Matter in Anisotropic


  We present a new approach to calculate the attractive long-range
vortex-vortex interaction of the van der Waals type present in anisotropic and
layered superconductors. The mapping of the statistical mechanics of
two-dimensional charged bosons allows us to define a Casimir problem: Two half
spaces of vortex matter separated by a gap of width R are mapped to two
dielectric half planes of charged bosons interacting via a massive gauge field.
We determine the attractive Casimir force between the two half planes and show
that it agrees with the pairwise summation of the van der Waals force between
vortices.

</DOC>
<DOC>
<DOCNO> 12157 </DOCNO>
Local Atomic Strain in ZnSe(1-x)Te(x) from High Real Space Resolution


  High real-space resolution atomic pair distribution functions (PDFs) have
been obtained from ZnSe(1-x)Te(x) using neutron powder diffraction. Distinct
Zn-Se and Zn-Te nearest neighbor (nn) bonds, differing in length by delta_r=
0.14Angstroms, are resolved in the measured PDF allowing the evolution with
composition of the individual bond-lengths to be studied. The local
bond-lengths change much more slowly with doping than the average bond-length
obtained crystallographically. The nn bond-length distributions are constant
with doping but higher-neighbor pair distributions broaden significantly
indicating that most of the strain from the alloying is accommodated by
bond-bending forces in the alloy. The PDFs of alloys across the whole doping
range are well fit using a model based on the Kirkwood potential. The resulting
PDFs give excellent agreement with the measured PDFs over the entire alloy
range with no adjustable parameters.

</DOC>
<DOC>
<DOCNO> 121840 </DOCNO>
Evolution of Mass Distribution in CDM Halos


  On the basis of a new convergence study of high-resolution N-body
simulations, my colleagues and I now agree that the Navarro, Frenk, & White
(1996) density profile $\rho_{NFW}(r) \propto r^{-1} (r+r_s)^{-2}$ is a good
representation of typical dark matter halos of galactic mass. Comparing
simulations of the same halo with numbers of particles ranging from $\sim10^3$
to $\sim10^6$, we have also shown that $r_s$, the radius where the log-slope is
-2, can be determined accurately for halos with as few as $\sim10^3$ particles.
Based on a study of thousands of halos at many redshifts in an Adaptive
Refinement Tree (ART) simulation of a cosmological volume in a $\Lambda$CDM
cosmology, we have found that the concentration $\cvir \equiv \Rvir/\rs$ has a
log-normal distribution, with $1\sigma$ $\Delta (\log \cvir) = 0.18$ at a given
mass, corresponding to a scatter in maximum rotation velocities of $\Delta
\Vmax/\Vmax = 0.12$. The average concentration declines with redshift at fixed
mass as $\cvir(z) \propto (1+z)^{-1}$. This may have important implications for
galaxy rotation curves. Finally, we have found that the velocity function
determined from galaxy luminosity functions plus luminosity-velocity relations
agrees with the predictions from our $\Lambda$CDM simulations. But we also note
that the very limited evolution with redshift of the velocity function
predicted by $\Lambda$CDM conflicts with the data that is becoming available on
the number density of bright galaxies unless there is significant evolution of
the luminosity-velocity relation at $z>1$.

</DOC>
<DOC>
<DOCNO> 39827 </DOCNO>
Color reconnection and Bose-Einstein correlations at LEP2


  Recent investigations of final state interactions of W+W- events in e+e-
collisions up to center of mass energies sqrt{S}=189GeV at LEP2 are reviewed.
The data were used to look for color reconnection and Bose-Einstein
correlations between the two color singlets of fully hadronic W events.

</DOC>
<DOC>
<DOCNO> 70655 </DOCNO>
pi(-)p atom in ChPT: strong energy-level shift


  The general formula of the pi(-)p atom strong energy-level shift in the 1s
state is derived in the next-to-leading order in the isospin breaking, and in
all orders in chiral expansion. Isospin-breaking corrections to the level shift
are explicitly evaluated at order p^2 in ChPT. The results clearly demonstrate
the necessity to critically reaccess the values of the piN scattering lengths,
extracted from the energy-level shift measurement by means of the potential
model-based theoretical analysis.

</DOC>
<DOC>
<DOCNO> 11038 </DOCNO>
Disordered Type-II Superconductors: A Universal Phase Diagram for


  A universal phase diagram for weakly pinned low-T$_c$ type-II superconductors
is revisited and extended with new proposals. The low-temperature ``Bragg
glass'' phase is argued to transform first into a disordered, glassy phase upon
heating. This glassy phase, a continuation of the high-field equilibrium vortex
glass phase, then melts at higher temperatures into a liquid. This proposal
provides an explanation for the anomalies observed in the peak effect regime of
2H-NbSe$_2$ and several other low-T$_c$ materials which is independent of the
microscopic mechanisms of superconductivity in these systems.

</DOC>
<DOC>
<DOCNO> 9714 </DOCNO>
Fixed-boundary octagonal random tilings: a combinatorial approach


  Some combinatorial properties of fixed boundary rhombus random tilings with
octagonal symmetry are studied. A geometrical analysis of their configuration
space is given as well as a description in terms of discrete dynamical systems,
thus generalizing previous results on the more restricted class of
codimension-one tilings. In particular this method gives access to counting
formulas, which are directly related to questions of entropy in these
statistical systems. Methods and tools from the field of enumerative
combinatorics are used.

</DOC>
<DOC>
<DOCNO> 116674 </DOCNO>
Upgrade of the PEP-II Low Beta Optics


  The successful commissioning and operation of the PEP-II asymmetric e+e-
collider motivated further studies to increase luminosity. In this paper, we
discuss a modification of the PEP-II lattice to reduce the vertical beta
function at the Interaction Point (IP) from the design value of 1.5cm to 1.0cm.
This could potentially reduce the colliding beam size, increase particle
density at the IP and the probability of beam-beam interactions. In this paper,
we outline the optics modifications, discuss tracking simulations, and overview
machine implementation.

</DOC>
<DOC>
<DOCNO> 170340 </DOCNO>
Exact relativistic time evolution for a step potential barrier


  We derive an exact analytic solution to a Klein-Gordon equation for a step
potential barrier with cutoff plane wave initial conditions, in order to
explore wave evolution in a classical forbidden region. We find that the
relativistic solution rapidly evanesces within a depth $2x_p$ inside the
potential, where $x_p$ is the penetration length of the stationary solution.
Beyond the characteristic distance $2x_p$, a Sommerfeld-type precursor travels
along the potential at the speed of light, $c$. However, no spatial propagation
of a main wavefront along the structure is observed. We also find a non-causal
time evolution of the wavefront peak. The effect is only an apparent violation
of Einstein causality.

</DOC>
<DOC>
<DOCNO> 71675 </DOCNO>
Inflationary Brans-Dicke Quantum Universe II: Particular evolutions and


  We made an analysis of the equations of motion which are obtained from the
one - loop effective action for Brans-Dicke gravity with N dilaton - coupled
massless fermions in a time-dependent conformally flat background. Various
particular solutions, including the well-known stationary one, of the
corresponding set of first-order differential equations are given. Some of
these solutions describe an expanding time-dependent Universe with increasing,
constant or also decreasing dilaton. This is illustrated by a numerical
analysis. For the nonstationary solutions a stability analysis is given.

</DOC>
<DOC>
<DOCNO> 150407 </DOCNO>
D-Sphalerons and the Topology of String Configuration Space


  We show that unstable D-branes play the role of ``D-sphalerons'' in string
theory. Their existence implies that the configuration space of Type II string
theory has a complicated homotopy structure, similar to that of an infinite
Grassmannian. In particular, the configuration space of Type IIA (IIB) string
theory on $\R^{10}$ has non-trivial homotopy groups $\pi_k$ for all $k$ even
(odd).

</DOC>
<DOC>
<DOCNO> 152025 </DOCNO>
Lorentz harmonics and superfield action. D=10, N=1 superstring


  We propose a new version of the superfield action for a closed D=10, N=1
superstring where the Lorentz harmonics are used as auxiliary superfields. The
incorporation of Lorentz harmonics into the superfield action makes possible to
obtain superfield constraints of the induced worldsheet supergravity as
equations of motion. Moreover, it becomes evident that a so-called 'Wess-Zumino
part' of the superfield action is basically a Lagrangian form of the
generalized action principle. We propose to use the second Noether theorem to
handle the essential terms in the transformation lows of hidden gauge
symmetries, which remove dynamical degrees of freedom from the Lagrange
multiplier superfield.

</DOC>
<DOC>
<DOCNO> 118668 </DOCNO>
Goodness-of-Fit Analysis of Radial Velocities Surveys


  Using eigenmode expansion of the Mark-3 and SFI surveys of cosmological
radial velocities a goodness-of-fit analysis is applied on a mode-by-mode
basis. This differential analysis complements theBayesian maximum likelihood
analysis that finds the most probable model given the data. Analyzing the
surveys with their corresponding most likely models from the CMB-like family of
models, as well as with the currently popular Lambda-CDM model, reveals a
systematic inconsistency of the data with these `best' models. There is a
systematic trend of the cumulative chi^2 to increase with the mode number
(where the modes are sorted by decreasing order of the eigenvalues). This
corresponds to a decrease of the chi^2 with the variance associated with a
mode, and hence with its effective scale. It follows that the differential
analysis finds that on small (large) scales the global analysis of all the
modes `puts' less (more) power than actually required by the data. This
observed trend might indicate one of the followings: a. The theoretical model
(i.e. power spectrum) or the error model (or both) have an excess of power on
large scales; b. Velocity bias; c. The velocity data suffers from still
uncorrected systematic errors.

</DOC>
<DOC>
<DOCNO> 70634 </DOCNO>
Bounds on masses of new gauge bosons in the 3 - 3 -1 models


  Contribution from new gauge bosons in the 3 - 3 - 1 models to the anomalous
magnetic moment of the muon, mass difference of the kaon system and rare kaon
decay are calculated and numerically estimated. Bounds on masses of new gauge
bosons: bileptons and Z' are derived.

</DOC>
<DOC>
<DOCNO> 151828 </DOCNO>
On the sqrt{2} puzzle in AdS_2/CFT_1


  In this letter we analyze the Hamiltonian formulation of the
Jackiw-Teitelboim model of 2D gravity and calculate the central charge
associated with the asymptotic symmetries, taking care of boundary terms. For
black hole solutions, we show that there is no sqrt{2} discrepancy between the
thermodynamical entropy and the statistical one obtained via Cardy's formula.

</DOC>
<DOC>
<DOCNO> 151536 </DOCNO>
Ricci-Parallelizable Spaces in the NS-NS Sector: AdS_3 x S^7


  We provide a class of nondilatonic solutions to the NS-NS sector of string
theory. The solutions consist of products of Ricci-parallelizable spaces with
adjusted radii. A representative of this class, AdS_3 x S^7, is presented in
detail. Some comments on possible brane connections are made.

</DOC>
<DOC>
<DOCNO> 118326 </DOCNO>
Not enough stellar Mass Machos in the Galactic Halo


  We combine new results from the search for microlensing towards the Large
Magellanic Cloud (LMC) by EROS2 (Experience de Recherche d'Objets Sombres) with
limits previously reported by EROS1 and EROS2 towards both Magellanic Clouds.
The derived upper limit on the abundance of stellar mass MACHOs rules out such
objects as an important component of the Galactic halo if their mass is smaller
than 1 solar mass.

</DOC>
<DOC>
<DOCNO> 85542 </DOCNO>
The Fundamental Commutator For Massless Particles


  It is discussed that the usual Heisenberg commutation relation (CR) is not a
proper relation for massless particles and then an alternative is obtained. The
canonical quantization of the free electromagnetic(EM)fields based on the field
theoretical generalization of this alternative is carried out. Without imposing
the normal ordering condition,the vacuum energy is automatically zero.This can
be considered as a solution to the EM fields vacuum catastrophe and a step
toward managing the cosmologial constant problem at least for the EM fields
contribution to the state of vacuum.

</DOC>
<DOC>
<DOCNO> 80622 </DOCNO>
Domain-Wall Induced Quark Masses in Topologically-Nontrivial Background


  In the domain-wall formulation of chiral fermion, the finite separation
between domain-walls ($L_s$) induces an effective quark mass ($m_{\rm eff}$)
which complicates the chiral limit. In this work, we study the size of the
effective mass as the function of $L_s$ and the domain-wall height $m_0$ by
calculating the smallest eigenvalue of the hermitian domain-wall Dirac operator
in the topologically-nontrivial background fields. We find that, just like in
the free case, $m_{\rm eff}$ decreases exponentially in $L_s$ with a rate
depending on $m_0$. However, quantum fluctuations amplify the wall effects
significantly. Our numerical result is consistent with a previous study of the
effective mass from the Gell-Mann-Oakes-Renner relation.

</DOC>
<DOC>
<DOCNO> 123183 </DOCNO>
BeppoSAX study of the broad-band properties of luminous globular cluster


  We have performed a detailed study of the broadband spectra of the luminous
globular cluster X-ray sources using BeppoSAX. With the exception of X2127+119,
located in NGC7078, all the other spectra are well represented by a two
component model consisting of a disk-blackbody and Comptonized emission. The
measured low-energy absorptions are in good agreement with those predicted from
optical measurements of the host globular clusters. This implies that there is
little intrinsic X-ray absorption within the binaries themselves, and that the
above spectral model provides a good representation of the low-energy continua.
The sources can be divided into two groups. In the first group, composed of 3
ultra-compact (orbital period <1hr) sources, the disk-blackbody temperatures
and inner-radii appear physically realistic and the Comptonization seed photons
temperatures and radii of the emission areas are consistent with the disk
temperatures and inner radii. For all the other sources, the disk-blackbody
parameters appear not to be physically realistic and the Comptonization
parameters are unrelated to those of the disk-blackbody emission. If this is a
spectral signature of ultra-compact binaries, this implies that no other
ultra-compact binaries are present among those studied here. It is unclear why
this difference between the two types of binaries should exist.

</DOC>
<DOC>
<DOCNO> 8126 </DOCNO>
Modes of counterion density-fluctuations and counterion-mediated


  Counterion-mediated attractions between like-charged fluid membranes are
long-ranged and non-pairwise additive at high temperatures. At zero
temperature, however, they are pairwise additive and decay exponentially with
the membrane separation. Here we show that the nature of these attractions is
determined by the dominant modes of fluctuations in the density of counterions.
While the non-pairwise additive interactions arise from long-wavelength
fluctuations and vanish at zero temperature, the short-ranged pairwise additive
interactions arise from short-wavelength fluctuations and are stronger at low
temperatures.

</DOC>
<DOC>
<DOCNO> 117792 </DOCNO>
Infrared Properties of High Redshift and X-ray Selected AGN Samples


  The NASA/ISO Key Project on active galactic nuclei (AGN) seeks to better
understand the broad-band spectral energy distributions (SEDs) of these sources
from radio to X-rays, with particular emphasis on infrared properties. The ISO
sample includes a wide variety of AGN types and spans a large redshift range.
Two subsamples are considered herein: 8 high-redshift (1 < z < 4.7) quasars;
and 22 hard X-ray selected sources.
  The X-ray selected AGN show a wide range of IR continuum shapes, extending to
cooler colors than the optical/radio sample of Elvis et al. (1994). Where a
far-IR turnover is clearly observed, the slopes are < 2.5 in all but one case
so that non-thermal emission remains a possibility. The highest redshift
quasars show extremely strong, hot IR continua requiring ~ 100 solar masses of
500 - 1000 Kelvin dust with ~ 100 times weaker optical emission. Possible
explanations for these unusual properties include: reflection of the optical
light from material above/below a torus; strong obscuration of the optical
continuum; or an intrinsic deficit of optical emission.

</DOC>
<DOC>
<DOCNO> 151530 </DOCNO>
Brane Configurations of BPS Domain Walls for the N=1^* SU(N) Gauge


  We study supersymmetric domain walls in N=1 SU(N) gauge theory with 3 massive
adjoint representation chiral multiplets. This theory, known as N=1^*, can be
obtained as a massive deformation of N=4 Yang-Mills theory. Following
Polchinski and Strassler, we consider the string dual of this theory in terms
of spherical 5-branes and construct BPS domain walls interpolating between the
many vacua. We compare our results to field theoretic domain walls and also
find that this work is related to the physics of expanded ``dielectric'' branes
near zero radius.

</DOC>
<DOC>
<DOCNO> 11993 </DOCNO>
Quantum-Classical Correspondence for Isolated Systems of Interacting


  Generic properties of the strength function (local density of states (LDOS))
and chaotic eigenstates are analyzed for isolated systems of interacting
particles. Both random matrix models and dynamical systems are considered in
the unique approach. Specific attention is paid to the quantum-classical
correspondence for the form of the LDOS and eigenstates, and to the
localization in the energy shell. New effect of the non-ergodicity of
individual eigenstates in a deep semiclassical limit is briefly discussed.

</DOC>
<DOC>
<DOCNO> 151502 </DOCNO>
D=4, N=1 orientifolds with vector structure


  We construct compact type IIB orientifolds with discrete groups Z_4, Z_6,
Z_6', Z_8, Z_12 and Z_12'. These models are N=1 supersymmetric in D=4 and have
vector structure. The possibility of having vector structure in Z_N
orientifolds with even N arises due to an alternative Omega-projection in the
twisted sectors. Some of the models without vector structure are known to be
inconsistent because of uncancelled tadpoles. We show that vector structure
leads to a sign flip in the twisted Klein bottle contribution. As a
consequence, all the tadpoles can be cancelled by introducing D9-branes and
D5-branes.

</DOC>
<DOC>
<DOCNO> 39714 </DOCNO>
Atomic Parity Violation, Leptoquarks, and Contact Interactions


  The recent measurement of atomic parity violation in cesium atoms shows a
$2.3\sigma$ deviation from the standard model prediction. We show that such an
effect can be explained by four-fermion contact interactions with specific
chiralities or by scalar leptoquarks which couple to the left-handed quarks.
For a coupling of electromagnetic strength, the leptoquark mass is inferred to
be 1.1 to 1.3 TeV. We also show that these solutions are consistent with all
other low-energy and high-energy neutral-current data.

</DOC>
<DOC>
<DOCNO> 120833 </DOCNO>
An accelerated Monte Carlo method to solve two-dimensional radiative


  We present a numerical method and computer code to calculate the radiative
transfer and excitation of molecular lines. Formulating the Monte Carlo method
from the viewpoint of cells rather than photons allows us to separate local and
external contributions to the radiation field. This separation is critical to
accurate and fast performance at high optical depths (tau>100). The random
nature of the Monte Carlo method serves to verify the independence of the
solution to the angular, spatial, and frequency sampling of the radiation
field. These features allow use of our method in a wide variety of
astrophysical problems without specific adaptations: in any axially symmetric
source model and for all atoms or molecules for which collisional rate
coefficients are available. Continuum emission and absorption by dust is
explicitly taken into account but scattering is neglected. We illustrate these
features in calculations of (i) the HCO+ J=1-0 and 3-2 emission from a
flattened protostellar envelope with infall and rotation, (ii) the CO, HCO+, CN
and HCN emission from a protoplanetary disk and (iii) HCN emission from a
high-mass young stellar object, where infrared pumping is important. The
program can be used for optical depths up to 1000-10,000, depending on source
model. We expect this program to be an important tool in analysing data from
present and future infrared and (sub) millimetre telescopes.

</DOC>
<DOC>
<DOCNO> 151113 </DOCNO>
Schwinger Pair Production via Instantons in Strong Electric Fields


  In the space-dependent gauge, each mode of the Klein-Gordon equation in a
strong electric field takes the form of a time-independent Schr\"{o}dinger
equation with a potential barrier. We propose that the single- and
multi-instantons of quantum tunneling may be related with the single- and
multi-pair production of bosons and the relative probability for the no-pair
production is determined by the total tunneling probability via instantons. In
the case of a uniform electric field, the instanton interpretation recovers
exactly the well-known pair production rate for bosons and when the Pauli
blocking is taken into account, it gives the correct fermion production rate.
The instanton is used to calculate the pair production rate even in an
inhomogeneous electric field. Furthermore, the instanton interpretation
confirms the fact that bosons and fermions can not be produced by a static
magnetic field only.

</DOC>
<DOC>
<DOCNO> 150664 </DOCNO>
Black Holes and U-duality in Diverse Dimensions


  In this paper we review some properties of BPS black holes of supergravities
with n=32,16 supersymmetries. The BPS condition, a condition on the eigenvalues
of the central charge matrix, can be shown to be U-duality invariant. We
explicitly work out D=4, N=8 and D=5, N=4 supergravities.

</DOC>
<DOC>
<DOCNO> 116858 </DOCNO>
CLIC, a Two-Beam Multi-TeV e+e- Linear Collider


  The CLIC study of a high-energy (0.5 - 5 TeV), high-luminosity (1034 - 1035
cm-2 sec-1) e+e- linear collider is presented. Beam acceleration using high
frequency (30 GHz) normal-conducting structures operating at high accelerating
fields (150 MV/m) significantly reduces the length and, in consequence, the
cost of the linac. Using parameters derived from general scaling laws for
linear colliders, the beam stability is shown to be similar to lower frequency
designs in spite of the strong wake-field dependency on frequency. A new
cost-effective and efficient drive beam generation scheme for RF power
production by the so-called "Two-Beam Acceleration" method is described. It
uses a thermionic gun and a fully-loaded normal-conducting linac operating at
low frequency (937 MHz) to generate and accelerate the drive beam bunches, and
RF multiplication by funnelling in compressor rings to produce the desired
bunch structure. Recent 30 GHz hardware developments and CLIC Test Facility
(CTF) results are described.

</DOC>
<DOC>
<DOCNO> 11289 </DOCNO>
Dephasing of Electrons on Helium by Collisions with Gas Atoms


  The damping of quantum effects in the transport properties of electrons
deposited on a surface of liquid helium is studied. It is found that due to
vertical motion of the helium vapour atoms the interference of paths of
duration $t$ is damped by a factor $\exp - (t/\tau_v)^3$. An expression is
derived for the weak-localization lineshape in the case that damping occurs by
a combination of processes with this type of cubic exponential damping and
processes with a simple exponential damping factor.

</DOC>
<DOC>
<DOCNO> 101911 </DOCNO>
Quadratic algebras :Three-mode bosonic realizations and applications


  Quadratic algebras of the type $\lsb Q_0, Q_\pm \rsb$ $=$ $\pm Q_\pm$, $\lsb
Q_+, Q_- \rsb$ $=$ $aQ_0^2 + bQ_0 + c$ are studied using three-mode bosonic
realizations. Matrix representations and single variable differential operator
realizations are obtained. Examples of physical relevance of such algebras are
given.

</DOC>
<DOC>
<DOCNO> 67921 </DOCNO>
Large Mixing Angle MSW Solution in S_3 Flavor Symmetry


  We have investigated phenomenological implications on the neutrino flavor
mixings in the $S_{3L}\times S_{3R}$ symmetric mass matrices including symmetry
breaking terms. We have shown how to get the large mixing angle MSW solution,
$\sin^2 2 \th_\odot=0.65\sim 0.97$ and $\Delta m_{\odot}^2= 10^{-5}\sim
10^{-4}\eV^2$, in this model. It is found that the structure of the lepton mass
matrix in our model is stable against radiative corrections although the model
leads to nearly degenerate neutrinos.

</DOC>
<DOC>
<DOCNO> 118434 </DOCNO>
The massive stellar content in NGC604 and its evolutionary state


  The ultraviolet resonance wind stellar lines, the nebular optical emission
lines and the higher order terms of the Balmer series and HeI absorption lines
detected in the spectra of NGC 604 are interpreted using evolutionary models
optimized for young star forming regions. The evolutionary state and the
massive stellar content of the region is derived in a self-consistent way.
  The three techniques applied suggest that the central ionizing cluster in NGC
604 is very young, 3 Myr old, and that the stars in the cluster were formed in
an instantaneous burst following a Salpeter or flatter IMF, having stars more
massive that 80 Msol. The stellar cluster is able to provide most of the
ionizing photons needed to photoionize the whole nebula, and the wind power to
form the central shell structure where the cluster core is located. The stellar
cluster is affected by an extinction similar to the average extinction that
affects the ionized gas. The estimated number of massive stars in the cluster
is also in agreement with that derived from previous studies based on the
detection of individual stars. The results that we present here support the use
of these techniques for the interpretation of the integrated light of more
distant star forming regions

</DOC>
<DOC>
<DOCNO> 70440 </DOCNO>
Chiral Ward identities and pion propagation at finite temperature in the


  Working within the linear sigma model at finite temperature, we construct
effective one-loop vertices and propagators satisfying the chiral Ward
identities, for small pion momentum and mass compared to the sigma mass. We
obtain an expansion for the pion dispersion relation up to second order in the
parameter m_pi^2/4pi^2f_pi^2. At leading order, this expansion reproduces the
dispersion curve obtained in chiral perturbation theory. We also study pion
damping and compute the mean free path for pions traveling in the medium before
forming a sigma resonance. These results are also in good agreement with chiral
perturbation theory when using a value for the sigma mass of 600 MeV.

</DOC>
<DOC>
<DOCNO> 9698 </DOCNO>
Ground State Entropy of the Potts Antiferromagnet on Triangular Lattice


  We present exact calculations of the zero-temperature partition function
(chromatic polynomial) $P$ for the $q$-state Potts antiferromagnet on
triangular lattice strips of arbitrarily great length $L_x$ vertices and of
width $L_y=3$ vertices and, in the $L_x \to \infty$ limit, the exponent of the
ground-state entropy, $W=e^{S_0/k_B}$. The strips considered, with their
boundary conditions ($BC$) are (a) $(FBC_y,PBC_x)=$ cyclic, (b)
$(FBC_y,TPBC_x)=$ M\"obius, (c) $(PBC_y,PBC_x)=$ toroidal, and (d)
$(PBC_y,TPBC_x)=$ Klein bottle, where $F$, $P$, and $TP$ denote free, periodic,
and twisted periodic. Exact calculations of $P$ and $W$ are also given for
wider strips, including (e) cyclic, $L_y=4$, and (f) $(PBC_y,FBC_x)=$
cylindrical, $L_y=5,6$. Several interesting features are found, including the
presence of terms in $P$ proportional to $\cos(2\pi L_x/3)$ for case (c). The
continuous locus of points ${\cal B}$ where $W$ is nonanalytic in the $q$ plane
is discussed for each case and a comparative discussion is given of the
respective loci ${\cal B}$ for families with different boundary conditions.
Numerical values of $W$ are given for infinite-length strips of various widths
and are shown to approach values for the 2D lattice rapidly. A remark is also
made concerning a zero-free region for chromatic zeros.

</DOC>
<DOC>
<DOCNO> 102818 </DOCNO>
The Ito Formula for Essentially Self-Adjoint Quantum Semimartingales


  The quantum Ito formula has so far been proved for regular (bounded) quantum
semimartingales We give three different extensions to classes of essentially
self-adjoint (unbounded) quantum semimartingales.
  The first extension is to quantum semimartingales whose integrands have chaos
matrices controlled by certain scalar matrices
  The second extension is to perturbations of classical, possibly unbounded,
quantum semimartingales by bounded quantum semimartingales
  The third extension is obtained by perturbing an essentially self-adjoint
quantum semimartingale satisfying the quantum Duhamel formula by a regular
quantum semimartingle.

</DOC>
<DOC>
<DOCNO> 7725 </DOCNO>
Dynamical aspects of a three-dimensional Heisenberg spin glass


  Spin-glass and chiral-glass orderings of a three-dimensional isotropic
Heisenberg spin glass are studied both by equilibrium and off-equilibrium Monte
Carlo simulations with emphasis on their dynamical aspects. The model is found
to exhibit a finite-temperature chiral-glass transition without the
conventional spin-glass order. Although chirality is an Ising-like quantity
from symmetry, universality class of the chiral-glass transition appears to be
different from that of the standard Ising spin glass. In the off-equilibrium
simulation, while the spin autocorrelation exhibits only an interrupted aging,
the chirality autocorrelation persists to exhibit a pronounced aging effect
reminiscent of the one observered in the mean-field model.

</DOC>
<DOC>
<DOCNO> 40171 </DOCNO>
Search for a Higgs Boson Decaying into Two Photons in e+e- Interactions


  A search is performed for a Higgs boson produced in association with a Z
boson and decaying into two photons, using the L3 data collected at LEP at a
centre-of-mass energy of 189 GeV. All decay modes of the Z are considered. No
signal is observed and limits on the branching fraction of the Higgs boson
decay into two photons as a function of the Higgs mass are derived assuming a
Standard Model production rate. A lower limit on the mass of a fermiophobic
Higgs is set at 94.9 GeV at 95% confidence level.

</DOC>
<DOC>
<DOCNO> 122763 </DOCNO>
Galaxy Formation at z~3: Constraints from Spatial Clustering


  We use N-body simulations combined with semi-analytic models to compute the
clustering properties of modeled galaxies at z~3, and confront these
predictions with the clustering properties of the observed population of
Lyman-break galaxies (LBGs). Several scenarios for the nature of LBGs are
explored, which may be broadly categorized into models in which high-redshift
star formation is driven by collisional starbursts and those in which quiescent
star formation dominates. For each model, we make predictions for the LBG
overdensity distribution, the variance of counts-in-cells, the correlation
length, and close pair statistics. Models which assume a one-to-one
relationship between massive dark-matter halos and galaxies are disfavored by
close pair statistics, as are models in which colliding halos are associated
with galaxies in a simplified way. However, when modeling of gas consumption
and star formation is included using a semi-analytic treatment, the quiescent
and collisional starburst models predict similar clustering properties and none
of these models can be ruled out based on the available clustering data. None
of the ``realistic'' models predict a strong dependence of clustering amplitude
on the luminosity threshold of the sample, in apparent conflict with some
observational results.

</DOC>
<DOC>
<DOCNO> 68958 </DOCNO>
Neutrino Oscillations and the Solar Neutrino Problem


  I describe the current status of the solar neutrino problem, summarizing the
arguments that its resolution will require new particle physics. The phenomenon
of matter-enhanced neutrino oscillations is reviewed. I consider the
implications of current experiments -- including the SuperKamiokande
atmospheric and LSND measurements -- and the need for additional constraints
from SNO and other new detectors.

</DOC>
<DOC>
<DOCNO> 99736 </DOCNO>
Towards a combinatorial Intersection Cohomology for Fans


  The real intersection cohomology of a toric variety is described in a purely
combinatorial way using methods of elementary commutative algebra only. We
define, for arbitrary fans, the notion of a ``minimal extension sheaf'' on the
fan as an axiomatic characterization of the equivariant intersection cohomology
sheaf. This provides a purely algebraic interpretation of Stanley's generalized
f- and g-vector of an arbitrary polytope or complete fan under a natural
vanishing condition. -- The results presented in this note originate from joint
work with G.Barthel, J.-P.Brasselet and L.Kaup, continuing earlier research
(see math.AG/9904159). A detailed exposition will appear elsewhere (see
math.AG/0002181).

</DOC>
<DOC>
<DOCNO> 8348 </DOCNO>
The travelling salesman problem on randomly diluted lattices: results


  If one places N cities randomly on a lattice of size L, we find that the
normalized optimal travel distances per city in the Euclidean and Manhattan
metrics vary monotonically with the city concentration p. We have studied such
optimal tours for visiting all the cities using a branch and bound algorithm,
giving exact optimized tours for small system sizes (N<100). Extrapolating the
results for N tending to infinity, we find that the normalized optimal travel
distances per city in the Euclidean and Manhattan metrics both equal unity for
p=1, and they reduce to about 0.74 and 0.94, respectively, as p tends to zero.
Although the problem is trivial for p=1, it certainly reduces to the standard
TSP on continuum (NP-hard problem) for p tending to zero. We did not observe
any irregular behaviour at any intermediate point. The crossover from the
triviality to the NP-hard problem seems to occur at p=1.

</DOC>
<DOC>
<DOCNO> 68899 </DOCNO>
Leading twist asymmetries in deeply virtual Compton scattering


  We calculate spin, charge, and azimuthal asymmetries in deeply virtual
Compton scattering at leading twist-two level. The measurement of these
asymmetries gives an access to the imaginary and real part of all deeply
virtual Compton scattering amplitudes. We note that a consistent description of
this process requires taking into account twist-three contributions and give
then a model dependent estimate of these asymmetries.

</DOC>
<DOC>
<DOCNO> 72158 </DOCNO>
Implications of CP and CPT for production and decay of Majorana fermions


  The consequences of CP- and CPT-invariance for production and subsequent
decay of Majorana fermions are analytically studied. We derive general symmetry
relations for the spin density matrix for production of Majorana fermions by
polarized fermion-antifermion annihilation which allow to distinguish Majorana
from Dirac fermions. We discuss the influence of the spin correlations on
energy and angular distributions of the decay products. Numerical results are
shown for the production of neutralinos and charginos with subsequent leptonic
decay at a future linear collider with longitudinally polarized beams.

</DOC>
<DOC>
<DOCNO> 170362 </DOCNO>
Implementing universal multi-qubit quantum logic gates in three and


  In this paper, we present the experimental realization of multi-qubit gates
$% \Lambda_n(not) $ in macroscopic ensemble of three-qubit and four-qubit
molecules. Instead of depending heavily on the two-bit universal gate, which
served as the basic quantum operation in quantum computing, we use pulses of
well-defined frequency and length that simultaneously apply to all qubits in a
quantum register. It appears that this method is experimentally convenient when
this procedure is extended to more qubits on some quantum computation, and it
can also be used in other physical systems.

</DOC>
<DOC>
<DOCNO> 121109 </DOCNO>
Spherically symmetric model atmospheres for low mass pre-Main Sequence


  We present a grid of spherically symmetric model atmospheres for young pre-MS
stars. This grid spans the parameter range $2000\K \leq \Teff \leq 6800\K$ and
$2.0 \leq \logg \leq 3.5$ for $M=0.1\Msun$, appropriate for low mass stars and
brown dwarfs. A major improvement is the replacement of TiO and \water line
lists with the newer line list calculated by the NASA-AMES group, for TiO
(about 175 million lines of 5 isotopes) and for \water (about 350 million lines
in 2 isotopes). We provide the model structures, spectra and broad-band colors
in standard filters in electronic form.

</DOC>
<DOC>
<DOCNO> 8061 </DOCNO>
A numerical study of the formation of magnetisation plateaus in quasi


  We study the magnetisation process of the one dimensional spin-1/2
antiferromagnetic Heisenberg model with modulated couplings over j=1,2,3
sites. It turns out that the evolution of magnetisation plateaus depends on j
and on the wave number q of the modulation according to the rule of Oshikawa,
et al. A mapping of two- and three-leg zig-zag ladders on one
dimensional systems with modulated couplings yields predictions for the
occurence of magnetization plateaus. The latter are tested by numerical
computations with the DMRG algorithm.

</DOC>
<DOC>
<DOCNO> 101102 </DOCNO>
Invariant Means


  Let m(a,b) and M(a,b,c) be symmetric means. We say that M is type 1 invariant
with respect to m if M(m(a,c),m(a,b),m(b,c)) = M(a,b,c) for all a, b, c > 0. If
m is strict and isotone, then we show that there exists a unique M which is
type 1 invariant with respect to m. In particular we discuss the invariant
logarithmic mean L_3, which is type 1 invariant with respect to L(a,b) =
(b-a)/(log b-log a). We say that M is type 2 invariant with respect to m if
M(a,b,m(a,b)) = m(a,b) for all a, b > 0. We also prove existence and uniqueness
results for type 2 invariance, given the mean M(a,b,c). The arithmetic,
geometric, and harmonic means in two and three variables satisfy both type 1
and type 2 invariance. There are means m and M such that M is type 2 invariant
with respect to m, but not type 1 invariant with respect to m(for example, the
Lehmer means). L_3 is type 1 invariant with respect to L, but not type 2
invariant with respect to L.

</DOC>
<DOC>
<DOCNO> 7861 </DOCNO>
A String Approximation for Cooper Pair in High-T$_{\bf c}$


  It is assumed that in some sense the High-T$_c$ superconductivity is similar
to the quantum chromodynamics (QCD). This means that the phonons in High-T$_c$
superconductor have the strong interaction between themselves like to gluons in
the QCD. At the experimental level this means that in High-T$_c$ superconductor
exists the nonlinear sound waves. It is possible that the existence of the
strong phonon-phonon interaction leads to the confinement of phonons into a
phonon tube (PT) stretched between two Cooper electrons like a hypothesized
flux tube between quark and antiquark in the QCD. The flux tube in the QCD
brings to a very strong interaction between quark-antiquark, the similar
situation can be in the High-T$_c$ superconductor: the presence of the PT can
essentially increase the binding energy for the Cooper pair. In the first rough
approximation the PT can be approximated as a nonrelativistic string with
Cooper electrons at the ends. The BCS theory with such potential term is
considered. It is shown that Green's function method in the superconductivity
theory is a realization of discussed Heisenberg idea proposed by him for the
quantization of nonlinear spinor field. A possible experimental testing for the
string approximation of the Cooper pair is offered.

</DOC>
<DOC>
<DOCNO> 11672 </DOCNO>
Effective attraction between like-charged colloids in a 2D plasma


  The existence of attractions between like-charged colloids immersed in ionic
solution have been discovered in recent experiments. This phenomenon
contradicts the predictions of DLVO theory and indicates a failure of mean
field theory. We study a toy model based on a two dimensional one-component
plasma, which is exactly soluble at one particular coupling constant. We show
that colloidal interaction results from a competition between ion-ion repulsion
and longer ranged ion-void attraction.

</DOC>
<DOC>
<DOCNO> 9240 </DOCNO>
Partition function zeros and leading order scaling correction of the 3D


  The density of states for the three-dimensional Ising model is calculated
with high-precision from multicanonical simulations. This allows us to estimate
the leading partition function zeros for lattice sizes up to L=32. Combining
previous statistics for smaller lattice sizes, we have evaluated the correction
to scaling and the critical exponent $\nu$ through out an analysis of a
multi-parameter fit and of Bulirsch-Stoer (BST) extrapolation algorithm. The
performance of the BST algorithm is also explored in case of the 2D Ising
model, where the exact partition function zeros are known.

</DOC>
<DOC>
<DOCNO> 122224 </DOCNO>
Complex resonance absorption structure in the X-ray spectrum of


  The luminous infrared-loud quasar IRAS 13349+2438 was observed with the
XMM-Newton Observatory as part of the Performance Verification program. The
spectrum obtained by the Reflection Grating Spectrometer (RGS) exhibits broad
(v ~ 1400 km/s FWHM) absorption lines from highly ionized elements including
hydrogen- and helium-like carbon, nitrogen, oxygen, and neon, and several iron
L-shell ions (Fe XVII - XX). Also shown in the spectrum is the first
astrophysical detection of a broad absorption feature around lambda = 16 - 17
Ang identified as an unresolved transition array (UTA) of 2p - 3d inner-shell
absorption by iron M-shell ions in a much cooler medium; a feature that might
be misidentified as an O VII edge when observed with moderate resolution
spectrometers. No absorption edges are clearly detected in the spectrum. We
demonstrate that the RGS spectrum of IRAS 13349+2438 exhibits absorption lines
from at least two distinct regions, one of which is tentatively associated with
the medium that produces the optical/UV reddening.

</DOC>
<DOC>
<DOCNO> 39826 </DOCNO>
Elastic Photoproduction of J/psi and Upsilon Mesons at HERA


  Cross sections for elastic photoproduction of J/Psi and Upsilon mesons are
presented. For J/Psi mesons the dependence on the photon-proton centre-of-mass
energy W_gammap is analysed in an extended range with respect to previous
measurements of 26<=W_gammap<= 285 GeV. The measured energy dependence is
parameterized as sigma_gammap proportional W_gammap^delta with
delta=0.83+-0.07. The differential cross section dsigma/dt for J/Psi mesons is
derived, its dependence on W_gammap and on t is analysed and the effective
trajectory (in terms of Regge theory) is determined to be
alpha(t)=(1.27+-0.05)+(0.08+-0.17)*t/GeV^2. Models based on perturbative QCD
and on pomeron exchange are compared to the data.

</DOC>
<DOC>
<DOCNO> 119535 </DOCNO>
The evolution of the galactic morphological types in clusters


  The morphological types of galaxies in nine clusters in the redshift range
0.1<z<0.25 are derived from very good seeing images taken at the NOT and the La
Silla Danish telescopes. With the purpose of investigating the evolution of the
fraction of different morphological types with redshift, we compare our results
with the morphological content of nine distant clusters studied by the MORPHS
group, five clusters observed with HST-WFPC2 at redshift z = 0.2-0.3, and
Dressler's (1980) large sample of nearby clusters. After having checked the
reliability of our morphological classification both in an absolute sense and
relative to the MORPHS scheme, we analyze the relative occurrence of
elliptical, S0 and spiral galaxies as a function of the cluster properties and
redshift. We find a large intrinsic scatter in the S0/E ratio, mostly related
to the cluster morphology. In particular, in our cluster sample, clusters with
a high concentration of ellipticals display a low S0/E ratio and, vice-versa,
low concentration clusters have a high S0/E. At the same time, the trend of the
morphological fractions and ratios with redshift clearly points to a
morphological evolution: as the redshift decreases, the S0 population tends to
grow at the expense of the spiral population, whereas the frequency of Es
remains almost constant. We also analyze the morphology-density (MD) relation
in our clusters and find that -similarly to higher redshift clusters- a good MD
relation exists in the high-concentration clusters, while it is absent in the
less concentrated clusters. Finally, the comparison of the MD relation in our
clusters with that of the D97 sample suggests that the transformation of
spirals into S0 galaxies becomes more efficient with decreasing local density.

</DOC>
<DOC>
<DOCNO> 40042 </DOCNO>
Precision Physics at the LHC


  A large number of precision measurements will be possible with the ATLAS and
CMS experiments at the CERN Large Hadron Collider (LHC). Examples from W
physics, Drell-Yan production of lepton pairs, Triple-Gauge Couplings,top
physics, Higgs and Supersymmetry are discussed.

</DOC>
<DOC>
<DOCNO> 68274 </DOCNO>
Double inflation in supergravity and the primordial black hole formation


  We study a double inflation model (a hybrid inflation + a new inflation) in
supergravity and discuss the formation of primordial black holes (PBHs) with
mass \sim 10^{-20}-10^{5}M_{\odot}. We find that in a wide range of parameter
space, we obtain PBHs which amount to \Omega \simeq 1, i.e., PBH dark matter.
Also, we find a set of inflation parameters which produces PBHs evaporating
now. Those PBHs may be responsible for antiproton fluxes observed by the BESS
experiment.

</DOC>
<DOC>
<DOCNO> 9389 </DOCNO>
Symmetry Based Properties of the Transition Metal Dichalcogenide


  The full geometrical symmetry groups (the line groups) of the monolayered,
2Hb and 3R polytypes of the inorganic MoS2 and WS2 micro- and nanotubes of
arbitrary chirality are found. This is used to find the coordinates of the
representative atoms sufficient to determine completely geometrical structure
of tubes. Then some physical properties which can be deduced from the symmetry
are discussed: electron band degeneracies, selection rules, general forms of
the second rank tensors and potentials, phonon spectra.

</DOC>
<DOC>
<DOCNO> 84937 </DOCNO>
Thin shell quantization in Weyl spacetime


  We study the problem of quantization of thin shells in a Weyl-Dirac theory by
deriving a Wheeler-DeWitt equation from the dynamics. Solutions are found which
have interpretations in both cosmology and particle physics.

</DOC>
<DOC>
<DOCNO> 150327 </DOCNO>
Noncommutative Yang-Mills from equivalence of star products


  It is shown that the transformation between ordinary and noncommutative
Yang-Mills theory as formulated by Seiberg and Witten is due to the equivalence
of certain star products on the D-brane world-volume.

</DOC>
<DOC>
<DOCNO> 83407 </DOCNO>
Towards a Theory of Cache-Efficient Algorithms


  We describe a model that enables us to analyze the running time of an
algorithm in a computer with a memory hierarchy with limited associativity, in
terms of various cache parameters. Our model, an extension of Aggarwal and
Vitter's I/O model, enables us to establish useful relationships between the
cache complexity and the I/O complexity of computations. As a corollary, we
obtain cache-optimal algorithms for some fundamental problems like sorting,
FFT, and an important subclass of permutations in the single-level cache model.
We also show that ignoring associativity concerns could lead to inferior
performance, by analyzing the average-case cache behavior of mergesort. We
further extend our model to multiple levels of cache with limited associativity
and present optimal algorithms for matrix transpose and sorting. Our techniques
may be used for systematic exploitation of the memory hierarchy starting from
the algorithm design stage, and dealing with the hitherto unresolved problem of
limited associativity.

</DOC>
<DOC>
<DOCNO> 84215 </DOCNO>
Tree Amplitudes and Two-loop Counterterms in D=11 Supergravity


  We compute the tree level 4-particle bosonic scattering amplitudes in D=11
supergravity. By construction, they are part of a linearized supersymmetry-,
coordinate- and 3-form gauge-invariant. While this on-shell invariant is
nonlocal, suitable SUSY-preserving differentiations turn it into a local one
with correct dimension to provide a natural lowest (two-loop) order counterterm
candidate. Its existence shows explicitly that no symmetries protect this
ultimate supergravity from the nonrenormalizability of its lower-dimensional
counterparts.

</DOC>
<DOC>
<DOCNO> 118613 </DOCNO>
The line of sight velocity distributions of simulated merger remnants


  We use Gauss-Hermite functions to study the line of sight velocity
distributions in simulated merger remnants. Our sample contains sixteen
remnants; eight produced by mergers between disk galaxies of equal mass and
eight produced by mergers between disk galaxies with mass ratios of 3:1. The
equal-mass mergers display a wide range of kinematic features, including
counterrotation at large radii, orthogonally rotating cores, and misaligned
rotational axes. Most of the unequal-mass remnants exhibit fairly regular
disk-like kinematics, although two have kinematics more typical of the
equal-mass remnants. Our results may be compared to observations of early type
objects, including ellipticals with misaligned kinematic axes, counterrotating
systems, and S0 galaxies.

</DOC>
<DOC>
<DOCNO> 99276 </DOCNO>
Conjugacy classes in maximal parabolic subgroups of general linear


  We compute conjugacy classes in maximal parabolic subgroups of the general
linear group. This computation proceeds by reducing to a ``matrix problem''.
Such problems involve finding normal forms for matrices under a specified set
of row and column operations. We solve the relevant matrix problem in small
dimensional cases. This gives us all conjugacy classes in maximal parabolic
subgroups over a perfect field when one of the two blocks has dimension less
than 6. In particular, this includes every maximal parabolic subgroup of
GL_n(k) for n < 12 and k a perfect field. If our field is finite of size q, we
also show that the number of conjugacy classes, and so the number of
characters, of these groups is a polynomial in $q$ with integral coefficients.

</DOC>
<DOC>
<DOCNO> 85326 </DOCNO>
Quintessence Energy and Dissipation


  The combined effect of a dissipative fluid and quintessence energy can
simultaneously drive an accelerated expansion phase at the present time and
solve the coincidence problem of our current Universe. A solution compatible
with the observed cosmic acceleration is succinctly presented.

</DOC>
<DOC>
<DOCNO> 39910 </DOCNO>
Measurement of J/Psi and Psi(2S) Polarization in ppbar Collisions at


  We have measured the polarization of J/Psi and Psi(2S) mesons produced in
p\bar{p} collisions at \sqrt{s} = 1.8 TeV, using data collected at CDF during
1992-95.
  The polarization of promptly produced J/Psi [Psi(2S)] mesons is isolated from
those produced in B-hadron decay, and measured over the kinematic range 4[5.5]
< P_T < 20 GeV/c and |y| < 0.6. For P_T \gessim 12 GeV/c we do not observe
significant polarization in the prompt component.

</DOC>
<DOC>
<DOCNO> 39990 </DOCNO>
Chiral Symmetry and the Parity-Violating $NN\pi$ Yukawa Coupling


  We construct the complete SU(2) parity-violating (PV) $\pi, N, \Delta$
interaction Lagrangian with one derivative, and calculate the chiral
corrections to the PV Yukawa $NN\pi$ coupling constant $h_\pi$ through ${\cal
O}(1/\Lambda_\chi^3)$ in the leading order of heavy baryon expansion. We
discuss the relationship between the renormalized $\hpi$, the measured value of
$\hpi$, and the corresponding quantity calculated microscopically from the
Standard Model four-quark PV interaction.

</DOC>
<DOC>
<DOCNO> 120260 </DOCNO>
Extracting Energy from Black Hole through Transition Region


  A new scenario for extracting energy from a Kerr black hole is proposed. With
magnetic field lines connecting plasma particles inside the ergosphere with
remote loads, the frame dragging twists the field lines so that energy and
angular momentum are extracted from the plasma particles. If the magnetic field
is strong enough, the energy extracted from the particles can be so large that
the particles have negative energy as they fall into the black hole. So
effectively the energy is extracted from the black hole.
  The particles inside the ergosphere can be continuously replenished with
accretion from a disk surrounding the black hole, so a transition region with
sufficient amount of plasma is formed between the black hole's horizon and the
inner edge of the disk. Thus the energy can be continuously extracted from the
black hole through the transition region. This may be the most efficient way
for extracting energy from a Kerr black hole: in principle almost all of the
rotational energy (up to $\approx 29%$ of the total energy of the black hole)
can be extracted.

</DOC>
<DOC>
<DOCNO> 151380 </DOCNO>
Stringy World Branes and Exponential Hierarchies


  We describe heterotic string and M-theory realizations of the Randall-Sundrum
(RS) scenario with $\cx N=2$ and $\cx N=1$ supersymmetry in the bulk.
Supersymmetry can be broken only on the world brane, a scenario that has been
proposed to account for the smallness of the cosmological constant. An
interesting prediction from string duality is the generation of a warp factor
for conventional type II Calabi--Yau 3-fold compactifications. On the other
hand we argue that an assumption that is needed in the RS explanation of the
hierarchy is hard to satisfy in the string theory context.

</DOC>
<DOC>
<DOCNO> 7735 </DOCNO>
Phase transitions in generalized chiral or Stiefel's models


  We study the phase transition in generalized chiral or Stiefel's models using
Monte Carlo simulations. These models are characterized by a breakdown of
symmetry O(N)/O(N-P). We show that the phase transition is clearly first order
for N >= 3 when P=N and P=N-1, contrary to predictions based on the
Renormalization Group in 4-\epsilon expansion but in agreement with a recent
non perturbative Renormalization Group approach.

</DOC>
<DOC>
<DOCNO> 123219 </DOCNO>
The Cuspy LINER Nucleus of the S0/a Galaxy NGC 2681


  The nucleus of the bulge-dominated, multiply-barred S0/a galaxy NGC 2681 is
studied in detail, using high resolution Hubble Space Telescope FOC and NICMOS
imaging and FOS spectroscopy. The ionised gas central velocity dispersion is
found to increase by a factor ~2 when narrowing the aperture from R~1.5"
(ground) to R~0.1" (FOS). Dynamical modeling of these velocity dispersions
suggests that NGC 2681 does host a supermassive black hole (BH) for which one
can estimate a firm mass upper limit M_BH < 6*10^7 Solar Masses. This upper
limit is consistent with the relation between the central BH mass and velocity
dispersion M_BH - sigma known for other galaxies. The emission line ratios
place the nucleus of NGC 2681 among LINERs. It is likely that the emission line
region comes from a rather mild, but steady, feeding of gas to the central BH
in this galaxy. The inner stellar population lacks any measurable color
gradient (to a radius of 0.6 kpc) from the infrared to the ultraviolet,
consistently with FOC, FOS and IUE data, all indicating that this system
underwent a starburst ~1 Gyr ago that encompassed its whole interior, down to
its very center. The most likely source of such a widely-distributed starburst
is the dumping of tidally-extruded gas from a galaxy neighbor. If so, then NGC
2681 can be considered as the older brother of M82, seen face-on as opposed to
the edge-on view we have for M82.

</DOC>
<DOC>
<DOCNO> 84243 </DOCNO>
General Relativistic Stars : Polytropic Equations of State


  In this paper, the gravitational field equations for static spherically
symmetric perfect fluid models with a polytropic equation of state,
$p=k\rho^{1+1/n}$, are recast into two complementary 3-dimensional {\it
regular} systems of ordinary differential equations on compact state spaces.
The systems are analyzed numerically and qualitatively, using the theory of
dynamical systems. Certain key solutions are shown to form building blocks
which, to a large extent, determine the remaining solution structure. In one
formulation, there exists a monotone function that forces the general
relativistic solutions towards a part of the boundary of the state space that
corresponds to the low pressure limit. The solutions on this boundary describe
Newtonian models and thus the relationship to the Newtonian solution space is
clearly displayed. It is numerically demonstrated that general relativistic
models have finite radii when the polytropic index $n$ satisfies $0\leq n
\lesssim 3.339$ and infinite radii when $n\geq 5$. When $3.339\lesssim n<5$,
there exists a 1-parameter set of models with finite radii and a finite number,
depending on $n$, with infinite radii.

</DOC>
<DOC>
<DOCNO> 8428 </DOCNO>
Gap deformation and classical wave localization in disordered


  By using two ab initio numerical methods we study the effects that disorder
has on the spectral gaps and on wave localization in two-dimensional photonic
band gap materials. We find that there are basically two different responses
depending on the lattice realization (solid dielectric cylinders in air or vise
versa), the wave polarization, and the particular form under which disorder is
introduced. Two different pictures for the photonic states are employed, the
``nearly free'' photon and the ``strongly localized'' photon. These originate
from the two different mechanisms responsible for the formation of the spectral
gaps, ie. multiple scattering and single scatterer resonances, and they
qualitatively explain our results.

</DOC>
<DOC>
<DOCNO> 102389 </DOCNO>
Morse theory, Milnor fibers and minimality of hyperplane arrangements


  Through the study of Morse theory on the associated Milnor fiber, we show
that complex hyperplane arrangement complements are minimal. That is, the
complement of a complex hyperplane arrangement has the homotopy type of a CW
complex in which the number of p-cells equals the p-th betti number.

</DOC>
<DOC>
<DOCNO> 13875 </DOCNO>
Adsorption of a random heteropolymer at a potential well revisited:


  The adsorption of an ideal heteropolymer loop at a potential point well is
investigated within the frameworks of a standard random matrix theory. On the
basis of semi-analytical/semi-numerical approach the histogram of transition
points for the ensemble of quenched heteropolymer structures with bimodal
symmetric distribution of types of chain's links is constructed. It is shown
that the sequences having the transition points in the tail of the histogram
display the correlations between nearest-neighbor monomers.

</DOC>
<DOC>
<DOCNO> 40337 </DOCNO>
Angular Signatures for Galactic Halo WIMP Scattering in Direct


  Angular Sensitivity can provide a key additional tool which might allow
unambiguous separation of a signal due to Galactic halo WIMPs from other
possible backgrounds in direct detectors. We provide a formalism which allows a
calculation of the expected angular distribution of events in terrestrial
detectors with angular sensitivity for any incident distribution of Galactic
halo dark matter. This can be used as an input when studying the sensitivity of
specific detectors to halo WIMPs. We utilize this formalism to examine the
expected signature for WIMP dark matter using a variety of existing analytic
halo models in order to explore how uncertainty in the Galactic halo
distribution impact on the the event rates that may be required to separate a
possible WIMP signal from other terrestrial backgrounds. We find that as few as
30 events might be required to disentangle the signal from backgrounds if the
WIMP distribution resembles an isothermal sphere distribution. On the other
hand, for certain halo distributions, even detectors with fine scale resolution
may require in excess of a 100-400 events to distinguish a WIMP signal from
backgrounds using angular sensitivity. We also note that for finite thresholds
the different energy dependence of spin-dependent scattering cross sections may
require a greater number of events to discern a WIMP signal than for spin
independent interactions. Finally, we briefly describe ongoing studies aimed at
developing strategies to better exploit angular signatures, and the use of
N-body simulations to better model the expected halo distribution in predicting
the expected signature for direct WIMP detectors.

</DOC>
<DOC>
<DOCNO> 40285 </DOCNO>
Asymmetries in the production of lambda zero, cascade minus, and omega


  Using data from Fermilab fixed-target experiment E791, we have measured
particle-antiparticle production asymmetries for lambda zero, cascade minus,
and omega minus hyperons in pi minus-nucleon interactions at 500 GeV/c. The
asymmetries are measured as functions of Feynman-x (x_F) and pt^2 over the
ranges of -0.12 GE x_F LE 0.12 and 0 GE pt^2 LE 4 (GeV/c)^2. We find
substantial asymmetries, even at x_F = 0. We also observe leading-particle-
type asymmetries which qualitatively agree with theoretical predictions.

</DOC>
<DOC>
<DOCNO> 68816 </DOCNO>
Phases and Residual Gauge Symmetries of Higgs Models


  After elimination of the redundant variables, gauge theories may still
exhibit symmetries associated with the gauge fields. The role of these residual
gauge symmetries is discussed within the Abelian Higgs model and the
Georgi-Glashow model. In the different phases of these models, these symmetries
are realized differently. The characteristics of emergence and disappearance of
the symmetries are studied in detail and the implications for the dynamics in
Coulomb, Higgs, and confining phases are discussed.

</DOC>
<DOC>
<DOCNO> 152525 </DOCNO>
Extended Hamiltonian Formalism of the Pure Space-Like Axial Gauge


  We demonstrate that pure space-like axial gauge quantizations of gauge fields
can be constructed in ways which are free from infrared divergences. We begin
by constructing an axial gauge formulation in auxiliary coordinates:
$x^+=x^0\sin{\theta}+x^1\cos{\theta}, x^-=x^0\cos{\theta}-x^1\sin{\theta}$. For
\theta less than \pi\over 4 we can take $x^-$ as the evolution parameter and
construct a traditional canonical formulation of the temporal gauge Schwinger
model in which residual gauge fields dependent only on $x^+$ are static
canonical variables. Then we extrapolate the temporal gauge operator solution
into the axial region, \theta > \pi \over 4, where $x^+$ is taken as the
evolution parameter. In the axial region we find that we have to change
representations of the residual gauge fields from one realizing the PV
prescription to one realizing the ML prescription in order for the infrared
divergences resulting from $({\partial}_-)^{-1}$ to be canceled by
corresponding ones resulting from the inverse of the hyperbolic Laplace
operator. Finally, by taking the limit ${\theta}\to\frac{\pi}{2}-0$ we obtain
an operator solution and the Hamiltonian of the axial gauge (Coulomb gauge
)Schwinger model in ordinary coordinates. That solution includes auxiliary
fields and the representation space is of indefinite metric, providing further
evidence that ``physical'' gauges are no more physical than ``unphysical''
gauges.

</DOC>
<DOC>
<DOCNO> 121702 </DOCNO>
On the Mass-Donating Star in GRS 1915+105


  We present an analysis of constraints on the companion mass for the Galactic
microquasar GRS 1915+105. Using the known inclination angle and stability of
the jet axis, we can rule out massive ($M_s \ga 3 M_{\sun}$) companions with
orbital axes not aligned with the jet axis. For an aligned orbital axis, we
constrain the ratio of the stellar radius to the binary semi-major axis to be
$R_s/a <0.342$, based on the lack of X-ray eclipses. We then show that these
constraints together with the X-ray luminosity, approximate black hole mass,
and observations of the X-ray absorbing column density towards GRS 1915+105
rule out accretion via stellar wind from a massive companion, implying that
accretion occurs via Roche-lobe overflow. In that case, the constraint on
$R_s/a$ rules out any companion with $M_s > 19.4 M_{\sun}$ for a black hole
mass of $M_{BH} \simeq 30 M_{\sun}$. The lack of significant X-ray reprocessing
in the infrared from GRS 1915+105 also provides constraints on the mass and
temperature range of a Roche-lobe-filling mass donor.

</DOC>
<DOC>
<DOCNO> 179042 </DOCNO>
Model-independent definition and determination of electromagnetic


  A theoretical method for the systematic definition and determination of
Cartesian and spherical electromagnetic (onshell) formfactors and multipole
moments for particles or composite systems from electromagnetic Breit-frame
current distributions is presented. The method presented is free of sign
ambiguities and is not based on the underlying analytical substructure of the
electromagnetic current distributions. By construction the method contains all
higher order momentum derivative terms within the definition of electromagnetic
formfactors and multipole moments, which are not taken into account in a lot of
existing theoretical calculations.

</DOC>
<DOC>
<DOCNO> 102315 </DOCNO>
P^2-reducing and toroidal Dehn fillings


  We study the situation where we have two exceptional Dehn fillings on a given
hyperbolic 3-manifold. We consider two cases that one filling creates a
projective plane, and the other creates an essential torus or a Klein bottle,
and give the best possible upper bound on the distance between two fillings for
each case.

</DOC>
<DOC>
<DOCNO> 121723 </DOCNO>
ASCA Observation of an X-Ray-Luminous Active Nucleus in Markarian 231


  We have obtained a moderately long (100 kilosecond) ASCA observation of the
Seyfert 1 galaxy Markarian 231, the most luminous of the local ultraluminous
infrared galaxy (ULIRG) population. In the best-fitting model we do not see the
X-ray source directly; the spectrum consists of a scattered power-law component
and a reflection component, both of which have been absorbed by a column N_H
\approx 3 X 10^(22)/cm^2. About 3/4 of the observed hard X-rays arise from the
scattered component, reducing the equivalent width of the iron K alpha line.
The implied ratio of 1-10 keV X-ray luminosity to bolometric luminosity,
L_x/L_bol \sim 2%, is typical of Sy 1 galaxies and radio-quiet QSOs of
comparable bolometric luminosities, and indicates that the bolometric
luminosity is dominated by the AGN. Our estimate of the X-ray luminosity also
moves Mrk 231 in line with the correlations found for AGN with extremely strong
Fe II emission. A second source separated by about 2 arcminutes is also clearly
detected, and contributes about 25% of the total flux.

</DOC>
<DOC>
<DOCNO> 122217 </DOCNO>
Measurement of the Cosmic Ray Energy Spectrum and Composition from


  We study the spectrum and average mass composition of cosmic rays with
primary energies between 10^{17} eV and 10^{18} eV using a hybrid detector
consisting of the High Resolution Fly's Eye (HiRes) prototype and the MIA muon
array. Measurements have been made of the change in the depth of shower maximum
as a function of energy. A complete Monte Carlo simulation of the detector
response and comparisons with shower simulations leads to the conclusion that
the cosmic ray intensity is changing f rom a heavier to a lighter composition
in this energy range. The spectrum is consistent with earlier Fly's Eye
measurements and supports the previously found steepening near 4 \times 10^{17}
eV .

</DOC>
<DOC>
<DOCNO> 13980 </DOCNO>
Irreversibble Bimolecular Reactions of Langevin Particles


  The reaction A+B --> B is studied when the reactants diffuse in phase space,
i.e. their dynamics is described by the Langevin equation. The steady-state
rate constants are calculated for both the target (static A and mobile B's) and
trapping (mobile A and static B's) problems when the reaction is assumed to
occur at the first contact. For Brownian dynamics (i.e., ordinary diffusion),
the rate constant for both problems is a monotonically decreasing function of
the friction coefficient $\gamma$. For Langevin dynamics, however, we find that
the steady-state rate constant exhibits a turnover behavior as a function of
$\gamma$ for the trapping problem but not for the target problem. This turnover
is different from the familiar Kramers' turnover of the rate constant for
escape from a deep potential well because the reaction considered here is an
activationless process.

</DOC>
<DOC>
<DOCNO> 117746 </DOCNO>
X-Ray Afterglows of Gamma-Ray Bursts


  The afterglow emission has become the main stream of Gamma-Ray burst research
since its discovery three years ago. With the distance-scale enigma solved, the
study of the late-time GRB emission is now the most promising approach to
disclose the origin of these explosions and their relationship with the
environment of the host galaxy in the early phase of the Universe. In this
contribution I will review X-ray observations and their implication on our
undertstanding on the GRB phenomenon. These measurements are providing a direct
probe into the nature of the progenitor and a measurement of the GRB beaming
properties, crucial to establish the total energy output. Some evidence of iron
lines connects the GRB explosion with massive progenitors, thence with
star-forming regions. Furthermore a comparison of the spectral properties with
the temporal evolution indicates that the fireball expansion should not be - on
average - highly collimated, with a jet angle $>10 \deg$.

</DOC>
<DOC>
<DOCNO> 102908 </DOCNO>
A sample-paths approach to noise-induced synchronization: Stochastic


  Additive white noise may significantly increase the response of bistable
systems to a periodic driving signal. We consider two classes of double-well
potentials, symmetric and asymmetric, modulated periodically in time with
period $1/\eps$, where $\eps$ is a moderately (not exponentially) small
parameter. We show that the response of the system changes drastically when the
noise intensity $\sigma$ crosses a threshold value. Below the threshold, paths
are concentrated near one potential well, and have an exponentially small
probability to jump to the other well. Above the threshold, transitions between
the wells occur with probability exponentially close to 1/2 in the symmetric
case, and exponentially close to 1 in the asymmetric case. The transition zones
are localised in time near the points of minimal barrier height. We give a
mathematically rigorous description of the behaviour of individual paths, which
allows us, in particular, to determine the power-law dependence of the critical
noise intensity on $\eps$ and on the minimal barrier height, as well as the
asymptotics of the transition and non-transition probabilities.

</DOC>
<DOC>
<DOCNO> 67675 </DOCNO>
Matter effects on neutrino oscillations in gravitational and magnetic


  When neutrinos propagate in a background, their gravitational couplings are
modified by their weak interactions with the particles in the background. In a
medium that contains electrons but no muons or taons, the matter-induced
gravitational couplings of neutrinos are different for the various neutrino
flavors, and they must be taken into account in describing the phenomena
associated with the neutrino oscillations in the presence of strong
gravitational fields. Here we incorporate those couplings in that description,
including also the effects of a magnetic field, and consider the implications
that they have for the emission of high energy neutrinos in the vicinity of
Active Galactic Nuclei.

</DOC>
<DOC>
<DOCNO> 85189 </DOCNO>
Gravitational waves and spinning test particles


  The motion of a classical spinning test particle in the field of a weak plane
gravitational wave is studied. It is found that the characteristic dimensions
of the particle's orbit is sensitive to the ratio of the spin to the mass of
the particle. The results are compared with the corresponding motion of a
particle without spin.

</DOC>
<DOC>
<DOCNO> 13570 </DOCNO>
Excitons in T-shaped quantum wires


  We calculate energies, oscillator strengths for radiative recombination, and
two-particle wave functions for the ground state exciton and around 100 excited
states in a T-shaped quantum wire. We include the single-particle potential and
the Coulomb interaction between the electron and hole on an equal footing, and
perform exact diagonalisation of the two-particle problem within a finite basis
set. We calculate spectra for all of the experimentally studied cases of
T-shaped wires including symmetric and asymmetric GaAs/Al$_{x}$Ga$_{1-x}$As and
In$_{y}$Ga$_{1-y}$As/Al$_{x}$Ga$_{1-x}$As structures. We study in detail the
shape of the wave functions to gain insight into the nature of the various
states for selected symmetric and asymmetric wires in which laser emission has
been experimentally observed. We also calculate the binding energy of the
ground state exciton and the confinement energy of the 1D quantum-wire-exciton
state with respect to the 2D quantum-well exciton for a wide range of
structures, varying the well width and the Al molar fraction $x$. We find that
the largest binding energy of any wire constructed to date is 16.5 meV. We also
notice that in asymmetric structures, the confinement energy is enhanced with
respect to the symmetric forms with comparable parameters but the binding
energy of the exciton is then lower than in the symmetric structures. For
GaAs/Al$_{x}$Ga$_{1-x}$As wires we obtain an upper limit for the binding energy
of around 25 meV in a 10 {\AA} wide GaAs/AlAs structure which suggests that
other materials must be explored in order to achieve room temperature
applications. There are some indications that
In$_{y}$Ga$_{1-y}$As/Al$_{x}$Ga$_{1-x}$As might be a good candidate.

</DOC>
<DOC>
<DOCNO> 119289 </DOCNO>
The synthesis of the light Mo and Ru isotopes: how now, no need for an


  The most detailed calculations of the p-process call for its development in
the O/Ne layers of Type II supernovae. In spite of their overall success in
reproducing the solar system content of p-nuclides, they suggest a significant
underproduction of the light Mo and Ru isotopes. On grounds of a model for the
explosion of a 25 solar mass star with solar metallicity, we demonstrate that
this failure might just be related to the uncertainties left in the rate of the
22Ne(alpha,n)25Mg neutron producing reaction. The latter indeed have a direct
impact on the distribution of the s-process seeds for the p-process.

</DOC>
<DOC>
<DOCNO> 117936 </DOCNO>
Chemical and dynamical evolution in gas-rich dwarf galaxies


  We study the effect of a single, instantaneous starburst in a gas-rich dwarf
galaxy on the dynamical and chemical evolution of its interstellar medium. We
consider the energetic input and the chemical yields originating from SNeII,
SNeIa and intermediate-mass stars. We find that a galaxy resembling IZw18
develops a galactic wind carrying out mostly the metal-rich gas. The various
metals are lost differentially and the metals produced by the SNeIa are lost
more efficiently than the others. As a consequence, we find larger
[$\alpha$/Fe] ratios for the gas inside the galaxy than for the gas leaving the
galaxy. Finally we find that a single burst occurring in primordial gas
(without pre-enrichment), gives chemical abundances and dynamical structures in
good agreement with what observed in IZw18 after $\sim$ 29 Myr from the
beginning of star formation.

</DOC>
<DOC>
<DOCNO> 85498 </DOCNO>
Gravitation in Flat Spacetime


  A special-relativistic scalar-vector theory of gravitation is presented which
mimics an important class of solutions of Einstein's gravitational field
equations. The theory includes solutions equivalent to Schwarzschild, Kerr,
Reissner-Nordstroem, and Friedman metrics as well as to gravitational waves. In
fact, all the empirical tests until now due to general relativity can be
explained within this flat spacetime theory.

</DOC>
<DOC>
<DOCNO> 85290 </DOCNO>
Classical and quantum equivalence principle in terms of the path group


  A natural mapping of paths in a curved space onto the paths in the
corresponding (tangent) flat space may be used to reduce the curved-space-time
path integral to the flat-space-time path integral. The dynamics of the
particle in a curved space-time is expressed then in terms of an integral over
paths in the flat (Minkowski) space-time. This may be called quantum
equivalence principle. Contrary to the known DeWitt's definition of a
curved-space path integral, the present definition leads to the covariant
equation of motion without a scalar curvature term. The reduction of a
curved-space path integral to the flat-space path integral may be expressed in
terms of a representation of the path group. With the help of this
representation all the results may be generalized to the case of an arbitrary
external field.

</DOC>
<DOC>
<DOCNO> 39648 </DOCNO>
Test Result of Time-Of-Propagation Cherenkov Counter


  A new concept concerning Cherenkov detector for particle identification by
means of measuring both the Time-of-Propagation (TOP) and horizontal emission
angle ($\Phi$) of Cherenkov photons is described here. Some R&D works are also
reported.

</DOC>
<DOC>
<DOCNO> 69266 </DOCNO>
D Branes and Textures


  We examine the flavor structure of the trilinear superpotential couplings
which can result from embedding the Standard Model within D brane sectors in
Type IIB orientifold models, which are examples within the Type I string
framework. We find in general that the allowed flavor structures of the Yukawa
coupling matrices to leading order are given by basic variations on the
"democratic" texture ansatz. In certain interesting cases, the Yukawa couplings
have a novel structure in which a single right-handed fermion couples
democratically at leading order to three left-handed fermions. We discuss the
viability of such a ``single right-handed democracy'' in detail; remarkably,
even though there are large mixing angles in the u,d sectors separately, the
CKM mixing angles are small. The analysis demonstrates the ways in which the
Type I superstring framework can provide a rich setting for investigating novel
resolutions to the flavor puzzle.

</DOC>
<DOC>
<DOCNO> 39618 </DOCNO>
On the Parameterization of the Longitudinal Hadronic Shower Profiles in


  The extension of the longitudinal hadronic shower profile parameterization
which takes into account non-compensations of calorimeters and the algorithm of
the longitudinal hadronic shower profile curve making for a combined
calorimeter are suggested. The proposed algorithms can be used for data
analysis from modern combined calorimeters like in the ATLAS detector at the
LHC.

</DOC>
<DOC>
<DOCNO> 121842 </DOCNO>
H-alpha Velocity Fields of Normal Spiral Disks


  We present H-alpha velocity fields for a sample of nearly face--on spiral
galaxies observed with DensePak on the WIYN telescope. We combine kinematic
inclinations and position angles measured from these data with photometric
inclinations and position angles measured from I-band images to show that
spiral disks are intrinsically non-circular.

</DOC>
<DOC>
<DOCNO> 117606 </DOCNO>
Solar cycle variation in solar f-mode frequencies and radius


  Using data from the Global Oscillation Network Group (GONG) covering the
period from 1995 to 1998, we study the change with solar activity in solar
f-mode frequencies. The results are compared with similar changes detected from
the Michelson Doppler Imager (MDI) data. We find variations in f-mode
frequencies which are correlated with solar activity indices. If these changes
are due to variation in solar radius then the implications are that the solar
radius decreases by about 5 km from minimum to maximum activity.

</DOC>
<DOC>
<DOCNO> 169769 </DOCNO>
Perturbative expansion for master equation and it applications


  We construct generally applicable small-loss rate expansions for the density
operator of an open system. Successive terms of those expansions yield
characteristic loss rates for dissipation processes. Three applications are
presented in order to give further insight into the context of those
expansions. The first application, of a two-level atom coupling to a bosonic
environment, shows the procedure and the advantage of the expansion, whereas
the second application that consists of a single mode field in a cavity with
linewidth $\kappa$ due to partial transmission through one mirror illustrates a
practical use of those expansions in quantum measurements, and the third one,
for an atom coupled to modes of a lossy cavity shows the another use of the
perturbative expansion.

</DOC>
<DOC>
<DOCNO> 69480 </DOCNO>
Tritium Beta Decay, Neutrino Mass Matrices and Interactions Beyond the


  The interference of charge-changing interactions, weaker than the V-A
Standard Model (SM) interaction and having a different Lorentz structure, with
that SM interaction, can, in principle, produce effects near the end point of
the Tritium beta decay spectrum which are of a different character from those
produced by the purely kinematic effect of neutrino mass expected in the
simplest extension of the SM. We show that the existence of more than one mass
eigenstate can lead to interference effects at the end point that are stronger
than those occurring over the entire spectrum. We discuss these effects both
for the special case of Dirac neutrinos and the more general case of Majorana
neutrinos and show that, for the present precision of the experiments, one
formula should suffice to express the interference effects in all cases.
Implications for "sterile" neutrinos are noted.

</DOC>
<DOC>
<DOCNO> 9604 </DOCNO>
Anomalous diffusion through coupling to a fractal environment:


  Two models for quantum Brownian motion - the Oscillator Bath (OB) model and
the Random-Band-Matrix (RBM) model - are compared and a relation between the
spectral density function I(w) and the variance (Vab)^2 is established. The
extension to a fractal environment is then considered and the microscopic
origin of anomalous diffusion is discussed. In particular, it is shown that the
asymptotic behavior of the normalized velocity auto-correlation function (VACF)
is entirely determined by the band form factor. This allows for a microscopic
derivation of the "whip-back" effect.

</DOC>
<DOC>
<DOCNO> 119191 </DOCNO>
O VI and Multicomponent H I Absorption Associated with a Galaxy Group in


  We report the discovery of an O VI absorption system at z(abs) = 0.14232 in a
high resolution FUV spectrum of PG0953+415 obtained with the Space Telescope
Imaging Spectrograph (STIS). Both lines of the O VI 1032, 1038 doublet and
multicomponent H I Lya absorption are detected, but the N V doublet and the
strong lines of C II and Si III are not apparent. We examine the ionization
mechanism of the O VI absorber and find that while theoretical considerations
favor collisional ionization, it is difficult to observationally rule out
photoionization. If the absorber is collisionally ionized, it may not be in
equilibrium due to the rapid cooling of gas in the appropriate temperature
range. Non-equilibrium collisionally ionized models are shown to be consistent
with the observations. A WIYN survey of galaxy redshifts near the sight line
has revealed a galaxy at a projected distance of 395 kpc separated by ~130 km/s
from this absorber, and three additional galaxies are found within 130 km/s of
this redshift with projected separations ranging from 1.0 Mpc to 3.0 Mpc.
Combining the STIS observations of PG0953+415 with previous high S/N GHRS
observations of H1821+643, we derive a large number of O VI absorbers per unit
redshift, dN/dz ~20. We use this sample to obtain a first estimate of the
cosmological mass density of the O VI systems at z ~ 0. If further observations
confirm the large dN/dz derived for the O VI systems, then these absorbers
trace a significant reservoir of baryonic matter at low redshift.

</DOC>
<DOC>
<DOCNO> 102507 </DOCNO>
The Coppersmith-Tetali-Winkler Identity for Mechanical Systems


  Using a mixture of linear algebra and statics, we derive what can be viewed
as a slight generalization of the Coppersmith-Tetali-Winkler Identity
$H(i,j)+H(j,k)+H(k,i)=H(j,i)+H(k,j)+H(i,k)$ for hitting times of a random walk.

</DOC>
<DOC>
<DOCNO> 116749 </DOCNO>
Continuation of the Fermion-Number Operator and the Puzzle of Families


  An "analytic continuation" of a Hermitian matrix representing the
conventional fermion-number operator, leads to a new, and unconventional,
internal description of quarks and leptons. This phenomenological description,
unlike the conventional standard-model description, is capable of explaining,
among other things, why there are just three families of quarks and leptons.
These facts provide indirect evidence that the analytic continuation in
question somehow reflects physics at the Planck level where flavor
degrees-of-freedom presumably originate.

</DOC>
<DOC>
<DOCNO> 83142 </DOCNO>
PAL: Pertinence Action Language


  The current document contains a brief description of a system for Reasoning
about Actions and Change called PAL (Pertinence Action Language) which makes
use of several reasoning properties extracted from a Temporal Expert Systems
tool called Medtool.

</DOC>
<DOC>
<DOCNO> 116699 </DOCNO>
The Architecture of Idiotypic Networks: Percolation and Scaling


  We investigate a model where idiotypes (characterizing B-lymphocytes and
antibodies of an immune system) and anti-idiotypes are represented by
complementary bitstrings of a given length d allowing for a number of
mismatches (matching rules). In this model, the vertices of the hypercube in
dimension d represent the potential repertoire of idiotypes. A random set of
(with probability p) occupied vertices corresponds to the expressed repertoire
of idiotypes at a given moment. Vertices of this set linked by the above
matching rules build random clusters. We give a structural and statistical
characterisation of these clusters - or in other words - of the architecture of
the idiotypic network. Increasing the probability p one finds at a critical p a
percolation transition where for the first time a large connected graph occures
with probability one. Increasing p further, there is a second transition above
which the repertoire is complete in the sense that any newly introduced
idiotype finds a complementary anti-idiotype. We introduce structural
characteristics such as the mass distributions and the fragmentation rate for
random clusters, and determine the scaling behaviour of the cluster size
distribution near the percolation transition, including finite size
corrections. We find that slightly above the percolation transition the large
connected cluster (the central part of the idiotypic network) consists
typically of one highly connected part and a number of weakly connected
constituents and coexists with a number of small, isolated clusters. This is in
accordance with the picture of a central and a peripheral part of the idiotypic
network and gives some support to idealized architectures of the central part
used in recent dynamical mean field models.

</DOC>
<DOC>
<DOCNO> 121561 </DOCNO>
Medium Effects in Neutrino Cooling of Neutron Stars


  This review demonstrates that neutrino emission from dense hadronic component
in neutron stars is subject of strong modifications due to collective effects
in the nuclear matter. With the most important in-medium processes incorporated
in the cooling code an overall agreement with available soft $X$ ray data can
be easily achieved. With these findings so called "standard" and "non-standard"
cooling scenarios are replaced by one general "nuclear medium cooling scenario"
which relates slow and rapid neutron star coolings to the star masses (interior
densities). In-medium effects take important part also at early hot stage of
neutron star evolution decreasing the neutrino opacity for less massive and
increasing for more massive neutron stars. A formalism for calculation of
neutrino radiation from nuclear matter is presented that treats on equal
footing one-nucleon and multiple-nucleon processes as well as reactions with
resonance bosons and condensates.

</DOC>
<DOC>
<DOCNO> 117425 </DOCNO>
CCD Photometry of the Globular Cluster Omega Centauri. I. Metallicity of


  We present new measurements of the metallicity of 131 RR Lyrae stars in the
globular cluster Omega Centauri, using the hk index of the Caby photometric
system. The hk method has distinct advantages over Delta-S and other techniques
in determining the metallicity of RR Lyrae stars, and has allowed us to obtain
the most complete and homogeneous metallicity data to date for the RR Lyrae
stars in this cluster. For RR Lyrae stars in common with the Delta-S
observations of Butler et al. (1978) and Gratton et al. (1986), we have found
that our metallicities, [Fe/H](hk), deviate systematically from their Delta-S
metallicity, while our [Fe/H](hk) for well observed field RRab stars are
consistent with previous spectroscopic measurements. We conclude that this is
due to the larger errors associated with the previous Delta-S observations for
this cluster. The Mv(RR) - [Fe/H] and period-shift - [Fe/H] relations obtained
from our new data are consistent with the evolutionary models predicted by Lee
(1991), confirming that the luminosity of RR Lyrae stars depends on
evolutionary status as well as metallicity. Using the period - amplitude
diagram, we have also identified highly evolved RRab stars in the range of -1.9
< [Fe/H] < -1.5, as predicted from the synthetic horizontal-branch models.

</DOC>
<DOC>
<DOCNO> 70048 </DOCNO>
Dynamical Cosmological Constant from A Very Recent Phase Transition


  Observation indicates that the expansion of the Universe is accelerating and
favours a dynamical cosmological constant, \Lambda(t). We consider the
possibility that this is due to a scalar field which has undergone a very
recent phase transition. We study a simple class of model, corresponding to a
\phi^4 potential with a time-dependent mass squared term. For the models
considered the phase transition occurs at a red shift z \leq 1.2. The evolution
of the equation of state \omega_{\phi} and energy density \rho_{\phi} with time
is distinct from existing dynamical \Lambda models based on slowly rolling
fields, with \omega_{\phi} and \rho_{\phi} rapidly changing in a characteristic
way following the transition. The \phi energy density is composed of a
time-dependent vacuum energy and coherently oscillating condensate component
with a negative pressure. The condensate component will collapse to form
non-topological soliton lumps, '\phi-axitons', which smoothly populate the
Universe.

</DOC>
<DOC>
<DOCNO> 116808 </DOCNO>
On electromagnetic induction


  A general law for electromagnetic induction phenomena is derived from Lorentz
force and Maxwell equation connecting electric field and time variation of
magnetic field. The derivation provides with a unified mathematical treatment
the statement according to which electromagnetic induction is the product of
two independent phenomena: time variation of magnetic field and effects of
magnetic field on moving charges. The general law deals easily-without ad hoc
assumptions-with typical cases usually considered as exceptions to the flux
rule and contains the flux rule as a particular case.

</DOC>
<DOC>
<DOCNO> 39649 </DOCNO>
Atmospheric Neutrinos


  The results of experiments on atmospheric neutrinos are summarized, with the
important exception of Superkamiokande. The main emphasis is given to the
Soudan-2 and MACRO experiments. Both experiments observe atmospheric neutrino
anomalies in agreement with nu_mu-->> nu_tau oscillations with maximum mixing.
The nu_mu-->> nu_sterile oscillation is disfavored by the MACRO experiment.

</DOC>
<DOC>
<DOCNO> 70947 </DOCNO>
Lifetime pattern of heavy hadrons


  We discuss the lifetime pattern of weakly decaying heavy hadrons.

</DOC>
<DOC>
<DOCNO> 118116 </DOCNO>
High-resolution simulations and visualization of protoplanetary disks


  A problem of mass flow in the immediate vicinity of a planet embedded in a
protoplanetary disk is studied numerically in two dimensions. Large differences
in temporal and spatial scales involved suggest that a specialized
discretization method for solution of hydrodynamical equations may offer great
savings in computational resources, and can make extensive parameter studies
feasible. Preliminary results obtained with help of Adaptive Mesh Refinement
technique and high-order explicit Eulerian solver are presented. This
combination of numerical techniques appears to be an excellent tool which
allows for direct simulations of mass flow in vicinity of the accretor at
moderate computational cost. In particular, it is possible to resolve the
surface of the planet and to model the process of planet growth with minimal
set of assumptions. Some issues related to visualization of the results and
future prospects are discussed briefly.

</DOC>
<DOC>
<DOCNO> 122199 </DOCNO>
Reproducing the observed Cosmic microwave background anisotropies with


  During the last years it has become clear that global O(N) defects and U(1)
cosmic strings do not lead to the pronounced first acoustic peak in the power
spectrum of anisotropies of the cosmic microwave background which has recently
been observed to high accuracy. Inflationary models cannot easily accommodate
the low second peak indicated by the data. Here we construct causal scaling
seed models which reproduce the first and second peak. Future, more precise CMB
anisotropy and polarization experiments will however be able to distinguish
them from the ordinary adiabatic models.

</DOC>
<DOC>
<DOCNO> 83455 </DOCNO>
Chip-level CMP Modeling and Smart Dummy for HDP and Conformal CVD Films


  Chip-level CMP modeling is investigated to obtain the post-CMP film profile
thickness across a die from its design layout file and a few film deposition
and CMP parameters. The work covers both HDP and conformal CVD film. The
experimental CMP results agree well with the modeled results. Different
algorithms for filling of dummy structure are compared. A smart algorithm for
dummy filling is presented, which achieves maximal pattern-density uniformity
and CMP planarity.

</DOC>
<DOC>
<DOCNO> 7952 </DOCNO>
Structure and rheology of binary mixtures in shear flow


  Results are presented for the phase separation process of a binary mixture
subject to an uniform shear flow quenched from a disordered to a homogeneous
ordered phase. The kinetics of the process is described in the context of the
time-dependent Ginzburg-Landau equation with an external velocity term. The
large-N approximation is used to study the evolution of the model in the
presence of a stationary flow and in the case of an oscillating shear.
  For stationary flow we show that the structure factor obeys a generalized
dynamical scaling. The domains grow with different typical lengthscales $R_x$
and $R_\perp$ respectively in the flow direction and perpendicularly to it. In
the scaling regime $R_\perp \sim t^{\alpha_\perp}$ and $R_x \sim \gamma
t^{\alpha_x}$ (with logarithmic corrections), $\gamma $ being the shear rate,
with $\alpha_x=5/4$ and $\alpha_\perp =1/4$. The excess viscosity $\Delta \eta$
after reaching a maximum relaxes to zero as $\gamma ^{-2}t^{-3/2}$. $\Delta
\eta$ and other observables exhibit log-time periodic oscillations which can be
interpreted as due to a growth mechanism where stretching and break-up of
domains cyclically occur.
  In the case of an oscillating shear a cross-over phenomenon is observed:
Initially the evolution is characterized by the same growth exponents as for a
stationary flow. For longer times the phase separating structure cannot align
with the oscillating drift and a different regime is entered with an isotropic
growth and the same exponents of the case without shear.

</DOC>
<DOC>
<DOCNO> 117375 </DOCNO>
Infrared Imaging of the Gravitational Lens PG 1115+080 with the Subaru


  We present high spatial resolution images of the gravitational-lens system PG
1115+080 taken with the near-infrared camera (CISCO) on the Subaru telescope.
The FWHM of the combined image is $0.''32$ in the $K'$-band,
yielding spatial resolution of $0.''14$ after a deconvolution
procedure. This is a first detection of an extended emission adjacent to the
A1/A2 components, indicating the presence of a fairly bright emission region
with a characteristic angular radius of $\sim$ 5 mas (40 pc). The near-infrared
image of the Einstein ring was extracted in both the $J$ and $K'$ bands. The
$J-K'$ color is found to be significantly redder than that of a synthetic model
galaxy with an age of 3 Gyr, the age of the universe at the quasar redshift.

</DOC>
<DOC>
<DOCNO> 11489 </DOCNO>
Nonlinear Quantum Transport and Current Noise


  We study nonequilibrium transport and noise in a generic dissipative
tight-binding model. Within a real-time path integral approach, we derive
formally exact series expressions in the number of tunneling events for the
noise valid for arbitrary bias, frequency and temperature. At zero temperature,
the low-frequency noise can be summed in analytic form. The resulting
Shiba-like $|\omega|$-singularity is a consequence of the $1/t^2$ decay law for
the current correlation function. At finite temperature, this singularity is
smoothed out.

</DOC>
<DOC>
<DOCNO> 170286 </DOCNO>
A Note on Quantum Key Channel Efficiency and Security using Correlated


  Quantum-correlated photon sources provide a means of suppressing multiple
photon emission and thus improving the security and efficiency of quasi
single-photon quantum key distribution systems. We present illustrative
photon-counting statistics for a Poissonian source conditioned by photon number
measurements on a fully correlated twin beam with a non-ideal photon counter.
We show that high photon counting efficiency is needed to obtain significant
improvement in channel efficiency (bits per symbol) and/or security (in the
form of reduced Shannon entropy leakage) over a single beam source.

</DOC>
<DOC>
<DOCNO> 102872 </DOCNO>
Foliated group actions and cyclic cohomology


  We prove a cyclic Lefschetz formula for foliations. To this end, we define a
notion of equivariant cyclic cohomology and show that its expected pairing with
K-theory is well defined. This enables to associate to any invariant transverse
current on a compact foliated manifold, a Lefschetz formula for leafwise
preserving isometries.

</DOC>
<DOC>
<DOCNO> 9255 </DOCNO>
Relaxation Properties of Small-World Networks


  Recently, Watts and Strogatz introduced the so-called small-world networks in
order to describe systems which combine simultaneously properties of regular
and of random lattices. In this work we study diffusion processes defined on
such structures by considering explicitly the probability for a random walker
to be present at the origin. The results are intermediate between the
corresponding ones for fractals and for Cayley trees.

</DOC>
<DOC>
<DOCNO> 69952 </DOCNO>
String Representation of Gauge Theories


  In this talk, various approaches to the problem of evaluation of the field
strength correlators in the SU(3)-gluodynamics, which play the major role in
the Stochastic Vacuum Model, are reviewed. This is done in the framework of the
effective Abelian-projected theories under the various assumptions implied on
the properties of the ensemble of Abelian-projected monopoles. In particular,
within the assumption on the condensation of the monopole Cooper pairs, the
main method of investigation is the string representation of field strength
correlators. The calculation of the bilocal field strength correlator in the 3D
effective theory, where Abelian-projected monopoles are assumed to form a gas,
based on the string representation for the Wilson loop in this theory, is also
presented.

</DOC>
<DOC>
<DOCNO> 70666 </DOCNO>
Analytical calculation of heavy baryon correlators in NLO of


  We present analytical next-to-leading order results for the correlator of
baryonic currents at the three-loop level with one finite mass quark. We obtain
the massless and the HQET limits of the correlator as particular cases from the
general formula, we also give explicit expressions for the moments of the
spectral density. Calculations have been performed with an extensive use of the
symbolic manipulation programs MATHEMATICA and REDUCE.

</DOC>
<DOC>
<DOCNO> 40564 </DOCNO>
Measurement of the B0 and B- meson lifetimes in ALEPH


  The lifetimed of the Bbar0 and B- meson lifetimes are measured using data
recorded on the Z peak with the ALEPH detector at LEP. An improved analysis
based on partially reconstructed Bbar0 -> D*+l-nubar and B- -> D0l-nubar decays
is presented.

</DOC>
<DOC>
<DOCNO> 9128 </DOCNO>
Role of Fermi-level pinning in nanotube Schottky diodes


  At semiconductor-metal junctions, the Schottky barrier height is generally
fixed by "Fermi-level pinning". We find that when a semiconducting carbon
nanotube is end-contacted to a metal (the optinal geometry for nanodevices),
the behavior is radically different. Even when the Fermi level is fully
"pinned" at the interface, the turn-on voltage is that expected for the
unpinned junction. Thus the threshold may be adjusted for optimal device
performance, which is not possible in planar contacts. Similar behavior is
expected at heterojunctions between nanotubes and semiconductors.

</DOC>
<DOC>
<DOCNO> 72236 </DOCNO>
Three generations on a local vortex in extra dimensions


  We develop an approach to the origin of three generations of the Standard
Model fermions from one generation in a higher-dimensional theory, where
four-dimensional fermions appear as zero modes trapped in the core of a
topological defect, and the hierarchy of masses and mixings is produced by wave
function overlaps in extra dimensions. We present a model with unbroken U(1)
symmetry where three zero modes appear on an Abrikosov-Nielsen-Olesen vortex
due to nontrivial scalar--fermion interactions.

</DOC>
<DOC>
<DOCNO> 117072 </DOCNO>
Binding Energies and Scattering Observables in the 4Helium3 Atomic


  The 4He3 system is investigated using a hard-core version of the Faddeev
differential equations and realistic 4He-4He interactions. We calculate the
binding energies of the 4He trimer but concentrate in particular on scattering
observables. The atom-diatom scattering lengths are calculated as well as the
atom-diatom phase shifts for center of mass energies up to 2.45 mK.

</DOC>
<DOC>
<DOCNO> 116280 </DOCNO>
The Galaxy Distribution: Homogeneous, Fractal, or Neither


  From the standpoint of theoretical physics we can treat Newtonian cosmology
as a problem in nonlinear dynamics. The attempt to average the density, in
search of a method of making contact between theory and observation, is
replaced by the more systematic idea of coarsegraining. I also explain in this
context why two previous attempts at the construction of hierarchical models of
the universe are not useful in data analysis. The main ideas behind two older
competing data analyses purporting to show evidence from galaxy statistics for
either a homogeneous and isotropic universe in one case, and for a mono-fractal
universe in the other, are presented and discussed. I also present the method
and results of a newer data analysis that shows that visible matter provides no
evidence that would allow us to claim that the cosmological principle holds, or
that the universe is fractal (or multifractal). In other words, observational
data provides us with no evidence that the universe is either homogeneous and
isotropic, or monofractal.

</DOC>
<DOC>
<DOCNO> 39657 </DOCNO>
Gamma(*)Gamma(*) reaction at high energies


  The energy available for gamma(*)gamma(*) physics at LEP2 is opening a new
window on the study of diffractive phenomena, both non-perturbative and
perturbative. We discuss some of the uncertainties and problems connected with
the experimental measurements and their interpretation.

</DOC>
<DOC>
<DOCNO> 102087 </DOCNO>
A momotonicity approach to nonlinear Dirichlet problems in perforated


  We study the asymptotic behaviour of solutions to Dirichlet problems in
perforated domains for nonlinear elliptic equations associated with monotone
operators. The main difference with respect to the previous papers on this
subject is that no uniformity is assumed in the monotonicity condition. Under a
very general hypothesis on the holes of the domains, we construct a limit
equation, which is satisfied by the weak limits of the solutions. The
additional term in the limit problem depends only on the local behaviour of the
holes, which can be expressed in terms of suitable nonlinear capacities
associated with the monotone operator.

</DOC>
<DOC>
<DOCNO> 9473 </DOCNO>
Electronic and Structural Properties of C$_{36}$ Molecule


  The extended SSH model and Bogoliubov-de Gennes(BdeG) formalism are applied
to investigate the electronic properties and stable lattice configurations of
C$_{36}$. We focus the problem on the molecule's unusual $D_{6h}$ symmetry. The
electronic part of the Hamiltonian without Coulomb interaction is solved
analytically. We find that the gap between HOMO and LUMO is small due to the
long distance hopping between the 2nd and 5th layers. The charge densities of
HOMO and LUMO are mainly distributed in the two layers, that causes a large
splitting between the spin triplet and singlet excitons. The differences of
bond lengths, angles and charge densities among the molecule and polarons are
discussed.

</DOC>
<DOC>
<DOCNO> 117009 </DOCNO>
Investigations of Amplitude and Phase Excitation Profiles in Femtosecond


  We present an effective linear response approach to pump-probe femtosecond
coherence spectroscopy in the well separated pulse limit. The treatment
presented here is based on a displaced and squeezed state representation for
the non-stationary states induced by an ultrashort pump laser pulse or a
chemical reaction. The subsequent response of the system to a delayed probe
pulse is modeled using closed form non-stationary linear response functions,
valid for a multimode vibronically coupled system at arbitrary temperature.
When pump-probe signals are simulated using the linear response functions, with
the mean nuclear positions and momenta obtained from a rigorous moment analysis
of the pump induced (doorway) state, the signals are found to be in excellent
agreement with the conventional third order response approach. The key
advantages offered by the moment analysis based linear response approach
include a clear physical interpretation of the amplitude and phase of
oscillatory pump-probe signals, a dramatic improvement in computation times, a
direct connection between pump-probe signals and equilibrium absorption and
dispersion lineshapes, and the ability to incorporate coherence such as those
created by rapid non-radiative surface crossing. We demonstrate these aspects
using numerical simulations, and also apply the present approach to the
interpretation of experimental amplitude and phase measurements on reactive and
non-reactive samples of the heme protein Myoglobin. The role played by
inhomogeneous broadening in the observed amplitude and phase profiles is
discussed in detail. We also investigate overtone signals in the context of
reaction driven coherent motion.

</DOC>
<DOC>
<DOCNO> 118772 </DOCNO>
On breaking the age-metallicity degeneracy in early-type galaxies:


  A simple model of chemical enrichment in cluster early-type galaxies is
presented where the main parameters driving the formation of the stellar
component are reduced to four: infall timescale (tf), formation epoch (zF),
star formation efficiency (Ceff) and fraction of gas ejected in outflows
(Bout). We find that only variations in Bout or Ceff can account for the
colour-magnitude relation, so that the most luminous galaxies had low values of
ejected gas and high efficiencies. The combination of chemical enrichment
tracks with population synthesis models is used to explore the correlation
between mass-to-light ratios and masses. A significant slope mismatch is found
between stellar and total M/L ratios, which cannot be explained by an age
spread and implies a non-linear correlation between total and stellar mass. The
sequences driven by star formation efficiency and outflows are shown to predict
different trends at high redshift. Measurement of the dependence of the tilt of
the fundamental plane on redshift will break the degeneracy between outflows
and star formation efficiency, which will enable us to determine whether the
colour-magnitude relation is controlled by age or metallicity.

</DOC>
<DOC>
<DOCNO> 69411 </DOCNO>
Constraining New Physics with Vertex Corrections


  We discuss how new physics not encompassed within the STU oblique correction
framework can be constrained from precision electroweak measurements via vertex
corrections to Z-pole observables.

</DOC>
<DOC>
<DOCNO> 10055 </DOCNO>
Dynamics of a Bunch of Carbon Nano-tubes


  Nano-diameter tubules made of folded graphitic sheets have drawn the
attention of physicists ever since the advent of fullerene research. These are
interesting because of their conductivity (depends upon chirality) as well as
their mechanical properties. Bunches of such tubes, single-walled and each of
same diameter (~14A), have been produced in the laboratory. In this work we
explore the mechanical properties of the bunch (hexagonal packing), having
assumed, for simplicity, uniform continuous distribution of carbon atoms on
each tube. The atom-atom potential (6-exp) is of Kitaigorodsky type where only
inter-tube interactions are considered. Intra-tube interactions are not
considered (implying a rigid tube model). This approximation works very well
for pure C60 solid. We find that the range of external modes is not well
separated from the radial mode frequency of the single tube as indicated by
measured data. Therefore interpretation of experimentally observed frequencies
needs to be done in terms of total modes of the bunch, including internal as
well as external modes. We have also studied pressure dependent deformations of
such a bunch which is found to be very interesting and is likely to provide
information about their mechanical strength.

</DOC>
<DOC>
<DOCNO> 119876 </DOCNO>
Large-Scale Structures behind the Southern Milky Way in the Great


  A deep optical galaxy search behind the southern Milky Way and a subsequent
redshift survey of the identified obscured galaxies traces clusters and
superclusters into the deepest layers of Galactic foreground extinction (A_B <=
3^m - 5^m). In the Great Attractor region, we have identified a low-mass
cluster (the Centaurus-Crux cluster) at (l, b, v, sigma) = (305.5deg, +5.5deg,
6214 km/s, 472 km/s) and found that ACO 3627 (the Norma cluster) at (l, b, v,
sigma) = (325.3deg, -7.2deg, 4844 km/s, 848 km/s) is the most massive cluster
in the Great Attractor region known to date. It is comparable in virial mass,
richness and size to the well-known but more distant Coma cluster. The Norma
cluster most likely marks the bottom of the potential well of the Great
Attractor. It is located at the intersection of two main large-scale
structures, the Centaurus Wall and the Norma supercluster. The flow field
observed around the Great Attractor probably is caused by the confluence of
these two massive structures.

</DOC>
<DOC>
<DOCNO> 152636 </DOCNO>
Heisenberg-type structures of one-dimensional quantum Hamiltonians


  We construct a Heisenberg-like algebra for the one dimensional infinite
square-well potential in quantum mechanics. The ladder operators are realized
in terms of physical operators of the system as in the harmonic oscillator
algebra. These physical operators are obtained with the help of variables used
in a recently developed non commutative differential calculus. This
\textquotedblleft square-well algebra\textquotedblright is an example of an
algebra in a large class of generalized Heisenberg algebras recently
constructed. This class of algebras also contains $q$-oscillators as a
particular case. We also discuss the physical content of this large class of
algebras.

</DOC>
<DOC>
<DOCNO> 12740 </DOCNO>
One-loop approximation for the Heisenberg antiferromagnet


  We use the diagram technique for spin operators to calculate Green's
functions and observables of the spin-1/2 quantum Heisenberg antiferromagnet on
a square lattice. The first corrections to the self-energy and interaction are
taken into account in the chain diagrams. The approximation reproduces main
results of Takahashi's modified spin-wave theory [Phys. Rev. B 40, 2494 (1989)]
and is applicable in a wider temperature range. The energy per spin calculated
in this approximation is in good agreement with the Monte Carlo and
small-cluster exact-diagonalization calculations in the range 0 <= T < 1.2J
where J is the exchange constant. For the static uniform susceptibility the
agreement is good for T < 0.6J and becomes somewhat worse for higher
temperatures. Nevertheless the approximation is able to reproduce the maximum
in the temperature dependence of the susceptibility near T = 0.9J.

</DOC>
<DOC>
<DOCNO> 10904 </DOCNO>
New quantum phase transitions in the two-dimensional J1-J2 model


  We analyze the phase diagram of the frustrated Heisenberg antiferromagnet,
the J1-J2 model, in two dimensions. Two quantum phase transitions in the model
are already known: the second order transition from the Neel state to the spin
liquid state at (J_2/J_1)_{c2}=0.38, and the first order transition from the
spin liquid state to the collinear state at (J_2/J_1)_{c4}=0.60. We have found
evidence for two new second order phase transitions: the transition from the
spin columnar dimerized state to the state with plaquette type modulation at
(J_2/J_1)_{c3}=0.50(2), and the transition from the simple Neel state to the
Neel state with spin columnar dimerization at (J_2/J_1)_{c1}=0.34(4). We also
present an independent calculation of (J_2/J_1)_{c2}=0.38 using a new approach.

</DOC>
<DOC>
<DOCNO> 116407 </DOCNO>
RF-induced evaporative cooling and BEC in a high magnetic field


  We present the design of our iron-core electromagnet for BEC, and how to
solve the specific experimental problems raised by this technique. After
presenting the experimental set-up, we address the interruption of runaway
evaporative cooling when the Zeeman effect is not linear. We present the ways
to circumvent this problem, use of multiple RF frequencies, sympathetic cooling
and show some applications of these high magnetic fields (cavity coupling, high
confinement).

</DOC>
<DOC>
<DOCNO> 9063 </DOCNO>
Influence of auto-organization and fluctuation effects on the kinetics


  We study analytically kinetics of an elementary bimolecular reaction scheme
of the Langmuir-Hinshelwood type taking place on a d-dimensional catalytic
substrate. We propose a general approach which takes into account explicitly
the influence of spatial correlations on the time evolution of particles mean
densities and allows for the analytical analysis. In terms of this approach we
recover some of known results concerning the time evolution of particles mean
densities and establish several new ones.

</DOC>
<DOC>
<DOCNO> 71000 </DOCNO>
The non-perturbative QCD potential


  The potential between heavy quarks can be rigorously defined in a QCD
effective field theories framework. I discuss the general situation when the
coupling constant may not be considered small and provide an explicit
expression for the potential valid up to order 1/m^2. Spin dependent and spin
independent terms are expressed in terms of Wilson loops, completing an ideal
journey started twenty years ago with the classical work of Eichten and
Feinberg.

</DOC>
<DOC>
<DOCNO> 101411 </DOCNO>
Homology of complete symbols and non-commutative geometry


  We identify the periodic cyclic homology of the algebra of complete symbols
on a differential groupoid $\GR$ in terms of the cohomology of $S^*(\GR)$, the
cosphere bundle of $A(\GR)$, where $A(\GR)$ is the Lie algebroid of $\GR$. We
also relate the Hochschild homology of this algebra with the homogeneous
Poisson homology of the space $A^*(\GR) \smallsetminus 0 \cong S^*(\GR) \times
(0,\infty)$, the dual of $A(\GR)$ with the zero section removed. We use then
these results to compute the Hochschild and cyclic homologies of the algebras
of complete symbols associated with manifolds with corners, when the
corresponding Lie algebroid is rationally isomorphic to the tangent bundle.

</DOC>
<DOC>
<DOCNO> 118137 </DOCNO>
Relativistic Effects in the Pulse Profile of the 2.5 msec X-Ray Pulsar


  We analyze the properties of the pulsed emission from the accreting
millisecond pulsar SAX J1808.4-3658 in observations of its April 1998 outburst
by the Rossi X-Ray Timing Explorer. Pulse phase spectroscopy shows that the
emission evolves from a hard spectrum (power law with photon index 2.39+-0.06)
to a soft spectrum (index 3.39+-0.24). This softening is also observable as a
phase lag in the fundamental of low-energy photons with respect to high-energy
photons. We show that this lag is roughly constant over ten days of the
outburst. We fit these data with a model where the pulse emission is from a hot
spot on the rotating neutron star and the flux as a function of phase is
calculated including the effects of general relativity. The energy-dependent
lags are very well described by this model. The harder spectra at earlier
phases (as the spot approaches) are the result of larger Doppler boosting
factors which are important for this fast pulsar.

</DOC>
<DOC>
<DOCNO> 40339 </DOCNO>
A Light Bottom Squark in the MSSM


  We study the compatibility of a light bottom squark M_{\tilde b}< O(10 GeV)
in the unconstrained MSSM. We consider the one-loop radiative corrections which
are large for a heavy gluino (> O(150 GeV)). We then consider the
renormalization group flow up to the Grand Unified scale. For most regions of
the parameter space with a light sbottom we find colour and charge breaking
minima. Only a small window in gluino mass and tan(beta) is consistent with all
bounds. This is alleviated by a light gluino, which is however only marginally
experimentally allowed.

</DOC>
<DOC>
<DOCNO> 99342 </DOCNO>
Triangular de Rham Cohomology of Compact Kahler Manifolds


  We study the de Rham 1-cohomology H^1_{DR}(M,G) of a smooth manifold M with
values in a Lie group G. By definition, this is the quotient of the set of flat
connections in the trivial principle bundle $M\times G$ by the so-called gauge
equivalence. We consider the case when M is a compact K\"ahler manifold and G
is a solvable complex linear algebraic group of a special class which contains
the Borel subgroups of all complex classical groups and, in particular, the
group $T_n(\Bbb C)$ of all triangular matrices. In this case, we get a
description of the set H^1_{DR}(M,G) in terms of the 1-cohomology of M with
values in the (abelian) sheaves of flat sections of certain flat Lie algebra
bundles with fibre $\frak g$ (the Lie algebra of G) or, equivalently, in terms
of the harmonic forms on M representing this cohomology.

</DOC>
<DOC>
<DOCNO> 13693 </DOCNO>
Algorithm for molecular dynamics simulations of spin liquids


  A new symplectic time-reversible algorithm for numerical integration of the
equations of motion in magnetic liquids is proposed. It is tested and applied
to molecular dynamics simulations of a Heisenberg spin fluid. We show that the
algorithm exactly conserves spin lengths and can be used with much larger time
steps than those inherent in standard predictor-corrector schemes. The results
obtained for time correlation functions demonstrate the evident dynamic
interplay between the liquid and magnetic subsystems.

</DOC>
<DOC>
<DOCNO> 100083 </DOCNO>
Holomorphic Jet Bundles


  Chern number formulas for holomorphic jet bundles are computed for projective
curves and for projective surfaces. These formulas are used to show that
certain minimal surfaces of general type (generic hypersurfaces of degree at
least 5 in projective 3-spaces in particular) are hyperbolic in the sense of
complex hyperbolic geometry.

</DOC>
<DOC>
<DOCNO> 120730 </DOCNO>
Dynamics of Stars and Globular Clusters in M87


  We examine the dynamics of the stars and globular clusters in the nearby
giant galaxy M87 and constrain the mass distribution, using all the available
data over a large range of radii, including higher-order moments of the stellar
line-of-sight velocity distributions and the discrete velocities of over two
hundred globular clusters. We introduce an extension of spherical orbit
modeling methods that makes full use of all the information in the data, and
provides very robust constraints on the mass models. We conclusively rule out a
constant mass-to-light ratio model, and infer that the radial density profile
of the galaxy's dark halo falls off more slowly than 1/r^2, suggesting that the
potential of the Virgo Cluster is already dominant at r ~ 300" ~ 20 kpc.

</DOC>
<DOC>
<DOCNO> 70983 </DOCNO>
Problems with empirical bounds for strangelet production at RHIC


  Recent papers by Busza et al. and Dar et al. have considered empirical bounds
on the risk of producing a hypothetical stable negatively charged strangelet at
the Brookhaven relativistic heavy ion collider (RHIC) experiments, and thereby
destroying the Earth. We examine here ways in which these bounds could,
hypothetically, be evaded. We find several,some of which have not previously
been considered. These possible flaws do not affect the theoretical arguments
against the existence of negatively charged strangelets or the possibility of
producing them at RHIC if they were to exist.

</DOC>
<DOC>
<DOCNO> 9165 </DOCNO>
Crowd-anticrowd model of the Minority Game


  We provide a theoretical description of the Minority Game in terms of crowd
effects. The size of the fluctuations arising in the game is controlled by the
interplay between crowds of like-minded agents and their anti-correlated
partners (anticrowds). The theoretical results are in good agreement with the
numerical simulations over the entire parameter range of interest.

</DOC>
<DOC>
<DOCNO> 170116 </DOCNO>
Unconditional Pointer States from Conditional Master Equations


  When part of the environment responsible for decoherence is used to extract
information about the decohering system, the preferred {\it pointer states}
remain unchanged. This conclusion -- reached for a specific class of models --
is investigated in a general setting of conditional master equations using
suitable generalizations of predictability sieve. We also find indications that
the einselected states are easiest to infer from the measurements carried out
on the environment.

</DOC>
<DOC>
<DOCNO> 70794 </DOCNO>
Sigma-term physics in the perturbative chiral quark model


  We apply the perturbative chiral quark model (PCQM) at one loop to analyse
meson-baryon sigma-terms. Analytic expressions for these quantities are
obtained in terms of fundamental parameters of low-energy pion-nucleon physics
(weak pion decay constant, axial nucleon coupling, strong pion-nucleon form
factor) and of only one model parameter (radius of the nucleonic three-quark
core). Our result for the piN sigma term of about 45 MeV is in good agreement
with the value deduced by Gasser, Leutwyler and Sainio using
dispersion-relation techniques and exploiting the chiral symmetry constraints.

</DOC>
<DOC>
<DOCNO> 100237 </DOCNO>
A mean identity for longest increasing subsequence problems


  We show that a wide variety of generalized increasing subsequence problems
admit a one parameter family of extensions for which we can exactly compute the
mean length of the longest increasing subsequence. By the nature of the
extension, this gives upper bounds on the mean in the unextended model, which
turn out to be asymptotically tight for all of the models that have so far been
analyzed. A heuristic analysis based on this fact gives not just the asymptotic
mean but also the asymptotic scale factor, again agreeing with all known cases.

</DOC>
<DOC>
<DOCNO> 117808 </DOCNO>
A GPS-based method to model the plasma effects in VLBI observations


  Global Positioning System (GPS) satellites broadcast at frequencies of
1,575.42 MHz (L1) and of 1,227.60 MHz (L2). The dispersive property of the
ionosphere can be used to combine independent measurements at the two
frequencies to estimate the total electron content (TEC) between a GPS receiver
site and a broadcasting satellite. Such measurements, made at sites near to
Very Long Baseline Interferometry (VLBI) sites, can be used to estimate the
ionospheric contribution to VLBI observables. For our 1991.9 astrometric VLBI
experiment in which we obtained group-delay observations in the 8.4 and 2.3 GHz
bands simultaneously, we found that the GPS and VLBI determinations of the
ionosphere delays agreed with root-mean-square differences below 0.15 ns for
intercontinental baselines and 0.10 ns for continental ones. We also
successfully applied the GPS-based procedure to reduce the ionospheric effect
in phase delays used for high precision differenced astrometry at 8.4 GHz for
this same experiment.

</DOC>
<DOC>
<DOCNO> 85570 </DOCNO>
Quantum-mechanical model of the Kerr-Newman black hole


  We consider a Hamiltonian quantum theory of stationary spacetimes containing
a Kerr-Newman black hole. The physical phase space of such spacetimes is just
six-dimensional, and it is spanned by the mass $M$, the electric charge $Q$ and
angular momentum $J$ of the hole, together with the corresponding canonical
momenta. In this six-dimensional phase space we perform a canonical
transformation such that the resulting configuration variables describe the
dynamical properties of Kerr-Newman black holes in a natural manner. The
classical Hamiltonian written in terms of these variables and their conjugate
momenta is replaced by the corresponding self-adjoint Hamiltonian operator and
an eigenvalue equation for the Arnowitt-Deser-Misner (ADM) mass of the hole,
from the point of view of a distant observer at rest, is obtained. In a certain
very restricted sense, this eigenvalue equation may be viewed as a sort of
"Schr\"odinger equation of black holes". Our "Schr\"odinger equation" implies
that the ADM mass, electric charge and angular momentum spectra of black holes
are discrete, and the mass spectrum is bounded from below. Moreover, the
spectrum of the quantity $M^2-Q^2-a^2$, where $a$ is the angular momentum per
unit mass of the hole, is strictly positive when an appropriate self-adjoint
extension is chosen. The WKB analysis yields the result that the large
eigenvalues of $M$, $Q$ and $a$ are of the form $\sqrt{2n}$, where $n$ is an
integer. It turns out that this result is closely related to Bekenstein's
proposal on the discrete horizon area spectrum of black holes.

</DOC>
<DOC>
<DOCNO> 174521 </DOCNO>
Results from SKM-200-GIBS on multiparticle azimuthal correlations in


  The transverse momentum technique is used to analyse charged-particle
exclusive data in central C-Ne and C-Cu interactions at energy of 3.7 GeV per
nucleon. Clear evidence of in-plane and out-of-plane (squeeze-out) flow effects
for protons and pi^{-} mesons have been obtained. In C-Ne interactions in-plane
flow of pi^{-} mesons is in the same direction as for the protons, while in
C-Cu collisions pions show antuflow behaviour. From the transverse momentum and
azimuthal distributions of protons and pi^{-} mesons with respect to the
reaction plane, the flow (the measure of the amount of collective transverse
momentum transfer in the reaction plane) and the parameter a_{2} (the measure
of the anisotropic emission strength) have been extracted. The flow effects
increase with the mass of the particle and the mass number of target A_{T}. The
comparison of our in-plane flow results with flow data for various
projectile/target configurations was made using the scaled flow F_{S}=F/(A_{P}
^{1/3}+A_{T}^{1/3}). F_{S} demonstrates a common scaling behaviour for flow
values from different systems. The Quark Gluon String Model (QGSM) was used for
the comparison with the experimental data. The QGSM yields a signature of
in-plane and out-of-plane flow effects in C-ne and C-Cu collisions for protons.

</DOC>
<DOC>
<DOCNO> 71898 </DOCNO>
An Estimate of the K0-K0bar Mixing Amplitude


  We computed the B_K parameter on the lattice by using a non-perturbatively
improved Wilson action. From our quenched simulation, in the MSbar scheme and
at mu=2 GeV, we obtain B_K=0.73(7)^{+0.05}_{-0.01}. To gain some insight in the
systematic errors due to the use of the quenched approximation, we also made
the unquenched computation with Wilson fermions. We do not observe any
significant deviation with respect to the quenched result.

</DOC>
<DOC>
<DOCNO> 116495 </DOCNO>
Lagrangians and Hamiltonians for High School Students


  A discussion of Lagrangian and Hamiltonian dynamics is presented at a level
which should be suitable for advanced high school students. This is intended
for those who wish to explore a version of mechanics beyond the usual Newtonian
treatment in high schools, but yet who do not have advanced mathematical
skills.

</DOC>
<DOC>
<DOCNO> 69746 </DOCNO>
Leptoquark Searches at Future Colliders


  Leptoquark searches are considered for future experiments at HERA, Tevatron,
LHC, TESLA and THERA. Expected exclusion limits from direct leptoquark searches
(leptoquark pair production and single leptoquark production) are compared with
indirect limits expected from the contact interaction analysis. Strongest
limits on the leptoquark masses and couplings are expected from high luminosity
LHC data. If the leptoquark signal suggested by the existing data is detected
at LHC, with mass below 1 TeV, TESLA will be an ideal place to study leptoquark
properties, provided that the leptoquark Yukawa coupling is not too small.

</DOC>
<DOC>
<DOCNO> 178600 </DOCNO>
Clocking hadronization in relativistic heavy ion collisions with balance


  A novel state of matter has been hypothesized to exist during the early stage
of relativistic heavy ion collisions, with normal hadrons not appearing until
several fm/c after the start of the reaction. To test this hypothesis,
correlations between charges and their associated anticharges are evaluated
with the use of balance functions. It is shown that late-stage hadronization is
characterized by tightly correlated charge/anticharge pairs when measured as a
function of relative rapidity.

</DOC>
<DOC>
<DOCNO> 70527 </DOCNO>
The Anomaly and Reggeon Field Theory in QCD


  The appearance of the U(1) anomaly in the interactions of reggeized gluons is
described. Also discussed is the crucial role the anomaly can play in providing
the non-perturbative properties necessary for a transition from gluon and quark
reggeon diagrams to hadron reggeons and a reggeon field theory description of
the pomeron.

</DOC>
<DOC>
<DOCNO> 68364 </DOCNO>
Resonant sneutrino production in Supersymmetry with R-parity violation


  The resonant production of sneutrinos at the LHC via the R-parity violating
couplings $\l '_{ijk} L_i Q_j D^c_k$ is studied through its three-leptons
signature. A detailed particle level study of signal and background is
performed using a fast simulation of the ATLAS detector. Through the full
reconstruction of the cascade decay, a model-independent and precise
measurement of the masses of the involved sparticles can be performed. Besides,
this signature can be detected for a broad class of supersymmetric models, and
for a wide range of values of several $\l '_{ijk}$ coupling constants. Within
the MSSM, the production of a 900 GeV sneutrino for
$\lambda^{\prime}_{211}>0.05$, and of a 350 GeV sneutrino for
$\lambda^{\prime}_{211}>0.01$ can be observed within the first three years of
LHC running.

</DOC>
<DOC>
<DOCNO> 80841 </DOCNO>
Vortices versus monopoles in color confinement


  We construct the creation operator of a vortex for SU(2) pure gauge theory
using the methods developed for monopoles. We interpret its vacuum expectation
value as a disorder parameter for the deconfinement phase transition and find
that it behaves in the vacuum in a similar way to monopoles. Results are
extrapolated to the thermodynamical limit using finite-size scaling.

</DOC>
<DOC>
<DOCNO> 170306 </DOCNO>
Dynamics, Thermodynamics, and Time-Asymmetry


  064<p type="texpara" tag="Body Text" et="abstract" bin="clone" >There are two
schools, or lines of thought, that try to unify the apparently divergent laws
of dynamics and thermodynamics and to explain the observed time-asymmetry of
the universe, and most of its sub-systems, in spite of the fact that these
systems are driven by time-symmetric evolution equations. They will be called
the coarse-graining and the fine-graining schools (even if these names describe
only a part of their philosophy). Coarse-graining school obtains time-asymmetry
via a projection of the state space on a space of ''relevant'' states. The
corresponding projection of the primitive reversible evolution laws yields
effective irreversible evolution laws for the relevant states. Fine-graining
always use the same primitive reversible evolution laws. But these laws (in
adequate extensions of the usual spaces where these laws are formulated) have a
set of solutions $S$ that can be decompose in two subsets $S_{+\text{}}$ and
$S_{-}$ of time asymmetric solutions. Choosing one of these two sets, as the
arena to formulate the theory, time asymmetry is established. The aim of these
lectures is to explain, in the simplest- self-contained, unbiased, and, honest
way, the main characteristics of both schools and to point out the advantages
and disadvantages of both formalism, in such a way that, the polemic between
the schools, turns out to be explicit and organized in the mind of the reader
(who will be considered the supreme judge to give the final verdict).
  064<p type="texpara" tag="Body Text" et="abstract" bin="clone" >Some
cosmological features of the theory will be also considered, mainly the problem
of the low entropy initial state of the universe

</DOC>
<DOC>
<DOCNO> 151865 </DOCNO>
External Fields as Intrinsic Geometry


  There is an interesting dichotomy between a space-time metric considered as
external field in a flat background and the same considered as an intrinsic
part of the geometry of space-time. We shall describe and compare two other
external fields which can be absorbed into an appropriate redefinition of the
geometry, this time a noncommutative one. We shall also recall some previous
incidences of the same phenomena involving bosonic field theories. It is known
that some such theories on the commutative geometry of space-time can be
re-expressed as abelian-gauge theory in an appropriate noncommutative geometry.
The noncommutative structure can be considered as containing extra modes all of
whose dynamics are given by the one abelian action.

</DOC>
<DOC>
<DOCNO> 40124 </DOCNO>
Determination of Scanning Efficiencies in Experiments Using Nuclear


  During their exposure, nuclear emulsion sheets detect both tracks from
experiment-related particles, as well as a considerable amount of background
tracks, mainly due to cosmic rays. Unless the exposure has been fairly short,
it is therefore fairly likely that a fraction of the tracks that have been
identified as belonging to the particles the experiment is interested in, are
really due to background. A method, which allows to measure this fraction
reliably directly from the data, is described.

</DOC>
<DOC>
<DOCNO> 71963 </DOCNO>
Power counting and effective field theory for charmonium


  We hypothesize that the correct power counting for charmonia is in the
parameter Lambda_QCD/m_c, but is not based purely on dimensional analysis (as
is HQET). This power counting leads to predictions which differ from those
resulting from the usual velocity power counting rules of NRQCD. In particular,
we show that while Lambda_QCD/m_c power counting preserves the empirically
verified predictions of spin symmetry in decays, it also leads to new
predictions which include: A hierarchy between spin singlet and triplet octet
matrix elements in the J/psi system. A quenching of the net polarization in
production at large transverse momentum. No end point enhancement in radiative
decays. We discuss explicit tests which can differentiate between the
traditional and new theories of NRQCD.

</DOC>
<DOC>
<DOCNO> 40220 </DOCNO>
Experimental evidence for G.U.T. Proton Decay


  Deep underground in Kolar Gold Fields, in southern India, an experiment to
detect proton decay had been carried out since the end of 1980. Analysis of
data yielded the following results; (l) the life time of proton is about 1 x
1031 years, (2) it decays into wide spectrum of decay modes, p -> e+ + pai0, p
->anti-nutrino + K+ and so on, and (3) the life time and the distribution of
decay modes are close to the predictions of SU(5) SUSY GUT. Four events
representing possibly neutron oscillation are also seen.

</DOC>
<DOC>
<DOCNO> 7789 </DOCNO>
Universal and non-universal features of glassy relaxation in propylene


  It is demonstrated that the susceptibility spectra of supercooled propylene
carbonate as measured by depolarized-light-scattering, dielectric-loss, and
incoherent quasi-elastic neutron-scattering spectroscopy within the GHz window
are simultaneously described by the solutions of a two-component schematic
model of the mode-coupling theory (MCT) for the evolution of glassy dynamics.
It is shown that the universal beta-relaxation-scaling laws, dealing with the
asymptotic behavior of the MCT solutions, describe the qualitative features of
the calculated spectra. But the non-universal corrections to the scaling laws
render it impossible to achieve a complete quantitative description using only
the leading-order-asymptotic results.

</DOC>
<DOC>
<DOCNO> 70525 </DOCNO>
The Dirac Operator Spectrum and Effective Field Theory


  When chiral symmetry is spontaneously broken, the low-energy part of the
Dirac operator spectrum can be computed analytically in the chiral limit. The
tool is effective field theory or, equivalently in this case, Random Matrix
Theory.

</DOC>
<DOC>
<DOCNO> 101023 </DOCNO>
Submanifolds of symplectic manifolds with contact border


  We construct symplectic submanifolds of symplectic manifolds with contact
border. The boundary of such submanifolds is shown to be a contact submanifold
of the contact border. We also give a topological characterization of the
constructed submanifolds by means of a ``relative Lefschetz hyperplane
Theorem''. We sketch some of the applications of the results.

</DOC>
<DOC>
<DOCNO> 118055 </DOCNO>
Fluid Dark Matter


  Dark matter modeled as a classical scalar field that interacts only with
gravity and with itself by a potential that is close to quartic at large field
values and approaches a quadratic form when the field is small would be
gravitationally produced by inflation and at the present epoch could act like
an ideal fluid with pressure that is a function only of the mass density. This
could have observationally interesting effects on the core radii and solid body
rotation of dark matter halos and on the low mass end of the primeval mass
fluctuation power spectrum.

</DOC>
<DOC>
<DOCNO> 99518 </DOCNO>
Bloch's Conjecture and Chow Motives


  Let X be a complex surface with no nontrivial 2-forms. Then we show that
Bloch's conjecture is true (i.e. the Albanese map in this case is injective) if
and only if any homologically trivial idempotent in the ring of correspondences
vanishes. Furthermore the cube of the ideal of homologically trivial
correspondences is zero if these equivalent conditions are satisfied (e.g. if X
is not of general type).

</DOC>
<DOC>
<DOCNO> 11413 </DOCNO>
Long Range Proximity Effect in Hybrid Ferromagnetic/Superconducting


  We find that the dependence on temperature and magnetic field of the
electrical resistance of diffusive ferromagnetic nano-wires measured with
superconducting electrodes changes drastically with the distance, $L$, between
the ferromagnet/superconductor contacts, however is remarkably similar for the
wires with the same $L$ ranging from 300 nm to 1000 nm, prepared under
identical conditions. The result gives an evidence for the long-range
superconductor-induced changes in transport properties of ferromagnetic
nano-wires.

</DOC>
<DOC>
<DOCNO> 81020 </DOCNO>
Phase Structure of the 5D Abelian Higgs Model with Anisotropic Couplings


  We establish the phase diagram of the five-dimensional anisotropic Abelian
Higgs model by mean field techniques and Monte Carlo simulations. The
anisotropy is encoded in the gauge couplings as well as in the Higgs couplings.
In addition to the usual bulk phases (confining, Coulomb and Higgs) we find
four-dimensional ``layered'' phases (3-branes) at weak gauge coupling, where
the layers may be in either the Coulomb or the Higgs phase, while the
transverse directions are confining.

</DOC>
<DOC>
<DOCNO> 122000 </DOCNO>
The radio luminosity function from the low-frequency 3CRR, 6CE & 7CRS


  We measure the radio luminosity function (RLF) of steep-spectrum radio
sources using three redshift surveys of flux-limited samples selected at low
(151 & 178 MHz) radio frequency, low-frequency source counts and the local RLF.
The redshift surveys used are the new 7C Redshift Survey (7CRS) and the
brighter 3CRR and 6CE surveys totalling 356 sources with virtually complete
redshift information. This yields unprecedented coverage of the radio
luminosity versus z plane for steep-spectrum sources, and hence the most
accurate measurements of the steep-spectrum RLF yet made. We find that a simple
dual-population model for the RLF fits the data well, requiring differential
density evolution (with z) for the two populations. The low-luminosity
population can be associated with radio galaxies with weak emission lines, and
includes sources with both FRI and FRII radio structures; its comoving space
density $\rho$ rises by about one dex between z~0 and z~1 but cannot yet be
meaningfully constrained at higher redshifts. The high-luminosity population
can be associated with FRII radio galaxies and quasars with strong emission
lines; its $\rho$ rises by nearly three dex between z~0 and z~2. These results
mirror the situation seen in X-ray and optically-selected AGN. The integrated
radio luminosity density of the combination of the two populations is
controlled by the value of $\rho$ at the low-luminosity end of the RLF of the
high-luminosity population, a quantity which has been directly measured at z~1
by the 7CRS. We argue that robust determination of this quantity at higher
redshifts requires a new redshift survey based on a large (~1000 source) sample
about five times fainter than the 7CRS.

</DOC>
<DOC>
<DOCNO> 11982 </DOCNO>
Screening of Hydrodynamic Interactions in Semidilute Polymer Solutions:


  We study single-chain motion in semidilute solutions of polymers of length N
= 1000 with excluded-volume and hydrodynamic interactions by a novel algorithm.
The crossover length of the transition from Zimm (short lengths and times) to
Rouse dynamics (larger scales) is proportional to the static screening length.
The crossover time is the corresponding Zimm time. Our data indicate Zimm
behavior at large lengths but short times. There is no hydrodynamic screening
until the chains feel constraints, after which they resist the flow:
"Incomplete screening" occurs in the time domain.

</DOC>
<DOC>
<DOCNO> 84176 </DOCNO>
Supersymmetry of Black Strings in D=5 Gauged Supergravities


  Supersymmetry of five dimensional string solutions is examined in the context
of gauged D=5, N=2 supergravity coupled to abelian vector multiplets. We find
magnetic black strings preserving one quarter of supersymmetry and approaching
the half-supersymmetric product space AdS_3\times H^2 near the event horizon.
The solutions thus exhibit the phenomenon of supersymmetry enhancement near the
horizon, like in the cases of ungauged supergravity theories, where the near
horizon limit is fully supersymmetric. Finally, product space compactifications
are studied in detail, and it is shown that only for negative curvature
(hyperbolic) internal spaces, some amount of supersymmetry can be preserved.
Among other solutions, we find that the extremal rotating BTZ black hole
tensored by H^2 preserves one quarter of supersymmetry.

</DOC>
<DOC>
<DOCNO> 80941 </DOCNO>
Exact results and approximation schemes for the Schwinger model with the


  We propose new techniques to implement numerically the overlap-Dirac operator
which exploit the physical properties of the underlying theory to avoid nested
algorithms. We test these procedures in the two-dimensional Schwinger model and
the results are very promising. We also present a detailed computation of the
spectrum and chiral properties of the Schwinger Model in the overlap lattice
formulation.

</DOC>
<DOC>
<DOCNO> 119602 </DOCNO>
Evidence for a two-armed spiral in the Milky Way


  Emission profiles of the Galactic plane in K and at $240\micron$ are
presented, and features associated with the tangents of the spiral arms are
identified. In the K band, which traces stellar emission and suffers little
from absorbtion, features associated with the arm tangents indicate that a
two-armed logarithmic spiral dominates the nonaxisymmetric structure of the
Milky Way. In contrast, the $240\micron$ emission from dust entrained in the
interstellar gas is consistent with a four-armed model, in concordance with
radio data and optical spiral tracers. This suggests that the non-axisymmetric
mass perturbation responsible for the four-armed spiral structure in the gas
has a two rather than four-armed structure.

</DOC>
<DOC>
<DOCNO> 72100 </DOCNO>
Higgs production in gluon fusion to order \alpha_s^4


  The calculation of the NNLO QCD corrections to the partonic process gg -> H
is outlined. For the coupling of the Higgs boson to the gluons we use an
effective Lagrangian in the limit of a heavy top quark. The focus is on the
evaluation of the virtual two-loop corrections. It is shown that the leading
pole terms are in agreement with the general formula by Catani.

</DOC>
<DOC>
<DOCNO> 116669 </DOCNO>
On the role of mass growth in dusty plasma kinetics


  It is shown that absorption of ions by the dust grain may reduce the
effective translational temperature of the dust component below the ambient gas
temperature.

</DOC>
<DOC>
<DOCNO> 70558 </DOCNO>
Ultra High Energy Cosmic Rays and Gamma Ray Bursts from Axion Stars


  We propose a model in which ultra high energy cosmic rays and gamma ray
bursts are produced by collisions between neutron stars and axion stars. The
acceleration of such a cosmic ray is made by the electric field, $\sim 10^{15}
(B/10^{12} {G}) {eV} {cm}^{-1}$, which is induced in an axion star by
relatively strong magnetic field $B>10^{12}$ G of a neutron star. On the other
hand, similar collisions generate gamma ray bursts when magnetic field is
relatively small, e.g. $\leq 10^{10}$ G. Assuming that the axion mass is $\sim
10^{-9}$ eV, we can explain huge energies of the gamma ray bursts $\sim
10^{54}$ erg as well as the ultra high energies of the cosmic rays $\sim
10^{20}$ eV. We estimate rate of energy release in the collisions and we find
that the rate roughly agrees with observations. In addition, we show that these
axion stars are plausible candidates for MACHOs. Since the axion star induces
oscillating electric current under the magnetic field, observable monochromatic
radiations are emitted.

</DOC>
<DOC>
<DOCNO> 117862 </DOCNO>
Formation of Millisecond Pulsars with Heavy White Dwarf Companions -


  We have performed detailed numerical calculations of the non-conservative
evolution of close X-ray binary systems with intermediate-mass (2.0-6.0 M_sun)
donor stars and a 1.3 M_sun accreting neutron star. We calculated the thermal
response of the donor star to mass loss, in order to determine its stability
and follow the evolution of the mass transfer. Under the assumption of the
"isotropic re-emission model" we demonstrate that in many cases it is possible
for the binary to prevent a spiral-in and survive a highly super-Eddington
mass-transfer phase (1 << M_dot/M_Edd < 10^5) on a sub-thermal timescale, if
the convective envelope of the donor star is not too deep. These systems thus
provide a new formation channel for binary millisecond pulsars with heavy CO
white dwarfs and relatively short orbital periods (3-50 days). However, we
conclude that to produce a binary pulsar with a O-Ne-Mg white dwarf or P_orb ~1
day (e.g. PSR B0655+64) the above scenario does not work, and a spiral-in phase
is still considered the most plausible scenario for the formation of such a
system.

</DOC>
<DOC>
<DOCNO> 152147 </DOCNO>
Generalized *-Products, Wilson Lines and the Solution of the


  Higher order terms in the effective action of noncommutative gauge theories
exhibit generalizations of the *-product (e.g. *' and *-3). These terms do not
manifestly respect the noncommutative gauge invariance of the tree level
action. In U(1) gauge theories, we note that these generalized *-products occur
in the expansion of some quantities that are invariant under noncommutative
gauge transformations, but contain an infinite number of powers of the
noncommutative gauge field. One example is an open Wilson line. Another is the
expression for a commutative field strength tensor in terms of the
noncommutative gauge field. Seiberg and Witten derived differential equations
that relate commutative and noncommutative gauge transformations, gauge fields
and field strengths. In the U(1) case we solve these equations neglecting terms
of fourth order in the gauge field but keeping all orders in the noncommutative
parameter.

</DOC>
<DOC>
<DOCNO> 169832 </DOCNO>
Coherent States of Non-Linear Algebras:Application to Quantum Optics


  We present a general unified approach for finding the coherent states of
polynomially deformed algebras such as the quadratic and Higgs algebras, which
are relevant for various multiphoton processes in quantum optics. We give a
general procedure to map these deformed algebras to appropriate Lie algebras.
This is used, for the non compact cases, to obtain the annihilation operator
coherent states, by finding the canonical conjugates of these operators.
  Generalized coherent states, in the Perelomov sense also follow from this
construction. This allows us to explicitly construct coherent states associated
with various quantum optical systems.

</DOC>
<DOC>
<DOCNO> 8911 </DOCNO>
Electromagnetic Response of a $k_x\pm ik_y$ Superconductor: Effect of


  Effects of order parameter collective modes on electromagnetic response are
studied for a clean spin-triplet superconductor with $k_x\pm ik_y$ orbital
symmetry, which has been proposed as a candidate pairing symmetry for
Sr$_2$RuO$_4$. It is shown that the $k_x \pm ik_y$ superconductor has
characteristic massive collective modes analogous to the clapping mode in the
A-phase of superfluid $^3$He. We discuss the contribution from the collective
modes to ultrasound attenuation and electromagnetic absorption. We show that in
the electromagnetic absorption spectrum the clapping mode gives rise to a
resonance peak well below the pair breaking frequency, while the ultrasound
attenuation is hardly influenced by the collective excitations.

</DOC>
<DOC>
<DOCNO> 10035 </DOCNO>
Quantum group conjecture and Stripes


  Keeping in mind our conjecture of modelling cuprates and related systems by
quantum groups and our claim that the existence of stripes is intimately
related to quantum groups and more strongly is a consequence of the underlying
quantum group structure we note that a recent claim that {\em magnetic
fluctuations} also displays a one-dimensional character makes our conjecture
more viable. The recent strong claim by Mook et al., if true further supports
our intuition. For the fluctuations associated with a striped phase are
expected to be one-dimensional, whereas the magnetic fluctuations are {\em
taken} to display two-dimensional symmetry. It is claimed by Mook et al. that
this apparent two-dimensionality results from measurements on twinned crystals,
and that similar measurements on substantial detwinned crystals of
YBa$_{2}$Cu$_{3}$O$_{6.6}$ reveal the one-dimensional character of the magnetic
fluctuations thus making the stripe scenario more stronger, in other words
there are also magnetic stripes. As noted before in our conjecture that one of
the main reason for quantum groups to model cuprates is that they are directly
related to the symmetries of one-dimensional systems. Thus now if the magnetic
fluctuations are also shown exhibiting one-dimensional behavior that all the
more {\em directly strengthens our conjecture}. However we note that our
conjecture is more generic and not tied to the one-dimensional character of the
now claimed magnetic fluctuations. Simply the one-dimesional nature of magnetic
fluctuations as noted by Mook et al., makes our conjecture more {\em obvious}
and clearer.

</DOC>
<DOC>
<DOCNO> 71555 </DOCNO>
Detection of Gravitational Waves from Inflation


  Recent measurements of temperature fluctuations in the cosmic microwave
background (CMB) indicate that the Universe is flat and that large-scale
structure grew via gravitational infall from primordial adiabatic
perturbations. Both of these observations seem to indicate that we are on the
right track with inflation. But what is the new physics responsible for
inflation? This question can be answered with observations of the polarization
of the CMB. Inflation predicts robustly the existence of a stochastic
background of cosmological gravitational waves with an amplitude proportional
to the square of the energy scale of inflation. This gravitational-wave
background induces a unique signature in the polarization of the CMB. If
inflation took place at an energy scale much smaller than that of grand
unification, then the signal will be too small to be detectable. However, if
inflation had something to do with grand unification or Planck-scale physics,
then the signal is conceivably detectable in the optimistic case by the Planck
satellite, or if not, then by a dedicated post-Planck CMB polarization
experiment. Realistic developments in detector technology as well as a proper
scan strategy could produce such a post-Planck experiment that would improve on
Planck's sensitivity to the gravitational-wave background by several orders of
magnitude in a decade timescale.

</DOC>
<DOC>
<DOCNO> 122421 </DOCNO>
Stellar Kinematics of the Spiral Structure in the Solar Neighborhood


  We present a method, based on the kinematic analysis of the Galactic disk
stars, to clarify whether the internal motions of the stellar system in spiral
arms follow those expected in the density wave theory. The method relies on the
comparison with the linear relation between the phases of spatial positions and
epicyclic motions of stars, as drawn from the theory. The application of the
method to the 78 Galactic Cepheids near the Sun, for which accurate proper
motions are available from the {\it Hipparcos} Catalogue, has revealed that
these Cepheids hold no correlation between both phases, thereby implying that
their motions are in contradiction with the theoretical predictions. Possible
reasons for this discrepancy are discussed and future prospects are outlined.

</DOC>
<DOC>
<DOCNO> 100277 </DOCNO>
Symplectic Leaves of Complex Reductive Poisson-Lie Groups


  All factorizable Lie bialgebra structures on complex reductive Lie algebras
were described by Belavin and Drinfeld. We classify the symplectic leaves of
the full class of corresponding connected Poisson-Lie groups. A formula for
their dimensions is also proved.

</DOC>
<DOC>
<DOCNO> 101591 </DOCNO>
The conjecture cr(C_m\times C_n)=(m-2)n is true for all but finitely


  It has been long congectured that the crossing number of $C_m\times C_n$ is
$(m-2)n$ for $2<m<=n$. In this paper we proved that conjecture is true for all
but finitely many $n$ for each $m$. More specifically we proved conjecture for
$n>=(m/2)((m+3)^2/2+1)$.The proof is largely based on the theory of
arrangements introduced by Adamsson and further developed by Adamsson and
Richter.

</DOC>
<DOC>
<DOCNO> 123164 </DOCNO>
Ultra-Relativistic Blast Wave: Stability and Strong Non-Universality


  Linear eigenmodes of a spherically symmetrical ultra-relativistic blast wave
(the Blandford-McKee, BMK, solution) are calculated. The BMK solution is shown
to be stable and strongly non-universal. It is stable because all the
eigenmodes decay. Non-universality of the BMK solution (BMK is not an
intermediate asymptotic) is a consequence of causality. In terms of eigenmodes
-- some eigenmodes decay too slowly. For each degree l, there exists an
eigenmode which decays at the smallest rate. The amplitude of this eigenmode,
defined as relative perturbation of energy behind the shock front, is constant
at early time. Later, when the blast wave slows down to Gamma = l/10, an
oscillatory decay commences, and the amplitude drops to less than 10% of the
initial value at Gamma = l/100. The non-universality is surprisingly strong.
Near the end of the ultra-relativistic stage, perturbations with l<200, that is
more than 10,000 different harmonics, are suppressed by less than a factor of
10. Spherical symmetry is only reached by the time the blast wave slows down to
non-relativistic velocities, when the Sedov/Taylor/von Neumann solution sets
in.

</DOC>
<DOC>
<DOCNO> 101700 </DOCNO>
The Hermitian Connection and the Jacobi Fields of a Complex Finsler


  It is proved that all invariant functions of a complex Finsler manifold can
be totally recovered from the torsion and curvature of the connection
introduced by Kobayashi for holomorphic vector bundles with complex Finsler
structures. Equations of the geodesics and Jacobi fields of a generic complex
Finsler manifold, expressed by means Kobayashi's connection, are also derived.

</DOC>
<DOC>
<DOCNO> 101964 </DOCNO>
Extension of 2-forms and symplectic varieties


  This paper deals with symplectic varieties which do not have symplectic
resolutions. Some moduli spaces of semi-stable torsion-free sheaves on a K3
surface, and symplectic V-manifolds are such varieties.
 We shall prove local Torelli theorem for symplectic varieties. Some results on
symplectic singularities are also included.

</DOC>
<DOC>
<DOCNO> 120505 </DOCNO>
The Cometary Blue Compact Dwarf Galaxies Mkn 59 and Mkn 71: Clues to


  "Cometary" Blue Compact Dwarf Galaxies (iI,C BCDs) are characterized by
off-center starbursts close to the end of an elongated dwarf irregular
(dI)-like host galaxy. This may either represent randomly enhanced star-forming
activity of a dI, or may be caused by a set of special properties of such
systems or their environment. For a first investigation of this issue, we
analyse the nearby iI,C BCDs Markarian 59 and Markarian 71. Using deep
ground-based spectrophotometric data and HST images, we derive physical
properties, structure and ages of the starburst regions and the underlying
stellar host galaxies. The metallicities show small scatter in the vicinity of
the star-forming regions and along the major axis of Mrk 59 which suggests
effective mixing of heavy elements on kpc scales. The surface brightness
profiles of the underlying host galaxies in either iI,C BCD show an exponential
decay with a central surface brightness and scale length that are intermediate
between typical iE/nE BCDs and dIs. Spectral population synthesis models in
combination with colour magnitude diagrams and colour profiles yield most
likely formation ages of ~2 Gyr for the host galaxies in both iI,C BCDs, with
upper limits of ~4 Gyr for Mrk 59 and ~3 Gyr for Mrk 71, i.e. significantly
lower than the typical age of several Gyr derived for the host galaxies of
iE/nE BCDs. These findings raise the question whether iI,C systems form a
distinct class within BCDs with respect to the age and structure of their
hosts, or whether they represent an evolutionary stage connecting young i0 BCDs
and "classical" iE/nE BCDs. Properties of analogous objects studied in the
local universe and at medium redshifts provide some support for this
evolutionary hypothesis.

</DOC>
<DOC>
<DOCNO> 9267 </DOCNO>
Tricritical behaviour in deterministic aperiodic Ising systems


  We use a mixed-spin model, with aperiodic ferromagnetic exchange interactions
and crystalline fields, to investigate the effects of deterministic geometric
fluctuations on first-order transitions and tricritical phenomena. The
interactions and the crystal field parameters are distributed according to some
two-letter substitution rules. From a Migdal-Kadanoff real-space
renormalization-group calculation, which turns out to be exact on a suitable
hierarchical lattice, we show that the effects of aperiodicity are
qualitatively similar for tricritical and simple critical behaviour. In
particular, the fixed point associated with tricritical behaviour becomes fully
unstable beyond a certain threshold dimension (which depends on the
aperiodicity), and is replaced by a two-cycle that controls a weakened and
temperature-depressed tricritical singularity.

</DOC>
<DOC>
<DOCNO> 102354 </DOCNO>
Surfaces with many nodes


  We describe smooth rational projective algebraic surfaces over an
algebraically closed field of characteristic different from 2 which contain $n
\ge \b_2-2$ disjoint smooth rational curves with self-intersection -2, where
$\b_2$ is the second Betti number. In the last section this is applied to the
study of minimal complex surfaces of general type with $p_g = 0$ and $K^2 = 8,
9$ which admit an automorphism of order 2.

</DOC>
<DOC>
<DOCNO> 169849 </DOCNO>
A Beam Splitter for Guided Atoms on an Atom Chip


  We have designed and experimentally studied a simple beam splitter for atoms
guided on an Atom Chip, using a current carrying Y-shaped wire and a bias
magnetic field. This beam splitter and other similar designs can be used to
build atom optical elements on the mesoscopic scale, and integrate them in
matterwave quantum circuits.

</DOC>
<DOC>
<DOCNO> 13585 </DOCNO>
Fluctuation Pressure of a Stack of Membranes


  We calculate the universal pressure constants of a stack of N membranes
between walls by strong-coupling theory. The results are in very good agreement
with values from Monte-Carlo simulations.

</DOC>
<DOC>
<DOCNO> 67959 </DOCNO>
The Beginning of the End of the Anthropic Principle


  We argue that if string theory as an approach to the fundamental laws of
physics is correct, then there is almost no room for anthropic arguments in
cosmology. The quark and lepton masses and interaction strengths are
determined.

</DOC>
<DOC>
<DOCNO> 10650 </DOCNO>
Pipeline model of a Fermi-sea electron pump


  The use of a band offset between the two leads of an electron pump driven by
a local oscillating voltage is shown to increase the pump current dramatically.
The structure of the electron transmission suggests the existence of dominant
inelastic channels which we call pipelines. This permits the formulation of a
simple model that gives a physical account of the numerical results for a
realistic device. A spectral analysis reveals the pump current to be carried by
scattering states with initial energy deep within the Fermi sea and not at its
surface, thereby rendering the effect insensitive to temperature. We show this
is compatible with the current flowing near the Fermi surface in the leads.

</DOC>
<DOC>
<DOCNO> 70437 </DOCNO>
Next-Order Estimate of Higgs to Two-Gluon Rate


  Using asymptotic Pade approximant methods, we have calculated the
O(alpha_s^5) contribution to the Standard-Model H to gg decay rate. This
process is of particular interest because of the slow convergence evident from
the known terms of its QCD series. The O(alpha_s^5) term is expressed as a 3rd
degree polynomial in $L= log (\frac{\mu^2}{m_t^2(\mu)})$. We find that the
asymptotic Pade predictions for the renormalization-group accessible
coefficients of L, L^2 and L^3 are within 1%, 2% and 7% of their respective
values. The inclusion of the O(alpha_s^5) contribution renders the full decay
rate virtually scale independent over the entire 0.3 M_H < mu < M_t range of
the renormalization scale mu.

</DOC>
<DOC>
<DOCNO> 72280 </DOCNO>
Three-body forces, single diffraction dissociation and shadow


  The relationships between the fundamental dynamics and diffraction phenomena
in scattering from two-body composite system are discussed. A new simple
formula for the shadow corrections to the total cross-section in scattering
from deuteron has been derived and new scaling characteristics with a clear
physical interpretation have been established. The effect of weakening the
inelastic screening at super-high energies is theoretically discovered. A
comparison with the experimental data on proton(antiproton)-deuteron total
cross-sections has been performed. It is shown that there is quite a remarkable
correspondence of the theory with the experimental data.

</DOC>
<DOC>
<DOCNO> 70953 </DOCNO>
Next-To-Leading Order Determination of Fragmentation Functions


  We analyse LEP and PETRA data on single inclusive charged hadron
cross-sections to establish new sets of Next-to-Leading order Fragmentation
Functions. Data on hadro-production of large-$p_{\bot}$ hadrons are also used
to constrain the gluon Fragmentation Function. We carry out a critical
comparison with other NLO parametrizations.

</DOC>
<DOC>
<DOCNO> 170315 </DOCNO>
Efficient Schemes for Reducing Imperfect Collective Decoherences


  We propose schemes that are efficient when each pair of qubits undergoes some
imperfect collective decoherence with different baths. In the proposed scheme,
each pair of qubits is first encoded in a decoherence-free subspace composed of
two qubits. Leakage out of the encoding space generated by the imperfection is
reduced by the quantum Zeno effect. Phase errors in the encoded bits generated
by the imperfection are reduced by concatenation of the decoherence-free
subspace with either a three-qubit quantum error correcting code that corrects
only phase errors or a two-qubit quantum error detecting code that detects only
phase errors, connected with the quantum Zeno effect again.

</DOC>
<DOC>
<DOCNO> 69831 </DOCNO>
Canonical Description of Strangeness Enhancement from p-A to Pb-Pb


  We consider the production of strange particles in Pb-Pb and p-A collisions
at the SPS energy reported by the WA97 experiment. We show that the observed
enhancement of strange baryon and antibaryon yields in Pb-Pb collisions
relative to p-Be and p-Pb can be explained in terms of the statistical model
formulated in canonical ensemble with respect to strangeness conservation. The
importance and the role of strangeness under saturation is also discussed.

</DOC>
<DOC>
<DOCNO> 83377 </DOCNO>
Learning to Filter Spam E-Mail: A Comparison of a Naive Bayesian and a


  We investigate the performance of two machine learning algorithms in the
context of anti-spam filtering. The increasing volume of unsolicited bulk
e-mail (spam) has generated a need for reliable anti-spam filters. Filters of
this type have so far been based mostly on keyword patterns that are
constructed by hand and perform poorly. The Naive Bayesian classifier has
recently been suggested as an effective method to construct automatically
anti-spam filters with superior performance. We investigate thoroughly the
performance of the Naive Bayesian filter on a publicly available corpus,
contributing towards standard benchmarks. At the same time, we compare the
performance of the Naive Bayesian filter to an alternative memory-based
learning approach, after introducing suitable cost-sensitive evaluation
measures. Both methods achieve very accurate spam filtering, outperforming
clearly the keyword-based filter of a widely used e-mail reader.

</DOC>
<DOC>
<DOCNO> 8967 </DOCNO>
Effect of incoherent scattering on shot noise correlations in the


  We investigate the effect of incoherent scattering in a Hanbury Brown and
Twiss situation with electrons in edge states of a three-terminal conductor
submitted to a strong perpendicular magnetic field. The modelization of
incoherent scattering is performed by introducing an additional voltage probe
through which the current is kept equal to zero which causes voltage
fluctuations at this probe. It is shown that inelastic scattering can lead in
this framework to positive correlations, whereas correlations remain always
negative for quasi-elastic scattering.

</DOC>
<DOC>
<DOCNO> 71367 </DOCNO>
Bounds for Lepton Flavor Violation and the Pseudoscalar Higgs in the


  Current experimental data from the $g-2$ muon factor, seems to show the
necessity of physics beyond the Standard Model (SM), since the difference
between SM and experimental predictions is 2.6$\sigma $. In the framework of
the General Two Higgs Doublet Model (2HDM), we calculate the muon anomalous
magnetic moment to get lower and upper bounds for the Flavour Changing (FC)
Yukawa couplings in the leptonic sector. We also obtain lower bounds for the
mass of the pseudoscalar Higgs ($m_{A^0}$) as a function of the parameters of
the model.

</DOC>
<DOC>
<DOCNO> 170714 </DOCNO>
Feasible Entanglement Purification for Quantum Communication


  The distribution of entangled states between distant locations will be
essential for the future large scale realization of quantum communication
schemes such as quantum cryptography and quantum teleportation. Because of the
unavoidable noise in the quantum communication channel, the entanglement
between two particles is more and more degraded the further they propagate.
Entanglement purification is thus essential to distill highly entangled states
from less entangled ones. Existing general purification protocols are based on
the quantum controlled-NOT (CNOT) or similar quantum logic operations, which
are very difficult to implement experimentally. Present realizations of CNOT
gates are much too imperfect to be useful for long-distance quantum
communication. Here we present a feasible scheme for the entanglement
purification of general mixed entangled states, which does not require any CNOT
operations, but only simple linear optical elements. Since the perfection of
such elements is very high, the local operations necessary for purification can
be performed with the required precision. Our procedure is within the reach of
current technology and should significantly simplify the implementation of
long-distance quantum communication.

</DOC>
<DOC>
<DOCNO> 117914 </DOCNO>
Electron acceleration due to high frequency instabilities at supernova


  Observations of synchrotron radiation across a wide range of wavelengths
provide clear evidence that electrons are accelerated to relativistic energies
in supernova remnants (SNRs). However, a viable mechanism for the
pre-acceleration of such electrons to mildly relativistic energies has not yet
been established. In this paper an electromagnetic particle-in-cell (PIC) code
is used to simulate acceleration of electrons from background energies to tens
of keV at perpendicular collisionless shocks associated with SNRs. Free energy
for electron energization is provided by ions reflected from the shock front,
with speeds greater than the upstream electron thermal speed. The PIC
simulation results contain several new features, including: the acceleration,
rather than heating, of electrons via the Buneman instability; the acceleration
of electrons to speeds exceeding those of the shock-reflected ions producing
the instability; and strong acceleration of electrons perpendicular to the
magnetic field. Electron energization takes place through a variety of resonant
and non-resonant processes, of which the strongest involves stochastic
wave-particle interactions. In SNRs the diffusive shock process could then
supply the final step required for the production of fully relativistic
electrons. The mechanisms identified in this paper thus provide a possible
solution to the electron pre-acceleration problem.

</DOC>
<DOC>
<DOCNO> 152414 </DOCNO>
Chern-Simons Particles with Nonstandard Gravitational Interaction


  The model of nonrelativistic particles coupled to nonstandard (2+1)-gravity
[1] is extended to include Abelian or non-Abelian charges coupled to
Chern-Simons gauge fields. Equivalently, the model may be viewed as describing
the (Abelian or non-Abelian) anyonic dynamics of Chern-Simons particles
coupled, in a reparametrization invariant way, to a translational Chern-Simons
action. The quantum two-body problem is described by a nonstandard
Schr\"{o}dinger equation with a noninteger angular momentum depending on energy
as well as particle charges. Some numerical results describing the modification
of the energy levels by these charges in the confined regime are presented. The
modification involves a shift as well as splitting of the levels.

</DOC>
<DOC>
<DOCNO> 85153 </DOCNO>
How much of the outgoing radiation can be intercepted by


  The Schwarzschild spacetime is for electromagnetic waves like a nonuniform
medium with a varying refraction index. A fraction of an outgoing radiation
scatters off the curvature of the geometry and can be intercepted by a
gravitational center. The amount of the intercepted energy is bounded above by
the backscattered energy of an initially outgoing pulse of electromagnetic
radiation, which in turn depends on the initial energy, the Schwarzschild
radius and the pulse location. Its magnitude depends on the frequency spectrum:
it becomes negligible in the short wave limit but can be significant in the
long wave regime.

</DOC>
<DOC>
<DOCNO> 150981 </DOCNO>
On the stringy nature of winding modes in noncommutative thermal field


  We show that thermal noncommutative field theories admit a version of
`channel duality' reminiscent of open/closed string duality, where non-planar
thermal loops can be replaced by an infinite tower of tree-level exchanges of
effective fields. These effective fields resemble closed strings in three
aspects: their mass spectrum is that of closed-string winding modes, their
interaction vertices contain extra moduli, and they can be regarded as
propagating in a higher-dimensional `bulk' space-time. In noncommutative models
that can be embedded in a D-brane, we show the precise relation between the
effective `winding fields' and closed strings propagating off the D-brane. The
winding fields represent the coherent coupling of the infinite tower of
closed-string oscillator states. We derive a sum rule that expresses this
effective coupling in terms of the elementary couplings of closed strings to
the D-brane. We furthermore clarify the relation between the effective
propagating dimension of the winding fields and the true codimension of the
D-brane.

</DOC>
<DOC>
<DOCNO> 170108 </DOCNO>
Efficient Linear Optics Quantum Computation


  We investigate the computational power of passive and active linear optical
elements and photo-detectors. We show that single photon sources, passive
linear optics and photo-detectors are sufficient for implementing reliable
quantum algorithms. Feedback from the detectors to the optical elements is
required for this implementation. Without feedback, non-deterministic quantum
computation is possible. A single photon source sufficient for quantum
computation can be built with an active linear optical element (squeezer) and a
photo-detector. The overheads associated with using only linear optics appear
to be sufficiently low to make quantum computation based on our proposal a
viable alternative.

</DOC>
<DOC>
<DOCNO> 100066 </DOCNO>
Heteroclinic orbits, mobility parameters and stability for thin film


  We study numerically the phase space of the evolution equation h_t = -(h^n
h_{xxx})_x - B (h^m h_x)_x . Here h(x,t) is nonnegative, n>0 and m is real, and
the Bond number B is positive.
  We pursue three goals: to investigate the nonlinear stability of the positive
periodic and constant steady states; to locate heteroclinic connecting orbits
between these steady states and the compactly supported 'droplet' steady
states; and to determine how these orbits change when the 'mobility' exponents
n and m are changed.
  For example, we change the mobility coefficients in such a way that the
steady states are unchanged and find evidence that heteroclinic orbits between
steady states are perturbed but not broken. We also find that when there appear
to be touch-down singularities, the exponent n affects whether they occur in
finite or infinite time. It also can affect whether there is one touch-down or
two touch-downs per period.

</DOC>
<DOC>
<DOCNO> 174548 </DOCNO>
Breakup time scale studied in the 8 GeV/c pi- + 197Au reaction


  Experimental data from the reaction of an 8.0 GeV/c pi- beam incident on a
197Au target have been analyzed in order to investigate the integrated breakup
time scale for hot residues. Alpha-particle energy spectra and particle angular
distributions supported by a momentum tensor analysis suggest that at large
excitation energy, above 3-5 MeV/nucleon, light-charged particles are emitted
prior to or at the same time as the emission of the heavy fragments. Comparison
with the SMM and GEMINI models is presented. A binary fission-like mechanism
fits the experimental data at low excitation energies, but seems unable to
reproduce the data at excitation energies above 3-5 MeV/nucleon.

</DOC>
<DOC>
<DOCNO> 80583 </DOCNO>
The 1 Teraflops QCDSP computer


  The QCDSP computer (Quantum Chromodynamics on Digital Signal Processors) is
an inexpensive, massively parallel computer intended primarily for simulations
in lattice gauge theory. Currently, two large QCDSP machines are in full-time
use: an 8,192 processor, 0.4 Teraflops machine at Columbia University and an
12,288 processor, 0.6 Teraflops machine at the RIKEN-BNL Research Center at
Brookhaven National Laboratory. We describe the design process, architecture,
software and current physics projects of these computers.

</DOC>
<DOC>
<DOCNO> 116693 </DOCNO>
Singularities in kinetic theory


  It is revealed that distribution functions of practical gases relate to
singularities and such singularities can, with molecular motion, spread to the
entire region of interest. It is also shown that even common continuous
distribution functions involve a similar quasi-discontinuity difficulty.

</DOC>
<DOC>
<DOCNO> 69708 </DOCNO>
Pion-nucleon scattering in an effective chiral field theory with


  We analyze elastic-pion nucleon scattering to third order in the so-called
small scale expansion. It is based on an effective Lagrangian including pions,
nucleons and deltas as active degrees of freedom and counting external momenta,
the pion mass and the nucleon-delta mass splitting as small parameters. The
fermion fields are considered as very heavy. We present results for phase
shifts, threshold parameters and the sigma term. We discuss the convergence of
the approach. A detailed comparison with results obtained in heavy baryon
chiral perturbation theory to third and fourth order is also given.

</DOC>
<DOC>
<DOCNO> 120667 </DOCNO>
Spectrum and proper motion of a brown dwarf companion of the T Tauri


  We present optical and infrared spectra as well as the proper motion of an
H=12 mag object 2" off the ~5 mag brighter spectroscopic binary star CoD-33
7795 (=TWA-5), a member of the TW Hya association of T Tauri stars at ~55 pc.
It was suggested as companion candidate by Lowrance et al. (1999) and Webb et
al. (1999), but neither a spectrum nor the proper motion of the faint object
were available before. Our spectra taken with FORS2 and ISAAC at the ESO-VLT
reveal that the companion candidate has spectral type M8.5 to M9. It shows
strong H-alpha emission and weak Na I absorption, both indicative of a young
age. The faint object is clearly detected and resolved in our optical and
infrared images, with a FWHM of 0.18" in the FORS2 image. The faint object's
proper motion, based on two year epoch difference, is consistent with the
proper motion of CoD-33 7795 by 5 Gaussian sigma significance. From three
different theoretical pre-main sequence models, we estimate the companion mass
to be between ~15 and 40 M_jup, assuming the distance and age of the primary. A
slight offset between the VLT and HST images with an epoch difference of two
years can be interpreted as orbital motion. The probability for chance
alignment of such a late-type object that close to CoD-33 7795 with the correct
proper motion is below 7e-9. Hence, the faint object is physically associated
with CoD-33 7795, the 4th brown dwarf companion around a normal star confirmed
by both spectrum and proper motion, the first around a pre-main sequence star.

</DOC>
<DOC>
<DOCNO> 123027 </DOCNO>
Far Ultraviolet Spectra of B Stars near the Ecliptic


  Spectra of B stars in the wavelength range of 911-1100 A have been obtained
with the EURD spectrograph onboard the Spanish satellite MINISAT-01 with ~5 A
spectral resolution. IUE spectra of the same stars have been used to normalize
Kurucz models to the distance, reddening and spectral type of the corresponding
star. The comparison of 8 main-sequence stars studied in detail (alpha Vir,
epsilon Tau, lambda Tau, tau Tau, alpha Leo, zeta Lib, theta Oph, and sigma
Sgr) shows agreement with Kurucz models, but observed fluxes are 10-40% higher
than the models in most cases. The difference in flux between observations and
models is higher in the wavelength range between Lyman alpha and Lyman beta. We
suggest that Kurucz models underestimate the FUV flux of main-sequence B stars
between these two Lyman lines. Computation of flux distributions of
line-blanketed model atmospheres including non-LTE effects suggests that this
flux underestimate could be due to departures from LTE, although other causes
cannot be ruled out. We found the common assumption of solar metallicity for
young disk stars should be made with care, since small deviations can have a
significant impact on FUV model fluxes. Two peculiar stars (rho Leo and epsilon
Aqr), and two emission line stars (epsilon Cap and pi Aqr) were also studied.
Of these, only epsilon Aqr has a flux in agreement with the models. The rest
have strong variability in the IUE range and/or uncertain reddening, which
makes the comparison with models difficult.

</DOC>
<DOC>
<DOCNO> 70285 </DOCNO>
Possible violation of Newtonian gravitational law at small distances and


  The recent ideas that the gravitational and gauge interactions become united
at the weak scale lead to Yukawa-type corrections to the Newtonian
gravitational law at small distances. We briefly summarize the best constraints
on these corrections obtained recently from the experiments on the measurement
of the Casimir force. The new constraints on the Yukawa-type interaction are
derived from the latest Casimir force measurement between a large gold coated
sphere and flat disk using an atomic force microscope. The obtained constraints
are stronger up to 19 times comparing the previous experiment with aluminum
surfaces and up to 4500 times comparing the Casimir force measurements between
dielectrics. The application range of constraints obtained by means of an
atomic force microscope is extended.

</DOC>
<DOC>
<DOCNO> 152098 </DOCNO>
AdS/CFT and Randall-Sundrum Model Without a Brane


  We reformulate the Randall-Sundrum (RS) model on the compactified AdS by
adding a term proportional to the area of the boundary to the usual gravity
action with a negative cosmological constant and show that gravity can still be
localized on the boundary without introducing singular brane sources. The
boundary conditions now follow from the field equations, which are obtained by
letting the induced metric vary on the boundary. This approach gives similar
modes that are obtained in [1] and clarifies the complementarity of the RS and
the AdS/CFT pictures. Normalizability of these modes is checked by an
inner-product in the space of linearized perturbations. The same conclusions
hold for a massless scalar field in the bulk.

</DOC>
<DOC>
<DOCNO> 101478 </DOCNO>
Bounded Point Evaluations and Local Spectral Theory


  We study in this paper the concept of bounded point evaluations for cyclic
operators. We give a negative answer to a question of L.R. Williams {\it
Dynamic Systems and Apllications} 3(1994) 103-112. Furthermore, we generalize
some results of Williams and give a simple proof of theorem 2.5 of L.R.
Williams (The Local Spectra of Pure Quasinormal Operators J. Math. anal. Appl.
187(1994) 842-850) that non normal hyponormal weighted shifts have fat local
spectra.

</DOC>
<DOC>
<DOCNO> 120019 </DOCNO>
Constraints from Dynamical Friction on the Dark Matter Content of Barred


  We show that bars in galaxy models having halos of moderate density and a
variety of velocity distributions all experience a strong drag from dynamical
friction unless the halo has large angular momentum in the same sense as the
disk. The frictional drag decreases the bar pattern speed, driving the
corotation point out to distances well in excess of those estimated in barred
galaxies. The halo angular momentum required to avoid strong braking is
unrealistically large, even when rotation is confined to the inner halo only.
We conclude, therefore, that bars are able to maintain their observed high
pattern speeds only if the halo has a central density low enough for the disk
to provide most of the central attraction in the inner galaxy. We present
evidence that this conclusion holds for all bright galaxies.

</DOC>
<DOC>
<DOCNO> 150633 </DOCNO>
Poisson algebra of 2d dimensionally reduced gravity


  Using a Lax pair based on twisted affine $sl(2,R)$ Kac-Moody and Virasoro
algebras, we deduce a r-matrix formulation of two dimensional reduced vacuum
Einstein's equations. Whereas the fundamental Poisson brackets are
non-ultralocal, they lead to pure c-number modified Yang-Baxter equations. We
also describe how to obtain classical observables by imposing reasonable
boundaries conditions.

</DOC>
<DOC>
<DOCNO> 121337 </DOCNO>
The Diverse Population of ULIRGs


  We present results from an on-going Hubble Space Telescope (HST) survey of a
large sample of ULIRGs (Ultra-Luminous IR Galaxies). New ground-based
observations are now being used to complement the HST data and to assist in the
interpretation of these complex objects. A rich spectroscopic, morphological,
and dynamical diversity is found within the ULIRG population, nearly 100% of
which are merger and/or collision remnants. The consequences of this diversity
may apply to the interpretation of distant submm/FIR sources and their
subsequent evolution.

</DOC>
<DOC>
<DOCNO> 83060 </DOCNO>
Predicting the expected behavior of agents that learn about agents: the


  We describe a framework and equations used to model and predict the behavior
of multi-agent systems (MASs) with learning agents. A difference equation is
used for calculating the progression of an agent's error in its decision
function, thereby telling us how the agent is expected to fare in the MAS. The
equation relies on parameters which capture the agent's learning abilities,
such as its change rate, learning rate and retention rate, as well as relevant
aspects of the MAS such as the impact that agents have on each other. We
validate the framework with experimental results using reinforcement learning
agents in a market system, as well as with other experimental results gathered
from the AI literature. Finally, we use PAC-theory to show how to calculate
bounds on the values of the learning parameters.

</DOC>
<DOC>
<DOCNO> 100589 </DOCNO>
Integration with respect to Euler characteristic over the


  We discuss a notion of integration with respect to the Euler characteristic
in the projectivization $\P{\cal O}_{\C^n,0}$ of the ring ${\cal O}_{\C^n,0}$
of germs of functions on $C^n$ and show that the Alexander polynomial and the
zeta-function of a plane curve singularity can be expressed as certain
integrals over $\P{\cal O}_{\C^2,0}$ with respect to the Euler characteristic.

</DOC>
<DOC>
<DOCNO> 100163 </DOCNO>
Morita equivalences of Ariki-Koike algebras


  We prove that every Ariki-Koike algebra is Morita equivalent to a direct sum
of tensor products of smaller Ariki-Koike algebras which have q-connected
parameter sets. A similar result is proved for the cyclotomic q-Schur algebras.
Combining our results with work of Ariki and Uglov, the decomposition numbers
for the Ariki-Koike algebras defined over fields of characteristic zero are now
known in principle.

</DOC>
<DOC>
<DOCNO> 80939 </DOCNO>
Constructing Improved Overlap Fermions in QCD


  We describe an explicit construction of approximate Ginsparg-Wilson fermions
for QCD. We use ingredients of perfect action origin, and further elements. The
spectrum of the lattice Dirac operator reveals the quality of the
approximation. We focus on beta =6 for optimisation. Such fermions are intended
to be inserted into the overlap formula. Hence we also test the speed of
convergence under polynomial evaluation of the overlap formula.

</DOC>
<DOC>
<DOCNO> 39640 </DOCNO>
Status of Experiments and Recent Results from CMD-2 Detector at Vepp-2M


  The Cryogenic Magnetic Detector (CMD-2) is shortly described. Preliminary
results for the cross sections of $e^+$ $e^-$ annihilation into hadrons and
leptons are presented in the c.m. energy range from 0.37 to 1.39 GeV. The total
integrated luminosity of about 26 ${pb}^{-1}$ has been collected. The new
results for the $\rho$ and $\omega$ meson parameters are reported. The major
decay modes of the $\phi$ meson as well as its rare decays have been observed.

</DOC>
<DOC>
<DOCNO> 118727 </DOCNO>
Angular Momentum Transport in Particle and Fluid Disks


  We examine the angular momentum transport properties of disks composed of
macroscopic particles whose velocity dispersions are externally enhanced
(``stirred''). Our simple Boltzmann equation model serves as an analogy for
unmagnetized fluid disks in which turbulence may be driven by thermal
convection. We show that interparticle collisions in particle disks play the
same role as fluctuating pressure forces and viscous dissipation in turbulent
disks: both transfer energy in random motions associated with one direction to
those associated with another, and convert kinetic energy into heat. The
direction of angular momentum transport in stirred particle and fluid disks is
determined by the direction of external stirring and by the properties of the
collision term in the Boltzmann equation (or its analogue in the fluid
problem). In particular, our model problem yields inward transport for
vertically or radially stirred disks, provided collisions are suitably
inelastic; the transport is outwards in the elastic limit. Numerical
simulations of hydrodynamic turbulence driven by thermal convection find inward
transport; this requires that fluctuating pressure forces do little to no work,
and is analogous to an externally stirred particle disk in which collisions are
highly inelastic.

</DOC>
<DOC>
<DOCNO> 8629 </DOCNO>
Charge cross-over at the U(1)-Higgs phase transition


  The type-I region of phase transitions at finite temperature of the
U(1)-Higgs theory in 3+1 dimensions is investigated in detail using a Wilsonian
renormalisation group. We consider in particular the quantitative effects
induced through the cross-over of the scale-dependent Abelian charge from the
Gaussian to a non-trivial Abelian fixed point. As a result, the strength of the
first-order phase transition is weakened. Analytical solutions to approximate
flow equations are obtained, and all characteristics of the phase transition
are discussed and compared to the results obtained from perturbation theory. In
addition, we present a detailed quantitative study regarding the dependence of
the physical observables on the coarse-graining scheme. This results in
error-bars for the regularisation scheme (RS) dependence. We find quantitative
evidence for an intimate link between the RS dependence and truncations of flow
equations.

</DOC>
<DOC>
<DOCNO> 118844 </DOCNO>
Membership and Multiplicity among Very Low-Mass Stars and Brown Dwarfs


  We present near-infrared photometry and optical spectroscopy of very low-mass
stars and brown dwarf candidates in the Pleiades open cluster. The membership
status of these objects is assessed. Eight objects out of 45 appear to be
non-members. A search for companions among 34 very low-mass Pleiades members
(M$\le$0.09 M$_\odot$) in high-spatial resolution images obtained with the
Hubble Space Telescope and the adaptive optics system of the
Canada-France-Hawaii telescope produced no resolved binaries with separations
larger than 0.2 arcsec (a ~ 27 AU; P ~ 444 years). Nevertheless, we find
evidence for a binary sequence in the color-magnitude diagrams, in agreement
with the results of Steele & Jameson (1995) for higher mass stars. We compare
the multiplicity statistics of the Pleiades very low-mass stars and brown
dwarfs with that of G and K-type main sequence stars in the solar neighborhood
(Duquennoy & Mayor 1991). We find that there is some evidence for a deficiency
of wide binary systems (separation >27 AU) among the Pleiades very low-mass
members. We briefly discuss how this result can fit with current scenarios of
brown dwarf formation. We correct the Pleiades substellar mass function for the
contamination of cluster non-members found in this work. We find a
contamination level of 33% among the brown dwarf candidates identified by
Bouvier et al. (1998). Assuming a power law IMF across the substellar boundary,
we find a slope dN/dM ~ M^{-0.53}, implying that the number of objects per mass
bin is still rising but the contribution to the total mass of the cluster is
declining in the brown dwarf regime.

</DOC>
<DOC>
<DOCNO> 9444 </DOCNO>
Fast fluctuating fields as the source of low-frequency conductance


  It is shown that in many-electron systems quantum transfer amplitudes and
thus transfer probabilities may be strongly influenced by fast fluctuating
fields, in particular, caused by simultaneous electron transfers. Corresponding
mutual interplay of many electron jumps, arising at the fundamental level of
quantum phases, results in long-correlated (1/f type) conductance fluctuations.
However, thats could not be theoretically catched if neglect the real
discreteness of quantum energy spectra and use the continuous spectrum
approximation when building kinetic theory. Basing on first principles, the
estimates of low-frequency fluctuations of tunneling conductance are presented.

</DOC>
<DOC>
<DOCNO> 170217 </DOCNO>
Performances of Block Codes Attaining the Expurgated and Cutoff Rate


  A conceptually simple method for derivation of lower bounds on the error
exponent of specific families of block codes used on classical-quantum channels
with arbitrary signal states over a finite Hilbert space is presented. It is
shown that families of binary block codes with appropriately rescaled binomial
multiplicity enumerators used on binary classical-quantum channels and decoded
by the suboptimal decision rule introduced by Holevo attain the expurgated and
cutoff rate lower bounds on the error exponent.

</DOC>
<DOC>
<DOCNO> 8779 </DOCNO>
Conductivity activation energy for bilayer hetero-structures at integer


  We report on study of low-energy excitations in a bilayer hetero-structure 2D
electron gas. We split the bilayer Hamiltonian into SU(4)-symmetric part and
the anisotropy part and treat the latter as a perturbation. We find that both
Goldstone and the charged excitations - skyrmions - are goverened by the
non-linear Sigma Model. We calculate the anisotropic energy gap of the skyrmion
to have a prominent minimum in the canted antiferromagnetic phase of bilayer.
We compare our findings with the results of recent experiments.

</DOC>
<DOC>
<DOCNO> 100909 </DOCNO>
Pseudo-effective line bundles on compact K\"ahler manifolds


  The goal of this work is to pursue the study of pseudo-effective line bundles
and vector bundles. Our first result is a generalization of the Hard Lefschetz
theorem for cohomology with values in a pseudo-effective line bundle. The
Lefschetz map is shown to be surjective when (and, in general, only when) the
pseudo-effective line bundle is twisted by its multiplier ideal sheaf. This
result has several geometric applications, e.g. to the study of compact
K\"ahler manifolds with pseudo-effective canonical or anti-canonical line
bundles. Another concern is to understand pseudo-effectivity in more algebraic
terms. In this direction, we introduce the concept of an "almost" nef line
bundle, and mean by this that the degree of the bundle is nonnegative on
sufficiently generic curves. It can be shown that pseudo-effective line bundles
are almost nef, and our hope is that the converse also holds true. This can be
checked in some cases, e.g. for the canonical bundle of a projective 3-fold.
  From this, we derive some geometric properties of the Albanese map of compact
K\"ahler 3-folds.

</DOC>
<DOC>
<DOCNO> 9521 </DOCNO>
Study of Macroscopic Coherence and Decoherence in the SQUID by Adiabatic


  We suggest a procedure for demonstrating quantum coherence and measuring
decoherence times between different fluxoid states of a SQUID by using
``adiabatic inversion'', where one macroscopic fluxoid state is smoothly
transferred into the other, like a spin reversing direction by following a
slowly moving magnetic field. This is accomplished by sweeping an external
applied flux, and depends on a well-defined quantum phase between the two
macroscopic states. Varying the speed of the sweep relative to the decoherence
time permits one to move from the quantum regime, where such a well-defined
phase exists, to the classical regime where it is lost and the inversion is
inhibited. Thus observing whether inversion has taken place or not as a
function of sweep speed offers the possibility of measuring the decoherence
time. The main requirement for the feasibility of the scheme appears to be that
the low temperature relaxation time among the quantum levels of the SQUID be
long compared to other time scales of the problem.
 Applications to the ``quantum computer'', with the level system of the SQUID
playing the role of the qbit, are briefly discussed.

</DOC>
<DOC>
<DOCNO> 68323 </DOCNO>
Natural Effective Supersymmetry


  Much heavier sfermions of the first-two generations than the other
superparticles provide a natural explanation for the flavor and CP problems in
the supersymmetric standard model (SUSY SM). However, the heavy sfermions may
drive the mass squareds for the light third generation sfermions to be negative
through two-loop renormalization group (RG) equations, breaking color and
charge. Introducing extra matters to the SUSY SM, it is possible to construct
models where the sfermion masses are RG invariant at the two-loop level in the
limit of vanishing gaugino-mass and Yukawa-coupling contributions. We calculate
the finite corrections to the light sfermion masses at the two-loop level in
the models. We find that the finite corrections to the light-squark mass
squareds are negative and can be less than (0.3-1)% of the heavy-squark mass
squareds, depending on the number and the parameters of the extra matters. We
also discuss whether such models realized by the U(1)_X gauge interaction at
the GUT scale can satisfy the constraints from \Delta m_K and \epsilon_K
naturally. When both the left- and right-handed down-type squarks of the
first-two generations have common U(1)_X charges, the supersymmetric
contributions to \Delta m_K and \epsilon_K are sufficiently suppressed without
spoiling naturalness, even if the flavor-violating supergravity contributions
to the sfermion mass matrices are included. When only the right-handed squarks
of the first-two generations have a common U(1)_X charge, we can still satisfy
the constraint from \Delta m_K naturally, but evading the bound from \epsilon_K
requires the CP phase smaller than 10^{-2}.

</DOC>
<DOC>
<DOCNO> 101284 </DOCNO>
State transitions as morphisms for complete lattices


  We enlarge the hom-sets of categories of complete lattices by introducing
`state transitions' as generalized morphisms. The obtained category will then
be compared with a functorial quantaloidal enrichment and a contextual
quantaloidal enrichment that uses a specific concretization in the category of
sets and partially defined maps ($Parset$).

</DOC>
<DOC>
<DOCNO> 67903 </DOCNO>
Intermediate-Mass Dileptons at the CERN-SpS and RHIC


  The significance of thermal dilepton radiation at intermediate invariant
masses (1GeV<M<3GeV) in ultrarelativistic heavy-ion collisions is investigated.
At CERN-SpS energies, a consistent explanation of the excess observed by NA50
can be given. At RHIC energies the thermal signal is dominated by early
emission indicative for QGP formation. Chemical under-saturation effects and
the competition with open-charm contributions are addressed.

</DOC>
<DOC>
<DOCNO> 151124 </DOCNO>
On Charged Strings and their Networks


  We investigate properties of several string networks in $D < 10$ which carry
electric currents as well as electrostatic charge densities. We show the
electric-current conservations as well as the force-balance condition of the
string tensions on 3-string junctions in these networks. We also show the
consistency of the above string networks from their world-volume point of view
by comparing the world-volume energy-density with the induced worldsheet energy
density of the supergravity solution. Finally, we present new charged
macroscopic string solutions in type II theories in D=8 and discuss certain
issues related to their network construction.

</DOC>
<DOC>
<DOCNO> 122548 </DOCNO>
Radio Supernova 1987A at 843 MHz


  We report the flux densities of the evolving radio source SN1987A at 843 MHz
measured from observations made with the Molonglo Observatory Synthesis
Telescope between 1994 September and 2000 May. The radio light curve shows that
the rate of increase of the flux density jumped markedly around days 2800-3000
(i.e. in the first half of 1995), and that since then the radio evolution has
been remarkably well fitted by a simple linear increase of (62.7 +- 0.5)
microJansky/day. We discuss in detail the relationship between the radio light
curve and the recent brightening of the system at optical wavelengths.

</DOC>
<DOC>
<DOCNO> 8420 </DOCNO>
Statistical mechanics approach to the phase unwrapping problem


  The use of Mean-Field theory to unwrap principal phase patterns has been
recently proposed. In this paper we generalize the Mean-Field approach to
process phase patterns with arbitrary degree of undersampling. The phase
unwrapping problem is formulated as that of finding the ground state of a
locally constrained, finite size, spin-L Ising model under a non-uniform
magnetic field. The optimization problem is solved by the Mean-Field Annealing
technique. Synthetic experiments show the effectiveness of the proposed
algorithm.

</DOC>
<DOC>
<DOCNO> 102878 </DOCNO>
Real regulators on Milnor complexes


  We give an explicit description of a real regulator from the cohomology of a
Milnor complex associated to a projective algebraic manifold, to a certain
quotient of Deligne cohomology.

</DOC>
<DOC>
<DOCNO> 118686 </DOCNO>
Advection-Dominated Accretion with Infall and Outflows


  We present self-similar solutions for advection-dominated accretion flows
with radial viscous force in the presence of outflows from the accretion flow
or infall. The axisymmetric flow is treated in variables integrated over polar
sections and the effects of infall and outflows on the accretion flow are
parametrised for possible configurations compatible with the self-similar
solution. We investigate the resulting accretion flows for three different
viscosity laws and derive upper limits on the viscosity parameter alpha. In
addition, we find a natural connection to non-rotating and spherical accretion
with turbulent viscosity, which is assumed to persist even without differential
rotation. Positive Bernoulli numbers for advection-dominated accretion allow a
fraction of the gas to be expelled in an outflow and the upper limit on the
viscosity predicts that outflows are inevitable for equations of state close to
an ideal gas.

</DOC>
<DOC>
<DOCNO> 69142 </DOCNO>
The so-called renormalization group method applied to the specific prime


  A so-called Renormalization Group (RG) analysis is performed in order to shed
some light on why the density of prime numbers in $\Bbb N^*$ decreases like the
single power of the inverse neperian logarithm.

</DOC>
<DOC>
<DOCNO> 68107 </DOCNO>
HERA Constraint on Warped Quantum Gravity


  We study recent data on deep inelastic e^+ p scattering at HERA to constrain
the parameters of a Randall-Sundrum-type scenario of quantum gravity with a
small extra dimension and a non-factorable geometry.

</DOC>
<DOC>
<DOCNO> 8619 </DOCNO>
Some remarks on the interpretation of degree of nonextensivity


  Recently we have demostrated that the nonextensitivity parameter q occuring
in some applications of Tsallis statistics (known also as index of the
corresponding L\'evy distribution) is, in the q>1 case, given entirely by the
fluctuations of the parameters of the usual exponential distribution. We show
here that this interpretation is valid also for the q<1 case. The parameter q
is therefore a measure of fluctuations of the parameters of the usual
exponential distribution.

</DOC>
<DOC>
<DOCNO> 40479 </DOCNO>
Observation of the Askaryan Effect: Coherent Microwave Cherenkov


  We present the first direct experimental evidence for the charge excess in
high energy particle showers predicted nearly 40 years ago by Askaryan. We
directed bremsstrahlung photons from picosecond pulses of 28.5 GeV electrons at
the SLAC Final Focus Test Beam facility into a 3.5 ton silica sand target,
producing electromagnetic showers several meters long. A series of antennas
spanning 0.3 to 6 GHz were used to detect strong, sub-nanosecond radio
frequency pulses produced whenever a shower was present. The measured electric
field strengths are consistent with a completely coherent radiation process.
The pulses show 100% linear polarization, consistent with the expectations of
Cherenkov radiation. The field strength versus depth closely follows the
expected particle number density profile of the cascade, consistent with
emission from excess charge distributed along the shower. These measurements
therefore provide strong support for experiments designed to detect high energy
cosmic rays and neutrinos via coherent radio emission from their cascades.

</DOC>
<DOC>
<DOCNO> 120448 </DOCNO>
A study of the dipping low mass X-ray binary X\th 1624-490 from the


  A study of the luminous dipping LMXB X1624-490 was made using BeppoSAX. From
modelling the MECS radial profile in several energy bands, the optical depth to
dust scattering at 1 keV was found to be 2.4+/-0.4. The non-dip and dip spectra
of X1624-490 in the energy band 1-100 keV are well-described by emission
consisting of a point-like blackbody from the neutron star plus extended
Comptonized emission from an ADC. The blackbody temperature was 1.31+/-0.07 keV
and the Comptonized emission had photon power law index 2.0+0.5/-0.7 and
cut-off energy ~12 keV. Good fits to the dip spectra were obtained by allowing
the Comptonized emission to be progressively covered by an extended absorber
while the blackbody was rapidly absorbed and a constant halo component
accounted for dust scattering into the line-of-sight. From the dip ingress
time, a diameter of the extended Comptonized emission region of 5.3+/-0.8x10^10
cm was derived, consistent with a hot, X-ray emitting corona extending to ~50%
of the accretion disk radius. The source luminosity for a distance of 15 kpc is
7.3x10^37 erg/s, an appreciable fraction of the Eddington limit making
X1624-490 the most luminous dipping LMXB. The half-height of the blackbody
emitting region on the neutron star of 6.8+/-1.8 km agrees well with the
half-height of the radiatively supported inner accretion disk of 6.3+/-2.9 km.
Together with similar agreement recently obtained for 13 other LMXB in an ASCA
survey (Church & Balucinska-Church 2000), this strongly supports the
identification of the neutron star as the origin of the blackbody emission in
LMXB and suggests a mechanism in which the disk height is the main factor
determining the level of blackbody emission. Finally, from RXTE ASM data, we
derive an improved orbital period of 20.87+/-0.01 hr.

</DOC>
<DOC>
<DOCNO> 68913 </DOCNO>
Chiral Symmetry Restoration at Nonzero Temperature in the SU(3) \times


  We study patterns of chiral symmetry breaking at zero temperature and its
subsequent restoration at nonzero temperature within the $SU(3)_{r} \times
SU(3)_{\ell}$ linear sigma model. Gap equations for the masses of the scalar
and pseudoscalar mesons and the non-strange and strange quark condensates are
systematically derived in the Hartree approximation via the
Cornwall-Jackiw-Tomboulis formalism. In the chiral limit, the chiral symmetry
restoring transition is found to be first order, as predicted by universality
arguments. Taking the experimental values for the meson masses, however, the
transition is crossover. The absence of the $U(1)_A$ anomaly is found to drive
this transition closer to being first order. At large temperatures, the mixing
angles between octet and singlet states approach ideal flavor mixing.

</DOC>
<DOC>
<DOCNO> 151600 </DOCNO>
The Cosmological Constant in Calabi-Yau 3-fold Compactifications of the


  Brane world scenarios offer a way of setting the cosmological constant to
zero after supersymmetry breaking provided there is a sufficient number of
adjustable integration constants/parameters. In the case of the Horava-Witten
theory compactified on a Calabi-Yau threefold, we argue that it is difficult to
find enough freedom to get a zero (or small) cosmological constant after
supersymmetry breaking.

</DOC>
<DOC>
<DOCNO> 119093 </DOCNO>
The effects of a Variable IMF on the Chemical Evolution of the Galaxy


  In this work we explore the effects of adopting an initial mass function
(IMF) variable in time on the chemical evolution of the Galaxy. In order to do
that we adopt a chemical evolution model which assumes two main infall episodes
for the formation of the Galaxy. We study the effects on such a model of
different IMFs. First, we use a theoretical one based on the statistical
description of the density field arising from random motions in the gas. This
IMF is a function of time as it depends on physical conditions of the site of
star formation. We also investigate the behaviour of the model predictions
using other variable IMFs, parameterized as a function of metallicity. Our
results show that the theoretical IMF when applied to our model depends on time
but such time variation is important only in the early phases of the Galactic
evolution, when the IMF is biased towards massive stars. We also show that the
use of an IMF which is a stronger function of time does not lead to a good
agreement with the observational constraints suggesting that if the IMF varied
this variation should have been small. Our main conclusion is that the G-dwarf
metallicity distribution is best explained by infall with a large timescale and
a constant IMF, since it is possible to find variable IMFs of the kind studied
here, reproducing the G-dwarf metallicity but this worsens the agreement with
other observational constraints.

</DOC>
<DOC>
<DOCNO> 85427 </DOCNO>
Thermal fluctuations of a quantized massive scalar field in Rindler


  Thermal fluctuations for a massive scalar field in the Rindler wedge are
obtained by applying the point-splitting procedure to the zero temperature
Feynman propagator in a conical spacetime. Renormalization is implemented by
removing the zero temperature contribution. It is shown that for a field of non
vanishing mass the thermal fluctuations, when expressed in terms of the local
temperature, do not have Minkowski form. As a by product, Minkowski vacuum
fluctuations seen by an uniformly accelerated observer are determined and
confronted with the literature.

</DOC>
<DOC>
<DOCNO> 71429 </DOCNO>
Bounds in proton-proton elastic scattering at low momentum transfer


  We present a bound on the imaginary part of the single helicity-flip
amplitude for spin 1/2-spin 1/2 scattering at small momentum transfer. The
variational method of Lagrange multipliers is employed to optimize the
single-flip amplitude using the values of the total cross section, the elastic
cross section and diffraction slope as equality constraints in addition to the
inequality constraints resulting from unitarity. Such bounds provide important
information related to the determination of polarization of a proton beam. In
the case of elastic proton collisions the analyzing power at small scattering
angles inside the Coulomb Nuclear Interference region offers a method of
measuring the polarization of a proton beam, the accuracy of the polarization
measurement depending on the single helicity-flip amplitude. The bound obtained
on the imaginary part of the single helicity-flip amplitude indicates that the
analyzing power for proton-proton collisions in the Coulomb nuclear
interference region should take positive nonzero values at high energies.

</DOC>
<DOC>
<DOCNO> 170123 </DOCNO>
Entanglement molecules


  We investigate the entanglement properties of multiparticle systems,
concentrating on the case where the entanglement is robust against disposal of
particles. Two qubits -belonging to a multipartite system- are entangled in
this sense iff their reduced density matrix is entangled. We introduce a family
of multiqubit states, for which one can choose for any pair of qubits
independently whether they should be entangled or not as well as the relative
strength of the entanglement, thus providing the possibility to construct all
kinds of ''Entanglement molecules''. For some particular configurations, we
also give the maximal amount of entanglement achievable.

</DOC>
<DOC>
<DOCNO> 118585 </DOCNO>
Another Faint UV Object Associated with a Globular Cluster X-Ray Source:


  The core of the metal poor Galactic Globular Cluster M92 (NGC 6341) has been
observed with WFPC2 on the Hubble Space Telescope through visual, blue and
mid-UV filters in a program devoted to study the evolved stellar population in
a selected sample of Galactic Globular Clusters. In the UV $(m_{255},
m_{255}-U)$ color magnitude diagram we have discovered a faint `UV-dominant'
object. This star lies within the error box of a Low Luminosity Globular
Cluster X-ray source (LLGCX) recently found in the core of M92. The properties
of the UV star discovered in M92 are very similar to those of other UV stars
found in the core of some clusters (M13, 47 Tuc, M80, etc)---all of them are
brighter in the UV than in the visible and are located in the vicinity of a
LLGCX. We suggest that these stars are a new sub-class of cataclysmic
variables.

</DOC>
<DOC>
<DOCNO> 150628 </DOCNO>
p-Brane Black Holes as Stability Islands


  In multidimensional gravity with an arbitrary number of internal Ricci-flat
factor spaces, interacting with electric and magnetic $p$-branes, spherically
symmetric configurations are considered. It is shown that all single-brane
black-hole solutions are stable under spherically symmetric perturbations,
whereas similar solutions possessing naked singularities turn out to be
catastrophically unstable. The black hole stability conclusion is extended to
some classes of configurations with intersecting branes. These results do not
depend on the particular composition of the $D$-dimensional space-time, on the
number of dilatonic scalar fields $\phi^a$ and on the values of their coupling
constants. Some examples from 11-dimensional supergravity are considered.

</DOC>
<DOC>
<DOCNO> 67809 </DOCNO>
Non-perturbative scaling in the scalar theory


  A new approach to study the scaling behavior of the scalar theory near the
Gaussian fixed point in $d$-dimensions is presented. For a class of initial
data an explicit use of the Green's function of the evolution equation is made.
It is thus discussed under which conditions non-polynomial relevant
interactions can be generated by the renormalization group flow.

</DOC>
<DOC>
<DOCNO> 69701 </DOCNO>
Linearized Gravity about a Brane


  We use the Israel condition to treat carefully the weak-field perturbations
due to the presence of matter on a 3-brane embedded between two regions of
anti-de Sitter (AdS) space with different curvature lengths. A four dimensional
Newton's Law only emerges at distances that are large compared to the AdS
lengths. When a scalar curvature is included in the brane action, however, it
is possible to generate a four dimensional theory of gravity even when one or
both of the AdS lengths is large compared to distances along the brane. In
particular, we provide an example in which the AdS lengths can be larger than
the millimeter experimental bound.

</DOC>
<DOC>
<DOCNO> 70320 </DOCNO>
Kaluza-Klein Mediated Supersymmetry Breaking


  We discuss a framework for communicating supersymmetry breaking to the
visible sector where the radius modulus, which determines the size of extra
dimensions, has an auxiliary vacuum expectation value. The modulus couplings
generate mass splitting in Kaluza-Klein supermultiplets and they act as
messengers of supersymmetry breaking. The soft masses are expressed in terms of
renormalization-group functions and the sparticle spectrum is determined by
what kind of field propagates in the bulk. This framework also provides new
possibilities for solving the supersymmetric flavor problem.

</DOC>
<DOC>
<DOCNO> 11750 </DOCNO>
ZGB model with random distribution of inert sites


  A random distribution of inert sites is introduced in the Ziff-Gulari-Barshad
model to study the phase transitions between active and poisoned states. The
adsorption of ${\rm CO}$ and ${\rm O_2}$ molecules is not possible at the
position of the inert sites. This model is investigated in the site and pair
approximations, as well as through Monte Carlo simulations. We determine the
mean coverages of the elements as a function of the dilution and show that the
continuous transition between the active and O-poisoned state is slightly
affected by moderate values of dilution in the pair approximation and in the
simulations. On the other hand, from the analysis of the hysteresis curves, the
transition between the active and CO-poisoned states changes from first-order
to continuous as one increases the concentration of inactive sites. The
observed transition in the site and pair approximations is always of
first-order nature. We also found the lines of transition and spinodal points
as a function of the concentration of inert sites. Finally, the production rate
of ${\rm CO_2}$ is calculated as a function of the dilution of sites.

</DOC>
<DOC>
<DOCNO> 116324 </DOCNO>
On M Theory, Quantum Paradoxes and the New Relativity


  Recently a New Relativity Principle has been proposed by one of the authors
as the underlying physical and geometrical foundations of String and {\bf M}
Theory. It is explicitly shown that within the framework of the New Relativity
Theory, some Quantum Mechanical Paradoxes like the Einstein-Rosen Podolsky and
the Black Hole Information Loss, are easily resolved. Such New Relativity
Theory requires the introduction of an Infinite Dimensional Quantum Spacetime
as has been shown recently by one of us. This can be viewed as just another way
of looking at Feynman's path integral formulation of Quantum Mechanics. Instead
of having an infinite dimensional funcional integral over $all$ paths, smooth,
forwards and backwards in time, random and fractal, in a finite-dimensional
spacetime, one has a finite number of paths in an Infinite Dimensional Quantum
Spacetime. We present a few-lines proof why there is no such a thing as an {\bf
EPR} Paradox in this New Relativity theory. The reason is {\bf not} due to a
superluminal information speed but to a {\bf divergent} information charge
density. In the infinite dimensional limit, due to the properties of gamma
functions, the hypervolume enclosed by a $D$-dim hypersphere, of finite nonzero
radius, shrinks to zero : to a {\bf hyperpoint}, the infinite-dimensional
analog af a point. For this reason, Information flows through the
infinite-dimensional hypersurface of nonzero radius, but zero size, the
hyperpoint, in an instant. In this fashion we imbue an abstract mathematical
"point" with a true physical meaning : it is an entity in infinite dimensions
that has zero hypervolume at nonzero radius . A plausible resolution of the
Information Loss Paradox in Black Holes is proposed.

</DOC>
<DOC>
<DOCNO> 121935 </DOCNO>
Hydrodynamic Simulation of the Cosmological X-ray Background


  (Abridged) We use a hydrodynamic simulation of a LambdaCDM model to predict
the extragalactic X-ray background (XRB), focussing on emission from the
intergalactic medium (IGM). We also include X-rays from point sources
associated with galaxies in the simulation, and make maps of the angular
distribution of the emission. We find that filaments in the maps are not
evident, being diluted by projection. In the soft (0.5-2 keV) band, the mean
intensity of radiation from intergalactic and cluster gas is 2.3*10^-12
ergdeg^-2cm^-2s^-1, 35% of the total soft band emission. This is compatible at
the ~1 sigma level with estimates of the unresolved soft background from ROSAT
and {\it Chandra}. Only 4% of the hard (2-10 keV) emission is associated with
the IGM. Relative to AGN flux, the IGM component peaks at a lower redshift
(median z~0.45) so its clustering makes an important contribution to that of
the total XRB. The angular correlations on 0.1-10 arcmin scales are
significant, with an amplitude roughly consistent with an extrapolation of
recent ROSAT results to small scales. A cross-correlation of the XRB against
nearby galaxies taken from a simulated redshift survey also yields a strong
signal from the IGM. Although some recent papers have argued that the expected
soft band intensity from gas in galaxy, group, and cluster halos would exceed
XRB limits unless much of the gas is expelled by supernova feedback, we obtain
reasonable compatibility with current observations in a simulation that
incorporates cooling, star formation, and only modest feedback. A prediction of
our model is that the unresolved portion of the soft XRB will remain mostly
unresolved.

</DOC>
<DOC>
<DOCNO> 40628 </DOCNO>
Angular distribution of $J/\psi$ decays in dimuon channel in 800 GeV


  The anuglar distribution of $J/\psi$ decays in the $\mu^{+}\mu^{-}$ channel
in 800 proton-copper collisions has been measured for $x_F$ > 0.25. The
polarization parameter $\lambda$ is extracted in 1 GeV of $p_T$ and 0.1 of
$x_F$ bins for two magnet configugrations with different acceptances. The data
indicate that the $J/\psi$'s are produced with a slight transverse polarization
at small $x_F$, which turns to longitudinal at $x_F$ > 0.6. No $p_T$ dependence
of $\lambda$ is observed. Theoretical calculations are needed in order to
interpret the measurements.

</DOC>
<DOC>
<DOCNO> 117123 </DOCNO>
Electromagnetically induced absorption in magneto-optically trapped


  Electromagnetically induced absorption (EIA) was observed on a sample of $%
^{85}Rb$ in a magneto-optical trap using low intensity cw copropagating pump
and probe optical fields. At moderate trapping field intensity, the EIA
spectrum is determined by the Zeeman effect produced on the atomic ground-state
by the trapping quadrupolar magnetic field. The use of EIA spectroscopy for the
magnetic field mapping of cold atomic samples is illustrated.

</DOC>
<DOC>
<DOCNO> 7769 </DOCNO>
Raman Scattering from Magnetic Excitations in the Spin Ladder Compounds


  We present the Raman-scattering spectra of CaV2O5 and MgV2O5. The magnetic
contribution in the Raman spectra of CaV2O5 is found in the form of a strong
asymmetric line, centered at 2Delta, with a tail on the high-energy side. Our
analysis of its spectral shape shows that the magnetic ordering in CaV2O5 can
be described using a S=1/2 two-leg ladder Heisenberg antiferromagnetic model
with Jparallel/Jperp = 0.1, and a small interladder exchange. The spin gap and
exchange constant are estimated to be Delta = 400 cm-1 (570 K) and Jperp = 640
K. No magnon bound states are found. In contrast to CaV2O5 the existence of the
spin-gap is not confirmed in MgV2O5, since we found no feature in the spectra
which could be associated with the onset of the two-magnon continuum. Instead,
we observe two-magnon excitation at 340 cm-1, presumably related to the top of
the two-magnon brunch.

</DOC>
<DOC>
<DOCNO> 83210 </DOCNO>
Interaction in Quantum Communication Complexity


  One of the most intriguing facts about communication using quantum states is
that these states cannot be used to transmit more classical bits than the
number of qubits used, yet there are ways of conveying information with
exponentially fewer qubits than possible classically. Moreover, these methods
have a very simple structure---they involve little interaction between the
communicating parties. We look more closely at the ways in which information
encoded in quantum states may be manipulated, and consider the question as to
whether every classical protocol may be transformed to a ``simpler'' quantum
protocol of similar efficiency. By a simpler protocol, we mean a protocol that
uses fewer message exchanges. We show that for any constant k, there is a
problem such that its k+1 message classical communication complexity is
exponentially smaller than its k message quantum communication complexity, thus
answering the above question in the negative. Our result builds on two
primitives, local transitions in bi-partite states (based on previous work) and
average encoding which may be of significance in other applications as well.

</DOC>
<DOC>
<DOCNO> 101620 </DOCNO>
Rationality, quasirationality and finite W-algebras


  Some of the consequences that follow from the C_2 condition of Zhu are
analysed. In particular it is shown that every conformal field theory
satisfying the C_2 condition has only finitely many n-point functions, and this
result is used to prove a version of a conjecture of Nahm, namely that every
representation of such a conformal field theory is quasirational. We also show
that every such vertex operator algebra is a finite W-algebra, and we give a
direct proof of the convergence of its characters as well as the finiteness of
the fusion rules.

</DOC>
<DOC>
<DOCNO> 10354 </DOCNO>
The entrance dynamics of polymers into a gel


  We use computer simulations to study the (driven) dynamics of a charged
polymer in a disordered medium, thus mimicking the setting used in gel
electrophoresis. In agreement with experiments, we find that inside the gel the
mobility of the polymer is only a weak function of its length N. In contrast to
this, the mean entrance time into the gel, is a very strong function of N,
<tau_e > \propto N^1.3, and does not show any sign of saturation with
increasing N. We rationalize this effect by means of a simple model and propose
an experimental setup that should allow to increase the separation ability of
gel electrophoresis significantly.

</DOC>
<DOC>
<DOCNO> 8375 </DOCNO>
Second Topological Moment < m^2 > of Two Closed Entangled Polymers


  We calculate the second topological moment < m^2 > of entanglement of two
closed polymers $P_1$ and $P_2$ in a solution. The result holds approximately
for a closed polymer linked to many others, which may be considered as a single
very long effective polymer.

</DOC>
<DOC>
<DOCNO> 68082 </DOCNO>
Probing possible decoherence effects in atmospheric neutrino


  It is shown that the results of the Super-Kamiokande atmospheric neutrino
experiment, interpreted in terms of nu_mu<--->nu_tau flavor transitions, can
probe possible decoherence effects induced by new physics (e.g., by quantum
gravity) with high sensitivity, supplementing current laboratory tests based on
kaon oscillations and on neutron interferometry. By varying the (unknown)
energy dependence of such effects, one can either obtain strong limits on their
amplitude, or use them to find an unconventional solution to the atmospheric nu
anomaly based solely on decoherence.

</DOC>
<DOC>
<DOCNO> 12855 </DOCNO>
Free energy of the Fr\"ohlich polaron in two and three dimensions


  We present a novel Path Integral Monte Carlo scheme to solve the Fr\"ohlich
polaron model. At intermediate and strong electron-phonon coupling, the polaron
self-trapping is properly taken into account at the level of an effective
action obtained by a preaveraging procedure with a retarded trial action. We
compute the free energy at several couplings and temperatures in three and two
dimensions. Our results show that the accuracy of the Feynman variational upper
bound for the free energy is always better than 5% although the thermodynamics
derived from it is not correct. Our estimates of the ground state energies
demonstrate that the second cumulant correction to the variational upper bound
predicts the self energy to better than 1% at intermediate and strong coupling.

</DOC>
<DOC>
<DOCNO> 120387 </DOCNO>
Light Curve and Spectral Models for the Hypernova SN 1998bw associated


  A refined model for the unusual Type Ic supernova 1998bw, discovered as the
optical counterpart of GRB980425, is presented, and synthetic light curves and
spectra are compared with the observations. The first 30 days of the light
curve and the broad line features of the spectra can be reproduced with the
hydrodynamical model of the explosion of a 14$M_\odot$ C+O star, the core of a
star with initial mass 40$M_\odot$, assuming that the explosion was very
energetic (kinetic energy $E_{\rm K} = 5 \times 10^{52}$ erg) and that
0.4$M_\odot$ of $^{56}$Ni were synthesized. At late times, however, the
observed light curve tail declines more slowly than this energetic model, and
is in better agreement with a less energetic ($E_{\rm K} = 7 \times 10^{51}$
erg) one. This shift to a less energetic model may imply that the inner part of
the ejecta has higher density and lower velocities than the spherically
symmetric model with $E_{\rm K} = 5 \times 10^{52}$ erg, so that $\gamma$-rays
deposit more efficiently. We suggest that an aspherical explosion can produce
such a structure of the ejecta. We also study detailed nucleosynthesis
calculations for hyper-energetic supernova explosions and compare the yields
with those of normal supernovae.

</DOC>
<DOC>
<DOCNO> 12596 </DOCNO>
Optical manipulation of nuclear spin by a two-dimensional electron gas


  Conduction electrons are used to optically polarize, detect and manipulate
nuclear spin in a (110) GaAs quantum well. Using optical Larmor magnetometry,
we find that nuclear spin can be polarized along or against the applied
magnetic field, depending on field polarity and tilting of the sample with
respect to the optical pump beam. Periodic optical excitation of the
quantum-confined electron spin reveals a complete spectrum of optically-induced
and quadrupolar-split nuclear resonances, as well as evidence for delta m = 2
transitions.

</DOC>
<DOC>
<DOCNO> 10163 </DOCNO>
Retarded versus time-nonlocal quantum kinetic equations


  The finite duration of the collisions in Fermionic systems as expressed by
the retardation time in non-Markovian Levinson-type kinetic equations is
discussed in the quasiclassical limit. We separate individual contributions
included in the memory effect resulting in (i) off-shell tails of the Wigner
distribution, (ii) renormalization of scattering rates and (iii) of the
single-particle energy, (iv) collision delay and (v) related non-local
corrections to the scattering integral. In this way we transform the Levinson
equation into the Landau-Silin equation extended by the non-local corrections
known from the theory of dense gases. The derived nonlocal kinetic equation
unifies the Landau theory of quasiparticle transport with the classical kinetic
theory of dense gases. The space-time symmetry is discussed versus
particle-hole symmetry and a solution is proposed which transforms these two
exclusive pictures into each other.

</DOC>
<DOC>
<DOCNO> 118640 </DOCNO>
Old models for Cygnus X-1 and AGN


  Recently, there appeared many papers devoted to the modeling of X-ray
properties of Cygnus X-1 and other black hole accretion disk candidates: e.g.
J.Poutanen, J.Krolik, F.Ryde, MNRAS 292 (1997) L21; E.Agol, J.Krolik, ApJ 507
(1998) 304; A.Beloborodov, in ``High Energy Processes in Accreting Black
Holes'', ASP Conf. Series, 161, (1999), p.295. The goal of this electronic
publication is to draw attention to our old papers where many ideas of recent
discussions were anticipated (hot coronae, Comptonization, photon damping of
waves, particle acceleration and matter ejection from accretion disks with
large scale poloidal magnetic fields, etc.)

</DOC>
<DOC>
<DOCNO> 71300 </DOCNO>
Low x Physics


  This is a talk, given at Diffraction'2000, Sept. 2 - 7, Centraro, Italy. In
this talk, we present the arguments, that a new QCD regime - gluon saturation,
has been reached at HERA.

</DOC>
<DOC>
<DOCNO> 118046 </DOCNO>
Modification of AGB wind in a binary system


  We explore one of plausible causes of asymmetry in the wind of an AGB star -
the presence of a binary companion. We have developed a simple method for
estimating the intrinsic non-sphericity of the outflow in that case. Assuming
the Roche model, local stellar parameters (T_eff, g) are calculated, and then a
formula for the local mass loss rate is applied. As a by-product a relation
between the ratio of stellar radius to the Roche lobe radius and the overall
wind enhancement is obtained.

</DOC>
<DOC>
<DOCNO> 150430 </DOCNO>
Absorption Cross Section of Scalar Field in Supergravity Background


  It has recently been shown that the equation of motion of a massless scalar
field in the background of some specific p branes can be reduced to a modified
Mathieu equation. In the following the absorption rate of the scalar by a D3
brane in ten dimensions is calculated in terms of modified Mathieu functions of
the first kind, using standard Mathieu coefficients. The relation of the latter
to Dougall coefficients (used by others) is investigated. The S-matrix obtained
in terms of modified Mathieu functions of the first kind is easily evaluated if
known rapidly convergent low energy expansions of these in terms of products of
Bessel functions are used. Leading order terms, including the interesting
logarithmic contributions, can be obtained analytically.

</DOC>
<DOC>
<DOCNO> 101525 </DOCNO>
Minimizing area among Lagrangian surfaces: the mapping problem


  This paper introduces a geometrically constrained variational problem for the
area functional. We consider the area restricted to the langrangian surfaces of
a Kaehler surface, or, more generally, a symplectic 4-manifold with suitable
metric, and study its critical points and in particular its minimizers. We
apply this study to the problem of finding canonical representatives of the
lagrangian homology (that part of the homology generated by lagrangian cycles).

</DOC>
<DOC>
<DOCNO> 100013 </DOCNO>
Double Bubbles Minimize


  The classical isoperimetric inequality in R^3 states that the surface of
smallest area enclosing a given volume is a sphere. We show that the least area
surface enclosing two equal volumes is a double bubble, a surface made of two
pieces of round spheres separated by a flat disk, meeting along a single circle
at an angle of 120 degrees.

</DOC>
<DOC>
<DOCNO> 170625 </DOCNO>
Ptolemyness of conventional program for microcosm investigations and


  It is shown that the conventional approach to microcosm investigations uses
an incorrect supposition (incorrect space-time model) whose incorrectness is
compensated by means of additional hypotheses, known as quantum mechanics
principles. Such a conception reminds the Ptolemaic doctrine of celestial
mechanics. Alternative research program, which uses a more correct space-time
model and does not need additional hypotheses (quantum principles) for free
explanations of quantum effects, is suggested. If the more correct space-time
model were known in the beginning of XXth century, when research of microcosm
started, quantum mechanics could develop in other way. The alternative research
program appeared with a secular delay, because all this time the necessary
mathematical technique was not available for researchers. Absence of necessary
mathematical technique is connected with some prejudices which have been
overcame at the construction of new conception of geometry and that of
statistical description. Basic statements of the new mathematical technique and
principles of its application in alternative research program are presented in
the paper.

</DOC>
<DOC>
<DOCNO> 119972 </DOCNO>
150 keV Emission from PKS2149-306 with BeppoSAX


  A BeppoSAX observation of the z=2.34 quasar PKS2149-306 produced a strong
signal in the high energy PDS instrument up to a maximum observed energy of
nearly 50 keV, 150 keV in the quasar frame. The Beppo-SAX spectrum spans almost
3 decades (0.3-150 keV, quasar frame) and shows an extremely hard
(alpha=0.4+/-0.05) X-ray spectrum above 3 keV (comparable to the X-ray
background slope), and either a softer (alpha=1.0(+0.6, -0.3)) low energy
component, or an ionized absorber at zero redshift. No evidence is seen of an
Fe-K emission line (EW<167 eV at 6.5 keV quasar frame) or a Compton hump
(R<0.3). A bremsstrahlung fit gives kT(rest)=46(+32, -16) keV, similar to the
X-ray background value, and a high energy cut-off power law requires E(cut)>120
keV (quasar frame).
    The SED of PKS 2149-306 shows two peaks at ~ 10(12+/-0.5}Hz and
\~10(21+/-1.0)Hz (~ 0.3 mm and ~ 4 MeV), strongly resembling a low energy cutoff
BL~Lac object (LBL). The ratio of the two peaks shows an extreme Compton
dominance (C_D=1.4+/- 0.4), as in flat spectrum radio quasars (FSRQs). The
presence of an additional `optical/UV big bump' component may provide photons
that cool the jet, suppressing the radio emission.

</DOC>
<DOC>
<DOCNO> 119993 </DOCNO>
Near-infrared photometry of isolated spirals with and without an AGN.


  We present the analysis of morphological and photometric properties of a
sample of isolated spirals with (18) and without (11) an active nucleus, based
on near-infrared imaging in the J and K' bands. The aim of this analysis is to
find the differential properties that could be directly connected with the
phenomenon of nuclear activity. We stress the importance of using isolated
objects for that purpose. Our study shows that both sets of galaxies are
similar in their global properties: they define the same Kormendy relation,
their disk components share the same properties, the bulge and disk scale
lengths are correlated in a similar way, bar strengths and lengths are similar
for primary bars. Hosts of isolated Seyfert galaxies have bulge and disk
properties comparable to those of isolated non active spirals. Central colors
(the innermost 200 pc) of active galaxies are redder than the centers of non
active spirals, most probably due to AGN light being re-emitted by the hot dust
and/or due to circumnuclear star formation, through the contribution of
giants/supergiants. Only one of the Seyfert galaxies in our sample does not
present a primary bar,but both primary and secondary bars are equally present
in active and control objects. Secondary central elongations (associated with
secondary bars, lenses, rings or disks) may be somewhat different. Numerical
models indicate that such secondary bars are not strictly necessary to feed the
central engine when a primary bar is present. Our results show that down to
scales of 100-300 pc, there are no obvious differences between active and non
active spiral galaxies.

</DOC>
<DOC>
<DOCNO> 13167 </DOCNO>
Long-range effects in superconductor-ferromagnet structures


  We analyze the proximity effect in a superconductor/ferromagnet (S/F)
structure with a local inhomogeneity of the magnetization in the ferromagnet
near the S/F interface. We demonstrate that not only the singlet but also the
triplet component of the superconducting condensate is induced in the
ferromagnet due to the proximity effect. Although the singlet component of the
condensate penetrates into the ferromagnet over a short length $\xi
_{h}=\sqrt{D/h}$ ($h$ is the exchange field in the ferromagnet and $D$ the
diffusion coefficient), the triplet component, being of the order of the
singlet one at the S/F interface, penetrates over a long length
$\sqrt{D/\epsilon}$ ($\epsilon$ is the energy). This long-range penetration
into the ferromagnet leads to a significant increase of the ferromagnet
conductance below the superconducting critical temperature $T_{c}$.

</DOC>
<DOC>
<DOCNO> 101574 </DOCNO>
Cyclic homology of Hopf algebras


  A cyclic cohomology theory adapted to Hopf algebras has been introduced
recently by Connes and Moscovici. In this paper, we consider this object in the
homological framework, in the spirit of Loday-Quillen and Karoubi's work on the
cyclic homology of associative algebras. In the case of group algebras, we
interpret the decomposition of the classical cyclic homology of a group algebra
in terms of this homology. We also compute both cyclic homologies for truncated
quiver algebras.

</DOC>
<DOC>
<DOCNO> 83050 </DOCNO>
High-resolution path-integral development of financial options


  The Black-Scholes theory of option pricing has been considered for many years
as an important but very approximate zeroth-order description of actual market
behavior. We generalize the functional form of the diffusion of these systems
and also consider multi-factor models including stochastic volatility. Daily
Eurodollar futures prices and implied volatilities are fit to determine
exponents of functional behavior of diffusions using methods of global
optimization, Adaptive Simulated Annealing (ASA), to generate tight fits across
moving time windows of Eurodollar contracts. These short-time fitted
distributions are then developed into long-time distributions using a robust
non-Monte Carlo path-integral algorithm, PATHINT, to generate prices and
derivatives commonly used by option traders.

</DOC>
<DOC>
<DOCNO> 116573 </DOCNO>
Classical Electrodynamics


  Excerpts are presented from a graduate course on Classical Electrodynamics
held during the spring semester of 2000 at the Institute of Physics, Guanajuato
State University, Mexico

</DOC>
<DOC>
<DOCNO> 122260 </DOCNO>
The Luminosity Function of 81 Abell Clusters from the CRoNaRio


  We present the composite luminosity function (hereafter LF) of galaxies for
81 Abell clusters studied in our survey of the Northern Hemisphere, using DPOSS
data processed by the CRoNaRio collaboration. The derived LF is very accurate
due to the use of homogeneous data both for the clusters and the control fields
and to the local estimate of the background, which takes into account the
presence of large-scale structures and of foreground clusters and groups. The
global composite LF is quite flat down to $M^*+5$ has a slope
$\alpha\sim-1.0\pm0.2$ with minor variations from blue to red filters, and
$M^*\sim-21.8,-22.0,-22.3$ mag ($H_0=50$ km s$^{-1}$ Mpc$^{-1}$) in the $g, r$
and $i$ filters, respectively (errors are detailed in the text). We find a
significant difference between rich and poor clusters thus arguing in favour of
a dependence of the LF on the properties of the environment.

</DOC>
<DOC>
<DOCNO> 9902 </DOCNO>
Hydrodynamics beyond local equilibrium: application to electron gas


  Generalized hydrodynamic theory, which does not rest on the requirement of a
local equilibrium, is derived in the long-wave limit of a kinetic equation. The
theory bridges the whole frequency range between the quasistatic
(Navier-Stokes) hydrodynamics and the high frequency (Vlasov) collisionless
limit. In addition to pressure and velocity the theory includes new macroscopic
tensor variables. In a linear approximation these variables describe an
effective shear stress of a liquid and the generalized hydrodynamics recovers
the Maxwellian theory of highly viscous fluids - the media behaving as solids
on a short time scale, but as viscous fluids on long time intervals. It is
shown that the generalized hydrodynamics can be applied to the Landau theory of
Fermi liquid. Illustrative results for collective modes in confined systems are
given, which show that nonequilibrium effects qualitatively change the
collective dynamics in comparison with the predictions of the heuristic Bloch's
hydrodynamics. Earlier improvements of the Bloch theory are critically
reconsidered.

</DOC>
<DOC>
<DOCNO> 11225 </DOCNO>
On the origin of order from random two-body interactions


  We investigate the origin of order in the low-lying spectra of many-body
systems with random two-body interactions. Contrary to the common belief our
study based both on analytical as well as on numerical arguments shows that
these are the higher $J$-sectors whose ground states are more orderly than the
ones in the J=0-sector. A predominance of J=0 ground states turns out to be the
result of putting on together states with different characteristic energy
scales from different $J$-sectors.

</DOC>
<DOC>
<DOCNO> 150698 </DOCNO>
Some remarks on the free fields realization of the bosonic string on


  We discuss the classical solutions of the equations of motion and the
possible boundary condition for a bosonic string with Kalb-Ramond background in
AdS3. It turns out that there exists three different physical sectors and that
it is also possible to describe the motion on an extremal black hole
background. The existence of three sectors clearly shows how one of the spectra
proposed is incomplete. We consider also the classical 'canonical'
transformation which maps the string fields to the classical Wakimoto ones. It
turns however out that the Wakimoto fields are not free because of the boundary
conditions and in order to have the usual mode expansion with reasonable
behaviour under complex conjugation it is necessary to consider the
complexification of AdS3 and then add some constraints. Furthermore they cover
only half AdS3 and we need different patches to cover the whole space and to
make the above mentioned transformation really canonical.

</DOC>
<DOC>
<DOCNO> 68322 </DOCNO>
Q-ball formation in the gravity-mediated SUSY breaking scenario


  We study the formation of Q-balls which are made of flat directions that
appear in the supersymmetric extension of the standard model in the context of
gravity-mediated supersymmetry breaking. The full non-linear calculations for
the dynamics of the complex scalar field are made. Since the scalar potential
in this model is flatter than \phi^2, we have found that fluctuations develop
and go non-linear to form non-topological solitons, Q-balls. The size of a
Q-ball is determined by the most amplified mode, which is completely determined
by the model parameters. On the other hand, the charge of Q-balls depends
linearly on the initial charge density of the Affleck-Dine (AD) field. Almost
all the charges are absorbed into Q-balls, and only a tiny fraction of the
charges is carried by a relic AD field. It may lead to some constraints on the
baryogenesis and/or parameters in the particle theory. The peculiarity of
gravity-mediation is the moving Q-balls. This results in collisions between
Q-balls. It may increase the charge of Q-balls, and change its fate.

</DOC>
<DOC>
<DOCNO> 84113 </DOCNO>
A remark on Brans-Dicke dust cosmological solutions with negative


  Analysing the Brans-Dicke solutions for the dust phase, we show that, for
negative values of $\omega$, they contain scenarios that display an initial
subluminal expansion followed by an inflationary phase. We discuss these
solutions with respect to the results of the observation of high redshif
supernova as well as the age problem and structure formation. We stablish
possible connections of these solutions with those emerging from string
effective models.

</DOC>
<DOC>
<DOCNO> 10578 </DOCNO>
Phase diagram of an Ising model with long-range frustrating


  We present a theoretical study of the phase diagram of a frustrated Ising
model with nearest-neighbor ferromagnetic interactions and long-range
(Coulombic) antiferromagnetic interactions. For nonzero frustration, long-range
ferromagnetic order is forbidden, and the ground-state of the system consists
of phases characterized by periodically modulated structures. At finite
temperatures, the phase diagram is calculated within the mean-field
approximation. Below the transition line that separates the disordered and the
ordered phases, the frustration-temperature phase diagram displays an infinite
number of ``flowers'', each flower being made by an infinite number of
modulated phases generated by structure combination branching processes. The
specificities introduced by the long-range nature of the frustrating
interaction and the limitation of the mean-field approach are finally
discussed.

</DOC>
<DOC>
<DOCNO> 121307 </DOCNO>
An empirical model for protostellar collapse


  We propose a new analytic model for the initial conditions of protostellar
collapse in relatively isolated regions of star formation. The model is
non-magnetic, and is based on a Plummer-like radial density profile as its
initial condition. It fits: the observed density profiles of pre-stellar cores
and Class 0 protostars; recent observations in pre-stellar cores of roughly
constant contraction velocities over a wide range of radii; and the lifetimes
and accretion rates derived for Class 0 and Class I protostars. However, the
model is very simple, having in effect only 2 free parameters, and so should
provide a useful framework for interpreting observations of pre-stellar cores
and protostars, and for calculations of radiation transport and time-dependent
chemistry. As an example, we model the pre-stellar core L1544.

</DOC>
<DOC>
<DOCNO> 8026 </DOCNO>
Three-Dimensional Elastic Compatibility: Twinning in Martensites


  We show how the St.Venant compatibility relations for strain in three
dimensions lead to twinning for the cubic to tetragonal transition in
martensitic materials within a Ginzburg-Landau model in terms of the six
components of the symmetric strain tensor. The compatibility constraints
generate an anisotropic long-range interaction in the order parameter
(deviatoric strain) components. In contrast to two dimensions, the free energy
is characterized by a "landscape" of competing metastable states. We find a
variety of textures, which result from the elastic frustration due to the
effects of compatibility. Our results are also applicable to structural phase
transitions in improper ferroelastics such as ferroelectrics and
magnetoelastics, where strain acts as a secondary order parameter.

</DOC>
<DOC>
<DOCNO> 151240 </DOCNO>
$\tau$-function for analytic curves


  We review the concept of $\tau$-function for simple analytic curves. The
$\tau$-function gives a formal solution to the 2D inverse potential problem and
appears as the $\tau$-function of the integrable hierarchy which describes
conformal maps of simply-connected domains bounded by analytic curves to the
unit disk. The $\tau$-function also emerges in the context of topological
gravity and enjoys an interpretation as a large $N$ limit of the normal matrix
model.

</DOC>
<DOC>
<DOCNO> 121401 </DOCNO>
Velocity Gradients in the Intracluster Gas of the Perseus Cluster


  We report the results of spatially resolved X-ray spectroscopy of 8 different
ASCA pointings distributed symmetrically around the center of the Perseus
cluster. The outer region of the intracluster gas is roughly isothermal, with
temperature ~ 6-7 keV, and metal abundance ~ 0.3 Solar. Spectral analysis of
the central pointing is consistent with the presence of a cooling flow and a
central metal abundance gradient.
 A significant velocity gradient is found along an axis at a position angle of
\~135 deg, which is ~ 45 deg discrepant with the major axis of the X-ray
elongation. The radial velocity difference is found to be greater than 1000
km/s/Mpc at the 90% confidence level. Simultaneous fittings of GIS 2 & 3
indicate that the velocity gradient is significant at the 95% confidence level
and the F-test rules out constant velocities at the 99% level. Intrinsic short
and long term variations of gain are unlikely (P < 0.03) to explain the
velocity discrepancies.

</DOC>
<DOC>
<DOCNO> 8582 </DOCNO>
Phase behaviour of a model of colloidal particles with a fluctuating


  Colloidal particles are not simple rigid particles, in general an isolated
particle is a system with many degrees of freedom in its own right, e.g., the
counterions around a charged colloidal particle.The behaviour of model
colloidal particles, with a simple phenomenological model to account for these
degrees of freedom, is studied. It is found that the interaction between the
particles is not pairwise additive. It is even possible that the interaction
between a triplet of particles is attractive while the pair interaction is
repulsive. When this is so the liquid phase is either stable only in a small
region of the phase diagram or absent altogether.

</DOC>
<DOC>
<DOCNO> 170254 </DOCNO>
Finite resolution of time in continuous measurements: phenomenology and


  Definition of a quantum corridor describing monitoring a quantum observable
in the framework of the phenomenological restricted-path-integral (RPI)
approach is generalized for the case of a finite resolution of time. The
resulting evolution of the continuously measured system cannot be presented by
a differential equation. Monitoring of the position of a quantum particle is
also considered with the help of a model which takes into account a finite
resolution of time. The results based on the model are shown to coincide with
those of the phenomenological approach.

</DOC>
<DOC>
<DOCNO> 117301 </DOCNO>
Atomic Radiative Transitions in Thermo Field Dynamics


  In this work we study the energy exchange between an atomic system and a
thermal radiation field, using the Dalibard, Dupont-Roc and Cohen-Tannoudji
(DDC) construct, incorporating temperature effects to the eigenstates of the
radiation field operator through the electromagnetic propagator of Thermo Field
Dynamics in the Coulomb gauge. We also discuss the stability of the atomic
system at finite temperature.

</DOC>
<DOC>
<DOCNO> 178886 </DOCNO>
Hadronic Decays of N and \Delta Resonances in a Chiral Quark Model


  \pi and \eta decay modes of light baryon resonances are investigated within a
chiral quark model whose hyperfine interaction is based on Goldstone-boson
exchange. For the decay mechanism a modified version of the 3P0 model is
employed. Our primary aim is to provide a further test of the recently proposed
Goldstone-boson-exchange constituent quark model. We compare the predictions
for \pi and \eta decay widths with experiment and also with results from a
traditional one-gluon-exchange constituent quark model. The differences between
nonrelativistic and semirelativistic versions of the constituent quark models
are outlined. We also discuss the sensitivity of the results on the
parametrization of the meson wave function entering the 3P0 model.

</DOC>
<DOC>
<DOCNO> 69561 </DOCNO>
The anapole form factor of the nucleon


  The anapole form factor of the nucleon is calculated in chiral perturbation
theory in leading order. To this order, the form factor originates from the
pion cloud, and is proportional to the non-derivative parity-violating
pion-nucleon coupling. The momentum dependence of the form factor - and in
particular, its radius - is completely determined by the pion mass.

</DOC>
<DOC>
<DOCNO> 117970 </DOCNO>
Polaris: astrometric orbit, position, and proper motion


  We derive the astrometric orbit of the photo-center of the close pair alpha
UMi AP (=alpha UMi Aa) of the Polaris multiple stellar system. The orbit is
based on the spectroscopic orbit of the Cepheid alpha UMi A (orbital period of
AP: 29.59 years), and on the difference Delta mu between the
quasi-instantaneously measured HIPPARCOS proper motion of Polaris and the
long-term-averaged proper motion given by the FK5. There remains an ambiguity
in the inclination i of the orbit, since Delta mu cannot distinguish between a
prograde orbit (i=50.1 deg) and a retrograde one (i=130.2 deg). Available
photographic observations of Polaris favour strongly the retrograde orbit. For
the semi-major axis of the photo-center of AP we find about 29 milliarcsec
(mas). For the component P, we estimate a mass of 1.5 solar masses and a
magnitude difference with respect to the Cepheid of 6.5 mag. The present
separation between A and P should be about 160 mas. We obtain the proper motion
of the center-of-mass of alpha UMi AP with a mean error of about 0.45 mas/year.
Using the derived astrometric orbit, we find the position of the center-of-mass
at the epoch 1991.31 with an accuracy of about 3.0 mas. Our ephemerides for the
orbital correction, required for going from the position of the center-of-mass
to the instantaneous position of the photo-center of AP at an arbitrary epoch,
have a typical uncertainty of 5 mas. For epochs which differ from the HIPPARCOS
epoch by more than a few years, a prediction for the actual position of Polaris
based on our results should be significantly more accurate than using the
HIPPARCOS data in a linear prediction, since the HIPPARCOS proper motion
contains the instantaneous orbital motion of about 4.9 mas/year = 3.1 km/s.
Finally we derive the galactic space motion of Polaris.

</DOC>
<DOC>
<DOCNO> 122521 </DOCNO>
Spin Profile of Galactic Halos and Disk Formation


  We summarize recent developments in the study of the origin of halo spin
profiles and preliminary implications on disk formation. The specific
angular-momentum distributions within halos in N-body simulations match a
universal shape, M(<j) \propto j/(j_0+j). It is characterized by a power law
over most of the mass, and one shape parameter in addition to the spin
parameter \lambda. The angular momentum tends to be aligned throughout the halo
and of cylindrical symmetry. Even if angular momentum is conserved during
baryonic infall, the resultant disk density profile is predicted to deviate
from exponential, with a denser core and an extended tail. A slightly corrected
version of the scaling relation due to linear tidal-torque theory is used to
explain the origin of a typical power-law profile in shells, j(M) \propto M^s
with s \gsim 1. While linear theory crudely predicts the amplitudes of halo
spins, it is not a good predictor of their directions. Independently, mergers
of halos are found to produce a similar profile due to j transfer from the
orbit to the product halo via dynamical friction and tidal stripping. The halo
spin is correlated with having a recent major merger, though this correlation
is weakened by mass loss. These two effects are due to a correlation between
the spins of neighboring halos and their orbit, leading to prograde mergers.

</DOC>
<DOC>
<DOCNO> 101760 </DOCNO>
Canonical formulation treatment of a free relativistic spinning particle


  The canonical method of constrained system is discussed. The equations of
motion for a free relativistic spinning particle are obtained without using
gauge fixing conditions. The quantization of this model is discussed.

</DOC>
<DOC>
<DOCNO> 99347 </DOCNO>
Uniqueness theorems for inverse obstacle scattering in Lipschitz domains


  An inverse problem of finding an obstacle and the boundary condition on its
surface from the fixed-energy scattering data is studied. A new method is
developed for a proof of the uniqueness results. The method does not use the
discreteness of the spectrum of the corresponding Laplacian in a bounded
domain. Proof of the uniqueness results is based on the fact that the Hilbert
space of square integrable functions is separable.

</DOC>
<DOC>
<DOCNO> 99679 </DOCNO>
Z_2-systolic-freedom


  We give the first example of systolic freedom over torsion coefficients. The
phenomenon is a bit unexpected (contrary to a conjecture of Gromov's) and more
delicate than systolic freedom over the integers.

</DOC>
<DOC>
<DOCNO> 170259 </DOCNO>
Property Attribution and the Projection Postulate in Relativistic


  State-vectors resulting from collapse along the forward light cone from a
measurement interaction can be used for the attribution of both local and
non-local properties.

</DOC>
<DOC>
<DOCNO> 84633 </DOCNO>
The interaction force between rotating black holes at equilibrium


  We study the previously constructed Riemann problem whose solutions
correspond to equilibrium configurations of black holes. We evaluate the metric
coefficients at the symmetry axis and the interaction force between the black
holes.

</DOC>
<DOC>
<DOCNO> 101040 </DOCNO>
Vertex Algebras and Algebraic Curves


  This is the text of the Bourbaki seminar that I gave on June 24, 2000.

</DOC>
<DOC>
<DOCNO> 178423 </DOCNO>
Realistic Ghost State : Pauli Forbidden State from Rigorous Solution of


  The antisymmetrization of the composite particles in cluster model
calculations manifests itself in Pauli forbidden states (ghost states), if one
restricts oneself on undeformed cluster in the low energy region. The
resonating group method and the generating coordinate method rely on a property
of the norm kernel, which introduces some of the ghost states. The norm kernel
has been usually calculated under the assumption that the inner wavefunctions
have a simple Gaussian form. It is the first time that this assumption is
tested by the rigorous way. In the 4He+N system, we demonstrate a ghost state,
which is calculated from a rigorous solution of Yakubovsky equations for the
alpha particle. The ghost states calculated by rigorous and approximate methods
turn out to have a very similar form. It is analytically proved that the trace
of the norm kernel does not depend on the inner wavefunction we choose.

</DOC>
<DOC>
<DOCNO> 69949 </DOCNO>
Absorption of Electro-magnetic Waves in a Magnetized Medium


  In continuation to our earlier work, in which the structure of the vacuum
polarisation tensor in a medium was analysed in presence of a background
electro-magnetic field, we discuss the absorptive part of the vacuum
polarization tensor. Using the real time formalism of finite temperature field
theory we calculate the absorptive part of 1-loop vacuum polarisation tensor in
the weak field limit ($eB < m^2$). Estimates of the absorption probability are
also made for different physical conditions of the background medium.

</DOC>
<DOC>
<DOCNO> 102352 </DOCNO>
Orbit reduction of exterior differential systems, and group-invariant


  For For a given PDE system, or an exterior differential system possessing a
Lie group of internal symmetries the orbit reduction procedure is introduced.
It is proved that the solutions of the reduced exterior differential system are
in one-to-one correspondence with the moduli space of regular solutions of the
prolongation of the original system.
  The isomorphism between the local characteristic cohomology of the reduced
unconstrained jet space and the Lie algebra cohomology of the symmetry group is
established.
 The group-invariant Euler-Lagrange equations of an invariant variational
problem are described as a composition of the Euler-Lagrange operators on the
reduced jet space and certain other differential operators on the reduced jet
space. The practical algorithm of computing these operators is given.

</DOC>
<DOC>
<DOCNO> 40420 </DOCNO>
Measurement of the B0 Lifetime and Oscillation Frequency using


  The lifetime and oscillation frequency of the B0 meson has been measured
using B0->D*+l-v decays recorded on the Z0 peak with the OPAL detector at LEP.
The D*+ -> D0pi+ decays were reconstructed using an inclusive technique and the
production flavour of the B0 mesons was determined using a combination of tags
from the rest of the event. The results t_B0 = 1.541 +- 0.028 +- 0.023 ps, Dm_d
= 0.497 +- 0.024 +- 0.025 ps-1 were obtained, where in each case the first
error is statistical and the second systematic.

</DOC>
<DOC>
<DOCNO> 169775 </DOCNO>
Strict Holism in a Quantum Superposition of Macroscopic States


  We show that some N-particle quantum systems are holistic, such that the
system is deterministic, whereas its parts are random. The total correlation is
not sufficient to determine the probability distribution, showing a need for
extra measurements. We propose a formal definition of holism not based on
separability.

</DOC>
<DOC>
<DOCNO> 83087 </DOCNO>
On The Closest String and Substring Problems


  The problem of finding a center string that is `close' to every given string
arises and has many applications in computational biology and coding theory.
This problem has two versions: the Closest String problem and the Closest
Substring problem. Assume that we are given a set of strings ${\cal S}=\{s_1,
s_2, ..., s_n\}$ of strings, say, each of length $m$. The Closest String
problem asks for the smallest $d$ and a string $s$ of length $m$ which is
within Hamming distance $d$ to each $s_i\in {\cal S}$. This problem comes from
coding theory when we are looking for a code not too far away from a given set
of codes. The problem is NP-hard. Berman et al give a polynomial time algorithm
for constant $d$. For super-logarithmic $d$, Ben-Dor et al give an efficient
approximation algorithm using linear program relaxation technique. The best
polynomial time approximation has ratio 4/3 for all $d$ given by Lanctot et al
and Gasieniec et al. The Closest Substring problem looks for a string $t$ which
is within Hamming distance $d$ away from a substring of each $s_i$. This
problem only has a $2- \frac{2}{2|\Sigma|+1}$ approximation algorithm
previously Lanctot et al and is much more elusive than the Closest String
problem, but it has many applications in finding conserved regions, genetic
drug target identification, and genetic probes in molecular biology. Whether
there are efficient approximation algorithms for both problems are major open
questions in this area. We present two polynomial time approxmation algorithms
with approximation ratio $1+ \epsilon$ for any small $\epsilon$ to settle both
questions.

</DOC>
<DOC>
<DOCNO> 102747 </DOCNO>
Operator formalism of quantum mechanics


  This is the first chapter of a new and unconventional textbook on quantum
mechanics and quantum field theory. The chapter introduces standard quantum
mechanics by means of a symmetry principle, without reference to classical
mechanics. The mathematical foundation of this approach comes from a recent
paper of Naudts and Kuna on covariance systems. The standard representation of
quantum mechanics is derived. Next, spin and mass of a quantum particle are
explained as labels of projective representations of the Galilei group.

</DOC>
<DOC>
<DOCNO> 100781 </DOCNO>
Gauge techniques in time and frequency domain TLM


  Typical features of the Transmission Line Matrix (TLM) algorithm in
connection with stub loading techniques and prone to be hidden in common
frequency domain formulations are elucidated within the propagator approach to
TLM. In particular, the latter reflects properly the perturbative character of
the TLM scheme and its relation to gauge field models. Internal 'gauge' degrees
of freedom are made explicit in the frequency domain by introducing the complex
nodal S-matrix as a function of operators that act on external or internal
fields or virtually couple the two. As a main benefit, many techniques and
results gained in the time domain thus generalize straight away. The recently
developed deflection method for algorithm synthesis, which is extended in this
paper, ort the non-orthogonal node approximating Maxwell's equations, for
instance, become at once available in the frequency domain. In view of
applications in computational plasma physics, the TLM model of a relativistic
charged particle current coupled to the Maxwell field is treated as a
prototype.
  Keywords: Gauge techniques, parturbative schemes, TLM method, propagator
approach, plasma physics

</DOC>
<DOC>
<DOCNO> 13715 </DOCNO>
Non-linear feedback effects in coupled Boson-Fermion systems


  We address ourselves to a class of systems composed of two coupled subsystems
without any intra-subsystem interaction: itinerant Fermions and localized
Bosons on a lattice. Switching on an interaction between the two subsystems
leads to feedback effects which result in a rich dynamical structure in both of
them. Such feedback features are studied on the basis of the flow equation
technique - an infinite series of infinitesimal unitary transformations - which
leads to a gradual elimination of the inter-subsystem interaction. As a result
the two subsystems get decoupled but their renormalized kinetic energies become
mutually dependent on each other. Choosing for the inter - subsystem
interaction a charge exchange term (the Boson-Fermion model) the initially
localized Bosons acquire itinerancy through their dependence on the
renormalized Fermion dispersion. This latter evolves from a free particle
dispersion into one showing a pseudogap structure near the chemical potential.
Upon lowering the temperature both subsystems simultaneously enter a
macroscopic coherent quantum state. The Bosons become superfluid, exhibiting a
soundwave like dispersion while the Fermions develop a true gap in their
dispersion. The essential physical features described by this technique are
already contained in the renormalization of the kinetic terms in the respective
Hamiltonians of the two subsystems. The extra interaction terms resulting in
the process of iteration only strengthen this physics. We compare the results
with previous calculations based on selfconsistent perturbative approaches.

</DOC>
<DOC>
<DOCNO> 150766 </DOCNO>
Black hole formation in bidimensional dilaton gravity coupled to scalar


  This work deals with the formation of black hole in bidimensional dilaton
gravity coupled to scalar matter fields. We investigate two scalar matter
systems, one described by a sixth power potential and the other defined with
two scalar fields containing up to the fourth power in the fields. The
topological solutions that appear in these cases allow the formation of black
holes in the corresponding dilaton gravity models.

</DOC>
<DOC>
<DOCNO> 68032 </DOCNO>
Noncompact chiral U(1) gauge theories on the lattice


  A new, adiabatic phase choice is adopted for the overlap in the case of an
infinite volume, noncompact abelian chiral gauge theory. This gauge choice
obeys the same symmetries as the Brillouin-Wigner (BW) phase choice, and, in
addition, produces a Wess-Zumino functional that is linear in the gauge
variables on the lattice. As a result, there are no gauge violations on the
trivial orbit in all theories, consistent and covariant anomalies are simply
related and Berry's curvature now appears as a Schwinger term. The adiabatic
phase choice can be further improved to produce a perfect phase choice, with a
lattice Wess-Zumino functional that is just as simple as the one in continuum.
When perturbative anomalies cancel, gauge invariance in the fermionic sector is
fully restored. The lattice effective action describing an anomalous abelian
gauge theory has an explicit form, close to one analyzed in the past in a
perturbative continuum framework.

</DOC>
<DOC>
<DOCNO> 119344 </DOCNO>
BeppoSAX Observations of Bright Radio Galaxies


  BeppoSAX observations of Broad Line Radio Galaxies (BLRGs) have shown that
they have a considerable variety of spectral properties and important
differences with respect to their radio-quiet counter-part Seyfert 1s. In radio
galaxies the soft photons are often absorbed by cold material. In contrast, in
Seyfert 1s the soft photons are generally absorbed by warm gas. The iron lines,
always detected in Seyfert 1s, are not always present in BLRGs and generally
are weak. In addition, small iron line equivalent widths seem to correspond to
weak reflection components in radio galaxies.
  The emerging picture of BLRGs is complex. Probably several X-ray components,
jet, accretion flow and molecular torus, mixed in different way in different
objects, contribute to the production of their X-ray spectrum and determine the
observed variety. The weakness of the reprocessed features can be explained
either by a dilution of the Seyfert-like continuum from non-thermal (jet)
radiation or by an accretion gas that is hot and geometrically thick close to
the black hole and cold geometrically thin (i.e. able to reprocess the primary
X-ray radiation) at larger radii.

</DOC>
<DOC>
<DOCNO> 71169 </DOCNO>
Functional Integral Method in the Theory of Color Superconductivity


  We propose to study the superconducting pairing of quarks with the formation
of the diquarks as well as the quark-antiquark pairing in QCD by means of the
functional integral technique. The dynamical equations for the superconducting
order parameters are the nonlinear integral equations for the composite quantum
fields describing the quark-quark or quark-antiquark systems. These composite
fields are the bi-local fields if the pairing is generated by the gluon
exchange while for the instanton induced pairing interactions they are the
local ones. The expressions of the free energy densities are derived. The
binding of three quarks is also discussed.

</DOC>
<DOC>
<DOCNO> 10290 </DOCNO>
Liouville Integrability of Classical Calogero-Moser Models


  Liouville integrability of classical Calogero-Moser models is proved for
models based on any root systems, including the non-crystallographic ones. It
applies to all types of elliptic potentials, i.e. untwisted and twisted
together with their degenerations (hyperbolic, trigonometric and rational),
except for the rational potential models confined by a harmonic force.

</DOC>
<DOC>
<DOCNO> 13623 </DOCNO>
Bell's Theorem and Locality in Space


  Bell's theorem states that some quantum correlations can not be represented
by classical correlations of separated random variables. It has been
interpreted as incompatibility of the requirement of locality with quantum
mechanics. We point out that in fact the space part of the wave function was
neglected in the proof of Bell's theorem. However this space part is crucial
for considerations of property of locality of quantum system. Actually the
space part leads to an extra factor in quantum correlations and as a result the
ordinary proof of Bell's theorem fails in this case. We present a criterium of
locality in a realist theory of hidden variables. It is argued that predictions
of quantum mechanics for Gaussian wave functions can be consistent with Bell's
inequalities and hence Einstein's local realism is restored in this case.

</DOC>
<DOC>
<DOCNO> 178602 </DOCNO>
Phi decay in nuclei


  We have studied the decay of the \phi meson in nuclear matter by taking into
account the renormalization of the K and \bar{K} mesons in the medium. We
separate the contribution of the total width into different reaction channels,
K\bar{K} and KYh, the latter ones associated with the \phi N \to K^+ Y
reactions. We find a total width at normal nuclear matter density of about 22
MeV, considerably larger than the free one.

</DOC>
<DOC>
<DOCNO> 8964 </DOCNO>
Distribution of consecutive waves in the sandpile model on the


  The scaling properties of waves of topplings in the sandpile model on the
Sierpinski gasket are investigated. The exponent describing the asymptotics of
the distribution of last waves in an avalanche is found. Predictions for
scaling exponents in the forward and backward conditional probabilites for two
consecutive waves are given. All predictions were examined by numerical
simulations and were found to be in reasonable agreement with the obtained
data.

</DOC>
<DOC>
<DOCNO> 100701 </DOCNO>
Functionals depending on curvatures with constraints


  We deal with a family of functionals depending on curvatures and we prove for
them compactness and semicontinuity properties in the class of closed and
bounded sets which satisfy a uniform exterior and interior sphere condition. We
apply the results to state an existence theorem for the Nitzberg and Mumford
problem under this additional constraint.

</DOC>
<DOC>
<DOCNO> 120856 </DOCNO>
Evolution of Galaxy morphologies in Clusters


  We have studied the evolution of galaxian morphologies from ground-based,
good-seeing images of 9 clusters at z=0.09-0.25. The comparison of our data
with those relative to higher redshift clusters (Dressler et al. 1997) allowed
us to trace for the first time the evolution of the morphological mix at a
look-back time of 2-4 Gyr, finding a dependence of the observed evolutionary
trends on the cluster properties.

</DOC>
<DOC>
<DOCNO> 72169 </DOCNO>
On Brane Stabilization and the Cosmological Constant


  We address the problem of the cosmological constant within the
Randall-Sundrum scenario with a brane stabilization mechanism. We consider
brane tensions of general form. We examine the conditions under which a small
change of the positive tension of the first brane can be absorbed in a small
modification of the two-brane configuration, instead of manifesting itself as a
cosmological constant. We demonstrate that it is possible to have a
cosmological constant in the range predicted by recent observational data, if
there is an ultraviolet cutoff of order 10 TeV in the contributions to the
brane tension from vacuum fluctuations.

</DOC>
<DOC>
<DOCNO> 119189 </DOCNO>
Merging history as a function of halo environment


  According to the hierarchical scenario, galaxies form via merging and
accretion of small objects. Using N-body simulations, we study the frequency of
merging events in the history of the halos. We find that at z<~2 the merging
rate of the overall halo population can be described by a simple power law
(1+z)^3. The main emphasis of the paper is on the effects of environment of
halos at the present epoch (z=0). We find that the halos located inside
clusters have formed earlier (dz \approx 1) than isolated halos of the same
mass. At low redshifts (z<1), the merger rate of cluster halos is 3 times lower
than that of isolated halos and 2 times lower than merger rate of halos that
end up in groups by z=0. At higher redshifts (z~1-4), progenitors of cluster
and group halos have 3--5 times higher merger rates than isolated halos. We
briefly discuss implications of our results for galaxy evolution in different
environments.

</DOC>
<DOC>
<DOCNO> 121521 </DOCNO>
The Orbital Period of Intermediate Polar 1WGA J1958.2+3232


  The detection of the orbital period of 4.36his reported for the new
Intermediate Polar 1 WGA 1958.2+3232. The orbital period was derived from
time-resolved photometric and spectral observations. We also confirmed the 733
sec spin period of the White Dwarf consistent with the X-ray pulsations and
were able to distinguish the beat period in the light curve. Strong modulations
with orbital period are detected in the emission spectral lines from spectral
observations. They show the presence of a bright hot spot on the edge of the
accretion disk.
  The parameters of this recently discovered Intermediate Polar are determined.

</DOC>
<DOC>
<DOCNO> 117652 </DOCNO>
A Simple BATSE Measure of GRB Duty Cycle


  We introduce a definition of gamma-ray burst (GRB) duty cycle that describes
the GRB's efficiency as an emitter; it is the GRB's average flux relative to
the peak flux. This GRB duty cycle is easily described in terms of measured
BATSE parameters; it is essentially fluence divided by the quantity peak flux
times duration. Since fluence and duration are two of the three defining
characteristics of the GRB classes identified by statistical clustering
techniques (the other is spectral hardness), duty cycle is a potentially
valuable probe for studying properties of these classes.

</DOC>
<DOC>
<DOCNO> 11374 </DOCNO>
Saddles in the energy landscape probed by supercooled liquids


  We numerically investigate the supercooled dynamics of two simple model
liquids exploiting the partition of the multi-dimension configuration space in
basins of attraction of the stationary points (inherent saddles) of the
potential energy surface. We find that the inherent saddles order and potential
energy are well defined functions of the temperature T. Moreover, decreasing T,
the saddle order vanishes at the same temperature (T_MCT) where the inverse
diffusivity appears to diverge as a power law. This allows a topological
interpretation of T_MCT: it marks the transition from a dynamics between basins
of saddles (T>T_MCT) to a dynamics between basins of minima (T<T_MCT).

</DOC>
<DOC>
<DOCNO> 119148 </DOCNO>
The Bispectrum: From Theory to Observations


  The bispectrum is the lowest-order statistic sensitive to the shape of
structures generated by gravitational instability and is a potentially powerful
probe of galaxy biasing and the Gaussianity of primordial fluctuations.
Although the evolution of the bispectrum is well understood theoretically from
non-linear perturbation theory and numerical simulations, applications to
galaxy surveys require a number of issues to be addressed. In this paper we
consider the effect on the bispectrum of stochastic non-linear biasing, radial
redshift distortions, non-Gaussian initial conditions, survey geometry and
sampling.
  We find that: 1) bias stochasticity does not affect the use of the bispectrum
to recover the mean biasing relation between galaxies and mass, at least for
models in which the scatter is uncorrelated at large scales. 2) radial redshift
distortions do not change significantly the monopole power spectrum and
bispectrum compared to their plane-parallel values. 3) survey geometry leads to
finite volume effects which must be taken into account in current surveys
before comparison with theoretical predictions can be made. 4) sparse sampling
and survey geometry correlate different triangles leading to a breakdown of the
Gaussian likelihood approximation.
  We develop a likelihood analysis using bispectrum eigenmodes, calculated by
Monte Carlo realizations of mock surveys generated with second-order Lagrangian
perturbation theory and checked against N-body simulations. In a companion
paper we apply these results to the analysis of the bispectrum of IRAS
galaxies.

</DOC>
<DOC>
<DOCNO> 170570 </DOCNO>
Macroscopic Local Realism Incompatible with Quantum Mechanics: Failure


  We show that quantum mechanics predicts a contradiction with local hidden
variable theories for photon number measurements which have limited resolving
power, to the point of imposing an uncertainty in the photon number result
which is macroscopic in absolute terms. We show how this can be interpreted as
a failure of a new premise, macroscopic local realism.

</DOC>
<DOC>
<DOCNO> 151727 </DOCNO>
Gauged Noncommutative Wess-Zumino-Witten Models


  We investigate the Kac-Moody algebra of noncommutative Wess-Zumino-Witten
model and find its structure to be the same as the commutative case. Various
kinds of gauged noncommutative WZW models are constructed. In particular,
noncommutative $U(2)/U(1)$ WZW model is studied and by integrating out the
gauge fields, we obtain a noncommutative non-linear $\sigma$-model.

</DOC>
<DOC>
<DOCNO> 71201 </DOCNO>
Power corrections in eikonal cross sections


  We discuss power corrections associated with the infrared behavior of the
perturbative running coupling in the eikonal approximation to Drell-Yan and
other annihilation cross sections in hadron-hadron scattering. General
properties of the eikonal approximation imply that only even powers of the
energy scale are necessary.

</DOC>
<DOC>
<DOCNO> 70247 </DOCNO>
Gauge invariant Z_2 vortex vacuum textures and the SU(2) gluon


  For SU(2) lattice gauge theory, a new SO(3) cooling procedure is proposed
which removes the SU(2)/Z(2) coset fields from the lattice configurations and
reveals a Z(2) vortex vacuum texture different from the P-vortex content
obtained in the maximal center gauge. Cooling can be restricted in a
renormalization group invariant way by a parameter controlling the remaining
SO(3) action density. A gauge invariant Z(2) vortex vacuum emerges
asymptotically if cooling is not restricted. This ``vortex texture'' does not
support the string tension or a finite part of it. The SU(2) action density
associated with the new Z(2) vortex texture has a smooth extrapolation to the
continuum limit. We propose an interpretation as a mass dimension four
condensate related to the gluon condensate featuring in the operator product
expansion.

</DOC>
<DOC>
<DOCNO> 116463 </DOCNO>
One relation for self-gravitating bodies


  The relation between the gravitational potential energy, W, the central
potential, U, and the mass, M: W/U/M is considered for various homogeneous and
inhomogeneous self-gravitating bodies.

</DOC>
<DOC>
<DOCNO> 10641 </DOCNO>
Magnetic quantum critical point and superconductivity in UPt3 doped with


  Transverse-field muon spin relaxation measurements have been carried out on
the heavy-fermion superconductor UPt3 doped with small amounts of Pd. We find
that the critical Pd concentration for the emergence of the large-moment
antiferromagnetic phase is ~0.6 at.%Pd. At the same Pd content,
superconductivity is completely suppressed. The existence of a magnetic quantum
critical point in the phase diagram, which coincides with the critical point
for superconductivity, provides evidence for ferromagnetic spin-fluctuation
mediated odd-parity superconductivity, which competes with antiferromagnetic
order.

</DOC>
<DOC>
<DOCNO> 99468 </DOCNO>
Combing Euclidean buildings


  For an arbitrary Euclidean building we define a certain combing, which
satisfies the `fellow traveller property' and admits a recursive definition.
Using this combing we prove that any group acting freely, cocompactly and by
order preserving automorphisms on a Euclidean building of one of the types
A_n,B_n,C_n admits a biautomatic structure.

</DOC>
<DOC>
<DOCNO> 8030 </DOCNO>
Equation of motion approach for the Hubbard model: improved decoupling


  A new decoupling scheme is developed for the Hubbard model which provides a
unified description of the spin-symmetric (paramagnetic metallic and
insulating) phases as well as the broken-symmetry AFI phase. Independent of
magnetic ordering, the scheme yields, in the lowest order, the correct
strong-coupling bandwidth of order J (for the NN hopping model) and band gap of
order U, a non-zero critical interaction strength (above which the band gap
opens) only if same sublattice hopping (e.g., NNN hopping) is also present, and
the correct integrated spectral weights (1/2 per spin) in each band for the
half-filled model. The effects of charge and spin fluctuations, including spin
twisting due to finite spin correlation length, are investigated with a static,
random approximation. A self-consistent evaluation of the disorder-averaged
self energy within the CPA is carried out numerically. Fluctuations activate
the hopping term at first order resulting in band broadening, and the
consequent decrease in the band gap with fluctuation strength is obtained for
several U values in two and three dimensions. We find that the band gap shrinks
to zero continuously, and subsequently the density of states N(0) between the
bands grows continuously, leading to a continuous metal-insulator transition.
For finite doping there is transfer of spectral weight between the Hubbard
bands, and a qualitative change in the nature of the quasiparticle band
dispersion, with an effective doping-induced hopping strength and bandwidth of
order xt.

</DOC>
<DOC>
<DOCNO> 102884 </DOCNO>
Commuting elements in Galois groups of function fields


  We study abelian subgroups of Galois groups of function fields.

</DOC>
<DOC>
<DOCNO> 9040 </DOCNO>
Phase-coherent effects in multiterminal superconductor/normal metal


  In this report we analyse three effects which may arise in a mesoscopic
multiterminal S/N structure (two normal and two superconducting reservoirs). We
show that the Josephson critical current is a non-monotonic function of a
voltage between the normal reservoirs. The influence of the spin-polarized
electrons on the Josephson critical current was also studied. We show that if
there is a temperature difference between the normal reservoirs, a voltage
between the superconductors and normal conductors arises which oscillates as
the phase difference varies. Its magnitude is much greater than the thermoemf
in the case of the ordinary thermoelectric effect.

</DOC>
<DOC>
<DOCNO> 80853 </DOCNO>
Center vortices in MCG - finite-size and gauge-copy effects


  In SU(2) lattice gauge theory in maximal center gauge, we investigate the
dependence of center-projected Creutz ratios and the vortex density on lattice
size and the number of gauge copies. The dependence on the number of copies is
rather strong on small lattices, but almost disappears on lattices sufficiently
large compared to the expected average vortex thickness. The center-projected
string tension, evaluated on sufficiently large lattices, is in good agreement
with the full asymptotic string tension, and the vortex density scales
according to the second-order asymptotic-freedom formula.

</DOC>
<DOC>
<DOCNO> 8828 </DOCNO>
Multiparticle Biased DLA with surface diffusion: a comprehensive model


  We present a complete study of the Multiparticle Biased Diffusion-Limited
Aggregation (MBDLA) model supplemented with surface difussion (SD), focusing on
the relevance and effects of the latter transport mechanism. By comparing
different algorithms, we show that MBDLA+SD is a very good qualitative model
for electrodeposition in practically all the range of current intensities {\em
provided} one introduces SD in the model in the proper fashion: We have found
that the correct procedure involves simultaneous bulk diffusion and SD,
introducing a time scale arising from the ratio of the rates of both processes.
We discuss in detail the different morphologies obtained and compare them to
the available experimental data with very satisfactory results. We also
characterize the aggregates thus obtained by means of the dynamic scaling
exponents of the interface height, allowing us to distinguish several regimes
in the mentioned interface growth. Our asymptotic scaling exponents are again
in good agreement with recent experiments. We conclude by discussing a global
picture of the influence and consequences of SD in electrodeposition.

</DOC>
<DOC>
<DOCNO> 119384 </DOCNO>
FUSE Observations of O VI in High Velocity Clouds


  We have used moderate-resolution (FWHM ~ 25 km/sec) spectra of AGNs and QSOs
observed by the Far Ultraviolet Spectroscopic Explorer (FUSE) to make the first
definitive measurements of absorption by hot gas in high velocity clouds (HVCs)
at large distances from the Galactic plane. Seven of the 11 sight lines studied
exhibit high velocity (|V(LSR)| > 100 km/sec) O VI 1031.93 A absorption with
log N(O VI) = 13.79-14.62. High velocity O VI absorption is detected in the
distant gas of H I HVC Complex C, the Magellanic Stream, several HVCs believed
to be in the Local Group, and the outer Galaxy. The fraction of O VI in HVCs
along the seven sight lines containing high velocity O VI averages about 30
percent, with a full range of 10-70 percent. The O VI detections imply that hot
(log T(K) = 5-6) collisionally-ionized gas is an important constituent of the
HVCs since O VI is difficult to produce by photoionization unless the path
lengths over which the absorption occurs are very large (>100 kpc). The
association of O VI with H I HVCs in many cases suggests that the O VI may be
produced at interfaces or mixing layers between the H I clouds and hot, low
density gas in the Galactic corona or Local Group. Alternatively, the O VI may
originate within cooling regions of hot gas clouds as they are accreted onto
the Galaxy.

</DOC>
<DOC>
<DOCNO> 116454 </DOCNO>
Physical Aspects of Axonemal Beating and Swimming


  We discuss a two-dimensional model for the dynamics of axonemal deformations
driven by internally generated forces of molecular motors. Our model consists
of an elastic filament pair connected by active elements. We derive the dynamic
equations for this system in presence of internal forces. In the limit of small
deformations, a perturbative approach allows us to calculate filament shapes
and the tension profile. We demonstrate that periodic filament motion can be
generated via a self-organization of elastic filaments and molecular motors.
Oscillatory motion and the propagation of bending waves can occur for an
initially non-moving state via an instability termed Hopf bifurcation. Close to
this instability, the behavior of the system is shown to be independent of
microscopic details of the axoneme and the force-generating mechanism. The
oscillation frequency however does depend on properties of the molecular
motors. We calculate the oscillation frequency at the bifurcation point and
show that a large frequency range is accessible by varying the axonemal length
between 1 and 50$\mu$m. We calculate the velocity of swimming of a flagellum
and discuss the effects of boundary conditions and externally applied forces on
the axonemal oscillations.

</DOC>
<DOC>
<DOCNO> 8740 </DOCNO>
Quantum Dot as Spin Filter and Spin Memory


  We consider a quantum dot in the Coulomb blockade regime weakly coupled to
current leads and show that in the presence of a magnetic field the dot acts as
an efficient spin-filter (at the single-spin level) which produces a
spin-polarized current. Conversely, if the leads are fully spin-polarized the
up or down state of the spin on the dot results in a large sequential or small
cotunneling current, and thus, together with ESR techniques, the setup can be
operated as a single-spin memory.

</DOC>
<DOC>
<DOCNO> 101377 </DOCNO>
Canonical variables and analysis on so(n,2)


  The approach of Berezin to the quantization of so(n,2) via generalized
coherent states is considered in detail. A family of n commuting observables is
found in which the basis for an associated Fock-type representation space is
expressed. An interesting feature is that computations can be done by explicit
matrix calculations in a particular basis. The basic technical tool is the
Leibniz function, the inner product of coherent states.

</DOC>
<DOC>
<DOCNO> 152561 </DOCNO>
Holography and Phenomenology


  We examine various aspects of the conjectured duality between warped AdS$_5$
geometries with boundary branes and strongly coupled (broken) conformal field
theories coupled to dynamical gravity. We also examine compactifications with
5-d gauge fields, in which case the holographic dual is a broken CFT weakly
coupled to dynamical gauge fields in addition to gravity. The holographic
picture is used to clarify a number of important phenomenological issues in
these and related models, including the questions of black hole production,
radius stabilization, early universe cosmology, and gauge coupling unification.

</DOC>
<DOC>
<DOCNO> 71928 </DOCNO>
A Short Introduction to Non-Relativistic Effective Field Theories


  I discuss effective field theories for heavy bound systems, particularly
bound systems involving two heavy quarks. The emphasis is on the relevant
concepts and on interesting physical applications and results.

</DOC>
<DOC>
<DOCNO> 121003 </DOCNO>
Intermittent behavior of cosmic mass field revealed by QSO's Ly_alpha


  The intermittent behavior of the space-scale distribution of Ly$\alpha$
transmitted flux of QSO HS1700+64 has been analyzed via a discrete wavelet
transform. We found that there are strong indications of intermittency on
scales down to about 10 $h^{-1}$ kpc. These are: 1.) the probability
distribution function of the local fluctuations of the flux is significantly
long-tailed on small scales, and 2.) the local power spectrum of the flux shows
prominent spiky structures on small scales. Moreover, the local power spectrum
averaged on regions with different sizes shows similar spiky structures.
Therefore, the random mass density field traced by the Ly$\alpha$ forests is
rougher on smaller scales, consistent with singular clustering.

</DOC>
<DOC>
<DOCNO> 152230 </DOCNO>
T-Duality and Mixed Branes


  In this article the action of T-duality on a mixed brane is studied in the
boundary state formalism. We also obtain a two dimensional mixed brane with
non-zero electric and magnetic fields, from a D$_1$-brane.

</DOC>
<DOC>
<DOCNO> 69966 </DOCNO>
Proton polarizability contribution to the hydrogen hyperfine splitting


  The contribution of the proton polarizability to the hydrogen hyperfine
splitting is evaluated on the basis of modern experimental and theoretical
results on the proton polarized structure functions. The value of this
correction is equal to 1.4 ppm.

</DOC>
<DOC>
<DOCNO> 117225 </DOCNO>
Coherent control of enrichment and conversion of molecular spin isomers


  A theoretical model of nuclear spin conversion in molecules controlled by an
external electromagnetic radiation resonant to rotational transition has been
developed. It has been shown that one can produce an enrichment of spin isomers
and influence their conversion rates in two ways, through coherences and
through level population change induced by radiation. Influence of conversion
is ranged from significant speed up to almost complete inhibition of the
process by proper choice of frequency and intensity of the external field.

</DOC>
<DOC>
<DOCNO> 10190 </DOCNO>
Application of the Exact Muffin-Tin Orbitals Theory: the Spherical Cell


  We present a self-consistent electronic structure calculation method based on
the {\it Exact Muffin-Tin Orbitals} (EMTO) Theory developed by O. K. Andersen,
O. Jepsen and G. Krier (in {\it Lectures on Methods of Electronic Structure
Calculations}, Ed. by V. Kumar, O.K. Andersen, A. Mookerjee, Word Scientific,
1994 pp. 63-124) and O. K. Andersen, C. Arcangeli, R. W. Tank, T.
Saha-Dasgupta, G. Krier, O. Jepsen, and I. Dasgupta, (in {\it Mat. Res. Soc.
Symp. Proc.} {\bf 491}, 1998 pp. 3-34). The EMTO Theory can be considered as an
{\it improved screened} KKR (Korringa-Kohn-Rostoker) method which is able to
treat large overlapping potential spheres. Within the present implementation of
the EMTO Theory the one electron equations are solved exactly using the Green's
function formalism, and the Poisson's equation is solved within the {\it
Spherical Cell Approximation} (SCA). To demonstrate the accuracy of the
SCA-EMTO method test calculations have been carried out.

</DOC>
<DOC>
<DOCNO> 71940 </DOCNO>
P and T Odd Asymmetries in Lepton Flavor Violating Tau Decays


  We calculated the differential cross sections of the processes in which one
of the pair created tau particles at an e^+ e^- collider decays into lepton
flavor violating final states e.g. tau -> mu gamma, tau -> 3 mu, tau -> mu ee.
Using the correlations between angular distributions of both sides of tau
decays, we can obtain information on parity and CP violations of lepton flavor
non-conserving interactions. The formulae derived here are useful in
distinguishing different models, since each model of physics beyond the
standard model predicts different angular correlations. We also calculate
angular distributions of the major background process to tau -> l gamma search,
namely tau -> l nu \bar{\nu} gamma, and discuss usefulness of the angular
correlation for background suppression.

</DOC>
<DOC>
<DOCNO> 100410 </DOCNO>
Sheaf Cohomolog and Free Resolutions over Exterior Algebras


  In this paper we derive an explicit version of the
Bernstein-Gel'fand-Gel'fand (BGG) correspondence between bounded complexes of
coherent sheaves on projective space and minimal doubly infinite free
resolutions over its ``Koszul dual'' exterior algebra. This leads to an
efficient method for machine computation of the cohomology of sheaves. Among
the facts about the BGG correspondence that we derive is that taking homology
of a complex of sheaves corresponds to taking the ``linear part'' of a
resolution over the exterior algebra.
  Using these results we give a constructive proof of the existence of a
Beilinson monad for a sheaf on projective space. The explicitness of our
version allows us to to prove two conjectures about the morphisms in the monad.
  Along the way we prove a number of results about minimal free resolutions
over an exterior algebra. For example, we show that such resolutions are
eventually dominated by their "linear parts" in the sense that erasing all
terms of degree $>1$ in the complex yields a new complex which is eventually
exact.

</DOC>
<DOC>
<DOCNO> 14130 </DOCNO>
Indirect Interaction of Solid-State Qubits via Two-Dimensional Electron


  We propose a mechanism of long-range coherent coupling between nuclear spins
to be used as qubits in solid-state semiconductor-heterojunction quantum
information processing devices. The coupling is via localized donor electrons
which in turn interact with the two-dimensional electron gas. An effective
two-spin interaction Hamiltonian is derived and the coupling strength is
evaluated. We also discuss mechanisms of qubit decoherence and consider
possibilities for gate control of the interaction between neighboring qubits.
The resulting quantum computing scheme retains all the gate-control and
measurement aspects of earlier approaches, but allows qubit spacing at
distances of order 100nm, attainable with the present-day semiconductor device
technologies.

</DOC>
<DOC>
<DOCNO> 101639 </DOCNO>
Differential operators and the loop group via chiral algebras


  Let $G$ be an algebraic group and let $\widetilde{\mathfrak g}$ be the
corresponding affine algebra on some level. Consider the induced module
$V:=Ind^{\widetilde{\mathfrak g}}_{{\mathfrak g}[[t]](O_{G[[t]]})$, where
$O_{G[[t]]}$ is the ring of regular functions on the group $G[[t]]$.
  In this paper we show that $V$ is naturally a vertex operator algebra, which
is "responsible" for D-modules on the loop group $G((t))$. Using the techiques
of VOA we show that $V$ is in fact a bimodule over the affine algebra. In
addition, we show that $V$ possesses a remarkable property related to its BRST
reduction with respect to $\widetilde{\mathfrak g}$.
  This paper has a considerable intersection with a recent preprint of
Gorbunov, Malikov and Schechtman.

</DOC>
<DOC>
<DOCNO> 116537 </DOCNO>
A unified approach for the solution of the Fokker-Planck equation


  This paper explores the use of a discrete singular convolution algorithm as a
unified approach for numerical integration of the Fokker-Planck equation. The
unified features of the discrete singular convolution algorithm are discussed.
It is demonstrated that different implementations of the present algorithm,
such as global, local, Galerkin, collocation, and finite difference, can be
deduced from a single starting point. Three benchmark stochastic systems, the
repulsive Wong process, the Black-Scholes equation and a genuine nonlinear
model, are employed to illustrate the robustness and to test accuracy of the
present approach for the solution of the Fokker-Planck equation via a
time-dependent method. An additional example, the incompressible Euler
equation, is used to further validate the present approach for more difficult
problems. Numerical results indicate that the present unified approach is
robust and accurate for solving the Fokker-Planck equation.

</DOC>
<DOC>
<DOCNO> 152078 </DOCNO>
Representations of superconformal algebras in the AdS_7/4/CFT_6/3


  We perform a general analysis of representations of the superconformal
algebras OSp(8/4,R) and OSp(8*/2N) in harmonic superspace. We present a
construction of their highest-weight UIR's by multiplication of the different
types of massless conformal superfields ("supersingletons"). In particular, all
"short multiplets" are classified. Representations undergoing shortening have
"protected dimension" and may correspond to BPS states in the dual supergravity
theory in anti-de Sitter space. These results are relevant for the
classification of multitrace operators in boundary conformally invariant
theories as well as for the classification of AdS black holes preserving
different fractions of supersymmetry.

</DOC>
<DOC>
<DOCNO> 10117 </DOCNO>
Valence electronic structure of Mn in undoped and doped lanthanum


  Relative $K$ x-ray intensities of $Mn$ in $Mn$, $MnO_{2}$, $LaMnO_{3}$ and
$La_{0.7}B_{0.3}MnO_{3}$ ($B$ = $Ca$, $Sr$, and $Ce$) systems have been
measured following excitation by 59.54 keV $\gamma$-rays from a 200 mCi
$^{241}$Am point-source. The measured results for the compounds deviate
significantly from the results of pure $Mn$. Comparison of the experimental
data with the multiconfiguration Dirac-Fock (MCDF) effective atomic model
calculations indicates reasonable agreement with the predictions of ionic model
for the doped {manganites except} that the electron doped
$La_{0.7}Ce_{0.3}MnO_{3}$ and hole doped $La_{0.7}Ca_{0.3}MnO_{3}$ compounds
show some small deviations. The results of $MnO_{2}$ and $LaMnO_{3}$ deviate
considerably from the predictions of the ionic model. Our measured
$K\beta/K\alpha$ ratio of $Mn$ in $La_{0.7}Ca_{0.3}MnO_{3}$ cannot be explained
as a linear superposition of $K\beta/K\alpha$ ratios of $Mn$ for the end
members which is in contrast to the recent proposal by Tyson et al. from their
$Mn$ $K\beta$ spectra.

</DOC>
<DOC>
<DOCNO> 8904 </DOCNO>
Zero temperature correlations in trapped Bose-Einstein condensates


  We introduce a family of correlated trial wave functions for the $N$-particle
ground state of an interacting Bose gas in a harmonic trap. For large $N$, the
correlations lead to a relative energy decrease of a fraction $3/5N$, compared
to mean field Gross-Pitaevskii theory. The kinetic energy in the weakly
confining direction turns out to be most sensitive to our correlations and,
remarkably, is higher by as much as a few per cent for condensates with atom
numbers of a few thousand. Thus, the predicted deviations from Gross-Pitaevskii
theory originating from ground state correlations might be observed in momentum
distribution measurements of small condensates.

</DOC>
<DOC>
<DOCNO> 85525 </DOCNO>
On the existence of a gyroscope in spaces with affine connections and


  Conditions for the existence of a gyroscope in spaces with affine connections
and metrics are found. They appear as special types of Fermi-Walker transports
for vector fields, lying in a subspace, orthogonal to the velocity vector field
of an observer.
  PACS numbers: 04.20Cv, 04.90.+e, 04.50.+h, 02.40.Ky

</DOC>
<DOC>
<DOCNO> 68344 </DOCNO>
Free energy of an SU(2) monopole-antimonopole pair


  We present a high-statistic numerical study of the free energy of a
monopole-antimonopole pair in pure SU(2) theory. We find that the
monopole-antimonopole interaction potential exhibits a screened behavior, as
one would expect in presence of a monopole condensate. Screening occurs both in
the low-temperature, confining phase of the theory, and in the high-temperature
deconfined phase, with no evidence of a discontinuity of the screening mass
across the transition. The mass of the object responsible for the screening at
low temperature is approximately twice the established value for the lightest
glueball, indicating a prevalent coupling to glueball excitations. At high
temperature, the screening mass increases. We contrast the behavior of the
quantum system with that of the corresponding classical system, where the
monopole-antimonopole potential is of the Coulomb type.

</DOC>
<DOC>
<DOCNO> 12145 </DOCNO>
Enhanced photon production from quark-gluon plasma: Finite-lifetime


  Photon production from a thermalized quark-gluon plasma of finite lifetime is
studied directly in real time with a nonequilibrium formulation that includes
off-shell (energy nonconserving) effects. To lowest order we find that
production of direct photons form a quark-gluon plasma of temperature T ~ 200
MeV and lifetime t ~ 10-20 fm/c is strongly enhanced by off-shell (anti)quark
bremsstrahlung q(\bar{q})->q(\bar{q})\gamma. The yield from this nonequilibrium
finite-lifetime effect dominates over those obtained from higher order
equilibrium rate calculations in the range of energy E > 2 GeV and falls off
with a power law for E >> T.

</DOC>
<DOC>
<DOCNO> 121133 </DOCNO>
How many young star clusters exist in the Galactic center?


  We study the evolution and observability of young compact star clusters
within about 200pc of the Galactic center. Calculations are performed using
direct N-body integration on the GRAPE-4, including the effects of both stellar
and binary evolution and the external influence of the Galaxy. The results of
these detailed calculations are used to calibrate a simplified model applicable
over a wider range of cluster initial conditions. We find that clusters within
200 pc from the Galactic center dissolve within about 70 Myr. However, their
projected densities drop below the background density in the direction of the
Galactic center within 20 Myr, effectively making these clusters undetectable
after that time. Clusters farther from the Galactic center but at the same
projected distance are more strongly affected by this selection effect, and may
go undetected for their entire lifetimes. Based on these findings, we conclude
that the region within 200 pc of the Galactic center could easily harbor some
50 clusters with properties similar to those of the Arches or the Quintuplet
systems.

</DOC>
<DOC>
<DOCNO> 100506 </DOCNO>
Orbifold Hodge numbers of the wreath product orbifolds


  We prove that the wreath product orbifolds studied earlier by the first
author provide a large class of higher dimensional examples of orbifolds whose
orbifold Hodge numbers coincide with the ordinary ones of suitable resolutions
of singularities. We also make explicit conjectures on elliptic genera for the
wreath product orbifolds.

</DOC>
<DOC>
<DOCNO> 116380 </DOCNO>
The periodic table of elementary particles


  All leptons, quarks, and gauge bosons can be placed in the periodic table of
elementary particles. The periodic table is derived from dualities of string
theory and a Kaluza-Klein substructure for the six extra spatial dimensions. As
a molecule is the composite of atoms with chemical bonds, a hadron is the
composite of elementary particles with hadronic bonds. The masses of elementary
particles and hadrons can be calculated using the periodic table with only four
known constants: the number of the extra spatial dimensions in the superstring,
the mass of electron, the mass of Z=B0, and the fine structure constant for the
magnetic field. The calculated masses are in good agreement with the observed
values. For examples, the calculated masses for the top quark, neutron, and
pion are 176.5 GeV, 939.54MeV, and 135.01MeV in excellent agreement with the
observed masses, 176 =B1 13 GeV, 939.57 MeV, and 134.98 MeV, respectively. The
masses of 110 hadrons are calculated. The overall average difference between
the calculated masses and the observed masses for all hadrons is 0.29 MeV. The
periodic table of elementary particles provides the most comprehensive
explanation and calculation for the masses of elementary particles and hadrons.

</DOC>
<DOC>
<DOCNO> 119623 </DOCNO>
Reionization by Hard Photons: I. X-rays from the First Star Clusters


  Observations of the Ly-alpha forest at z~3 reveal an average metallicity
Z~0.01 Z_solar. The high-redshift supernovae that polluted the IGM also
accelerated relativistic electrons. Since the energy density of the CMB scales
as (1+z)^4, at high redshift these electrons cool via inverse Compton
scattering. Thus, the first star clusters emit X-rays. Unlike stellar UV
ionizing photons, these X-rays can escape easily from their host galaxies. This
has a number of important physical consequences: (i) Due to their large mean
free path, these X-rays can quickly establish a universal ionizing background
and partially reionize the universe in a gradual, homogeneous fashion. If
X-rays formed the dominant ionizing background, the universe would have more
closely resembled a single-phase medium, rather than a two-phase medium. (ii)
X-rays can reheat the universe to higher temperatures than possible with UV
radiation. (iii) X-rays counter the tendency of UV radiation to
photo-dissociate H2, an important coolant in the early universe, by promoting
gas phase H2 formation. The X-ray production efficiency is calibrated to local
observations of starburst galaxies, which imply that ~10% of the supernova
energy is converted to X-rays. While direct detection of sources in X-ray
emission is difficult, the presence of relativistic electrons at high redshift
and thus a minimal level of X-ray emission may be inferred by synchrotron
emission observations with the Square Kilometer Array. These sources may
constitute a significant fraction of the unresolved hard X-ray background, and
can account for both the shape and amplitude of the gamma-ray background. This
paper discusses the existence and observability of high-redshift X-ray sources,
while a companion paper models the detailed reionization physics and chemistry.

</DOC>
<DOC>
<DOCNO> 10214 </DOCNO>
Specific heat of the ideal gas obeying the generalized exclusion


  We calculate the specific heat of the ideal gas obeying the generalized
exclusion statistics (GES) in the continuum model and the tight binding model
numerically. In the continuum model of 3-d space, the specific heat increases
with statistical parameter at low temperature whereas it decreases with
statistical parameter at high temperature. We find that the critical
temperature normalized by $\mu_f$ (Fermi energy) is 0.290. The specific heat of
2-d space was known to be independent of $g$ in the continuum model, but it
varies with $g$ drastically in the tight-binding model. From its unique
behavior, identification of GES particles will be possible from the specific
heat.

</DOC>
<DOC>
<DOCNO> 13769 </DOCNO>
Influence of gauge fluctuations on fermion pairing order parameter


  Using a prototype model, we study the influence of gauge fluctuations on
fermion pairing order parameter which has the gauge symmetry, and demonstrate
that the gauge fluctuations can destroy the long range order of the fermion
pairing order parameter, and make it only have short range correlation. If this
parameter is a superconducting order parameter, we show that the Meissner
effect of the system keeps intact, and the system is in the superconducting
state even though the long range order of the superconducting order parameter
is destroied by the gauge fluctuations. Our calculations support that the
pseudo-gap region of the high Tc cuprate superconductivity is a spin pseudo-gap
region rather than an electron pre-paired region.

</DOC>
<DOC>
<DOCNO> 120468 </DOCNO>
High frequencies in the power spectrum of Cyg X-1 in the hard and soft


  We analyzed a large number of RXTE/PCA observations of Cyg X-1 in the hard
and soft spectral states with total exposure time of ~190 and ~10 ksec
respectively and time resolution better than ~250us in order to investigate its
variability down to a few milliseconds time scales. The model of modifications
of the power density spectra due to the dead time effect was tested using RXTE
observations of an extremely bright source - Sco X-1. The results of these
tests demonstrated, that although some problems still remain, for sources like
Cyg X-1 (which is an order of magnitude less bright than Sco X-1) present
knowledge of the instrument is sufficient to reliably analyze the power spectra
in the kHz frequency range.
  In both spectral states of Cyg X-1 we detected statistically significant
variability up to ~150-300 Hz with a fractional rms amplitude above 100 Hz at
the level of ~2-3%. The power spectrum in the hard state shows a steepening at
frequency of ~40-80 Hz with the power law slope changing from ~1.7 to ~2.3-2.4.
In the soft state the slope of power spectrum changes from ~1 to ~2 at the
frequency of ~15-20 Hz without any evidence of further steepening up to
\~100-150 Hz. These break frequencies represent the highest characteristic
frequencies detected in the power density spectrum of Cyg X-1 so far.

</DOC>
<DOC>
<DOCNO> 151147 </DOCNO>
On the strong coupling behavior of heterotic and type I orbifolds


  We study the bulk effective theory of a class of orbifolds of the type IIB
string with D5-branes, compactified to four dimensions. These constructions are
connected, in a region of their moduli space, to some orbifolds of the type I
and heterotic string. We compare the effective actions through the coupling of
the R^2 term, and we argue that these orbifolds provide non-perturbative
deformations of the latter, in which the gauge group is entirely
non-perturbative.

</DOC>
<DOC>
<DOCNO> 11792 </DOCNO>
n-Alkyl Thiol Head Group Interactions with the Au(111) Surface


  State-of-the-art first principles calculations based on density functional
theory were performed on CH_3(CH_2)_{n-1}S-Au(111) systems. We show that
the adsorption site of methylthiolate at low coverage on the Au(111) surface is
the fcc site, not the hcp site as has been recently reported. Further, we
report results for chain length dependency and the electronic structure of the
system.

</DOC>
<DOC>
<DOCNO> 99283 </DOCNO>
The invariants of the Clifford groups


  The automorphism group of the Barnes-Wall lattice L_m in dimension 2^m (m not
3) is a subgroup of index 2 in a certain ``Clifford group'' C_m (an
extraspecial group of order 2^(1+2m) extended by an orthogonal group). This
group and its complex analogue CC_m have arisen in recent years in connection
with the construction of orthogonal spreads, Kerdock sets, packings in
Grassmannian spaces, quantum codes, Siegel modular forms and spherical designs.
  In this paper we give a simpler proof of Runge's 1996 result that the space
of invariants for C_m of degree 2k is spanned by the complete weight
enumerators of the codes obtained by tensoring binary self-dual codes of length
2k with the field GF(2^m); these are a basis if m >= k-1. We also give new
constructions for L_m and C_m: let M be the Z[sqrt(2)]-lattice with Gram matrix
[2, sqrt(2); sqrt(2), 2]. Then L_m is the rational part of the mth tensor power
of M, and C_m is the automorphism group of this tensor power. Also, if C is a
binary self-dual code not generated by vectors of weight 2, then C_m is
precisely the automorphism group of the complete weight enumerator of the
tensor product of C and GF(2^m). There are analogues of all these results for
the complex group CC_m, with ``doubly-even self-dual code'' instead of
``self-dual code''.

</DOC>
<DOC>
<DOCNO> 9750 </DOCNO>
Evolution of Biological Complexity


  In order to make a case for or against a trend in the evolution of complexity
in biological evolution, complexity needs to be both rigorously defined and
measurable. A recent information-theoretic (but intuitively evident) definition
identifies genomic complexity with the amount of information a sequence stores
about its environment. We investigate the evolution of genomic complexity in
populations of digital organisms and monitor in detail the evolutionary
transitions that increase complexity. We show that because natural selection
forces genomes to behave as a natural ``Maxwell Demon'', within a fixed
environment genomic complexity is forced to increase.

</DOC>
<DOC>
<DOCNO> 11228 </DOCNO>
Exponents of the localization lengths in the bipartite Anderson model


  We investigate the scaling properties of the two-dimensional (2D) Anderson
model of localization with purely off-diagonal disorder (random hopping). In
particular, we show that for small energies the infinite-size localization
lengths as computed from transfer-matrix methods together with finite-size
scaling diverge with a power-law behavior. The corresponding exponents seem to
depend on the strength and the type of disorder chosen.

</DOC>
<DOC>
<DOCNO> 116316 </DOCNO>
A-Tract Induced DNA Bending is A Local Non-Electrostatic Effect


  The macroscopic curvature induced in double helical B-DNA by regularly
repeated adenine tracts (A-tracts) is a long known, but still unexplained
phenomenon. This effect plays a key role in DNA studies because it is unique in
the amount and the variety of the available experimental information and,
therefore, is likely to serve as a gate to the unknown general mechanisms of
recognition and regulation of genome sequences. The dominating idea in the
recent years was that, in general, macroscopic bends in DNA are caused by long
range electrostatic repulsion between phosphate groups when some of them are
neutralized by proximal external charges. In the case of A-tracts this may be
specifically bound solvent counterions. Here we report about molecular dynamics
simulations where a correct static curvature in a DNA fragment with phased
adenine tracts emerges spontaneously in conditions where any role of
counterions or long range electrostatic effects can be excluded.

</DOC>
<DOC>
<DOCNO> 11526 </DOCNO>
The Theory of Atom Lasers


  We review the current theory of atom lasers. A tutorial treatment of second
quantisation and the Gross-Pitaevskii equation is presented, and basic concepts
of coherence are outlined. The generic types of atom laser models are surveyed
and illustrated by specific examples. We conclude with detailed treatments of
the mechanisms of gain and output coupling.

</DOC>
<DOC>
<DOCNO> 11575 </DOCNO>
Ground state fluctuations in finite Fermi and Bose systems


  We consider a small and fixed number of fermions (bosons) in a trap. The
ground state of the system is defined at T=0. For a given excitation energy,
there are several ways of exciting the particles from this ground state. We
formulate a method for calculating the number fluctuation in the ground state
using microcanonical counting, and implement it for small systems of
noninteracting fermions as well as bosons in harmonic confinement. This exact
calculation for fluctuation, when compared with canonical ensemble averaging,
gives considerably different results, specially for fermions. This difference
is expected to persist at low excitation even when the fermion number in the
trap is large.

</DOC>
<DOC>
<DOCNO> 14025 </DOCNO>
Operator projection method applied to the single-particle Green's


  A new non-perturbative framework for many-body correlated systems is
formulated by extending the operator projection method (OPM). This method
offers a systematic expansion which enables us to project into the low-energy
structure after extracting the higher-energy hierarchy. This method also opens
a way to systematically take into account the effects of collective
excitations. The Mott-Hubbard metal-insulator transition in the Hubbard model
is studied by means of this projection beyond the second order by taking into
account magnetic and charge fluctuations in the presence of the high-energy
Mott-Hubbard structure. At half filling, the Mott-Hubbard gap is correctly
eproduced between the separated two bands. Near half filling, a strongly
renormalized low-energy single-particle excitations coexisting with the
Mott-Hubbard bands are shown to appear. Signifcance of momentum-dependent
self-energy in the results is stressed.

</DOC>
<DOC>
<DOCNO> 68979 </DOCNO>
Effects of quantum space time foam in the neutrino sector


  We discuss violations of CPT and quantum mechanics due to interactions of
neutrinos with space-time quantum foam. Neutrinoless double beta decay and
oscillations of neutrinos from astrophysical sources (supernovae, active
galactic nuclei) are analysed. It is found that the propagation distance is the
crucial quantity entering any bounds on EHNS parameters. Thus, while the bounds
from neutrinoless double beta decay are not significant, the data of the
supernova 1987a imply a bound being several orders of magnitude more stringent
than the ones known from the literature. Even more stringent limits may be
obtained from the investigation of neutrino oscillations from active galactic
nuclei sources, which have an impressive potential for the search of quantum
foam interactions in the neutrino sector.

</DOC>
<DOC>
<DOCNO> 68930 </DOCNO>
Possible Striking Signals for a Quark-Gluon Plasma at RHIC


  We believe that one can have serious reservations as to whether heavy ion
collisions (e.g. 100 GeV/n Au + 100 GeV/n Au) can lead to Thermal and Chemical
equilibrium over large regions (particularly if it is assumed this happens
whenever QGP is produced at RHIC-that is if it is produced). It is at present
not clear that the collision dynamics and times available will lead to this. An
alternate scenario proposed by Van Hove where localized in rapidity bubbles of
plasma may well be more probable, and may well occur at least some of the time,
and some of the time mainly survive to the final state. If this occurs we have
developed a series of event generators to extend and describe these phenomena.
A Van Hove type[6,7] spherical bubble at eta=0 is embedded in a resonable event
generator in qualitative agreement with Hijing etc[12]. The plasma bubble
hadronized at a temperature of 170 Mev according to the model developed by
Koch, Muller and Rafelski[21]. The amount of available bubble energy is
selected by that in a small central circular cross-section of radius approx
1.3fm or 2.5fm in 100 Gev/n Au+AU, central events The results predict Possible
Striking Signals for a QGP.
  We are also applying these techniques to investigating Kharzeev and Pisarski
bubbles of metastable vacua with odd CP.

</DOC>
<DOC>
<DOCNO> 99727 </DOCNO>
Minimal resolution of general stable vector bundles on $\PP^2$


  We study the general elements of the moduli spaces (\MM_{\PP^2} (r, c_1, c_2)
) of stable holomorphic vector bundle on $\PP^2$ and their minimal free
resolution. Incidentally, a quite easy proof of the irreducibility of
(\MM_{\PP^2} (r, c_1, c_2)) is shown.

</DOC>
<DOC>
<DOCNO> 100806 </DOCNO>
Completion of a Rational Function Sequence of Carlitz


  The exponential generating functions of {n^(n+m)} for arbitrary integer m are
expressed as rational functions of the e.g.f. of {n^(n-1)} [the tree function]
and then of the e.g.f. of {n^n} [the endofunction function].
 The coefficients in these rational functions include 2nd-order Eulerian
numbers (a result of L. Carlitz), 2nd-order Stirling numbers, and Stirling
numbers of the first kind for negative sets (in the sense of D. Loeb). Several
combinatorial identities follow.

</DOC>
<DOC>
<DOCNO> 71341 </DOCNO>
Quark-Hadron Duality in Electron Scattering


  Quark-hadron duality addresses some of the most fundamental issues in strong
interaction physics, in particular the nature of the transition from the
perturbative to non-perturbative regions of QCD. I summarize recent
developments in quark-hadron duality in lepton-hadron scattering, and outline
how duality can be studied at future high-luminosity facilities such as
Jefferson Lab at 12 GeV, or an electron-hadron collider such as EPIC.

</DOC>
<DOC>
<DOCNO> 122610 </DOCNO>
LRG J0239-0134: A Ring Galaxy or a Pair of Superbubbles at z=1 ?


  The unusual morphology of LRG J0239$-$0134 at $z$ =1.062 has been interpreted
as a ring galaxy. Here we propose an alternative idea that the ring-like
morphology is attributed to a pair of superbubbles driven by the intense
starburst in the central region of this galaxy. Supporting evidence for a
superbubble model is; 1) the poststarburst nature in the central body suggests
that a burst of supernova explosions could occur at least $\sim 10^7$ yr ago,
2) the dark lane seen in the central body suggests that we observe this object
from a nearly edge-on view, and, 3) the ring-like morphology is not
inconsistent with an idea that it is a pair of superbubbles. All these pieces
of evidence for the superbubble model seem circumstantial. However, if this is
the case, this galaxy provides an important example of the superwind activity
at high redshift.

</DOC>
<DOC>
<DOCNO> 121326 </DOCNO>
EVN Observations of GRS1915+105


  We obtained EVN observations of the X-ray transient source GRS1915+105 in its
radio-loud state. In 2 images obtained before a major flare, the source is
resolved, showing two opposite asymmetric jets. This indicates that steady jets
exist also before a major flare, with an estimated velocity of 0.2-0.6c.

</DOC>
<DOC>
<DOCNO> 100169 </DOCNO>
The Hamiltonian Seifert Conjecture: Examples and Open Problems


  Hamiltonian dynamical systems tend to have infinitely many periodic orbits.
For example, for a broad class of symplectic manifolds almost all levels of a
proper smooth Hamiltonian carry periodic orbits. The Hamiltonian Seifert
conjecture is the existence problem for regular compact energy levels without
periodic orbits.
  Very little is known about how large the set of regular energy values without
periodic orbits can be. For instance, in all known examples of Hamiltonian
flows on linear spaces such energy values form a discrete set, whereas ``almost
existence theorems'' only require this set to have zero measure. We describe
constructions of Hamiltonian flows without periodic orbits on one energy level
and formulate conjectures and open problems.

</DOC>
<DOC>
<DOCNO> 40223 </DOCNO>
Measurement of B(K -> pnn)


  The experimental measurement of positive kaons decaying to a positive pion
and a neutrino, anti-neutrino pair (pnn) is reviewed. Recent results from
experiment E787 at BNL are presented: with data from 1995--97 the branching
ratio has been measured to be B(pnn) = (1.5^{+3.4}_{-1.2}) \times10^{-10}. The
future prospects for additional data in this mode are examined.

</DOC>
<DOC>
<DOCNO> 117924 </DOCNO>
Photometric Properties of Low Redshift Galaxy Clusters


  We have recently completed a comprehensive photometric survey of 27 Abell
clusters with the 8k mosaic camera on the KPNO 0.9m telescope. Preliminary
luminosity functions and dwarf-to-giant galaxy ratios have been calculated for
five galaxy clusters (A1185, A1656, A2151, A2152, and A2197). A significant
increase in the faint end slope between the inner (0.0-0.75 Mpc) and outer
(0.75-1.50 Mpc) luminosity function is measured for A2151 (H_o = 50 km/s/Mpc).
All five clusters show a significant dip in the luminosity function at M_R =
-19.5.

</DOC>
<DOC>
<DOCNO> 10525 </DOCNO>
Thermal Equation of State of Tantalum


  We have investigated the thermal equation of state of tantalum from first
principles using the Linearized Augmented Plane Wave (LAPW) and pseudopotential
methods for pressures up to 300 GPa and temperatures up to 10000 K. The
equation of state at zero temperature was computed using LAPW. For finite
temperatures, mixed basis pseudopotential computations were performed for 54
atom supercells. The vibrational contributions were obtained by computing the
partition function using the particle in a cell model, and the the finite
temperature electronic free energy was obtained from the LAPW band structures.
We discuss the behavior of thermal equation of state parameters such as the
Gr\"uneisen parameter $\gamma$, $q$, the thermal expansivity $\alpha$, the
Anderson-Gr\"uneisen parameter $\delta_T$ as functions of pressure and
temperature. The calculated Hugoniot shows excellent agreement with shock-wave
experiments. An electronic topological transition was found at approximately
200 GPa.

</DOC>
<DOC>
<DOCNO> 121407 </DOCNO>
Radial density and temperature profiles of the intracluster gas


  In this paper we have made an attempt to derive the radial profiles of
density and temperature of intracluster gas based on the two well-established
facts at present: the X-ray observed surface brightness of clusters described
by the standard beta model and the (NFW) universal density profile as the
underlying dark matter distribution. We have numerically solved the hydrostatic
equation by demanding that the volumed-averaged baryon fraction of a cluster
should asymptotically approach the universal value at its viral radius. We have
shown that the radial temperature variation derived from these constraints
differs significantly from the conventional polytropic equation of state: The
gas temperature profile may show a dramatic increase or decrease with outward
radius, depending sensitively on the beta parameter. A large beta value
(typically greater than 0.8) is required in order to ensure that the X-ray
temperature makes a drop at the virial radius. This indicates that either the
NFW profile is inappropriate to apply for the overall dark matter distribution
of clusters or other non-gravitational heating processes may play an important
role in the dynamical evolution of clusters.

</DOC>
<DOC>
<DOCNO> 8133 </DOCNO>
Steady-state mode I cracks in a viscoelastic triangular lattice


  We continue our study of the exact solutions for steady-state cracks in
ideally brittle viscoelastic lattice models by focusing on mode I in a
triangular system. The issues we address include the crack velocity versus
driving curve as well as the onset of additional bond-breaking, signaling the
emergence of complex spatio-temporal behavior. Somewhat surprisingly, the
critical velocity for this transition becomes a decreasing function of the
dissipation for sufficiently large values thereof. At the end, we briefly
discuss the possible relevance of our findings for experiments on mode I crack
instabilities.

</DOC>
<DOC>
<DOCNO> 152100 </DOCNO>
Gauge Fields, Scalars, Warped Geometry, and Strings


  We review results on several interesting phenomena in warped
compactifications of M theory, as presented at Strings 2000. The behavior of
gauge fields in dimensional reduction from $d+1$ to $d$ dimensions in various
backgrounds is explained from the point of view of the holographic duals (and a
point raised in the question session at the conference is addressed). We
summarize the role of additional fields (in particular scalar fields) in 5d
warped geometries in making it possible for Poincare-invariant domain wall
solutions to exist to a nontrivial order in a controlled approximation scheme
without fine-tuning of parameters in the $5d$ action (and comment on the status
of the singularities arising in the general relativistic description of these
solutions). Finally, we discuss briefly the emergence of excitations of wrapped
branes in warped geometries whose effective thickness, as measured along the
Poincare slices in the geometry, grows as the energy increases.

</DOC>
<DOC>
<DOCNO> 170209 </DOCNO>
Why the Disjunction in Quantum Logic is Not Classical


  The quantum logical `or' is analyzed from a physical perspective. We show
that it is the existence of EPR-like correlation states for the quantum
mechanical entity under consideration that make it nonequivalent to the
classical situation. Specifically, the presence of potentiality in these
correlation states gives rise to the quantum deviation from the classical
logical `or'. We show how this arises not only in the microworld, but also in
macroscopic situations where EPR-like correlation states are present. We
investigate how application of this analysis to concepts could alleviate some
well known problems in cognitive science.

</DOC>
<DOC>
<DOCNO> 83342 </DOCNO>
All Pairs Shortest Paths using Bridging Sets and Rectangular Matrix


  We present two new algorithms for solving the {\em All Pairs Shortest Paths}
(APSP) problem for weighted directed graphs. Both algorithms use fast matrix
multiplication algorithms.
  The first algorithm solves the APSP problem for weighted directed graphs in
which the edge weights are integers of small absolute value in $\Ot(n^{2+\mu})$
time, where $\mu$ satisfies the equation $\omega(1,\mu,1)=1+2\mu$ and
$\omega(1,\mu,1)$ is the exponent of the multiplication of an $n\times n^\mu$
matrix by an $n^\mu \times n$ matrix. Currently, the best available bounds on
$\omega(1,\mu,1)$, obtained by Coppersmith, imply that $\mu<0.575$. The running
time of our algorithm is therefore $O(n^{2.575})$. Our algorithm improves on
the $\Ot(n^{(3+\omega)/2})$ time algorithm, where $\omega=\omega(1,1,1)<2.376$
is the usual exponent of matrix multiplication, obtained by Alon, Galil and
Margalit, whose running time is only known to be $O(n^{2.688})$.
  The second algorithm solves the APSP problem {\em almost} exactly for
directed graphs with {\em arbitrary} non-negative real weights. The algorithm
runs in $\Ot((n^\omega/\eps)\log (W/\eps))$ time, where $\eps>0$ is an error
parameter and W is the largest edge weight in the graph, after the edge weights
are scaled so that the smallest non-zero edge weight in the graph is 1. It
returns estimates of all the distances in the graph with a stretch of at most
$1+\eps$. Corresponding paths can also be found efficiently.

</DOC>
<DOC>
<DOCNO> 70969 </DOCNO>
Model independent constraints on contact interactions from LEP2


  We quantitatively discuss the possibility of deriving model-independent
constraints on the general four-fermion contact interaction couplings, from the
currently available data on the two-fermion production processes
$e^+e^-\to\mu^+\mu^-$, $b\bar{b}$ and $c\bar{c}$ with unpolarized initial
beams. The method is essentially based on particular, simple, combinations of
the measured total cross section and forward-backward asymmetry that allow
partial separation of the helicity cross sections, and the combination of
experimental data obtained at the different energies of TRISTAN, LEP1 and LEP2.

</DOC>
<DOC>
<DOCNO> 71660 </DOCNO>
The Dispersive Approach to Electroweak Processes in the Background


  We propose a new method to compute amplitudes of electroweak processes in the
strong background magnetic field, using $\gamma\to e^+e^-$ as an example. We
show that the {\it moments} of $\gamma\to e^+e^-$ width are proportional to the
derivatives of photon polarization function at the zero energy. Hence, the
pair-production width can be easily calculated from the latter by the inverse
Mellin transform. The prospects of our approach are commented.

</DOC>
<DOC>
<DOCNO> 121673 </DOCNO>
The Puzzle of the Lyman Continuum Polarization of QSOs


  Recent spectropolarimetry of QSOs has revealed a surprising rise in
polarization in the Lyman continuum of several objects. We discuss several
recent attempts to interpret this feature, including the role of Lyman limit
absorption in PG 1222+228. We present new theoretical results involving
electron scattering in a hot corona or wind above an accretion disk, and
polarization resulting from the relativistic returning radiation. These
mechanisms can lead to potentially observable polarization at short
wavelengths, but neither has quantitative success in fitting the observed Lyman
continuum polarization rises. A renewed capability for ultraviolet
spectropolarimetry from space is urgently needed to provide further clues to
the nature of this phenomenon.

</DOC>
<DOC>
<DOCNO> 40214 </DOCNO>
Observation of neutral current charm production in $\nu_{\mu}Fe$


  We report on the first observation of open charm production in neutral
current deep inelastic neutrino scattering as seen in the NuTeV detector at
Fermilab. The production rate is shown to be consistent with a pure gluon-$%
Z^{0}$ boson production model, and the observed level of charm production is
used to determine the effective charm mass. As part of our analysis, we also
obtain a new measurement for the proton-nucleon charm production cross section
at $\sqrt{s}=38.8$ GeV.

</DOC>
<DOC>
<DOCNO> 68452 </DOCNO>
Multiplicity distribution tails at high energies


  The idea that the hard channels may dominate in the very high multiplicity
processes is investigated. Quantitative realization of the `hard Pomeron', deep
inelastic scattering and large-angle annihilation mechanism combinations are
considered in the pQCD frame for this purpose.

</DOC>
<DOC>
<DOCNO> 85111 </DOCNO>
Negative Energy Condition and Black Holes on the Brane


  We propose that for non-localizable energy distribution the relevant energy
condition is determined by the gravitational field energy which is negative for
positive non-gravitational energy. That is negativity of the non-localized
energy is the "positive" energy condition. This would have direct application
and relevance for a black hole on the brane which would be sitting in a trace
free stresses induced by the Weyl curvature of the bulk.

</DOC>
<DOC>
<DOCNO> 123224 </DOCNO>
A comment on trans-Planckian physics in inflationary universe


  There are several works searching for a clue of trans-Planckian physics on
the primordial density perturbation spectrum. Here we would like to point out
an important aspect which has been overlooked so far. When we consider a model
in which the primordial density perturbation spectrum is modified due to
trans-Planckian physics, the energy density of fluctuations of the inflaton
field necessarily becomes significantly large, and hence its back reaction to
the cosmic expansion rate cannot be neglected.

</DOC>
<DOC>
<DOCNO> 40000 </DOCNO>
Total Cross Sections


  The measurements of the hadron-hadron total cross sections are the first
measurements performed when a new hadron accelerator opens up a new energy
region; the measurements were made as function of the incoming beam momentum or
c.m. energy and have often been repeated with improved accuracy and finer
energy spacing.

</DOC>
<DOC>
<DOCNO> 99670 </DOCNO>
Fourier's Law: a Challenge for Theorists


  We present a selective overview of the current state of our knowledge (more
precisely of ourignorance) regarding the derivation of Fourier's Law, ${\bf
J}(\br) =-\kappa {\bf \nabla}T(\br)$; ${\bf J}$ the heat flux, $T$ the
temperature and $\kappa$, the heat conductivity. This law is empirically well
tested for both fluids and crystals, when the temperature varies slowly on the
microscopic scale, with $\kappa$ an intrinsic property which depends only on
the system's equilibrium parameters, such as the local temperature and density.
There is however at present no rigorous mathematical derivation of Fourier's
law and ipso facto of Kubo's formula for $\kappa$, involving integrals over
equilibrium time correlations, for any system (or model) with a deterministic,
e.g. Hamiltonian, microscopic evolution.

</DOC>
<DOC>
<DOCNO> 69989 </DOCNO>
Colour Deconfinement in Nuclear Collisions


  QCD predicts that strongly interacting matter will undergo a transition from
a state of hadronic constituents to a plasma of unbound quarks and gluons. We
first survey the conceptual features of this transition and its description in
finite temperature lattice QCD, before we address its experimental
investigation through high energy nucleus-nucleus collisions. After considering
the conditions achievable in such collisions, we discuss the possible probes to
check if the produced medium in its early stages was indeed deconfined. We then
elaborate the method that has emerged and the results which were obtained using
the most extensively studied deconfinement probe, the suppression of charmonium
production. In closing, we discuss possible supporting information provided
through the study of soft hadronic probes.

</DOC>
<DOC>
<DOCNO> 120426 </DOCNO>
High Resolution Observations of X-ray Absorbers/Emitters


  We present photoionization and collisional ionization models, and their
application to three important fields: (a) the Warm Absorbers/Emitters in type
1 AGN, (b) the Warm Reflectors in Type 2 AGN, and (c) X-ray absorption of
background quasars by intergalactic gas. A number of cases are investigated,
and the dependences of the main parameters explored.

</DOC>
<DOC>
<DOCNO> 69472 </DOCNO>
Anomalous Multiplicity Fluctuations from Phase Transitions in Heavy Ion


  Event-by-event fluctuations and correlations between particles produced in
relativistic nuclear collisions are studied. The fluctuations in positive,
negative, total and net charge are closely related through correlations. In the
event of a phase transitions to a quark-gluon plasma, fluctuations in total and
net charge can be enhanced and reduced respectively which, however, is very
sensitive to the acceptance and centrality. If the colliding system experiences
strong density fluctuations due, e.g., to droplet formation in a first-order
phase transition, all fluctuations can be enhanced substantially. The
importance of fluctuations and correlations is exemplified by event-by-event
measurement of the multiplicities of $J/\Psi$'s and charged particles since
these observables should anti-correlate in the presence of co-mover or
anomalous absorption.

</DOC>
<DOC>
<DOCNO> 71375 </DOCNO>
Diffraction at HERA and the Confinement Problem


  We discuss HERA data on the high energy behavior of the total gamma*p cross
section and on diffraction in deep inelastic scattering. We outline their
novelty in comparison with diffraction in high energy hadron hadron scattering.
As a physical picture, we propose an interpretation in terms of QCD radiation
at small and large distances: a careful study of the transition between the two
extremes represents a new approach to the QCD confinement problem.

</DOC>
<DOC>
<DOCNO> 39706 </DOCNO>
Brief Report from the Tevatron


  We report on the B physics prospects from the Fermilab Tevatron, summarizing
the B physics goals of the CDF and DO experiments using their upgraded
detectors. We discuss the time schedule for completion of the detector upgrades
and summarize the current measurement of the CP violation parameter sin(2 beta)
at CDF.

</DOC>
<DOC>
<DOCNO> 68832 </DOCNO>
Spinodal Decomposition in High Temperature Gauge Theories


  After a rapid increase in temperature across the deconfinement temperature $%
T_{d}$, pure gauge theories exhibit unstable long wavelength fluctuations in
the approach to equilibrium. This phenomenon is analogous to spinodal
decomposition observed in condensed matter physics, and also seen in models of
disordered chiral condensate formation. At high temperature, the unstable modes
occur only in the range $0\leq k$ $\leq k_{c}$, where $k_{c}$ is on the order
of the Debye screening mass $m_D$. Equilibration always occurs via spinodal
decomposition for $SU(2) $at temperatures $T>T_{d}$ and for SU(3) for $T\gg
T_{d}$. For SU(3) at temperatures $T\gtrsim T_{d}$, nucleation may replace
spinodal decomposition as the dominant equilibration mechanism. Monte Carlo
simulations of SU(2) lattice gauge theory exhibit the predicted phenomena. The
observed value of $k_c$ is in reasonable agreement with a value predicted from
previous lattice measurements of $m_D$.

</DOC>
<DOC>
<DOCNO> 170579 </DOCNO>
Shor's Quantum Factoring Algorithm


  This paper is a written version of a one hour lecture given on Peter Shor's
quantum factoring algorithm.

</DOC>
<DOC>
<DOCNO> 70303 </DOCNO>
The Higgs masses and explicit CP violation in the gluino-axion model


  In this work, we adress the phenomenological consequences of explicit CP
violation on direct Higgs-boson searches at high energy colliders. Having a
restricted parameter space, we concentrate on the recently proposed
gluino-axion model, and investigate the CP violation capability of the model
subject to the recent experimental data. It is shown that the Higgs masses as
well as their CP compositions are quite sensitive to the supersymmetric CP
phases. The lightest Higgs is found to be nearly CP even to a good
approximation whilst the remaining two heavy scalars do not have definite CP
parities.

</DOC>
<DOC>
<DOCNO> 12513 </DOCNO>
Attractions between charged colloidal spheres mediated by correlated


  We describe arrangements of ions capable of producing short-range attractive
interactions between pairs of charged colloidal spheres in the low temperature
strongly correlated limit. For particles of radius $R$ with bare charge $Z$ and
comparable absorbed charge $-N$ ($N \sim Z$), the correlations contribution to
the spheres self-energy scales as $N^{3/2}/R$, and as $N/R$ for the interaction
energy between two touching spheres. We show that the re-arrangement of charges
due to polarization plays an insignificant role in the nature and magnitude of
the interaction.

</DOC>
<DOC>
<DOCNO> 120267 </DOCNO>
Characterising the Primordial Cosmic Perturbations


  The most general homogeneous and isotropic statistical ensemble of linear
scalar perturbations which are regular at early times, in a universe with only
photons, baryons, neutrinos, and a cold dark matter (CDM) component, is
described by a 5x5 symmetric matrix-valued generalization of the power
spectrum. This description is complete if the perturbations are Gaussian, and
even in the non-Gaussian case describes all observables quadratic in the small
perturbations. The matrix valued power spectrum describes the auto- and
cross-correlations of the adiabatic, baryon isocurvature, CDM isocurvature,
neutrino density isocurvature, and neutrino velocity isocurvature modes. In
this paper we examine the prospects for constraining or discovering
isocurvature modes using forthcoming MAP and PLANCK measurements of the cosmic
microwave background (CMB) anisotropy. We also consider the degradation in
estimates of the cosmological parameters resulting from the inclusion of these
modes. In the case of MAP measurements of the temperature alone, the
degradation is drastic. When isocurvature modes are admitted, uncertainties in
the amplitudes of the mode auto-- and cross--correlations, and in the
cosmological parameters, become of order one. With the inclusion of
polarisation (at an optimistic sensitivity) the situation improves for the
cosmological parameters but the isocurvature modes are still only weakly
constrained. Measurements with PLANCK's estimated errors are far more
constraining, especially so with the inclusion of polarisation. If PLANCK
operates as planned the amplitudes of isocurvature modes will be constrained to
less than ten per cent of the adiabatic mode and simultaneously key
cosmological parameters will be estimated to a few per cent or better.

</DOC>
<DOC>
<DOCNO> 84789 </DOCNO>
The Life and Times of Extremal Black Holes


  Charged extremal black holes cannot fully evaporate through the Hawking
effect and are thus long lived. Over their lifetimes, these black holes take
part in a variety of astrophysical processes, including many that lead to their
eventual destruction. This paper explores the various events that shape the
life of extremal black holes and calculates the corresponding time scales.

</DOC>
<DOC>
<DOCNO> 10659 </DOCNO>
Magnetoresistance of Three-Constituent Composites: Percolation Near a


  Scaling theory, duality symmetry, and numerical simulations of a random
network model are used to study the magnetoresistance of a
metal/insulator/perfect conductor composite with a disordered columnar
microstructure. The phase diagram is found to have a critical line which
separates regions of saturating and non-saturating magnetoresistance. The
percolation problem which describes this line is a generalization of
anisotropic percolation. We locate the percolation threshold and determine the
t = s = 1.30 +- 0.02, nu = 4/3 +- 0.02, which are the same as in
two-constituent 2D isotropic percolation. We also determine the exponents which
characterize the critical dependence on magnetic field, and confirm numerically
that nu is independent of anisotropy. We propose and test a complete scaling
description of the magnetoresistance in the vicinity of the critical line.

</DOC>
<DOC>
<DOCNO> 118332 </DOCNO>
The elusive structure of the diffuse molecular gas: shocks or vortices


  The cold diffuse interstellar medium must harbor pockets of hot gas to
produce the large observed abundances of molecular species, the formation of
which require much more energy than available in the bulk of its volume. These
hot spots have so far escaped direct detection but observations and modeling
severely constrain their phase-space structure i.e. they must have a small
volume filling factor (a few %), surface filling factors larger than unity with
large fluctuations about average and comparable velocity structure in ``pencil
beams'' and ``large beams''. The dissipation of the non-thermal energy of
supersonic turbulence occurs in bursts, either in shocks or in the regions of
large shear at the boundary of coherent vortices. These two processes are
susceptible to generate localized hot regions in the cold medium. Yet, it is of
interest to determine which of them, if any, dominates the dissipation of
turbulence in the cold interstellar medium. In this paper, we analyze the
spatial and kinematic properties of two subsets of hydrodynamical compressible
turbulence: the regions of largest negative divergence and those of largest
vorticity and confront them with the observational constraints. We find that
these two subsets fulfill the constraints equally well. A similar analysis
should be conducted in the future on simulations of MHD turbulence.

</DOC>
<DOC>
<DOCNO> 10171 </DOCNO>
Hall coefficient and angle-resolved photoemission in systems with strong


  We examine the normal-state temperature and doping dependence of the Hall
coefficient in the context of a pair-fluctuation scenario, based on a model
where itinerant electrons are hybridized with localized electron pairs via a
charge exchange term. We show that an anomalous behavior of the Hall effect,
qualitatively similar to that observed in high-Tc superconductors, can be
attributed to the non-Fermi liquid properties of the single-particle spectral
function which exhibits pseudogap features. Our calculations are based on a
dynamical mean-field procedure which relates the transport coefficients to the
single-particle spectral function in an exact way.

</DOC>
<DOC>
<DOCNO> 117483 </DOCNO>
X-ray total mass estimate for the nearby relaxed cluster A3571


  We constrain the total mass distribution in the cluster A3571, combining
spatially resolved ASCA temperature data with ROSAT imaging data with the
assumption that the cluster is in hydrostatic equilibrium. The total mass
within r_500 (1.7/h_50 Mpc) is M_500 = 7.8[+1.4,-2.2] 10^14/ h_50 Msun at 90%
confidence, 1.1 times smaller than the isothermal estimate. The Navarro, Frenk
& White ``universal profile'' is a good description of the dark matter density
distribution in A3571. The gas density profile is shallower than the dark
matter profile, scaling as r^{-2.1} at large radii, leading to a monotonically
increasing gas mass fraction with radius. Within r_500 the gas mass fraction
reaches a value of f_gas = 0.19[+0.06,-0.03] h_50^{-3/2} (90% confidence
errors). Assuming that this value of f_gas is a lower limit for the the
universal value of the baryon fraction, we estimate the 90% confidence upper
limit of the cosmological matter density to be Omega_m < 0.4.

</DOC>
<DOC>
<DOCNO> 116850 </DOCNO>
Overview of the APT Accelerator Design


  The accelerator for the APT Project is a 100 mA CW proton linac with an
output energy of 1030 MeV. A High Energy Beam Transport (HEBT) conveys the beam
to a raster expander, that provides a large rectangular distribution at a
target/blanket (T/B) assembly. Spallation neutrons generated by the proton beam
in the T/B reacts with Helium-3 to produce tritium. The design of the APT linac
is an integrated normal-conducting (NC)/superconducting (SC) proton linac; the
machine architecture has been discussed elsewhere [1]. The NC linac consists of
a 75 keV injector, a 6.7-MeV 350-MHz RFQ (radio frequency quadrupole), a 96-MeV
700-MHz CCDTL (coupled-cavity drift-tube linac), and a 700-MHz CCL
(coupled-cavity linac), with an output energy of 211 MeV. This is followed by a
SC linac, that employs 700-MHz elliptical niobium 5-cell cavities to accelerate
the beam to the final energy. The SC linac has two sections, optimized for beam
velocities of b =0.64 and b =0.82. Each section is made up of cryomodules
containing two, three, or four 5-cell cavities, driven by 1-MW 700-MHz
klystrons. The singlet FODO lattice in the NC linac transitions to a doublet
focusing lattice in the SC linac, with conventional quadrupole magnets in the
warm inter-module spaces. This doublet lattice is continued in the HEBT. An
overview of the current linac design will be presented.

</DOC>
<DOC>
<DOCNO> 100475 </DOCNO>
Decomposition of analytic measures on groups and measure spaces


  This paper provides a new approach to proving generalizations of the F.&M.
Riesz Theorem, for example, the result of Helson and Lowdenslager, the result
of Forelli (and de Leeuw and Glicksberg), and more recent results of Yamagushi.
We study actions of a locally compact abelian group with ordered dual onto a
space of measures, and consider those measures that are analytic, that is, the
spectrum of the action on the measure is contained within the positive elements
of the dual of the group. The classical results tell us that the singular and
absolutely continuous parts of the measure (with respect to a suitable measure)
are also analytic. The approach taken in this paper is to adopt the
transference principle developed by the authors and Saeki in another paper, and
apply it to martingale inequalities of Burkholder and Garling. In this way, we
obtain a decomposition of the measures, and obtain the above mentioned results
as corollaries.

</DOC>
<DOC>
<DOCNO> 40229 </DOCNO>
Resonance production in central pp collisions at the CERN Omega


  A study of resonance production in central pp collisions is presented as a
function of several kinematical variables. In particular the difference in the
transverse momentum (dPT) of the exchanged particles shows that undisputed
qqbar mesons are suppressed at small dPT whereas glueball candidates are
enhanced and in addition, the azimuthal angle phi gives information on the
nature of the Pomeron.

</DOC>
<DOC>
<DOCNO> 9588 </DOCNO>
Effective Charge and Spin Hamiltonian for the Quarter-Filled Ladder


  An effective intra- and inter-ladder charge-spin hamiltonian for the
quarter-filled ladder compound $\alpha'$-NaV$_2$O$_5$ has been derived by using
the standard canonical transformation method. In the derivation, it is clear
that a finite inter-site Coulomb repulsion is needed to get a meaningful result
otherwise the perturbation becomes ill-defined. Various limiting cases
depending on the values of the model parameters have been analyzed in detail
and the effective exchange couplings are estimated. We find that the effective
intra-ladder exchange may become ferromagnetic for the case of zig-zag charge
ordering in a purely electronic model.
  We estimate the magnitude of the effective inter-rung Coulomb repulsion in a
ladder and find it to be about one-order of magnitude too small in order to
stabilize charge-ordering.

</DOC>
<DOC>
<DOCNO> 69001 </DOCNO>
pp Elastic Scattering at LHC and Signature of Chiral Phase Transition at


  A model of $pp$ and $\bar{p}p$ elastic scattering developed previously to
analyze ISR and SPS Collider data is extended to predict $pp$ elastic
differential cross section at LHC at c.m. energy of 14 TeV and momentum
transfer range $|t|=0$ - 10 GeV$^2$. Role of the gauged linear $\sigma$-model
as an underlying field theory model describing nucleon structure and elastic
scattering is discussed. Possibility of finding evidence of a chiral phase
transition at large $|t|$ in the proposed TOTEM project at LHC is pointed out.

</DOC>
<DOC>
<DOCNO> 100596 </DOCNO>
Marginal and Relevant Deformations of N=4 Field Theories and


  We study marginal and relevant supersymmetric deformations of the N=4
super-Yang-Mills theory in four dimensions. Our primary innovation is the
interpretation of the moduli spaces of vacua of these theories as
non-commutative spaces. The construction of these spaces relies on the
representation theory of the related quantum algebras, which are obtained from
F-term constraints. These field theories are dual to superstring theories
propagating on deformations of the AdS_5xS^5 geometry. We study D-branes
propagating in these vacua and introduce the appropriate notion of algebraic
geometry for non-commutative spaces. The resulting moduli spaces of D-branes
have several novel features. In particular, they may be interpreted as
symmetric products of non-commutative spaces. We show how mirror symmetry
between these deformed geometries and orbifold theories follows from T-duality.
Many features of the dual closed string theory may be identified within the
non-commutative algebra. In particular, we make progress towards understanding
the K-theory necessary for backgrounds where the Neveu-Schwarz antisymmetric
tensor of the string is turned on, and we shed light on some aspects of
discrete anomalies based on the non-commutative geometry.

</DOC>
<DOC>
<DOCNO> 10570 </DOCNO>
Phase structure of non-commutative scalar field theories


  We investigate the phase structure of non-commutative scalar field theories
and find evidence for ordered phases which break translation invariance. A
self-consistent one-loop analysis indicates that the transition into these
ordered phases is first order. The phase structure and the existence of scaling
limits provides an alternative to the structure of counter-terms in determining
the renormalizability of non-commutative field theories. On the basis of the
existence of a critical point in the closely related planar theory, we argue
that there are renormalizable interacting non-commutative scalar field theories
in dimensions two and above. We exhibit this renormalization explicitly in the
large $N$ limit of a non-commutative O(N) vector model.

</DOC>
<DOC>
<DOCNO> 80658 </DOCNO>
A formula with volumes of five tetrahedra and discrete curvature


  Given five points in a three-dimensional euclidean space, one can consider
five tetrahedra, using those points as vertices. We present a pentagon-like
formula containing the product of three volumes of those tetrahedra in its
l.h.s. and the product of the two remaining tetrahedron volumes in its r.h.s.,
as well as the derivative of the "discrete curvature" which arises when we
slightly deform our euclidean space.

</DOC>
<DOC>
<DOCNO> 121142 </DOCNO>
The Effects of Rotation on the Evolution of Rising Omega-loops in a


  We present three-dimensional MHD simulations of buoyant magnetic flux tubes
that rise through a stratified model convection zone in the presence of solar
rotation. The equations of MHD are solved in the anelastic approximation, and
the results are used to determine the effects of solar rotation on the dynamic
evolution an Omega-loop. We find that the Coriolis force significantly
suppresses the degree of fragmentation at the apex of the loop during its
ascent toward the photosphere. If the initial axial field strength of the tube
is reduced, then, in the absence of forces due to convective motions, the
degree of apex fragmentation is also reduced. We show that the Coriolis force
slows the rise of the tube, and induces a retrograde flow in both the
magnetized and unmagnetized plasma of an emerging active region.
Observationally, we predict that this flow will appear to originate at the
leading polarity, and will terminate at the trailing polarity.

</DOC>
<DOC>
<DOCNO> 39878 </DOCNO>
Can the beta decay of neutral kaons be observed?


  The rate of the beta decay of neutral kaons is calculated within the meson
dominance approach taking into account the relation between the KK\rho and
\pi\pi\rho coupling constants which follows from the vector meson dominance in
electromagnetic interactions and isospin symmetry. The decay rate transforms
into the following branching fraction summed over the charge states indicated:
B(K0L -> K+- e-+ nu)=(2.53+-0.10)x10^{-9}. The error is dominated by our
estimate of isospin violating effects. Experimental aspects of such a
measurement are discussed.

</DOC>
<DOC>
<DOCNO> 122829 </DOCNO>
Two-dimensional disk dynamos with vertical outflows into a halo


  We study the effects of vertical outflows on mean-field dynamos in disks.
These outflows could be due to thermal winds or magnetic buoyancy. We analyse
numerical solutions of the nonlinear mean-field dynamo equations using a
two-dimensional finite-difference model. Contrary to expectations, a modest
vertical velocity can enhance dynamo action. This can lead to super-exponential
growth of the magnetic field and to higher magnetic energies at saturation in
the nonlinear regime.

</DOC>
<DOC>
<DOCNO> 9264 </DOCNO>
On Density-Matrix Spectra for Two-Dimensional Quantum Systems


  For a two-dimensional system of coupled oscillators, the spectra of reduced
density matrices can be obtained analytically. This provides an example where
the features of these quantities, which are of central importance in numerical
studies using the DMRG method, can be seen.

</DOC>
<DOC>
<DOCNO> 12873 </DOCNO>
Magnetic Thomas-Fermi-Weizs\"acker model for quantum dots: a comparison


  The magnetic extension of the Thomas-Fermi-Weizs\"acker kinetic energy is
used within density-functional-theory to numerically obtain the ground state
densities and energies of two-dimensional quantum dots. The results are
thoroughly compared with the microscopic Kohn-Sham ones in order to assess the
validity of the semiclassical method. Circular as well as deformed systems are
considered.

</DOC>
<DOC>
<DOCNO> 119503 </DOCNO>
Statistical Properties of Narrow-Line Seyfert 1 galaxies


  The number of publications considering Narrow-Line Seyfert 1 galaxies has
increased dramatically in recent years. Especially after the launch of the
X-ray missions ROSAT and ASCA, Narrow-Line Seyfert 1s have become very popular.
In these proceedings I will give an overview of how they are distributed over
the electromagnetic spectrum. I will describe what we know about them at radio,
infrared, optical, and X-ray bands, and how they differ and how they are
similar to Broad-Line Seyfert 1s. Finally I will introduce a method to find
them with high probability.

</DOC>
<DOC>
<DOCNO> 150986 </DOCNO>
Deconfinement at the Argyres-Douglas point in SU(2) gauge theory with


  We consider chiral condensates in SU(2) gauge theory with broken N=2
supersymmetry. The matter sector contains an adjoint multiplet and one
fundamental flavor. Matter and gaugino condensates are determined by
integrating out the adjoint field. The only nonperturbative input is the
Affleck-Dine-Seiberg (ADS) superpotential generated by one instanton plus the
Konishi anomaly. These results are consistent with those obtained by the
`integrating in' procedure, including a reproduction of the Seiberg-Witten
curve from the ADS superpotential. We then calculate monopole, dyon, and charge
condensates using the Seiberg-Witten approach. We show that the monopole and
charge condensates vanish at the Argyres-Douglas point where the monopole and
charge vacua collide. We interpret this phenomenon as a deconfinement of
electric and magnetic charges at the Argyres-Douglas point.

</DOC>
<DOC>
<DOCNO> 102111 </DOCNO>
Some Properties of 3x3 Octonionic Hermitian Matrices with Non-Real


  We discuss our preliminary attempts to extend previous work on 2x2 Hermitian
octonionic matrices with non-real eigenvalues to the 3x3 case.

</DOC>
<DOC>
<DOCNO> 71159 </DOCNO>
Transition to resonance-rich matter in heavy ion collisions at RHIC


  The equilibration of hot and dense nuclear matter produced in the central
region in central Au+Au collisions at $\sqrt{s}=200$ AGeV is studied within the
microscopic transport model UrQMD. The pressure here becomes isotropic at $t
\approx 5$ fm/c. Within the next 15 fm/c the expansion of the matter proceeds
almost isentropically with the entropy per baryon ratio $S/A \approx 150$.
During this period the equation of state in the $(P,\epsilon)$-plane has a very
simple form, $P=0.15 \epsilon$. Comparison with the statistical model (SM) of
an ideal hadron gas reveals that the time of $\approx 20$ fm/$c$ may be too
short to attain the fully equilibrated state. Particularly, the fractions of
resonances are overpopulated in contrast to the SM values. The creation of such
a long-lived resonance-rich state slows down the relaxation to chemical
equilibrium and can be detected experimentally.

</DOC>
<DOC>
<DOCNO> 120133 </DOCNO>
Mass-to-Light Ratios of Groups and Clusters of Galaxies


  We constrain the mass-to-light ratios, gas mass fractions, baryon mass
fractions and the ratios of total to luminous mass for a sample of eight nearby
relaxed galaxy groups and clusters: A262, A426, A478, A1795, A2052, A2063,
A2199 and MKW4s. We use ASCA spatially resolved spectroscopic X-ray
observations and ROSAT PSPC images to constrain the total and gas masses of
these clusters. To measure cluster luminosities we use galaxy catalogs
resulting from the digitization and automated processing of the second
generation Palomar Sky Survey plates calibrated with CCD images in the
Gunn-Thuan g, r, and i bands.
  Under the assumption of hydrostatic equilibrium and spherical symmetry, we
can measure the total masses of clusters from their intra-cluster gas
temperature and density profiles. Spatially resolved ASCA spectra show that the
gas temperature decreases with increasing distance from the center. By
comparison, the assumption that the gas is isothermal results in an
underestimate of the total mass at small radii, and an overestimate at large
cluster radii.
  We have obtained luminosity functions for all clusters in our sample. After
correcting for background and foreground galaxies, we estimate the total
cluster luminosity using Schechter function fits to the galaxy catalogs. In the
three lowest redshift clusters where we can sample to fainter absolute
magnitudes, we have detected a flattening of the luminosity function at
intermediate magnitudes and a rise at the faint end. These clusters were fit
with a sum of two Schechter functions. The remaining clusters were well fit
with a single Schechter function.

</DOC>
<DOC>
<DOCNO> 84838 </DOCNO>
On supermatrix idempotent operator semigroups


  One-parameter semigroups of antitriangle idempotent supermatrices and
corresponding superoperator semigroups are introduced and investigated. It is
shown that $t$-linear idempotent superoperators and exponential superoperators
are mutually dual in some sense, and the first gives additional to exponential
solution to the initial Cauchy problem. The corresponding functional equation
and analog of resolvent are found for them. Differential and functional
equations for idempotent (super)operators are derived for their general $t$
power-type dependence.

</DOC>
<DOC>
<DOCNO> 69686 </DOCNO>
Three flavour neutrino oscillations in models with large extra


  The key challenges for models with large extra dimensions, posed by neutrino
physics are: first to understand why neutrino masses are small and second,
whether one can have a simultaneous explanation of all observed oscillation
phenomena. There exist models that answer the first challenge by using singlet
bulk neutrinos coupled to the standard model in the brane. Our goal in this
paper is to see to what extent the simplest versions of these models can answer
the second challenge. Our conclusion is that the minimal framework that has no
new physics beyond the above simple picture cannot simultaneously explain
solar, atmospheric and LSND data, whereas there are several ways that it can
accommodate the first two. This would suggest that confirmation of LSND data
would indicate the existence of new physics either in the brane or in extra
dimensions or both, if indeed it turns out that there are large extra
dimensions.

</DOC>
<DOC>
<DOCNO> 67849 </DOCNO>
Moduli constraints on primordial black holes


  The amount of late decaying massive particles (e.g., gravitinos, moduli)
produced in the evaporation of primordial black holes (PBHs) of mass
$\Mbh\la10^9 $g is calculated. Limits imposed by big-bang nucleosynthesis on
the abundance of these particles are used to constrain the initial PBH mass
fraction $\beta$ (ratio of PBH energy density to critical energy density at
formation), as: $\beta\la 5\times10^{-19} (\xp/6 10^{-3})^{-1} (\Mbh/10^9 {\rm
g})^{-1/2} (\bar{\Yp}/10^{-14})$; $\xp$ is the fraction of PBH luminosity going
into gravitinos or moduli, $\bar{\Yp}$ is the upper bound imposed by
nucleosynthesis on the number density to entropy density ratio of gravitinos or
moduli. This notably implies that such PBHs should never come to dominate the
cosmic energy density.

</DOC>
<DOC>
<DOCNO> 122239 </DOCNO>
TeV Gamma-Ray Absorption and the Intergalactic Infrared Background


  In this paper, I will take a synoptic approach to determining the
intergalactic infrared radiation field (IIRF). This approach draws on both the
multi-TeV gamma-ray observations and the infrared background observations and
relates them via the semi-empirical modelling method of Malkan and Stecker. I
discuss the evidence for an intergalactic infrared background obtained by an
analysis of the HEGRA observations of the high energy gamma-ray spectrum of Mrk
501 and from constraints from Mrk 421 deduced from the Whipple air Cherenkov
telescope results. I will show that this evidence is in accord with the
predictions made by Malkan and Stecker for the intergalactic infrared spectral
energy distribution produced by galaxies. The Malkan-Stecker predictions are
also in excellent agreement with mid- and far infrared galaxy counts. However,
there may be potential problems relating these predictions with the results of
the analysis of COBE-DIRBE far infrared data. The gamma-ray and COBE-DIRBE
observations may also need to be reconciled. I will discuss possible ways to
resolve this situation including a partial nullification of the $\gamma$-ray
absorption process which can hypothetically occur if Lorentz invariance is
broken.

</DOC>
<DOC>
<DOCNO> 101341 </DOCNO>
Compactness of the embedding operators for rough domains


  New classes of non-smooth bounded domains D, for which the embedding operator
from H^1(D) into L^2(D) is compact are introduced. Examples are given and
applications to scattering by rough obstacles are mentioned.

</DOC>
<DOC>
<DOCNO> 69973 </DOCNO>
Jets in Hadron Collisions


  We discuss recent progress and open questions in QCD jet physics, with
particular emphasis on two areas: jet definitions and jet substructure.

</DOC>
<DOC>
<DOCNO> 118415 </DOCNO>
Theory of solar luminosity variations


  The theory of stellar structure can be used to identify the most plausible
mechanisms for the irradiance variations associated with the solar cycle.
Changes in surface emissivity, i.e. the reduced cooling in spots and enhanced
emission by small scale magnetic fields, are the most effective mechanisms and
account for most of the observed variation. Helioseismology will soon be able
to test the consequences of changes in surface emissivity, and distinguish them
from other scenarios for irradiance variability.

</DOC>
<DOC>
<DOCNO> 120753 </DOCNO>
The Magnetohydrodynamic Kelvin-Helmholtz Instability: A


  We investigate through high resolution 3D simulations the nonlinear evolution
of compressible magnetohydrodynamic flows subject to the Kelvin-Helmholtz
instability. We confirm in 3D flows the conclusion from our 2D work that even
apparently weak magnetic fields embedded in Kelvin-Helmholtz unstable plasma
flows can be fundamentally important to nonlinear evolution of the instability.
In fact, that statement is strengthened in 3D by this work, because it shows
how field line bundles can be stretched and twisted in 3D as the quasi-2D Cat's
Eye vortex forms out of the hydrodynamical motions. In our simulations twisting
of the field may increase the maximum field strength by more than a factor of
two over the 2D effect. If, by these developments, the Alfv\'en Mach number of
flows around the Cat's Eye drops to unity or less, our simulations suggest
magnetic stresses will eventually destroy the Cat's Eye and cause the plasma
flow to self-organize into a relatively smooth and apparently stable flow that
retains memory of the original shear. For our flow configurations the regime in
3D for such reorganization is $4\lesssim M_{Ax} \lesssim 50$, expressed in
terms of the Alfv\'en Mach number of the original velocity transition and the
initial Alfv\'en speed projected to the flow plan. For weaker fields the
instability remains essentially hydrodynamic in early stages, and the Cat's Eye
is destroyed by the hydrodynamic secondary instabilities of a 3D nature. Then,
the flows evolve into chaotic structures that approach decaying isotropic
turbulence. In this stage, there is considerable enhancement to the magnetic
energy due to stretching, twisting, and turbulent amplification, which is
retained long afterwards. The magnetic energy eventually catches up to the
kinetic energy, and the nature of flows become magnetohydrodynamic.

</DOC>
<DOC>
<DOCNO> 152266 </DOCNO>
Regularization of Non-Linear Spinor Field Models by Discrete Symmetries


  We generalize a regularization method of Stumpf 1984 in the case of
non-linear spinor field models to fourth order theories and to non-scalar
interactions. The involved discrete symmetries can be connected with C,P,T
transformations.

</DOC>
<DOC>
<DOCNO> 13014 </DOCNO>
Heterogeneous condensation on several types of centers in dynamic


  A system of a metastable phase with several sorts of the heterogeneous
centers is considered. An analytical theory for the process of condensation in
such a system is constructed in dynamic conditions. The free energy of
formation of the critical embryo is assumed to be known in the macroscopic
approach as well as the energy of solvatation. The recurrent procedure of the
establishing of the characteristic times and lengths is presented. The
semiempirical method of the description of the period of essential formation of
new phase embryos on the heterogeneous centers of some sort is given.

</DOC>
<DOC>
<DOCNO> 85188 </DOCNO>
Conformal Black Hole Solutions of Axi-Dilaton Gravity in D-dimensions


  Static, spherically symmetric solutions of axi-dilaton gravity in $D$
dimensions is given in the Brans-Dicke frame for arbitrary values of the
Brans-Dicke constant $\omega$ and an axion-dilaton coupling parameter $k$. The
mass and the dilaton and axion charges are determined and a BPS bound is
derived. There exists a one parameter family of black hole solutions in the
scale invariant limit.

</DOC>
<DOC>
<DOCNO> 12686 </DOCNO>
Anomalous scaling in the Zhang model


  We apply the moment analysis technique to analyze large scale simulations of
the Zhang sandpile model. We find that this model shows different scaling
behavior depending on the update mechanism used. With the standard parallel
updating, the Zhang model violates the finite-size scaling hypothesis, and it
also appears to be incompatible with the more general multifractal scaling
form. This makes impossible its affiliation to any one of the known
universality classes of sandpile models. With sequential updating, it shows
scaling for the size and area distribution. The introduction of stochasticity
into the toppling rules of the parallel Zhang model leads to a scaling behavior
compatible with the Manna universality class.

</DOC>
<DOC>
<DOCNO> 11286 </DOCNO>
Transport Properties of Highly Aligned Polymer Light-Emitting-Diodes


  We investigate hole transport in polymer light-emitting-diodes in which the
emissive layer is made of liquid-crystalline polymer chains aligned
perpendicular to the direction of transport. Calculations of the current as a
function of time via a random-walk model show excellent qualitative agreement
with experiments conducted on electroluminescent polyfluorene demonstrating
non-dispersive hole transport. The current exhibits a constant plateau as the
charge carriers move with a time-independent drift velocity, followed by a long
tail when they reach the collecting electrode. Variation of the parameters
within the model allows the investigation of the transition from non-dispersive
to dispersive transport in highly aligned polymers. It turns out that large
inter-chain hopping is required for non-dispersive hole transport and that
structural disorder obstructs the propagation of holes through the polymer
film.

</DOC>
<DOC>
<DOCNO> 40163 </DOCNO>
Introduction to Superstring Theory


  These four lectures, addressed to an audience of graduate students in
experimental high energy physics, survey some of the basic concepts in string
theory. The purpose is to convey a general sense of what string theory is and
what it has achieved. Since the characteristic scale of string theory is
expected to be close to the Planck scale, the structure of strings probably
cannot be probed directly in accelerator experiments. The most accessible
experimental implication of superstring theory is supersymmetry at or below the
TeV scale.

</DOC>
<DOC>
<DOCNO> 83489 </DOCNO>
Available and Stabilizing 2-3 Trees


  Transient faults corrupt the content and organization of data structures. A
recovery technique dealing with such faults is stabilization, which guarantees,
following some number of operations on the data structure, that content of the
data structure is legitimate. Another notion of fault tolerance is
availability, which is the property that operations continue to be applied
during the period of recovery after a fault, and successful updates are not
lost while the data structure stabilizes to a legitimate state. The available,
stabilizing 2-3 tree supports find, insert, and delete operations, each with
O(lg n) complexity when the tree's state is legitimate and contains n items.
For an illegitimate state, these operations have O(lg K) complexity where K is
the maximum capacity of the tree. Within O(t) operations, the state of the tree
is guaranteed to be legitimate, where t is the number of nodes accessible via
some path from the tree's root at the initial state. This paper resolves, for
the first time, issues of dynamic allocation and pointer organization in a
stabilizing data structure.

</DOC>
<DOC>
<DOCNO> 118490 </DOCNO>
VSOP Observations of a Sub-Parsec Accretion Disk


  The physical conditions in the inner parsec of accretion disks believed to
orbit the central black holes in active galactic nuclei can be probed by
imaging the absorption of background radio emission by ionized gas in the disk.
We report high angular resolution observations of the nearby galaxy NGC 4261
which show evidence for free-free absorption by a thin, nearly edge-on disk at
several frequencies. The angular width, and probably the depth, of the
absorption appears to increase with decreasing frequency, as expected. Because
free-free absorption is much larger at lower frequencies, the longest possible
baselines are needed to provide adequate angular resolution; observing at
higher frequencies to improve resolution will not help.

</DOC>
<DOC>
<DOCNO> 102881 </DOCNO>
Reflection ideals and mappings between generic submanifolds in complex


  In this paper, we study formal mappings between smooth generic submanifolds
in multidimensional complex space and establish results on finite
determination, convergence and local biholomorphic and algebraic equivalence.
Our finite determination result gives sufficient conditions to guarantee that a
formal map as above is uniquely determined by its jet at a point of a
preassigned order. For real-analytic generic submanifolds, we prove convergence
of formal mappings under appropriate assumptions and also give natural
geometric conditions to assure that if two germs of such submanifolds are
formally equivalent, then they are necessarily biholomorphically equivalent. If
the submanifolds are moreover real-algebraic, we address the question of
deciding when biholomorphic equivalence implies algebraic equivalence. In
particular, we prove that if two real-algebraic hypersurfaces in $\C^N$ are
biholomorphically equivalent, then they are in fact algebraically equivalent.
All the results are first proved in the more general context of ``reflection
ideals" associated to formal mappings between formal as well as real-analytic
and real-algebraic manifolds.

</DOC>
<DOC>
<DOCNO> 39656 </DOCNO>
Signatures of massive sgoldstinos at e+e- colliders


  In supersymmetric extensions of the Standard Model with a very light
gravitino, the effective theory at the weak scale should contain not only the
goldstino G, but also its supersymmetric partners, the sgoldstinos. In the
simplest case, the goldstino is a gauge-singlet and its superpartners are two
neutral spin-0 particles, S and P. We study possible signals of massive
sgoldstinos at e+e- colliders, focusing on those that are most relevant at LEP
energies. We show that the LEP constraints on e+e- => photon+S (photon+P), Z+S
(Z+P) or e+e-S (e+e-P), followed by S (P) decaying into two gluon jets, can
lead to stringent combined bounds on the gravitino and sgoldstino masses.

</DOC>
<DOC>
<DOCNO> 178605 </DOCNO>
Nucleon Resonance Transition Couplings to Vector Mesons


  Recent heavy ion experiments indicate modifications of the $\rho-$meson mass
in medium. In the CERES experiments $\rho-$mesons are produced at $\sim$
normal nuclear matter density, where hadrons are more appropriate constituents
than quarks. A collective "nuclear $\rho$", in which every nucleon is excited
to the N(1520) state, with equal amplitude, enters in this description. At the
higher densities reached by future experiments constituent quarks become the
appropriate variables. Here the $\rho$ and $\omega$ transition couplings to the
nucleon resonances up to 1700 MeV, including the N(1520), are derived by means
of the chiral quark model. The relevant coupling constants are expressed in
terms of the corresponding vector coupling constants to nucleons. The quality
of the model relations is tested by a calculation of the corresponding
pion-resonance coupling constants, which are known from the empirical pion
decay widths.

</DOC>
<DOC>
<DOCNO> 70764 </DOCNO>
$\rho$-Meson wave functions from nonlocal light-cone operators with


  We introduce chiral-even and chiral-odd meson wave functions as
vacuum-to-meson matrix elements of bilocal quark operators with well-defined
(geometric) twist. Thereby, we achieve a Lorentz invariant classification of
these distributions which differ from the conventional ones by explicitly
taking into account the trace terms. The relations between conventional and new
wave functions are given.

</DOC>
<DOC>
<DOCNO> 10079 </DOCNO>
Reflectivity Anisotropy Spectra of Cu- and Ag- (110) surfaces from {\it


  We are able to disentagle the effects of the intraband and interband parts of
the bulk dielectric function on the bare dielectric anisotropy of the surface.
We show how the position, sign and amplitude of the structures observed in such
spectra depend on the above quantities. The lineshape of all the calculated
structures agree very well with the ones observed experimentally for samples
treated by suitable surface cleaning. In particular, we reproduce the observed
single peak structure of Ag at high energy, found to represent a state of the
clean surface different from the one giving the originally observed double peak
structure. This results is not reproduced by the 'local field' model.

</DOC>
<DOC>
<DOCNO> 118451 </DOCNO>
Supernovae


  The properties of supernovae (SNe) are reviewed. It is shown that the
observed characteristics of the morphological classes of SNe (types Ia, Ib/c,
II) can be explained in terms of two basic explosion mechanisms, i.e. core
collapse of massive stars and thermonuclear explosion of low/moderate mass
stars.
  The study of SNe can provide valuable insight in the late phases of the
evolution of their progenitors and, therefore, can constrain the theory of
stellar evolution quite tightly.
  Also, bright SNe of type Ia can be used to probe the Universe up to high
redshifts, allowing us to measure cosmological constants and to gain valuable
information on the formation and evolution of galaxies.
  The case of SN 1987A is discussed in some detail: it appears that in this
event a number of predictions were astonishingly well verified but still many
aspects were completely at variance with "common wisdom" expectations,
indicating that the SN phenomenon is still not fully understood.

</DOC>
<DOC>
<DOCNO> 120907 </DOCNO>
The Local Group


  Local Group galaxies such as the Milky Way, the Magellanic Clouds, and M31
are being used by a number of international collaborations to search for
microlensing events. Type and number of detections place constraints on dark
matter and the stellar populations within and along the line of sight to these
galaxies. In this review I briefly discuss the stellar populations,
evolutionary histories, and other properties of different types of Local Group
galaxies as well as constraints on the dark matter content of these galaxies.
Particular emphasis is placed on the dwarf companions of the spiral galaxies in
the Local Group.

</DOC>
<DOC>
<DOCNO> 68516 </DOCNO>
From Constituent Quark to Hadron Structure in the Next-to-Leading Order:


  We calculate the partonic structure of constituent quark in the
Next-to-Leading Order for the first time. The structure of any hadron can be
obtained thereafter using a convolution method. Such a procedure is used to
generate the structure function of proton and pion in NLO. It is shown that
while the constituent quark structure is generated purely perturbatively and
accounts to most part of the hadronic structure, there is a few percent
contributions coming from the nonperturbative sector in the hadronic structure.
This contribution plays the key role in explaining the SU(2) symmetry breaking
of the nucleon sea and the observed violation of Gottfried sum rule. These
effects are calculated. Excellent agreement with data in a wide range of
$x=[10^{-6}, 1]$ and $Q^{2}=[0.5, 5000]$ $GeV^{2}$ is reached for proton
structure function. We have also calculated Pion structure and compared it with
the existing data. Again nice agreement is achieved.

</DOC>
<DOC>
<DOCNO> 71192 </DOCNO>
Searching for New Physics via CP Violation in B -> pi pi


  It is well known that one can use B -> pi pi decays to probe the CP-violating
phase \alpha. In this paper we show that these same decays can be used to
search for new physics. This is done by comparing two weak phases which are
equal in the standard model: the phase of the t-quark contribution to the b ->
d penguin amplitude, and the phase of Bd-Bd(bar) mixing. In order to make such
a comparison, we require one piece of theoretical input, which we take to be a
prediction for |P/T|, the relative size of the penguin and tree contributions
to Bd -> pi^+ pi^-. If independent knowledge of \alpha is available, the decay
Bd(t) -> pi^+ pi^- alone can be used to search for new physics. If a full
isospin analysis can be done, then new physics can be found solely through
measurements of B -> pi pi decays. The most promising scenario occurs when the
isospin analysis can be combined with independent knowledge of \alpha. In all
cases, the prospects for detecting new physics in B -> pi pi decays can be
greatly improved with the help of additional measurements which will remove
discrete ambiguities.

</DOC>
<DOC>
<DOCNO> 151271 </DOCNO>
Macroscopical matter derived from Quantum Field Theory


  We develop the WKB expansion to relate Quantum Field Theory variables with
those describing macroscopical matter. We find that, up to the first quantum
correction, free scalar fields correspond to perfect fluids with pressure. We
also find the law of motion for the associated particles which takes into
account deviations from the classical trajectories, showing that they do not
follow unaccelerated straight line trajectories.
  Keywords: Quantum Field Theory, Fluid dynamics.
  PACS number (s): 11.10.-z, 03.40.Gc

</DOC>
<DOC>
<DOCNO> 8887 </DOCNO>
Output spectrum of a detector measuring quantum oscillations


  We consider a two-level quantum system (qubit) which is continuously measured
by a detector and calculate the spectral density of the detector output. In the
weakly coupled case the spectrum exhibits a moderate peak at the frequency of
quantum oscillations and a Lorentzian-shape increase of the detector noise at
low frequency. With increasing coupling the spectrum transforms into a single
Lorentzian corresponding to random jumps between two states. We prove that the
Bayesian formalism for the selective evolution of the density matrix gives the
same spectrum as the conventional master equation approach, despite the
significant difference in interpretation. The effects of the detector
nonideality and the finite-temperature environment are also discussed.

</DOC>
<DOC>
<DOCNO> 68398 </DOCNO>
Physics at e+e- Linear Colliders


  I discuss the motivation and physics potential of an electron-positron linear
collider with a center-of-mass energy at the 1 TeV scale, in light of what we
may expect to learn with the LHC. The comparison is illustrated with examples
drawn from Higgs physics, top quark physics, and the search for large extra
spacetime dimensions.

</DOC>
<DOC>
<DOCNO> 12888 </DOCNO>
Soluble two-species diffusion-limited Models in arbitrary dimensions


  A class of two-species ({\it three-states}) bimolecular diffusion-limited
models of classical particles with hard-core reacting and diffusing in a
hypercubic lattice of arbitrary dimension is investigated. The manifolds on
which the equations of motion of the correlation functions close, are
determined explicitly. This property allows to solve for the density and the
two-point (two-time) correlation functions in arbitrary dimension for both, a
translation invariant class and another one where translation invariance is
broken. Systems with correlated as well as uncorrelated, yet random initial
states can also be treated exactly by this approach. We discuss the asymptotic
behavior of density and correlation functions in the various cases. The
dynamics studied is very rich.

</DOC>
<DOC>
<DOCNO> 10499 </DOCNO>
Mesoscopic and Microscopic Phase Segregation in Manganese Perovskites


  Mesoscopic (500-2000 Angstrom) and microscopic (5-20 Angstrom) phase
segregation with temperature and magnetic field was studied in the model
manganite Pr0.7Ca0.3MnO3 by high-resolution neutron diffraction and inelastic
neutron scattering. Intra-granular strain-driven mesoscopic segregation between
two insulating phases, one of which is charge ordered (CO), sets in below the
CO temperature in zero field. The CO phase orders antiferromagnetically, while
the other insulating phase shows spin-glass behavior. After field-induced
metallization, the CO phase coexists with a ferromagnetic metallic phase.

</DOC>
<DOC>
<DOCNO> 13801 </DOCNO>
Thermodynamic properties of a small superconducting grain


  The reduced BCS Hamiltonian for a metallic grain with a finite number of
electrons is considered. The crossover between the ultrasmall regime, in which
the level spacing, $d$, is larger than the bulk superconducting gap, $\Delta$,
and the small regime, where $\Delta \gtrsim d$, is investigated analytically
and numerically. The condensation energy, spin magnetization and tunneling peak
spectrum are calculated analytically in the ultrasmall regime, using an
approximation controlled by $1/\ln N$ as small parameter, where $N$ is the
number of interacting electron pairs. The condensation energy in this regime is
perturbative in the coupling constant $\lambda$, and is proportional to $d N
\lambda^2 = \lambda^2 \omega_D$. We find that also in a large regime with
$\Delta>d$, in which pairing correlations are already rather well developed,
the perturbative part of the condensation energy is larger than the singular,
BCS, part. The condition for the condensation energy to be well approximated by
the BCS result is found to be roughly $\Delta > \sqrt{d \omega_D}$. We show how
the condensation energy can, in principle, be extracted from a measurement of
the spin magnetization curve, and find a re-entrant susceptibility at zero
temperature as a function of magnetic field, which can serve as a sensitive
probe for the existence of superconducting correlations in ultrasmall grains.
Numerical results are presented which suggest that in the large $N$ limit the
1/N correction to the BCS result for the condensation energy is larger than
$\Delta$.

</DOC>
<DOC>
<DOCNO> 169626 </DOCNO>
Quantum mechanics and the continuum problem(II)


  In one-dimensional case, it is shown that the basic principles of quantum
mechanics are properties of the set of intermediate cardinality.

</DOC>
<DOC>
<DOCNO> 102309 </DOCNO>
L^2 curvature and volume renormalization of AHE metrics on 4-manifolds


  This paper relates the boundary term in the Chern-Gauss-Bonnet formula on
4-manifolds M with the renormalized volume V, as defined in the AdS/CFT
correspondence, for asymptotically hyperbolic Einstein metrics on M. In
addition, we compute and discuss the differential or variation dV of V, or
equivalently the variation of the L^2 norm of the Weyl curvature, on the space
of such Einstein metrics.

</DOC>
<DOC>
<DOCNO> 151719 </DOCNO>
Warped Compactification with an Abelian Gauge Theory


  We investigate warped compactification with an abelian gauge theory in six
dimensions. The vanishing cosmological constant in four dimensions can
generically be realized with a regular metric even in a 3-brane background
without fine tuning of couplings.

</DOC>
<DOC>
<DOCNO> 14151 </DOCNO>
Phase Diagram of a 2D Vertex Model


  Phase diagram of a symmetric vertex model which allows 7 vertex
configurations is obtained by use of the corner transfer matrix renormalization
group (CTMRG), which is a variant of the density matrix renormalization group
(DMRG). The critical indices of this model are identified as $\beta = 1/8$ and
$\alpha = 0$.

</DOC>
<DOC>
<DOCNO> 119962 </DOCNO>
Temperature and Density Gradients Across the Nucleus of M82


  This paper presents 12CO J=3-2, 13CO J=3-2, C18O J=3-2, and 13CO J=2-1
spectra of the irregular starburst galaxy M82 taken with the 15 m James Clerk
Maxwell Telescope. All maps exhibit a double peaked morphology, despite
evidence that the higher J transitions are optically thick. This morphology
suggests that the double peaked structure is not the result of an edge-on torus
of molecular gas as is commonly assumed. We observe line ratio gradients that
can best be explained by a temperature gradient increasing from NE to SW in
conjunction with a density gradient that increases in the opposite sense. These
gradients may have been caused by the interaction with M81, resulting in
increased star formation that both heats and depletes the molecular gas in the
SW lobe of M82.

</DOC>
<DOC>
<DOCNO> 119091 </DOCNO>
Galaxy Evolution at 0 < z < 2 from the NICMOS HDF-North


  We have carried out a deep infrared imaging survey (1.1um and 1.6um) of the
Hubble Deep Field North (HDF-N) using NICMOS on board the Hubble Space
Telescope. The combined WFPC2+NICMOS data set lets us study galaxy
morphologies, colors and luminosities at common rest frame wavelengths over a
broad range of redshifts, e.g., in the V-band out to z=2. Here, I illustrate
some applications of this data set for studying the evolution of giant
galaxies, on and off the Hubble Sequence. Large, relatively ordinary spiral
galaxies are found out to at least z=~1.25. Morphological irregularities seen
in many distant HDF galaxies tend to persist from ultraviolet through optical
rest frame wavelengths, suggesting that these are genuinely peculiar,
structurally disturbed systems. Red giant ellipticals are found out to
(photometric) redshifts z=~1.8, implying that some such galaxies probably
formed the bulk of their stars at z_f>~4. However, there are also bluer early
type galaxies at z>0.5, which may have experienced extended star formation
histories. Finally, there appears to be a substantial deficit of high
luminosity galaxies of all types at 1.4<~z<2 compared to lower redshifts.
However, this result must be considered with caution given the small volume of
the HDF, its susceptibility to line-of-sight clustering variations, and the
heavy reliance on photometric redshifts at z>~1.4.

</DOC>
<DOC>
<DOCNO> 83485 </DOCNO>
Rewriting Calculus: Foundations and Applications


  This thesis is devoted to the study of a calculus that describes the
application of conditional rewriting rules and the obtained results at the same
level of representation. We introduce the rewriting calculus, also called the
rho-calculus, which generalizes the first order term rewriting and
lambda-calculus, and makes possible the representation of the non-determinism.
In our approach the abstraction operator as well as the application operator
are objects of calculus. The result of a reduction in the rewriting calculus is
either an empty set representing the application failure, or a singleton
representing a deterministic result, or a set having several elements
representing a not-deterministic choice of results.
  In this thesis we concentrate on the properties of the rewriting calculus
where a syntactic matching is used in order to bind the variables to their
current values. We define evaluation strategies ensuring the confluence of the
calculus and we show that these strategies become trivial for restrictions of
the general rewriting calculus to simpler calculi like the lambda-calculus. The
rewriting calculus is not terminating in the untyped case but the strong
normalization is obtained for the simply typed calculus.
  In the rewriting calculus extended with an operator allowing to test the
application failure we define terms representing innermost and outermost
normalizations with respect to a set of rewriting rules. By using these terms,
we obtain a natural and concise description of the conditional rewriting.
Finally, starting from the representation of the conditional rewriting rules,
we show how the rewriting calculus can be used to give a semantics to ELAN, a
language based on the application of rewriting rules controlled by strategies.

</DOC>
<DOC>
<DOCNO> 10351 </DOCNO>
Antiferromagnetism, Stripes, and Superconductivity in the t-J Model with


  We study mean-field phases of the t-J model with long-range Coulomb
interaction. In the order of increasing doping density we find a classical
antiferromagnet, charge and spin stripes, and a uniform d-wave superconductor,
at the realistic doping parameters. Both in-phase and anti-phase stripes exist
as metastable configurations, but the in-phase stripes have a slightly lower
energy. The dependence of the stripe width and the inter-stripe spacing on the
doping is examined. Effects of fluctuations around the mean-field states are
discussed.

</DOC>
<DOC>
<DOCNO> 119267 </DOCNO>
Hyperstars: Phase Transition to (Meta)-Stable Hyperonic Matter in


  Recent progress in the understanding of the high density phase of neutron
stars advances the view that a substantial fraction of the matter consists of
hyperons. The possible impacts of a highly attractive interaction between
hyperons on the properties of compact stars is investigated. We find that the
equation of state can exhibit a phase transition at large hyperon contents
which gives rise to neutron star properties similar to the ones proposed for
the deconfinement transition. The corresponding compact stars can have rather
small radii of R=8 km.

</DOC>
<DOC>
<DOCNO> 122786 </DOCNO>
Electron-Positron Pair Cascades and Precursors in Gamma-Ray Bursts


  Gamma-ray burst sources with a high luminosity can produce electron-positron
pair cascades in their environment as a result of back-scattering of a seed
fraction of their original hard spectrum. The resulting spectral modifications
offer the possibility of diagnosing not only the compactness parameter of the
gamma-ray emitting region but also the baryonic density of the environment
external to the burst.

</DOC>
<DOC>
<DOCNO> 70703 </DOCNO>
The Overlap Representation of Skewed Quark and Gluon Distributions


  Within the framework of light-cone quantisation we derive the complete and
exact overlap representation of skewed parton distributions for unpolarised and
polarised quarks and gluons. Symmetry properties and phenomenological
applications are discussed.

</DOC>
<DOC>
<DOCNO> 9778 </DOCNO>
Variational wave functions of a vortex in cyclotron motion


  In two dimensions the microscopic theory, which provides a basis for the
naive analogy between a quantized vortex in a superfluid and an electron in an
uniform magnetic field, is presented. A one-to-one correspondence between the
rotational states of a vortex in a cylinder and the cyclotron states of an
electron in the central gauge is found. Like the Landau levels of an electron,
the energy levels of a vortex are highly degenerate. However, the gap between
two adjacent energy levels does not only depend on the quantized circulation,
but also increases with the energy, and scales with the size of the vortex.

</DOC>
<DOC>
<DOCNO> 70626 </DOCNO>
Twisting Lightlike Solutions of the Kerr-Schild Class


  Using a complex representation of the Debney-Kerr-Schild (DKS) solutions and
the Kerr theorem we give a method to construct boosted Kerr geometries. In the
ultrarelativistic case this method yelds twisting solutions having, contrary to
the known pp-wave limiting solutions, a non-zero value of the total angular
momentum. The solutions show that twist plays a crucial role in removing
singularity and smoothing shock wave in the ultrarelativistic limit. Two
different physical situations are discussed.

</DOC>
<DOC>
<DOCNO> 7770 </DOCNO>
Collective Modes of Quantum Hall Stripes


  The collective modes of striped phases in a quantum Hall system are computed
using the time-dependent Hartree-Fock approximation. Uniform stripe phases are
shown to be unstable to the formation of modulations along the stripes, so that
within the Hartree-Fock approximation the groundstate is a stripe crystal. Such
crystalline states are generically gapped at any finite wavevector; however, in
the quantum Hall system the interactions of modulations among different stripes
is found to be remarkably weak, leading to an infinite collection of collective
modes with immeasurably small gaps. The resulting long wavelength behavior is
derivable from an elastic theory for smectic liquid crystals. Collective modes
for the phonon branch are computed throughout the Brillouin zone, as are spin
wave and magnetoplasmon modes. A soft mode in the phonon spectrum is identified
for partial filling factors sufficiently far from 1/2, indicating a second
order phase transition. The modes contain several other signatures that should
be experimentally observable.

</DOC>
<DOC>
<DOCNO> 117031 </DOCNO>
Wave packet evolution approach to ionization of hydrogen molecular ion


  The multiply differential cross section of the ionization of hydrogen
molecular ion by fast electron impact is calculated by a direct approach, which
involves the reduction of the initial 6D Schr\"{o}dinger equation to a 3D
evolution problem followed by the modeling of the wave packet dynamics. This
approach avoids the use of stationary Coulomb two-centre functions of the
continuous spectrum of the ejected electron which demands cumbersome
calculations. The results obtained, after verification of the procedure in the
case atomic hydrogen, reveal interesting mechanisms in the case of small
scattering angles.

</DOC>
<DOC>
<DOCNO> 72166 </DOCNO>
Key Issues in Hadronic Physics


  A group of fifty physicists met in Duck, NC, Nov. 6-9 to discuss the current
status and future goals of hadronic physics. The main purpose of the meeting
was to define the field by identifying its key issues, challenges, and
opportunities. The conclusions, incorporating considerable input from the
community at large, are presented in this white paper.

</DOC>
<DOC>
<DOCNO> 178921 </DOCNO>
Shell model studies of neutron rich nuclei


  We discuss the present status of the description of the structure of the very
neutron rich nuclei, in the framework of modern large scale shell model
calculations. Particular attention is paid to the interaction related issues,
as well as to the problems of the shell model approach at the neutron drip
line. We present detailed results for nuclei around N=20 and, more briefly, we
discuss some salient features of the regions close to N=8, 28 and 40. We show
that most experimental features can be understood in a shell model context.

</DOC>
<DOC>
<DOCNO> 7883 </DOCNO>
Boundary and finite-size effects in small magnetic systems


  We study the effect of free boundaries in finite magnetic systems of cubic
shape on the field and temperature dependence of the magnetization within the
isotropic model of D-component spin vectors in the limit D \to \infty. This
model is described by a closed system of equations and captures the
Goldstone-mode effects such as global rotation of the magnetic moment and
spin-wave fluctuations. We have obtained an exact relation between the
intrinsic (short-range) magnetization M = M(H,T) of the system and the
supermagnetization m = m(H,T) which is induced by the field. We have shown,
analytically at low temperatures and fields and numerically in a wide range of
these parameters, that boundary effects leading to the decrease of M with
respect to the bulk value are stronger than the finite-size effects making a
positive contribution to M. The inhomogeneities of the magnetization caused by
the boundaries are long ranged and extend far into the depth of the system.

</DOC>
<DOC>
<DOCNO> 170424 </DOCNO>
Experimental NMR Realization of A Generalized Quantum Search Algorithm


  A generalized quantum search algorithm, where phase inversions for the marked
state and the prepared state are replaced by $\pi/2$ phase rotations, is
realized in a 2-qubit NMR heteronuclear system. The quantum algorithm searches
a marked state with a smaller step compared to standard Grover algorithm. Phase
matching requirement in quantum searching is demonstrated by comparing it with
another generalized algorithm where the two phase rotations are $\pi/2$ and
$3\pi/2$ respectively. Pulse sequences which include non 90 degree pulses are
given.

</DOC>
<DOC>
<DOCNO> 12746 </DOCNO>
Theory on Superconducting Transition from Pseudogap State


  The anomalous properties of High-$T_{{\rm c}}$ cuprates are investigated both
in the normal state and in the superconducting state. In particular, we pay
atte ntion to the pseudogap in the normal state and the phase transition from
the pse udogap state to the superconducting state.
  The pseudogap phenomena observed in cuprates are naturally understood as a
precursor of the strong coupling superconductivity. We have previously show n
by using the self-consistent T-matrix calculation that the pseudogap is a resu
lt of the strong superconducting fluctuations which are accompanied by the
stron g coupling superconductivity in quasi-two dimensional systems [J. Phys.
Soc. Jpn . {\bf68} (1999) 2999.].
  We extend the scenario to the superconducting state. The close relation
between the pseudogap state and the superconducting state is pointed out. Once
t he superconducting phase transition occurs, the superconducting order
parameter rapidly grows rather than the result of BCS theory. With the rapid
growth of the order parameter, the gap structure becomes sharp, while it is
remarkably broad in the pseudogap state. The characteristic energy scale of the
gap does not chan ge. These results well explain the phase transition observed
in the spectroscopi c measurements.
 Further, we calculate the magnetic and transport properties which show the
pseu dogap phenomena. The comprehensive understanding of the NMR, the neutron
scatter ing, the optical conductivity and the London penetration depth is
obtained both in the pseudogap state and in the superconducting state.

</DOC>
<DOC>
<DOCNO> 68022 </DOCNO>
Gamma-Ray Bursts, Cosmic-Rays and Neutrinos


  The gamma-ray burst (GRB) model for production of ultra-high-energy
cosmic-rays (UHECRs) is based on the hypothesis that GRBs arise from the
dissipation of the kinetic energy of relativistic fireballs at cosmological
distances. Recent GRB afterglow observations support the validity of this
hypothesis and provide quantitative support for the model. The inferred
physical fireball parameters imply that protons may be accelerated to >10^20
eV, and the inferred GRB energy generation rate is similar to that required to
account for the observed flux of UHECRs.
  Strong suppression of UHECR flux is expected in this model above 10^19.7 eV,
due to proton interaction with CMB photons. Strong deviations from model flux
derived under the assumption of uniform source distribution is expected above
10^20 eV, due to source clustering. The flux above 10^20.5 eV is expected to be
dominated by few, narrow spectrum sources. While model predictions can not be
tested (with high confidence level) at present, the predicted signatures should
be observed with the planned Auger and Telescope-Array UHECR detectors.
  A natural consequence of the GRB model of UHECR production is the conversion
of a large fraction, ~10%, of the fireball energy to accompanying burst of
\~10^14 eV and ~10^18 eV neutrinos. A km^2 neutrino detector would observe
several tens of events per year correlated with GRBs, and test for neutrino
properties (e.g. flavor oscillations, for which upward moving tau's would be a
unique signature, and coupling to gravity) with an accuracy many orders of
magnitude better than is currently possible.

</DOC>
<DOC>
<DOCNO> 102777 </DOCNO>
Invitation to higher local fields, Part I, section 12: Two types of


  This work sketches the author classification of complete discrete valuation
fields K of characteristic 0 with residue field of characteristic p into two
classes depending on the behaviour of the torsion part of a differential
module. For each of these classes, the quotient filtration of the Milnor
K-groups of K is characterized for all sufficiently large members of the
filtration, as a quotient of differential modules. For a higher local field the
previous result and higher local class field theory imply certain restrictions
on types of cyclic extensions of the field of sufficiently large degree.

</DOC>
<DOC>
<DOCNO> 10185 </DOCNO>
Reconstructed Rough Phases During Surface Growth


  Flat surface phases are unstable during growth and known to become rough.
This does not exclude the possibility that surface reconstruction order
persists in rough growing surfaces, in analogy with so-called equilibrium
reconstructed rough phases. We investigate this in the context of KPZ type
dynamics, using the restricted solid on solid model with negative mono-atomic
step energies. Long range reconstruction order is strictly speaking absent in
the thermodynamic limit, but the reconstruction domain walls become trapped at
surface ridge lines, and the reconstruction order parameter fluctuates
critically with the KPZ dynamic exponent at finite but large length scales.

</DOC>
<DOC>
<DOCNO> 122972 </DOCNO>
Dark Matter and Large Scale Structure


  A review of the study of dark matter and large scale structure of the
Universe at Tartu Observatory is given. Tartu astronomers have participated in
this development, starting from Ernst "Opik and Grigori Kuzmin, and continuing
with the present generation of astronomers. Our goal was to understand better
the structure, origin and evolution of the Universe.

</DOC>
<DOC>
<DOCNO> 85663 </DOCNO>
Anisotropic Stars: Exact Solutions


  We study the effects of anisotropic pressure on the properties of spherically
symmetric, gravitationally bound objects. We consider the full general
relativistic treatment of this problem and obtain exact solutions for various
form of equations of state connecting the radial and tangential pressures. It
is shown that pressure anisotropy can have significant effects on the structure
and properties of stellar objects. In particular, the maximum value of 2M/R can
approach unity (2M/R < 8/9 for isotropic objects) and the surface redshift can
be arbitrarily large.

</DOC>
<DOC>
<DOCNO> 10883 </DOCNO>
Lectures on Non Perturbative Field Theory and Quantum Impurity Problems:


  These are notes of lectures given at The NATO Advanced Study Institute/EC
Summer School on ``New Theoretical Approaches to Strongly Correlated Systems''
(Newton Institute, April 2000). They are a sequel to the notes I wrote two
years ago for the Summer School ``Topological Aspects of Low Dimensional
Systems'', (Les Houches, July 1998). In this second part, I review the
form-factors technique and its extension to massless quantum field theories. I
then discuss the calculation of correlators in integrable quantum impurity
problems, with special emphasis on point contact tunneling in the fractional
quantum Hall effect, and the two-state problem of dissipative quantum
mechanics.

</DOC>
<DOC>
<DOCNO> 122513 </DOCNO>
Galaxies: From Kinematics to Dynamics


  These lectures are intended to provide an introduction to the rich interplay
between N-body simulations and stellar-kinematic observations of galaxies. The
first section describes the kinematic properties of galaxies that are
accessible to observation, and gives a brief introduction to the stellar
dynamics that one might wish to infer from such observations. In the next
section, the use of N-body simulations in the study of galaxy dynamics is
placed in its historical context. The next two sections provide case studies of
the stellar-dynamical properties of elliptical and disk galaxies where N-body
simulations have been used to explain kinematic data, to test new analysis
techniques, and to motivate further observations. The final section contains
some speculation as to how the symbiotic relation between observations and
N-body simulations may develop in future studies of galaxy dynamics.

</DOC>
<DOC>
<DOCNO> 8993 </DOCNO>
Opening an energy gap in an electron double layer system at integer


  We employ magnetocapacitance measurements to study the spectrum of a double
layer system with gate-voltage-tuned electron density distributions in tilted
magnetic fields. For the dissipative state in normal magnetic fields at filling
factor $\nu=3$ and 4, a parallel magnetic field component is found to give rise
to opening a gap at the Fermi level. We account for the effect in terms of
parallel-field-caused orthogonality breaking of the Landau wave functions with
different quantum numbers for two subbands.

</DOC>
<DOC>
<DOCNO> 102034 </DOCNO>
Intertwining operators and modular invariance


  We extend the modular invariance property of the trace functions of vertex
operator algebra on the set of irreducible modules (Zhu's theory) to the case
of trace functions of intertwining operators.

</DOC>
<DOC>
<DOCNO> 118380 </DOCNO>
Design Considerations for Large Detector Arrays on Submillimeter-wave


  The emerging technology of large (~ 10,000 pixel) submillimeter-wave
bolometer arrays presents a novel optical design problem---how can such arrays
be fed by diffraction-limited telescope optics where the primary mirror is less
than 100,000 wavelengths in diameter? Standard Cassegrain designs for
radiotelescope optics exhibit focal surface curvature so large that detectors
cannot be placed more than 25 beam diameters from the central ray. The problem
is worse for Ritchey-Cretien designs, because these minimize coma while
increasing field curvature. Classical aberrations, including coma, are usually
dominated by diffraction in submillimeter-wave single dish telescopes. The
telescope designer must consider (1) diffraction, (2) aberration, (3) curvature
of field, (4) cross-polarization, (5) internal reflections, (6) the effect of
blockages, (7) means of beam chopping on- and off-source, (8) gravitational and
thermal deformations of the primary mirror, (9) the physical mounting of large
detector packages, and (10) the effect of gravity and (11) vibration on those
detectors. Simultaneous optimization of these considerations in the case of
large detector arrays leads to telescopes that differ considerably from
standard radiotelescope designs. Offset optics provide flexibility for mounting
detectors, while eliminating blockage and internal reflections. Aberrations and
cross-polarization can be the same as on-axis designs having the same diameter
and focal length. Trade-offs include the complication of primary mirror
homology and an increase in overall cost. A dramatic increase in usable field
of view can be achieved using shaped optics. Solutions having one to six
mirrors will be discussed, including a possible six-mirror design for the
proposed South Pole 10m telescope.

</DOC>
<DOC>
<DOCNO> 120427 </DOCNO>
Face-on galaxies NGC 524 and NGC 6340: chemically decoupled nuclei and


  Central regions of the early-type disk galaxies NGC 524 and NGC 6340 have
been investigated with the Multi-Pupil Field Spectrograph at the 6m telescope
of the Special Astrophysical Observatory of the Russian Academy of Sciences. I
confirm the existence of chemically distinct stellar nuclei in these galaxies
which have been claimed earlier. The metallicity differences which are found
between the nuclei and the bulges, 0.5 - 1.0 kpc from the centers, reach 0.5 -
0.6 dex. Both nuclei are magnesium overabundant, but the bulges have different
magnesium-to-iron ratios: it is solar in NGC 6340 and the same as the nuclear
one in NGC 524. The kinematical and morphological analyses reveal the existence
of inclined central disks in these galaxies. In NGC 524 the central disk
consists of stars, dust, and ionized gas; its extension may be as large as up
to R=3 kpc, and it is inclined by more than 20 deg to the global galactic
plane. In NGC 6340 only a gaseous polar disk with the radius less than 500 pc
is detected.

</DOC>
<DOC>
<DOCNO> 8214 </DOCNO>
Super-radiant light scattering from trapped Bose Einstein condensates


  We propose a new formulation for atomic side mode dynamics from super-radiant
light scattering of trapped atoms. A detailed analysis of the recently observed
super-radiant light scattering from trapped bose gases [S. Inouye {\it et al.},
Science {\bf 285}, 571 (1999)] is presented. We find that scattered light
intensity can exhibit both oscillatory and exponential growth behaviors
depending on densities, pump pulse characteristics, temperatures, and geometric
shapes of trapped gas samples. The total photon scattering rate as well as the
accompanied matter wave amplification depends explicitly on atom number
fluctuations in the condensate. Our formulation allows for natural and
transparent interpretations of subtle features in the MIT data, and provides
numerical simulations in good agreement with all aspects of the experimental
observations.

</DOC>
<DOC>
<DOCNO> 12507 </DOCNO>
Effective Dimension Transition of the Dynamics of Granular Materials in


  Phase transition of strongly excited granular materials in 2D pipe is
investigated numerically. By changing the ratio between width of the pipe and
the height of the granular bed, we observe the transition between the 1
dimensional like state and the actual 2 dimensional state. Moreover, it is
found that the character of the transition changes when the magnitude of
dissipation passes through a critical value.

</DOC>
<DOC>
<DOCNO> 8906 </DOCNO>
VanVleck Response Of A Two-Level System And Mesoscopic Orbital Magnetism


  We evaluate the mean value of the van Vleck response of a two-level system
with level spacing distribution and argue that it describes the orbital
magnetism of small conducting particles.

</DOC>
<DOC>
<DOCNO> 7733 </DOCNO>
First and second order transition in frustrated XY systems


  The nature of the phase transition for the XY stacked triangular
antiferromagnet (STA) is a controversial subject at present. The field
theoretical renormalization group (RG) in three dimensions predicts a first
order transition. This prediction disagrees with Monte Carlo (MC) simulations
which favor a new universality class or a tricritical transition. We simulate
by the Monte Carlo method two models derived from the STA by imposing the
constraint of local rigidity which should have the same critical behavior as
the original model. A strong first order transition is found. Following Zumbach
we analyze the second order transition observed in MC studies as due to a fixed
point in the complex plane. We review the experimental results in order to
clarify the different critical behavior observed.

</DOC>
<DOC>
<DOCNO> 119340 </DOCNO>
Infrared photometry of z~1 3C quasars


  We present JHKL' photometry of a complete sample of steep-spectrum radio-loud
quasars from the revised 3CR catalogue in the redshift range 0.65 < z < 1.20.
After correcting for contributions from emission lines and the host galaxies,
we investigate their spectral energy distributions (SEDs) around 1 micron.
About 75% of the quasars are tightly grouped in the plane of optical spectral
index, alpha_lo, versus near-infrared spectral index, alpha_hi, with the median
value of alpha_lo close to the canonical value, and the median alpha_hi
slightly flatter. We conclude that the fraction of moderately-obscured, red
quasars decreases with increasing radio power, in accordance with the `receding
torus' model which can also explain the relatively flat median near-infrared
spectra of the 3CR quasars. Two of the red quasars have inverted infrared
spectral indices, and we suggest that their unusual SEDs might result from a
combination of dust-scattered and transmitted quasar light.

</DOC>
<DOC>
<DOCNO> 13620 </DOCNO>
Collective versus single-particle effects in the optical spectra of


  We study optical spectra of finite electronic quantum systems at frequencies
smaller than the plasma frequency using a quasi-classical approach. This
approach includes collective effects and enables us to analyze how the nature
of the (single-particle) electron dynamics influences the optical spectra in
finite electronic quantum systems. We derive an analytical expression for the
low-frequency absorption coefficient of electro-magnetic radiation in a finite
quantum system with ballistic electron dynamics and specular reflection at the
boundaries: a two-dimensional electron gas confined to a strip of width a (the
approach can be applied to systems of any shape and electron dynamics --
diffusive or ballistic, regular or irregular motion). By comparing with results
of numerical computations using the random-phase approximation we show that our
analytical approach provides a qualitative and quantitative understanding of
the optical spectrum.

</DOC>
<DOC>
<DOCNO> 67655 </DOCNO>
Pion dispersion relation at finite temperature in the linear sigma model


  We develop one-loop effective vertices and propagators in the linear sigma
model at finite temperature satisfying the chiral Ward identities. We use these
in turn to compute the pion dispersion relation in a pion medium for small
momentum and temperatures on the order of the pion mass at next to leading
order in the parameter m_pi^2/4pi^2f_pi^2 and to zeroth order in the parameter
(m_pi/m_sigma)^2. We show that this expansion reproduces the result obtained
from chiral perturbation theory at leading order. The main effect is a
perturbative, temperature-dependent increase of the pion mass. We find no
qualitative changes in the pion dispersion curve with respect to the leading
order behavior in this kinematical regime.

</DOC>
<DOC>
<DOCNO> 13628 </DOCNO>
Laser-Induced Entangled Giant Quasi-Molecules in Optical Lattices


  We analyze atom-atom interactions in optical lattices due to a laser-induced
long-range interatomic force which prevails over the usual London-van der-Waals
forces. This force, which can be generated by an intense laser field at a
wavelength longer than that of the lattice-generating laser, is shown to bind
pairs of cold atoms trapped at different lattice sites, and cause their
translational quantum correlations (spatial entanglement).

</DOC>
<DOC>
<DOCNO> 12537 </DOCNO>
Classical Heisenberg antiferromagnet on a garnet lattice: a Monte Carlo


  We have studied a classical antiferromagnet on a garnet lattice by means of
Monte Carlo simulations in an attempt to examine the role of geometrical
frustration in Gadolinium Gallium Garnet, Gd3Ga5O12 (GGG). Low-temperature
specific heat, magnetisation, susceptibility, the autocorrelation function A(t)
and the neutron scattering function S(Q) have been calculated for several
models including different types of magnetic interactions and with the presence
of an external magnetic field applied along the principal symmetry axes. A
model, which includes only nearest-neighbour exchange, J1, neither orders down
to the lowest temperature nor does it show any tendency towards forming a
short-range coplanar spin structure. This model, however, does demonstrate a
magnetic field induced ordering below T ~ 0.01 J1. In order to reproduce the
experimentally observed properties of GGG, the simulated model must include
nearest neighbour exchange interactions and also dipolar forces. The presence
of weak next-to-nearest exchange interactions is found to be insignificant. In
zero field S(Q) exhibits diffuse magnetic scattering around positions in
reciprocal space where antiferromagnetic Bragg peaks appear in an applied
magnetic field.

</DOC>
<DOC>
<DOCNO> 12025 </DOCNO>
Dynamical spin-glass-like behavior in an evolutionary game


  We study a new evolutionary game, where players are tempted to take part by
the premium, but compete for being the first who take a specific move. Those,
who manage to escape the bulk of players, are the winners. While for large
premium the game is very similar to the Minority Game studied earlier,
significant new behavior, reminiscent of spin glasses is observed for premium
below certain level.

</DOC>
<DOC>
<DOCNO> 122391 </DOCNO>
The Star Formation History of the Milky Way


  Quantification of the Galaxy's star formation history involves both the
duration and the rate of formation, with these parameters being known with
different precision for different populations. The early rate of star formation
is knowable from modelling chemical element data, the recent rate directly from
isochrone analyses of colour-magnitude data. The field halo and globular
clusters are almost exclusively old, and formed in at most a few Gyr. The outer
bulge probably formed in a short period long ago -- extant data is
inconsistent, while the inner bulge/disk is forming today, and has continued to
form over time. Only very limited data is available on the inner disk. The
outer disk near the Sun seems as old as the halo. The earliest extended disk,
which forms the thick disk today, seems to have been in place very early, an
observation which is not simply consistent with some galaxy formation models.

</DOC>
<DOC>
<DOCNO> 11259 </DOCNO>
Molecular dynamics of flows in the Knudsen regime


  Novel technological applications often involve fluid flows in the Knudsen
regime in which the mean free path is comparable to the system size. We use
molecular dynamics simulations to study the transition between the dilute gas
and the dense fluid regimes as the fluid density is increased.

</DOC>
<DOC>
<DOCNO> 100075 </DOCNO>
The deformation quantization of certain super-Poisson brackets and BRST


  On every split supermanifold equipped with the Rothstein even super-Poisson
bracket we construct a deformation quantization by means of a Fedosov-type
procedure. In other words, the supercommutative algebra of all smooth sections
of the dual Grassmann algebra bundle of an arbitrarily given vector bundle E
(equipped with a fibre metric) over a symplectic manifold M will be deformed by
a series of bidifferential operators having first order supercommutator
proportional to the Rothstein superbracket. Moreover, we discuss two
constructions related to the above result, namely the quantized BRST-cohomology
for a locally free Hamiltonian Lie group action (together with H.-C.Herbig and
S.Waldmann) and the classical BRST cohomology in the general coistropic (or
reducible) case without using a `ghosts of ghosts' scheme (together with
H.-C.Herbig).

</DOC>
<DOC>
<DOCNO> 7936 </DOCNO>
Improved Theory of Single-Particle Properties Using Sea-bosons


  In this article, we combine the ideas introduced by us earlier in various
proportions to arrive at a simple and yet powerful means of studying
single-particle properties of homogeneous Fermi systems in detail without
making assumptions regarding the validity or otherwise of Fermi-liquid theory.
Novelties include the exact forms of the momentum distribution and spectral
functions in the intermediate density regime and a dielectric function that is
sensitive to significant qualitative changes in single-particle properties.
This time, care is taken to include the particle-hole mode by interpreting the
sum over modes as a weighted sum with the dynamical structure factor appearing
as the weight.

</DOC>
<DOC>
<DOCNO> 40199 </DOCNO>
Measurement of the B^0 meson properties using partially reconstructed


  The two B^0 decay processes B^0 --> D^{*-}pi^+ and B^0 --> D^{*-}l^+nu have
been studied by means of a partial reconstruction technique using a data sample
collected with the BABAR detector at the PEP-II storage ring. To increase
statistics, only the soft pi^- from the decay D^{*-} --> pi^-D^0 was used in
association with either an oppositely-charged high-momentum pion or lepton.
Events were then identified by exploiting the constraints from the simple
kinematics of Y(4S) decays. A clear signature is obtained in each case. The
position of the B^0 decay point was obtained from the reconstructed
pi^+(l^+)pi^- vertex. The position of the other anti-B^0 in the event was also
determined. Taking advantage of the boost given to the Y(4S) system by the
asymmetric beam energies of PEP-II, the lifetime of the B^0 meson has been
measured from the separation distance between the two vertices along the beam
direction. The preliminary results are tau_B0 = 1.55+/-0.05+/-0.07 ps, tau_B0 =
1.62+/-0.02+/-0.09 ps, respectively for the B^0 --> D^{*-}pi^+ and B^0 -->
D^{*-}l^+nu channels.

</DOC>
<DOC>
<DOCNO> 68915 </DOCNO>
Electroweak symmetry breaking by extra dimensions


  Electroweak symmetry breaking may be naturally induced by the observed quark
and gauge fields in extra dimensions without a fundamental Higgs field. We show
that a composite Higgs doublet can arise as a bound state of $(t, b)_L$ and a
linear combination of the Kaluza-Klein states of $t_R$, due to QCD in extra
dimensions. The top quark mass depends on the number of active $t_R$
Kaluza-Klein modes, and is consistent with the experimental value.

</DOC>
<DOC>
<DOCNO> 12054 </DOCNO>
Ordering and partial ordering in holmium titanate and related systems


  We take another look at two compounds which have been discussed as possible
realizations of ``spin ice'', namely holmium titanate and dysprosium titanate.
As we have earlier observed, holmium titanate does not display ice-like
behaviour at low temperatures because the long ranged dipolar interactions
between spins are strong compared to the nearest neighbour interactions. We
show, analytically, that the true ground state of this system must be fully
ordered, but simulations only reach partially ordered states because there are
infinite energy barriers separating these from the true ground state. We also
show that the true ground state of our model of dysprosium titanate is also
fully ordered, and offer some explanations as to why simulations and
experiments show ice-like behaviour. We discuss the effect on these systems of
an applied magnetic field. Finally, we discuss several other models which show
similar partial or full ordering in their ground states, including the well
known Ising model on the fcc lattice.

</DOC>
<DOC>
<DOCNO> 71404 </DOCNO>
On the contribution of density perturbations and gravitational waves to


  The important studies of Peebles, and Bond and Efstathiou have led to the
formula C_l = const/[l(l +1)] aimed at describing the lower order multipoles of
the CMBR temperature variations caused by density perturbations with the flat
spectrum. Clearly, this formula requires amendments, as it predicts an
infinitely large monopole C_0, and a dipole moment C_1 only 6/2 times larger
than the quadrupole C_2, both predictions in conflict with observations. We
restore the terms omitted in the course of the derivation of this formula, and
arrive at a new expression. According to the corrected formula, the monopole
moment is finite and small, while the dipole moment is sensitive to
short-wavelength perturbations, and numerically much larger than the
quadrupole, as one would expect on physical grounds. At the same time, the
function l(l +1)C_l deviates from a horizontal line and grows with l, for l
\geq 2. We show that the inclusion of the modulating (transfer) function
terminates the growth and forms the first peak, recently observed. We fit the
theoretical curves to the position and height of the first peak, as well as to
the observed dipole, varying three parameters: red-shift at decoupling,
red-shift at matter-radiation equality, and slope of the primordial spectrum.
It appears that there is always a deficit, as compared with the COBE
observations, at small multipoles, l \sim 10. We demonstrate that a reasonable
and theoretically expected amount of gravitational waves bridges this gap at
small multipoles, leaving the other fits as good as before. We show that the
observationally acceptable models permit somewhat `blue' primordial spectra.
This allows one to avoid the infra-red divergence of cosmological
perturbations, which is otherwise present.

</DOC>
<DOC>
<DOCNO> 152458 </DOCNO>
Holographic Noncommutativity


  We examine noncommutative Yang-Mills and open string theories using
magnetically and electrically deformed supergravity duals. The duals are near
horizon regions of Dp-brane bound state solutions which are obtained by using
O(p+1,p+1) transformations of Dp-branes. The action of the T-duality group
implies that the noncommutativity parameter is constant along holographic
RG-flows. The moduli of the noncommutative theory, i.e., the open string metric
and coupling constant, as well as the zero-force condition are shown to be
invariant under the O(p+1,p+1) transformation, i.e., deformation independent.
We find sufficient conditions, including zero force and constant dilaton in the
ISO(3,1)-invariant D3 brane solution, for exact S-duality between
noncommutative Yang-Mills and open string theories. These results are used to
construct noncommutative field and string theories with N=1 supersymmetry from
the T^(1,1) and Pilch-Warner solutions. The latter has a non-trivial zero-force
condition due to the warping.

</DOC>
<DOC>
<DOCNO> 170454 </DOCNO>
Comprehensive experimental test of quantum erasure


  In an interferometer, path information and interference visibility are
incompatible quantities. Complete determination of the path will exclude any
possibility of interference, rendering the visibility zero. However, if the
composite object and probe state is pure, it is, under certain conditions,
possible to trade the path information for improved (conditioned) visibility.
Such a procedure is called quantum erasure. We have performed such experiments
with polarization entangled photon pairs. Using a partial polarizer we could
vary the degree of entanglement between object and probe. We could also vary
the interferometer splitting ratio and thereby vary the a priori path
predictability. We have tested quantum erasure under a number of different
experimental conditions and found good agreement between experiments and
theory.

</DOC>
<DOC>
<DOCNO> 9905 </DOCNO>
Comment on "Two Dimensional Ordering and Fluctuations in alpha'-NaV2O5"


  We claim that the analysis presented by Gaulin et al. (Phys. Rev. Lett. 84,
3446 (2000)) does not prove the two-dimensional character of the transition in
NaV2O5 nor the charge ordering mechanism of the transition.

</DOC>
<DOC>
<DOCNO> 70008 </DOCNO>
The compatibility of diffractive hard scattering in p pbar and ep


  We show that the data for diffractive dijet production at the Tevatron p pbar
collider are consistent with diffractive deep inelastic e p data collected at
HERA. The breakdown of factorization between the two data sets is naturally
explained by a strong tendency to populate the rapidity gap in the p pbar
diffractive process by secondaries from soft underlying interactions and by
bremsstrahlung associated with the presence of the hard dijet subprocess.

</DOC>
<DOC>
<DOCNO> 70738 </DOCNO>
Neutrino Masses and Mixing Angles in a Realistic String-Inspired Model


  We analyse a supersymmetric string-inspired model of all fermion masses and
mixing angles based on the Pati-Salam $SU(4)\times SU(2)_L \times SU(2)_R$
gauge group supplemented by a $U(1)_X$ flavour symmetry.
 The model involves third family Yukawa unification and predicts the top mass
and the ratio of the vacuum expectation values $\tan \beta$.
 The model also provides a successful description of the CKM matrix and
predicts the masses of the down and strange quarks.
 However our main focus is on the neutrino masses and MNS mixing angles, and we
show how the recent atmospheric neutrino mixing observed by Super-Kamiokande,
and the MSW solution to the solar neutrino problem lead to important
information about the flavour structure of the model near the string scale.
 We show how single right-handed neutrino dominance may be implemented by the
use of ``Clebsch zeros'', leading to the LMA MSW solution, corresponding to
bi-maximal mixing. The LOW MSW and SMA MSW solutions are also discussed.

</DOC>
<DOC>
<DOCNO> 69247 </DOCNO>
Covariant Quark-Representation of Composite Meson Systems and Chiral


  Assuming the spin-independence for confining force, we give a covariant quark
representation of general composite meson systems with definite Lorentz
transformation properties. For benefit of this representation we are able to
deduce automatically the transformation rules of composite mesons for general
symmetry operations from those of constituent (exciton) quarks. Applying this
we investigate especially physical implication of chiral symmetry for the meson
systems, and point out a possibility of existence of new meson multiplets.

</DOC>
<DOC>
<DOCNO> 84695 </DOCNO>
Cumulative gravitational lensing in Newtonian perturbations of


  It is a common assumption amongst astronomers that, in the determination of
the distances of remote sources from their apparent brightness, the cumulative
gravitational lensing due to the matter in all the galaxies is the same, on
average, as if the matter were uniformly distributed throughout the cosmos. The
validity of this assumption is considered here by way of general Newtonian
perturbations of Friedman-Robertson-Walker (FRW) cosmologies. The analysis is
carried out in synchronous gauge, with particular attention to an additional
gauge condition that must be imposed. The mean correction to the apparent
magnitude-redshift relation is obtained for an arbitrary mean density
perturbation. In the case of a zero mean density perturbation, when the
intergalactic matter has a dust equation of state, then there is indeed a
zero-mean first order correction to the apparent magnitude-redshift relation
for all redshifts. Point particle and Swiss cheese models are considered as
particular cases.

</DOC>
<DOC>
<DOCNO> 170428 </DOCNO>
Entanglement of Formation of an Arbitrary State of Two Rebits


  We consider entanglement for quantum states defined in vector spaces over the
real numbers. Such real entanglement is different from entanglement in standard
quantum mechanics over the complex numbers. The differences provide insight
into the nature of entanglement in standard quantum theory. Wootters [Phys.
Rev. Lett. 80, 2245 (1998)] has given an explicit formula for the entanglement
of formation of two qubits in terms of what he calls the concurrence of the
joint density operator. We give a contrasting formula for the entanglement of
formation of an arbitrary state of two ``rebits,'' a rebit being a system whose
Hilbert space is a 2-dimensional real vector space.

</DOC>
<DOC>
<DOCNO> 170348 </DOCNO>
A convenient method to prepare the effective pure state in a quantum


  A simple method is proposed to prepare conveniently the effective pure state
|00...0><0...00| with any number of qubits in a quantum ensemble. The
preparation is based on the temporal averaging (Knill, Chuang, and Laflamme,
Phys.Rev.A 57, 3348(1998)). The quantum circuit to prepare the effective pure
state is designed in a unified and systematical form and is explicitly
decomposed completely into a product of a series of one-qubit quantum gates and
the two-qubit diagonal quantum gates. The preparation could be programmed and
implemented conveniently on an NMR quantum computer.

</DOC>
<DOC>
<DOCNO> 119335 </DOCNO>
Unusual quiescent X-ray activity from XTE J0421+560 (CI Cam)


  We report on BeppoSAX observations of the X-ray transient XTE J0421+560 in
quiescence 156, 541, and ~690 days after the maximum of the 1998 April
outburst. In the first observation the source was soft with a power-law photon
index of 4.0 (+1.9 -0.9) and absorption, NH, of (1.1 +4.9 -1.1) X 10^21
atom/cm2. In the second observation, the source brightened by a factor ~15 in
the 1-10 keV energy range, became significantly harder with a photon index of
1.86 (+0.27 -0.32) and was strongly absorbed with NH = (4.0 +/- 0.8) X 10^23
atom/cm2. There is evidence for a narrow emission line in both spectra at \~7
keV. In the third observation, the source had faded by a factor ~$8 from the
previous observation to below the BeppoSAX detection level. It is possible that
these variations result from orbital motion of a compact object around the B[e]
star companion with the intense, absorbed, spectrum arising during passage
through dense circumstellar material. If this is the case, the system may be
continuing to exhibit periodic activity.

</DOC>
<DOC>
<DOCNO> 120638 </DOCNO>
Keck Mid-Infrared Imaging of the QSO 2237+0305


  Using the Long Wavelength Spectrometer on Keck I, we have imaged the
gravitationally lensed radio quiet quasi-stellar object (QSO) 2237+0305 at 8.9
and 11.7 microns for the first time. The mid-infrared flux ratios are
inconsistent with the optical flux ratios, but agree with the radio flux ratios
and with some published gravitational lens models. These flux ratios indicate
that the infrared emission is not affected by microlensing, which rules out the
synchrotron emission model. The infrared emission is likely produced by hot
dust extended on a length scale of more than 0.03 parsecs. The spectral energy
distribution further implies a narrow range of dust temperatures, suggesting
that the dust may be located in a shell extending between ~1 to 3 parsecs from
the nucleus, and intercepting about half of the QSO luminosity.

</DOC>
<DOC>
<DOCNO> 102448 </DOCNO>
Small Elliptic Quantum Group $e_{tau,\gamma}(sl_N)$


  The small elliptic quantum group $e_{\tau,\gamma}(sl_N)$, introduced in the
paper, is an elliptic dynamical analogue of the universal enveloping algebra
$U(sl_n)$. We define highest weight modules, Verma modules and contragradient
modules over $e_{\tau,\gamma}(sl_N)$, the dynamical Shapovalov form for
$e_{\tau,\gamma}(sl_N)$ and the contravariant form for highest weight
$e_{\tau,\gamma}(sl_N)$-modules. We show that any finite-dimensional
$sl_N$-module and any Verma module over $sl_N$ can be lifted to the
corresponding $e_{\tau,\gamma}(sl_N)$-module on the same vector space. For the
elliptic quantum group $E_{\tau,\gamma}(sl_N)$ we construct the evaluation
morphism $E_{\tau,\gamma}(sl_N)\to e_{\tau,\gamma}(sl_N)$, thus making any
$e_{\tau,\gamma}(sl_N)$-module into an evaluation
$E_{\tau,\gamma}(sl_N)$-module.

</DOC>
<DOC>
<DOCNO> 151289 </DOCNO>
BPS Saturated Domain Walls along a Compact Dimension


  Generalized Wess-Zumino models which admit topologically non-trivial BPS
saturated configurations along one compact, spatial dimension are investigated
in various dimensions of space-time. We show that, in a representative model
and for sufficiently large circumference, there are BPS configurations along
the compact dimension containing an arbitrary number of equidistant,
well-separated domain walls. We analyze the spectrum of the bosonic and
fermionic light and massless modes that are localized on these walls. The
masses of the light modes are exponentially suppressed by the ratio of the
distance between the walls and their width. States that are initially localized
on one wall oscillate in time between all the walls. In (2+1) dimensions the
``chirality'' of localized, massless fermions is determined. In the
(1+1)-dimensional case we show how the mass of certain classically BPS
saturated solitons is lifted above the BPS bound by instanton tunneling.

</DOC>
<DOC>
<DOCNO> 11429 </DOCNO>
Shape-induced magnetic anisotropy in dilute magnetic alloys


  We extend the theory of the surface-induced magnetic anisotropy to mesoscopic
samples with arbitrary geometry. The shape-induced anisotropy of impurity spins
in small brick-shaped grains of dilute magnetic alloys is studied in detail.
The surface-induced blocking of a magnetic-impurity spin is shown to be very
sensitive to geometric parameters of a grain. This implies that the apparent
discrepancy between the experimental data of different groups on the size
dependence of the Kondo resistivity can result from different microstructure of
the used samples. In order to interpret recent experimental data on the
anomalous Hall effect in thin polycrystalline Fe doped Au films, we analyse the
magnetisation of impurity spins as a function of the impurity position and of
the grain shape.

</DOC>
<DOC>
<DOCNO> 100698 </DOCNO>
Feynman diagrams and polylogarithms: shuffles and pentagons


  We summarize the Hopf algebra structure on Feynman diagrams and emphasize the
interest in further algebraic structures hidden in Feynman graphs.

</DOC>
<DOC>
<DOCNO> 122563 </DOCNO>
Discovery of 101-s Pulsations from AX J0057.4-7325 in the SMC with ASCA


  The results from two ASCA observations of AX J0057.4-7325 = RX J0057.3-7325
are presented. Coherent pulsations with a barycentric period of 101.45 +/- 0.07
s were discovered in the second observation. The X-ray spectrum was found to be
hard (photon index ~ 0.9) and unchanged through these observations, except for
the flux. The ROSAT archival data show that AX J0057.4-7325 exhibits a flux
variation with a factor >~ 10. A discussion on a possible optical counterpart
is given.

</DOC>
<DOC>
<DOCNO> 117124 </DOCNO>
Microtorus: a High Finesse Microcavity with Whispering-Gallery Modes


  We have demonstrated a 165 micron oblate spheroidal microcavity with free
spectral range 383.7 GHz (3.06nm), resonance bandwidth 25 MHz (Q ~ 10^7) at
1550nm, and finesse F > 10^4. The highly oblate spheroidal dielectric
microcavity combines very high Q-factor, typical of microspheres, with vastly
reduced number of excited whispering-gallery (WG) modes (by two orders of
magnitude). The very large free spectral range in the novel microcavity - few
hundred instead of few GigaHertz in typical microspheres - is desirable for
applications in spectral analysis, narrow-linewidth optical and RF oscillators,
and cavity QED.

</DOC>
<DOC>
<DOCNO> 99828 </DOCNO>
A Probabilistic Approach to Conjugacy Classes in the Finite Symplectic


  Markov chains are used to give a purely probabilistic way of understanding
the conjugacy classes of the finite symplectic and orthogonal groups in odd
characteristic. As a corollary of these methods one obtains a probabilistic
proof of Steinberg's count of unipotent matrices and generalizations of
formulas of Rudvalis and Shinoda.

</DOC>
<DOC>
<DOCNO> 85094 </DOCNO>
The Dirac field in Taub-NUT background


  We investigate the SO(4,1) gauge-invariant theory of the Dirac fermions in
the external field of the Kaluza-Klein monopole, pointing out that the quantum
modes can be recovered from a Klein-Gordon equation analogous to the Schr\"
odinger equation in the Taub-NUT background. Moreover, we show that there is a
large collection of observables that can be directly derived from those of the
scalar theory. These offer many possibilities of choosing complete sets of
commuting operators which determine the quantum modes. In addition there are
some spin- like and Dirac-type operators involving the covariantly constant
Killing-Yano tensors of the hyper-K\" ahler Taub-NUT space. The energy
eigenspinors of the central modes in spherical coordinates are completely
evaluated in explicit, closed form.

</DOC>
<DOC>
<DOCNO> 102522 </DOCNO>
Toric Varieties in Hilbert Schemes


  For an arbitrary field K, let I be an ideal in the ring K[[x,y]] expressible
as a polynomial in either the pair of ideals (x, y^4) and (x,y) or the pair
(x,y^3) and (x^2, y). Let G be the group of automorphisms of K[[x,y]] sending
the ideal (x,y^2) to itself. Then the normalization of the closure of the G
orbit of I is a toric variety. We use the interplay of the properties of
Hilbert schemes and toric varieties to study these spaces.

</DOC>
<DOC>
<DOCNO> 169768 </DOCNO>
On the Additivity of the Entanglement of Formation


  We withdraw this paper due to insufficient arguments in the derivation of
Theorem 1. See quant-ph/0005062 for the new paper

</DOC>
<DOC>
<DOCNO> 13608 </DOCNO>
Low-lying excitations of a trapped rotating Bose-Einstein condensate


  We investigate the low-lying excitations of a weakly-interacting,
harmonically-trapped Bose-Einstein condensed gas under rotation, in the limit
where the angular mometum $L$ of the system is much less than the number of the
atoms $N$ in the trap. We show that in the asymptotic limit $N \to \infty$ the
excitation energy, measured from the energy of the lowest state, is given by
$27 N_{3}(N_{3}-1) v_0 /68$, where $N_{3}$ is the number of octupole
excitations and $v_{0}$ is the unit of the interaction energy.

</DOC>
<DOC>
<DOCNO> 121945 </DOCNO>
A simple tool for assessing the completeness in apparent magnitude of


  A new tool is proposed for finding out the completeness limit in apparent
magnitude of a magnitude-redshift sample. The technique, closely related to the
statistical test proposed by Efron & Petrosian (1992), presents a real
improvement compared to standard completeness tests. Namely, no a priori
assumptions are required concerning the redshift space distribution of the
sources. It means in particular that neither the clustering nor the evolution
of the mean number density of the galaxies do affect the result of the search.

</DOC>
<DOC>
<DOCNO> 70358 </DOCNO>
Coupling of Baryon Resonances to the $N \omega$ channel


  We estimate the resonance coupling strength $f_{RN\omega}$ and $f_{RN\rho}$
from a Vector Meson Dominance (VMD) analysis. The isoscalar and isovector part
of the photon coupling are obtained separately from helicity amplitudes. The
reliability of this approach is tested by comparing VMD predictions for
$f_{RN\rho}$ with values obtained from fitting the hadronic decay widths into
$N \rho$. A reasonable agreement is found, but VMD tends to underestimate the
coupling constants. In order to confirm consistency with experimental data, we
calculate the cross-sections for photon-and pion induced reactions within a
{\it Breit-Wigner} model. Finally, we study how the properties of $\omega$
mesons in nuclear matter are affected from the excitation of resonance-hole
loops. For an $\omega$ at rest, we find a broadening of about 40 MeV, while at
higher momenta the effect of resonance excitations is reduced.

</DOC>
<DOC>
<DOCNO> 83511 </DOCNO>
The Tale of One-way Functions


  The existence of one-way functions (owf) is arguably the most important
problem in computer theory. The article discusses and refines a number of
concepts relevant to this problem. For instance, it gives the first
combinatorial complete owf, i.e. a function which is one-way if any function
is. There are surprisingly many subtleties in basic definitions. Some of these
subtleties are discussed or hinted at in the literature and some are
overlooked. This article attempts a unified approach.

</DOC>
<DOC>
<DOCNO> 118396 </DOCNO>
The jet-disk symbiosis model for Gamma Ray Bursts: cosmic ray and


  The relation between the cosmological evolution of the jet-disk symbiosis
model for GRBs and the cosmic rays energy distribution is presented. We used
two different Star Formation Rates (SFR) as a function of redshift and a
Luminosity Function (LF) distribution to obtain the distribution in fluence of
GRBs in our model and compare it with the data. We show a good agreement
between the fluence distribution we obtain and the corrected data for the 4B
BATSE catalogue. The results we obtain are generally valid for models that use
jet physics to explain GRB properties. The fluence in the gamma ray band has
been used to calculate the energy in cosmic rays both in our Galaxy and at
extragalactic distances as a function of the redshift. This energy input has
been compared with the Galactic and extragalactic spectrum of cosmic rays and
neutrinos. Using our jet disk symbiosis model, we found that in both cases GRBs
cannot give any significant contribution to cosmic rays. We also estimate the
neutrino background, obtaining a very low predicted flux. We also show that the
fit of our model with the corrected fluence distribution of GRBs gives strong
constraints of the star formation rate as a function of the redshift.

</DOC>
<DOC>
<DOCNO> 85591 </DOCNO>
Discrete Black-Hole Radiation and the Information Loss Paradox


  Hawking's black hole information puzzle highlights the incompatibility
between our present understanding of gravity and quantum physics. However,
Hawking's prediction of black-hole evaporation is at a semiclassical level. One
therefore suspects some modifications of the character of the radiation when
quantum properties of the {\it black hole itself} are properly taken into
account. In fact, during the last three decades evidence has been mounting
that, in a quantum theory of gravity black holes may have a discrete mass
spectrum, with concomitant {\it discrete} line emission. A direct consequence
of this intriguing prediction is that, compared with blackbody radiation,
black-hole radiance is {\it less} entropic, and may therefore carry a
significant amount of {\it information}. Using standard ideas from quantum
information theory, we calculate the rate at which information can be recovered
from the black-hole spectral lines. We conclude that the information that was
suspected to be lost may gradually leak back, encoded into the black-hole
spectral lines.

</DOC>
<DOC>
<DOCNO> 122806 </DOCNO>
Assisted stellar suicide: the wind-driven evolution of the recurrent


  We show that the extremely high luminosity of the short-period recurrent nova
T Pyx in quiescence can be understood if this system is a wind-driven supersoft
x-ray source (SSS). In this scenario, a strong, radiation-induced wind is
excited from the secondary star and accelerates the binary evolution. The
accretion rate is therefore much higher than in an ordinary cataclysmic binary
at the same orbital period, as is the luminosity of the white dwarf primary. In
the steady state, the enhanced luminosity is just sufficient to maintain the
wind from the secondary. The accretion rate and luminosity predicted by the
wind-driven model for T Pyx are in good agreement with the observational
evidence. X-ray observations with Chandra or XMM may be able to confirm T Pyx's
status as a SSS.
  T Pyx's lifetime in the wind-driven state is on the order of a million years.
Its ultimate fate is not certain, but the system may very well end up
destroying itself, either via the complete evaporation of the secondary star,
or in a Type Ia supernova if the white dwarf reaches the Chandrasekhar limit.
Thus either the primary, the secondary, or both may currently be committing
assisted stellar suicide.

</DOC>
<DOC>
<DOCNO> 100593 </DOCNO>
Quasi-actions on trees: research announcement


  We develop a battery of tools for studying quasi-isometric rigidity and
classification problems for splittings of groups. The techniques work best for
finite graphs of groups where all edge and vertex groups are coarse PD groups.
For example, if Gamma is a graph of coarse PD(n) groups for a fixed n, if the
Bass-Serre tree of Gamma has infinitely many ends, and if H is a finitely
generated group quasi-isometric to pi_1(Gamma), then we prove that H is the
fundamental group of a graph of coarse PD(n) groups, with vertex and edge
groups quasi-isometric to those of Gamma. We also have quasi-isometric rigidity
theorems for graphs of coarse PD groups of nonconstant dimension, under various
assumptions on the edge-to-vertex group inclusions.

</DOC>
<DOC>
<DOCNO> 170206 </DOCNO>
Single photon generation by pulsed excitation of a single dipole


  The fluorescence of a single dipole excited by an intense light pulse can
lead to the generation of another light pulse containing a single photon. The
influence of the duration and energy of the excitation pulse on the number of
photons in the fluorescence pulse is studied. The case of a two-level dipole
with strongly damped coherences is considered. The presence of a metastable
state leading to shelving is also investigated.

</DOC>
<DOC>
<DOCNO> 40651 </DOCNO>
Searching for physics beyond the Standard Model in the decay B+ ->


  The observation potential of the decay B+ -> K+K+pi- with the ATLAS detector
at LHC is described in this paper. In the Standard Model this decay mode is
highly suppressed, while in models beyond the Standard Model it could be
significantly enhanced. To improve the selection of the K+K+pi- final state, a
charged hadron identification using Time-over-Threshold measurements in the
ATLAS Transition Radiation Tracker was developed and used.

</DOC>
<DOC>
<DOCNO> 12737 </DOCNO>
Re-integerization of fractional charges in the correlated quarter-filled


  Previous work has demonstrated the existence of soliton defect states with
charges +/- e/2 in the limits of zero and of infinite on-site Coulomb
interactions in the one-dimensional (1D) quarter-filled band. For large but
finite on-site Coulomb interaction, the low temperature 2k_F bond distortion
that occurs within the 4k_F bond-distorted phase is accompanied by
charge-ordering on the sites. We show that a ``re-integerization'' of the
defect charge occurs in this bond-charge density wave (BCDW) state due to a
``binding'' of the fractional charges. We indicate briefly possible
implications of this result for mechanisms of organic superconductivity.

</DOC>
<DOC>
<DOCNO> 122616 </DOCNO>
Ultraviolet Signposts of Resonant Dynamics in the Starburst-Ringed Sab


  M94 (NGC 4736) is investigated using images from the Ultraviolet Imaging
Telescope (FUV-band), Hubble Space Telescope (NUV-band), Kitt Peak 0.9-m
telescope (H-alpha, R, and I bands), and Palomar 5-m telescope (B-band), along
with spectra from the International Ultraviolet Explorer and Lick 1-m
telescopes. The wide-field UIT image shows FUV emission from (a) an elongated
nucleus, (b) a diffuse inner disk, where H-alpha is observed in absorption, (c)
a bright inner ring of H II regions at the perimeter of the inner disk (R = 48
arcsec. = 1.1 kpc), and (d) two 500-pc size knots of hot stars exterior to the
ring on diametrically opposite sides of the nucleus (R= 130 arcsec. = 2.9 kpc).
The HST/FOC image resolves the NUV emission from the nuclear region into a
bright core and a faint 20 arcsec. long ``mini-bar'' at a position angle of 30
deg. Optical and IUE spectroscopy of the nucleus and diffuse inner disk
indicates an approximately 10^7 or 10^8 yr-old stellar population from
low-level starbirth activity blended with some LINER activity. Analysis of the
H-alpha, FUV, NUV, B, R, and I-band emission along with other observed tracers
of stars and gas in M94 indicates that most of the star formation is being
orchestrated via ring-bar dynamics involving the nuclear mini-bar, inner ring,
oval disk, and outer ring. The inner starburst ring and bi-symmetric knots at
intermediate radius, in particular, argue for bar-mediated resonances as the
primary drivers of evolution in M94 at the present epoch. Similar processes may
be governing the evolution of the ``core-dominated'' galaxies that have been
observed at high redshift. The gravitationally-lensed ``Pretzel Galaxy''
(0024+1654) at a redshift of approximately 1.5 provides an important precedent
in this regard.

</DOC>
<DOC>
<DOCNO> 100703 </DOCNO>
Classification of certain simple $C^*$-algebras with torsion in $K_1$


  We show that the Elliott invariant is a classifying invariant for the class
of $C^*$-algebras that are simple unital infinite dimensional inductive limits
of sequences of finite direct sums of building blocks of the form $$ \{f\in
C(\T)\otimes M_n: f(x_i)\in M_{d_i}, i=1,2,...,N\}, $$ where
$x_1,x_2,...,x_N\in\T$, $d_1,d_2,...,d_N$ are integers dividing $n$, and
$M_{d_i}$ is embedded unitally into $M_n$. Furthermore we prove existence and
uniqueness theorems for *-homomorphisms between such algebras and we identify
the range of the invariant.

</DOC>
<DOC>
<DOCNO> 120552 </DOCNO>
Can we really rule out the existence of antistars?


  The existence of large domains of antimatter is still an open question. Some
space mission and experiments in the near future are expected to give
reasonable answer to that question. Meanwhile, we can try to search for other
signatures of the presence of antimatter. This paper presents a discussion
about possible effects of the close encounter of stars and antistars. It is
known that the accretion power can be higher in presence of antimatter, because
of high-energy photons generated in annihilation, which result in a smaller
radiation pressure. Therefore, the Eddington luminosity can reach higher
values. Calculations of the gamma-ray flux above 100 MeV, and comparison with
recent data from satellites, show a good agreement for certain sources. So,
let's play some science-fiction!

</DOC>
<DOC>
<DOCNO> 122136 </DOCNO>
Unbiased Reconstruction of the Large Scale Structure


  We present a new Unbiased Minimal Variance (UMV) estimator for the purpose of
reconstructing the large--scale structure of the universe from noisy, sparse
and incomplete data. Similar to the Wiener Filter (WF), the UMV estimator is
derived by requiring the linear minimal variance solution given the data and an
assumed prior model specifying the underlying field covariance matrix. However,
unlike the WF, the minimization is carried out with the added constraint of an
unbiased reconstructed mean field. The new estimator does not necessitate a
noise model to estimate the underlying field; however, such a model is required
for evaluating the errors at each point in space. The general application of
the UMV estimator is to predict the values of the reconstructed field in
un-sampled regions of space (e.g., interpolation in the unobserved Zone of
Avoidance), and to dynamically transform from one measured field to another
(e.g., inversion of radial peculiar velocities to over-densities). Here, we
provide two very simple applications of the method. The first, is to recover a
1D signal from noisy, convolved data with gaps, e.g., CMB time-ordered data.
The second application is a reconstruction of the density and 3D peculiar
velocity fields from mock SEcat galaxy peculiar velocity catalogs.

</DOC>
<DOC>
<DOCNO> 68599 </DOCNO>
Toward the correlated analysis of perturbative QCD observables


  We establish direct connection between ghost-free formulations of
RG-invariant perturbation theory in the both Euclidean and Minkowskian regions.
By combining the trick of resummation of the $\pi^2$-terms for the invariant
QCD coupling and observables in the time-like region with fresh results on the
"analyticized" coupling $\alpha_{\rm an}(Q^2)$ and observables in the
space-like domain we formulate a self-consistent scheme, free of ghost
troubles. The basic point of this joint construction is the "dipole spectral
relation" emerging from axioms of local QFT. Then we consider the issue of the
heavy quark thresholds and devise a global scheme for the data analysis in the
whole accessible space-like and time-like domain with various numbers of active
quarks. Observables in both the regions are presented in a form of non-power
perturbation series with improved convergence properties. Preliminary estimates
indicate that this global scheme produces results a bit different - on a few
per cent level for $\bar{\alpha}_s$ - from the usual one, thus influencing the
total picture of the QCD parameters correlation.

</DOC>
<DOC>
<DOCNO> 169602 </DOCNO>
Comment on "Hidden assumptions in decoherence theory"


  It is shown that the conclusion of the paper "Hidden assumptions in
decoherence theory" (quant-ph/0001021) is the result of a misunderstanding of
the concept of pointer states. It is argued that pointer states are selected by
the interaction of quantum systems with the environment, and are not based on
any measurement by a conscious observer.

</DOC>
<DOC>
<DOCNO> 83330 </DOCNO>
Science User Scenarios for a Virtual Observatory Design Reference


  The knowledge discovery potential of the new large astronomical databases is
vast. When these are used in conjunction with the rich legacy data archives,
the opportunities for scientific discovery multiply rapidly. A Virtual
Observatory (VO) framework will enable transparent and efficient access,
search, retrieval, and visualization of data across multiple data repositories,
which are generally heterogeneous and distributed. Aspects of data mining that
apply to a variety of science user scenarios with a VO are reviewed. The
development of a VO should address the data mining needs of various
astronomical research constituencies. By way of example, two user scenarios are
presented which invoke applications and linkages of data across the catalog and
image domains in order to address specific astrophysics research problems.
These illustrate a subset of the desired capabilities and power of the VO, and
as such they represent potential components of a VO Design Reference Mission.

</DOC>
<DOC>
<DOCNO> 11368 </DOCNO>
Random graphs with arbitrary degree distributions and their applications


  Recent work on the structure of social networks and the internet has focussed
attention on graphs with distributions of vertex degree that are significantly
different from the Poisson degree distributions that have been widely studied
in the past. In this paper we develop in detail the theory of random graphs
with arbitrary degree distributions. In addition to simple undirected,
unipartite graphs, we examine the properties of directed and bipartite graphs.
Among other results, we derive exact expressions for the position of the phase
transition at which a giant component first forms, the mean component size, the
size of the giant component if there is one, the mean number of vertices a
certain distance away from a randomly chosen vertex, and the average
vertex-vertex distance within a graph. We apply our theory to some real-world
graphs, including the world-wide web and collaboration graphs of scientists and
Fortune 1000 company directors. We demonstrate that in some cases random graphs
with appropriate distributions of vertex degree predict with surprising
accuracy the behavior of the real world, while in others there is a measurable
discrepancy between theory and reality, perhaps indicating the presence of
additional social structure in the network that is not captured by the random
graph.

</DOC>
<DOC>
<DOCNO> 117634 </DOCNO>
Profiles of Strong Permitted Lines in Classical T Tauri Stars


  We present a spectral analysis of 30 T Tauri stars observed with the Hamilton
echelle spectrograph over more than a decade. One goal is to test
magnetospheric accretion model predictions. Observational evidence previously
published supporting the model, such as emission line asymmetry and a high
frequency of redshifted absorption components, are considered. We also discuss
the relation between different line forming regions and search for good
accretion rate indicators.
  In this work we confirm several important points of the models, such as the
correlation between accretion and outflow, broad emission components that are
mostly central or slightly blueshifted and only the occasional presence of
redshifted absorption. We also show, however, that the broad emission
components supposedly formed in the magnetospheric accretion flow only
partially support the models. Unlike the predictions, they are sometimes
redshifted, and are mostly found to be symmetric. The published theoretical
profiles do not have a strong resemblance to our observed ones. We emphasize
the need for accretion models to include a strong turbulent component before
their profiles will match the observations. The effects of rotation, and the
outflow components, will also be needed to complete the picture.

</DOC>
<DOC>
<DOCNO> 178830 </DOCNO>
Rare isotope production in statistical multifragmentation


  Producing rare isotopes through statistical multifragmentation is
investigated using the Mekjian method for exact solutions of the canonical
ensemble. Both the initial fragmentation and the the sequential decay are
modeled in such a way as to avoid Monte Carlo and thus provide yields for
arbitrarily scarce fragments. The importance of sequential decay, exact
particle-number conservation and the sensitivities to parameters such as
density and temperature are explored. Recent measurements of isotope ratios
from the fragmentation of different Sn isotopes are interpreted within this
picture.

</DOC>
<DOC>
<DOCNO> 67917 </DOCNO>
Weak-Singlet Fermions: Models and Constraints


  We employ data from precision electroweak tests and collider searches to
derive constraints on the possibility that weak-singlet fermions mix with the
ordinary Standard Model fermions. Our findings are presented within the context
of a theory with weak-singlet partners for all ordinary fermions and theories
in which only third-generation fermions mix with weak singlets. In addition, we
indicate how certain results can be applied more widely in theories containing
exotic fermions.

</DOC>
<DOC>
<DOCNO> 70942 </DOCNO>
b --> s g g decay in the two and three Higgs doublet models with CP


  We study the decay width and CP-asymmetry of the inclusive process b--> s g g
(g denotes gluon) in the three and two Higgs doublet models with complex Yukawa
couplings. We analyse the dependencies of the differential decay width and
CP-asymmetry to the s- quark energy E_s and CP violating parameter \theta. We
observe that there exist a considerable enhancement in the decay width and CP
asymmetry is at the order of 10^{-2}. Further, it is possible to predict the
sign of C_7^{eff} using the CP asymmetry.

</DOC>
<DOC>
<DOCNO> 70047 </DOCNO>
Nonequilibrium perturbation theory for spin-1/2 fields


  A partial resummation of perturbation theory is described for field theories
containing spin-1/2 particles in states that may be far from thermal
equilibrium. This allows the nonequilibrium state to be characterized in terms
of quasiparticles that approximate its true elementary excitations. In
particular, the quasiparticles have dispersion relations that differ from those
of free particles, finite thermal widths and occupation numbers which, in
contrast to those of standard perturbation theory evolve with the changing
nonequilibrium environment. A description of this kind is essential for
estimating the evolution of the system over extended periods of time. In
contrast to the corresponding description of scalar particles, the structure of
nonequilibrium fermion propagators exhibits features which have no counterpart
in the equilibrium theory.

</DOC>
<DOC>
<DOCNO> 69160 </DOCNO>
CP Violation and Dark Matter


  A brief review is given of the effects of CP violation on the direct
detection of neutralinos in dark matter detectors. We first summarize the
current developments using the cancellation mechanism which allows for the
existence of large CP violating phases consistent with experimental limits on
the electron and on the neutron electric dipole moments in a broad class of
SUSY, string and D brane models. We then discuss their effects on the
scattering of neutralinos from quarks and on the event rates. It is found that
while CP effects on the event rates can be enormous such effects are reduced
significantly with the imposition of the EDM constraints. However, even with
the inclusion of the EDM constraints the effects are still very significant and
should be included in a precision prediction of event rates in any SUSY, string
or D brane model.

</DOC>
<DOC>
<DOCNO> 101706 </DOCNO>
H^1 n'a pas de base compl\`etement inconditionnelle


  Let H^1 be the classical Hardy space of analytic functions on the unit disc.
We show that this space does not admit any finite rank completely unconditional
decomposition of the identity.

</DOC>
<DOC>
<DOCNO> 178596 </DOCNO>
ISI/FSI in Threshold Meson Production - Onshell Approach and Coulomb


  The onshell description of Initial- and Final-State-Interactions (ISI and
FSI) of threshold meson production reactions is reviewed. Existing onshell
models and their offshell extension are discussed. Unitarity constraints on
enhancement factors are formulated. A strategy for the treatment of essential
singularities connected to Coulomb-like FSI is given.

</DOC>
<DOC>
<DOCNO> 151791 </DOCNO>
U-duality Between NCOS Theory and Matrix Theory


  We show that the NCOS (noncommutative open string) theories on torus $T^p$
($p\leq 5$) are U-dual to matrix theory on torus with electric flux background.
Under U-duality, the number of D-branes and the number of units of electric
flux get interchanged. Furthermore under the same U-duality the decoupling
limit taken in the NCOS theory maps to the decoupling limit taken in the matrix
theory, thus ensure the U-duality between those two class of theories. We
consider the energy needed for Higgsing process and some bound states with
finite energy and find agreements in both theories.

</DOC>
<DOC>
<DOCNO> 116313 </DOCNO>
Spatiotemporally Localized Multidimensional Solitons in Self-Induced


  "Light bullets" are multi-dimensional solitons which are localized in both
space and time. We show that such solitons exist in two- and three-dimensional
self-induced-transparency media and that they are fully stable. Our approximate
analytical calculation, backed and verified by direct numerical simulations,
yields the multi-dimensional generalization of the one-dimensional Sine-Gordon
soliton.

</DOC>
<DOC>
<DOCNO> 100801 </DOCNO>
Fusion rules for the charge conjugation orbifold


  We completely determine the fusion rules for the vertex operator algebra
$V_L^+$ for a rank one even lattice $L$.

</DOC>
<DOC>
<DOCNO> 170609 </DOCNO>
Dipole Blockade and Quantum Information Processing in Mesoscopic Atomic


  We describe a technique for manipulating quantum information stored in
collective states of mesoscopic ensembles. Quantum processing is accomplished
by optical excitation into states with strong dipole-dipole interactions. The
resulting ``dipole blockade'' can be used to inhibit transitions into all but
singly excited collective states. This can be employed for a controlled
generation of collective atomic spin states as well as non-classical photonic
states and for scalable quantum logic gates. An example involving a cold
Rydberg gas is analyzed.

</DOC>
<DOC>
<DOCNO> 13853 </DOCNO>
A Few Properties of Disordered Conductors


  In this brief tutorial review, I show how phase coherent properties of
disordered conductors can be described in a simple and unified way. These
properties include transport properties like weak-localization correction and
universal conductance fluctuations, and thermodynamic properties like orbital
magnetism and persistent currents. They can be related to the classical return
probability for a diffusive particle. For a network with $N$ nodes, the return
probability can be related to the determinant of a $N \times N$ "connectivity"
matrix $M$ so that the magnetization and the transport quantities can be {\it
directly} written in term of $\det M$.

</DOC>
<DOC>
<DOCNO> 151185 </DOCNO>
Moduli spaces of maximally supersymmetric solutions on noncommutative


  A maximally supersymmetric configuration of super Yang-Mills living on a
noncommutative torus corresponds to a constant curvature connection. On a
noncommutative toroidal orbifold there is an additional constraint that the
connection be equivariant. We study moduli spaces of (equivariant) constant
curvature connections on noncommutative even-dimensional tori and on toroidal
orbifolds. As an illustration we work out the cases of Z_{2} and Z_{4}
orbifolds in detail. The results we obtain agree with a commutative picture
describing systems of branes wrapped on cycles of the torus and branes stuck at
exceptional orbifold points.

</DOC>
<DOC>
<DOCNO> 11933 </DOCNO>
Hall Coefficient of a Dilute 2D Electron System in Parallel Magnetic


  Measurements in magnetic fields applied at a small angle with respect to the
2D plane of the electrons of a low-density silicon MOSFET indicate that the
Hall coefficient is independent of parallel field from H=0 to $H>H_{sat}$, the
field above which the longitudinal resistance saturates and the electrons have
reached full spin-polarization. This implies that the mobilities of the spin-up
and spin-down electrons remain comparable at all magnetic fields, and suggests
there is strong mixing of spin-up and spin-down electron states.

</DOC>
<DOC>
<DOCNO> 99640 </DOCNO>
On the combinatorics of Forrester-Baxter models


  We provide further boson-fermion q-polynomial identities for the `finitised'
Virasoro characters \chi^{p, p'}_{r,s} of the Forrester-Baxter minimal models
M(p, p'), for certain values of r and s. The construction is based on a
detailed analysis of the combinatorics of the set P^{p, p'}_{a, b, c}(L) of
q-weighted, length-L Forrester-Baxter paths, whose generating function \chi^{p,
p'}_{a, b, c}(L) provides a finitisation of \chi^{p, p'}_{r,s}. In this paper,
we restrict our attention to the case where the startpoint a and endpoint b of
each path both belong to the set of Takahashi lengths. In the limit L ->
infinity, these polynomial identities reduce to q-series identities for the
corresponding characters.

</DOC>
<DOC>
<DOCNO> 68215 </DOCNO>
A short course in effective Lagrangians


  These lectures provide an introduction to effective theories concentrating on
the basic ideas and providing some simple applications

</DOC>
<DOC>
<DOCNO> 120452 </DOCNO>
UV Observations of the Powering Source of the Supergiant Shell in IC2574


  A multi-band analysis of the region containing the supergiant HI shell in the
nearby dwarf irregular galaxy IC2574 presents evidence of a causal relationship
between a central star cluster, the surrounding expanding HI shell, and
secondary star formation sites on the rim of the HI shell. Comparisons of the
far-UV (FUV, 1521 A), optical broad-band, H-alpha, X-ray, and HI morphologies
suggest that the region is in an auspicious moment of star formation triggered
by the central stellar cluster. The derived properties of the HI shell, the
central stellar cluster, and the star forming regions on the rim support this
scenario: The kinematic age of the HI shell is <14 Myr and in agreement with
the age of the central stellar cluster derived from the FUV observations (sim
11 Myr). An estimate for the mechanical energy input from SN and stellar winds
of the central stellar cluster made from FUV photometry and the derived cluster
age is 4.1 x 10^52 erg, roughly a few times higher than the kinetic energy of
the HI shell. The requisite energy input needed to create the HI shell, derived
in the `standard' fashion from the HI observations (using the numerical models
of Chevalier), is 2.6 x 10^53 erg which is almost an order of magnitude higher
than the estimated energy input as derived from the FUV data. Given the
overwhelming observational evidence that the central cluster is responsible for
the expanding HI shell, this discrepancy suggests that the required energy
input is overestimated using the `standard' method. This may explain why some
other searches for remnant stellar clusters in giant HI holes have been
unsuccessful so far. Our observations also show that stellar clusters are
indeed able to create supergiant HI shells, even at large galactocentric radii,
a scenario which has recently been questioned by a number of authors.

</DOC>
<DOC>
<DOCNO> 120901 </DOCNO>
Magnetic Fields and the Triaxiality of Molecular Cloud Cores


  We make the hypothesis that molecular cloud fragments are triaxial bodies
with a large scale magnetic field oriented along the short axis. While
consistent with theoretical expectations, this idea is supported by magnetic
field strength data, which show strong evidence for flattening along the
direction of the mean magnetic field. It is also consistent with early
submillimeter polarization data, which show that the projected direction of the
magnetic field is often slightly misaligned with the projected minor axis of a
molecular cloud core, i.e., the offset angle $\Psi$ is nonzero. We calculate
distributions of $\Psi$ for various triaxial bodies, when viewed from a random
set of viewing angles. The highest viewing probability always corresponds to
$\Psi=0^{\circ}$, but there is a finite probability of viewing all nonzero
$\Psi$, including even $\Psi =90^{\circ}$; the average offset typically falls
in the range $10^{\circ}-30^{\circ}$ for triaxial bodies most likely to satisfy
observational and theoretical constraints.

</DOC>
<DOC>
<DOCNO> 85309 </DOCNO>
From ADM to Brane-World charges


  We first recall a covariant formalism used to compute conserved charges in
gauge invariant theories. We then study the case of gravity for two different
boundary conditions, namely spatial infinity and a Brane-World boundary. The
new conclusion of this analysis is that the gravitational energy (and linear
and angular momentum) is a local expression if our universe is really a
boundary of a five-dimensional spacetime.

</DOC>
<DOC>
<DOCNO> 40647 </DOCNO>
Deep-Inelastic Inclusive ep Scattering at Low x and a Determination of


  A precise measurement of the inclusive deep-inelastic e^+p scattering cross
section is reported in the kinematic range 1.5<= Q^2 <=150 GeV^2 and
3*10^(-5)<= x <=0.2. The data were recorded with the H1 detector at HERA in
1996 and 1997, and correspond to an integrated luminosity of 20 pb^(-1). The
double differential cross section, from which the proton structure function
F_2(x,Q^2) and the longitudinal structure function F_L(x,Q^2) are extracted, is
measured with typically 1% statistical and 3% systematic uncertainties. The
measured partial derivative (dF_2(x,Q^2)/dln Q^2)_x is observed to rise
continuously towards small x for fixed Q^2. The cross section data are combined
with published H1 measurements at high Q^2 for a next-to-leading order DGLAP
QCD analysis.The H1 data determine the gluon momentum distribution in the range
3*10^(-4)<= x <=0.1 to within an experimental accuracy of about 3% for Q^2 =20
GeV^2. A fit of the H1 measurements and the mu p data of the BCDMS
collaboration allows the strong coupling constant alpha_s and the gluon
distribution to be simultaneously determined. A value of alpha
_s(M_Z^2)=0.1150+-0.0017 (exp) +0.0009-0.0005 (model) is obtained in NLO, with
an additional theoretical uncertainty of about +-0.005, mainly due to the
uncertainty of the renormalisation scale.

</DOC>
<DOC>
<DOCNO> 99539 </DOCNO>
Degenerations of Mixed Hodge structure


  We continue our work on variations of graded-polarized mixed Hodge structures
by defining analogs of the harmonic metric equations for filtered bundles and
proving a precise analog of Schmid's Nilpotent Orbit Theorem for 1-parameter
degenerations of graded-polarized mixed Hodge structure.

</DOC>
<DOC>
<DOCNO> 151921 </DOCNO>
CFT Description of Small Objects in AdS


  By the AdS/CFT correspondence, the expectation value of certain local
operators in the CFT is given by the asymptotic value of supergravity fields.
We show that these local expectation values contain a remarkable amount of
information about small sources deep inside AdS_p x S^q. In particular, they
contain essentially all the multipole moments. More importantly, one can use
them to determine the size of a spherical source. This is not a small effect:
The size appears in an exponentially large contribution to the expectation
values. This provides an easy way for the CFT to distinguish stars from black
holes with the same mass, or to distinguish different "giant graviton"
configurations.

</DOC>
<DOC>
<DOCNO> 67998 </DOCNO>
Neutralino Proton Cross Sections In Supergravity Models


  The neutralino-proton cross section is examined for supergravity models with
R-parity invariance with universal and non-universal soft breaking. The region
of parameter space that dark matter detectors are currently (or will be
shortly) sensitive i.e. $(0.1-10)\times 10^{-6}$ pb, is examined. For universal
soft breaking (mSUGRA), detectors with sensitivity
$\sigma_{\tilde{\chi}_{1}^{0}-p} \geq 1 \times 10^{-6}$ pb will be able to
sample parts of the parameter space for $\tan \beta \stackrel{>}{\sim} 25$.
Current relic density bounds restrict $m_{\tilde{\chi}_{1}^{0}} \leq 120$ GeV
for the maximum cross sections, which is below where astronomical uncertainties
about the Milky Way are relevant. Nonuniversal soft breaking models can allow
much larger cross sections and can sample the parameter space for $\tan \beta
\stackrel{>}{\sim} 4$. In such models, $m_0$ can be quite large reducing the
tension between proton decay bounds and dark matter analysis. We note the
existance of two new domains where coannihilation effects can enter, i.e. for
mSUGRA at large $\tan \beta$, and for nonuniversal models with small $\tan
\beta$.

</DOC>
<DOC>
<DOCNO> 71365 </DOCNO>
QCD Theory at High Energy


  The energy range and quality of strong-interaction data from recent years
demand the study of higher orders in perturbative QCD, and of nonperturbative
effects. I discuss a selection of recent progress in the theory of QCD at high
energy, including examples from perturbative resummation, nonperturbative power
corrections and the Regge limit. In each case, techniques of factorization play
a central role.

</DOC>
<DOC>
<DOCNO> 39935 </DOCNO>
Precise Measurement of $B^{0}\to \bar{B^{0}$ Mixing Parameters at the


  We describe a measurement of B^0-B^0bar mixing parameters exploiting a method
of partial reconstruction of the decay chains B0 -> D^{*-}\pi^+ and B0 ->
D^{*-}\rho^+. Using 9.6 x 10^6 BBbar pairs collected at the Cornell Electron
Storage Ring, we find \chi_d = 0.198 +- 0.013 +- 0.014, |y_d|<0.41 at 95%
confidence level, and |Re(\epsilon_B)|<0.034 at 95% confidence level.

</DOC>
<DOC>
<DOCNO> 117608 </DOCNO>
Comprehensive analytic formulae for stellar evolution as a function of


  We present analytic formulae that approximate the evolution of stars for a
wide range of mass and metallicity. Stellar luminosity, radius and core mass
are given as a function of age, M and Z, for all phases from the zero-age
main-sequence up to, and including, the remnant stages. For the most part we
find continuous formulae accurate to within 5% of detailed models. These
formulae are useful for purposes such as population synthesis that require very
rapid but accurate evaluation of stellar properties, and in particular for use
in combination with N-body codes. We describe a mass loss prescription that can
be used with these formulae and investigate the resulting stellar remnant
distribution.

</DOC>
<DOC>
<DOCNO> 150707 </DOCNO>
W-symmetries on the Homogeneous Space G/U(1)^r


  A construction of $W$-symmetries is given only in terms of the nonlocal
fields (parafermions ${\ps}_{\al}$), which take values on the homogeneous space
$G/U(1)^r$, where $G$ is a simply connected compact Lie group manifold (its
accompanying Lie algebra ${\cal G}$ is a simple one of rank $r$). Only certain
restriction of the root set of Lie algebra on which the parafermionic fields
take values are satisfied, then a consistent and non-trivial extension of the
stress momentum tensor may exist. For arbitrary simple-laced algebras, i.e. the
$A-D-E$ cases, a more detailed discussion is given. The OPE of spin three
primary field are calculated, in which a primary field with spin four is
emerging.

</DOC>
<DOC>
<DOCNO> 100432 </DOCNO>
Generating-function method for tensor products


  This is the first of two articles devoted to a exposition of the
generating-function method for computing fusion rules in affine Lie algebras.
The present paper is entirely devoted to the study of the tensor-product
(infinite-level) limit of fusions rules.
  We start by reviewing Sharp's character method. An alternative approach to
the construction of tensor-product generating functions is then presented which
overcomes most of the technical difficulties associated with the character
method. It is based on the reformulation of the problem of calculating tensor
products in terms of the solution of a set of linear and homogeneous
Diophantine equations whose elementary solutions represent ``elementary
couplings''. Grobner bases provide a tool for generating the complete set of
relations between elementary couplings and, most importantly, as an algorithm
for specifying a complete, compatible set of ``forbidden couplings''.

</DOC>
<DOC>
<DOCNO> 119515 </DOCNO>
A Look at What Is (and Isn't) Known About Quasar Broad Line Regions and


  The evidence is reviewed that the Broad Line Region (BLR) probably has two
distinct components located at about the same distance from the central black
hole. One component, BLR II, is optically-thick, low-ionization emission at
least some of which arises from a disc and the other, BLR I, is probably
optically-thin emission from a more spherically symmetric halo or atmosphere.
The high Fe II/H-beta ratios seen in Narrow-Line Seyfert 1 galaxies (NLS1s) are
not due to strong Fe II emission, as is commonly thought, but to unusually weak
Balmer emission, probably caused by higher densities. NLS1s probably differ
from non-NLS1s because of the higher density of gas near the black hole. This
produces a higher accretion rate, a denser BLR, and a view of the central
regions that is more face-on.

</DOC>
<DOC>
<DOCNO> 100477 </DOCNO>
Supersymmetry and Homotopy


  The homotopical information hidden in a supersymmetric structure is revealed
by considering deformations of a configuration manifold. This is in sharp
contrast to the usual standpoints such as Connes' programme where a geometrical
structure is rigidly fixed. For instance, we can relate supersymmetries of
types N=2n and N=(n, n) in spite of their gap due to distinction between
$\Bbb{Z}_2$(even-odd)- and integer-gradings.
  Our approach goes beyond the theory of real homotopy due to Quillen, Sullivan
and Tanr\'e developed, respectively, in the 60's, 70's and 80's, which exhibits
real homotopy of a 1-connected space out of its de Rham-Fock complex with
supersymmetry. Our main new step is based upon the Taylor (super-)expansion and
locality, which links differential geometry with homotopy without the
restriction of 1-connectedness. While the homotopy invariants treated so far in
relation with supersymmetry are those depending only on $\Bbb{Z}_2$-grading
like the index, here we can detect new $\Bbb{N}$-graded homotopy invariants.
While our setup adopted here is (graded) commutative, it can be extended also
to the non-commutative cases in use of state germs (Haag-Ojima) corresponding
to a Taylor expansion.

</DOC>
<DOC>
<DOCNO> 116504 </DOCNO>
Hyperfine spectra of CH3F nuclear spin conversion


  A theoretical model of hyperfine spectra of nuclear spin conversion of
molecular isomers has been developed. The model takes into account the nuclear
spin-spin and spin-rotation interactions, as well as the saturation of
intramolecular mixing of molecular ortho and para states. The model has been
applied to hyperfine spectra of nuclear spin conversion in ^{13}CH3F molecules
subjected to an external electric field. Conditions under which the hyperfine
structure in the spectra can be resolved have been determined.

</DOC>
<DOC>
<DOCNO> 121453 </DOCNO>
Cosmological parameters from observational data on the large scale


  The observational data on the large scale structure (LSS) of the Universe are
used to determine cosmological parameters within the class of adiabatic
inflationary models. We show that a mixed dark matter model with cosmological
constant ($\Lambda$MDM model) and parameters $\Omega_m=0.37^{+0.25}_{-0.15}$,
$\Omega_{\Lambda}=0.69^{+0.15}_{-0.20}$, $\Omega_{\nu}=0.03^{+0.07}_{-0.03}$,
$N_{\nu}=1$, $\Omega_b=0.037^{+0.033}_{-0.018}$, $n_s=1.02^{+0.09}_{-0.10}$,
$h=0.71^{+0.22}_{-0.19}$, $b_{cl}=2.4^{+0.7}_{-0.7}$ (1$\sigma$ confidence
limits) matches observational data on LSS, the nucleosynthesis constraint,
direct measurements of the Hubble constant, the high redshift supernova type Ia
results and the recent measurements of the location and amplitude of the first
acoustic peak in the CMB anisotropy power spectrum. The best model is $\Lambda$
dominated (65% of the total energy density) and has slightly positive
curvature, $\Omega=1.06$. The clustered matter consists in 8% massive
neutrinos, 10% baryons and 82% cold dark matter (CDM). It is shown that the LSS
observations together with the Boomerang (+MAXIMA-1) data on the first acoustic
peak rule out zero-$\Lambda$ models at more than $2\sigma$ confidence level.

</DOC>
<DOC>
<DOCNO> 122559 </DOCNO>
HST-NICMOS Observations of M31's Metal Rich Globular Clusters and Their


  We have obtained HST-NICMOS observations of five of M31's most metal rich
globular clusters. These data allow photometry of individual stars in the
clusters and their surrounding fields. However, to achieve our goals -- obtain
accurate luminosity functions to compare with their Galactic counterparts,
determine metallicities from the slope of the giant branch, identify long
period variables, and estimate ages from the AGB tip luminosity, we must be
able to disentangle the true properties of the population from the
observational effects associated with measurements made in very crowded fields.
  In this paper we present a careful analysis of photometry in crowded regions,
and show how image blending affects the results and interpretation of such
data. Although this analysis is specifically for our NICMOS observations in
M31, the techniques we develop can be applied to any imaging data taken in
crowded fields; we show how the effects of image blending will even limit NGST.
We use three different techniques to analyze the effects of crowding on our
data, including the insertion of artificial stars (traditional completeness
tests) and the creation of completely artificial clusters. They are used to
derive threshold- and critical-blending radii for each cluster, which determine
how close to the cluster center reliable photometry can be achieved. The
simulations also allow us to quantify and correct for the effects of blending
on the slope and width of the RGB at different surface brightness levels.

</DOC>
<DOC>
<DOCNO> 11200 </DOCNO>
Thermodynamical implications of a protein model with water interactions


  We refine a protein model that reproduces fundamental aspects of protein
thermodynamics. The model exhibits two transitions, hot and cold unfolding. The
number of relevant parameters is reduced to three: 1) binding energy of folding
relative to the orientational energy of bound water, 2) ratio of degrees of
freedom between the folded and unfolded protein chain and 3) the number of
water molecules that can access the hydrophobic parts of the protein interior.
By increasing the number of water molecules in the model, the separation
between the two peaks in the heat capacity curve decreases, which is more
consistent with experimental data. We also show that if we, as a speculative
assumption, assign effectively only two distinct energy levels for the bound
water molecules, the hot peak in the heat capacity curve will be larger than
the cold peak, in accordance with experimental observations.

</DOC>
<DOC>
<DOCNO> 84411 </DOCNO>
Self-similar spherically symmetric cosmological models with a perfect


  Self-similar, spherically symmetric cosmological models with a perfect fluid
and a scalar field with an exponential potential are investigated. New
variables are defined which lead to a compact state space, and dynamical
systems methods are utilised to analyse the models. Due to the existence of
monotone functions global dynamical results can be deduced. In particular, all
of the future and past attractors for these models are obtained and the global
results are discussed. The essential physical results are that initially
expanding models always evolve away from a massless scalar field model with an
initial singularity and, depending on the parameters of the models, either
recollapse to a second singularity or expand forever towards a flat power-law
inflationary model. The special cases in which there is no barotropic fluid and
in which the scalar field is massless are considered in more detail in order to
illustrate the asymptotic results. Some phase portraits are presented and the
intermediate dynamics and hence the physical properties of the models are
discussed.

</DOC>
<DOC>
<DOCNO> 122256 </DOCNO>
Modelling the Interstellar Medium of Low Surface Brightness Galaxies:


  We use a combination of three-dimensional Monte Carlo radiative transfer
techniques and multi-wavelength (BRHK,H alpha) imaging data to investigate the
nature of the interstellar medium (ISM) in the edge-on, low surface brightness
(LSB) galaxy UGC7321. Using realistic models that incorporate multiple
scattering effects and clumping of the stars and the interstellar material, we
explore the distribution and opacity of the interstellar material (gas+dust),
and its effects on the observed stellar disk luminosity profiles, color
gradients, and rotation curve shape. We find that UGC7321 contains a small but
non-negligible dusty component to its ISM, yielding a B-band optical depth
tau_e,B~4.0 from disk edge to center. A significant fraction (~50+/-10%) of the
interstellar material in the innermost regions of UGC7321 appears to be
contained in a clumpy medium, indicating that LSB galaxies can support a
modest, multi-phase ISM structure. In spite of the clear presence of dust, we
conclude that the large radial optical color gradients observed in UGC7321 and
other similar LSB spiral galaxies cannot be accounted for by dust and must
result primarily from significant stellar population and/or metallicity
gradients. We show that realistic optical depth effects will have little impact
on the observed rotation curves of edge-on disk galaxies and cannot explain the
linear, slowly rising rotation curves seen in some edge-on LSB spirals.
Projection effects create a far larger uncertainty in recovering the true
underlying rotation curve shape of galaxies viewed at inclinations i>85
degrees.

</DOC>
<DOC>
<DOCNO> 120913 </DOCNO>
Search for High Energy Neutrino Emission from Gamma-Ray Bursts with the


  The photo-meson production of pions by shock-accelerated protons could
generate a burst of ~10^14 eV neutrinos from gamma-ray bursts (GRBs) observable
in the Antarctic Muon and Neutrino Detector Array (AMANDA) or its larger
successors. Measurement of this flux can test the hypothesis that GRBs are the
sources of the highest-energy cosmic rays, and GRB neutrinos could permit
high-precision experiments in neutrino limiting speed, neutrino oscillations,
and the weak equivalence principle. Neutrino emission can be expected primarily
during the prompt gamma-ray flash and satellite coincidence provides a
well-defined window in position and time that can be searched for an excess of
upgoing muon events in AMANDA from bursts in the Northern Hemisphere. Using an
event quality analysis to further reduce background in a sample of 78 GRBs from
the 1997 AMANDA-B10 data set, I find a fluence limit of (E_nu)^2
(dN_nu)/(dE_nu)<3.8*10^-4 min(1,E_nu/E_break) [TeV cm^-2] per average burst,
which is orders of magnitude more stringent than in similar previous searches.

</DOC>
<DOC>
<DOCNO> 119817 </DOCNO>
Tunable Imaging Filters in Astronomy


  While tunable filters are a recent development in night time astronomy, they
have long been used in other physical sciences, e.g. solar physics, remote
sensing and underwater communications. With their ability to tune precisely to
a given wavelength using a bandpass optimized for the experiment, tunable
filters are already producing some of the deepest narrowband images to date of
astrophysical sources. Furthermore, some classes of tunable filters can be used
in fast telescope beams and therefore allow for narrowband imaging over angular
fields of more than a degree over the sky.

</DOC>
<DOC>
<DOCNO> 118609 </DOCNO>
Lower Limit on Radius as a Function of Mass for Neutron Stars


  While model-independent limits are always interesting, a limit on neutron
star radius as a function of mass attains special interest in light of recent
interpretations of the periodic as well as quasi-periodic oscillations (QPOs)
in brightness of X-rays emitted from neutron stars that are accreting matter
from a low-mass companion. Here we derive such a limit based only on well
accepted principles. We discuss our limit in connection with a recent
interpretation of X-ray pulsations from SAX J1808.4-3658 as indicating a
strange-star candidate, and show that this object can also be a normal neutron
star, though one whose central core has very high density. The most plausible
high-density phase of hadronic matter, which is also expected to be very
compressible, is quark matter. So an alternative to the strange star
interpretation of SAX J1808.4-3658 is that it is a hybrid neutron star.

</DOC>
<DOC>
<DOCNO> 10348 </DOCNO>
Adsorption on a periodically corrugated substrate


  Mean field analysis of the effective interfacial Hamiltonian shows that with
increasing temperature the adsorption on a periodically corrugated substrate
can proceed in two steps: first, there is the filling transition in which the
depressions of the substrate become partially or completely filled; then there
is the wetting transition at which the substrate as a whole becomes covered
with a macroscopically thick wetting layer. The actual order and location of
both transitions are related to the wetting properties of the corresponding
planar substrate and to the form of corrugation. Certain morphological
properties of the liquid-vapor interface in the case of a saw-like corrugated
substrate are discussed analytically

</DOC>
<DOC>
<DOCNO> 68269 </DOCNO>
J/Psi suppression in an expanding equilibrium hadron gas


  We consider an ideal gas of massive hadrons in thermal and chemical
equilibrium. The finite-size gas expands longitudinally in accordance with
Bjorken law. Also the transverse expansion in a form of the rarefaction wave is
considered. We show that J/Psi suppression in such an environment, when
combined with the disintegration in nuclear matter, agrees qualitatively well
with NA38 and NA50 data.

</DOC>
<DOC>
<DOCNO> 116784 </DOCNO>
A Simple Model for the Non-Retarded Dispersive Force between an


  It is well known that for the case of two neutral but electrically
polarizable atoms the consideration or not of retardation effects on the
dispersive van der Waals force between them leads essentially to different
power laws for the forces; while the retarded force is proportional to $1/r^8$,
where $r$ is the distance between the atoms, the non-retarded force is
proportional to $1/r^7$. Here we consider the (repulsive) dispersive force
between an electrically polarizable atom and a magnetically polarizable one and
show that, in contrast to the previous case, a quite unexpected result appears,
namely: while the retarded force is still proportional to $1/r^8$, the
non-retarded force is proportional to $1/r^5$. We employ a semiclassical method
based on the fluctuating dipole model for both atoms.

</DOC>
<DOC>
<DOCNO> 150896 </DOCNO>
BPS Saturated Vacua Interpolation along One Compact Dimension


  A class of generalized Wess-Zumino models with distinct vacua is
investigated. These models allow for BPS saturated vacua interpolation along
one compact spatial dimension. The properties of these interpolations are
studied.

</DOC>
<DOC>
<DOCNO> 84213 </DOCNO>
Conservation of Circulation in Magnetohydrodynamics


  We demonstrate, both at the Newtonian and (general) relativistic levels, the
existence of a generalization of Kelvin's circulation theorem (for pure fluids)
which is applicable to perfect magnetohydrodynamics. The argument is based on
the least action principle for magnetohydrodynamic flow. Examples of the new
conservation law are furnished. The new theorem should be helpful in
identifying new kinds of vortex phenomena distinct from magnetic ropes or fluid
vortices.

</DOC>
<DOC>
<DOCNO> 117895 </DOCNO>
An analytic model for the epoch of halo creation


  In this paper we describe the Bayesian link between the cosmological mass
function and the distribution of times at which isolated halos of a given mass
exist. By assuming that clumps of dark matter undergo monotonic growth on the
time-scales of interest, this distribution of times is also the distribution of
`creation' times of the halos. This monotonic growth is an inevitable aspect of
gravitational instability. The spherical top-hat collapse model is used to
estimate the rate at which clumps of dark matter collapse. This gives the prior
for the creation time given no information about halo mass. Applying Bayes'
theorem then allows any mass function to be converted into a distribution of
times at which halos of a given mass are created. This general result covers
both Gaussian and non-Gaussian models. We also demonstrate how the mass
function and the creation time distribution can be combined to give a joint
density function, and discuss the relation between the time distribution of
major merger events and the formula calculated. Finally, we determine the
creation time of halos within three N-body simulations, and compare the link
between the mass function and creation rate with the analytic theory.

</DOC>
<DOC>
<DOCNO> 69516 </DOCNO>
gamma* N -> Delta transition form factors: a new analysis of the JLab


  Recent JLab data of the differential cross section for the reaction
p(e,e'p)pi0 in the invariant mass region of 1.1 < W < 1.4 GeV at four-momentum
transfer squared Q^2= 2.8 and 4.0 (GeV/c)$^2$ are analyzed with two models,
both of which give an excellent description of most of the existing pion
electroproduction data below W < 1.5 GeV. We find that at up to Q^2 =
4.0(GeV/c)^2, the extracted helicity amplitudes A_{3/2} and A_{/2} remain
comparable with each other, implying that hadronic helicity is not conserved at
this range of Q^2. The ratios E_{1+}/M_{1+} obtained show, starting from a
small and negative value at the real photon point, a clear tendency to cross
zero, and to become positive with increasing Q^2. This is a possible indication
of a very slow approach toward the pQCD region.Furthermore, we find that the
helicity amplitude A_{1/2} and S_{1/2}, but not A_{3/2}, starts exhibiting the
scaling behavior at about Q^2 \ge 2.5(GeV/c)^2.

</DOC>
<DOC>
<DOCNO> 7798 </DOCNO>
The Hentschel-Procaccia Conjecture


  Extensive confusion exists and persists in the literature on dynamical
systems theory, cosmology, and other fields over spectra of fractal dimensions.
Entirely different generating functions have been treated as if they should
yield identical spectra, or scaling exponents. An uncritical implicit
assumption of universality of scaling exponents is made, even though there is
no good theoretical reason to expect scaling exponents to be universal away
from criticality. Expectations based on the unphysical and empirically
inapplicable zero length scale limit (which would require infinite precision in
data analysis) are often taken for granted. A source of confusing together
different generating functions can be traced back to the Hentschel-Procaccia
conjecture, which I prove to be wrong for the case of data analysis in the only
applicable limit, that of finite precision. The two different definitions of
'multifractal' stated by Mandelbrot and by Halsey et are compared and
contrasted.

</DOC>
<DOC>
<DOCNO> 84833 </DOCNO>
The mathematical theory of resonant transducers in a spherical gravity


  The rigoruos mathematical theory of the coupling and response of a spherical
gravitational wave detector endowed with a set of resonant transducers is
presented and developed. A perturbative series in ascending powers of the
square root of the ratio of the resonator to the sphere mass is seen to be the
key to the solution of the problem. General layouts of arbitrary numbers of
transducers can be assessed, and a specific proposal (PHC), alternative to the
highly symmetric TIGA of Merkowitz and Johnson, is described in detail.
Frequency spectra of the coupled system are seen to be theoretically recovered
in full agreement with experimental determinations.

</DOC>
<DOC>
<DOCNO> 39882 </DOCNO>
Double beta decay with large scale Yb-loaded scintillators


  The potential of large scale Yb-loaded liquid scintillators as proposed for
solar neutrino spectroscopy are investigated with respect to double beta decay.
The potential for beta-beta- - decay of 176Yb as well as the beta+/EC - decay
for 168Yb is discussed. Not only getting for the first time an experimental
half-life limit on 176Yb - decay, this will even be at least comparable or
better than existing ones from other isotopes. Also for the first time a
realistic chance to detect beta+/EC - decay exists. Effects of MeV-neutrinos
are discussed as well.

</DOC>
<DOC>
<DOCNO> 71056 </DOCNO>
On the Significance of the Quantity "A Squared"


  We consider the gauge potential A and argue that the minimum value of the
volume integral of A squared (in Euclidean space) may have physical meaning,
particularly in connection with the existence of topological structures. A
lattice simulation comparing compact and non-compact ``photodynamics'' shows a
jump in this quantity at the phase transition, supporting this idea.

</DOC>
<DOC>
<DOCNO> 40287 </DOCNO>
Measurement of the Mass and Width of the W Boson in e+e- Collisions at


  The mass and width of the W boson are determined in e+e- collisions at LEP
using 183 pb^-1 of data recorded at a centre-of-mass energy roots=189 GeV with
the OPAL detector. The invariant mass distributions from 970 WW->qqqq and 1118
WW->qqln candidate events are used to measure the mass of the W boson,
  Mw = 80.451 +- 0.076(stat.) +- 0.049(syst.) GeV.
  A direct measurement of the width of the W boson gives Gw=2.09 +- 0.18(stat.)
+- 0.09(syst.) GeV. The results are combined with previous OPAL results from 78
pb^-1 of data recorded with roots from 161 to 183 GeV, to obtain:
  Mw = 80.432 +- 0.066(stat.) +- 0.045(syst.) GeV,
  Gw = 2.04 +- 0.16(stat.) +- 0.09(syst.) GeV.
  The consistency of the direct measurement of Mw with that inferred from other
measurements of electroweak parameters provides an important test of the
Standard Model of electroweak interactions.

</DOC>
<DOC>
<DOCNO> 119243 </DOCNO>
Magnetorotational Instability in Protoplanetary Disks. II. Ionization


  We investigate where in protoplanetary disks magnetorotational instability
operates, which can cause angular momentum transport in the disks. We
investigate the spatial distribution of various charged particles and the
unstable regions for a variety of models for protoplanetary disks taking into
account the recombination of ions and electrons at grain surfaces, which is an
important process in most parts of the disks. We find that for all the models
there is an inner region which is magnetorotationally stable due to ohmic
dissipation. This must make the accretion onto the central star non-steady. For
the model of the minimum-mass solar nebula, the critical radius, inside of
which the disk is stable, is about 20 AU, and the mass accretion rate just
outside the critical radius is 10^{-7} - 10^{-6} M_{\odot} yr^{-1}. The stable
region is smaller in a disk of lower column density. Dust grains in
protoplanetary disks may grow by mutual sticking and may sediment toward the
midplane of the disks. We find that the stable region shrinks as the grain size
increases or the sedimentation proceeds. Therefore in the late evolutionary
stages, protoplanetary disks can be magnetorotationally unstable even in the
inner regions.

</DOC>
<DOC>
<DOCNO> 8426 </DOCNO>
Evaluation of low-energy effective Hamiltonian techniques for coupled


  Motivated by recent work on Heisenberg antiferromagnetic spin systems on
various lattices made up of triangles, we examine the low-energy properties of
a chain of antiferromagnetically coupled triangles of half-odd-integer spins.
We derive the low-energy effective Hamiltonian to second order in the ratio of
the coupling J_2 between triangles to the coupling J_1 within each triangle.
The effective Hamiltonian contains four states for each triangle which are
given by the products of spin-1/2 states with the states of a pseudospin-1/2.
We compare the results obtained by exact diagonalization of the effective
Hamiltonian with those obtained for the full Hamiltonian using exact
diagonalization and the density-matrix renormalization group method. It is
found that the effective Hamiltonian is accurate only for the ground state for
rather low values of the ratio J_2 / J_1 and that too for the spin-1/2 case
with linear topology. The chain of spin-1/2 triangles shows interesting
properties like spontaneous dimerization and several singlet and triplet
excited states lying close to the ground state.

</DOC>
<DOC>
<DOCNO> 121253 </DOCNO>
The Best Observables from the Point of View of a Model Maker


  We select and discuss the best observables to be used to constrain models of
galactic chemical evolution. To this purpose, we discuss the observables in our
Galaxy, which is the best studied system, as well as in external galaxies.

</DOC>
<DOC>
<DOCNO> 120361 </DOCNO>
Changing Frequency Separation of Kilohertz Quasi-Periodic Oscillations


  Previous work on the sonic-point beat-frequency (SPBF) model of the kilohertz
quasi-periodic oscillations (QPOs) observed in the X-ray flux from neutron
stars in low-mass binary systems has shown that it naturally explains many
properties of these QPOs. These include the existence of just two principal
QPOs in a given source, the commensurability of the frequency separation \Dnu\
of the two kilohertz QPOs and the spin frequency \nus inferred from burst
oscillations, and the high frequencies, coherence, and amplitudes of these
QPOs. Here we show that the SPBF model predicts that \Dnu is less than but
close to \nus, consistent with the observed differences between \Dnu and \nus.
It also explains naturally the decrease in \Dnu with increasing QPO frequency
seen in some sources and the plateau in the QPO frequency--X-ray flux observed
in 4U 1820-30. The model fits well the QPO frequency behavior observed in Sco
X-1, 4U 1608-52, 4U 1728-34, and 4U 1820-30 (chisqdof = 0.4-2.1), giving masses
ranging from 1.59 to 2.0 Msun and spin rates ranging from 279 to 364 Hz. In the
SPBF model, the kilohertz QPOs are effects of strong-field gravity. Thus, if
the model is validated, the kilohertz QPOs can be used not only to determine
the properties of neutron stars but also to explore quantitatively general
relativistic effects in the strong-field regime.

</DOC>
<DOC>
<DOCNO> 117103 </DOCNO>
Relativistic corrections to the dipole polarizability of the ground


  The recently reported precise experimental determination of the dipole
polarizability of the H_2^+ molecular ion ground state [P.L. Jacobson, R.A.
Komara, W.G. Sturrus, and S.R. Lundeen, Phys. Rev. A 62, 012509 (2000)] reveals
a discrepancy between theory and experiment of about 0.0007a_0^3, which has
been attributed to relativistic and QED effects. In present work we analyze an
influence of the relativistic effects on the scalar dipole polarizability of an
isolated H_2^+ molecular ion. Our conclusion is that it accounts for only 1/5
of the measured discrepancy.

</DOC>
<DOC>
<DOCNO> 118475 </DOCNO>
Quintessence-like Dark Matter in Spiral Galaxies


  Through the geodesic analysis of a static and axially symmetric space time,
we present conditions on the state equation of an isotropic perfect fluid
$p=\omega d$, when it is considered as dark matter in spiral galaxies. The main
conclusion is that it can be an exotic fluid ($-1<\omega <-1/3$) as it is found
for Quintessence at cosmological scale.

</DOC>
<DOC>
<DOCNO> 118789 </DOCNO>
Large Magellanic Cloud Planetary Nebula Morphology: Probing Stellar


  Planetary Nebulae (PNe) in the Large Magellanic Cloud (LMC) offer the unique
opportunity to study both the Population and evolution of low- and
intermediate-mass stars, by means of the morphological type of the nebula.
Using observations from our LMC PN morphological survey, and including images
available in the HST Data Archive, and published chemical abundances, we find
that asymmetry in PNe is strongly correlated with a younger stellar Population,
as indicated by the abundance of elements that are unaltered by stellar
evolution (Ne, Ar, S). While similar results have been obtained for Galactic
PNe, this is the first demonstration of the relationship for extra-galactic
PNe. We also examine the relation between morphology and abundance of the
products of stellar evolution. We found that asymmetric PNe have higher
nitrogen and lower carbon abundances than symmetric PNe. Our two main results
are broadly consistent with the predictions of stellar evolution if the
progenitors of asymmetric PNe have on average larger masses than the
progenitors of symmetric PNe. The results bear on the question of formation
mechanisms for asymmetric PNe, specifically, that the genesis of PNe structure
should relate strongly to the Population type, and by inference the mass, of
the progenitor star, and less strongly on whether the central star is a member
of a close binary system.

</DOC>
<DOC>
<DOCNO> 119247 </DOCNO>
A New Analysis Method for Reconstructing the Arrival Direction of TeV


  We present a method of atmospheric Cherenkov imaging which reconstructs the
unique arrival direction of TeV gamma rays using a single telescope. The method
is derived empirically and utilizes several features of gamma-ray induced air
showers which determine, to a precision of 0.12 degrees, the arrival direction
of photons, on an event-by-event basis. Data from the Whipple Observatory's 10
m gamma-ray telescope is utilized to test selection methods based on source
location. The results compare these selection methods with traditional
techniques and three different camera fields of view. The method will be
discussed in the context of a search for a gamma-ray signal from a point source
located anywhere within the field of view and from regions of extended
emission.

</DOC>
<DOC>
<DOCNO> 150614 </DOCNO>
Non-Abelian Born-Infeld versus String Theory


  Motivated by the results of Hashimoto and Taylor, we perform a detailed study
of the mass spectrum of the non-abelian Born-Infeld theory, defined by the
symmetrized trace prescription, on tori with constant magnetic fields turned
on. Subsequently, we compare this for several cases to the mass spectrum of
intersecting D-branes. Exact agreement is found in only two cases: BPS
configurations on the four-torus and coinciding tilted branes. Finally we
investigate the fluctuation dynamics of an arbitrarily wrapped Dp-brane with
flux.

</DOC>
<DOC>
<DOCNO> 101638 </DOCNO>
On symmetric units in group algebras


  Let $U(KG)$ be the group of units of the group ring $KG$ of the group $G$
over a commutative ring $K$. The anti-automorphism $g\mapsto g\m1$ of $G$ can
be extended linearly to an anti-automorphism $a\mapsto a^*$ of $KG$. Let
$S_*(KG)=\{x\in U(KG) \mid x^*=x\}$ be the set of all symmetric units of
$U(KG)$. We consider the following question: for which groups $G$ and
commutative rings $K$ it is true that $S_*(KG)$ is a subgroup in $U(KG)$. We
answer this question when either a) $G$ is torsion and $K$ is a commutative
$G$-favourable integral domain of characteristic $p\geq 0$ or b) $G$ is
non-torsion nilpotent group and $KG$ is semiprime.

</DOC>
<DOC>
<DOCNO> 12850 </DOCNO>
Particle-Vortex Duality and the Modular Group: Applications to the


  We show how particle-vortex duality implies the existence of a large
non-abelian discrete symmetry group which relates the electromagnetic response
for dual two-dimensional systems in a magnetic field. For conductors with
charge carriers satisfying Fermi statistics (or those related to fermions by
the action of the group), the resulting group is known to imply many, if not
all, of the remarkable features of Quantum Hall systems. For conductors with
boson charge carriers (modulo group transformations) a different group is
predicted, implying equally striking implications for the conductivities of
these systems, including a super-universality of the critical exponents for
conductor/insulator and superconductor/insulator transitions in two dimensions
and a hierarchical structure, analogous to that of the quantum Hall effect but
different in its details. Our derivation shows how this symmetry emerges at low
energies, depending only weakly on the details of dynamics of the underlying
systems.

</DOC>
<DOC>
<DOCNO> 85141 </DOCNO>
The Nature of Singularity in Bianchi I Cosmological String Gravity Model


  We investigate Bianchi I cosmological model in the theory of a dilatonM field
coupled to gravity through a Gauss-Bonnet term. Two type ofM cosmological
singularity are distinguished. The former is analogous toM the Einstein gravity
singularity, the latter (which does not appear inM classical General
Relativity) occurs when the main determinant of theM system of field equations
vanishes. An analogy between the latterM cosmological singularity and the
singularity inside a black hole withM a dilatonic hair is discussed. Initial
conditions, leading to theseM two types of cosmological singularity are found
via numericalM integration of the equation of motion.

</DOC>
<DOC>
<DOCNO> 122309 </DOCNO>
Gravitino production in the warm inflationary scenario


  We estimate the production of gravitinos during and after the end of a period
of warm inflation, a model in which radiation is produced continuously as the
field rolls down the potential producing dissipation. We find that gravitino
production is efficient for models in the strong dissipation regime, with the
result that standard nucleosynthesis is disrupted unless the magnitude of the
inflaton potential is very small. Combining this with the constraint from the
thermal production of adiabatic density perturbations we find the dissipation
rate must be extraordinarily strong, or that the potential is very flat.

</DOC>
<DOC>
<DOCNO> 102668 </DOCNO>
On some Definite Integrals involving the Hurwitz Zeta function


  We establish a series of integral formulae involving the Hurwitz zeta
function. Applications are given to integrals of Bernoulli polynomials, log
Gamma(q) and log sin(q).

</DOC>
<DOC>
<DOCNO> 151211 </DOCNO>
Confinement, asymptotic freedom and renormalons in type 0 string duals


  Type 0B string theory has been proposed as the dual description of
non-supersymmetric SU(N) Yang-Mills theory coupled to six scalars, in four
dimensions. We study numerically and analytically the equations of motion of
type 0B gravity and we find RG trajectories of the dual theory that flow from
an asymptotically free UV regime to a confining IR regime. In the UV we find a
one-parameter family of solutions that approach asymptotically $AdS_5\times
S^5$ with a logarithmic flow of the coupling plus non-perturbative terms that
correctly reproduce all UV and IR renormalon singularities. The first UV
renormalon gives a contribution $\sim F_1(E)/E^2$ and we are able to predict
also the form of the function $F_1(E)$, which, from the YM side, corresponds to
summing all multiple-chain bubble graphs. The fact that the positions of the
renormalon singularities in the Borel plane come out correctly is a non-trivial
test of the conjectured duality.

</DOC>
<DOC>
<DOCNO> 150935 </DOCNO>
An Elementary Derivation of the Black-Hole Area-Entropy Relation in Any


  A straightforward two-line derivation of the Bekenstein-Hawking Area-Entropy
relation for Black-Holes in {\bf any} dimension is shown based on Shannon's
information theory and Clifford algebras required by the New Relativity
Principle.

</DOC>
<DOC>
<DOCNO> 101738 </DOCNO>
Canonical path integral quantization of Einstein's gravitational field


  The connection between the canonical and the path integral formulations of
Einstein's gravitational field is discussed using the Hamilton - Jacobi method.
Unlike conventional methods, it is shown that our path integral method leads to
obtain the measure of integration with no $\delta$- functions, no need to fix
any gauge and so no ambiguous deteminants will appear.

</DOC>
<DOC>
<DOCNO> 150411 </DOCNO>
On Action Functionals for Interacting Brane Systems


  We present an action functional and derive equations of motion for a coupled
system of a bosonic Dp--brane and an open string ending on the Dp-brane. With
this example we address the key issues of the recently proposed method
(hep-th/9905144, hep-th/9906041) for the construction of manifestly
supersymmetric action functionals for interacting superbrane systems. We
clarify, in particular, how the arbitrariness in sources localized on the
intersection is related to the standard description of the flat D-branes as
rigid planes where the string for endpoints 'live'.

</DOC>
<DOC>
<DOCNO> 67961 </DOCNO>
Superconducting cosmic strings as gamma ray burst engines


  Cusps of superconducting strings can serve as GRB engines. A powerful beamed
pulse of electromagnetic radiation from a cusp produces a jet of accelerated
particles, whose propagation is terminated by the shock responsible for GRB. A
single free parameter, the string scale of symmetry breaking $\eta \sim 10^{14}
GeV$, together with reasonable assumptions about the magnitude of cosmic
magnetic fields and the fraction of volume that they occupy, explains the GRB
rate, duration and fluence, as well as the observed ranges of these quantities.
The wiggles on the string can drive the short-time structures of GRB. This
model predicts that GRBs are accompanied by strong bursts of gravitational
radiation which should be detectable by LIGO, VIRGO and LISA detectors.

</DOC>
<DOC>
<DOCNO> 122898 </DOCNO>
The Luminosity Function of Galaxies in SDSS Commissioning Data


  During commissioning observations, the Sloan Digital Sky Survey (SDSS) has
produced one of the largest existing galaxy redshift samples selected from CCD
images. Using 11,275 galaxies complete to r^* = 17.6 over 140 square degrees,
we compute the luminosity function of galaxies in the r^* band over a range -23
< M < -16 (for h=1). The result is well-described by a Schechter function with
parameters phi_* = 0.0146 +/- 0.0012 h^3 Mpc^{-3}, M_* = -20.83 +/- 0.03, and
alpha = -1.20 +/- 0.03. The implied luminosity density in r^* is j = (2.6 +/-
0.3) x 10^8 h L_sun Mpc^{-3}. The surface brightness selection threshold has a
negligible impact for M < -18. We measure the luminosity function in the u^*,
g^*, i^*, and z^* bands as well; the slope at low luminosities ranges from
alpha=-1.35 to alpha=-1.2. We measure the bivariate distribution of r^*
luminosity with half-light surface brightness, intrinsic color, and morphology.
High surface brightness, red, highly concentrated galaxies are on average more
luminous than low surface brightness, blue, less concentrated galaxies. If we
synthesize results for R-band or b_j-band using the Petrosian magnitudes with
which the SDSS measures galaxy fluxes, we obtain luminosity densities 2.0 times
that found by the Las Campanas Redshift Survey in R and 1.4 times that found by
the Two-degree Field Galaxy Redshift Survey in b_j. We are able to reproduce
the luminosity functions obtained by these surveys if we also mimic their
isophotal limits for defining galaxy magnitudes, which are shallower and more
redshift dependent than the Petrosian magnitudes used by the SDSS. (Abridged)

</DOC>
<DOC>
<DOCNO> 101880 </DOCNO>
Poisson and Hamiltonian Superpairs over Polarized Associative Algebras


  Poisson superpair is a pair of Poisson superalgebra structures on a super
commutative associative algebra, whose any linear combination is also a Poisson
superalgebra structure. In this paper, we first construct certain linear and
quadratic Poisson superpairs over a finite-dimensional or
semi-finitely-filtered polarized $\Bbb{Z}_2$-graded associative algebra. Then
we give a construction of certain Hamiltonian superpairs in the formal
variational calculus over any finite-dimensional $\Bbb{Z}_2$-graded associative
algebra with a supersymmetric nondegenerate associative bilinear form. Our
constructions are based on the Adler mapping in a general sense. Our works in
this paper can be viewed as noncommutative generalizations of the
Adler-Gel'fand-Dikii Hamiltonian pair. As a preparatory work, some structural
properties of polarized associative algebras have been studied.

</DOC>
<DOC>
<DOCNO> 117661 </DOCNO>
Infrared Imaging of z=2.43 Radio Galaxy B3 0731+438 with the Subaru


  We report on infrared imaging observations of the z=2.429 radio galaxy B3
0731+438 with the Subaru telescope. The images were taken with the K'-band
filter and the 2.25 um narrow-band filter to examine the structure and
properties of the Ha+[N II] 6548,6583 emission-line components. The Ha+[N II]
emission-line image shows biconical lobes with an extent of 40 kpc, which are
aligned with the radio axis. The rest-frame equivalent widths of the emission
lines at these cones are as large as 1100 AA, and can be well explained by a
gas-cloud model photoionized by power-law continuum radiation. The isotropic
ionizing photon luminosity necessary to ionize the hydrogen gas in these cones
amounts to 1e57(photons/s), which is larger than that in the majority of
radio-loud QSOs. From these results, we propose that the Ha alignment effect in
this object is produced by biconical gas clouds, which are swept up by the
passage of radio jets, and are ionized by strong UV radiation from a hidden
AGN. The continuum image consists of two components, a stellar-like point
source and an extended diffuse galaxy. These are supposed to be a type-2 AGN
and its host galaxy. The SED is fitted by a combination of spectra of a
reddened dust-scattered AGN and an instantaneous starburst population of 500
Myr old. The stellar mass of the galaxy is estimated to be 3e11 M_solar, which
is as large as that of typical 3C radio galaxies at z=1.

</DOC>
<DOC>
<DOCNO> 102513 </DOCNO>
Quantum Logic in Intuitionistic Perspective


  In their seminal paper Birkhoff and von Neumann revealed the following
dilemma: "... whereas for logicians the orthocomplementation properties of
negation were the ones least able to withstand a critical analysis, the study
of mechanics points to the distributive identities as the weakest link in the
algebra of logic." In this paper we eliminate this dilemma, providing a way for
maintaining both. Via the introduction of the "missing" disjunctions in the
lattice of properties of a physical system while inheriting the meet as a
conjunction we obtain a complete Heyting algebra of propositions on physical
properties. In particular there is a bijective correspondence between property
lattices and propositional lattices equipped with a so called operational
resolution, an operation that exposes the properties on the level of the
propositions. If the property lattice goes equipped with an
orthocomplementation, then this bijective correspondence can be refined to one
with propositional lattices equipped with an operational complementation, as
such establishing the claim made above. Formally one rediscovers via physical
and logical considerations as such respectively a specification and a
refinement of the purely mathematical result by Bruns and Lakser (1970) on
injective hulls of meet-semilattices. From our representation we can derive a
truly intuitionistic functional implication on property lattices, as such
confronting claims made in previous writings on the matter. We also make a
detailed analysis of disjunctivity vs. distributivity and finitary vs.
infinitary conjunctivity, we briefly review the Bruns-Lakser construction and
indicate some questions which are left open.

</DOC>
<DOC>
<DOCNO> 151061 </DOCNO>
A Remark on BRST Singlets


  Negative norm Hilbert space state vectors can be BRST invariant, we show in a
simplified Y-M model that such states can be created by starting with gluons
only.

</DOC>
<DOC>
<DOCNO> 119577 </DOCNO>
Discovery of a Young Radio Pulsar in a Relativistic Binary Orbit


  We report on the discovery of PSR J1141-6545, a radio pulsar in an eccentric,
relativistic 5-hr binary orbit. The pulsar shows no evidence for being
recycled, having pulse period P = 394 ms, characteristic age tau_c = 1.4 x 10^6
yr, and inferred surface magnetic dipole field strength B = 1.3 x 10^12 G. From
the mass function and measured rate of periastron advance, we determine the
total mass in the system to be (2.300 +/- 0.012) solar masses, assuming that
the periastron advance is purely relativistic. Under the same assumption, we
constrain the pulsar's mass to be M_p < 1.348 solar masses and the companion's
mass to be M_c > 0.968 solar masses (both 99% confidence). Given the total
system mass and the distribution of measured neutron star masses, the companion
is probably a massive white dwarf which formed prior to the birth of the
pulsar. Optical observations can test this hypothesis.

</DOC>
<DOC>
<DOCNO> 71360 </DOCNO>
Neutrino texture dominated by Majorana lefthanded mass matrix


  A form of mixing matrix for three active and three sterile, conventional
Majorana neutrinos is proposed. Its Majorana lefthanded part arises from the
popular bimaximal mixing matrix for three active neutrinos that works
satisfactorily in solar and atmospheric experiments if the LSND effect is
ignored. One of three sterile neutrinos, effective in the Majorana righthanded
and Dirac parts of the proposed mixing matrix, is responsible for the possible
LSND effect by inducing one of three extra neutrino mass states to exist
actively. The corresponding form of neutrino mass matrix is derived. Also, the
respective neutrino oscillation probabilities are calculated.

</DOC>
<DOC>
<DOCNO> 40663 </DOCNO>
Anti-B-B Mixing Constrains Topcolor-Assisted Technicolor


  We argue that extended technicolor augmented with topcolor requires that all
mixing between the third and the first two quark generations resides in the
mixing matrix of left-handed down quarks. Then, the anti-B_d--B_d mixing that
occurs in topcolor models constrains the coloron and Z' boson masses to be
greater than about 5 TeV. This implies fine tuning of the topcolor couplings to
better than 1%.

</DOC>
<DOC>
<DOCNO> 117490 </DOCNO>
Formation of Primordial Galaxies under UV background Radiation


  The pancake collapse of pregalactic clouds under UV background radiation is
explored with a one-dimensional sheet model. Here, attention is concentrated on
elucidating the basic physics on the thermal evolution of pregalactic clouds
exposed to diffuse UV radiation. So, we treat accurately the radiation transfer
for the ionizing photons, with solving chemical reactions regarding hydrogen
molecules as well as atoms. The self-shielding against UV radiation by H$_2$
Lyman-Werner bands, which regulates the photo-dissociation of hydrogen
molecules, is also taken into account. As a result, it is found that when the
UV background radiation is at a level of $10^{-22} (\nu/\nu_L)^{-1} {\rm erg~
s^{-1} cm^{-2} Hz^{-1} str^{-1}}$, the cloud evolution bifurcates with a
critical mass as $M_{\rm SB} = 2.2\times 10^{11} M_\odot [(1+z_c)/5]^{-4.2}$,
where $z_c$ is the final collapse epoch. A cloud more massive than $M_{\rm SB}$
cools below $5\times 10^3$K due to H$_2$ line emission at the pancake collapse
and would undergo the initial starburst. The pancake possibly evolves into a
virialized system in a dissipationless fashion. Consequently, this leads to the
dissipationless galaxy formation at $3\lsim z_c \lsim 10$. A cloud less massive
than $M_{\rm SB}$ cannot cool by H$_2$ emission shortly after the pancake
collapse, but could cool in the course of shrinking to the rotation barrier.
This is likely to lead to the dissipational galaxy formation at relatively low
redshifts as $0\lsim z_c \lsim 4$. The present results provide a solid physical
mechanism which controls the star formation efficiency in the pregalactic
clouds. In the context of a standard CDM cosmology, $M_{\rm SB}$ lies between
1$\sigma$ and 2$\sigma$ density fluctuations.

</DOC>
<DOC>
<DOCNO> 101806 </DOCNO>
Geometrical Interpretation of Solutions of Certain PDEs


  We proved that the solutions of $C^2$ class of certain ODEs or PDEs belong to
a class of harmonic maps between two convenient generalized Lagrange spaces.

</DOC>
<DOC>
<DOCNO> 11082 </DOCNO>
Conductivity sum rule, implication for in-plane dynamics and c-axis


  Recently observed $c$-axis optical sum rule violations indicate non-Fermi
liquid in-plane behavior. For coherent $c$-axis coupling, the observed flat,
nearly frequency independent $c$-axis conductivity $\sigma_{1}(\omega)$ implies
a large in-plane scattering rate $\Gamma$ around $(0,\pi)$ and therefore any
pseudogap that might form at low frequency in the normal state will be smeared.
On the other hand incoherent $c$-axis coupling places no restriction on the
value of $\Gamma$ and gives a more consistent picture of the observed sum rule
violation which, we find in some cases, can be less than half.

</DOC>
<DOC>
<DOCNO> 69870 </DOCNO>
Phenomenology of Pseudo Dirac Neutrinos


  We formulate general conditions on $3\times 3$ neutrino mass matrices under
which a degenerate pair of neutrinos at a high scale would split at low scale
by radiative corrections involving only the standard model fields. This
generalizes the original observations of Wolfenstein on pseudo Dirac neutrinos
to three generations. A specific model involving partially broken discrete
symmetry and solving the solar and atmospheric anomalies is proposed. The
symmetry pattern of the model naturally generates two large angles one of which
can account for the large angle MSW solution to the solar neutrino problem.

</DOC>
<DOC>
<DOCNO> 68572 </DOCNO>
Electrons and Photons: Fact not Fiction


  The particle Fock space of the matter fields in QED can be constructed using
the free creation and annihilation operators. However, these particle operators
are not, even at asymptotically large times, the modes of the matter fields
that enter the QED Lagrangian. In this letter we construct the fields which do
recover such particle modes at large times. We are thus able to demonstrate for
the first time that, contrary to statements found in the literature, a
relativistic description of charged particles in QED exists.

</DOC>
<DOC>
<DOCNO> 12550 </DOCNO>
Phase transitions, stability, and dielectric response of the domain


  We present the first analytical study of phase transitions in
ferroelastic-ferroelectric epitaxial thin films on exactly solvable model. The
emerging domain structure with domains of equal width (which may be
exponentially large on a "soft" substrate) always remains stable irrespective
of the film thickness. The dielectric response of an epitaxial film is {\em
smaller} than that of a free film, in striking contrast with assertions in the
literature.

</DOC>
<DOC>
<DOCNO> 67948 </DOCNO>
Fat Brane Phenomena


  Gravitons could permeate extra space dimensions inaccessible to all other
particles, which would be confined to ``branes''. We point out that these
branes could be ``fat'' and have a non-vanishing width in the dimensions
reserved for gravitons. In this case the other particles, confined within a
finite width, should have ``branon'' excitations. Chiral fermions behave
differently from bosons under dimensional reduction, and they may --or may
not-- be more localized than bosons. All these possibilities are in principle
testable and distinguishable, they could yield spectacular signatures at
colliders, such as the production of the first branon excitation of $\gamma$'s
or $Z$'s, decaying into their ground state plus a quasi-continuum of graviton
recurrences. We explore these ideas in the realm of a future lepton collider
and we individuate a {\it dimensiometer}: an observable that would cleanly
diagnose the number of large ``extra'' dimensions.

</DOC>
<DOC>
<DOCNO> 100260 </DOCNO>
Hurwitz numbers and intersections on moduli spaces of curves


  This article is an extended version of preprint math.AG/9902104. We find an
explicit formula for the number of topologically different ramified coverings
of a sphere by a genus g surface with only one complicated branching point in
terms of Hodge integrals over the moduli space of genus g curves with marked
points.

</DOC>
<DOC>
<DOCNO> 40416 </DOCNO>
Jet Substructure at HERA


  Measurements of jet shapes and subjet multiplicities in photoproduction
performed by ZEUS are presented and compared to leading-logarithm parton-shower
Monte Carlo models. The predicted differences on the size of gluon- and
quark-initiated jets are used to select samples to study the dynamics of the
subprocesses.

</DOC>
<DOC>
<DOCNO> 118195 </DOCNO>
Interplanetary Network Localization of GRB991208 and the Discovery of


  The extremely energetic (~10^-4 erg/cm^2) gamma-ray burst (GRB) of 1999
December 8 was triangulated to a ~14 sq. arcmin. error box ~1.8 d after its
arrival at Earth with the 3rd interplanetary network (IPN), consisting of the
Ulysses, Near Earth Asteroid Rendezvous (NEAR), and WIND spacecraft. Radio
observations with the Very Large Array ~2.7 d after the burst revealed a bright
fading counterpart whose position is consistent with that of an optical
transient source whose redshift is z=0.707. We present the time history, peak
flux, fluence, and refined 1.3 sq. arcmin. error box of this event, and discuss
its energetics. This is the first time that a counterpart has been found for a
GRB localized only by the IPN.

</DOC>
<DOC>
<DOCNO> 10519 </DOCNO>
New theory of the gamma-alpha phase transition in Ce: quadrupolar


  We present a theoretical model of the "isostructural" \gamma-\alpha phase
transition in Ce which is based on quadrupolar interactions due to coupled
charge density fluctuations of 4f electrons and of conduction electrons.
Conduction electrons are treated in tight-binding approximation. The
\gamma-\alpha transition is described as an orientational ordering of
quadrupolar electronic densities in a Pa3 structure. The quadrupolar order of
the conduction electron densities is complementary to the quadrupolar order of
4f electron densities. The inclusion of conduction electrons leads to an
increase of the lattice contraction at the \gamma-\alpha transition in
comparison to the sole effect of 4f electrons. We calculate the Bragg
scattering law and suggest synchrotron radiation experiments in order to check
the Pa3 structure. The theory is capable of accounting for transitions to
phases of non-cubic symmetry, but it is not sufficient to describe the magnetic
phenomena which we ascribe to the Kondo mechanism. We also present a
microscopic derivation of multipolar interactions and discuss the crystal field
of \gamma-Ce.

</DOC>
<DOC>
<DOCNO> 117081 </DOCNO>
Universal Tunnelling Time in photonic Barriers


  Tunnelling transit time for a frustrated total internal reflection in a
double-prism experiment was measured using microwave radiation. We have found
that the transit time is of the same order of magnitude as the corresponding
transit time measured either in an undersized waveguide (evanescent modes) or
in a photonic lattice. Moreover we have established that in all such
experiments the tunnelling transit time is approximately equal to the
reciprocal 1/f of the corresponding frequency of radiation.

</DOC>
<DOC>
<DOCNO> 170815 </DOCNO>
Quantum Database Search can do without Sorting


  Sorting is a fundamental computational process, which facilitates subsequent
searching of a database. It can be thought of as factorisation of the search
process. The location of a desired item in a sorted database can be found by
classical queries that inspect one letter of the label at a time. For an
unsorted database, no such classical quick search algorithm is available. If
the database permits quantum queries, however, then mere digitisation is
sufficient for efficient search. Sorting becomes redundant with the quantum
superposition of states. A quantum algorithm is written down which locates the
desired item in an unsorted database a factor of two faster than the best
classical algorithm can in a sorted database. This algorithm has close
resemblance to the assembly process in DNA replication.

</DOC>
<DOC>
<DOCNO> 11256 </DOCNO>
Noisy random resistor networks: renormalized field theory for the


  We study the multifractal moments of the current distribution in randomly
diluted resistor networks near the percolation treshold. When an external
current is applied between to terminals $x$ and $x^\prime$ of the network, the
$l$th multifractal moment scales as $M_I^{(l)} (x, x^\prime) \sim | x -
x^\prime |^{\psi_l /\nu}$, where $\nu$ is the correlation length exponent of
the isotropic percolation universality class. By applying our concept of master
operators [Europhys. Lett. {\bf 51}, 539 (2000)] we calculate the family of
multifractal exponents $\{\psi_l \}$ for $l \geq 0$ to two-loop order. We find
that our result is in good agreement with numerical data for three dimensions.

</DOC>
<DOC>
<DOCNO> 169959 </DOCNO>
Manipulating motional states by selective vibronic interaction in two


  We present a selective vibronic interaction for manipulating motional states
in two trapped ions, acting resonantly on a previously chosen vibronic subspace
and dispersively on all others. This is done respecting technical limitations
on ionic laser individual addressing. We discuss the generation of Fock states
and entanglement in the ionic collective motional degrees of freedom, among
other applications.

</DOC>
<DOC>
<DOCNO> 85532 </DOCNO>
2+1 gravity, chaos and time machines


  2+1 gravity for spacetimes with topology RxT^2 has been much studied. We add
a description of how to extend these spacetimes across a Cauchy horizon into a
region where the torus becomes Lorentzian. The result is a one parameter family
of tori given by a geodesic in the "Teichmueller space" of Lorentzian tori. We
describe this in detail. We also point out that if the modular group is
regarded as part of the gauge group then these spacetimes offer a nice toy
model for the dynamics of Bianchi IX models; in the region where the tori are
spacelike the dynamics is described exactly by a hyperbolic billiard. On the
other hand the modular group acts ergodically on the Teichmueller space of
Lorentzian tori.

</DOC>
<DOC>
<DOCNO> 71819 </DOCNO>
Nonlinear Gluon Evolution in the Color Glass Condensate: I


  We consider a nonlinear evolution equation recently proposed to describe the
small-$x$ hadronic physics in the regime of very high gluon density. This is a
functional Fokker-Planck equation in terms of a classical random color source,
which represents the color charge density of the partons with large $x$. In the
saturation regime of interest, the coefficients of this equation must be known
to all orders in the source strength. In this first paper of a series of two,
we carefully derive the evolution equation, via a matching between classical
and quantum correlations, and set up the framework for the exact background
source calculation of its coefficients. We address and clarify many of the
subtleties and ambiguities which have plagued past attempts at an explicit
construction of this equation. We also introduce the physical interpretation of
the saturation regime at small $x$ as a Color Glass Condensate. In the second
paper we shall evaluate the expressions derived here, and compare them to known
results in various limits.

</DOC>
<DOC>
<DOCNO> 11681 </DOCNO>
Self-consistent solutions of Ginzburg-Landau equations and


  Self-consistent solutions of the Ginzburg-Landau system of equations, which
describe the order parameter and the magnetic field distribution in a long
superconducting cylinder of finite radius R, in external magnetic field H, when
vortex line, carrying m flux quanta, is situated on the cylinder axis (a giant
m-vortex state), are studied numerically. If the field H exceeds some critical
value H_s, the giant m-vortex solution becomes unstable and passes to a new
stable edge-suppressed form. The quantum number m in this state does not
change, but the order parameter diminishes by a jump (almost to zero) near the
cylinder surface; however, superconductivity remains in the deep, at some
distance from a cylinder axis. This edge-suppressed state exist in the fields
H_s<H<H_c, where H_c is the field, in which the second order phase transition
into the normal state occures. (In the case of large radii R and finite m the
field H_c coincides with critical field H_{c2}, in which superconductivity
vanishes in the bulk.) If the vorticity m is large, the edge-suppressed state
degenerates into the usual state of surface superconductivity, and may survive
up to the field H_{c3}=1.69H_{c2}. The magnetic moment, total magnetic flux,
the Gibbs free energies are found, as functions of the field H, for different
radii R, vorticities m and parameters \kappa of GL-theory. The intervals of R,
\kappa, m are found, where the edge-suppressed solutions exist. The giant
m-vortex states exist in both type-I and type-II superconductors, but the
edge-suppressed solutions are possible only in type-II superconductors (with
\kappa > 1/sqrt{2}). The paramagnetic effect in mesoscopic samples and also the
possible connection of the theory and experiment are shortly discussed.

</DOC>
<DOC>
<DOCNO> 122931 </DOCNO>
The Stanford Cluster Search for Distant Galaxy Clusters


  We describe the scientific motivation behind, and the methodology of, the
Stanford Cluster Search (StaCS), a program to compile a catalog of optically
selected clusters of galaxies at intermediate and high (0.3 < z < 1) redshifts.
The clusters are identified using an matched filter algorithm applied to deep
CCD images covering approximately 60 square degrees of sky. These images are
obtained from several data archives, principally that of the Berkeley Supernova
Cosmology Project of Perlmutter et al. Potential clusters are confirmed with
spectroscopic observations at the 9.2 m Hobby-Eberly Telescope. Follow-up
observations at optical, sub-mm, and X-ray wavelengths are planned in order to
estimate cluster masses. Our long-term scientific goal is to measure the
cluster number density as a function of mass and redshift, which is sensitive
to the cosmological density parameter, and the amplitude of density
fluctuations on cluster scales. Our short-term goals are the detection of
high-redshift cluster candidates over a broad mass range and the measurement of
evolution in cluster scaling relations. The combined data set will contain
clusters ranging over an order of magnitude in mass, and allow constraints on
these parameters accurate to ~10%. We present our first spectroscopically
confirmed cluster candidates and describe how to access them electronically.

</DOC>
<DOC>
<DOCNO> 12030 </DOCNO>
Quasiboson representations of sl(n+1) and generalized quantum statistics


  Generalized quantum statistics will be presented in the context of
representation theory of Lie (super)algebras. This approach provides a natural
mathematical framework, as is illustrated by the relation between para-Bose and
para-Fermi operators and Lie (super)algebras of type B. Inspired by this
relation, A-statistics is introduced, arising from representation theory of the
Lie algebra A_n. The Fock representations for A_n=sl(n+1) provide microscopic
descriptions of particular kinds of exclusion statistics, which may be called
quasi-Bose statistics. It is indicated that A-statistics appears to be the
natural statistics for certain lattice models in condensed matter physics.

</DOC>
<DOC>
<DOCNO> 101769 </DOCNO>
The top Chern class of the Hodge bundle on the moduli space of abelian


  We give upper and lower bounds for the order of the top Chern class of the
Hodge bundle on the moduli space of principally polarized abelian varieties. We
also give a generalization to higher genera of the famous formula $12
\lambda_1=\delta$ for genus 1.

</DOC>
<DOC>
<DOCNO> 12362 </DOCNO>
Critical behaviour of the two-dimensional Ising susceptibility


  We report computations of the short-distance and the long-distance (scaling)
contributions to the square-lattice Ising susceptibility in zero field close to
T_c. Both computations rely on the use of nonlinear partial difference
equations for the correlation functions. By summing the correlation functions,
we give an algorithm of complexity O(N^6) for the determination of the first N
series coefficients. Consequently, we have generated and analysed series of
length several hundred terms, generated in about 100 hours on an obsolete
workstation. In terms of a temperature variable, \tau, linear in T/T_c-1, the
short-distance terms are shown to have the form \tau^p(ln|\tau|)^q with p>=q^2.
To O(\tau^14) the long-distance part divided by the leading \tau^{-7/4}
singularity contains only integer powers of \tau. The presence of irrelevant
variables in the scaling function is clearly evident, with contributions of
distinct character at leading orders |\tau|^{9/4} and |\tau|^{17/4} being
identified.

</DOC>
<DOC>
<DOCNO> 116978 </DOCNO>
Determining Phase-Space Properties of the LEDA RFQ Output Beam


  Quadrupole scans were used to characterize the LEDA RFQ beam. Experimental
data were fit to computer simulation models for the rms beam size. The codes
were found to be inadequate in accurately reproducing details of the wire
scanner data. When this discrepancy is resolved, we plan to fit using all the
data in wire scanner profiles, not just the rms values, using a 3-D nonlinear
code.

</DOC>
<DOC>
<DOCNO> 100597 </DOCNO>
On the generation of linear groups by combinatoric groups


  It is described the group of arrowy permutations (that is extension of
symmetric group) and the consequent process of generation of GL(n) and some its
subgroups by this combinatoric group and its subgroups.

</DOC>
<DOC>
<DOCNO> 119508 </DOCNO>
Optical, UV, and X-ray Clues to the Nature of Narrow Line AGNs


  AGNs with narrow Balmer lines show various extreme properties. In particular,
rapid X-ray variability, steep X-ray spectra, peculiar optical and UV line
ratios, and possibly peculiar line profiles. Since all these phenomena occur
together they are likely to be related to one specific underlying physical
parameter. I review recent evidence, based on HST imaging of low z quasars,
which suggests that the H-beta line width and continuum luminosity of quasars
provide a reasonably accurate estimate of the black hole mass. This implies
that narrow-line AGN have relatively low black hole masses, and thus high
L/L_Edd, as independently suggested based on their steep X-ray spectra. I
present additional evidence suggesting that the X-ray variability and the radio
loudness are primarily driven by the black hole mass. The high mass inflow rate
into the core of narrow-line AGNs may produce a denser and more enriched BLR, a
high column radiation pressure driven outflow, and a smaller illumination angle
for the NLR, as suggested by the observed emission line properties. Narrow-line
AGNs may thus provide important clues for understanding the rich overall
phenomenology of AGNs.

</DOC>
<DOC>
<DOCNO> 170701 </DOCNO>
 A Unified Treatment for XXX-Heisenberg Model and Haldane-Shastry Model


  A unified treatment is developed for the XXX-Heisenberg model and a
long-ranged interaction model (the $H_2$ in Haldane-Shastry model) from the
point of view of shift operators (or raising and lowering operators), based on
which the energy spectra of the spin-chain models are determined. Some physical
discussions are also made.

</DOC>
<DOC>
<DOCNO> 152106 </DOCNO>
Towards a supersymmetric non-abelian Born-Infeld theory


  We define an iterative procedure to obtain a non-abelian generalization of
the Born-Infeld action. This construction is made possible by the use of the
severe restrictions imposed by kappa-symmetry. We have calculated all bosonic
terms in the action up to terms quartic in the Yang-Mills field strength and
all fermion bilinear terms up to terms cubic in the field strength. Already at
this order the fermionic terms do not satisfy the symmetric trace-prescription.

</DOC>
<DOC>
<DOCNO> 119865 </DOCNO>
Wide Field Imaging. I. Applications of Neural Networks to object


  [Abriged] Astronomical Wide Field Imaging performed with new large format CCD
detectors poses data reduction problems of unprecedented scale which are
difficult to deal with traditional interactive tools. We present here NExt
(Neural Extractor): a new Neural Network (NN) based package capable to detect
objects and to perform both deblending and star/galaxy classification in an
automatic way. Traditionally, in astronomical images, objects are first
discriminated from the noisy background by searching for sets of connected
pixels having brightnesses above a given threshold and then they are classified
as stars or as galaxies through diagnostic diagrams having variables choosen
accordingly to the astronomer's taste and experience. In the extraction step,
assuming that images are well sampled, NExt requires only the simplest a priori
definition of "what an object is" (id est, it keeps all structures composed by
more than one pixels) and performs the detection via an unsupervised NN
approaching detection as a clustering problem which has been thoroughly studied
in the artificial intelligence literature. In order to obtain an objective and
reliable classification, instead of using an arbitrarily defined set of
features, we use a NN to select the most significant features among the large
number of measured ones, and then we use their selected features to perform the
classification task. In order to optimise the performances of the system we
implemented and tested several different models of NN. The comparison of the
NExt performances with those of the best detection and classification package
known to the authors (SExtractor) shows that NExt is at least as effective as
the best traditional packages.

</DOC>
<DOC>
<DOCNO> 119755 </DOCNO>
Constrains on parameters of magnetic field decay for accreting isolated


  The influence of exponential magnetic field decay (MFD) on the spin evolution
of isolated neutron stars is studied. The ROSAT observations of several X-ray
sources, which can be accreting old isolated neutron stars, are used to
constrain the exponential and power-law decay parameters. We show that for the
exponential decay the ranges of minimum value of magnetic moment, $\mu_b$, and
the characteristic decay time, $t_d$, $\sim 10^{29.5}\ge \mu_b \ge 10^{28} 
{\rm G} {\rm cm}^3$, $\sim 10^8\ge t_d \ge 10^7 {\rm yrs}$ are excluded
assuming the standard initial magnetic moment, $\mu_0=10^{30} {\rm G} {\rm
cm}^3$. For these parameters, neutron stars would never reach the stage of
accretion from the interstellar medium even for a low space velocity of the
stars and a high density of the ambient plasma. The range of excluded
parameters increases for lower values of $\mu_0$.
  We also show, that, contrary to exponential MFD, no significant restrictions
can be made for the parameters of power-law decay from the statistics of
isolated neutron star candidates in ROSAT observations.
  Isolated neutron stars with constant magnetic fields and initial values of
them less than $\mu_0 \sim 10^{29} {\rm G} {\rm cm}^3$ never come to the stage
of accretion.
  We briefly discuss the fate of old magnetars with and without MFD, and
describe parameters of old accreting magnetars.

</DOC>
<DOC>
<DOCNO> 120074 </DOCNO>
Sloshing in High Speed Galaxy Interactions


  Observations of lopsided spiral galaxies motivated us to explore whether the
rapid passage of a companion galaxy could cause them. We examine whether the
center of mass of the visible matter becomes displaced from the center of mass
of the dark halo during the intruder's passage, thereby causing an asymmetric
response and asymmetric structure. Two dimensional $N$-body simulations
indicate that this can happen.
  We also explore some consequences of this offset. These include the center of
mass of the visible disk following a decaying orbit around the halo center of
mass and the development of transient one-armed spirals that persist for up to
six rotation periods.
  We then study the results of a variety of initial conditions based on such
offsets. We report on the results of several runs in which we initially offset
a disk from its halo's center of mass by an amount typical of the above
interaction. In some runs the halo is free to move, while in others it is held
fixed. We used three different mass distributions for the halo in these runs.
We find that the disk's center of mass spiraled inward creating a variety of
observed or observable phenomena including one-armed spirals, massive clumps of
particles, and counter-rotating waves. The systems settle into relatively
axisymmetric configurations. Whether or not the end states included a bar
depended on a variety of initial conditions.

</DOC>
<DOC>
<DOCNO> 120844 </DOCNO>
Hot dust in two hard Chandra X-ray sources


  The two brightest hard X-ray sources discovered serendipitously by Chandra in
the field of the lensing cluster A2390 are found to have ISOCAM counterparts at
6.7 and 15 micron. We use this fact, together with their non-detection by SCUBA
at 850 micron, as the basis for DUSTY radiative transfer modelling of their
infrared spectral energy distributions. For the best-fitting models, we find
that the dust which reprocesses the optical--UV light in these Compton-thin AGN
is heated to near its sublimation temperature (above 1000K), with an inner
radius within a parsec of the nucleus. Some warm dust models with inner
temperatures of 200K are also formally acceptable. These findings strongly
support the obscured AGN hypothesis for the new hard X-ray Chandra sources,
which lack both strong emission lines and 850 micron SCUBA detections.

</DOC>
<DOC>
<DOCNO> 39715 </DOCNO>
SNO: Predictions for Ten Measurable Quantities


  We calculate the range of predicted values for 10 quantities that will be
measured by the Sudbury Neutrino Observatory (SNO). We use neutrino oscillation
solutions (vacuum and MSW; active and sterile neutrinos) that are globally
consistent with all available neutrino data and estimate realistic theoretical
and experimental uncertainties. The neutral current to charged current double
ratio is predicted to be more than 9 sigma from the no-oscillation solution for
all of the currently favored neutrino oscillation solutions. The best-fit
oscillation solutions predict a CC day-night rate difference between -0.1% and
+12.5% and a NC day-night difference < 0.01%. We present also the predicted
range for the first and the second moments of the charged current electron
recoil energy spectrum, the charged current, the neutral current, and the
neutrino-electron scattering rates, the seasonal dependence of the charged
current rate, and the double ratio of neutrino-electron scattering rate to
charged current rate.

</DOC>
<DOC>
<DOCNO> 68761 </DOCNO>
Two sterile neutrinos as a consequence of matter structure


  An algebraic argument based on a series of generalized Dirac equations,
truncated by an "intrinsic Pauli principle", shows that there should exist two
sterile neutrinos as well as three families of leptons and quarks. Then, the
influence of these additional neutrinos on neutrino oscillations is studied. As
an example, a specific model of effective five-neutrino texture is proposed,
where only the nearest neighbours in the sequence of five neutrinos ordered as
$\nu_s, \nu'_s, \nu_e, \nu_\mu, \nu_\tau$ are coupled through the 5x5 mass
matrix. Its diagonal elements are taken as negligible in comparison with its
nonzero off-diagonal entries.

</DOC>
<DOC>
<DOCNO> 68108 </DOCNO>
Perspectives in High-Energy Physics


  I sketch some pressing questions in several active areas of particle physics
and outline the challenges they present for the design and operation of
detectors.

</DOC>
<DOC>
<DOCNO> 118062 </DOCNO>
The properties of cooling flows in X-ray luminous clusters of galaxies


  We discuss the X-ray properties of the cooling flows in a sample of thirty
highly X-ray luminous clusters of galaxies observed with the ASCA and ROSAT
satellites. We demonstrate the need for multiphase models to consistently
explain the spectral and imaging X-ray data for the clusters. The mass
deposition rates of the cooling flows, independently determined from the ASCA
spectra and ROSAT images, exhibit good agreement and exceed 1000 solar masses
per year in the largest systems. We confirm the presence of intrinsic X-ray
absorption in the clusters using a variety of spectral models. The measured
equivalent hydrogen column densities of absorbing material are sensitive to the
spectral models used in the analysis, varying from average values of a few
10^{20} atom/cm^2 for a simple isothermal emission model, to a few 10^{21}
atom/cm^2 using our preferred cooling flow models, assuming in each case that
the absorber lies in a uniform foreground screen. The true intrinsic column
densities are likely to be even higher if the absorbing medium is distributed
throughout the clusters. We summarize the constraints on the nature of the
X-ray absorber from observations in other wavebands. A significant part of the
X-ray absorption may be due to dust.

</DOC>
<DOC>
<DOCNO> 68614 </DOCNO>
Semi-classical Description of Exclusive Meson Pair Production in


  A semi-classical picture is given for the production of exclusive meson pairs
in \gamma\gamma^* scattering using elements of the Lund string fragmentation
model, spin and C-parity conservation. The model can be generalized to the
production of any few meson states in scattering reactions at intermediate
momentum transfers. As an example we show that we get a consistent description
for the time-like pion form factor. For the reaction \gamma\gamma^*\to
\pi^+\pi^- we find a seizable cross section at LEP2 energies.

</DOC>
<DOC>
<DOCNO> 120148 </DOCNO>
The Extraordinary `Superthin' Spiral Galaxy UGC7321. II. The Vertical


  We explore the vertical light distribution as a function of galactocentric
radius in the edge-on (i=88) Sd `superthin' galaxy UGC7321. UGC7321 is a
low-luminosity spiral (M_B,i=-17.0) with a diffuse, low surface brightness
stellar disk and no discernible bulge component. Within 0.25' (725 pc) of the
disk center the global luminosity profile of UGC7321 can be reasonably
characterized by an exponential function with a scale height h_z=2.9" (140 pc)
in H and h_z=3.1" (150 pc) in R, making this among the thinnest galaxy disks
know. Near the disk center we derive a ratio of disk scale length to global
disk scale height h_r/h_z=14 in both H and R; near the edge of the disk,
h_r/h_z=10. At intermediate galactocentric radii (0.25'<r<1.5'), the disk of
UGC7321 becomes less peaked than an exponential near the galactic plane. At
these radii the vertical luminosity profiles can be well reproduced by a linear
combination of two isothermal disk components of differing scale heights. These
fits, together with the strong disk color gradients by Matthews, Gallagher, &
van Driel (1999), suggest that UGC7321 has multiple disk subcomponents
comprised of stellar populations with different ages and velocity dispersions.
Thus even examples of the thinnest pure disk galaxies exhibit complex structure
and signatures of dynamical heating.

</DOC>
<DOC>
<DOCNO> 151977 </DOCNO>
On the c-theorem in more than two dimensions


  Several pieces of evidence have been recently brought up in favour of the
c-theorem in four and higher dimensions, but a solid proof is still lacking. We
present two basic results which could be useful for this search: i) the values
of the putative c-number for free field theories in any even dimension, which
illustrate some properties of this number; ii) the general form of three-point
function of the stress tensor in four dimensions, which shows some physical
consequences of the c-number and of the other trace-anomaly numbers.

</DOC>
<DOC>
<DOCNO> 85444 </DOCNO>
Convex Functions and Spacetime Geometry


  Convexity and convex functions play an important role in theoretical physics.
To initiate a study of the possible uses of convex functions in General
Relativity, we discuss the consequences of a spacetime $(M,g_{\mu \nu})$ or an
initial data set $(\Sigma, h_{ij}, K_{ij})$ admitting a suitably defined convex
function. We show how the existence of a convex function on a spacetime places
restrictions on the properties of the spacetime geometry.

</DOC>
<DOC>
<DOCNO> 12411 </DOCNO>
Driven granular gases with gravity


  We study fluidized granular gases in a stationary state determined by the
balance between an external driving and the bulk dissipation. The two
considered situations are inspired by recent experiments, where the gravity
plays a major role as a driving mechanism: in the first case gravity acts only
in one direction and the bottom wall is vibrated, in the second case gravity
acts in both directions and no vibrating walls are present. Simulations
performed under the molecular chaos assumption show averaged profiles of
density, velocity and granular temperature which are in good agreement with the
experiments. Moreover we measure the velocity distributions which show strong
non-Gaussian behavior, as experiments pointed out, but also density
correlations accounting for clustering, at odds with the experimental results.
The hydrodynamics of the first model is discussed and an exact solution is
found for the density and granular temperature as functions of the distance
from the vibrating wall. The limitations of such a solution, in particular in a
broad layer near the wall injecting energy, are discussed.

</DOC>
<DOC>
<DOCNO> 102197 </DOCNO>
Regular components of moduli spaces of stable maps


  A component of the moduli space M_g(Y,b) of stable maps from genus g curves
to a variety Y is said to be regular if it is generically smooth and of the
expected dimension provided by deformation theory. In this note we prove
existence of regular components of M_g(Y,b) when Y is a product of projective
spaces. This result can also be seen as a general position theorem for
Brill-Noether loci in M_g.

</DOC>
<DOC>
<DOCNO> 117238 </DOCNO>
Air entrainment through free-surface cusps


  In many industrial processes, such as pouring a liquid or coating a rotating
cylinder, air bubbles are entrapped inside the liquid. We propose a novel
mechanism for this phenomenon, based on the instability of cusp singularities
that generically form on free surfaces. The air being drawn into the narrow
space inside the cusp destroys its stationary shape when the walls of the cusp
come too close. Instead, a sheet emanates from the cusp's tip, through which
air is entrained. Our analytical theory of this instability is confirmed by
experimental observation and quantitative comparison with numerical simulations
of the flow equations.

</DOC>
<DOC>
<DOCNO> 120300 </DOCNO>
The ATESP Radio Survey I. Survey Description, Observations and Data


  This paper is the first of a series reporting the results of the Australia
Telescope ESO Slice Project (ATESP) radio survey obtained at 1400 MHz with the
Australia Telescope Compact Array (ATCA) close to the South Galactic Pole (SGP)
over the region covered by the ESO Slice Project (ESP) galaxy redshift survey
(decl. ~ -40 degr). The survey consists of 16 radio mosaics with ~8"x14"
resolution and uniform sensitivity (1sigma noise level ~79 microJy) over an
area of ~26 sq.degrees. Here we present the design of the survey, we describe
the mosaic observing technique which was used to obtain an optimal combination
of uniform and high sensitivity over the whole area, and the data reduction:
the problems encountered and the solutions adopted.

</DOC>
<DOC>
<DOCNO> 117646 </DOCNO>
Shock Excitation in Interacting Galaxies: Mkn 266


  We present near infrared data on the luminous interacting system Mkn 266 (NGC
5256), comprising 2um continuum, and Br_gamma and 1-0S(1) emission line images,
together with K-band spectra. We have fitted stellar templates to the
continuum, allowing us to account for all the stellar features and hence detect
even faint gas excitation emission lines, including 8 and 11 H_2 lines in the
SW and NE nuclei respectively. Population diagrams for the excited H_2
molecules indicate that most of the 1-0S(1) in each of the nuclei has a thermal
origin. We discuss this with reference to the observed morphologies, especially
that of the 1-0S(1) line. In particular, the core of 1-0S(1) in the NE nucleus
is more compact than the 2um continuum; while in the SW nucleus the 1-0S(1) is
significantly offset by 500pc from the continuum (and other) emission. Lastly
we address the issue of the region midway between the two nuclei, where
previously a strong source of radio continuum has been observed. These results
are set in the context of interacting galaxies where shock excited emission
might be expected to occur as a direct consequence of the interaction.

</DOC>
<DOC>
<DOCNO> 12348 </DOCNO>
Electron Correlations in Partially Filled Lowest and Excited Landau


  The electron correlations near the half-filling of the lowest and excited
Landau levels (LL's) are studied using numerical diagonalization. It is shown
that in the low lying states electrons avoid pair states with relative angular
momenta ${\cal R}$ corresponding to positive anharmonicity of the interaction
pseudopotential $V({\cal R})$. In the lowest LL, the super-harmonic behavior of
$V({\cal R})$ causes Laughlin correlations (avoiding pairs with ${\cal R}=1$)
and the Laughlin-Jain series of incompressible ground states. In the first
excited LL, $V({\cal R})$ is harmonic at short range and a different series of
incompressible states results. Similar correlations occur in the paired
Moore-Read $\nu={5\over2}$ state and in the $\nu={7\over3}$ and ${8\over3}$
states, all having small total parentage from ${\cal R}=1$ and 3 and large
parentage from ${\cal R}=5$. The $\nu={7\over3}$ and ${8\over3}$ states are
different from Laughlin $\nu={1\over3}$ and ${2\over3}$ states and, in finite
systems, occur at a different LL degeneracy (flux). The series of Laughlin
correlated states of electron pairs at $\nu=2+2/(q_2+2)={8\over3}$,
${5\over2}$, ${12\over5}$, and ${7\over3}$ is proposed, although only in the
$\nu={5\over2}$ state pairing has been confirmed numerically. In the second
excited LL, $V({\cal R})$ is sub-harmonic at short range and (near the
half-filling) the electrons group into spatially separated larger $\nu=1$
droplets to minimize the number of strongly repulsive pair states at ${\cal
R}=3$ and 5.

</DOC>
<DOC>
<DOCNO> 9809 </DOCNO>
Orbitally Degenerate Spin-1 Model for Insulating V2O3


  Motivated by recent neutron, X-ray absorption and resonant scattering
experiments, we revisit the electronic structure of V2O3. We propose a model in
which S=1 V3+ ions are coupled in the vertical V-V pairs forming two-fold
orbitally degenerate configurations with S=2. Ferro-orbital ordering of the V-V
pairs gives a description which is consistent with all experiments in the
antiferromagnetic insulating phase.

</DOC>
<DOC>
<DOCNO> 11490 </DOCNO>
Origin of Magnetoresistance Anomalies in Antiferromagnetic


  Specific d-wave angular dependence of the in-plane magnetoresistence in
antiferromagnetic tetragonal $YBa_2Cu_3O_{6+x}$ ($x \sim 0.3$) on orientation
of the external magnetic field in ($a,b$) plane is assigned to the effective
hole transport through low lying excited purely oxygen doublet $O2pe_u$ state,
not the ground $b_{1g}(d_{x^2 -y^2})$ state. External magnetic field determines
the orientation of the strong exchange field for the spin-triplet
$b_{1g}e_u:{}^{3}E_u$ state of the hole $CuO_4$ center and due to the
spin-orbital coupling results in either orbital polarization of the $E_u$
doublet giving rise to the spatial anisotropy of the hole transport.
Experimental data allow to estimate parameter of the effective spin
Hamiltonian.

</DOC>
<DOC>
<DOCNO> 12100 </DOCNO>
The Symmetries of Fermion Fluids at Low Dimensions


  We point out that the quasiparticle spectrum of the Landau Fermi liquid
theory has an extra $Z_2$ symmetry, local in momentum space, which is not
generic to the Hamiltonian with interactions. Thus the Fermi liquid is in this
sense a (quantum) zero-temperature critical point.

</DOC>
<DOC>
<DOCNO> 151149 </DOCNO>
(Non)-singular brane-world cosmology induced by quantum effects in d5


  5d dilatonic gravity (bosonic sector of gauged supergravity) with non-trivial
bulk potential and with surface terms (boundary cosmological constant and trace
anomaly induced effective action for brane quantum matter) is considered. For
constant bulk potential and maximally SUSY Yang-Mills theory (CFT living on the
brane) the inflationary brane-world is constructed. The bulk is singular
asymptotically AdS space with non-constant dilaton and dilatonic de Sitter or
hyperbolic brane is induced by quantum matter effects. At the same time,
dilaton on the brane is determined dynamically. This all is natural realization
of warped compactification in AdS/CFT correspondence. For fine-tuned toy
example of non-constant bulk potential we found the non-singular dilatonic
brane-world where bulk again represents asymptotically AdS space and de Sitter
brane (inflationary phase of observable Universe) is induced exclusively by
quantum effects. The radius of the brane and dilaton are determined
dynamically. The analytically solvable example of exponential bulk potential
leading to singular asymptotically AdS dilatonic bulk space with de Sitter (or
hyperbolic) brane is also presented.In all cases under discussion the gravity
on the brane is trapped via Randall-Sundrum scenario. It is shown that
qualitatively the same types of brane-worlds occur when quantum brane matter is
described by $N$ dilaton coupled spinors.

</DOC>
<DOC>
<DOCNO> 10008 </DOCNO>
Upper critical field for anisotropic superconductivity. A tight-binding


  We study the problem of the upper critical field ($H_{c2}$) for tight-binding
electrons in a two-dimensional lattice. The external magnetic field is
introduced into the model Hamiltonian both via the Peierls substitution and the
Zeeman term. Carrying out calculations for finite systems we analyze the
influence of the external field in the commensurable and incommensurable case
on an equal footing. The upper critical field has been discussed for intrasite
as well as anisotropic intersite pairing that, in the absence of magnetic
field, has a $d_{x^2-y^2}$ symmetry. A comparison of $H_{c2}$ determined for
different symmetries shows that the on-site pairing is more affected by the
external field i.e., the critical temperature for the on-site pairing decreases
with the increase of the magnetic field faster than in the anisotropic case.
Moreover, we have shown that the tight-binding form of the Bloch energy can
lead to the upward curvature of $H_{c2}$, provided that the Fermi level is
close enough to the van Hove singularity.

</DOC>
<DOC>
<DOCNO> 101404 </DOCNO>
Polar complex numbers in n dimensions


  Polar commutative n-complex numbers of the form
u=x_0+h_1x_1+h_2x_2+...+h_{n-1}x_{n-1} are introduced in n dimensions, the
variables x_0,...,x_{n-1} being real numbers. The polar n-complex number can be
represented, in an even number of dimensions, by the modulus d, by the
amplitude \rho, by 2 polar angles \theta_+,\theta_-, by n/2-2 planar angles
\psi_{k-1}, and by n/2-1 azimuthal angles \phi_k. In an odd number of
dimensions, the polar n-complex number can be represented by d, \rho, by 1
polar angle \theta_+, by (n-3)/2 planar angles \psi_{k-1}, and by (n-1)/2
azimuthal angles \phi_k. The exponential function of a polar n-complex number
can be expanded in terms of the polar n-dimensional cosexponential functions
g_{nk}(y), k=0,1,...,n-1. Expressions are given for these cosexponential
functions. The polar n-complex numbers can be written in exponential and
trigonometric forms with the aid of the modulus, amplitude and the angular
variables. The polar n-complex functions defined by series of powers are
analytic, and the partial derivatives of the components of the polar n-complex
functions are closely related. The integrals of polar n-complex functions are
independent of path in regions where the functions are regular. The fact that
the exponential form of a polar n-complex numbers depends on the cyclic
variables \phi_k leads to the concept of pole and residue for integrals on
closed paths. The polynomials of polar n-complex variables can be written as
products of linear or quadratic factors, although the factorization may not be
unique.

</DOC>
<DOC>
<DOCNO> 84885 </DOCNO>
The Issue of Choosing Nothing: What Determines the Low Energy Vacuum


  Starting from an (unknown) quantum gravitational model, one can invoke a
sequence of approximations to progressively arrive at quantum field theory
(QFT) in curved spacetime, QFT in flat spacetime, nonrelativistic quantum
mechanics and newtonian mechanics. The more exact theory can put restrictions
on the range of possibilities allowed for the approximate theory which are not
derivable from the latter - an example being the symmetry restrictions on the
wave function for a pair of electrons. We argue that the choice of vacuum state
at low energies could be such a `relic' arising from combining the principles
of quantum theory and general relativity, and demonstrate this result in a
simple toy model. Our analysis suggests that the wave function of the universe,
when it describes the large volume limit of the universe, dynamically selects a
vacuum state for matter fields - which in turn defines the concept of particle
in the low energy limit. The result also has the potential for providing a
concrete quantum mechanical version of Mach's principle.

</DOC>
<DOC>
<DOCNO> 13245 </DOCNO>
Simulated emergence of cyclic sexual-asexual reproduction


  Motivated by the cyclic pattern of reproductive regimes observed in some
species of green flies (``{\it aphids}''), we simulate the evolution of a
population enduring harsh seasonal conditions for survival. The reproductive
regime of each female is also seasonal in principle and genetically acquired,
and can mutate for each newborn with some small probability. The results show a
sharp transition at a critical value of the survival probability in the winter,
between a reproductive regime in the fall that is predominantly sexual, for low
values of this probability, or asexual, for high values.

</DOC>
<DOC>
<DOCNO> 100531 </DOCNO>
On one class of unipotent subgroups of semisimple algebraic groups


  This paper contains a complete proof of a fundamental theorem on the
normalizers of unipotent subgroups in semisimple algebraic groups.

</DOC>
<DOC>
<DOCNO> 8912 </DOCNO>
Raman scattering study of anomalous charge-, spin-, and lattice-dynamics


  We report an inelastic light scattering study of the effects of
charge-ordering on the spin-, charge-, and lattice-dynamics in ${\rm
Bi}_{1-x}{\rm Ca}_{x}{\rm MnO}_3$ $(x>0.5)$. We find that charge-ordering
results in anomalous phonon behavior, such as the appearance of `activated'
modes. More significantly, however, the transition to the CO phase results in
the appearance of a quasielastic scattering response with the symmetry of the
spin chirality operator ($T_{1g}$); this scattering response is thus indicative
of magnetic or chiral spin fluctuations in the AFM charge-ordered phase.

</DOC>
<DOC>
<DOCNO> 118947 </DOCNO>
CMB Cosmological Parameter Estimation: Methods and Current Results


  The majority of present efforts to constrain cosmological parameters with
cosmic microwave background (CMB) anisotropy data employ approximate likelihood
functions, the time consuming nature of a complete analysis being a major
obstacle. We have performed a full (unapproximated) likelihood analysis on
several experiments that allows us to examine the various assumptions made in
these approximate methods and to evaluate their performance. Our results
indicate that care should be taken when using such approaches. With an improved
approximate method, we present some constraints on cosmological parameters
using the entire present CMB data set.

</DOC>
<DOC>
<DOCNO> 85049 </DOCNO>
Chaotic Inflation with Time-Variable Space Dimensions


  Assuming the space dimension is not constant but decreases during the
expansion of the Universe, we study chaotic inflation with the potential
$m^2\phi^2/2$. Our investigations are based on a model Universe with variable
space dimensions. We write down field equations in the slow-roll approximation,
and define slow-roll parameters by assuming the number of space dimensions
decreases continuously as the Universe expands. The dynamical character of the
space dimension shifts the initial and final value of the inflaton field to
larger values. We obtain an upper limit for the space dimension at the Planck
length. This result is in agreement with previous works for the effective time
variation of the Newtonian gravitational constant in a model Universe with
variable space dimensions.

</DOC>
<DOC>
<DOCNO> 83204 </DOCNO>
Connectivity Compression for Irregular Quadrilateral Meshes


  Applications that require Internet access to remote 3D datasets are often
limited by the storage costs of 3D models. Several compression methods are
available to address these limits for objects represented by triangle meshes.
Many CAD and VRML models, however, are represented as quadrilateral meshes or
mixed triangle/quadrilateral meshes, and these models may also require
compression. We present an algorithm for encoding the connectivity of such
quadrilateral meshes, and we demonstrate that by preserving and exploiting the
original quad structure, our approach achieves encodings 30 - 80% smaller than
an approach based on randomly splitting quads into triangles. We present both a
code with a proven worst-case cost of 3 bits per vertex (or 2.75 bits per
vertex for meshes without valence-two vertices) and entropy-coding results for
typical meshes ranging from 0.3 to 0.9 bits per vertex, depending on the
regularity of the mesh. Our method may be implemented by a rule for a
particular splitting of quads into triangles and by using the compression and
decompression algorithms introduced in [Rossignac99] and
[Rossignac&Szymczak99]. We also present extensions to the algorithm to compress
meshes with holes and handles and meshes containing triangles and other
polygons as well as quads.

</DOC>
<DOC>
<DOCNO> 170221 </DOCNO>
Coherent control of spin squeezing


  We report an interaction that controls spin squeezing in a collection of spin
1/2 particles. We describe how spin squeezing can be generated and maintained
in time. Our scheme can be applied to control the spin squeezing in a Bose
condensate with two internal spin states.

</DOC>
<DOC>
<DOCNO> 8955 </DOCNO>
Description of Quantum Beams Using a Stationary Incoherent Superposition


  An original entity is defined to study quantum beams of conserved particles.
The beam is described as a Stationary Incoherent Superposition of Wave packets
(SISOW). Mean values are time-independent confirming that the SISOW describes a
stationary flux of particles. The SISOW is a general entity that contains the
Hamiltonian eigenstates as a particular limit. The decomposition of the SISOW
into wave packets provides intrinsic dynamic information which is not
accessible from Hamiltonian eigenstates. The SISOW provides and adequate
framework to study mesoscopic systems

</DOC>
<DOC>
<DOCNO> 150967 </DOCNO>
N=2 Supersymmetric RG Flows and the IIB Dilaton


  We show that there is a non-trivial relationship between the dilaton of IIB
supergravity, and the coset of scalar fields in five-dimensional, gauged N=8
supergravity. This has important consequences for the running of the gauge
coupling in massive perturbations of the AdS/CFT correspondence. We conjecture
an exact analytic expression for the ten-dimensional dilaton in terms of
five-dimensional quantities, and we test this conjecture. Specifically, we
construct a family of solutions to IIB supergravity that preserve half of the
supersymmetries, and are lifts of supersymmetric flows in five-dimensional,
gauged N=8 supergravity. Via the AdS/CFT correspondence these flows correspond
to softly broken N=4, large N Yang-Mills theory on part of the Coulomb branch
of N=2 supersymmetric Yang-Mills. Our solutions involve non-trivial backgrounds
for all the tensor gauge fields as well as for the dilaton and axion.

</DOC>
<DOC>
<DOCNO> 178700 </DOCNO>
Annual Report for the Department of Energy: 1999-2000, Nuclear Theory


  This document is a summary of the physics research carried out by the Nuclear
Theory Group at the University of Washington during the last twelve-month
period, 1999-2000.

</DOC>
<DOC>
<DOCNO> 9585 </DOCNO>
Quantum-Mechanical Non-Perturbative Response of Driven Chaotic


  Consider a time-dependent Hamiltonian $H(Q,P;x(t))$ with periodic driving
$x(t)=A\sin(\Omega t)$. It is assumed that the classical dynamics is chaotic,
and that its power-spectrum extends over some frequency range
$|\omega|<\omega_{cl}$. Both classical and quantum-mechanical (QM) linear
response theory (LRT) predict a relatively large response for
$\Omega<\omega_{cl}$, and a relatively small response otherwise, independently
of the driving amplitude $A$. We define a non-perturbative regime in the
$(\Omega,A)$ space, where LRT fails, and demonstrate this failure numerically.
For $A>A_{prt}$, where $A_{prt}\propto\hbar$, the system may have a relatively
strong response for $\Omega>\omega_{cl}$, and the shape of the response
function becomes $A$ dependent.

</DOC>
<DOC>
<DOCNO> 10066 </DOCNO>
Liquid-Solid Transition of Hard Spheres Under Gravity


  We investigate the liquid-solid transition of two dimensional hard spheres in
the presence of gravity. We determine the transition temperature and the
fraction of particles in the solid regime as a function of temperature via
Even-Driven molecular dynamics simulations and compare them with the
theoretical predictions. We then examine the configurational statistics of a
vibrating bed from the view point of the liquid-solid transition by explicitly
determining the transition temperature and the effective temperature, T, of the
bed, and present a relation between T and the vibration strength.

</DOC>
<DOC>
<DOCNO> 118497 </DOCNO>
Broad-Band X-Ray Study of a Transient Pulsar RX J0059.2-7138


  We report on the results of the ASCA and ROSAT observations on RX
J0059.2-7138, a transient X-ray pulsar in the Small Magellanic Cloud. The
barycentric pulse period has been precisely determined to be 2.763221 +-
0.000004 s. The pulse shape is almost identical in all of the energy bands. The
pulse fraction increases with the photon energy below ~2 keV, while it is
nearly constant at ~37% above ~2 keV. The X-ray spectrum has been found to
consist of two components. One is dominant above 2 keV, and exhibits sinusoidal
pulsations. This component is well described by a typical model found in many
X-ray binary pulsars, a power-law of photon index 0.4 with an exponential
cut-off at 6.5 keV. The other is dominant below 1 keV and shows no significant
pulsation. This component is represented by either a broken power-law with
photon indices of 2.6 and 5.1 below and above a break energy of 0.9 keV, or a
metal-poor thin-thermal plasma with a temperature of 0.37 keV. The
phase-averaged luminosity is ~1E38 erg s^-1 (0.1-10.0 keV) for both components.
A hint of oxygen over-abundance is found in the absorbing column, possibly due
to circumstellar gas ejected from an evolved companion.

</DOC>
<DOC>
<DOCNO> 9614 </DOCNO>
Island nucleation in thin-film epitaxy: A first-principles investigation


  We describe a theoretical study of the role of adsorbate interactions in
island nucleation and growth, using Ag/Pt(111) heteroepitaxy as an example.
  From density-functional theory, we obtain the substrate-mediated Ag adatom
pair interaction and we find that, past the short range, a repulsive ring is
formed about the adatoms. The magnitude of the repulsion is comparable to the
diffusion barrier. In kinetic Monte Carlo simulations, we find that the
repulsive interactions lead to island densities over an order of magnitude
larger than those predicted by nucleation theory and thus identify a severe
limitation of its applicability.

</DOC>
<DOC>
<DOCNO> 8533 </DOCNO>
Magnetization Switching in Nanowires: Monte Carlo Study with Fast


  For the investigations of thermally activated magnetization reversal in
systems of classical magnetic moments numerical methods are desirable. We
present numerical studies which base on time quantified Monte Carlo methods
where the long-range dipole-dipole interaction is calculated with the aid of
fast Fourier transformation. As an example, we study models for ferromagnetic
nanowires comparing our numerical results for the characteristic time of the
reversal process also with numerical data from Langevin dynamics simulations
where the fast Fourier transformation method is well established. Depending on
the system geometry different reversal mechanism occur like coherent rotation,
nucleation, and curling.

</DOC>
<DOC>
<DOCNO> 9758 </DOCNO>
Atomic micromotion and geometric forces in a triaxial magnetic trap


  Non-adiabatic motion of Bose-Einstein condensates of rubidium atoms arising
from the dynamical nature of a time-orbiting-potential (TOP) trap was observed
experimentally. The orbital micromotion of the condensate in velocity space at
the frequency of the rotating bias field of the TOP was detected by a
time-of-flight method. A dependence of the equilibrium position of the atoms on
the sense of rotation of the bias field was observed. We have compared our
experimental findings with numerical simulations. The nonadiabatic following of
the atomic spin in the trap rotating magnetic field produces geometric forces
acting on the trapped atoms.

</DOC>
<DOC>
<DOCNO> 99322 </DOCNO>
Markov Transitions and the Propagation of Chaos


  The propagation of chaos is a central concept of kinetic theory that serves
to relate the equations of Boltzmann and Vlasov to the dynamics of
many-particle systems. Propagation of chaos means that molecular chaos, i.e.,
the stochastic independence of two random particles in a many-particle system,
persists in time, as the number of particles tends to infinity.
  We establish a necessary and sufficient condition for a family of general
n-particle Markov processes to propagate chaos. This condition is expressed in
terms of the Markov transition functions associated to the n-particle
processes, and it amounts to saying that chaos of random initial states
propagates if it propagates for pure initial states.
  Our proof of this result relies on the weak convergence approach to the study
of chaos due to Sznitman and Tanaka. We assume that the space in which the
particles live is homeomorphic to a complete and separable metric space so that
we may invoke Prohorov's theorem in our proof.
  We also show that, if the particles can be in only finitely many states, then
molecular chaos implies that the specific entropies in the n-particle
distributions converge to the entropy of the limiting single-particle
distribution.

</DOC>
<DOC>
<DOCNO> 83412 </DOCNO>
Finding consensus in speech recognition: word error minimization and


  We describe a new framework for distilling information from word lattices to
improve the accuracy of speech recognition and obtain a more perspicuous
representation of a set of alternative hypotheses. In the standard MAP decoding
approach the recognizer outputs the string of words corresponding to the path
with the highest posterior probability given the acoustics and a language
model. However, even given optimal models, the MAP decoder does not necessarily
minimize the commonly used performance metric, word error rate (WER). We
describe a method for explicitly minimizing WER by extracting word hypotheses
with the highest posterior probabilities from word lattices. We change the
standard problem formulation by replacing global search over a large set of
sentence hypotheses with local search over a small set of word candidates. In
addition to improving the accuracy of the recognizer, our method produces a new
representation of the set of candidate hypotheses that specifies the sequence
of word-level confusions in a compact lattice format. We study the properties
of confusion networks and examine their use for other tasks, such as lattice
compression, word spotting, confidence annotation, and reevaluation of
recognition hypotheses using higher-level knowledge sources.

</DOC>
<DOC>
<DOCNO> 122693 </DOCNO>
Black Hole Magnetospheres Around Thin Disks Driving Inward and Outward


  We construct a simple model for stationary, axisymmetric black-hole
magnetospheres, in which the poloidal magnetic field is generated by a toroidal
electric current in a thin disk with the inner edge, by solving the vacuum
Maxwell equations in Schwarzschild background. In this work, to obtain a
concise analytical form of the magnetic stream function, we use the
approximation that the inner edge is far distant from the event horizon. The
global magnetospheric structure with the closed-loop and open field lines
threading the inner and outer parts of the disk is explicitly shown, claiming
that the model is useful as a starting point to study astrophysical problems
involving inward disk-driven winds to a black hole and outward ones to
infinity. The asymptotic shape of the field lines at the event horizon becomes
nearly cylindrical, while at infinity it becomes conical. The magnetic spot in
the disk connected with the black hole through the loop field lines occupies a
very narrow region with the ring area roughly equal to the horizon area. By
taking account of the existence of a uniform (external) magnetic field, we also
obtain the model for collimated open field lines. Then, it is found that the
magnetic connection between the black hole and the disk breaks down if the
uniform field is strong enough. Considering slow rotation of the magnetosphere
and angular momentum transfer by inward winds from the disk, the final
discussion is devoted to gradual disruption of the closed loops due to radial
accretion of disk plasma toward the black hole.

</DOC>
<DOC>
<DOCNO> 80843 </DOCNO>
Lattice gauge theory: A retrospective


  I discuss some of the historical circumstances that drove us to use the
lattice as a non-perturbative regulator. This approach has had immense success,
convincingly demonstrating quark confinement and obtaining crucial properties
of the strong interactions from first principles. I wrap up with some
challenges for the future.

</DOC>
<DOC>
<DOCNO> 10614 </DOCNO>
Optical Rotatory Dispersion of $\alpha$-quartz


  It is shown that some formulae describing optical rotatory dispersion of
$\alpha$-quartz with the aid of two Drude's terms reduce to the combined
formula containing one Drude's and one Chandrasekhar's term. Comparison of
various formulae describing the experimental data of $\alpha$-quartz leads to
the conclusion that the optical activity of this crystal is due to its crystal
structure only, that means the optical activity is not of molecular origin.
Further the rotatory strengths are discussed with the regard to coupled
oscillator model and to the structure of $\alpha$-quartz.

</DOC>
<DOC>
<DOCNO> 99267 </DOCNO>
Random vicious walks and random matrices


  Lock step walker model is a one-dimensional integer lattice walker model in
discrete time. Suppose that initially there are infinitely many walkers on the
non-negative even integer sites. At each tick of time, each walker moves either
to its left or to its right with equal probability. The only constraint is that
no two walkers can occupy the same site at the same time. It is proved that in
the large time limit, a certain conditional probability of the displacement of
the leftmost walker is identical to the limiting distribution of the properly
scaled largest eigenvalue of a random GOE matrix (GOE Tracy-Widom
distribution). The proof is based on the bijection between path configurations
and semistandard Young tableaux established recently by Guttmann, Owczarek and
Viennot. Statistics of semistandard Young tableaux is analyzed using the Hankel
determinant expression for the probability from the work of Rains and the
author. The asymptotics of the Hankel determinant is obtained by applying the
Deift-Zhou steepest-descent method to the Riemann-Hilbert problem for the
related orthogonal polynomials.

</DOC>
<DOC>
<DOCNO> 68594 </DOCNO>
Improved GUT and SUSY breaking by the same field


  In a previous paper, we presented a model in which the {\em same} modulus
field breaks SUSY and a simple GUT gauge group, and which has {\em dynamical}
origins for {\em both} SUSY breaking and GUT scales. In this model, the
supergravity (SUGRA) and gauge mediated (GM) contributions to MSSM scalar and
gaugino masses are comparable - this enables a realistic spectrum to be
attained since GM contribution to the right-handed (RH) slepton (mass)^2 by
itself (i.e., neglecting SUGRA contribution to sfermion {\em and} gaugino
masses) is negative. But, in general, the SUGRA contribution to sfermion masses
(from non-renormalizable contact K\"ahler terms) leads to flavor violation. In
this paper, we use the recently proposed idea of gaugino mediated SUSY breaking
(\tilde{g}MSB) to improve the above model. With MSSM matter and SUSY breaking
fields localized on separate branes in an extra dimension of size R \sim 5
M^{-1}_{Pl} (in which gauge fields propagate), the SUGRA contribution to
sfermion masses (which violates flavor) is suppressed. As in 4 dimensions, MSSM
gauginos acquire {\em non}-universal masses from both SUGRA and GM - gaugino
masses (in particular the SUGRA contribution to gaugino masses), in turn,
generate acceptable sfermion masses through RG evolution; the phenomenology is
discussed briefly. We also point out that a) in models where SUSY is broken by
a GUT non-singlet field, there is, in general, a contribution to MSSM gaugino
(and scalar) masses from the coupling to heavy gauge multiplet which {\em
might} be {\em comparable} to the SUGRA contribution and b) models of GM
proposed earlier which also have negative RH slepton (mass)^2 can be rendered
viable using the \tilde{g}MSB idea.

</DOC>
<DOC>
<DOCNO> 116413 </DOCNO>
Axicon Gaussian Laser Beams


  We deduce the simplest form for an axicon Gaussian laser beam, i.e., one with
radial polarization of the electric field.

</DOC>
<DOC>
<DOCNO> 169785 </DOCNO>
Local and Nonlocal Properties of Werner States


  We consider a special kind of mixed states -- a {\it Werner derivative},
which is the state transformed by nonlocal unitary -- local or nonlocal --
operations from a Werner state. We show the followings. (i) The amount of
entanglement of Werner derivatives cannot exceed that of the original Werner
state. (ii) Although it is generally possible to increase the entanglement of a
single copy of a Werner derivative by LQCC, the maximal possible entanglement
cannot exceed the entanglement of the original Werner state. The extractable
entanglement of Werner derivatives is limited by the entanglement of the
original Werner state.

</DOC>
<DOC>
<DOCNO> 118630 </DOCNO>
Gamma-ray Observations of the Galactic Plane at Energies E > 500 GeV


  In 1998 and 1999 the Whipple Observatory 10 m telescope was used to search
for diffuse gamma ray emission from the Galactic Plane. No signifiant evidence
of emission was found. Assuming the TeV emission profile matches EGRET
observations above 1 GeV with a differential spectral index of 2.4, we derive
an upper limit of {$\rm {3.0\cdot10^{-8}cm^{-2}s^{-1}sr^{-1}}$} for the average
diffuse emission above {{$\rm500 GeV$}} in the galactic latitude range from
{{$\rm-2^o$ to $\rm +2^o$}} at galactic longitude {{$\rm 40^o$}}. Comparisons
with EGRET observations provide a lower limit of 2.31 for the differential
spectral index of the diffuse emission, assuming there is no break in the
spectrum between 30 GeV and 500 GeV. This constrains models for diffuse
emission with a significant inverse Compton contribution.

</DOC>
<DOC>
<DOCNO> 122902 </DOCNO>
Near-IR Spectroscopy and Population Synthesis of Super Star Clusters in


  We present H- and K-band NIRSPEC spectroscopy of super star clusters (SSCs)
in the irregular starburst galaxy NGC 1569, obtained at the Keck Observatory.
We fit these photospheric spectra to NextGen model atmospheres to obtain
effective spectral types of clusters, and find that the information in both H-
and K-band spectra is necessary to remove degeneracy in the fits. The light of
SSC B is unambiguously dominated by K0 supergiants (T_eff=4400 +- 100 K, log
g=0.5 +- 0.5). The double cluster SSC A has higher T_eff (G5) and less tightly
constrained surface gravity (log g=1.3 +- 1.3), consistent with a mixed stellar
population dominated by blue Wolf-Rayet stars and red supergiants. We predict
the time evolution of infrared spectra of SSCs using Starburst99 population
synthesis models coupled with empirical stellar spectral libraries (at solar
metallicity). The resulting model sequence allows us to assign ages of 15-18
Myr for SSC B and 18-21 Myr for SSC A.

</DOC>
<DOC>
<DOCNO> 70411 </DOCNO>
Strangeness in Lattice QCD


  The status of lattice calculations in the light hadron sector is reviewed.
Special emphasis is given to recent lattice determinations of the mass of the
strange quark. The impact of non-perturbative renormalization and control over
lattice artefacts on the attainable precision is discussed in detail.
Furthermore the influence of dynamical quark effects is assessed.

</DOC>
<DOC>
<DOCNO> 10970 </DOCNO>
Equilibrium Properties of Temporally Asymmetric Hebbian Plasticity


  A theory of temporally asymmetric Hebb (TAH) rules which depress or
potentiate synapses depending upon whether the postsynaptic cell fires before
or after the presynaptic one is presented. Using the Fokker-Planck formalism,
we show that the equilibrium synaptic distribution induced by such rules is
highly sensitive to the manner in which bounds on the allowed range of synaptic
values are imposed. In a biologically plausible multiplicative model, we find
that the synapses in asynchronous networks reach a distribution that is
invariant to the firing rates of either the pre- or post-synaptic cells. When
these cells are temporally correlated, the synaptic strength varies smoothly
with the degree and phase of synchrony between the cells.

</DOC>
<DOC>
<DOCNO> 117569 </DOCNO>
Metric Perturbations and Inflationary Phase Transitions


  We study the out of equilibrium dynamics of inflationary phase transitions
and compute the resulting spectrum of metric perturbations relevant to
observation. We show that simple single field models of inflation may produce
an adiabatic perturbation spectrum with a blue spectral tilt and that the
precise spectrum depends on initial conditions at the outset of inflation.

</DOC>
<DOC>
<DOCNO> 12073 </DOCNO>
Dynamic Phase Transition in a Time-Dependent Ginzburg-Landau Model in an


  The Ginzburg-Landau model below its critical temperature in a temporally
oscillating external field is studied both theoretically and numerically. As
the frequency or the amplitude of the external force is changed, a
nonequilibrium phase transition is observed. This transition separates
spatially uniform, symmetry-restoring oscillations from symmetry-breaking
oscillations. Near the transition a perturbation theory is developed, and a
switching phenomenon is found in the symmetry-broken phase. Our results confirm
the equivalence of the present transition to that found in Monte Carlo
simulations of kinetic Ising systems in oscillating fields, demonstrating that
the nonequilibrium phase transition in both cases belongs to the universality
class of the equilibrium Ising model in zero field. This conclusion is in
agreement with symmetry arguments [G. Grinstein, C. Jayaprakash, and Y. He,
Phys. Rev. Lett. 55, 2527 (1985)] and recent numerical results [G. Korniss,
C.J. White, P. A. Rikvold, and M. A. Novotny, Phys. Rev. E (submitted)].
Furthermore, a theoretical result for the structure function of the local
magnetization with thermal noise, based on the Ornstein-Zernike approximation,
agrees well with numerical results in one dimension.

</DOC>
<DOC>
<DOCNO> 84980 </DOCNO>
Gravitational Waves from a Compact Star in a Circular, Inspiral Orbit,


  Results are presented from high-precision computations of the orbital
evolution and emitted gravitational waves for a stellar-mass object spiraling
into a massive black hole in a slowly shrinking, circular, equatorial orbit.
The focus of these computations is inspiral near the innermost stable circular
orbit (isco)---more particularly, on orbits for which the angular velocity
Omega is 0.03 < Omega/Omega_{isco} < 1. The computations are based on the
Teukolsky-Sasaki-Nakamura formalism, and the results are tabulated in a set of
functions that are of order unity and represent relativistic corrections to
low-orbital-velocity formulas. These tables can form a foundation for future
design studies for the LISA space-based gravitational-wave mission. A first
survey of applications to LISA is presented: Signal to noise ratios S/N are
computed and graphed as functions of the time-evolving gravitational-wave
frequency for representative values of the hole's mass M and spin a and the
inspiraling object's mass \mu, with the distance to Earth chosen to be r_o = 1
Gpc. These S/N's show a very strong dependence on the black-hole spin, as well
as on M and \mu. A comparison with predicted event rates shows strong promise
for detecting these waves, but not beyond about 1Gpc if the inspiraling object
is a white dwarf or neutron star. This argues for a modest lowering of LISA's
noise floor. A brief discussion is given of the prospects for extracting
information from the observed waves

</DOC>
<DOC>
<DOCNO> 83477 </DOCNO>
Abductive reasoning with temporal information


  Texts in natural language contain a lot of temporal information, both
explicit and implicit. Verbs and temporal adjuncts carry most of the explicit
information, but for a full understanding general world knowledge and default
assumptions have to be taken into account. We will present a theory for
describing the relation between, on the one hand, verbs, their tenses and
adjuncts and, on the other, the eventualities and periods of time they
represent and their relative temporal locations, while allowing interaction
with general world knowledge.
  The theory is formulated in an extension of first order logic and is a
practical implementation of the concepts described in Van Eynde 2001 and
Schelkens et al. 2000. We will show how an abductive resolution procedure can
be used on this representation to extract temporal information from texts. The
theory presented here is an extension of that in Verdoolaege et al. 2000,
adapted to VanEynde 2001, with a simplified and extended analysis of adjuncts
and with more emphasis on how a model can be constructed.

</DOC>
<DOC>
<DOCNO> 10504 </DOCNO>
Chapman-Enskog method and synchronization of globally coupled


  The Chapman-Enskog method of kinetic theory is applied to two problems of
synchronization of globally coupled phase oscillators. First, a modified
Kuramoto model is obtained in the limit of small inertia from a more general
model which includes ``inertial'' effects. Second, a modified Chapman-Enskog
method is used to derive the amplitude equation for an O(2) Takens-Bogdanov
bifurcation corresponding to the tricritical point of the Kuramoto model with a
bimodal distribution of oscillator natural frequencies. This latter calculation
shows that the Chapman-Enskog method is a convenient alternative to normal form
calculations.

</DOC>
<DOC>
<DOCNO> 119027 </DOCNO>
On the fate of gas in ultraluminous galaxies at low and high redshift


  It is often suggested that the distant galaxies recently identified in 850
micron surveys with the SCUBA bolometer array on the JCMT Telescope are
high-redshift analogues to local ultraluminous infrared galaxies, based on
their similar spectral energy distributions and luminosities. We show that
these two populations of objects must differ in at least one fundamental way
from each other. This assertion is based on a consideration of the possible
fates of gas in the high redshift SCUBA galaxies, given the requirement that
they most evolve into some subset of the low-redshift galaxy population with a
comoving density of about 10^{-4} Mpc^{-3}. One possibility is that the SCUBA
galaxies have similar gas density profiles to local ultraluminous galaxies. If
this is the case, then they must derive almost all their power from AGNs, which
appears not to be the case for local ultraluminous galaxies, which are
predominantly star-formation powered. Another possibility is that the SCUBA
galaxies have more extended gas density profiles than local ultraluminous
galaxies. In this case they must be almost all star-formation powered, and much
of the star formation in the Universe can happen in these objects. Either way
there is a significant difference between the low- and high- redshift
populations.

</DOC>
<DOC>
<DOCNO> 13782 </DOCNO>
Spin chains and combinatorics


  In this letter we continue the investigation of finite XXZ spin chains with
periodic boundary conditions and odd number of sites, initiated in paper
\cite{S}. As it turned out, for a special value of the asymmetry parameter
$\Delta=-1/2$ the Hamiltonian of the system has an eigenvalue, which is exactly
proportional to the number of sites $E=-3N/2$. Using {\sc Mathematica} we have
found explicitly the corresponding eigenvectors for $N \le 17$. The obtained
results support the conjecture of paper \cite{S} that this special eigenvalue
corresponds to the ground state vector. We make a lot of conjectures concerning
the correlations of the model. Many remarkable relations between the wave
function components are noticed. It is turned out, for example, that the ratio
of the largest component to the least one is equal to the number of the
alternating sing matrices.

</DOC>
<DOC>
<DOCNO> 102188 </DOCNO>
Consistency of Orbifold Conformal Field Theories on K3


  We explicitly determine the locations of G orbifold conformal field theories,
G=Z_M, M=2,3,4,6, G=\hat D_n, n=4,5, or G the binary tetrahedral group \hat T,
within the moduli space M^{K3} of N=(4,4) superconformal field theories
associated to K3. This is achieved purely from the known description of the
moduli space [AM94] and the requirement of a consistent embedding of orbifold
conformal field theories within M^{K3}. We calculate the Kummer type lattices
for all these orbifold limits. Our method allows an elementary derivation of
the B-field values in direction of the exceptional divisors that arise from the
orbifold procedure [Asp95,Dou97,BI97], without recourse to D-geometry. We show
that our consistency requirement fixes these values uniquely and determine them
explicitly. The relation of our results to the classical McKay correspondence
is discussed.

</DOC>
<DOC>
<DOCNO> 121659 </DOCNO>
Cluster Surveys


  I review some of the current efforts to create unbiased samples of galaxy
clusters. Readers are referred elsewhere for general wide area sky surveys and
redshift surveys, and for Sunyaev-Zeldovich, radio, infrared and submm surveys,
some of which were not designed to search primarily for clusters. My focus will
be on optical and X-ray samples and on high redshift clusters.

</DOC>
<DOC>
<DOCNO> 122504 </DOCNO>
Type Ia Supernovae and the Value of the Hubble Constant


  The methodology involved in deriving the Hubble Constant via the calibration
of the corrected peak luminosities of Type Ia supernovae (SNe) is reviewed. We
first present a re-analysis of the Calan-Tololo (C-T) and Center for
Astrophysics (CfA) Type Ia SN surveys. Bivariate linear least squares and
quadratic boot-strapped fits in peak apparent magnitude and light curve shape
are employed to correct this heterogeneous sample of peak apparent magnitudes,
resulting in an homogeneous (and excellent) secondary distance indicator: the
so-called corrected peak luminosity. We next provide an empirical calibration
for this corrected luminosity, using Cepheid-based distances for seven nearby
spiral galaxies host to Type Ia SNe. Included in this sample is the
spectroscopically peculiar SN 1991T (in NGC 4527), whose corrected peak
luminosity is shown to be indistinguishable from that of so-called ``normal''
SNe. A robust value of the Hubble Constant is derived and shown to be
H0=73+/-2(r)+/-7(s) km/s/Mpc.

</DOC>
<DOC>
<DOCNO> 71743 </DOCNO>
Parametrization of proton-proton total cross section from 10 GeV to 100


  Present estimations of proton-proton total cross section at very high
energies are obtained from cosmic rays (>10^17 eV) by means of some
approximations and the knowledge of the measured proton-air cross section at
these energies. Besides, total cross section are measured with present day high
energy colliders up to nearly 2 TeV in the center of mass (~ 10^15 eV in the
laboratory). Here we use a phenomenological model based on the
Multiple-Diffraction approach to succesfully describe data at accelerator
energies. Then we estimate with it proton-proton total cross sections at cosmic
ray energies. On the basis of a forecasting regression analysis we determine
confident errors bands, analyzing the sensitivity of our predictions to the
employed data for extrapolation.

</DOC>
<DOC>
<DOCNO> 169980 </DOCNO>
A New Method to Derive Low-Lying N-dimensional Quantum Wave Functions by


  We present a new method to derive low-lying N-dimensional quantum wave
functions by quadrature along a single trajectory. The N-dimensional
Schroedinger equation is cast into a series of readily integrable first order
ordinary differential equations. Our approach resembles the familiar W.K.B.
approximation in one dimension, but is designed to explore the classically
forbidden region and has a much wider applicability than W.K.B.. The method
also provides a perturbation series expansion and the Green's functions of the
wave equation in N-dimension, all by quadratures along a single trajectory. A
number of examples are given for illustration, including a simple algorithm to
evaluate the Stark effect in closed form to any finite order of the electric
field.

</DOC>
<DOC>
<DOCNO> 100114 </DOCNO>
Link Invariants Associated with Gauge Equivalent Solutions of the


  In this paper we investigate the construction of state models for link
invariants using representations of the braid group obtained from various gauge
choices for a solution of the trigonometric Yang-Baxter equation. Our results
show that it is possible to obtain invariants of regular isotopy (as defined by
Kauffman) which may not be ambient isotopic. We illustrate our results with
explicit computations using solutions of the trigonometric Yang-Baxter equation
associated with the one-parameter family of minimal typical representations of
the quantum superalgebra U_q[gl(2|1)]. We have implemented Mathematica code to
evaluate the invariants for all prime knots up to 10 crossings.

</DOC>
<DOC>
<DOCNO> 119141 </DOCNO>
The sources of extended continuum emission towards Q0151+048A : The host


  We present deep imaging in the U, B and I bands obtained under excellent
seeing conditions of the double quasar Q0151+048A,B and of the Damped Ly-alpha
(DLA) absorbing galaxy at z(abs) = 1.9342 named S4.
  We analyse the data employing two separate and independent methods. First we
deconvolve the images using the MCS algorithm, secondly we decompose the images
via an object based iteration process where we fit models to objects without
any attempt to improve the resolution of the data. Our detailed analysis of the
images reveals, somewhat surprisingly, that extended objects centred on the
quasars themselves are much brighter continuum sources than the DLA galaxy.
  Due to the complexity caused by the many superimposed objects, we are unable
to certify whether or not continuum emission from the DLA galaxy is detected.
Continuum emission from the extended objects centred on the positions of the
quasars is clearly seen, and the objects are tentatively identified as the
``host galaxies'' of the quasars. The flux of those host galaxies is of order
2--6% of the quasar flux, and the light profile of the brighter of the two is
clearly best fit with a de Vaucouleurs profile. We discuss two alternative
interpretations of the origin of the extended flux: i) the early stage of a
massive elliptical galaxy in the process of forming the bulk of its stars, and
ii) quasar light scattered by dust.

</DOC>
<DOC>
<DOCNO> 12018 </DOCNO>
Kinetic roughening with anysotropic growth rules


  Inspired by the chemical etching processes, where experiments show that
growth rates depending on the local environment might play a fundamental role
in determining the properties of the etched surfaces, we study here a model for
kinetic roughening which includes explicitly an anisotropic effect in the
growth rules. Our model introduces a dependence of the growth rules on the
local environment conditions, i.e. on the local curvature of the surface.
Variables with different local curvatures of the surface, in fact, present
different quenched disorder and a parameter $p$ (which could represent
different experimental conditions) is introduced to account for different time
scales for the different classes of variables. We show that the introduction of
this {\em time scale separation} in the model leads to a cross-over effect on
the roughness properties. This effect could explain the scattering in the
experimental measurements available in the literature. The interplay between
anisotropy and the cross-over effect and the dependence of critical properties
on parameter $p$ is investigated as well as the relationship with the known
universality classes.

</DOC>
<DOC>
<DOCNO> 71287 </DOCNO>
Top Mode Standard Model with Extra Dimensions


  We critically examine a version of the top mode standard model recently cast
in extra dimensions by Arkani-Hamed, Cheng, Dobrescu, and Hall, based on the
(improved) ladder Schwinger-Dyson (SD) equation for the D-(=6,8-)-dimensional
gauge theories. We find that the bulk QCD cannot have larger coupling beyond
the non-trivial ultraviolet (UV) fixed point, the existence of which is
supported by a recent lattice analysis. The coupling strength at the fixed
point is evaluated by using the one-loop renormalization group equation. It is
then found that, in a version with only the third family (as well as the gauge
bosons) living in the D-dimensional bulk, the critical (dimensionless) coupling
for dynamical chiral symmetry breaking to occur is larger than the UV fixed
point of the bulk QCD coupling for D=6, while smaller for D=8. We further find
that the improved ladder SD equation in D dimensions has an approximate
scale-invariance due to the running of the coupling and hence has an
essential-singularity scaling of the ``conformal phase transition,'' similar to
Miransky scaling in the four-dimensional ladder SD equation with a nonrunning
coupling. This essential-singularity scaling can resolve the fine-tuning even
when the cutoff (``string scale'') is large. Such a theory has a large
anomalous dimension \gamma_m=D/2 - 1 and is expected to be free from the
flavor-changing-neutral-current problem as in walking technicolor for D=4.
Furthermore, the induced bulk Yukawa coupling becomes finite even at infinite
cutoff limit (in the formal sense), similarly to the renormalizability of the
gauged Nambu-Jona-Lasinio model. Comments are made on the use of the
``effective'' coupling, which includes finite renormalization effects, instead
of the \bar{MS} running coupling in the improved ladder SD equation.

</DOC>
<DOC>
<DOCNO> 11407 </DOCNO>
Effective Hamiltonian for striped and paired states at the half-filled


  We study a pairing mechanism for the quantum Hall system using a mean field
theory with a basis on the von Neumann lattice, on which the magnetic
translations commute. In the Hartree-Fock-Bogoliubov approximation, we solve
the gap equation for spin-polarized electrons at the half-filled Landau levels.
We obtain an effective Hamiltonian which shows a continuous transition from the
compressible striped state to the paired state. Furthermore, a crossover occurs
in the pairing phase. The energy spectrum and energy gap of the quasiparticle
in the paired state is calculated numerically at the half-filled second Landau
level.

</DOC>
<DOC>
<DOCNO> 72165 </DOCNO>
Perturbative Quantum Field Theory


  This talk introduces perturbative quantum field on a heuristic level. It is
directed at an audience familiar with elements of quantum mechanics, but not
necessarily with high energy physics. It includes a discussion of the
strategies behind experimental tests of fundamental theories, and of the field
theory interpretations of these tests

</DOC>
<DOC>
<DOCNO> 121645 </DOCNO>
CO observations toward supernova remnants with associated OH 1720 MHz


  The environs of three supernova remnants (SNR) with associated OH 1720 MHz
masers, G349.7+0.2, CTB 37A and G16.7+0.1, have been surveyed in the CO J=1-0
transition with the 12 Meter Telescope of the NRAO, using the On-The-Fly
technique. These observations have revealed a number of molecular clouds
interacting with the SNR shock fronts. Most of the OH 1720 MHz masers have been
found to lie over CO concentrations, and the maser velocities are coincident
with the CO peak velocities to an accuracy better than 2 km/s. The present data
trace the interstellar medium (ISM) structures interacting with the SNRs;
however, to probe the shocked molecular gas in which the OH 1720 MHz emission
originates, higher excitation transitions and more complex species should be
observed. In CTB 37A, where the shock velocity into the molecular cloud could
be determined, it has been found to be of C-type, in agreement with theoretical
predictions. Part of the rim of G16.7+0.1 appears to be flattened by a dense
external cloud, yet the only associated OH 1720 MHz maser lies near the
opposite region of the remnant. This behavior, also observed in IC 443 and 3C
391, seems to contradict the suggestion that OH 1720 MHz maser emission occurs
mainly for transverse shocks.

</DOC>
<DOC>
<DOCNO> 10178 </DOCNO>
Amine Functionalized Cross-Linked Hybrid Full Color Phosphors Lacking


  White light tunable phosphors are obtained from a sol-gel derived siliceous
network to which oxyethylene units are covalently grafted by means of urea or
urethane cross-linkages. The bright photoluminescence is ascribed to an unusual
convolution of distinct emissions originated in the NH groups of the urea or
urethane bridges and in the siliceous nanodomains. The lifetimes of these
emissions show a remarkable temperature dependence of approximately six orders
of magnitude between $\approx 220$ and 300 K associated with the hybrids glass
transition temperature. This set of xerogels is one of the most surprising
classes of full color emitters lacking metal activator ions.

</DOC>
<DOC>
<DOCNO> 8727 </DOCNO>
The induced charge in a Frohlich polaron: Sum rule and spatial extent


  Within the path integral formalism, we derive exact expressions for
correlation functions measuring the lattice charge induced by an electron and
associated polarization in Frohlich polaron problem. We prove that a sum rule
for the total induced charge, already obtained within approximated approaches
is indeed exact. As a consequence the total induced charge is shown rigorously
to be temperature independent. In addition we perform path integral Monte Carlo
calculations of the correlation functions and we compare with variational
results based on
 Feynman method. As the temperature increases the polaron radius decreases. On
the other hand at high temperatures the electron motion is not hindered by the
lattice. These apparently contradictory results are discussed.

</DOC>
<DOC>
<DOCNO> 120692 </DOCNO>
Electron-Ion Recombination Rate Coefficients and Photoionization Cross


  Photoionization and recombination cross sections and rate coefficients are
calculated for Li-like Fe XXIV and He-like Fe XXV using the Breit-Pauli
R-matrix (BPRM) method. A complete set of total and level-specific parameters
is obtained to enable X-ray photoionization and spectral modeling. The ab
initio calculations for the unified (e + ion) recombination rate coefficients
include both the non-resonant and the resonant recombination (radiative and
di-electronic recombination, RR and DR, respectively) for (e + Fe XXV) -> Fe
XXIV and (e + Fe XXVI) -> Fe XXV. The level specific rates are computed for all
fine structure levels up to n = 10, enabling accurate computation of
recombination-cascade matrices and effective rates for the X-ray lines. The
total recombination rate coefficients for both Fe XXIV and Fe XXV differ
considerably, by several factors, from the sum of RR and DR rates currently
used to compute ionization fractions in astrophysical models. As the
photoionization/recombination calculations are carried out using an identical
eigenfunction expansion, the cross sections for both processes are
theoretically self-consistent; the overall uncertainty is estimated to be about
10-20%. All data for Fe XXIV and Fe XXV (and also for H-like Fe XXVI, included
for completeness) are available electronically.

</DOC>
<DOC>
<DOCNO> 151338 </DOCNO>
Path Integrals on Riemannian Manifolds with Symmetry and Induced Gauge


  We formulate path integrals on any Riemannian manifold which admits the
action of a compact Lie group by isometric transformations. We consider a path
integral on a Riemannian manifold M on which a Lie group G acts isometrically.
Then we show that the path integral on M is reduced to a family of path
integrals on a quotient space Q=M/G and that the reduced path integrals are
completely classified by irreducible unitary representations of G. It is not
necessary to assume that the action of G on M is either free or transitive.
Hence our formulation is applicable to a wide class of manifolds, which
includes inhomogeneous spaces, and it covers all the inequivalent
quantizations. To describe the path integral on inhomogeneous space,
stratification geometry, which is a generalization of the concept of principal
fiber bundle, is necessarily introduced. Using it we show that the path
integral is expressed as a product of three factors; the rotational energy
amplitude, the vibrational energy amplitude, and the holonomy factor. When a
singular point arises in $ Q $, we determine the boundary condition of the path
integral kernel for a path which runs through the singularity.

</DOC>
<DOC>
<DOCNO> 13075 </DOCNO>
Cavity assisted quasiparticle damping in a Bose-Einstein condensate


  We consider an atomic Bose-Einstein condensate held within an optical cavity
and interacting with laser fields. We show how the interaction of the cavity
mode with the condensate can cause energy due to excitations to be coupled to a
lossy cavity mode, which then decays, thus damping the condensate, how to
choose parameters for damping specific excitations, and how to target a range
of different excitations to potentially produce extremely cold condensates.

</DOC>
<DOC>
<DOCNO> 178842 </DOCNO>
Unfactorized versus factorized calculations for ^2H(e,e'p) reactions at


  In the literature, one often finds calculations of (e,e'p) reactions at GeV
energies using the factorization approach. Factorization implies that the
differential cross section can be written as the product of an off-shell
electron-proton cross section and a distorted missing momentum distribution.
While this factorization appears in the non-relativistic plane wave impulse
approximation, it is broken in a more realistic approach. The main source of
factorization breaking are final state interactions. In this paper, sources of
factorization breaking are identified and their numerical relevance is examined
in the reaction ^2H(e,e'p) for various kinematic settings in the GeV regime.
The results imply that factorization should not be used for precision
calculations, especially as unfactorized calculations are available.

</DOC>
<DOC>
<DOCNO> 83421 </DOCNO>
Towards Understanding the Predictability of Stock Markets from the


  This paper initiates a study into the century-old issue of market
predictability from the perspective of computational complexity. We develop a
simple agent-based model for a stock market where the agents are traders
equipped with simple trading strategies, and their trades together determine
the stock prices. Computer simulations show that a basic case of this model is
already capable of generating price graphs which are visually similar to the
recent price movements of high tech stocks. In the general model, we prove that
if there are a large number of traders but they employ a relatively small
number of strategies, then there is a polynomial-time algorithm for predicting
future price movements with high accuracy. On the other hand, if the number of
strategies is large, market prediction becomes complete in two new
computational complexity classes CPP and BCPP, which are between P^NP[O(log n)]
and PP. These computational completeness results open up a novel possibility
that the price graph of an actual stock could be sufficiently deterministic for
various prediction goals but appear random to all polynomial-time prediction
algorithms.

</DOC>
<DOC>
<DOCNO> 72050 </DOCNO>
Fourth generation effects in the $B_s \to \nu \bar{\nu} \gamma$ decay


  If the fourth generation fermions exist, the new quarks could influence the
branching ratio of the decay $B_s \to \nu \bar{\nu} \gamma$. We obtain two
solutions of the fourth generation CKM factor $V^*_{t's} V_{t'b}$ from the
decay of $B \to X_s \gamma$. With these two solutions we calculate the new
contributions of the fourth generation quark to Wilson coefficients of the
decay $B_s \to \nu \bar{\nu} \gamma$. The branching ratio of the decay $B_s \to
\nu \bar{\nu} \gamma$ in the two cases are calculated. In one case, our results
are quite different from that of SM, but almost same in another case. If a
fourth generation should exist in nature and nature chooses the former case,
this B meson decay could provide a possible test of the fourth generation
existence.

</DOC>
<DOC>
<DOCNO> 150966 </DOCNO>
Boundary Conditions, Supersymmetry and A-field Coupling for an Open


  We discuss the non-linear sigma model representing a NSR open string in a
curved background with non-zero $B_{\mu\nu}$-field. With this coupling the
theory is not automatically supersymmetric, due to boundary contributions. When
B=0 supersymmetry is ensured by the conditions that follow as the boundary
contribution to the field equations. We show that inclusion of a particular
boundary term restores this state of affairs also in the presence of a
$B$-field. The boundary conditions derived from the field equations in this
case agree with those that have been proposed for constant $B$-field. A
coupling to a boundary $A_\mu$-field will modify both the boundary conditions
and affect the supersymmetry. It is shown that there is an $A$-coupling with
non-standard fermionic part that respects both the supersymmetry and the shift
symmetry (in the $B$ and $A$ fields), modulo the (modified) boundary
conditions.

</DOC>
<DOC>
<DOCNO> 70335 </DOCNO>
Sfermion Pair Production in Polarized and Unpolarized $\gamma\gamma$


  We calculate total and differential cross sections for the production of
sfermion pairs in photon-photon collisions, including contributions from
resolved photons and arbitrary photon polarization. Sfermion production in
photon collisions depends only on the sfermion mass and charge. It is thus
independent of the details of the SUSY breaking mechanism, but highly sensitive
to the sfermion charge. We compare the total cross sections for bremsstrahlung,
beamstrahlung, and laser backscattering photons to those in $e^+e^-$
annihilation. We find that the total cross section at a polarized photon
collider is larger than the $e^+e^-$ annihilation cross section up to the
kinematic limit of the photon collider.

</DOC>
<DOC>
<DOCNO> 116816 </DOCNO>
Energy Absorber R&D


  We describe the program of research and development being undertaken by a
consortium of Illinois university groups to develop liquid-hydrogen energy
absorbers for muon-beam cooling for a possible stored-muon-beam neutrino
factory.

</DOC>
<DOC>
<DOCNO> 116943 </DOCNO>
Optical Transition Radiation (OTR) Measurements of an Intense Pulsed


  We present the first time resolved OTR angular distribution measurements of
an intense pulsed electron beam (1.7 kA, 60 ns). These initial experiments on
the first axis of the Dual Axis Radiographic Hydro-Testing (DARHT) facility and
subsequent analysis, demonstrate the possibility to extract, from the data, the
energy and the divergence angle of a 3.8 and 20 MeV electrons.

</DOC>
<DOC>
<DOCNO> 69268 </DOCNO>
Minimal Model for Neutrino Masses and Mixings


  Working in the framework of three chiral neutrinos with Majorana masses, we
investigate a scenario first realized in an explicit model by Zee: that the
neutrino mass matrix is strictly off-diagonal in the flavor basis, with all its
diagonal entries precisely zero. This CP-conserving ansatz leads to two
relations among the three mixing angles $(\theta_1, \theta_2, \theta_3)$ and
two squared mass differences. We impose the constraint $|m_3^2 - m_2^2| \gg
|m^2_2 - m_1^2|$ to conform with experiment, which requires the $\theta_i$ to
lie nearby one of four 1-parameter domains in $\theta$-space. We exhibit the
implications for solar and atmospheric neutrino oscillations in each of these
cases. A unique version of the Zee {\it ansatz} survives confrontation with
experimental data, one which necessarily involves maximal just-so vacuum
oscillations of solar neutrinos.

</DOC>
<DOC>
<DOCNO> 11849 </DOCNO>
Random Berry Phase Magnetoresistance as a Probe of Interface Roughness


  The effect of silicon-oxide interface roughness on the weak-localization
magnetoconductance of a silicon MOSFET in a magnetic field, tilted with respect
to the interface, is studied. It is shown that an electron picks up a random
Berry's phase as it traverses a closed orbit. Effectively, due to roughness,
the electron sees an uniform field parallel to the interface as a random
perpendicular field. At zero parallel field the dependence of the conductance
on the perpendicular field has a well known form, the weak-localization
lineshape. Here the effect of applying a fixed parallel field on the lineshape
is analyzed. Many types of behavior are found including homogeneous broadening,
inhomogeneous broadening and a remarkable regime in which the change in
lineshape depends only on the magnetic field, the two length scales that
characterize the interface roughness and fundamental constants. Good agreement
is obtained with experiments that are in the homogeneous broadening limit. The
implications for using weak-localization magnetoconductance as a probe of
interface roughness, as proposed by Wheeler and coworkers, are discussed.

</DOC>
<DOC>
<DOCNO> 85634 </DOCNO>
An Sl(3,R) multiplet of 8-dimensional type II supergravity theories and


  The so-called ``massive 11-dimensional supergravity'' theory gives, for one
Killing vector, Romans' massive 10-dimensional supergravity in 10 dimensions,
for two Killing vectors an Sl(2,Z) multiplet of massive 9-dimensional
supergravity theories that can be obtained by standard generalized dimensional
reduction type IIB supergravity and has been shown to contain a gauged
supergravity. We consider a straightforward generalization of this theory to
three Killing vectors and a 3\times 3 symmetric mass matrix and show that it
gives an Sl(3,Z) multiplet of 8-dimensional supergravity theories that contain
an SO(3) gauged supergravity which is, in some way, the dual to the one found
by Salam and Sezgin by standard generalized dimensional reduction.

</DOC>
<DOC>
<DOCNO> 170798 </DOCNO>
Compression of quantum measurement operations


  We generalize recent work of Massar and Popescu dealing with the amount of
classical data that is produced by a quantum measurement on a quantum state
ensemble. In the previous work it was shown how spurious randomness generally
contained in the outcomes can be eliminated without decreasing the amount of
knowledge, to achieve an amount of data equal to the von Neumann entropy of the
ensemble. Here we extend this result by giving a more refined description of
what constitute equivalent measurements (that is measurements which provide the
same knowledge about the quantum state) and also by considering incomplete
measurements. In particular we show that one can always associate to a POVM
with elements a_j, an equivalent POVM acting on many independent copies of the
system which produces an amount of data asymptotically equal to the entropy
defect of an ensemble canonically associated to the ensemble average state and
the initial measurement (a_j). In the case where the measurement is not
maximally refined this amount of data is strictly less than the von Neumann
entropy, as obtained in the previous work. We also show that this is the best
achievable, i.e. it is impossible to devise a measurement equivalent to the
initial measurement (a_j) that produces less data. We discuss the
interpretation of these results. In particular we show how they can be used to
provide a precise and model independent measure of the amount of knowledge that
is obtained about a quantum state by a quantum measurement. We also discuss in
detail the relation between our results and Holevo's bound, at the same time
providing a new proof of this fundamental inequality.

</DOC>
<DOC>
<DOCNO> 174572 </DOCNO>
Coherent \pi^0 threshold production from the deuteron at Q^2 = 0.1


  First data on coherent threshold \pi^0 electroproduction from the deuteron
taken by the A1 Collaboration at the Mainz Microtron MAMI are presented. At a
four-momentum transfer of q^2=-0.1 GeV^2/c^2 the full solid angle was covered
up to a center-of-mass energy of 4 MeV above threshold. By means of a
Rosenbluth separation the longitudinal threshold s wave multipole and an upper
limit for the transverse threshold s wave multipole could be extracted and
compared to predictions of Heavy Baryon Chiral Perturbation Theory.

</DOC>
<DOC>
<DOCNO> 117394 </DOCNO>
Cold gas, the HI 21cm line and evolving galactic potentials


  Neutral hydrogen traces gravitational potentials. In the nearby universe,
21cm emission-line surveys show that the bulk of the HI resides in well-formed,
optically-luminous galaxies. At high redshift, 21cm line absorption against
background radio quasars occurs in gas-rich systems identified with the highest
HI column densities -- the ``damped Lyman alpha'' quasar absorption-line
systems. High spatial-resolution observations of the redshifted 21cm line
absorbers measure sizes and kinematics of the neutral absorbers.

</DOC>
<DOC>
<DOCNO> 178562 </DOCNO>
Nucleon-Nucleon Scattering in a Three Dimensional Approach


  The nucleon-nucleon (NN) t-matrix is calculated directly as function of two
vector momenta for different realistic NN potentials. To facilitate this a
formalism is developed for solving the two-nucleon Lippmann-Schwinger equation
in momentum space without employing a partial wave decomposition. The total
spin is treated in a helicity representation. Two different realistic NN
interactions, one defined in momentum space and one in coordinate space, are
presented in a form suited for this formulation. The angular and momentum
dependence of the full amplitude is studied and displayed. A partial wave
decomposition of the full amplitude it carried out to compare the presented
results with the well known phase shifts provided by those interactions.

</DOC>
<DOC>
<DOCNO> 85438 </DOCNO>
An alternative approach to the galactic dark matter problem


  We discuss scenarios in which the galactic dark matter in spiral galaxies is
described by a long range coherent field which settles in a stationary
configuration that might account for the features of the galactic rotation
curves. The simplest possibility is to consider scalar fields, so we discuss in
particular, two mechanisms that would account for the settlement of the scalar
field in a non-trivial configuration in the absence of a direct coupling of the
field with ordinary matter: topological defects, and spontaneous scalarization.

</DOC>
<DOC>
<DOCNO> 102069 </DOCNO>
Group completions via Hilbert schemes


  Let $X$ be a projective variety, homogeneous under a linear algebraic group.
We show that the diagonal of $X$ belongs to a unique irreducible component
$H_X$ of the Hilbert scheme of $X\times X$. Moreover, $H_X$ is isomorphic to
the ``wonderful completion'' of the connected automorphism group of $X$; in
particular, $H_X$ is non-singular. We describe explicitly the degenerations of
the diagonal in $X\times X$, that is, the points of $H_X$; these subschemes of
$X\times X$ are reduced and Cohen-Macaulay.

</DOC>
<DOC>
<DOCNO> 12980 </DOCNO>
Dynamic ultrametricity in finite dimensional spin glasses


  We show results of simulations of a weakly driven four dimensional Edwards-
Anderson spin glass, which presents clear signatures of dynamical
ultrametricity at low temperatures. The presence of a hierarchical organization
of time scales is evident from the appearance of a triangular relation between
correlations at three characteristic long times in the asymptotic limit of
small drive, and also in the scaling form of stationary correlations in this
regime. The differences between this scenario and known results of the aging
dynamics of the model are also analyzed.

</DOC>
<DOC>
<DOCNO> 122688 </DOCNO>
A Luminous Infrared Companion in the Young Triple System WL 20


  We present spatially resolved near-infrared and mid-infrared (1-25 microns)
imaging of the WL 20 triple system in the nearby (d=125 pc) rho Ophiuchi
star-forming cloud core. We find WL 20 to be a new addition to the rare class
of "infrared companion systems", with WL 20:E and WL 20:W displaying Class II
(T-Tauri star) spectral energy distributions (SEDs) and total luminosities of
0.61 and 0.39 L_sun, respectively, and WL 20:S, the infrared companion, with a
Class I (embedded protostellar) SED and a luminosity of 1.0-1.8 L_sun. WL 20:S
is found to be highly variable over timescales of years, to be extended (40 AU
diameter) at mid-infrared wavelengths, and to be the source of the centimeter
emission in the system. The photospheric luminosities, estimated from our data,
allow us to compare and test current pre-main-sequence evolutionary tracks. WL
20:E and WL 20:W fall into the region of the H-R diagram in which sources may
appear up to twice as old as they actually are using non-accreting tracks, a
fact which may reconcile the co-existence of two T-Tauri stars with an embedded
protostar in a triple system. The derived masses and observed projected
separations of the components of the WL 20 triple system indicate that it is in
an unstable dynamical configuration, and may therefore provide an example of
dynamical evolution during the pre-main-sequence phase.

</DOC>
<DOC>
<DOCNO> 39958 </DOCNO>
On the Velocity of Light Signals in the Deep Underwater Neutrino


  During the last few years deep underwater neutrino telescopes of a new
generation with dimensions close to 100 m or more were taken into operation.
For the correct track reconstruction and for the interpretation of light pulses
from calibration lasers one has to use the group velocity for light signals.
The difference between group velocity leads to an additional delay of about 10
ns for a distance of 100 m between light source and photjmultiplier. From the
time of the appearance of the first projects of deep underwater neutrino
telescopes in the middle of 70th this fact was never mentioned in the
literature.

</DOC>
<DOC>
<DOCNO> 178784 </DOCNO>
Quantum corrections for pion correlations involving resonance decays


  A method is presented to include quantum corrections into the calculation of
two-pion correlations for the case where particles originate from resonance
decays. The technique uses classical information regarding the space-time
points at which resonances are created. By evaluating a simple thermal model,
the method is compared to semiclassical techniques that assume exponential
decaying resonances moving along classical trajectories. Significant
improvements are noted when the resonance widths are broad as compared to the
temperature.

</DOC>
<DOC>
<DOCNO> 151640 </DOCNO>
Bosonic Fields in the String-like Defect Model


  We study localization of bosonic bulk fields on a string-like defect with
codimension 2 in a general space-time dimension in detail. We show that in
cases of spin 0 scalar and spin 1 vector fields there are an infinite number of
massless Kaluza-Klein (KK) states which are degenerate with respect to the
radial quantum number, but only the massless zero mode state among them is
coupled to fermion on the string-like defect. It is also commented on
interesting extensions of the model at hand to various directions such as
'little' superstring theory, conformal field theory and a supersymmetric
construction.

</DOC>
<DOC>
<DOCNO> 169812 </DOCNO>
Borromean Binding of Three or Four Bosons


  We estimate the ratio $R=g_{3}/g_{2}$ of the critical coupling constants
$g_{2}$ and $g_{3}$ which are required to achieve binding of 2 or 3 bosons,
respectively, with a short-range interaction, and examine how this ratio
depends on the shape of the potential. Simple monotonous potentials give
$R\simeq 0.8$. A wide repulsive core pushes this ratio close to R=1. On the
other hand, for an attractive well protected by an external repulsive barrier,
the ratio approaches the rigorous lower bound $R=2/3$. We also present results
for N=4 bosons, sketch the extension to $N>4$, and discuss various
consequences.

</DOC>
<DOC>
<DOCNO> 123205 </DOCNO>
Continuum Variability of Active Galactic Nuclei in the Optical-UV Range


  The variability of the continuum spectral energy distribution has been
analyzed for a complete magnitude-limited sample of quasars in Selected Area
57, observed at two epochs in the photographic $U$, $B_J$, $F$ and $N$ bands
with the Mayall 4m telescope at Kitt Peak. Changes $\delta \alpha$ of the
spectral slope $\alpha$ appear correlated with brightness variations $\delta
log f_{\nu}$ indicating an average hardening of the spectrum in the bright
phases. This confirms that the correlation of variability with redshift, found
in a single observing band, is due to intrinsic spectral changes. The average
observed $\delta \alpha - \delta log f_{\nu}$ relation is consistent with the
spectral change due to temperature variation of a black body of about $2.5
\cdot 10^4 K$.

</DOC>
<DOC>
<DOCNO> 100525 </DOCNO>
Mirror symmetry and quantization of abelian varieties


  The paper consists of two sections. The first section provides a new
definition of mirror symmetry of abelian varieties making sense also over
$p$-adic fields. The second section introduces and studies quantized
theta-functions with two-sided multipliers, which are functions on
non-commutative tori. This is an extension of an earlier work by the author. In
the Introduction and in the Appendix the constructions of this paper are put
into a wider context.

</DOC>
<DOC>
<DOCNO> 8513 </DOCNO>
Anomalous metallicity and electronic phase separation in the CsC60


  133Cs and 13C-NMR have been used to study the electronic properties of the
polymerized phase of CsC60 at ambient and under hydrostatic pressure. The
salient result of this study is the finding of fluctuations in the local field
at 133Cs site which are independent of the applied pressure and due to
thermally activated changes in the local electronic environment of 133Cs
nuclei. We establish that the phase separation between magnetic and nonmagnetic
domains observed in the low temperature state at ambient pressure is the result
of a slowing down of these fluctuations likely related to polaronic charge
excitations on the polymers.

</DOC>
<DOC>
<DOCNO> 71209 </DOCNO>
pNRQCD: review of selected results


  I review and discuss a selected sample of recent results in pNRQCD.

</DOC>
<DOC>
<DOCNO> 70848 </DOCNO>
\Lambda_c^+ production in polarized pp scattering and polarized gluon


  To extract information about the polarized gluon distribution, $\dg$, in the
nucleons, we propose \Lambda_c^+ productions in polarized pp scattering, p +
\vec{p} \to \vec{Lambda_c^+} + X, which will be observed at RHIC experiment
starting soon. For this process, we have calculated the spin correlation
differential cross section, d\Delta \sigma/d\pt, and the spin correlation
asymmetry defined by \A_ll \equiv [ d \Delta \sigma / d \pt ] / [ d \sigma /
d\pt ]. We have found that the \A_ll is sensitive to the polarized gluon
distribution in the nucleon and thus the process is promising for testing
\Delta G(x,Q^2).

</DOC>
<DOC>
<DOCNO> 9533 </DOCNO>
Renormalization of spectral lineshape and dispersion below Tc in


  Angle-resolved photoemission (ARPES) data in the superconducting state of
Bi2Sr2CaCu2O8+d show a kink in the dispersion along the zone diagonal, which is
related via a Kramers-Kronig analysis to a drop in the low-energy scattering
rate. As one moves towards (pi,0), this kink evolves into a spectral dip. The
occurrence of these anomalies in the dispersion and lineshape throughout the
zone indicate the presence of a new energy scale in the superconducting state.

</DOC>
<DOC>
<DOCNO> 71955 </DOCNO>
Scales and Phases in Particle Physics and Cosmology


  I describe and analyze the various energy scales that emerge from studying
the structure of the Standard Models of particle physics and cosmology.
Remarkably, save for the scale of the cosmological vacuum energy, all the
scales below the Fermi scale appear to be naturally associated with generalized
see-saw mechanisms. I also briefly discuss the known and presumed CP-violating
phases emerging from physics associated with these models and their physical
extensions. I end by commenting on the insights one might expect to gain from
experiment on these issues in the next decade.

</DOC>
<DOC>
<DOCNO> 85359 </DOCNO>
Action and Energy of the Gravitational Field


  We present a detailed examination of the variational principle for metric
general relativity as applied to a ``quasilocal'' spacetime region $\M$ (that
is, a region that is both spatially and temporally bounded). Our analysis
relies on the Hamiltonian formulation of general relativity, and thereby
assumes a foliation of $\M$ into spacelike hypersurfaces $\Sigma$. We allow for
near complete generality in the choice of foliation. Using a field--theoretic
generalization of Hamilton--Jacobi theory, we define the quasilocal
stress-energy-momentum of the gravitational field by varying the action with
respect to the metric on the boundary $\partial\M$. The gravitational
stress-energy-momentum is defined for a two--surface $B$ spanned by a spacelike
hypersurface in spacetime. We examine the behavior of the gravitational
stress-energy-momentum under boosts of the spanning hypersurface. The boost
relations are derived from the geometrical and invariance properties of the
gravitational action and Hamiltonian. Finally, we present several new examples
of quasilocal energy--momentum, including a novel discussion of quasilocal
energy--momentum in the large-sphere limit towards spatial infinity.

</DOC>
<DOC>
<DOCNO> 151819 </DOCNO>
Relativistic wave functions and energies for nonzero angular momentum


  Light-front dynamics (LFD) is a powerful approach to the theory of
relativistic composite systems (hadrons in the quark models and relativistic
nucleons in nuclei). Its explicitly covariant version has been recently applied
with success to describe the new CEBAF/TJNAF data on the deuteron
electromagnetic form factors. The solutions used in were however not obtained
from solving exactly the LFD equations but by means of a perturbative
calculation with respect to the non relativistic wave function. Since, a
consequent effort has been made to obtain exact solutions of LFD equations. The
first results concerning J=0 states in a scalar model have been published in
nucl-th/9912050. The construction of $J \ne 0$ states in LFD is complicated by
the two following facts. First, the generators of the spatial rotations contain
interaction and are thus difficult to handle. Second, one is always forced to
work in a truncated Fock space, and consequently, the Poincar\'e group
commutation relations between the generators -- ensuring the correct properties
of the state vector under rotation -- are in practice destroyed. In the
standard approach, with the light-front plane defined as $t+z=0$, this
violation of rotational invariance manifests by the fact that the energy
depends on the angular momentum projection on $z$-axis.
  We present here a method to construct $J\ne0$ states in the explicitly
covariant formulation of LFD and show how it leads to a restoration of
rotational invariance.

</DOC>
<DOC>
<DOCNO> 11061 </DOCNO>
A quantum Monte Carlo study of the one-dimensional ionic Hubbard model


  Quantum Monte Carlo methods are used to study a quantum phase transition in a
1D Hubbard model with a staggered ionic potential (D). Using recently
formulated methods, the electronic polarization and localization are determined
directly from the correlated ground state wavefunction and compared to results
of previous work using exact diagonalization and Hartree-Fock. We find that the
model undergoes a thermodynamic transition from a band insulator (BI) to a
broken-symmetry bond ordered (BO) phase as the ratio of U/D is increased. Since
it is known that at D = 0 the usual Hubbard model is a Mott insulator (MI) with
no long-range order, we have searched for a second transition to this state by
(i) increasing U at fixed ionic potential (D) and (ii) decreasing D at fixed U.
We find no transition from the BO to MI state, and we propose that the MI state
in 1D is unstable to bond ordering under the addition of any finite ionic
potential. In real 1D systems the symmetric MI phase is never stable and the
transition is from a symmetric BI phase to a dimerized BO phase, with a
metallic point at the transition.

</DOC>
<DOC>
<DOCNO> 116437 </DOCNO>
The Induced Self-Purification of Creeks and Rivers


  The clean-up of several Creeks and Rivers by induction of a self-purification
process was provided. The process took place at all the sites studied with the
up to 100% resulted removal of polluting agents depending on the site and
nature of the contaminant. The self-purification mechanism could be used for
drinking and technical water preparation.

</DOC>
<DOC>
<DOCNO> 84696 </DOCNO>
Two-Dilaton Theories in Two Dimensions from Dimensional Reduction


  Dimensional reduction of generalized gravity theories or string theories
generically yields dilaton fields in the lower-dimensional effective theory.
Thus at the level of D=4 theories, and cosmology many models contain more than
just one scalar field (e.g. inflaton, Higgs, quintessence). Our present work is
restricted to two-dimensional gravity theories with only two dilatons which
nevertheless allow a large class of physical applications.
  The notions of factorizability, simplicity and conformal simplicity, Einstein
form and Jordan form are the basis of an adequate classification. We show that
practically all physically motivated models belong either to the class of
factorizable simple theories (e.g. dimensionally reduced gravity, bosonic
string) or to factorizable conformally simple theories (e.g. spherically
reduced Scalar-Tensor theories). For these theories a first order formulation
is constructed straightforwardly. As a consequence an absolute conservation law
can be established.

</DOC>
<DOC>
<DOCNO> 99875 </DOCNO>
Super-Brownian motion with reflecting historical paths


  We consider super-Brownian motion whose historical paths reflect from each
other, unlike those of the usual historical super-Brownian motion. We prove
tightness for the family of distributions corresponding to a sequence of
discrete approximations but we leave the problem of uniqueness of the limit
open. We prove a few results about path behavior for processes under any limit
distribution. In particular, we show that for any $\gamma>0$, a "typical"
increment of a reflecting historical path over a small time interval $\Delta t$
is not greater than $(\Delta t)^{3/4 - \gamma}$.

</DOC>
<DOC>
<DOCNO> 68610 </DOCNO>
Particle production in the oscillating inflation model


  We investigate the particle production of a scalar field $\chi$ coupled to an
inflaton field $\phi$ ($g^2\phi^2\chi^2/2$) in the {\it oscillating inflation}
model, which was recently proposed by Damour and Mukhanov. Although the
fluctuation of the $\phi$ field can be effectively enhanced during a stage of
the oscillating inflation, the maximum fluctuation is suppressed as the
critical value $\phi_c$ which indicates the scale of the core part of the
inflaton potential decreases, in taking into account the back reaction effect
of created particles. As for the $\chi$ particle production, we find that
larger values of the coupling constant $g$ are required to lead to an efficient
parametric resonance with the decrease of $\phi_c$, because an effective mass
of inflaton around the minimum of its potential becomes larger. However, it is
possible to generate the superheavy $\chi$ particle whose mass is greater than
$10^{14}$ GeV, which would result in an important consequence for the GUT
baryogenesis.

</DOC>
<DOC>
<DOCNO> 122637 </DOCNO>
The Turbulent Shock Origin of Proto--Stellar Cores


  The fragmentation of molecular clouds (MC) into protostellar cores is a
central aspect of the process of star formation. Because of the turbulent
nature of super-sonic motions in MCs, it has been suggested that dense
structures such as filaments and clumps are formed by shocks in a turbulent
flow. In this work we present strong evidence in favor of the turbulent origin
of the fragmentation of MCs. The most generic result of turbulent fragmentation
is that dense post shock gas traces a gas component with a smaller velocity
dispersion than lower density gas, since shocks correspond to regions of
converging flows, where the kinetic energy of the turbulent motion is
dissipated. Using synthetic maps of spectra of molecular transitions, computed
from the results of numerical simulations of super--sonic turbulence, we show
that the dependence of velocity dispersion on gas density generates an
observable relation between the rms velocity centroid and the integrated
intensity (column density), Sigma(V_0)-I, which is indeed found in the
observational data. The comparison between the theoretical model (maps of
synthetic 13CO spectra), with 13CO maps from the Perseus, Rosette and Taurus MC
complexes, shows excellent agreement in the Sigma(V_0)-I relation. The
Sigma(V_0)-I relation of different observational maps with the same total rms
velocity are remarkably similar, which is a strong indication of their origin
from a very general property of the fluid equations, such as the turbulent
fragmentation process.

</DOC>
<DOC>
<DOCNO> 85601 </DOCNO>
Theoretical Necessity of an External Scalar Field in the Kaluza-Klein


  We show that the principle of least action is generally inconsistent with the
usual Kaluza-Klein program, the higher dimensional Einstein-Hilbert action
being unbounded from below. This inconsistency is also present in other
theories with higher dimensions like supergravity. Hence, we conclude to the
necessity of an external scalar field to compensate this flaw.

</DOC>
<DOC>
<DOCNO> 12497 </DOCNO>
Continuum in the spin excitation spectrum of a Haldane chain, observed


  The spin excitation continuum, expected to dominate the low-energy
fluctuation spectrum in the Haldane spin chain around the Brillouin zone
center, q=0, is directly observed by inelastic magnetic neutron scattering in
the S=1 quasi-1D antiferromagnet CsNiCl3. We find that the single mode
approximation fails, and that a finite energy width appears in the dynamic
correlation function S(q,omega) for q < 0.5pi. The width increases with
decreasing q, while S(q,omega) acquires an asymmetric shape qualitatively
similar to that predicted for the 2-magnon continuum in the nonlinear
sigma-model.

</DOC>
<DOC>
<DOCNO> 9024 </DOCNO>
Diffusion as mixing mechanism in granular materials


  We present several numerical results on granular mixtures. In particular, we
examine the efficiency of diffusion as a mixing mechanism in these systems. The
collisions are inelastic and to compensate the energy loss, we thermalize the
grains by adding a random force. Starting with a segregated system, we show
that uniform agitation (heating) leads to a uniform mixture of grains of
different sizes. We define a characteristic mixing time, $\tau_{mix}$, and
study theoretically and numerically its dependence on other parameters like the
density. We examine a model for bidisperse systems for which we can calculate
some physical quantities. We also examine the effect of a temperature gradient
and demonstrate the appearance of an expected segregation.

</DOC>
<DOC>
<DOCNO> 150424 </DOCNO>
Finite Volume Spectrum of Sine-Gordon Model and its Restrictions


  In this thesis, we review recent progresses on Nonlinear Integral Equation
approach to finite size effects in two dimensional integrable quantum field
theories, with emphasis to Sine-Gordon/Massive Thirring model and restrictions
to minimal models perturbed by $\Phi_{1,3}$. Exact calculations of the
dependence of energy levels on the size are presented for vacuum and many
excited states.

</DOC>
<DOC>
<DOCNO> 118439 </DOCNO>
Achieving a wide field near infrared camera for the Calar Alto 3.5m


  The ongoing development of large infrared array detectors has enabled wide
field, deep surveys to be undertaken. There are, however, a number of
challenges in building an infrared instrument which has both excellent optical
quality and high sensitivity over a wide field. We discuss these problems in
the context of building a wide field imaging camera for the 3.5m telescope at
Calar Alto with the new 2K*2K HgCdTe HAWAII-2 focal plane array. Our final
design is a prime focus camera with a 15' field-of-view, called Omega 2000. To
achieve excellent optical quality over the whole field, we have had to dispense
with the reimaging optics and cold Lyot stop. We show that creative baffling
schemes, including the use of undersized baffles, can compensate for the lost K
band sensitivity. A moving baffle will be employed in Omega 2000 to allow full
transmission in the non-thermal J and H bands.

</DOC>
<DOC>
<DOCNO> 152515 </DOCNO>
Stepwise Projection: Toward Brane Setups for Generic Orbifold


  The construction of brane setups for the exceptional series E6,E7,E8 of SU(2)
orbifolds remains an ever-haunting conundrum. Motivated by techniques in some
works by Muto on non-Abelian SU(3) orbifolds, we here provide an algorithmic
outlook, a method which we call stepwise projection, that may shed some light
on this puzzle. We exemplify this method, consisting of transformation rules
for obtaining complex quivers and brane setups from more elementary ones, to
the cases of the D-series and E6 finite subgroups of SU(2). Furthermore, we
demonstrate the generality of the stepwise procedure by appealing to Frobenius'
theory of Induced Representations. Our algorithm suggests the existence of
generalisations of the orientifold plane in string theory.

</DOC>
<DOC>
<DOCNO> 179018 </DOCNO>
Helicity Amplitudes and Sum Rules for Real and Virtual Photons


  Results of the recently developed unitary isobar model (MAID) are presented
for helicity amplitudes, spin asymmetries, structure functions and relevant sum
rules for real and virtual photons in the resonance region. Our evaluation of
the energy-weighted integrals is in good agreement for the proton but shows big
discrepancies for the neutron.

</DOC>
<DOC>
<DOCNO> 69877 </DOCNO>
Mesonic fluctuations in a nonlocal Nambu-Jona-Lasinio model


  The effects of meson fluctuations are studied in a nonlocal generalization of
the Nambu-Jona-Lasinio model, by including terms of next-to-leading order (NLO)
in 1/N_c. In the model with only scalar and pseudoscalar interactions NLO
contributions to the quark condensate are found to be very small. This is a
result of cancellation between virtual mesons and Fock terms, which occurs for
the parameter sets of most interest. In the quark self-energy, similar
cancellations arise in the tadpole diagrams, although not in other NLO pieces
which contribute at the \sim 25% level. The effects on pion properties are also
found to be small. NLO contributions from real $\pi\pi$ intermediate states
increase the sigma meson mass by $\sim 30%$. In an extended model with vector
and axial interactions, there are indications that NLO effects could be larger.

</DOC>
<DOC>
<DOCNO> 83156 </DOCNO>
Reasoning with Higher-Order Abstract Syntax in a Logical Framework


  Logical frameworks based on intuitionistic or linear logics with higher-type
quantification have been successfully used to give high-level, modular, and
formal specifications of many important judgments in the area of programming
languages and inference systems. Given such specifications, it is natural to
consider proving properties about the specified systems in the framework: for
example, given the specification of evaluation for a functional programming
language, prove that the language is deterministic or that evaluation preserves
types. One challenge in developing a framework for such reasoning is that
higher-order abstract syntax (HOAS), an elegant and declarative treatment of
object-level abstraction and substitution, is difficult to treat in proofs
involving induction. In this paper, we present a meta-logic that can be used to
reason about judgments coded using HOAS; this meta-logic is an extension of a
simple intuitionistic logic that admits higher-order quantification over simply
typed lambda-terms (key ingredients for HOAS) as well as induction and a notion
of definition. We explore the difficulties of formal meta-theoretic analysis of
HOAS encodings by considering encodings of intuitionistic and linear logics,
and formally derive the admissibility of cut for important subsets of these
logics. We then propose an approach to avoid the apparent tradeoff between the
benefits of higher-order abstract syntax and the ability to analyze the
resulting encodings. We illustrate this approach through examples involving the
simple functional and imperative programming languages PCF and PCF:=. We
formally derive such properties as unicity of typing, subject reduction,
determinacy of evaluation, and the equivalence of transition semantics and
natural semantics presentations of evaluation.

</DOC>
<DOC>
<DOCNO> 101483 </DOCNO>
On the genus of a maximal curve


  Previous results on genera g of F_{q^2}-maximal curves are improved: (1)
Either g\leq (q^2-q+4)/6, or g=\lfloor(q-1)^2/4\rfloor, or g=q(q-1)/2; (2) The
hypothesis on the existence of a particular Weierstrass point in \cite{at} is
proved; (3) For q\equiv 1\pmod{3}, q\ge 13, no F_{q^2}-maximal curve of genus
(q-1)(q-2)/3 exists; (4) For q\equiv 2\pmod{3}, q\ge 11, the non-singular
F_{q^2}-model of the plane curve of equation y^q+y=x^{(q+1)/3} is the unique
F_{q^2}-maximal curve of genus g=(q-1)(q-2)/6; (5) Assume \dim(\cD_\cX)=5, and
char(\fq)\geq 5. For q\equiv 1\pmod{4}, q\geq 17, the Fermat curve of equation
x^{(q+1)/2}+y^{(q+1)/2}+1=0 is the unique F_{q^2}-maximal curve of genus
g=(q-1)(q-3)/8. For q\equiv 3\pmod{4}, q\ge 19, there are exactly two
F_{q^2}-maximal curves of genus g=(q-1)(q-3)/8, namely the above Fermat curve
and the non-singular F_{q^2}-model of the plane curve of equation
y^q+y=x^{(q+1)/4}. The above results provide some new evidences on maximal
curves in connection with Castelnuovo's bound and Halphen's theorem, especially
with extremal curves; see for instance the conjecture stated in Introduction.

</DOC>
<DOC>
<DOCNO> 118931 </DOCNO>
X-ray Images of Hot Accretion Flows


  We consider the X-ray emission due to bremsstrahlung processes from hot, low
radiative-efficiency accretion flows around supermassive and galactic black
holes. We calculate surface brightness profiles and Michelson visibility
functions for a range of density profiles, rho ~ r^(-3/2+p), with 0 < p < 1, to
allow for the presence of outflows. We find that although the 1 keV emitting
region in these flows can always extend up to 10^6 Schwarzschild radii (R_S),
their surface brightness profiles and visibility functions are strongly
affected by the specific density profile. The advection-dominated solutions
with no outflows (p=0) lead to centrally peaked profiles with characteristic
sizes of only a few tens of R_S. Solutions with strong outflows (p~1) lead to
flat intensity profiles with significantly larger characteristic sizes of up to
10^6 R_S. This implies that low luminosity galactic nuclei, such as M87, may
appear as extended X-ray sources when observed with current X-ray imaging
instruments. We show that X-ray brightness profiles and their associated
visibility functions may be powerful probes for determining the relevant mode
of accretion and, in turn, the properties of hot accretion flows. We discuss
the implications of our results for observations with the Chandra X-ray
Observatory and the planned X-ray interferometer MAXIM.

</DOC>
<DOC>
<DOCNO> 99533 </DOCNO>
Polytopal linear algebra


  We investigate similarities between the category of vector spaces and that of
polytopal algebras, containing the former as a full subcategory. In Section 2
we introduce the notion of a polytopal Picard group and show that it is trivial
for fields. The coincidence of this group with the ordinary Picard group for
general rings remains an open question. In Section 3 we survey some of the
previous results on the automorphism groups and retractions. These results
support a general conjecture proposed in Section 4 about the nature of
arbitrary homomorphisms of polytopal algebras. Thereafter a further
confirmation of this conjecture is presented by homomorphisms defined on
Veronese singularities.
  This is a continuation of the project started in our papers "Polytopal linear
groups" (J. Algebra 218 (1999), 715--737), "Polytopal linear retractions"
preprint, math.AG/0001049) and "Polyhedral algebras, arrangements of toric
varieties, and their groups" (preprint,
http://www.mathematik.uni-osnabrueck.de/K-theory/0232/index.html). The higher
$K$-theoretic aspects of polytopal linear objects will be treated in
"Polyhedral $K$-theory" (in preparation).

</DOC>
<DOC>
<DOCNO> 13520 </DOCNO>
Phase Transition of a Heisenberg Spin-Glass Model in Three Dimensions


  We study the phase transition of the $\pm J$ Heisenberg model in three
dimensions. Using a dynamical simulation method that removes a drift of the
system, the existence of the spin-glass (SG) phase at low temperatures is
suggested. The transition temperature is estimated to be $T_{\rm SG} \sim
0.18J$ from both equilibrium and off-equilibrium Monte-Carlo simulations. Our
result contradicts the chirality mechanism of the phase transition reported
recently by Kawamura which claims that it is not the spins but the chiralities
of the spins that are ordered in Heisenberg SG systems.

</DOC>
<DOC>
<DOCNO> 69401 </DOCNO>
Effective action for the order parameter of the deconfinement transition


  The effective action for the Polyakov loop serving as an order parameter for
deconfinement is obtained in one-loop approximation to second order in a
derivative expansion. The calculation is performed in $d\geq 4$ dimensions,
mostly referring to the gauge group SU(2). The resulting effective action is
only capable of describing a deconfinement phase transition for
$d>d_{\text{cr}}\simeq 7.42$. Since, particularly in $d=4$, the system is
strongly governed by infrared effects, it is demonstrated that an additional
infrared scale such as an effective gluon mass can change the physical
properties of the system drastically, leading to a model with a deconfinement
phase transition.

</DOC>
<DOC>
<DOCNO> 116590 </DOCNO>
A Hybrid Algebraic/Schr\"odinger Approach to the 2D Franck-Condon


  We use recent results regarding the geometry of the U(3) bosonic algebraic
model to motivate a hybrid algebraic-Schr\"odinger approach to the 2D
Franck-Condon problem analogous to 1D approaches. This approach allows one to
analyze bent to linear Franck-Condon transitions of triatomic molecules as well
as clarifies the angular momentum dependance of the Franck-Condon intensities.

</DOC>
<DOC>
<DOCNO> 13328 </DOCNO>
SET based experiments for HTSC materials


  The cuprates seem to exhibit statistics, dimensionality and phase transitions
in novel ways. The nature of excitations [i.e. quasiparticle or collective],
spin-charge separation, stripes [static and dynamics], inhomogeneities,
psuedogap, effect of impurity dopings [e.g. Zn, Ni] and any other phenomenon in
these materials must be consistently understood. In this note we suggest Single
Electron Tunneling Transistor [SET] based experiments to understand the role of
charge dynamics in these systems. Assuming that SET operates as an efficient
charge detection system we can expect to understand the underlying physics of
charge transport and charge fluctuations in these materials for a range of
doping.
  Experiments such as these can be classed in a general sense as mesoscopic and
nano characterization of cuprates and related materials.

</DOC>
<DOC>
<DOCNO> 72269 </DOCNO>
Electron and Neutron Electric Dipole Moments in the Focus Point Scenario


  We estimate the electron and neutron electric dipole moments in the focus
point scenario of the minimal SUGRA model corresponding to large sfermion
masses and moderate to large $\tan\beta$. There is a viable region of moderate
fine-tuning in the parameter space, around $\tan\beta \simeq 5$, where the
experimental limits on these electric dipole moments can be satisfied without
assuming unnaturally small phase angles. But the fine-tuning constraints become
more severe for $\tan\beta > 10$.

</DOC>
<DOC>
<DOCNO> 11227 </DOCNO>
Thickness dependence of the stability of the charge-ordered state in


  Thin films of the charge-ordered (CO) compound Pr$_{0.5}$Ca$_{0.5}$MnO$_{3}$
have been deposited onto (100)-oriented SrTiO$_{3}$ substrates using the Pulsed
Laser Deposition technique. Magnetization and transport properties are measured
when the thickness of the film is varied. While the thinner films do not
exhibit any temperature induced insulator-metal transition under an applied
magnetic field up to 9T, for thickness larger than 1100\UNICODE{0xc5} a 5T
magnetic field is sufficient to melt the CO state. For this latest film, we
have measured the temperature-field phase diagram. Compared to the bulk
material, it indicates that the robustness of the CO state in thin films is
strongly depending on the strains and the thickness. We proposed an explanation
based on the distortion of the cell of the film.

</DOC>
<DOC>
<DOCNO> 10567 </DOCNO>
Compaction of a granular material under cyclic shear


  In this paper we present experimental results concerning the compaction of a
granular assembly of spheres under periodic shear deformation. The dynamic of
the system is slow and continuous when the amplitude of the shear is constant,
but exhibits rapid evolution of the volume fraction when a sudden change in
shear amplitude is imposed. This rapid response is shown to be to be
uncorrelated with the slow compaction process.

</DOC>
<DOC>
<DOCNO> 11226 </DOCNO>
Scaling of Crack Surfaces and Implications on Fracture Mechanics


  The scaling laws describing the roughness development of crack surfaces are
incorporated into the Griffith criterion. We show that, in the case of a
Family-Vicsek scaling, the energy balance leads to a purely elastic brittle
behavior. On the contrary, it appears that an anomalous scaling reflects a
R-curve behavior associated to a size effect of the critical resistance to
crack growth in agreement with the fracture process of heterogeneous brittle
materials exhibiting a microcracking damage.

</DOC>
<DOC>
<DOCNO> 119654 </DOCNO>
Exploring the evolution of spiral galaxies


  We have constructed a family of simple models for spiral galaxy evolution to
allow us to investigate observational trends in star formation history with
galaxy parameters. The models are used to generate broad band colours from
which ages and metallicities are derived in the same way as the data. We
generate a grid of model galaxies and select only those which lie in regions of
parameter space covered by the sample. The data are consistent with the
proposition that the star formation history of a region within a galaxy depends
primarily on the local surface density of the gas but that one or two
additional ingredients are required to fully explain the observational data.
The observed age gradients appear steeper than those produced by the density
dependent star formation law, indicating that the star formation law or infall
history must vary with galactocentric radius. Furthermore, the
metallicity-magnitude and age-magnitude correlations are not reproduced by a
local density dependence alone. These correlations require one or both of the
following: (i) a combination of mass dependent infall and metal enriched
outflow, or (ii) a mass dependent galaxy formation epoch. Distinguishing these
possibilities on the basis of current data is extremely difficult.

</DOC>
<DOC>
<DOCNO> 12783 </DOCNO>
Epidemic spreading in scale-free networks


  The Internet, as well as many other networks, has a very complex connectivity
recently modeled by the class of scale-free networks. This feature, which
appears to be very efficient for a communications network, favors at the same
time the spreading of computer viruses. We analyze real data from computer
virus infections and find the average lifetime and prevalence of viral strains
on the Internet. We define a dynamical model for the spreading of infections on
scale-free networks, finding the absence of an epidemic threshold and its
associated critical behavior. This new epidemiological framework rationalize
data of computer viruses and could help in the understanding of other spreading
phenomena on communication and social networks.

</DOC>
<DOC>
<DOCNO> 100320 </DOCNO>
Compact range property and operators on $C^*$-algebras


  We prove that a Banach space $E$ has the compact range property (CRP) if and
only if for any given $C^*$-algebra $\cal A$, every absolutely summing operator
from $\cal A$ into $E$ is compact.

</DOC>
<DOC>
<DOCNO> 70338 </DOCNO>
B->rho pi decays, resonant and nonresonant contributions


  We point out that a new contribution to B decays to three pions is relevant
in explaining recent data from the CLEO and BABAR collaborations, in particular
the results on quasi-two-body decays via a rho meson. We also discuss the
relevance of these contribution to the measurement of CP violations.

</DOC>
<DOC>
<DOCNO> 101746 </DOCNO>
Search for Three Forged Coins


  Suppose we are given a set of t coins which look identical, but a known
number s of them are counterfeit, with a known weight different from the
others. Our problem is to locate the counterfeits by weighing subsets of the t
coins, with as few weighings as possible. Despite a large literature on this
problem, it remains wide open for s>2.
  In this paper, we give an efficient sequential weighing algorithm for the
case s=3, with an average of 1.75 weighings per bit of t, as t approaches
infinity. (It is known that any algorithm must have more than 1.5 weighings per
bit.) We use our algorithm to give an efficient channel coding for the
three-sender multiple-access adder channel with feedback.

</DOC>
<DOC>
<DOCNO> 80763 </DOCNO>
One-Flavour Hybrid Monte Carlo with Wilson Fermions


  The Wilson fermion determinant can be written as product of the determinants
of two hermitian positive definite matrices. This formulation allows to
simulate non-degenerate quark flavors by means of the hybrid Monte Carlo
algorithm. A major numerical difficulty is the occurrence of nested inversions.
We construct a Uzawa iteration scheme which treats the nested system within one
iterative process.

</DOC>
<DOC>
<DOCNO> 10593 </DOCNO>
Theory of Luminescence Spectra of High-Density Electron-Hole Systems:


  We present a unified theory of luminescence spectra for highly excited
semiconductors, which is applicable both to the electron-hole BCS state and to
the exciton Bose-Einstein condensate. The crossover behavior between
electron-hole BCS state and exciton Bose-Einstein condensate clearly manifests
itself in the calculated luminescence spectra. The analysis is based on the
Bethe-Salpeter equation combined with the generalized
random-phase-approximation, which enables us to consider the multiple Coulomb
scattering and the quantum fluctuation associated with the center-of-mass
motion of electron-hole pairs. In the crossover regime, the calculated spectra
are essentially different from results obtained by the BCS-like mean-field
theory and the interacting Boson model. In particular, it is found that the
broad spectrum, arising from the recombination of electron-hole BCS state,
splits into the P- and P_2-luminescence bands with decreasing the particle
density. The dependence of these bands on the carrier density is in good
agreement with experiments for highly excited semiconductors.

</DOC>
<DOC>
<DOCNO> 101885 </DOCNO>
A deformation of Hermite polynomials


  We propose and study the properties of a set of polynomials $M_{n\alpha, H\
}^{s}(z)$, $C_{n\alpha, H}^{s}(z)$ $W_{n\alpha, H}^{s}(z)$ with $n,s\in N$
$;\alpha =\pm 1;$and where $H$ stands for Hermite ; the ''root '' polynomial
>.These polynomials are obtained from a deformation of Hermite polynomials
$H_{n}(z).$The structure underlying the deformation seems quite general and not
only restricted to Hermite polynomials.

</DOC>
<DOC>
<DOCNO> 8129 </DOCNO>
Large and small Density Approximations to the thermodynamic Bethe Ansatz


  We provide analytical solutions to the thermodynamic Bethe ansatz equations
in the large and small density approximations. We extend results previously
obtained for leading order behaviour of the scaling function of affine Toda
field theories related to simply laced Lie algebras to the non-simply laced
case. The comparison with semi-classical methods shows perfect agreement for
the simply laced case. We derive the Y-systems for affine Toda field theories
with real coupling constant and employ them to improve the large density
approximations. We test the quality of our analysis explicitly for the
Sinh-Gordon model and the $(G_2^{(1)},D_4^{(3)})$-affine Toda field theory.

</DOC>
<DOC>
<DOCNO> 100409 </DOCNO>
Compactness Theorems for Geometric Packings


  Moser asked whether the collection of rectangles of dimensions 1 x 1/2, 1/2 x
1/3, 1/3 x 1/4, ..., whose total area equals 1, can be packed into the unit
square without overlap, and whether the collection of squares of side lengths
1/2, 1/3, 1/4, ... can be packed without overlap into a rectangle of area
pi^2/6-1. Computational investigations have been made into packing these
collections into squares of side length 1+epsilon and rectangles of area
pi^2/6-1+epsilon, respectively, and one can consider the apparently weaker
question whether such packings are possible for every positive number epsilon.
In this paper we establish a general theorem on sequences of geometrical
packings that implies in particular that the ``for every epsilon'' versions of
these two problems are actually equivalent to the original tiling problems.

</DOC>
<DOC>
<DOCNO> 68876 </DOCNO>
About the Mixing and CP Violation in Neutrino System


  Suppose the geometrical explaination to the weak CP phase in quark sector is
also valid for neutrinos, the mixing and CP violation in neutrino system are
discussed. We find a larger $J_{CP}$ than $3\times 10^{-3}$ implys the
large-mixing solution for solar neutrino problem. In case of bi-maximal mixing,
we predict relative large CP violation with $J_{CP}$ larger than $10^{-3}$ in
neutrino system, except the third mixing angle approachs to 0 or $\pi/2$ very
closely.

</DOC>
<DOC>
<DOCNO> 120325 </DOCNO>
Dust Distribution in Gas Disks. A Model for the Ring Around HR 4796A


  There have been several model analyses of the near and mid IR flux from the
circumstellar ring around HR4796A. In the vicinity of a young star, the
possibility that the dust ring is embedded within a residual protostellar gas
disk cannot be ruled out. In a gas-rich environment, larger sizes ($>100 \mu
m$) are needed for the particles to survive the radiative blow out. The total
dust mass required to account for the IR flux is $< 10^{-1} M_\oplus$. The
combined influence of gas and stellar radiation may also account for the
observed sharp inner boundary and rapidly fading outer boundary of the ring.
The pressure gradient induced by a small (10%) amplitude variation in the
surface density distribution of a low-mass gaseous disk would be sufficient to
modify the rotation speed of the gas.

</DOC>
<DOC>
<DOCNO> 12131 </DOCNO>
First- and second-order phase transitions in a driven lattice gas with


  A lattice gas with infinite repulsion between particles separated by $\leq 1$
lattice spacing, and nearest-neighbor hopping dynamics, is subject to a drive
favoring movement along one axis of the square lattice. The equilibrium (zero
drive) transition to a phase with sublattice ordering, known to be continuous,
shifts to lower density, and becomes discontinuous for large bias. In the
ordered nonequilibrium steady state, both the particle and order-parameter
densities are nonuniform, with a large fraction of the particles occupying a
jammed strip oriented along the drive. The relaxation exhibits features
reminiscent of models of granular and glassy materials.

</DOC>
<DOC>
<DOCNO> 150480 </DOCNO>
The Interaction of Two Hopf Solitons


  This Letter deals with topological solitons in an O(3) sigma model in three
space dimensions (with a Skyrme term to stabilize their size). The solitons are
classified topologically by their Hopf number N. The N=2 sector is studied; in
particular, for two solitons far apart, there are three ``attractive
channels''. Viewing the solitons as dipole pairs enables one to predict the
force between them. Relaxing in the attractive channels leads to various static
2-soliton solutions.

</DOC>
<DOC>
<DOCNO> 13533 </DOCNO>
Electronic Structure of the Chevrel-Phase Compounds


  We have studied the electronic structure of two Chevrel-phase compounds,
Mo$_6$Se$_{7.5}$ and Sn$_{1.2}$Mo$_6$Se$_{7.5}$, by combining photoemission
spectroscopy and band-structure calculations. Core-level spectra taken with
x-ray photoemission spectroscopy show systematic core-level shifts, which do
not obey a simple rigid-band model. The inverse photoemission spectra imply the
existence of an energy gap located $\sim 1$ eV above the Fermi level, which is
a characteristic feature of the electronic structure of the Chevrel compounds.
Quantitative comparison between the photoemission spectra and the
band-structure calculations have been made. While good agreement between theory
and experiment in the wide energy range was obtained as already reported in
previous studies, we found that the high density of states near the Fermi level
predicted theoretically due to the Van Hove singularity is considerably reduced
in the experimental spectra taken with higher energy resolution than in the
previous reports. Possible origins are proposed to explain this observation.

</DOC>
<DOC>
<DOCNO> 13960 </DOCNO>
Time evolution of tetragonal-orthorhombic ferroelastics


  We study numerically the time evolution of two-dimensional (2D) domain
patterns in proper tetragonal-orthorhombic (T-O) ferroelastics. Our results,
found by solving equations of motion derived from classical elasticity theory,
disagree with those found by other methods. We study first the growth of the 2D
nucleus resulting from homogeneous nucleation events. The later shape of the
nucleus is largely independent of how it was nucleated. In soft systems, the
nucleus forms a flower-like pattern. In stiff systems, which seem to be more
realistic, it forms an X shape with twinned arms in the 110 and \110
directions. Second, we study the relaxation that follows completion of the
phase transition; at these times, the T phase has disappeared and both O
variants are present, segregated into domains separated by domain walls. We
observe a variety of coarsening mechanisms, most of them counterintuitive.

</DOC>
<DOC>
<DOCNO> 116586 </DOCNO>
A Nonstandard Derivation for the Special Theory of Relativity


  Using properties of the nonstandard physical world, a new fundamental
derivation for all of the effects of the Special Theory of Relativity is given.
This fundamental derivation removes all the contradictions and logical
difficulties in the original derivation and leads to the fundamental
expressions from which Prokhovnik derives the basic transformations. However,
it is shown that the correct interpretation is completely distinct from
Prokhovnik's. It is shown that the Special Theory effects are but
manifestations of the interaction between our natural world and a nonstandard
substratum. This derivation eliminates the controversy associated with any
physically unexplained universal time dilation and length contraction. It is
shown that there is no such thing as a universal time dilation and length
contraction but, rather, there are alterations in pure numerical quantities
associated with an electromagnetic interaction with a NSP-world substratum.

</DOC>
<DOC>
<DOCNO> 11546 </DOCNO>
Beyond the Wigner Distribution: Schr{\"o}dinger Equations and Terrace


  The so-called generalized Wigner distribution has earlier been shown to be an
excellent approximation for the terrace width distribution (TWD) of vicinal
surfaces characterized by step-step interactions that are perpendicular to the
average step direction and fall off as the inverse square of the step spacing.
In this paper we show that the generalized Wigner distribution corresponds to a
mean-field treatment of a single step, discuss generalizations to more general
step-step interactions, and show that the mean-field predictions are in good
agreement with TWDs derived from numerical transfer-matrix calculations and
Monte Carlo simulations. We also show that this mean-field treatment allows the
step-step interaction to be extracted from experimental TWDs.

</DOC>
<DOC>
<DOCNO> 100298 </DOCNO>
Projective normality of Abelian threefolds


  In this article, we show that very ample line bundles of type (1,1,d) on an
abelian threefold A, with NS(A)\simeq \ze, give projectively normal embeddings,
if d=22,26 or when d\geq 28.

</DOC>
<DOC>
<DOCNO> 120272 </DOCNO>
Discovery of Non-Thermal X-Rays from the Shell of RCW86


  We report the ASCA (Advanced Satellite for Cosmology and Astrophysics)
results of RCW 86, a shell-like supernova remnant (SNR). The bright region in
the X-ray band traces the radio clumpy shell, although details of the structure
are different. The X-ray spectrum from each part of the shell can not be fitted
to a thin thermal plasma model, but requires, at least three components: a low
temperature plasma of 0.3 keV, high temperature plasma of > several keV, and a
power-law component with a photon index = 3. The abundances of O, Ne, Mg and Si
are significantly higher than that of Fe, indicating that RCW 86 is a type II
SNR. The absorption column of 3e21 H cm^-2 indicates the distance to the SNR to
be several kpc. The power-law component can be interpreted to be synchrotron
radiation of high energy electrons. Assuming energy density equipartition
between the magnetic field and the electrons, and using the radio and X-ray
spectra, we argue that high energy electrons are accelerated up to 20 TeV. The
acceleration efficiency is, however, different from shell to shell.

</DOC>
<DOC>
<DOCNO> 116470 </DOCNO>
Scaled Universe II


  In an earlier paper we had pointed out that Quantum Mechanical type effects
are seen at different scales in the macro universe also. In this paper we
obtain a rationale for this, which lies in the picture of bound material
systems, spanning a Compton wavelength type extent, separated by much larger
and relatively much less dense distances.

</DOC>
<DOC>
<DOCNO> 121960 </DOCNO>
The Tail of the HI Mass Function


  The contribution of extragalactic objects with HI masses below $10^8 M_\odot$
to the HI mass function remains uncertain. Several aspects of the detection of
low-mass sources in HI surveys are not always considered, and as a result
different analysis techniques yield widely different estimates for their number
density. It is suggested at one extreme that the number density of galaxies
follows a shallow Schechter power-law slope, and at the other extreme that it
follows a steep faint-end rise like that found for field optical sources. Here
we examine a variety of selection effects, issues of completeness, and
consequences of LSS. We derive results for the large Arecibo Dual Beam Survey
which indicate that the field mass function does rise steeply, while within the
Virgo Cluster environs, the slope appears to be much shallower. Dependence on
the local density of galaxies may partially explain differences between
surveys.

</DOC>
<DOC>
<DOCNO> 178638 </DOCNO>
Effective range function below threshold


  We demonstrate that the kernel of the Lippmann-Schwinger equation, associated
with interactions consisting of a sum of the Coulomb plus a short range nuclear
potential, below threshold becomes degenerate. Taking advantage of this fact,
we present a simple method of calculating the effective range function for
negative energies. This may be useful in practice since the effective range
expansion extrapolated to threshold allows to extract low-energy scattering
parameters: the Coulomb-modified scattering length and the effective range.

</DOC>
<DOC>
<DOCNO> 118477 </DOCNO>
[OII]3727 Emission from the Companion to the Quasar BR 1202-0725 at


  Results of a narrow-band imaging for the redshifted [OII]3727 emission around
a quasar at z=4.7 obtained with the Subaru telescope and CISCO (a Cassegrain
near infrared camera) are presented. A significant emission line is detected in
the narrow-band H_2 (v=1-0 S(1)) filter at a location 2.4" northwest from the
quasar, where the presence of a companion has been reported in Lyman alpha
emission and the rest-frame UV continuum. We identify this line as [OII]3727
emission and confirm that the source really is a companion at z=4.7. The
[OII]3727 flux from the companion is estimated to be 2.5 x 10^{-17} erg s^{-1}
cm^{-2}. If the companion is a star forming object, the inferred star formation
rate is as high as 45-230 M_{solar} yr^{-1} even without assuming the
extinction correction. This value is higher than those derived from the Lyman
alpha emission or from the UV continuum. Thus, provided that the difference is
caused by dust extinction, the extinction corrected star formation rate is
calculated to be 45 to 2300 M_{solar} yr^{-1} depending on the assuming
extinction curves.

</DOC>
<DOC>
<DOCNO> 118818 </DOCNO>
Studies of multiple stellar systems - III. Modulation of orbital


  The triple-lined spectroscopic triple system HD 109648 has one of the
shortest periods known for the outer orbit in a late-type triple, 120.5 days,
and the ratio between the periods of the outer and inner orbits is small, 22:1.
With such extreme values, this system should show orbital element variations
over a timescale of about a decade. We have monitored the radial velocities of
HD 109648 with the CfA Digital Speedometers for eight years, and have found
evidence for modulation of some orbital elements. While we see no definite
evidence for modulation of the inner binary eccentricity, we clearly observe
variations in the inner and outer longitudes of periastron, as well as in the
radial velocity amplitudes of the three components. The observational results,
combined with numerical simulations, allow us to put constraints on the
orientation of the orbits.

</DOC>
<DOC>
<DOCNO> 152199 </DOCNO>
One-loop four-point function in noncommutative {\cal N}=4 Yang-Mills


  We compute the one-loop four-point function in {\cal N}=4 supersymmetric
Yang-Mills theory with gauge group U(N). We perform the calculation in {\cal
N}=1 superspace using the background field method and obtain the complete
off-shell contributions to the effective action from planar and non planar
supergraphs. In the low-energy approximation the result simplifies and we can
study its properties under gauge transformations. It appears that the nonplanar
contributions do not maintain the gauge invariance of the classical action.

</DOC>
<DOC>
<DOCNO> 102067 </DOCNO>
On polytopes simple in edges


  We investigate some combinatorial properties of convex polytopes simple in
edges. For polytopes whose nonsimple vertices are located sufficiently far one
from another, we prove an analog of the Hard Lefschetz theorem. It implies
Stanley's conjecture for such polytopes.

</DOC>
<DOC>
<DOCNO> 170491 </DOCNO>
Entanglement transformation at dielectric four-port devices


  Quantum communication schemes widely use dielectric four-port devices as
basic elements for constructing optical quantum channels. Since for causality
reasons the permittivity is necessarily a complex function of frequency,
dielectrics are typical examples of noisy quantum channels in which quantum
coherence will not be preserved. Basing on quantization of the phenomenological
electrodynamics, we construct the transformation relating the output quantum
state to the input quantum state without placing frequency restrictions.
Knowledge of the full transformed quantum state enables us to compute the
entanglement contained in the output quantum state. We apply the formalism to
some typical examples in quantum communication.

</DOC>
<DOC>
<DOCNO> 99389 </DOCNO>
Some results on rational surfaces and Fano varieties


  The goal of this article is to study the equations and syzygies of embeddings
of rational surfaces and certain Fano varieties. Given a rational surface X and
an ample and base-point-free line bundle L on X, we give an optimal numerical
criterion for L to satisfy property Np. This criterion turns out to be a
characterization of property Np if X is anticanonical. We also prove syzygy
results for adjunction bundles and a Reider type theorem for higher syzygies.
  For certain Fano varieties we also prove results on very ampleness and higher
syzygies.

</DOC>
<DOC>
<DOCNO> 170187 </DOCNO>
Entropic uncertainty relation for power-law wave packets


  For the power-law quantum wave packet in configuration space, the variance of
the position observable may be divergent, and, accordingly, the Heisenberg-type
formulation of the uncertainty principle becomes weak. In contrast to such a
situation, the information-entropic formulation involves only finite
quantities, thus displaying its superiority over the Heisenberg-type relation.
We attempt to clarify here just how the total amount of entropic uncertainty
converges to its lower bound in the limit of a large value for the exponent of
the power-law wave packet.

</DOC>
<DOC>
<DOCNO> 178404 </DOCNO>
Proton decay of high-lying states in odd nuclei


  In the framework of the quasiparticle-phonon model, we study the
non-statistical proton decay of excited states in odd nuclei towards low-lying
collective states. Partial cross sections and branching ratios for the proton
decay of the high angular momentum states in $^{41}$Sc, $^{59}$Cu and $^{91}$Nb
%{\it excited by means of the ($^{7}$Li,$^{6}$He) reaction} are evaluated. The
calculated branching ratios predict strong direct proton decays to the
low-lying vibrational states in $^{41}$Sc and $^{91}$Nb. A general agreement
with existing experimental data is found.

</DOC>
<DOC>
<DOCNO> 119662 </DOCNO>
Relativistic Conic Beams and Spatial Distribution of Gamma-Ray Bursts


  We study the statistics of gamma-ray bursts, assuming that gamma-ray bursts
are cosmological and they are beamed in the form of a conical jet with a large
bulk Lorentz factor $\sim 100$. In such a conic beam, the relativistic ejecta
may have a spatial variation in the bulk Lorentz factor and the density
distribution of gamma-ray emitting jet material. An apparent luminosity
function arises because the axis of the cone is randomly oriented with respect
to the observer's line of sight. The width and the shape of the luminosity
function are determined by the ratio of the beam opening angle of the conical
jet to the inverse of the bulk Lorentz factor, when the bulk Lorentz factor and
the jet material density is uniform on the photon emitting jet surface. We
calculate effects of spatial variation of the Lorentz factor and the spatial
density fluctuations within the cone on the luminosity function and the
statistics of gamma-ray bursts. In particular, we focus on the redshift
distribution of the observed gamma-ray bursts. The maximum distance to and the
average redshift of the gamma-ray bursts are strongly affected by the
beaming-induced luminosity function. The bursts with the angle-dependent
Lorentz factor which peaks at the center of the cone have substantially higher
average gamma-ray burst redshifts. When both the jet material density and the
Lorentz factor are inhomogeneous in the conical beam, the average redshift of
the bursts could be 5 times higher than that of the case in which relativistic
jet is completely homogeneous and structureless. Even the simplest models for
the gamma-ray burst jets and their apparent luminosity distributions have a
significant effect on the redshift distribution of the gamma-ray bursts.

</DOC>
<DOC>
<DOCNO> 13017 </DOCNO>
Anomalous Scaling of the SO(8) Symmetric Phases in the Two-Leg Ladder


  We carry out a complete analytical stability study for the SO(8) symmetric
phases in the weakly-interacting two-leg ladder. It is shown that the SO(8)
symmetry is robust under generic perturbations. Since there are no fixed points
in the one-loop renormalization group equations, the conventional
classification of relevant and irrelevant perturbations fails in this case. A
new classification is defined and explained in detail. It leads to the
anomalous scaling in the ratios of excitation gaps and an universal exponent
1/3 is extracted. This new method is also applied to the well studied 2D Ising
model and similar exponent is calculated.

</DOC>
<DOC>
<DOCNO> 169983 </DOCNO>
Linking Classical and Quantum Key Agreement: Is There ``Bound


  After carrying out a protocol for quantum key agreement over a noisy quantum
channel, the parties Alice and Bob must process the raw key in order to end up
with identical keys about which the adversary has virtually no information. In
principle, both classical and quantum protocols can be used for this
processing. It is a natural question which type of protocols is more powerful.
We prove for general states but under the assumption of incoherent
eavesdropping that Alice and Bob share some so-called intrinsic information in
their classical random variables, resulting from optimal measurements, if and
only if the parties' quantum systems are entangled. In addition, we provide
evidence that the potentials of classical and of quantum protocols are equal in
every situation. Consequently, many techniques and results from quantum
information theory directly apply to problems in classical information theory,
and vice versa. For instance, it was previously believed that two parties can
carry out unconditionally secure key agreement as long as they share some
intrinsic information in the adversary's view. The analysis of this purely
classical problem from the quantum information-theoretic viewpoint shows that
this is true in the binary case, but false in general. More explicitly, bound
entanglement, i.e., entanglement that cannot be purified by any quantum
protocol, has a classical counterpart. This ``bound intrinsic information''
cannot be distilled to a secret key by any classical protocol. As another
application we propose a measure for entanglement based on classical
information-theoretic quantities.

</DOC>
<DOC>
<DOCNO> 83441 </DOCNO>
Efficient Quantum Algorithms for Shifted Quadratic Character Problems


  We introduce the Shifted Legendre Symbol Problem and some variants along with
efficient quantum algorithms to solve them. The problems and their algorithms
are different from previous work on quantum computation in that they do not
appear to fit into the framework of the Hidden Subgroup Problem. The classical
complexity of the problem is unknown despite the various results on the
irregularity of Legendre Sequences.

</DOC>
<DOC>
<DOCNO> 71658 </DOCNO>
Search for new physics via CP violation in $B_{d,s} \to l^+ l^-


  It is shown that in the approximation of $|\frac{q}{p}|$=1 the CP violation
in $B^0_{d,s} \to l^+ l^-$ decays vanishes in SM. In a 2HDM with CP violating
phases and MSSM the CP asymmetries depend on the parameters of models and can
be as large as 40% for $B^0_d$ and 3% for $B^0_s$. An observation of CP
asymmetry in the decays would unambiguously signal the existence of new
physics.

</DOC>
<DOC>
<DOCNO> 170026 </DOCNO>
Cooling of a small sample of Bose atoms with accidental degeneracy


  A system of bosons in a harmonic trap is cooled via their interactions with a
thermal reservoir. We derive the master equation that governs the evolution of
the system and may describe diverse physical situations: laser cooling,
symphatetic cooling, etc. We investigate in detail the dynamics of the gas in
the Lamb-Dicke limit, whereby the size of the trap is small in comparison to
the de Broglie wavelength of the reservoir quanta. In this case, the dynamics
is characterized by two time scales. First, an equilibrium is reached on a fast
time scale within the degenerated subspaces of the system. Then, an equilibrium
between these subspaces is reached on a slow time scale.

</DOC>
<DOC>
<DOCNO> 117632 </DOCNO>
MACS: The evolution and properties of massive clusters of galaxies


  We present first results from the MAssive Cluster Survey (MACS), a new
large-scale X-ray survey designed to find and characterize very massive,
distant clusters of galaxies. Based on X-ray detections in the ROSAT All-Sky
Survey, MACS aims to compile a sample of more than 200 X-ray luminous clusters
at z>0.3, about 50 times the number of EMSS clusters in the same redshift and
luminosity range. The MACS sample is uniquely suited to investigate cluster
evolution at redshifts and luminosities poorly sampled by all existing surveys.
  At the time of writing the MACS sample comprises 41 clusters with measured
redshifts of 0.3<z<0.56 and X-ray luminosities in excess of 6 10^44 erg/s
(0.1-2.4 keV). This early sample is thus already twice as large as the high-z,
high-luminosity subsets of the EMSS, BCS, and REFLEX cluster samples taken
together. An additional 85 MACS clusters with photometric redshifts z>0.3 are
scheduled for spectroscopic observation.
  From a preliminary analysis of a statistically well defined subsample of the
25 X-ray brightest MACS clusters we conclude tentatively that negative
evolution is not significant at the highest X-ray luminosities (Lx>10^45 erg/s)
out to redshifts of z~0.4. Our findings thus extend the no-evolution result
obtained by many serendipitous ROSAT cluster surveys at lower luminosities.

</DOC>
<DOC>
<DOCNO> 67986 </DOCNO>
Introduction to Neutrinos


  We discuss current theoretical and experimental issues associated with the
recent SuperKamiokande discovery. We survey theoretical models for predictings
the new Standard Model parameters needed to explain this discovery, and point
out how quark-lepton symmetries, either in the framework of Grand Unification,
or of string theories, can be used to determine them.

</DOC>
<DOC>
<DOCNO> 99356 </DOCNO>
On representation of the P-Q pair solution at the singular point


  The compatible expansion in series of solutions of both the equations of P-Q
pair at neighborhood of the singular point is obtained in closed form for
regular and irregular singularities. The conservation laws of the system of
ordinary differential equations to arise from the compatibility condition of
the P-Q pair are derived.

</DOC>
<DOC>
<DOCNO> 101725 </DOCNO>
On bifurcation points of the stationary Vlasov-Maxwell system with


  The theorem on the existence of bifurcation points of the stationary
solutions for the Vlasov-Maxwell system with bifurcation direction is proved.

</DOC>
<DOC>
<DOCNO> 39955 </DOCNO>
Model Independent Extra-dimension signatures with ATLAS


  The generic missing transverse energy signals at LHC for theories having
large extra dimensions are discussed. Final states of jets plus missing energy
and photons plus missing energy are simulated in the ATLAS detector. The
discovery limit of LHC and the methods to determine the parameters of the
underlying model are discussed.

</DOC>
<DOC>
<DOCNO> 100705 </DOCNO>
Double Sections and Dominating Maps


  As is well-known, there exist nonconstant holomorphic maps from the plane
into the Riemann sphere $\PP^1$ minus two points, the simplest example of which
is an explicit realization of the uniformization map given by applying the
exponential map and then composing with a Mobius transformation taking 0 and
$\infty$ to the two given punctures. Likewise, we can map the plane into the
sphere minus one point by simply applying directly a Mobius transformation
taking $\infty$ to this puncture.
  In this paper we prove two parametrized versions of this uniformization
result using different methods. We first present a slightly easier version
using complex analysis, which allows us to construct the uniformizing maps more
or less explicitly in terms of the initial coordinates given. Then we give the
more general and coordinate invariant version, which we prove by extending
Kodaira's theory of the Jacobian fibration to a family of singular curves
constructed via algebraic geometry.
  Finally, using the results obtained with the Jacobian fibration, we obtain
two equivalent conditions for an complex surface nonhyperbolically fibered over
a complex curve to be holomorphically dominable by $\CC^2$. In theorem
\ref{thm:surf} we show that this dominability is equivalent to the apparently
weaker condition of the existence of a Zariski dense image of $\CC$ and
equivalent to the quasiprojectivity of the base curve together with the
nonnegativity of the orbifold Euler characteristic.

</DOC>
<DOC>
<DOCNO> 83179 </DOCNO>
Reliable Cellular Automata with Self-Organization


  In a probabilistic cellular automaton in which all local transitions have
positive probability, the problem of keeping a bit of information indefinitely
is nontrivial, even in an infinite automaton. Still, there is a solution in 2
dimensions, and this solution can be used to construct a simple 3-dimensional
discrete-time universal fault-tolerant cellular automaton. This technique does
not help much to solve the following problems: remembering a bit of information
in 1 dimension; computing in dimensions lower than 3; computing in any
dimension with non-synchronized transitions.
  Our more complex technique organizes the cells in blocks that perform a
reliable simulation of a second (generalized) cellular automaton. The cells of
the latter automaton are also organized in blocks, simulating even more
reliably a third automaton, etc. Since all this (a possibly infinite hierarchy)
is organized in ``software'', it must be under repair all the time from damage
caused by errors. A large part of the problem is essentially self-stabilization
recovering from a mess of arbitrary size and content. The present paper
constructs an asynchronous one-dimensional fault-tolerant cellular automaton,
with the further feature of ``self-organization''. The latter means that unless
a large amount of input information must be given, the initial configuration
can be chosen homogeneous.

</DOC>
<DOC>
<DOCNO> 69737 </DOCNO>
Search for solar Kaluza-Klein axions in theories of low-scale quantum


  We explore the physics potential of a terrestrial detector for observing
axionic Kaluza-Klein excitations coming from the Sun within the context of
higher-dimensional theories of low-scale quantum gravity. In these theories,
the heavier Kaluza-Klein axions are relatively short-lived and may be detected
by a coincidental triggering of their two-photon decay mode. Because of the
expected high multiplicity of the solar axionic excitations, we find
experimental sensitivity to a fundamental Peccei-Quinn axion mass up to
$10^{-2}$ eV (corresponding to an effective axion-photon coupling $g_{a\gamma
\gamma} \approx 2.\times 10^{-12}$ GeV$^{-1}$) in theories with 2 extra
dimensions and a fundamental quantum-gravity scale $M_{\rm F}$ of order 100
TeV, and up to $3.\times 10^{-3}$ eV (corresponding to $g_{a\gamma \gamma}
\approx 6.\times 10^{-13}$ GeV$^{-1}$) in theories with 3 extra dimensions and
$M_{\rm F}=1$ TeV. For comparison, based on recent data obtained from lowest
level underground experiments, we derive the experimental limits: $g_{a \gamma
\gamma} \stackrel{<}{{}_\sim} 2.5\times 10^{-11}$ GeV$^{-1}$ and $g_{a \gamma
\gamma} \stackrel{<}{{}_\sim} 1.2\times 10^{-11}$ GeV$^{-1}$ in the
aforementioned theories with 2 and 3 large compact dimensions, respectively.

</DOC>
<DOC>
<DOCNO> 71223 </DOCNO>
(Quasi)Localized Gauge Field on a Brane: Dissipating Cosmic Radiation to


  We propose a mechanism ensuring (quasi)localization of massless gauge fields
on a brane. The mechanism does not rely on BPS properties of the brane and can
be realized in any theory where charged particles are confined to the
world-volume. The localized matter fluctuations induce a gauge kinetic term on
the brane. At short distances the resulting propagator for the gauge field is
{\it identical} to the four-dimensional propagator. The gauge theory on the
brane is effectively four-dimensional at short distances; it becomes
higher-dimensional on very large (cosmic) scales. The brane-bulk system
exhibits the phenomenon of ``infrared transparency''. As a result, only very
low frequency modes can escape into extra dimensions. In this framework the
large wavelength cosmic radiation can dissipate in extra space at a rate that
may be observable, in principle. We briefly discuss some astrophysical
consequences of this scenario.
  The same mechanism of localization of gauge fields may work in Kaplan's
framework for domain wall chiral fermions on lattices.

</DOC>
<DOC>
<DOCNO> 100970 </DOCNO>
Leibniz Algebras, Courant Algebroids, and Multiplications on Reductive


  We show that the skew-symmetrized product on every Leibniz algebra E can be
realized on a reductive complement to a subalgebra in a Lie algebra. As a
consequence, we construct a nonassociative multiplication on E which, when E is
a Lie algebra, is derived from the integrated adjoint representation. We apply
this construction to realize the bracket operations on the sections of Courant
algebroids and on the ``omni-Lie algebras'' recently introduced by the second
author.

</DOC>
<DOC>
<DOCNO> 84864 </DOCNO>
R-modes of neutron stars with a solid crust


  We investigate the properties of $r$-mode oscillations of a slowly rotating
neutron star with a solid crust, by taking account of the effects of the
Coriolis force. For the modal analysis we employ three-component neutron star
models that are composed of a fluid core, a solid crust and a surface fluid
ocean. For the three-component models, we find that there exist two kinds of
$r$-modes, that is, those confined in the surface fluid ocean and those
confined in the fluid core, which are most important for the $r$-mode
instability. The $r$-modes do not have any appreciable amplitudes in the solid
crust if rotation rate of the star is sufficiently small. We find that the core
$r$-modes are strongly affected by mode coupling with the crustal torsional
(toroidal) modes and lose their simple properties of the eigenfunction and
eigenfrequency as functions of the angular rotation velocity $\Omega$. This
indicates that the extrapolation formula, which is obtained in the limit of
$\Omega\to 0$, cannot be used to examine the $r$-mode instability of rapidly
rotating neutron stars with a solid crust unless the effects of mode coupling
with the crustal torsional modes are correctly taken into account.

</DOC>
<DOC>
<DOCNO> 11833 </DOCNO>
Velocity correlations and the structure of nonequilibrium hard core


  A model for the pair distribution function of nonequilibrium hard-core fluids
is proposed based on a model for the effect of velocity correlations on the
structure. Good agreement is found with molecular dynamics simulations of
granular fluids and of sheared elastic hard spheres. It is argued that the
incorporation of velocity correlations are crucial to correctly modeling atomic
scale structure in nonequilibrium fluids.

</DOC>
<DOC>
<DOCNO> 13618 </DOCNO>
Rotating fermions in two dimensions: Thomas Fermi approach


  Properties of confined mesoscopic systems have been extensively studied
numerically over recent years. We discuss an analytical approach to the study
of finite rotating fermionic systems in two dimension. We first construct the
energy functional for a finite fermionic system within the Thomas-Fermi
approximation in two dimensions. We show that for specific interactions the
problem may be exactly solved. We derive analytical expressions for the
density, the critical size as well as the ground state energy of such systems
in a given angular momentum sector.

</DOC>
<DOC>
<DOCNO> 117412 </DOCNO>
Evolution of Cluster Galaxies in Hierarchical Clustering Universes


  Using cosmological N-body simulations of critical (SCDM) and open ($\Omega =
0.3$, OCDM) cold dark matter models, we investigate evolution of cluster
galaxies. From our numerical simulation, we construct merging history trees of
the galaxies. By following their merging history, we show major merger
fractions of the galaxies in cluster forming regions is roughly proportional to
(1+z)^{4.5} at low redshifts (z < 2) and has a steep peak at $z \simeq 2.5$ and
$z \simeq 3$ in SCDM and OCDM, respectively. We also show that the cluster
galaxies are affected by tidal interaction after the clusters formed. Because
the formation redshift of the cluster in SCDM, z_{form} = 0.15, is much more
recent than that of the cluster in OCDM, z_{form} = 1.6, the cluster galaxies
in SCDM show more rapid evolution by tidal interactions from z = 0.5 than those
in OCDM.

</DOC>
<DOC>
<DOCNO> 119908 </DOCNO>
Simulations of Foreground Effects for CMB Polarization


  We use a simple model to investigate the effect of polarized Galactic
foreground emission on the ability of planned CMB missions to detect and model
CMB polarization. Emission from likely polarized sources (synchrotron and
spinning dust) would dominate the polarization of the microwave sky at
frequencies below 90 GHz if known Galactic foregrounds are at least 10%
polarized at high latitude (|b| > 30 deg). Maps of polarization at frequencies
below 90 GHz will likely require correction for foreground emission to enable
statistical analysis of the individual Stokes Q or U components. The
temperature-polarization cross-correlation is less affected by foreground
emission, even if the foreground polarization is highly correlated with the
foreground intensity. Polarized foregrounds, even if uncorrected, do not
dominate the uncertainty in the temperature-polarization cross-correlation for
instrument noise levels typical of the MAP experiment. Methods which remove
galactic signals at the cost of signal to noise ratio should carefully balance
the value of rejecting faint foregrounds with the cost of increased instrument
noise.

</DOC>
<DOC>
<DOCNO> 39782 </DOCNO>
Dynamics of the decay eta->3pi0


  The parameter $ \alpha = -0.005 \pm 0.007 (stat) \pm 0.004 (syst)$ describing
the density of events within the $ \eta \to 3\pi^0 $ Dalitz plot has been
measured using data from Brookhaven experiment E852. The result is compared to
previous values and theoretical predictions.

</DOC>
<DOC>
<DOCNO> 118726 </DOCNO>
Chandra, GLAST, and the Galactic Center


  Two-temperature spherical accretion flows produce $\approx 100$ Mev
gamma-rays from the decay of neutral pions created in proton-proton collisions
close to the black hole; they also produce $\sim 10$ keV X-rays by
bremsstrahlung emission at large radii. The gamma-ray to X-ray luminosity ratio
is nearly independent of black hole mass and accretion rate. It does depend
sensitively on the radial density profile of the accretion flow through the
parameter a, where $n \propto r^{-a}$. For the canonical Bondi value of a =
3/2, the gamma-ray to X-ray luminosity ratio is $\approx 30$. We interpret a
recent Chandra detection coincident with the massive black hole at the Galactic
Center as being thermal bremsstrahlung emission from the accretion flow. With
this normalization, the expected gamma-ray luminosity is $\approx 10^{35}$ ergs
s$^{-1}$ if a = 3/2. This is nearly two orders of magnitude above the detection
threshold of the GLAST telescope. For $a \approx 1/2$, however, (a value
suggested by recent theoretical arguments), the expected gamma-ray luminosity
is only $\approx 10^{29}$ ergs s$^{-1}$; GLAST should therefore provide an
important probe of the true accretion rate and radial density profile of the
accretion flow onto Sgr A*.

</DOC>
<DOC>
<DOCNO> 118649 </DOCNO>
Convective-Dynamical Instability in Radiation-Supported Accretion Disks


  We study radiation-hydrodynamical normal modes of radiation-supported
accretion disks in the WKB limit. It has long been known that in the large
optical depth limit the standard equilibrium is unstable to convection. We
study how the growth rate depends on location within the disk, optical depth,
disk rotation, and the way in which the local dissipation rate depends on
density and pressure. The greatest growth rates are found near the disk
surface. Rotation stabilizes vertical wavevectors, so that growing modes tend
to have nearly-horizontal wavevectors. Over the likely range of optical depths,
the linear growth rate for convective instability has only a weak dependence on
disk opacity. Perturbations to the dissipation have little effect on convective
mode growth rates, but can cause growth of radiation sound waves.

</DOC>
<DOC>
<DOCNO> 102313 </DOCNO>
Exotic structures and adjunction inequality


  We reprove and strengthen some old difficult theorems of 4-manifolds by the
aid of recently discovered modern tools, which involve contact structures on
3-manifolds, compact Stein domains, etc.

</DOC>
<DOC>
<DOCNO> 123294 </DOCNO>
The 0.1-200 keV spectrum of the blazar PKS 2005-489 during an active


  The bright BL Lac object PKS 2005-489 was observed by BeppoSAX on November
1-2, 1998, following an active X-ray state detected by RossiXTE. The source,
detected between 0.1 and 200 keV, was in a very high state with a continuum
well fitted by a steepening spectrum due to synchrotron emission only. Our
X-ray spectrum is the flattest ever observed for this source. The different
X-ray spectral slopes and fluxes, as measured by various satellites, are
consistent with relatively little changes of the peak frequency of the
synchrotron emission, always located below 10^{17} Hz. We discuss these results
in the framework of synchrotron self-Compton models. We found that for the
BeppoSAX observation, the synchrotron peak frequency is between 10^{15} and
2.5x10^{16} Hz, depending on the model assumptions.

</DOC>
<DOC>
<DOCNO> 85320 </DOCNO>
Possible Extensions of the 4-d Schwarzschild Horizon in the Brane World


  We show that, in the absence of matter in the bulk, the Einstein equations
and the Gauss-normal form of the metric place stringent restrictions on the
form of the event horizon in a brane world. As a consequence, the off-brane
extension of the standard 4-D Schwarzschild horizon in the Randall-Sundrum
$AdS_5$ spacetime, as it is viewed from the brane can only be of a tubular
shape, instead of a pancake shape. When it is viewed from the $AdS_5$ horizon,
such a tubular horizon is absent.

</DOC>
<DOC>
<DOCNO> 116344 </DOCNO>
X-Ray Kinematography of Temperature-Jump Relaxation Probes the Elastic


  The response kinetics of liquid crystalline phosphatidylcholine bilayer
stacks to rapid, IR-laser induced temperature jumps has been studied by
millisecond time-resolved x-ray diffraction. The system reacts on the fast
temperature change by a discrete bilayer compression normal to its surface and
a lateral bilayer expansion. Since water cannot diffuse from the excess phase
into the interbilayer water region within the 2 ms duration of the laser pulse,
the water layer has to follow the bilayer expansion, by an anomalous thinning.
Structural analysis of a 20 ms diffraction pattern from the intermediate phase
indicates that the bilayer thickness remains within the limits of isothermal
equilibrium values. Both, the intermediate structure and its relaxation into
the original equilibrium L_(alpha)-phase, depend on the visco-elastic
properties of the bilayer/water system. We present an analysis of the
relaxation process by an overdamped one-dimensional oscillation model revealing
the concepts of Hooke's law for phospholipid bilayers on a supramolecular
basis. The results yield a constant bilayer repulsion and viscosity within
Hooke's regime suggesting that the hydrocarbon chains act as a buffer for the
supplied thermal energy. The bilayer compression is a function of the initial
temperature and the temperature amplitude, but is independent of the chain
length.

</DOC>
<DOC>
<DOCNO> 11537 </DOCNO>
On the Dynamics of the Evolution of the HIV Infection


  We use a cellular automata model to study the evolution of HIV infection and
the onset of AIDS. The model takes into account the global features of the
immune response to any pathogen, the fast mutation rate of the HIV and a fair
amount of spatial localization. Our results reproduce quite well the
three-phase pattern observed in T cell and virus counts of infected patients,
namely, the primary response, the clinical latency period and the onset of
AIDS. We have also found that the infected cells may organize themselves into
special spatial structures since the primary infection, leading to a decrease
on the concentration of uninfected cells. Our results suggest that these cell
aggregations, which can be associated to syncytia, leads to AIDS.

</DOC>
<DOC>
<DOCNO> 120673 </DOCNO>
Mapping the Galactic Halo II: Photometric Survey


  We present imaging results from a high Galactic latitude survey designed to
examine the structure of the Galactic halo. The objective of the survey is to
identify candidate halo stars which can be observed spectroscopically to obtain
radial velocities and confirm halo membership. The Washington filter system is
used for its ability to distinguish between dwarfs and giants, as well as
provide a metallicity indicator. Our most successful imaging run used the BTC
camera on the CTIO 4m telescope in April 1999. Photometric conditions during
these observations provided superb photometry, with average errors for a star
at $M=18.5$ of 0.009, 0.008, 0.011, and 0.009 for $C$, $M$, $DDO51$, and $T2$
respectively. These data are available with the electronic version of this
paper, as well as through ADC (http://adc.gsfc.nasa.gov/). We use these data as
a template to describe the details of our photometric reduction process. It is
designed to perform CCD reductions and stellar photometry automatically during
the observation run without the aid of external packages, such as IRAF and IDL.
We describe necessary deviations from this procedure for other instruments used
in the survey up to June 2000. Preliminary results from spectroscopic
observations indicate a 97% efficiency in eliminating normal dwarfs from halo
giant candidates for $M<18.5$. Unfortunately, low-metallicity subdwarfs cannot
be photometrically distinguished from giants using the Washington filters.
These major contaminates unavoidably reduced the overall giant identification
efficiency to 66% for $M<18.5$. Our improved knowledge of these stars will
increase this efficiency for future spectroscopic observations.

</DOC>
<DOC>
<DOCNO> 170270 </DOCNO>
A realistic interpretation of the density matrix II: The


  The interpretation proposed in quant-ph/9812011 is extended to the general
case of a non-relativistic particle moving in an arbitrary external potential.
It is shown that, even in this general case, "particle" solutions exist which
do not spread out with time, and remain well localized around their center of
mass; it is postulated that these are the only solutions which represent
individual physical particles. As a consequence two basic principles of
standard QM, namely the superposition principle and the wave-function collapse,
are shown to have no ontological meaning. Three simple applications of our
approach are then examined: the free particle, the linear harmonic oscillator
and the delta barrier potential; the corresponding "particle" solutions are
explicitly shown. Finally, it is argued that the persisting confusion about the
meaning of the wave-function (does it represent an individual particle or a
statistical ensemble?) calls for a non-linear extension of the Schroedinger
equation.

</DOC>
<DOC>
<DOCNO> 99544 </DOCNO>
A Subadditivity Property of Multiplier Ideals


  Given an effective Q-divisor D on a smooth complex variety, one can associate
to D its multiplier ideal sheaf J(D), which measures in a somewhat subtle way
the singularities of D. Because of their strong vanishing properties, these
ideals have come to play an increasingly important role in higher dimensional
geometry. We prove that for two effective Q-divisors D and E, one has the
"subadditivity" relation: J(D + E) \subseteq J(D) . J(E) . (We also establish
several natural variants, including the analogous statement for the analytic
multiplier ideals associated to plurisubharmonic functions.) As an application,
we give a new proof of a theorem of Fujita concerning the volume of a big
linear series on a projective variety. The first section of the paper contains
an overview of the construction and basic properties of multiplier ideals from
an algebro-geometric perspective, as well as a discussion of the relation
between some asymptotic algebraic constructions and their analytic
counterparts.

</DOC>
<DOC>
<DOCNO> 40460 </DOCNO>
Some comments on the missing charm puzzle


  In this talk we summarize the status of theoretical predictions for the
average number of charm quarks in a B-hadron decay.

</DOC>
<DOC>
<DOCNO> 70521 </DOCNO>
Lepton asymmetry creation in the Early Universe


  Oscillations of active to sterile neutrinos with a small mixing angle sin 2
\theta < 10^{-2} could generate a large lepton asymmetry in the Early Universe.
The final order of magnitude of the lepton asymmetry \eta is mainly determined
by its growth in the last stage of evolution, the so called power-law regime.
There exist two contradictory results in the literature, \eta \propto T^{-1}
and \eta \propto T^{-4}, where T is the background medium temperature. In the
first case, the lepton asymmetry does not exceed values of 10^{-4} for |\delta
m^2| < 1 eV^2, while in the second case it can become larger than 10^{-1}. In
this work we analytically investigate the case \eta \propto T^{-1}, using a new
approach to solve the kinetic equations. We find that the power-law solution
\eta \propto T^{-1} is not self-consistent. Instead, we find the power law \eta
\propto T^{-11/3} to be a good approximation, which leads to a large final
asymmetry.

</DOC>
<DOC>
<DOCNO> 10563 </DOCNO>
Molecular Weight Dependent Kernels in Generalized Mixing Rules


  In this paper, a model is proposed for the kernel in the generalized mixing
rule recently formulated by Anderssen and Mead (1998). In order to derive such
a model, it is necessary to take account of the rheological significance of the
kernel in terms of the relaxation behaviour of the individual polymers
involved. This leads naturally to consider a way how additional physical
effects, which depend on the molecular weight distribution, can be included in
the mixing rule. The advantage of this approach is that, without changing the
generality derived by Anderssen and Mead (1998), the choice of the model
proposed here for the kernel guarantees the enhanced physical and rheological
significance of their mixing rule.

</DOC>
<DOC>
<DOCNO> 151641 </DOCNO>
A Note on Background Independence in Noncommutative Gauge Theories,


  Using the construction of D-branes with nonzero $B$ field in the matrix model
we give a physical interpretation of the known background independence in gauge
theories on a noncommutative space. The background independent variables are
identified as the degrees of freedom of the underlying matrix model. This
clarifies and extends some recent results about the end point of tachyon
condensation in D-branes with a $B$ field. We also explain the freedom in the
description which is parametrized by a two form $\Phi$ from the points of view
of the noncommutative geometry on the worldvolume of the branes, and of the
first quantized string theory.

</DOC>
<DOC>
<DOCNO> 70226 </DOCNO>
Polarized J/psi from chi_{cJ} and psi' Decays at the Tevatron


  We calculate the partonic cross sections for the hadroproduction of polarized
chi_{cJ} mesons using the factorization formalism of nonrelativistic QCD. We
also describe how the polarization is passed on to the J/psi mesons in the
radiative feed-down chi_{cJ} -> J/psi + gamma and in the double-cascade decays
of psi' mesons via chi_{cJ} intermediate states. These represent the missing
ingredients needed to predict the polarization of prompt J/psi mesons at the
Fermilab Tevatron.

</DOC>
<DOC>
<DOCNO> 117938 </DOCNO>
Properties of Proto--Planetary Nebulae


  This review describes some general properites of proto-planetary nebulae with
particular emphasis on the recent work of morpholgical studies. The weight of
observational evidence shows that proto-planetary nebulae (PPNe) are most
certainly axisymmetric like planetary nebulae. Recent work suggests two
subclasses of PPNe optical morphology, DUst-Prominent Longitudinally-EXtended
(DUPLEX) and Star-Obvious Low-level Elongated (SOLE). Radiative transfer models
of an example DUPLEX PPN and SOLE PPN, presented here, support the
interpretation that DUPLEX and SOLE are two physically distinct types of PPNe.
The DUPLEX PPNe and SOLE PPNe may well be the precursors to bipolar and
elliptical PNe, respectively.

</DOC>
<DOC>
<DOCNO> 85201 </DOCNO>
The doomsday argument and the number of possible observers


  If the human race comes to an end relatively shortly, then we have been born
at a fairly typical time in history of humanity. On the other hand, if humanity
lasts for much longer and trillions of people eventually exist, then we have
been born in the first surprisingly tiny fraction of all people. According to
the Doomsday Argument of Carter, Leslie, Gott, and Nielsen, this means that the
chance of a disaster which would obliterate humanity is much larger than
usually thought. Here I argue that treating possible observers in the same way
as those who actually exist avoids this conclusion. Under this treatment, it is
more likely to exist at all in a race which is long-lived, as originally
discussed by Dieks, and this cancels the Doomsday Argument, so that the chance
of a disaster is only what one would ordinarily estimate. Treating possible and
actual observers alike also allows sensible anthropic predictions from quantum
cosmology, which would otherwise depend on one's interpretation of quantum
mechanics.

</DOC>
<DOC>
<DOCNO> 116900 </DOCNO>
High Current Beam Dynamics in an Ess SC Linac


  Three alternative designs of the European Spallation Source (ESS) high energy
linac are described. The most promising ones are either a normalconducting (nc)
coupled cavity linac (CCL) up tofinal energy or a change at 407 MeV to only one
group of 6 cell superconducting (sc) elliptical cavities.
  Fully 3d Monte Carlo simulations are presented for both options, optimized
for reduced halo formation at the linac end. For the error free matched case,
especially the halo formation in the longitudinal plane is more pronounced for
the hybrid solution with its superconducting cavities, caused by the
unavoidable phase slippage, but still quite well acceptable for loss free ring
injection. Simulations however for a 30% mismatched dense core, surrounded in
addition by 1.5% halo particles are showing few particles with very large
amplitudes even in real space. This case represents halo formation in front to
end simulations, caused by current fluctuations, filamented RFQ output
distribution and enhanced by accumulated field errors.

</DOC>
<DOC>
<DOCNO> 101993 </DOCNO>
The Jacobson radical for analytic crossed products


  We characterise the (Jacobson) radical of the analytic crossed product of
C_0(X) by the non-negative integers (Z_+), answering a question first raised by
Arveson and Josephson in 1969. In fact, we characterise the radical of analytic
crossed products of C_0(X) by (Z_+)^d. The radical consists of all elements
whose `Fourier coefficients' vanish on the recurrent points of the dynamical
system (and the first one is zero). The multi-dimensional version requires a
variation of the notion of recurrence, taking into account the various degrees
of freedom.

</DOC>
<DOC>
<DOCNO> 13750 </DOCNO>
Ferromagnetic phase transition in a Heisenberg fluid: Monte Carlo


  The magnetic phase transition in a Heisenberg fluid is studied by means of
the finite size scaling (FSS) technique. We find that even for larger systems,
considered in an ensemble with fixed density, the critical exponents show
deviations from the expected lattice values similar to those obtained
previously. This puzzle is clarified by proving the importance of the leading
correction to the scaling that appears due to Fisher renormalization with the
critical exponent equal to the absolute value of the specific heat exponent
$\alpha$. The appearance of such new corrections to scaling is a general
feature of systems with constraints.

</DOC>
<DOC>
<DOCNO> 12220 </DOCNO>
Classification of one-dimensional quasilattices into mutual


  One-dimensional quasilattices are classified into mutual local-derivability
(MLD) classes on the basis of geometrical and number-theoretical
considerations. Most quasilattices are ternary, and there exist an infinite
number of MLD classes. Every MLD class has a finite number of quasilattices
with inflation symmetries. We can choose one of them as the representative of
the MLD class, and other members are given as decorations of the
representative. Several MLD classes of particular importance are listed. The
symmetry-preserving decorations rules are investigated extensively.

</DOC>
<DOC>
<DOCNO> 71777 </DOCNO>
Non-Thermal Dark Matter, High Energy Cosmic Rays and Late-Decaying


  It has been suggested that the origin of cosmic rays above the GZK limit
might be explained by the decay of particles, X, with mass of the order of
10^{12} GeV. Generation of heavy particles from inflationary quantum
fluctuations is a prime candidate for the origin of the decaying X particles.
 It has also been suggested that the problem of non-singular galactic halos
might be explained if dark matter originates non-thermally from the decay of
particles, Y, such that there is a free-streaming length of the order of
0.1Mpc. Here we explore the possibility that quantum fluctuations might account
for the Y particles as well as the X particles. For the case of non-thermal
WIMP dark matter with unsuppressed weak interactions we find that there is a
general problem with deuterium photo-dissociation, disfavouring WIMP dark
matter candidates. For the case of more general dark matter particles, which
may have little or no interaction with conventional matter, we discuss the
conditions under which X and Y scalars or fermions can account for non-thermal
dark matter and cosmic rays. For the case where X and Y scalars are
simultaneously produced, we show that galactic halos are likely to have a
dynamically significant component of X scalar cold dark matter in addition to
the dominant non-thermal dark matter component.

</DOC>
<DOC>
<DOCNO> 102186 </DOCNO>
Noncommutative Chern-Simons terms and the noncommutative vacuum


  It is pointed out that the space noncommutativity parameters $theta^{\mu
\nu}$ in noncommutative gauge theory can be considered as a set of
superselection parameters, in analogy with the theta-angle in ordinary gauge
theories. As such, they do not need to enter explicitly into the action. A
simple generic formula is then suggested to reproduce the Chern-Simons action
in noncommutative gauge theory, which reduces to the standard action in the
commutative limit but in general implies a cascade of lower-dimensional
Chern-Simons terms. The presence of these terms in general alters the vacuum
structure of the theory and nonstandard gauge theories can emerge around the
new vacua.

</DOC>
<DOC>
<DOCNO> 102307 </DOCNO>
Monodromy groups of irregular elliptic surfaces


  Monodromy groups, i.e. the groups of isometries of the intersection lattice
L_X:=H_2/torsion generated by the monodromy action of all deformation families
of a given surface, have been computed in math.AG/0006231 for any minimal
elliptic surface with p_g>q=0. New and refined methods are now employed to
address the cases of minimal elliptic surfaces with p_g+1>q>0. To this end we
find explicit families such that any isometry is in the group generated by
their monodromies or does not respect the invariance of the canonical class or
the spinor norm. The monodromy action is moreover shown to act by the full
symplectic group on the first homology modulo torsion.

</DOC>
<DOC>
<DOCNO> 119918 </DOCNO>
The LBDS Hercules sample of millijansky radio sources at 1.4 GHz: I.


  The results are presented of an extensive programme of optical and infrared
imaging of radio sources in a complete subsample of the Leiden-Berkeley Deep
Survey. The LBDS Hercules sample consists of 72 sources observed at 1.4 GHz,
with flux densities S(1.4) >= 1.0 mJy, in a 1.2 deg^2 region of Hercules. This
sample is almost completely identified in the g, r, i and K bands, with some
additional data available at J and H. The magnitude distributions peak at r ~=
22 mag, K ~= 16 mag and extend down to r ~= 26 mag, K ~= 21 mag. The K-band
magnitude distributions for the radio galaxies and quasars are compared with
those of other radio surveys. At S(1.4) <~ 1 Jy, the K-band distribution does
not change significantly with radio flux density. The sources span a broad
range of colours, with several being extremely red (r-K >~ 6). Although small,
this is the most optically complete sample of millijansky radio sources
available at 1.4 GHz, and is ideally suited to study the evolution of the radio
luminosity function out to high redshifts.

</DOC>
<DOC>
<DOCNO> 120223 </DOCNO>
Frequency decomposition of astrometric signature of planetary systems


  We present theoretical analysis of the astrometric searches for extrasolar
planets with the Space Interferometry Mission (SIM). Particularly, we derive a
model for the future measurements with SIM and discuss the problem of reliable
estimation of orbital elements of planets. For this purpose we propose a new
method of data analysis and present a numerical test of its application on
simulated SIM astrometric measurements of $\upsilon$ Andromedae planetary
system. We demonstrate that our approach allows successfull determination of
its orbital elements.

</DOC>
<DOC>
<DOCNO> 85351 </DOCNO>
Variable cosmological term - geometry and physics


  We describe the dynamics of a cosmological term in the spherically symmetric
case by an r-dependent second rank symmetric tensor \Lambda_{\mu\nu} invariant
under boosts in the radial direction. The cosmological tensor \Lambda_{\mu\nu}
represents the extension of the Einstein cosmological term \Lambda g_{\mu\nu}
which allows a cosmological constant be variable. This possibility is based on
the Petrov classification scheme and Einstein field equations in the
spherically symmetric case. The inflationary equation of state is satisfied by
the radial pressure p_r^{\Lambda}=-\rho^{\Lambda}. The tangential pressure is
calculated from the conservation equation \Lambda^{\mu}_{\nu;\mu}=0. The
solutions to the Einstein equations with cosmological term \Lambda_{\mu\nu}
describe several types of globally regular self-gravitating vacuum
configurations including vacuum nonsingular black holes. In this case the
global structure of space-time contains an infinite set of black and white
holes whose singularities are replaced with the value of cosmological constant
of the scale of symmetry restoration, at the background of asymptotically flat
or asymptotically de Sitter universes. We outline \Lambda white hole geometry
and estimate probability of quantum birth of baby universes inside a \Lambda
black hole. In the course of Hawking evaporation of a \Lambda black hole, a
second-order phase transition occurs, and globally regular configuration
evolves towards a self-gravitating particlelike structure at the background of
the Minkowski or de Sitter space.

</DOC>
<DOC>
<DOCNO> 119241 </DOCNO>
X-ray Astronomy with CCDs: Calibration of the Advanced CCD Imaging


  (ABRIDGED)
   This dissertation concerns the use of CCDs for for X-ray astronomy. Part I
of this thesis focuses on the calibration of the Advanced CCD Imaging
Spectrometer (ACIS), one of the two primary focal plane instruments on the
Chandra X-ray Observatory. I begin by presenting a series of measurements made
using undispersed synchrotron radiation. I analyzed the results of these
experiments to extract parameters necessary to model the absolute detection
efficiency of CCDs used as reference standards for ACIS characterization. I
also discuss a novel "mesh" technique I pioneered to non-destructively measure
the sub-pixel structure of CCDs, including the channel stops and gates. Guided
by the results of the mesh experiments, I performed additional measurements to
constrain recombination effects in the channel stops.
  Part II of this thesis concerns the X-ray properties of rotation- powered
(radio) pulsars. High energy observations serve as a powerful diagnostic of the
energetics and emission mechanisms of neutron stars. I analyze ASCA and ROSAT
observations of three young pulsars which are particularly well-suited for
addressing these issues. I also present observations of the rotation-powered
pulsar with the highest known magnetic field, and describe how the results
relate to anomalous X-ray pulsars, another type of neutron star. Finally, I
analyze Chandra observations of the supernova remnant Cas A. These data fully
demonstrate the capabilities of ACIS and reveal a previously unknown point
source at the center of the remnant.

</DOC>
<DOC>
<DOCNO> 10935 </DOCNO>
A symmetric polymer blend confined into a film with antisymmetric


  We study the phase behavior of a symmetric binary polymer blend which is
confined into a thin film. The film surfaces interact with the monomers via
short range potentials. We calculate the phase behavior within the
self-consistent field theory of Gaussian chains. Over a wide range of
parameters we find strong first order wetting transitions for the semi-infinite
system, and the interplay between the wetting/prewetting behavior and the phase
diagram in confined geometry is investigated. Antisymmetric boundaries, where
one surface attracts the A component with the same strength than the opposite
surface attracts the B component, are applied. The phase transition does not
occur close to the bulk critical temperature but in the vicinity of the wetting
transition. For very thin films or weak surface fields one finds a single
critical point at $\phi_c=1/2$. For thicker films or stronger surface fields
the phase diagram exhibits two critical points and two concomitant coexistence
regions. Only below a triple point there is a single two phase coexistence
region. When we increase the film thickness the two coexistence regions become
the prewetting lines of the semi-infinite system, while the triple temperature
converges towards the wetting transition temperature from above. The behavior
close to the tricritical point, which separates phase diagrams with one and two
critical points, is studied in the framework of a Ginzburg-Landau ansatz.
Two-dimensional profiles of the interface between the laterally coexisting
phases are calculated, and the interfacial and line tensions analyzed. The
effect of fluctuations and corrections to the self-consistent field theory are
discussed.

</DOC>
<DOC>
<DOCNO> 117423 </DOCNO>
Biased Estimates of Omega from Comparing Smoothed Predicted Velocity


  We show that a regression of unsmoothed peculiar velocity measurements
against peculiar velocities predicted from a smoothed galaxy density field
leads to a biased estimate of the cosmological density parameter Omega, even
when galaxies trace the underlying mass distribution and galaxy positions and
velocities are known perfectly. The bias arises because the errors in the
predicted velocities are correlated with the predicted velocities themselves.
We investigate this bias using cosmological N-body simulations and analytic
arguments. In linear perturbation theory, for cold dark matter power spectra
and Gaussian or top hat smoothing filters, the bias in Omega is always
positive, and its magnitude increases with increasing smoothing scale. This
linear calculation reproduces the N-body results for Gaussian smoothing radii
R_s > 10 Mpc/h, while non-linear effects lower the bias on smaller smoothing
scales, and for R_s < 3 Mpc/h Omega is underestimated rather than
overestimated. The net bias in Omega for a given smoothing filter depends on
the underlying cosmological model. The effect on current estimates of Omega
from velocity-velocity comparisons is probably small relative to other
uncertainties, but taking full advantage of the statistical precision of future
peculiar velocity data sets will require either equal smoothing of the
predicted and measured velocity fields or careful accounting for the biases
discussed here.

</DOC>
<DOC>
<DOCNO> 71688 </DOCNO>
Sphaleron in the Dilatonic Gauge Field Theory


  Motivated by the Kaluza-Klein theory with a large number of extra spacetime
dimensions, we present a numerical study of static, spherically symmetric
sphaleron solutions coupled to the dilaton fields. We show that sphalerons may
have different dilaton cloud configurations, resulting in new massive
sphalerons, in general. However, there exist different cloud configurations
with different values of the dilaton mass.

</DOC>
<DOC>
<DOCNO> 102402 </DOCNO>
Gross-Hopkins duality


  We give a new and simpler proof of a result of Hopkins and Gross relating
Brown-Comenetz duality to Spanier-Whitehead duality in the K(n)-local stable
homotopy category.

</DOC>
<DOC>
<DOCNO> 40677 </DOCNO>
Predictive SUSY GUT Model for CP Violation, Fermion Masses and Mixings


  CP violation, fermion masses and mixing angles including that of neutrinos
are studied in an SUSY SO(10)$\times \Delta (48)\times$ U(1) model. The
nonabelian SU(3) discrete family symmetry $\Delta(48)$ associated with a simple
scheme of U(1) charge assignment on various fields concerned in superpotential
leads to unique Yukawa coupling matrices with zero textures. Thirteen
parameters involving masses and mixing angles in the quark and charged lepton
sector are successfully predicted by only four parameters. The masses and
mixing angles for the neutrino sector could also be predicted by constructing
an appropriate heavy Majorana neutrino mass matrix without involving new
parameters. It is found that the atmospheric neutrino deficit, the mass limit
put by hot dark matter and the LSND $\bar{\nu}_{\mu} \to \bar{\nu}_{e}$ events
may simultaneously be explained, but solar neutrino puzzle can be solved only
by introducing a sterile neutrino. An additional parameter is added to obtain
the mass and mixing of the sterile neutrino. The hadronic parameters $B_{K}$
and $f_{B}\sqrt{B}$ are extracted from the observed $K^{0}$-$\bar{K}^{0}$ and
$B^{0}$-$\bar{B}^{0}$ mixings respectively. The direct CP violation
($\epsilon'/\epsilon$) in kaon decays and the three angles $\alpha$, $\beta$
and $\gamma$ of the unitarity triangle in the CKM matrix are also presented.
More precise measurements of $\alpha_{s}(M_{Z})$, $|V_{cb}|$,
$|V_{ub}/V_{cb}|$, $m_{t}$, as well as various CP violation and neutrino
oscillation experiments will provide an important test for the present model
and guide us to a more fundamental theory.

</DOC>
<DOC>
<DOCNO> 69950 </DOCNO>
Thermal Freeze-out and Longitudinally Non-uniform Collective Expansion


  The non-uniform longitudinal flow model (NUFM) propsed recently is extended
to include also transverse flow. The resulting longitudinally non-uniform
collective expansion model (NUCEM) is applied to the calculation of rapidity
distribution of kaons, lambdas and protons in relativistic heavy ion collisions
at CERN-SPS energies. The model results are compared with the 200 A GeV/$c$ S-S
and 158 A GeV/$c$ Pb-Pb collision data. The central dips observed in
experiments are reproduced in a natural way.

</DOC>
<DOC>
<DOCNO> 117536 </DOCNO>
Disc galaxy evolution models in a hierarchical formation scenario:


  We predict the structure and dynamics of disc galaxies using galaxy evolution
models within a hierarchical formation scenario The halo mass aggregation
histories, for a Lambda CDM model, were generated and used to calculate the
virialization of dark matter (DM) haloes. A diversity of halo density profiles
were obtained, the most typical one being close to the NFW profile. We modeled
the formation of discs in centrifugal equilibrium within the evolving DM haloes
using gas accretion rates proportional to the halo mass aggregation rates, and
assuming detailed angular momentum conservation. We calculated the
gravitational interactions between halo and disc, and the hydrodynamics, star
formation, and evolution of the galaxy discs. We found that the slope and
zero-point of the infrared Tully-Fisher relations (TFR) may be explained as a
direct consequence of the cosmological initial conditions. This relation is
almost independent of the assumed disc mass fraction. The rms scatter of the
TFR originates mainly from the scatter in the DM halo structure and, to a minor
extension, from the dispersion of the primordial spin parameter. The scatter
obtained does not disagree with the observational estimates. Our models allow
us to understand why the residuals of the TFR do not correlate significantly
with disc size or surface brightness (SB), and why low and high SB galaxies
have the same TFR. The correlations between gas fraction and SB, and between
scale length and V_max agree with those observed. The discs present nearly
exponential SB distributions. The shape of the rotation curves changes with the
SB and is nearly flat for most cases. The rotation curve decompositions show a
dominance of DM down to very small radii. The introduction of shallow cores in
the DM halo attenuates this difficulty.

</DOC>
<DOC>
<DOCNO> 116343 </DOCNO>
Structural information from multilamellar liposomes at full hydration:


  We present a novel method for analyzing Small Angle X-ray Scattering data on
multilamellar phospholipid bilayer systems at full hydration. The method
utilizes a modified Caille' theory structure factor in combination with a
Gaussian model representation of the electron density profile such that it
accounts also for the diffuse scattering between Bragg peaks. Thus, the method
can retrieve structural information even if only a few orders of diffraction
are observed. We further introduce a new procedure to derive fundamental
parameters, such as area per lipid, membrane thickness, and number of water
molecules per lipid, directly from the electron density profile without the
need of additional volumetric measurements. The theoretical apparatus is
applied to experimental data on
1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine and
1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine liposome preparations.

</DOC>
<DOC>
<DOCNO> 10995 </DOCNO>
The Channel Capacity of a Fiber Optics Communication System:


  We consider the communication channel given by a fiber optical transmission
line. We develop a method to perturbatively calculate the information capacity
of a nonlinear channel, given the corresponding evolution equation. Using this
technique, we compute the decrease of the channel capacity to the leading order
in the perturbative parameter for fiber optics communication systems.

</DOC>
<DOC>
<DOCNO> 100323 </DOCNO>
Lagrangian and Hamiltonian Formalism for Constrained Variational


  We consider solutions of Lagrangian variational problems with linear
constraints on the derivative. These solutions are given by curves $\gamma$ in
a differentiable manifold $M$ that are everywhere tangent to a smooth
distribution $\mathcal D$ on $M$; such curves are called horizontal. We study
the manifold structure of the set $\Omega_{P,Q}(M,\mathcal D)$ of horizontal
curves that join two submanifolds $P$ and $Q$ of $M$. We consider an action
functional $\mathcal L$ defined on $\Omega_{P,Q}(M,\mathcal D)$ associated to a
time-dependent Lagrangian defined on $\mathcal D$. If the Lagrangian satisfies
a suitable hyper-regularity assumption, it is shown how to construct an
associated degenerate Hamiltonian $H$ on $TM^*$ using a general notion of {\em
Legendre transform} for maps on vector bundles. We prove that the solutions of
the Hamilton equations of $H$ are precisely the critical points of $\mathcal
L$.

</DOC>
<DOC>
<DOCNO> 11517 </DOCNO>
Local field theory for disordered itinerant quantum ferromagnets


  An effective field theory is derived that describes the quantum critical
behavior of itinerant ferromagnets in the presence of quenched disorder. In
contrast to previous approaches, all soft modes are kept explicitly. The
resulting effective theory is local and allows for an explicit perturbative
treatment. It is shown that previous suggestions for the critical fixed point
and the critical behavior are recovered under certain assumptions. The validity
of these assumptions is discussed in the light of the existence of two
different time scales. It is shown that, in contrast to previous suggestions,
the correct fixed point action is not Gaussian, and that the previously
proposed critical behavior was correct only up to logarithmic corrections. The
connection with other theories of disordered interacting electrons, and in
particular with the resolution of the runaway flow problem encountered in these
theories, is also discussed.

</DOC>
<DOC>
<DOCNO> 9518 </DOCNO>
Exact versus mean-field description of the Bose-Einstein condensate: a


  We study a system of trapped bosonic particles interacting by model harmonic
forces. Our model allows for detailed examination of the notion of an order
parameter (a condensate wave function). By decomposing a single particle
density matrix into coherent eigenmodes we study an effect of interaction on
the condensate. We show that sufficiently strong interactions cause that the
condensate disappears even if the whole system is in its lowest energy state.
In the second part of our paper we discuss the validity of the Bogoliubov
approximation by comparing its predictions with results inferred from the
exactl y soluble model. In particular we examine an energy spectrum,
occupation, and fluctuations of the condensate. We conclude that Bogoliubov
approach gives quite accurate description of the system in the limit of weak
interactions.

</DOC>
<DOC>
<DOCNO> 122798 </DOCNO>
Evidence of magnetic accretion in an SW Sex star: discovery of variable


  We report on the discovery of variable circular polarization in the SW Sex
star LS Pegasi. The observed modulation has an amplitude of ~0.3 % and a period
of 29.6 minutes, which we assume as the spin period of the magnetic white
dwarf. We also detected periodic flaring in the blue wing of Hbeta, with a
period of 33.5 minutes. The difference between both frequencies is just the
orbital frequency, so we relate the 33.5-min modulation to the beat between the
orbital and spin period. We propose a new accretion scenario in SW Sex stars,
based on the shock of the disk-overflown gas stream against the white dwarf's
magnetosphere, which extends to the corotation radius. From this geometry, we
estimate a magnetic field strength of B(1) ~ 5-15 MG. Our results indicate that
magnetic accretion plays an important role in SW Sex stars and we suggest that
these systems are probably Intermediate Polars with the highest mass accretion
rates.

</DOC>
<DOC>
<DOCNO> 85048 </DOCNO>
Singularity in 2+1 dimensional AdS-scalar black hole


  We study the spacetime singularity in 2+1 dimensional AdS-scalar black hole
with circular symmetry using a quasi-homogeneous model. We show that this is a
spacelike, scalar curvature, deformationally strong singularity.

</DOC>
<DOC>
<DOCNO> 121113 </DOCNO>
Stellar Populations in the Phoenix Dwarf (dIrr/dSph) Galaxy as Observed


  We present HST/WFPC2 photometry of the central regions of the Phoenix dwarf.
Accurate photometry allows us to: 1) confirm the existence of the horizontal
branch previously detected by ground-based observations, and use it to
determine a distance to Phoenix, 2) clearly detect the existence of multiple
ages in the stellar population of Phoenix, 3) determine a mean metallicity of
the old red giant branch stars in Phoenix, and suggest that Phoenix has evolved
chemically over its lifetime, 4) extract a rough star formation history for the
central regions which suggests that Phoenix has been forming stars roughly
continuously over its entire lifetime.

</DOC>
<DOC>
<DOCNO> 122044 </DOCNO>
Timing Analysis of the Light Curve of the Dipping-Bursting X-ray Binary


  We present the timing analysis results for our observations of the x-ray dip
source X1916-053 conducted with RXTE between February and October of 1996. Our
goal was to finally measure the binary period - as either the x-ray dip period
or ~1% longer optical modulation period, thereby establishing if the binary has
a precessing disk (SU UMa model) or a third star (triple model). Combined with
historical data (1979-96), the x-ray dip period is measured to be 3000.6508
$\pm$ 0.0009 sec with a 2$\sigma$ upper limit $|\dot P| \leq 2.06 \times
10^{-11}$. From our quasi-simultaneous optical observations (May 14-23, 1996)
and historical data (1987-96), we measure the optical modulation period to be
3027.5510 $\pm$ 0.0052 sec with a 2$\sigma$ upper limit $|\dot P| \leq 2.28
\times 10^{-10}$. The two periods are therefore each stable (over all recorded
data) and require a $3.9087 \pm 0.0008$d beat period. This beat period, and
several of its harmonics is also observed as variations in the dip shape. Phase
modulation of x-ray dips, observed in a 10 consecutive day observation, is
highly correlated with the $\sim$3.9d dip shape modulation. The 1987-1996
optical observations show that the optical phase fluctuations are a factor of 3
larger than those in the x-ray. We discuss SU UMa vs. triple models to describe
the X1916-053 light curve behavior and conclude that the x-ray dip period, with
smaller phase jitter, is probably the binary period so that the required
precession is most likely similar to that observed in SU UMa and x-ray nova
systems. However the ``precession'' period stability and especially the fact
that the times of x-ray bursts may partially cluster to occur just after x-ray
dips, continue to suggest that this system may be a hierarchical triple.

</DOC>
<DOC>
<DOCNO> 101108 </DOCNO>
A tensor form of the Dirac equation


  We prove the following theorem: the Dirac equation for an electron (invented
by P.A.M.Dirac in 1928) can be written as a tensor equation. An equation is
called a tensor equation if all values in it are tensors and all operations in
it take tensors to tensors.

</DOC>
<DOC>
<DOCNO> 9369 </DOCNO>
Galaxy Distributions and Tsallis Statistical Mechanics


  Large-scale astrophysical systems are non-extensive due to their long-range
force of gravity. Here we show an approach toward the statistical mechanics of
such self-gravitating systems (SGS). This is a generalization of the standard
statistical mechanics based on the new definition of entropy; Tsallis
statistical mechanics. Developing the composition of entropy and the
generalized Euler relation, we investigate the galaxy distributions in
count-in-cell method. This is applied to the data of CfA II South redshift
survey.

</DOC>
<DOC>
<DOCNO> 8928 </DOCNO>
Stability of Trapped Ultracold Fermi Gases Using Effective s- and p-Wave


  The stability of trapped dilute Fermi gases against collapse towards large
densities is studied. A hermitian effective contact-interaction for all partial
waves is derived, which is particularly suited for a mean-field description of
these systems. Including the s- and p-wave parts explicit stability conditions
and critical particle numbers are given as function of the scattering lengths.
The p-wave contribution determines the stability of a single-component gas and
can substantially modify the stability of a two-component gas. Moreover it may
give rise to a novel p-wave stabilized high-density phase.

</DOC>
<DOC>
<DOCNO> 150555 </DOCNO>
Orientifolds with discrete torsion


  We show how discrete torsion can be implemented in D=4, N=1 type IIB
orientifolds. Some consistency conditions are found from the closed string and
open string spectrum and from tadpole cancellation. Only real values of the
discrete torsion parameter are allowed, i.e. epsilon=+-1. Orientifold models
are related to real projective representations. In a similar way as complex
projective representations are classified by H^2(Gamma,C^*)=H^2(Gamma,U(1)),
real projective representations are characterized by
H^2(Gamma,R^*)=H^2(Gamma,Z_2). Four different types of orientifold
constructions are possible. We classify these models and give the spectrum and
the tadpole cancellation conditions explicitly.

</DOC>
<DOC>
<DOCNO> 8228 </DOCNO>
Memory Effects in Granular Material


  We present a combined experimental and theoretical study of memory effects in
vibration-induced compaction of granular materials. In particular, the response
of the system to an abrupt change in shaking intensity is measured. At short
times after the perturbation a granular analog of aging in glasses is observed.
Using a simple two-state model, we are able to explain this short-time
response.
 We also discuss the possibility for the system to obey an approximate
pseudo-fluctuation-dissipation theorem relationship and relate our work to
earlier experimental and theoretical studies of the problem.

</DOC>
<DOC>
<DOCNO> 101269 </DOCNO>
Theta constants associated to cubic three folds


  For a cubic surface X, by considering the intermediate Jacobian J(Y) of the
triple covering Y of the 3-dimensional projective space branching along X,
Allcock, Carlson and Toledo constructed a period map per from the family of
marked cubic surfaces to the four dimensional complex ball embedded in the
Siegel upper half space of degree 5. We give an expression of the inverse of
per in terms of theta constants by constructing an isomorphism between J(Y) and
a Prym variety of a cyclic 6-ple covering of the projective line branching at
seven points.

</DOC>
<DOC>
<DOCNO> 70300 </DOCNO>
Solar neutrino oscillation from large extra dimensions


  A plausible explanation for the existence of additional light sterile
neutrinos is that they correspond to modulini, fermionic partners of moduli,
which propagate in new large dimensions. We discuss the phenomenological
implications of such states and show that solar neutrino oscillation is well
described by small angle MSW oscillation to the tower of Kaluza Klein states
associated with the modulini. In the optimal case the recoil electron energy
spectrum agrees precisely with the measured one, in contrast to the single
sterile neutrino case which is disfavoured. We also consider how all
oscillation phenomena can be explained in a model including bulk neutrino
states. In particular, we show that a naturally maximal mixing for atmospheric
neutrinos can be easily obtained.

</DOC>
<DOC>
<DOCNO> 122573 </DOCNO>
The protostellar system HH108MMS


  We probe the region around the protostar HH108MMS by deep mid infrared
photometric and polarimetric imaging. The protostar is detected at 14mu in
absorption against the diffuse background. Next to HH108MMS, we find a second
absorbing core, named Q1, and the young stellar object IRAS18331-0035 which is
more advanced in its evolution and already seen in emission at 12mu and 14mu.
HH108MMS, Q1 and IRAS18331-0035 form a triplet along an extended filamentary
absorption feature. From the variation of the surface brightness across the
source, we derive for HH108MMS and Q1 the optical depth and density profile. As
HH108MMS is also seen in the millimeter dust emission, we can derive the ratio
of the dust extinction coefficients at 14mu and 1.3mm and obtain kappa(14mu) /
kappa(1300mu) ~ 470. Because models for the dust in the diffuse interstellar
medium predict a ratio of around 2000, our value points to fluffy composite
grains which are expected to prevail in dense and cold environments. First mid
infrared polarisation images of pre--stellar absorbing cores are presented. At
12mu and 14mu the polarisation of the region around HH108MMS is strong (> 15%)
and tightly correlated with the source triplet. We demonstrate that the high
degree of polarisation can be explained by extinction of rotationally aligned
dust particles of moderate elongation.

</DOC>
<DOC>
<DOCNO> 69052 </DOCNO>
Phenomenological Consequences of Right-handed Down Squark Mixings


  The mixings of $d_R$ quarks, hidden from view in Standard Model (SM), are
naturally the largest if one has an Abelian flavor symmetry. With supersymmetry
(SUSY) their effects can surface via $\tilde d_R$ squark loops. Squark and
gluino masses are at TeV scale, but they can still induce effects comparable to
SM in $B_d$ (or $B_s$) mixings, while $D^0$ mixing could be close to recent
hints from data. In general, CP phases would be different from SM, as may be
indicated by recent B Factory data. Presence of non-standard soft SUSY
breakings with large $\tan\beta$ could enhance $b\to d\gamma$ (or $s\gamma$)
transitions.

</DOC>
<DOC>
<DOCNO> 70989 </DOCNO>
A Primer on Instantons in QCD


  These are the extended notes of a set of lectures given at the ``12th
Workshop on Hadronic Interactions'' at the IF/UERJ, Rio de Janeiro (31. 5. - 2.
6. 2000). The lectures aim at introducing essential concepts of instanton
physics, with emphasis on the role of instantons in generating tunneling
amplitudes, vacuum structure, and the induced quark interactions associated
with the axial anomaly. A few examples for the impact of instantons on the
physics of hadrons are also mentioned.

</DOC>
<DOC>
<DOCNO> 178678 </DOCNO>
The rho meson in a nuclear medium


  In this work, propagation properties of the rho meson in symmetric nuclear
matter are studied. We make use of a coupled channel unitary approach to
meson-meson scattering, calculated from the lowest order Chiral Perturbation
Theory lagrangian including explicit resonance fields. Low energy chiral
constraints are considered by matching our expressions to those of one loop
Ch.P.T. To account for the medium corrections, the rho couples to pion-pion and
kaon-antikaon pairs which are properly renormalized in the nuclear medium.

</DOC>
<DOC>
<DOCNO> 12426 </DOCNO>
Unusual temperature dependence of the London penetration depth in


  The temperature dependence of the in-plane, \lambda_{\parallel}, and
interplane, \lambda_{\perp}, London penetration depth was measured in the
metal-free all-organic superconductor \beta-ET (see title) ($T_c \approx$ 5.2
K). \lambda_{\parallel} ~T^3 up to 0.5 Tc, a power law previously observed only
in materials thought to be p-wave superconductors. \lambda_{\perp} is larger
than the sample dimensions down to the lowest temperatures (0.35 K), implying
an anisotropy of \lambda_{\perp}/\lambda_{\parallel} ~ 400-800.

</DOC>
<DOC>
<DOCNO> 150839 </DOCNO>
Anomaly cancellation in M-theory on orbifolds


  We present calculation of the anomaly cancellation in M-theory on orbifolds
$S^1/Z_2$ and $T^5/Z_2$ in the upstairs approach. The main requirement that
allows one to uniquely define solutions to the modified Bianchi identities in
this case is that the field strength $G$ be globally defined on $S^1$ or $T^5$
and properly transforming under $Z_2$. We solve for general $G$ that satisfies
these requirements and explicitly construct anomaly-free theories in the
upstairs approach. We also obtain the solutions in the presence of five-branes.
All these constructions show equivalence of the downstairs and upstairs
approaches. For example in the $S^1/Z_2$ case the ten-dimensional gauge
coupling and the anomaly cancellation at each wall are the same as in the
downstairs approach.

</DOC>
<DOC>
<DOCNO> 40606 </DOCNO>
New Results on Rare and Forbidden Semileptonic $K^+$ Decays


  Experiment E865 at the Brookhaven AGS was set up primarily to search for the
lepton flavour violating decay $K^+\to \pi^+\mu^+e^-$ ($K_{\pi\mu e}$) with
high sensitivity. The flexibility of the apparatus allowed also to obtain more
than an order of magnitude larger than previously available event samples on
the following decay modes: $ \pi^+e^+e^- (K_{\pi ee})$, $\pi^+\mu^+\mu^-
(K_{\pi\mu\mu})$, $\pi^+\pi^-e^+\nu_e (K_{e4})$, $\mu^+e^+e^-\nu_\mu$, and
$e^+e^+e^-\nu_e$. The report focusses on the $K_{\pi\mu e}$ results and those
on other lepton flavour violating decays as well as the $K_{e4}$ data, from
which a new, quite precise value for the s-wave $\pi\pi$ scattering length can
be deduced.

</DOC>
<DOC>
<DOCNO> 122742 </DOCNO>
Emission from Dust in Galaxies: Metallicity Dependence


  Infrared (IR) dust emission from galaxies is frequently used as an indicator
of star formation rate (SFR). However, the effect of the dust-to-gas ratio
(i.e., amount of the dust) on the conversion law from IR luminosity to SFR has
not so far been considered. Then, in this paper, we present a convenient
analytical formula including this effect. In order to obtain the dependence on
the dust-to-gas ratio, we extend the formula derived in our previous paper, in
which a theoretical formula converting IR luminosity to SFR was derived. That
formula was expressed as ${\rm SFR}/(M_\odot~{\rm yr}^{-1})=\{3.3\times
10^{-10}(1- \eta)/(0.4-0.2f+0.6\epsilon)\} (L_{\rm IR}/L_\odot)$, where f is
the fraction of ionizing photons absorbed by hydrogen, $\epsilon$ is the
efficiency of dust absorption for nonionizing photons, $\eta$ is the cirrus
fraction of observed dust luminosity, and $L_{\rm IR}$ is the observed
luminosity of dust emission in the 8-1000-$\mu$m range. Our formula explains
the IR excess of the Galaxy and the Large Magellanic Cloud. In the current
paper, especially, we present the metallicity dependence of our conversion law
between SFR and $L_{\rm IR}$. This is possible since both f and $\epsilon$ can
be estimated via the dust-to-gas ratio, which is related to metallicity. We
have confirmed that the relation between the metallicity and the dust-to-gas
ratio is applied to both giant and dwarf galaxies. Finally, we apply the result
to the cosmic star formation history. We find that the comoving SFR at z=3
calculated from previous empirical formulae is underestimated by a factor of
4-5.

</DOC>
<DOC>
<DOCNO> 150832 </DOCNO>
Kinks from Dynamical Systems: Domain Walls in a Deformed O(N) Linear


  It is shown how a integrable mechanical system provides all the localized
static solutions of a deformation of the linear O(N)-sigma model in two
space-time dimensions. The proof is based on the Hamilton-Jacobi separability
of the mechanical analogue system that follows when time-independent field
configurations are being considered. In particular, we describe the properties
of the different kinds of kinks in such a way that a hierarchical structure of
solitary wave manifolds emerges for distinct N.

</DOC>
<DOC>
<DOCNO> 121184 </DOCNO>
A ridge of recent massive star formation between Sgr B2M and Sgr B2N


  We present single dish and interferometric maps of several rotational
transitions of HC3N vibrationally excited levels towards Sgr B2. The single
dish maps show, for the first time, new four bright clumps (Sgr B2R1 to B2R4)
in the ridge connecting the main cores Sgr B2M and Sgr B2N, and a low
brightness extended region to the west of the ridge (Sgr B2W). The physical
properties and the kinematics of all hot cores have been derived from the HC3N*
lines. Our high angular resolution images show that the Sgr B2N hot core breaks
in two different hot cores, Sgr B2N1 and N2, with different radial velocities
and separated by 2 arcsec in declination. We find that the excitation of the
HC3N* emission in all hot cores can be represented by a single temperature and
that the linewidth of the HC3N* rotational lines arising from different
vibrational levels systematically decreases as the energy of the vibrational
level increases. The systematic trend in the linewidth is likely related to the
increase of the velocity as the distance to the exciting source increases. The
different HC3N abundances in the hot cores reflect different stages of
evolution due to time dependent chemistry and/or photo-dissociation by UV
radiation from nearby HII regions. We propose that Sgr B2M and B2N contain a
cluster of 20-30 hot cores and that the Sgr B2R1-B2R4 hot cores represent
isolated formation of massive stars.

</DOC>
<DOC>
<DOCNO> 13450 </DOCNO>
Hamiltonian in Financial Markets


  A statistical physics model for the time evolutions of stock portfolios is
proposed. In this model the time series of price changes are coded into the
sequences of up and down spins. The Hamiltonian of the system is introduced and
is expressed by spin-spin interactions as in spin glass models of disordered
magnetic systems. The interaction coefficients between two stocks are
determined by empirical data coded into up and down spin sequences using
fluctuation-response theorem. Monte Carlo simulations are performed and the
resultant probability densities of the system energy and magnetization show
good agreement with empirical data.

</DOC>
<DOC>
<DOCNO> 84583 </DOCNO>
Equilibrium Configuration of Black Holes and the Inverse Scattering


  The inverse scattering method is applied to the investigation of the
equilibrium configuration of black holes. A study of the boundary problem
corresponding to this configuration shows that any axially symmetric,
stationary solution of the Einstein equations with disconnected event horizon
must belong to the class of Belinskii-Zakharov solutions. Relationships between
the angular momenta and angular velocities of black holes are derived.

</DOC>
<DOC>
<DOCNO> 70783 </DOCNO>
An estimate of a lower bound on the masses of mirror baryons


  We consider the most favorable conditions to indirectly observe the mixing of
ordinary and mirror hadrons in non-leptonic and weak radiative decays of
hyperons. This allows us to set a lower bound on the masses of mirror baryons.
This bound turns out to be impressively high, of the order of $10^6$GeV.

</DOC>
<DOC>
<DOCNO> 72214 </DOCNO>
String models of glueballs and the spectrum of SU(N) gauge theories in


  The spectrum of glueballs in 2+1 dimensions is calculated within an extended
class of Isgur-Paton flux tube models and is compared to lattice calculations
of the low-lying SU(N) glueball mass spectra. Our modifications of the model
include a string curvature term and different ways of dealing with the flux
tube width. We find that the generic model is remarkably successful at
reproducing the positive charge conjugation, C=+, sector of the spectrum. The
only large (and robust) discrepancy involves the 0-+ state. This raises the
interesting possibility that the lattice spin identification is mistaken and
that this state is in fact 4-+. In addition, the Isgur-Paton model does not
incorporate any mechanism for splitting C=+ from C=- (in contrast to the case
in 3+1 dimensions), while the `observed' spectrum shows a substantial
splitting. We explore several modifications of the model in an attempt to
incorporate this physics in a natural way. At the qualitative level we find
that this constrains our choice to a picture in which the C=+/- splitting is
driven by mixing with new states built on closed loops of adjoint flux. However
a detailed numerical comparison suggests that a model incorporating an
additional direct mixing between loops of opposite orientation is likely to
work better; and that, in any case, a non-zero curvature term will be required.
We also point out that a characteristic of any string model of glueballs is
that the SU(N=infinity) mass spectrum will consist of multiple towers of states
that are scaled up copies of each other. To test this will require a lattice
mass spectrum that extends to somewhat larger masses than currently available.

</DOC>
<DOC>
<DOCNO> 121391 </DOCNO>
Photometric Constraints on Chemical Evolution Models of Irregular


  Photometric properties of stellar populations that evolve according to
chemical evolution models developed by Carigi, Colin, & Peimbert (1999) and
Carigi & Peimbert (2001) are explored. Models explain the oxygen abundance and
gas mass fraction of irregular galaxies NGC 1560, I Zw 18, NGC 2366, and a
typical irregular galaxy. The photometric predictions help to narrow down the
range of possible chemical evolution models. Observed colors of I Zw 18 imply
an age of 10^8 - 10^9 yr for its dominant population, while 10^9 - 10^{10} yr
is an older age preferred by the rest of the galaxy sample. Observed colors are
in general, within errors, close to predicted. There is a tendency for the
observed (B-V) color to imply higher metallicities at a fixed age than (U-B)
(equivalently, (U-B) implies younger ages than (B-V)).

</DOC>
<DOC>
<DOCNO> 70791 </DOCNO>
Solar neutrino results and Violation of the Equivalence Principle: An


  Violation of the Equivalence Principle (VEP) can lead to neutrino oscillation
through the non-diagonal coupling of neutrino flavor eigenstates with the
gravitational field. The neutrino energy dependence of this oscillation
probability is different from that of the usual mass-mixing neutrino
oscillations. In this work we explore, in detail, the viability of the VEP
hypothesis as a solution to the solar neutrino problem in a two generation
scenario with both the active and sterile neutrino alternatives, choosing these
states to be massless. To obtain the best-fit values of the oscillation
parameters we perform a chi square analysis for the total rates of solar
neutrinos seen at the Chlorine (Homestake), Gallium (Gallex and SAGE),
Kamiokande, and SuperKamiokande (SK) experiments. We find that the goodness of
these fits is never satisfactory. It markedly improves, especially for VEP
transformation to sterile neutrinos, if the Chlorine result is excluded from
the analysis. The 1117-day SK data for recoil electron spectrum are also
examined for signals of VEP oscillations. For these fits, we consider
variations of the Standard Solar Model by allowing the absolute normalizations
of the 8B and hep neutrinos to vary. Here the fits are quite good but the best
fit values of the parameters are rather different from those from the total
rates fits. A combined fit to the total rates and recoil electron spectrum data
is also performed. We present the 90% confidence limit contours for all the
three analyses mentioned above. The best-fit parameters obtained from the
recoil electron spectrum and the combined analysis of rate and spectrum are
used to predict the charge current and scattering electron spectrum at SNO.

</DOC>
<DOC>
<DOCNO> 13072 </DOCNO>
Paired fractional quantum Hall states and the nu=5/2 puzzle


  Work on the problem of the $\nu=5/2$ fractional quantum Hall state is
reviewed, with emphasis on recent progress concerning paired states.

</DOC>
<DOC>
<DOCNO> 150951 </DOCNO>
Reduction of the two-body dynamics to a one-body description in


  We discuss the mapping of the conservative part of two-body electrodynamics
onto that of a test charged particle moving in some external electromagnetic
field, taking into account recoil effects and relativistic corrections up to
second post-Coulombian order. Unlike the results recently obtained in general
relativity, we find that in classical electrodynamics it is not possible to
implement the matching without introducing external parameters in the effective
electromagnetic field. Relaxing the assumption that the effective test particle
moves in a flat spacetime provides a feasible way out.

</DOC>
<DOC>
<DOCNO> 69310 </DOCNO>
Effect of light sigma-meson Production in ppbar --> 3 pi0 at rest


  The pi0 pi0 mass spectra and angular distributions around KKbar -threshold
and at 1.5 GeV in ppbar (at rest) --> 3 pi0 in the Crystal Barrel experiment
are reanalyzed by applying the new method, which is consistent with unitarity
of S-matrix and expressed directly by resonance parameters. The effects of
light sigma-meson production are clearly seen to improve the fit with sigma, in
comparing with the fit without sigma.

</DOC>
<DOC>
<DOCNO> 122383 </DOCNO>
Petersen diagram for RRd stars in the Magellanic Clouds


  RRd stars from the Magellanic Clouds form a well-defined band in the Petersen
diagram. We explain this observed band with our evolutionary and pulsation
calculations with assumed metallicity [Fe/H]=(-2,-1.3). Vast majority of RRd
stars from LMC is confined to a narrower range of (-1.7,-1.3). The width of the
band, at specified fundamental mode period, may be explained by mass spread at
given metallicity. The shape of the band reflects the path of RRd stars within
the RR Lyrae instability strip. We regard the success in explaining the
Petersen diagram a support for our evolutionary models, which yield, mean
absolute magnitude in the mid of the instability strip, <M_V>, in the range 0.4
to 0.65 mag implying distance modulus to LMC of 18.4 mag.

</DOC>
<DOC>
<DOCNO> 122050 </DOCNO>
Periodic Photometric Variability in the Becklin-Neugebauer Object


  The Becklin-Neugebauer (BN) object in the Orion Nebula Cluster (ONC) is a
well-studied optically invisible, infrared-bright young stellar object, thought
to be an intermediate-mass protostar. We report here that BN exhibited
nearly-sinusoidal periodic variability at the near-infrared H- and Ks-bands
during a one month observing campaign in 2000 March/April. The period was 8.28
days and the peak-to-peak amplitude ~0.2 mag. Plausible mechanisms for
producing the observed variability characteristics are explored.

</DOC>
<DOC>
<DOCNO> 116782 </DOCNO>
Strong Discontinuities in the Complex Photonic Band Structure of


  Complex photonic band structures (CPBS) of transmission metallic gratings
with rectangular slits are shown to exhibit strong discontinuities that are not
evidenced in the usual energetic band structures. These discontinuities are
located on Wood's anomalies and reveal unambiguously two different types of
resonances, which are identified as horizontal and vertical surface-plasmon
resonances. Spectral position and width of peaks in the transmission spectrum
can be directly extracted from CPBS for both kinds of resonances.

</DOC>
<DOC>
<DOCNO> 68532 </DOCNO>
Probing flavor changing interactions in hadron collisions


  The subprocess $gg \to t\bar{c}+\bar{t}c$ in the two-Higgs-doublet model with
flavor-changing scalar couplings is examined at the one loop level. With
perturbative QCD factorization theorem, the corresponding cross sections for
hadron-hadron collisions are computed numerically. The results are applicable
to the whole mass range of the weakly coupled Higgs bosons. In case we could
efficiently exclude the severe backgrounds of the $t\bar{c}(\bar{t}c)$
production signal, probing the flavor-changing top-charm-scalar vertex at
hadron colliders would be very promising and accessible experimentally.

</DOC>
<DOC>
<DOCNO> 122501 </DOCNO>
The Magnificent Seven: Close-by Cooling Neutron Stars?


  We model Galactic populations of accreting and cooling isolated neutron stars
in the attempt to explore their link with a new class of dim soft X-ray sources
revealed by ROSAT. For accretors we follow the magneto-rotational and dynamical
evolution in the Galactic potential and a realistic large scale distribution of
the interstellar medium is used. Under standard assumptions old neutron stars
enter the accretor stage only if their magnetic field exceeds $\approx
10^{11}$--$10^{12}$ G. We predict about 1 source per square degree for fluxes
$\approx 10^{-15}$--$10^{-16}$ erg cm$^{-2}$s$^{-1}$ in the energy range 0.5-2
keV.
  Cooling neutron stars are explored within a simpler model of local sources,
including however interstellar absorption. They are found to be significantly
less abundant at low fluxes, $<0.1$ sources per square degree, but dominate
over accretors at higher flux levels ($\approx 10^{-12}$--$10^{-11}$ erg
cm$^{-2}$s$^{-1}$). We suggest that the faint sources observed by ROSAT may be
young cooling neutron stars with typical age $\la 10^6$ yrs, if the total
number of young neutron stars in the Solar proximity is $\sim 10$ times higher
than inferred from radiopulsars statistics.

</DOC>
<DOC>
<DOCNO> 151242 </DOCNO>
Large-N expansion, conformal field theory and renormalization-group


  I study a class of interacting conformal field theories and conformal windows
in three dimensions, formulated using the Parisi large-N approach and a
modified dimensional-regularization technique. Bosons are associated with
composite operators and their propagators are dynamically generated by fermion
bubbles. Renormalization-group flows between pairs of interacting fixed points
satisfy a set of non-perturbative g <-> 1/g dualities. There is an exact
relation between the beta function and the anomalous dimension of the composite
boson. Non-Abelian gauge fields have a non-renormalized and quantized gauge
coupling, although no Chern-Simons term is present. A problem of the naive
dimensional-regularization technique for these theories is uncovered and
removed with a non-local, evanescent, non-renormalized kinetic term. The models
are expected to be a fruitful arena for the study of odd-dimensional conformal
field theory.

</DOC>
<DOC>
<DOCNO> 100903 </DOCNO>
Baxter T-Q Equation for Shape Invariant Potentials. The Finite-Gap


  The Darboux transformation applied recurrently on a Schroedinger operator
generates what is called a {\em dressing chain}, or from a different point of
view, a set of supersymmetric shape invariant potentials. The finite-gap
potential theory is a special case of the chain. For the finite-gap case, the
equations of the chain can be expressed as a time evolution of a Hamiltonian
system. We apply Sklyanin's method of separation of variables to the chain. We
show that the classical equation of the separation of variables is the Baxter
T-Q relation after quantization.

</DOC>
<DOC>
<DOCNO> 121074 </DOCNO>
The Solar Helium Abundance in the Outer Corona Determined from


  At altitudes of about 1.05 solar radii or more, the corona above quiet solar
regions becomes essentially isothermal. This obviates many of the difficulties
associated with the inverse problem of determining emission measure
distributions, and allows for fairly straightforward relative element abundance
measurements. We present new values for the He abundance. The first is based on
a reanalysis of the He/O ratio studied previously using data acquired by SUMER.
A more thorough evaluation of the atomic physics for He II, including a
detailed treatment of radiative recombination, increases the predicted emission
in the He II Balmer series compared to earlier analyses. We use a recently
revised value of the O abundance to derive an He/H abundance ratio of 0.038,
(mass fraction, Y=0.13), with an error of ~17% coming mainly from the O
abundance uncertainty. We demonstrate that this result may be affected by
gravitational settling of O relative to He. We also derive an abundance for He
by direct comparison to emission lines of the H I Lyman series, with the result
He/H =0.052 +/- 0.005 (Y=0.17), a value similar to He abundances determined in
the slow speed solar wind.

</DOC>
<DOC>
<DOCNO> 67646 </DOCNO>
Possible Test of the GUT Relation between $M_1$ and $M_2$ in


  We investigate associated production of selectrons and the lightest
neutralino (LSP) in the process e^- + gamma --> neutralino_1 + selectron_{L/R}
with the selectron subsequently decaying into an electron and the LSP. Total
cross sections and various polarization asymmetries are calculated for photons
produced by Compton backscattering of a polarized laser beam at an $e^+e^-$
linear collider with CMS energy $\sqrt{s_{ee}}=500$ GeV and with polarized
beams. The total cross section and in particular the polarization asymmetries
show a characteristic dependence on the gaugino mass parameter $M_1$. Therefore
this process is suitable for testing the GUT relation
$M_1=M_2\cdot{5/3}\tan^2\theta_W $.

</DOC>
<DOC>
<DOCNO> 116754 </DOCNO>
The use of GPS-arrays in detecting shock-acoustic waves generated during


  This paper is concerned with the form and dynamics of shock-acoustic waves
(SAW) generated during rocket launchings. We have developed a method for
determining SAW parameters (including angular characteristics of the wave
vector, and the SAW phase velocity, as well as the direction towards the
source) using GPS-arrays whose elements can be chosen out of a large set of
GPS-stations of the global GPS network. The application of the method is
illustrated by a case study of ionospheric effects from launchings of launch
vehicles (LV) Proton and Space Shuttle from space-launch complexes Baikonur and
Kennedy Space Center (KSC) in 1998 and 1999 (a total of five launchings). The
study revealed that, in spite of a difference of LV characteristics, the
ionospheric response for all launchings had the character of an N - wave
corresponding to the form of a shock wave, regardless of the disturbance source
(rocket launchings, industrial explosions). The SAW period T is 270--360 s, and
the amplitude exceeds the standard deviation of TEC background fluctuations in
this range of periods under quiet and moderate geomagnetic conditions by
factors of 2 to 5 as a minimum. The angle of elevation of the SAW wave vector
varies from 30 degree to 60 degree, and the SAW phase velocity (900-1200 m/s)
approaches the sound velocity at heights of the ionospheric F-region maximum.

</DOC>
<DOC>
<DOCNO> 152477 </DOCNO>
Localization of Bulk Fields on AdS_4 Brane in AdS_5


  We study the localization of various bulk fields on an $AdS_4$ brane in
$AdS_5$. In this case, for a small brane cosmological constant, all the bulk
fields ranging from scalar to graviton are naturally confined to the brane only
through the gravitational interaction. In particular, for the vector field we
can find an interesting zero mode solution which satisfies the box boundary
condition. In the cases of spin 1/2 spinor and 3/2 gravitino fields, the form
of zero modes is very similar to as in a flat Minkowski brane, but they are
trapped on the $AdS_4$ brane even without introducing a mass term with a 'kink'
profile.

</DOC>
<DOC>
<DOCNO> 70006 </DOCNO>
Transverse Lattice


  The transverse lattice approach to non-perturbative light-front hamiltonian
QCD is described. Preliminary results on the pi-rho system are presented, at
fixed DLCQ and Tamm-Dancoff cut-offs. A renormalised, approximately Lorentz
covariant light-front hamiltonian is found to leading order of the
colour-dielectric expansion, compatible with a massless pion. The pi
light-front wavefunction is compared with experiment. Exclusive processes agree
reasonably well, given the approximations, but inclusive processes, sensitive
to higher Fock state structure, still exhibit large cut-off artifacts.

</DOC>
<DOC>
<DOCNO> 71999 </DOCNO>
Diquarks and Density


  We describe aspects of the role that diquark correlations play in
understanding baryon structure and interactions. The significance of diquarks
in that application motivates a study of the possibility that dense hadronic
matter may exhibit diquark condensation; i.e., quark-quark pairing promoted by
a quark chemical potential. A Gorkov-Nambu-like gap equation is introduced for
QCD and analysed for 2-colour QCD (QC2D) and, in two qualitatively different
truncations, for QCD itself. Among other interesting features, we illustrate
that QC2D with massive fermions undergoes a second-order transition to a
superfluid phase when the chemical potential exceeds 0.5 m.pi. In the QCD
application we illustrate that the sigma= <bar-q q> .neq. 0 phase, which
determines the properties of the mass spectrum at zero temperature and chemical
potential, is unstable with respect to the superfluid phase when the chemical
potential exceeds approx. 2 sigma, and that at this point the diquark gap is
large, approx. 0.5 sigma. The superfluid phase survives to temperatures greater
than that expected in the core of compact stars.

</DOC>
<DOC>
<DOCNO> 150571 </DOCNO>
More on counterterms in the gravitational action and anomalies


  The addition of boundary counterterms to the gravitational action of
asymptotically anti-de Sitter spacetimes permits us to define the partition
function unambiguously without background subtraction. We show that the
inclusion of p-form fields in the gravitational action requires the addition of
further counterterms which we explicitly identify. We also relate logarithmic
divergences in the action dependent on the matter fields to anomalies in the
dual conformal field theories. In particular we find that the anomaly predicted
for the correlator of the stress energy tensor and two vector currents in four
dimensions agrees with that of the ${\cal{N}} = 4$ superconformal SU(N) gauge
theory.

</DOC>
<DOC>
<DOCNO> 10930 </DOCNO>
Spin-Polarized Transport Across an


  Transport across an
La$_{0.7}$Sr$_{0.3}MnO$_{3}/YBa$_{2}Cu$_{3}$O$_{7}$(LSMO/YBCO), interface is
studied as a function of temperature and surface morphology. For comparison,
control measurements are performed in non-magnetic heterostructures of
LaNiO$_{3}$/YBCO and Ag/YBCO. In all cases, YBCO is used as bottom layer to
eliminate the channel resistance and to minimize thermal effects. The observed
differential conductance re ects the role of Andreev bound states in a-b
planes, and brings out for the first time the suppression of such states by the
spin-polarized transport across the interface. The theoretical analysis of the
measured data reveals decay of the spin polarization near the LSMO surface with
temperature, consistent with the reported photoemission data.

</DOC>
<DOC>
<DOCNO> 40002 </DOCNO>
Measurement of the K_L -> e+ e- e+ e- Decay Rate


  The decay rate of the neutral long-lived K meson into the e+ e- e+ e- final
state has been measured with the NA48 detector at the CERN SPS. Using data
collected in 1999, a total of 132 events has been observed with negligible
background. The total number of kaons was determined to be 5.1 x 10^10. This
observation corresponds to a preliminary branching ratio of Gamma(K_L -> e+ e-
e+ e-)/Gamma(K_L -> all) = (3.67 +- 0.32(stat) +- 0.23(sys) +- 0.08(norm)) x
10^-8, where the first error is statistical, the second systematic, and the
third error is due to the uncertainty in the normalization.

</DOC>
<DOC>
<DOCNO> 12444 </DOCNO>
Critical behavior of ferromagnetic spin models with aperiodic exchange


  We review recent investigations of the critical behavior of ferromagnetic
$q$-state Potts models on a class of hierarchical lattices, with exchange
interactions according to some deterministic but aperiodic substitution rules.
The problem is formulated in terms of exact recursion relations on a suitable
parameter space. The analysis of the fixed points of these equations leads to a
criterion to gauge the relevance of the aperiodic geometric fluctuations. For
irrelevant fluctuations, the critical behavior remains unchanged with respect
to the underlying uniform models. In the presence of relevant fluctuations, a
non-trivial symmetric fixed point, associated with the critical behavior of the
uniform model, becomes fully unstable, and there appears a two-cycle of the
recursion relations. A scaling analysis, supported by direct numerical
thermodynamical calculations, shows the existence of a novel critical
universality class associated with relevant geometric fluctuations.

</DOC>
<DOC>
<DOCNO> 68026 </DOCNO>
The Origin of Cosmic Magnetic Fields


  In this talk, I review a number of particle-physics models that lead to the
creation of magnetic fields in the early universe and address the complex
problem of evolving such primordial magnetic fields into the fields observed
today. Implications for future observations of the Cosmic Microwave Background
(CMB) are discussed. Focussing on first-order phase transitions in the early
universe, I describe how magnetic fields arise in the collision of expanding
true-vacuum bubbles both in Abelian and non-Abelian gauge theories.

</DOC>
<DOC>
<DOCNO> 99651 </DOCNO>
A Note on the Symmetric Powers of the Standard Representation of S_n


  In this paper, we prove that the dimension of the space spanned by the
characters of the symmetric powers of the standard n-dimensional representation
of the symmetric group S_n is asymptotic to n^2/2. This is proved by using
generating functions to obtain formulas for upper and lower bounds, both
asymptotic to n^2/2, for this dimension. In particular, for n>6, these
characters do not span the full space of class functions on S_n.

</DOC>
<DOC>
<DOCNO> 151699 </DOCNO>
Open strings, 2D gravity and AdS/CFT correspondence


  We present a detailed discussion of the duality between dilaton gravity on
AdS_2 and open strings. The correspondence between the two theories is
established using their symmetries and field theoretical, thermodynamic, and
statistical arguments. We use the dual conformal field theory to describe
two-dimensional black holes. In particular, all the semiclassical features of
the black holes, including the entropy, have a natural interpretation in terms
of the dual microscopic conformal dynamics. The previous results are discussed
in the general framework of the Anti-de Sitter/Conformal Field Theory
dualities.

</DOC>
<DOC>
<DOCNO> 12951 </DOCNO>
Magnetic field dependence of the energy of negatively charged excitons


  A variational calculation of the spin-singlet and spin-triplet state of a
negatively charged exciton (trion) confined to a single quantum well and in the
presence of a perpendicular magnetic field is presented. We calculated the
probability density and the pair correlation function of the singlet and
triplet trion states. The dependence of the energy levels and of the binding
energy on the well width and on the magnetic field strength was investigated.
We compared our results with the available experimental data on GaAs/AlGaAs
quantum wells and find that in the low magnetic field region (B<18 T) the
observed transition are those of the singlet and the dark triplet trion (with
angular momentum $L_z=-1$), while for high magnetic fields (B>25 T) the dark
trion becomes optically inactive and possibly a transition to a bright triplet
trion (angular momentum $L_z=0$) state is observed.

</DOC>
<DOC>
<DOCNO> 99329 </DOCNO>
Gauge Orbit Types for Generalized Connections


  Different versions for defining Ashtekar's generalized connections are
investigated depending on the chosen smoothness category for the paths and
graphs -- the label set for the projective limit. Our definition covers the
analytic case as well as the case of webs.
  Then the orbit types of the generalized connections are determined for
compact structure groups. The stabilizer of a connection is homeomorphic to the
holonomy centralizer, i.e. the centralizer of its holonomy group, and the
homeomorphism class of the gauge orbit is completely determined by the holonomy
centralizer. Furthermore, the stabilizers of two connections are conjugate in
the gauge group if and only if their holonomy centralizers are conjugate in the
structure group. Finally, the gauge orbit type of a connection is defined to be
the conjugacy class of its holonomy centralizer equivalently to the standard
definition via stabilizers.

</DOC>
<DOC>
<DOCNO> 9420 </DOCNO>
Trading behavior and excess volatility in toy markets


  We study the relation between the trading behavior of agents and volatility
in toy markets of adaptive inductively rational agents. We show that excess
volatility, in such simplified markets, arises as a consequence of {\em i)} the
neglect of market impact implicit in price taking behavior and of {\em ii)}
excessive reactivity of agents. These issues are dealt with in detail in the
simple case without public information. We also derive, for the general case,
the critical learning rate above which trading behavior leads to turbulent
dynamics of the market.

</DOC>
<DOC>
<DOCNO> 80915 </DOCNO>
Can One Study Heavy Meson Semileptonic Decays on Coarse Anisotropic


  Exploratory studies of heavy meson semileptonic decays on coarse lattices
using Symanzik improved glue, NRQCD heavy and D234 light quarks are discussed.
Comparisons are made between calculations on anisotropic and isotropic
lattices. We find evidence that having an anisotropy helps in extracting better
signals at higher momenta.

</DOC>
<DOC>
<DOCNO> 179055 </DOCNO>
Signatures of the quark gluon plasma: a personal overview


  We first discuss, on a no-QGP basis, the two prominent indications of (a)
enhanced strangeness production and of (b) anomalous $J/\psi $-suppression: We
elaborate in particular on a recent idea of antihyperon production solely by
multi-mesonic reactions. As a possible source for an enhanced dissociation of
$c \bar{c}$ pairs we summarize the findings within the 'early'-comover
absorption scenario of prehadronic string excitations. As an exotic candidate
we then finally adress the stochastic formation of so called disoriented chiral
condensates: An experimentally feasible DCC, if it does exist, has to be a rare
event following an unusual and nontrivial distribution on an event by event
basis.

</DOC>
<DOC>
<DOCNO> 71904 </DOCNO>
Study of $\Lambda_b\to\Lambda\nu\bar{\nu}$ with Polarized Baryons


  We investigate the decay of $\Lambda_b\to\Lambda\nu\bar{\nu}$ with the
polarized baryons of $\Lambda_b$ and $\Lambda$. With the most general hadronic
form factors, we first study the decay branching ratio and then derive the
longitudinal, normal and transverse polarizations of $\Lambda$ in terms of the
spin unit vectors of $\Lambda_b$ and $\Lambda $ and the momentum of $\Lambda $.
A polarization of $\Lambda_b$ is also discussed.

</DOC>
<DOC>
<DOCNO> 121628 </DOCNO>
On the Hardness-Intensity Correlation in Gamma-Ray Burst Pulses


  We study the hardness-intensity correlation (HIC) in gamma-ray bursts (GRBs).
In particular, we analyze the decay phase of pulse structures in their light
curves. The study comprises a sample of 82 long pulses selected from 66 long
bursts observed by BATSE on the Compton Gamma-Ray Observatory. We find that at
least 57% of these pulses have HICs that can be well described by a power law.
The distribution of the power law indices, obtained by modeling the HIC of
pulses from different bursts, is broad with a mean of 1.9 and a standard
deviation of 0.7. We also compare indices among pulses from the same bursts and
find that their distribution is significantly narrower. The probability of a
random coincidence is shown to be very small. In most cases, the indices are
equal to within the uncertainties. This is particularly relevant when comparing
the external versus the internal shock models. In our analysis, we also use a
new method for studying the HIC, in which the intensity is represented by the
peak value of the E F_E spectrum. This new method gives stronger correlations
and is useful in the study of various aspects of the HIC. In particular, it
produces a better agreement between indices of different pulses within the same
burst. Also, we find that some pulses exhibit a "track jump" in their HICs, in
which the correlation jumps between two power laws with the same index. We
discuss the possibility that the "track jump" is caused by strongly overlapping
pulses. Based on our findings, the constancy of the index is proposed to be
used as a tool for pulse identification in overlapping pulses.

</DOC>
<DOC>
<DOCNO> 9160 </DOCNO>
Reorientation of Anisotropy in a Square Well Quantum Hall Sample


  We have measured magnetotransport at half-filled high Landau levels in a
quantum well with two occupied electric subbands. We find resistivities that
are {\em isotropic} in perpendicular magnetic field but become strongly {\em
anisotropic} at $\nu$ = 9/2 and 11/2 on tilting the field. The anisotropy
appears at an in-plane field, $B_{ip} \sim$ 2.5T, with the easy-current
direction {\em parallel} to $B_{ip}$ but rotates by 90$^{\circ}$ at $B_{ip}
\sim$ 10T and points now in the same direction as in single-subband samples.
This complex behavior is in quantitative agreement with theoretical
calculations based on a unidirectional charge density wave state model.

</DOC>
<DOC>
<DOCNO> 7979 </DOCNO>
Duality relations for M coupled Potts models


  We establish explicit duality transformations for systems of M q-state Potts
models coupled through their local energy density, generalising known results
for M=1,2,3. The M-dimensional space of coupling constants contains a selfdual
sub-manifold of dimension D_M = [M/2].
 For the case M=4, the variation of the effective central charge along the
selfdual surface is investigated by numerical transfer matrix techniques.
Evidence is given for the existence of a family of critical points,
corresponding to conformal field theories with an extended S_M symmetry
algebra.

</DOC>
<DOC>
<DOCNO> 102374 </DOCNO>
Arbres de Hurwitz et automorphismes d'ordre p des disques et des


  Let R be a complete discrete valuation ring of mixed characteristics (0,p).
Given an order p-automorphism of a formal disc (or annulus) over R, we describe
the minimal semi-stable model for which the specialisations of fixed points are
distincts and lie in the smooth locus of the special fiber. The description
leads to a combinatorial object called Hurwitz tree. Our main result is a
necessary and sufficient condition for a Hurwitz tree to arise from an order
p-automorphism.

</DOC>
<DOC>
<DOCNO> 123144 </DOCNO>
The Luminosity Function Of Field Galaxies And Its Evolution Since z=1


  We present the B-band luminosity function and comoving space and luminosity
densities for a sample of 2779 I-band selected field galaxies based on
multi-color data from the CADIS survey. The sample is complete down to I_815 =
22 without correction and with completeness correction extends to I_815=23.0.
By means of a new multi-color analysis the objects are classified according to
their spectral energy distributions (SEDs) and their redshifts are determined
with typical errors of delta z <= 0.03. We have split our sample into four
redshift bins between z=0.1 and z=1.04 and into three SED bins E-Sa,Sa-Sc and
starbursting (emission line) galaxies. The evolution of the luminosity function
is clearly differential with SED. The normalization phi* of luminosity function
for the E-Sa galaxies decreases towards higher redshift, and we find evidence
that the comoving galaxy space density decreases with redshift as well. In
contrast, we find phi* and the comoving space density increasing with redshift
for the Sa-Sc galaxies. For the starburst galaxies we find a steepening of the
luminosity function at the faint end and their comoving space density increases
with redshift.

</DOC>
<DOC>
<DOCNO> 71947 </DOCNO>
Majorana Neutrino Masses and Neutrino Oscillations


  We examine some patterns of Majorana neutrino mass matrix which is compatible
with the phenomenological lepton flavor mixing matrix and non-observation of
neutrinoless double beta decay. Imposing $(M_{\nu})_{ee}=0$ for the Majorana
neutrino mass matrix in the leading order, we obtain a relationship between the
solar mixing angle and the neutrino masses $m_1$ and $m_2$. Additional possible
texture zeros are assigned to the mass matrix so as for the nonvanishing
$\theta_{13}$ to be predictable in terms of neutrino masses. We also show how
three neutrino masses can be predicted from the solar mixing angle and the
experimental results of $\Delta m^2_{sol}$ and $\Delta m^2_{atm}$ in this
framework, and we discuss naturality of the forms of the mass matrix found in
our work.

</DOC>
<DOC>
<DOCNO> 119900 </DOCNO>
M87 at 90cm: A Different Picture


  We report new radio imaging of the large scale radio structure of M87 with
the VLA at 90 cm. These new images show the complex structure of the radio
emission more clearly than previous attempts, some of which date back to the
1940's. The images suggest that the outward flow from the M87 nucleus extends
well beyond the 2 kpc jet. Two ``bubbles'' of synchrotron emission appear to be
inflated by this flow. A simple model of the emission, combined with our
knowledge of the inner jet, suggests that the energy input into this region
from the M87 nucleus exceeds the energy being radiated away as X-rays. This
argues that the region within 40 kpc of the center of M87 is currently
dominated by energy input from the M87 nucleus. The gas in the region is
expanding, not flowing inward as is envisioned in the cooling flow model.

</DOC>
<DOC>
<DOCNO> 68498 </DOCNO>
Large CP Violation, Large Mixings of Neutrinos and the $Z_3$ Symmetry


  We present neutrino mass matrices which predict the atmospheric neutrino
mixing to be almost maximal, $\sin^2 2\theta_{atm}>0.999$, as well as the large
solar neutrino mixing, $8/9>\sin^2 2\theta_{sol}>0.87$, and the large CP
violation (the CP violation phase in the standard form is maximal
$\delta=\pi/2$), based on the $Z_3$ symmetry.

</DOC>
<DOC>
<DOCNO> 178673 </DOCNO>
The Role of Ground State Correlations in the Single-Particle Strength of


  A method based on the consistent use of the Green function formalism has been
developed to calculate the distribution of the single-particle strength in odd
nuclei with pairing. The method takes into account the quasiparticle-phonon
interaction, ground state correlations and a "refinement" of phenomenological
single-particle energies and pairing gap values from the quasiparticle-phonon
interaction under consideration. The calculations for 121Sn and 119Sn that were
performed in the quasiparticle$\otimes$phonon approximation, have shown a
reasonable agreement with experiment. The ground state correlations play a
noticeable role and mostly improve the agreement with experiment or shift the
results to the right direction.

</DOC>
<DOC>
<DOCNO> 11965 </DOCNO>
Metal-insulator transition in a 2D electron gas: Equivalence of two


  The critical electron density for the metal-insulator transition in a
two-dimensional electron gas can be determined by two distinct methods: (i) a
sign change of the temperature derivative of the resistance, and (ii) vanishing
activation energy and vanishing nonlinearity of current-voltage characteristics
as extrapolated from the insulating side. We find that in zero magnetic field
(but not in the presence of a parallel magnetic field), both methods give
equivalent results, adding support to the existence of a true zero-field
metal-insulator transition.

</DOC>
<DOC>
<DOCNO> 9162 </DOCNO>
Analysis on Aging in the Generalized Random Energy Model


  A new dynamics more natural than that proposed by Bouchaud and Dean is
introduced to the Generalized Random Energy Model, and the master equation for
the dynamics is solved exactly to calculate the time correlation function.
Although our results are very similar to those obtained by Bouchaud and Dean
qualitatively, the exponents for power law relaxation are different. The
Zero-Field-Cooled magnetization is also calculated with a relation between the
correlation function and the response function which holds even if the
relaxation is non-equilibrium. The validity of these analytic results are
confirmed by numerical simulations.

</DOC>
<DOC>
<DOCNO> 12257 </DOCNO>
Quantum Criticality: competing ground states in low dimensions


  Small changes in an external parameter can often lead to dramatic qualitative
changes in the lowest energy quantum mechanical ground state of a correlated
electron system. In anisotropic crystals, such as the high temperature
superconductors where electron motion occurs primarily on a two-dimensional
square lattice, the quantum critical point between two such lowest energy
states has non-trivial emergent excitations which control the physics over a
significant portion of the phase diagram. Non-zero temperature dynamic
properties near quantum critical points are described using simple theoretical
models. Possible quantum phases and transitions of the two-dimensional electron
gas on a square lattice are discussed, including phases with spin-charge
separation and their experimental signatures.

</DOC>
<DOC>
<DOCNO> 7993 </DOCNO>
Observation of strong surface state effects in the nonlinear


  Spectroscopic magnetization induced optical Second Harmonic Generation (MSHG)
measurements from a clean Ni(110) surface reveal strong resonance effects near
2.7 eV that can be attributed to the presence of an empty surface state. The
good agreement with model calculations shows the potential of MSHG to probe
spin polarized interface band structures.

</DOC>
<DOC>
<DOCNO> 102190 </DOCNO>
A Particle Field Theorist's Lectures on Supersymmetric, Non-Abelian


  This monograph is derived from a series of six lectures I gave at the Centre
de Recherches Mathematiques in Montreal, in March and June 2000, while titulary
of the Aisenstadt Chair.

</DOC>
<DOC>
<DOCNO> 178463 </DOCNO>
Quantum Monte Carlo calculations of six-quark states


  The variational Monte Carlo method is used to find the ground state of six
quarks confined to a cavity of diameter R_c, interacting via an assumed
non-relativistic constituent quark model (CQM) Hamiltonian. We use a flux-tube
model augmented with one-gluon and one-pion exchange interactions, which has
been successful in describing single hadron spectra. The variational wave
function is written as a product of three-quark nucleon states with
correlations between quarks in different nucleons. We study the role of quark
exchange effects by allowing flux-tube configuration mixing. An accurate
six-body variational wave function is obtained. It has only ~13% rms
fluctuation in the total energy and yields a standard deviation of ~<.1%; small
enough to be useful in discerning nuclear interaction effects from the large
rest mass of the two nucleons. Results are presented for three values of the
cavity diameter, R_c=2, 4, and 6 fm. They indicate that the flux-tube model
Hamiltonian with gluon and pion exchange requires revisions in order to obtain
agreement with the energies estimated from realistic two-nucleon interactions.
We calculate the two-quark probability distribution functions and show how they
may be used to study and adjust the model Hamiltonian.

</DOC>
<DOC>
<DOCNO> 84433 </DOCNO>
Numerical hydrodynamics in general relativity


  The current status of numerical solutions for the equations of ideal general
relativistic hydrodynamics is reviewed. Different formulations of the equations
are presented, with special mention of conservative and hyperbolic formulations
well-adapted to advanced numerical methods. A representative sample of
available numerical schemes is discussed and particular emphasis is paid to
solution procedures based on schemes exploiting the characteristic structure of
the equations through linearized Riemann solvers. A comprehensive summary of
relevant astrophysical simulations in strong gravitational fields, including
gravitational collapse, accretion onto black holes and evolution of neutron
stars, is also presented.

</DOC>
<DOC>
<DOCNO> 80817 </DOCNO>
Vortices in $SO(3)\times Z(2)$ simulations


  We explore simulations on periodic lattices in the Tomboulis $SO(3)\times
Z(2)$ formulation. The dynamical variables are constrained. We propose an
update algorithm that satisfies the constraints and is straightforward to
implement. We show how boundary conditions put constraints on the configuration
space.

</DOC>
<DOC>
<DOCNO> 11644 </DOCNO>
Quantum Monte Carlo Analysis of Exchange and Correlation in the Strongly


  We use variational quantum Monte Carlo to calculate the density-functional
exchange-correlation hole n_{xc}, the exchange-correlation energy density
e_{xc}, and the total exchange-correlation energy E_{xc}, of several electron
gas systems in which strong density inhomogeneities are induced by a
cosine-wave potential. We compare our results with the local density
approximation and the generalized gradient approximation. It is found that the
nonlocal contributions to e_{xc} contain an energetically significant
component, the magnitude, shape, and sign of which are controlled by the
Laplacian of the electron density.

</DOC>
<DOC>
<DOCNO> 119064 </DOCNO>
Light Curves of Rapidly Rotating Neutron Stars


  We consider the effect of rapid rotation on the light curves of neutron stars
with hot polar caps. For $P \approx 3$ms spin periods, the pulse fractions can
be as much as an order of magnitude larger than with simple slowly-rotating
(Schwarzschild) estimates. Doppler boosting, in particular, leads to
characteristic distortion and ``soft lags'' in the pulse profiles, which are
easily measurable in light curves with moderate energy resolution. With $\sim
10^5$ photons it should also be possible to isolate the more subtle distortions
of light travel time variations and frame dragging. Detailed analysis of high
quality millisecond pulsar data from upcoming X-ray missions must include these
effects.

</DOC>
<DOC>
<DOCNO> 13219 </DOCNO>
Vortex Softening: Origin of the second peak effect in


  Transverse ac permeability measurements in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta
}$ single crystals at low fields and temperatures in a vortex configuration
free of external forces show that the decrease of the critical current as
measured by magnetization loops at the second peak effect is an artifact due to
creep. On the other hand, the increase of critical current at the second peak
is due to a genuine softening of the tilting elastic properties of vortices in
the individual pinning regime that precedes the transition to a disorder state.

</DOC>
<DOC>
<DOCNO> 152433 </DOCNO>
Gravity in Two Spacetime Dimensions


  In this habilitation thesis we provide an introduction to gravitational
models in two spacetime dimensions. Focus is put on exactly solvable models. We
begin by introducing and motivating different possible gravitational actions,
including those of generalized dilaton theories as well as of purely
geometrical, higher derivative theories with and without torsion. The relation
among them as well as to Poisson sigma models is worked out in some detail. In
the exactly solvable cases, such as pure gravity-Yang-Mills systems, the
general solution to the field equations on a global level is reviewed.
Quantization of such models is performed in the Dirac approach, where, by use
of the formulation as Poisson sigma models, all admissible physical quantum
states are obtained.
  Table of contents: 1. Introduction, 2. 2d geometry and gravitational actions,
3. Generalized dilaton theories and matter actions, 4. 2d gravity-Yang-Mills
systems in terms of Poisson sigma models, 5. Classical solutions on a local
level, 6. Classical solutions on a global level, 7. Towards quantum gravity.
  (In part this work contains/summarizes previous joint work with T. Kloesch
and P. Schaller).

</DOC>
<DOC>
<DOCNO> 119983 </DOCNO>
Eclipsing Binaries in the OGLE Variable Star Catalogs.V. Long-Period


  Thirty eight long-period (P>10 days), apparently contact binary stars
discovered by the OGLE-II project in the SMC appear to be Beta Lyrae-type
systems with ellipsoidal variations of the cool components dominating over
eclipse effects in the systemic light variations and in the total luminosity. A
new period-luminosity- color (PLC) relation has been established for these
systems; we call it the PLC-beta relation, to distinguish it from the Cepheid
relation. Two versions of the PLC-beta relation - based on the (B-V)0 or (V-I)0
color indices - have been calibrated for 33 systems with (V-I)0>0.25 spanning
the orbital period range of 11 to 181 days. The relations can provide
maximum-light, absolute-magnitude estimates accurate to epsilon-M_V~0.35 mag.
within the approximate range -3<M_V<+1. In terms of their number in the SMC,
the long-period Beta Lyrae-type binaries are about 50 times less common than
the Cepheids. Nevertheless, their large luminosities coupled with continuous
light variations make these binaries very easy to spot in nearby galaxies, so
that the PLC-beta relation can offer an auxiliary and entirely independent
method of distance determination to nearby stellar systems rich in massive
stars. The sample of the long-period Beta Lyrae systems in the SMC analyzed in
this paper is currently the best defined and uniform known sequence of such
binaries.

</DOC>
<DOC>
<DOCNO> 12510 </DOCNO>
Exact solution of a reaction-diffusion process with three-site


  The one-dimensional reaction diffusion process AA->A and A0A->AAA is exactly
solvable through the empty interval method if the diffusion rate equals the
coagulation rate. Independently of the particle production rate, the model is
always in the universality class of diffusion-annihilation. This allows us to
check analytically the universality of finite-size scaling in a non-equilibrium
critical point.

</DOC>
<DOC>
<DOCNO> 9288 </DOCNO>
Pinhole model for the Josephson pi state in 3He


  This Master's Thesis presents some new quasiclassical calculations of the
Josephson pi state in 3He-B weak links.

</DOC>
<DOC>
<DOCNO> 84355 </DOCNO>
Darkholes: Nicer than blackholes - with a bright side, too (Does energy


  The geometry of three-dimensional space guides the search for a better model
than the blackhole with its unwelcome singularity. An elementary construction
produces on the 4-manifold of 2-spheres in a Riemannian 3-space a space-time
metric invariant under uniform conformal transformations of the 3-space. When
the 3-space is Euclidean, the metric reduces to de Sitter's expanding universe
metric. Generalization yields a space-time metric that retains the `exponential
expansion property' of the de Sitter metric. A strictly geometric action
principle gives field equations which, because they do not adhere to Einstein's
early confounding of energy and inertial mass with gravitating mass, admit
solutions that escape the Penrose-Hawking singularity theorems. A spherically
symmetric solution that is asymptotic to the Schwarzschild blackhole metric
has, in place of a horizon and a singularity, an Einstein-Rosen `bridge', or
`tunnel', connecting two asymptotically Euclidean regions. On one side the
gravitational center attracts, and is dark but not black; on the other side it
repels, and is bright. Travel and signaling from either side to the other via
the tunnel are possible. Analysis of the Einstein tensor of this `darkhole' (or
`darkhole-brighthole') suggests that not all energy produces gravity, and that
calling energy `negative', or its relationship to geometry `exotic', is
unjustified.

</DOC>
<DOC>
<DOCNO> 68010 </DOCNO>
Death of Stellar Baryonic Dark Matter


  The nature of the dark matter in the haloes of galaxies is one of the
outstanding questions in astrophysics. All stellar candidates, until recently
thought to be likely baryonic contributions to the Halo of our Galaxy, are
shown to be ruled out. Faint stars and brown dwarfs are found to constitute
only a few percent of the mass of the Galaxy. Stellar remnants, including white
dwarfs and neutron stars, are shown to be very constrained as well. High energy
gamma-rays observed in HEGRA data place the strongest constraints, $\Omega_{WD}
< 3 \times 10^{-3} h^{-1}$, where $h$ is the Hubble constant in units of 100 km
s$^{-1}$ Mpc$^{-1}$. Hence one is left with several unanswered questions: 1)
What are MACHOs seen in microlensing surveys? 2) What is the dark matter in our
Galaxy? Indeed a nonbaryonic component in the Halo seems to be required.

</DOC>
<DOC>
<DOCNO> 69353 </DOCNO>
Sneutrino-Higgs mixing in WW and ZZ production in supersymmetry with


  We consider new s-channel scalar exchanges in e+e- -> ZZ,W+W- in
supersymmetry with a small lepton number violation. We show that a small
bilinear R-parity violating term which leads to sneutrino--Higgs mixing can
give rise to a significant scalar resonance enhancement in e+e- -> ZZ,W+W-. We
use the LEP2 measurements of the WW and ZZ cross-sections to place useful
constraints on this scenario. We also find, under conservative assumptions on
the relevant parameter space involved, that such an exchange of the
sneutrino-like admixture in e+e- -> ZZ,W+W- may be accessible to a 500 GeV e+e-
collider.

</DOC>
<DOC>
<DOCNO> 71869 </DOCNO>
Neutrino Masses and Mixing in Brane-World Theories


  We present a comprehensive study of five-dimensional brane-world models for
neutrino physics based on flat compactifications. Particular emphasis is put on
the inclusion of bulk mass terms. We derive a number of general results for
such brane-world models with bulk mass terms. In particular, in the limit of
small brane-bulk couplings, the electroweak eigenstates are predominantly given
as a superposition of three light states with non-trivial small admixtures of
bulk states. As a consequence, neutrinos can undergo standard oscillations as
well as oscillation into bulk Kaluza-Klein states. We use this structure to
construct a specific model based on Z_2 orbifolding and bulk Majorana masses
which is compatible with all observed oscillation phenomena. The solar neutrino
deficit is explained by oscillations into sterile bulk states while the
atmospheric neutrino deficit is due to mu - tau oscillations with naturally
maximal mixing. In addition, the model can accommodate the LSND result and a
significant neutrino dark matter component. We also analyze the constraints
from supernova energy loss on neutrino brane-world theories and show that our
specific model is consistent with these constraints.

</DOC>
<DOC>
<DOCNO> 102417 </DOCNO>
Bound states in weakly deformed strips and layers


  We consider Dirichlet Laplacians on straight strips in R^2 or layers in R^3
with a weak local deformation. First we generalize a result of Bulla et al. to
the three-dimensional situation showing that weakly coupled bound states exist
if the volume change induced by the deformation is positive; we also derive the
leading order of the weak-coupling asymptotics. With the knowledge of the
eigenvalue analytic properties, we demonstrate then an alternative method which
makes it possible to evaluate the next term in the asymptotic expansion for
both the strips and layers. It gives, in particular, a criterion for the
bound-state existence in the critical case when the added volume is zero.

</DOC>
<DOC>
<DOCNO> 9907 </DOCNO>
Nonlinear acoustic and microwave absorption in disordered semiconductors


  Nonlinear hopping absorption of ultrasound and electromagnetic waves in
amorphous and doped semiconductors is considered. It is shown that even at low
amplitudes of the electric (or acoustic) field the nonlinear corrections to the
relaxational absorption appear anomalously large. The physical reason for such
behavior is that the nonlinear contribution is dominated by a small group of
close impurity pairs having one electron per pair. Since the group is small, it
is strongly influenced by the field. An external magnetic field strongly
influences the absorption by changing the overlap between the pair components'
wave functions. It is important that the influence is substantially different
for the linear and nonlinear contributions. This property provides an
additional tool to extract nonlinear effects.

</DOC>
<DOC>
<DOCNO> 102357 </DOCNO>
A new property of absorbed diffusions


  We consider stochastic diffusion processes absorbed at the boundary of a
domain. It is shown that there exist initial distributions which ensure a given
decreasing of density of the absorbed process.

</DOC>
<DOC>
<DOCNO> 101912 </DOCNO>
The Geometry of Relativistic Rheonomic Lagrange Spaces


  The paper contains a geometrization of a time dependent Lagrangian function
defined on the 1-jet space J^1(R,M) which identifies with R\times TM. The
reader is invited to compare this geometrization with that developped by Miron
and Anastasiei.

</DOC>
<DOC>
<DOCNO> 101757 </DOCNO>
Covariance systems


  We introduce new definitions of states and of representations of covariance
systems. The GNS-construction is generalized to this context. It associates a
representation with each state of the covariance system. Next, states are
extended to states of an appropriate covariance algebra. Two applications are
given. We describe a nonrelativistic quantum particle, and we give a simple
description of the quantum spacetime model introduced by Doplicher et al.

</DOC>
<DOC>
<DOCNO> 116747 </DOCNO>
Ionospheric effects of the solar flares of September 23, 1998 and July


  This paper presents data from first GPS measurements of global response of
the ionosphere to solar flares of September 23, 1998 and July 29, 1999. The
analysis used novel technology of a global detection of ionospheric effects
from solar flares (GLOBDET) as developed by one of the authors (Afraimovich E.
L.). The essence of the method is that use is made of appropriate filtering and
a coherent processing of variations in total electron content (TEC) in the
ionosphere which is determined from GPS data, simultaneously for the entire set
of visible (over a given time interval) GPS satellites at all stations used in
the analysis. It was found that fluctuations of TEC, obtained by removing the
linear trend of TEC with a time window of about 5 min, are coherent for all
stations and beams to the GPS satellites on the dayside of the Earth. The time
profile of TEC responses is similar to the time behavior of hard X-ray emission
variations during flares in the energy range 25-35 keV if the relaxation time
of electron density disturbances in the ionosphere of order 50-100 s is
introduced. No such effect on the nightside of the Earth has been detected yet.

</DOC>
<DOC>
<DOCNO> 69414 </DOCNO>
Quark Hadron Continuity in QCD with one Flavor


  We study QCD with one flavor at finite baryon density. In the limit of very
high baryon density the system is expected to be a color superconductor. In the
case of one flavor, the order parameter is in a $\bar 3$ of color and has total
angular momentum one. We show that in weak coupling perturbation theory, the
energetically preferred phase exhibits ``color-spin-locking'', i.e. the color
and spin direction of the condensate are aligned. We discuss the properties of
this phase and argue that it shares important features of the hadronic phase at
low density. In particular, we find an unbroken rotational symmetry, spin 3/2
quasiparticles, and an unusual mechanism for quark-anti-quark condensation. Our
results are relevant to three flavor QCD in the regime where the strange quark
mass is bigger than the critical value for color-flavor-locking. We find that
the gaps in this case are on the order of one MeV.

</DOC>
<DOC>
<DOCNO> 174520 </DOCNO>
Azimuthal Dependence of Pion Interferometry at the AGS


  Two-pion correlation functions, measured as a function of azimuthal emission
angle with respect to the reaction plane, provide novel information on the
anisotropic shape and orientation of the pion-emitting zone formed in heavy ion
collisions. We present the first experimental determination of this
information, for semi-central Au+Au collisions at 2-6 AGeV. The source
extension perpendicular to the reaction plane is greater than the extension in
the plane, and tilt of the pion source in coordinate space is found to be
opposite its tilt in momentum space.

</DOC>
<DOC>
<DOCNO> 11543 </DOCNO>
The Creation of Spectral Gaps by Graph Decoration


  We present a mechanism for the creation of gaps in the spectra of
self-adjoint operators defined over a Hilbert space of functions on a graph,
which is based on the process of graph decoration. The resulting Hamiltonians
can be viewed as associated with discrete models exhibiting a repeated local
structure and a certain bottleneck in the hopping amplitudes.

</DOC>
<DOC>
<DOCNO> 13940 </DOCNO>
Stripes and superconducting pairing in the t-J model with Coulomb


  We study the competition between long- and short-range interactions among
charge carriers in strongly-correlated electronic systems employing a new
method which combines the density-matrix renormalization-group technique with a
self-consistent treatment of the long-range interactions.
  We apply the method to an extended t-J model which exhibits ``stripe'' order.
The Coulomb interactions, while not destroying stripes, induce large transverse
stripe fluctuations with associated charge delocalization. This leads to a
substantial Coulomb-repulsion-induced {\it enhancement} of long-range
superconducting pair-field correlations.

</DOC>
<DOC>
<DOCNO> 13418 </DOCNO>
Statistical mechanics of fluidized granular media: short range velocity


  A statistical mechanical study of fluidized granular media is presented.
Using a special energy injection mechanism, homogeneous fluidized stationary
states are obtained. Molecular dynamics simulations and theoretical analysis of
the inelastic hard-disk model show that there is a large asymmetry in the
two-particle distribution function between pairs that approach and separate.
Large velocity correlations appear in the postcollisional states, due to the
dissipative character of the collision rule. These correlations can be well
characterized by a state dependent pair correlation function at contact.
  It is also found that velocity correlations are present for pairs that are
about to collide. Particles arrive to collisions with a higher probability that
their velocities are parallel rather that antiparallel. These dynamical
correlations lead to a decrease of the pressure and of the collision frequency
as compared to their Enskog values. A phenomenological modified equation of
state is presented.

</DOC>
<DOC>
<DOCNO> 85032 </DOCNO>
The Energy Distribution in a Static Spherically Symmetric Nonsingular


  We calculate the energy distribution in a static spherically symmetric
nonsingular black hole space-time by using the Tolman's energy-momentum
complex. All the calculations are performed in quasi-Cartesian coordinates. The
energy distribution is positive everywhere and be equal to zero at origin. We
get the same result as obtained by Y-Ching Yang by using the Einstein's and
Weinberg's prescriptions.

</DOC>
<DOC>
<DOCNO> 178771 </DOCNO>
Isospin dependence of liquid-gas phase transition in hot asymmetric


  By using the Furnstahl, Serot and Tang's model, the effect of density
dependence of the effective nucleon-nucleon-rho-meson (NN-rho) coupling on the
liquid-gas phase transition in hot asymmetric nuclear matter is investigated. A
limit pressure p_lim has been found. We found that the liquid-gas phase
transition cannot take place if p>p_lim. The binodal surface for density
dependent NN-rho coupling situation is addressed.

</DOC>
<DOC>
<DOCNO> 69809 </DOCNO>
1/m_Q Corrections to the Heavy-to-Light-Vector Transitions in the HQET


  Within the HQET, the heavy to light vector meson transitions are
systematically analyzed to the order of 1/m_Q. Besides the four universal
functions at the leading order, there are twenty-two independent universal form
factors at the order of 1/m_Q. Both the semileptonic decay B->\rho which is
relevant to the |V_{ub}| extraction, and the penguin induced decay B -> K^*
which is important to new physics discovering, depend on these form factors.
Phenomenological implications are discussed.

</DOC>
<DOC>
<DOCNO> 69777 </DOCNO>
Topological invariant variables in QCD


  We show that the class of functions of topologically nontrivial gauge
transformations in QCD includes a zero-mode of the Gauss law constraint. The
equivalent unconstrained system compatible with Feynman's integral is derived
in terms of topological invariant variables, where the zero-mode is identified
with the winding number collective variable and leads to the dominance of the
Wu-Yang monopole. Physical consequences of Feynman's path integral in terms of
the topological invariant variables are studied.

</DOC>
<DOC>
<DOCNO> 13774 </DOCNO>
Averaging rheological quantities in descriptions of soft glassy


  Many mean-field models have been introduced to describe the mechanical
behavior of glassy materials. They often rely on averages performed over
distributions of elements or states. We here underline that averaging is a more
intricate procedure in mechanics than in more classical situations such as
phase transitions in magnetic systems. This leads us to modify the predictions
of the recently proposed SGR model for soft glassy materials, for which we
suggest that the viscosity should diverge at the glass transition temperature
$T_g$ with an exponential form $\eta \sim \exp(\frac{A}{T-T_g})$.

</DOC>
<DOC>
<DOCNO> 9931 </DOCNO>
Aharonov-Bohm spectral features and coherence lengths in carbon


  The electronic properties of carbon nanotubes are investigated in the
presence of disorder and a magnetic field parallel or perpendicular to the
nanotube axis. In the parallel field geometry, the $\phi_{0}(=hc/e)$-periodic
metal-insulator transition (MIT) induced in metallic or semiconducting
nanotubes is shown to be related to a chirality-dependent shifting of the
energy of the van Hove singularities (VHSs). The effect of disorder on this
magnetic field-related mechanism is considered with a discussion of mean free
paths, localization lengths and magnetic dephasing rate in the context of
recent experiments.

</DOC>
<DOC>
<DOCNO> 100355 </DOCNO>
Multilinear weighted convolution of $L^2$ functions, and applications to


  The $X^{s,b}$ spaces, as used by Beals, Bourgain, Kenig-Ponce-Vega,
Klainerman-Machedon and others, are fundamental tools to study the
low-regularity behaviour of non-linear dispersive equations. It is of
particular interest to obtain bilinear or multilinear estimates involving these
spaces. By Plancherel's theorem and duality, these estimates reduce to
estimating a weighted convolution integral in terms of the $L^2$ norms of the
component functions. In this paper we systematically study weighted convolution
estimates on $L^2$. As a consequence we obtain sharp bilinear estimates for the
KdV, wave, and Schr\"odinger $X^{s,b}$ spaces.

</DOC>
<DOC>
<DOCNO> 83143 </DOCNO>
Planning with Incomplete Information


  Planning is a natural domain of application for frameworks of reasoning about
actions and change. In this paper we study how one such framework, the Language
E, can form the basis for planning under (possibly) incomplete information. We
define two types of plans: weak and safe plans, and propose a planner, called
the E-Planner, which is often able to extend an initial weak plan into a safe
plan even though the (explicit) information available is incomplete, e.g. for
cases where the initial state is not completely known. The E-Planner is based
upon a reformulation of the Language E in argumentation terms and a natural
proof theory resulting from the reformulation. It uses an extension of this
proof theory by means of abduction for the generation of plans and adopts
argumentation-based techniques for extending weak plans into safe plans. We
provide representative examples illustrating the behaviour of the E-Planner, in
particular for cases where the status of fluents is incompletely known.

</DOC>
<DOC>
<DOCNO> 10388 </DOCNO>
Local entropic effects of polymers grafted to soft interfaces


  In this paper, we study the equilibrium properties of polymer chains
end-tethered to a fluid membrane. The loss of conformational entropy of the
polymer results in an inhomogeneous pressure field that we calculate for
gaussian chains. We estimate the effects of excluded volume through a relation
between pressure and concentration. Under the polymer pressure, a soft surface
will deform. We calculate the deformation profile for a fluid membrane and show
that close to the grafting point, this profile assumes a cone-like shape,
independently of the boundary conditions. Interactions between different
polymers are also mediated by the membrane deformation. This pair-additive
potential is attractive for chains grafted on the same side of the membrane and
repulsive otherwise.

</DOC>
<DOC>
<DOCNO> 69087 </DOCNO>
Detecting the MSSM Higgs Bosons at Future $e^+e^-$ Colliders


  We investigate the possibility of detecting the Higgs bosons predicted in the
Minimal Supersymmetric extension of the Standard Model $(h^0, H^0, A^0,
H^\pm)$, with the reactions $e^{+}e^{-}\to b\bar b h^0 (H^0, A^0)$, and
$e^+e^-\to \tau^-\bar \nu_\tau H^+, \tau^+\nu_\tau H^-$, using the helicity
formalism. We analyze the region of parameter space $(m_{A^0}-\tan\beta)$ where
$h^0, H^0, A^0$ and $H^\pm$ could be detected in the limit when $\tan\beta$ is
large. The numerical computation is done considering two stages of a possible
Next Linear $e^{+}e^{-}$ Collider: the first with $\sqrt{s}=500$ $GeV$ and
design luminosity 50 $fb^{-1}$, and the second with $\sqrt{s}=1$ $TeV$ and
luminosity 100-200 $fb^{-1}$.

</DOC>
<DOC>
<DOCNO> 99387 </DOCNO>
Semiclassical limit for the Schroedinger equation with a short scale


  We consider the dynamics generated by the Schroedinger operator
$H=-{1/2}\Delta + V(x) + W(\epsi x)$, where $V$ is a lattice periodic potential
and $W$ an external potential which varies slowly on the scale set by the
lattice spacing. We prove that in the limit $\epsi \to 0$ the time dependent
position operator and, more generally, semiclassical observables converge
strongly to a limit which is determined by the semiclassical dynamics.

</DOC>
<DOC>
<DOCNO> 170796 </DOCNO>
Entanglement Optimization for Pairs of Qubits


  Local Operations enhancing the entanglement of bipartite quantum states are
of great interest in quantum information processing. Subject of this paper are
local selective operations acting on single copies of states. Such operations
can lead to larger entanglement with respect to a certain measure as studies
before by the Horodeckis and A. Kent et al. (PRA 60,PRL 81 and 83). We present
a complete characterisation of all local operations yielding optimal
entanglement for pairs of qubits, extending former results of A. Kent et al. We
introduce a new technique for the classification of states according to their
behaviour under entanglement optimizing operations, using the entanglement
properties of the support of density matrices.

</DOC>
<DOC>
<DOCNO> 84126 </DOCNO>
Coordinate Singularities in Harmonically-sliced Cosmologies


  Harmonic slicing has in recent years become a standard way of prescribing the
lapse function in numerical simulations of general relativity. However, as was
first noticed by Alcubierre (1997), numerical solutions generated using this
slicing condition can show pathological behaviour. In this paper, analytic and
numerical methods are used to examine harmonic slicings of Kasner and Gowdy
cosmological spacetimes. It is shown that in general the slicings are prevented
from covering the whole of the spacetimes by the appearance of coordinate
singularities. As well as limiting the maximum running times of numerical
simulations, the coordinate singularities can lead to features being produced
in numerically evolved solutions which must be distinguished from genuine
physical effects.

</DOC>
<DOC>
<DOCNO> 70519 </DOCNO>
The dipole picture of small x physics (a summary of the Amirim meeting)


  A personal summary of the discussions which took place at the informal
meeting in Amirim, Israel from June 1-4 2000, concerning the dipole picture of
small-$x$ physics is presented. The broad aim of the meeting was to address the
question ``Has HERA reached a new QCD regime (at small $x$) ?''. The new regime
in question is the high-density, but weak-coupling, limit of perturbative QCD.

</DOC>
<DOC>
<DOCNO> 117049 </DOCNO>
Psychophysical quantum-string Weltdrama


  Hypothesis of an existence of the universal quantum string field for all
interactive phenomena is formulated. Its practical value is clarified.

</DOC>
<DOC>
<DOCNO> 100665 </DOCNO>
Hodge-Gaussian maps


  Let $X$ be a compact K\"{a}hler manifold, and let $L$ be a line bundle on
$X.$ Define $I_k(L)$ to be the kernel of the multiplication map $ Sym^k H^0 (L)
\to H^0 (L^k).$ For all $h \leq k,$ we define a map $\rho : I_k(L) \to Hom
(H^{p,q} (L^{-h}), H^{p+1,q-1} (L^{k-h})).$ When $L = K_X$ is the canonical
bundle, the map $\rho$ computes a second fundamental form associated to the
deformations of $X.$ If $X=C$ is a curve, then $\rho$ is a lifting of the Wahl
map $I_2(L) \to H^0 (L^2 \otimes K_C^2).$ We also show how to generalize the
construction of $\rho$ to the cases of harmonic bundles and of couples of
vector bundles.

</DOC>
<DOC>
<DOCNO> 151446 </DOCNO>
Nondegenerate Super-Anti-de Sitter Algebra and a Superstring Action


  We construct an Anti-de Sitter(AdS) algebra in a nondegenerate superspace.
Based on this algebra we construct a covariant kappa-symmetric superstring
action, and we examine its dynamics: Although this action reduces to the usual
Green-Schwarz superstring action in flat limit, the auxiliary fermionic
coordinates of the nondegenerate superspace becomes dynamical in the AdS
background.

</DOC>
<DOC>
<DOCNO> 99699 </DOCNO>
The Characteristic Length Scale of the Intermediate Structure in


  In a turbulent boundary layer over a smooth flat plate with zero pressure
gradient, the intermediate structure between the viscous sublayer and the free
stream consists of two layers: one adjacent to the viscous sublayer and one
adjacent to the free stream. When the level of turbulence in the free stream is
low, the boundary between the two layers is sharp and both have a self-similar
structure described by Reynolds-number-dependent scaling (power) laws. This
structure introduces two length scales: one --- the wall region thickness ---
determined by the sharp boundary between the two intermediate layers, the
second determined by the condition that the velocity distribution in the first
intermediate layer be the one common to all wall-bounded flows, and in
particular coincide with the scaling law previously determined for pipe flows.
Using recent experimental data we determine both these length scales and show
that they are close. Our results disagree with the classical model of the "wake
region".

</DOC>
<DOC>
<DOCNO> 84417 </DOCNO>
Inertial Effects on Berry's Phase of Neutrino Oscillations


  The Berry phase of mixed states, as neutrino oscillations, is calculated in a
accelerating and rotating reference frame. It turns out to be depending on the
vacuum mixing angle, the mass--squared difference and on the coupling between
the momentum of the neutrino and the spinorial connection. Berry's phase for
solar neutrinos and its geometrical aspects are also discussed.

</DOC>
<DOC>
<DOCNO> 7809 </DOCNO>
Molecular Dynamics for Fermions


  The time-dependent variational principle for many-body trial states is used
to discuss the relation between the approaches of different molecular dynamics
models to describe indistinguishable fermions. Early attempts to include
effects of the Pauli principle by means of nonlocal potentials as well as more
recent models which work with antisymmetrized many-body states are reviewed
under these premises.
  Keywords: Many-body theory; Fermion system; Molecular dynamics; Wave-packet
dynamics; Time-dependent variational principle; Statistical properties;
Canonical ensemble; Ergodicity; Time averaging

</DOC>
<DOC>
<DOCNO> 81005 </DOCNO>
Do we understand the unquenched value of fB?


  I review our qualitative understanding of the increase in the value of the B
meson decay constant (fB), when dynamical fermions are included in lattice QCD
calculations.

</DOC>
<DOC>
<DOCNO> 39899 </DOCNO>
Linac*LHC based ep, gamma-p, eA, gamma-A and FEL gamma-A Colliders


  Main parameters of different colliders which can be realized if a special 1
TeV energy linear electron accelerator or corresponding linear collider is
constructed tangential to LHC are estimated. It is shown that
L_ep=10^32cm^-2s^-1 at sqrt(s_ep)=5.29 TeV can be achieved within moderate
upgrade of LHC parameters. Then, gamma-p collider with the same luminosity and
sqrt(s)=4.82 TeV can be realized using Compton backscattering of laser beam off
the electron beam. Concerning the nucleus beam, L*A=10^31cm^-2s^-1 can be
achieved at least for light and medium nuclei both for eA and gamma-A options.
Finally, colliding of the FEL beam from an electron linac with nucleus beams
from LHC will give a new opportunity to investigate nuclear spectroscopy and
photo-nuclei reactions.

</DOC>
<DOC>
<DOCNO> 150960 </DOCNO>
Vacuum energy of a massive scalar field in the presence of a


  We compute the ground state energy of a massive scalar field in the
background of a cylindrical shell whose potential is given by a delta function.
The zero point energy is expressed in terms of the Jost function of the related
scattering problem, the renormalization is performed with the help of the heat
kernel expansion. The energy is found to be negative for attractive and for
repulsive backgrounds as well.

</DOC>
<DOC>
<DOCNO> 9098 </DOCNO>
Phase Transitions in Non-Equilibrium Systems


  Phase transitions and critical behavior of driven systems are reviewed.
Models exhibiting phase transitions, spontaneous symmetry breaking, phase
separation and coarsening processes in d=1 dimension are discussed.

</DOC>
<DOC>
<DOCNO> 85317 </DOCNO>
Twisted Kac-Moody Algebras And The Entropy Of AdS$_3$ Black Hole


  We show that an $SL(2,R)_L \times SL(2,R)_R$ Chern-Simons theory coupled to a
source on a manifold with the topology of a disk correctly describes the
entropy of the AdS$_3$ black hole. The resulting boundary WZNW theory leads to
two copies of a twisted Kac-Moody algebra, for which the respective Virasoro
algebras have the same central charge $c$ as the corresponding untwisted
theory. But the eigenvalues of the respective $L_0$ operators are shifted. We
show that the asymptotic density of states for this theory is, up to
logarithmic corrections, the same as that obtained by Strominger using the
asymptotic symmetry of Brown and Henneaux.

</DOC>
<DOC>
<DOCNO> 70506 </DOCNO>
A dynamic mass definition near the t t-bar threshold


  Starting from general considerations about the different concepts which exist
for the definition of the quark mass near the pair production threshold, we
introduce the definition of a mass with a dynamic degree of freedom that
extends the previously given concept of the static PS mass.

</DOC>
<DOC>
<DOCNO> 99467 </DOCNO>
Claspers and finite type invariants of links


  We introduce the concept of `claspers,' which are surfaces in 3-manifolds
with some additional structure on which surgery operations can be performed.
Using claspers we define for each positive integer k an equivalence relation
on links called `C_k-equivalence,' which is generated by surgery operations of
a certain kind called `C_k-moves'. We prove that two knots in the 3-sphere are
C_{k+1}-equivalent if and only if they have equal values of
Vassiliev-Goussarov invariants of type k with values in any abelian groups.
This result gives a characterization in terms of surgery operations of the
informations that can be carried by Vassiliev-Goussarov invariants. In the
last section we also describe outlines of some applications of claspers to
other fields in 3-dimensional topology.

</DOC>
<DOC>
<DOCNO> 118770 </DOCNO>
Young Star Clusters: Metallicities, Ages, and Masses


  Observations of Young Star Cluster ({\bf YSC}) systems in interacting
galaxies are reviewed with particular emphasis on their Luminosity Functions
({\bf LF}) and colour distributions. A few spectroscopic abundance measurements
are available. They will be compared to YSC abundance predictions from spiral
galaxy models. Evolutionary synthesis models allow to derive ages for
individual YSCs on the basis of their broad band colours. With individual YSC
ages, models predict the future colour and luminosity evolution of the YSC
systems that will be compared - after a Hubble time - to observations of old
Globular Cluster ({\bf GC}) systems. Using model M/L ratios as a function of
age, YSC masses can be estimated. Age spread effects in young systems can cause
the shape of the LF to substantially differ from the shape of the underlying
mass function. Major sources of uncertainty are the metallicity, dust
reddening, and observational colour uncertainties.

</DOC>
<DOC>
<DOCNO> 69866 </DOCNO>
Excited heavy baryon masses in HQET QCD sum rules


  We construct the interpolating currents for the fourteen p-wave excited heavy
baryons in the framework of heavy quark effective theory (HQET). At the leading
order in the 1/m_Q expansion these interpolating currents do not mix different
states with the same J^P with each other. We use QCD sum rule to calculate the
masses of the p-wave excited J=1/2 spin doublet heavy baryons in the
m_Q~infinity limit. We discuss some implications of our results.

</DOC>
<DOC>
<DOCNO> 120506 </DOCNO>
A combined HST/CFH12k/XMM survey of X-ray luminous clusters of galaxies


  We describe a project to study a sample of X-ray luminous clusters of
galaxies at redshift z~0.2 at several scales (with HST/WFPC2 and CFHT/CFH12k)
and wavebands (optical and X-ray). The main aims of the project are (i) to
determine the mass profiles of the clusters on scales ranging from ~10 kpc/h to
>1.5 Mpc/h using weak and strong lensing, thereby testing theoretical
predictions of a ``universal mass profile'', and (ii) to calibrate the M_tot -
T_X relation in view of future application in the study of the evolution of the
cluster mass function at higher redshift.

</DOC>
<DOC>
<DOCNO> 10611 </DOCNO>
Canted ground state in artificial molecules at high magnetic fields


  We analyze the transitions that a magnetic field provokes in the ground state
of an artificial homonuclear diatomic molecule. For that purpose, we have
performed numerical diagonalizations for a double quantum dot around the regime
of filling factor 2. We present phase diagrams in terms of tunneling and Zeeman
couplings, and confinement strength. We identify a series of transitions from
ferromagnetic to symmetric states through a set of canted states with
antiferromagnetic couping between the two quantum dots.

</DOC>
<DOC>
<DOCNO> 70591 </DOCNO>
Monopoles and Dyons in SU(5) Gauge Unification (with relation to a Dual


  This article presents a fairly complete description of the monopoles and
dyons arising from an SU(5) gauge unification of the standard model. Topics
discussed include: the spectrum of SU(5) monopoles; their gauge equivalence
structure; their spherical symmetry; the construction of dyons; global charge;
the intrinsic angular momenta of scalar boson-monopole composites and monopole
gauge excitations; and the effects of a theta vacuum. The relevance of each of
these topics to constructing a dual description of the standard model with
SU(5) solitons is discussed in detail.

</DOC>
<DOC>
<DOCNO> 9457 </DOCNO>
Weak antiferromagnetism due to Dzyaloshinskii-Moriya interaction in


  The antiferromagnetic insulating cuprate Ba$_3$Cu$_2$O$_4$Cl$_2$ contains
folded CuO$_2$ chains with four magnetic copper ions ($S=1/2$) per unit cell.
An underlying multiorbital Hubbard model is formulated and the superexchange
theory is developed to derive an effective spin Hamiltonian for this cuprate.
The resulting spin Hamiltonian involves a Dzyaloshinskii-Moriya term and a more
weak symmetric anisotropic exchange term besides the isotropic exchange
interaction. The corresponding Dzyaloshinskii-Moriya vectors of each magnetic
Cu-Cu bond in the chain reveal a well defined spatial order. Both, the
superexchange theory and the complementary group theoretical consideration,
lead to the same conclusion on the character of this order. The analysis of the
ground-state magnetic properties of the derived model leads to the prediction
of an additional noncollinear modulation of the antiferromagnetic structure.
This weak antiferromagnetism is restricted to one of the Cu sublattices.

</DOC>
<DOC>
<DOCNO> 151114 </DOCNO>
A Class of Anomaly-Free Gauge Theories


  We report on a detailed calculation of the anomaly coefficients for the odd
and even parts of the $Z_2$-graded representation $\theta$ of the Lie algebra
Lie$ G$ on the exterior algebra of dimension $2^n$ assuming that $G\subset
U(n)$. The coefficients vanish provided $G\subset SU(n)$ and $n\ne3$. The
singular role of the gauge group SU(3) is emphasized.
  The Standard Model is covered by this result.

</DOC>
<DOC>
<DOCNO> 7930 </DOCNO>
Counter-ion release and electrostatic adsorption


  The effective charge of a rigid polyelectrolyte (PE) approaching an
oppositely charged surface is studied. The cases of a weak (annealed) and
strongly charged PE with condensed counterions (such as DNA) are discussed. In
the most interesting case of the adsorption onto a substrate of low dielectric
constant (such as a lipid membrane or a mica sheet) the condensed counterions
are not always released as the PE approaches the substrate, because of the
major importance of the image charge effect. For the adsorption onto a surface
with freely moving charges, the image charge effect becomes less important and
full release is often expected.

</DOC>
<DOC>
<DOCNO> 116546 </DOCNO>
Shape of the amplification line corresponding to an adjacent transition


  An analysis is made of the effect of a strong field on the shape of the
amplification spectral line for mono-velocity V-type three-level atoms. There
are three strong-field contributions, differing in their dependence on the set
of relaxation parameters of the medium and on the differences among the
populations corresponding to the Raman transitions. An analysis is made of the
conditions under which each of the contributions is predominant. The change in
the line shape by an intensified external field is found for each case. Neon
atoms are discussed as an example. The results are compared with those
corresponding to a Maxwellian velocity distribution.

</DOC>
<DOC>
<DOCNO> 11939 </DOCNO>
Fermi Surface, Surface States, and Surface Reconstruction in Sr2RuO4


  The electronic structure of Sr2RuO4 is investigated by high angular
resolution ARPES at several incident photon energies. We address the
controversial issues of the Fermi surface (FS) topology and of the van Hove
singularity at the M point, showing that a surface state and the replica of the
primary FS due to (sqrt2 x sqrt2) surface reconstruction are responsible for
previous conflicting interpretations. The FS thus determined by ARPES is
consistent with the de Haas-van Alphen results, and it provides additional
information on the detailed shape of the alpha, beta and gamma sheets.

</DOC>
<DOC>
<DOCNO> 71656 </DOCNO>
On the color simple group from chiral electroweak gauge groups


  Following the pioneering Okubo scrutiny of gauge simple groups for the
quantum chromodynamics we show the constraints coming from the wondrous
predictive leptoquark-bilepton flavordynamics connecting the number of color
charges to solution of the flavor question and to an electric charge
quantization unconstrained from the Dirac, Majorana or Dirac--Majorana
character of massive neutrino.

</DOC>
<DOC>
<DOCNO> 117169 </DOCNO>
Parity and time reversal violating nuclear polarizability


  We propose a nuclear mechanism which can induce an atomic electric dipole
moment (EDM). Parity and time reversal violating (P,T-odd) nuclear forces
generate a mixed P,T-odd nuclear polarizability beta_{ik} (defined by an energy
shift U = -beta_{ik} E_{i}H_{k}, E is electric field and H magnetic field). The
interaction of atomic electrons with beta_{ik} produces an atomic EDM. We
performed an analytical calculation of the P,T-odd nuclear polarizability and
estimated the value for the induced atomic EDM. The measurements of atomic EDMs
can provide information about P,T-odd nuclear forces and test models of
CP-violation.

</DOC>
<DOC>
<DOCNO> 119183 </DOCNO>
Galactic 1.275 MeV emission from ONe novae and its detectability by


  Models of Galactic 1.275 MeV emission produced by the decay of the
radionuclide $^{22}$Na have been computed. Several frequency-spatial
distributions of novae have been investigated using recent results of nova
rates and spatial distributions of novae in our Galaxy. These models allow us
to estimate the lower-limit of the $^{22}$Na mass ejected per ONe nova
detectable with the future spectrometer (SPI) of the INTEGRAL observatory as a
function of the frequency-spatial distribution of ONe novae in the Galaxy.
Calculations using recent estimations of the expected $^{22}$Na mass ejected
per ONe nova show that the detection of the Galactic emission of 1.275 MeV
photons will be difficult with the future spectrometer of the INTEGRAL
observatory, whereas the cumulative emission around the Galactic center has
some chances to be detected during the deep survey of the central radian of the
Galaxy.

</DOC>
<DOC>
<DOCNO> 10903 </DOCNO>
Superconductivity from Undressing. II. Single Particle Green's Function


  Experimental evidence indicates that the superconducting transition in high
$T_c$ cuprates is an 'undressing' transition. Microscopic mechanisms giving
rise to this physics were discussed in the first paper of this series. Here we
discuss the calculation of the single particle Green's function and spectral
function for Hamiltonians describing undressing transitions in the normal and
superconducting states. A single parameter, $\Upsilon$, describes the strength
of the undressing process and drives the transition to superconductivity. In
the normal state, the spectral function evolves from predominantly incoherent
to partly coherent as the hole concentration increases. In the superconducting
state, the 'normal' Green's function acquires a contribution from the anomalous
Green's function when $ \Upsilon$ is non-zero; the resulting contribution to
the spectral function is $positive$ for hole extraction and $negative$ for hole
injection. It is proposed that these results explain the observation of sharp
quasiparticle states in the superconducting state of cuprates along the
$(\pi,0)$ direction and their absence along the $(\pi,\pi)$ direction.

</DOC>
<DOC>
<DOCNO> 68719 </DOCNO>
Beam Polarization and Spin Correlation Effects in Chargino Production


  We study chargino production e^+ e^- -> chi^+_1 chi^-_1 and the subsequent
leptonic decay chi^-_1\to chi^0_1 e^- nu_e including the complete spin
correlations between production and decay. We work out the advantages of
polarizing the e^+ and e^- beams. We study in detail the polarized cross
sections, the angular distribution and the forward--backward asymmetry of the
decay electron. They can be used to determine the sneutrino mass
m_{\tilde{\nu}_e}.

</DOC>
<DOC>
<DOCNO> 102917 </DOCNO>
Method of Replacing the Variables for Generalized Symmetry of D'Alembert


  By symmetry of the partial differential equation L'\phi'(x')=0 with respect
to the variables replacement x'=x'(x), \phi'=\phi'(\Phi\phi) it is advanced to
understand the compatibility of engaging equations system A\phi'(\Phi\phi)=0,
L\phi(x)=0, where A\phi'(\Phi\phi)=0 is obtained from the initial equation by
replacing the variables, L'=L, \Phi(x) is some weight function. If the equation
A\phi'(\Phi\phi)=0 may be transformed to the form L(\Psi\phi)=0, where \Psi(x)
is the weight function, the symmetry will be named the standard Lie symmetry,
otherwise the generalized symmetry.
     It is shown that with the given understanding of the symmetry, D'Alembert
equation for one component field is invariant with respect to any arbitrary
reversible coordinate transformations x'=x'(x). In particular, they contain the
transformations of the conformal and Galilei groups realizing the type of
standard and generalized symmetry for \Phi(x)=\phi'(x'\to x)/\phi(x).

</DOC>
<DOC>
<DOCNO> 85299 </DOCNO>
Differential Rotation in Neutron Stars: Magnetic Braking and Viscous


  Diffferentially rotating stars can support significantly more mass in
equilibrium than nonrotating or uniformly rotating stars, according to general
relativity. The remnant of a binary neutron star merger may give rise to such a
``hypermassive'' object. While such a star may be dynamically stable against
gravitational collapse and bar formation, the radial stabilization due to
differential rotation is likely to be temporary. Magnetic braking and viscosity
combine to drive the star to uniform rotation, even if the seed magnetic field
and the viscosity are small. This process inevitably leads to delayed collapse,
which will be accompanied by a delayed gravitational wave burst and, possibly,
a gamma-ray burst. We provide a simple, Newtonian, MHD calculation of the
braking of differential rotation by magnetic fields and viscosity. The star is
idealized as a differentially rotating, infinite cylinder consisting of a
homogeneous, incompressible conducting gas. We solve analytically the simplest
case in which the gas has no viscosity and the star resides in an exterior
vacuum. We treat numerically cases in which the gas has internal viscosity and
the star is embedded in an exterior, low-density, conducting medium. Our
evolution calculations are presented to stimulate more realistic MHD
simulations in full 3+1 general relativity. They serve to identify some of the
key physical and numerical parameters, scaling behavior and competing
timescales that characterize this important process.

</DOC>
<DOC>
<DOCNO> 100412 </DOCNO>
Multiplets of representations and Kostant's Dirac operator for equal


  Let g be a semi-simple Lie algebra and let h be a reductive subalgebra of
maximal rank in g. Given any irreducible representation of g, consider its
tensor product with the spin representation associated to the orthogonal
complement of h in g. Gross, Kostant, Ramond, and Sternberg recently proved a
generalization of the Weyl character formula which decomposes the signed
character of this product representation in terms of the characters of a set of
irreducible representations of h, called a multiplet. Kostant then constructed
a formal h-equivariant Dirac operator on such product representations whose
kernel is precisely the multiplet of h-representations corresponding to the
given representation of g.
  We reproduce these results in the Kac-Moody setting for the extended loop
algebras Lg and Lh. We prove a homogeneous generalization of the Weyl-Kac
character formula, which now yields a multiplet of irreducible positive energy
representations of Lh associated to any irreducible positive energy
representation of Lg. We construct a Lh-equivariant operator, analogous to
Kostant's Dirac operator, on the tensor product of a representation of Lg with
the spin representation associated to the complement of Lh in Lg. We then prove
that the kernel of this operator gives the Lh-multiplet corresponding to the
original representation of Lg.

</DOC>
<DOC>
<DOCNO> 13436 </DOCNO>
Magnetoplasmon excitations in an array of periodically modulated quantum


  Motivated by the recent experiment of Hochgraefe et al., we have investigated
the magnetoplasmon excitations in a periodic array of quantum wires with a
periodic modulation along the wire direction. The equilibrium and dynamic
properties of the system are treated self-consistently within the
Thomas-Fermi-Dirac-von Weizsaecker approximation. A calculation of the
dynamical response of the system to a far-infrared radiation field reveals a
resonant anticrossing between the Kohn mode and a finite-wavevector
longitudinal excitation which is induced by the density modulation along the
wires. Our theoretical calculations are found to be in excellent agreement with
experiment.

</DOC>
<DOC>
<DOCNO> 116356 </DOCNO>
A Numerical Simulation of the Reconnection Layer in 2D Resistive MHD


  In this paper we present a two-dimensional, time dependent, numerical
simulation of a reconnection current layer in incompressible resistive
magnetohydrodynamics with uniform resistivity in the limit of very large
Lundquist numbers. We use realistic boundary conditions derived consistently
from the outside magnetic field, and we also take into account the effect of
the back pressure from flow into the the separatrix region. We find that within
a few Alfven times the system evolves from an arbitrary initial state to a
steady state consistent with the Sweet--Parker model, even if the initial state
is Petschek-like.

</DOC>
<DOC>
<DOCNO> 8180 </DOCNO>
Universal Ratios in the 2-D Tricritical Ising Model


  We consider the universality class of the two-dimensional Tricritical Ising
Model. The scaling form of the free-energy naturally leads to the definition of
universal ratios of critical amplitudes which may have experimental relevance.
We compute these universal ratios by a combined use of results coming from
Perturbed Conformal Field Theory, Integrable Quantum Field Theory and numerical
methods.

</DOC>
<DOC>
<DOCNO> 70902 </DOCNO>
Dual QCD, Effective String Theory, And Regge Trajectories


  We start with an effective field theory containing classical vortex solutions
and show that the fluctuations of these vortices are described by an effective
string theory. Viewed as a model for long distance QCD, this theory provides a
concrete picture of the QCD string as a fluctuating Abrikosov-Nielsen-Olesen
vortex of a dual superconductor on the border between type I and type II. We
present arguments which suggest that the action of the effective string theory
is the Nambu-Goto action, i.e. the rigidity vanishes. We then use this theory
to calculate the corrections to classical Regge trajectories due to string
fluctuations.

</DOC>
<DOC>
<DOCNO> 151895 </DOCNO>
Scheme-dependence of holographic conformal anomaly in d5 gauged


  Bosonic sector of d5 gauged supergravity with specific parametrization of
full scalar coset is considered (multi-dilaton gravity). Using holographic RG
in the form suggested by de Boer-Verlinde-Verlinde the holographic d4 conformal
anomaly (in the sector of curvature invariants) is found when bulk potential is
not constant. Its comparison with the earlier calculation done in the scheme
where expansion of metric and dilaton over radial coordinate of AdS space is
used demonstrates scheme dependence of holographic conformal anomaly. In
AdS/CFT correspondence where dilatons play role of coupling constants it
coincides with multi-loop conformal anomaly which depends on regularization
scheme in interacting dual QFT. Hence, scheme dependence of holographic
conformal anomaly is consistent with dual QFT expectations.

</DOC>
<DOC>
<DOCNO> 68424 </DOCNO>
Neutrino Proper Time?


  An electron neutrino can have the quantum phase of an electron, i.e. share
its internal clock, if the neutrino takes a path in space-time that is not in
the direction of its energy-momentum. Each flavor neutrino would then have a
different internal clock; a muon neutrino would have a muon clock and a tau
neutrino would have a tau clock. Perhaps surprisingly, there is some evidence
suggesting neutrinos have such clocks. If muon neutrinos travel on space-like
paths then some atmospheric muon neutrinos would take such paths backwards into
outer space and not be observed. These are lost at the source and have nothing
to do with oscillations or flavor-changing in flight. The expected depletion of
source muon neutrinos is shown here to be 9%, which accounts for half of the
missing muon neutrino source flux reported by Super-Kamiokande. Since there is
no depletion in the electron neutrino flux source reported at SK and SN1987A
electron neutrinos seem to have traveled at the speed of light, the electron
neutrino travels on a light-like path. Accelerator-based experiments could be
arranged to confirm the reverse motion of muon neutrinos.

</DOC>
<DOC>
<DOCNO> 67769 </DOCNO>
The KARMEN anomaly, light neutralinos and type II supernovae


  The KARMEN experiment observes a time anomaly in events induced by pion decay
at rest. This anomaly can be ascribed to the production of a new weakly
interacting particle X with mass m_X\sim 34 MeV. We show that a recently
proposed identification of the X particle with the lightest neutralino \chi in
the frame work of the MSSM with broken R parity is in contradiction to optical
observations of type II supernovae.

</DOC>
<DOC>
<DOCNO> 84741 </DOCNO>
Holography and Riemann Surfaces


  We study holography for asymptotically AdS spaces with an arbitrary genus
compact Riemann surface as the conformal boundary. Such spaces can be
constructed from the Euclidean AdS_3 by discrete identifications; the discrete
groups one uses are the so-called classical Schottky groups. As we show, the
spaces so constructed have an appealing interpretation of ``analytic
continuations'' of the known Lorentzian signature black hole solutions; it is
one of the motivations for our generalization of the holography to this case.
We use the semi-classical approximation to the gravity path integral, and
calculate the gravitational action for each space, which is given by the
(appropriately regularized) volume of the space. As we show, the regularized
volume reproduces exactly the action of Liouville theory, as defined on
arbitrary Riemann surfaces by Takhtajan and Zograf. Using the results as to the
properties of this action, we discuss thermodynamics of the spaces and analyze
the boundary CFT partition function. Some aspects of our construction, such as
the thermodynamical interpretation of the Teichmuller (Schottky) spaces, may be
of interest for mathematicians working on Teichmuller theory.

</DOC>
<DOC>
<DOCNO> 67679 </DOCNO>
Alternative Supersymmetric Spectra


  We describe the features of supersymmetric spectra, alternative to and
qualitatively different from that of most versions of the MSSM. The spectra are
motivated by extensions of the MSSM with an extra U(1)' gauge symmetry,
expected in many grand unified and superstring models, which provide a
plausible solution to the mu problem, both for models with supergravity and for
gauge-mediated supersymmetry breaking. Typically, many or all of the squarks
are rather heavy (larger than one TeV), especially for the first two families,
as are the sleptons in the supergravity models. However, there is a richer
spectrum of Higgs particles, neutralinos, and (possibly) charginos. Concrete
examples of such spectra are presented, and the phenomenological implications
are briefly discussed.

</DOC>
<DOC>
<DOCNO> 118317 </DOCNO>
The Elusive Active Nucleus of NGC 4945


  We present new HST NICMOS observations of NGC 4945, a starburst galaxy
hosting a highly obscured active nucleus that is one of the brightest
extragalactic sources at 100 keV. The HST data are complemented with ground
based [FeII] line and mid--IR observations. A 100pc-scale starburst ring is
detected in Pa alpha, while H_2 traces the walls of a super bubble opened by
supernova-driven winds. The conically shaped cavity is particularly prominent
in Pa alpha equivalent width and in the Pa alpha/H_2 ratio. Continuum images
are heavily affected by dust extinction and the nucleus of the galaxy is
located in a highly reddened region with an elongated, disk-like morphology. No
manifestation of the active nucleus is found, neither a strong point source nor
dilution in CO stellar features, which are expected tracers of AGN activity.
Even if no AGN traces are detected in the near-IR, with the currently available
data it is still not possible to establish whether the bolometric luminosity of
the object is powered by the AGN or by the starburst: we demonstrate that the
two scenarios constitute equally viable alternatives. However, the absence of
any signature other than in the hard X-rays implies that, in both scenarios,
the AGN is non-standard: if it dominates, it must be obscured in all
directions, conversely, if the starburst dominates, the AGN must lack UV
photons with respect to X-rays. An important conclusion is that powerful AGNs
can be hidden even at mid-infrared wavelengths and, therefore, the nature of
luminous dusty galaxies cannot be always characterized by long-wavelength data
alone but must be complemented with sensitive hard X-ray observations.

</DOC>
<DOC>
<DOCNO> 71983 </DOCNO>
The d* dibaryon in the extended quark-delocalization, color-screening


  The quark-delocalization, color-screening model, extended by inclusion of a
one-pion-exchange (OPE) tail, is applied to the study of the deuteron and the
d* dibaryon. The results show that the properties of the deuteron (an extended
object) are well reproduced, greatly improving the agreement with experimental
data as compared to our previous study (without OPE). At the same time, the
mass and decay width of the d* (a compact object) are, as expected, not altered
significantly.

</DOC>
<DOC>
<DOCNO> 70667 </DOCNO>
What the Infrared Behavior of QCD Green Functions can tell us about


  We review aspects of confinement in the covariant and local description of
QCD and discuss to what extend our present knowledge of the infrared behavior
of QCD Green functions can support this description. In particular, we
emphasize: the positivity violations of transverse gluon and quark states, the
Kugo-Ojima confinement criterion, and the conditions necessary to avoid the
decomposition property for colored clusters. We summarize how these issues
relate to the infrared behavior of the propagators in Landau gauge QCD as
extracted from solutions to truncated Dyson-Schwinger equations and lattice
simulations.

</DOC>
<DOC>
<DOCNO> 68241 </DOCNO>
Complete Renormalization Group Improvement-Avoiding Factorization and


  For moments of leptoproduction structure functions we show that all
dependence on the renormalization and factorization scales disappears, provided
that all the ultraviolet logarithms involving the physical energy scale Q are
completely resummed. The approach is closely related to Grunberg's method of
Effective Charges. A direct and simple method for extracting the universal
dimensional transmutation parameter of QCD from experimental data is advocated.

</DOC>
<DOC>
<DOCNO> 170544 </DOCNO>
Temporary Assumptions for Quantum Multiparty Secure Computations


  This paper introduces quantum multiparty protocols which allow the use of
temporary assumptions. We prove that secure quantum multiparty computations are
possible if and only if classical multi party computations work. But these
strict assumptions are necessary only during the execution of the protocol and
can be loosened after termination of the protocol.
  We consider two settings:
  1. A collusion of players tries to learn the secret inputs of honest players
or tries to modify the result of the computation.
  2. A collusion of players cheats in the above way or tries to disrupt the
protocol, i.e., the collusion tries to abort the computation or leaks
information to honest players. We give bounds on the collusions tolerable after
a protocol has terminated and we state protocols reaching these bounds.

</DOC>
<DOC>
<DOCNO> 9739 </DOCNO>
Comment on ``Scaling Laws for a System with Long-Range Interactions


  In their recent Letter [Phys. Rev. Lett. 83, 4233 (1999)], Salazar and Toral
(ST) study numerically a finite Ising chain with non-integrable interactions
decaying like 1/r^(d+sigma) where -d <= sigma <= 0 (like ST, we discuss general
dimensionality d). In particular, they explore a presumed connection between
non-integrable interactions and Tsallis's non-extensive statistics. We point
out that (i) non-integrable interactions provide no more motivation for Tsallis
statistics than do integrable interactions, i.e., Gibbs statistics remain
meaningful for the non-integrable case, and in fact provide a {\em complete and
exact treatment}; and (ii) there are undesirable features of the method ST use
to regulate the non-integrable interactions.

</DOC>
<DOC>
<DOCNO> 121189 </DOCNO>
Black hole masses from power density spectra: determinations and


  We analyze the scaling of the X-ray power density spectra with the mass of
the black hole on the example of Cyg X-1 and Seyfert 1 galaxy NGC 5548. We show
that the high frequency tail of the power density spectrum can be successfully
used for determination of the black hole mass. We determine the masses of the
black holes in 6 Broad Line Seyfert 1 galaxies, 5 Narrow Line Seyfert 1
galaxies and two QSOs using available power density spectra. The proposed
scaling is clearly appropriate for other Seyfert galaxies and QSOs. In all but
1 normal Seyferts the resulting luminosity to the Eddington luminosity ratio is
smaller than 0.15, with a source MCG -6-15-30 being an exception. The
applicability of the same scaling to Narrow Line Seyfert 1 is less clear and
there may be a systematic shift between the power spectra of NLS1 and S1
galaxies of the same mass, leading to underestimation of the black hole mass.
However, both the method based on variability and the method based on spectral
fitting show that those galaxies have relatively low masses and high luminosity
to the Eddington luminosity ratio, supporting the view of those objects as
analogs of galactic sources in their high/soft or very high state based on the
overall spectral shape. Bulge masses of their host galaxies are similar to
normal Seyfert galaxies so they do not follow the black hole mass-bulge mass
relation for Seyfert galaxies, being evolutionary less advanced, as suggested
by Mathur (2000). The bulge mass-black hole mass relation in our sample is
consistent with being linear, with black hole to bulge ratio $\sim$ 0.03 %,
similar to Wandel (1999) and Laor (1998, 2001) for low mass objects but
significantly shifted from the relation of Magorrian et al. (1998) and McLure &
Dunlop (2000).

</DOC>
<DOC>
<DOCNO> 121353 </DOCNO>
X-ray Properties of Groups of Galaxies


  ROSAT observations indicate that approximately half of all nearby groups of
galaxies contain spatially extended X-ray emission. The radial extent of the
X-ray emission is typically 50-500 kpc or approximately 10-50% of the virial
radius of the group. Diffuse X-ray emission is generally restricted to groups
that contain at least one early-type galaxy. X-ray spectroscopy suggests the
emission mechanism is most likely a combination of thermal bremsstrahlung and
line emission. This interpretation requires that the entire volume of groups be
filled with a hot, low-density gas known as the intragroup medium. Higher
temperature groups tend to follow the correlations found for rich clusters
between X-ray luminosity, temperature, and velocity dispersion. However, groups
with temperatures below approximately 1 keV appear to fall off the cluster L-T
relationship (and possibly the L-sigma and sigma-T cluster relationships,
although evidence for these latter departures is at the present time not very
strong.)

</DOC>
<DOC>
<DOCNO> 101772 </DOCNO>
Calculating maps between n-categories


  We give an explicit way of calculating the set of homotopy classes of
morphisms from a Tamsamani n-category A to another one B. This calculation uses
a Reedy-cofibrant cosimplicial resolution of A, using a new notion of ``free
cofibration'' of n-precats. The free cofibrations of n-precats seem to be the
analogue for n-categories of the Bousfield-Kan cofibrations in the theory of
diagrams.

</DOC>
<DOC>
<DOCNO> 11319 </DOCNO>
Heat and momentum transport in a multicomponent mixture far from


  Explicit expressions for the heat and momentum fluxes are given for a
low-density multicomponent mixture in a steady state with temperature and
velocity gradients. The results are obtained from a formally exact solution of
the Gross-Krook model [Phys. Rev. {\bf 102}, 593 (1956)] of the Boltzmann
equation for a multicomponent mixture. The transport coefficients (shear
viscosity, viscometric functions, thermal conductivity and a cross coefficient
measuring the heat flux orthogonal to the thermal gradient) are nonlinear
functions of the velocity and temperature gradients and the parameters of the
mixture (particle masses, concentrations, and force constants). The description
applies for conditions arbitrarily far from equilibrium and is not restricted
to any range of mass ratios, molar fractions and/or size ratios. The results
show that, in general, the presence of the shear flow produces an inhibition in
the transport of momentum and energy with respect to that of the Navier-Stokes
regime. In the particular case of particles mechanically equivalent and in the
tracer limit, previous results are recovered.

</DOC>
<DOC>
<DOCNO> 70385 </DOCNO>
Fermion Mass Hierarchies and Small Mixing Angles from Extra Dimensions


  In this paper we study renormalization-group evolutions of Yukawa matrices
enhanced by Kaluza-Klein excited modes and analyze their infrared fixed-point
structure. We derive necessary conditions to obtain hierarchies between
generations on the fixed point. These conditions restrict how the fields in the
models can extend to higher dimension. Several specific mechanisms to realize
the conditions are presented. We also take account of generation mixing effects
and find a scenario where the mixing angles become small at low energy even
with large initial values at high-energy scale. A toy model is shown to lead
realistic quark mass matrices.

</DOC>
<DOC>
<DOCNO> 71001 </DOCNO>
Density perturbations in the brane-world


  In Randall-Sundrum-type brane-world cosmologies, density perturbations
generate Weyl curvature in the bulk, which in turn backreacts on the brane via
stress-energy perturbations. On large scales, the perturbation equations
contain a closed system on the brane, which may be solved without solving for
the bulk perturbations. Bulk effects produce a non-adiabatic mode, even when
the matter perturbations are adiabatic, and alter the background dynamics. As a
consequence, the standard evolution of large-scale fluctuations in general
relativity is modified. The metric perturbation on large-scales is not constant
during high-energy inflation. It is constant during the radiation era, except
at most during the very beginning, if the energy is high enough.

</DOC>
<DOC>
<DOCNO> 170320 </DOCNO>
Hybrid quantum computing


  Necessary and sufficient conditions are given for the construction of a
hybrid quantum computer that operates on both continuous and discrete quantum
variables. Such hybrid computers are shown to be more efficient than
conventional quantum computers for performing a variety of quantum algorithms,
such as computing eigenvectors and eigenvalues.

</DOC>
<DOC>
<DOCNO> 8698 </DOCNO>
Interacting Neural Networks


  Several scenarios of interacting neural networks which are trained either in
an identical or in a competitive way are solved analytically. In the case of
identical training each perceptron receives the output of its neighbour. The
symmetry of the stationary state as well as the sensitivity to the used
training algorithm are investigated. Two competitive perceptrons trained on
mutually exclusive learning aims and a perceptron which is trained on the
opposite of its own output are examined analytically. An ensemble of
competitive perceptrons is used as decision-making algorithms in a model of a
closed market (El Farol Bar problem or Minority Game); each network is trained
on the history of minority decisions. This ensemble of perceptrons relaxes to a
stationary state whose performance can be better than random.

</DOC>
<DOC>
<DOCNO> 69037 </DOCNO>
On the generation and identification of optical Schr\"odinger cats


  We discuss the possibility of generating and detecting, by a tomographic
reconstruction of the Wigner function, a macroscopic superposition of two
coherent states. The superposition state is created using a conditioned
measurement on the polarisation of a probe photon entangled to a coherent
state. The entanglement is obtained using a Kerr cell inserted in a Mach-Zender
interferometer. Some hint about generation of GHZ states is given as well.

</DOC>
<DOC>
<DOCNO> 119539 </DOCNO>
Studies of the high luminosity quasar, PDS 456


  X-ray and multi-wavelength observations of the most luminous known local
(z<0.3) AGN, the recently discovered radio-quiet quasar PDS 456, are presented.
The spectral energy distribution shows that PDS 456 has a bolometric luminosity
of 1e47 erg/s, peaking in the UV. The X-ray spectrum obtained by ASCA and RXTE
shows considerable complexity. The most striking feature observed is a deep,
highly-ionised, iron K edge (8.7 keV, rest-frame), originating via reprocessing
from highly ionised material, possibly the inner accretion disk. PDS 456 was
found to be remarkably variable for its luminosity; in one flare the X-ray flux
doubled in just about 15 ksec. If confirmed this would be an unprecedented
event in a high-luminosity source, with a light-crossing time corresponding to
about 2RS. The implications are that either flaring occurs within the very
central regions, or else that PDS 456 is a super-Eddington or relativistically
beamed system.

</DOC>
<DOC>
<DOCNO> 116430 </DOCNO>
Temporary Acceleration of Electrons While Inside an Intense


  A free electron can temporarily gain a very significant amount of energy if
it is overrun by an intense electromagnetic wave. In principle, this process
would permit large enhancements in the center-of-mass energy of
electron-electron, electron-positron and electron-photon interactions if these
take place in the presence of an intense laser beam. Practical considerations
severely limit the utility of this concept for contemporary lasers incident on
relativistic electrons. A more accessible laboratory phenomenon is
electron-positron production via an intense laser beam incident on a gas.
Intense electromagnetic pulses of astrophysical origin can lead to very
energetic photons via bremsstrahlung of temporarily accelerated electrons.

</DOC>
<DOC>
<DOCNO> 121794 </DOCNO>
Models of Veritcal Disturbances in the Interstellar Medium


  This paper describes some interesting properties of waves in, and
oscillations of, the interstellar medium in the direction normal to the plane
of the Galaxy. Our purpose is to examine possible reasons for four observed
phenomena: the falling sky in the northern hemisphere; the apparent presence of
clouds in absorption spectra when a sightline is occupied primarily only by
warm intercloud gas; the peculiar structuring of spiral arms involving clumps,
spurs, and feathering; and the existence of an abundance of high stage ions far
off the plane of the Galaxy.
  We explored the reaction of the interstellar medium - in the vertical
direction only - to large imposed disturbances (initial displacements,
expansive velocities, and compressions), and to the introduction of small
amplitude waves via oscillation of the midplane. Our findings included: 1) the
anticipated growth in amplitude of high frequency waves with height; 2) the
four lowest normal modes for the oscillation of the atmosphere as a whole, as
functions of the height of the outer boundary; 3) the time for material to
`bounce' from one unusually dense state to the next as a function of height;
and 4) the tendency for the disk to develop a hot outer halo, either after the
passage of a single shock from a large event, or in response to a continuous
stream of small amplitude waves.

</DOC>
<DOC>
<DOCNO> 84429 </DOCNO>
Higher dimensional flat embeddings of (2+1) dimensional black holes


  We obtain the higher dimensional global flat embeddings of static, rotating,
and charged BTZ black holes. On the other hand, we also study the similar
higher dimensional flat embeddings of the (2+1) de Sitter black holes which are
the counterparts of the anti-de Sitter BTZ black holes. As a result, the
charged dS black hole is shown to be embedded in (3+2) GEMS, contrast to the
charged BTZ one having (3+3) GEMS structure.

</DOC>
<DOC>
<DOCNO> 101822 </DOCNO>
Rel\`evement galoisien des rev\^etements de courbes nodales


  Let R be a complete discrete valuation ring of mixed characteristics, with
algebraically closed residue field k. We study the existence problem of
equivariant liftings to R of Galois covers of nodal curves over k. Using
formal geometry, we show that this problem is actually a local one. We apply
this local-to-global principle to obtain new results concerning the existence
of such liftings.

</DOC>
<DOC>
<DOCNO> 118998 </DOCNO>
Rotation and activity in the solar-type stars of NGC 2547


  We present high resolution spectroscopy of a sample of 24 solar-type stars in
the young (15-40 Myr), open cluster, NGC 2547. We use our spectra to confirm
cluster membership in 23 of these stars, determine projected equatorial
velocities and chromospheric activity, and to search for the presence of
accretion discs. We have found examples of both fast (vsini>50kms) and slow
(vsini<10kms) rotators, but find no evidence for active accretion in any of the
sample. The distribution of projected rotation velocities is indistinguishable
from the slightly older IC 2391 and IC 2602 clusters, implying similar initial
angular momentum distributions and circumstellar disc lifetimes. The presence
of very slow rotators indicates that either long (10-40 Myr) disc lifetimes or
internal differential rotation are needed, or that NGC 2547 (and IC 2391/2602)
were born with more slowly rotating stars than are presently seen in even
younger clusters and associations. The solar-type stars in NGC 2547 follow a
similar rotation-activity relationship to that seen in older clusters. X-ray
activity increases until a saturation level is reached for vsini>15-20kms. We
are unable to explain why this saturation level, of log (L_x/L_bol)~-3.3, is a
factor of two lower than in other clusters, but rule out anomalously slow
rotation rates or uncertainties in X-ray flux calculations.

</DOC>
<DOC>
<DOCNO> 118645 </DOCNO>
The Kinematics of the Planetary Nebula Population in M94


  The planetary nebula populations of relatively nearby galaxies can be easily
observed and provide both a distance estimate and a tool with which dynamical
information can be obtained. Usually the requisite radial velocities are
obtained by multi-object spectroscopy once the planetary nebulae have been
located by direct imaging. Here we report on a technique for measuring
planetary nebula kinematics using the double-beam ISIS spectrograph at the
William Herschel Telescope in a novel slitless mode, which enables the
detection and radial velocity measurements to be combined into a single step.
The results on our first target, the Sab galaxy NGC 4736, allow the velocity
dispersion of the stellar population in a disk galaxy to be traced out to four
scale lengths for the first time and are consistent with a simple isothermal
sheet model.

</DOC>
<DOC>
<DOCNO> 119948 </DOCNO>
Radio galaxy selected clusters at high redshift and associated ERO


  Galaxy clusters at high redshift present a superb opportunity to study galaxy
evolution, with large galaxy samples at fixed distances. Several lines of
evidence point towards large formation redshifts and passive evolution for
cluster ellipticals. At redshifts larger than z~0.8, this picture rests on data
from only a handful of rich clusters. We have observed four potential clusters
to sample sparser environments in a critical redshift range, 0.8 < z < 1.2. We
compare the photometric evolution and radial density profiles in our clusters
with more massive clusters studied in a similar manner. We also highlight the
overdense ERO (I-K>5) population, significantly redder than the old elliptical
population at the cluster redshift. We discuss the implications of our clusters
at high redshift, and possible differences in environment from richer clusters
at similar redshifts selected through X-ray or optical techniques.

</DOC>
<DOC>
<DOCNO> 116966 </DOCNO>
2GeV Superconducting Muon Linac


  A muon collider as well as a neutrino factory requires a large number of
muons with a kinetic energy of 50GeV or more. Muon survival demands a high
gradient linac. The large transverse and longitudinal emittance of the muon
beam coming from a muon cooling system implies the need for a large acceptance,
acceleration system. These two requirements point clearly to a linac based on
superconducting technology. The design of a 2GeV Superconducting muon Linac
based on computer programs developed at LANL will be presented. The design is
based on the technology available today or components that will be avaible in
the very near future.

</DOC>
<DOC>
<DOCNO> 120533 </DOCNO>
X-ray Emission From Nearby M-dwarfs: the Super-saturation Phenomenon


  A rotation rate and X-ray luminosity analysis is presented for rapidly
rotating single and binary M-dwarf systems. X-ray luminosities for the majority
of both single & binary M-dwarf systems with periods below $\simeq 5-6$ days
(equatorial velocities, V$_{eq}>$ 6 km~s$^{-1}$) are consistent with the
current rotation-activity paradigm, and appear to saturate at about $10^{-3}$
of the stellar bolometric luminosity. The single M-dwarf data show tentative
evidence for the super-saturation phenomenon observed in some ultra-fast
rotating ($>$ 100 km~s$^{-1}$) G & K-dwarfs in the IC 2391, IC 2602 and Alpha
Persei clusters. The IC 2391 M star VXR60b is the least X-ray active and most
rapidly rotating of the short period (P$_{rot}<$ 2 days) stars considered
herein, with a period of 0.212 days and an X-ray activity level about 1.5 sigma
below the mean X-ray emission level for most of the single M-dwarf sample. For
this star, and possibly one other, we cautiously believe that we have
identified the first evidence of super-saturation in M-dwarfs. If we are wrong,
we demonstrate that only M-dwarfs rotating close to their break up velocities
are likely to exhibit the super-saturation effect at X-ray wavelengths.

</DOC>
<DOC>
<DOCNO> 100215 </DOCNO>
On the Frobenius integrability of certain holomorphic p-forms


  The goal of this note is to exhibit the integrability properties (in the
sense of the Frobenius theorem) of holomorphic p-forms with values in certain
line bundles with seminegative curvature on a compact Kaehler manifold. There
are in fact very strong restrictions, both on the holomorphic form and on the
curvature of the seminegative line bundle. As a consequence, these observations
provide interesting information on the structure of projective manifolds which
admit a contact structure: either they are Fano manifolds or, thanks to results
of Kebekus-Peternell-Sommese-Wisniewski, they are biholomorphic to the
projectivization of the cotangent bundle of another suitable projective
manifold.

</DOC>
<DOC>
<DOCNO> 68568 </DOCNO>
Magnetic moment of $\Delta^{++}$ baryon in QCD string approach


  Magnetic moment of the $\Delta^{++}$ baryon is computed within the new
approach based on the QCD string Hamiltonian.
   The string tension $\sigma$ is only dimensionful quantity forming magnetic
moments of both nucleon and $\Delta$, but color Coulomb and spin-spin
interactions cancel each other in the nucleon case while in $\Delta$ they add
coherently. The result $\mu_{\Delta} = 4.36\mu_N$ is in good agreement with
experimental data.

</DOC>
<DOC>
<DOCNO> 99545 </DOCNO>
Wave invariants at elliptic closed geodesics


  This paper concerns spectral invariants of the Laplacian on a compact
Riemannian manifold (M,g) known as wave invariants. If U(t) denotes the wave
group of (M,g), then the trace Tr U(t) is singular when t = 0 or when ti is the
length of a closed geodesic. It has a special type of singularity expansion at
each length and the coefficients are known as the wave invariants. Our main
purpose is to calculate the wave invariants explicitly in terms of curvature,
Jacobi fields etc. when the closed geodesic is non-degenerate elliptic. We do
this by putting the Laplacian into quantum Birkhoff normal form at the closed
geodesic. Such a normal form was previously introduced by V. Guillemin. We give
a new algorithm for calculating it, and for expressing wave invariants in terms
of normal form invariants.

</DOC>
<DOC>
<DOCNO> 117725 </DOCNO>
Measuring the Diffuse Optical Light in Abell 1651


  Using drift scan data, a new approach to determining surface brightness
profiles, and techniques for detecting low surface brightness signals, we fit
the light profile of the brightest cluster galaxy (BCG) in the rich cluster
Abell 1651 out to 670 h^{-1} kpc. This radius is a significant fraction of the
virial radius of the cluster (2 h^{-1} Mpc; Girardi et al. 1998), indicating
that the sizes of the BCG and the cluster are comparable. We find that the
profile is consistent with a de Vaucouleurs profile over the radial range
probed. We also find that the integrated light profile of the BCG in Abell 1651
contributes 36% of the total cluster light within 500 h^{-1} kpc. Including all
luminous components, we obtain M/L_I~160 h for the cluster, which would be
overestimated by ~20% without the BCG halo. Furthermore, the relatively red
color of the BCG at large radii suggests that recent disruption and tidal
stripping of spirals and dwarf ellipticals do not contribute significantly to
the halo luminosity. The color and the form of the profile are consistent with
a scenario in which the BCG forms from filamentary collapse during the epoch of
cluster formation, with relatively little evolution in the past 5 Gyrs
(Dubinski 1998). We remove the BCG and other detected galaxies from the image
and construct a two dimensional surface brightness map of the cluster core.
Several knots of excess emission are found, but the total diffuse component is
constrained to contribute less than 5% of the cluster light.

</DOC>
<DOC>
<DOCNO> 83235 </DOCNO>
Multiagent Control of Self-reconfigurable Robots


  We demonstrate how multiagent systems provide useful control techniques for
modular self-reconfigurable (metamorphic) robots. Such robots consist of many
modules that can move relative to each other, thereby changing the overall
shape of the robot to suit different tasks. Multiagent control is particularly
well-suited for tasks involving uncertain and changing environments. We
illustrate this approach through simulation experiments of Proteo, a
metamorphic robot system currently under development.

</DOC>
<DOC>
<DOCNO> 9218 </DOCNO>
Reflection and absorption of QWs irradiated by light pulses in a strong


  It has been shown that the non-sinusoidal character oscillations appear in
the transmitted, reflected and absorbed light fluxes when light pulses
irradiate a semiconductor quantum well (QW), containing a set of a large number
of the equidistant energy levels of electronic excitations. The oscillation
amplitude is comparable to the flux values for the short pulses, duration of
which \gamma_l^{-1} \leq \hbar/\Delta E. A damping echo of the exciting pulse
appears through the time intervals 2\pi\hbar/\Delta E in the case of the very
short light pulses \gamma_l^{-1}\ll \hbar/\Delta E. Symmetrical and
asymmetrical pulses with a sharp front have been considered. Our theory is
applicable for the narrow QWs in a strong magnetic field, when the equidistant
energy levels correspond to the electron-hole pairs with different Landau
quantum numbers.

</DOC>
<DOC>
<DOCNO> 169699 </DOCNO>
Coherent states sometimes look like squeezed states, and visa versa: The


  Using the Paul Trap as a model, we point out that the same wave functions can
be variously coherent or squeezed states, depending upon the system they are
applied to.

</DOC>
<DOC>
<DOCNO> 102233 </DOCNO>
Evolution equations for special Lagrangian 3-folds in C^3


  This is the third in a series of papers constructing explicit examples of
special Lagrangian submanifolds in C^m. The previous paper in the series,
math.DG/0008155, defined the idea of evolution data, which includes an
(m-1)-submanifold P in R^n, and constructed a family of special Lagrangian
m-folds N in C^m, which are swept out by the image of P under a 1-parameter
family of linear or affine maps phi_t : R^n -> C^m, satisfying a first-order
o.d.e. in t.
  In this paper we use the same idea to construct special Lagrangian 3-folds in
C^3. We find a 1-1 correspondence between sets of evolution data with m=3 and
homogeneous symplectic 2-manifolds P. This enables us to write down several
interesting sets of evolution data, and so to construct corresponding families
of special Lagrangian 3-folds in C^3.
  Our main results are a number of new families of special Lagrangian 3-folds
in C^3, which we write very explicitly in parametric form. Generically these
are nonsingular as immersed 3-submanifolds, and diffeomorphic to R^3 or S^1 x
R^2. Some of the 3-folds are singular, and we describe their singularities,
which we believe are of a new kind.
  We hope these 3-folds will be helpful in understanding singularities of
compact special Lagrangian 3-folds in Calabi-Yau 3-folds. This will be
important in resolving the SYZ conjecture in Mirror Symmetry.

</DOC>
<DOC>
<DOCNO> 101867 </DOCNO>
The homology of iterated loop spaces


  The singular chain complex of the iterated loop space is expressed in terms
of the cobar construction. After that we consider the spectral sequence of the
cobar construction and calculate its first term over Z/p-coefficients and over
a field of characteristic zero. Finally we apply these results to calculate the
homology of the iterated loop spaces of the stunted real and complex projective
spaces. In the Appendix, written by F.Sergeraert there are considered computer
methods for calculations of the homology of iterated loop spaces.

</DOC>
<DOC>
<DOCNO> 13998 </DOCNO>
Mechanism of Magnetism in Stacked Nanographite: Theoretical Study


  Antiferromagnetism in stacked nanographite is investigated with using the
Hubbard-type model. The A-B stacking is favorable for the hexagonal
nanographite with zigzag edges, in order that magnetism appears. Next, we find
that the open shell electronic structures can be origins of the decreasing
magnetic moment with the decrease of the inter-graphene distance, as
experiments on adsorption of molecules suggest.

</DOC>
<DOC>
<DOCNO> 84950 </DOCNO>
Notes on Riemann geometry and integrable systems. Part V


  Some aspects of multidimensional soliton geometry are considered.

</DOC>
<DOC>
<DOCNO> 121037 </DOCNO>
Variable Galaxies in the Hubble Deep Field


  We present results from a study to detect variable galaxies in the Hubble
Deep Field North. The goal of this project is to investigate the number density
of AGN at z=1 through the detection of variable galaxy nuclei. The advantage of
HST is the ability to do accurate photometry within smaller apertures, thus
allowing us to probe much lower AGN/host galaxy luminosity ratios than can be
done from the ground. The primary data sets analyzed for galactic variability
follow from the original HDF-N observations in December 1995 and a second epoch
obtained two years later.
  We have detected nuclear variability at or above the 3 sigma level in 8 of
633 HDF galaxies at I<27. Only 2 detections would be expected by chance in a
normal distribution. At least one of these 8 has been spectroscopically
confirmed as a Seyfert 1 galaxy. Based on the AGN structure function for
variability, the estimated luminosity of the varying component in each galaxy
lies in the range -19.5<M<-15.0. We construct an upper limit to the luminosity
function for the variable nuclei and compare this to the local Seyfert LF and
the LF for QSOs at z=1. Assuming we have detected all Seyfert-like nuclei in
the HDF-N, we find no evidence for an increase in the number density of AGN at
M=-19. We estimate that ~1-3% of field galaxies with I<27 may contain a nuclear
AGN.

</DOC>
<DOC>
<DOCNO> 151808 </DOCNO>
A no-go theorem for string warped compactifications


  We give necessary conditions for the existence of perturbative heterotic and
common sector type II string warped compactifications preserving four and eight
supersymmetries to four spacetime dimensions, respectively. In particular, we
find that the only compactifications of heterotic string with the spin
connection embedded in the gauge connection and type II strings are those on
Calabi-Yau manifolds with constant dilaton. We obtain similar results for
compactifications to six and to two dimensions.

</DOC>
<DOC>
<DOCNO> 151357 </DOCNO>
Quantum BRST properties of reparametrization invariant theories


  Any regular quantum mechanical system may be cast into an abelian gauge
theory by simply reformulating it as a reparametrization invariant theory. We
present a detailed study of the BRST quantization of such reparametrization
invariant theories within a precise operator version of BRST. The treatment
elucidates several intricate aspects of the BRST quantization of
reparametrization invariant theories like the appearance of physical time. We
propose general rules for how physical wave functions and physical propagators
are to be projected from the BRST singlets and propagators in the ghost
extended BRST theory. These projections are performed by boundary conditions
which are precisely specified by the operator BRST. We demonstrate explicitly
the validity of these rules for the considered class of models. The
corresponding path integrals are worked out explicitly and compared with the
conventional BFV path integral formulation.

</DOC>
<DOC>
<DOCNO> 119839 </DOCNO>
AU-Scale Synchrotron Jets and Superluminal Ejecta in GRS 1915+105


  Radio imaging of the microquasar GRS 1915+105 with the Very Long Baseline
Array (VLBA) during various flaring, quiescent, or oscillatory states of the
black hole binary, always resolves the nucleus as a compact jet of length about
10.lambda_cm AU. On scales of 2.5-7AU, the nucleus has brightness temperature
T_B > 10^9 K, and its properties are better fit by a synchrotron jet, rather
than a thermal jet. The nuclear jet varies in 10-60min during minor X-ray/radio
outbursts, and re-establishes within 18hrs of a major outburst, indicating the
robustness of the disk/jet system to disruption. At lower resolution
(80-240AU), time-lapse images reveal discrete superluminal ejecta at 500-600 AU
separation from the nucleus. The measured velocity is 1.5c+-0.1c(D/12 kpc) for
the approaching component, consistent with ballistic motion of the ejecta from
500AU outwards, perhaps even since birth. The axis of the ejecta differs by
<12deg clockwise from the axis of the AU-scale jet, measured in the same
observation. Both axes are stable for years. The black hole is astrometrically
located to +-1.5mas, after accounting for its secular parallax from Galactic
rotation of 5.8+-1.5mas/yr at the distance of 12kpc, and a limit of <100km/s is
placed on its proper-motion with respect to its neighbourhood. Our observations
suggest that the unresolved flat-spectrum radio cores of accreting black holes
are compact quasi-continuous synchrotron jets.

</DOC>
<DOC>
<DOCNO> 70581 </DOCNO>
Dilaton-gravity on the brane


  We derive the four-dimensional field equations for the induced metric and
scalar field on the world-volume of a 3-brane in a five-dimensional bulk with
Einstein gravity plus a self-interacting scalar field. We calculate the
effective four-dimensional gravitational constant and cosmological constant for
arbitrary forms of the brane tension and self-interaction potential for the
scalar field in the bulk. In addition to the canonical energy-momentum tensor
for the scalar field and ordinary matter on the brane, the effective
four-dimensional Einstein equations include terms due to the scalar field and
gravitational waves in the bulk. We present solutions corresponding to static
Minkowski brane worlds and also dynamical Friedmann-Robertson-Walker brane
world cosmologies. We discuss the induced coupling of the scalar field to
ordinary matter on the brane.

</DOC>
<DOC>
<DOCNO> 117455 </DOCNO>
Nature of microstructure in pulsar radio emission


  We present a model for microstructure in pulsar radio emission. We propose
that micropulses result from the alteration of the radio wave generation region
by nearly transverse drift waves propagating across the pulsar magnetic field
and encircling the bundle of the open magnetic field lines. It is demonstrated
that such waves can modify significantly curvature of these dipolar field
lines. This in turn affects strongly fulfillment of the resonance conditions
necessary for the excitation of radio waves. The time-scale of micropulses is
therefore determined by the wavelength of drift waves. Main features of the
microstructure are naturally explained in the frame of this model.

</DOC>
<DOC>
<DOCNO> 83110 </DOCNO>
Abductive and Consistency-Based Diagnosis Revisited: a Modeling


  Diagnostic reasoning has been characterized logically as consistency-based
reasoning or abductive reasoning. Previous analyses in the literature have
shown, on the one hand, that choosing the (in general more restrictive)
abductive definition may be appropriate or not, depending on the content of the
knowledge base [Console&Torasso91], and, on the other hand, that, depending on
the choice of the definition the same knowledge should be expressed in
different form [Poole94].
  Since in Model-Based Diagnosis a major problem is finding the right way of
abstracting the behavior of the system to be modeled, this paper discusses the
relation between modeling, and in particular abstraction in the model, and the
notion of diagnosis.

</DOC>
<DOC>
<DOCNO> 83286 </DOCNO>
Constraint Exploration and Envelope of Simulation Trajectories


  The implicit theory that a simulation represents is precisely not in the
individual choices but rather in the 'envelope' of possible trajectories - what
is important is the shape of the whole envelope. Typically a huge amount of
computation is required when experimenting with factors bearing on the dynamics
of a simulation to tease out what affects the shape of this envelope. In this
paper we present a methodology aimed at systematically exploring this envelope.
We propose a method for searching for tendencies and proving their necessity
relative to a range of parameterisations of the model and agents' choices, and
to the logic of the simulation language. The exploration consists of a forward
chaining generation of the trajectories associated to and constrained by such a
range of parameterisations and choices. Additionally, we propose a
computational procedure that helps implement this exploration by translating a
Multi Agent System simulation into a constraint-based search over possible
trajectories by 'compiling' the simulation rules into a more specific form,
namely by partitioning the simulation rules using appropriate modularity in the
simulation. An example of this procedure is exhibited.
  Keywords: Constraint Search, Constraint Logic Programming, Proof, Emergence,
Tendencies

</DOC>
<DOC>
<DOCNO> 71915 </DOCNO>
Quark description of nuclear matter


  We discuss the role of an adjoint chiral condensate for color superconducting
quark matter. Its presence leads to color-flavor locking in two-flavor quark
matter. Color is broken completely as well as chiral symmetry in the two-flavor
theory with coexisting adjoint quark-antiquark and antitriplet quark-quark
condensates. The qualitative properties of this phase match the properties of
ordinary nuclear matter without strange baryons. This complements earlier
proposals by Schafer and Wilczek for a quark description of hadronic phases. We
show for a class of models with effective four-fermion interactions that
adjoint chiral and diquark condensates do not compete, in the sense that
simultaneous condensation occurs for sufficiently strong interactions in the
adjoint chiral channel.

</DOC>
<DOC>
<DOCNO> 12253 </DOCNO>
Andreev-Tunneling, Coulomb Blockade, and Resonant Transport of Non-Local


  We propose and analyze a spin-entangler for electrons based on an s-wave
superconductor coupled to two quantum dots each of which is tunnel-coupled to
normal Fermi leads. We show that in the presence of a voltage bias and in the
Coulomb blockade regime two correlated electrons provided by the Andreev
process can coherently tunnel from the superconductor via different dots into
different leads. The spin-singlet coming from the Cooper pair remains preserved
in this process, and the setup provides a source of mobile and nonlocal
spin-entangled electrons. The transport current is calculated and shown to be
dominated by a two-particle Breit-Wigner resonance which allows the injection
of two spin-entangled electrons into different leads at exactly the same
orbital energy, which is a crucial requirement for the detection of spin
entanglement via noise measurements. The coherent tunneling of both electrons
into the same lead is suppressed by the on-site Coulomb repulsion and/or the
superconducting gap, while the tunneling into different leads is suppressed
through the initial separation of the tunneling electrons. In the regime of
interest the particle-hole excitations of the leads are shown to be negligible.
The Aharonov-Bohm oscillations in the current are shown to contain single- and
two-electron periods with amplitudes that both vanish with increasing Coulomb
repulsion albeit differently fast.

</DOC>
<DOC>
<DOCNO> 71104 </DOCNO>
New features of FORM


  Version 3 of FORM is introduced. It contains many new features that are
inspired by current developments in the methodology of computations in quantum
field theory. A number of these features is discussed in combination with
examples. In addition the distribution contains a number of general purpose
packages. These are described shortly.

</DOC>
<DOC>
<DOCNO> 69478 </DOCNO>
Hierarchical Radiative Quark Mass Matrices with an $U(1)_X$ Horizontal


  In a model with a gauge group $G_{SM}\otimes U(1)_X$, where $G_{SM} \equiv
SU(3)_C \otimes SU(2)_L \otimes U(1)_Y$ is the standard model gauge group and
$U(1)_X$ is a horizontal local gauge symmetry, we propose a radiative
generation of the spectrum of quark masses and mixing angles. The assignment of
horizontal charges is such that at tree level only the third family is massive.
Using these tree level masses and introducing exotic scalars, the light
families of quarks acquire hierarchical masses through radiative corrections.
The rank three quark mass matrices obtained are written in terms of a minimal
set of free parameters of the model, whose values are estimated performing a
numerical fit. The resulting quark masses and CKM mixing angles turn out to be
in good agreement with the experimental values.

</DOC>
<DOC>
<DOCNO> 99590 </DOCNO>
Analysis of Experimental Investigations of Self-Similar Intermediate


  Analysis of the Stockholm group data on zero-pressure-gradient boundary
flows, presented in the thesis of J.~M.~\"Osterlund ({\tt
http://www.mesh.kth.se/$\sim$jens/zpg/}) is performed. The results of
processing of all 70 mean velocity profiles are presented. It is demonstrated
that, properly processed, these data lead to a conclusion opposite from that of
the thesis and related papers: they confirm the Reynolds-number-dependent
scaling law and disprove the conclusion that the flow in the intermediate
("overlap") region is Reynolds-number-independent.

</DOC>
<DOC>
<DOCNO> 83219 </DOCNO>
On the Scalability of the Answer Extraction System "ExtrAns"


  This paper reports on the scalability of the answer extraction system
ExtrAns. An answer extraction system locates the exact phrases in the documents
that contain the explicit answers to the user queries. Answer extraction
systems are therefore more convenient than document retrieval systems in
situations where the user wants to find specific information in limited time.
  ExtrAns performs answer extraction over UNIX manpages. It has been
constructed by combining available linguistic resources and implementing only a
few modules from scratch. A resolution procedure between the minimal logical
form of the user query and the minimal logical forms of the manpage sentences
finds the answers to the queries. These answers are displayed to the user,
together with pointers to the respective manpages, and the exact phrases that
contribute to the answer are highlighted.
  This paper shows that the increase in response times is not a big issue when
scaling the system up from 30 to 500 documents, and that the response times for
500 documents are still acceptable for a real-time answer extraction system.

</DOC>
<DOC>
<DOCNO> 80816 </DOCNO>
Simulations in SO(3) \times Z(2) lattice gauge theory


  We explore simulations on periodic lattices in the Tomboulis $SO(3) \times
Z(2)$ formulation. We measure gauge invariant vortex counters for "thin",
"thick" and "hybrid" vortex sheets in order to tag Wilson loops by the
occurance of gauge invariant vortices linking them. We also measure projection
vortex counters defined in the maximal center gauge for comparison.

</DOC>
<DOC>
<DOCNO> 69498 </DOCNO>
Fractal Electromagnetic Showers


  We study the self-similar structure of electromagnetic showers and introduce
the notion of the fractal dimension of a shower. Studies underway of showers in
various materials and at various energies are presented, and the range over
which the fractal scaling behaviour is observed is discussed. Applications to
fast shower simulations and identification, particularly in the context of
extensive air showers, are also discussed.

</DOC>
<DOC>
<DOCNO> 121465 </DOCNO>
Astrophysical Quantities of Cepheid Variables Measured with the NPOI


  We present mean angular diameters for two cepheid variables, alpha Ursae
Minoris and zeta Geminorum, determined with the Navy Prototype Optical
Interferometer (NPOI). We present linear radii for these cepheids and two
additional cepheids, delta Cephei and eta Aquilae, previously observed at the
NPOI. We find the limb-darkened angular diameter of alpha Ursae Minoris and of
zeta Geminorum to be 3.28 +/- 0.02 and 1.55 +/- 0.09 milliarcseconds
respectively. Using trigonometric parallaxes, we find the linear radii of alpha
Ursae Minoris, zeta Geminorum, delta Cephei and eta Aquilae to be 46 (+/- 3),
60 (+25, -14), 45 (+8, -6), and 69 (+28, -15) Solar radii respectively. We
compare the pulsation periods and linear radii of this sample of cepheids,
which range in period from three to 11 days, to theoretical and empirical
period-radius and period-radius-mass relations found in the literature. We find
that the observed diameter of alpha Ursae Minoris is in excellent agreement
with the predicted diameter as determined from both surface brightness
techniques and theory only if alpha Ursae Minoris is a first overtone pulsator.

</DOC>
<DOC>
<DOCNO> 117172 </DOCNO>
Aromatic Hydrocarbons, Diamonds, and Fullerenes in Interstellar Space:


  New research is presented, and previous research is reviewed, on the emission
and absorption of interstellar aromatic hydrocarbons. Emission from aromatic
hydrocarbons dominate the mid-infrared emission of many galaxies, including our
own Milky Way galaxy. Only recently have aromatic hydrocarbons been observed in
absorption in the interstellar medium, along lines of sight with high column
densities of interstellar gas and dust. Much work on interstellar aromatics has
been done, with astronomical observations and laboratory and theoretical
astrochemistry. In many cases the predictions of laboratory and theoretical
work are confirmed by astronomical observations, but in other cases clear
discrepancies exist which provide problems to be solved by a combination of
astronomical observations, laboratory studies, and theoretical studies. The
emphasis of this paper will be on current outstanding puzzles concerning
aromatic hydrocarbons which require further laboratory and theoretical
astrochemistry to resolve. This paper will also touch on related topics where
laboratory and theoretical astrochemistry studies are needed to explain
astrophysical observations, such as a possible absorption feature due to
interstellar "diamonds" and the search for fullerenes in space.

</DOC>
<DOC>
<DOCNO> 70524 </DOCNO>
Supersymmetric Superconducting Bag as a Core of Kerr Spinning Particle


  The problem of a regular matter source for the Kerr spinning particle is
discussed. A class of minimal deformations of the Kerr-Newman solution is
considered obeying the conditions of regularity and smoothness for the metric
and its matter source.
  It is shown that for charged source corresponding matter forms a rotating
bag-like core having (A)dS interior and smooth domain wall boundary. Similarly,
the requirement of regularity of the Kerr-Newman electromagnetic field leads to
superconducting properties of the core.
  We further consider the U(I) x U'(I) field model (which was used by Witten to
describe cosmic superconducting strings), and we show that it can be adapted
for description of superconducting bags having a long range external
electromagnetic field and another gauge field confined inside the bag.
Supersymmetric version of the Witten field model given by Morris is analyzed,
and corresponding BPS domain wall solution interpolating between the outer and
internal supersymmetric vacua is considered. The charged bag bounded by this
BPS domain wall represents an `ultra-extreme' state with a total mass which is
lower than BPS bound of the wall. It is also shown that supergravity suggests
the AdS vacuum state inside the bag.
  Peculiarities of this model for the rotating bag-like source of the
Kerr-Newman geometry are discussed.

</DOC>
<DOC>
<DOCNO> 84956 </DOCNO>
Tumbleweeds and airborne gravitational noise sources for LIGO


  Gravitational-wave detectors are sensitive not only to astrophysical
gravitational waves, but also to the fluctuating Newtonian gravitational forces
of moving masses in the ground and air around the detector. This paper studies
the gravitational effects of density perturbations in the atmosphere, and from
massive airborne objects near the detector. These effects were previously
considered by Saulson; in this paper I revisit these phenomena, considering
transient atmospheric shocks, and the effects of sound waves or objects
colliding with the ground or buildings around the test masses. I also consider
temperature perturbations advected past the detector as a source of
gravitational noise. I find that the gravitational noise background is below
the expected noise floor even of advanced interferometric detectors, although
only by an order of magnitude for temperature perturbations carried along
turbulent streamlines. I also find that transient shockwaves in the atmosphere
could potentially produce large spurious signals, with signal-to-noise ratios
in the hundreds in an advanced interferometric detector. These signals could be
vetoed by means of acoustic sensors outside of the buildings. Massive
wind-borne objects such as tumbleweeds could also produce gravitational signals
with signal-to-noise ratios in the hundreds if they collide with the
interferometer buildings, so it may be necessary to build fences preventing
such objects from approaching within about 30m of the test masses.

</DOC>
<DOC>
<DOCNO> 121295 </DOCNO>
Relation between blue/UV continuum shape and the ratio of radio to


  The low frequency radio luminosity is believed to be an indicator of jet
power, while the optical/UV emission is probably from accretion discs in the
nuclei of steep-spectrum radio quasars. We present a correlation between the
ratio of radio to optical luminosities and the continuum spectral index in
blue/UV bands, which might indicate that the continuum shape in blue/UV bands
is related to the ratio of jet to accretion power. The results may imply that
the spectra and structure of accretion discs are probably affected by the
interactions between jets and discs.

</DOC>
<DOC>
<DOCNO> 70413 </DOCNO>
Spontaneously broken color


  The vacuum of QCD is characterized by the Higgs mechanism. Color is
``spontaneously broken'' by a quark-antiquark condensate in the octet
representation. The massive gluons carry integer electric charges and are
identified with the vector mesons. The fermionic excitations consist of the low
mass baryon octet and a singlet. The interactions between these particles and
the light pseudoscalar octet are largely determined by chiral symmetry and a
nonlinear local symmetry. A consistent phenomenological picture of strong
interactions at long distances arises from a simple effective action.

</DOC>
<DOC>
<DOCNO> 7806 </DOCNO>
Islands, craters, and a moving surface step on a hexagonally


  Deposition/removal of metal atoms on the hex reconstructed (100) surface of
Au, Pt and Ir should present intriguing aspects, since a new island implies hex
-> square deconstruction of the substrate, and a new crater the square -> hex
reconstruction of the uncovered layer. To obtain a microscopic understanding of
how islands/craters form in these conditions, we have conducted simulations of
island and crater growth on Au(100), whose atomistic behavior, including the
hex reconstruction on top of the square substrate, is well described by mean s
of classical many-body forces. By increasing/decreasing the Au coverage on
Au(100), we find that island/craters will not grow unless they exceed a
critical size of about 8-10 atoms. This value is close to that which explains
the nonlinear coverage dependence observed in molecular adsorption on the
closely related surface Pt (100). This threshold size is rationalized in terms
of a transverse step correlation length, measuring the spatial extent where
reconstruction of a given plane is disturbed by the nearby step.

</DOC>
<DOC>
<DOCNO> 116956 </DOCNO>
Analysis and Synthesis of the SNS Superconducting RF Control System


  The RF system for the SNS superconducting linac consists of a superconducting
cavity, a klystron, and a low-level RF (LLRF) control system. For a proton
linac like SNS, the field in each individual cavity needs to be controlled to
meet the overall system requirements. The purpose of the LLRF control system is
to maintain the RF cavity field to a desired magnitude and phase by controlling
the klystron driver signal. The Lorentz force detuning causes the shift of the
resonant frequency during the normal operation in the order of a few hundreds
hertz. In order to compensate the Lorentz force detuning effects, the cavity is
pre-tuned into the middle of the expected frequency shift caused by the Lorentz
force detuning. Meanwhile, to reduce the overshoot in the transient response, a
feed-forward algorithm, a linear parameter varying gain scheduling (LPV-GS)
controller, is proposed to get away a repetitive noised caused by the pulsed
operation as well as the Lorentz force detuning effects.

</DOC>
<DOC>
<DOCNO> 84877 </DOCNO>
Entropy gap and time asymmetry II


  In this letter the paper [R. Aquilano, M. Castagnino, Mod. Phys. Lett A,11,
755 (1996)] is improved by considering that the main source of entropy
production are the stars photospheres.

</DOC>
<DOC>
<DOCNO> 117353 </DOCNO>
The variability analysis of PKS 2155-304


  In this paper, the post-1977 photometric observations of PKS 2155-304 are
compiled and used to discuss the variation periodicity. Largest amplitude
variations ($\Delta U = 1^{m}.5$; $\Delta B = 1^{m}.65$;
  $\Delta V = 1^{m}.85 $; $\Delta R = 1^{m}.25$; $\Delta I = 1^{m}.14 $) and
color indices ($(B-V) = 0.30\pm 0.06$; $(U-B) = -0.72\pm 0.08$;
  $(B-R) = 0.62\pm 0.07$; $(V-R) = 0.32\pm 0.04$) are found.
  The Jurkevich's method and DCF (Discrete Correlation Function) method
indicate possible periods of 4.16-year and 7.0-year in the V light curve.

</DOC>
<DOC>
<DOCNO> 101288 </DOCNO>
Stationary random fields with linear regressions


  We analyze certain stationary fields with linear regressions and quadratic
conditional variances. This classic probabilistic problem leads somewhat
unexpectedly to stationary Markov processes closely tied to non-commutative
probability through the q-Hermite polynomials.

</DOC>
<DOC>
<DOCNO> 84620 </DOCNO>
Thick Domain Walls Intersecting a Black Hole


  We discuss the gravitationally interacting system of a thick domain wall and
a black hole. We numerically solve the scalar field equation in the
Schwarzschild spacetime and show that there exist scalar field configurations
representing thick domain walls intersecting the black hole.

</DOC>
<DOC>
<DOCNO> 13808 </DOCNO>
Molecular dynamics simulations of lead clusters


  Molecular dynamics simulations of nanometer-sized lead clusters have been
performed using the Lim, Ong and Ercolessi glue potential (Surf. Sci. {\bf
269/270}, 1109 (1992)). The binding energies of clusters forming crystalline
(fcc), decahedron and icosahedron structures are compared, showing that fcc
cuboctahedra are the most energetically favoured of these polyhedral model
structures. However, simulations of the freezing of liquid droplets produced a
characteristic form of ``shaved'' icosahedron, in which atoms are absent at the
edges and apexes of the polyhedron. This arrangement is energetically favoured
for 600-4000 atom clusters. Larger clusters favour crystalline structures.
Indeed, simulated freezing of a 6525-atom liquid droplet produced an imperfect
fcc Wulff particle, containing a number of parallel stacking faults. The
effects of temperature on the preferred structure of crystalline clusters below
the melting point have been considered. The implications of these results for
the interpretation of experimental data is discussed.

</DOC>
<DOC>
<DOCNO> 100240 </DOCNO>
Discrete Lagrangian Systems on Graphs. Symplecto-Topological Properties


  Discrete Lagrangian Systems on graphs are considered. Vector-valued closed
differential 2-form on the space of solutions is constructed. This form takes
values in the first homology group of the graph. This construction generalizes
the Symplectic Wronskian for the linear self-adjoint operators on graphs found
in 1997 by the first author and used for the needs of the Scattering Theory for
graphs with tails

</DOC>
<DOC>
<DOCNO> 70120 </DOCNO>
Non-perturbative effects in the W and Z transverse momentum distribution


  We use the "dispersive method" to investigate non-perturbative effects in the
transverse momentum distribution of vector bosons produced in p-pbar
collisions. The assumption of a non-perturbative modification to the running
coupling at low scales leads to additional contributions in impact parameter
space proportional to -b^2 log Q^2 and -b^2. Our results, which we expect to be
valid provided tau is not close to 1, are shown to account for a substantial
proportion of the total non-perturbative contribution extracted from data.

</DOC>
<DOC>
<DOCNO> 10016 </DOCNO>
Reading the three-dimensional structure of a protein from its amino acid


  While all the information required for the folding of a protein is contained
in its amino acid sequence, one has not yet learnt how to extract this
information so as to predict the detailed, biological active, three-dimensional
structure of a protein whose sequence is known. This situation is not
particularly satisfactory, in keeping with the fact that while linear
sequencing of the amino acids specifying a protein is relatively simple to
carry out, the determination of the folded-native-conformation can only be done
by an elaborate X-ray diffraction analysis performed on crystals of the protein
or, if the protein is very small, by nuclear magnetic resonance techniques.
Using insight obtained from lattice model simulations of the folding of small
proteins (fewer than 100 residues), in particular of the fact that this
phenomenon is essentially controlled by conserved contacts among strongly
interacting amino acids, which also stabilize local elementary structures
formed early in the folding process and leading to the (post-critical) folding
core when they assemble together, we have worked out a successful strategy for
reading the three-dimensional structure of a notional protein from its amino
acid sequence.

</DOC>
<DOC>
<DOCNO> 151412 </DOCNO>
Enveloping algebra valued gauge transformations for non-abelian gauge


  An enveloping algebra valued gauge field is constructed, its components are
functions of the Lie algebra valued gauge field and can be constructed with the
Seiberg-Witten map. This allows the formulation of a dynamics for a finite
number of gauge field components on non-commutative spaces.

</DOC>
<DOC>
<DOCNO> 170520 </DOCNO>
Reply to "On Stapp's`Nonlocal Character of Quantum Theory' "


  The question raised by Shimony and Stein is examined and used to explain in
more detail a key point of my proof that any theory that conforms to certain
general ideas of orthodox relativistic quantum field theory must permit
transfers of information over spacelike intervals. It is also explained why
this result is not a problem for relativistic quantum theory, but, on the
contrary, opens the door to a satisfactory realistic relativistic quantum
theory based on the ideas of Tomonaga, Schwinger, and von Neumann.

</DOC>
<DOC>
<DOCNO> 102155 </DOCNO>
Symplectic Floer homology and the mapping class group


  We consider symplectic Floer homology in the lowest nontrivial dimension,
that is to say, for area-preserving diffeomorphisms of surfaces. Particular
attention is paid to the quantum cap product; we show that it distinguishes the
trivial element of the mapping class group from any nontrivial one.

</DOC>
<DOC>
<DOCNO> 118758 </DOCNO>
The Alignment of Clusters using Large Scale Simulations


  The alignment of clusters of galaxies with their nearest neighbours and
between clusters within a supercluster is investigated using simulations of
512^{3} dark matter particles for \LambdaCDM and \tauCDM cosmological models.
Strongly significant alignments are found for separations of up to 15h^{-1}Mpc
in both cosmologies, but for the \LambdaCDM model the alignments extend up to
separations of 30h^{-1}Mpc. The effect is strongest for nearest neighbours, but
is not significant enough to be useful as an observational discriminant between
cosmologies. As a check of whether this difference in alignments is present in
other cosmologies, smaller simulations with 256^{3} particles are investigated
for 4 different cosmological models. Because of poor number statistics, only
the standard CDM model shows indications of having different alignments from
the other models.

</DOC>
<DOC>
<DOCNO> 71774 </DOCNO>
CP Violation for Leptons at Higher Energy Scales


  The phase convention independent measure of CP violation for three
generations of leptons is evaluated at different energy scales. Unlike in the
quark sector, this quantity does not vary much between the weak and the grand
unification scales. The behavior of the measure of CP violation in the Standard
Model is found to be different from that in the extensions of the Standard
Model.

</DOC>
<DOC>
<DOCNO> 119338 </DOCNO>
Hot and Cold Dark Matter Search with GENIUS


  GENIUS is a proposal for a large volume detector to search for rare events.
An array of 40-400 'naked' HPGe detectors will be operated in a tank filled
with ultra-pure liquid nitrogen. After a description of performed technical
studies of detector operation in liquid nitrogen and of Monte Carlo simulations
of expected background components, the potential of GENIUS for detecting WIMP
dark matter, the neutrinoless double beta decay in 76-Ge and low-energy solar
neutrinos is discussed.

</DOC>
<DOC>
<DOCNO> 13136 </DOCNO>
Boundary conditions at a fluid - solid interface


  We study the boundary conditions at a fluid-solid interface using molecular
dynamics simulations covering a broad range of fluid-solid interactions and
fluid densities, and both simple and chain-molecule fluids. The slip length is
shown to be independent of the type of flow, but rather is related to the fluid
organization near the solid, as governed by the fluid-solid molecular
interactions.

</DOC>
<DOC>
<DOCNO> 102910 </DOCNO>
Topological Open P-Branes


  By exploiting the BV quantization of topological bosonic open membrane, we
argue that flat 3-form C-field leads to deformations of the algebras of
multi-vectors on the Dirichlet-brane world-volume as 2-algebras. This would
shed some new light on geometry of M-theory 5-brane and associated decoupled
theories. We show that, in general, topological open p-brane theory has a
structure of (p+1)-algebra in the bulk, while a structure of p-algebra in the
boundary. The bulk/boundary correspondences are exactly as the generalized
Deligne conjecture (a theorem of Kontsevich) in the algebraic world of
p-algebras. It also imply that the algebras of quantum observables of
(p-1)-brane are ``close to'' the algebras of its classical observables as
p-algebras. We interpret above as deformation quantization of (p-1)-brane,
generalizing the p=1 case. We argue that there is such quantization based on
the direct relation between BV master equation and Ward identity of the bulk
topological theory. The path integral of the theory will lead to the explicit
formula. We also discuss some applications to topological strings and
conjecture that the homological mirror symmetry has further generalizations to
the categories of p-algebras.

</DOC>
<DOC>
<DOCNO> 99525 </DOCNO>
Kadec-Pelczynski decomposition for Haagerup L_p-spaces


  Let M be a von Neumann algebra (not necessarily semi-finite). We provide a
generalization of the classical Kadec-Pelczynski subsequence decomposition of
bounded sequences in L^p[0,1] to the case of the Haagerup L^p-spaces (1\le
p<\infty). In particular, we prove that if (\phi_n)_n is a bounded sequence in
the predual M_* of M, then there exist a subsequence (\phi_{n_k})_k of
(\phi_n)_n, a decomposition \phi_{n_k}= y_k+ z_k such that {y_k, k\ge 1} is
relatively weaklycompact and the support projections s(z_k)\downarrow_k 0 (or
similarly mutually disjoint). As an application, we prove that every
non-reflexive subspace of the dual of any given C*-algebra (or Jordan triples)
contains asymptotically isometric copies of l_1 and therefore fails the fixed
point property for nonexpansive mappings. These generalize earlier results for
the case of preduals of semi-finite von Neumann algebras.

</DOC>
<DOC>
<DOCNO> 102561 </DOCNO>
Arithmetical Aspects of Beurling's Real Variable Reformulation of the


  The paper presents two arithmetical versions of the Nyman-Beurling
equivalence with the Riemann hypothesis, proved by classical, quasi elementary,
number-theoretic methods, based on an integrated version of the classical
combinatorial identity for Moebius numbers. These proofs also give insight into
the troublesome phenomenon that many natural sequences of Beurling functions
tending to the indicator function of (0,1) both pointwise and in L1 norm do not
converge in L2 norm.

</DOC>
<DOC>
<DOCNO> 178931 </DOCNO>
Probing meson spectral functions with double differential dilepton


  The double differential dilepton spectrum $dN/ (dM_\perp^2 dM^2)$ at fixed
transverse mass $M_\perp$ allows a direct access to the vector meson spectral
functions. Within a fireball model the sensitivity of $dN/ (dM_\perp^2 dM^2)$
against variations of both the in-medium properties of mesons and the dynamics
of the fireball is investigated. In contrast to the integrated invariant-mass
spectrum $dN/dM^2$, in the spectrum $dN/dM^2 dM_\perp^2$ with fixed $M_\perp$
the $\omega$ signal is clearly seen as bump riding on the $\rho$ background
even in case of strong in-medium modifications.

</DOC>
<DOC>
<DOCNO> 121472 </DOCNO>
A Compact Population of Red Giants in the Blue Compact Dwarf Galaxy UGCA


  We present HST/WFPC2 single-star photometry for the blue dwarf galaxy UGCA
290, whose morphology is intermediate between classic iE Blue Compact Dwarfs
and blue dwarfs which exhibit no red background sheet of older stars. The
color-magnitude diagram of this galaxy in V and I, extending over six
magnitudes, is remarkably similar to that of the star-forming region in the iE
Blue Compact Dwarf VII Zw 403. There is no evidence for gaps in its
star-formation history over the last billion years, and the color of its red
giant branch indicates a very metal-poor stellar population. From the magnitude
of the tip of the red giant branch, we derive a distance of 6.7 Mpc, more than
twice the distance estimated from the brightest blue supergiants.

</DOC>
<DOC>
<DOCNO> 12417 </DOCNO>
Analytical results for generalized persistence properties of smooth


  We present a general scheme to calculate within the independent interval
approximation generalized (level-dependent) persistence properties for
processes having a finite density of zero-crossings. Our results are especially
relevant for the diffusion equation evolving from random initial conditions,
one of the simplest coarsening systems. Exact results are obtained in certain
limits, and rely on a new method to deal with constrained multiplicative
processes. An excellent agreement of our analytical predictions with direct
numerical simulations of the diffusion equation is found.

</DOC>
<DOC>
<DOCNO> 84605 </DOCNO>
Monopole Black Hole Skyrmions


  Charged black hole solutions with pion hair are discussed. These can be used
to study monopole black hole catalysis of proton decay. There also exist multi-
black hole skyrmion solutions with BPS monopole behavior.

</DOC>
<DOC>
<DOCNO> 8376 </DOCNO>
Fermi's golden rule in a mesoscopic metal ring


  We examine the time-dependent non-equilibrium current in a mesoscopic metal
ring threaded by a static magnetic flux phi that is generated by a
time-dependent electric field oscillating with frequency omega. We show that in
quadratic order in the field there are three fundamentally different
contributions to the current. (a) A time-independent contribution which can be
obtained from a thermodynamic derivative. (b) A term increasing linearly in
time that can be understood in terms of Fermi's golden rule. The derivation of
this term requires a careful treatment of the infinitesimal imaginary parts
that are added to the real frequency omega when the electric field is
adiabatically switched on. (c) Finally, there is also a time-dependent current
oscillating with frequency 2 omega. We suggest an experiment to test our
results.

</DOC>
<DOC>
<DOCNO> 117399 </DOCNO>
The First Galaxies: Clues from Element Abundances


  It has recently become possible to measure directly the abundances of several
chemical elements in a variety of environments at redshifts up to z = 5. In
this review I summarise the latest observations of Lyman break galaxies, damped
Lyman alpha systems and the Lyman alpha forest with a view to uncovering any
clues which these data may offer to the first episodes of star formation. The
picture which is emerging is one where the universe at z = 3 already included
many of the components of today's galaxies--even at these early times we see
evidence for Populations I and II stars, while the `smoking gun' for Population
III objects may be hidden in the chemical composition of the lowest density
regions of the IGM, yet to be deciphered.

</DOC>
<DOC>
<DOCNO> 170202 </DOCNO>
Analytic Expression for Exact Ground State Energy Based on an Operator


  A general procedure based on shift operators is formulated to deal with
anharmonic potentials. It is possible to extract the ground state energy
analytically using our method provided certain consistency relations are
satisfied. Analytic expressions for the exact ground state energy have also
been derived specifically for a large class of the one-dimensional oscillator
with cubic-quartic anharmonic terms. Our analytical results can be used to
check the accuracy of existing numerical methods, for instance the method of
state-dependent diagonalization. Our results also agree with the asymptotic
behavior in the divergent pertubative expansion of quartic harmonic oscillator.

</DOC>
<DOC>
<DOCNO> 152000 </DOCNO>
Instantons and Quaternions


  We relate the moduli space of Yang-Mills instantons to quaternionic
manifolds. For instanton number one, the Wolf spaces play an important role. We
apply these ideas to instanton calculations in N=4 SYM theory.

</DOC>
<DOC>
<DOCNO> 120501 </DOCNO>
The quark star in the Quark Mean Field approach


  The quark star in the quark mean field (QMF) extended to include the strange
mesons interaction is examined. The quark star properties in this model are
studied.

</DOC>
<DOC>
<DOCNO> 70283 </DOCNO>
Precise Predictions for Four-Fermion Production in Electron-Positron


  The complete O(alpha) electroweak radiative corrections to e+e- --> WW --> 4f
in the electroweak Standard Model are presented in the double-pole
approximation. We give analytical and numerical results for the
non-factorizable corrections and express the factorizable virtual corrections
in terms of the known corrections to on-shell W-pair production and W decay.
The full matrix elements to the lowest order processes e+e- --> 4f+gamma are
taken into account for the real corrections. The matching of soft and collinear
singularities between virtual and real corrections is done using the
subtraction method. A Monte Carlo generator is constructed which corresponds to
the subtraction branch of RacoonWW. Various numerical results are presented.

</DOC>
<DOC>
<DOCNO> 84966 </DOCNO>
Numerical Analysis of the Wave Function of the Multidimensional Universe


  In the framework of the Hartle-Hawking no-boundary proposal, we investigate
quantum creation of the multidimensional universe with the cosmological
constant $\Lambda$ but without matter fields. In this paper we solved the
Wheeler-de Witt equation numerically. We find that the universe in which both
of the spaces expand exponentially is the most probable in this model.

</DOC>
<DOC>
<DOCNO> 170757 </DOCNO>
Black Hole Evaporation Entails an Objective Passage of Time


  Time's apparent passage has long been debated by philosophers, with no
decisive argument for or against its objective existence. In this paper we show
that introducing the issue of determinism gives the debate a new, empirical
twist. We prove that any theory that states that the basic laws of physics are
time-symmetric must be strictly deterministic. It is only determinism that
enables time reversal, whether theoretical or experimental, of
anyentropy-increasing process. A contradiction therefore arises between
Hawking's argument that physical law is time-symmetric and his controversial
claim that black-hole evaporation introduces a fundamental unpredictability
into the physical world. The latter claim forcibly entails an intrinsic
time-arrow independent of boundary conditions. A simulation of a simple system
under time reversal shows how an intrinsic time arrow re-emerges, destroying
the time reversal, when even the slightest failure of determinism occurs. This
proof is then extended to the classical behavior of black holes. We conclude
with pointing out the affinity between time's arrow and its apparent passage.

</DOC>
<DOC>
<DOCNO> 80594 </DOCNO>
A numerical treatment of Neuberger's lattice Dirac operator


  We describe in some detail our numerical treatment of Neuberger's lattice
Dirac operator as implemented in a practical application. We discuss the
improvements we have found to accelerate the numerical computations and give an
estimate of the expense when using this operator in practice.

</DOC>
<DOC>
<DOCNO> 121906 </DOCNO>
Probing the Substellar Regime with SIRTF


  One of the main scientific drivers of the Space InfraRed Telescope Facility
(SIRTF) is the search for brown dwarfs and extrasolar superplanets. We discuss
observational strategies for identification of these objects, and conclude that
an optimal strategy is a wide IRAC survey (18 deg$^2$) with a 5 $\sigma$
sensitivity of 3.9 $\mu$Jy in channel 2 (M$\sim19.1^m$). For this sensitivity,
we provide estimates of the number of low mass brown dwarfs and isolated
planets detected per square degree for power-law mass functions with
$\alpha$=1.5, and 1.0. Shallower surveys covering a larger area are inefficient
because of large overheads and detector noise. Deeper surveys covering a
smaller area become more and more affected by crowding with galaxies. A survey
like the one that we propose would determine the field mass function down to a
few Jupiter masses through the identification of a large sample of brown dwarfs
and isolated planets. The proposed SIRTF survey would also allow the first
detection of ultracool substellar objects with temperatures between 700 K and
200 K. The cooling curves of substellar objects with masses less than 20
Jupiters imply that they should spend most of their lifetimes at temperatures
below 700 K. Preliminary models indicate that their atmospheres could be
dominated by water clouds, which would diminish their optical and near-infrared
fluxes. The properties of those objects are still completely unexplored.

</DOC>
<DOC>
<DOCNO> 121899 </DOCNO>
Early observations of the Afterglow of GRB000301c


  We report multiband observations of the Optical Transient (OT) associated
with GRB000301c carried out between 2--4 March 2000 using the 2.34-m Vainu
Bappu Telescope (VBT) at Kavalur, India. When combined with other reported
data, the initial decline in the R-band magnitude with log ($t-t_0$), the time
since the burst is fit with a slope $\alpha_{1}$ = -0.70 $\pm$ 0.07 which
steepens after about 6.0 days to a slope of $\alpha_{2}$ = -2.44 $\pm$ 0.29.
This change in slope does not occur smoothly but there is an indication for a
bimodal distribution. The available measurements of the evolution of (B--R)
color do not show any discernible evolution in the first 12 days.

</DOC>
<DOC>
<DOCNO> 69012 </DOCNO>
BCP3: Summary of Theory


  I discuss a number of the highlights in theory presented at the BCP3
conference. These included new, and more stringent, CKM fits; a critical
overview of heavy hadron lifetimes; progress in computing rates and
CP-asymmetries in charmless B-decays; a thorough discussion of the implications
of the new results on $\epsilon^{\prime}/\epsilon$; and, finally, a peek at the
future, trying to estimate how well one is going to be able to measure the
unitarity triangle angles.

</DOC>
<DOC>
<DOCNO> 8835 </DOCNO>
Structures and propagation in globally coupled systems with time delays


  We consider an ensemble of globally coupled phase oscillators whose
interaction is transmitted at finite speed. This introduces time delays, which
make the spatial coordinates relevant in spite of the infinite range of the
interaction. We show that one-dimensional arrays synchronize in an asymptotic
state where all the oscillators have the same frequency, whereas their phases
are distributed in spatial structures that -in the case of periodic boundaries-
can propagate, much as in coupled systems with local interactions.

</DOC>
<DOC>
<DOCNO> 119300 </DOCNO>
A large age for the pulsar B1757-24 from an upper limit on its proper


  The "characteristic age" of a pulsar usually is considered to approximate its
true age, but this assumption has led to some puzzling results, including the
fact that many pulsars with small characteristic ages have no associated
supernova remnants. The pulsar B1757-24 is located just beyond the edge of a
supernova remnant; the properties of the system indicate that the pulsar was
born at the centre of the remnant, but that it has subsequently overtaken the
expanding blast-wave. With a characteristic age of 16,000 yr, this implies an
expected proper motion by the pulsar of 63-80 milliarcsec per year. Here we
report observations of the nebula surrounding the pulsar which limit its proper
motion to less than 25 mas/yr, implying a minimum age of 39,000 yr. A more
detailed analysis argues for a true age as great as 170,000 yr, significantly
larger than the characteristic age. From this result and other discrepancies
associated with pulsars, we conclude that characteristic ages seriously
underestimate the true ages of pulsars.

</DOC>
<DOC>
<DOCNO> 174464 </DOCNO>
Shape of the 8B Alpha and Neutrino Spectra


  The beta-delayed alpha spectrum from the decay of 8B has been measured with a
setup that minimized systematic uncertainties that affected previous
measurements. Consequently the deduced neutrino spectrum presents much smaller
uncertainties than the previous recommendation. The 8B neutrino spectrum is
found to be harder than previously recommended with about (10-20)% more
neutrinos at energies between 12-14 MeV. The efficiencies of the 37Cl, 71Ga,
40Ar, and SuperKamiokande detectors are respectively, 3.6%, 1.4%, 5.7% and 1.8%
larger than previously thought.

</DOC>
<DOC>
<DOCNO> 152335 </DOCNO>
A Note on Compactifications on Spin(7)-Holonomy Manifolds


  In this note we consider compactifications of ${\cal M}$-theory on
$Spin(7)$-holonomy manifolds to three-dimensional Minkowski space. In these
compactifications a warp factor is included. The conditions for unbroken N=1
supersymmetry give rise to determining equations for the 4-form field strength
in terms of the warp factor and the self-dual 4-form of the internal manifold.

</DOC>
<DOC>
<DOCNO> 84606 </DOCNO>
Wormhole with Quantum Throat


  A wormhole with a quantum throat on the basis of an approximate model of the
spacetime foam is presented. An effective spinor field is introduced for the
description of the spacetime foam. The consequences of such model of the
wormhole is preventing a "naked'' singularity in the Reissner-Nordstr\"om
solution with $|e|/m > 1$.

</DOC>
<DOC>
<DOCNO> 69734 </DOCNO>
On the search for 50 GeV neutrinos


  Using the computer code CompHEP we estimate the number of events and the
background, at LEP II and TESLA, for the reaction $e^+ e^- \to N\bar{N}\gamma$,
where $N$ is a hypothetical Dirac neutrino with mass of the order of 50 GeV.

</DOC>
<DOC>
<DOCNO> 120012 </DOCNO>
The profile of an emission line from relativistic outflows around a


  Recent observations show strong evidence for the presence of Doppler-shifted
emission lines in the spectrum of both black hole candidates and active
galactic nuclei. These lines are likely to originate from relativistic outflows
(or jets) in the vicinity of the central black hole. Consequently, the profile
of such a line should be distorted by strong gravitational effects near the
black hole, as well as special relativistic effects. In this paper, we present
results from a detailed study on how each process affects the observed line
profile. We found that the profile is sensitive to the intrinsic properties of
the jets (Lorentz factor, velocity profile, and emissivity law), as well as to
the spin of the black hole and the viewing angle (with respect to the axis of
the jets). More specifically, in the case of approaching jets, an intrisically
narrow line (blue-shifted) is seen as simply broadened at small viewing angles,
but it shows a doubly peaked profile at large viewing angles for extreme Kerr
black holes (due to the combination of gravitational focusing and Doppler
effects); the profile is always singly peaked for Schwarzschild black holes.
For receding jets, however, the line profile becomes quite complicated owing to
complicated photon trajectories. To facilitate comparison with observations, we
searched a large parameter space to derive representative line profiles. We
show the results and discuss how to use emission lines as a potential tool for
probing the inner region of a black hole jet system.

</DOC>
<DOC>
<DOCNO> 7654 </DOCNO>
Cumulant expansion method in the density matrix approach to wave packet


  A non-Markovian master equation for a molecule interacting with a heat bath
is obtained using the cumulant expansion method. The equation is applied to the
problem of molecular wave packet relaxtional dynamics. An exact solution is
derived that demonstrates classical type of squeezing for the wave packet
evolution and a heat-bath dependent frequency shift.

</DOC>
<DOC>
<DOCNO> 101642 </DOCNO>
On the analyticity of CR mappings between nonminimal hypersurfaces


  Let M be a connected real-analytic hypersurface in two dimensional complex
space, $\mathbb C^2$, containing a connected complex hypersurface E, and let f
be a smooth CR mapping sending M into another real-analytic hypersurface M' in
$\mathbb C^2$. In this paper, we prove that if f does not collapse E to a point
and does not collapse M into the image of E, and if the Levi form of M vanishes
to first order along E, then f is real-analytic in a neighborhood of E. In
general, the corresponding statement is false if the Levi form of M vanishes to
second order or higher, in view of an example due to the author. We also show
analogous results in higher dimensions provided that the target M' satisfies a
certain nondegeneracy condition.
  The main ingredient in the proof, which seems to be of independent interest,
is the prolongation of the system defining a CR mapping sending M into M' to a
Pfaffian system on M with singularities along E. The nature of the singularity
is described by the order of vanishing of the Levi form along E.

</DOC>
<DOC>
<DOCNO> 102158 </DOCNO>
Outer Automorphism Groups of Ordered Permutation Groups


  An infinite linearly ordered set (S,<=) is called doubly homogeneous if its
automorphism group A(S) acts 2-transitively on it. We show that any group G
arises as outer automorphism group G cong Out(A(S)) of the automorphism group
A(S), for some doubly homogeneous chain (S,<=).

</DOC>
<DOC>
<DOCNO> 150989 </DOCNO>
Mirror symmetry by O3-planes


  We construct the three dimensional mirror theory of SO(2k) and SO(2k+1) gauge
groups by using O3-planes. An essential ingredient in constructing the mirror
is the splitting of a physical brane (NS-brane or D5-brane) on O3-planes. In
particular, matching the dimensions of moduli spaces of mirror pair (for
example, the SO(2k+1) and its mirror) there is a D3-brane creation or
annihilation accompanying the splitting. This novel dynamical process gives a
nontrivial prediction for strongly coupled field theories, which will be very
interesting to check by Seiberg-Witten curves. Furthermore, applying the same
idea, we revisit the mirror theory of Sp(k) gauge group and find new mirrors
which differ from previously known results. Our new result for Sp(k) gives
another example to a previously observed fact, which shows that different
theories can be mirror to the same theory. We also discussed the phenomena such
as "hidden FI-parameters" when the number of flavors and the rank of the gauge
group satisfy certain relations, ``incomplete Higgsing'' for the mirror of
SO(2k+1) and the ``hidden global symmetry''. After discussing the mirror for a
single Sp or SO gauge group, we extend the study to a product of two gauge
groups in two different models, namely the elliptic and the non-elliptic
models.

</DOC>
<DOC>
<DOCNO> 116602 </DOCNO>
Geometry of River Networks II: Distributions of Component Size and


  The structure of a river network may be seen as a discrete set of nested
sub-networks built out of individual stream segments. These network components
are assigned an integral stream order via a hierarchical and discrete ordering
method. Exponential relationships, known as Horton's laws, between stream order
and ensemble-averaged quantities pertaining to network components are observed.
We extend these observations to incorporate fluctuations and all higher moments
by developing functional relationships between distributions. The relationships
determined are drawn from a combination of theoretical analysis, analysis of
real river networks including the Mississippi, Amazon and Nile, and numerical
simulations on a model of directed, random networks. Underlying distributions
of stream segment lengths are identified as exponential. Combinations of these
distributions form single-humped distributions with exponential tails, the sums
of which are in turn shown to give power law distributions of stream lengths.
Distributions of basin area and stream segment frequency are also addressed.
The calculations identify a single length-scale as a measure of size
fluctuations in network components. This article is the second in a series of
three addressing the geometry of river networks.

</DOC>
<DOC>
<DOCNO> 120904 </DOCNO>
A new sample of giant radio galaxies from the WENSS survey II - A


  We have formed a complete sample of 26 low redshift (z < 0.3) giant radio
galaxies (GRGs) from the WENSS survey, selected at flux densities above 1 Jy at
325 MHz. We present 10.5-GHz observations with the 100-m Effelsberg telescope
of 18 sources in this sample. These observations, together with similar data of
the remaining eight sources, are combined with data from the WENSS, NVSS and
GB6 surveys to study the radio properties of the lobes of these sources at
arcminute resolution. We investigate radio source asymmetries, equipartition
energy densities in the lobes, the presence of lobe pressure evolution with
redshift, the spectral age and the density of the environments of these
sources. We find that the armlength asymmetries of GRGs are slightly larger
than those of smaller sized 3CR radio galaxies and that these are difficult to
explain as arising from orientation effects only. We also find indications that
the lobes of the GRGs, despite their large sizes, are still overpressured with
respect to their environment. Further, we argue that any evolution of lobe
pressure with redshift in these large sources is due to selection effects. A
spectral ageing analysis suggests that the GRGs in our sample are the oldest
members of the group of relatively high power radio sources whose radio powers
have evolved to their currently observed lower values.

</DOC>
<DOC>
<DOCNO> 10953 </DOCNO>
Moving Wigner Glasses and Smectics: Dynamics of Disordered Wigner


  We examine the dynamics of driven classical Wigner solids interacting with
quenched disorder from charged impurities. For strong disorder, the initial
motion is plastic -- in the form of crossing winding channels. For increasing
drive, the disordered Wigner glass can reorder to a moving Wigner smectic --
with the electrons moving in non-crossing 1D channels. These different dynamic
phases can be related to the conduction noise and I(V) curves. For strong
disorder, we show criticality in the voltage onset just above depinning. We
also obtain the dynamic phase diagram for driven Wigner solids and prove that
there is a finite threshold for transverse sliding, recently found
experimentally.

</DOC>
<DOC>
<DOCNO> 116696 </DOCNO>
A new approach to study energy transfer in turbulence


  The unit of nonlinear interaction in Navier-Stokes and the
Magnetohydrodynamic (MHD) equations is a wavenumber triad ({\bf k,p,q})
satisfying ${\bf k+p+q=0}$. The expression for the combined energy transfer
from two of these wavenumbers to the third wavenumber is known. In this paper
we introduce the idea of an effective energy transfer between a pair of modes
through the mediation of the third mode and then find an expression for it. In
fluid turbulence, energy transfer takes place between a pair of velocity modes,
whereas in MHD turbulence energy transfer takes places between (1) a pair of
velocity modes, (2) a pair of magnetic modes, and (3) between a velocity and a
magnetic mode in a triad. In this paper we have obtained the expression for
each of these transfers. We also show how the effective mode-to-mode energy
transfer rate can be utilised to study energy cascades and shell-to-shell
energy transfer rates.

</DOC>
<DOC>
<DOCNO> 150735 </DOCNO>
A New Basis Function Approach to 't Hooft Equation


  We present the new basis functions to investigate the 't Hooft equation, the
lowest order mesonic Light-Front Tamm-Dancoff equation for $\rm SU(N_C)$ gauge
theories. We find the wave function can be well approximated by new basis
functions and obtain an analytic formula for the mass of the lightest bound
state. Its value is consistent with the precedent results.

</DOC>
<DOC>
<DOCNO> 170405 </DOCNO>
Uncertainty for spin systems


  A modified definition of quantum mechanical uncertainty D for spin systems,
which is invariant under the action of SU(2), is suggested. Its range is shown
to be h^2j<D<h^2j(j+1) within any irreducible representation j of SU(2) and its
mean value in Hilbert space computed using the Fubini-Study metric is
determined to be mean(D)=h^2j(j+1/2). The most used sets of coherent states in
spin systems coincide with the set of minimum D uncertainty states.

</DOC>
<DOC>
<DOCNO> 8915 </DOCNO>
Observation of a linear temperature dependence of the critical current


  For a Ba_{0.63}K_{0.37}BiO_3 single crystal with T_c=31 K, H_{c1}=750 Oe at 5
K, and dimensions 3x3x1 mm^3, the temperature and field dependences of magnetic
hysteresis loops have been measured within 5-25 K in magnetic fields up to 6
Tesla. The critical current density is J_c(0)=1.5 x 10^5 A/cm^2 at zero field
and 1 x 10^5 A/cm^2 at 1 kOe at 5 K. J_c decreases exponentially with
increasing field up to 10 kOe. A linear temperature dependence of J_c is
observed below 25 K, which differs from the exponential and the power-law
temperature dependences in high-Tc superconductors including the BKBO. The
linear temperature dependence can be regarded as an intrinsic effect in
superconductors.

</DOC>
<DOC>
<DOCNO> 85089 </DOCNO>
Interacting Black Holes


  We revisit the geometry representing l collinear Schwarzschild black holes.
It is seen that the black holes' horizons are deformed by their mutual
gravitational attraction. The geometry has a string like conical singularity
that connects the holes but has nevertheless a well defined action. Using
standard gravitational thermodynamics techniques we determine the Free energy
for two black holes at fixed temperature and distance, their entropy and mutual
force. When the black holes are far apart the results agree with Newtonian
gravity expectations. This analyses is generalized to the case of charged black
holes. Then we consider black holes embedded in String/M-theory as bound states
of branes. Using the effective string description of these bound states and for
large separation we reproduce exactly the semi-classical result for the
entropy, including the correction associated with the interaction between the
holes.

</DOC>
<DOC>
<DOCNO> 70984 </DOCNO>
Quark-Hadron Duality


  I review the notion of the quark-hadron duality from the modern perspective.
Both, the theoretical foundation and practical applications are discussed. The
proper theoretical framework in which the problem can be formulated and treated
is Wilson's operator product expansion (OPE). Two models developed for the
description of duality violations are considered in some detail: one is
instanton-based, another resonance-based. The mechanisms they represent are
complementary. Although both models are rather primitive (their largest virtue
is their simplicity) they hopefully capture important features of the
phenomenon. Being open for improvements, they can be used "as is" for
orientation in the studies of duality violations in the processes of practical
interest.

</DOC>
<DOC>
<DOCNO> 100358 </DOCNO>
Moment Inequalities for Symmetric Statistics


  In this paper, we prove analogues of Khintchine and Rosenthal's moment
inequalities for symmetric statistics (U-statistics) of arbitrary order. An
example that shows significance of each term in the analogues of Rosenthal's
bounds for symmetric statistics is constructed as well.

</DOC>
<DOC>
<DOCNO> 85399 </DOCNO>
Gravitational Charges: a covariant phase space analysis in even


  The gravitational Noether charges are studied in the context of the first
order gravitational theories for asymptotically locally anti de Sitter spaces.
The thermodynamical properties of these first order gravitational theories are
also analyzed.

</DOC>
<DOC>
<DOCNO> 68985 </DOCNO>
A Brane-World Explanation of the KARMEN Anomaly


  Motivated by the anomaly in the KARMEN experiment, we study new possibilities
for brane-world models of neutrino masses. We show that the KARMEN anomaly can
be understood in the context of a six-dimensional brane-world model. The
fine-tuning problem associated with the single-particle interpretation of the
anomaly is thereby alleviated. Our model shows some interesting properties of
general interest for brane-world neutrino physics. In particular, the size of
the brane-bulk mixing decouples from the scales relevant for atmospheric and
solar neutrino oscillations.

</DOC>
<DOC>
<DOCNO> 71750 </DOCNO>
Generating Neutrino Mass in the 331 Model


  A mechanism for generating small tree-level Majorana mass for neutrinos is
implemented in the 331 Model. No additional fermions or scalars need to be
added, and no mass scale greater than a few TeV is invoked.

</DOC>
<DOC>
<DOCNO> 84416 </DOCNO>
An analysis of cosmological perturbations in hydrodynamical and field


  Density fluctuations of fluids with negative pressure exhibit decreasing time
behaviour in the long wavelength limit, but are strongly unstable in the small
wavelength limit when a hydrodynamical approach is used. On the other hand, the
corresponding gravitational waves are well behaved. We verify that the
instabilities present in density fluctuations are due essentially to the
hydrodynamical representation; if we turn to a field representation that lead
to the same background behaviour, the instabilities are no more present. In the
long wavelength limit, both approachs give the same results. We show also that
this inequivalence between background and perturbative level is a feature of
negative pressure fluid. When the fluid has positive pressure, the
hydrodynamical representation leads to the same behaviour as the field
representation both at the background and perturbative levels.

</DOC>
<DOC>
<DOCNO> 80830 </DOCNO>
Towards the application of the Maximum Entropy Method to finite


  According to the Narnhofer Thirring Theorem interacting systems at finite
temperature cannot be described by particles with a sharp dispersion law. It is
therefore mandatory to develop new methods to extract particle masses at finite
temperature. The Maximum Entropy method offers a path to obtain the spectral
function of a particle correlation function directly. We have implemented the
method and tested it with zero temperature Upsilon correlation functions
obtained from an NRQCD simulation. Results for different smearing functions are
discussed.

</DOC>
<DOC>
<DOCNO> 170483 </DOCNO>
Self-Binding Transition in Bose Condensates with Laser-Induced


  In our recent publication (D. O'Dell, et al, Phys. Rev. Lett. 84, 5687
(2000)) we proposed a scheme for electromagnetically generating a self-bound
Bose-Einstein condensate with 1/r attractive interactions: the analog of a Bose
star. Here we focus upon the conditions neccessary to observe the transition
from external trapping to self-binding. This transition becomes manifest in a
sharp reduction of the condensate radius and its dependence on the laser
intensity rather that the trap potential.

</DOC>
<DOC>
<DOCNO> 68808 </DOCNO>
APACIC++, A PArton Cascade In C++, version 1.0


  APACIC++ is a Monte-Carlo event-generator dedicated for the simulation of
electron-positron annihilations into jets. Within the framework of APACIC++,
the emergence of jets is identified with the perturbative production of partons
as governed by corresponding matrix elements. In addition to the build-in
matrix elements describing the production of two and three jets, further
programs can be linked allowing for the simultaneous treatment of higher
numbers of jets. APACIC++ hosts a new approach for the combination of arbitrary
matrix elements for the production of jets with the parton shower, which in
turn models the evolution of these jets. For the evolution, different ordering
schemes are available, namely ordering by virtualities or by angles. At the
present state, the subsequent hadronization of the partons is accomplished by
means of the Lund-string model as provided within Pythia. An appropriate
interface is provieded.
  The program takes full advantage of the object-oriented features provided by
C++ allowing for an equally abstract and transparent programming style.

</DOC>
<DOC>
<DOCNO> 178905 </DOCNO>
Phase transitions in high energy heavy ion collisions within fluid


  Recent advances in Fluid Dynamical modeling of heavy ion collisions are
presented, with particular attention to mesoscopic systems, QGP formation in
the pre FD regime and QGP hadronization coinciding with the final freeze-out.

</DOC>
<DOC>
<DOCNO> 120813 </DOCNO>
On the magnetism of stars and planets


  A self-consistent statistical approach to the problem of planetary and
stellar magnetism is suggested. The mechanism of magnetic field generation in
the astronomical objects, where the existence of fields is associated with the
axial rotation of objects, is discussed. In the general case different forces
produce partial R-separation of the charges. As a result of the system
rotation, the magnetic fields of the currents of these charges are not
compensated. The influence of various factors on the magnetic field of some
object is analysed.

</DOC>
<DOC>
<DOCNO> 122632 </DOCNO>
XMM-Newton EPIC Observation of SMC SNR 0102-72.3


  Results from observations of the young oxygen-rich supernova remnant SNR
0102-72.3 in the Small Magellanic Cloud during the calibration phase of the
XMM-Newton Observatory are presented. Both EPIC-PN and MOS observations show a
ringlike structure with a radius of ~15'' already known from Einstein, ROSAT
and Chandra observations. Spectra of the entire SNR as well as parts in the
eastern half were analyzed confirming shocked hot plasma in non-uniform
ionization stages as the origin of the X-ray emission. The spectra differ in
the northeastern and the southeastern part of the X-ray ring, showing emission
line features of different strength. The temperature in the northeastern part
is significantly higher than in the southeast, reflected by the lines of higher
ionization stages and the harder continuum. Comparison to radio data shows the
forward shock of the blast wave dominating in the northern part of the SNR,
while the southern emission is most likely produced by the recently formed
reverse shock in the ejecta. In the case of the overall spectrum of SNR
0102-72.3, the two-temperature non-equilibrium ionization model is more
consistent with the data in comparison to the single plane-parallel shock
model. The structure of SNR 0102-72.3 is complex due to variations in shock
propagation leading to spatially differing X-ray spectra.

</DOC>
<DOC>
<DOCNO> 119845 </DOCNO>
Rejection of the hypothesis that Markarian 501 TeV photons are pure


  The energy spectrum of the Blazar type galaxy Markarian 501 (Mrk 501) as
measured by the High-Energy-Gamma-Ray Astronomy (HEGRA) air Cerenkov telescopes
extends beyond 16 TeV and constitutes the most energetic photons observed from
an extragalactic object. A fraction of the emitted spectrum is possibly
absorbed in interactions with low energy photons of the diffuse extragalactic
infrared radiation, which in turn offers the unique possibility to measure the
diffuse infrared radiation density by TeV spectroscopy. The upper limit on the
density of the extragalactic infrared radiation derived from the TeV
observations imposes constraints on models of galaxy formation and stellar
evolution. One of the recently published ideas to overcome severe absorption of
TeV photons is based upon the assumption that sources like Mrk 501 could
produce Bose-Einstein condensates of coherent photons. The condensates would
have a higher survival probability during the transport in the diffuse
radiation field and could mimic TeV air shower events. The powerful
stereoscopic technique of the HEGRA air Cerenkov telescopes allows to test this
hypothesis by reconstructing the penetration depths of TeV air shower events:
Air showers initiated by Bose-Einstein condensates are expected to reach the
maximum of the shower development in the atmosphere earlier than single photon
events. By comparing the energy-dependent penetration depths of TeV photons
from Mrk 501 with those from the TeV standard-candle Crab Nebula and simulated
air shower events, we can reject the hypothesis that TeV photons from Mrk 501
are pure Bose-Einstein condensates.

</DOC>
<DOC>
<DOCNO> 101495 </DOCNO>
Lomonosov's Invariant Subspace Theorem for Multivalued Linear Operators


  The famous Lomonosov's invariant subspace theorem states that if a continuous
linear operator T on an infinite-dimensional normed space E "commutes" with a
compact nonzero operator K, i.e., TK=KT, then T has a non-trivial closed
invariant subspace. We generalize this theorem for multivalued linear
operators.

</DOC>
<DOC>
<DOCNO> 11791 </DOCNO>
Superexchange in the quarter- filled two- leg ladder system NaV2O5


  A theory of superexchange in the mixed valent layer compound NaV2O5 is
presented which provides a consistent description of exchange both in the
disordered and charge ordered state. Starting from results of band structure
calculations for NaV2O5 first an underlying electronic model for a ladder unit
in the Trellis lattice is formulated. By using the molecular orbital
representation for intra-rung electronic states a second-order perturbation
procedure is developed and an effective spin-chain model for a ladder is
derived. Variation of the resulting superexchange integral J is examined
numerically as the ladder system evolves from a charge disordered to the
extreme ('zig-zag') charge ordered state. It is found that the effective intra-
ladder superexchange is always antiferromagnetic.

</DOC>
<DOC>
<DOCNO> 83329 </DOCNO>
Managing Periodically Updated Data in Relational Databases: A Stochastic


  Recent trends in information management involve the periodic transcription of
data onto secondary devices in a networked environment, and the proper
scheduling of these transcriptions is critical for efficient data management.
To assist in the scheduling process, we are interested in modeling the
reduction of consistency over time between a relation and its replica, termed
obsolescence of data. The modeling is based on techniques from the field of
stochastic processes, and provides several stochastic models for content
evolution in the base relations of a database, taking referential integrity
constraints into account. These models are general enough to accommodate most
of the common scenarios in databases, including batch insertions and life spans
both with and without memory. As an initial "proof of concept" of the
applicability of our approach, we validate the insertion portion of our model
framework via experiments with real data feeds. We also discuss a set of
transcription protocols which make use of the proposed stochastic model.

</DOC>
<DOC>
<DOCNO> 99316 </DOCNO>
A formula for Euler characteristic of line singularities on singular


  We prove an algebraic formula for the Euler characteristic of the Milnor
fibres of functions with critical locus a smooth curve on a space which is a
weighted homogeneous complete intersection with isolated singularity.

</DOC>
<DOC>
<DOCNO> 119954 </DOCNO>
GRB 991216 Joins the Jet Set: Discovery and Monitoring of its Optical


  The optical light curve of the energetic gamma-ray burst GRB 991216 is
consistent with jet-like behavior in which a power-law decay steepens from
t**(-1.22 +/- 0.04) at early times to t**(-1.53 +/- 0.05) in a gradual
transition at around 2 d. The derivation of the late-time decay slope takes
into account the constant contribution of a host or intervening galaxy which
was measured 110 d after the event at R = 24.56 +/- 0.14, although the light
curve deviates from a single power law whether or not a constant term is
included. The early-time spectral energy distribution of the afterglow can be
described as F_nu ~ nu**(-0.74 +/- 0.05) or flatter between optical and X-ray,
which, together with the slow initial decay, is characteristic of standard
adiabatic evolution in a uniformly dense medium. Assuming that a reported
absorption-line redshift of 1.02 is correct, the apparent isotropic energy of
6.7 x 10**53 erg is reduced by a factor of ~ 200 in the jet model, and the
initial half-opening angle is ~ 6 deg. GRB 991216 is the third good example of
a jet-like afterglow (following GRB 990123 and GRB 990510), supporting a trend
in which the apparently most energetic gamma-ray events have the narrowest
collimation and a uniform ISM environment. This, plus the absence of evidence
for supernovae associated with jet-like afterglows, suggests that these events
may originate from a progenitor in which angular momentum plays an important
role but a massive stellar envelope or wind does not, e.g., the coalescence of
a compact binary.

</DOC>
<DOC>
<DOCNO> 152026 </DOCNO>
String Loop Corrections to Stable Non-BPS Branes


  We calculate the string loop corrections to the tachyon potential for stable
non-BPS Dp-branes on the orbifold T^4/Z_2. We find a non-trivial phase
structure and we show that, after tachyon condensation, the non-BPS Dp-branes
are attracted to each other for p=0,1,2. We then identify the corresponding
closed string boundary states together with the massless long range fields they
excite. For p=3,4 the string loop correction diverge. We identify the massless
closed string fields responsible for these divergencies and regularise the
partition function using a Fischler-Susskind mechanism.

</DOC>
<DOC>
<DOCNO> 100416 </DOCNO>
Hierarchical structures in Sturmian dynamical systems


  Paper withdrawn; will be replaced by revised version containing application
to lattice models as well.
  We study hierarchical properties of Sturmian words. These properties are
similar to those of substitution dynamical systems. This approach allows one to
carry over to Sturmian dynamical systems methods developed in the context of
substitutions. For example, it allows for a very simple proof of a uniform
ergodic type theorem for additive functions taking values in a Banach space. We
then focus on establishing various versions of uniform subadditive ergodic type
theorems. The main result states that linear repetitivity of a Sturmian system
is equivalent to the validity of a uniform subadditive ergodic theorem which in
turn is equivalent to uniform positivity of certain weights. Thus, the results
of this paper completely cover the validity of uniform additive and subadditive
ergodic theorems on Sturmian systems.

</DOC>
<DOC>
<DOCNO> 40397 </DOCNO>
Virtual Compton Scattering off the Pseudoscalar Meson Octet


  We present a calculation of the virtual Compton scattering amplitude for the
pseudoscalar meson octet in the framework of chiral perturbation theory at
${\cal O}(p^4)$. We calculate the electromagnetic generalized polarizabilities
and compare the results in the real Compton scattering limit to available
experimental values. Finally, we give predictions for the differential cross
section of electron-meson bremsstrahlung.

</DOC>
<DOC>
<DOCNO> 84432 </DOCNO>
Gravitational Energy-Momentum Density in Teleparallel Gravity


  In the context of a gauge theory for the translation group, a conserved
energy-momentum gauge current for the gravitational field is obtained. It is a
true spacetime and gauge tensor, and transforms covariantly under global
Lorentz transformations. By rewriting the gauge gravitational field equation in
a purely spacetime form, it becomes the teleparallel equivalent of Einstein's
equation, and the gauge current reduces to the M{\o}ller's canonical
energy-momentum density of the gravitational field.

</DOC>
<DOC>
<DOCNO> 68622 </DOCNO>
On Thermalization in Classical Scalar Field Theory


  Thermalization of classical fields is investigated in a \phi^4 scalar field
theory in 1+1 dimensions, discretized on a lattice. We numerically integrate
the classical equations of motion using initial conditions sampled from various
nonequilibrium probability distributions. Time-dependent expectation values of
observables constructed from the canonical momentum are compared with thermal
ones. It is found that a closed system, evolving from one initial condition,
thermalizes to high precision in the thermodynamic limit, in a time-averaged
sense. For ensembles consisting of many members with the same energy, we find
that expectation values become stationary - and equal to the thermal values -
in the limit of infinitely many members. Initial ensembles with a nonzero
(noncanonical) spread in the energy density or other conserved quantities
evolve to noncanonical stationary ensembles. In the case of a narrow spread,
asymptotic values of primary observables are only mildly affected. In contrast,
fluctuations and connected correlation functions will differ substantially from
the canonical values. This raises doubts on the use of a straightforward
expansion in terms of 1PI-vertex functions to study thermalization.

</DOC>
<DOC>
<DOCNO> 102532 </DOCNO>
On the Lattes maps of P^k


  Let f be a polynomial endomorphism of degree d>1 of C^k (k>1) which extends
to a holomorphic endomorphism of P^k. Assume that the maximal order Julia set
of f is laminated by real hypersurfaces in some open set. We show that f is
homogenous and is a polynomial lift of a Lattes endomorphism of P^{k-1}.

</DOC>
<DOC>
<DOCNO> 178944 </DOCNO>
On the Structure of Low Lying 0^{+} Excited States of Pt isotopes


  The description of the of nuclei energy spectra of 0^{+} states has been done
involving the degree of their collectivity as a systematics parameter. Within
the framework of this approach the parameter of the collectivity is mainly
determined by pairs of particles placed on single ''effective'' level and
coupled to monopole bosons. Holshtein-Primakoff transformation of these
monopole bosons leads to clear physical explanation of the structure of 0^{+}
states in terms of ''ideal bosons''. The results may be helpful both for
experimentalists and theorists in their investigations of low- lying states
structure and transition probabilities.

</DOC>
<DOC>
<DOCNO> 70586 </DOCNO>
Primordial Galactic Magnetic Fields from the QCD Phase Transition


  In this paper, we propose a mechanism to generate large-scale magnetic fields
with correlations lengths of 100 kpc. Domain walls with QCD scale internal
structure form and coalesce obtaining Hubble size correlations and align
nucleon spins. Due to strong CP violation, nucleons in these walls have
anomalous electric and magnetic dipole moments and thus the walls are
ferromagnetic. This induces electromagnetic fields with Hubble size
correlations. The same CP violation also induces maximal helicity
(Chern-Simons) correlated through the Hubble volume which supports an "inverse
cascade" allowing the initial correlations to grow to 100 kpc today. We
estimate the generated electromagnetic fields in terms of the QCD parameters
and discuss the effects of the resulting fields.

</DOC>
<DOC>
<DOCNO> 174605 </DOCNO>
7-Li(p,n) Nuclear Data Library for Incident Proton Energies to 150 MeV


  We describe evaluation methods that make use of experimental data, and
nuclear model calculations, to develop an ENDF-formatted data library for the
reaction p + Li7 for incident protons with energies up to 150 MeV. The
important 7-Li(p,n_0) and 7-Li(p,n_1) reactions are evaluated from the
experimental data, with their angular distributions represented using Lengendre
polynomial expansions. The decay of the remaining reaction flux is estimated
from GNASH nuclear model calculations. The evaluated ENDF-data are described in
detail, and illustrated in numerous figures. We also illustrate the use of
these data in a representative application by a radiation transport simulation
with the code MCNPX.

</DOC>
<DOC>
<DOCNO> 122888 </DOCNO>
Relativistic corrections to fractal analyses of the galaxy distribution


  The effect of curvature on the results of fractal analyses of the galaxy
distribution is investigated. We show that, if the universe satisfies the
criteria of a wide class of parabolic homogeneous models, the observers
measuring the fractal index with the integrated conditional density procedure
may use the Hubble formula, without having to allow for curvature, out to
distances of 600 Mpc, and possibly far beyond. This contradicts a previous
claim by Ribeiro (1995) that, in the Einstein-de Sitter case, relativistic
corrections should be taken into account at much smaller scales. We state for
the class of cosmological models under study, and give grounds for conjecture
for others, that the averaging procedure has a smoothing effect and that,
therefore, the redshift-distance relation provides an upper limit to the
relativistic corrections involved in such analyses.

</DOC>
<DOC>
<DOCNO> 72027 </DOCNO>
Leading Isgur-Wise form factor of $\Lambda_b\to\Lambda_{c1}$ transition


  The leading Isgur-Wise form factor $\xi(y)$ parametrizing the semileptonic
transitions $\Lambda_b\to\Lambda^{1/2}_{c1}\ell\bar\nu$ and
$\Lambda_b\to\Lambda^{3/2}_{c1}\ell\bar\nu$ is calculated by using the QCD sum
rules in the framework of heavy quark effective theory, where
$\Lambda^{1/2}_{c1}$ and $\Lambda^{3/2}_{c1}$ is the orbitally excited charmed
baryon doublet with $J^P=(1^-/2,3^-/2)$. The interpolating currents with
transverse covariant derivative are adopted for $\Lambda^{1/2}_{c1}$ and
$\Lambda^{3/2}_{c1}$ in the analysis. The slope parameter $\rho^2$ in linear
approximation of the Isgur-Wise function is obtained to be $\rho^2=2.01$, and
the interception to be $\xi(1)=0.29$. The decay branching ratios are estimated.

</DOC>
<DOC>
<DOCNO> 70600 </DOCNO>
New Regime for Dense String Networks


  We uncover a new transient regime that reconciles the apparent inconsistency
of the Martins Shellard one scale damped string evolution model with the
initial conditions predicted by the Kibble mechanism for string formation in a
second order phase transition. This regime carries (in a short cosmic time
$\sim .1 t_c$) the dense string network created by the Kibble {\it{mechanism}}
to the (dilute) Kibble {\it{regime}} in which friction dominated strings remain
till times $t_* \sim (M_P/T_c)^2 t_c$. This is possible beacause the cosmic
time at the phase transition ($t_c$) is much larger than the damping time scale
$l_f\sim T_c^2/T^3$. Our result has drastic implications for various non-GUT
scale string mediated mechanisms.}

</DOC>
<DOC>
<DOCNO> 170387 </DOCNO>
Hadamard Products of Product Operators and the Design of


  An extension of the product operator formalism of NMR is introduced, which
uses the Hadamard matrix product to describe many simple spin 1/2 relaxation
processes. The utility of this formalism is illustrated by deriving NMR
gradient-diffusion experiments to simulate several decoherence models of
interest in quantum information processing, along with their Lindblad and Kraus
representations. Gradient-diffusion experiments are also described for several
more complex forms of decoherence, including the well-known collective
isotropic model. Finally, it is shown that the Hadamard formalism gives a
concise representation of decoherence with arbitrary correlations among the
fluctuating fields at the different spins involved, and that this can be
applied to both decoherence (T2) as well as nonadiabatic relaxation (T1)
processes.

</DOC>
<DOC>
<DOCNO> 83199 </DOCNO>
Perfect simulation from the Quicksort limit distribution


  The weak limit of the normalized number of comparisons needed by the
Quicksort algorithm to sort n randomly permuted items is known to be determined
implicitly by a distributional fixed-point equation. We give an algorithm for
perfect random variate generation from this distribution.

</DOC>
<DOC>
<DOCNO> 170665 </DOCNO>
Quantum interferometric optical lithography:towards arbitrary


  As demonstrated by Boto et al. [Phys. Rev. Lett. 85, 2733 (2000)], quantum
lithography offers an increase in resolution below the diffraction limit. Here,
we generalize this procedure in order to create patterns in one and two
dimensions. This renders quantum lithography a potentially useful tool in
nanotechnology.

</DOC>
<DOC>
<DOCNO> 70981 </DOCNO>
Diquarks in cold dense QCD with two flavors


  We derive and analyze the Bethe-Salpeter equations for spin zero diquarks in
the color superconducting phase of cold dense QCD with two massless flavors.
The spectrum of diquarks contains an infinite number of massive excitations and
five (nearly) massless pseudoscalars. The former are singlets while the latter
include a doublet, an antidoublet and a singlet with respect to the unbroken
$SU(2)_{c}$. Because of an approximate parity doubling at large chemical
potential, all massive states come in pairs. The decay constants, as well as
the velocities of the (nearly) massless pseudoscalars are derived. The
different role of the Meissner effect for tightly bound states and
quasiclassical bound states is revealed.

</DOC>
<DOC>
<DOCNO> 123134 </DOCNO>
Fast Algorithms and Efficient Statistics: N-point Correlation Functions


  We present here a new algorithm for the fast computation of N-point
correlation functions in large astronomical data sets. The algorithm is based
on kdtrees which are decorated with cached sufficient statistics thus allowing
for orders of magnitude speed-ups over the naive non-tree-based implementation
of correlation functions. We further discuss the use of controlled
approximations within the computation which allows for further acceleration. In
summary, our algorithm now makes it possible to compute exact, all-pairs,
measurements of the 2, 3 and 4-point correlation functions for cosmological
data sets like the Sloan Digital Sky Survey (SDSS; York et al. 2000) and the
next generation of Cosmic Microwave Background experiments (see Szapudi et al.
2000).

</DOC>
<DOC>
<DOCNO> 9485 </DOCNO>
The information bottleneck method


  We define the relevant information in a signal $x\in X$ as being the
information that this signal provides about another signal $y\in \Y$. Examples
include the information that face images provide about the names of the people
portrayed, or the information that speech sounds provide about the words
spoken. Understanding the signal $x$ requires more than just predicting $y$, it
also requires specifying which features of $\X$ play a role in the prediction.
We formalize this problem as that of finding a short code for $\X$ that
preserves the maximum information about $\Y$. That is, we squeeze the
information that $\X$ provides about $\Y$ through a `bottleneck' formed by a
limited set of codewords $\tX$. This constrained optimization problem can be
seen as a generalization of rate distortion theory in which the distortion
measure $d(x,\x)$ emerges from the joint statistics of $\X$ and $\Y$. This
approach yields an exact set of self consistent equations for the coding rules
$X \to \tX$ and $\tX \to \Y$. Solutions to these equations can be found by a
convergent re-estimation method that generalizes the Blahut-Arimoto algorithm.
Our variational principle provides a surprisingly rich framework for discussing
a variety of problems in signal processing and learning, as will be described
in detail elsewhere.

</DOC>
<DOC>
<DOCNO> 150921 </DOCNO>
Radiation Pressure as a Source of Decoherence


  We consider the interaction of an harmonic oscillator with the quantum field
via radiation pressure. We show that a `Schrodinger cat' state decoheres in a
time scale that depends on the degree of `classicality' of the state
components, and which may be much shorter than the relaxation time scale
associated to the dynamical Casimir effect. We also show that decoherence is a
consequence of the entanglement between the quantum states of the oscillator
and field two-photon states. With the help of the fluctuation-dissipation
theorem, we derive a relation between decoherence and damping rates valid for
arbitrary values of the temperature of the field. Coherent states are selected
by the interaction as pointer states.

</DOC>
<DOC>
<DOCNO> 12033 </DOCNO>
Impact Proofs for the Work-Hardening Nature of Low- and High-TC


  The remarkable finding of this work is the linear correlation between the
critical temperature of superconducting (SC) transition, Tc, and the
room-temperature half-width of angular correlation of positron annihila- tion
phonons (ACPAP), Go/2, in the series of powder samples of high-Tc YBCO(123)
ceramic superconductors (SCs) with various deficiency of oxygen content. This
correlation points to the existence of fundamental physical parameter of
materials in all-temperature range,which is the crucial one for their
insulator-metal-superconductor (IMSC) transition. We attribute this
key-parameter to the rapid increase and then the steady (due to the minimal
mechanical relaxation rate) lattice compressive deformation - the sudden and
stable jump in work-hardening of crystals). The traces of this compression may
be observed by different methods over a wide range of te- mperatures and used
for the forecast of the parameters of technological interest for the new SCs.

</DOC>
<DOC>
<DOCNO> 119061 </DOCNO>
Magnetospheric Scattering and Emission in Millisecond Pulsars


  We model the formation of magnetospheric components of millisecond pulsar
light curves, deriving an approximate model for the curved space, `swept-back'
dipole field and following photon emission, propagation, and scattering.
Magnetospheric pulse components are strongly affected by rapid rotation and
Schwarzschild effects.

</DOC>
<DOC>
<DOCNO> 117125 </DOCNO>
Slow light in moving media


  We review the theory of light propagation in moving media with extremely low
group velocity. We intend to clarify the most elementary features of
monochromatic slow light in a moving medium and, whenever possible, to give an
instructive simplified picture.

</DOC>
<DOC>
<DOCNO> 39907 </DOCNO>
Design, construction, and operation of SciFi tracking detector for K2K


  We describe the construction and performance of a scintillating fiber
detector used in the near detector for the K2K (KEK to Kamioka, KEK E362) long
baseline neutrino oscillation experiment. The detector uses 3.7 m long and
0.692 mm diameter scintillating fiber coupled to image-intensifier tubes (IIT),
and a CCD camera readout system. Fiber sheet production and detector
construction began in 1997, and the detector was commissioned in March, 1999.
Results from the first K2K runs confirm good initial performance : position
resolution is estimated to be about 0.8 mm, and track finding efficiency is $98
\pm 2$ % for long tracks (i.e., those which intersect more than 5 fiber
planes). The hit efficiency was estimated to be $92 \pm 2$ % using cosmic-ray
muons, after noise reduction at the offline stage. The possibility of using the
detector for particle identification is also discussed.

</DOC>
<DOC>
<DOCNO> 68859 </DOCNO>
Neutrino Masses and Leptonic CP Violation


  Neutrino oscillations as solutions of the solar neutrino problems and the
atmospheric neutrino deficits may restrict neutrino mass squared differences
and mixing angles in three-neutrino mixing scheme. Currently we have several
solutions depending on the interpretations of the solar neutrino problems.
Combining the neutrino oscillation solutions and a mass matrix ansatz, we
investigated the neutrino mass bounds and found possible leptonic CP-violating
rephasing-invariant quantity $J^{l}_{\tiny CP} \leq 0.012$ for large mixing
angle MSW and just-so vacuum oscillations solutions, and $J^{l}_{\tiny CP} \leq
0.0013$ for small mixing angle MSW solution.

</DOC>
<DOC>
<DOCNO> 100018 </DOCNO>
Self-dual Einstein Hermitian four manifolds


  We provide a local classification of self-dual Einstein Riemannian four
manifolds admitting a positively oriented Hermitian structure and characterize
those which carry a hyperhermitian, non-hyperk\"ahlerian structure compatible
with the negative orientation. We finally show that self-dual Einstein
4-manifolds obtained as quaternionic quotients of the Wolf spaces ${\mathbb
H}P^2$, ${\mathbb H}H^2$, $SU(4)/S(U(2)U(2))$, and $SU(2,2)/S(U(2)U(2))$ are
always Hermitian.

</DOC>
<DOC>
<DOCNO> 100265 </DOCNO>
Quantum invariants of 3-manifolds: integrality, splitting, and


  We consider quantum invariants of 3-manifolds associated with arbitrary
simple Lie algebras. Using the symmetry principle we show how to decompose the
quantum invariant as the product of two invariants, one of them is the
invariant corresponding to the projective group. We then show that the
projective quantum invariant is always an algebraic integer, if the quantum
parameter is a prime root of unity. We also show that the projective quantum
invariant of rational homology 3-spheres has a perturbative expansion a la
Ohtsuki. The presentation of the theory of quantum 3-manifold is
self-contained.

</DOC>
<DOC>
<DOCNO> 71542 </DOCNO>
Helioseismology and screening of nuclear reactions in the Sun


  We show that models for screening of nuclear reactions in the Sun can be
tested by means of helioseismology. As well known, solar models using the weak
screening factors are in agreement with data. We find that the solar model
calculated with the anti screening factors of Tsytovitch is not consistent with
helioseismology, both for the sound speed profile and for the depth of the
convective envelope. Moreover, the difference between the no-screening and weak
screening model is significant in comparison with helioseismic uncertainty. In
other words, the existence of screening can be proved by means of
helioseismology.

</DOC>
<DOC>
<DOCNO> 151905 </DOCNO>
Stability of the Rotating Ellipsoidal D0-brane System


  In this note we prove the complete stability of the classical fluctuation
modes of the rotating ellipsoidal membrane. The analysis is carried out in the
full SU(N) setting, with the conclusion that the fluctuation matrix has only
positive eigenvalues. This proves that the solution will remain close to the
original one for all time, under arbitrary infinitesimal perturbations of the
gauge fields.

</DOC>
<DOC>
<DOCNO> 69709 </DOCNO>
Yukawa Textures in Horava-Witten M-Theory


  Recent advances in 11 dimensional Horava-Witten M-theory based on
non-standard embeddings with torus fibered Calabi-Yau manifolds have allowed
the construction of three generation models with Wilson line breaking to the
Standard Model gauge symmetry. Central to these constructions is the existence
of a set of 5-branes in the bulk. We examine within this framework the general
structure of the matter Yukawa couplings and show that M-theory offers an
alternate possible way of achieving the CKM and quark mass hierarchies without
introducing undue fine tuning or (as in conventional analysis) small parameters
raised to high powers. A phenomenological example is presented in accord with
all CKM and quark mass data requiring mainly that the 5-branes cluster near the
second orbifold plane, and that the instanton charges of the physical orbifold
plane vanish. An explicit example of a three generation model with vanishing
physical plane instanton charges based on a torus fibered Calabi-Yau three fold
with a del Pezzo base $dP_7$ and Wilson line breaking is constructed.

</DOC>
<DOC>
<DOCNO> 71398 </DOCNO>
The Topology of the Universe


  The Hilbert-Einstein equations are insufficient to describe the geometry of
the Universe, as they only constrain a local geometrical property: curvature. A
global knowledge of the geometry of space, if possible, would require
measurement of the topology of the Universe. Since the subject was discussed in
1900 by Schwarzschild, observational attempts to measure global topology have
been rare for most of this century, but have accelerated in the 1990's due to
the rapidly increasing amount of observations of non-negligible fractions of
the observational sphere. A brief review of basic concepts of cosmic topology
and of the rapidly growing gamut of diverse and complementary observational
strategies for measuring the topology of the Universe is provided here.

</DOC>
<DOC>
<DOCNO> 70556 </DOCNO>
From colored glass condensate to gluon plasma: equilibration in high


  The initial distribution of gluons at the very early times after a high
energy heavy ion collision is described by the bulk scale $Q_s$ of gluon
saturation in the nuclear wavefunction. The subsequent evolution of the system
towards kinetic equilibrium is described by a non-linear Landau equation for
the single particle distributions \cite{Mueller1,Mueller2}. In this paper, we
solve this equation numerically for the idealized initial conditions proposed
by Mueller, and study the evolution of the system to equilibrium. We discuss
the sensitivity of our results on the dynamical screening of collinear
divergences. In a particular model of dynamical screening, the convergence to
the hydrodynamic limit is seen to be rapid relative to hydrodynamic time
scales. The equilibration time, the initial temperature, and the chemical
potential are shown to have a strong functional dependence on the initial gluon
saturation scale $Q_s$.

</DOC>
<DOC>
<DOCNO> 116561 </DOCNO>
Parameter Sets for 10 TeV and 100 TeV Muon Colliders, and their Study at


  A focal point for the HEMC'99 workshop was the evaluation of straw-man
parameter sets for the acceleration and collider rings of muon colliders at
center of mass energies of 10 TeV and 100 TeV. These self-consistent parameter
sets are presented and discussed. The methods and assumptions used in their
generation are described and motivations are given for the specific choices of
parameter values. The assessment of the parameter sets during the workshop is
then reviewed and the implications for the feasibility of many-TeV muon
colliders are evaluated. Finally, a preview is given of plans for iterating on
the parameter sets and, more generally, for future feasibility studies on
many-TeV muon colliders.

</DOC>
<DOC>
<DOCNO> 10907 </DOCNO>
Phase Evolution in a Kondo Correlated System


  The coherence and phase evolution of electrons in a mesoscopic system in the
Kondo correlated regime were studied. The Kondo effect, in turn, is one of the
most fundamental many-body effects where a localized spin interacts with
conduction electrons in a conductor. Results were obtained by embedding a
quantum dot (QD) in a double path electronic interferometer and measuring
interference of electron waves. The Phase was found to evolve in a range twice
as large as the theoretically predicted one. Moreover, the phase proved to be
highly sensitive to the onset of Kondo correlation, thus serving as a new
fingerprint of the Kondo effect.

</DOC>
<DOC>
<DOCNO> 12646 </DOCNO>
Thermal Magnetization Reversal in Arrays of Nanoparticles


  The results of large-scale simulations investigating the dynamics of
magnetization reversal in arrays of single-domain nanomagnets after a rapid
reversal of the applied field at nonzero temperature are presented. The
numerical micromagnetic approach uses the Landau-Lifshitz-Gilbert equation
including contributions from thermal fluctuations and long-range dipole-dipole
demagnetizing effects implemented using a fast-multipole expansion. The
individual model nanomagnets are 9 nm x 9 nm x 150 nm iron pillars similar to
those fabricated on a surface with STM-assisted chemical vapor deposition [S.
Wirth, et al., J. Appl. Phys {\bf 85}, 5249 (1999)]. Nanomagnets oriented
perpendicular to the surface and spaced 300 nm apart in linear arrays are
considered. The applied field is always oriented perpendicular to the surface.
When the magnitude of the applied field is less than the coercive value, about
2000 Oe for an individual nanomagnet, magnetization reversal in the nanomagnets
can only occur by thermally activated processes. Even though the interaction
from the dipole moment of neighboring magnets in this geometry is only about 1
Oe, less than 1% of the coercive field, it can have a large impact on the
switching dynamics. What determines the height of the free-energy barrier is
the difference between the coercive and applied fields, and 1 Oe can be a
significant fraction of that. The magnetic orientations of the neighbors are
seen to change the behavior of the nanomagnets in the array significantly.

</DOC>
<DOC>
<DOCNO> 179000 </DOCNO>
Evidence for Three Nucleon Force Effects in p-d Elastic Scattering


  A new measurement of the p-d differential cross section at Ep= 1 MeV has been
performed. These new data and older data sets at energies below the deuteron
breakup are compared to calculations using the two-nucleon Argonne v18 and the
three-nucleon Urbana IX potentials. A quantitative estimate of the capability
of these interactions to describe the data is given in terms of a chi^2
analysis. The chi^2 per datum drastically improves when the three-nucleon
interaction is included in the Hamiltonian.

</DOC>
<DOC>
<DOCNO> 10724 </DOCNO>
First observation of Aharonov-Bohm cages in 2-D normal metal networks


  We report on magnetoresistance transport measurements performed on a
bipartite tiling of rhombus in the GaAs/GaAlAs system. We observe for the first
time large amplitude $h/e$ oscillations in this network as compared to the one
measured in square lattices of similar size. These oscillations are the
signature of a recently predicted localization phenomenon induced by
Aharonov-Bohm interferences in this peculiar network.

</DOC>
<DOC>
<DOCNO> 40107 </DOCNO>
Structure Functions at Low x and Q2 at ZEUS


  Using 3.9 $pb^{-1}$ of data from ep $\ra$ eX interactions recorded using the
ZEUS detector in 1997,the proton structure function, F$_2$, has been measured
in the range 0.015 GeV$^2$ $<$ Q$^2 <$ 0.65 GeV$^2$ and $6 \times 10^{-7} < x <
1 \times 10^{-3}$. The analysis is based on data taken incorporating new
detector components. Compared with the previous analysis, these components
allow improved background suppression and better control of systematic
uncertainties, extending the accessible kinematic region towards lower Q$^2$.

</DOC>
<DOC>
<DOCNO> 101059 </DOCNO>
Hyperelliptic Integrable Systems on K3 and Rational Surfaces


  We show several examples of integrable systems related to special K3 and
rational surfaces (e.g., an elliptic K3 surface, a K3 surface given by a double
covering of the projective plane, a rational elliptic surface, etc.). The
construction, based on Beauvilles's general idea, is considerably simplified by
the fact that all examples are described by hyperelliptic curves and Jacobians.
This also enables to compare these integrable systems with more classical
integrable systems, such as the Neumann system and the periodic Toda chain,
which are also associated with rational surfaces. A delicate difference between
the cases of K3 and of rational surfaces is pointed out therein.

</DOC>
<DOC>
<DOCNO> 121463 </DOCNO>
Properties of galaxy halos in Clusters and Voids


  We use the results of a high resolution N-body simulation to investigate the
role of the environment on the formation and evolution of galaxy-sized halos.
Starting from a set of constrained initial conditions, we have produced a final
configuration hosting a double cluster in one octant and a large void extending
over two octants of the simulation box. We present results for two statistics:
the relationship between 1-D velocity dispersion and mass and the probability
distribution of the spin parameter $P(\lambda)$. The \svm relationship is well
reproduced by the Truncated Isothermal Sphere (TIS) model introduced by Shapiro
et al. (1999), although the slope is different from the original prediction. A
series of \svm relationships for different values of the anisotropy parameter
$\beta$, obtained using the theoretical predictions by Lokas and Mamon (2001)
for NFW density profiles are found to be only marginally consistent with the
data. Using some properties of the equilibrium TIS models, we construct
subsamples of {\em fiducial} equilibrium TIS halos from each of the three
subregions, and we study their properties. For these halos, we do find an
environmental dependence of their properties, in particular of the spin
parameter distribution $P(\lambda)$. We study in more detail the TIS model, and
we find new relationships between the truncation radius and other structural
parameters. No gravitationally bound halo is found having a radius larger than
the critical value for gravithermal instability for TIS halos (\rt $\ge 34.2
r_{0}$, where $r_{0}$ is the core radius of the TIS solution). We do however
find a dependence of this relationship on the environment, like for the
$P(\lambda)$ statistics. These facts hint at a possible r\^{o}le of tidal
fields at determining the statistical properties of halos.

</DOC>
<DOC>
<DOCNO> 169975 </DOCNO>
On the Entangling Power of Quantum Evolutions


  We analyze the entangling capabilities of unitary transformations $U$ acting
on a bipartite $d_1\times d_2$-dimensional quantum system. To this aim we
introduce an entangling power measure $e(U)$ given by the mean linear entropy
produced acting with $U$ on a given distribution of pure product states. This
measure admits a natural interpretation in terms of quantum operations. For a
uniform distribution explicit analytical results are obtained using
group-theoretic arguments. The behaviour of the features of $e(U)$ as the
subsystem dimensions $d_1$ and $d_2$ are varied is studied both analytically
and numerically. The two-qubit case $d_1=d_2=2$ is argued to be peculiar.

</DOC>
<DOC>
<DOCNO> 100249 </DOCNO>
A Combinatorial, Strongly Polynomial-Time Algorithm for Minimizing


  This paper presents the first combinatorial polynomial-time algorithm for
minimizing submodular set functions, answering an open question posed in 1981
by Grotschel, Lovasz, and Schrijver. The algorithm employs a scaling scheme
that uses a flow in the complete directed graph on the underlying set with each
arc capacity equal to the scaled parameter. The resulting algorithm runs in
time bounded by a polynomial in the size of the underlying set and the largest
length of the function value. The paper also presents a strongly
polynomial-time version that runs in time bounded by a polynomial in the size
of the underlying set independent of the function value.

</DOC>
<DOC>
<DOCNO> 117800 </DOCNO>
The Properties of Poor Groups of Galaxies: III. The Galaxy Luminosity


  We obtain R-band photometry for galaxies in six nearby poor groups for which
we have spectroscopic data, including 328 new galaxy velocities. For the five
groups with luminous X-ray halos, the composite group galaxy luminosity
function (GLF) is fit adequately by a Schechter function with Mstar = -21.6 +/-
0.4 + 5log h and alpha = -1.3 +/- 0.1. We also find that (1) the ratio of
dwarfs to giants is significantly larger for the five groups with luminous
X-ray halos than for the one marginally X-ray detected group, (2) the composite
GLF for the luminous X-ray groups is consistent in shape with that for rich
clusters, (3) the composite group GLF rises more steeply at the faint end than
that of the field, (4) the shape difference between the field and composite
group GLF's results mostly from the population of non-emission line galaxies,
whose dwarf-to-giant ratio is larger in the denser group environment than in
the field, and (5) the non-emission line dwarfs are more concentrated about the
group center than the non-emission line giants. This last result indicates that
the dwarfs and giants occupy different orbits (i.e., have not mixed completely)
and suggests that the populations formed at a different times. Our results show
that the shape of the GLF varies with environment and that this variation is
due primarily to an increase in the dwarf-to-giant ratio of quiescent galaxies
in higher density regions, at least up to the densities characteristic of X-ray
luminous poor groups. This behavior suggests that, in some environments, dwarfs
are more biased than giants with respect to dark matter. This trend conflicts
with the prediction of standard biased galaxy formation models. (Abridged)

</DOC>
<DOC>
<DOCNO> 10407 </DOCNO>
Open quantum dots: resonances from perturbed symmetry and bound states


  We discuss the Noeckel model of an open quantum dot, i.e., a straight
hard-wall channel with a potential well. If this potential depends on the
longitudinal variable only, there are embedded eigenvalues which turn into
resonances if the symmetry is violated, either by applying a magnetic field or
by deformation of the well. For a weak symmetry breaking we derive the
perturbative expansion of these resonances. We also deduce a sufficient
condition under which the discrete spectrum of such a system (without any
symmetry) survives the presence of a strong magnetic field. It is satisfied, in
particular, if the dot potential is purely attractive.

</DOC>
<DOC>
<DOCNO> 70724 </DOCNO>
Instantons and Nucleon Magnetism


  We construct improved QCD sum rules for the nucleon magnetic moments by
implementing direct-instanton contributions to the operator product expansion
of the nucleon correlator in a magnetic background field. The instanton
contributions are found to affect only those sum rules which had previously
been considered unstable. The new sum rules show a high degree of stability and
reproduce the experimental values of the nucleon magnetic moments for values of
the magnetic quark condensate susceptibility which are consistent with other
estimates.

</DOC>
<DOC>
<DOCNO> 151329 </DOCNO>
Quasi-local structure of p-form theory


  We show that the Hamiltonian dynamics of the self-interacting, abelian p-form
theory in D=2p+2 dimensional space-time gives rise to the quasi-local
structure. Roughly speaking, it means that the field energy is localized but on
closed 2p-dimensional surfaces (quasi-localized). From the mathematical point
of view this approach is implied by the boundary value problem for the
corresponding field equations. Various boundary problems, e.g. Dirichlet or
Neumann, lead to different Hamiltonian dynamics. Physics seems to prefer
gauge-invariant, positively defined Hamiltonians which turn out to be
quasi-local. Our approach is closely related with the standard two-potential
formulation and enables one to generate e.g. duality transformations in a
perfectly local way (but with respect to a new set of nonlocal variables).
Moreover, the form of the quantization condition displays very similar
structure to that of the symplectic form of the underlying p-form theory
expressed in the quasi-local language.

</DOC>
<DOC>
<DOCNO> 116753 </DOCNO>
A realistic quasi-physical model of the 100 metre dash


  A quasi-physical model (having both physical and mathematical roots) of
sprint performances is presented, accounting for the influence of drag
modification via wind and altitude variations. The race time corrections for
both men and women sprinters are discussed, and theoretical estimates for the
associated drag areas are presented. The corrections are consistent with
constant-wind estimates of previous authors, however those for variable wind
are more accentuated for this model. As a practical example, the nullified
World Record and 1988 Olympic 100 m race of Ben Johnson is studied, and
compared with the present World Record of 9.79 s.

</DOC>
<DOC>
<DOCNO> 178714 </DOCNO>
Coupling of Dipole Mode to gamma-unstable Quadrupole Oscillations


  The coupling of the high-lying dipole mode to the low-lying quadrupole modes
for the case of deformed gamma-unstable nuclei is studied. Results from the
geometrical model are compared to those obtained within the dipole boson model.
Consistent results are obtained in both models. The dipole boson model is
treated within the intrinsic frame, with subsequent projection onto the
laboratory frame. As an application, calculations of photonuclear
cross-sections in gamma-unstable nuclei are presented.

</DOC>
<DOC>
<DOCNO> 102534 </DOCNO>
On Whitehead precovers


  It is proved undecidable in ZFC + GCH whether every Z-module has a^{perp}
{Z}-precover.

</DOC>
<DOC>
<DOCNO> 9211 </DOCNO>
t-U-W Model of a d_{x^2-y^2} Superconductor in the Proximity of an AF


  We examine the competition and relationship between an antiferromagnetic (AF)
Mott insulating state and a d_{x^2-y^2} superconducting (SC) state in two
dimensions using semi-analytical, i. e. diagrammatic calculations of the t-U-W
model. The AF Mott insulator is described by the ground state of the
half-filled Hubbard model on a square lattice with on-site Coulomb repulsion U
and nearest neighbor single-particle hopping t. To this model, an extra term W
is added, which depends upon the square of the single-particle nearest-neighbor
hopping. Staying at half-band filling and a constant value of U, it was
previously shown with Quantum-Monte-Carlo (QMC) simulations that one can
generate a quantum transition as a function of the coupling strength, W,
between an AF Mott insulating state and a d_{x^2-y^2} SC state. Here we
complement these earlier QMC simulations with physically more transparent
diagrammatic calculations. We start with a standard Hartree-Fock (HF)
calculation to capture the "high-energy" physics of the t-U-W model. Then, we
derive and solve the Bethe-Salpeter equation, i. e. we account for fluctuation
effects within the time-dependent HF or generalized RPA scheme. Spin- and
charge-susceptibility as well as the effective interaction vertex are
calculated and systematically compared with QMC data. Finally, the
corresponding BCS gap equation obtained for this effective interaction is
solved.

</DOC>
<DOC>
<DOCNO> 120793 </DOCNO>
Arp 119: A High Speed Galaxy Collision with Episodic Star Formation


  Colliding galaxies are excellent laboratories for studying galactic evolution
and global star formation. Computer simulations of galaxy collisions, in which
at least one galaxy has a significant gaseous component, show the production of
density enhancements and shock waves in the interstellar medium. These
high-density regions coincide with the locations of recent, large-scale star
formation in observations of some real colliding galaxies. Thus, combined
n-body/hydrodynamic computer simulations can be used to explore the history and
conditions of star forming regions in colliding galaxies. The galaxy system Arp
119 (CPG 29) contains a southern member, Arp 119S (Mrk 984), that has an
extremely disturbed appearance, and a northern member, Arp 119N, a gas-poor
elliptical. The morphology of both members can be fit well by a simulation in
which a gas-rich disk galaxy has been impacted by an equal mass elliptical that
had a trajectory approximately perpendicular to the plane of the disk and
passed through the disk slightly off-center. We compare multi-wavelength
observations of the Arp 119 system with a combined n-body/SPH simulation of
colliding galaxies. We find that the progression of recent, large-scale star
formation in this galaxy can be accounted for by a single, outwardly
propagating collision-induced density wave in the gas.

</DOC>
<DOC>
<DOCNO> 13281 </DOCNO>
Magnetic field-dependent interplay between incoherent and Fermi liquid


  We present an electrical transport study of the 2-dimensional (2D) organic
conductor tau-(P-(S,S)-DMEDT-TTF)_2(AuBr)_2(AuBr_2)_y (y = 0.75) at low
temperatures and high magnetic fields. The inter-plane resistivity rho_zz
increases with decreasing temperature, with the exception of a slight anomaly
at 12 K. Under a magnetic field B, both rho_zz and the in-plane resistivity
plane rho_xx show a pronounced negative and hysteretic magnetoresistance with
Shubnikov de Haas (SdH)oscillations being observed in some (high
quality)samples above 15 T. Contrary to the predicted single, star-shaped,
closed orbit Fermi surface from band structure calculations (with an expected
approximate area of 12.5% of A_FBZ), two fundamental frequencies F_l and F_h
are detected in the SdH signal. These orbits correspond to 2.4% and 6.8% of the
area of the first Brillouin zone(A_FBZ), with effective masses F_l = 4.0 +/-
0.5 and F_h = 7.3 +/- 0.1. The angular dependence, in tilted magnetic fields of
F_l and F_h, reveals the 2D character of the FS and Angular dependent
magnetoresistance (AMRO) further suggests a FS which is strictly 2-D where the
inter-plane hopping t_c is virtually absent or incoherent. The Hall constant
R_xy is field independent, and the Hall mobility increases by a factor of 3
under moderate magnetic fields. Our observations suggest a unique physical
situation where a stable 2D Fermi liquid state in the molecular layers are
incoherently coupled along the least conducting direction. The magnetic field
not only reduces the inelastic scattering between the 2D metallic layers, but
it also reveals the incoherent nature of interplane transport in the AMRO
spectrum. The apparent ferromagnetism of the hysteretic magnetoresistance
remains an unsolved problem.

</DOC>
<DOC>
<DOCNO> 151896 </DOCNO>
Novel Domain Wall and Minkowski Vacua of D=9 Maximal SO(2) Gauged


  We show that a generalised reduction of D=10 IIB supergravity leads, in a
certain limit, to a maximally extended SO(2) gauged supergravity in D=9. We
show the scalar potential of this model allows both Minkowski and a new type of
domain wall solution to the Bogomol'nyi equations. We relate these vacua to
type IIB D-branes.

</DOC>
<DOC>
<DOCNO> 12333 </DOCNO>
A Kac-potential treatment of nonintegrable interactions


  We consider d-dimensional systems with nonintegrable, algebraically decaying
pairwise interactions. It is shown that, upon introduction of periodic boundary
conditions and a long-distance cutoff in the interaction range, the bulk
thermodynamics can be obtained rigorously by means of a Kac-potential
treatment, leading to an exact, mean-field-like theory. This explains various
numerical results recently obtained for finite systems in the context of
``nonextensive thermodynamics,'' and in passing exposes a strong regulator
dependence not discussed in these studies. Our findings imply that, contrary to
some claims, Boltzmann-Gibbs statistics are sufficient for a standard
description of this class of nonintegrable interactions.

</DOC>
<DOC>
<DOCNO> 8784 </DOCNO>
Monte Carlo study of the scaling of universal correlation lengths in


  Using an elaborate set of simulational tools and statistically optimized
methods of data analysis we investigate the scaling behavior of the correlation
lengths of three-dimensional classical O($n$) spin models. Considering
three-dimensional slabs $S^1\times S^1\times\mathbb{R}$, the results over a
wide range of $n$ indicate the validity of special scaling relations involving
universal amplitude ratios that are analogous to results of conformal field
theory for two-dimensional systems. A striking mismatch of the $n\to\infty$
extrapolation of these simulations against analytical calculations is traced
back to a breakdown of the identification of this limit with the spherical
model.

</DOC>
<DOC>
<DOCNO> 150326 </DOCNO>
Star-Product and Massless Free Field Dynamics in $AdS_4$


  Generic solution of free equations for massless fields of an arbitrary spin
in $AdS_4$ is built in terms of the star-product algebra with spinor generating
elements. A class of "plane wave" solutions is described explicitly.

</DOC>
<DOC>
<DOCNO> 70470 </DOCNO>
Looking for Novel CP-Violating Effects in B->K^*l^+l^-


  The CP-violating asymmetries in the exclusive decay B->K^*l^+l^- (l=e,mu,tau)
are predicted to be exceedingly small in the standard model (SM), thereby
offering an opportunity to assess various new-physics scenarios. We derive
quantitative predictions for various integrated observables in B->K^*mu^+mu^-
decay in the presence of physics beyond the SM with additional CP phases and an
extended operator basis. In particular, a model-independent analysis of CP
asymmetries that require the presence of unitarity phases, in addition to CP
violation, is performed. We find that in the low dimuon invariant mass region
2m_mu<M_{mu^+mu^-}<M_{J/psi}, the CP asymmetries are highly suppressed by small
dynamical phases, assuming that new physics is unlikely to significantly alter
the Wilson coefficients of the operators governing two-body hadronic B decays.
Taking into account current experimental data on the measured b->s gamma rate
and the upper limit on BR(B^0->K^{*0}mu^+mu^-), CP-violating effects of a few
per cent are estimated, even in the presence of new physics with CP phases of
O(1). By contrast, in the high dimuon invariant mass region
M_{psi'}<M_{mu^+mu^-}<(M_B-M_{K^*}) significant CP-violating effects are
possible. Given a branching ratio of 1.8 x 10^{-6}, the CP asymmetries can be
quite substantial (\sim 20% or more), and thus may serve as a means of
discovering physics transcending the SM.

</DOC>
<DOC>
<DOCNO> 102788 </DOCNO>
Invitation to higher local fields, Part II, section 4: Drinfeld modules


  This work is a survey of relations between Drinfeld modules and higher
dimensional fields of positive characteristic. The main new result stated is
the expression of vanishing orders of certain modular forms through partial
zeta values.

</DOC>
<DOC>
<DOCNO> 14099 </DOCNO>
Is the purely biquadratic spin 1 chain always massive?


  It is shown that the sl(2)q-invariant open antiferromagnetic XXZ spin chain
with a boundary field has a gapless sector in the thermodynamic limit when its
length is odd. Owing to a Temperley-Lieb equivalence of the spectra, the same
conclusion is drawn for the purely biquadratic spin 1 chain with open
boundaries and odd length.

</DOC>
<DOC>
<DOCNO> 12626 </DOCNO>
Laughlin type wave function for two-dimensional anyon fields in a


  The correlation functions of two-dimensional anyon fields in a KMS-state are
studied. For T=0 the $n$-particle wave functions of noncanonical fermions of
level $\alpha$, $\alpha$ odd, are shown to be of Laughlin type of order
$\alpha$. For $T>0$ they are given by a simple finite-temperature
generalization of Laughlin's wave function. This relates the first and second
quantized pictures of the fractional quantum Hall effect.

</DOC>
<DOC>
<DOCNO> 123084 </DOCNO>
Stellar and nuclear-physics constraints on two r-process components in


  Proceedings of "Nuclei in the Cosmos 2000", Aarhus, Danmark

</DOC>
<DOC>
<DOCNO> 178981 </DOCNO>
Size-shrinking of deuterons in very dilute superfluid nuclear matter


  It is shown within the strong-coupling BCS approach that, starting from the
zero-density limit of superfluid nuclear matter, with increasing density
deuterons first shrink before they start expanding.

</DOC>
<DOC>
<DOCNO> 120980 </DOCNO>
What is the behavior of the ISM in the SMC?


  We describe quantitatively the neutral hydrogen (HI) and dust content of the
interstellar medium (ISM) in the Small Magellanic Cloud (SMC), using the
spatial power spectrum. The velocity modification of the HI density power
spectrum is investigated and discussed.

</DOC>
<DOC>
<DOCNO> 117951 </DOCNO>
Dust Emission from High Redshift QSOs


  We present detections of emission at 250 GHz (1.2 mm) from two high redshift
QSOs from the Sloan Digital Sky Survey sample using the bolometer array at the
IRAM 30m telescope. The sources are SDSSp 015048.83+004126.2 at z = 3.7, and
SDSSp J033829.31+002156.3 at z = 5.0, which is the third highest redshift QSO
known, and the highest redshift mm emitting source yet identified. We also
present deep radio continuum imaging of these two sources at 1.4 GHz using the
Very Large Array. The combination of cm and mm observations indicate that the
250 GHz emission is most likely thermal dust emission, with implied dust masses
of 1e8 M_solar. We consider possible dust heating mechanisms, including UV
emission from the active nucleus (AGN), and a massive starburst concurrent with
the AGN, with implied star formation rates > 1e3 M_solar/year.

</DOC>
<DOC>
<DOCNO> 151617 </DOCNO>
Rotations and e, $\nu$ Propagators, Part II


  We continue to derive spacetime quantities and spin 1/2 propagators from
rotations. Rotation-invariant projection operators are found for each element
of a four element basis, i.e. a basis for four component quantities with
specific transformation rules under rotations. With these four projection
operators, we make two spacetime invariant projection operators, i.e. once
space, time, energy, and momentum are identified. The spacetime invariant
operators are propagators for free neutrinos. Except for the substitute basis,
the process is the same as the one that gave electron propagators in Part I.
  PACS number(s): 11.30.-j, 11.30.Cp, and 03.65.Fd

</DOC>
<DOC>
<DOCNO> 70417 </DOCNO>
Tests of QCD: Summary of DIS 2000


  This summary of the working group 2 of DIS 2000 encompasses experimental and
theoretical results of jet physics, open and bound state heavy flavour
production, prompt photon production, next-to-leading order QCD calculations
and beyond, instantons, fragmentation, event shapes, and power corrections,
primarily from deep-inelastic scattering and photoproduction at HERA, but also
from the LEP and Tevatron colliders.

</DOC>
<DOC>
<DOCNO> 150867 </DOCNO>
Confined Maxwell Field and Temperature Inversion Symmetry


  We evaluate the Casimir vacuum energy at finite temperature associated with
the Maxwell field confined by a perfectly conducting rectangular cavity and
show that an extended version of the temperature inversion symmetry is present
in this system.

</DOC>
<DOC>
<DOCNO> 119858 </DOCNO>
RX J0911+05: A Massive Cluster Lens at z=0.769


  We report the detection of a massive high-redshift cluster of galaxies near
the quadruple quasar RX~J0911+05, using the LRIS instrument on the Keck-II
telescope. The cluster is found to have a mean redshift of <z>=0.7689+/-0.002
and a velocity dispersion of sigma=836{+180-200} km/s, based on redshift
measurements for 24 member galaxies. This massive high-redshift cluster is the
origin of the unusually large external shear required by lensing models of the
quadruple quasar system. We predict the expected time delay depending on the
exact contribution of the cluster. A measurement of the time delay and further
deep lensing and X-ray observations will unravel useful properties of this
serendipitously discovered high-redshift cluster, and may put interesting
cosmological constraints on H0.

</DOC>
<DOC>
<DOCNO> 119393 </DOCNO>
Evidence against or for topological defects in the BOOMERanG data ?


  The recently released BOOMERanG data was taken as ``contradicting topological
defect predictions''. We show that such a statement is partly misleading.
Indeed, the presence of a series of acoustic peaks is perfectly compatible with
a non-negligible topological defects contribution. In such a mixed perturbation
model (inflation and topological defects) for the source of primordial
fluctuations, the natural prediction is a slightly lower amplitude for the
Doppler peaks, a feature shared by many other purely inflationary models. Thus,
for the moment, it seems difficult to rule out these models with the current
data.

</DOC>
<DOC>
<DOCNO> 150365 </DOCNO>
Domain Walls and Superpotentials from M Theory on Calabi-Yau Three-Folds


  Compactification of M theory in the presence of G-fluxes yields N=2
five-dimensional gauged supergravity with a potential that lifts all
supersymmetric vacua. We derive the effective superpotential directly from the
Kaluza-Klein reduction of the eleven-dimensional action on a Calabi-Yau
three-fold and compare it with the superpotential obtained by means of
calibrations. We discuss an explicit domain wall solution, which represents
five-branes wrapped over holomorphic cycles. This solution has a ``running
volume'' and we comment on the possibility that quantum corrections provide a
lower bound allowing for an AdS_5 vacuum of the 5-dimensional supergravity.

</DOC>
<DOC>
<DOCNO> 122941 </DOCNO>
A multi-frequency study of the radio galaxy NGC326


  We present preliminary results of a multi-frequency study of the inversion
symmetric radio galaxy NGC326 based on VLA observations at 1.4, 1.6, 4.8, 8.5,
and 14.9 GHz. These data allow us to investigate in detail the morphological,
spectral and polarization properties of this peculiar object at different
levels of spatial resolution.

</DOC>
<DOC>
<DOCNO> 67940 </DOCNO>
Light Meson Spectroscopy: Recent Developments and DAFNE


  In this contribution I discuss recent developments in light meson
spectroscopy, and note specific areas in which DAFNE is an especially
appropriate tool for future experiments. One topic of special relevance is the
spectroscopy of excited vector mesons; quite narrow vector hybrids are
predicted by the flux-tube model, which could be produced by DAFNE when
operating in the $M_{e^+e^-}\approx 1.5-2$ GeV range. A second topic, which
would be appropriate for a later date because it requires a rather higher beam
energy, is the production of C=(+) mesons in $\gamma\gamma$ collisions.

</DOC>
<DOC>
<DOCNO> 12916 </DOCNO>
Ground state spin and Coulomb blockade peak motion in chaotic quantum


  We investigate experimentally and theoretically the behavior of Coulomb
blockade (CB) peaks in a magnetic field that couples principally to the
ground-state spin (rather than the orbital moment) of a chaotic quantum dot. In
the first part, we discuss numerically observed features in the magnetic field
dependence of CB peak and spacings that unambiguously identify changes in spin
S of each ground state for successive numbers of electrons on the dot, N. We
next evaluate the probability that the ground state of the dot has a particular
spin S, as a function of the exchange strength, J, and external magnetic field,
B. In the second part, we describe recent experiments on gate-defined GaAs
quantum dots in which Coulomb peak motion and spacing are measured as a
function of in-plane magnetic field, allowing changes in spin between N and N+1
electron ground states to be inferred.

</DOC>
<DOC>
<DOCNO> 119088 </DOCNO>
Far-ultraviolet Spectroscopy of Venus and Mars at 4 A Resolution with


  Far-ultraviolet spectra of Venus and Mars in the range 820-1840 A at 4 A
resolution were obtained on 13 and 12 March 1995, respectively, by the Hopkins
Ultraviolet Telescope (HUT), which was part of the Astro-2 observatory on the
Space Shuttle Endeavour. Longward of 1250 A, the spectra of both planets are
dominated by emission of the CO Fourth Positive band system and strong OI and
CI multiplets. In addition, CO Hopfield-Birge bands, B - X (0,0) at 1151 A and
C - X (0,0) at 1088 A, are detected for the first time, and there is a weak
indication of the E - X (0,0) band at 1076 A in the spectrum of Venus. The B -
X band is blended with emission from OI 1152. Modeling the relative intensities
of these bands suggests that resonance fluorescence of CO is the dominant
source of the emission, as it is for the Fourth Positive system. Shortward of
Lyman-alpha, other emission features detected include OII 834, OI lambda 989,
HI Lyman-beta, and NI 1134 and 1200. For Venus, the derived disk brightnesses
of the OI, OII, and HI features are about one-half of those reported by Hord et
al. (1991) from Galileo EUV measurements made in February 1990. This result is
consistent with the expected variation from solar maximum to solar minimum. The
ArI 1048, 1066 doublet is detected only in the spectrum of Mars and the derived
mixing ratio of Ar is of the order of 2%, consistent with previous
determinations.

</DOC>
<DOC>
<DOCNO> 71643 </DOCNO>
Proper Construction of the continuum in light-cone QCD sum rules


  A proper way of constructing the continuum contributions in light-cone QCD
sum rules (LCQSR) is rigorously demonstrated. Specifically, we calculate the
continuum corresponding to a typical OPE in LCQSR by properly combining the
double dispersion relation with QCD duality. In the limit of zero external
momentum, we impose that the sum rule be equivalent to the one using the single
dispersion relation. This is found to be equivalent to an obvious constraint
that subtraction terms should not contribute to final sum rule results. The
continuum factor constructed in this way differs from the factor appearing in
conventional LCQSR. We demonstrate that the difference substantially affects
the extraction of hadronic parameters from the correlation function involving
baryon currents.

</DOC>
<DOC>
<DOCNO> 178402 </DOCNO>
Symmetry Breaking by Proton-Neutron Pairing


  The symmetries of the $t=1$ and $t=0$ pair-fields are different. The
consequences for rotational spectra are discussed. For $t=1$, the concept of
spontaneous breaking and subsequent restoration of the isospin symmetry turns
out to be important. It permits us to describe the proton-neutron
pair-correlation within the conventional frame of pairing between like
particles. The experimental data are consistent with the presence of a $t=1$
field at low spin in $N\approx Z$ nuclei. For a substantial $t=0$ field, the
spectra of even-even and odd-odd $N\approx Z$ nuclei become similar. The
possibility of a rotationally induced $ J=1$ pair-field at high spin is
considered.

</DOC>
<DOC>
<DOCNO> 117537 </DOCNO>
Probing the Site for r-Process Nucleosyntheis with Abundances of Barium


  We suggest that if the astrophysical site for r-process nucleosynthesis in
the early Galaxy is confined to a narrow mass range of Type II supernova (SN
II) progenitors, with a lower mass limit of Mms = 20 Msun, a unique feature in
the observed distribution of [Ba/Mg] vs.[Mg/H] for extremely metal-poor stars
can be adequately reproduced. We associate this feature, a bifurcation of the
observed elemental ratios into two branches in the Mg abundance interval -2.7 <
[Mg/H] < -2.3, with two distinct processes. The first branch, which we call the
``y''-branch, is associated with the production of Ba and Mg from individual
massive supernovae. We conclude that SNe II with Mms = 20 Msun are the dominant
source of r-process nucleosynthesis in the early Galaxy. An SN-induced chemical
evolution model with this Mms-dependent Ba yield creates the y-branch,
reflecting the different nucleosynthesis yields of [Ba/Mg] for each SN II with
Mms > 20 Msun. The second branch, which we call the ``i''-branch, is associated
with the elemental abundance ratios of stars which were formed in the dense
shells of the interstellar medium swept up by SNe II with Mms < 20 Msun that do
not synthesize r-process elements, and applies to stars with observed Mg
abundances in the range [Mg/H] < -2.7. The Ba abundances in these stars reflect
those of the interstellar gas at the (later) time of their formation. The
existence of a [Ba/Mg] i-branch strongly suggests that SNe II which are
associated with stars of progenitor mass Mms < 20 Msun are infertile sources
for the production of r-process elements. We predict the existence of this
i-branch for other r-process elements, such as europium (Eu), to the extent
that their production site is in common with Ba.

</DOC>
<DOC>
<DOCNO> 10857 </DOCNO>
Possible composite-fermion liquid as a crossover from Wigner crystal to


  The ground state cohesive energies per electron of the composite fermion (CF)
Fermi sea, the Laughlin state and the charge density wave (CDW) at higher
Landau levels (LLs) are computed. It is shown that whereas for $n\geq 2$ LL,
the CDW state is generally more energetically preferable than those of the CF
liquid and the Laughlin liquid, the $\nu =4+1/6$ CF liquid state unexpectedly
has lower ground state energy than that of the CDW state. We suggest this CF
liquid between the Wigner crystal and the bubble phase may lead to the
crossover from the normal integer quantum Hall liquid to the novel re-entrant
integer quantum Hall state observed in the recent magneto-transport
experiments.

</DOC>
<DOC>
<DOCNO> 71508 </DOCNO>
Signals of R-parity violating supersymmetry in neutrino scattering at


  Neutrino oscillation signals at muon storage rings can be faked by
supersymmetric (SUSY) interactions in an R-parity violating scenario. We
investigate the $\tau$-appearance signals for both long-baseline and near-site
experiments, and conclude that the latter is of great use in distinguishing
between oscillation and SUSY effects. On the other hand, SUSY can cause a
manifold increase in the event rate for wrong-sign muons at a long-baseline
setting, thereby providing us with signatures of new physics.

</DOC>
<DOC>
<DOCNO> 118182 </DOCNO>
The NASA Astrophysics Data System: The Search Engine and its User


  The ADS Abstract and Article Services provide access to the astronomical
literature through the World Wide Web (WWW). The forms based user interface
provides access to sophisticated searching capabilities that allow our users to
find references in the fields of Astronomy, Physics/Geophysics, and
astronomical Instrumentation and Engineering. The returned information includes
links to other on-line information sources, creating an extensive astronomical
digital library. Other interfaces to the ADS databases provide direct access to
the ADS data to allow developers of other data systems to integrate our data
into their system.
  The search engine is a custom-built software system that is specifically
tailored to search astronomical references. It includes an extensive synonym
list that contains discipline specific knowledge about search term
equivalences.
  Search request logs show the usage pattern of the various search system
capabilities. Access logs show the world-wide distribution of ADS users.
  The ADS can be accessed at http://adswww.harvard.edu

</DOC>
<DOC>
<DOCNO> 11655 </DOCNO>
What Are Stories Made Of? - Quantitative Categorical Deconstruction of


  We extend the Microscopic Representation approach to the quantitative study
of religious and folk stories: A story encrypting symbolically the creation is
deconstructed into its simplest conceptual elements and their relationships. We
single out a particular kind of relationship which we call "diagonal (or
transitive) link": given 2 relations between the couples of elements AB and
respectively BC, the "diagonal link" is the (composite) relation AC. We find
that the diagonal links are strongly and systematically correlated with the
events in the story that are considered crucial by the experts. We further
compare the number of diagonal links in the symbolic creation story with a folk
tale, which ostensibly narrates the same overt succession of events (but
without pretensions of encrypting additional meanings). We find that the
density of diagonal links per word in the folk story is lower by a factor of 2.
We speculate that, as in other fields the simple transitive operations acting
on elementary objects are at the core of the emergence and recognition of
macroscopic meaning and novelty in complex systems.

</DOC>
<DOC>
<DOCNO> 99687 </DOCNO>
Difference Equations Compatible with Trigonometric KZ Differential


  The trigonometric KZ equations associated with a Lie algebra $\g$ depend on a
parameter $\lambda\in\h$ where $\h\subset\g$ is the Cartan subalgebra. We
suggest a system of dynamical difference equations with respect to $\lambda$
compatible with the KZ equations. The dynamical equations are constructed in
terms of intertwining operators of $\g$-modules.

</DOC>
<DOC>
<DOCNO> 122764 </DOCNO>
Emissive Mechanism on Spectral Variability of Blazars in High


  The new results of the evolution of the synchrotron peak for Mrk 421 are
mostly likely related to the particle acceleration process. In order to account
for the above results, we present a model of blazar variability during the
flare in which the emission comes from accelerating electrons. A diffusion
advection equation of the electron energy distribution is derived to calculate
the spectrum and light curve of synchrotron radiation. We present that the
observed shifts of the synchrotron peak moving to higher energies during the
flare are caused by shock acceleration. The observed relation between changes
in the fluxes at specified frequency ranges and shifts of the peak position is
fitted to constrain the physical parameters of the dissipation region.

</DOC>
<DOC>
<DOCNO> 170465 </DOCNO>
Implementation of a quantum phase gate by the optical Kerr effect


  We show that the optical Kerr effect can be used to construct a quantum phase
gate. It is well known from quantum nondemolition techniques that, as two
photon field modes pass through a Kerr medium, the phase of each mode will be
shifted, and the size of the phase shift will depend on the number of photons
in both modes. We discuss the Hamiltonian responsible for this effect and show
how this can produce an effective photon-photon interaction which corresponds
to the quantum phase gate operating on two qubits each of which is represented
by the elliptical polarization of one photon field. We discuss decoherence and
losses and suggest some methods for dealing with them.

</DOC>
<DOC>
<DOCNO> 68423 </DOCNO>
Wong's equations and the small x effective action in QCD


  We propose a new form for the small x effective action in QCD. This form of
the effective action is motivated by Wong's equations for classical, colored
particles in non-Abelian background fields. We show that the BFKL equation,
which sums leading logarithms in x, is efficiently reproduced with this form of
the action. We argue that this form of the action may be particularly useful in
computing next-to- leading-order results in QCD at small x.

</DOC>
<DOC>
<DOCNO> 122586 </DOCNO>
Hydrodynamic Models of Line-Driven Accretion Disk Winds II: Adiabatic


  We present here numerical hydrodynamic simulations of line-driven accretion
disk winds in cataclysmic variable systems. We calculate wind mass-loss rate,
terminal velocities, and line profiles for CIV (1550 A) for various viewing
angles. The models are 2.5-dimensional, include an energy balance condition,
and calculate the radiation field as a function of position near an optically
thick accretion disk. The model results show that centrifugal forces produce
collisions of streamlines in the disk wind which in turn generate an enhanced
density region, underlining the necessity of two dimensional calculations where
these forces may be represented. For disk luminosity Ldisk = Lsun, white dwarf
mass Mwd = 0.6 Msun, and white dwarf radii Rwd = 0.01 Rsun, we obtain a wind
mass-loss rate of dMwind/dt = 8.0E-12 Msun/yr, and a terminal velocity of ~3000
km/s. The line profiles we obtain are consistent with observations in their
general form, in particular in the maximum absorption at roughly half the
terminal velocity for the blue-shifted component, in the magnitudes of the wind
velocities implied by the absorption components, in the FWHM of the emission
components, and in the strong dependence in inclination angle.

</DOC>
<DOC>
<DOCNO> 117593 </DOCNO>
Analytical Study of Thermonuclear Reaction Probability Integrals


  An analytic study of the reaction probability integrals corresponding to the
various forms of the slowly varying cross-section factor $S(E)$ is attempted.
Exact expressions for reaction probability integrals are expressed in terms of
the extended gamma functions.

</DOC>
<DOC>
<DOCNO> 170469 </DOCNO>
New method for obtaining complex roots in the semiclassical


  A semiclassical formula for the coherent-state propagator requires the
determination of specific classical paths inhabiting a complex phase-space
through a Hamiltonian flux. Such trajectories are constrained to special
boundary conditions which render their determination difficult by common
methods. In this paper we present a new method based on Runge-Kutta integrator
for a quick, easy and accurate determination of these trajectories. Using
nonlinear one dimensional systems we show that the semiclassical formula is
highly accurate as compared to its exact counterpart . Further we clarify how
the phase of the semiclassical approximation is correctly retrieved under time
evolution.

</DOC>
<DOC>
<DOCNO> 169815 </DOCNO>
Quantum Communication with Correlated Nonclassical States


  Nonclassical correlations between the quadrature-phase amplitudes of two
spatially separated optical beams are exploited to realize a two-channel
quantum communication experiment with a high degree of immunity to
interception. For this scheme, either channel alone can have an arbitrarily
small signal-to-noise ratio (SNR) for transmission of a coherent ``message''.
However, when the transmitted beams are combined properly upon authorized
detection, the encoded message can in principle be recovered with the original
SNR of the source. An experimental demonstration has achieved a 3.2 dB
improvement in SNR over that possible with correlated classical sources.
Extensions of the protocol to improve its security against eavesdropping are
discussed.

</DOC>
<DOC>
<DOCNO> 122237 </DOCNO>
SiO Emission in the Multi-Lobe Outflow associated with IRAS 16293-2422


  We have mapped the thermal emission line of SiO (v = 0; J = 2-1) associated
with the quadrupolar molecular outflow driven by the very cold far-infrared
source IRAS 16293-2422. The SiO emission is significantly enhanced in the
northeastern red lobe and at the position ~50" east of the IRAS source. Strong
SiO emission observed at ~50" east of the IRAS source presents evidence for a
dynamical interaction between a part of the eastern blue lobe and the dense
ambient gas condensation, however, such an interaction is unlikely to be
responsible for producing the quadrupolar morphology. The SiO emission in the
northeastern red lobe shows the spatial and velocity structure similar to those
of the CO outflow, suggesting that the SiO emission comes from the molecular
outflow in the northeastern red lobe itself. The observed velocity structure is
reproduced by a simple spatio-kinematic model of bow shock with a shock
velocity of 19-24 km/s inclined by 30-45 deg from the plane of the sky. This
implies that the northeastern red lobe is independent of the eastern blue lobe
and that the quadrupolar structure is due to two separate bipolar outflows.
  The SiO emission observed in the western red lobe has a broad pedestal shape
with low intensity. Unlike the SiO emission in the northeastern red lobe, the
spatial extent of the SiO emission in the western red lobe is restricted to its
central region. The spatial and velocity structures and the line profiles
suggest that three different types of the SiO emission are observed in this
outflow; the SiO emission arises from the interface between the outflowing gas
and the dense ambient gas clump, the SiO emission coming from the outflow lobe
itself, and the broad SiO emission with low intensity observed at the central
region of the outflow lobe.

</DOC>
<DOC>
<DOCNO> 70324 </DOCNO>
The rare decay b--> s gluon beyond leading logarithms


  We calculate the alpha_s virtual corrections to the decay width for b --> s
gluon in the standard model. Also the corresponding order alpha_s
bremsstrahlung corrections are systematically calculated in this paper. The
combined result is free of infrared and collinear singularities, in accordance
with the KLN theorem. Taking into account the existing next-to-leading
logarithmic (NLL) result for the Wilson coefficient C_8^(eff), a complete NLL
result for the branching ratio B(b -> s gluon) is derived. Numerically, we
obtain B^(NLL)=(5.0 +/- 1.0) * 10^{-3}, which is more than a factor of two
larger than the leading logarithmic result B^(LL)=(2.2 +/- 0.8) * 10^{-3}.

</DOC>
<DOC>
<DOCNO> 83171 </DOCNO>
DATALOG with constraints - an answer-set programming system


  Answer-set programming (ASP) has emerged recently as a viable programming
paradigm well attuned to search problems in AI, constraint satisfaction and
combinatorics. Propositional logic is, arguably, the simplest ASP system with
an intuitive semantics supporting direct modeling of problem constraints.
However, for some applications, especially those requiring that transitive
closure be computed, it requires additional variables and results in large
theories. Consequently, it may not be a practical computational tool for such
problems. On the other hand, ASP systems based on nonmonotonic logics, such as
stable logic programming, can handle transitive closure computation efficiently
and, in general, yield very concise theories as problem representations. Their
semantics is, however, more complex. Searching for the middle ground, in this
paper we introduce a new nonmonotonic logic, DATALOG with constraints or DC.
Informally, DC theories consist of propositional clauses (constraints) and of
Horn rules. The semantics is a simple and natural extension of the semantics of
the propositional logic. However, thanks to the presence of Horn rules in the
system, modeling of transitive closure becomes straightforward. We describe the
syntax and semantics of DC, and study its properties. We discuss an
implementation of DC and present results of experimental study of the
effectiveness of DC, comparing it with CSAT, a satisfiability checker and
SMODELS implementation of stable logic programming. Our results show that DC is
competitive with the other two approaches, in case of many search problems,
often yielding much more efficient solutions.

</DOC>
<DOC>
<DOCNO> 69733 </DOCNO>
A New Property of the Quark-Antiquark Potential in a Quark-Gluon Plasma


  I consider the behavior of the quark-antiquark potential, called the Cornell
Potential, in a quark-gluon plasma. Since mesons are no longer bound in the
quark-gluon plasma, there might be a relationship between the string tension of
the quark-antiquark potential, the mass of the quark, and the coupling
constant.

</DOC>
<DOC>
<DOCNO> 10510 </DOCNO>
Gell-Mann - Low Function in the Phi^4 Theory


  An algorithm is proposed for the determination of the asymptotics of a sum of
a perturbation series from the given values of its coefficients in the
strong-coupling limit. When applied to the \Phi^4 theory, the algorithm yields
the \beta(g)\propto g^\alpha behavior with \alpha\approx 1 at large g for the
Gell-Mann - Low function.

</DOC>
<DOC>
<DOCNO> 71387 </DOCNO>
The Salpeter plasma correction for solar fusion reactions


  We review five different derivations that demonstrate that the Salpeter
formula for the plasma corrections to fusion rates is valid at the center of
the sun with insignificant errors (~ percent). We point out errors in several
recent papers that have obtained a variety of answers, some even with the wrong
sign or the wrong functional dependence.

</DOC>
<DOC>
<DOCNO> 151025 </DOCNO>
Symmetry content of a generalized p-form model of Schwarz-type in d


  We derive the vector supersymmetry and the \L-symmetry transformations for
the fields of a generalized topological $p$-form model of Schwarz-type in $d$
space-time dimensions.

</DOC>
<DOC>
<DOCNO> 10199 </DOCNO>
Phase equilibria in the polydisperse Zwanzig model of hard rods


  We study the phase behaviour of the Zwanzig model of suspensions of hard
rods, allowing for polydispersity in the lengths of the rods. In spite of the
simplified nature of the model (rods are restricted to lie along one of three
orthogonal axes), the results agree qualitatively with experimental
observations: the coexistence region broadens significantly as the
polydispersity increases, and strong fractionation occurs, with long rods found
preferentially in the nematic phase. These conclusions are obtained from an
analysis of the exact phase equilibrium equations. In the second part of the
paper, we consider the application of the recently developed ``moment free
energy method'' to the polydisperse Zwanzig model. Even though the model
contains non-conserved densities due to the orientational degrees of freedom,
most of the exactness statements (regarding the onset of phase coexistence,
spinodals, and critical points) derived previously for systems with conserved
densities remain valid. The accuracy of the results from the moment free energy
increases as more and more additional moments are retained in the description.
We show how this increase in accuracy can be monitored without relying on
knowledge of the exact results, and discuss an adaptive technique for choosing
the extra moments optimally.

</DOC>
<DOC>
<DOCNO> 13030 </DOCNO>
Rigidity of Orientationally Ordered Domains of Short Chain Molecules


  By molecular dynamics simulation, discovered is a strange rigid-like nature
for a hexagonally packed domain of short chain molecules. In spite of the
non-bonded short-range interaction potential (Lennard-Jones potential) among
chain molecules, the packed domain gives rise to a resultant global moment of
inertia. Accordingly, as two domains encounter obliquely, they rotate so as to
be parallel to each other keeping their overall structures as if they were
rigid bodies.

</DOC>
<DOC>
<DOCNO> 99514 </DOCNO>
Growth estimates on positive solutions of the equation $\Delta u + K


  We construct unbounded positive $C^2$-solutions of the equation $\Delta u + K
u^{(n + 2)/(n - 2)} = 0$ in ${\R}^n$ (equipped with Euclidean metric $g_o$)
such that $K$ is bounded between two positive numbers in ${\R}^n$, the
conformal metric $g = u^{4/(n - 2)} g_o$ is complete, and the volume growth of
$g$ can be arbitrarily fast or reasonably slow according to the constructions.
By imposing natural conditions on $u$, we obtain growth estimate on the
$L^{2n/(n - 2)}$-norm of the solution and show that it has slow decay.

</DOC>
<DOC>
<DOCNO> 13789 </DOCNO>
Spin tunnelling in mesoscopic systems


  We study spin tunnelling in molecular magnets as an instance of a mesoscopic
phenomenon, with special emphasis on the molecule Fe8. We show that the tunnel
splitting between various pairs of Zeeman levels in this molecule oscillates as
a function of applied magnetic field, vanishing completely at special points in
the space of magnetic fields, known as diabolical points. This phenomena is
explained in terms of two approaches, one based on spin-coherent-state path
integrals, and the other on a generalization of the phase integral (or WKB)
method to difference equations. Explicit formulas for the diabolical points are
obtained for a model Hamiltonian.

</DOC>
<DOC>
<DOCNO> 100186 </DOCNO>
J-holomorphic Curves, Legendre Submanifold, Reeb chords


  We prove that there exists at least one chord connecting the closed Legendre
submanifolds in a closed contact manifold with given contact form. This proves
the generalized Arnold conjecture.

</DOC>
<DOC>
<DOCNO> 119714 </DOCNO>
Multichannel interference mitigation methods in radio astronomy


  Radio-astronomical observations are increasingly corrupted by RF
interference, and online detection and filtering algorithms are becoming
essential. To facilitate the introduction of such techniques into radio
astronomy, we formulate the astronomical problem in an array signal processing
language, and give an introduction to some elementary algorithms from that
field. We consider two topics in detail: interference detection by rank
estimation of short-term covariance matrices, and spatial filtering by subspace
estimation and projection. We discuss experimental data collected at the
Westerbork radio telescope, and illustrate the effectiveness of the space-time
detection and blanking process on the recovery of a 3C48 absorption line in the
presence of GSM mobile telephony interference.

</DOC>
<DOC>
<DOCNO> 122677 </DOCNO>
Soft X-ray emission lines from a relativistic accretion disk in MCG


  XMM-Newton Reflection Grating Spectrometer (RGS) spectra of the Narrow Line
Seyfert 1 galaxies MCG -6-30-15 and Mrk 766 are physically and
spectroscopically inconsistent with standard models comprising a power-law
continuum absorbed by either cold or ionized matter. We propose that the
remarkably similar features detected in both objects in the 5 - 35 A band are
H-like oxygen, nitrogen, and carbon emission lines, gravitationally redshifted
and broadened by relativistic effects in the vicinity of a Kerr black hole. We
discuss the implications of our interpretation, and demonstrate that the
derived parameters can be physically self-consistent.

</DOC>
<DOC>
<DOCNO> 70013 </DOCNO>
A simple criterion for effects beyond hard thermal loops


  Thermal amplitudes with ultrasoft momenta, which are not accessible by
standard methods of perturbation theory, have recently attracted a lot of
interest. However, the comparison of external momenta with the ultrasoft scale
$g^2T\ln(1/g)$ is a too crude criterion, since amplitudes with hard external
momenta can also be non perturbative, if these momenta are close enough to the
light-cone. In this letter, I give a more refined criterion to decide if an
amplitude is non perturbative, that applies to all situations. In physical
terms, this condition states that non-perturbative effects appear if the
particles running in loops have to travel distances larger than their mean free
path.

</DOC>
<DOC>
<DOCNO> 80845 </DOCNO>
Geometry of 4d Simplicial Quantum Gravity with a U(1) Gauge Field


  The geometry of 4D simplicial quantum gravity with a U(1) gauge field is
studied numerically. The phase diagram shows a continuous transition when
gravity is coupled with a U(1) gauge field. At the critical point measurements
of the curvature distribution of S^4 space shows an inflated geometry with
homogeneous and symmetric nature. Also, by choosing a 4-simplex and fixing the
scalar curvature geometry of the space is measured.

</DOC>
<DOC>
<DOCNO> 170588 </DOCNO>
Quantum-limited linewidth of a good-cavity laser: An analytical theory


  The problem of the quantum-limited or intrinsic linewidth of a good-cavity
laser is revisited. Starting from the Scully-Lamb master equation, we present a
fully analytical treatment to determine the correlation function and the
  spectrum of the cavity field at steady state. For this purpose, we develop an
analytical approximation method that implicitly incorporates the microscopic
fluctuations of both the phase and intensity of the field, and, in addition,
takes full account of the saturation of the nonlinear gain. Our main result is
a simple formula for the quantum-limited linewidth that is valid from near to
far above threshold and also includes the presence of thermal photons. Close to
the threshold, the linewidth is twice as large as predicted by the standard
phase-diffusion treatment neglecting intensity fluctuations, and even 50% above
threshold the increase is still considerable. In general, quantum fluctuations
of the intensity are present and continue to influence the linewidth as long as
the photon-number distribution is not strictly Poissonian. This inherent
  relationship is displayed by a formula relating the linewidth and the Mandel
Q-parameter. More than 100% above treshold the linewidth is found to be smaller
than predicted by the standard treatment, since the simple phase-diffusion
model increasingly overestimates the rate of phase fluctuations by neglecting
gain saturation. In the limit of a very large mean photon number the expected
perfectly coherent classical field is obtained.

</DOC>
<DOC>
<DOCNO> 99569 </DOCNO>
A category for the adjoint representation


  We construct an abelian category C and exact functors in C which on the
Grothendieck group descend to the action of a simply-laced quantum group in its
adjoint representation. The braid group action in the adjoint representation
lifts to an action in the derived category of C. The category C is the direct
sum of a semisimple category and the category of modules over a certain algebra
A, associated to a Dynkin diagram. In the second half of the paper we show how
these algebras appear in the modular representation theory and in the McKay
correspondence and explore their relationship with root systems.

</DOC>
<DOC>
<DOCNO> 117438 </DOCNO>
alpha-nucleus potentials for the neutron-deficient p nuclei


  alpha-nucleus potentials are one important ingredient for the understanding
of the nucleosynthesis of heavy neutron-deficient p nuclei in the astrophysical
gamma-process where these p nuclei are produced by a series of (gamma,n),
(gamma,p), and (gamma,alpha) reactions. I present an improved alpha-nucleus
potential at the astrophysically relevant sub-Coulomb energies which is derived
from the analysis of alpha decay data and from a previously established
systematic behavior of double-folding potentials.

</DOC>
<DOC>
<DOCNO> 116954 </DOCNO>
SNS Superconducting Cavity Modeling -Iterative Learning Control


  The SNS SRF system is operated with a pulsed beam. For the SRF system to
track the repetitive reference trajectory, a feedback and a feedforward
controllers has been proposed. The feedback controller is to guarantee the
closed loop system stability and the feedforward controller is to improve the
tracking performance for the repetitive reference trajectory and to suppress
the repetitive disturbance. As the iteration number increases, the error
decreases.

</DOC>
<DOC>
<DOCNO> 71864 </DOCNO>
Associated Top-Higgs production at future colliders


  We discuss the relevance of the associated production of a Higgs boson with a
pair of top-antitop quarks at both the LHC and a future high energy e^+e^-
collider.

</DOC>
<DOC>
<DOCNO> 119513 </DOCNO>
Radio Properties of NLS1s


  While NLS1s have been studied intensively at X-ray and optical wavelengths,
comparatively little is known about their characteristics in the radio band.
Therefore, we have carried out an investigation of the radio luminosities,
source sizes, spectral index distribution, and variability of a large,
uniformly selected sample of NLS1s. Our results indicate that, in some
respects, the radio properties of NLS1s differ significantly from those of
classical Seyfert galaxies. Radio observations of NLS1s may thus provide
important clues regarding the nature of their nuclear activity.

</DOC>
<DOC>
<DOCNO> 8050 </DOCNO>
The g-factors of discrete levels in nanoparticles


  Spin-orbit scattering suppresses Zeeman splitting of individual energy levels
in small metal particles. This suppression becomes significant when the
spin-orbit scattering rate \tau_{so}^{-1} is comparable with the quantum level
spacing \delta. The g-factor exhibits mesoscopic fluctuations; at small
\delta\tau_{so} it is distributed according to the Maxwell distribution. At
\delta\tau_{so}\to 0 the average g-factor levels off at a small value
g\sim(l/L)^{1/2} given by the ratio of the electron mean free path l to the
particle size L. On the contrary, in 2D quantum dots the g-factor is strongly
enhanced by spin-orbit coupling.

</DOC>
<DOC>
<DOCNO> 69307 </DOCNO>
Extracting Weak Phase Information from B -> V_1 V_2 Decays


  We describe a new method for extracting weak, CP-violating phase information,
with no hadronic uncertainties, from an angular analysis of B -> V_1 V_2
decays, where V_1 and V_2 are vector mesons. The quantity $\sin^2 (2\beta +
\gamma)$ can be cleanly obtained from the study of decays such as B_d^0(t) ->
D^{*\pm} \rho^\mp, D^{*\pm} a_1^{\mp}, D^{*0} K^{*0}, etc. Similarly, one can
use B_s^0(t) -> D_s^{*\pm} K^{*\mp} to extract $\sin^2 \gamma$. There are no
penguin contributions to these decays. It is possible that $\sin^2 (2\beta +
\gamma)$ will be the second function of CP phases, after $\sin 2\beta$, to be
measured at B-factories.

</DOC>
<DOC>
<DOCNO> 11400 </DOCNO>
High frequency resonant experiments in Fe$_8$ molecular clusters


  Precise resonant experiments on Fe$_{8}$ magnetic clusters have been
conducted down to 1.2 K at various tranverse magnetic fields, using a
cylindrical resonator cavity with 40 different frequencies between 37 GHz and
110 GHz. All the observed resonances for both single crystal and oriented
powder, have been fitted by the eigenstates of the hamiltonian ${\cal
H}=-DS_z^2+ES_x^2-g\mu_B{\bf H}\cdot {\bf S}$. We have identified the
resonances corresponding to the coherent quantum oscillations for different
orientations of spin S = 10.

</DOC>
<DOC>
<DOCNO> 13222 </DOCNO>
Locally critical quantum phase transitions in strongly correlated metals


  When a metal undergoes a continuous quantum phase transition, non-Fermi
liquid behaviour arises near the critical point. It is standard to assume that
all low-energy degrees of freedom induced by quantum criticality are spatially
extended, corresponding to long-wavelength fluctuations of the order parameter.
However, this picture has been contradicted by recent experiments on a
prototype system: heavy fermion metals at a zero-temperature magnetic
transition. In particular, neutron scattering from CeCu$_{6-x}$Au$_x$ has
revealed anomalous dynamics at atomic length scales, leading to much debate as
to the fate of the local moments in the quantum-critical regime. Here we report
our theoretical finding of a locally critical quantum phase transition in a
model of heavy fermions. The dynamics at the critical point are in agreement
with experiment. We also argue that local criticality is a phenomenon of
general relevance to strongly correlated metals, including doped Mott
insulators.

</DOC>
<DOC>
<DOCNO> 71058 </DOCNO>
The Hard and Soft Contributions in Diffraction: A Closer Look


  Disentangle the hard and soft dynamics in diffractive DIS is one of the main
open questions of the strong interactions. We propose the study of the
logarithmic slope in $Q^2$ of the diffractive structure function as a potential
observable to discriminate between the Regge and the QCD-based approaches. Our
results indicate that a future experimental analyzes could evidentiate the
leading dynamics at $ep$ diffractive processes in the HERA kinematical regime.

</DOC>
<DOC>
<DOCNO> 85370 </DOCNO>
Brane-world inflation without inflaton on the brane


  Inspired by the Randall-Sundrum brane-world scenario, we investigate the
possibility of brane-world inflation driven not by an inflaton field on the
brane, but by a bulk, dilaton-like gravitational field. As a toy model for the
dilaton-like gravitational field, we consider a minimally coupled massive
scalar field in the bulk 5-dimensional spacetime, and look for a perturbative
solution in the anti-de Sitter (AdS) background. For an adequate range of the
scalar field mass, we find a unique solution that has non-trivial dependence on
the 5th dimensional coordinate and that induces slow-roll inflation on the
brane.

</DOC>
<DOC>
<DOCNO> 70943 </DOCNO>
Pion Decay Widths of D mesons


  The pionic decay rates of the excited $L=0,1$ $D$ mesons are calculated with
a Hamiltonian model within the framework of the covariant Blankenbecler-Sugar
{equation.} The interaction between the light quark and charm antiquark is
described by a linear scalar confining and a screened one-gluon exchange
interaction. The decay widths of the $D^*$ mesons obtain a contribution from
the exchange current that is associated with the linear scalar confining
interaction. If this contribution is taken into account along with the single
quark approximation, the calculated decay rates of the charged $D^*$ mesons are
readily below the current empirical upper limits if the axial coupling constant
of the light constituent quarks is taken to be $g_A^q$ = 0.87, but reach the
empirical upper limits if $g_A^q$ = 1. With the conventional values for
$g_A^q$, the calculated widths of the $D_1$ and $D_2^*$ mesons fall somewhat
below the experimental lower limits, leaving room for other decay modes as
well, such as $\pi\pi$ decay. The unrealistically large contribution from the
axial charge operator to the calculated pion decay width of the $D_1$ meson is
suppressed by taking into account the exchange charge effects that are
associated with the scalar linear confining and vector one-gluon exchange
interactions. The predicted values for the pionic widths of the hitherto
undiscovered L=1 $D_1^*$ and $D_0^*$ mesons are found to be smaller than
previous estimates.

</DOC>
<DOC>
<DOCNO> 68799 </DOCNO>
Towards a solution of the charmonium production controversy:


  The cross section of \chi_{cJ} hadroproduction is calculated in the
k_t-factorization approach. We find a significant contribution of the \chi_{c1}
state due to non-applicability of the Landau-Yang theorem because of off-shell
gluons. The results are in agreement with data and, in contrast to the
collinear factorization, show a dominance of the color singlet part and a
strong suppression of the color octet contribution. Our results could therefore
lead to a solution of the longstanding controversy between the color singlet
model and the color octet mechanism.

</DOC>
<DOC>
<DOCNO> 11246 </DOCNO>
Scaling of transition temerature and CuO_2 plane buckling in the cuprate


  Recently it is seen\cite{Nature},that both $\rm{T}_c$ and the buckling of the
$CuO_2$ planes goes through a maximum at the same doping level. We show that
only for optimal doping concentration the Fermi surface touches the M($0,\pi$)
point in the BZ, where the matrix element for interlayer pair tunneling
amplitude is largest, so that the gain in delocalization energy by tunneling(in
pairs) along the $c$ axis is largest. Buckling of the planes on the other hand
modulates the separation between the planes and thereby modulates the
interlayer pair tunneling amplitude. That is why both $\rm{T}_c$ and buckling
angle(Oxygen atom displacement out of the plane) scales the same way with
doping concentration. We have calculated $\rm{T}_c$ and buckling angle for
various doping concentration. The agreement with experiment is remarkably good.
We also point out the possible reason for large(about 1 percent) change of the
buckling mode phonon frequency, accross the transition temperature. scattering

</DOC>
<DOC>
<DOCNO> 14164 </DOCNO>
Completing Bethe's equations at roots of unity


  In a previous paper we demonstrated that Bethe's equations are not sufficient
to specify the eigenvectors of the XXZ model at roots of unity for states where
the Hamiltonian has degenerate eigenvalues. We here find the equations which
will complete the specification of the eigenvectors in these degenerate cases
and present evidence that the $sl_2$ loop algebra symmetry is sufficiently
powerful to determine that the highest weight of each irreducible
representation is given by Bethe's ansatz.

</DOC>
<DOC>
<DOCNO> 84425 </DOCNO>
Acceleration-Induced Nonlocal Electrodynamics in Minkowski Spacetime


  We discuss two nonlocal models of electrodynamics in which the nonlocality is
induced by the acceleration of the observer. Such an observer actually measures
an electromagnetic field that exhibits persistent memory effects. We compare
Mashhoon's model with a new ansatz developed here in the framework of charge &
flux electrodynamics with a constitutive law involving the Levi-Civita
connection as seen from the observer's local frame and conclude that they are
in partial agreement only for the case of constant acceleration.

</DOC>
<DOC>
<DOCNO> 122145 </DOCNO>
Bumpy Power Spectra and dT/T


  With the recent publication of the measurements of the radiation angular
power spectrum from the BOOMERanG Antarctic flight (de Bernardis et al. 2000),
it has become apparent that the currently favoured spatially-flat cold dark
matter model (matter density parameter $\Omega_{\rm m}=0.3$, flatness being
restored by a cosmological constant $\Omega_{\Lambda}=0.7$, Hubble parameter
$h=0.65$, baryon density parameter $\Omega_{\rm b}h^2=0.02$) no longer provides
a good fit to the data. We describe a phenomenological approach to resurrecting
this paradigm. We consider a primordial power spectrum which incorporates a
bump, arbitrarily placed at $k_{\rm b}$, and characterized by a Gaussian in log
$k$ of standard deviation $\sigma_{\rm b}$ and amplitude ${\rm A}_{\rm b}$,
that is superimposed onto a scale-invariant power spectrum. We generate a range
of theoretical models that include a bump at scales consistent with cosmic
microwave background and large-scale structure observations, and perform a
simple $\chi^2$ test to compare our models with the $COBE$ DMR data and the
recently published BOOMERanG and MAXIMA data. Unlike models that include a high
baryon content, our models predict a low third acoustic peak. We find that low
$\ell$ observations (20 $< \ell <$ 200) are a critical discriminant of the
bumps because the transfer function has a sharp cutoff on the high $\ell$ side
of the first acoustic peak...

</DOC>
<DOC>
<DOCNO> 120363 </DOCNO>
Deprojecting Sunyaev-Zeldovich statistics


  We apply the hierarchical clustering model and non-linear perturbation theory
to the cosmological density and temperature fields. This allows us to calculate
the intergalactic gas pressure power spectrum, SZ anisotropy power spectrum,
skewness and related statistics. Then we show the effect of the
non-gravitational heating. Our model confirms recent simulations yielding mass
weighted gas temperature \bar{T}_g \sim 0.35 keV and reproduces the power
spectra found in these simulations.
  While the SZ effect contains only angular information, we show that it is
possible to extract the full time resolved gas pressure power spectrum when
combined with galaxy photometric redshift surveys by using a variation on the
cross-correlation. This method further allows the disentanglement of the
gravitational and the non-gravitational heating.

</DOC>
<DOC>
<DOCNO> 99498 </DOCNO>
Diffeomorphic flows driven by Levy processes


  We prove that the stochastic differential equation $$ Y_{s,t}(x) = Y_{s,s}(x)
+ \int_0^{t-s} f(Y_{s,s+u}(x)) dX_{s+u},
  Y_{s,s}(x)=x\in\R^d. $$ driven by a L\'evy process whose paths have finite
p-variation almost surely for some $p\in[1,2)$ defines a flow of locally
C^1-diffeomorphisms provided the vector field f is $\alpha$-Lipschitz for some
$\alpha>p$. Using a path- wise approach we relax the smoothness condition
normally required for a class of discontinuous semi-martingales.

</DOC>
<DOC>
<DOCNO> 40045 </DOCNO>
First Direct Measurement of the Parity-Violating Coupling of the Z^0 to


  We have made the first direct measurement of the parity-violating coupling of
the Z^0 boson to the strange quark, A_s, using ~550,000 e^+e^- ->Z^0->hadrons
events produced with a polarized electron beam and recorded by the SLD
experiment. Z^0 -> s-sbar events were tagged by the absence of B or D hadrons
and the presence in each hemisphere of a high-momentum K^+- or K^0_s. From the
polar angle distributions of the strangeness-signed thrust axis, we obtained
A_s=0.895+-0.066(stat.)+-0.062(syst.). The analyzing power and u-ubar plus
d-dbar background were constrained using the data.

</DOC>
<DOC>
<DOCNO> 12851 </DOCNO>
T>0 properties of the infinitely repulsive Hubbard model for arbitrary


  Based on representations of the symmetric group $S_N$, explicit and exact
Schr\"odinger equation is derived for $U=\infty$ Hubbard model in any
dimensions with arbitrary number of holes, which clearly shows that during the
movement of holes the spin background of electrons plays an important role.
Starting from it, at T=0 we have analyzed the behaviour of the system depending
on the dimensionality and number of holes. Based on the presented formalism
thermodynamic quantities have also been expressed using a loop summation
technique in which the partition function is given in terms of characters of
$S_N$. In case of the studied finite systems, the loop summation have been
taken into account exactly up to the 14-th order in reciprocal temperature and
the results were corrected in higher order based on Monte Carlo simulations.
The obtained results suggest that the presented formalism increase the
efficiency of the Monte Carlo simulations as well, because the spin part
contribution of the background is automatically taken into account by the
characters of $S_N$.

</DOC>
<DOC>
<DOCNO> 116412 </DOCNO>
Enhanced dielectronic recombination of lithium-like Ti19+ ions in


  Dielectronic recombination(DR) of lithium-like Ti19+(1s2 2s) ions via 2s->2p
core excitations has been measured at the Heidelberg heavy ion storage ring
TSR. We find that not only external electric fields (0 <= Ey <= 280 V/cm) but
also crossed magnetic fields (30 mT <= Bz <= 80 mT) influence the DR via high-n
(2p_j nl)-Rydberg resonances. This result confirms our previous finding for
isoelectronic Cl14+ ions [Bartsch T et al, PRL 82, 3779 (1999)] that
experimentally established the sensitivity of DR to ExB fields. In the present
investigation the larger 2p_{1/2}-2p_{3/2} fine structure splitting of Ti19+
allowed us to study separately the influence of external fields via the two
series of Rydberg DR resonances attached to the 2s -> 2p_{1/2} and 2s ->
2p_{3/2} excitations of the Li-like core, extracting initial slopes and
saturation fields of the enhancement. We find that for Ey > 80 V/cm the field
induced enhancement is about 1.8 times stronger for the 2p_{3/2} series than
for the 2p_{1/2} series.

</DOC>
<DOC>
<DOCNO> 9510 </DOCNO>
Electron Spin Decoherence in Bulk and Quantum Well Zincblende


  A theory for longitudinal (T1) and transverse (T2) electron spin coherence
times in zincblende semiconductor quantum wells is developed based on a
non-perturbative nanostructure model solved in a fourteen-band restricted basis
set. Distinctly different dependences of coherence times on mobility,
quantization energy, and temperature are found from previous calculations.
Quantitative agreement between our calculations and measurements is found for
GaAs/AlGaAs, InGaAs/InP, and GaSb/AlSb quantum wells.

</DOC>
<DOC>
<DOCNO> 150716 </DOCNO>
Solvable Matrix Models


  We review some old and new methods of reduction of the number of degrees of
freedom from ~N^2 to ~N in the multi-matrix integrals.

</DOC>
<DOC>
<DOCNO> 174467 </DOCNO>
Measurements of Light Nuclei Production in 11.5 A GeV/c Au+Pb Heavy-Ion


  We report on measurements by the E864 experiment at the BNL-AGS of the yields
of light nuclei in collisions of Au(197) with beam momentum of 11.5 A GeV/c on
targets of Pb(208) and Pt(197). The yields are reported for nuclei with baryon
number A=1 up to A=7, and typically cover a rapidity range from y(cm) to
y(cm)+1 and a transverse momentum range of approximately 0.1 < p(T)/A < 0.5
GeV/c. We calculate coalescence scale factors B(A) from which we extract model
dependent source dimensions and collective flow velocities. We also examine the
dependences of the yields on baryon number, spin, and isospin of the produced
nuclei.

</DOC>
<DOC>
<DOCNO> 150579 </DOCNO>
Ramond-Ramond Field Transformation


  We find that the mixture of Ramond-Ramond fields and Neveu-Schwarz two form
are transformed as Majorana spinors under the T-duality group $O(d,d)$. The
Ramond-Ramond field transformation under the group $O(d,d)$ is realized in a
simple form by using the spinor representation. The Ramond-Ramond field
transformation rule obtained by Bergshoeff et al. is shown as a specific simple
example. We also give some explicit examples of the spinor representation.

</DOC>
<DOC>
<DOCNO> 119794 </DOCNO>
Equilibrium configurations of relativistic White Dwarfs


  The Feynman-Metropolis-Teller treatment for compressed atoms is here
reconsidered in the framework of the relativistic generalised Fermi-Thomas
model, obtained by Ruffini et al. Physical properties of a zero temperature
plasma is thus investigated and the resulting equation of state, which keeps
into account quantum, relativistic and electromagnetic effects, is applied to
the study of equilibrium configurations of relativistic White Dwarfs.
  It is shown that numerical evaluation of such configuration leads, for the
same central density $\rho_c$, to smaller values of radius R and of mass M than
in the classical works of Chandrasekhar and Salpeter, the deviations being most
marked at the lowest densities (up to 30% from the
  Chandrasekhar model and 10% from the Salpeter one for $\rho_c \sim
10^6g/cm^3$, corresponding to $M \sim 0.2 M_{\odot}$).
  At high densities we considered the occurrence of inverse beta decays, whose
effect is to introduce gravitational instability of the configurations. We
consequently find the maximum mass of White Dwarfs, which, for an Oxygen and an
Iron WD, is respectively $1.365 M_{\odot}$ and $1.063 M_{\odot}$.

</DOC>
<DOC>
<DOCNO> 81021 </DOCNO>
Non-Abelian Stokes theorem in action


  In this short review main issues related to the non-Abelian Stokes theorem
have been addressed. The two principal approaches to the non-Abelian Stokes
theorem, operator and two variants (coherent-state and holomorphic) of the
path-integral one, have been formulated in their simplest possible forms. A
recent generalization for a knotted loop as well as a suggestion concerning
higher-degree forms have been also included. Non-perturbative applications of
the non-Abelian Stokes theorem, to (semi-)topological gauge theories, have been
presented.

</DOC>
<DOC>
<DOCNO> 151635 </DOCNO>
Exact String Solutions in Curved Backgrounds


  We show how the classical string dynamics in $D$-dimensional curved
background can be reduced to the dynamics of a massless particle constrained on
a certain surface whenever there exists at least one Killing vector for the
background metric. Then we obtain a number of sufficient conditions, which
ensure the existence of exact solutions to the equations of motion and
constraints. The results are also relevant to the null string case. Finally, we
illustrate our considerations with an explicit example in four dimensions.

</DOC>
<DOC>
<DOCNO> 152474 </DOCNO>
T-duality of the Green-Schwarz superstring


  We study T-duality in the Green-Schwarz formalism to all orders in superspace
coordinates. We find two analogs of Buscher rules for the supervielbein and
clarify their meaning from the superstring point of view. The transformation
rules for the dilaton, spin 1/2 fermions and Ramond-Ramond superfields are also
derived.

</DOC>
<DOC>
<DOCNO> 117544 </DOCNO>
Irradiation of the secondary star in X-ray Nova Scorpii 1994 (=GRO


  We have obtained intermediate resolution optical spectra of the black-hole
candidate Nova Sco 1994 in June 1996, when the source was in an X-ray/optical
active state (R~15.05). We measure the radial velocity curve of the secondary
star and obtain a semi-amplitude of 279+/-10 km/s; a value which is 30 per cent
larger than the value obtained when the source is in quiescence. Our large
value for K_2 is consistent with 60 +9,-7 per cent of the secondary star's
surface being heated; compared to 35 per cent, which is what one would expect
if only the inner face of the secondary star were irradiated. Effects such as
irradiation-induced flows on the secondary star may be important in explaining
the observed large value for K_2.

</DOC>
<DOC>
<DOCNO> 122242 </DOCNO>
Long-Term Variability of the Low-Luminosity Active Galactic Nucleus of


  Long-term X-ray variability of the low-luminosity active galactic nucleus of
M81 was studied, using 16 ASCA observations spanning 5.5 years. The object
exhibits a factor three variation over the 5.5 years. The source intensity was
relatively constant within each observation which lasted typically for one day,
but intra-day variability by 30% was detected on the 15th observation. The
power-spectral density (PSD) was estimated in ``forward'' manner, over a
frequency range of 10^(-8.2)--10^(-4.3) Hz (period range of 1/4 day-5.5 years),
by utilizing structure function and extensive Monte-Carlo simulations in order
to overcome the very sparse and uneven data samplings. When the PSD is assumed
to be white below a "break frequency" f_b and falls off as proptional to
f^(-alpha) above f_b, where "f" is frequency and alpha is a positive parameter,
the M81 light curve is well described with 1/f_b > 800 days and alpha = 1.4 +-
0.2.

</DOC>
<DOC>
<DOCNO> 122985 </DOCNO>
Discovery of a very X-ray luminous galaxy cluster at z=0.89 in the WARPS


  We report the discovery of the galaxy cluster ClJ1226.9+3332 in the Wide
Angle ROSAT Pointed Survey (WARPS). At z=0.888 and L_X=1.1e45 erg/s (0.5-2.0
keV, h_0=0.5) ClJ1226.9+3332 is the most distant X-ray luminous cluster
currently known. The mere existence of this system represents a huge problem
for Omega_0=1 world models.
  At the modest (off-axis) resolution of the ROSAT PSPC observation in which
the system was detected, ClJ1226.9+3332 appears relaxed; an off-axis HRI
observation confirms this impression and rules out significant contamination
from point sources. However, in moderately deep optical images (R and I band)
the cluster exhibits signs of substructure in its apparent galaxy distribution.
A first crude estimate of the velocity dispersion of the cluster galaxies based
on six redshifts yields a high value of 1650 km/s, indicative of a very massive
cluster and/or the presence of substructure along the line of sight. While a
more accurate assessment of the dynamical state of this system requires much
better data at both optical and X-ray wavelengths, the high mass of the cluster
has already been unambiguously confirmed by a very strong detection of the
Sunyaev-Zel'dovich effect in its direction (Joy et al. 2001).
  Using ClJ1226.9+3332 and ClJ0152.7-1357 (z=0.835), the second-most distant
X-ray luminous cluster currently known and also a WARPS discovery, we obtain a
first estimate of the cluster X-ray luminosity function at 0.8<z<1.4 and
L_X>5e44 erg/s. Using the best currently available data, we find the comoving
space density of very distant, massive clusters to be in excellent agreement
with the value measured locally (z<0.3), and conclude that negative evolution
is not required at these luminosities out to z~1. (truncated)

</DOC>
<DOC>
<DOCNO> 8598 </DOCNO>
Quantum, Multi-Body Effects and Nuclear Reaction Rates in Plasmas


  Detailed calculations of the contribution from off-shell effects to the
quasiclassical tunneling of fusing particles are provided. It is shown that
these effects change the Gamow rates of certain nuclear reactions in dense
plasma by several orders of magnitude.

</DOC>
<DOC>
<DOCNO> 118680 </DOCNO>
Sixty-seven Additional L Dwarfs Discovered by the Two Micron All Sky


  We present JHKs photometry, far red spectra, and spectral classifications for
an additional 67 L dwarfs discovered by the Two Micron All Sky Survey. One of
the goals of this new search was to locate more examples of the latest L
dwarfs. Of the 67 new discoveries, 17 have types of L6 or later. Analysis of
these new discoveries shows that H-alpha emission has yet to be convincingly
detected in any L dwarf later than type L4.5, indicating a decline or absence
of chromospheric activity in the latest L dwarfs. Further analysis shows that
16 (and possibly 4 more) of the new L dwarfs are lithium brown dwarfs and that
the average line strength for those L dwarfs showing lithium increases until
roughly type L6.5 V then declines for later types. This disappearance may be
the first sign of depletion of atomic lithium as it begins to form into
lithium-bearing molecules. Another goal of the search was to locate nearer,
brighter L dwarfs of all subtypes. Using absolute magnitudes for 17 L dwarf
systems with trigonometric parallax measurements, we develop spectrophotometric
relations to estimate distances to the other L dwarfs. Of the 67 new
discoveries, 21 have photometric distances placing them within 25 parsecs of
the Sun. A table of all known L and T dwarfs believed to lie within 25 parsecs
- 53 in total - is also presented. Using the distance measurement of the
coolest L dwarf known, we calculate that the gap in temperature between L8 and
the warmest known T dwarfs is less than 350K and probably much less. If the
transition region between the two classes spans a very small temperature
interval, this would explain why no transition objects have yet been uncovered.
This evidence, combined with model fits to low-resolution spectra of late-M and
early-L dwarfs, indicates that L dwarfs span the range 1300K < Teff < 2000K.

</DOC>
<DOC>
<DOCNO> 120444 </DOCNO>
Convective instability in proto-neutron stars


  The linear hydrodynamic stability of proto-neutron stars (PNSs) is considered
taking into account dissipative processes such as neutrino transport and
viscosity. We obtain the general instability criteria which differ essentially
from the well-known Ledoux criterion used in previous studies. We apply the
criteria to evolutive models of PNSs that, in general, can be subject to the
various known regimes such as neutron fingers and convective instabilities. Our
results indicate that the fingers instability arises in a more extended region
of the stellar volume and lasts a longer time than expected.

</DOC>
<DOC>
<DOCNO> 99273 </DOCNO>
Topology Change and Vector Modules on Noncommutative Surfaces of


  A non associative, noncommutative algebra is defined that may be interpreted
as a set of vector modules over a noncommutative surface of rotation. Two of
these vector modules are identified with the analogues of the tangent and
cotangent spaces in noncommutative geometry, via the definition of an exterior
derivative. This derivative reduces to the standard exterior derivative in the
commutative limit. The representation of this algebra is used to investigate a
simple topology change where two connected compact surfaces coalesce to form
one such surface.

</DOC>
<DOC>
<DOCNO> 123289 </DOCNO>
Clustered vs. Isolated Star Formation


  I argue that star formation is controlled by supersonic turbulence, drawing
for support on a number of 3D hydrodynamical and MHD simulations as well as
theoretical arguments. Clustered star formation appears to be a natural result
of a lack of turbulent support, while isolated star formation is a signpost of
global turbulent support.

</DOC>
<DOC>
<DOCNO> 100827 </DOCNO>
Modeling the influence of TH1 and TH2 type cells in autoimmune diseases


  A sharp TH1/TH2 dichotomy has often been used to define the effects of
cytokines on autoimmune diseases. However contradictory results in recent
research indicate that the situation may be more complex. We build here a
simple mathematical model aimed at settling the contradictions. The model is
based on a neural network paradigm, and is applied using Partial Differential
Equations (PDE). We show here that a TH1/TH2 paradigm is only an external view
of a complex multivariate system.

</DOC>
<DOC>
<DOCNO> 10597 </DOCNO>
Scattering phases in quantum dots: an analysis based on lattice models


  The properties of scattering phases in quantum dots are analyzed with the
help of lattice models. We first derive the expressions relating the different
scattering phases and the dot Green functions. We analyze in detail the Friedel
sum rule and discuss the deviation of the phase of the transmission amplitude
from the Friedel phase at the zeroes of the transmission. The occurrence of
such zeroes is related to the parity of the isolated dot levels. A statistical
analysis of the isolated dot wave-functions reveals the absence of significant
correlations in the parity for large disorder and the appearance, for weak
disorder, of certain dot states which are strongly coupled to the leads. It is
shown that large differences in the coupling to the leads give rise to an
anomalous charging of the dot levels. A mechanism for the phase lapse observed
experimentally based on this property is discussed and illustrated with model
calculations.

</DOC>
<DOC>
<DOCNO> 119101 </DOCNO>
The Search for Cosmological Black Holes: A Surface Brightness


  Recently it has been suggested that the majority of dark matter in the
universe resides in the form of Jupiter mass black holes distributed
cosmologically. This population makes itself apparent by microlensing high
redshift quasars and introducing pronounced variability into their observed
light curves. While several arguments dismissing this hypothesis have been
presented, a conclusive observational test is, alas, sadly lacking. In this
paper we investigate the effect of a cosmologically distributed population of
microlensing masses on galaxies at low to intermediate redshift. The
magnification of bright stars in these galaxies leads to small, but observable,
fluctuations in their surface brightness. The variability time scale for
Jupiter-mass lensing objects is of the order of a few months and this
population may be detected through a future space-based monitoring campaign of
a field containing $z \sim 0.5$ galaxies. The monitoring of galactic surface
brightness will provide an effective test of the nature of dark matter on
cosmological scales.

</DOC>
<DOC>
<DOCNO> 12111 </DOCNO>
A supersymmetric mean-field approach to the infinite-U Hubbard model


  A generalized supersymmetric representation of the Hubbard operator algebra
is considered. This representation is applied to the infinite-U Hubbard model.
A mean-field theory which takes into account both on-site and inter-site
virtual boson-fermion transitions is developed. Unlike previous approaches, the
mean-field theory considered is free from divergences. Possible application of
these results to the ferromagnet-paramagnet transition, as well as to other
problems is discussed.

</DOC>
<DOC>
<DOCNO> 40660 </DOCNO>
Low-Energy Supersymmetry and the Tevatron Bottom-Quark Cross Section


  A long-standing discrepancy between the bottom-quark production cross section
and predictions of perturbative quantum chromodynamics is addressed. We show
that pair production of light gluinos, of mass 12 to 16 GeV, with two-body
decays into bottom quarks and light bottom squarks, yields a bottom-quark
production rate in agreement with hadron collider data. We examine constraints
on this scenario from low-energy data and make predictions that may be tested
at the next run of the Fermilab Tevatron Collider.

</DOC>
<DOC>
<DOCNO> 121569 </DOCNO>
Optical Spectra of Type Ia Supernovae at z=0.46 and z=1.2


  We present optical spectra, obtained with the Keck 10-m telescope, of two
high-redshift type Ia supernovae (SNe Ia) discovered by the High-z Supernova
Search Team: SN 1999ff at z=0.455 and SN 1999fv at z~1.2, the highest-redshift
published SN Ia spectrum. Both SNe were at maximum light when the spectra were
taken. We compare our high-z spectra with low-z normal and peculiar SNe Ia as
well as with SNe Ic, Ib, and II. There are no significant differences between
SN 1999ff and normal SNe Ia at low redshift. SN 1999fv appears to be a SN Ia
and does not resemble the most peculiar nearby SNe Ia.

</DOC>
<DOC>
<DOCNO> 120368 </DOCNO>
A Search for Extended Line Emission from BALQSOs


  We have obtained HST NICMOS snapshot images of ten BALQSOs and four
radio-quiet non-BALQSOs to search for extended narrow-line regions. For each
object we obtained an image in the F160W filter and a narrow-band image in
either H-alpha, H-beta, or [O ii]. We find no detections of extended
narrow-line emission in the sample. We generate simulated images of QSOs with
extended narrow-line regions to place limits on the amount of flux that may be
present, and we conclude that BALQSOs cannot be more than several times
brighter in extended emission than typical type 2 AGN. Spatially unresolved
H-alpha emission is detected in all nine objects observed in this line, which
we attribute to broad H-alpha emission. The five detected BALQSOs have derived
H-alpha equivalent widths that are larger than those of the four non-BALQSOs by
a factor of around 2 on average. This may point to an intrinsic difference
between the rest-frame optical spectral properties of BALQSOs and non-BALQSOs.

</DOC>
<DOC>
<DOCNO> 72159 </DOCNO>
On equations for neutrino propagation in matter


  We study the dynamical equations for two-family neutrino oscillations in a
medium of continuously-varying density. We can find explicit solutions to these
equations in terms of series of nested integrals. These solutions can serve as
a basis for numerical calculation of these processes or for further study of
their analytical properties.

</DOC>
<DOC>
<DOCNO> 67678 </DOCNO>
Families as Neighbors in Extra Dimension


  We propose a new mechanism for explanation of the fermion hierarchy without
introducing any family symmetries. Instead, we postulate that different
generations live on different branes embedded in a relatively large extra
dimension, where the gauge fields can propagate. The electroweak symmetry is
broken on a separate brane, which is a source of exponentially decaying Higgs
profile in the bulk. The resulting fermion masses and mixings are determined by
an exponentially suppressed overlap of the fermion and Higgs wave functions and
are automatically hierarchical even if all copies are identical and there is no
hierarchy of distances. In this framework the well known pattern of the
"nearest neighbor mixing" is predicted due to the fact that the families are
literally neighbors in the extra space. This picture may also provide a new way
of a hierarchically weak supersymmetry breaking, provided that the combination
of three family branes is a non-BPS configuration, although each of them,
individually taken, is. This results in exponentially weak supersymmetry
breaking. We also discuss the issue of embedding identical branes in the
compact spaces and localization of the fermionic zero modes.

</DOC>
<DOC>
<DOCNO> 169868 </DOCNO>
Renormalization Group in Quantum Mechanics


  We establish the renormalization group equation for the running action in the
context of a one quantum particle system. This equation is deduced by
integrating each fourier mode after the other in the path integral formalism.
It is free of the well known pathologies which appear in quantum field theory
due to the sharp cutoff. We show that for an arbitrary background path the
usual local form of the action is not preserved by the flow. To cure this
problem we consider a more general action than usual which is stable by the
renormalization group flow. It allows us to obtain a new consistent
renormalization group equation for the action.

</DOC>
<DOC>
<DOCNO> 122334 </DOCNO>
Large-scale distribution and spectral properties of galaxies in the


  We present the results of a redshift survey of both cluster and intercluster
galaxies in the central part of the Shapley Concentration, the richest
supercluster of clusters in the nearby Universe, consisting of ~2000 radial
velocities.
 We estimate the total overdensity in galaxies of the supercluster and its mass
and we discuss the cosmological implications of these results.
 Moreover, using a Principal Components Analysis technique, we study the
influence of the cluster and supercluster dynamics on the galaxy spectral
morphology.

</DOC>
<DOC>
<DOCNO> 68875 </DOCNO>
A New Approach to Texture Analysis of Quark Mass Matrices


  The triangular basis is proposed as an efficient way of analyzing general
quark mass matrices. Applying the method to hermitian hierarchical matrices
with five texture zeros, analytic predictions for quark mixing can be readily
obtained. One unique texture pair is found most favorable with present data.
Some remarks are also made concerning parallel textures between the up and down
quark mass matrices with four zeros.

</DOC>
<DOC>
<DOCNO> 40277 </DOCNO>
Recent Results Addressing the KARMEN Timing Anomaly


  Recent resuls from experiments at Fermilab and the Paul Scherrer Institute
have constrained the parameter space available for a hypothetical particle
$Q^0$ produced in the decay $\pi^+ \to \mu^+ Q^0$. This decay has been invoked
to explain a peculiar feature of an event arrival time distribution observed in
the KARMEN neutrino experiment.

</DOC>
<DOC>
<DOCNO> 102903 </DOCNO>
Energy bounds for the spinless Salpeter equation: harmonic oscillator


  We study the eigenvalues E_{n\ell} of the Salpeter Hamiltonian H =
\beta\sqrt(m^2 + p^2) + vr^2, v>0, \beta > 0, in three dimensions. By using
geometrical arguments we show that, for suitable values of P, here provided,
the simple semi-classical formula E = min_{r > 0} {v(P/r)^2 + \beta\sqrt(m^2 +
r^2)} provides both upper and lower energy bounds for all the eigenvalues of
the problem.

</DOC>
<DOC>
<DOCNO> 40508 </DOCNO>
The Belle Silicon Vertex Detector


  The silicon vertex detector of the Belle experiment has been built to provide
the vertex information of $B$ meson decays at the KEKB accelerator. Performance
during the initial data taking period and a brief description of the upgrade
plan are also presented.

</DOC>
<DOC>
<DOCNO> 99308 </DOCNO>
Polynomial and rational solutions of holonomic systems


  The aim of this paper is to give two new algorithms, which are elimination
free, to find polynomial and rational solutions for a given holonomic system
associated to a set of linear differential operators in the Weyl algebra D =
k<x_1, ..., x_n, dx_1, ..., dx_n> where k is a subfield of the complex numbers.

</DOC>
<DOC>
<DOCNO> 12247 </DOCNO>
Efficient calculation of imaginary time displaced correlation functions


  The calculation of imaginary time displaced correlation functions with the
auxiliary field projector quantum Monte-Carlo algorithm provides valuable
insight (such as spin and charge gaps) in the model under consideration. One of
the authors and M. Imada [F.F. Assaad and M. Imada, J. Phys. Soc. Jpn. 65 189
(1996).] have proposed a numerically stable method to compute those quantities.
Although precise this method is expensive in CPU time. Here, we present an
alternative approach which is an order of magnitude quicker, just as precise,
and very simple to implement. The method is based on the observation that for a
given auxiliary field the equal time Green function matrix, $G$, is a
projector: $G^2 = G$.

</DOC>
<DOC>
<DOCNO> 117390 </DOCNO>
Generation of the Primordial Magnetic Fields during Cosmological


  We investigate the generation of magnetic field by the Biermann battery in
cosmological ionization fronts, using new simulations of the reionization of
the universe by stars in protogalaxies. Two mechanisms are primarily
responsible for magnetogenesis: i) the breakout of I-fronts from protogalaxies,
and ii) the propagation of I-fronts through the high density neutral filaments
which are part of the cosmic web. The first mechanism is dominant prior to
overlapping of ionized regions (z ~ 7), whereas the second continues to operate
even after that epoch. However, after overlap the field strength increase is
largely due to the gas compression occurring as cosmic structures form. As a
consequence, the magnetic field at z ~ 5 closely traces the gas density, and it
is highly ordered on megaparsec scales. The mean mass-weighted field strength
is B_0 ~ 10^{-19} G in the simulation box. There is a relatively well-defined,
nearly linear correlation between B_0 and the baryonic mass of virialized
objects, with B_0 ~ 10^{-18} G in the most massive objects (M ~ 10^9 M_sun) in
our simulations. This is a lower limit, as lack of numerical resolution
prevents us from following small scale dynamical processes which could amplify
the field in protogalaxies. Although the field strengths we compute are
probably adequate as seed fields for a galactic dynamo, the field is too small
to have had significant effects on galaxy formation, on thermal conduction, or
on cosmic ray transport in the intergalactic medium. It could, however, be
observed in the intergalactic medium through innovative methods based on
analysis of gamma-ray burst photon arrival times.

</DOC>
<DOC>
<DOCNO> 118567 </DOCNO>
Dark Matter Problem in Disk Galaxies


  In the generic CDM cosmogony, dark-matter halos emerge too lumpy and
centrally concentrated to host observed galactic disks. Moreover, disks are
predicted to be smaller than those observed. We argue that the resolution of
these problems may lie with a combination of the effects of protogalactic
disks, which would have had a mass comparable to that of the inner dark halo
and be plausibly non-axisymmetric, and of massive galactic winds, which at
early times may have carried off as many baryons as a galaxy now contains. A
host of observational phenomena, from quasar absorption lines and intracluster
gas through the G-dwarf problem point to the existence of such winds. Dynamical
interactions will homogenize and smooth the inner halo, and the observed disk
will be the relic of a massive outflow. The inner halo expanded after absorbing
energy and angular momentum from the ejected material. Observed disks formed at
the very end of the galaxy formation process, after the halo had been reduced
to a minor contributor to the central mass budget and strong radial streaming
of the gas had died down.

</DOC>
<DOC>
<DOCNO> 152207 </DOCNO>
The M2-brane Solution of Heterotic M-theory with the Gauss-Bonnet R^2


  We consider the effective action of M-theory compactified on a S^1/Z_2
orbifold with R^2 interaction in the Gauss-Bonnet combination. We derive
equations of motion with source terms arising from the Gauss-Bonnet terms and
find the M2-brane solution up to order \kappa^{2/3}. It receives a correction
which depends on the orbifold coordinate in the same form as the gauge 5-brane
solution.

</DOC>
<DOC>
<DOCNO> 117717 </DOCNO>
The deuterium abundance in QSO absorption systems: a mesoturbulent


  A new method, based on simulated annealing technique and aimed at the inverse
problem in the analysis of intergalactic or interstellar complex spectra of
hydrogen and metal lines, is outlined. We consider the process of line
formation in clumpy stochastic media accounting for fluctuating velocity and
density fields self-consistently. Two examples of the analysis of `H+D'-like
absorptions seen at z = 3.514 and 3.378 towards APM 08279+5255 are presented.

</DOC>
<DOC>
<DOCNO> 116457 </DOCNO>
Novel approach for spin-flipping a stored polarized beam


  The traditional method of spin-flipping a stored polarized beam is based on
slowly crossing an rf induced depolarizing resonance. This paper discusses a
novel approach where the polarization reversal is achieved by trapping the beam
polarization into a stable spin-flipping motion on top of the rf induced
resonance at a half-revolution frequency.

</DOC>
<DOC>
<DOCNO> 117879 </DOCNO>
Gamma-Ray Bursts via the Neutrino Emission from Heated Neutron Stars


  A model is proposed for gamma-ray bursts based upon a neutrino burst of about
10^52 ergs lasting a few seconds above a heated collapsing neutron star. This
type of thermal neutrino burst is suggested by relativistic hydrodynamic
studies of the compression, heating, and collapse of close binary neutron stars
as they approach their last stable orbit, but may arise from other sources as
well. We present a hydrodynamic simulation of the formation and evolution of
the pair plasma associated with such a neutrino burst. This pair plasma leads
to the production of ~10^51 - 10^52 ergs in gamma-rays with spectral and
temporal properties consistent with observed gamma-ray bursts.

</DOC>
<DOC>
<DOCNO> 152217 </DOCNO>
A Dynamical Brane in the Gravitational Dual of ${\cal N}=2$ $Sp(N)$


  The particular model of d5 higher derivative gravity which is dual to ${\cal
N}=2$ $Sp(N)$ SCFT is considered. A (perturbative) AdS black hole in such
theory is constructed in the next-to-leading order of the AdS/CFT
correspondence. The surface counterterms are fixed by the conditions required
for a well-defined variational procedure and the finiteness of AdS space (when
the brane goes to infinity). A dynamical brane is realized at the boundary of
an AdS black hole with a radius that is larger than the horizon radius. The
AdS/CFT correspondence dictates the parameters of the gravitational dual in
such a way that the dynamical brane (the observable universe) always occurs
outside the horizon.

</DOC>
<DOC>
<DOCNO> 151304 </DOCNO>
Symmetrization of the Berezin Star Product and Multiple Star Product


  We construct a multiple star product method and by using this method, show
that integral forms of some star products can be written in terms of the
path-integral. This method can be applied to some examples. Especially, the
associativity of the skew-symmetrized Berezin star product proposed in
\cite{SW}, is recovered in large $N$ limit of the multiple star product. We
also derive the path integral form of the Kontsevich star product from the
multiple Moyal star product. This paper includes some reviews about star
products.

</DOC>
<DOC>
<DOCNO> 85248 </DOCNO>
M{\o}ller Energy for the Kerr-Newman metric


  The energy distribution in the Kerr-Newman space-time is computed using the
M{\o}ller energy-momentum complex. This agrees with the Komar mass for this
space-time obtained by Cohen and de Felice. These results support the
Cooperstock hypothesis.

</DOC>
<DOC>
<DOCNO> 99317 </DOCNO>
On the Hydrodynamic Equilibrium of a Rod in a Lattice Fluid


  We model the behavior of a big (Brazil) nut in a medium of smaller nuts with
a stochastic asymmetric simple exclusion dynamics of a polymer-monomer lattice
system. The polymer or `rod' can move up or down in an external negative field,
occupying N horizontal lattice sites where the monomers cannot enter. The
monomers (at most one per site) or `fluid particles' are moving symmetrically
in the horizontal plane and asymmetrically in the vertical direction, also with
a negative field. For a fixed position of the rod, this lattice fluid is in
equilibrium with a vertical height profile reversible for the monomers' motion.
Upon `shaking' (speeding up the monomers) the motion of the `rod' dynamically
decouples from that of the monomers resulting in a reversible random walk for
the rod around an average height proportional to log N.

</DOC>
<DOC>
<DOCNO> 9520 </DOCNO>
Low energy collective modes, Ginzburg-Landau theory, and pseudogap


  We study the superconducting instability in systems with long but finite
ranged, attractive, pairing interactions. We show that such long-ranged
superconductors exhibit a new class of fluctuations in which the internal
structure of the Cooper pair wave function is soft, and thus lead to
"pseudogap" behavior in which the actual transition temperature is greatly
depressed from its mean field value. These fluctuations are {\it not} phase
fluctuations of the standard superconducting order parameter, and lead to a
highly unusual Ginzburg-Landau description. We suggest that the crossover
between the BCS limit of a short-ranged attraction and our problem is of
interest in the context of superconductivity in the underdoped cuprates.

</DOC>
<DOC>
<DOCNO> 8231 </DOCNO>
Mechanical detection of nuclear spin relaxation in a micron-size crystal


  A room temperature nuclear magnetic resonance force microscope (MRFM), fitted
in a $^1$Tesla electromagnet, is used to measure the nuclear spin relaxation of
$^1$H in a micron-size (70ng) crystal of ammonium sulfate. NMR sequences,
combining both pulsed and continuous wave r.f. fields, have allowed us to
measure mechanically $T_2$ and $T_1$, the transverse and longitudinal spin
relaxation times. Because two spin species with different $T_1$ values are
measured in our $7\mu{\rm m}$ thick crystal, magnetic resonance imaging of
their spatial distribution inside the sample section are performed. To
understand quantitatively the measured signal, we carefully study the influence
of the spin-lattice relaxation and the non-adiabaticity of the c.w. sequence on
the intensity and time dependence of the detected signal.

</DOC>
<DOC>
<DOCNO> 8881 </DOCNO>
Spin-orbit coupling in interacting quasi-one-dimensional electron


  We present a new model for the study of spin-orbit coupling in interacting
quasi-one-dimensional systems and solve it exactly to find the spectral
properties of such systems. We show that the combination of spin-orbit coupling
and electron-electron interactions results in: the replacement of separate spin
and charge excitations with two new kinds of bosonic mixed-spin-charge
excitation, and a characteristic modification of the spectral function and
single-particle density of states. Our results show how manipulation of the
spin-orbit coupling, with external electric fields, can be used for the
experimental determination of microscopic interaction parameters in quantum
wires.

</DOC>
<DOC>
<DOCNO> 40301 </DOCNO>
A New Measurement of the Radiative Ke3 Branching Ratio and Photon


  We present a preliminary report on a new measurement of the radiative neutral
Ke3 branching ratio and the first study of the photon spectrum in this decay.
We find BR(Ke3g, E*_g>30 GeV, Th*_eg>20 deg)/BR(Ke3) =
0.911+-0.009(stat)+0.021-0.010(syst)%. Our measurement of the spectrum is
consistent with inner bremsstrahlung only as the source of photons at the 2
sigma level.

</DOC>
<DOC>
<DOCNO> 101584 </DOCNO>
The Dynamics of a Vertically Transmitted Disease


  An SIRS epidemiological model for a vertically transmitted disease is
discussed. We give a complete global analysis in terms of three explicit
threshold parameters which respectively govern the existence and stability of
an endemic proportion equilibrium, the increase of the total population and the
growth of the infective population. This paper gereralize the results of
Busenberg and van den Driessche.

</DOC>
<DOC>
<DOCNO> 80813 </DOCNO>
Lattice hadron matrix elements with the Schroedinger functional: the


  We present the results of a non-perturbative determination of the pion matrix
element of the twist-2 operator corresponding to the average momentum of
non-singlet quark densities. The calculation is made within the Schroedinger
functional scheme. We report the results of simulations done with the standard
Wilson action and with the non-perturbatively improved clover action and we
show that their ratio correctly extrapolates, in the continuum limit, to a
value compatible with the residual correction factor expected from perturbation
theory.

</DOC>
<DOC>
<DOCNO> 71092 </DOCNO>
The V-A sum rules and the Operator Product Expansion in complex


  The operator product expansion (OPE) for the difference of vector and axial
current correlators is analyzed for complex values of momentum q^2. The vector
and axial spectral functions, taken from hadronic tau-decay data, are treated
with the help of Borel, Gaussian and spectral moments sum rules. The range of
applicability, advantages and disadvantages of each type are discussed. The
general features of OPE are confirmed by the data. The vacuum expectation
values of dimension 6 and 8 operators are found to be O_6=-(6.8\pm 2.1)*10^{-3}
GeV^6, O_8=(7\pm 4)*10^{-3} GeV^8.

</DOC>
<DOC>
<DOCNO> 11271 </DOCNO>
Comment on "Liquid Limits: The Glass Transition and Liquid-Gas Spinodal


  In ref. cond-mat/0005372, Sastry studies by numerical simulations the phase
diagram of a simple fragile glass-forming liquid, presenting very interesting
and clear results. We apply to this system, at various density values, the
analytic approach to structural glass thermodynamics recently introduced and we
compare our theoretical predictions on the liquid-glass transition temperature
with Sastry's data.

</DOC>
<DOC>
<DOCNO> 70056 </DOCNO>
Transversality of the logarithmic divergences in the Classical Finite


  We show that the logarithmic divergences that appear in the classical
approximation of the finite temperature SU(N) self-energy are transverse. We
use the Ward identities in linear gauges and the fact that the superficial
degree of divergence d of a classical diagram only depends on the number of
loops l via d=2-l. We comment on the relevance of this result to the
construction of a low-energy effective theory beyond HTLs.

</DOC>
<DOC>
<DOCNO> 151547 </DOCNO>
Finite Temperature Tunneling and Phase Transitions in SU(2)-Gauge Theory


  A pure Yang-Mills theory extended by addition of a quartic term is considered
in order to study the transition from the quantum tunneling regime to that of
classical, i.e. thermal, behaviour. The periodic field configurations are
found, which interpolate between the vacuum and sphaleron field configurations.
It is shown by explicit calculation that only smooth second order transitions
occur for all permissible values of the parameter $\L$ introduced with the
quartic term. The theory is one of the rare cases which can be handled
analytically.

</DOC>
<DOC>
<DOCNO> 70550 </DOCNO>
g_1 at low x and low Q^2 with Polarized ep Colliders


  Measurements of g_1 at low x and low Q^2 are expected to provide a sensitive
probe of the transition from Regge to perturbative QCD dynamics, offering a new
testing ground for models of small x physics. We discuss the potential of
polarized ep colliders (Polarized HERA and eRHIC) to investigate this physics
--- varying Q^2 between 0.01 and 1 GeV^2 --- and to constrain the high-energy
part of the Drell-Hearn-Gerasimov sum-rule for polarized photoproduction.

</DOC>
<DOC>
<DOCNO> 99930 </DOCNO>
The uniqueness of the solution to inverse problems of interpolation of


  We prove that an interpolation pair of Banach lattices is uniquely determined
by the collection of intermediate spaces with the property that these are
interpolation spaces for positive operators. A correspondent result for exact
interpolation is also presented.

</DOC>
<DOC>
<DOCNO> 101692 </DOCNO>
Herrero's Approximation Problem for Quasidiagonal Operators


  Let T be a quasidiagonal operator on a separable Hilbert space. Then T is the
norm limit of operators, each of which generate a finite dimensional
C*-algebra, if and only if the C*-algebra generated by T is exact.

</DOC>
<DOC>
<DOCNO> 102135 </DOCNO>
Uniform Exponential Growth of Polycyclic Groups


  We prove that polycyclic groups are of polynomial growth or of uniform
exponential growth.

</DOC>
<DOC>
<DOCNO> 122483 </DOCNO>
The effects of vertical outflows on disk dynamos


  We consider the effect of vertical outflows on the mean-field dynamo in a
thin disk. These outflows could be due to winds or magnetic buoyancy. We
analyse both two-dimensional finite-difference numerical solutions of the
axisymmetric dynamo equations and a free-decay mode expansion using the
thin-disk approximation. Contrary to expectations, a vertical velocity can
enhance dynamo action, provided it is not too strong. In the nonlinear regime
this can lead to super-exponential growth of the magnetic field.

</DOC>
<DOC>
<DOCNO> 119087 </DOCNO>
Cosmological constraints from the correlation function of galaxy


  I compare various semi-analytic models for the bias of dark matter halos with
halo clustering properties observed in recent numerical simulations. The best
fitting model is one based on the collapse of ellipsoidal perturbations
proposed by Sheth, Mo & Tormen (1999), which fits the halo correlation length
to better than 8 per cent accuracy. Using this model, I confirm that the
correlation length of clusters of a given separation depends primarily on the
shape and amplitude of mass fluctuations in the universe, and is almost
independent of other cosmological parameters. Current observational
uncertainties make it difficult to draw robust conclusions, but for
illustrative purposes I discuss the constraints on the mass power spectrum
which are implied by recent analyses of the APM cluster sample. I also discuss
the prospects for improving these constraints using future surveys such as the
Sloan Digital Sky Survey. Finally, I show how these constraints can be combined
with observations of the cluster number abundance to place strong limits on the
matter density of the universe.

</DOC>
<DOC>
<DOCNO> 178467 </DOCNO>
Roles of quark-pair correlations in baryon structure and non-leptonic


  Roles of quark-pair correlations in the baryon structure and the hyperon
non-leptonic weak decay are studied within the non-relativistic constituent
quark model. We construct the SU(3) ground state baryons by solving the three
body problem rigorously with the confinement force and the short range
spin-dependent attraction. We emphasize the importance of the $s=0$ quark-quark
correlation to reproduce the $\Delta I=1/2$ enhancement of the hyperon decay,
and demonstrate that resulting static properties as well as the decay
amplitudes agree with the experiments, if we deal with the $s=0$ correlation
properly. Special attention is also put on the consequences of the SU(6)
spin-flavor symmetry breaking due to the $s=0$ correlation. Calculated magnetic
moments are the almost same as the naive SU(6) predictions in spite of the
existence of the strong correlations.

</DOC>
<DOC>
<DOCNO> 69056 </DOCNO>
T-Odd Triple-Product Correlations in Hadronic b Decays


  We study T-violating triple-product asymmetries in the quark-level decay b ->
s u u(bar) within the standard model (SM). We find that only two types of
triple products are non-negligible. The asymmetry in p_u . [s_u x s_u(bar)] or
p_u(bar) . [s_u x s_u(bar)] can be as large as about 5%. It can be probed in B
-> V_1 V_2 decays, where V_1 and V_2 are vector mesons. And the asymmetry in
s_b . [p_u x p_s] can be in the range 1%--3%. One can search for this signal in
the decay \Lambda_b -> \Lambda \pi^+ \pi^- or in B^* -> X_s X, where X_s and X
then each decay into two mesons. All other triple-product asymmetries are
expected to be small within the SM. This gives us new methods of searching for
new physics.

</DOC>
<DOC>
<DOCNO> 170784 </DOCNO>
Quantum simulated annealing


  The question of whether or not quantum computers can efficiently solve
NP-complete problems is open, although indications are that BQP does not
contain NP. Still, many of these problems are natural candidates for solution
on quantum computers. We outline a thermodynamical formalism for the traveling
salesman problem which allows for its expected polytime solution on a quantum
computer with probability arbitrarily close to unity, given sufficient energy
resources and subject to a weak nondegeneracy constraint on the distances.
Applications to other problems are also discussed.

</DOC>
<DOC>
<DOCNO> 117134 </DOCNO>
Coordinate-space approach to the bound-electron self-energy: Self-Energy


  The self-energy screening correction is evaluated in a model in which the
effect of the screening electron is represented as a first-order perturbation
of the self energy by an effective potential. The effective potential is the
Coulomb potential of the spherically averaged charge density of the screening
electron. We evaluate the energy shift due to a $1s_{1/2}$, $2s_{1/2}$,
$2p_{1/2}$, or $2p_{3/2}$ electron screening a $1s_{1/2}$, $2s_{1/2}$,
$2p_{1/2}$, or $2p_{3/2}$ electron, for nuclear charge Z in the range $5 \le
Z\le 92$. A detailed comparison with other calculations is made.

</DOC>
<DOC>
<DOCNO> 72181 </DOCNO>
High energy photon-neutrino elastic scattering


  The one-loop helicity amplitudes for the elastic scattering process
$\gamma\nu\to\gamma\nu$ in the Standard Model are computed at high center of
mass energies. A general decomposition of the amplitudes is utilized to
investigate the validity of some of the key features of our results. In the
center of mass, where $\sqrt{s} = 2\omega$, the cross section grows roughly as
$\omega^6$ to near the threshold for $W$-boson production, $\sqrt{s} = m_W$.
Although suppressed at low energies, we find that the elastic cross section
exceeds the cross section for $\gamma\nu\to\gamma\gamma\nu$ when $\sqrt{s}>13 $
GeV. We demonstrate that the scattered photons are circularly polarized and the
net value of the polarization is non-zero. Astrophysical implications of high
energy photon-neutrino scattering are discussed.

</DOC>
<DOC>
<DOCNO> 13076 </DOCNO>
Island phases and charge order in two-dimensional manganites


  The ferromagnetic Kondo lattice model with an antiferromagnetic interaction
between localized spins is a minimal description of the competing kinetic t and
magnetic K energy terms which generate the rich physics of manganite systems.
Motivated by the discovery in one dimension of homogeneous ``island phases'',
we consider the possibility of analogous phases in higher dimensions. We
characterize the phases present at commensurate fillings, and consider in
detail the effects of phase separation in all filling and parameter regimes. We
deduce that island and flux phases are stable for intermediate values of K/t at
the commensurate fillings n = 1/4, 1/3, 3/8, and 1/2. We discuss the connection
of these results to the charge and magnetic ordering observed in a wide variety
of manganite compounds.

</DOC>
<DOC>
<DOCNO> 11101 </DOCNO>
Electrical transport properties of bulk Ni$_{c}$Fe$_{1-c}$ alloys and


  Within the Kubo-Greenwood formalism we use the fully relativistic,
spin-polarized, screened Korringa-Kohn-Rostoker method together with the
coherent-potential approximation for layered systems to calculate the
resistivity for the permalloy series Ni$_{c}$Fe$_{1-c}$. We are able to
reproduce the variation of the resistivity across the entire series; notably
the discontinuous behavior in the vicinity of the structural phase transition
from bcc to fcc. The absolute values for the resistivity are within a factor of
two of the experimental data. Also the giant magnetoresistance of a series of
permalloy-based spin-valve structures is estimated; we are able to reproduce
the trends and values observed on prototypical spin-valve structures.

</DOC>
<DOC>
<DOCNO> 121500 </DOCNO>
Clusters of Galaxies at High Redshift: The LMT/GTM Perspective


  The lack of reliable cluster samples at intermediate and high redshift has
motivated many optical/infrared and X-ray cluster searches. The motivation of
such searches is well justified: the abundance of massive collapsed regions
gives a direct constraint on Omega(matter). Alternatively, the
Sunyaev-Zeldovich effect (SZE) offers a robust method for the detection of
clusters which is, almost, independent of redshift. In this paper we comment on
the possibility of mapping the SZE at high resolution in the millimeter regime
using the Large Millimeter Telescope/Gran Telescopio Milimetrico (LMT/GTM) and
the bolometer array BOLOCAM. The construction of the LMT/GTM facility is
underway atop Cerro La Negra (latitude=18deg 59min; height=4600 m) in Mexico.

</DOC>
<DOC>
<DOCNO> 9560 </DOCNO>
Compact fields and mass generation


  It is shown that the free propagator of an angular, i.e. compact, field with
zero lagrangian mass acquires a nonzero propagator mass $\omega$
(`kinematical' mass generation). To demonstrate this effect the free propagator
of the goldstone boson in an O(2) model with spontaneous symmetry breaking
is calculated. It is shown that this propagator is massive, the mass $\omega$
being a function of the scalar `condensate' ${\bar\phi}$.

</DOC>
<DOC>
<DOCNO> 170490 </DOCNO>
A potential multipartide entanglement measure


  We discuss entanglement of multiparticle quantum systems. We propose a
potential measure of a type of entanglement of pure states of n qubits, the
n-tangle. For a system of two qubits the n-tangle is equal to the square of the
concurrence, and for systems of three qubits it is equal to the ''residual
entanglement''. We show that the n -tangle, is also equal to the generalization
of concurrence squared for even n, and use this fact to prove that the n-tangle
is an entanglement monotone. However, the n-tangle is undefined for odd n>3.
Finally we propose a measure related to the n-tangle for mixed state systems of
n qubits, and find an analytical formula for this measure for even n.

</DOC>
<DOC>
<DOCNO> 71015 </DOCNO>
Recoil Order Chiral Corrections to Baryon Octet Axial Currents


  We calculate chiral corrections to the octet axial currents through ${\cal
O}(p^3)$ using baryon chiral perturbation theory (BCPT). The relativistic BCPT
framework allows one to sum an infinite series of recoil corrections at a given
order in the chiral expansion. We also include SU(3)-breaking operators
occuring at ${\cal O}(p^2)$ not previously considered. We determine the
corresponding low-energy constants (LEC's) from hyperon semileptonic decay data
using a variety of infrared regularization schemes. We find that the chiral
expansion of the axial currents does not display the proper convergence
behavior, regardless of which scheme is chosen. We explore the implications of
our analysis for determinations of the strange quark contribution to the
nucleon spin, $\Delta s$.

</DOC>
<DOC>
<DOCNO> 11501 </DOCNO>
Comment on "Magnetoresistance and differential conductance in


  Jeong-O Lee et al. [Phy. Rev. B, 61, R16 362 (2000)] reported
magnetoresistance and differential conductance measurements of multiwalled
carbon nanotubes. The observed aperiodic conductance fluctuations and the
negative magnetoresistance was interpreted to originate exclusively from
changes in the density of states at the Fermi energy. We show that this
interpretation is questionable and not supported by their measurements.

</DOC>
<DOC>
<DOCNO> 170371 </DOCNO>
A finite-dimensional representation of the quantum angular momentum


  A useful finite-dimensional matrix representation of the derivative of
periodic functions is obtained by using some elementary facts of trigonometric
interpolation. This NxN matrix becomes a projection of the angular derivative
into polynomial subspaces of finite dimension and it can be interpreted as a
generator of discrete rotations associated to the z-component of the projection
of the angular momentum operator in such subspaces, inheriting thus some
properties of the continuum operator. The group associated to these discrete
rotations is the cyclic group of order N. Since the square of the quantum
angular momentum L^2 is associated to a partial differential boundary value
problem in the angular variables $\theta$ and $\phi$ whose solution is given in
terms of the spherical harmonics, we can project such a differential equation
to obtain an eigenvalue matrix problem of finite dimension by extending to
several variables a projection technique for solving numerically two point
boundary value problems and using the matrix representation of the angular
derivative found before. The eigenvalues of the matrix representing L^2 are
found to have the exact form n(n+1), counting the degeneracy, and the
eigenvectors are found to coincide exactly with the corresponding spherical
harmonics evaluated at a certain set of points.

</DOC>
<DOC>
<DOCNO> 117889 </DOCNO>
Testing the connection between the X-ray and submillimetre source


  The powerful combination of the Chandra X-ray telescope, the SCUBA
submillimetre-wave camera and the gravitational lensing effect of the massive
galaxy clusters A2390 and A1835 has been used to place stringent X-ray flux
limits on six faint submillimetre SCUBA sources and deep submillimetre limits
on three Chandra sources which lie in fields common to both instruments. One
further source is marginally detected in both the X-ray and submillimetre
bands. For all the SCUBA sources our results are consistent with
starburst-dominated emission. For two objects, including SMMJ14011+0252 at
z=2.55, the constraints are strong enough that they can only host powerful
active galactic nuclei if they are both Compton-thick and any scattered X-ray
flux is weak or itself absorbed. The lensing amplification for the sources is
in the range 1.5-7, assuming that they lie at z>1. The brightest detected X-ray
source has a faint extended optical counterpart (I~22) with colours consistent
with a galaxy at z~1. The X-ray spectrum of this galaxy is hard, implying
strong intrinsic absorption with a column density of about 1e23 cm-2 and an
intrinsic (unabsorbed) 2-10 keV luminosity of 3e44 erg/s. This source is
therefore a Type-II quasar. The weakest detected X-ray sources are not detected
in HST images down to I~26.

</DOC>
<DOC>
<DOCNO> 119305 </DOCNO>
EUVE Observations of Hercules X-1 During a Short High State Turn-On


  Observations of Hercules X-1 by the Extreme Ultraviolet Explorer (EUVE)
covering low state and the early part of the Short High state are reported
here. This is the first EUV observation of this part of the 35-day cycle of Her
X-1. The low state portion of the EUV light curve (prior to the start of the
Short High state) has similar properties as that following the end of the Short
High state (Leahy and Marshall, 1999). This is evidence that the low state EUV
emission is primarily due to EUV reflection from the companion star HZ Her. The
EUV lightcurve during the Short High state is pulsed and closely resembles the
average 2-12 keV X-ray Short High state lightcurve indicating that the EUV
emission, like the X-ray emission, originates near the neutron star. The Short
High state EUV spectrum is consistent with a blackbody of temperature 0.13 keV
and radius 230 km. The Short High state EUV spectrum and pulse shape are
similar to that in the soft X-rays (0.1 - 1 keV). The most likely origin of the
EUV emission is reprocessed X-rays from the inner edge of the accretion disk,
and the radius of the inner edge of the accretion disk is likely to be small,
consistent with that determined from analysis of the X-ray pulse shape
evolution (Scott, Leahy and Wilson, 2000).

</DOC>
<DOC>
<DOCNO> 150339 </DOCNO>
Once again on the equivalence theorem


  We present the proof of the equivalence theorem in quantum field theory which
is based on a formulation of this problem in the field-antifield formalism. As
an example, we consider a model in which a different choices of natural finite
counterterms is possible, leading to physically non-equivalent quantum theories
while the equivalent theorem remains valid.

</DOC>
<DOC>
<DOCNO> 68104 </DOCNO>
The $F/D$ ratio and meson-baryon couplings from QCD sum rules-II


  Using QCD sum rules, we compute the diagonal meson-baryon couplings, $\pi
NN$, $\eta NN$, $\pi \Xi\Xi$, $\eta \Xi\Xi$, $\pi \Sigma \Sigma$ and $\eta
\Sigma \Sigma$, from the baryon-baryon correlation function with a meson,
$i\int d^4x e^{iq\cdot x} < 0| T J_B(x) {\bar J}_B(0)|M(p)>$. The calculations
are performed to leading order in $p_\mu$ by considering the two separate Dirac
structures, $i \gamma_5 \gamma_\mu p^\mu$ and $\gamma_5 \sigma_{\mu \nu} {q^\mu
p^\nu}$ separately. We first improve the previous sum rule calculations on
these Dirac structures for the $\pi NN$ coupling by including three-particle
pion wave functions of twist 4 and then extend the formalism to calculate the
other couplings, $\eta NN$, $\pi \Xi\Xi$, $\eta \Xi\Xi$, $\pi \Sigma \Sigma$
and $\eta \Sigma \Sigma$. In the SU(3) symmetric limit, we identify the terms
responsible for the $F/D$ ratio in the OPE by matching the obtained couplings
with their SU(3) relations. Depending on the Dirac structure considered, we
find different identifications for the $F/D$ ratio. The couplings including the
SU(3) breaking effects are also discussed within our approach.

</DOC>
<DOC>
<DOCNO> 84847 </DOCNO>
Black Hole Entropy in 1+1 Dimensions from a Quasi-Chern Simons term in a


  We introduce a 'quasi-topological` term [1] in D=1+1 dimensions and the
entropy for black holes is calculated [2]. The source of entropy in this case
is justified by a non-null stress-energy tensor.

</DOC>
<DOC>
<DOCNO> 71395 </DOCNO>
Galaxy-QSO Correlation induced by Weak Gravitational Lensing arising


  Observational evidence shows that gravitational lensing induces an angular
correlation between the distribution of galaxies and much more distant QSOs. We
use weak gravitational lensing theory to calculate this angular correlation,
updating previous calculations and presenting new results exploring the
dependence of the correlation on the large-scale structure. We study the
dependence of the predictions on a variety of cosmological models, such as cold
dark matter models, mixed dark matter models, and models based on quintessence.
We also study the dependence on the assumptions made about the nature of the
primordial fluctuation spectrum: adiabatic, isocurvature and power spectra
motivated by the cosmic string scenario are investigated. Special attention is
paid to the issue of galaxy biasing, which is fully incorporated. We show that
different mass power spectra imply distinct predictions for the angular
correlation, and therefore the angular correlation provides an extra source of
information about cosmological parameters and mechanisms of structure
formation. We compare our results with observational data and discuss their
potential uses. In particular, it is suggested that the observational
determination of the galaxy-QSO correlation may be used to give an independent
measurement of the mass power spectrum.

</DOC>
<DOC>
<DOCNO> 8741 </DOCNO>
Nuclear Multifragmentation in the Non-extensive Statistics - Canonical


  We apply the canonical quantum statistical model of nuclear
multifragmentation generalized in the framework of recently proposed Tsallis
non-extensive thermostatistics for the description of nuclear
multifragmentation process. The test calculation in the system with A=197
nucleons show strong modification of the 'critical' behaviour associated with
the nuclear liquid-gas phase transition for small deviations from the
conventional Boltzmann-Gibbs statistical mechanics.

</DOC>
<DOC>
<DOCNO> 71463 </DOCNO>
Extracting energies from the vacuum


  We present and study a possible mechanism of extracting energies from the
vacuum by external classical fields. Taking a constant magnetic field as an
example, we discuss why and how the vacuum energy can be released in the
context of quantum field theories. In addition, we give a theoretical
computation showing how much vacuum energies can be released. The possibilities
of experimentally detecting such a vacuum-energy releasing are discussed.

</DOC>
<DOC>
<DOCNO> 12334 </DOCNO>
Universal amplitude ratios in finite-size scaling: three-dimensional


  Motivated by the results of two-dimensional conformal field theory (CFT) we
investigate the finite-size scaling of the mass spectrum of an Ising model on
three-dimensional lattices with a spherical cross section. Using a
cluster-update Monte Carlo technique we find a linear relation between the
masses and the corresponding scaling dimensions, in complete analogy to the
situation in two dimensions. Amplitude ratios as well as the amplitudes
themselves appear to be universal in this case.

</DOC>
<DOC>
<DOCNO> 123316 </DOCNO>
On the source of QPO of the black hole candidate GRS1915+105: some new


  A few classes of the light curve of the black hole candidate GRS 1915+105
have been analyzed in detail. We discover that unlike the previous findings,
QPOs occasionally occur even in the so-called `On' or softer states. Such
findings may require a revision of the accretion/wind scenario of the black
hole candidates. We conjecture that considerable winds which is produced in
`Off' states, cool down due to Comptonization, and falls back to the disk and
creating an excess accretion rate to produce the so-called `On' state. After
the drainage of the excess matter, the disk goes back to the `Off' state. Our
findings strengthen the shock oscillation model for QPOs.

</DOC>
<DOC>
<DOCNO> 170651 </DOCNO>
Quantum Cloning and Distributed Measurements


  We study measurements on various subsystems of the output of a universal 1 to
2 cloning machine, and establish a correspondence between these measurements at
the output and effective measurements on the original input. We show that one
can implement sharp effective measurement elements by measuring only two out of
the three output systems. Additionally, certain complete sets of sharp
measurements on the input can be realised by measurements on the two clones.
Furthermore, we introduce a scheme that allows to restore the original input in
one of the output bits, by using measurements and classical communication -- a
protocol that resembles teleportation.

</DOC>
<DOC>
<DOCNO> 122821 </DOCNO>
A Progress Report on the Caltech Faint Galaxy Redshift Survey


  I review recent progress on determining the spectral energy distributions and
luminosity functions for galaxies in the large magnitude limited sample in the
region of the HDF-North of the Caltech Faint Galaxy Redshift Survey.

</DOC>
<DOC>
<DOCNO> 121471 </DOCNO>
X-ray iron line variability: constraints on the inner accretion disk


  After reviewing the basic physics of X-ray reflection in AGN, we present
three case studies which illustrate the current state of X-ray reflection
studies. For the low-luminosity AGN NGC4258, we find that the iron line is much
narrower than is typically found in higher luminosity AGN. We argue that this
is evidence for either a truncated cold accretion disk (possibly due to a
transition to an advection dominate accretion flow at r ~ 100GM/c^2) or a large
r ~ 100GM/c^2 X-ray emitting corona surrounding the accretion disk. We also
present results for the higher luminosity Seyfert nuclei in NGC5548 and
MCG-6-30-15. In both of these sources, RXTE shows that the iron line equivalent
width decreases with increasing luminosity. Furthermore, the iron line
equivalent width is found to be anticorrelated with the relative strength of
the reflection continuum, contrary to all simple reflection models. It is
proposed that continuum-flux correlated changes in the ionization of the
accretion disk surface can explain this spectral variability. Finally, we
address the issue of X-ray iron line reverberation in the light of these
complicating factors.

</DOC>
<DOC>
<DOCNO> 11677 </DOCNO>
Comment on "Low Temperature Magnetic Instabilities in Triply Charged


  Recently, Arcon et al. reported ESR studies of the polymer phase (PP) of
Na_{2}Rb_{0.3}Cs_{0.7}C_{60} fulleride. It was claimed that this phase is a
quasi-one-dimensional metal above 45 K with a spin-gap below this temperature
and has antiferromagnetic(AF) order below 15 K, that is evidenced by
antiferromagnetic resonance(AFMR). For the understanding of the rich physics of
fullerides it is important to identify the different ground states. ESR has
proven to be a useful technique for this purpose. However, since it is a very
sensitive probe, it can detect a multitude of spin species and it is not
straightforward to identify their origin, especially in a system like
Na_{2}Rb_{x}Cs_{1-x}C_{60} with three dopants, when one part of the sample
polymerizes but the majority does not. The observation of a low dimensional
instability in the single bonded PP would be a novel and important result.
Nevertheless, in this Comment we argue that Na_{2}Rb_{0.3}Cs_{0.7}C_{60} is not
a good choice for this purpose since, as we show, the samples used by Arcon et
al. are inhomogeneous. We point out that recent results on the PP of
Na_{2}CsC_{60} contradicts the observation of low dimensional instabilities in
Na_{2}Rb_{0.3}Cs_{0.7}C_{60}.

</DOC>
<DOC>
<DOCNO> 117131 </DOCNO>
Atomic effects in astrophysical nuclear reactions


  Two models are presented for the description of the electron screening
effects that appear in laboratory nuclear reactions at astrophysical energies.
The two-electron screening energy of the first model agrees very well with the
recent LUNA experimental result for the break-up reaction $%
He3(He3,2p)He^{4}$, which so far defies all available theoretical models.
Moreover, multi-electron effects that enhance laboratory reactions of the CNO
cycle and other advanced nuclear burning stages, are also studied by means of
the Thomas-Fermi model, deriving analytical formulae that establish a lower and
upper limit for the associated screening energy. The results of the second
model, which show a very satisfactory compatibility with the adiabatic
approximation ones, are expected to be particularly useful in future
experiments for a more accurate determination of the CNO astrophysical factors.

</DOC>
<DOC>
<DOCNO> 68838 </DOCNO>
Visualizations of the QCD Vacuum


  Action and topological charge densities of the Euclidean-space QCD vacuum are
visualized in three-dimensional slices of a 24^3 x 36 space-time lattice and an
order-a^2 improved 16^3 x 32 lattice. Features include instanton anti-instanton
annihilation and a comparison of standard and over-improved actions used in the
smoothing of the gauge fields.

</DOC>
<DOC>
<DOCNO> 68275 </DOCNO>
Improved determination of b quark mass from spectroscopy


  Using recently evaluated contributions (including a novel one calculated
here), we present updated values for the pole mass and $\bar{MS}$ mass of the
$b$ quark: $m_b=5022\pm58$ MeV, for the pole mass, and
$\bar{m}_b(\bar{m}_b)=4286\pm36$ MeV for the $\bar{MS}$ one. These values are
accurate including, respectively,
  $O(\alpha_s^5\log\alpha_s)$ and $O(\alpha_s^3)$ corrections and, in both
cases, leading orders in the ratio $m_c^2/m_b^2$.

</DOC>
<DOC>
<DOCNO> 121563 </DOCNO>
Damped Lyman-Alpha Galaxies


  Some results from an imaging program to identify low-redshift (0.09<z<1.63)
damped Lyman-alpha (DLA) galaxies are presented. The standard paradigm that was
widely accepted a decade ago, that DLA galaxies are the progenitors of luminous
disk galaxies, is now being seriously challenged. The indisputable conclusion
from imaging studies at low redshift is that the morphological types of DLA
galaxies are mixed and that they span a range in luminosities and surface
brightnesses.

</DOC>
<DOC>
<DOCNO> 80631 </DOCNO>
Absence of Asymptotic Freedom in Non-Abelian Models


  The percolation properties of equatorial strips of the two dimensional O(3)
nonlinear $\sigma$ model are investigated numerically. Convincing evidence is
found that a sufficently narrow strip does not percolate at arbitrarily low
temperatures. Rigorous arguments are used to show that this result implies both
the presence of a massless phase at low temperature and lack of asymptotic
freedom in the massive continuum limit. A heuristic estimate of the transition
temperature is given which is consistent with the numerical data.

</DOC>
<DOC>
<DOCNO> 117748 </DOCNO>
Prompt Optical Observations of Gamma-ray Bursts


  The Robotic Optical Transient Search Experiment (ROTSE) seeks to measure
simultaneous and early afterglow optical emission from gamma-ray bursts (GRBs).
A search for optical counterparts to six GRBs with localization errors of 1
square degree or better produced no detections. The earliest limiting
sensitivity is m(ROTSE) > 13.1 at 10.85 seconds (5 second exposure) after the
gamma-ray rise, and the best limit is m(ROTSE) > 16.0 at 62 minutes (897 second
exposure). These are the most stringent limits obtained for GRB optical
counterpart brightness in the first hour after the burst. Consideration of the
gamma-ray fluence and peak flux for these bursts and for GRB990123 indicates
that there is not a strong positive correlation between optical flux and
gamma-ray emission.

</DOC>
<DOC>
<DOCNO> 120181 </DOCNO>
The Dependence of the Galaxy Luminosity Function on Environment


  We present luminosity functions for galaxies in loose groups in the Las
Campanas Redshift Survey, differentiated by their environment (defined by the
line-of-sight velocity dispersion sigma of the host groups) and also by their
spectral type (emission or non-emission, defined by the equivalent width of the
3727-Angstrom [OII] line).
 We find systematic variations in the Schechter parameters alpha and M* for
non-emission line galaxies over a range of 0 < sigma < 800 km/s. Alpha varies
from 0.20 to -0.91, indicating an increase in the steepness of the faint end
slope with increasing sigma. The accompanying variation in M* appears to be
accounted for by the intrinsic correlation with alpha and does not indicate a
significant physical variation in the bright end of the luminosity function.
For emission line galaxies, we find no significant systematic variation of the
luminosity function with the environment. Our results show that emission and
non-emission galaxies generally occupy two distinct regions in the alpha-M*
parameter space. From our luminosity functions, we derive the number ratios of
emission to non-emission galaxies as a function of environment and absolute
magnitude, showing that the relative abundance of non-emission line galaxies
generally increases for all magnitudes -23 < M_R < -17.5 towards high-sigma
environments, from ~80% to >90% at M_R = -22 and from ~10% to >50% at M_R = -18
(H_0 = 100 km s^{-1} Mpc^{-1} and q_0 = 0.5).

</DOC>
<DOC>
<DOCNO> 117635 </DOCNO>
Constraining SN Ia Models Using X-ray Spectra of Clusters of Galaxies


  We present constraints on theoretical models of Type Ia SNe using spatially
resolved ASCA X-ray spectroscopy of four galaxy clusters: Abell 496, Abell
2199, Abell 3571 & Perseus. All four clusters have central Fe abundance
enhancements and an ensemble of abundance ratios are used to show that most of
the Fe in the central regions of the clusters comes from SN Ia. At the center
of each cluster, simultaneous analysis of spectra from all ASCA instruments
shows that the Ni to Fe abundance ratio (normalized by the solar ratio) is ~ 4.
We use the Ni/Fe ratio as a discriminator between SN Ia explosion models: the
Ni/Fe ratio of ejecta from the "Convective Deflagration" model W7 is consistent
with the observations, while those of "delayed detonation" models are not
consistent at the 90% confidence level.

</DOC>
<DOC>
<DOCNO> 9137 </DOCNO>
Enhanced Pinning of Vortices in Thin Film Superconductors by Magnetic


  We study the pinning of vortices in thin film superconductors by magnetic
dots in the London approximation. A single dot is in general able to pin
multiple field-induced vortices, up to a saturation number n_s, which can be
much larger than one. However, the magnetic field of the dot also creates
intrinsic vortices and anti-vortices, which must be accounted for. In a
ferromagnetic dot array, the intrinsic anti-vortices are pinned only
interstitially. Much stronger pinning effect is expected of an
antiferromagnetic dot array. Possible realizations of various magnetic
configurations are discussed.

</DOC>
<DOC>
<DOCNO> 120463 </DOCNO>
Study of FK Comae Berenices. II. Spot evolution from 1994 to 1997


  We present new surface (Doppler) images of the late-type single giant FK Com
for June-July 1996, July-August 1996, April 1997 and June 1997. These images
are compared with the previously published images from 1994 and 1995. The
consecutive maps are cross-correlated to see the possible migration of the
spots and the effects of differential rotation. The cross-correlation confirms
an average longitudinal spot migration of 0.22+/-0.03 in phase within a year.
This movement is probably an artifact caused by a difference between the
accepted rotation period and the real photometric period for these years. If
this is true, then the photometric rotation period for these years is
2.4037+/-0.0005 days. Measurements from these four years and six maps limit the
surface differential rotation to alpha=0.0001+/-0.0002, where alpha is the
difference between polar and equatorial angular velocities relative to the
equatorial angular velocity.

</DOC>
<DOC>
<DOCNO> 123317 </DOCNO>
Relation of Light Curve Behaviour with Accretion Rates in Black Hole


  We report some properties of the light curves of GRS 1915+105 and present
their interpretation using the variation of net accretion rate.

</DOC>
<DOC>
<DOCNO> 9220 </DOCNO>
Anomalous field-dependent specific heat in charge-ordered


  We report low temperature specific heat measurements of
Pr$_{1-x}$Ca$_{x}$MnO$_{3}$ ($0.3\leq x \leq 0.5$) and
La$_{0.5}$Ca$_{0.5}$MnO$_{3}$ with and without applied magnetic field. An
excess specific heat, $C^{\prime}(T)$, of non-magnetic origin associated with
charge ordering is found for all the samples. A magnetic field sufficient to
induce the transition from the charge-ordered state to the ferromagnetic
metallic state does not completely remove the $C^{\prime}$ contribution. This
suggests that the charge ordering is not completely destroyed by a "melting"
magnetic field. In addition, the specific heat of the
Pr$_{1-x}$Ca$_{x}$MnO$_{3}$ compounds exhibit a large contribution linear in
temperature ($\gamma T$) originating from magnetic and charge disorder.

</DOC>
<DOC>
<DOCNO> 152283 </DOCNO>
Unstable Non-BPS D-Branes of Type-II String Theories in Light-Cone


  The problem of describing the boundary states of unstable non-BPS D-branes of
type-II string theories in light-cone Green-Schwarz (GS) formalism is
addressed. Regarding the type II theories in light-cone gauge as different
realizations of the $\hat{SO}(8)_{k=1}$ Kac-Moody algebra, the non-BPS D-brane
boundary states of these theories are given in terms of the relevant Ishibashi
states constructed in this current algebra. Using the expressions for the
current modes in terms of the GS variables it is straightforward to reexress
the boundary states in the GS formalism. The problem that remains is the lack
of manifest SO(8) covariance in these expressions. We also derive the various
known expressions for the BPS and non-BPS D-brane boundary states by starting
with the current algebra Ishibashi states.

</DOC>
<DOC>
<DOCNO> 72116 </DOCNO>
Instanton-Meron Hybrid in the Background of Gravitational Instantons


  When it comes to the topological aspects, gravity may have profound effects
even at the level of particle physics despite its negligibly small relative
strength well below the Planck scale. In spite of this intriguing possibility,
relatively little attempt has been made toward the exhibition of this
phenomenon in relevant physical systems. In the present work, perhaps the
simplest and the most straightforward new algorithm for generating solutions to
(anti) self-dual Yang-Mills (YM) equation in the typical gravitational
instanton backgrounds is proposed and then applied to find the solutions
practically in all the gravitational instantons known. Solutions thus obtained
turn out to be some kind of instanton-meron hybrids possessing mixed features
of both. Namely, they are rather exotic type of configurations obeying first
order (anti) self-dual YM equation which are everywhere non-singular and have
finite Euclidean YM actions on one hand while exhibiting meron-like large
distance behavior and carrying generally fractional topological charge values
on the other. Close inspection, however, reveals that the solutions are more
like instantons rather than merons in their generic natures.

</DOC>
<DOC>
<DOCNO> 118551 </DOCNO>
A Prediction of Observable Rotation in the ICM of Abell 3266


  We present a numerical Hydro+N-body model of A3266 whose X-ray surface
brightness, temperature distribution, and galaxy spatial and velocity
distribution data are consistent with the A3266 data. The model is an old (~3
Gyr), off-axis merger having a mass ratio of ~2.5:1. The less massive
subcluster in the model is moving on a trajectory from southwest to northeast
passing on the western side of the dominant cluster while moving into the plane
of the sky at ~45 degrees. Off-axis mergers such as this one are an effective
mechanism for transferring angular momentum to the intracluster medium (ICM),
making possible a large scale rotation of the ICM. We demonstrate here that the
ICM rotation predicted by our fully 3-dimensional model of A3266 is observable
with current technology. As an example, we present simulated observations
assuming the capabilities of the high resolution X-ray spectrometer (XRS) which
was to have flown on Astro-E.

</DOC>
<DOC>
<DOCNO> 8916 </DOCNO>
Low temperature vortex phase diagram of Bi2Sr2CaCu2O8 : a magnetic


  We report measurements of the magnetic penetration depth \lambda_m(T) in the
presence of a DC magnetic field in optimally doped BSCCO-2212 single crystals.
Warming, after magnetic field is applied to a zero-field cooled sample, results
in a non-monotonic \lambda_m(T), which does not coincide with a curve obtained
upon field cooling, thus exhibiting a hysteretic behaviour. We discuss the
possible relation of our results to the vortex decoupling, unbinding, and
dimensional crossover.

</DOC>
<DOC>
<DOCNO> 7652 </DOCNO>
Similarity Solutions and Collapse in the Attractive Gross-Pitaevskii


  We analyse a generalised Gross-Pitaevskii equation involving a paraboloidal
trap potential in $D$ space dimensions and generalised to a nonlinearity of
order $2n+1$. For {\em attractive} coupling constants collapse of the particle
density occurs for $Dn\ge 2$ and typically to a $\delta$-function centered at
the origin of the trap. By introducing a new dynamical variable for the
spherically symmetric solutions we show that all such solutions are
self-similar close to the center of the trap. Exact self-similar solutions
occur if, and only if, $Dn=2$, and for this case of $Dn=2$ we exhibit an exact
but rather special D=1 analytical self-similar solution collapsing to a
$\delta$-function which however recovers and collapses periodically, while the
ordinary G-P equation in 2 space dimensions also has a special solution with
periodic $\delta$-function collapses and revivals of the density. The relevance
of these various results to attractive Bose-Einstein condensation in
spherically symmetric traps is discussed.

</DOC>
<DOC>
<DOCNO> 9271 </DOCNO>
Axial phase of quantum fluids in nanotubes


  We explore the equations of state and other properties of various quantum
fluids (3He, 4He, their mixtures, and H_2) confined within individual carbon
nanotubes. Above a threshold number of particles, N_a, the fluid density near
the axis begins to grow above a negligibly small value. The properties of this
axial fluid phase are sensitive to the tube size and hence to the transverse
compression in the case of a bundle of nanotubes. We consider He at zero
temperature and H_2 at low temperatures.

</DOC>
<DOC>
<DOCNO> 84357 </DOCNO>
On product spacetime with 2-sphere of constant curvature


  If we consider the spacetime manifold as product of a constant curvature
2-sphere (hypersphere) and a 2-space, then solution of the Einstein equation
requires that the latter must also be of constant curvature. There exist only
two solutions for classical matter distribution which are given by the Nariai
(anti) metric describing an Einstein space and the Bertotti - Robinson (anti)
metric describing a uniform electric field. These two solutions are
transformable into each other by letting the timelike convergence density
change sign. The hyperspherical solution is anti of the spherical one and the
vice -versa. For non classical matter, we however find a new solution, which is
electrograv dual to the flat space, and describes a cloud of string dust of
uniform energy density. We also discuss some interesting features of the
particle motion in the Bertotti - Robinson metric.

</DOC>
<DOC>
<DOCNO> 12691 </DOCNO>
Experimental tests for the relevance of two-level systems for electron


  The relevance of tunneling two-level systems (TLS) for electron dephasing in
metals is analyzed. We demonstrate that if the concentration of TLS is
sufficient to cause the observed dephasing rate, one also should expect quite
substantial effects in the specific heat and ultrasound attenuation. In both
cases TLS contribution should dominate the electronic one at low enough
temperatures.

</DOC>
<DOC>
<DOCNO> 102405 </DOCNO>
Critical two-point functions and the lace expansion for spread-out


  We consider spread-out models of self-avoiding walk, bond percolation,
lattice trees and bond lattice animals on the d-dimensional hyper cubic lattice
having long finite-range connections, above their upper critical dimensions d=4
(self-avoiding walk), d=6 (percolation) and d=8 (trees and animals). The
two-point functions for these models are respectively the generating function
for self-avoiding walks from the origin to x, the probability of a connection
from 0 to x, and the generating function for lattice trees or lattice animals
containing 0 and x. We use the lace expansion to prove that for sufficiently
spread-out models above the upper critical dimension, the two-point function of
each model decays, at the critical point, as a multiple of $|x|^{2-d}$ as x
goes to infinity. We use a new unified method to prove convergence of the lace
expansion. The method is based on x-space methods rather than the Fourier
transform. Our results also yield unified and simplified proofs of the bubble
condition for self-avoiding walk, the triangle condition for percolation, and
the square condition for lattice trees and lattice animals, for sufficiently
spread-out models above the upper critical dimension.

</DOC>
<DOC>
<DOCNO> 72001 </DOCNO>
Hadron production in nuclear collisions at RHIC and high density QCD


  We analyze the first results on charged particle multiplicity at RHIC in the
conventional eikonal approach and in the framework of high density QCD. We
extract the fraction $F$ of the hadron multiplicity originating from ``hard''
(i.e. proportional to the number of binary collisions) processes; we find a
strong growth of this fraction with energy: $F(\sqrt{s}=56 {\rm GeV}) \simeq
22%$, while $F(\sqrt{s}=130 {\rm GeV}) \simeq 37 %$. This indicates a rapid
increase in the density of the produced particles. We outline the predictions
of high density QCD for the centrality, energy, and atomic number dependence of
hadron production. Surprisingly, the predictions of the conventional eikonal
approach and of high density QCD for centrality dependence of hadron
multiplicity at $\sqrt{s}=130 {\rm GeV}$ appear very similar.

</DOC>
<DOC>
<DOCNO> 9276 </DOCNO>
Magnetoresistance of a two-dimensional electron gas in a parallel


  The conductivity of a two-dimensional electron gas in a parallel magnetic
field is calculated. We take into account the magnetic field induced
spin-splitting, which changes the density of states, the Fermi momentum and the
screening behavior of the electron gas. For impurity scattering we predict a
positive magnetoresistance for low electron density and a negative
magnetoresistance for high electron density. The theory is in qualitative
agreement with recent experimental results found for Si inversion layers and Si
quantum wells.

</DOC>
<DOC>
<DOCNO> 10830 </DOCNO>
Fractionalization and confinement in the U(1) and $Z_2$ gauge theories


  Recently, we have elucidated the physics of electron fractionalization in
strongly interacting electron systems using a $Z_2$ gauge theory formulation.
Here we discuss the connection with the earlier U(1) gauge theory approaches
based on the slave boson mean field theory. In particular, we identify the
relationship between the holons and Spinons of the slave-boson theory and the
true physical excitations of the fractionalized phases that are readily
described in the $Z_2$ approach.

</DOC>
<DOC>
<DOCNO> 122634 </DOCNO>
UV observations of the galaxy cluster Abell 1795 with the optical


  We present the results of an analysis of broad band UV observations of the
central regions of Abell 1795 observed with the optical monitor on XMM-Newton.
As have been found with other UV observations of the central regions of
clusters of galaxies, we find evidence for star formation. However, we also
find evidence for absorption in the cD galaxy on a more extended scale than has
been seen with optical imaging. We also report the first UV observation of part
of the filamentary structure seen in H$\alpha$, X-rays and very deep U band
imaging. The part of the filament we see is very blue with UV colours
consistent with a very early (O/B) stellar population. This is the first direct
evidence of a dominant population of early type stars at the centre of Abell
1795 and implies very recent star formation at the centre of this cluster

</DOC>
<DOC>
<DOCNO> 14020 </DOCNO>
Remark on the Second Principle of Thermodynamics


  All presently available results lead to the conclusion that nonextensivity,
in the sense of nonextensive statistical mechanics (i.e., $q \ne 1$), does {\it
not} modify anything to the second principle of thermodynamics, which therefore
holds in the usual way. Moreover, some claims in the literature that this
principle can be violated for specific anomalous systems (e.g., granular
materials) can be shown to be fallacious. One recent such example is analyzed,
and it is suggested how $q \ne 1$ distributions could in fact restore the
validity of macroscopic time irreversibility, a cornerstone of our present
understanding of nature.

</DOC>
<DOC>
<DOCNO> 102544 </DOCNO>
Proper actions of lattices on contractible manifolds


  Every lattice H in a connected semi-simple Lie group G acts properly
discontinuously by isometries on the contractible manifold G/K (K a maximal
compact subgroup of G). We prove that if H acts on a contractible manifold W
and if either
  1) the action is properly discontinuous, or
  2) W is equipped with a complete Riemannian metric, the action is by
isometries and with unbounded orbits, G is simple with finite center and rank
>1, then dim W is not less than dim G/K.

</DOC>
<DOC>
<DOCNO> 123142 </DOCNO>
Shocked Molecular Gas in the Supernova Remnant HB 21


  We report the discovery of the shocked molecular gas in the supernova remnant
HB 21. We derive the physical parameters of the shocked gas from CO J=1-0 and
J=2-1 line observations. We discuss the correlation of the shocked molecular
gas with the previously detected, shocked atomic gas and the associated
infrared emission.

</DOC>
<DOC>
<DOCNO> 122076 </DOCNO>
Magnetic Fields in Young Galaxies


  We have studied the fate of initial magnetic fields in the hot halo gas out
of which the visible parts of galaxies form, using three-dimensional numerical
MHD-experiments. The halo gas undergoes compression by several orders of
magnitude in the subsonic cooling flow that forms the cold disk. The magnetic
field is carried along and is amplified considerably in the process, reaching
muG levels for reasonable values of the initial ratio of magnetic to thermal
energy density.

</DOC>
<DOC>
<DOCNO> 116362 </DOCNO>
Coherent and incoherent atomic scattering: Formalism and application to


  The experimental determination of the lifetime of pionium provides a very
important test on chiral perturbation theory. This quantity is determined in
the DIRAC experiment at CERN. In the analysis of this experiment, the breakup
probabilities of of pionium in matter are needed to high accuracy as a
theoretical input. We study in detail the influence of the target electrons.
They contribute through screening and incoherent effects. We use Dirac-Hartree-
Fock-Slater wavefunctions in order to determine the corresponding form factors.
We find that the inner-shell electrons contribute less than the weakly bound
outer electrons. Furthermore, we establish a more rigorous estimate for the
magnitude of the contributions form the transverse current (magnetic terms thus
far neglected in the calculations).

</DOC>
<DOC>
<DOCNO> 116568 </DOCNO>
Multi frequency evaporative cooling to BEC in a high magnetic field


  We demonstrate a way to circumvent the interruption of evaporative cooling
observed at high bias field for $^{87}$Rb atoms trapped in the (F=2, m=+2)
ground state. Our scheme uses a 3-frequencies-RF-knife achieved by mixing two
RF frequencies. This compensates part of the non linearity of the Zeeman
effect, allowing us to achieve BEC where standard 1-frequency-RF-knife
evaporation method did not work. We are able to get efficient evaporative
cooling, provided that the residual detuning between the transition and the RF
frequencies in our scheme is smaller than the power broadening of the RF
transitions at the end of the evaporation ramp.

</DOC>
<DOC>
<DOCNO> 152013 </DOCNO>
Unified Study of Planar Field Theories


  A "Master" gauge theory is constructed in 2+1-dimensions through which
various gauge invariant and gauge non-invariant theories can be studied. In
particular, Maxwell-Chern-Simons, Maxwell-Proca and Maxwell-Chern-Simons -Proca
models are considered here. The Master theory in an enlarged phase space is
constructed both in Lagrangian (Stuckelberg) and Hamiltonian (Batalin-Tyutin)
frameworks, the latter being the more general one, which includes the former as
a special case. Subsequently, BRST quantization of the latter is performed.
Lastly, the master Lagrangian, constructed by Deser and Jackiw (Phys. Lett.
B139, (1984) 371), to show the equivalence between the Maxwell-Chern-Simons and
the self-dual model, is also reproduced from our Batalin-Tyutin extended model.
Symplectic quantization procedure for constraint systems is adopted in the last
demonstration.

</DOC>
<DOC>
<DOCNO> 11372 </DOCNO>
Enumerations of lattice animals and trees


  We have developed an improved algorithm that allows us to enumerate the
number of site animals on the square lattice up to size 46. We also calculate
the number of lattice trees up to size 44 and the radius of gyration of both
lattice animals and trees up to size 42. Analysis of the resulting series
yields an improved estimate, $\lambda = 4.062570(8)$, for the growth constant
of lattice animals, and, $\lambda_0 = 3.795254(8)$, for the growth constant of
trees, and confirms to a very high degree of certainty that both the animal and
tree generating functions have a logarithmic divergence. Analysis of the radius
of gyration series yields the estimate, $\nu = 0.64115(5)$, for the size
exponent.

</DOC>
<DOC>
<DOCNO> 68550 </DOCNO>
A consistent interpretation of the Karmen anomaly


  The Karmen anomaly can be interpreted as being due to a heavy neutrino of
mass around 137 MeV produced in $\pi_{e 2}$ decays. This interpretation is
consistent with the present limits on the couplings of such an object.

</DOC>
<DOC>
<DOCNO> 71382 </DOCNO>
$\mu$ Problem, SO(10) SUSY GUT and Heavy Gluino LSP


  We present a solution to the $\mu$ problem in an SO(10) supersymmetric grand
unified (SUSY GUT) model with gauge mediated (GMSB) and D-term supersymmetry
breaking. A Peccei-Quinn ({\bf PQ}) symmetry is broken at the messenger scale
and enables the generation of the $\mu$ term. The invisible axion (Goldstone
boson of {\bf PQ} symmetry breaking) is a cold dark matter candidate. At low
energy, our model leads to a phenomenologically acceptable version of the
minimal supersymmetric standard model (MSSM) with novel particle phenomenology.
Either the gluino or the gravitino is the lightest supersymmetric particle
(LSP). The phenomenological constraints on the model result in a Higgs with
mass $\sim 86 - 91$ GeV and $\tan\beta \sim 9 - 14$.

</DOC>
<DOC>
<DOCNO> 102216 </DOCNO>
Natural Energy Bounds in Quantum Thermodynamics


  Given a stationary state for a noncommutative flow, we study a boundedness
condition, depending on a positive parameter beta, which is weaker than the KMS
equilibrium condition at inverse temperature beta. This condition is equivalent
to a holomorphic property closely related to the one recently considered by
Ruelle and D'Antoni-Zsido and shared by a natural class of non-equilibrium
steady states. Our holomorphic property is stronger than the Ruelle's one and
thus selects a restricted class of non-equilibrium steady states. We also
introduce the complete boundedness condition and show this notion to be
equivalent to the Pusz-Woronowicz complete passivity property, hence to the KMS
condition.
  In Quantum Field Theory, the beta-boundedness condition can be interpreted as
the property that localized state vectors have energy density levels increasing
beta-subexponentially, a property which is similar in the form and weaker in
the spirit than the modular compactness-nuclearity condition. In particular,
for a Poincare' covariant net of C*-algebras on the Minkowski spacetime, the
beta-boundedness property, for beta greater equal than 2 pi, for the boosts is
shown to be equivalent to the Bisognano-Wichmann property. The Hawking
temperature is thus minimal for a thermodynamical system in the background of a
Rindler black hole within the class of beta-holomorphic states. More generally,
concerning the Killing evolution associated with a class of stationary quantum
black holes, we characterize KMS thermal equilibrium states at Hawking
temperature in terms of the boundedness property and the existence of a
translation symmetry on the horizon.

</DOC>
<DOC>
<DOCNO> 152270 </DOCNO>
Matrix Model and String Field Theory


  In this short note we would like to show the relation between the cubic
string field theory for N D-instantons and the string field theory in the
presence of the background B field.

</DOC>
<DOC>
<DOCNO> 118719 </DOCNO>
The excitation and kinematical properties of H2 and [FeII] in the


  Long slit spectra of the molecular outflow Herbig-Haro (HH) 46/47 has been
taken in the J and K near-infrared bands. The observed H2 line emission
confirms the existence of a bright and extended redshifted counter-jet outflow
southwest of HH46. We show that this outflow seems to be composed of two
different emission regions which have distinct heliocentric velocities, in
contrast with the optical appearance, and which implies an acceleration of the
counter-jet. The observed [FeII] emission suggests an average extinction of 7-9
visual magnitudes for the region associated with the counter-jet. Through
position-velocity diagrams, we show the existence of different morphologies for
the H2 and [FeII] emission regions in the northern part of the HH46/47 outflow.
We have detected for the first time high velocity (-250 Km/s) [FeII] emission
in the region bridging HH46 to HH47A. The two strong peaks detected can be
identified with the optical positions B8 and HH47B. The H2 excitation diagrams
for the counter-jet shock suggest an excitation temperature for the gas of Tex
approx. 2600K. The lack of emission from the higher energy H2 lines such as the
4-3S(3) transition, suggests a thermal excitation scenario for the origin of
the observed emission. Comparison of the H2 line ratios to various shock models
yielded useful constraints about the geometry and type of these shocks. Planar
shocks can be ruled out whereas curved or bow-shocks (both J and C-type) can be
parametrised to adjust our data.

</DOC>
<DOC>
<DOCNO> 71034 </DOCNO>
Inclusive Direct Photon and Pion Production in Proton Nucleon Collisions


  We present a study of inclusive direct-photon and neutral pion production in
hadronic interactions that focuses on a comparison of the ratio of photon and
pion yields with expectations from next-to-leading order perturbative QCD (NLO
pQCD).

</DOC>
<DOC>
<DOCNO> 121462 </DOCNO>
The bright 175um knots of the Andromeda Galaxy


  Discrete far-infrared (FIR) sources of M31 are identified in the ISO 175um
map and characterized via their FIR colours, luminosities and masses. With a
mean size of 800pc, they probably represent several clouds in chance projection
or giant cloud complexes. The 175um data point provides crucial information in
addition to the IRAS 60 and 100um data: At least two modified Planck curves
with temperatures of about 40K and 15-21K are necessary to fit the SEDs of the
knots. We distinguish between three types of knots - cold, medium, warm - in
order to recognize trends. Comparisons with radio and optical tracers show that
- statistically - the cold knots can be identified well with CO and HI radio
sources and thus might represent mainly molecular cloud complexes. The warm
knots coincide with known HII regions and supernova remnants. The medium knots
might contain a balanced mixture of molecular clouds and HII regions. The cold
knots have a considerable luminosity and their discovery raises the question of
hidden star formation. Though the optically dark dust lanes in M31 generally
match the FIR ring, surprisingly we do not find a convincing coincidence of our
knots with individual dark clouds which might therefore show mainly foreground
dust features. The ratio of FIR luminosity to dust mass, L/M, is used to
measure the energy content of the dust. The knots have a clear L/M excess over
the rest of M31, providing evidence that they are powered by star formation in
addition to the interstellar radiation field. The L/M ratio of the warm knots
is comparable to that of Galactic HII regions like M42 or NGC2024, while that
of the cold knots still reaches values like in the average Orion complex. Thus
both the warm and the cold knots are interpreted as containing large cloud
complexes with considerable ongoing star formation.

</DOC>
<DOC>
<DOCNO> 119519 </DOCNO>
Evidence of Rapid Optical Variability In Selected Narrow-Line Seyfert 1


  We present the first results of a search for the presence of rapid optical
variability in a sample of five Narrow-Line Seyfert 1 galaxies. We find clear
evidence of rapid variability for IRAS 13224-3809 with variations occurring on
time scales of an hour. However, the results are less conclusive for the other
four sources in our sample, Markarian 766, PG 1244+026, PG 1404+226 and
Arakelian 564. While there are several instances among these latter objects
where there is a hint that variability may be present, IRAS 13224-3809 provides
the only conclusive evidence of rapid optical variability detected to date.

</DOC>
<DOC>
<DOCNO> 81013 </DOCNO>
QCD with Adjoint Scalars in 2D: Properties in the Colourless Scalar


  We present a numerical study of an SU(3) gauged 2D model for adjoint scalar
fields, defined by dimensional reduction of pure gauge QCD in (2+1)D at high
temperature. In the symmetric phase of its global Z_2 symmetry, two colourless
boundstates, even and odd under Z_2, are identified. Their respective
contributions (poles) in correlation functions of local composite operators A_n
of degree n=2p and 2p+1 in the scalar fields (p=1,2) fulfill factorization. The
contributions of two particle states (cuts) are detected. Their size agrees
with estimates based on a meanfield-like decomposition of the p=2 operators
into polynomials in p=1 operators. No sizable signal in any A_n correlation can
be attributed to 1/n times a Debye screening length associated with n
elementary fields. These results are quantitatively consistent with the picture
of scalar ``matter'' fields confined within colourless boundstates whose
residual ``strong'' interactions are very weak.

</DOC>
<DOC>
<DOCNO> 13302 </DOCNO>
Nonextensive thermodynamic relations


  The generalized zeroth law of thermodynamics indicates that the physical
temperature in nonextensive statistical mechanics is different from the inverse
of the Lagrange multiplier, beta. This leads to modifications of some of
thermodynamic relations for nonextensive systems. Here, taking the first law of
thermodynamics and the Legendre transform structure as the basic premises, it
is found that Clausius definition of the thermodynamic entropy has to be
appropriately modified, and accordingly the thermodynamic relations proposed by
Tsallis, Mendes and Plastino [Physica A 261 (1998) 534] are also to be
rectified. It is shown that the definition of specific heat and the equation of
state remain form invariant. As an application, the classical gas model is
reexamined and, in marked contrast with the previous result obtained by Abe
[Phys. Lett. A 263 (1999) 424: Erratum A 267 (2000) 456] using the unphysical
temperature and the unphysical pressure, the specific heat and the equation of
state are found to be similar to those in ordinary extensive thermodynamics.

</DOC>
<DOC>
<DOCNO> 119669 </DOCNO>
Hyperbolic character of the angular moment equations of radiative


  We study the mathematical character of the angular moment equations of
radiative transfer in spherical symmetry and conclude that the system is
hyperbolic for general forms of the closure relation found in the literature.
Hyperbolicity and causality preservation lead to mathematical conditions
allowing to establish a useful characterization of the closure relations. We
apply numerical methods specifically designed to solve hyperbolic systems of
conservation laws (the so-called Godunov-type methods), to calculate numerical
solutions of the radiation transport equations in a static background. The
feasibility of the method in any kind of regime, from diffusion to
free-streaming, is demonstrated by a number of numerical tests and the effect
of the choice of the closure relation on the results is discussed.

</DOC>
<DOC>
<DOCNO> 169834 </DOCNO>
Remark on multi-particle observables and entangled states with constant


  We show that every density matrix of an n-particle system prepared by a
quantum network of constant depth is asymptotically commuting with the
mean-field observables. We introduce certain pairs of hypersurfaces in the
space of density matrices and give lower bounds for the depth of a network
which prepares states lying outside those pairs. The measurement of an
observable which is not asymptotically commuting with the mean-field
observables requires a network of depth in the order of log n, if one demands
the measurement to project the state into the eigenspace of the measured
observable.

</DOC>
<DOC>
<DOCNO> 117428 </DOCNO>
Young and Intermediate Stellar population in Seyfert 2 galaxies


  We present and discuss near-ultraviolet and optical ground-based spectra of
the 20 brightest Seyfert 2 nuclei, and HST ultraviolet images and ultraviolet
spectroscopy for a few of them. The goal is to study the starburst-AGN
connection and the origin of the featureless continuum. The results indicate
that half of the nuclei in the sample harbor a young and/or intermediate age
population. These stars are formed in powerful and dusty starbursts of short
duration, that have bolometric luminosities similar to the estimated bolometric
luminosities of their obscured Seyfert 1 nuclei.

</DOC>
<DOC>
<DOCNO> 102030 </DOCNO>
A Classification and Examples of Four-Dimensional Nonisoclinic


  A classification and examples of four-dimensional isoclinic three-webs of
codimension two are given. The examples considered prove the existence theorem
for many classes of webs for which the general existence theorems are not
proved yet.

</DOC>
<DOC>
<DOCNO> 100730 </DOCNO>
On the derived invariance of cohomology theories for coalgebras


  We study the derived invariance of the cohomology theories $Hoch^*$, $H^*$
and $HC^*$ associated to coalgebras over a field. We prove a theorem
characterizing derived equivalences. As particular cases, it describes the two
following situations: 1) $f:C\to D$ a quasi-isomorphism of differential graded
coalgebras, 2) the existence of a "cotilting" bicomodule ${}_CT_D$. In these
two cases we construct a derived-Morita equivalence context, and consequently
we obtain isomorphisms $Hoch^*(C)\cong\Hoch^*(D)$ and $H^*(C)\cong H^*(D)$.
Moreover, when we have a coassociative map inducing an isomorphism $H^*(C)\cong
H^*(D)$ (for example when there is a quasi-isomorphism $f:C\to D$), we prove
that $HC^*(C)\cong HC^*(D)$.

</DOC>
<DOC>
<DOCNO> 83106 </DOCNO>
Defeasible Reasoning in OSCAR


  This is a system description for the OSCAR defeasible reasoner.

</DOC>
<DOC>
<DOCNO> 39781 </DOCNO>
Germanium Detector with Internal Amplification for Investigation of Rare


  Device of new type is suggested - germanium detector with internal
amplification. Such detector having effective threshold about 10 eV opens up
fresh opportunity for investigation of dark matter, measurement of neutrino
magnetic moment, of neutrino coherent scattering at nuclei and for study of
solar neutrino problem. Construction of germanium detector with internal
amplification and perspectives of its use are described.

</DOC>
<DOC>
<DOCNO> 120911 </DOCNO>
The Antarctic Submillimeter Telescope and Remote Observatory (AST/RO)


  AST/RO, a 1.7 m diameter telescope for astronomy and aeronomy studies at
wavelengths between 200 and 2000 microns, was installed at the South Pole
during the 1994-1995 Austral summer. The telescope operates continuously
through the Austral winter, and is being used primarily for spectroscopic
studies of neutral atomic carbon and carbon monoxide in the interstellar medium
of the Milky Way and the Magellanic Clouds. The South Pole environment is
unique among observatory sites for unusually low wind speeds, low absolute
humidity, and the consistent clarity of the submillimeter sky. Four heterodyne
receivers, an array receiver, three acousto-optical spectrometers, and an array
spectrometer are installed. A Fabry-Perot spectrometer using a bolometric array
and a Terahertz receiver are in development. Telescope pointing, focus, and
calibration methods as well as the unique working environment and logistical
requirements of the South Pole are described.

</DOC>
<DOC>
<DOCNO> 101564 </DOCNO>
The Moduli of Flat PU(p,p)-Structures with Large Toledo Invariants


  For a compact Riemann surface $X$ of genus $g > 1$, $\Hom(\pi_1(X),
PU(p,q))/PU(p,q)$ is the moduli space of flat $PU(p,q)$-connections on $X$.
There are two invariants, the Chern class $c$ and the Toledo invariant $\tau$
associated with each element in the moduli. The Toledo invariant is bounded in
the range $-2min(p,q)(g-1) \le \tau \le 2min(p,q)(g-1)$. This paper shows that
the component, associated with a fixed $\tau > 2(max(p,q)-1)(g-1)$ (resp. $\tau
< -2(max(p,q)-1)(g-1)$) and a fixed Chern class $c$, is connected (The
restriction on $\tau$ implies $p=q$).

</DOC>
<DOC>
<DOCNO> 13988 </DOCNO>
Quantum fluctuations in superconducting dots at finite temperature


  We study the thermodynamics of ultrasmall metallic grains with level spacing
$\delta$ comparable or smaller than the pairing correlation energy, at finite
temperatures, $T \gsim \delta$. We describe a method which allows to find
quantum corrections to the effect of classical fluctuations. We present results
for thermodynamic quantities in ordered grains and for the reentrant odd
susceptibility in disordered grains.

</DOC>
<DOC>
<DOCNO> 7655 </DOCNO>
The Interacting Impurity Josephson Junction: Variational Wavefunctions


  We investigate the Josephson coupling between two superconductors mediated
through an infinite U Anderson impurity, adapting a variational wavefunction
approach which has proved successful for the Kondo model. Unlike the Kondo
problem, however, a crossing of singlet and doublet state energies may be
produced by varying the ratio of Kondo energy to superconducting gap, in
agreement with recent work of Clerk and Ambegaokar. We construct the phase
diagram for the junction and discuss properties of different phases. In
addition, we find the singlet and doublet state energies within a slave boson
mean field approach. We find the slave boson mean field treatment is unable to
account for the level crossing.

</DOC>
<DOC>
<DOCNO> 68885 </DOCNO>
Towards softer scales in hot QCD


  An effective theory for the soft field modes in hot QCD has been obtained
recently by integrating out the field modes of momenta of order T and g T. The
mean hard particle distribution obeys a transport equation with a collision
term. The scale that comes out for the soft field is g^2 T ln 1/g .
    N-gluon soft amplitudes are shown to be a sum of tree diagrams and to obey
tree-like Ward identities. These effective amplitudes are used to compute the
one-soft loop contribution to the gluon self-energy when the loop momentum is
of order g^2 T ln 1/g. It allows to identify a new collision term which, when
included into the transport equation, takes into account collisions with gluon
exchange of order g^2 T ln 1/g. The infrared behaviour of the collision term
exhibits a significant change.

</DOC>
<DOC>
<DOCNO> 119397 </DOCNO>
Interferometric Astrometry of the Low-mass Binary Gl 791.2 (= HU Del)


  With fourteen epochs of fringe tracking data spanning 1.7y from Fine Guidance
Sensor 3 we have obtained a parallax (pi_abs=113.1 +- 0.3 mas) and perturbation
orbit for Gl 791.2A. Contemporaneous fringe scanning observations yield only
three clear detections of the secondary on both interferometer axes. They
provide a mean component magnitude difference, Delta V = 3.27 +- 0.10. The
period (P = 1.4731 yr) from the perturbation orbit and the semi-major axis (a =
0.963 +- 0.007 AU) from the measured component separations with our parallax
provide a total system mass M_A + M_B = 0.412 +- 0.009 M_sun. Component masses
are M_A=0.286 +- 0.006 M_sun and M_B = 0.126 +- 0.003 M_sun. Gl 791.2A and B
are placed in a sparsely populated region of the lower main sequence
mass-luminosity relation where they help define the relation because the masses
have been determined to high accuracy, with errors of only 2%.

</DOC>
<DOC>
<DOCNO> 119347 </DOCNO>
On the velocity of the Vela pulsar


  It is shown that if the shell of the Vela supernova remnant is responsible
for nearly all the scattering of the Vela pulsar, then the scintillation and
proper motion velocities of the pulsar can only be reconciled with each other
in the case of nonzero transverse velocity of the scattering material. A
possible origin of large-scale transverse motions in the shell of the Vela
supernova remnant is discussed.

</DOC>
<DOC>
<DOCNO> 70540 </DOCNO>
Higher Twist Corrections and Maxima for DIS on a Proton in the High


  We show that the ratio of different structure functions have a maximum which
depends on energy. We argue, using Golec-Biernat and Wusthoff model, that these
maxima are the certain functions of the saturation scale. The analysis of
leading and higher twist contributions for different observables is given with
the aim of determining the kinematic region where high parton density effects
could be seen experimentally.

</DOC>
<DOC>
<DOCNO> 151682 </DOCNO>
Non-Abelian Duality in the String Effective Action


  We study the symmetry of the one-loop effective action of bosonic string
theory under non-Abelian T-duality transformations. It is shown that the
original Lagrangian and its dual are proportional. This result implies that the
corresponding reduced low energy effective actions are equivalent and leads to
a functional relation between the Weyl anomaly coefficients of the original and
dual two-dimensional non-linear sigma models. {}Finally, we apply this
formalism to some simple examples.

</DOC>
<DOC>
<DOCNO> 169870 </DOCNO>
Quantum computation with abelian anyons


  A universal quantum computer can be constructed using abelian anyons. Two
qubit quantum logic gates such as controlled-NOT operations are performed using
topological effects. Single-anyon operations such as hopping from site to site
on a lattice suffice to perform all quantum logic operations. Quantum
computation using abelian anyons shares some but not all of the robustness of
quantum computation using non-abelian anyons.

</DOC>
<DOC>
<DOCNO> 9959 </DOCNO>
Optical Properties of the Spin-Ladder Compound Sr_{14}Cu_{24}O_{41}


  We report the measurements of the pseudodielectric function, far-infrared
reflectivity and Raman scattering spectra in Sr_{14}Cu_{24}O_{41} single
crystal. We study the lattice and the spin dynamics of the Cu$_2$O$_3$ spin
ladders and CuO$_2$ chains of this compound. The ellipsometric and the optical
reflectivity measurements yield the gap values of 1.4 eV, 1.86 eV, 2.34 eV (2.5
eV) for the ladders (chains) along the {\bf c}-axis and 2.4 eV along the {\bf
a}-axis. The electronic structure of the Cu$_2$O$_3$ ladders is analyzed using
tight-binding approach for the correlated electron systems. The correlation gap
value of 1.4 eV is calculated with the transfer energy (hopping) parameters
$t=t_{0}$=0.26 eV, along and perpendicular to legs, $t_{xy}$=0.026 eV
(interladder hopping) and U=2.1 eV, as a Coulomb repulsion. The optical
parameters of the infrared active phonons and plasmons are obtained by
oscillator fitting procedure of the reflectivity spectra. Raman scattering
spectra are measured at different temperatures using different laser line
energies. The two-magnon peak is observed at about 2880 cm$^{-1}$. At
temperatures below 150 K the new infrared and Raman modes appear due to the
charge ordering.

</DOC>
<DOC>
<DOCNO> 72132 </DOCNO>
Probing Slepton Mass Non-Universality at e^+e^- Linear Colliders


  There are many models with non-universal soft SUSY breaking sfermion mass
parameters at the grand unification scale. Even in the mSUGRA model scalar mass
unification might occur at a scale closer to M_Planck, and renormalization
effects would cause a mass splitting at M_GUT. We identify an experimentally
measurable quantity Delta that correlates strongly with delta m^2 =
m^2_{selectron_R}(M_GUT) - m^2_{selectron_L}(M_GUT), and which can be measured
at electron-positron colliders provided both selectrons and the chargino are
kinematically accessible. We show that if these sparticle masses can be
measured with a precision of 1% at a 500 GeV linear collider, the resulting
precision in the determination of Delta may allow experiments to distinguish
between scalar mass unification at the GUT scale from the corresponding
unification at Q ~ M_Planck. Experimental determination of Delta would also
provide a distinction between the mSUGRA model and the recently proposed
gaugino-mediation model. Moreover, a measurement of Delta (or a related
quantity Delta') would allow for a direct determination of delta m^2.

</DOC>
<DOC>
<DOCNO> 11001 </DOCNO>
Anomalies in the conduction edge of quantum wires


  We study the conductance threshold of clean nearly straight quantum wires in
which an electron is bound. We show that such a system exhibits spin-dependent
conductance structures on the rising edge to the first conductance plateau, one
near 0.25(2e^2/h), related to a singlet resonance, and one near 0.75(2e^2/h),
related to a triplet resonance. As a quantitative example we solve exactly the
scattering problem for two-electrons in a wire with circular cross-section and
a weak bulge. From the scattering matrix we determine conductance via the
Landauer-Buettiker formalism. The conductance anomalies are robust and survive
to temperatures of a few degrees. With increasing magnetic field the
conductance exhibits a plateau at e^2/h, consistent with recent experiments.

</DOC>
<DOC>
<DOCNO> 99820 </DOCNO>
Hyperelliptic jacobians and modular representations


  In his previous paper (Math. Res. Letters 7(2000), 123--132) the author
proved that in characteristic zero the jacobian $J(C)$ of a hyperelliptic curve
$C: y^2=f(x)$ has only trivial endomorphisms over an algebraic closure of the
ground field $K$ if the Galois group $Gal(f)$ of the irreducible polynomial
$f(x) \in K[x]$ is either the symmetric group $S_n$ or the alternating group
$A_n$. Here $n>4$ is the degree of $f$.
  In the present paper we extend this result to the case of certain ``smaller''
Galois groups. In particular, we treat the case when $n=11$ or 12 and $Gal(f)$
is the Mathieu group $M_{11}$ or $M_{12}$ respectively. The infinite series
$n=2^r+1, Gal(f)=L_2(2^r)$ and $n=2^{4r+2}+1, Gal(f)=Sz(2^{2r+1})$ are also
treated.

</DOC>
<DOC>
<DOCNO> 100176 </DOCNO>
The c-function for non-compactly causal symmetric spaces


  In this paper we prove the product formula for the c-function of
non-compactly causal symmetric spaces.

</DOC>
<DOC>
<DOCNO> 151847 </DOCNO>
Reply to Comment on Dirac spectral sum rules for QCD in three dimensions


  I reply to the comment by Dr S. Nishigaki (hep-th/0007042) to my papers Phys.
Rev. D61 (2000) 056005 and Phys. Rev. D62 (2000) 016005.

</DOC>
<DOC>
<DOCNO> 72053 </DOCNO>
Excited Heavy Baryons and Their Symmetries II: Effective Theory


  We develop an effective theory for heavy baryons and their excited states.
The approach is based on the contracted O(8) symmetry recently shown to emerge
from QCD for these states in the combined large N_c and heavy quark limits. The
effective theory is based on perturbations about this limit; a power counting
scheme is developed in which the small parameter is lambda^{1/2} where lambda ~
1/N_c, Lambda /m_Q (with Lambda being a typical strong interaction scale). We
derive the effective Hamiltonian for strong interactions at next-to-leading
order. The next-to-leading order effective Hamiltonian depends on only two
parameters beyond the known masses of the nucleon and heavy meson. We also show
that the effective operators for certain electroweak transitions can be
obtained with no unknown parameters at next-to-leading order.

</DOC>
<DOC>
<DOCNO> 40321 </DOCNO>
Combined results on b-hadron production rates, lifetimes, oscillations


  Combined results on b-hadron lifetimes, b-hadron production rates, B^0_d -
\bar{B^0_d} and B^0_s -\bar{B^0_s} oscillations, the decay width difference
between the mass eigenstates of the B^0_s -\bar{B^0_s} system, and the values
of the CKM matrix elements | V_cb | and \Vert V_ub | are obtained from
published and preliminary measurements available in Summer 99 from the ALEPH,
CDF, DELPHI, L3, OPAL and SLD Collaborations.

</DOC>
<DOC>
<DOCNO> 178653 </DOCNO>
Breit-Wigner to Gaussian transition in strength functions


  Employing hamiltonians defined by two-body embedded Gaussian orthogonal
ensemble of random matrices(EGOE(2)) plus a mean-field producing one-body part,
strength functions (for states defined by the one-body part) are constructed
for various values of the strength of the chaos generating two-body part.
Numerical calculations for six and seven fermion systems clearly demonstrate
Breit-Wigner to Gaussian transition, in the chaotic domain, in strength
functions as found earlier in nuclear shell model and Lipkin-Meshkov-Glick
model calculations.

</DOC>
<DOC>
<DOCNO> 68395 </DOCNO>
Higher Order Corrections in Perturbative Quantum Chromo Dynamics


  We present some techniques which have been developed recently or in the
recent past to compute Feynman graphs beyond one-loop order. These techniques
are useful to compute the three-loop splitting functions in QCD and to obtain
the complete second order QED corrections to Bhabha scattering.

</DOC>
<DOC>
<DOCNO> 117141 </DOCNO>
The Law of Conservation of Energy in Chemical Reactions


  Earlier it has been supposed that the law of conservation of energy in
chemical reactions has the following form: DU=DQ-PDV+SUM(muiDN) In the present
paper it has been proved by means of the theory of ordinary differential
equations that in the biggest part of the chemical reactions it must have the
following form: DU=DQ+PDV+SUM(muiDN) The result obtained allows to explain a
paradox in chemical thermodynamics: the heat of chemical processes measured by
calorimetry and by the Vant-Hoff equation differs very much from each other.
The result is confirmed by many experiments.

</DOC>
<DOC>
<DOCNO> 12711 </DOCNO>
Quantum Phase Transitions in the Ising model in spatially modulated


  The phase transitions in the transverse field Ising model in a competing
spatially modulated (periodic and oscillatory) longitudinal field are studied
numerically. There is a multiphase point in absence of the transverse field
where the degeneracy for a longitudinal field of wavelength $\lambda$ is
$(\frac {1 + \sqrt{5}}{2})^{2N/\lambda}$ for a system with $N$ spins, an exact
result obtained from the known result for $\lambda =2$. The phase transitions
in the $\Gamma $ (transverse field) versus $h_0$ (amplitude of the longitudinal
field) phase diagram are obtained from the vanishing of the mass gap $\Delta$.
We find that for all the phase transition points obtained in this way, $\Delta
$ shows finite size scaling behaviour signifying a continuous phase transition
everywhere. The values of the critical exponents show that the model belongs to
the universality class of the two dimensional Ising model. The longitudinal
field is found to have the same scaling behaviour as that of the transverse
field, which seems to be a unique feature for the competing field. The phase
boundaries for two different wavelengths of the modulated field are obtained.
Close to the multiphase point at $h_c$, the phase boundary behaves as $(h_c -
h_0)^b$, where $b$ is also $\lambda$ dependent.

</DOC>
<DOC>
<DOCNO> 12317 </DOCNO>
Many-body Green's function theory for the magnetic reorientation of thin


  The field-induced reorientation of the magnetization of ferromagnetic films
is treated within the framework of many-body Green's function theory by
considering all components of the magnetization. We present a new method for
the calculation of expectation values in terms of the eigenvalues and
eigenvectors of the equations of motion matrix for the set of Green's
functions. This formulation allows a straightforward extension of the monolayer
case to thin films with many layers and for arbitrary spin and moreover
provides a practicable procedure for numerical computation. The model
Hamiltonian includes a Heisenberg term, an external magnetic field, a
second-order uniaxial single-ion anisotropy, and the magnetic dipole-dipole
coupling. We utilize the Tyablikov (RPA) decoupling for the exchange
interaction terms and the Anderson-Callen decoupling for the anisotropy terms.
The dipole coupling is treated in the mean-field approximation, a procedure
which we demonstrate to be a sufficiently good approximation for realistic
coupling strengths. We apply the new method to monolayers with spin $S\geq 1$
and to multilayer systems with S=1. We compare some of our results to those
where mean-field theory (MFT) is applied to all interactions, pointing out some
significant differences.

</DOC>
<DOC>
<DOCNO> 100964 </DOCNO>
The Calibration Method for Free Discontinuity Problems


  The calibration method is used to identify some minimizers of the
Mumford-Shah functional. The method is then extended to more general free
discontinuity problems.

</DOC>
<DOC>
<DOCNO> 80854 </DOCNO>
Determining gA using non-perturbatively O(a) improved Wilson fermions


  A completely non-perturbative estimate is given for gA using both quenched
and unquenched O(a) improved Wilson fermions. Particular attention is paid to
the determination of the axial renormalisation constant, ZA, using the Ward
identity for the propagator. For the quenched case, we have results at three
lattice spacings allowing a continuum extrapolation.

</DOC>
<DOC>
<DOCNO> 150778 </DOCNO>
Nonperturbative approach to a simple model with ultraviolet divergent


  We study a simple model for which perturbation theory gives ultravioletly
divergent results. We show that when the eigen-solution problem of the
Hamiltonian of the model is treated nonperturbatively, it is possible for
eigenenergies of the Hamiltonian to be finite.

</DOC>
<DOC>
<DOCNO> 116959 </DOCNO>
Dipole Mode Detuning in the NLC Injector Linacs


  The injector linacs of the JLC/NLC comprise the e+ booster, the e- drive
linac, the e+ booster, and the two prelinacs. These four systems together
transport the two types of beams from the 80 MeV point at the end of their
respective bunchers up to the storage rings, and then from the storage rings to
the 10 GeV point at the beginning of the bunch compressors. Nominally, the e+
booster structure will be L-band and the others S-band. In transport through
these linacs it is important that the emittances and particle losses stay
within specified tolerances. In particular, the effects of the dipole
wakefield-especially the long-range dipole wakefield-need to be carefully
considered. We present designs of the injector linac structures that employ
simple mode detuning, without damping, and that allow us to satisfy our
tolerance requirements, for both the nominal (2.8 ns) and alternate (1.4 ns)
bunch spacing options.

</DOC>
<DOC>
<DOCNO> 117346 </DOCNO>
Testing envelope models of young stellar objects with submillimeter


  This paper examines the density and velocity structure of envelopes around
young stellar objects through submillimeter continuum imaging of four objects
in Taurus and previously obtained molecular-line data. Observations carried out
with the SCUBA on the JCMT at 850 and 450 micron of L1489 IRS, L1535 IRS, L1527
IRS, and TMC 1 reveal ~2000 AU elongated structures embedded in extended
envelopes. The density distribution in these envelopes is equally well fit by a
radial power-law of index p=1.0-2.0 or with a collapse model such as that of
Shu (1997: ApJ, 214, 488). This inside-out collapse model predicts 13CO, C18O,
HCO+, and H13CO+ line profiles which closely match observed spectra toward
three of our four sources. This shows that the inside-out collapse model offers
a good description of YSO envelopes, but also that reliable constraints on its
parameters require independent measurements of the density and the velocity
structure, e.g., through continuum and line observations. For the remaining
source, L1489 IRS, we find that a model consisting of a 2000 AU radius,
rotating, disk-like structure better describes the data. Possibly, this source
is in transition between the embedded Class I and the optically revealed T
Tauri phases. Two apparently starless cores are found at ~10,000 AU from L1489
IRS and L1535 IRS. They are cold, 10-15 K, contain 0.5-3.0 M_sol, and have flat
density distributions characterized by a Gaussian of ~10,000 AU FWHM. The
proximity of these cores shows that star formation in truly isolated cores is
rare even in Taurus.

</DOC>
<DOC>
<DOCNO> 7699 </DOCNO>
Nonequilibrium Kinetic Ising Models: Phase Transition and Universality


  Nonequilibrium kinetic Ising models evolving under the competing effect of
spin flips at zero temperature and Kawasaki-type spin-exchange kinetics at
infinite temperature T are investigated here in one dimension from the point of
view of phase transition and critical behaviour. Branching annihilating random
walks with an even number of offspring (on the part of the ferromagnetic domain
boundaries), is a decisive process in forming the steady state of the system
for a range of parameters, in the family of models considered. A wide variety
of quantities characterize the critical behaviour of the system. Results of
computer simulations and of a generalized mean field theory are presented and
discussed.

</DOC>
<DOC>
<DOCNO> 71245 </DOCNO>
Lattice Field Theory


  This review concentrates on progress in lattice QCD during the last two years
and, particularly, its impact on phenomenology. The two main technical
developments have been successful implementations of lattice actions with exact
chiral symmetry, and results from simulations with two light dynamical flavours
which provide quantitative estimates of quenching effects for some quantities.
Results are presented for the hadron spectrum, quark masses, heavy-quark decays
and structure functions. Theoretical progress is encouraging renewed attempts
to compute non-leptonic kaon decays. Although computing power continues to be a
limitation, projects are underway to build multi-teraflops machines over the
next three years, which will be around ten times more cost-effective than those
of today.

</DOC>
<DOC>
<DOCNO> 69602 </DOCNO>
Leptoquarks and Contact Interactions from a Global Analysis


  Data from HERA, LEP and the Tevatron, as well as from low energy experiments
are used to constrain the scale of possible electron-quark contact
interactions. Some models are found to describe the existing experimental data
much better than the Standard Model. The possibility of scalar or vector
leptoquark contribution is studied using the Buchmuller-Ruckl-Wyler effective
model. Increase in the global probability observed for scenarios including S_1
or ~V_o leptoquark production/exchange corresponds to more than a 3 sigma
effect. Assuming that a real leptoquark signal is observed, calculated is an
allowed region in the coupling-mass plane.

</DOC>
<DOC>
<DOCNO> 13942 </DOCNO>
High Pressure Insulator-Metal Transition in Molecular Fluid Oxygen


  We report the first experimental evidence for a metallic phase in fluid
molecular oxygen. Our electrical conductivity measurements of fluid oxygen
under dynamic quasi-isentropic compression show that a non-metal/metal
transition occurs at 3.4 fold compression, 4500 K and 1.2 Mbar. We discuss the
main features of the electrical conductivity dependence on density and
temperature and give an interpretation of the nature of the electrical
transport mechanisms in fluid oxygen at these extreme conditions.

</DOC>
<DOC>
<DOCNO> 13508 </DOCNO>
Quantum kinetic theory of shift current electron pumping in


  We develop a theory of laser beam generation of shift currents in
non-centrosymmetric semiconductors. The currents originate when the excited
electrons transfer between different bands or scatter inside these bands, and
asymmetrically shift their centers of mass in elementary cells. Quantum kinetic
equations for hot-carrier distributions and expressions for the induced
currents are derived by nonequilibrium Green functions. In applications, we
simplify the approach to the Boltzmann limit and use it to model laser-excited
GaAs in the presence of LO phonon scattering. The shift currents are calculated
in a steady-state regime.

</DOC>
<DOC>
<DOCNO> 12592 </DOCNO>
Almost Non-Magnetic Ground State of the V4+ Ion: The case of BaVS3


  We have shown that the V4+ ion with 1 d electron can have almost non-magnetic
ground state under the action of the octahedral crystal field in the presence
of the spin-orbit coupling and off-cubic distortions. Such the situation occurs
in the hexagonal BaVS3. The fine discrete electronic structure with the
weakly-magnetic Kramers-doublet ground state is the reason for anomalous
properties of BaVS3.
  Keywords: crystal-field, spin-orbit, orbital moment. PACS: 71.70.E, 75.10.D

</DOC>
<DOC>
<DOCNO> 85000 </DOCNO>
Supergravity Brane Cosmologies


  Solitonic brane cosmologies are found where the world-volume is curved due to
the evolution of the dilaton field on the brane. In many cases, these may be
related to the solitonic Dp- and M5-branes of string and M-theory. An
eleven-dimensional interpretation of the D8-brane cosmology of the massive type
IIA theory is discussed in terms of compactification on a torus bundle.
Braneworlds are also found in Horava-Witten theory compactified on a Calabi-Yau
three-fold. The possibility of dilaton-driven inflation on the brane is
discussed.

</DOC>
<DOC>
<DOCNO> 68356 </DOCNO>
Transverse QCD Dynamics Near the Light Cone


  Starting from the QCD Hamiltonian in near-light cone coordinates, we study
the dynamics of the gluonic zero modes. Euclidean 2+1 dimensional lattice
simulations show that the gap at strong coupling vanishes at intermediate
coupling. This result opens the possibility to synchronize the continuum limit
with the approach to the light cone.

</DOC>
<DOC>
<DOCNO> 152004 </DOCNO>
The Low Energy Dynamics of Non-BPS Branes


  In this talk we will discuss the low energy dynamics of non-BPS branes
constructed as stable brane/anti-brane pairs at an orbifold. In particular we
will determine the effective field theory and compare its predictions with
those of the full open string theory. While the position and vector degrees of
freedom have the familiar form found in supersymmetric gauge theories, the
massless modes orginating in the tachyonic sector display novel non-commuting
flat directions. We will show that these flat directions persist to al orders
in alpha'. Finally we will briefly report on the open string loop corrections.

</DOC>
<DOC>
<DOCNO> 70834 </DOCNO>
Perturbative renormalization of moments of quark momentum, helicity and


  Using overlap as well as Wilson fermions, we have computed the one-loop
renormalization factors of ten non-singlet operators which measure the third
moment of quark momentum and helicity distributions (the lowest two having been
computed in a previous paper), as well as the lowest three moments of the $g_2$
structure function and the lowest two non-trivial moments of the $h_1$
transversity structure function (plus the tensor charge). These factors are
needed to extract physical observables from Monte Carlo simulations of the
corresponding matrix elements.
  An exact chiral symmetry is maintained in our calculations with overlap
fermions, and its most important consequence here is that the operators
measuring $g_2$ do not show any of the power-divergent mixings with operators
of lower dimension which are present in the Wilson case. Many of our results
for Wilson fermions are also new; for the remaining ones, we agree with the
literature except in one case. The computations have been carried out using the
symbolic language FORM, in a general covariant gauge, which turns out also to
be useful in checking the gauge-invariance of the final results.

</DOC>
<DOC>
<DOCNO> 69830 </DOCNO>
Are charge fluctuations a good signal for QGP?


  A recent proposal to study charge fluctuations as a possible signal of
quark-gluon plasma is discussed. It is shown that the "pion gas model"
considered as the reference sample is unrealistic and the expected signal from
plasma may be difficult to distinguish from that coming from "standard
collisions".

</DOC>
<DOC>
<DOCNO> 80938 </DOCNO>
Domain wall fermion calculation of nucleon g_A/g_V


  We present a preliminary domain-wall fermion lattice-QCD calculation of
isovector vector and axial charges, g_V and g_A, of the nucleon. Since the
lattice renormalizations, Z_V and Z_A, of the currents are identical with DWF,
the lattice ratio (g_A/g_V)^{lattice} directly yields the continuum value.
Indeed Z_V determined from the matrix element of the vector current agrees
closely with Z_A from a non-perturbative renormalization study of quark
bilinears. We also obtain spin related quantities Delta-q/g_V and delta-q/g_V.

</DOC>
<DOC>
<DOCNO> 13600 </DOCNO>
Microstructure Effects on Daily Return Volatility in Financial Markets


  We simulate a series of daily returns from intraday price movements initiated
by microstructure elements. Significant evidence is found that daily returns
and daily return volatility exhibit first order autocorrelation, but trading
volume and daily return volatility are not correlated, while intraday
volatility is. We also consider GARCH effects in daily return series and show
that estimates using daily returns are biased from the influence of the level
of prices. Using daily price changes instead, we find evidence of a significant
GARCH component. These results suggest that microstructure elements have a
considerable influence on the return generating process.

</DOC>
<DOC>
<DOCNO> 100008 </DOCNO>
Perturbation of $l^1$-copies and measure convergence in preduals of von


  Let L_1 be the predual of a von Neumann algebra with a finite faithful normal
trace. We show that a bounded sequence in L_1 converges to 0 in measure if and
only if each of its subsequences admits another subsequence which converges to
0 in norm or spans $l^1$ "almost isometrically". Furthermore we give a
quantitative version of an essentially known result concerning the perturbation
of a sequence spanning $l^1$ isomorphically in the dual of a C$^*$-algebra.

</DOC>
<DOC>
<DOCNO> 151710 </DOCNO>
St\"uckelberg Field Shiftting Quantization of Free-Particle on


  In this paper we quantize the free-particle on a D-dimensional sphere in an
unambiguous way by converting the second-class constraint using St\"uckelberg
field shiftting formalism. Further, we argument that this formalism is
equivalent to the BFFT constraint conversion method and show that the energy
spectrum is identical to the pure Laplace-Beltrami operator without additional
terms arising from the curvature of the sphere. We work out the gauge symmetry
generators with results consistent with those obtained through the nonlinear
implementation of the gauge symmetry

</DOC>
<DOC>
<DOCNO> 84440 </DOCNO>
Quantum Radiation of a Uniformly Accelerated Refractive Body


  We study quantum radiation generated by an accelerated motion of a small body
with a refractive index n which differes slightly from 1. To simplify
calculations we consider a model with a scalar massless field. We use the
perturbation expansion in a small parameter n-1 to obtain a correction to the
vacuum Hadamard function for a uniformly accelerated motion of the body. We
obtain the vacuum expectation for the energy density flux in the wave zone and
discuss its properties.

</DOC>
<DOC>
<DOCNO> 170077 </DOCNO>
Transmitting One Qubit Can Increase One Ebit Between Two Parties at Most


  Entanglement shared between two seperated parties could not be increased
without transmitting quantum system. We suggest the project to gain
entanglement shared between Alice and Bob by transmitting quantum system and a
nem scheme to achieve efficient rate of entanglement. It is proven that under
any local operations and communicating classically, to transmit one qubit
through an ideal or a noisy quantum channel can increase no more than one ebit
between two parties. Furthermore, the prior nonmaximally transmitted
entanglement could not be improved by subsequently transmitted qubit. Although
our proof is given in the measure of formation of entanglement, we believe that
the above conclusion is also hold independently of the measure of entanglement.

</DOC>
<DOC>
<DOCNO> 10113 </DOCNO>
Canonical Transformation of the Hubbard Model and W=0 Pairing:


  We have recently developed a canonical transformation of the Hubbard and
related models, valid for systems of arbitrary size and for the full plane;
this is particularly suited to study hole pairing. In this work we show that
exact diagonalization results of the one band Hubbard model for small clusters
with periodic boundary conditions agree well with the analytical ones obtained
by means of our canonical transformation. In the presence of a pairing
instability, the analytic approach allows us to identify the Cooper pairs. They
are W=0 pairs, that is, singlet two-hole eigenstates of the Hubbard Hamiltonian
with vanishing on-site repulsion. Indeed, we find that the Coulomb interaction
effects on W=0 pairs are dynamically small, and repulsive or attractive,
depending on the filling.

</DOC>
<DOC>
<DOCNO> 151664 </DOCNO>
Wess--Zumino terms and Duality


  We show the equivalence between Stuckelberg and Wess-Zumino methods of
restoration of gauge symmetries of the anomalous, Abelian, effective action, in
arbitrary even dimensions D=2k. We present dual version of Wess-Zumino terms
with the compensating field described by a Kalb-Ramond like p=2k-2 form.

</DOC>
<DOC>
<DOCNO> 10174 </DOCNO>
One-point functions in integrable coupled minimal models


  We propose exact vacuum expectation values of local fields for a quantum
group restriction of the $C_2^{(1)}$ affine Toda theory which corresponds to
two coupled minimal models. The central charge of the unperturbed models ranges
from $c=1$ to $c=2$, where the perturbed models correspond to two magnetically
coupled Ising models and Heisenberg spin ladders, respectively. As an
application, in the massive phase we deduce the leading term of the asymptotics
of the two-point correlation functions.

</DOC>
<DOC>
<DOCNO> 122072 </DOCNO>
Numerical simulations of turbulent dynamos


  Using a periodic box calculation it is shown that, owing to helicity
conservation, a large scale field can only develop on a resistive timescale.
This behaviour can be reproduced by a mean-field dynamo with alpha and eta_t
quenchings that are equally strong and `catastrophic'.

</DOC>
<DOC>
<DOCNO> 150561 </DOCNO>
Yang-Mills and Supersymmetry Covariance Must Coexist


  Supersymmetry and Yang-Mills type gauge invariance are two of the essential
properties of most, and possibly the most important models in fundamental
physics. Supersymmetry is nearly trivial to prove in the (traditionally
gauge-noncovariant) superfield formalism, whereas the gauge-covariant formalism
makes gauge invariance manifest. In 3+1-dimensions, the transformation from one
into the other is elementary and essentially unique. By contrast, this
transformation turns out to be impossible in the most general 1+1-dimensional
case. In fact, only the (manifestly) gauge- and supersymmetry-covariant
formalism guarantees both universal gauge-invariance and supersymmetry.

</DOC>
<DOC>
<DOCNO> 121814 </DOCNO>
News from the p-process: is the s-process a troublemaker?


  The most detailed calculations of the p-process call for its development in
the O/Ne layers of Type II supernovae. In spite of their overall success in
reproducing the solar system content of p-nuclides, they suggest a significant
underproduction of the light Mo and Ru isotopes. On grounds of a model for the
explosion of a 25 solar mass star with solar metallicity, we demonstrate that
this failure might just be related to the uncertainties left in the rate of the
22Ne(alpha,n)25Mg neutron producing reaction. The latter indeed has a direct
impact on the distribution of the s-process seeds for the p-process.

</DOC>
<DOC>
<DOCNO> 68987 </DOCNO>
On Energy Conservation in Lund String Fragmentation


  I discuss a Monte Carlo algorithm for hadronization in the Lund string
fragmentation picture, which conserves energy and momentum exactly as is
proposed by the model. An embryo to this Monte Carlo is used to calculate the
total decay density of a string. This is found to reach its predicted
asymptotic behaviour already at a string energy of about six hadron masses.

</DOC>
<DOC>
<DOCNO> 85490 </DOCNO>
Gravitational Energy-Momentum in MAG


  Energy-momentum (and angular momentum) for the Metric-Affine Gravity theory
is considered from a Hamiltonian perspective (linked with the Noether
approach). The important roles of the Hamiltonian boundary term and the many
choices involved in its selection-which give rise to many different
definitions-are emphasized. For each choice one obtains specific boundary
conditions along with a value for the quasilocal, and (with suitable asymptotic
behavior) total (Bondi and ADM) energy-momentum and angular momentum.
Applications include the first law of black hole thermodynamics-which
identifies a general expression for the entropy. Prospects for a positive
energy proof are considered and quasilocal values for some solutions are
presented.

</DOC>
<DOC>
<DOCNO> 84944 </DOCNO>
Quantum creation and inflationary universes: a critical appraisal


  We contrast the possibility of inflation starting a) from the universe's
inception or b) from an earlier non-inflationary state. Neither case is ideal
since a) assumes quantum mechanical reasoning is straightforwardly applicable
to the early universe; while case b) requires that a singularity still be
present. Further, in agreement with Vachaspati and Trodden [1] case b) can only
solve the horizon problem if the non-inflationary phase has equation of state
$\gamma<4/3$.

</DOC>
<DOC>
<DOCNO> 40482 </DOCNO>
Search for the Supersymmetric Partner of the Top-Quark in $p \bar{p}$


  We report on a search for the supersymmetric partner of the top quark (stop)
produced in $t \bar{t}$ events using $110 {\rm pb}^{-1}$ of $p \bar{p}$
collisions at $\sqrt{s} = 1.8 {\rm TeV}$ recorded with the Collider Detector at
Fermilab. In the case of a light stop squark, the decay of the top quark into
stop plus the lightest supersymmetric particle (LSP) could have a significant
branching ratio. The observed events are consistent with Standard Model $t
\bar{t}$ production and decay. Hence, we set limits on the branching ratio of
the top quark decaying into stop plus LSP, excluding branching ratios above 45%
for a LSP mass up to 40 {\rm GeV/c}$^{2}$.

</DOC>
<DOC>
<DOCNO> 8403 </DOCNO>
Modeling of Tunneling Spectroscopy in HTSC


  The tunneling density of states of HTSC is calculated taking into account
tight binding band structure, group velocity, and tunneling directionality for
s-wave and d-wave gap symmetry. The characteristic density of states has
quasiparticle peaks' asymmetry, flat s-wave and cusplike d-wave case subgap
behavior, and asymmetric background. We consider that the underlying asymmetry
of the conductance peaks is primarily due to the features of quasiparticle
energy spectrum, and the d-wave symmetry enhances the degree of the peaks'
asymmetry. Increasing of the lifetime broadening factor changes the degree of
tunneling conductance peaks' asymmetry, and leads to the confluence of the
quasiparticle and van Hove singularity peaks.

</DOC>
<DOC>
<DOCNO> 120344 </DOCNO>
Cygnus OB2 - a young globular cluster in the Milky Way


  The morphology and stellar content of the Cygnus OB2 association has been
determined using 2MASS infrared observations in the J, H, and K bands. The
analysis reveals a spherically symmetric association of 2 deg in diameter with
a half light radius of 13', corresponding to Rh = 6.4 pc at an assumed distance
of 1.7 kpc. The interstellar extinction for member stars ranges from Av = 5m to
20m, which led to a considerable underestimation of the association size and
richness in former optical studies. From the infrared colour-magnitude diagram,
the number of OB member stars is estimated to 2600 +/- 400, while the number of
O stars amounts to 120 +/- 20. This is the largest number of O stars ever found
in a galactic massive star association. The slope of the initial mass function
has been determined from the colour-magnitude diagram to Gamma=-1.6 +/- 0.1.
The total mass of Cyg OB2 is estimated to (4-10)*10^4 Msol, where the primary
uncertainty comes from the unknown lower mass cut-off. Using the radial density
profile of the association, the central mass density is determined to
rho0=40-150 Msol pc^-3. Considering the mass, density, and size of Cyg OB2 it
seems untenable to classify this object still as OB association. Cygnus OB2
more closely resembles a young globular cluster like those observed in the
Large Magellanic Cloud or in extragalactic star forming regions. It is
therefore suggested to re-classify Cygnus OB2 as young globular cluster - an
idea which goes back to Reddish et al. (1966). Cygnus OB2 would then be the
first object of this class in the Milky Way.

</DOC>
<DOC>
<DOCNO> 120731 </DOCNO>
Origin of the highest energy cosmic rays observed


  Introducing a simple Galactic wind model patterned after the solar wind we
show that back-tracing the orbits of the highest energy cosmic events suggests
that they may all come from the Virgo cluster, and so probably from the active
radio galaxy M87. This confirms a long standing expectation. Those powerful
radio galaxies that have their relativistic jets stuck in the interstellar
medium of the host galaxy, such as 3C147, will then enable us to derive limits
on the production of any new kind of particle, expected in some extensions of
the standard model in particle physics. New data from HIRES will be crucial in
testing the model proposed here.

</DOC>
<DOC>
<DOCNO> 152401 </DOCNO>
Casimir Effect, Hawking Radiation and Trace Anomaly


  The Casimir energy for massless scalar field of two parallel conductor, in
two dimensional Schwarzchild black hole background, with Dirichlet boundary
conditions is calculated by making use of general properties of renormalized
stress tensor. We show that vacuum expectation value of stress tensor can be
obtain by Casimir effect, trace anomaly and Hawking radiation. Four-dimensional
of this problem, by this method, is under progress by this author.

</DOC>
<DOC>
<DOCNO> 102306 </DOCNO>
Multi-parameter deformations of the module of symbols of differential


  The space of symbols of differential operators on a smooth manifold (i.e.,
the space of symmetric contravariant tensor fields) is naturally a module over
the Lie algebra of vector fields. We study, in the case of $\bf R^n$ with
$n\geq2$, multi-parameter formal deformations of this module. The space of
linear differential operators on $\bf R^n$ provides an important class of such
formal deformations; we show, however, that the whole space of deformations is
much larger.

</DOC>
<DOC>
<DOCNO> 151588 </DOCNO>
Static and non-static quantum effects in two-dimensional dilaton gravity


  We study backreaction effects in two-dimensional dilaton gravity. The
backreaction comes from an $R^2$ term which is a part of the one-loop effective
action arising from massive scalar field quantization in a certain
approximation. The peculiarity of this term is that it does not contribute to
the Hawking radiation of the classical black hole solution of the field
equations. In the static case we examine the horizon and the physical
singularity of the new black hole solutions. Studying the possibility of time
dependence we see the generation of a new singularity. The particular solution
found still has the structure of a black hole, indicating that non-thermal
effects cannot lead, at least in this approximation, to black hole evaporation.

</DOC>
<DOC>
<DOCNO> 118714 </DOCNO>
Turbulent mixing, viscosity, diffusion and gravity in the formation of


  Self-gravitational structure formation theory for astrophysics and cosmology
is revised using nonlinear fluid mechanics. Gibson's 1996-2000 theory balances
fluid mechanical forces with gravitational forces and density diffusion with
gravitational diffusion at critical viscous, turbulent, magnetic, and diffusion
length scales termed Schwarz scales. Instability occurs for scales larger than
the largest Schwarz scale rather than only for scales larger than the acoustic
scale introduced by Jeans 1902. From the new theory, the inner-halo-dark-matter
of galaxies consists of dark proto-globular-star-cluster (PGC) clumps of
small-planetary-mass objects called primordial fog particles (PFPs) formed soon
after decoupling at 300,000 years. PFPs explain Schild's 1996 "rogue planets
>... likely to be the missing mass" of a quasar lens-galaxy. WIMP dark matter
fluid is super-diffusive and fragments at large L_SD scales to form
outer-galaxy-halos. In the beginning of structure formation 30,000 years after
the Big Bang the viscous Schwarz scale L_SV matched the horizon scale L_H at
proto-galaxy-supercluster masses, decreasing to proto-galaxy fragments at
300,000 years. WIMP diffusivities from observed outer-halo (L_SD) scales
indicate WIMP particle masses in the neutrino rather than neutralino range.

</DOC>
<DOC>
<DOCNO> 102136 </DOCNO>
The Modular Tree of Pythagorus


  The Pythagorean triples have the structure of a ternary rooted tree; the tree
is based on the Cayley graph of a free subgroup of the modular group

</DOC>
<DOC>
<DOCNO> 9179 </DOCNO>
Polymer Crystallization in 25 nm Spheres


  Crystallization within the discrete spheres of a block copolymer mesophase
was studied by time-resolved x-ray scattering. The cubic packing of
microdomains, established by self-assembly in the melt, is preserved throughout
crystallization by strong interblock segregation even though the amorphous
matrix block is well above its glass transition temperature. Homogeneous
nucleation within each sphere yields isothermal crystallizations which follow
first-order kinetics, contrasting with the sigmoidal kinetics normally
exhibited in the quiescent crystallization of bulk polymers.

</DOC>
<DOC>
<DOCNO> 122506 </DOCNO>
An observational constraint on gravitational lensing by objects of mass


  A radio-based search for strong gravitational lensing, with image separations
in the range 160-300 milliarcsec (mas), has yielded a null result for a sample
of 1665 sources (Augusto, Wilkinson & Browne 1998) whose mean redshift is
estimated to be ~1.3. The lensing rate for this previously-unexplored
separation range, <1:555 at the 95% confidence level, is less than on
arcsecond-scales - as expected from models of lensing galaxy populations.
Lensing on 160-300 mas scales is expected to arise predominantly from spiral
galaxies at a rate dependent on the disk-halo mass ratio and the evolving
number density of the population with redshift. While the present sample is too
small for there to be a high probability of finding spiral galaxy lenses, our
work is a pilot survey for a much larger search based on the full CLASS
database which would provide useful information on galactic structure at z~0.5.
We examine other possible lens populations relevant to our present search, in
particular dwarf galaxies and supermassive black holes in galactic nuclei, and
conclude that none of them are likely to be detected. Our null result enables
us formally to rule out a cosmologically significant population of
uniformly-distributed compact objects: Omega (CO)<0.1 (95% confidence) in the
mass range 10^(9.5) - 10^(10.9) Mo.

</DOC>
<DOC>
<DOCNO> 70640 </DOCNO>
A Next-to-Leading Order Calculation of Hadronic Three Jet Production


  We present results of a next-to-leading order calculation of three jet
production at hadron colliders. This calculation will have many applications.
In addition to computing such three-jet observables as spectra, mass
distributions, this calculation permits the first next-to-leading order studies
at hadron colliders of jet and event shape variables.

</DOC>
<DOC>
<DOCNO> 101659 </DOCNO>
Max-Min Representation of Piecewise Linear Functions


  It is shown that a piecewise linear function can be represented as a Max-Min
polynomial of its linear components.

</DOC>
<DOC>
<DOCNO> 151484 </DOCNO>
A Note on the Weyl Anomaly in the Holographic Renormalization Group


  We give a prescription for calculating the holographic Weyl anomaly in
arbitrary dimension within the framework based on the Hamilton-Jacobi equation
proposed by de Boer, Verlinde and Verlinde. A few sample calculations are made
and shown to reproduce the results that are obtained to this time with a
different method. We further discuss continuum limits, and argue that the
holographic renormalization group may describe the renormalized trajectory in
the parameter space. We also clarify the relationship of the present formalism
to the analysis carried out by Henningson and Skenderis.

</DOC>
<DOC>
<DOCNO> 101475 </DOCNO>
Ergodicity of Mapping Class Group Actions on Representation Varieties,


  The mapping class group of a compact oriented surface of genus greater than
one with boundary acts ergodically on connected components of the
representation variety corresponding to a connected compact Lie group, for
every choice of conjugacy class boundary condition.

</DOC>
<DOC>
<DOCNO> 120923 </DOCNO>
Cosmic concordance and the fine structure constant


  Recent measurements of a peak in the angular power spectrum of the cosmic
microwave background appear to suggest that geometry of the universe is close
to being flat. But if other accepted indicators of cosmological parameters are
also correct then the best fit model is marginally closed, with the peak in the
spectrum at larger scales than in a flat universe. Such observations can be
reconciled with a flat universe if the fine structure constant had a lower
value at earlier times, which would delay the recombination of electrons and
protons and also act to suppress secondary oscillations as observed. We discuss
evidence for a few percent increase in the fine structure constant between the
time of recombination and the present.

</DOC>
<DOC>
<DOCNO> 71247 </DOCNO>
Transverse momentum spectra of identified particles in high energy


  A detailed analysis is performed of transverse momentum spectra of several
identified hadrons in high energy collisions within the framework of the
statistical model of hadronisation. The effect of the decay chain following
hadron generation is accurately taken into account. The considered
centre-of-mass energies range from ~ 10 to 30 GeV in hadronic collisions (pi+
p, pp and Kp) and from ~ 15 to 45 GeV in e+e- collisions. A clear consistency
is found between the temperature parameter extracted from the present analysis
and that obtained from fits to average hadron multiplicities in the same
collision systems. This finding indicates that in the hadronisation, the
production of different particle species and their momentum spectra are two
closely related phenomenons governed by one parameter.

</DOC>
<DOC>
<DOCNO> 102904 </DOCNO>
Describing coherent sheaves on projective spaces via Koszul duality


  A new section on projections of coherent sheaves from a projective space to a
lower-dimensional projective space has been added.
   Also some of the notation has been altered to bring it into line with the
joint paper with Eisenbud and Schreyer.

</DOC>
<DOC>
<DOCNO> 71091 </DOCNO>
Large Mixing Angle MSW Solution in U(1) Flavor Symmetry


  We have discussed the quark-lepton mass matrices with the U(1) flavor
symmetry in SU(5), which lead to the large mixing angle MSW solution of solar
neutrinos. The solar neutrino solution depends on the next-leading terms in the
neutrino mass matrix. We have found the lepton mass matrices with the
$U(1)\times Z_2$ symmetry, which give the LMA-MSW solution uniquely. The
coefficients of the matrix elements of the charged leptons are constrained
strongly due to the bound of $U_{e3}$ in the CHOOZ experiment.

</DOC>
<DOC>
<DOCNO> 101670 </DOCNO>
Optimal Acoustic Measurements


  We consider the problem of obtaining information about an inaccessible
half-space from acoustic measurements made in the accessible half-space. If the
measurements are of limited precision, some scatterers will be undetectable
because their scattered fields are below the precision of the measuring
instrument. How can we make measurements that are optimal for detecting the
presence of an object? In other words, what incident fields should we apply
that will result in the biggest measurements?
  There are many ways to formulate this question, depending on the measuring
instruments. In this paper we consider a formulation involving wave-splitting
in the accessible half-space: what downgoing wave will result in an upgoing
wave of greatest energy?
  A closely related question arises in the case when we have a guess about the
configuration of the inaccessible half-space. What measurements should we make
to determine whether our guess is accurate? In this case we compare the
scattered field to the field computed from the guessed configuration. Again we
look for the incident field that results in the greatest energy difference.
  We show that the optimal incident field can be found by an iterative process
involving time reversal ``mirrors''. For band-limited incident fields and
compactly supported scatterers, in the generic case this iterative process
converges to a single time-harmonic field. In particular, the process
automatically "tunes" to the best frequency. This analysis provides a
theoretical foundation for the frequency-shifting and pulse-broadening observed
in certain computations and time-reversal experiments.

</DOC>
<DOC>
<DOCNO> 122532 </DOCNO>
A possible black hole binary in Mkn 501


  A simple binary model for Mkn~501 is considered under the assumption that the
TeV and X-ray periodicity of $\sim 23$ days, observed during the flaring state
in 1997, may be basically interpreted as a doppler-shifted flux modulation due
to the orbital motion of the relativistic jet. For the typical jet properties
inferred from emission models, we find an intrinsic orbital period of $(6-14)$
yrs and a centre-of-mass distance of $(2-3.5) \times 10^{16}$ cm, the binary
thus being a very close system. If the binary separation corresponds to that at
which gravitational radiation becomes dominant, one may obtain a maximum
allowed primary mass of $\sim 10^8 M_{\odot}$ and a corresponding maximum
allowed secondary mass in the range of $\sim (1-9)\times 10^7 M_{\odot}$
assuming that gas accretion occurs on around the salpeter time scale.
Interestingly such values agree with the black hole masses expected from merger
scenarios.

</DOC>
<DOC>
<DOCNO> 118272 </DOCNO>
First VLT spectra of white dwarfs in a globular cluster


  We present the first spectra obtained with the Very Large Telescope for white
dwarfs in a globular cluster. Estimates of atmospheric parameters are obtained
and compared to evolutionary tracks. We discuss possible implications for the
distance scale of globular clusters and white dwarf evolution and demonstrate
how white dwarfs might be used to establish an independent distance scale to
globular clusters.

</DOC>
<DOC>
<DOCNO> 100189 </DOCNO>
Compactness Theorems for Invariant Connections


  Necessary and sufficient conditions are given for the Palais-Smale Condition
C to hold for the Yang-Mills functional for connections that are invariant
under a Lie group action on the manifold with orbits of codimension less than
or equal to three. As an application the mountain pass lemma is used to give a
simple proof of Wang's theorem on the existence of irreducible
non-(anti-)selfdual instantons on S^2 x S^2 .

</DOC>
<DOC>
<DOCNO> 7646 </DOCNO>
An effective theory for conductance by symmetry breaking


  An effective theory is suggested for the particle-anti particle and the
particle-particle modes of strongly disordered electron systems. The effective
theory is studied in the framework of the saddle point expansion and found to
support a vacuum which is not invariant under translations in imaginary time.
The Goldstone bosons of this symmetry breaking generate a pole in the
density-density correlation function. The condensate of the auxiliary field
corresponding to the particle-particle channel produces conductivity without
relying on the long range fluctuations. The results are obtained for $d>1$.

</DOC>
<DOC>
<DOCNO> 84287 </DOCNO>
The Case for Inertia as a Vacuum Effect: A Reply to Woodward and Mahood


  The possibility of an extrinsic origin for inertial reaction forces has
recently seen increased attention in the physical literature. Among theories of
extrinsic inertia, the two considered by the current work are (1) the
hypothesis that inertia is a result of gravitational interactions, and (2) the
hypothesis that inertial reaction forces arise from the interaction of material
particles with local fluctuations of the quantum vacuum. A recent article
supporting the former and criticizing the latter is shown to contain
substantial errors.

</DOC>
<DOC>
<DOCNO> 119122 </DOCNO>
Astrophysical Reaction Rates From Statistical Model Calculations


  Theoretical reaction rates in the temperature range 0.01*10^9<=T[K]<=10.*10^9
are calculated in the statistical model (Hauser-Feshbach formalism) for targets
with 10<=Z<=83 (Ne to Bi) and for a mass range reaching the neutron and proton
driplines. Reactions considered are (n,gamma), (n,p), (n,alpha), (p,gamma),
(p,alpha),(alpha,gamma), and their inverse reactions. Reaction rates as a
function of temperature for thermally populated targets are given by analytic
seven parameter fits. To facilitate comparison with experimental rates, the
stellar enhancement factors are also tabulated. Two complete sets of rates have
been calculated, one of which includes a phenomenological treatment of shell
quenching for neutron-rich nuclei. These extensive datasets are provided
on-line as electronic files, while a selected subset from one calculation is
given as printed tables. A summary of the theoretical inputs and advice on the
use of the provided tabulations is included.

</DOC>
<DOC>
<DOCNO> 69688 </DOCNO>
Is $U_{e3}$ really related to the solar neutrino solutions?


  It has been said that the measurements of $U_{e3}$ in the lepton flavor
mixing matrix would help discriminate between the possible solar neutrino
solutions under the natural conditions with the neutrino mass hierarchies of
$m_1 \ll m_2 \ll m_3$ and $m_1 \sim m_2 \gg m_3$, where $m_i$ is the $i$-th
generation neutrino absolute mass. However, it is not true, and the relation
between $\sin^2 2 \theta_{12}$ and $U_{e3}$ obtained by Akhmedov, Branco, and
Rebelo is trivial in actual. We show in this paper that the value of $U_{e3}$
cannot predict the solar neutrino solutions without one additional nontrivial
condition.

</DOC>
<DOC>
<DOCNO> 101900 </DOCNO>
Quantum groups and Fuss-Catalan algebras


  The categories of representations of compact quantum groups of automorphisms
of certain inclusions of finite dimensional C*-algebras are shown to be
isomorphic to the categories of Fuss-Catalan diagrams.

</DOC>
<DOC>
<DOCNO> 12275 </DOCNO>
Single-Block Renormalization Group: Quantum Mechanical Problems


  We reformulate the density matrix renormalization group method (DMRG) in
terms of a single block, instead of the standard left and right blocks used in
the construction of the superblock. This version of the DMRG, which we call the
puncture renormalization group (PRG), makes easy and natural the extension of
the DMRG to higher dimensional lattices. To test numerically this proposal, we
study several quantum mechanical models in one, two and three dimensions. In 1D
the performance of the standard DMRG is much better than its PRG version,
however for 2D models the PRG is more efficient than the DMRG in a variety of
circumstances. In 3D the PRG performs also quite well.

</DOC>
<DOC>
<DOCNO> 116237 </DOCNO>
Evolution in the Multiverse


  In the {\em Many Worlds Interpretation} of quantum mechanics, the range of
possible worlds (or histories) provides variation, and the Anthropic Principle
is a selective principle analogous to natural selection. When looked on in this
way, the ``process'' by which the laws and constants of physics is determined
not too different from the process that gave rise to our current biodiversity,
i.e. Darwinian evolution. This has implications for the fields of SETI and
Artificial Life, which are based on a philosophy of the inevitability of life.

</DOC>
<DOC>
<DOCNO> 117937 </DOCNO>
The Luminosity Function of MS2255.7+2039 at z=0.288


  The luminosity function of MS2255.7+2039 at z=0.288 is determined down to a
total magnitude of R ~ 24, corresponding to M_R ~ -17 (H_0 = 50 km/s/Mpc). The
data are corrected for incompleteness and crowding using detailed simulations.
We find that the luminosity function is steeper than a standard Schechter
function at faint magnitudes, and shows an excess of galaxies below M_R ~ -19.
After corrections for light loss and crowding, the data can be described by a
sum of two Schechter functions, one with M_R = -22.8 and alpha = -1.0, and one
steeper with M_R = -18.9 and alpha = -1.5, representing the dwarf population. A
straight-line fit to the faint part yields a slope similar to the Schechter
alpha = -1.5 of the dwarf population. The luminosity function of MS2255.7+2039
is compared to other clusters at lower redshifts, and does not show any
significant difference. The redshift range for clusters in which increased
number of dwarf galaxies have been found is therefore extended to higher
redshifts.

</DOC>
<DOC>
<DOCNO> 119938 </DOCNO>
Self-Regulation of Star Formation in Low Metallicity Clouds


  We investigate the process of self-regulated star formation via
photodissociation of hydrogen molecules in low metallicity clouds. We evaluate
the influence region's scale of a massive star in low metallicity gas clouds
whose temperatures are between 100 and 10000 Kelvin. A single O star can
photodissociate hydrogen molecules in the whole of the host cloud. If
metallicity is smaller than about 10^{-2.5} of the solar metallicity, the
depletion of coolant of the the host cloud is very serious so that the cloud
cannot cool in a free-fall time, and subsequent star formation is almost
quenched. On the contrary, if metallicity is larger than about 10^{-1.5} of the
solar metallicity, star formation regulation via photodissociation is not
efficient. The typical metallicity when this transition occurs is about 1/100
of the solar metallicity. This indicates that stars do not form efficiently
before the metallicity becomes larger than about 1/100 of the solar metallicity
and we considered that this value becomes the lower limit of the metallicity of
luminous objects such as galaxies.

</DOC>
<DOC>
<DOCNO> 120551 </DOCNO>
Physical Processes at Cosmic Dawn


  In this summary paper I will focus on the four main topics discussed at this
Conference: (i) First luminous sources in the universe, (ii) Reionization,
(iii) Intergalactic medium and (iv) Galaxy formation. In addition to provide a
necessarily sketchy summary of the various talks on these subjects, I will also
outline some of potentially important issues that still need to be fully
addressed.

</DOC>
<DOC>
<DOCNO> 118147 </DOCNO>
Correlation of Quantized Spectrally-Varying Noise


  We compute statistics for correlation of quantized, spectrally-varying,
noise. We compare results with computer simulations and with radio-astronomical
observations. We consider cross-correlation of two signals (or auto-correlation
of one); we suppose that each signal is complex, and consists of
spectrally-varying Gaussian noise. We suppose that these signals are quantized,
and then correlated. For many samples, the correlation is drawn from a Gaussian
distribution at each frequency, and is completely characterized by its average
and variance. The average is linearly related to the average correlation of the
analog signals. We present expressions for the variance, and compare results
with computer simulations and with VLBI observations of the Vela pulsar. We
find excellent agreement. These results are important for understanding the
statistics of radio-astronomical observations, particularly of sources that
vary with time and observing frequency.

</DOC>
<DOC>
<DOCNO> 151707 </DOCNO>
Dualization of non-Abelian BF model


  We show that dualization of BF models to Stueckelberg-like massive gauge
theories allows a non-Abelian extension. We obtain local Lagrangians which are
straightforward extensions of the Abelian results.

</DOC>
<DOC>
<DOCNO> 12669 </DOCNO>
Midgap edge states and pairing symmetry of quasi-one-dimensional organic


  The singlet s-, d- and triplet p-wave pairing symmetries in
quasi-one-dimensional organic superconductors can be experimentally
discriminated by probing the Andreev bound states at the sample edges. These
states have the energy in the middle of the superconducting gap and manifest
themselves as a zero-bias peak in tunneling conductance into the corresponding
edge. Their existence is related to the sign change of the pairing potential
around the Fermi surface. We present an exact self-consistent solution of the
edge problem showing the presence of the midgap states for p_x-wave
superconductivity. The spins of the edge state respond paramagnetically to a
magnetic field parallel to the vector d that characterizes triplet pairing.

</DOC>
<DOC>
<DOCNO> 68638 </DOCNO>
Parametric amplification with a friction in heavy ion collisions


  We study the effects of the expansion of the system and the friction on the
parametric amplification of mesonic fields in high energy heavy ion collisions
within the linear $\sigma$ model . The equation of motion which is similar to
Mathieu equation is derived to describe the time development of classical
fields in the last stage of a heavy ion collision after the freezeout time. The
enhanced mode is extracted analytically by comparison with Mathieu equation and
the equation of motion is solved numerically to examine whether soft modes will
be enhanced or not. It is found that the strong peak appears around 267 MeV in
the pion transverse momentum distribution in cases with weak friction and high
maximum temperature. This enhancement can be extracted by taking the ratio
between different modes in the pion transverse momentum distribution.

</DOC>
<DOC>
<DOCNO> 122038 </DOCNO>
Can dusty Lyman break galaxies produce the submillimeter counts and


  Can the submillimeter counts and background be produced by applying a locally
derived extinction correction to the population of Lyman break galaxies? We
investigate the submillimeter emission of two strongly lensed Lyman break
galaxies (MS1512+36-cB58 and MS1358+62-G1) and find that the procedure that is
used to predict the submillimeter emission of the Lyman break galaxy population
overpredicts the observed 850micron fluxes by up to a factor of 14. This result
calls for caution in applying local correlations to distant galaxies. It also
shows that large extinction corrections on Lyman break galaxies should be
viewed with skepticism. It is concluded that the Lyman break galaxies may
contribute to the submillimeter background at the 25 to 50% level. The brighter
submillimeter galaxies making up the rest of the background are either not
detected in optical surveys, or if they are detected, their submillimeter
emission cannot be reliably estimated from their rest-frame ultraviolet
properties.

</DOC>
<DOC>
<DOCNO> 100327 </DOCNO>
A residue of complex function in three-dimensional vector space


  In the introduction part of this paper, first of all, the concept of absolute
integral sum of complex function is defined, as more general one with respect
to the concept of integral as well as of integral sum of "ordinary'' integral
calculus. In the main part of the paper, on the basis of redefined concepts of
a spatial derivative as well as of a residue of a complex function, the
fundamental results of Cauchy's calculus of residues of analytic functions are
generalized and the concept of total value of improper integral of complex
function is defined. Finally, the results in the form of fundamental lemmas,
which are more general with respect to the results of Jordan's fundamental
lemmas of Cauchy's calculus of residues of analytic functions, are derived for
the general class of scalar complex function whose defining domain is a complex
plane.

</DOC>
<DOC>
<DOCNO> 150462 </DOCNO>
Spin Observables and Path Integrals


  We discuss the formulation of spin observables associated to a
non-relativistic spinning particles in terms of grassmanian differential
operators. We use as configuration space variables for the pseudo-classical
description of this system the positions $x$ and a Grassmanian vector
$\vec\epsilon$. We consider an explicit discretization procedure to obtain the
quantum amplitudes as path integrals in this superspace. We compute the quantum
action necessary for this description including an explicit expression for the
boundary terms. Finally we shown how for simple examples, the path integral may
be performed in the semi-classical approximation, leading to the correct
quantum propagator.

</DOC>
<DOC>
<DOCNO> 150400 </DOCNO>
Small Instanton Transitions in Heterotic M-Theory


  We discuss non-perturbative phase transitions, within the context of
heterotic M-theory, which occur when all, or part, of the wrapped five-branes
in the five-dimensional bulk space come into direct contact with a boundary
brane. These transitions involve the transformation of the five-brane into a
``small instanton'' on the Calabi-Yau space at the boundary brane, followed by
the ``smoothing out'' of the small instanton into a holomorphic vector bundle.
Small instanton phase transitions change the number of families, the gauge
group or both on the boundary brane, depending upon whether a base component,
fiber component or both components of the five-brane class are involved in the
transition. We compute the conditions under which a small instanton phase
transition can occur and present a number of explicit, phenomenologically
relevant examples.

</DOC>
<DOC>
<DOCNO> 116811 </DOCNO>
Numerical Analysis of a Beam-Energy-Spread Monitor Using Multi-Stripline


  A beam-energy-spread monitor is under development in order to control and
stabilize the energy spread of high-current single-bunch electron beams for
producing a sufficient number of positrons. The author has proposed a new
monitor using multi-stripline electrodes in order to reinforce this purpose.
This report describes the basic design of the monitor based on a numerical
analysis. The analysis result shows that the resolution of an energy-spread
measurement is expected to be less than 0.3% for nominal operation conditions.

</DOC>
<DOC>
<DOCNO> 119409 </DOCNO>
FUSE Observations of the Stellar Winds of Two O7 Supergiants in the


  We compare the stellar wind features in far-UV spectra of Sk -67 111, an O7
Ib(f) star in the LMC, with Sk 80, an O7 Iaf+ star in the SMC. The most
striking differences are that Sk 80 has a substantially lower terminal
velocity, much weaker O VI absorption, and stronger S IV emission. We have used
line-blanketed, hydrodynamic, non-LTE atmospheric models to explore the origin
of these differences. The far-UV spectra require systematically lower stellar
temperatures than previous determinations for O7 supergiants derived from
plane-parallel, hydrostatic models of photospheric line profiles. At these
temperatures, the O VI in Sk -67 111 must be due primarily to shocks in the
wind.

</DOC>
<DOC>
<DOCNO> 83211 </DOCNO>
An Average Analysis of Backtracking on Random Constraint Satisfaction


  In this paper we propose a random CSP model, called Model GB, which is a
natural generalization of standard Model B. It is proved that Model GB in which
each constraint is easy to satisfy exhibits non-trivial behaviour (not
trivially satisfiable or unsatisfiable) as the number of variables approaches
infinity. A detailed analysis to obtain an asymptotic estimate (good to 1+o(1))
of the average number of nodes in a search tree used by the backtracking
algorithm on Model GB is also presented. It is shown that the average number of
nodes required for finding all solutions or proving that no solution exists
grows exponentially with the number of variables. So this model might be an
interesting distribution for studying the nature of hard instances and
evaluating the performance of CSP algorithms. In addition, we further
investigate the behaviour of the average number of nodes as r (the ratio of
constraints to variables) varies. The results indicate that as r increases,
random CSP instances get easier and easier to solve, and the base for the
average number of nodes that is exponential in r tends to 1 as r approaches
infinity. Therefore, although the average number of nodes used by the
backtracking algorithm on random CSP is exponential, many CSP instances will be
very easy to solve when r is sufficiently large.

</DOC>
<DOC>
<DOCNO> 8984 </DOCNO>
A Collection of Exercises in Two-Dimensional Physics, Part 1


  This document is an introduction to and review of two-dimensional
mathematical physics. The reader is introduced to the subject matter primarily
through problems, which are presented along with detailed worked solutions. For
each chapter, there is a brief summary of important results and ideas that
precedes the problems and the solutions. This document can be worked through
independently by one wishing to learn this subject; alternatively, this could
serve as a companion to a more conventional review article or textbook on the
subject.
  The current release contains Part I, and includes six chapters:
  1. Curiosities In 2 Dimensions 2. General Principles Of Conformal Field
Theory 3. Correlators In Critical Models 4. Other Models In Conformal Field
Theory 5. Construction Of New Models 6. Modular Invariance

</DOC>
<DOC>
<DOCNO> 71414 </DOCNO>
Detection Limits for Super-Hubble Suppression of Causal Fluctuations


  We investigate to what extent future microwave background experiments might
be able to detect a suppression of fluctuation power on large scales in flat
and open universe models. Such suppression would arise if fluctuations are
generated by causal processes, and a measurement of a small suppression scale
would be problematic for inflation models, but consistent with many defect
models. More speculatively, a measurement of a suppression scale of the order
of the present Hubble radius could provide independent evidence for a
fine-tuned inflation model leading to a low-density universe. We find that,
depending on the primordial power spectrum, a suppression scale modestly larger
than the visible Horizon can be detected, but that the detectability drops very
rapidly with increasing scale. For models with two periods of inflation, there
is essentially no possibility of detecting a causal suppression scale.

</DOC>
<DOC>
<DOCNO> 117894 </DOCNO>
The 35-Day Evolution of the Hercules X-1 Pulse Profile: Evidence For A


  Ginga and Rossi X-ray Timing Explorer (RXTE) observations have allowed an
unprecedented view of the recurrent systematic pulse shape changes associated
with the 35-day cycle of Hercules X-1, a phenomenon currently unique among the
known accretion-powered pulsars. We present observations of the pulse shape
evolution. An explanation for the pulse evolution in terms of a freely
precessing neutron star is reviewed and shown to have several major
difficulties in explaining the observed pulse evolution pattern. Instead, we
propose a phenomenological model for the pulse evolution based upon an
occultation of the pulse emitting region by the tilted, inner edge of a
precessing accretion disk. The systematic and repeating pulse shape changes
require a resolved occultation of the pulse emission region. The observed pulse
profile motivates the need for a pulsar beam consisting of a composite coaxial
pencil and fan beam but the observed evolution pattern requires the fan beam to
be focused around the neutron star and beamed in the antipodal direction. The
spectral hardness of the pencil beam component suggests an origin at the
magnetic polar cap, with the relatively softer fan beam emission produced by
backscattering from within the accretion column, qualitatively consistent with
several theoretical models for X-ray emission from the accretion column of an
accreting neutron star.

</DOC>
<DOC>
<DOCNO> 71376 </DOCNO>
Modification of Kawai model about the mixing of the pseudoscalar mesons


  The Kawai model describing the glueball-quarkonia mixing is modified. The
mixing of $\eta$, $\eta^\prime$ and $\eta(1410)$ is re-investigated based on
the modified Kawai model. The glueball-quarkonia content of the three states is
determined from a fit to the data of the electromagnetic decays involving
$\eta$, $\eta^\prime$. Some predictions about the electromagnetic decays
involving $\eta(1410)$ are presented.

</DOC>
<DOC>
<DOCNO> 101219 </DOCNO>
Rational period functions on the Hecke groups


  We describe rational period functions on the Hecke groups and characterize
the ones whose poles satisfy a certain symmetry. This generalizes part of the
characterization of rational period functions on the modular group, which is
one of the Hecke groups.

</DOC>
<DOC>
<DOCNO> 7709 </DOCNO>
Paramagnetic Meissner effect in mesoscopic samples


  Using the non-linear Ginzburg-Landau (GL) theory, we study the magnetic
response of different shaped samples in the field-cooled regime (FC). For high
external magnetic fluxes, the conventional diamagnetic response under cooling
down can be followed by the paramagnetic Meissner effect (PME). A second-order
transition from a giant vortex state to a multi-vortex state, with the same
vorticity, occurs at the second critical field which leads to the suppression
of PME.

</DOC>
<DOC>
<DOCNO> 100798 </DOCNO>
Factorizing twists and the universal R-matrix of the Yangian Y(sl_2)


  We give an explicit construction of the factorizing twists for the Yangian
Y(sl_2) in evaluation representations (not necessarily finite-dimensional). The
result is a universal expression for the factorizing twist that holds in all
these representations. The method is general enough to recover the universal
R-matrix of Y(sl_2) up to its character in the form specialized to generic
evaluation representations. The method presented here is particularly amenable
to generalizations because it involves only elementary operations applied to
representations of the Yangian.

</DOC>
<DOC>
<DOCNO> 12680 </DOCNO>
Saddle point states and energy barriers for vortex entrance and exit in


  The transitions between the different vortex states of thin mesoscopic
superconducting disks and rings are studied using the non-linear
Ginzburg-Landau functional. They are saddle points of the free energy
representing the energy barrier which has to be overcome for transition between
the different vortex states. In small superconducting disks and rings the
saddle point state between two giant vortex states, and in larger systems the
saddle point state between a multivortex state and a giant vortex state and
between two multivortex states is obtained. The shape and the height of the
nucleation barrier is investigated for different disk and ring configurations.

</DOC>
<DOC>
<DOCNO> 84682 </DOCNO>
Isolated Horizons: Hamiltonian Evolution and the First Law


  A framework was recently introduced to generalize black hole mechanics by
replacing stationary event horizons with isolated horizons. That framework is
significantly extended. The extension is non-trivial in that not only do the
boundary conditions now allow the horizon to be distorted and rotating, but
also the subsequent analysis is based on several new ingredients. Specifically,
although the overall strategy is closely related to that in the previous work,
the dynamical variables, the action principle and the Hamiltonian framework are
all quite different. More importantly, in the non-rotating case, the first law
is shown to arise as a necessary and sufficient condition for the existence of
a consistent Hamiltonian evolution. Somewhat surprisingly, this consistency
condition in turn leads to new predictions even for static black holes. To
complement the previous work, the entire discussion is presented in terms of
tetrads and associated (real) Lorentz connections.

</DOC>
<DOC>
<DOCNO> 119262 </DOCNO>
The Spatial and Kinematic Distributions of Cluster Galaxies in a LCDM


  We combine dissipationless N-body simulations and semi-analytic models of
galaxy formation to study the spatial and kinematic distributions of cluster
galaxies in a LCDM cosmology. We investigate how the star formation rates,
colours and morphologies of galaxies vary as a function of distance from the
cluster centre and compare our results with the CNOC1 survey of galaxies from
15 X-ray luminous clusters in the redshift range 0.18 to 0.55. In our model,
gas no longer cools onto galaxies after they fall into the cluster and their
star formation rates decline on timescales of 1-2 Gyr. Galaxies in cluster
cores have lower star formation rates and redder colours than galaxies in the
outer regions because they were accreted earlier. Our colour and star formation
gradients agree with those those derived from the data. The difference in
velocity dispersions between red and blue galaxies observed in the CNOC1
clusters is also well reproduced by the model. We assume that the morphologies
of cluster galaxies are determined solely by their merging histories.
Morphology gradients in clusters arise naturally, with the fraction of bulge-
dominated galaxies highest in cluster cores. We compare these gradients with
the CNOC1 data and find excellent agreement for bulge-dominated galaxies. The
simulated clusters contain too few galaxies of intermediate bulge-to-disk
ratio, suggesting that additional processes may influence the morphological
evolution of disk-dominated galaxies in clusters. Although the properties of
the cluster galaxies in our model agree extremely well with the data, the same
is not true of field galaxies. Both the star formation rates and the colours of
bright field galaxies appear to evolve much more strongly from redshift 0.2 to
0.4 in the CNOC1 field sample than in our simulations.

</DOC>
<DOC>
<DOCNO> 83306 </DOCNO>
PushPush and Push-1 are NP-hard in 2D


  We prove that two pushing-blocks puzzles are intractable in 2D. One of our
constructions improves an earlier result that established intractability in 3D
[OS99] for a puzzle inspired by the game PushPush. The second construction
answers a question we raised in [DDO00] for a variant we call Push-1. Both
puzzles consist of unit square blocks on an integer lattice; all blocks are
movable. An agent may push blocks (but never pull them) in attempting to move
between given start and goal positions. In the PushPush version, the agent can
only push one block at a time, and moreover when a block is pushed it slides
the maximal extent of its free range. In the Push-1 version, the agent can only
push one block one square at a time, the minimal extent---one square. Both
NP-hardness proofs are by reduction from SAT, and rely on a common
construction.

</DOC>
<DOC>
<DOCNO> 151590 </DOCNO>
Four Dimensional Conformal Supergravity From AdS Space


  Exploring the role of conformal theories of gravity in string theory, we show
that the minimal (N=2) gauged supergravities in five dimensions induce the
multiplets and transformations of N=1 four dimensional conformal supergravity
on the spacetime boundary. N=1 Poincare supergravity can be induced by
explicitly breaking the conformal invariance via a radial cutoff in the 5d
space. The AdS/CFT correspondence relates the maximal gauged supergravity in
five dimensions to N=4 super Yang-Mills on the 4d spacetime boundary. In this
context we show that the conformal anomaly of the gauge theory induces
conformal gravity on the boundary of the space and that this theory, via the
renormalization group, encapsulates the gravitational dynamics of the skin of
asymptotically AdS spacetimes. Our results have several applications to the
AdS/CFT correspondence and the Randall-Sundrum scenario.

</DOC>
<DOC>
<DOCNO> 40637 </DOCNO>
Time Dependent B0s - B0s-bar Mixing Using Inclusive and Semileptonic B


  We set a preliminary 95% C.L. exclusion on the oscillation frequency of B0s -
B0s-bar mixing using a sample of 400,000 hadronic Z0 decays collected by the
SLD experiment at the SLC between 1996 and 1998. The analyses determine the
b-hadron flavor at production by exploiting the large forward-backward
asymmetry of polarized Z0 -> b b-bar decays as well as information from the
hemisphere opposite that of the reconstructed B decay. In one analysis, B decay
vertices are reconstructed inclusively with a topological technique,and
separation between B0s and B0s-bar decays exploits the B0s -> Ds- cascade
charge structure. In the other analysis, semileptonic decays are selected and
the B decay point is reconstructed by intersecting a lepton track with the
trajectory of a topologically reconstructed D meson. The two analyses are
combined with a third analysis described elsewhere to exclude the following
values of the B0s - B0s-bar mixing oscillation frequency: Delta m_s < 7.6 ps-1
and 11.8 < Delta m_s < 14.8 ps-1 at the 95% confidence level.

</DOC>
<DOC>
<DOCNO> 100064 </DOCNO>
Expansiveness of algebraic actions on connected groups


  We consider endomorphism actions of arbitrary discrete semigroups on a
connected metrizable topological group G. We give necessary and sufficient
conditions for expansiveness of such actions when G is a Lie group or a compact
finite-dimensional group.

</DOC>
<DOC>
<DOCNO> 11020 </DOCNO>
Interaction between directional epistasis and average mutational effects


  We investigate the relationship between the average fitness decay due to
single mutations and the strength of epistatic interactions in genetic
sequences. We observe that epistatic interactions between mutations are
correlated to the average fitness decay, both in RNA secondary structure
prediction as well as in digital organisms replicating in silico. This
correlation implies that during adaptation, epistasis and average mutational
effect cannot be optimized independently. In experiments with RNA sequences
evolving on a neutral network, the selective pressure to decrease the
mutational load then leads to a reduction of the amount of sequences with
strong antagonistic interactions between deleterious mutations in the
population.

</DOC>
<DOC>
<DOCNO> 116406 </DOCNO>
Ultrastable CO2 Laser Trapping of Lithium Fermions


  We demonstrate an ultrastable CO2 laser trap that provides tight confinement
of neutral atoms with negligible optical scattering and minimal laser-noise-
induced heating. Using this method, fermionic 6Li atoms are stored in a 0.4 mK
deep well with a 1/e trap lifetime of 300 sec, consistent with a background
pressure of 10^(-11) Torr. To our knowledge, this is the longest storage time
ever achieved with an all-optical trap, comparable to the best reported
magnetic traps.

</DOC>
<DOC>
<DOCNO> 122021 </DOCNO>
Hyper- and suspended-accretion states of rotating black holes and the


  We analyze the temporal evolution of accretion onto rotating black holes
subject to large-scale magnetic torques. Wind torques alone drive a disk
towards collapse in a finite time $\sim t_{ff} E_k/E_B$, where $t_{ff}$ is the
initial free-fall time and $E_k/E_B$ is the ratio of kinetic-to-poloidal
magnetic energy. Additional spin-up torques from a rapidly rotating black hole
can arrest the disk's inflow. We associate short/long gamma-ray bursts with
hyperaccretion/suspended-accretion onto slowly/rapidly spinning black holes.
This model predicts afterglow emission from short bursts, and may be tested by
HETE-II.

</DOC>
<DOC>
<DOCNO> 169792 </DOCNO>
Decoherence, Quantum Zeno Effect, and the Efficacy of Mental Effort


  Recent theoretical and experimental papers support the prevailing opinion
that large warm systems will rapidly lose quantum coherence, and that classical
properties will emerge. This rapid loss of coherence would naturally be
expected to block any critical role for quantum theory in explaining the
interaction between our conscious experiences and the physical activities of
our brains. However, there is a quantum theory of mind in which the efficacy of
mental effort is not affected by decoherence effects. In this theory the
effects of mental action on brain activity is achieved by a Quantum Zeno Effect
that is not weakened by decoherence. The theory is based on a relativistic
version of von Neumann's quantum theory. It encompasses all the predictions of
Copenhagen quantum theory, which include all the validated predictions of
classical physical theory. In addition, it forges two-way dynamical links
between the physical and experiential aspects of nature. The theory has
significant explanatory power.

</DOC>
<DOC>
<DOCNO> 100926 </DOCNO>
Local models in the ramified case I. The EL-case


  Local models are schemes defined in linear algebra terms that describe the
'etale local structure of integral models for Shimura varieties and other
moduli spaces. We point out that the flatness conjecture of Rapoport-Zink on
local models fails in the presence of ramification and that in that case one
has to modify their definition. We study in detail certain modifications of the
local models for G=R_{E/F}GL(n), with E/F a totally ramified extension, and for
a maximal parahoric level subgroup. The special fibers of these models are
subschemes of the affine Grassmannian. We show that the new local models are
smoothly equivalent to "rank varieties" of matrices, are flat, normal, with
rational singularities and that their special fibers contain the expected
Schubert strata. A corollary is that Schubert varieties in the affine
Grassmannian are smoothly equivalent to nilpotent orbit closures and are normal
with rational singularities, even in positive characteristics. We give some
applications to the calculation of sheaves of nearby cycles and describe a
relation with geometric convolution. Finally, in the general EL case, we
replace the flatness conjecture of Rapoport-Zink with a conjecture about the
modified local models.

</DOC>
<DOC>
<DOCNO> 122631 </DOCNO>
Disk-corona interactions in soft spectral states of black hole binaries


  Re-analysis of some archival X-ray data of black hole binaries in soft
spectral states is presented. Results of detailed spectral fitting, including
proper physical description of the X-ray reprocessed component, indicate that
in most cases the soft, thermal disk emission cannot be described by a simple
multi-color blackbody model. Additional Comptonization of those seed photons
provides an acceptable description of the soft component, implying a presence
of a warm (kT~1 keV), mildly optically thick (tau~10) phase of accreting
plasma.
   Combined spectral/temporal analysis of GS 1124-68 during 'flip-flop'
transitions in Very High State suggests that the optically thick accretion flow
can proceed in (at least) two modes giving the same time-integrated behaviour
(i.e. energy spectra) but very different timing behaviour.

</DOC>
<DOC>
<DOCNO> 102298 </DOCNO>
Clifford algebras obtained by twisting of group algebras


  We investigate the construction and properties of Clifford algebras by a
similar manner as our previous construction of the octonions, namely as a
twisting of group algebras of Z_2^n by a cocycle. Our approach is more general
than the usual one based on generators and relations. We obtain in particular
the periodicity properties and a new construction of spinors in terms of left
and right multiplication in the Clifford algebra.

</DOC>
<DOC>
<DOCNO> 8893 </DOCNO>
Optical transitions in broken gap heterostructures


  We have used an eight band model to investigate the electronic structures and
to calculate the optical matrix elements of InAs-GaSb broken gap semiconductor
heterostructures. The unusual hybridization of the conduction band states in
InAs layers with the valence band states in GaSb layers has been analyzed in
details. We have studied the dependence of optical matrix elements on the
degree of conduction-valence hybridization, the tuning of hybridization by
varying the width of the GaSb layers and/or InAs layers, and the sensitivity of
quantized levels to this tuning. Large spin-orbit splitting in energy bands has
been demonstrated. Our calculation can serve as a theoretical modeling for
infrared lasers based on broken gap quantum well heterostructures.

</DOC>
<DOC>
<DOCNO> 99790 </DOCNO>
Isogeny classes of abelian varieties with no principal polarizations


  We provide a simple method of constructing isogeny classes of abelian
varieties over certain fields k such that no variety in the isogeny class has a
principal polarization. In particular, given a field k, a Galois extension l of
k of odd prime degree p, and an elliptic curve E over k that has no complex
multiplication over k and that has no k-defined p-isogenies to another elliptic
curve, we construct a simple (p-1)-dimensional abelian variety X over k such
that every polarization of every abelian variety isogenous to X has degree
divisible by p^2. We note that for every odd prime p and every number field k,
there exist l and E as above. We also provide a general framework for
determining which finite group schemes occur as kernels of polarizations of
abelian varieties in a given isogeny class.
  Our construction was inspired by a similar construction of Silverberg and
Zarhin; their construction requires that the base field k have positive
characteristic and that there be a Galois extension of k with a certain
non-abelian Galois group.

</DOC>
<DOC>
<DOCNO> 9209 </DOCNO>
Exactness of the Annealed and the Replica Symmetric Approximations for


  We study a heteropolymer model with random contact interactions introduced
some time ago as a simplified model for proteins. The model consists of
self-avoiding walks on the simple cubic lattice, with contact interactions
between nearest neighbor pairs. For each pair, the interaction energy is an
independent Gaussian variable with mean value $B$ and variance $\D^2$. For this
model the annealed approximation is expected to become exact for low disorder,
at sufficiently high dimension and in the thermodynamic limit. We show that
corrections to the annealed approximation in the 3-d high temperature phase are
small, but do not vanish in the thermodynamic limit, and are in good agreement
with our replica symmetric calculations. Such corrections derive from the fact
that the overlap between two typical chains is nonzero. We explain why previous
authors had come to the opposite conclusion, and discuss consequences for the
thermodynamics of the model. Numerical results were obtained by simulating
chains up to length 1400 by means of the recent PERM algorithm, in the coil and
molten globular phases, well above the freezing temperature.

</DOC>
<DOC>
<DOCNO> 100996 </DOCNO>
A survey of noncommutative dynamical entropy


  The paper is a survey of dynamical entropy of automorphisms of operator
algebras. We describe the different entropies of Connes-Stormer,
 Connes-Narnhofer-Thirring, Sauvageot-Thouvenot, and Voiculescu, and discuss
the main examples of the theory.

</DOC>
<DOC>
<DOCNO> 12266 </DOCNO>
Proof of the thermodynamical stability of the E' center in SiO2


  The E' center is a paradigmatic radiation-induced defect in SiO2 whose
peculiar EPR and hyperfine activity has been known since over 40 years. This
center has been traditionally identified with a distorted, positively-charged
oxygen vacancy V_O+. However, no direct proof of the stability of this defect
has ever been provided, so that its identification is still strongly
incomplete. Here we prove directly that distorted V_O+ is metastable and that
it satisfies the key requirements for its identification as E', such as thermal
and optical response, and activation-deactivation mechanisms.

</DOC>
<DOC>
<DOCNO> 67634 </DOCNO>
Chiral-Odd Contribution to Single-Transverse Spin Asymmetry in Hadronic


  A formula for the single transverse spin asymmetry in the large-$p_T$ pion
production in the nucleon-nucleon collision is derived. We focuss on the
chiral-odd contribution where the transversity distribution and the chiral-odd
spin-independent twist-3 distribution contributes. This contribution is
expected to give rise to a large effect at $x_F\to -1$.

</DOC>
<DOC>
<DOCNO> 117101 </DOCNO>
Lamb Shift in Light Hydrogen-Like Atoms


  Calculation of higher-order two-loop corrections is now a limiting factor in
development of the bound state QED theory of the Lamb shift in the hydrogen
atom and in precision determination of the Rydberg constant. Progress in the
study of light hydrogen-like ions of helium and nitrogen can be helpful to
investigate these uncalculated terms experimentally. To do that it is necessary
to develop a theory of such ions. We present here a theoretical calculation for
low energy levels of helium and nitrogen ions.

</DOC>
<DOC>
<DOCNO> 71253 </DOCNO>
Diffractive Exclusive Photon Production in Deep Inelastic Scattering


  Predictions for deep Virtual Compton Scattering are obtained in a
two-component dipole model of diffraction. The model automatically includes
hard and soft components and implicitly allows for ``hadronic'' contributions
via large dipoles. It is also applicable to real Compton Scattering, which
provides an important constraint.

</DOC>
<DOC>
<DOCNO> 118885 </DOCNO>
Space-Based Infrared Near-Earth Asteroid Survey Simulation


  We demonstrate the efficiency and effectiveness of using a satellite-based
sensor with visual and infrared focal plane arrays to search for NEAs with
orbits largely interior to the Earth's orbit. Such a space-based system could
detect approximately 97% of the Atens and 64% of the, as yet hypothetical,
objects with orbits entirely Interior to Earth's Orbit with diameters greater
than 1 km in a five-year mission and obtain orbits, albedos and diameters for
all of them. These are the results of a feasibility study; optimizing the
concept presented would result in greater levels of completion. The cost of
such a space-based system is estimated to be within a factor of two of the cost
of a ground-based system capable of about 21st magnitude, which would provide
only orbits and absolute magnitudes and require decades to reach these
completeness levels. In addition to obtaining albedos and diameters for the
asteroids discovered in the space-based survey, a space-based system would
obtain the same information on virtually all known NEOs of interest. A combined
space-based and ground-based survey would be highly synergistic in that each
can concentrate on what it does best and each complements the strengths of the
other. An integrated ground-based and space-based system could accomplish the
Spaceguard goal in less time than the ground-based system alone. In addition,
the result would be a catalog containing well-determined orbits, diameters, and
albedos for the majority of NEAs with diameters greater than 500 m.

</DOC>
<DOC>
<DOCNO> 71780 </DOCNO>
D=4 Chiral String Compactifications from Intersecting Branes


  Intersecting Dp-branes often give rise to chiral fermions living on their
intersections. We study the construction of four-dimensional chiral gauge
theories by considering configurations of type II D(3+n)-branes wrapped on
non-trivial n-cycles on T^{2n} x(R^{2(3-n)}/Z_N), for n=1,2,3. The gauge
theories on the four non-compact dimensions of the brane world-volume are
generically chiral and non-supersymmetric. We analyze consistency conditions
(RR tadpole cancellation) for these models, and their relation to
four-dimensional anomaly cancellation. Cancellation of U(1) gauge anomalies
involves a Green-Schwarz mechanism mediated by RR partners of untwisted and/or
twisted moduli. This class of models is of potential phenomenological interest,
and we construct explicit examples of SU(3) x SU(2) x U(1) three-generation
models. The models are non-supersymmetric, but the string scale may be lowered
close to the weak scale so that the standard hierarchy problem is avoided. We
also comment on the presence of scalar tachyons and possible ways to avoid the
associated instabilities. We discuss the existence of (meta)stable
configurations of D-branes on 3-cycles in (T^2)^3, free of tachyons for certain
ranges of the six-torus moduli.

</DOC>
<DOC>
<DOCNO> 169853 </DOCNO>
Stochastic dynamics of electronic wave packets in fluctuating laser


  The dynamics of a laser-excited Rydberg electron under the influence of a
fluctuating laser field are investigated. Rate equations are developed which
describe these dynamics in the limit of large laser bandwidths for arbitrary
types of laser fluctuations. These equations apply whenever all coherent
effects have already been damped out. The range of validity of these rate
equations is investigated in detail for the case of phase fluctuations. The
resulting asymptotic power laws are investigated which characterize the long
time dynamics of the laser-excited Rydberg electron and it is shown to which
extent these power laws depend on details of the laser spectrum.

</DOC>
<DOC>
<DOCNO> 116799 </DOCNO>
Formation of Structure in Snowfields: Penitentes, Suncups, and Dirt


  Penitentes and suncups are structures formed as snow melts, typically high in
the mountains. When the snow is dirty, dirt cones and other structures can form
instead. Building on previous field observations and experiments, this work
presents a theory of ablation morphologies, and the role of surface dirt in
determining the structures formed. The glaciological literature indicates that
sunlight, heating from air, and dirt all play a role in the formation of
structure on an ablating snow surface. The present work formulates a
mathematical model for the formation of ablation morphologies as a function of
measurable parameters. The dependence of ablation morphologies on weather
conditions and initial dirt thickness are studied, focusing on the initial
growth of perturbations away from a flat surface. We derive a single-parameter
expression for the melting rate as a function of dirt thickness, which agrees
well with a set of measurements by Driedger. An interesting result is the
prediction of a dirt-induced travelling instability for a range of parameters.

</DOC>
<DOC>
<DOCNO> 102792 </DOCNO>
Invitation to higher local fields, Part II, section 8: Higher local skew


  This work studies two dimensional local skew fields and their automorphisms.

</DOC>
<DOC>
<DOCNO> 152258 </DOCNO>
Chern-Simons Hadronic Bag from Quenched Large-N QCD


  SU(N) reduced, quenched, gauge theories have been shown to be related to
string theories. We extend this result and show how a 4-dimensional, reduced,
quenched, Yang-Mills theory, supplemented by the topological term, can be
related through the Wigner-Weyl-Moyal correspondence to an open 3-brane model.
The boundary of the 3-brane is described by a Chern-Simons 2-brane. We identify
the bulk of the 3-brane with the interior of a hadronic bag and the
world-volume of the Chern-Simons 2-brane with the dynamical boundary of the
bag. We estimate the value of the induced bag constant to be a little less than
200MeV.

</DOC>
<DOC>
<DOCNO> 68608 </DOCNO>
Glueball Spectrum for QCD from AdS Supergravity Duality


  We present the analysis of the complete glueball spectrum for the $AdS^7$
black hole supergravity dual of $QCD_4$ in strong coupling limit: $g^2 N \to
\infty$. The bosonic fields in the supergravity multiplet lead to 6 independent
wave equations contributing to glueball states with $J^{PC} = 2^{++},1^{+-},
1^{--}$, $0^{++}$ and $0^{-+}$. We study the spectral splitting and degeneracy
patterns for both $QCD_4$ and $QCD_3$. Despite the expected limitations of a
leading order strong coupling approximation, the pattern of spins, parities and
mass inequalities bear a striking resemblance to the known $QCD_4$ glueball
spectrum as determined by lattice simulations at weak coupling.

</DOC>
<DOC>
<DOCNO> 100366 </DOCNO>
Nef divisors in codimension one on the moduli space of stable curves


  Let M_g be the moduli space of smooth curves of genus g >= 3, and \bar{M}_g
the Deligne-Mumford compactification in terms of stable curves. Let
\bar{M}_g^{[1]} be an open set of \bar{M}_g consisting of stable curves of
genus g with one node at most. In this paper, we determine the necessary and
sufficient condition to guarantee that a Q-divisor D on \bar{M}_g is nef over
\bar{M}_g^{[1]}, that is, (D . C) >= 0 for all irreducible curves C on
\bar{M}_g with C \cap \bar{M}_g^{[1]} \not= \emptyset.

</DOC>
<DOC>
<DOCNO> 152484 </DOCNO>
Some Problems Concerning Interchange of Order of Integration in


  We show that in the functional integral formalism of U(1) gauge field theory
some formal manipulation such as interchange of order of integration can yield
erroneous results. The example studied is analysed by Fubini theorem.

</DOC>
<DOC>
<DOCNO> 119944 </DOCNO>
Spatial and Energy Distribution of Muons in Gamma-induced Air Showers


  The FLUKA Monte Carlo program is used to calculate the effects of
hadroproduction by primary gamma rays incident upon the earth's atmosphere; for
the results presented in this paper, only primary angles at 0 degrees from
zenith are considered. The FLUKA code is believed to be quite accurate in
reproducing experimental photon hadroproduction data in the 1 GeV to 10 TeV
energy range studied. The charged pions which are so produced can decay to
muons with sufficient energy to reach ground level. The number of these muons
and their radial and energy distribution are studied for incident gamma ray
energies from 1 GeV to 10 TeV. The number of these muons is not negligible;
they can, in certain circumstances, be used to study potential sources of gamma
rays like gamma ray bursts. It is found, for example, that a 10 TeV incident
primary gamma ray produces, on average, 3.4 muons which reach ground level; the
gamma ray energy which produces the maximum number of muons at ground level
depends on the spectral index of the primary gamma spectrum, a constant which
describes how the primary gamma flux rises with decreasing primary energy. An
example: for a differential spectral index of 2.7, there is a broad maximum
number of muons coming from ~ 30 GeV primary gamma ray energy.

</DOC>
<DOC>
<DOCNO> 122939 </DOCNO>
Multi-electron SEFs for nuclear reactions involved in advanced stages of


  Multi-electron screening effects encountered in laboratory astrophysical
reactions are investigated by considering the reactants Thomas-Fermi atoms. By
means of that model, previous studies are extended to derive the corresponding
screening enhancement factor (SEF), so that it takes into account ionization,
thermal, exchange and relativistic effects. The present study, by imposing a
very satisfactory constraint on the possible values of the screening energies
and the respective SEFs, corrects the current (and the future) experimental
values of the astrophysical factors associated with nuclear reactions involved
in advanced stages of stellar evolution.

</DOC>
<DOC>
<DOCNO> 178393 </DOCNO>
Sensitivities of the Proton-Nucleus Elastical Scattering Observables of


  We investigate the use of proton-nucleus elastic scattering experiments using
secondary beams of 6He and 8He to determine the physical structure of these
nuclei. The sensitivity of these experiments to nuclear structure is examined
by using four different nuclear structure models with different spatial
features using a full-folding optical potential model. The results show that
elastic scattering at intermediate energies (<100 MeV per nucleon) is not a
good constraint to be used to determine features of structure. Therefore
researchers should look elsewhere to put constraints on the ground state wave
function of the 6He and 8He nuclei.

</DOC>
<DOC>
<DOCNO> 102732 </DOCNO>
A proof of the Baum-Connes conjecture for reductive adelic groups


  Let F be a global field, A its ring of adeles, G a reductive group over F. We
prove the Baum-Connes conjecture for the adelic group G(A).

</DOC>
<DOC>
<DOCNO> 169950 </DOCNO>
Preparation of GHZ states via Grover's quantum searching algorithm


  In this paper we propose an approach to prepare GHZ states of an arbitrary
multi-particle system in terms of Grover's fast quantum searching algorithm.
 This approach can be regarded as an extension of the Grover's algorithm to
find one or more items in an unsorted database.

</DOC>
<DOC>
<DOCNO> 118508 </DOCNO>
The Enigmatic Radio Afterglow of GRB 991216


  We present wide-band radio observations spanning from 1.4 GHz to 350 GHz of
the afterglow of GRB 991216, taken from 1 to 80 days after the burst. The
optical and X-ray afterglow of this burst were fairly typical and are explained
by a jet fireball. In contrast, the radio light curve is unusual in two
respects: (a) the radio light curve does not show the usual rise to maximum
flux on timescales of weeks and instead appears to be declining already on day
1 and (b) the power law indices show significant steepening from the radio
through the X-ray bands. We show that the standard fireball model, in which the
afterglow is from a forward shock, is unable to account for (b) and we conclude
that the bulk of the radio emission must arise from a different source. We
consider two models, neither of which can be ruled out with the existing data.
In the first (conventional) model, the early radio emission is attributed to
emission from the reverse shock as in the case of GRB 990123. We predict that
the prompt optical emission would have been as bright (or brighter) than 8th
magnitude. In the second (exotic) model, the radio emission originates from the
forward shock of an isotropically energetic fireball (10^54 erg) expanding into
a tenuous medium (10^-4 cm^-3). The resulting fireball would remain
relativistic for months and is potentially resolvable with VLBI techniques.
Finally, we note that the near-IR bump of the afterglow is similar to that seen
in GRB 971214 and no fireball model can explain this bump.

</DOC>
<DOC>
<DOCNO> 13098 </DOCNO>
Detection of non separable correlations with dc transport: a new type of


  I construct a minimal formalism to describe transport of non separable
correlations arising when a superconductor is in contact with several
electrodes (being ferromagnetic or normal metal). Transport theory is expressed
in terms of effective single site Green's functions. Part of the circuit is
decimated exactly by renormalizing only one physical parameter (the density of
states). I show that the physical current is obtained by acting on the infinite
series of Feynman diagrams with an operator counting the charge of a given
diagram. I use this method to propose a new Aharonov-Bohm experiment intended
to detect non separable correlations. In this experiment, spin-$\sigma$
electrons are forced to travel around an Aharonov-Bohm loop in the presence of
an applied magnetic flux, while spin-($- \sigma$) electrons are not directly
coupled to the magnetic flux. It is shown that the spin-($-\sigma$) current
oscillates as a function of the flux to which spin-$\sigma$ electrons are
coupled. It is predicted that the effect exists both with high and low
transparency contacts, and that the electrodes can be normal metal in which
phase coherence can propagate over large distances. Three other aspects of the
problem are investigated: (i) The dependence of the superconducting gap on spin
polarization of ferromagnetic electrodes connected to the superconductor; (ii)
The detection of linear superposition of correlated pairs of electrons; (iii)
The proximity effect version of cryptomagnetism.

</DOC>
<DOC>
<DOCNO> 169955 </DOCNO>
Nonbinary Quantum Stabilizer Codes


  We define and show how to construct nonbinary quantum stabilizer codes. Our
approach is based on nonbinary error bases. It generalizes the relationship
between selforthogonal codes over $GF_{4}$ and binary quantum codes to one
between selforthogonal codes over $GF_{q^2}$ and $q$-ary quantum codes for any
prime power $q$.

</DOC>
<DOC>
<DOCNO> 102559 </DOCNO>
Simplicial and categorical comma categories


  We consider four categories: the category of diagrams of small categories
indexed by a given small category O, the (comma) category of small categories
over O, the category of diagrams of simplicial sets indexed by O, and the
category of simplicial sets over the nerve of O. Fritsch and Golasinski claimed
that these four categories have equivalent homotopy categories but, in fact,
their proof contains an error and the homotopy categories are not equivalent
with the weak equivalences they use in the comma categories. We show here that
the correct weak equivalences are the ``weak fibre homotopy equivalences''
defined by Latch. We also construct a model category structure on the category
of simplicial sets over NO in which the weak equivalences are the weak fibre
homotopy equivalences.

</DOC>
<DOC>
<DOCNO> 100639 </DOCNO>
Prym varieties and the canonical map of surfaces of general type


  Let X be a smooth complex surface of general type such that the image of the
canonical map $\phi$ of X is a surface $\Sigma$ and that $\phi$ has degree
$\delta\geq 2$. Let $\epsilon\colon S\to \Sigma$ be a desingularization of
$\Sigma$ and assume that the geometric genus of S is not zero. Beauville has
proved that in this case S is of general type and $\epsilon$ is the canonical
map of S. Beauville has also constructed the only infinite series of examples
$\phi:X\to \Sigma$ with the above properties that was known up to now. Starting
from his construction, we define a {\em good generating pair}, namely a pair
$(h:V\to W, L)$ where h is a finite morphism of surfaces and L is a nef and big
line bundle of W satisfying certain assumptions. We show that by applying a
construction analogous to Beauville's to a good generating pair one obtains an
infinite series of surfaces of general type whose canonical map is 2-to-1 onto
a canonically embedded surface. In this way we are able to construct more
infinite series of such surfaces. In addition, we show that good generating
pairs have bounded invariants and that there exist essentially only 2 examples
with $\dim |L|>1$. The key fact that we exploit for obtaining these results is
that the Albanese variety P of V is a Prym variety and that the fibre of the
Prym map over P has positive dimension.

</DOC>
<DOC>
<DOCNO> 10877 </DOCNO>
Note on the magnetotransport in the normal state of high-Tc cuprates


  Theories of the magnetotransport, based on the quasipartricle of the
Fermi-liquid, in the normal state of high-Tc cuprate superconductors, are
critically examined and the necessity of the collective transport theory beyond
the quasiparticle is discussed.

</DOC>
<DOC>
<DOCNO> 120882 </DOCNO>
Relativistic Viscous Fluid Description of Microscopic Black Hole Wind


  Microscopic black holes explode with their temperature varying inversely as
their mass. Such explosions would lead to the highest temperatures in the
present universe, all the way to the Planck energy. Whether or not a
quasi-stationary shell of matter undergoing radial hydrodynamic expansion
surrounds such black holes is been controversial. In this paper relativistic
viscous fluid equations are applied to the problem. It is shown that a
self-consistent picture emerges of a fluid just marginally kept in local
thermal equilibrium; viscosity is a crucial element of the dynamics.

</DOC>
<DOC>
<DOCNO> 9653 </DOCNO>
Kondo spin liquid and magnetically long-range ordered states in the


  A simplified version of the symmetric Kondo lattice model, the Kondo necklace
model, is studied by using a representation of impurity and conduction electron
spins in terms of local Kondo singlet and triplet operators. Within a mean
field theory, a spin gap always appears in the spin triplet excitation spectrum
in 1D, leading to a Kondo spin liquid state for any finite values of coupling
strength $t/J$ (with $t$ as hopping and $J$ as exchange); in 2D and 3D cubic
lattices the spin gaps are found to vanish continuously around $(t/J)_c\approx
0.70$ and $(t/J)_c\approx 0.38$, respectively, where quantum phase transitions
occur and the Kondo spin liquid state changes into an antiferromagnetically
long-range ordered state. These results are in agreement with variational Monte
Carlo, higher-order series expansion, and recent quantum Monte Carlo
calculations for the symmetric Kondo lattice model

</DOC>
<DOC>
<DOCNO> 84289 </DOCNO>
Open universes and avoidance of the cosmological singularity


  In the present paper we give conclusive arguments pointing at physical
equivalence among conformally related metrics. Based on the argument that any
consistent effective theory of spacetime must be invariant under the
one-parameter group of transformations of the units of length, time and
reciprocal mass, it is shown, also, that canonical general relativity is not
such a consistent theory. Conformal general relativity provides a consistent
formulation of the laws of gravity instead. We further extend the results of
papers gr-qc/9908075 and gr-qc/9905071 to open universes by studying the
Raychaudhuri equation.

</DOC>
<DOC>
<DOCNO> 152226 </DOCNO>
A Brief History of the Stringy Instanton


  The arcane ADHM construction of Yang-Mills instantons can be very naturally
understood in the framework of D-brane dynamics in string theory. In this
point-of-view, the mysterious auxiliary symmetry of the ADHM construction
arises as a gauge symmetry and the instantons are modified at short distances
where string effects become important. By decoupling the stringy effects, one
can recover all the instanton formalism, including the all-important volume
form on the instanton moduli space. We describe applications of the instanton
calculus to the AdS/CFT correspondence and higher derivative terms in the
D3-brane effective action. In these applications, there is an interesting
relation between instanton partition functions, the Euler characteristic of
instanton moduli space and modular symmetry. We also describe how it is now
possible to do multi-instanton calculations in gauge theory and we resolve an
old puzzle involving the gluino condensate in supersymmetric QCD.

</DOC>
<DOC>
<DOCNO> 120768 </DOCNO>
ISO observations of the planetary nebula Lindsay 305 in the Small


  We present ISO (Infrared Space Observatory) observations of the planetary
nebula Lindsay 305 (L 305) in the Small Magellanic Cloud. L 305 is very
prominent in the ISOCAM frames at 6.75 and 11.5 $\mu$m, although it is under
the detection limit at 4.5 $\mu$m. The obtained spectral energy distribution
shows a strong mid-IR excess, which, depending on the amount of energy radiated
at wavelengths longer than 11.5 $\mu$m, may be as large as $\sim 1500
L_{\odot}$. However, since an accurate estimate of the total nebular luminosity
is not available up to date, the evolutionary status of L 305 can not yet be
constrained precisely.

</DOC>
<DOC>
<DOCNO> 118021 </DOCNO>
The hard X-ray emission of luminous infrared galaxies


  We present a study of the hard X-ray properties of a sample that includes all
the Luminous Infrared Galaxies (LIGs, L_IR > 10^11 L_sun) observed in the 2-10
keV energy band (new and archival data). We find that a significant fraction of
the sources optically classified as AGNs do not show any indication of nuclear
activity in the X rays, thus suggesting heavy absorption along our line of
sight. The absence of strong emission in the 20-200 keV band in a subsample of
LIGs observed with BeppoSAX suggests that in many cases these sources are
completely Compton thick (N_H > 10^25 cm^(-2)). From a comparison between the
infrared and the X-ray emission we deduce that the mid-IR emission is absorbed
by a lower column density than the X-ray emission or, alternatively, that the
dust-to-gas ratio is lower than Galactic. We describe a simple model that
reproduces the IR-X correlation by means of mixed AGN and starburst
contributions and we compare the predictions of this model with the
observational data at X-ray and optical wavelengths. Finally, we discuss the
biases that affect the currently available samples of LIGs and briefly analyze
a small unbiased sample, finding that at least 50% of the sources host a (weak)
AGN.

</DOC>
<DOC>
<DOCNO> 69568 </DOCNO>
Proposal for a Very Forward Proton Spectrometer in H1 after 2000


  A new, very forward proton spectrometer (VFPS) with large acceptance is
proposed to be installed in the proton beam of the H1 experiment after the
luminosity upgrade in the year 2000. The spectrometer, located at 220 m
downstream of the interaction point is based on the Roman Pot technique and
consists of two stations situated in the cold section of the proton beam line.
Physics motivations and a brief description of the proton spectrometer are
presented.

</DOC>
<DOC>
<DOCNO> 12947 </DOCNO>
Doping induced spinless collective excitations of charge 2e in doped


  Based on the Hubbard model description of the doped Mott insulator, we prove
that there must exist a spinless collective excitation of charge $2e$ and of
energy $U-2\mu$ peaked at momentum $(\pi/a,\pi/a)$ in the non-superconducting
state due to doping. Such a collective excitation arises from the electron pair
correlation. Its existence is related to the breakdown of an approximate SU(2)
particle-hole symmetry, from which an effective field theory of the new
excitations is constructed.

</DOC>
<DOC>
<DOCNO> 120277 </DOCNO>
Daemon detection experiment


  A month-long observation of two horizontal ZnS(Ag) scintillating screens, 1
m^2 in area and located one above the other a certain distance apart, revealed
about 10 correlated signals, whose time shift corresponds to an average
velocity of only ~10-15 km/s. We assign the origin of these signals to the
negative daemons, i.e. electrically charged Planckian particles, which
supposedly form a part of the DM in the Galactic disk and were captured into
the near-Earth orbits. The estimated flux of daemons is >=10^-4 m^-2 s^-1. The
key part in the detection of daemons is played apparently by two processes: (i)
the daemon shedding the captured heavy nucleus in a few tens of mks as a result
of a relatively rapid decay of the daemon-containing nucleons, and (ii)
emission of numerous Auger electrons and nuclear particles occurring in the
next capture or recapture of a (heavier) nucleus by the daemon.

</DOC>
<DOC>
<DOCNO> 117189 </DOCNO>
Connection between the Dielectric and the Ballistic Treatment of


  In this work two important models of treating collisional absorption in a
laser driven plasma are compared, the dielectric and the ballistic model. We
will see that there exists a remarkable connection between these basic
approaches which could give a hint how to overcome the inherent limitations.
The approximations made in the models are not identical and lead to different
advantages and disadvantages. We notice that the dieletric model is able to
handle screening in a selfconsistent manner, but is limited to first order in
the electron-ion interaction. The ballistic model calculates the electron-ion
collision exactly in each order of the interaction, but has to introduce a
cut-off to incorporate screening effects. This means in the context of kinetic
theory that the electron-ion correlation has to be calculated either in random
phase or in ladder approximation, or, in other words, the linearized
Lenard-Balescu or Boltzmann collision term has to be used.

</DOC>
<DOC>
<DOCNO> 116261 </DOCNO>
Exact solution of the restricted three-body Santilli-Shillady model of


  In this paper, we study the exact solution of the restricted isochemical
model of $H_2$ molecule with fixed nuclei recently proposed by Santilli and
Shillady in which the two electrons are assumed to be bonded/correlated into a
quasiparticle called the {\it isoelectronium}. Under the conditions that: 1)
the isoelectronium is stable; 2) the effective size of the isoelectronium is
ignorable, in comparison to internuclear distance; and 3) the two nuclei are at
rest, the Santilli-Shillady model of the $H_2$ molecule is reduced to a
restricted {\it three-body} system essentially similar to a neutral version of
the $H_2^+$ ion, which, as such, admits exact solution. Our main result is that
the restricted three-body Santilli-Shillady approach to $H_2$ is capable to fit
the experimental binding energy, at the isoelectronium mass parameter
$M=0.308381m_e$, although under optimal internuclear distance about 19.6%
bigger than the conventional experimental value, indicating an approximate
character of the three-body model.

</DOC>
<DOC>
<DOCNO> 69190 </DOCNO>
Cosmological Gravitino Problem in Gauge-Mediated Supersymmetry Breaking


  We investigate the cosmological gravitino problem in gauge-mediated
supersymmetry breaking models, where the gravitino becomes in general the
lightest supersymmetric particle (LSP). In order to avoid the overclosure of
the stable gravitino, the reheating temperature of inflation $T_R$ should be
low enough. Furthermore, if the gravitino mass is larger than about 100 MeV,
the decay of the next-to-LSP (NLSP) into the gravitino may modify disastrously
the abundances of the light elements predicted by the big-bang nucleosynthesis
(BBN). We consider the case in which the lighter stau is the NLSP and derive
cosmological constraints from the BBN on the stau NLSP decay. We obtain a lower
bound on the mass of stau $m_{\staul}$, which is more stringent than the
current experimental limit $m_{\staul} > 90$ GeV for the gravitino mass region
$m_{3/2} \gsim 5$ GeV. This lower bound, together with the overclosure
constraint on the stable gravitino, gives an upper bound on $T_{R}$. We find
that the reheating temperature can be as high as $10^9$--$10^{10}$ GeV for
$m_{3/2} \simeq 5$--100 GeV.

</DOC>
<DOC>
<DOCNO> 170450 </DOCNO>
Iterative algorithm for reconstruction of entangled states


  An iterative algorithm for the reconstruction of an unknown quantum state
from the results of incompatible measurements is proposed. It consists of
Expectation-Maximization step followed by a unitary transformation of the
eigenbasis of the density matrix. The procedure has been applied to the
reconstruction of the entangled pair of photons.

</DOC>
<DOC>
<DOCNO> 72069 </DOCNO>
Comment on `Charged Particle Ratio Fluctuation as a Signal for


  Charge fluctuations studied on event-by-event basis have been recently
suggested to provide a signal of the equilibrium quark-gluon plasma produced in
heavy-ion collisions at high energies. It is argued that the fluctuations
generated at the early collision stage when the energy is released can fake the
signal.

</DOC>
<DOC>
<DOCNO> 8284 </DOCNO>
Modifications of the hydrogen bond network of liquid water in a


  We present results of molecular dynamics simulations of water confined in a
silica pore. A cylindrical cavity is created inside a vitreous silica cell with
geometry and size similar to the pores of real Vycor glass. The simulations are
performed at different hydration levels. At all hydration levels water adsorbs
strongly on the Vycor surface; a double layer structure is evident at higher
hydrations. At almost full hydration the modifications of the
confinement-induced site-site pair distribution functions are in qualitative
agreement with neutron diffraction experiment. A decrease in the number of
hydrogen bonds between water molecules is observed along the pore radius, due
to the tendency of the molecules close to the substrate to form hydrogen-bonds
with the hydrophilic pore surface. As a consequence we observe a substrate
induced distortion of the H-bond tetrahedral network of water molecules in the
regions close to the surface.

</DOC>
<DOC>
<DOCNO> 169885 </DOCNO>
Group Theoretical Quantum Tomography


  The paper is devoted to the mathematical foundation of the quantum tomography
using the theory of square-integrable representations of unimodular Lie groups.

</DOC>
<DOC>
<DOCNO> 11232 </DOCNO>
Turbulence for (and by) amateurs


  Series of lectures on statistical turbulence written for amateurs but not
experts. Elementary aspects and problems of turbulence in two and three
dimensional Navier-Stokes equation are introduced. A few properties of scalar
turbulence and transport phenomena in turbulent flows are described.
Kraichnan's model of passive advection is discussed a bit more precisely.
  {Part 1: Approaching turbulent flows.} Navier-Stokes equation. Cascades and
Kolmogorov theory. Modeling statistical turbulence. Correlation functions and
scaling.
  {Part 2: Deeper in turbulent flows.} Turbulence in two dimensions.
Dissipation and dissipative anomalies. Fokker-Planck equations. Multifractal
models.
  {Part 3: Scalar turbulence.} Transport and Lagrangian trajectories.
Kraichnan's passive scalar model. Anomalous scalings and universality.
  {Part 4: Lagrangian trajectories.} Richardson's law. Lagrangian flows in
Kraichnan's model. Slow modes. Breakdown of Lagrangian flows. Batchelor limit.
Generalized Lagrangian flows and trajectory bundles.

</DOC>
<DOC>
<DOCNO> 116493 </DOCNO>
What are the Hidden Quantum Processes In Einstein's Weak Principle of


  We provide a quantum derivation of Einstein's Weak Equivalence Principle
(WEP) of general relativity using a new quantum gravity theory proposed by the
authors called Electro-Magnetic Quantum Gravity or EMQG (ref. 1). Newtonian
Inertia is a property of matter due to the strictly local electrical force
interactions contributed by each of the (electrically charged) elementary
particles of the mass with the surrounding (electrically charged) virtual
particles (virtual masseons) of the quantum vacuum. The sum of all the tiny
electrical forces (photon exchanges with the vacuum particles) originating in
each charged elementary particle of the accelerated mass is the source of the
total inertial force of a mass which opposes accelerated motion in Newton's law
'F = MA'. We found that gravity also involves the same 'inertial'
electromagnetic force component that exists in inertial mass. We propose that
Einstein's general relativistic Weak Equivalence Principle (WEP) originates
from common 'lower level' quantum vacuum processes occurring in both inertial
mass and gravitational mass, in accordance with the principles of quantum field
theory. Gravitational mass results from the quantum activities of both the
electrical force (photon exchanges) component and the pure gravitational force
(graviton exchanges) component, acting simultaneously on the elementary
particles that make up a mass.

</DOC>
<DOC>
<DOCNO> 152588 </DOCNO>
Matrix model and noncommutative Chern-Simons theory


  In this short paper we would like to present a simple topological matrix
model which has close relation with the noncommutative Chern-Simons theory.

</DOC>
<DOC>
<DOCNO> 84971 </DOCNO>
Kinks, energy conditions and closed timelike curves


  A link between the possibility of extending a geodessically incomplete kinked
spacetime to a spacetime which is geodesically complete and the energy
conditions is discussed for the case of a cylindrically-symmetric spacetime
kink. It is concluded that neither the strong nor the weak energy condition can
be satisfied in the four-dimensional example, though the latter condition may
survive on the transversal sections of such a spacetime. It is also shown that
the matter which propagates quantum-mechanically in a kinked spacetime can
always be trapped by closed timelike curves, but signaling connections between
that matter and any possible observer can only be made of totally incoherent
radiation, so preventing observation of causality violation.

</DOC>
<DOC>
<DOCNO> 9010 </DOCNO>
Effect of boundary conditions on diffusion in two-dimensional granular


  We analyze the influence of boundary conditions on numerical simulations of
the diffusive properties of a two dimensional granular gas. We show in
particular that periodic boundary conditions introduce unphysical correlations
in time which cause the coefficient of diffusion to be strongly dependent on
the system size. On the other hand, in large enough systems with hard walls at
the boundaries, diffusion is found to be independent of the system size. We
compare the results obtained in this case with Langevin theory for an elastic
gas. Good agreement is found. We then calculate the relaxation time and the
influence of the mass for a particle of radius $R_s$ in a sea of particles of
radius $R_b$. As granular gases are dissipative, we also study the influence of
an external random force on the diffusion process in a forced dissipative
system. In particular, we analyze differences in the mean square velocity and
displacement between the elastic and inelastic cases.

</DOC>
<DOC>
<DOCNO> 100467 </DOCNO>
The non-dynamical r-matrices of the degenerate Calogero-Moser models


  A complete description of the non-dynamical r-matrices of the degenerate
Calogero-Moser models based on $gl_n$ is presented. First the most general
momentum independent r-matrices are given for the standard Lax representation
of these systems and those r-matrices whose coordinate dependence can be gauged
away are selected. Then the constant r-matrices resulting from gauge
transformation are determined and are related to well-known r-matrices. In the
hyperbolic/trigonometric case a non-dynamical r-matrix equivalent to a
real/imaginary multiple of the Cremmer-Gervais classical r-matrix is found. In
the rational case the constant r-matrix corresponds to the antisymmetric
solution of the classical Yang-Baxter equation associated with the Frobenius
subalgebra of $gl_n$ consisting of the matrices with vanishing last row. These
claims are consistent with previous results of Hasegawa and others, which imply
that Belavin's elliptic r-matrix and its degenerations appear in the
Calogero-Moser models. The advantages of our analysis are that it is elementary
and also clarifies the extent to which the constant r-matrix is unique in the
degenerate cases.

</DOC>
<DOC>
<DOCNO> 117113 </DOCNO>
On resistive magnetohydrodynamic equilibria of an axisymmetric toroidal


  It is shown that the magnetohydrodynamic equilibrium states of an
axisymmetric toroidal plasma with finite resistivity and flows parallel to the
magnetic field are governed by a second-order partial differential equation for
the poloidal magnetic flux function $\psi$ coupled with a Bernoulli type
equation for the plasma density (which are identical in form to the
corresponding ideal MHD equilibrium equations) along with the relation
$\Delta^\star \psi=V_c \sigma$. (Here, $\Delta^\star$ is the
Grad-Schl\"{u}ter-Shafranov operator, $\sigma$ is the conductivity and $V_c$ is
the constant toroidal-loop voltage divided by $2 \pi $). In particular, for
incompressible flows the above mentioned partial differential equation becomes
elliptic and decouples from the Bernoulli equation [H. Tasso and G. N.
Throumoulopoulos, Phys. Plasmas {\bf 5}, 2378 (1998)]. For a conductivity of
the form $\sigma=\sigma(R, \psi)$ ($R$ is the distance from the axis of
symmetry) several classes of analytic equilibria with incompressible flows can
be constructed having qualitatively plausible $\sigma$ profiles, i.e. profiles
with $\sigma$ taking a maximum value close to the magnetic axis and a minimum
value on the plasma surface. For $\sigma=\sigma(\psi)$ consideration of the
relation $\Delta^\star\psi = V_c \sigma(\psi)$ in the vicinity of the magnetic
axis leads therein to a proof of the non-existence of either compressible or
incompressible equilibria. This result can be extended to the more general case
of non-parallel flows lying within the magnetic surfaces.

</DOC>
<DOC>
<DOCNO> 122914 </DOCNO>
The Core-Wing Anomaly of Cool Ap Stars: Abnormal Balmer Profiles


  Paper by Cowley et al. The Core-Wing Anomaly Etc. The profiles of H$\alpha$
in a number of cool Ap stars are anomalous. Broad wings, indicative of
temperatures in the range 7000-8000K end abruptly in narrow cores. The widths
of these cores are compatible with those of dwarfs with temperatures of 6000K
or lower. This profile has been known for Przybylski's star, but it is seen in
other cool Ap's. The H$\beta$ profile in several of these stars shows a similar
core-wing anomaly (CWA). In Przybylski's star, the CWA is probably present at
higher Balmer members. We are unable to account for these profiles within the
context of LTE and normal dwarf atmospheres. We conclude that the atmospheres
of these stars are not ``normal.'' This is contrary to a notion that has long
been held.

</DOC>
<DOC>
<DOCNO> 12147 </DOCNO>
Generalizations of statistical mechanics on the basis of an incomplete


  Statistical mechanics is generalized on the basis of an incomplete
information theory with a new parameterized normalization leading to two
generalized statistical entropies : an extensive one and a nonextensive one.
The idea of incomplete probability distribution due to neglected interactions
or correlations allows to related the introduced parameter to the partition
function of unknown states and to the neglected interactions in physical
systems. Applications of these incomplete statistics to thermodynamics problems
and to some classical models of physical systems are discussed.

</DOC>
<DOC>
<DOCNO> 169865 </DOCNO>
Entanglement transformation at absorbing and amplifying four-port


  Dielectric four-port devices play an important role in optical quantum
information processing. Since for causality reasons the permittivity is a
complex function of frequency, dielectrics are typical examples of noisy
quantum channels, which cannot preserve quantum coherence. To study the effects
of quantum decoherence, we start from the quantized electromagnetic field in an
arbitrary Kramers--Kronig dielectric of given complex permittivity and
construct the transformation relating the output quantum state to the input
quantum state, without placing restrictions on the frequency. We apply the
formalism to some typical examples in quantum communication. In particular we
show that for entangled qubits the Bell-basis states $|\Psi^\pm>$ are more
robust against decoherence than the states $|\Phi^\pm>$.

</DOC>
<DOC>
<DOCNO> 80992 </DOCNO>
Accelerating the Hybrid Monte Carlo algorithm with ILU preconditioning


  The pseudofermion action of the Hybrid Monte Carlo (HMC) algorithm for
dynamical fermions is modified to directly incorporate Incomplete LU (ILU)
factorisation. This reduces the stochastic noise and allows a larger molecular
dynamics step-size to be taken, cutting the computational cost. Numerical tests
using the two-flavour Schwinger model are presented, where a two-step ILU
preconditioning of the even-odd fermion matrix allows the step-size to be
increased by a factor of two over the standard even-odd formulation.

</DOC>
<DOC>
<DOCNO> 122783 </DOCNO>
A New Radio - X-Ray Probe of Galaxy Cluster Magnetic Fields


  Results are presented of a new VLA-ROSAT study that probes the magnetic field
strength and distribution over a sample of 16 ``normal'' low redshift (z < 0.1)
galaxy clusters. The clusters span two orders of magnitude in X-ray luminosity,
and were selected to be free of (unusual) strong radio cluster halos, and
widespread cooling flows. Consistent with these criteria, most clusters show a
relaxed X-ray morphology and little or no evidence for recent merger activity.
  Analysis of the rotation measure (RM) data shows cluster-generated Faraday RM
excess out to ~0.5 Mpc from cluster centers. The results, combined with RM
imaging of cluster-embedded sources and ROSAT X-ray profiles indicates that the
hot intergalactic gas within these ``normal'' clusters is permeated with a high
filling factor by magnetic fields at levels of <|B|> = 5-10 (l/10 kpc)^{-1/2}
microGauss, where l is the field correlation length. These results lead to a
global estimate of the total magnetic energy in clusters, and give new insight
into the ultimate energy origin, which is likely gravitational. These results
also shed some light on the cluster evolutionary conditions that existed at the
onset of cooling flows.

</DOC>
<DOC>
<DOCNO> 116981 </DOCNO>
Review of Solid-State Modulators


  Solid-state modulators for pulsed power applications have been a goal since
the first fast high-power semiconductor devices became available. Recent
improvements in both the speed and peak power capabilities of semiconductor
devices developed for the power conditioning and traction industries have led
to a new generation of solid-state switched high power modulators with
performance rivaling that of hard tube modulators and thyratron switched
line-type modulators. These new solid-state devices offer the promise of higher
efficiency and longer lifetimes at a time when availability of standard
technologies is becoming questionable. A brief discussion of circuit topologies
and solid-state devices is followed by examples of modulators currently in use
or in test. This presentation is intended to give an overview of the current
capabilities of solid-state modulators in various applications.

</DOC>
<DOC>
<DOCNO> 151104 </DOCNO>
String Theory on AdS_3 as Discrete Light-Cone Liouville Theory


  We investigate (super) string theory on $AdS_3$ background based on an
approach of free field realization. We demonstrate that this string theory can
be reformulated as a string theory defined on a linear dilaton background along
the transverse direction (``Liouville mode'') and compactified onto $S^1$ along
a {\em light-like} direction.
  Under this reformulation we analyze the physical spectrum as that of a free
field system, and discuss the consequences when we turn on the Liouville
potential. The discrete light-cone momentum in our framework is naturally
interpreted as the ``winding number'' of the long string configuration and is
identified with the spectral flow parameter that is introduced in the recent
work by Maldacena and Ooguri \cite{MO}.
  Moreover we show that there exist infinite number of the on-shell chiral
primary states possessing the different light-cone momenta and the spectral
flow consistently acts on the space of chiral primaries. We observe that they
are also chiral primaries in the sense of space-time (or the conformal theory
of long string) and the spectrum of space-time $U(1)_R$ charge is consistent
with the expectation from the $AdS_3/CFT_2$-duality. We also clarify the
correspondence between our framework and the symmetric orbifold theory of
multiple long string system \cite{HS2}.

</DOC>
<DOC>
<DOCNO> 151666 </DOCNO>
Deformation quantization as the origin of D-brane non-Abelian degrees of


  I construct a map from the Grothendieck group of coherent sheaves to
$K$-homology. This results in explicit realizations of $K$-homology cycles
associated with D-brane configurations. Non-Abelian degrees of freedom arise in
this framework from the deformation quantization of $N$-tuple cycles. The large
$N$ limit of the gauge theory on D-branes wrapped on a subvariety $V$ of some
variety $X$ is geometrically interpreted as the deformation quantization of the
formal completion of $X$ along $V.$

</DOC>
<DOC>
<DOCNO> 69606 </DOCNO>
Inflationary solutions in the brane-world and their geometrical


  We consider the cosmology of a pair of domain walls bounding a
five-dimensional bulk space-time with negative cosmological constant, in which
the distance between the branes is not fixed in time. Although there are strong
arguments to suggest that this distance should be stabilized in the present
epoch, no such constraints exist for the early universe and thus non-static
solutions might provide relevant inflationary scenarios. We find the general
solution for the standard ansatz where the bulk is foliated by planar-symmetric
hypersurfaces. We show that in all cases the bulk geometry is that of anti-de
Sitter (AdS_5). We then present a geometrical interpretation for the solutions
as embeddings of two de Sitter (dS_4) surfaces in AdS_5, which provide a simple
interpretation of the physical properties of the solutions. A notable feature
explained in the analysis is that two-way communication between branes
expanding away from one another is possible for a finite amount of time, after
which communication can proceed in one direction only. The geometrical picture
also shows that our class of solutions (and related solutions in the
literature) are not completely general, contrary to some claims. We then derive
the most general solution for two walls in AdS_5. This includes novel
cosmologies where the brane tensions are not constrained to have opposite
signs. The construction naturally generalizes to arbitrary FRW cosmologies on
the branes.

</DOC>
<DOC>
<DOCNO> 67846 </DOCNO>
The Delta I = 1/2 Rule and epsilon'/epsilon in the Chiral Quark Model


  I discuss the role of the Delta I = 1/2 selection rule in K -> pi pi decays
for the theoretical calculations of eps'/eps. Lacking reliable ``first
principle'' calculations, phenomenological approaches may help in understanding
correlations among different contributions and available experimental data. In
particular, in the chiral quark model approach the same dynamics which
underlies the Delta I = 1/2 selection rule in kaon decays appears to enhance
the K -> pi pi matrix elements of the gluonic penguins, thus driving eps'/eps
in the range of the recent experimental measurements.

</DOC>
<DOC>
<DOCNO> 100200 </DOCNO>
Simple purely infinite C*-algebras and n-filling actions


  Let $n$ be a positive integer. We introduce a concept, which we call the
$n$-filling property, for an action of a group on a separable unital
$C^*$-algebra $A$. If $A=C(\Omega)$ is a commutative unital $C^*$-algebra and
the action is induced by a group of homeomorphisms of $\Omega$ then the
$n$-filling property reduces to a weak version of hyperbolicity. The
$n$-filling property is used to prove that certain crossed product
$C^*$-algebras are purely infinite and simple. A variety of group actions on
boundaries of symmetric spaces and buildings have the $n$-filling property. An
explicit example is the action of $\Gamma=SL_n({\bf Z})$ on the projective
$n$-space.

</DOC>
<DOC>
<DOCNO> 71325 </DOCNO>
Coherent QCD phenomena in the Coherent Pion-Nucleon and Pion-Nucleus


  We use QCD to compute the cross section for coherent production of a di-jet
(treated as a $q\bar q$ moving at high relative transverse momentum,$\kappa_t
$). In the target rest frame,the space-time evolution of this reaction is
dominated by the process in which the high $\kappa_t$ $q\bar q$ component of
the pion wave function is formed before reaching the target. It then interacts
through two gluon exchange. In the approximation of keeping the leading order
in powers of $\alpha_s$ and all orders in
$\alpha_{s}\ln(\kappa_{t}^2/k_{0}^2),$ the amplitudes for other processes are
shown to be smaller at least by a power of $\alpha_{s}$. The resulting dominant
amplitude is proportional to $z(1-z) \kappa_t^{-4}$ ($z$ is the fraction
light-cone(+)momentum carried by the quark in the final state) times the skewed
gluon distribution of the target. For the pion scattering by a nuclear target,
this means that at fixed $x_{N}= 2\kappa_{t}^2/s$ (but $\kappa_{t}^2\to
\infty$) the nuclear process in which there is only a single interaction is the
most important one to contribute to the reaction. Thus in this limit color
transparency phenomena should occur.These findings are in accord with E971
experiment at FNAL. We also re-examine a potentially important nuclear multiple
scattering correction which is positive and $\propto A^{1/3}/\kappa_t^4$. The
meaning of the signal obtained from the experimental measurement of pion
diffraction into two jets is also critically examined and significant
corrections are identified.We show also that for values of $\kappa_t$ achieved
at fixed target energies, di-jet production by the e.m. field of the nucleus
leads to an insignificant correction which gets more important as $\kappa_t$
increases.

</DOC>
<DOC>
<DOCNO> 118881 </DOCNO>
Central cusp due to a super-massive black hole in axisymmetric models of


  We use numerical simulations to investigate the cusp at the centre of
elliptical galaxies, due to the slow growth of a super-massive black hole. We
study this problem for axisymmetric models of galaxies, with or without
rotation. The numerical simulations are based on the `Perturbation Particles'
method, and use GRAPEs to compute the force due to the cusp. We study how the
density cusp is affected by the initial flattening of the model, as well as the
role played by initial rotation. The logarithmic slope of the density cusp is
found to be very much insensitive to flattening; as a consequence, we deduce
that tangential velocity anisotropy -which supports the flattening- is also of
little influence on the final cusp. We investigate via two different kinds of
rotating models the efficiency with which a rotation velocity component builds
within the cusp. A cusp in rotation develops only for models where a net
rotation component is initially present at high energy levels. The eventual
observation of a central rotational velocity peak in E galaxies has therefore
some implications for the galaxy dynamical history.

</DOC>
<DOC>
<DOCNO> 120335 </DOCNO>
Disk Galaxies and Galaxy Disks


  The conference Galaxy Disks and Disk Galaxies, sponsored by the Vatican
Observatory, was held in June 12-16, 2000 at the Pontifical Gregorian
University, in Rome (Italy). The meeting hosted about 230 participants coming
from 30 countries. The very full program consisted of 29 review papers, 34
invited talks, and more than 180 posters. The meeting covered topics regarding
the structure, formation and evolution of galaxies with disks. Particular
attention was dedicated to the stellar and gaseous disk of the Milky Way, the
global characteristics of galaxy disks, their structure, morphology and
dynamics, the gaseous components, star formation, and chemical evolution, the
interactions, accretion, mergers and starbursts, the dark and luminous matter,
the establishment of the scaling laws, and the formation and evolution of disk
galaxies from a theoretical and observational point of view.

</DOC>
<DOC>
<DOCNO> 8848 </DOCNO>
On the possibility to supercool molecular hydrogen down to superfluid


  Recent calculations by Vorobev and Malyshenko (JETP Letters, 71, 39, 2000)
show that molecular hydrogen may stay liquid and superfluid in strong electric
fields of the order of $4\times 10^7 V/cm$. I demonstrate that strong local
electric fields of similar magnitude exist beneath a two-dimensional layer of
electrons localized in the image potential above the surface of solid hydrogen.
Even stronger local fields exist around charged particles (ions or electrons)
if surface or bulk of a solid hydrogen crystal is statically charged.
Measurements of the frequency shift of the $1 \to 2$ photoresonance transition
in the spectrum of two-dimensional layer of electrons above positively or
negatively charged solid hydrogen surface performed in the temperature range 7
- 13.8 K support the prediction of electric field induced surface melting. The
range of surface charge density necessary to stabilize the liquid phase of
molecular hydrogen at the temperature of superfluid transition is estimated.

</DOC>
<DOC>
<DOCNO> 7624 </DOCNO>
Simple model for the linear temperature dependence of the electrical


  The thermal fluctuations of the electric field between the CuO_2 planes of
layered cuprates are considered as an origin of the electrical resistivity. The
model evaluation employs a set of separate plane capacitors each having area
equal to the squared in-plane lattice constant a_0^2. It is shown that the
scattering of charge carriers by the fluctuation of electric charge in the
conducting CuO_2 planes gives rise to the in-plane electrical resistivity
rho_ab. Such a mechanism can be viewed as an analog of the Rayleigh's blue-sky
law---the charge carriers are scattered by thermal fluctuations of electron
density.

</DOC>
<DOC>
<DOCNO> 118812 </DOCNO>
The quasar fraction in low-frequency selected complete samples and


  Low-frequency radio surveys are ideal for selecting orientation-independent
samples of extragalactic sources because the sample members are selected by
virtue of their isotropic steep-spectrum extended emission. We use the new 7C
Redshift Survey along with the brighter 3CRR and 6C samples to investigate the
fraction of objects with observed broad emission lines - the `quasar fraction'
- as a function of redshift and of radio and narrow emission line luminosity.
We find that the quasar fraction is more strongly dependent upon luminosity
(both narrow line and radio) than it is on redshift. Above a narrow [OII]
emission line luminosity of log L_[OII] > 35 W (or radio luminosity log L_151 >
26.5 W/Hz/sr), the quasar fraction is virtually independent of redshift and
luminosity; this is consistent with a simple unified scheme with an obscuring
torus with a half-opening angle theta_trans approx 53 degrees. For objects with
less luminous narrow lines, the quasar fraction is lower. We show that this is
not due to the difficulty of detecting lower-luminosity broad emission lines in
a less luminous, but otherwise similar, quasar population. We discuss evidence
which supports at least two probable physical causes for the drop in quasar
fraction at low luminosity: (i) a gradual decrease in theta_trans and/or a
gradual increase in the fraction of lightly-reddened (0 < A(V) < 5)
lines-of-sight with decreasing quasar luminosity; and (ii) the emergence of a
distinct second population of low luminosity radio sources which, like M87,
lack a well-fed quasar nucleus and may well lack a thick obscuring torus.

</DOC>
<DOC>
<DOCNO> 80814 </DOCNO>
Simulation of SU(2) Dynamical Fermion at Finite Chemical Potential and


  SU(2) lattice gauge theory with dynamical fermion at non-zero chemical
potential and at finite temperature is studied. We focus on the influence of
chemical potential for quark condensate and mass of pseudoscalar meson at
finite temperature.
 Hybrid Monte Carlo simulations with $N_f=8$ staggered fermions are carried out
on $12 \times 12\times 24 \times 4$ lattice. At $\beta=1.1$ and
$m_{q}=$0.05,0.07,0.1, we calculate the quark condensate and masses of
pseudoscalar meson consisting of light and heavier quarks for chemical
potential $\mu=$ 0.0,0.02,0.05,0.1,0.2.

</DOC>
<DOC>
<DOCNO> 119979 </DOCNO>
New identification of the near infrared Source in the "born-again"


  The central dust knot V605 Aql (= Nova Aql 1919) in the planetary nebula
  A58 is the result of a late-helium flash. Previous near infrared (NIR)
measurements yield very bright fluxes. This exceeds model predictions, based on
other wavelengths and estimates of the visual extinction within the object, by
a factor of 100. Using NIR imaging by the DENIS instrument, we found that the
source was misidentified in previous (single channel photometer) observations.
We present the NIR flux of A58 and identify an unrelated stellar field source,
which in fact represents the NIR source attributed to A58, according to the
literature. The new identification is consistent with model predictions for the
source. An accurate astrometry for the core of A58 is also provided.

</DOC>
<DOC>
<DOCNO> 11827 </DOCNO>
Monte Carlo Simulation of Long Chain Polymer Melts: Crossover from Rouse


  We present data of Monte Carlo simulations for monodisperse linear polymer
chains in dense melts with degrees of polymerization between N=16 and N=512.
The aim of this study is to investigate the crossover from Rouse-like dynamics
for short chains to reptation-like dynamics for long chains. To address this
problem we calculate a variety of different quantities: standard mean-square
displacements of inner monomers and of the chain's center of mass, the recently
proposed cubic invariant, persistence of bond-vector orientation with time, and
the auto-correlation functions of the bond vector, the end-to-end vector and
the Rouse modes. This analysis reveals that the crossover from non- to
entangled dynamics is very protracted. Only the largest chain length N=512,
which is about 13 times larger than the entanglement length, shows evidence for
reptation.

</DOC>
<DOC>
<DOCNO> 174445 </DOCNO>
Cross Sections for the Electron Activation of Gamma-Ray Fluorescence


  We report cross sections for the direct excitation of gamma-ray transitions
up to 200 keV by the transient electromagnetic fields of electrons from a beam,
for incident kinetic energies of 500 keV and 5 MeV. The cross sections for the
electron activation of gamma-ray fluorescence are of the order of 300 nanobarns
for an electron incident kinetic energy of 500 keV, and are of the order of 10
microbarns for an electron incident kinetic energy of 5 MeV. The electron
excitation of nuclear transitions may lead to the development of pulsed sources
of gamma radiation of narrowly defined energy.

</DOC>
<DOC>
<DOCNO> 116489 </DOCNO>
Dicluster Stopping in a Degenerate Electron Gas


  In this paper we report on our theoretical studies of various aspects of the
correlated stopping power of two point-like ions (a dicluster) moving in close
but variable vicinity of each other in some metallic target materials the
latter being modelled by a degenerate electron gas with appropriate densities.
Within the linear response theory we have made a comprehensive investigation of
correlated stopping power, vicinage function and related quantities for a
diproton cluster in two metallic targets, aluminum and copper, and present
detailed and comparative results for three approximations to the electron gas
dielectric function, namely the plasmon-pole approximation without and with
dispersion as well as with the random phase approximation. The results are also
compared, wherever applicable, with those for an individual projectile.

</DOC>
<DOC>
<DOCNO> 10700 </DOCNO>
Nonlinear $\sigma$ model for disordered superconductors


  We suggest a novel nonlinear $\sigma$-model for the description of disordered
superconductors. The main distinction from existing models lies in the fact
that the saddle point equation is solved non-perturbatively in the
superconducting pairing field. It allows one to use the model both in the
vicinity of the metal-superconductor transition and well below its critical
temperature with full account for the self-consistency conditions. We show that
the model reproduces a set of known results in different limiting cases, and
apply it for a self-consistent description of the proximity effect at the
superconductor-metal interface.

</DOC>
<DOC>
<DOCNO> 68662 </DOCNO>
A Model of Quark and Lepton Masses I: The Neutrino Sector


  If neutrinos have masses, why are they so tiny? Are these masses of the Dirac
type or of the Majorana type? We are already familiar with the mechanism of how
to obtain a tiny Majorana neutrino mass by the famous see-saw mechanism. The
question is: Can one build a model in which a tiny Dirac neutrino mass arises
in a more or less "natural" way? What would be the phenomenological
consequences of such a scenario, other than just merely reproducing the
neutrino mass patterns for the oscillation data? In this article, a systematic
and detailed analysis of a model is presented, with, as key components, the
introduction of a family symmetry as well as a new SU(2) symmetry for the
right-handed neutrinos. In particular, in addition to the calculations of light
neutrino Dirac masses, interesting phenomenological implications of the model
will be presented.

</DOC>
<DOC>
<DOCNO> 120459 </DOCNO>
Direct Simulation of Dense Stellar Systems with GRAPE-6


  In this paper we describe the current status of the GRAPE-6 project to
develop a special-purpose computer with a peak speed exceeding 100 Tflops for
the simulation of astrophysical N-body problems. One of the main targets of the
GRAPE-6 project is the simulation of dense stellar systems. In this paper,
therefore, we overview the basic algorithms we use for the simulation of dense
stellar systems and their characteristics. We then describe how we designed
GRAPE hardwares to meet the requirements of these algorithms. GRAPE-6 will be
completed by the year 2001. As an example of what science can be done on
GRAPE-6, we describe our work on the galactic center with massive black holes
performed on GRAPE-4, the predecessor of GRAPE-6.

</DOC>
<DOC>
<DOCNO> 70605 </DOCNO>
Damping of very soft moving quarks in high-temperature QCD


  We determine the analytic expression of the damping rates for very soft
moving quarks in an expansion to second order in powers of their momentum in
the context of QCD at high temperature. The calculation is performed using the
hard-thermal-loop-summed perturbation scheme. We describe the range of validity
of the expansion and make a comparison with other calculations, particularly
those using a magnetic mass as a shield from infrared sensitivity. We discuss
the possible occurrence of infrared divergences in our results and argue that
they are due to magnetic sensitivity.

</DOC>
<DOC>
<DOCNO> 151495 </DOCNO>
Interacting branes, dual branes, and dyonic branes: a unifying


  This paper presents a general covariant lagrangian framework for the dynamics
of a system of closed n-branes and dual (D-n-4)-branes in D dimensions,
interacting with a dynamical (n+1)-form gauge potential. The framework proves
sufficiently general to include also a coupling of the branes to (the bosonic
sector of) a dynamical supergravity theory. We provide a manifestly
Lorentz-invariant and S-duality symmetric Lagrangian, involving the (n+1)-form
gauge potential and its dual (D-n-3)-form gauge potential in a symmetric way.
The corresponding action depends on generalized Dirac-strings. The requirement
of string-independence of the action leads to Dirac-Schwinger quantization
conditions for the charges of branes and dual branes, but produces also
additional constraints on the possible interactions. It turns out that a system
of interacting dyonic branes admits two quantum mechanically inequivalent
formulations, involving inequivalent quantization conditions. Asymmetric
formulations involving only a single vector potential are also given. For the
special cases of dyonic branes in even dimensions known results are easily
recovered. As a relevant application of the method we write an effective action
which implements the inflow anomaly cancellation mechanism for interacting
heterotic strings and five-branes in D=10. A consistent realization of this
mechanism requires, in fact, dynamical p-form potentials and a systematic
introduction of Dirac-strings.

</DOC>
<DOC>
<DOCNO> 10182 </DOCNO>
Many-Electron Trial Wave Functions for Inhomogeneous Solids


  Quantum Monte Carlo simulations of interacting electrons in solids often use
Slater-Jastrow trial wave functions with Jastrow factors containing one- and
two-body terms. In uniform systems the long-range behavior of the two-body term
may be deduced from the random-phase approximation (RPA) of Bohm and Pines.
Here we generalize the RPA to nonuniform systems. This gives the long-range
behavior of the inhomogeneous two-body correlation term and provides an
accurate analytic expression for the one-body term. It also explains why
Slater-Jastrow trial wave functions incorporating determinants of Hartree-Fock
or density-functional orbitals are close to optimal even in the presence of an
RPA Jastrow factor. After adjusting the inhomogeneous RPA Jastrow factor to
incorporate the known short-range behavior, we test it using variational Monte
Carlo calculations. We find that the most important aspect of the two-body term
is the short-range behavior due to electron-electron scattering, although the
long-range behavior described by the RPA should become more important at high
densities.

</DOC>
<DOC>
<DOCNO> 101632 </DOCNO>
Moduli spaces of stable sheaves on abelian surfaces


  In this paper, we consider moduli spaces of stable sheaves on abelian
surfaces. Our main assumption is the primitivity of the associated Mukai
vector. We construct many isomorphisms of muduli spaces induced by
Fourier-Mukai functor. As an application, we show that deformation type of
these spaces are determined by their dimension. We next show that the fiber of
the albanese map is irreducible symplectic manifolds In particular, we describe
the period by using Mukai lattice.
  We also discuss deformation type of moduli spaces of stable sheaves on K3
surfaces.

</DOC>
<DOC>
<DOCNO> 12483 </DOCNO>
Glass transition in the quenched and annealed version of the frustrated


  In this paper we study the 3d frustrated lattice gas model in the annealed
version, where the disorder is allowed to evolve in time with a suitable
kinetic constraint. Although the model does not exhibit any thermodynamic
transition it shows a diverging peak at some characteristic time in the
dynamical non-linear susceptibility, similar to the results on the p-spin model
in mean field and Lennard-Jones mixture recently found by Franz et al.
[cond-mat/9905433]. Comparing these results to those obtained in the model with
quenched interactions, we conclude that the critical behavior of the dynamical
susceptibility is reminiscent of the thermodynamic transition present in the
quenched model, and signaled by the divergence of the static non-linear
susceptibility, suggesting therefore a similar mechanism also in supercooled
glass-forming liquids.

</DOC>
<DOC>
<DOCNO> 85008 </DOCNO>
Wave Propagation in Nontrivial Backgrounds


  It is well known that waves propagating in a nontrivial medium develop
``tails''. However, the exact form of the late-time tail has so far been
determined only for a narrow class of models. We present a systematic analysis
of the tail phenomenon for waves propagating under the influence of a {\it
general} scattering potential $V(x)$. It is shown that, generically, the
late-time tail is determined by spatial {\it derivatives} of the potential. The
central role played by derivatives of the scattering potential appears not to
be widely recognized. The analytical results are confirmed by numerical
calculations.

</DOC>
<DOC>
<DOCNO> 152355 </DOCNO>
The one-loop effective action of noncommutative {\cal N}=4 super


  We study the gauge transformation of the recently computed one-loop
four-point function of {\cal N}=4 supersymmetric Yang-Mills theory with gauge
group U(N). The contributions from nonplanar diagrams are not gauge invariant.
We compute their gauge variation and show that it is cancelled by the variation
from corresponding terms of the one-loop five-point function. This mechanism is
general: it insures the gauge invariance of the noncommutative one-loop
effective action.

</DOC>
<DOC>
<DOCNO> 150560 </DOCNO>
Multi-Instantons, Supersymmetry and Topological Field Theories


  In this letter we argue that instanton-dominated Green's functions in N=2
Super Yang-Mills theories can be equivalently computed either using the
so-called constrained instanton method or making reference to the topological
twisted version of the theory. Defining an appropriate BRST operator (as a
supersymmetry plus a gauge variation), we also show that the expansion
coefficients of the Seiberg-Witten effective action for the low-energy degrees
of freedom can be written as integrals of total derivatives over the moduli
space of self-dual gauge connections.

</DOC>
<DOC>
<DOCNO> 11732 </DOCNO>
Boundary Effects on Dynamic Behavior of Josephson-Junction Arrays


  The boundary effects on the current-voltage characteristics in
two-dimensional arrays of resistively shunted Josephson junctions are examined.
In particular, we consider both the conventional boundary conditions (CBC) and
the fluctuating twist boundary conditions (FTBC), and make comparison of the
obtained results. It is observed that the CBC, which have been widely adopted
in existing simulations, may give a problem in scaling, arising from rather
large boundary effects; the FTBC in general turn out to be effective in
reducing the finite-size effects, yielding results with good scaling behavior.
To resolve the discrepancy between the two boundary conditions, we propose that
the proper scaling in the CBC should be performed with the boundary data
discarded: This is shown to give results which indeed scale well and are the
same as those from the FTBC.

</DOC>
<DOC>
<DOCNO> 100902 </DOCNO>
On spaces in countable web


  We show that a Tychonoff discretely star-Lindelof space can have arbitrarily
big extent and note that there are consistent examples of normal discretely
star-Lindelof spaces with uncountable extent.

</DOC>
<DOC>
<DOCNO> 85327 </DOCNO>
Canonical and quantum FRW cosmological solutions in M-theory


  We present the canonical and quantum cosmological investigation of a
spatially flat, four-dimensional Friedmann-Robertson-Walker (FRW) model that is
derived from the M-theory effective action obtained originally by Billyard,
Coley, Lidsey and Nilsson (BCLN). The analysis makes use of two sets of
canonical variables, the Shanmugadhasan gauge invariant canonical variables and
the ``hybrid'' variables which diagonalise the Hamiltonian. We find the
observables and discuss in detail the phase space of the classical theory. In
particular, a region of the phase space exists that describes a
four-dimensional FRW spacetime first contracting from a strong coupling regime
and then expanding to a weak coupling regime, while the internal space ever
contracts. We find the quantum solutions of the model and obtain the positive
norm Hilbert space of states. Finally, the correspondence between wave
functions and classical solutions is outlined.

</DOC>
<DOC>
<DOCNO> 10189 </DOCNO>
The influence of chiral surface states on the London penetration depth


  The London penetration depth for the unconventional superconductor
Sr$_2$RuO$_4$ is analyzed assuming an order parameter which breaks time
reversal symmetry and parity simultaneously. Such a superconducting state
possesses chiral quasiparticle states with subgap energies at the surface. We
show that these subgap states can give a significant contribution to the
low-temperature behavior of the London penetration depth yielding a $ T^2 $
power-law even though bulk quasiparticle spectrum is gapped. The presence of
several electron bands gives rise to interband transition among the subgap
surface states and influences the properties of the surface impedance.
Furthermore, the surface states lead also to a non-linear Meissner effect.

</DOC>
<DOC>
<DOCNO> 119168 </DOCNO>
Cool Companions to Hot White Dwarfs


  We describe a near-IR photometric search for cool red dwarf companions to hot
EUV-detected white dwarfs (WDs). While some composite systems have been found
optically among WDs detected in recent EUV All-Sky Surveys, we develop an IR
technique that probes farther down the main sequence, detecting yet more
companions. We use detailed DA model atmosphere fits to optical spectra to
predict K magnitudes and distances, against which we contrast our near-IR
observations. Our photometric survey reveals 10 DAs with a significant excess
in both J and K. Half are newly discovered, and are most likely previously
unrecognized binary systems. Neither the frequency of infrared excess nor the
mass estimate of the red dwarf companion correlate with white dwarf mass, as
might be expected if either the EUV detectability or mass of the white dwarfs
were significantly affected by a companion. Infrared spectra of these systems
should help to determine the mass and spectral type of the cool companions
presumably causing the IR excess, leading to better estimates of the mass ratio
distribution in binaries.
   Counting previously known binaries, and resolved pairs, we find the total
binary fraction of the sample is at least a third. Since most WD progenitors
had initial masses larger than about 2 solar masses, we thus provide a
photometric measure of the binary fraction of high mass stars that would be
difficult to perform in high mass main sequence stars. We estimate that 90% of
the companions are of type K or later.

</DOC>
<DOC>
<DOCNO> 11660 </DOCNO>
A polarized neutron-scattering study of the Cooper-pair moment in


  We report a study of the magnetization density in the mixed state of the
unconventional superconductor S2RuO4. On entering the superconducting state we
find no change in the magnitude or distribution of the induced moment for a
magnetic field of 1 Tesla applied within the RuO2 planes. Our results are
consistent with a spin-triplet Cooper pairing with spins lying in the basal
plane. This is in contrast with similar experiments performed on conventional
and high-Tc superconductors.

</DOC>
<DOC>
<DOCNO> 69442 </DOCNO>
Limits on isocurvature fluctuations from Boomerang and MAXIMA


  We present the constraints on isocurvature fluctuations for a flat universe
implied by the Boomerang and Maxima-1 data on the anisotropy of the cosmic
microwave background. Because the new data defines the shape of the angular
power spectrum in the region of the first acoustic peaks much more clearly than
earlier data, even a tilted pure isocurvature model is now ruled out. However,
a mixed model with a sizable isocurvature contribution remains allowed. We
consider primordial fluctuations with different spectral indices for the
adiabatic and isocurvature perturbations, and find that the 95% C.L. upper
limit to the isocurvature contribution to the low multipoles is $\alpha \leq
0.63$. The upper limit to the contribution in the ${\l}\sim 200$ region is
$\alpha_{200} \leq 0.13$.

</DOC>
<DOC>
<DOCNO> 68383 </DOCNO>
Timelike and spacelike QCD characteristics of the $e^+e^-$ annihilation


  We consider the Adler $D$-function, which is defined in the spacelike region,
and the $e^+e^-$ annihilation ratio smeared, according to the Poggio, Quinn,
and Weinberg method, which is determined for timelike argument. We show that
the method of the nonperturbative $a$-expansion allows one to describe these
Euclidean and Minkowskian characteristics of the process of $e^+e^-$
annihilation down to the lowest energy scales.

</DOC>
<DOC>
<DOCNO> 169846 </DOCNO>
L'ordinateur quantique


  Project of an undergraduate student in physics (4th year) about the concept
of quantum computers (QC) and its social impact. After a thourough theoretical
introduction (chap. 2), the recent debate about NMR-based QC is dealt with in
detail (chap. 3). Chapter 4 comments on the figure of the number of articles
published on the subject, showing the dramatic growth after the publication of
Shor's algorithm.

</DOC>
<DOC>
<DOCNO> 102026 </DOCNO>
Higher-dimensional BF theories in the Batalin-Vilkovisky formalism: The


  This paper analyzes in details the Batalin-Vilkovisky quantization procedure
for BF theories on n-dimensional manifolds and describes a suitable
superformalism to deal with the master equation and the search of observables.
In particular, generalized Wilson loops for BF theories with additional
polynomial B-interactions are discussed in any dimensions. The paper also
contains the explicit proofs to the Theorems stated in math.QA/0003073.

</DOC>
<DOC>
<DOCNO> 118786 </DOCNO>
The black hole in IC 1459 from HST observations of the ionized gas disk


  The peculiar elliptical galaxy IC 1459 (M_V = -21.19, D = 16.5 Mpc) has a
fast counterrotating stellar core, stellar shells and ripples, a blue nuclear
point source and strong radio core emission. We present results of a detailed
HST study of IC 1459, and in particular its central gas disk, aimed a
constraining the central mass distribution. We obtained WFPC2 narrow-band
imaging centered on the Halpha+[NII] emission lines to determine the flux
distribution of the gas emission at small radii, and we obtained FOS spectra at
six aperture positions along the major axis to sample the gas kinematics. We
construct different dynamical models for the Halpha+[NII] and Hbeta kinematics
that include a supermassive black hole, and in which the stellar mass
distribution is constrained by the observed surface brightness distribution and
ground-based stellar kinematics. All models are consistent with a black hole
mass in the range Mbh=1-4 x 10^8 Msun, and models without a black hole are
always ruled out at high confidence.

</DOC>
<DOC>
<DOCNO> 120331 </DOCNO>
Scintillation-Induced Circular Polarization in Pulsars and Quasars


  We present a physical interpretation for the generation of circular
polarization resulting from the propagation of radiation through a magnetized
plasma in terms of a rotation measure gradient, or `Faraday wedges'. Criteria
for the observability of scintillation-induced circular polarization are
identified. Application of the theory to the circular polarization in pulsars
and compact extragalactic sources is discussed.

</DOC>
<DOC>
<DOCNO> 99894 </DOCNO>
Renormalization of the Regularized Relativistic Electron-Positron Field


  We consider the relativistic electron-positron field interacting with itself
via the Coulomb potential defined with the physically motivated, positive,
density-density quartic interaction. The more usual normal-ordered Hamiltonian
differs from the bare Hamiltonian by a quadratic term and, by choosing the
normal ordering in a suitable, self-consistent manner, the quadratic term can
be seen to be equivalent to a renormalization of the Dirac operator. Formally,
this amounts to a Bogolubov-Valatin transformation, but in reality it is
non-perturbative, for it leads to an inequivalent, fine-structure dependent
representation of the canonical anticommutation relations. This
non-perturbative redefinition of the electron/positron states can be
interpreted as a mass, wave-function and charge renormalization, among other
possibilities, but the main point is that a non-perturbative definition of
normal ordering might be a useful starting point for developing a consistent
quantum electrodynamics.

</DOC>
<DOC>
<DOCNO> 70142 </DOCNO>
On Sub-Millimeter Forces From Extra Dimensions


  We show that in theories with large extra dimensions forces mediated by a
bulk dilaton and bulk gauge fields may be parametrically (exponentially) weaker
than gravity due to the suppression of their wave-functions on a brane. This is
the case when dilaton gets stabilized by certain strongly coupled dynamics on
the brane, or the bulk gauge symmetries are spontaneously broken by the Higgs
mechanism on the worldvolume. At distances smaller than the size of a largest
extra dimension these particles produce the force-law which decreases with
distance faster than high-dimensional gravity. For a millimeter size extra
dimensions predicted deviations are in the range which may be detected in
sub-millimeter gravity measurements.

</DOC>
<DOC>
<DOCNO> 151718 </DOCNO>
Understanding Skyrmions using Rational Maps


  We discuss an ansatz for Skyrme fields in three dimensions which uses
rational maps between Riemann spheres, and produces shell-like structures of
polyhedral form. Houghton, Manton and Sutcliffe showed that a single rational
map gives good approximations to the minimal energy Skyrmions up to baryon
number of order ten. We show how the method can be generalised by using two or
more rational maps to give a double-shell or multi-shell structure.
Particularly interesting examples occur at baryon numbers twelve and fourteen.

</DOC>
<DOC>
<DOCNO> 150725 </DOCNO>
The condition 0 < Z < 1 and an intrinsic mass scale in Quantum Field


  In this work, we suggest a view-point that leads to an intrinsic mass scale
in Quantum Field Theories. This view-point is fairly independent of dynamical
details of a QFT and does not rely on any particular framework to go beyond the
standard Model. We use the setting of the nonlocal quantum field theories NLQFT
with a finite scale parameter Lambda, which are unitary for finite Lambda. We
propose that the condition 0 < Z < 1 [wherever proven] can be rigorously
implemented/imposed in such theories and that it implies the existence of a
mass scale Lambda that can be determined from this condition. We derive the
nonlocal analogue of the above relation [which is a finite relation in NLQFT]
and demonstrate that it can be arrived at only from general principles. We
further propose that the nonlocal formulation should be looked as an effective
field theory that incorporates the effect of dynamics beyond an energy scale
and which breaks at the intrinsic scale Lambda so obtained. Beyond this scale
it should be replaced by another [perhaps, a more fundamental] theory. We
provide a heuristic justification for this view-point.

</DOC>
<DOC>
<DOCNO> 121117 </DOCNO>
ASTRO-F - The next generation of mid-infrared surveys


  We present basic observational strategies for ASTRO-F (also known as the
Imaging Infra Red Surveyor (IRIS)) to be launched in 2004 by the Japanese
Institute of Space and Astronautical Science (ISAS). We examine 2 survey
scenarios, a deep ~1sq.deg. survey reaching sensitivities an order of magnitude
below than the deepest surveys performed by ISO in the mid-IR, and a shallow
\~18sq.deg mid-infrared (7-25um in 6 bands) covering an area greater than the
entire area covered by all ISO mid-IR surveys. Using 2 cosmological models the
number of galaxies predicted for each survey is calculated. The first model
uses an enhancement of the pure luminosity evolution model of Pearson &
Rowan-Robinson while the new models incorporate a strongly evolving ULIG
component. For the deep survey, between 20,000-30,000 galaxies should be
detected in the shortest wavebands and ~5000 in the longest (25um) band. The
shallow survey would be expected to detect of the order of 100,000 - 150,000
sources.

</DOC>
<DOC>
<DOCNO> 40303 </DOCNO>
Measurement of the Angular Distribution of Electrons from W->e nu Decays


  We present the first measurement of the electron angular distribution
parameter alpha_2 in W to e nu events produced in proton-antiproton collisions
as a function of the W boson transverse momentum. Our analysis is based on data
collected using the D0 detector during the 1994--1995 Fermilab Tevatron run. We
compare our results with next-to-leading order perturbative QCD, which predicts
an angular distribution of (1 +/- alpha_1 cos theta* + alpha_2 cos^2 theta*),
where theta* is the polar angle of the electron in the Collins-Soper frame. In
the presence of QCD corrections, the parameters alpha_1 and alpha_2 become
functions of p_T^W, the W boson transverse momentum. This measurement provides
a test of next-to-leading order QCD corrections which are a non-negligible
contribution to the W boson mass measurement.

</DOC>
<DOC>
<DOCNO> 152465 </DOCNO>
Comments on: ``Weinberg's Nonlinear Quantum Mechanics and


  Contrary to the opinion of J. Polchinski [Phys.Rev.Lett. {\bf 66}, 397-400
(1991)], the phenomenon of superluminal messages in nonlinear versions of
quantum mechanics is not a specific difficulty in a class of theories
formulated by S. Weinberg [Ann.Phys. (N.Y.), {\bf 194}, 336-386 (1989)]. It
appears in all schemes which try to enlarge the orthodox class of observables,
while conserving the traditional structure of the pure and mixed states.

</DOC>
<DOC>
<DOCNO> 101133 </DOCNO>
Elliptic Genera of Singular Varieties


  Orbifold elliptic genus and elliptic genus of singular varieties are
introduced and relation between them is studied. Elliptic genus of singular
varieties is given in terms of a resolution of singularities and extends the
elliptic genus of Calabi-Yau hypersurfaces in Fano Gorenstein toric varieties
introduced earlier. Orbifold elliptic genus is given in terms of the fixed
point sets of the action. We show that the generating function for this
orbifold elliptic genus $\sum Ell_{orb}(X^n,\Sigma_n)p^n$ for symmetric groups
$\Sigma_n$ acting on $n$-fold products coincides with the one proposed by
Dijkgraaf, Moore, Verlinde and Verlinde. Two notions of elliptic genera are
conjectured to coincide.

</DOC>
<DOC>
<DOCNO> 12098 </DOCNO>
Theory of Coherent Optical Control of Exciton Spin Dynamics in a


  We use the spin-polarized excitons in a single quantum dot to design optical
controls for basic operations in quantum computing. We examine the ultrafast
nonlinear optical processes required and use the coherent nonlinear optical
responses to deduce if such processes are physically reasonable. The importance
and construction of an entangled state of polarized exciton states in a single
quantum dot is explained. We put our proposal in perspective with respect to a
number of theoretical suggestions of utilizing the semiconductor quantum dots.

</DOC>
<DOC>
<DOCNO> 122350 </DOCNO>
Finding Signatures of the Youngest Starbursts


  Embedded massive starclusters have recently been identified in several nearby
galaxies by means of the radio-wave thermal bremsstrahlung emission from their
surrounding HII regions. Energy requirements imply that these
optically-obscured starclusters contain 500-1000 O-type stars, making them
similar to the ``super starclusters'' observed in many dwarf starbursts and
mergers. Based on their high free-free optical depth and visual extinctions of
A_V>>10 mag., these massive ``ultra-dense'' HII regions (UDHIIs) are distinct
signatures of the youngest, most compact super starclusters. UDHII regions may
represent the earliest stages of globular cluster formation. We review the
properties of presently-known UDHIIs, and we outline a pictoral evolutionary
taxonomy for massive cluster formation which is analogous to the more familiar
evolutionary sequence for individual stars.

</DOC>
<DOC>
<DOCNO> 178887 </DOCNO>
Chaos and isospin symmetry breaking in rotational nuclei


  For nuclei with N = Z, the isospin degree of freedom is important and, for
deformed systems, rotational bands of different isospin may be expected at low
excitation energies. We have investigated, in a simple model space, the
influence of the isospin-breaking Coulomb interaction on the degree of
chaoticity of these rotational bands. The statistical measures used rely on an
analysis of level-spacing distributions, which are extremely difficult to
measure experimentally. We show, however, that the overlap intergrals between
states of similar frequency reflect well the degree of chaoticity. This
quantity is closely related to the experimentally more accessible gamma-decay
``spreading width''.

</DOC>
<DOC>
<DOCNO> 8653 </DOCNO>
Mean parameter model for the Pekar-Fr\"{o}hlich polaron in a


  The polaron energy and the effective mass are calculated for an electron
confined in a finite quantum well constructed of $GaAs/Al_x Ga_{1-x} As$
layers. To simplify the study we suggest a model in which parameters of a
medium are averaged over the ground-state wave function. The rectangular and
the Rosen-Morse potential are used as examples.
  To describe the confined electron properties explicitly to the second order
of perturbations in powers of the electron-phonon coupling constant we use the
exact energy-dependent Green function for the Rosen-Morse confining potential.
In the case of the rectangular potential, the sum over all intermediate virtual
states is calculated. The comparison is made with the often used leading term
approximation when only the ground-state is taken into account as a virtual
state. It is shown that the results are quite different, so the incorporation
of all virtual states and especially those of the continuous spectrum is
essential.
  Our model reproduces the correct three-dimensional asymptotics at both small
and large widths. We obtained a rather monotonous behavior of the polaron
energy as a function of the confining potential width and found a peak of the
effective mass. The comparison is made with theoretical results by other
authors. We found that our model gives practically the same (or very close)
results as the explicit calculations for potential widths $L \geq 10 \AA$.

</DOC>
<DOC>
<DOCNO> 9221 </DOCNO>
Exact Potts Model Partition Function on Strips of the Triangular Lattice


  In this paper we present exact calculations of the partition function $Z$ of
the $q$-state Potts model and its generalization to real $q$, for arbitrary
temperature on $n$-vertex strip graphs, of width $L_y=2$ and arbitrary length,
of the triangular lattice with free, cyclic, and M\"obius longitudinal boundary
conditions. These partition functions are equivalent to Tutte/Whitney
polynomials for these graphs. The free energy is calculated exactly for the
infinite-length limit of the graphs, and the thermodynamics is discussed.
Considering the full generalization to arbitrary complex $q$ and temperature,
we determine the singular locus ${\cal B}$ in the corresponding ${\mathbb C}^2$
space, arising as the accumulation set of partition function zeros as $n \to
\infty$. In particular, we study the connection with the T=0 limit of the Potts
antiferromagnet where ${\cal B}$ reduces to the accumulation set of chromatic
zeros. Comparisons are made with our previous exact calculation of Potts model
partition functions for the corresponding strips of the square lattice. Our
present calculations yield, as special cases, several quantities of
graph-theoretic interest.

</DOC>
<DOC>
<DOCNO> 121695 </DOCNO>
What Makes the Sun Tick? - The Origin of the Solar Cycle


  In contrast to the situation with the geodynamo, no breakthrough has been
made in the solar dynamo problem for decades. Since the appearance of
mean-field electrodynamics in the 1960's, the only really significant advance
was in the field of flux tube theory and flux emergence calculations. These new
results, together with helioseismic evidence, have led to the realization that
the toroidal magnetic flux giving rise to activity phenomena must be stored and
presumably generated below the convection zone proper, in what I will call the
DOT (Dynamo-Overshoot-Tachoclyne) layer. The only segment of the problem we can
claim to basically understand is the transport of flux from this layer to the
surface. On the other hand, as reliable models for the DOT layer do not exist
we are clueless concerning the precise mechanisms responsible for
toroidal/poloidal flux conversion and for characteristic migration patterns
(extended butterfly diagram) and periodicities. Even the most basic result of
mean-field theory, the interpretation of the butterfly diagram as an
alpha-omega dynamo wave, has been questioned. This review therefore will
necessarily ask more questions than give answers. Some of these key questions
are
 - Structure of the DOT layer
 - alpha-quenching and distributed dynamo
 - High-latitude migration patterns and their interpretation
 - The ultimate fate of emerged flux

</DOC>
<DOC>
<DOCNO> 8891 </DOCNO>
Study of pseudogap in underdoped cuprate


  A mean field SDW analysis of pseudogap in the underdoped cuprates is proposed
on the basis of the $t-t^{\prime}-U$ Hubbard model. The prediction of our
theory is consistent with the experiment quite well within the uncertainty of
the present experimental measurement. Therefore we argue that the pseudogap
phenomenon in the underdoped cuprates can be well explained within the mean
field approximation.

</DOC>
<DOC>
<DOCNO> 170498 </DOCNO>
Semiclassical theory of cavity-assisted atom cooling


  We present a systematic semiclassical model for the simulation of the
dynamics of a single two-level atom strongly coupled to a driven high-finesse
optical cavity. From the Fokker-Planck equation of the combined atom-field
Wigner function we derive stochastic differential equations for the atomic
motion and the cavity field. The corresponding noise sources exhibit strong
correlations between the atomic momentum fluctuations and the noise in the
phase quadrature of the cavity field. The model provides an effective tool to
investigate localisation effects as well as cooling and trapping times. In
addition, we can continuously study the transition from a few photon quantum
field to the classical limit of a large coherent field amplitude.

</DOC>
<DOC>
<DOCNO> 13040 </DOCNO>
Comment on "Nature of the Spin Glass State"


  We show that the interface excitations of Palassini-Young and Krzakala-Martin
cannot yield new thermodynamic states.

</DOC>
<DOC>
<DOCNO> 120507 </DOCNO>
The Newton Wonder in Mechanics


  Application of Newton's ideas from "Principia" gives many new results in
mechanics. Here we explore the question ``What form of extra force will
maintain the magnitude of a vector constant of the motion while changing its
direction?''

</DOC>
<DOC>
<DOCNO> 152015 </DOCNO>
Five-Dimensional Gauged Supergravities with Universal Hypermultiplet and


  We present five dimensional gauged supergravity with universal hypermultiplet
on M_4 \times S^1 / Z_2 coupled supersymmetrically to three-branes located at
the fixed points. The construction is extended to the smooth picture with
auxiliary singlet and four-form fields. The model admits the Randall-Sundrum
solution as a BPS vacuum with vanishing energy. We give the form of all
KK-tower modes for fields present in the model.

</DOC>
<DOC>
<DOCNO> 10673 </DOCNO>
Phase Transition and Acoustic Localization in Arrays of Air-Bubbles in


  Wave localization is a ubiquitous phenomenon. It refers to situations that
transmitted waves in scattering media are trapped in space and remain confined
in the vicinity of the initial site until dissipated. Here we report a phase
transition from acoustically extended to localized states in arrays of
identical air-filled bubbles in water. It is shown that the acoustic
localization in such media is coincident with the complete band gap of a
lattice arrangement of the air-bubbles. When the localization or the band gap
occurs, a peculiar collective behavior of the bubbles appears.

</DOC>
<DOC>
<DOCNO> 40218 </DOCNO>
The Ratio of Jet Cross Sections at s**(1/2)=630 GeV and 1800 GeV


  The DO Collaboration has measured the inclusive jet cross section in
proton-antiproton collisions at s**2 = 630 GeV. The results for
pseudorapidities -0.5 to 0.5 are combined with our previous results at s**2 =
1800 GeV to form a ratio of cross sections with smaller uncertainties than
either individual measurement. Next-to-leading-order QCD predictions show
excellent agreement with the measurement at 630 GeV; agreement is also
satisfactory for the ratio. Specifically, despite a 10% to 15% difference in
the absolute normalization, the dependence of the ratio on jet transverse
momentum is very similar for data and theory.

</DOC>
<DOC>
<DOCNO> 83158 </DOCNO>
A network file system over HTTP: remote access and modification of files


  The goal of the present HTTPFS project is to enable access to remote files,
directories, and other containers through an HTTP pipe. HTTPFS system permits
retrieval, creation and modification of these resources as if they were regular
files and directories on a local filesystem. The remote host can be any UNIX or
Win9x/WinNT box that is capable of running a Perl CGI script and accessible
either directly or via a web proxy or a gateway. HTTPFS runs entirely in user
space.
    The current implementation fully supports reading as well as creating,
writing, appending, and truncating of files on a remote HTTP host. HTTPFS
provides an isolation level for concurrent file access stronger than the one
mandated by POSIX file system semantics, closer to that of AFS. Both an API
with familiar open(), read(), write(), close(), etc. calls, and an interactive
interface, via the popular Midnight Commander file browser, are provided.

</DOC>
<DOC>
<DOCNO> 13258 </DOCNO>
Dilation-induced phases of gases absorbed within a bundle of carbon


  A study is presented of the effects of gas (especially H2) absorption within
the interstitial channels of a bundle of carbon nanotubes. The ground state of
the system is determined by minimizing the total energy, which includes the
molecules' interaction with the tubes, the inter-tube interaction, and the
molecules' mutual interaction (which is screened by the tubes). The
consequences of swelling include a significant increase in the gas uptake and a
3 per cent increase in the tubes' breathing mode frecuency.

</DOC>
<DOC>
<DOCNO> 70389 </DOCNO>
Chiral Dynamics


  The effective field theory relevant for the analysis of QCD at low energies
is reviewed. The foundations of the method are discussed in some detail and a
few illustrative examples are described.

</DOC>
<DOC>
<DOCNO> 70263 </DOCNO>
Day-night asymmetry of high and low energy solar neutrino events in


  In the context of solar neutrino oscillations among active states, we briefly
discuss the current likelihood of Mikheyev-Smirnov-Wolfenstein (MSW) solutions
to the solar neutrino problem, which appear to be currently favored at large
mixing, where small Earth regeneration effects might still be observable in
Super-Kamiokande (SK) and in the Sudbury Neutrino Observatory (SNO). We point
out that, since such effects are larger at high (low) solar neutrino energies
for high (low) values of the mass square difference \delta m^2, it may be
useful to split the night-day rate asymmetry in two separate energy ranges. We
show that the difference \Delta of the night-day asymmetry at high and low
energy may help to discriminate the two large-mixing solutions at low and high
\delta m^2 through a sign test, both in SK and in SNO, provided that the
sensitivity to \Delta can reach the (sub)percent level.

</DOC>
<DOC>
<DOCNO> 68062 </DOCNO>
Active-sterile neutrino oscillations in the early Universe and the


  Cosmology cannot rule out the solution nu_mu <-> nu_s to the atmospheric
neutrino data and thus only Earth experiments will be able to give a definitive
answer. This conclusion holds when a generation of lepton number is taken into
account and one assumes that the sterile neutrino is also slightly mixed with
an eV-tau neutrino. This result cannot be spoiled by a chaotic generation of
lepton domains.

</DOC>
<DOC>
<DOCNO> 122132 </DOCNO>
On the Astrometric Behavior of Binary Microlensing Events


  Despite the suspected binarity for a significant fraction of Galactic lenses,
the current photometric surveys detected binary microlensing events only for a
small fraction of the total events. The detection efficiency is especially low
for non-caustic crossing events, which comprise majority of the binary lensing
events, due to the absence of distinctive features in their light curves
combined with small deviations from the standard light curve of a single
point-mass event. In addition, even they are detected, it will be difficult to
determine the solution of the binary lens parameters due to the severe
degeneracy problem. In this paper, we investigate the properties of binary
lensing events expected when they are astrometrically observed by using high
precision interferometers. For this, we construct vector field maps of excess
centroid shifts, which represent the deviations of the binary lensing centroid
shifts from those of a single lensing events as a function of source position.
  From the analysis of the maps, we find that the excess centroid shifts are
substantial in a considerably large area around caustics. In addition, they
have characteristic sizes and directions depending strongly on the source
positions with respect to the caustics and the resulting trajectories of the
light centroid (astrometric trajectories) have distinctive features, which can
be distinguished from the deviations caused by other reasons. We classify the
types of the deviations and investigate where they occur. Due to the strong
dependency of the centroid shifts on the lens system geometry combined with the
distinctive features in the observed astrometric trajectories, astrometric
binary lensing observations will provide an important tool that can probe the
properties of Galactic binary lens population.

</DOC>
<DOC>
<DOCNO> 118447 </DOCNO>
Simulation of primordial object formation


  We have included the chemical rate network responsible for the formation of
molecular Hydrogen in the N-body hydrodynamic code, Hydra, in order to study
the formation of the first cosmological at redshifts between 10 and 50. We have
tested our implementation of the chemical and cooling processes by comparing
N-body top hat simulations with theoretical predictions from a semi-analytic
model and found them to be in good agreement. We find that post-virialization
properties are insensitive to the initial abundance of molecular hydrogen. Our
main objective was to determine the minimum mass ($M_{SG}(z)$) of perturbations
that could become self gravitating (a prerequisite for star formation), and the
redshift at which this occurred. We have developed a robust indicator for
detecting the presence of a self-gravitating cloud in our simulations and find
that we can do so with a baryonic particle mass-resolution of 40 solar masses.
We have performed cosmological simulations of primordial objects and find that
the object's mass and redshift at which they become self gravitating agree well
with the $M_{SG}(z)$ results from the top hat simulations. Once a critical
molecular hydrogen fractional abundance of about 0.0005 has formed in an
object, the cooling time drops below the dynamical time at the centre of the
cloud and the gas free falls in the dark matter potential wells, becoming self
gravitating a dynamical time later.

</DOC>
<DOC>
<DOCNO> 85340 </DOCNO>
Space-time as multidimensional elastic plate


  It is suggested, that a curved 4-dimensional space-time manifold is a
strained elastic plate in multidimensional embedding space-time. Its
thicknesses along extradimensions are much less than 4-dimensional sizes.
Reduced 4-dimensional free energy density of the strained plate in a weak
strain case is similar to GR Lagrangian density of a gravitational field for
the particular value of the Poisson coefficient of the plate. Dynamical
equations of the theory are obtained by variation of the multidimensional free
energy over displacement vector components. In general case they are
inhomogeneous bewave equations.

</DOC>
<DOC>
<DOCNO> 71752 </DOCNO>
Light Hadron Spectroscopy at BEPC


  The $J/\Psi$ and $\Psi'$ experiments at the Beijing Electron Positron
Collider (BEPC) play a unique role in many aspects of light hadron
spectroscopy, such as hunting for glueballs and hybrids, extracting $u\bar
u+d\bar d$ and $s\bar s$ components of mesons, and studying excited nucleons
and hyperons, i.e., $N^*$, $\Lambda^*$, $\Sigma^*$ and $\Xi^*$ resonances.
Physics objectives, recent results and future prospects of light hadron
spectroscopy at BEPC are presented.

</DOC>
<DOC>
<DOCNO> 80780 </DOCNO>
Lattice Evidence for Gauge Field Localization on a Brane


  We examine the problem of gauge-field localization in higher-dimensional
gauge theories. In particular, we study a five-dimensional U(1) by lattice
techniques and we find that gauge fields can indeed be localized. Two models
are considered. The first one has anisotropic couplings independent of each
other and of the coordinates. It can be realized on a homogeneous but
anisotropic flat Euclidean space. The second model has couplings depending on
the extra transverse fifth direction. This model can be realized by a U(1)
gauge theory on the Randall-Sundrum background. We find that in both models a
new phase exists, the layer phase, in which a massless photon is localized on
the four-dimensional layers. We find that this phase is separated from the
strong coupling phase by a second order phase transition.

</DOC>
<DOC>
<DOCNO> 9223 </DOCNO>
Morphology transitions in three-dimensional domain growth with Gaussian


  We study the morphology of magnetic domain growth in disordered three
dimensional magnets. The disordered magnetic material is described within the
random-field Ising model with a Gaussian distribution of local fields with
width $\Delta$. Growth is driven by a uniform applied magnetic field, whose
value is kept equal to the critical value $H_c(\Delta)$ for the onset of steady
motion. Two growth regimes are clearly identified. For low $\Delta$ the growing
domain is compact, with a self-affine external interface. For large $\Delta$ a
self-similar percolation-like morphology is obtained. A multi-critical point at
$(\Delta_c$, $H_c(\Delta_c))$ separates the two types of growth. We extract the
critical exponents near $\Delta_c$ using finite-size scaling of different
morphological attributes of the external domain interface. We conjecture that
the critical disorder width also corresponds to a maximum in $H_c(\Delta)$.

</DOC>
<DOC>
<DOCNO> 152438 </DOCNO>
Poisson Structure Induced Field Theories and Models of 1+1 Dimensional


  PhD thesis TU-Vienna, May 1994. Table of Contents: 1. Introduction, 2.
Poisson Structure Induced Two Dimensional Field Theories, 3. Models of Gravity
in 1+1 Dimensions

</DOC>
<DOC>
<DOCNO> 118108 </DOCNO>
Optical off-nuclear spectra of quasar hosts and radio galaxies


  We present optical (~3200A to ~9000A) off-nuclear spectra of 26 powerful
active galaxies in the redshift range 0.1 < z < 0.3, obtained with the Mayall
and William Herschel 4-meter class telescopes. The sample consists of
radio-quiet quasars, radio-loud quasars (all with -23 > M_V > -26) and radio
galaxies of Fanaroff & Riley Type II (with extended radio luminosities and
spectral indices comparable to those of the radio-loud quasars). The spectra
were all taken approximately 5 arcseconds off-nucleus, with offsets carefully
selected so as to maximise the amount of galaxy light falling into the slit,
whilst simultaneously minimising the amount of scattered nuclear light. The
majority of the resulting spectra appear to be dominated by the integrated
stellar continuum of the underlying galaxies rather than by light from the
non-stellar processes occurring in the active nuclei, and in many cases a 4000A
break feature can be identified. The individual spectra are described in
detail, and the importance of the various spectral components is discussed.
Stellar population synthesis modelling of the spectra will follow in a
subsequent paper (Nolan et al. 2000).

</DOC>
<DOC>
<DOCNO> 71877 </DOCNO>
Nuclear structure functions and off-shell corrections


  The $n$-th moments of the nuclear structure function $F_2^A(x,Q^2)$ are
analyzed using the off-shell kinematics appropriate to describe deep inelastic
electron-nucleus scattering within the impulse approximation. It is shown that
off-shell effects are sensitive to the form of both the nuclear spectral
function and the nucleon structure function $F_2^N(x,Q^2)$, and can be as large
as $\sim 10%$ at Q$^2~\sim~2$~(GeV/c)$^2$.

</DOC>
<DOC>
<DOCNO> 150376 </DOCNO>
On consistency of the closed bosonic string with different left-right


  Closed bosonic string with different normal ordering constants $a \ne \bar a$
for the right and the left moving sectors is considered. One immediate
consequence of this choice is absence of tachyon in the physical state
spectrum. Selfconsistency of the resulting model in the "old covariant
quantization" (OCQ) framework is studyed. The model is manifestly Poincare
invariant, it has non trivial massless sector and is ghost free for $D=26, ~
a=1, ~\bar a=0$. A possibility to obtain the light-cone formulation for the
model is also discussed.

</DOC>
<DOC>
<DOCNO> 99440 </DOCNO>
Differential invariants and curved Bernstein-Gelfand-Gelfand sequences


  We give a simple construction of the Bernstein-Gelfand-Gelfand sequences of
natural differential operators on a manifold equipped with a parabolic
geometry. This method permits us to define the additional structure of a
bilinear differential cup product on this sequence, satisfying a Leibniz rule
up to curvature terms. It is not associative, but is part of an A-infinity
algebra of multilinear differential operators, which we also obtain explicitly.
We illustrate the construction in the case of conformal differential geometry,
where the cup product provides a wide-reaching generalization of helicity
raising and lowering for conformally invariant field equations.

</DOC>
<DOC>
<DOCNO> 9671 </DOCNO>
Subdiffusive fluctuations of "pulled" fronts with multiplicative noise


  We study the propagation of a ``pulled'' front with multiplicative noise that
is created by a local perturbation of an unstable state. Unlike a front
propagating into a metastable state, where a separation of time scales for
sufficiently large $t$ creates a diffusive wandering of the front position
about its mean, we predict that for so-called pulled fronts, the fluctuations
are subdiffusive with root mean square wandering $\Delta(t) \sim t^{1/4}$, {\em
not} $t^{1/2}$. The subdiffusive behavior is confirmed by numerical
simulations: For $t \le 600$, these yield an effective exponent slightly larger
than 1/4.

</DOC>
<DOC>
<DOCNO> 122254 </DOCNO>
Gamma-Ray Bursts: Astronomical Constraints


  After presenting a short history of gamma-ray burst (GRB) studies, we discuss
the current constraints on GRB models which follows from astronomical
observations. We concentrate on the energetics of the GRBs with known redshifts
and the association of the well-localized GRBs with star forming regions in
remote galaxies. We also discuss implications of the observed GRB rate.
Arguments are given favoring possible connection of GRBs with core collapse of
massive Wolf-Rayet stars. The possibility of GRB to be a transient phenomenon
in the early history of galactic star formation related to evolution of very
massive metal-free stars is briefly outlined.

</DOC>
<DOC>
<DOCNO> 118320 </DOCNO>
Constraining reionization using the thermal history of the baryons


  The thermal evolution of the intergalactic medium (IGM) depends on the
reionization history of the universe. Numerical simulations indicate that the
low density IGM, which is responsible for the low column density Ly-alpha
forest, follows a well defined temperature-density relation. This results in a
cut-off in the distribution of line widths as a function of column density. We
use hydrodynamic simulations to calibrate the relation between the cut-off and
the temperature-density relation and apply this relation to Keck spectra
spanning a redshift range z=2-4.5. We find that the temperature peaks at z~3
and interpret this as evidence for reheating due to the reionization of helium.

</DOC>
<DOC>
<DOCNO> 13061 </DOCNO>
Magnetoresistance in High-Tc Superconductors: The Role of Vertex


  In high-Tc cuprates, the orbital magnetoresistance in plane (MR,
$\Delta\rho/\rho$) is anomalously enhanced at lower tempemeratures compared
with conventional Fermi liquids, and thus Kohler's rule is strongly violated.
Moreover, it should be noted that an intimate relation between the MR and the
Hall coefficient ($R_H$), $\Delta\rho/\rho \propto (R_H/\rho)^2$, holds well
experimentally, and is called the "modified Kohler's rule". In this letter, we
study this long-standing problem in terms of the nearly antiferromagnetic (AF)
Fermi liquid. We analyze the exact expression for the MR by including the
vertex corrections (VC's) to keep the conservation laws, and find the
approximate "scaling relation" $\Delta\rho/\rho \propto \xi_{AF}^4 /\rho^2$
($\xi_{AF}$ being the AF correlation length.) in the presence of AF
fluctuations. The factor $\xi_{AF}^4$, which comes from the VC's for the
current, gives the additional temperature dependence. By taking account of the
relation $R_H \propto \xi_{AF}^2$ [Kontani et al., PRB 59 (1999) 14723.], we
can naturally explain the modified Kohler's rule. In conclusion, based on the
Fermi liquid theory, the famous {\it seemingly} non-Fermi liquid behaviors of
the Hall coefficient and the MR in high-Tc cuprates are naturally understood on
an equal footing.

</DOC>
<DOC>
<DOCNO> 174493 </DOCNO>
Direct Photon Production in 158 A GeV 208Pb + 208Pb collisions


  A measurement of direct photon production in 208Pb + 208Pb collisions at 158
A GeV has been carried out in the CERN WA98 experiment. The invariant yield or
upper limit of direct photons as a function of transverse momentum in the
interval 0.5 < p_T < 4 GeV/c is presented. A significant direct photon excess
is observed at p_T > 1.5 GeV/c in central collisions. The results are compared
to proton-induced results and to theoretical predictions. Implications for the
dynamics of high-energy heavy-ion collisions are discussed.

</DOC>
<DOC>
<DOCNO> 83188 </DOCNO>
How to Evaluate your Question Answering System Every Day and Still Get


  In this paper, we report on Qaviar, an experimental automated evaluation
system for question answering applications. The goal of our research was to
find an automatically calculated measure that correlates well with human
judges' assessment of answer correctness in the context of question answering
tasks. Qaviar judges the response by computing recall against the stemmed
content words in the human-generated answer key. It counts the answer correct
if it exceeds agiven recall threshold. We determined that the answer
correctness predicted by Qaviar agreed with the human 93% to 95% of the time.
41 question-answering systems were ranked by both Qaviar and human assessors,
and these rankings correlated with a Kendall's Tau measure of 0.920, compared
to a correlation of 0.956 between human assessors on the same data.

</DOC>
<DOC>
<DOCNO> 116718 </DOCNO>
Sub-dekahertz ultraviolet spectroscopy of 199Hg+


  Using a laser that is frequency-locked to a Fabry-Perot etalon of high
finesse and stability, we probe the 5d10 6s 2S_1/2 (F=0) - 5d9 6s 2D_5/2 (F=2)
Delta-m_F = 0 electric-quadrupole transition of a single laser-cooled 199Hg+
ion stored in a cryogenic radio-frequency ion trap. We observe
Fourier-transform limited linewidths as narrow as 6.7 Hz at 282 nm (1.06 X
10^15 Hz), yielding a line Q = 1.6 X 10^14. We perform a preliminary
measurement of the 5d9 6s2 2D_5/2 electric-quadrupole shift due to interaction
with the static fields of the trap, and discuss the implications for future
trapped-ion optical frequency standards.

</DOC>
<DOC>
<DOCNO> 7803 </DOCNO>
Superconductivity in a Mesoscopic Double Square Loop: Effect of


  We have generalized the network approach to include the effects of
short-range imperfections in order to analyze recent experiments on mesoscopic
superconducting double loops. The presence of weakly scattering imperfections
causes gaps in the phase boundary $B(T)$ or $\Phi(T)$ for certain intervals of
$T$, which depend on the magnetic flux penetrating each loop. This is
accompanied by a critical temperature $T_c(\Phi)$, showing a smooth transition
between symmetric and antisymmetric states. When the scattering strength of
imperfections increases beyond a certain limit, gaps in the phase boundary
$T_c(B)$ or $T_c(\Phi)$ appear for values of magnetic flux lying in intervals
around half-integer $\Phi_0=hc/2e$. The critical temperature corresponding to
these values of magnetic flux is determined mainly by imperfections in the
central branch. The calculated phase boundary is in good agreement with
experiment.

</DOC>
<DOC>
<DOCNO> 101534 </DOCNO>
Multiscale Representations for Solutions of Vlasov-Maxwell Equations for


  We present the applications of variational--wavelet approach for computing
multiresolution/multiscale representation for solution of some approximations
of Vlasov-Maxwell equations.

</DOC>
<DOC>
<DOCNO> 152242 </DOCNO>
Statistics of the Composite System


  The space-like asymptotic limit of the bilocal composite field of the state
consisting of a nucleus and an electron is studied. It is shown that the
resulting local field of an atom satisfies the proper commutation relations in
the sub-Fock-space of the atom.

</DOC>
<DOC>
<DOCNO> 70463 </DOCNO>
Consequences of a Z_2 Symmetry for Neutrino Oscillation


  A $Z_{2L}\times Z_{2R}$ generation symmetry in the neutrino sector predicts
the atmospheric neutrino mixing to be maximal, and the MNS matrix element
$U_{e3}$ to be zero, consistent with observations. Solar neutrino mixing may be
maximal but is not required by the symmetry. Neutrino masses of the first two
generations are predicted to vanish, providing a first approximation to the
oscillation data. The consequence of a smaller $Z_2$ symmetry is also
discussed. In that case, deviation from the $Z_{2L}\times Z_{2R}$ result is of
the order of the neutrino mass ratio between the first two generations and the
third generation.

</DOC>
<DOC>
<DOCNO> 85409 </DOCNO>
Symmetry, Singularities and Integrability in Complex Dynamics IV:


  We apply the results of singularity analysis to the isotropic cosmological
models in general relativity and string theory with a variety of matter terms.
For some of these models the standard Painlev\'{e} test is sufficient to
demonstrate integrability or nonintegrability in the sense of Painlev\'{e}. For
others of these models it is necessary to use a less algorithmic procedure.

</DOC>
<DOC>
<DOCNO> 68017 </DOCNO>
Adiabatic CDM Models and the Competition


  The inflation-inspired flat, cold dark matter-dominated models of structure
formation with adiabatic, nearly scale-invariant initial conditions agree very
well with current CMB anisotropy data. The success of these models is
highlighted by the failure of alternatives; we argue that there are no longer
any viable competitors (with the exception of models with more complicated
matter content which are still flat and which still require inflation). CMB
data will soon be of sufficient quality that, if one {\it assumes} inflation,
one can detect a non-zero cosmological constant by combining a determination of
the peak location with Hubble constant measurements.

</DOC>
<DOC>
<DOCNO> 12203 </DOCNO>
Soft tetragonal distortions in ferromagnetic Ni_2MnGa and related


  A detailed examination of the energy landscape, density of states and
magnetic moment of tetragonally distorted ferromagnetic Ni_2MnGa was performed
using first-principles local-spin-density (LSD) pseudopotential calculations,
varying V as well as c/a. The energy of tetragonal Ni_2MnGa is found to be
nearly constant for values of c/a over a wide range, with shallow minima near
c/a = 1 and 1.08 in addition to that near 1.2. This flat energy surface is
consistent with the wide range of observed values of c/a. It also explains the
observation of pseudomorphic growth of Ni_2MnGa on GaAs, despite a nominal 3%
lattice mismatch. The related materials Ni_2MnAl, Ni_2MnIn and ferromagnetic
NiMn were examined for similar behavior, but all are seen to have a single
well-defined minimum at c/a near 1, consistent with available experimental
information. For NiMn, the ground state antiferromagnetic ordering and
structural parameters are correctly predicted within the LSD approach.

</DOC>
<DOC>
<DOCNO> 84745 </DOCNO>
Locally Sasakian Manifolds


  We show that every Sasakian manifold in dimension $2k+1$ is locally generated
by a free real function of $2k$ variables. This function is a Sasakian analogue
of the K\"ahler potential for K\"ahler geometry. It is also shown that every
locally Sasakian-Einstein manifold in $2k+1$ dimensions is generated by a
locally K\"ahler-Einstein manifold in dimension $2k$.

</DOC>
<DOC>
<DOCNO> 102114 </DOCNO>
Equivariant Deformation Quantization for the Cotangent Bundle of a Flag


  Let $\XR$ be a (generalized) flag manifold of a non-compact real semisimple
Lie group $\GR$, where $\XR$ and $\GR$ have complexifications X and G. We
investigate the problem of constructing a graded star product on $Pol(T^*\XR)$
which corresponds to a $\GR$-equivariant quantization of symbols into smooth
differential operators acting on half-densities on $\XR$.
  We show that any solution is algebraic in that it restricts to a
G-equivariant graded star product star on the algebraic part R of
$Pol(T^*\XR)$. We construct, when R is generated by the momentum functions
$\mu^x$ for G, a preferred choice of star where $\mu^x\star\phi$ has the form
$\mu^x\phi+\half\{\mu^x,\phi\}t+\Lambda^x(\phi)t^2$. Here $\Lambda^x$ are
operators on R which are not differential in the known examples and so
$\mu^x\star\phi$ is not local in $\phi$.
  R acquires an invariant positive definite inner product compatible with its
grading. The completion of R is a new Fock space type model of the unitary
representation of G on $L^2$ half-densities on X.

</DOC>
<DOC>
<DOCNO> 12583 </DOCNO>
Statistical Physics Approach to M-theory Integrals


  We explain the concepts of computational statistical physics which have
proven very helpful in the study of Yang-Mills integrals, an ubiquitous new
class of matrix models. Issues treated are: Absolute convergence versus Monte
Carlo computability of near-singular integrals, singularity detection by
Markov-chain methods, applications to asymptotic eigenvalue distributions and
to numerical evaluations of multiple bosonic and supersymmetric integrals. In
many cases already, it has been possible to resolve controversies between
conflicting analytical results using the methods presented here.

</DOC>
<DOC>
<DOCNO> 122327 </DOCNO>
Studying the Galactic Bulge Through Spectroscopy of Microlensed Sources:


  The observed spectra of the microlensed sources towards the Galactic bulge
may be used as a tool for studying the kinematics and extinction effects in the
Galactic bulge. In this paper, we first investigate the expected distribution
of the microlensed sources as a function of depth within the Galactic bulge.
Our analysis takes a magnitude limited microlensing survey into account, and
includes the effects of extinction. We show that, in the current magnitude
limited surveys, the probability that the source lies at the far side of the
bulge is larger than the probability that the source lies at the near side by a
factor of about 2--4. We then investigate the effects of extinction on the
observed spectra of microlensed sources. Kurucz model spectra and the observed
extinctions towards the Galactic bulge have been used to demonstrate that the
microlensed sources should clearly show the effects of extinction which, in
turn, can be used as a statistical measure of the contribution of the disk
lenses and bulge lenses at different depths. The spectra of the microlensed
sources provide a unique probe to derive the radial velocities of a sample
which lies preferentially at the far side of the Galactic bulge. The radial
velocities, coupled with the microlensing time scales, can thus be useful in
studying the 3-dimensional kinematics of the Galactic bulge.

</DOC>
<DOC>
<DOCNO> 69269 </DOCNO>
Lambda polarization in pp -> p\Lambda K^+ \pi^+\pi^-\pi^+\pi^-


  We show that there is a correlation between the invariant mass of the
produced \Lambda K^+, \Lambda K^+\pi^+\pi^- or \Lambda K^+ \pi^+\pi^-\pi^+\pi^-
system in the exclusive reaction pp\to p\Lambda K^+\pi^+\pi^-\pi^+\pi^- and the
longitudinal or transverse momentum of $\Lambda$. Together with the
longitudinal and transverse momentum dependence of Lambda polarization observed
in inclusive reactions, such a correlation implies a dependence of Lambda
polarization on these invariant masses. The qualitative features of this
dependence are consistent with the recent observation by E766 collaboration at
BNL. A quantitative estimation has been made using an event generator for $pp$
collisions. A detailed comparison with the data is made.

</DOC>
<DOC>
<DOCNO> 9453 </DOCNO>
Random networks created by biological evolution


  We investigate a model of evolving random network, introduced by us
previously {[}{\it Phys. Rev. Lett.} {\bf 83}, 5587 (1999){]} . The model is a
generalization of the Bak-Sneppen model of biological evolution, with the
modification that the underlying network can evolve by adding and removing
sites. The behavior and the averaged properties of the network depend on the
parameter $p$, the probability to establish link to the newly introduced site.
For $p=1$ the system is self-organized critical, with two distinct power-law
regimes with forward-avalanche exponents $\tau=1.98\pm 0.04$ and $\tau^\prime =
1.65\pm 0.05$. The average size of the network diverge as power-law when $p\to
1$. We study various geometrical properties of the network: probability
distribution of sizes and connectivities, size and number of disconnected
clusters and the dependence of mean distance between two sites on the cluster
size. The connection with models of growing networks with preferential
attachment is discussed.

</DOC>
<DOC>
<DOCNO> 151449 </DOCNO>
Logarithmic two dimensional spin-1/3 fractional supersymmetric conformal


  Logarithmic spin-1/3 superconformal field theories are investigated. the
chiral and full two-point functions of two-(or more-) dimensional Jordanian
blocks of arbitrary weights, are obtained.

</DOC>
<DOC>
<DOCNO> 150992 </DOCNO>
Brane World Inflation Induced by Quantum Effects


  We consider brane-world universe where an arbitrary large $N$ quantum CFT is
living on the domain wall. This corresponds to implementing of Randall-Sundrum
compactification within the context of AdS/CFT correspondence. Using anomaly
induced effective action for domain wall CFT the possibility of self-consistent
quantum creation of 4d de Sitter wall Universe (inflation) is demonstrated. In
case of maximally SUSY Yang-Mills theory the exact correspondence with radius
and effective tension found by Hawking-Hertog-Reall is obtained. The hyperbolic
wall Universe may be induced by quantum effects only for exotic matter (higher
derivatives conformal scalar) which has unusual sign of central charge.

</DOC>
<DOC>
<DOCNO> 83416 </DOCNO>
Towards rule-based visual programming of generic visual systems


  This paper illustrates how the diagram programming language DiaPlan can be
used to program visual systems. DiaPlan is a visual rule-based language that is
founded on the computational model of graph transformation. The language
supports object-oriented programming since its graphs are hierarchically
structured. Typing allows the shape of these graphs to be specified recursively
in order to increase program security. Thanks to its genericity, DiaPlan allows
to implement systems that represent and manipulate data in arbitrary diagram
notations. The environment for the language exploits the diagram editor
generator DiaGen for providing genericity, and for implementing its user
interface and type checker.

</DOC>
<DOC>
<DOCNO> 100682 </DOCNO>
Discrete torsion and twisted orbifold cohomology


  In this article, we study the twisting procedure of orbifold cohomology. We
introduce local system and construct twisted orbifold cohomology. Then, we
generalize Vafa-Witten's notion of discrete torsion to general orbifold and
examine its relation to local system. Finally, some examples are computed.

</DOC>
<DOC>
<DOCNO> 101781 </DOCNO>
Combinatorics of geometrically distributed random variables: Value and


  For words of length n, generated by independent geometric random variables,
we consider the average value and the average position of the r-th
left-to-right maximum counted from the right, for fixed r and n->oo. This
complements previous research where the analogous questions were considered for
the r-th left-to-right maximum counted from the left.

</DOC>
<DOC>
<DOCNO> 121115 </DOCNO>
The Principal Axis of the Virgo Cluster


  Using accurate distances to individual Virgo cluster galaxies obtained by the
method of Surface Brightness Fluctuations, we show that Virgo's brightest
ellipticals have a remarkably collinear arrangement in three dimensions. This
axis, which is inclined by 10 to 15 degrees from the line of sight, can be
traced to even larger scales where it appears to join a filamentary bridge of
galaxies connecting Virgo to the rich cluster Abell 1367. The orientations of
individual Virgo ellipticals also show some tendency to be aligned with the
cluster axis, as does the jet of the supergiant elliptical M87. These results
suggest that the formation of the Virgo cluster, and its brightest member
galaxies, have been driven by infall of material along the Virgo-A1367
filament.

</DOC>
<DOC>
<DOCNO> 99794 </DOCNO>
Some Comments on Categories, Particles and Interactions


  An algebraic formalism for the study of interacting particle systems is
developed. Particle processes are described in terms of the category theory.
The problem for the unique description of these processes is discussed.
Categories relevant for this subject are described. The concept of generalized
transmutations of interacting particle systems is considered. The connection
with a system with some generalized statistics is explained.

</DOC>
<DOC>
<DOCNO> 116898 </DOCNO>
Superconducting Superstructure for the TESLA Collider: New Results


  A new cavity-chain layout has been proposed for the main linac of the TESLA
linear collider. This superstructure-layout is based upon four 7-cell
superconducting standing-wave cavities, coupled by short beam pipes. The main
advantages of the superstructure are an increase in the active accelerating
length in TESLA and a saving in rf components, especially power couplers, as
compared to the present 9-cell cavities. The proposed scheme allows to handle
the field-flatness tuning and the HOM damping at sub-unit level, in contrast to
standard multi-cell cavities. The superstructure-layout is extensively studied
at DESY since 1999. Computations have been performed for the rf properties of
the cavity-chain, the bunch-to-bunch energy spread and multibunch dynamics. A
copper model of the superstructure has been built in order to compare with the
simulations and for testing the field-profile tuning and the HOM damping
scheme. A "proof of principle" niobium prototype of the superstructure is now
under construction and will be tested with beam at the TESLA Test Facility in
2001. In this paper we present latest results of these investigations.

</DOC>
<DOC>
<DOCNO> 72022 </DOCNO>
Angular distributions in hard exclusive production of pion pairs


  Using the leading order amplitudes of hard exclusive electroproduction of
pion pairs we have analyzed the angular distribution of the two produced
particles. At leading twist a pion pair can be produced only in an isovector or
an isoscalar state. We show that certain components of the angular distribution
only get contributions from the interference of the I=1 and the (much smaller)
I=0 amplitude. Therefore our predictions prove to be a good probe of isospin
zero pion pair production. We predict effects of a measurable size that could
be observed at experiments like HERMES. We also discuss how hard exclusive pion
pair production can provide us with new information on the effective chiral
Lagrangian.

</DOC>
<DOC>
<DOCNO> 70668 </DOCNO>
Behavior of the thermal gluon self-energy in the Coulomb gauge


  We study, to one loop order, the behavior of the gluon self-energy in the non
covariant Coulomb gauge at finite temperature. The cancellation of the peculiar
energy divergences, which arise in such a gauge, is explicitly verified in the
complete two point function of the Yang-Mills theory. At high temperatures, the
leading T^2 term is determined to be transverse and nonlocal, in agreement with
the results obtained in covariant gauges. The coefficient of the sub-leading
ln(T) contribution, is non transverse but local and coincides (up to a
multiplicative constant) with that of the ultraviolet pole term of the zero
temperature amplitude.

</DOC>
<DOC>
<DOCNO> 14121 </DOCNO>
Rheology of Semi-dilute Solutions of Calf-thymus DNA


  We study the rheology of semi-dilute solutions of the sodium salt of
calf-thymus DNA in the linear and nonlinear regimes. The frequency response
data can be fitted very well to the hybrid model with two dominant relaxation
times $\tau_{\circ}$ and $\tau_{1}$. The ratio $\frac{\tau_{\circ}}{\tau_{1}}
\sim$ 5 is seen to be fairly constant on changing the temperature from
20$^{\circ}$C to 30$^{\circ}$C. The shear rate dependence of viscosity can be
fitted to the Carreau model.

</DOC>
<DOC>
<DOCNO> 178498 </DOCNO>
Hot nuclear matter in the modified quark-meson coupling model with


  Short-range quark-quark correlations in hot nuclear matter are examined
within the modified quark-meson coupling model (MQMC) by adding repulsive
scalar and vector quark-quark interactions. Without these correlations, the bag
radius increases with the baryon density. However when the correlations are
introduced the bag size shrinks as the bags overlap. Also as the strength of
the scalar quark-quark correlation is increased, the decrease of the effective
nucleon mass $M^{*}_N$ with the baryonic density is slowed down and tends to
saturate at high densities. Within this model we study the phase transition
from the baryon-meson phase to the quark-gluon plasma (QGP) phase with the
latter modeled as an ideal gas of quarks and gluons inside a bag. Two models
for the QGP bag parameter are considered. In one case, the bag is taken to be
medium-independent and the phase transition from the hadron phase to QGP is
found to occur at 5-8 times ordinary nuclear matter density for temperatures
less than 60 MeV. For lower densities, the transition takes place at higher
temperature reaching up to 130 MeV at zero density. In the second case, the QGP
bag parameter is considered medium-dependent as in the MQMC model for the
hadronic phase. In this case, it is found that the phase transition occurs at
much lower densities.

</DOC>
<DOC>
<DOCNO> 69729 </DOCNO>
A note on the RG flow in (N=1, D=4) Supergravity and applications to Z_3


  We apply the standard approach of RG flow for the gauge couplings in N=1 D=4
Supergravity to show how to match its results with the heterotic $Z_3$ orbifold
and Type IIB ${Z_3}$ orientifold-based models. Using only supergravity, anomaly
cancellation and the requirement of unification we determine the part of the
K\"ahler potential of the model invariant under the symmetries of the model.
For heterotic orbifolds/type IIB orientifolds, this shows that the lowest order
K\"ahler term of the dilaton has the structure $-\ln(S+{\bar S})$ in agreement
with string calculations. The structure of the holomorphic coupling is also
found from arguments of unification and anomaly cancellation under the
conjectured $SL(2,Z)_{T_i}$ symmetries of the models. A consequence of the
latter is that in the case of the $Z_3$ orientifold the holomorphic coupling
necessarily contains a part with coefficient proportional to the one loop beta
function, in agreement with string calculations which do not however assume
this symmetry. This gives circumstantial evidence for the existence of this
symmetry at string level in $Z_3$ orientifold. Finally, we comment on the
values of the unification scale and examine the possibility of mirage
unification in which the effective unification scale may be situated far above
the string scale.

</DOC>
<DOC>
<DOCNO> 12105 </DOCNO>
Force distributions in 3D granular assemblies: Effects of packing order


  We present a systematic investigation of the distribution of normal forces at
the boundaries of static packings of spheres. A new method for the efficient
construction of large hexagonal-close-packed crystals is introduced and used to
study the effect of spatial ordering on the distribution of forces. Under
uniaxial compression we find that the form for the probability distribution of
normal forces between particles does not depend strongly on crystallinity or
inter-particle friction. In all cases the distribution decays exponentially at
large forces and shows a plateau or possibly a small peak near the average
force but does not tend to zero at small forces.

</DOC>
<DOC>
<DOCNO> 100375 </DOCNO>
On Characters of Weyl Groups


  In this note a combinatorial formula related to the symmetric group is
generalized to an arbitrary finite Weyl group.

</DOC>
<DOC>
<DOCNO> 70906 </DOCNO>
Search for QCD-instanton-induced effects in deep inelastic electron


  After summarizing the results of QCD-instanton-perturbation theory for the
calculation of instanton-induced effects in deep inelastic electron proton
scattering, we discuss search strategies for instanton-induced effects that
have been derived for HERA-conditions using the QCDINS-Monte Carlo. Recent
results from the H1 collaboration are presented.

</DOC>
<DOC>
<DOCNO> 118500 </DOCNO>
The mass surface density in the local disk and the chemical evolution of


  We have studied the effect of adopting different values of the total baryonic
mass surface density in the local disk at the present time in a model for the
chemical evolution of the Galaxy. We have compared our model results with the
G-dwarf metallicity distribution, the amounts of gas, stars, stellar remnants,
infall rate and SN rate in the solar vicinity, and with the radial abundance
gradients and gas distribution in the disk. This comparison strongly suggests
that the value of the total baryonic mass surface density in the local disk
which best fits the observational properties should lie in the range 50-75 Msun
pc-2, and that values outside this range should be ruled out.

</DOC>
<DOC>
<DOCNO> 12090 </DOCNO>
Kinetic pathways of multi-phase surfactant systems


  The relaxation following a temperature quench of two-phase (lamellar and
sponge phase) and three-phase (lamellar, sponge and micellar phase) samples,
has been studied in an SDS/octanol/brine system. In the three-phase case we
have observed samples that are initially mainly sponge phase with lamellar and
micellar phase on the top and bottom respectively. Upon decreasing temperature
most of the volume of the sponge phase is replaced by lamellar phase. During
the equilibriation we have observed three regimes of behaviour within the
sponge phase: (i) disruption in the sponge texture, then (ii) after the sponge
phase homogenises there is a lamellar nucleation regime and finally (iii) a
bizarre plume connects the lamellar phase with the micellar phase. The
relaxation of the two-phase sample proceeds instead in two stages. First
lamellar drops nucleate in the sponge phase forming a onion `gel' structure.
Over time the lamellar structure compacts while equilibriating into a two phase
lamellar/sponge phase sample. We offer possible explanatioins for some of these
observations in the context of a general theory for phase kinetics in systems
with one fast and one slow variable.

</DOC>
<DOC>
<DOCNO> 85273 </DOCNO>
Distorted Black Holes with Charge


  We present new solutions to the Einstein-Maxwell equations representing a
class of charged distorted black holes. These solutions are static-axisymmetric
and are generalizations of the distorted black hole solutions studied by Geroch
and Hartle. Physically, they represent a charged black hole distorted by
external matter fields. We discuss the zeroth and first law for these black
holes. The first law is proved in two different forms, one motivated by the
isolated horizon framework and the other using normalizations at infinity.

</DOC>
<DOC>
<DOCNO> 40236 </DOCNO>
The Supersymmetry Soft-breaking Lagrangian - Where Experiment and String


  After an introduction recalling that we expect low energy supersymmetry to be
part of our description of nature because of considerable indirect evidence and
successful predictions, and a discussion of the essential role of data for
formulating and testing string theory, these lectures focus on the role of the
supersymmetry soft-breaking Lagrangian in connecting experiment and string
theory. How to measure tan$\beta$ and the soft parameters is examined via a
number of applications, and the difficulty of measuring tan$\beta$ at hadron
colliders is explained. In each case the important role of soft phases is made
explicit, and the true number of parameters is counted. Applications include
the chargino and neutralino sectors, the Higgs sector and how its results
change when phases are included, measuring the (relative) gluino phase, CP
violation in K and B systems and whether all CP violation can be due to soft
phases, how to learn if the LSP is the cold dark matter of the universe, and
baryogenesis. It is emphasized that the success of supersymmetry in explaining
the breaking of electroweak symmetry is probably its most important
achievement, and implications of that explanation for superpartner masses are
shown. Combining many of these considerations, a further application argues
that a lepton collider of total energy 600 GeV with a polarized beam is one we
can be confident will do important physics even after LHC. The question of the
origins of CP violation, whether the CKM phase can be zero, and the possibility
that the soft phases can tell us about compactification and supersymmetry
breaking are discussed. Some of the applications and issues are examined in a
D-brane based model that can describe the usual collider and dark matter
phenomenology, and includes phases and CP violation as well.

</DOC>
<DOC>
<DOCNO> 118639 </DOCNO>
Evidence for topological nonequilibrium in magnetic configurations


  We use direct numerical simulations to study the evolution, or relaxation, of
magnetic configurations to an equilibrium state. We use the full single-fluid
equations of motion for a magnetized, non-resistive, but viscous fluid; and a
Lagrangian approach is used to obtain exact solutions for the magnetic field.
As a result, the topology of the magnetic field remains unchanged, which makes
it possible to study the case of topological nonequilibrium. We find two cases
for which such nonequilibrium appears, indicating that these configurations may
develop singular current sheets.

</DOC>
<DOC>
<DOCNO> 117060 </DOCNO>
Dirac and Majorana Constructs


  The present work is a brief review of the recent development in the
relativistic quantum mechanics in the $(1/2)\oplus (0,1/2)$ representation
space. It can be useful for graduate students in particle physics and quantum
field theory.

</DOC>
<DOC>
<DOCNO> 40435 </DOCNO>
Fermilab E791


  Fermilab E791, a very high statistics charm particle experiment, recently
completed its data taking at Fermilab's Tagged Photon Laboratory. Over 20
billion events were recorded through a loose transverse energy trigger and
written to 8mm tape in the the 1991-92 fixed target run at Fermilab. This
unprecedented data sample containing charm is being analysed on many-thousand
MIP RISC computing farms set up at sites in the collaboration. A glimpse of the
data taking and analysis effort is presented. We also show some preliminary
results for common charm decay modes. Our present analysis indicates a very
rich yield of over 200K reconstructed charm decays.

</DOC>
<DOC>
<DOCNO> 150994 </DOCNO>
Properties of the massive Thirring model from the XYZ spin chain


  We consider here the massive Thirring model regularized with the XYZ spin
chain. We numerically calculate the mass ratios of particles which lie in the
discrete part of the spectrum and obtain results in accordance with the DHN
formula and in disagreement with recent calculations in the literature based on
the numerical Bethe ansatz and infinite momentum frame methods. We also analyze
the short distance behavior of these states and evaluate the conformal
dimensions. This paper, taken together with the previous one for the
sine-Gordon model, confirms the duality relation between two models formulated
by Klassen and Melzer [Int. J. Mod. Phys. A 8, 4131 (1993)].

</DOC>
<DOC>
<DOCNO> 9784 </DOCNO>
Topological Defects and the Spin Glass Phase of Cuprates


  We propose that the spin glass phase of cuprates is due to the proliferation
of topological defects of a spiral distortion of the antiferromagnet order. Our
theory explains straightforwardly the simultaneous existence of short range
incommensurate magnetic correlations and complete a-b symmetry breaking in this
phase. We show via a renormalization group calculation that the collinear
O(3)/O(2) symmetry is unstable towards the formation of local non-collinear
correlations. A critical disorder strength is identified beyond which
topological defects proliferate already at zero temperature.

</DOC>
<DOC>
<DOCNO> 13948 </DOCNO>
Forced Rayleigh Scattering Studies of Tracer Diffusion in a Nematic


  We have employed forced Rayleigh scattering (FRS) to study the diffusion of
an azo tracer molecule (methyl red) through a nematic liquid crystal (5CB).
This system was first investigated in an important study by Hara et al. (Japan.
J. Appl. Phys. 23, 1420 [1984]). Since that time, it has become clear that the
presence of complementary ground-state and photoproduct FRS gratings can result
in nonexponential profiles, and that complementary-grating effects are
significant even when "minor" deviations from exponential decay are observed.
We have investigated the methyl red/5CB system in order to evaluate the
possible effects of complementary gratings. In the isotropic phase, we find
that the presence of complementary gratings results in a nonmonotonic FRS
signal, which significantly changes the values inferred for the isotropic
diffusion coefficients. As a result, the previously reported discontinuity at
the nematic/isotropic transition temperature (TNI) is not present in the new
data. On the other hand, in the nematic phase, the new experiments largely
confirm the previous observations of single-exponential FRS decay and the
non-Arrhenius temperature dependence of the nematic diffusion coefficients
close to TNI. Finally, we have also observed that the decrease in the diffusion
anisotropy with increasing temperature can be correlated with the 5CB nematic
order parameter S(T) over the full nematic temperature range.

</DOC>
<DOC>
<DOCNO> 116415 </DOCNO>
Time-Reversed Diffraction


  We show that a time-reversed formulation of Huygens-Kirchhoff diffraction can
be used to deduce the transverse and longitudinal fields of a Gaussian laser
beam, starting from a simple assumption of a Gaussian beam profile in the far
field. An attempt to apply this technique to the far fields of a Hertzian
dipole shows how the laws of diffraction do not permit a wave to be focused to
a volume smaller than a cubic wavelength in a charge-free region.

</DOC>
<DOC>
<DOCNO> 151598 </DOCNO>
Inconsistency of interacting, multi-graviton theories


  We investigate, in any spacetime dimension >=3, the problem of consistent
couplings for a finite collection of massless, spin-2 fields described, in the
free limit, by a sum of Pauli-Fierz actions. We show that there is no
consistent (ghost-free) coupling, with at most two derivatives of the fields,
that can mix the various "gravitons". In other words, there are no
Yang-Mills-like spin-2 theories. The only possible deformations are given by a
sum of individual Einstein-Hilbert actions. The impossibility of
cross-couplings subsists in the presence of scalar matter. Our approach is
based on the BRST-based deformation point of view and uses results on the
so-called "characteristic cohomology" for massless spin-2 fields which are
explained in detail.

</DOC>
<DOC>
<DOCNO> 84317 </DOCNO>
Belinskii-Zakharov Formulation for Bianchi models and Painleve III


  We show that \a < 0, \b > 0, \g=\d=0 Painleve III equation arises as a
zero-curvature condition in the Belinskii-Zakharov inverse-scattering
formulation for Bianchi cosmological models. For special values of the
parameters this Painleve III equation becomes the dynamical equation for
Bianchi I, II, VI_0 and VII_0 models.

</DOC>
<DOC>
<DOCNO> 119240 </DOCNO>
Detecting the First Objects in the Mid-IR with NGST


  We calculate the expected Mid-IR molecular hydrogen line emission from the
first objects in the universe. Due to their low masses, the stellar feedback
from massive stars is able to blowaway their gas content and collect it into a
cooling shell where H_2 rapidly forms and IR roto-vibrational (as for example
the restframe 2.12 micron) lines carry away a large fraction (up to 10%) of the
explosion energy. The fluxes from these sources are in the range
10^{-21}-10^{-17} erg/s/cm^2. The highest number counts are expected in the 20
micron band, where about 10^5 sources/deg^2 are predicted at the limiting flux
of 3 \times 10^{-18} erg/s/cm^2. Among the planned observational facilities, we
find that the best detection perspectives are offered by NGST, which should be
able to reveal about 200 first objects in one hour observation time at its
limiting flux in the above band. Therefore, Mid-IR instruments appear to
represent perfect tools to trace star formation and stellar feedback in the
high (z>5) redshift universe.

</DOC>
<DOC>
<DOCNO> 118425 </DOCNO>
The Nuclear Activity of the Galaxies in the Hickson Compact Groups


  In order to investigate the nuclear activity of galaxies residing in compact
groups of galaxies, we present results of our optical spectroscopic program
made at Okayama Astrophysical Observatory. We have performed optical
spectroscopy of 69 galaxies which belong to 31 Hickson Compact Groups (HCGs) of
Galaxies. Among them, three galaxies have discordant redshifts. Further,
spectral quality is too poor to classify other three galaxies. Therefore, we
describe our results for the remaining 63 galaxies.
  Our main results are summarized below. (1) We have found in our sample; 28
AGN, 16 HII nuclei, and 19 normal galaxies which show no emission line. We used
this HCG sample for statistical analyses. (2) Comparing the frequency
distributions of activity types between the HCGs and the field galaxies whose
data are taken from Ho, Filippenko, & Sargent (382 field galaxies), we find
that the frequency of HII nuclei in the HCGs is significantly less than that in
the field. However, this difference may be due to selection bias that our HCG
sample contains more early-type galaxies than the field, because it is known
that HII nuclei are rarer in early-type galaxies than in later ones. (3)
Applying correction this morphological bias to the HCG sample, we find that
there is no statistically significant difference in the frequency of occurrence
of emission-line galaxies between the HCGs and the field. This implies that the
dense galaxy environment in the HCGs does not affect triggering both the AGN
activity and the nuclear starburst. We discuss some implications on the nuclear
activity in the HCG galaxies.

</DOC>
<DOC>
<DOCNO> 85361 </DOCNO>
Twisting type-N vacuum fields with a group $H_2$


  We derive the equations corresponding to twisting type-N vacuum gravitational
fields with one Killing vector and one homothetic Killing vector by using the
same approach as that developed by one of us in order to treat the case with
two non-commuting Killing vectors. We study the case when the homothetic
parameter $\phi$ takes the value -1, which is shown to admit a reduction to a
third-order real ordinary differential equation for this problem, similar to
that previously obtained by one of us when two Killing vectors are present.

</DOC>
<DOC>
<DOCNO> 72013 </DOCNO>
A different view of deep inelastic electron-proton scattering


  Deep inelastic electron-proton scattering is analyzed in the target rest
frame using a theoretical approach suitable to describe many-body systems of
{\em bound} constituents subject to {\em interactions}. At large three-momentum
transfer $\magq$, this approach predicts the onset of scaling in the variable
$\yt=\nu$-$\magq$, where $\nu$ denotes the energy transfer. The present
analysis shows that the data, plotted at constant $\magq$, exhibit a remarkable
scaling behavior in $\yt$ and manifestly display the presence of sizable
interaction effects.

</DOC>
<DOC>
<DOCNO> 11913 </DOCNO>
Free energy approximations in simple lattice proteins


  This work addresses the question of whether it is possible to define simple
pair-wise interaction terms to approximate free energies of proteins or
polymers. Rather than ask how reliable a potential of mean force is, one can
ask how reliable it could possibly be. In a two-dimensional, infinite lattice
model system one can calculate exact free energies by exhaustive enumeration. A
series of approximations were fitted to exact results to assess the feasibility
and utility of pair-wise free energy terms. Approximating the true free energy
with pair-wise interactions gives a poor fit with little transferability
between systems of different size. Adding extra artificial terms to the
approximation yields better fits, but does not improve the ability to
generalise from one system size to another. Further, one cannot distinguish
folding from non-folding sequences via the approximated free energies. Most
usefully, the methodology shows how one can assess the utility of various terms
in lattice protein/polymer models.

</DOC>
<DOC>
<DOCNO> 118161 </DOCNO>
Nearby Gas-Rich Low Surface Brightness Galaxies


  We examine the Fisher-Tully cz<1000 km/s galaxy sample to determine whether
it is a complete and representative sample of all galaxy types, including low
surface brightness populations, as has been recently claimed. We find that the
sample is progressively more incomplete for galaxies with (1) smaller physical
diameters at a fixed isophote and (2) lower HI masses. This is likely to lead
to a significant undercounting of nearby gas-rich low surface brightness
galaxies. However, through comparisons to other samples we can understand how
the nearby galaxy counts need to be corrected, and we see some indications of
environmental effects that probably result from the local high density of
galaxies.

</DOC>
<DOC>
<DOCNO> 8329 </DOCNO>
Rashba spin splitting in two-dimensional electron and hole systems


  In two-dimensional (2D) hole systems the inversion asymmetry induced spin
splitting differs remarkably from its familiar counterpart in the conduction
band. While the so-called Rashba spin splitting of electron states increases
linearly with in-plane wave vector k_|| the spin splitting of heavy hole states
can be of third order in k_|| so that spin splitting becomes negligible in the
limit of small 2D hole densities. We discuss consequences of this behavior in
the context of recent arguments on the origin of the metal-insulator transition
observed in 2D systems.

</DOC>
<DOC>
<DOCNO> 152603 </DOCNO>
How much can supergravity teach us about microscopic features of BPS


  We review recent results in the study of regular four dimensional BPS black
holes in toroidally compactified type II (or M) theory. We discuss the
generating solution for this kind of black holes, its microscopic
description(s), and compute the corresponding microscopic entropy. These
achievements, which provide a description of the fundamental degrees of freedom
accounting for the entropy of any regular BPS black hole in the theory under
consideration, are inscribed within a research project aimed to the study of
the microscopic properties of this kind of solutions in relation to U--duality
invariants computed on the corresponding macroscopic (supergravity)
description.

</DOC>
<DOC>
<DOCNO> 121351 </DOCNO>
Irradiated Herbig-Haro Jets in the Orion Nebula and Near NGC 1333


  We report the discovery of a dozen Herbig-Haro jets illuminated by the Lyman
continuum and/or softer far-ultraviolet radiation fields of nearby high mass
stars. Five irradiated outflows lie in the outer parts of the Orion Nebula and
seven lie near the reflection nebula NGC 1333 in the Perseus molecular cloud.
We propose that the UV radiation field has eroded residual material left over
from the formation of these young source stars. Many of the irradiated jets
exhibit unusual C-shaped bending. In the outskirts of the Orion Nebula, most
irradiated jets bend away from the core of the nebula. On the other hand, in
NGC 1333, the C-shaped jets bend back towards the cluster center. Jet bending
in the Orion Nebula may be dominated by either the outflow of material from the
nebular core or by the rocket effect pushing on the irradiated portion of a
mostly neutral jet beam. But in NGC 1333, jet bending may indicate that the
source stars have been ejected from the cluster core. Many irradiated jets are
asymmetric with one beam much brighter than the other. When fully
photo-ionized, irradiated jets may provide unique insights into the physical
conditions within outflows powered by young stars, permitting the determination
of the density and location of stellar ejecta even in the absence of shocks. We
present a model for the photo-ionization of these outflows by external
radiation fields and discuss possible mechanisms for producing the observed
asymmetries. We demonstrate that the UV radiation field may alter the amount of
cloud material entrained by the jet. We also report the discovery of some large
scale bow shocks which face the core of the Orion Nebula and which surround
visible young stars. These wind-wind collision fronts provide further evidence
for a large scale mass flow originating near the nebular core.

</DOC>
<DOC>
<DOCNO> 121961 </DOCNO>
The Arecibo Dual-Beam Survey: Filling the Gap in the Extragalactic


  We present the Arecibo Dual-Beam Survey (ADBS), a "blind" 21cm survey for
galaxies. The ADBS is the largest to date with the Arecibo radio telescope. We
were able to achieve an rms sensitivity of 3-4 mJy in only 7 seconds. The ADBS
covers substantially more volume than the Spitzak & Schneider (1998) and the
Zwaan et al. (1997) surveys. It is surpassed by the Parkes HIPASS survey
(Kilborn et al. 1999) but has much better angular resolution and sensitivity.
We will discuss the HI sample and our efforts to quantify the completeness and
reliability.
  This is the first survey to use synthetic sources to establish the relation
between the flux, line width, and completeness of the survey. An empirical
understanding of these quantities is vital to the determination of the mass
function. Even if we do not understand all of the reasons why we do not detect
galaxies, the empirical understanding allows us to account for them properly.
  In addition to the more general discussion of the ADBS survey, we will
discuss galaxies which have large ratios of HI mass to optical area and
probably have extended HI disks. We detect a much higher percentage of these
high HI mass to optical area galaxies than are seen in optical surveys
indicating that optical surveys miss these galaxies. Among these galaxies are
also 7 galaxies with HI masses < 10^8 M_sun. Based on the mass function of
Schneider & Rosenberg (this volume), the low mass galaxies are an important
part of the general galaxy population.

</DOC>
<DOC>
<DOCNO> 69731 </DOCNO>
On the range of validity of the parton model


  Based on the world DIS data we extract $F_2^p - F_2^n$ as a function of
Bjorken $x$ and photon virtuality $Q^2$. The standard PDFs fail to describe the
experimental data below $Q^2 <$ 7 GeV$^2$. The trend of the data is
approximately explained by our recent model.

</DOC>
<DOC>
<DOCNO> 11187 </DOCNO>
Electronic transport through ballistic chaotic cavities: reflection


  We extend previous studies on transport through ballistic chaotic cavities
with spatial left-right (LR) reflection symmetry to include the presence of
direct processes. We first analyze fully LR-symmetric systems in the presence
of direct processes and compare the distribution w(T) of the transmission
coefficient T with that for an asymmetric cavity with the same "optical" S
matrix. We then study the problem of "external mixing" of the symmetry caused
by an asymmetric coupling of the cavity to the outside. We first consider the
case where symmetry breaking arises because two symmetrically positioned
waveguides are coupled to the cavity by means of asymmetric tunnel barriers.
Although this system is asymmetric with respect to the LR operation, it has a
striking memory of the symmetry of the cavity it was constructed from.
Secondly, we break LR symmetry in the absence of direct proceses by
asymmetrically positioning the two waveguides and compare the results with
those for the completely asymmetric case.

</DOC>
<DOC>
<DOCNO> 116877 </DOCNO>
Theory of nuclear spin conversion in ethylene


  First theoretical analysis of the nuclear spin conversion in ethylene
molecules (13^CCH4) has been performed. The conversion rate was found equal
approx. 3x10^{-4} 1/s*Torr, which is in qualitative agreement with the recently
obtained experimental value. It was shown that the ortho-para mixing in 13^CCH4
is dominated by the spin-rotation coupling. Mixing of only two pairs of
ortho-para levels were found to contribute significantly to the spin
conversion.

</DOC>
<DOC>
<DOCNO> 68492 </DOCNO>
Mesonic Anapole Form Factors of the Nucleons


  The chiral quark model posits pseudoscalar and vector meson couplings to
constituent quarks. The parity violating meson-quark couplings lead to anapole
moments and form factors of the nucleons. These arise both as parity violating
meson loop fluctuations as well as exchange currents and polarization currents
that are induced by the parity violating interaction between quarks. Because of
cancellations between the different contributions the magnitude of the
calculated anapole moments is only of the order $\sim 10^{-8}$ and is
determined mainly by magnitude of the parity-violating meson-nucleon coupling
constants.

</DOC>
<DOC>
<DOCNO> 101660 </DOCNO>
Abstract mechanical connection and Abelian reconstruction for almost


  When the phase space P of a Hamiltonian G-system (P, \omega, G, J, H) has an
almost Kahler structure a preferred connection, called abstract mechanical
connection, can be defined by declaring horizontal spaces at each point to be
metric orthogonal to the tangent to the group orbit. Explicit formulas for the
corresponding connection one-form A are derived in terms of the momentum map,
symplectic and complex structures. Such connection can play the role of the
reconstruction connection (see A. Blaom, Reconstruction phases via Poisson
reduction.
 Diff. Geom. Appl., 12:231--252, 2000.), thus significantly simplifying
computations of the corresponding dynamic and geometric phases for an Abelian
group G. These ideas are illustrated using the example of the resonant
three-wave interaction. Explicit formulas for the connection one-form and the
phases are given together with some new results on the symmetry reduction of
the Poisson structure.

</DOC>
<DOC>
<DOCNO> 150903 </DOCNO>
Holographic renormalization group flow, Wilson loops and field-theory


  We study the Renormalization Group (RG) flow of critical bosonic background
fields in the framework of the RG approach to string theory. In this approach
quantum field theory beta-functions are the extra inputs in solving the string
theory sigma-model equations. We study two different situations, the first one
is the Yang-Mills theory where the coupling constant diverges in the infrared
limit. The second case corresponds to a type of theories where the
beta-function has a pole in the infrared limit and it changes sign through the
pole (as in N=1 super-Yang-Mills theory). For this case in the strong coupling
branch, in the infrared, there is an interval of values of the coupling in
which the theory only leads to confinement. We have obtained this range. We
also mention the theories with conformal-fixed points and their relation to
theories with a pole in the beta-functions. We calculate the Wilson loops in
these theories.

</DOC>
<DOC>
<DOCNO> 118863 </DOCNO>
Large-Scale Regular Morphological Patterns in the Radio Jet of NGC 6251


  We report on large-scale, regular morphological patterns found in the radio
jet of the nearby radio galaxy NGC 6251. Investigating morphological properties
of this radio jet from the nucleus to a radial distance of $\sim$ 300 arcsec
($\approx$ 140 kpc) mapped at 1662 MHz and 4885 MHz by Perley, Bridle, &
Willis, we find three chains, each of which consists of five radio knots. We
also find that eight radio knots in the first two chains consist of three small
sub-knots (the triple-knotty substructures). We discuss the observational
properties of these regular morphological patterns.

</DOC>
<DOC>
<DOCNO> 117476 </DOCNO>
ISO SWS-LWS observations of the prototypical reflection nebula NGC 7023


  We present SWS and LWS ISO observations towards a strip across the
photodissociation region (PDR) in the reflection nebula NGC 7023. SWS02 and
LWS01 spectra have been taken towards the star and the brightest infrared
filaments located NW and SW from the star (hereafter NW and SW PDRs). In
addition, SWS02 spectra have been taken towards two intermediate positions.
  While all the PDR tracers (the [CII] 157.7$\mic$, [OI] 63.2 and 145.6$\mic$,
[HI] 21cm and the H$_2$ rotational lines) present a ring-like morphology with
the peaks toward the NW and SW PDRs and a minimum around the star, the SiII
emission is filling the hole of this ring with the peak towards the star. This
morphology can only be explained if the SiII emission arise in the lowest
extinction layers of the PDR (A$_v$ $<$ 2 mag) and the HII region. At least 20%
-- 30% of the Si must be in gas phase in these layers. For A$_v$ $\geq$ 2 mag,
the Si is mainly in solid form ($\delta$ Si = -1.3).
  In both, the NW and SW PDRs, the intensities of the H$_2$ rotational lines
can only be fitted by assuming an ortho-to-para-H$_2$ ratio lower than 3 in gas
with rotation temperatures from 400 to 700 K. Therefore, there is a
non-equilibrium OTP ratio in the region. The comparison between the OTP ratio
derived from H$_2$ vibrational lines and the pure H$_2$ rotational lines, shows
that the OTP ratio increases from $\sim$ 1.5 to 3 across the photodissociation
region with larger values in the less shielded gas (A$_v$$<$ 0.7 mag). This
behavior is interpreted as a consequence of an advancing photodissociation
front.

</DOC>
<DOC>
<DOCNO> 116618 </DOCNO>
Is the Time a Dimension of an Alien Universe? (this hypothesis gives an


  On the base of the hypothesis about a nature of the time as a dimension of
alien Universe relation between alteration of time with coordinates
$\frac{\partial t}{\partial x}$ and time {t} offered: $ \frac{\partial t}
{\partial x} = H_{t} t$ . This relation is an analogy of the Habble law in the
time space. The consequence of it is additional redshift $Z_{DT}$ depending on
differences $\tau$ of times existence of the objects with redshift that are
compared ($t_{0}$ is the time existence of more old object):
$Z_{DT}=\frac{1+\frac{\tau}{t_{0}}}{\sqrt{1-(\frac{\tau}{t_{0}}})^{2}}-1$. The
redshift of Arp galaxies may be explained if this relation is used and this
explanation doe's not contradict Arp hypothesis about supernova explosions.
Discussion a possibilities of experimental verification of the hypothesis is
considered.

</DOC>
<DOC>
<DOCNO> 101985 </DOCNO>
Funny Problems!


  Thirty original and collected problems, puzzles, and paradoxes in mathematics
and physics are explained in this paper, taught by the author to the elementary
and high school teachers at the University of New Mexico - Gallup in 1997-8 and
afterwards. They have more an educational interest, because make the students
think different! For each "solution" a funny logic is invented in order to give
the problem a sense.

</DOC>
<DOC>
<DOCNO> 170441 </DOCNO>
Quantum cloning optimal for joint measurements


  We show that universally covariant cloning is not optimal for achieving joint
measurements of noncommuting observables with minimum added noise. For such a
purpose a cloning transformation that is covariant with respect to a restricted
transformation group is needed.

</DOC>
<DOC>
<DOCNO> 122195 </DOCNO>
The Orion Star-Forming Region


  General properties of the Orion star-forming region are discussed, with a
focus on the dense Orion Nebula Cluster (ONC). This cluster contains between
2500 and 4500 objects located within a few parsecs of the eponymous Trapezium
stars. Its members are aged <1 to a few Myr and encompass the full spectrum of
stellar masses <50 Msun, as well as brown dwarfs detected with masses as low as
<0.02 Msun (20 Mjup) thusfar. Recent results from optical, near-infrared, and
x-ray studies of the stellar/sub-stellar population associated with this
cluster are summarized.

</DOC>
<DOC>
<DOCNO> 118970 </DOCNO>
Search for radio recombination lines towards the gravitational lens PKS


  A search for radio recombination lines near 20 cm at z=0.193 and z=0.886
towards the gravitational lens system PKS 1830-211 has yielded upper limits on
the line optical depth of 5 x 10^{-5} and 5 x10^{-4} at the two redshifts
respectively. Based on the non-detections, we derive upper limits to the
emission measure of the ionized gas in the absorbing systems. We also present
continuum flux density measurements over the frequency range 0.3-45 GHz made at
a single epoch.

</DOC>
<DOC>
<DOCNO> 102376 </DOCNO>
A nice bijection for a content formula for skew semistandard Young


  Based on Sch\"utzenberger's evacuation and a modification of jeu de taquin,
we give a bijective proof of an identity connecting the generating function of
reverse semistandard Young tableaux with bounded entries with the generating
function of all semistandard Young tableaux. This solves Exercise 7.102 b of
Richard Stanley's book `Enumerative Combinatorics 2'.

</DOC>
<DOC>
<DOCNO> 70472 </DOCNO>
QCD Glueball Regge Trajectories and the Pomeron


  We report a glueball Regge trajectory emerging from diagonalizing a confining
Coulomb gauge Hamiltonian for constituent gluons. Using a BCS vacuum ansatz and
gap equation, the dressed gluons acquire a mass, of order 800 $MeV$, providing
the quasiparticle degrees of freedom for a TDA glueball formulation. The TDA
eigenstates for two constituent gluons have orbital, $L$, excitations with a
characteristic energy of 400 $MeV$ revealing a clear Regge trajectory for
$\vec{J} = \vec{L} + \vec{S}$, where $S$ is the total (sum) gluon spin.
Significantly, the $S = 2$ glueball spectrum coincides with the Pomeron given
by $\alpha_P(t)=1.08+0.25 t $. Finally, we also ascertain that lattice data
supports our result, yielding an average intercept of 1.1 in good agreement
with the Pomeron.

</DOC>
<DOC>
<DOCNO> 123153 </DOCNO>
Spiral waves in accretion discs - observations


  I review the observational evidence for spiral structure in the accretion
discs of cataclysmic variables (CVs). Doppler tomography is ideally suited to
resolve and map such co-rotating patterns and allows a straightforward
comparison with theory. The dwarf nova IP Pegasi presents the best studied
case, carrying two spiral arms in a wide range of emission lines throughout its
outbursts. Both arms appear at the locations where tidally driven spiral waves
are expected, with the arm closest to the gas stream weaker in the lines
compared to the arm closest to the companion. Eclipse data indicates
sub-Keplerian velocities in the outer disc. The dramatic disc structure changes
in dwarf novae on timescales of days to weeks, provide unique opportunities for
our understanding of angular momentum transport and the role of density waves
on the structure of accretion discs.
  I present an extension to the Doppler tomography technique that relaxes one
of the basic assumptions of tomography, and is able to map modulated emission
sources. This extension allows us to fit anisotropic emission from, for
example, spiral shocks, the irradiated companion star and disc-stream
interaction sites.

</DOC>
<DOC>
<DOCNO> 117535 </DOCNO>
Comparison of Star Formation Rate estimations from $H_{\alpha}$, FIR and


  We used three indicators of massive star formation: $H_{\alpha}$, FIR and
non-thermal radio luminosities, to compare estimations of Star Formation Rate
(SFR) for the sample of 34 spiral galaxies. To adjust SFR values, obtained from
different indicators, we considered the slope $\alpha$ and/or upper mass limit
$M_{up}$ of Initial Mass Function (IMF) as free parameters. The best agreement
between these indicators reaches for $M_{up} \approx 60 - 100 ~M_{\odot}$ and
$\alpha \approx -3.1 $ in the high mass end of IMF ($M > 10 ~M_{\odot}$).
Parallel with SFR we also estimated FIR excess $X_{FIR}$ defined as a fraction
of the observed FIR which is not related to young massive stars directly.
$X_{FIR}$ is found to be well correlated with types of spiral galaxies and
their colors (B-V): the redder a galaxy the higher is its FIR excess. We
conclude that for any parameters of IMF the observed FIR flux of early type
spiral galaxies needs the additional source of energy but the massive star
radiation.

</DOC>
<DOC>
<DOCNO> 150913 </DOCNO>
Consistent Sphere Reductions and Universality of the Coulomb Branch in


  We prove that any D-dimensional theory comprising gravity, an antisymmetric
n-index field strength and a dilaton can be consistently reduced on S^n in a
truncation in which just $n$ scalar fields and the metric are retained in
(D-n)-dimensions, provided only that the strength of the couping of the dilaton
to the field strength is appropriately chosen. A consistent reduction can then
be performed for n\le 5; with D being arbitrary when n\le 3, whilst D\le 11 for
n=4 and D\le 10 for n=5. (Or, by Hodge dualisation, $n$ can be replaced by
(D-n) in these conditions.) We obtain the lower dimensional scalar potentials
and construct associated domain wall solutions. We use the consistent reduction
Ansatz to lift domain-wall solutions in the (D-n)-dimensional theory back to D
dimensions, where we show that they become certain continuous distributions of
(D-n-2)-branes. We also examine the spectrum for a minimally-coupled scalar
field in the domain-wall background, showing that it has a universal structure
characterised completely by the dimension n of the compactifying sphere.

</DOC>
<DOC>
<DOCNO> 71787 </DOCNO>
Unweighted event generation in hadronic WZ production at order(alpha_S)


  We present an algorithm for unweighted event generation in the partonic
process pp -> WZ (j) with leptonic decays at next-to-leading order in alpha_S.
Monte Carlo programs for processes such as this frequently generate events with
negative weights in certain regions of phase space. For simulations of
experimental data one would like to have unweighted events only. We demonstrate
how the phase space from the matrix elements can be combined to achieve
unweighted event generation using a second stage Monte Carlo integration over a
volume of real emissions (jets). Observable quantities are kept fixed in the
laboratory frame throughout the integration. The algorithm is applicable to a
broader class of processes and is CPU intensive.

</DOC>
<DOC>
<DOCNO> 12376 </DOCNO>
Open su(4)-invariant spin ladder with boundary defects


  The integrable su(4)-invariant spin-ladder model with boundary defect is
studied using the Bethe ansatz method. The exact phase diagram for the ground
state is given and the boundary quantum critical behavior is discussed. It
consists of a gapped phase in which the rungs of the ladder form singlet states
and a gapless Luttinger liquid phase. It is found that in the gapped phase the
boundary bound state corresponds to an unscreened local moment, while in the
Luttinger liquid phase the local moment is screened at low temperatures in
analogy to the Kondo effect.

</DOC>
<DOC>
<DOCNO> 152642 </DOCNO>
Solitons on compact and noncompact spaces in large noncommutativity


  We study solutions at the minima of scalar field potentials for Moyal spaces
and torii in the large non-commutativity and interprete these solitons in terms
of non-BPS D-branes of string theory. We derive a mass spectrum formula linking
different D-branes together on quantum torii and suggest that it describes
general systems of D-brane bound states extending the D2-D0 one. Then we
propose a shape for the effective potential approaching these quasi-stable
bound states. We give the gauge symmetries of these systems of branes and show
that they depend on the quantum torii representations.

</DOC>
<DOC>
<DOCNO> 121083 </DOCNO>
A comparison between Pa alpha and H alpha emission: The relation between


  We measure reddenings to HII regions in NGC 2903, NGC 1512, M51, NGC 4449 and
NGC 6946 from Hubble Space Telescope Pa alpha and H alpha images. Extinctions
range from A_V ~ 5 - 0 depending upon the galaxy. For the galaxies with HST
images in both lines, NGC 2903, NGC 1512 and M51, the Pa alpha and H alpha
emission are almost identical in morphology which implies that little emission
from bright HII regions is hidden from view by regions of comparatively high
extinction. The scatter in the measured extinctions is only +- 0.5 mag.
  We compare the reddenings we measure in five galaxies using the Pa alpha to H
alpha ratios to those measured previously from the Balmer decrement in the LMC
and as a function of radius in M101 and M51. We find that luminosity weighted
mean extinctions of these ensembles of HI regions are correlated with gas
surface density and metallicity. The correlation is consistent with the mean
extinction depending on dust density where the dust to gas mass ratio scales
with the metallicity. This trend is expected if HII regions tend to be located
near the mid-plane of a gas disk and emerge from their parent molecular clouds
soon after birth. In environments with gas densities below a few hundred
Msol/pc^2 star formation rates estimated from integrated line fluxes and mean
extinctions are likely to be fairly accurate.

</DOC>
<DOC>
<DOCNO> 122864 </DOCNO>
Why Are There Dwarf Spheroidal Galaxies?


  There appears to exist a conflict between the standard structure formation
theory and the existence of the faint dwarf spheroidal galaxies in the Local
Group. Theoretical considerations suggest that a cold dark matter universe has
been a very hostile place for the formation of small galaxies. In particular,
gas would not have been able to cool and condense to form stars inside dark
matter halos with a velocity dispersion <10km/s since before the cosmological
reionization epoch. In other words, one should not expect to see any major star
formation activities in dwarf galaxies with a velocity dispersion <10km/s
during the past 12Gyr, according to the current structure formation theory. The
real universe, on the other hand, shows that all dwarf spheroidal galaxies in
the Local Group have velocity dispersions <10km/s and extended and recent star
formation activities are quite common in them. This apparent conflict between
cold dark matter models and local observations can be resolved, if one allows
the cold dark matter particles to decay relatively recently. The resolution
comes about in that the dwarf spheroidal galaxies with a velocity dispersion of
\~10km/s seen today were born, in this picture, in a small fraction of halos
with a velocity dispersion of ~20km/s, where gas can be retained and is able to
cool and contract to form stars. The presently observed lower velocity
dispersion ~10km/s of these dwarf spheroidal galaxies is a consequence of the
decay of one half of the dark matter in and subsequent expansion of the halos
since redshift z~2.

</DOC>
<DOC>
<DOCNO> 13394 </DOCNO>
Origin of Spin Incommensurability in Hole-doped S=1 $\rm Y_{2-x}Ca_x Ba


  Spin incommensurability has been recently experimentally discovered in the
hole-doped Ni-oxide chain compound $\rm Y_{2-x}Ca_x Ba Ni O_5$ (G. Xu {\it
al.}, Science {\bf 289}, 419 (2000)). Here a two orbital model for this
material is studied using computational techniques. Spin IC is observed in a
wide range of densities and couplings. The phenomenon originates in
antiferromagnetic correlations ``across holes'' dynamically generated to
improve hole movement, as it occurs in the one-dimensional Hubbard model and in
recent studies of the two-dimensional extended t-J model. The close proximity
of ferromagnetic and phase-separated states in parameter space are also
discussed.

</DOC>
<DOC>
<DOCNO> 84087 </DOCNO>
Finite Temperature Field Theory of "Extreme Black Holes"


  We treat the model which describes "extreme black holes" moving slowly. We
derive an effective lagrangian in the low energy for this model and then
investigate a statistical behavior of "extreme black holes" in the finite
temperature.

</DOC>
<DOC>
<DOCNO> 13140 </DOCNO>
Dichromatic polynomials and Potts models summed over rooted maps


  We consider the sum of dichromatic polynomials over non-separable rooted
planar maps, an interesting special case of which is the enumeration of such
maps. We present some known results and derive new ones. The general problem is
equivalent to the $q$-state Potts model randomized over such maps. Like the
regular ferromagnetic lattice models, it has a first-order transition when $q$
is greater than a critical value $q_c$, but $q_c$ is much larger - about 72
instead of 4.

</DOC>
<DOC>
<DOCNO> 85397 </DOCNO>
Conformal derivative and conformal transports over spaces with


  Transports preserving the angle between two contravariant vector fields but
changing their lengths proportional to their own lengths are introduced as
''conformal'' transports and investigated over spaces with contravariant and
covariant affine connections (whose components differ not only by sign) and
metrics. They are more general than the Fermi-Walker transports. In an
analogous way as in the case of Fermi-Walker transports a conformal covariant
differential operator and its conformal derivative are defined and considered
over the above mentioned spaces. Different special types of conformal
transports are determined inducing also Fermi-Walker transports for orthogonal
vector fields as special cases. Conditions under which the length of a non-null
contravariant vector field could swing as a homogeneous harmonic oscillator are
established. The results obtained regardless of any concrete field
(gravitational) theory could have direct applications in such types of
theories.
  PACS numbers: 04.90.+e; 04.50.+h; 12.10.Gq; 02.40.Vh

</DOC>
<DOC>
<DOCNO> 123103 </DOCNO>
Type Ia Supernovae: Toward the Standard Model?


  In this short review I suggest that recent developments support the
conjecture that Type Ia supernovae (SNe Ia) are the complete disruptions of
Chandrasekhar-mass carbon-oxygen white dwarfs in single-degenerate binary
systems. The causes of the observational diversity of SNe Ia within the context
of this standard model, and the implications of the model for young remnants of
SNe Ia, are briefly discussed.

</DOC>
<DOC>
<DOCNO> 120112 </DOCNO>
Extensive molecular gas in the tidal arms near NGC3077 - Birth of a


  Using the IRAM 30m radio telescope we have mapped the tidal arm feature
south-east of NGC3077 where we recently detected molecular gas in the CO
(J=1-0) and (2-1) transitions. We find that the molecular gas is much more
extended than previously thought (several kpc). The CO emission can be
separated into at least 3 distinct complexes with equivalent radii between
250pc and 700pc and all well confined over a narrow range in velocity. For one
complex we have also obtained a CO (3-2) spectrum using the KOSMA 3m radio
telescope; utilizing an LVG model we find that the kinetic temperature for this
complex must be about 10K, and the H2 volume density between 600 and
10000cm^-3. Mass estimates based on virialization yield a total mass for the
complexes of order 2-4 10^7 M_sun, i.e. more than the estimated molecular mass
within NGC3077 itself. This implies that interactions between galaxies can
efficiently remove heavy elements and molecules from a galaxy and enrich the
intergalactic medium. A comparison of the distribution of HI and CO shows no
clear correlation. However, CO is only found in regions where the HI column
density exceeds 1.1 10^21 cm^-2. HI masses for the molecular complexes mapped
are of the same order as the corresponding molecular masses. Since the tidal
arm with its molecular complexes has all the ingredients to form stars in the
future, we are thus presumably witnessing the birth of a dwarf galaxy. This
process could be important for the formation of dwarf galaxies especially at
larger look-back times in the universe where galaxy interactions may have been
more frequent.

</DOC>
<DOC>
<DOCNO> 117474 </DOCNO>
Resolving the jeans mass in hydrodynamic simulations of hierarchical


  We examine the necessity of resolving the Jeans mass in hydrodynamical
simulations of the hierarchical formation of cosmological structures. We
consider a standard two-component fluid and use smoothed particle hydrodynamics
to model the baryonic component. It is found that resolution of the Jeans mass
is not necessary to extract bulk properties of bound objects that are
independent of resolution, provided that the objects have undergone a number of
merger events. The degree of merging must be sufficient to populate the objects
with substructure of similar total mass. After this criterion is met, neither
the density profiles of structures nor their density-temperature distributions
depend appreciably on the resolution of the simulation. Resolution of the Jeans
mass by the imposition of a minimum temperature is not found to adversely
affect the state of the matter in the final clusters. The baryon concentration
profiles still indicate a deficit of gas with respect to the dark matter in the
interiors of structures.

</DOC>
<DOC>
<DOCNO> 69116 </DOCNO>
New Mechanism for Mass Generation of Gauge Fields


  A new mechanism for mass generation of gauge fields is proposed in this
paper. By introducing two sets of gauge fields and making the variatons of
these two sets of gauge fields compensate each other under local gauge
transformations, the mass term of gauge fields can be introduced into the
Lagrangian without violation the local gauge symmetry of the Lagrangian.
Besides, this model is renormalizable.

</DOC>
<DOC>
<DOCNO> 118023 </DOCNO>
Event categories in the EDELWEISS WIMP search experiment


  Four categories of events have been identified in the EDELWEISS-I dark matter
experiment using germanium cryogenic detectors measuring simultaneously charge
and heat signals. These categories of events are interpreted as electron and
nuclear interactions occurring in the volume of the detector, and electron and
nuclear interactions occurring close to the surface of the detectors(10-20 mu-m
of the surface). We discuss the hypothesis that low energy surface nuclear
recoils,which seem to have been unnoticed by previous WIMP searches, may
provide an interpretation of the anomalous events recorded by the UKDMC and
Saclay NaI experiments. The present analysis points to the necessity of taking
into account surface nuclear and electron recoil interactions for a reliable
estimate of background rejection factors.

</DOC>
<DOC>
<DOCNO> 68024 </DOCNO>
The dynamics of curved gravitating walls


  We examine the dynamics of a self-gravitating domain wall using the $\lambda
\Phi^4$ model as a specific example. We find that the Nambu motion of the wall
is quite generic and dominates the wall motion even in the presence of gravity.
We calculate the corrections to this leading order motion, and estimate the
effect of the inclusion of gravity on the dynamics of the wall. We then treat
the case of a spherical gravitating thick wall as a particular example, solving
the field equations and calculating the corrections to the Nambu motion
analytically for this specific case. We find that the presence of gravity
retards collapse in this case.

</DOC>
<DOC>
<DOCNO> 117637 </DOCNO>
Gravitational Lensing of High Redshift Sources


  The combination of deep exposures and high resolution offered by telescopes
in space allows the detection of lensing over a wide range of source redshifts
and lens masses. As an example, we model a lens candidate found in the southern
Hubble Deep Field. The system consists of a source galaxy lensed into an arc,
0.9 arcseconds from an elliptical galaxy with an implied mass-to-light ratio of
order 15 in solar units. This lens system may be a preview of the large number
of lensed high-redshift galaxies that will be detected with the Next Generation
Space Telescope (NGST). Popular models of structure formation imply that
roughly 3% of observed sources at z>5 should be multiply imaged. Thus, NGST
should detect several lensed objects in each field of view. In addition, NGST
will be a valuable tool for weak lensing measurements if it can resolve the
background galaxies. We estimate the angular size distribution of high redshift
sources within hierarchical models of structure formation and find that most
will be resolved. (abridged)

</DOC>
<DOC>
<DOCNO> 101437 </DOCNO>
Classical Yang-Baxter equation and the $A_{\infty}$-constraint


  We show that elliptic solutions of the classical Yang-Baxter equation can be
obtained from triple Massey products on elliptic curve. We introduce the
associative version of this equation which has two spectral parameters and
construct its elliptic solutions. We also study some degenerations of these
solutions.

</DOC>
<DOC>
<DOCNO> 102442 </DOCNO>
Toric integrable geodesic flows


  By studying completely integrable torus actions on contact manifolds we prove
a conjecture of Toth and Zelditch that toric integrable geodesic flows on tori
must have flat metrics.

</DOC>
<DOC>
<DOCNO> 12920 </DOCNO>
Model calculations of the proximity effect in finite multilayers


  The proximity-effect theory developed by Takahashi and Tachiki for infinite
multilayers is applied to multilayer systems with a finite number of layers in
the growth direction. The purpose is to investigate why previous applications
to infinite multilayers fail to describe the measured data satisfactorily.
Surface superconductivity may appear, depending on the thickness of the
covering normal metallic N layers on both the top and the bottom. The
parameters used are characteristic for V/Ag and Nb/Pd systems. The nucleation
process is studied as a function of the system parameters.

</DOC>
<DOC>
<DOCNO> 119607 </DOCNO>
First Structure Formation and the First Stars


  We discuss the results of recent 3D simulations of first structure formation
in relationship to the formation of the first stars. On the basis of a new,
high-resolution AMR simulation (spatial dynamic range = 30,000,000), we
conclude that the first stars are likely to be massive.

</DOC>
<DOC>
<DOCNO> 117804 </DOCNO>
Quasar Jets and their Fields


  Observations of jets from quasars and other types of accreting black hole are
briefly summarized. The importance of beaming and $\gamma$-ray observations for
understanding the origin of these jets is emphasised. It is argued that both
the power source and the collimation are likely to be magnetic in origin,
although the details remain controversial. Ultrarelativistic jets may be formed
by the spinning hole and collimated by a hydromagnetic disc wind. Progress in
understanding jets has been handicapped by our inadequate knowledge of how
magnetic field really behaves under cosmic conditions. Fortunately, significant
insights are coming from solar observations, numerical simulation and
laboratory plasma experiments. Some possible, evolutionary ramifications are
briefly discussed and it is suggested that it is the mass of the black hole
relative to that of the galaxy which determines the eventual galaxy morphology.

</DOC>
<DOC>
<DOCNO> 170721 </DOCNO>
Exact solutions for classical few-body systems from the multichannel


  A surprising "duality" of the Newton equation with time-dependent forces and
the stationary Schroedinger equation is discussed. Wide classes of exact
solutions not known before for few-body Newton equations are generated directly
from exactly solvable multichannel models discovered in quantum mechanics due
to the inverse problem and the supersymmetry (SUSYQ) approach. The application
of this duality to the control of the stability (bifurcations) of classical
motions is suggested.

</DOC>
<DOC>
<DOCNO> 71350 </DOCNO>
MUM: flexible precise Monte Carlo algorithm for muon propagation through


  We present a new Monte Carlo muon propagation algorithm MUM (MUons+Medium)
which possesses some advantages over analogous algorithms presently in use. The
most important features of algorithm are described. Results on the test for
accuracy of treatment the muon energy loss with MUM are presented and analyzed.
It is evaluated to be of 0.002 or better, depending upon simulation parameters.
Contributions of different simplifications which are applied at Monte Carlo
muon transportation to the resulting error are considered and ranked. It is
shown that when simulating muon propagation through medium it is quite enough
to account only for fluctuations in radiative energy loss with fraction of
energy lost being as large as 0.05 -- 0.1. Selected results obtained with MUM
are given and compared with ones from other algorithms.

</DOC>
<DOC>
<DOCNO> 10657 </DOCNO>
NMR relaxation rate of (quasi-)one-dimensional spin gapped systems in


  The NMR relaxation rates of (quasi-)one-dimensional spin gapped systems such
as the $S=1/2$ spin ladder with a diagonal interaction and the Haldane-gap
system are investigated at low temperatures in magnetic fields. We show that in
the regime where the gap is collapsed by magnetic fields, the NMR relaxation
rate diverges with decreasing temperature and its exponent shows a behavior
characteristic of the model as a function of magnetic field. We discuss our
results in comparison with recent experimental findings for the spin ladder
system ${\rm Cu_{2}(C_{5}H_{12}N_{2})_{2}Cl_{4}}$ and for the Haldane-gap
system ${\rm (CH_3)_4NNi(NO_2)_3}$.

</DOC>
<DOC>
<DOCNO> 122332 </DOCNO>
Metal abundance of the eclipsing binary YZ Cas: discrepancy between


  We review current and new estimates of the eclipsing binary YZ Cassiopeiae
metallicity (Z). Since the individual components cover a quite large range of
mass (1.35-2.31 Solar masses), YZ Cas is potentially one of the best stellar
laboratories to understand the structure and evolution of 1 to 2 Solar masses
stars. The derivation of Z from IUE spectra, as well as from photometric
indices, provides the chemical composition of the atmosphere (Z_{atmospheric}),
while the fit of evolutionary tracks provides the initial chemical composition
(Z_{initial}). While a disagreement is expected between Z_{atmospheric} and
Z_{initial} because the primary component is an Am star (one expects
Z_{atmospheric} to be larger), we find some unexpected discrepancy between
atmospheric determinations of Z for this star.

</DOC>
<DOC>
<DOCNO> 84988 </DOCNO>
Topological Black Holes in Quantum Gravity


  We derive the black hole solutions with horizons of non-trivial topology and
investigate their properties in the framework of an approach to quantum gravity
being an extension of Bohm's formulation of quantum mechanics. The solutions we
found tend asymptotically (for large $r$) to topological black holes. We also
analyze the thermodynamics of these space-times.

</DOC>
<DOC>
<DOCNO> 68314 </DOCNO>
A Note on Anomaly Matching for Finite Density QCD


  We note that the QCD phases at large finite density respect 't Hooft anomaly
matching conditions. Specifically the spectrum of the light excitations
possesses the correct quantum numbers required to obey global anomaly
constraints. We argue that 't Hooft constraints can be used at finite density
along with non perturbative methods to help selecting the correct phase.

</DOC>
<DOC>
<DOCNO> 122942 </DOCNO>
Potential Sources of Gravitational Wave Emission and Laser Beam


  The properties of potential gravitational wave sources like neutron stars,
black holes and binary systems are reviewed, as well as the different
contributions (stochastic and continuous) to the gravitational wave background.
The detectability of these sources by the present generation of laser beam
interferometers, which will be fully operational around 2002, is also
considered.

</DOC>
<DOC>
<DOCNO> 85145 </DOCNO>
Imprints of accretion on gravitational waves from black holes


  Black holes are superb sources of gravitational wave signals, for example
when they are born in stellar collapse. We explore the subtleties that may
emerge if mass accretion events increase significantly the mass of the black
hole during its gravitational wave emission. We find the familiar
damped-oscillatory radiative decay but now both decay rate and frequencies are
modulated by the mass accretion rate. Any appreciable increase in the horizon
mass during emission reflects on the instantaneous signal frequency, which
shows a prominent negative branch in the dot[f](f) evolution diagram. The
features of the frequency evolution pattern reveal key properties of the
accretion event, such as the total accreted mass and the accretion rate. For
slow accretion rates the frequency evolution follows verbatim the accretion
rate, as expected from dimensional arguments. In view of the possibility of
detection of black hole ``ringing'' by the upcoming gravitational wave
experiments, the deciphering of the late time frequency dynamics may provide
direct insight into otherwise obscured aspects of the black hole birth process.

</DOC>
<DOC>
<DOCNO> 9716 </DOCNO>
A universality class in Markovian persistence


  We consider the class of Markovian processes defined by the equation $\dd x
/\dd t = -\beta x + \sum_k z_k \delta (t-t_k)$. Such processes are encountered
in systems (like coalescing systems) where dynamics creates discrete upward
jumps at random instants $t_k$ and of random height $z_k$. We observe that the
probability for these processes to remain above their mean value during an
interval of time $T$ decays as $\exp{-\theta T}$ defining $\theta$ as the
persistence exponent. We show that $\theta$ takes the value $\beta$ which
thereby extends the well known result of the Gaussian noise case to a much
larger class of non-Gaussian processes.

</DOC>
<DOC>
<DOCNO> 70260 </DOCNO>
Implications of a Small CP Asymmetry in B->\psi K_S


  New measurements of the CP asymmetry in B->\psi K_S, a_{\psi K_S}, by the
BABAR and BELLE collaborations are consistent with the Standard Model
prediction for sin2\beta. These measurements, however, leave open the
possibility that a_{\psi K_S} is well below the Standard Model prediction. We
identify deviations from the `reasonable ranges' of hadronic parameters that
can lead to low values of sin2\beta. New physics, mainly in B^0-\barB^0 mixing
and/or K^0-\barK^0 mixing, can explain low values of a_{\psi K_S} in two ways:
either by allowing for values of sin2\beta below the Standard Model prediction
or by modifying the relation between a_{\psi K_S} and sin2\beta.

</DOC>
<DOC>
<DOCNO> 100229 </DOCNO>
Remarks about uniform boundedness of rational points over function


  We prove a few uniform versions of the Mordell-Lang Conjecture and of the
Shafarevich Conjecture for curves over function fields and their rational
points. The main focus is on function fields having high transcendence degree
over the complex numbers.

</DOC>
<DOC>
<DOCNO> 71529 </DOCNO>
Electroweak Physics for Color Superconductivity


  We construct the effective theories describing the electroweak interactions
for the low energy excitations associated with the color superconductive phases
of QCD at high matter density. The main result, for the 3 flavor case, is that
the quasiparticle Goldstone boson $\pi^0$ decay into two physical massless
photons is identical to the zero density case once we use the new Goldstone
decay constant and the modified electric charge $\widetilde{e}=e \cos\theta$,
with $\tan\theta =2e/\sqrt{3}g_s$ and $g_s$ the strong coupling constant. For 2
flavors we find that the coupling of the quarks to the neutral vector boson
$Z^0$ is modified with respect to the zero density case. We finally point out
possible applications of our result to the physics of compact objects.

</DOC>
<DOC>
<DOCNO> 170338 </DOCNO>
Detection statistics in the micromaser


  We present a general method for the derivation of various statistical
quantities describing the detection of a beam of atoms emerging from a
micromaser. The user of non-normalized conditioned density operators and a
linear master equation for the dynamics between detection events is discussed
as are the counting statistics, sequence statistics, and waiting time
statistics. In particular, we derive expressions for the mean number of
successive detections of atoms in one of any two orthogonal states of the
two-level atom. We also derive expressions for the mean waiting times between
detections. We show that the mean waiting times between de- tections of atoms
in like states are equivalent to the mean waiting times calculated from the
uncorrelated steady state detection rates, though like atoms are indeed
correlated. The mean waiting times between detections of atoms in unlike states
exhibit correlations. We evaluate the expressions for various detector
efficiencies using numerical integration, reporting re- sults for the standard
micromaser arrangement in which the cavity is pumped by excited atoms and the
excitation levels of the emerging atoms are measured. In addition, the atomic
inversion and the Fano-Mandel function for the detection of de-excited atoms is
calculated for compari- son to the recent experimental results of Weidinger
et al. [1], which reports the first observation of trapping states.

</DOC>
<DOC>
<DOCNO> 10357 </DOCNO>
Atomic scale engines: Cars and wheels


  We introduce a new approach to build microscopic engines on the atomic scale
that move translationally or rotationally and can perform useful functions such
as pulling of a cargo. Characteristic of these engines is the possibility to
determine dynamically the directionality of the motion. The approach is based
on the transformation of the fed energy to directed motion through a dynamical
competition between the intrinsic lengths of the moving object and the
supporting carrier.

</DOC>
<DOC>
<DOCNO> 122568 </DOCNO>
NGC 6251 at multiple scales and wavelengths


  We have studied the FR I radio galaxy NGC 6251 and its environment at several
wavelengths and scale lengths. On the large scale, we have probed the gravity
field by measuring the velocity dispersion of the cluster members associated
with NGC 6251 and relating this to the cluster's X-ray emission. On the small
scale, the gravitational information is provided by cold HI near the nucleus
and the distribution of stars and gas near the centre of the galaxy. The cold
HI gas which we have measured explains the absorption of the central X-ray
emission and is consistent with the extinction through the recently discovered
HST gas disc of NGC 6251.

</DOC>
<DOC>
<DOCNO> 11307 </DOCNO>
ab initio modeling of open systems: charge transfer, electron


  We present an {\it ab initio} analysis of electron conduction through a
$C_{60}$ molecular device. Charge transfer from the device electrodes to the
molecular region is found to play a crucial role in aligning the lowest
unoccupied molecular orbital (LUMO) of the $C_{60}$ to the Fermi level of the
electrodes. This alignment induces a substantial device conductance of $\sim
2.2 \times (2e^2/h)$. A gate potential can inhibit charge transfer and
introduce a conductance gap near $E_F$, changing the current-voltage
characteristics from metallic to semi-conducting, thereby producing a field
effect molecular current switch.

</DOC>
<DOC>
<DOCNO> 170745 </DOCNO>
Telecloning and multiuser quantum channels for continuous variables


  We propose entangled (M+1)-mode quantum states as a multiuser quantum channel
for continuous-variable communication. Arbitrary quantum states can be sent via
this channel simultaneously to M remote and separated locations with equal
minimum excess noise in each output mode. For a set of coherent-state inputs,
the channel realizes optimum symmetric 1-to-M cloning at a distance
(``telecloning''). It also provides the optimal cloning of coherent states
without the need of amplifying the state of interest. The generation of the
multiuser quantum channel requires no more than two
10\log_{10}[(\sqrt{M}-1)/(\sqrt{M}+1)] dB squeezed states and M beam splitters.

</DOC>
<DOC>
<DOCNO> 10807 </DOCNO>
Fractionalization in the cuprates: Detecting the topological order


  The precise theoretical characterization of a fractionalized phase in spatial
dimensions higher than one is through the concept of ``topological order''. We
describe a physical effect that is a robust and direct consequence of this
hidden order that should enable a precise experimental characterization of
fractionalized phases. In particular, we propose specific ``smoking-gun''
experiments to unambiguously settle the issue of electron fractionalization in
the underdoped cuprates.

</DOC>
<DOC>
<DOCNO> 9419 </DOCNO>
Shear instabilities of freely standing thermotropic smectic-A films


  In this Letter we discuss theoretically the instabilities of thermotropic
freely standing smectic-A films under shear flow\cite{re:wu}. We show that, in
Couette geometry, the centrifugal force pushes the liquid crystal toward the
outer boundary and induces smectic layer dilation close to the outer boundary.
Under strong shear, this effect induces a layer buckling instability. The
critical shear rate is proportional to $1/\sqrt{d}$, where $d$ is the thickness
of the film.

</DOC>
<DOC>
<DOCNO> 12128 </DOCNO>
Exact diagonalization Studies of Two-dimensional Frustrated


  We describe the four kinds of behavior found in two-dimensional isotropic
quantum antiferromagnets. Two of them display long range order at T=0: the
N\'eel state and the Valence Bond Crystal. The last two are Spin-Liquids.
Properties of these different states are shortly described and open questions
are underlined.

</DOC>
<DOC>
<DOCNO> 8969 </DOCNO>
Properties of convergence of nonextensive statistical distribution to


  It is shown that the distribution derived from the principle of maximum
Tsallis entropy is a superposable Levy-type distribution. Concomitantly, the
leading order correction to the limit distribution is also deduced. This
demonstration fills an important gap in the derivation of the Levy-stable
distribution from the nonextensive statistical framework.

</DOC>
<DOC>
<DOCNO> 119828 </DOCNO>
No diffuse H2 in the metal deficient galaxy I Zw 18


  The metal deficient starburst galaxy IZw18 has been observed with FUSE in a
search for H2 molecules. The spectrum obtained with an aperture covering the
full galaxy shows no absorption lines of diffuse H2 at the radial velocity of
the galaxy. The upper limit for the diffuse H2 column density is found to be
very low: N(H2) <~ 10^15 cm-2 (10 sigma), unlike our Galaxy where H2 is
generally present for even low HI column densities. Although the HI column
density is here as high as N(HI) ~ 2.10^21 cm-2, we observe 2N(H2)/N(HI)<<
10^-6. We cannot exclude the possibility that some H2 could be in very dense,
small and discrete clumps which cannot be detected with the present
observation. However, the remarkable absence of diffuse H2 in this metal-poor
galaxy can be explained by the low abundance of dust grains (needed to form
this molecule from H-atoms), the high ultraviolet flux and the low density of
the HI cloud surrounding the star-forming regions. Thus having eliminated
diffuse H2 as a significant contributor to the total mass, it appears that the
gas of the galaxy is dominated by HI, and that the high dynamical mass is not
composed of cold and diffuse baryonic dark matter.

</DOC>
<DOC>
<DOCNO> 71355 </DOCNO>
Charmless hadronic decays $B \to PP, PV, VV$ and new physics effects in


  Based on the low-energy effective Hamiltonian with the generalized
factorization, we calculate the new physics contributions to the branching
ratios of the two-body charmless hadronic decays of $B_u$ and $B_d$ mesons
induced by the new gluonic and electroweak charged-Higgs penguin diagrams in
the general two-Higgs doublet models (models I, II and III). Within the
considered parameter space, we find that: (a) the new physics effects from new
gluonic penguin diagrams strongly dominate over those from the new $\gamma$-
and $Z^0$- penguin diagrams; (b) in models I and II, new physics contributions
to most studied B meson decay channels are rather small in size: from -15% to
20%; (c) in model III, however, the new physics enhancements to the
penguin-dominated decay modes can be significant, $\sim (30 -200)%$, and
therefore are measurable in forthcoming high precision B experiments; (d) the
new physics enhancements to ratios ${\cal B}(B \to K \etap)$ are significant in
model III, $\sim (35 -70)%$, and hence provide a simple and plausible new
physics interpretation for the observed unexpectedly large $B \to K \etap $
decay rates; (e) the theoretical predictions for ${\cal B}(B \to K^+ \pi)$ and
${\cal B}(B \to K^0 \pi^+)$ in model III are still consistent with the data
within $2\sigma$ errors; (f) the significant new physics enhancements to the
branching ratios of $B \to K^0 \pi^0, K^* \eta, K^{*+} \pi^-, K^+ \phi, K^{*0}
\omega, K^{*+} \phi$ and $K^{*0} \phi$ decays are helpful to improve the
agreement between the data and the theoretical predictions; (g) the theoretical
predictions of ${\cal B}(B \to PP, PV, VV)$ in the 2HDM's are generally
consistent with experimental measurements and upper limits ($90% C.L.$)

</DOC>
<DOC>
<DOCNO> 116853 </DOCNO>
The Mechanical Design for the Darht-II Downstream Beam Transport Line


  This paper describes the mechanical design of the downstream beam transport
line for the second axis of the Dual Axis Radiographic Hydrodynamic Test (DARHT
II) Facility. The DARHT-II project is a collaboration between LANL, LBNL and
LLNL. DARHT II is a 20-MeV, 2000-Amperes, 2-msec linear induction accelerator
designed to generate short bursts of x-rays for the purpose of radiographing
dense objects. The down-stream beam transport line is approximately 20-meter
long region extending from the end of the accelerator to the bremsstrahlung
target. Within this proposed transport line there are 15 conventional solenoid,
quadrupole and dipole magnets; as well as several speciality magnets, which
transport and focus the beam to the target and to the beam dumps. There are two
high power beam dumps, which are designed to absorb 80-kJ per pulse during
accelerator start-up and operation. Aspects of the mechanical design of these
elements are presented.

</DOC>
<DOC>
<DOCNO> 116788 </DOCNO>
Development of Rebunching Cavities at IAP


  A focus of work at IAP has been the development and optimization of spiral
loaded cavities since the 1970s [A. Schempp et al, NIM 135, 409 (1976)]. These
cavities feature a high efficiency, a compact design and a big variety of
possible fields of application. They find use both as bunchers and post
accelerators to vary the final energy of the beam. In comparison to other
available designs, the advantage of these structures lies in their small size.
Furthermore they can easily be tuned to the required resonance frequency by
varying the length of the spiral. Due to the small size of the cavities the
required budget can also be kept low. Here, two slightly different types of
spiral loaded cavities, which were built for the REX-ISOLDE project at CERN and
the intensity upgrade program at GSI are being discussed.

</DOC>
<DOC>
<DOCNO> 84640 </DOCNO>
Self-force on a scalar particle in spherically-symmetric spacetime via


  Recently, we proposed a method for calculating the ``radiation reaction''
self-force exerted on a charged particle moving in a strong field orbit in a
black hole spacetime. In this approach, one first calculates the contribution
to the ``tail'' part of the self force due to each multipole mode of the
particle's self field. A certain analytic procedure is then applied to
regularize the (otherwise divergent) sum over modes. This involves the
derivation of certain regularization parameters using local analysis of the
(retarded) Green's function. In the present paper we present a detailed
formulation of this mode-sum regularization scheme for a scalar charge on a
class of static spherically-symmetric backgrounds (including, e.g., the
Schwarzschild, Reissner-Nordstr\"{o}m, and Schwarzschild-de Sitter spacetimes).
We fully implement the regularization scheme for an arbitrary radial trajectory
(not necessarily geodesic) by explicitly calculating all necessary
regularization parameters in this case.

</DOC>
<DOC>
<DOCNO> 40382 </DOCNO>
High-order corrections and subleading logarithms for top quark


  We derive high-order threshold corrections for top quark production in
hadronic collisions from resummation calculations. We present analytical
expressions for the cross section through
next-to-next-to-next-to-next-to-leading order (N^4LO) and
next-to-next-to-leading logarithmic accuracy. Special attention is paid to the
role of subleading logarithms and how they relate to the convergence of the
perturbation series and differences between various resummation prescriptions.
It is shown that care must be taken to avoid unphysical terms in the
expansions. Numerical results are presented for top quark production at the
Tevatron. We find sizeable increases to the total cross section and
differential distributions and a dramatic reduction of the factorization scale
dependence relative to next-to-leading order.

</DOC>
<DOC>
<DOCNO> 122737 </DOCNO>
Three modes of long wavelength flaring from GRS 1915+105: implications


  GRS 1915+105 has exhibited at least three modes of long-wavelength (infrared
to radio) flares. Class A flares are the bright ($\sim 1$ Jy) radio events
whose apparent superluminal motion in many ways defines the microquasars. Class
B flares have intermediate ($\sim 50-300$ mJy) flux densities in the IR and
radio, and are associated with hard X-ray dipping behaviors. Class C flares are
faint ($\sim 5-50$ mJy) IR/radio events associated with soft X-ray dips. We
discuss each of these classes and their inter-relationships.

</DOC>
<DOC>
<DOCNO> 118492 </DOCNO>
Quark-Hadron Phase Transitions in Young and Old Neutron Stars


  The mixed phase of quarks and hadrons which might exist in the dense matter
encountered in the varying conditions of temperature and trapped neutrino
fraction in proto-neutron stars is studied. The extent that the mixed phase
depends upon the thermodynamical parameters as well as on the stiffness of
matter in the hadronic and quark phases is discussed. We show that hadronic
equations of state that maximize the quark content of matter at a given {\it
density} generally minimize the extent of the mixed phase region in a neutron
star of a given mass, and that only in extreme cases could a pure quark star
result. For both the Nambu Jona-Lasinio and MIT bag quark models, neutrino
trapping inhibits the appearance of a mixed phase which leads to possible
proto-neutron star metastability. The main difference between the two quark
models is the small abundance of strange quarks in the former. We also
demonstrate that $\partial T/\partial n<0$ along adiabats in the quark-hadron
mixed phase, opposite to what is found for the kaon condensates-hadron mixed
phase. This could lead to core temperatures which are significantly lower in
stars containing quarks than in those not containing quarks.

</DOC>
<DOC>
<DOCNO> 120496 </DOCNO>
Comment on "On physical interpretation of the Poynting-Robertson effect"


  In response to the comments of astro-ph/0006426 on Srikanth (Icarus 1999), we
clarify, and thereby justify, the definition of Poynting-Robertson drag adopted
in the latter. We confirm that dust absorption is a necessary condition while
re-emission is neither necessary nor sufficient for the inspiralling of a
rest-isotropically emitting dust.

</DOC>
<DOC>
<DOCNO> 117214 </DOCNO>
Classical analysis of correlated multiple ionization in strong fields


  We discuss the final stages of the simultaneous ionization of two or more
electrons due to a strong laser pulse. An analysis of the classical dynamics
suggests that the dominant pathway for non-sequential escape has the electrons
escaping in a symmetric arrangement. Classical trajectory models within and
near to this symmetry subspace support the theoretical considerations and give
final momentum distributions in close agreement with experiments.

</DOC>
<DOC>
<DOCNO> 12708 </DOCNO>
Deconfinement Transition and Bound States in Frustrated Heisenberg


  We use recently developed strong-coupling expansion methods to study the
two-particle spectra for the frustrated alternating Heisenberg model,
consisting of an alternating nearest neighbor antiferromagnetic exchange and a
uniform second neighbor antiferromagnetic exchange. Starting from the limit of
weakly coupled dimers, we develop high order series expansions for the
effective Hamiltonian in the two-particle subspace. In the limit of a strong
applied dimerization, we calculate accurately various properties of singlet and
triplet bound states and quintet antibound states. We also develop series
expansions for bound state energies in various sectors, which can be
extrapolated using standard methods to cases where the external
bond-alternation goes to zero. We study the properties of singlet and triplet
bound states in the latter limit and suggest a crucial role for the bound
states in the unbinding of triplets and deconfinement of spin-half excitations.

</DOC>
<DOC>
<DOCNO> 12161 </DOCNO>
Quantum Monte Carlo calculation of the finite temperature Mott-Hubbard


  We present clear numerical evidence for the coexistence of metallic and
insulating dynamical mean field theory(DMFT) solutions in a half-filled
single-band Hubbard model with bare semicircular density of states at finite
temperatures. Quantum Monte Carlo(QMC) method is used to solve the DMFT
equations. We discuss important technical aspects of the DMFT-QMC which need to
be taken into account in order to obtain the reliable results near the
coexistence region. Among them are the critical slowing down of the iterative
solutions near phase boundaries, the convergence criteria for the DMFT
iterations, the interpolation of the discretized Green's function and the
reduction of QMC statistical and systematic errors. Comparison of our results
with those of other numerical methods is presented in a phase diagram.

</DOC>
<DOC>
<DOCNO> 150770 </DOCNO>
Noncommutative Field Theory and Spontaneous Symmetry Breaking


  We investigate the noncommutative analogue of the spontaneously broken linear
sigma model at the one-loop quantum level. In the commutative case,
renormalization of a theory with a spontaneously broken continuous global
symmetry depends on cancellations that enable the limited set of counterterms
consistent with that symmetry to remove the divergences even after its
spontaneous breaking, while preserving the masslessness of the associated
Goldstone modes. In the noncommutative case, we find that these cancellations
are violated, and the renormalized one-loop correction to the inverse pion
propagator explicitly yields a mass shift which depends on the ultraviolet
cutoff. Thus, we cannot naively take the ultraviolet cutoff to infinity first,
and then take the external momentum to zero to verify Nambu-Goldstone symmetry
realization. However, from the Wilsonian perspective where the cutoff is fixed
and physical, the zero external momentum limit of the inverse pion propagator
still vanishes, and implies the masslessness of the pion fields at one-loop.
This is another demonstration of the failure of ultraviolet and infrared limits
to commute in noncommutative field theories, and signals the incompatibility of
Nambu-Goldstone symmetry realization with the continuum renormalization of
these theories.

</DOC>
<DOC>
<DOCNO> 70518 </DOCNO>
Phenomenology of the Electron Structure Function


  Advantages of introducing the electron structure function (ESF) in electron
induced processes are demonstrated. Contrary to the photon structure function
it is directly measured in such processes. At present energies a simultaneous
analysis of both the electron and the photon structure functions gives an
important test of the experimentally applied methods. Estimates of the ESF at
currently measured momenta are given. At very high momenta contributions from
$W$ and $Z$ bosons together with $\gamma$-$Z$ interference can be observed.
Predictions for next generation of experiments are given.

</DOC>
<DOC>
<DOCNO> 69148 </DOCNO>
Isospin Symmetry Breaking in Nuclei - ONS Anomaly


  We study the binding energy differences of the valence proton and neutron of
the mirror nuclei, $^{15}$O - $^{15}$N, $^{17}$F - $^{17}$O, $^{39}$Ca -
$^{39}$K and $^{41}$Sc - $^{41}$Ca, using the quark-meson coupling model. The
calculation involves nuclear structure and shell effects explicitly. It is
shown that binding energy differences of a few hundred keV arise from the
strong interaction, even after subtracting all electromagnetic corrections. The
origin of these differences may be ascribed to the charge symmetry breaking
effects set in the strong interaction through the u and d current quark mass
difference. In this report, we first review the quark-meson coupling model. In
particular, we discuss about the nucleon mass in nuclear medium. Then, we
present details of the charge symmetry breaking in finite nuclei, especially
the Okamoto-Nolen-Schiffer anomaly.

</DOC>
<DOC>
<DOCNO> 69485 </DOCNO>
Scale- and scheme-independent extension of Pade approximants; Bjorken


  A renormalization-scale-invariant generalization of the diagonal Pad\'e
approximants (dPA), developed previously, is extended so that it becomes
renormalization-scheme-invariant as well. We do this explicitly when two terms
beyond the leading order (NNLO, $\sim \alpha_s^3$) are known in the truncated
perturbation series (TPS). At first, the scheme dependence shows up as a
dependence on the first two scheme parameters $c_2$ and $c_3$. Invariance under
the change of the leading parameter $c_2$ is achieved via a variant of the
principle of minimal sensitivity. The subleading parameter $c_3$ is fixed so
that a scale- and scheme-invariant Borel transform of the resummation
approximant gives the correct location of the leading infrared renormalon pole.
The leading higher-twist contribution, or a part of it, is thus believed to be
contained implicitly in the resummation. We applied the approximant to the
Bjorken polarized sum rule (BjPSR) at $Q^2_{\rm ph}=5$ and $3 GeV^2$, for the
most recent data and the data available until 1997, respectively, and obtained
${\alpha}_s^{\bar MS}(M_Z^2)=0.119^{+0.003}_{-0.006}$ and
$0.113^{+0.004}_{-0.019}$, respectively. Very similar results are obtained with
the Grunberg's effective charge method and Stevenson's TPS principle of minimal
sensitivity, if we fix $c_3$-parameter in them by the aforementioned procedure.
The central values for ${\alpha}_s^{\bar MS}(M_Z^2)$ increase to 0.120 (0.114)
when applying dPA's, and 0.125 (0.118) when applying NNLO TPS.

</DOC>
<DOC>
<DOCNO> 13472 </DOCNO>
Magnetic properties of the frustrated AFM spinel ZnCr_2O_4 and the


  The $T$-dependence (2- 400 K) of the electron paramagnetic resonance (EPR),
magnetic susceptibility, $\chi (T)$, and specific heat, $C_{v}(T)$, of the
$normal$ antiferromagnetic (AFM) spinel ZnCr$_{2}$O$_{4}$ and the spin-glass
(SG) Zn$_{1-x}$Cd$_{x}$Cr$_{2}$O$_{4}$ ($x=0.05,0.10$) is reported. These
systems behave as a strongly frustrated AFM and SG with $% T_{N}$ $ \approx
T_{G}\approx 12$ K and -400 K $\gtrsim \Theta_{CW}\gtrsim -500$ K. At high-$T$
the EPR intensity follows the $\chi (T)$ and the $g$-value is $T$-independent.
The linewidth broadens as the temperature is lowered, suggesting the existence
of short range AFM correlations in the paramagnetic phase. For
ZnCr$_{2}$O$_{4}$ the EPR intensity and $\chi (T)$ decreases below 90 K and 50
K, respectively. These results are discussed in terms of nearest-neighbor
Cr$^{3+}$ (S $=3/2$%) spin-coupled pairs with an exchange coupling of $| J/k|
\approx $ 50 K. The appearance of small resonance modes for $T\lesssim 17$ K,
the observation of a sharp drop in $\chi (T)$ and a strong peak in $C_{v}(T)$
at $T_{N}=12$ K confirms, as previously reported, the existence of long range
AFM correlations in the low-$T$ phase. A comparison with recent neutron
diffraction experiments that found a near dispersionless excitation at 4.5 meV
for $T\lesssim T_{N}$ and a continuous gapless spectrum for $T\gtrsim T_{N}$,
is also given.

</DOC>
<DOC>
<DOCNO> 83049 </DOCNO>
Pattern Discovery and Computational Mechanics


  Computational mechanics is a method for discovering, describing and
quantifying patterns, using tools from statistical physics. It constructs
optimal, minimal models of stochastic processes and their underlying causal
structures. These models tell us about the intrinsic computation embedded
within a process---how it stores and transforms information. Here we summarize
the mathematics of computational mechanics, especially recent optimality and
uniqueness results. We also expound the principles and motivations underlying
computational mechanics, emphasizing its connections to the minimum description
length principle, PAC theory, and other aspects of machine learning.

</DOC>
<DOC>
<DOCNO> 120880 </DOCNO>
On the large-scale structure of galactic disks


  The disk positions for galaxies of various morphological and nuclear-activity
types (normal galaxies, QSO, Sy, E/S0, low-surface brightness galaxies, etc.)
on the "central surface brightness - exponential scalelength" plane are
considered. The stellar disks are shown to form a single sequence on this plane
over a wide range of surface brightnesses (\mu_0(I)=12-25) and sizes (h=10 pc -
100 kpc). The existence of this observed sequence can probably be explaned by a
combination of three factors: a disk-stability requirement, a limited total
disk luminosity, and observational selection. The model by Mo et al. (1998) for
disk formation in the CDM hierarchical-clustering scenario is shown to
satisfactorily reproduce the salient features of the galaxy disk distribution
on the "\mu_0 - h" plane.

</DOC>
<DOC>
<DOCNO> 118169 </DOCNO>
Constraints on Cluster Formation from Old Globular CLuster Systems


  The properties of old globular cluster systems (GCSs) in galaxy halos offer
unique insight into the physical processes that conspire to form any generic
star cluster, at any epoch. Presented here is a summary of the information
obtained from (1) the specific frequencies (total populations) and spatial
structures (density vs. galactocentric radius) of GCSs in early-type galaxies,
as they relate to the efficiency (or probability) of bound cluster formation,
and (2) the fundamental role of a scaling between cluster mass and energy among
Galactic globulars in setting their other structural correlations, and the
possible implications for star formation efficiency as a function of mass in
gaseous protoclusters.

</DOC>
<DOC>
<DOCNO> 122670 </DOCNO>
Star Formation and Selective Dust Extinction in Luminous Starburst


  We investigate the star formation and dust extinction properties of very
luminous infrared galaxies whose spectra display a strong Hdelta line in
absorption and a moderate [OII] emission (e[a] spectrum). This spectral
combination has been suggested to be a useful method to identify dusty
starburst galaxies at any redshift on the basis of optical data alone. We
compare the average e(a) optical spectrum with synthetic spectra that include
both the stellar and the nebular contribution, allowing dust extinction to
affect differentially the stellar populations of different ages. We find that
reproducing the e(a) spectrum requires the youngest stellar generations to be
significantly more extinguished by dust than older stellar populations, and
implies a strong ongoing star formation activity at a level higher than in
quiescent spirals. A model fitting the optical spectrum does not necessarily
produce the observed FIR luminosity and this can be explained by the existence
of stellar populations which are practically obscured at optical wavelengths.
Models in which dust and stars are uniformly mixed yield a reddening of the
emerging emission lines which is too low compared to observations: additional
foreground reddening is required.

</DOC>
<DOC>
<DOCNO> 13358 </DOCNO>
Mechanical Properties of a Model of Attractive Colloidal Solutions


  We review the nature of glass transitions and the glasses arising from a
square-well potential with a narrow and deep well. Our discussion is based on
the Mode Coupling Theory, and the predictions of glasses that we make refer to
the `ideal' glasses predicted by that theory. We believe that the square well
system well represents colloidal particles with attractive interactions
produced by grafted polymers, or depletion interactions. It has been recently
shown that two types of glass, an attractive and a repulsive one, are predicted
by MCT for this model. The former can form at quite low densities. Most of our
attention is directed at the mechanical properties of the glasses predicted by
this theory. In particular we calculate the elastic shear modulus at zero
frequency and the longitudinal stress modulus in the long wavelength limit.
Results for both are presented along the glass-liquid transition curves, and
their interesting behaviour is explained in terms of the underlying physics of
the system.

</DOC>
<DOC>
<DOCNO> 13546 </DOCNO>
Tunable decoherence in the vicinity of a normal metal-superconducting


  The decoherence rate of a quantum dot coupled to a fluctuating environment
described by a normal-metal superconductor junction is considered. The
density-density correlator at low frequencies constitutes the kernel which
enters the calculation of the phase coherence time. The density fluctuations
are connected to the finite frequency current-current correlations in the point
contact via the continuity equation. Below and above the gap, at zero
temperature the density correlator contains spatial oscillations at half of the
Fermi wave length on the normal side. As the bias crosses the superconducting
gap, the opening of new scattering channels enhances the decoherence rate
dramatically, suggesting the possibility of tuning the decoherence rate in a
controllable manner.

</DOC>
<DOC>
<DOCNO> 100436 </DOCNO>
Jacobi equations using a variational principle


  A variational principle is proposed for obtaining the Jacobi equations in
systems admitting a Lagrangian description. The variational principle gives
simultaneously the Lagrange equations of motion and the Jacobi variational
equations for the system. The approach can be of help in finding constants of
motion in the Jacobi equations as well as in analysing the stability of the
systems and can be related to the vertical extension of the Lagrangian
formalism. To exemplify two of such aspects, we uncover a constant of motion in
the Jacobi equations of autonomous systems and we recover the well-known
sufficient conditions of stability of two dimensional orbits in classical
mechanics.

</DOC>
<DOC>
<DOCNO> 120598 </DOCNO>
A strategy for finding gravitationally-lensed distant supernovae


  Distant Type Ia and II supernovae (SNe) can serve as valuable probes of the
history of the cosmic expansion and star formation, and provide important
information on their progenitor models. At present, however, there are few
observational constraints on the abundance of SNe at high redshifts. A major
science driver for the Next Generation Space Telescope (NGST) is the study of
such very distant supernovae. In this paper we discuss strategies for finding
and counting distant SNe by using repeat imaging of super-critical intermediate
redshift clusters whose mass distributions are well-constrained via modelling
of strongly-lensed features. For a variety of different models for the star
formation history and supernova progenitors, we estimate the likelihood of
detecting lensed SNe as a function of their redshift. In the case of a survey
conducted with HST, we predict a high probability of seeing a supernova in a
single return visit with either WFPC-2 or ACS, and a much higher probability of
detecting examples with z>1 in the lensed case. Most events would represent
magnified SNe II at z~1, and a fraction will be more distant examples. We
discuss various ways to classify such events using ground-based infrared
photometry. We demonstrate an application of the method using the HST archival
data and discuss the case of a possible event found in the rich cluster AC 114
(z=0.31).

</DOC>
<DOC>
<DOCNO> 152272 </DOCNO>
Twisted Sectors and Chern-Simons Terms in M-Theory Orbifolds


  It is shown that the twisted sector spectrum, as well as the associated
Chern-Simons interactions, can be determined on M-theory orbifold fixed planes
that do not admit gravitational anomalies. This is demonstrated for the
seven-planes arising within the context of an explicit $R^6 \times S^1/Z_2
\times T^4/Z_2$ orbifold, although the results are completely general. Local
anomaly cancellation in this context is shown to require fractional anomaly
data that can only arise from a twisted sector on the seven-planes, thus
determining the twisted spectrum up to a small ambiguity. These results open
the door to the construction of arbitrary M-theory orbifolds, including those
containing fixed four-planes which are of phenomenological interest.

</DOC>
<DOC>
<DOCNO> 120234 </DOCNO>
Moderate resolution near-infrared spectroscopy of cool stars: a new


  I present an atlas of near-infrared K-band spectra of 31 late-type giants and
supergiants, and two carbon stars. The spectra were obtained at resolving
powers of 830 and 2000, and have a signal-to-noise ratio of 100 or higher.
These data are complemented with results from similar existing libraries in
both K- and H-band, and are used to identify various tools useful for stellar
population studies at moderate resolution. I focus on several of the most
prominent absorption features and (1) investigate the effects of spectral
resolution on measurements of their equivalent width (EW), (2) examine the
variations with stellar parameters of the EWs, and (3) construct composite
indices as indicators of stellar parameters and of the contribution from excess
continuum sources commonly found in star-forming and AGN galaxies. Among the
features considered, the CO (2,0) and CO (6,3) bandheads together with the SiI
1.59 micron feature, first proposed by Oliva, Origlia, and coworkers,
constitute the best diagnostic set for stellar spectral classification and for
constraining the excess continuum emission. The CaI 2.26 micron and MgI 2.28
micron features offer alternatives in the K-band to the CO (6,3) bandhead and
SiI feature.

</DOC>
<DOC>
<DOCNO> 13086 </DOCNO>
Anomalous NMR Spin-Lattice Relaxation in SrB_{6} and Ca_{1-x}La_{x}B_{6}


  We report the results of {11}B nuclear magnetic resonance (NMR) measurements
of SrB_{6} and Ca_{0.995}La_{0.05}B_{6} below room temperature. Although the
electrical resistivities of these two materials differ substantially, their
{11}B-NMR responses exhibit some strikingly common features. Both materials
exhibit ferromagnetic order, but their {11}B-NMR spectra reveal very small
hyperfine fields at the Boron sites. The spin lattice relaxation T_{1}^{-1}
varies considerably with external field but changes with temperature only below
a few K. We discuss these unusual results by considering various different
scenarios for the electronic structure of these materials.

</DOC>
<DOC>
<DOCNO> 8667 </DOCNO>
Coulomb Charging Effects in an Open Quantum Dot


  Low-temperature transport properties of a lateral quantum dot formed by
overlaying finger gates in a clean one-dimensional channel are investigated.
Continuous and periodic oscillations superimposed upon ballistic conductance
steps are observed, when the conductance G of the dot changes within a wide
range 0<G<6e^2/h. Calculations of the electrostatics confirm that the measured
periodic conductance oscillations correspond to successive change of the total
charge of the dot by $e$. By modelling the transport it is shown that the
progression of the Coulomb oscillations into the region G>2e^2/h may be due to
suppression of inter-1D-subband scattering. Fully transmitted subbands
contribute to coherent background of conductance, while sequential tunneling
via weakly transmitted subbands leads to Coulomb charging of the dot.

</DOC>
<DOC>
<DOCNO> 102514 </DOCNO>
Disjunctive Quantum Logic in Dynamic Perspective


  In arXiv: math.LO/0011208 we proposed the {\sl intuitionistic or disjunctive
representation of quantum logic}, i.e., a representation of the property
lattice of physical systems as a complete Heyting algebra of logical
propositions on these properties, where this complete Heyting algebra goes
equipped with an additional operation, the {\sl operational resolution}, which
identifies the properties within the logic of propositions. This representation
has an important application ``towards dynamic quantum logic'', namely in
describing the temporal indeterministic propagation of actual properties of
physical systems. This paper can as such by conceived as an addendum to
``Quantum Logic in Intuitionistic Perspective'' that discusses spin-off and
thus provides an additional motivation. We derive a quantaloidal semantics for
dynamic disjunctive quantum logic and illustrate it for the particular case of
a perfect (quantum) measurement.

</DOC>
<DOC>
<DOCNO> 9275 </DOCNO>
New Classes of Quasicrystals and Marginal Critical States


  One-dimensional quasilattices, namely, the geometrical objects to represent
quasicrystals, are classified into mutual local-derivability (MLD) classes.
Besides the familiar class, there exist an infinite number of new MLD classes,
and different MLD classes are distinguished by the inflation rules of their
representatives. It has been found that electronic properties of a new MLD
class are characterized by the presence of marginal critical states, which are
considered to be nearly localized states.

</DOC>
<DOC>
<DOCNO> 68116 </DOCNO>
Sterile Neutrinos in Big Bang Nucleosynthesis


  We investigate analytically the evolution of the primordial neutrino
asymmetry caused by active-sterile neutrino oscillations. In particular, we
concentrate on possible chaotic oscillations of the asymmetry. For a certain
range of parameters, we find that the asymmetry indeed oscillates, provided we
neglect the momentum distribution.

</DOC>
<DOC>
<DOCNO> 10452 </DOCNO>
Coherent quasiparticle weight and its connection to high-T_c


  In conventional superconductors, the pairing energy gap (\Delta) and
superconducting phase coherence go hand-in-hand. As the temperature is lowered,
both the energy gap and phase coherence appear at the transition temperature
T_c. In contrast, in underdoped high-T_c superconductors (HTSCs), a pseudogap
appears at a much higher temperature T^*, smoothly evolving into the
superconducting gap at T_c. Phase coherence on the other hand is only
established at T_c, signaled by the appearance of a sharp quasiparticle (QP)
peak in the excitation spectrum. Another important difference between the two
types of superconductors is in the ratio of 2\Delta / T_c=R. In BCS theory,
R~3.5, is constant. In the HTSCs this ratio varies widely, continuing to
increase in the underdoped region, where the gap increases while T_c decreases.
Here we report that in HTSCs it is the ratio z_A\Delta_m/T_c which is
approximately constant, where \Delta_m is the maximum value of the d-wave gap,
and z_A is the weight of the coherent excitations in the spectral function.
This is highly unusual, since in nearly all phase transitions, T_c is
determined by an energy scale alone. We further show that in the
low-temperature limit, z_{\it A} increases monotonically with increasing doping
x. The growth is linear, i.e. z_A(x)\propto x, in the underdoped to optimally
doped regimes, and slows down in overdoped samples. The reduction of z_A with
increasing temperature resembles that of the c-axis superfluid density.

</DOC>
<DOC>
<DOCNO> 7612 </DOCNO>
Non-equilibrium growth for a restricted-curvature model


  The static and dynamic roughenings of a growing crystalline facet is studied
where the growth mechanism is controlled by a restricted-curvature (RC)
geometry. A continuum equation, in analogy with the Kardar-Parisi-Zhang (KPZ)
equation is considered for the purpose. It is shown here that although the
growth process begins with a RC geometry, a structural phase transition occurs
from the restricted-curvature phase to the KPZ phase. An estimation of the
corresponding critical temperature is given here. Calculations on the static
phase transition give results along the same line as existing predictions,
apart fromm minor numerical adjustments.

</DOC>
<DOC>
<DOCNO> 151441 </DOCNO>
Localization of Quantum Fields on Branes


  A mechanism for localization of quantum fields on a $s$-brane, representing
the boundary of a s+2 dimensional bulk space, is investigated. Minkowski and
AdS bulk spaces are analyzed. Besides the background geometry, the relevant
parameters controlling the theory are the mass M and a real parameter \eta,
specifying the boundary condition on the brane. The importance of exploring the
whole range of allowed values for these parameters is emphasized. Stability in
Minkowski space requires \eta to be greater or equal to -M, whereas in the AdS
background all real \eta are permitted. Both in the flat and in AdS case, the
induced field on the brane is a non-canonical generalized free field. For a
suitable choice of boundary condition, corresponding to the presence of a
boundary state, the induced field on the brane mimics standard s+1 dimensional
physics. In a certain range of \eta, the spectral function in the the AdS case
is ominated by a massive excitation, which imitates the presence of massive
particle on the brane. We show that the quantum field induced on the brane is
stable.

</DOC>
<DOC>
<DOCNO> 118927 </DOCNO>
A Merger Scenario for the Dynamics of Abell 665


  We present new redshift measurements for 55 galaxies in the vicinity of the
rich galaxy cluster Abell 665. When combined with results from the literature,
we have good velocity measurements for a sample of 77 confirmed cluster members
from which we derive the cluster's redshift z=0.1829 +/- 0.0005 and
line-of-sight velocity dispersion of 1390 +/- 120 km/s. Our analysis of the
kinematical and spatial data for the subset of galaxies located within the
central 750 kpc reveals only subtle evidence for substructure and
non-Gaussianity in the velocity distribution. We find that the brightest
cluster member is not moving significantly relative to the other galaxies near
the center of the cluster. On the other hand, our deep ROSAT high resolution
image of A665 shows strong evidence for isophotal twisting and centroid
variation, thereby confirming previous suggestions of significant substructure
in the hot X-ray--emitting intracluster gas. In light of this evident
substructure, we have compared the optical velocity data with N-body
simulations of head-on cluster mergers. We find that a merger of two similar
mass subclusters (mass ratios of 1:1 or 1:2) seen close to the time of
core-crossing produces velocity distributions that are consistent with that
observed.

</DOC>
<DOC>
<DOCNO> 169836 </DOCNO>
Recovering Coherence via Conditional Measurements


  We show that conditional measurements on atoms following their interaction
with a resonant cavity field mode can be used to effectively counter the
decoherence of Fock-state superpositions due to cavity leakage.

</DOC>
<DOC>
<DOCNO> 10507 </DOCNO>
Dynamics of Forster Energy Migration Across Polymer Chains in Solution


  Long distance excitation energy transfer between a donor and an acceptor
embedded in a polymer chain is usually assumed to occur via the Forster
mechanism which predicts a 1/R^6 distance dependence of the transfer rate,
where R is the distance between the donor and the acceptor. In solution R
fluctuates with time. In this work, a Brownian dynamics simulation of a polymer
chain with Forster enregy transfer between the two ends is carried out and the
time dependence of the survival probability S_p(t) is obtained. The latter can
be measured by the flourescence resonance energy transfer (FRET) technique,
which is now widely used to study conformations of biopolymers via the single
molecule spectroscopy. It is found that the suvival probability is
exponential-like when the Forster radius (R_F) is comparable to the root mean
square radius(L) of the polymer chain. The decay is strongly non-exponential
both for small and large (R_F), and also for large k_F. Large deviations from
Wilemski-Fixman theory is obtained when R_F is significantly differnet from L.

</DOC>
<DOC>
<DOCNO> 9015 </DOCNO>
Fluctuation-dissipation relation in a sheared fluid


  In a fluid out of equilibrium, the fluctuation dissipation theorem (FDT) is
usually violated. Using molecular dynamics simulations, we study in detail the
relationship between correlation and response functions in a fluid driven into
a stationary non-equilibrium state. Both the high temperature fluid state and
the low temperature glassy state are investigated. In the glassy state, the
violation of the FDT is quantitatively identical to the one observed previously
in an aging system in the absence of external drive. In the fluid state,
violations of the FDT appear only when the fluid is driven beyond the linear
response regime, and are then similar to those observed in the glassy state.
These results are consistent with the picture obtained earlier from theoretical
studies of driven mean-field disordered models, confirming the similarity
between these models and real glasses.

</DOC>
<DOC>
<DOCNO> 123032 </DOCNO>
Effective stability of the Trojan asteroids


  We study the spatial circular restricted problem of three bodies in the light
of Nekhoroshev theory of stability over large time intervals. We consider in
particular the Sun-Jupiter model and the Trojan asteroids in the neighborhood
of the Lagrangian point $L_4$. We find a region of effective stability around
the point $L_4$ such that if the initial point of an orbit is inside this
region the orbit is confined in a slightly larger neighborhood of the
equilibrium (in phase space) for a very long time interval. By combining
analytical methods and numerical approximations we are able to prove that
stability over the age of the universe is guaranteed on a realistic region, big
enough to include one real asteroid. By comparing this result with the one
obtained for the planar problem we see that the regions of stability in the two
cases are of the same magnitude.

</DOC>
<DOC>
<DOCNO> 117966 </DOCNO>
Intrinsic constraints on very high energy emission in gamma-ray loud


  Photons with very high energy up to TeV (VHE) emitted from active galactic
nuclei (AGNs) provide some invaluable information of the origin of $\gam$-ray
emission. Although 66 blazars have been detected by {\it EGRET}, only three low
redshift X-ray selected BL Lacs (Mrk 421, Mrk 501, and 1ES 2344+514) are
conclusive TeV emitters (PKS 2155-304 is a potential TeV emitter) since VHE
photons may be absorbed by cosmological background infrared photons ({\it
external} absorption). Based on the ``mirror'' effect of clouds in broad line
region, we argue that there is an {\it intrinsic} mechanism for the deficiency
of TeV emission in blazars. Employing the observable quantities we derive the
pair production optical depth $\tgg(\eps_{\rm obs})$ due to the interaction of
VHE photons with the reflected synchrotron photons by electron Thomson
scattering in broad line region. This sets a more strong constraints on very
high energy emission, and provides a sensitive upper limit of Doppler factor of
the relativistic bulk motion. It has been suggested to distinguish the {\it
intrinsic} absorption from the {\it external} by the observation on variation
of multiwavelegenth continuum.

</DOC>
<DOC>
<DOCNO> 119842 </DOCNO>
Formulae for Growth Factors In Expanding Universes Containing Matter and


  Formulae are presented for the linear growth factor D/a and its logarithmic
derivative dlnD/dlna in expanding Friedmann-Robertson-Walker Universes with
arbitrary matter and vacuum densities. The formulae permit rapid and stable
numerical evaluation. A fortran program is available at
http://casa.colorado.edu/~ajsh/growl/ .

</DOC>
<DOC>
<DOCNO> 118601 </DOCNO>
Nonthermal Emission from a Supernova Remnant in a Molecular Cloud


  In evolved supernova remnants (SNRs) interacting with molecular clouds, such
as IC 443, W44, and 3C391, a highly inhomogeneous structure consisting of a
forward shock of moderate Mach number, a cooling layer, a dense radiative shell
and an interior region filled with hot tenuous plasma is expected. We present a
kinetic model of nonthermal electron injection, acceleration and propagation in
that environment and find that these SNRs are efficient electron accelerators
and sources of hard X- and gamma-ray emission. The energy spectrum of the
nonthermal electrons is shaped by the joint action of first and second order
Fermi acceleration in a turbulent plasma with substantial Coulomb losses.
Bremsstrahlung, synchrotron, and inverse Compton radiation of the nonthermal
electrons produce multiwavelength photon spectra in quantitative agreement with
the radio and the hard emission observed by ASCA and EGRET from IC 443. We
distinguish interclump shock wave emission from molecular clump shock wave
emission accounting for a complex structure of molecular cloud. Spatially
resolved X- and gamma- ray spectra from the supernova remnants IC 443, W44, and
3C391 as might be observed with BeppoSAX, Chandra XRO, XMM, INTEGRAL and GLAST
would distinguish the contribution of the energetic lepton component to the
gamma-rays observed by EGRET.

</DOC>
<DOC>
<DOCNO> 11053 </DOCNO>
Exact Solution of the strong coupling t-V model with twisted boundary


  We present the solution of the one-dimensional t-V model with twisted
boundary conditions in the strong coupling limit, t<<V and show that this model
can be mapped onto the strong coupling Hubbard chain threaded by a fictitious
flux proportional to the total momentum of the charge carriers. The high energy
eigenstates are characterized by a factorization of degrees of freedom
associated with configurations of soliton and antisoliton domains and degrees
of freedom associated with the movement of ``holes'' through these domains. The
coexistence of solitons and antisolitons leads to a strange flux dependence of
the eigenvalues. We illustrate the use of this solution, deriving the full
frequency dependence of the optical conductivity at half-filling and zero
temperature.

</DOC>
<DOC>
<DOCNO> 101976 </DOCNO>
Variations on a conjecture of Halperin


  Halperin has conjectured that the Serre spectral sequence of any fibration
that has fibre space a certain kind of elliptic space should collapse at the
E_2-term. In this paper we obtain an equivalent phrasing of this conjecture, in
terms of formality relations between base and total spaces in such a fibration
(Theorem 3.4). Also, we obtain results on relations between various
numericalinvariants of the base, total and fibre spaces in these fibrations.
Some of our results give weak versions of Halperin's conjecture (Remark 4.4 and
Corollary 4.5). We go on to establish some of these weakened forms of the
conjecture (Theorem 4.7). In the last section, we discuss extensions of our
results and suggest some possibilities for future work.

</DOC>
<DOC>
<DOCNO> 169838 </DOCNO>
Quantum Computation with hot and cold ions:An assessment of proposed


  We present a brief critical review of the proposals for quantum computation
with trapped ions, with particular emphasis on the possibilities for quantum
computation without the need for cooling to the quantum ground state of the
ions' collective oscillatory modes.

</DOC>
<DOC>
<DOCNO> 69283 </DOCNO>
Charm Production in Deep Inelastic Scattering from Threshold to High


  Charm final states in deep inelastic scattering constitute $\sim 25%$ of the
inclusive cross-section at small $x$ as measured at HERA. These data can reveal
important information on the charm and gluon structure of the nucleon if they
are interpreted in a consistent perturbative QCD framework which is valid over
the entire energy range from threshold to the high energy limit. We describe in
detail how this can be carried out order-by-order in PQCD in the generalized
\msbar formalism of Collins (generally known as the ACOT approach), and
demonstrate the inherent smooth transition from the 3-flavor to the 4-flavor
scheme in a complete order $\alpha_s$ calculation, using a Monte Carlo
implementation of this formalism. This calculation is accurate to the same
order as the conventional NLO $F_2$ calculation in the limit $\frac{Q}{m_c} >>
1$. It includes the resummed large logarithm contributions of the 3-flavor
scheme (generally known in this context as the fixed-flavor-number or FFN
scheme) to all orders of $\alpha_s\ln(m_c^2/Q^2)$. For the inclusive structure
function, comparison with recent HERA data and the existing FFN calculation
reveals that the relatively simple order-$\alpha_s$ (NLO) 4-flavor ($m_c \neq
0$) calculation can, in practice, be extended to rather low energy scales,
yielding good agreement with data over the full measured $Q^2$ range. The Monte
Carlo implementation also allows the calculation of differential distributions
with relevant kinematic cuts. Comparisons with available HERA data show
qualitative agreement; however, they also indicate the need to extend the
calculation to the next order to obtain better description of the differential
distributions.

</DOC>
<DOC>
<DOCNO> 118841 </DOCNO>
Resolving SNR 0540-6944 from LMC X-1 with Chandra


  We examine the supernova remnant (SNR) 0540-697 in the Large Magellanic Cloud
(LMC) using data from the Chandra ACIS. The X-ray emission from this SNR had
previously been hidden in the bright emission of nearby X-ray binary LMC X-1;
however, new observations with Chandra can finally reveal the SNR's structure
and spectrum. We find the SNR to be a thick-shelled structure about 19 pc in
diameter, with a brightened northeast region. Spectral results suggest a
temperature of 0.31 keV and an X-ray luminosity (0.3-3.0 keV) of 8.4 x 10^33
erg/s. We estimate an age of 12,000-20,000 yr for this SNR, but note that this
estimate does not take into account the possibility of cavity expansion or
other environmental effects.

</DOC>
<DOC>
<DOCNO> 11461 </DOCNO>
Luttinger liquid behavior in metallic carbon nanotubes


  Coulomb interaction effects have pronounced consequences in carbon nanotubes
due to their 1D nature. In particular, correlations imply the breakdown of
Fermi liquid theory and typically lead to Luttinger liquid behavior
characterized by pronounced power-law suppression of the transport current and
the density of states, and spin-charge separation. This paper provides a review
of the current understanding of non-Fermi liquid effects in metallic
single-wall nanotubes (SWNTs). We provide a self-contained theoretical
discussion of electron-electron interaction effects and show that the tunneling
density of states exhibits power-law behavior. The power-law exponent depends
on the interaction strength parameter $g$ and on the geometry of the setup.
 We then show that these features are observed experimentally by measuring the
tunneling conductance of SWNTs as a function of temperature and voltage. These
tunneling experiments are obtained by contacting metallic SWNTs to two
nanofabricated gold electrodes. Electrostatic force microscopy (EFM)
measurements show that the measured resistance is due to the contact resistance
from the transport barrier formed at the electrode/nanotube junction. These EFM
measurements show also the ballistic nature of transport in these SWNTs. While
charge transport can be nicely attributed to Luttinger liquid behavior,
spin-charge separation has not been observed so far. We briefly describe a
transport experiment that could provide direct evidence for spin-charge
separation.

</DOC>
<DOC>
<DOCNO> 170113 </DOCNO>
From the quantum Zeno to the inverse quantum Zeno effect


  The temporal evolution of an unstable quantum mechanical system undergoing
repeated measurements is investigated. In general, by changing the time
interval between successive measurements, the decay can be accelerated (inverse
quantum Zeno effect) or slowed down (quantum Zeno effect), depending on the
features of the interaction Hamiltonian. A geometric criterion is proposed for
a transition to occur between these two regimes.

</DOC>
<DOC>
<DOCNO> 118349 </DOCNO>
Gas and dust in NGC 7469: sub-mm imaging and CO J=3-2


  We present sensitive sub-mm imaging of the Seyfert 1 galaxy NGC 7469 at 850
$\mu $m and 450 $\mu $m with the Submillimetre Common User Bolometer Array
(SCUBA) on the James Clerk Maxwell Telescope (JCMT) and ^{12}CO J=3-2 line
observations of its central starbursting region. The global dust spectrum, as
constrained by the new set of sub-mm data and available 1.30 mm and IRAS 100
$\mu $m, 60 $\mu $m data reveals a dominant warm dust component with a
temperature of $\rm T_{\rm d} \sim 35$ K and a global molecular gas-to-dust
ratio $\rm M(H_2)/M_{\rm d}\sim 600$. Such high values are typical for
IR-bright spirals and in order to reconcile them with the significantly lower
ratio of ~ 100 obtained for the Milky Way a cold dust reservoir, inconspicuous
at FIR wavelengths, is usually postulated. We present evidence that, rather
than unaccounted cold dust mass, this high ratio suggests an overestimate of
$\rm M(H_2)$ from its associated ^{12}CO J=1-0 line luminosity by a factor of ~
5 when a Milky Way value for this conversion is used in starburst nuclei
environments.

</DOC>
<DOC>
<DOCNO> 170800 </DOCNO>
Optimum unambiguous discrimination among linearly-independent


  The problem of unambiguously distinguishing among nonorthogonal but linearly
independent quantum states can be solved by mapping the set of nonorthogonal
quantum states onto a set of orthogonal ones, which can then be distinguished
without error. Such nonunitary transformations can be performed conditionally
on quantum systems; a unitary transformation is carried out on a larger system
of which the system of interest is a subsytem, a measurement is performed, and
if the proper result is obtained, the desired nonunitary transformation will
have been performed on the subsystem. We show how to construct generalized
interferometers (multiports), which when combined with measurements on some of
the output ports, implement nonunitary transformations of this type. The input
states are single-photon states in which the photon is divided among several
modes. A number of explicit examples of distinguishing among three
nonorthogonal states are discussed, and the networks that optimally distinguish
among these states are presented.

</DOC>
<DOC>
<DOCNO> 69184 </DOCNO>
High energy QCD and hard diffraction at HERA versus Tevatron


  We present and discuss two different topics where Tevatron and HERA data can
be compared directly. A method allowing for a direct comparison of data with
theoretical predictions is proposed for forward jet production at HERA. An
application to the determination of the effective Pomeron intercept in the
BFKL-LO parametrization from $d\sigma/dx$ data at HERA leads to a good fit with
a significantly high effective intercept, $\alpha_P= 1.43 \pm 0.025 (stat.) \pm
0.025 (syst.)$. It is less than the value of the pomeron intercept using dijets
with large rapidity intervals obtained at Tevatron. In a second part of this
report, we make comparison between diffractive results at HERA and at Tevatron.
We first give the parton distributions in the pomeron extracted from HERA data,
and compare with hard single diffraction at Tevatron and diffractive dijets
with a leading antiproton data.

</DOC>
<DOC>
<DOCNO> 68959 </DOCNO>
Cosmological constraints on R-parity violation from neutrino decay


  If the neutrino mass is non-zero, as hinted by several experiments, then
R-parity-violating supersymmetric Yukawa couplings can drive a heavy neutrino
decay into lighter states. The heavy neutrino may either decay radiatively into
a lighter neutrino, or it may decay into three light neutrinos through a
Z-mediated penguin. For a given mass of the decaying neutrino, we calculate its
lifetime for the various modes, each mode requiring certain pairs of
R-parity-violating couplings be non-zero. We then check whether the calculated
lifetimes fall in zones allowed or excluded by cosmological requirements. For
the latter case, we derive stringent new constraints on the corresponding
products of R-parity-violating couplings for given values of the decaying
neutrino mass.

</DOC>
<DOC>
<DOCNO> 84665 </DOCNO>
Cylindrically symmetric dust spacetime


  We present an explicit exact solution of Einstein's equations for an
inhomogeneous dust universe with cylindrical symmetry. The spacetime is
extremely simple but nonetheless it has new surprising features. The universe
is ``closed'' in the sense that the dust expands from a big-bang singularity
but recollapses to a big-crunch singularity. In fact, both singularities are
connected so that the whole spacetime is ``enclosed'' within a single
singularity of general character. The big-bang is not simultaneous for the
dust, and in fact the age of the universe as measured by the dust particles
depends on the spatial position, an effect due to the inhomogeneity, and their
total lifetime has no non-zero lower limit. Part of the big-crunch singularity
is naked. The metric depends on a parameter and contains flat spacetime as a
non-singular particular case. For appropriate values of the parameter the
spacetime is a small perturbation of Minkowski spacetime. This seems to
indicate that flat spacetime may be unstable against some global {\it
non-vacuum} perturbations.

</DOC>
<DOC>
<DOCNO> 102235 </DOCNO>
Vanishing Theorems and String Backgrounds


  We show various vanishing theorems for the cohomology groups of compact
hermitian manifolds for which the Bismut connection has (restricted) holonomy
contained in SU(n) and classify all such manifolds of dimension four. In this
way we provide necessary conditions for the existence of such structures on
hermitian manifolds. Then we apply our results to solutions of the string
equations and show that such solutions admit various cohomological restrictions
like for example that under certain natural assumptions the plurigenera vanish.
We also find that under some assumptions the string equations are equivalent to
the condition that a certain vector is parallel with respect to the Bismut
connection.

</DOC>
<DOC>
<DOCNO> 83353 </DOCNO>
A Learning Approach to Shallow Parsing


  A SNoW based learning approach to shallow parsing tasks is presented and
studied experimentally. The approach learns to identify syntactic patterns by
combining simple predictors to produce a coherent inference. Two instantiations
of this approach are studied and experimental results for Noun-Phrases (NP) and
Subject-Verb (SV) phrases that compare favorably with the best published
results are presented. In doing that, we compare two ways of modeling the
problem of learning to recognize patterns and suggest that shallow parsing
patterns are better learned using open/close predictors than using
inside/outside predictors.

</DOC>
<DOC>
<DOCNO> 101234 </DOCNO>
Fractional Supersymmetry and Lie Algebras


  Supersymmetry and super-Lie algebras have been consistently generalized
previously. The so-called fractional supersymmetry and $F-$Lie algebras could
be constructed starting from any representation $\D$ of any Lie algebra $g$.
This involves taking the $F^{\mathrm th}$ root of $\D$ in some sense. We show,
after having constructed differential realization(s) of any Lie algebra, how
fractional supersymmetry can be explicitly realized in terms of appropriate
homogeneous monomials.

</DOC>
<DOC>
<DOCNO> 99417 </DOCNO>
Analytic Topology of Groups, Actions, Strings and Varietes


  This is a paper in Analytic Topology.

</DOC>
<DOC>
<DOCNO> 123242 </DOCNO>
Colors of 2625 Quasars at 0<z<5 Measured in the Sloan Digital Sky Survey


  We present an empirical investigation of the colors of quasars in the Sloan
Digital Sky Survey (SDSS) photometric system. The sample studied includes 2625
quasars with SDSS photometry. The quasars are distributed in a 2.5 degree wide
stripe centered on the Celestial Equator covering $\sim529$ square degrees.
Positions and SDSS magnitudes are given for the 898 quasars known prior to SDSS
spectroscopic commissioning. New SDSS quasars represent an increase of over
200% in the number of known quasars in this area of the sky. The ensemble
average of the observed colors of quasars in the SDSS passbands are well
represented by a power-law continuum with $\alpha_{\nu} = -0.5$ ($f_{\nu}
\propto \nu^{\alpha}$). However, the contributions of the $3000 {\rm \AA}$ bump
and other strong emission lines have a significant effect upon the colors. The
color-redshift relation exhibits considerable structure, which may be of use in
determining photometric redshifts for quasars. The range of colors can be
accounted for by a range in the optical spectral index with a distribution
$\alpha_{\nu}=-0.5\pm0.65$ (95% confidence), but there is a red tail in the
distribution. This tail may be a sign of internal reddening. Finally, we show
that there is a continuum of properties between quasars and Seyfert galaxies
and we test the validity of the traditional division between the two classes of
AGN.

</DOC>
<DOC>
<DOCNO> 12028 </DOCNO>
Muon Spin Relaxation Study of (La, Ca)MnO3


  We report predominantly zero field muon spin relaxation measurements in a
series of Ca-doped LaMnO_3 compounds which includes the colossal
magnetoresistive manganites. Our principal result is a systematic study of the
spin-lattice relaxation rates 1/T_1 and magnetic order parameters in the series
La_{1-x}Ca_xMnO_3, x = 0.0, 0.06, 0.18, 0.33, 0.67 and 1.0. In LaMnO_3 and
CaMnO_3 we find very narrow critical regions near the Neel temperatures T_N and
temperature independent 1/T_1 values above T_N. From the 1/T_1 in LaMnO_3 we
derive an exchange integral J = 0.83 meV which is consistent with the mean
field expression for T_N. All of the doped manganites except CaMnO_3 display
anomalously slow, spatially inhomogeneous spin-lattice relaxation below their
ordering temperatures. In the ferromagnetic (FM) insulating
La_{0.82}Ca_{0.18}MnO_3 and ferromagnetic conducting La_{0.67}Ca_{0.33}MnO_3
systems we show that there exists a bi-modal distribution of \muSR rates
\lambda_f and \lambda_s associated with relatively 'fast' and 'slow' Mn
fluctuation rates, respectively. A physical picture is hypothesized for these
FM phases in which the fast Mn rates are due to overdamped spin waves
characteristic of a disordered FM, and the slower Mn relaxation rates derive
from distinct, relatively insulating regions in the sample. Finally, likely
muon sites are identified, and evidence for muon diffusion in these materials
is discussed.

</DOC>
<DOC>
<DOCNO> 102660 </DOCNO>
Topology of U(2,1) representation spaces


  We calculate the Betti numbers of moduli spaces of representations of a
universal central extension of a surface group in the groups U(2,1) and
SU(2,1). In order to obtain our results we use the identification of this space
with an appropriate moduli space of Higgs bundles, and Morse theory, following
Hitchin's calculation of the Betti numbers of the moduli space of rank 2 Higgs
bundles. This requires a careful analysis of critical submanifolds which turn
out to have a description using either symmetric products of the surface or
moduli spaces of Bradlow pairs.

</DOC>
<DOC>
<DOCNO> 121448 </DOCNO>
Differences between the Two Anomalous X-Ray Pulsars: Variations in the


  We analysed the RXTE archival data of 1E 1048.1-5937 covering a time span of
more than one year. The spin down rate of this source decreases by 30 percent
during the observation. We could not resolve the X-ray flux variations because
of contamination by Eta Carinae. We find that the level of pulse frequency
fluctuations of 1E 1048.1-5937 is consistent with typical noise levels of
accretion powered pulsars. Recent RXTE observations of 1E 2259+586 have shown a
constant spin down with a very low upper limit on timing noise. We used the
RXTE archival X-ray observations of 1E 2259+586 to show that the intrinsic
X-ray luminosity times series is also stable, with an rms fractional variation
of less than 15 percent. The source could have been in a quiet phase of
accretion with a constant X-ray luminosity and spin down rate.

</DOC>
<DOC>
<DOCNO> 178793 </DOCNO>
To the nature of intermediate- and short-range nucleon-nucleon


  Instead of the Yukawa mechanism for intermediate- and short-range interaction
some new approach based on formation of the symmetric six-quark bag in the
state $|(0s)^6[6]_X,L=0>$ dressed due to strong coupling to $\pi$, $\sigma$ and
$\rho$ fields are suggested. This new mechanism offers both a strong
intermediate-range attraction which replaces the effective $\sigma$-exchange
(or excitation of two isobars in the intermediate state) in traditional force
models and also short-range repulsion. Simple illustrative model is developed
which demonstrates clearly how well the suggested new mechanism can reproduce
$NN$ data.

</DOC>
<DOC>
<DOCNO> 116712 </DOCNO>
The non-retarded dispersive force between an electrically polarizable


  Using perturbative QED we show that, while the retarded dispersive force
between an electrically polarizable atom and a magnetically polarizable one is
proportional to $1/r^{8}$, where $r$ is the distance between the atoms, the
non-retarded force is proportiaonal to $1/r^{5}$. This is a rather surprising
result that should be compared with the dispersive van der Waals force between
two electrically polarizable atoms, where the retarded force is also
proportional to $1/r^{8}$, but the non-retarded force is proportional to
$1/r^{7}$.

</DOC>
<DOC>
<DOCNO> 12142 </DOCNO>
High-frequency Cross-correlation in a Set of Stocks


  The high-frequency cross-correlation existing between pairs of stocks traded
in a financial market are investigated in a set of 100 stocks traded in US
equity markets. A hierarchical organization of the investigated stocks is
obtained by determining a metric distance between stocks and by investigating
the properties of the subdominant ultrametric associated with it. A clear
modification of the hierarchical organization of the set of stocks investigated
is detected when the time horizon used to determine stock returns is changed.
The hierarchical location of stocks of the energy sector is investigated as a
function of the time horizon.

</DOC>
<DOC>
<DOCNO> 118209 </DOCNO>
On the evolution of young radio-loud AGN


  This paper describes an investigation of the early evolution of extragalactic
radio sources using samples of faint and bright Gigahertz Peaked Spectrum (GPS)
and Compact Steep Spectrum (CSS) radio galaxies. Correlations found between
their peak frequency, peak flux density and angular size provide strong
evidence that synchrotron self absorption is the cause of the spectral
turnovers, and indicate that young radio sources evolve in a self-similar way.
In addition, the data seem to suggest that the sources are in equipartition
while they evolve. If GPS sources evolve to large size radio sources, their
redshift dependent birth-functions should be the same. Therefore, since the
lifetimes of radio sources are thought to be short compared to the Hubble time,
the observed difference in redshift distribution between GPS and large size
sources must be due to a difference in slope of their luminosity functions. We
argue that this slope is strongly affected by the luminosity evolution of the
individual sources. A scenario for the luminosity evolution is proposed in
which GPS sources increase in luminosity and large scale radio sources decrease
in luminosity with time. This evolution scenario is expected for a ram-pressure
confined radio source in a surrounding medium with a King profile density. In
the inner parts of the King profile, the density of the medium is constant and
the radio source builds up its luminosity, but after it grows large enough the
density of th e surrounding medium declines and the luminosity of the radio
source decreases. A comparison of the local luminosity function (LLF) of GPS
galaxies with that of extended sources is a good test for this evolution
scenario [abridged].

</DOC>
<DOC>
<DOCNO> 102090 </DOCNO>
Inverse Problem for semisimple Frobenius Manifolds, Monodromy Data and


  We study critical behaviour and connection problem for a Painleve' 6
equation. We construct solutions of WDVV eqs. using the isomonodromic
deformation method and the Painleve' equations. We find algebraic solutions of
WDVV and Gromov-Witten invariants of projective space.

</DOC>
<DOC>
<DOCNO> 9550 </DOCNO>
Polarons


  A conduction electron (or hole) together with its self-induced polarisation
in a polar semiconductor or an ionic crystal forms a quasi-particle, which is
called a polaron. The polaron concept is of interest, not only because it
describes the particular physical properties of charge carriers in polarizable
solids but also because it constitutes an interesting field theoretical model
of a fermion interacting with a scalar boson field. The early work on polarons
was concerned with general theoretical formulations and approximations, which
now constitute the standard polaron theory, and with experiments on cyclotron
resonance and transport properties. Because of the more recent interest in the
two-dimensional electron gas, the study of the polaron in two dimensions became
important. Again cyclotron resonance, and therefore the behaviour of polarons
in magnetic fields, was a key issue. When two electrons (or two holes) interact
with each other simultaneously through the Coulomb force and via the
electron-phonon-electron interaction, either two independent polarons can occur
or a bound state of two polarons - a bipolaron - can arise. Bipolarons have
been considered to possibly play a role in high-Tc superconductivity. The
polaron concept has been extended to several systems where one or many fermions
interact with a bath of bosons, e. g., small polaron, piezopolaron, polaronic
exciton, spin - or magnetic - polaron, "ripplonic polaron", "plasmaron",
"hydrated polarons" etc.

</DOC>
<DOC>
<DOCNO> 118908 </DOCNO>
Galaxy Cluster Baryon Fractions, Cluster Surveys and Cosmology


  The properties of nearby galaxy clusters limit the range of cosmological
parameters consistent with our universe. We describe the limits which arise
from studies of the intracluster medium (ICM) mass fraction fICM and
consideration of the possible sources of systematic error:
Omega_M<0.44h_{50}^{-1/2} at 95% confidence. We emphasize that independent of
Type Ia supernovae (SNe Ia) observations, this cluster study, taken together
with published cosmic microwave background (CMB) anisotropy studies, indicates
a non-zero quintessence or dark energy component Omega_Q>0.
 We then discuss future galaxy cluster surveys which will probe the abundance
of galaxy clusters to intermediate and high redshift. We investigate the
sensitivity of these surveys to the cosmological density parameter Omega_M and
the equation of state parameter w of any quintessence component. In particular,
we show that cluster survey constraints from a proposed large solid angle X-ray
survey are comparable in precision and complementary in nature to constraints
expected from future CMB anisotropy and SNe Ia studies.

</DOC>
<DOC>
<DOCNO> 67829 </DOCNO>
On the structure of large N cancellations in baryon chiral perturbation


  We show how to compute loop graphs in heavy baryon chiral perturbation theory
including the full functional dependence on the ratio of the Delta--nucleon
mass difference to the pion mass, while at the same time automatically
incorporating the 1/N cancellations that follow from the large-N spin-flavor
symmetry of baryons in QCD. The one-loop renormalization of the baryon axial
vector current is studied to demonstrate the procedure. A new cancellation is
identified in the one-loop contribution to the baryon axial vector current. We
show that loop corrections to the axial vector currents are exceptionally
sensitive to deviations of the ratios of baryon-pion axial couplings from SU(6)
values.

</DOC>
<DOC>
<DOCNO> 151483 </DOCNO>
Cubic couplings in D=6 N=4b supergravity on AdS_3\times S^3


  We determine the AdS exchange diagrams needed for the computation of 4--point
functions of chiral primary operators in the SCFT_2 dual to the D=6 N=4b
supergravity on the AdS_3\times S^3 background and compute the corresponding
cubic couplings. We also address the issue of consistent truncation.

</DOC>
<DOC>
<DOCNO> 10018 </DOCNO>
Crowd-anticrowd theory of the Minority Game


  The Minority Game is a simple yet highly non-trivial agent-based model for a
complex adaptive system. Despite its importance, a quantitative explanation of
the game's fluctuations which applies over the entire parameter range of
interest has so far been lacking. We provide such a quantitative description
based on the interplay between crowds of like-minded agents and their
anti-correlated partners (anticrowds).

</DOC>
<DOC>
<DOCNO> 85649 </DOCNO>
2D black holes and effective actions


  We compare the canonical quantization and the effective action method to
derive expectation values of the stress energy tensor for scalar fields
conformally coupled to a 2D Schwarzschild black hole spacetime. Disagreement of
the results may be reconduced to the incomplete knowledge of the effective
action. Appropriate ``phenomenological'' modification of this latter may
reconcile the two procedures.

</DOC>
<DOC>
<DOCNO> 99508 </DOCNO>
Fast Turbulent Reconnection


  Reconnection is the process by which magnetic fields in a conducting fluid
change their topology. This process is essential for understanding a wide
variety of astrophysical processes, including stellar and galactic dynamos and
astrophysical turbulence. To account for solar flares, solar cycles and the
structure of the galactic magnetic field reconnection must be fast, propagating
with a speed close to the Alfven speed. We show that the presence of a random
magnetic field component substantially enhances the reconnection rate and
enables fast reconnection, i.e. reconnection that does not depend on fluid
resistivity. The enhancement of the reconnection rate is achieved via a
combination of two effects. First of all, only small segments of magnetic field
lines are subject to direct Ohmic annihilation. Thus the fraction of magnetic
energy that goes directly into fluid heating goes to zero as fluid resistivity
vanishes. However, the most important enhancement comes from the fact that
unlike the laminar fluid case where reconnection is constrained to proceed line
by line, the presence of turbulence enables many magnetic field lines to enter
the reconnection zone simultaneously. A significant fraction of magnetic energy
goes into MHD turbulence and this enhances reconnection rates through an
increase in the field stochasticity. In this way magnetic reconnection becomes
fast when field stochasticity is accounted for. As a consequence solar and
galactic dynamos are also fast, i.e. do not depend on fluid resistivity.

</DOC>
<DOC>
<DOCNO> 151677 </DOCNO>
Noncommutative $\Phi^4$ Theory at Two Loops


  We study perturbative aspects of noncommutative field theories. This work is
arranged in two parts. First, we review noncommutative field theories in
general and discuss both canonical and path integral quantization methods. In
the second part, we consider the particular example of noncommutative $\Phi^4$
theory in four dimensions and work out the corresponding effective action and
discuss renormalizability of the theory, up to two loops.

</DOC>
<DOC>
<DOCNO> 102497 </DOCNO>
Noncommutative Geometry Year 2000


  We describe basic concepts of noncommutative geometry and a general
construction extending the familiar duality between ordinary spaces and
commutative algebras to a duality between Quotient spaces and Noncommutative
algebras. Basic tools of the theory, K-theory, Cyclic cohomology, Morita
equivalence, Operator theoretic index theorems, Hopf algebra symmetry are
reviewed. They cover the global aspects of noncommutative spaces, such as the
transformation $\theta \to 1/\theta$ for the NC torus $\Tb_{\theta}^2$, unseen
in perturbative expansions in $\theta$ such as star or Moyal products. We
discuss the foundational problem of "what is a manifold in NCG" and explain the
role of Poincare duality in K-homology which is the basic reason for the
spectral point of view. When specializing to 4-geometries this leads to the
universal "Instanton algebra". We describe our work with G. Landi which gives
NC-spheres $S_{\theta}^4$ from representations of the Instanton algebra. We
show that any compact Riemannian spin manifold whose isometry group has rank $r
\geq 2$ admits isospectral deformations to noncommutative geometries. We give a
survey of our work with H. Moscovici on the transverse geometry of foliations
which yields a diffeomorphism invariant geometry on the bundle of metrics on a
manifold and a natural extension of cyclic cohomology to Hopf algebras. Then,
our work with D. Kreimer on renormalization and the Riemann-Hilbert problem.
Finally we describe the spectral realization of zeros of zeta and L-functions
from the noncommutative space of Adele classes on a global field and its
relation with the Arthur-Selberg trace formula in the Langlands program. We end
with a tentalizing connection between the renormalization group and the missing
Galois theory at Archimedian places.

</DOC>
<DOC>
<DOCNO> 8076 </DOCNO>
Compaction of Rods: Relaxation and Ordering in Vibrated, Anisotropic


  We report on experiments to measure the temporal and spatial evolution of
packing arrangements of anisotropic, cylindrical granular material, using
high-resolution capacitive monitoring. In these experiments, the particle
configurations start from an initially disordered, low-packing-fraction state
and under vertical vibrations evolve to a dense, highly ordered, nematic state
in which the long particle axes align with the vertical tube walls. We find
that the orientational ordering process is reflected in a characteristic, steep
rise in the local packing fraction. At any given height inside the packing, the
ordering is initiated at the container walls and proceeds inward. We explore
the evolution of the local as well as the height-averaged packing fraction as a
function of vibration parameters and compare our results to relaxation
experiments conducted on spherically shaped granular materials.

</DOC>
<DOC>
<DOCNO> 150963 </DOCNO>
Radiation from SU(3) monopole scattering


  The energy radiated during the scattering of SU(3) monopoles is estimated as
a function of their asymptotic velocity v. In a typical scattering process the
total energy radiated is of order v^3 as opposed to v^5 for SU(2) monopoles.
For charge (1,1) monopoles the dipole radiation produced is estimated for all
geodesics on the moduli space. For charge (2,1) monopoles the dipole radiation
is estimated for the axially symmetric geodesic. The power radiated appears to
diverge in the massless limit. The implications of this for the case of
non-Abelian unbroken symmetry are discussed.

</DOC>
<DOC>
<DOCNO> 11122 </DOCNO>
Quantum Confinement Transition in a d-wave Superconductor


  We study the nature of the zero-temperature phase transition between a d-wave
superconductor and a Mott insulator in two dimensions. In this ``quantum
confinement transition'', spin and charge are confined to form the electron in
the Mott insulator. Within a dual formulation, direct transitions from d-wave
superconductors at half-filling to insulators with spin-Peierls (as well as
other) order emerge naturally. The possibility of striped superconductors is
also discussed within the dual formulation. The transition is described by
nodal fermions and bosonic vortices, interacting via a long-ranged statistical
interaction modeled by two, coupled Chern-Simons gauge fields, and the critical
properties of this model are discussed.

</DOC>
<DOC>
<DOCNO> 9208 </DOCNO>
Metastable states in disordered Ising magnets in mean-field


  The mechanism of appearance of exponentially large number of metastable
states in magnetic phases of disordered Ising magnets with short-range random
exchange is suggested. It is based on the assumption that transitions into
inhomogeneous magnetic phases results from the condensation of macroscopically
large number of sparse delocalized modes near the localization threshold. The
properties of metastable states in random magnets with zero ground state
magnetization (dilute antiferromagnet, binary spin glass, dilute ferromagnet
with dipole interaction) has been obtained in framework of this mechanism using
variant of mean-field approximation. The relations between the characteristics
of slow nonequilibrium processes in magnetic phases and thermodynamic
parameters of metastable states are established.

</DOC>
<DOC>
<DOCNO> 119882 </DOCNO>
Linear dynamics of the solar convection zone: excitation of waves in


  In this paper we report on the nonresonant conversion of convectively
unstable linear gravity modes into acoustic oscillation modes in shear flows.
The convectively unstable linear gravity modes can excite acoustic modes with
similar wave-numbers. The frequencies of the excited oscillations may be
qualitatively higher than the temporal variation scales of the source flow,
while the frequency spectra of the generated oscillations should be
intrinsically correlated to the velocity field of the source flow. We
anticipate that this nonresonant phenomenon can significantly contribute to the
production of sound waves in the solar convection zone.

</DOC>
<DOC>
<DOCNO> 120015 </DOCNO>
The Earliest Luminous Sources and the Damping Wing of the Gunn-Peterson


  Recent observations of high-redshift galaxies and quasars indicate that the
hydrogen component of the intergalactic medium (IGM) must have been reionized
at some redshift z>6. Prior to complete reionization, sources of ultraviolet
radiation will be seen behind intervening gas that is still neutral, and their
spectra should show the red damping wing of the Gunn-Peterson trough. While
this characteristic feature may, in principle, totally suppress the
Lyman-alphaa emission line in the spectra of the first generation of objects in
the universe, we show here that the IGM in the vicinity of luminous quasars
will be highly photoionized on several Mpc scales due to the source emission of
Lyman-continuum photons. If the quasar lifetime is shorter than the expansion
and gas recombination timescales, the volume ionized will be proportional to
the total number of photons produced above 13.6 eV: the effect of this local
photoionization is to greatly reduce the scattering opacity between the
redshift of the quasar and the boundary of its HII region. We find that the
transmission on the red side of the Lyman-alpha resonance is always greater
than 50% for sources radiating a total of 1e69.5 ionizing photons into the IGM.
The detection of a strong Lyman-alpha emission line in the spectra of bright
QSOs shining for >1e7 yr cannot then be used, by itself, as a constraint on the
reionization epoch. The first signs of an object radiating prior to the
transition from a neutral to an ionized universe may be best searched for in
the spectra of luminous sources with a small escape fraction of Lyman-continuum
photons into the IGM, or sources with a short duty cycle.

</DOC>
<DOC>
<DOCNO> 11173 </DOCNO>
Nonlinear interaction of charged particles with a free electron gas


  A nonlinear description of the interaction of charged particles penetrating a
solid has become of basic importance in the interpretation of a variety of
physical phenomena. Here we develop a many-body theoretical approach to the
quadratic decay rate, energy loss, and wake potential of charged particles
moving in an interacting free electron gas. Explicit expressions for these
quantities are obtained either within the random-phase approximation (RPA) or
with full inclusion of short-range exchange and correlation effects. The Z^3
correction to the energy loss of ions is evaluated beyond RPA, in the limit of
low velocities.

</DOC>
<DOC>
<DOCNO> 100493 </DOCNO>
RTT presentation of finite W-algebras


  We construct a wide class of finite W-algebras as truncations of Yangians.
These truncations correspond to algebra homomorphisms and allow to construct
the W-algebras as exchange algebras, the R-matrix being the Yangian's one.
  As an application, we classify all irreducible finite dimensionnal
representations of these W-algebras and determine their center.

</DOC>
<DOC>
<DOCNO> 12629 </DOCNO>
Accurate Results from Perturbation Theory for Strongly Frustrated


  We investigate the use of perturbation theory in finite sized frustrated spin
systems by calculating the effect of quantum fluctuations on coherent states
derived from the classical ground state. We first calculate the ground and
first excited state wavefunctions as a function of applied field for a 12-site
system and compare with the results of exact diagonalization. We then apply the
technique to a 20-site system with the same three fold site coordination as the
12-site system. Frustration results in asymptotically convergent series for
both systems which are summed with Pad\'e approximants.
  We find that at zero magnetic field the different connectivity of the two
systems leads to a triplet first excited state in the 12-site system and a
singlet first excited state in the 20-site system, while the ground state is a
singlet for both. We also show how the analytic structure of the Pad\'e
approximants at $|\lambda| \simeq 1$ evolves in the complex $\lambda$ plane at
the values of the applied field where the ground state switches between spin
sectors and how this is connected with the non-trivial dependence of the
$<S^{z}>$ number on the strength of quantum fluctuations. We discuss the origin
of this difference in the energy spectra and in the analytic structures. We
also characterize the ground and first excited states according to the values
of the various spin correlation functions.

</DOC>
<DOC>
<DOCNO> 7772 </DOCNO>
Infrared and Raman spectra of LiV2O5 single crystals


  The phonon dynamics of LiV2O5 single crystals is studied using infrared and
Raman spectroscopy techniques. The infrared-active phonon frequencies and
dielectric constants are obtained by oscillator fitting procedure of the
reflectivity data measured at room temperature. The Raman scattering spectra
are measured at room temperature and at T=10 K in all nonequivalent polarized
configurations. The assignment of the phonons is done by comparing the infrared
and Raman spectra of LiV2O5 and NaV2O5. The factor-group-analysis of the LiV2O5
crystal symmetry and of its constituent layers is performed to explain the
symmetry properties of the observed modes. We concluded that layer symmetry
dominates in the vibrational properties of this compound.

</DOC>
<DOC>
<DOCNO> 101443 </DOCNO>
Coupling Tensors and Poisson Geometry Near a Single Symplectic Leaf


  In the framework of the connection theory, a contravariant analog of the
Sternberg coupling procedure is developed for studying a natural class of
Poisson structures on fiber bundles, called coupling tensors. We show that
every Poisson structure near a closed symplectic leaf can be realized as a
coupling tensor. Our main result is a geometric criterion for the neighborhood
equivalence between Poisson structures over the same leaf. This criterion gives
a Poisson analog of the relative Darboux theorem due to Weinstein. Within the
category of the algebroids, coupling tensors are introduced on the dual of the
isotropy of a transitive Lie algebroid over a symplectic base. As a basic
application of these results, we show that there is a well defined notion of a
``linearized'' Poisson structure over a symplectic leaf which gives rise to a
natural model for the linearization problem.

</DOC>
<DOC>
<DOCNO> 101452 </DOCNO>
A Homeomorphism Invariant for Substitution Tiling Spaces


  We derive a homeomorphism invariant for those tiling spaces which are made by
rather general substitution rules on polygonal tiles, including those tilings,
like the pinwheel, which contain tiles in infinitely many orientations. The
invariant is a quotient of Cech cohomology, is easily computed directly from
the substitution rule, and distinguishes many examples, including most
pinwheel-like tiling spaces. We also introduce a module structure on cohomology
which is very convenient as well as of intuitive value.

</DOC>
<DOC>
<DOCNO> 100953 </DOCNO>
Vertex operator algebras, generalized doubles and dual pairs


  Let V be a simple vertex operator algebra and G a finite automorphism group.
Then there is a natural right G-action on the set of all inequivalent
irreducible V-modules. Let S be a finite set of inequivalent irreducible
V-modules which is closed under the action of G. There is a finite dimensional
semisimple associative algebra A_{\alpha}(G,S) for a suitable 2-cocycle \alpha
naturally determined by the G-action on S such that A_{\alpha}(G,S) and the
vertex operator algebra V^G form a dual pair on the sum of V-modules in S in
the sense of Howe. In particular, every irreducible V-module is completely
reducible V^G-module.

</DOC>
<DOC>
<DOCNO> 121523 </DOCNO>
The Distribution of [OII] Equivalent Widths of LCRS Galaxies


  We present a simple functional form for the joint distribution of R-band
luminosity and [OII] 3727 emission-line equivalent widths of galaxies, and show
that this form is a good fit to the galaxies in the Las Campanas Redshift
Survey. We find a relationship between [OII] equivalent width W and R-band
luminosity L_R of the approximate form: <W> \approx (10 \AA)
(L_R/L_{R,*})^{-1/2}, where L_{R,*} is the characteristic luminosity in the
Schechter function. Because this joint distribution yields information about
the relationship between stellar mass in a galaxy and its recent star-formation
rate, it can be useful for testing theories of galaxy formation. Furthermore,
understanding this joint distribution locally will make it easier to interpret
the evolution of [OII] emission-line widths to higher redshifts.

</DOC>
<DOC>
<DOCNO> 122848 </DOCNO>
Physical Modelling of the Zodiacal Dust Cloud


  (abridged) This review is based on an extensive work done in collaboration
with N. Gorkavyi, J. Mather, and T. Taidakova, which aimed at the physical
modelling of the interplanetary dust (IPD) cloud in the Solar system, i.e.,
establishing a link between the observable characteristics of the zodiacal
cloud and the dynamical and physical properties of the parent minor bodies. Our
computational approach permits with modest computer resources to integrate the
trajectories of hundreds of particles and to effectively store up to
$10^{10-11}$ positions, which provides a high fidelity 3D distribution of the
dust. Our numerical codes account for the major dynamical effects that govern
the motion of IPD particles. We have demonstrated the efficacy of our codes by
performing the following analyses: (i) simulation of the distribution of
Centaurs (comets scattered in their journey from the Kuiper belt inward the
Solar system) and revealing the effects of the outer planets in producing
`cometary belts'; (ii) detailed inspection of a rich resonant structure found
in these belts, which predicts the existence of gaps similar to the Kirkwood
gaps in the main asteroid belt; (iii) a preliminary 3-D physical model of the
IPD cloud, which includes three dust components -- asteroidal, cometary, and
kuiperoidal -- and is consistent with the available data of Pioneers and
Voyagers dust detectors; (iv) modeling of the IPD cloud, which provides a
zodiacal light distribution in accord, to the order of 1%, with a subset of the
COBE/DIRBE observations; and (v) showing that the resonant structure in dusty
circumstellar disks of Vega and Epsilon Eridani is a signature of embedded
extrasolar planets. Further improvements of our modelling and their importance
for astronomy and cosmology are outlined.

</DOC>
<DOC>
<DOCNO> 117289 </DOCNO>
Recoil-Induced-Resonances in Nonlinear, Ground-State, Pump-Probe


  A theory of pump-probe spectroscopy is developed in which optical fields
drive two-photon Raman transitions between ground states of an ensemble of
three-level $\Lambda $ atoms. Effects related to the recoil the atoms undergo
as a result of their interactions with the fields are fully accounted for in
this theory. The linear absorption coefficient of a weak probe field in the
presence of two pump fields of arbitrary strength is calculated. For subrecoil
cooled atoms, the spectrum consists of eight absorption lines and eight
emission lines. In the limit that $\chi_{1}\ll \chi_{2}$, where $\chi_{1}$ and
$\chi_{2}$ are the Rabi frequencies of the two pump fields, one recovers the
absorption spectrum for a probe field interacting with an effective two-level
atom in the presence of a single pump field. However when $\chi_{1}\gtrsim
\chi_{2}$, new interference effects arise that allow one to selectively turn on
and off some of these recoil induced resonances.

</DOC>
<DOC>
<DOCNO> 119255 </DOCNO>
X-ray observations of supernova remnant G54.1+0.3: X-ray spectrum and


  We present in this paper analyses of the $ROSAT$ PSPC and $ASCA$ SIS and GIS
observations of the Crab-like supernova remnant (SNR) G54.1+0.3. Its spectrum
obtained by $ROSAT$ PSPC favors a power law model with a photon index of
-0.8$^{+0.8}_{-2.0}$, absorbed energy flux in 0.1-2.4 keV of 1.0$\times
10^{-12}$ erg cm$^{-2}$ s$^{-1}$, and absorption column density of
12.3$^{+8.0}_{-3.2}\times 10^{21}$ cm$^{-2}$. $ASCA$ SIS observation shows that
its spectrum can also be best fitted with power law model. The fitted
parameters are, photon index -1.9$^{+0.1}_{-0.2}$, absorbed energy flux in
0.7-2.1 keV 6.5$\times10^{-13}$ erg cm$^{-2}$ s$^{-1}$, and column density
17.9$^{+2.8}_{-2.5}\times 10^{21}$ cm$^{-2}$. The high absorption column
density indicates a distance similar to the radius of the galaxy. The 0.1-2.4
keV X-ray luminosity of G54.1+0.3 is 3.2$\times10^{33}$$d_{10}^2$ erg s$^{-1}$,
where $d_{10}$ is the distance in 10 kpc. With an image restoration method we
have obtained high spatial resolution X-ray image of the remnant, which clearly
shows an X-ray jet pointing to the northeast with a length about 40$\arcsec$
from the center of the nebula. Its X-ray luminosity in 0.1-2.4 keV is about
5.1$\times10^{32}$$d_{10}^2$ erg s$^{-1}$. The X-ray jet is consistent with the
radio extension to the northeast in both direction and position. We propose
that the X-ray jet is connected with the pulsar assumed to exist in the
remnant.

</DOC>
<DOC>
<DOCNO> 84196 </DOCNO>
One Proposal about the Nature during Our Time and Space


  It made that the new symmetric property, the binary law, existed newly in our
time and space at the thing except the symmetric property of the principle of
general relativity which is already known in this paper clear. The introduction
of this symmetric property will have made dealing with the position tensor of
us handy as much as the surprise.

</DOC>
<DOC>
<DOCNO> 71867 </DOCNO>
Point form relativistic quantum mechanics, antiparticles and exchange


  It is shown that the dynamical observables calculated with the point form
relativistic quantum mechanics incorporate effects of particle-antiparticle
creation from the vacuum by interactions. The electromagnetic observables
obtained with the point form impulse approximation include contributions from
the ``pair'' exchange currents that are associated with the interactions
between particles. This implies that the recently calculated nucleon
electromagnetic formfactors with the chiral constituent quark model
automatically take into account effects of ``pair'' exchange currents that are
associated with the Goldstone boson exchange between the constituent quarks as
well as with the confining interaction.

</DOC>
<DOC>
<DOCNO> 122804 </DOCNO>
Should Elliptical Galaxies Be Idealised as Collisionless Equilibria?


  This talk summarises several different lines of argument suggesting that one
should not expect cuspy nonaxisymmetric galaxies to exist as robust, long-lived
collisionless equilibria, i.e., that such objects should not be idealised as
time-independent solutions to the collisionless Boltzmann equation.

</DOC>
<DOC>
<DOCNO> 12384 </DOCNO>
On the robust thermodynamical structures against arbitrary entropy form


  We discuss that the thermodynamical Legendre transform structure can be
retained not only for the arbitrary entropic form but also for the arbitrary
form of the energy constraints by following the discussion of Plastino and
Plastino. The thermodynamic relation between the expectation values and the
conjugate Lagrange multipliers are seen to be universal. Furthermore, Gibbs'
fundamental equation is shown to be unaffected by the choice of the entropy and
the definition of the mean values due to the robustness of the Legendre
transform structure.

</DOC>
<DOC>
<DOCNO> 123191 </DOCNO>
Properties of the Chandra Sources in M81


  The Chandra X-ray Observatory obtained a 50-ks observation of the central
region of M81 using the ACIS-S in imaging mode. The global properties of the 97
x-ray sources detected in the inner 8.3x8.3 arcmin field of M81 are examined.
Roughly half the sources are concentrated within the central bulge. The
remainder are distributed throughout the disk with the brightest disk sources
lying preferentially along spiral arms. The average hardness ratios of both
bulge and disk sources are consistent with power law spectra of index Gamma~1.6
indicative of a population of x-ray binaries. A group of much softer sources
are also present. The background source-subtracted logN-logS distribution of
the disk follows a power law of index ~ -0.5 with no change in slope over three
decades in flux. The logN-logS distribution of the bulge follows a similar
shape but with a steeper slope above ~4.0e+37 ergs/s. There is unresolved x-ray
flux from the bulge with a radial profile similar to that of the bulge sources.
This unresolved flux is softer than the average of the bulge sources and
extrapolating the bulge logN-logS distribution towards weaker sources can only
account for 20% of the unresolved flux. No strong time variability was observed
for any source with the exception of one bright, soft source.

</DOC>
<DOC>
<DOCNO> 151920 </DOCNO>
One-Loop Corrected Thermodynamics of the Extremal and Non-Extremal


  We consider the one-loop corrected geometry and thermodynamics of a rotating
BTZ black hole by way of a dimensionally reduced dilaton model. The analysis
begins with a comprehensive study of the non-extremal solution after which two
different methods are invoked to study the extremal case. The first approach
considers the extremal limit of the non-extremal calculations, whereas the
second treatment is based on the following conjecture: extremal and
non-extremal black holes ae qualitatively distinct entities. We show that only
the latter method yields regularity and consistency at the one-loop level. This
is suggestive of a generalized third law of thermodynamics that forbids
continuous evolution from non-extremal to extremal black hole geometries.

</DOC>
<DOC>
<DOCNO> 120749 </DOCNO>
Antlia: an outskirt Local Group Galaxy


  Deep (I,V-I) and (I,B-I) color-magnitude diagrams (CMDs) of the Antlia dwarf
galaxy, based on Science Verification (SV) data collected with the FORS I
camera on the ESO Very Large Telescope (VLT) are presented.
  By adopting the new calibration of the Tip of the Red Giant Branch (TRGB)
provided by Salaris & Cassisi (1998) we estimated that the Antlia distance
modulus is (m-M)o=25.98 with an error of 0.10 mag.
  We suggest an improvement of the classical TRGB method based on infrared H
and K magnitudes of TRGB stars. Such a method should overcome the well-known
limit of the "classical" TRGB method when dealing with metal-rich stellar
populations.

</DOC>
<DOC>
<DOCNO> 13525 </DOCNO>
The Payne effect for particle-reinforced elastomers


  The study deals with the Payne effect (a substantial decrease in the storage
modulus of a particle-reinforced elastomer with an increase in the amplitude of
mechanical oscillations). The influence of temperature, concentration of filler
and amplitude and frequency of strains is analyzed on the mechanical response
of filled rubbery polymers. Constitutive equations are derived using the
concept of two interpenetrating networks: one comprises semiflexible polymeric
chains connected to temporary junctions, whereas the other is formed by
aggregated filler clusters. Adjustable parameters are found by fitting
experimental data for natural rubber, bromobutyl rubber and styrene-butadiene
rubber reinforced by carbon black and polymeric particles. The critical
concentration of particles is determined that characterizes transition from an
ensemble of disjoint clusters to the network of filler. The volume fraction of
filler corresponding to this transition is found to be close to theoretical
predictions based on the percolation theory, as well as to experimental data
for isolator-conductor transition.

</DOC>
<DOC>
<DOCNO> 120016 </DOCNO>
The Effect of Diffusion on Pulsations of Stars on the Upper Main


  Recent dramatic improvements in the modeling of abundance evolution due to
diffusion in A stars have been achieved with the help of monochromatic opacity
tables from the OPAL group. An important result in the context of stellar
pulsations is the substantial helium abundance shown to be left over in the
driving region of delta Scuti-type pulsations in chemically peculiar Am stars.
An accurate opacity profile in the entire stellar envelope including the full
effect of heavy elements is also now available for the first time.
  Pulsations are shown to be excluded for young Am stars but occur naturally
when these stars evolve off the ZAMS. The predicted variable metallic A stars
all lie towards the red edge of the instability strip, in qualitative agreement
with the observed variable delta Delphini and mild Am stars.
  Results show little direct excitation from iron-peak elements in A-type
stars. The main abundance effect is due to the settling of helium, along with a
marginal effect due to the enhancement of hydrogen.

</DOC>
<DOC>
<DOCNO> 8686 </DOCNO>
Nonadiabatic noncyclic geometric phase and ensemble average spectrum of


  We generalize Yang's theory from the U(1) gauge field to the non-Abelian
$U(1)\times SU(2)_{spin}$ gauge field. Based on this generalization and taking
into account the geometric Pancharatnam phase as well as an effective
Aharonov-Bohm (AB) phase in nonadiabatic noncyclic transport, we calculate the
ensemble average Fourier spectrum of the conductance in disordered mesoscopic
rings connected to two leads. Our theory can explain the experimental results
reported by Morpurgo {\sl et al.} [Phys. Rev. Lett. {\bf 80}, 1050 (1998)]
satisfactorily. In particular, we clarify that the experimentally observed
splitting, as well as some structure on the sides of the main peak in the
ensemble average Fourier spectrum, stem from the nonadiabatic noncyclic
Pancharatnam phase and the effective AB phase, both being dependent on
spin-orbit coupling.

</DOC>
<DOC>
<DOCNO> 14043 </DOCNO>
Magnetic catalysis of parity breaking in a massive Gross-Neveu model and


  In the framework of a (2+1)-dimensional P-even massive Gross-Neveu model, an
external magnetic field is shown to induce a parity breaking first order phase
transition. Possibility of applying the results obtained to description of
magnetic phase transitions in high-temperature superconductors is discussed.

</DOC>
<DOC>
<DOCNO> 68234 </DOCNO>
Opening up extra dimensions at ultra-large scales


  The standard picture of viable higher-dimensional theories is that extra
dimensions manifest themselves at short distances only, their effects being
negligible at scales larger than some critical value. We show that this is not
necessarily true in models with infinite extra dimensions. As an example, we
consider a five-dimensional scenario with three 3-branes in which gravity is
five-dimensional both at short {\it and} very long distance scales, with
conventional four-dimensional gravity operating at intermediate length scales.
A phenomenologically acceptable range of validity of four-dimensional gravity
extending from microscopic to cosmological scales is obtained without strong
fine-tuning of parameters.

</DOC>
<DOC>
<DOCNO> 8019 </DOCNO>
Skyrmion Strings and Anomalous Hall Effect in Double Exchange Systems


  We perform Monte Carlo simulations to obtain quantitative results for the
anomalous Hall resistance, R_A, observed in colossal magnetoresistance
manganites. R_A arises from the interaction between the spin magnetization and
topological defects via spin-orbit coupling. We study these defects and how
they are affected by the spin-orbit coupling within the framework of the double
exchange model. The obtained anomalous Hall resistance is, in sign, order of
magnitude and shape, in agreement with experimental data.

</DOC>
<DOC>
<DOCNO> 84634 </DOCNO>
Quantum cosmology of 5D non-compactified Kaluza-Klein theory


  We study the quantum cosmology of a five dimensional non-compactified
Kaluza-Klein theory where the 4D metric depends on the fifth coordinate,
$x^4\equiv l$. This model is effectively equivalent to a 4D non-minimally
coupled dilaton field in addition to matter generated on hypersurfaces
l=constant by the extra coordinate dependence in the four-dimensional metric.
We show that the Vilenkin wave function of the universe is more convenient for
this model as it predicts a new-born 4D universe on the $l\simeq0$ constant
hypersurface.

</DOC>
<DOC>
<DOCNO> 8379 </DOCNO>
Quantum Critical Dynamics of the Skyrmion Lattice


  Near to filling fraction $\nu=1$, the quantum Hall ferromagnet contains
multiple Skyrmion spin excitations. This multi-Skyrmion system has a
tremendously rich quantum-critical structure. This is simplified when Skyrmions
are pinned by disorder. We calculate the nuclear relaxation rate in this case
and compare the result with experiment. We discus how such measurements may be
used to further probe the quantum-critical structure of the multi-Skyrmion
system.

</DOC>
<DOC>
<DOCNO> 120258 </DOCNO>
X-ray emission from young stars in the Tucanae association


  We report on X-ray emission from members of the recently discovered Tucanae
association, a group of stars with youth signatures and similar space motion.
The Tucanae association is the nearest known region of recent star formation
(at 45 pc) far from molecular clouds. We have made use of the ROSAT Data
Archive, and searched for X-rays from Tucanae stars in both ROSAT All-Sky
Survey (RASS) and pointed observations. The RASS detection rate for the Tucanae
members is 59%. We compare the X-ray luminosity function of the Tucanae
association to that of other star forming regions and young star clusters. Both
the X-ray luminosity function and the strong variability observed in the X-ray
lightcurves suggest that the examined stars are young, on the order of 10-30
Myrs.

</DOC>
<DOC>
<DOCNO> 169744 </DOCNO>
Extended coherent states and modified perturbation theory


  An extended coherent state for describing a system of two interacting quanum
objects is considered. A modified perturbation theory based on using the
extended coherent states is formulated.

</DOC>
<DOC>
<DOCNO> 152277 </DOCNO>
A Note on Singular Black Holes


  We reconsider entropy of black holes which do not have finite area horizon.
It is suggested that some of them should have nonzero entropy from both
supergravity and string theory point of view. We also refine our arguments in
our previous papers for the existence of the microstates of the black hole.

</DOC>
<DOC>
<DOCNO> 10431 </DOCNO>
Clustering and fluidization in a one-dimensional granular system:


  We study a 1-D granular gas of point-like particles not subject to gravity
between two walls at temperatures T_left and T_right. The system exhibits two
distinct regimes, depending on the normalized temperature difference Delta =
(T_right - T_left)/(T_right + T_left): one completely fluidized and one in
which a cluster coexists with the fluidized gas. When Delta is above a certain
threshold, cluster formation is fully inhibited, obtaining a completely
fluidized state. The mechanism that produces these two phases is explained. In
the fluidized state the velocity distribution function exhibits peculiar
non-Gaussian features. For this state, comparison between integration of the
Boltzmann equation using the direct-simulation Monte Carlo method and results
stemming from microscopic Newtonian molecular dynamics gives good coincidence,
establishing that the non-Gaussian features observed do not arise from the
onset of correlations.

</DOC>
<DOC>
<DOCNO> 83263 </DOCNO>
Knowledge and common knowledge in a distributed environment


  Reasoning about knowledge seems to play a fundamental role in distributed
systems. Indeed, such reasoning is a central part of the informal intuitive
arguments used in the design of distributed protocols. Communication in a
distributed system can be viewed as the act of transforming the system's state
of knowledge. This paper presents a general framework for formalizing and
reasoning about knowledge in distributed systems. We argue that states of
knowledge of groups of processors are useful concepts for the design and
analysis of distributed protocols. In particular, distributed knowledge
corresponds to knowledge that is ``distributed'' among the members of the
group, while common knowledge corresponds to a fact being ``publicly known''.
The relationship between common knowledge and a variety of desirable actions in
a distributed system is illustrated. Furthermore, it is shown that, formally
speaking, in practical systems common knowledge cannot be attained. A number of
weaker variants of common knowledge that are attainable in many cases of
interest are introduced and investigated.

</DOC>
<DOC>
<DOCNO> 13712 </DOCNO>
Phase transitions and random matrices


  Phase transitions generically occur in random matrix models as the parameters
in the joint probability distribution of the random variables are varied. They
affect all main features of the theory and the interpretation of statistical
models . In this paper a brief review of phase transitions in invariant
ensembles is provided, with some comments to the singular values decomposition
in complex non-hermitian ensembles.

</DOC>
<DOC>
<DOCNO> 170552 </DOCNO>
Phase-space picture of resonance creation and avoided crossings


  Complex coordinate scaling (CCS) is used to calculate resonance eigenvalues
and eigenstates for a system consisting of an inverted Gaussian potential and a
monochromatic driving field. Floquet eigenvalues and Husimi distributions of
resonance eigenfunctions are calculated using two different versions of CCS.
The number of resonance states in this system increases as the strength of the
driving field is increased, indicating that this system might have increased
stability against ionization when the field strength is very high. We find that
the newly created resonance states are scarred on unstable periodic orbits of
the classical motion. The behavior of these periodic orbits as the field
strength is increased may explain why there are more resonance states at high
field strengths than at low field strengths. Close examination of an avoided
crossing between resonance states shows that this type of avoided crossing does
not delocalize the resonance states, although it may lead to interesting
effects at certain field strengths.

</DOC>
<DOC>
<DOCNO> 102474 </DOCNO>
Examples and counterexamples for Perles' conjecture


  The combinatorial structure of a d-dimensional simple convex polytope can be
reconstructed from its abstract graph [Blind & Mani 1987, Kalai 1988]. However,
no polynomial/efficient algorithm is known for this task, although a
polynomially checkable certificate for the correct reconstruction was found by
[Joswig, Kaibel & Koerner 2000]. A much stronger certificate would be given by
the following characterization of the facet subgraphs, conjectured by M.
Perles:
    ``The facet subgraphs of the graph of a simple d-polytope are exactly
      all the (d-1)-regular, connected, induced, non-separating subgraphs''
      [Perles 1970].
  We give examples for the validity of Perles conjecture: In particular, it
holds for the duals of cyclic polytopes, and for the duals of stacked
polytopes. On the other hand, we identify a topological obstruction that must
be present in any counterexample to Perles' conjecture; thus, starting with a
modification of ``Bing's house'', we construct explicit 4-dimensional
counterexamples.

</DOC>
<DOC>
<DOCNO> 170156 </DOCNO>
Quorum of observables for universal quantum estimation


  Any method for estimating the ensemble average of arbitrary operator
(observables or not, including the density matrix) relates the quantity of
interest to a complete set of observables, i.e. a quorum}. This corresponds to
an expansion on an irreducible set of operators in the Liouville space. We give
two general characterizations of these sets. All the known unbiased
reconstruction techniques, i.e. ``quantum tomographies'', can be described in
this framework. New operatorial resolutions are given that can be used to
implement novel reconstruction schemes.

</DOC>
<DOC>
<DOCNO> 84600 </DOCNO>
Excitation of Neutron Star Oscillations by an Orbiting Particle


  The excitation of neutron stars is expected to be an important source of
gravitational radiation. Of fundamental importance is then to investigate
mechanisms that trigger oscillations in neutron stars in order to characterize
the emitted radiation. We present results from a numerical study of the
even-parity gravitational radiation generated from a particle orbiting a
neutron star. We focus our investigation on those conditions on the orbital
parameters that favor the excitation of $w$-modes. We find that, for
astrophysically realistic conditions, there is practically no $w$-mode
contribution to the emitted radiation. Only for particles with
ultra-relativistic orbital speeds $\ge 0.9c$, the $w$-mode does significantly
contribute to the total emitted gravitational energy. We also stress the
importance of setting consistent initial configurations.

</DOC>
<DOC>
<DOCNO> 120515 </DOCNO>
Double lenses


  The analysis of the shear induced by a single cluster on the images of a
large number of background galaxies is all centered around the curl-free
character of a well-known vector field that can be derived from the data. Such
basic property breaks down when the source galaxies happen to be observed
through two clusters at different redshifts, partially aligned along the line
of sight. In this paper we address the study of double lenses and obtain five
main results. (i) First we generalize the procedure to extract the available
information, contained in the observed shear field, from the case of a single
lens to that of a double lens. (ii) Then we evaluate the possibility of
detecting the signature of double lensing given the known properties of the
distribution of clusters of galaxies. (iii) As a different astrophysical
application, we demonstrate how the method can be used to detect the presence
of a dark cluster that might happen to be partially aligned with a bright
cluster studied in terms of statistical lensing. (iv) In addition, we show that
the redshift distribution of the source galaxies, which in principle might also
contribute to break the curl-free character of the shear field, actually
produces systematic effects typically two orders of magnitude smaller than the
double lensing effects we are focusing on. (v) Remarkably, a discussion of
relevant contributions to the noise of the shear measurement has brought up an
intrinsic limitation of weak lensing analyses, since one specific contribution,
associated with the presence of a non-vanishing two-galaxy correlation
function, turns out not to decrease with the density of source galaxies (and
thus with the depth of the observations).

</DOC>
<DOC>
<DOCNO> 170258 </DOCNO>
"Quantum mysteries for anyone," or classical verities for everyone?


  Unarticulated, implicit hypotheses in Bell's analysis of Einstein, Podolsky
and Rosen (EPR) correlations are identified and examined. These relate to the
mathematical-analytical properties of random variables, the character of the
relevant sample spaces and physical interpretations. We shown that continuous
hidden variables are not precluded by Bell inequalities. Finally, we propose a
local realistic model of optical EPRB experiments and consider its
implications.

</DOC>
<DOC>
<DOCNO> 9702 </DOCNO>
Carrier concentrations in Bi_{2}Sr_{2-z}La_{z}CuO_{6+\delta} single


  We measured the thermopower S and the Hall coefficients R_H of
Bi_{2}Sr_{2-z}La_{z}CuO_{6+\delta} (BSLCO) single crystals in a wide doping
range, in an effort to identify the actual hole concentrations per Cu, p, in
this system. It is found that the "universal" relation between the
room-temperature thermopower and T_c does not hold in the BSLCO system.
Instead, comparison of the temperature-dependent R_H data with other cuprate
systems is used as a tool to identify the actual p value. To justify this
approach, we compare normalized R_H(T) data of BSLCO, La_{2-x}Sr_{x}CuO_{4}
(LSCO), YBa_{2}Cu_{3}O_{y}, and Tl_{2}Ba_{2}CuO_{6+\delta}, and demonstrate
that the R_H(T) data of the LSCO system can be used as a template for the
estimation of p. The resulting phase diagram of p vs T_c for BSLCO suggests
that T_c is anomalously suppressed in the underdoped samples, becoming zero at
around p ~ 0.10, while the optimum T_c is achieved at p ~ 0.16 as expected.

</DOC>
<DOC>
<DOCNO> 99337 </DOCNO>
Osterwalder-Schrader axioms - Wightman Axioms


  The mathematical axiom systems for quantum field theory grew out of Hilbert's
sixth problem, that of stating the problems of quantum theory in precise
mathematical terms. There have been several competing mathematical systems of
axioms, and here we shall deal with those of A.S. Wightman and of K.
Osterwalder and R. Schrader, stated in historical order. They are centered
around group symmetry, relative to unitary representations of Lie groups in
Hilbert space. We also mention how the Osterwalder--Schrader axioms have
influenced the theory of unitary representations of groups.

</DOC>
<DOC>
<DOCNO> 116977 </DOCNO>
Multiple Charge State Beam Acceleration at Atlas


  A test of the acceleration of multiple charge-state uranium beams was
performed at the ATLAS accelerator. A 238U+26 beam was accelerated in the ATLAS
PII linac to 286 MeV (~1.2 MeV/u) and stripped in a carbon foil located 0.5 m
from the entrance of the ATLAS Booster section. A 58Ni9+ 'guide' beam from the
tandem injector was used to tune the Booster for 238U+38. All charge states
from the stripping were injected into the booster and accelerated. Up to 94% of
the beam was accelerated through the Booster linac, with losses mostly in the
lower charge states. The measured beam properties of each charge state and a
comparison to numerical simulations are reported in this paper.

</DOC>
<DOC>
<DOCNO> 102503 </DOCNO>
Connexion de Gauss-Manin associ\'ee \`a la d\'eformationverselle de la


  One studies the system of differential equations satisfied by the
hyperelliptic integral associated to a vanishing cycle defined for the versal
deformation of the $A-\mu$ singularity. As an application, the estimates on the
multiplicity of zeros of the hyperelliptic integral are given as a linear
function of the degree of present polynomials.

</DOC>
<DOC>
<DOCNO> 121410 </DOCNO>
The origin of the HH7-11 outflow


  New, high-sensitivity interferometric CO J=2-1 observations of the HH 7-11
outflow show that despite previous doubts, this system is powered by the Class
I source SVS 13. The molecular outflow from SVS 13 is formed by a shell with a
large opening angle at the base, which is typical of outflows from Class I
sources, but it also contains an extremely-high-velocity jet composed of
``molecular bullets'', which is more typical of Class 0 outflows. This suggests
that SVS 13 could be a very young Class I, which still keeps some features of
the previous evolutionary stage. We briefly discuss the nature of some sources
in the SVS 13 vicinity which are emitters of cm-wave continuum, but have no
counterpart at mm wavelengths.

</DOC>
<DOC>
<DOCNO> 8940 </DOCNO>
Critical thermodynamics of the two-dimensional systems in five-loop


  The RG functions of the 2D n-vector \phi^4 model are calculated in the
five-loop approximation. Perturbative series for the \beta-function and
critical exponents are resummed by the Pade-Borel and Pade-Borel-Leroy
techniques, resummation procedures are optimized and an accuracy of the
numerical results is estimated. In the Ising case n = 1 as well as in the
others (n = 0, n = -1, n = 2, 3,...32) an account for the five-loop term is
found to shift the Wilson fixed point location only briefly, leaving it outside
the segment formed by the results of the corresponding lattice calculations;
even error bars of the RG and lattice estimates do not overlap in the most
cases studied. This is argued to reflect the influence of the singular
(non-analytical) contribution to the \beta-function that can not be found
perturbatively. The evaluation of the critical exponents for n = 1, n = 0 and n
= -1 in the five-loop approximation and comparison of the numbers obtained with
their known exact counterparts confirm the conclusion that non-analytical
contributions are visible in two dimensions. For the 2D Ising model, the
estimates \omega = 1.31(3) for the correction-to-scaling exponent is found that
is close to the value 4/3 resulting from the conformal invariance.

</DOC>
<DOC>
<DOCNO> 85362 </DOCNO>
Gravitational Collapse and Cosmological Constant


  We consider here the effects of a non-vanishing cosmological term on the
final fate of a spherical inhomogeneous collapsing dust cloud. It is shown that
depending on the nature of the initial data from which the collapse evolves,
and for a positive value of the cosmological constant, we can have a globally
regular evolution where a bounce develops within the cloud. We characterize
precisely the initial data causing such a bounce in terms of the initial
density and velocity profiles for the collapsing cloud. In the cases otherwise,
the result of collapse is either formation of a black hole or a naked
singularity resulting as the end state of collapse. We also show here that a
positive cosmological term can cover a part of the singularity spectrum which
is visible in the corresponding dust collapse models for the same initial data.

</DOC>
<DOC>
<DOCNO> 69630 </DOCNO>
Interaction of electric charges in (2+1)D magnetic dipole gas


  The interaction of electrically charged particles in a dilute gas of
point--like magnetic dipoles is studied. We show that the interaction potential
at small distances has a linear piece due to overlap of the dipole clouds
gathered near electric sources. At large distances the potential becomes of the
Coulomb type with non-perturbatively renormalized charge of the test particle.
The physical applications of these results are discussed.

</DOC>
<DOC>
<DOCNO> 122466 </DOCNO>
Heavy sterile neutrinos - what they can be and what they can't


  We review current astrophysical bounds on MeV sterile neutrinos, and then we
discuss why a sterile keV neutrino is a natural warm dark matter candidate.

</DOC>
<DOC>
<DOCNO> 120390 </DOCNO>
Flaring and warping of the Milky Way disk: not only in the gas


  This paper presents an investigation of the outer disk structure by using
data from a recent release of the 2 micron sky survey (2MASS).
 This 2MASS data show unambiguously that the stellar disk thickens with
increasing distance from the Sun. In one of the field (longitude l$=$240) there
is also strong evidence of an assymetry associated with the Galactic warp. This
flaring and warping of the stellar disk is very similar to the features
observed in the HI disk. The thickening of the stellar disk explains the drop
in density observed near the Galactic plane: stars located at lower
 Galactic latitudes are re-distributed to higher latitudes. It is no longer
necessary to introduce a disk cut-off to explain the drop in density. It is
also not clear how this flaring disk is distinct from the thick disk in the
outer disk region. At least, for lines of sight in the direction of the outer
disk, the thickening of the disk is sufficient to account for the excess in
star counts attributed by some models to the thick disk.

</DOC>
<DOC>
<DOCNO> 12223 </DOCNO>
Critical behavior of the thermoelectric transport properties in


  The scaling behavior of the thermoelectric transport properties in disordered
systems is studied in the energy region near the metal-insulator transition.
Using an energy-dependent conductivity $\sigma$ obtained experimentally, we
extend our linear-response-based transport calculations in the
three-dimensional Anderson model of localization. Taking a dynamical scaling
exponent $z$ in agreement with predictions from scaling theories, we show that
the temperature-dependent $\sigma$, the thermoelectric power $S$, the thermal
conductivity $K$ and the Lorenz number $L_0$ obey scaling.

</DOC>
<DOC>
<DOCNO> 71364 </DOCNO>
Status of Trimaximal Neutrino Mixing


  Trimaximal mixing is the mixing hypothesis with maximal symmetry. In
trimaximal mixing there remains a still worrying conflict between the large
values of $\Delta m^2$ preferred by the atmospheric fits (possibly supported by
the early K2K data) and reactor limits on $\nu_e$-mixing. However, the latest
solar results do seem to point to energy-independent (ie. `no-scale') solar
solutions, like the trimaximal solution.

</DOC>
<DOC>
<DOCNO> 150943 </DOCNO>
ADM Worldvolume Geometry


  We describe the dynamics of a relativistic extended object in terms of the
geometry of a configuration of constant time. This involves an adaptation of
the ADM formulation of canonical general relativity. We apply the formalism to
the hamiltonian formulation of a Dirac-Nambu-Goto relativistic extended object
in an arbitrary background spacetime.

</DOC>
<DOC>
<DOCNO> 8746 </DOCNO>
Computation of dendritic microstructures using a level set method


  We compute time-dependent solutions of the sharp-interface model of dendritic
solidification in two dimensions by using a level set method. The steady-state
results are in agreement with solvability theory. Solutions obtained from the
level set algorithm are compared with dendritic growth simulations performed
using a phase-field model and the two methods are found to give equivalent
results. Furthermore, we perform simulations with unequal diffusivities in the
solid and liquid phases and find reasonable agreement with the available
theory.

</DOC>
<DOC>
<DOCNO> 8042 </DOCNO>
Statistics and noise in a quantum measurement process


  The quantum measurement process by a single-electron transistor or a quantum
point contact coupled to a quantum bit is studied. We find a unified
description of the statistics of the monitored quantity, the current, in the
regime of strong measurement and expect this description to apply for a wide
class of quantum measurements. We derive the probability distributions for the
current and charge in different stages of the process. In the parameter regime
of the strong measurement the current develops a telegraph-noise behavior which
can be detected in the noise spectrum.

</DOC>
<DOC>
<DOCNO> 68669 </DOCNO>
Gravitational Decay Modes of the Standard Model Higgs Particle


  If the Einstein field equations are employed at the tree level, then the
decay of the standard model Higgs particle into two gravitons is shown to be
independent of the gravitational coupling strength G. The result follows from
the physical equivalence between the Higgs induced ``inertial mass'' and the
``gravitational mass'' of general relativity. If the Higgs mass lies well
between the mass of a bottom quark anti-quark pair and the mass of a top quark
anti-quark pair, then the Higgs decay into two gravitons will dominate both the
QED induced two photon decay and the QCD induced two jet decays.

</DOC>
<DOC>
<DOCNO> 151294 </DOCNO>
Canonical quantization of a particle near a black hole


  We discuss the quantization of a particle near an extreme Reissner-Nordstrom
black hole in the canonical formalism. This model appears to be described by a
Hamiltonian with no well-defined ground state. This problem can be circumvented
by a redefinition of the Hamiltonian due to de Alfaro, Fubini and Furlan (DFF).
We show that the Hamiltonian with no ground state corresponds to a gauge in
which there is an obstruction at the boundary of spacetime requiring a
modification of the quantization rules. The redefinition of the Hamiltonian a
la DFF corresponds to a different choice of gauge. The latter is a good gauge
leading to standard quantization rules. Thus, the DFF trick is a consequence of
a standard gauge-fixing procedure in the case of black hole scattering.

</DOC>
<DOC>
<DOCNO> 121843 </DOCNO>
Radio Halo and Relic Candidates from the Westerbork Northern Sky Survey


  We have undertaken a systematic search for diffuse radio halos and relics in
all of the Abell clusters that are visible in the Westerbork Northern Sky
Survey (WENSS). In this survey we found 18 candidates, 11 of which are already
known from the literature, and 7 for which we provide the first evidence of
diffuse radio emission. All the clusters in this sample show other evidence for
a recent or ongoing merger. We also investigate the correlation between cluster
X-ray luminosity and radio power of halos. We develop a very simple model for
merger shocks that reproduces the sense of this correlation, although it is
probably not as steep as the correlation in the data. We discuss the
implications of X-ray--radio correlations for future detections of radio halos.

</DOC>
<DOC>
<DOCNO> 117022 </DOCNO>
Equilibrium solutions of the shallow water equations


  A statistical method for calculating equilibrium solutions of the shallow
water equations, a model of essentially 2-d fluid flow with a free surface, is
described. The model contains a competing acoustic turbulent {\it direct}
energy cascade, and a 2-d turbulent {\it inverse} energy cascade. It is shown,
nonetheless that, just as in the corresponding theory of the inviscid Euler
equation, the infinite number of conserved quantities constrain the flow
sufficiently to produce nontrivial large-scale vortex structures which are
solutions to a set of explicitly derived coupled nonlinear partial differential
equations.

</DOC>
<DOC>
<DOCNO> 80597 </DOCNO>
Chiral Symmetry Breaking in Strongly Coupled 1+1 Dimensional Lattice


  We analyse - within the hamiltonian formalism with staggered fermions - the
patterns of chiral symmetry breaking for the strongly coupled Schwinger and
$U({\cal N}_c)$-color `t Hooft models with one and two flavor of fermions.
Using the correspondence between these strongly coupled gauge models and
antiferromagnetic spin chains, we provide a rather intuitive picture of their
ground states, elucidate their patterns of chiral symmetry breaking, and
compute the pertinent chiral condensates. Our analysis evidences an intriguing
relationship between the values of the lattice chiral condensates of the `t
Hooft and Schwinger models with one flavor of fermions.

</DOC>
<DOC>
<DOCNO> 7741 </DOCNO>
Quantum Phase Interference for Quantum Tunneling in Spin Systems


  The point-particle-like Hamiltonian of a biaxial spin particle with external
magnetic field along the hard axis is obtained in terms of the potential field
description of spin systems with exact spin-coordinate correspondence. The
Zeeman energy term turns out to be an effective gauge potential which leads to
a nonintegrable pha se of the Euclidean Feynman propagator.
  The phase interference between clockwise and anticlockwise under barrier
propagations is recognized explicitly as the Aharonov-Bohm effect. An
additional phase which is significant for quantum phase interference is
discovered with the quantum theory of spin systems besides the known phase
obtained with the semiclassical treatment of spin. We also show the energ y
dependence of the effect and obtain the tunneling splitting at excited states
with the help of periodic instantons.

</DOC>
<DOC>
<DOCNO> 100170 </DOCNO>
All two dimensional links are null homotopic


  We show that any number of disjointly embedded 2-spheres in 4-space can be
pulled apart by a link homotopy, ie, by a motion in which the 2-spheres stay
disjoint but are allowed to self-intersect.

</DOC>
<DOC>
<DOCNO> 84349 </DOCNO>
Spherically symmetric empty space and its dual in general relativity


  In the spirit of the Newtonian theory, we characterize spherically symmetric
empty space in general relativity in terms of energy density measured by a
static observer and convergence density experienced by null and timelike
congruences. It turns out that space surrounding a static particle is entirely
specified by vanishing of energy and null convergence density. The
electrograv-dual$^{1}$ to this condition would be vanishing of timelike and
null convergence density which gives the dual-vacuum solution representing a
Schwarzschild black hole with global monopole charge$^{2}$ or with cloud of
string dust$^{3}$. Here the duality$^{1}$ is defined by interchange of active
and passive electric parts of the Riemann curvature, which amounts to
interchange of the Ricci and Einstein tensors. This effective characterization
of stationary vacuum works for the Schwarzschild and NUT solutions. The most
remarkable feature of the effective characterization of empty space is that it
leads to new dual spaces and the method can also be applied to lower and higher
dimensions.

</DOC>
<DOC>
<DOCNO> 69096 </DOCNO>
Polarization of vacuum in the decays of neutral kaons


  It is considered the state of $K^0$ before the decay as that embedded into
the vacuum of $+ \bar K^0 - \bar K^0$. Since the state of $K^0_S$ has the
lifeitme $\tau_S$, and the state of $K^0_L$ has the lifeitme $\tau_L$, the
vacuum of $+ \bar K^0 - \bar K^0$ is polarized. Due to the polarization of the
vacuum, $2\tau_S/\tau_L$ of $K^0_S$ decay with the delay $\approx \tau_L$. Thus
CP-invariance holds true in the decays of neutral kaons.

</DOC>
<DOC>
<DOCNO> 122478 </DOCNO>
Cosmic Microwave Background in Closed Multiply Connected Universes


  We have investigated the cosmic microwave background (CMB) anisotropy in
closed multiply connected universes
 (flat and hyperbolic) with low matter density. We show that the COBE
constraints on these low matter density models with non-trivial topology are
less stringent since a large amount of CMB anisotropy on large angular scales
can be produced due to the decay of the gravitational potential at late time.

</DOC>
<DOC>
<DOCNO> 151125 </DOCNO>
AdS/CFT Correspondence, Critical Strings and Stochastic Quantization


  We show that dilaton beta-function equation in the brane-like sigma-model
(regarded as NSR analogue of string theory on $AdS_5\times{S^5}$) has the form
of stochastic Langevin equation with non-Markovian noise. The worldsheet cutoff
is identified with stochastic time and the $V_5$-operator plays the role of the
noise. We derive the Fokker-Planck equation associated with this stochastic
process and show that the Hamiltonian of the $AdS_5$ supergravity defines the
distribution satisfying this Fokker-Planck equation. This means that the
dynamical compactification of flat ten-dimensional space-time on
$AdS_5\times{S^5}$ occurs as a result of the non-Markovian stochastic process,
generated by the $V_5$-operator noise. This provides us with an insight into
relation between holography principle and the concept of stochastic
quantization from the point of view of critical string theory.

</DOC>
<DOC>
<DOCNO> 39703 </DOCNO>
Direct Observation of Longitudinally Polarised W Bosons


  The three different helicity states of W bosons, produced in the reaction
e+e- -> W+W- -> l nu q q~ are studied using leptonic and hadronic W decays at
sqrt{s}=183GeV and 189GeV. The W polarisation is also measured as a function of
the scattering angle between the W- and the direction of the e- beam. The
analysis demonstrates that W bosons are produced with all three helicities, the
longitudinal and the two transverse states. Combining the results from the two
center-of-mass energies and with leptonic and hadronic W decays, the fraction
of longitudinally polarised W bosons is measured to be 0.261 +/- 0.051(stat.)
+/- 0.016(syst.) in agreement with the expectation from the Standard Model.

</DOC>
<DOC>
<DOCNO> 119147 </DOCNO>
Preliminary design of a NIR prime focus corrector for the Galileo


  In this paper a preliminary design for a prime focus corrector to be mounted
at the Telescopio Nazionale Galileo (TNG) is presented. The telescope is
located on La Palma (Canary Islands) and has a primary mirror of 3.5 m with a
hyperbolic sag. Two optical designs have been considered in order to exploit
detectors with 1k x 1k and 2k x 2k pixels. Each design makes use of four
lenses, two of which are aspherical. The first lens diameters are,
respectively, of 140 mm and 320 mm for the two kind of detectors. For both
designs the telescope pupil is deliberately not re-imaged, and therefore it
will not be possible to insert a cold stop. For such a reason particular care
has been dedicated to the telescope thermal background study, in order to
optimise the baffling system. The optics is able to correct fields of 11' x 11'
and of 60'x60', depending on the design. It should be considered that the
particular geometry of the focal plane array mosaic does not permit a full
exploitation of the entire field, being based on a combination of four
detectors. The selected chips are HgCdTe manufactured by Rockwell, i.e. Hawaii
I in the 1k x 1k case and Hawaii II in the 2k x 2k case.

</DOC>
<DOC>
<DOCNO> 11496 </DOCNO>
Anomalous scaling in depinning transitions


  It is demonstrated that the renormalization group (RG) flows of depinning
transitions do not depend on whether the driving force or the system velocity
is kept constant. This allows for a comparison between RG results and
corresponding self-organized critical models. However, close to the critical
point, scaling functions cross over to forms that can have singular behavior
not seen in equilibrium thermal phase transitions. These can be different for
the constant force and constant velocity driving modes, leading to different
apparent critical exponents. This is illustrated by comparing extremal dynamics
for interface depinning with RG results, deriving the change in apparent
exponents. Thus care has to be exercised in such comparisons.

</DOC>
<DOC>
<DOCNO> 85527 </DOCNO>
Elimination of Clock Jitter Noise in Spaceborn Laser Interferometers


  Space gravitational wave detectors employing laser interferometry between
free-flying spacecraft differ in many ways from their laboratory counterparts.
Among these differences is the fact that, in space, the end-masses will be
moving relative to each other. This creates a problem by inducing a Doppler
shift between the incoming and outgoing frequencies. The resulting beat
frequency is so high that its phase cannot be read to sufficient accuracy when
referenced to state-of-the-art space-qualified clocks. This is the problem that
is addressed in this paper. We introduce a set of time-domain algorithms in
which the effects of clock jitter are exactly canceled. The method employs the
two-color laser approach that has been previously proposed, but avoids the
singularities that arise in the previous frequency-domain algorithms. In
addition, several practical aspects of the laser and clock noise cancellation
schemes are addressed.

</DOC>
<DOC>
<DOCNO> 120766 </DOCNO>
Modelling the spectral energy distribution of galaxies. I. Radiation


  We describe a new tool for the analysis of the UV to the sub-millimeter
(sub-mm) spectral energy distribution (SED) of spiral galaxies. We use a
consistent treatment of grain heating and emission, solve the radiation
transfer problem for a finite disk and bulge, and self-consistently calculate
the stochastic heating of grains placed in the resulting radiation field.
 We use this tool to analyse the well-studied nearby edge-on spiral galaxy
NGC891. First we investigate whether the old stellar population in NGC891,
along with a reasonable assumption about the young stellar population, can
account for the heating of the dust and the observed far-infrared (FIR) and
sub-mm emission. The dust distribution is taken from the model of Xilouris et
al. (1999), who used only optical and near-IR observations to determine it. We
have found that such a simple model cannot reproduce the SED of NGC891,
especially in the sub-mm range. It underestimates by a factor of 2-4 the
observed sub-mm flux.
 A number of possible explanations exist for the missing sub-mm flux. We
investigate a few of them and demonstrate that one can reproduce the observed
SED in the FIR and the sub-mm quite well, as well as the observed radial
profile at 850 microns. For the models calculated we give the relative
proportion of the dust radiation powered by the old and young stellar
populations as a function of FIR/sub-mm wavelength. In all models we find that
the dust is predominantly heated by the young stellar population.

</DOC>
<DOC>
<DOCNO> 170751 </DOCNO>
Coupled cavities for enhancing the cross-phase modulation in


  We propose an optical double-cavity resonator whose response to a signal is
similar to that of an Electromagnetically Induced Transparency (EIT) medium. A
combination of such a device with a four-level EIT medium can serve for
achieving large cross-Kerr modulation of a probe field by a signal field. This
would offer the possibility of building a quantum logic gate based on photonic
qubits. We discuss the technical requirements that are necessary for realizing
a probe-photon phase shift of Pi caused by a single-photon signal. The main
difficulty is the requirement of an ultra-low reflectivity beamsplitter and to
operate a sufficiently dense cool EIT medium in a cavity.

</DOC>
<DOC>
<DOCNO> 39905 </DOCNO>
Charged Higgs Mass Limits from the Charged Kaon and Tau to Kaon


  From an analysis of the current world averages of the charged kaon and tau to
kaon branching fractions, we derive, within the framework of type II Higgs
doublets models such as the Minimal Supersymmetric Extension of the Standard
Model, $\tan{\beta}/m_H < 0.21$ GeV$^{-1}$ at a 90% confidence limit.

</DOC>
<DOC>
<DOCNO> 101309 </DOCNO>
Differentiable and algebroid cohomology, van Est isomorphisms, and


  In the first section we discuss Morita invariance of differentiable/algebroid
cohomology.
  In the second section we present an extension of the van Est isomorphism to
groupoids. This immediately implies a version of Haefliger's conjecture for
differentiable cohomology.
  As a first application we clarify the connection between differentiable and
algebroid cohomology (proved in degree 1, and conjectured in degree 2 by
Weinstein-Xu).
  As a second application we extend van Est's argument for the integrability of
Lie algebras. Applied to Poisson manifolds, this immediately gives (a slight
improvement of) Hector-Dazord's integrability criterion.
  In the third section we describe the relevant characteristic classes of
representations, living in algebroid cohomology, as well as their relation to
the van Est map. This extends Evens-Lu-Weinstein's characteristic class
$\theta_{L}$ (hence, in particular, the modular class of Poisson manifolds),
and also the classical characteristic classes of flat vector bundles.
  In the last section we describe some applications to Poisson geometry (e.g.
we clarify the Morita invariance of Poisson cohomology, and of the modular
class).

</DOC>
<DOC>
<DOCNO> 101636 </DOCNO>
Why a Conjecture of Poincare Doesn't Work


  Poincare had conjectured that the fact that closed loops could be shrunk to
points on a surface topologically equivalent to the surface of a sphere can be
generalised to three (and more) dimensions. After nearly a century the
conjecture has remained unproven. We given arguments below to show that the
conjecture doesn't work in three dimensions.

</DOC>
<DOC>
<DOCNO> 39734 </DOCNO>
Measurement of Angular Distributions and R= sigma_L/sigma_T in


  Production and decay angular distributions were extracted from measurements
of exclusive electroproduction of the rho^0(770) meson over a range in the
virtual photon negative four-momentum squared 0.5< Q^2 <4 GeV^2 and the
photon-nucleon invariant mass range 3.8< W <6.5 GeV. The experiment was
performed with the HERMES spectrometer, using a longitudinally polarized
positron beam and a ^3He gas target internal to the HERA e^{+-} storage ring.
The event sample combines rho^0 mesons produced incoherently off individual
nucleons and coherently off the nucleus as a whole. The distributions in one
production angle and two angles describing the rho^0 -> pi+ pi- decay yielded
measurements of eight elements of the spin-density matrix, including one that
had not been measured before. The results are consistent with the dominance of
helicity-conserving amplitudes and natural parity exchange. The improved
precision achieved at 4< W <7 GeV, in combination with other data at W>7 GeV,
reveals evidence for an energy dependence in the ratio R of the longitudinal to
transverse cross sections at constant Q^2.

</DOC>
<DOC>
<DOCNO> 102841 </DOCNO>
On the k-Systems of a Simple Polytope


  A k-system of the graph G(P) of a simple polytope P is a set of induced
subgraphs of G(P) that shares certain properties with the set of subgraphs
induced by the k-faces of P.
  This new concept leads to polynomial-size certificates in terms of G(P) for
both the set of vertex sets of facets as well as for abstract objective
functions (AOF) in the sense of Kalai.
  Moreover, it is proved that an acyclic orientation yields an AOF if and only
if it induces a unique sink on every 2-face.

</DOC>
<DOC>
<DOCNO> 101340 </DOCNO>
An integer valued SU(3) Casson invariant


  We define an integer valued invariant of homology spheres using the methods
of SU(3) gauge theory and study its behavior under orientation reversal and
connected sum.

</DOC>
<DOC>
<DOCNO> 83313 </DOCNO>
Base Encryption: Dynamic algorithms, Keys, and Symbol Set


  All the current modern encryption algorithms utilize fixed symbols for
plaintext and cyphertext. What I mean by fixed is that there is a set and
limited number of symbols to represent the characters, numbers, and
punctuations. In addition, they are usually the same (the plaintext symbols
have the same and equivalent counterpart in the cyphertext symbols). Almost all
the encryption algorithms rely on a predefined keyspace and length for the
encryption/decription keys, and it is usually fixed (number of bits). In
addition, the algorithms used by the encryptions are static. There is a
predefined number of operatiors, and a predefined order (loops included) of
operations. The algorithm stays the same, and the plaintext and cyphertext
along with the key are churned through this cypherblock.
  Base Encryption does the opposite: It utilizes the novel concepts of base
conversion, symbol remapping, and dynamic algorithms (dynamic operators and
dynamic operations). Base Encryption solves the weakness in todays encryption
schemes, namely... Fixed symbols (base) Fixed keylengths Fixed algorithms
(fixed number of operations and operators)
  Unique features... Immune from plain-text-attacks. Immune from
brute-force-attacks. Can utilize throwaway algorithms (as opposed to throw away
keys). Plug-And-Play engine (other cyphers can be augmentated to it)

</DOC>
<DOC>
<DOCNO> 121990 </DOCNO>
The vertical structure and kinematics of HI in spiral galaxies


  We discuss the distribution and kinematics of neutral hydrogen in the halos
of spiral galaxies. We focus in particular on new results obtained for the
nearby Sc galaxy NGC 2403 which have revealed the presence of extended HI
emission (here referred to as the `beard') at anomalous velocities with respect
to the `cold' HI disk. Modeling shows that this component has a mass of about
1/10 of the total HI mass and is probably located in the halo region. Its
kinematics differs from that of the thin HI disk: it rotates more slowly and
shows radial inflow. The origin of this anomalous gas component is unknown. It
could be the result of a galactic fountain or of accretion of extragalactic
`primordial' gas.

</DOC>
<DOC>
<DOCNO> 99425 </DOCNO>
On a conjecture of Shokurov: Characterization of toric varieties


  We verify a special case of V. V. Shokurov's conjecture about
characterization of toric varieties. More precisely, let $(X,D=\sum d_iD_i)$ be
a three-dimensional log variety such that $K_X+D$ is numerically trivial and
$(X,D)$ has only purely log terminal singularities. In this situation we prove
the inequality \{center} $\sum d_i\le \rk\Weil(X)/(\operatorname{algebraic
equivalence}) +\dim(X)$. \{center} We describe such pairs for which the
equality holds and show that all of them are toric.

</DOC>
<DOC>
<DOCNO> 8247 </DOCNO>
Evidence of a structural anomaly at 14 K in polymerised CsC60


  We report the results of a high-resolution synchrotron X-ray powder
diffraction study of polymerised CsC$_{60}$ in the temperature range 4 to 40 K.
Its crystal structure is monoclinic (space group I2/m), isostructural with
RbC$_{60}$. Below 14 K, a spontaneous thermal contraction is observed along
both the polymer chain axis, $a$ and the interchain separation along [111],
$d_1$. This structural anomaly could trigger the occurrence of the spin-singlet
ground state, observed by NMR at the same temperature.

</DOC>
<DOC>
<DOCNO> 120303 </DOCNO>
The ATESP Radio Survey II. The Source Catalogue


  This paper is part of a series reporting the results of the Australia
Telescope ESO Slice Project (ATESP) radio survey obtained at 1400 MHz with the
Australia Telescope Compact Array (ATCA) over the region covered by the ESO
Slice Project (ESP) galaxy redshift survey. The survey consists of 16 radio
mosaics with ~8"x14" resolution and uniform sensitivity (1sigma noise level ~79
microJy) over the whole area of the ESP redshift survey (~26 sq. degrees at
decl. -40 degr). Here we present the catalogue derived from the ATESP survey.
We detected 2960 distinct radio sources down to a flux density limit of ~0.5
mJy (6sigma), 1402 being sub-mJy sources. We describe in detail the procedure
followed for the source extraction and parameterization. The internal accuracy
of the source parameters was tested with Monte Carlo simulations and possible
systematic effects (e.g. bandwidth smearing) have been quantified.

</DOC>
<DOC>
<DOCNO> 8734 </DOCNO>
Moment free energies for polydisperse systems


  A polydisperse system contains particles with at least one attribute $\sigma$
(such as particle size in colloids or chain length in polymers) which takes
values in a continuous range. It therefore has an infinite number of conserved
densities, described by a density {\em distribution} $\rho(\sigma)$. The free
energy depends on all details of $\rho(\sigma)$, making the analysis of phase
equilibria in such systems intractable. However, in many (especially
mean-field) models the {\em excess} free energy only depends on a finite number
of (generalized) moments of $\rho(\sigma)$; we call these models truncatable.
We show, for these models, how to derive approximate expressions for the {\em
total} free energy which only depend on such moment densities. Our treatment
unifies and explores in detail two recent separate proposals by the authors for
the construction of such moment free energies. We show that even though the
moment free energy only depends on a finite number of density variables, it
gives the same spinodals and critical points as the original free energy and
also correctly locates the onset of phase coexistence. Results from the moment
free energy for the coexistence of two or more phases occupying comparable
volumes are only approximate, but can be refined arbitrarily by retaining
additional moment densities. Applications to Flory-Huggins theory for
length-polydisperse homopolymers, and for chemically polydisperse copolymers,
show that the moment free energy approach is computationally robust and gives
new geometrical insights into the thermodynamics of polydispersity.

</DOC>
<DOC>
<DOCNO> 68828 </DOCNO>
Non-relativistic quantum electrodynamics for strong laser-atom


  A formulation of quantum electrodynamics is given that applies to atoms in a
strong laser field by perturbation theory in a non-relativistic regime. Dipole
approximation is assumed. The dual Dyson series, here discussed by referring it
to the Birkhoff theorem for singularly perturbed linear differential equations,
can be applied and a perturbation series obtained transforming the Hamiltonian
by a Pauli-Fierz transformation. But, if just few photons are present
high-order harmonics cannot be generated. So, it is proven that odd high-order
harmonics only appear when the laser field is intense and one can substitute
the creation and annihilation operators by the square root of the mean number
of photons taken to be huge, the field retaining its coherency property as
observed experimentally for harmonics. In this case, the Hamiltonian for
perturbation theory comes to the Kramers-Henneberger form. The theory has a
dipolar contribution when the free-electron quiver motion amplitude is larger
than the atomic radius. For a Coulomb potential one has that the outer electron
is periodically kicked, and so a prove is given that the same should happen to
Rydberg atoms in intense microwave fields. The distribution representing the
kicking has a Fourier series with just odd terms. Using a modified
Rayleigh-Schr\"odinger perturbation theory, it is shown that under the same
condition of validity of the quiver motion amplitude to atomic radius ratio,
the atomic wave function is only slightly modified by the laser field due to
the way the energy levels rearrange themselves. This gives a prove of
stabilization in the limit of laser frequency going to infinity. Then,
perturbation theory can be applied when the Keldysh parameter becomes smaller
with respect to the shifted distance between the energy levels of the atom.

</DOC>
<DOC>
<DOCNO> 9147 </DOCNO>
Fully quantum mechanical moment of inertia of a mesoscopic ideal Bose


  The superfluid fraction of an atomic cloud can be defined using the cloud's
response to a rotation of the external potential, i.e. the moment of inertia.
In this paper we derive analytical results for the moment of inertia of a small
number of non-interacting Bosons using the canonical ensemble. The required
symmetrized averages are obtained via a representation of the partition
function by permutation cycles. Our results are useful to discriminate purely
quantum statistical effects from interaction effects in studies of
superfluidity and phase transitions in finite samples.

</DOC>
<DOC>
<DOCNO> 119263 </DOCNO>
Cosmic Ray Rejection and Readout Efficiency for Large-Area Arrays


  We present an algorithm to optimally process uniformly sampled array image
data obtained with a nondestructive readout. The algorithm discards full wells,
removes cosmic ray (particle) hits and other glitches, and makes a nearly
optimum estimate of the signal on each pixel. The algorithm also compresses the
data. The computer requirements are modest, and the results are robust. The
results are shown and compared to results of Fowler sampled and processed data.
Non-ideal detector performance may require some additional code, but this is
not expected to cost much processing time. Known types of detector faults are
addressed.

</DOC>
<DOC>
<DOCNO> 8871 </DOCNO>
Localization-induced Griffiths phase of disordered Anderson lattices


  We demonstrate that local density of states fluctuations in disordered
Anderson lattice models universally lead to the emergence of non-Fermi liquid
(NFL) behavior. The NFL regime appears at moderate disorder (W = W_c) and is
characterized by power-law anomalies, e. g. C/T ~ 1/T^{(1-\alpha)}, where the
exponent \alpha varies continuously with disorder, as in other Griffiths
phases. This Griffiths phase is not associated with the proximity to any
magnetic ordering, but reflects the approach to a disorder-driven
metal-insulator transition (MIT). Remarkably, the MIT takes place only at much
larger disorder W_{MIT} ~ 12 W_c, resulting in an extraordinarily robust NFL
metallic phase.

</DOC>
<DOC>
<DOCNO> 117185 </DOCNO>
Ion-Hose Instability in Long Pulse Induction Accelerators


  The ion-hose (or fast-ion) instability sets limits on the allowable vacuum in
a long-pulse, high current accelerator. Beam-induced ionization of the
background gas leads to the formation of an ion channel which couples to the
transverse motion of the beam. The instability is studied analytically and
numerically for several ion frequency distributions. The effects of beam
envelope oscillations on the growth of the instability will be discussed. The
saturated non-linear growth of the instability is derived analytically and
numerically for two different ion frequency distributions.

</DOC>
<DOC>
<DOCNO> 102151 </DOCNO>
Lelong numbers with respect to regular plurisubharmonic weights


  Generalized Lelong numbers of plurisubharmonic functions with respect to
plurisubharmonic weights (due to Demailly) are specified for weights with
multicircled asymptotics. Explicit formulas for these values are obtained in
terms of the directional Lelong numbers of the functions and the Newton
diagrams of the weights. An extension of Demailly's approximation theorem is
proved as well.

</DOC>
<DOC>
<DOCNO> 100337 </DOCNO>
An Embedding theorem for abelian monoidal categories


  We show that, with some technical conditions, an abelian category can be
embedded into the category of bimodules over a ring. The case of semisimple
rigid monoidal categories is studied in more detail.

</DOC>
<DOC>
<DOCNO> 84458 </DOCNO>
Black hole pair creation in de Sitter space: a complete one-loop


  We present an exact one-loop calculation of the tunneling process in
Euclidean quantum gravity describing creation of black hole pairs in a de
Sitter universe. Such processes are mediated by $S^2\times S^2$ gravitational
instantons giving an imaginary contribution to the partition function. The
required energy is provided by the expansion of the universe. We utilize the
thermal properties of de Sitter space to describe the process as the decay of a
metastable thermal state. Within the Euclidean path integral approach to
gravity, we explicitly determine the spectra of the fluctuation operators,
exactly calculate the one-loop fluctuation determinants in the $\zeta$-function
regularization scheme, and check the agreement with the expected scaling
behaviour. Our results show a constant volume density of created black holes at
late times, and a very strong suppression of the nucleation rate for small
values of $\Lambda$.

</DOC>
<DOC>
<DOCNO> 102191 </DOCNO>
Description of Vorticity by Grassmann Variables and an Extension to


  In this paper, particle physics concepts are blended into a field theory for
macroscopic phenomena: Fluid mechanics is enhanced by anticommuting Grassmann
variables to describe vorticity, while an additional interaction for the
Grassmann variables leads to supersymmetric fluid mechanics.

</DOC>
<DOC>
<DOCNO> 67859 </DOCNO>
Signatures of Extra Dimensions at e-gamma and gamma-gamma Colliders


  We study the processes \gamma \e -> \gamma \e and \gamma \gamma -> \gamma
\gamma, in the context of the proposal for Weak Scale Quantum Gravity (WSQG)
with large extra dimensions. With an ultraviolet cutoff $M_S \sim 1$ TeV for
the effective gravity theory, the cross sections obtained for these processes
at the Next Linear Collider (NLC), with the \e \gamma an \gamma \gamma options,
deviate from the predictions of the Standard Model significantly. Our results
suggest that, for typical proposed NLC energies and luminosities, the
predictions of WSQG can be tested in the range 1 TeV \lsim M_S \lsim 10 TeV,
making \e \gamma an \gamma \gamma colliders important tools for probing WSQG.

</DOC>
<DOC>
<DOCNO> 11757 </DOCNO>
Thermodynamics of non-abelian exclusion statistics


  The thermodynamic potential of ideal gases described by the simplest
non-abelian statistics is investigated. I show that the potential is the linear
function of the element of the abelian-part statistics matrix. Thus, the
factorizable property in the Haldane (abelian) fractional exclusion shown by
the author [W. H. Huang, Phys. Rev. Lett. 81, 2392 (1998)] is now extended to
the non-abelian case. The complete expansion of the thermodynamic potential is
also given.

</DOC>
<DOC>
<DOCNO> 70711 </DOCNO>
The Cosmological Constant and Warped Extra Dimensions


  We study the behavior of a general gravitational action, including quadratic
terms in the curvature, supplemented by a compact scalar field in 4+1
dimensions. The generalized Einstein equation for this system admits solutions
which are compact in one direction and Poincare invariant in the remaining
directions. These solutions do not require any fine-tuning of the parameters in
the action---including the cosmological constant---only that they should
satisfy some mild inequalities. Some of these inequalities can be expressed in
a universal form that does not depend on the number of extra compact dimensions
when the scenario is generalized beyond 4+1 dimensions.

</DOC>
<DOC>
<DOCNO> 120564 </DOCNO>
The Relative Age of the Thin and Thick Galactic Disks


  We determine the relative ages of the open cluster NGC 188 and selected
Hipparcos field stars by isochrone fitting, and compare them to the age of the
thick disk globular cluster 47 Tuc. The best fit age for NGC 188 was determined
to be $6.5 \pm 1.0$ Gyr. The solar metallicity Hipparcos field stars yielded a
slightly older thin disk age, $7.5 \pm 0.7$ Gyr. Two slightly metal-poor ($\feh
= -0.22$) field stars whose kinematic and orbital parameters indicate that they
are members of the thin disk were found to have an age of $9.7\pm 0.6$ Gyr. The
age for 47 Tuc was determined to be $12.5 \pm 1.5$ Gyr. All errors are internal
errors due to the uncertainty in the values of metallicity and reddening. Thus,
the oldest stars dated in the thin disk are found to be $2.8\pm 1.6$ Gyr
younger than 47 Tuc. Furthermore, as discussed by \citet{Chb99} 47 Tuc has a
similar age to three globular clusters located in the inner part of the
Galactic halo, implying that star formation in the thin disk started within
$2.8\pm 1.6$ Gyr of star formation in the halo.

</DOC>
<DOC>
<DOCNO> 69591 </DOCNO>
Exclusive semileptonic B decays to excited D mesons


  Exclusive semileptonic B decays to orbitally and radially excited charmed
mesons are investigated in the first order of the heavy quark expansion. The
emerging leading and subleading Isgur-Wise functions are calculated in the
framework of the relativistic quark model. It is found that both relativistic
and the 1/m_Q corrections play an important role and substantially modify
results. An interesting interplay between different corrections is observed.

</DOC>
<DOC>
<DOCNO> 101756 </DOCNO>
Grace-like polynomials


  Results of somewhat mysterious nature are known on the location of zeros of
certain polynomials associated with statistical mechanics (Lee-Yang circle
theorem) and also with graph counting. In an attempt at clarifying the
situation we introduce and discuss here a natural class of polynomials. Let
$P(z_1,...,z_m,w_1,...,w_n)$ be separately of degree 1 in each of its $m+n$
arguments. We say that $P$ is a Grace-like polynomial if $P(z_1,...,w_n)\ne0$
whenever there is a circle in ${\bf C}$ separating $z_1,...,z_m$ from
$w_1,...,w_n$. A number of properties and characterizations of these
polynomials are obtained.

</DOC>
<DOC>
<DOCNO> 10121 </DOCNO>
Dynamics of Br Electrosorption on Single-Crystal Ag(100): A


  We present dynamic Monte Carlo simulations of a lattice-gas model for bromine
electrodeposition on single-crystal silver (100). This system undergoes a
continuous phase transition between a disordered phase at low electrode
potentials and a commensurate c(2X2) phase at high potentials. The lattice-gas
parameters are determined by fitting simulated equilibrium adsorption isotherms
to chronocoulometric data, and free-energy barriers for adsorption/desorption
and lateral diffusion are estimated from ab initio data in the literature.
Cyclic voltammograms in the quasi-static limit are obtained by equilibrium
Monte Carlo simulations, while for nonzero potential scan rates we use dynamic
Monte Carlo simulation. The butterfly shapes of the simulated voltammograms are
in good agreement with experiments. Simulated potential-step experiments give
results for the time evolution of the Br coverage, as well as the c(2X2) order
parameter and its correlation length. During phase ordering following a
positive potential step, the system obeys dynamic scaling. The disordering
following a negative potential step is well described by random desorption with
diffusion. Both ordering and disordering processes are strongly influenced by
the ratio of the time scales for desorption and diffusion. Our results should
be testable by experiments, in particular cyclic voltammetry and surface X-ray
scattering.

</DOC>
<DOC>
<DOCNO> 121725 </DOCNO>
NICMOS Observations of Low-Redshift Quasar Host Galaxies


  We have obtained Near-Infrared Camera and Multi-Object Spectrometer images of
16 radio quiet quasars observed as part of a project to investigate the
``luminosity/host-mass limit.'' The limit results were presented in McLeod,
Rieke, & Storrie-Lombardi (1999). In this paper, we present the images
themselves, along with 1- and 2-dimensional analyses of the host galaxy
properties. We find that our model-independent 1D technique is reliable for use
on ground-based data at low redshifts; that many radio-quiet quasars live in
deVaucouleurs-law hosts, although some of the techniques used to determine host
type are questionable; that complex structure is found in many of the hosts,
but that there are some hosts that are very smooth and symmetric; and that the
nuclei radiate at ~2-20% of the Eddington rate based on the assumption that all
galaxies have central black holes with a constant mass fraction of 0.6%.
Despite targeting hard-to-resolve hosts, we have failed to find any that imply
super-Eddington accretion rates.

</DOC>
<DOC>
<DOCNO> 8918 </DOCNO>
First excited state calculation using different phonon bases for the


  The single-electron energy and static charge-lattice deformation correlations
have been calculated for the first excited state of a two-site Holstein model
within perturbative expansions using different standard phonon bases obtained
through Lang-Firsov (LF) transformation, LF with squeezed phonon states,
modified LF, modified LF transformation with squeezed phonon states, and also
within weak-coupling perturbation approach. Comparisons of the convergence of
the perturbative expansions for different phonon bases reveal that modified LF
approach works much better than other approaches for major range of the
coupling strength.

</DOC>
<DOC>
<DOCNO> 9287 </DOCNO>
Dimensional crossover in fragmentation


  Experiments in which thick clay plates and glass rods are fractured have
revealed different behavior of fragment mass distribution function in the small
and large fragment regions. In this paper we explain this behavior using
non-extensive Tsallis statistics and show how the crossover between the two
regions is caused by the change in the fragments' dimensionality during the
fracture process. We obtain a physical criterion for the position of this
crossover and an expression for the change in the power law exponent between
the small and large fragment regions. These predictions are in good agreement
with the experiments on thick clay plates

</DOC>
<DOC>
<DOCNO> 100820 </DOCNO>
Oblique projections and Schur complements


  Let H be a Hilbert space, L(H) the algebra of all bounded linear operators on
H and <, >_A : H \times H \to C the bounded sesquilinear form induced by a
selfadjoint A in L(H), < \xi, \eta >_A = < A \xi, \eta >, \xi, \eta in H. Given
T in L(H), T is A-selfadjoint if AT = T^*A. If S \subseteq H is a closed
subspace, we study the set of A-selfadjoint projections onto S,
  P(A, S) = {Q in L(H): Q^2 = Q, R(Q) = S, AQ = Q*A} for different choices of
A, mainly under the hypothesis that A\geq 0. There is a closed relationship
between the A-selfadjoint projections onto S and the shorted operator (also
called Schur complement) of A to S^\perp. Using this relation we find several
conditions which are equivalent to the fact that P(A, S) \neq \emptyset, in
particular in the case of A\geq 0 with A injective or with R(A) closed. If A is
itself a projection, we relate the set P(A, S) with the existence of a
projection with fixed kernel and range and we determine its norm.

</DOC>
<DOC>
<DOCNO> 70595 </DOCNO>
Resolving the Antibaryon-Production Puzzle in High-Energy Heavy-Ion


  We argue that the observed antiproton production in heavy-ion collisions at
CERN-SpS energies can be understood if (contrary to most sequential scattering
approaches) the backward direction in the process $p\bar p \leftrightarrow
\bar{n}\pi$ (with $\bar{n}$=5-6) is consistently accounted for within a thermal
framework. Employing the standard picture of subsequent chemical and thermal
freezeout, which induces an over-saturation of pion number with associated
chemical potentials of $\mu_\pi\simeq$~60-80 MeV, enhances the backward
reaction substantially. The resulting rates and corresponding cross sections
turn out to be large enough to maintain the abundance of antiprotons at
chemical freezeout until the decoupling temperature, in accord with the
measured $\bar{p}/p$ ratio in Pb(158AGeV)+Pb collisions.

</DOC>
<DOC>
<DOCNO> 117532 </DOCNO>
ISO Spectroscopy of Young Intermediate-Mass Stars in the BD+40 4124


  We present the results of ISO SWS and LWS grating scans towards the three
brightest members of the BD+40 4124 group in the infrared: BD+40 4124 (B2Ve),
LkHalpha 224 (A7e) and the embedded source LkHalpha 225. Emission from the pure
rotational lines of H_2, from ro-vibrational transitions of CO, from PAHs, from
H I recombination lines and from the infrared fine structure lines of [Fe II],
[Si II], [S I], [O I], [O III] and [C II] was detected. These emission lines
arise in the combination of a low-density (approx 10^2 cm^-3) H II region with
a clumpy PDR in the case of BD+40 4124. The lower transitions of the infrared H
I lines observed in BD+40 4124 are optically thick; most likely they arise in
either a dense wind or a circumstellar disk. This same region is also
responsible for the optical H I lines and the radio continuum emission. In the
lines of sight towards LkHalpha 224 and LkHalpha 225, the observed emission
lines arise in a non-dissociative shock produced by a slow (approx 20 km/s)
outflow arising from LkHalpha 225. Toward LkHalpha 225 we also observe a
dissociative shock, presumably located closer to the outflow source than the
non-dissociative shock. In the line of sight towards LkHalpha 225 we observed
absorption features due to solid water ice and amorphous silicates, and due to
gas-phase H_2O, CO and CO_2. No solid CO_2 was detected towards LkHalpha 225,
making this the first line of sight where the bulk of the CO_2 is in the
gas-phase.

</DOC>
<DOC>
<DOCNO> 84574 </DOCNO>
Sub-Microarcsecond Astrometry and New Horizons in Relativistic


  Attaining the limit of sub-microarcsecond optical resolution will completely
revolutionize fundamental astrometry by merging it with relativistic
gravitational physics. Beyond the sub-microarcsecond threshold, one will meet
in the sky a new population of physical phenomena caused by primordial
gravitational waves from early universe and/or different localized astronomical
sources, space-time topological defects, moving gravitational lenses, time
variability of gravitational fields of the solar system and binary stars, and
many others. Adequate physical interpretation of these yet undetectable
sub-microarcsecond phenomena can not be achieved on the ground of the
"standard" post-Newtonian approach (PNA), which is valid only in the near-zone
of astronomical objects having a time-dependent gravitational field. We
describe a new, post-Minkowskian relativistic approach for modeling astrometric
observations having sub-microarcsecond precision and briefly discuss the
light-propagation effects caused by gravitational waves and other phenomena
related to time-dependent gravitational fields. The domain of applicability of
the PNA in relativistic space astrometry is explicitly outlined.

</DOC>
<DOC>
<DOCNO> 9409 </DOCNO>
Optical dichroism in nanotubes


  Utilizing the line-group symmetry of single-wall nanotubes, we have assigned
their electron-energy bands by the symmetry-based quantum numbers. The
selection rules for optical absorption are presented in terms of these quantum
numbers. Different interband transitions become allowed as the polarization of
incident light is varied, and we predict a substantial optical dichroism. We
propose how to observe this effect in experiments on a single nanotube, and how
it can be used to control quantum transport in nanotubes to obtain information
about the structure.

</DOC>
<DOC>
<DOCNO> 120317 </DOCNO>
The Effect of Gas Loss on the Formation of Bound Stellar Clusters


  The effect of gas ejection on the structure and binding energy of newly
formed stellar clusters is investigated. The star formation efficiency (SFE),
necessary for forming a gravitationally bound stellar cluster, is determined.
  Two sets of numerical N-body simulations are presented: As a first simplified
approach we treat the residual gas as an external potential. The gas expulsion
is approximated by reducing the gas mass to zero on a given timescale, which is
treated as a free parameter. In a second set of simulations we use smoothed
particle hydrodynamics (SPH) to follow the dynamics of the outflowing residual
gas self-consistently. We investigate cases where gas outflow is induced by an
outwards propagating shock front and where the whole gas cloud is heated
homogeneously, leading to ejection.
  If the stars are in virial equilibrium with the gaseous environment
initially, bound clusters only form in regions where the local SFE is larger
than 50% or where the gas expulsion timescale is long compared to the dynamical
timescale. A small initial velocity dispersion of the stars leads to a
compaction of the cluster during the expulsion phase and reduces the SFE needed
to form bound clusters to less than 10%.

</DOC>
<DOC>
<DOCNO> 102819 </DOCNO>
Singularities and Poisson geometry of certain representation spaces


  Playing off against each other the real and complex structures, we elucidate
the local structure of certain representation spaces in the world of Poisson
geometry. Particular cases of these spaces arise as moduli spaces of semistable
holomorphic vector bundles on Riemann surfaces.

</DOC>
<DOC>
<DOCNO> 118293 </DOCNO>
Intrinsic and Cosmological Signatures in Gamma-Ray Burst Time Profiles:


  The time profiles of many gamma-ray bursts consist of distinct pulses, which
offers the possibility of characterizing the temporal structure of these bursts
using a relatively small set of pulse shape parameters. We have used a pulse
decomposition procedure to analyze the Time-to-Spill (TTS) data for all bursts
observed by BATSE up through trigger number 2000, in all energy channels for
which TTS data is available. We obtain amplitude, rise and decay timescales, a
pulse shape parameter, and the fluences of individual pulses in all of the
bursts. We investigate the correlations between brightness measures (amplitude
and fluence) and timescale measures (pulse width and separation) which may
result from cosmological time dilation of bursts, or from intrinsic properties
of burst sources or from selection effects. The effects of selection biases are
evaluated through simulations. The correlations between these parameters among
pulses within individual bursts give a measure of the intrinsic effects while
the correlations among bursts could result both from intrinsic and cosmological
effects. We find that timescales tend to be shorter in bursts with higher peak
fluxes, as expected from cosmological time dilation effects, but also find that
there are non-cosmological effects contributing to this inverse correlation. We
find that timescales tend to be longer in bursts with higher total fluences,
contrary to what is expected from cosmological effects. We also find that peak
fluxes and total fluences of bursts are uncorrelated, indicating that they
cannot both be good distance indicators for bursts.

</DOC>
<DOC>
<DOCNO> 170220 </DOCNO>
Quantum Message Disruption: A Two-State Model


  A game in which one player makes unitary transformations of a simple system,
and another seeks to confound the resulting state by a randomly chosen action
is analyzed carefully. It is shown that the second player can reduce any system
to a completely random one by rotation through an angle of 120 degrees, about
an axis chosen at random. If, on the other hand, the second player is forced to
behave ``classically'' by reducing the wave function, then the first play
retains an advantage, which the second player may eliminate by repeated
measurement using randomly selected bases.

</DOC>
<DOC>
<DOCNO> 100411 </DOCNO>
Harmonic spinors on homogeneous spaces


  Let G be a compact, semi-simple Lie group and H a maximal rank reductive
subgroup. The irreducible representations of G can be constructed as spaces of
harmonic spinors with respect to a Dirac operator on the homogeneous space G/H
twisted by bundles associated to the irreducible, possibly projective,
representations of H. Here, we give a quick proof of this result, computing the
index and kernel of this twisted Dirac operator using a homogeneous version of
the Weyl character formula noted by Gross, Kostant, Ramond, and Sternberg, as
well as recent work of Kostant regarding an algebraic version of this Dirac
operator.

</DOC>
<DOC>
<DOCNO> 72174 </DOCNO>
Models of inflation, supersymmetry breaking and observational


  We review the connection between inflationary models and observations and
concentrate to describe models based on softly broken supersymmetry, in
particular running mass models, and their predictions. We then present a fit of
the spectral index of the curvature perturbation, assuming a flat $\Lambda$CDM
cosmology.

</DOC>
<DOC>
<DOCNO> 10835 </DOCNO>
Energy spectra of fractional quantum Hall systems in the presence of a


  The energy spectrum of a two-dimensional electron gas (2DEG) in the
fractional quantum Hall regime interacting with an optically injected valence
band hole is studied as a function of the filling factor $\nu$ and the
separation $d$ between the electron and hole layers. The response of the 2DEG
to the hole changes abruptly at $d$ of the order of the magnetic length
$\lambda$. At $d<\lambda$, the hole binds electrons to form neutral ($X$) or
charged ($X^-$) excitons, and the photoluminescence (PL) spectrum probes the
lifetimes and binding energies of these states rather than the original
correlations of the 2DEG. The ``dressed exciton'' picture (in which the
interaction between an exciton and the 2DEG was proposed to merely enhance the
exciton mass) is questioned. Instead, the low energy states are explained in
terms of Laughlin correlations between the constituent fermions (electrons and
$X^-$'s) and the formation of two-component incompressible fluid states in the
electron--hole plasma. At $d>2\lambda$, the hole binds up to two Laughlin
quasielectrons (QE) of the 2DEG to form fractionally charged excitons
$h$QE$_n$. The previously found ``anyon exciton'' $h$QE$_3$ is shown to be
unstable at any value of $d$. The critical dependence of the stability of
different $h$QE$_n$ complexes on the presence of QE's in the 2DEG leads to the
observed discontinuity of the PL spectrum at $\nu={1\over3}$ or ${2\over3}$.

</DOC>
<DOC>
<DOCNO> 101570 </DOCNO>
D-Branes on Calabi-Yau Manifolds


  We give an overview of recent work on Dirichlet branes on Calabi-Yau
threefolds which makes contact with Kontsevich's homological mirror symmetry
proposal, proposes a new definition of stability which is appropriate in string
theory, and provides concrete quiver categories equivalent to certain
categories of branes on CY.
  To appear in the proceedings of the 3rd European Congress of Mathematics.

</DOC>
<DOC>
<DOCNO> 9055 </DOCNO>
XPS and NMR as Complementary Probes of Pseudogaps and Spin-charge


  The possibility that strongly correlated many-electron systems may exhibit
spin-charge separation has generated great excitement, particularly in the
light of recent experiments on low dimensional conductors and high temperature
superconductors. However, finding experimental support for this hypothesis has
been made difficult by the fact that most commonly used probes couple
simultaneously to spin and charge excitations. We argue that core hole
photoemission (XPS)/nuclear magnetic resonance (NMR) couple independently and
in exactly comparable ways to the local charge/spin susceptibilities of the
system being measured. The explicit comparison of XPS and NMR data,
particularly in systems which exhibit a pseudogap, may therefore yield fresh
evidence for the existence (or non-existence) of spin-charge separation.
Application of these ideas to the normal state of high temperature
superconductors is discussed, and the application is further illustrated in
some detail for quasi one-dimensional systems with charge density waves.

</DOC>
<DOC>
<DOCNO> 170776 </DOCNO>
Non-holonomic Quantum Devices


  We analyze the possibility and efficiency of non-holonomic control over
quantum devices with exponentially large number of Hilbert space dimensions. We
show that completely controllable devices of this type can be assembled from
elementary units of arbitrary physical nature, and can be employed efficiently
for universal quantum computations and simulation of quantum field dynamics.

</DOC>
<DOC>
<DOCNO> 12085 </DOCNO>
Phase-Sensitive Impurity Effects in Vortex Core of Moderately Clean


  We study impurity effects in vortex core of two-dimensional moderately clean
su perconductors within the quasiclassical theory. The impurity scattering rate
$\G amma(E)$ of the Andreev bound states in vortex core with +1 vorticity of
p-wav e superconductors with ${\mib d}=\hat{\mib z}(p_x+\iu p_y)$ is suppre
ssed, compared to the normal state scattering rate $\Gamma_{\rm n}$ in the
energ y region $\Gamma_{\rm n}^3/E_\delta^2\ll E\ll E_\delta\equiv
|\delta_0|\Delta_\i nfty$ with scattering phase shift $\delta_0$
$(|\delta_0|\ll 1)$ and the pair-po tential in bulk $\Delta_\infty$. Further we
find that $\Gamma(E)/\Gamma_{\rm n}$ for p-wave superconductors with ${\mib
d}=\hat{\mib z}(p_x-\iu p_y)$ is at most ${\cal O}(E/\Delta_\i nfty)$. These
results are in marked contrast to the even-parity case (s,d-wave), where
$\Gamma(E)/\Gamma_{\rm n}$ is known to be proportional to $\ln(\Delta_\i
nfty/E)$ . Parity- and chirality-dependences of impurity effects are attributed
to the Andr eev reflections involved in the impurity-induced scattering between
bound states . Implications for the flux flow conductivity is also discussed.
Novel enhanceme nt of flux flow conductivity is expected to occur at $T\ll
E_\delta$ for ${\mib d}=\hat{\mib z}(p_x+\iu p_y)$ and at $T\ll \Delta_\infty$
for ${\mib d}=\hat{\mib z}(p_x-\iu p_y)$.

</DOC>
<DOC>
<DOCNO> 118436 </DOCNO>
A few things we do not know about the sun and F stars and G stars


  WE do not know how to make realistic model atmospheres; understand
convection; consider the variation in microturbulent velocity; understand
spectroscopy; have good spectra of the sun or any other star; have energy
distributions for the sun or any other star; know how to determine abundances;
know the abundances of the sun or any other star; have good atomic and
molecular data; One half the lines in the solar spectrum are not identified. We
should get our own house in order before worrying about the neighbors.

</DOC>
<DOC>
<DOCNO> 80977 </DOCNO>
Cooling, Monopoles, and Vortices in SU(2) Lattice Gauge Theory


  We study monopoles and vortices in SU(2) lattice gauge theory on a 24**4
lattice at beta=2.50. We find a value of fundamental string tension from
monopoles in the maximum Abelian gauge consistent with the full SU(2) value.
Using direct and indirect center gauges, we find fundamental string tension
values from P-vortices which are larger than the full SU(2) result. After a
single cooling sweep, the string tensions from monopoles and P-vortices are all
30% lower than the full SU(2) value, while the U(1) string tension in the
maximum Abelian gauge remains consistent with the full SU(2) result. Blocking
the lattice after cooling does not restore the low values of string tension
found with monopoles and vortices.

</DOC>
<DOC>
<DOCNO> 151805 </DOCNO>
On the Origin of Mass in Field Theory


  The problem of mass origin in field theory lies in accounting for a quantum
field theory with massive vector bosons out of a classical field theory which
is both gauge invariant and massless. The possibility is here considered that,
instead of assuming the existence of Higgs bosons, the very process of
generating the correct action for the quantum theory allows for generation of
massive terms in the quantum Lagrangian. We show that this is possible provided
the gauge-averaging functional is viewed as a map acting on the potential and
taking values in the set of 4x4 matrices. Gauge independence is achieved upon
considering the joint effect of gauge-averaging term and ghost fields. As an
example, the modified photon and ghost propagators in quantum electrodynamics
are evaluated when a term proportional to contraction of flat-space
gamma-matrices with the potential is suitably added to the Lorenz term in the
choice of supplementary condition, and the associated perturbative
renormalization is outlined. The experience acquired with quantum
electrodynamics is used to find under which conditions correct masses of W and
Z bosons can be reproduced.

</DOC>
<DOC>
<DOCNO> 99958 </DOCNO>
Integrable models and star structures


  We consider the representations of Hopf algebras involved in some physical
models, namely, factorizable S-matrix models (FSM's), one-dimensional quantum
spin chains (QSC's) and statistical vertex models (SVM's). These physical
representations have definite hermiticity assignments and lead to star
structures on the corresponding Hopf algebras. It turns out that for FSM's and
the quantum mechanical time-evolution of QSC's the corresponding stars are
compatible with the Hopf structures. However, in the case of statistical models
the resulting star structure is not a Hopf one but what we call a twisted star.
Real representations of a twisted star Hopf algebra do not close under the
usual tensor product of representations. We briefly comment on the relation of
these results with the Wick rotation.

</DOC>
<DOC>
<DOCNO> 10187 </DOCNO>
Dielectric nonlinearity of relaxor ferroelectric ceramics at low ac


  Dielectric nonlinear response of
(PbMg$_{1/3}$Nb$_{2/3}$O$_3$)$_{0.9}$(PbTiO$_3$)$_{0.1}$ (0.9PMN-0.1PT) relaxor
ceramics was investigated under different ac drive voltages. It was observed
that: (i) the dielectric permittivity is independent on ac field amplitude at
high temperatures; (ii) with increasing ac drive, the permittivity maximum
increases, and the temperature of the maximum shifts to lower temperature;
(iii) the nonlinear effect is weakened when the measurement frequency
increases. The influences of increasing ac drive were found to be similar to
that of decreasing frequency. It is believed that the dielectric nonlinearities
of relaxors at low drives can be explained by the phase transition theory of
ergodic space shrinking in succession. A Monte Carlo simulation was performed
on the flips of micro polarizations at low ac drives to verify the theory.

</DOC>
<DOC>
<DOCNO> 69316 </DOCNO>
Harry Lehmann and the analyticity unitarity programme


  I try to describe the extremely fruitful interaction I had with Harry Lehmann
and the results which came out of the analyticity unitarity programme,
especially the proof of the Froissart bound, which, with recent and future
measurements of total cross-sections and real parts, remains topical.

</DOC>
<DOC>
<DOCNO> 9334 </DOCNO>
Adsorption on carbon nanotubes: quantum spin tubes, magnetization


  We formulate the problem of adsorption onto the surface of a carbon nanotube
as a lattice gas on a triangular lattice wrapped around a cylinder. This model
is equivalent to an XXZ Heisenberg quantum spin tube. The geometric frustration
due to wrapping leads generically to four magnetization plateaus, in contrast
to the two on a flat graphite sheet. We obtain analytical and numerical results
for the magnetizations and transition fields for armchair, zig-zag and chiral
nanotubes. The zig-zags are exceptional in that one of the plateaus has
extensive zero temperature entropy in the classical limit. Quantum effects lift
up the degeneracy, leaving gapless excitations which are described by a $c=1$
conformal field theory with compactification radius quantized by the tube
circumference.

</DOC>
<DOC>
<DOCNO> 40403 </DOCNO>
Report of the Higgs Working Group of the Tevatron Run 2 SUSY/Higgs


  This report presents the theoretical analysis relevant for Higgs physics at
the upgraded Tevatron collider and documents the Higgs Working Group
simulations to estimate the discovery reach in Run 2 for the Standard Model and
MSSM Higgs bosons. Based on a simple detector simulation, we have determined
the integrated luminosity necessary to discover the SM Higgs in the mass range
100-190 GeV. The first phase of the Run 2 Higgs search, with a total integrated
luminosity of 2 fb-1 per detector, will provide a 95% CL exclusion sensitivity
comparable to that expected at the end of the LEP2 run. With 10 fb-1 per
detector, this exclusion will extend up to Higgs masses of 180 GeV, and a
tantalizing 3 sigma effect will be visible if the Higgs mass lies below 125
GeV. With 25 fb-1 of integrated luminosity per detector, evidence for SM Higgs
production at the 3 sigma level is possible for Higgs masses up to 180 GeV.
However, the discovery reach is much less impressive for achieving a 5 sigma
Higgs boson signal. Even with 30 fb-1 per detector, only Higgs bosons with
masses up to about 130 GeV can be detected with 5 sigma significance. These
results can also be re-interpreted in the MSSM framework and yield the required
luminosities to discover at least one Higgs boson of the MSSM Higgs sector.
With 5-10 fb-1 of data per detector, it will be possible to exclude at 95% CL
nearly the entire MSSM Higgs parameter space, whereas 20-30 fb-1 is required to
obtain a 5 sigma Higgs discovery over a significant portion of the parameter
space. Moreover, in one interesting region of the MSSM parameter space (at
large tan(beta)), the associated production of a Higgs boson and a b b-bar pair
is significantly enhanced and provides potential for discovering a non-SM-like
Higgs boson in Run 2.

</DOC>
<DOC>
<DOCNO> 152574 </DOCNO>
D-branes in type I string theory


  We review the boundary state description of D-branes in type I string theory
and show that the only stable non-BPS configurations are the D-particle and the
D-instanton. We also compute the gauge and gravitational interactions of the
non-BPS D-particles and compare them with the interactions of the dual non-BPS
states of the heterotic string, finding complete agreement.

</DOC>
<DOC>
<DOCNO> 9658 </DOCNO>
Electronic structure and magnetism of equiatomic FeN


  In order to investigate the phase stability of equiatomic FeN compounds and
the structure-dependent magnetic properties, the electronic structure and total
energy of FeN with NaCl, ZnS and CsCl structures and various magnetic
configurations are calculated using the first-principles TB-LMTO-ASA method.
Among all the FeN phases considered, the antiferromagnetic NaCl structure with
q=(00pi) is found to have the lowest energy at the theoretical equilibrium
volume. However, the FM NaCl phase lies only 1mRyd higher. The estimated
equilibrium lattice constant for nonmagnetic ZnS-type FeN agrees quite well
with the experimental value, but for the AFM NaCl phase the estimated value is
6.7% smaller than that observed experimentally. For ZnS-type FeN, metastable
magnetic states are found for volumes larger than the equilibrium value. On the
basis of an analysis of the atom- and orbital-projected density of states and
orbital-projected Crystal Orbital Hamilton Population, the iron-nitrogen
interactions in NM ZnS, AFM NaCl and FM CsCl structures are discussed. The
leading Fe-N interactions is due to the d-p iron-nitrogen hybridization, while
considerable s-p and p-p hybridizations are also observed in all three phases.
The iron magnetic moment in FeN is found to be highly sensitive to the
nearest-neighboring Fe-N distance. In particular, the magnetic moment shows an
abrupt drop from a value of about 2 muB to zero with the reduction of the Fe-N
distance for the ZnS and CsCl structures.

</DOC>
<DOC>
<DOCNO> 13404 </DOCNO>
Local Characteristics of Random Motion


  Markovian diffusion processes yield a system of conservation laws which
couple various conditional expectation values (local moments). Solutions of
that closed system of deterministic partial differential equations stand for a
regular alternative to erratic (irregular) sample paths that are associated
with weak solutions of the primordial stochastic differential equations. We
investigate an issue of local characteristics of motion in the non-Gaussian
context, when moments of the probability measure may not exist. A particular
emphasis is put on jump-type stochastic processes with the
Ornstein-Uhlenbeck-Cauchy process as a fully computable exemplary case.

</DOC>
<DOC>
<DOCNO> 116317 </DOCNO>
A classical Over Barrier Model to compute charge exchange between ions


  In this paper we study theoretically the process of electron capture between
one-optical-electron atoms (e.g. hydrogenlike or alkali atoms) and ions at
low-to-medium impact velocities (v/v_e <= 1) working on a modification of an
already developed classical Over Barrier Model (OBM) [V. Ostrovsky, J. Phys. B:
At. Mol. Opt. Phys. {\bf 28} 3901 (1995)], which allows to give a
semianalytical formula for the cross sections. The model is discussed and then
applied to a number of test cases including experimental data as well as data
coming from other sophisticated numerical simulations. It is found that the
accuracy of the model, with the suggested corrections and applied to quite
different situations, is rather high.

</DOC>
<DOC>
<DOCNO> 122441 </DOCNO>
Global MHD Simulations of Cylindrical Keplerian Disks


  This paper presents a series of global three dimensional accretion disk
simulations carried out in the cylindrical limit in which the vertical
component of the gravitational field is neglected. The simulations use a
cylindrical pseudo-Newtonian potential to model the main dynamical properties
of the Schwarzschild metric. The disks are initially constant density with a
Keplerian angular momentum distribution and contain a weak toroidal or vertical
field. These simulations reaffirm many of the conclusions of previous local
simulations. The magnetorotational instability grows rapidly and produces MHD
turbulence with a significant Maxwell stress which drives accretion.
Tightly-wrapped low-$m$ spiral waves are prominent. In some simulations radial
variations in Maxwell stress concentrate gas into rings, creating substantial
spatial inhomogeneities. There is a nonzero stress at the marginally stable
orbit which produces a small decline in specific angular momentum inside the
last stable orbit. Detailed comparisons between simulations are used to examine
the effects of computational domain and equation of state. Simulations that
begin with vertical fields have greater field amplification and higher ratios
of stress to magnetic pressure compared with those beginning with toroidal
fields. In contrast to MHD, hydrodynamics alone neither creates nor sustains
turbulence.

</DOC>
<DOC>
<DOCNO> 40271 </DOCNO>
Search for massive rare particles with MACRO


  Massive rare particles have been searched for in the penetrating cosmic
radiation using the MACRO apparatus at the Gran Sasso National Laboratories.
Liquid scintillators, streamer tubes and nuclear track detectors have been used
to search for magnetic monopoles (MMs).
 Based on no observation of such signals, stringent flux limits are established
for MMs as slow as a few 10^(-5)c. The methods based on the scintillator and on
the nuclear track subdetectors were also applied to search for nuclearites.
Preliminary results of the searches for charged Q-balls are also presented.

</DOC>
<DOC>
<DOCNO> 9226 </DOCNO>
Effect of Non-Magnetic Impurities (Zn,Li) in a Hole Doped Spin-Fermion


  The effect of adding non-magnetic impurities (NMI), such as Zn or Li, to
high-Tc cuprates is studied applying Monte Carlo techniques to a spin-fermion
model. It is observed that adding Li is qualitatively similar to doping with
equal percentages of Sr and Zn. The mobile holes (MH) are trapped by the NMI
and the system remains insulating and commensurate with antiferromagnetic (AF)
correlations. This behavior persists in the region %NMI > %MH. On the other
hand, when %NMI < %MH magnetic and charge incommensurabilities are observed.
The vertical or horizontal hole-rich stripes, present when % NMI=0 upon hole
doping, are pinned by the NMI and tend to become diagonal, surrounding finite
AF domains. The %MH-%NMI plane is investigated. Good agreement with
experimental results is found in the small portion of this diagram where
experimental data are available. Predictions about the expected behavior in the
remaining regions are made.

</DOC>
<DOC>
<DOCNO> 9066 </DOCNO>
Comparison of flux creep an nonlinear E-j approach for analysis of


  Two commonly accepted approaches for simulations of thermally-activated
vortex motion in superconductors are compared. These are (i) the so-called flux
creep approach based on the expression E=vB relating the electric field E to
the velocity v of the thermally-activated flux motion and the local flux
density B, and (ii) the approach employing a phenomenological nonlinear
current-voltage curve, E(j). Our results show that the two approaches give
similar but also distinctly different behaviors for the distributions of
current and flux density in both a long slab and thin strip geometry. The
differences are most pronounced where the local B is small. Magneto-optical
imaging of a YBaCuO thin film carrying a transport current was performed to
compare the simulations with experimental behavior. It is shown that the flux
creep approach describes the experiments far better than simulations based on
the E(j) approach.

</DOC>
<DOC>
<DOCNO> 117114 </DOCNO>
Approximation properties of basis functions in variational three-body


  A new variational basis with well-behaved local approximation properties and
multiple output is proposed for Coulomb systems. The trial function has proper
behaviour at all Coulomb centres. Nonlinear asymptotic parameters are
introduced softly: they do not destroy the self-optimized local behaviour of
the wave function at vanishing interparticle distances. The diagonalization of
the Hamiltonian on a finite Hilbert subspace gives a number of meaningful
eigenvalues. Thus together with the ground state some excited states are also
reliably approximated. For three-body systems all matrix elements are
analytically obtainable up to rational functions of asymptotic parameters. The
feasibility of the new basis usage has been proved by a pilot computer algebra
calculation. The negative sign of an electron pair local energy at their
Coulomb centre has been revealed.
  PACS number: 31.15.Pf

</DOC>
<DOC>
<DOCNO> 9724 </DOCNO>
A non-extensive approach to the time evolution of Lyapunov coefficients


  We study sporadic randomness by means of a non-extensive form of Lyapunov
coefficient. We recover from a different perspective the same conclusion as
that of an earlier work, namely, that the ordinary Pesin theorem applies
(P.Gaspard and X.-J. Wang, Proc. Natl. Acad. Sci. USA {\bf85}, 4591 (1988)).
However, our theoretical analysis allows us to organize the numerical
calculations so as to reveal the slow transition from a temporary form of
non-extensive thermodynamics, corresponding to the prediction of a recent paper
(M. Buiatti, P. Grigolini, A. Montagnini, Phys. Rev. Lett {\bf 82}, 3383
(1999)), to the ordinary extensive thermodynamics. We show that the transition
takes place with a slow decay corresponding to the regression from a
non-equilibrium initial condition to equilibrium condition.

</DOC>
<DOC>
<DOCNO> 99942 </DOCNO>
Similarity Analysis of Nonlinear Equations and Bases of Finite


  We introduce a generalized similarity analysis which grants a qualitative
description of the localised solutions of any nonlinear differential equation.
This procedure provides relations between amplitude, width, and velocity of the
solutions, and it is shown to be useful in analysing nonlinear structures like
solitons, dublets, triplets, compact supported solitons and other patterns. We
also introduce kink-antikink compact solutions for a nonlinear-nonlinear
dispersion equation, and we construct a basis of finite wavelength functions
having self-similar properties.

</DOC>
<DOC>
<DOCNO> 71065 </DOCNO>
Can Precision Measurements of Slepton Masses Probe Right Handed


  In a supersymmetric model, the presence of a right handed neutrino with a
large Yukawa coupling $f_{\nu}$ would affect slepton masses via its
contribution to the renormalization group evolution between the grand
unification and weak scales. Assuming a hierarchichal pattern of neutrino
masses, these effects are large for only the third generation of sleptons. We
construct mass combinations to isolate the effect of $f_{\nu}$ from mass
corrections already expected from tau Yukawa couplings. We then analyze the
size of these effects, assuming that the Super-Kamiokande data constrain 0.033
eV $\alt m_{\nu_{\tau}} \alt 0.1$ eV and that neutrino masses arise via a
see-saw mechanism. We also explore whether these effects might be detectable in
experiments at future $e^+e^-$ linear colliders. We find that $m_{\tnu_{\tau}}$
needs to be measured with a precision of about 2-3% to measure the effect of
$f_{\nu}$ if the neutrino and top Yukawa couplings unify at the grand
unification scale. In a simple case study, we find a precision of only 6-10%
might be attainable after several years of operation. If the neutrino Yukawa
coupling is larger, or in more complicated models of neutrino masses, a
determination of $\ttau_1$ and $\tnu_{\tau}$ masses might provide a signal of a
Yukawa interaction of neutrinos.

</DOC>
<DOC>
<DOCNO> 13272 </DOCNO>
A single-electron inverter


  A single-electron inverter was fabricated that switches from a high output to
a low output when a fraction of an electron is added to the input. For the
proper operation of the inverter, the two single-electron transistors that make
up the inverter must exhibit voltage gain. Voltage gain was achieved by
fabricating a combination of parallel-plate gate capacitors and small tunnel
junctions in a two-layer circuit. Voltage gain of 2.6 was attained at 25 mK and
remained larger than one for temperatures up to 140 mK. The temperature
dependence of the gain agrees with the orthodox theory of single-electron
tunneling.

</DOC>
<DOC>
<DOCNO> 152427 </DOCNO>
Massive Schwinger model and its confining aspects on curved space-time


  Using a covariant method to regularize the composite operators, we obtain the
bosonized action of the massive Schwinger model on a classical curved
background. Using the solution of the bosonic effective action, the energy of
two static external charges with finite and large distance separation on a
static curved space-time is obtained. The confining behavior of this model is
also explicitly discussed.

</DOC>
<DOC>
<DOCNO> 117854 </DOCNO>
Restrictions on parameters of power-law magnetic field decay for


  In this short note we discuss the influence of power-law magnetic field decay
on the evolution of old accreting isolated neutron stars. We show, that,
contrary to exponential field decay (Popov & Prokhorov 2000), no additional
restrictions can be made for the parameters of power-law decay from the
statistics of isolated neutron star candidates in ROSAT observations.
  We also briefly discuss the fate of old magnetars with and without field
decay, and describe parameters of old accreting magnetars.

</DOC>
<DOC>
<DOCNO> 10760 </DOCNO>
Carbon Nanotubes Synthesized in Channels of Alpo4-5 Single Crystals :


  Following the synthesis of aligned single-wall carbon nanotubes in the
channels of AlPO4-5 zeolite single crystals, we present the first X-ray
diffraction and diffuse scattering results. They can be analysed in terms of a
partial filling of the zeolite channels by nanotubes with diameter around 4A.
The possible selection of only one type of nanotube during the synthesis, due
to the constraints imposed by the zeolite host, is discussed.

</DOC>
<DOC>
<DOCNO> 11976 </DOCNO>
Theory of Sinusoidal Modulation of the Resonant Neutron Scattering in


  A model with interlayer pairing is proposed to explain the sinusoidal
modulation of the resonant neutron scattering in high temperature
superconductors. It is found that the interlayer pairing has s-wave symmetry in
the CuO$_2$ plane and has comparable magnitude with the d-wave intralayer
pairing. It is also found that the interlayer pairing mainly affects momentum
close to the hot spots on the Fermi surface while its effect on the gap nodes
is negligible. It is pointed out that these characteristics of the interlayer
pairing can be understood in a model in which the superconducting pairing
originates from the exchange of the antiferromagnetic spin fluctuation.

</DOC>
<DOC>
<DOCNO> 13601 </DOCNO>
Slave Bosons in Radial Gauge: the Correct Functional Integral


  We introduce a new path integral representation for slave bosons in the
radial gauge which is valid beyond the conventional fluctuation corrections to
a mean-field solution. For electronic lattice models, defined on the
constrained Fock space with no double occupancy, all phase fluctuations of the
slave particles can be gauged away if the Lagrange multipliers which enforce
the constraint on each lattice site are promoted to time-dependent fields.
Consequently, only the amplitude (radial part) of the slave boson fields
survives. It has the special property that it is equal to its square in the
physical subspace. This renders the functional integral for the radial field
Gaussian, even when non-local Coulomb-type interactions are included. We
propose i) a continuum integral representation for the set-up of further
approximation schemes, and ii) a discrete representation with an Ising-like
radial variable, valid for long-ranged interactions as well. The latter scheme
can be taken as a starting point for numerical evaluations.

</DOC>
<DOC>
<DOCNO> 99615 </DOCNO>
Koornwinder polynomials and affine Hecke algebras


  In this paper we derive the bi-orthogonality relations, diagonal term
evaluations and evaluation formulas for the non-symmetric Koornwinder
polynomials. For the derivation we use certain representations of the (double)
affine Hecke algebra which were originally defined by Noumi and Sahi. We
furthermore give the explicit connection between the non-symmetric and the
symmetric theory. This leads in particular to new proofs of the orthogonality
relations, quadratic norm evaluations and evaluation formulas for the symmetric
Koornwinder polynomials.

</DOC>
<DOC>
<DOCNO> 118421 </DOCNO>
Bit-String Physics Prediction of eta, The Dark Matter/Baryon Ratio and


  Using a simple combinatorial algorithm for generating finite and discrete
events as our numerical cosmology, we predict that the baryon/photon ratio at
the time of nucleogenesis is $\eta= 1/256^4$, $\Omega_{DM}/\Omega_B= 12.7$ and
(for a cosmological constant of $\Omega_{\Lambda}=0.6\pm 0.1$ predicted on
general grounds by E.D.Jones) that $0.325 > \Omega_M > 0.183 $. The limits are
set not by our theory but by the empirical bounds on the renormalized Hubble
constant of $0.6 < h_0 < 0.8$. If we impose the additional empirical bound of
$t_0 < 14 Gyr$, the predicted upper bound on $\Omega_M$ falls to 0.26. The
predictions of $\Omega_M$ and $\Omega_{\Lambda}$were in excellent agreement
with Glanz' analysis in 1998, and are still in excellent agreement with
Lineweaver's recent analysis despite the reduction of observational uncertainty
by close to an order of magnitude.

</DOC>
<DOC>
<DOCNO> 99738 </DOCNO>
Geometry of the physical phase space in quantum gauge models


  The physical phase space in gauge systems is studied. Effects caused by a
non-Euclidean geometry of the physical phase space in quantum gauge models are
described in the operator and path integral formalisms. The projection on the
Dirac gauge invariant states is used to derive a necessary modification of the
Hamiltonian path integral in gauge theories of the Yang-Mills type with
fermions that takes into account the non-Euclidean geometry of the physical
phase space. The new path integral is applied to resolve the Gribov
obstruction. Applications to the Kogut-Susskind lattice gauge theory are given.
The basic ideas are illustrated with examples accessible for non-specialists.

</DOC>
<DOC>
<DOCNO> 8640 </DOCNO>
Decoherence and Measurement in Open Quantum Systems


  We review results of a recently developed model of a microscopic quantum
system interacting with the macroscopic world components which are modeled by
collections of bosonic modes. The interaction is via a general operator
$\Lambda$ of the system, coupled to the creation and annihilation operators of
the environment modes. We assume that in the process of a nearly instantaneous
quantum measurement, the function of the environment involves two distinct
parts: the pointer and the bath. Interaction of the system with the bath leads
to decoherence such that the system and the pointer both evolve into a
statistical mixture state described by the density matrix such that the system
is in one of the eigenstates of $\Lambda$ with the correct quantum mechanical
probability, whereas the expectation values of pointer operators retain
amplified information on that eigenstate. We argue that this process represents
the initial step of a quantum measurement. Calculation of the elements of the
reduced density matrix of the system and pointer is carried out exactly, and
time dependence of decoherence is identified. We discuss general implications
of our model of energy-conserving coupling to a heat bath for processes of
adiabatic quantum decoherence. We also evaluate changes in the expectation
values of certain pointer operators and suggest that these can be interpreted
as macroscopic indicators of the measurement outcome.

</DOC>
<DOC>
<DOCNO> 80598 </DOCNO>
The Overlap-Dirac Operator: Topology and Chiral Symmetry Breaking


  We review the spectral flow techniques for computing the index of the overlap
Dirac operator including results relevant for SUSY Yang-Mills theories. We
describe properties of the overlap Dirac operator, and methods to implement it
numerically. We use the results from the spectral flow to illuminate the
difficulties in numerical calculations involving domain wall and overlap
fermions.

</DOC>
<DOC>
<DOCNO> 100166 </DOCNO>
Mori Dream Spaces and GIT


  The main goal of this paper is to study varieties with the best possible Mori
theoretic properties (measured by the existence of a certain decomposition of
the cone of effective divisors). We call such a variety a Mori Dream Space.
There turn out to be many examples, including quasi-smooth projective toric (or
more generally, spherical) varieties, many GIT quotients, and log Fano 3-folds.
We characterize Mori dream spaces as GIT quotients of affine varieties by a
torus in a manner generalizing Cox's construction of toric varieties as
quotients of affine space. Via the quotient description, the chamber
decomposition of the cone of divisors in Mori theory is naturally identified
with the decomposition of the G-ample cone from geometric invariant theory. In
particular every rational contraction of a Mori dream space comes from GIT, and
all possible factorizations of a rational contraction can be read off from the
chamber decomposition.

</DOC>
<DOC>
<DOCNO> 12210 </DOCNO>
Information theory and learning: a physical approach


  We try to establish a unified information theoretic approach to learning and
to explore some of its applications. First, we define {\em predictive
information} as the mutual information between the past and the future of a
time series, discuss its behavior as a function of the length of the series,
and explain how other quantities of interest studied previously in learning
theory - as well as in dynamical systems and statistical mechanics - emerge
from this universally definable concept. We then prove that predictive
information provides the {\em unique measure for the complexity} of dynamics
underlying the time series and show that there are classes of models
characterized by {\em power-law growth of the predictive information} that are
qualitatively more complex than any of the systems that have been investigated
before. Further, we investigate numerically the learning of a nonparametric
probability density, which is an example of a problem with power-law
complexity, and show that the proper Bayesian formulation of this problem
provides for the `Occam' factors that punish overly complex models and thus
allow one {\em to learn not only a solution within a specific model class, but
also the class itself} using the data only and with very few a priori
assumptions. We study a possible {\em information theoretic method} that
regularizes the learning of an undersampled discrete variable, and show that
learning in such a setup goes through stages of very different complexities.
Finally, we discuss how all of these ideas may be useful in various problems in
physics, statistics, and, most importantly, biology.

</DOC>
<DOC>
<DOCNO> 13318 </DOCNO>
The fabrication of reproducible superconducting scanning tunneling


  Superconducting scanning tunneling microscope tips have been fabricated with
a high degree of reproducibility. The fabrication process relies on sequential
deposition of superconducting Pb and a proximity-coupled Ag capping layer onto
a Pt/Ir tip. The tips were characterized by tunneling into both normal-metal
and superconducting films. The simplicity of the fabrication process, along
with the stability and reproducibility of the tips, clear the way for tunneling
studies with a well-characterized, scannable superconducting electrode.

</DOC>
<DOC>
<DOCNO> 10053 </DOCNO>
Supercooled fluid-fluid phase transition in three dimensions from a


  To study the possibility of a fluid-fluid phase transition, we analyze a
three-dimensional soft-core isotropic potential for a one-component system. We
utilize two independent numerical approaches, (i) integral equation in the
hypernetted-chain approximation and (ii) molecular dynamics simulations, and
find for both approaches a fluid-fluid phase transition as well as the
conventional gas-liquid critical point. We also study the possible existence of
a triple point in the supercooled fluid phase at which three phases---gas,
high-density fluid, and low-density fluid---coexist.

</DOC>
<DOC>
<DOCNO> 9942 </DOCNO>
Six-Vertex Model with Domain Wall Boundary Conditions and One-Matrix


  The partition function of the six-vertex model on a square lattice with
domain wall boundary conditions (DWBC) is rewritten as a hermitean one-matrix
model or a discretized version of it (similar to sums over Young diagrams),
depending on the phase. The expression is exact for finite lattice size, which
is equal to the size of the corresponding matrix. In the thermodynamic limit,
the matrix integral is computed using traditional matrix model techniques, thus
providing a complete treatment of the bulk free energy of the six-vertex model
with DWBC in the different phases. In particular, in the anti-ferroelectric
phase, the bulk free energy and a subdominant correction are given exactly in
terms of elliptic theta functions.

</DOC>
<DOC>
<DOCNO> 9781 </DOCNO>
Diagrammatic Theory of Anderson Impurity Models: Fermi and Non-Fermi


  We review a recently developed method, based on a pseudoparticle
representation of correlated electrons, to describe both Fermi liquid and
non-Fermi liquid behavior in quantum impurity systems. The role of the
projection onto the physical Hilbert space and the impossibility of slave boson
condensation are discussed. By summing the leading coherent spin and charge
fluctuation processes in a fully self-consistent and gauge invariant way one
obtains the correct infrared behavior of the pseudoparticles. The temperature
dependence of the spin susceptibility for the single channel and two-channel
Anderson models is calculated and found to agree well with exact results.

</DOC>
<DOC>
<DOCNO> 67796 </DOCNO>
Local Finite Density Theory, Statistical Blocking and Color


  The motivation for the development of a local finite density theory is
discussed. One of the problems related to an instability in the baryon number
fluctuation of the chiral symmetry breaking phase of the quark system in the
local theory is shown to exist. Such an instability problem is removed by
taking into account the statistical blocking effects for the quark propagator,
which depends on a macroscopic {\em statistical blocking parameter} $\epsilon$.
This new frame work is then applied to study color superconducting phase of the
light quark system.

</DOC>
<DOC>
<DOCNO> 116569 </DOCNO>
Frequency stabilization of a monolithic Nd:YAG ring laser by controlling


  The frequency of a 700mW monolithic non-planar Nd:YAG ring laser (NPRO)
depends with a large coupling coefficient (some MHz/mW) on the power of its
laser-diode pump source. Using this effect we demonstrate the frequency
stabilization of an NPRO to a frequency reference by feeding back to the
current of its pump diodes. We achieved an error point frequency noise smaller
than 1mHz/sqrt(Hz), and simultaneously a reduction of the power noise of the
NPRO by 10dB without an additional power stabilization feed-back system.

</DOC>
<DOC>
<DOCNO> 71031 </DOCNO>
Pair Production by a Constant External Field in Noncommutative QED


  In this paper we study QED on the noncommutative space in the constant
electro-magnetic field background. Using the explicit solutions of the
noncommutative version of Dirac equation in such background, we show that there
are well-defined in and out -going asymptotic states and also there is a causal
Green's function. We calculate the pair production rate in this case. We show
that at tree level noncommutativity will not change the pair production and the
threshold electric field. We also calculate the pair production rate
considering the first loop corrections. In this case we show that the threshold
electric field is decreased by the noncommutativity effects.

</DOC>
<DOC>
<DOCNO> 69979 </DOCNO>
Low energy analysis of the nucleon electromagnetic form factors


  We analyze the electromagnetic form factors of the nucleon to fourth order in
relativistic baryon chiral perturbation theory. We employ the recently proposed
infrared regularization scheme and show that the convergence of the chiral
expansion is improved as compared to the heavy fermion approach. We also
discuss the inclusion of vector mesons and obtain an accurate description of
all four nucleon form factors for momentum transfer squared up to Q^2 \simeq
0.4 GeV^2.

</DOC>
<DOC>
<DOCNO> 8684 </DOCNO>
Comment on "Kagome Lattice Antiferromagnet Stripped to Its Basics"


  Density matrix renormalization group (DMRG) calculations on large systems (up
to 3096 spins) indicate that the ground state of the Heisenberg model on a
3-chain Kagome strip is spontaneously dimerized. This system has degenerate
ground states and a gap to triplet and singlet excitations. These results are
in direct contradiction with recent results of Azaria et al (Phys. Rev. Lett.
81, 1694 (1998)) and suggest a need for a reexamination of the underlying field
theory.

</DOC>
<DOC>
<DOCNO> 170671 </DOCNO>
su(2) and su(1,1) displaced number states and their nonclassical


  We study su(2) and su(1,1) displaced number states. Those states are
eigenstates of density-dependent interaction systems of quantized radiation
field with classical current. Those states are intermediate states
interpolating between number and displaced number states. Their photon number
distribution, statistical and squeezing properties are studied in detail. It is
show that these states exhibit strong nonclassical properties.

</DOC>
<DOC>
<DOCNO> 100668 </DOCNO>
Structure of Divergence-Free Lie Algebras


  One of the four well-known series of simple Lie algebras of Cartan type is
the series of Lie algebras of Special type, which are divergence-free Lie
algebras associated with polynomial algebras and the operators of taking
partial derivatives, connected with volume-preserving diffeomorphisms. In this
paper, we determine the structure space of the divergence-free Lie algebras
associated with pairs of a commutative associative algebra with an identity
element and its finite-dimensional commutative locally-finite derivation
subalgebra such that the commutative associative algebra is derivation-simple
with respect to the derivation subalgebra.

</DOC>
<DOC>
<DOCNO> 120177 </DOCNO>
Gamma-ray loud quasars: a view with BeppoSAX


  We present BeppoSAX observations of three gamma-ray emitting quasars, namely
0836+710, 1510-089 and 2230+114. The three objects have been detected up to 100
keV showing extremely flat power-law spectra above 2 keV (energy index
alpha_{2-10}=0.3-0.5). The soft X-ray spectrum of 0836+710 implies either an
absorption column density higher than the galactic one or an intrinsically very
hard slope (alpha_{0.1-1}=-0.2) below 1 keV. 1510-089 shows a soft excess, with
the low energy spectrum steeper (alpha_{0.1-1}=1.6) than the high energy
power-law. The results are discussed in the framework of current Inverse
Compton models for the high energy emission of Flat Spectrum Radio Quasars and
are used to estimate the physical quantities in the jet emitting region and to
shed light on the energy transport mechanisms in jets. Finally we discuss the
estimates of the jet luminosity in the context of the Blandford & Znajek
mechanism for jet production.

</DOC>
<DOC>
<DOCNO> 71511 </DOCNO>
Anomalies and WZW-term of two-flavour QCD


  The U(2)_R x U(2)_L symmetry of QCD with two massless flavours is subject to
anomalies which affect correlation functions involving the singlet currents
A^0_\mu or V^0_\mu. These are relevant for pion-photon interactions, because -
for two flavours - the electromagnetic current contains a singlet piece. We
give the effective Lagrangian required for the corresponding low energy
analysis to next-to-leading order, without invoking an expansion in the mass of
the strange quark. In particular, the Wess-Zumino-Witten term that accounts for
the two-flavour anomalies within the effective theory is written down in closed
form.

</DOC>
<DOC>
<DOCNO> 12323 </DOCNO>
Damped Bogoliubov excitations of a condensate interacting with a static


  We calculate the damping of condensate collective excitations at finite
temperatures arising from the lack of equilibrium between the condensate and
thermal atoms. We neglect the non-condensate dynamics by fixing the thermal
cloud in static equilibrium. We derive a set of generalized Bogoliubov
equations for finite temperatures that contain an explicit damping term due to
collisional exchange of atoms between the two components. We have numerically
solved these Bogoliubov equations to obtain the temperature dependence of the
damping of the condensate modes in a harmonic trap. We compare these results
with our recent work based on the Thomas-Fermi approximation.

</DOC>
<DOC>
<DOCNO> 13390 </DOCNO>
Thermodynamics and transport properties of interacting systems with


  The review of the modern results in the theoretical and experimental study of
the localized interacting electrons is given. After theoretical prediction of
the Coulomb gap and the new temperature law in the variable range hopping
conduction many efforts have been made to discover it experimentally. The most
important of them are attempts to demonstrate experimentally that the long
range Coulomb interaction is not screened in this system and that it is the
origin of the gap. The next stage begins when the recent experiments have
discovered glassy properties of the interacting system with localized
electrons. This review is concentrated on the origin of the glassy properties
of this system and it connects the glassy properties with another interesting
phenomenon - insulator-metal transition.

</DOC>
<DOC>
<DOCNO> 67882 </DOCNO>
Observing the Odderon: Tensor Meson Photoproduction


  We calculate high-energy photoproduction of the tensor meson $f_2(1270)$ by
odderon and photon exchange in the reaction $\gamma + {\rm{p}} \to f_2(1270) +
{\rm{X}}$, where X is either the nucleon or the sum of the N(1520) and N(1535)
baryon resonances. Odderon exchange dominates except at very small transverse
momentum, and we find a cross section of about 20 nb at a centre-of-mass energy
of 20 GeV. This result is compared with what is currently known experimentally
about $f_2$ photoproduction. We conclude that odderon exchange is not ruled out
by present data. On the contrary, an odderon-induced cross section of the above
magnitude may help to explain a puzzling result observed by the E687
experiment.

</DOC>
<DOC>
<DOCNO> 152360 </DOCNO>
Finite temperature resolution of the Klebanov-Tseytlin singularity


  Naked singularities in the gravitational backgrounds dual to gauge theories
can be hidden behind the black hole horizon. We present an exact black hole
solution in the Klebanov-Tseytlin geometry [hep-th/0002159]. Our solution
realizes Maldacena dual of the finite temperature N=1 duality cascade of
[hep-th/0007191] above the temperature of the chiral symmetry breaking. We
compare the Bekenstein-Hawking entropy of the black hole with the entropy of
the SU(N+M)xSU(N) gauge theory.

</DOC>
<DOC>
<DOCNO> 121760 </DOCNO>
The recent history of the X-ray absorber in NGC3516


  We present two BeppoSAX observations of the bright Seyfert 1 galaxy NGC3516,
performed four months apart (late 1996/early 1997). The earlier spectrum is
considerably weaker and harder in the whole 0.1-50 keV energy range. In
addition, the warm absorber oxygen features, which were already observed with
ROSAT (Mathur et al. 1997) and ASCA (Kriss et al. 1996), are much less
pronounced. The most straightforward explanation is that in 1996 November
NGC3516 was being seen through a substantial (N_H ~ 10^22 atoms/cm/cm) column
of cold material. This is the first confirmation with modern instrumentation
that NGC3516 indeed undergoes phases of strong cold X-ray absorption. We
speculate that these intervals may be connected to the onset of the remarkably
variable UV absorption system, making NGC3516 the best known example of
low-luminosity Broad Absorption Line (BAL) quasar. The absorbing matter could
be provided by clouds ablated from the rim of the circumnuclear molecular
torus, seen at a rather high inclination angle.

</DOC>
<DOC>
<DOCNO> 9626 </DOCNO>
Generalized strategies in the Minority Game


  We show analytically how the fluctuations (i.e. standard deviation) in the
Minority Game (MG) can be made to decrease below the random coin-toss limit if
the agents use more general behavioral strategies. This suppression of the
standard deviation results from a cancellation between the actions of a crowd,
in which agents act collectively and make the same decision, and an anticrowd
in which agents act collectively by making the opposite decision to the crowd.

</DOC>
<DOC>
<DOCNO> 72002 </DOCNO>
A Small Cosmological Constant from Warped Compactification with Branes


  We present a possible explanation for the smallness of the observed
cosmological constant using a variant of the Randall-Sundrum(RS)-
Goldberger-Wise paradigm for a warped extra dimension. In contrast to RS, we
imagine that we are living on the positive tension Planck brane, or on a
zero-tension TeV brane. In our model there are two solutions for the scalar
field in the bulk and the corresponding brane separations, one of which is
tuned to have zero cosmological constant. We show that in the other solution,
which is a false vacuum state, the 4-D cosmological constant can be naturally
small, due to exponential suppression by the warp factor. The radion is in the
milli-eV mass range, and if we live on a TeV brane its couplings are large
enough that it can measurably alter the gravitational force at submillimeter
distances. In this case the Kaluza-Klein excitations of the graviton can also
contribute to submillimeter deviations from Newtonian gravity, and we have in
addition the collider phenomenology of the usual TeV-scale radion.

</DOC>
<DOC>
<DOCNO> 10012 </DOCNO>
Franck-Condon-Broadened Angle-Resolved Photoemission Spectra Predicted


  The sudden photohole of least energy created in the photoemission process is
a vibrationally excited state of a small polaron. Therefore the photoemission
spectrum in LaMnO3 is predicted to have multiple Franck-Condon vibrational
sidebands. This generates an intrinsic line broadening approximately 0.5 eV.
The photoemission spectral function has two peaks whose central energies
disperse with band width approximately 1.2 eV. Signatures of these phenomena
are predicted to appear in angle-resolved photoemission spectra.

</DOC>
<DOC>
<DOCNO> 11702 </DOCNO>
Josephson vortex in a ratchet potential: Theory


  We propose a new type of Josephson vortex ratchet. In this system a Josephson
vortex moves in a periodic asymmetric potential under the action of a
deterministic or random force with zero time average. For some implementations
the amplitude of the potential can be controlled during the experiment, thus,
allowing to tune the performance of the system and build rocking as well as
flashing ratchets. We present a model describing the dynamics of the fluxon in
such a system, show numerical simulation results, and discuss the differences
between conventional and Josephson vortex ratchets. The investigation of this
system may lead to the development of the fluxon rectifier --- a device which
produces a quantized dc voltage from colored noise (non-equilibrium
fluctuations).

</DOC>
<DOC>
<DOCNO> 72112 </DOCNO>
QCD Radiation off Heavy Particles


  An algorithm for an improved description of final-state QCD radiation is
introduced. It is matched to the first-order matrix elements for gluon emission
in a host of decays, for processes within the Standard Model and the Minimal
Supersymmetric extension thereof.

</DOC>
<DOC>
<DOCNO> 84262 </DOCNO>
Are Simple Real Pole Solutions Physical?


  We consider exact solutions generated by the inverse scattering technique,
also known as the soliton transformation. In particular, we study the class of
simple real pole solutions. For quite some time, those solutions have been
considered interesting as models of cosmological shock waves. A coordinate
singularity on the wave fronts was removed by a transformation which induces a
null fluid with negative energy density on the wave front. This null fluid is
usually seen as another coordinate artifact, since there seems to be a general
belief that that this kind of solution can be seen as the real pole limit of
the smooth solution generated with a pair of complex conjugate poles in the
transformation. We perform this limit explicitly, and find that the belief is
unfounded: two coalescing complex conjugate poles cannot yield a solution with
one real pole. Instead, the two complex conjugate poles go to a different
limit, what we call a ``pole on a pole''. The limiting procedure is not unique;
it is sensitive to how quickly some parameters approach zero. We also show that
there exists no improved coordinate transformation which would remove the
negative energy density. We conclude that negative energy is an intrinsic part
of this class of solutions.

</DOC>
<DOC>
<DOCNO> 120409 </DOCNO>
Mining The Local Universe for Data: the QSO Luminosity Function with the


  We present progress results of a new survey for bright QSOs (V<14.5, R<15.4,
B_J<15.2) covering the whole sky at |b|>30. The surface density of QSOs
brighter than B_J=14.8 turns out to be $2.9 \pm 0.8 \cdot 10^{-3} deg^{-2}$.
The optical Luminosity Function at 0.04 < z < 0.3 shows significant departures
from the standard pure luminosity evolution, providing new insights in the
modelling of the QSO phenomenon.

</DOC>
<DOC>
<DOCNO> 178853 </DOCNO>
Chiral unitary approach to the K^- deuteron scattering length


  Starting from a recent model where the Kbar N amplitudes are evaluated from
the chiral Lagrangians using a coupled channel unitary method, we evaluate here
the scattering length for K^- deuteron scattering. We find that the double
scattering contribution is very large compared to the impulse approximation and
that the charge exchange contribution of this rescattering is as large as the
sequential K^- scattering on the two nucleons. Higher order rescattering
corrections are evaluated using coupled channels with K^- and Kbar^0 within the
integral form of the fixed centre approximation to the Faddeev equations. The
higher order corrections involving intermediate pions and hyperons are found
negligible.

</DOC>
<DOC>
<DOCNO> 10788 </DOCNO>
Uniaxial Lifshitz Point at $O(\epsilon_L^2)$


  The critical exponents $\nu_{L2}, \eta_{L2}$ and $\gamma_{L2}$ of a uniaxial
Lifshitz point are calculated at two-loop level using renormalization group and
$\epsilon_{L}$-expansion techniques. We found a new constraint involving the
loop momenta along the competition axis, which allows to solve the two-loop
integrals. The exponent $\gamma_{L2}$ obtained using our method is in good
agreement with numerical estimates based on Monte Carlo simulations.

</DOC>
<DOC>
<DOCNO> 174484 </DOCNO>
Sideward Flow in Au + Au Collisions Between 2A GeV and 8A GeV


  Using the large acceptance Time Projection Chamber of experiment E895 at
Brookhaven, measurements of collective sideward flow in Au + Au collisions at
beam energies of 2, 4, 6 and 8A GeV are presented in the form of in-plane
transverse momentum <Px> and the first Fourier coefficient of azimuthal
anisotropy v_1. These measurements indicate a smooth variation of sideward flow
as a function of beam energy. The data are compared with four nuclear transport
models which have an orientation towards this energy range. All four exhibit
some qualitative trends similar to those found in the data, although none shows
a consistent pattern of agreement within experimental uncertainties.

</DOC>
<DOC>
<DOCNO> 102853 </DOCNO>
An expansion of the Jones representation of genus 2 and the Torelli


  We study the algebraic property of the representation of the mapping class
group of a closed oriented surface of genus 2 constructed by VFR Jones [Annals
of Math. 126 (1987) 335-388]. It arises from the Iwahori-Hecke algebra
representations of Artin's braid group of 6 strings, and is defined over
integral Laurent polynomials Z[t, t^{-1}]. We substitute the parameter t with
-e^{h}, and then expand the powers e^h in their Taylor series. This expansion
naturally induces a filtration on the Torelli group which is coarser than its
lower central series. We present some results on the structure of the
associated graded quotients, which include that the second Johnson homomorphism
factors through the representation. As an application, we also discuss the
relation with the Casson invariant of homology 3-spheres.

</DOC>
<DOC>
<DOCNO> 68503 </DOCNO>
Axial vector current in an electromagnetic field and low-energy


  An expression for the axial vector current in a strong, slowly varying
electromagnetic field is obtained. We apply this expression to the construction
of the effective action for low-energy neutrino-photon interactions.

</DOC>
<DOC>
<DOCNO> 102563 </DOCNO>
A canonical hyperkaehler metric on the total space of a cotangent bundle


  A canonical hyperkaehler metric on the total space $T^*M$ of a cotangent
bundle to a complex manifold $M$ has been constructed recently by the author
(see alg-geom/9710026). This paper presents the results of alg-geom/9710026 in
a streamlined and simplified form. The only new result is an explicit formula
obtained for the case when $M$ is an Hermitian symmetric space.

</DOC>
<DOC>
<DOCNO> 11774 </DOCNO>
Evidence for the exponential distribution of income in the USA


  Using tax and census data, we demonstrate that the distribution of individual
income in the USA is exponential. Our calculated Lorenz curve without fitting
parameters and Gini coefficient 1/2 agree well with the data. From the
individual income distribution, we derive the distribution function of income
for families with two earners and show that it also agrees well with the data.
The family data for the period 1947-1994 fit the Lorenz curve and Gini
coefficient 3/8=0.375 calculated for two-earners families.

</DOC>
<DOC>
<DOCNO> 13236 </DOCNO>
Giant Magnetoresistance at the Interface of Iron Thin Films


  Ag/Fe/Ag and Cr/Fe/Cr trilayers with a single $25 nm$ thick ferromagnetic
layer exhibit giant magnetoresistance (GMR) type behavior. The resistance
decreases for parallel and transversal magnetic field alignements with a
Langevin-type magnetic field dependence up to B=12 T. The phenomenon is
explained by a granular interface structure. Results on Fe/Ag multilayers are
also interpreted in terms of a granular interface magnetoresistance.

</DOC>
<DOC>
<DOCNO> 99567 </DOCNO>
Espace des modules des faisceaux semi-stables de rang 2 et de classes de


  In this note we study the moduli space of rank two semistable sheaves on a
smooth cubic hypersurface $X\subset\mathbb{P}^{4}$ with $c_{1}=0$, $c_{2}=2$
and $c_{3}=0$. We show that it is isomorphic to the blow-up of the intermediate
jacobian $J(X)$ of $X$ along the Fano surface of $X$. We complete previous
results of Iliev-Markushevich AG/9910058 and Markushevich-Tikhomirov
AG/9910063.

</DOC>
<DOC>
<DOCNO> 71966 </DOCNO>
Observational constraints on models of inflation from the density


  Present data require a spectral index $n\gsim 0.95$ at something like
1-$\sigma$ level. If this lower bound survives it will constrain `new' and
`modular' inflation models, while raising it to 1.00 would rule out all of
these models plus many others.
  After inflation, gravitinos are created by the oscillating field until the
`intermediate' epoch when the Hubble parameter falls below the gravitino mass,
or reheating, whichever is earlier. In a wide range of parameter space, these
gravitinos are more abundant than those from thermal collisions, leading to
stronger cosmological constraints.

</DOC>
<DOC>
<DOCNO> 178401 </DOCNO>
Chirality of nuclear rotation


  It is shown that the rotating mean field of triaxial nuclei can break the
chiral symmetry. Two nearly degenerate $\Delta I =1 $ rotational bands
originate from the left-handed and right-handed solution.

</DOC>
<DOC>
<DOCNO> 150524 </DOCNO>
D-Dimensional Conformal $\sigma$-models and Topological Excitations


  The D-dimensional conformal nonlinear sigma-models (NSM) sre constructed. It
is shown that the NSM on spaces with $\pi_{D-1} = \mathbb {Z}$ have the
topological solutions of a "hedgehog" and "anti-hedgehog" types with
logarithmic energies. For spaces with $\pi_D \ne 0$ they have also the
topological excitations of instanton types with finite energies.

</DOC>
<DOC>
<DOCNO> 83189 </DOCNO>
Separating the complexity classes NL and NP


  Withdrawn since -order- was overlooked. First order reductions without order
are much too weak to separate.

</DOC>
<DOC>
<DOCNO> 10991 </DOCNO>
Transport on Directed Percolation Clusters


  We study random lattice networks consisting of resistor like and diode like
bonds. For investigating the transport properties of these random resistor
diode networks we introduce a field theoretic Hamiltonian amenable to
renormalization group analysis. We focus on the average two-port resistance at
the transition from the nonpercolating to the directed percolating phase and
calculate the corresponding resistance exponent $\phi$ to two-loop order.
Moreover, we determine the backbone dimension $D_B$ of directed percolation
clusters to two-loop order. We obtain a scaling relation for $D_B$ that is in
agreement with well known scaling arguments.

</DOC>
<DOC>
<DOCNO> 100837 </DOCNO>
Rigidity for Quasi-Mobius group actions


  Suppose G is a hyperbolic group whose boundary has topological dimension k.
If the boundary is quasisymmetrically homeomorphic to an Ahlfors k-regular
metric space, then, modulo a finite normal subgroup, G is isomorphic to a
uniform lattice in the isometry group of hyperbolic (k+1)-space.

</DOC>
<DOC>
<DOCNO> 102046 </DOCNO>
Geometry of Projective Planes over Two-Dimensional Algebras


  The authors study smooth lines on projective planes over the algebra C of
complex numbers, the algebra C^1 of double numbers, and the algebra C^0 of dual
numbers. In the space RP^5, to these smooth lines there correspond families of
straight lines describing point three-dimensional tangentially degenerate
submanifolds X^3 of rank 2. The authors study focal properties of these
submanifolds and prove that they represent examples of different types of
tangentially degenerate submanifolds. Namely, the submanifold X^3,
corresponding in RP^5 to a smooth line \gamma of the projective plane C, does
not have real singular points, the submanifold X^3, corresponding in RP^5 to a
smooth line \gamma of the projective plane C^1 P^2, bears two plane singular
lines, and finally the submanifold X^3, corresponding in RP^5 to a smooth line
\gamma of the projective plane C^0 P^2, bears one singular line.

</DOC>
<DOC>
<DOCNO> 7838 </DOCNO>
A microscopic model for d-wave charge carrier pairing and


  We investigate a microscopic model for strongly correlated electrons with
both on-site and nearest neighbor Coulomb repulsion on a 2D square lattice.
This exhibits a state in which electrons undergo a ``somersault'' in their
internal spin-space (spin-flux) as they traverse a closed loop in external
coordinate space. When this spin-1/2 antiferromagnetic (AFM) insulator is
doped, the ground state is a liquid of charged, bosonic meron-vortices, which
for topological reasons are created in vortex-antivortex pairs. The magnetic
exchange energy of the distorted AFM background leads to a logarithmic
vortex-antivortex attraction which overcomes the direct Coulomb repulsion
between holes localized on the vortex cores. This leads to the appearance of
pre-formed charged pairs. We use the Configuration Interaction (CI) Method to
study the quantum translational and rotational motion of various charged
magnetic solitons and soliton pairs. The CI method systematically describes
fluctuation and quantum tunneling corrections to the Hartree-Fock Approximation
(HFA). We find that the lowest energy charged meron-antimeron pairs exhibit
d-wave rotational symmetry, consistent with the symmetry of the cuprate
superconducting order parameter. For a single hole in the 2D AFM plane, we find
a precursor to spin-charge separation in which a conventional charged
spin-polaron dissociates into a singly charged meron-antimeron pair. This model
provides a unified microscopic basis for (i) non-Fermi-liquid transport
properties, (ii) d-wave preformed charged carrier pairs, (iii) mid-infrared
optical absorption, (iv) destruction of AFM long range order with doping and
other magnetic properties, and (v) certain aspects of angled resolved
photo-emission spectroscopy (ARPES).

</DOC>
<DOC>
<DOCNO> 72299 </DOCNO>
Electroweak Precision Tests with GigaZ


  By running the prospective high-energy e^+e^- collider TESLA in the GigaZ
mode on the Z resonance, experiments can be performed on the basis of more than
10^9 Z events. This will allow the measurement of the effective electroweak
mixing angle to an accuracy of \delta sin^2(theta_W,eff) \approx \pm 10^-5. The
W boson mass is likewise expected to be measurable with an error of \delta M_W
\approx \pm 6 MeV near the W^+W^ threshold. We review the electroweak precision
tests that can be performed with these high precision measurements within the
Standard Model (SM) and its minimal Supersymmetric extension (MSSM). The
complementarity of direct measurements at a prospective linear e^+e^- collider
and indirect constraints following from measurements performed at GigaZ is
emphasized.

</DOC>
<DOC>
<DOCNO> 9918 </DOCNO>
Two-Dimensional Modeling of Soft Ferromagnetic Films


  We examine the response of a soft ferromagnetic film to an in-plane applied
magnetic field. Our theory, based on asymptotic analysis of the micromagnetic
energy in the thin-film limit, proceeds in two steps: first we determine the
magnetic charge density by solving a convex variational problem; then we
construct an associated magnetization field using a robust numerical method.
Experimental results show good agreement with the theory. Our analysis is
consistent with prior work by van den Berg and by Bryant and Suhl, but it goes
much further; in particular it applies even for large fields which penetrate
the sample.

</DOC>
<DOC>
<DOCNO> 101560 </DOCNO>
Embeddings of Schur functions into types B/C/D


  We consider the problem of embedding the semi-ring of Schur-positive
symmetric polynomials into its analogue for the classical types $B/C/D$. If we
preserve highest weights and add the additional Lie-theoretic parity assumption
that the weights in images of Schur functions lie in a single translate of the
root lattice, there are exactly two solutions. These naturally extend the
Kirillov--Reshetikhin decompositions of representations of symplectic and
orthogonal quantum affine algebras $U_q(\hat{g})$ (some still conjectural, some
recently proven).

</DOC>
<DOC>
<DOCNO> 102899 </DOCNO>
Electromagnetism and Gauge Theory on the Permutation Group $S_3$


  Using noncommutative geometry we do U(1) gauge theory on the permutation
group $S_3$. Unlike usual lattice gauge theories the use of a nonAbelian group
here as spacetime corresponds to a background Riemannian curvature. In this
background we solve spin 0, 1/2 and spin 1 equations of motion, including the
spin 1 or `photon' case in the presence of sources, i.e. a theory of classical
electromagnetism. Moreover, we solve the U(1) Yang-Mills theory (this differs
from the U(1) Maxwell theory in noncommutative geometry), including the moduli
spaces of flat connections. We show that the Yang-Mills action has a simple
form in terms of Wilson loops in the permutation group, and we discuss aspects
of the quantum theory.

</DOC>
<DOC>
<DOCNO> 150819 </DOCNO>
On the String Description of Confinement


  A non supersymmetric string background, directly derived from the string soft
dilaton theorem, is used to compute, in the semiclassical approximation, the
expectation value of Wilson loops in static gauge. The resulting potential
shares common features with the one obtained through Schwarzschild-anti de
Sitter spacetime metrics. In particular a linear confining potential appears
naturally.

</DOC>
<DOC>
<DOCNO> 72179 </DOCNO>
Renormalization-Scale Invariance, Minimal Sensitivity, and the Inclusive


  Known perturbative expressions for the decay rates of 115 GeV Higgs particle
into either two gluons or a $b\bar{b}$ pair are shown to exhibit
renormalization-scale-($\mu$)-dependence that is largely removed via
renormalization-group/Pade-approximant estimates of these rates' next order
contributions. The extrema in $\mu$ characterizing both rates, as determined
from fully-known orders of perturbation theory, are very nearly equal to
corresponding $\mu$-insensitive rates obtained via estimation of their next
order contributions, consistent with "minimal-sensitivity" expectations.

</DOC>
<DOC>
<DOCNO> 8738 </DOCNO>
Influence of reptations on conformations of the homopolymer in Monte


  We study the role of topological restrictions for the conformational
structure of a nonphantom homopolymer chain in a lattice Monte Carlo model. In
the athermal regime we find that the standard Metropolis algorithm violates the
detailed balance condition if both local monomer and global reptational moves
are included. However, if about 1 reptation is performed per N local moves the
balance is recovered and we obtain the Flory exponent value close to nu=0.588,
where N is the degree of polymerisation. We also find that the structure of the
collapsed globule is different at equilibrium from that after the late stage of
folding kinetics. Namely, due to reptations the end, and even more so, the
penultimate monomer groups tend to be buried inside the globule core with other
monomers thus being more exposed to the surface.

</DOC>
<DOC>
<DOCNO> 151795 </DOCNO>
Some notes on string theory


  We start from a quantum computational principle suggested for string theory
in a previous paper and discuss how it might lead to a dynamical principle
implying the correct classical gravitational limit. Besides this, we briefly
look at some structural properties of moduli space.

</DOC>
<DOC>
<DOCNO> 170118 </DOCNO>
Decoherence and Entanglement in Two-mode Squeezed Vacuum States


  I investigate the decoherence of two-mode squeezed vacuum states by analyzing
the relative entropy of entanglement. I consider two sources of decoherence:
(i) the phase damping and (ii) the amplitude damping due to the coupling to the
thermal environment. In particular, I give the exact value of the relative
entropy of entanglement for the phase damping model. For the amplitude damping
model, I give an upper bound for the relative entropy of entanglement, which
turns out to be a good approximation for the entanglement measure in usual
experimental situations.

</DOC>
<DOC>
<DOCNO> 84748 </DOCNO>
Stability of the GRS Model


  We discuss the compatibility between the weaker energy condition and the
stability of Gregory, Rubakov and Sibiryakov (GRS) model. Because the GRS
spacetime violates the weak energy condition, it may cause the instability. In
the GRS model, the four dimensional gravity can be described by the massive KK
modes with the resonance. Hence, instead of considering the weaker energy
condition, we require for the stability of this model: no tachyon and no ghost
condition for graviton modes ($h_{\mu\nu}$). No tachyonic condition ($m^2_h
\geq 0$) is satisfied because the lowest state $m_h=0$ is supersymmetric vacuum
state. Further, no ghost state condition is achieved if one requires some
relations for the matter source: $2T_{55}= T^{\mu}_{\mu}=3(T_{22}+T_{33})$. It
turns out that, although the GRS spacetime does not satisfy the weaker energy
condition, it is stable against small perturbation.

</DOC>
<DOC>
<DOCNO> 11843 </DOCNO>
Using mean field theory to determine the structure of uniform fluids


  The structure of a uniform simple liquid is related to that of a reference
fluid with purely repulsive intermolecular forces in a self-consistently
determined external reference field (ERF) phi_ R. The ERF can be separated into
a harshly repulsive part phi_ R0 generated by the repulsive core of a reference
particle fixed at the origin and a more slowly varying part phi_ R1 arising
from a mean field treatment of the attractive forces. We use a generalized
linear response method to calculate the reference fluid structure, first
determining the response to the smoother part phi_ R1 of the ERF alone,
followed by the response to the harshly repulsive part. Both steps can be
carried out very accurately, as confirmed by MD simulations, and good agreement
with the structure of the full LJ fluid is found.

</DOC>
<DOC>
<DOCNO> 80857 </DOCNO>
Finite Temperature Simulations from Quantum Field Dynamics?


  We describe a Hartree ensemble method to approximately solve the Heisenberg
equations for the \phi^4 model in 1+1 dimensions. We compute the energies and
number densities of the quantum particles described by the \phi field and find
that the particles initially thermalize with a Bose-Einstein distribution for
the particle density. Gradually, however, the distribution changes towards
classical equipartition. Using suitable initial conditions quantum
thermalization is achieved much faster than the onset of this undesirable
equipartition. We also show how the numerical efficiency of our method can be
significantly improved.

</DOC>
<DOC>
<DOCNO> 120700 </DOCNO>
Discovery of mHz UV Quasiperiodic Oscillations in Hercules X-1


  Observations of the ultraviolet continuum of the X-ray binary system Her
X-1/HZ Herculis with the Space Telescope Imaging Spectrograph on the Hubble
Space Telescope show quasiperiodic oscillations (QPOs) at frequencies of 8+/-2
and 43+/-2 mHz, with rms amplitudes of 2 and 4% of the steady flux.
Observations with the Keck telescope confirm the presence of the higher
frequency QPO in the optical continuum, with a rms amplitude of 1.6+/-0.2%. The
QPOs are most prominent in the HST data near phi=0.5 (where phi=0 is the middle
of the X-ray eclipse), suggesting that they arise not in the accretion disk but
on the X-ray heated face of the companion star. We discuss scenarios in which
the companion star reprocesses oscillations in the disk which are caused by
either Keplerian rotation or a beat frequency between the neutron star spin and
Keplerian rotation at some radius in the accretion disk.

</DOC>
<DOC>
<DOCNO> 100751 </DOCNO>
Invariants of Knots and 3-manifolds from Quantum Groupoids


  We use categories of representations of finite dimensional quantum groupoids
(weak Hopf algebras) to construct ribbon and modular categories that give rise
to invariants of knots and 3-manifolds.

</DOC>
<DOC>
<DOCNO> 101208 </DOCNO>
Jordanian twists on deformed carrier subspaces


  The nontrivial subspaces with primitive coproducts are found in the deformed
universal enveloping algebras. They can form carrier spaces for additional
Jordanian twists. The latter can be used to construct sequences of twists for
algebras whose root systems contain long series of roots. The corresponding
twist for the so(5) algebra is given explicitly.

</DOC>
<DOC>
<DOCNO> 120428 </DOCNO>
FGS Astrometry with the Hubble Space Telescope


  This article describes astrometric science that can be done with the Hubble
Space Telescope Fine Guidance Sensors and presents some recent science results.
We outline how these data are modeled, acquired, and calibrated. We next show
how the astrometer, FGS 3, works as an interferometer. Finally, we present a
guide to the literature that provides additional detail for each item discussed
in the article.

</DOC>
<DOC>
<DOCNO> 120895 </DOCNO>
The Nature of Faint Submillimeter Galaxies


  We summarise the main results on the faint submillimeter (submm) galaxy
population which have come from the SCUBA Cluster Lens Survey. We detail our
current understanding of the characteristics of these submm-selected galaxies
across wavebands from X-rays to radio. After presenting the main observational
properties of this population we conclude by discussing the nature of these
distant, ultraluminous infrared galaxies and their relationship to other
high-redshift populations.

</DOC>
<DOC>
<DOCNO> 84999 </DOCNO>
Unitary dynamics of spherical null gravitating shells


  The dynamics of a thin spherically symmetric shell of zero-rest-mass matter
in its own gravitational field is studied. A form of action principle is used
that enables the reformulation of the dynamics as motion on a fixed background
manifold. A self-adjoint extension of the Hamiltonian is obtained via the group
quantization method. Operators of position and of direction of motion are
constructed. The shell is shown to avoid the singularity, to bounce and to
re-expand to that asymptotic region from which it contracted; the dynamics is,
therefore, truly unitary. If a wave packet is sufficiently narrow and/or
energetic then an essential part of it can be concentrated under its
Schwarzschild radius near the bounce point but no black hole forms. The quantum
Schwarzschild horizon is a linear combination of a black and white hole
apparent horizons rather than an event horizon.

</DOC>
<DOC>
<DOCNO> 13383 </DOCNO>
Transformation of Statistics in Fractional Quantum Hall Systems


  A Fermion to Boson transformation is accomplished by attaching to each
Fermion a tube carrying a single quantum of flux oriented opposite to the
applied magnetic field. When the mean field approximation is made in Haldane's
spherical geometry, the Fermion angular momentum l_F is replaced by
l_B=l_F-(N-1)/2. The set of allowed total angular momentum multiplets is
identical in the two different pictures. The Fermion and Boson energy spectra
in the presence of many body interactions are identical only if the
pseudopotential V (interaction energy as a function of pair angular momentum
L_12) increases as L_12(L_12+1). Similar bands of low energy states occur in
the two spectra if V increases more quickly than this.

</DOC>
<DOC>
<DOCNO> 80781 </DOCNO>
Aspects of Anomalies in Field Theory


  We discuss some formal aspects of quantum anomalies with an emphasis on the
regularization of field theory. We briefly review how ambiguities in
perturbation theory have been resolved by various regularization schemes. To
single out the true quantum anomaly among ambiguities, the combined ideas of
PCAC, soft pion limit and renormalizability were essential. As for the formal
treatment of quantum anomalies, we mainly discuss the path integral formulation
both in continuum and lattice theories. In particular, we discuss in some
detail the recent development in the treatment of chiral anomalies in lattice
gauge theory.

</DOC>
<DOC>
<DOCNO> 69957 </DOCNO>
Off-forward parton distributions and impact parameter dependence of


  The connection between parton distributions as a function of the impact
parameter and off-forward parton distributions is discussed in the limit of
vanishing skewedness parameter $\zeta$, i.e. when the off-forwardness is purely
transverse. For the $2^{nd}$ moment it is also illustrated how to relate
$\zeta\neq 0$ data to $\zeta=0$ data, which is important for experimental
measurements of these observables.

</DOC>
<DOC>
<DOCNO> 118159 </DOCNO>
NICMOS Narrow-band Infrared Photometry of TW Hya Association Stars


  We have obtained 1.64, 1.90 and 2.15 micron narrow-band images of five T
Tauri stars in the TW Hya Association (TWA) using the Near-Infrared Camera and
Multiobject Spectrometer aboard the Hubble Space Telescope. Most of the T Tauri
stars in our study show evidence of absorption by H2O vapor in their
atmospheres; in addition, the low-mass brown dwarf candidate, TWA 5B, is
brighter at 1.9 microns than predicted by cool star models that include the
effects of H2O vapor but neglect dust. We conclude that the effect of
atmospheric dust on the opacity is important at 1.9 microns for TWA 5B, the
coolest object in our sample. The available evidence suggests that the TWA is
5-15 MY old. Comparison of the colors of TWA 5B with theoretical magnitudes as
a function of age and mass then confirms previous claims that TWA 5B is
substellar with a mass in the range 0.02-0.03 solar masses. The accurate
single-epoch astrometry of the relative positions and separation of TWA 5A and
TWA 5B reported here should permit the direct measurement of the orbital motion
of TWA 5B within only a few years.

</DOC>
<DOC>
<DOCNO> 69585 </DOCNO>
Single Stop Production at Hadron Colliders


  We analyze the production of a single top squark at hadron colliders:
ppbar/pp -> \tilde{t}_1 + X. The total cross sections and the transverse
momentum distributions are presented in next-to-leading order QCD. The
higher-order corrections render the predictions theoretically stable with
respect to variations of the factorization and renormalization scales. The
transverse momentum distribution is resummed to estimate effects of the small
transverse momentum regime on possible analyses. Since the corrections increase
the cross sections and reduce the theoretical uncertainty, the discovery range
for these particles is extended in the refined analysis.

</DOC>
<DOC>
<DOCNO> 101180 </DOCNO>
Modelling and analysis of fractional-order regulated systems in the


  In this paper we present the mathematical description and analysis of a
fractional-order regulated system in the state space. A little historical
background of our results in the analysis and synthesis of the fractional-order
dynamical regulated systems is given. The methods and results of simulations of
the fractional-order system described by a state space equation equivalent to
three-member fractional-order differential equation with a fractional-order
$PD^{\delta}$ regulator are then presented. The possibility of investigating
the stability of such systems is also considered.

</DOC>
<DOC>
<DOCNO> 99294 </DOCNO>
Endpoint multiplier theorems of Marcinkiewicz type


  We establish sharp (H^1, L^{1,q}) and local (L \log^r L, L^{1,q}) mapping
properties for rough one-dimensional multipliers. In particular, we show that
the multipliers in the Marcinkiewicz multiplier theorem map H^1 to L^{1,\infty}
and L \log^{1/2} L to L^{1,\infty}, and that these estimates are sharp.

</DOC>
<DOC>
<DOCNO> 100004 </DOCNO>
Second-order linear differential equations with two irregular singular


  For a second-order linear differential equation with two irregular singular
points of rank three, multiple Laplace-type contour integral solutions are
considered. An explicit formula in terms of the Stokes multipliers is derived
for the characteristic exponent of the multiplicative solutions. The Stokes
multipliers are represented by converging series with terms for which limit
formulas as well as more detailed asymptotic expansions are available. Here
certain new, recursively known coefficients enter, which are closely related to
but different from the coefficients of the formal solutions at one of the
irregular singular points of the differential equation. The coefficients of the
formal solutions then appear as finite sums over subsets of the new
coefficients. As a by-product, the leading exponential terms of the asymptotic
behaviour of the late coefficients of the formal solutions are given, and this
is a concrete example of the structural results obtained by Immink in a more
general setting. The formulas displayed in this paper are not of merely
theoretical interest, but they also are complete in the sense that they could
be (and have been) implemented for computing accurate numerical values of the
characteristic exponent, although the computational load is not small and
increases with the rank of the singular point under consideration.

</DOC>
<DOC>
<DOCNO> 152128 </DOCNO>
D-branes in non-tachyonic 0B orientifolds


  We determine all D-branes in the non-tachyonic 0'B orientifold, examine their
world-volume anomalies and study orbifold compactifications. We find that the
spectrum of the D-branes contains chiral fermions in the symmetric,
antisymmetric and fundamental representations of (unitary) gauge groups on the
branes. The cancellation of the world-volume anomalies requires Wess-Zumino
terms which we determine explicitly. We examine a non-tachyonic
compactification to 9D whose closed part interpolates between 0B and IIB and
revisit compactifications on orbifolds. The D3-brane allows to conjecture, via
the AdS/CFT correspondence, a supergravity dual to a non-supersymmetric and
infrared-free gauge theory. The D-string gives hints concerning the S-dual of
the 0'B orientifold.

</DOC>
<DOC>
<DOCNO> 12448 </DOCNO>
A compromised arrow of time


  The second law of thermodynamics - the usual statement of the arrow of time -
has been called the most fundamental law of physics. It is thus difficult to
conceive that a single dynamical system could contain subsystems, in
significant mutual contact, possessing opposite thermodynamic arrows of time.
By examining cosmological justification for the usual arrow it is found that a
consistent way to establish such justification is by giving symmetric boundary
conditions at two (cosmologically remote) times and seeking directional
behavior in between. Once this has been demonstrated, it is seen that entropy
increase can be reversed and that the usual arrow is less totalitarian than
previously believed. In the same vein, other boundary conditions, modeling
shorter periods in the evolution of the cosmos, can be found that allow the
simultaneous existence of two thermodynamic arrows, notwithstanding moderate
interaction between the systems possessing those arrows. Physical consequences
of the existence and detection of opposite-arrow regions are also considered.

</DOC>
<DOC>
<DOCNO> 69769 </DOCNO>
Multi-field fermionic preheating


  Fermion creation during preheating in the presence of multiple scalar fields
exhibits a range of interesting behaviour relevant to estimating post-inflation
gravitino abundances. We present non-perturbative analysis of this phenomenon
over a 6-dimensional parameter space in an expanding background paying
particular attention to the interplay between instant and direct fermion
preheating. In the broad resonance regime we find that instant fermion
production is sensitive to suppression of the long wavelength scalar field
modes during inflation. Further, the standard scenario of resonant fermionic
preheating through inflaton decay can be significantly modified by instant
preheating, and may even lead to a decrease in the number of fermions produced.
We explicitly include the effects of metric perturbations and demonstrate that
they are important at small coupling but not at strong coupling, due to the
rapid saturation of the Pauli bound.

</DOC>
<DOC>
<DOCNO> 151658 </DOCNO>
General Low Energy Dynamics of Supersymmetric Monopoles


  We derive general low energy dynamics of monopoles and dyons in N=2 and N=4
supersymmetric Yang-Mills theories by utilising a collective coordinate
expansion. The resulting new kind of supersymmetric quantum mechanics
incorporates the effects of multiple Higgs fields, both in the N=2 vector
multiplet and hypermultiplets, having non-vanishing expectation values.

</DOC>
<DOC>
<DOCNO> 119735 </DOCNO>
The Dark Matter Telescope


  Weak gravitational lensing enables direct reconstruction of dark matter maps
over cosmologically significant volumes. This research is currently
telescope-limited. The Dark Matter Telescope (DMT) is a proposed 8.4 m
telescope with a 3 degree field of view, with an etendue of 260 $(m.
degree)^2$, ten times greater than any other current or planned telescope. With
its large etendue and dedicated observational mode, the DMT fills a nearly
unexplored region of parameter space and enables projects that would take
decades on current facilities. The DMT will be able to reach 10-sigma limiting
magnitudes of 27-28 magnitude in the wavelength range .3 - 1 um over a 7 square
degree field in 3 nights of dark time. Here we review its unique weak lensing
cosmology capabilities and the design that enables those capabilities.

</DOC>
<DOC>
<DOCNO> 117379 </DOCNO>
The oxygen abundance deficiency in irregular galaxies


  The observed oxygen abundances in a number of irregular galaxies have been
compared with predictions of the closed-box model of chemical and photometric
evolution of galaxies. Oxygen is found to be deficient with respect to the
predicted abundances. This is an indicator in favor of loss of heavy elements
via galactic winds or/and of infall of low--abundance gas onto the galaxy.
   The oxygen abundance deficiency observed within the optical edge of a galaxy
cannot be explained by mixing with the gas envelope observed outside the
optical limit. We confirm the widespread idea that a significant part of the
heavy elements is ejected by irregular galaxies in the intergalactic medium.

</DOC>
<DOC>
<DOCNO> 13639 </DOCNO>
Scaling properties of scale-free evolving networks: Continuous approach


  Scaling behavior of scale-free evolving networks arising in communications,
citations, collaborations, etc. areas is studied. We derive universal scaling
relations describing properties of such networks and indicate limits of their
validity. We show that main properties of scale-free evolving networks may be
described in frames of a simple continuous approach. The simplest models of
networks, which growth is determined by a mechanism of preferential linking,
are used. We consider different forms of this preference and demonstrate that
the range of types of preference linking producing scale-free networks is wide.
We obtain also scaling relations for networks with nonlinear, accelerating
growth and describe temporal evolution of arising distributions. Size-effects -
cut-offs of these distributions - implement restrictions for observation of
power-law dependences. The main characteristic of interest is so-called degree
distribution, i.e., distribution of a number of connections of nodes. A scaling
form of the distribution of links between pairs of individual nodes for the
growing network of citations is also studied. We describe effects that produce
difference of nodes. ``Aging'' of nodes changes exponents of distributions.
Appearence of a single ``strong'' node changes dramatically the degree
distribution of a network. If its strength exceeds some threshold value, the
strong node captures a finite part of all links of a network. We show that
permanent random damage of a growing scale-free network - permanent deleting of
some links - change radically values of the scaling exponents. We describe the
arising rich phase diagram. Results of other types of permanent damage are
described.

</DOC>
<DOC>
<DOCNO> 8897 </DOCNO>
Exact results for some Madelung type constants in the finite-size


  A general formula is obtained from which the madelung type constant: $$
C(d|\nu)=\int_0^\infty dx x^{d/2-\nu-1}[(\sum_{l=-\infty}^\infty
e^{-xl^2})^d-1-(\frac\pi x)^{d/2}] $$ extensively used in the finite-size
scaling theory is computed analytically for some particular cases of the
parameters $d$ and $\nu$. By adjusting these parameters one can obtain
different physical situations corresponding to different geometries and
magnitudes of the interparticle interaction.

</DOC>
<DOC>
<DOCNO> 122652 </DOCNO>
Simultaneous intensive photometry and high resolution spectroscopy of


  We discuss here the pulsation properties of the $\delta$ Scuti star BV
Circini on the basis of data obtained during a simultaneous photometric and
spectroscopic campaign in 1996 and a spectroscopic one in 1998, and taking also
advantage of the previous photometric observations by Kurtz (1981). Nine
pulsation modes were detected from photometry and thirteen from spectroscopy;
five of them are in common to both techniques. The spectroscopic data give
ample evidence of dramatic amplitude variations in some modes, in particular
the strongest spectroscopic mode in 1998 was not detectable in 1996 data. The
two dominant photometric modes (6.33 and 7.89 c\d) are observed on both
seasons. The typing of the modes was performed by means of a simultaneous model
fit of line profile and light variations. The 6.33 c\d photometric term is
probably the fundamental radial mode, while the 7.89 c\d is a nonradial mode
with mi different than 0. There are six high-degree prograde modes with an
azimuthal order m ranging from -12 to -14, and also a retrograde mode with m~7.
These modes combined with the identification of the 6.33 c\d mode allowed us to
estimate i~60 deg for the value of the inclination of the rotation axis. An
accurate evaluation of the main stellar physical parameters is also proposed as
a result of the pulsational analysis.

</DOC>
<DOC>
<DOCNO> 11304 </DOCNO>
Phonon anomalies due to strong electronic correlations in layered


  We show how the coupling between the phonons and electrons in a strongly
correlated metal can result in phonon frequencies which have a non-monotonic
temperature dependence. Dynamical mean-field theory is used to study the
Hubbard-Holstein model that describes the \kappa-(BEDT-TTF)_2 X family of
superconducting molecular crystals. The crossover with increasing temperature
from a Fermi liquid to a bad metal produces phonon anomalies that are
consistent with recent Raman scattering and acoustic experiments.

</DOC>
<DOC>
<DOCNO> 99908 </DOCNO>
Discrete spectral symmetries of low-dimensional differential operators


  Euler-Darboux-Backlund and Laplace transformations are considered for the
one- and two-dimensional Schrodinger operators. Their discrete analogs are
constructed and generalized for the multidimensional lattices and two-manifolds
with special "black-white" triangulations. Nonstandard generalizations of the
connections and curvature are constructed for the simplicial complexes. Exactly
solvable 2D Schrodinger operators with nonstandard spectral properties are
constructed in the continuous and discrete cases using Laplace chains with
different restrictions.

</DOC>
<DOC>
<DOCNO> 72151 </DOCNO>
Lifetime difference of $B_s$ mesons - Theory status


  We give an update on the lifetime difference of $B_s$ mesons which accounts
for recent lattice bag parameter results, and obtain
$(\Delta\Gamma/\Gamma)_{B_s}=(9.3^{+3.4}_{-4.6})%$. We then review the current
theoretical uncertainties and conclude with a pessimistic perspective on
further improvements.

</DOC>
<DOC>
<DOCNO> 7715 </DOCNO>
Semiclassical description of electronic supershells in simple metal


  A semiclassical approach for calculating shell effects, that has been used in
atomic and plasma physics, is applied to describe the electronic supershells in
metal clusters. Using the spherical jellium model we give the analytical
expression for the oscillating part of the binding energy of electrons as an
explicit sum of contributions from supershells with quantum numbers 2n_r+l,
3n_r+l, 4n_r+l, ... This expression is written in terms of the classical
characteristics of the motion of an electron with the Fermi energy in a
self-consistent potential. The conditions under which a new supershell appears
and the relative contribution of this shell are studied as a function of the
cluster size and form of the potential. Specific calculations are performed for
a square well.

</DOC>
<DOC>
<DOCNO> 70250 </DOCNO>
Particle and Astrophysics Aspects of Ultrahigh Energy Cosmic Rays


  The origin of cosmic rays is one of the major unresolved astrophysical
questions. In particular, the highest energy cosmic rays observed possess
macroscopic energies and their origin is likely to be associated with the most
energetic processes in the Universe. Their existence triggered a flurry of
theoretical explanations ranging from conventional shock acceleration to
particle physics beyond the Standard Model and processes taking place at the
earliest moments of our Universe. Furthermore, many new experimental activities
promise a strong increase of statistics at the highest energies and a
combination with $\gamma-$ray and neutrino astrophysics will put strong
constraints on these theoretical models. Detailed Monte Carlo simulations
indicate that charged ultra-high energy cosmic rays can also be used as probes
of large scale magnetic fields whose origin may open another window into the
very early Universe. We give an overview over this quickly evolving research
field.

</DOC>
<DOC>
<DOCNO> 9857 </DOCNO>
Decoupling of Layers in the Three-dimensional Abelian Higgs Model


  The Abelian Higgs model with anisotropic couplings in 2+1 dimensions is
studied in both the compact and non-compact formulations. Decoupling of the
space-like planes takes place in the extreme anisotropic limit, so charged
particles and gauge fields are presumably localized within these planes. The
behaviour of the model under the influence of an external magnetic field is
examined in the compact case and yields further characterization of the phases.

</DOC>
<DOC>
<DOCNO> 14174 </DOCNO>
Finite Temperature Time-Dependent Effective Theory for the Phase Field


  We derive finite temperature time-dependent effective actions for the phase
of the pairing field, which are appropriate for a 2D electron system with both
non-retarded d- and s-wave attraction. As for s-wave pairing the d-wave
effective action contains terms with Landau damping, but their structure
appears to be different from the s-wave case due to the fact that the Landau
damping is determined by the quasiparticle group velocity v_{g}, which for
d-wave pairing does not have the same direction as the non-interacting Fermi
velocity v_{F}. We show that for d-wave pairing the Landau term has a linear
low temperature dependence and in contrast to the s-wave case are important for
all finite temperatures. A possible experimental observation of the phase
excitations is discussed.

</DOC>
<DOC>
<DOCNO> 8639 </DOCNO>
An NMR-based nanostructure switch for quantum logic


  We propose a nanostructure switch based on nuclear magnetic resonance (NMR)
which offers reliable quantum gate operation, an essential ingredient for
building a quantum computer. The nuclear resonance is controlled by the magic
number transitions of a few-electron quantum dot in an external magnetic field.

</DOC>
<DOC>
<DOCNO> 69717 </DOCNO>
Chiral Extrapolation, Renormalization, and the Viability of the Quark


  The relationship of the quark model to the known chiral properties of QCD is
a longstanding problem in the interpretation of low energy QCD. In particular,
how can the pion be viewed as both a collective Goldstone boson quasiparticle
and as a valence quark antiquark bound state where universal hyperfine
interactions govern spin splittings in the same way as in the heavy quark
systems. We address this issue in a simplified model which; however, reproduces
all features of QCD relevant to this problem. A comparison of the many-body
solution to our model and the constituent quark model demonstrates that the
quark model is sufficiently flexible to describe meson hyperfine splitting
provided proper renormalization conditions and correct degrees of freedom are
employed consistently.

</DOC>
<DOC>
<DOCNO> 11487 </DOCNO>
Orbital liquid in three dimensional Mott insulator: $LaTiO_3$


  We present a theory of spin and orbital states in Mott insulator $LaTiO_3$.
The spin-orbital superexchange interaction between $d^1(t_{2g})$ ions in cubic
crystal suffers from a pathological degeneracy of orbital states at classical
level. Quantum effects remove this degeneracy and result in the formation of
the coherent ground state, in which the orbital moment of $t_{2g}$ level is
fully quenched. We find a finite gap for orbital excitations. Such a disordered
state of local degrees of freedom on unfrustrated, simple cubic lattice is
highly unusual. Orbital liquid state naturally explains observed anomalies of
$LaTiO_3$.

</DOC>
<DOC>
<DOCNO> 84315 </DOCNO>
Integrating factors for second order ODEs


  A systematic algorithm for building integrating factors of the form mu(x,y),
mu(x,y') or mu(y,y') for second order ODEs is presented. The algorithm can
determine the existence and explicit form of the integrating factors themselves
without solving any differential equations, except for a linear ODE in one
subcase of the mu(x,y) problem. Examples of ODEs not having point symmetries
are shown to be solvable using this algorithm. The scheme was implemented in
Maple, in the framework of the "ODEtools" package and its ODE-solver. A
comparison between this implementation and other computer algebra ODE-solvers
in tackling non-linear examples from Kamke's book is shown.

</DOC>
<DOC>
<DOCNO> 8276 </DOCNO>
Successive opening of the Fermi surface in doped N-leg Hubbard ladders


  We study the effect of doping away from half-filling in weakly (but finitely)
interacting N-leg Hubbard ladders using renormalization group and bosonization
techniques. For a small on-site repulsion U, the N-leg Hubbard ladders are
equivalent to a N-band model, where at half-filling the Fermi velocities are
v_{1}=v_{N}<v_{2}=v_{N-1}<... We then obtain a hierarchy of energy-scales,
where the band pairs (j,N+1-j) are successively frozen out. The low-energy
Hamiltonian is then the sum of N/2 (or (N-1)/2 for N odd) two-leg ladder
Hamiltonians without gapless excitations (plus a single chain for N odd with
one gapless spin mode), similar to the N-leg Heisenberg spin-ladders. The
energy-scales lead to a hierarchy of gaps. Upon doping away from half-filling,
the holes enter first the band(s) with the smallest gap: For odd N, the holes
enter first the nonbonding band (N+1)/2 and the phase is a Luttinger liquid,
while for even N, the holes enter first the band pair (N/2,N/2+1) and the phase
is a Luther-Emery liquid, similar to numerical treatments of the t-J model,
i.e., at and close to half-filling, the phases of the Hubbard ladders for small
and large U are the same. For increasing doping, hole-pairs subsequently enter
at critical dopings the other band pairs (j,N+1-j) (accompanied by a diverging
compressibility): The Fermi surface is successively opened by doping, starting
near the wave vector (pi/2,pi/2). Explicit calculations are given for the cases
N=3,4.

</DOC>
<DOC>
<DOCNO> 70313 </DOCNO>
Renormalons as dilatation modes in the functional space


  There are two sources of the factorial large-order behavior of a typical
perturbative series. First, the number of the different Feynman diagrams may be
large; second, there are abnormally large diagrams known as renormalons. It is
well known that the large combinatorial number of diagrams is described by
instanton-type solutions of the classical equations. We demonstrate that from
the functional-integral viewpoint the renormalons do not correspond to a
particular configuration but manifest themselves as dilatation modes in the
functional space.

</DOC>
<DOC>
<DOCNO> 68504 </DOCNO>
The (in)stability of global monopoles revisited


  We analyse the stability of global O(3) monopoles in the infinite cut-off (or
scalar mass) limit. We obtain the perturbation equations and prove that the
spherically symmetric solution is classically stable (or neutrally stable) to
axially symmetric square integrable or power-law decay perturbations. Moreover
we show that, in spite of the existence of a conserved topological charge, the
energy barrier between the monopole and the vacuum is finite even in the limit
where the cut-off is taken to infinity. This feature is specific of global
monopoles and independent of the details of the scalar potential.

</DOC>
<DOC>
<DOCNO> 116726 </DOCNO>
Photon echo signature of vibrational cat states created by femtosecond


  A pair of coherent femtosecond pulse excitations applied to a molecule with
strong electron-phonon coupling creates a coherent superposition of a low
momentum and a high momentum wavepacket in the vibrational states of both the
excited state and the ground state of the coherent transition. As the excited
state is accelerated further, interference between the high momentum ground
state contribution and the low momentum excited state contribution causes a
photon echo. This photon echo is a direct consequence of quantum interference
between separate vibrational trajectories and can therefore provide
experimental evidence of the non-classical properties of molecular vibrations.

</DOC>
<DOC>
<DOCNO> 122620 </DOCNO>
Where is the [O III]4363 emitting region in active galactic nuclei?


  The emission-line flux ratio of [O III]4363/[O III]5007 (R_OIII)is a useful
diagnostic for the ionization mechanism and physical properties of
emission-line regions in active galactic nuclei (AGNs). However, it is known
that simple photoionization models underpredict the [O III]4363 intensity,
being inconsistent with observations. In this paper, we report on several
pieces of evidence that a large fraction of the [O III]4363 emission arises
from the dense gas obscured by putative tori: (1) the visibility of high-R_OIII
regions is correlated to that of broad-line regions, (2) higher-R_OIII objects
show hotter mid-infrared colors, (3) higher-R_OIII objects show stronger
highly-ionized emission lines such as [Fe VII]6087 and [Fe X]6374, and (4)
higher-R_OIII objects have broader line width of [O III]4363 normalized by that
of [O III]5007. To estimate how such a dense component contributes to the total
emission-line flux, dual-component photoionization model calculations are
performed. It is shown that the observed values of R_OIII of type 1 AGNs may be
explained by introducing a 5% - 20% contribution from the dense component while
those of type 2 AGNs may be explained by introducing a 0% - 2% contribution. We
also discuss the [O III]4363 emitting regions in LINERs in the framework of our
dual-component model.

</DOC>
<DOC>
<DOCNO> 83117 </DOCNO>
Probabilistic Default Reasoning with Conditional Constraints


  We propose a combination of probabilistic reasoning from conditional
constraints with approaches to default reasoning from conditional knowledge
bases. In detail, we generalize the notions of Pearl's entailment in system Z,
Lehmann's lexicographic entailment, and Geffner's conditional entailment to
conditional constraints. We give some examples that show that the new notions
of z-, lexicographic, and conditional entailment have similar properties like
their classical counterparts. Moreover, we show that the new notions of z-,
lexicographic, and conditional entailment are proper generalizations of both
their classical counterparts and the classical notion of logical entailment for
conditional constraints.

</DOC>
<DOC>
<DOCNO> 99936 </DOCNO>
Reconstruction of Gray-scale Images


  Reconstruction of images corrupted by noise is an important problem in Image
Analysis. In the standard Bayesian approach the unknown original image is
assumed to be a realization of a Markov random field on a finite two
dimensional finite region. This image is degraded by some noise, which acts
independently in each site of and has the same distribution on all sites. The
reconstructed image is the maximum a posteriori (MAP) estimator. When the
number of colors is bigger than two the standard a priori measure is the Potts
model, but with this choice reconstruction algorithms need exponential growing
time in the number of pixels. We propose a different a priori measure that
allows to compute the MAP estimator in polinomial time. The algorithm binary
decomposes the intensity of each color and reconstructs each component,
reducing the problem to the computation of the two-color MAP estimator. The
latter is done in polinomial time solving a min-cut max-flow problem in a
binary graph as proposed by Greig, Porteous and Seheult (1989).

</DOC>
<DOC>
<DOCNO> 10138 </DOCNO>
Fermionic Quantum Gravity


  We study the statistical mechanics of random surfaces generated by NxN
one-matrix integrals over anti-commuting variables. These Grassmann-valued
matrix models are shown to be equivalent to NxN unitary versions of generalized
Penner matrix models. We explicitly solve for the combinatorics of 't Hooft
diagrams of the matrix integral and develop an orthogonal polynomial
formulation of the statistical theory. An examination of the large N and double
scaling limits of the theory shows that the genus expansion is a Borel summable
alternating series which otherwise coincides with two-dimensional quantum
gravity in the continuum limit. We demonstrate that the partition functions of
these matrix models belong to the relativistic Toda chain integrable hierarchy.
The corresponding string equations and Virasoro constraints are derived and
used to analyse the generalized KdV flow structure of the continuum limit.

</DOC>
<DOC>
<DOCNO> 9565 </DOCNO>
Universal features of the order-parameter fluctuations : reversible and


  We discuss the universal scaling laws of order parameter fluctuations in any
system in which the second-order critical behaviour can be identified. These
scaling laws can be derived rigorously for equilibrium systems when combined
with the finite-size scaling analysis. The relation between order parameter,
criticality and scaling law of fluctuations has been established and the
connexion between the scaling function and the critical exponents has been
found. We give examples in out-of-equilibrium aggregation models such as the
Smoluchowski kinetic equations, or of at-equilibrium Ising and percolation
models.

</DOC>
<DOC>
<DOCNO> 84199 </DOCNO>
Local and global existence theorems for the Einstein equations


  This article is a guide to the literature on existence theorems for the
Einstein equations which also draws attention to open problems in the field.
The local in time Cauchy problem, which is relatively well understood, is
treated first. Next global results for solutions with symmetry are discussed. A
selection of results from Newtonian theory and special relativity which offer
useful comparisons is presented. This is followed by a survey of global results
in the case of small data and results on constructing spacetimes with given
singularity structure. The article ends with some miscellaneous topics
connected with the main theme.

</DOC>
<DOC>
<DOCNO> 117401 </DOCNO>
Neutron Star Mass Determinations


  I review attempts made to determine the properties of neutron stars. The
focus is on the maximum mass that a neutron star can have, or, conversely, the
minimum mass required for the formation of a black hole. There appears to be
only one neutron star for which there is strong evidence that its mass is above
the canonical 1.4 solar masses, viz., Vela X-1, for which a mass close to 1.9
solar masses is found. Prospects for progress appear brightest for studies of
systems in which the neutron star should have accreted substantial amounts of
matter.

</DOC>
<DOC>
<DOCNO> 85360 </DOCNO>
Operator ordering for generally covariant systems


  The constraint operators belonging to a generally covariant system are found
out within the framework of the BRST formalism. The result embraces quadratic
Hamiltonian constraints whose potential can be factorized as a never null
function times a gauge invariant function. The building of the inner product
between physical states is analyzed for systems featuring either intrinsic or
extrinsic time.

</DOC>
<DOC>
<DOCNO> 117742 </DOCNO>
Power filtration of CMB observational data


  We propose a power filter Gp for linear reconstruction of the CMB signal from
observational maps. This Gp filter preserves the power spectrum of the CMB
signal in contrast to the Wiener filter which diminishes the power spectrum of
the reconstructed CMB signal. We demonstrate how peak statistics and a cluster
analysis can be used to estimate the probability of the presence of a CMB
signal in observational records. The efficiency of the Gp filter is
demonstrated on a toy model of an observational record consisting of a CMB
signal and noise in the form of foreground point sources.

</DOC>
<DOC>
<DOCNO> 85588 </DOCNO>
General approach to the study of vacuum space-times with an isometry


  In vacuum space-times the exterior derivative of a Killing vector field is a
2-form (named here as the Papapetrou field) that satisfies Maxwell's equations
without electromagnetic sources. In this paper, using the algebraic structure
of the Papapetrou field, we will set up a new formalism for the study of vacuum
space-times with an isometry, which is suitable to investigate the connections
between the isometry and the Petrov type of the space-time. This approach has
some advantages, among them, it leads to a new classification of these
space-times and the integrability conditions provide expressions that determine
completely the Weyl curvature. These facts make the formalism useful for
application to any problem or situation with an isometry and requiring the
knowledge of the curvature.

</DOC>
<DOC>
<DOCNO> 119228 </DOCNO>
High Energy Physics and Quintessence


  It is shown that any realistic model of quintessence should be based on
Supergravity (SUGRA) since the value of the quintessence field on the attractor
is approximately the Planck mass. Under very general assumptions, the typical
shape of a SUGRA tracking potential is derived. Cosmological implications are
investigated. In particular, it is demonstrated that, generically, the equation
of state parameter is driven to a value close to -1 in agreement with recent
observations.

</DOC>
<DOC>
<DOCNO> 118690 </DOCNO>
Photometric and kinematic studies of open star clusters. II. NGC 1960 (M


  We present CCD photometry and proper motion studies of the two open star
clusters NGC 1960 (M 36) and NGC 2194. Fitting isochrones to the colour
magnitude diagrams, for NGC 1960 we found an age of t=16 Myr and a distance of
roughly d=1300 pc and for NGC 2194 t=550 Myr and d=2900 pc, respectively. We
combined membership determination by proper motions and statistical field star
subtraction to derive the initial mass function of the clusters and found
slopes of Gamma=-1.23 +/- 0.17 for NGC 1960 and Gamma=-1.33 +/- 0.29 for NGC
2194. Compared to other IMF studies of the intermediate mass range, these
values indicate shallow mass functions.

</DOC>
<DOC>
<DOCNO> 84592 </DOCNO>
The Energy and Time


  The energy and time variables of the elementary classical dynamical systems
are described geometrically, as canonically conjugate coordinates of an
extended phase-space. It is shown that the Galilei action of the inertial
equivalence group on this space is canonical, but not Hamiltonian equivariant.
Although it has no effect at classical level, the lack of equivariance makes
the Galilei action inconsistent with the canonical quantization. A Hamiltonian
equivariant action can be obtained by assuming that the inertial parameter in
the extended phase-space is quasi-isotropic. This condition leads naturally to
the Lorentz transformations between moving frames as a particular case of
symplectic transformations. The limit speed appears as a constant factor
relating the two additional canonical coordinates to the energy and time. Its
value is identified with the speed of light by using the relationship between
the electromagnetic potentials and the symplectic form of the extended
phase-space.

</DOC>
<DOC>
<DOCNO> 116607 </DOCNO>
On the geometry of plasma reactor


  It is presented the concept of controled nuclear synthesis in top of cone
formed by rotational dynamic flow of low-temperature plasma.

</DOC>
<DOC>
<DOCNO> 71938 </DOCNO>
Compatibility of various approaches to heavy-quark fragmentation


  We find that the definition of the heavy-quark fragmentation function given
by Jaffe and Randall differs by a factor of the longitudinal-momentum fraction
z from the standard Collins-Soper definition. Once this factor is taken into
account, the explicit calculation of Braaten et al. is found to be in agreement
with the general analysis of Jaffe and Randall. We also examine the model of
Peterson et al. for heavy-quark fragmentation and find that the quoted values
of the width and of the value of $z$ at the maximum are in error. The corrected
values are in agreement with the analysis of Jaffe and Randall.

</DOC>
<DOC>
<DOCNO> 121920 </DOCNO>
The Cosmic Electron Background in Low Energy IACTs. Effect of the


  A new generation of low threshold Imaging Atmospheric Cherenkov Telescopes
(IACTs) may reach gamma-ray energies about 10 GeV with high sensitivities and
very large collection areas. At these low energies cosmic electrons
significantly contribute to the telescope background and are in principle
indistinguishable from gamma-rays. In this paper we estimate the electron
background expected for two configurations of the low energy IACT MAGIC. We
discuss in particular the reduction of the background caused by the geomagnetic
field at different locations on the Earth's surface.

</DOC>
<DOC>
<DOCNO> 123104 </DOCNO>
Irregular Magnetic Fields in Interstellar Clouds and the Linear


  Calculations are performed for the linear polarization of starlight due to
extinction by aligned dust grains when the starlight traverses a medium with
irregular magnetic fields. This medium is intended to represent the optically
thick components of interstellar clouds which are observed to make little, if
any, contribution to the polarization of starlight. In agreement with the
observations, we find that the polarization properties of the starlight---the
average fractional polarization and the dispersion in position angles---can be
essentially unchanged. For this, the rms of the irregular component must be
greater than the average magnetic field, which in turn tends to imply that the
turbulent velocities in these interstellar clouds are super-Alfvenic.

</DOC>
<DOC>
<DOCNO> 8210 </DOCNO>
The diagonalization of quantum field Hamiltonians


  We introduce a new diagonalization method called quasi-sparse eigenvector
diagonalization which finds the most important basis vectors of the low energy
eigenstates of a quantum Hamiltonian. It can operate using any basis, either
orthogonal or non-orthogonal, and any sparse Hamiltonian, either Hermitian,
non-Hermitian, finite-dimensional, or infinite-dimensional. The method is part
of a new computational approach which combines both diagonalization and Monte
Carlo techniques.

</DOC>
<DOC>
<DOCNO> 40086 </DOCNO>
Multiplicities of pizero, eta, Kzero and of charged particles in quark


  We compared the multiplicities of pizero, eta, Kzero and of charged particles
in quark and gluon jets in 3-jet events, as measured by the OPAL experiment at
LEP. The comparisons were performed for distributions unfolded to 100% pure
quark and gluon jets, at an effective scale Qjet which took into account
topological dependences of the 3-jet environment. The ratio of particle
multiplicity in gluon jets to that in quark jets as a function of Qjet for
pizero, eta and Kzero was found to be independent of the particle species. This
is consistent with the QCD prediction that the observed enhancement in the mean
particle rate in gluon jets with respect to quark jets should be independent of
particle species. In contrast to some theoretical predictions and previous
observations, we observed no evidence for an enhancement of eta meson
production in gluon jets with respect to quark jets, beyond that observed for
charged particles. We measured the ratio of the slope of the average charged
particle multiplicity in gluon jets to that in quark jets, C, and we compared
it to a next-to-next-to-next-to leading order calculation. Our result,
C=2.27+-0.20(stat+syst),is about one standard deviation higher than the
perturbative prediction.

</DOC>
<DOC>
<DOCNO> 12731 </DOCNO>
Glassy systems under time-dependent driving forces: application to slow


  We study the dynamics of a glassy model with infinite range interactions
externally driven by an oscillatory force. We find a well-defined transition in
the (Temperature-Amplitude-Frequency) phase diagram between (i) a `glassy'
state characterized by the slow relaxation of one-time quantities, aging in
two-time quantities and a modification of the equilibrium
fluctuation-dissipation relation; and (ii) a `liquid' state with a finite
relaxation time. In the glassy phase, the degrees of freedom governing the slow
relaxation are thermalized to an effective temperature. Using Monte-Carlo
simulations, we investigate the effect of trapping regions in phase space on
the driven dynamics. We find that it alternates between periods of rapid motion
and periods of trapping. These results confirm the strong analogies between the
slow granular rheology and the dynamics of glasses. They also provide a
theoretical underpinning to earlier attempts to present a thermodynamic
description of moderately driven granular materials.

</DOC>
<DOC>
<DOCNO> 12329 </DOCNO>
Phase behavior and material properties of hollow nanoparticles


  Effective pair potentials for hollow nanoparticles like the ones made from
carbon (fullerenes) or metal dichalcogenides (inorganic fullerenes) consist of
a hard core repulsion and a deep, but short-ranged, van der Waals attraction.
We investigate them for single- and multi-walled nanoparticles and show that in
both cases, in the limit of large radii the interaction range scales inversely
with the radius, $R$, while the well depth scales linearly with $R$. We predict
the values of the radius $R$ and the wall thickness $h$ at which the gas-liquid
coexistence disappears from the phase diagram. We also discuss unusual material
properties of the solid, which include a large heat of sublimation and a small
surface energy.

</DOC>
<DOC>
<DOCNO> 70592 </DOCNO>
Self-Tuning Dark Energy in Brane World Cosmology


  Recently, the self-tuning mechanism of cancellation of vacuum energy has been
proposed in which our universe is a flat 3-brane in a 5-dimensional spacetime.
In this letter, the self-tuning mechanism of dark energy is proposed by
considering the cosmological matter in the brane world. In our model, the bulk
scalar field takes the role of the dark energy and its value is slowly varying
in time. The claim is that even if the enormous amount of vacuum energy exists
on the brane we can adjust the present value of the dark energy to be
consistent with the current observations. In this self-tuning mechanism, the
existence of the constant of integration associated with the bulk scalar is
crucial.

</DOC>
<DOC>
<DOCNO> 71208 </DOCNO>
Coherent particle production in collisions of relativistic nuclei


  Here we give the results of our study of features of dense groups, or spikes,
of particles produced in Mg-Mg and C-Cu collisions at, respectively, 4.3 and
4.5 GeV/c/nucleon aimed to search for a coherent, Cerenkov-like, mechanism of
hadroproduction. We investigate the distributions of spike centers and, for
Mg-Mg interactions, the energy spectra of negatively charged particles in
spikes. The spike-center distributions are obtained to exhibit the structure
expected from coherent gluon-jet emission dynamics. This structure is similar
in both cases considered, namely for all charged and negatively charged
particles, and is also similar to that observed recently for
all-charged-particle spikes in hadronic interactions. The energy distribution
within spikes is found to have a significant peak over the inclusive
background, while the inclusive spectrum shows exponential decrease with two
characteristic values of average kinetic energy. The value of the peak energy
and its width are in a good agreement with those expected for pions produced in
a nuclear medium in the framework of the Cerenkov quantum approach. The peak
energy obtained is consistent with the value of the cross-section maximum
observed in coincidence nucleon-nucleus interaction experiments.

</DOC>
<DOC>
<DOCNO> 117843 </DOCNO>
Linear and non-linear theory of a parametric instability of hydrodynamic


  We consider the stability of warping modes in Keplerian discs. We find them
to be parametrically unstable using two lines of attack, one based on
three-mode couplings and the other on Floquet theory. We confirm the existence
of the instability, and investigate its nonlinear development in three
dimensions, via numerical experiment. The most rapidly growing non-axisymmetric
disturbances are the most nearly axisymmetric (low m) ones. Finally, we offer a
simple, somewhat speculative model for the interaction of the parametric
instability with the warp. We apply this model to the masing disc in NGC 4258
and show that, provided the warp is not forced too strongly, parametric
instability can fix the amplitude of the warp.

</DOC>
<DOC>
<DOCNO> 40601 </DOCNO>
Search for R-parity Violating Decays of Supersymmetric Particles at LEP


  Searches for pair-produced charginos, neutralinos and scalar fermions
decaying via R-parity violating / /\' and /\'' couplings with the OPAL detector
at LEP are presented at sqrt(s)=189 GeV. Partial updates using data up to the
highest energies of LEP, sqrt(s)=209 GeV, are also given.

</DOC>
<DOC>
<DOCNO> 122405 </DOCNO>
OPTICON and the Virtual Observatory


  The challenges of multi-wavelength astrophysics require new outlooks from
those appropriate to traditional astronomy. The next generation of research
scientists must be trained to exploit the potentiality now being provided for
the first time. Just as importantly, the full range of available information
must be indexed and made available, to avoid wasteful repeat observations, or
incomplete analyses. Perhaps the greatest challenge in the immediate future is
to ensure the wealth of multi-wavelength data already available, and being
accumulated, is available for efficient scientific exploitation. The difference
between observations in a depositary and a fully-operational data archive is
the difference between waste and cutting-edge science. The EU Optical Infrared
Coordination Network for Astronomy (OPTICON) provides a forum to coordinate and
develop the many national and international efforts and desires leading towards
an operational virtial observatory.

</DOC>
<DOC>
<DOCNO> 116984 </DOCNO>
Ground Motion Model of the SLAC Site


  We present a ground motion model for the SLAC site. This model is based on
recent ground motion studies performed at SLAC as well as on historical data.
The model includes wave-like, diffusive and systematic types of motion. An
attempt is made to relate measurable secondary properties of the ground motion
with more basic characteristics such as the layered geological structure of the
surrounding earth, depth of the tunnel, etc. This model is an essential step in
evaluating sites for a future linear collider.

</DOC>
<DOC>
<DOCNO> 118406 </DOCNO>
J-Band Infrared Spectroscopy of a Sample of Brown Dwarfs Using Nirspec


  Near-infrared spectroscopic observations of a sample of very cool, low-mass
objects are presented with higher spectral resolution than in any previous
studies. Six of the objects are L-dwarfs, ranging in spectral class from L2 to
L8/9, and the seventh is a methane or T-dwarf. These new observations were
obtained during commissioning of NIRSPEC, the first high-resolution
near-infrared cryogenic spectrograph for the Keck II 10-meter telescope on
Mauna Kea, Hawaii. Spectra with a resolving power of R=2500 from 1.135 to 1.360
microns (approximately J-band) are presented for each source. At this
resolution, a rich spectral structure is revealed, much of which is due to
blending of unresolved molecular transitions. Strong lines due to neutral
potassium (K I), and bands due to iron hydride (FeH) and steam (H2O) change
significantly throughout the L sequence. Iron hydride disappears between L5 and
L8, the steam bands deepen and the K I lines gradually become weaker but wider
due to pressure broadening. An unidentified feature occurs at 1.22 microns
which has a temperature dependence like FeH but has no counterpart in the
available FeH opacity data. Because these objects are 3-6 magnitudes brighter
in the near-infrared compared to the I-band, spectral classification is
efficient. One of the objects studied (2MASSW J1523+3014) is the coolest
L-dwarf discovered so far by the 2-Micron All-Sky Survey (2MASS), but its
spectrum is still significantly different from the methane-dominated objects
such as Gl229B or SDSS 1624+0029.

</DOC>
<DOC>
<DOCNO> 71984 </DOCNO>
Wall Velocity in the MSSM


  We compute the wall velocity in the MSSM with W, tops and stops contributing
to the friction. In a wide range of parameters including those which fulfil the
requirements of baryogenesis we find a wall velocity of order v_w=O(0.01) much
below the SM value.

</DOC>
<DOC>
<DOCNO> 12901 </DOCNO>
Spectral Properties of the k-Body Embedded Gaussian Ensembles of Random


  We consider $m$ spinless Fermions in $l > m$ degenerate single-particle
levels interacting via a $k$-body random interaction with Gaussian probability
distribution and $k <= m$ in the limit $l$ to infinity (the embedded $k$-body
random ensembles). We address the cases of orthogonal and unitary symmetry. We
derive a novel eigenvalue expansion for the second moment of the Hilbert-space
matrix elements of these ensembles. Using properties of the expansion and the
supersymmetry technique, we show that for $2k > m$, the average spectrum has
the shape of a semicircle, and the spectral fluctuations are of Wigner-Dyson
type. Using a generalization of the binary correlation approximation, we show
that for $k << m << l$, the spectral fluctuations are Poissonian. This is
consistent with the case $k = 1$ which can be solved explicitly. We construct
limiting ensembles which are either fully integrable or fully chaotic and show
that the $k$-body random ensembles lie between these two extremes. Combining
all these results we find that the spectral correlations for the embedded
ensembles gradually change from Wigner-Dyson for $2k > m$ to Poissonian for $k
<< m << l$.

</DOC>
<DOC>
<DOCNO> 152108 </DOCNO>
Density of States and Tachyons in Open and Closed String Theory


  In this note we reexamine the possibility of constructing stable
non-supersymmetric theories that exhibit an exponential density of states. For
weakly coupled closed strings there is a general theorem, according to which
stable theories with an exponential density of states must exhibit an almost
exact cancellation of spacetime bosons and fermions (not necessarily level by
level). We extend this result to open strings by showing that if the above
cancellation between bosons and fermions does not occur, the open strings do
not decouple from a closed string tachyon even in the NCOS scaling limit. We
conclude with a brief comment on the proposed generalization of the AdS/CFT
correspondence to non-supersymmetric theories.

</DOC>
<DOC>
<DOCNO> 120348 </DOCNO>
The Stability of Radiatively Cooled Jets in Three Dimensions


  The effect of optically thin radiative cooling on the Kelvin-Helmholtz
instability of three dimensional jets is investigated via linear stability
theory and nonlinear hydrodynamical simulation. Two different cooling functions
are considered: radiative cooling is found to have a significant effect on the
stability of the jet in each case. The wavelengths and growth rates of unstable
modes in the numerical simulations are found to be in good agreement with
theoretical predictions. Disruption of the jet is found to be sensitive to the
precessional frequency at the origin with lower frequencies leading to more
rapid disruption. Strong nonlinear effects are observed as the result of the
large number of normal modes in three dimensions which provide rich mode-mode
interactions. These mode-mode interactions provide new mechanisms for the
formation of knots in the flows. Significant structural features found in the
numerical simulations appear similar to structures observed on protostellar
jets.

</DOC>
<DOC>
<DOCNO> 67928 </DOCNO>
CP Violation Beyond the Standard Model in Hadronic B Decays


  In this talk I discuss three different methods, using B_d to J/psi K_S, J/psi
K_s pi^o, B_d to K^- pi^+, pi^+ pi^- and B_u to K^- pi^0, bar K^0 pi^- pi^-
pi^0, to extract hadronic model independent information about new physics.

</DOC>
<DOC>
<DOCNO> 40389 </DOCNO>
Experimental Probes of the Randall-Sundrum Infinite Extra Dimension


  The phenomenological possibilities of the Randall-Sundrum non-compact extra
dimension scenario with the AdS horizon increased to approximately a millimeter
length, corresponding to an effective brane tension of TeV^4, are investigated.
The corrections to the Newtonian potential are found to be the only
observationally accessible probe of this scenario, as previously suggested in
the literature. In particular, the presence of the continuum of KK modes does
not lead to any observable collider signatures. The extent to which
experimental tests of Newtonian gravity can distinguish this scenario from the
scenario of Arkani-Hamed, Dimopoulos, and Dvali with one and two millimeter
size extra dimensions is explicitly demonstrated.

</DOC>
<DOC>
<DOCNO> 71120 </DOCNO>
A generalized Bell-Inequality and Decoherence for the


  First a generalized Bell-inequality for different times and for different
quasi-spin states is developed. We focus on special quasi-spin eigenstates and
times. The inequality based on a local realistic theory is violated by the
CP-violating parameter, if the quantum theory is used to recalculate the
probabilities. Next the quantum mechanical probabilities are modified by the
decoherence approach which enables the initial state to factorize
spontaneously. In this way we get a lower limit for the decoherence parameter
\zeta, which measures the degree of decoherence. This result is compared with
the experimental value of the decoherence parameter \zeta deduced from the data
of the CPLEAR-experiment.

</DOC>
<DOC>
<DOCNO> 68085 </DOCNO>
A new determination of the Pomeron intercept in hard processes


  A method allowing for a direct comparison of data with theoretical
predictions is proposed for forward jet production at HERA. It avoids the
reconstruction of multi-parton contributions by expressing the experimental
data directly as correction factors on the QCD forward jet cross-section. An
application to the determination of the effective Pomeron intercept in the
BFKL-LO parametrization from dsigma/dx data at HERA leads to a good fit with a
significantly higher effective intercept, alpha_P = 1.43 \pm 0.025(stat.) \pm
>.025(syst.), than for proton (total and diffractive) structure functions. It
is however less than the value of the Pomeron intercept using dijets with large
rapidity intervals obtained at Tevatron. We also evaluate the rapidity veto
contribution to the higher order BFKL corrections. The method can be extended
to other theoretical inputs.

</DOC>
<DOC>
<DOCNO> 117202 </DOCNO>
A quasi classical approach to fully differential ionization cross


  A classical approximation to time dependent quantum mechanical scattering in
the M\o{}ller formalism is presented. Numerically, our approach is similar to a
standard Classical-Trajectory-Monte-Carlo calculation. Conceptually, however,
our formulation allows one to release the restriction to stationary initial
distributions. This is achieved by a classical forward-backward propagation
technique. As a first application and for comparison with experiment we present
fully differential cross sections for electron impact ionization of atomic
hydrogen in the Erhardt geometry.

</DOC>
<DOC>
<DOCNO> 11049 </DOCNO>
Superconducting joining of melt-textured Y-Ba-Cu-O bulk material


  The Tm-Ba-Cu-O solder can be successfully used to produce a superconductive
joint between MT-YBCO parts. The peculiarities of solidification, phase
formation, structure transformations and electromagnetic properties of MT-YBCO
soldered with TmBa2Cu3O7-d are discussed.

</DOC>
<DOC>
<DOCNO> 152203 </DOCNO>
Compactifying M-Theory to Four Dimensions


  We consider compactifications of ${\cal M}$-theory to four-dimensional
Minkowski space on seven-dimensional non-compact manifolds. These
compactifications include a warp factor which is non-constant due to the
presence of sources coming from fivebranes wrapping two-dimensional
submanifolds of the internal seven-dimensional space. We derive the expression
for the field strengths and consider an explicit example of this general class
of solutions.

</DOC>
<DOC>
<DOCNO> 120621 </DOCNO>
The Fundamental Plane of field early-type galaxies at intermediate


  We present preliminary results on the evolution of the stellar populations of
field early-type galaxies (E/S0) from z=0.4 to z=0. The diagnostic tool used in
this study is the Fundamental Plane (FP), a tight empirical correlation between
their central velocity dispersion (sigma), effective radius (Re), and effective
surface brightness (SBe), which is observed to hold in the local Universe.
Using HST-WFPC2 archive images and spectra obtained at the ESO-3.6m telescope
we measured the FP parameters for a sample of ~30 field E/S0s at z=0.2-0.4.
Remarkably, field E/S0s at intermediate redshift also define a tight FP, with
scatter unchanged with respect to that of local samples. The intermediate
redshift FP is offset from the local one, in the sense that, for given RE and
sigma, galaxies are brighter at z=0.4 than at z=0. The implication of the
offset of the FP in terms of passive evolution of the stellar population
depends on its star formation history. In a single burst scenario, the stellar
populations of field E/S0s were formed at z=0.8-1.6 (Omega=0.3;
Omega_{Lambda}=0.7; H_0=50 km/s/Mpc). Alternatively, the bulk of stars (90% in
mass) can be formed at high redshift (z~3), and the rest in a secondary burst
occurred more recently (z~0.5-0.8).

</DOC>
<DOC>
<DOCNO> 8547 </DOCNO>
Does hardcore interaction change absorbing type critical phenomena?


  It has been generally believed that hardcore interaction is irrelevant to
absorbing type critical phenomena because the particle density is so low near
an absorbing phase transition. We study the effect of hardcore interaction on
the N species branching annihilating random walks with two offspring and report
that hardcore interaction drastically changes the absorbing type critical
phenomena in a nontrivial way. Through Langevin equation type approach, we
predict analytically the values of the scaling exponents, $\nu_{\perp} = 2, z =
2, \alpha = 1/2, \beta = 2$ in one dimension for all N > 1. Direct numerical
simulations confirm our prediction. When the diffusion coefficients for
different species are not identical, $\nu_{\perp}$ and $\beta$ vary
continuously with the ratios between the coefficients.

</DOC>
<DOC>
<DOCNO> 120572 </DOCNO>
The very red afterglow of GRB 000418 - further evidence for dust


  We report near-infrared and optical follow-up observations of the afterglow
of the Gamma-Ray Burst 000418 starting 2.5 days after the occurrence of the
burst and extending over nearly seven weeks. GRB 000418 represents the second
case for which the afterglow was initially identified by observations in the
near-infrared. During the first 10 days its R-band afterglow was well
characterized by a single power-law decay with a slope of 0.86. However, at
later times the temporal evolution of the afterglow flattens with respect to a
simple power-law decay. Attributing this to an underlying host galaxy we find
its magnitude to be R=23.9 and an intrinsic afterglow decay slope of 1.22. The
afterglow was very red with R-K=4 mag. The observations can be explained by an
adiabatic, spherical fireball solution and a heavy reddening due to dust
extinction in the host galaxy. This supports the picture that (long) bursts are
associated with events in star-forming regions.

</DOC>
<DOC>
<DOCNO> 100045 </DOCNO>
Krichever correspondence for algebraic varieties


  In 70's there was discovered a construction how to attach to some
algebraic-geometric data an infinite-dimensional subspace in the space k((z))
of the Laurent power series. Now this construction is called the Krichever map.
In e-print math.AG/9911097 A.N. Parshin suggested a generalization of the
Krichever map for the case of algebraic surfaces from the point of view of
2-dimensional local fields.
  In this work we suggest a generalization of the Krichever map to the case of
algebraic varieties of arbitrary dimension from the point of view of
multidimensional local fields. For surfaces our construction coincides with the
Parshin construction.
  Besides, we obtain new explicit acyclic resolutions of quasicoherent sheaves
connected with multidimensional local fields.

</DOC>
<DOC>
<DOCNO> 101308 </DOCNO>
Self-Similar Measures for Quasicrystals


  We study self-similar measures of Hutchinson type, defined by compact
families of contractions, both in a single and multi-component setting. The
results are applied in the context of general model sets to infer, via a
generalized version of Weyl's Theorem on uniform distribution, the existence of
invariant measures for families of self-similarities of regular model sets.

</DOC>
<DOC>
<DOCNO> 84147 </DOCNO>
The use of new coordinates for the template space in hierarchical search


  We discuss a method to analyze data from interferometric gravitational wave
detectors focusing on the technique of hierarchical search to detect
gravitational waves from inspiraling binaries. For this purpose, we propose new
coordinates to parameterize the template space. Using our new coordinates, we
develop several new techniques for two step search, which would reduce the
computation cost by large amount. These techniques become more important when
we need to implement a $\chi^2$-test as a detection criterion.

</DOC>
<DOC>
<DOCNO> 68169 </DOCNO>
The three-leptons signature from resonant sneutrino production at the


  The resonant production of sneutrinos at the LHC via the R-parity violating
couplings $\l '_{ijk} L_i Q_j D^c_k$ is studied through its three-leptons
signature. A detailed particle level study of signal and background is
performed using a fast simulation of the ATLAS detector. Through the full
reconstruction of the cascade decay, a model-independent and precise
measurement of the masses of the involved sparticles can be performed. Besides,
this signature can be detected in a large part of the SUSY parameter space and
for wide ranges of values of several $\l '_{ijk}$ coupling constants.

</DOC>
<DOC>
<DOCNO> 150433 </DOCNO>
New families of flows between two-dimensional conformal field theories


  We present evidence for the existence of infinitely-many new families of
renormalisation group flows between the nonunitary minimal models of conformal
field theory. These are associated with perturbations by the $\phi_{21}$ and
$\phi_{15}$ operators, and generalise a family of flows discovered by Martins.
In all of the new flows, the finite-volume effective central charge is a
non-monotonic function of the system size. The evolution of this effective
central charge is studied by means of a nonlinear integral equation, a massless
variant of an equation recently found to describe certain massive perturbations
of these same models. We also observe that a similar non-monotonicity arises in
the more familiar $\phi_{13}$ perturbations, when the flows induced are between
nonunitary minimal models.

</DOC>
<DOC>
<DOCNO> 40634 </DOCNO>
Optimization of drift gases for accuracy in pressurized drift tubes


  Modern detectors such as ATLAS use pressurized drift tubes to minimize
diffusion and achieve high coordinate accuracy. However, the coordinate
accuracy depends on the exact knowledge of converting measured times into
coordinates. Linear space-time relationships are best for reconstruction, but
difficult to achieve in the $E \propto \frac{1}{r}$ field. Previous mixtures,
which contained methane or other organic quenchers, are disfavored because of
ageing problems. From our studies of nitrogen and carbon dioxide, two mixtures
with only small deviations from linearity were determined and measured. Scaling
laws for different pressures and magnetic fields are also given.

</DOC>
<DOC>
<DOCNO> 119005 </DOCNO>
Rotational Evolution During Type I X-Ray Bursts


  The rotation rates of six weakly-magnetic neutron stars accreting in low-mass
X-ray binaries have most likely been measured by Type I X-ray burst
observations with RXTE. The nearly coherent oscillations detected during the
few seconds of thermonuclear burning are most simply understood as rotational
modulation of brightness asymmetries on the neutron star surface. We show that,
as suggested by Strohmayer and colleagues, the frequency changes of 1-2 Hz
observed during bursts are consistent with angular momentum conservation as the
burning shell hydrostatically expands and contracts. We calculate how vertical
heat propagation through the radiative outer layers of the atmosphere and
convection affect the coherence of the oscillation. We show that the evolution
of the rotational profile depends strongly on whether the burning layers are
composed of pure helium or mixed hydrogen/helium. Our results help explain the
absence (presence) of oscillations from hydrogen-burning (helium-rich) bursts
that was found by Muno and collaborators.
  We investigate angular momentum transport within the burning layers and the
recoupling of the burning layers with the star. We show that the
Kelvin-Helmholtz instability is quenched by the strong stratification, and that
mixing between the burning fuel and underlying ashes by the baroclinic
instability does not occur. However, the baroclinic instability may have time
to operate within the differentially rotating burning layer, potentially
bringing it into rigid rotation.

</DOC>
<DOC>
<DOCNO> 70343 </DOCNO>
Flavor Asymmetry of the Nucleon Sea


  Recent deep inelastic scattering and Drell-Yan experiments have revealed a
surprisingly large asymmetry between the up and down sea quark distributions in
the nucleon. The current status of the flavor asymmetry of the nucleon sea is
reviewed. Implications of various theoretical models and possible future
measurements are also discussed.

</DOC>
<DOC>
<DOCNO> 152476 </DOCNO>
Dynamics of Effective Gluons


  Renormalized Hamiltonians for gluons are constructed using a perturbative
boost-invariant renormalization group procedure for effective particles in
light-front QCD, including terms up to third order. The effective gluons and
their Hamiltonians depend on the renormalization group parameter lambda, which
defines the width of momentum space form factors that appear in the
renormalized Hamiltonian vertices. Third-order corrections to the three-gluon
vertex exhibit asymptotic freedom, but the rate of change of the vertex with
lambda depends in a finite way on regularization of small-x singularities. This
dependence is shown in some examples, and a class of regularizations with two
distinct scales in x is found to lead to the Hamiltonian running coupling
constant whose dependence on lambda matches the known perturbative result from
Lagrangian calculus for the dependence of gluon three-point Green's function on
the running momentum scale at large scales. In the Fock space basis of
effective gluons with small lambda, the vertex form factors suppress
interactions with large kinetic energy changes and thus remove direct couplings
of low energy constituents to high energy components in the effective bound
state dynamics. This structure is reminiscent of parton and constituent models
of hadrons.

</DOC>
<DOC>
<DOCNO> 170213 </DOCNO>
A Rosetta Stone for Quantum Mechanics with an Introduction to Quantum


  The purpose of these lecture notes is to provide readers, who have some
mathematical background but little or no exposure to quantum mechanics and
quantum computation, with enough material to begin reading the research
literature in quantum computation and quantum information theory. This paper is
a written version of the first of eight one hour lectures given in the American
Mathematical Society (AMS) Short Course on Quantum Computation held in
conjunction with the Annual Meeting of the AMS in Washington, DC, USA in
January 2000, and will appear in the AMS PSAPM volume entitled "Quantum
Computation."
  Part 1 of the paper is an introduction the to the concept of the qubit.
  Part 2 gives an introduction to quantum mechanics covering such topics as
Dirac notation, quantum measurement, Heisenberg uncertainty, Schrodinger's
equation, density operators, partial trace, multipartite quantum systems, the
Heisenberg versus the Schrodinger picture, quantum entanglement, EPR paradox,
quantum entropy.
  Part 3 gives a brief introduction to quantum computation, covering such
topics as elementary quantum computing devices, wiring diagrams, the no-cloning
theorem, quantum teleportation, Shor's algorithm, Grover's algorithm.
  Many examples are given. A table of contents as well as an index are provided
for readers who wish to "pick and choose." Since this paper is intended for a
diverse audience, it is written in an informal style at varying levels of
difficulty and sophistication from the very elementary to the more advanced.

</DOC>
<DOC>
<DOCNO> 170557 </DOCNO>
Deduction of Planck's Formula from Multiphoton States


  We obtain the black body radiation formula of Planck by considering
independent contributions of multiphoton states

</DOC>
<DOC>
<DOCNO> 122314 </DOCNO>
Seeing Galaxies Through Thick & Thin. III. HST Imaging of the Dust in


  We present analysis of WFPC2 imaging of two spiral galaxies partially backlit
by E/S0 systems in the pairs AM1316-241 and AM0500-620, and the spiral
foreground system in NGC 1275. Images in B and I are used to determine the
reddening curve of in these systems. The spiral component of AM1316-241 shows
dust strongly concentrated in discrete arms, with a reddening law very close to
the Milky Way mean. The dust distribution is scale-free between about 100 pc
and the arm scale. The spiral in AM0500-620 shows dust concentrated in arms and
interarm spurs, with measurable interarm extinction as well. Although its dust
properties are less well-determined, we find evidence for a steeper extinction
law here. The shape of the reddening law suggests that, at least in AM1316-241,
we have resolved most of the dust structure. In AM0500-620, the slope of the
fractal perimeter-scale relation steepens systematically from low to high
extinction. In AM1316-241, we cannot determine a unique fractal dimension from
the defining area-perimeter relation, so the projected dust distribution is
best defined as fractal-like. In neither galaxy do we see regions even on
single-pixel scales in spiral arms with AB > 2.5. The measurements in NGC 1275
are compromised by our lack of independent knowledge of the foreground system's
light distribution, but masked sampling of the absorption suggests an effective
reddening curve much flatter than the Milky Way mean (perhaps indicating that
the foreground system has been affected by immersion in the hot intracluster
gas).

</DOC>
<DOC>
<DOCNO> 8408 </DOCNO>
Local magnetic structures induced by inhomogeneities of the lattice in


  We study effect of inhomogeneities of the lattice in the S=1/2
bond-alternating chain by using a quantum Monte Carlo method and an exact
diagonalization method. We adopt a defect in the alternating order as the
inhomogeneity and we call it `bond impurity'. Local magnetic
structures induced by the bond impurities are investigated both in the ground
state and at very low temperatures. The local magnetic structure can be looked
on as an effective S=1/2 spin and the weakness of the interaction between the
local structures causes the quasi-degenerate states in the low energy. We also
investigate the force acting between bond impurities and find that the force is
generally attractive. We also study the dynamical property of the local
magnetic structure. While the local magnetic structure behaves as an isolated
S=1/2 spin in the response to a time-dependent uniform field, it is found to
be robust against the effect of a random noise applied at each site
individually in the sweeping filed.

</DOC>
<DOC>
<DOCNO> 117002 </DOCNO>
Local and Fundamental Mode Coupler Damping of the Transverse Wakefield


  In damping the wakefield generated by an electron beam traversing several
thousand X-band linacs in the NLC we utilise a Gaussian frequency distribution
of dipole modes to force the modes to deconstructively interfere, supplemented
with moderate damping achieved by coupling these modes to four attached
manifolds. Most of these modes are adequately damped by the manifolds. However,
the modes towards the high frequency end of the lower dipole band are not
adequately damped because the last few cells are, due to mechanical fabrication
requirements, not coupled to the manifolds. To mitigate this problem in the
present RDDS1 design, the output coupler for the accelerating mode has been
designed so as to also couple out those dipole modes which reach the output
coupler cell. In order to couple out both dipole mode polarizations, the output
coupler has four ports. We also report on the results of a study of the
benefits which can be achieved by supplementing manifold damping with local
damping for a limited number of cells at the downstream end of the structure.

</DOC>
<DOC>
<DOCNO> 118011 </DOCNO>
What Damped Ly-alpha Systems Tell Us About the Radial Distribution of


  We investigate the properties of damped Lyman-alpha systems (DLAS) in
semi-analytic models, focusing on whether the models can reproduce the
kinematic properties of low-ionization metal lines described by Prochaska &
Wolfe (1997b, 1998). We explore a variety of approaches for modelling the
radial distribution of the cold neutral gas associated with the galaxies in our
models, and find that our results are very sensitive to this ingredient. If we
use an approach based on Fall & Efstathiou (1980), in which the sizes of the
discs are determined by conservation of angular momentum, we find that the
majority of the DLAS correspond to a single galactic disc. These models
generically fail to reproduce the observed distribution of velocity widths. In
alternative models in which the gas discs are considerably more extended, a
significant fraction of DLAS arise from lines of sight intersecting multiple
gas discs in a common halo. These models produce kinematics that fit the
observational data, and also seem to agree well with the results of recent
hydrodynamical simulations. Thus we conclude that Cold Dark Matter based models
of galaxy formation can be reconciled with the kinematic data, but only at the
expense of the standard assumption that DLAS are produced by rotationally
supported gas discs whose sizes are determined by conservation of angular
momentum. We suggest that the distribution of cold gas at high redshift may be
dominated by another process, such as tidal streaming due to mergers.

</DOC>
<DOC>
<DOCNO> 40105 </DOCNO>
Charged particle multiplicity near mid-rapidity in central Au+Au


  We present the first measurement of pseudorapidity densities of primary
charged particles near mid-rapidity in Au+Au collisions at $\sqrt{s} =$ 56 and
130 AGeV. For the most central collisions, we find the charged particle
pseudorapidity density to be $dN/d\eta |_{|\eta|<1} = 408 \pm 12 {(stat)} \pm
30 {(syst)}$ at 56 AGeV and $555 \pm 12 {(stat)} \pm 35 {(syst)}$ at 130 AGeV,
values that are higher than any previously observed in nuclear collisions.
Compared to proton-antiproton collisions, our data show an increase in the
pseudorapidity density per participant by more than 40% at the higher energy.

</DOC>
<DOC>
<DOCNO> 8328 </DOCNO>
Localization-delocalization transition of disordered d-wave


  A lattice model for disordered d-wave superconductors in class CI is
reconsidered. Near the band-center, the lattice model can be described by Dirac
fermions with several species, each of which yields WZW term for an effective
action of the Goldstone mode. The WZW terms cancel out each other because of
the four-fold symmetry of the model, which suggests that the quasiparticle
states are localized. If the lattice model has, however, symmetry breaking
terms which generate mass for any species of the Dirac fermions, remaining WZW
term which avoids the cancellation can derive the system to a delocalized
strong-coupling fixed point.

</DOC>
<DOC>
<DOCNO> 11465 </DOCNO>
Diagram technique for perturbation theory calculations of the effective


  The perturbation theory for calculation of the effective conductivity of the
plane consisting of pieces of different conductivities is constructed and the
convenient diagram technique for this perturbation theory is elaborated. It is
shown that for the chessboard perturbative calculations give results which are
in agreement with the well-known formula $\sigma_{eff} =
\sqrt{\sigma_1\sigma_2}$. The components of the tensor of effective
conductivity for the anisotropic three-color chessboard are calculated. It is
shown that the isotropic (symmetric) part of effective conductivity calculated
up to the sixth order of perturbation theory satisfies the Bruggeman effective
medium equation for symmetric three-color structures with equally partitioned
components. We also consider isotropic three-color chessboard with nonequal
weights of colors. In this case the perturbation theory already in fourth order
contradicts the results following from the Bruggeman equation for nonequal
weights.

</DOC>
<DOC>
<DOCNO> 9358 </DOCNO>
Metallic and nonmetallic double perovskites: A case study of


  We have investigated the structure and electronic properties of ferrimagnetic
double perovskites, A2FeReO6 (A= Ca, Sr, Ba). The A=Ba phase is cubic (Fm3m)
and metallic, while the A=Ca phase is monoclinic (P21/n) and nonmetallic.
  57Fe Mossbauer spectroscopy shows that iron is present mainly in the
high-spin (S=5/2) Fe3+ state in the Ca compound, while it occurs in an
intermediate state between high-spin Fe2+ and Fe3+ in the Ba compound. It is
argued that a direct Re t2g - Re t2g interaction is the main cause for the
metallic character of the Ba compound; the high covalency of Ca-O bonds and the
monoclinic distortion (which lifts the degeneracy of t2g states) seem to
disrupt the Re-Re interaction in the case of the Ca compound, making it
non-metallic for the same electron count.

</DOC>
<DOC>
<DOCNO> 170355 </DOCNO>
Lateral projection as a possible explanation of the nontrivial boundary


  We find the lateral projection of the Casimir force for a configuration of a
sphere above a corrugated plate. This force tends to change the sphere position
in the direction of a nearest corrugation maximum. The probability distribution
describing different positions of a sphere above a corrugated plate is
suggested which is fitted well with experimental data demonstrating the
nontrivial boundary dependence of the Casimir force.

</DOC>
<DOC>
<DOCNO> 101980 </DOCNO>
Two characterizations of the standard unit vector basis of $l_1$


  We show that for a sequence in a Banach space, the property of being stable
under large perturbations characterizes the property of being equivalent to the
unit vector basis of $l_1$. We show that a normalized unconditional basic
sequence in $l_1$ that is semi-normalized in $l_\infty$ is equivalent to the
standard unit vector basis of~$l_1$.

</DOC>
<DOC>
<DOCNO> 121069 </DOCNO>
Photometric deprojection of edge-on galaxies


  Photometric deprojection is used to determine the stellardisk and bulge
parameters for several edgeon galaxies from the FGC catalog. The assumption
that the galaxies of our sample belonging to the fourth (i.e., lowest)
surfacebrightness class in the FGC are edgeon, lowsurfacebrightness (LSB)
galaxies is considered.

</DOC>
<DOC>
<DOCNO> 116774 </DOCNO>
Magnetic Field of Relativistic Nonlinear Plasma Wave


  Longitudinal and transverse behavior of magnetic field of relativistic
nonlinear three-dimensional plasma wave is investigated. It is shown that the
magnetic field of the wave is different from zero and performs higher frequency
oscillations compared to the plasma electron frequency. An increase in the
nonlinearity leads to strengthening of magnetic field. The oscillations of
magnetic field in transverse direction arise, that caused by the phase front
curving of nonlinear plasma wave. The numerical results well conform with
predictions of the analytical consideration of weakly-nonlinear case.

</DOC>
<DOC>
<DOCNO> 178869 </DOCNO>
Toy Model for Pion Production in Nucleon-Nucleon Collisions


  We develop a toy model of pion production in nucleon-nucleon collisions that
reproduces some of the features of the chiral Lagrangian calculations. We
calculate the production amplitude and examine some common approximations.

</DOC>
<DOC>
<DOCNO> 14112 </DOCNO>
Magnetic order and spin-waves in the quasi-1D S=1/2 antiferromagnet


  Elastic and inelastic neutron scattering were used to study the ordered phase
of the quasi-one-dimensional spin-1/2 antiferromagnet ${\rm
BaCu_{2}Si_{2}O_{7}}$. The previously proposed model for the low-temperature
magnetic structure was confirmed. Spin wave dispersion along several
reciprocal-space directions was measured and inter-chain, as well as in-chain
exchange constants were determined. A small gap in the spin wave spectrum was
observed and attributed to magnetic anisotropy effects. The results are
discussed in comparison with existing theories for weakly-coupled quantum spin
chain antiferromagnets.

</DOC>
<DOC>
<DOCNO> 71345 </DOCNO>
The Colored Glass Condensate and Extreme QCD


  The high energy limit of QCD is controlled by the small-$x$ part of a hadron
wavefunction. I argue that this part is universal to all hadrons and is
composed of a new form of matter: a Colored Glass Condensate. This matter is
weakly interacting at very small $x$, but is non-perturbative because of the
highly occupied boson states which compose the condensate. Such a matter might
be studied in high energy lepton-hadron or hadron-hadron interactions.

</DOC>
<DOC>
<DOCNO> 84986 </DOCNO>
WKB Wave Functions with the Induced Gravity Theory


  The Wheeler-DeWitt equation for the induced gravity theory is constructed in
the minisuperspace approximation, and then solved using the WKB method under
three types of boundary condition proposed respectively by Hartle & Hawking
(``no boundary''), Linde and Vilenkin (``tunneling from nothing''). It is found
that no matter how the gravitational and cosmological ``constants'' vary in the
classical models, they will acquire constant values when the universe comes
from quantum creation, and that, in particular, the resulting tunneling wave
function under the Linde or Vilenkin boundary condition reaches its maximum
value if the cosmological constant vanishes.

</DOC>
<DOC>
<DOCNO> 151839 </DOCNO>
Holographic Duals of 4D Field Theories


  We discuss various aspect of the holographic correspondence between 5-d
gravity and 4-d field theory. First of all, we describe deformations of N=4
Super Yang-Mills (SYM) theories in terms of 5-d gauged supergravity. In
particular, we describe N=0 and N=1 deformations of N=4 SYM to confining
theories. Secondly, we describe recent proposals for the holographic dual of
the renormalization group and for 4-d central charges associated to it. We
conclude with a ``holographic'' proof of the Goldstone theorem.

</DOC>
<DOC>
<DOCNO> 8353 </DOCNO>
Multi-scaling properties of truncated Levy flights


  Multi-scaling properties of one-dimensional truncated Levy flights are
studied. Due to the broken self-similarity of the distribution of jumps, they
are expected to possess multi-scaling properties in contrast to the ordinary
Levy flights. We argue this fact based on a smoothly truncated Levy
distribution, and derive the functional form of the scaling exponents.
Specifically, they exhibit bi-fractal behavior, which is the simplest case of
multi-scaling.

</DOC>
<DOC>
<DOCNO> 70776 </DOCNO>
"Self-tuning" and Conformality


  We consider an infinite-volume brane world setup where a codimension one
brane is coupled to bulk gravity plus a scalar field with vanishing potential.
The latter is protected by bulk supersymmetry, which is intact even if brane
supersymmetry is completely broken as the volume of the extra dimension is
infinite. Within this setup we discuss a flat solution with a ``self-tuning''
property, that is, such a solution exists for a continuous range of values for
the brane tension. This infinite-volume solution is free of any singularities,
and has the property that the brane cosmological constant is protected by bulk
supersymmetry. We, however, also point out that consistency of the coupling
between bulk gravity and brane matter generically appears to require that the
brane world-volume theory be conformal.

</DOC>
<DOC>
<DOCNO> 13198 </DOCNO>
Boundary Critical Phenomena in SU(3) "Spin" Chains


  SU(3)-invariant "spin" chains with a single impurity, such as a modified
exchange coupling on one link, are analyzed using boundary conformal field
theory techniques. These chains are equivalent to a special case of the "tJV"
model, i.e. the t-J model with a nearest neighbour repulsion added. In the
continuum limit they are equivalent to two free bosons at a special value of
the compactification radii. The SU(3) symmetry, which is made explicit in this
formulation, provides insight into the exact solution of a non-trivial boundary
critical point found earlier in another formulation of this model as a theory
of quantum Brownian motion.

</DOC>
<DOC>
<DOCNO> 99999 </DOCNO>
Irreducibility and Compositeness in q-Deformed Harmonic Oscillator


  q-Deformed harmonic oscillator algebra for real and root of unity values of
the deformation parameter is discussed by using an extension of the number
concept proposed by Gauss, namely the Q-numbers. A study of the reducibility of
the Fock space representation which explores the properties of the Gauss
polynomials is presented. When the deformation parameter is a root of unity, an
interesting result comes out in the form of a reducibility scheme for the space
representation which is based on the classification of the primitive or
non-primitive character of the deformation parameter. An application is carried
out for a q-deformed harmonic oscillator Hamiltonian, to which the reducibility
scheme is explicitly applied. For finite-dimensional spaces associated to
non-primitive roots of unity the compositeness of the k-fermions/quons is
discussed.

</DOC>
